// Copyright 2016 The BoringSSL Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package runner

import (
	"bytes"
	"crypto"
	"crypto/ecdsa"
	"crypto/ed25519"
	"crypto/elliptic"
	"crypto/rand"
	"crypto/rsa"
	"crypto/x509"
	"crypto/x509/pkix"
	_ "embed"
	"encoding/base64"
	"encoding/binary"
	"encoding/hex"
	"encoding/json"
	"encoding/pem"
	"errors"
	"flag"
	"fmt"
	"io"
	"math/big"
	"net"
	"os"
	"os/exec"
	"path/filepath"
	"runtime"
	"slices"
	"strconv"
	"strings"
	"sync"
	"syscall"
	"time"

	"boringssl.googlesource.com/boringssl.git/ssl/test/runner/hpke"
	"boringssl.googlesource.com/boringssl.git/util/testresult"
	"golang.org/x/crypto/cryptobyte"
)

var (
	useValgrind        = flag.Bool("valgrind", false, "If true, run code under valgrind")
	useGDB             = flag.Bool("gdb", false, "If true, run BoringSSL code under gdb")
	useLLDB            = flag.Bool("lldb", false, "If true, run BoringSSL code under lldb")
	useRR              = flag.Bool("rr-record", false, "If true, run BoringSSL code under `rr record`.")
	waitForDebugger    = flag.Bool("wait-for-debugger", false, "If true, jobs will run one at a time and pause for a debugger to attach")
	flagDebug          = flag.Bool("debug", false, "Hexdump the contents of the connection")
	mallocTest         = flag.Int64("malloc-test", -1, "If non-negative, run each test with each malloc in turn failing from the given number onwards.")
	mallocTestDebug    = flag.Bool("malloc-test-debug", false, "If true, ask bssl_shim to abort rather than fail a malloc. This can be used with a specific value for --malloc-test to identity the malloc failing that is causing problems.")
	jsonOutput         = flag.String("json-output", "", "The file to output JSON results to.")
	pipe               = flag.Bool("pipe", false, "If true, print status output suitable for piping into another program.")
	testToRun          = flag.String("test", "", "Semicolon-separated patterns of tests to run, or empty to run all tests")
	skipTest           = flag.String("skip", "", "Semicolon-separated patterns of tests to skip")
	allowHintMismatch  = flag.String("allow-hint-mismatch", "", "Semicolon-separated patterns of tests where hints may mismatch")
	numWorkersFlag     = flag.Int("num-workers", runtime.NumCPU(), "The number of workers to run in parallel.")
	shimPath           = flag.String("shim-path", "../../../build/ssl/test/bssl_shim", "The location of the shim binary.")
	shimExtraFlags     = flag.String("shim-extra-flags", "", "Semicolon-separated extra flags to pass to the shim binary on each invocation.")
	handshakerPath     = flag.String("handshaker-path", "../../../build/ssl/test/handshaker", "The location of the handshaker binary.")
	fuzzer             = flag.Bool("fuzzer", false, "If true, tests against a BoringSSL built in fuzzer mode.")
	transcriptDir      = flag.String("transcript-dir", "", "The directory in which to write transcripts.")
	idleTimeout        = flag.Duration("idle-timeout", 15*time.Second, "The number of seconds to wait for a read or write to bssl_shim.")
	deterministic      = flag.Bool("deterministic", false, "If true, uses a deterministic PRNG in the runner.")
	allowUnimplemented = flag.Bool("allow-unimplemented", false, "If true, report pass even if some tests are unimplemented.")
	looseErrors        = flag.Bool("loose-errors", false, "If true, allow shims to report an untranslated error code.")
	shimConfigFile     = flag.String("shim-config", "", "A config file to use to configure the tests for this shim.")
	includeDisabled    = flag.Bool("include-disabled", false, "If true, also runs disabled tests.")
	repeatUntilFailure = flag.Bool("repeat-until-failure", false, "If true, the first selected test will be run repeatedly until failure.")
)

// ShimConfigurations is used with the “json” package and represents a shim
// config file.
type ShimConfiguration struct {
	// DisabledTests maps from a glob-based pattern to a freeform string.
	// The glob pattern is used to exclude tests from being run and the
	// freeform string is unparsed but expected to explain why the test is
	// disabled.
	DisabledTests map[string]string

	// ErrorMap maps from expected error strings to the correct error
	// string for the shim in question. For example, it might map
	// “:NO_SHARED_CIPHER:” (a BoringSSL error string) to something
	// like “SSL_ERROR_NO_CYPHER_OVERLAP”.
	ErrorMap map[string]string

	// HalfRTTTickets is the number of half-RTT tickets the client should
	// expect before half-RTT data when testing 0-RTT.
	HalfRTTTickets int

	// AllCurves is the list of all curve code points supported by the shim.
	// This is currently used to control tests that enable all curves but may
	// automatically disable tests in the future.
	AllCurves []int

	// MaxACKBuffer is the maximum number of received records the shim is
	// expected to retain when ACKing.
	MaxACKBuffer int
}

// Setup shimConfig defaults aligning with BoringSSL.
var shimConfig ShimConfiguration = ShimConfiguration{
	HalfRTTTickets: 2,
	MaxACKBuffer:   32,
}

//go:embed rsa_2048_key.pem
var rsa2048KeyPEM []byte

//go:embed rsa_1024_key.pem
var rsa1024KeyPEM []byte

//go:embed ecdsa_p224_key.pem
var ecdsaP224KeyPEM []byte

//go:embed ecdsa_p256_key.pem
var ecdsaP256KeyPEM []byte

//go:embed ecdsa_p384_key.pem
var ecdsaP384KeyPEM []byte

//go:embed ecdsa_p521_key.pem
var ecdsaP521KeyPEM []byte

//go:embed ed25519_key.pem
var ed25519KeyPEM []byte

//go:embed channel_id_key.pem
var channelIDKeyPEM []byte

var (
	rsa1024Key rsa.PrivateKey
	rsa2048Key rsa.PrivateKey

	ecdsaP224Key ecdsa.PrivateKey
	ecdsaP256Key ecdsa.PrivateKey
	ecdsaP384Key ecdsa.PrivateKey
	ecdsaP521Key ecdsa.PrivateKey

	ed25519Key ed25519.PrivateKey

	channelIDKey ecdsa.PrivateKey
)

var channelIDKeyPath string

func initKeys() {
	// Since key generation is not particularly cheap (especially RSA), and the
	// runner is intended to run on systems which may be resouece constrained,
	// we load keys from disk instead of dynamically generating them. We treat
	// key files the same as dynamically generated certificates, writing them
	// out to temporary files before passing them to the shim.

	for _, k := range []struct {
		pemBytes []byte
		key      *rsa.PrivateKey
	}{
		{rsa1024KeyPEM, &rsa1024Key},
		{rsa2048KeyPEM, &rsa2048Key},
	} {
		key, err := loadPEMKey(k.pemBytes)
		if err != nil {
			panic(fmt.Sprintf("failed to load RSA test key: %s", err))
		}
		*k.key = *(key.(*rsa.PrivateKey))
	}

	for _, k := range []struct {
		pemBytes []byte
		key      *ecdsa.PrivateKey
	}{
		{ecdsaP224KeyPEM, &ecdsaP224Key},
		{ecdsaP256KeyPEM, &ecdsaP256Key},
		{ecdsaP384KeyPEM, &ecdsaP384Key},
		{ecdsaP521KeyPEM, &ecdsaP521Key},
		{channelIDKeyPEM, &channelIDKey},
	} {
		key, err := loadPEMKey(k.pemBytes)
		if err != nil {
			panic(fmt.Sprintf("failed to load ECDSA test key: %s", err))
		}
		*k.key = *(key.(*ecdsa.PrivateKey))
	}

	k, err := loadPEMKey(ed25519KeyPEM)
	if err != nil {
		panic(fmt.Sprintf("failed to load Ed25519 test key: %s", err))
	}
	ed25519Key = k.(ed25519.PrivateKey)

	channelIDKeyPath = writeTempKeyFile(&channelIDKey)
}

var channelIDBytes []byte

var (
	testOCSPResponse  = []byte{1, 2, 3, 4}
	testOCSPResponse2 = []byte{5, 6, 7, 8}
	testSCTList       = []byte{0, 6, 0, 4, 5, 6, 7, 8}
	testSCTList2      = []byte{0, 6, 0, 4, 1, 2, 3, 4}
)

var (
	testOCSPExtension = append([]byte{byte(extensionStatusRequest) >> 8, byte(extensionStatusRequest), 0, 8, statusTypeOCSP, 0, 0, 4}, testOCSPResponse...)
	testSCTExtension  = append([]byte{byte(extensionSignedCertificateTimestamp) >> 8, byte(extensionSignedCertificateTimestamp), 0, byte(len(testSCTList))}, testSCTList...)
)

var (
	rsaCertificate       Credential
	rsaChainCertificate  Credential
	rsa1024Certificate   Credential
	ecdsaP224Certificate Credential
	ecdsaP256Certificate Credential
	ecdsaP384Certificate Credential
	ecdsaP521Certificate Credential
	ed25519Certificate   Credential
	garbageCertificate   Credential
)

func initCertificates() {
	for _, def := range []struct {
		name string
		key  crypto.Signer
		out  *Credential
	}{
		{"Test RSA-1024 Cert", &rsa1024Key, &rsa1024Certificate},
		{"Test RSA-2048 Cert", &rsa2048Key, &rsaCertificate},
		{"Test ECDSA P-224 Cert", &ecdsaP224Key, &ecdsaP224Certificate},
		{"Test ECDSA P-256 Cert", &ecdsaP256Key, &ecdsaP256Certificate},
		{"Test ECDSA P-384 Cert", &ecdsaP384Key, &ecdsaP384Certificate},
		{"Test ECDSA P-521 Cert", &ecdsaP521Key, &ecdsaP521Certificate},
		{"Test Ed25519 Cert", ed25519Key, &ed25519Certificate},
	} {
		template := *baseCertTemplate
		template.Subject.CommonName = def.name
		*def.out = generateSingleCertChain(&template, def.key)
	}

	channelIDBytes = make([]byte, 64)
	writeIntPadded(channelIDBytes[:32], channelIDKey.X)
	writeIntPadded(channelIDBytes[32:], channelIDKey.Y)

	garbageCertificate.Certificate = [][]byte{[]byte("GARBAGE")}
	garbageCertificate.PrivateKey = rsaCertificate.PrivateKey

	// Build a basic three cert chain for testing chain specific things.
	rootTmpl := *baseCertTemplate
	rootTmpl.Subject.CommonName = "test root"
	rootCert := generateTestCert(&rootTmpl, nil, &rsa2048Key)
	intermediateTmpl := *baseCertTemplate
	intermediateTmpl.Subject.CommonName = "test inter"
	intermediateCert := generateTestCert(&intermediateTmpl, rootCert, &rsa2048Key)
	leafTmpl := *baseCertTemplate
	leafTmpl.IsCA, leafTmpl.BasicConstraintsValid = false, false
	leafCert := generateTestCert(nil, intermediateCert, &rsa2048Key)

	keyPath := writeTempKeyFile(&rsa2048Key)
	rootCertPath, chainPath := writeTempCertFile([]*x509.Certificate{rootCert}), writeTempCertFile([]*x509.Certificate{leafCert, intermediateCert})

	rsaChainCertificate = Credential{
		Certificate:     [][]byte{leafCert.Raw, intermediateCert.Raw},
		RootCertificate: rootCert.Raw,
		PrivateKey:      &rsa2048Key,
		Leaf:            leafCert,
		ChainPath:       chainPath,
		KeyPath:         keyPath,
		RootPath:        rootCertPath,
	}
}

func flagInts(flagName string, vals []int) []string {
	ret := make([]string, 0, 2*len(vals))
	for _, val := range vals {
		ret = append(ret, flagName, strconv.Itoa(val))
	}
	return ret
}

func base64FlagValue(in []byte) string {
	return base64.StdEncoding.EncodeToString(in)
}

func useDebugger() bool {
	return *useGDB || *useLLDB || *useRR || *waitForDebugger
}

// delegatedCredentialConfig specifies the shape of a delegated credential, not
// including the keys themselves.
type delegatedCredentialConfig struct {
	// lifetime is the amount of time, from the notBefore of the parent
	// certificate, that the delegated credential is valid for. If zero, then 24
	// hours is assumed.
	lifetime time.Duration
	// dcAlgo is the signature scheme that should be used with this delegated
	// credential. If zero, ECDSA with P-256 is assumed.
	dcAlgo signatureAlgorithm
	// algo is the signature algorithm that the delegated credential itself is
	// signed with. Cannot be zero.
	algo signatureAlgorithm
}

func loadPEMKey(pemBytes []byte) (crypto.PrivateKey, error) {
	block, _ := pem.Decode(pemBytes)
	if block == nil {
		return nil, fmt.Errorf("no PEM block found")
	}

	if block.Type != "PRIVATE KEY" {
		return nil, fmt.Errorf("unexpected PEM type (expected \"PRIVATE KEY\"): %s", block.Type)
	}

	k, err := x509.ParsePKCS8PrivateKey(block.Bytes)
	if err != nil {
		return nil, fmt.Errorf("failed to parse PKCS#8 key: %s", err)
	}

	return k, nil
}

func createDelegatedCredential(parent *Credential, config delegatedCredentialConfig) *Credential {
	if parent.Type != CredentialTypeX509 {
		panic("delegated credentials must be issued by X.509 credentials")
	}

	dcAlgo := config.dcAlgo
	if dcAlgo == 0 {
		dcAlgo = signatureECDSAWithP256AndSHA256
	}

	var dcPriv crypto.Signer
	switch dcAlgo {
	case signatureRSAPKCS1WithMD5, signatureRSAPKCS1WithSHA1, signatureRSAPKCS1WithSHA256, signatureRSAPKCS1WithSHA384, signatureRSAPKCS1WithSHA512, signatureRSAPSSWithSHA256, signatureRSAPSSWithSHA384, signatureRSAPSSWithSHA512:
		dcPriv = &rsa2048Key

	case signatureECDSAWithSHA1, signatureECDSAWithP256AndSHA256, signatureECDSAWithP384AndSHA384, signatureECDSAWithP521AndSHA512:
		var curve elliptic.Curve
		switch dcAlgo {
		case signatureECDSAWithSHA1, signatureECDSAWithP256AndSHA256:
			curve = elliptic.P256()
		case signatureECDSAWithP384AndSHA384:
			curve = elliptic.P384()
		case signatureECDSAWithP521AndSHA512:
			curve = elliptic.P521()
		default:
			panic("internal error")
		}

		priv, err := ecdsa.GenerateKey(curve, rand.Reader)
		if err != nil {
			panic(err)
		}
		dcPriv = priv

	default:
		panic(fmt.Errorf("unsupported DC signature algorithm: %x", dcAlgo))
	}

	lifetime := config.lifetime
	if lifetime == 0 {
		lifetime = 24 * time.Hour
	}
	lifetimeSecs := int64(lifetime.Seconds())
	if lifetimeSecs < 0 || lifetimeSecs > 1<<32 {
		panic(fmt.Errorf("lifetime %s is too long to be expressed", lifetime))
	}

	// https://www.rfc-editor.org/rfc/rfc9345.html#section-4
	dc := cryptobyte.NewBuilder(nil)
	dc.AddUint32(uint32(lifetimeSecs))
	dc.AddUint16(uint16(dcAlgo))

	pubBytes, err := x509.MarshalPKIXPublicKey(dcPriv.Public())
	if err != nil {
		panic(err)
	}
	addUint24LengthPrefixedBytes(dc, pubBytes)

	var dummyConfig Config
	parentSignature, err := signMessage(false /* server */, VersionTLS13, parent.PrivateKey, &dummyConfig, config.algo, delegatedCredentialSignedMessage(dc.BytesOrPanic(), config.algo, parent.Leaf.Raw))
	if err != nil {
		panic(err)
	}

	dc.AddUint16(uint16(config.algo))
	addUint16LengthPrefixedBytes(dc, parentSignature)

	dcCred := *parent
	dcCred.Type = CredentialTypeDelegated
	dcCred.DelegatedCredential = dc.BytesOrPanic()
	dcCred.PrivateKey = dcPriv
	dcCred.KeyPath = writeTempKeyFile(dcPriv)
	return &dcCred
}

// recordVersionToWire maps a record-layer protocol version to its wire
// representation.
func recordVersionToWire(vers uint16, protocol protocol) uint16 {
	if protocol == dtls {
		switch vers {
		case VersionTLS12:
			return VersionDTLS12
		case VersionTLS10:
			return VersionDTLS10
		}
	} else {
		switch vers {
		case VersionSSL30, VersionTLS10, VersionTLS11, VersionTLS12:
			return vers
		}
	}

	panic("unknown version")
}

// encodeDERValues encodes a series of bytestrings in comma-separated-hex form.
func encodeDERValues(values [][]byte) string {
	var ret string
	for i, v := range values {
		if i > 0 {
			ret += ","
		}
		ret += hex.EncodeToString(v)
	}

	return ret
}

func decodeHexOrPanic(in string) []byte {
	ret, err := hex.DecodeString(in)
	if err != nil {
		panic(err)
	}
	return ret
}

type testType int

const (
	clientTest testType = iota
	serverTest
)

func (t testType) String() string {
	switch t {
	case clientTest:
		return "Client"
	case serverTest:
		return "Server"
	}
	panic(fmt.Sprintf("bad test type %d", t))
}

type protocol int

const (
	tls protocol = iota
	dtls
	quic
)

func (p protocol) String() string {
	switch p {
	case tls:
		return "TLS"
	case dtls:
		return "DTLS"
	case quic:
		return "QUIC"
	}
	return "unknown protocol"
}

const (
	alpn = 1
	npn  = 2
)

// connectionExpectations contains connection-level test expectations to check
// on the runner side.
type connectionExpectations struct {
	// version, if non-zero, specifies the TLS version that must be negotiated.
	version uint16
	// cipher, if non-zero, specifies the TLS cipher suite that should be
	// negotiated.
	cipher uint16
	// channelID controls whether the connection should have negotiated a
	// Channel ID with channelIDKey.
	channelID bool
	// nextProto controls whether the connection should negotiate a next
	// protocol via NPN or ALPN.
	nextProto string
	// noNextProto, if true, means that no next protocol should be negotiated.
	noNextProto bool
	// nextProtoType, if non-zero, is the next protocol negotiation mechanism.
	nextProtoType int
	// srtpProtectionProfile is the DTLS-SRTP profile that should be negotiated.
	// If zero, none should be negotiated.
	srtpProtectionProfile uint16
	// peerSignatureAlgorithm, if not zero, is the signature algorithm that the
	// peer should have used in the handshake.
	peerSignatureAlgorithm signatureAlgorithm
	// curveID, if not zero, is the curve that the handshake should have used.
	curveID CurveID
	// peerCertificate, if not nil, is the credential the peer is expected to
	// send.
	peerCertificate *Credential
	// quicTransportParams contains the QUIC transport parameters that are to be
	// sent by the peer using codepoint 57.
	quicTransportParams []byte
	// quicTransportParamsLegacy contains the QUIC transport parameters that are
	// to be sent by the peer using legacy codepoint 0xffa5.
	quicTransportParamsLegacy []byte
	// peerApplicationSettings are the expected application settings for the
	// connection. If nil, no application settings are expected.
	peerApplicationSettings []byte
	// peerApplicationSettingsOld are the expected application settings for
	// the connection that are to be sent by the peer using old codepoint.
	// If nil, no application settings are expected.
	peerApplicationSettingsOld []byte
	// echAccepted is whether ECH should have been accepted on this connection.
	echAccepted bool
}

type testCase struct {
	testType      testType
	protocol      protocol
	name          string
	config        Config
	shouldFail    bool
	expectedError string
	// expectedLocalError, if not empty, contains a substring that must be
	// found in the local error.
	expectedLocalError string
	// expectations contains test expectations for the initial
	// connection.
	expectations connectionExpectations
	// resumeExpectations, if non-nil, contains test expectations for the
	// resumption connection. If nil, |expectations| is used.
	resumeExpectations *connectionExpectations
	// messageLen is the length, in bytes, of the test message that will be
	// sent.
	messageLen int
	// messageCount is the number of test messages that will be sent.
	messageCount int
	// resumeSession controls whether a second connection should be tested
	// which attempts to resume the first session.
	resumeSession bool
	// resumeRenewedSession controls whether a third connection should be
	// tested which attempts to resume the second connection's session.
	resumeRenewedSession bool
	// expectResumeRejected, if true, specifies that the attempted
	// resumption must be rejected by the client. This is only valid for a
	// serverTest.
	expectResumeRejected bool
	// resumeConfig, if not nil, points to a Config to be used on
	// resumption. Unless newSessionsOnResume is set,
	// SessionTicketKey, ServerSessionCache, and
	// ClientSessionCache are copied from the initial connection's
	// config. If nil, the initial connection's config is used.
	resumeConfig *Config
	// newSessionsOnResume, if true, will cause resumeConfig to
	// use a different session resumption context.
	newSessionsOnResume bool
	// noSessionCache, if true, will cause the server to run without a
	// session cache.
	noSessionCache bool
	// sendPrefix sends a prefix on the socket before actually performing a
	// handshake.
	sendPrefix string
	// shimWritesFirst controls whether the shim sends an initial "hello"
	// message before doing a roundtrip with the runner.
	shimWritesFirst bool
	// readWithUnfinishedWrite behaves like shimWritesFirst, but the shim
	// does not complete the write until responding to the first runner
	// message.
	readWithUnfinishedWrite bool
	// shimShutsDown, if true, runs a test where the shim shuts down the
	// connection immediately after the handshake rather than echoing
	// messages from the runner. The runner will default to not sending
	// application data.
	shimShutsDown bool
	// renegotiate indicates the number of times the connection should be
	// renegotiated during the exchange.
	renegotiate int
	// sendHalfHelloRequest, if true, causes the server to send half a
	// HelloRequest when the handshake completes.
	sendHalfHelloRequest bool
	// renegotiateCiphers is a list of ciphersuite ids that will be
	// switched in just before renegotiation.
	renegotiateCiphers []uint16
	// replayWrites, if true, configures the underlying transport
	// to replay every write it makes in DTLS tests.
	replayWrites bool
	// damageFirstWrite, if true, configures the underlying transport to
	// damage the final byte of the first application data write.
	damageFirstWrite bool
	// exportKeyingMaterial, if non-zero, configures the test to exchange
	// keying material and verify they match.
	exportKeyingMaterial int
	exportLabel          string
	exportContext        string
	useExportContext     bool
	// flags, if not empty, contains a list of command-line flags that will
	// be passed to the shim program.
	flags []string
	// testTLSUnique, if true, causes the shim to send the tls-unique value
	// which will be compared against the expected value.
	testTLSUnique bool
	// sendEmptyRecords is the number of consecutive empty records to send
	// before each test message.
	sendEmptyRecords int
	// sendWarningAlerts is the number of consecutive warning alerts to send
	// before each test message.
	sendWarningAlerts int
	// sendUserCanceledAlerts is the number of consecutive user_canceled alerts to
	// send before each test message.
	sendUserCanceledAlerts int
	// sendBogusAlertType, if true, causes a bogus alert of invalid type to
	// be sent before each test message.
	sendBogusAlertType bool
	// sendKeyUpdates is the number of consecutive key updates to send
	// before and after the test message.
	sendKeyUpdates int
	// keyUpdateRequest is the KeyUpdateRequest value to send in KeyUpdate messages.
	keyUpdateRequest byte
	// shimSendsKeyUpdateBeforeRead indicates the shim should send a KeyUpdate
	// message before each read.
	shimSendsKeyUpdateBeforeRead bool
	// expectUnsolicitedKeyUpdate makes the test expect a one or more KeyUpdate
	// messages while reading data from the shim. Don't use this in combination
	// with any of the fields that send a KeyUpdate otherwise any received
	// KeyUpdate might not be as unsolicited as expected.
	expectUnsolicitedKeyUpdate bool
	// expectMessageDropped, if true, means the test message is expected to
	// be dropped by the client rather than echoed back.
	expectMessageDropped bool
	// shimPrefix is the prefix that the shim will send to the server.
	shimPrefix string
	// resumeShimPrefix is the prefix that the shim will send to the server on a
	// resumption.
	resumeShimPrefix string
	// exportTrafficSecrets, if true, configures the test to export the TLS 1.3
	// traffic secrets and confirms that they match.
	exportTrafficSecrets bool
	// skipTransportParamsConfig, if true, will skip automatic configuration of
	// sending QUIC transport parameters when protocol == quic.
	skipTransportParamsConfig bool
	// skipQUICALPNConfig, if true, will skip automatic configuration of
	// sending a fake ALPN when protocol == quic.
	skipQUICALPNConfig bool
	// earlyData, if true, configures default settings for an early data test.
	// expectEarlyDataRejected controls whether the test is for early data
	// accept or reject. In a client test, the shim will be configured to send
	// an initial write in early data which, on accept, the runner will enforce.
	// In a server test, the runner will send some default message in early
	// data, which the shim is expected to echo in half-RTT.
	earlyData bool
	// expectEarlyDataRejected, if earlyData is true, is whether early data is
	// expected to be rejected. In a client test, this controls whether the shim
	// should retry for early rejection. In a server test, this is whether the
	// test expects the shim to reject early data.
	expectEarlyDataRejected bool
	// skipSplitHandshake, if true, will skip the generation of a split
	// handshake copy of the test.
	skipSplitHandshake bool
	// skipHints, if true, will skip the generation of a handshake hints copy of
	// the test.
	skipHints bool
	// skipVersionNameCheck, if true, will skip the consistency check between
	// test name and the versions.
	skipVersionNameCheck bool
	// shimCertificate, if not nil, is the default credential which should be
	// configured at the shim. If set, it must be an X.509 credential.
	shimCertificate *Credential
	// handshakerCertificate, if not nil, overrides the default credential which
	// on the handshaker.
	handshakerCertificate *Credential
	// shimCredentials is a list of credentials which should be configured at
	// the shim. It differs from shimCertificate only in whether the old or
	// new APIs are used.
	shimCredentials       []*Credential
	resumeShimCredentials []*Credential
}

var testCases []testCase

func appendTranscript(path string, data []byte) error {
	if len(data) == 0 {
		return nil
	}

	settings, err := os.ReadFile(path)
	if err != nil {
		if !os.IsNotExist(err) {
			return err
		}
		// If the shim aborted before writing a file, use a default
		// settings block, so the transcript is still somewhat valid.
		settings = []byte{0, 0} // kDataTag
	}

	settings = append(settings, data...)
	return os.WriteFile(path, settings, 0644)
}

// A timeoutConn implements an idle timeout on each Read and Write operation.
type timeoutConn struct {
	net.Conn
	timeout time.Duration
}

func (t *timeoutConn) Read(b []byte) (int, error) {
	if !*useGDB {
		if err := t.SetReadDeadline(time.Now().Add(t.timeout)); err != nil {
			return 0, err
		}
	}
	return t.Conn.Read(b)
}

func (t *timeoutConn) Write(b []byte) (int, error) {
	if !*useGDB {
		if err := t.SetWriteDeadline(time.Now().Add(t.timeout)); err != nil {
			return 0, err
		}
	}
	return t.Conn.Write(b)
}

func makeTestMessage(msgIdx int, messageLen int) []byte {
	testMessage := make([]byte, messageLen)
	for i := range testMessage {
		testMessage[i] = 0x42 ^ byte(msgIdx)
	}
	return testMessage
}

func expectedReply(b []byte) []byte {
	ret := make([]byte, len(b))
	for i, v := range b {
		ret[i] = v ^ 0xff
	}
	return ret
}

func doExchange(test *testCase, config *Config, conn net.Conn, isResume bool, transcripts *[][]byte, num int) error {
	if !test.noSessionCache {
		if config.ClientSessionCache == nil {
			config.ClientSessionCache = NewLRUClientSessionCache(1)
		}
		if config.ServerSessionCache == nil {
			config.ServerSessionCache = NewLRUServerSessionCache(1)
		}
	}
	if test.testType != clientTest {
		// Supply a ServerName to ensure a constant session cache key,
		// rather than falling back to net.Conn.RemoteAddr.
		if len(config.ServerName) == 0 {
			config.ServerName = "test"
		}
	}

	if *fuzzer {
		config.Bugs.NullAllCiphers = true
	}
	if *deterministic {
		config.Time = func() time.Time { return time.Unix(1234, 1234) }
	}

	if !useDebugger() {
		conn = &timeoutConn{conn, *idleTimeout}
	}

	if test.protocol == dtls {
		config.Bugs.PacketAdaptor = newPacketAdaptor(conn)
		conn = config.Bugs.PacketAdaptor
	}

	if *flagDebug || len(*transcriptDir) != 0 {
		local, peer := "client", "server"
		if test.testType == clientTest {
			local, peer = peer, local
		}
		connDebug := &recordingConn{
			Conn:       conn,
			isDatagram: test.protocol == dtls,
			local:      local,
			peer:       peer,
		}
		conn = connDebug
		if *flagDebug {
			defer connDebug.WriteTo(os.Stdout)
		}
		if len(*transcriptDir) != 0 {
			defer func() {
				if num == len(*transcripts) {
					*transcripts = append(*transcripts, connDebug.Transcript())
				} else {
					panic("transcripts are out of sync")
				}
			}()

			// Record ClientHellos for the decode_client_hello_inner fuzzer.
			var clientHelloCount int
			config.Bugs.RecordClientHelloInner = func(encodedInner, outer []byte) error {
				name := fmt.Sprintf("%s-%d-%d", test.name, num, clientHelloCount)
				clientHelloCount++
				dir := filepath.Join(*transcriptDir, "decode_client_hello_inner")
				if err := os.MkdirAll(dir, 0755); err != nil {
					return err
				}
				bb := cryptobyte.NewBuilder(nil)
				addUint24LengthPrefixedBytes(bb, encodedInner)
				bb.AddBytes(outer)
				return os.WriteFile(filepath.Join(dir, name), bb.BytesOrPanic(), 0644)
			}
		}

		if config.Bugs.PacketAdaptor != nil {
			config.Bugs.PacketAdaptor.debug = connDebug
		}
	}
	if test.protocol == quic {
		config.Bugs.MockQUICTransport = newMockQUICTransport(conn)
		// The MockQUICTransport will panic if Read or Write is
		// called. When a MockQUICTransport is set, separate
		// methods should be used to actually read and write
		// records. By setting the conn to it here, it ensures
		// Read or Write aren't accidentally used instead of the
		// methods provided by MockQUICTransport.
		conn = config.Bugs.MockQUICTransport
	}

	if test.replayWrites {
		conn = newReplayAdaptor(conn)
	}

	var connDamage *damageAdaptor
	if test.damageFirstWrite {
		connDamage = newDamageAdaptor(conn)
		conn = connDamage
	}

	if test.sendPrefix != "" {
		if _, err := conn.Write([]byte(test.sendPrefix)); err != nil {
			return err
		}
	}

	var tlsConn *Conn
	if test.testType == clientTest {
		if test.protocol == dtls {
			tlsConn = DTLSServer(conn, config)
		} else {
			tlsConn = Server(conn, config)
		}
	} else {
		config.InsecureSkipVerify = true
		if test.protocol == dtls {
			tlsConn = DTLSClient(conn, config)
		} else {
			tlsConn = Client(conn, config)
		}
	}
	defer tlsConn.Close()

	if err := tlsConn.Handshake(); err != nil {
		return err
	}

	expectations := &test.expectations
	if isResume && test.resumeExpectations != nil {
		expectations = test.resumeExpectations
	}
	connState := tlsConn.ConnectionState()
	if vers := connState.Version; expectations.version != 0 && vers != expectations.version {
		return fmt.Errorf("got version %x, expected %x", vers, expectations.version)
	}

	if cipher := connState.CipherSuite; expectations.cipher != 0 && cipher != expectations.cipher {
		return fmt.Errorf("got cipher %x, expected %x", cipher, expectations.cipher)
	}
	if didResume := connState.DidResume; isResume && didResume == test.expectResumeRejected {
		return fmt.Errorf("didResume is %t, but we expected the opposite", didResume)
	}

	if expectations.channelID {
		channelID := connState.ChannelID
		if channelID == nil {
			return fmt.Errorf("no channel ID negotiated")
		}
		if channelID.Curve != channelIDKey.Curve ||
			channelIDKey.X.Cmp(channelIDKey.X) != 0 ||
			channelIDKey.Y.Cmp(channelIDKey.Y) != 0 {
			return fmt.Errorf("incorrect channel ID")
		}
	} else if connState.ChannelID != nil {
		return fmt.Errorf("channel ID unexpectedly negotiated")
	}

	if expected := expectations.nextProto; expected != "" {
		if actual := connState.NegotiatedProtocol; actual != expected {
			return fmt.Errorf("next proto mismatch: got %s, wanted %s", actual, expected)
		}
	}

	if expectations.noNextProto {
		if actual := connState.NegotiatedProtocol; actual != "" {
			return fmt.Errorf("got unexpected next proto %s", actual)
		}
	}

	if expectations.nextProtoType != 0 {
		if (expectations.nextProtoType == alpn) != connState.NegotiatedProtocolFromALPN {
			return fmt.Errorf("next proto type mismatch")
		}
	}

	if expectations.peerApplicationSettings != nil {
		if !connState.HasApplicationSettings {
			return errors.New("application settings should have been negotiated")
		}
		if !bytes.Equal(connState.PeerApplicationSettings, expectations.peerApplicationSettings) {
			return fmt.Errorf("peer application settings mismatch: got %q, wanted %q", connState.PeerApplicationSettings, expectations.peerApplicationSettings)
		}
	} else if connState.HasApplicationSettings {
		return errors.New("application settings unexpectedly negotiated")
	}

	if expectations.peerApplicationSettingsOld != nil {
		if !connState.HasApplicationSettingsOld {
			return errors.New("old application settings should have been negotiated")
		}
		if !bytes.Equal(connState.PeerApplicationSettingsOld, expectations.peerApplicationSettingsOld) {
			return fmt.Errorf("old peer application settings mismatch: got %q, wanted %q", connState.PeerApplicationSettingsOld, expectations.peerApplicationSettingsOld)
		}
	} else if connState.HasApplicationSettingsOld {
		return errors.New("old application settings unexpectedly negotiated")
	}

	if p := connState.SRTPProtectionProfile; p != expectations.srtpProtectionProfile {
		return fmt.Errorf("SRTP profile mismatch: got %d, wanted %d", p, expectations.srtpProtectionProfile)
	}

	if expected := expectations.peerSignatureAlgorithm; expected != 0 && expected != connState.PeerSignatureAlgorithm {
		return fmt.Errorf("expected peer to use signature algorithm %04x, but got %04x", expected, connState.PeerSignatureAlgorithm)
	}

	if expected := expectations.curveID; expected != 0 && expected != connState.CurveID {
		return fmt.Errorf("expected peer to use curve %04x, but got %04x", expected, connState.CurveID)
	}

	if expected := expectations.peerCertificate; expected != nil {
		if len(connState.PeerCertificates) != len(expected.Certificate) {
			return fmt.Errorf("expected peer to send %d certificates, but got %d", len(connState.PeerCertificates), len(expected.Certificate))
		}
		for i, cert := range connState.PeerCertificates {
			if !bytes.Equal(cert.Raw, expected.Certificate[i]) {
				return fmt.Errorf("peer certificate %d did not match", i+1)
			}
		}

		if !bytes.Equal(connState.OCSPResponse, expected.OCSPStaple) {
			return fmt.Errorf("peer OCSP response did not match")
		}

		if !bytes.Equal(connState.SCTList, expected.SignedCertificateTimestampList) {
			return fmt.Errorf("peer SCT list did not match")
		}

		if expected.Type == CredentialTypeDelegated {
			if connState.PeerDelegatedCredential == nil {
				return fmt.Errorf("peer unexpectedly did not use delegated credentials")
			}
			if !bytes.Equal(expected.DelegatedCredential, connState.PeerDelegatedCredential) {
				return fmt.Errorf("peer delegated credential did not match")
			}
		} else if connState.PeerDelegatedCredential != nil {
			return fmt.Errorf("peer unexpectedly used delegated credentials")
		}
	}

	if len(expectations.quicTransportParams) > 0 {
		if !bytes.Equal(expectations.quicTransportParams, connState.QUICTransportParams) {
			return errors.New("Peer did not send expected QUIC transport params")
		}
	}

	if len(expectations.quicTransportParamsLegacy) > 0 {
		if !bytes.Equal(expectations.quicTransportParamsLegacy, connState.QUICTransportParamsLegacy) {
			return errors.New("Peer did not send expected legacy QUIC transport params")
		}
	}

	if expectations.echAccepted {
		if !connState.ECHAccepted {
			return errors.New("tls: server did not accept ECH")
		}
	} else {
		if connState.ECHAccepted {
			return errors.New("tls: server unexpectedly accepted ECH")
		}
	}

	if test.exportKeyingMaterial > 0 {
		actual := make([]byte, test.exportKeyingMaterial)
		if _, err := io.ReadFull(tlsConn, actual); err != nil {
			return err
		}
		expected, err := tlsConn.ExportKeyingMaterial(test.exportKeyingMaterial, []byte(test.exportLabel), []byte(test.exportContext), test.useExportContext)
		if err != nil {
			return err
		}
		if !bytes.Equal(actual, expected) {
			return fmt.Errorf("keying material mismatch; got %x, wanted %x", actual, expected)
		}
	}

	if test.exportTrafficSecrets {
		secretLenBytes := make([]byte, 2)
		if _, err := io.ReadFull(tlsConn, secretLenBytes); err != nil {
			return err
		}
		secretLen := binary.LittleEndian.Uint16(secretLenBytes)

		theirReadSecret := make([]byte, secretLen)
		theirWriteSecret := make([]byte, secretLen)
		if _, err := io.ReadFull(tlsConn, theirReadSecret); err != nil {
			return err
		}
		if _, err := io.ReadFull(tlsConn, theirWriteSecret); err != nil {
			return err
		}

		myReadSecret := tlsConn.in.trafficSecret
		myWriteSecret := tlsConn.out.trafficSecret
		if !bytes.Equal(myWriteSecret, theirReadSecret) {
			return fmt.Errorf("read traffic-secret mismatch; got %x, wanted %x", theirReadSecret, myWriteSecret)
		}
		if !bytes.Equal(myReadSecret, theirWriteSecret) {
			return fmt.Errorf("write traffic-secret mismatch; got %x, wanted %x", theirWriteSecret, myReadSecret)
		}
	}

	if test.testTLSUnique {
		var peersValue [12]byte
		if _, err := io.ReadFull(tlsConn, peersValue[:]); err != nil {
			return err
		}
		expected := tlsConn.ConnectionState().TLSUnique
		if !bytes.Equal(peersValue[:], expected) {
			return fmt.Errorf("tls-unique mismatch: peer sent %x, but %x was expected", peersValue[:], expected)
		}
	}

	if test.sendHalfHelloRequest {
		tlsConn.SendHalfHelloRequest()
	}

	shimPrefix := test.shimPrefix
	if isResume {
		shimPrefix = test.resumeShimPrefix
	}
	if test.shimWritesFirst || test.readWithUnfinishedWrite {
		shimPrefix = shimInitialWrite
	}
	if test.renegotiate > 0 {
		// If readWithUnfinishedWrite is set, the shim prefix will be
		// available later.
		if shimPrefix != "" && !test.readWithUnfinishedWrite {
			buf := make([]byte, len(shimPrefix))
			_, err := io.ReadFull(tlsConn, buf)
			if err != nil {
				return err
			}
			if string(buf) != shimPrefix {
				return fmt.Errorf("bad initial message %v vs %v", string(buf), shimPrefix)
			}
			shimPrefix = ""
		}

		if test.renegotiateCiphers != nil {
			config.CipherSuites = test.renegotiateCiphers
		}
		for i := 0; i < test.renegotiate; i++ {
			if err := tlsConn.Renegotiate(); err != nil {
				return err
			}
		}
	} else if test.renegotiateCiphers != nil {
		panic("renegotiateCiphers without renegotiate")
	}

	if test.damageFirstWrite {
		connDamage.setDamage(true)
		if _, err := tlsConn.Write([]byte("DAMAGED WRITE")); err != nil {
			return err
		}
		connDamage.setDamage(false)
	}

	messageLen := test.messageLen
	if messageLen < 0 {
		if test.protocol == dtls {
			return fmt.Errorf("messageLen < 0 not supported for DTLS tests")
		}
		// Read until EOF.
		_, err := io.Copy(io.Discard, tlsConn)
		return err
	}
	if messageLen == 0 {
		messageLen = 32
	}

	messageCount := test.messageCount
	// shimShutsDown sets the default message count to zero.
	if messageCount == 0 && !test.shimShutsDown {
		messageCount = 1
	}

	for j := 0; j < messageCount; j++ {
		for i := 0; i < test.sendKeyUpdates; i++ {
			if err := tlsConn.SendKeyUpdate(test.keyUpdateRequest); err != nil {
				return err
			}
		}

		for i := 0; i < test.sendEmptyRecords; i++ {
			if _, err := tlsConn.Write(nil); err != nil {
				return err
			}
		}

		for i := 0; i < test.sendWarningAlerts; i++ {
			if err := tlsConn.SendAlert(alertLevelWarning, alertUnexpectedMessage); err != nil {
				return err
			}
		}

		for i := 0; i < test.sendUserCanceledAlerts; i++ {
			if err := tlsConn.SendAlert(alertLevelWarning, alertUserCanceled); err != nil {
				return err
			}
		}

		if test.sendBogusAlertType {
			if err := tlsConn.SendAlert(0x42, alertUnexpectedMessage); err != nil {
				return err
			}
		}

		if test.shimSendsKeyUpdateBeforeRead {
			if err := tlsConn.ReadKeyUpdate(); err != nil {
				return err
			}
		}

		testMessage := makeTestMessage(j, messageLen)
		if _, err := tlsConn.Write(testMessage); err != nil {
			return err
		}

		// Consume the shim prefix if needed.
		if shimPrefix != "" {
			buf := make([]byte, len(shimPrefix))
			_, err := io.ReadFull(tlsConn, buf)
			if err != nil {
				return err
			}
			if string(buf) != shimPrefix {
				return fmt.Errorf("bad initial message %v vs %v", string(buf), shimPrefix)
			}
			shimPrefix = ""
		}

		if test.shimShutsDown || test.expectMessageDropped {
			// The shim will not respond.
			continue
		}

		// Process the KeyUpdate reply. However many KeyUpdates the runner
		// sends, the shim should respond only once.
		if test.sendKeyUpdates > 0 && test.keyUpdateRequest == keyUpdateRequested {
			if err := tlsConn.ReadKeyUpdate(); err != nil {
				return err
			}
		}

		buf := make([]byte, len(testMessage))
		if test.protocol == dtls {
			bufTmp := make([]byte, len(buf)+1)
			n, err := tlsConn.Read(bufTmp)
			if err != nil {
				return err
			}
			if config.Bugs.SplitAndPackAppData {
				m, err := tlsConn.Read(bufTmp[n:])
				if err != nil {
					return err
				}
				n += m
			}
			if n != len(buf) {
				return fmt.Errorf("bad reply; length mismatch (%d vs %d)", n, len(buf))
			}
			copy(buf, bufTmp)
		} else {
			_, err := io.ReadFull(tlsConn, buf)
			if err != nil {
				return err
			}
		}

		if expected := expectedReply(testMessage); !bytes.Equal(buf, expected) {
			return fmt.Errorf("bad reply contents; got %x and wanted %x", buf, expected)
		}

		if seen := tlsConn.keyUpdateSeen; seen != test.expectUnsolicitedKeyUpdate {
			return fmt.Errorf("keyUpdateSeen (%t) != expectUnsolicitedKeyUpdate", seen)
		}
	}

	// The shim will end attempting to read, sending one last KeyUpdate. Consume
	// the KeyUpdate before closing the connection.
	if test.shimSendsKeyUpdateBeforeRead {
		if err := tlsConn.ReadKeyUpdate(); err != nil {
			return err
		}
	}

	return nil
}

const xtermSize = "140x50"

func valgrindOf(dbAttach bool, path string, args ...string) *exec.Cmd {
	valgrindArgs := []string{"--error-exitcode=99", "--track-origins=yes", "--leak-check=full", "--quiet"}
	if dbAttach {
		valgrindArgs = append(valgrindArgs, "--db-attach=yes", "--db-command=xterm -geometry "+xtermSize+" -e gdb -nw %f %p")
	}
	valgrindArgs = append(valgrindArgs, path)
	valgrindArgs = append(valgrindArgs, args...)

	return exec.Command("valgrind", valgrindArgs...)
}

func gdbOf(path string, args ...string) *exec.Cmd {
	xtermArgs := []string{"-geometry", xtermSize, "-e", "gdb", "--args"}
	xtermArgs = append(xtermArgs, path)
	xtermArgs = append(xtermArgs, args...)

	return exec.Command("xterm", xtermArgs...)
}

func lldbOf(path string, args ...string) *exec.Cmd {
	xtermArgs := []string{"-geometry", xtermSize, "-e", "lldb", "--"}
	xtermArgs = append(xtermArgs, path)
	xtermArgs = append(xtermArgs, args...)

	return exec.Command("xterm", xtermArgs...)
}

func rrOf(path string, args ...string) *exec.Cmd {
	rrArgs := []string{"record", path}
	rrArgs = append(rrArgs, args...)
	return exec.Command("rr", rrArgs...)
}

func removeFirstLineIfSuffix(s, suffix string) string {
	idx := strings.IndexByte(s, '\n')
	if idx < 0 {
		return s
	}
	if strings.HasSuffix(s[:idx], suffix) {
		return s[idx+1:]
	}
	return s
}

var (
	errMoreMallocs   = errors.New("child process did not exhaust all allocation calls")
	errUnimplemented = errors.New("child process does not implement needed flags")
)

type shimProcess struct {
	cmd *exec.Cmd
	// done is closed when the process has exited. At that point, childErr may be
	// read for the result.
	done           chan struct{}
	childErr       error
	listener       *shimListener
	stdout, stderr bytes.Buffer
}

// newShimProcess starts a new shim with the specified executable, flags, and
// environment. It internally creates a TCP listener and adds the the -port
// flag.
func newShimProcess(dispatcher *shimDispatcher, shimPath string, flags []string, env []string) (*shimProcess, error) {
	listener, err := dispatcher.NewShim()
	if err != nil {
		return nil, err
	}

	shim := &shimProcess{listener: listener}
	cmdFlags := []string{
		"-port", strconv.Itoa(listener.Port()),
		"-shim-id", strconv.FormatUint(listener.ShimID(), 10),
	}
	if listener.IsIPv6() {
		cmdFlags = append(cmdFlags, "-ipv6")
	}
	cmdFlags = append(cmdFlags, flags...)

	if *useValgrind {
		shim.cmd = valgrindOf(false, shimPath, cmdFlags...)
	} else if *useGDB {
		shim.cmd = gdbOf(shimPath, cmdFlags...)
	} else if *useLLDB {
		shim.cmd = lldbOf(shimPath, cmdFlags...)
	} else if *useRR {
		shim.cmd = rrOf(shimPath, cmdFlags...)
	} else {
		shim.cmd = exec.Command(shimPath, cmdFlags...)
	}
	shim.cmd.Stdin = os.Stdin
	shim.cmd.Stdout = &shim.stdout
	shim.cmd.Stderr = &shim.stderr
	shim.cmd.Env = env

	if err := shim.cmd.Start(); err != nil {
		shim.listener.Close()
		return nil, err
	}

	shim.done = make(chan struct{})
	go func() {
		shim.childErr = shim.cmd.Wait()
		shim.listener.Close()
		close(shim.done)
	}()
	return shim, nil
}

// accept returns a new TCP connection with the shim process, or returns an
// error on timeout or shim exit.
func (s *shimProcess) accept() (net.Conn, error) {
	var deadline time.Time
	if !useDebugger() {
		deadline = time.Now().Add(*idleTimeout)
	}
	return s.listener.Accept(deadline)
}

// wait finishes the test and waits for the shim process to exit.
func (s *shimProcess) wait() error {
	// Close the listener now. This is to avoid hangs if the shim tries to open
	// more connections than expected.
	s.listener.Close()

	if !useDebugger() {
		waitTimeout := time.AfterFunc(*idleTimeout, func() {
			s.cmd.Process.Kill()
		})
		defer waitTimeout.Stop()
	}

	<-s.done
	return s.childErr
}

// close releases resources associated with the shimProcess. This is safe to
// call before or after |wait|.
func (s *shimProcess) close() {
	s.listener.Close()
	s.cmd.Process.Kill()
}

func doExchanges(test *testCase, shim *shimProcess, resumeCount int, transcripts *[][]byte) error {
	config := test.config
	if *deterministic {
		config.Rand = &deterministicRand{}
	}

	conn, err := shim.accept()
	if err != nil {
		return err
	}
	err = doExchange(test, &config, conn, false /* not a resumption */, transcripts, 0)
	conn.Close()
	if err != nil {
		return err
	}

	nextTicketKey := config.SessionTicketKey
	for i := 0; i < resumeCount; i++ {
		var resumeConfig Config
		if test.resumeConfig != nil {
			resumeConfig = *test.resumeConfig
			resumeConfig.Rand = config.Rand
			if resumeConfig.Credential == nil {
				resumeConfig.Credential = config.Credential
			}
		} else {
			resumeConfig = config
		}

		if test.newSessionsOnResume {
			resumeConfig.ClientSessionCache = nil
			resumeConfig.ServerSessionCache = nil
			if _, err := resumeConfig.rand().Read(resumeConfig.SessionTicketKey[:]); err != nil {
				return err
			}
		} else {
			resumeConfig.ClientSessionCache = config.ClientSessionCache
			resumeConfig.ServerSessionCache = config.ServerSessionCache
			// Rotate the ticket keys between each connection, with each connection
			// encrypting with next connection's keys. This ensures that we test
			// the renewed sessions.
			resumeConfig.SessionTicketKey = nextTicketKey
			if _, err := resumeConfig.rand().Read(nextTicketKey[:]); err != nil {
				return err
			}
			resumeConfig.Bugs.EncryptSessionTicketKey = &nextTicketKey
		}

		var connResume net.Conn
		connResume, err = shim.accept()
		if err != nil {
			return err
		}
		err = doExchange(test, &resumeConfig, connResume, true /* resumption */, transcripts, i+1)
		connResume.Close()
		if err != nil {
			return err
		}
	}

	return nil
}

func translateExpectedError(errorStr string) string {
	if translated, ok := shimConfig.ErrorMap[errorStr]; ok {
		return translated
	}

	if *looseErrors {
		return ""
	}

	return errorStr
}

// shimInitialWrite is the data we expect from the shim when the
// -shim-writes-first flag is used.
const shimInitialWrite = "hello"

func appendCredentialFlags(flags []string, cred *Credential, prefix string, newCredential bool) []string {
	if newCredential {
		switch cred.Type {
		case CredentialTypeX509:
			flags = append(flags, prefix+"-new-x509-credential")
		case CredentialTypeDelegated:
			flags = append(flags, prefix+"-new-delegated-credential")
		case CredentialTypeSPAKE2PlusV1:
			flags = append(flags, prefix+"-new-spake2plusv1-credential")
		default:
			panic(fmt.Errorf("unknown credential type %d", cred.Type))
		}
	} else if cred.Type != CredentialTypeX509 {
		panic("default credential must be X.509")
	}

	handleBase64Field := func(flag string, value []byte) {
		if len(value) != 0 {
			flags = append(flags, fmt.Sprintf("%s-%s", prefix, flag), base64FlagValue(value))
		}
	}

	if len(cred.ChainPath) != 0 {
		flags = append(flags, prefix+"-cert-file", cred.ChainPath)
	}
	if len(cred.KeyPath) != 0 {
		flags = append(flags, prefix+"-key-file", cred.KeyPath)
	}
	handleBase64Field("ocsp-response", cred.OCSPStaple)
	handleBase64Field("signed-cert-timestamps", cred.SignedCertificateTimestampList)
	for _, sigAlg := range cred.SignatureAlgorithms {
		flags = append(flags, prefix+"-signing-prefs", strconv.Itoa(int(sigAlg)))
	}
	handleBase64Field("delegated-credential", cred.DelegatedCredential)
	if cred.MustMatchIssuer {
		flags = append(flags, prefix+"-must-match-issuer")
	}
	handleBase64Field("pake-context", cred.PAKEContext)
	handleBase64Field("pake-client-id", cred.PAKEClientID)
	handleBase64Field("pake-server-id", cred.PAKEServerID)
	handleBase64Field("pake-password", cred.PAKEPassword)
	if cred.WrongPAKERole {
		flags = append(flags, prefix+"-wrong-pake-role")
	}
	return flags
}

func runTest(dispatcher *shimDispatcher, statusChan chan statusMsg, test *testCase, shimPath string, mallocNumToFail int64) error {
	// Help debugging panics on the Go side.
	defer func() {
		if r := recover(); r != nil {
			fmt.Fprintf(os.Stderr, "Test '%s' panicked.\n", test.name)
			panic(r)
		}
	}()

	var flags []string
	if len(*shimExtraFlags) > 0 {
		flags = strings.Split(*shimExtraFlags, ";")
	}
	if test.testType == serverTest {
		flags = append(flags, "-server")
	}

	// Configure the default credential.
	shimCertificate := test.shimCertificate
	if shimCertificate == nil && len(test.shimCredentials) == 0 && len(test.resumeShimCredentials) == 0 && test.testType == serverTest && len(test.config.PreSharedKey) == 0 {
		shimCertificate = &rsaCertificate
	}
	if shimCertificate != nil {
		var shimPrefix string
		if test.handshakerCertificate != nil {
			shimPrefix = "-on-shim"
		}
		flags = appendCredentialFlags(flags, shimCertificate, shimPrefix, false)
	}
	if test.handshakerCertificate != nil {
		flags = appendCredentialFlags(flags, test.handshakerCertificate, "-on-handshaker", false)
	}

	// Configure any additional credentials.
	for _, cred := range test.shimCredentials {
		flags = appendCredentialFlags(flags, cred, "", true)
	}
	for _, cred := range test.resumeShimCredentials {
		flags = appendCredentialFlags(flags, cred, "-on-resume", true)
	}

	if test.protocol == dtls {
		flags = append(flags, "-dtls")
	} else if test.protocol == quic {
		flags = append(flags, "-quic")
		if !test.skipTransportParamsConfig {
			test.config.QUICTransportParams = []byte{1, 2}
			test.config.QUICTransportParamsUseLegacyCodepoint = QUICUseCodepointStandard
			if test.resumeConfig != nil {
				test.resumeConfig.QUICTransportParams = []byte{1, 2}
				test.resumeConfig.QUICTransportParamsUseLegacyCodepoint = QUICUseCodepointStandard
			}
			test.expectations.quicTransportParams = []byte{3, 4}
			if test.resumeExpectations != nil {
				test.resumeExpectations.quicTransportParams = []byte{3, 4}
			}
			useCodepointFlag := "0"
			if test.config.QUICTransportParamsUseLegacyCodepoint == QUICUseCodepointLegacy {
				useCodepointFlag = "1"
			}
			flags = append(flags,
				"-quic-transport-params",
				base64FlagValue([]byte{3, 4}),
				"-expect-quic-transport-params",
				base64FlagValue([]byte{1, 2}),
				"-quic-use-legacy-codepoint", useCodepointFlag)
		}
		if !test.skipQUICALPNConfig {
			flags = append(flags,
				[]string{
					"-advertise-alpn", "\x03foo",
					"-select-alpn", "foo",
					"-expect-alpn", "foo",
				}...)
			test.config.NextProtos = []string{"foo"}
			if test.resumeConfig != nil {
				test.resumeConfig.NextProtos = []string{"foo"}
			}
			test.expectations.nextProto = "foo"
			test.expectations.nextProtoType = alpn
			if test.resumeExpectations != nil {
				test.resumeExpectations.nextProto = "foo"
				test.resumeExpectations.nextProtoType = alpn
			}
		}
	}

	if test.earlyData {
		if !test.resumeSession {
			panic("earlyData set without resumeSession in " + test.name)
		}

		resumeConfig := test.resumeConfig
		if resumeConfig == nil {
			resumeConfig = &test.config
		}
		if test.expectEarlyDataRejected {
			flags = append(flags, "-on-resume-expect-reject-early-data")
		} else {
			flags = append(flags, "-on-resume-expect-accept-early-data")
		}

		if test.protocol == quic {
			// QUIC requires an early data context string.
			flags = append(flags, "-quic-early-data-context", "context")
		}

		flags = append(flags, "-enable-early-data")
		if test.testType == clientTest {
			// Configure the runner with default maximum early data.
			flags = append(flags, "-expect-ticket-supports-early-data")
			if test.config.MaxEarlyDataSize == 0 {
				test.config.MaxEarlyDataSize = 16384
			}
			if resumeConfig.MaxEarlyDataSize == 0 {
				resumeConfig.MaxEarlyDataSize = 16384
			}

			// In DTLS 1.3, we're setting flags to configure the client to attempt
			// sending early data, but we expect it to realize that it's incapable
			// of supporting early data and not send any.
			if test.protocol != dtls {
				// Configure the shim to send some data in early data.
				flags = append(flags, "-on-resume-shim-writes-first")
				if resumeConfig.Bugs.ExpectEarlyData == nil {
					resumeConfig.Bugs.ExpectEarlyData = [][]byte{[]byte(shimInitialWrite)}
				}
			}
		} else {
			// By default, send some early data and expect half-RTT data response.
			if resumeConfig.Bugs.SendEarlyData == nil {
				resumeConfig.Bugs.SendEarlyData = [][]byte{{1, 2, 3, 4}}
			}
			if resumeConfig.Bugs.ExpectHalfRTTData == nil {
				resumeConfig.Bugs.ExpectHalfRTTData = [][]byte{{254, 253, 252, 251}}
			}
			resumeConfig.Bugs.ExpectEarlyDataAccepted = !test.expectEarlyDataRejected
		}
	}

	var resumeCount int
	if test.resumeSession {
		resumeCount++
		if test.resumeRenewedSession {
			resumeCount++
		}
	}

	if resumeCount > 0 {
		flags = append(flags, "-resume-count", strconv.Itoa(resumeCount))
	}

	if test.shimWritesFirst {
		flags = append(flags, "-shim-writes-first")
	}

	if test.readWithUnfinishedWrite {
		flags = append(flags, "-read-with-unfinished-write")
	}

	if test.shimShutsDown {
		flags = append(flags, "-shim-shuts-down")
	}

	if test.exportKeyingMaterial > 0 {
		flags = append(flags, "-export-keying-material", strconv.Itoa(test.exportKeyingMaterial))
		if test.useExportContext {
			flags = append(flags, "-use-export-context")
		}
	}
	if test.exportKeyingMaterial > 0 {
		flags = append(flags, "-export-label", test.exportLabel)
		flags = append(flags, "-export-context", test.exportContext)
	}

	if test.exportTrafficSecrets {
		flags = append(flags, "-export-traffic-secrets")
	}

	if test.expectResumeRejected {
		flags = append(flags, "-expect-session-miss")
	}

	if test.testTLSUnique {
		flags = append(flags, "-tls-unique")
	}

	if test.shimSendsKeyUpdateBeforeRead {
		flags = append(flags, "-key-update-before-read")
	}

	if *waitForDebugger {
		flags = append(flags, "-wait-for-debugger")
	}

	var transcriptPrefix string
	var transcripts [][]byte
	if len(*transcriptDir) != 0 {
		protocol := "tls"
		if test.protocol == dtls {
			protocol = "dtls"
		} else if test.protocol == quic {
			protocol = "quic"
		}

		side := "client"
		if test.testType == serverTest {
			side = "server"
		}

		dir := filepath.Join(*transcriptDir, protocol, side)
		if err := os.MkdirAll(dir, 0755); err != nil {
			return err
		}
		transcriptPrefix = filepath.Join(dir, test.name+"-")
		flags = append(flags, "-write-settings", transcriptPrefix)
	}

	if test.testType == clientTest && test.config.Credential == nil {
		test.config.Credential = &rsaCertificate
	}
	if test.config.Credential != nil {
		flags = append(flags, "-trust-cert", test.config.Credential.RootPath)
	}

	flags = append(flags, test.flags...)

	var env []string
	if mallocNumToFail >= 0 {
		env = os.Environ()
		env = append(env, "MALLOC_NUMBER_TO_FAIL="+strconv.FormatInt(mallocNumToFail, 10))
		if *mallocTestDebug {
			env = append(env, "MALLOC_BREAK_ON_FAIL=1")
		}
		env = append(env, "_MALLOC_CHECK=1")
	}

	shim, err := newShimProcess(dispatcher, shimPath, flags, env)
	if err != nil {
		return err
	}
	statusChan <- statusMsg{test: test, statusType: statusShimStarted, pid: shim.cmd.Process.Pid}
	defer shim.close()

	localErr := doExchanges(test, shim, resumeCount, &transcripts)
	childErr := shim.wait()

	// Now that the shim has exited, all the settings files have been
	// written. Append the saved transcripts.
	for i, transcript := range transcripts {
		if err := appendTranscript(transcriptPrefix+strconv.Itoa(i), transcript); err != nil {
			return err
		}
	}

	var isValgrindError, mustFail bool
	if exitError, ok := childErr.(*exec.ExitError); ok {
		switch exitError.Sys().(syscall.WaitStatus).ExitStatus() {
		case 88:
			return errMoreMallocs
		case 89:
			return errUnimplemented
		case 90:
			mustFail = true
		case 99:
			isValgrindError = true
		}
	}

	// Account for Windows line endings.
	stdout := strings.Replace(shim.stdout.String(), "\r\n", "\n", -1)
	stderr := strings.Replace(shim.stderr.String(), "\r\n", "\n", -1)

	// Work around an NDK / Android bug. The NDK r16 sometimes generates
	// binaries with the DF_1_PIE, which the runtime linker on Android N
	// complains about. The next NDK revision should work around this but,
	// in the meantime, strip its error out.
	//
	// https://github.com/android-ndk/ndk/issues/602
	// https://android-review.googlesource.com/c/platform/bionic/+/259790
	// https://android-review.googlesource.com/c/toolchain/binutils/+/571550
	//
	// Remove this after switching to the r17 NDK.
	stderr = removeFirstLineIfSuffix(stderr, ": unsupported flags DT_FLAGS_1=0x8000001")

	// Separate the errors from the shim and those from tools like
	// AddressSanitizer.
	var extraStderr string
	if stderrParts := strings.SplitN(stderr, "--- DONE ---\n", 2); len(stderrParts) == 2 {
		stderr = stderrParts[0]
		extraStderr = stderrParts[1]
	}

	failed := localErr != nil || childErr != nil
	expectedError := translateExpectedError(test.expectedError)
	correctFailure := len(expectedError) == 0 || strings.Contains(stderr, expectedError)

	localErrString := "none"
	if localErr != nil {
		localErrString = localErr.Error()
	}
	if len(test.expectedLocalError) != 0 {
		correctFailure = correctFailure && strings.Contains(localErrString, test.expectedLocalError)
	}

	if failed != test.shouldFail || failed && !correctFailure || mustFail {
		childErrString := "none"
		if childErr != nil {
			childErrString = childErr.Error()
		}

		var msg string
		switch {
		case failed && !test.shouldFail:
			msg = "unexpected failure"
		case !failed && test.shouldFail:
			msg = fmt.Sprintf("unexpected success (wanted failure with %q / %q)", expectedError, test.expectedLocalError)
		case failed && !correctFailure:
			msg = fmt.Sprintf("bad error (wanted %q / %q)", expectedError, test.expectedLocalError)
		case mustFail:
			msg = "test failure"
		default:
			panic("internal error")
		}

		return fmt.Errorf("%s: local error %q, child error %q, stdout:\n%s\nstderr:\n%s\n%s", msg, localErrString, childErrString, stdout, stderr, extraStderr)
	}

	if len(extraStderr) > 0 || (!failed && len(stderr) > 0) {
		return fmt.Errorf("unexpected error output:\n%s\n%s", stderr, extraStderr)
	}

	if *useValgrind && isValgrindError {
		return fmt.Errorf("valgrind error:\n%s\n%s", stderr, extraStderr)
	}

	return nil
}

type tlsVersion struct {
	name string
	// version is the protocol version.
	version uint16
	// excludeFlag is the legacy shim flag to disable the version.
	excludeFlag string
	hasDTLS     bool
	hasQUIC     bool
	// versionDTLS, if non-zero, is the DTLS-specific representation of the version.
	versionDTLS uint16
	// versionWire, if non-zero, is the wire representation of the
	// version. Otherwise the wire version is the protocol version or
	// versionDTLS.
	versionWire uint16
}

func (vers tlsVersion) String() string {
	return vers.name
}

func (vers tlsVersion) shimFlag(protocol protocol) string {
	// The shim uses the protocol version in its public API, but uses the
	// DTLS-specific version if it exists.
	if protocol == dtls && vers.versionDTLS != 0 {
		return strconv.Itoa(int(vers.versionDTLS))
	}
	return strconv.Itoa(int(vers.version))
}

func (vers tlsVersion) wire(protocol protocol) uint16 {
	if protocol == dtls && vers.versionDTLS != 0 {
		return vers.versionDTLS
	}
	if vers.versionWire != 0 {
		return vers.versionWire
	}
	return vers.version
}

func (vers tlsVersion) supportsProtocol(protocol protocol) bool {
	if protocol == dtls {
		return vers.hasDTLS
	}
	if protocol == quic {
		return vers.hasQUIC
	}
	return true
}

var tlsVersions = []tlsVersion{
	{
		name:        "TLS1",
		version:     VersionTLS10,
		excludeFlag: "-no-tls1",
		hasDTLS:     true,
		versionDTLS: VersionDTLS10,
	},
	{
		name:        "TLS11",
		version:     VersionTLS11,
		excludeFlag: "-no-tls11",
	},
	{
		name:        "TLS12",
		version:     VersionTLS12,
		excludeFlag: "-no-tls12",
		hasDTLS:     true,
		versionDTLS: VersionDTLS12,
	},
	{
		name:        "TLS13",
		version:     VersionTLS13,
		excludeFlag: "-no-tls13",
		hasQUIC:     true,
		hasDTLS:     true,
		versionDTLS: VersionDTLS13,
		versionWire: VersionTLS13,
	},
}

func allVersions(protocol protocol) []tlsVersion {
	if protocol == tls {
		return tlsVersions
	}

	var ret []tlsVersion
	for _, vers := range tlsVersions {
		if vers.supportsProtocol(protocol) {
			ret = append(ret, vers)
		}
	}
	return ret
}

type testCipherSuite struct {
	name string
	id   uint16
}

var testCipherSuites = []testCipherSuite{
	{"RSA_WITH_3DES_EDE_CBC_SHA", TLS_RSA_WITH_3DES_EDE_CBC_SHA},
	{"RSA_WITH_AES_128_GCM_SHA256", TLS_RSA_WITH_AES_128_GCM_SHA256},
	{"RSA_WITH_AES_128_CBC_SHA", TLS_RSA_WITH_AES_128_CBC_SHA},
	{"RSA_WITH_AES_256_GCM_SHA384", TLS_RSA_WITH_AES_256_GCM_SHA384},
	{"RSA_WITH_AES_256_CBC_SHA", TLS_RSA_WITH_AES_256_CBC_SHA},
	{"ECDHE_ECDSA_WITH_AES_128_GCM_SHA256", TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256},
	{"ECDHE_ECDSA_WITH_AES_128_CBC_SHA", TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA},
	{"ECDHE_ECDSA_WITH_AES_256_GCM_SHA384", TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384},
	{"ECDHE_ECDSA_WITH_AES_256_CBC_SHA", TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA},
	{"ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256", TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256},
	{"ECDHE_RSA_WITH_AES_128_GCM_SHA256", TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
	{"ECDHE_RSA_WITH_AES_128_CBC_SHA", TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA},
	{"ECDHE_RSA_WITH_AES_128_CBC_SHA256", TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256},
	{"ECDHE_RSA_WITH_AES_256_GCM_SHA384", TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384},
	{"ECDHE_RSA_WITH_AES_256_CBC_SHA", TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA},
	{"ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256", TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256},
	{"PSK_WITH_AES_128_CBC_SHA", TLS_PSK_WITH_AES_128_CBC_SHA},
	{"PSK_WITH_AES_256_CBC_SHA", TLS_PSK_WITH_AES_256_CBC_SHA},
	{"ECDHE_PSK_WITH_AES_128_CBC_SHA", TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA},
	{"ECDHE_PSK_WITH_AES_256_CBC_SHA", TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA},
	{"ECDHE_PSK_WITH_CHACHA20_POLY1305_SHA256", TLS_ECDHE_PSK_WITH_CHACHA20_POLY1305_SHA256},
	{"CHACHA20_POLY1305_SHA256", TLS_CHACHA20_POLY1305_SHA256},
	{"AES_128_GCM_SHA256", TLS_AES_128_GCM_SHA256},
	{"AES_256_GCM_SHA384", TLS_AES_256_GCM_SHA384},
}

func hasComponent(suiteName, component string) bool {
	return strings.Contains("_"+suiteName+"_", "_"+component+"_")
}

func isTLS12Only(suiteName string) bool {
	return hasComponent(suiteName, "GCM") ||
		hasComponent(suiteName, "SHA256") ||
		hasComponent(suiteName, "SHA384") ||
		hasComponent(suiteName, "POLY1305")
}

func isTLS13Suite(suiteName string) bool {
	return !hasComponent(suiteName, "WITH")
}

func bigFromHex(hex string) *big.Int {
	ret, ok := new(big.Int).SetString(hex, 16)
	if !ok {
		panic("failed to parse hex number 0x" + hex)
	}
	return ret
}

func convertToSplitHandshakeTests(tests []testCase) (splitHandshakeTests []testCase, err error) {
	var stdout bytes.Buffer
	var flags []string
	if len(*shimExtraFlags) > 0 {
		flags = strings.Split(*shimExtraFlags, ";")
	}
	flags = append(flags, "-is-handshaker-supported")
	shim := exec.Command(*shimPath, flags...)
	shim.Stdout = &stdout
	if err := shim.Run(); err != nil {
		return nil, err
	}

	switch strings.TrimSpace(string(stdout.Bytes())) {
	case "No":
		return
	case "Yes":
		break
	default:
		return nil, fmt.Errorf("unknown output from shim: %q", stdout.Bytes())
	}

	var allowHintMismatchPattern []string
	if len(*allowHintMismatch) > 0 {
		allowHintMismatchPattern = strings.Split(*allowHintMismatch, ";")
	}

NextTest:
	for _, test := range tests {
		if test.protocol != tls ||
			test.testType != serverTest ||
			len(test.shimCredentials) != 0 ||
			len(test.resumeShimCredentials) != 0 ||
			strings.Contains(test.name, "ECH-Server") ||
			test.skipSplitHandshake {
			continue
		}

		for _, flag := range test.flags {
			if flag == "-implicit-handshake" {
				continue NextTest
			}
		}

		shTest := test
		shTest.name += "-Split"
		shTest.flags = make([]string, len(test.flags), len(test.flags)+3)
		copy(shTest.flags, test.flags)
		shTest.flags = append(shTest.flags, "-handoff", "-handshaker-path", *handshakerPath)

		splitHandshakeTests = append(splitHandshakeTests, shTest)
	}

	for _, test := range tests {
		if test.protocol == dtls ||
			test.testType != serverTest ||
			test.skipHints {
			continue
		}

		var matched bool
		if len(allowHintMismatchPattern) > 0 {
			matched, err = match(allowHintMismatchPattern, nil, test.name)
			if err != nil {
				return nil, fmt.Errorf("error matching pattern: %s", err)
			}
		}

		shTest := test
		shTest.name += "-Hints"
		shTest.flags = make([]string, len(test.flags), len(test.flags)+3)
		copy(shTest.flags, test.flags)
		shTest.flags = append(shTest.flags, "-handshake-hints", "-handshaker-path", *handshakerPath)
		if matched {
			shTest.flags = append(shTest.flags, "-allow-hint-mismatch")
		}

