// 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.

#include <limits.h>

#include <algorithm>
#include <functional>
#include <initializer_list>
#include <iterator>
#include <memory>
#include <string>
#include <string_view>
#include <utility>
#include <vector>

#include <gtest/gtest.h>

#include <openssl/asn1.h>
#include <openssl/bio.h>
#include <openssl/bytestring.h>
#include <openssl/conf.h>
#include <openssl/crypto.h>
#include <openssl/curve25519.h>
#include <openssl/digest.h>
#include <openssl/err.h>
#include <openssl/evp.h>
#include <openssl/mldsa.h>
#include <openssl/nid.h>
#include <openssl/obj.h>
#include <openssl/pem.h>
#include <openssl/pool.h>
#include <openssl/span.h>
#include <openssl/x509.h>

#include "../internal.h"
#include "../test/der_trailing_data.h"
#include "../test/file_util.h"
#include "../test/test_data.h"
#include "../test/test_util.h"
#include "internal.h"

#if defined(OPENSSL_THREADS)
#include <thread>
#endif


BSSL_NAMESPACE_BEGIN
namespace {

static const char kCrossSigningRootPEM[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

static const char kRootCAPEM[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

static const char kRootCrossSignedPEM[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

static const char kIntermediatePEM[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

static const char kIntermediateSelfSignedPEM[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

static const char kLeafPEM[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

static const char kLeafNoKeyUsagePEM[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

static const char kForgeryPEM[] = R"(
-----BEGIN CERTIFICATE-----
MIICZzCCAdCgAwIBAgIIdTlMzQoKkeMwDQYJKoZIhvcNAQELBQAwNzEaMBgGA1UE
ChMRQm9yaW5nU1NMIFRFU1RJTkcxGTAXBgNVBAMTEGV2aWwuZXhhbXBsZS5jb20w
IBcNMTUwMTAxMDAwMDAwWhgPMjEwMDAxMDEwMDAwMDBaMDoxGjAYBgNVBAoTEUJv
cmluZ1NTTCBURVNUSU5HMRwwGgYDVQQDExNmb3JnZXJ5LmV4YW1wbGUuY29tMIGf
MA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDADTwruBQZGb7Ay6s9HiYv5d1lwtEy
xQdA2Sy8Rn8uA20Q4KgqwVY7wzIZ+z5Butrsmwb70gdG1XU+yRaDeE7XVoW6jSpm
0sw35/5vJbTcL4THEFbnX0OPZnvpuZDFUkvVtq5kxpDWsVyM24G8EEq7kPih3Sa3
OMhXVXF8kso6UQIDAQABo3cwdTAOBgNVHQ8BAf8EBAMCBaAwHQYDVR0lBBYwFAYI
KwYBBQUHAwEGCCsGAQUFBwMCMAwGA1UdEwEB/wQCMAAwGQYDVR0OBBIEEEYJ/WHM
8p64erPWIg4/liwwGwYDVR0jBBQwEoAQSXyxFFh6tdu62dQFcdieRjANBgkqhkiG
9w0BAQsFAAOBgQA+zH7bHPElWRWJvjxDqRexmYLn+D3Aivs8XgXQJsM94W0EzSUf
DSLfRgaQwcb2gg2xpDFoG+W0vc6O651uF23WGt5JaFFJJxqjII05IexfCNhuPmp4
4UZAXPttuJXpn74IY1tuouaM06B3vXKZR+/ityKmfJvSwxacmFcK+2ziAg==
-----END CERTIFICATE-----
)";

// kBadPSSCertPEM is a self-signed RSA-PSS certificate with bad parameters.
static const char kBadPSSCertPEM[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

static const char kRSAKey[] = R"(
-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----
)";

static const char kP256Key[] = R"(
-----BEGIN PRIVATE KEY-----
MIGHAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBG0wawIBAQQgBw8IcnrUoEqc3VnJ
TYlodwi1b8ldMHcO6NHJzgqLtGqhRANCAATmK2niv2Wfl74vHg2UikzVl2u3qR4N
Rvvdqakendy6WgHn1peoChj5w8SjHlbifINI2xYaHPUdfvGULUvPciLB
-----END PRIVATE KEY-----
)";

// kCRLTestRoot is a test root certificate. It has private key:
//
//     -----BEGIN RSA PRIVATE KEY-----
//     MIIEpAIBAAKCAQEAo16WiLWZuaymsD8n5SKPmxV1y6jjgr3BS/dUBpbrzd1aeFzN
//     lI8l2jfAnzUyp+I21RQ+nh/MhqjGElkTtK9xMn1Y+S9GMRh+5R/Du0iCb1tCZIPY
//     07Tgrb0KMNWe0v2QKVVruuYSgxIWodBfxlKO64Z8AJ5IbnWpuRqO6rctN9qUoMlT
//     IAB6dL4G0tDJ/PGFWOJYwOMEIX54bly2wgyYJVBKiRRt4f7n8H922qmvPNA9idmX
//     9G1VAtgV6x97XXi7ULORIQvn9lVQF6nTYDBJhyuPB+mLThbLP2o9orxGx7aCtnnB
//     ZUIxUvHNOI0FaSaZH7Fi0xsZ/GkG2HZe7ImPJwIDAQABAoIBAQCJF9MTHfHGkk+/
//     DwCXlA0Wg0e6hBuHl10iNobYkMWIl/xXjOknhYiqOqb181py76472SVC5ERprC+r
//     Lf0PXzqKuA117mnkwT2bYLCL9Skf8WEhoFLQNbVlloF6wYjqXcYgKYKh8HgQbZl4
//     aLg2YQl2NADTNABsUWj/4H2WEelsODVviqfFs725lFg9KHDI8zxAZXLzDt/M9uVL
//     GxJiX12tr0AwaeAFZ1oPM/y+LznM3N3+Ht3jHHw3jZ/u8Z1RdAmdpu3bZ6tbwGBr
//     9edsH5rKkm9aBvMrY7eX5VHqaqyRNFyG152ZOJh4XiiFG7EmgTPCpaHo50Y018Re
//     grVtk+FBAoGBANY3lY+V8ZOwMxSHes+kTnoimHO5Ob7nxrOC71i27x+4HHsYUeAr
//     /zOOghiDIn+oNkuiX5CIOWZKx159Bp65CPpCbTb/fh+HYnSgXFgCw7XptycO7LXM
//     5GwR5jSfpfzBFdYxjxoUzDMFBwTEYRTm0HkUHkH+s+ajjw5wqqbcGLcfAoGBAMM8
//     DKW6Tb66xsf708f0jonAjKYTLZ+WOcwsBEWSFHoY8dUjvW5gqx5acHTEsc5ZTeh4
//     BCFLa+Mn9cuJWVJNs09k7Xb2PNl92HQ4GN2vbdkJhExbkT6oLDHg1hVD0w8KLfz1
//     lTAW6pS+6CdOHMEJpvqx89EgU/1GgIQ1fXYczE75AoGAKeJoXdDFkUjsU+FBhAPu
//     TDcjc80Nm2QaF9NMFR5/lsYa236f06MGnQAKM9zADBHJu/Qdl1brUjLg1HrBppsr
//     RDNkw1IlSOjhuUf5hkPUHGd8Jijm440SRIcjabqla8wdBupdvo2+d2NOQgJbsQiI
//     ToQ+fkzcxAXK3Nnuo/1436UCgYBjLH7UNOZHS8OsVM0I1r8NVKVdu4JCfeJQR8/H
//     s2P5ffBir+wLRMnH+nMDreMQiibcPxMCArkERAlE4jlgaJ38Z62E76KLbLTmnJRt
//     EC9Bv+bXjvAiHvWMRMUbOj/ddPNVez7Uld+FvdBaHwDWQlvzHzBWfBCOKSEhh7Z6
//     qDhUqQKBgQDPMDx2i5rfmQp3imV9xUcCkIRsyYQVf8Eo7NV07IdUy/otmksgn4Zt
//     Lbf3v2dvxOpTNTONWjp2c+iUQo8QxJCZr5Sfb21oQ9Ktcrmc/CY7LeBVDibXwxdM
//     vRG8kBzvslFWh7REzC3u06GSVhyKDfW93kN2cKVwGoahRlhj7oHuZQ==
//     -----END RSA PRIVATE KEY-----
static const char kCRLTestRoot[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

static const char kCRLTestLeaf[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

static const char kBasicCRL[] = R"(
-----BEGIN X509 CRL-----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-----END X509 CRL-----
)";

static const char kRevokedCRL[] = R"(
-----BEGIN X509 CRL-----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-----END X509 CRL-----
)";

static const char kBadIssuerCRL[] = R"(
-----BEGIN X509 CRL-----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-----END X509 CRL-----
)";

// kKnownCriticalCRL is kBasicCRL but with a critical issuing distribution point
// extension.
static const char kKnownCriticalCRL[] = R"(
-----BEGIN X509 CRL-----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-----END X509 CRL-----
)";

// kUnknownCriticalCRL is kBasicCRL but with an unknown critical extension.
static const char kUnknownCriticalCRL[] = R"(
-----BEGIN X509 CRL-----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-----END X509 CRL-----
)";

// kUnknownCriticalCRL2 is kBasicCRL but with a critical issuing distribution
// point extension followed by an unknown critical extension
static const char kUnknownCriticalCRL2[] = R"(
-----BEGIN X509 CRL-----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-----END X509 CRL-----
)";

// kBadExtensionCRL is kBasicCRL but with an incorrectly-encoded issuing
// distribution point extension.
static const char kBadExtensionCRL[] = R"(
-----BEGIN X509 CRL-----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-----END X509 CRL-----
)";

// kAlgorithmMismatchCRL is kBasicCRL but with mismatched AlgorithmIdentifiers
// in the outer structure and signed portion. The signature reflects the signed
// portion.
static const char kAlgorithmMismatchCRL[] = R"(
-----BEGIN X509 CRL-----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-----END X509 CRL-----
)";

// kAlgorithmMismatchCRL2 is kBasicCRL but with mismatched AlgorithmIdentifiers
// in the outer structure and signed portion. The signature reflects the outer
// structure.
static const char kAlgorithmMismatchCRL2[] = R"(
-----BEGIN X509 CRL-----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-----END X509 CRL-----
)";

// kEd25519Cert is a self-signed Ed25519 certificate.
static const char kEd25519Cert[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// kEd25519CertNull is an invalid self-signed Ed25519 with an explicit NULL in
// the signature algorithm.
static const char kEd25519CertNull[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// kX25519 is the example X25519 certificate from
// https://tools.ietf.org/html/rfc8410#section-10.2
static const char kX25519Cert[] = R"(
-----BEGIN CERTIFICATE-----
MIIBLDCB36ADAgECAghWAUdKKo3DMDAFBgMrZXAwGTEXMBUGA1UEAwwOSUVURiBUZX
N0IERlbW8wHhcNMTYwODAxMTIxOTI0WhcNNDAxMjMxMjM1OTU5WjAZMRcwFQYDVQQD
DA5JRVRGIFRlc3QgRGVtbzAqMAUGAytlbgMhAIUg8AmJMKdUdIt93LQ+91oNvzoNJj
ga9OukqY6qm05qo0UwQzAPBgNVHRMBAf8EBTADAQEAMA4GA1UdDwEBAAQEAwIDCDAg
BgNVHQ4BAQAEFgQUmx9e7e0EM4Xk97xiPFl1uQvIuzswBQYDK2VwA0EAryMB/t3J5v
/BzKc9dNZIpDmAgs3babFOTQbs+BolzlDUwsPrdGxO3YNGhW7Ibz3OGhhlxXrCe1Cg
w1AH9efZBw==
-----END CERTIFICATE-----
)";

// kMlDsa65Cert is the example ML-DSA-65 certificate from
// https://tools.ietf.org/html/rfc9881#name-example-certificates
static const char kMlDsa65Cert[] = R"(
-----BEGIN CERTIFICATE-----
MIIVjTCCCIqgAwIBAgIUFZ/+byL9XMQsUk32/V4o0N44804wCwYJYIZIAWUDBAMS
MCIxDTALBgNVBAoTBElFVEYxETAPBgNVBAMTCExBTVBTIFdHMB4XDTIwMDIwMzA0
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wDIJVNVyEsrHIp/x1urwOSi9UVEfjYjYR3NsfeJzDVl45UEHExYJeIZ3Eb9VOaC/
xMNQwr5XK68O4uL7Fsz+oIAo2ZrEmuu3WTfdzhEc2rYv/zzqi6IjPR5W+8XFoecm
3mP63SrwFrEZF3+j2XGi2Sdxc/zlW2d0WvC3wh1Zfb65Pmoy80HEmlqL6eglCI0f
KqRRVdbIrhU2fk6wA7j994UQcZSXOfn/8JAj6vRRBNKoSkWQbu1GcaRNwo0nmHu1
XfaenoVh9hqApyaZUDhl/tm37nKo4XoZxAgUT0spr+9wMcOm2FcWELQsn0ISRaiP
GX4WgSsDEVm2W5aH5bPpNMUiWumKebpz0rOZ1zUQ7/rRnlO4RQ8LqPzhAS/ZjSYK
dKqqE/riSaAGscNPW6C4gvJjeCIvs28ig8JD8P/rXxu0FKCnDVXj1ApWtsvIiuHw
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j0swkxVfNmyPpgHGr4WN+jLAhJGyopiH+QM1lJpdbtqmeYgqOpXWv22XCiIfS509
jL84SvgarJXisylOBHiayDcnpdwEVZ+Wr0HYoFNRb+7uvFJ0brarKBngkQhxDYNf
AR+mMGWHKtM01c3/srIxBQfpL8mTrjF9qX9PMJza8PZ+2Z2QIVV2CDhJ+VOyRtf+
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IA==
-----END CERTIFICATE-----
)";

// kMlDsa65CertNull is an invalid self-signed ML-DSA-65 certificate with an
// explicit NULL in the signature algorithm.
static const char kMlDsa65CertNull[] = R"(
-----BEGIN CERTIFICATE-----
MIIVSjCCCEWgAwIBAgIBATANBglghkgBZQMEAxIFADAfMR0wGwYDVQQDDBRtYWxm
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07KHbfltN62DHIWBw5EdGxGWI1wPXaf6J/qmxLRLpmTQgFUM+13YLlyu/N7sNlmM
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C7YfLPKMnjHs/STc2C7x5eeA2lG4gOJBPnwAbY6AWV6jcpkc6p2RW4F9eLhir2p1
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pyOF2aX0lTAFV0oRO2hXru+NKnSBkMk0EZpplwjdhVsfi3jEqdnXk0Svff/lV4W3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-----END CERTIFICATE-----
)";

// kSANTypesLeaf is a leaf certificate (signed by `kSANTypesRoot`) which
// contains SANS for example.com, test@example.com, 127.0.0.1, and
// https://example.com/. (The latter is useless for now since crypto/x509
// doesn't deal with URI SANs directly.)
static const char kSANTypesLeaf[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// -----BEGIN RSA PRIVATE KEY-----
// MIICWwIBAAKBgQDbRn2TLhInBki8Bighq37EtqJd/h5SRYh6NkelCA2SQlvCgcC+
// l3mYQPtPbRT9KxOLwqUuZ9jUCZ7WIji3Sgt0cyvCNPHRk+WW2XR781ifbGE8wLBB
// 1NkrKyQjd1scO711Xc4gVM+hY4cdHiTE8x0aUIuqthRD7ZendWL0FMhS1wIDAQAB
// AoGACwf7z0i1DxOI2zSwFimLghfyCSp8mgT3fbZ3Wj0SebYu6ZUffjceneM/AVrq
// gGYHYLOVHcWJqfkl7X3hPo9SDhzLx0mM545/q21ZWCwjhswH7WiCEqV2/zeDO9WU
// NIO1VU0VoLm0AQ7ZvwnyB+fpgF9kkkDtbBJW7XWrfNVtlnECQQD97YENpEJ3X1kj
// 3rrkrHWDkKAyoWWY1i8Fm7LnganC9Bv6AVwgn5ZlE/479aWHF8vbOFEA3pFPiNZJ
// t9FTCfpJAkEA3RCXjGI0Y6GALFLwEs+nL/XZAfJaIpJEZVLCVosYQOSaMS4SchfC
// GGYVquT7ZgKk9uvz89Fg87OtBMWS9lrkHwJADGkGLKeBhBoJ3kHtem2fVK3F1pOi
// xoR5SdnhNYVVyaxqjZ5xZTrHe+stOrr3uxGDqhQniVZXXb6/Ul0Egv1y2QJAVg/h
// kAujba4wIhFf2VLyOZ+yjil1ocPj0LZ5Zgvcs1bMGJ1hHP3W2HzVrqRaowoggui1
// HpTC891dXGA2qKYV7QJAFDmT2A7OVvh3y4AEgzVwHrDmCMwMHKjCIntS7fjxrJnF
// YvJUG1zoHwUVrxxbR3DbpTODlktLcl/0b97D0IkH3w==
// -----END RSA PRIVATE KEY-----

static const char kSANTypesRoot[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// -----BEGIN RSA PRIVATE KEY-----
// MIICXAIBAAKBgQDpDn8RDOZa5oaDcPZRBy4CeBH1siSSOO4mYgLHlPE+oXdqwI/V
// Imi2XeJM2uCFETXCknJJjYG0iJdrt/yyRFvZTQZw+QzGj+mz36NqhGxDWb6dstB2
// m8PX+plZw7jl81MDvUnWs8yiQ/6twgu5AbhWKZQDJKcNKCEpqa6UW0r5nwIDAQAB
// AoGALEF5daZqc+aEsp8X1yky3nsoheyPL0kqSBWii33IFemZgKcSaRnAoqjPWWLS
// 8dHj0I/4rej2MW8iuezVSpDak9tK5boHORC3w4p/wifkizQkLt1DANxTVbzcKvrt
// aZ7LjVaKkhjRJbLddniowFHkkWVbUccjvzcUd7Y2VuLbAhECQQDq4FE88aHio8zg
// bxSd0PwjEFwLYQTR19u812SoR8PmR6ofIL+pDwOV+fVs+OGcAAOgkhIukOrksQ4A
// 1cKtnyhXAkEA/gRI+u3tZ7UE1twIkBfZ6IvCdRodkPqHAYIxMRLzL+MhyZt4MEGc
// Ngb/F6U9/WOBFnoR/PI7IwE3ejutzKcL+QJBAKh+6eilk7QKPETZi1m3/dmNt+p1
// 3EZJ65pqjwxmB3Rg/vs7vCMk4TarTdSyKu+F1xRPFfoP/mK3Xctdjj6NyhsCQAYF
// 7/0TOzfkUPMPUJyqFB6xgbDpJ55ScnUUsznoqx+NkTWInDb4t02IqO/UmT2y6FKy
// Hk8TJ1fTJY+ebqaVp3ECQApx9gQ+n0zIhx97FMUuiRse73xkcW4+pZ8nF+8DmeQL
// /JKuuFGmzkG+rUbXFmo/Zg2ozVplw71NnQJ4znPsf7A=
// -----END RSA PRIVATE KEY-----

// The following four certificates were generated with this Go program, varying
// `includeNetscapeExtension` and defining rootKeyPEM and rootCertPEM to be
// strings containing the kSANTypesRoot, above.

// clang-format off

// package main

// import (
//     "crypto/ecdsa"
//     "crypto/elliptic"
//     "crypto/rand"
//     "crypto/x509"
//     "crypto/x509/pkix"
//     "encoding/asn1"
//     "encoding/pem"
//     "math/big"
//     "os"
//     "time"
// )

// const includeNetscapeExtension = true

// func main() {
//     block, _ := pem.Decode([]byte(rootKeyPEM))
//     rootPriv, _ := x509.ParsePKCS1PrivateKey(block.Bytes)
//     block, _ = pem.Decode([]byte(rootCertPEM))
//     root, _ := x509.ParseCertificate(block.Bytes)

//     interTemplate := &x509.Certificate{
//         SerialNumber: big.NewInt(2),
//         Subject: pkix.Name{
//             CommonName: "No Basic Constraints (Netscape)",
//         },
//         NotBefore: time.Date(2000, time.January, 1, 0, 0, 0, 0, time.UTC),
//         NotAfter:  time.Date(2099, time.January, 1, 0, 0, 0, 0, time.UTC),
//     }

//     if includeNetscapeExtension {
//         interTemplate.ExtraExtensions = []pkix.Extension{
//             pkix.Extension{
//                 Id:    asn1.ObjectIdentifier([]int{2, 16, 840, 1, 113730, 1, 1}),
//                 Value: []byte{0x03, 0x02, 2, 0x04},
//             },
//         }
//     } else {
//         interTemplate.KeyUsage = x509.KeyUsageCertSign
//     }

//     interKey, _ := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)

//     interDER, err := x509.CreateCertificate(rand.Reader, interTemplate, root, &interKey.PublicKey, rootPriv)
//     if err != nil {
//         panic(err)
//     }

//     pem.Encode(os.Stdout, &pem.Block{Type: "CERTIFICATE", Bytes: interDER})

//     inter, _ := x509.ParseCertificate(interDER)

//     leafTemplate := &x509.Certificate{
//         SerialNumber: big.NewInt(3),
//         Subject: pkix.Name{
//             CommonName: "Leaf from CA with no Basic Constraints",
//         },
//         NotBefore:             time.Date(2000, time.January, 1, 0, 0, 0, 0, time.UTC),
//         NotAfter:              time.Date(2099, time.January, 1, 0, 0, 0, 0, time.UTC),
//         BasicConstraintsValid: true,
//     }
//     leafKey, _ := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)

//     leafDER, err := x509.CreateCertificate(rand.Reader, leafTemplate, inter, &leafKey.PublicKey, interKey)
//     if err != nil {
//         panic(err)
//     }

//     pem.Encode(os.Stdout, &pem.Block{Type: "CERTIFICATE", Bytes: leafDER})
// }

// clang-format on

// kNoBasicConstraintsCertSignIntermediate doesn't have isCA set, but contains
// certSign in the keyUsage.
static const char kNoBasicConstraintsCertSignIntermediate[] = R"(
-----BEGIN CERTIFICATE-----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==
-----END CERTIFICATE-----
)";

static const char kNoBasicConstraintsCertSignLeaf[] = R"(
-----BEGIN CERTIFICATE-----
MIIBUDCB96ADAgECAgEDMAoGCCqGSM49BAMCMB8xHTAbBgNVBAMTFE5vIEJhc2lj
IENvbnN0cmFpbnRzMCAXDTAwMDEwMTAwMDAwMFoYDzIwOTkwMTAxMDAwMDAwWjAx
MS8wLQYDVQQDEyZMZWFmIGZyb20gQ0Egd2l0aCBubyBCYXNpYyBDb25zdHJhaW50
czBZMBMGByqGSM49AgEGCCqGSM49AwEHA0IABEsYPMwzdJKjB+2gpC90ib2ilHoB
w/arQ6ikUX0CNUDDaKaOu/jF39ogzVlg4lDFrjCKShSfCCcrwgONv70IZGijEDAO
MAwGA1UdEwEB/wQCMAAwCgYIKoZIzj0EAwIDSAAwRQIgbV7R99yM+okXSIs6Fp3o
eCOXiDL60IBxaTOcLS44ywcCIQDbn87Gj5cFgHBYAkzdHqDsyGXkxQTHDq9jmX24
Djy3Zw==
-----END CERTIFICATE-----
)";

// kNoBasicConstraintsNetscapeCAIntermediate doesn't have isCA set, but contains
// a Netscape certificate-type extension that asserts a type of "SSL CA".
static const char kNoBasicConstraintsNetscapeCAIntermediate[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

static const char kNoBasicConstraintsNetscapeCALeaf[] = R"(
-----BEGIN CERTIFICATE-----
MIIBXDCCAQKgAwIBAgIBAzAKBggqhkjOPQQDAjAqMSgwJgYDVQQDEx9ObyBCYXNp
YyBDb25zdHJhaW50cyAoTmV0c2NhcGUpMCAXDTAwMDEwMTAwMDAwMFoYDzIwOTkw
MTAxMDAwMDAwWjAxMS8wLQYDVQQDEyZMZWFmIGZyb20gQ0Egd2l0aCBubyBCYXNp
YyBDb25zdHJhaW50czBZMBMGByqGSM49AgEGCCqGSM49AwEHA0IABDlJKolDu3R2
tPqSDycr0QJcWhxdBv76V0EEVflcHRxED6vAioTEcnQszt1OfKtBZvjlo0yp6i6Q
DaYit0ZInmWjEDAOMAwGA1UdEwEB/wQCMAAwCgYIKoZIzj0EAwIDSAAwRQIhAJsh
aZL6BHeEfoUBj1oZ2Ln91qzj3UCVMJ+vrmwAFdYyAiA3wp2JphgchvmoUFuzPXwj
XyPwWPbymSTpzKhB4xB7qQ==
-----END CERTIFICATE-----
)";

static const char kSelfSignedMismatchAlgorithms[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// kCommonNameWithSANs is a leaf certificate signed by kSANTypesRoot, with
// *.host1.test as the common name and a SAN list of *.host2.test and
// foo.host3.test.
static const char kCommonNameWithSANs[] = R"(
-----BEGIN CERTIFICATE-----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=
-----END CERTIFICATE-----
)";

// kCommonNameWithSANs is a leaf certificate signed by kSANTypesRoot, with
// *.host1.test as the common name and no SAN list.
static const char kCommonNameWithoutSANs[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// kCommonNameWithEmailSAN is a leaf certificate signed by kSANTypesRoot, with
// *.host1.test as the common name and the email address test@host2.test in the
// SAN list.
static const char kCommonNameWithEmailSAN[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// kCommonNameWithIPSAN is a leaf certificate signed by kSANTypesRoot, with
// *.host1.test as the common name and the IP address 127.0.0.1 in the
// SAN list.
static const char kCommonNameWithIPSAN[] = R"(
-----BEGIN CERTIFICATE-----
MIIBsTCCARqgAwIBAgIBAjANBgkqhkiG9w0BAQsFADArMRcwFQYDVQQKEw5Cb3Jp
bmdTU0wgVGVzdDEQMA4GA1UEAxMHUm9vdCBDQTAgFw0wMDAxMDEwMDAwMDBaGA8y
MDk5MDEwMTAwMDAwMFowFzEVMBMGA1UEAwwMKi5ob3N0MS50ZXN0MFkwEwYHKoZI
zj0CAQYIKoZIzj0DAQcDQgAEFKrgkxm8PysXbwnHQeTD3p8YY0+sY4ssnZgmj8wX
KTyn893fdBHWlz71GO6t82wMTF5d+ZYwI2XU52pfl4SB2aM+MDwwDAYDVR0TAQH/
BAIwADAbBgNVHSMEFDASgBBAN9cB+0AvuBx+VAQnjFkBMA8GA1UdEQQIMAaHBH8A
AAEwDQYJKoZIhvcNAQELBQADgYEAQWZ8Oj059ZjS109V/ijMYT28xuAN5n6HHxCO
DopTP56Zu9+gme5wTETWEfocspZvgecoUOcedTFoKSQ7JafO09NcVLA+D6ddYpju
mgfuiLy9dDhqvX/NHaLBMxOBWWbOLwWE+ibyX+pOzjWRCw1L7eUXOr6PhZAOQsmU
D0+O6KI=
-----END CERTIFICATE-----
)";

// kConstrainedIntermediate is an intermediate signed by kSANTypesRoot, with
// permitted DNS names of permitted1.test and foo.permitted2.test and an
// excluded DNS name of excluded.permitted1.test. Its private key is:
//
// -----BEGIN PRIVATE KEY-----
// MIGHAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBG0wawIBAQQgTXUM4tJWM7OzATty
// JhNOfIv/d8heWFBeKOfMR+RfaROhRANCAASbbbWYiN6mn+BCpg4XNpibOH0D/DN4
// kZ5C/Ml2YVomC9T83OKk2CzB8fPAabPb4P4Vv+fIabpEfjWS5nzKLY1y
// -----END PRIVATE KEY-----
static const char kConstrainedIntermediate[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// kCommonNamePermittedLeaf is a leaf certificate signed by
// kConstrainedIntermediate. Its common name is permitted by the name
// constraints.
static const char kCommonNamePermittedLeaf[] = R"(
-----BEGIN CERTIFICATE-----
MIIBaDCCAQ2gAwIBAgIBAzAKBggqhkjOPQQDAjAoMSYwJAYDVQQDEx1OYW1lIENv
bnN0cmFpbnRzIEludGVybWVkaWF0ZTAgFw0wMDAxMDEwMDAwMDBaGA8yMDk5MDEw
MTAwMDAwMFowPjEeMBwGA1UEChMVQ29tbW9uIG5hbWUgcGVybWl0dGVkMRwwGgYD
VQQDExNmb28ucGVybWl0dGVkMS50ZXN0MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcD
QgAENX5Ycs8q8MRzPYUz6DqLHhJR3wcmniFRgkiEa7MxE/mRe00y0VGwH7xi7Aoc
emXPrtD4JwN5bssbcxWGAKYYzaMQMA4wDAYDVR0TAQH/BAIwADAKBggqhkjOPQQD
AgNJADBGAiEAtsnWuRQXtw2xbieC78Y8SVEtTjcZUx8uZyQe1GPLfGICIQDR4fNY
yg3PC94ydPNQZVsFxAne32CbonWWsokalTFpUQ==
-----END CERTIFICATE-----
)";
static const char kCommonNamePermitted[] = "foo.permitted1.test";

// kCommonNameNotPermittedLeaf is a leaf certificate signed by
// kConstrainedIntermediate. Its common name is not permitted by the name
// constraints.
static const char kCommonNameNotPermittedLeaf[] = R"(
-----BEGIN CERTIFICATE-----
MIIBazCCARCgAwIBAgIBBDAKBggqhkjOPQQDAjAoMSYwJAYDVQQDEx1OYW1lIENv
bnN0cmFpbnRzIEludGVybWVkaWF0ZTAgFw0wMDAxMDEwMDAwMDBaGA8yMDk5MDEw
MTAwMDAwMFowQTEiMCAGA1UEChMZQ29tbW9uIG5hbWUgbm90IHBlcm1pdHRlZDEb
MBkGA1UEAxMSbm90LXBlcm1pdHRlZC50ZXN0MFkwEwYHKoZIzj0CAQYIKoZIzj0D
AQcDQgAEzfghKuWf0JoXb0Drp09C3yXMSQQ1byt+AUaymvsHOWsxQ9v1Q+vkF/IM
HRqGTk2TyxrB2iClVEn/Uu+YtYox1KMQMA4wDAYDVR0TAQH/BAIwADAKBggqhkjO
PQQDAgNJADBGAiEAxaUslxmoWL1tIvnDz7gDkto/HcmdU0jHVuUQLXcCG8wCIQCN
5xZjitlCQU8UB5qSu9wH4B+0JcVO3Ss4Az76HEJWMw==
-----END CERTIFICATE-----
)";
static const char kCommonNameNotPermitted[] = "not-permitted.test";

// kCommonNameNotPermittedWithSANsLeaf is a leaf certificate signed by
// kConstrainedIntermediate. Its common name is not permitted by the name
// constraints but it has a SAN list.
static const char kCommonNameNotPermittedWithSANsLeaf[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";
static const char kCommonNameNotPermittedWithSANs[] = "not-permitted.test";

// kCommonNameNotDNSLeaf is a leaf certificate signed by
// kConstrainedIntermediate. Its common name is not a DNS name.
static const char kCommonNameNotDNSLeaf[] = R"(
-----BEGIN CERTIFICATE-----
MIIBYTCCAQagAwIBAgIBCDAKBggqhkjOPQQDAjAoMSYwJAYDVQQDEx1OYW1lIENv
bnN0cmFpbnRzIEludGVybWVkaWF0ZTAgFw0wMDAxMDEwMDAwMDBaGA8yMDk5MDEw
MTAwMDAwMFowNzEcMBoGA1UEChMTQ29tbW9uIG5hbWUgbm90IEROUzEXMBUGA1UE
AxMOTm90IGEgRE5TIG5hbWUwWTATBgcqhkjOPQIBBggqhkjOPQMBBwNCAASnueyc
Zxtnw5ke2J2T0/LwAK37auQP/RSFd9mem+BJVbgviawtAlignJmafp7Zw4/GdYEJ
Vm8qlriOJtluvXGcoxAwDjAMBgNVHRMBAf8EAjAAMAoGCCqGSM49BAMCA0kAMEYC
IQChUAmVNI39VHe0zemRE09VDcSEgOxr1nTvjLcg/Q8pVQIhAJYZnJI0YZAi05QH
RHNlAkTK2TnUaVn3fGSylaLiFS1r
-----END CERTIFICATE-----
)";
static const char kCommonNameNotDNS[] = "Not a DNS name";

// The following six certificates are issued by `kSANTypesRoot` and have
// different extended key usage values. They were created with the following
// Go program:
//
// func main() {
//     block, _ := pem.Decode([]byte(rootKeyPEM))
//     rootPriv, _ := x509.ParsePKCS1PrivateKey(block.Bytes)
//     block, _ = pem.Decode([]byte(rootCertPEM))
//     root, _ := x509.ParseCertificate(block.Bytes)
//
//     leafTemplate := &x509.Certificate{
//         SerialNumber: big.NewInt(3),
//         Subject: pkix.Name{
//             CommonName: "EKU msSGC",
//         },
//         NotBefore:             time.Date(2000, time.January, 1, 0, 0, 0, 0,
//         time.UTC), NotAfter:              time.Date(2099, time.January, 1, 0,
//         0, 0, 0, time.UTC), BasicConstraintsValid: true, ExtKeyUsage:
//         []x509.ExtKeyUsage{FILL IN HERE},
//     }
//     leafKey, _ := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
//     leafDER, err := x509.CreateCertificate(rand.Reader, leafTemplate, root,
//     &leafKey.PublicKey, rootPriv) if err != nil {
//         panic(err)
//     }
//     pem.Encode(os.Stdout, &pem.Block{Type: "CERTIFICATE", Bytes: leafDER})
// }

static const char kMicrosoftSGCCert[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

static const char kNetscapeSGCCert[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

static const char kServerEKUCert[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

static const char kServerEKUPlusMicrosoftSGCCert[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

static const char kAnyEKU[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

static const char kNoEKU[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// CertFromPEM parses the given PEM block and returns an `X509`.
static bssl::UniquePtr<X509> CertFromPEM(std::string_view pem) {
  UniquePtr<BIO> bio(BIO_new_mem_buf(pem.data(), pem.size()));
  return UniquePtr<X509>(
      PEM_read_bio_X509(bio.get(), nullptr, nullptr, nullptr));
}

// CRLFromPEM parses the given PEM block and returns an `X509_CRL`.
static bssl::UniquePtr<X509_CRL> CRLFromPEM(std::string_view pem) {
  UniquePtr<BIO> bio(BIO_new_mem_buf(pem.data(), pem.size()));
  return UniquePtr<X509_CRL>(
      PEM_read_bio_X509_CRL(bio.get(), nullptr, nullptr, nullptr));
}

// CSRFromPEM parses the given PEM block and returns an `X509_REQ`.
static bssl::UniquePtr<X509_REQ> CSRFromPEM(std::string_view pem) {
  UniquePtr<BIO> bio(BIO_new_mem_buf(pem.data(), pem.size()));
  return UniquePtr<X509_REQ>(
      PEM_read_bio_X509_REQ(bio.get(), nullptr, nullptr, nullptr));
}

// PrivateKeyFromPEM parses the given PEM block and returns an `EVP_PKEY`.
static bssl::UniquePtr<EVP_PKEY> PrivateKeyFromPEM(std::string_view pem) {
  UniquePtr<BIO> bio(BIO_new_mem_buf(pem.data(), pem.size()));
  return UniquePtr<EVP_PKEY>(
      PEM_read_bio_PrivateKey(bio.get(), nullptr, nullptr, nullptr));
}

// CertsToStack converts a vector of `X509*` to an OpenSSL STACK_OF(X509),
// bumping the reference counts for each certificate in question.
static bssl::UniquePtr<STACK_OF(X509)> CertsToStack(
    const std::vector<X509 *> &certs) {
  UniquePtr<STACK_OF(X509)> stack(sk_X509_new_null());
  if (!stack) {
    return nullptr;
  }
  for (auto cert : certs) {
    if (!PushToStack(stack.get(), UpRef(cert))) {
      return nullptr;
    }
  }

  return stack;
}

static bssl::Span<const uint8_t> ASN1StringAsBytes(const ASN1_STRING *str) {
  return Span(ASN1_STRING_get0_data(str), ASN1_STRING_length(str));
}

static std::string_view ASN1StringAsView(const ASN1_STRING *str) {
  return BytesAsStringView(ASN1StringAsBytes(str));
}

// CRLsToStack converts a vector of `X509_CRL*` to an OpenSSL
// STACK_OF(X509_CRL), bumping the reference counts for each CRL in question.
static bssl::UniquePtr<STACK_OF(X509_CRL)> CRLsToStack(
    const std::vector<X509_CRL *> &crls) {
  UniquePtr<STACK_OF(X509_CRL)> stack(sk_X509_CRL_new_null());
  if (!stack) {
    return nullptr;
  }
  for (auto crl : crls) {
    if (!PushToStack(stack.get(), UpRef(crl))) {
      return nullptr;
    }
  }

  return stack;
}

static const int64_t kReferenceTime = 1474934400 /* Sep 27th, 2016 */;

static int Verify(
    X509 *leaf, const std::vector<X509 *> &roots,
    const std::vector<X509 *> &intermediates,
    const std::vector<X509_CRL *> &crls, unsigned long flags = 0,
    std::function<void(X509_STORE_CTX *)> configure_callback = nullptr) {
  UniquePtr<STACK_OF(X509)> roots_stack(CertsToStack(roots));
  UniquePtr<STACK_OF(X509)> intermediates_stack(CertsToStack(intermediates));
  UniquePtr<STACK_OF(X509_CRL)> crls_stack(CRLsToStack(crls));

  if (!roots_stack ||          //
      !intermediates_stack ||  //
      !crls_stack) {
    return X509_V_ERR_UNSPECIFIED;
  }

  UniquePtr<X509_STORE_CTX> ctx(X509_STORE_CTX_new());
  UniquePtr<X509_STORE> store(X509_STORE_new());
  if (!ctx ||  //
      !store) {
    return X509_V_ERR_UNSPECIFIED;
  }

  if (!X509_STORE_CTX_init(ctx.get(), store.get(), leaf,
                           intermediates_stack.get())) {
    return X509_V_ERR_UNSPECIFIED;
  }

  X509_STORE_CTX_set0_trusted_stack(ctx.get(), roots_stack.get());
  X509_STORE_CTX_set0_crls(ctx.get(), crls_stack.get());

  X509_VERIFY_PARAM *param = X509_STORE_CTX_get0_param(ctx.get());
  X509_VERIFY_PARAM_set_time_posix(param, kReferenceTime);
  if (configure_callback) {
    configure_callback(ctx.get());
  }
  if (flags) {
    X509_VERIFY_PARAM_set_flags(param, flags);
  }

  ERR_clear_error();
  if (X509_verify_cert(ctx.get()) != 1) {
    return X509_STORE_CTX_get_error(ctx.get());
  }

  return X509_V_OK;
}

TEST(X509Test, TestVerify) {
  //  cross_signing_root
  //         |
  //   root_cross_signed    root
  //              \         /
  //             intermediate
  //                |     |
  //              leaf  leaf_no_key_usage
  //                      |
  //                    forgery
  UniquePtr<X509> cross_signing_root(CertFromPEM(kCrossSigningRootPEM));
  UniquePtr<X509> root(CertFromPEM(kRootCAPEM));
  UniquePtr<X509> root_cross_signed(CertFromPEM(kRootCrossSignedPEM));
  UniquePtr<X509> intermediate(CertFromPEM(kIntermediatePEM));
  UniquePtr<X509> intermediate_self_signed(
      CertFromPEM(kIntermediateSelfSignedPEM));
  UniquePtr<X509> leaf(CertFromPEM(kLeafPEM));
  UniquePtr<X509> leaf_no_key_usage(CertFromPEM(kLeafNoKeyUsagePEM));
  UniquePtr<X509> forgery(CertFromPEM(kForgeryPEM));