		splitHandshakeTests = append(splitHandshakeTests, shTest)
	}

	return splitHandshakeTests, nil
}

func addBasicTests() {
	basicTests := []testCase{
		{
			name: "NoFallbackSCSV",
			config: Config{
				Bugs: ProtocolBugs{
					FailIfNotFallbackSCSV: true,
				},
			},
			shouldFail:         true,
			expectedLocalError: "no fallback SCSV found",
		},
		{
			name: "SendFallbackSCSV",
			config: Config{
				Bugs: ProtocolBugs{
					FailIfNotFallbackSCSV: true,
				},
			},
			flags: []string{"-fallback-scsv"},
		},
		{
			name: "ClientCertificateTypes",
			config: Config{
				MaxVersion: VersionTLS12,
				ClientAuth: RequestClientCert,
				ClientCertificateTypes: []byte{
					CertTypeDSSSign,
					CertTypeRSASign,
					CertTypeECDSASign,
				},
			},
			flags: []string{
				"-expect-certificate-types",
				base64FlagValue([]byte{
					CertTypeDSSSign,
					CertTypeRSASign,
					CertTypeECDSASign,
				}),
			},
		},
		{
			name: "CheckClientCertificateTypes",
			config: Config{
				MaxVersion:             VersionTLS12,
				ClientAuth:             RequestClientCert,
				ClientCertificateTypes: []byte{CertTypeECDSASign},
			},
			shimCertificate: &rsaCertificate,
			shouldFail:      true,
			expectedError:   ":UNKNOWN_CERTIFICATE_TYPE:",
		},
		{
			name: "UnauthenticatedECDH",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
				Bugs: ProtocolBugs{
					UnauthenticatedECDH: true,
				},
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_MESSAGE:",
		},
		{
			name: "SkipCertificateStatus",
			config: Config{
				MaxVersion:   VersionTLS12,
				Credential:   rsaCertificate.WithOCSP(testOCSPResponse),
				CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
				Bugs: ProtocolBugs{
					SkipCertificateStatus: true,
				},
			},
			flags: []string{
				"-enable-ocsp-stapling",
				// This test involves an optional message. Test the message callback
				// trace to ensure we do not miss or double-report any.
				"-expect-msg-callback",
				`write hs 1
read hs 2
read hs 11
read hs 12
read hs 14
write hs 16
write ccs
write hs 20
read hs 4
read ccs
read hs 20
read alert 1 0
`,
			},
		},
		{
			protocol: dtls,
			name:     "SkipCertificateStatus-DTLS",
			config: Config{
				MaxVersion:   VersionTLS12,
				Credential:   rsaCertificate.WithOCSP(testOCSPResponse),
				CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
				Bugs: ProtocolBugs{
					SkipCertificateStatus: true,
				},
			},
			flags: []string{
				"-enable-ocsp-stapling",
				// This test involves an optional message. Test the message callback
				// trace to ensure we do not miss or double-report any.
				"-expect-msg-callback",
				`write hs 1
read hs 3
write hs 1
read hs 2
read hs 11
read hs 12
read hs 14
write hs 16
write ccs
write hs 20
read hs 4
read ccs
read hs 20
read alert 1 0
`,
			},
		},
		{
			name: "SkipServerKeyExchange",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
				Bugs: ProtocolBugs{
					SkipServerKeyExchange: true,
				},
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_MESSAGE:",
		},
		{
			testType: serverTest,
			name:     "ServerSkipCertificateVerify",
			config: Config{
				MaxVersion: VersionTLS12,
				Credential: &rsaCertificate,
				Bugs: ProtocolBugs{
					SkipCertificateVerify: true,
				},
			},
			expectations: connectionExpectations{
				peerCertificate: &rsaCertificate,
			},
			flags: []string{
				"-require-any-client-certificate",
			},
			shouldFail:         true,
			expectedError:      ":UNEXPECTED_RECORD:",
			expectedLocalError: "remote error: unexpected message",
		},
		{
			testType: serverTest,
			name:     "Alert",
			config: Config{
				Bugs: ProtocolBugs{
					SendSpuriousAlert: alertRecordOverflow,
				},
			},
			shouldFail:    true,
			expectedError: ":TLSV1_ALERT_RECORD_OVERFLOW:",
		},
		{
			protocol: dtls,
			testType: serverTest,
			name:     "Alert-DTLS",
			config: Config{
				Bugs: ProtocolBugs{
					SendSpuriousAlert: alertRecordOverflow,
				},
			},
			shouldFail:    true,
			expectedError: ":TLSV1_ALERT_RECORD_OVERFLOW:",
		},
		{
			testType: serverTest,
			name:     "FragmentAlert",
			config: Config{
				Bugs: ProtocolBugs{
					FragmentAlert:     true,
					SendSpuriousAlert: alertRecordOverflow,
				},
			},
			shouldFail:    true,
			expectedError: ":BAD_ALERT:",
		},
		{
			protocol: dtls,
			testType: serverTest,
			name:     "FragmentAlert-DTLS",
			config: Config{
				Bugs: ProtocolBugs{
					FragmentAlert:     true,
					SendSpuriousAlert: alertRecordOverflow,
				},
			},
			shouldFail:    true,
			expectedError: ":BAD_ALERT:",
		},
		{
			testType: serverTest,
			name:     "DoubleAlert",
			config: Config{
				Bugs: ProtocolBugs{
					DoubleAlert:       true,
					SendSpuriousAlert: alertRecordOverflow,
				},
			},
			shouldFail:    true,
			expectedError: ":BAD_ALERT:",
		},
		{
			protocol: dtls,
			testType: serverTest,
			name:     "DoubleAlert-DTLS",
			config: Config{
				Bugs: ProtocolBugs{
					DoubleAlert:       true,
					SendSpuriousAlert: alertRecordOverflow,
				},
			},
			shouldFail:    true,
			expectedError: ":BAD_ALERT:",
		},
		{
			name: "SkipNewSessionTicket",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					SkipNewSessionTicket: true,
				},
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_RECORD:",
		},
		{
			testType: serverTest,
			name:     "FallbackSCSV",
			config: Config{
				MaxVersion: VersionTLS11,
				Bugs: ProtocolBugs{
					SendFallbackSCSV: true,
				},
			},
			shouldFail:         true,
			expectedError:      ":INAPPROPRIATE_FALLBACK:",
			expectedLocalError: "remote error: inappropriate fallback",
		},
		{
			testType: serverTest,
			name:     "FallbackSCSV-VersionMatch-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					SendFallbackSCSV: true,
				},
			},
		},
		{
			testType: serverTest,
			name:     "FallbackSCSV-VersionMatch-TLS12",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					SendFallbackSCSV: true,
				},
			},
			flags: []string{"-max-version", strconv.Itoa(VersionTLS12)},
		},
		// Regression test for CVE-2014-3511. Even when the ClientHello is
		// maximally fragmented, version negotiation works correctly.
		{
			testType: serverTest,
			name:     "FragmentedClientVersion",
			config: Config{
				Bugs: ProtocolBugs{
					MaxHandshakeRecordLength: 1,
				},
			},
			expectations: connectionExpectations{
				version: VersionTLS13,
			},
		},
		{
			testType:      serverTest,
			name:          "HttpGET",
			sendPrefix:    "GET / HTTP/1.0\n",
			shouldFail:    true,
			expectedError: ":HTTP_REQUEST:",
		},
		{
			testType:      serverTest,
			name:          "HttpPOST",
			sendPrefix:    "POST / HTTP/1.0\n",
			shouldFail:    true,
			expectedError: ":HTTP_REQUEST:",
		},
		{
			testType:      serverTest,
			name:          "HttpHEAD",
			sendPrefix:    "HEAD / HTTP/1.0\n",
			shouldFail:    true,
			expectedError: ":HTTP_REQUEST:",
		},
		{
			testType:      serverTest,
			name:          "HttpPUT",
			sendPrefix:    "PUT / HTTP/1.0\n",
			shouldFail:    true,
			expectedError: ":HTTP_REQUEST:",
		},
		{
			testType:      serverTest,
			name:          "HttpCONNECT",
			sendPrefix:    "CONNECT www.google.com:443 HTTP/1.0\n",
			shouldFail:    true,
			expectedError: ":HTTPS_PROXY_REQUEST:",
		},
		{
			testType:      serverTest,
			name:          "Garbage",
			sendPrefix:    "blah",
			shouldFail:    true,
			expectedError: ":WRONG_VERSION_NUMBER:",
		},
		{
			name: "RSAEphemeralKey",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_RSA_WITH_AES_128_CBC_SHA},
				Bugs: ProtocolBugs{
					RSAEphemeralKey: true,
				},
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_MESSAGE:",
		},
		{
			name:          "DisableEverything",
			flags:         []string{"-no-tls13", "-no-tls12", "-no-tls11", "-no-tls1"},
			shouldFail:    true,
			expectedError: ":NO_SUPPORTED_VERSIONS_ENABLED:",
		},
		{
			protocol:      dtls,
			name:          "DisableEverything-DTLS",
			flags:         []string{"-no-tls13", "-no-tls12", "-no-tls1"},
			shouldFail:    true,
			expectedError: ":NO_SUPPORTED_VERSIONS_ENABLED:",
		},
		{
			protocol: dtls,
			testType: serverTest,
			name:     "MTU-DTLS12-AEAD",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
				Bugs: ProtocolBugs{
					MaxPacketLength: 256,
				},
			},
			flags: []string{"-mtu", "256"},
		},
		{
			protocol: dtls,
			testType: serverTest,
			name:     "MTU-DTLS12-AES-CBC",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256},
				Bugs: ProtocolBugs{
					MaxPacketLength: 256,
				},
			},
			flags: []string{"-mtu", "256"},
		},
		{
			protocol: dtls,
			testType: serverTest,
			name:     "MTU-DTLS12-3DES-CBC",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_RSA_WITH_3DES_EDE_CBC_SHA},
				Bugs: ProtocolBugs{
					MaxPacketLength: 256,
				},
			},
			flags: []string{"-mtu", "256", "-cipher", "TLS_RSA_WITH_3DES_EDE_CBC_SHA"},
		},
		{
			protocol: dtls,
			testType: serverTest,
			name:     "MTU-DTLS13",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					MaxPacketLength: 256,
				},
			},
			flags: []string{"-mtu", "256"},
		},
		{
			name: "EmptyCertificateList",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					EmptyCertificateList: true,
				},
			},
			shouldFail:    true,
			expectedError: ":DECODE_ERROR:",
		},
		{
			name: "EmptyCertificateList-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					EmptyCertificateList: true,
				},
			},
			shouldFail:    true,
			expectedError: ":PEER_DID_NOT_RETURN_A_CERTIFICATE:",
		},
		{
			name:             "TLSFatalBadPackets",
			damageFirstWrite: true,
			shouldFail:       true,
			expectedError:    ":DECRYPTION_FAILED_OR_BAD_RECORD_MAC:",
		},
		{
			protocol:         dtls,
			name:             "DTLSIgnoreBadPackets",
			damageFirstWrite: true,
		},
		{
			protocol:         dtls,
			name:             "DTLSIgnoreBadPackets-Async",
			damageFirstWrite: true,
			flags:            []string{"-async"},
		},
		{
			name: "AppDataBeforeHandshake",
			config: Config{
				Bugs: ProtocolBugs{
					AppDataBeforeHandshake: []byte("TEST MESSAGE"),
				},
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_RECORD:",
		},
		{
			name: "AppDataBeforeHandshake-Empty",
			config: Config{
				Bugs: ProtocolBugs{
					AppDataBeforeHandshake: []byte{},
				},
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_RECORD:",
		},
		{
			protocol: dtls,
			name:     "AppDataBeforeHandshake-DTLS",
			config: Config{
				Bugs: ProtocolBugs{
					AppDataBeforeHandshake: []byte("TEST MESSAGE"),
				},
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_RECORD:",
		},
		{
			protocol: dtls,
			name:     "AppDataBeforeHandshake-DTLS-Empty",
			config: Config{
				Bugs: ProtocolBugs{
					AppDataBeforeHandshake: []byte{},
				},
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_RECORD:",
		},
		{
			name: "AppDataBeforeTLS13KeyChange",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					AppDataBeforeTLS13KeyChange: []byte("TEST MESSAGE"),
				},
			},
			// The shim should fail to decrypt this record.
			shouldFail:         true,
			expectedError:      ":BAD_DECRYPT:",
			expectedLocalError: "remote error: bad record MAC",
		},
		{
			name: "AppDataBeforeTLS13KeyChange-Empty",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					AppDataBeforeTLS13KeyChange: []byte{},
				},
			},
			// The shim should fail to decrypt this record.
			shouldFail:         true,
			expectedError:      ":BAD_DECRYPT:",
			expectedLocalError: "remote error: bad record MAC",
		},
		{
			protocol: dtls,
			name:     "AppDataBeforeTLS13KeyChange-DTLS",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					AppDataBeforeTLS13KeyChange: []byte("TEST MESSAGE"),
				},
			},
			// The shim will decrypt the record, because it has not
			// yet applied the key change, but it should know to
			// reject the record.
			shouldFail:         true,
			expectedError:      ":UNEXPECTED_RECORD:",
			expectedLocalError: "remote error: unexpected message",
		},
		{
			protocol: dtls,
			name:     "AppDataBeforeTLS13KeyChange-DTLS-Empty",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					AppDataBeforeTLS13KeyChange: []byte{},
				},
			},
			// The shim will decrypt the record, because it has not
			// yet applied the key change, but it should know to
			// reject the record.
			shouldFail:         true,
			expectedError:      ":UNEXPECTED_RECORD:",
			expectedLocalError: "remote error: unexpected message",
		},
		{
			name: "UnencryptedEncryptedExtensions",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					UnencryptedEncryptedExtensions: true,
				},
			},
			// The shim should fail to decrypt this record.
			shouldFail:         true,
			expectedError:      ":DECRYPTION_FAILED_OR_BAD_RECORD_MAC:",
			expectedLocalError: "remote error: bad record MAC",
		},
		{
			protocol: dtls,
			name:     "UnencryptedEncryptedExtensions-DTLS",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					UnencryptedEncryptedExtensions: true,
				},
			},
			// The shim will decrypt the record, because it has not
			// yet applied the key change, but it should know to
			// reject new handshake data on the previous epoch.
			shouldFail:         true,
			expectedError:      ":EXCESS_HANDSHAKE_DATA:",
			expectedLocalError: "remote error: unexpected message",
		},
		{
			name: "AppDataAfterChangeCipherSpec",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					AppDataAfterChangeCipherSpec: []byte("TEST MESSAGE"),
				},
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_RECORD:",
		},
		{
			name: "AppDataAfterChangeCipherSpec-Empty",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					AppDataAfterChangeCipherSpec: []byte{},
				},
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_RECORD:",
		},
		{
			protocol: dtls,
			name:     "AppDataAfterChangeCipherSpec-DTLS",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					AppDataAfterChangeCipherSpec: []byte("TEST MESSAGE"),
				},
			},
			// BoringSSL's DTLS implementation will drop the out-of-order
			// application data.
		},
		{
			protocol: dtls,
			name:     "AppDataAfterChangeCipherSpec-DTLS-Empty",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					AppDataAfterChangeCipherSpec: []byte{},
				},
			},
			// BoringSSL's DTLS implementation will drop the out-of-order
			// application data.
		},
		{
			name: "AlertAfterChangeCipherSpec",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					AlertAfterChangeCipherSpec: alertRecordOverflow,
				},
			},
			shouldFail:    true,
			expectedError: ":TLSV1_ALERT_RECORD_OVERFLOW:",
		},
		{
			protocol: dtls,
			name:     "AlertAfterChangeCipherSpec-DTLS",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					AlertAfterChangeCipherSpec: alertRecordOverflow,
				},
			},
			shouldFail:    true,
			expectedError: ":TLSV1_ALERT_RECORD_OVERFLOW:",
		},
		{
			name: "SendInvalidRecordType",
			config: Config{
				Bugs: ProtocolBugs{
					SendInvalidRecordType: true,
				},
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_RECORD:",
		},
		{
			protocol: dtls,
			name:     "SendInvalidRecordType-DTLS",
			config: Config{
				Bugs: ProtocolBugs{
					SendInvalidRecordType: true,
				},
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_RECORD:",
		},
		{
			name: "FalseStart-SkipServerSecondLeg",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
				NextProtos:   []string{"foo"},
				Bugs: ProtocolBugs{
					SkipNewSessionTicket: true,
					SkipChangeCipherSpec: true,
					SkipFinished:         true,
					ExpectFalseStart:     true,
				},
			},
			flags: []string{
				"-false-start",
				"-handshake-never-done",
				"-advertise-alpn", "\x03foo",
				"-expect-alpn", "foo",
			},
			shimWritesFirst: true,
			shouldFail:      true,
			expectedError:   ":UNEXPECTED_RECORD:",
		},
		{
			name: "FalseStart-SkipServerSecondLeg-Implicit",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
				NextProtos:   []string{"foo"},
				Bugs: ProtocolBugs{
					SkipNewSessionTicket: true,
					SkipChangeCipherSpec: true,
					SkipFinished:         true,
				},
			},
			flags: []string{
				"-implicit-handshake",
				"-false-start",
				"-handshake-never-done",
				"-advertise-alpn", "\x03foo",
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_RECORD:",
		},
		{
			testType:           serverTest,
			name:               "FailEarlyCallback",
			flags:              []string{"-fail-early-callback"},
			shouldFail:         true,
			expectedError:      ":CONNECTION_REJECTED:",
			expectedLocalError: "remote error: handshake failure",
		},
		{
			name: "FailCertCallback-Client-TLS12",
			config: Config{
				MaxVersion: VersionTLS12,
				ClientAuth: RequestClientCert,
			},
			flags:              []string{"-fail-cert-callback"},
			shouldFail:         true,
			expectedError:      ":CERT_CB_ERROR:",
			expectedLocalError: "remote error: internal error",
		},
		{
			testType: serverTest,
			name:     "FailCertCallback-Server-TLS12",
			config: Config{
				MaxVersion: VersionTLS12,
			},
			flags:              []string{"-fail-cert-callback"},
			shouldFail:         true,
			expectedError:      ":CERT_CB_ERROR:",
			expectedLocalError: "remote error: internal error",
		},
		{
			name: "FailCertCallback-Client-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
				ClientAuth: RequestClientCert,
			},
			flags:              []string{"-fail-cert-callback"},
			shouldFail:         true,
			expectedError:      ":CERT_CB_ERROR:",
			expectedLocalError: "remote error: internal error",
		},
		{
			testType: serverTest,
			name:     "FailCertCallback-Server-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
			},
			flags:              []string{"-fail-cert-callback"},
			shouldFail:         true,
			expectedError:      ":CERT_CB_ERROR:",
			expectedLocalError: "remote error: internal error",
		},
		{
			protocol: dtls,
			name:     "FragmentMessageTypeMismatch-DTLS",
			config: Config{
				Bugs: ProtocolBugs{
					WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
						f1 := next[0].Fragment(0, 1)
						f2 := next[0].Fragment(1, 1)
						f2.Type++
						c.WriteFragments([]DTLSFragment{f1, f2})
					},
				},
			},
			shouldFail:    true,
			expectedError: ":FRAGMENT_MISMATCH:",
		},
		{
			protocol: dtls,
			name:     "FragmentMessageLengthMismatch-DTLS",
			config: Config{
				Bugs: ProtocolBugs{
					WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
						f1 := next[0].Fragment(0, 1)
						f2 := next[0].Fragment(1, 1)
						f2.TotalLength++
						c.WriteFragments([]DTLSFragment{f1, f2})
					},
				},
			},
			shouldFail:    true,
			expectedError: ":FRAGMENT_MISMATCH:",
		},
		{
			protocol: dtls,
			name:     "SplitFragments-Header-DTLS",
			config: Config{
				Bugs: ProtocolBugs{
					SplitFragments: 2,
				},
			},
			shouldFail:    true,
			expectedError: ":BAD_HANDSHAKE_RECORD:",
		},
		{
			protocol: dtls,
			name:     "SplitFragments-Boundary-DTLS",
			config: Config{
				Bugs: ProtocolBugs{
					SplitFragments: dtlsMaxRecordHeaderLen,
				},
			},
			shouldFail:    true,
			expectedError: ":BAD_HANDSHAKE_RECORD:",
		},
		{
			protocol: dtls,
			name:     "SplitFragments-Body-DTLS",
			config: Config{
				Bugs: ProtocolBugs{
					SplitFragments: dtlsMaxRecordHeaderLen + 1,
				},
			},
			shouldFail:    true,
			expectedError: ":BAD_HANDSHAKE_RECORD:",
		},
		{
			protocol: dtls,
			name:     "SendEmptyFragments-DTLS",
			config: Config{
				Bugs: ProtocolBugs{
					SendEmptyFragments: true,
				},
			},
		},
		{
			testType: serverTest,
			protocol: dtls,
			name:     "SendEmptyFragments-Padded-DTLS",
			config: Config{
				Bugs: ProtocolBugs{
					// Test empty fragments for a message with a
					// nice power-of-two length.
					PadClientHello:     64,
					SendEmptyFragments: true,
				},
			},
		},
		{
			name: "BadFinished-Client",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					BadFinished: true,
				},
			},
			shouldFail:    true,
			expectedError: ":DIGEST_CHECK_FAILED:",
		},
		{
			name: "BadFinished-Client-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					BadFinished: true,
				},
			},
			shouldFail:    true,
			expectedError: ":DIGEST_CHECK_FAILED:",
		},
		{
			testType: serverTest,
			name:     "BadFinished-Server",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					BadFinished: true,
				},
			},
			shouldFail:    true,
			expectedError: ":DIGEST_CHECK_FAILED:",
		},
		{
			testType: serverTest,
			name:     "BadFinished-Server-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					BadFinished: true,
				},
			},
			shouldFail:    true,
			expectedError: ":DIGEST_CHECK_FAILED:",
		},
		{
			name: "FalseStart-BadFinished",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
				NextProtos:   []string{"foo"},
				Bugs: ProtocolBugs{
					BadFinished:      true,
					ExpectFalseStart: true,
				},
			},
			flags: []string{
				"-false-start",
				"-handshake-never-done",
				"-advertise-alpn", "\x03foo",
				"-expect-alpn", "foo",
			},
			shimWritesFirst: true,
			shouldFail:      true,
			expectedError:   ":DIGEST_CHECK_FAILED:",
		},
		{
			name: "NoFalseStart-NoALPN",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
				Bugs: ProtocolBugs{
					ExpectFalseStart:          true,
					AlertBeforeFalseStartTest: alertAccessDenied,
				},
			},
			flags: []string{
				"-false-start",
			},
			shimWritesFirst:    true,
			shouldFail:         true,
			expectedError:      ":TLSV1_ALERT_ACCESS_DENIED:",
			expectedLocalError: "tls: peer did not false start: EOF",
		},
		{
			name: "FalseStart-NoALPNAllowed",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
				Bugs: ProtocolBugs{
					ExpectFalseStart: true,
				},
			},
			flags: []string{
				"-false-start",
				"-allow-false-start-without-alpn",
			},
			shimWritesFirst: true,
		},
		{
			name: "NoFalseStart-NoAEAD",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA},
				NextProtos:   []string{"foo"},
				Bugs: ProtocolBugs{
					ExpectFalseStart:          true,
					AlertBeforeFalseStartTest: alertAccessDenied,
				},
			},
			flags: []string{
				"-false-start",
				"-advertise-alpn", "\x03foo",
			},
			shimWritesFirst:    true,
			shouldFail:         true,
			expectedError:      ":TLSV1_ALERT_ACCESS_DENIED:",
			expectedLocalError: "tls: peer did not false start: EOF",
		},
		{
			name: "NoFalseStart-RSA",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_RSA_WITH_AES_128_GCM_SHA256},
				NextProtos:   []string{"foo"},
				Bugs: ProtocolBugs{
					ExpectFalseStart:          true,
					AlertBeforeFalseStartTest: alertAccessDenied,
				},
			},
			flags: []string{
				"-false-start",
				"-advertise-alpn", "\x03foo",
			},
			shimWritesFirst:    true,
			shouldFail:         true,
			expectedError:      ":TLSV1_ALERT_ACCESS_DENIED:",
			expectedLocalError: "tls: peer did not false start: EOF",
		},
		{
			protocol: dtls,
			name:     "SendSplitAlert-Sync",
			config: Config{
				Bugs: ProtocolBugs{
					SendSplitAlert: true,
				},
			},
		},
		{
			protocol: dtls,
			name:     "SendSplitAlert-Async",
			config: Config{
				Bugs: ProtocolBugs{
					SendSplitAlert: true,
				},
			},
			flags: []string{"-async"},
		},
		{
			name:             "SendEmptyRecords-Pass",
			sendEmptyRecords: 32,
		},
		{
			name:             "SendEmptyRecords",
			sendEmptyRecords: 33,
			shouldFail:       true,
			expectedError:    ":TOO_MANY_EMPTY_FRAGMENTS:",
		},
		{
			name:             "SendEmptyRecords-Async",
			sendEmptyRecords: 33,
			flags:            []string{"-async"},
			shouldFail:       true,
			expectedError:    ":TOO_MANY_EMPTY_FRAGMENTS:",
		},
		{
			name: "SendWarningAlerts-Pass",
			config: Config{
				MaxVersion: VersionTLS12,
			},
			sendWarningAlerts: 4,
		},
		{
			protocol: dtls,
			name:     "SendWarningAlerts-DTLS-Pass",
			config: Config{
				MaxVersion: VersionTLS12,
			},
			sendWarningAlerts: 4,
		},
		{
			name: "SendWarningAlerts-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
			},
			sendWarningAlerts:  4,
			shouldFail:         true,
			expectedError:      ":BAD_ALERT:",
			expectedLocalError: "remote error: error decoding message",
		},
		// Although TLS 1.3 intended to remove warning alerts, it left in
		// user_canceled. JDK11 misuses this alert as a post-handshake
		// full-duplex signal. As a workaround, skip user_canceled as in
		// TLS 1.2, which is consistent with NSS and OpenSSL.
		{
			name: "SendUserCanceledAlerts-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
			},
			sendUserCanceledAlerts: 4,
		},
		{
			name: "SendUserCanceledAlerts-TooMany-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
			},
			sendUserCanceledAlerts: 5,
			shouldFail:             true,
			expectedError:          ":TOO_MANY_WARNING_ALERTS:",
		},
		{
			name: "SendWarningAlerts-TooMany",
			config: Config{
				MaxVersion: VersionTLS12,
			},
			sendWarningAlerts: 5,
			shouldFail:        true,
			expectedError:     ":TOO_MANY_WARNING_ALERTS:",
		},
		{
			name: "SendWarningAlerts-TooMany-Async",
			config: Config{
				MaxVersion: VersionTLS12,
			},
			sendWarningAlerts: 5,
			flags:             []string{"-async"},
			shouldFail:        true,
			expectedError:     ":TOO_MANY_WARNING_ALERTS:",
		},
		{
			name:               "SendBogusAlertType",
			sendBogusAlertType: true,
			shouldFail:         true,
			expectedError:      ":UNKNOWN_ALERT_TYPE:",
			expectedLocalError: "remote error: illegal parameter",
		},
		{
			protocol:           dtls,
			name:               "SendBogusAlertType-DTLS",
			sendBogusAlertType: true,
			shouldFail:         true,
			expectedError:      ":UNKNOWN_ALERT_TYPE:",
			expectedLocalError: "remote error: illegal parameter",
		},
		{
			name: "TooManyKeyUpdates",
			config: Config{
				MaxVersion: VersionTLS13,
			},
			sendKeyUpdates:   33,
			keyUpdateRequest: keyUpdateNotRequested,
			shouldFail:       true,
			expectedError:    ":TOO_MANY_KEY_UPDATES:",
		},
		{
			name: "EmptySessionID",
			config: Config{
				MaxVersion:             VersionTLS12,
				SessionTicketsDisabled: true,
			},
			noSessionCache: true,
			flags:          []string{"-expect-no-session"},
		},
		{
			name: "Unclean-Shutdown",
			config: Config{
				Bugs: ProtocolBugs{
					NoCloseNotify:     true,
					ExpectCloseNotify: true,
				},
			},
			shimShutsDown: true,
			flags:         []string{"-check-close-notify"},
			shouldFail:    true,
			expectedError: "Unexpected SSL_shutdown result: -1 != 1",
		},
		{
			name: "Unclean-Shutdown-Ignored",
			config: Config{
				Bugs: ProtocolBugs{
					NoCloseNotify: true,
				},
			},
			shimShutsDown: true,
		},
		{
			name: "Unclean-Shutdown-Alert",
			config: Config{
				Bugs: ProtocolBugs{
					SendAlertOnShutdown: alertDecompressionFailure,
					ExpectCloseNotify:   true,
				},
			},
			shimShutsDown: true,
			flags:         []string{"-check-close-notify"},
			shouldFail:    true,
			expectedError: ":SSLV3_ALERT_DECOMPRESSION_FAILURE:",
		},
		{
			name: "LargePlaintext",
			config: Config{
				Bugs: ProtocolBugs{
					SendLargeRecords: true,
				},
			},
			messageLen:         maxPlaintext + 1,
			shouldFail:         true,
			expectedError:      ":DATA_LENGTH_TOO_LONG:",
			expectedLocalError: "remote error: record overflow",
		},
		{
			protocol: dtls,
			name:     "LargePlaintext-DTLS",
			config: Config{
				Bugs: ProtocolBugs{
					SendLargeRecords: true,
				},
			},
			messageLen:         maxPlaintext + 1,
			shouldFail:         true,
			expectedError:      ":DATA_LENGTH_TOO_LONG:",
			expectedLocalError: "remote error: record overflow",
		},
		{
			name: "LargePlaintext-TLS13-Padded-8192-8192",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					RecordPadding:    8192,
					SendLargeRecords: true,
				},
			},
			messageLen: 8192,
		},
		{
			name: "LargePlaintext-TLS13-Padded-8193-8192",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					RecordPadding:    8193,
					SendLargeRecords: true,
				},
			},
			messageLen:         8192,
			shouldFail:         true,
			expectedError:      ":DATA_LENGTH_TOO_LONG:",
			expectedLocalError: "remote error: record overflow",
		},
		{
			name: "LargePlaintext-TLS13-Padded-16383-1",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					RecordPadding:    1,
					SendLargeRecords: true,
				},
			},
			messageLen: 16383,
		},
		{
			name: "LargePlaintext-TLS13-Padded-16384-1",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					RecordPadding:    1,
					SendLargeRecords: true,
				},
			},
			messageLen:         16384,
			shouldFail:         true,
			expectedError:      ":DATA_LENGTH_TOO_LONG:",
			expectedLocalError: "remote error: record overflow",
		},
		{
			name: "LargeCiphertext",
			config: Config{
				Bugs: ProtocolBugs{
					SendLargeRecords: true,
				},
			},
			messageLen:    maxPlaintext * 2,
			shouldFail:    true,
			expectedError: ":ENCRYPTED_LENGTH_TOO_LONG:",
		},
		{
			protocol: dtls,
			name:     "LargeCiphertext-DTLS",
			config: Config{
				Bugs: ProtocolBugs{
					SendLargeRecords: true,
				},
			},
			messageLen: maxPlaintext * 2,
			// Unlike the other four cases, DTLS drops records which
			// are invalid before authentication, so the connection
			// does not fail.
			expectMessageDropped: true,
		},
		{
			name:        "BadHelloRequest-1",
			renegotiate: 1,
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					BadHelloRequest: []byte{typeHelloRequest, 0, 0, 1, 1},
				},
			},
			flags: []string{
				"-renegotiate-freely",
				"-expect-total-renegotiations", "1",
			},
			shouldFail:    true,
			expectedError: ":BAD_HELLO_REQUEST:",
		},
		{
			name:        "BadHelloRequest-2",
			renegotiate: 1,
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					BadHelloRequest: []byte{typeServerKeyExchange, 0, 0, 0},
				},
			},
			flags: []string{
				"-renegotiate-freely",
				"-expect-total-renegotiations", "1",
			},
			shouldFail:    true,
			expectedError: ":BAD_HELLO_REQUEST:",
		},
		{
			testType: serverTest,
			name:     "SupportTicketsWithSessionID",
			config: Config{
				MaxVersion:             VersionTLS12,
				SessionTicketsDisabled: true,
			},
			resumeConfig: &Config{
				MaxVersion: VersionTLS12,
			},
			resumeSession: true,
		},
		{
			protocol: dtls,
			name:     "DTLS12-SendExtraFinished",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					SendExtraFinished: true,
				},
			},
			shouldFail:         true,
			expectedError:      ":UNEXPECTED_RECORD:",
			expectedLocalError: "remote error: unexpected message",
		},
		{
			protocol: dtls,
			name:     "DTLS12-SendExtraFinished-Reordered",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					MaxHandshakeRecordLength:  2,
					ReorderHandshakeFragments: true,
					SendExtraFinished:         true,
				},
			},
			shouldFail:         true,
			expectedError:      ":EXCESS_HANDSHAKE_DATA:",
			expectedLocalError: "remote error: unexpected message",
		},
		{
			protocol: dtls,
			name:     "DTLS12-SendExtraFinished-Packed",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					SendExtraFinished:      true,
					PackHandshakeFragments: 1000,
				},
			},
			shouldFail:         true,
			expectedError:      ":EXCESS_HANDSHAKE_DATA:",
			expectedLocalError: "remote error: unexpected message",
		},
		{
			protocol: dtls,
			name:     "DTLS13-SendExtraFinished",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					SendExtraFinished: true,
				},
			},
			shouldFail:         true,
			expectedError:      ":EXCESS_HANDSHAKE_DATA:",
			expectedLocalError: "remote error: unexpected message",
		},
		{
			protocol: dtls,
			name:     "DTLS13-SendExtraFinished-Reordered",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					MaxHandshakeRecordLength:  2,
					ReorderHandshakeFragments: true,
					SendExtraFinished:         true,
				},
			},
			shouldFail:         true,
			expectedError:      ":EXCESS_HANDSHAKE_DATA:",
			expectedLocalError: "remote error: unexpected message",
		},
		{
			protocol: dtls,
			name:     "DTLS13-SendExtraFinished-Packed",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					SendExtraFinished:      true,
					PackHandshakeFragments: 1000,
				},
			},
			shouldFail:         true,
			expectedError:      ":EXCESS_HANDSHAKE_DATA:",
			expectedLocalError: "remote error: unexpected message",
		},
		{
			protocol: dtls,
			testType: serverTest,
			name:     "DTLS13-SendExtraFinished-AfterAppData",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					SkipImplicitACKRead: true,
					WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
						if next[len(next)-1].Type != typeFinished {
							c.WriteFlight(next)
							return
						}

						// Complete the handshake.
						c.WriteFlight(next)
						c.ReadACK(c.InEpoch())

						// Send some application data. The shim is now on epoch 3.
						msg := []byte("hello")
						c.WriteAppData(c.OutEpoch(), msg)
						c.ReadAppData(c.InEpoch(), expectedReply(msg))

						// The shim is still accepting data from epoch 2, so it can
						// ACK a retransmit if needed, but it should not accept new
						// messages at epoch three.
						extraFinished := next[len(next)-1]
						extraFinished.Sequence++
						c.WriteFlight([]DTLSMessage{extraFinished})
					},
				},
			},
			shouldFail:         true,
			expectedError:      ":EXCESS_HANDSHAKE_DATA:",
			expectedLocalError: "remote error: unexpected message",
			// Disable tickets on the shim to avoid NewSessionTicket
			// interfering with the test callback.
			flags: []string{"-no-ticket"},
		},
		{
			testType: serverTest,
			name:     "V2ClientHello-EmptyRecordPrefix",
			config: Config{
				// Choose a cipher suite that does not involve
				// elliptic curves, so no extensions are
				// involved.
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_RSA_WITH_AES_128_CBC_SHA},
				Bugs: ProtocolBugs{
					SendV2ClientHello: true,
				},
			},
			sendPrefix: string([]byte{
				byte(recordTypeHandshake),
				3, 1, // version
				0, 0, // length
			}),
			// A no-op empty record may not be sent before V2ClientHello.
			shouldFail:    true,
			expectedError: ":WRONG_VERSION_NUMBER:",
		},
		{
			testType: serverTest,
			name:     "V2ClientHello-WarningAlertPrefix",
			config: Config{
				// Choose a cipher suite that does not involve
				// elliptic curves, so no extensions are
				// involved.
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_RSA_WITH_AES_128_CBC_SHA},
				Bugs: ProtocolBugs{
					SendV2ClientHello: true,
				},
			},
			sendPrefix: string([]byte{
				byte(recordTypeAlert),
				3, 1, // version
				0, 2, // length
				alertLevelWarning, byte(alertDecompressionFailure),
			}),
			// A no-op warning alert may not be sent before V2ClientHello.
			shouldFail:    true,
			expectedError: ":WRONG_VERSION_NUMBER:",
		},
		{
			name: "SendSNIWarningAlert",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					SendSNIWarningAlert: true,
				},
			},
		},
		{
			testType: serverTest,
			name:     "ExtraCompressionMethods-TLS12",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					SendCompressionMethods: []byte{1, 2, 3, compressionNone, 4, 5, 6},
				},
			},
		},
		{
			testType: serverTest,
			name:     "ExtraCompressionMethods-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					SendCompressionMethods: []byte{1, 2, 3, compressionNone, 4, 5, 6},
				},
			},
			shouldFail:         true,
			expectedError:      ":INVALID_COMPRESSION_LIST:",
			expectedLocalError: "remote error: illegal parameter",
		},
		{
			testType: serverTest,
			name:     "NoNullCompression-TLS12",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					SendCompressionMethods: []byte{1, 2, 3, 4, 5, 6},
				},
			},
			shouldFail:         true,
			expectedError:      ":INVALID_COMPRESSION_LIST:",
			expectedLocalError: "remote error: illegal parameter",
		},
		{
			testType: serverTest,
			name:     "NoNullCompression-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					SendCompressionMethods: []byte{1, 2, 3, 4, 5, 6},
				},
			},
			shouldFail:         true,
			expectedError:      ":INVALID_COMPRESSION_LIST:",
			expectedLocalError: "remote error: illegal parameter",
		},
		// Test that the client rejects invalid compression methods
		// from the server.
		{
			testType: clientTest,
			name:     "InvalidCompressionMethod",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					SendCompressionMethod: 1,
				},
			},
			shouldFail:         true,
			expectedError:      ":UNSUPPORTED_COMPRESSION_ALGORITHM:",
			expectedLocalError: "remote error: illegal parameter",
		},
		{
			testType: clientTest,
			name:     "TLS13-InvalidCompressionMethod",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					SendCompressionMethod: 1,
				},
			},
			shouldFail:    true,
			expectedError: ":DECODE_ERROR:",
		},
		{
			testType: clientTest,
			name:     "TLS13-HRR-InvalidCompressionMethod",
			config: Config{
				MaxVersion:       VersionTLS13,
				CurvePreferences: []CurveID{CurveP384},
				Bugs: ProtocolBugs{
					SendCompressionMethod: 1,
				},
			},
			shouldFail:         true,
			expectedError:      ":DECODE_ERROR:",
			expectedLocalError: "remote error: error decoding message",
		},
		{
			name: "GREASE-Client-TLS12",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					ExpectGREASE: true,
				},
			},
			flags: []string{"-enable-grease"},
		},
		{
			name: "GREASE-Client-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					ExpectGREASE: true,
				},
			},
			flags: []string{"-enable-grease"},
		},
		{
			testType: serverTest,
			name:     "GREASE-Server-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					// TLS 1.3 servers are expected to
					// always enable GREASE. TLS 1.3 is new,
					// so there is no existing ecosystem to
					// worry about.
					ExpectGREASE: true,
				},
			},
		},
		{
			// Test the TLS 1.2 server so there is a large
			// unencrypted certificate as well as application data.
			testType: serverTest,
			name:     "MaxSendFragment-TLS12",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					MaxReceivePlaintext: 512,
				},
			},
			messageLen: 1024,
			flags: []string{
				"-max-send-fragment", "512",
				"-read-size", "1024",
			},
		},
		{
			// Test the TLS 1.2 server so there is a large
			// unencrypted certificate as well as application data.
			testType: serverTest,
			name:     "MaxSendFragment-TLS12-TooLarge",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					// Ensure that some of the records are
					// 512.
					MaxReceivePlaintext: 511,
				},
			},
			messageLen: 1024,
			flags: []string{
				"-max-send-fragment", "512",
				"-read-size", "1024",
			},
			shouldFail:         true,
			expectedLocalError: "local error: record overflow",
		},
		{
			// Test the TLS 1.3 server so there is a large encrypted
			// certificate as well as application data.
			testType: serverTest,
			name:     "MaxSendFragment-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					MaxReceivePlaintext:            512,
					ExpectPackedEncryptedHandshake: 512,
				},
			},
			messageLen: 1024,
			flags: []string{
				"-max-send-fragment", "512",
				"-read-size", "1024",
			},
		},
		{
			// Test the TLS 1.3 server so there is a large encrypted
			// certificate as well as application data.
			testType: serverTest,
			name:     "MaxSendFragment-TLS13-TooLarge",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					// Ensure that some of the records are
					// 512.
					MaxReceivePlaintext: 511,
				},
			},
			messageLen: 1024,
			flags: []string{
				"-max-send-fragment", "512",
				"-read-size", "1024",
			},
			shouldFail:         true,
			expectedLocalError: "local error: record overflow",
		},
		{
			// Test that handshake data is tightly packed in TLS 1.3.
			testType: serverTest,
			name:     "PackedEncryptedHandshake-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					ExpectPackedEncryptedHandshake: 16384,
				},
			},
		},
		{
			// Test that DTLS can handle multiple application data
			// records in a single packet.
			protocol: dtls,
			name:     "SplitAndPackAppData-DTLS",
			config: Config{
				Bugs: ProtocolBugs{
					SplitAndPackAppData: true,
				},
			},
		},
		{
			protocol: dtls,
			name:     "SplitAndPackAppData-DTLS-Async",
			config: Config{
				Bugs: ProtocolBugs{
					SplitAndPackAppData: true,
				},
			},
			flags: []string{"-async"},
		},
		{
			// DTLS 1.2 allows up to a 255-byte HelloVerifyRequest cookie, which
			// is the largest encodable value.
			protocol: dtls,
			name:     "DTLS-HelloVerifyRequest-255",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					HelloVerifyRequestCookieLength: 255,
				},
			},
		},
		{
			// DTLS 1.2 allows up to a 0-byte HelloVerifyRequest cookie, which
			// was probably a mistake in the spec but test that it works
			// nonetheless.
			protocol: dtls,
			name:     "DTLS-HelloVerifyRequest-0",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					EmptyHelloVerifyRequestCookie: true,
				},
			},
		},
	}
	testCases = append(testCases, basicTests...)

	// Test that very large messages can be received.
	cert := rsaCertificate
	for i := 0; i < 50; i++ {
		cert.Certificate = append(cert.Certificate, cert.Certificate[0])
	}
	testCases = append(testCases, testCase{
		name: "LargeMessage",
		config: Config{
			Credential: &cert,
		},
	})
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "LargeMessage-DTLS",
		config: Config{
			Credential: &cert,
		},
	})

	// They are rejected if the maximum certificate chain length is capped.
	testCases = append(testCases, testCase{
		name: "LargeMessage-Reject",
		config: Config{
			Credential: &cert,
		},
		flags:         []string{"-max-cert-list", "16384"},
		shouldFail:    true,
		expectedError: ":EXCESSIVE_MESSAGE_SIZE:",
	})
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "LargeMessage-Reject-DTLS",
		config: Config{
			Credential: &cert,
		},
		flags:         []string{"-max-cert-list", "16384"},
		shouldFail:    true,
		expectedError: ":EXCESSIVE_MESSAGE_SIZE:",
	})

	// Servers echoing the TLS 1.3 compatibility mode session ID should be
	// rejected.
	testCases = append(testCases, testCase{
		name: "EchoTLS13CompatibilitySessionID",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				EchoSessionIDInFullHandshake: true,
			},
		},
		shouldFail:         true,
		expectedError:      ":SERVER_ECHOED_INVALID_SESSION_ID:",
		expectedLocalError: "remote error: illegal parameter",
	})

	// Servers should reject QUIC client hellos that have a legacy
	// session ID.
	testCases = append(testCases, testCase{
		name:     "QUICCompatibilityMode",
		testType: serverTest,
		protocol: quic,
		config: Config{
			MinVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				CompatModeWithQUIC: true,
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_COMPATIBILITY_MODE:",
	})

	// Clients should reject DTLS 1.3 ServerHellos that echo the legacy
	// session ID.
	testCases = append(testCases, testCase{
		protocol:      dtls,
		name:          "DTLS13CompatibilityMode-EchoSessionID",
		resumeSession: true,
		config: Config{
			MaxVersion: VersionTLS12,
		},
		resumeConfig: &Config{
			MinVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				DTLS13EchoSessionID: true,
			},
		},
		shouldFail:    true,
		expectedError: ":DECODE_ERROR:",
	})

	// DTLS 1.3 should work with record headers that don't set the
	// length bit or that use the short sequence number format.
	testCases = append(testCases, testCase{
		testType: clientTest,
		protocol: dtls,
		name:     "DTLS13RecordHeader-NoLength-Client",
		config: Config{
			MinVersion:                 VersionTLS13,
			DTLSRecordHeaderOmitLength: true,
		},
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		protocol: dtls,
		name:     "DTLS13RecordHeader-NoLength-Server",
		config: Config{
			MinVersion:                 VersionTLS13,
			DTLSRecordHeaderOmitLength: true,
		},
	})
	testCases = append(testCases, testCase{
		testType: clientTest,
		protocol: dtls,
		name:     "DTLS13RecordHeader-ShortSeqNums-Client",
		config: Config{
			MinVersion:          VersionTLS13,
			DTLSUseShortSeqNums: true,
		},
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		protocol: dtls,
		name:     "DTLS13RecordHeader-ShortSeqNums-Server",
		config: Config{
			MinVersion:          VersionTLS13,
			DTLSUseShortSeqNums: true,
		},
	})
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "DTLS13RecordHeader-OldHeader",
		config: Config{
			MinVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				DTLSUsePlaintextRecordHeader: true,
			},
		},
		expectMessageDropped: true,
	})
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "DTLS13RecordHeader-CIDBit",
		config: Config{
			MinVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				DTLS13RecordHeaderSetCIDBit: true,
			},
		},
		expectMessageDropped: true,
	})

	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "DTLS13-MessageCallback-Client",
		config: Config{
			MaxVersion: VersionTLS13,
			MinVersion: VersionTLS13,
		},
		flags: []string{
			"-expect-msg-callback",
			`write hs 1
read hs 2
read hs 8
read hs 11
read hs 15
read hs 20
write hs 20
read ack
read hs 4
read hs 4
read alert 1 0
`,
		},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		protocol: dtls,
		name:     "DTLS13-MessageCallback-Server",
		config: Config{
			MaxVersion: VersionTLS13,
			MinVersion: VersionTLS13,
		},
		flags: []string{
			"-expect-msg-callback",
			`read hs 1
write hs 2
write hs 8
write hs 11
write hs 15
write hs 20
read hs 20
write ack
write hs 4
write hs 4
read ack
read ack
read alert 1 0
`,
		},
	})
}

func addTestForCipherSuite(suite testCipherSuite, ver tlsVersion, protocol protocol) {
	const psk = "12345"
	const pskIdentity = "luggage combo"

	if !ver.supportsProtocol(protocol) {
		return
	}
	prefix := protocol.String() + "-"

	var cert *Credential
	if isTLS13Suite(suite.name) {
		cert = &rsaCertificate
	} else if hasComponent(suite.name, "ECDSA") {
		cert = &ecdsaP256Certificate
	} else if hasComponent(suite.name, "RSA") {
		cert = &rsaCertificate
	}

	var flags []string
	if hasComponent(suite.name, "PSK") {
		flags = append(flags,
			"-psk", psk,
			"-psk-identity", pskIdentity)
	}

	if hasComponent(suite.name, "3DES") {
		// BoringSSL disables 3DES ciphers by default.
		flags = append(flags, "-cipher", "3DES")
	}

	var shouldFail bool
	if isTLS12Only(suite.name) && ver.version < VersionTLS12 {
		shouldFail = true
	}
	if !isTLS13Suite(suite.name) && ver.version >= VersionTLS13 {
		shouldFail = true
	}
	if isTLS13Suite(suite.name) && ver.version < VersionTLS13 {
		shouldFail = true
	}

	var sendCipherSuite uint16
	var expectedServerError, expectedClientError string
	serverCipherSuites := []uint16{suite.id}
	if shouldFail {
		expectedServerError = ":NO_SHARED_CIPHER:"
		if ver.version >= VersionTLS13 && cert == nil {
			// TLS 1.2 PSK ciphers won't configure a server certificate, but we
			// require one in TLS 1.3.
			expectedServerError = ":NO_CERTIFICATE_SET:"
		}
		expectedClientError = ":WRONG_CIPHER_RETURNED:"
		// Configure the server to select ciphers as normal but
		// select an incompatible cipher in ServerHello.
		serverCipherSuites = nil
		sendCipherSuite = suite.id
	}

	// Verify exporters interoperate.
	exportKeyingMaterial := 1024

	if ver.version != VersionTLS13 || !ver.hasDTLS {
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + ver.name + "-" + suite.name + "-server",
			config: Config{
				MinVersion:           ver.version,
				MaxVersion:           ver.version,
				CipherSuites:         []uint16{suite.id},
				Credential:           cert,
				PreSharedKey:         []byte(psk),
				PreSharedKeyIdentity: pskIdentity,
				Bugs: ProtocolBugs{
					AdvertiseAllConfiguredCiphers: true,
				},
			},
			shimCertificate:      cert,
			flags:                flags,
			resumeSession:        true,
			shouldFail:           shouldFail,
			expectedError:        expectedServerError,
			exportKeyingMaterial: exportKeyingMaterial,
		})

		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + ver.name + "-" + suite.name + "-client",
			config: Config{
				MinVersion:           ver.version,
				MaxVersion:           ver.version,
				CipherSuites:         serverCipherSuites,
				Credential:           cert,
				PreSharedKey:         []byte(psk),
				PreSharedKeyIdentity: pskIdentity,
				Bugs: ProtocolBugs{
					IgnorePeerCipherPreferences: shouldFail,
					SendCipherSuite:             sendCipherSuite,
				},
			},
			flags:                flags,
			resumeSession:        true,
			shouldFail:           shouldFail,
			expectedError:        expectedClientError,
			exportKeyingMaterial: exportKeyingMaterial,
		})
	}

	if shouldFail {
		return
	}

	// Ensure the maximum record size is accepted.
	testCases = append(testCases, testCase{
		protocol: protocol,
		name:     prefix + ver.name + "-" + suite.name + "-LargeRecord",
		config: Config{
			MinVersion:           ver.version,
			MaxVersion:           ver.version,
			CipherSuites:         []uint16{suite.id},
			Credential:           cert,
			PreSharedKey:         []byte(psk),
			PreSharedKeyIdentity: pskIdentity,
		},
		flags:      flags,
		messageLen: maxPlaintext,
	})

	// Test bad records for all ciphers. Bad records are fatal in TLS
	// and ignored in DTLS.
	shouldFail = protocol == tls
	var expectedError string
	if shouldFail {
		expectedError = ":DECRYPTION_FAILED_OR_BAD_RECORD_MAC:"
	}

	// When QUIC is used, the QUIC stack handles record encryption/decryption.
	// Thus it is not possible for the TLS stack in QUIC mode to receive a
	// bad record (i.e. one that fails to decrypt).
	if protocol != quic {
		testCases = append(testCases, testCase{
			protocol: protocol,
			name:     prefix + ver.name + "-" + suite.name + "-BadRecord",
			config: Config{
				MinVersion:           ver.version,
				MaxVersion:           ver.version,
				CipherSuites:         []uint16{suite.id},
				Credential:           cert,
				PreSharedKey:         []byte(psk),
				PreSharedKeyIdentity: pskIdentity,
			},
			flags:            flags,
			damageFirstWrite: true,
			messageLen:       maxPlaintext,
			shouldFail:       shouldFail,
			expectedError:    expectedError,
		})
	}
}

func addCipherSuiteTests() {
	const bogusCipher = 0xfe00

	for _, suite := range testCipherSuites {
		for _, ver := range tlsVersions {
			for _, protocol := range []protocol{tls, dtls, quic} {
				addTestForCipherSuite(suite, ver, protocol)
			}
		}
	}

	testCases = append(testCases, testCase{
		name: "NoSharedCipher",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{},
		},
		shouldFail:    true,
		expectedError: ":HANDSHAKE_FAILURE_ON_CLIENT_HELLO:",
	})

	testCases = append(testCases, testCase{
		name: "NoSharedCipher-TLS13",
		config: Config{
			MaxVersion:   VersionTLS13,
			CipherSuites: []uint16{},
		},
		shouldFail:    true,
		expectedError: ":HANDSHAKE_FAILURE_ON_CLIENT_HELLO:",
	})

	testCases = append(testCases, testCase{
		name: "UnsupportedCipherSuite",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_RSA_WITH_AES_128_CBC_SHA},
			Bugs: ProtocolBugs{
				IgnorePeerCipherPreferences: true,
			},
		},
		flags:         []string{"-cipher", "DEFAULT:!AES"},
		shouldFail:    true,
		expectedError: ":WRONG_CIPHER_RETURNED:",
	})

	testCases = append(testCases, testCase{
		name: "ServerHelloBogusCipher",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SendCipherSuite: bogusCipher,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_CIPHER_RETURNED:",
	})
	testCases = append(testCases, testCase{
		name: "ServerHelloBogusCipher-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendCipherSuite: bogusCipher,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_CIPHER_RETURNED:",
	})

	// The server must be tolerant to bogus ciphers.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "UnknownCipher",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{bogusCipher, TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			Bugs: ProtocolBugs{
				AdvertiseAllConfiguredCiphers: true,
			},
		},
	})

	// The server must be tolerant to bogus ciphers.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "UnknownCipher-TLS13",
		config: Config{
			MaxVersion:   VersionTLS13,
			CipherSuites: []uint16{bogusCipher, TLS_AES_128_GCM_SHA256},
			Bugs: ProtocolBugs{
				AdvertiseAllConfiguredCiphers: true,
			},
		},
	})

	// Test empty ECDHE_PSK identity hints work as expected.
	testCases = append(testCases, testCase{
		name: "EmptyECDHEPSKHint",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA},
			PreSharedKey: []byte("secret"),
		},
		flags: []string{"-psk", "secret"},
	})

	// Test empty PSK identity hints work as expected, even if an explicit
	// ServerKeyExchange is sent.
	testCases = append(testCases, testCase{
		name: "ExplicitEmptyPSKHint",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_PSK_WITH_AES_128_CBC_SHA},
			PreSharedKey: []byte("secret"),
			Bugs: ProtocolBugs{
				AlwaysSendPreSharedKeyIdentityHint: true,
			},
		},
		flags: []string{"-psk", "secret"},
	})

	// Test that clients enforce that the server-sent certificate and cipher
	// suite match in TLS 1.2.
	testCases = append(testCases, testCase{
		name: "CertificateCipherMismatch-RSA",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			Credential:   &rsaCertificate,
			Bugs: ProtocolBugs{
				SendCipherSuite: TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_CERTIFICATE_TYPE:",
	})
	testCases = append(testCases, testCase{
		name: "CertificateCipherMismatch-ECDSA",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256},
			Credential:   &ecdsaP256Certificate,
			Bugs: ProtocolBugs{
				SendCipherSuite: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_CERTIFICATE_TYPE:",
	})
	testCases = append(testCases, testCase{
		name: "CertificateCipherMismatch-Ed25519",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256},
			Credential:   &ed25519Certificate,
			Bugs: ProtocolBugs{
				SendCipherSuite: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_CERTIFICATE_TYPE:",
	})

	// Test that servers decline to select a cipher suite which is
	// inconsistent with their configured certificate.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ServerCipherFilter-RSA",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256},
		},
		shimCertificate: &rsaCertificate,
		shouldFail:      true,
		expectedError:   ":NO_SHARED_CIPHER:",
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ServerCipherFilter-ECDSA",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
		},
		shimCertificate: &ecdsaP256Certificate,
		shouldFail:      true,
		expectedError:   ":NO_SHARED_CIPHER:",
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ServerCipherFilter-Ed25519",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
		},
		shimCertificate: &ed25519Certificate,
		shouldFail:      true,
		expectedError:   ":NO_SHARED_CIPHER:",
	})

	// Test cipher suite negotiation works as expected. Configure a
	// complicated cipher suite configuration.
	const negotiationTestCiphers = "" +
		"TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256:" +
		"[TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384|TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256|TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA]:" +
		"TLS_RSA_WITH_AES_128_GCM_SHA256:" +
		"TLS_RSA_WITH_AES_128_CBC_SHA:" +
		"[TLS_RSA_WITH_AES_256_GCM_SHA384|TLS_RSA_WITH_AES_256_CBC_SHA]"
	negotiationTests := []struct {
		ciphers  []uint16
		expected uint16
	}{
		// Server preferences are honored, including when
		// equipreference groups are involved.
		{
			[]uint16{
				TLS_RSA_WITH_AES_256_GCM_SHA384,
				TLS_RSA_WITH_AES_128_CBC_SHA,
				TLS_RSA_WITH_AES_128_GCM_SHA256,
				TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
				TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
			},
			TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
		},
		{
			[]uint16{
				TLS_RSA_WITH_AES_256_GCM_SHA384,
				TLS_RSA_WITH_AES_128_CBC_SHA,
				TLS_RSA_WITH_AES_128_GCM_SHA256,
				TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
			},
			TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
		},
		{
			[]uint16{
				TLS_RSA_WITH_AES_256_GCM_SHA384,
				TLS_RSA_WITH_AES_128_CBC_SHA,
				TLS_RSA_WITH_AES_128_GCM_SHA256,
			},
			TLS_RSA_WITH_AES_128_GCM_SHA256,
		},
		{
			[]uint16{
				TLS_RSA_WITH_AES_256_GCM_SHA384,
				TLS_RSA_WITH_AES_128_CBC_SHA,
			},
			TLS_RSA_WITH_AES_128_CBC_SHA,
		},
		// Equipreference groups use the client preference.
		{
			[]uint16{
				TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
				TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256,
				TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
			},
			TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
		},
		{
			[]uint16{
				TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256,
				TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
			},
			TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256,
		},
		{
			[]uint16{
				TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
				TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256,
			},
			TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
		},
		{
			[]uint16{
				TLS_RSA_WITH_AES_256_GCM_SHA384,
				TLS_RSA_WITH_AES_256_CBC_SHA,
			},
			TLS_RSA_WITH_AES_256_GCM_SHA384,
		},
		{
			[]uint16{
				TLS_RSA_WITH_AES_256_CBC_SHA,
				TLS_RSA_WITH_AES_256_GCM_SHA384,
			},
			TLS_RSA_WITH_AES_256_CBC_SHA,
		},
		// If there are two equipreference groups, the preferred one
		// takes precedence.
		{
			[]uint16{
				TLS_RSA_WITH_AES_256_GCM_SHA384,
				TLS_RSA_WITH_AES_256_CBC_SHA,
				TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
				TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256,
			},
			TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
		},
	}
	for i, t := range negotiationTests {
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "CipherNegotiation-" + strconv.Itoa(i),
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: t.ciphers,
			},
			flags: []string{"-cipher", negotiationTestCiphers},
			expectations: connectionExpectations{
				cipher: t.expected,
			},
		})
	}
}

func addBadECDSASignatureTests() {
	for badR := BadValue(1); badR < NumBadValues; badR++ {
		for badS := BadValue(1); badS < NumBadValues; badS++ {
			testCases = append(testCases, testCase{
				name: fmt.Sprintf("BadECDSA-%d-%d", badR, badS),
				config: Config{
					MaxVersion:   VersionTLS12,
					CipherSuites: []uint16{TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256},
					Credential:   &ecdsaP256Certificate,
					Bugs: ProtocolBugs{
						BadECDSAR: badR,
						BadECDSAS: badS,
					},
				},
				shouldFail:    true,
				expectedError: ":BAD_SIGNATURE:",
			})
			testCases = append(testCases, testCase{
				name: fmt.Sprintf("BadECDSA-%d-%d-TLS13", badR, badS),
				config: Config{
					MaxVersion: VersionTLS13,
					Credential: &ecdsaP256Certificate,
					Bugs: ProtocolBugs{
						BadECDSAR: badR,
						BadECDSAS: badS,
					},
				},
				shouldFail:    true,
				expectedError: ":BAD_SIGNATURE:",
			})
		}
	}
}

func addCBCPaddingTests() {
	testCases = append(testCases, testCase{
		name: "MaxCBCPadding",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA},
			Bugs: ProtocolBugs{
				MaxPadding: true,
			},
		},
		messageLen: 12, // 20 bytes of SHA-1 + 12 == 0 % block size
	})
	testCases = append(testCases, testCase{
		name: "BadCBCPadding",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA},
			Bugs: ProtocolBugs{
				PaddingFirstByteBad: true,
			},
		},
		shouldFail:    true,
		expectedError: ":DECRYPTION_FAILED_OR_BAD_RECORD_MAC:",
	})
	// OpenSSL previously had an issue where the first byte of padding in
	// 255 bytes of padding wasn't checked.
	testCases = append(testCases, testCase{
		name: "BadCBCPadding255",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA},
			Bugs: ProtocolBugs{
				MaxPadding:               true,
				PaddingFirstByteBadIf255: true,
			},
		},
		messageLen:    12, // 20 bytes of SHA-1 + 12 == 0 % block size
		shouldFail:    true,
		expectedError: ":DECRYPTION_FAILED_OR_BAD_RECORD_MAC:",
	})
}

func addCBCSplittingTests() {
	cbcCiphers := []struct {
		name   string
		cipher uint16
	}{
		{"3DES", TLS_RSA_WITH_3DES_EDE_CBC_SHA},
		{"AES128", TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA},
		{"AES256", TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA},
	}
	for _, t := range cbcCiphers {
		testCases = append(testCases, testCase{
			name: "CBCRecordSplitting-" + t.name,
			config: Config{
				MaxVersion:   VersionTLS10,
				MinVersion:   VersionTLS10,
				CipherSuites: []uint16{t.cipher},
				Bugs: ProtocolBugs{
					ExpectRecordSplitting: true,
				},
			},
			messageLen:    -1, // read until EOF
			resumeSession: true,
			flags: []string{
				"-async",
				"-write-different-record-sizes",
				"-cbc-record-splitting",
				// BoringSSL disables 3DES by default.
				"-cipher", "ALL:3DES",
			},
		})
		testCases = append(testCases, testCase{
			name: "CBCRecordSplittingPartialWrite-" + t.name,
			config: Config{
				MaxVersion:   VersionTLS10,
				MinVersion:   VersionTLS10,
				CipherSuites: []uint16{t.cipher},
				Bugs: ProtocolBugs{
					ExpectRecordSplitting: true,
				},
			},
			messageLen: -1, // read until EOF
			flags: []string{
				"-async",
				"-write-different-record-sizes",
				"-cbc-record-splitting",
				"-partial-write",
				// BoringSSL disables 3DES by default.
				"-cipher", "ALL:3DES",
			},
		})
	}
}

func makeCertPoolFromRoots(creds ...*Credential) *x509.CertPool {
	certPool := x509.NewCertPool()
	for _, cred := range creds {
		cert, err := x509.ParseCertificate(cred.RootCertificate)
		if err != nil {
			panic(err)
		}
		certPool.AddCert(cert)
	}
	return certPool
}

func addClientAuthTests() {
	// Add a dummy cert pool to stress certificate authority parsing.
	certPool := makeCertPoolFromRoots(&rsaCertificate, &rsa1024Certificate)
	caNames := certPool.Subjects()

	for _, ver := range tlsVersions {
		testCases = append(testCases, testCase{
			testType: clientTest,
			name:     ver.name + "-Client-ClientAuth-RSA",
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				ClientAuth: RequireAnyClientCert,
				ClientCAs:  certPool,
			},
			shimCertificate: &rsaCertificate,
		})
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     ver.name + "-Server-ClientAuth-RSA",
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Credential: &rsaCertificate,
			},
			flags: []string{"-require-any-client-certificate"},
		})
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     ver.name + "-Server-ClientAuth-ECDSA",
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Credential: &ecdsaP256Certificate,
			},
			flags: []string{"-require-any-client-certificate"},
		})
		testCases = append(testCases, testCase{
			testType: clientTest,
			name:     ver.name + "-Client-ClientAuth-ECDSA",
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				ClientAuth: RequireAnyClientCert,
				ClientCAs:  certPool,
			},
			shimCertificate: &ecdsaP256Certificate,
		})

		testCases = append(testCases, testCase{
			name: "NoClientCertificate-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				ClientAuth: RequireAnyClientCert,
			},
			shouldFail:         true,
			expectedLocalError: "client didn't provide a certificate",
		})

		testCases = append(testCases, testCase{
			// Even if not configured to expect a certificate, OpenSSL will
			// return X509_V_OK as the verify_result.
			testType: serverTest,
			name:     "NoClientCertificateRequested-Server-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
			},
			flags: []string{
				"-expect-verify-result",
			},
			resumeSession: true,
		})

		testCases = append(testCases, testCase{
			// If a client certificate is not provided, OpenSSL will still
			// return X509_V_OK as the verify_result.
			testType: serverTest,
			name:     "NoClientCertificate-Server-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
			},
			flags: []string{
				"-expect-verify-result",
				"-verify-peer",
			},
			resumeSession: true,
		})

		certificateRequired := "remote error: certificate required"
		if ver.version < VersionTLS13 {
			// Prior to TLS 1.3, the generic handshake_failure alert
			// was used.
			certificateRequired = "remote error: handshake failure"
		}
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "RequireAnyClientCertificate-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
			},
			flags:              []string{"-require-any-client-certificate"},
			shouldFail:         true,
			expectedError:      ":PEER_DID_NOT_RETURN_A_CERTIFICATE:",
			expectedLocalError: certificateRequired,
		})

		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "SkipClientCertificate-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Bugs: ProtocolBugs{
					SkipClientCertificate: true,
				},
			},
			// Setting SSL_VERIFY_PEER allows anonymous clients.
			flags:         []string{"-verify-peer"},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_MESSAGE:",
		})

		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     ver.name + "-Server-CertReq-CA-List",
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Credential: &rsaCertificate,
				Bugs: ProtocolBugs{
					ExpectCertificateReqNames: caNames,
				},
			},
			flags: []string{
				"-require-any-client-certificate",
				"-use-client-ca-list", encodeDERValues(caNames),
			},
		})

		testCases = append(testCases, testCase{
			testType: clientTest,
			name:     ver.name + "-Client-CertReq-CA-List",
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Credential: &rsaCertificate,
				ClientAuth: RequireAnyClientCert,
				ClientCAs:  certPool,
			},
			shimCertificate: &rsaCertificate,
			flags: []string{
				"-expect-client-ca-list", encodeDERValues(caNames),
			},
		})
	}

	// Client auth is only legal in certificate-based ciphers.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "ClientAuth-PSK",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_PSK_WITH_AES_128_CBC_SHA},
			PreSharedKey: []byte("secret"),
			ClientAuth:   RequireAnyClientCert,
		},
		shimCertificate: &rsaCertificate,
		flags: []string{
			"-psk", "secret",
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_MESSAGE:",
	})
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "ClientAuth-ECDHE_PSK",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA},
			PreSharedKey: []byte("secret"),
			ClientAuth:   RequireAnyClientCert,
		},
		shimCertificate: &rsaCertificate,
		flags: []string{
			"-psk", "secret",
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_MESSAGE:",
	})

	// Regression test for a bug where the client CA list, if explicitly
	// set to NULL, was mis-encoded.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "Null-Client-CA-List",
		config: Config{
			MaxVersion: VersionTLS12,
			Credential: &rsaCertificate,
			Bugs: ProtocolBugs{
				ExpectCertificateReqNames: [][]byte{},
			},
		},
		flags: []string{
			"-require-any-client-certificate",
			"-use-client-ca-list", "<NULL>",
		},
	})

	// Test that an empty client CA list doesn't send a CA extension.
	// (This is implicitly tested by the parser. An empty CA extension is
	// a syntax error.)
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "TLS13-Empty-Client-CA-List",
		config: Config{
			MaxVersion: VersionTLS13,
			Credential: &rsaCertificate,
		},
		flags: []string{
			"-require-any-client-certificate",
			"-use-client-ca-list", "<EMPTY>",
		},
	})
}

func addExtendedMasterSecretTests() {
	const expectEMSFlag = "-expect-extended-master-secret"

	for _, with := range []bool{false, true} {
		prefix := "No"
		if with {
			prefix = ""
		}

		for _, isClient := range []bool{false, true} {
			suffix := "-Server"
			testType := serverTest
			if isClient {
				suffix = "-Client"
				testType = clientTest
			}

			for _, ver := range tlsVersions {
				// In TLS 1.3, the extension is irrelevant and
				// always reports as enabled.
				var flags []string
				if with || ver.version >= VersionTLS13 {
					flags = []string{expectEMSFlag}
				}

				testCases = append(testCases, testCase{
					testType: testType,
					name:     prefix + "ExtendedMasterSecret-" + ver.name + suffix,
					config: Config{
						MinVersion: ver.version,
						MaxVersion: ver.version,
						Bugs: ProtocolBugs{
							NoExtendedMasterSecret:      !with,
							RequireExtendedMasterSecret: with,
						},
					},
					flags: flags,
				})
			}
		}
	}

	for _, isClient := range []bool{false, true} {
		for _, supportedInFirstConnection := range []bool{false, true} {
			for _, supportedInResumeConnection := range []bool{false, true} {
				boolToWord := func(b bool) string {
					if b {
						return "Yes"
					}
					return "No"
				}
				suffix := boolToWord(supportedInFirstConnection) + "To" + boolToWord(supportedInResumeConnection) + "-"
				if isClient {
					suffix += "Client"
				} else {
					suffix += "Server"
				}

				supportedConfig := Config{
					MaxVersion: VersionTLS12,
					Bugs: ProtocolBugs{
						RequireExtendedMasterSecret: true,
					},
				}

				noSupportConfig := Config{
					MaxVersion: VersionTLS12,
					Bugs: ProtocolBugs{
						NoExtendedMasterSecret: true,
					},
				}

				test := testCase{
					name:          "ExtendedMasterSecret-" + suffix,
					resumeSession: true,
				}

				if !isClient {
					test.testType = serverTest
				}

				if supportedInFirstConnection {
					test.config = supportedConfig
				} else {
					test.config = noSupportConfig
				}

				if supportedInResumeConnection {
					test.resumeConfig = &supportedConfig
				} else {
					test.resumeConfig = &noSupportConfig
				}

				switch suffix {
				case "YesToYes-Client", "YesToYes-Server":
					// When a session is resumed, it should
					// still be aware that its master
					// secret was generated via EMS and
					// thus it's safe to use tls-unique.
					test.flags = []string{expectEMSFlag}
				case "NoToYes-Server":
					// If an original connection did not
					// contain EMS, but a resumption
					// handshake does, then a server should
					// not resume the session.
					test.expectResumeRejected = true
				case "YesToNo-Server":
					// Resuming an EMS session without the
					// EMS extension should cause the
					// server to abort the connection.
					test.shouldFail = true
					test.expectedError = ":RESUMED_EMS_SESSION_WITHOUT_EMS_EXTENSION:"
				case "NoToYes-Client":
					// A client should abort a connection
					// where the server resumed a non-EMS
					// session but echoed the EMS
					// extension.
					test.shouldFail = true
					test.expectedError = ":RESUMED_NON_EMS_SESSION_WITH_EMS_EXTENSION:"
				case "YesToNo-Client":
					// A client should abort a connection
					// where the server didn't echo EMS
					// when the session used it.
					test.shouldFail = true
					test.expectedError = ":RESUMED_EMS_SESSION_WITHOUT_EMS_EXTENSION:"
				}

				testCases = append(testCases, test)
			}
		}
	}

	// Switching EMS on renegotiation is forbidden.
	testCases = append(testCases, testCase{
		name: "ExtendedMasterSecret-Renego-NoEMS",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				NoExtendedMasterSecret:                true,
				NoExtendedMasterSecretOnRenegotiation: true,
			},
		},
		renegotiate: 1,
		flags: []string{
			"-renegotiate-freely",
			"-expect-total-renegotiations", "1",
		},
	})

	testCases = append(testCases, testCase{
		name: "ExtendedMasterSecret-Renego-Upgrade",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				NoExtendedMasterSecret: true,
			},
		},
		renegotiate: 1,
		flags: []string{
			"-renegotiate-freely",
			"-expect-total-renegotiations", "1",
		},
		shouldFail:    true,
		expectedError: ":RENEGOTIATION_EMS_MISMATCH:",
	})

	testCases = append(testCases, testCase{
		name: "ExtendedMasterSecret-Renego-Downgrade",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				NoExtendedMasterSecretOnRenegotiation: true,
			},
		},
		renegotiate: 1,
		flags: []string{
			"-renegotiate-freely",
			"-expect-total-renegotiations", "1",
		},
		shouldFail:    true,
		expectedError: ":RENEGOTIATION_EMS_MISMATCH:",
	})
}

type stateMachineTestConfig struct {
	protocol          protocol
	async             bool
	splitHandshake    bool
	packHandshake     bool
	implicitHandshake bool
}

// Adds tests that try to cover the range of the handshake state machine, under
// various conditions. Some of these are redundant with other tests, but they
// only cover the synchronous case.
func addAllStateMachineCoverageTests() {
	for _, async := range []bool{false, true} {
		for _, protocol := range []protocol{tls, dtls, quic} {
			addStateMachineCoverageTests(stateMachineTestConfig{
				protocol: protocol,
				async:    async,
			})
			// QUIC doesn't work with the implicit handshake API. Additionally,
			// splitting or packing handshake records is meaningless in QUIC.
			if protocol != quic {
				addStateMachineCoverageTests(stateMachineTestConfig{
					protocol:          protocol,
					async:             async,
					implicitHandshake: true,
				})
				addStateMachineCoverageTests(stateMachineTestConfig{
					protocol:       protocol,
					async:          async,
					splitHandshake: true,
				})
				addStateMachineCoverageTests(stateMachineTestConfig{
					protocol:      protocol,
					async:         async,
					packHandshake: true,
				})
			}
		}
	}
}

func addStateMachineCoverageTests(config stateMachineTestConfig) {
	var tests []testCase

	// Basic handshake, with resumption. Client and server,
	// session ID and session ticket.
	// The following tests have a max version of 1.2, so they are not suitable
	// for use with QUIC.
	if config.protocol != quic {
		tests = append(tests, testCase{
			name: "Basic-Client",
			config: Config{
				MaxVersion: VersionTLS12,
			},
			resumeSession: true,
			// Ensure session tickets are used, not session IDs.
			noSessionCache: true,
			flags:          []string{"-expect-no-hrr"},
		})
		tests = append(tests, testCase{
			name: "Basic-Client-RenewTicket",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					RenewTicketOnResume: true,
				},
			},
			flags:                []string{"-expect-ticket-renewal"},
			resumeSession:        true,
			resumeRenewedSession: true,
		})
		tests = append(tests, testCase{
			name: "Basic-Client-NoTicket",
			config: Config{
				MaxVersion:             VersionTLS12,
				SessionTicketsDisabled: true,
			},
			resumeSession: true,
		})
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "Basic-Server",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					RequireSessionTickets: true,
				},
			},
			resumeSession: true,
			flags: []string{
				"-expect-no-session-id",
				"-expect-no-hrr",
			},
		})
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "Basic-Server-NoTickets",
			config: Config{
				MaxVersion:             VersionTLS12,
				SessionTicketsDisabled: true,
			},
			resumeSession: true,
			flags:         []string{"-expect-session-id"},
		})
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "Basic-Server-EarlyCallback",
			config: Config{
				MaxVersion: VersionTLS12,
			},
			flags:         []string{"-use-early-callback"},
			resumeSession: true,
		})
	}

	// TLS 1.3 basic handshake shapes.
	tests = append(tests, testCase{
		name: "TLS13-1RTT-Client",
		config: Config{
			MaxVersion: VersionTLS13,
			MinVersion: VersionTLS13,
		},
		resumeSession:        true,
		resumeRenewedSession: true,
		// 0-RTT being disabled overrides all other 0-RTT reasons.
		flags: []string{"-expect-early-data-reason", "disabled"},
	})

	tests = append(tests, testCase{
		testType: serverTest,
		name:     "TLS13-1RTT-Server",
		config: Config{
			MaxVersion: VersionTLS13,
			MinVersion: VersionTLS13,
		},
		resumeSession:        true,
		resumeRenewedSession: true,
		flags: []string{
			// TLS 1.3 uses tickets, so the session should not be
			// cached statefully.
			"-expect-no-session-id",
			// 0-RTT being disabled overrides all other 0-RTT reasons.
			"-expect-early-data-reason", "disabled",
		},
	})

	tests = append(tests, testCase{
		name: "TLS13-HelloRetryRequest-Client",
		config: Config{
			MaxVersion: VersionTLS13,
			MinVersion: VersionTLS13,
			// P-384 requires a HelloRetryRequest against BoringSSL's default
			// configuration. Assert this with ExpectMissingKeyShare.
			CurvePreferences: []CurveID{CurveP384},
			Bugs: ProtocolBugs{
				ExpectMissingKeyShare: true,
			},
		},
		// Cover HelloRetryRequest during an ECDHE-PSK resumption.
		resumeSession: true,
		flags:         []string{"-expect-hrr"},
	})

	tests = append(tests, testCase{
		testType: serverTest,
		name:     "TLS13-HelloRetryRequest-Server",
		config: Config{
			MaxVersion: VersionTLS13,
			MinVersion: VersionTLS13,
			// Require a HelloRetryRequest for every curve.
			DefaultCurves: []CurveID{},
		},
		// Cover HelloRetryRequest during an ECDHE-PSK resumption.
		resumeSession: true,
		flags:         []string{"-expect-hrr"},
	})

	// TLS 1.3 early data tests. DTLS 1.3 doesn't support early data yet.
	// These tests are disabled for QUIC as well because they test features
	// that do not apply to QUIC's use of TLS 1.3.
	//
	// TODO(crbug.com/381113363): Enable these tests for DTLS once we
	// support early data in DTLS 1.3.
	if config.protocol != dtls && config.protocol != quic {
		tests = append(tests, testCase{
			testType: clientTest,
			name:     "TLS13-EarlyData-TooMuchData-Client",
			config: Config{
				MaxVersion:       VersionTLS13,
				MinVersion:       VersionTLS13,
				MaxEarlyDataSize: 2,
			},
			resumeConfig: &Config{
				MaxVersion:       VersionTLS13,
				MinVersion:       VersionTLS13,
				MaxEarlyDataSize: 2,
				Bugs: ProtocolBugs{
					ExpectEarlyData: [][]byte{[]byte(shimInitialWrite[:2])},
				},
			},
			resumeShimPrefix: shimInitialWrite[2:],
			resumeSession:    true,
			earlyData:        true,
		})

		// Unfinished writes can only be tested when operations are async. EarlyData
		// can't be tested as part of an ImplicitHandshake in this case since
		// otherwise the early data will be sent as normal data.
		if config.async && !config.implicitHandshake {
			tests = append(tests, testCase{
				testType: clientTest,
				name:     "TLS13-EarlyData-UnfinishedWrite-Client",
				config: Config{
					MaxVersion: VersionTLS13,
					MinVersion: VersionTLS13,
					Bugs: ProtocolBugs{
						// Write the server response before expecting early data.
						ExpectEarlyData:     [][]byte{},
						ExpectLateEarlyData: [][]byte{[]byte(shimInitialWrite)},
					},
				},
				resumeSession: true,
				earlyData:     true,
				flags:         []string{"-on-resume-read-with-unfinished-write"},
			})

			// Rejected unfinished writes are discarded (from the
			// perspective of the calling application) on 0-RTT
			// reject.
			tests = append(tests, testCase{
				testType: clientTest,
				name:     "TLS13-EarlyData-RejectUnfinishedWrite-Client",
				config: Config{
					MaxVersion: VersionTLS13,
					MinVersion: VersionTLS13,
					Bugs: ProtocolBugs{
						AlwaysRejectEarlyData: true,
					},
				},
				resumeSession:           true,
				earlyData:               true,
				expectEarlyDataRejected: true,
				flags:                   []string{"-on-resume-read-with-unfinished-write"},
			})
		}

		// Early data has no size limit in QUIC.
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "TLS13-MaxEarlyData-Server",
			config: Config{
				MaxVersion: VersionTLS13,
				MinVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					SendEarlyData:           [][]byte{bytes.Repeat([]byte{1}, 14336+1)},
					ExpectEarlyDataAccepted: true,
				},
			},
			messageCount:  2,
			resumeSession: true,
			earlyData:     true,
			shouldFail:    true,
			expectedError: ":TOO_MUCH_READ_EARLY_DATA:",
		})
	}

	// Test that early data is disabled for DTLS 1.3.
	if config.protocol == dtls {
		tests = append(tests, testCase{
			testType: clientTest,
			protocol: dtls,
			name:     "DTLS13-EarlyData",
			config: Config{
				MaxVersion: VersionTLS13,
				MinVersion: VersionTLS13,
			},
			resumeSession: true,
			earlyData:     true,
		})
	}

	// TLS client auth.
	// The following tests have a max version of 1.2, so they are not suitable
	// for use with QUIC.
	if config.protocol != quic {
		tests = append(tests, testCase{
			testType: clientTest,
			name:     "ClientAuth-NoCertificate-Client",
			config: Config{
				MaxVersion: VersionTLS12,
				ClientAuth: RequestClientCert,
			},
		})
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "ClientAuth-NoCertificate-Server",
			config: Config{
				MaxVersion: VersionTLS12,
			},
			// Setting SSL_VERIFY_PEER allows anonymous clients.
			flags: []string{"-verify-peer"},
		})
	}
	if config.protocol != dtls {
		tests = append(tests, testCase{
			testType: clientTest,
			name:     "ClientAuth-NoCertificate-Client-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
				ClientAuth: RequestClientCert,
			},
		})
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "ClientAuth-NoCertificate-Server-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
			},
			// Setting SSL_VERIFY_PEER allows anonymous clients.
			flags: []string{"-verify-peer"},
		})
	}
	if config.protocol != quic {
		tests = append(tests, testCase{
			testType: clientTest,
			name:     "ClientAuth-RSA-Client",
			config: Config{
				MaxVersion: VersionTLS12,
				ClientAuth: RequireAnyClientCert,
			},
			shimCertificate: &rsaCertificate,
		})
	}
	tests = append(tests, testCase{
		testType: clientTest,
		name:     "ClientAuth-RSA-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			ClientAuth: RequireAnyClientCert,
		},
		shimCertificate: &rsaCertificate,
	})
	if config.protocol != quic {
		tests = append(tests, testCase{
			testType: clientTest,
			name:     "ClientAuth-ECDSA-Client",
			config: Config{
				MaxVersion: VersionTLS12,
				ClientAuth: RequireAnyClientCert,
			},
			shimCertificate: &ecdsaP256Certificate,
		})
	}
	tests = append(tests, testCase{
		testType: clientTest,
		name:     "ClientAuth-ECDSA-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			ClientAuth: RequireAnyClientCert,
		},
		shimCertificate: &ecdsaP256Certificate,
	})
	if config.protocol != quic {
		tests = append(tests, testCase{
			testType: clientTest,
			name:     "ClientAuth-NoCertificate-OldCallback",
			config: Config{
				MaxVersion: VersionTLS12,
				ClientAuth: RequestClientCert,
			},
			flags: []string{"-use-old-client-cert-callback"},
		})
	}
	tests = append(tests, testCase{
		testType: clientTest,
		name:     "ClientAuth-NoCertificate-OldCallback-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			ClientAuth: RequestClientCert,
		},
		flags: []string{"-use-old-client-cert-callback"},
	})
	if config.protocol != quic {
		tests = append(tests, testCase{
			testType: clientTest,
			name:     "ClientAuth-OldCallback",
			config: Config{
				MaxVersion: VersionTLS12,
				ClientAuth: RequireAnyClientCert,
			},
			shimCertificate: &rsaCertificate,
			flags: []string{
				"-use-old-client-cert-callback",
			},
		})
	}
	tests = append(tests, testCase{
		testType: clientTest,
		name:     "ClientAuth-OldCallback-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			ClientAuth: RequireAnyClientCert,
		},
		shimCertificate: &rsaCertificate,
		flags: []string{
			"-use-old-client-cert-callback",
		},
	})
	if config.protocol != quic {
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "ClientAuth-Server",
			config: Config{
				MaxVersion: VersionTLS12,
				Credential: &rsaCertificate,
			},
			flags: []string{"-require-any-client-certificate"},
		})
	}
	tests = append(tests, testCase{
		testType: serverTest,
		name:     "ClientAuth-Server-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Credential: &rsaCertificate,
		},
		flags: []string{"-require-any-client-certificate"},
	})

	// Test each key exchange on the server side for async keys.
	if config.protocol != quic {
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "Basic-Server-RSA",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_RSA_WITH_AES_128_GCM_SHA256},
			},
			shimCertificate: &rsaCertificate,
		})
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "Basic-Server-ECDHE-RSA",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			},
			shimCertificate: &rsaCertificate,
		})
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "Basic-Server-ECDHE-ECDSA",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256},
			},
			shimCertificate: &ecdsaP256Certificate,
		})
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "Basic-Server-Ed25519",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256},
			},
			shimCertificate: &ed25519Certificate,
			flags: []string{
				"-verify-prefs", strconv.Itoa(int(signatureEd25519)),
			},
		})

		// No session ticket support; server doesn't send NewSessionTicket.
		tests = append(tests, testCase{
			name: "SessionTicketsDisabled-Client",
			config: Config{
				MaxVersion:             VersionTLS12,
				SessionTicketsDisabled: true,
			},
		})
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "SessionTicketsDisabled-Server",
			config: Config{
				MaxVersion:             VersionTLS12,
				SessionTicketsDisabled: true,
			},
		})

		// Skip ServerKeyExchange in PSK key exchange if there's no
		// identity hint.
		tests = append(tests, testCase{
			name: "EmptyPSKHint-Client",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_PSK_WITH_AES_128_CBC_SHA},
				PreSharedKey: []byte("secret"),
			},
			flags: []string{"-psk", "secret"},
		})
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "EmptyPSKHint-Server",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_PSK_WITH_AES_128_CBC_SHA},
				PreSharedKey: []byte("secret"),
			},
			flags: []string{"-psk", "secret"},
		})
	}

	// OCSP stapling tests.
	for _, vers := range allVersions(config.protocol) {
		tests = append(tests, testCase{
			testType: clientTest,
			name:     "OCSPStapling-Client-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
				Credential: rsaCertificate.WithOCSP(testOCSPResponse),
			},
			flags: []string{
				"-enable-ocsp-stapling",
				"-expect-ocsp-response",
				base64FlagValue(testOCSPResponse),
				"-verify-peer",
			},
			resumeSession: true,
		})
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "OCSPStapling-Server-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
			},
			expectations: connectionExpectations{
				peerCertificate: rsaCertificate.WithOCSP(testOCSPResponse),
			},
			shimCertificate: rsaCertificate.WithOCSP(testOCSPResponse),
			resumeSession:   true,
		})

		// The client OCSP callback is an alternate certificate
		// verification callback.
		tests = append(tests, testCase{
			testType: clientTest,
			name:     "ClientOCSPCallback-Pass-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
				Credential: rsaCertificate.WithOCSP(testOCSPResponse),
			},
			flags: []string{
				"-enable-ocsp-stapling",
				"-use-ocsp-callback",
			},
		})
		var expectedLocalError string
		if !config.async {
			// TODO(davidben): Asynchronous fatal alerts are never
			// sent. https://crbug.com/boringssl/130.
			expectedLocalError = "remote error: bad certificate status response"
		}
		tests = append(tests, testCase{
			testType: clientTest,
			name:     "ClientOCSPCallback-Fail-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
				Credential: rsaCertificate.WithOCSP(testOCSPResponse),
			},
			flags: []string{
				"-enable-ocsp-stapling",
				"-use-ocsp-callback",
				"-fail-ocsp-callback",
			},
			shouldFail:         true,
			expectedLocalError: expectedLocalError,
			expectedError:      ":OCSP_CB_ERROR:",
		})
		// The callback still runs if the server does not send an OCSP
		// response.
		tests = append(tests, testCase{
			testType: clientTest,
			name:     "ClientOCSPCallback-FailNoStaple-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
				Credential: &rsaCertificate,
			},
			flags: []string{
				"-enable-ocsp-stapling",
				"-use-ocsp-callback",
				"-fail-ocsp-callback",
			},
			shouldFail:         true,
			expectedLocalError: expectedLocalError,
			expectedError:      ":OCSP_CB_ERROR:",
		})

		// The server OCSP callback is a legacy mechanism for
		// configuring OCSP, used by unreliable server software.
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "ServerOCSPCallback-SetInCallback-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
			},
			shimCertificate: rsaCertificate.WithOCSP(testOCSPResponse),
			expectations: connectionExpectations{
				peerCertificate: rsaCertificate.WithOCSP(testOCSPResponse),
			},
			flags: []string{
				"-use-ocsp-callback",
				"-set-ocsp-in-callback",
			},
			resumeSession: true,
		})

		// The callback may decline OCSP, in which case  we act as if
		// the client did not support it, even if a response was
		// configured.
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "ServerOCSPCallback-Decline-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
			},
			shimCertificate: rsaCertificate.WithOCSP(testOCSPResponse),
			expectations: connectionExpectations{
				// There should be no OCSP response from the peer.
				peerCertificate: &rsaCertificate,
			},
			flags: []string{
				"-use-ocsp-callback",
				"-decline-ocsp-callback",
			},
			resumeSession: true,
		})

		// The callback may also signal an internal error.
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "ServerOCSPCallback-Fail-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
			},
			shimCertificate: rsaCertificate.WithOCSP(testOCSPResponse),
			flags: []string{
				"-use-ocsp-callback",
				"-fail-ocsp-callback",
			},
			shouldFail:    true,
			expectedError: ":OCSP_CB_ERROR:",
		})
	}

	// Certificate verification tests.
	for _, vers := range allVersions(config.protocol) {
		for _, useCustomCallback := range []bool{false, true} {
			for _, testType := range []testType{clientTest, serverTest} {
				suffix := "-Client"
				if testType == serverTest {
					suffix = "-Server"
				}
				suffix += "-" + vers.name
				if useCustomCallback {
					suffix += "-CustomCallback"
				}

				// The custom callback and legacy callback have different default
				// alerts.
				verifyFailLocalError := "remote error: handshake failure"
				if useCustomCallback {
					verifyFailLocalError = "remote error: unknown certificate"
				}

				// We do not reliably send asynchronous fatal alerts. See
				// https://crbug.com/boringssl/130.
				if config.async {
					verifyFailLocalError = ""
				}

				flags := []string{"-verify-peer"}
				if testType == serverTest {
					flags = append(flags, "-require-any-client-certificate")
				}
				if useCustomCallback {
					flags = append(flags, "-use-custom-verify-callback")
				}

				tests = append(tests, testCase{
					testType: testType,
					name:     "CertificateVerificationSucceed" + suffix,
					config: Config{
						MaxVersion: vers.version,
						Credential: &rsaCertificate,
					},
					flags:         append([]string{"-expect-verify-result"}, flags...),
					resumeSession: true,
				})
				tests = append(tests, testCase{
					testType: testType,
					name:     "CertificateVerificationFail" + suffix,
					config: Config{
						MaxVersion: vers.version,
						Credential: &rsaCertificate,
					},
					flags:              append([]string{"-verify-fail"}, flags...),
					shouldFail:         true,
					expectedError:      ":CERTIFICATE_VERIFY_FAILED:",
					expectedLocalError: verifyFailLocalError,
				})
				// Tests that although the verify callback fails on resumption, by default we don't call it.
				tests = append(tests, testCase{
					testType: testType,
					name:     "CertificateVerificationDoesNotFailOnResume" + suffix,
					config: Config{
						MaxVersion: vers.version,
						Credential: &rsaCertificate,
					},
					flags:         append([]string{"-on-resume-verify-fail"}, flags...),
					resumeSession: true,
				})
				if testType == clientTest && useCustomCallback {
					tests = append(tests, testCase{
						testType: testType,
						name:     "CertificateVerificationFailsOnResume" + suffix,
						config: Config{
							MaxVersion: vers.version,
							Credential: &rsaCertificate,
						},
						flags: append([]string{
							"-on-resume-verify-fail",
							"-reverify-on-resume",
						}, flags...),
						resumeSession:      true,
						shouldFail:         true,
						expectedError:      ":CERTIFICATE_VERIFY_FAILED:",
						expectedLocalError: verifyFailLocalError,
					})
					tests = append(tests, testCase{
						testType: testType,
						name:     "CertificateVerificationPassesOnResume" + suffix,
						config: Config{
							MaxVersion: vers.version,
							Credential: &rsaCertificate,
						},
						flags: append([]string{
							"-reverify-on-resume",
						}, flags...),
						resumeSession: true,
					})
					// TODO(crbug.com/381113363): Support 0-RTT in DTLS 1.3.
					if vers.version >= VersionTLS13 && config.protocol != dtls {
						tests = append(tests, testCase{
							testType: testType,
							name:     "EarlyData-RejectTicket-Client-Reverify" + suffix,
							config: Config{
								MaxVersion: vers.version,
							},
							resumeConfig: &Config{
								MaxVersion:             vers.version,
								SessionTicketsDisabled: true,
							},
							resumeSession:           true,
							expectResumeRejected:    true,
							earlyData:               true,
							expectEarlyDataRejected: true,
							flags: append([]string{
								"-reverify-on-resume",
								// Session tickets are disabled, so the runner will not send a ticket.
								"-on-retry-expect-no-session",
							}, flags...),
						})
						tests = append(tests, testCase{
							testType: testType,
							name:     "EarlyData-Reject0RTT-Client-Reverify" + suffix,
							config: Config{
								MaxVersion: vers.version,
								Bugs: ProtocolBugs{
									AlwaysRejectEarlyData: true,
								},
							},
							resumeSession:           true,
							expectResumeRejected:    false,
							earlyData:               true,
							expectEarlyDataRejected: true,
							flags: append([]string{
								"-reverify-on-resume",
							}, flags...),
						})
						tests = append(tests, testCase{
							testType: testType,
							name:     "EarlyData-RejectTicket-Client-ReverifyFails" + suffix,
							config: Config{
								MaxVersion: vers.version,
							},
							resumeConfig: &Config{
								MaxVersion:             vers.version,
								SessionTicketsDisabled: true,
							},
							resumeSession:           true,
							expectResumeRejected:    true,
							earlyData:               true,
							expectEarlyDataRejected: true,
							shouldFail:              true,
							expectedError:           ":CERTIFICATE_VERIFY_FAILED:",
							flags: append([]string{
								"-reverify-on-resume",
								// Session tickets are disabled, so the runner will not send a ticket.
								"-on-retry-expect-no-session",
								"-on-retry-verify-fail",
							}, flags...),
						})
						tests = append(tests, testCase{
							testType: testType,
							name:     "EarlyData-Reject0RTT-Client-ReverifyFails" + suffix,
							config: Config{
								MaxVersion: vers.version,
								Bugs: ProtocolBugs{
									AlwaysRejectEarlyData: true,
								},
							},
							resumeSession:           true,
							expectResumeRejected:    false,
							earlyData:               true,
							expectEarlyDataRejected: true,
							shouldFail:              true,
							expectedError:           ":CERTIFICATE_VERIFY_FAILED:",
							expectedLocalError:      verifyFailLocalError,
							flags: append([]string{
								"-reverify-on-resume",
								"-on-retry-verify-fail",
							}, flags...),
						})
						// This tests that we only call the verify callback once.
						tests = append(tests, testCase{
							testType: testType,
							name:     "EarlyData-Accept0RTT-Client-Reverify" + suffix,
							config: Config{
								MaxVersion: vers.version,
							},
							resumeSession: true,
							earlyData:     true,
							flags: append([]string{
								"-reverify-on-resume",
							}, flags...),
						})
						tests = append(tests, testCase{
							testType: testType,
							name:     "EarlyData-Accept0RTT-Client-ReverifyFails" + suffix,
							config: Config{
								MaxVersion: vers.version,
							},
							resumeSession: true,
							earlyData:     true,
							shouldFail:    true,
							expectedError: ":CERTIFICATE_VERIFY_FAILED:",
							// We do not set expectedLocalError here because the shim rejects
							// the connection without an alert.
							flags: append([]string{
								"-reverify-on-resume",
								"-on-resume-verify-fail",
							}, flags...),
						})
					}
				}
			}
		}

		// By default, the client is in a soft fail mode where the peer
		// certificate is verified but failures are non-fatal.
		tests = append(tests, testCase{
			testType: clientTest,
			name:     "CertificateVerificationSoftFail-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
				Credential: &rsaCertificate,
			},
			flags: []string{
				"-verify-fail",
				"-expect-verify-result",
			},
			resumeSession: true,
		})
	}

	tests = append(tests, testCase{
		name:               "ShimSendAlert",
		flags:              []string{"-send-alert"},
		shimWritesFirst:    true,
		shouldFail:         true,
		expectedLocalError: "remote error: decompression failure",
	})

	if config.protocol == tls {
		tests = append(tests, testCase{
			name: "Renegotiate-Client",
			config: Config{
				MaxVersion: VersionTLS12,
			},
			renegotiate: 1,
			flags: []string{
				"-renegotiate-freely",
				"-expect-total-renegotiations", "1",
			},
		})

		tests = append(tests, testCase{
			name: "Renegotiate-Client-Explicit",
			config: Config{
				MaxVersion: VersionTLS12,
			},
			renegotiate: 1,
			flags: []string{
				"-renegotiate-explicit",
				"-expect-total-renegotiations", "1",
			},
		})

		halfHelloRequestError := ":UNEXPECTED_RECORD:"
		if config.packHandshake {
			// If the HelloRequest is sent in the same record as the server Finished,
			// BoringSSL rejects it before the handshake completes.
			halfHelloRequestError = ":EXCESS_HANDSHAKE_DATA:"
		}
		tests = append(tests, testCase{
			name: "SendHalfHelloRequest",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					PackHelloRequestWithFinished: config.packHandshake,
				},
			},
			sendHalfHelloRequest: true,
			flags:                []string{"-renegotiate-ignore"},
			shouldFail:           true,
			expectedError:        halfHelloRequestError,
		})

		// NPN on client and server; results in post-ChangeCipherSpec message.
		tests = append(tests, testCase{
			name: "NPN-Client",
			config: Config{
				MaxVersion: VersionTLS12,
				NextProtos: []string{"foo"},
			},
			flags:         []string{"-select-next-proto", "foo"},
			resumeSession: true,
			expectations: connectionExpectations{
				nextProto:     "foo",
				nextProtoType: npn,
			},
		})
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "NPN-Server",
			config: Config{
				MaxVersion: VersionTLS12,
				NextProtos: []string{"bar"},
			},
			flags: []string{
				"-advertise-npn", "\x03foo\x03bar\x03baz",
				"-expect-next-proto", "bar",
			},
			resumeSession: true,
			expectations: connectionExpectations{
				nextProto:     "bar",
				nextProtoType: npn,
			},
		})

		// The client may select no protocol after seeing the server list.
		tests = append(tests, testCase{
			name: "NPN-Client-ClientSelectEmpty",
			config: Config{
				MaxVersion: VersionTLS12,
				NextProtos: []string{"foo"},
			},
			flags:         []string{"-select-empty-next-proto"},
			resumeSession: true,
			expectations: connectionExpectations{
				noNextProto:   true,
				nextProtoType: npn,
			},
		})
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "NPN-Server-ClientSelectEmpty",
			config: Config{
				MaxVersion:          VersionTLS12,
				NextProtos:          []string{"no-match"},
				NoFallbackNextProto: true,
			},
			flags: []string{
				"-advertise-npn", "\x03foo\x03bar\x03baz",
				"-expect-no-next-proto",
			},
			resumeSession: true,
			expectations: connectionExpectations{
				noNextProto:   true,
				nextProtoType: npn,
			},
		})

		// The server may negotiate NPN, despite offering no protocols. In this
		// case, the server must still be prepared for the client to select a
		// fallback protocol.
		tests = append(tests, testCase{
			name: "NPN-Client-ServerAdvertiseEmpty",
			config: Config{
				MaxVersion:               VersionTLS12,
				NegotiateNPNWithNoProtos: true,
			},
			flags:         []string{"-select-next-proto", "foo"},
			resumeSession: true,
			expectations: connectionExpectations{
				nextProto:     "foo",
				nextProtoType: npn,
			},
		})
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "NPN-Server-ServerAdvertiseEmpty",
			config: Config{
				MaxVersion: VersionTLS12,
				NextProtos: []string{"foo"},
			},
			flags: []string{
				"-advertise-empty-npn",
				"-expect-next-proto", "foo",
			},
			resumeSession: true,
			expectations: connectionExpectations{
				nextProto:     "foo",
				nextProtoType: npn,
			},
		})

		// Client does False Start and negotiates NPN.
		tests = append(tests, testCase{
			name: "FalseStart",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
				NextProtos:   []string{"foo"},
				Bugs: ProtocolBugs{
					ExpectFalseStart: true,
				},
			},
			flags: []string{
				"-false-start",
				"-select-next-proto", "foo",
			},
			shimWritesFirst: true,
			resumeSession:   true,
		})

		// Client does False Start and negotiates ALPN.
		tests = append(tests, testCase{
			name: "FalseStart-ALPN",
			config: Config{
				MaxVersion:   VersionTLS12,
				CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
				NextProtos:   []string{"foo"},
				Bugs: ProtocolBugs{
					ExpectFalseStart: true,
				},
			},
			flags: []string{
				"-false-start",
				"-advertise-alpn", "\x03foo",
				"-expect-alpn", "foo",
			},
			shimWritesFirst: true,
			resumeSession:   true,
		})

		// False Start without session tickets.
		tests = append(tests, testCase{
			name: "FalseStart-SessionTicketsDisabled",
			config: Config{
				MaxVersion:             VersionTLS12,
				CipherSuites:           []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
				NextProtos:             []string{"foo"},
				SessionTicketsDisabled: true,
				Bugs: ProtocolBugs{
					ExpectFalseStart: true,
				},
			},
			flags: []string{
				"-false-start",
				"-select-next-proto", "foo",
			},
			shimWritesFirst: true,
		})

		// Server parses a V2ClientHello. Test different lengths for the
		// challenge field.
		for _, challengeLength := range []int{16, 31, 32, 33, 48} {
			tests = append(tests, testCase{
				testType: serverTest,
				name:     fmt.Sprintf("SendV2ClientHello-%d", challengeLength),
				config: Config{
					// Choose a cipher suite that does not involve
					// elliptic curves, so no extensions are
					// involved.
					MaxVersion:   VersionTLS12,
					CipherSuites: []uint16{TLS_RSA_WITH_AES_128_CBC_SHA},
					Bugs: ProtocolBugs{
						SendV2ClientHello:            true,
						V2ClientHelloChallengeLength: challengeLength,
					},
				},
				flags: []string{
					"-expect-msg-callback",
					`read v2clienthello
write hs 2
write hs 11
write hs 14
read hs 16
read ccs
read hs 20
write ccs
write hs 20
read alert 1 0
`,
				},
			})
		}

		// Channel ID and NPN at the same time, to ensure their relative
		// ordering is correct.
		tests = append(tests, testCase{
			name: "ChannelID-NPN-Client",
			config: Config{
				MaxVersion:       VersionTLS12,
				RequestChannelID: true,
				NextProtos:       []string{"foo"},
			},
			flags: []string{
				"-send-channel-id", channelIDKeyPath,
				"-select-next-proto", "foo",
			},
			resumeSession: true,
			expectations: connectionExpectations{
				channelID:     true,
				nextProto:     "foo",
				nextProtoType: npn,
			},
		})
		tests = append(tests, testCase{
			testType: serverTest,
			name:     "ChannelID-NPN-Server",
			config: Config{
				MaxVersion: VersionTLS12,
				ChannelID:  &channelIDKey,
				NextProtos: []string{"bar"},
			},
			flags: []string{
				"-expect-channel-id",
				base64FlagValue(channelIDBytes),
				"-advertise-npn", "\x03foo\x03bar\x03baz",
				"-expect-next-proto", "bar",
			},
			resumeSession: true,
			expectations: connectionExpectations{
				channelID:     true,
				nextProto:     "bar",
				nextProtoType: npn,
			},
		})

		// Bidirectional shutdown with the runner initiating.
		tests = append(tests, testCase{
			name: "Shutdown-Runner",
			config: Config{
				Bugs: ProtocolBugs{
					ExpectCloseNotify: true,
				},
			},
			flags: []string{"-check-close-notify"},
		})
	}
	if config.protocol != dtls {
		// Test Channel ID
		for _, ver := range allVersions(config.protocol) {
			if ver.version < VersionTLS10 {
				continue
			}
			// Client sends a Channel ID.
			tests = append(tests, testCase{
				name: "ChannelID-Client-" + ver.name,
				config: Config{
					MaxVersion:       ver.version,
					RequestChannelID: true,
				},
				flags:         []string{"-send-channel-id", channelIDKeyPath},
				resumeSession: true,
				expectations: connectionExpectations{
					channelID: true,
				},
			})

			// Server accepts a Channel ID.
			tests = append(tests, testCase{
				testType: serverTest,
				name:     "ChannelID-Server-" + ver.name,
				config: Config{
					MaxVersion: ver.version,
					ChannelID:  &channelIDKey,
				},
				flags: []string{
					"-expect-channel-id",
					base64FlagValue(channelIDBytes),
				},
				resumeSession: true,
				expectations: connectionExpectations{
					channelID: true,
				},
			})

			tests = append(tests, testCase{
				testType: serverTest,
				name:     "InvalidChannelIDSignature-" + ver.name,
				config: Config{
					MaxVersion: ver.version,
					ChannelID:  &channelIDKey,
					Bugs: ProtocolBugs{
						InvalidChannelIDSignature: true,
					},
				},
				flags:         []string{"-enable-channel-id"},
				shouldFail:    true,
				expectedError: ":CHANNEL_ID_SIGNATURE_INVALID:",
			})

			if ver.version < VersionTLS13 {
				// Channel ID requires ECDHE ciphers.
				tests = append(tests, testCase{
					testType: serverTest,
					name:     "ChannelID-NoECDHE-" + ver.name,
					config: Config{
						MaxVersion:   ver.version,
						CipherSuites: []uint16{TLS_RSA_WITH_AES_128_CBC_SHA},
						ChannelID:    &channelIDKey,
					},
					expectations: connectionExpectations{
						channelID: false,
					},
					flags: []string{"-enable-channel-id"},
				})

				// Sanity-check setting expectations.channelID false works.
				tests = append(tests, testCase{
					testType: serverTest,
					name:     "ChannelID-ECDHE-" + ver.name,
					config: Config{
						MaxVersion:   ver.version,
						CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA},
						ChannelID:    &channelIDKey,
					},
					expectations: connectionExpectations{
						channelID: false,
					},
					flags:              []string{"-enable-channel-id"},
					shouldFail:         true,
					expectedLocalError: "channel ID unexpectedly negotiated",
				})
			}
		}

		if !config.implicitHandshake {
			// Bidirectional shutdown with the shim initiating. The runner,
			// in the meantime, sends garbage before the close_notify which
			// the shim must ignore. This test is disabled under implicit
			// handshake tests because the shim never reads or writes.