  ASSERT_TRUE(cross_signing_root);
  ASSERT_TRUE(root);
  ASSERT_TRUE(root_cross_signed);
  ASSERT_TRUE(intermediate);
  ASSERT_TRUE(intermediate_self_signed);
  ASSERT_TRUE(leaf);
  ASSERT_TRUE(forgery);
  ASSERT_TRUE(leaf_no_key_usage);

  // Most of these tests work with or without `X509_V_FLAG_TRUSTED_FIRST`,
  // though in different ways.
  for (bool trusted_first : {true, false}) {
    SCOPED_TRACE(trusted_first);
    bool override_depth = false;
    int depth = -1;
    auto configure_callback = [&](X509_STORE_CTX *ctx) {
      X509_VERIFY_PARAM *param = X509_STORE_CTX_get0_param(ctx);
      // Note we need the callback to clear the flag. Setting `flags` to zero
      // only skips setting new flags.
      if (!trusted_first) {
        X509_VERIFY_PARAM_clear_flags(param, X509_V_FLAG_TRUSTED_FIRST);
      }
      if (override_depth) {
        X509_VERIFY_PARAM_set_depth(param, depth);
      }
    };

    // No trust anchors configured.
    EXPECT_EQ(X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY,
              Verify(leaf.get(), /*roots=*/{}, /*intermediates=*/{},
                     /*crls=*/{}, /*flags=*/0, configure_callback));
    EXPECT_EQ(
        X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY,
        Verify(leaf.get(), /*roots=*/{}, {intermediate.get()}, /*crls=*/{},
               /*flags=*/0, configure_callback));

    // Each chain works individually.
    EXPECT_EQ(X509_V_OK, Verify(leaf.get(), {root.get()}, {intermediate.get()},
                                /*crls=*/{}, /*flags=*/0, configure_callback));
    EXPECT_EQ(X509_V_OK, Verify(leaf.get(), {cross_signing_root.get()},
                                {intermediate.get(), root_cross_signed.get()},
                                /*crls=*/{}, /*flags=*/0, configure_callback));

    // When both roots are available, we pick one or the other.
    EXPECT_EQ(X509_V_OK,
              Verify(leaf.get(), {cross_signing_root.get(), root.get()},
                     {intermediate.get(), root_cross_signed.get()}, /*crls=*/{},
                     /*flags=*/0, configure_callback));

    // This is the “altchains” test – we remove the cross-signing CA but include
    // the cross-sign in the intermediates. With `trusted_first`, we
    // preferentially stop path-building at `intermediate`. Without
    // `trusted_first`, the "altchains" logic repairs it.
    EXPECT_EQ(X509_V_OK, Verify(leaf.get(), {root.get()},
                                {intermediate.get(), root_cross_signed.get()},
                                /*crls=*/{}, /*flags=*/0, configure_callback));

    // If `X509_V_FLAG_NO_ALT_CHAINS` is set and `trusted_first` is disabled, we
    // get stuck on `root_cross_signed`. If either feature is enabled, we can
    // build the path.
    //
    // This test exists to confirm our current behavior, but these modes are
    // just workarounds for not having an actual path-building verifier. If we
    // fix it, this test can be removed.
    EXPECT_EQ(trusted_first ? X509_V_OK
                            : X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY,
              Verify(leaf.get(), {root.get()},
                     {intermediate.get(), root_cross_signed.get()}, /*crls=*/{},
                     /*flags=*/X509_V_FLAG_NO_ALT_CHAINS, configure_callback));

    // `forgery` is signed by `leaf_no_key_usage`, but is rejected because the
    // leaf is not a CA.
    EXPECT_EQ(X509_V_ERR_INVALID_CA,
              Verify(forgery.get(), {intermediate_self_signed.get()},
                     {leaf_no_key_usage.get()}, /*crls=*/{}, /*flags=*/0,
                     configure_callback));

    // Test that one cannot skip Basic Constraints checking with a contorted set
    // of roots and intermediates. This is a regression test for CVE-2015-1793.
    EXPECT_EQ(X509_V_ERR_INVALID_CA,
              Verify(forgery.get(),
                     {intermediate_self_signed.get(), root_cross_signed.get()},
                     {leaf_no_key_usage.get(), intermediate.get()}, /*crls=*/{},
                     /*flags=*/0, configure_callback));

    // Test depth limits. `configure_callback` looks at `override_depth` and
    // `depth`. Negative numbers have historically worked, so test those too.
    for (int d : {-4, -3, -2, -1, 0, 1, 2, 3, 4, INT_MAX - 3, INT_MAX - 2,
                  INT_MAX - 1, INT_MAX}) {
      SCOPED_TRACE(d);
      override_depth = true;
      depth = d;
      // A chain with a leaf, two intermediates, and a root is depth two.
      EXPECT_EQ(
          depth >= 2 ? X509_V_OK : X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY,
          Verify(leaf.get(), {cross_signing_root.get()},
                 {intermediate.get(), root_cross_signed.get()},
                 /*crls=*/{}, /*flags=*/0, configure_callback));

      // A chain with a leaf, a root, and no intermediates is depth zero.
      EXPECT_EQ(
          depth >= 0 ? X509_V_OK : X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY,
          Verify(root_cross_signed.get(), {cross_signing_root.get()}, {},
                 /*crls=*/{}, /*flags=*/0, configure_callback));

      // An explicitly trusted self-signed certificate is unaffected by depth
      // checks.
      EXPECT_EQ(X509_V_OK,
                Verify(cross_signing_root.get(), {cross_signing_root.get()}, {},
                       /*crls=*/{}, /*flags=*/0, configure_callback));
    }
  }
}

#if defined(OPENSSL_THREADS)
// Verifying the same `X509` objects on two threads should be safe.
TEST(X509Test, VerifyThreads) {
  UniquePtr<X509> root(CertFromPEM(kRootCAPEM));
  UniquePtr<X509> intermediate(CertFromPEM(kIntermediatePEM));
  UniquePtr<X509> leaf(CertFromPEM(kLeafPEM));
  ASSERT_TRUE(root);
  ASSERT_TRUE(intermediate);
  ASSERT_TRUE(leaf);

  const size_t kNumThreads = 10;
  std::vector<std::thread> threads;
  for (size_t i = 0; i < kNumThreads; i++) {
    threads.emplace_back([&] {
      EXPECT_EQ(X509_V_OK,
                Verify(leaf.get(), {root.get()}, {intermediate.get()},
                       /*crls=*/{}));
    });
  }
  for (auto &thread : threads) {
    thread.join();
  }
}

// Using the same CRL on two threads should be safe.
TEST(X509Test, CRLThreads) {
  UniquePtr<X509> root(CertFromPEM(kCRLTestRoot));
  UniquePtr<X509> leaf(CertFromPEM(kCRLTestLeaf));
  UniquePtr<X509_CRL> basic_crl(CRLFromPEM(kBasicCRL));
  UniquePtr<X509_CRL> revoked_crl(CRLFromPEM(kRevokedCRL));
  ASSERT_TRUE(root);
  ASSERT_TRUE(leaf);
  ASSERT_TRUE(basic_crl);
  ASSERT_TRUE(revoked_crl);

  const size_t kNumThreads = 10;
  std::vector<std::thread> threads;
  for (size_t i = 0; i < kNumThreads; i++) {
    threads.emplace_back([&] {
      EXPECT_EQ(X509_V_OK, Verify(leaf.get(), {root.get()}, {root.get()},
                                  {basic_crl.get()}, X509_V_FLAG_CRL_CHECK));
    });
    threads.emplace_back([&] {
      EXPECT_EQ(X509_V_ERR_CERT_REVOKED,
                Verify(leaf.get(), {root.get()}, {root.get()},
                       {revoked_crl.get()}, X509_V_FLAG_CRL_CHECK));
    });
  }

  for (auto &thread : threads) {
    thread.join();
  }

  // TODO(crbug.com/boringssl/600): Add a thread that iterates
  // `X509_CRL_get_REVOKED` and a thread that calls `X509_CRL_print`. Those
  // currently do not work correctly.
}

TEST(X509Test, StoreThreads) {
  UniquePtr<X509> root(CertFromPEM(kRootCAPEM));
  UniquePtr<X509> intermediate(CertFromPEM(kIntermediatePEM));
  UniquePtr<X509> leaf(CertFromPEM(kLeafPEM));
  ASSERT_TRUE(root);
  ASSERT_TRUE(intermediate);
  ASSERT_TRUE(leaf);

  UniquePtr<STACK_OF(X509)> intermediates = CertsToStack({intermediate.get()});
  ASSERT_TRUE(intermediates);

  // Some unrelated certificates.
  UniquePtr<X509> other1(CertFromPEM(kCRLTestRoot));
  UniquePtr<X509> other2(CertFromPEM(kCRLTestLeaf));
  ASSERT_TRUE(other1);
  ASSERT_TRUE(other2);

  UniquePtr<X509_STORE> store(X509_STORE_new());
  ASSERT_TRUE(store);
  ASSERT_TRUE(X509_STORE_add_cert(store.get(), root.get()));

  const size_t kNumThreads = 10;
  std::vector<std::thread> threads;
  for (size_t i = 0; i < kNumThreads; i++) {
    threads.emplace_back([&] {
      UniquePtr<X509_STORE_CTX> ctx(X509_STORE_CTX_new());
      ASSERT_TRUE(ctx);
      ASSERT_TRUE(X509_STORE_CTX_init(ctx.get(), store.get(), leaf.get(),
                                      intermediates.get()));
      X509_STORE_CTX_set_time_posix(ctx.get(), /*flags=*/0, kReferenceTime);
      ASSERT_TRUE(X509_verify_cert(ctx.get()));
      ASSERT_EQ(X509_STORE_CTX_get_error(ctx.get()), X509_V_OK);
    });
    threads.emplace_back(
        [&] { ASSERT_TRUE(X509_STORE_add_cert(store.get(), other1.get())); });
    threads.emplace_back(
        [&] { ASSERT_TRUE(X509_STORE_add_cert(store.get(), other2.get())); });
    threads.emplace_back([&] {
      UniquePtr<STACK_OF(X509_OBJECT)> objs(
          X509_STORE_get1_objects(store.get()));
      ASSERT_TRUE(objs);
    });
  }
  for (auto &thread : threads) {
    thread.join();
  }
}

// Test that serializing a modified `X509_NAME` object on multiple threads is
// thread-safe. This historically wasn't because OpenSSL's `X509_NAME` object
// maintains a number of caches.
TEST(X509Test, SerializeModifiedNameThreads) {
  UniquePtr<X509_NAME> name(X509_NAME_new());
  ASSERT_TRUE(name);
  ASSERT_TRUE(
      X509_NAME_add_entry_by_txt(name.get(), "CN", MBSTRING_UTF8,
                                 reinterpret_cast<const uint8_t *>("Test"),
                                 /*len=*/-1, /*loc=*/-1, /*set=*/0));

  const size_t kNumThreads = 10;
  std::vector<std::thread> threads;
  for (size_t i = 0; i < kNumThreads; i++) {
    threads.emplace_back([&] {
      uint8_t *der = nullptr;
      int der_len = i2d_X509_NAME(name.get(), &der);
      ASSERT_GT(der_len, 0);
      OPENSSL_free(der);
    });
  }
  for (auto &thread : threads) {
    thread.join();
  }
}

// Test that serializing a modified `X509` object on multiple threads is
// thread-safe. This historically wasn't true because OpenSSL's `X509_NAME`
// object maintains a number of caches, and because `X509_get_issuer_name` and
// `X509_get_subject_name` aren't const-correct and allow direct, mutable access
// to the `X509`'s subject and issuer.
TEST(X509Test, SerializeModifiedCertThreads) {
  UniquePtr<X509> cert = CertFromPEM(kLeafPEM);
  ASSERT_TRUE(cert);

  // Re-encode the TBSCertificate, dropping the cached encoding. As currently
  // implemented, once the cached encoding is dropped, it is never recreated.
  // Instead, it's assumed that the DER encoder will reproduce the expected
  // encoding. https://crbug.com/443261873 discusses changing this model.
  uint8_t *tbs = nullptr;
  int tbs_len = i2d_re_X509_tbs(cert.get(), &tbs);
  ASSERT_GT(tbs_len, 0);
  OPENSSL_free(tbs);

  // Modify the subject name directly, now that there is no cached encoding.
  ASSERT_TRUE(X509_NAME_add_entry_by_txt(
      X509_get_subject_name(cert.get()), "CN", MBSTRING_UTF8,
      reinterpret_cast<const uint8_t *>("Test"),
      /*len=*/-1, /*loc=*/-1, /*set=*/0));

  // Now serialize the certificate in parallel. This should be safe to use
  // across threads. Historically, this would expose the underlying `X509_NAME`
  // encoder not being thread-safe.
  const size_t kNumThreads = 10;
  std::vector<std::thread> threads;
  for (size_t i = 0; i < kNumThreads; i++) {
    threads.emplace_back([&] {
      uint8_t *der = nullptr;
      int der_len = i2d_X509(cert.get(), &der);
      ASSERT_GT(der_len, 0);
      OPENSSL_free(der);
    });
  }
  for (auto &thread : threads) {
    thread.join();
  }
}
#endif  // OPENSSL_THREADS

static const char kHostname[] = "example.com";
static const char kWrongHostname[] = "example2.com";
static const char kEmail[] = "test@example.com";
static const char kWrongEmail[] = "test2@example.com";
static const uint8_t kIP[4] = {127, 0, 0, 1};
static const uint8_t kWrongIP[4] = {127, 0, 0, 2};
static const char kIPString[] = "127.0.0.1";
static const char kWrongIPString[] = "127.0.0.2";

TEST(X509Test, ZeroLengthsWithX509PARAM) {
  UniquePtr<X509> leaf(CertFromPEM(kSANTypesLeaf));
  UniquePtr<X509> root(CertFromPEM(kSANTypesRoot));
  ASSERT_TRUE(leaf);
  ASSERT_TRUE(root);

  std::vector<X509_CRL *> empty_crls;

  struct X509Test {
    const char *correct_value;
    size_t correct_value_len;
    const char *incorrect_value;
    size_t incorrect_value_len;
    int (*func)(X509_VERIFY_PARAM *, const char *, size_t);
    int mismatch_error;
  };
  const std::vector<X509Test> kTests = {
      {kHostname, strlen(kHostname), kWrongHostname, strlen(kWrongHostname),
       X509_VERIFY_PARAM_set1_host, X509_V_ERR_HOSTNAME_MISMATCH},
      {kEmail, strlen(kEmail), kWrongEmail, strlen(kWrongEmail),
       X509_VERIFY_PARAM_set1_email, X509_V_ERR_EMAIL_MISMATCH},
  };

  for (size_t i = 0; i < kTests.size(); i++) {
    SCOPED_TRACE(i);
    const X509Test &test = kTests[i];

    // The correct value should work.
    ASSERT_EQ(X509_V_OK,
              Verify(leaf.get(), {root.get()}, {}, empty_crls, 0,
                     [&test](X509_STORE_CTX *ctx) {
                       X509_VERIFY_PARAM *param =
                           X509_STORE_CTX_get0_param(ctx);
                       ASSERT_TRUE(test.func(param, test.correct_value,
                                             test.correct_value_len));
                     }));

    // The wrong value should trigger a verification error.
    ASSERT_EQ(test.mismatch_error,
              Verify(leaf.get(), {root.get()}, {}, empty_crls, 0,
                     [&test](X509_STORE_CTX *ctx) {
                       X509_VERIFY_PARAM *param =
                           X509_STORE_CTX_get0_param(ctx);
                       ASSERT_TRUE(test.func(param, test.incorrect_value,
                                             test.incorrect_value_len));
                     }));

    // Passing zero as the length, unlike OpenSSL, should trigger an error and
    // should cause verification to fail.
    ASSERT_EQ(X509_V_ERR_INVALID_CALL,
              Verify(leaf.get(), {root.get()}, {}, empty_crls, 0,
                     [&test](X509_STORE_CTX *ctx) {
                       X509_VERIFY_PARAM *param =
                           X509_STORE_CTX_get0_param(ctx);
                       ASSERT_FALSE(test.func(param, test.correct_value, 0));
                     }));

    // Passing an empty value should be an error when setting and should cause
    // verification to fail.
    ASSERT_EQ(X509_V_ERR_INVALID_CALL,
              Verify(leaf.get(), {root.get()}, {}, empty_crls, 0,
                     [&test](X509_STORE_CTX *ctx) {
                       X509_VERIFY_PARAM *param =
                           X509_STORE_CTX_get0_param(ctx);
                       ASSERT_FALSE(test.func(param, nullptr, 0));
                     }));

    // Passing a value with embedded NULs should also be an error and should
    // also cause verification to fail.
    ASSERT_EQ(X509_V_ERR_INVALID_CALL,
              Verify(leaf.get(), {root.get()}, {}, empty_crls, 0,
                     [&test](X509_STORE_CTX *ctx) {
                       X509_VERIFY_PARAM *param =
                           X509_STORE_CTX_get0_param(ctx);
                       ASSERT_FALSE(test.func(param, "a", 2));
                     }));
  }

  // IP addresses work slightly differently:

  // The correct value should still work.
  ASSERT_EQ(
      X509_V_OK,
      Verify(leaf.get(), {root.get()}, {}, empty_crls, 0,
             [](X509_STORE_CTX *ctx) {
               X509_VERIFY_PARAM *param = X509_STORE_CTX_get0_param(ctx);
               ASSERT_TRUE(X509_VERIFY_PARAM_set1_ip(param, kIP, sizeof(kIP)));
             }));

  // Incorrect values should still fail.
  ASSERT_EQ(X509_V_ERR_IP_ADDRESS_MISMATCH,
            Verify(leaf.get(), {root.get()}, {}, empty_crls, 0,
                   [](X509_STORE_CTX *ctx) {
                     X509_VERIFY_PARAM *param = X509_STORE_CTX_get0_param(ctx);
                     ASSERT_TRUE(X509_VERIFY_PARAM_set1_ip(param, kWrongIP,
                                                           sizeof(kWrongIP)));
                   }));

  // Zero length values should trigger an error when setting and cause
  // verification to always fail.
  ASSERT_EQ(X509_V_ERR_INVALID_CALL,
            Verify(leaf.get(), {root.get()}, {}, empty_crls, 0,
                   [](X509_STORE_CTX *ctx) {
                     X509_VERIFY_PARAM *param = X509_STORE_CTX_get0_param(ctx);
                     ASSERT_FALSE(X509_VERIFY_PARAM_set1_ip(param, kIP, 0));
                   }));

  // ... and so should NULL values.
  ASSERT_EQ(X509_V_ERR_INVALID_CALL,
            Verify(leaf.get(), {root.get()}, {}, empty_crls, 0,
                   [](X509_STORE_CTX *ctx) {
                     X509_VERIFY_PARAM *param = X509_STORE_CTX_get0_param(ctx);
                     ASSERT_FALSE(X509_VERIFY_PARAM_set1_ip(param, nullptr, 0));
                   }));

  // Zero bytes in an IP address are, of course, fine. This is tested above
  // because `kIP` contains zeros.
}

TEST(X509Test, ZeroLengthsWithCheckFunctions) {
  UniquePtr<X509> leaf(CertFromPEM(kSANTypesLeaf));
  ASSERT_TRUE(leaf);

  EXPECT_EQ(
      1, X509_check_host(leaf.get(), kHostname, strlen(kHostname), 0, nullptr));
  EXPECT_NE(1, X509_check_host(leaf.get(), kWrongHostname,
                               strlen(kWrongHostname), 0, nullptr));

  EXPECT_EQ(1, X509_check_email(leaf.get(), kEmail, strlen(kEmail), 0));
  EXPECT_NE(1,
            X509_check_email(leaf.get(), kWrongEmail, strlen(kWrongEmail), 0));

  EXPECT_EQ(1, X509_check_ip(leaf.get(), kIP, sizeof(kIP), 0));
  EXPECT_NE(1, X509_check_ip(leaf.get(), kWrongIP, sizeof(kWrongIP), 0));

  EXPECT_EQ(1, X509_check_ip_asc(leaf.get(), kIPString, 0));
  EXPECT_NE(1, X509_check_ip_asc(leaf.get(), kWrongIPString, 0));

  // OpenSSL supports passing zero as the length for host and email. We do not
  // and it should always fail.
  EXPECT_NE(1, X509_check_host(leaf.get(), kHostname, 0, 0, nullptr));
  EXPECT_NE(1, X509_check_host(leaf.get(), kWrongHostname, 0, 0, nullptr));

  EXPECT_NE(1, X509_check_email(leaf.get(), kEmail, 0, 0));
  EXPECT_NE(1, X509_check_email(leaf.get(), kWrongEmail, 0, 0));

  EXPECT_NE(1, X509_check_ip(leaf.get(), kIP, 0, 0));
  EXPECT_NE(1, X509_check_ip(leaf.get(), kWrongIP, 0, 0));

  // Unlike all the other functions, `X509_check_ip_asc` doesn't take a length,
  // so it cannot be zero.
}

TEST(X509Test, TestCRL) {
  UniquePtr<X509> root(CertFromPEM(kCRLTestRoot));
  UniquePtr<X509> leaf(CertFromPEM(kCRLTestLeaf));
  UniquePtr<X509_CRL> basic_crl(CRLFromPEM(kBasicCRL));
  UniquePtr<X509_CRL> revoked_crl(CRLFromPEM(kRevokedCRL));
  UniquePtr<X509_CRL> bad_issuer_crl(CRLFromPEM(kBadIssuerCRL));
  UniquePtr<X509_CRL> known_critical_crl(CRLFromPEM(kKnownCriticalCRL));
  UniquePtr<X509_CRL> unknown_critical_crl(CRLFromPEM(kUnknownCriticalCRL));
  UniquePtr<X509_CRL> unknown_critical_crl2(CRLFromPEM(kUnknownCriticalCRL2));
  UniquePtr<X509_CRL> algorithm_mismatch_crl(CRLFromPEM(kAlgorithmMismatchCRL));
  UniquePtr<X509_CRL> algorithm_mismatch_crl2(
      CRLFromPEM(kAlgorithmMismatchCRL2));

  ASSERT_TRUE(root);
  ASSERT_TRUE(leaf);
  ASSERT_TRUE(basic_crl);
  ASSERT_TRUE(revoked_crl);
  ASSERT_TRUE(bad_issuer_crl);
  ASSERT_TRUE(known_critical_crl);
  ASSERT_TRUE(unknown_critical_crl);
  ASSERT_TRUE(unknown_critical_crl2);
  ASSERT_TRUE(algorithm_mismatch_crl);
  ASSERT_TRUE(algorithm_mismatch_crl2);

  EXPECT_EQ(X509_V_OK, Verify(leaf.get(), {root.get()}, {root.get()},
                              {basic_crl.get()}, X509_V_FLAG_CRL_CHECK));
  EXPECT_EQ(
      X509_V_ERR_CERT_REVOKED,
      Verify(leaf.get(), {root.get()}, {root.get()},
             {basic_crl.get(), revoked_crl.get()}, X509_V_FLAG_CRL_CHECK));

  std::vector<X509_CRL *> empty_crls;
  EXPECT_EQ(X509_V_ERR_UNABLE_TO_GET_CRL,
            Verify(leaf.get(), {root.get()}, {root.get()}, empty_crls,
                   X509_V_FLAG_CRL_CHECK));
  EXPECT_EQ(X509_V_ERR_UNABLE_TO_GET_CRL,
            Verify(leaf.get(), {root.get()}, {root.get()},
                   {bad_issuer_crl.get()}, X509_V_FLAG_CRL_CHECK));
  EXPECT_EQ(X509_V_OK,
            Verify(leaf.get(), {root.get()}, {root.get()},
                   {known_critical_crl.get()}, X509_V_FLAG_CRL_CHECK));
  EXPECT_EQ(X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION,
            Verify(leaf.get(), {root.get()}, {root.get()},
                   {unknown_critical_crl.get()}, X509_V_FLAG_CRL_CHECK));
  EXPECT_EQ(X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION,
            Verify(leaf.get(), {root.get()}, {root.get()},
                   {unknown_critical_crl2.get()}, X509_V_FLAG_CRL_CHECK));
  EXPECT_EQ(X509_V_ERR_CRL_SIGNATURE_FAILURE,
            Verify(leaf.get(), {root.get()}, {root.get()},
                   {algorithm_mismatch_crl.get()}, X509_V_FLAG_CRL_CHECK));
  EXPECT_EQ(X509_V_ERR_CRL_SIGNATURE_FAILURE,
            Verify(leaf.get(), {root.get()}, {root.get()},
                   {algorithm_mismatch_crl2.get()}, X509_V_FLAG_CRL_CHECK));

  // The CRL is valid for a month.
  EXPECT_EQ(X509_V_ERR_CRL_HAS_EXPIRED,
            Verify(leaf.get(), {root.get()}, {root.get()}, {basic_crl.get()},
                   X509_V_FLAG_CRL_CHECK, [](X509_STORE_CTX *ctx) {
                     X509_STORE_CTX_set_time_posix(
                         ctx, /*flags=*/0, kReferenceTime + 2 * 30 * 24 * 3600);
                   }));

  // X509_V_FLAG_NO_CHECK_TIME suppresses the validity check.
  EXPECT_EQ(X509_V_OK,
            Verify(leaf.get(), {root.get()}, {root.get()}, {basic_crl.get()},
                   X509_V_FLAG_CRL_CHECK | X509_V_FLAG_NO_CHECK_TIME,
                   [](X509_STORE_CTX *ctx) {
                     X509_STORE_CTX_set_time_posix(
                         ctx, /*flags=*/0, kReferenceTime + 2 * 30 * 24 * 3600);
                   }));

  // We no longer support indirect or delta CRLs.
  EXPECT_EQ(X509_V_ERR_INVALID_CALL,
            Verify(leaf.get(), {root.get()}, {root.get()}, {basic_crl.get()},
                   X509_V_FLAG_CRL_CHECK | X509_V_FLAG_EXTENDED_CRL_SUPPORT));
  EXPECT_EQ(X509_V_ERR_INVALID_CALL,
            Verify(leaf.get(), {root.get()}, {root.get()}, {basic_crl.get()},
                   X509_V_FLAG_CRL_CHECK | X509_V_FLAG_USE_DELTAS));

  // Parsing kBadExtensionCRL should fail.
  EXPECT_FALSE(CRLFromPEM(kBadExtensionCRL));
}

TEST(X509Test, ManyNamesAndConstraints) {
  UniquePtr<X509> many_constraints(
      CertFromPEM(GetTestData("crypto/x509/test/many_constraints.pem")));
  ASSERT_TRUE(many_constraints);
  UniquePtr<X509> many_names1(
      CertFromPEM(GetTestData("crypto/x509/test/many_names1.pem")));
  ASSERT_TRUE(many_names1);
  UniquePtr<X509> many_names2(
      CertFromPEM(GetTestData("crypto/x509/test/many_names2.pem")));
  ASSERT_TRUE(many_names2);
  UniquePtr<X509> many_names3(
      CertFromPEM(GetTestData("crypto/x509/test/many_names3.pem")));
  ASSERT_TRUE(many_names3);
  UniquePtr<X509> some_names1(
      CertFromPEM(GetTestData("crypto/x509/test/some_names1.pem")));
  ASSERT_TRUE(some_names1);
  UniquePtr<X509> some_names2(
      CertFromPEM(GetTestData("crypto/x509/test/some_names2.pem")));
  ASSERT_TRUE(some_names2);
  UniquePtr<X509> some_names3(
      CertFromPEM(GetTestData("crypto/x509/test/some_names3.pem")));
  ASSERT_TRUE(some_names3);

  EXPECT_EQ(X509_V_ERR_UNSPECIFIED,
            Verify(many_names1.get(), {many_constraints.get()},
                   {many_constraints.get()}, {}));
  EXPECT_EQ(X509_V_ERR_UNSPECIFIED,
            Verify(many_names2.get(), {many_constraints.get()},
                   {many_constraints.get()}, {}));
  EXPECT_EQ(X509_V_ERR_UNSPECIFIED,
            Verify(many_names3.get(), {many_constraints.get()},
                   {many_constraints.get()}, {}));

  EXPECT_EQ(X509_V_OK, Verify(some_names1.get(), {many_constraints.get()},
                              {many_constraints.get()}, {}));
  EXPECT_EQ(X509_V_OK, Verify(some_names2.get(), {many_constraints.get()},
                              {many_constraints.get()}, {}));
  EXPECT_EQ(X509_V_OK, Verify(some_names3.get(), {many_constraints.get()},
                              {many_constraints.get()}, {}));
}

static bssl::UniquePtr<GENERAL_NAME> MakeGeneralName(int type,
                                                     std::string_view value) {
  if (type != GEN_EMAIL && type != GEN_DNS && type != GEN_URI) {
    // This function only supports the IA5String types.
    return nullptr;
  }
  UniquePtr<ASN1_IA5STRING> str(ASN1_IA5STRING_new());
  UniquePtr<GENERAL_NAME> name(GENERAL_NAME_new());
  if (!str || !name ||
      !ASN1_STRING_set(str.get(), value.data(), value.size())) {
    return nullptr;
  }

  name->type = type;
  name->d.ia5 = str.release();
  return name;
}

static bssl::UniquePtr<X509_NAME> MakeTestName(std::string_view common_name) {
  auto bytes = StringAsBytes(common_name);
  UniquePtr<X509_NAME> name(X509_NAME_new());
  if (name == nullptr ||
      !X509_NAME_add_entry_by_txt(name.get(), "CN", MBSTRING_UTF8, bytes.data(),
                                  bytes.size(), -1, 0)) {
    return nullptr;
  }
  return name;
}

static bssl::UniquePtr<X509> MakeTestCert(
    std::string_view issuer, std::string_view subject, EVP_PKEY *key,
    bool is_ca, std::optional<int64_t> pathlen = std::nullopt) {
  UniquePtr<X509_NAME> issuer_name = MakeTestName(issuer);
  UniquePtr<X509_NAME> subject_name = MakeTestName(subject);
  UniquePtr<X509> cert(X509_new());
  UniquePtr<ASN1_INTEGER> serial(ASN1_INTEGER_new());
  if (issuer_name == nullptr || subject_name == nullptr || cert == nullptr ||
      serial == nullptr ||  //
      !X509_set_version(cert.get(), X509_VERSION_3) ||
      !ASN1_INTEGER_set_uint64(serial.get(), 42) ||
      !X509_set_serialNumber(cert.get(), serial.get()) ||
      !X509_set_issuer_name(cert.get(), issuer_name.get()) ||
      !X509_set_subject_name(cert.get(), subject_name.get()) ||
      !X509_set_pubkey(cert.get(), key) ||
      !ASN1_TIME_adj(X509_getm_notBefore(cert.get()), kReferenceTime, -1, 0) ||
      !ASN1_TIME_adj(X509_getm_notAfter(cert.get()), kReferenceTime, 1, 0)) {
    return nullptr;
  }
  UniquePtr<BASIC_CONSTRAINTS> bc(BASIC_CONSTRAINTS_new());
  if (!bc) {
    return nullptr;
  }
  bc->ca = is_ca ? ASN1_BOOLEAN_TRUE : ASN1_BOOLEAN_FALSE;
  if (pathlen.has_value()) {
    bc->pathlen = ASN1_INTEGER_new();
    if (bc->pathlen == nullptr ||
        !ASN1_INTEGER_set_int64(bc->pathlen, *pathlen)) {
      return nullptr;
    }
  }
  if (!X509_add1_ext_i2d(cert.get(), NID_basic_constraints, bc.get(),
                         /*crit=*/1, /*flags=*/0)) {
    return nullptr;
  }
  return cert;
}

static bool AddExtendedKeyUsage(X509 *x509, const std::vector<int> &eku_nids) {
  UniquePtr<STACK_OF(ASN1_OBJECT)> objs(sk_ASN1_OBJECT_new_null());
  if (objs == nullptr) {
    return false;
  }
  for (int nid : eku_nids) {
    if (!sk_ASN1_OBJECT_push(objs.get(), OBJ_nid2obj(nid))) {
      return false;
    }
  }
  return X509_add1_ext_i2d(x509, NID_ext_key_usage, objs.get(), /*crit=*/1,
                           /*flags=*/0);
}

enum class KeyUsage : int {
  kDigitalSignature = 0,
  kNonRepudiation = 1,
  kKeyEncipherment = 2,
  kDataEncipherment = 3,
  kKeyAgreement = 4,
  kKeyCertSign = 5,
  kCRLSign = 6,
  kEncipherOnly = 7,
  kDecipherOnly = 8,
};

static bool AddKeyUsage(X509 *x509, const std::vector<KeyUsage> usages) {
  UniquePtr<ASN1_BIT_STRING> str(ASN1_BIT_STRING_new());
  if (str == nullptr) {
    return false;
  }
  for (KeyUsage usage : usages) {
    if (!ASN1_BIT_STRING_set_bit(str.get(), static_cast<int>(usage), 1)) {
      return false;
    }
  }
  return X509_add1_ext_i2d(x509, NID_key_usage, str.get(), /*crit=*/1,
                           /*flags=*/0);
}

static bool AddSubjectKeyIdentifier(X509 *x509, Span<const uint8_t> key_id) {
  UniquePtr<ASN1_OCTET_STRING> oct(ASN1_OCTET_STRING_new());
  return oct != nullptr &&
         ASN1_STRING_set(oct.get(), key_id.data(), key_id.size()) &&
         X509_add1_ext_i2d(x509, NID_subject_key_identifier, oct.get(),
                           /*crit=*/0, /*flags=*/0);
}

static bool AddAuthorityKeyIdentifier(X509 *x509, Span<const uint8_t> key_id) {
  UniquePtr<AUTHORITY_KEYID> akid(AUTHORITY_KEYID_new());
  if (akid == nullptr) {
    return false;
  }
  akid->keyid = ASN1_OCTET_STRING_new();
  if (akid->keyid == nullptr ||
      !ASN1_STRING_set(akid->keyid, key_id.data(), key_id.size()) ||
      !X509_add1_ext_i2d(x509, NID_authority_key_identifier, akid.get(),
                         /*crit=*/0, /*flags=*/0)) {
    return false;
  }
  return true;
}

static bssl::UniquePtr<X509_CRL> MakeTestCRL(std::string_view issuer,
                                             int this_update_offset_day,
                                             int next_update_offset_day) {
  UniquePtr<X509_NAME> issuer_name = MakeTestName(issuer);
  UniquePtr<X509_CRL> crl(X509_CRL_new());
  UniquePtr<ASN1_TIME> this_update(ASN1_TIME_adj(
      nullptr, kReferenceTime, this_update_offset_day, /*offset_sec=*/0));
  UniquePtr<ASN1_TIME> next_update(ASN1_TIME_adj(
      nullptr, kReferenceTime, next_update_offset_day, /*offset_sec=*/0));
  if (crl == nullptr || issuer_name == nullptr || this_update == nullptr ||
      next_update == nullptr ||
      !X509_CRL_set_version(crl.get(), X509_CRL_VERSION_2) ||
      !X509_CRL_set_issuer_name(crl.get(), issuer_name.get()) ||
      // OpenSSL's API is named incorrectly. The field is called thisUpdate.
      !X509_CRL_set1_lastUpdate(crl.get(), this_update.get()) ||
      !X509_CRL_set1_nextUpdate(crl.get(), next_update.get())) {
    return nullptr;
  }

  return crl;
}

static bool AddRevokedSerialU64(X509_CRL *crl, uint64_t serial,
                                int offset_day) {
  UniquePtr<X509_REVOKED> rev(X509_REVOKED_new());
  UniquePtr<ASN1_INTEGER> serial_asn1(ASN1_INTEGER_new());
  UniquePtr<ASN1_TIME> rev_date(
      ASN1_TIME_adj(nullptr, kReferenceTime, offset_day, /*offset_sec=*/0));
  if (rev == nullptr || serial_asn1 == nullptr || rev_date == nullptr ||
      !ASN1_INTEGER_set_uint64(serial_asn1.get(), serial) ||
      !X509_REVOKED_set_serialNumber(rev.get(), serial_asn1.get()) ||
      !X509_REVOKED_set_revocationDate(rev.get(), rev_date.get()) ||
      !X509_CRL_add0_revoked(crl, rev.get())) {
    return false;
  }
  rev.release();  // X509_CRL_add0_revoked takes ownership on success.
  return true;
}

static bool AddAuthorityKeyIdentifier(X509_CRL *crl,
                                      Span<const uint8_t> key_id) {
  UniquePtr<AUTHORITY_KEYID> akid(AUTHORITY_KEYID_new());
  if (akid == nullptr) {
    return false;
  }
  akid->keyid = ASN1_OCTET_STRING_new();
  if (akid->keyid == nullptr ||
      !ASN1_STRING_set(akid->keyid, key_id.data(), key_id.size()) ||
      !X509_CRL_add1_ext_i2d(crl, NID_authority_key_identifier, akid.get(),
                             /*crit=*/0, /*flags=*/0)) {
    return false;
  }
  return true;
}

TEST(X509Test, NameConstraints) {
  enum class SpecialCase {
    // The constraint as excludedSubtrees is the opposite of permittedSubtrees.
    kNormal,

    // The constraint always fails as excludedSubtrees.
    kExcludedViolation,

    // The constraint fails as excludedSubtrees when the name is a DN attribute.
    kExcludedViolationIfDNAttribute,
  };

  UniquePtr<EVP_PKEY> key = PrivateKeyFromPEM(kP256Key);
  ASSERT_TRUE(key);

  const struct {
    int type;
    std::string name;
    std::string constraint;
    int permit_result;
    SpecialCase special_case = SpecialCase::kNormal;
  } kTests[] = {
      // Empty string matches everything.
      {GEN_DNS, "foo.example.com", "", X509_V_OK},
      // Name constraints match the entire subtree.
      {GEN_DNS, "foo.example.com", "example.com", X509_V_OK},
      {GEN_DNS, "foo.example.com", "EXAMPLE.COM", X509_V_OK},
      {GEN_DNS, "foo.example.com", "xample.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_DNS, "foo.example.com", "unrelated.much.longer.name.example",
       X509_V_ERR_PERMITTED_VIOLATION},
      // A leading dot means at least one component must be added.
      {GEN_DNS, "foo.example.com", ".example.com", X509_V_OK},
      {GEN_DNS, "foo.example.com", "foo.example.com", X509_V_OK},
      {GEN_DNS, "foo.example.com", ".foo.example.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_DNS, "foo.example.com", ".xample.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_DNS, "foo.example.com", ".unrelated.much.longer.name.example",
       X509_V_ERR_PERMITTED_VIOLATION},
      // Trailing dot is ignored.
      {GEN_DNS, "foo.example.com.", "example.com", X509_V_OK},
      {GEN_DNS, "foo.example.com", "example.com.", X509_V_OK},
      // NUL bytes, if not rejected, should not confuse the matching logic.
      {GEN_DNS, std::string({'a', '\0', 'a'}), std::string({'a', '\0', 'b'}),
       X509_V_ERR_PERMITTED_VIOLATION},

      // Wildcard CN matching.
      {GEN_DNS, "*.com", "foo.example.com", X509_V_ERR_PERMITTED_VIOLATION},
      // A foo.example.com permitted subtree does not permit *.example.com.
      // However, a foo.example.com excluded subtree does exclude *.example.com
      // because there is a partial overlap between the two.
      {GEN_DNS, "*.example.com", "foo.example.com",
       X509_V_ERR_PERMITTED_VIOLATION, SpecialCase::kExcludedViolation},
      {GEN_DNS, "*.foo.example.com", "foo.example.com", X509_V_OK},
      {GEN_DNS, "*.sub.foo.example.com", "foo.example.com", X509_V_OK},
      {GEN_DNS, "*.bar.example.com", "foo.example.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_DNS, "*.example.com", "net", X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_DNS, "*.example.com", "com", X509_V_OK},

      // Names must be emails.
      {GEN_EMAIL, "not-an-email.example", "not-an-email.example",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_EMAIL, "not@an@email.example", "an@email.example",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_EMAIL, "not@an@email.example", "email.example",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_EMAIL, "not-an-email.example@", "not-an-email.example@",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_EMAIL, "not-an-email.example@", "@",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_EMAIL, "not-an-email.example@", "",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      // Only ASCII emails are supported.
      {GEN_EMAIL, "bäd-chäräcter@not-an-email.example", "not-an-email.example",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      // Quoting is not supported.
      {GEN_EMAIL, "\"foo\"@not-an-email.example", "foo@not-an-email.example",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_EMAIL, "foo@not-an-email.example", "\"foo\"@not-an-email.example",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},