			// Tests that require checking for a close notify alert don't work with
			// QUIC because alerts are handled outside of the TLS stack in QUIC.
			if config.protocol != quic {
				tests = append(tests, testCase{
					name: "Shutdown-Shim",
					config: Config{
						MaxVersion: VersionTLS12,
						Bugs: ProtocolBugs{
							ExpectCloseNotify: true,
						},
					},
					shimShutsDown:     true,
					sendEmptyRecords:  1,
					sendWarningAlerts: 1,
					flags:             []string{"-check-close-notify"},
				})

				// The shim should reject unexpected application data
				// when shutting down.
				tests = append(tests, testCase{
					name: "Shutdown-Shim-ApplicationData",
					config: Config{
						MaxVersion: VersionTLS12,
						Bugs: ProtocolBugs{
							ExpectCloseNotify: true,
						},
					},
					shimShutsDown:     true,
					messageCount:      1,
					sendEmptyRecords:  1,
					sendWarningAlerts: 1,
					flags:             []string{"-check-close-notify"},
					shouldFail:        true,
					expectedError:     ":APPLICATION_DATA_ON_SHUTDOWN:",
				})

				// Test that SSL_shutdown still processes KeyUpdate.
				tests = append(tests, testCase{
					name: "Shutdown-Shim-KeyUpdate",
					config: Config{
						MinVersion: VersionTLS13,
						MaxVersion: VersionTLS13,
						Bugs: ProtocolBugs{
							ExpectCloseNotify: true,
						},
					},
					shimShutsDown:    true,
					sendKeyUpdates:   1,
					keyUpdateRequest: keyUpdateRequested,
					flags:            []string{"-check-close-notify"},
				})

				// Test that SSL_shutdown processes HelloRequest
				// correctly.
				tests = append(tests, testCase{
					name: "Shutdown-Shim-HelloRequest-Ignore",
					config: Config{
						MinVersion: VersionTLS12,
						MaxVersion: VersionTLS12,
						Bugs: ProtocolBugs{
							SendHelloRequestBeforeEveryAppDataRecord: true,
							ExpectCloseNotify:                        true,
						},
					},
					shimShutsDown: true,
					flags: []string{
						"-renegotiate-ignore",
						"-check-close-notify",
					},
				})
				tests = append(tests, testCase{
					name: "Shutdown-Shim-HelloRequest-Reject",
					config: Config{
						MinVersion: VersionTLS12,
						MaxVersion: VersionTLS12,
						Bugs: ProtocolBugs{
							ExpectCloseNotify: true,
						},
					},
					shimShutsDown: true,
					renegotiate:   1,
					shouldFail:    true,
					expectedError: ":NO_RENEGOTIATION:",
					flags:         []string{"-check-close-notify"},
				})
				tests = append(tests, testCase{
					name: "Shutdown-Shim-HelloRequest-CannotHandshake",
					config: Config{
						MinVersion: VersionTLS12,
						MaxVersion: VersionTLS12,
						Bugs: ProtocolBugs{
							ExpectCloseNotify: true,
						},
					},
					shimShutsDown: true,
					renegotiate:   1,
					shouldFail:    true,
					expectedError: ":NO_RENEGOTIATION:",
					flags: []string{
						"-check-close-notify",
						"-renegotiate-freely",
					},
				})

				tests = append(tests, testCase{
					testType: serverTest,
					name:     "Shutdown-Shim-Renegotiate-Server-Forbidden",
					config: Config{
						MaxVersion: VersionTLS12,
						Bugs: ProtocolBugs{
							ExpectCloseNotify: true,
						},
					},
					shimShutsDown: true,
					renegotiate:   1,
					shouldFail:    true,
					expectedError: ":NO_RENEGOTIATION:",
					flags: []string{
						"-check-close-notify",
					},
				})
			}
		}
	}
	if config.protocol == dtls {
		tests = append(tests, testCase{
			name: "SkipHelloVerifyRequest",
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					SkipHelloVerifyRequest: true,
				},
			},
		})
		tests = append(tests, testCase{
			name: "DTLS13-HelloVerifyRequest",
			config: Config{
				MinVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					ForceHelloVerifyRequest: true,
				},
			},
			shouldFail:    true,
			expectedError: ":INVALID_MESSAGE:",
		})
		tests = append(tests, testCase{
			name: "DTLS13-HelloVerifyRequestEmptyCookie",
			config: Config{
				MinVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					ForceHelloVerifyRequest:       true,
					EmptyHelloVerifyRequestCookie: true,
				},
			},
			shouldFail:    true,
			expectedError: ":INVALID_MESSAGE:",
		})
	}

	for _, test := range tests {
		test.protocol = config.protocol
		test.name += "-" + config.protocol.String()
		if config.async {
			test.name += "-Async"
			test.flags = append(test.flags, "-async")
		} else {
			test.name += "-Sync"
		}
		if config.splitHandshake {
			test.name += "-SplitHandshakeRecords"
			test.config.Bugs.MaxHandshakeRecordLength = 1
			if config.protocol == dtls {
				test.config.Bugs.MaxPacketLength = 256
				test.flags = append(test.flags, "-mtu", "256")
			}
		}
		if config.packHandshake {
			test.name += "-PackHandshake"
			if config.protocol == dtls {
				test.config.Bugs.MaxHandshakeRecordLength = 2
				test.config.Bugs.PackHandshakeFragments = 20
				test.config.Bugs.PackHandshakeRecords = 1500
				test.config.Bugs.PackAppDataWithHandshake = true
			} else {
				test.config.Bugs.PackHandshakeFlight = true
			}
		}
		if config.implicitHandshake {
			test.name += "-ImplicitHandshake"
			test.flags = append(test.flags, "-implicit-handshake")
		}
		testCases = append(testCases, test)
	}
}

func addDDoSCallbackTests() {
	// DDoS callback.
	for _, resume := range []bool{false, true} {
		suffix := "Resume"
		if resume {
			suffix = "No" + suffix
		}

		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "Server-DDoS-OK-" + suffix,
			config: Config{
				MaxVersion: VersionTLS12,
			},
			flags:         []string{"-install-ddos-callback"},
			resumeSession: resume,
		})
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "Server-DDoS-OK-" + suffix + "-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
			},
			flags:         []string{"-install-ddos-callback"},
			resumeSession: resume,
		})

		failFlag := "-fail-ddos-callback"
		if resume {
			failFlag = "-on-resume-fail-ddos-callback"
		}
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "Server-DDoS-Reject-" + suffix,
			config: Config{
				MaxVersion: VersionTLS12,
			},
			flags:              []string{"-install-ddos-callback", failFlag},
			resumeSession:      resume,
			shouldFail:         true,
			expectedError:      ":CONNECTION_REJECTED:",
			expectedLocalError: "remote error: internal error",
		})
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "Server-DDoS-Reject-" + suffix + "-TLS13",
			config: Config{
				MaxVersion: VersionTLS13,
			},
			flags:              []string{"-install-ddos-callback", failFlag},
			resumeSession:      resume,
			shouldFail:         true,
			expectedError:      ":CONNECTION_REJECTED:",
			expectedLocalError: "remote error: internal error",
		})
	}
}

func addVersionNegotiationTests() {
	for _, protocol := range []protocol{tls, dtls, quic} {
		for _, shimVers := range allVersions(protocol) {
			// Assemble flags to disable all newer versions on the shim.
			var flags []string
			for _, vers := range allVersions(protocol) {
				if vers.version > shimVers.version {
					flags = append(flags, vers.excludeFlag)
				}
			}

			flags2 := []string{"-max-version", shimVers.shimFlag(protocol)}

			// Test configuring the runner's maximum version.
			for _, runnerVers := range allVersions(protocol) {
				expectedVersion := shimVers.version
				if runnerVers.version < shimVers.version {
					expectedVersion = runnerVers.version
				}

				suffix := shimVers.name + "-" + runnerVers.name
				suffix += "-" + protocol.String()

				// Determine the expected initial record-layer versions.
				clientVers := shimVers.version
				if clientVers > VersionTLS10 {
					clientVers = VersionTLS10
				}
				clientVers = recordVersionToWire(clientVers, protocol)
				serverVers := expectedVersion
				if expectedVersion >= VersionTLS13 {
					serverVers = VersionTLS12
				}
				serverVers = recordVersionToWire(serverVers, protocol)

				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: clientTest,
					name:     "VersionNegotiation-Client-" + suffix,
					config: Config{
						MaxVersion: runnerVers.version,
						Bugs: ProtocolBugs{
							ExpectInitialRecordVersion: clientVers,
						},
					},
					flags: flags,
					expectations: connectionExpectations{
						version: expectedVersion,
					},
					// The version name check does not recognize the
					// |excludeFlag| construction in |flags|.
					skipVersionNameCheck: true,
				})
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: clientTest,
					name:     "VersionNegotiation-Client2-" + suffix,
					config: Config{
						MaxVersion: runnerVers.version,
						Bugs: ProtocolBugs{
							ExpectInitialRecordVersion: clientVers,
						},
					},
					flags: flags2,
					expectations: connectionExpectations{
						version: expectedVersion,
					},
				})

				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "VersionNegotiation-Server-" + suffix,
					config: Config{
						MaxVersion: runnerVers.version,
						Bugs: ProtocolBugs{
							ExpectInitialRecordVersion: serverVers,
						},
					},
					flags: flags,
					expectations: connectionExpectations{
						version: expectedVersion,
					},
					// The version name check does not recognize the
					// |excludeFlag| construction in |flags|.
					skipVersionNameCheck: true,
				})
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "VersionNegotiation-Server2-" + suffix,
					config: Config{
						MaxVersion: runnerVers.version,
						Bugs: ProtocolBugs{
							ExpectInitialRecordVersion: serverVers,
						},
					},
					flags: flags2,
					expectations: connectionExpectations{
						version: expectedVersion,
					},
				})
			}
		}
	}

	// Test the version extension at all versions.
	for _, protocol := range []protocol{tls, dtls, quic} {
		for _, vers := range allVersions(protocol) {
			suffix := vers.name + "-" + protocol.String()

			testCases = append(testCases, testCase{
				protocol: protocol,
				testType: serverTest,
				name:     "VersionNegotiationExtension-" + suffix,
				config: Config{
					Bugs: ProtocolBugs{
						SendSupportedVersions:      []uint16{0x1111, vers.wire(protocol), 0x2222},
						IgnoreTLS13DowngradeRandom: true,
					},
				},
				expectations: connectionExpectations{
					version: vers.version,
				},
			})
		}
	}

	// If all versions are unknown, negotiation fails.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "NoSupportedVersions",
		config: Config{
			Bugs: ProtocolBugs{
				SendSupportedVersions: []uint16{0x1111},
			},
		},
		shouldFail:    true,
		expectedError: ":UNSUPPORTED_PROTOCOL:",
	})
	testCases = append(testCases, testCase{
		protocol: dtls,
		testType: serverTest,
		name:     "NoSupportedVersions-DTLS",
		config: Config{
			Bugs: ProtocolBugs{
				SendSupportedVersions: []uint16{0x1111},
			},
		},
		shouldFail:    true,
		expectedError: ":UNSUPPORTED_PROTOCOL:",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ClientHelloVersionTooHigh",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendClientVersion:          0x0304,
				OmitSupportedVersions:      true,
				IgnoreTLS13DowngradeRandom: true,
			},
		},
		expectations: connectionExpectations{
			version: VersionTLS12,
		},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ConflictingVersionNegotiation",
		config: Config{
			Bugs: ProtocolBugs{
				SendClientVersion:          VersionTLS12,
				SendSupportedVersions:      []uint16{VersionTLS11},
				IgnoreTLS13DowngradeRandom: true,
			},
		},
		// The extension takes precedence over the ClientHello version.
		expectations: connectionExpectations{
			version: VersionTLS11,
		},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ConflictingVersionNegotiation-2",
		config: Config{
			Bugs: ProtocolBugs{
				SendClientVersion:          VersionTLS11,
				SendSupportedVersions:      []uint16{VersionTLS12},
				IgnoreTLS13DowngradeRandom: true,
			},
		},
		// The extension takes precedence over the ClientHello version.
		expectations: connectionExpectations{
			version: VersionTLS12,
		},
	})

	// Test that TLS 1.2 isn't negotiated by the supported_versions extension in
	// the ServerHello.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "SupportedVersionSelection-TLS12",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SendServerSupportedVersionExtension: VersionTLS12,
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_EXTENSION:",
	})

	// Test that the maximum version is selected regardless of the
	// client-sent order.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "IgnoreClientVersionOrder",
		config: Config{
			Bugs: ProtocolBugs{
				SendSupportedVersions: []uint16{VersionTLS12, VersionTLS13},
			},
		},
		expectations: connectionExpectations{
			version: VersionTLS13,
		},
	})

	// Test for version tolerance.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "MinorVersionTolerance",
		config: Config{
			Bugs: ProtocolBugs{
				SendClientVersion:          0x03ff,
				OmitSupportedVersions:      true,
				IgnoreTLS13DowngradeRandom: true,
			},
		},
		expectations: connectionExpectations{
			version: VersionTLS12,
		},
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "MajorVersionTolerance",
		config: Config{
			Bugs: ProtocolBugs{
				SendClientVersion:          0x0400,
				OmitSupportedVersions:      true,
				IgnoreTLS13DowngradeRandom: true,
			},
		},
		// TLS 1.3 must be negotiated with the supported_versions
		// extension, not ClientHello.version.
		expectations: connectionExpectations{
			version: VersionTLS12,
		},
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "VersionTolerance-TLS13",
		config: Config{
			Bugs: ProtocolBugs{
				// Although TLS 1.3 does not use
				// ClientHello.version, it still tolerates high
				// values there.
				SendClientVersion: 0x0400,
			},
		},
		expectations: connectionExpectations{
			version: VersionTLS13,
		},
	})

	testCases = append(testCases, testCase{
		protocol: dtls,
		testType: serverTest,
		name:     "MinorVersionTolerance-DTLS",
		config: Config{
			Bugs: ProtocolBugs{
				SendClientVersion:          0xfe00,
				OmitSupportedVersions:      true,
				IgnoreTLS13DowngradeRandom: true,
			},
		},
		expectations: connectionExpectations{
			version: VersionTLS12,
		},
	})
	testCases = append(testCases, testCase{
		protocol: dtls,
		testType: serverTest,
		name:     "MajorVersionTolerance-DTLS",
		config: Config{
			Bugs: ProtocolBugs{
				SendClientVersion:          0xfdff,
				OmitSupportedVersions:      true,
				IgnoreTLS13DowngradeRandom: true,
			},
		},
		expectations: connectionExpectations{
			version: VersionTLS12,
		},
	})

	// Test that versions below 3.0 are rejected.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "VersionTooLow",
		config: Config{
			Bugs: ProtocolBugs{
				SendClientVersion:     0x0200,
				OmitSupportedVersions: true,
			},
		},
		shouldFail:    true,
		expectedError: ":UNSUPPORTED_PROTOCOL:",
	})
	testCases = append(testCases, testCase{
		protocol: dtls,
		testType: serverTest,
		name:     "VersionTooLow-DTLS",
		config: Config{
			Bugs: ProtocolBugs{
				SendClientVersion:     0xffff,
				OmitSupportedVersions: true,
			},
		},
		shouldFail:    true,
		expectedError: ":UNSUPPORTED_PROTOCOL:",
	})

	testCases = append(testCases, testCase{
		name: "ServerBogusVersion",
		config: Config{
			Bugs: ProtocolBugs{
				SendServerHelloVersion: 0x1234,
			},
		},
		shouldFail:    true,
		expectedError: ":UNSUPPORTED_PROTOCOL:",
	})

	// Test TLS 1.3's downgrade signal.
	for _, protocol := range []protocol{tls, dtls} {
		for _, vers := range allVersions(protocol) {
			if vers.version >= VersionTLS13 {
				continue
			}
			clientShimError := "tls: downgrade from TLS 1.3 detected"
			if vers.version < VersionTLS12 {
				clientShimError = "tls: downgrade from TLS 1.2 detected"
			}
			// for _, test := range downgradeTests {
			// The client should enforce the downgrade sentinel.
			testCases = append(testCases, testCase{
				protocol: protocol,
				name:     "Downgrade-" + vers.name + "-Client-" + protocol.String(),
				config: Config{
					Bugs: ProtocolBugs{
						NegotiateVersion: vers.wire(protocol),
					},
				},
				expectations: connectionExpectations{
					version: vers.version,
				},
				shouldFail:         true,
				expectedError:      ":TLS13_DOWNGRADE:",
				expectedLocalError: "remote error: illegal parameter",
			})

			// The server should emit the downgrade signal.
			testCases = append(testCases, testCase{
				protocol: protocol,
				testType: serverTest,
				name:     "Downgrade-" + vers.name + "-Server-" + protocol.String(),
				config: Config{
					Bugs: ProtocolBugs{
						SendSupportedVersions: []uint16{vers.wire(protocol)},
					},
				},
				expectations: connectionExpectations{
					version: vers.version,
				},
				shouldFail:         true,
				expectedLocalError: clientShimError,
			})
		}
	}

	// SSL 3.0 support has been removed. Test that the shim does not
	// support it.
	testCases = append(testCases, testCase{
		name: "NoSSL3-Client",
		config: Config{
			MinVersion: VersionSSL30,
			MaxVersion: VersionSSL30,
		},
		shouldFail:         true,
		expectedLocalError: "tls: client did not offer any supported protocol versions",
	})
	testCases = append(testCases, testCase{
		name: "NoSSL3-Client-Unsolicited",
		config: Config{
			MinVersion: VersionSSL30,
			MaxVersion: VersionSSL30,
			Bugs: ProtocolBugs{
				// The above test asserts the client does not
				// offer SSL 3.0 in the supported_versions
				// list. Additionally assert that it rejects an
				// unsolicited SSL 3.0 ServerHello.
				NegotiateVersion: VersionSSL30,
			},
		},
		shouldFail:         true,
		expectedError:      ":UNSUPPORTED_PROTOCOL:",
		expectedLocalError: "remote error: protocol version not supported",
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "NoSSL3-Server",
		config: Config{
			MinVersion: VersionSSL30,
			MaxVersion: VersionSSL30,
		},
		shouldFail:         true,
		expectedError:      ":UNSUPPORTED_PROTOCOL:",
		expectedLocalError: "remote error: protocol version not supported",
	})
}

func addMinimumVersionTests() {
	for _, protocol := range []protocol{tls, dtls, quic} {
		for _, shimVers := range allVersions(protocol) {
			// Assemble flags to disable all older versions on the shim.
			var flags []string
			for _, vers := range allVersions(protocol) {
				if vers.version < shimVers.version {
					flags = append(flags, vers.excludeFlag)
				}
			}

			flags2 := []string{"-min-version", shimVers.shimFlag(protocol)}

			for _, runnerVers := range allVersions(protocol) {
				suffix := shimVers.name + "-" + runnerVers.name
				suffix += "-" + protocol.String()

				var expectedVersion uint16
				var shouldFail bool
				var expectedError, expectedLocalError string
				if runnerVers.version >= shimVers.version {
					expectedVersion = runnerVers.version
				} else {
					shouldFail = true
					expectedError = ":UNSUPPORTED_PROTOCOL:"
					expectedLocalError = "remote error: protocol version not supported"
				}

				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: clientTest,
					name:     "MinimumVersion-Client-" + suffix,
					config: Config{
						MaxVersion: runnerVers.version,
						Bugs: ProtocolBugs{
							// Ensure the server does not decline to
							// select a version (versions extension) or
							// cipher (some ciphers depend on versions).
							NegotiateVersion:            runnerVers.wire(protocol),
							IgnorePeerCipherPreferences: shouldFail,
						},
					},
					flags: flags,
					expectations: connectionExpectations{
						version: expectedVersion,
					},
					shouldFail:         shouldFail,
					expectedError:      expectedError,
					expectedLocalError: expectedLocalError,
					// The version name check does not recognize the
					// |excludeFlag| construction in |flags|.
					skipVersionNameCheck: true,
				})
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: clientTest,
					name:     "MinimumVersion-Client2-" + suffix,
					config: Config{
						MaxVersion: runnerVers.version,
						Bugs: ProtocolBugs{
							// Ensure the server does not decline to
							// select a version (versions extension) or
							// cipher (some ciphers depend on versions).
							NegotiateVersion:            runnerVers.wire(protocol),
							IgnorePeerCipherPreferences: shouldFail,
						},
					},
					flags: flags2,
					expectations: connectionExpectations{
						version: expectedVersion,
					},
					shouldFail:         shouldFail,
					expectedError:      expectedError,
					expectedLocalError: expectedLocalError,
				})

				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "MinimumVersion-Server-" + suffix,
					config: Config{
						MaxVersion: runnerVers.version,
					},
					flags: flags,
					expectations: connectionExpectations{
						version: expectedVersion,
					},
					shouldFail:         shouldFail,
					expectedError:      expectedError,
					expectedLocalError: expectedLocalError,
					// The version name check does not recognize the
					// |excludeFlag| construction in |flags|.
					skipVersionNameCheck: true,
				})
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "MinimumVersion-Server2-" + suffix,
					config: Config{
						MaxVersion: runnerVers.version,
					},
					flags: flags2,
					expectations: connectionExpectations{
						version: expectedVersion,
					},
					shouldFail:         shouldFail,
					expectedError:      expectedError,
					expectedLocalError: expectedLocalError,
				})
			}
		}
	}
}

func addExtensionTests() {
	exampleCertificate := generateSingleCertChain(&x509.Certificate{
		SerialNumber: big.NewInt(57005),
		Subject: pkix.Name{
			CommonName: "test cert",
		},
		NotBefore:             time.Now().Add(-time.Hour),
		NotAfter:              time.Now().Add(time.Hour),
		DNSNames:              []string{"example.com"},
		IsCA:                  true,
		BasicConstraintsValid: true,
	}, &ecdsaP256Key)

	// Repeat extensions tests at all versions.
	for _, protocol := range []protocol{tls, dtls, quic} {
		for _, ver := range allVersions(protocol) {
			suffix := fmt.Sprintf("%s-%s", protocol.String(), ver.name)

			// Test that duplicate extensions are rejected.
			testCases = append(testCases, testCase{
				protocol: protocol,
				testType: clientTest,
				name:     "DuplicateExtensionClient-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					Bugs: ProtocolBugs{
						DuplicateExtension: true,
					},
				},
				shouldFail:         true,
				expectedLocalError: "remote error: error decoding message",
			})
			testCases = append(testCases, testCase{
				protocol: protocol,
				testType: serverTest,
				name:     "DuplicateExtensionServer-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					Bugs: ProtocolBugs{
						DuplicateExtension: true,
					},
				},
				shouldFail:         true,
				expectedLocalError: "remote error: error decoding message",
			})

			// Test SNI.
			testCases = append(testCases, testCase{
				protocol: protocol,
				testType: clientTest,
				name:     "ServerNameExtensionClient-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					Bugs: ProtocolBugs{
						ExpectServerName: "example.com",
					},
					Credential: &exampleCertificate,
				},
				flags: []string{"-host-name", "example.com"},
			})
			testCases = append(testCases, testCase{
				protocol: protocol,
				testType: clientTest,
				name:     "ServerNameExtensionClientMismatch-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					Bugs: ProtocolBugs{
						ExpectServerName: "mismatch.com",
					},
				},
				flags:              []string{"-host-name", "example.com"},
				shouldFail:         true,
				expectedLocalError: "tls: unexpected server name",
			})
			testCases = append(testCases, testCase{
				protocol: protocol,
				testType: clientTest,
				name:     "ServerNameExtensionClientMissing-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					Bugs: ProtocolBugs{
						ExpectServerName: "missing.com",
					},
				},
				shouldFail:         true,
				expectedLocalError: "tls: unexpected server name",
			})
			testCases = append(testCases, testCase{
				protocol: protocol,
				testType: clientTest,
				name:     "TolerateServerNameAck-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					Bugs: ProtocolBugs{
						SendServerNameAck: true,
					},
					Credential: &exampleCertificate,
				},
				flags:         []string{"-host-name", "example.com"},
				resumeSession: true,
			})
			testCases = append(testCases, testCase{
				protocol: protocol,
				testType: clientTest,
				name:     "UnsolicitedServerNameAck-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					Bugs: ProtocolBugs{
						SendServerNameAck: true,
					},
				},
				shouldFail:         true,
				expectedError:      ":UNEXPECTED_EXTENSION:",
				expectedLocalError: "remote error: unsupported extension",
			})
			testCases = append(testCases, testCase{
				protocol: protocol,
				testType: serverTest,
				name:     "ServerNameExtensionServer-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					ServerName: "example.com",
				},
				flags:         []string{"-expect-server-name", "example.com"},
				resumeSession: true,
			})

			// Test ALPN.
			testCases = append(testCases, testCase{
				protocol:           protocol,
				testType:           clientTest,
				skipQUICALPNConfig: true,
				name:               "ALPNClient-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					NextProtos: []string{"foo"},
				},
				flags: []string{
					"-advertise-alpn", "\x03foo\x03bar\x03baz",
					"-expect-alpn", "foo",
				},
				expectations: connectionExpectations{
					nextProto:     "foo",
					nextProtoType: alpn,
				},
				resumeSession: true,
			})
			testCases = append(testCases, testCase{
				protocol:           protocol,
				testType:           clientTest,
				skipQUICALPNConfig: true,
				name:               "ALPNClient-RejectUnknown-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					Bugs: ProtocolBugs{
						SendALPN: "baz",
					},
				},
				flags: []string{
					"-advertise-alpn", "\x03foo\x03bar",
				},
				shouldFail:         true,
				expectedError:      ":INVALID_ALPN_PROTOCOL:",
				expectedLocalError: "remote error: illegal parameter",
			})
			testCases = append(testCases, testCase{
				protocol:           protocol,
				testType:           clientTest,
				skipQUICALPNConfig: true,
				name:               "ALPNClient-AllowUnknown-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					Bugs: ProtocolBugs{
						SendALPN: "baz",
					},
				},
				flags: []string{
					"-advertise-alpn", "\x03foo\x03bar",
					"-allow-unknown-alpn-protos",
					"-expect-alpn", "baz",
				},
			})
			testCases = append(testCases, testCase{
				protocol:           protocol,
				testType:           serverTest,
				skipQUICALPNConfig: true,
				name:               "ALPNServer-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					NextProtos: []string{"foo", "bar", "baz"},
				},
				flags: []string{
					"-expect-advertised-alpn", "\x03foo\x03bar\x03baz",
					"-select-alpn", "foo",
				},
				expectations: connectionExpectations{
					nextProto:     "foo",
					nextProtoType: alpn,
				},
				resumeSession: true,
			})

			var shouldDeclineALPNFail bool
			var declineALPNError, declineALPNLocalError string
			if protocol == quic {
				// ALPN is mandatory in QUIC.
				shouldDeclineALPNFail = true
				declineALPNError = ":NO_APPLICATION_PROTOCOL:"
				declineALPNLocalError = "remote error: no application protocol"
			}
			testCases = append(testCases, testCase{
				protocol:           protocol,
				testType:           serverTest,
				skipQUICALPNConfig: true,
				name:               "ALPNServer-Decline-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					NextProtos: []string{"foo", "bar", "baz"},
				},
				flags: []string{"-decline-alpn"},
				expectations: connectionExpectations{
					noNextProto: true,
				},
				resumeSession:      true,
				shouldFail:         shouldDeclineALPNFail,
				expectedError:      declineALPNError,
				expectedLocalError: declineALPNLocalError,
			})

			testCases = append(testCases, testCase{
				protocol:           protocol,
				testType:           serverTest,
				skipQUICALPNConfig: true,
				name:               "ALPNServer-Reject-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					NextProtos: []string{"foo", "bar", "baz"},
				},
				flags:              []string{"-reject-alpn"},
				shouldFail:         true,
				expectedError:      ":NO_APPLICATION_PROTOCOL:",
				expectedLocalError: "remote error: no application protocol",
			})

			// Test that the server implementation catches itself if the
			// callback tries to return an invalid empty ALPN protocol.
			testCases = append(testCases, testCase{
				protocol:           protocol,
				testType:           serverTest,
				skipQUICALPNConfig: true,
				name:               "ALPNServer-SelectEmpty-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					NextProtos: []string{"foo", "bar", "baz"},
				},
				flags: []string{
					"-expect-advertised-alpn", "\x03foo\x03bar\x03baz",
					"-select-empty-alpn",
				},
				shouldFail:         true,
				expectedLocalError: "remote error: internal error",
				expectedError:      ":INVALID_ALPN_PROTOCOL:",
			})

			// Test ALPN in async mode as well to ensure that extensions callbacks are only
			// called once.
			testCases = append(testCases, testCase{
				protocol:           protocol,
				testType:           serverTest,
				skipQUICALPNConfig: true,
				name:               "ALPNServer-Async-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					NextProtos: []string{"foo", "bar", "baz"},
					// Prior to TLS 1.3, exercise the asynchronous session callback.
					SessionTicketsDisabled: ver.version < VersionTLS13,
				},
				flags: []string{
					"-expect-advertised-alpn", "\x03foo\x03bar\x03baz",
					"-select-alpn", "foo",
					"-async",
				},
				expectations: connectionExpectations{
					nextProto:     "foo",
					nextProtoType: alpn,
				},
				resumeSession: true,
			})

			var emptyString string
			testCases = append(testCases, testCase{
				protocol:           protocol,
				testType:           clientTest,
				skipQUICALPNConfig: true,
				name:               "ALPNClient-EmptyProtocolName-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					NextProtos: []string{""},
					Bugs: ProtocolBugs{
						// A server returning an empty ALPN protocol
						// should be rejected.
						ALPNProtocol: &emptyString,
					},
				},
				flags: []string{
					"-advertise-alpn", "\x03foo",
				},
				shouldFail:    true,
				expectedError: ":PARSE_TLSEXT:",
			})
			testCases = append(testCases, testCase{
				protocol:           protocol,
				testType:           serverTest,
				skipQUICALPNConfig: true,
				name:               "ALPNServer-EmptyProtocolName-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					// A ClientHello containing an empty ALPN protocol
					// should be rejected.
					NextProtos: []string{"foo", "", "baz"},
				},
				flags: []string{
					"-select-alpn", "foo",
				},
				shouldFail:    true,
				expectedError: ":PARSE_TLSEXT:",
			})

			// Test NPN and the interaction with ALPN.
			if ver.version < VersionTLS13 && protocol == tls {
				// Test that the server prefers ALPN over NPN.
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "ALPNServer-Preferred-" + suffix,
					config: Config{
						MaxVersion: ver.version,
						NextProtos: []string{"foo", "bar", "baz"},
					},
					flags: []string{
						"-expect-advertised-alpn", "\x03foo\x03bar\x03baz",
						"-select-alpn", "foo",
						"-advertise-npn", "\x03foo\x03bar\x03baz",
					},
					expectations: connectionExpectations{
						nextProto:     "foo",
						nextProtoType: alpn,
					},
					resumeSession: true,
				})
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "ALPNServer-Preferred-Swapped-" + suffix,
					config: Config{
						MaxVersion: ver.version,
						NextProtos: []string{"foo", "bar", "baz"},
						Bugs: ProtocolBugs{
							SwapNPNAndALPN: true,
						},
					},
					flags: []string{
						"-expect-advertised-alpn", "\x03foo\x03bar\x03baz",
						"-select-alpn", "foo",
						"-advertise-npn", "\x03foo\x03bar\x03baz",
					},
					expectations: connectionExpectations{
						nextProto:     "foo",
						nextProtoType: alpn,
					},
					resumeSession: true,
				})

				// Test that negotiating both NPN and ALPN is forbidden.
				testCases = append(testCases, testCase{
					protocol: protocol,
					name:     "NegotiateALPNAndNPN-" + suffix,
					config: Config{
						MaxVersion: ver.version,
						NextProtos: []string{"foo", "bar", "baz"},
						Bugs: ProtocolBugs{
							NegotiateALPNAndNPN: true,
						},
					},
					flags: []string{
						"-advertise-alpn", "\x03foo",
						"-select-next-proto", "foo",
					},
					shouldFail:    true,
					expectedError: ":NEGOTIATED_BOTH_NPN_AND_ALPN:",
				})
				testCases = append(testCases, testCase{
					protocol: protocol,
					name:     "NegotiateALPNAndNPN-Swapped-" + suffix,
					config: Config{
						MaxVersion: ver.version,
						NextProtos: []string{"foo", "bar", "baz"},
						Bugs: ProtocolBugs{
							NegotiateALPNAndNPN: true,
							SwapNPNAndALPN:      true,
						},
					},
					flags: []string{
						"-advertise-alpn", "\x03foo",
						"-select-next-proto", "foo",
					},
					shouldFail:    true,
					expectedError: ":NEGOTIATED_BOTH_NPN_AND_ALPN:",
				})
			}

			// Test missing ALPN in QUIC
			if protocol == quic {
				testCases = append(testCases, testCase{
					testType: clientTest,
					protocol: protocol,
					name:     "Client-ALPNMissingFromConfig-" + suffix,
					config: Config{
						MinVersion: ver.version,
						MaxVersion: ver.version,
					},
					skipQUICALPNConfig: true,
					shouldFail:         true,
					expectedError:      ":NO_APPLICATION_PROTOCOL:",
				})
				testCases = append(testCases, testCase{
					testType: clientTest,
					protocol: protocol,
					name:     "Client-ALPNMissing-" + suffix,
					config: Config{
						MinVersion: ver.version,
						MaxVersion: ver.version,
					},
					flags: []string{
						"-advertise-alpn", "\x03foo",
					},
					skipQUICALPNConfig: true,
					shouldFail:         true,
					expectedError:      ":NO_APPLICATION_PROTOCOL:",
					expectedLocalError: "remote error: no application protocol",
				})
				testCases = append(testCases, testCase{
					testType: serverTest,
					protocol: protocol,
					name:     "Server-ALPNMissing-" + suffix,
					config: Config{
						MinVersion: ver.version,
						MaxVersion: ver.version,
					},
					skipQUICALPNConfig: true,
					shouldFail:         true,
					expectedError:      ":NO_APPLICATION_PROTOCOL:",
					expectedLocalError: "remote error: no application protocol",
				})
				testCases = append(testCases, testCase{
					testType: serverTest,
					protocol: protocol,
					name:     "Server-ALPNMismatch-" + suffix,
					config: Config{
						MinVersion: ver.version,
						MaxVersion: ver.version,
						NextProtos: []string{"foo"},
					},
					flags: []string{
						"-decline-alpn",
					},
					skipQUICALPNConfig: true,
					shouldFail:         true,
					expectedError:      ":NO_APPLICATION_PROTOCOL:",
					expectedLocalError: "remote error: no application protocol",
				})
			}

			// Test ALPS.
			if ver.version >= VersionTLS13 {
				// Test basic client with different ALPS codepoint.
				for _, alpsCodePoint := range []ALPSUseCodepoint{ALPSUseCodepointNew, ALPSUseCodepointOld} {
					flags := []string{}
					expectations := connectionExpectations{
						peerApplicationSettingsOld: []byte("shim1"),
					}
					resumeExpectations := &connectionExpectations{
						peerApplicationSettingsOld: []byte("shim2"),
					}

					if alpsCodePoint == ALPSUseCodepointNew {
						flags = append(flags, "-alps-use-new-codepoint")
						expectations = connectionExpectations{
							peerApplicationSettings: []byte("shim1"),
						}
						resumeExpectations = &connectionExpectations{
							peerApplicationSettings: []byte("shim2"),
						}
					}

					flags = append(flags,
						"-advertise-alpn", "\x05proto",
						"-expect-alpn", "proto",
						"-on-initial-application-settings", "proto,shim1",
						"-on-initial-expect-peer-application-settings", "runner1",
						"-on-resume-application-settings", "proto,shim2",
						"-on-resume-expect-peer-application-settings", "runner2")

					// Test that server can negotiate ALPS, including different values
					// on resumption.
					testCases = append(testCases, testCase{
						protocol:           protocol,
						testType:           clientTest,
						name:               fmt.Sprintf("ALPS-Basic-Client-%s-%s", alpsCodePoint, suffix),
						skipQUICALPNConfig: true,
						config: Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto"},
							ApplicationSettings: map[string][]byte{"proto": []byte("runner1")},
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						resumeConfig: &Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto"},
							ApplicationSettings: map[string][]byte{"proto": []byte("runner2")},
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						resumeSession:      true,
						expectations:       expectations,
						resumeExpectations: resumeExpectations,
						flags:              flags,
					})

					// Test basic server with different ALPS codepoint.
					flags = []string{}
					expectations = connectionExpectations{
						peerApplicationSettingsOld: []byte("shim1"),
					}
					resumeExpectations = &connectionExpectations{
						peerApplicationSettingsOld: []byte("shim2"),
					}

					if alpsCodePoint == ALPSUseCodepointNew {
						flags = append(flags, "-alps-use-new-codepoint")
						expectations = connectionExpectations{
							peerApplicationSettings: []byte("shim1"),
						}
						resumeExpectations = &connectionExpectations{
							peerApplicationSettings: []byte("shim2"),
						}
					}

					flags = append(flags,
						"-select-alpn", "proto",
						"-on-initial-application-settings", "proto,shim1",
						"-on-initial-expect-peer-application-settings", "runner1",
						"-on-resume-application-settings", "proto,shim2",
						"-on-resume-expect-peer-application-settings", "runner2")

					// Test that server can negotiate ALPS, including different values
					// on resumption.
					testCases = append(testCases, testCase{
						protocol:           protocol,
						testType:           serverTest,
						name:               fmt.Sprintf("ALPS-Basic-Server-%s-%s", alpsCodePoint, suffix),
						skipQUICALPNConfig: true,
						config: Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto"},
							ApplicationSettings: map[string][]byte{"proto": []byte("runner1")},
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						resumeConfig: &Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto"},
							ApplicationSettings: map[string][]byte{"proto": []byte("runner2")},
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						resumeSession:      true,
						expectations:       expectations,
						resumeExpectations: resumeExpectations,
						flags:              flags,
					})

					// Try different ALPS codepoint for all the existing tests.
					alpsFlags := []string{}
					expectations = connectionExpectations{
						peerApplicationSettingsOld: []byte("shim1"),
					}
					resumeExpectations = &connectionExpectations{
						peerApplicationSettingsOld: []byte("shim2"),
					}
					if alpsCodePoint == ALPSUseCodepointNew {
						alpsFlags = append(alpsFlags, "-alps-use-new-codepoint")
						expectations = connectionExpectations{
							peerApplicationSettings: []byte("shim1"),
						}
						resumeExpectations = &connectionExpectations{
							peerApplicationSettings: []byte("shim2"),
						}
					}

					// Test that the server can defer its ALPS configuration to the ALPN
					// selection callback.
					testCases = append(testCases, testCase{
						protocol:           protocol,
						testType:           serverTest,
						name:               fmt.Sprintf("ALPS-Basic-Server-Defer-%s-%s", alpsCodePoint, suffix),
						skipQUICALPNConfig: true,
						config: Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto"},
							ApplicationSettings: map[string][]byte{"proto": []byte("runner1")},
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						resumeConfig: &Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto"},
							ApplicationSettings: map[string][]byte{"proto": []byte("runner2")},
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						resumeSession:      true,
						expectations:       expectations,
						resumeExpectations: resumeExpectations,
						flags: append([]string{
							"-select-alpn", "proto",
							"-defer-alps",
							"-on-initial-application-settings", "proto,shim1",
							"-on-initial-expect-peer-application-settings", "runner1",
							"-on-resume-application-settings", "proto,shim2",
							"-on-resume-expect-peer-application-settings", "runner2",
						}, alpsFlags...),
					})

					expectations = connectionExpectations{
						peerApplicationSettingsOld: []byte{},
					}
					if alpsCodePoint == ALPSUseCodepointNew {
						expectations = connectionExpectations{
							peerApplicationSettings: []byte{},
						}
					}
					// Test the client and server correctly handle empty settings.
					testCases = append(testCases, testCase{
						protocol:           protocol,
						testType:           clientTest,
						name:               fmt.Sprintf("ALPS-Empty-Client-%s-%s", alpsCodePoint, suffix),
						skipQUICALPNConfig: true,
						config: Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto"},
							ApplicationSettings: map[string][]byte{"proto": {}},
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						resumeSession: true,
						expectations:  expectations,
						flags: append([]string{
							"-advertise-alpn", "\x05proto",
							"-expect-alpn", "proto",
							"-application-settings", "proto,",
							"-expect-peer-application-settings", "",
						}, alpsFlags...),
					})
					testCases = append(testCases, testCase{
						protocol:           protocol,
						testType:           serverTest,
						name:               fmt.Sprintf("ALPS-Empty-Server-%s-%s", alpsCodePoint, suffix),
						skipQUICALPNConfig: true,
						config: Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto"},
							ApplicationSettings: map[string][]byte{"proto": {}},
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						resumeSession: true,
						expectations:  expectations,
						flags: append([]string{
							"-select-alpn", "proto",
							"-application-settings", "proto,",
							"-expect-peer-application-settings", "",
						}, alpsFlags...),
					})

					bugs := ProtocolBugs{
						AlwaysNegotiateApplicationSettingsOld: true,
					}
					if alpsCodePoint == ALPSUseCodepointNew {
						bugs = ProtocolBugs{
							AlwaysNegotiateApplicationSettingsNew: true,
						}
					}
					// Test the client rejects application settings from the server on
					// protocols it doesn't have them.
					testCases = append(testCases, testCase{
						protocol:           protocol,
						testType:           clientTest,
						name:               fmt.Sprintf("ALPS-UnsupportedProtocol-Client-%s-%s", alpsCodePoint, suffix),
						skipQUICALPNConfig: true,
						config: Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto1"},
							ApplicationSettings: map[string][]byte{"proto1": []byte("runner")},
							Bugs:                bugs,
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						// The client supports ALPS with "proto2", but not "proto1".
						flags: append([]string{
							"-advertise-alpn", "\x06proto1\x06proto2",
							"-application-settings", "proto2,shim",
							"-expect-alpn", "proto1",
						}, alpsFlags...),
						// The server sends ALPS with "proto1", which is invalid.
						shouldFail:         true,
						expectedError:      ":INVALID_ALPN_PROTOCOL:",
						expectedLocalError: "remote error: illegal parameter",
					})

					// Test client rejects application settings from the server when
					// server sends the wrong ALPS codepoint.
					bugs = ProtocolBugs{
						AlwaysNegotiateApplicationSettingsOld: true,
					}
					if alpsCodePoint == ALPSUseCodepointOld {
						bugs = ProtocolBugs{
							AlwaysNegotiateApplicationSettingsNew: true,
						}
					}

					testCases = append(testCases, testCase{
						protocol:           protocol,
						testType:           clientTest,
						name:               fmt.Sprintf("ALPS-WrongServerCodepoint-Client-%s-%s", alpsCodePoint, suffix),
						skipQUICALPNConfig: true,
						config: Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto"},
							ApplicationSettings: map[string][]byte{"proto": {}},
							Bugs:                bugs,
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						flags: append([]string{
							"-advertise-alpn", "\x05proto",
							"-expect-alpn", "proto",
							"-application-settings", "proto,",
							"-expect-peer-application-settings", "",
						}, alpsFlags...),
						shouldFail:         true,
						expectedError:      ":UNEXPECTED_EXTENSION:",
						expectedLocalError: "remote error: unsupported extension",
					})

					// Test server ignore wrong codepoint from client.
					clientSends := ALPSUseCodepointNew
					if alpsCodePoint == ALPSUseCodepointNew {
						clientSends = ALPSUseCodepointOld
					}

					testCases = append(testCases, testCase{
						protocol:           protocol,
						testType:           serverTest,
						name:               fmt.Sprintf("ALPS-IgnoreClientWrongCodepoint-Server-%s-%s", alpsCodePoint, suffix),
						skipQUICALPNConfig: true,
						config: Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto"},
							ApplicationSettings: map[string][]byte{"proto": []byte("runner1")},
							ALPSUseNewCodepoint: clientSends,
						},
						resumeConfig: &Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto"},
							ApplicationSettings: map[string][]byte{"proto": []byte("runner2")},
							ALPSUseNewCodepoint: clientSends,
						},
						resumeSession: true,
						flags: append([]string{
							"-select-alpn", "proto",
							"-on-initial-application-settings", "proto,shim1",
							"-on-resume-application-settings", "proto,shim2",
						}, alpsFlags...),
					})

					// Test the server declines ALPS if it doesn't support it for the
					// specified protocol.
					testCases = append(testCases, testCase{
						protocol:           protocol,
						testType:           serverTest,
						name:               fmt.Sprintf("ALPS-UnsupportedProtocol-Server-%s-%s", alpsCodePoint, suffix),
						skipQUICALPNConfig: true,
						config: Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto1"},
							ApplicationSettings: map[string][]byte{"proto1": []byte("runner")},
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						// The server supports ALPS with "proto2", but not "proto1".
						flags: append([]string{
							"-select-alpn", "proto1",
							"-application-settings", "proto2,shim",
						}, alpsFlags...),
					})

					// Test the client rejects application settings from the server when
					// it always negotiate both codepoint.
					testCases = append(testCases, testCase{
						protocol:           protocol,
						testType:           clientTest,
						name:               fmt.Sprintf("ALPS-UnsupportedProtocol-Client-ServerBoth-%s-%s", alpsCodePoint, suffix),
						skipQUICALPNConfig: true,
						config: Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto1"},
							ApplicationSettings: map[string][]byte{"proto1": []byte("runner")},
							Bugs: ProtocolBugs{
								AlwaysNegotiateApplicationSettingsBoth: true,
							},
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						flags: append([]string{
							"-advertise-alpn", "\x06proto1\x06proto2",
							"-application-settings", "proto1,shim",
							"-expect-alpn", "proto1",
						}, alpsFlags...),
						// The server sends ALPS with both application settings, which is invalid.
						shouldFail:         true,
						expectedError:      ":UNEXPECTED_EXTENSION:",
						expectedLocalError: "remote error: unsupported extension",
					})

					expectations = connectionExpectations{
						peerApplicationSettingsOld: []byte("shim"),
					}
					if alpsCodePoint == ALPSUseCodepointNew {
						expectations = connectionExpectations{
							peerApplicationSettings: []byte("shim"),
						}
					}

					// Test that the server rejects a missing application_settings extension.
					testCases = append(testCases, testCase{
						protocol:           protocol,
						testType:           serverTest,
						name:               fmt.Sprintf("ALPS-OmitClientApplicationSettings-%s-%s", alpsCodePoint, suffix),
						skipQUICALPNConfig: true,
						config: Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto"},
							ApplicationSettings: map[string][]byte{"proto": []byte("runner")},
							Bugs: ProtocolBugs{
								OmitClientApplicationSettings: true,
							},
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						flags: append([]string{
							"-select-alpn", "proto",
							"-application-settings", "proto,shim",
						}, alpsFlags...),
						// The runner is a client, so it only processes the shim's alert
						// after checking connection state.
						expectations:       expectations,
						shouldFail:         true,
						expectedError:      ":MISSING_EXTENSION:",
						expectedLocalError: "remote error: missing extension",
					})

					// Test that the server rejects a missing EncryptedExtensions message.
					testCases = append(testCases, testCase{
						protocol:           protocol,
						testType:           serverTest,
						name:               fmt.Sprintf("ALPS-OmitClientEncryptedExtensions-%s-%s", alpsCodePoint, suffix),
						skipQUICALPNConfig: true,
						config: Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto"},
							ApplicationSettings: map[string][]byte{"proto": []byte("runner")},
							Bugs: ProtocolBugs{
								OmitClientEncryptedExtensions: true,
							},
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						flags: append([]string{
							"-select-alpn", "proto",
							"-application-settings", "proto,shim",
						}, alpsFlags...),
						// The runner is a client, so it only processes the shim's alert
						// after checking connection state.
						expectations:       expectations,
						shouldFail:         true,
						expectedError:      ":UNEXPECTED_MESSAGE:",
						expectedLocalError: "remote error: unexpected message",
					})

					// Test that the server rejects an unexpected EncryptedExtensions message.
					testCases = append(testCases, testCase{
						protocol: protocol,
						testType: serverTest,
						name:     fmt.Sprintf("UnexpectedClientEncryptedExtensions-%s-%s", alpsCodePoint, suffix),
						config: Config{
							MaxVersion: ver.version,
							Bugs: ProtocolBugs{
								AlwaysSendClientEncryptedExtensions: true,
							},
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						shouldFail:         true,
						expectedError:      ":UNEXPECTED_MESSAGE:",
						expectedLocalError: "remote error: unexpected message",
					})

					// Test that the server rejects an unexpected extension in an
					// expected EncryptedExtensions message.
					testCases = append(testCases, testCase{
						protocol:           protocol,
						testType:           serverTest,
						name:               fmt.Sprintf("ExtraClientEncryptedExtension-%s-%s", alpsCodePoint, suffix),
						skipQUICALPNConfig: true,
						config: Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"proto"},
							ApplicationSettings: map[string][]byte{"proto": []byte("runner")},
							Bugs: ProtocolBugs{
								SendExtraClientEncryptedExtension: true,
							},
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						flags: append([]string{
							"-select-alpn", "proto",
							"-application-settings", "proto,shim",
						}, alpsFlags...),
						// The runner is a client, so it only processes the shim's alert
						// after checking connection state.
						expectations:       expectations,
						shouldFail:         true,
						expectedError:      ":UNEXPECTED_EXTENSION:",
						expectedLocalError: "remote error: unsupported extension",
					})

					// Test that ALPS is carried over on 0-RTT.
					// TODO(crbug.com/381113363): Support 0-RTT in DTLS 1.3.
					if protocol != dtls {
						for _, empty := range []bool{false, true} {
							maybeEmpty := ""
							runnerSettings := "runner"
							shimSettings := "shim"
							if empty {
								maybeEmpty = "Empty-"
								runnerSettings = ""
								shimSettings = ""
							}

							expectations = connectionExpectations{
								peerApplicationSettingsOld: []byte(shimSettings),
							}
							if alpsCodePoint == ALPSUseCodepointNew {
								expectations = connectionExpectations{
									peerApplicationSettings: []byte(shimSettings),
								}
							}
							testCases = append(testCases, testCase{
								protocol:           protocol,
								testType:           clientTest,
								name:               fmt.Sprintf("ALPS-EarlyData-Client-%s-%s-%s", alpsCodePoint, maybeEmpty, suffix),
								skipQUICALPNConfig: true,
								config: Config{
									MaxVersion:          ver.version,
									NextProtos:          []string{"proto"},
									ApplicationSettings: map[string][]byte{"proto": []byte(runnerSettings)},
									ALPSUseNewCodepoint: alpsCodePoint,
								},
								resumeSession: true,
								earlyData:     true,
								flags: append([]string{
									"-advertise-alpn", "\x05proto",
									"-expect-alpn", "proto",
									"-application-settings", "proto," + shimSettings,
									"-expect-peer-application-settings", runnerSettings,
								}, alpsFlags...),
								expectations: expectations,
							})
							testCases = append(testCases, testCase{
								protocol:           protocol,
								testType:           serverTest,
								name:               fmt.Sprintf("ALPS-EarlyData-Server-%s-%s-%s", alpsCodePoint, maybeEmpty, suffix),
								skipQUICALPNConfig: true,
								config: Config{
									MaxVersion:          ver.version,
									NextProtos:          []string{"proto"},
									ApplicationSettings: map[string][]byte{"proto": []byte(runnerSettings)},
									ALPSUseNewCodepoint: alpsCodePoint,
								},
								resumeSession: true,
								earlyData:     true,
								flags: append([]string{
									"-select-alpn", "proto",
									"-application-settings", "proto," + shimSettings,
									"-expect-peer-application-settings", runnerSettings,
								}, alpsFlags...),
								expectations: expectations,
							})

							// Sending application settings in 0-RTT handshakes is forbidden.
							testCases = append(testCases, testCase{
								protocol:           protocol,
								testType:           clientTest,
								name:               fmt.Sprintf("ALPS-EarlyData-SendApplicationSettingsWithEarlyData-Client-%s-%s-%s", alpsCodePoint, maybeEmpty, suffix),
								skipQUICALPNConfig: true,
								config: Config{
									MaxVersion:          ver.version,
									NextProtos:          []string{"proto"},
									ApplicationSettings: map[string][]byte{"proto": []byte(runnerSettings)},
									Bugs: ProtocolBugs{
										SendApplicationSettingsWithEarlyData: true,
									},
									ALPSUseNewCodepoint: alpsCodePoint,
								},
								resumeSession: true,
								earlyData:     true,
								flags: append([]string{
									"-advertise-alpn", "\x05proto",
									"-expect-alpn", "proto",
									"-application-settings", "proto," + shimSettings,
									"-expect-peer-application-settings", runnerSettings,
								}, alpsFlags...),
								expectations:       expectations,
								shouldFail:         true,
								expectedError:      ":UNEXPECTED_EXTENSION_ON_EARLY_DATA:",
								expectedLocalError: "remote error: illegal parameter",
							})
							testCases = append(testCases, testCase{
								protocol:           protocol,
								testType:           serverTest,
								name:               fmt.Sprintf("ALPS-EarlyData-SendApplicationSettingsWithEarlyData-Server-%s-%s-%s", alpsCodePoint, maybeEmpty, suffix),
								skipQUICALPNConfig: true,
								config: Config{
									MaxVersion:          ver.version,
									NextProtos:          []string{"proto"},
									ApplicationSettings: map[string][]byte{"proto": []byte(runnerSettings)},
									Bugs: ProtocolBugs{
										SendApplicationSettingsWithEarlyData: true,
									},
									ALPSUseNewCodepoint: alpsCodePoint,
								},
								resumeSession: true,
								earlyData:     true,
								flags: append([]string{
									"-select-alpn", "proto",
									"-application-settings", "proto," + shimSettings,
									"-expect-peer-application-settings", runnerSettings,
								}, alpsFlags...),
								expectations:       expectations,
								shouldFail:         true,
								expectedError:      ":UNEXPECTED_MESSAGE:",
								expectedLocalError: "remote error: unexpected message",
							})
						}

						// Test that the client and server each decline early data if local
						// ALPS preferences has changed for the current connection.
						alpsMismatchTests := []struct {
							name                            string
							initialSettings, resumeSettings []byte
						}{
							{"DifferentValues", []byte("settings1"), []byte("settings2")},
							{"OnOff", []byte("settings"), nil},
							{"OffOn", nil, []byte("settings")},
							// The empty settings value should not be mistaken for ALPS not
							// being negotiated.
							{"OnEmpty", []byte("settings"), []byte{}},
							{"EmptyOn", []byte{}, []byte("settings")},
							{"EmptyOff", []byte{}, nil},
							{"OffEmpty", nil, []byte{}},
						}
						for _, test := range alpsMismatchTests {
							flags := []string{"-on-resume-expect-early-data-reason", "alps_mismatch"}
							flags = append(flags, alpsFlags...)
							if test.initialSettings != nil {
								flags = append(flags, "-on-initial-application-settings", "proto,"+string(test.initialSettings))
								flags = append(flags, "-on-initial-expect-peer-application-settings", "runner")
							}
							if test.resumeSettings != nil {
								flags = append(flags, "-on-resume-application-settings", "proto,"+string(test.resumeSettings))
								flags = append(flags, "-on-resume-expect-peer-application-settings", "runner")
							}

							expectations = connectionExpectations{
								peerApplicationSettingsOld: test.initialSettings,
							}
							resumeExpectations = &connectionExpectations{
								peerApplicationSettingsOld: test.resumeSettings,
							}
							if alpsCodePoint == ALPSUseCodepointNew {
								expectations = connectionExpectations{
									peerApplicationSettings: test.initialSettings,
								}
								resumeExpectations = &connectionExpectations{
									peerApplicationSettings: test.resumeSettings,
								}
							}
							// The client should not offer early data if the session is
							// inconsistent with the new configuration. Note that if
							// the session did not negotiate ALPS (test.initialSettings
							// is nil), the client always offers early data.
							if test.initialSettings != nil {
								testCases = append(testCases, testCase{
									protocol:           protocol,
									testType:           clientTest,
									name:               fmt.Sprintf("ALPS-EarlyData-Mismatch-%s-Client-%s-%s", test.name, alpsCodePoint, suffix),
									skipQUICALPNConfig: true,
									config: Config{
										MaxVersion:          ver.version,
										MaxEarlyDataSize:    16384,
										NextProtos:          []string{"proto"},
										ApplicationSettings: map[string][]byte{"proto": []byte("runner")},
										ALPSUseNewCodepoint: alpsCodePoint,
									},
									resumeSession: true,
									flags: append([]string{
										"-enable-early-data",
										"-expect-ticket-supports-early-data",
										"-expect-no-offer-early-data",
										"-advertise-alpn", "\x05proto",
										"-expect-alpn", "proto",
									}, flags...),
									expectations:       expectations,
									resumeExpectations: resumeExpectations,
								})
							}

							// The server should reject early data if the session is
							// inconsistent with the new selection.
							testCases = append(testCases, testCase{
								protocol:           protocol,
								testType:           serverTest,
								name:               fmt.Sprintf("ALPS-EarlyData-Mismatch-%s-Server-%s-%s", test.name, alpsCodePoint, suffix),
								skipQUICALPNConfig: true,
								config: Config{
									MaxVersion:          ver.version,
									NextProtos:          []string{"proto"},
									ApplicationSettings: map[string][]byte{"proto": []byte("runner")},
									ALPSUseNewCodepoint: alpsCodePoint,
								},
								resumeSession:           true,
								earlyData:               true,
								expectEarlyDataRejected: true,
								flags: append([]string{
									"-select-alpn", "proto",
								}, flags...),
								expectations:       expectations,
								resumeExpectations: resumeExpectations,
							})
						}

						// Test that 0-RTT continues working when the shim configures
						// ALPS but the peer does not.
						testCases = append(testCases, testCase{
							protocol:           protocol,
							testType:           clientTest,
							name:               fmt.Sprintf("ALPS-EarlyData-Client-ServerDecline-%s-%s", alpsCodePoint, suffix),
							skipQUICALPNConfig: true,
							config: Config{
								MaxVersion:          ver.version,
								NextProtos:          []string{"proto"},
								ALPSUseNewCodepoint: alpsCodePoint,
							},
							resumeSession: true,
							earlyData:     true,
							flags: append([]string{
								"-advertise-alpn", "\x05proto",
								"-expect-alpn", "proto",
								"-application-settings", "proto,shim",
							}, alpsFlags...),
						})
						testCases = append(testCases, testCase{
							protocol:           protocol,
							testType:           serverTest,
							name:               fmt.Sprintf("ALPS-EarlyData-Server-ClientNoOffe-%s-%s", alpsCodePoint, suffix),
							skipQUICALPNConfig: true,
							config: Config{
								MaxVersion:          ver.version,
								NextProtos:          []string{"proto"},
								ALPSUseNewCodepoint: alpsCodePoint,
							},
							resumeSession: true,
							earlyData:     true,
							flags: append([]string{
								"-select-alpn", "proto",
								"-application-settings", "proto,shim",
							}, alpsFlags...),
						})
					}
				}
			} else {
				// Test the client rejects the ALPS extension if the server
				// negotiated TLS 1.2 or below.
				for _, alpsCodePoint := range []ALPSUseCodepoint{ALPSUseCodepointNew, ALPSUseCodepointOld} {
					flags := []string{
						"-advertise-alpn", "\x03foo",
						"-expect-alpn", "foo",
						"-application-settings", "foo,shim",
					}
					bugs := ProtocolBugs{
						AlwaysNegotiateApplicationSettingsOld: true,
					}
					if alpsCodePoint == ALPSUseCodepointNew {
						flags = append(flags, "-alps-use-new-codepoint")
						bugs = ProtocolBugs{
							AlwaysNegotiateApplicationSettingsNew: true,
						}
					}
					testCases = append(testCases, testCase{
						protocol: protocol,
						testType: clientTest,
						name:     fmt.Sprintf("ALPS-Reject-Client-%s-%s", alpsCodePoint, suffix),
						config: Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"foo"},
							ApplicationSettings: map[string][]byte{"foo": []byte("runner")},
							Bugs:                bugs,
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						flags:              flags,
						shouldFail:         true,
						expectedError:      ":UNEXPECTED_EXTENSION:",
						expectedLocalError: "remote error: unsupported extension",
					})

					flags = []string{
						"-on-resume-advertise-alpn", "\x03foo",
						"-on-resume-expect-alpn", "foo",
						"-on-resume-application-settings", "foo,shim",
					}
					bugs = ProtocolBugs{
						AlwaysNegotiateApplicationSettingsOld: true,
					}
					if alpsCodePoint == ALPSUseCodepointNew {
						flags = append(flags, "-alps-use-new-codepoint")
						bugs = ProtocolBugs{
							AlwaysNegotiateApplicationSettingsNew: true,
						}
					}
					testCases = append(testCases, testCase{
						protocol: protocol,
						testType: clientTest,
						name:     fmt.Sprintf("ALPS-Reject-Client-Resume-%s-%s", alpsCodePoint, suffix),
						config: Config{
							MaxVersion: ver.version,
						},
						resumeConfig: &Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"foo"},
							ApplicationSettings: map[string][]byte{"foo": []byte("runner")},
							Bugs:                bugs,
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						resumeSession:      true,
						flags:              flags,
						shouldFail:         true,
						expectedError:      ":UNEXPECTED_EXTENSION:",
						expectedLocalError: "remote error: unsupported extension",
					})

					// Test the server declines ALPS if it negotiates TLS 1.2 or below.
					flags = []string{
						"-select-alpn", "foo",
						"-application-settings", "foo,shim",
					}
					if alpsCodePoint == ALPSUseCodepointNew {
						flags = append(flags, "-alps-use-new-codepoint")
					}
					testCases = append(testCases, testCase{
						protocol: protocol,
						testType: serverTest,
						name:     fmt.Sprintf("ALPS-Decline-Server-%s-%s", alpsCodePoint, suffix),
						config: Config{
							MaxVersion:          ver.version,
							NextProtos:          []string{"foo"},
							ApplicationSettings: map[string][]byte{"foo": []byte("runner")},
							ALPSUseNewCodepoint: alpsCodePoint,
						},
						// Test both TLS 1.2 full and resumption handshakes.
						resumeSession: true,
						flags:         flags,
						// If not specified, runner and shim both implicitly expect ALPS
						// is not negotiated.
					})
				}
			}

			// Test QUIC transport params
			if protocol == quic {
				// Client sends params
				for _, clientConfig := range []QUICUseCodepoint{QUICUseCodepointStandard, QUICUseCodepointLegacy} {
					for _, serverSends := range []QUICUseCodepoint{QUICUseCodepointStandard, QUICUseCodepointLegacy, QUICUseCodepointBoth, QUICUseCodepointNeither} {
						useCodepointFlag := "0"
						if clientConfig == QUICUseCodepointLegacy {
							useCodepointFlag = "1"
						}
						flags := []string{
							"-quic-transport-params",
							base64FlagValue([]byte{1, 2}),
							"-quic-use-legacy-codepoint", useCodepointFlag,
						}
						expectations := connectionExpectations{
							quicTransportParams: []byte{1, 2},
						}
						shouldFail := false
						expectedError := ""
						expectedLocalError := ""
						if clientConfig == QUICUseCodepointLegacy {
							expectations = connectionExpectations{
								quicTransportParamsLegacy: []byte{1, 2},
							}
						}
						if serverSends != clientConfig {
							expectations = connectionExpectations{}
							shouldFail = true
							if serverSends == QUICUseCodepointNeither {
								expectedError = ":MISSING_EXTENSION:"
							} else {
								expectedLocalError = "remote error: unsupported extension"
							}
						} else {
							flags = append(flags,
								"-expect-quic-transport-params",
								base64FlagValue([]byte{3, 4}))
						}
						testCases = append(testCases, testCase{
							testType: clientTest,
							protocol: protocol,
							name:     fmt.Sprintf("QUICTransportParams-Client-Client%s-Server%s-%s", clientConfig, serverSends, suffix),
							config: Config{
								MinVersion:                            ver.version,
								MaxVersion:                            ver.version,
								QUICTransportParams:                   []byte{3, 4},
								QUICTransportParamsUseLegacyCodepoint: serverSends,
							},
							flags:                     flags,
							expectations:              expectations,
							shouldFail:                shouldFail,
							expectedError:             expectedError,
							expectedLocalError:        expectedLocalError,
							skipTransportParamsConfig: true,
						})
					}
				}
				// Server sends params
				for _, clientSends := range []QUICUseCodepoint{QUICUseCodepointStandard, QUICUseCodepointLegacy, QUICUseCodepointBoth, QUICUseCodepointNeither} {
					for _, serverConfig := range []QUICUseCodepoint{QUICUseCodepointStandard, QUICUseCodepointLegacy} {
						expectations := connectionExpectations{
							quicTransportParams: []byte{3, 4},
						}
						shouldFail := false
						expectedError := ""
						useCodepointFlag := "0"
						if serverConfig == QUICUseCodepointLegacy {
							useCodepointFlag = "1"
							expectations = connectionExpectations{
								quicTransportParamsLegacy: []byte{3, 4},
							}
						}
						flags := []string{
							"-quic-transport-params",
							base64FlagValue([]byte{3, 4}),
							"-quic-use-legacy-codepoint", useCodepointFlag,
						}
						if clientSends != QUICUseCodepointBoth && clientSends != serverConfig {
							expectations = connectionExpectations{}
							shouldFail = true
							expectedError = ":MISSING_EXTENSION:"
						} else {
							flags = append(flags,
								"-expect-quic-transport-params",
								base64FlagValue([]byte{1, 2}),
							)
						}
						testCases = append(testCases, testCase{
							testType: serverTest,
							protocol: protocol,
							name:     fmt.Sprintf("QUICTransportParams-Server-Client%s-Server%s-%s", clientSends, serverConfig, suffix),
							config: Config{
								MinVersion:                            ver.version,
								MaxVersion:                            ver.version,
								QUICTransportParams:                   []byte{1, 2},
								QUICTransportParamsUseLegacyCodepoint: clientSends,
							},
							flags:                     flags,
							expectations:              expectations,
							shouldFail:                shouldFail,
							expectedError:             expectedError,
							skipTransportParamsConfig: true,
						})
					}
				}
			} else {
				// Ensure non-QUIC client doesn't send QUIC transport parameters.
				for _, clientConfig := range []QUICUseCodepoint{QUICUseCodepointStandard, QUICUseCodepointLegacy} {
					useCodepointFlag := "0"
					if clientConfig == QUICUseCodepointLegacy {
						useCodepointFlag = "1"
					}
					testCases = append(testCases, testCase{
						protocol: protocol,
						testType: clientTest,
						name:     fmt.Sprintf("QUICTransportParams-Client-NotSentInNonQUIC-%s-%s", clientConfig, suffix),
						config: Config{
							MinVersion:                            ver.version,
							MaxVersion:                            ver.version,
							QUICTransportParamsUseLegacyCodepoint: clientConfig,
						},
						flags: []string{
							"-max-version",
							ver.shimFlag(protocol),
							"-quic-transport-params",
							base64FlagValue([]byte{3, 4}),
							"-quic-use-legacy-codepoint", useCodepointFlag,
						},
						shouldFail:                true,
						expectedError:             ":QUIC_TRANSPORT_PARAMETERS_MISCONFIGURED:",
						skipTransportParamsConfig: true,
					})
				}
				// Ensure non-QUIC server rejects codepoint 57 but ignores legacy 0xffa5.
				for _, clientSends := range []QUICUseCodepoint{QUICUseCodepointStandard, QUICUseCodepointLegacy, QUICUseCodepointBoth, QUICUseCodepointNeither} {
					for _, serverConfig := range []QUICUseCodepoint{QUICUseCodepointStandard, QUICUseCodepointLegacy} {
						shouldFail := false
						expectedLocalError := ""
						useCodepointFlag := "0"
						if serverConfig == QUICUseCodepointLegacy {
							useCodepointFlag = "1"
						}
						if clientSends == QUICUseCodepointStandard || clientSends == QUICUseCodepointBoth {
							shouldFail = true
							expectedLocalError = "remote error: unsupported extension"
						}
						testCases = append(testCases, testCase{
							protocol: protocol,
							testType: serverTest,
							name:     fmt.Sprintf("QUICTransportParams-NonQUICServer-Client%s-Server%s-%s", clientSends, serverConfig, suffix),
							config: Config{
								MinVersion:                            ver.version,
								MaxVersion:                            ver.version,
								QUICTransportParams:                   []byte{1, 2},
								QUICTransportParamsUseLegacyCodepoint: clientSends,
							},
							flags: []string{
								"-quic-use-legacy-codepoint", useCodepointFlag,
							},
							shouldFail:                shouldFail,
							expectedLocalError:        expectedLocalError,
							skipTransportParamsConfig: true,
						})
					}
				}

			}

			// Test ticket behavior.