      // A leading dot matches all local names and all subdomains, but not the
      // domain itself.
      {GEN_EMAIL, "foo@bar.example.com", ".example.com", X509_V_OK},
      {GEN_EMAIL, "foo@bar.example.com", ".EXAMPLE.COM", X509_V_OK},
      {GEN_EMAIL, "foo@bar.example.com", ".bar.example.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_EMAIL, "foo@bar.example.com", "foo@.example.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_EMAIL, "foo@bar.example.com", "foo@.bar.example.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      // Without a leading dot, the host must match exactly.
      {GEN_EMAIL, "foo@example.com", "example.com", X509_V_OK},
      {GEN_EMAIL, "foo@example.com", "EXAMPLE.COM", X509_V_OK},
      {GEN_EMAIL, "foo@bar.example.com", "example.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      // If the constraint specifies a mailbox, it specifies the whole thing.
      // The localpart is usually handled case-sensitively, the domainpart
      // case-insensitively.
      {GEN_EMAIL, "foo@example.com", "foo@example.com", X509_V_OK},
      {GEN_EMAIL, "foo@example.com", "foo@EXAMPLE.COM", X509_V_OK},
      // In the special case of the email being supplied as a DN attribute,
      // compare the localpart case-insensitively too, but for exclusions only.
      {GEN_EMAIL, "foo@example.com", "FOO@example.com",
       X509_V_ERR_PERMITTED_VIOLATION,
       SpecialCase::kExcludedViolationIfDNAttribute},
      {GEN_EMAIL, "foo@example.com", "bar@example.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      // OpenSSL ignores a stray leading @. BoringSSL does not.
      {GEN_EMAIL, "foo@example.com", "@example.com",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_EMAIL, "foo@example.com", "@EXAMPLE.COM",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_EMAIL, "foo@bar.example.com", "@example.com",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},

      // Basic syntax check.
      {GEN_URI, "not-a-url", "not-a-url", X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo:not-a-url", "not-a-url",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo:/not-a-url", "not-a-url",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo:///not-a-url", "not-a-url",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo://:not-a-url", "not-a-url",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo://", "not-a-url", X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      // Reject URIs with userinfo.
      {GEN_URI, "foo://username:password@example.com/whatever", "example.com",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo://username@example.com/whatever", "example.com",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo://@example.com/whatever", "example.com",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo://misleading.com:443@example.com/whatever",
       "misleading.com", X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo://misleading.com:443@", "example.com",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      // Reject IP addresses.
      {GEN_URI, "foo://123.45.67.89", "example.com",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo://0xde.0xad.0xbe.0xef", "example.com",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo://example.com.0x", "example.com",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo://example.com.0xca", "example.com",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo://[1234:5678:90ab::1]", "example.com",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      // Don't reject domain names whose final component consists of hex digits.
      {GEN_URI, "foo://0xde.0xad.0xbe.ef", ".0xbe.ef", X509_V_OK},
      // Port number, if present, must contain only digits.
      {GEN_URI, "foo://example.com:a443", "example.com",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      // Empty host is a syntax error.
      {GEN_URI, "foo://", "example.com", X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo:///whatever", "example.com",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo://:443", "example.com",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo://.:443", "example.com",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      // Hosts are an exact match.
      {GEN_URI, "foo://example.com", "example.com", X509_V_OK},
      {GEN_URI, "foo://example.com:443", "example.com", X509_V_OK},
      {GEN_URI, "foo://example.com/whatever", "example.com", X509_V_OK},
      {GEN_URI, "foo://example.com?query", "example.com", X509_V_OK},
      {GEN_URI, "foo://example.com#fragment", "example.com", X509_V_OK},
      {GEN_URI, "foo://bar.example.com", "example.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_URI, "foo://bar.example.com:443", "example.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_URI, "foo://bar.example.com/whatever", "example.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_URI, "foo://bar.example.com", "xample.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_URI, "foo://bar.example.com:443", "xample.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_URI, "foo://bar.example.com/whatever", "xample.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_URI, "foo://example.com", "some-other-name.example",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_URI, "foo://example.com:443", "some-other-name.example",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_URI, "foo://example.com/whatever", "some-other-name.example",
       X509_V_ERR_PERMITTED_VIOLATION},
      // A leading dot allows components to be added.
      {GEN_URI, "foo://example.com", ".example.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_URI, "foo://example.com:443", ".example.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_URI, "foo://example.com/whatever", ".example.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_URI, "foo://bar.example.com", ".example.com", X509_V_OK},
      {GEN_URI, "foo://bar.example.com:443", ".example.com", X509_V_OK},
      {GEN_URI, "foo://bar.example.com/whatever", ".example.com", X509_V_OK},
      {GEN_URI, "foo://example.com", ".some-other-name.example",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_URI, "foo://example.com:443", ".some-other-name.example",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_URI, "foo://example.com/whatever", ".some-other-name.example",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_URI, "foo://example.com", ".xample.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_URI, "foo://example.com:443", ".xample.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      {GEN_URI, "foo://example.com/whatever", ".xample.com",
       X509_V_ERR_PERMITTED_VIOLATION},
      // Allow a single trailing dot representing the DNS common root.
      {GEN_URI, "foo://bar.example.com.", ".example.com", X509_V_OK},
      {GEN_URI, "foo://bar.example.com.", ".example.com.", X509_V_OK},
      {GEN_URI, "foo://bar.example.com", ".example.com.", X509_V_OK},
      {GEN_URI, "foo://bar.example.com.:443", ".example.com.", X509_V_OK},
      {GEN_URI, "foo://bar.example.com", "bar.example.com.", X509_V_OK},
      // Multiple trailing dots, or empty labels, are not allowed.
      {GEN_URI, "foo://bar.example.com..", ".example.com.",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo://bar..example.com.", ".example.com.",
       X509_V_ERR_UNSUPPORTED_NAME_SYNTAX},
      {GEN_URI, "foo://bar.example.com.", ".example.com..",
       X509_V_ERR_UNSUPPORTED_CONSTRAINT_SYNTAX},
      {GEN_URI, "foo://bar.example.com.", ".example..com.",
       X509_V_ERR_UNSUPPORTED_CONSTRAINT_SYNTAX},
      // Test name constraint parsing. The URI name constraint should be a valid
      // FQDN.
      {GEN_URI, "foo://example.com", "..example.com",
       X509_V_ERR_UNSUPPORTED_CONSTRAINT_SYNTAX},
      {GEN_URI, "foo://example.com:443", "example.com:443",
       X509_V_ERR_UNSUPPORTED_CONSTRAINT_SYNTAX},
  };
  for (const auto &t : kTests) {
    SCOPED_TRACE(t.type);
    SCOPED_TRACE(t.name);
    SCOPED_TRACE(t.constraint);

    for (bool use_attr : {false, true}) {
      SCOPED_TRACE(use_attr);
      if (use_attr) {
        if (t.type != GEN_EMAIL) {
          // DN attribute is only supported for emails.
          continue;
        }
      }
      for (bool exclude : {false, true}) {
        SCOPED_TRACE(exclude);

        UniquePtr<GENERAL_NAME> name = MakeGeneralName(t.type, t.name);
        ASSERT_TRUE(name);
        UniquePtr<GENERAL_NAMES> names(GENERAL_NAMES_new());
        ASSERT_TRUE(names);
        ASSERT_TRUE(PushToStack(names.get(), std::move(name)));

        UniquePtr<NAME_CONSTRAINTS> nc(NAME_CONSTRAINTS_new());
        ASSERT_TRUE(nc);
        STACK_OF(GENERAL_SUBTREE) **rule =
            exclude ? &nc->excludedSubtrees : &nc->permittedSubtrees;
        *rule = sk_GENERAL_SUBTREE_new_null();
        ASSERT_TRUE(*rule);
        UniquePtr<GENERAL_SUBTREE> subtree(GENERAL_SUBTREE_new());
        ASSERT_TRUE(subtree);
        GENERAL_NAME_free(subtree->base);
        subtree->base = MakeGeneralName(t.type, t.constraint).release();
        ASSERT_TRUE(subtree->base);
        ASSERT_TRUE(PushToStack(*rule, std::move(subtree)));

        UniquePtr<X509> root =
            MakeTestCert("Root", "Root", key.get(), /*is_ca=*/true);
        ASSERT_TRUE(root);
        ASSERT_TRUE(X509_add1_ext_i2d(root.get(), NID_name_constraints,
                                      nc.get(),
                                      /*crit=*/1, /*flags=*/0));
        ASSERT_TRUE(X509_sign(root.get(), key.get(), EVP_sha256()));

        UniquePtr<X509> leaf =
            MakeTestCert("Root", "Leaf", key.get(), /*is_ca=*/false);
        ASSERT_TRUE(leaf);
        if (use_attr) {
          UniquePtr<X509_NAME> subject(X509_NAME_new());
          ASSERT_TRUE(subject);
          ASSERT_TRUE(X509_NAME_add_entry_by_NID(
              subject.get(), NID_pkcs9_emailAddress, V_ASN1_IA5STRING,
              reinterpret_cast<const unsigned char *>(t.name.data()),
              t.name.size(), /*loc=*/-1, /*set=*/0));
          ASSERT_TRUE(X509_set_subject_name(leaf.get(), subject.get()));
        } else {
          ASSERT_TRUE(X509_add1_ext_i2d(leaf.get(), NID_subject_alt_name,
                                        names.get(),
                                        /*crit=*/0, /*flags=*/0));
        }
        ASSERT_TRUE(X509_sign(leaf.get(), key.get(), EVP_sha256()));

        int got_result = Verify(leaf.get(), {root.get()}, {}, {}, 0);

        int want_result = t.permit_result;
        if (exclude) {
          // By default, invert the sense when excluding.
          switch (t.permit_result) {
            case X509_V_OK:
              want_result = X509_V_ERR_EXCLUDED_VIOLATION;
              break;
            case X509_V_ERR_PERMITTED_VIOLATION:
              want_result = X509_V_OK;
              break;
          }

          // Handle special cases.
          switch (t.special_case) {
            case SpecialCase::kExcludedViolation:
              want_result = X509_V_ERR_EXCLUDED_VIOLATION;
              break;
            case SpecialCase::kExcludedViolationIfDNAttribute:
              if (use_attr) {
                want_result = X509_V_ERR_EXCLUDED_VIOLATION;
              }
              break;
            default:;
          }
        }
        EXPECT_EQ(want_result, got_result)
            << "got \"" << X509_verify_cert_error_string(got_result)
            << "\", want \"" << X509_verify_cert_error_string(want_result)
            << "\"";
      }
    }
  }
}

TEST(X509Test, PrintGeneralName) {
  // TODO(https://crbug.com/boringssl/430): Add more tests. Also fix the
  // external projects that use this to extract the SAN list and unexport.
  UniquePtr<GENERAL_NAME> gen = MakeGeneralName(GEN_DNS, "example.com");
  ASSERT_TRUE(gen);
  UniquePtr<STACK_OF(CONF_VALUE)> values(
      i2v_GENERAL_NAME(nullptr, gen.get(), nullptr));
  ASSERT_TRUE(values);
  ASSERT_EQ(1u, sk_CONF_VALUE_num(values.get()));
  const CONF_VALUE *value = sk_CONF_VALUE_value(values.get(), 0);
  EXPECT_STREQ(value->name, "DNS");
  EXPECT_STREQ(value->value, "example.com");
}

TEST(X509Test, TestPSS) {
  static const char *kGoodCerts[] = {
      "crypto/x509/test/pss_sha256.pem",
      "crypto/x509/test/pss_sha384.pem",
      "crypto/x509/test/pss_sha512.pem",
      // We accept inputs with and without explicit NULLs. See RFC 4055,
      // section 2.1.
      "crypto/x509/test/pss_sha256_omit_nulls.pem",
      // Although invalid, we tolerate an explicit trailerField value. See the
      // certificates in cl/362617931.
      "crypto/x509/test/pss_sha256_explicit_trailer.pem",
  };
  for (const char *path : kGoodCerts) {
    SCOPED_TRACE(path);
    UniquePtr<X509> cert = CertFromPEM(GetTestData(path));
    ASSERT_TRUE(cert);
    UniquePtr<EVP_PKEY> pkey(X509_get_pubkey(cert.get()));
    ASSERT_TRUE(pkey);
    EXPECT_TRUE(X509_verify(cert.get(), pkey.get()));
  }

  static const char *kBadCerts[] = {
      "crypto/x509/test/pss_sha1_explicit.pem",
      "crypto/x509/test/pss_sha1_mgf1_syntax_error.pem",
      "crypto/x509/test/pss_sha1.pem",
      "crypto/x509/test/pss_sha224.pem",
      "crypto/x509/test/pss_sha256_mgf1_sha384.pem",
      "crypto/x509/test/pss_sha256_mgf1_syntax_error.pem",
      "crypto/x509/test/pss_sha256_salt_overflow.pem",
      "crypto/x509/test/pss_sha256_salt31.pem",
      "crypto/x509/test/pss_sha256_unknown_mgf.pem",
      "crypto/x509/test/pss_sha256_wrong_trailer.pem",
  };
  for (const char *path : kBadCerts) {
    SCOPED_TRACE(path);
    UniquePtr<X509> cert = CertFromPEM(GetTestData(path));
    ASSERT_TRUE(cert);
    UniquePtr<EVP_PKEY> pkey(X509_get_pubkey(cert.get()));
    ASSERT_TRUE(pkey);
    EXPECT_FALSE(X509_verify(cert.get(), pkey.get()));
    EXPECT_TRUE(ErrorsAreAndClear({{std::nullopt, std::nullopt}}));
  }
}

TEST(X509Test, TestPSSBadParameters) {
  UniquePtr<X509> cert(CertFromPEM(kBadPSSCertPEM));
  ASSERT_TRUE(cert);

  UniquePtr<EVP_PKEY> pkey(X509_get_pubkey(cert.get()));
  ASSERT_TRUE(pkey);

  ASSERT_FALSE(X509_verify(cert.get(), pkey.get()));
  ERR_clear_error();
}

TEST(X509Test, TestEd25519) {
  UniquePtr<X509> cert(CertFromPEM(kEd25519Cert));
  ASSERT_TRUE(cert);

  UniquePtr<EVP_PKEY> pkey(X509_get_pubkey(cert.get()));
  ASSERT_TRUE(pkey);

  ASSERT_TRUE(X509_verify(cert.get(), pkey.get()));
}

TEST(X509Test, TestEd25519BadParameters) {
  UniquePtr<X509> cert(CertFromPEM(kEd25519CertNull));
  ASSERT_TRUE(cert);

  UniquePtr<EVP_PKEY> pkey(X509_get_pubkey(cert.get()));
  ASSERT_TRUE(pkey);

  ASSERT_FALSE(X509_verify(cert.get(), pkey.get()));

  EXPECT_TRUE(
      ErrorEquals(ERR_get_error(), ERR_LIB_X509, X509_R_INVALID_PARAMETER));
  ERR_clear_error();
}

TEST(X509Test, TestX25519) {
  UniquePtr<X509> cert(CertFromPEM(kX25519Cert));
  ASSERT_TRUE(cert);

  UniquePtr<EVP_PKEY> pkey(X509_get_pubkey(cert.get()));
  ASSERT_TRUE(pkey);

  EXPECT_EQ(EVP_PKEY_id(pkey.get()), EVP_PKEY_X25519);

  constexpr uint8_t kExpectedPublicValue[] = {
      0x85, 0x20, 0xf0, 0x09, 0x89, 0x30, 0xa7, 0x54, 0x74, 0x8b, 0x7d,
      0xdc, 0xb4, 0x3e, 0xf7, 0x5a, 0x0d, 0xbf, 0x3a, 0x0d, 0x26, 0x38,
      0x1a, 0xf4, 0xeb, 0xa4, 0xa9, 0x8e, 0xaa, 0x9b, 0x4e, 0x6a,
  };
  uint8_t public_value[sizeof(kExpectedPublicValue)];
  size_t public_value_size = sizeof(public_value);
  ASSERT_TRUE(EVP_PKEY_get_raw_public_key(pkey.get(), public_value,
                                          &public_value_size));
  EXPECT_EQ(Bytes(kExpectedPublicValue),
            Bytes(public_value, public_value_size));
}

TEST(X509Test, TestMlDsa65) {
  UniquePtr<X509> cert(CertFromPEM(kMlDsa65Cert));
  ASSERT_TRUE(cert);

  UniquePtr<EVP_PKEY> pkey(X509_get_pubkey(cert.get()));
  ASSERT_TRUE(pkey);

  ASSERT_TRUE(X509_verify(cert.get(), pkey.get()));
}

TEST(X509Test, TestMlDsa65BadParameters) {
  UniquePtr<X509> cert(CertFromPEM(kMlDsa65CertNull));
  ASSERT_TRUE(cert);

  UniquePtr<EVP_PKEY> pkey(X509_get_pubkey(cert.get()));
  ASSERT_TRUE(pkey);

  ASSERT_FALSE(X509_verify(cert.get(), pkey.get()));

  EXPECT_TRUE(
      ErrorEquals(ERR_get_error(), ERR_LIB_X509, X509_R_INVALID_PARAMETER));
  ERR_clear_error();
}

static bssl::UniquePtr<X509> ReencodeCertificate(X509 *cert) {
  uint8_t *der = nullptr;
  int len = i2d_X509(cert, &der);
  UniquePtr<uint8_t> free_der(der);
  if (len <= 0) {
    return nullptr;
  }

  const uint8_t *inp = der;
  return UniquePtr<X509>(d2i_X509(nullptr, &inp, len));
}

static bssl::UniquePtr<X509> ReencodeCertificateWithAlgorithms(
    X509 *cert, Span<const EVP_PKEY_ALG *const> algs) {
  uint8_t *der = nullptr;
  int len = i2d_X509(cert, &der);
  UniquePtr<uint8_t> free_der(der);
  if (len <= 0) {
    return nullptr;
  }

  UniquePtr<CRYPTO_BUFFER> buf(CRYPTO_BUFFER_new(der, len, nullptr));
  if (buf == nullptr) {
    return nullptr;
  }
  return UniquePtr<X509>(
      X509_parse_with_algorithms(buf.get(), algs.data(), algs.size()));
}

static bssl::UniquePtr<X509_CRL> ReencodeCRL(X509_CRL *crl) {
  uint8_t *der = nullptr;
  int len = i2d_X509_CRL(crl, &der);
  UniquePtr<uint8_t> free_der(der);
  if (len <= 0) {
    return nullptr;
  }

  const uint8_t *inp = der;
  return UniquePtr<X509_CRL>(d2i_X509_CRL(nullptr, &inp, len));
}

static bssl::UniquePtr<X509_REQ> ReencodeCSR(X509_REQ *req) {
  uint8_t *der = nullptr;
  int len = i2d_X509_REQ(req, &der);
  UniquePtr<uint8_t> free_der(der);
  if (len <= 0) {
    return nullptr;
  }

  const uint8_t *inp = der;
  return UniquePtr<X509_REQ>(d2i_X509_REQ(nullptr, &inp, len));
}

static bool SignatureRoundTrips(EVP_MD_CTX *md_ctx, EVP_PKEY *pkey) {
  // Make a certificate like signed with `md_ctx`'s settings.'
  UniquePtr<X509> cert(CertFromPEM(kLeafPEM));
  if (!cert || !X509_sign_ctx(cert.get(), md_ctx)) {
    return false;
  }

  // Ensure that `pkey` may still be used to verify the resulting signature. All
  // settings in `md_ctx` must have been serialized appropriately.
  if (!X509_verify(cert.get(), pkey)) {
    return false;
  }

  // Re-encode the certificate. X509 objects contain a cached TBSCertificate
  // encoding and `X509_sign_ctx` should have dropped that cache.
  UniquePtr<X509> copy = ReencodeCertificate(cert.get());
  return copy && X509_verify(copy.get(), pkey);
}

TEST(X509Test, RSASign) {
  UniquePtr<EVP_PKEY> pkey(PrivateKeyFromPEM(kRSAKey));
  ASSERT_TRUE(pkey);
  // Test PKCS#1 v1.5.
  ScopedEVP_MD_CTX md_ctx;
  ASSERT_TRUE(EVP_DigestSignInit(md_ctx.get(), nullptr, EVP_sha256(), nullptr,
                                 pkey.get()));
  ASSERT_TRUE(SignatureRoundTrips(md_ctx.get(), pkey.get()));

  // RSA-PSS with salt length matching hash length should work when passing in
  // `RSA_PSS_SALTLEN_DIGEST` or the value explicitly.
  md_ctx.Reset();
  EVP_PKEY_CTX *pkey_ctx;
  ASSERT_TRUE(EVP_DigestSignInit(md_ctx.get(), &pkey_ctx, EVP_sha256(), nullptr,
                                 pkey.get()));
  ASSERT_TRUE(EVP_PKEY_CTX_set_rsa_padding(pkey_ctx, RSA_PKCS1_PSS_PADDING));
  ASSERT_TRUE(
      EVP_PKEY_CTX_set_rsa_pss_saltlen(pkey_ctx, RSA_PSS_SALTLEN_DIGEST));
  ASSERT_TRUE(SignatureRoundTrips(md_ctx.get(), pkey.get()));

  md_ctx.Reset();
  ASSERT_TRUE(EVP_DigestSignInit(md_ctx.get(), &pkey_ctx, EVP_sha256(), nullptr,
                                 pkey.get()));
  ASSERT_TRUE(EVP_PKEY_CTX_set_rsa_padding(pkey_ctx, RSA_PKCS1_PSS_PADDING));
  ASSERT_TRUE(EVP_PKEY_CTX_set_rsa_pss_saltlen(pkey_ctx, 32));
  ASSERT_TRUE(SignatureRoundTrips(md_ctx.get(), pkey.get()));

  // RSA-PSS with SHA-1 is not supported.
  md_ctx.Reset();
  ASSERT_TRUE(EVP_DigestSignInit(md_ctx.get(), &pkey_ctx, EVP_sha1(), nullptr,
                                 pkey.get()));
  ASSERT_TRUE(EVP_PKEY_CTX_set_rsa_padding(pkey_ctx, RSA_PKCS1_PSS_PADDING));
  ASSERT_TRUE(
      EVP_PKEY_CTX_set_rsa_pss_saltlen(pkey_ctx, RSA_PSS_SALTLEN_DIGEST));
  UniquePtr<X509> cert = CertFromPEM(kLeafPEM);
  ASSERT_TRUE(cert);
  EXPECT_FALSE(X509_sign_ctx(cert.get(), md_ctx.get()));

  // RSA-PSS with mismatched hashes is not supported.
  md_ctx.Reset();
  ASSERT_TRUE(EVP_DigestSignInit(md_ctx.get(), &pkey_ctx, EVP_sha256(), nullptr,
                                 pkey.get()));
  ASSERT_TRUE(EVP_PKEY_CTX_set_rsa_padding(pkey_ctx, RSA_PKCS1_PSS_PADDING));
  ASSERT_TRUE(
      EVP_PKEY_CTX_set_rsa_pss_saltlen(pkey_ctx, RSA_PSS_SALTLEN_DIGEST));
  ASSERT_TRUE(EVP_PKEY_CTX_set_rsa_mgf1_md(pkey_ctx, EVP_sha512()));
  cert = CertFromPEM(kLeafPEM);
  ASSERT_TRUE(cert);
  EXPECT_FALSE(X509_sign_ctx(cert.get(), md_ctx.get()));

  // RSA-PSS with the wrong salt length is not supported.
  md_ctx.Reset();
  ASSERT_TRUE(EVP_DigestSignInit(md_ctx.get(), &pkey_ctx, EVP_sha256(), nullptr,
                                 pkey.get()));
  ASSERT_TRUE(EVP_PKEY_CTX_set_rsa_padding(pkey_ctx, RSA_PKCS1_PSS_PADDING));
  ASSERT_TRUE(EVP_PKEY_CTX_set_rsa_pss_saltlen(pkey_ctx, 33));
  cert = CertFromPEM(kLeafPEM);
  ASSERT_TRUE(cert);
  EXPECT_FALSE(X509_sign_ctx(cert.get(), md_ctx.get()));
}

// Test the APIs for signing a certificate, particularly whether they correctly
// handle the TBSCertificate cache.
TEST(X509Test, SignCertificate) {
  const int kSignatureNID = NID_sha384WithRSAEncryption;
  const EVP_MD *kSignatureHash = EVP_sha384();

  UniquePtr<EVP_PKEY> pkey(PrivateKeyFromPEM(kRSAKey));
  ASSERT_TRUE(pkey);
  UniquePtr<X509_ALGOR> algor(X509_ALGOR_new());
  ASSERT_TRUE(algor);
  ASSERT_TRUE(X509_ALGOR_set0(algor.get(), OBJ_nid2obj(kSignatureNID),
                              V_ASN1_NULL, nullptr));

  // Test both signing with `X509_sign` and constructing a signature manually.
  for (bool sign_manual : {true, false}) {
    SCOPED_TRACE(sign_manual);

    // Test certificates made both from other certificates and `X509_new`, in
    // case there are bugs in filling in fields from different states. (Parsed
    // certificates contain a TBSCertificate cache, and `X509_new` initializes
    // fields based on complex ASN.1 template logic.)
    for (bool new_cert : {true, false}) {
      SCOPED_TRACE(new_cert);

      UniquePtr<X509> cert;
      if (new_cert) {
        cert.reset(X509_new());
        ASSERT_TRUE(cert);
        // Fill in some fields for the certificate arbitrarily.
        EXPECT_TRUE(X509_set_version(cert.get(), X509_VERSION_3));
        EXPECT_TRUE(
            ASN1_INTEGER_set_int64(X509_get_serialNumber(cert.get()), 1));
        EXPECT_TRUE(X509_gmtime_adj(X509_getm_notBefore(cert.get()), 0));
        EXPECT_TRUE(
            X509_gmtime_adj(X509_getm_notAfter(cert.get()), 60 * 60 * 24));
        X509_NAME *subject = X509_get_subject_name(cert.get());
        X509_NAME_add_entry_by_txt(subject, "CN", MBSTRING_ASC,
                                   reinterpret_cast<const uint8_t *>("Test"),
                                   -1, -1, 0);
        EXPECT_TRUE(X509_set_issuer_name(cert.get(), subject));
        EXPECT_TRUE(X509_set_pubkey(cert.get(), pkey.get()));
      } else {
        // Extract fields from a parsed certificate.
        cert = CertFromPEM(kLeafPEM);
        ASSERT_TRUE(cert);

        // We should test with a different algorithm from what is already in the
        // certificate.
        EXPECT_NE(kSignatureNID, X509_get_signature_nid(cert.get()));
      }

      if (sign_manual) {
        // Fill in the signature algorithm.
        ASSERT_TRUE(X509_set1_signature_algo(cert.get(), algor.get()));

        // Extract the TBSCertificate.
        uint8_t *tbs_cert = nullptr;
        int tbs_cert_len = i2d_re_X509_tbs(cert.get(), &tbs_cert);
        UniquePtr<uint8_t> free_tbs_cert(tbs_cert);
        ASSERT_GT(tbs_cert_len, 0);

        // Generate a signature externally and fill it in.
        ScopedEVP_MD_CTX md_ctx;
        ASSERT_TRUE(EVP_DigestSignInit(md_ctx.get(), nullptr, kSignatureHash,
                                       nullptr, pkey.get()));
        size_t sig_len;
        ASSERT_TRUE(EVP_DigestSign(md_ctx.get(), nullptr, &sig_len, tbs_cert,
                                   tbs_cert_len));
        std::vector<uint8_t> sig(sig_len);
        ASSERT_TRUE(EVP_DigestSign(md_ctx.get(), sig.data(), &sig_len, tbs_cert,
                                   tbs_cert_len));
        sig.resize(sig_len);
        ASSERT_TRUE(
            X509_set1_signature_value(cert.get(), sig.data(), sig.size()));
      } else {
        int ret = X509_sign(cert.get(), pkey.get(), EVP_sha384());
        ASSERT_GT(ret, 0);
        // `X509_sign` returns the length of the signature on success.
        const ASN1_BIT_STRING *sig;
        X509_get0_signature(&sig, /*out_alg=*/nullptr, cert.get());
        EXPECT_EQ(ret, ASN1_STRING_length(sig));
      }

      // Check the signature.
      EXPECT_TRUE(X509_verify(cert.get(), pkey.get()));

      // Re-encode the certificate. X509 objects contain a cached TBSCertificate
      // encoding and re-signing should have dropped that cache.
      UniquePtr<X509> copy = ReencodeCertificate(cert.get());
      ASSERT_TRUE(copy);
      EXPECT_TRUE(X509_verify(copy.get(), pkey.get()));
    }
  }
}

// Test the APIs for signing a CRL, particularly whether they correctly handle
// the TBSCertList cache.
TEST(X509Test, SignCRL) {
  const int kSignatureNID = NID_sha384WithRSAEncryption;
  const EVP_MD *kSignatureHash = EVP_sha384();

  UniquePtr<EVP_PKEY> pkey(PrivateKeyFromPEM(kRSAKey));
  ASSERT_TRUE(pkey);
  UniquePtr<X509_ALGOR> algor(X509_ALGOR_new());
  ASSERT_TRUE(algor);
  ASSERT_TRUE(X509_ALGOR_set0(algor.get(), OBJ_nid2obj(kSignatureNID),
                              V_ASN1_NULL, nullptr));

  // Test both signing with `X509_CRL_sign` and constructing a signature
  // manually.
  for (bool sign_manual : {true, false}) {
    SCOPED_TRACE(sign_manual);

    // Test CRLs made both from other CRLs and `X509_CRL_new`, in case there are
    // bugs in filling in fields from different states. (Parsed CRLs contain a
    // TBSCertList cache, and `X509_CRL_new` initializes fields based on complex
    // ASN.1 template logic.)
    for (bool new_crl : {true, false}) {
      SCOPED_TRACE(new_crl);

      UniquePtr<X509_CRL> crl;
      if (new_crl) {
        crl.reset(X509_CRL_new());
        ASSERT_TRUE(crl);
        // Fill in some fields for the certificate arbitrarily.
        ASSERT_TRUE(X509_CRL_set_version(crl.get(), X509_CRL_VERSION_2));
        UniquePtr<ASN1_TIME> last_update(ASN1_TIME_new());
        ASSERT_TRUE(last_update);
        ASSERT_TRUE(ASN1_TIME_set_posix(last_update.get(), kReferenceTime));
        ASSERT_TRUE(X509_CRL_set1_lastUpdate(crl.get(), last_update.get()));
        UniquePtr<X509_NAME> issuer(X509_NAME_new());
        ASSERT_TRUE(issuer);
        ASSERT_TRUE(X509_NAME_add_entry_by_txt(
            issuer.get(), "CN", MBSTRING_ASC,
            reinterpret_cast<const uint8_t *>("Test"), -1, -1, 0));
        EXPECT_TRUE(X509_CRL_set_issuer_name(crl.get(), issuer.get()));
      } else {
        // Extract fields from a parsed CRL.
        crl = CRLFromPEM(kBasicCRL);
        ASSERT_TRUE(crl);

        // We should test with a different algorithm from what is already in the
        // CRL.
        EXPECT_NE(kSignatureNID, X509_CRL_get_signature_nid(crl.get()));
      }

      if (sign_manual) {
        // Fill in the signature algorithm.
        ASSERT_TRUE(X509_CRL_set1_signature_algo(crl.get(), algor.get()));

        // Extract the TBSCertList.
        uint8_t *tbs = nullptr;
        int tbs_len = i2d_re_X509_CRL_tbs(crl.get(), &tbs);
        UniquePtr<uint8_t> free_tbs(tbs);
        ASSERT_GT(tbs_len, 0);

        // Generate a signature externally and fill it in.
        ScopedEVP_MD_CTX md_ctx;
        ASSERT_TRUE(EVP_DigestSignInit(md_ctx.get(), nullptr, kSignatureHash,
                                       nullptr, pkey.get()));
        size_t sig_len;
        ASSERT_TRUE(
            EVP_DigestSign(md_ctx.get(), nullptr, &sig_len, tbs, tbs_len));
        std::vector<uint8_t> sig(sig_len);
        ASSERT_TRUE(
            EVP_DigestSign(md_ctx.get(), sig.data(), &sig_len, tbs, tbs_len));
        sig.resize(sig_len);
        ASSERT_TRUE(
            X509_CRL_set1_signature_value(crl.get(), sig.data(), sig.size()));
      } else {
        ASSERT_TRUE(X509_CRL_sign(crl.get(), pkey.get(), EVP_sha384()));
      }

      // Check the signature.
      EXPECT_TRUE(X509_CRL_verify(crl.get(), pkey.get()));

      // Re-encode the CRL. X509_CRL objects contain a cached TBSCertList
      // encoding and re-signing should have dropped that cache.
      UniquePtr<X509_CRL> copy = ReencodeCRL(crl.get());
      ASSERT_TRUE(copy);
      EXPECT_TRUE(X509_CRL_verify(copy.get(), pkey.get()));
    }
  }
}

static const char kTestCSR[] = R"(
-----BEGIN CERTIFICATE REQUEST-----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-----END CERTIFICATE REQUEST-----
)";

// Test the APIs for signing a CSR, particularly whether they correctly handle
// the CertificationRequestInfo cache.
TEST(X509Test, SignCSR) {
  const int kSignatureNID = NID_sha384WithRSAEncryption;
  const EVP_MD *kSignatureHash = EVP_sha384();

  UniquePtr<EVP_PKEY> pkey(PrivateKeyFromPEM(kRSAKey));
  ASSERT_TRUE(pkey);
  UniquePtr<X509_ALGOR> algor(X509_ALGOR_new());
  ASSERT_TRUE(algor);
  ASSERT_TRUE(X509_ALGOR_set0(algor.get(), OBJ_nid2obj(kSignatureNID),
                              V_ASN1_NULL, nullptr));

  // Test both signing with `X509_REQ_sign` and constructing a signature
  // manually.
  for (bool sign_manual : {true, false}) {
    SCOPED_TRACE(sign_manual);

    // Test CSRs made both from other CSRs and `X509_REQ_new`, in case there are
    // bugs in filling in fields from different states. (Parsed CSRs contain a
    // CertificationRequestInfo cache, and `X509_REQ_new` initializes fields
    // based on complex ASN.1 template logic.)
    for (bool new_csr : {true, false}) {
      SCOPED_TRACE(new_csr);

      UniquePtr<X509_REQ> csr;
      if (new_csr) {
        csr.reset(X509_REQ_new());
        ASSERT_TRUE(csr);
        UniquePtr<X509_NAME> subject(X509_NAME_new());
        ASSERT_TRUE(subject);
        ASSERT_TRUE(X509_NAME_add_entry_by_txt(
            subject.get(), "CN", MBSTRING_ASC,
            reinterpret_cast<const uint8_t *>("New CSR"), -1, -1, 0));
        EXPECT_TRUE(X509_REQ_set_subject_name(csr.get(), subject.get()));
      } else {
        // Extract fields from a parsed CSR.
        csr = CSRFromPEM(kTestCSR);
        ASSERT_TRUE(csr);
      }

      // Override the public key from the CSR unconditionally. Unlike
      // certificates and CRLs, CSRs do not contain a signed copy of the
      // signature algorithm, so we use a different field to confirm
      // `i2d_re_X509_REQ_tbs` clears the cache as expected.
      EXPECT_TRUE(X509_REQ_set_pubkey(csr.get(), pkey.get()));

      if (sign_manual) {
        // Fill in the signature algorithm.
        ASSERT_TRUE(X509_REQ_set1_signature_algo(csr.get(), algor.get()));

        // Extract the CertificationRequestInfo.
        uint8_t *tbs = nullptr;
        int tbs_len = i2d_re_X509_REQ_tbs(csr.get(), &tbs);
        UniquePtr<uint8_t> free_tbs(tbs);
        ASSERT_GT(tbs_len, 0);

        // Generate a signature externally and fill it in.
        ScopedEVP_MD_CTX md_ctx;
        ASSERT_TRUE(EVP_DigestSignInit(md_ctx.get(), nullptr, kSignatureHash,
                                       nullptr, pkey.get()));
        size_t sig_len;
        ASSERT_TRUE(
            EVP_DigestSign(md_ctx.get(), nullptr, &sig_len, tbs, tbs_len));
        std::vector<uint8_t> sig(sig_len);
        ASSERT_TRUE(
            EVP_DigestSign(md_ctx.get(), sig.data(), &sig_len, tbs, tbs_len));
        sig.resize(sig_len);
        ASSERT_TRUE(
            X509_REQ_set1_signature_value(csr.get(), sig.data(), sig.size()));
      } else {
        ASSERT_TRUE(X509_REQ_sign(csr.get(), pkey.get(), EVP_sha384()));
      }

      // Check the signature.
      EXPECT_TRUE(X509_REQ_verify(csr.get(), pkey.get()));

      // Re-encode the CSR. X509_REQ objects contain a cached
      // CertificationRequestInfo encoding and re-signing should have dropped
      // that cache.
      UniquePtr<X509_REQ> copy = ReencodeCSR(csr.get());
      ASSERT_TRUE(copy);
      EXPECT_TRUE(X509_REQ_verify(copy.get(), pkey.get()));

      // Check the signature was over the new public key.
      UniquePtr<EVP_PKEY> copy_pubkey(X509_REQ_get_pubkey(copy.get()));
      ASSERT_TRUE(copy_pubkey);
      EXPECT_EQ(1, EVP_PKEY_eq(pkey.get(), copy_pubkey.get()));
    }
  }
}

// The `*_sign_ctx` APIs implicitly call `EVP_MD_CTX_cleanup` on return, on both
// success and failure. Some callers rely on this to avoid a memory leak. These
// tests rely on ASan to detect leaks. Test failure by using unsupported RSA-PSS
// parameters.
TEST(X509Test, SignImplicitCleanup) {
  UniquePtr<EVP_PKEY> pkey(PrivateKeyFromPEM(kRSAKey));
  ASSERT_TRUE(pkey);

  UniquePtr<X509> cert = CertFromPEM(kLeafPEM);
  ASSERT_TRUE(cert);
  {
    EVP_MD_CTX ctx;
    EVP_MD_CTX_init(&ctx);
    ASSERT_TRUE(
        EVP_DigestSignInit(&ctx, nullptr, EVP_sha256(), nullptr, pkey.get()));
    EXPECT_TRUE(X509_sign_ctx(cert.get(), &ctx));
  }
  {
    EVP_MD_CTX ctx;
    EVP_MD_CTX_init(&ctx);
    EVP_PKEY_CTX *pkey_ctx;
    ASSERT_TRUE(
        EVP_DigestSignInit(&ctx, &pkey_ctx, EVP_sha256(), nullptr, pkey.get()));
    ASSERT_TRUE(EVP_PKEY_CTX_set_rsa_padding(pkey_ctx, RSA_PKCS1_PSS_PADDING));
    ASSERT_TRUE(EVP_PKEY_CTX_set_rsa_pss_saltlen(pkey_ctx, 33));
    EXPECT_FALSE(X509_sign_ctx(cert.get(), &ctx));
  }

  UniquePtr<X509_CRL> crl = CRLFromPEM(kBasicCRL);
  ASSERT_TRUE(crl);
  {
    EVP_MD_CTX ctx;
    EVP_MD_CTX_init(&ctx);
    ASSERT_TRUE(
        EVP_DigestSignInit(&ctx, nullptr, EVP_sha256(), nullptr, pkey.get()));
    EXPECT_TRUE(X509_CRL_sign_ctx(crl.get(), &ctx));
  }
  {
    EVP_MD_CTX ctx;
    EVP_MD_CTX_init(&ctx);
    EVP_PKEY_CTX *pkey_ctx;
    ASSERT_TRUE(
        EVP_DigestSignInit(&ctx, &pkey_ctx, EVP_sha256(), nullptr, pkey.get()));
    ASSERT_TRUE(EVP_PKEY_CTX_set_rsa_padding(pkey_ctx, RSA_PKCS1_PSS_PADDING));
    ASSERT_TRUE(EVP_PKEY_CTX_set_rsa_pss_saltlen(pkey_ctx, 33));
    EXPECT_FALSE(X509_CRL_sign_ctx(crl.get(), &ctx));
  }