			// Resume with a corrupt ticket.
			testCases = append(testCases, testCase{
				protocol: protocol,
				testType: serverTest,
				name:     "CorruptTicket-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					Bugs: ProtocolBugs{
						FilterTicket: func(in []byte) ([]byte, error) {
							in[len(in)-1] ^= 1
							return in, nil
						},
					},
				},
				resumeSession:        true,
				expectResumeRejected: true,
			})
			// Test the ticket callbacks.
			for _, aeadCallback := range []bool{false, true} {
				flag := "-use-ticket-callback"
				callbackSuffix := suffix
				if aeadCallback {
					flag = "-use-ticket-aead-callback"
					callbackSuffix += "-AEAD"
				}
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "TicketCallback-" + callbackSuffix,
					config: Config{
						MaxVersion: ver.version,
					},
					resumeSession: true,
					flags:         []string{flag},
				})
				// Only the old callback supports renewal.
				if !aeadCallback {
					testCases = append(testCases, testCase{
						protocol: protocol,
						testType: serverTest,
						name:     "TicketCallback-Renew-" + callbackSuffix,
						config: Config{
							MaxVersion: ver.version,
							Bugs: ProtocolBugs{
								ExpectNewTicket: true,
							},
						},
						flags:         []string{flag, "-renew-ticket"},
						resumeSession: true,
					})
				}
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "TicketCallback-Skip-" + callbackSuffix,
					config: Config{
						MaxVersion: ver.version,
						Bugs: ProtocolBugs{
							ExpectNoNonEmptyNewSessionTicket: true,
						},
					},
					flags: []string{flag, "-skip-ticket"},
				})

				// Test that the ticket callback is only called once when everything before
				// it in the ClientHello is asynchronous. This corrupts the ticket so
				// certificate selection callbacks run.
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "TicketCallback-SingleCall-" + callbackSuffix,
					config: Config{
						MaxVersion: ver.version,
						Bugs: ProtocolBugs{
							FilterTicket: func(in []byte) ([]byte, error) {
								in[len(in)-1] ^= 1
								return in, nil
							},
						},
					},
					resumeSession:        true,
					expectResumeRejected: true,
					flags: []string{
						flag,
						"-async",
					},
				})
			}

			// Resume with various lengths of ticket session id.
			if ver.version < VersionTLS13 {
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "TicketSessionIDLength-0-" + suffix,
					config: Config{
						MaxVersion: ver.version,
						Bugs: ProtocolBugs{
							EmptyTicketSessionID: true,
						},
					},
					resumeSession: true,
				})
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "TicketSessionIDLength-16-" + suffix,
					config: Config{
						MaxVersion: ver.version,
						Bugs: ProtocolBugs{
							TicketSessionIDLength: 16,
						},
					},
					resumeSession: true,
				})
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "TicketSessionIDLength-32-" + suffix,
					config: Config{
						MaxVersion: ver.version,
						Bugs: ProtocolBugs{
							TicketSessionIDLength: 32,
						},
					},
					resumeSession: true,
				})
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "TicketSessionIDLength-33-" + suffix,
					config: Config{
						MaxVersion: ver.version,
						Bugs: ProtocolBugs{
							TicketSessionIDLength: 33,
						},
					},
					resumeSession: true,
					shouldFail:    true,
					// The maximum session ID length is 32.
					expectedError: ":CLIENTHELLO_PARSE_FAILED:",
				})
			}

			// Basic DTLS-SRTP tests. Include fake profiles to ensure they
			// are ignored.
			if protocol == dtls {
				testCases = append(testCases, testCase{
					protocol: protocol,
					name:     "SRTP-Client-" + suffix,
					config: Config{
						MaxVersion:             ver.version,
						SRTPProtectionProfiles: []uint16{40, SRTP_AES128_CM_HMAC_SHA1_80, 42},
					},
					flags: []string{
						"-srtp-profiles",
						"SRTP_AES128_CM_SHA1_80:SRTP_AES128_CM_SHA1_32",
					},
					expectations: connectionExpectations{
						srtpProtectionProfile: SRTP_AES128_CM_HMAC_SHA1_80,
					},
				})
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "SRTP-Server-" + suffix,
					config: Config{
						MaxVersion:             ver.version,
						SRTPProtectionProfiles: []uint16{40, SRTP_AES128_CM_HMAC_SHA1_80, 42},
					},
					flags: []string{
						"-srtp-profiles",
						"SRTP_AES128_CM_SHA1_80:SRTP_AES128_CM_SHA1_32",
					},
					expectations: connectionExpectations{
						srtpProtectionProfile: SRTP_AES128_CM_HMAC_SHA1_80,
					},
				})
				// Test that the MKI is ignored.
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "SRTP-Server-IgnoreMKI-" + suffix,
					config: Config{
						MaxVersion:             ver.version,
						SRTPProtectionProfiles: []uint16{SRTP_AES128_CM_HMAC_SHA1_80},
						Bugs: ProtocolBugs{
							SRTPMasterKeyIdentifier: "bogus",
						},
					},
					flags: []string{
						"-srtp-profiles",
						"SRTP_AES128_CM_SHA1_80:SRTP_AES128_CM_SHA1_32",
					},
					expectations: connectionExpectations{
						srtpProtectionProfile: SRTP_AES128_CM_HMAC_SHA1_80,
					},
				})
				// Test that SRTP isn't negotiated on the server if there were
				// no matching profiles.
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "SRTP-Server-NoMatch-" + suffix,
					config: Config{
						MaxVersion:             ver.version,
						SRTPProtectionProfiles: []uint16{100, 101, 102},
					},
					flags: []string{
						"-srtp-profiles",
						"SRTP_AES128_CM_SHA1_80:SRTP_AES128_CM_SHA1_32",
					},
					expectations: connectionExpectations{
						srtpProtectionProfile: 0,
					},
				})
				// Test that the server returning an invalid SRTP profile is
				// flagged as an error by the client.
				testCases = append(testCases, testCase{
					protocol: protocol,
					name:     "SRTP-Client-NoMatch-" + suffix,
					config: Config{
						MaxVersion: ver.version,
						Bugs: ProtocolBugs{
							SendSRTPProtectionProfile: SRTP_AES128_CM_HMAC_SHA1_32,
						},
					},
					flags: []string{
						"-srtp-profiles",
						"SRTP_AES128_CM_SHA1_80",
					},
					shouldFail:    true,
					expectedError: ":BAD_SRTP_PROTECTION_PROFILE_LIST:",
				})
			} else {
				// DTLS-SRTP is not defined for other protocols. Configuring it
				// on the client and server should ignore the extension.
				testCases = append(testCases, testCase{
					protocol: protocol,
					name:     "SRTP-Client-Ignore-" + suffix,
					config: Config{
						MaxVersion:             ver.version,
						SRTPProtectionProfiles: []uint16{40, SRTP_AES128_CM_HMAC_SHA1_80, 42},
					},
					flags: []string{
						"-srtp-profiles",
						"SRTP_AES128_CM_SHA1_80:SRTP_AES128_CM_SHA1_32",
					},
					expectations: connectionExpectations{
						srtpProtectionProfile: 0,
					},
				})
				testCases = append(testCases, testCase{
					protocol: protocol,
					testType: serverTest,
					name:     "SRTP-Server-Ignore-" + suffix,
					config: Config{
						MaxVersion:             ver.version,
						SRTPProtectionProfiles: []uint16{40, SRTP_AES128_CM_HMAC_SHA1_80, 42},
					},
					flags: []string{
						"-srtp-profiles",
						"SRTP_AES128_CM_SHA1_80:SRTP_AES128_CM_SHA1_32",
					},
					expectations: connectionExpectations{
						srtpProtectionProfile: 0,
					},
				})
			}

			// Test SCT list.
			testCases = append(testCases, testCase{
				protocol: protocol,
				name:     "SignedCertificateTimestampList-Client-" + suffix,
				testType: clientTest,
				config: Config{
					MaxVersion: ver.version,
					Credential: rsaCertificate.WithSCTList(testSCTList),
				},
				flags: []string{
					"-enable-signed-cert-timestamps",
					"-expect-signed-cert-timestamps",
					base64FlagValue(testSCTList),
				},
				resumeSession: true,
			})

			var differentSCTList []byte
			differentSCTList = append(differentSCTList, testSCTList...)
			differentSCTList[len(differentSCTList)-1] ^= 1

			// The SCT extension did not specify that it must only be sent on the inital handshake as it
			// should have, so test that we tolerate but ignore it. This is only an issue pre-1.3, since
			// SCTs are sent in the CertificateEntry message in 1.3, whereas they were previously sent
			// in an extension in the ServerHello pre-1.3.
			testCases = append(testCases, testCase{
				protocol: protocol,
				name:     "SendSCTListOnResume-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					Credential: rsaCertificate.WithSCTList(testSCTList),
					Bugs: ProtocolBugs{
						SendSCTListOnResume: differentSCTList,
					},
				},
				flags: []string{
					"-enable-signed-cert-timestamps",
					"-expect-signed-cert-timestamps",
					base64FlagValue(testSCTList),
				},
				resumeSession: true,
			})

			testCases = append(testCases, testCase{
				protocol: protocol,
				name:     "SignedCertificateTimestampList-Server-" + suffix,
				testType: serverTest,
				config: Config{
					MaxVersion: ver.version,
				},
				shimCertificate: rsaCertificate.WithSCTList(testSCTList),
				expectations: connectionExpectations{
					peerCertificate: rsaCertificate.WithSCTList(testSCTList),
				},
				resumeSession: true,
			})

			// Test empty SCT list.
			testCases = append(testCases, testCase{
				protocol: protocol,
				name:     "SignedCertificateTimestampListEmpty-Client-" + suffix,
				testType: clientTest,
				config: Config{
					MaxVersion: ver.version,
					Credential: rsaCertificate.WithSCTList([]byte{0, 0}),
				},
				flags: []string{
					"-enable-signed-cert-timestamps",
				},
				shouldFail:    true,
				expectedError: ":ERROR_PARSING_EXTENSION:",
			})

			// Test empty SCT in non-empty list.
			testCases = append(testCases, testCase{
				protocol: protocol,
				name:     "SignedCertificateTimestampListEmptySCT-Client-" + suffix,
				testType: clientTest,
				config: Config{
					MaxVersion: ver.version,
					Credential: rsaCertificate.WithSCTList([]byte{0, 6, 0, 2, 1, 2, 0, 0}),
				},
				flags: []string{
					"-enable-signed-cert-timestamps",
				},
				shouldFail:    true,
				expectedError: ":ERROR_PARSING_EXTENSION:",
			})

			// Test that certificate-related extensions are not sent unsolicited.
			testCases = append(testCases, testCase{
				protocol: protocol,
				testType: serverTest,
				name:     "UnsolicitedCertificateExtensions-" + suffix,
				config: Config{
					MaxVersion: ver.version,
					Bugs: ProtocolBugs{
						NoOCSPStapling:                true,
						NoSignedCertificateTimestamps: true,
					},
				},
				shimCertificate: rsaCertificate.WithOCSP(testOCSPResponse).WithSCTList(testSCTList),
			})

			// Extension permutation should interact correctly with other extensions,
			// HelloVerifyRequest, HelloRetryRequest, and ECH. SSLTest.PermuteExtensions
			// in ssl_test.cc tests that the extensions are actually permuted. This
			// tests the handshake still works.
			//
			// This test also tests that all our extensions interact with each other.
			for _, ech := range []bool{false, true} {
				if ech && ver.version < VersionTLS13 {
					continue
				}

				test := testCase{
					protocol:           protocol,
					name:               "AllExtensions-Client-Permute",
					skipQUICALPNConfig: true,
					config: Config{
						MinVersion:          ver.version,
						MaxVersion:          ver.version,
						Credential:          rsaCertificate.WithOCSP(testOCSPResponse).WithSCTList(testSCTList),
						NextProtos:          []string{"proto"},
						ApplicationSettings: map[string][]byte{"proto": []byte("runner1")},
						Bugs: ProtocolBugs{
							SendServerNameAck: true,
							ExpectServerName:  "example.com",
							ExpectGREASE:      true,
						},
					},
					resumeSession: true,
					flags: []string{
						"-permute-extensions",
						"-enable-grease",
						"-enable-ocsp-stapling",
						"-enable-signed-cert-timestamps",
						"-advertise-alpn", "\x05proto",
						"-expect-alpn", "proto",
						"-host-name", "example.com",
					},
				}

				if ech {
					test.name += "-ECH"
					echConfig := generateServerECHConfig(&ECHConfig{ConfigID: 42})
					test.config.ServerECHConfigs = []ServerECHConfig{echConfig}
					test.flags = append(test.flags,
						"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
						"-expect-ech-accept",
					)
					test.expectations.echAccepted = true
				}

				if ver.version >= VersionTLS13 {
					// Trigger a HelloRetryRequest to test both ClientHellos. Note
					// our DTLS tests always enable HelloVerifyRequest.
					test.name += "-HelloRetryRequest"

					// ALPS is only available on TLS 1.3.
					test.config.ApplicationSettings = map[string][]byte{"proto": []byte("runner")}
					test.flags = append(test.flags,
						"-application-settings", "proto,shim",
						"-alps-use-new-codepoint",
						"-expect-peer-application-settings", "runner")
					test.expectations.peerApplicationSettings = []byte("shim")
				}

				if protocol == dtls {
					test.config.SRTPProtectionProfiles = []uint16{SRTP_AES128_CM_HMAC_SHA1_80}
					test.flags = append(test.flags, "-srtp-profiles", "SRTP_AES128_CM_SHA1_80")
					test.expectations.srtpProtectionProfile = SRTP_AES128_CM_HMAC_SHA1_80
				}

				test.name += "-" + suffix
				testCases = append(testCases, test)
			}
		}
	}

	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "ClientHelloPadding",
		config: Config{
			Bugs: ProtocolBugs{
				RequireClientHelloSize: 512,
			},
		},
		// This hostname just needs to be long enough to push the
		// ClientHello into F5's danger zone between 256 and 511 bytes
		// long.
		flags: []string{"-host-name", "01234567890123456789012345678901234567890123456789012345678901234567890123456789.com"},
	})

	// Test that illegal extensions in TLS 1.3 are rejected by the client if
	// in ServerHello.
	testCases = append(testCases, testCase{
		name: "NPN-Forbidden-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			NextProtos: []string{"foo"},
			Bugs: ProtocolBugs{
				NegotiateNPNAtAllVersions: true,
			},
		},
		flags:         []string{"-select-next-proto", "foo"},
		shouldFail:    true,
		expectedError: ":ERROR_PARSING_EXTENSION:",
	})
	testCases = append(testCases, testCase{
		name: "EMS-Forbidden-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				NegotiateEMSAtAllVersions: true,
			},
		},
		shouldFail:    true,
		expectedError: ":ERROR_PARSING_EXTENSION:",
	})
	testCases = append(testCases, testCase{
		name: "RenegotiationInfo-Forbidden-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				NegotiateRenegotiationInfoAtAllVersions: true,
			},
		},
		shouldFail:    true,
		expectedError: ":ERROR_PARSING_EXTENSION:",
	})
	testCases = append(testCases, testCase{
		name: "Ticket-Forbidden-TLS13",
		config: Config{
			MaxVersion: VersionTLS12,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				AdvertiseTicketExtension: true,
			},
		},
		resumeSession: true,
		shouldFail:    true,
		expectedError: ":ERROR_PARSING_EXTENSION:",
	})

	// Test that illegal extensions in TLS 1.3 are declined by the server if
	// offered in ClientHello. The runner's server will fail if this occurs,
	// so we exercise the offering path. (EMS and Renegotiation Info are
	// implicit in every test.)
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "NPN-Declined-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			NextProtos: []string{"bar"},
		},
		flags: []string{"-advertise-npn", "\x03foo\x03bar\x03baz"},
	})

	// OpenSSL sends the status_request extension on resumption in TLS 1.2. Test that this is
	// tolerated.
	testCases = append(testCases, testCase{
		name: "SendOCSPResponseOnResume-TLS12",
		config: Config{
			MaxVersion: VersionTLS12,
			Credential: rsaCertificate.WithOCSP(testOCSPResponse),
			Bugs: ProtocolBugs{
				SendOCSPResponseOnResume: []byte("bogus"),
			},
		},
		flags: []string{
			"-enable-ocsp-stapling",
			"-expect-ocsp-response",
			base64FlagValue(testOCSPResponse),
		},
		resumeSession: true,
	})

	testCases = append(testCases, testCase{
		name: "SendUnsolicitedOCSPOnCertificate-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendExtensionOnCertificate: testOCSPExtension,
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_EXTENSION:",
	})

	testCases = append(testCases, testCase{
		name: "SendUnsolicitedSCTOnCertificate-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendExtensionOnCertificate: testSCTExtension,
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_EXTENSION:",
	})

	// Test that extensions on client certificates are never accepted.
	testCases = append(testCases, testCase{
		name:     "SendExtensionOnClientCertificate-TLS13",
		testType: serverTest,
		config: Config{
			MaxVersion: VersionTLS13,
			Credential: &rsaCertificate,
			Bugs: ProtocolBugs{
				SendExtensionOnCertificate: testOCSPExtension,
			},
		},
		flags: []string{
			"-enable-ocsp-stapling",
			"-require-any-client-certificate",
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_EXTENSION:",
	})

	testCases = append(testCases, testCase{
		name: "SendUnknownExtensionOnCertificate-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendExtensionOnCertificate: []byte{0x00, 0x7f, 0, 0},
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_EXTENSION:",
	})

	// Test that extensions on intermediates are allowed but ignored.
	testCases = append(testCases, testCase{
		name: "IgnoreExtensionsOnIntermediates-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Credential: rsaChainCertificate.WithOCSP(testOCSPResponse).WithSCTList(testSCTList),
			Bugs: ProtocolBugs{
				// Send different values on the intermediate. This tests
				// the intermediate's extensions do not override the
				// leaf's.
				SendOCSPOnIntermediates: testOCSPResponse2,
				SendSCTOnIntermediates:  testSCTList2,
			},
		},
		flags: []string{
			"-enable-ocsp-stapling",
			"-expect-ocsp-response",
			base64FlagValue(testOCSPResponse),
			"-enable-signed-cert-timestamps",
			"-expect-signed-cert-timestamps",
			base64FlagValue(testSCTList),
		},
		resumeSession: true,
	})

	// Test that extensions are not sent on intermediates when configured
	// only for a leaf.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SendNoExtensionsOnIntermediate-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				ExpectNoExtensionsOnIntermediate: true,
			},
		},
		shimCertificate: rsaChainCertificate.WithOCSP(testOCSPResponse).WithSCTList(testSCTList),
	})

	// Test that extensions are not sent on client certificates.
	testCases = append(testCases, testCase{
		name: "SendNoClientCertificateExtensions-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			ClientAuth: RequireAnyClientCert,
		},
		shimCertificate: rsaChainCertificate.WithOCSP(testOCSPResponse).WithSCTList(testSCTList),
	})

	testCases = append(testCases, testCase{
		name: "SendDuplicateExtensionsOnCerts-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Credential: rsaCertificate.WithOCSP(testOCSPResponse).WithSCTList(testSCTList),
			Bugs: ProtocolBugs{
				SendDuplicateCertExtensions: true,
			},
		},
		flags: []string{
			"-enable-ocsp-stapling",
			"-enable-signed-cert-timestamps",
		},
		resumeSession: true,
		shouldFail:    true,
		expectedError: ":DUPLICATE_EXTENSION:",
	})

	testCases = append(testCases, testCase{
		name:            "SignedCertificateTimestampListInvalid-Server",
		testType:        serverTest,
		shimCertificate: rsaCertificate.WithSCTList([]byte{0, 0}),
		shouldFail:      true,
		expectedError:   ":INVALID_SCT_LIST:",
	})
}

func addResumptionVersionTests() {
	for _, sessionVers := range tlsVersions {
		for _, resumeVers := range tlsVersions {
			protocols := []protocol{tls}
			if sessionVers.hasDTLS && resumeVers.hasDTLS {
				protocols = append(protocols, dtls)
			}
			if sessionVers.hasQUIC && resumeVers.hasQUIC {
				protocols = append(protocols, quic)
			}
			for _, protocol := range protocols {
				suffix := "-" + sessionVers.name + "-" + resumeVers.name
				suffix += "-" + protocol.String()

				if sessionVers.version == resumeVers.version {
					testCases = append(testCases, testCase{
						protocol:      protocol,
						name:          "Resume-Client" + suffix,
						resumeSession: true,
						config: Config{
							MaxVersion: sessionVers.version,
							Bugs: ProtocolBugs{
								ExpectNoTLS13PSK: sessionVers.version < VersionTLS13,
							},
						},
						expectations: connectionExpectations{
							version: sessionVers.version,
						},
						resumeExpectations: &connectionExpectations{
							version: resumeVers.version,
						},
					})
				} else if protocol != tls && sessionVers.version >= VersionTLS13 && resumeVers.version < VersionTLS13 {
					// In TLS 1.2 and below, the server indicates resumption by echoing
					// the client's session ID, which is impossible if the client did
					// not send a session ID. If the client offers a TLS 1.3 session, it
					// only fills in session ID in TLS (not DTLS or QUIC) for middlebox
					// compatibility mode. So, instead, test that the session ID was
					// empty and it was indeed impossible to hit this path
					testCases = append(testCases, testCase{
						protocol:      protocol,
						name:          "Resume-Client-Impossible" + suffix,
						resumeSession: true,
						config: Config{
							MaxVersion: sessionVers.version,
						},
						expectations: connectionExpectations{
							version: sessionVers.version,
						},
						resumeConfig: &Config{
							MaxVersion: resumeVers.version,
							Bugs: ProtocolBugs{
								ExpectNoSessionID: true,
							},
						},
						resumeExpectations: &connectionExpectations{
							version: resumeVers.version,
						},
						expectResumeRejected: true,
					})
				} else {
					// Test that the client rejects ServerHellos which resume
					// sessions at inconsistent versions.
					expectedError := ":OLD_SESSION_VERSION_NOT_RETURNED:"
					if sessionVers.version < VersionTLS13 && resumeVers.version >= VersionTLS13 {
						// The server will "resume" the session by sending pre_shared_key,
						// but the shim will not have sent pre_shared_key at all. The shim
						// should reject this because the extension was not allowed at all.
						expectedError = ":UNEXPECTED_EXTENSION:"
					}

					testCases = append(testCases, testCase{
						protocol:      protocol,
						name:          "Resume-Client-Mismatch" + suffix,
						resumeSession: true,
						config: Config{
							MaxVersion: sessionVers.version,
						},
						expectations: connectionExpectations{
							version: sessionVers.version,
						},
						resumeConfig: &Config{
							MaxVersion: resumeVers.version,
							Bugs: ProtocolBugs{
								AcceptAnySession: true,
							},
						},
						resumeExpectations: &connectionExpectations{
							version: resumeVers.version,
						},
						shouldFail:    true,
						expectedError: expectedError,
					})
				}

				testCases = append(testCases, testCase{
					protocol:      protocol,
					name:          "Resume-Client-NoResume" + suffix,
					resumeSession: true,
					config: Config{
						MaxVersion: sessionVers.version,
					},
					expectations: connectionExpectations{
						version: sessionVers.version,
					},
					resumeConfig: &Config{
						MaxVersion: resumeVers.version,
					},
					newSessionsOnResume:  true,
					expectResumeRejected: true,
					resumeExpectations: &connectionExpectations{
						version: resumeVers.version,
					},
				})

				testCases = append(testCases, testCase{
					protocol:      protocol,
					testType:      serverTest,
					name:          "Resume-Server" + suffix,
					resumeSession: true,
					config: Config{
						MaxVersion: sessionVers.version,
					},
					expectations: connectionExpectations{
						version: sessionVers.version,
					},
					expectResumeRejected: sessionVers != resumeVers,
					resumeConfig: &Config{
						MaxVersion: resumeVers.version,
						Bugs: ProtocolBugs{
							SendBothTickets: true,
						},
					},
					resumeExpectations: &connectionExpectations{
						version: resumeVers.version,
					},
				})

				// Repeat the test using session IDs, rather than tickets.
				if sessionVers.version < VersionTLS13 && resumeVers.version < VersionTLS13 {
					testCases = append(testCases, testCase{
						protocol:      protocol,
						testType:      serverTest,
						name:          "Resume-Server-NoTickets" + suffix,
						resumeSession: true,
						config: Config{
							MaxVersion:             sessionVers.version,
							SessionTicketsDisabled: true,
						},
						expectations: connectionExpectations{
							version: sessionVers.version,
						},
						expectResumeRejected: sessionVers != resumeVers,
						resumeConfig: &Config{
							MaxVersion:             resumeVers.version,
							SessionTicketsDisabled: true,
						},
						resumeExpectations: &connectionExpectations{
							version: resumeVers.version,
						},
					})
				}
			}
		}
	}

	// Make sure shim ticket mutations are functional.
	testCases = append(testCases, testCase{
		testType:      serverTest,
		name:          "ShimTicketRewritable",
		resumeSession: true,
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			Bugs: ProtocolBugs{
				FilterTicket: func(in []byte) ([]byte, error) {
					in, err := SetShimTicketVersion(in, VersionTLS12)
					if err != nil {
						return nil, err
					}
					return SetShimTicketCipherSuite(in, TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256)
				},
			},
		},
		flags: []string{
			"-ticket-key",
			base64FlagValue(TestShimTicketKey),
		},
	})

	// Resumptions are declined if the version does not match.
	testCases = append(testCases, testCase{
		testType:      serverTest,
		name:          "Resume-Server-DeclineCrossVersion",
		resumeSession: true,
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				ExpectNewTicket: true,
				FilterTicket: func(in []byte) ([]byte, error) {
					return SetShimTicketVersion(in, VersionTLS13)
				},
			},
		},
		flags: []string{
			"-ticket-key",
			base64FlagValue(TestShimTicketKey),
		},
		expectResumeRejected: true,
	})

	testCases = append(testCases, testCase{
		testType:      serverTest,
		name:          "Resume-Server-DeclineCrossVersion-TLS13",
		resumeSession: true,
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				FilterTicket: func(in []byte) ([]byte, error) {
					return SetShimTicketVersion(in, VersionTLS12)
				},
			},
		},
		flags: []string{
			"-ticket-key",
			base64FlagValue(TestShimTicketKey),
		},
		expectResumeRejected: true,
	})

	// Resumptions are declined if the cipher is invalid or disabled.
	testCases = append(testCases, testCase{
		testType:      serverTest,
		name:          "Resume-Server-DeclineBadCipher",
		resumeSession: true,
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				ExpectNewTicket: true,
				FilterTicket: func(in []byte) ([]byte, error) {
					return SetShimTicketCipherSuite(in, TLS_AES_128_GCM_SHA256)
				},
			},
		},
		flags: []string{
			"-ticket-key",
			base64FlagValue(TestShimTicketKey),
		},
		expectResumeRejected: true,
	})

	testCases = append(testCases, testCase{
		testType:      serverTest,
		name:          "Resume-Server-DeclineBadCipher-2",
		resumeSession: true,
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				ExpectNewTicket: true,
				FilterTicket: func(in []byte) ([]byte, error) {
					return SetShimTicketCipherSuite(in, TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384)
				},
			},
		},
		flags: []string{
			"-cipher", "AES128",
			"-ticket-key",
			base64FlagValue(TestShimTicketKey),
		},
		expectResumeRejected: true,
	})

	// Sessions are not resumed if they do not use the preferred cipher.
	testCases = append(testCases, testCase{
		testType:      serverTest,
		name:          "Resume-Server-CipherNotPreferred",
		resumeSession: true,
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				ExpectNewTicket: true,
				FilterTicket: func(in []byte) ([]byte, error) {
					return SetShimTicketCipherSuite(in, TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA)
				},
			},
		},
		flags: []string{
			"-ticket-key",
			base64FlagValue(TestShimTicketKey),
		},
		shouldFail:           false,
		expectResumeRejected: true,
	})

	// TLS 1.3 allows sessions to be resumed at a different cipher if their
	// PRF hashes match, but BoringSSL will always decline such resumptions.
	testCases = append(testCases, testCase{
		testType:      serverTest,
		name:          "Resume-Server-CipherNotPreferred-TLS13",
		resumeSession: true,
		config: Config{
			MaxVersion:   VersionTLS13,
			CipherSuites: []uint16{TLS_CHACHA20_POLY1305_SHA256, TLS_AES_128_GCM_SHA256},
			Bugs: ProtocolBugs{
				FilterTicket: func(in []byte) ([]byte, error) {
					// If the client (runner) offers ChaCha20-Poly1305 first, the
					// server (shim) always prefers it. Switch it to AES-GCM.
					return SetShimTicketCipherSuite(in, TLS_AES_128_GCM_SHA256)
				},
			},
		},
		flags: []string{
			"-ticket-key",
			base64FlagValue(TestShimTicketKey),
		},
		shouldFail:           false,
		expectResumeRejected: true,
	})

	// Sessions may not be resumed if they contain another version's cipher.
	testCases = append(testCases, testCase{
		testType:      serverTest,
		name:          "Resume-Server-DeclineBadCipher-TLS13",
		resumeSession: true,
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				FilterTicket: func(in []byte) ([]byte, error) {
					return SetShimTicketCipherSuite(in, TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256)
				},
			},
		},
		flags: []string{
			"-ticket-key",
			base64FlagValue(TestShimTicketKey),
		},
		expectResumeRejected: true,
	})

	// If the client does not offer the cipher from the session, decline to
	// resume. Clients are forbidden from doing this, but BoringSSL selects
	// the cipher first, so we only decline.
	testCases = append(testCases, testCase{
		testType:      serverTest,
		name:          "Resume-Server-UnofferedCipher",
		resumeSession: true,
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256},
		},
		resumeConfig: &Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256},
			Bugs: ProtocolBugs{
				SendCipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			},
		},
		expectResumeRejected: true,
	})

	// In TLS 1.3, clients may advertise a cipher list which does not
	// include the selected cipher. Test that we tolerate this. Servers may
	// resume at another cipher if the PRF matches and are not doing 0-RTT, but
	// BoringSSL will always decline.
	testCases = append(testCases, testCase{
		testType:      serverTest,
		name:          "Resume-Server-UnofferedCipher-TLS13",
		resumeSession: true,
		config: Config{
			MaxVersion:   VersionTLS13,
			CipherSuites: []uint16{TLS_CHACHA20_POLY1305_SHA256},
		},
		resumeConfig: &Config{
			MaxVersion:   VersionTLS13,
			CipherSuites: []uint16{TLS_CHACHA20_POLY1305_SHA256},
			Bugs: ProtocolBugs{
				SendCipherSuites: []uint16{TLS_AES_128_GCM_SHA256},
			},
		},
		expectResumeRejected: true,
	})

	// Sessions may not be resumed at a different cipher.
	testCases = append(testCases, testCase{
		name:          "Resume-Client-CipherMismatch",
		resumeSession: true,
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_RSA_WITH_AES_128_GCM_SHA256},
		},
		resumeConfig: &Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_RSA_WITH_AES_128_GCM_SHA256},
			Bugs: ProtocolBugs{
				SendCipherSuite: TLS_RSA_WITH_AES_128_CBC_SHA,
			},
		},
		shouldFail:    true,
		expectedError: ":OLD_SESSION_CIPHER_NOT_RETURNED:",
	})

	// Session resumption in TLS 1.3 may change the cipher suite if the PRF
	// matches.
	testCases = append(testCases, testCase{
		name:          "Resume-Client-CipherMismatch-TLS13",
		resumeSession: true,
		config: Config{
			MaxVersion:   VersionTLS13,
			CipherSuites: []uint16{TLS_AES_128_GCM_SHA256},
		},
		resumeConfig: &Config{
			MaxVersion:   VersionTLS13,
			CipherSuites: []uint16{TLS_CHACHA20_POLY1305_SHA256},
		},
	})

	// Session resumption in TLS 1.3 is forbidden if the PRF does not match.
	testCases = append(testCases, testCase{
		name:          "Resume-Client-PRFMismatch-TLS13",
		resumeSession: true,
		config: Config{
			MaxVersion:   VersionTLS13,
			CipherSuites: []uint16{TLS_AES_128_GCM_SHA256},
		},
		resumeConfig: &Config{
			MaxVersion:   VersionTLS13,
			CipherSuites: []uint16{TLS_AES_128_GCM_SHA256},
			Bugs: ProtocolBugs{
				SendCipherSuite: TLS_AES_256_GCM_SHA384,
			},
		},
		shouldFail:    true,
		expectedError: ":OLD_SESSION_PRF_HASH_MISMATCH:",
	})

	for _, secondBinder := range []bool{false, true} {
		var suffix string
		var defaultCurves []CurveID
		if secondBinder {
			suffix = "-SecondBinder"
			// Force a HelloRetryRequest by predicting an empty curve list.
			defaultCurves = []CurveID{}
		}

		testCases = append(testCases, testCase{
			testType:      serverTest,
			name:          "Resume-Server-BinderWrongLength" + suffix,
			resumeSession: true,
			config: Config{
				MaxVersion:    VersionTLS13,
				DefaultCurves: defaultCurves,
				Bugs: ProtocolBugs{
					SendShortPSKBinder:         true,
					OnlyCorruptSecondPSKBinder: secondBinder,
				},
			},
			shouldFail:         true,
			expectedLocalError: "remote error: error decrypting message",
			expectedError:      ":DIGEST_CHECK_FAILED:",
		})

		testCases = append(testCases, testCase{
			testType:      serverTest,
			name:          "Resume-Server-NoPSKBinder" + suffix,
			resumeSession: true,
			config: Config{
				MaxVersion:    VersionTLS13,
				DefaultCurves: defaultCurves,
				Bugs: ProtocolBugs{
					SendNoPSKBinder:            true,
					OnlyCorruptSecondPSKBinder: secondBinder,
				},
			},
			shouldFail:         true,
			expectedLocalError: "remote error: error decoding message",
			expectedError:      ":DECODE_ERROR:",
		})

		testCases = append(testCases, testCase{
			testType:      serverTest,
			name:          "Resume-Server-ExtraPSKBinder" + suffix,
			resumeSession: true,
			config: Config{
				MaxVersion:    VersionTLS13,
				DefaultCurves: defaultCurves,
				Bugs: ProtocolBugs{
					SendExtraPSKBinder:         true,
					OnlyCorruptSecondPSKBinder: secondBinder,
				},
			},
			shouldFail:         true,
			expectedLocalError: "remote error: illegal parameter",
			expectedError:      ":PSK_IDENTITY_BINDER_COUNT_MISMATCH:",
		})

		testCases = append(testCases, testCase{
			testType:      serverTest,
			name:          "Resume-Server-ExtraIdentityNoBinder" + suffix,
			resumeSession: true,
			config: Config{
				MaxVersion:    VersionTLS13,
				DefaultCurves: defaultCurves,
				Bugs: ProtocolBugs{
					ExtraPSKIdentity:           true,
					OnlyCorruptSecondPSKBinder: secondBinder,
				},
			},
			shouldFail:         true,
			expectedLocalError: "remote error: illegal parameter",
			expectedError:      ":PSK_IDENTITY_BINDER_COUNT_MISMATCH:",
		})

		testCases = append(testCases, testCase{
			testType:      serverTest,
			name:          "Resume-Server-InvalidPSKBinder" + suffix,
			resumeSession: true,
			config: Config{
				MaxVersion:    VersionTLS13,
				DefaultCurves: defaultCurves,
				Bugs: ProtocolBugs{
					SendInvalidPSKBinder:       true,
					OnlyCorruptSecondPSKBinder: secondBinder,
				},
			},
			shouldFail:         true,
			expectedLocalError: "remote error: error decrypting message",
			expectedError:      ":DIGEST_CHECK_FAILED:",
		})

		testCases = append(testCases, testCase{
			testType:      serverTest,
			name:          "Resume-Server-PSKBinderFirstExtension" + suffix,
			resumeSession: true,
			config: Config{
				MaxVersion:    VersionTLS13,
				DefaultCurves: defaultCurves,
				Bugs: ProtocolBugs{
					PSKBinderFirst:             true,
					OnlyCorruptSecondPSKBinder: secondBinder,
				},
			},
			shouldFail:         true,
			expectedLocalError: "remote error: illegal parameter",
			expectedError:      ":PRE_SHARED_KEY_MUST_BE_LAST:",
		})
	}

	testCases = append(testCases, testCase{
		testType:      serverTest,
		name:          "Resume-Server-OmitPSKsOnSecondClientHello",
		resumeSession: true,
		config: Config{
			MaxVersion:    VersionTLS13,
			DefaultCurves: []CurveID{},
			Bugs: ProtocolBugs{
				OmitPSKsOnSecondClientHello: true,
			},
		},
		shouldFail:         true,
		expectedLocalError: "remote error: illegal parameter",
		expectedError:      ":INCONSISTENT_CLIENT_HELLO:",
	})
}

func addRenegotiationTests() {
	// Servers cannot renegotiate.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "Renegotiate-Server-Forbidden",
		config: Config{
			MaxVersion: VersionTLS12,
		},
		renegotiate:        1,
		shouldFail:         true,
		expectedError:      ":NO_RENEGOTIATION:",
		expectedLocalError: "remote error: no renegotiation",
	})
	// The server shouldn't echo the renegotiation extension unless
	// requested by the client.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "Renegotiate-Server-NoExt",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				NoRenegotiationInfo:      true,
				RequireRenegotiationInfo: true,
			},
		},
		shouldFail:         true,
		expectedLocalError: "renegotiation extension missing",
	})
	// The renegotiation SCSV should be sufficient for the server to echo
	// the extension.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "Renegotiate-Server-NoExt-SCSV",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				NoRenegotiationInfo:      true,
				SendRenegotiationSCSV:    true,
				RequireRenegotiationInfo: true,
			},
		},
	})
	testCases = append(testCases, testCase{
		name: "Renegotiate-Client",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				FailIfResumeOnRenego: true,
			},
		},
		renegotiate: 1,
		// Test renegotiation after both an initial and resumption
		// handshake.
		resumeSession: true,
		flags: []string{
			"-renegotiate-freely",
			"-expect-total-renegotiations", "1",
			"-expect-secure-renegotiation",
		},
	})
	testCases = append(testCases, testCase{
		name: "Renegotiate-Client-TLS12",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				FailIfResumeOnRenego: true,
			},
		},
		renegotiate: 1,
		// Test renegotiation after both an initial and resumption
		// handshake.
		resumeSession: true,
		flags: []string{
			"-renegotiate-freely",
			"-expect-total-renegotiations", "1",
			"-expect-secure-renegotiation",
		},
	})
	testCases = append(testCases, testCase{
		name:        "Renegotiate-Client-EmptyExt",
		renegotiate: 1,
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				EmptyRenegotiationInfo: true,
			},
		},
		flags:              []string{"-renegotiate-freely"},
		shouldFail:         true,
		expectedError:      ":RENEGOTIATION_MISMATCH:",
		expectedLocalError: "handshake failure",
	})
	testCases = append(testCases, testCase{
		name:        "Renegotiate-Client-BadExt",
		renegotiate: 1,
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				BadRenegotiationInfo: true,
			},
		},
		flags:              []string{"-renegotiate-freely"},
		shouldFail:         true,
		expectedError:      ":RENEGOTIATION_MISMATCH:",
		expectedLocalError: "handshake failure",
	})
	testCases = append(testCases, testCase{
		name:        "Renegotiate-Client-BadExt2",
		renegotiate: 1,
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				BadRenegotiationInfoEnd: true,
			},
		},
		flags:              []string{"-renegotiate-freely"},
		shouldFail:         true,
		expectedError:      ":RENEGOTIATION_MISMATCH:",
		expectedLocalError: "handshake failure",
	})
	testCases = append(testCases, testCase{
		name:        "Renegotiate-Client-Downgrade",
		renegotiate: 1,
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				NoRenegotiationInfoAfterInitial: true,
			},
		},
		flags:              []string{"-renegotiate-freely"},
		shouldFail:         true,
		expectedError:      ":RENEGOTIATION_MISMATCH:",
		expectedLocalError: "handshake failure",
	})
	testCases = append(testCases, testCase{
		name:        "Renegotiate-Client-Upgrade",
		renegotiate: 1,
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				NoRenegotiationInfoInInitial: true,
			},
		},
		flags:              []string{"-renegotiate-freely"},
		shouldFail:         true,
		expectedError:      ":RENEGOTIATION_MISMATCH:",
		expectedLocalError: "handshake failure",
	})
	testCases = append(testCases, testCase{
		name:        "Renegotiate-Client-NoExt-Allowed",
		renegotiate: 1,
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				NoRenegotiationInfo: true,
			},
		},
		flags: []string{
			"-renegotiate-freely",
			"-expect-total-renegotiations", "1",
			"-expect-no-secure-renegotiation",
		},
	})

	// Test that the server may switch ciphers on renegotiation without
	// problems.
	testCases = append(testCases, testCase{
		name:        "Renegotiate-Client-SwitchCiphers",
		renegotiate: 1,
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_RSA_WITH_AES_128_CBC_SHA},
		},
		renegotiateCiphers: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
		flags: []string{
			"-renegotiate-freely",
			"-expect-total-renegotiations", "1",
		},
	})
	testCases = append(testCases, testCase{
		name:        "Renegotiate-Client-SwitchCiphers2",
		renegotiate: 1,
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
		},
		renegotiateCiphers: []uint16{TLS_RSA_WITH_AES_128_CBC_SHA},
		flags: []string{
			"-renegotiate-freely",
			"-expect-total-renegotiations", "1",
		},
	})

	// Test that the server may not switch versions on renegotiation.
	testCases = append(testCases, testCase{
		name: "Renegotiate-Client-SwitchVersion",
		config: Config{
			MaxVersion: VersionTLS12,
			// Pick a cipher which exists at both versions.
			CipherSuites: []uint16{TLS_RSA_WITH_AES_128_CBC_SHA},
			Bugs: ProtocolBugs{
				NegotiateVersionOnRenego: VersionTLS11,
				// Avoid failing early at the record layer.
				SendRecordVersion: VersionTLS12,
			},
		},
		renegotiate: 1,
		flags: []string{
			"-renegotiate-freely",
			"-expect-total-renegotiations", "1",
		},
		shouldFail:    true,
		expectedError: ":WRONG_SSL_VERSION:",
	})

	testCases = append(testCases, testCase{
		name:        "Renegotiate-SameClientVersion",
		renegotiate: 1,
		config: Config{
			MaxVersion: VersionTLS10,
			Bugs: ProtocolBugs{
				RequireSameRenegoClientVersion: true,
			},
		},
		flags: []string{
			"-renegotiate-freely",
			"-expect-total-renegotiations", "1",
		},
	})
	testCases = append(testCases, testCase{
		name:        "Renegotiate-FalseStart",
		renegotiate: 1,
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			NextProtos:   []string{"foo"},
		},
		flags: []string{
			"-false-start",
			"-select-next-proto", "foo",
			"-renegotiate-freely",
			"-expect-total-renegotiations", "1",
		},
		shimWritesFirst: true,
	})

	// Client-side renegotiation controls.
	testCases = append(testCases, testCase{
		name: "Renegotiate-Client-Forbidden-1",
		config: Config{
			MaxVersion: VersionTLS12,
		},
		renegotiate:        1,
		shouldFail:         true,
		expectedError:      ":NO_RENEGOTIATION:",
		expectedLocalError: "remote error: no renegotiation",
	})
	testCases = append(testCases, testCase{
		name: "Renegotiate-Client-Once-1",
		config: Config{
			MaxVersion: VersionTLS12,
		},
		renegotiate: 1,
		flags: []string{
			"-renegotiate-once",
			"-expect-total-renegotiations", "1",
		},
	})
	testCases = append(testCases, testCase{
		name: "Renegotiate-Client-Freely-1",
		config: Config{
			MaxVersion: VersionTLS12,
		},
		renegotiate: 1,
		flags: []string{
			"-renegotiate-freely",
			"-expect-total-renegotiations", "1",
		},
	})
	testCases = append(testCases, testCase{
		name: "Renegotiate-Client-Once-2",
		config: Config{
			MaxVersion: VersionTLS12,
		},
		renegotiate:        2,
		flags:              []string{"-renegotiate-once"},
		shouldFail:         true,
		expectedError:      ":NO_RENEGOTIATION:",
		expectedLocalError: "remote error: no renegotiation",
	})
	testCases = append(testCases, testCase{
		name: "Renegotiate-Client-Freely-2",
		config: Config{
			MaxVersion: VersionTLS12,
		},
		renegotiate: 2,
		flags: []string{
			"-renegotiate-freely",
			"-expect-total-renegotiations", "2",
		},
	})
	testCases = append(testCases, testCase{
		name: "Renegotiate-Client-NoIgnore",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SendHelloRequestBeforeEveryAppDataRecord: true,
			},
		},
		shouldFail:    true,
		expectedError: ":NO_RENEGOTIATION:",
	})
	testCases = append(testCases, testCase{
		name: "Renegotiate-Client-Ignore",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SendHelloRequestBeforeEveryAppDataRecord: true,
			},
		},
		flags: []string{
			"-renegotiate-ignore",
			"-expect-total-renegotiations", "0",
		},
	})

	// Renegotiation may be enabled and then disabled immediately after the
	// handshake.
	testCases = append(testCases, testCase{
		name: "Renegotiate-ForbidAfterHandshake",
		config: Config{
			MaxVersion: VersionTLS12,
		},
		renegotiate:        1,
		flags:              []string{"-forbid-renegotiation-after-handshake"},
		shouldFail:         true,
		expectedError:      ":NO_RENEGOTIATION:",
		expectedLocalError: "remote error: no renegotiation",
	})

	// Renegotiation is not allowed when there is an unfinished write.
	testCases = append(testCases, testCase{
		name: "Renegotiate-Client-UnfinishedWrite",
		config: Config{
			MaxVersion: VersionTLS12,
		},
		renegotiate:             1,
		readWithUnfinishedWrite: true,
		flags: []string{
			"-async",
			"-renegotiate-freely",
		},
		shouldFail:    true,
		expectedError: ":NO_RENEGOTIATION:",
		// We do not successfully send the no_renegotiation alert in
		// this case. https://crbug.com/boringssl/130
	})

	// We reject stray HelloRequests during the handshake in TLS 1.2.
	testCases = append(testCases, testCase{
		name: "StrayHelloRequest",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SendHelloRequestBeforeEveryHandshakeMessage: true,
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_MESSAGE:",
	})
	testCases = append(testCases, testCase{
		name: "StrayHelloRequest-Packed",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				PackHandshakeFlight:                         true,
				SendHelloRequestBeforeEveryHandshakeMessage: true,
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_MESSAGE:",
	})

	// Test that HelloRequest is rejected if it comes in the same record as the
	// server Finished.
	testCases = append(testCases, testCase{
		name: "Renegotiate-Client-Packed",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				PackHandshakeFlight:          true,
				PackHelloRequestWithFinished: true,
			},
		},
		renegotiate:        1,
		flags:              []string{"-renegotiate-freely"},
		shouldFail:         true,
		expectedError:      ":EXCESS_HANDSHAKE_DATA:",
		expectedLocalError: "remote error: unexpected message",
	})

	// Renegotiation is forbidden in TLS 1.3.
	testCases = append(testCases, testCase{
		name: "Renegotiate-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendHelloRequestBeforeEveryAppDataRecord: true,
			},
		},
		flags: []string{
			"-renegotiate-freely",
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_MESSAGE:",
	})

	// Stray HelloRequests during the handshake are forbidden in TLS 1.3.
	testCases = append(testCases, testCase{
		name: "StrayHelloRequest-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendHelloRequestBeforeEveryHandshakeMessage: true,
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_MESSAGE:",
	})

	// The renegotiation_info extension is not sent in TLS 1.3, but TLS 1.3
	// always reads as supporting it, regardless of whether it was
	// negotiated.
	testCases = append(testCases, testCase{
		name: "AlwaysReportRenegotiationInfo-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				NoRenegotiationInfo: true,
			},
		},
		flags: []string{
			"-expect-secure-renegotiation",
		},
	})

	// Certificates may not change on renegotiation.
	testCases = append(testCases, testCase{
		name: "Renegotiation-CertificateChange",
		config: Config{
			MaxVersion: VersionTLS12,
			Credential: &rsaCertificate,
			Bugs: ProtocolBugs{
				RenegotiationCertificate: &rsaChainCertificate,
			},
		},
		renegotiate:   1,
		flags:         []string{"-renegotiate-freely"},
		shouldFail:    true,
		expectedError: ":SERVER_CERT_CHANGED:",
	})
	testCases = append(testCases, testCase{
		name: "Renegotiation-CertificateChange-2",
		config: Config{
			MaxVersion: VersionTLS12,
			Credential: &rsaCertificate,
			Bugs: ProtocolBugs{
				RenegotiationCertificate: &rsa1024Certificate,
			},
		},
		renegotiate:   1,
		flags:         []string{"-renegotiate-freely"},
		shouldFail:    true,
		expectedError: ":SERVER_CERT_CHANGED:",
	})

	// We do not negotiate ALPN after the initial handshake. This is
	// error-prone and only risks bugs in consumers.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "Renegotiation-ForbidALPN",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				// Forcibly negotiate ALPN on both initial and
				// renegotiation handshakes. The test stack will
				// internally check the client does not offer
				// it.
				SendALPN: "foo",
			},
		},
		flags: []string{
			"-advertise-alpn", "\x03foo\x03bar\x03baz",
			"-expect-alpn", "foo",
			"-renegotiate-freely",
		},
		renegotiate:   1,
		shouldFail:    true,
		expectedError: ":UNEXPECTED_EXTENSION:",
	})

	// The server may send different stapled OCSP responses or SCT lists on
	// renegotiation, but BoringSSL ignores this and reports the old values.
	// Also test that non-fatal verify results are preserved.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "Renegotiation-ChangeAuthProperties",
		config: Config{
			MaxVersion: VersionTLS12,
			Credential: rsaCertificate.WithOCSP(testOCSPResponse).WithSCTList(testSCTList),
			Bugs: ProtocolBugs{
				SendOCSPResponseOnRenegotiation: testOCSPResponse2,
				SendSCTListOnRenegotiation:      testSCTList2,
			},
		},
		renegotiate: 1,
		flags: []string{
			"-renegotiate-freely",
			"-expect-total-renegotiations", "1",
			"-enable-ocsp-stapling",
			"-expect-ocsp-response",
			base64FlagValue(testOCSPResponse),
			"-enable-signed-cert-timestamps",
			"-expect-signed-cert-timestamps",
			base64FlagValue(testSCTList),
			"-verify-fail",
			"-expect-verify-result",
		},
	})
}

func addDTLSReplayTests() {
	for _, vers := range allVersions(dtls) {
		// Test that sequence number replays are detected.
		testCases = append(testCases, testCase{
			protocol: dtls,
			name:     "DTLS-Replay-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
			},
			messageCount: 200,
			replayWrites: true,
		})

		// Test the incoming sequence number skipping by values larger
		// than the retransmit window.
		testCases = append(testCases, testCase{
			protocol: dtls,
			name:     "DTLS-Replay-LargeGaps-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
				Bugs: ProtocolBugs{
					SequenceNumberMapping: func(in uint64) uint64 {
						return in * 1023
					},
				},
			},
			messageCount: 200,
			replayWrites: true,
		})

		// Test the incoming sequence number changing non-monotonically.
		testCases = append(testCases, testCase{
			protocol: dtls,
			name:     "DTLS-Replay-NonMonotonic-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
				Bugs: ProtocolBugs{
					SequenceNumberMapping: func(in uint64) uint64 {
						// This mapping has numbers counting backwards in groups
						// of 256, and then jumping forwards 511 numbers.
						return in ^ 255
					},
				},
			},
			// This messageCount is large enough to make sure that the SequenceNumberMapping
			// will reach the point where it jumps forwards after stepping backwards.
			messageCount: 500,
			replayWrites: true,
		})
	}
}

var testSignatureAlgorithms = []struct {
	name     string
	id       signatureAlgorithm
	baseCert *Credential
	// If non-zero, the curve that must be supported in TLS 1.2 for cert to be
	// accepted.
	curve CurveID
}{
	{"RSA_PKCS1_SHA1", signatureRSAPKCS1WithSHA1, &rsaCertificate, 0},
	{"RSA_PKCS1_SHA256", signatureRSAPKCS1WithSHA256, &rsaCertificate, 0},
	{"RSA_PKCS1_SHA256_LEGACY", signatureRSAPKCS1WithSHA256Legacy, &rsaCertificate, 0},
	{"RSA_PKCS1_SHA384", signatureRSAPKCS1WithSHA384, &rsaCertificate, 0},
	{"RSA_PKCS1_SHA512", signatureRSAPKCS1WithSHA512, &rsaCertificate, 0},
	{"ECDSA_SHA1", signatureECDSAWithSHA1, &ecdsaP256Certificate, CurveP256},
	// The “P256” in the following line is not a mistake. In TLS 1.2 the
	// hash function doesn't have to match the curve and so the same
	// signature algorithm works with P-224.
	{"ECDSA_P224_SHA256", signatureECDSAWithP256AndSHA256, &ecdsaP224Certificate, CurveP224},
	{"ECDSA_P256_SHA256", signatureECDSAWithP256AndSHA256, &ecdsaP256Certificate, CurveP256},
	{"ECDSA_P384_SHA384", signatureECDSAWithP384AndSHA384, &ecdsaP384Certificate, CurveP384},
	{"ECDSA_P521_SHA512", signatureECDSAWithP521AndSHA512, &ecdsaP521Certificate, CurveP521},
	{"RSA_PSS_SHA256", signatureRSAPSSWithSHA256, &rsaCertificate, 0},
	{"RSA_PSS_SHA384", signatureRSAPSSWithSHA384, &rsaCertificate, 0},
	{"RSA_PSS_SHA512", signatureRSAPSSWithSHA512, &rsaCertificate, 0},
	{"Ed25519", signatureEd25519, &ed25519Certificate, 0},
	// Tests for key types prior to TLS 1.2.
	{"RSA", 0, &rsaCertificate, 0},
	{"ECDSA", 0, &ecdsaP256Certificate, CurveP256},
}

const (
	fakeSigAlg1 signatureAlgorithm = 0x2a01
	fakeSigAlg2 signatureAlgorithm = 0xff01
)

func addSignatureAlgorithmTests() {
	// Not all ciphers involve a signature. Advertise a list which gives all
	// versions a signing cipher.
	signingCiphers := []uint16{
		TLS_AES_256_GCM_SHA384,
		TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
		TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
		TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
		TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
	}

	var allAlgorithms []signatureAlgorithm
	for _, alg := range testSignatureAlgorithms {
		if alg.id != 0 {
			allAlgorithms = append(allAlgorithms, alg.id)
		}
	}

	// Make sure each signature algorithm works. Include some fake values in
	// the list and ensure they're ignored.
	for _, alg := range testSignatureAlgorithms {
		// Make a version of the certificate that will not sign any other algorithm.
		cert := alg.baseCert
		if alg.id != 0 {
			cert = cert.WithSignatureAlgorithms(alg.id)
		}

		for _, ver := range tlsVersions {
			if (ver.version < VersionTLS12) != (alg.id == 0) {
				continue
			}

			suffix := "-" + alg.name + "-" + ver.name
			for _, signTestType := range []testType{clientTest, serverTest} {
				signPrefix := "Client-"
				verifyPrefix := "Server-"
				verifyTestType := serverTest
				if signTestType == serverTest {
					verifyTestType = clientTest
					signPrefix, verifyPrefix = verifyPrefix, signPrefix
				}

				var shouldFail bool
				isTLS12PKCS1 := hasComponent(alg.name, "PKCS1") && !hasComponent(alg.name, "LEGACY")
				isTLS13PKCS1 := hasComponent(alg.name, "PKCS1") && hasComponent(alg.name, "LEGACY")

				// TLS 1.3 removes a number of signature algorithms.
				if ver.version >= VersionTLS13 && (alg.curve == CurveP224 || alg.id == signatureECDSAWithSHA1 || isTLS12PKCS1) {
					shouldFail = true
				}

				// The backported RSA-PKCS1 code points only exist for TLS 1.3
				// client certificates.
				if (ver.version < VersionTLS13 || signTestType == serverTest) && isTLS13PKCS1 {
					shouldFail = true
				}

				// By default, BoringSSL does not sign with these algorithms.
				signDefault := !shouldFail
				if isTLS13PKCS1 {
					signDefault = false
				}

				// By default, BoringSSL does not accept these algorithms.
				verifyDefault := !shouldFail
				if alg.id == signatureECDSAWithSHA1 || alg.id == signatureECDSAWithP521AndSHA512 || alg.id == signatureEd25519 || isTLS13PKCS1 {
					verifyDefault = false
				}

				var curveFlags []string
				var runnerCurves []CurveID
				if alg.curve != 0 && ver.version <= VersionTLS12 {
					// In TLS 1.2, the ECDH curve list also constrains ECDSA keys. Ensure the
					// corresponding curve is enabled. Also include X25519 to ensure the shim
					// and runner have something in common for ECDH.
					curveFlags = flagInts("-curves", []int{int(CurveX25519), int(alg.curve)})
					runnerCurves = []CurveID{CurveX25519, alg.curve}
				}

				signError := func(shouldFail bool) string {
					if !shouldFail {
						return ""
					}
					// In TLS 1.3, the shim should report no common signature algorithms if
					// it cannot generate a signature. In TLS 1.2 servers, signature
					// algorithm and cipher selection are integrated, so it is reported as
					// no shared cipher.
					if ver.version <= VersionTLS12 && signTestType == serverTest {
						return ":NO_SHARED_CIPHER:"
					}
					return ":NO_COMMON_SIGNATURE_ALGORITHMS:"
				}
				signLocalError := func(shouldFail bool) string {
					if !shouldFail {
						return ""
					}
					// The shim should send handshake_failure when it cannot
					// negotiate parameters.
					return "remote error: handshake failure"
				}
				verifyError := func(shouldFail bool) string {
					if !shouldFail {
						return ""
					}
					// If the shim rejects the signature algorithm, but the
					// runner forcibly selects it anyway, the shim should notice.
					return ":WRONG_SIGNATURE_TYPE:"
				}
				verifyLocalError := func(shouldFail bool) string {
					if !shouldFail {
						return ""
					}
					// The shim should send an illegal_parameter alert if the runner
					// uses a signature algorithm it isn't allowed to use.
					return "remote error: illegal parameter"
				}

				// Test the shim using the algorithm for signing.
				signTest := testCase{
					testType: signTestType,
					name:     signPrefix + "Sign" + suffix,
					config: Config{
						MaxVersion:       ver.version,
						CurvePreferences: runnerCurves,
						VerifySignatureAlgorithms: []signatureAlgorithm{
							fakeSigAlg1,
							alg.id,
							fakeSigAlg2,
						},
					},
					shimCertificate:    cert,
					flags:              curveFlags,
					shouldFail:         shouldFail,
					expectedError:      signError(shouldFail),
					expectedLocalError: signLocalError(shouldFail),
					expectations: connectionExpectations{
						peerSignatureAlgorithm: alg.id,
					},
				}

				// Test whether the shim enables the algorithm by default.
				signDefaultTest := testCase{
					testType: signTestType,
					name:     signPrefix + "SignDefault" + suffix,
					config: Config{
						MaxVersion:       ver.version,
						CurvePreferences: runnerCurves,
						VerifySignatureAlgorithms: []signatureAlgorithm{
							fakeSigAlg1,
							alg.id,
							fakeSigAlg2,
						},
					},
					// cert has been configured with the specified algorithm,
					// while alg.baseCert uses the defaults.
					shimCertificate:    alg.baseCert,
					flags:              curveFlags,
					shouldFail:         !signDefault,
					expectedError:      signError(!signDefault),
					expectedLocalError: signLocalError(!signDefault),
					expectations: connectionExpectations{
						peerSignatureAlgorithm: alg.id,
					},
				}

				// Test that the shim will select the algorithm when configured to only
				// support it.
				negotiateTest := testCase{
					testType: signTestType,
					name:     signPrefix + "Sign-Negotiate" + suffix,
					config: Config{
						MaxVersion:                ver.version,
						CurvePreferences:          runnerCurves,
						VerifySignatureAlgorithms: allAlgorithms,
					},
					shimCertificate: cert,
					flags:           curveFlags,
					expectations: connectionExpectations{
						peerSignatureAlgorithm: alg.id,
					},
				}

				if signTestType == serverTest {
					// TLS 1.2 servers only sign on some cipher suites.
					signTest.config.CipherSuites = signingCiphers
					signDefaultTest.config.CipherSuites = signingCiphers
					negotiateTest.config.CipherSuites = signingCiphers
				} else {
					// TLS 1.2 clients only sign when the server requests certificates.
					signTest.config.ClientAuth = RequireAnyClientCert
					signDefaultTest.config.ClientAuth = RequireAnyClientCert
					negotiateTest.config.ClientAuth = RequireAnyClientCert
				}
				testCases = append(testCases, signTest, signDefaultTest)
				if ver.version >= VersionTLS12 && !shouldFail {
					testCases = append(testCases, negotiateTest)
				}

				// Test the shim using the algorithm for verifying.
				verifyTest := testCase{
					testType: verifyTestType,
					name:     verifyPrefix + "Verify" + suffix,
					config: Config{
						MaxVersion: ver.version,
						Credential: cert,
						Bugs: ProtocolBugs{
							SkipECDSACurveCheck:          shouldFail,
							IgnoreSignatureVersionChecks: shouldFail,
							// Some signature algorithms may not be advertised.
							IgnorePeerSignatureAlgorithmPreferences: shouldFail,
						},
					},
					flags: curveFlags,
					// Resume the session to assert the peer signature
					// algorithm is reported on both handshakes.
					resumeSession:      !shouldFail,
					shouldFail:         shouldFail,
					expectedError:      verifyError(shouldFail),
					expectedLocalError: verifyLocalError(shouldFail),
				}
				if alg.id != 0 {
					verifyTest.flags = append(verifyTest.flags, "-expect-peer-signature-algorithm", strconv.Itoa(int(alg.id)))
					// The algorithm may be disabled by default, so explicitly enable it.
					verifyTest.flags = append(verifyTest.flags, "-verify-prefs", strconv.Itoa(int(alg.id)))
				}

				// Test whether the shim expects the algorithm enabled by default.
				defaultTest := testCase{
					testType: verifyTestType,
					name:     verifyPrefix + "VerifyDefault" + suffix,
					config: Config{
						MaxVersion: ver.version,
						Credential: cert,
						Bugs: ProtocolBugs{
							SkipECDSACurveCheck:          !verifyDefault,
							IgnoreSignatureVersionChecks: !verifyDefault,
							// Some signature algorithms may not be advertised.
							IgnorePeerSignatureAlgorithmPreferences: !verifyDefault,
						},
					},
					flags: append(
						[]string{"-expect-peer-signature-algorithm", strconv.Itoa(int(alg.id))},
						curveFlags...,
					),
					// Resume the session to assert the peer signature
					// algorithm is reported on both handshakes.
					resumeSession:      verifyDefault,
					shouldFail:         !verifyDefault,
					expectedError:      verifyError(!verifyDefault),
					expectedLocalError: verifyLocalError(!verifyDefault),
				}

				// Test whether the shim handles invalid signatures for this algorithm.
				invalidTest := testCase{
					testType: verifyTestType,
					name:     verifyPrefix + "InvalidSignature" + suffix,
					config: Config{
						MaxVersion: ver.version,
						Credential: cert,
						Bugs: ProtocolBugs{
							InvalidSignature: true,
						},
					},
					flags:         curveFlags,
					shouldFail:    true,
					expectedError: ":BAD_SIGNATURE:",
				}
				if alg.id != 0 {
					// The algorithm may be disabled by default, so explicitly enable it.
					invalidTest.flags = append(invalidTest.flags, "-verify-prefs", strconv.Itoa(int(alg.id)))
				}

				if verifyTestType == serverTest {
					// TLS 1.2 servers only verify when they request client certificates.
					verifyTest.flags = append(verifyTest.flags, "-require-any-client-certificate")
					defaultTest.flags = append(defaultTest.flags, "-require-any-client-certificate")
					invalidTest.flags = append(invalidTest.flags, "-require-any-client-certificate")
				} else {
					// TLS 1.2 clients only verify on some cipher suites.
					verifyTest.config.CipherSuites = signingCiphers
					defaultTest.config.CipherSuites = signingCiphers
					invalidTest.config.CipherSuites = signingCiphers
				}
				testCases = append(testCases, verifyTest, defaultTest)
				if !shouldFail {
					testCases = append(testCases, invalidTest)
				}
			}
		}
	}

	// Test the peer's verify preferences are available.
	for _, ver := range tlsVersions {
		if ver.version < VersionTLS12 {
			continue
		}
		testCases = append(testCases, testCase{
			name: "ClientAuth-PeerVerifyPrefs-" + ver.name,
			config: Config{
				MaxVersion: ver.version,
				ClientAuth: RequireAnyClientCert,
				VerifySignatureAlgorithms: []signatureAlgorithm{
					signatureRSAPSSWithSHA256,
					signatureEd25519,
					signatureECDSAWithP256AndSHA256,
				},
			},
			shimCertificate: &rsaCertificate,
			flags: []string{
				"-expect-peer-verify-pref", strconv.Itoa(int(signatureRSAPSSWithSHA256)),
				"-expect-peer-verify-pref", strconv.Itoa(int(signatureEd25519)),
				"-expect-peer-verify-pref", strconv.Itoa(int(signatureECDSAWithP256AndSHA256)),
			},
		})

		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "ServerAuth-PeerVerifyPrefs-" + ver.name,
			config: Config{
				MaxVersion: ver.version,
				VerifySignatureAlgorithms: []signatureAlgorithm{
					signatureRSAPSSWithSHA256,
					signatureEd25519,
					signatureECDSAWithP256AndSHA256,
				},
			},
			shimCertificate: &rsaCertificate,
			flags: []string{
				"-expect-peer-verify-pref", strconv.Itoa(int(signatureRSAPSSWithSHA256)),
				"-expect-peer-verify-pref", strconv.Itoa(int(signatureEd25519)),
				"-expect-peer-verify-pref", strconv.Itoa(int(signatureECDSAWithP256AndSHA256)),
			},
		})

	}

	// Test that algorithm selection takes the key type into account.
	testCases = append(testCases, testCase{
		name: "ClientAuth-SignatureType",
		config: Config{
			ClientAuth: RequireAnyClientCert,
			MaxVersion: VersionTLS12,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureECDSAWithP521AndSHA512,
				signatureRSAPKCS1WithSHA384,
				signatureECDSAWithSHA1,
			},
		},
		shimCertificate: &rsaCertificate,
		expectations: connectionExpectations{
			peerSignatureAlgorithm: signatureRSAPKCS1WithSHA384,
		},
	})

	testCases = append(testCases, testCase{
		name: "ClientAuth-SignatureType-TLS13",
		config: Config{
			ClientAuth: RequireAnyClientCert,
			MaxVersion: VersionTLS13,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureECDSAWithP521AndSHA512,
				signatureRSAPKCS1WithSHA384,
				signatureRSAPSSWithSHA384,
				signatureECDSAWithSHA1,
			},
		},
		shimCertificate: &rsaCertificate,
		expectations: connectionExpectations{
			peerSignatureAlgorithm: signatureRSAPSSWithSHA384,
		},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ServerAuth-SignatureType",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureECDSAWithP521AndSHA512,
				signatureRSAPKCS1WithSHA384,
				signatureECDSAWithSHA1,
			},
		},
		expectations: connectionExpectations{
			peerSignatureAlgorithm: signatureRSAPKCS1WithSHA384,
		},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ServerAuth-SignatureType-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureECDSAWithP521AndSHA512,
				signatureRSAPKCS1WithSHA384,
				signatureRSAPSSWithSHA384,
				signatureECDSAWithSHA1,
			},
		},
		expectations: connectionExpectations{
			peerSignatureAlgorithm: signatureRSAPSSWithSHA384,
		},
	})

	// Test that signature verification takes the key type into account.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "Verify-ClientAuth-SignatureType",
		config: Config{
			MaxVersion: VersionTLS12,
			Credential: rsaCertificate.WithSignatureAlgorithms(signatureRSAPKCS1WithSHA256),
			Bugs: ProtocolBugs{
				SendSignatureAlgorithm: signatureECDSAWithP256AndSHA256,
			},
		},
		flags: []string{
			"-require-any-client-certificate",
		},
		shouldFail:    true,
		expectedError: ":WRONG_SIGNATURE_TYPE:",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "Verify-ClientAuth-SignatureType-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Credential: rsaCertificate.WithSignatureAlgorithms(signatureRSAPSSWithSHA256),
			Bugs: ProtocolBugs{
				SendSignatureAlgorithm: signatureECDSAWithP256AndSHA256,
			},
		},
		flags: []string{
			"-require-any-client-certificate",
		},
		shouldFail:    true,
		expectedError: ":WRONG_SIGNATURE_TYPE:",
	})

	testCases = append(testCases, testCase{
		name: "Verify-ServerAuth-SignatureType",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			Credential:   rsaCertificate.WithSignatureAlgorithms(signatureRSAPKCS1WithSHA256),
			Bugs: ProtocolBugs{
				SendSignatureAlgorithm: signatureECDSAWithP256AndSHA256,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_SIGNATURE_TYPE:",
	})

	testCases = append(testCases, testCase{
		name: "Verify-ServerAuth-SignatureType-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Credential: rsaCertificate.WithSignatureAlgorithms(signatureRSAPSSWithSHA256),
			Bugs: ProtocolBugs{
				SendSignatureAlgorithm: signatureECDSAWithP256AndSHA256,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_SIGNATURE_TYPE:",
	})

	// Test that, if the ClientHello list is missing, the server falls back
	// to SHA-1 in TLS 1.2, but not TLS 1.3.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ServerAuth-SHA1-Fallback-RSA",
		config: Config{
			MaxVersion: VersionTLS12,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureRSAPKCS1WithSHA1,
			},
			Bugs: ProtocolBugs{
				NoSignatureAlgorithms: true,
			},
		},
		shimCertificate: &rsaCertificate,
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ServerAuth-SHA1-Fallback-ECDSA",
		config: Config{
			MaxVersion: VersionTLS12,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureECDSAWithSHA1,
			},
			Bugs: ProtocolBugs{
				NoSignatureAlgorithms: true,
			},
		},
		shimCertificate: &ecdsaP256Certificate,
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ServerAuth-NoFallback-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureRSAPKCS1WithSHA1,
			},
			Bugs: ProtocolBugs{
				NoSignatureAlgorithms: true,
			},
		},
		shouldFail:    true,
		expectedError: ":NO_COMMON_SIGNATURE_ALGORITHMS:",
	})

	// The CertificateRequest list, however, may never be omitted. It is a
	// syntax error for it to be empty.
	testCases = append(testCases, testCase{
		name: "ClientAuth-NoFallback-RSA",
		config: Config{
			MaxVersion: VersionTLS12,
			ClientAuth: RequireAnyClientCert,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureRSAPKCS1WithSHA1,
			},
			Bugs: ProtocolBugs{
				NoSignatureAlgorithms: true,
			},
		},
		shimCertificate:    &rsaCertificate,
		shouldFail:         true,
		expectedError:      ":DECODE_ERROR:",
		expectedLocalError: "remote error: error decoding message",
	})

	testCases = append(testCases, testCase{
		name: "ClientAuth-NoFallback-ECDSA",
		config: Config{
			MaxVersion: VersionTLS12,
			ClientAuth: RequireAnyClientCert,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureECDSAWithSHA1,
			},
			Bugs: ProtocolBugs{
				NoSignatureAlgorithms: true,
			},
		},
		shimCertificate:    &ecdsaP256Certificate,
		shouldFail:         true,
		expectedError:      ":DECODE_ERROR:",
		expectedLocalError: "remote error: error decoding message",
	})

	testCases = append(testCases, testCase{
		name: "ClientAuth-NoFallback-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			ClientAuth: RequireAnyClientCert,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureRSAPKCS1WithSHA1,
			},
			Bugs: ProtocolBugs{
				NoSignatureAlgorithms: true,
			},
		},
		shimCertificate:    &rsaCertificate,
		shouldFail:         true,
		expectedError:      ":DECODE_ERROR:",
		expectedLocalError: "remote error: error decoding message",
	})

	// Test that signature preferences are enforced. BoringSSL does not
	// implement MD5 signatures.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ClientAuth-Enforced",
		config: Config{
			MaxVersion: VersionTLS12,
			Credential: rsaCertificate.WithSignatureAlgorithms(signatureRSAPKCS1WithMD5),
			Bugs: ProtocolBugs{
				IgnorePeerSignatureAlgorithmPreferences: true,
			},
		},
		flags:         []string{"-require-any-client-certificate"},
		shouldFail:    true,
		expectedError: ":WRONG_SIGNATURE_TYPE:",
	})

	testCases = append(testCases, testCase{
		name: "ServerAuth-Enforced",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			Credential:   rsaCertificate.WithSignatureAlgorithms(signatureRSAPKCS1WithMD5),
			Bugs: ProtocolBugs{
				IgnorePeerSignatureAlgorithmPreferences: true,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_SIGNATURE_TYPE:",
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ClientAuth-Enforced-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Credential: rsaCertificate.WithSignatureAlgorithms(signatureRSAPKCS1WithMD5),
			Bugs: ProtocolBugs{
				IgnorePeerSignatureAlgorithmPreferences: true,
				IgnoreSignatureVersionChecks:            true,
			},
		},
		flags:         []string{"-require-any-client-certificate"},
		shouldFail:    true,
		expectedError: ":WRONG_SIGNATURE_TYPE:",
	})

	testCases = append(testCases, testCase{
		name: "ServerAuth-Enforced-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Credential: rsaCertificate.WithSignatureAlgorithms(signatureRSAPKCS1WithMD5),
			Bugs: ProtocolBugs{
				IgnorePeerSignatureAlgorithmPreferences: true,
				IgnoreSignatureVersionChecks:            true,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_SIGNATURE_TYPE:",
	})

	// Test that the negotiated signature algorithm respects the client and
	// server preferences.
	testCases = append(testCases, testCase{
		name: "NoCommonAlgorithms",
		config: Config{
			MaxVersion: VersionTLS12,
			ClientAuth: RequireAnyClientCert,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureRSAPKCS1WithSHA512,
				signatureRSAPKCS1WithSHA1,
			},
		},
		shimCertificate: rsaCertificate.WithSignatureAlgorithms(signatureRSAPKCS1WithSHA256),
		shouldFail:      true,
		expectedError:   ":NO_COMMON_SIGNATURE_ALGORITHMS:",
	})
	testCases = append(testCases, testCase{
		name: "NoCommonAlgorithms-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			ClientAuth: RequireAnyClientCert,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureRSAPSSWithSHA512,
				signatureRSAPSSWithSHA384,
			},
		},
		shimCertificate: rsaCertificate.WithSignatureAlgorithms(signatureRSAPSSWithSHA256),
		shouldFail:      true,
		expectedError:   ":NO_COMMON_SIGNATURE_ALGORITHMS:",
	})
	testCases = append(testCases, testCase{
		name: "Agree-Digest-SHA256",
		config: Config{
			MaxVersion: VersionTLS12,
			ClientAuth: RequireAnyClientCert,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureRSAPKCS1WithSHA1,
				signatureRSAPKCS1WithSHA256,
			},
		},
		shimCertificate: rsaCertificate.WithSignatureAlgorithms(
			signatureRSAPKCS1WithSHA256,
			signatureRSAPKCS1WithSHA1,
		),
		expectations: connectionExpectations{
			peerSignatureAlgorithm: signatureRSAPKCS1WithSHA256,
		},
	})
	testCases = append(testCases, testCase{
		name: "Agree-Digest-SHA1",
		config: Config{
			MaxVersion: VersionTLS12,
			ClientAuth: RequireAnyClientCert,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureRSAPKCS1WithSHA1,
			},
		},
		shimCertificate: rsaCertificate.WithSignatureAlgorithms(
			signatureRSAPKCS1WithSHA512,
			signatureRSAPKCS1WithSHA256,
			signatureRSAPKCS1WithSHA1,
		),
		expectations: connectionExpectations{
			peerSignatureAlgorithm: signatureRSAPKCS1WithSHA1,
		},
	})
	testCases = append(testCases, testCase{
		name: "Agree-Digest-Default",
		config: Config{
			MaxVersion: VersionTLS12,
			ClientAuth: RequireAnyClientCert,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureRSAPKCS1WithSHA256,
				signatureECDSAWithP256AndSHA256,
				signatureRSAPKCS1WithSHA1,
				signatureECDSAWithSHA1,
			},
		},
		shimCertificate: &rsaCertificate,
		expectations: connectionExpectations{
			peerSignatureAlgorithm: signatureRSAPKCS1WithSHA256,
		},
	})

	// Test that the signing preference list may include extra algorithms
	// without negotiation problems.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "FilterExtraAlgorithms",
		config: Config{
			MaxVersion: VersionTLS12,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureRSAPKCS1WithSHA256,
			},
		},
		shimCertificate: rsaCertificate.WithSignatureAlgorithms(
			signatureECDSAWithP256AndSHA256,
			signatureRSAPKCS1WithSHA256,
		),
		expectations: connectionExpectations{
			peerSignatureAlgorithm: signatureRSAPKCS1WithSHA256,
		},
	})

	// In TLS 1.2 and below, ECDSA uses the curve list rather than the
	// signature algorithms.
	testCases = append(testCases, testCase{
		name: "CheckLeafCurve",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256},
			Credential:   &ecdsaP256Certificate,
		},
		flags:         []string{"-curves", strconv.Itoa(int(CurveP384))},
		shouldFail:    true,
		expectedError: ":BAD_ECC_CERT:",
	})

	// In TLS 1.3, ECDSA does not use the ECDHE curve list.
	testCases = append(testCases, testCase{
		name: "CheckLeafCurve-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Credential: &ecdsaP256Certificate,
		},
		flags: []string{"-curves", strconv.Itoa(int(CurveP384))},
	})

	// In TLS 1.2, the ECDSA curve is not in the signature algorithm, so the
	// shim should accept P-256 with SHA-384.
	testCases = append(testCases, testCase{
		name: "ECDSACurveMismatch-Verify-TLS12",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256},
			Credential:   ecdsaP256Certificate.WithSignatureAlgorithms(signatureECDSAWithP384AndSHA384),
		},
	})

	// In TLS 1.3, the ECDSA curve comes from the signature algorithm, so the
	// shim should reject P-256 with SHA-384.
	testCases = append(testCases, testCase{
		name: "ECDSACurveMismatch-Verify-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Credential: ecdsaP256Certificate.WithSignatureAlgorithms(signatureECDSAWithP384AndSHA384),
			Bugs: ProtocolBugs{
				SkipECDSACurveCheck: true,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_SIGNATURE_TYPE:",
	})

	// Signature algorithm selection in TLS 1.3 should take the curve into
	// account.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ECDSACurveMismatch-Sign-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureECDSAWithP384AndSHA384,
				signatureECDSAWithP256AndSHA256,
			},
		},
		shimCertificate: &ecdsaP256Certificate,
		expectations: connectionExpectations{
			peerSignatureAlgorithm: signatureECDSAWithP256AndSHA256,
		},
	})

	// RSASSA-PSS with SHA-512 is too large for 1024-bit RSA. Test that the
	// server does not attempt to sign in that case.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "RSA-PSS-Large",
		config: Config{
			MaxVersion: VersionTLS13,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureRSAPSSWithSHA512,
			},
		},
		shimCertificate: &rsa1024Certificate,
		shouldFail:      true,
		expectedError:   ":NO_COMMON_SIGNATURE_ALGORITHMS:",
	})

	// Test that RSA-PSS is enabled by default for TLS 1.2.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "RSA-PSS-Default-Verify",
		config: Config{
			MaxVersion: VersionTLS12,
			Credential: rsaCertificate.WithSignatureAlgorithms(signatureRSAPSSWithSHA256),
		},
		flags: []string{"-max-version", strconv.Itoa(VersionTLS12)},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "RSA-PSS-Default-Sign",
		config: Config{
			MaxVersion: VersionTLS12,
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureRSAPSSWithSHA256,
			},
		},
		flags: []string{"-max-version", strconv.Itoa(VersionTLS12)},
	})

	// TLS 1.1 and below has no way to advertise support for or negotiate
	// Ed25519's signature algorithm.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "NoEd25519-TLS11-ServerAuth-Verify",
		config: Config{
			MaxVersion: VersionTLS11,
			Credential: &ed25519Certificate,
			Bugs: ProtocolBugs{
				// Sign with Ed25519 even though it is TLS 1.1.
				SigningAlgorithmForLegacyVersions: signatureEd25519,
			},
		},
		flags:         []string{"-verify-prefs", strconv.Itoa(int(signatureEd25519))},
		shouldFail:    true,
		expectedError: ":PEER_ERROR_UNSUPPORTED_CERTIFICATE_TYPE:",
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "NoEd25519-TLS11-ServerAuth-Sign",
		config: Config{
			MaxVersion: VersionTLS11,
		},
		shimCertificate: &ed25519Certificate,
		shouldFail:      true,
		expectedError:   ":NO_SHARED_CIPHER:",
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "NoEd25519-TLS11-ClientAuth-Verify",
		config: Config{
			MaxVersion: VersionTLS11,
			Credential: &ed25519Certificate,
			Bugs: ProtocolBugs{
				// Sign with Ed25519 even though it is TLS 1.1.
				SigningAlgorithmForLegacyVersions: signatureEd25519,
			},
		},
		flags: []string{
			"-verify-prefs", strconv.Itoa(int(signatureEd25519)),
			"-require-any-client-certificate",
		},
		shouldFail:    true,
		expectedError: ":PEER_ERROR_UNSUPPORTED_CERTIFICATE_TYPE:",
	})
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "NoEd25519-TLS11-ClientAuth-Sign",
		config: Config{
			MaxVersion: VersionTLS11,
			ClientAuth: RequireAnyClientCert,
		},
		shimCertificate: &ed25519Certificate,
		shouldFail:      true,
		expectedError:   ":NO_COMMON_SIGNATURE_ALGORITHMS:",
	})

	// Test Ed25519 is not advertised by default.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "Ed25519DefaultDisable-NoAdvertise",
		config: Config{
			Credential: &ed25519Certificate,
		},
		shouldFail:         true,
		expectedLocalError: "tls: no common signature algorithms",
	})

	// Test Ed25519, when disabled, is not accepted if the peer ignores our
	// preferences.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "Ed25519DefaultDisable-NoAccept",
		config: Config{
			Credential: &ed25519Certificate,
			Bugs: ProtocolBugs{
				IgnorePeerSignatureAlgorithmPreferences: true,
			},
		},
		shouldFail:         true,
		expectedLocalError: "remote error: illegal parameter",
		expectedError:      ":WRONG_SIGNATURE_TYPE:",
	})

	// Test that configuring verify preferences changes what the client
	// advertises.
	testCases = append(testCases, testCase{
		name: "VerifyPreferences-Advertised",
		config: Config{
			Credential: rsaCertificate.WithSignatureAlgorithms(
				signatureRSAPSSWithSHA256,
				signatureRSAPSSWithSHA384,
				signatureRSAPSSWithSHA512,
			),
		},
		flags: []string{
			"-verify-prefs", strconv.Itoa(int(signatureRSAPSSWithSHA384)),
			"-expect-peer-signature-algorithm", strconv.Itoa(int(signatureRSAPSSWithSHA384)),
		},
	})

	// Test that the client advertises a set which the runner can find
	// nothing in common with.
	testCases = append(testCases, testCase{
		name: "VerifyPreferences-NoCommonAlgorithms",
		config: Config{
			Credential: rsaCertificate.WithSignatureAlgorithms(
				signatureRSAPSSWithSHA256,
				signatureRSAPSSWithSHA512,
			),
		},
		flags: []string{
			"-verify-prefs", strconv.Itoa(int(signatureRSAPSSWithSHA384)),
		},
		shouldFail:         true,
		expectedLocalError: "tls: no common signature algorithms",
	})

	// Test that the client enforces its preferences when configured.
	testCases = append(testCases, testCase{
		name: "VerifyPreferences-Enforced",
		config: Config{
			Credential: rsaCertificate.WithSignatureAlgorithms(
				signatureRSAPSSWithSHA256,
				signatureRSAPSSWithSHA512,
			),
			Bugs: ProtocolBugs{
				IgnorePeerSignatureAlgorithmPreferences: true,
			},
		},
		flags: []string{
			"-verify-prefs", strconv.Itoa(int(signatureRSAPSSWithSHA384)),
		},
		shouldFail:         true,
		expectedLocalError: "remote error: illegal parameter",
		expectedError:      ":WRONG_SIGNATURE_TYPE:",
	})

	// Test that explicitly configuring Ed25519 is as good as changing the
	// boolean toggle.
	testCases = append(testCases, testCase{
		name: "VerifyPreferences-Ed25519",
		config: Config{
			Credential: &ed25519Certificate,
		},
		flags: []string{
			"-verify-prefs", strconv.Itoa(int(signatureEd25519)),
		},
	})

	for _, testType := range []testType{clientTest, serverTest} {
		for _, ver := range tlsVersions {
			if ver.version < VersionTLS12 {
				continue
			}

			prefix := "Client-" + ver.name + "-"
			noCommonAlgorithmsError := ":NO_COMMON_SIGNATURE_ALGORITHMS:"
			if testType == serverTest {
				prefix = "Server-" + ver.name + "-"
				// In TLS 1.2 servers, cipher selection and algorithm
				// selection are linked.
				if ver.version <= VersionTLS12 {
					noCommonAlgorithmsError = ":NO_SHARED_CIPHER:"
				}
			}

			// Test that the shim will not sign MD5/SHA1 with RSA at TLS 1.2,
			// even if specified in signing preferences.
			testCases = append(testCases, testCase{
				testType: testType,
				name:     prefix + "NoSign-RSA_PKCS1_MD5_SHA1",
				config: Config{
					MaxVersion:                ver.version,
					CipherSuites:              signingCiphers,
					ClientAuth:                RequireAnyClientCert,
					VerifySignatureAlgorithms: []signatureAlgorithm{signatureRSAPKCS1WithMD5AndSHA1},
				},
				shimCertificate: rsaCertificate.WithSignatureAlgorithms(
					signatureRSAPKCS1WithMD5AndSHA1,
					// Include a valid algorithm as well, to avoid an empty list
					// if filtered out.
					signatureRSAPKCS1WithSHA256,
				),
				shouldFail:    true,
				expectedError: noCommonAlgorithmsError,
			})

			// Test that the shim will not accept MD5/SHA1 with RSA at TLS 1.2,
			// even if specified in verify preferences.
			testCases = append(testCases, testCase{
				testType: testType,
				name:     prefix + "NoVerify-RSA_PKCS1_MD5_SHA1",
				config: Config{
					MaxVersion: ver.version,
					Credential: &rsaCertificate,
					Bugs: ProtocolBugs{
						IgnorePeerSignatureAlgorithmPreferences: true,
						AlwaysSignAsLegacyVersion:               true,
						SendSignatureAlgorithm:                  signatureRSAPKCS1WithMD5AndSHA1,
					},
				},
				shimCertificate: &rsaCertificate,
				flags: []string{
					"-verify-prefs", strconv.Itoa(int(signatureRSAPKCS1WithMD5AndSHA1)),
					// Include a valid algorithm as well, to avoid an empty list
					// if filtered out.
					"-verify-prefs", strconv.Itoa(int(signatureRSAPKCS1WithSHA256)),
					"-require-any-client-certificate",
				},
				shouldFail:    true,
				expectedError: ":WRONG_SIGNATURE_TYPE:",
			})
		}
	}

	// Test that, when there are no signature algorithms in common in TLS
	// 1.2, the server will still consider the legacy RSA key exchange.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "NoCommonSignatureAlgorithms-TLS12-Fallback",
		config: Config{
			MaxVersion: VersionTLS12,
			CipherSuites: []uint16{
				TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
				TLS_RSA_WITH_AES_128_GCM_SHA256,
			},
			VerifySignatureAlgorithms: []signatureAlgorithm{
				signatureECDSAWithP256AndSHA256,
			},
		},
		expectations: connectionExpectations{
			cipher: TLS_RSA_WITH_AES_128_GCM_SHA256,
		},
	})
}

// timeouts is the default retransmit schedule for BoringSSL. It doubles and
// caps at 60 seconds. On the 13th timeout, it gives up.
var timeouts = []time.Duration{
	400 * time.Millisecond,
	800 * time.Millisecond,
	1600 * time.Millisecond,
	3200 * time.Millisecond,
	6400 * time.Millisecond,
	12800 * time.Millisecond,
	25600 * time.Millisecond,
	51200 * time.Millisecond,
	60 * time.Second,
	60 * time.Second,
	60 * time.Second,
	60 * time.Second,
	60 * time.Second,
}

// shortTimeouts is an alternate set of timeouts which would occur if the
// initial timeout duration was set to 250ms.
var shortTimeouts = []time.Duration{
	250 * time.Millisecond,
	500 * time.Millisecond,
	1 * time.Second,
	2 * time.Second,
	4 * time.Second,
	8 * time.Second,
	16 * time.Second,
	32 * time.Second,
	60 * time.Second,
	60 * time.Second,
	60 * time.Second,
	60 * time.Second,
	60 * time.Second,
}

// dtlsPrevEpochExpiration is how long before the shim releases old epochs. Add
// an extra second to allow the shim to be less precise.
const dtlsPrevEpochExpiration = 4*time.Minute + 1*time.Second

func addDTLSRetransmitTests() {
	for _, shortTimeout := range []bool{false, true} {
		for _, vers := range allVersions(dtls) {
			suffix := "-" + vers.name
			flags := []string{"-async"} // Retransmit tests require async.
			useTimeouts := timeouts
			if shortTimeout {
				suffix += "-Short"
				flags = append(flags, "-initial-timeout-duration-ms", "250")
				useTimeouts = shortTimeouts
			}

			// Testing NewSessionTicket is tricky. First, BoringSSL sends two
			// tickets in a row. These are conceptually separate flights, but we
			// test them as one flight. Second, these tickets are sent
			// concurrently with the runner's first test message. The shim's
			// reply will come in before any retransmit challenges.
			// handleNewSessionTicket corrects for both effects.
			handleNewSessionTicket := func(f ACKFlightFunc) ACKFlightFunc {
				if vers.version < VersionTLS13 {
					return f
				}
				return func(c *DTLSController, prev, received []DTLSMessage, records []DTLSRecordNumberInfo) {
					// BoringSSL sends two NewSessionTickets in a row.
					if received[0].Type == typeNewSessionTicket && len(received) < 2 {
						c.MergeIntoNextFlight()
						return
					}
					// NewSessionTicket is sent in parallel with the runner's
					// first application data. Consume the shim's reply.
					testMessage := makeTestMessage(0, 32)
					if received[0].Type == typeNewSessionTicket {
						c.ReadAppData(c.InEpoch(), expectedReply(testMessage))
					}
					// Run the test, without any stray messages in the way.
					f(c, prev, received, records)
					// The test loop is expecting a reply to the first message.
					// Prime the shim to send it again.
					if received[0].Type == typeNewSessionTicket {
						c.WriteAppData(c.OutEpoch(), testMessage)
					}
				}
			}

			// In all versions, the sender will retransmit the whole flight if
			// it times out and hears nothing.
			writeFlightBasic := func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
				if len(received) > 0 {
					// Exercise every timeout but the last one (which would fail the
					// connection).
					for _, t := range useTimeouts[:len(useTimeouts)-1] {
						c.ExpectNextTimeout(t)
						c.AdvanceClock(t)
						c.ReadRetransmit()
					}
					c.ExpectNextTimeout(useTimeouts[len(useTimeouts)-1])
				}
				// Finally release the whole flight to the shim.
				c.WriteFlight(next)
			}
			ackFlightBasic := handleNewSessionTicket(func(c *DTLSController, prev, received []DTLSMessage, records []DTLSRecordNumberInfo) {
				if vers.version >= VersionTLS13 {
					// In DTLS 1.3, final flights (either handshake or post-handshake)
					// are retransmited until ACKed. Exercise every timeout but
					// the last one (which would fail the connection).
					for _, t := range useTimeouts[:len(useTimeouts)-1] {
						c.ExpectNextTimeout(t)
						c.AdvanceClock(t)
						c.ReadRetransmit()
					}
					c.ExpectNextTimeout(useTimeouts[len(useTimeouts)-1])
					// Finally ACK the flight.
					c.WriteACK(c.OutEpoch(), records)
					return
				}
				// In DTLS 1.2, the final flight is retransmitted on receipt of
				// the previous flight. Test the peer is willing to retransmit
				// it several times.
				for i := 0; i < 5; i++ {
					c.WriteFlight(prev)
					c.ReadRetransmit()
				}
			})
			testCases = append(testCases, testCase{
				protocol: dtls,
				name:     "DTLS-Retransmit-Client-Basic" + suffix,
				config: Config{
					MaxVersion: vers.version,
					Bugs: ProtocolBugs{
						WriteFlightDTLS: writeFlightBasic,
						ACKFlightDTLS:   ackFlightBasic,
					},
				},
				resumeSession: true,
				flags:         flags,
			})
			testCases = append(testCases, testCase{
				protocol: dtls,
				testType: serverTest,
				name:     "DTLS-Retransmit-Server-Basic" + suffix,
				config: Config{
					MaxVersion: vers.version,
					Bugs: ProtocolBugs{
						WriteFlightDTLS: writeFlightBasic,
						ACKFlightDTLS:   ackFlightBasic,
					},
				},
				resumeSession: true,
				flags:         flags,
			})

			if vers.version <= VersionTLS12 {
				// In DTLS 1.2, receiving a part of the next flight should not stop
				// the retransmission timer.
				testCases = append(testCases, testCase{
					protocol: dtls,
					name:     "DTLS-Retransmit-PartialProgress" + suffix,
					config: Config{
						MaxVersion: vers.version,
						Bugs: ProtocolBugs{
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								// Send a portion of the first message. The rest was lost.
								msg := next[0]
								split := len(msg.Data) / 2
								c.WriteFragments([]DTLSFragment{msg.Fragment(0, split)})
								// If we time out, the shim should still retransmit. It knows
								// we received the whole flight, but the shim should use a
								// retransmit to request the runner try again.
								c.AdvanceClock(useTimeouts[0])
								c.ReadRetransmit()
								// "Retransmit" the rest of the flight. The shim should remember
								// the portion that was already sent.
								rest := []DTLSFragment{msg.Fragment(split, len(msg.Data)-split)}
								for _, m := range next[1:] {
									rest = append(rest, m.Fragment(0, len(m.Data)))
								}
								c.WriteFragments(rest)
							},
						},
					},
					flags: flags,
				})
			} else {
				// In DTLS 1.3, receiving a part of the next flight implicitly ACKs
				// the previous flight.
				testCases = append(testCases, testCase{
					testType: serverTest,
					protocol: dtls,
					name:     "DTLS-Retransmit-PartialProgress-Server" + suffix,
					config: Config{
						MaxVersion:    vers.version,
						DefaultCurves: []CurveID{}, // Force HelloRetryRequest.
						Bugs: ProtocolBugs{
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if len(received) == 0 && next[0].Type == typeClientHello {
									// Send the initial ClientHello as-is.
									c.WriteFlight(next)
									return
								}

								// Send a portion of the first message. The rest was lost.
								msg := next[0]
								split := len(msg.Data) / 2
								c.WriteFragments([]DTLSFragment{msg.Fragment(0, split)})
								// After waiting the current timeout, the shim should ACK
								// the partial flight.
								c.ExpectNextTimeout(useTimeouts[0] / 4)
								c.AdvanceClock(useTimeouts[0] / 4)
								c.ReadACK(c.InEpoch())
								// The partial flight is enough to ACK the previous flight.
								// The shim should stop retransmitting and even stop the
								// retransmit timer.
								c.ExpectNoNextTimeout()
								for _, t := range useTimeouts {
									c.AdvanceClock(t)
								}
								// "Retransmit" the rest of the flight. The shim should remember
								// the portion that was already sent.
								rest := []DTLSFragment{msg.Fragment(split, len(msg.Data)-split)}
								for _, m := range next[1:] {
									rest = append(rest, m.Fragment(0, len(m.Data)))
								}
								c.WriteFragments(rest)
							},
						},
					},
					flags: flags,
				})

				// When the shim is a client, receiving fragments before the version is
				// known does not trigger this behavior.
				testCases = append(testCases, testCase{
					protocol: dtls,
					name:     "DTLS-Retransmit-PartialProgress-Client" + suffix,
					config: Config{
						MaxVersion: vers.version,
						Bugs: ProtocolBugs{
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								msg := next[0]
								if msg.Type != typeServerHello {
									// Post-handshake is tested separately.
									c.WriteFlight(next)
									return
								}
								// Send a portion of the ServerHello. The rest was lost.
								split := len(msg.Data) / 2
								c.WriteFragments([]DTLSFragment{msg.Fragment(0, split)})

								// The shim did not know this was DTLS 1.3, so it still
								// retransmits ClientHello.
								c.ExpectNextTimeout(useTimeouts[0])
								c.AdvanceClock(useTimeouts[0])
								c.ReadRetransmit()

								// Finish the ServerHello. The version is still not known,
								// at the time the ServerHello fragment is processed, This
								// is not as efficient as we could be; we could go back and
								// implicitly ACK once the version is known. But the last
								// byte of ServerHello will almost certainly be in the same
								// packet as EncryptedExtensions, which will trigger the case
								// below.
								c.WriteFragments([]DTLSFragment{msg.Fragment(split, len(msg.Data)-split)})
								c.ExpectNextTimeout(useTimeouts[1])
								c.AdvanceClock(useTimeouts[1])
								c.ReadRetransmit()

								// Send EncryptedExtensions. The shim now knows the version.
								c.WriteFragments([]DTLSFragment{next[1].Fragment(0, len(next[1].Data))})

								// The shim should ACK the partial flight. The shim hasn't
								// gotten to epoch 3 yet, so the ACK will come in epoch 2.
								c.AdvanceClock(useTimeouts[2] / 4)
								c.ReadACK(uint16(encryptionHandshake))

								// This is enough to ACK the previous flight. The shim
								// should stop retransmitting and even stop the timer.
								c.ExpectNoNextTimeout()
								for _, t := range useTimeouts[2:] {
									c.AdvanceClock(t)
								}

								// "Retransmit" the rest of the flight. The shim should remember
								// the portion that was already sent.
								var rest []DTLSFragment
								for _, m := range next[2:] {
									rest = append(rest, m.Fragment(0, len(m.Data)))
								}
								c.WriteFragments(rest)
							},
						},
					},
					flags: flags,
				})
			}

			// Test that exceeding the timeout schedule hits a read
			// timeout.
			testCases = append(testCases, testCase{
				protocol: dtls,
				name:     "DTLS-Retransmit-Timeout" + suffix,
				config: Config{
					MaxVersion: vers.version,
					Bugs: ProtocolBugs{
						WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
							for _, t := range useTimeouts[:len(useTimeouts)-1] {
								c.ExpectNextTimeout(t)
								c.AdvanceClock(t)
								c.ReadRetransmit()
							}
							c.ExpectNextTimeout(useTimeouts[len(useTimeouts)-1])
							c.AdvanceClock(useTimeouts[len(useTimeouts)-1])
							// The shim should give up at this point.
						},
					},
				},
				resumeSession: true,
				flags:         flags,
				shouldFail:    true,
				expectedError: ":READ_TIMEOUT_EXPIRED:",
			})

			// Test that timeout handling has a fudge factor, due to API
			// problems.
			testCases = append(testCases, testCase{
				protocol: dtls,
				name:     "DTLS-Retransmit-Fudge" + suffix,
				config: Config{
					MaxVersion: vers.version,
					Bugs: ProtocolBugs{
						WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
							if len(received) > 0 {
								c.ExpectNextTimeout(useTimeouts[0])
								c.AdvanceClock(useTimeouts[0] - 10*time.Millisecond)
								c.ReadRetransmit()
							}
							c.WriteFlight(next)
						},
					},
				},
				resumeSession: true,
				flags:         flags,
			})

			// Test that the shim can retransmit at different MTUs.
			testCases = append(testCases, testCase{
				protocol: dtls,
				name:     "DTLS-Retransmit-ChangeMTU" + suffix,
				config: Config{
					MaxVersion: vers.version,
					// Request a client certificate, so the shim has more to send.
					ClientAuth: RequireAnyClientCert,
					Bugs: ProtocolBugs{
						WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
							for i, mtu := range []int{300, 301, 302, 303, 299, 298, 297} {
								c.SetMTU(mtu)
								c.AdvanceClock(useTimeouts[i])
								c.ReadRetransmit()
							}
							c.WriteFlight(next)
						},
					},
				},
				shimCertificate: &rsaChainCertificate,
				flags:           flags,
			})

			// DTLS 1.3 uses explicit ACKs.
			if vers.version >= VersionTLS13 {
				// The two server flights (HelloRetryRequest and ServerHello..Finished)
				// happen after the shim has learned the version, so they are more
				// straightforward. In these tests, we trigger HelloRetryRequest,
				// and also use ML-KEM with rsaChainCertificate and a limited MTU,
				// to increase the number of records and exercise more complex
				// ACK patterns.