  UniquePtr<X509_REQ> csr = CSRFromPEM(kTestCSR);
  ASSERT_TRUE(csr);
  {
    EVP_MD_CTX ctx;
    EVP_MD_CTX_init(&ctx);
    ASSERT_TRUE(
        EVP_DigestSignInit(&ctx, nullptr, EVP_sha256(), nullptr, pkey.get()));
    EXPECT_TRUE(X509_REQ_sign_ctx(csr.get(), &ctx));
  }
  {
    EVP_MD_CTX ctx;
    EVP_MD_CTX_init(&ctx);
    EVP_PKEY_CTX *pkey_ctx;
    ASSERT_TRUE(
        EVP_DigestSignInit(&ctx, &pkey_ctx, EVP_sha256(), nullptr, pkey.get()));
    ASSERT_TRUE(EVP_PKEY_CTX_set_rsa_padding(pkey_ctx, RSA_PKCS1_PSS_PADDING));
    ASSERT_TRUE(EVP_PKEY_CTX_set_rsa_pss_saltlen(pkey_ctx, 33));
    EXPECT_FALSE(X509_REQ_sign_ctx(csr.get(), &ctx));
  }
}

TEST(X509Test, Ed25519Sign) {
  uint8_t pub_bytes[32], priv_bytes[64];
  ED25519_keypair(pub_bytes, priv_bytes);

  UniquePtr<EVP_PKEY> pub(
      EVP_PKEY_from_raw_public_key(EVP_pkey_ed25519(), pub_bytes, 32));
  ASSERT_TRUE(pub);
  UniquePtr<EVP_PKEY> priv(
      EVP_PKEY_from_raw_private_key(EVP_pkey_ed25519(), priv_bytes, 32));
  ASSERT_TRUE(priv);

  ScopedEVP_MD_CTX md_ctx;
  ASSERT_TRUE(
      EVP_DigestSignInit(md_ctx.get(), nullptr, nullptr, nullptr, priv.get()));
  ASSERT_TRUE(SignatureRoundTrips(md_ctx.get(), pub.get()));
}

TEST(X509Test, MlDsa44Sign) {
  std::vector<uint8_t> pub_bytes(MLDSA44_PUBLIC_KEY_BYTES);
  std::vector<uint8_t> seed_bytes(MLDSA_SEED_BYTES);
  auto priv_key = std::make_unique<MLDSA44_private_key>();
  ASSERT_EQ(1, MLDSA44_generate_key(pub_bytes.data(), seed_bytes.data(),
                                    priv_key.get()));

  UniquePtr<EVP_PKEY> pub(EVP_PKEY_from_raw_public_key(
      EVP_pkey_ml_dsa_44(), pub_bytes.data(), MLDSA44_PUBLIC_KEY_BYTES));
  ASSERT_TRUE(pub);
  UniquePtr<EVP_PKEY> priv(EVP_PKEY_from_private_seed(
      EVP_pkey_ml_dsa_44(), seed_bytes.data(), MLDSA_SEED_BYTES));
  ASSERT_TRUE(priv);

  ScopedEVP_MD_CTX md_ctx;
  ASSERT_TRUE(
      EVP_DigestSignInit(md_ctx.get(), nullptr, nullptr, nullptr, priv.get()));
  ASSERT_TRUE(SignatureRoundTrips(md_ctx.get(), pub.get()));
}

TEST(X509Test, MlDsa65Sign) {
  std::vector<uint8_t> pub_bytes(MLDSA65_PUBLIC_KEY_BYTES);
  std::vector<uint8_t> seed_bytes(MLDSA_SEED_BYTES);
  auto priv_key = std::make_unique<MLDSA65_private_key>();
  ASSERT_EQ(1, MLDSA65_generate_key(pub_bytes.data(), seed_bytes.data(),
                                    priv_key.get()));

  UniquePtr<EVP_PKEY> pub(EVP_PKEY_from_raw_public_key(
      EVP_pkey_ml_dsa_65(), pub_bytes.data(), MLDSA65_PUBLIC_KEY_BYTES));
  ASSERT_TRUE(pub);
  UniquePtr<EVP_PKEY> priv(EVP_PKEY_from_private_seed(
      EVP_pkey_ml_dsa_65(), seed_bytes.data(), MLDSA_SEED_BYTES));
  ASSERT_TRUE(priv);

  ScopedEVP_MD_CTX md_ctx;
  ASSERT_TRUE(
      EVP_DigestSignInit(md_ctx.get(), nullptr, nullptr, nullptr, priv.get()));
  ASSERT_TRUE(SignatureRoundTrips(md_ctx.get(), pub.get()));
}

TEST(X509Test, MlDsa87Sign) {
  std::vector<uint8_t> pub_bytes(MLDSA87_PUBLIC_KEY_BYTES);
  std::vector<uint8_t> seed_bytes(MLDSA_SEED_BYTES);
  auto priv_key = std::make_unique<MLDSA87_private_key>();
  ASSERT_EQ(1, MLDSA87_generate_key(pub_bytes.data(), seed_bytes.data(),
                                    priv_key.get()));

  UniquePtr<EVP_PKEY> pub(EVP_PKEY_from_raw_public_key(
      EVP_pkey_ml_dsa_87(), pub_bytes.data(), MLDSA87_PUBLIC_KEY_BYTES));
  ASSERT_TRUE(pub);
  UniquePtr<EVP_PKEY> priv(EVP_PKEY_from_private_seed(
      EVP_pkey_ml_dsa_87(), seed_bytes.data(), MLDSA_SEED_BYTES));
  ASSERT_TRUE(priv);

  ScopedEVP_MD_CTX md_ctx;
  ASSERT_TRUE(
      EVP_DigestSignInit(md_ctx.get(), nullptr, nullptr, nullptr, priv.get()));
  ASSERT_TRUE(SignatureRoundTrips(md_ctx.get(), pub.get()));
}

static bool PEMToDER(UniquePtr<uint8_t> *out, size_t *out_len,
                     const char *pem) {
  UniquePtr<BIO> bio(BIO_new_mem_buf(pem, strlen(pem)));
  if (!bio) {
    return false;
  }

  char *name, *header;
  uint8_t *data;
  long data_len;
  if (!PEM_read_bio(bio.get(), &name, &header, &data, &data_len)) {
    fprintf(stderr, "failed to read PEM data.\n");
    return false;
  }
  OPENSSL_free(name);
  OPENSSL_free(header);

  out->reset(data);
  *out_len = data_len;

  return true;
}

TEST(X509Test, TestFromBuffer) {
  size_t data_len;
  UniquePtr<uint8_t> data;
  ASSERT_TRUE(PEMToDER(&data, &data_len, kRootCAPEM));

  UniquePtr<CRYPTO_BUFFER> buf(
      CRYPTO_BUFFER_new(data.get(), data_len, nullptr));
  ASSERT_TRUE(buf);
  UniquePtr<X509> root(X509_parse_from_buffer(buf.get()));
  ASSERT_TRUE(root);

  EXPECT_EQ(buf.get(), FromOpaque(root.get())->buf.get());
  buf.reset();

  // This ensures the X509 took a reference to `buf`, otherwise this will be a
  // reference to free memory and ASAN should notice.
  CRYPTO_BUFFER_len(FromOpaque(root.get())->buf.get());
}

TEST(X509Test, TestFromBufferWithTrailingData) {
  size_t data_len;
  UniquePtr<uint8_t> data;
  ASSERT_TRUE(PEMToDER(&data, &data_len, kRootCAPEM));

  auto trailing_data = std::make_unique<uint8_t[]>(data_len + 1);
  OPENSSL_memcpy(trailing_data.get(), data.get(), data_len);

  UniquePtr<CRYPTO_BUFFER> buf_trailing_data(
      CRYPTO_BUFFER_new(trailing_data.get(), data_len + 1, nullptr));
  ASSERT_TRUE(buf_trailing_data);

  UniquePtr<X509> root_trailing_data(
      X509_parse_from_buffer(buf_trailing_data.get()));
  ASSERT_FALSE(root_trailing_data);
}

TEST(X509Test, TestFromBufferModified) {
  size_t data_len;
  UniquePtr<uint8_t> data;
  ASSERT_TRUE(PEMToDER(&data, &data_len, kRootCAPEM));

  UniquePtr<CRYPTO_BUFFER> buf(
      CRYPTO_BUFFER_new(data.get(), data_len, nullptr));
  ASSERT_TRUE(buf);

  UniquePtr<X509> root(X509_parse_from_buffer(buf.get()));
  ASSERT_TRUE(root);

  UniquePtr<ASN1_INTEGER> forty_two(ASN1_INTEGER_new());
  ASN1_INTEGER_set_int64(forty_two.get(), 42);
  X509_set_serialNumber(root.get(), forty_two.get());

  ASSERT_EQ(static_cast<long>(data_len), i2d_X509(root.get(), nullptr));

  // Re-encode the TBSCertificate.
  i2d_re_X509_tbs(root.get(), nullptr);

  ASSERT_NE(static_cast<long>(data_len), i2d_X509(root.get(), nullptr));
}

TEST(X509Test, TestFromBufferReused) {
  size_t data_len;
  UniquePtr<uint8_t> data;
  ASSERT_TRUE(PEMToDER(&data, &data_len, kRootCAPEM));

  UniquePtr<CRYPTO_BUFFER> buf(
      CRYPTO_BUFFER_new(data.get(), data_len, nullptr));
  ASSERT_TRUE(buf);

  UniquePtr<X509> root(X509_parse_from_buffer(buf.get()));
  ASSERT_TRUE(root);

  size_t data2_len;
  UniquePtr<uint8_t> data2;
  ASSERT_TRUE(PEMToDER(&data2, &data2_len, kLeafPEM));
  EXPECT_EQ(FromOpaque(root.get())->buf.get(), buf.get());

  // Historically, this function tested the interaction between
  // `X509_parse_from_buffer` and object reuse. We no longer support object
  // reuse, so `d2i_X509` will replace `raw` with a new object. However, we
  // retain this test to verify that releasing objects from `d2i_X509` works
  // correctly and doesn't keep the old buffer.
  X509 *raw = root.release();
  const uint8_t *inp = data2.get();
  X509 *ret = d2i_X509(&raw, &inp, data2_len);
  root.reset(raw);

  ASSERT_EQ(root.get(), ret);
  ASSERT_NE(buf.get(), FromOpaque(root.get())->buf.get());

  // Free `data2` and ensure that `root` took its own copy. Otherwise
  // serializing `root`, below, will trigger a use-after-free.
  data2.reset();

  uint8_t *i2d = nullptr;
  int i2d_len = i2d_X509(root.get(), &i2d);
  ASSERT_GE(i2d_len, 0);
  UniquePtr<uint8_t> i2d_storage(i2d);

  ASSERT_TRUE(PEMToDER(&data2, &data2_len, kLeafPEM));
  EXPECT_EQ(Bytes(i2d, i2d_len), Bytes(data2.get(), data2_len));
}

TEST(X509Test, TestFailedParseFromBuffer) {
  static const uint8_t kNonsense[] = {1, 2, 3, 4, 5};

  UniquePtr<CRYPTO_BUFFER> buf(
      CRYPTO_BUFFER_new(kNonsense, sizeof(kNonsense), nullptr));
  ASSERT_TRUE(buf);

  UniquePtr<X509> cert(X509_parse_from_buffer(buf.get()));
  ASSERT_FALSE(cert);
  ERR_clear_error();

  // Test a buffer with trailing data.
  size_t data_len;
  UniquePtr<uint8_t> data;
  ASSERT_TRUE(PEMToDER(&data, &data_len, kRootCAPEM));

  auto data_with_trailing_byte = std::make_unique<uint8_t[]>(data_len + 1);
  OPENSSL_memcpy(data_with_trailing_byte.get(), data.get(), data_len);
  data_with_trailing_byte[data_len] = 0;

  UniquePtr<CRYPTO_BUFFER> buf_with_trailing_byte(
      CRYPTO_BUFFER_new(data_with_trailing_byte.get(), data_len + 1, nullptr));
  ASSERT_TRUE(buf_with_trailing_byte);

  UniquePtr<X509> root(X509_parse_from_buffer(buf_with_trailing_byte.get()));
  ASSERT_FALSE(root);
  ERR_clear_error();
}

TEST(X509Test, TestPrintUTCTIME) {
  static const struct {
    const char *val, *want;
  } asn1_utctime_tests[] = {
      {"", "Bad time value"},

      // Correct RFC 5280 form. Test years < 2000 and > 2000.
      {"090303125425Z", "Mar  3 12:54:25 2009 GMT"},
      {"900303125425Z", "Mar  3 12:54:25 1990 GMT"},
      {"000303125425Z", "Mar  3 12:54:25 2000 GMT"},

      // Correct form, bad values.
      {"000000000000Z", "Bad time value"},
      {"999999999999Z", "Bad time value"},

      // Missing components.
      {"090303125425", "Bad time value"},
      {"9003031254", "Bad time value"},
      {"9003031254Z", "Bad time value"},

      // GENERALIZEDTIME confused for UTCTIME.
      {"20090303125425Z", "Bad time value"},

      // Legal ASN.1, but not legal RFC 5280.
      {"9003031254+0800", "Bad time value"},
      {"9003031254-0800", "Bad time value"},

      // Trailing garbage.
      {"9003031254Z ", "Bad time value"},
  };

  for (auto t : asn1_utctime_tests) {
    SCOPED_TRACE(t.val);
    UniquePtr<ASN1_UTCTIME> tm(ASN1_UTCTIME_new());
    ASSERT_TRUE(tm);
    UniquePtr<BIO> bio(BIO_new(BIO_s_mem()));
    ASSERT_TRUE(bio);

    // Use this instead of ASN1_UTCTIME_set() because some callers get
    // type-confused and pass ASN1_GENERALIZEDTIME to ASN1_UTCTIME_print().
    // ASN1_UTCTIME_set_string() is stricter, and would reject the inputs in
    // question.
    ASSERT_TRUE(ASN1_STRING_set(tm.get(), t.val, strlen(t.val)));
    const int ok = ASN1_UTCTIME_print(bio.get(), tm.get());

    const uint8_t *contents;
    size_t len;
    ASSERT_TRUE(BIO_mem_contents(bio.get(), &contents, &len));
    EXPECT_EQ(ok, (strcmp(t.want, "Bad time value") != 0) ? 1 : 0);
    EXPECT_EQ(t.want, BytesAsStringView(Span(contents, len)));
  }
}

TEST(X509Test, PrettyPrintIntegers) {
  static const char *kTests[] = {
      // Small numbers are pretty-printed in decimal.
      "0",
      "-1",
      "1",
      "42",
      "-42",
      "256",
      "-256",
      // Large numbers are pretty-printed in hex to avoid taking quadratic time.
      "0x0123456789",
      "-0x0123456789",
  };
  for (const char *in : kTests) {
    SCOPED_TRACE(in);
    BIGNUM *bn = nullptr;
    ASSERT_TRUE(BN_asc2bn(&bn, in));
    UniquePtr<BIGNUM> free_bn(bn);

    {
      UniquePtr<ASN1_INTEGER> asn1(BN_to_ASN1_INTEGER(bn, nullptr));
      ASSERT_TRUE(asn1);
      UniquePtr<char> out(i2s_ASN1_INTEGER(nullptr, asn1.get()));
      ASSERT_TRUE(out.get());
      EXPECT_STREQ(in, out.get());
    }

    {
      UniquePtr<ASN1_ENUMERATED> asn1(BN_to_ASN1_ENUMERATED(bn, nullptr));
      ASSERT_TRUE(asn1);
      UniquePtr<char> out(i2s_ASN1_ENUMERATED(nullptr, asn1.get()));
      ASSERT_TRUE(out.get());
      EXPECT_STREQ(in, out.get());
    }
  }
}

TEST(X509Test, X509AlgorSetMd) {
  UniquePtr<X509_ALGOR> alg(X509_ALGOR_new());
  ASSERT_TRUE(alg);
  EXPECT_TRUE(X509_ALGOR_set_md(alg.get(), EVP_sha256()));
  const ASN1_OBJECT *obj;
  const void *pval;
  int ptype = 0;
  X509_ALGOR_get0(&obj, &ptype, &pval, alg.get());
  EXPECT_TRUE(obj);
  EXPECT_EQ(OBJ_obj2nid(obj), NID_sha256);
  EXPECT_EQ(ptype, V_ASN1_NULL);  // OpenSSL has V_ASN1_UNDEF
  EXPECT_EQ(pval, nullptr);
  EXPECT_TRUE(X509_ALGOR_set_md(alg.get(), EVP_md5()));
  X509_ALGOR_get0(&obj, &ptype, &pval, alg.get());
  EXPECT_EQ(OBJ_obj2nid(obj), NID_md5);
  EXPECT_EQ(ptype, V_ASN1_NULL);
  EXPECT_EQ(pval, nullptr);
}

TEST(X509Test, X509NameSet) {
  UniquePtr<X509_NAME> name(X509_NAME_new());
  ASSERT_TRUE(name);
  EXPECT_TRUE(X509_NAME_add_entry_by_txt(
      name.get(), "C", MBSTRING_ASC, reinterpret_cast<const uint8_t *>("US"),
      -1, -1, 0));
  EXPECT_EQ(X509_NAME_entry_count(name.get()), 1);
  EXPECT_TRUE(X509_NAME_add_entry_by_txt(
      name.get(), "C", MBSTRING_ASC, reinterpret_cast<const uint8_t *>("CA"),
      -1, -1, 0));
  EXPECT_EQ(X509_NAME_entry_count(name.get()), 2);
  EXPECT_TRUE(X509_NAME_add_entry_by_txt(
      name.get(), "C", MBSTRING_ASC, reinterpret_cast<const uint8_t *>("UK"),
      -1, -1, 0));
  EXPECT_EQ(X509_NAME_entry_count(name.get()), 3);
  EXPECT_TRUE(X509_NAME_add_entry_by_txt(
      name.get(), "C", MBSTRING_ASC, reinterpret_cast<const uint8_t *>("JP"),
      -1, 1, 0));
  EXPECT_EQ(X509_NAME_entry_count(name.get()), 4);

  // Check that the correct entries get incremented when inserting new entry.
  EXPECT_EQ(X509_NAME_ENTRY_set(X509_NAME_get_entry(name.get(), 1)), 1);
  EXPECT_EQ(X509_NAME_ENTRY_set(X509_NAME_get_entry(name.get(), 2)), 2);
}

// Tests that `X509_NAME_hash` and `X509_NAME_hash_old`'s values never change.
// These functions figure into `X509_LOOKUP_hash_dir`'s on-disk format, so they
// must remain stable. In particular, if we ever remove name canonicalization,
// we'll need to preserve it for `X509_NAME_hash`.
TEST(X509Test, NameHash) {
  struct {
    std::vector<uint8_t> name_der;
    uint32_t hash;
    uint32_t hash_old;
  } kTests[] = {
      // SEQUENCE {
      //   SET {
      //     SEQUENCE {
      //       # commonName
      //       OBJECT_IDENTIFIER { 2.5.4.3 }
      //       UTF8String { "Test Name" }
      //     }
      //   }
      // }
      {{0x30, 0x14, 0x31, 0x12, 0x30, 0x10, 0x06, 0x03, 0x55, 0x04, 0x03,
        0x0c, 0x09, 0x54, 0x65, 0x73, 0x74, 0x20, 0x4e, 0x61, 0x6d, 0x65},
       0xc90fba01,
       0x8c0d4fea},

      // This name canonicalizes to the same value, with OpenSSL's algorithm, as
      // the above input, so `hash` matches. `hash_old` doesn't use
      // canonicalization and does not match.
      //
      // SEQUENCE {
      //   SET {
      //     SEQUENCE {
      //       # commonName
      //       OBJECT_IDENTIFIER { 2.5.4.3 }
      //       BMPString {
      //         u"\x09\n\x0b\x0c\x0d tEST\x09\n\x0b\x0c\x0d "
      //         u"\x09\n\x0b\x0c\x0d nAME\x09\n\x0b\x0c\x0d "
      //       }
      //     }
      //   }
      // }
      {{0x30, 0x4b, 0x31, 0x49, 0x30, 0x47, 0x06, 0x03, 0x55, 0x04, 0x03,
        0x1e, 0x40, 0x00, 0x09, 0x00, 0x0a, 0x00, 0x0b, 0x00, 0x0c, 0x00,
        0x0d, 0x00, 0x20, 0x00, 0x74, 0x00, 0x45, 0x00, 0x53, 0x00, 0x54,
        0x00, 0x09, 0x00, 0x0a, 0x00, 0x0b, 0x00, 0x0c, 0x00, 0x0d, 0x00,
        0x20, 0x00, 0x09, 0x00, 0x0a, 0x00, 0x0b, 0x00, 0x0c, 0x00, 0x0d,
        0x00, 0x20, 0x00, 0x6e, 0x00, 0x41, 0x00, 0x4d, 0x00, 0x45, 0x00,
        0x09, 0x00, 0x0a, 0x00, 0x0b, 0x00, 0x0c, 0x00, 0x0d, 0x00, 0x20},
       0xc90fba01,
       0xbe2dd8c8},

      // OCTET STRING should never be canonicalized. It does not have a defined
      // encoding.
      //
      // SEQUENCE {
      //   SET {
      //     SEQUENCE {
      //       # commonName
      //       OBJECT_IDENTIFIER { 2.5.4.3 }
      //       OCTET_STRING { "Test Name" }
      //     }
      //   }
      // }
      {{0x30, 0x14, 0x31, 0x12, 0x30, 0x10, 0x06, 0x03, 0x55, 0x04, 0x03,
        0x04, 0x09, 0x54, 0x65, 0x73, 0x74, 0x20, 0x4e, 0x61, 0x6d, 0x65},
       0x4985589c,
       0x457dbefa},

      // The set of string types that we are canonicalized in `hash` cannot
      // increase. (We also would not want to increase it anyway. Name
      // canonicalization was a mistake.)
      //
      // SEQUENCE {
      //   SET {
      //     SEQUENCE {
      //       # commonName
      //       OBJECT_IDENTIFIER { 2.5.4.3 }
      //       GeneralString { "Test Name" }
      //     }
      //   }
      // }
      {{0x30, 0x14, 0x31, 0x12, 0x30, 0x10, 0x06, 0x03, 0x55, 0x04, 0x03,
        0x1b, 0x09, 0x54, 0x65, 0x73, 0x74, 0x20, 0x4e, 0x61, 0x6d, 0x65},
       0xe6b4efbf,
       0x186fd8dc},
  };
  for (const auto &t : kTests) {
    SCOPED_TRACE(Bytes(t.name_der));
    const uint8_t *der = t.name_der.data();
    UniquePtr<X509_NAME> name(d2i_X509_NAME(nullptr, &der, t.name_der.size()));
    ASSERT_TRUE(name);
    EXPECT_EQ(t.hash, X509_NAME_hash(name.get()));
    EXPECT_EQ(t.hash_old, X509_NAME_hash_old(name.get()));
  }
}

TEST(X509Test, NoBasicConstraintsCertSign) {
  UniquePtr<X509> root(CertFromPEM(kSANTypesRoot));
  UniquePtr<X509> intermediate(
      CertFromPEM(kNoBasicConstraintsCertSignIntermediate));
  UniquePtr<X509> leaf(CertFromPEM(kNoBasicConstraintsCertSignLeaf));

  ASSERT_TRUE(root);
  ASSERT_TRUE(intermediate);
  ASSERT_TRUE(leaf);

  // The intermediate has keyUsage certSign, but is not marked as a CA in the
  // basicConstraints.
  EXPECT_EQ(X509_V_ERR_INVALID_CA,
            Verify(leaf.get(), {root.get()}, {intermediate.get()}, {}, 0));

  // `X509_check_purpose` with `X509_PURPOSE_ANY` and purpose -1 do not check
  // basicConstraints, but other purpose types do. (This is redundant with the
  // actual basicConstraints check, but `X509_check_purpose` is public API.)
  EXPECT_TRUE(X509_check_purpose(intermediate.get(), -1, /*ca=*/1));
  EXPECT_TRUE(
      X509_check_purpose(intermediate.get(), X509_PURPOSE_ANY, /*ca=*/1));
  EXPECT_FALSE(X509_check_purpose(intermediate.get(), X509_PURPOSE_SSL_SERVER,
                                  /*ca=*/1));
}

TEST(X509Test, NoBasicConstraintsNetscapeCA) {
  UniquePtr<X509> root(CertFromPEM(kSANTypesRoot));
  UniquePtr<X509> intermediate(
      CertFromPEM(kNoBasicConstraintsNetscapeCAIntermediate));
  UniquePtr<X509> leaf(CertFromPEM(kNoBasicConstraintsNetscapeCALeaf));

  ASSERT_TRUE(root);
  ASSERT_TRUE(intermediate);
  ASSERT_TRUE(leaf);

  // The intermediate has a Netscape certificate type of "SSL CA", but is not
  // marked as a CA in the basicConstraints.
  EXPECT_EQ(X509_V_ERR_INVALID_CA,
            Verify(leaf.get(), {root.get()}, {intermediate.get()}, {}, 0));
}

TEST(X509Test, MismatchAlgorithms) {
  UniquePtr<X509> cert(CertFromPEM(kSelfSignedMismatchAlgorithms));
  ASSERT_TRUE(cert);

  UniquePtr<EVP_PKEY> pkey(X509_get_pubkey(cert.get()));
  ASSERT_TRUE(pkey);

  EXPECT_FALSE(X509_verify(cert.get(), pkey.get()));
  EXPECT_TRUE(ErrorEquals(ERR_get_error(), ERR_LIB_X509,
                          X509_R_SIGNATURE_ALGORITHM_MISMATCH));
}

// TODO(crbug.com/387737061): Test that this function can decrypt certificates
// and CRLs, even though it leaves encrypted private keys alone.
TEST(X509Test, PEMX509Info) {
  std::string cert = kRootCAPEM;
  auto cert_obj = CertFromPEM(kRootCAPEM);
  ASSERT_TRUE(cert_obj);

  std::string rsa = kRSAKey;
  auto rsa_obj = PrivateKeyFromPEM(kRSAKey);
  ASSERT_TRUE(rsa_obj);

  std::string crl = kBasicCRL;
  auto crl_obj = CRLFromPEM(kBasicCRL);
  ASSERT_TRUE(crl_obj);

  UniquePtr<EVP_PKEY> placeholder_key(EVP_PKEY_new());
  ASSERT_TRUE(placeholder_key);

  std::string unknown =
      "-----BEGIN UNKNOWN-----\n"
      "AAAA\n"
      "-----END UNKNOWN-----\n";

  std::string invalid =
      "-----BEGIN CERTIFICATE-----\n"
      "AAAA\n"
      "-----END CERTIFICATE-----\n";

  std::string encrypted_key = R"(-----BEGIN EC PRIVATE KEY-----
Proc-Type: 4,ENCRYPTED
DEK-Info: AES-128-CBC,B3B2988AECAE6EAB0D043105994C1123

RK7DUIGDHWTFh2rpTX+dR88hUyC1PyDlIULiNCkuWFwHrJbc1gM6hMVOKmU196XC
iITrIKmilFm9CPD6Tpfk/NhI/QPxyJlk1geIkxpvUZ2FCeMuYI1To14oYOUKv14q
wr6JtaX2G+pOmwcSPymZC4u2TncAP7KHgS8UGcMw8CE=
-----END EC PRIVATE KEY-----
)";

  // Each X509_INFO contains at most one certificate, CRL, etc. The format
  // creates a new X509_INFO when a repeated type is seen.
  std::string pem =
      // The first few entries have one of everything in different orders.
      cert + rsa + crl + rsa + crl + cert +
      // Unknown types are ignored.
      crl + unknown + cert + rsa +
      // Seeing a new certificate starts a new entry, so now we have a bunch of
      // certificate-only entries.
      cert + cert + cert +
      // The key folds into the certificate's entry.
      cert + rsa +
      // Doubled keys also start new entries.
      rsa + rsa + rsa + rsa + crl +
      // As do CRLs.
      crl + crl +
      // Encrypted private keys are not decrypted (decryption failures would be
      // fatal) and just returned as placeholder.
      crl + cert + encrypted_key +
      // Placeholder keys are still keys, so a new key starts a new entry.
      rsa;

  const struct ExpectedInfo {
    const X509 *cert;
    const EVP_PKEY *key;
    const X509_CRL *crl;
  } kExpected[] = {
      {cert_obj.get(), rsa_obj.get(), crl_obj.get()},
      {cert_obj.get(), rsa_obj.get(), crl_obj.get()},
      {cert_obj.get(), rsa_obj.get(), crl_obj.get()},
      {cert_obj.get(), nullptr, nullptr},
      {cert_obj.get(), nullptr, nullptr},
      {cert_obj.get(), nullptr, nullptr},
      {cert_obj.get(), rsa_obj.get(), nullptr},
      {nullptr, rsa_obj.get(), nullptr},
      {nullptr, rsa_obj.get(), nullptr},
      {nullptr, rsa_obj.get(), nullptr},
      {nullptr, rsa_obj.get(), crl_obj.get()},
      {nullptr, nullptr, crl_obj.get()},
      {nullptr, nullptr, crl_obj.get()},
      {cert_obj.get(), placeholder_key.get(), crl_obj.get()},
      {nullptr, rsa_obj.get(), nullptr},
  };

  auto check_info = [](const ExpectedInfo *expected, const X509_INFO *info) {
    if (expected->cert != nullptr) {
      EXPECT_EQ(0, X509_cmp(expected->cert, info->x509));
    } else {
      EXPECT_EQ(nullptr, info->x509);
    }
    if (expected->crl != nullptr) {
      EXPECT_EQ(0, X509_CRL_cmp(expected->crl, info->crl));
    } else {
      EXPECT_EQ(nullptr, info->crl);
    }
    if (expected->key != nullptr) {
      ASSERT_NE(nullptr, info->x_pkey);
      if (EVP_PKEY_id(expected->key) == EVP_PKEY_NONE) {
        // Expect a placeholder key.
        EXPECT_FALSE(info->x_pkey->dec_pkey);
      } else {
        ASSERT_TRUE(info->x_pkey->dec_pkey);
        EXPECT_EQ(1, EVP_PKEY_eq(expected->key, info->x_pkey->dec_pkey));
      }
    } else {
      EXPECT_EQ(nullptr, info->x_pkey);
    }
  };

  UniquePtr<BIO> bio(BIO_new_mem_buf(pem.data(), pem.size()));
  ASSERT_TRUE(bio);
  UniquePtr<STACK_OF(X509_INFO)> infos(
      PEM_X509_INFO_read_bio(bio.get(), nullptr, nullptr, nullptr));
  ASSERT_TRUE(infos);
  ASSERT_EQ(std::size(kExpected), sk_X509_INFO_num(infos.get()));
  for (size_t i = 0; i < std::size(kExpected); i++) {
    SCOPED_TRACE(i);
    check_info(&kExpected[i], sk_X509_INFO_value(infos.get(), i));
  }

  // Passing an existing stack appends to it.
  bio.reset(BIO_new_mem_buf(pem.data(), pem.size()));
  ASSERT_TRUE(bio);
  ASSERT_EQ(infos.get(),
            PEM_X509_INFO_read_bio(bio.get(), infos.get(), nullptr, nullptr));
  ASSERT_EQ(2 * std::size(kExpected), sk_X509_INFO_num(infos.get()));
  for (size_t i = 0; i < std::size(kExpected); i++) {
    SCOPED_TRACE(i);
    check_info(&kExpected[i], sk_X509_INFO_value(infos.get(), i));
    check_info(&kExpected[i],
               sk_X509_INFO_value(infos.get(), i + std::size(kExpected)));
  }

  // Gracefully handle errors in both the append and fresh cases.
  std::string bad_pem = cert + cert + invalid;

  bio.reset(BIO_new_mem_buf(bad_pem.data(), bad_pem.size()));
  ASSERT_TRUE(bio);
  UniquePtr<STACK_OF(X509_INFO)> infos2(
      PEM_X509_INFO_read_bio(bio.get(), nullptr, nullptr, nullptr));
  EXPECT_FALSE(infos2);
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_ASN1, ASN1_R_DECODE_ERROR}}));

  bio.reset(BIO_new_mem_buf(bad_pem.data(), bad_pem.size()));
  ASSERT_TRUE(bio);
  EXPECT_FALSE(
      PEM_X509_INFO_read_bio(bio.get(), infos.get(), nullptr, nullptr));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_ASN1, ASN1_R_DECODE_ERROR}}));
  EXPECT_EQ(2 * std::size(kExpected), sk_X509_INFO_num(infos.get()));
}

TEST(X509Test, ReadBIOEmpty) {
  UniquePtr<BIO> bio(BIO_new_mem_buf(nullptr, 0));
  ASSERT_TRUE(bio);

  // CPython expects `ASN1_R_HEADER_TOO_LONG` on EOF, to terminate a series of
  // certificates.
  UniquePtr<X509> x509(d2i_X509_bio(bio.get(), nullptr));
  EXPECT_FALSE(x509);
  EXPECT_TRUE(
      ErrorEquals(ERR_get_error(), ERR_LIB_ASN1, ASN1_R_HEADER_TOO_LONG));
}

TEST(X509Test, ReadBIOOneByte) {
  UniquePtr<BIO> bio(BIO_new_mem_buf("\x30", 1));
  ASSERT_TRUE(bio);

  // CPython expects `ASN1_R_HEADER_TOO_LONG` on EOF, to terminate a series of
  // certificates. This EOF appeared after some data, however, so we do not wish
  // to signal EOF.
  UniquePtr<X509> x509(d2i_X509_bio(bio.get(), nullptr));
  EXPECT_FALSE(x509);
  EXPECT_TRUE(
      ErrorEquals(ERR_get_error(), ERR_LIB_ASN1, ASN1_R_NOT_ENOUGH_DATA));
}

TEST(X509Test, PartialBIOReturn) {
  // Create a filter BIO that only reads and writes one byte at a time.
  UniquePtr<BIO_METHOD> method(BIO_meth_new(0, nullptr));
  ASSERT_TRUE(method);
  ASSERT_TRUE(BIO_meth_set_create(method.get(), [](BIO *b) -> int {
    BIO_set_init(b, 1);
    return 1;
  }));
  ASSERT_TRUE(
      BIO_meth_set_read(method.get(), [](BIO *b, char *out, int len) -> int {
        return BIO_read(BIO_next(b), out, std::min(len, 1));
      }));
  ASSERT_TRUE(BIO_meth_set_write(
      method.get(), [](BIO *b, const char *in, int len) -> int {
        return BIO_write(BIO_next(b), in, std::min(len, 1));
      }));

  UniquePtr<BIO> bio(BIO_new(method.get()));
  ASSERT_TRUE(bio);
  BIO *mem_bio = BIO_new(BIO_s_mem());
  ASSERT_TRUE(mem_bio);
  BIO_push(bio.get(), mem_bio);  // BIO_push takes ownership.