				// After ACKing everything, the shim should stop retransmitting.
				testCases = append(testCases, testCase{
					protocol: dtls,
					testType: serverTest,
					name:     "DTLS-Retransmit-Server-ACKEverything" + suffix,
					config: Config{
						MaxVersion:       vers.version,
						Credential:       &rsaChainCertificate,
						CurvePreferences: []CurveID{CurveX25519MLKEM768},
						DefaultCurves:    []CurveID{}, // Force HelloRetryRequest.
						Bugs: ProtocolBugs{
							// Send smaller packets to exercise more ACK cases.
							MaxPacketLength:          512,
							MaxHandshakeRecordLength: 512,
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if len(received) > 0 {
									ackEpoch := received[len(received)-1].Epoch
									c.ExpectNextTimeout(useTimeouts[0])
									c.WriteACK(ackEpoch, records)
									// After everything is ACKed, the shim should stop the timer
									// and wait for the next flight.
									c.ExpectNoNextTimeout()
									for _, t := range useTimeouts {
										c.AdvanceClock(t)
									}
								}
								c.WriteFlight(next)
							},
							ACKFlightDTLS: handleNewSessionTicket(func(c *DTLSController, prev, received []DTLSMessage, records []DTLSRecordNumberInfo) {
								ackEpoch := received[len(received)-1].Epoch
								c.ExpectNextTimeout(useTimeouts[0])
								c.WriteACK(ackEpoch, records)
								// After everything is ACKed, the shim should stop the timer.
								c.ExpectNoNextTimeout()
								for _, t := range useTimeouts {
									c.AdvanceClock(t)
								}
							}),
							SequenceNumberMapping: func(in uint64) uint64 {
								// Perturb sequence numbers to test that ACKs are sorted.
								return in ^ 63
							},
						},
					},
					shimCertificate: &rsaChainCertificate,
					flags: slices.Concat(flags, []string{
						"-mtu", "512",
						"-curves", strconv.Itoa(int(CurveX25519MLKEM768)),
						// Request a client certificate so the client final flight is
						// larger.
						"-require-any-client-certificate",
					}),
				})

				// ACK packets one by one, in reverse.
				testCases = append(testCases, testCase{
					protocol: dtls,
					testType: serverTest,
					name:     "DTLS-Retransmit-Server-ACKReverse" + suffix,
					config: Config{
						MaxVersion:       vers.version,
						CurvePreferences: []CurveID{CurveX25519MLKEM768},
						DefaultCurves:    []CurveID{}, // Force HelloRetryRequest.
						Bugs: ProtocolBugs{
							MaxPacketLength: 512,
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if len(received) > 0 {
									ackEpoch := received[len(received)-1].Epoch
									for _, t := range useTimeouts[:len(useTimeouts)-1] {
										if len(records) > 0 {
											c.WriteACK(ackEpoch, []DTLSRecordNumberInfo{records[len(records)-1]})
										}
										c.AdvanceClock(t)
										records = c.ReadRetransmit()
									}
								}
								c.WriteFlight(next)
							},
							ACKFlightDTLS: handleNewSessionTicket(func(c *DTLSController, prev, received []DTLSMessage, records []DTLSRecordNumberInfo) {
								ackEpoch := received[len(received)-1].Epoch
								for _, t := range useTimeouts[:len(useTimeouts)-1] {
									if len(records) > 0 {
										c.WriteACK(ackEpoch, []DTLSRecordNumberInfo{records[len(records)-1]})
									}
									c.AdvanceClock(t)
									records = c.ReadRetransmit()
								}
							}),
						},
					},
					shimCertificate: &rsaChainCertificate,
					flags:           slices.Concat(flags, []string{"-mtu", "512", "-curves", strconv.Itoa(int(CurveX25519MLKEM768))}),
				})

				// ACK packets one by one, forwards.
				testCases = append(testCases, testCase{
					protocol: dtls,
					testType: serverTest,
					name:     "DTLS-Retransmit-Server-ACKForwards" + suffix,
					config: Config{
						MaxVersion:       vers.version,
						CurvePreferences: []CurveID{CurveX25519MLKEM768},
						DefaultCurves:    []CurveID{}, // Force HelloRetryRequest.
						Bugs: ProtocolBugs{
							MaxPacketLength: 512,
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if len(received) > 0 {
									ackEpoch := received[len(received)-1].Epoch
									for _, t := range useTimeouts[:len(useTimeouts)-1] {
										if len(records) > 0 {
											c.WriteACK(ackEpoch, []DTLSRecordNumberInfo{records[0]})
										}
										c.AdvanceClock(t)
										records = c.ReadRetransmit()
									}
								}
								c.WriteFlight(next)
							},
							ACKFlightDTLS: handleNewSessionTicket(func(c *DTLSController, prev, received []DTLSMessage, records []DTLSRecordNumberInfo) {
								ackEpoch := received[len(received)-1].Epoch
								for _, t := range useTimeouts[:len(useTimeouts)-1] {
									if len(records) > 0 {
										c.WriteACK(ackEpoch, []DTLSRecordNumberInfo{records[0]})
									}
									c.AdvanceClock(t)
									records = c.ReadRetransmit()
								}
							}),
						},
					},
					shimCertificate: &rsaChainCertificate,
					flags:           slices.Concat(flags, []string{"-mtu", "512", "-curves", strconv.Itoa(int(CurveX25519MLKEM768))}),
				})

				// ACK 1/3 the packets each time.
				testCases = append(testCases, testCase{
					protocol: dtls,
					testType: serverTest,
					name:     "DTLS-Retransmit-Server-ACKIterate" + suffix,
					config: Config{
						MaxVersion:       vers.version,
						CurvePreferences: []CurveID{CurveX25519MLKEM768},
						DefaultCurves:    []CurveID{}, // Force HelloRetryRequest.
						Bugs: ProtocolBugs{
							MaxPacketLength: 512,
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if len(received) > 0 {
									ackEpoch := received[len(received)-1].Epoch
									for i, t := range useTimeouts[:len(useTimeouts)-1] {
										if len(records) > 0 {
											ack := make([]DTLSRecordNumberInfo, 0, (len(records)+2)/3)
											for i := 0; i < len(records); i += 3 {
												ack = append(ack, records[i])
											}
											c.WriteACK(ackEpoch, ack)
										}
										// Change the MTU every iteration, to make the fragment
										// patterns more complex.
										c.SetMTU(512 + i)
										c.AdvanceClock(t)
										records = c.ReadRetransmit()
									}
								}
								c.WriteFlight(next)
							},
							ACKFlightDTLS: handleNewSessionTicket(func(c *DTLSController, prev, received []DTLSMessage, records []DTLSRecordNumberInfo) {
								ackEpoch := received[len(received)-1].Epoch
								for _, t := range useTimeouts[:len(useTimeouts)-1] {
									if len(records) > 0 {
										c.WriteACK(ackEpoch, []DTLSRecordNumberInfo{records[0]})
									}
									c.AdvanceClock(t)
									records = c.ReadRetransmit()
								}
							}),
						},
					},
					shimCertificate: &rsaChainCertificate,
					flags:           slices.Concat(flags, []string{"-mtu", "512", "-curves", strconv.Itoa(int(CurveX25519MLKEM768))}),
				})

				// ACKing packets that have already been ACKed is a no-op.
				testCases = append(testCases, testCase{
					protocol: dtls,
					testType: serverTest,
					name:     "DTLS-Retransmit-Server-ACKDuplicate" + suffix,
					config: Config{
						MaxVersion: vers.version,
						Bugs: ProtocolBugs{
							SendHelloRetryRequestCookie: []byte("cookie"),
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if len(received) > 0 {
									ackEpoch := received[len(received)-1].Epoch
									// Keep ACKing the same record over and over.
									c.WriteACK(ackEpoch, records[:1])
									c.AdvanceClock(useTimeouts[0])
									c.ReadRetransmit()
									c.WriteACK(ackEpoch, records[:1])
									c.AdvanceClock(useTimeouts[1])
									c.ReadRetransmit()
								}
								c.WriteFlight(next)
							},
							ACKFlightDTLS: handleNewSessionTicket(func(c *DTLSController, prev, received []DTLSMessage, records []DTLSRecordNumberInfo) {
								ackEpoch := received[len(received)-1].Epoch
								// Keep ACKing the same record over and over.
								c.WriteACK(ackEpoch, records[:1])
								c.AdvanceClock(useTimeouts[0])
								c.ReadRetransmit()
								c.WriteACK(ackEpoch, records[:1])
								c.AdvanceClock(useTimeouts[1])
								c.ReadRetransmit()
								// ACK everything to clear the timer.
								c.WriteACK(ackEpoch, records)
							}),
						},
					},
					flags: flags,
				})

				// When ACKing ServerHello..Finished, the ServerHello might be
				// ACKed at epoch 0 or epoch 2, depending on how far the client
				// received. Test that epoch 0 is allowed by ACKing each packet
				// at the record it was received.
				testCases = append(testCases, testCase{
					protocol: dtls,
					testType: serverTest,
					name:     "DTLS-Retransmit-Server-ACKMatchingEpoch" + suffix,
					config: Config{
						MaxVersion: vers.version,
						Bugs: ProtocolBugs{
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if len(received) > 0 {
									for _, t := range useTimeouts[:len(useTimeouts)-1] {
										if len(records) > 0 {
											c.WriteACK(uint16(records[0].Epoch), []DTLSRecordNumberInfo{records[0]})
										}
										c.AdvanceClock(t)
										records = c.ReadRetransmit()
									}
								}
								c.WriteFlight(next)
							},
						},
					},
					flags: flags,
				})

				// However, records in the handshake may not be ACKed at lower
				// epoch than they were received.
				testCases = append(testCases, testCase{
					protocol: dtls,
					testType: serverTest,
					name:     "DTLS-Retransmit-Server-ACKBadEpoch" + suffix,
					config: Config{
						MaxVersion: vers.version,
						Bugs: ProtocolBugs{
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if len(received) == 0 {
									// Send the ClientHello.
									c.WriteFlight(next)
								} else {
									// Try to ACK ServerHello..Finished at epoch 0. The shim should reject this.
									c.WriteACK(0, records)
								}
							},
						},
					},
					flags:         flags,
					shouldFail:    true,
					expectedError: ":DECODE_ERROR:",
				})

				// The bad epoch check should notice when the epoch number
				// would overflow 2^16.
				testCases = append(testCases, testCase{
					protocol: dtls,
					testType: serverTest,
					name:     "DTLS-Retransmit-Server-ACKEpochOverflow" + suffix,
					config: Config{
						MaxVersion: vers.version,
						Bugs: ProtocolBugs{
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if len(received) == 0 {
									// Send the ClientHello.
									c.WriteFlight(next)
								} else {
									r := records[0]
									r.Epoch += 1 << 63
									c.WriteACK(0, []DTLSRecordNumberInfo{r})
								}
							},
						},
					},
					flags:         flags,
					shouldFail:    true,
					expectedError: ":DECODE_ERROR:",
				})

				// ACK some records from the first transmission, trigger a
				// retransmit, but then ACK the rest of the first transmission.
				testCases = append(testCases, testCase{
					protocol: dtls,
					testType: serverTest,
					name:     "DTLS-Retransmit-Server-ACKOldRecords" + suffix,
					config: Config{
						MaxVersion:       vers.version,
						CurvePreferences: []CurveID{CurveX25519MLKEM768},
						Bugs: ProtocolBugs{
							MaxPacketLength: 512,
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if len(received) > 0 {
									ackEpoch := received[len(received)-1].Epoch
									c.WriteACK(ackEpoch, records[len(records)/2:])
									c.AdvanceClock(useTimeouts[0])
									c.ReadRetransmit()
									c.WriteACK(ackEpoch, records[:len(records)/2])
									// Everything should be ACKed now. The shim should not
									// retransmit anything.
									c.AdvanceClock(useTimeouts[1])
									c.AdvanceClock(useTimeouts[2])
									c.AdvanceClock(useTimeouts[3])
								}
								c.WriteFlight(next)
							},
						},
					},
					flags: slices.Concat(flags, []string{"-mtu", "512", "-curves", strconv.Itoa(int(CurveX25519MLKEM768))}),
				})

				// If the shim sends too many records, it will eventually forget them.
				testCases = append(testCases, testCase{
					protocol: dtls,
					testType: serverTest,
					name:     "DTLS-Retransmit-Server-ACKForgottenRecords" + suffix,
					config: Config{
						MaxVersion:       vers.version,
						CurvePreferences: []CurveID{CurveX25519MLKEM768},
						Bugs: ProtocolBugs{
							MaxPacketLength: 256,
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if len(received) > 0 {
									// Make the peer retransmit many times, with a small MTU.
									for _, t := range useTimeouts[:len(useTimeouts)-2] {
										c.AdvanceClock(t)
										c.ReadRetransmit()
									}
									// ACK the first record the shim ever sent. It will have
									// fallen off the queue by now, so it is expected to not
									// impact the shim's retransmissions.
									c.WriteACK(c.OutEpoch(), []DTLSRecordNumberInfo{{DTLSRecordNumber: records[0].DTLSRecordNumber}})
									c.AdvanceClock(useTimeouts[len(useTimeouts)-2])
									c.ReadRetransmit()
								}
								c.WriteFlight(next)
							},
						},
					},
					flags: slices.Concat(flags, []string{"-mtu", "256", "-curves", strconv.Itoa(int(CurveX25519MLKEM768))}),
				})

				// The shim should ignore ACKs for a previous flight, and not get its
				// internal state confused.
				testCases = append(testCases, testCase{
					protocol: dtls,
					testType: serverTest,
					name:     "DTLS-Retransmit-Server-ACKPreviousFlight" + suffix,
					config: Config{
						MaxVersion:    vers.version,
						DefaultCurves: []CurveID{}, // Force a HelloRetryRequest.
						Bugs: ProtocolBugs{
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if next[len(next)-1].Type == typeFinished {
									// We are now sending client Finished, in response
									// to the shim's ServerHello. ACK the shim's first
									// record, which would have been part of
									// HelloRetryRequest. This should not impact retransmit.
									c.WriteACK(c.OutEpoch(), []DTLSRecordNumberInfo{{DTLSRecordNumber: DTLSRecordNumber{Epoch: 0, Sequence: 0}}})
									c.AdvanceClock(useTimeouts[0])
									c.ReadRetransmit()
								}
								c.WriteFlight(next)
							},
						},
					},
					flags: flags,
				})

				// Records that contain a mix of discarded and processed fragments should
				// not be ACKed.
				testCases = append(testCases, testCase{
					protocol: dtls,
					testType: serverTest,
					name:     "DTLS-Retransmit-Server-DoNotACKDiscardedFragments" + suffix,
					config: Config{
						MaxVersion:    vers.version,
						DefaultCurves: []CurveID{}, // Force a HelloRetryRequest.
						Bugs: ProtocolBugs{
							PackHandshakeFragments: 4096,
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								// Send the flight, but combine every fragment with a far future
								// fragment, which the shim will discard. During the handshake,
								// the shim has enough information to reject this entirely, but
								// that would require coordinating with the handshake state
								// machine. Instead, BoringSSL discards the fragment and skips
								// ACKing the packet.
								//
								// runner implicitly tests that the shim ACKs the Finished flight
								// (or, in case, that it is does not), so this exercises the final
								// ACK.
								for _, msg := range next {
									shouldDiscard := DTLSFragment{Epoch: msg.Epoch, Sequence: 1000, ShouldDiscard: true}
									c.WriteFragments([]DTLSFragment{shouldDiscard, msg.Fragment(0, len(msg.Data))})
									// The shim has nothing to ACK and thus no ACK timer (which
									// would be 1/4 of this value).
									c.ExpectNextTimeout(useTimeouts[0])
								}
							},
						},
					},
					flags: flags,
				})

				// The server must continue to ACK the Finished flight even after
				// receiving application data from the client.
				testCases = append(testCases, testCase{
					protocol: dtls,
					testType: serverTest,
					name:     "DTLS-Retransmit-Server-ACKFinishedAfterAppData" + suffix,
					config: Config{
						MaxVersion: vers.version,
						Bugs: ProtocolBugs{
							// WriteFlightDTLS will handle consuming ACKs.
							SkipImplicitACKRead: true,
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if next[len(next)-1].Type != typeFinished {
									c.WriteFlight(next)
									return
								}

								// Write Finished. The shim should ACK it immediately.
								c.WriteFlight(next)
								c.ReadACK(c.InEpoch())

								// Exchange some application data.
								msg := []byte("hello")
								c.WriteAppData(c.OutEpoch(), msg)
								c.ReadAppData(c.InEpoch(), expectedReply(msg))

								// Act as if the ACK was dropped and retransmit Finished.
								// The shim should process the retransmit from epoch 2 and
								// ACK, although it has already received data at epoch 3.
								c.WriteFlight(next)
								ackTimeout := useTimeouts[0] / 4
								c.AdvanceClock(ackTimeout)
								c.ReadACK(c.InEpoch())

								// Partially retransmit Finished. The shim should continue
								// to ACK.
								c.WriteFragments([]DTLSFragment{next[0].Fragment(0, 1)})
								c.WriteFragments([]DTLSFragment{next[0].Fragment(1, 1)})
								c.AdvanceClock(ackTimeout)
								c.ReadACK(c.InEpoch())

								// Eventually, the shim assumes we have received the ACK
								// and drops epoch 2. Retransmits now go unanswered.
								c.AdvanceClock(dtlsPrevEpochExpiration)
								c.WriteFlight(next)
							},
						},
					},
					// Disable tickets on the shim to avoid NewSessionTicket
					// interfering with the test callback.
					flags: slices.Concat(flags, []string{"-no-ticket"}),
				})

				// As a client, the shim must tolerate ACKs in response to its
				// initial ClientHello, but it will not process them because the
				// version is not yet known. The second ClientHello, in response
				// to HelloRetryRequest, however, is ACKed.
				//
				// The shim must additionally process ACKs and retransmit its
				// Finished flight, possibly interleaved with application data.
				// (The server may send half-RTT data without Finished.)
				testCases = append(testCases, testCase{
					protocol: dtls,
					name:     "DTLS-Retransmit-Client" + suffix,
					config: Config{
						MaxVersion: vers.version,
						// Require a client certificate, so the Finished flight
						// is large.
						ClientAuth: RequireAnyClientCert,
						Bugs: ProtocolBugs{
							SendHelloRetryRequestCookie: []byte("cookie"), // Send HelloRetryRequest
							MaxPacketLength:             512,
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if len(received) == 0 || received[0].Type != typeClientHello {
									// We test post-handshake flights separately.
									c.WriteFlight(next)
									return
								}

								// This is either HelloRetryRequest in response to ClientHello1,
								// or ServerHello..Finished in response to ClientHello2.
								first := records[0]
								if len(prev) == 0 {
									// This is HelloRetryRequest in response to ClientHello1. The client
									// will accept the ACK, but it will ignore it. Do not expect
									// retransmits to be impacted.
									first.MessageStartSequence = 0
									first.MessageStartOffset = 0
									first.MessageEndSequence = 0
									first.MessageEndOffset = 0
								}
								c.WriteACK(0, []DTLSRecordNumberInfo{first})
								c.AdvanceClock(useTimeouts[0])
								c.ReadRetransmit()
								c.WriteFlight(next)
							},
							ACKFlightDTLS: func(c *DTLSController, prev, received []DTLSMessage, records []DTLSRecordNumberInfo) {
								// The shim will process application data without an ACK.
								msg := []byte("hello")
								c.WriteAppData(c.OutEpoch(), msg)
								c.ReadAppData(c.InEpoch(), expectedReply(msg))

								// After a timeout, the shim will retransmit Finished.
								c.AdvanceClock(useTimeouts[0])
								c.ReadRetransmit()

								// Application data still flows.
								c.WriteAppData(c.OutEpoch(), msg)
								c.ReadAppData(c.InEpoch(), expectedReply(msg))

								// ACK part of the flight and check that retransmits
								// are updated.
								c.WriteACK(c.OutEpoch(), records[len(records)/3:2*len(records)/3])
								c.AdvanceClock(useTimeouts[1])
								records = c.ReadRetransmit()

								// ACK the rest. Retransmits should stop.
								c.WriteACK(c.OutEpoch(), records)
								for _, t := range useTimeouts[2:] {
									c.AdvanceClock(t)
								}
							},
						},
					},
					shimCertificate: &rsaChainCertificate,
					flags:           slices.Concat(flags, []string{"-mtu", "512", "-curves", strconv.Itoa(int(CurveX25519MLKEM768))}),
				})

				// If the client never receives an ACK for the Finished flight, it
				// is eventually fatal.
				testCases = append(testCases, testCase{
					protocol: dtls,
					name:     "DTLS-Retransmit-Client-FinishedTimeout" + suffix,
					config: Config{
						MaxVersion: vers.version,
						Bugs: ProtocolBugs{
							ACKFlightDTLS: func(c *DTLSController, prev, received []DTLSMessage, records []DTLSRecordNumberInfo) {
								for _, t := range useTimeouts[:len(useTimeouts)-1] {
									c.AdvanceClock(t)
									c.ReadRetransmit()
								}
								c.AdvanceClock(useTimeouts[len(useTimeouts)-1])
							},
						},
					},
					flags:         flags,
					shouldFail:    true,
					expectedError: ":READ_TIMEOUT_EXPIRED:",
				})

				// Neither post-handshake messages nor application data implicitly
				// ACK the Finished flight. The server may have sent either in
				// half-RTT data. Test that the client continues to retransmit
				// despite this.
				testCases = append(testCases, testCase{
					protocol: dtls,
					name:     "DTLS-Retransmit-Client-NoImplictACKFinished" + suffix,
					config: Config{
						MaxVersion: vers.version,
						Bugs: ProtocolBugs{
							ACKFlightDTLS: func(c *DTLSController, prev, received []DTLSMessage, records []DTLSRecordNumberInfo) {
								// Merge the Finished flight into the NewSessionTicket.
								c.MergeIntoNextFlight()
							},
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if next[0].Type != typeNewSessionTicket {
									c.WriteFlight(next)
									return
								}
								if len(received) == 0 || received[0].Type != typeFinished {
									panic("Finished should be merged with NewSessionTicket")
								}
								// Merge NewSessionTicket into the KeyUpdate.
								if next[len(next)-1].Type != typeKeyUpdate {
									c.MergeIntoNextFlight()
									return
								}

								// Write NewSessionTicket and the KeyUpdate and
								// read the ACK.
								c.WriteFlight(next)
								ackTimeout := useTimeouts[0] / 4
								c.AdvanceClock(ackTimeout)
								c.ReadACK(c.InEpoch())

								// The retransmit timer is still running.
								c.AdvanceClock(useTimeouts[0] - ackTimeout)
								c.ReadRetransmit()

								// Application data can flow at the old epoch.
								msg := []byte("test")
								c.WriteAppData(c.OutEpoch()-1, msg)
								c.ReadAppData(c.InEpoch(), expectedReply(msg))

								// The retransmit timer is still running.
								c.AdvanceClock(useTimeouts[1])
								c.ReadRetransmit()

								// Advance the shim to the next epoch.
								c.WriteAppData(c.OutEpoch(), msg)
								c.ReadAppData(c.InEpoch(), expectedReply(msg))

								// The retransmit timer is still running. The shim
								// actually could implicitly ACK at this point, but
								// RFC 9147 does not list this as an implicit ACK.
								c.AdvanceClock(useTimeouts[2])
								c.ReadRetransmit()

								// Finally ACK the final flight. Now the shim will
								// stop the timer.
								c.WriteACK(c.OutEpoch(), records)
								c.ExpectNoNextTimeout()
							},
						},
					},
					sendKeyUpdates:   1,
					keyUpdateRequest: keyUpdateNotRequested,
					flags:            flags,
				})

				// If the server never receives an ACK for NewSessionTicket, it
				// is eventually fatal.
				testCases = append(testCases, testCase{
					testType: serverTest,
					protocol: dtls,
					name:     "DTLS-Retransmit-Server-NewSessionTicketTimeout" + suffix,
					config: Config{
						MaxVersion: vers.version,
						Bugs: ProtocolBugs{
							ACKFlightDTLS: handleNewSessionTicket(func(c *DTLSController, prev, received []DTLSMessage, records []DTLSRecordNumberInfo) {
								if received[0].Type != typeNewSessionTicket {
									c.WriteACK(c.OutEpoch(), records)
									return
								}
								// Time the peer out.
								for _, t := range useTimeouts[:len(useTimeouts)-1] {
									c.AdvanceClock(t)
									c.ReadRetransmit()
								}
								c.AdvanceClock(useTimeouts[len(useTimeouts)-1])
							}),
						},
					},
					flags:         flags,
					shouldFail:    true,
					expectedError: ":READ_TIMEOUT_EXPIRED:",
				})

				// If generating the reply to a flight takes time (generating a
				// CertificateVerify for a client certificate), the shim should
				// send an ACK.
				testCases = append(testCases, testCase{
					protocol: dtls,
					name:     "DTLS-Retransmit-SlowReplyGeneration" + suffix,
					config: Config{
						MaxVersion: vers.version,
						ClientAuth: RequireAnyClientCert,
						Bugs: ProtocolBugs{
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								c.WriteFlight(next)
								if next[0].Type == typeServerHello {
									// The shim will reply with Certificate..Finished, but
									// take time to do so. In that time, it should schedule
									// an ACK so the runner knows not to retransmit.
									c.ReadACK(c.InEpoch())
								}
							},
						},
					},
					shimCertificate: &rsaCertificate,
					// Simulate it taking time to generate the reply.
					flags: slices.Concat(flags, []string{"-private-key-delay-ms", strconv.Itoa(int(useTimeouts[0].Milliseconds()))}),
				})

				// BoringSSL's ACK policy may schedule both retransmit and ACK
				// timers in parallel.
				//
				// TODO(crbug.com/42290594): This is only possible during the
				// handshake because we're willing to ACK old flights without
				// trying to distinguish these cases. However, post-handshake
				// messages will exercise this, so that may be a better version
				// of this test. In-handshake, it's kind of a waste to ACK this,
				// so maybe we should stop.
				testCases = append(testCases, testCase{
					protocol: dtls,
					name:     "DTLS-Retransmit-BothTimers" + suffix,
					config: Config{
						MaxVersion: vers.version,
						Bugs: ProtocolBugs{
							// Arrange for there to be two server flights.
							SendHelloRetryRequestCookie: []byte("cookie"),
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if next[0].Sequence == 0 || next[0].Type != typeServerHello {
									// Send the first flight (HelloRetryRequest) as-is,
									// as well as any post-handshake flights.
									c.WriteFlight(next)
									return
								}

								// The shim just send the ClientHello2 and is
								// waiting for ServerHello..Finished. If it hears
								// nothing, it will retransmit ClientHello2 on the
								// assumption the packet was lost.
								c.ExpectNextTimeout(useTimeouts[0])

								// Retransmit a portion of HelloRetryRequest.
								c.WriteFragments([]DTLSFragment{prev[0].Fragment(0, 1)})

								// The shim does not actually need to ACK this,
								// but BoringSSL does. Now both timers are active.
								// Fire the first...
								c.ExpectNextTimeout(useTimeouts[0] / 4)
								c.AdvanceClock(useTimeouts[0] / 4)
								c.ReadACK(0)

								// ...followed by the second.
								c.ExpectNextTimeout(3 * useTimeouts[0] / 4)
								c.AdvanceClock(3 * useTimeouts[0] / 4)
								c.ReadRetransmit()

								// The shim is now set for the next retransmit.
								c.ExpectNextTimeout(useTimeouts[1])

								// Start the ACK timer again.
								c.WriteFragments([]DTLSFragment{prev[0].Fragment(0, 1)})
								c.ExpectNextTimeout(useTimeouts[1] / 4)

								// Expire both timers at once.
								c.AdvanceClock(useTimeouts[1])
								c.ReadACK(0)
								c.ReadRetransmit()

								c.WriteFlight(next)
							},
						},
					},
					flags: flags,
				})

				testCases = append(testCases, testCase{
					protocol: dtls,
					name:     "DTLS-Retransmit-Client-ACKPostHandshake" + suffix,
					config: Config{
						MaxVersion: vers.version,
						Bugs: ProtocolBugs{
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if next[0].Type != typeNewSessionTicket {
									c.WriteFlight(next)
									return
								}

								// The test should try to send two NewSessionTickets in a row.
								if len(next) != 2 {
									panic("unexpected message count")
								}

								// Send part of first ticket post-handshake message.
								first0, second0 := next[0].Split(len(next[0].Data) / 2)
								first1, second1 := next[1].Split(len(next[1].Data) / 2)
								c.WriteFragments([]DTLSFragment{first0})

								// The shim should ACK on a timer.
								c.ExpectNextTimeout(useTimeouts[0] / 4)
								c.AdvanceClock(useTimeouts[0] / 4)
								c.ReadACK(c.InEpoch())

								// The shim is just waiting for us to retransmit.
								c.ExpectNoNextTimeout()

								// Send some more fragments.
								c.WriteFragments([]DTLSFragment{first0, second1})

								// The shim should ACK, again on a timer.
								c.ExpectNextTimeout(useTimeouts[0] / 4)
								c.AdvanceClock(useTimeouts[0] / 4)
								c.ReadACK(c.InEpoch())
								c.ExpectNoNextTimeout()

								// Finish up both messages. We implicitly test if shim
								// processed these messages by checking that it returned a new
								// session.
								c.WriteFragments([]DTLSFragment{first1, second0})

								// The shim should ACK again, once the timer expires.
								//
								// TODO(crbug.com/42290594): Should the shim ACK immediately?
								// Otherwise KeyUpdates are delayed, which will complicated
								// downstream testing.
								c.ExpectNextTimeout(useTimeouts[0] / 4)
								c.AdvanceClock(useTimeouts[0] / 4)
								c.ReadACK(c.InEpoch())
								c.ExpectNoNextTimeout()
							},
						},
					},
					flags: flags,
				})

				testCases = append(testCases, testCase{
					protocol: dtls,
					name:     "DTLS-Retransmit-Client-ACKPostHandshakeTwice" + suffix,
					config: Config{
						MaxVersion: vers.version,
						Bugs: ProtocolBugs{
							WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
								if next[0].Type != typeNewSessionTicket {
									c.WriteFlight(next)
									return
								}

								// The test should try to send two NewSessionTickets in a row.
								if len(next) != 2 {
									panic("unexpected message count")
								}

								// Send the flight. The shim should ACK it.
								c.WriteFlight(next)
								c.AdvanceClock(useTimeouts[0] / 4)
								c.ReadACK(c.InEpoch())
								c.ExpectNoNextTimeout()

								// Retransmit the flight, as if we lost the ACK. The shim should
								// ACK again.
								c.WriteFlight(next)
								c.AdvanceClock(useTimeouts[0] / 4)
								c.ReadACK(c.InEpoch())
								c.ExpectNoNextTimeout()
							},
						},
					},
					flags: flags,
				})
			}
		}
	}

	// Test that the final Finished retransmitting isn't
	// duplicated if the peer badly fragments everything.
	testCases = append(testCases, testCase{
		testType: serverTest,
		protocol: dtls,
		name:     "DTLS-RetransmitFinished-Fragmented",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				MaxHandshakeRecordLength: 2,
				ACKFlightDTLS: func(c *DTLSController, prev, received []DTLSMessage, records []DTLSRecordNumberInfo) {
					c.WriteFlight(prev)
					c.ReadRetransmit()
				},
			},
		},
		flags: []string{"-async"},
	})

	// If the shim sends the last Finished (server full or client resume
	// handshakes), it must retransmit that Finished when it sees a
	// post-handshake penultimate Finished from the runner. The above tests
	// cover this. Conversely, if the shim sends the penultimate Finished
	// (client full or server resume), test that it does not retransmit.
	testCases = append(testCases, testCase{
		protocol: dtls,
		testType: clientTest,
		name:     "DTLS-StrayRetransmitFinished-ClientFull",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
					c.WriteFlight(next)
					for _, msg := range next {
						if msg.Type == typeFinished {
							c.WriteFlight([]DTLSMessage{msg})
						}
					}
				},
			},
		},
	})
	testCases = append(testCases, testCase{
		protocol: dtls,
		testType: serverTest,
		name:     "DTLS-StrayRetransmitFinished-ServerResume",
		config: Config{
			MaxVersion: VersionTLS12,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
					c.WriteFlight(next)
					for _, msg := range next {
						if msg.Type == typeFinished {
							c.WriteFlight([]DTLSMessage{msg})
						}
					}
				},
			},
		},
		resumeSession: true,
	})
}

func addDTLSReorderTests() {
	for _, vers := range allVersions(dtls) {
		testCases = append(testCases, testCase{
			protocol: dtls,
			name:     "ReorderHandshakeFragments-Small-DTLS-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
				Bugs: ProtocolBugs{
					ReorderHandshakeFragments: true,
					// Small enough that every handshake message is
					// fragmented.
					MaxHandshakeRecordLength: 2,
				},
			},
		})
		testCases = append(testCases, testCase{
			protocol: dtls,
			name:     "ReorderHandshakeFragments-Large-DTLS-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
				Bugs: ProtocolBugs{
					ReorderHandshakeFragments: true,
					// Large enough that no handshake message is
					// fragmented.
					MaxHandshakeRecordLength: 2048,
				},
			},
		})
		testCases = append(testCases, testCase{
			protocol: dtls,
			name:     "MixCompleteMessageWithFragments-DTLS-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
				Bugs: ProtocolBugs{
					ReorderHandshakeFragments:       true,
					MixCompleteMessageWithFragments: true,
					MaxHandshakeRecordLength:        2,
				},
			},
		})
	}
}

func addExportKeyingMaterialTests() {
	for _, vers := range tlsVersions {
		testCases = append(testCases, testCase{
			name: "ExportKeyingMaterial-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
			},
			// Test the exporter in both initial and resumption
			// handshakes.
			resumeSession:        true,
			exportKeyingMaterial: 1024,
			exportLabel:          "label",
			exportContext:        "context",
			useExportContext:     true,
		})
		testCases = append(testCases, testCase{
			name: "ExportKeyingMaterial-NoContext-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
			},
			exportKeyingMaterial: 1024,
		})
		testCases = append(testCases, testCase{
			name: "ExportKeyingMaterial-EmptyContext-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
			},
			exportKeyingMaterial: 1024,
			useExportContext:     true,
		})
		testCases = append(testCases, testCase{
			name: "ExportKeyingMaterial-Small-" + vers.name,
			config: Config{
				MaxVersion: vers.version,
			},
			exportKeyingMaterial: 1,
			exportLabel:          "label",
			exportContext:        "context",
			useExportContext:     true,
		})

		if vers.version >= VersionTLS13 {
			// Test the exporters do not work while the client is
			// sending 0-RTT data.
			testCases = append(testCases, testCase{
				name: "NoEarlyKeyingMaterial-Client-InEarlyData-" + vers.name,
				config: Config{
					MaxVersion: vers.version,
				},
				resumeSession: true,
				earlyData:     true,
				flags: []string{
					"-on-resume-export-keying-material", "1024",
					"-on-resume-export-label", "label",
					"-on-resume-export-context", "context",
				},
				shouldFail:    true,
				expectedError: ":HANDSHAKE_NOT_COMPLETE:",
			})

			// Test the normal exporter on the server in half-RTT.
			testCases = append(testCases, testCase{
				testType: serverTest,
				name:     "ExportKeyingMaterial-Server-HalfRTT-" + vers.name,
				config: Config{
					MaxVersion: vers.version,
					Bugs: ProtocolBugs{
						// The shim writes exported data immediately after
						// the handshake returns, so disable the built-in
						// early data test.
						SendEarlyData:     [][]byte{},
						ExpectHalfRTTData: [][]byte{},
					},
				},
				resumeSession:        true,
				earlyData:            true,
				exportKeyingMaterial: 1024,
				exportLabel:          "label",
				exportContext:        "context",
				useExportContext:     true,
			})
		}
	}

	// Exporters work during a False Start.
	testCases = append(testCases, testCase{
		name: "ExportKeyingMaterial-FalseStart",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			NextProtos:   []string{"foo"},
			Bugs: ProtocolBugs{
				ExpectFalseStart: true,
			},
		},
		flags: []string{
			"-false-start",
			"-advertise-alpn", "\x03foo",
			"-expect-alpn", "foo",
		},
		shimWritesFirst:      true,
		exportKeyingMaterial: 1024,
		exportLabel:          "label",
		exportContext:        "context",
		useExportContext:     true,
	})

	// Exporters do not work in the middle of a renegotiation. Test this by
	// triggering the exporter after every SSL_read call and configuring the
	// shim to run asynchronously.
	testCases = append(testCases, testCase{
		name: "ExportKeyingMaterial-Renegotiate",
		config: Config{
			MaxVersion: VersionTLS12,
		},
		renegotiate: 1,
		flags: []string{
			"-async",
			"-use-exporter-between-reads",
			"-renegotiate-freely",
			"-expect-total-renegotiations", "1",
		},
		shouldFail:    true,
		expectedError: "failed to export keying material",
	})
}

func addExportTrafficSecretsTests() {
	for _, cipherSuite := range []testCipherSuite{
		// Test a SHA-256 and SHA-384 based cipher suite.
		{"AEAD-AES128-GCM-SHA256", TLS_AES_128_GCM_SHA256},
		{"AEAD-AES256-GCM-SHA384", TLS_AES_256_GCM_SHA384},
	} {
		testCases = append(testCases, testCase{
			name: "ExportTrafficSecrets-" + cipherSuite.name,
			config: Config{
				MinVersion:   VersionTLS13,
				CipherSuites: []uint16{cipherSuite.id},
			},
			exportTrafficSecrets: true,
		})
	}
}

func addTLSUniqueTests() {
	for _, isClient := range []bool{false, true} {
		for _, isResumption := range []bool{false, true} {
			for _, hasEMS := range []bool{false, true} {
				var suffix string
				if isResumption {
					suffix = "Resume-"
				} else {
					suffix = "Full-"
				}

				if hasEMS {
					suffix += "EMS-"
				} else {
					suffix += "NoEMS-"
				}

				if isClient {
					suffix += "Client"
				} else {
					suffix += "Server"
				}

				test := testCase{
					name:          "TLSUnique-" + suffix,
					testTLSUnique: true,
					config: Config{
						MaxVersion: VersionTLS12,
						Bugs: ProtocolBugs{
							NoExtendedMasterSecret: !hasEMS,
						},
					},
				}

				if isResumption {
					test.resumeSession = true
					test.resumeConfig = &Config{
						MaxVersion: VersionTLS12,
						Bugs: ProtocolBugs{
							NoExtendedMasterSecret: !hasEMS,
						},
					}
				}

				if isResumption && !hasEMS {
					test.shouldFail = true
					test.expectedError = "failed to get tls-unique"
				}

				testCases = append(testCases, test)
			}
		}
	}
}

func addCustomExtensionTests() {
	// Test an unknown extension from the server.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "UnknownExtension-Client",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				CustomExtension: "custom extension",
			},
		},
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_EXTENSION:",
		expectedLocalError: "remote error: unsupported extension",
	})
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "UnknownExtension-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				CustomExtension: "custom extension",
			},
		},
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_EXTENSION:",
		expectedLocalError: "remote error: unsupported extension",
	})
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "UnknownUnencryptedExtension-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				CustomUnencryptedExtension: "custom extension",
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_EXTENSION:",
		// The shim must send an alert, but alerts at this point do not
		// get successfully decrypted by the runner.
		expectedLocalError: "local error: bad record MAC",
	})
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "UnexpectedUnencryptedExtension-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendUnencryptedALPN: "foo",
			},
		},
		flags: []string{
			"-advertise-alpn", "\x03foo\x03bar",
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_EXTENSION:",
		// The shim must send an alert, but alerts at this point do not
		// get successfully decrypted by the runner.
		expectedLocalError: "local error: bad record MAC",
	})

	// Test a known but unoffered extension from the server.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "UnofferedExtension-Client",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SendALPN: "alpn",
			},
		},
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_EXTENSION:",
		expectedLocalError: "remote error: unsupported extension",
	})
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "UnofferedExtension-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendALPN: "alpn",
			},
		},
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_EXTENSION:",
		expectedLocalError: "remote error: unsupported extension",
	})
}

func addRSAClientKeyExchangeTests() {
	for bad := RSABadValue(1); bad < NumRSABadValues; bad++ {
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     fmt.Sprintf("BadRSAClientKeyExchange-%d", bad),
			config: Config{
				// Ensure the ClientHello version and final
				// version are different, to detect if the
				// server uses the wrong one.
				MaxVersion:   VersionTLS11,
				CipherSuites: []uint16{TLS_RSA_WITH_AES_128_CBC_SHA},
				Bugs: ProtocolBugs{
					BadRSAClientKeyExchange: bad,
				},
			},
			shouldFail:    true,
			expectedError: ":DECRYPTION_FAILED_OR_BAD_RECORD_MAC:",
		})
	}

	// The server must compare whatever was in ClientHello.version for the
	// RSA premaster.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SendClientVersion-RSA",
		config: Config{
			CipherSuites: []uint16{TLS_RSA_WITH_AES_128_GCM_SHA256},
			Bugs: ProtocolBugs{
				SendClientVersion: 0x1234,
			},
		},
		flags: []string{"-max-version", strconv.Itoa(VersionTLS12)},
	})
}

var testCurves = []struct {
	name string
	id   CurveID
}{
	{"P-224", CurveP224},
	{"P-256", CurveP256},
	{"P-384", CurveP384},
	{"P-521", CurveP521},
	{"X25519", CurveX25519},
	{"Kyber", CurveX25519Kyber768},
	{"MLKEM", CurveX25519MLKEM768},
}

const bogusCurve = 0x1234

func isPqGroup(r CurveID) bool {
	return r == CurveX25519Kyber768 || r == CurveX25519MLKEM768
}

func isECDHGroup(r CurveID) bool {
	return r == CurveP224 || r == CurveP256 || r == CurveP384 || r == CurveP521
}

func isX25519Group(r CurveID) bool {
	return r == CurveX25519 || r == CurveX25519Kyber768 || r == CurveX25519MLKEM768
}

func addCurveTests() {
	// A set of cipher suites that ensures some curve-using mode is used.
	// Without this, servers may fall back to RSA key exchange.
	ecdheCiphers := []uint16{
		TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
		TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
		TLS_AES_256_GCM_SHA384,
	}

	for _, curve := range testCurves {
		for _, ver := range tlsVersions {
			if isPqGroup(curve.id) && ver.version < VersionTLS13 {
				continue
			}
			for _, testType := range []testType{clientTest, serverTest} {
				suffix := fmt.Sprintf("%s-%s-%s", testType, curve.name, ver.name)

				testCases = append(testCases, testCase{
					testType: testType,
					name:     "CurveTest-" + suffix,
					config: Config{
						MaxVersion:       ver.version,
						CipherSuites:     ecdheCiphers,
						CurvePreferences: []CurveID{curve.id},
					},
					flags: append(
						[]string{"-expect-curve-id", strconv.Itoa(int(curve.id))},
						flagInts("-curves", shimConfig.AllCurves)...,
					),
					expectations: connectionExpectations{
						curveID: curve.id,
					},
				})

				badKeyShareLocalError := "remote error: illegal parameter"
				if testType == clientTest && ver.version >= VersionTLS13 {
					// If the shim is a TLS 1.3 client and the runner sends a bad
					// key share, the runner never reads the client's cleartext
					// alert because the runner has already started encrypting by
					// the time the client sees it.
					badKeyShareLocalError = "local error: bad record MAC"
				}

				testCases = append(testCases, testCase{
					testType: testType,
					name:     "CurveTest-Invalid-TruncateKeyShare-" + suffix,
					config: Config{
						MaxVersion:       ver.version,
						CipherSuites:     ecdheCiphers,
						CurvePreferences: []CurveID{curve.id},
						Bugs: ProtocolBugs{
							TruncateKeyShare: true,
						},
					},
					flags:              flagInts("-curves", shimConfig.AllCurves),
					shouldFail:         true,
					expectedError:      ":BAD_ECPOINT:",
					expectedLocalError: badKeyShareLocalError,
				})

				testCases = append(testCases, testCase{
					testType: testType,
					name:     "CurveTest-Invalid-PadKeyShare-" + suffix,
					config: Config{
						MaxVersion:       ver.version,
						CipherSuites:     ecdheCiphers,
						CurvePreferences: []CurveID{curve.id},
						Bugs: ProtocolBugs{
							PadKeyShare: true,
						},
					},
					flags:              flagInts("-curves", shimConfig.AllCurves),
					shouldFail:         true,
					expectedError:      ":BAD_ECPOINT:",
					expectedLocalError: badKeyShareLocalError,
				})

				if isECDHGroup(curve.id) {
					testCases = append(testCases, testCase{
						testType: testType,
						name:     "CurveTest-Invalid-Compressed-" + suffix,
						config: Config{
							MaxVersion:       ver.version,
							CipherSuites:     ecdheCiphers,
							CurvePreferences: []CurveID{curve.id},
							Bugs: ProtocolBugs{
								SendCompressedCoordinates: true,
							},
						},
						flags:              flagInts("-curves", shimConfig.AllCurves),
						shouldFail:         true,
						expectedError:      ":BAD_ECPOINT:",
						expectedLocalError: badKeyShareLocalError,
					})
					testCases = append(testCases, testCase{
						testType: testType,
						name:     "CurveTest-Invalid-NotOnCurve-" + suffix,
						config: Config{
							MaxVersion:       ver.version,
							CipherSuites:     ecdheCiphers,
							CurvePreferences: []CurveID{curve.id},
							Bugs: ProtocolBugs{
								ECDHPointNotOnCurve: true,
							},
						},
						flags:              flagInts("-curves", shimConfig.AllCurves),
						shouldFail:         true,
						expectedError:      ":BAD_ECPOINT:",
						expectedLocalError: badKeyShareLocalError,
					})
				}

				if isX25519Group(curve.id) {
					// Implementations should mask off the high order bit in X25519.
					testCases = append(testCases, testCase{
						testType: testType,
						name:     "CurveTest-SetX25519HighBit-" + suffix,
						config: Config{
							MaxVersion:       ver.version,
							CipherSuites:     ecdheCiphers,
							CurvePreferences: []CurveID{curve.id},
							Bugs: ProtocolBugs{
								SetX25519HighBit: true,
							},
						},
						flags: flagInts("-curves", shimConfig.AllCurves),
						expectations: connectionExpectations{
							curveID: curve.id,
						},
					})

					// Implementations should reject low order points.
					testCases = append(testCases, testCase{
						testType: testType,
						name:     "CurveTest-Invalid-LowOrderX25519Point-" + suffix,
						config: Config{
							MaxVersion:       ver.version,
							CipherSuites:     ecdheCiphers,
							CurvePreferences: []CurveID{curve.id},
							Bugs: ProtocolBugs{
								LowOrderX25519Point: true,
							},
						},
						flags:              flagInts("-curves", shimConfig.AllCurves),
						shouldFail:         true,
						expectedError:      ":BAD_ECPOINT:",
						expectedLocalError: badKeyShareLocalError,
					})
				}

				if curve.id == CurveX25519MLKEM768 && testType == serverTest {
					testCases = append(testCases, testCase{
						testType: testType,
						name:     "CurveTest-Invalid-MLKEMEncapKeyNotReduced-" + suffix,
						config: Config{
							MaxVersion:       ver.version,
							CipherSuites:     ecdheCiphers,
							CurvePreferences: []CurveID{curve.id},
							Bugs: ProtocolBugs{
								MLKEMEncapKeyNotReduced: true,
							},
						},
						flags:              flagInts("-curves", shimConfig.AllCurves),
						shouldFail:         true,
						expectedError:      ":BAD_ECPOINT:",
						expectedLocalError: badKeyShareLocalError,
					})
				}
			}
		}
	}

	// The server must be tolerant to bogus curves.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "UnknownCurve",
		config: Config{
			MaxVersion:       VersionTLS12,
			CipherSuites:     []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			CurvePreferences: []CurveID{bogusCurve, CurveP256},
		},
	})

	// The server must be tolerant to bogus curves.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "UnknownCurve-TLS13",
		config: Config{
			MaxVersion:       VersionTLS13,
			CurvePreferences: []CurveID{bogusCurve, CurveP256},
		},
	})

	// The server must not consider ECDHE ciphers when there are no
	// supported curves.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "NoSupportedCurves",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			Bugs: ProtocolBugs{
				NoSupportedCurves: true,
			},
		},
		shouldFail:    true,
		expectedError: ":NO_SHARED_CIPHER:",
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "NoSupportedCurves-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				NoSupportedCurves: true,
			},
		},
		shouldFail:    true,
		expectedError: ":NO_SHARED_GROUP:",
	})

	// The server must fall back to another cipher when there are no
	// supported curves.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "NoCommonCurves",
		config: Config{
			MaxVersion: VersionTLS12,
			CipherSuites: []uint16{
				TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
				TLS_RSA_WITH_AES_128_GCM_SHA256,
			},
			CurvePreferences: []CurveID{CurveP224},
		},
		expectations: connectionExpectations{
			cipher: TLS_RSA_WITH_AES_128_GCM_SHA256,
		},
	})

	// The client must reject bogus curves and disabled curves.
	testCases = append(testCases, testCase{
		name: "BadECDHECurve",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			Bugs: ProtocolBugs{
				SendCurve: bogusCurve,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_CURVE:",
	})
	testCases = append(testCases, testCase{
		name: "BadECDHECurve-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendCurve: bogusCurve,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_CURVE:",
	})

	testCases = append(testCases, testCase{
		name: "UnsupportedCurve",
		config: Config{
			MaxVersion:       VersionTLS12,
			CipherSuites:     []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			CurvePreferences: []CurveID{CurveP256},
			Bugs: ProtocolBugs{
				IgnorePeerCurvePreferences: true,
			},
		},
		flags:         []string{"-curves", strconv.Itoa(int(CurveP384))},
		shouldFail:    true,
		expectedError: ":WRONG_CURVE:",
	})

	testCases = append(testCases, testCase{
		// TODO(davidben): Add a TLS 1.3 version where
		// HelloRetryRequest requests an unsupported curve.
		name: "UnsupportedCurve-ServerHello-TLS13",
		config: Config{
			MaxVersion:       VersionTLS13,
			CurvePreferences: []CurveID{CurveP384},
			Bugs: ProtocolBugs{
				SendCurve: CurveP256,
			},
		},
		flags:         []string{"-curves", strconv.Itoa(int(CurveP384))},
		shouldFail:    true,
		expectedError: ":WRONG_CURVE:",
	})

	// The previous curve ID should be reported on TLS 1.2 resumption.
	testCases = append(testCases, testCase{
		name: "CurveID-Resume-Client",
		config: Config{
			MaxVersion:       VersionTLS12,
			CipherSuites:     []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			CurvePreferences: []CurveID{CurveX25519},
		},
		flags:         []string{"-expect-curve-id", strconv.Itoa(int(CurveX25519))},
		resumeSession: true,
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "CurveID-Resume-Server",
		config: Config{
			MaxVersion:       VersionTLS12,
			CipherSuites:     []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			CurvePreferences: []CurveID{CurveX25519},
		},
		flags:         []string{"-expect-curve-id", strconv.Itoa(int(CurveX25519))},
		resumeSession: true,
	})

	// TLS 1.3 allows resuming at a differet curve. If this happens, the new
	// one should be reported.
	testCases = append(testCases, testCase{
		name: "CurveID-Resume-Client-TLS13",
		config: Config{
			MaxVersion:       VersionTLS13,
			CurvePreferences: []CurveID{CurveX25519},
		},
		resumeConfig: &Config{
			MaxVersion:       VersionTLS13,
			CurvePreferences: []CurveID{CurveP256},
		},
		flags: []string{
			"-on-initial-expect-curve-id", strconv.Itoa(int(CurveX25519)),
			"-on-resume-expect-curve-id", strconv.Itoa(int(CurveP256)),
		},
		resumeSession: true,
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "CurveID-Resume-Server-TLS13",
		config: Config{
			MaxVersion:       VersionTLS13,
			CurvePreferences: []CurveID{CurveX25519},
		},
		resumeConfig: &Config{
			MaxVersion:       VersionTLS13,
			CurvePreferences: []CurveID{CurveP256},
		},
		flags: []string{
			"-on-initial-expect-curve-id", strconv.Itoa(int(CurveX25519)),
			"-on-resume-expect-curve-id", strconv.Itoa(int(CurveP256)),
		},
		resumeSession: true,
	})

	// Server-sent point formats are legal in TLS 1.2, but not in TLS 1.3.
	testCases = append(testCases, testCase{
		name: "PointFormat-ServerHello-TLS12",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SendSupportedPointFormats: []byte{pointFormatUncompressed},
			},
		},
	})
	testCases = append(testCases, testCase{
		name: "PointFormat-EncryptedExtensions-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendSupportedPointFormats: []byte{pointFormatUncompressed},
			},
		},
		shouldFail:    true,
		expectedError: ":ERROR_PARSING_EXTENSION:",
	})

	// Server-sent supported groups/curves are legal in TLS 1.3. They are
	// illegal in TLS 1.2, but some servers send them anyway, so we must
	// tolerate them.
	testCases = append(testCases, testCase{
		name: "SupportedCurves-ServerHello-TLS12",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SendServerSupportedCurves: true,
			},
		},
	})
	testCases = append(testCases, testCase{
		name: "SupportedCurves-EncryptedExtensions-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendServerSupportedCurves: true,
			},
		},
	})

	// Test that we tolerate unknown point formats, as long as
	// pointFormatUncompressed is present. Limit ciphers to ECDHE ciphers to
	// check they are still functional.
	testCases = append(testCases, testCase{
		name: "PointFormat-Client-Tolerance",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SendSupportedPointFormats: []byte{42, pointFormatUncompressed, 99, pointFormatCompressedPrime},
			},
		},
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "PointFormat-Server-Tolerance",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256},
			Bugs: ProtocolBugs{
				SendSupportedPointFormats: []byte{42, pointFormatUncompressed, 99, pointFormatCompressedPrime},
			},
		},
	})

	// Test TLS 1.2 does not require the point format extension to be
	// present.
	testCases = append(testCases, testCase{
		name: "PointFormat-Client-Missing",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256},
			Bugs: ProtocolBugs{
				SendSupportedPointFormats: []byte{},
			},
		},
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "PointFormat-Server-Missing",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256},
			Bugs: ProtocolBugs{
				SendSupportedPointFormats: []byte{},
			},
		},
	})

	// If the point format extension is present, uncompressed points must be
	// offered. BoringSSL requires this whether or not ECDHE is used.
	testCases = append(testCases, testCase{
		name: "PointFormat-Client-MissingUncompressed",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SendSupportedPointFormats: []byte{pointFormatCompressedPrime},
			},
		},
		shouldFail:    true,
		expectedError: ":ERROR_PARSING_EXTENSION:",
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "PointFormat-Server-MissingUncompressed",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SendSupportedPointFormats: []byte{pointFormatCompressedPrime},
			},
		},
		shouldFail:    true,
		expectedError: ":ERROR_PARSING_EXTENSION:",
	})

	// Post-quantum groups require TLS 1.3.
	for _, curve := range testCurves {
		if !isPqGroup(curve.id) {
			continue
		}

		// Post-quantum groups should not be offered by a TLS 1.2 client.
		testCases = append(testCases, testCase{
			name: "TLS12ClientShouldNotOffer-" + curve.name,
			config: Config{
				Bugs: ProtocolBugs{
					FailIfPostQuantumOffered: true,
				},
			},
			flags: []string{
				"-max-version", strconv.Itoa(VersionTLS12),
				"-curves", strconv.Itoa(int(curve.id)),
				"-curves", strconv.Itoa(int(CurveX25519)),
			},
		})

		// Post-quantum groups should not be selected by a TLS 1.2 server.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "TLS12ServerShouldNotSelect-" + curve.name,
			flags: []string{
				"-max-version", strconv.Itoa(VersionTLS12),
				"-curves", strconv.Itoa(int(curve.id)),
				"-curves", strconv.Itoa(int(CurveX25519)),
			},
			expectations: connectionExpectations{
				curveID: CurveX25519,
			},
		})

		// If a TLS 1.2 server selects a post-quantum group anyway, the client
		// should not accept it.
		testCases = append(testCases, testCase{
			name: "ClientShouldNotAllowInTLS12-" + curve.name,
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					SendCurve: curve.id,
				},
			},
			flags: []string{
				"-curves", strconv.Itoa(int(curve.id)),
				"-curves", strconv.Itoa(int(CurveX25519)),
			},
			shouldFail:         true,
			expectedError:      ":WRONG_CURVE:",
			expectedLocalError: "remote error: illegal parameter",
		})
	}

	// ML-KEM and Kyber should not be offered by default as a client.
	testCases = append(testCases, testCase{
		name: "PostQuantumNotEnabledByDefaultInClients",
		config: Config{
			MinVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				FailIfPostQuantumOffered: true,
			},
		},
	})

	// If ML-KEM is offered, both X25519 and ML-KEM should have a key-share.
	testCases = append(testCases, testCase{
		name: "NotJustMLKEMKeyShare",
		config: Config{
			MinVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				ExpectedKeyShares: []CurveID{CurveX25519MLKEM768, CurveX25519},
			},
		},
		flags: []string{
			"-curves", strconv.Itoa(int(CurveX25519MLKEM768)),
			"-curves", strconv.Itoa(int(CurveX25519)),
			"-expect-curve-id", strconv.Itoa(int(CurveX25519MLKEM768)),
		},
	})

	// ... and the other way around
	testCases = append(testCases, testCase{
		name: "MLKEMKeyShareIncludedSecond",
		config: Config{
			MinVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				ExpectedKeyShares: []CurveID{CurveX25519, CurveX25519MLKEM768},
			},
		},
		flags: []string{
			"-curves", strconv.Itoa(int(CurveX25519)),
			"-curves", strconv.Itoa(int(CurveX25519MLKEM768)),
			"-expect-curve-id", strconv.Itoa(int(CurveX25519)),
		},
	})

	// ... and even if there's another curve in the middle because it's the
	// first classical and first post-quantum "curves" that get key shares
	// included.
	testCases = append(testCases, testCase{
		name: "MLKEMKeyShareIncludedThird",
		config: Config{
			MinVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				ExpectedKeyShares: []CurveID{CurveX25519, CurveX25519MLKEM768},
			},
		},
		flags: []string{
			"-curves", strconv.Itoa(int(CurveX25519)),
			"-curves", strconv.Itoa(int(CurveP256)),
			"-curves", strconv.Itoa(int(CurveX25519MLKEM768)),
			"-expect-curve-id", strconv.Itoa(int(CurveX25519)),
		},
	})

	// If ML-KEM is the only configured curve, the key share is sent.
	testCases = append(testCases, testCase{
		name: "JustConfiguringMLKEMWorks",
		config: Config{
			MinVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				ExpectedKeyShares: []CurveID{CurveX25519MLKEM768},
			},
		},
		flags: []string{
			"-curves", strconv.Itoa(int(CurveX25519MLKEM768)),
			"-expect-curve-id", strconv.Itoa(int(CurveX25519MLKEM768)),
		},
	})

	// If both ML-KEM and Kyber are configured, only the preferred one's
	// key share should be sent.
	testCases = append(testCases, testCase{
		name: "BothMLKEMAndKyber",
		config: Config{
			MinVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				ExpectedKeyShares: []CurveID{CurveX25519MLKEM768},
			},
		},
		flags: []string{
			"-curves", strconv.Itoa(int(CurveX25519MLKEM768)),
			"-curves", strconv.Itoa(int(CurveX25519Kyber768)),
			"-expect-curve-id", strconv.Itoa(int(CurveX25519MLKEM768)),
		},
	})

	// As a server, ML-KEM is not yet supported by default.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "PostQuantumNotEnabledByDefaultForAServer",
		config: Config{
			MinVersion:       VersionTLS13,
			CurvePreferences: []CurveID{CurveX25519MLKEM768, CurveX25519Kyber768, CurveX25519},
			DefaultCurves:    []CurveID{CurveX25519MLKEM768, CurveX25519Kyber768},
		},
		flags: []string{
			"-server-preference",
			"-expect-curve-id", strconv.Itoa(int(CurveX25519)),
		},
	})

	// In TLS 1.2, the curve list is also used to signal ECDSA curves.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "CheckECDSACurve-TLS12",
		config: Config{
			MinVersion:       VersionTLS12,
			MaxVersion:       VersionTLS12,
			CurvePreferences: []CurveID{CurveP384},
		},
		shimCertificate: &ecdsaP256Certificate,
		shouldFail:      true,
		expectedError:   ":WRONG_CURVE:",
	})

	// If the ECDSA certificate is ineligible due to a curve mismatch, the
	// server may still consider a PSK cipher suite.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "CheckECDSACurve-PSK-TLS12",
		config: Config{
			MinVersion: VersionTLS12,
			MaxVersion: VersionTLS12,
			CipherSuites: []uint16{
				TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
				TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA,
			},
			CurvePreferences:     []CurveID{CurveP384},
			PreSharedKey:         []byte("12345"),
			PreSharedKeyIdentity: "luggage combo",
		},
		shimCertificate: &ecdsaP256Certificate,
		expectations: connectionExpectations{
			cipher: TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA,
		},
		flags: []string{
			"-psk", "12345",
			"-psk-identity", "luggage combo",
		},
	})

	// In TLS 1.3, the curve list only controls ECDH.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "CheckECDSACurve-NotApplicable-TLS13",
		config: Config{
			MinVersion:       VersionTLS13,
			MaxVersion:       VersionTLS13,
			CurvePreferences: []CurveID{CurveP384},
		},
		shimCertificate: &ecdsaP256Certificate,
	})
}

func addTLS13RecordTests() {
	for _, protocol := range []protocol{tls, dtls} {
		testCases = append(testCases, testCase{
			protocol: protocol,
			name:     "TLS13-RecordPadding-" + protocol.String(),
			config: Config{
				MaxVersion: VersionTLS13,
				MinVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					RecordPadding: 10,
				},
			},
		})

		testCases = append(testCases, testCase{
			protocol: protocol,
			name:     "TLS13-EmptyRecords-" + protocol.String(),
			config: Config{
				MaxVersion: VersionTLS13,
				MinVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					OmitRecordContents: true,
				},
			},
			shouldFail:    true,
			expectedError: ":DECRYPTION_FAILED_OR_BAD_RECORD_MAC:",
		})

		testCases = append(testCases, testCase{
			protocol: protocol,
			name:     "TLS13-OnlyPadding-" + protocol.String(),
			config: Config{
				MaxVersion: VersionTLS13,
				MinVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					OmitRecordContents: true,
					RecordPadding:      10,
				},
			},
			shouldFail:    true,
			expectedError: ":DECRYPTION_FAILED_OR_BAD_RECORD_MAC:",
		})

		if protocol == tls {
			testCases = append(testCases, testCase{
				protocol: protocol,
				name:     "TLS13-WrongOuterRecord-" + protocol.String(),
				config: Config{
					MaxVersion: VersionTLS13,
					MinVersion: VersionTLS13,
					Bugs: ProtocolBugs{
						OuterRecordType: recordTypeHandshake,
					},
				},
				shouldFail:    true,
				expectedError: ":INVALID_OUTER_RECORD_TYPE:",
			})
		}
	}
}

func addSessionTicketTests() {
	testCases = append(testCases, testCase{
		// In TLS 1.2 and below, empty NewSessionTicket messages
		// mean the server changed its mind on sending a ticket.
		name: "SendEmptySessionTicket-TLS12",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SendEmptySessionTicket: true,
			},
		},
		flags: []string{"-expect-no-session"},
	})

	testCases = append(testCases, testCase{
		// In TLS 1.3, empty NewSessionTicket messages are not
		// allowed.
		name: "SendEmptySessionTicket-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendEmptySessionTicket: true,
			},
		},
		shouldFail:         true,
		expectedError:      ":DECODE_ERROR:",
		expectedLocalError: "remote error: error decoding message",
	})

	// Test that the server ignores unknown PSK modes.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "TLS13-SendUnknownModeSessionTicket-Server",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendPSKKeyExchangeModes: []byte{0x1a, pskDHEKEMode, 0x2a},
			},
		},
		resumeSession: true,
		expectations: connectionExpectations{
			version: VersionTLS13,
		},
	})

	// Test that the server does not send session tickets with no matching key exchange mode.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "TLS13-ExpectNoSessionTicketOnBadKEMode-Server",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendPSKKeyExchangeModes:  []byte{0x1a},
				ExpectNoNewSessionTicket: true,
			},
		},
	})

	// Test that the server does not accept a session with no matching key exchange mode.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "TLS13-SendBadKEModeSessionTicket-Server",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendPSKKeyExchangeModes: []byte{0x1a},
			},
		},
		resumeSession:        true,
		expectResumeRejected: true,
	})

	// Test that the server rejects ClientHellos with pre_shared_key but without
	// psk_key_exchange_modes.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "TLS13-SendNoKEMModesWithPSK-Server",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendPSKKeyExchangeModes: []byte{},
			},
		},
		resumeSession:      true,
		shouldFail:         true,
		expectedLocalError: "remote error: missing extension",
		expectedError:      ":MISSING_EXTENSION:",
	})

	// Test that the client ticket age is sent correctly.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "TLS13-TestValidTicketAge-Client",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				ExpectTicketAge: 10 * time.Second,
			},
		},
		resumeSession: true,
		flags: []string{
			"-resumption-delay", "10",
		},
	})

	// Test that the client ticket age is enforced.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "TLS13-TestBadTicketAge-Client",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				ExpectTicketAge: 1000 * time.Second,
			},
		},
		resumeSession:      true,
		shouldFail:         true,
		expectedLocalError: "tls: invalid ticket age",
	})

	// Test that the server's ticket age skew reporting works.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "TLS13-TicketAgeSkew-Forward",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendTicketAge: 15 * time.Second,
			},
		},
		resumeSession:        true,
		resumeRenewedSession: true,
		flags: []string{
			"-resumption-delay", "10",
			"-expect-ticket-age-skew", "5",
		},
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "TLS13-TicketAgeSkew-Backward",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendTicketAge: 5 * time.Second,
			},
		},
		resumeSession:        true,
		resumeRenewedSession: true,
		flags: []string{
			"-resumption-delay", "10",
			"-expect-ticket-age-skew", "-5",
		},
	})

	// Test that ticket age skew up to 60 seconds in either direction is accepted.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "TLS13-TicketAgeSkew-Forward-60-Accept",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendTicketAge: 70 * time.Second,
			},
		},
		resumeSession: true,
		earlyData:     true,
		flags: []string{
			"-resumption-delay", "10",
			"-expect-ticket-age-skew", "60",
		},
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "TLS13-TicketAgeSkew-Backward-60-Accept",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendTicketAge: 10 * time.Second,
			},
		},
		resumeSession: true,
		earlyData:     true,
		flags: []string{
			"-resumption-delay", "70",
			"-expect-ticket-age-skew", "-60",
		},
	})

	// Test that ticket age skew beyond 60 seconds in either direction is rejected.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "TLS13-TicketAgeSkew-Forward-61-Reject",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendTicketAge: 71 * time.Second,
			},
		},
		resumeSession:           true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			"-resumption-delay", "10",
			"-expect-ticket-age-skew", "61",
			"-on-resume-expect-early-data-reason", "ticket_age_skew",
		},
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "TLS13-TicketAgeSkew-Backward-61-Reject",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendTicketAge: 10 * time.Second,
			},
		},
		resumeSession:           true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			"-resumption-delay", "71",
			"-expect-ticket-age-skew", "-61",
			"-on-resume-expect-early-data-reason", "ticket_age_skew",
		},
	})

	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "TLS13-SendTicketEarlyDataSupport",
		config: Config{
			MaxVersion:       VersionTLS13,
			MaxEarlyDataSize: 16384,
		},
		flags: []string{
			"-enable-early-data",
			"-expect-ticket-supports-early-data",
		},
	})

	// Test that 0-RTT tickets are still recorded as such when early data is disabled overall.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "TLS13-SendTicketEarlyDataSupport-Disabled",
		config: Config{
			MaxVersion:       VersionTLS13,
			MaxEarlyDataSize: 16384,
		},
		flags: []string{
			"-expect-ticket-supports-early-data",
		},
	})

	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "TLS13-DuplicateTicketEarlyDataSupport",
		config: Config{
			MaxVersion:       VersionTLS13,
			MaxEarlyDataSize: 16384,
			Bugs: ProtocolBugs{
				DuplicateTicketEarlyData: true,
			},
		},
		shouldFail:         true,
		expectedError:      ":DUPLICATE_EXTENSION:",
		expectedLocalError: "remote error: illegal parameter",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "TLS13-ExpectTicketEarlyDataSupport",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				ExpectTicketEarlyData: true,
			},
		},
		flags: []string{
			"-enable-early-data",
		},
	})

	// Test that, in TLS 1.3, the server-offered NewSessionTicket lifetime
	// is honored.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "TLS13-HonorServerSessionTicketLifetime",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendTicketLifetime: 20 * time.Second,
			},
		},
		flags: []string{
			"-resumption-delay", "19",
		},
		resumeSession: true,
	})
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "TLS13-HonorServerSessionTicketLifetime-2",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendTicketLifetime: 20 * time.Second,
				// The client should not offer the expired session.
				ExpectNoTLS13PSK: true,
			},
		},
		flags: []string{
			"-resumption-delay", "21",
		},
		resumeSession:        true,
		expectResumeRejected: true,
	})

	for _, ver := range tlsVersions {
		// Prior to TLS 1.3, disabling session tickets enables session IDs.
		useStatefulResumption := ver.version < VersionTLS13

		// SSL_OP_NO_TICKET implies the server must not mint any tickets.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     ver.name + "-NoTicket-NoMint",
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Bugs: ProtocolBugs{
					ExpectNoNewSessionTicket: true,
					RequireSessionIDs:        useStatefulResumption,
				},
			},
			resumeSession: useStatefulResumption,
			flags:         []string{"-no-ticket"},
		})

		// SSL_OP_NO_TICKET implies the server must not accept any tickets.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     ver.name + "-NoTicket-NoAccept",
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
			},
			resumeSession:        true,
			expectResumeRejected: true,
			// Set SSL_OP_NO_TICKET on the second connection, after the first
			// has established tickets.
			flags: []string{"-on-resume-no-ticket"},
		})

		// SSL_OP_NO_TICKET implies the client must not offer ticket-based
		// sessions. The client not only should not send the session ticket
		// extension, but if the server echos the session ID, the client should
		// reject this.
		if ver.version < VersionTLS13 {
			testCases = append(testCases, testCase{
				name: ver.name + "-NoTicket-NoOffer",
				config: Config{
					MinVersion: ver.version,
					MaxVersion: ver.version,
				},
				resumeConfig: &Config{
					MinVersion: ver.version,
					MaxVersion: ver.version,
					Bugs: ProtocolBugs{
						ExpectNoTLS12TicketSupport: true,
						// Pretend to accept the session, even though the client
						// did not offer it. The client should reject this as
						// invalid. A buggy client will still fail because it
						// expects resumption, but with a different error.
						// Ideally, we would test this by actually resuming the
						// previous session, even though the client did not
						// provide a ticket.
						EchoSessionIDInFullHandshake: true,
					},
				},
				resumeSession:        true,
				expectResumeRejected: true,
				// Set SSL_OP_NO_TICKET on the second connection, after the first
				// has established tickets.
				flags:              []string{"-on-resume-no-ticket"},
				shouldFail:         true,
				expectedError:      ":SERVER_ECHOED_INVALID_SESSION_ID:",
				expectedLocalError: "remote error: illegal parameter",
			})
		}
	}
}

func addChangeCipherSpecTests() {
	// Test missing ChangeCipherSpecs.
	testCases = append(testCases, testCase{
		name: "SkipChangeCipherSpec-Client",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SkipChangeCipherSpec: true,
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_RECORD:",
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SkipChangeCipherSpec-Server",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SkipChangeCipherSpec: true,
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_RECORD:",
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SkipChangeCipherSpec-Server-NPN",
		config: Config{
			MaxVersion: VersionTLS12,
			NextProtos: []string{"bar"},
			Bugs: ProtocolBugs{
				SkipChangeCipherSpec: true,
			},
		},
		flags: []string{
			"-advertise-npn", "\x03foo\x03bar\x03baz",
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_RECORD:",
	})

	// Test synchronization between the handshake and ChangeCipherSpec.
	// Partial post-CCS handshake messages before ChangeCipherSpec should be
	// rejected. Test both with and without handshake packing to handle both
	// when the partial post-CCS message is in its own record and when it is
	// attached to the pre-CCS message.
	for _, packed := range []bool{false, true} {
		var suffix string
		if packed {
			suffix = "-Packed"
		}

		testCases = append(testCases, testCase{
			name: "FragmentAcrossChangeCipherSpec-Client" + suffix,
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					FragmentAcrossChangeCipherSpec: true,
					PackHandshakeFlight:            packed,
				},
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_RECORD:",
		})
		testCases = append(testCases, testCase{
			name: "FragmentAcrossChangeCipherSpec-Client-Resume" + suffix,
			config: Config{
				MaxVersion: VersionTLS12,
			},
			resumeSession: true,
			resumeConfig: &Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					FragmentAcrossChangeCipherSpec: true,
					PackHandshakeFlight:            packed,
				},
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_RECORD:",
		})
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "FragmentAcrossChangeCipherSpec-Server" + suffix,
			config: Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					FragmentAcrossChangeCipherSpec: true,
					PackHandshakeFlight:            packed,
				},
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_RECORD:",
		})
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "FragmentAcrossChangeCipherSpec-Server-Resume" + suffix,
			config: Config{
				MaxVersion: VersionTLS12,
			},
			resumeSession: true,
			resumeConfig: &Config{
				MaxVersion: VersionTLS12,
				Bugs: ProtocolBugs{
					FragmentAcrossChangeCipherSpec: true,
					PackHandshakeFlight:            packed,
				},
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_RECORD:",
		})
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "FragmentAcrossChangeCipherSpec-Server-NPN" + suffix,
			config: Config{
				MaxVersion: VersionTLS12,
				NextProtos: []string{"bar"},
				Bugs: ProtocolBugs{
					FragmentAcrossChangeCipherSpec: true,
					PackHandshakeFlight:            packed,
				},
			},
			flags: []string{
				"-advertise-npn", "\x03foo\x03bar\x03baz",
			},
			shouldFail:    true,
			expectedError: ":UNEXPECTED_RECORD:",
		})
	}

	// In TLS 1.2 resumptions, the client sends ClientHello in the first flight
	// and ChangeCipherSpec + Finished in the second flight. Test the server's
	// behavior when the Finished message is fragmented across not only
	// ChangeCipherSpec but also the flight boundary.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "PartialClientFinishedWithClientHello-TLS12-Resume",
		config: Config{
			MaxVersion: VersionTLS12,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				PartialClientFinishedWithClientHello: true,
			},
		},
		resumeSession:      true,
		shouldFail:         true,
		expectedError:      ":EXCESS_HANDSHAKE_DATA:",
		expectedLocalError: "remote error: unexpected message",
	})

	// In TLS 1.2 full handshakes without tickets, the server's first flight ends
	// with ServerHelloDone and the second flight is ChangeCipherSpec + Finished.
	// Test the client's behavior when the Finished message is fragmented across
	// not only ChangeCipherSpec but also the flight boundary.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "PartialFinishedWithServerHelloDone",
		config: Config{
			MaxVersion:             VersionTLS12,
			SessionTicketsDisabled: true,
			Bugs: ProtocolBugs{
				PartialFinishedWithServerHelloDone: true,
			},
		},
		shouldFail:         true,
		expectedError:      ":EXCESS_HANDSHAKE_DATA:",
		expectedLocalError: "remote error: unexpected message",
	})

	// Test that, in DTLS 1.2, key changes are not allowed when there are
	// buffered messages. Do this sending all messages in reverse, so that later
	// ones are buffered, and leaving Finished unencrypted.
	testCases = append(testCases, testCase{
		protocol: dtls,
		testType: serverTest,
		name:     "KeyChangeWithBufferedMessages-DTLS",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
					next = slices.Clone(next)
					slices.Reverse(next)
					for i := range next {
						next[i].Epoch = 0
					}
					c.WriteFlight(next)
				},
			},
		},
		shouldFail:    true,
		expectedError: ":EXCESS_HANDSHAKE_DATA:",
	})

	// Test synchronization between encryption changes and the handshake in
	// TLS 1.3, where ChangeCipherSpec is implicit.
	testCases = append(testCases, testCase{
		name: "PartialEncryptedExtensionsWithServerHello",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				PartialEncryptedExtensionsWithServerHello: true,
			},
		},
		shouldFail:    true,
		expectedError: ":EXCESS_HANDSHAKE_DATA:",
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "PartialClientFinishedWithClientHello",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				PartialClientFinishedWithClientHello: true,
			},
		},
		shouldFail:    true,
		expectedError: ":EXCESS_HANDSHAKE_DATA:",
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "PartialClientFinishedWithSecondClientHello",
		config: Config{
			MaxVersion: VersionTLS13,
			// Trigger a curve-based HelloRetryRequest.
			DefaultCurves: []CurveID{},
			Bugs: ProtocolBugs{
				PartialClientFinishedWithSecondClientHello: true,
			},
		},
		shouldFail:    true,
		expectedError: ":EXCESS_HANDSHAKE_DATA:",
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "PartialEndOfEarlyDataWithClientHello",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				PartialEndOfEarlyDataWithClientHello: true,
			},
		},
		resumeSession: true,
		earlyData:     true,
		shouldFail:    true,
		expectedError: ":EXCESS_HANDSHAKE_DATA:",
	})

	// Test that early ChangeCipherSpecs are handled correctly.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyChangeCipherSpec-server-1",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				EarlyChangeCipherSpec: 1,
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_RECORD:",
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyChangeCipherSpec-server-2",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				EarlyChangeCipherSpec: 2,
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_RECORD:",
	})
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "StrayChangeCipherSpec",
		config: Config{
			// TODO(davidben): Once DTLS 1.3 exists, test
			// that stray ChangeCipherSpec messages are
			// rejected.
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
					c.WriteFragments([]DTLSFragment{{IsChangeCipherSpec: true, Data: []byte{1}}})
					c.WriteFlight(next)
				},
			},
		},
	})