  UniquePtr<X509> cert(CertFromPEM(kLeafPEM));
  ASSERT_TRUE(cert);
  uint8_t *der = nullptr;
  int der_len = i2d_X509(cert.get(), &der);
  ASSERT_GT(der_len, 0);
  UniquePtr<uint8_t> free_der(der);

  // Write the certificate into the BIO. Though we only write one byte at a
  // time, the write should succeed.
  ASSERT_EQ(1, i2d_X509_bio(bio.get(), cert.get()));
  const uint8_t *der2;
  size_t der2_len;
  ASSERT_TRUE(BIO_mem_contents(mem_bio, &der2, &der2_len));
  EXPECT_EQ(Bytes(der, static_cast<size_t>(der_len)), Bytes(der2, der2_len));

  // Read the certificate back out of the BIO. Though we only read one byte at a
  // time, the read should succeed.
  UniquePtr<X509> cert2(d2i_X509_bio(bio.get(), nullptr));
  ASSERT_TRUE(cert2);
  EXPECT_EQ(0, X509_cmp(cert.get(), cert2.get()));
}

TEST(X509Test, CommonNameFallback) {
  UniquePtr<X509> root = CertFromPEM(kSANTypesRoot);
  ASSERT_TRUE(root);
  UniquePtr<X509> with_sans = CertFromPEM(kCommonNameWithSANs);
  ASSERT_TRUE(with_sans);
  UniquePtr<X509> without_sans = CertFromPEM(kCommonNameWithoutSANs);
  ASSERT_TRUE(without_sans);
  UniquePtr<X509> with_email = CertFromPEM(kCommonNameWithEmailSAN);
  ASSERT_TRUE(with_email);
  UniquePtr<X509> with_ip = CertFromPEM(kCommonNameWithIPSAN);
  ASSERT_TRUE(with_ip);

  auto verify_cert = [&](X509 *leaf, unsigned flags, const char *host) {
    return Verify(leaf, {root.get()}, {}, {}, 0, [&](X509_STORE_CTX *ctx) {
      X509_VERIFY_PARAM *param = X509_STORE_CTX_get0_param(ctx);
      ASSERT_TRUE(X509_VERIFY_PARAM_set1_host(param, host, strlen(host)));
      X509_VERIFY_PARAM_set_hostflags(param, flags);
    });
  };

  // By default, the common name is ignored if the SAN list is present but
  // otherwise is checked.
  EXPECT_EQ(X509_V_ERR_HOSTNAME_MISMATCH,
            verify_cert(with_sans.get(), 0 /* no flags */, "foo.host1.test"));
  EXPECT_EQ(X509_V_OK,
            verify_cert(with_sans.get(), 0 /* no flags */, "foo.host2.test"));
  EXPECT_EQ(X509_V_OK,
            verify_cert(with_sans.get(), 0 /* no flags */, "foo.host3.test"));
  EXPECT_EQ(X509_V_OK, verify_cert(without_sans.get(), 0 /* no flags */,
                                   "foo.host1.test"));
  EXPECT_EQ(X509_V_ERR_HOSTNAME_MISMATCH,
            verify_cert(with_email.get(), 0 /* no flags */, "foo.host1.test"));
  EXPECT_EQ(X509_V_ERR_HOSTNAME_MISMATCH,
            verify_cert(with_ip.get(), 0 /* no flags */, "foo.host1.test"));

  // X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT is ignored.
  EXPECT_EQ(X509_V_ERR_HOSTNAME_MISMATCH,
            verify_cert(with_sans.get(), X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT,
                        "foo.host1.test"));
  EXPECT_EQ(X509_V_OK,
            verify_cert(with_sans.get(), X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT,
                        "foo.host2.test"));
  EXPECT_EQ(X509_V_OK,
            verify_cert(with_sans.get(), X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT,
                        "foo.host3.test"));
  EXPECT_EQ(X509_V_OK, verify_cert(without_sans.get(),
                                   X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT,
                                   "foo.host1.test"));
  EXPECT_EQ(X509_V_ERR_HOSTNAME_MISMATCH,
            verify_cert(with_email.get(), X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT,
                        "foo.host1.test"));
  EXPECT_EQ(X509_V_ERR_HOSTNAME_MISMATCH,
            verify_cert(with_ip.get(), X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT,
                        "foo.host1.test"));

  // X509_CHECK_FLAG_NEVER_CHECK_SUBJECT implements the correct behavior: the
  // common name is never checked.
  EXPECT_EQ(X509_V_ERR_HOSTNAME_MISMATCH,
            verify_cert(with_sans.get(), X509_CHECK_FLAG_NEVER_CHECK_SUBJECT,
                        "foo.host1.test"));
  EXPECT_EQ(X509_V_OK,
            verify_cert(with_sans.get(), X509_CHECK_FLAG_NEVER_CHECK_SUBJECT,
                        "foo.host2.test"));
  EXPECT_EQ(X509_V_OK,
            verify_cert(with_sans.get(), X509_CHECK_FLAG_NEVER_CHECK_SUBJECT,
                        "foo.host3.test"));
  EXPECT_EQ(X509_V_ERR_HOSTNAME_MISMATCH,
            verify_cert(without_sans.get(), X509_CHECK_FLAG_NEVER_CHECK_SUBJECT,
                        "foo.host1.test"));
  EXPECT_EQ(X509_V_ERR_HOSTNAME_MISMATCH,
            verify_cert(with_email.get(), X509_CHECK_FLAG_NEVER_CHECK_SUBJECT,
                        "foo.host1.test"));
  EXPECT_EQ(X509_V_ERR_HOSTNAME_MISMATCH,
            verify_cert(with_ip.get(), X509_CHECK_FLAG_NEVER_CHECK_SUBJECT,
                        "foo.host1.test"));
}

// Test that it is possible to set host flags on the store and hosts on the
// individual verify operation.
TEST(X509Test, SeparateHostFlagsAndHosts) {
  UniquePtr<X509> root = CertFromPEM(kSANTypesRoot);
  ASSERT_TRUE(root);
  UniquePtr<X509> without_sans = CertFromPEM(kCommonNameWithoutSANs);
  ASSERT_TRUE(without_sans);
  std::string_view host = "foo.host1.test";

  UniquePtr<X509_STORE> store(X509_STORE_new());
  ASSERT_TRUE(store);
  ASSERT_TRUE(X509_STORE_add_cert(store.get(), root.get()));

  // By default, we allow the common name fallback. This is just to establish a
  // baseline. If this fails (e.g. if we turn off the common name fallback by
  // default), this test will need to be updated with a different flag.
  {
    UniquePtr<X509_STORE_CTX> ctx(X509_STORE_CTX_new());
    ASSERT_TRUE(ctx);
    ASSERT_TRUE(X509_STORE_CTX_init(ctx.get(), store.get(), without_sans.get(),
                                    nullptr));
    ASSERT_TRUE(X509_VERIFY_PARAM_set1_host(
        X509_STORE_CTX_get0_param(ctx.get()), host.data(), host.size()));
    X509_STORE_CTX_set_time_posix(ctx.get(), /*flags=*/0, kReferenceTime);
    EXPECT_EQ(1, X509_verify_cert(ctx.get()));
    EXPECT_EQ(X509_V_OK, X509_STORE_CTX_get_error(ctx.get()));
  }

  // Disabling the common name fallback on the store should work.
  X509_VERIFY_PARAM_set_hostflags(X509_STORE_get0_param(store.get()),
                                  X509_CHECK_FLAG_NEVER_CHECK_SUBJECT);
  {
    UniquePtr<X509_STORE_CTX> ctx(X509_STORE_CTX_new());
    ASSERT_TRUE(ctx);
    ASSERT_TRUE(X509_STORE_CTX_init(ctx.get(), store.get(), without_sans.get(),
                                    nullptr));
    ASSERT_TRUE(X509_VERIFY_PARAM_set1_host(
        X509_STORE_CTX_get0_param(ctx.get()), host.data(), host.size()));
    X509_STORE_CTX_set_time_posix(ctx.get(), /*flags=*/0, kReferenceTime);
    EXPECT_EQ(0, X509_verify_cert(ctx.get()));
    EXPECT_EQ(X509_V_ERR_HOSTNAME_MISMATCH,
              X509_STORE_CTX_get_error(ctx.get()));
  }
}

TEST(X509Test, LooksLikeDNSName) {
  static const char *kValid[] = {
      "example.com",  "eXample123-.com", "*.example.com",
      "exa_mple.com", "example.com.",    "project-dev:us-central1:main",
  };
  static const char *kInvalid[] = {
      "-eXample123-.com",
      "",
      ".",
      "*",
      "*.",
      "example..com",
      ".example.com",
      "example.com..",
      "*foo.example.com",
      "foo.*.example.com",
      "foo,bar",
  };

  for (const char *str : kValid) {
    SCOPED_TRACE(str);
    EXPECT_TRUE(x509v3_looks_like_dns_name(
        reinterpret_cast<const uint8_t *>(str), strlen(str)));
  }
  for (const char *str : kInvalid) {
    SCOPED_TRACE(str);
    EXPECT_FALSE(x509v3_looks_like_dns_name(
        reinterpret_cast<const uint8_t *>(str), strlen(str)));
  }
}

TEST(X509Test, CommonNameAndNameConstraints) {
  UniquePtr<X509> root = CertFromPEM(kSANTypesRoot);
  ASSERT_TRUE(root);
  UniquePtr<X509> intermediate = CertFromPEM(kConstrainedIntermediate);
  ASSERT_TRUE(intermediate);
  UniquePtr<X509> permitted = CertFromPEM(kCommonNamePermittedLeaf);
  ASSERT_TRUE(permitted);
  UniquePtr<X509> not_permitted = CertFromPEM(kCommonNameNotPermittedLeaf);
  ASSERT_TRUE(not_permitted);
  UniquePtr<X509> not_permitted_with_sans =
      CertFromPEM(kCommonNameNotPermittedWithSANsLeaf);
  ASSERT_TRUE(not_permitted_with_sans);
  UniquePtr<X509> not_dns = CertFromPEM(kCommonNameNotDNSLeaf);
  ASSERT_TRUE(not_dns);

  auto verify_cert = [&](X509 *leaf, unsigned flags, const char *host) {
    return Verify(
        leaf, {root.get()}, {intermediate.get()}, {}, 0,
        [&](X509_STORE_CTX *ctx) {
          X509_VERIFY_PARAM *param = X509_STORE_CTX_get0_param(ctx);
          ASSERT_TRUE(X509_VERIFY_PARAM_set1_host(param, host, strlen(host)));
          X509_VERIFY_PARAM_set_hostflags(param, flags);
        });
  };

  // Certificates which would otherwise trigger the common name fallback are
  // rejected whenever there are name constraints. We do this whether or not
  // the common name matches the constraints.
  EXPECT_EQ(
      X509_V_ERR_NAME_CONSTRAINTS_WITHOUT_SANS,
      verify_cert(permitted.get(), 0 /* no flags */, kCommonNamePermitted));
  EXPECT_EQ(X509_V_ERR_NAME_CONSTRAINTS_WITHOUT_SANS,
            verify_cert(not_permitted.get(), 0 /* no flags */,
                        kCommonNameNotPermitted));

  // This occurs even if the built-in name checks aren't used. The caller may
  // separately call `X509_check_host`.
  EXPECT_EQ(X509_V_ERR_NAME_CONSTRAINTS_WITHOUT_SANS,
            Verify(not_permitted.get(), {root.get()}, {intermediate.get()}, {},
                   0 /* no flags */, nullptr));

  // If the leaf certificate has SANs, the common name fallback is always
  // disabled, so the name constraints do not apply.
  EXPECT_EQ(X509_V_OK, Verify(not_permitted_with_sans.get(), {root.get()},
                              {intermediate.get()}, {}, 0, nullptr));
  EXPECT_EQ(X509_V_ERR_HOSTNAME_MISMATCH,
            verify_cert(not_permitted_with_sans.get(), 0 /* no flags */,
                        kCommonNameNotPermittedWithSANs));

  // If the common name does not look like a DNS name, we apply neither name
  // constraints nor common name fallback.
  EXPECT_EQ(X509_V_OK, Verify(not_dns.get(), {root.get()}, {intermediate.get()},
                              {}, 0, nullptr));
  EXPECT_EQ(X509_V_ERR_HOSTNAME_MISMATCH,
            verify_cert(not_dns.get(), 0 /* no flags */, kCommonNameNotDNS));
}

TEST(X509Test, ServerGatedCryptoEKUs) {
  UniquePtr<X509> root = CertFromPEM(kSANTypesRoot);
  ASSERT_TRUE(root);
  UniquePtr<X509> ms_sgc = CertFromPEM(kMicrosoftSGCCert);
  ASSERT_TRUE(ms_sgc);
  UniquePtr<X509> ns_sgc = CertFromPEM(kNetscapeSGCCert);
  ASSERT_TRUE(ns_sgc);
  UniquePtr<X509> server_eku = CertFromPEM(kServerEKUCert);
  ASSERT_TRUE(server_eku);
  UniquePtr<X509> server_eku_plus_ms_sgc =
      CertFromPEM(kServerEKUPlusMicrosoftSGCCert);
  ASSERT_TRUE(server_eku_plus_ms_sgc);
  UniquePtr<X509> any_eku = CertFromPEM(kAnyEKU);
  ASSERT_TRUE(any_eku);
  UniquePtr<X509> no_eku = CertFromPEM(kNoEKU);
  ASSERT_TRUE(no_eku);

  auto verify_cert = [&root](X509 *leaf) {
    return Verify(leaf, {root.get()}, /*intermediates=*/{}, /*crls=*/{},
                  /*flags=*/0, [&](X509_STORE_CTX *ctx) {
                    X509_VERIFY_PARAM *param = X509_STORE_CTX_get0_param(ctx);
                    ASSERT_TRUE(X509_VERIFY_PARAM_set_purpose(
                        param, X509_PURPOSE_SSL_SERVER));
                  });
  };

  // Neither the Microsoft nor Netscape SGC EKU should be sufficient for
  // `X509_PURPOSE_SSL_SERVER`. The "any" EKU probably, technically, should be.
  // However, we've never accepted it and it's not acceptable in leaf
  // certificates by the Baseline, so perhaps we don't need this complexity.
  for (X509 *leaf : {ms_sgc.get(), ns_sgc.get(), any_eku.get()}) {
    EXPECT_EQ(X509_V_ERR_INVALID_PURPOSE, verify_cert(leaf));
  }

  // The server-auth EKU is sufficient, and it doesn't matter if an SGC EKU is
  // also included. Lastly, not specifying an EKU is also valid.
  for (X509 *leaf :
       {server_eku.get(), server_eku_plus_ms_sgc.get(), no_eku.get()}) {
    EXPECT_EQ(X509_V_OK, verify_cert(leaf));
  }
}

// Test that invalid extensions are rejected by, if not the parser, at least the
// verifier.
TEST(X509Test, InvalidExtensions) {
  UniquePtr<X509> root =
      CertFromPEM(GetTestData("crypto/x509/test/invalid_extension_root.pem"));
  ASSERT_TRUE(root);
  UniquePtr<X509> intermediate = CertFromPEM(
      GetTestData("crypto/x509/test/invalid_extension_intermediate.pem"));
  ASSERT_TRUE(intermediate);
  UniquePtr<X509> leaf =
      CertFromPEM(GetTestData("crypto/x509/test/invalid_extension_leaf.pem"));
  ASSERT_TRUE(leaf);

  // Sanity-check that the baseline chain is accepted.
  EXPECT_EQ(X509_V_OK,
            Verify(leaf.get(), {root.get()}, {intermediate.get()}, {}));

  static const char *kExtensions[] = {
      "authority_key_identifier",
      "basic_constraints",
      "ext_key_usage",
      "key_usage",
      "name_constraints",
      "subject_alt_name",
      "subject_key_identifier",
  };
  for (const char *ext : kExtensions) {
    SCOPED_TRACE(ext);
    UniquePtr<X509> invalid_root = CertFromPEM(GetTestData(
        (std::string("crypto/x509/test/invalid_extension_root_") + ext + ".pem")
            .c_str()));
    ASSERT_TRUE(invalid_root);

    UniquePtr<X509> invalid_intermediate = CertFromPEM(GetTestData(
        (std::string("crypto/x509/test/invalid_extension_intermediate_") + ext +
         ".pem")
            .c_str()));
    ASSERT_TRUE(invalid_intermediate);

    UniquePtr<X509> invalid_leaf = CertFromPEM(GetTestData(
        (std::string("crypto/x509/test/invalid_extension_leaf_") + ext + ".pem")
            .c_str()));
    ASSERT_TRUE(invalid_leaf);

    UniquePtr<X509> trailing_leaf = CertFromPEM(GetTestData(
        (std::string("crypto/x509/test/trailing_data_leaf_") + ext + ".pem")
            .c_str()));
    ASSERT_TRUE(trailing_leaf);

    EXPECT_EQ(
        X509_V_ERR_INVALID_EXTENSION,
        Verify(invalid_leaf.get(), {root.get()}, {intermediate.get()}, {}));

    EXPECT_EQ(
        X509_V_ERR_INVALID_EXTENSION,
        Verify(trailing_leaf.get(), {root.get()}, {intermediate.get()}, {}));

    // If the invalid extension is on an intermediate or root,
    // `X509_verify_cert` notices by way of being unable to build a path to
    // a valid issuer.
    EXPECT_EQ(
        X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY,
        Verify(leaf.get(), {root.get()}, {invalid_intermediate.get()}, {}));
    EXPECT_EQ(
        X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY,
        Verify(leaf.get(), {invalid_root.get()}, {intermediate.get()}, {}));
  }
}

// kExplicitDefaultVersionPEM is an X.509v1 certificate with the version number
// encoded explicitly, rather than omitted as required by DER.
static const char kExplicitDefaultVersionPEM[] = R"(
-----BEGIN CERTIFICATE-----
MIIBfTCCASSgAwIBAAIJANlMBNpJfb/rMAkGByqGSM49BAEwRTELMAkGA1UEBhMC
QVUxEzARBgNVBAgMClNvbWUtU3RhdGUxITAfBgNVBAoMGEludGVybmV0IFdpZGdp
dHMgUHR5IEx0ZDAeFw0xNDA0MjMyMzIxNTdaFw0xNDA1MjMyMzIxNTdaMEUxCzAJ
BgNVBAYTAkFVMRMwEQYDVQQIDApTb21lLVN0YXRlMSEwHwYDVQQKDBhJbnRlcm5l
dCBXaWRnaXRzIFB0eSBMdGQwWTATBgcqhkjOPQIBBggqhkjOPQMBBwNCAATmK2ni
v2Wfl74vHg2UikzVl2u3qR4NRvvdqakendy6WgHn1peoChj5w8SjHlbifINI2xYa
HPUdfvGULUvPciLBMAkGByqGSM49BAEDSAAwRQIhAPKgNV5ROjbDgnmb7idQhY5w
BnSVV9IpdAD0vhWHXcQHAiB8HnkUaiGD8Hp0aHlfFJmaaLTxy54VXuYfMlJhXnXJ
FA==
-----END CERTIFICATE-----
)";

// kNegativeVersionPEM is an X.509 certificate with a negative version number.
static const char kNegativeVersionPEM[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// kFutureVersionPEM is an X.509 certificate with a version number value of
// three, which is not defined. (v3 has value two).
static const char kFutureVersionPEM[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// kOverflowVersionPEM is an X.509 certificate with a version field which
// overflows `uint64_t`.
static const char kOverflowVersionPEM[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// kV1WithExtensionsPEM is an X.509v1 certificate with extensions.
static const char kV1WithExtensionsPEM[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// kV2WithExtensionsPEM is an X.509v2 certificate with extensions.
static const char kV2WithExtensionsPEM[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// kV1WithIssuerUniqueIDPEM is an X.509v1 certificate with an issuerUniqueID.
static const char kV1WithIssuerUniqueIDPEM[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// kV1WithSubjectUniqueIDPEM is an X.509v1 certificate with an issuerUniqueID.
static const char kV1WithSubjectUniqueIDPEM[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// kV1CRLWithExtensionsPEM is a v1 CRL with extensions.
static const char kV1CRLWithExtensionsPEM[] = R"(
-----BEGIN X509 CRL-----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-----END X509 CRL-----
)";

// kV1CRLWithEntryExtensionsPEM is a v1 CRL with entry extensions.
static const char kV1CRLWithEntryExtensionsPEM[] = R"(
-----BEGIN X509 CRL-----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-----END X509 CRL-----
)";

// kExplicitDefaultVersionCRLPEM is a v1 CRL with an explicitly-encoded version
// field.
static const char kExplicitDefaultVersionCRLPEM[] = R"(
-----BEGIN X509 CRL-----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-----END X509 CRL-----
)";

// kV3CRLPEM is a v3 CRL. CRL versions only go up to v2.
static const char kV3CRLPEM[] = R"(
-----BEGIN X509 CRL-----
MIIBpzCBkAIBAjANBgkqhkiG9w0BAQsFADBOMQswCQYDVQQGEwJVUzETMBEGA1UE
CAwKQ2FsaWZvcm5pYTEWMBQGA1UEBwwNTW91bnRhaW4gVmlldzESMBAGA1UECgwJ
Qm9yaW5nU1NMFw0xNjA5MjYxNTEwNTVaFw0xNjEwMjYxNTEwNTVaoA4wDDAKBgNV
HRQEAwIBATANBgkqhkiG9w0BAQsFAAOCAQEAnrBKKgvd9x9zwK9rtUvVeFeJ7+LN
ZEAc+a5oxpPNEsJx6hXoApYEbzXMxuWBQoCs5iEBycSGudct21L+MVf27M38KrWo
eOkq0a2siqViQZO2Fb/SUFR0k9zb8xl86Zf65lgPplALun0bV/HT7MJcl04Tc4os
dsAReBs5nqTGNEd5AlC1iKHvQZkM//MD51DspKnDpsDiUVi54h9C1SpfZmX8H2Vv
diyu0fZ/bPAM3VAGawatf/SyWfBMyKpoPXEG39oAzmjjOj8en82psn7m474IGaho
/vBbhl1ms5qQiLYPjm4YELtnXQoFyC72tBjbdFd/ZE9k4CNKDbxFUXFbkw==
-----END X509 CRL-----
)";

// kV2CSRPEM is a v2 CSR. CSR versions only go up to v1.
static const char kV2CSRPEM[] = R"(
-----BEGIN CERTIFICATE REQUEST-----
MIHJMHECAQEwDzENMAsGA1UEAwwEVGVzdDBZMBMGByqGSM49AgEGCCqGSM49AwEH
A0IABJjsayyAQod1J7UJYNT8AH4WWxLdKV0ozhrIz6hCzBAze7AqXWOSH8G+1EWC
pSfL3oMQNtBdJS0kpXXaUqEAgTSgADAKBggqhkjOPQQDAgNIADBFAiAUXVaEYATg
4Cc917T73KBImxh6xyhsA5pKuYpq1S4m9wIhAK+G93HR4ur7Ghel6+zUTvIAsj9e
rsn4lSYsqI4OI4ei
-----END CERTIFICATE REQUEST-----
)";

// kV3CSRPEM is a v3 CSR. CSR versions only go up to v1.
static const char kV3CSRPEM[] = R"(
-----BEGIN CERTIFICATE REQUEST-----
MIHJMHECAQIwDzENMAsGA1UEAwwEVGVzdDBZMBMGByqGSM49AgEGCCqGSM49AwEH
A0IABJjsayyAQod1J7UJYNT8AH4WWxLdKV0ozhrIz6hCzBAze7AqXWOSH8G+1EWC
pSfL3oMQNtBdJS0kpXXaUqEAgTSgADAKBggqhkjOPQQDAgNIADBFAiAUXVaEYATg
4Cc917T73KBImxh6xyhsA5pKuYpq1S4m9wIhAK+G93HR4ur7Ghel6+zUTvIAsj9e
rsn4lSYsqI4OI4ei
-----END CERTIFICATE REQUEST-----
)";

// Test that the library enforces versions are valid and match the fields
// present.
TEST(X509Test, InvalidVersion) {
  // kExplicitDefaultVersionPEM is invalid but, for now, we accept it. See
  // https://crbug.com/42290225.
  EXPECT_TRUE(CertFromPEM(kExplicitDefaultVersionPEM));
  EXPECT_FALSE(CRLFromPEM(kExplicitDefaultVersionCRLPEM));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_X509, X509_R_INVALID_VERSION}}));
  EXPECT_FALSE(CertFromPEM(kNegativeVersionPEM));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_ASN1, ASN1_R_DECODE_ERROR}}));
  EXPECT_FALSE(CertFromPEM(kFutureVersionPEM));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_X509, X509_R_INVALID_VERSION}}));
  EXPECT_FALSE(CertFromPEM(kOverflowVersionPEM));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_ASN1, ASN1_R_DECODE_ERROR}}));
  EXPECT_FALSE(CertFromPEM(kV1WithExtensionsPEM));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_ASN1, ASN1_R_DECODE_ERROR}}));
  EXPECT_FALSE(CertFromPEM(kV2WithExtensionsPEM));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_ASN1, ASN1_R_DECODE_ERROR}}));
  EXPECT_FALSE(CertFromPEM(kV1WithIssuerUniqueIDPEM));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_ASN1, ASN1_R_DECODE_ERROR}}));
  EXPECT_FALSE(CertFromPEM(kV1WithSubjectUniqueIDPEM));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_ASN1, ASN1_R_DECODE_ERROR}}));
  EXPECT_FALSE(CRLFromPEM(kV1CRLWithExtensionsPEM));
  EXPECT_TRUE(
      ErrorsAreAndClear({{ERR_LIB_X509, X509_R_INVALID_FIELD_FOR_VERSION}}));
  EXPECT_FALSE(CRLFromPEM(kV1CRLWithEntryExtensionsPEM));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_X509, X509_R_INVALID_VERSION}}));
  EXPECT_FALSE(CRLFromPEM(kV3CRLPEM));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_X509, X509_R_INVALID_VERSION}}));
  EXPECT_FALSE(CSRFromPEM(kV2CSRPEM));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_X509, X509_R_INVALID_VERSION}}));

  // kV3CSRPEM is invalid but, for now, we accept it. See
  // https://github.com/certbot/certbot/pull/9334
  EXPECT_TRUE(CSRFromPEM(kV3CSRPEM));

  UniquePtr<X509> x509(X509_new());
  ASSERT_TRUE(x509);
  EXPECT_FALSE(X509_set_version(x509.get(), -1));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_X509, X509_R_INVALID_VERSION}}));
  EXPECT_FALSE(X509_set_version(x509.get(), X509_VERSION_3 + 1));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_X509, X509_R_INVALID_VERSION}}));
  EXPECT_FALSE(X509_set_version(x509.get(), 9999));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_X509, X509_R_INVALID_VERSION}}));

  UniquePtr<X509_CRL> crl(X509_CRL_new());
  ASSERT_TRUE(crl);
  EXPECT_FALSE(X509_CRL_set_version(crl.get(), -1));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_X509, X509_R_INVALID_VERSION}}));
  EXPECT_FALSE(X509_CRL_set_version(crl.get(), X509_CRL_VERSION_2 + 1));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_X509, X509_R_INVALID_VERSION}}));
  EXPECT_FALSE(X509_CRL_set_version(crl.get(), 9999));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_X509, X509_R_INVALID_VERSION}}));

  UniquePtr<X509_REQ> req(X509_REQ_new());
  ASSERT_TRUE(req);
  EXPECT_FALSE(X509_REQ_set_version(req.get(), -1));
  EXPECT_FALSE(X509_REQ_set_version(req.get(), X509_REQ_VERSION_1 + 1));
  EXPECT_FALSE(X509_REQ_set_version(req.get(), 9999));
}

// kCRLEmptyExtension is a CRL with an empty extension list.
static const char kCRLEmptyExtensionPEM[] = R"(
-----BEGIN X509 CRL-----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-----END X509 CRL-----
)";

// kCRLEmptyEntryExtension is a CRL with an entry with an empty extension list.
static const char kCRLEmptyEntryExtensionPEM[] = R"(
-----BEGIN X509 CRL-----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==
-----END X509 CRL-----
)";


// Test that the library rejects empty extension lists in CRLs.
TEST(X509Test, EmptyCRLExtensions) {
  EXPECT_FALSE(CRLFromPEM(kCRLEmptyExtensionPEM));
  EXPECT_FALSE(CRLFromPEM(kCRLEmptyEntryExtensionPEM));
}

// Unlike upstream OpenSSL, we require a non-null store in
// `X509_STORE_CTX_init`.
TEST(X509Test, NullStore) {
  UniquePtr<X509> leaf(CertFromPEM(kLeafPEM));
  ASSERT_TRUE(leaf);
  UniquePtr<X509_STORE_CTX> ctx(X509_STORE_CTX_new());
  ASSERT_TRUE(ctx);
  EXPECT_FALSE(X509_STORE_CTX_init(ctx.get(), nullptr, leaf.get(), nullptr));
}

TEST(X509Test, StoreCtxReuse) {
  UniquePtr<X509> leaf(CertFromPEM(kLeafPEM));
  ASSERT_TRUE(leaf);
  UniquePtr<X509_STORE> store(X509_STORE_new());
  ASSERT_TRUE(store);
  UniquePtr<X509_STORE_CTX> ctx(X509_STORE_CTX_new());
  ASSERT_TRUE(ctx);
  ASSERT_TRUE(X509_STORE_CTX_init(ctx.get(), store.get(), leaf.get(), nullptr));
  // Re-initializing `ctx` should not leak memory.
  ASSERT_TRUE(X509_STORE_CTX_init(ctx.get(), store.get(), leaf.get(), nullptr));
}

TEST(X509Test, BasicConstraints) {
  const uint32_t kFlagMask = EXFLAG_CA | EXFLAG_BCONS | EXFLAG_INVALID;

  static const struct {
    const char *file;
    uint32_t flags;
    int path_len;
  } kTests[] = {
      {"basic_constraints_none.pem", 0, -1},
      {"basic_constraints_ca.pem", EXFLAG_CA | EXFLAG_BCONS, -1},
      {"basic_constraints_ca_pathlen_0.pem", EXFLAG_CA | EXFLAG_BCONS, 0},
      {"basic_constraints_ca_pathlen_1.pem", EXFLAG_CA | EXFLAG_BCONS, 1},
      {"basic_constraints_ca_pathlen_10.pem", EXFLAG_CA | EXFLAG_BCONS, 10},
      {"basic_constraints_leaf.pem", EXFLAG_BCONS, -1},
      {"invalid_extension_leaf_basic_constraints.pem", EXFLAG_INVALID, -1},
  };

  for (const auto &test : kTests) {
    SCOPED_TRACE(test.file);

    std::string path = "crypto/x509/test/";
    path += test.file;

    UniquePtr<X509> cert = CertFromPEM(GetTestData(path.c_str()));
    ASSERT_TRUE(cert);
    EXPECT_EQ(test.flags, X509_get_extension_flags(cert.get()) & kFlagMask);
    EXPECT_EQ(test.path_len, X509_get_pathlen(cert.get()));
  }
}

// The following strings are test certificates signed by kP256Key and kRSAKey,
// with missing, NULL, or invalid algorithm parameters.
static const char kP256NoParam[] = R"(
-----BEGIN CERTIFICATE-----
MIIBIDCBxqADAgECAgIE0jAKBggqhkjOPQQDAjAPMQ0wCwYDVQQDEwRUZXN0MCAX
DTAwMDEwMTAwMDAwMFoYDzIxMDAwMTAxMDAwMDAwWjAPMQ0wCwYDVQQDEwRUZXN0
MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE5itp4r9ln5e+Lx4NlIpM1Zdrt6ke
DUb73ampHp3culoB59aXqAoY+cPEox5W4nyDSNsWGhz1HX7xlC1Lz3IiwaMQMA4w
DAYDVR0TBAUwAwEB/zAKBggqhkjOPQQDAgNJADBGAiEAqdIiF+bN9Cl44oUeICpy
aXd7HqhpVUaglYKw9ChmNUACIQCpMdL0fNkFNDbRww9dSl/y7kBdk/tp16HiqeSy
gGzFYg==
-----END CERTIFICATE-----
)";
static const char kP256NullParam[] = R"(
-----BEGIN CERTIFICATE-----
MIIBJDCByKADAgECAgIE0jAMBggqhkjOPQQDAgUAMA8xDTALBgNVBAMTBFRlc3Qw
IBcNMDAwMTAxMDAwMDAwWhgPMjEwMDAxMDEwMDAwMDBaMA8xDTALBgNVBAMTBFRl
c3QwWTATBgcqhkjOPQIBBggqhkjOPQMBBwNCAATmK2niv2Wfl74vHg2UikzVl2u3
qR4NRvvdqakendy6WgHn1peoChj5w8SjHlbifINI2xYaHPUdfvGULUvPciLBoxAw
DjAMBgNVHRMEBTADAQH/MAwGCCqGSM49BAMCBQADSQAwRgIhAKILHmyo+F3Cn/VX
UUeSXOQQKX5aLzsQitwwmNF3ZgH3AiEAsYHcrVj/ftmoQIORARkQ/+PrqntXev8r
t6uPxHrmpUY=
-----END CERTIFICATE-----
)";
static const char kP256InvalidParam[] = R"(
-----BEGIN CERTIFICATE-----
MIIBMTCBz6ADAgECAgIE0jATBggqhkjOPQQDAgQHZ2FyYmFnZTAPMQ0wCwYDVQQD
EwRUZXN0MCAXDTAwMDEwMTAwMDAwMFoYDzIxMDAwMTAxMDAwMDAwWjAPMQ0wCwYD
VQQDEwRUZXN0MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE5itp4r9ln5e+Lx4N
lIpM1Zdrt6keDUb73ampHp3culoB59aXqAoY+cPEox5W4nyDSNsWGhz1HX7xlC1L
z3IiwaMQMA4wDAYDVR0TBAUwAwEB/zATBggqhkjOPQQDAgQHZ2FyYmFnZQNIADBF
AiAglpDf/YhN89LeJ2WAs/F0SJIrsuhS4uoInIz6WXUiuQIhAIu5Pwhp5E3Pbo8y
fLULTZnynuQUULQkRcF7S7T2WpIL
-----END CERTIFICATE-----
)";
static const char kRSANoParam[] = R"(
-----BEGIN CERTIFICATE-----
MIIBWzCBx6ADAgECAgIE0jALBgkqhkiG9w0BAQswDzENMAsGA1UEAxMEVGVzdDAg
Fw0wMDAxMDEwMDAwMDBaGA8yMTAwMDEwMTAwMDAwMFowDzENMAsGA1UEAxMEVGVz
dDBZMBMGByqGSM49AgEGCCqGSM49AwEHA0IABOYraeK/ZZ+Xvi8eDZSKTNWXa7ep
Hg1G+92pqR6d3LpaAefWl6gKGPnDxKMeVuJ8g0jbFhoc9R1+8ZQtS89yIsGjEDAO
MAwGA1UdEwQFMAMBAf8wCwYJKoZIhvcNAQELA4GBAC1f8W3W0Ao7CPfIBQYDSbPh
brZpbxdBU5x27JOS7iSa+Lc9pEH5VCX9vIypHVHXLPEfZ38yIt11eiyrmZB6w62N
l9kIeZ6FVPmC30d3sXx70Jjs+ZX9yt7kD1gLyNAQQfeYfa4rORAZT1n2YitD74NY
TWUH2ieFP3l+ecj1SeQR
-----END CERTIFICATE-----
)";
static const char kRSANullParam[] = R"(
-----BEGIN CERTIFICATE-----
MIIBXzCByaADAgECAgIE0jANBgkqhkiG9w0BAQsFADAPMQ0wCwYDVQQDEwRUZXN0
MCAXDTAwMDEwMTAwMDAwMFoYDzIxMDAwMTAxMDAwMDAwWjAPMQ0wCwYDVQQDEwRU
ZXN0MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE5itp4r9ln5e+Lx4NlIpM1Zdr
t6keDUb73ampHp3culoB59aXqAoY+cPEox5W4nyDSNsWGhz1HX7xlC1Lz3IiwaMQ
MA4wDAYDVR0TBAUwAwEB/zANBgkqhkiG9w0BAQsFAAOBgQAzVcfIv+Rq1KrMXqIL
fPq/cWZjgqFZA1RGaGElNaqp+rkJfamq5tDGzckWpebrK+jjRN7yIlcWDtPpy3Gy
seZfvtBDR0TwJm0S/pQl8prKB4wgALcwe3bmi56Rq85nzY5ZLNcP16LQxL+jAAua
SwmQUz4bRpckRBj+sIyp1We+pg==
-----END CERTIFICATE-----
)";
static const char kRSAInvalidParam[] = R"(
-----BEGIN CERTIFICATE-----
MIIBbTCB0KADAgECAgIE0jAUBgkqhkiG9w0BAQsEB2dhcmJhZ2UwDzENMAsGA1UE
AxMEVGVzdDAgFw0wMDAxMDEwMDAwMDBaGA8yMTAwMDEwMTAwMDAwMFowDzENMAsG
A1UEAxMEVGVzdDBZMBMGByqGSM49AgEGCCqGSM49AwEHA0IABOYraeK/ZZ+Xvi8e
DZSKTNWXa7epHg1G+92pqR6d3LpaAefWl6gKGPnDxKMeVuJ8g0jbFhoc9R1+8ZQt
S89yIsGjEDAOMAwGA1UdEwQFMAMBAf8wFAYJKoZIhvcNAQELBAdnYXJiYWdlA4GB
AHTJ6cWWjCNrZhqiWWVI3jdK+h5xpRG8jGMXxR4JnjtoYRRusJLOXhmapwCB6fA0
4vc+66O27v36yDmQX+tIc/hDrTpKNJptU8q3n2VagREvoHhkOTYkcCeS8vmnMtn8
5OMNZ/ajVwOssw61GcAlScRqEHkZFBoGp7e+QpgB2tf9
-----END CERTIFICATE-----
)";

TEST(X509Test, AlgorithmParameters) {
  // P-256 parameters should be omitted, but we accept NULL ones.
  UniquePtr<EVP_PKEY> key = PrivateKeyFromPEM(kP256Key);
  ASSERT_TRUE(key);

  UniquePtr<X509> cert = CertFromPEM(kP256NoParam);
  ASSERT_TRUE(cert);
  EXPECT_TRUE(X509_verify(cert.get(), key.get()));

  cert = CertFromPEM(kP256NullParam);
  ASSERT_TRUE(cert);
  EXPECT_TRUE(X509_verify(cert.get(), key.get()));

  cert = CertFromPEM(kP256InvalidParam);
  ASSERT_TRUE(cert);
  EXPECT_FALSE(X509_verify(cert.get(), key.get()));
  EXPECT_TRUE(
      ErrorEquals(ERR_get_error(), ERR_LIB_X509, X509_R_INVALID_PARAMETER));

  // RSA parameters should be NULL, but we accept omitted ones.
  key = PrivateKeyFromPEM(kRSAKey);
  ASSERT_TRUE(key);

  cert = CertFromPEM(kRSANoParam);
  ASSERT_TRUE(cert);
  EXPECT_TRUE(X509_verify(cert.get(), key.get()));

  cert = CertFromPEM(kRSANullParam);
  ASSERT_TRUE(cert);
  EXPECT_TRUE(X509_verify(cert.get(), key.get()));

  cert = CertFromPEM(kRSAInvalidParam);
  ASSERT_TRUE(cert);
  EXPECT_FALSE(X509_verify(cert.get(), key.get()));
  EXPECT_TRUE(
      ErrorEquals(ERR_get_error(), ERR_LIB_X509, X509_R_INVALID_PARAMETER));
}

TEST(X509Test, GeneralName) {
  const std::vector<uint8_t> kNames[] = {
      // [0] {
      //   OBJECT_IDENTIFIER { 1.2.840.113554.4.1.72585.2.1 }
      //   [0] {
      //     SEQUENCE {}
      //   }
      // }
      {0xa0, 0x13, 0x06, 0x0d, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
       0x01, 0x84, 0xb7, 0x09, 0x02, 0x01, 0xa0, 0x02, 0x30, 0x00},
      // [0] {
      //   OBJECT_IDENTIFIER { 1.2.840.113554.4.1.72585.2.1 }
      //   [0] {
      //     [APPLICATION 0] {}
      //   }
      // }
      {0xa0, 0x13, 0x06, 0x0d, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
       0x01, 0x84, 0xb7, 0x09, 0x02, 0x01, 0xa0, 0x02, 0x60, 0x00},
      // [0] {
      //   OBJECT_IDENTIFIER { 1.2.840.113554.4.1.72585.2.1 }
      //   [0] {
      //     UTF8String { "a" }
      //   }
      // }
      {0xa0, 0x14, 0x06, 0x0d, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
       0x01, 0x84, 0xb7, 0x09, 0x02, 0x01, 0xa0, 0x03, 0x0c, 0x01, 0x61},
      // [0] {
      //   OBJECT_IDENTIFIER { 1.2.840.113554.4.1.72585.2.2 }
      //   [0] {
      //     UTF8String { "a" }
      //   }
      // }
      {0xa0, 0x14, 0x06, 0x0d, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
       0x01, 0x84, 0xb7, 0x09, 0x02, 0x02, 0xa0, 0x03, 0x0c, 0x01, 0x61},
      // [0] {
      //   OBJECT_IDENTIFIER { 1.2.840.113554.4.1.72585.2.1 }
      //   [0] {
      //     UTF8String { "b" }
      //   }
      // }
      {0xa0, 0x14, 0x06, 0x0d, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
       0x01, 0x84, 0xb7, 0x09, 0x02, 0x01, 0xa0, 0x03, 0x0c, 0x01, 0x62},
      // [0] {
      //   OBJECT_IDENTIFIER { 1.2.840.113554.4.1.72585.2.1 }
      //   [0] {
      //     BOOLEAN { TRUE }
      //   }
      // }
      {0xa0, 0x14, 0x06, 0x0d, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
       0x01, 0x84, 0xb7, 0x09, 0x02, 0x01, 0xa0, 0x03, 0x01, 0x01, 0xff},
      // [0] {
      //   OBJECT_IDENTIFIER { 1.2.840.113554.4.1.72585.2.1 }
      //   [0] {
      //     BOOLEAN { FALSE }
      //   }
      // }
      {0xa0, 0x14, 0x06, 0x0d, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
       0x01, 0x84, 0xb7, 0x09, 0x02, 0x01, 0xa0, 0x03, 0x01, 0x01, 0x00},
      // [1 PRIMITIVE] { "a" }
      {0x81, 0x01, 0x61},
      // [1 PRIMITIVE] { "b" }
      {0x81, 0x01, 0x62},
      // [2 PRIMITIVE] { "a" }
      {0x82, 0x01, 0x61},
      // [2 PRIMITIVE] { "b" }
      {0x82, 0x01, 0x62},
      // [3] {}
      {0xa3, 0x00},
      // [4] {
      //   SEQUENCE {
      //     SET {
      //       SEQUENCE {
      //         # commonName
      //         OBJECT_IDENTIFIER { 2.5.4.3 }
      //         UTF8String { "a" }
      //       }
      //     }
      //   }
      // }
      {0xa4, 0x0e, 0x30, 0x0c, 0x31, 0x0a, 0x30, 0x08, 0x06, 0x03, 0x55, 0x04,
       0x03, 0x0c, 0x01, 0x61},
      // [4] {
      //   SEQUENCE {
      //     SET {
      //       SEQUENCE {
      //         # commonName
      //         OBJECT_IDENTIFIER { 2.5.4.3 }
      //         UTF8String { "b" }
      //       }
      //     }
      //   }
      // }
      {0xa4, 0x0e, 0x30, 0x0c, 0x31, 0x0a, 0x30, 0x08, 0x06, 0x03, 0x55, 0x04,
       0x03, 0x0c, 0x01, 0x62},
      // [5] {
      //   [1] {
      //     UTF8String { "a" }
      //   }
      // }
      {0xa5, 0x05, 0xa1, 0x03, 0x0c, 0x01, 0x61},
      // [5] {
      //   [1] {
      //     UTF8String { "b" }
      //   }
      // }
      {0xa5, 0x05, 0xa1, 0x03, 0x0c, 0x01, 0x62},
      // [5] {
      //   [0] {
      //     UTF8String {}
      //   }
      //   [1] {
      //     UTF8String { "a" }
      //   }
      // }
      {0xa5, 0x09, 0xa0, 0x02, 0x0c, 0x00, 0xa1, 0x03, 0x0c, 0x01, 0x61},
      // [5] {
      //   [0] {
      //     UTF8String { "a" }
      //   }
      //   [1] {
      //     UTF8String { "a" }
      //   }
      // }
      {0xa5, 0x0a, 0xa0, 0x03, 0x0c, 0x01, 0x61, 0xa1, 0x03, 0x0c, 0x01, 0x61},
      // [5] {
      //   [0] {
      //     UTF8String { "b" }
      //   }
      //   [1] {
      //     UTF8String { "a" }
      //   }
      // }
      {0xa5, 0x0a, 0xa0, 0x03, 0x0c, 0x01, 0x62, 0xa1, 0x03, 0x0c, 0x01, 0x61},
      // [6 PRIMITIVE] { "a" }
      {0x86, 0x01, 0x61},
      // [6 PRIMITIVE] { "b" }
      {0x86, 0x01, 0x62},
      // [7 PRIMITIVE] { `11111111` }
      {0x87, 0x04, 0x11, 0x11, 0x11, 0x11},
      // [7 PRIMITIVE] { `22222222`}
      {0x87, 0x04, 0x22, 0x22, 0x22, 0x22},
      // [7 PRIMITIVE] { `11111111111111111111111111111111` }
      {0x87, 0x10, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11,
       0x11, 0x11, 0x11, 0x11, 0x11, 0x11},
      // [7 PRIMITIVE] { `22222222222222222222222222222222` }
      {0x87, 0x10, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22,
       0x22, 0x22, 0x22, 0x22, 0x22, 0x22},
      // [8 PRIMITIVE] { 1.2.840.113554.4.1.72585.2.1 }
      {0x88, 0x0d, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04, 0x01, 0x84, 0xb7,
       0x09, 0x02, 0x01},
      // [8 PRIMITIVE] { 1.2.840.113554.4.1.72585.2.2 }
      {0x88, 0x0d, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04, 0x01, 0x84, 0xb7,
       0x09, 0x02, 0x02},
  };

  // Every name should be equal to itself and not equal to any others.
  for (size_t i = 0; i < std::size(kNames); i++) {
    SCOPED_TRACE(Bytes(kNames[i]));

    const uint8_t *ptr = kNames[i].data();
    UniquePtr<GENERAL_NAME> a(
        d2i_GENERAL_NAME(nullptr, &ptr, kNames[i].size()));
    ASSERT_TRUE(a);
    ASSERT_EQ(ptr, kNames[i].data() + kNames[i].size());

    uint8_t *enc = nullptr;
    int enc_len = i2d_GENERAL_NAME(a.get(), &enc);
    ASSERT_GE(enc_len, 0);
    UniquePtr<uint8_t> free_enc(enc);
    EXPECT_EQ(Bytes(enc, enc_len), Bytes(kNames[i]));

    for (size_t j = 0; j < std::size(kNames); j++) {
      SCOPED_TRACE(Bytes(kNames[j]));

      ptr = kNames[j].data();
      UniquePtr<GENERAL_NAME> b(
          d2i_GENERAL_NAME(nullptr, &ptr, kNames[j].size()));
      ASSERT_TRUE(b);
      ASSERT_EQ(ptr, kNames[j].data() + kNames[j].size());

      if (i == j) {
        EXPECT_EQ(GENERAL_NAME_cmp(a.get(), b.get()), 0);
      } else {
        EXPECT_NE(GENERAL_NAME_cmp(a.get(), b.get()), 0);
      }
    }
  }
}

// Test that extracting fields of an `X509_ALGOR` works correctly.
TEST(X509Test, X509AlgorExtract) {
  static const char kTestOID[] = "1.2.840.113554.4.1.72585.2";
  const struct {
    int param_type;
    std::vector<uint8_t> param_der;
  } kTests[] = {
      // No parameter.
      {V_ASN1_UNDEF, {}},
      // BOOLEAN { TRUE }
      {V_ASN1_BOOLEAN, {0x01, 0x01, 0xff}},
      // BOOLEAN { FALSE }
      {V_ASN1_BOOLEAN, {0x01, 0x01, 0x00}},
      // OCTET_STRING { "a" }
      {V_ASN1_OCTET_STRING, {0x04, 0x01, 0x61}},
      // BIT_STRING { `01` `00` }
      {V_ASN1_BIT_STRING, {0x03, 0x02, 0x01, 0x00}},
      // INTEGER { -1 }
      {V_ASN1_INTEGER, {0x02, 0x01, 0xff}},
      // OBJECT_IDENTIFIER { 1.2.840.113554.4.1.72585.2 }
      {V_ASN1_OBJECT,
       {0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04, 0x01, 0x84, 0xb7,
        0x09, 0x02}},
      // NULL {}
      {V_ASN1_NULL, {0x05, 0x00}},
      // SEQUENCE {}
      {V_ASN1_SEQUENCE, {0x30, 0x00}},
      // SET {}
      {V_ASN1_SET, {0x31, 0x00}},
      // [0] { UTF8String { "a" } }
      {V_ASN1_OTHER, {0xa0, 0x03, 0x0c, 0x01, 0x61}},
  };
  for (const auto &t : kTests) {
    SCOPED_TRACE(Bytes(t.param_der));

    // Assemble an AlgorithmIdentifier with the parameter.
    ScopedCBB cbb;
    CBB seq, oid;
    ASSERT_TRUE(CBB_init(cbb.get(), 64));
    ASSERT_TRUE(CBB_add_asn1(cbb.get(), &seq, CBS_ASN1_SEQUENCE));
    ASSERT_TRUE(CBB_add_asn1(&seq, &oid, CBS_ASN1_OBJECT));
    ASSERT_TRUE(CBB_add_asn1_oid_from_text(&oid, kTestOID, strlen(kTestOID)));
    ASSERT_TRUE(CBB_add_bytes(&seq, t.param_der.data(), t.param_der.size()));
    ASSERT_TRUE(CBB_flush(cbb.get()));

    const uint8_t *ptr = CBB_data(cbb.get());
    UniquePtr<X509_ALGOR> alg(
        d2i_X509_ALGOR(nullptr, &ptr, CBB_len(cbb.get())));
    ASSERT_TRUE(alg);

    const ASN1_OBJECT *obj;
    int param_type;
    const void *param_value;
    X509_ALGOR_get0(&obj, &param_type, &param_value, alg.get());

    EXPECT_EQ(param_type, t.param_type);
    char oid_buf[sizeof(kTestOID)];
    ASSERT_EQ(int(sizeof(oid_buf) - 1),
              OBJ_obj2txt(oid_buf, sizeof(oid_buf), obj,
                          /*always_return_oid=*/1));
    EXPECT_STREQ(oid_buf, kTestOID);

    // `param_type` and `param_value` must be consistent with `ASN1_TYPE`.
    if (param_type == V_ASN1_UNDEF) {
      EXPECT_EQ(nullptr, param_value);
    } else {
      UniquePtr<ASN1_TYPE> param(ASN1_TYPE_new());
      ASSERT_TRUE(param);
      ASSERT_TRUE(ASN1_TYPE_set1(param.get(), param_type, param_value));

      uint8_t *param_der = nullptr;
      int param_len = i2d_ASN1_TYPE(param.get(), &param_der);
      ASSERT_GE(param_len, 0);
      UniquePtr<uint8_t> free_param_der(param_der);

      EXPECT_EQ(Bytes(param_der, param_len), Bytes(t.param_der));
    }
  }
}

// Test the various `X509_ATTRIBUTE` creation functions.
TEST(X509Test, Attribute) {
  // The expected attribute values are:
  // 1. BMPString U+2603
  // 2. BMPString "test"
  // 3. INTEGER -1 (not valid for friendlyName)
  static const uint8_t kTest1[] = {0x26, 0x03};  // U+2603 SNOWMAN
  static const uint8_t kTest1UTF8[] = {0xe2, 0x98, 0x83};
  static const uint8_t kTest2[] = {0, 't', 0, 'e', 0, 's', 0, 't'};

  constexpr uint32_t kTest1Mask = 1 << 0;
  constexpr uint32_t kTest2Mask = 1 << 1;
  constexpr uint32_t kTest3Mask = 1 << 2;
  auto check_attribute = [&](X509_ATTRIBUTE *attr, uint32_t mask) {
    EXPECT_EQ(NID_friendlyName, OBJ_obj2nid(X509_ATTRIBUTE_get0_object(attr)));

    int idx = 0;
    if (mask & kTest1Mask) {
      // The first attribute should contain `kTest1`.
      const ASN1_TYPE *value = X509_ATTRIBUTE_get0_type(attr, idx);
      ASSERT_TRUE(value);
      EXPECT_EQ(V_ASN1_BMPSTRING, value->type);
      EXPECT_EQ(Bytes(kTest1),
                Bytes(ASN1StringAsBytes(value->value.bmpstring)));

      // `X509_ATTRIBUTE_get0_data` requires the type match.
      EXPECT_FALSE(
          X509_ATTRIBUTE_get0_data(attr, idx, V_ASN1_OCTET_STRING, nullptr));
      EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_X509, X509_R_WRONG_TYPE}}));
      const ASN1_BMPSTRING *bmpstring = static_cast<const ASN1_BMPSTRING *>(
          X509_ATTRIBUTE_get0_data(attr, idx, V_ASN1_BMPSTRING, nullptr));
      ASSERT_TRUE(bmpstring);
      EXPECT_EQ(Bytes(kTest1), Bytes(ASN1StringAsBytes(bmpstring)));
      idx++;
    }

    if (mask & kTest2Mask) {
      const ASN1_TYPE *value = X509_ATTRIBUTE_get0_type(attr, idx);
      ASSERT_TRUE(value);
      EXPECT_EQ(V_ASN1_BMPSTRING, value->type);
      EXPECT_EQ(Bytes(kTest2),
                Bytes(ASN1StringAsBytes(value->value.bmpstring)));
      idx++;
    }

    if (mask & kTest3Mask) {
      const ASN1_TYPE *value = X509_ATTRIBUTE_get0_type(attr, idx);
      ASSERT_TRUE(value);
      EXPECT_EQ(V_ASN1_INTEGER, value->type);
      int64_t v;
      ASSERT_TRUE(ASN1_INTEGER_get_int64(&v, value->value.integer));
      EXPECT_EQ(v, -1);
      idx++;
    }

    EXPECT_FALSE(X509_ATTRIBUTE_get0_type(attr, idx));
  };

  UniquePtr<ASN1_STRING> str(ASN1_STRING_type_new(V_ASN1_BMPSTRING));
  ASSERT_TRUE(str);
  ASSERT_TRUE(ASN1_STRING_set(str.get(), kTest1, sizeof(kTest1)));

  // Test `X509_ATTRIBUTE_create`.
  UniquePtr<X509_ATTRIBUTE> attr(
      X509_ATTRIBUTE_create(NID_friendlyName, V_ASN1_BMPSTRING, str.get()));
  ASSERT_TRUE(attr);
  str.release();  // `X509_ATTRIBUTE_create` takes ownership on success.
  check_attribute(attr.get(), kTest1Mask);

  // Test the `MBSTRING_*` form of `X509_ATTRIBUTE_set1_data`.
  attr.reset(X509_ATTRIBUTE_new());
  ASSERT_TRUE(attr);
  ASSERT_TRUE(
      X509_ATTRIBUTE_set1_object(attr.get(), OBJ_nid2obj(NID_friendlyName)));
  ASSERT_TRUE(X509_ATTRIBUTE_set1_data(attr.get(), MBSTRING_UTF8, kTest1UTF8,
                                       sizeof(kTest1UTF8)));
  check_attribute(attr.get(), kTest1Mask);

  // Test the `ASN1_STRING` form of `X509_ATTRIBUTE_set1_data`.
  ASSERT_TRUE(X509_ATTRIBUTE_set1_data(attr.get(), V_ASN1_BMPSTRING, kTest2,
                                       sizeof(kTest2)));
  check_attribute(attr.get(), kTest1Mask | kTest2Mask);

  // The `ASN1_STRING` form of `X509_ATTRIBUTE_set1_data` should correctly
  // handle negative integers.
  const uint8_t kOne = 1;
  ASSERT_TRUE(
      X509_ATTRIBUTE_set1_data(attr.get(), V_ASN1_NEG_INTEGER, &kOne, 1));
  check_attribute(attr.get(), kTest1Mask | kTest2Mask | kTest3Mask);

  // Test the `ASN1_TYPE` form of `X509_ATTRIBUTE_set1_data`.
  attr.reset(X509_ATTRIBUTE_new());
  ASSERT_TRUE(attr);
  ASSERT_TRUE(
      X509_ATTRIBUTE_set1_object(attr.get(), OBJ_nid2obj(NID_friendlyName)));
  str.reset(ASN1_STRING_type_new(V_ASN1_BMPSTRING));
  ASSERT_TRUE(str);
  ASSERT_TRUE(ASN1_STRING_set(str.get(), kTest1, sizeof(kTest1)));
  ASSERT_TRUE(
      X509_ATTRIBUTE_set1_data(attr.get(), V_ASN1_BMPSTRING, str.get(), -1));
  check_attribute(attr.get(), kTest1Mask);

  // An `attrtype` of zero leaves the attribute empty.
  attr.reset(X509_ATTRIBUTE_create_by_NID(
      nullptr, NID_friendlyName, /*attrtype=*/0, /*data=*/nullptr, /*len=*/0));
  ASSERT_TRUE(attr);
  check_attribute(attr.get(), 0);
}

// Test that, by default, `X509_V_FLAG_TRUSTED_FIRST` is set, which means we'll
// skip over server-sent expired intermediates when there is a local trust
// anchor that works better.
TEST(X509Test, TrustedFirst) {
  // Generate the following certificates:
  //
  //                     Root 2 (in store, expired)
  //                       |
  // Root 1 (in store)   Root 1 (cross-sign)
  //          \           /
  //          Intermediate
  //                |
  //               Leaf
  UniquePtr<EVP_PKEY> key = PrivateKeyFromPEM(kP256Key);
  ASSERT_TRUE(key);

  UniquePtr<X509> root2 =
      MakeTestCert("Root 2", "Root 2", key.get(), /*is_ca=*/true);
  ASSERT_TRUE(root2);
  ASSERT_TRUE(ASN1_TIME_adj(X509_getm_notAfter(root2.get()), kReferenceTime,
                            /*offset_day=*/0,
                            /*offset_sec=*/-1));
  ASSERT_TRUE(X509_sign(root2.get(), key.get(), EVP_sha256()));

  UniquePtr<X509> root1 =
      MakeTestCert("Root 1", "Root 1", key.get(), /*is_ca=*/true);
  ASSERT_TRUE(root1);
  ASSERT_TRUE(X509_sign(root1.get(), key.get(), EVP_sha256()));

  UniquePtr<X509> root1_cross =
      MakeTestCert("Root 2", "Root 1", key.get(), /*is_ca=*/true);
  ASSERT_TRUE(root1_cross);
  ASSERT_TRUE(X509_sign(root1_cross.get(), key.get(), EVP_sha256()));

  UniquePtr<X509> intermediate =
      MakeTestCert("Root 1", "Intermediate", key.get(), /*is_ca=*/true);
  ASSERT_TRUE(intermediate);
  ASSERT_TRUE(X509_sign(intermediate.get(), key.get(), EVP_sha256()));

  UniquePtr<X509> leaf =
      MakeTestCert("Intermediate", "Leaf", key.get(), /*is_ca=*/false);
  ASSERT_TRUE(leaf);
  ASSERT_TRUE(X509_sign(leaf.get(), key.get(), EVP_sha256()));

  // As a control, confirm that `leaf` -> `intermediate` -> `root1` is valid,
  // but the path through `root1_cross` is expired.
  EXPECT_EQ(X509_V_OK,
            Verify(leaf.get(), {root1.get()}, {intermediate.get()}, {}));
  EXPECT_EQ(X509_V_ERR_CERT_HAS_EXPIRED,
            Verify(leaf.get(), {root2.get()},
                   {intermediate.get(), root1_cross.get()}, {}));

  // By default, we should find the `leaf` -> `intermediate` -> `root2` chain,
  // skipping `root1_cross`.
  EXPECT_EQ(X509_V_OK, Verify(leaf.get(), {root1.get(), root2.get()},
                              {intermediate.get(), root1_cross.get()}, {}));

  // When `X509_V_FLAG_TRUSTED_FIRST` is disabled, we get stuck on the expired
  // intermediate. Note we need the callback to clear the flag. Setting `flags`
  // to zero only skips setting new flags.
  //
  // This test exists to confirm our current behavior, but these modes are just
  // workarounds for not having an actual path-building verifier. If we fix it,
  // this test can be removed.
  EXPECT_EQ(X509_V_ERR_CERT_HAS_EXPIRED,
            Verify(leaf.get(), {root1.get(), root2.get()},
                   {intermediate.get(), root1_cross.get()}, {}, /*flags=*/0,
                   [&](X509_STORE_CTX *ctx) {
                     X509_VERIFY_PARAM *param = X509_STORE_CTX_get0_param(ctx);
                     X509_VERIFY_PARAM_clear_flags(param,
                                                   X509_V_FLAG_TRUSTED_FIRST);
                   }));

  // Even when `X509_V_FLAG_TRUSTED_FIRST` is disabled, if `root2` is not
  // trusted, the alt chains logic recovers the path.
  EXPECT_EQ(
      X509_V_OK,
      Verify(leaf.get(), {root1.get()}, {intermediate.get(), root1_cross.get()},
             {}, /*flags=*/0, [&](X509_STORE_CTX *ctx) {
               X509_VERIFY_PARAM *param = X509_STORE_CTX_get0_param(ctx);
               X509_VERIFY_PARAM_clear_flags(param, X509_V_FLAG_TRUSTED_FIRST);
             }));
}

// Test that notBefore and notAfter checks work correctly.
TEST(X509Test, Expiry) {
  UniquePtr<EVP_PKEY> key = PrivateKeyFromPEM(kP256Key);
  ASSERT_TRUE(key);

  auto make_cert = [&](const char *issuer, const char *subject, bool is_ca,
                       int not_before_offset,
                       int not_after_offset) -> UniquePtr<X509> {
    UniquePtr<X509> cert = MakeTestCert(issuer, subject, key.get(), is_ca);
    if (cert == nullptr ||
        !ASN1_TIME_adj(X509_getm_notBefore(cert.get()), kReferenceTime,
                       /*offset_day=*/not_before_offset,
                       /*offset_sec=*/0) ||
        !ASN1_TIME_adj(X509_getm_notAfter(cert.get()), kReferenceTime,
                       /*offset_day=*/not_after_offset,
                       /*offset_sec=*/0) ||
        !X509_sign(cert.get(), key.get(), EVP_sha256())) {
      return nullptr;
    }
    return cert;
  };

  struct Certs {
    UniquePtr<X509> not_yet_valid, valid, expired;
  };
  auto make_certs = [&](const char *issuer, const char *subject,
                        bool is_ca) -> Certs {
    Certs certs;
    certs.not_yet_valid =
        make_cert(issuer, subject, is_ca, /*not_before_offset=*/1,
                  /*not_after_offset=*/2);
    certs.valid = make_cert(issuer, subject, is_ca, /*not_before_offset=*/-1,
                            /*not_after_offset=*/1);
    certs.expired = make_cert(issuer, subject, is_ca, /*not_before_offset=*/-2,
                              /*not_after_offset=*/-1);
    if (certs.not_yet_valid == nullptr || certs.valid == nullptr ||
        certs.expired == nullptr) {
      return Certs{};
    }
    return certs;
  };

  Certs root = make_certs("Root", "Root", /*is_ca=*/true);
  ASSERT_TRUE(root.valid);
  Certs root_cross = make_certs("Root 2", "Root", /*is_ca=*/true);
  ASSERT_TRUE(root_cross.valid);
  Certs intermediate = make_certs("Root", "Intermediate", /*is_ca=*/true);
  ASSERT_TRUE(intermediate.valid);
  Certs leaf = make_certs("Intermediate", "Leaf", /*is_ca=*/false);
  ASSERT_TRUE(leaf.valid);

  for (bool check_time : {true, false}) {
    SCOPED_TRACE(check_time);
    for (bool partial_chain : {true, false}) {
      SCOPED_TRACE(partial_chain);
      unsigned long flags = 0;
      if (!check_time) {
        flags |= X509_V_FLAG_NO_CHECK_TIME;
      }
      if (partial_chain) {
        flags |= X509_V_FLAG_PARTIAL_CHAIN;
      }

      int not_yet_valid =
          check_time ? X509_V_ERR_CERT_NOT_YET_VALID : X509_V_OK;
      int has_expired = check_time ? X509_V_ERR_CERT_HAS_EXPIRED : X509_V_OK;

      EXPECT_EQ(not_yet_valid,
                Verify(leaf.not_yet_valid.get(), {root.valid.get()},
                       {intermediate.valid.get()}, {}, flags));
      EXPECT_EQ(not_yet_valid,
                Verify(leaf.valid.get(), {root.valid.get()},
                       {intermediate.not_yet_valid.get()}, {}, flags));
      EXPECT_EQ(not_yet_valid,
                Verify(leaf.valid.get(), {root.not_yet_valid.get()},
                       {intermediate.valid.get()}, {}, flags));

      EXPECT_EQ(X509_V_OK, Verify(leaf.valid.get(), {root.valid.get()},
                                  {intermediate.valid.get()}, {}, flags));

      EXPECT_EQ(has_expired, Verify(leaf.expired.get(), {root.valid.get()},
                                    {intermediate.valid.get()}, {}, flags));
      EXPECT_EQ(has_expired, Verify(leaf.valid.get(), {root.valid.get()},
                                    {intermediate.expired.get()}, {}, flags));
      EXPECT_EQ(has_expired, Verify(leaf.valid.get(), {root.expired.get()},
                                    {intermediate.valid.get()}, {}, flags));

      if (!partial_chain) {
        // By default, non-self-signed certificates are not valid trust anchors.
        EXPECT_EQ(X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT,
                  Verify(leaf.valid.get(), {root_cross.valid.get()},
                         {intermediate.valid.get()}, {}, flags));
      } else {
        // `X509_V_FLAG_PARTIAL_CHAIN` allows non-self-signed trust anchors.
        EXPECT_EQ(X509_V_OK, Verify(leaf.valid.get(), {root_cross.valid.get()},
                                    {intermediate.valid.get()}, {}, flags));
        // Expiry of the trust anchor must still be checked.
        EXPECT_EQ(not_yet_valid,
                  Verify(leaf.valid.get(), {root_cross.not_yet_valid.get()},
                         {intermediate.valid.get()}, {}, flags));
        EXPECT_EQ(has_expired,
                  Verify(leaf.valid.get(), {root_cross.expired.get()},
                         {intermediate.valid.get()}, {}, flags));
      }

      // When the trust anchor is the target certificate, expiry should also be
      // checked.
      EXPECT_EQ(X509_V_OK,
                Verify(root.valid.get(), {root.valid.get()}, {}, {}, flags));
      EXPECT_EQ(not_yet_valid,
                Verify(root.not_yet_valid.get(), {root.not_yet_valid.get()}, {},
                       {}, flags));
      EXPECT_EQ(has_expired, Verify(root.expired.get(), {root.expired.get()},
                                    {}, {}, flags));
    }
  }

  // X509_V_FLAG_USE_CHECK_TIME is an internal flag, but one caller relies on
  // being able to clear it to restore the system time. Using the system time,
  // all certificates in this test should read as expired.
  EXPECT_EQ(X509_V_ERR_CERT_HAS_EXPIRED,
            Verify(leaf.valid.get(), {root.valid.get()},
                   {intermediate.valid.get()}, {}, 0, [](X509_STORE_CTX *ctx) {
                     X509_VERIFY_PARAM *param = X509_STORE_CTX_get0_param(ctx);
                     X509_VERIFY_PARAM_clear_flags(param,
                                                   X509_V_FLAG_USE_CHECK_TIME);
                   }));
}

TEST(X509Test, SignatureVerification) {
  UniquePtr<EVP_PKEY> key = PrivateKeyFromPEM(kP256Key);
  ASSERT_TRUE(key);

  struct Certs {
    UniquePtr<X509> valid;
    UniquePtr<X509> bad_key_type, bad_key;
    UniquePtr<X509> bad_sig_type, bad_sig;
  };
  auto make_certs = [&](const char *issuer, const char *subject,
                        bool is_ca) -> Certs {
    Certs certs;
    certs.valid = MakeTestCert(issuer, subject, key.get(), is_ca);
    if (certs.valid == nullptr ||
        !X509_sign(certs.valid.get(), key.get(), EVP_sha256())) {
      return Certs{};
    }

    static const uint8_t kInvalid[] = {'i', 'n', 'v', 'a', 'l', 'i', 'd'};

    // Extracting the algorithm identifier from `certs.valid`'s SPKI, with
    // OpenSSL's API, is very tedious. Instead, we'll just rely on knowing it is
    // ecPublicKey with P-256 as parameters.
    const ASN1_BIT_STRING *pubkey = X509_get0_pubkey_bitstr(certs.valid.get());
    int pubkey_len = ASN1_STRING_length(pubkey);

    // Sign a copy of the certificate where the key type is an unsupported OID.
    UniquePtr<uint8_t> pubkey_data(static_cast<uint8_t *>(
        OPENSSL_memdup(ASN1_STRING_get0_data(pubkey), pubkey_len)));
    certs.bad_key_type = MakeTestCert(issuer, subject, key.get(), is_ca);
    if (pubkey_data == nullptr || certs.bad_key_type == nullptr ||
        !X509_PUBKEY_set0_param(X509_get_X509_PUBKEY(certs.bad_key_type.get()),
                                OBJ_nid2obj(NID_subject_alt_name), V_ASN1_UNDEF,
                                /*param_value=*/nullptr, pubkey_data.release(),
                                pubkey_len) ||
        !X509_sign(certs.bad_key_type.get(), key.get(), EVP_sha256())) {
      return Certs{};
    }

    // Sign a copy of the certificate where the key data is unparsable.
    pubkey_data.reset(
        static_cast<uint8_t *>(OPENSSL_memdup(kInvalid, sizeof(kInvalid))));
    certs.bad_key = MakeTestCert(issuer, subject, key.get(), is_ca);
    if (pubkey_data == nullptr || certs.bad_key == nullptr ||
        !X509_PUBKEY_set0_param(X509_get_X509_PUBKEY(certs.bad_key.get()),
                                OBJ_nid2obj(NID_X9_62_id_ecPublicKey),
                                V_ASN1_OBJECT,
                                OBJ_nid2obj(NID_X9_62_prime256v1),
                                pubkey_data.release(), sizeof(kInvalid)) ||
        !X509_sign(certs.bad_key.get(), key.get(), EVP_sha256())) {
      return Certs{};
    }

    UniquePtr<X509_ALGOR> wrong_algo(X509_ALGOR_new());
    if (wrong_algo == nullptr ||
        !X509_ALGOR_set0(wrong_algo.get(), OBJ_nid2obj(NID_subject_alt_name),
                         V_ASN1_NULL, nullptr)) {
      return Certs{};
    }

    certs.bad_sig_type.reset(X509_dup(certs.valid.get()));
    if (certs.bad_sig_type == nullptr ||
        !X509_set1_signature_algo(certs.bad_sig_type.get(), wrong_algo.get())) {
      return Certs{};
    }

    certs.bad_sig.reset(X509_dup(certs.valid.get()));
    if (certs.bad_sig == nullptr ||
        !X509_set1_signature_value(certs.bad_sig.get(), kInvalid,
                                   sizeof(kInvalid))) {
      return Certs{};
    }

    return certs;
  };

  Certs root(make_certs("Root", "Root", /*is_ca=*/true));
  ASSERT_TRUE(root.valid);
  Certs intermediate(make_certs("Root", "Intermediate", /*is_ca=*/true));
  ASSERT_TRUE(intermediate.valid);
  Certs leaf(make_certs("Intermediate", "Leaf", /*is_ca=*/false));
  ASSERT_TRUE(leaf.valid);

  // Check the base chain.
  EXPECT_EQ(X509_V_OK, Verify(leaf.valid.get(), {root.valid.get()},
                              {intermediate.valid.get()}, {}));

  // An invalid or unsupported signature in the leaf or intermediate is noticed.
  EXPECT_EQ(X509_V_ERR_CERT_SIGNATURE_FAILURE,
            Verify(leaf.bad_sig.get(), {root.valid.get()},
                   {intermediate.valid.get()}, {}));
  EXPECT_EQ(X509_V_ERR_CERT_SIGNATURE_FAILURE,
            Verify(leaf.bad_sig_type.get(), {root.valid.get()},
                   {intermediate.valid.get()}, {}));
  EXPECT_EQ(X509_V_ERR_CERT_SIGNATURE_FAILURE,
            Verify(leaf.valid.get(), {root.valid.get()},
                   {intermediate.bad_sig.get()}, {}));
  EXPECT_EQ(X509_V_ERR_CERT_SIGNATURE_FAILURE,
            Verify(leaf.valid.get(), {root.valid.get()},
                   {intermediate.bad_sig_type.get()}, {}));

  // By default, the redundant root signature is not checked.
  EXPECT_EQ(X509_V_OK, Verify(leaf.valid.get(), {root.bad_sig.get()},
                              {intermediate.valid.get()}, {}));
  EXPECT_EQ(X509_V_OK, Verify(leaf.valid.get(), {root.bad_sig_type.get()},
                              {intermediate.valid.get()}, {}));

  // The caller can request checking it, although it's pointless.
  EXPECT_EQ(
      X509_V_ERR_CERT_SIGNATURE_FAILURE,
      Verify(leaf.valid.get(), {root.bad_sig.get()}, {intermediate.valid.get()},
             {}, X509_V_FLAG_CHECK_SS_SIGNATURE));
  EXPECT_EQ(
      X509_V_ERR_CERT_SIGNATURE_FAILURE,
      Verify(leaf.valid.get(), {root.bad_sig_type.get()},
             {intermediate.valid.get()}, {}, X509_V_FLAG_CHECK_SS_SIGNATURE));

  // The above also applies when accepting a trusted, self-signed root as the
  // target certificate.
  EXPECT_EQ(X509_V_OK,
            Verify(root.bad_sig.get(), {root.bad_sig.get()}, {}, {}));
  EXPECT_EQ(X509_V_OK,
            Verify(root.bad_sig_type.get(), {root.bad_sig_type.get()}, {}, {}));
  EXPECT_EQ(X509_V_ERR_CERT_SIGNATURE_FAILURE,
            Verify(root.bad_sig.get(), {root.bad_sig.get()}, {}, {},
                   X509_V_FLAG_CHECK_SS_SIGNATURE));
  EXPECT_EQ(X509_V_ERR_CERT_SIGNATURE_FAILURE,
            Verify(root.bad_sig_type.get(), {root.bad_sig_type.get()}, {}, {},
                   X509_V_FLAG_CHECK_SS_SIGNATURE));

  // If an intermediate is a trust anchor, the redundant signature is always
  // ignored, even with `X509_V_FLAG_CHECK_SS_SIGNATURE`. (We cannot check the
  // signature without the key.)
  EXPECT_EQ(X509_V_OK,
            Verify(leaf.valid.get(), {intermediate.bad_sig.get()}, {}, {},
                   X509_V_FLAG_CHECK_SS_SIGNATURE | X509_V_FLAG_PARTIAL_CHAIN));
  EXPECT_EQ(X509_V_OK,
            Verify(leaf.valid.get(), {intermediate.bad_sig_type.get()}, {}, {},
                   X509_V_FLAG_CHECK_SS_SIGNATURE | X509_V_FLAG_PARTIAL_CHAIN));
  EXPECT_EQ(X509_V_OK, Verify(leaf.valid.get(), {intermediate.bad_sig.get()},
                              {}, {}, X509_V_FLAG_PARTIAL_CHAIN));
  EXPECT_EQ(X509_V_OK,
            Verify(leaf.valid.get(), {intermediate.bad_sig_type.get()}, {}, {},
                   X509_V_FLAG_PARTIAL_CHAIN));

  // Bad keys in the root and intermediate are rejected.
  EXPECT_EQ(X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY,
            Verify(leaf.valid.get(), {root.bad_key.get()},
                   {intermediate.valid.get()}, {}));
  EXPECT_EQ(X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY,
            Verify(leaf.valid.get(), {root.bad_key_type.get()},
                   {intermediate.valid.get()}, {}));
  EXPECT_EQ(X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY,
            Verify(leaf.valid.get(), {root.valid.get()},
                   {intermediate.bad_key.get()}, {}));
  EXPECT_EQ(X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY,
            Verify(leaf.valid.get(), {root.valid.get()},
                   {intermediate.bad_key_type.get()}, {}));

  // Bad keys in the leaf are ignored. The leaf's key is used by the caller.
  EXPECT_EQ(X509_V_OK, Verify(leaf.bad_key.get(), {root.valid.get()},
                              {intermediate.valid.get()}, {}));
  EXPECT_EQ(X509_V_OK, Verify(leaf.bad_key_type.get(), {root.valid.get()},
                              {intermediate.valid.get()}, {}));

  // At the time we go to verify signatures, it is possible that we have a
  // single-element certificate chain with a certificate that isn't self-signed.
  // This does not seem to be reachable except if missing trust anchors are
  // suppressed with the verify callback, but exercise this codepath anyway.
  EXPECT_EQ(X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE,
            Verify(leaf.valid.get(), {}, {}, {}, 0, [](X509_STORE_CTX *ctx) {
              X509_STORE_CTX_set_verify_cb(
                  ctx, [](int ok, X509_STORE_CTX *ctx_inner) -> int {
                    if (ok) {
                      return ok;
                    }
                    // Suppress the missing issuer certificate.
                    int err = X509_STORE_CTX_get_error(ctx_inner);
                    return err == X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY;
                  });
            }));
}

// kConstructedBitString is an X.509 certificate where the signature is encoded
// as a BER constructed BIT STRING. Note that, while OpenSSL's parser accepts
// this input, it interprets the value incorrectly.
static const char kConstructedBitString[] = R"(
-----BEGIN CERTIFICATE-----
MIIBJTCBxqADAgECAgIE0jAKBggqhkjOPQQDAjAPMQ0wCwYDVQQDEwRUZXN0MCAX
DTAwMDEwMTAwMDAwMFoYDzIxMDAwMTAxMDAwMDAwWjAPMQ0wCwYDVQQDEwRUZXN0
MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE5itp4r9ln5e+Lx4NlIpM1Zdrt6ke
DUb73ampHp3culoB59aXqAoY+cPEox5W4nyDSNsWGhz1HX7xlC1Lz3IiwaMQMA4w
DAYDVR0TBAUwAwEB/zAKBggqhkjOPQQDAiNOAyQAMEYCIQCp0iIX5s30KXjihR4g
KnJpd3seqGlVRqCVgrD0KGYDJgA1QAIhAKkx0vR82QU0NtHDD11KX/LuQF2T+2nX
oeKp5LKAbMVi
-----END CERTIFICATE-----
)";

// kConstructedOctetString is an X.509 certificate where an extension is encoded
// as a BER constructed OCTET STRING.
static const char kConstructedOctetString[] = R"(
-----BEGIN CERTIFICATE-----
MIIBJDCByqADAgECAgIE0jAKBggqhkjOPQQDAjAPMQ0wCwYDVQQDEwRUZXN0MCAX
DTAwMDEwMTAwMDAwMFoYDzIxMDAwMTAxMDAwMDAwWjAPMQ0wCwYDVQQDEwRUZXN0
MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE5itp4r9ln5e+Lx4NlIpM1Zdrt6ke
DUb73ampHp3culoB59aXqAoY+cPEox5W4nyDSNsWGhz1HX7xlC1Lz3IiwaMUMBIw
EAYDVR0TJAkEAzADAQQCAf8wCgYIKoZIzj0EAwIDSQAwRgIhAKnSIhfmzfQpeOKF
HiAqcml3ex6oaVVGoJWCsPQoZjVAAiEAqTHS9HzZBTQ20cMPXUpf8u5AXZP7adeh
4qnksoBsxWI=
-----END CERTIFICATE-----
)";

// kIndefiniteLength is an X.509 certificate where the outermost SEQUENCE uses
// BER indefinite-length encoding.
static const char kIndefiniteLength[] = R"(
-----BEGIN CERTIFICATE-----
MIAwgcagAwIBAgICBNIwCgYIKoZIzj0EAwIwDzENMAsGA1UEAxMEVGVzdDAgFw0w
MDAxMDEwMDAwMDBaGA8yMTAwMDEwMTAwMDAwMFowDzENMAsGA1UEAxMEVGVzdDBZ
MBMGByqGSM49AgEGCCqGSM49AwEHA0IABOYraeK/ZZ+Xvi8eDZSKTNWXa7epHg1G
+92pqR6d3LpaAefWl6gKGPnDxKMeVuJ8g0jbFhoc9R1+8ZQtS89yIsGjEDAOMAwG
A1UdEwQFMAMBAf8wCgYIKoZIzj0EAwIDSQAwRgIhAKnSIhfmzfQpeOKFHiAqcml3
ex6oaVVGoJWCsPQoZjVAAiEAqTHS9HzZBTQ20cMPXUpf8u5AXZP7adeh4qnksoBs
xWIAAA==
-----END CERTIFICATE-----
)";

// kNonZeroPadding is an X.09 certificate where the BIT STRING signature field
// has non-zero padding values.
static const char kNonZeroPadding[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

// kHighTagNumber is an X.509 certificate where the outermost SEQUENCE tag uses
// high tag number form.
static const char kHighTagNumber[] = R"(
-----BEGIN CERTIFICATE-----
PxCCASAwgcagAwIBAgICBNIwCgYIKoZIzj0EAwIwDzENMAsGA1UEAxMEVGVzdDAg
Fw0wMDAxMDEwMDAwMDBaGA8yMTAwMDEwMTAwMDAwMFowDzENMAsGA1UEAxMEVGVz
dDBZMBMGByqGSM49AgEGCCqGSM49AwEHA0IABOYraeK/ZZ+Xvi8eDZSKTNWXa7ep
Hg1G+92pqR6d3LpaAefWl6gKGPnDxKMeVuJ8g0jbFhoc9R1+8ZQtS89yIsGjEDAO
MAwGA1UdEwQFMAMBAf8wCgYIKoZIzj0EAwIDSQAwRgIhAKnSIhfmzfQpeOKFHiAq
cml3ex6oaVVGoJWCsPQoZjVAAiEAqTHS9HzZBTQ20cMPXUpf8u5AXZP7adeh4qnk
soBsxWI=
-----END CERTIFICATE-----
)";

// kNonMinimalLengthOuter is an X.509 certificate where the outermost SEQUENCE
// has a non-minimal length.
static const char kNonMinimalLengthOuter[] = R"(
-----BEGIN CERTIFICATE-----
MIMAASAwgcagAwIBAgICBNIwCgYIKoZIzj0EAwIwDzENMAsGA1UEAxMEVGVzdDAg
Fw0wMDAxMDEwMDAwMDBaGA8yMTAwMDEwMTAwMDAwMFowDzENMAsGA1UEAxMEVGVz
dDBZMBMGByqGSM49AgEGCCqGSM49AwEHA0IABOYraeK/ZZ+Xvi8eDZSKTNWXa7ep
Hg1G+92pqR6d3LpaAefWl6gKGPnDxKMeVuJ8g0jbFhoc9R1+8ZQtS89yIsGjEDAO
MAwGA1UdEwQFMAMBAf8wCgYIKoZIzj0EAwIDSQAwRgIhAKnSIhfmzfQpeOKFHiAq
cml3ex6oaVVGoJWCsPQoZjVAAiEAqTHS9HzZBTQ20cMPXUpf8u5AXZP7adeh4qnk
soBsxWI=
-----END CERTIFICATE-----
)";

// kNonMinimalLengthSignature is an X.509 certificate where the signature has a
// non-minimal length.
static const char kNonMinimalLengthSignature[] = R"(
-----BEGIN CERTIFICATE-----
MIIBITCBxqADAgECAgIE0jAKBggqhkjOPQQDAjAPMQ0wCwYDVQQDEwRUZXN0MCAX
DTAwMDEwMTAwMDAwMFoYDzIxMDAwMTAxMDAwMDAwWjAPMQ0wCwYDVQQDEwRUZXN0
MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE5itp4r9ln5e+Lx4NlIpM1Zdrt6ke
DUb73ampHp3culoB59aXqAoY+cPEox5W4nyDSNsWGhz1HX7xlC1Lz3IiwaMQMA4w
DAYDVR0TBAUwAwEB/zAKBggqhkjOPQQDAgOBSQAwRgIhAKnSIhfmzfQpeOKFHiAq
cml3ex6oaVVGoJWCsPQoZjVAAiEAqTHS9HzZBTQ20cMPXUpf8u5AXZP7adeh4qnk
soBsxWI=
-----END CERTIFICATE-----
)";

// kNonMinimalLengthSerial is an X.509 certificate where the serial number has a
// non-minimal length.
static const char kNonMinimalLengthSerial[] = R"(
-----BEGIN CERTIFICATE-----
MIIBITCBx6ADAgECAoECBNIwCgYIKoZIzj0EAwIwDzENMAsGA1UEAxMEVGVzdDAg
Fw0wMDAxMDEwMDAwMDBaGA8yMTAwMDEwMTAwMDAwMFowDzENMAsGA1UEAxMEVGVz
dDBZMBMGByqGSM49AgEGCCqGSM49AwEHA0IABOYraeK/ZZ+Xvi8eDZSKTNWXa7ep
Hg1G+92pqR6d3LpaAefWl6gKGPnDxKMeVuJ8g0jbFhoc9R1+8ZQtS89yIsGjEDAO
MAwGA1UdEwQFMAMBAf8wCgYIKoZIzj0EAwIDSQAwRgIhAKnSIhfmzfQpeOKFHiAq
cml3ex6oaVVGoJWCsPQoZjVAAiEAqTHS9HzZBTQ20cMPXUpf8u5AXZP7adeh4qnk
soBsxWI=
-----END CERTIFICATE-----
)";