	// Test that the contents of ChangeCipherSpec are checked.
	testCases = append(testCases, testCase{
		name: "BadChangeCipherSpec-1",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				BadChangeCipherSpec: []byte{2},
			},
		},
		shouldFail:    true,
		expectedError: ":BAD_CHANGE_CIPHER_SPEC:",
	})
	testCases = append(testCases, testCase{
		name: "BadChangeCipherSpec-2",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				BadChangeCipherSpec: []byte{1, 1},
			},
		},
		shouldFail:    true,
		expectedError: ":BAD_CHANGE_CIPHER_SPEC:",
	})
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "BadChangeCipherSpec-DTLS-1",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				BadChangeCipherSpec: []byte{2},
			},
		},
		shouldFail:    true,
		expectedError: ":BAD_CHANGE_CIPHER_SPEC:",
	})
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "BadChangeCipherSpec-DTLS-2",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				BadChangeCipherSpec: []byte{1, 1},
			},
		},
		shouldFail:    true,
		expectedError: ":BAD_CHANGE_CIPHER_SPEC:",
	})
}

// addEndOfFlightTests adds tests where the runner adds extra data in the final
// record of each handshake flight. Depending on the implementation strategy,
// this data may be carried over to the next flight (assuming no key change) or
// may be rejected. To avoid differences with split handshakes and generally
// reject misbehavior, BoringSSL treats this as an error. When possible, these
// tests pull the extra data from the subsequent flight to distinguish the data
// being carried over from a general syntax error.
//
// These tests are similar to tests in |addChangeCipherSpecTests| that send
// extra data at key changes. Not all key changes are at the end of a flight and
// not all flights end at a key change.
func addEndOfFlightTests() {
	// TLS 1.3 client handshakes.
	//
	// Data following the second TLS 1.3 ClientHello is covered by
	// PartialClientFinishedWithClientHello,
	// PartialClientFinishedWithSecondClientHello, and
	// PartialEndOfEarlyDataWithClientHello in |addChangeCipherSpecTests|.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "PartialSecondClientHelloAfterFirst",
		config: Config{
			MaxVersion: VersionTLS13,
			// Trigger a curve-based HelloRetryRequest.
			DefaultCurves: []CurveID{},
			Bugs: ProtocolBugs{
				PartialSecondClientHelloAfterFirst: true,
			},
		},
		shouldFail:         true,
		expectedError:      ":EXCESS_HANDSHAKE_DATA:",
		expectedLocalError: "remote error: unexpected message",
	})

	// TLS 1.3 server handshakes.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "PartialServerHelloWithHelloRetryRequest",
		config: Config{
			MaxVersion: VersionTLS13,
			// P-384 requires HelloRetryRequest in BoringSSL.
			CurvePreferences: []CurveID{CurveP384},
			Bugs: ProtocolBugs{
				PartialServerHelloWithHelloRetryRequest: true,
			},
		},
		shouldFail:         true,
		expectedError:      ":EXCESS_HANDSHAKE_DATA:",
		expectedLocalError: "remote error: unexpected message",
	})

	// TLS 1.2 client handshakes.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "PartialClientKeyExchangeWithClientHello",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				PartialClientKeyExchangeWithClientHello: true,
			},
		},
		shouldFail:         true,
		expectedError:      ":EXCESS_HANDSHAKE_DATA:",
		expectedLocalError: "remote error: unexpected message",
	})

	// TLS 1.2 server handshakes.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "PartialNewSessionTicketWithServerHelloDone",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				PartialNewSessionTicketWithServerHelloDone: true,
			},
		},
		shouldFail:         true,
		expectedError:      ":EXCESS_HANDSHAKE_DATA:",
		expectedLocalError: "remote error: unexpected message",
	})

	for _, vers := range tlsVersions {
		for _, testType := range []testType{clientTest, serverTest} {
			suffix := "-Client"
			if testType == serverTest {
				suffix = "-Server"
			}
			suffix += "-" + vers.name

			testCases = append(testCases, testCase{
				testType: testType,
				name:     "TrailingDataWithFinished" + suffix,
				config: Config{
					MaxVersion: vers.version,
					Bugs: ProtocolBugs{
						TrailingDataWithFinished: true,
					},
				},
				shouldFail:         true,
				expectedError:      ":EXCESS_HANDSHAKE_DATA:",
				expectedLocalError: "remote error: unexpected message",
			})
			testCases = append(testCases, testCase{
				testType: testType,
				name:     "TrailingDataWithFinished-Resume" + suffix,
				config: Config{
					MaxVersion: vers.version,
				},
				resumeConfig: &Config{
					MaxVersion: vers.version,
					Bugs: ProtocolBugs{
						TrailingDataWithFinished: true,
					},
				},
				resumeSession:      true,
				shouldFail:         true,
				expectedError:      ":EXCESS_HANDSHAKE_DATA:",
				expectedLocalError: "remote error: unexpected message",
			})
		}
	}
}

type perMessageTest struct {
	messageType uint8
	test        testCase
}

// makePerMessageTests returns a series of test templates which cover each
// message in the TLS handshake. These may be used with bugs like
// WrongMessageType to fully test a per-message bug.
func makePerMessageTests() []perMessageTest {
	var ret []perMessageTest
	// The following tests are limited to TLS 1.2, so QUIC is not tested.
	for _, protocol := range []protocol{tls, dtls} {
		suffix := "-" + protocol.String()

		ret = append(ret, perMessageTest{
			messageType: typeClientHello,
			test: testCase{
				protocol: protocol,
				testType: serverTest,
				name:     "ClientHello" + suffix,
				config: Config{
					MaxVersion: VersionTLS12,
				},
			},
		})

		if protocol == dtls {
			ret = append(ret, perMessageTest{
				messageType: typeHelloVerifyRequest,
				test: testCase{
					protocol: protocol,
					name:     "HelloVerifyRequest" + suffix,
					config: Config{
						MaxVersion: VersionTLS12,
					},
				},
			})
		}

		ret = append(ret, perMessageTest{
			messageType: typeServerHello,
			test: testCase{
				protocol: protocol,
				name:     "ServerHello" + suffix,
				config: Config{
					MaxVersion: VersionTLS12,
				},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeCertificate,
			test: testCase{
				protocol: protocol,
				name:     "ServerCertificate" + suffix,
				config: Config{
					MaxVersion: VersionTLS12,
				},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeCertificateStatus,
			test: testCase{
				protocol: protocol,
				name:     "CertificateStatus" + suffix,
				config: Config{
					MaxVersion: VersionTLS12,
					Credential: rsaCertificate.WithOCSP(testOCSPResponse),
				},
				flags: []string{"-enable-ocsp-stapling"},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeServerKeyExchange,
			test: testCase{
				protocol: protocol,
				name:     "ServerKeyExchange" + suffix,
				config: Config{
					MaxVersion:   VersionTLS12,
					CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
				},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeCertificateRequest,
			test: testCase{
				protocol: protocol,
				name:     "CertificateRequest" + suffix,
				config: Config{
					MaxVersion: VersionTLS12,
					ClientAuth: RequireAnyClientCert,
				},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeServerHelloDone,
			test: testCase{
				protocol: protocol,
				name:     "ServerHelloDone" + suffix,
				config: Config{
					MaxVersion: VersionTLS12,
				},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeCertificate,
			test: testCase{
				testType: serverTest,
				protocol: protocol,
				name:     "ClientCertificate" + suffix,
				config: Config{
					Credential: &rsaCertificate,
					MaxVersion: VersionTLS12,
				},
				flags: []string{"-require-any-client-certificate"},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeCertificateVerify,
			test: testCase{
				testType: serverTest,
				protocol: protocol,
				name:     "CertificateVerify" + suffix,
				config: Config{
					Credential: &rsaCertificate,
					MaxVersion: VersionTLS12,
				},
				flags: []string{"-require-any-client-certificate"},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeClientKeyExchange,
			test: testCase{
				testType: serverTest,
				protocol: protocol,
				name:     "ClientKeyExchange" + suffix,
				config: Config{
					MaxVersion: VersionTLS12,
				},
			},
		})

		if protocol != dtls {
			ret = append(ret, perMessageTest{
				messageType: typeNextProtocol,
				test: testCase{
					testType: serverTest,
					protocol: protocol,
					name:     "NextProtocol" + suffix,
					config: Config{
						MaxVersion: VersionTLS12,
						NextProtos: []string{"bar"},
					},
					flags: []string{"-advertise-npn", "\x03foo\x03bar\x03baz"},
				},
			})

			ret = append(ret, perMessageTest{
				messageType: typeChannelID,
				test: testCase{
					testType: serverTest,
					protocol: protocol,
					name:     "ChannelID" + suffix,
					config: Config{
						MaxVersion: VersionTLS12,
						ChannelID:  &channelIDKey,
					},
					flags: []string{
						"-expect-channel-id",
						base64FlagValue(channelIDBytes),
					},
				},
			})
		}

		ret = append(ret, perMessageTest{
			messageType: typeFinished,
			test: testCase{
				testType: serverTest,
				protocol: protocol,
				name:     "ClientFinished" + suffix,
				config: Config{
					MaxVersion: VersionTLS12,
				},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeNewSessionTicket,
			test: testCase{
				protocol: protocol,
				name:     "NewSessionTicket" + suffix,
				config: Config{
					MaxVersion: VersionTLS12,
				},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeFinished,
			test: testCase{
				protocol: protocol,
				name:     "ServerFinished" + suffix,
				config: Config{
					MaxVersion: VersionTLS12,
				},
			},
		})

	}

	for _, protocol := range []protocol{tls, quic, dtls} {
		suffix := "-" + protocol.String()
		ret = append(ret, perMessageTest{
			messageType: typeClientHello,
			test: testCase{
				testType: serverTest,
				protocol: protocol,
				name:     "TLS13-ClientHello" + suffix,
				config: Config{
					MaxVersion: VersionTLS13,
				},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeServerHello,
			test: testCase{
				name:     "TLS13-ServerHello" + suffix,
				protocol: protocol,
				config: Config{
					MaxVersion: VersionTLS13,
				},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeEncryptedExtensions,
			test: testCase{
				name:     "TLS13-EncryptedExtensions" + suffix,
				protocol: protocol,
				config: Config{
					MaxVersion: VersionTLS13,
				},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeCertificateRequest,
			test: testCase{
				name:     "TLS13-CertificateRequest" + suffix,
				protocol: protocol,
				config: Config{
					MaxVersion: VersionTLS13,
					ClientAuth: RequireAnyClientCert,
				},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeCertificate,
			test: testCase{
				name:     "TLS13-ServerCertificate" + suffix,
				protocol: protocol,
				config: Config{
					MaxVersion: VersionTLS13,
				},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeCertificateVerify,
			test: testCase{
				name:     "TLS13-ServerCertificateVerify" + suffix,
				protocol: protocol,
				config: Config{
					MaxVersion: VersionTLS13,
				},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeFinished,
			test: testCase{
				name:     "TLS13-ServerFinished" + suffix,
				protocol: protocol,
				config: Config{
					MaxVersion: VersionTLS13,
				},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeCertificate,
			test: testCase{
				testType: serverTest,
				protocol: protocol,
				name:     "TLS13-ClientCertificate" + suffix,
				config: Config{
					Credential: &rsaCertificate,
					MaxVersion: VersionTLS13,
				},
				flags: []string{"-require-any-client-certificate"},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeCertificateVerify,
			test: testCase{
				testType: serverTest,
				protocol: protocol,
				name:     "TLS13-ClientCertificateVerify" + suffix,
				config: Config{
					Credential: &rsaCertificate,
					MaxVersion: VersionTLS13,
				},
				flags: []string{"-require-any-client-certificate"},
			},
		})

		ret = append(ret, perMessageTest{
			messageType: typeFinished,
			test: testCase{
				testType: serverTest,
				protocol: protocol,
				name:     "TLS13-ClientFinished" + suffix,
				config: Config{
					MaxVersion: VersionTLS13,
				},
			},
		})

		// Only TLS uses EndOfEarlyData.
		if protocol == tls {
			ret = append(ret, perMessageTest{
				messageType: typeEndOfEarlyData,
				test: testCase{
					testType: serverTest,
					protocol: protocol,
					name:     "TLS13-EndOfEarlyData" + suffix,
					config: Config{
						MaxVersion: VersionTLS13,
					},
					resumeSession: true,
					earlyData:     true,
				},
			})
		}
	}

	return ret
}

func addWrongMessageTypeTests() {
	for _, t := range makePerMessageTests() {
		t.test.name = "WrongMessageType-" + t.test.name
		if t.test.resumeConfig != nil {
			t.test.resumeConfig.Bugs.SendWrongMessageType = t.messageType
		} else {
			t.test.config.Bugs.SendWrongMessageType = t.messageType
		}
		t.test.shouldFail = true
		t.test.expectedError = ":UNEXPECTED_MESSAGE:"
		t.test.expectedLocalError = "remote error: unexpected message"

		if t.test.config.MaxVersion >= VersionTLS13 && t.messageType == typeServerHello {
			// In TLS 1.3, if the server believes it has sent ServerHello,
			// but the client cannot process it, the client will send an
			// unencrypted alert while the server expects encryption. This
			// decryption failure is reported differently for each protocol, so
			// leave it unchecked.
			t.test.expectedLocalError = ""
		}

		testCases = append(testCases, t.test)
	}
}

func addTrailingMessageDataTests() {
	for _, t := range makePerMessageTests() {
		t.test.name = "TrailingMessageData-" + t.test.name
		if t.test.resumeConfig != nil {
			t.test.resumeConfig.Bugs.SendTrailingMessageData = t.messageType
		} else {
			t.test.config.Bugs.SendTrailingMessageData = t.messageType
		}
		t.test.shouldFail = true
		t.test.expectedError = ":DECODE_ERROR:"
		t.test.expectedLocalError = "remote error: error decoding message"

		if t.test.config.MaxVersion >= VersionTLS13 && t.messageType == typeServerHello {
			// In TLS 1.3, if the server believes it has sent ServerHello,
			// but the client cannot process it, the client will send an
			// unencrypted alert while the server expects encryption. This
			// decryption failure is reported differently for each protocol, so
			// leave it unchecked.
			t.test.expectedLocalError = ""
		}

		if t.messageType == typeClientHello {
			// We have a different error for ClientHello parsing.
			t.test.expectedError = ":CLIENTHELLO_PARSE_FAILED:"
		}

		if t.messageType == typeFinished {
			// Bad Finished messages read as the verify data having
			// the wrong length.
			t.test.expectedError = ":DIGEST_CHECK_FAILED:"
			t.test.expectedLocalError = "remote error: error decrypting message"
		}

		testCases = append(testCases, t.test)
	}
}

func addTLS13HandshakeTests() {
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "NegotiatePSKResumption-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				NegotiatePSKResumption: true,
			},
		},
		resumeSession: true,
		shouldFail:    true,
		expectedError: ":MISSING_KEY_SHARE:",
	})

	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "MissingKeyShare-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				MissingKeyShare: true,
			},
		},
		shouldFail:    true,
		expectedError: ":MISSING_KEY_SHARE:",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "MissingKeyShare-Server-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				MissingKeyShare: true,
			},
		},
		shouldFail:    true,
		expectedError: ":MISSING_KEY_SHARE:",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "DuplicateKeyShares-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				DuplicateKeyShares: true,
			},
		},
		shouldFail:    true,
		expectedError: ":DUPLICATE_KEY_SHARE:",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SkipEarlyData-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendFakeEarlyDataLength: 4,
			},
		},
	})

	// Test that enabling TLS 1.3 does not interfere with TLS 1.2 session ID
	// resumption.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "ResumeTLS12SessionID-TLS13",
		config: Config{
			MaxVersion:             VersionTLS12,
			SessionTicketsDisabled: true,
		},
		flags:         []string{"-max-version", strconv.Itoa(VersionTLS13)},
		resumeSession: true,
	})

	// Test that the client correctly handles a TLS 1.3 ServerHello which echoes
	// a TLS 1.2 session ID.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "TLS12SessionID-TLS13",
		config: Config{
			MaxVersion:             VersionTLS12,
			SessionTicketsDisabled: true,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
		},
		resumeSession:        true,
		expectResumeRejected: true,
	})

	// Test that the server correctly echoes back session IDs of
	// various lengths. The first test additionally asserts that
	// BoringSSL always sends the ChangeCipherSpec messages for
	// compatibility mode, rather than negotiating it based on the
	// ClientHello.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EmptySessionID-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendClientHelloSessionID: []byte{},
			},
		},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "Server-ShortSessionID-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendClientHelloSessionID: make([]byte, 16),
			},
		},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "Server-FullSessionID-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendClientHelloSessionID: make([]byte, 32),
			},
		},
	})

	// The server should reject ClientHellos whose session IDs are too long.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "Server-TooLongSessionID-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendClientHelloSessionID: make([]byte, 33),
			},
		},
		shouldFail:         true,
		expectedError:      ":CLIENTHELLO_PARSE_FAILED:",
		expectedLocalError: "remote error: error decoding message",
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "Server-TooLongSessionID-TLS12",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SendClientHelloSessionID: make([]byte, 33),
			},
		},
		shouldFail:         true,
		expectedError:      ":CLIENTHELLO_PARSE_FAILED:",
		expectedLocalError: "remote error: error decoding message",
	})

	// Test that the client correctly accepts or rejects short session IDs from
	// the server. Our tests use 32 bytes by default, so the boundary condition
	// is already covered.
	testCases = append(testCases, testCase{
		name: "Client-ShortSessionID",
		config: Config{
			MaxVersion:             VersionTLS12,
			SessionTicketsDisabled: true,
			Bugs: ProtocolBugs{
				NewSessionIDLength: 1,
			},
		},
		resumeSession: true,
	})
	testCases = append(testCases, testCase{
		name: "Client-TooLongSessionID",
		config: Config{
			MaxVersion:             VersionTLS12,
			SessionTicketsDisabled: true,
			Bugs: ProtocolBugs{
				NewSessionIDLength: 33,
			},
		},
		shouldFail:         true,
		expectedError:      ":DECODE_ERROR:",
		expectedLocalError: "remote error: error decoding message",
	})

	// Test that the client sends a fake session ID in TLS 1.3. We cover both
	// normal and resumption handshakes to capture interactions with the
	// session resumption path.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "TLS13SessionID-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				ExpectClientHelloSessionID: true,
			},
		},
		resumeSession: true,
	})

	// Test that the client omits the fake session ID when the max version is TLS 1.2 and below.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "TLS12NoSessionID-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				ExpectNoSessionID: true,
			},
		},
		flags: []string{"-max-version", strconv.Itoa(VersionTLS12)},
	})

	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			MinVersion: VersionTLS13,
		},
		resumeSession: true,
		earlyData:     true,
		flags: []string{
			"-on-initial-expect-early-data-reason", "no_session_offered",
			"-on-resume-expect-early-data-reason", "accept",
		},
	})

	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-Reject-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				AlwaysRejectEarlyData: true,
			},
		},
		resumeSession:           true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			"-on-retry-expect-early-data-reason", "peer_declined",
		},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyData-Server-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			MinVersion: VersionTLS13,
		},
		messageCount:  2,
		resumeSession: true,
		earlyData:     true,
		flags: []string{
			"-on-initial-expect-early-data-reason", "no_session_offered",
			"-on-resume-expect-early-data-reason", "accept",
		},
	})

	// The above tests the most recent ticket. Additionally test that 0-RTT
	// works on the first ticket issued by the server.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyData-FirstTicket-Server-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			MinVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				UseFirstSessionTicket: true,
			},
		},
		messageCount:  2,
		resumeSession: true,
		earlyData:     true,
		flags: []string{
			"-on-resume-expect-early-data-reason", "accept",
		},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SkipEarlyData-OmitEarlyDataExtension-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendFakeEarlyDataLength: 4,
				OmitEarlyDataExtension:  true,
			},
		},
		shouldFail:    true,
		expectedError: ":DECRYPTION_FAILED_OR_BAD_RECORD_MAC:",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SkipEarlyData-OmitEarlyDataExtension-HelloRetryRequest-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			// Require a HelloRetryRequest for every curve.
			DefaultCurves: []CurveID{},
			Bugs: ProtocolBugs{
				SendFakeEarlyDataLength: 4,
				OmitEarlyDataExtension:  true,
			},
		},
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_RECORD:",
		expectedLocalError: "remote error: unexpected message",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SkipEarlyData-TooMuchData-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendFakeEarlyDataLength: 16384 + 1,
			},
		},
		shouldFail:    true,
		expectedError: ":TOO_MUCH_SKIPPED_EARLY_DATA:",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SkipEarlyData-Interleaved-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendFakeEarlyDataLength: 4,
				InterleaveEarlyData:     true,
			},
		},
		shouldFail:    true,
		expectedError: ":DECRYPTION_FAILED_OR_BAD_RECORD_MAC:",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SkipEarlyData-EarlyDataInTLS12-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendFakeEarlyDataLength: 4,
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_RECORD:",
		flags:         []string{"-max-version", strconv.Itoa(VersionTLS12)},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SkipEarlyData-HRR-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendFakeEarlyDataLength: 4,
			},
			DefaultCurves: []CurveID{},
		},
		// Though the session is not resumed and we send HelloRetryRequest,
		// early data being disabled takes priority as the reject reason.
		flags: []string{"-expect-early-data-reason", "disabled"},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SkipEarlyData-HRR-Interleaved-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendFakeEarlyDataLength: 4,
				InterleaveEarlyData:     true,
			},
			DefaultCurves: []CurveID{},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_RECORD:",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SkipEarlyData-HRR-TooMuchData-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendFakeEarlyDataLength: 16384 + 1,
			},
			DefaultCurves: []CurveID{},
		},
		shouldFail:    true,
		expectedError: ":TOO_MUCH_SKIPPED_EARLY_DATA:",
	})

	// Test that skipping early data looking for cleartext correctly
	// processes an alert record.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SkipEarlyData-HRR-FatalAlert-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendEarlyAlert:          true,
				SendFakeEarlyDataLength: 4,
			},
			DefaultCurves: []CurveID{},
		},
		shouldFail:    true,
		expectedError: ":SSLV3_ALERT_HANDSHAKE_FAILURE:",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SkipEarlyData-SecondClientHelloEarlyData-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendEarlyDataOnSecondClientHello: true,
			},
			DefaultCurves: []CurveID{},
		},
		shouldFail:         true,
		expectedLocalError: "remote error: bad record MAC",
	})

	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EmptyEncryptedExtensions-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				EmptyEncryptedExtensions: true,
			},
		},
		shouldFail:         true,
		expectedLocalError: "remote error: error decoding message",
	})

	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EncryptedExtensionsWithKeyShare-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				EncryptedExtensionsWithKeyShare: true,
			},
		},
		shouldFail:         true,
		expectedLocalError: "remote error: unsupported extension",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SendHelloRetryRequest-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			// Require a HelloRetryRequest for every curve.
			DefaultCurves:    []CurveID{},
			CurvePreferences: []CurveID{CurveX25519},
		},
		expectations: connectionExpectations{
			curveID: CurveX25519,
		},
		flags: []string{"-expect-hrr"},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SendHelloRetryRequest-2-TLS13",
		config: Config{
			MaxVersion:       VersionTLS13,
			DefaultCurves:    []CurveID{CurveP384},
			CurvePreferences: []CurveID{CurveX25519, CurveP384},
		},
		// Although the ClientHello did not predict our preferred curve,
		// we always select it whether it is predicted or not.
		expectations: connectionExpectations{
			curveID: CurveX25519,
		},
		flags: []string{"-expect-hrr"},
	})

	testCases = append(testCases, testCase{
		name: "UnknownCurve-HelloRetryRequest-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			// P-384 requires HelloRetryRequest in BoringSSL.
			CurvePreferences: []CurveID{CurveP384},
			Bugs: ProtocolBugs{
				SendHelloRetryRequestCurve: bogusCurve,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_CURVE:",
	})

	testCases = append(testCases, testCase{
		name: "HelloRetryRequest-CipherChange-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			// P-384 requires HelloRetryRequest in BoringSSL.
			CurvePreferences: []CurveID{CurveP384},
			Bugs: ProtocolBugs{
				SendCipherSuite:                  TLS_AES_128_GCM_SHA256,
				SendHelloRetryRequestCipherSuite: TLS_CHACHA20_POLY1305_SHA256,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_CIPHER_RETURNED:",
	})

	// Test that the client does not offer a PSK in the second ClientHello if the
	// HelloRetryRequest is incompatible with it.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "HelloRetryRequest-NonResumableCipher-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			CipherSuites: []uint16{
				TLS_AES_128_GCM_SHA256,
			},
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			// P-384 requires HelloRetryRequest in BoringSSL.
			CurvePreferences: []CurveID{CurveP384},
			Bugs: ProtocolBugs{
				ExpectNoTLS13PSKAfterHRR: true,
			},
			CipherSuites: []uint16{
				TLS_AES_256_GCM_SHA384,
			},
		},
		resumeSession:        true,
		expectResumeRejected: true,
	})

	testCases = append(testCases, testCase{
		name: "DisabledCurve-HelloRetryRequest-TLS13",
		config: Config{
			MaxVersion:       VersionTLS13,
			CurvePreferences: []CurveID{CurveP256},
			Bugs: ProtocolBugs{
				IgnorePeerCurvePreferences: true,
			},
		},
		flags:         []string{"-curves", strconv.Itoa(int(CurveP384))},
		shouldFail:    true,
		expectedError: ":WRONG_CURVE:",
	})

	testCases = append(testCases, testCase{
		name: "UnnecessaryHelloRetryRequest-TLS13",
		config: Config{
			MaxVersion:       VersionTLS13,
			CurvePreferences: []CurveID{CurveX25519},
			Bugs: ProtocolBugs{
				SendHelloRetryRequestCurve: CurveX25519,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_CURVE:",
	})

	testCases = append(testCases, testCase{
		name: "SecondHelloRetryRequest-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			// P-384 requires HelloRetryRequest in BoringSSL.
			CurvePreferences: []CurveID{CurveP384},
			Bugs: ProtocolBugs{
				SecondHelloRetryRequest: true,
			},
		},
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_MESSAGE:",
		expectedLocalError: "remote error: unexpected message",
	})

	testCases = append(testCases, testCase{
		name: "HelloRetryRequest-Empty-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				AlwaysSendHelloRetryRequest: true,
			},
		},
		shouldFail:         true,
		expectedError:      ":EMPTY_HELLO_RETRY_REQUEST:",
		expectedLocalError: "remote error: illegal parameter",
	})

	testCases = append(testCases, testCase{
		name: "HelloRetryRequest-DuplicateCurve-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			// P-384 requires a HelloRetryRequest against BoringSSL's default
			// configuration. Assert this ExpectMissingKeyShare.
			CurvePreferences: []CurveID{CurveP384},
			Bugs: ProtocolBugs{
				ExpectMissingKeyShare:                true,
				DuplicateHelloRetryRequestExtensions: true,
			},
		},
		shouldFail:         true,
		expectedError:      ":DUPLICATE_EXTENSION:",
		expectedLocalError: "remote error: illegal parameter",
	})

	testCases = append(testCases, testCase{
		name: "HelloRetryRequest-Cookie-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendHelloRetryRequestCookie: []byte("cookie"),
			},
		},
	})

	testCases = append(testCases, testCase{
		name: "HelloRetryRequest-DuplicateCookie-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendHelloRetryRequestCookie:          []byte("cookie"),
				DuplicateHelloRetryRequestExtensions: true,
			},
		},
		shouldFail:         true,
		expectedError:      ":DUPLICATE_EXTENSION:",
		expectedLocalError: "remote error: illegal parameter",
	})

	testCases = append(testCases, testCase{
		name: "HelloRetryRequest-EmptyCookie-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendHelloRetryRequestCookie: []byte{},
			},
		},
		shouldFail:    true,
		expectedError: ":DECODE_ERROR:",
	})

	testCases = append(testCases, testCase{
		name: "HelloRetryRequest-Cookie-Curve-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			// P-384 requires HelloRetryRequest in BoringSSL.
			CurvePreferences: []CurveID{CurveP384},
			Bugs: ProtocolBugs{
				SendHelloRetryRequestCookie: []byte("cookie"),
				ExpectMissingKeyShare:       true,
			},
		},
	})

	testCases = append(testCases, testCase{
		name: "HelloRetryRequest-Unknown-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				CustomHelloRetryRequestExtension: "extension",
			},
		},
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_EXTENSION:",
		expectedLocalError: "remote error: unsupported extension",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SecondClientHelloMissingKeyShare-TLS13",
		config: Config{
			MaxVersion:    VersionTLS13,
			DefaultCurves: []CurveID{},
			Bugs: ProtocolBugs{
				SecondClientHelloMissingKeyShare: true,
			},
		},
		shouldFail:    true,
		expectedError: ":MISSING_KEY_SHARE:",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SecondClientHelloWrongCurve-TLS13",
		config: Config{
			MaxVersion:    VersionTLS13,
			DefaultCurves: []CurveID{},
			Bugs: ProtocolBugs{
				MisinterpretHelloRetryRequestCurve: CurveP521,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_CURVE:",
	})

	testCases = append(testCases, testCase{
		name: "HelloRetryRequestVersionMismatch-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			// P-384 requires HelloRetryRequest in BoringSSL.
			CurvePreferences: []CurveID{CurveP384},
			Bugs: ProtocolBugs{
				SendServerHelloVersion: 0x0305,
			},
		},
		shouldFail:    true,
		expectedError: ":DECODE_ERROR:",
	})

	testCases = append(testCases, testCase{
		name: "HelloRetryRequestCurveMismatch-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			// P-384 requires HelloRetryRequest in BoringSSL.
			CurvePreferences: []CurveID{CurveP384},
			Bugs: ProtocolBugs{
				// Send P-384 (correct) in the HelloRetryRequest.
				SendHelloRetryRequestCurve: CurveP384,
				// But send P-256 in the ServerHello.
				SendCurve: CurveP256,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_CURVE:",
	})

	// Test the server selecting a curve that requires a HelloRetryRequest
	// without sending it.
	testCases = append(testCases, testCase{
		name: "SkipHelloRetryRequest-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			// P-384 requires HelloRetryRequest in BoringSSL.
			CurvePreferences: []CurveID{CurveP384},
			Bugs: ProtocolBugs{
				SkipHelloRetryRequest: true,
			},
		},
		shouldFail:    true,
		expectedError: ":WRONG_CURVE:",
	})

	testCases = append(testCases, testCase{
		name: "SecondServerHelloNoVersion-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			// P-384 requires HelloRetryRequest in BoringSSL.
			CurvePreferences: []CurveID{CurveP384},
			Bugs: ProtocolBugs{
				OmitServerSupportedVersionExtension: true,
			},
		},
		shouldFail:    true,
		expectedError: ":SECOND_SERVERHELLO_VERSION_MISMATCH:",
	})
	testCases = append(testCases, testCase{
		name: "SecondServerHelloWrongVersion-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			// P-384 requires HelloRetryRequest in BoringSSL.
			CurvePreferences: []CurveID{CurveP384},
			Bugs: ProtocolBugs{
				SendServerSupportedVersionExtension: 0x1234,
			},
		},
		shouldFail:    true,
		expectedError: ":SECOND_SERVERHELLO_VERSION_MISMATCH:",
	})

	testCases = append(testCases, testCase{
		name: "RequestContextInHandshake-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			MinVersion: VersionTLS13,
			ClientAuth: RequireAnyClientCert,
			Bugs: ProtocolBugs{
				SendRequestContext: []byte("request context"),
			},
		},
		shimCertificate: &rsaCertificate,
		shouldFail:      true,
		expectedError:   ":DECODE_ERROR:",
	})

	testCases = append(testCases, testCase{
		name: "UnknownExtensionInCertificateRequest-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			MinVersion: VersionTLS13,
			ClientAuth: RequireAnyClientCert,
			Bugs: ProtocolBugs{
				SendCustomCertificateRequest: 0x1212,
			},
		},
		shimCertificate: &rsaCertificate,
	})

	testCases = append(testCases, testCase{
		name: "MissingSignatureAlgorithmsInCertificateRequest-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			MinVersion: VersionTLS13,
			ClientAuth: RequireAnyClientCert,
			Bugs: ProtocolBugs{
				OmitCertificateRequestAlgorithms: true,
			},
		},
		shimCertificate: &rsaCertificate,
		shouldFail:      true,
		expectedError:   ":DECODE_ERROR:",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "TrailingKeyShareData-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				TrailingKeyShareData: true,
			},
		},
		shouldFail:    true,
		expectedError: ":DECODE_ERROR:",
	})

	testCases = append(testCases, testCase{
		name: "AlwaysSelectPSKIdentity-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				AlwaysSelectPSKIdentity: true,
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_EXTENSION:",
	})

	testCases = append(testCases, testCase{
		name: "InvalidPSKIdentity-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SelectPSKIdentityOnResume: 1,
			},
		},
		resumeSession: true,
		shouldFail:    true,
		expectedError: ":PSK_IDENTITY_NOT_FOUND:",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ExtraPSKIdentity-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				ExtraPSKIdentity:   true,
				SendExtraPSKBinder: true,
			},
		},
		resumeSession: true,
	})

	// Test that unknown NewSessionTicket extensions are tolerated.
	testCases = append(testCases, testCase{
		name: "CustomTicketExtension-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				CustomTicketExtension: "1234",
			},
		},
	})

	// Test the client handles 0-RTT being rejected by a full handshake
	// and correctly reports a certificate change.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-RejectTicket-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Credential: &rsaCertificate,
		},
		resumeConfig: &Config{
			MaxVersion:             VersionTLS13,
			Credential:             &ecdsaP256Certificate,
			SessionTicketsDisabled: true,
		},
		resumeSession:           true,
		expectResumeRejected:    true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			"-on-retry-expect-early-data-reason", "session_not_resumed",
			// Test the peer certificate is reported correctly in each of the
			// three logical connections.
			"-on-initial-expect-peer-cert-file", rsaCertificate.ChainPath,
			"-on-resume-expect-peer-cert-file", rsaCertificate.ChainPath,
			"-on-retry-expect-peer-cert-file", ecdsaP256Certificate.ChainPath,
			// Session tickets are disabled, so the runner will not send a ticket.
			"-on-retry-expect-no-session",
		},
	})

	// Test the server rejects 0-RTT if it does not recognize the ticket.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyData-RejectTicket-Server-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			MinVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				// Corrupt the ticket.
				FilterTicket: func(in []byte) ([]byte, error) {
					in[len(in)-1] ^= 1
					return in, nil
				},
			},
		},
		messageCount:            2,
		resumeSession:           true,
		expectResumeRejected:    true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			"-on-resume-expect-early-data-reason", "session_not_resumed",
		},
	})

	// Test the client handles 0-RTT being rejected via a HelloRetryRequest.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-HRR-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendHelloRetryRequestCookie: []byte{1, 2, 3, 4},
			},
		},
		resumeSession:           true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			"-on-retry-expect-early-data-reason", "hello_retry_request",
		},
	})

	// Test the server rejects 0-RTT if it needs to send a HelloRetryRequest.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyData-HRR-Server-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			MinVersion: VersionTLS13,
			// Require a HelloRetryRequest for every curve.
			DefaultCurves: []CurveID{},
		},
		messageCount:            2,
		resumeSession:           true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			"-on-resume-expect-early-data-reason", "hello_retry_request",
		},
	})

	// Test the client handles a 0-RTT reject from both ticket rejection and
	// HelloRetryRequest.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-HRR-RejectTicket-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Credential: &rsaCertificate,
		},
		resumeConfig: &Config{
			MaxVersion:             VersionTLS13,
			Credential:             &ecdsaP256Certificate,
			SessionTicketsDisabled: true,
			Bugs: ProtocolBugs{
				SendHelloRetryRequestCookie: []byte{1, 2, 3, 4},
			},
		},
		resumeSession:           true,
		expectResumeRejected:    true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			// The client sees HelloRetryRequest before the resumption result,
			// though neither value is inherently preferable.
			"-on-retry-expect-early-data-reason", "hello_retry_request",
			// Test the peer certificate is reported correctly in each of the
			// three logical connections.
			"-on-initial-expect-peer-cert-file", rsaCertificate.ChainPath,
			"-on-resume-expect-peer-cert-file", rsaCertificate.ChainPath,
			"-on-retry-expect-peer-cert-file", ecdsaP256Certificate.ChainPath,
			// Session tickets are disabled, so the runner will not send a ticket.
			"-on-retry-expect-no-session",
		},
	})

	// Test the server rejects 0-RTT if it needs to send a HelloRetryRequest.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyData-HRR-RejectTicket-Server-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			MinVersion: VersionTLS13,
			// Require a HelloRetryRequest for every curve.
			DefaultCurves: []CurveID{},
			Bugs: ProtocolBugs{
				// Corrupt the ticket.
				FilterTicket: func(in []byte) ([]byte, error) {
					in[len(in)-1] ^= 1
					return in, nil
				},
			},
		},
		messageCount:            2,
		resumeSession:           true,
		expectResumeRejected:    true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			// The server sees the missed resumption before HelloRetryRequest,
			// though neither value is inherently preferable.
			"-on-resume-expect-early-data-reason", "session_not_resumed",
		},
	})

	// The client must check the server does not send the early_data
	// extension while rejecting the session.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyDataWithoutResume-Client-TLS13",
		config: Config{
			MaxVersion:       VersionTLS13,
			MaxEarlyDataSize: 16384,
		},
		resumeConfig: &Config{
			MaxVersion:             VersionTLS13,
			SessionTicketsDisabled: true,
			Bugs: ProtocolBugs{
				SendEarlyDataExtension: true,
			},
		},
		resumeSession: true,
		earlyData:     true,
		shouldFail:    true,
		expectedError: ":UNEXPECTED_EXTENSION:",
	})

	// The client must fail with a dedicated error code if the server
	// responds with TLS 1.2 when offering 0-RTT.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyDataVersionDowngrade-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS12,
		},
		resumeSession: true,
		earlyData:     true,
		shouldFail:    true,
		expectedError: ":WRONG_VERSION_ON_EARLY_DATA:",
	})

	// Same as above, but the server also sends a warning alert before the
	// ServerHello. Although the shim predicts TLS 1.3 for 0-RTT, it should
	// still interpret data before ServerHello in a TLS-1.2-compatible way.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyDataVersionDowngrade-Client-TLS13-WarningAlert",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SendSNIWarningAlert: true,
			},
		},
		resumeSession: true,
		earlyData:     true,
		shouldFail:    true,
		expectedError: ":WRONG_VERSION_ON_EARLY_DATA:",
	})

	// Test that the client rejects an (unsolicited) early_data extension if
	// the server sent an HRR.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "ServerAcceptsEarlyDataOnHRR-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendHelloRetryRequestCookie: []byte{1, 2, 3, 4},
				SendEarlyDataExtension:      true,
			},
		},
		resumeSession: true,
		earlyData:     true,
		// The client will first process an early data reject from the HRR.
		expectEarlyDataRejected: true,
		shouldFail:              true,
		expectedError:           ":UNEXPECTED_EXTENSION:",
	})

	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "SkipChangeCipherSpec-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SkipChangeCipherSpec: true,
			},
		},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "SkipChangeCipherSpec-Server-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SkipChangeCipherSpec: true,
			},
		},
	})

	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "TooManyChangeCipherSpec-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendExtraChangeCipherSpec: 33,
			},
		},
		shouldFail:    true,
		expectedError: ":TOO_MANY_EMPTY_FRAGMENTS:",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "TooManyChangeCipherSpec-Server-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendExtraChangeCipherSpec: 33,
			},
		},
		shouldFail:    true,
		expectedError: ":TOO_MANY_EMPTY_FRAGMENTS:",
	})

	testCases = append(testCases, testCase{
		name: "SendPostHandshakeChangeCipherSpec-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendPostHandshakeChangeCipherSpec: true,
			},
		},
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_RECORD:",
		expectedLocalError: "remote error: unexpected message",
	})

	fooString := "foo"
	barString := "bar"

	// Test that the client reports the correct ALPN after a 0-RTT reject
	// that changed it.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-ALPNMismatch-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				ALPNProtocol: &fooString,
			},
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				ALPNProtocol: &barString,
			},
		},
		resumeSession:           true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			"-advertise-alpn", "\x03foo\x03bar",
			// The client does not learn ALPN was the cause.
			"-on-retry-expect-early-data-reason", "peer_declined",
			// In the 0-RTT state, we surface the predicted ALPN. After
			// processing the reject, we surface the real one.
			"-on-initial-expect-alpn", "foo",
			"-on-resume-expect-alpn", "foo",
			"-on-retry-expect-alpn", "bar",
		},
	})

	// Test that the client reports the correct ALPN after a 0-RTT reject if
	// ALPN was omitted from the first connection.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-ALPNOmitted1-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			NextProtos: []string{"foo"},
		},
		resumeSession:           true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			"-advertise-alpn", "\x03foo\x03bar",
			// The client does not learn ALPN was the cause.
			"-on-retry-expect-early-data-reason", "peer_declined",
			// In the 0-RTT state, we surface the predicted ALPN. After
			// processing the reject, we surface the real one.
			"-on-initial-expect-alpn", "",
			"-on-resume-expect-alpn", "",
			"-on-retry-expect-alpn", "foo",
		},
	})

	// Test that the client reports the correct ALPN after a 0-RTT reject if
	// ALPN was omitted from the second connection.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-ALPNOmitted2-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			NextProtos: []string{"foo"},
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
		},
		resumeSession:           true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			"-advertise-alpn", "\x03foo\x03bar",
			// The client does not learn ALPN was the cause.
			"-on-retry-expect-early-data-reason", "peer_declined",
			// In the 0-RTT state, we surface the predicted ALPN. After
			// processing the reject, we surface the real one.
			"-on-initial-expect-alpn", "foo",
			"-on-resume-expect-alpn", "foo",
			"-on-retry-expect-alpn", "",
		},
	})

	// Test that the client enforces ALPN match on 0-RTT accept.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-BadALPNMismatch-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				ALPNProtocol: &fooString,
			},
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				AlwaysAcceptEarlyData: true,
				ALPNProtocol:          &barString,
			},
		},
		resumeSession: true,
		earlyData:     true,
		flags: []string{
			"-advertise-alpn", "\x03foo\x03bar",
			"-on-initial-expect-alpn", "foo",
			"-on-resume-expect-alpn", "foo",
			"-on-retry-expect-alpn", "bar",
		},
		shouldFail:         true,
		expectedError:      ":ALPN_MISMATCH_ON_EARLY_DATA:",
		expectedLocalError: "remote error: illegal parameter",
	})

	// Test that the client does not offer early data if it is incompatible
	// with ALPN preferences.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-ALPNPreferenceChanged-TLS13",
		config: Config{
			MaxVersion:       VersionTLS13,
			MaxEarlyDataSize: 16384,
			NextProtos:       []string{"foo", "bar"},
		},
		resumeSession: true,
		flags: []string{
			"-enable-early-data",
			"-expect-ticket-supports-early-data",
			"-expect-no-offer-early-data",
			// Offer different ALPN values in the initial and resumption.
			"-on-initial-advertise-alpn", "\x03foo",
			"-on-initial-expect-alpn", "foo",
			"-on-resume-advertise-alpn", "\x03bar",
			"-on-resume-expect-alpn", "bar",
			// The ALPN mismatch comes from the client, so it reports it as the
			// reason.
			"-on-resume-expect-early-data-reason", "alpn_mismatch",
		},
	})

	// Test that the client does not offer 0-RTT to servers which never
	// advertise it.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-NonZeroRTTSession-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeSession: true,
		flags: []string{
			"-enable-early-data",
			"-on-resume-expect-no-offer-early-data",
			// The client declines to offer 0-RTT because of the session.
			"-on-resume-expect-early-data-reason", "unsupported_for_session",
		},
	})

	// Test that the server correctly rejects 0-RTT when the previous
	// session did not allow early data on resumption.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyData-NonZeroRTTSession-Server-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendEarlyData:           [][]byte{{1, 2, 3, 4}},
				ExpectEarlyDataAccepted: false,
			},
		},
		resumeSession: true,
		// This test configures early data manually instead of the earlyData
		// option, to customize the -enable-early-data flag.
		flags: []string{
			"-on-resume-enable-early-data",
			"-expect-reject-early-data",
			// The server rejects 0-RTT because of the session.
			"-on-resume-expect-early-data-reason", "unsupported_for_session",
		},
	})

	// Test that we reject early data where ALPN is omitted from the first
	// connection, but negotiated in the second.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyData-ALPNOmitted1-Server-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			NextProtos: []string{},
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			NextProtos: []string{"foo"},
		},
		resumeSession:           true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			"-on-initial-select-alpn", "",
			"-on-resume-select-alpn", "foo",
			"-on-resume-expect-early-data-reason", "alpn_mismatch",
		},
	})

	// Test that we reject early data where ALPN is omitted from the second
	// connection, but negotiated in the first.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyData-ALPNOmitted2-Server-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			NextProtos: []string{"foo"},
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			NextProtos: []string{},
		},
		resumeSession:           true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			"-on-initial-select-alpn", "foo",
			"-on-resume-select-alpn", "",
			"-on-resume-expect-early-data-reason", "alpn_mismatch",
		},
	})

	// Test that we reject early data with mismatched ALPN.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyData-ALPNMismatch-Server-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			NextProtos: []string{"foo"},
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			NextProtos: []string{"bar"},
		},
		resumeSession:           true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			"-on-initial-select-alpn", "foo",
			"-on-resume-select-alpn", "bar",
			"-on-resume-expect-early-data-reason", "alpn_mismatch",
		},
	})

	// Test that the client offering 0-RTT and Channel ID forbids the server
	// from accepting both.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyDataChannelID-AcceptBoth-Client-TLS13",
		config: Config{
			MaxVersion:       VersionTLS13,
			RequestChannelID: true,
		},
		resumeSession: true,
		earlyData:     true,
		expectations: connectionExpectations{
			channelID: true,
		},
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_EXTENSION_ON_EARLY_DATA:",
		expectedLocalError: "remote error: illegal parameter",
		flags: []string{
			"-send-channel-id", channelIDKeyPath,
		},
	})

	// Test that the client offering Channel ID and 0-RTT allows the server
	// to decline 0-RTT.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyDataChannelID-AcceptChannelID-Client-TLS13",
		config: Config{
			MaxVersion:       VersionTLS13,
			RequestChannelID: true,
			Bugs: ProtocolBugs{
				AlwaysRejectEarlyData: true,
			},
		},
		resumeSession:           true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		expectations: connectionExpectations{
			channelID: true,
		},
		flags: []string{
			"-send-channel-id", channelIDKeyPath,
			// The client never learns the reason was Channel ID.
			"-on-retry-expect-early-data-reason", "peer_declined",
		},
	})

	// Test that the client offering Channel ID and 0-RTT allows the server
	// to decline Channel ID.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyDataChannelID-AcceptEarlyData-Client-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeSession: true,
		earlyData:     true,
		flags: []string{
			"-send-channel-id", channelIDKeyPath,
		},
	})

	// Test that the server supporting Channel ID and 0-RTT declines 0-RTT
	// if it would negotiate Channel ID.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyDataChannelID-OfferBoth-Server-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			ChannelID:  &channelIDKey,
		},
		resumeSession:           true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		expectations: connectionExpectations{
			channelID: true,
		},
		flags: []string{
			"-expect-channel-id",
			base64FlagValue(channelIDBytes),
			"-on-resume-expect-early-data-reason", "channel_id",
		},
	})

	// Test that the server supporting Channel ID and 0-RTT accepts 0-RTT
	// if not offered Channel ID.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyDataChannelID-OfferEarlyData-Server-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeSession: true,
		earlyData:     true,
		expectations: connectionExpectations{
			channelID: false,
		},
		flags: []string{
			"-enable-channel-id",
			"-on-resume-expect-early-data-reason", "accept",
		},
	})

	// Test that the server errors on 0-RTT streams without EndOfEarlyData.
	// The subsequent records should fail to decrypt.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyData-SkipEndOfEarlyData-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SkipEndOfEarlyData: true,
			},
		},
		resumeSession:      true,
		earlyData:          true,
		shouldFail:         true,
		expectedLocalError: "remote error: bad record MAC",
		expectedError:      ":BAD_DECRYPT:",
	})

	// Test that EndOfEarlyData is rejected in QUIC. Since we leave application
	// data to the QUIC implementation, we never accept any data at all in
	// the 0-RTT epoch, so the error is that the encryption level is rejected
	// outright.
	//
	// TODO(crbug.com/381113363): Test this for DTLS 1.3 as well.
	testCases = append(testCases, testCase{
		protocol: quic,
		testType: serverTest,
		name:     "EarlyData-UnexpectedEndOfEarlyData-QUIC",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendEndOfEarlyDataInQUICAndDTLS: true,
			},
		},
		resumeSession: true,
		earlyData:     true,
		shouldFail:    true,
		expectedError: ":WRONG_ENCRYPTION_LEVEL_RECEIVED:",
	})

	// Test that the server errors on 0-RTT streams with a stray handshake
	// message in them.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyData-UnexpectedHandshake-Server-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				SendStrayEarlyHandshake: true,
			},
		},
		resumeSession:      true,
		earlyData:          true,
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_MESSAGE:",
		expectedLocalError: "remote error: unexpected message",
	})

	// Test that the client reports TLS 1.3 as the version while sending
	// early data.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-Client-VersionAPI-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeSession: true,
		earlyData:     true,
		flags: []string{
			"-expect-version", strconv.Itoa(VersionTLS13),
			// EMS and RI are always reported as supported when we report
			// TLS 1.3.
			"-expect-extended-master-secret",
			"-expect-secure-renegotiation",
		},
	})

	// Test that client and server both notice handshake errors after data
	// has started flowing.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-Client-BadFinished-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				BadFinished: true,
			},
		},
		resumeSession:      true,
		earlyData:          true,
		shouldFail:         true,
		expectedError:      ":DIGEST_CHECK_FAILED:",
		expectedLocalError: "remote error: error decrypting message",
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyData-Server-BadFinished-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				BadFinished: true,
			},
		},
		resumeSession:      true,
		earlyData:          true,
		shouldFail:         true,
		expectedError:      ":DIGEST_CHECK_FAILED:",
		expectedLocalError: "remote error: error decrypting message",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "Server-NonEmptyEndOfEarlyData-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		resumeConfig: &Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				NonEmptyEndOfEarlyData: true,
			},
		},
		resumeSession: true,
		earlyData:     true,
		shouldFail:    true,
		expectedError: ":DECODE_ERROR:",
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ServerSkipCertificateVerify-TLS13",
		config: Config{
			MinVersion: VersionTLS13,
			MaxVersion: VersionTLS13,
			Credential: &rsaChainCertificate,
			Bugs: ProtocolBugs{
				SkipCertificateVerify: true,
			},
		},
		expectations: connectionExpectations{
			peerCertificate: &rsaCertificate,
		},
		shimCertificate: &rsaCertificate,
		flags: []string{
			"-require-any-client-certificate",
		},
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_MESSAGE:",
		expectedLocalError: "remote error: unexpected message",
	})
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "ClientSkipCertificateVerify-TLS13",
		config: Config{
			MinVersion: VersionTLS13,
			MaxVersion: VersionTLS13,
			Credential: &rsaChainCertificate,
			Bugs: ProtocolBugs{
				SkipCertificateVerify: true,
			},
		},
		expectations: connectionExpectations{
			peerCertificate: &rsaCertificate,
		},
		shimCertificate:    &rsaCertificate,
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_MESSAGE:",
		expectedLocalError: "remote error: unexpected message",
	})

	// PSK/resumption handshakes should not accept CertificateRequest or
	// Certificate messages.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "CertificateInResumption-TLS13",
		config: Config{
			MinVersion: VersionTLS13,
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				AlwaysSendCertificate: true,
			},
		},
		resumeSession:      true,
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_MESSAGE:",
		expectedLocalError: "remote error: unexpected message",
	})
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "CertificateRequestInResumption-TLS13",
		config: Config{
			MinVersion: VersionTLS13,
			MaxVersion: VersionTLS13,
			ClientAuth: RequireAnyClientCert,
			Bugs: ProtocolBugs{
				AlwaysSendCertificateRequest: true,
			},
		},
		shimCertificate:    &rsaCertificate,
		resumeSession:      true,
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_MESSAGE:",
		expectedLocalError: "remote error: unexpected message",
	})

	// If the client or server has 0-RTT enabled but disabled TLS 1.3, it should
	// report a reason of protocol_version.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyDataEnabled-Client-MaxTLS12",
		expectations: connectionExpectations{
			version: VersionTLS12,
		},
		flags: []string{
			"-enable-early-data",
			"-max-version", strconv.Itoa(VersionTLS12),
			"-expect-early-data-reason", "protocol_version",
		},
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyDataEnabled-Server-MaxTLS12",
		expectations: connectionExpectations{
			version: VersionTLS12,
		},
		flags: []string{
			"-enable-early-data",
			"-max-version", strconv.Itoa(VersionTLS12),
			"-expect-early-data-reason", "protocol_version",
		},
	})

	// The server additionally reports protocol_version if it enabled TLS 1.3,
	// but the peer negotiated TLS 1.2. (The corresponding situation does not
	// exist on the client because negotiating TLS 1.2 with a 0-RTT ClientHello
	// is a fatal error.)
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "EarlyDataEnabled-Server-NegotiateTLS12",
		config: Config{
			MaxVersion: VersionTLS12,
		},
		expectations: connectionExpectations{
			version: VersionTLS12,
		},
		flags: []string{
			"-enable-early-data",
			"-expect-early-data-reason", "protocol_version",
		},
	})

	// On 0-RTT reject, the server may end up negotiating a cipher suite with a
	// different PRF hash. Test that the client handles this correctly.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-Reject0RTT-DifferentPRF-Client",
		config: Config{
			MaxVersion:   VersionTLS13,
			CipherSuites: []uint16{TLS_AES_128_GCM_SHA256},
		},
		resumeConfig: &Config{
			MaxVersion:   VersionTLS13,
			CipherSuites: []uint16{TLS_AES_256_GCM_SHA384},
		},
		resumeSession:           true,
		expectResumeRejected:    true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			"-on-initial-expect-cipher", strconv.Itoa(int(TLS_AES_128_GCM_SHA256)),
			// The client initially reports the old cipher suite while sending
			// early data. After processing the 0-RTT reject, it reports the
			// true cipher suite.
			"-on-resume-expect-cipher", strconv.Itoa(int(TLS_AES_128_GCM_SHA256)),
			"-on-retry-expect-cipher", strconv.Itoa(int(TLS_AES_256_GCM_SHA384)),
		},
	})
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-Reject0RTT-DifferentPRF-HRR-Client",
		config: Config{
			MaxVersion:   VersionTLS13,
			CipherSuites: []uint16{TLS_AES_128_GCM_SHA256},
		},
		resumeConfig: &Config{
			MaxVersion:   VersionTLS13,
			CipherSuites: []uint16{TLS_AES_256_GCM_SHA384},
			// P-384 requires a HelloRetryRequest against BoringSSL's default
			// configuration. Assert this with ExpectMissingKeyShare.
			CurvePreferences: []CurveID{CurveP384},
			Bugs: ProtocolBugs{
				ExpectMissingKeyShare: true,
			},
		},
		resumeSession:           true,
		expectResumeRejected:    true,
		earlyData:               true,
		expectEarlyDataRejected: true,
		flags: []string{
			"-on-initial-expect-cipher", strconv.Itoa(int(TLS_AES_128_GCM_SHA256)),
			// The client initially reports the old cipher suite while sending
			// early data. After processing the 0-RTT reject, it reports the
			// true cipher suite.
			"-on-resume-expect-cipher", strconv.Itoa(int(TLS_AES_128_GCM_SHA256)),
			"-on-retry-expect-cipher", strconv.Itoa(int(TLS_AES_256_GCM_SHA384)),
		},
	})

	// Test that the client enforces cipher suite match on 0-RTT accept.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-CipherMismatch-Client-TLS13",
		config: Config{
			MaxVersion:   VersionTLS13,
			CipherSuites: []uint16{TLS_AES_128_GCM_SHA256},
		},
		resumeConfig: &Config{
			MaxVersion:   VersionTLS13,
			CipherSuites: []uint16{TLS_CHACHA20_POLY1305_SHA256},
			Bugs: ProtocolBugs{
				AlwaysAcceptEarlyData: true,
			},
		},
		resumeSession:      true,
		earlyData:          true,
		shouldFail:         true,
		expectedError:      ":CIPHER_MISMATCH_ON_EARLY_DATA:",
		expectedLocalError: "remote error: illegal parameter",
	})

	// Test that the client can write early data when it has received a partial
	// ServerHello..Finished flight. See https://crbug.com/1208784. Note the
	// EncryptedExtensions test assumes EncryptedExtensions and Finished are in
	// separate records, i.e. that PackHandshakeFlight is disabled.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-WriteAfterServerHello",
		config: Config{
			MinVersion: VersionTLS13,
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				// Write the server response before expecting early data.
				ExpectEarlyData:     [][]byte{},
				ExpectLateEarlyData: [][]byte{[]byte(shimInitialWrite)},
			},
		},
		resumeSession: true,
		earlyData:     true,
		flags: []string{
			"-async",
			"-on-resume-early-write-after-message",
			strconv.Itoa(int(typeServerHello)),
		},
	})
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "EarlyData-WriteAfterEncryptedExtensions",
		config: Config{
			MinVersion: VersionTLS13,
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				// Write the server response before expecting early data.
				ExpectEarlyData:     [][]byte{},
				ExpectLateEarlyData: [][]byte{[]byte(shimInitialWrite)},
			},
		},
		resumeSession: true,
		earlyData:     true,
		flags: []string{
			"-async",
			"-on-resume-early-write-after-message",
			strconv.Itoa(int(typeEncryptedExtensions)),
		},
	})
}

func addTLS13CipherPreferenceTests() {
	// Test that client preference is honored if the shim has AES hardware
	// and ChaCha20-Poly1305 is preferred otherwise.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "TLS13-CipherPreference-Server-ChaCha20-AES",
		config: Config{
			MaxVersion: VersionTLS13,
			CipherSuites: []uint16{
				TLS_CHACHA20_POLY1305_SHA256,
				TLS_AES_128_GCM_SHA256,
			},
			CurvePreferences: []CurveID{CurveX25519},
		},
		flags: []string{
			"-expect-cipher-aes", strconv.Itoa(int(TLS_CHACHA20_POLY1305_SHA256)),
			"-expect-cipher-no-aes", strconv.Itoa(int(TLS_CHACHA20_POLY1305_SHA256)),
		},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "TLS13-CipherPreference-Server-AES-ChaCha20",
		config: Config{
			MaxVersion: VersionTLS13,
			CipherSuites: []uint16{
				TLS_AES_128_GCM_SHA256,
				TLS_CHACHA20_POLY1305_SHA256,
			},
			CurvePreferences: []CurveID{CurveX25519},
		},
		flags: []string{
			"-expect-cipher-aes", strconv.Itoa(int(TLS_AES_128_GCM_SHA256)),
			"-expect-cipher-no-aes", strconv.Itoa(int(TLS_CHACHA20_POLY1305_SHA256)),
		},
	})

	// Test that the client orders ChaCha20-Poly1305 and AES-GCM based on
	// whether it has AES hardware.
	testCases = append(testCases, testCase{
		name: "TLS13-CipherPreference-Client",
		config: Config{
			MaxVersion: VersionTLS13,
			// Use the client cipher order. (This is the default but
			// is listed to be explicit.)
			PreferServerCipherSuites: false,
		},
		flags: []string{
			"-expect-cipher-aes", strconv.Itoa(int(TLS_AES_128_GCM_SHA256)),
			"-expect-cipher-no-aes", strconv.Itoa(int(TLS_CHACHA20_POLY1305_SHA256)),
		},
	})
}

func addPeekTests() {
	// Test SSL_peek works, including on empty records.
	testCases = append(testCases, testCase{
		name:             "Peek-Basic",
		sendEmptyRecords: 1,
		flags:            []string{"-peek-then-read"},
	})

	// Test SSL_peek can drive the initial handshake.
	testCases = append(testCases, testCase{
		name: "Peek-ImplicitHandshake",
		flags: []string{
			"-peek-then-read",
			"-implicit-handshake",
		},
	})

	// Test SSL_peek can discover and drive a renegotiation.
	testCases = append(testCases, testCase{
		name: "Peek-Renegotiate",
		config: Config{
			MaxVersion: VersionTLS12,
		},
		renegotiate: 1,
		flags: []string{
			"-peek-then-read",
			"-renegotiate-freely",
			"-expect-total-renegotiations", "1",
		},
	})

	// Test SSL_peek can discover a close_notify.
	testCases = append(testCases, testCase{
		name: "Peek-Shutdown",
		config: Config{
			Bugs: ProtocolBugs{
				ExpectCloseNotify: true,
			},
		},
		flags: []string{
			"-peek-then-read",
			"-check-close-notify",
		},
	})

	// Test SSL_peek can discover an alert.
	testCases = append(testCases, testCase{
		name: "Peek-Alert",
		config: Config{
			Bugs: ProtocolBugs{
				SendSpuriousAlert: alertRecordOverflow,
			},
		},
		flags:         []string{"-peek-then-read"},
		shouldFail:    true,
		expectedError: ":TLSV1_ALERT_RECORD_OVERFLOW:",
	})

	// Test SSL_peek can handle KeyUpdate.
	testCases = append(testCases, testCase{
		name: "Peek-KeyUpdate",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		sendKeyUpdates:   1,
		keyUpdateRequest: keyUpdateNotRequested,
		flags:            []string{"-peek-then-read"},
	})
}

func addRecordVersionTests() {
	for _, ver := range tlsVersions {
		// Test that the record version is enforced.
		testCases = append(testCases, testCase{
			name: "CheckRecordVersion-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Bugs: ProtocolBugs{
					SendRecordVersion: 0x03ff,
				},
			},
			shouldFail:    true,
			expectedError: ":WRONG_VERSION_NUMBER:",
		})

		// Test that the ClientHello may use any record version, for
		// compatibility reasons.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "LooseInitialRecordVersion-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Bugs: ProtocolBugs{
					SendInitialRecordVersion: 0x03ff,
				},
			},
		})

		// Test that garbage ClientHello record versions are rejected.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "GarbageInitialRecordVersion-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Bugs: ProtocolBugs{
					SendInitialRecordVersion: 0xffff,
				},
			},
			shouldFail:    true,
			expectedError: ":WRONG_VERSION_NUMBER:",
		})
	}
}

func addCertificateTests() {
	for _, ver := range tlsVersions {
		// Test that a certificate chain with intermediate may be sent
		// and received as both client and server.
		testCases = append(testCases, testCase{
			testType: clientTest,
			name:     "SendReceiveIntermediate-Client-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Credential: &rsaChainCertificate,
				ClientAuth: RequireAnyClientCert,
			},
			expectations: connectionExpectations{
				peerCertificate: &rsaChainCertificate,
			},
			shimCertificate: &rsaChainCertificate,
			flags: []string{
				"-expect-peer-cert-file", rsaChainCertificate.ChainPath,
			},
		})

		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "SendReceiveIntermediate-Server-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Credential: &rsaChainCertificate,
			},
			expectations: connectionExpectations{
				peerCertificate: &rsaChainCertificate,
			},
			shimCertificate: &rsaChainCertificate,
			flags: []string{
				"-require-any-client-certificate",
				"-expect-peer-cert-file", rsaChainCertificate.ChainPath,
			},
		})

		// Test that garbage leaf certificates are properly rejected.
		testCases = append(testCases, testCase{
			testType: clientTest,
			name:     "GarbageCertificate-Client-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Credential: &garbageCertificate,
			},
			shouldFail:         true,
			expectedError:      ":CANNOT_PARSE_LEAF_CERT:",
			expectedLocalError: "remote error: error decoding message",
		})

		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "GarbageCertificate-Server-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Credential: &garbageCertificate,
			},
			flags:              []string{"-require-any-client-certificate"},
			shouldFail:         true,
			expectedError:      ":CANNOT_PARSE_LEAF_CERT:",
			expectedLocalError: "remote error: error decoding message",
		})
	}
}

func addRetainOnlySHA256ClientCertTests() {
	for _, ver := range tlsVersions {
		// Test that enabling
		// SSL_CTX_set_retain_only_sha256_of_client_certs without
		// actually requesting a client certificate is a no-op.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "RetainOnlySHA256-NoCert-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
			},
			flags: []string{
				"-on-initial-retain-only-sha256-client-cert",
				"-on-resume-retain-only-sha256-client-cert",
			},
			resumeSession: true,
		})

		// Test that when retaining only a SHA-256 certificate is
		// enabled, the hash appears as expected.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "RetainOnlySHA256-Cert-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Credential: &rsaCertificate,
			},
			flags: []string{
				"-verify-peer",
				"-on-initial-retain-only-sha256-client-cert",
				"-on-resume-retain-only-sha256-client-cert",
				"-on-initial-expect-sha256-client-cert",
				"-on-resume-expect-sha256-client-cert",
			},
			resumeSession: true,
		})

		// Test that when the config changes from on to off, a
		// resumption is rejected because the server now wants the full
		// certificate chain.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "RetainOnlySHA256-OnOff-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Credential: &rsaCertificate,
			},
			flags: []string{
				"-verify-peer",
				"-on-initial-retain-only-sha256-client-cert",
				"-on-initial-expect-sha256-client-cert",
			},
			resumeSession:        true,
			expectResumeRejected: true,
		})

		// Test that when the config changes from off to on, a
		// resumption is rejected because the server now wants just the
		// hash.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "RetainOnlySHA256-OffOn-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Credential: &rsaCertificate,
			},
			flags: []string{
				"-verify-peer",
				"-on-resume-retain-only-sha256-client-cert",
				"-on-resume-expect-sha256-client-cert",
			},
			resumeSession:        true,
			expectResumeRejected: true,
		})
	}
}

func addECDSAKeyUsageTests() {
	serialNumberLimit := new(big.Int).Lsh(big.NewInt(1), 128)
	serialNumber, err := rand.Int(rand.Reader, serialNumberLimit)
	if err != nil {
		panic(err)
	}

	template := &x509.Certificate{
		SerialNumber: serialNumber,
		Subject: pkix.Name{
			Organization: []string{"Acme Co"},
		},
		NotBefore: time.Now(),
		NotAfter:  time.Now(),

		// An ECC certificate with only the keyAgreement key usgae may
		// be used with ECDH, but not ECDSA.
		KeyUsage:              x509.KeyUsageKeyAgreement,
		ExtKeyUsage:           []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
		BasicConstraintsValid: true,
	}

	cert := generateSingleCertChain(template, &ecdsaP256Key)

	for _, ver := range tlsVersions {
		if ver.version < VersionTLS12 {
			continue
		}

		testCases = append(testCases, testCase{
			testType: clientTest,
			name:     "ECDSAKeyUsage-Client-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Credential: &cert,
			},
			shouldFail:    true,
			expectedError: ":KEY_USAGE_BIT_INCORRECT:",
		})

		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "ECDSAKeyUsage-Server-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Credential: &cert,
			},
			flags:         []string{"-require-any-client-certificate"},
			shouldFail:    true,
			expectedError: ":KEY_USAGE_BIT_INCORRECT:",
		})
	}
}

func addRSAKeyUsageTests() {
	priv := rsaCertificate.PrivateKey.(*rsa.PrivateKey)

	serialNumberLimit := new(big.Int).Lsh(big.NewInt(1), 128)
	serialNumber, err := rand.Int(rand.Reader, serialNumberLimit)
	if err != nil {
		panic(err)
	}

	dsTemplate := x509.Certificate{
		SerialNumber: serialNumber,
		Subject: pkix.Name{
			Organization: []string{"Acme Co"},
		},
		NotBefore: time.Now(),
		NotAfter:  time.Now(),

		KeyUsage:              x509.KeyUsageDigitalSignature,
		BasicConstraintsValid: true,
	}

	encTemplate := x509.Certificate{
		SerialNumber: serialNumber,
		Subject: pkix.Name{
			Organization: []string{"Acme Co"},
		},
		NotBefore: time.Now(),
		NotAfter:  time.Now(),

		KeyUsage:              x509.KeyUsageKeyEncipherment,
		BasicConstraintsValid: true,
	}

	dsCert := generateSingleCertChain(&dsTemplate, priv)

	encCert := generateSingleCertChain(&encTemplate, priv)

	dsSuites := []uint16{
		TLS_AES_128_GCM_SHA256,
		TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
		TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
	}
	encSuites := []uint16{
		TLS_RSA_WITH_AES_128_GCM_SHA256,
		TLS_RSA_WITH_AES_128_CBC_SHA,
	}

	for _, ver := range tlsVersions {
		testCases = append(testCases, testCase{
			testType: clientTest,
			name:     "RSAKeyUsage-Client-WantSignature-GotEncipherment-" + ver.name,
			config: Config{
				MinVersion:   ver.version,
				MaxVersion:   ver.version,
				Credential:   &encCert,
				CipherSuites: dsSuites,
			},
			shouldFail:    true,
			expectedError: ":KEY_USAGE_BIT_INCORRECT:",
		})

		testCases = append(testCases, testCase{
			testType: clientTest,
			name:     "RSAKeyUsage-Client-WantSignature-GotSignature-" + ver.name,
			config: Config{
				MinVersion:   ver.version,
				MaxVersion:   ver.version,
				Credential:   &dsCert,
				CipherSuites: dsSuites,
			},
		})

		// TLS 1.3 removes the encipherment suites.
		if ver.version < VersionTLS13 {
			testCases = append(testCases, testCase{
				testType: clientTest,
				name:     "RSAKeyUsage-Client-WantEncipherment-GotEncipherment" + ver.name,
				config: Config{
					MinVersion:   ver.version,
					MaxVersion:   ver.version,
					Credential:   &encCert,
					CipherSuites: encSuites,
				},
			})

			testCases = append(testCases, testCase{
				testType: clientTest,
				name:     "RSAKeyUsage-Client-WantEncipherment-GotSignature-" + ver.name,
				config: Config{
					MinVersion:   ver.version,
					MaxVersion:   ver.version,
					Credential:   &dsCert,
					CipherSuites: encSuites,
				},
				shouldFail:    true,
				expectedError: ":KEY_USAGE_BIT_INCORRECT:",
			})

			// In 1.2 and below, we should not enforce without the enforce-rsa-key-usage flag.
			testCases = append(testCases, testCase{
				testType: clientTest,
				name:     "RSAKeyUsage-Client-WantSignature-GotEncipherment-Unenforced-" + ver.name,
				config: Config{
					MinVersion:   ver.version,
					MaxVersion:   ver.version,
					Credential:   &dsCert,
					CipherSuites: encSuites,
				},
				flags: []string{"-expect-key-usage-invalid", "-ignore-rsa-key-usage"},
			})

			testCases = append(testCases, testCase{
				testType: clientTest,
				name:     "RSAKeyUsage-Client-WantEncipherment-GotSignature-Unenforced-" + ver.name,
				config: Config{
					MinVersion:   ver.version,
					MaxVersion:   ver.version,
					Credential:   &encCert,
					CipherSuites: dsSuites,
				},
				flags: []string{"-expect-key-usage-invalid", "-ignore-rsa-key-usage"},
			})
		}

		if ver.version >= VersionTLS13 {
			// In 1.3 and above, we enforce keyUsage even when disabled.
			testCases = append(testCases, testCase{
				testType: clientTest,
				name:     "RSAKeyUsage-Client-WantSignature-GotEncipherment-AlwaysEnforced-" + ver.name,
				config: Config{
					MinVersion:   ver.version,
					MaxVersion:   ver.version,
					Credential:   &encCert,
					CipherSuites: dsSuites,
				},
				flags:         []string{"-ignore-rsa-key-usage"},
				shouldFail:    true,
				expectedError: ":KEY_USAGE_BIT_INCORRECT:",
			})
		}

		// The server only uses signatures and always enforces it.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "RSAKeyUsage-Server-WantSignature-GotEncipherment-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Credential: &encCert,
			},
			shouldFail:    true,
			expectedError: ":KEY_USAGE_BIT_INCORRECT:",
			flags:         []string{"-require-any-client-certificate"},
		})

		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "RSAKeyUsage-Server-WantSignature-GotSignature-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Credential: &dsCert,
			},
			flags: []string{"-require-any-client-certificate"},
		})

	}
}

func addExtraHandshakeTests() {
	// An extra SSL_do_handshake is normally a no-op. These tests use -async
	// to ensure there is no transport I/O.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "ExtraHandshake-Client-TLS12",
		config: Config{
			MinVersion: VersionTLS12,
			MaxVersion: VersionTLS12,
		},
		flags: []string{
			"-async",
			"-no-op-extra-handshake",
		},
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ExtraHandshake-Server-TLS12",
		config: Config{
			MinVersion: VersionTLS12,
			MaxVersion: VersionTLS12,
		},
		flags: []string{
			"-async",
			"-no-op-extra-handshake",
		},
	})
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "ExtraHandshake-Client-TLS13",
		config: Config{
			MinVersion: VersionTLS13,
			MaxVersion: VersionTLS13,
		},
		flags: []string{
			"-async",
			"-no-op-extra-handshake",
		},
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ExtraHandshake-Server-TLS13",
		config: Config{
			MinVersion: VersionTLS13,
			MaxVersion: VersionTLS13,
		},
		flags: []string{
			"-async",
			"-no-op-extra-handshake",
		},
	})

	// An extra SSL_do_handshake is a no-op in server 0-RTT.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ExtraHandshake-Server-EarlyData-TLS13",
		config: Config{
			MaxVersion: VersionTLS13,
			MinVersion: VersionTLS13,
		},
		messageCount:  2,
		resumeSession: true,
		earlyData:     true,
		flags: []string{
			"-async",
			"-no-op-extra-handshake",
		},
	})

	// An extra SSL_do_handshake drives the handshake to completion in False
	// Start. We test this by handshaking twice and asserting the False
	// Start does not appear to happen. See AlertBeforeFalseStartTest for
	// how the test works.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "ExtraHandshake-FalseStart",
		config: Config{
			MaxVersion:   VersionTLS12,
			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			NextProtos:   []string{"foo"},
			Bugs: ProtocolBugs{
				ExpectFalseStart:          true,
				AlertBeforeFalseStartTest: alertAccessDenied,
			},
		},
		flags: []string{
			"-handshake-twice",
			"-false-start",
			"-advertise-alpn", "\x03foo",
			"-expect-alpn", "foo",
		},
		shimWritesFirst:    true,
		shouldFail:         true,
		expectedError:      ":TLSV1_ALERT_ACCESS_DENIED:",
		expectedLocalError: "tls: peer did not false start: EOF",
	})
}

// Test that omitted and empty extensions blocks are tolerated.
func addOmitExtensionsTests() {
	// Check the ExpectOmitExtensions setting works.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "ExpectOmitExtensions",
		config: Config{
			MinVersion: VersionTLS12,
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				ExpectOmitExtensions: true,
			},
		},
		shouldFail:         true,
		expectedLocalError: "tls: ServerHello did not omit extensions",
	})

	for _, ver := range tlsVersions {
		if ver.version > VersionTLS12 {
			continue
		}

		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "OmitExtensions-ClientHello-" + ver.name,
			config: Config{
				MinVersion:             ver.version,
				MaxVersion:             ver.version,
				SessionTicketsDisabled: true,
				Bugs: ProtocolBugs{
					OmitExtensions: true,
					// With no client extensions, the ServerHello must not have
					// extensions. It should then omit the extensions field.
					ExpectOmitExtensions: true,
				},
			},
		})

		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "EmptyExtensions-ClientHello-" + ver.name,
			config: Config{
				MinVersion:             ver.version,
				MaxVersion:             ver.version,
				SessionTicketsDisabled: true,
				Bugs: ProtocolBugs{
					EmptyExtensions: true,
					// With no client extensions, the ServerHello must not have
					// extensions. It should then omit the extensions field.
					ExpectOmitExtensions: true,
				},
			},
		})

		testCases = append(testCases, testCase{
			testType: clientTest,
			name:     "OmitExtensions-ServerHello-" + ver.name,
			config: Config{
				MinVersion:             ver.version,
				MaxVersion:             ver.version,
				SessionTicketsDisabled: true,
				Bugs: ProtocolBugs{
					OmitExtensions: true,
					// Disable all ServerHello extensions so
					// OmitExtensions works.
					NoExtendedMasterSecret:        true,
					NoRenegotiationInfo:           true,
					NoOCSPStapling:                true,
					NoSignedCertificateTimestamps: true,
				},
			},
		})

		testCases = append(testCases, testCase{
			testType: clientTest,
			name:     "EmptyExtensions-ServerHello-" + ver.name,
			config: Config{
				MinVersion:             ver.version,
				MaxVersion:             ver.version,
				SessionTicketsDisabled: true,
				Bugs: ProtocolBugs{
					EmptyExtensions: true,
					// Disable all ServerHello extensions so
					// EmptyExtensions works.
					NoExtendedMasterSecret:        true,
					NoRenegotiationInfo:           true,
					NoOCSPStapling:                true,
					NoSignedCertificateTimestamps: true,
				},
			},
		})
	}
}

const (
	shrinkingCompressionAlgID = 0xff01
	expandingCompressionAlgID = 0xff02
	randomCompressionAlgID    = 0xff03
)

var (
	// shrinkingPrefix is the first two bytes of a Certificate message.
	shrinkingPrefix = []byte{0, 0}
	// expandingPrefix is just some arbitrary byte string. This has to match the
	// value in the shim.
	expandingPrefix = []byte{1, 2, 3, 4}
)

var shrinkingCompression = CertCompressionAlg{
	Compress: func(uncompressed []byte) []byte {
		if !bytes.HasPrefix(uncompressed, shrinkingPrefix) {
			panic(fmt.Sprintf("cannot compress certificate message %x", uncompressed))
		}
		return uncompressed[len(shrinkingPrefix):]
	},
	Decompress: func(out []byte, compressed []byte) bool {
		if len(out) != len(shrinkingPrefix)+len(compressed) {
			return false
		}

		copy(out, shrinkingPrefix)
		copy(out[len(shrinkingPrefix):], compressed)
		return true
	},
}

var expandingCompression = CertCompressionAlg{
	Compress: func(uncompressed []byte) []byte {
		ret := make([]byte, 0, len(expandingPrefix)+len(uncompressed))
		ret = append(ret, expandingPrefix...)
		return append(ret, uncompressed...)
	},
	Decompress: func(out []byte, compressed []byte) bool {
		if !bytes.HasPrefix(compressed, expandingPrefix) {
			return false
		}
		copy(out, compressed[len(expandingPrefix):])
		return true
	},
}

var randomCompression = CertCompressionAlg{
	Compress: func(uncompressed []byte) []byte {
		ret := make([]byte, 1+len(uncompressed))
		if _, err := rand.Read(ret[:1]); err != nil {
			panic(err)
		}
		copy(ret[1:], uncompressed)
		return ret
	},
	Decompress: func(out []byte, compressed []byte) bool {
		if len(compressed) != 1+len(out) {
			return false
		}
		copy(out, compressed[1:])
		return true
	},
}

func addCertCompressionTests() {
	for _, ver := range tlsVersions {
		if ver.version < VersionTLS12 {
			continue
		}

		// Duplicate compression algorithms is an error, even if nothing is
		// configured.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "DuplicateCertCompressionExt-" + ver.name,
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Bugs: ProtocolBugs{
					DuplicateCompressedCertAlgs: true,
				},
			},
			shouldFail:    true,
			expectedError: ":ERROR_PARSING_EXTENSION:",
		})

		// With compression algorithms configured, an duplicate values should still
		// be an error.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "DuplicateCertCompressionExt2-" + ver.name,
			flags:    []string{"-install-cert-compression-algs"},
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				Bugs: ProtocolBugs{
					DuplicateCompressedCertAlgs: true,
				},
			},
			shouldFail:    true,
			expectedError: ":ERROR_PARSING_EXTENSION:",
		})

		if ver.version < VersionTLS13 {
			testCases = append(testCases, testCase{
				testType: serverTest,
				name:     "CertCompressionIgnoredBefore13-" + ver.name,
				flags:    []string{"-install-cert-compression-algs"},
				config: Config{
					MinVersion: ver.version,
					MaxVersion: ver.version,
					CertCompressionAlgs: map[uint16]CertCompressionAlg{
						expandingCompressionAlgID: expandingCompression,
					},
				},
			})

			continue
		}

		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "CertCompressionExpands-" + ver.name,
			flags:    []string{"-install-cert-compression-algs"},
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				CertCompressionAlgs: map[uint16]CertCompressionAlg{
					expandingCompressionAlgID: expandingCompression,
				},
				Bugs: ProtocolBugs{
					ExpectedCompressedCert: expandingCompressionAlgID,
				},
			},
		})

		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "CertCompressionShrinks-" + ver.name,
			flags:    []string{"-install-cert-compression-algs"},
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				CertCompressionAlgs: map[uint16]CertCompressionAlg{
					shrinkingCompressionAlgID: shrinkingCompression,
				},
				Bugs: ProtocolBugs{
					ExpectedCompressedCert: shrinkingCompressionAlgID,
				},
			},
		})

		// Test that the shim behaves consistently if the compression function
		// is non-deterministic. This is intended to model version differences
		// between the shim and handshaker with handshake hints, but it is also
		// useful in confirming we only call the callbacks once.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "CertCompressionRandom-" + ver.name,
			flags:    []string{"-install-cert-compression-algs"},
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				CertCompressionAlgs: map[uint16]CertCompressionAlg{
					randomCompressionAlgID: randomCompression,
				},
				Bugs: ProtocolBugs{
					ExpectedCompressedCert: randomCompressionAlgID,
				},
			},
		})

		// With both algorithms configured, the server should pick its most
		// preferable. (Which is expandingCompressionAlgID.)
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "CertCompressionPriority-" + ver.name,
			flags:    []string{"-install-cert-compression-algs"},
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				CertCompressionAlgs: map[uint16]CertCompressionAlg{
					shrinkingCompressionAlgID: shrinkingCompression,
					expandingCompressionAlgID: expandingCompression,
				},
				Bugs: ProtocolBugs{
					ExpectedCompressedCert: expandingCompressionAlgID,
				},
			},
		})

		// With no common algorithms configured, the server should decline
		// compression.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     "CertCompressionNoCommonAlgs-" + ver.name,
			flags:    []string{"-install-one-cert-compression-alg", strconv.Itoa(shrinkingCompressionAlgID)},
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				CertCompressionAlgs: map[uint16]CertCompressionAlg{
					expandingCompressionAlgID: expandingCompression,
				},
				Bugs: ProtocolBugs{
					ExpectUncompressedCert: true,
				},
			},
		})

		testCases = append(testCases, testCase{
			testType: clientTest,
			name:     "CertCompressionExpandsClient-" + ver.name,
			flags:    []string{"-install-cert-compression-algs"},
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				CertCompressionAlgs: map[uint16]CertCompressionAlg{
					expandingCompressionAlgID: expandingCompression,
				},
				Bugs: ProtocolBugs{
					ExpectedCompressedCert: expandingCompressionAlgID,
				},
			},
		})

		testCases = append(testCases, testCase{
			testType: clientTest,
			name:     "CertCompressionShrinksClient-" + ver.name,
			flags:    []string{"-install-cert-compression-algs"},
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				CertCompressionAlgs: map[uint16]CertCompressionAlg{
					shrinkingCompressionAlgID: shrinkingCompression,
				},
				Bugs: ProtocolBugs{
					ExpectedCompressedCert: shrinkingCompressionAlgID,
				},
			},
		})

		testCases = append(testCases, testCase{
			testType: clientTest,
			name:     "CertCompressionBadAlgIDClient-" + ver.name,
			flags:    []string{"-install-cert-compression-algs"},
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				CertCompressionAlgs: map[uint16]CertCompressionAlg{
					shrinkingCompressionAlgID: shrinkingCompression,
				},
				Bugs: ProtocolBugs{
					ExpectedCompressedCert:   shrinkingCompressionAlgID,
					SendCertCompressionAlgID: 1234,
				},
			},
			shouldFail:    true,
			expectedError: ":UNKNOWN_CERT_COMPRESSION_ALG:",
		})

		testCases = append(testCases, testCase{
			testType: clientTest,
			name:     "CertCompressionTooSmallClient-" + ver.name,
			flags:    []string{"-install-cert-compression-algs"},
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				CertCompressionAlgs: map[uint16]CertCompressionAlg{
					shrinkingCompressionAlgID: shrinkingCompression,
				},
				Bugs: ProtocolBugs{
					ExpectedCompressedCert:     shrinkingCompressionAlgID,
					SendCertUncompressedLength: 12,
				},
			},
			shouldFail:    true,
			expectedError: ":CERT_DECOMPRESSION_FAILED:",
		})

		testCases = append(testCases, testCase{
			testType: clientTest,
			name:     "CertCompressionTooLargeClient-" + ver.name,
			flags:    []string{"-install-cert-compression-algs"},
			config: Config{
				MinVersion: ver.version,
				MaxVersion: ver.version,
				CertCompressionAlgs: map[uint16]CertCompressionAlg{
					shrinkingCompressionAlgID: shrinkingCompression,
				},
				Bugs: ProtocolBugs{
					ExpectedCompressedCert:     shrinkingCompressionAlgID,
					SendCertUncompressedLength: 1 << 20,
				},
			},
			shouldFail:    true,
			expectedError: ":UNCOMPRESSED_CERT_TOO_LARGE:",
		})
	}
}

func addJDK11WorkaroundTests() {
	// Test the client treats the JDK 11 downgrade random like the usual one.
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "Client-RejectJDK11DowngradeRandom",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SendJDK11DowngradeRandom: true,
			},
		},
		shouldFail:         true,
		expectedError:      ":TLS13_DOWNGRADE:",
		expectedLocalError: "remote error: illegal parameter",
	})
	testCases = append(testCases, testCase{
		testType: clientTest,
		name:     "Client-AcceptJDK11DowngradeRandom",
		config: Config{
			MaxVersion: VersionTLS12,
			Bugs: ProtocolBugs{
				SendJDK11DowngradeRandom: true,
			},
		},
		flags: []string{"-max-version", strconv.Itoa(VersionTLS12)},
	})

	clientHelloTests := []struct {
		clientHello []byte
		isJDK11     bool
	}{
		{
			// A default JDK 11 ClientHello.
			decodeHexOrPanic("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"),
			true,
		},
		{
			// The above with supported_versions and
			// psk_key_exchange_modes in the wrong order.
			decodeHexOrPanic("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"),
			false,
		},
		{
			// The above with a padding extension added at the end.
			decodeHexOrPanic("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"),
			false,
		},
		{
			// A JDK 11 ClientHello offering a TLS 1.3 PSK.
			decodeHexOrPanic("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"),
			true,
		},
		{
			// A JDK 11 ClientHello offering a TLS 1.2 session.
			decodeHexOrPanic("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"),
			true,
		},
		{
			// A JDK 11 ClientHello with EMS disabled.
			decodeHexOrPanic("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"),
			true,
		},
		{
			// A JDK 11 ClientHello with OCSP stapling disabled.
			decodeHexOrPanic("0100019303038a50481dc85ee4f6581670821c50f2b3d34ac3251dc6e9b751bfd2521ab47ab02069a963c5486034c37ae0577ddb4c2db28cab592380ef8e4599d1305148712112005a13011302c02cc02bc030009dc02ec032009f00a3c02f009cc02dc031009e00a2c024c028003dc026c02a006b006ac00ac0140035c005c00f00390038c023c027003cc025c02900670040c009c013002fc004c00e0033003200ff010000f0000000080006000003736e69000a0020001e0017001800190009000a000b000c000d000e001601000101010201030104000b00020100000d002800260403050306030804080508060809080a080b04010501060104020303030103020203020102020032002800260403050306030804080508060809080a080b040105010601040203030301030202030201020200170000002b0009080304030303020301002d00020101003300470045001700410438a97824f842c549e3c339322d8b2dbaa85d10bd7bca9c969376cb0c60b1e929eb4d13db38dcb0082ad8c637b24f55466a9acbb0b63634c1f431ec8342cf720d"),
			true,
		},
		{
			// A JDK 11 ClientHello configured with a smaller set of
			// ciphers.
			decodeHexOrPanic("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"),
			true,
		},
		{
			// The above with TLS_CHACHA20_POLY1305_SHA256 added,
			// which JDK 11 does not support.
			decodeHexOrPanic("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"),
			false,
		},
		{
			// The above with X25519 added, which JDK 11 does not
			// support.
			decodeHexOrPanic("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"),
			false,
		},
		{
			// A JDK 11 ClientHello with ALPN protocols configured.
			decodeHexOrPanic("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"),
			true,
		},
	}
	for i, t := range clientHelloTests {
		expectedVersion := uint16(VersionTLS13)
		if t.isJDK11 {
			expectedVersion = VersionTLS12
		}

		// In each of these tests, we set DefaultCurves to P-256 to
		// match the test inputs. SendClientHelloWithFixes requires the
		// key_shares extension to match in type.