TEST(X509Test, BER) {
  // Constructed strings are forbidden in DER.
  EXPECT_FALSE(CertFromPEM(kConstructedBitString));
  EXPECT_FALSE(CertFromPEM(kConstructedOctetString));
  // Indefinite lengths are forbidden in DER.
  EXPECT_FALSE(CertFromPEM(kIndefiniteLength));
  // Padding bits in BIT STRINGs must be zero in BER.
  EXPECT_FALSE(CertFromPEM(kNonZeroPadding));
  // Tags must be minimal in both BER and DER, though many BER decoders
  // incorrectly support non-minimal tags.
  EXPECT_FALSE(CertFromPEM(kHighTagNumber));
  // Lengths must be minimal in DER.
  EXPECT_FALSE(CertFromPEM(kNonMinimalLengthOuter));
  EXPECT_FALSE(CertFromPEM(kNonMinimalLengthSerial));
  // We, for now, accept a non-minimal length in the signature field. See
  // b/18228011.
  EXPECT_TRUE(CertFromPEM(kNonMinimalLengthSignature));
}

TEST(X509Test, Names) {
  UniquePtr<EVP_PKEY> key = PrivateKeyFromPEM(kP256Key);
  ASSERT_TRUE(key);
  UniquePtr<X509> root =
      MakeTestCert("Root", "Root", key.get(), /*is_ca=*/true);
  ASSERT_TRUE(root);
  ASSERT_TRUE(X509_sign(root.get(), key.get(), EVP_sha256()));

  struct {
    std::vector<std::pair<int, std::string>> cert_subject;
    std::vector<std::string> cert_dns_names;
    std::vector<std::string> cert_emails;
    bool cert_invalid_subject_alt_name;
    std::vector<std::string> valid_dns_names;
    std::vector<std::string> invalid_dns_names;
    std::vector<std::string> valid_emails;
    std::vector<std::string> invalid_emails;
    unsigned flags;
  } kTests[] = {
      // DNS names only match DNS names and do so case-insensitively.
      {
          /*cert_subject=*/{},
          /*cert_dns_names=*/{"example.com", "WWW.EXAMPLE.COM"},
          /*cert_emails=*/{},
          /*cert_invalid_subject_alt_name=*/false,
          /*valid_dns_names=*/
          {"example.com", "EXAMPLE.COM", "www.example.com", "WWW.EXAMPLE.COM"},
          /*invalid_dns_names=*/{"test.example.com", "example.org"},
          /*valid_emails=*/{},
          /*invalid_emails=*/{"test@example.com", "example.com"},
          /*flags=*/0,
      },

      // DNS wildcards match exactly one component.
      {
          /*cert_subject=*/{},
          /*cert_dns_names=*/{"*.example.com", "*.EXAMPLE.ORG"},
          /*cert_emails=*/{},
          /*cert_invalid_subject_alt_name=*/false,
          /*valid_dns_names=*/
          {"www.example.com", "WWW.EXAMPLE.COM", "www.example.org",
           "WWW.EXAMPLE.ORG"},
          /*invalid_dns_names=*/{"example.com", "test.www.example.com"},
          /*valid_emails=*/{},
          /*invalid_emails=*/{"test@example.com", "www.example.com"},
          /*flags=*/0,
      },

      // DNS wildcards can be disabled.
      // TODO(davidben): Can we remove this feature? Does anyone use it?
      {
          /*cert_subject=*/{},
          /*cert_dns_names=*/{"example.com", "*.example.com"},
          /*cert_emails=*/{},
          /*cert_invalid_subject_alt_name=*/false,
          /*valid_dns_names=*/{"example.com"},
          /*invalid_dns_names=*/{"www.example.com"},
          /*valid_emails=*/{},
          /*invalid_emails=*/{},
          /*flags=*/X509_CHECK_FLAG_NO_WILDCARDS,
      },

      // Invalid DNS wildcards do not match.
      {
          /*cert_subject=*/{},
          /*cert_dns_names=*/
          {"a.*", "**.b.example", "*c.example", "d*.example", "e*e.example",
           "*", ".", "..", "*."},
          /*cert_emails=*/{},
          /*cert_invalid_subject_alt_name=*/false,
          /*valid_dns_names=*/{},
          /*invalid_dns_names=*/
          {"a.example", "test.b.example", "cc.example", "dd.example",
           "eee.example", "f", "g."},
          /*valid_emails=*/{},
          /*invalid_emails=*/{},
          /*flags=*/0,
      },

      // IDNs match like any other DNS labels.
      {
          /*cert_subject=*/{},
          /*cert_dns_names=*/
          {"xn--rger-koa.a.example", "*.xn--rger-koa.b.example",
           "www.xn--rger-koa.c.example"},
          /*cert_emails=*/{},
          /*cert_invalid_subject_alt_name=*/false,
          /*valid_dns_names=*/
          {"xn--rger-koa.a.example", "www.xn--rger-koa.b.example",
           "www.xn--rger-koa.c.example"},
          /*invalid_dns_names=*/
          {"www.xn--rger-koa.a.example", "xn--rger-koa.b.example",
           "www.xn--rger-koa.d.example"},
          /*valid_emails=*/{},
          /*invalid_emails=*/{},
          /*flags=*/0,
      },

      // For now, DNS names are also extracted out of the common name, but only
      // there is no SAN list.
      // TODO(https://crbug.com/boringssl/464): Remove this.
      {
          /*cert_subject=*/{{NID_commonName, "a.example"},
                            {NID_commonName, "*.b.example"}},
          /*cert_dns_names=*/{},
          /*cert_emails=*/{},
          /*cert_invalid_subject_alt_name=*/false,
          /*valid_dns_names=*/
          {"a.example", "A.EXAMPLE", "test.b.example", "TEST.B.EXAMPLE"},
          /*invalid_dns_names=*/{},
          /*valid_emails=*/{},
          /*invalid_emails=*/{},
          /*flags=*/0,
      },
      {
          /*cert_subject=*/{{NID_commonName, "a.example"},
                            {NID_commonName, "*.b.example"}},
          /*cert_dns_names=*/{"example.com"},
          /*cert_emails=*/{},
          /*cert_invalid_subject_alt_name=*/false,
          /*valid_dns_names=*/{},
          /*invalid_dns_names=*/
          {"a.example", "A.EXAMPLE", "test.b.example", "TEST.B.EXAMPLE"},
          /*valid_emails=*/{},
          /*invalid_emails=*/{},
          /*flags=*/0,
      },

      // An invalid SAN extension should not trigger the common name fallback.
      {
          /*cert_subject=*/{{NID_commonName, "a.example"},
                            {NID_commonName, "*.b.example"}},
          /*cert_dns_names=*/{},
          /*cert_emails=*/{},
          /*cert_invalid_subject_alt_name=*/true,
          /*valid_dns_names=*/{},
          /*invalid_dns_names=*/
          {"a.example", "A.EXAMPLE", "test.b.example", "TEST.B.EXAMPLE"},
          /*valid_emails=*/{},
          /*invalid_emails=*/{},
          /*flags=*/0,
      },

      // Other subject RDNs do not provide DNS names.
      {
          /*cert_subject=*/{{NID_organizationName, "example.com"}},
          /*cert_dns_names=*/{},
          /*cert_emails=*/{},
          /*cert_invalid_subject_alt_name=*/false,
          /*valid_dns_names=*/{},
          /*invalid_dns_names=*/{"example.com"},
          /*valid_emails=*/{},
          /*invalid_emails=*/{},
          /*flags=*/0,
      },

      // Input DNS names cannot have wildcards.
      {
          /*cert_subject=*/{},
          /*cert_dns_names=*/{"www.example.com"},
          /*cert_emails=*/{},
          /*cert_invalid_subject_alt_name=*/false,
          /*valid_dns_names=*/{},
          /*invalid_dns_names=*/{"*.example.com"},
          /*valid_emails=*/{},
          /*invalid_emails=*/{},
          /*flags=*/0,
      },

      // OpenSSL has some non-standard wildcard syntax for input DNS names. We
      // do not support this.
      {
          /*cert_subject=*/{},
          /*cert_dns_names=*/{"www.a.example", "*.b.test"},
          /*cert_emails=*/{},
          /*cert_invalid_subject_alt_name=*/false,
          /*valid_dns_names=*/{},
          /*invalid_dns_names=*/
          {".www.a.example", ".www.b.test", ".a.example", ".b.test", ".example",
           ".test"},
          /*valid_emails=*/{},
          /*invalid_emails=*/{},
          /*flags=*/0,
      },

      // Emails match case-sensitively before the '@' and case-insensitively
      // after. They do not match DNS names.
      {
          /*cert_subject=*/{},
          /*cert_dns_names=*/{},
          /*cert_emails=*/{"test@a.example", "TEST@B.EXAMPLE"},
          /*cert_invalid_subject_alt_name=*/false,
          /*valid_dns_names=*/{},
          /*invalid_dns_names=*/{"a.example", "b.example"},
          /*valid_emails=*/
          {"test@a.example", "test@A.EXAMPLE", "TEST@b.example",
           "TEST@B.EXAMPLE"},
          /*invalid_emails=*/
          {"TEST@a.example", "test@B.EXAMPLE", "another-test@a.example",
           "est@a.example"},
          /*flags=*/0,
      },

      // Emails may also be found in the subject.
      {
          /*cert_subject=*/{{NID_pkcs9_emailAddress, "test@a.example"},
                            {NID_pkcs9_emailAddress, "TEST@B.EXAMPLE"}},
          /*cert_dns_names=*/{},
          /*cert_emails=*/{},
          /*cert_invalid_subject_alt_name=*/false,
          /*valid_dns_names=*/{},
          /*invalid_dns_names=*/{"a.example", "b.example"},
          /*valid_emails=*/
          {"test@a.example", "test@A.EXAMPLE", "TEST@b.example",
           "TEST@B.EXAMPLE"},
          /*invalid_emails=*/
          {"TEST@a.example", "test@B.EXAMPLE", "another-test@a.example",
           "est@a.example"},
          /*flags=*/0,
      },

      // There are no email wildcard names.
      {
          /*cert_subject=*/{},
          /*cert_dns_names=*/{},
          /*cert_emails=*/{"test@*.a.example", "@b.example", "*@c.example"},
          /*cert_invalid_subject_alt_name=*/false,
          /*valid_dns_names=*/{},
          /*invalid_dns_names=*/{},
          /*valid_emails=*/{},
          /*invalid_emails=*/
          {"test@test.a.example", "test@b.example", "test@c.example"},
          /*flags=*/0,
      },

      // Unrelated RDNs can be skipped when looking in the subject.
      {
          /*cert_subject=*/{{NID_organizationName, "Acme Corporation"},
                            {NID_commonName, "a.example"},
                            {NID_pkcs9_emailAddress, "test@b.example"},
                            {NID_countryName, "US"}},
          /*cert_dns_names=*/{},
          /*cert_emails=*/{},
          /*cert_invalid_subject_alt_name=*/false,
          /*valid_dns_names=*/{"a.example"},
          /*invalid_dns_names=*/{},
          /*valid_emails=*/{"test@b.example"},
          /*invalid_emails=*/{},
          /*flags=*/0,
      },
  };

  size_t i = 0;
  for (const auto &t : kTests) {
    SCOPED_TRACE(i++);

    // Issue a test certificate.
    UniquePtr<X509> cert =
        MakeTestCert("Root", "Leaf", key.get(), /*is_ca=*/false);
    ASSERT_TRUE(cert);
    if (!t.cert_subject.empty()) {
      UniquePtr<X509_NAME> subject(X509_NAME_new());
      ASSERT_TRUE(subject);
      for (const auto &entry : t.cert_subject) {
        ASSERT_TRUE(X509_NAME_add_entry_by_NID(
            subject.get(), entry.first, MBSTRING_ASC,
            reinterpret_cast<const unsigned char *>(entry.second.data()),
            entry.second.size(), /*loc=*/-1, /*set=*/0));
      }
      ASSERT_TRUE(X509_set_subject_name(cert.get(), subject.get()));
    }
    UniquePtr<GENERAL_NAMES> sans(sk_GENERAL_NAME_new_null());
    ASSERT_TRUE(sans);
    for (const auto &dns : t.cert_dns_names) {
      UniquePtr<GENERAL_NAME> name(GENERAL_NAME_new());
      ASSERT_TRUE(name);
      name->type = GEN_DNS;
      name->d.dNSName = ASN1_IA5STRING_new();
      ASSERT_TRUE(name->d.dNSName);
      ASSERT_TRUE(ASN1_STRING_set(name->d.dNSName, dns.data(), dns.size()));
      ASSERT_TRUE(PushToStack(sans.get(), std::move(name)));
    }
    for (const auto &email : t.cert_emails) {
      UniquePtr<GENERAL_NAME> name(GENERAL_NAME_new());
      ASSERT_TRUE(name);
      name->type = GEN_EMAIL;
      name->d.rfc822Name = ASN1_IA5STRING_new();
      ASSERT_TRUE(name->d.rfc822Name);
      ASSERT_TRUE(
          ASN1_STRING_set(name->d.rfc822Name, email.data(), email.size()));
      ASSERT_TRUE(PushToStack(sans.get(), std::move(name)));
    }
    if (t.cert_invalid_subject_alt_name) {
      UniquePtr<X509_EXTENSION> ext(X509_EXTENSION_new());
      ASSERT_TRUE(ext);
      ASSERT_TRUE(X509_EXTENSION_set_object(ext.get(),
                                            OBJ_nid2obj(NID_subject_alt_name)));
      // Leave the contents as an empty string, which is invalid.
      ASSERT_TRUE(X509_add_ext(cert.get(), ext.get(), -1));
    } else if (sk_GENERAL_NAME_num(sans.get()) != 0) {
      ASSERT_TRUE(X509_add1_ext_i2d(cert.get(), NID_subject_alt_name,
                                    sans.get(), /*crit=*/0, /*flags=*/0));
    }
    ASSERT_TRUE(X509_sign(cert.get(), key.get(), EVP_sha256()));

    for (const auto &dns : t.valid_dns_names) {
      SCOPED_TRACE(dns);
      EXPECT_EQ(1, X509_check_host(cert.get(), dns.data(), dns.size(), t.flags,
                                   /*peername=*/nullptr));
      EXPECT_EQ(t.cert_invalid_subject_alt_name ? X509_V_ERR_INVALID_EXTENSION
                                                : X509_V_OK,
                Verify(cert.get(), {root.get()}, /*intermediates=*/{},
                       /*crls=*/{}, /*flags=*/0, [&](X509_STORE_CTX *ctx) {
                         X509_VERIFY_PARAM *param =
                             X509_STORE_CTX_get0_param(ctx);
                         ASSERT_TRUE(X509_VERIFY_PARAM_set1_host(
                             param, dns.data(), dns.size()));
                         X509_VERIFY_PARAM_set_hostflags(param, t.flags);
                       }));
    }

    for (const auto &dns : t.invalid_dns_names) {
      SCOPED_TRACE(dns);
      EXPECT_EQ(0, X509_check_host(cert.get(), dns.data(), dns.size(), t.flags,
                                   /*peername=*/nullptr));
      if (t.cert_invalid_subject_alt_name) {
        EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_ASN1, ASN1_R_DECODE_ERROR}}));
      }
      EXPECT_EQ(t.cert_invalid_subject_alt_name ? X509_V_ERR_INVALID_EXTENSION
                                                : X509_V_ERR_HOSTNAME_MISMATCH,
                Verify(cert.get(), {root.get()}, /*intermediates=*/{},
                       /*crls=*/{}, /*flags=*/0, [&](X509_STORE_CTX *ctx) {
                         X509_VERIFY_PARAM *param =
                             X509_STORE_CTX_get0_param(ctx);
                         ASSERT_TRUE(X509_VERIFY_PARAM_set1_host(
                             param, dns.data(), dns.size()));
                         X509_VERIFY_PARAM_set_hostflags(param, t.flags);
                       }));
    }

    for (const auto &email : t.valid_emails) {
      SCOPED_TRACE(email);
      EXPECT_EQ(
          1, X509_check_email(cert.get(), email.data(), email.size(), t.flags));
      EXPECT_EQ(t.cert_invalid_subject_alt_name ? X509_V_ERR_INVALID_EXTENSION
                                                : X509_V_OK,
                Verify(cert.get(), {root.get()}, /*intermediates=*/{},
                       /*crls=*/{}, /*flags=*/0, [&](X509_STORE_CTX *ctx) {
                         X509_VERIFY_PARAM *param =
                             X509_STORE_CTX_get0_param(ctx);
                         ASSERT_TRUE(X509_VERIFY_PARAM_set1_email(
                             param, email.data(), email.size()));
                         X509_VERIFY_PARAM_set_hostflags(param, t.flags);
                       }));
    }

    for (const auto &email : t.invalid_emails) {
      SCOPED_TRACE(email);
      EXPECT_EQ(
          0, X509_check_email(cert.get(), email.data(), email.size(), t.flags));
      EXPECT_EQ(t.cert_invalid_subject_alt_name ? X509_V_ERR_INVALID_EXTENSION
                                                : X509_V_ERR_EMAIL_MISMATCH,
                Verify(cert.get(), {root.get()}, /*intermediates=*/{},
                       /*crls=*/{}, /*flags=*/0, [&](X509_STORE_CTX *ctx) {
                         X509_VERIFY_PARAM *param =
                             X509_STORE_CTX_get0_param(ctx);
                         ASSERT_TRUE(X509_VERIFY_PARAM_set1_email(
                             param, email.data(), email.size()));
                         X509_VERIFY_PARAM_set_hostflags(param, t.flags);
                       }));
    }
  }
}

// Adding an invalid entry to an `X509_NAME` should not be possible.
TEST(X509Test, AddInvalidEntryToName) {
  UniquePtr<X509_NAME> name(X509_NAME_new());
  ASSERT_TRUE(name);
  UniquePtr<X509_NAME_ENTRY> entry(X509_NAME_ENTRY_new());
  ASSERT_TRUE(entry);
  EXPECT_FALSE(
      X509_NAME_add_entry(name.get(), entry.get(), /*loc=*/-1, /*set=*/0));
}

TEST(X509Test, AddDuplicates) {
  UniquePtr<X509_STORE> store(X509_STORE_new());
  UniquePtr<X509> a(CertFromPEM(kCrossSigningRootPEM));
  UniquePtr<X509> b(CertFromPEM(kRootCAPEM));

  ASSERT_TRUE(store);
  ASSERT_TRUE(a);
  ASSERT_TRUE(b);

  EXPECT_TRUE(X509_STORE_add_cert(store.get(), a.get()));
  EXPECT_TRUE(X509_STORE_add_cert(store.get(), b.get()));
  EXPECT_TRUE(X509_STORE_add_cert(store.get(), a.get()));
  EXPECT_TRUE(X509_STORE_add_cert(store.get(), b.get()));
  EXPECT_TRUE(X509_STORE_add_cert(store.get(), a.get()));
  EXPECT_TRUE(X509_STORE_add_cert(store.get(), b.get()));

  EXPECT_EQ(sk_X509_OBJECT_num(X509_STORE_get0_objects(store.get())), 2u);
}

TEST(X509Test, BytesToHex) {
  struct {
    std::vector<uint8_t> bytes;
    const char *hex;
  } kTests[] = {
      {{}, ""},
      {{0x00}, "00"},
      {{0x00, 0x11, 0x22}, "00:11:22"},
      {{0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef},
       "01:23:45:67:89:AB:CD:EF"},
  };
  for (const auto &t : kTests) {
    SCOPED_TRACE(Bytes(t.bytes));
    UniquePtr<char> hex(x509v3_bytes_to_hex(t.bytes.data(), t.bytes.size()));
    ASSERT_TRUE(hex);
    EXPECT_STREQ(hex.get(), t.hex);
  }
}

TEST(X509Test, NamePrint) {
  // Registering one of the test OIDs as a nameless OID should not impact
  // printing. Note this impacts global state.
  ASSERT_NE(OBJ_create("1.2.840.113554.4.1.72585.3", nullptr, nullptr),
            NID_undef);

  // kTestName is a DER-encoded X.509 that covers many cases.
  //
  // SEQUENCE {
  //   SET {
  //     SEQUENCE {
  //       # countryName
  //       OBJECT_IDENTIFIER { 2.5.4.6 }
  //       PrintableString { "US" }
  //     }
  //   }
  //   # Sets may be multi-valued, with different attributes. Try to keep this
  //   # in DER set order, in case we ever enforce this in the parser.
  //   SET {
  //     SEQUENCE {
  //       # stateOrProvinceName
  //       OBJECT_IDENTIFIER { 2.5.4.8 }
  //       PrintableString { "Some State" }
  //     }
  //     SEQUENCE {
  //       # stateOrProvinceName
  //       OBJECT_IDENTIFIER { 2.5.4.8 }
  //       UTF8String { "Some Other State \xe2\x98\x83" }
  //     }
  //     SEQUENCE {
  //       # stateOrProvinceName
  //       OBJECT_IDENTIFIER { 2.5.4.8 }
  //       BMPString { u"Another State \u2603" }
  //     }
  //     SEQUENCE {
  //       # A custom OID
  //       OBJECT_IDENTIFIER { 1.2.840.113554.4.1.72585.2 }
  //       UniversalString { U"\u2603" }
  //     }
  //   }
  //   # Custom OIDs may have non-string values.
  //   SET {
  //     SEQUENCE {
  //       OBJECT_IDENTIFIER { 1.2.840.113554.4.1.72585.3 }
  //       SEQUENCE { INTEGER { 1 } INTEGER { 2 } }
  //     }
  //   }
  //   SET {
  //     SEQUENCE {
  //       # organizationName
  //       OBJECT_IDENTIFIER { 2.5.4.10 }
  //       PrintableString { "Org Name" }
  //     }
  //   }
  //   SET {
  //     SEQUENCE {
  //       # commonName
  //       OBJECT_IDENTIFIER { 2.5.4.3 }
  //       # Embed common delimiter forms to test how well they get escaped.
  //       UTF8String { "Common
  //       Name/CN=A/CN=B,CN=A,CN=B+CN=A+CN=B;CN=A;CN=B\nCN=A\n" }
  //     }
  //   }
  //   SET {
  //   SEQUENCE {
  //     # commonName
  //     OBJECT_IDENTIFIER { 2.5.4.3 }
  //     # Test escaping of leading and trailing spaces.
  //     UTF8String { " spaces " }
  //   }
  // }
  static const uint8_t kTestName[] = {
      0x30, 0x82, 0x01, 0x00, 0x31, 0x0b, 0x30, 0x09, 0x06, 0x03, 0x55, 0x04,
      0x06, 0x13, 0x02, 0x55, 0x53, 0x31, 0x6d, 0x30, 0x11, 0x06, 0x03, 0x55,
      0x04, 0x08, 0x13, 0x0a, 0x53, 0x6f, 0x6d, 0x65, 0x20, 0x53, 0x74, 0x61,
      0x74, 0x65, 0x30, 0x1b, 0x06, 0x03, 0x55, 0x04, 0x08, 0x0c, 0x14, 0x53,
      0x6f, 0x6d, 0x65, 0x20, 0x4f, 0x74, 0x68, 0x65, 0x72, 0x20, 0x53, 0x74,
      0x61, 0x74, 0x65, 0x20, 0xe2, 0x98, 0x83, 0x30, 0x25, 0x06, 0x03, 0x55,
      0x04, 0x08, 0x1e, 0x1e, 0x00, 0x41, 0x00, 0x6e, 0x00, 0x6f, 0x00, 0x74,
      0x00, 0x68, 0x00, 0x65, 0x00, 0x72, 0x00, 0x20, 0x00, 0x53, 0x00, 0x74,
      0x00, 0x61, 0x00, 0x74, 0x00, 0x65, 0x00, 0x20, 0x26, 0x03, 0x30, 0x14,
      0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04, 0x01, 0x84, 0xb7,
      0x09, 0x02, 0x1c, 0x04, 0x00, 0x00, 0x26, 0x03, 0x31, 0x18, 0x30, 0x16,
      0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04, 0x01, 0x84, 0xb7,
      0x09, 0x03, 0x30, 0x06, 0x02, 0x01, 0x01, 0x02, 0x01, 0x02, 0x31, 0x11,
      0x30, 0x0f, 0x06, 0x03, 0x55, 0x04, 0x0a, 0x13, 0x08, 0x4f, 0x72, 0x67,
      0x20, 0x4e, 0x61, 0x6d, 0x65, 0x31, 0x42, 0x30, 0x40, 0x06, 0x03, 0x55,
      0x04, 0x03, 0x0c, 0x39, 0x43, 0x6f, 0x6d, 0x6d, 0x6f, 0x6e, 0x20, 0x4e,
      0x61, 0x6d, 0x65, 0x2f, 0x43, 0x4e, 0x3d, 0x41, 0x2f, 0x43, 0x4e, 0x3d,
      0x42, 0x2c, 0x43, 0x4e, 0x3d, 0x41, 0x2c, 0x43, 0x4e, 0x3d, 0x42, 0x2b,
      0x43, 0x4e, 0x3d, 0x41, 0x2b, 0x43, 0x4e, 0x3d, 0x42, 0x3b, 0x43, 0x4e,
      0x3d, 0x41, 0x3b, 0x43, 0x4e, 0x3d, 0x42, 0x0a, 0x43, 0x4e, 0x3d, 0x41,
      0x0a, 0x31, 0x11, 0x30, 0x0f, 0x06, 0x03, 0x55, 0x04, 0x03, 0x0c, 0x08,
      0x20, 0x73, 0x70, 0x61, 0x63, 0x65, 0x73, 0x20};

  const uint8_t *ptr = kTestName;
  UniquePtr<X509_NAME> name(d2i_X509_NAME(nullptr, &ptr, sizeof(kTestName)));
  ASSERT_TRUE(name);
  EXPECT_EQ(ptr, kTestName + sizeof(kTestName));

  struct {
    int indent;
    unsigned long flags;
    std::string printed;
  } kTests[] = {
      // RFC 2253 uses , and + separators and encodes the RDNs in reverse.
      // OpenSSL's implementation additionally happens to reverse the values
      // within each RDN. RFC 2253 says any order is permissible.
      {/*indent=*/0,
       /*flags=*/XN_FLAG_RFC2253,
       "CN=\\ spaces\\ ,"
       "CN=Common "
       "Name/CN=A/CN=B\\,CN=A\\,CN=B\\+CN=A\\+CN=B\\;CN=A\\;CN=B\\0ACN=A\\0A,"
       "O=Org Name,"
       "1.2.840.113554.4.1.72585.3=#3006020101020102,"
       "1.2.840.113554.4.1.72585.2=#1C0400002603+"
       "ST=Another State \\E2\\98\\83+"
       "ST=Some Other State \\E2\\98\\83+"
       "ST=Some State,"
       "C=US"},
      {/*indent=*/2,
       /*flags=*/XN_FLAG_RFC2253,
       "  "
       "CN=\\ spaces\\ ,"
       "CN=Common "
       "Name/CN=A/CN=B\\,CN=A\\,CN=B\\+CN=A\\+CN=B\\;CN=A\\;CN=B\\0ACN=A\\0A,"
       "O=Org Name,"
       "1.2.840.113554.4.1.72585.3=#3006020101020102,"
       "1.2.840.113554.4.1.72585.2=#1C0400002603+"
       "ST=Another State \\E2\\98\\83+"
       "ST=Some Other State \\E2\\98\\83+"
       "ST=Some State,"
       "C=US"},
      // `XN_FLAG_ONELINE` is an OpenSSL-specific single-line format. It also
      // omits `XN_FLAG_DUMP_UNKNOWN_FIELDS`, so unknown OIDs that use known
      // string types will still be decoded. (This may drop important
      // information if the unknown OID distinguishes between string types.) It
      // also passes `ASN1_STRFLGS_ESC_QUOTE`.
      {/*indent=*/0,
       /*flags=*/XN_FLAG_ONELINE,
       "C = US, "
       "ST = Some State + "
       "ST = Some Other State \\E2\\98\\83 + "
       "ST = Another State \\E2\\98\\83 + "
       "1.2.840.113554.4.1.72585.2 = \\E2\\98\\83, "
       "1.2.840.113554.4.1.72585.3 = #3006020101020102, "
       "O = Org Name, "
       "CN = \"Common "
       "Name/CN=A/CN=B,CN=A,CN=B+CN=A+CN=B;CN=A;CN=B\\0ACN=A\\0A\", "
       "CN = \" spaces \""},
      // Callers can also customize the output, with both `XN_FLAG_*` and
      // `ASN1_STRFLGS_*`. `XN_FLAG_SEP_SPLUS_SPC` uses semicolon separators.
      {/*indent=*/0,
       /*flags=*/XN_FLAG_SEP_SPLUS_SPC | ASN1_STRFLGS_RFC2253 |
           ASN1_STRFLGS_ESC_QUOTE,
       "C=US; "
       "ST=Some State + "
       "ST=Some Other State \\E2\\98\\83 + "
       "ST=Another State \\E2\\98\\83 + "
       "1.2.840.113554.4.1.72585.2=\\E2\\98\\83; "
       "1.2.840.113554.4.1.72585.3=#3006020101020102; "
       "O=Org Name; "
       "CN=\"Common "
       "Name/CN=A/CN=B,CN=A,CN=B+CN=A+CN=B;CN=A;CN=B\\0ACN=A\\0A\"; "
       "CN=\" spaces \""},
      // Node uses these parameters.
      {/*indent=*/0,
       /*flags=*/ASN1_STRFLGS_ESC_2253 | ASN1_STRFLGS_ESC_CTRL |
           ASN1_STRFLGS_UTF8_CONVERT | XN_FLAG_SEP_MULTILINE | XN_FLAG_FN_SN,
       "C=US\n"
       "ST=Some State + "
       "ST=Some Other State \xE2\x98\x83 + "
       "ST=Another State \xE2\x98\x83 + "
       "1.2.840.113554.4.1.72585.2=\xE2\x98\x83\n"
       "1.2.840.113554.4.1.72585.3=0\\06\\02\\01\\01\\02\\01\\02\n"
       "O=Org Name\n"
       "CN=Common "
       "Name/CN=A/CN=B\\,CN=A\\,CN=B\\+CN=A\\+CN=B\\;CN=A\\;CN=B\\0ACN=A\\0A\n"
       "CN=\\ spaces\\ "},
      // `XN_FLAG_COMPAT` matches `X509_NAME_print`, rather than
      // `X509_NAME_print_ex`.
      //
      // TODO(davidben): This works by post-processing the output of
      // `X509_NAME_oneline`, which uses "/"" separators, and replacing with
      // ", ". The escaping is ambiguous and the post-processing is buggy, so
      // some of the trailing slashes are still present and some internal
      // slashes are mis-converted.
      {/*indent=*/0,
       /*flags=*/XN_FLAG_COMPAT,
       "C=US, "
       "ST=Some State, "
       "ST=Some Other State \\xE2\\x98\\x83, "
       "ST=\\x00A\\x00n\\x00o\\x00t\\x00h\\x00e\\x00r\\x00 "
       "\\x00S\\x00t\\x00a\\x00t\\x00e\\x00 &\\x03/"
       "1.2.840.113554.4.1.72585.2=\\x00\\x00&\\x03/"
       "1.2.840.113554.4.1.72585.3=0\\x06\\x02\\x01\\x01\\x02\\x01\\x02, "
       "O=Org Name, "
       "CN=Common Name, "
       "CN=A, CN=B,CN=A,CN=B+CN=A+CN=B;CN=A;CN=B\\x0ACN=A\\x0A, "
       "CN= spaces "},
  };
  for (const auto &t : kTests) {
    SCOPED_TRACE(t.printed);
    UniquePtr<BIO> bio(BIO_new(BIO_s_mem()));
    ASSERT_TRUE(bio);
    int len = X509_NAME_print_ex(bio.get(), name.get(), t.indent, t.flags);
    ASSERT_GT(len, 0);

    const uint8_t *printed;
    size_t printed_len;
    ASSERT_TRUE(BIO_mem_contents(bio.get(), &printed, &printed_len));
    EXPECT_EQ(std::string(printed, printed + printed_len), t.printed);
    if (t.flags != XN_FLAG_COMPAT) {
      // TODO(davidben): `XN_FLAG_COMPAT` does not return the length.
      EXPECT_EQ(static_cast<size_t>(len), printed_len);

      // Passing a null `BIO` measures the output instead.
      len = X509_NAME_print_ex(nullptr, name.get(), t.indent, t.flags);
      EXPECT_GT(len, 0);
      EXPECT_EQ(static_cast<size_t>(len), printed_len);
    }
  }

  // TODO(davidben): This escapes the underlying bytes in the string, but that
  // is ambiguous without capturing the type. Should this escape like
  // `ASN1_STRFLGS_UTF8_CONVERT` instead?
  static const char *kOnelineComponents[] = {
      "/C=US",
      "/ST=Some State",
      "/ST=Some Other State \\xE2\\x98\\x83",
      ("/ST=\\x00A\\x00n\\x00o\\x00t\\x00h\\x00e\\x00r\\x00 "
       "\\x00S\\x00t\\x00a\\x00t\\x00e\\x00 &\\x03"),
      "/1.2.840.113554.4.1.72585.2=\\x00\\x00&\\x03",
      "/1.2.840.113554.4.1.72585.3=0\\x06\\x02\\x01\\x01\\x02\\x01\\x02",
      "/O=Org Name",
      "/CN=Common Name/CN=A/CN=B,CN=A,CN=B+CN=A+CN=B;CN=A;CN=B\\x0ACN=A\\x0A",
      "/CN= spaces ",
  };
  std::string oneline_expected;
  for (const auto &component : kOnelineComponents) {
    oneline_expected += component;
  }

  // Given null buffer, `X509_NAME_oneline` allocates a new output.
  UniquePtr<char> oneline(X509_NAME_oneline(name.get(), nullptr, 0));
  ASSERT_TRUE(oneline);
  EXPECT_EQ(oneline.get(), oneline_expected);

  // Otherwise it writes to the specified buffer. Note one extra byte is needed
  // for the trailing NUL.
  char buf[1024];
  ASSERT_GE(sizeof(buf), oneline_expected.size() + 2);
  ASSERT_EQ(buf,
            X509_NAME_oneline(name.get(), buf, oneline_expected.size() + 1));
  EXPECT_EQ(buf, oneline_expected);

  memset(buf, 'a', sizeof(buf));
  ASSERT_EQ(buf,
            X509_NAME_oneline(name.get(), buf, oneline_expected.size() + 2));
  EXPECT_EQ(buf, oneline_expected);

  // If the length is too small, `X509_NAME_oneline` truncates at name
  // entry boundaries.
  EXPECT_EQ(nullptr, X509_NAME_oneline(name.get(), buf, 0));
  for (size_t len = 1; len < oneline_expected.size(); len++) {
    SCOPED_TRACE(len);
    memset(buf, 'a', sizeof(buf));
    EXPECT_EQ(buf, X509_NAME_oneline(name.get(), buf, len));

    std::string truncated;
    for (const auto &component : kOnelineComponents) {
      if (truncated.size() + strlen(component) + 1 > len) {
        break;
      }
      truncated += component;
    }
    EXPECT_EQ(buf, truncated);
  }
}

// kLargeSerialPEM is a certificate with a large serial number.
static const char kLargeSerialPEM[] = R"(
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
)";

TEST(X509Test, Print) {
  UniquePtr<X509> cert(CertFromPEM(kLargeSerialPEM));
  ASSERT_TRUE(cert);

  UniquePtr<BIO> bio(BIO_new(BIO_s_mem()));
  ASSERT_TRUE(bio);
  EXPECT_TRUE(X509_print_ex(bio.get(), cert.get(), 0, 0));
  // Nothing should be left in the error queue.
  EXPECT_EQ(0u, ERR_peek_error());

  // This output is not guaranteed to be stable, but we assert on it to make
  // sure something is printed.
  const uint8_t *data;
  size_t data_len;
  ASSERT_TRUE(BIO_mem_contents(bio.get(), &data, &data_len));
  auto print = BytesAsStringView(Span(data, data_len));
  EXPECT_EQ(print, R"(Certificate:
    Data:
        Version: 3 (0x2)
        Serial Number:
            01:23:45:67:89:ab:cd:ef:01:23:45:67:89:ab:cd:ef
    Signature Algorithm: sha256WithRSAEncryption
        Issuer: O=BoringSSL TESTING, CN=Intermediate CA
        Validity
            Not Before: Jan  1 00:00:00 2015 GMT
            Not After : Jan  1 00:00:00 2100 GMT
        Subject: O=BoringSSL TESTING, CN=example.com
        Subject Public Key Info:
            Public Key Algorithm: rsaEncryption
                Public-Key: (1024 bit)
                Modulus:
                    00:c3:d1:4d:19:62:0a:92:84:9e:e8:3a:3b:32:34:
                    ac:95:5c:41:ea:79:a7:e6:93:f6:c0:a0:fa:98:fe:
                    1d:5c:a0:fc:36:13:c2:a6:7a:a8:94:4a:84:cf:8c:
                    6e:48:5d:26:e5:3b:17:2a:a5:b0:17:82:78:cf:ce:
                    8f:03:23:71:8d:32:10:1f:f1:26:0d:62:ca:07:ee:
                    07:3b:53:2e:e3:e7:1f:1b:52:b8:ac:1a:7b:93:1e:
                    a9:2a:1f:a7:78:fd:ee:c4:4c:9e:e2:dc:2a:51:f1:
                    bb:ca:d7:a0:e0:80:4b:d0:4e:e7:4b:8a:9c:fc:14:
                    11:ed:62:11:5a:91:f7:61:4f
                Exponent: 65537 (0x10001)
        X509v3 extensions:
            X509v3 Key Usage: critical
                Digital Signature, Key Encipherment
            X509v3 Extended Key Usage:
                TLS Web Server Authentication, TLS Web Client Authentication
            X509v3 Basic Constraints: critical
                CA:FALSE
            X509v3 Subject Key Identifier:
                A3:79:A6:F6:EE:AF:B9:A5:5E:37:8C:11:80:34:E2:75
            X509v3 Authority Key Identifier:
                keyid:8C:1A:68:A8:B5:76:DB:5D:57:7B:1F:8D:14:B2:06:A3

    Signature Algorithm: sha256WithRSAEncryption
         63:fe:9f:89:0a:1a:7f:fc:b9:d7:58:2d:64:d7:6d:4b:33:f8:
         a2:ee:11:73:43:33:2b:b7:bd:1b:9f:2e:34:e9:21:b3:f6:30:
         23:68:f3:97:e1:2d:e0:b7:7f:32:ae:18:e9:3e:e9:01:95:2c:
         e0:41:71:60:eb:ac:ba:ab:9a:a9:d6:74:13:0f:50:b0:e8:d9:
         0a:05:ef:56:b8:19:58:de:26:1f:9a:c7:fb:59:3f:27:86:54:
         f5:0a:db:54:c4:d0:b0:c8:c5:fd:9a:d7:57:75:08:9c:39:f3:
         63:20:65:02:0f:93:8b:57:93:e0:1c:53:d1:2a:21:c7:8a:80:
         40:86
)");
}

TEST(X509Test, AddExt) {
  UniquePtr<X509> x509(X509_new());
  ASSERT_TRUE(x509);

  struct Extension {
    int nid;
    bool critical;
    std::vector<uint8_t> data;
  };
  auto expect_extensions = [&](const std::vector<Extension> &exts) {
    ASSERT_EQ(static_cast<size_t>(X509_get_ext_count(x509.get())), exts.size());
    for (size_t i = 0; i < exts.size(); i++) {
      SCOPED_TRACE(i);
      const X509_EXTENSION *ext = X509_get_ext(x509.get(), static_cast<int>(i));
      EXPECT_EQ(OBJ_obj2nid(X509_EXTENSION_get_object(ext)), exts[i].nid);
      EXPECT_EQ(X509_EXTENSION_get_critical(ext), exts[i].critical ? 1 : 0);
      const ASN1_OCTET_STRING *data = X509_EXTENSION_get_data(ext);
      EXPECT_EQ(Bytes(ASN1StringAsBytes(data)), Bytes(exts[i].data));
    }
  };

  // Make a few sample extensions.