		// With the workaround enabled, we should negotiate TLS 1.2 on
		// JDK 11 ClientHellos.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     fmt.Sprintf("Server-JDK11-%d", i),
			config: Config{
				MaxVersion:    VersionTLS13,
				DefaultCurves: []CurveID{CurveP256},
				Bugs: ProtocolBugs{
					SendClientHelloWithFixes:   t.clientHello,
					ExpectJDK11DowngradeRandom: t.isJDK11,
				},
			},
			expectations: connectionExpectations{
				version: expectedVersion,
			},
			flags: []string{"-jdk11-workaround"},
		})

		// With the workaround disabled, we always negotiate TLS 1.3.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     fmt.Sprintf("Server-JDK11-NoWorkaround-%d", i),
			config: Config{
				MaxVersion:    VersionTLS13,
				DefaultCurves: []CurveID{CurveP256},
				Bugs: ProtocolBugs{
					SendClientHelloWithFixes:   t.clientHello,
					ExpectJDK11DowngradeRandom: false,
				},
			},
			expectations: connectionExpectations{
				version: VersionTLS13,
			},
		})

		// If the server does not support TLS 1.3, the workaround should
		// be a no-op. In particular, it should not send the downgrade
		// signal.
		testCases = append(testCases, testCase{
			testType: serverTest,
			name:     fmt.Sprintf("Server-JDK11-TLS12-%d", i),
			config: Config{
				MaxVersion:    VersionTLS13,
				DefaultCurves: []CurveID{CurveP256},
				Bugs: ProtocolBugs{
					SendClientHelloWithFixes:   t.clientHello,
					ExpectJDK11DowngradeRandom: false,
				},
			},
			expectations: connectionExpectations{
				version: VersionTLS12,
			},
			flags: []string{
				"-jdk11-workaround",
				"-max-version", strconv.Itoa(VersionTLS12),
			},
		})
	}
}

func addDelegatedCredentialTests() {
	p256DC := createDelegatedCredential(&rsaCertificate, delegatedCredentialConfig{
		dcAlgo: signatureECDSAWithP256AndSHA256,
		algo:   signatureRSAPSSWithSHA256,
	})
	p256DCFromECDSA := createDelegatedCredential(&ecdsaP256Certificate, delegatedCredentialConfig{
		dcAlgo: signatureECDSAWithP256AndSHA256,
		algo:   signatureECDSAWithP256AndSHA256,
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "DelegatedCredentials-NoClientSupport",
		config: Config{
			MinVersion: VersionTLS13,
			MaxVersion: VersionTLS13,
		},
		shimCredentials: []*Credential{p256DC, &rsaCertificate},
		flags:           []string{"-expect-selected-credential", "1"},
		expectations: connectionExpectations{
			peerCertificate: &rsaCertificate,
		},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "DelegatedCredentials-Basic",
		config: Config{
			MinVersion:                    VersionTLS13,
			MaxVersion:                    VersionTLS13,
			DelegatedCredentialAlgorithms: []signatureAlgorithm{signatureECDSAWithP256AndSHA256},
		},
		shimCredentials: []*Credential{p256DC, &rsaCertificate},
		flags:           []string{"-expect-selected-credential", "0"},
		expectations: connectionExpectations{
			peerCertificate: p256DC,
		},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "DelegatedCredentials-ExactAlgorithmMatch",
		config: Config{
			MinVersion: VersionTLS13,
			MaxVersion: VersionTLS13,
			// Test that the server doesn't mix up the two signature algorithm
			// fields. These options are a match because the signature_algorithms
			// extension matches against the signature on the delegated
			// credential, while the delegated_credential extension matches
			// against the signature made by the delegated credential.
			VerifySignatureAlgorithms:     []signatureAlgorithm{signatureRSAPSSWithSHA256},
			DelegatedCredentialAlgorithms: []signatureAlgorithm{signatureECDSAWithP256AndSHA256},
		},
		shimCredentials: []*Credential{p256DC, &rsaCertificate},
		flags:           []string{"-expect-selected-credential", "0"},
		expectations: connectionExpectations{
			peerCertificate: p256DC,
		},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "DelegatedCredentials-SigAlgoMissing",
		config: Config{
			MinVersion: VersionTLS13,
			MaxVersion: VersionTLS13,
			// If the client doesn't support the signature in the delegated credential,
			// the server should not use delegated credentials.
			VerifySignatureAlgorithms:     []signatureAlgorithm{signatureRSAPSSWithSHA384},
			DelegatedCredentialAlgorithms: []signatureAlgorithm{signatureECDSAWithP256AndSHA256},
		},
		shimCredentials: []*Credential{p256DC, &rsaCertificate},
		flags:           []string{"-expect-selected-credential", "1"},
		expectations: connectionExpectations{
			peerCertificate: &rsaCertificate,
		},
	})

	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "DelegatedCredentials-CertVerifySigAlgoMissing",
		config: Config{
			MinVersion: VersionTLS13,
			MaxVersion: VersionTLS13,
			// If the client doesn't support the delegated credential's
			// CertificateVerify algorithm, the server should not use delegated
			// credentials.
			VerifySignatureAlgorithms:     []signatureAlgorithm{signatureRSAPSSWithSHA256},
			DelegatedCredentialAlgorithms: []signatureAlgorithm{signatureECDSAWithP384AndSHA384},
		},
		shimCredentials: []*Credential{p256DC, &rsaCertificate},
		flags:           []string{"-expect-selected-credential", "1"},
		expectations: connectionExpectations{
			peerCertificate: &rsaCertificate,
		},
	})

	// Delegated credentials are not supported at TLS 1.2, even if the client
	// sends the extension.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "DelegatedCredentials-TLS12-Forbidden",
		config: Config{
			MinVersion:                    VersionTLS12,
			MaxVersion:                    VersionTLS12,
			DelegatedCredentialAlgorithms: []signatureAlgorithm{signatureECDSAWithP256AndSHA256},
		},
		shimCredentials: []*Credential{p256DC, &rsaCertificate},
		flags:           []string{"-expect-selected-credential", "1"},
		expectations: connectionExpectations{
			peerCertificate: &rsaCertificate,
		},
	})

	// Generate another delegated credential, so we can get the keys out of sync.
	dcWrongKey := createDelegatedCredential(&rsaCertificate, delegatedCredentialConfig{
		algo: signatureRSAPSSWithSHA256,
	})
	dcWrongKey.DelegatedCredential = p256DC.DelegatedCredential
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "DelegatedCredentials-KeyMismatch",
		// The handshake hints version of the test will, as a side effect, use a
		// custom private key. Custom private keys can't be checked for key
		// mismatches.
		skipHints:       true,
		shimCredentials: []*Credential{dcWrongKey},
		shouldFail:      true,
		expectedError:   ":KEY_VALUES_MISMATCH:",
	})

	// RSA delegated credentials should be rejected at configuration time.
	rsaDC := createDelegatedCredential(&rsaCertificate, delegatedCredentialConfig{
		algo:   signatureRSAPSSWithSHA256,
		dcAlgo: signatureRSAPSSWithSHA256,
	})
	testCases = append(testCases, testCase{
		testType:        serverTest,
		name:            "DelegatedCredentials-NoRSA",
		shimCredentials: []*Credential{rsaDC},
		shouldFail:      true,
		expectedError:   ":INVALID_SIGNATURE_ALGORITHM:",
	})

	// If configured with multiple delegated credentials, the server can cleanly
	// select the first one that works.
	p384DC := createDelegatedCredential(&rsaCertificate, delegatedCredentialConfig{
		dcAlgo: signatureECDSAWithP384AndSHA384,
		algo:   signatureRSAPSSWithSHA256,
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "DelegatedCredentials-Multiple",
		config: Config{
			DelegatedCredentialAlgorithms: []signatureAlgorithm{signatureECDSAWithP384AndSHA384},
		},
		shimCredentials: []*Credential{p256DC, p384DC},
		flags:           []string{"-expect-selected-credential", "1"},
		expectations: connectionExpectations{
			peerCertificate: p384DC,
		},
	})

	// Delegated credentials participate in issuer-based certificate selection.
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "DelegatedCredentials-MatchIssuer",
		config: Config{
			DelegatedCredentialAlgorithms: []signatureAlgorithm{signatureECDSAWithP256AndSHA256},
			// The client requested p256DCFromECDSA's issuer.
			RootCAs:     makeCertPoolFromRoots(p256DCFromECDSA),
			SendRootCAs: true,
		},
		shimCredentials: []*Credential{
			p256DC.WithMustMatchIssuer(true), p256DCFromECDSA.WithMustMatchIssuer(true)},
		flags: []string{"-expect-selected-credential", "1"},
		expectations: connectionExpectations{
			peerCertificate: p256DCFromECDSA,
		},
	})

}

type echCipher struct {
	name   string
	cipher HPKECipherSuite
}

var echCiphers = []echCipher{
	{
		name:   "HKDF-SHA256-AES-128-GCM",
		cipher: HPKECipherSuite{KDF: hpke.HKDFSHA256, AEAD: hpke.AES128GCM},
	},
	{
		name:   "HKDF-SHA256-AES-256-GCM",
		cipher: HPKECipherSuite{KDF: hpke.HKDFSHA256, AEAD: hpke.AES256GCM},
	},
	{
		name:   "HKDF-SHA256-ChaCha20-Poly1305",
		cipher: HPKECipherSuite{KDF: hpke.HKDFSHA256, AEAD: hpke.ChaCha20Poly1305},
	},
}

// generateServerECHConfig constructs a ServerECHConfig with a fresh X25519
// keypair and using |template| as a template for the ECHConfig. If fields are
// omitted, defaults are used.
func generateServerECHConfig(template *ECHConfig) ServerECHConfig {
	publicKey, secretKey, err := hpke.GenerateKeyPairX25519()
	if err != nil {
		panic(err)
	}
	templateCopy := *template
	if templateCopy.KEM == 0 {
		templateCopy.KEM = hpke.X25519WithHKDFSHA256
	}
	if len(templateCopy.PublicKey) == 0 {
		templateCopy.PublicKey = publicKey
	}
	if len(templateCopy.CipherSuites) == 0 {
		templateCopy.CipherSuites = make([]HPKECipherSuite, len(echCiphers))
		for i, cipher := range echCiphers {
			templateCopy.CipherSuites[i] = cipher.cipher
		}
	}
	if len(templateCopy.PublicName) == 0 {
		templateCopy.PublicName = "public.example"
	}
	if templateCopy.MaxNameLen == 0 {
		templateCopy.MaxNameLen = 64
	}
	return ServerECHConfig{ECHConfig: CreateECHConfig(&templateCopy), Key: secretKey}
}

func addEncryptedClientHelloTests() {
	// echConfig's ConfigID should match the one used in ssl/test/fuzzer.h.
	echConfig := generateServerECHConfig(&ECHConfig{ConfigID: 42})
	echConfig1 := generateServerECHConfig(&ECHConfig{ConfigID: 43})
	echConfig2 := generateServerECHConfig(&ECHConfig{ConfigID: 44})
	echConfig3 := generateServerECHConfig(&ECHConfig{ConfigID: 45})
	echConfigRepeatID := generateServerECHConfig(&ECHConfig{ConfigID: 42})

	echSecretCertificate := generateSingleCertChain(&x509.Certificate{
		SerialNumber: big.NewInt(57005),
		Subject: pkix.Name{
			CommonName: "test cert",
		},
		NotBefore:             time.Now().Add(-time.Hour),
		NotAfter:              time.Now().Add(time.Hour),
		DNSNames:              []string{"secret.example"},
		IsCA:                  true,
		BasicConstraintsValid: true,
	}, &rsa2048Key)
	echPublicCertificate := generateSingleCertChain(&x509.Certificate{
		SerialNumber: big.NewInt(57005),
		Subject: pkix.Name{
			CommonName: "test cert",
		},
		NotBefore:             time.Now().Add(-time.Hour),
		NotAfter:              time.Now().Add(time.Hour),
		DNSNames:              []string{"public.example"},
		IsCA:                  true,
		BasicConstraintsValid: true,
	}, &rsa2048Key)
	echLongNameCertificate := generateSingleCertChain(&x509.Certificate{
		SerialNumber: big.NewInt(57005),
		Subject: pkix.Name{
			CommonName: "test cert",
		},
		NotBefore:             time.Now().Add(-time.Hour),
		NotAfter:              time.Now().Add(time.Hour),
		DNSNames:              []string{"test0123456789.example"},
		IsCA:                  true,
		BasicConstraintsValid: true,
	}, &ecdsaP256Key)

	for _, protocol := range []protocol{tls, quic, dtls} {
		prefix := protocol.String() + "-"

		// There are two ClientHellos, so many of our tests have
		// HelloRetryRequest variations.
		for _, hrr := range []bool{false, true} {
			var suffix string
			var defaultCurves []CurveID
			if hrr {
				suffix = "-HelloRetryRequest"
				// Require a HelloRetryRequest for every curve.
				defaultCurves = []CurveID{}
			}

			// Test the server can accept ECH.
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server" + suffix,
				config: Config{
					ServerName:      "secret.example",
					ClientECHConfig: echConfig.ECHConfig,
					DefaultCurves:   defaultCurves,
				},
				resumeSession: true,
				flags: []string{
					"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig.Key),
					"-ech-is-retry-config", "1",
					"-expect-server-name", "secret.example",
					"-expect-ech-accept",
				},
				expectations: connectionExpectations{
					echAccepted: true,
				},
			})

			// Test the server can accept ECH with a minimal ClientHelloOuter.
			// This confirms that the server does not unexpectedly pick up
			// fields from the wrong ClientHello.
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server-MinimalClientHelloOuter" + suffix,
				config: Config{
					ServerName:      "secret.example",
					ClientECHConfig: echConfig.ECHConfig,
					DefaultCurves:   defaultCurves,
					Bugs: ProtocolBugs{
						MinimalClientHelloOuter: true,
					},
				},
				resumeSession: true,
				flags: []string{
					"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig.Key),
					"-ech-is-retry-config", "1",
					"-expect-server-name", "secret.example",
					"-expect-ech-accept",
				},
				expectations: connectionExpectations{
					echAccepted: true,
				},
			})

			// Test that the server can decline ECH. In particular, it must send
			// retry configs.
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server-Decline" + suffix,
				config: Config{
					ServerName:    "secret.example",
					DefaultCurves: defaultCurves,
					// The client uses an ECHConfig that the server does not understand
					// so we can observe which retry configs the server sends back.
					ClientECHConfig: echConfig.ECHConfig,
					Bugs: ProtocolBugs{
						OfferSessionInClientHelloOuter: true,
						ExpectECHRetryConfigs:          CreateECHConfigList(echConfig2.ECHConfig.Raw, echConfig3.ECHConfig.Raw),
					},
				},
				resumeSession: true,
				flags: []string{
					// Configure three ECHConfigs on the shim, only two of which
					// should be sent in retry configs.
					"-ech-server-config", base64FlagValue(echConfig1.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig1.Key),
					"-ech-is-retry-config", "0",
					"-ech-server-config", base64FlagValue(echConfig2.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig2.Key),
					"-ech-is-retry-config", "1",
					"-ech-server-config", base64FlagValue(echConfig3.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig3.Key),
					"-ech-is-retry-config", "1",
					"-expect-server-name", "public.example",
				},
			})

			// Test that the server considers a ClientHelloInner indicating TLS
			// 1.2 to be a fatal error.
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server-TLS12InInner" + suffix,
				config: Config{
					ServerName:      "secret.example",
					DefaultCurves:   defaultCurves,
					ClientECHConfig: echConfig.ECHConfig,
					Bugs: ProtocolBugs{
						AllowTLS12InClientHelloInner: true,
					},
				},
				flags: []string{
					"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig.Key),
					"-ech-is-retry-config", "1",
				},
				shouldFail:         true,
				expectedLocalError: "remote error: illegal parameter",
				expectedError:      ":INVALID_CLIENT_HELLO_INNER:",
			})

			// When inner ECH extension is absent from the ClientHelloInner, the
			// server should fail the connection.
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server-MissingECHInner" + suffix,
				config: Config{
					ServerName:      "secret.example",
					DefaultCurves:   defaultCurves,
					ClientECHConfig: echConfig.ECHConfig,
					Bugs: ProtocolBugs{
						OmitECHInner:       !hrr,
						OmitSecondECHInner: hrr,
					},
				},
				flags: []string{
					"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig.Key),
					"-ech-is-retry-config", "1",
				},
				shouldFail:         true,
				expectedLocalError: "remote error: illegal parameter",
				expectedError:      ":INVALID_CLIENT_HELLO_INNER:",
			})

			// Test that the server can decode ech_outer_extensions.
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server-OuterExtensions" + suffix,
				config: Config{
					ServerName:      "secret.example",
					DefaultCurves:   defaultCurves,
					ClientECHConfig: echConfig.ECHConfig,
					ECHOuterExtensions: []uint16{
						extensionKeyShare,
						extensionSupportedCurves,
						// Include a custom extension, to test that unrecognized
						// extensions are also decoded.
						extensionCustom,
					},
					Bugs: ProtocolBugs{
						CustomExtension:                    "test",
						OnlyCompressSecondClientHelloInner: hrr,
					},
				},
				flags: []string{
					"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig.Key),
					"-ech-is-retry-config", "1",
					"-expect-server-name", "secret.example",
					"-expect-ech-accept",
				},
				expectations: connectionExpectations{
					echAccepted: true,
				},
			})

			// Test that the server allows referenced ClientHelloOuter
			// extensions to be interleaved with other extensions. Only the
			// relative order must match.
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server-OuterExtensions-Interleaved" + suffix,
				config: Config{
					ServerName:      "secret.example",
					DefaultCurves:   defaultCurves,
					ClientECHConfig: echConfig.ECHConfig,
					ECHOuterExtensions: []uint16{
						extensionKeyShare,
						extensionSupportedCurves,
						extensionCustom,
					},
					Bugs: ProtocolBugs{
						CustomExtension:                    "test",
						OnlyCompressSecondClientHelloInner: hrr,
						ECHOuterExtensionOrder: []uint16{
							extensionServerName,
							extensionKeyShare,
							extensionSupportedVersions,
							extensionPSKKeyExchangeModes,
							extensionSupportedCurves,
							extensionSignatureAlgorithms,
							extensionCustom,
						},
					},
				},
				flags: []string{
					"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig.Key),
					"-ech-is-retry-config", "1",
					"-expect-server-name", "secret.example",
					"-expect-ech-accept",
				},
				expectations: connectionExpectations{
					echAccepted: true,
				},
			})

			// Test that the server rejects references to extensions in the
			// wrong order.
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server-OuterExtensions-WrongOrder" + suffix,
				config: Config{
					ServerName:      "secret.example",
					DefaultCurves:   defaultCurves,
					ClientECHConfig: echConfig.ECHConfig,
					ECHOuterExtensions: []uint16{
						extensionKeyShare,
						extensionSupportedCurves,
					},
					Bugs: ProtocolBugs{
						CustomExtension:                    "test",
						OnlyCompressSecondClientHelloInner: hrr,
						ECHOuterExtensionOrder: []uint16{
							extensionSupportedCurves,
							extensionKeyShare,
						},
					},
				},
				flags: []string{
					"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig.Key),
					"-ech-is-retry-config", "1",
					"-expect-server-name", "secret.example",
				},
				shouldFail:         true,
				expectedLocalError: "remote error: illegal parameter",
				expectedError:      ":INVALID_OUTER_EXTENSION:",
			})

			// Test that the server rejects duplicated values in ech_outer_extensions.
			// Besides causing the server to reconstruct an invalid ClientHelloInner
			// with duplicated extensions, this behavior would be vulnerable to DoS
			// attacks.
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server-OuterExtensions-Duplicate" + suffix,
				config: Config{
					ServerName:      "secret.example",
					DefaultCurves:   defaultCurves,
					ClientECHConfig: echConfig.ECHConfig,
					ECHOuterExtensions: []uint16{
						extensionSupportedCurves,
						extensionSupportedCurves,
					},
					Bugs: ProtocolBugs{
						OnlyCompressSecondClientHelloInner: hrr,
						// Don't duplicate the extension in ClientHelloOuter.
						ECHOuterExtensionOrder: []uint16{
							extensionSupportedCurves,
						},
					},
				},
				flags: []string{
					"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig.Key),
					"-ech-is-retry-config", "1",
				},
				shouldFail:         true,
				expectedLocalError: "remote error: illegal parameter",
				expectedError:      ":INVALID_OUTER_EXTENSION:",
			})

			// Test that the server rejects references to missing extensions in
			// ech_outer_extensions.
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server-OuterExtensions-Missing" + suffix,
				config: Config{
					ServerName:      "secret.example",
					DefaultCurves:   defaultCurves,
					ClientECHConfig: echConfig.ECHConfig,
					ECHOuterExtensions: []uint16{
						extensionCustom,
					},
					Bugs: ProtocolBugs{
						OnlyCompressSecondClientHelloInner: hrr,
					},
				},
				flags: []string{
					"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig.Key),
					"-ech-is-retry-config", "1",
					"-expect-server-name", "secret.example",
					"-expect-ech-accept",
				},
				shouldFail:         true,
				expectedLocalError: "remote error: illegal parameter",
				expectedError:      ":INVALID_OUTER_EXTENSION:",
			})

			// Test that the server rejects a references to the ECH extension in
			// ech_outer_extensions. The ECH extension is not authenticated in the
			// AAD and would result in an invalid ClientHelloInner.
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server-OuterExtensions-SelfReference" + suffix,
				config: Config{
					ServerName:      "secret.example",
					DefaultCurves:   defaultCurves,
					ClientECHConfig: echConfig.ECHConfig,
					ECHOuterExtensions: []uint16{
						extensionEncryptedClientHello,
					},
					Bugs: ProtocolBugs{
						OnlyCompressSecondClientHelloInner: hrr,
					},
				},
				flags: []string{
					"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig.Key),
					"-ech-is-retry-config", "1",
				},
				shouldFail:         true,
				expectedLocalError: "remote error: illegal parameter",
				expectedError:      ":INVALID_OUTER_EXTENSION:",
			})

			// Test the message callback is correctly reported with ECH.
			clientAndServerHello := "read hs 1\nread clienthelloinner\nwrite hs 2\n"
			expectMsgCallback := clientAndServerHello
			if protocol == tls {
				expectMsgCallback += "write ccs\n"
			}
			if hrr {
				expectMsgCallback += clientAndServerHello
			}
			// EncryptedExtensions onwards.
			expectMsgCallback += `write hs 8
write hs 11
write hs 15
write hs 20
read hs 20
write ack
write hs 4
write hs 4
read ack
read ack
`
			if protocol != dtls {
				expectMsgCallback = strings.ReplaceAll(expectMsgCallback, "write ack\n", "")
				expectMsgCallback = strings.ReplaceAll(expectMsgCallback, "read ack\n", "")
			}
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server-MessageCallback" + suffix,
				config: Config{
					ServerName:      "secret.example",
					ClientECHConfig: echConfig.ECHConfig,
					DefaultCurves:   defaultCurves,
					Bugs: ProtocolBugs{
						NoCloseNotify: true, // Align QUIC and TCP traces.
					},
				},
				flags: []string{
					"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig.Key),
					"-ech-is-retry-config", "1",
					"-expect-ech-accept",
					"-expect-msg-callback", expectMsgCallback,
				},
				expectations: connectionExpectations{
					echAccepted: true,
				},
			})
		}

		// Test that ECH, which runs before an async early callback, interacts
		// correctly in the state machine.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-AsyncEarlyCallback",
			config: Config{
				ServerName:      "secret.example",
				ClientECHConfig: echConfig.ECHConfig,
			},
			flags: []string{
				"-async",
				"-use-early-callback",
				"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
				"-ech-server-key", base64FlagValue(echConfig.Key),
				"-ech-is-retry-config", "1",
				"-expect-server-name", "secret.example",
				"-expect-ech-accept",
			},
			expectations: connectionExpectations{
				echAccepted: true,
			},
		})

		// Test that we successfully rewind the TLS state machine and disable ECH in the
		// case that the select_cert_cb signals that ECH is not possible for the SNI in
		// ClientHelloInner.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-FailCallbackNeedRewind",
			config: Config{
				ServerName:      "secret.example",
				ClientECHConfig: echConfig.ECHConfig,
			},
			flags: []string{
				"-async",
				"-fail-early-callback-ech-rewind",
				"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
				"-ech-server-key", base64FlagValue(echConfig.Key),
				"-ech-is-retry-config", "1",
				"-expect-server-name", "public.example",
			},
			expectations: connectionExpectations{
				echAccepted: false,
			},
		})

		// Test that we correctly handle falling back to a ClientHelloOuter with
		// no SNI (public name).
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-RewindWithNoPublicName",
			config: Config{
				ServerName:      "secret.example",
				ClientECHConfig: echConfig.ECHConfig,
				Bugs: ProtocolBugs{
					OmitPublicName: true,
				},
			},
			flags: []string{
				"-async",
				"-fail-early-callback-ech-rewind",
				"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
				"-ech-server-key", base64FlagValue(echConfig.Key),
				"-ech-is-retry-config", "1",
				"-expect-no-server-name",
			},
			expectations: connectionExpectations{
				echAccepted: false,
			},
		})

		// Test ECH-enabled server with two ECHConfigs can decrypt client's ECH when
		// it uses the second ECHConfig.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-SecondECHConfig",
			config: Config{
				ServerName:      "secret.example",
				ClientECHConfig: echConfig1.ECHConfig,
			},
			flags: []string{
				"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
				"-ech-server-key", base64FlagValue(echConfig.Key),
				"-ech-is-retry-config", "1",
				"-ech-server-config", base64FlagValue(echConfig1.ECHConfig.Raw),
				"-ech-server-key", base64FlagValue(echConfig1.Key),
				"-ech-is-retry-config", "1",
				"-expect-server-name", "secret.example",
				"-expect-ech-accept",
			},
			expectations: connectionExpectations{
				echAccepted: true,
			},
		})

		// Test ECH-enabled server with two ECHConfigs that have the same config
		// ID can decrypt client's ECH when it uses the second ECHConfig.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-RepeatedConfigID",
			config: Config{
				ServerName:      "secret.example",
				ClientECHConfig: echConfigRepeatID.ECHConfig,
			},
			flags: []string{
				"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
				"-ech-server-key", base64FlagValue(echConfig.Key),
				"-ech-is-retry-config", "1",
				"-ech-server-config", base64FlagValue(echConfigRepeatID.ECHConfig.Raw),
				"-ech-server-key", base64FlagValue(echConfigRepeatID.Key),
				"-ech-is-retry-config", "1",
				"-expect-server-name", "secret.example",
				"-expect-ech-accept",
			},
			expectations: connectionExpectations{
				echAccepted: true,
			},
		})

		// Test all supported ECH cipher suites.
		for i, cipher := range echCiphers {
			otherCipher := echCiphers[(i+1)%len(echCiphers)]

			// Test the ECH server can handle the specified cipher.
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server-Cipher-" + cipher.name,
				config: Config{
					ServerName:      "secret.example",
					ClientECHConfig: echConfig.ECHConfig,
					ECHCipherSuites: []HPKECipherSuite{cipher.cipher},
				},
				flags: []string{
					"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig.Key),
					"-ech-is-retry-config", "1",
					"-expect-server-name", "secret.example",
					"-expect-ech-accept",
				},
				expectations: connectionExpectations{
					echAccepted: true,
				},
			})

			// Test that client can offer the specified cipher and skip over
			// unrecognized ones.
			cipherConfig := generateServerECHConfig(&ECHConfig{
				ConfigID: 42,
				CipherSuites: []HPKECipherSuite{
					{KDF: 0x1111, AEAD: 0x2222},
					{KDF: cipher.cipher.KDF, AEAD: 0x2222},
					{KDF: 0x1111, AEAD: cipher.cipher.AEAD},
					cipher.cipher,
				},
			})
			testCases = append(testCases, testCase{
				testType: clientTest,
				protocol: protocol,
				name:     prefix + "ECH-Client-Cipher-" + cipher.name,
				config: Config{
					ServerECHConfigs: []ServerECHConfig{cipherConfig},
					Credential:       &echSecretCertificate,
				},
				flags: []string{
					"-ech-config-list", base64FlagValue(CreateECHConfigList(cipherConfig.ECHConfig.Raw)),
					"-host-name", "secret.example",
					"-expect-ech-accept",
				},
				expectations: connectionExpectations{
					echAccepted: true,
				},
			})

			// Test that the ECH server rejects the specified cipher if not
			// listed in its ECHConfig.
			otherCipherConfig := generateServerECHConfig(&ECHConfig{
				ConfigID:     42,
				CipherSuites: []HPKECipherSuite{otherCipher.cipher},
			})
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server-DisabledCipher-" + cipher.name,
				config: Config{
					ServerName:      "secret.example",
					ClientECHConfig: echConfig.ECHConfig,
					ECHCipherSuites: []HPKECipherSuite{cipher.cipher},
					Bugs: ProtocolBugs{
						ExpectECHRetryConfigs: CreateECHConfigList(otherCipherConfig.ECHConfig.Raw),
					},
				},
				flags: []string{
					"-ech-server-config", base64FlagValue(otherCipherConfig.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(otherCipherConfig.Key),
					"-ech-is-retry-config", "1",
					"-expect-server-name", "public.example",
				},
			})
		}

		// Test that the ECH server handles a short enc value by falling back to
		// ClientHelloOuter.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-ShortEnc",
			config: Config{
				ServerName:      "secret.example",
				ClientECHConfig: echConfig.ECHConfig,
				Bugs: ProtocolBugs{
					ExpectECHRetryConfigs: CreateECHConfigList(echConfig.ECHConfig.Raw),
					TruncateClientECHEnc:  true,
				},
			},
			flags: []string{
				"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
				"-ech-server-key", base64FlagValue(echConfig.Key),
				"-ech-is-retry-config", "1",
				"-expect-server-name", "public.example",
			},
		})

		// Test that the server handles decryption failure by falling back to
		// ClientHelloOuter.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-CorruptEncryptedClientHello",
			config: Config{
				ServerName:      "secret.example",
				ClientECHConfig: echConfig.ECHConfig,
				Bugs: ProtocolBugs{
					ExpectECHRetryConfigs:       CreateECHConfigList(echConfig.ECHConfig.Raw),
					CorruptEncryptedClientHello: true,
				},
			},
			flags: []string{
				"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
				"-ech-server-key", base64FlagValue(echConfig.Key),
				"-ech-is-retry-config", "1",
			},
		})

		// Test that the server treats decryption failure in the second
		// ClientHello as fatal.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-CorruptSecondEncryptedClientHello",
			config: Config{
				ServerName:      "secret.example",
				ClientECHConfig: echConfig.ECHConfig,
				// Force a HelloRetryRequest.
				DefaultCurves: []CurveID{},
				Bugs: ProtocolBugs{
					CorruptSecondEncryptedClientHello: true,
				},
			},
			flags: []string{
				"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
				"-ech-server-key", base64FlagValue(echConfig.Key),
				"-ech-is-retry-config", "1",
			},
			shouldFail:         true,
			expectedError:      ":DECRYPTION_FAILED:",
			expectedLocalError: "remote error: error decrypting message",
		})

		// Test that the server treats a missing second ECH extension as fatal.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-OmitSecondEncryptedClientHello",
			config: Config{
				ServerName:      "secret.example",
				ClientECHConfig: echConfig.ECHConfig,
				// Force a HelloRetryRequest.
				DefaultCurves: []CurveID{},
				Bugs: ProtocolBugs{
					OmitSecondEncryptedClientHello: true,
				},
			},
			flags: []string{
				"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
				"-ech-server-key", base64FlagValue(echConfig.Key),
				"-ech-is-retry-config", "1",
			},
			shouldFail:         true,
			expectedError:      ":MISSING_EXTENSION:",
			expectedLocalError: "remote error: missing extension",
		})

		// Test that the server treats a mismatched config ID in the second ClientHello as fatal.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-DifferentConfigIDSecondClientHello",
			config: Config{
				ServerName:      "secret.example",
				ClientECHConfig: echConfig.ECHConfig,
				// Force a HelloRetryRequest.
				DefaultCurves: []CurveID{},
				Bugs: ProtocolBugs{
					CorruptSecondEncryptedClientHelloConfigID: true,
				},
			},
			flags: []string{
				"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
				"-ech-server-key", base64FlagValue(echConfig.Key),
				"-ech-is-retry-config", "1",
			},
			shouldFail:         true,
			expectedError:      ":DECODE_ERROR:",
			expectedLocalError: "remote error: illegal parameter",
		})

		// Test early data works with ECH, in both accept and reject cases.
		// TODO(crbug.com/381113363): Enable these tests for DTLS once we
		// support early data in DTLS 1.3.
		if protocol != dtls {
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server-EarlyData",
				config: Config{
					ServerName:      "secret.example",
					ClientECHConfig: echConfig.ECHConfig,
				},
				resumeSession: true,
				earlyData:     true,
				flags: []string{
					"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig.Key),
					"-ech-is-retry-config", "1",
					"-expect-ech-accept",
				},
				expectations: connectionExpectations{
					echAccepted: true,
				},
			})
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server-EarlyDataRejected",
				config: Config{
					ServerName:      "secret.example",
					ClientECHConfig: echConfig.ECHConfig,
					Bugs: ProtocolBugs{
						// Cause the server to reject 0-RTT with a bad ticket age.
						SendTicketAge: 1 * time.Hour,
					},
				},
				resumeSession:           true,
				earlyData:               true,
				expectEarlyDataRejected: true,
				flags: []string{
					"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
					"-ech-server-key", base64FlagValue(echConfig.Key),
					"-ech-is-retry-config", "1",
					"-expect-ech-accept",
				},
				expectations: connectionExpectations{
					echAccepted: true,
				},
			})
		}

		// Test servers with ECH disabled correctly ignore the extension and
		// handshake with the ClientHelloOuter.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-Disabled",
			config: Config{
				ServerName:      "secret.example",
				ClientECHConfig: echConfig.ECHConfig,
			},
			flags: []string{
				"-expect-server-name", "public.example",
			},
		})

		// Test that ECH can be used with client certificates. In particular,
		// the name override logic should not interfere with the server.
		// Test the server can accept ECH.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-ClientAuth",
			config: Config{
				Credential:      &rsaCertificate,
				ClientECHConfig: echConfig.ECHConfig,
			},
			flags: []string{
				"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
				"-ech-server-key", base64FlagValue(echConfig.Key),
				"-ech-is-retry-config", "1",
				"-expect-ech-accept",
				"-require-any-client-certificate",
			},
			expectations: connectionExpectations{
				echAccepted: true,
			},
		})
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-Decline-ClientAuth",
			config: Config{
				Credential:      &rsaCertificate,
				ClientECHConfig: echConfig.ECHConfig,
				Bugs: ProtocolBugs{
					ExpectECHRetryConfigs: CreateECHConfigList(echConfig1.ECHConfig.Raw),
				},
			},
			flags: []string{
				"-ech-server-config", base64FlagValue(echConfig1.ECHConfig.Raw),
				"-ech-server-key", base64FlagValue(echConfig1.Key),
				"-ech-is-retry-config", "1",
				"-require-any-client-certificate",
			},
		})

		// Test that the server accepts padding.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-Padding",
			config: Config{
				ClientECHConfig: echConfig.ECHConfig,
				Bugs: ProtocolBugs{
					ClientECHPadding: 10,
				},
			},
			flags: []string{
				"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
				"-ech-server-key", base64FlagValue(echConfig.Key),
				"-ech-is-retry-config", "1",
				"-expect-ech-accept",
			},
			expectations: connectionExpectations{
				echAccepted: true,
			},
		})

		// Test that the server rejects bad padding.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-BadPadding",
			config: Config{
				ClientECHConfig: echConfig.ECHConfig,
				Bugs: ProtocolBugs{
					ClientECHPadding:    10,
					BadClientECHPadding: true,
				},
			},
			flags: []string{
				"-ech-server-config", base64FlagValue(echConfig.ECHConfig.Raw),
				"-ech-server-key", base64FlagValue(echConfig.Key),
				"-ech-is-retry-config", "1",
				"-expect-ech-accept",
			},
			expectations: connectionExpectations{
				echAccepted: true,
			},
			shouldFail:         true,
			expectedError:      ":DECODE_ERROR",
			expectedLocalError: "remote error: illegal parameter",
		})

		// Test the client's behavior when the server ignores ECH GREASE.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-GREASE-Client-TLS13",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					ExpectClientECH: true,
				},
			},
			flags: []string{"-enable-ech-grease"},
		})

		// Test the client's ECH GREASE behavior when responding to server's
		// HelloRetryRequest. This test implicitly checks that the first and second
		// ClientHello messages have identical ECH extensions.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-GREASE-Client-TLS13-HelloRetryRequest",
			config: Config{
				MaxVersion: VersionTLS13,
				MinVersion: VersionTLS13,
				// P-384 requires a HelloRetryRequest against BoringSSL's default
				// configuration. Assert this with ExpectMissingKeyShare.
				CurvePreferences: []CurveID{CurveP384},
				Bugs: ProtocolBugs{
					ExpectMissingKeyShare: true,
					ExpectClientECH:       true,
				},
			},
			flags: []string{"-enable-ech-grease", "-expect-hrr"},
		})

		unsupportedVersion := []byte{
			// version
			0xba, 0xdd,
			// length
			0x00, 0x05,
			// contents
			0x05, 0x04, 0x03, 0x02, 0x01,
		}

		// Test that the client accepts a well-formed encrypted_client_hello
		// extension in response to ECH GREASE. The response includes one ECHConfig
		// with a supported version and one with an unsupported version.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-GREASE-Client-TLS13-Retry-Configs",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					ExpectClientECH: true,
					// Include an additional well-formed ECHConfig with an
					// unsupported version. This ensures the client can skip
					// unsupported configs.
					SendECHRetryConfigs: CreateECHConfigList(echConfig.ECHConfig.Raw, unsupportedVersion),
				},
			},
			flags: []string{"-enable-ech-grease"},
		})

		// TLS 1.2 ServerHellos cannot contain retry configs.
		if protocol != quic {
			testCases = append(testCases, testCase{
				testType: clientTest,
				protocol: protocol,
				name:     prefix + "ECH-GREASE-Client-TLS12-RejectRetryConfigs",
				config: Config{
					MinVersion:       VersionTLS12,
					MaxVersion:       VersionTLS12,
					ServerECHConfigs: []ServerECHConfig{echConfig},
					Bugs: ProtocolBugs{
						ExpectClientECH:           true,
						AlwaysSendECHRetryConfigs: true,
					},
				},
				flags:              []string{"-enable-ech-grease"},
				shouldFail:         true,
				expectedLocalError: "remote error: unsupported extension",
				expectedError:      ":UNEXPECTED_EXTENSION:",
			})
			testCases = append(testCases, testCase{
				testType: clientTest,
				protocol: protocol,
				name:     prefix + "ECH-Client-TLS12-RejectRetryConfigs",
				config: Config{
					MinVersion:       VersionTLS12,
					MaxVersion:       VersionTLS12,
					ServerECHConfigs: []ServerECHConfig{echConfig},
					Bugs: ProtocolBugs{
						ExpectClientECH:           true,
						AlwaysSendECHRetryConfigs: true,
					},
				},
				flags: []string{
					"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig1.ECHConfig.Raw)),
				},
				shouldFail:         true,
				expectedLocalError: "remote error: unsupported extension",
				expectedError:      ":UNEXPECTED_EXTENSION:",
			})
		}

		// Retry configs must be rejected when ECH is accepted.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-Accept-RejectRetryConfigs",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{echConfig},
				Bugs: ProtocolBugs{
					ExpectClientECH:           true,
					AlwaysSendECHRetryConfigs: true,
				},
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
			},
			shouldFail:         true,
			expectedLocalError: "remote error: unsupported extension",
			expectedError:      ":UNEXPECTED_EXTENSION:",
		})

		// Unsolicited ECH HelloRetryRequest extensions should be rejected.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-UnsolictedHRRExtension",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{echConfig},
				CurvePreferences: []CurveID{CurveP384},
				Bugs: ProtocolBugs{
					AlwaysSendECHHelloRetryRequest: true,
					ExpectMissingKeyShare:          true, // Check we triggered HRR.
				},
			},
			shouldFail:         true,
			expectedLocalError: "remote error: unsupported extension",
			expectedError:      ":UNEXPECTED_EXTENSION:",
		})

		// GREASE should ignore ECH HelloRetryRequest extensions.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-GREASE-IgnoreHRRExtension",
			config: Config{
				CurvePreferences: []CurveID{CurveP384},
				Bugs: ProtocolBugs{
					AlwaysSendECHHelloRetryRequest: true,
					ExpectMissingKeyShare:          true, // Check we triggered HRR.
				},
			},
			flags: []string{"-enable-ech-grease"},
		})

		// Random ECH HelloRetryRequest extensions also signal ECH reject.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-Reject-RandomHRRExtension",
			config: Config{
				CurvePreferences: []CurveID{CurveP384},
				Bugs: ProtocolBugs{
					AlwaysSendECHHelloRetryRequest: true,
					ExpectMissingKeyShare:          true, // Check we triggered HRR.
				},
				Credential: &echPublicCertificate,
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
			},
			shouldFail:         true,
			expectedLocalError: "remote error: ECH required",
			expectedError:      ":ECH_REJECTED:",
		})

		// Test that the client aborts with a decode_error alert when it receives a
		// syntactically-invalid encrypted_client_hello extension from the server.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-GREASE-Client-TLS13-Invalid-Retry-Configs",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					ExpectClientECH:     true,
					SendECHRetryConfigs: []byte{0xba, 0xdd, 0xec, 0xcc},
				},
			},
			flags:              []string{"-enable-ech-grease"},
			shouldFail:         true,
			expectedLocalError: "remote error: error decoding message",
			expectedError:      ":ERROR_PARSING_EXTENSION:",
		})

		// Test that the server responds to an inner ECH extension with the
		// acceptance confirmation.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-ECHInner",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					AlwaysSendECHInner: true,
				},
			},
			resumeSession: true,
		})
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-ECHInner-HelloRetryRequest",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				// Force a HelloRetryRequest.
				DefaultCurves: []CurveID{},
				Bugs: ProtocolBugs{
					AlwaysSendECHInner: true,
				},
			},
			resumeSession: true,
		})

		// Test that server fails the handshake when it sees a non-empty
		// inner ECH extension.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     prefix + "ECH-Server-ECHInner-NotEmpty",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Bugs: ProtocolBugs{
					AlwaysSendECHInner:  true,
					SendInvalidECHInner: []byte{42, 42, 42},
				},
			},
			shouldFail:         true,
			expectedLocalError: "remote error: error decoding message",
			expectedError:      ":ERROR_PARSING_EXTENSION:",
		})

		// Test that a TLS 1.3 server that receives an inner ECH extension can
		// negotiate TLS 1.2 without clobbering the downgrade signal.
		if protocol != quic {
			testCases = append(testCases, testCase{
				testType: serverTest,
				protocol: protocol,
				name:     prefix + "ECH-Server-ECHInner-Absent-TLS12",
				config: Config{
					MinVersion: VersionTLS12,
					MaxVersion: VersionTLS13,
					Bugs: ProtocolBugs{
						// Omit supported_versions extension so the server negotiates
						// TLS 1.2.
						OmitSupportedVersions: true,
						AlwaysSendECHInner:    true,
					},
				},
				// Check that the client sees the TLS 1.3 downgrade signal in
				// ServerHello.random.
				shouldFail:         true,
				expectedLocalError: "tls: downgrade from TLS 1.3 detected",
			})
		}

		// Test the client can negotiate ECH, with and without HelloRetryRequest.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client",
			config: Config{
				MinVersion:       VersionTLS13,
				MaxVersion:       VersionTLS13,
				ServerECHConfigs: []ServerECHConfig{echConfig},
				Bugs: ProtocolBugs{
					ExpectServerName:      "secret.example",
					ExpectOuterServerName: "public.example",
				},
				Credential: &echSecretCertificate,
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-host-name", "secret.example",
				"-expect-ech-accept",
			},
			resumeSession: true,
			expectations:  connectionExpectations{echAccepted: true},
		})
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-HelloRetryRequest",
			config: Config{
				MinVersion:       VersionTLS13,
				MaxVersion:       VersionTLS13,
				CurvePreferences: []CurveID{CurveP384},
				ServerECHConfigs: []ServerECHConfig{echConfig},
				Bugs: ProtocolBugs{
					ExpectServerName:      "secret.example",
					ExpectOuterServerName: "public.example",
					ExpectMissingKeyShare: true, // Check we triggered HRR.
				},
				Credential: &echSecretCertificate,
			},
			resumeSession: true,
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-host-name", "secret.example",
				"-expect-ech-accept",
				"-expect-hrr", // Check we triggered HRR.
			},
			expectations: connectionExpectations{echAccepted: true},
		})

		// Test the client can negotiate ECH with early data.
		// TODO(crbug.com/381113363): Enable these tests for DTLS once we
		// support early data in DTLS 1.3.
		if protocol != dtls {
			testCases = append(testCases, testCase{
				testType: clientTest,
				protocol: protocol,
				name:     prefix + "ECH-Client-EarlyData",
				config: Config{
					MinVersion:       VersionTLS13,
					MaxVersion:       VersionTLS13,
					ServerECHConfigs: []ServerECHConfig{echConfig},
					Bugs: ProtocolBugs{
						ExpectServerName: "secret.example",
					},
					Credential: &echSecretCertificate,
				},
				flags: []string{
					"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
					"-host-name", "secret.example",
					"-expect-ech-accept",
				},
				resumeSession: true,
				earlyData:     true,
				expectations:  connectionExpectations{echAccepted: true},
			})
			testCases = append(testCases, testCase{
				testType: clientTest,
				protocol: protocol,
				name:     prefix + "ECH-Client-EarlyDataRejected",
				config: Config{
					MinVersion:       VersionTLS13,
					MaxVersion:       VersionTLS13,
					ServerECHConfigs: []ServerECHConfig{echConfig},
					Bugs: ProtocolBugs{
						ExpectServerName:      "secret.example",
						AlwaysRejectEarlyData: true,
					},
					Credential: &echSecretCertificate,
				},
				flags: []string{
					"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
					"-host-name", "secret.example",
					"-expect-ech-accept",
				},
				resumeSession:           true,
				earlyData:               true,
				expectEarlyDataRejected: true,
				expectations:            connectionExpectations{echAccepted: true},
			})
		}

		if protocol != quic {
			// Test that an ECH client does not offer a TLS 1.2 session.
			testCases = append(testCases, testCase{
				testType: clientTest,
				protocol: protocol,
				name:     prefix + "ECH-Client-TLS12SessionID",
				config: Config{
					MaxVersion:             VersionTLS12,
					SessionTicketsDisabled: true,
				},
				resumeConfig: &Config{
					ServerECHConfigs: []ServerECHConfig{echConfig},
					Bugs: ProtocolBugs{
						ExpectNoTLS12Session: true,
					},
				},
				flags: []string{
					"-on-resume-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
					"-on-resume-expect-ech-accept",
				},
				resumeSession:        true,
				expectResumeRejected: true,
				resumeExpectations:   &connectionExpectations{echAccepted: true},
			})
			testCases = append(testCases, testCase{
				testType: clientTest,
				protocol: protocol,
				name:     prefix + "ECH-Client-TLS12SessionTicket",
				config: Config{
					MaxVersion: VersionTLS12,
				},
				resumeConfig: &Config{
					ServerECHConfigs: []ServerECHConfig{echConfig},
					Bugs: ProtocolBugs{
						ExpectNoTLS12Session: true,
					},
				},
				flags: []string{
					"-on-resume-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
					"-on-resume-expect-ech-accept",
				},
				resumeSession:        true,
				expectResumeRejected: true,
				resumeExpectations:   &connectionExpectations{echAccepted: true},
			})
		}

		// ClientHelloInner should not include NPN, which is a TLS 1.2-only
		// extensions. The Go server will enforce this, so this test only needs
		// to configure the feature on the shim. Other application extensions
		// are sent implicitly.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-NoNPN",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{echConfig},
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-expect-ech-accept",
				// Enable NPN.
				"-select-next-proto", "foo",
			},
			expectations: connectionExpectations{echAccepted: true},
		})

		// Test that the client iterates over configurations in the
		// ECHConfigList and selects the first with supported parameters.
		unsupportedKEM := generateServerECHConfig(&ECHConfig{
			KEM:       0x6666,
			PublicKey: []byte{1, 2, 3, 4},
		}).ECHConfig
		unsupportedCipherSuites := generateServerECHConfig(&ECHConfig{
			CipherSuites: []HPKECipherSuite{{0x1111, 0x2222}},
		}).ECHConfig
		unsupportedMandatoryExtension := generateServerECHConfig(&ECHConfig{
			UnsupportedMandatoryExtension: true,
		}).ECHConfig
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-SelectECHConfig",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{echConfig},
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(
					unsupportedVersion,
					unsupportedKEM.Raw,
					unsupportedCipherSuites.Raw,
					unsupportedMandatoryExtension.Raw,
					echConfig.ECHConfig.Raw,
					// |echConfig1| is also supported, but the client should
					// select the first one.
					echConfig1.ECHConfig.Raw,
				)),
				"-expect-ech-accept",
			},
			expectations: connectionExpectations{
				echAccepted: true,
			},
		})

		// Test that the client skips sending ECH if all ECHConfigs are
		// unsupported.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-NoSupportedConfigs",
			config: Config{
				Bugs: ProtocolBugs{
					ExpectNoClientECH: true,
				},
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(
					unsupportedVersion,
					unsupportedKEM.Raw,
					unsupportedCipherSuites.Raw,
					unsupportedMandatoryExtension.Raw,
				)),
			},
		})

		// If ECH GREASE is enabled, the client should send ECH GREASE when no
		// configured ECHConfig is suitable.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-NoSupportedConfigs-GREASE",
			config: Config{
				Bugs: ProtocolBugs{
					ExpectClientECH: true,
				},
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(
					unsupportedVersion,
					unsupportedKEM.Raw,
					unsupportedCipherSuites.Raw,
					unsupportedMandatoryExtension.Raw,
				)),
				"-enable-ech-grease",
			},
		})

		// If both ECH GREASE and suitable ECHConfigs are available, the
		// client should send normal ECH.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-GREASE",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{echConfig},
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-expect-ech-accept",
			},
			resumeSession: true,
			expectations:  connectionExpectations{echAccepted: true},
		})

		// Test that GREASE extensions correctly interact with ECH. Both the
		// inner and outer ClientHellos should include GREASE extensions.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-GREASEExtensions",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{echConfig},
				Bugs: ProtocolBugs{
					ExpectGREASE: true,
				},
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-expect-ech-accept",
				"-enable-grease",
			},
			resumeSession: true,
			expectations:  connectionExpectations{echAccepted: true},
		})

		// Test that the client tolerates unsupported extensions if the
		// mandatory bit is not set.
		unsupportedExtension := generateServerECHConfig(&ECHConfig{UnsupportedExtension: true})
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-UnsupportedExtension",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{unsupportedExtension},
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(unsupportedExtension.ECHConfig.Raw)),
				"-expect-ech-accept",
			},
			expectations: connectionExpectations{echAccepted: true},
		})

		// Syntax errors in the ECHConfigList should be rejected.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-InvalidECHConfigList",
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw[1:])),
			},
			shouldFail:    true,
			expectedError: ":INVALID_ECH_CONFIG_LIST:",
		})

		// If the ClientHelloInner has no server_name extension, while the
		// ClientHelloOuter has one, the client must check for unsolicited
		// extensions based on the selected ClientHello.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-UnsolicitedInnerServerNameAck",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{echConfig},
				Bugs: ProtocolBugs{
					// ClientHelloOuter should have a server name.
					ExpectOuterServerName: "public.example",
					// The server will acknowledge the server_name extension.
					// This option runs whether or not the client requested the
					// extension.
					SendServerNameAck: true,
				},
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				// No -host-name flag.
				"-expect-ech-accept",
			},
			shouldFail:         true,
			expectedError:      ":UNEXPECTED_EXTENSION:",
			expectedLocalError: "remote error: unsupported extension",
			expectations:       connectionExpectations{echAccepted: true},
		})

		// Most extensions are the same between ClientHelloInner and
		// ClientHelloOuter and can be compressed.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-ExpectECHOuterExtensions",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{echConfig},
				NextProtos:       []string{"proto"},
				Bugs: ProtocolBugs{
					ExpectECHOuterExtensions: []uint16{
						extensionALPN,
						extensionKeyShare,
						extensionPSKKeyExchangeModes,
						extensionSignatureAlgorithms,
						extensionSupportedCurves,
					},
				},
				Credential: &echSecretCertificate,
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-expect-ech-accept",
				"-advertise-alpn", "\x05proto",
				"-expect-alpn", "proto",
				"-host-name", "secret.example",
			},
			expectations: connectionExpectations{
				echAccepted: true,
				nextProto:   "proto",
			},
			skipQUICALPNConfig: true,
		})

		// If the server name happens to match the public name, it still should
		// not be compressed. It is not publicly known that they match.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-NeverCompressServerName",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{echConfig},
				NextProtos:       []string{"proto"},
				Bugs: ProtocolBugs{
					ExpectECHUncompressedExtensions: []uint16{extensionServerName},
					ExpectServerName:                "public.example",
					ExpectOuterServerName:           "public.example",
				},
				Credential: &echPublicCertificate,
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-expect-ech-accept",
				"-host-name", "public.example",
			},
			expectations: connectionExpectations{echAccepted: true},
		})

		// If the ClientHelloOuter disables TLS 1.3, e.g. in QUIC, the client
		// should also compress supported_versions.
		tls13Vers := VersionTLS13
		if protocol == dtls {
			tls13Vers = VersionDTLS13
		}
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-CompressSupportedVersions",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{echConfig},
				Bugs: ProtocolBugs{
					ExpectECHOuterExtensions: []uint16{
						extensionSupportedVersions,
					},
				},
				Credential: &echSecretCertificate,
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-host-name", "secret.example",
				"-expect-ech-accept",
				"-min-version", strconv.Itoa(int(tls13Vers)),
			},
			expectations: connectionExpectations{echAccepted: true},
		})

		// Test that the client can still offer server names that exceed the
		// maximum name length. It is only a padding hint.
		maxNameLen10 := generateServerECHConfig(&ECHConfig{MaxNameLen: 10})
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-NameTooLong",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{maxNameLen10},
				Bugs: ProtocolBugs{
					ExpectServerName: "test0123456789.example",
				},
				Credential: &echLongNameCertificate,
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(maxNameLen10.ECHConfig.Raw)),
				"-host-name", "test0123456789.example",
				"-expect-ech-accept",
			},
			expectations: connectionExpectations{echAccepted: true},
		})

		// Test the client can recognize when ECH is rejected.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-Reject",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{echConfig2, echConfig3},
				Bugs: ProtocolBugs{
					ExpectServerName: "public.example",
				},
				Credential: &echPublicCertificate,
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-expect-ech-retry-configs", base64FlagValue(CreateECHConfigList(echConfig2.ECHConfig.Raw, echConfig3.ECHConfig.Raw)),
			},
			shouldFail:         true,
			expectedLocalError: "remote error: ECH required",
			expectedError:      ":ECH_REJECTED:",
		})
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-Reject-HelloRetryRequest",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{echConfig2, echConfig3},
				CurvePreferences: []CurveID{CurveP384},
				Bugs: ProtocolBugs{
					ExpectServerName:      "public.example",
					ExpectMissingKeyShare: true, // Check we triggered HRR.
				},
				Credential: &echPublicCertificate,
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-expect-ech-retry-configs", base64FlagValue(CreateECHConfigList(echConfig2.ECHConfig.Raw, echConfig3.ECHConfig.Raw)),
				"-expect-hrr", // Check we triggered HRR.
			},
			shouldFail:         true,
			expectedLocalError: "remote error: ECH required",
			expectedError:      ":ECH_REJECTED:",
		})
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-Reject-NoRetryConfigs",
			config: Config{
				Bugs: ProtocolBugs{
					ExpectServerName: "public.example",
				},
				Credential: &echPublicCertificate,
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-expect-no-ech-retry-configs",
			},
			shouldFail:         true,
			expectedLocalError: "remote error: ECH required",
			expectedError:      ":ECH_REJECTED:",
		})
		if protocol != quic {
			testCases = append(testCases, testCase{
				testType: clientTest,
				protocol: protocol,
				name:     prefix + "ECH-Client-Reject-TLS12",
				config: Config{
					MaxVersion: VersionTLS12,
					Bugs: ProtocolBugs{
						ExpectServerName: "public.example",
					},
					Credential: &echPublicCertificate,
				},
				flags: []string{
					"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
					// TLS 1.2 cannot provide retry configs.
					"-expect-no-ech-retry-configs",
				},
				shouldFail:         true,
				expectedLocalError: "remote error: ECH required",
				expectedError:      ":ECH_REJECTED:",
			})

			// Test that the client disables False Start when ECH is rejected.
			testCases = append(testCases, testCase{
				protocol: protocol,
				name:     prefix + "ECH-Client-Reject-TLS12-NoFalseStart",
				config: Config{
					MaxVersion:   VersionTLS12,
					CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
					NextProtos:   []string{"foo"},
					Bugs: ProtocolBugs{
						// The options below cause the server to, immediately
						// after client Finished, send an alert and try to read
						// application data without sending server Finished.
						ExpectFalseStart:          true,
						AlertBeforeFalseStartTest: alertAccessDenied,
					},
					Credential: &echPublicCertificate,
				},
				flags: []string{
					"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
					"-false-start",
					"-advertise-alpn", "\x03foo",
					"-expect-alpn", "foo",
				},
				shimWritesFirst: true,
				shouldFail:      true,
				// Ensure the client does not send application data at the False
				// Start point. EOF comes from the client closing the connection
				// in response ot the alert.
				expectedLocalError: "tls: peer did not false start: EOF",
				// Ensures the client picks up the alert before reporting an
				// authenticated |SSL_R_ECH_REJECTED|.
				expectedError: ":TLSV1_ALERT_ACCESS_DENIED:",
			})
		}

		// Test that unsupported retry configs in a valid ECHConfigList are
		// allowed. They will be skipped when configured in the retry.
		retryConfigs := CreateECHConfigList(
			unsupportedVersion,
			unsupportedKEM.Raw,
			unsupportedCipherSuites.Raw,
			unsupportedMandatoryExtension.Raw,
			echConfig2.ECHConfig.Raw)
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-Reject-UnsupportedRetryConfigs",
			config: Config{
				Bugs: ProtocolBugs{
					SendECHRetryConfigs: retryConfigs,
					ExpectServerName:    "public.example",
				},
				Credential: &echPublicCertificate,
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-expect-ech-retry-configs", base64FlagValue(retryConfigs),
			},
			shouldFail:         true,
			expectedLocalError: "remote error: ECH required",
			expectedError:      ":ECH_REJECTED:",
		})

		// Test that the client rejects ClientHelloOuter handshakes that attempt
		// to resume the ClientHelloInner's ticket, at TLS 1.2 and TLS 1.3.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-Reject-ResumeInnerSession-TLS13",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{echConfig},
				Bugs: ProtocolBugs{
					ExpectServerName: "secret.example",
				},
				Credential: &echSecretCertificate,
			},
			resumeConfig: &Config{
				MaxVersion:       VersionTLS13,
				ServerECHConfigs: []ServerECHConfig{echConfig},
				Bugs: ProtocolBugs{
					ExpectServerName:                    "public.example",
					UseInnerSessionWithClientHelloOuter: true,
				},
				Credential: &echPublicCertificate,
			},
			resumeSession: true,
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-host-name", "secret.example",
				"-on-initial-expect-ech-accept",
			},
			shouldFail:         true,
			expectedError:      ":UNEXPECTED_EXTENSION:",
			expectations:       connectionExpectations{echAccepted: true},
			resumeExpectations: &connectionExpectations{echAccepted: false},
		})
		if protocol == tls {
			// This is only syntactically possible with TLS. In DTLS, we don't
			// have middlebox compatibility mode, so the session ID will only
			// filled in if we are offering a DTLS 1.2 session. But a DTLS 1.2
			// would never be offered in ClientHelloInner. Without a session ID,
			// the server syntactically cannot express a resumption at DTLS 1.2.
			// In QUIC, the above is true, and 1.2 does not exist anyway.
			testCases = append(testCases, testCase{
				testType: clientTest,
				protocol: protocol,
				name:     prefix + "ECH-Client-Reject-ResumeInnerSession-TLS12",
				config: Config{
					ServerECHConfigs: []ServerECHConfig{echConfig},
					Bugs: ProtocolBugs{
						ExpectServerName: "secret.example",
					},
					Credential: &echSecretCertificate,
				},
				resumeConfig: &Config{
					MinVersion:       VersionTLS12,
					MaxVersion:       VersionTLS12,
					ServerECHConfigs: []ServerECHConfig{echConfig},
					Bugs: ProtocolBugs{
						ExpectServerName:                    "public.example",
						UseInnerSessionWithClientHelloOuter: true,
						// The client only ever offers TLS 1.3 sessions in
						// ClientHelloInner. AcceptAnySession allows them to be
						// resumed at TLS 1.2.
						AcceptAnySession: true,
					},
					Credential: &echPublicCertificate,
				},
				resumeSession: true,
				flags: []string{
					"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
					"-host-name", "secret.example",
					"-on-initial-expect-ech-accept",
				},
				// From the client's perspective, the server echoed a session ID to
				// signal resumption, but the selected ClientHello had nothing to
				// resume.
				shouldFail:         true,
				expectedError:      ":SERVER_ECHOED_INVALID_SESSION_ID:",
				expectedLocalError: "remote error: illegal parameter",
				expectations:       connectionExpectations{echAccepted: true},
				resumeExpectations: &connectionExpectations{echAccepted: false},
			})
		}

		// Test that the client can process ECH rejects after an early data reject.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-Reject-EarlyDataRejected",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{echConfig},
				Bugs: ProtocolBugs{
					ExpectServerName: "secret.example",
				},
				Credential: &echSecretCertificate,
			},
			resumeConfig: &Config{
				ServerECHConfigs: []ServerECHConfig{echConfig2},
				Bugs: ProtocolBugs{
					ExpectServerName: "public.example",
				},
				Credential: &echPublicCertificate,
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-host-name", "secret.example",
				// Although the resumption connection does not accept ECH, the
				// API will report ECH was accepted at the 0-RTT point.
				"-expect-ech-accept",
				// -on-retry refers to the retried handshake after 0-RTT reject,
				// while ech-retry-configs refers to the ECHConfigs to use in
				// the next connection attempt.
				"-on-retry-expect-ech-retry-configs", base64FlagValue(CreateECHConfigList(echConfig2.ECHConfig.Raw)),
			},
			resumeSession:           true,
			expectResumeRejected:    true,
			earlyData:               true,
			expectEarlyDataRejected: true,
			expectations:            connectionExpectations{echAccepted: true},
			resumeExpectations:      &connectionExpectations{echAccepted: false},
			shouldFail:              true,
			expectedLocalError:      "remote error: ECH required",
			expectedError:           ":ECH_REJECTED:",
		})
		// TODO(crbug.com/381113363): Enable this test for DTLS once we
		// support early data in DTLS 1.3.
		if protocol != quic && protocol != dtls {
			testCases = append(testCases, testCase{
				testType: clientTest,
				protocol: protocol,
				name:     prefix + "ECH-Client-Reject-EarlyDataRejected-TLS12",
				config: Config{
					ServerECHConfigs: []ServerECHConfig{echConfig},
					Bugs: ProtocolBugs{
						ExpectServerName: "secret.example",
					},
					Credential: &echSecretCertificate,
				},
				resumeConfig: &Config{
					MaxVersion: VersionTLS12,
					Bugs: ProtocolBugs{
						ExpectServerName: "public.example",
					},
					Credential: &echPublicCertificate,
				},
				flags: []string{
					"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
					"-host-name", "secret.example",
					// Although the resumption connection does not accept ECH, the
					// API will report ECH was accepted at the 0-RTT point.
					"-expect-ech-accept",
				},
				resumeSession:           true,
				expectResumeRejected:    true,
				earlyData:               true,
				expectEarlyDataRejected: true,
				expectations:            connectionExpectations{echAccepted: true},
				resumeExpectations:      &connectionExpectations{echAccepted: false},
				// ClientHellos with early data cannot negotiate TLS 1.2, with
				// or without ECH. The shim should first report
				// |SSL_R_WRONG_VERSION_ON_EARLY_DATA|. The caller will then
				// repair the first error by retrying without early data. That
				// will look like ECH-Client-Reject-TLS12 and select TLS 1.2
				// and ClientHelloOuter. The caller will then trigger a third
				// attempt, which will succeed.
				shouldFail:    true,
				expectedError: ":WRONG_VERSION_ON_EARLY_DATA:",
			})
		}

		// Test that the client ignores ECHConfigs with invalid public names.
		invalidPublicName := generateServerECHConfig(&ECHConfig{PublicName: "dns_names_have_no_underscores.example"})
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-SkipInvalidPublicName",
			config: Config{
				Bugs: ProtocolBugs{
					// No ECHConfigs are supported, so the client should fall
					// back to cleartext.
					ExpectNoClientECH: true,
					ExpectServerName:  "secret.example",
				},
				Credential: &echSecretCertificate,
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(invalidPublicName.ECHConfig.Raw)),
				"-host-name", "secret.example",
			},
		})
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-SkipInvalidPublicName-2",
			config: Config{
				// The client should skip |invalidPublicName| and use |echConfig|.
				ServerECHConfigs: []ServerECHConfig{echConfig},
				Bugs: ProtocolBugs{
					ExpectOuterServerName: "public.example",
					ExpectServerName:      "secret.example",
				},
				Credential: &echSecretCertificate,
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(invalidPublicName.ECHConfig.Raw, echConfig.ECHConfig.Raw)),
				"-host-name", "secret.example",
				"-expect-ech-accept",
			},
			expectations: connectionExpectations{echAccepted: true},
		})

		// Test both sync and async mode, to test both with and without the
		// client certificate callback.
		for _, async := range []bool{false, true} {
			var flags []string
			var suffix string
			if async {
				flags = []string{"-async"}
				suffix = "-Async"
			}

			// Test that ECH and client certificates can be used together.
			testCases = append(testCases, testCase{
				testType: clientTest,
				protocol: protocol,
				name:     prefix + "ECH-Client-ClientCertificate" + suffix,
				config: Config{
					ServerECHConfigs: []ServerECHConfig{echConfig},
					ClientAuth:       RequireAnyClientCert,
				},
				shimCertificate: &rsaCertificate,
				flags: append([]string{
					"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
					"-expect-ech-accept",
				}, flags...),
				expectations: connectionExpectations{echAccepted: true},
			})

			// Test that, when ECH is rejected, the client does not send a client
			// certificate.
			testCases = append(testCases, testCase{
				testType: clientTest,
				protocol: protocol,
				name:     prefix + "ECH-Client-Reject-NoClientCertificate-TLS13" + suffix,
				config: Config{
					MinVersion: VersionTLS13,
					MaxVersion: VersionTLS13,
					ClientAuth: RequireAnyClientCert,
					Credential: &echPublicCertificate,
				},
				shimCertificate: &rsaCertificate,
				flags: append([]string{
					"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				}, flags...),
				shouldFail:         true,
				expectedLocalError: "tls: client didn't provide a certificate",
			})
			if protocol != quic {
				testCases = append(testCases, testCase{
					testType: clientTest,
					protocol: protocol,
					name:     prefix + "ECH-Client-Reject-NoClientCertificate-TLS12" + suffix,
					config: Config{
						MinVersion: VersionTLS12,
						MaxVersion: VersionTLS12,
						ClientAuth: RequireAnyClientCert,
						Credential: &echPublicCertificate,
					},
					shimCertificate: &rsaCertificate,
					flags: append([]string{
						"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
					}, flags...),
					shouldFail:         true,
					expectedLocalError: "tls: client didn't provide a certificate",
				})
			}
		}

		// Test that ECH and Channel ID can be used together. Channel ID does
		// not exist in DTLS.
		if protocol != dtls {
			testCases = append(testCases, testCase{
				testType: clientTest,
				protocol: protocol,
				name:     prefix + "ECH-Client-ChannelID",
				config: Config{
					ServerECHConfigs: []ServerECHConfig{echConfig},
					RequestChannelID: true,
				},
				flags: []string{
					"-send-channel-id", channelIDKeyPath,
					"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
					"-expect-ech-accept",
				},
				resumeSession: true,
				expectations: connectionExpectations{
					channelID:   true,
					echAccepted: true,
				},
			})

			// Handshakes where ECH is rejected do not offer or accept Channel ID.
			testCases = append(testCases, testCase{
				testType: clientTest,
				protocol: protocol,
				name:     prefix + "ECH-Client-Reject-NoChannelID-TLS13",
				config: Config{
					MinVersion: VersionTLS13,
					MaxVersion: VersionTLS13,
					Bugs: ProtocolBugs{
						AlwaysNegotiateChannelID: true,
					},
					Credential: &echPublicCertificate,
				},
				flags: []string{
					"-send-channel-id", channelIDKeyPath,
					"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				},
				shouldFail:         true,
				expectedLocalError: "remote error: unsupported extension",
				expectedError:      ":UNEXPECTED_EXTENSION:",
			})
			if protocol != quic {
				testCases = append(testCases, testCase{
					testType: clientTest,
					protocol: protocol,
					name:     prefix + "ECH-Client-Reject-NoChannelID-TLS12",
					config: Config{
						MinVersion: VersionTLS12,
						MaxVersion: VersionTLS12,
						Bugs: ProtocolBugs{
							AlwaysNegotiateChannelID: true,
						},
						Credential: &echPublicCertificate,
					},
					flags: []string{
						"-send-channel-id", channelIDKeyPath,
						"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
					},
					shouldFail:         true,
					expectedLocalError: "remote error: unsupported extension",
					expectedError:      ":UNEXPECTED_EXTENSION:",
				})
			}
		}

		// Test that ECH correctly overrides the host name for certificate
		// verification.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-NotOffered-NoOverrideName",
			flags: []string{
				"-verify-peer",
				"-use-custom-verify-callback",
				// When not offering ECH, verify the usual name in both full
				// and resumption handshakes.
				"-reverify-on-resume",
				"-expect-no-ech-name-override",
			},
			resumeSession: true,
		})
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-GREASE-NoOverrideName",
			flags: []string{
				"-verify-peer",
				"-use-custom-verify-callback",
				"-enable-ech-grease",
				// When offering ECH GREASE, verify the usual name in both full
				// and resumption handshakes.
				"-reverify-on-resume",
				"-expect-no-ech-name-override",
			},
			resumeSession: true,
		})
		if protocol != quic {
			testCases = append(testCases, testCase{
				testType: clientTest,
				protocol: protocol,
				name:     prefix + "ECH-Client-Rejected-OverrideName-TLS12",
				config: Config{
					MinVersion: VersionTLS12,
					MaxVersion: VersionTLS12,
				},
				flags: []string{
					"-verify-peer",
					"-use-custom-verify-callback",
					"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
					// When ECH is rejected, verify the public name. This can
					// only happen in full handshakes.
					"-expect-ech-name-override", "public.example",
				},
				shouldFail:         true,
				expectedError:      ":ECH_REJECTED:",
				expectedLocalError: "remote error: ECH required",
			})
		}
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-Reject-OverrideName-TLS13",
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Credential: &echPublicCertificate,
			},
			flags: []string{
				"-verify-peer",
				"-use-custom-verify-callback",
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				// When ECH is rejected, verify the public name. This can
				// only happen in full handshakes.
				"-expect-ech-name-override", "public.example",
			},
			shouldFail:         true,
			expectedError:      ":ECH_REJECTED:",
			expectedLocalError: "remote error: ECH required",
		})
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-Accept-NoOverrideName",
			config: Config{
				ServerECHConfigs: []ServerECHConfig{echConfig},
			},
			flags: []string{
				"-verify-peer",
				"-use-custom-verify-callback",
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-expect-ech-accept",
				// When ECH is accepted, verify the usual name in both full and
				// resumption handshakes.
				"-reverify-on-resume",
				"-expect-no-ech-name-override",
			},
			resumeSession: true,
			expectations:  connectionExpectations{echAccepted: true},
		})
		// TODO(crbug.com/381113363): Enable this test for DTLS once we
		// support early data in DTLS 1.3.
		if protocol != dtls {
			testCases = append(testCases, testCase{
				testType: clientTest,
				protocol: protocol,
				name:     prefix + "ECH-Client-Reject-EarlyDataRejected-OverrideNameOnRetry",
				config: Config{
					ServerECHConfigs: []ServerECHConfig{echConfig},
					Credential:       &echPublicCertificate,
				},
				resumeConfig: &Config{
					Credential: &echPublicCertificate,
				},
				flags: []string{
					"-verify-peer",
					"-use-custom-verify-callback",
					"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
					// Although the resumption connection does not accept ECH, the
					// API will report ECH was accepted at the 0-RTT point.
					"-expect-ech-accept",
					// The resumption connection verifies certificates twice. First,
					// if reverification is enabled, we verify the 0-RTT certificate
					// as if ECH as accepted. There should be no name override.
					// Next, on the post-0-RTT-rejection retry, we verify the new
					// server certificate. This picks up the ECH reject, so it
					// should use public.example.
					"-reverify-on-resume",
					"-on-resume-expect-no-ech-name-override",
					"-on-retry-expect-ech-name-override", "public.example",
				},
				resumeSession:           true,
				expectResumeRejected:    true,
				earlyData:               true,
				expectEarlyDataRejected: true,
				expectations:            connectionExpectations{echAccepted: true},
				resumeExpectations:      &connectionExpectations{echAccepted: false},
				shouldFail:              true,
				expectedError:           ":ECH_REJECTED:",
				expectedLocalError:      "remote error: ECH required",
			})
		}

		// Test that the client checks both HelloRetryRequest and ServerHello
		// for a confirmation signal.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-HelloRetryRequest-MissingServerHelloConfirmation",
			config: Config{
				MinVersion:       VersionTLS13,
				MaxVersion:       VersionTLS13,
				CurvePreferences: []CurveID{CurveP384},
				ServerECHConfigs: []ServerECHConfig{echConfig},
				Bugs: ProtocolBugs{
					ExpectMissingKeyShare:          true, // Check we triggered HRR.
					OmitServerHelloECHConfirmation: true,
				},
			},
			resumeSession: true,
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-expect-hrr", // Check we triggered HRR.
			},
			shouldFail:    true,
			expectedError: ":INCONSISTENT_ECH_NEGOTIATION:",
		})

		// Test the message callback is correctly reported, with and without
		// HelloRetryRequest.
		clientAndServerHello := "write clienthelloinner\nwrite hs 1\nread hs 2\n"
		clientAndServerHelloInitial := clientAndServerHello
		if protocol == tls {
			clientAndServerHelloInitial += "write ccs\n"
		}
		// EncryptedExtensions onwards.
		finishHandshake := `read hs 8
read hs 11
read hs 15
read hs 20
write hs 20
read ack
read hs 4
read hs 4
`
		if protocol != dtls {
			finishHandshake = strings.ReplaceAll(finishHandshake, "read ack\n", "")
		}
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-MessageCallback",
			config: Config{
				MinVersion:       VersionTLS13,
				MaxVersion:       VersionTLS13,
				ServerECHConfigs: []ServerECHConfig{echConfig},
				Bugs: ProtocolBugs{
					NoCloseNotify: true, // Align QUIC and TCP traces.
				},
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-expect-ech-accept",
				"-expect-msg-callback", clientAndServerHelloInitial + finishHandshake,
			},
			expectations: connectionExpectations{echAccepted: true},
		})
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     prefix + "ECH-Client-MessageCallback-HelloRetryRequest",
			config: Config{
				MinVersion:       VersionTLS13,
				MaxVersion:       VersionTLS13,
				CurvePreferences: []CurveID{CurveP384},
				ServerECHConfigs: []ServerECHConfig{echConfig},
				Bugs: ProtocolBugs{
					ExpectMissingKeyShare: true, // Check we triggered HRR.
					NoCloseNotify:         true, // Align QUIC and TCP traces.
				},
			},
			flags: []string{
				"-ech-config-list", base64FlagValue(CreateECHConfigList(echConfig.ECHConfig.Raw)),
				"-expect-ech-accept",
				"-expect-hrr", // Check we triggered HRR.
				"-expect-msg-callback", clientAndServerHelloInitial + clientAndServerHello + finishHandshake,
			},
			expectations: connectionExpectations{echAccepted: true},
		})
	}
}

func addHintMismatchTests() {
	// Each of these tests skips split handshakes because split handshakes does
	// not handle a mismatch between shim and handshaker. Handshake hints,
	// however, are designed to tolerate the mismatch.
	//
	// Note also these tests do not specify -handshake-hints directly. Instead,
	// we define normal tests, that run even without a handshaker, and rely on
	// convertToSplitHandshakeTests to generate a handshaker hints variant. This
	// avoids repeating the -is-handshaker-supported and -handshaker-path logic.
	// (While not useful, the tests will still pass without a handshaker.)
	for _, protocol := range []protocol{tls, quic} {
		// If the signing payload is different, the handshake still completes
		// successfully. Different ALPN preferences will trigger a mismatch.
		testCases = append(testCases, testCase{
			name:               protocol.String() + "-HintMismatch-SignatureInput",
			testType:           serverTest,
			protocol:           protocol,
			skipSplitHandshake: true,
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				NextProtos: []string{"foo", "bar"},
			},
			flags: []string{
				"-allow-hint-mismatch",
				"-on-shim-select-alpn", "foo",
				"-on-handshaker-select-alpn", "bar",
			},
			expectations: connectionExpectations{
				nextProto:     "foo",
				nextProtoType: alpn,
			},
		})

		// The shim and handshaker may have different curve preferences.
		testCases = append(testCases, testCase{
			name:               protocol.String() + "-HintMismatch-KeyShare",
			testType:           serverTest,
			protocol:           protocol,
			skipSplitHandshake: true,
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				// Send both curves in the key share list, to avoid getting
				// mixed up with HelloRetryRequest.
				DefaultCurves: []CurveID{CurveX25519, CurveP256},
			},
			flags: []string{
				"-allow-hint-mismatch",
				"-on-shim-curves", strconv.Itoa(int(CurveX25519)),
				"-on-handshaker-curves", strconv.Itoa(int(CurveP256)),
			},
			expectations: connectionExpectations{
				curveID: CurveX25519,
			},
		})
		if protocol != quic {
			testCases = append(testCases, testCase{
				name:               protocol.String() + "-HintMismatch-ECDHE-Group",
				testType:           serverTest,
				protocol:           protocol,
				skipSplitHandshake: true,
				config: Config{
					MinVersion:    VersionTLS12,
					MaxVersion:    VersionTLS12,
					DefaultCurves: []CurveID{CurveX25519, CurveP256},
				},
				flags: []string{
					"-allow-hint-mismatch",
					"-on-shim-curves", strconv.Itoa(int(CurveX25519)),
					"-on-handshaker-curves", strconv.Itoa(int(CurveP256)),
				},
				expectations: connectionExpectations{
					curveID: CurveX25519,
				},
			})
		}

		// If the handshaker does HelloRetryRequest, it will omit most hints.
		// The shim should still work.
		testCases = append(testCases, testCase{
			name:               protocol.String() + "-HintMismatch-HandshakerHelloRetryRequest",
			testType:           serverTest,
			protocol:           protocol,
			skipSplitHandshake: true,
			config: Config{
				MinVersion:    VersionTLS13,
				MaxVersion:    VersionTLS13,
				DefaultCurves: []CurveID{CurveX25519},
			},
			flags: []string{
				"-allow-hint-mismatch",
				"-on-shim-curves", strconv.Itoa(int(CurveX25519)),
				"-on-handshaker-curves", strconv.Itoa(int(CurveP256)),
			},
			expectations: connectionExpectations{
				curveID: CurveX25519,
			},
		})

		// If the shim does HelloRetryRequest, the hints from the handshaker
		// will be ignored. This is not reported as a mismatch because hints
		// would not have helped the shim anyway.
		testCases = append(testCases, testCase{
			name:               protocol.String() + "-HintMismatch-ShimHelloRetryRequest",
			testType:           serverTest,
			protocol:           protocol,
			skipSplitHandshake: true,
			config: Config{
				MinVersion:    VersionTLS13,
				MaxVersion:    VersionTLS13,
				DefaultCurves: []CurveID{CurveX25519},
			},
			flags: []string{
				"-on-shim-curves", strconv.Itoa(int(CurveP256)),
				"-on-handshaker-curves", strconv.Itoa(int(CurveX25519)),
			},
			expectations: connectionExpectations{
				curveID: CurveP256,
			},
		})

		// The shim and handshaker may have different signature algorithm
		// preferences.
		testCases = append(testCases, testCase{
			name:               protocol.String() + "-HintMismatch-SignatureAlgorithm-TLS13",
			testType:           serverTest,
			protocol:           protocol,
			skipSplitHandshake: true,
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				VerifySignatureAlgorithms: []signatureAlgorithm{
					signatureRSAPSSWithSHA256,
					signatureRSAPSSWithSHA384,
				},
			},
			shimCertificate:       rsaCertificate.WithSignatureAlgorithms(signatureRSAPSSWithSHA256),
			handshakerCertificate: rsaCertificate.WithSignatureAlgorithms(signatureRSAPSSWithSHA384),
			flags:                 []string{"-allow-hint-mismatch"},
			expectations: connectionExpectations{
				peerSignatureAlgorithm: signatureRSAPSSWithSHA256,
			},
		})
		if protocol != quic {
			testCases = append(testCases, testCase{
				name:               protocol.String() + "-HintMismatch-SignatureAlgorithm-TLS12",
				testType:           serverTest,
				protocol:           protocol,
				skipSplitHandshake: true,
				config: Config{
					MinVersion: VersionTLS12,
					MaxVersion: VersionTLS12,
					VerifySignatureAlgorithms: []signatureAlgorithm{
						signatureRSAPSSWithSHA256,
						signatureRSAPSSWithSHA384,
					},
				},
				shimCertificate:       rsaCertificate.WithSignatureAlgorithms(signatureRSAPSSWithSHA256),
				handshakerCertificate: rsaCertificate.WithSignatureAlgorithms(signatureRSAPSSWithSHA384),
				flags:                 []string{"-allow-hint-mismatch"},
				expectations: connectionExpectations{
					peerSignatureAlgorithm: signatureRSAPSSWithSHA256,
				},
			})
		}

		// The shim and handshaker may use different certificates. In TLS 1.3,
		// the signature input includes the certificate, so we do not need to
		// explicitly check for a public key match. In TLS 1.2, it does not.
		ecdsaP256Certificate2 := generateSingleCertChain(nil, &channelIDKey)
		testCases = append(testCases, testCase{
			name:               protocol.String() + "-HintMismatch-Certificate-TLS13",
			testType:           serverTest,
			protocol:           protocol,
			skipSplitHandshake: true,
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
			},
			shimCertificate:       &ecdsaP256Certificate,
			handshakerCertificate: &ecdsaP256Certificate2,
			flags:                 []string{"-allow-hint-mismatch"},
			expectations: connectionExpectations{
				peerCertificate: &ecdsaP256Certificate,
			},
		})
		if protocol != quic {
			testCases = append(testCases, testCase{
				name:               protocol.String() + "-HintMismatch-Certificate-TLS12",
				testType:           serverTest,
				protocol:           protocol,
				skipSplitHandshake: true,
				config: Config{
					MinVersion: VersionTLS12,
					MaxVersion: VersionTLS12,
				},
				shimCertificate:       &ecdsaP256Certificate,
				handshakerCertificate: &ecdsaP256Certificate2,
				flags:                 []string{"-allow-hint-mismatch"},
				expectations: connectionExpectations{
					peerCertificate: &ecdsaP256Certificate,
				},
			})
		}

		// The shim and handshaker may disagree on whether resumption is allowed.
		// We run the first connection with tickets enabled, so the client is
		// issued a ticket, then disable tickets on the second connection.
		testCases = append(testCases, testCase{
			name:               protocol.String() + "-HintMismatch-NoTickets1-TLS13",
			testType:           serverTest,
			protocol:           protocol,
			skipSplitHandshake: true,
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
			},
			flags: []string{
				"-on-resume-allow-hint-mismatch",
				"-on-shim-on-resume-no-ticket",
			},
			resumeSession:        true,
			expectResumeRejected: true,
		})
		testCases = append(testCases, testCase{
			name:               protocol.String() + "-HintMismatch-NoTickets2-TLS13",
			testType:           serverTest,
			protocol:           protocol,
			skipSplitHandshake: true,
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
			},
			flags: []string{
				"-on-resume-allow-hint-mismatch",
				"-on-handshaker-on-resume-no-ticket",
			},
			resumeSession: true,
		})
		if protocol != quic {
			testCases = append(testCases, testCase{
				name:               protocol.String() + "-HintMismatch-NoTickets1-TLS12",
				testType:           serverTest,
				protocol:           protocol,
				skipSplitHandshake: true,
				config: Config{
					MinVersion: VersionTLS12,
					MaxVersion: VersionTLS12,
				},
				flags: []string{
					"-on-resume-allow-hint-mismatch",
					"-on-shim-on-resume-no-ticket",
				},
				resumeSession:        true,
				expectResumeRejected: true,
			})
			testCases = append(testCases, testCase{
				name:               protocol.String() + "-HintMismatch-NoTickets2-TLS12",
				testType:           serverTest,
				protocol:           protocol,
				skipSplitHandshake: true,
				config: Config{
					MinVersion: VersionTLS12,
					MaxVersion: VersionTLS12,
				},
				flags: []string{
					"-on-resume-allow-hint-mismatch",
					"-on-handshaker-on-resume-no-ticket",
				},
				resumeSession: true,
			})
		}

		// The shim and handshaker may disagree on whether to request a client
		// certificate.
		testCases = append(testCases, testCase{
			name:               protocol.String() + "-HintMismatch-CertificateRequest",
			testType:           serverTest,
			protocol:           protocol,
			skipSplitHandshake: true,
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				Credential: &rsaCertificate,
			},
			flags: []string{
				"-allow-hint-mismatch",
				"-on-shim-require-any-client-certificate",
			},
		})

		// The shim and handshaker may negotiate different versions altogether.
		if protocol != quic {
			testCases = append(testCases, testCase{
				name:               protocol.String() + "-HintMismatch-Version1",
				testType:           serverTest,
				protocol:           protocol,
				skipSplitHandshake: true,
				config: Config{
					MinVersion: VersionTLS12,
					MaxVersion: VersionTLS13,
				},
				flags: []string{
					"-allow-hint-mismatch",
					"-on-shim-max-version", strconv.Itoa(VersionTLS12),
					"-on-handshaker-max-version", strconv.Itoa(VersionTLS13),
				},
				expectations: connectionExpectations{
					version: VersionTLS12,
				},
			})
			testCases = append(testCases, testCase{
				name:               protocol.String() + "-HintMismatch-Version2",
				testType:           serverTest,
				protocol:           protocol,
				skipSplitHandshake: true,
				config: Config{
					MinVersion: VersionTLS12,
					MaxVersion: VersionTLS13,
				},
				flags: []string{
					"-allow-hint-mismatch",
					"-on-shim-max-version", strconv.Itoa(VersionTLS13),
					"-on-handshaker-max-version", strconv.Itoa(VersionTLS12),
				},
				expectations: connectionExpectations{
					version: VersionTLS13,
				},
			})
		}

		// The shim and handshaker may disagree on the certificate compression
		// algorithm, whether to enable certificate compression, or certificate
		// compression inputs.
		testCases = append(testCases, testCase{
			name:               protocol.String() + "-HintMismatch-CertificateCompression-ShimOnly",
			testType:           serverTest,
			protocol:           protocol,
			skipSplitHandshake: true,
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				CertCompressionAlgs: map[uint16]CertCompressionAlg{
					shrinkingCompressionAlgID: shrinkingCompression,
				},
				Bugs: ProtocolBugs{
					ExpectedCompressedCert: shrinkingCompressionAlgID,
				},
			},
			flags: []string{
				"-allow-hint-mismatch",
				"-on-shim-install-cert-compression-algs",
			},
		})
		testCases = append(testCases, testCase{
			name:               protocol.String() + "-HintMismatch-CertificateCompression-HandshakerOnly",
			testType:           serverTest,
			protocol:           protocol,
			skipSplitHandshake: true,
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				CertCompressionAlgs: map[uint16]CertCompressionAlg{
					shrinkingCompressionAlgID: shrinkingCompression,
				},
				Bugs: ProtocolBugs{
					ExpectUncompressedCert: true,
				},
			},
			flags: []string{
				"-allow-hint-mismatch",
				"-on-handshaker-install-cert-compression-algs",
			},
		})
		testCases = append(testCases, testCase{
			testType:           serverTest,
			name:               protocol.String() + "-HintMismatch-CertificateCompression-AlgorithmMismatch",
			protocol:           protocol,
			skipSplitHandshake: true,
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				CertCompressionAlgs: map[uint16]CertCompressionAlg{
					shrinkingCompressionAlgID: shrinkingCompression,
					expandingCompressionAlgID: expandingCompression,
				},
				Bugs: ProtocolBugs{
					// The shim's preferences should take effect.
					ExpectedCompressedCert: shrinkingCompressionAlgID,
				},
			},
			flags: []string{
				"-allow-hint-mismatch",
				"-on-shim-install-one-cert-compression-alg", strconv.Itoa(shrinkingCompressionAlgID),
				"-on-handshaker-install-one-cert-compression-alg", strconv.Itoa(expandingCompressionAlgID),
			},
		})
		testCases = append(testCases, testCase{
			testType:           serverTest,
			name:               protocol.String() + "-HintMismatch-CertificateCompression-InputMismatch",
			protocol:           protocol,
			skipSplitHandshake: true,
			config: Config{
				MinVersion: VersionTLS13,
				MaxVersion: VersionTLS13,
				CertCompressionAlgs: map[uint16]CertCompressionAlg{
					shrinkingCompressionAlgID: shrinkingCompression,
				},
				Bugs: ProtocolBugs{
					ExpectedCompressedCert: shrinkingCompressionAlgID,
				},
			},
			// Configure the shim and handshaker with different OCSP responses,
			// so the compression inputs do not match.
			shimCertificate:       rsaCertificate.WithOCSP(testOCSPResponse),
			handshakerCertificate: rsaCertificate.WithOCSP(testOCSPResponse2),
			flags: []string{
				"-allow-hint-mismatch",
				"-install-cert-compression-algs",
			},
			expectations: connectionExpectations{
				// The shim's configuration should take precendence.
				peerCertificate: rsaCertificate.WithOCSP(testOCSPResponse),
			},
		})

		// The shim and handshaker may disagree on cipher suite, to the point
		// that one selects RSA key exchange (no applicable hint) and the other
		// selects ECDHE_RSA (hints are useful).
		if protocol != quic {
			testCases = append(testCases, testCase{
				testType:           serverTest,
				name:               protocol.String() + "-HintMismatch-CipherMismatch1",
				protocol:           protocol,
				skipSplitHandshake: true,
				config: Config{
					MinVersion: VersionTLS12,
					MaxVersion: VersionTLS12,
				},
				flags: []string{
					"-allow-hint-mismatch",
					"-on-shim-cipher", "TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256",
					"-on-handshaker-cipher", "TLS_RSA_WITH_AES_128_GCM_SHA256",
				},
				expectations: connectionExpectations{
					cipher: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
				},
			})
			testCases = append(testCases, testCase{
				testType:           serverTest,
				name:               protocol.String() + "-HintMismatch-CipherMismatch2",
				protocol:           protocol,
				skipSplitHandshake: true,
				config: Config{
					MinVersion: VersionTLS12,
					MaxVersion: VersionTLS12,
				},
				flags: []string{
					// There is no need to pass -allow-hint-mismatch. The
					// handshaker will unnecessarily generate a signature hints.
					// This is not reported as a mismatch because hints would
					// not have helped the shim anyway.
					"-on-shim-cipher", "TLS_RSA_WITH_AES_128_GCM_SHA256",
					"-on-handshaker-cipher", "TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256",
				},
				expectations: connectionExpectations{
					cipher: TLS_RSA_WITH_AES_128_GCM_SHA256,
				},
			})
		}
	}
}

func addCompliancePolicyTests() {
	for _, protocol := range []protocol{tls, quic} {
		for _, suite := range testCipherSuites {
			var isFIPSCipherSuite bool
			switch suite.id {
			case TLS_AES_128_GCM_SHA256,
				TLS_AES_256_GCM_SHA384,
				TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
				TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
				TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
				TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256:
				isFIPSCipherSuite = true
			}

			var isWPACipherSuite bool
			switch suite.id {
			case TLS_AES_256_GCM_SHA384,
				TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
				TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384:
				isWPACipherSuite = true
			}

			var cert Credential
			if hasComponent(suite.name, "ECDSA") {
				cert = ecdsaP384Certificate
			} else {
				cert = rsaCertificate
			}

			maxVersion := uint16(VersionTLS13)
			if !isTLS13Suite(suite.name) {
				if protocol == quic {
					continue
				}
				maxVersion = VersionTLS12
			}

			policies := []struct {
				flag          string
				cipherSuiteOk bool
			}{
				{"-fips-202205", isFIPSCipherSuite},
				{"-wpa-202304", isWPACipherSuite},
			}

			for _, policy := range policies {
				testCases = append(testCases, testCase{
					testType: serverTest,
					protocol: protocol,
					name:     "Compliance" + policy.flag + "-" + protocol.String() + "-Server-" + suite.name,
					config: Config{
						MinVersion:   VersionTLS12,
						MaxVersion:   maxVersion,
						CipherSuites: []uint16{suite.id},
					},
					shimCertificate: &cert,
					flags: []string{
						policy.flag,
					},
					shouldFail: !policy.cipherSuiteOk,
				})

				testCases = append(testCases, testCase{
					testType: clientTest,
					protocol: protocol,
					name:     "Compliance" + policy.flag + "-" + protocol.String() + "-Client-" + suite.name,
					config: Config{
						MinVersion:   VersionTLS12,
						MaxVersion:   maxVersion,
						CipherSuites: []uint16{suite.id},
						Credential:   &cert,
					},
					flags: []string{
						policy.flag,
					},
					shouldFail: !policy.cipherSuiteOk,
				})
			}
		}

		// Check that a TLS 1.3 client won't accept ChaCha20 even if the server
		// picks it without it being in the client's cipher list.
		testCases = append(testCases, testCase{
			testType: clientTest,
			protocol: protocol,
			name:     "Compliance-fips202205-" + protocol.String() + "-Client-ReallyWontAcceptChaCha",
			config: Config{
				MinVersion: VersionTLS12,
				MaxVersion: maxVersion,
				Bugs: ProtocolBugs{
					SendCipherSuite: TLS_CHACHA20_POLY1305_SHA256,
				},
			},
			flags: []string{
				"-fips-202205",
			},
			shouldFail:    true,
			expectedError: ":WRONG_CIPHER_RETURNED:",
		})

		for _, curve := range testCurves {
			var isFIPSCurve bool
			switch curve.id {
			case CurveP256, CurveP384:
				isFIPSCurve = true
			}

			var isWPACurve bool
			switch curve.id {
			case CurveP384:
				isWPACurve = true
			}

			policies := []struct {
				flag    string
				curveOk bool
			}{
				{"-fips-202205", isFIPSCurve},
				{"-wpa-202304", isWPACurve},
			}

			for _, policy := range policies {
				testCases = append(testCases, testCase{
					testType: serverTest,
					protocol: protocol,
					name:     "Compliance" + policy.flag + "-" + protocol.String() + "-Server-" + curve.name,
					config: Config{
						MinVersion:       VersionTLS12,
						MaxVersion:       VersionTLS13,
						CurvePreferences: []CurveID{curve.id},
					},
					flags: []string{
						policy.flag,
					},
					shouldFail: !policy.curveOk,
				})

				testCases = append(testCases, testCase{
					testType: clientTest,
					protocol: protocol,
					name:     "Compliance" + policy.flag + "-" + protocol.String() + "-Client-" + curve.name,
					config: Config{
						MinVersion:       VersionTLS12,
						MaxVersion:       VersionTLS13,
						CurvePreferences: []CurveID{curve.id},
					},
					flags: []string{
						policy.flag,
					},
					shouldFail: !policy.curveOk,
				})
			}
		}

		for _, sigalg := range testSignatureAlgorithms {
			// The TLS 1.0 and TLS 1.1 default signature algorithm does not
			// apply to these tests.
			if sigalg.id == 0 {
				continue
			}

			var isFIPSSigAlg bool
			switch sigalg.id {
			case signatureRSAPKCS1WithSHA256,
				signatureRSAPKCS1WithSHA384,
				signatureRSAPKCS1WithSHA512,
				signatureECDSAWithP256AndSHA256,
				signatureECDSAWithP384AndSHA384,
				signatureRSAPSSWithSHA256,
				signatureRSAPSSWithSHA384,
				signatureRSAPSSWithSHA512:
				isFIPSSigAlg = true
			}

			var isWPASigAlg bool
			switch sigalg.id {
			case signatureRSAPKCS1WithSHA384,
				signatureRSAPKCS1WithSHA512,
				signatureECDSAWithP384AndSHA384,
				signatureRSAPSSWithSHA384,
				signatureRSAPSSWithSHA512:
				isWPASigAlg = true
			}

			if sigalg.curve == CurveP224 {
				// This can work in TLS 1.2, but not with TLS 1.3.
				// For consistency it's not permitted in FIPS mode.
				isFIPSSigAlg = false
			}

			maxVersion := uint16(VersionTLS13)
			if hasComponent(sigalg.name, "PKCS1") {
				if protocol == quic {
					continue
				}
				maxVersion = VersionTLS12
			}

			policies := []struct {
				flag     string
				sigAlgOk bool
			}{
				{"-fips-202205", isFIPSSigAlg},
				{"-wpa-202304", isWPASigAlg},
			}

			cert := sigalg.baseCert.WithSignatureAlgorithms(sigalg.id)
			for _, policy := range policies {
				testCases = append(testCases, testCase{
					testType: serverTest,
					protocol: protocol,
					name:     "Compliance" + policy.flag + "-" + protocol.String() + "-Server-" + sigalg.name,
					config: Config{
						MinVersion:                VersionTLS12,
						MaxVersion:                maxVersion,
						VerifySignatureAlgorithms: []signatureAlgorithm{sigalg.id},
					},
					// Use the base certificate. We wish to pick up the signature algorithm
					// preferences from the FIPS policy.
					shimCertificate: sigalg.baseCert,
					flags:           []string{policy.flag},
					shouldFail:      !policy.sigAlgOk,
				})

				testCases = append(testCases, testCase{
					testType: clientTest,
					protocol: protocol,
					name:     "Compliance" + policy.flag + "-" + protocol.String() + "-Client-" + sigalg.name,
					config: Config{
						MinVersion: VersionTLS12,
						MaxVersion: maxVersion,
						Credential: cert,
					},
					flags: []string{
						policy.flag,
					},
					shouldFail: !policy.sigAlgOk,
				})
			}
		}

		// AES-256-GCM is the most preferred.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     "Compliance-cnsa202407-" + protocol.String() + "-AES-256-preferred",
			config: Config{
				MinVersion:   VersionTLS13,
				MaxVersion:   VersionTLS13,
				CipherSuites: []uint16{TLS_CHACHA20_POLY1305_SHA256, TLS_AES_128_GCM_SHA256, TLS_AES_256_GCM_SHA384},
			},
			flags: []string{
				"-cnsa-202407",
			},
			expectations: connectionExpectations{cipher: TLS_AES_256_GCM_SHA384},
		})

		// AES-128-GCM is preferred over ChaCha20-Poly1305.
		testCases = append(testCases, testCase{
			testType: serverTest,
			protocol: protocol,
			name:     "Compliance-cnsa202407-" + protocol.String() + "-AES-128-preferred",
			config: Config{
				MinVersion:   VersionTLS13,
				MaxVersion:   VersionTLS13,
				CipherSuites: []uint16{TLS_CHACHA20_POLY1305_SHA256, TLS_AES_128_GCM_SHA256},
			},
			flags: []string{
				"-cnsa-202407",
			},
			expectations: connectionExpectations{cipher: TLS_AES_128_GCM_SHA256},
		})
	}
}

func canBeShimCertificate(c *Credential) bool {
	// Some options can only be set with the credentials API.
	return c.Type == CredentialTypeX509 && !c.MustMatchIssuer
}

func addCertificateSelectionTests() {
	// Combinatorially test each selection criteria at different versions,
	// protocols, and with the matching certificate before and after the
	// mismatching one.
	type certSelectTest struct {
		name          string
		testType      testType
		minVersion    uint16
		maxVersion    uint16
		config        Config
		match         *Credential
		mismatch      *Credential
		flags         []string
		expectedError string
	}
	certSelectTests := []certSelectTest{
		// TLS 1.0 through TLS 1.2 servers should incorporate TLS cipher suites
		// into certificate selection.
		{
			name:       "Server-CipherSuite-ECDHE_ECDSA",
			testType:   serverTest,
			maxVersion: VersionTLS12,
			config: Config{
				CipherSuites: []uint16{
					TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
				},
			},
			match:         &ecdsaP256Certificate,
			mismatch:      &rsaCertificate,
			expectedError: ":NO_SHARED_CIPHER:",
		},
		{
			name:       "Server-CipherSuite-ECDHE_RSA",
			testType:   serverTest,
			maxVersion: VersionTLS12,
			config: Config{
				CipherSuites: []uint16{
					TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
				},
			},
			match:         &rsaCertificate,
			mismatch:      &ecdsaP256Certificate,
			expectedError: ":NO_SHARED_CIPHER:",
		},
		{
			name:       "Server-CipherSuite-RSA",
			testType:   serverTest,
			maxVersion: VersionTLS12,
			config: Config{
				CipherSuites: []uint16{
					TLS_RSA_WITH_AES_128_CBC_SHA,
				},
			},
			match:         &rsaCertificate,
			mismatch:      &ecdsaP256Certificate,
			expectedError: ":NO_SHARED_CIPHER:",
		},

		// Ed25519 counts as ECDSA for purposes of cipher suite matching.
		{
			name:       "Server-CipherSuite-ECDHE_ECDSA-Ed25519",
			testType:   serverTest,
			minVersion: VersionTLS12,
			maxVersion: VersionTLS12,
			config: Config{
				CipherSuites: []uint16{
					TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
				},
			},
			match:         &ed25519Certificate,
			mismatch:      &rsaCertificate,
			expectedError: ":NO_SHARED_CIPHER:",
		},
		{
			name:       "Server-CipherSuite-ECDHE_RSA-Ed25519",
			testType:   serverTest,
			minVersion: VersionTLS12,
			maxVersion: VersionTLS12,
			config: Config{
				CipherSuites: []uint16{
					TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
				},
			},
			match:         &rsaCertificate,
			mismatch:      &ed25519Certificate,
			expectedError: ":NO_SHARED_CIPHER:",
		},

		// If there is no ECDHE curve match, ECDHE cipher suites are
		// disqualified in TLS 1.2 and below. This, in turn, impacts the
		// available cipher suites for each credential.
		{
			name:       "Server-CipherSuite-NoECDHE",
			testType:   serverTest,
			maxVersion: VersionTLS12,
			config: Config{
				CurvePreferences: []CurveID{CurveP256},
			},
			flags:         []string{"-curves", strconv.Itoa(int(CurveX25519))},
			match:         &rsaCertificate,
			mismatch:      &ecdsaP256Certificate,
			expectedError: ":NO_SHARED_CIPHER:",
		},

		// If the client offered a cipher that would allow a certificate, but it
		// wasn't one of the ones we configured, the certificate should be
		// skipped in favor of another one.
		{
			name:       "Server-CipherSuite-Prefs",
			testType:   serverTest,
			maxVersion: VersionTLS12,
			config: Config{
				CipherSuites: []uint16{
					TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
					TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
				},
			},
			flags:         []string{"-cipher", "TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA:TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA"},
			match:         &rsaCertificate,
			mismatch:      &ecdsaP256Certificate,
			expectedError: ":NO_SHARED_CIPHER:",
		},

		// TLS 1.0 through 1.2 servers should incorporate the curve list into
		// ECDSA certificate selection.
		{
			name:       "Server-Curve",
			testType:   serverTest,
			maxVersion: VersionTLS12,
			config: Config{
				CurvePreferences: []CurveID{CurveP256},
			},
			match:         &ecdsaP256Certificate,
			mismatch:      &ecdsaP384Certificate,
			expectedError: ":WRONG_CURVE:",
		},

		// TLS 1.3 servers ignore the curve list. ECDSA certificate selection is
		// solely determined by the signature algorithm list.
		{
			name:       "Server-IgnoreCurve",
			testType:   serverTest,
			minVersion: VersionTLS13,
			config: Config{
				CurvePreferences: []CurveID{CurveP256},
			},
			match: &ecdsaP384Certificate,
		},

		// TLS 1.2 servers also ignore the curve list for Ed25519. The signature
		// algorithm list is sufficient for Ed25519.
		{
			name:       "Server-IgnoreCurveEd25519",
			testType:   serverTest,
			minVersion: VersionTLS12,
			config: Config{
				CurvePreferences: []CurveID{CurveP256},
			},
			match: &ed25519Certificate,
		},

		// Without signature algorithm negotiation, Ed25519 is not usable in TLS
		// 1.1 and below.
		{
			name:       "Server-NoEd25519",
			testType:   serverTest,
			maxVersion: VersionTLS11,
			match:      &rsaCertificate,
			mismatch:   &ed25519Certificate,
		},

		// TLS 1.2 and up should incorporate the signature algorithm list into
		// certificate selection.
		{
			name:       "Server-SignatureAlgorithm",
			testType:   serverTest,
			minVersion: VersionTLS12,
			maxVersion: VersionTLS12,
			config: Config{
				VerifySignatureAlgorithms: []signatureAlgorithm{signatureECDSAWithP256AndSHA256},
				CipherSuites: []uint16{
					TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
					TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
				},
			},
			match:         &ecdsaP256Certificate,
			mismatch:      &rsaCertificate,
			expectedError: ":NO_SHARED_CIPHER:",
		},
		{
			name:       "Server-SignatureAlgorithm",
			testType:   serverTest,
			minVersion: VersionTLS13,
			config: Config{
				VerifySignatureAlgorithms: []signatureAlgorithm{signatureECDSAWithP256AndSHA256},
			},
			match:         &ecdsaP256Certificate,
			mismatch:      &rsaCertificate,
			expectedError: ":NO_COMMON_SIGNATURE_ALGORITHMS:",
		},

		// TLS 1.2's use of the signature algorithm list only disables the
		// signing-based algorithms. If an RSA key exchange cipher suite is
		// eligible, that is fine. (This is not a realistic configuration,
		// however. No one would configure RSA before ECDSA.)
		{
			name:       "Server-SignatureAlgorithmImpactsECDHEOnly",
			testType:   serverTest,
			minVersion: VersionTLS12,
			maxVersion: VersionTLS12,
			config: Config{
				VerifySignatureAlgorithms: []signatureAlgorithm{signatureECDSAWithP256AndSHA256},
				CipherSuites: []uint16{
					TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
					TLS_RSA_WITH_AES_128_CBC_SHA,
				},
			},
			match: &rsaCertificate,
		},

		// TLS 1.3's use of the signature algorithm looks at the ECDSA curve
		// embedded in the signature algorithm.
		{
			name:       "Server-SignatureAlgorithmECDSACurve",
			testType:   serverTest,
			minVersion: VersionTLS13,
			config: Config{
				VerifySignatureAlgorithms: []signatureAlgorithm{signatureECDSAWithP256AndSHA256},
			},
			match:         &ecdsaP256Certificate,
			mismatch:      &ecdsaP384Certificate,
			expectedError: ":NO_COMMON_SIGNATURE_ALGORITHMS:",
		},

		// TLS 1.2's use does not.
		{
			name:       "Server-SignatureAlgorithmECDSACurve",
			testType:   serverTest,
			minVersion: VersionTLS12,
			maxVersion: VersionTLS12,
			config: Config{
				VerifySignatureAlgorithms: []signatureAlgorithm{signatureECDSAWithP256AndSHA256},
			},
			match: &ecdsaP384Certificate,
		},

		// TLS 1.0 and 1.1 do not look at the signature algorithm.
		{
			name:       "Server-IgnoreSignatureAlgorithm",
			testType:   serverTest,
			maxVersion: VersionTLS11,
			config: Config{
				VerifySignatureAlgorithms: []signatureAlgorithm{signatureECDSAWithP256AndSHA256},
			},
			match: &rsaCertificate,
		},

		// Signature algorithm matches take preferences on the keys into
		// consideration.
		{
			name:       "Server-SignatureAlgorithmKeyPrefs",
			testType:   serverTest,
			minVersion: VersionTLS12,
			maxVersion: VersionTLS12,
			config: Config{
				VerifySignatureAlgorithms: []signatureAlgorithm{signatureRSAPSSWithSHA256},
				CipherSuites:              []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
			},
			match:         rsaChainCertificate.WithSignatureAlgorithms(signatureRSAPSSWithSHA256),
			mismatch:      rsaCertificate.WithSignatureAlgorithms(signatureRSAPSSWithSHA384),
			expectedError: ":NO_SHARED_CIPHER:",
		},
		{
			name:       "Server-SignatureAlgorithmKeyPrefs",
			testType:   serverTest,
			minVersion: VersionTLS13,
			config: Config{
				VerifySignatureAlgorithms: []signatureAlgorithm{signatureRSAPSSWithSHA256},
			},
			match:         rsaChainCertificate.WithSignatureAlgorithms(signatureRSAPSSWithSHA256),
			mismatch:      rsaCertificate.WithSignatureAlgorithms(signatureRSAPSSWithSHA384),
			expectedError: ":NO_COMMON_SIGNATURE_ALGORITHMS:",
		},

		// TLS 1.2 clients and below check the certificate against the old
		// client certificate types field.
		{
			name:       "Client-ClientCertificateTypes-RSA",
			testType:   clientTest,
			maxVersion: VersionTLS12,
			config: Config{
				ClientAuth:             RequestClientCert,
				ClientCertificateTypes: []uint8{CertTypeRSASign},
			},
			match:         &rsaCertificate,
			mismatch:      &ecdsaP256Certificate,
			expectedError: ":UNKNOWN_CERTIFICATE_TYPE:",
		},
		{
			name:       "Client-ClientCertificateTypes-ECDSA",
			testType:   clientTest,
			maxVersion: VersionTLS12,
			config: Config{
				ClientAuth:             RequestClientCert,
				ClientCertificateTypes: []uint8{CertTypeECDSASign},
			},
			match:         &ecdsaP256Certificate,
			mismatch:      &rsaCertificate,
			expectedError: ":UNKNOWN_CERTIFICATE_TYPE:",
		},

		// Ed25519 is considered ECDSA for purposes of client certificate types.
		{
			name:       "Client-ClientCertificateTypes-RSA-Ed25519",
			testType:   clientTest,
			minVersion: VersionTLS12,
			maxVersion: VersionTLS12,
			config: Config{
				ClientAuth:             RequestClientCert,
				ClientCertificateTypes: []uint8{CertTypeRSASign},
			},
			match:         &rsaCertificate,
			mismatch:      &ed25519Certificate,
			expectedError: ":UNKNOWN_CERTIFICATE_TYPE:",
		},
		{
			name:       "Client-ClientCertificateTypes-ECDSA-Ed25519",
			testType:   clientTest,
			minVersion: VersionTLS12,
			maxVersion: VersionTLS12,
			config: Config{
				ClientAuth:             RequestClientCert,
				ClientCertificateTypes: []uint8{CertTypeECDSASign},
			},
			match:         &ed25519Certificate,
			mismatch:      &rsaCertificate,
			expectedError: ":UNKNOWN_CERTIFICATE_TYPE:",
		},

		// TLS 1.2 and up should incorporate the signature algorithm list into
		// certificate selection. (There is no signature algorithm list to look
		// at in TLS 1.0 and 1.1.)
		{
			name:       "Client-SignatureAlgorithm",
			testType:   clientTest,
			minVersion: VersionTLS12,
			config: Config{
				ClientAuth:                RequestClientCert,
				VerifySignatureAlgorithms: []signatureAlgorithm{signatureECDSAWithP256AndSHA256},
			},
			match:         &ecdsaP256Certificate,
			mismatch:      &rsaCertificate,
			expectedError: ":NO_COMMON_SIGNATURE_ALGORITHMS:",
		},

		// TLS 1.3's use of the signature algorithm looks at the ECDSA curve
		// embedded in the signature algorithm.
		{
			name:       "Client-SignatureAlgorithmECDSACurve",
			testType:   clientTest,
			minVersion: VersionTLS13,
			config: Config{
				ClientAuth:                RequestClientCert,
				VerifySignatureAlgorithms: []signatureAlgorithm{signatureECDSAWithP256AndSHA256},
			},
			match:         &ecdsaP256Certificate,
			mismatch:      &ecdsaP384Certificate,
			expectedError: ":NO_COMMON_SIGNATURE_ALGORITHMS:",
		},

		// TLS 1.2's use does not. It is not possible to determine what ECDSA
		// curves are allowed by the server.
		{
			name:       "Client-SignatureAlgorithmECDSACurve",
			testType:   clientTest,
			minVersion: VersionTLS12,
			maxVersion: VersionTLS12,
			config: Config{
				ClientAuth:                RequestClientCert,
				VerifySignatureAlgorithms: []signatureAlgorithm{signatureECDSAWithP256AndSHA256},
			},
			match: &ecdsaP384Certificate,
		},

		// Signature algorithm matches take preferences on the keys into
		// consideration.
		{
			name:       "Client-SignatureAlgorithmKeyPrefs",
			testType:   clientTest,
			minVersion: VersionTLS12,
			config: Config{
				ClientAuth:                RequestClientCert,
				VerifySignatureAlgorithms: []signatureAlgorithm{signatureRSAPSSWithSHA256},
			},
			match:         rsaChainCertificate.WithSignatureAlgorithms(signatureRSAPSSWithSHA256),
			mismatch:      rsaCertificate.WithSignatureAlgorithms(signatureRSAPSSWithSHA384),
			expectedError: ":NO_COMMON_SIGNATURE_ALGORITHMS:",
		},

		// By default, certificate selection does not take issuers
		// into account.
		{
			name:     "Client-DontCheckIssuer",
			testType: clientTest,
			config: Config{
				ClientAuth: RequestClientCert,
				ClientCAs:  makeCertPoolFromRoots(&rsaChainCertificate, &ecdsaP384Certificate),
			},
			match: &ecdsaP256Certificate,
		},
		{
			name:     "Server-DontCheckIssuer",
			testType: serverTest,
			config: Config{
				RootCAs:     makeCertPoolFromRoots(&rsaChainCertificate, &ecdsaP384Certificate),
				SendRootCAs: true,
			},
			match: &ecdsaP256Certificate,
		},

		// If requested, certificate selection will match against the
		// requested issuers.
		{
			name:     "Client-CheckIssuer",
			testType: clientTest,
			config: Config{
				ClientAuth: RequestClientCert,
				ClientCAs:  makeCertPoolFromRoots(&rsaChainCertificate, &ecdsaP384Certificate),
			},
			match:         rsaChainCertificate.WithMustMatchIssuer(true),
			mismatch:      ecdsaP256Certificate.WithMustMatchIssuer(true),
			expectedError: ":NO_MATCHING_ISSUER:",
		},
		{
			name:     "Server-CheckIssuer",
			testType: serverTest,
			config: Config{
				RootCAs:     makeCertPoolFromRoots(&rsaChainCertificate, &ecdsaP384Certificate),
				SendRootCAs: true,
			},
			match:         rsaChainCertificate.WithMustMatchIssuer(true),
			mismatch:      ecdsaP256Certificate.WithMustMatchIssuer(true),
			expectedError: ":NO_MATCHING_ISSUER:",
		},
	}

	for _, protocol := range []protocol{tls, dtls} {
		for _, vers := range allVersions(protocol) {
			suffix := fmt.Sprintf("%s-%s", protocol, vers)

			// Test that the credential list is interpreted in preference order,
			// with the default credential, if any, at the end.
			testCases = append(testCases, testCase{
				name:     fmt.Sprintf("CertificateSelection-Client-PreferenceOrder-%s", suffix),
				testType: clientTest,
				protocol: protocol,
				config: Config{
					MinVersion: vers.version,
					MaxVersion: vers.version,
					ClientAuth: RequestClientCert,
				},
				shimCredentials: []*Credential{&ecdsaP256Certificate, &ecdsaP384Certificate},
				shimCertificate: &rsaCertificate,
				flags:           []string{"-expect-selected-credential", "0"},
				expectations:    connectionExpectations{peerCertificate: &ecdsaP256Certificate},
			})
			testCases = append(testCases, testCase{
				name:     fmt.Sprintf("CertificateSelection-Server-PreferenceOrder-%s", suffix),
				testType: serverTest,
				protocol: protocol,
				config: Config{
					MinVersion: vers.version,
					MaxVersion: vers.version,
				},
				shimCredentials: []*Credential{&ecdsaP256Certificate, &ecdsaP384Certificate},
				shimCertificate: &rsaCertificate,
				flags:           []string{"-expect-selected-credential", "0"},
				expectations:    connectionExpectations{peerCertificate: &ecdsaP256Certificate},
			})

			// Test that the selected credential contributes the certificate chain, OCSP response,
			// and SCT list.
			testCases = append(testCases, testCase{
				name:     fmt.Sprintf("CertificateSelection-Server-OCSP-SCT-%s", suffix),
				testType: serverTest,
				protocol: protocol,
				config: Config{
					MinVersion: vers.version,
					MaxVersion: vers.version,
					// Configure enough options so that, at all TLS versions, only an RSA
					// certificate will be accepted.
					CipherSuites: []uint16{
						TLS_AES_128_GCM_SHA256,
						TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
						TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
					},
					VerifySignatureAlgorithms: []signatureAlgorithm{signatureRSAPSSWithSHA256},
				},
				shimCredentials: []*Credential{
					ecdsaP256Certificate.WithOCSP(testOCSPResponse2).WithSCTList(testSCTList2),
					rsaChainCertificate.WithOCSP(testOCSPResponse).WithSCTList(testSCTList),
				},
				shimCertificate: ecdsaP384Certificate.WithOCSP(testOCSPResponse2).WithSCTList(testSCTList2),
				flags:           []string{"-expect-selected-credential", "1"},
				expectations: connectionExpectations{
					peerCertificate: rsaChainCertificate.WithOCSP(testOCSPResponse).WithSCTList(testSCTList),
				},
			})

			// Test that the credentials API works asynchronously. This tests both deferring the
			// configuration to the certificate callback, and using a custom, async private key.
			testCases = append(testCases, testCase{
				name:     fmt.Sprintf("CertificateSelection-Client-Async-%s", suffix),
				testType: clientTest,
				protocol: protocol,
				config: Config{
					MinVersion: vers.version,
					MaxVersion: vers.version,
					ClientAuth: RequestClientCert,
				},
				shimCredentials: []*Credential{&ecdsaP256Certificate},
				shimCertificate: &rsaCertificate,
				flags:           []string{"-async", "-expect-selected-credential", "0"},
				expectations:    connectionExpectations{peerCertificate: &ecdsaP256Certificate},
			})
			testCases = append(testCases, testCase{
				name:     fmt.Sprintf("CertificateSelection-Server-Async-%s", suffix),
				testType: serverTest,
				protocol: protocol,
				config: Config{
					MinVersion: vers.version,
					MaxVersion: vers.version,
				},
				shimCredentials: []*Credential{&ecdsaP256Certificate},
				shimCertificate: &rsaCertificate,
				flags:           []string{"-async", "-expect-selected-credential", "0"},
				expectations:    connectionExpectations{peerCertificate: &ecdsaP256Certificate},
			})

			for _, test := range certSelectTests {
				if test.minVersion != 0 && vers.version < test.minVersion {
					continue
				}
				if test.maxVersion != 0 && vers.version > test.maxVersion {
					continue
				}

				config := test.config
				config.MinVersion = vers.version
				config.MaxVersion = vers.version

				// If the mismatch field is omitted, this is a positive test,
				// just to confirm that the selection logic does not block a
				// particular certificate.
				if test.mismatch == nil {
					testCases = append(testCases, testCase{
						name:            fmt.Sprintf("CertificateSelection-%s-%s", test.name, suffix),
						protocol:        protocol,
						testType:        test.testType,
						config:          config,
						shimCredentials: []*Credential{test.match},
						flags:           append([]string{"-expect-selected-credential", "0"}, test.flags...),
						expectations:    connectionExpectations{peerCertificate: test.match},
					})
					continue
				}

				testCases = append(testCases, testCase{
					name:            fmt.Sprintf("CertificateSelection-%s-MatchFirst-%s", test.name, suffix),
					protocol:        protocol,
					testType:        test.testType,
					config:          config,
					shimCredentials: []*Credential{test.match, test.mismatch},
					flags:           append([]string{"-expect-selected-credential", "0"}, test.flags...),
					expectations:    connectionExpectations{peerCertificate: test.match},
				})
				testCases = append(testCases, testCase{
					name:            fmt.Sprintf("CertificateSelection-%s-MatchSecond-%s", test.name, suffix),
					protocol:        protocol,
					testType:        test.testType,
					config:          config,
					shimCredentials: []*Credential{test.mismatch, test.match},
					flags:           append([]string{"-expect-selected-credential", "1"}, test.flags...),
					expectations:    connectionExpectations{peerCertificate: test.match},
				})
				if canBeShimCertificate(test.match) {
					testCases = append(testCases, testCase{
						name:            fmt.Sprintf("CertificateSelection-%s-MatchDefault-%s", test.name, suffix),
						protocol:        protocol,
						testType:        test.testType,
						config:          config,
						shimCredentials: []*Credential{test.mismatch},
						shimCertificate: test.match,
						flags:           append([]string{"-expect-selected-credential", "-1"}, test.flags...),
						expectations:    connectionExpectations{peerCertificate: test.match},
					})
				}
				testCases = append(testCases, testCase{
					name:               fmt.Sprintf("CertificateSelection-%s-MatchNone-%s", test.name, suffix),
					protocol:           protocol,
					testType:           test.testType,
					config:             config,
					shimCredentials:    []*Credential{test.mismatch, test.mismatch, test.mismatch},
					flags:              test.flags,
					shouldFail:         true,
					expectedLocalError: "remote error: handshake failure",
					expectedError:      test.expectedError,
				})
			}
		}
	}
}

func addKeyUpdateTests() {
	// TLS tests.
	testCases = append(testCases, testCase{
		name: "KeyUpdate-ToClient",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		sendKeyUpdates:   10,
		keyUpdateRequest: keyUpdateNotRequested,
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "KeyUpdate-ToServer",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		sendKeyUpdates:   10,
		keyUpdateRequest: keyUpdateNotRequested,
	})
	testCases = append(testCases, testCase{
		name: "KeyUpdate-FromClient",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		expectUnsolicitedKeyUpdate: true,
		flags:                      []string{"-key-update"},
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		name:     "KeyUpdate-FromServer",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		expectUnsolicitedKeyUpdate: true,
		flags:                      []string{"-key-update"},
	})
	testCases = append(testCases, testCase{
		name: "KeyUpdate-InvalidRequestMode",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		sendKeyUpdates:   1,
		keyUpdateRequest: 42,
		shouldFail:       true,
		expectedError:    ":DECODE_ERROR:",
	})
	testCases = append(testCases, testCase{
		// Test that shim responds to KeyUpdate requests.
		name: "KeyUpdate-Requested",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				RejectUnsolicitedKeyUpdate: true,
			},
		},
		// Test the shim receiving many KeyUpdates in a row.
		sendKeyUpdates:   5,
		messageCount:     5,
		keyUpdateRequest: keyUpdateRequested,
	})
	testCases = append(testCases, testCase{
		// Test that shim responds to KeyUpdate requests if peer's KeyUpdate is
		// discovered while a write is pending.
		name: "KeyUpdate-Requested-UnfinishedWrite",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				RejectUnsolicitedKeyUpdate: true,
			},
		},
		// Test the shim receiving many KeyUpdates in a row.
		sendKeyUpdates:          5,
		messageCount:            5,
		keyUpdateRequest:        keyUpdateRequested,
		readWithUnfinishedWrite: true,
		flags:                   []string{"-async"},
	})

	// DTLS tests.
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "KeyUpdate-ToClient-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		// Send many KeyUpdates to make sure record reassembly can handle it.
		sendKeyUpdates:   10,
		keyUpdateRequest: keyUpdateNotRequested,
	})
	testCases = append(testCases, testCase{
		protocol: dtls,
		testType: serverTest,
		name:     "KeyUpdate-ToServer-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		sendKeyUpdates:   10,
		keyUpdateRequest: keyUpdateNotRequested,
	})

	// Test that the shim accounts for packet loss when processing KeyUpdate.
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "KeyUpdate-ToClient-PacketLoss-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
					if next[0].Type != typeKeyUpdate {
						c.WriteFlight(next)
						return
					}

					// Send the KeyUpdate. The shim should ACK it.
					c.WriteFlight(next)
					ackTimeout := timeouts[0] / 4
					c.AdvanceClock(ackTimeout)
					c.ReadACK(c.InEpoch())

					// The shim should continue reading data at the old epoch.
					// The ACK may not have come through.
					msg := []byte("test")
					c.WriteAppData(c.OutEpoch()-1, msg)
					c.ReadAppData(c.InEpoch(), expectedReply(msg))

					// Re-send KeyUpdate. The shim should ACK it again. The ACK
					// may not have come through.
					c.WriteFlight(next)
					c.AdvanceClock(ackTimeout)
					c.ReadACK(c.InEpoch())

					// The shim should be able to read data at the new epoch.
					c.WriteAppData(c.OutEpoch(), msg)
					c.ReadAppData(c.InEpoch(), expectedReply(msg))

					// The shim continues to accept application data at the old
					// epoch, for a period of time.
					c.WriteAppData(c.OutEpoch()-1, msg)
					c.ReadAppData(c.InEpoch(), expectedReply(msg))

					// It will even ACK the retransmission, though it knows the
					// shim has seen the ACK.
					c.WriteFlight(next)
					c.AdvanceClock(ackTimeout)
					c.ReadACK(c.InEpoch())

					// After some time has passed, the shim will discard the old
					// epoch. The following writes should be ignored.
					c.AdvanceClock(dtlsPrevEpochExpiration)
					f := next[0].Fragment(0, len(next[0].Data))
					f.ShouldDiscard = true
					c.WriteFragments([]DTLSFragment{f})
					c.WriteAppData(c.OutEpoch()-1, msg)
				},
			},
		},
		sendKeyUpdates:   10,
		keyUpdateRequest: keyUpdateNotRequested,
		flags:            []string{"-async"},
	})

	// In DTLS, we KeyUpdate before read, rather than write, because the
	// KeyUpdate will not be applied before the shim reads the ACK.
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "KeyUpdate-FromClient-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		shimSendsKeyUpdateBeforeRead: true,
		// Perform several message exchanges to update keys several times.
		messageCount: 10,
	})
	testCases = append(testCases, testCase{
		protocol: dtls,
		testType: serverTest,
		name:     "KeyUpdate-FromServer-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		shimSendsKeyUpdateBeforeRead: true,
		// Perform several message exchanges to update keys several times.
		messageCount: 10,
		// Avoid NewSessionTicket messages getting in the way of ReadKeyUpdate.
		flags: []string{"-no-ticket"},
	})

	// If the shim has a pending unACKed flight, it defers sending KeyUpdate.
	// BoringSSL does not support multiple outgoing flights at once.
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "KeyUpdate-DeferredSend-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
			// Request a client certificate, so the shim has more to send.
			ClientAuth: RequireAnyClientCert,
			Bugs: ProtocolBugs{
				MaxPacketLength: 512,
				ACKFlightDTLS: func(c *DTLSController, prev, received []DTLSMessage, records []DTLSRecordNumberInfo) {
					if received[len(received)-1].Type != typeFinished {
						c.WriteACK(c.OutEpoch(), records)
						return
					}

					// This test relies on the Finished flight being multiple
					// records.
					if len(records) <= 1 {
						panic("shim sent Finished flight in one record")
					}

					// Before ACKing Finished, do some rounds of exchanging
					// application data. Although the shim has already scheduled
					// KeyUpdate, it should not send the KeyUpdate until it gets
					// an ACK. (If it sent KeyUpdate, ReadAppData would report
					// an unexpected record.)
					msg := []byte("test")
					for i := 0; i < 10; i++ {
						c.WriteAppData(c.OutEpoch(), msg)
						c.ReadAppData(c.InEpoch(), expectedReply(msg))
					}

					// ACK some of the Finished flight, but not all of it.
					c.WriteACK(c.OutEpoch(), records[:1])

					// The shim continues to defer KeyUpdate.
					for i := 0; i < 10; i++ {
						c.WriteAppData(c.OutEpoch(), msg)
						c.ReadAppData(c.InEpoch(), expectedReply(msg))
					}

					// ACK the remainder.
					c.WriteACK(c.OutEpoch(), records[1:])

					// The shim should now send KeyUpdate. Return to the test
					// harness, which will look for it.
				},
			},
		},
		shimCertificate:              &rsaChainCertificate,
		shimSendsKeyUpdateBeforeRead: true,
		flags:                        []string{"-mtu", "512"},
	})

	// The shim should not switch keys until it receives an ACK.
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "KeyUpdate-WaitForACK-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				MaxPacketLength: 512,
				ACKFlightDTLS: func(c *DTLSController, prev, received []DTLSMessage, records []DTLSRecordNumberInfo) {
					if received[0].Type != typeKeyUpdate {
						c.WriteACK(c.OutEpoch(), records)
						return
					}

					// Make the shim send application data. We have not yet
					// ACKed KeyUpdate, so the shim should send at the previous
					// epoch. Through each of these rounds, the shim will also
					// try to KeyUpdate again. These calls will be suppressed
					// because there is still an outstanding KeyUpdate.
					msg := []byte("test")
					for i := 0; i < 10; i++ {
						c.WriteAppData(c.OutEpoch(), msg)
						c.ReadAppData(c.InEpoch()-1, expectedReply(msg))
					}

					// ACK the KeyUpdate. Ideally we'd test a partial ACK, but
					// BoringSSL's minimum MTU is such that KeyUpdate always
					// fits in one record.
					c.WriteACK(c.OutEpoch(), records)

					// The shim should now send at the new epoch. Return to the
					// test harness, which will enforce this.
				},
			},
		},
		shimSendsKeyUpdateBeforeRead: true,
	})

	// Test that shim responds to KeyUpdate requests.
	fixKeyUpdateReply := func(c *DTLSController, prev, received []DTLSMessage, records []DTLSRecordNumberInfo) {
		c.WriteACK(c.OutEpoch(), records)
		if received[0].Type != typeKeyUpdate {
			return
		}
		// This works around an awkward testing mismatch. The test
		// harness expects the shim to immediately change keys, but
		// the shim writes app data before seeing the ACK. The app
		// data will be sent at the previous epoch. Consume this and
		// prime the shim to resend its reply at the new epoch.
		msg := makeTestMessage(int(received[0].Sequence)-2, 32)
		c.ReadAppData(c.InEpoch()-1, expectedReply(msg))
		c.WriteAppData(c.OutEpoch(), msg)
	}
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "KeyUpdate-Requested-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				RejectUnsolicitedKeyUpdate: true,
				ACKFlightDTLS:              fixKeyUpdateReply,
			},
		},
		// Test the shim receiving many KeyUpdates in a row. They will be
		// combined into one reply KeyUpdate.
		sendKeyUpdates:   5,
		messageLen:       32,
		messageCount:     5,
		keyUpdateRequest: keyUpdateRequested,
	})

	mergeNewSessionTicketAndKeyUpdate := func(f WriteFlightFunc) WriteFlightFunc {
		return func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
			// Send NewSessionTicket and the first KeyUpdate all together.
			if next[0].Type == typeKeyUpdate {
				panic("key update should have been merged into NewSessionTicket")
			}
			if next[0].Type != typeNewSessionTicket {
				c.WriteFlight(next)
				return
			}
			if next[0].Type == typeNewSessionTicket && next[len(next)-1].Type != typeKeyUpdate {
				c.MergeIntoNextFlight()
				return
			}

			f(c, prev, received, next, records)
		}
	}

	// Test that the shim does not process KeyUpdate until it has processed all
	// preceding messages.
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "KeyUpdate-ProcessInOrder-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				WriteFlightDTLS: mergeNewSessionTicketAndKeyUpdate(func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
					// Write the KeyUpdate. The shim should buffer and ACK it.
					keyUpdate := next[len(next)-1]
					c.WriteFlight([]DTLSMessage{keyUpdate})
					ackTimeout := timeouts[0] / 4
					c.AdvanceClock(ackTimeout)
					c.ReadACK(c.InEpoch())

					// The shim should not process KeyUpdate yet. It should not
					// read from the new epoch.
					msg1, msg2 := []byte("aaaa"), []byte("bbbb")
					c.WriteAppData(c.OutEpoch(), msg1)
					c.AdvanceClock(0) // Check there are no messages.

					// It can read from the old epoch, however.
					c.WriteAppData(c.OutEpoch()-1, msg2)
					c.ReadAppData(c.InEpoch(), expectedReply(msg2))

					// Write the rest of the flight.
					c.WriteFlight(next[:len(next)-1])
					c.AdvanceClock(ackTimeout)
					c.ReadACK(c.InEpoch())

					// Now the new epoch is functional.
					c.WriteAppData(c.OutEpoch(), msg1)
					c.ReadAppData(c.InEpoch(), expectedReply(msg1))
				}),
			},
		},
		sendKeyUpdates:   1,
		keyUpdateRequest: keyUpdateNotRequested,
		flags:            []string{"-async"},
	})

	// Messages after a KeyUpdate are not allowed.
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "KeyUpdate-ExtraMessage-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				WriteFlightDTLS: mergeNewSessionTicketAndKeyUpdate(func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
					extra := next[0]
					extra.Sequence = next[len(next)-1].Sequence + 1
					next = append(slices.Clip(next), extra)
					c.WriteFlight(next)
				}),
			},
		},
		sendKeyUpdates:     1,
		keyUpdateRequest:   keyUpdateNotRequested,
		shouldFail:         true,
		expectedError:      ":EXCESS_HANDSHAKE_DATA:",
		expectedLocalError: "remote error: unexpected message",
	})
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "KeyUpdate-ExtraMessageBuffered-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				WriteFlightDTLS: mergeNewSessionTicketAndKeyUpdate(func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
					// Send the extra message first. The shim should accept and
					// buffer it.
					extra := next[0]
					extra.Sequence = next[len(next)-1].Sequence + 1
					c.WriteFlight([]DTLSMessage{extra})

					// Now send the flight, including a KeyUpdate. The shim
					// should now notice the extra message and reject.
					c.WriteFlight(next)
				}),
			},
		},
		sendKeyUpdates:     1,
		keyUpdateRequest:   keyUpdateNotRequested,
		shouldFail:         true,
		expectedError:      ":EXCESS_HANDSHAKE_DATA:",
		expectedLocalError: "remote error: unexpected message",
	})

	// Test KeyUpdate overflow conditions. Both the epoch number and the message
	// number may overflow, in either the read or write direction.

	// When the sender is the client, the first KeyUpdate is message 2 at epoch
	// 3, so the epoch number overflows first.
	const maxClientKeyUpdates = 0xffff - 3

	// Test that the shim, as a server, rejects KeyUpdates at epoch 0xffff. RFC
	// 9147 does not prescribe this limit, but we enforce it. See
	// https://mailarchive.ietf.org/arch/msg/tls/6y8wTv8Q_IPM-PCcbCAmDOYg6bM/
	// and https://www.rfc-editor.org/errata/eid8050
	writeFlightKeyUpdate := func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
		if next[0].Type == typeKeyUpdate {
			// Exchange some data to avoid tripping KeyUpdate DoS limits.
			msg := []byte("test")
			c.WriteAppData(c.OutEpoch()-1, msg)
			c.ReadAppData(c.InEpoch(), expectedReply(msg))
		}
		c.WriteFlight(next)
	}
	testCases = append(testCases, testCase{
		testType: serverTest,
		protocol: dtls,
		name:     "KeyUpdate-MaxReadEpoch-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				AllowEpochOverflow: true,
				WriteFlightDTLS:    writeFlightKeyUpdate,
			},
		},
		// Avoid the NewSessionTicket messages interfering with the callback.
		flags:            []string{"-no-ticket"},
		sendKeyUpdates:   maxClientKeyUpdates,
		keyUpdateRequest: keyUpdateNotRequested,
	})
	testCases = append(testCases, testCase{
		testType: serverTest,
		protocol: dtls,
		name:     "KeyUpdate-ReadEpochOverflow-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				AllowEpochOverflow: true,
				WriteFlightDTLS:    writeFlightKeyUpdate,
			},
		},
		// Avoid the NewSessionTicket messages interfering with the callback.
		flags:              []string{"-no-ticket"},
		sendKeyUpdates:     maxClientKeyUpdates + 1,
		keyUpdateRequest:   keyUpdateNotRequested,
		shouldFail:         true,
		expectedError:      ":TOO_MANY_KEY_UPDATES:",
		expectedLocalError: "remote error: unexpected message",
	})

	// Test that the shim, as a client, notices its epoch overflow condition
	// when asked to send too many KeyUpdates. The shim sends KeyUpdate before
	// every read, including reading connection close, so the number of
	// KeyUpdates is one more than the message count.
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "KeyUpdate-MaxWriteEpoch-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		shimSendsKeyUpdateBeforeRead: true,
		messageCount:                 maxClientKeyUpdates - 1,
	})
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "KeyUpdate-WriteEpochOverflow-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				// The shim does not notice the overflow until immediately after
				// sending KeyUpdate, so tolerate the overflow on the runner.
				AllowEpochOverflow: true,
			},
		},
		shimSendsKeyUpdateBeforeRead: true,
		messageCount:                 maxClientKeyUpdates,
		shouldFail:                   true,
		expectedError:                ":TOO_MANY_KEY_UPDATES:",
	})

	// When the sender is a server that doesn't send tickets, the first
	// KeyUpdate is message 5 (SH, EE, C, CV, Fin) at epoch 3, so the message
	// number overflows first.
	const maxServerKeyUpdates = 0xffff - 5

	// Test that the shim, as a client, does not allow the value to wraparound.
	testCases = append(testCases, testCase{
		protocol: dtls,
		name:     "KeyUpdate-ReadMessageOverflow-DTLS",
		config: Config{
			MaxVersion:             VersionTLS13,
			SessionTicketsDisabled: true,
			Bugs: ProtocolBugs{
				AllowEpochOverflow: true,
				WriteFlightDTLS: func(c *DTLSController, prev, received, next []DTLSMessage, records []DTLSRecordNumberInfo) {
					writeFlightKeyUpdate(c, prev, received, next, records)
					if next[0].Type == typeKeyUpdate && next[0].Sequence == 0xffff {
						// At this point, the shim has accepted message 0xffff.
						// Check the shim does not now accept message 0 as the
						// current message. Test this by sending a garbage
						// message 0. A shim that overflows and processes the
						// message will notice the syntax error. A shim that
						// correctly interprets this as an old message will drop
						// the record and simply ACK it.
						//
						// We do this rather than send a valid KeyUpdate because
						// the shim will keep the old epoch active and drop
						// decryption failures. Looking for the lack of an error
						// is more straightforward.
						c.WriteFlight([]DTLSMessage{{Epoch: c.OutEpoch(), Sequence: 0, Type: typeKeyUpdate, Data: []byte("INVALID")}})
						c.ExpectNextTimeout(timeouts[0] / 4)
						c.AdvanceClock(timeouts[0] / 4)
						c.ReadACK(c.InEpoch())
					}
				},
			},
		},
		sendKeyUpdates:   maxServerKeyUpdates + 1,
		keyUpdateRequest: keyUpdateNotRequested,
		flags:            []string{"-async", "-expect-no-session"},
	})

	// Test that the shim, as a server, notices its message overflow condition,
	// when asked to send too many KeyUpdates.
	testCases = append(testCases, testCase{
		protocol: dtls,
		testType: serverTest,
		name:     "KeyUpdate-MaxWriteMessage-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		shimSendsKeyUpdateBeforeRead: true,
		messageCount:                 maxServerKeyUpdates,
		// Avoid NewSessionTicket messages getting in the way of ReadKeyUpdate.
		flags: []string{"-no-ticket"},
	})
	testCases = append(testCases, testCase{
		protocol: dtls,
		testType: serverTest,
		name:     "KeyUpdate-WriteMessageOverflow-DTLS",
		config: Config{
			MaxVersion: VersionTLS13,
		},
		shimSendsKeyUpdateBeforeRead: true,
		messageCount:                 maxServerKeyUpdates + 1,
		shouldFail:                   true,
		expectedError:                ":overflow:",
		// Avoid NewSessionTicket messages getting in the way of ReadKeyUpdate.
		flags: []string{"-no-ticket"},
	})
}

func addPAKETests() {
	spakeCredential := Credential{
		Type:         CredentialTypeSPAKE2PlusV1,
		PAKEContext:  []byte("context"),
		PAKEClientID: []byte("client"),
		PAKEServerID: []byte("server"),
		PAKEPassword: []byte("password"),
	}

	spakeWrongClientID := spakeCredential
	spakeWrongClientID.PAKEClientID = []byte("wrong")

	spakeWrongServerID := spakeCredential
	spakeWrongServerID.PAKEServerID = []byte("wrong")

	spakeWrongPassword := spakeCredential
	spakeWrongPassword.PAKEPassword = []byte("wrong")

	spakeWrongRole := spakeCredential
	spakeWrongRole.WrongPAKERole = true

	spakeWrongCodepoint := spakeCredential
	spakeWrongCodepoint.OverridePAKECodepoint = 1234

	testCases = append(testCases, testCase{
		name:     "PAKE-No-Server-Support",
		testType: serverTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeCredential,
		},
		shouldFail:    true,
		expectedError: ":MISSING_KEY_SHARE:",
	})
	testCases = append(testCases, testCase{
		name:     "PAKE-Server",
		testType: serverTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeCredential,
			Bugs: ProtocolBugs{
				// We do not currently support resumption with PAKE, so PAKE
				// servers should not issue session tickets.
				ExpectNoNewSessionTicket: true,
			},
		},
		shimCredentials: []*Credential{&spakeCredential},
	})
	testCases = append(testCases, testCase{
		// Send a ClientHello with the wrong PAKE client ID.
		name:     "PAKE-Server-WrongClientID",
		testType: serverTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeWrongClientID,
		},
		shimCredentials:    []*Credential{&spakeCredential},
		shouldFail:         true,
		expectedError:      ":PEER_PAKE_MISMATCH:",
		expectedLocalError: "remote error: handshake failure",
	})
	testCases = append(testCases, testCase{
		// Send a ClientHello with the wrong PAKE server ID.
		name:     "PAKE-Server-WrongServerID",
		testType: serverTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeWrongServerID,
		},
		shimCredentials:    []*Credential{&spakeCredential},
		shouldFail:         true,
		expectedError:      ":PEER_PAKE_MISMATCH:",
		expectedLocalError: "remote error: handshake failure",
	})
	testCases = append(testCases, testCase{
		// Send a ClientHello with the wrong PAKE codepoint.
		name:     "PAKE-Server-WrongCodepoint",
		testType: serverTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeWrongCodepoint,
		},
		shimCredentials:    []*Credential{&spakeCredential},
		shouldFail:         true,
		expectedError:      ":PEER_PAKE_MISMATCH:",
		expectedLocalError: "remote error: handshake failure",
	})
	testCases = append(testCases, testCase{
		// A server configured with a mix of PAKE and non-PAKE
		// credentials will select the first that matches what the
		// client offered. In doing so, it should skip unsupported
		// PAKE algorithms.
		name:     "PAKE-Server-MultiplePAKEs",
		testType: serverTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeCredential,
			Bugs: ProtocolBugs{
				OfferExtraPAKEs: []uint16{1, 2, 3, 4, 5},
			},
		},
		shimCredentials: []*Credential{&spakeWrongClientID, &spakeWrongServerID, &spakeWrongRole, &spakeCredential, &rsaCertificate},
		flags:           []string{"-expect-selected-credential", "3"},
	})
	testCases = append(testCases, testCase{
		// A server configured with a certificate credential before a
		// PAKE credential will consider the certificate credential first.
		name:     "PAKE-Server-CertificateBeforePAKE",
		testType: serverTest,
		config: Config{
			MinVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				// Pretend to offer a matching PAKE share, but expect the
				// shim to select the credential first and negotiate a
				// normal handshake.
				OfferExtraPAKEClientID: spakeCredential.PAKEClientID,
				OfferExtraPAKEServerID: spakeCredential.PAKEServerID,
				OfferExtraPAKEs:        []uint16{spakeID},
			},
		},
		shimCredentials: []*Credential{&rsaCertificate, &spakeCredential},
		flags:           []string{"-expect-selected-credential", "0"},
	})
	testCases = append(testCases, testCase{
		// A server configured with just a PAKE credential should reject normal
		// clients.
		name:     "PAKE-Server-NormalClient",
		testType: serverTest,
		config: Config{
			MinVersion: VersionTLS13,
		},
		shimCredentials:    []*Credential{&spakeCredential},
		shouldFail:         true,
		expectedError:      ":PEER_PAKE_MISMATCH:",
		expectedLocalError: "remote error: handshake failure",
	})
	testCases = append(testCases, testCase{
		// ... and TLS 1.2 clients.
		name:     "PAKE-Server-NormalTLS12Client",
		testType: serverTest,
		config: Config{
			MinVersion: VersionTLS12,
			MaxVersion: VersionTLS12,
		},
		shimCredentials:    []*Credential{&spakeCredential},
		shouldFail:         true,
		expectedError:      ":NO_SHARED_CIPHER:",
		expectedLocalError: "remote error: handshake failure",
	})
	testCases = append(testCases, testCase{
		// ... but you can configure a server with both PAKE and certificate-based
		// SSL_CREDENTIALs and that works.
		name:     "PAKE-ServerWithCertsToo-NormalClient",
		testType: serverTest,
		config: Config{
			MinVersion: VersionTLS13,
		},
		shimCredentials: []*Credential{&spakeCredential, &rsaCertificate},
		flags:           []string{"-expect-selected-credential", "1"},
	})
	testCases = append(testCases, testCase{
		// ... and for older clients.
		name:     "PAKE-ServerWithCertsToo-NormalTLS12Client",
		testType: serverTest,
		config: Config{
			MinVersion: VersionTLS12,
			MaxVersion: VersionTLS12,
		},
		shimCredentials: []*Credential{&spakeCredential, &rsaCertificate},
		flags:           []string{"-expect-selected-credential", "1"},
	})
	testCases = append(testCases, testCase{
		name:     "PAKE-Client",
		testType: clientTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeCredential,
			Bugs: ProtocolBugs{
				CheckClientHello: func(c *clientHelloMsg) error {
					// PAKE connections don't use the key_share / supported_groups mechanism.
					if c.hasKeyShares {
						return errors.New("unexpected key_share extension")
					}
					if len(c.supportedCurves) != 0 {
						return errors.New("unexpected supported_groups extension")
					}
					// PAKE connections don't use signature algorithms.
					if len(c.signatureAlgorithms) != 0 {
						return errors.New("unexpected signature_algorithms extension")
					}
					// We don't support resumption with PAKEs.
					if len(c.pskKEModes) != 0 {
						return errors.New("unexpected psk_key_exchange_modes extension")
					}
					return nil
				},
			},
		},
		shimCredentials: []*Credential{&spakeCredential},
	})
	testCases = append(testCases, testCase{
		// Although there is no reason to request new key shares, the PAKE
		// client should handle cookie requests.
		name:     "PAKE-Client-HRRCookie",
		testType: clientTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeCredential,
			Bugs: ProtocolBugs{
				SendHelloRetryRequestCookie: []byte("cookie"),
			},
		},
		shimCredentials: []*Credential{&spakeCredential},
	})
	testCases = append(testCases, testCase{
		// A PAKE client will not offer key shares, so the client should
		// reject a HelloRetryRequest requesting a different key share.
		name:     "PAKE-Client-HRRKeyShare",
		testType: clientTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeCredential,
			Bugs: ProtocolBugs{
				SendHelloRetryRequestCurve: CurveX25519,
			},
		},
		shimCredentials:    []*Credential{&spakeCredential},
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_EXTENSION:",
		expectedLocalError: "remote error: unsupported extension",
	})
	testCases = append(testCases, testCase{
		// A server cannot reply with an HRR asking for a PAKE if the client didn't
		// offer a PAKE in the ClientHello.
		name:     "PAKE-NormalClient-PAKEInHRR",
		testType: clientTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeCredential,
			Bugs: ProtocolBugs{
				AlwaysSendHelloRetryRequest: true,
				SendPAKEInHelloRetryRequest: true,
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_EXTENSION:",
	})
	testCases = append(testCases, testCase{
		// A PAKE client should not accept an empty ServerHello.
		name:     "PAKE-Client-EmptyServerHello",
		testType: clientTest,
		config: Config{
			MinVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				// Trigger an empty ServerHello by making a normal server skip
				// the key_share extension.
				MissingKeyShare: true,
			},
		},
		shimCredentials: []*Credential{&spakeCredential},
		shouldFail:      true,
		expectedError:   ":MISSING_EXTENSION:",
	})
	testCases = append(testCases, testCase{
		// A PAKE client should not accept a key_share ServerHello.
		name:     "PAKE-Client-KeyShareServerHello",
		testType: clientTest,
		config: Config{
			MinVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				// Trigger a key_share ServerHello by making a normal server
				// skip the HelloRetryRequest it would otherwise send in
				// response to the shim's key_share-less ClientHello.
				SkipHelloRetryRequest: true,
				// Ignore the client's lack of supported_groups.
				IgnorePeerCurvePreferences: true,
			},
		},
		shimCredentials: []*Credential{&spakeCredential},
		shouldFail:      true,
		expectedError:   ":UNEXPECTED_EXTENSION:",
	})
	testCases = append(testCases, testCase{
		// A PAKE client should not accept a TLS 1.2 ServerHello.
		name:     "PAKE-Client-TLS12ServerHello",
		testType: clientTest,
		config: Config{
			MinVersion: VersionTLS12,
			MaxVersion: VersionTLS12,
		},
		shimCredentials: []*Credential{&spakeCredential},
		shouldFail:      true,
		expectedError:   ":UNSUPPORTED_PROTOCOL:",
	})
	testCases = append(testCases, testCase{
		// A server cannot send the PAKE extension to a non-PAKE client.
		name:     "PAKE-NormalClient-UnsolicitedPAKEInServerHello",
		testType: clientTest,
		config: Config{
			Bugs: ProtocolBugs{
				UnsolicitedPAKE: spakeID,
			},
		},
		shouldFail:    true,
		expectedError: ":UNEXPECTED_EXTENSION:",
	})
	testCases = append(testCases, testCase{
		// A server cannot reply with a PAKE that the client did not offer.
		name:     "PAKE-Client-WrongPAKEInServerHello",
		testType: clientTest,
		config: Config{
			Bugs: ProtocolBugs{
				UnsolicitedPAKE: 1234,
			},
		},
		shimCredentials: []*Credential{&spakeCredential},
		shouldFail:      true,
		expectedError:   ":DECODE_ERROR:",
	})
	testCases = append(testCases, testCase{
		name:     "PAKE-Extension-Duplicate",
		testType: serverTest,
		config: Config{
			MinVersion: VersionTLS13,
			Bugs: ProtocolBugs{
				OfferExtraPAKEClientID: []byte("client"),
				OfferExtraPAKEServerID: []byte("server"),
				OfferExtraPAKEs:        []uint16{1234, 1234},
			},
		},
		shouldFail:    true,
		expectedError: ":ERROR_PARSING_EXTENSION:",
	})
	testCases = append(testCases, testCase{
		// If the client sees a server with a wrong password, it should
		// reject the confirmV value in the ServerHello.
		name:     "PAKE-Client-WrongPassword",
		testType: clientTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeWrongPassword,
		},
		shimCredentials: []*Credential{&spakeCredential},
		shouldFail:      true,
		expectedError:   ":DECODE_ERROR:",
	})
	testCases = append(testCases, testCase{
		name:     "PAKE-Client-Truncate",
		testType: clientTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeCredential,
			Bugs: ProtocolBugs{
				TruncatePAKEMessage: true,
			},
		},
		shimCredentials: []*Credential{&spakeCredential},
		shouldFail:      true,
		expectedError:   ":DECODE_ERROR:",
	})
	testCases = append(testCases, testCase{
		name:     "PAKE-Server-Truncate",
		testType: serverTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeCredential,
			Bugs: ProtocolBugs{
				TruncatePAKEMessage: true,
			},
		},
		shimCredentials:    []*Credential{&spakeCredential},
		shouldFail:         true,
		expectedError:      ":DECODE_ERROR:",
		expectedLocalError: "remote error: illegal parameter",
	})
	testCases = append(testCases, testCase{
		// Servers may not send CertificateRequest in a PAKE handshake.
		name:     "PAKE-Client-UnexpectedCertificateRequest",
		testType: clientTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeCredential,
			ClientAuth: RequireAnyClientCert,
			Bugs: ProtocolBugs{
				AlwaysSendCertificateRequest: true,
			},
		},
		shimCredentials:    []*Credential{&spakeCredential},
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_MESSAGE:",
		expectedLocalError: "remote error: unexpected message",
	})
	testCases = append(testCases, testCase{
		// Servers may not send Certificate in a PAKE handshake.
		name:     "PAKE-Client-UnexpectedCertificate",
		testType: clientTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeCredential,
			Bugs: ProtocolBugs{
				AlwaysSendCertificate:    true,
				UseCertificateCredential: &rsaCertificate,
				// Ignore the client's lack of signature_algorithms.
				IgnorePeerSignatureAlgorithmPreferences: true,
			},
		},
		shimCredentials:    []*Credential{&spakeCredential},
		shouldFail:         true,
		expectedError:      ":UNEXPECTED_MESSAGE:",
		expectedLocalError: "remote error: unexpected message",
	})
	testCases = append(testCases, testCase{
		// If a server is configured to request client certificates, it should
		// still not do so when negotiating a PAKE.
		name:     "PAKE-Server-DoNotRequestClientCertificate",
		testType: serverTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeCredential,
		},
		shimCredentials: []*Credential{&spakeCredential, &rsaCertificate},
		flags:           []string{"-require-any-client-certificate"},
	})
	testCases = append(testCases, testCase{
		// Clients should ignore server PAKE credentials.
		name:     "PAKE-Client-WrongRole",
		testType: clientTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeCredential,
		},
		shimCredentials: []*Credential{&spakeWrongRole},
		shouldFail:      true,
		// The shim will send a non-PAKE ClientHello.
		expectedLocalError: "tls: client not configured with PAKE",
	})
	testCases = append(testCases, testCase{
		// Servers should ignore client PAKE credentials.
		name:     "PAKE-Server-WrongRole",
		testType: serverTest,
		config: Config{
			MinVersion: VersionTLS13,
			Credential: &spakeCredential,
		},
		shimCredentials: []*Credential{&spakeWrongRole},
		shouldFail:      true,
		// The shim will fail the handshake because it has no usable credentials
		// available.
		expectedError:      ":UNKNOWN_CERTIFICATE_TYPE:",
		expectedLocalError: "remote error: handshake failure",
	})
	testCases = append(testCases, testCase{
		// On the client, we only support a single PAKE credential.
		name:            "PAKE-Client-MultiplePAKEs",
		testType:        clientTest,
		shimCredentials: []*Credential{&spakeCredential, &spakeWrongPassword},
		shouldFail:      true,
		expectedError:   ":UNSUPPORTED_CREDENTIAL_LIST:",
	})
	testCases = append(testCases, testCase{
		// On the client, we only support a single PAKE credential.
		name:            "PAKE-Client-PAKEAndCertificate",
		testType:        clientTest,
		shimCredentials: []*Credential{&spakeCredential, &rsaCertificate},
		shouldFail:      true,
		expectedError:   ":UNSUPPORTED_CREDENTIAL_LIST:",
	})
	testCases = append(testCases, testCase{
		// We currently do not support resumption with PAKE. Even if configured
		// with a session, the client should not offer the session with PAKEs.
		name:     "PAKE-Client-NoResume",
		testType: clientTest,
		// Make two connections. For the first connection, just establish a
		// session without PAKE, to pick up a session.
		config: Config{
			Credential: &rsaCertificate,
		},
		// For the second connection, use SPAKE.
		resumeSession: true,
		resumeConfig: &Config{
			Credential: &spakeCredential,
			Bugs: ProtocolBugs{
				// Check that the ClientHello does not offer a session, even
				// though one was configured.
				ExpectNoTLS13PSK: true,
				// Respond with an unsolicted PSK extension in ServerHello, to
				// check that the client rejects it.
				AlwaysSelectPSKIdentity: true,
			},
		},
		resumeShimCredentials: []*Credential{&spakeCredential},
		shouldFail:            true,
		expectedError:         ":UNEXPECTED_EXTENSION:",
	})
}

func worker(dispatcher *shimDispatcher, statusChan chan statusMsg, c chan *testCase, shimPath string, wg *sync.WaitGroup) {
	defer wg.Done()

	for test := range c {
		var err error

		if *mallocTest >= 0 {
			for mallocNumToFail := int64(*mallocTest); ; mallocNumToFail++ {
				statusChan <- statusMsg{test: test, statusType: statusStarted}
				if err = runTest(dispatcher, statusChan, test, shimPath, mallocNumToFail); err != errMoreMallocs {
					if err != nil {
						fmt.Printf("\n\nmalloc test failed at %d: %s\n", mallocNumToFail, err)
					}
					break
				}
			}
		} else if *repeatUntilFailure {
			for err == nil {
				statusChan <- statusMsg{test: test, statusType: statusStarted}
				err = runTest(dispatcher, statusChan, test, shimPath, -1)
			}
		} else {
			statusChan <- statusMsg{test: test, statusType: statusStarted}
			err = runTest(dispatcher, statusChan, test, shimPath, -1)
		}
		statusChan <- statusMsg{test: test, statusType: statusDone, err: err}
	}
}

type statusType int

const (
	statusStarted statusType = iota
	statusShimStarted
	statusDone
)

type statusMsg struct {
	test       *testCase
	statusType statusType
	pid        int
	err        error
}

func statusPrinter(doneChan chan *testresult.Results, statusChan chan statusMsg, total int) {
	var started, done, failed, unimplemented, lineLen int

	testOutput := testresult.NewResults()
	for msg := range statusChan {
		if !*pipe {
			// Erase the previous status line.
			var erase string
			for i := 0; i < lineLen; i++ {
				erase += "\b \b"
			}
			fmt.Print(erase)
		}

		if msg.statusType == statusStarted {
			started++
		} else if msg.statusType == statusDone {
			done++

			if msg.err != nil {
				if msg.err == errUnimplemented {
					if *pipe {
						// Print each test instead of a status line.
						fmt.Printf("UNIMPLEMENTED (%s)\n", msg.test.name)
					}
					unimplemented++
					if *allowUnimplemented {
						testOutput.AddSkip(msg.test.name)
					} else {
						testOutput.AddResult(msg.test.name, "SKIP", nil)
					}
				} else {
					fmt.Printf("FAILED (%s)\n%s\n", msg.test.name, msg.err)
					failed++
					testOutput.AddResult(msg.test.name, "FAIL", msg.err)
				}
			} else {
				if *pipe {
					// Print each test instead of a status line.
					fmt.Printf("PASSED (%s)\n", msg.test.name)
				}
				testOutput.AddResult(msg.test.name, "PASS", nil)
			}
		}

		if !*pipe {
			// Print a new status line.
			line := fmt.Sprintf("%d/%d/%d/%d/%d", failed, unimplemented, done, started, total)
			if msg.statusType == statusShimStarted && *waitForDebugger {
				// Note -wait-for-debugger limits the test to one worker,
				// otherwise some output would be skipped.
				line += fmt.Sprintf(" (%s: attach to process %d to continue)", msg.test.name, msg.pid)
			}
			lineLen = len(line)
			os.Stdout.WriteString(line)
		}
	}

	doneChan <- testOutput
}

func match(oneOfPatternIfAny []string, noneOfPattern []string, candidate string) (matched bool, err error) {
	matched = len(oneOfPatternIfAny) == 0

	var didMatch bool
	for _, pattern := range oneOfPatternIfAny {
		didMatch, err = filepath.Match(pattern, candidate)
		if err != nil {
			return false, err
		}

		matched = didMatch || matched
	}

	for _, pattern := range noneOfPattern {
		didMatch, err = filepath.Match(pattern, candidate)
		if err != nil {
			return false, err
		}

		matched = !didMatch && matched
	}

	return matched, nil
}

func checkTests() {
	for _, test := range testCases {
		if !test.shouldFail && (len(test.expectedError) > 0 || len(test.expectedLocalError) > 0) {
			panic("Error expected without shouldFail in " + test.name)
		}

		if test.expectResumeRejected && !test.resumeSession {
			panic("expectResumeRejected without resumeSession in " + test.name)
		}

		if !test.skipVersionNameCheck {
			for _, ver := range tlsVersions {
				if !strings.Contains("-"+test.name+"-", "-"+ver.name+"-") {
					continue
				}

				found := test.config.MaxVersion == ver.version || test.config.MinVersion == ver.version || test.expectations.version == ver.version
				if test.resumeConfig != nil {
					found = found || test.resumeConfig.MaxVersion == ver.version || test.resumeConfig.MinVersion == ver.version
				}
				if test.resumeExpectations != nil {
					found = found || test.resumeExpectations.version == ver.version
				}
				shimFlag := ver.shimFlag(test.protocol)
				for _, flag := range test.flags {
					if flag == shimFlag {
						found = true
						break
					}
				}
				if !found {
					panic(fmt.Sprintf("The name of test %q suggests that it's version specific, but the test does not reference %s", test.name, ver.name))
				}
			}
		}

		for _, protocol := range []protocol{tls, dtls, quic} {
			if strings.Contains("-"+test.name+"-", "-"+protocol.String()+"-") && test.protocol != protocol {
				panic(fmt.Sprintf("The name of test %q suggests that it tests %q, but the test does not reference it", test.name, protocol))
			}
		}
	}
}

func main() {
	flag.Parse()
	var err error
	if tmpDir, err = os.MkdirTemp("", "testing-certs"); err != nil {
		fmt.Fprintf(os.Stderr, "failed to make temporary directory: %s", err)
		os.Exit(1)
	}
	defer os.RemoveAll(tmpDir)
	initKeys()
	initCertificates()

	if len(*shimConfigFile) != 0 {
		encoded, err := os.ReadFile(*shimConfigFile)
		if err != nil {
			fmt.Fprintf(os.Stderr, "Couldn't read config file %q: %s\n", *shimConfigFile, err)
			os.Exit(1)
		}

		if err := json.Unmarshal(encoded, &shimConfig); err != nil {
			fmt.Fprintf(os.Stderr, "Couldn't decode config file %q: %s\n", *shimConfigFile, err)
			os.Exit(1)
		}
	}

	if shimConfig.AllCurves == nil {
		for _, curve := range testCurves {
			shimConfig.AllCurves = append(shimConfig.AllCurves, int(curve.id))
		}
	}

	addBasicTests()
	addCipherSuiteTests()
	addBadECDSASignatureTests()
	addCBCPaddingTests()
	addCBCSplittingTests()
	addClientAuthTests()
	addDDoSCallbackTests()
	addVersionNegotiationTests()
	addMinimumVersionTests()
	addExtensionTests()
	addResumptionVersionTests()
	addExtendedMasterSecretTests()
	addRenegotiationTests()
	addDTLSReplayTests()
	addSignatureAlgorithmTests()
	addDTLSRetransmitTests()
	addDTLSReorderTests()
	addExportKeyingMaterialTests()
	addExportTrafficSecretsTests()
	addTLSUniqueTests()
	addCustomExtensionTests()
	addRSAClientKeyExchangeTests()
	addCurveTests()
	addSessionTicketTests()
	addTLS13RecordTests()
	addAllStateMachineCoverageTests()
	addChangeCipherSpecTests()
	addEndOfFlightTests()
	addWrongMessageTypeTests()
	addTrailingMessageDataTests()
	addTLS13HandshakeTests()
	addTLS13CipherPreferenceTests()
	addPeekTests()
	addRecordVersionTests()
	addCertificateTests()
	addRetainOnlySHA256ClientCertTests()
	addECDSAKeyUsageTests()
	addRSAKeyUsageTests()
	addExtraHandshakeTests()
	addOmitExtensionsTests()
	addCertCompressionTests()
	addJDK11WorkaroundTests()
	addDelegatedCredentialTests()
	addEncryptedClientHelloTests()
	addHintMismatchTests()
	addCompliancePolicyTests()
	addCertificateSelectionTests()
	addKeyUpdateTests()
	addPAKETests()

	toAppend, err := convertToSplitHandshakeTests(testCases)
	if err != nil {
		fmt.Fprintf(os.Stderr, "Error making split handshake tests: %s", err)
		os.Exit(1)
	}
	testCases = append(testCases, toAppend...)

	checkTests()

	dispatcher, err := newShimDispatcher()
	if err != nil {
		fmt.Fprintf(os.Stderr, "Error opening socket: %s", err)
		os.Exit(1)
	}
	defer dispatcher.Close()

	numWorkers := *numWorkersFlag
	if useDebugger() {
		numWorkers = 1
	}

	statusChan := make(chan statusMsg, numWorkers)
	testChan := make(chan *testCase, numWorkers)
	doneChan := make(chan *testresult.Results)

	go statusPrinter(doneChan, statusChan, len(testCases))

	var wg sync.WaitGroup
	for i := 0; i < numWorkers; i++ {
		wg.Add(1)
		go worker(dispatcher, statusChan, testChan, *shimPath, &wg)
	}

	var oneOfPatternIfAny, noneOfPattern []string
	if len(*testToRun) > 0 {
		oneOfPatternIfAny = strings.Split(*testToRun, ";")
	}
	if len(*skipTest) > 0 {
		noneOfPattern = strings.Split(*skipTest, ";")
	}

	shardIndex, shardTotal, err := getSharding()
	if err != nil {
		fmt.Fprintln(os.Stderr, err)
		os.Exit(1)
	}

	if shardTotal > 0 {
		fmt.Printf("This is shard %d of 0..%d (inclusive)\n", shardIndex, shardTotal-1)
	}

	var foundTest bool
	for i := range testCases {
		if shardTotal > 0 && i%shardTotal != shardIndex {
			continue
		}

		matched, err := match(oneOfPatternIfAny, noneOfPattern, testCases[i].name)
		if err != nil {
			fmt.Fprintf(os.Stderr, "Error matching pattern: %s\n", err)
			os.Exit(1)
		}

		if !*includeDisabled {
			for pattern := range shimConfig.DisabledTests {
				isDisabled, err := filepath.Match(pattern, testCases[i].name)
				if err != nil {
					fmt.Fprintf(os.Stderr, "Error matching pattern %q from config file: %s\n", pattern, err)
					os.Exit(1)
				}

				if isDisabled {
					matched = false
					break
				}
			}
		}

		if matched {
			if foundTest && *useRR {
				fmt.Fprintf(os.Stderr, "Too many matching tests. Only one test can run when RR is enabled.\n")
				os.Exit(1)
			}

			foundTest = true
			testChan <- &testCases[i]

			// Only run one test if repeating until failure.
			if *repeatUntilFailure {
				break
			}
		}
	}

	if !foundTest && shardTotal == 0 {
		fmt.Fprintf(os.Stderr, "No tests run\n")
		os.Exit(1)
	}

	close(testChan)
	wg.Wait()
	close(statusChan)
	testOutput := <-doneChan

	fmt.Printf("\n")

	if *jsonOutput != "" {
		if err := testOutput.WriteToFile(*jsonOutput); err != nil {
			fmt.Fprintf(os.Stderr, "Error: %s\n", err)
		}
	}

	if *useRR {
		fmt.Println("RR trace recorded. Replay with `rr replay`.")
	}

	if !testOutput.HasUnexpectedResults() {
		os.Exit(1)
	}
}