  // SEQUENCE {}
  std::vector<uint8_t> basic1_der = {0x30, 0x00};
  const uint8_t *inp = basic1_der.data();
  UniquePtr<BASIC_CONSTRAINTS> basic1_obj(
      d2i_BASIC_CONSTRAINTS(nullptr, &inp, basic1_der.size()));
  EXPECT_EQ(inp, basic1_der.data() + basic1_der.size());

  // SEQUENCE { BOOLEAN { TRUE } }
  std::vector<uint8_t> basic2_der = {0x30, 0x03, 0x01, 0x01, 0xff};
  inp = basic2_der.data();
  UniquePtr<BASIC_CONSTRAINTS> basic2_obj(
      d2i_BASIC_CONSTRAINTS(nullptr, &inp, basic2_der.size()));
  EXPECT_EQ(inp, basic2_der.data() + basic2_der.size());

  // OCTET_STRING {}
  std::vector<uint8_t> skid1_der = {0x04, 0x00};
  inp = skid1_der.data();
  UniquePtr<ASN1_OCTET_STRING> skid1_obj(
      d2i_ASN1_OCTET_STRING(nullptr, &inp, skid1_der.size()));
  EXPECT_EQ(inp, skid1_der.data() + skid1_der.size());

  // OCTET_STRING { "a" }
  std::vector<uint8_t> skid2_der = {0x04, 0x01, 0x61};
  inp = skid2_der.data();
  UniquePtr<ASN1_OCTET_STRING> skid2_obj(
      d2i_ASN1_OCTET_STRING(nullptr, &inp, skid2_der.size()));
  EXPECT_EQ(inp, skid2_der.data() + skid2_der.size());

  // Initially, the extension list is empty.
  expect_extensions({});

  // Adding extensions works with the default settings.
  EXPECT_EQ(
      1, X509_add1_ext_i2d(x509.get(), NID_basic_constraints, basic1_obj.get(),
                           /*crit=*/1, X509V3_ADD_DEFAULT));
  expect_extensions({{NID_basic_constraints, true, basic1_der}});
  EXPECT_EQ(1, X509_add1_ext_i2d(x509.get(), NID_subject_key_identifier,
                                 skid1_obj.get(),
                                 /*crit=*/0, X509V3_ADD_DEFAULT));
  expect_extensions({{NID_basic_constraints, true, basic1_der},
                     {NID_subject_key_identifier, false, skid1_der}});

  // By default, we cannot add duplicates.
  EXPECT_EQ(
      0, X509_add1_ext_i2d(x509.get(), NID_basic_constraints, basic2_obj.get(),
                           /*crit=*/0, X509V3_ADD_DEFAULT));
  EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_X509V3, X509V3_R_EXTENSION_EXISTS}}));
  expect_extensions({{NID_basic_constraints, true, basic1_der},
                     {NID_subject_key_identifier, false, skid1_der}});

  // `X509V3_ADD_KEEP_EXISTING` silently keeps the existing extension if already
  // present.
  EXPECT_EQ(
      1, X509_add1_ext_i2d(x509.get(), NID_basic_constraints, basic2_obj.get(),
                           /*crit=*/0, X509V3_ADD_KEEP_EXISTING));
  expect_extensions({{NID_basic_constraints, true, basic1_der},
                     {NID_subject_key_identifier, false, skid1_der}});

  // `X509V3_ADD_REPLACE` replaces it.
  EXPECT_EQ(
      1, X509_add1_ext_i2d(x509.get(), NID_basic_constraints, basic2_obj.get(),
                           /*crit=*/0, X509V3_ADD_REPLACE));
  expect_extensions({{NID_basic_constraints, false, basic2_der},
                     {NID_subject_key_identifier, false, skid1_der}});

  // `X509V3_ADD_REPLACE_EXISTING` also replaces matches.
  EXPECT_EQ(1, X509_add1_ext_i2d(x509.get(), NID_subject_key_identifier,
                                 skid2_obj.get(),
                                 /*crit=*/1, X509V3_ADD_REPLACE_EXISTING));
  expect_extensions({{NID_basic_constraints, false, basic2_der},
                     {NID_subject_key_identifier, true, skid2_der}});

  // `X509V3_ADD_DELETE` ignores the value and deletes the extension.
  EXPECT_EQ(1, X509_add1_ext_i2d(x509.get(), NID_basic_constraints, nullptr, 0,
                                 X509V3_ADD_DELETE));
  expect_extensions({{NID_subject_key_identifier, true, skid2_der}});

  // Not finding an extension to delete is an error.
  EXPECT_EQ(0, X509_add1_ext_i2d(x509.get(), NID_basic_constraints, nullptr, 0,
                                 X509V3_ADD_DELETE));
  EXPECT_TRUE(
      ErrorsAreAndClear({{ERR_LIB_X509V3, X509V3_R_EXTENSION_NOT_FOUND}}));
  expect_extensions({{NID_subject_key_identifier, true, skid2_der}});

  // `X509V3_ADD_REPLACE_EXISTING` fails if it cannot find a match.
  EXPECT_EQ(
      0, X509_add1_ext_i2d(x509.get(), NID_basic_constraints, basic1_obj.get(),
                           /*crit=*/1, X509V3_ADD_REPLACE_EXISTING));
  EXPECT_TRUE(
      ErrorsAreAndClear({{ERR_LIB_X509V3, X509V3_R_EXTENSION_NOT_FOUND}}));
  expect_extensions({{NID_subject_key_identifier, true, skid2_der}});

  // `X509V3_ADD_REPLACE` adds a new extension if not present.
  EXPECT_EQ(
      1, X509_add1_ext_i2d(x509.get(), NID_basic_constraints, basic1_obj.get(),
                           /*crit=*/1, X509V3_ADD_REPLACE));
  expect_extensions({{NID_subject_key_identifier, true, skid2_der},
                     {NID_basic_constraints, true, basic1_der}});

  // Delete the extension again.
  EXPECT_EQ(1, X509_add1_ext_i2d(x509.get(), NID_basic_constraints, nullptr, 0,
                                 X509V3_ADD_DELETE));
  expect_extensions({{NID_subject_key_identifier, true, skid2_der}});

  // `X509V3_ADD_KEEP_EXISTING` adds a new extension if not present.
  EXPECT_EQ(
      1, X509_add1_ext_i2d(x509.get(), NID_basic_constraints, basic1_obj.get(),
                           /*crit=*/1, X509V3_ADD_KEEP_EXISTING));
  expect_extensions({{NID_subject_key_identifier, true, skid2_der},
                     {NID_basic_constraints, true, basic1_der}});

  // Delete the extension again.
  EXPECT_EQ(1, X509_add1_ext_i2d(x509.get(), NID_basic_constraints, nullptr, 0,
                                 X509V3_ADD_DELETE));
  expect_extensions({{NID_subject_key_identifier, true, skid2_der}});

  // `X509V3_ADD_APPEND` adds a new extension if not present.
  EXPECT_EQ(
      1, X509_add1_ext_i2d(x509.get(), NID_basic_constraints, basic1_obj.get(),
                           /*crit=*/1, X509V3_ADD_APPEND));
  expect_extensions({{NID_subject_key_identifier, true, skid2_der},
                     {NID_basic_constraints, true, basic1_der}});

  // `X509V3_ADD_APPEND` keeps adding duplicates (invalid) even if present.
  EXPECT_EQ(
      1, X509_add1_ext_i2d(x509.get(), NID_basic_constraints, basic2_obj.get(),
                           /*crit=*/0, X509V3_ADD_APPEND));
  expect_extensions({{NID_subject_key_identifier, true, skid2_der},
                     {NID_basic_constraints, true, basic1_der},
                     {NID_basic_constraints, false, basic2_der}});

  // `X509V3_ADD_DELETE` only deletes one extension at a time.
  EXPECT_EQ(1, X509_add1_ext_i2d(x509.get(), NID_basic_constraints, nullptr, 0,
                                 X509V3_ADD_DELETE));
  expect_extensions({{NID_subject_key_identifier, true, skid2_der},
                     {NID_basic_constraints, false, basic2_der}});
  EXPECT_EQ(1, X509_add1_ext_i2d(x509.get(), NID_basic_constraints, nullptr, 0,
                                 X509V3_ADD_DELETE));
  expect_extensions({{NID_subject_key_identifier, true, skid2_der}});
}

TEST(X509Test, NameEntry) {
  UniquePtr<X509_NAME> name(X509_NAME_new());
  ASSERT_TRUE(name);

  auto check_name = [&](const char *expected_rfc2253) {
    // Check RDN indices are self-consistent.
    int num = X509_NAME_entry_count(name.get());
    if (num > 0) {
      // RDN indices must start at zero.
      EXPECT_EQ(0, X509_NAME_ENTRY_set(X509_NAME_get_entry(name.get(), 0)));
    }
    for (int i = 1; i < num; i++) {
      int prev = X509_NAME_ENTRY_set(X509_NAME_get_entry(name.get(), i - 1));
      int current = X509_NAME_ENTRY_set(X509_NAME_get_entry(name.get(), i));
      // RDN indices must increase consecutively.
      EXPECT_TRUE(prev == current || prev + 1 == current)
          << "Entry " << i << " has RDN index " << current
          << " which is inconsistent with previous index " << prev;
    }

    // Check the name based on the RFC 2253 serialization. Note the RFC 2253
    // serialization is in reverse.
    UniquePtr<BIO> bio(BIO_new(BIO_s_mem()));
    ASSERT_TRUE(bio);
    EXPECT_GE(X509_NAME_print_ex(bio.get(), name.get(), 0, XN_FLAG_RFC2253), 0);
    const uint8_t *data;
    size_t len;
    ASSERT_TRUE(BIO_mem_contents(bio.get(), &data, &len));
    EXPECT_EQ(expected_rfc2253, std::string(data, data + len));
  };

  check_name("");

  // `loc` = -1, `set` = 0 appends as new RDNs.
  ASSERT_TRUE(X509_NAME_add_entry_by_NID(
      name.get(), NID_organizationName, MBSTRING_UTF8,
      reinterpret_cast<const unsigned char *>("Org"), /*len=*/-1, /*loc=*/-1,
      /*set=*/0));
  check_name("O=Org");

  // `loc` = -1, `set` = 0 appends as new RDNs.
  ASSERT_TRUE(X509_NAME_add_entry_by_NID(
      name.get(), NID_commonName, MBSTRING_UTF8,
      reinterpret_cast<const unsigned char *>("Name"), /*len=*/-1, /*loc=*/-1,
      /*set=*/0));
  check_name("CN=Name,O=Org");

  // Inserting in the middle of the set, but with `set` = 0 inserts a new RDN
  // and fixes the "set" values as needed.
  ASSERT_TRUE(X509_NAME_add_entry_by_NID(
      name.get(), NID_organizationalUnitName, MBSTRING_UTF8,
      reinterpret_cast<const unsigned char *>("Unit"), /*len=*/-1, /*loc=*/1,
      /*set=*/0));
  check_name("CN=Name,OU=Unit,O=Org");

  // `set = -1` adds to the previous entry's RDN. (Although putting O and OU at
  // the same level makes little sense, the test is written this way to check
  // the function isn't using attribute types to order things.)
  ASSERT_TRUE(X509_NAME_add_entry_by_NID(
      name.get(), NID_organizationName, MBSTRING_UTF8,
      reinterpret_cast<const unsigned char *>("Org2"), /*len=*/-1, /*loc=*/2,
      /*set=*/-1));
  check_name("CN=Name,O=Org2+OU=Unit,O=Org");

  // `set` = 1 adds to the next entry's RDN.
  ASSERT_TRUE(X509_NAME_add_entry_by_NID(
      name.get(), NID_commonName, MBSTRING_UTF8,
      reinterpret_cast<const unsigned char *>("Name2"), /*len=*/-1, /*loc=*/2,
      /*set=*/-1));
  check_name("CN=Name,O=Org2+CN=Name2+OU=Unit,O=Org");

  // If there is no previous RDN, `set` = -1 makes a new RDN.
  ASSERT_TRUE(X509_NAME_add_entry_by_NID(
      name.get(), NID_countryName, MBSTRING_UTF8,
      reinterpret_cast<const unsigned char *>("US"), /*len=*/-1, /*loc=*/0,
      /*set=*/-1));
  check_name("CN=Name,O=Org2+CN=Name2+OU=Unit,O=Org,C=US");

  // Likewise if there is no next RDN.
  ASSERT_TRUE(X509_NAME_add_entry_by_NID(
      name.get(), NID_commonName, MBSTRING_UTF8,
      reinterpret_cast<const unsigned char *>("Name3"), /*len=*/-1, /*loc=*/-1,
      /*set=*/1));
  check_name("CN=Name3,CN=Name,O=Org2+CN=Name2+OU=Unit,O=Org,C=US");

  // If `set` = 0 and we insert in the middle of an existing RDN, it adds an
  // RDN boundary after the entry but not before. This is a quirk of how the
  // function is implemented and hopefully not something any caller depends on.
  ASSERT_TRUE(X509_NAME_add_entry_by_NID(
      name.get(), NID_commonName, MBSTRING_UTF8,
      reinterpret_cast<const unsigned char *>("Name4"), /*len=*/-1, /*loc=*/3,
      /*set=*/0));
  check_name("CN=Name3,CN=Name,O=Org2+CN=Name2,CN=Name4+OU=Unit,O=Org,C=US");

  // Entries may be deleted.
  X509_NAME_ENTRY_free(X509_NAME_delete_entry(name.get(), 7));
  check_name("CN=Name,O=Org2+CN=Name2,CN=Name4+OU=Unit,O=Org,C=US");

  // When deleting the only attribute in an RDN, index invariants should still
  // hold.
  X509_NAME_ENTRY_free(X509_NAME_delete_entry(name.get(), 0));
  check_name("CN=Name,O=Org2+CN=Name2,CN=Name4+OU=Unit,O=Org");

  // Index invariants also hold when deleting attributes from non-singular RDNs.
  X509_NAME_ENTRY_free(X509_NAME_delete_entry(name.get(), 1));
  check_name("CN=Name,O=Org2+CN=Name2,CN=Name4,O=Org");
  X509_NAME_ENTRY_free(X509_NAME_delete_entry(name.get(), 1));
  check_name("CN=Name,O=Org2+CN=Name2,O=Org");

  // Same as above, but delete the second attribute first.
  X509_NAME_ENTRY_free(X509_NAME_delete_entry(name.get(), 2));
  check_name("CN=Name,CN=Name2,O=Org");
  X509_NAME_ENTRY_free(X509_NAME_delete_entry(name.get(), 1));
  check_name("CN=Name,O=Org");
}

// Tests that non-integer types are rejected when passed as an argument to
// X509_set_serialNumber().
TEST(X509Test, SetSerialNumberChecksASN1StringType) {
  UniquePtr<X509> root = CertFromPEM(kRootCAPEM);
  ASSERT_TRUE(root);

  // Passing an IA5String to X509_set_serialNumber() should fail.
  UniquePtr<ASN1_IA5STRING> str(ASN1_IA5STRING_new());
  ASSERT_TRUE(str);
  EXPECT_FALSE(X509_set_serialNumber(root.get(), str.get()));

  // Passing a negative serial number is allowed. While invalid, we do accept
  // them and some callers rely in this for tests.
  UniquePtr<ASN1_INTEGER> serial(ASN1_INTEGER_new());
  ASSERT_TRUE(serial);
  ASSERT_TRUE(ASN1_INTEGER_set_int64(serial.get(), -1));
  ASSERT_TRUE(X509_set_serialNumber(root.get(), serial.get()));
  int64_t val;
  ASSERT_TRUE(ASN1_INTEGER_get_int64(&val, X509_get0_serialNumber(root.get())));
  EXPECT_EQ(-1, val);
}

TEST(X509Test, Policy) {
  UniquePtr<ASN1_OBJECT> oid1(
      OBJ_txt2obj("1.2.840.113554.4.1.72585.2.1", /*dont_search_names=*/1));
  ASSERT_TRUE(oid1);
  UniquePtr<ASN1_OBJECT> oid2(
      OBJ_txt2obj("1.2.840.113554.4.1.72585.2.2", /*dont_search_names=*/1));
  ASSERT_TRUE(oid2);
  UniquePtr<ASN1_OBJECT> oid3(
      OBJ_txt2obj("1.2.840.113554.4.1.72585.2.3", /*dont_search_names=*/1));
  ASSERT_TRUE(oid3);
  UniquePtr<ASN1_OBJECT> oid4(
      OBJ_txt2obj("1.2.840.113554.4.1.72585.2.4", /*dont_search_names=*/1));
  ASSERT_TRUE(oid4);
  UniquePtr<ASN1_OBJECT> oid5(
      OBJ_txt2obj("1.2.840.113554.4.1.72585.2.5", /*dont_search_names=*/1));
  ASSERT_TRUE(oid5);

  UniquePtr<X509> root(
      CertFromPEM(GetTestData("crypto/x509/test/policy_root.pem")));
  ASSERT_TRUE(root);
  UniquePtr<X509> root_cross_inhibit_mapping(CertFromPEM(
      GetTestData("crypto/x509/test/policy_root_cross_inhibit_mapping.pem")));
  ASSERT_TRUE(root_cross_inhibit_mapping);
  UniquePtr<X509> root2(
      CertFromPEM(GetTestData("crypto/x509/test/policy_root2.pem")));
  ASSERT_TRUE(root2);
  UniquePtr<X509> intermediate(
      CertFromPEM(GetTestData("crypto/x509/test/policy_intermediate.pem")));
  ASSERT_TRUE(intermediate);
  UniquePtr<X509> intermediate_any(
      CertFromPEM(GetTestData("crypto/x509/test/policy_intermediate_any.pem")));
  ASSERT_TRUE(intermediate_any);
  UniquePtr<X509> intermediate_duplicate(CertFromPEM(
      GetTestData("crypto/x509/test/policy_intermediate_duplicate.pem")));
  ASSERT_TRUE(intermediate_duplicate);
  UniquePtr<X509> intermediate_invalid(CertFromPEM(
      GetTestData("crypto/x509/test/policy_intermediate_invalid.pem")));
  ASSERT_TRUE(intermediate_invalid);
  UniquePtr<X509> intermediate_mapped(CertFromPEM(
      GetTestData("crypto/x509/test/policy_intermediate_mapped.pem")));
  ASSERT_TRUE(intermediate_mapped);
  UniquePtr<X509> intermediate_mapped_any(CertFromPEM(
      GetTestData("crypto/x509/test/policy_intermediate_mapped_any.pem")));
  ASSERT_TRUE(intermediate_mapped_any);
  UniquePtr<X509> intermediate_mapped_oid3(CertFromPEM(
      GetTestData("crypto/x509/test/policy_intermediate_mapped_oid3.pem")));
  ASSERT_TRUE(intermediate_mapped_oid3);
  UniquePtr<X509> intermediate_require(CertFromPEM(
      GetTestData("crypto/x509/test/policy_intermediate_require.pem")));
  ASSERT_TRUE(intermediate_require);
  UniquePtr<X509> intermediate_require1(CertFromPEM(
      GetTestData("crypto/x509/test/policy_intermediate_require1.pem")));
  ASSERT_TRUE(intermediate_require1);
  UniquePtr<X509> intermediate_require2(CertFromPEM(
      GetTestData("crypto/x509/test/policy_intermediate_require2.pem")));
  ASSERT_TRUE(intermediate_require2);
  UniquePtr<X509> intermediate_require_duplicate(CertFromPEM(GetTestData(
      "crypto/x509/test/policy_intermediate_require_duplicate.pem")));
  ASSERT_TRUE(intermediate_require_duplicate);
  UniquePtr<X509> intermediate_require_no_policies(CertFromPEM(GetTestData(
      "crypto/x509/test/policy_intermediate_require_no_policies.pem")));
  ASSERT_TRUE(intermediate_require_no_policies);
  UniquePtr<X509> leaf(
      CertFromPEM(GetTestData("crypto/x509/test/policy_leaf.pem")));
  ASSERT_TRUE(leaf);
  UniquePtr<X509> leaf_any(
      CertFromPEM(GetTestData("crypto/x509/test/policy_leaf_any.pem")));
  ASSERT_TRUE(leaf_any);
  UniquePtr<X509> leaf_duplicate(
      CertFromPEM(GetTestData("crypto/x509/test/policy_leaf_duplicate.pem")));
  ASSERT_TRUE(leaf_duplicate);
  UniquePtr<X509> leaf_invalid(
      CertFromPEM(GetTestData("crypto/x509/test/policy_leaf_invalid.pem")));
  ASSERT_TRUE(leaf_invalid);
  UniquePtr<X509> leaf_none(
      CertFromPEM(GetTestData("crypto/x509/test/policy_leaf_none.pem")));
  ASSERT_TRUE(leaf_none);
  UniquePtr<X509> leaf_oid1(
      CertFromPEM(GetTestData("crypto/x509/test/policy_leaf_oid1.pem")));
  ASSERT_TRUE(leaf_oid1);
  UniquePtr<X509> leaf_oid2(
      CertFromPEM(GetTestData("crypto/x509/test/policy_leaf_oid2.pem")));
  ASSERT_TRUE(leaf_oid2);
  UniquePtr<X509> leaf_oid3(
      CertFromPEM(GetTestData("crypto/x509/test/policy_leaf_oid3.pem")));
  ASSERT_TRUE(leaf_oid3);
  UniquePtr<X509> leaf_oid4(
      CertFromPEM(GetTestData("crypto/x509/test/policy_leaf_oid4.pem")));
  ASSERT_TRUE(leaf_oid4);
  UniquePtr<X509> leaf_oid5(
      CertFromPEM(GetTestData("crypto/x509/test/policy_leaf_oid5.pem")));
  ASSERT_TRUE(leaf_oid5);
  UniquePtr<X509> leaf_require(
      CertFromPEM(GetTestData("crypto/x509/test/policy_leaf_require.pem")));
  ASSERT_TRUE(leaf_require);
  UniquePtr<X509> leaf_require1(
      CertFromPEM(GetTestData("crypto/x509/test/policy_leaf_require1.pem")));
  ASSERT_TRUE(leaf_require1);

  auto set_policies = [](X509_STORE_CTX *ctx,
                         std::vector<const ASN1_OBJECT *> oids) {
    X509_VERIFY_PARAM *param = X509_STORE_CTX_get0_param(ctx);
    for (const ASN1_OBJECT *oid : oids) {
      UniquePtr<ASN1_OBJECT> copy(OBJ_dup(oid));
      ASSERT_TRUE(copy);
      ASSERT_TRUE(X509_VERIFY_PARAM_add0_policy(param, copy.get()));
      copy.release();  // `X509_VERIFY_PARAM_add0_policy` takes ownership on
                       // success.
    }
  };

  // The chain is good for `oid1` and `oid2`, but not `oid3`.
  EXPECT_EQ(X509_V_OK, Verify(leaf.get(), {root.get()}, {intermediate.get()},
                              /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY));
  EXPECT_EQ(X509_V_OK,
            Verify(leaf.get(), {root.get()}, {intermediate.get()}, /*crls=*/{},
                   X509_V_FLAG_EXPLICIT_POLICY, [&](X509_STORE_CTX *ctx) {
                     set_policies(ctx, {oid1.get()});
                   }));
  EXPECT_EQ(X509_V_OK,
            Verify(leaf.get(), {root.get()}, {intermediate.get()}, /*crls=*/{},
                   X509_V_FLAG_EXPLICIT_POLICY, [&](X509_STORE_CTX *ctx) {
                     set_policies(ctx, {oid2.get()});
                   }));
  EXPECT_EQ(X509_V_ERR_NO_EXPLICIT_POLICY,
            Verify(leaf.get(), {root.get()}, {intermediate.get()}, /*crls=*/{},
                   X509_V_FLAG_EXPLICIT_POLICY, [&](X509_STORE_CTX *ctx) {
                     set_policies(ctx, {oid3.get()});
                   }));
  EXPECT_EQ(X509_V_OK,
            Verify(leaf.get(), {root.get()}, {intermediate.get()}, /*crls=*/{},
                   X509_V_FLAG_EXPLICIT_POLICY, [&](X509_STORE_CTX *ctx) {
                     set_policies(ctx, {oid1.get(), oid2.get()});
                   }));
  EXPECT_EQ(X509_V_OK,
            Verify(leaf.get(), {root.get()}, {intermediate.get()}, /*crls=*/{},
                   X509_V_FLAG_EXPLICIT_POLICY, [&](X509_STORE_CTX *ctx) {
                     set_policies(ctx, {oid1.get(), oid3.get()});
                   }));

  // The policy extension cannot be parsed.
  EXPECT_EQ(
      X509_V_ERR_INVALID_POLICY_EXTENSION,
      Verify(leaf.get(), {root.get()}, {intermediate_invalid.get()},
             /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
             [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid1.get()}); }));
  EXPECT_EQ(
      X509_V_ERR_INVALID_POLICY_EXTENSION,
      Verify(leaf_invalid.get(), {root.get()}, {intermediate.get()},
             /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
             [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid1.get()}); }));
  EXPECT_EQ(X509_V_ERR_INVALID_POLICY_EXTENSION,
            Verify(leaf_invalid.get(), {root.get()}, {intermediate.get()},
                   /*crls=*/{}));

  // There is a duplicate policy in the policy extension.
  EXPECT_EQ(
      X509_V_ERR_INVALID_POLICY_EXTENSION,
      Verify(leaf.get(), {root.get()}, {intermediate_duplicate.get()},
             /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
             [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid1.get()}); }));

  // The policy extension in the leaf cannot be parsed.
  EXPECT_EQ(
      X509_V_ERR_INVALID_POLICY_EXTENSION,
      Verify(leaf_duplicate.get(), {root.get()}, {intermediate.get()},
             /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
             [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid1.get()}); }));

  // Without `X509_V_FLAG_EXPLICIT_POLICY`, the policy tree is built and
  // intersected with user-specified policies, but it is not required to result
  // in any valid policies.
  EXPECT_EQ(X509_V_OK,
            Verify(leaf.get(), {root.get()}, {intermediate.get()}, /*crls=*/{},
                   /*flags=*/0, [&](X509_STORE_CTX *ctx) {
                     set_policies(ctx, {oid1.get()});
                   }));
  EXPECT_EQ(X509_V_OK,
            Verify(leaf.get(), {root.get()}, {intermediate.get()}, /*crls=*/{},
                   /*flags=*/0, [&](X509_STORE_CTX *ctx) {
                     set_policies(ctx, {oid3.get()});
                   }));

  // However, a CA with policy constraints can require an explicit policy.
  EXPECT_EQ(X509_V_OK, Verify(leaf.get(), {root.get()},
                              {intermediate_require.get()}, /*crls=*/{},
                              /*flags=*/0, [&](X509_STORE_CTX *ctx) {
                                set_policies(ctx, {oid1.get()});
                              }));
  EXPECT_EQ(X509_V_ERR_NO_EXPLICIT_POLICY,
            Verify(leaf.get(), {root.get()}, {intermediate_require.get()},
                   /*crls=*/{},
                   /*flags=*/0, [&](X509_STORE_CTX *ctx) {
                     set_policies(ctx, {oid3.get()});
                   }));

  // requireExplicitPolicy applies even if the application does not configure a
  // user-initial-policy-set. If the validation results in no policies, the
  // chain is invalid.
  EXPECT_EQ(X509_V_ERR_NO_EXPLICIT_POLICY,
            Verify(leaf_none.get(), {root.get()}, {intermediate_require.get()},
                   /*crls=*/{}));

  // A leaf can also set requireExplicitPolicy.
  EXPECT_EQ(X509_V_OK,
            Verify(leaf_require.get(), {root.get()}, {intermediate.get()},
                   /*crls=*/{}, /*flags=*/0));
  EXPECT_EQ(X509_V_OK, Verify(leaf_require.get(), {root.get()},
                              {intermediate.get()}, /*crls=*/{},
                              /*flags=*/0, [&](X509_STORE_CTX *ctx) {
                                set_policies(ctx, {oid1.get()});
                              }));
  EXPECT_EQ(X509_V_ERR_NO_EXPLICIT_POLICY,
            Verify(leaf_require.get(), {root.get()}, {intermediate.get()},
                   /*crls=*/{},
                   /*flags=*/0, [&](X509_STORE_CTX *ctx) {
                     set_policies(ctx, {oid3.get()});
                   }));

  // requireExplicitPolicy is a count of certificates to skip. If the value is
  // not zero by the end of the chain, it doesn't count.
  EXPECT_EQ(X509_V_ERR_NO_EXPLICIT_POLICY,
            Verify(leaf.get(), {root.get()}, {intermediate_require1.get()},
                   /*crls=*/{},
                   /*flags=*/0, [&](X509_STORE_CTX *ctx) {
                     set_policies(ctx, {oid3.get()});
                   }));
  EXPECT_EQ(X509_V_OK,
            Verify(leaf.get(), {root.get()}, {intermediate_require2.get()},
                   /*crls=*/{},
                   /*flags=*/0, [&](X509_STORE_CTX *ctx) {
                     set_policies(ctx, {oid3.get()});
                   }));
  EXPECT_EQ(X509_V_OK,
            Verify(leaf_require1.get(), {root.get()}, {intermediate.get()},
                   /*crls=*/{},
                   /*flags=*/0, [&](X509_STORE_CTX *ctx) {
                     set_policies(ctx, {oid3.get()});
                   }));

  // If multiple certificates specify the constraint, the more constrained value
  // wins.
  EXPECT_EQ(
      X509_V_ERR_NO_EXPLICIT_POLICY,
      Verify(leaf_require1.get(), {root.get()}, {intermediate_require1.get()},
             /*crls=*/{},
             /*flags=*/0,
             [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid3.get()}); }));
  EXPECT_EQ(
      X509_V_ERR_NO_EXPLICIT_POLICY,
      Verify(leaf_require.get(), {root.get()}, {intermediate_require2.get()},
             /*crls=*/{},
             /*flags=*/0,
             [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid3.get()}); }));

  // An intermediate that requires an explicit policy, but then specifies no
  // policies should fail verification as a result.
  EXPECT_EQ(X509_V_ERR_NO_EXPLICIT_POLICY,
            Verify(leaf.get(), {root.get()},
                   {intermediate_require_no_policies.get()}, /*crls=*/{},
                   /*flags=*/0, [&](X509_STORE_CTX *ctx) {
                     set_policies(ctx, {oid1.get()});
                   }));

  // A constrained intermediate's policy extension has a duplicate policy, which
  // is invalid. Historically this, and the above case, leaked memory.
  EXPECT_EQ(X509_V_ERR_INVALID_POLICY_EXTENSION,
            Verify(leaf.get(), {root.get()},
                   {intermediate_require_duplicate.get()}, /*crls=*/{},
                   /*flags=*/0, [&](X509_STORE_CTX *ctx) {
                     set_policies(ctx, {oid1.get()});
                   }));

  // The leaf asserts anyPolicy, but the intermediate does not. The resulting
  // valid policies are the intersection.
  EXPECT_EQ(
      X509_V_OK,
      Verify(leaf_any.get(), {root.get()}, {intermediate.get()}, /*crls=*/{},
             X509_V_FLAG_EXPLICIT_POLICY,
             [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid1.get()}); }));
  EXPECT_EQ(
      X509_V_ERR_NO_EXPLICIT_POLICY,
      Verify(leaf_any.get(), {root.get()}, {intermediate.get()}, /*crls=*/{},
             X509_V_FLAG_EXPLICIT_POLICY,
             [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid3.get()}); }));

  // The intermediate asserts anyPolicy, but the leaf does not. The resulting
  // valid policies are the intersection.
  EXPECT_EQ(
      X509_V_OK,
      Verify(leaf.get(), {root.get()}, {intermediate_any.get()}, /*crls=*/{},
             X509_V_FLAG_EXPLICIT_POLICY,
             [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid1.get()}); }));
  EXPECT_EQ(
      X509_V_ERR_NO_EXPLICIT_POLICY,
      Verify(leaf.get(), {root.get()}, {intermediate_any.get()}, /*crls=*/{},
             X509_V_FLAG_EXPLICIT_POLICY,
             [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid3.get()}); }));

  // Both assert anyPolicy. All policies are valid.
  EXPECT_EQ(
      X509_V_OK,
      Verify(leaf_any.get(), {root.get()}, {intermediate_any.get()},
             /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
             [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid1.get()}); }));
  EXPECT_EQ(
      X509_V_OK,
      Verify(leaf_any.get(), {root.get()}, {intermediate_any.get()},
             /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
             [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid3.get()}); }));

  // With just a trust anchor, policy checking silently succeeds.
  EXPECT_EQ(X509_V_OK, Verify(root.get(), {root.get()}, {},
                              /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
                              [&](X509_STORE_CTX *ctx) {
                                set_policies(ctx, {oid1.get()});
                              }));

  for (bool use_any : {false, true}) {
    SCOPED_TRACE(use_any);
    X509 *cert =
        use_any ? intermediate_mapped_any.get() : intermediate_mapped.get();
    // OID3 is mapped to {OID1, OID2}, which means OID1 and OID2 (or both) are
    // acceptable for OID3.
    EXPECT_EQ(X509_V_OK, Verify(leaf.get(), {root.get()}, {cert},
                                /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
                                [&](X509_STORE_CTX *ctx) {
                                  set_policies(ctx, {oid3.get()});
                                }));
    EXPECT_EQ(X509_V_OK, Verify(leaf_oid1.get(), {root.get()}, {cert},
                                /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
                                [&](X509_STORE_CTX *ctx) {
                                  set_policies(ctx, {oid3.get()});
                                }));
    EXPECT_EQ(X509_V_OK, Verify(leaf_oid2.get(), {root.get()}, {cert},
                                /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
                                [&](X509_STORE_CTX *ctx) {
                                  set_policies(ctx, {oid3.get()});
                                }));

    // If the intermediate's policies were anyPolicy, OID3 at the leaf, despite
    // being mapped, is still acceptable as OID3 at the root. Despite the OID3
    // having expected_policy_set = {OID1, OID2}, it can match the anyPolicy
    // node instead.
    //
    // If the intermediate's policies listed OIDs explicitly, OID3 at the leaf
    // is not acceptable as OID3 at the root. OID3 has expected_polciy_set =
    // {OID1, OID2} and no other node allows OID3.
    EXPECT_EQ(
        use_any ? X509_V_OK : X509_V_ERR_NO_EXPLICIT_POLICY,
        Verify(leaf_oid3.get(), {root.get()}, {cert},
               /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
               [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid3.get()}); }));

    // If the intermediate's policies were anyPolicy, OID1 at the leaf is no
    // longer acceptable as OID1 at the root because policies only match
    // anyPolicy when they match no other policy.
    //
    // If the intermediate's policies listed OIDs explicitly, OID1 at the leaf
    // is acceptable as OID1 at the root because it will match both OID1 and
    // OID3 (mapped) policies.
    EXPECT_EQ(
        use_any ? X509_V_ERR_NO_EXPLICIT_POLICY : X509_V_OK,
        Verify(leaf_oid1.get(), {root.get()}, {cert},
               /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
               [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid1.get()}); }));

    // All pairs of OID4 and OID5 are mapped together, so either can stand for
    // the other.
    EXPECT_EQ(X509_V_OK, Verify(leaf_oid4.get(), {root.get()}, {cert},
                                /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
                                [&](X509_STORE_CTX *ctx) {
                                  set_policies(ctx, {oid4.get()});
                                }));
    EXPECT_EQ(X509_V_OK, Verify(leaf_oid4.get(), {root.get()}, {cert},
                                /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
                                [&](X509_STORE_CTX *ctx) {
                                  set_policies(ctx, {oid5.get()});
                                }));
    EXPECT_EQ(X509_V_OK, Verify(leaf_oid5.get(), {root.get()}, {cert},
                                /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
                                [&](X509_STORE_CTX *ctx) {
                                  set_policies(ctx, {oid4.get()});
                                }));
    EXPECT_EQ(X509_V_OK, Verify(leaf_oid5.get(), {root.get()}, {cert},
                                /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
                                [&](X509_STORE_CTX *ctx) {
                                  set_policies(ctx, {oid5.get()});
                                }));

    EXPECT_EQ(X509_V_OK, Verify(leaf_oid4.get(), {root.get()}, {cert},
                                /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
                                [&](X509_STORE_CTX *ctx) {
                                  set_policies(ctx, {oid4.get(), oid5.get()});
                                }));
  }

  // Although `intermediate_mapped_oid3` contains many mappings, it only accepts
  // OID3. Nodes should not be created for the other mappings.
  EXPECT_EQ(
      X509_V_OK,
      Verify(leaf_oid1.get(), {root.get()}, {intermediate_mapped_oid3.get()},
             /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
             [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid3.get()}); }));
  EXPECT_EQ(
      X509_V_ERR_NO_EXPLICIT_POLICY,
      Verify(leaf_oid4.get(), {root.get()}, {intermediate_mapped_oid3.get()},
             /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
             [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid4.get()}); }));

  // Policy mapping can be inhibited, either by the caller or a certificate in
  // the chain, in which case mapped policies are unassertable (apart from some
  // anyPolicy edge cases).
  EXPECT_EQ(
      X509_V_ERR_NO_EXPLICIT_POLICY,
      Verify(leaf_oid1.get(), {root.get()}, {intermediate_mapped_oid3.get()},
             /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY | X509_V_FLAG_INHIBIT_MAP,
             [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid3.get()}); }));
  EXPECT_EQ(
      X509_V_ERR_NO_EXPLICIT_POLICY,
      Verify(leaf_oid1.get(), {root2.get()},
             {intermediate_mapped_oid3.get(), root_cross_inhibit_mapping.get()},
             /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
             [&](X509_STORE_CTX *ctx) { set_policies(ctx, {oid3.get()}); }));
}

#if defined(OPENSSL_THREADS)
// A similar test to the above, but ensures the various bits of intermediate
// state are computed safely.
TEST(X509Test, PolicyThreads) {
  const size_t kNumThreads = 10;

  UniquePtr<ASN1_OBJECT> oid1(
      OBJ_txt2obj("1.2.840.113554.4.1.72585.2.1", /*dont_search_names=*/1));
  ASSERT_TRUE(oid1);
  UniquePtr<ASN1_OBJECT> oid2(
      OBJ_txt2obj("1.2.840.113554.4.1.72585.2.2", /*dont_search_names=*/1));
  ASSERT_TRUE(oid2);
  UniquePtr<ASN1_OBJECT> oid3(
      OBJ_txt2obj("1.2.840.113554.4.1.72585.2.3", /*dont_search_names=*/1));
  ASSERT_TRUE(oid3);

  auto set_policies = [](X509_STORE_CTX *ctx,
                         std::vector<const ASN1_OBJECT *> oids) {
    X509_VERIFY_PARAM *param = X509_STORE_CTX_get0_param(ctx);
    for (const ASN1_OBJECT *oid : oids) {
      UniquePtr<ASN1_OBJECT> copy(OBJ_dup(oid));
      ASSERT_TRUE(copy);
      ASSERT_TRUE(X509_VERIFY_PARAM_add0_policy(param, copy.get()));
      copy.release();  // `X509_VERIFY_PARAM_add0_policy` takes ownership on
                       // success.
    }
  };

  {
    UniquePtr<X509> root(
        CertFromPEM(GetTestData("crypto/x509/test/policy_root.pem")));
    ASSERT_TRUE(root);
    UniquePtr<X509> intermediate(
        CertFromPEM(GetTestData("crypto/x509/test/policy_intermediate.pem")));
    ASSERT_TRUE(intermediate);
    UniquePtr<X509> leaf(
        CertFromPEM(GetTestData("crypto/x509/test/policy_leaf.pem")));
    ASSERT_TRUE(leaf);

    std::vector<std::thread> threads;
    for (size_t i = 0; i < kNumThreads; i++) {
      threads.emplace_back([&] {
        EXPECT_EQ(
            X509_V_OK,
            Verify(leaf.get(), {root.get()}, {intermediate.get()}, /*crls=*/{},
                   X509_V_FLAG_EXPLICIT_POLICY, [&](X509_STORE_CTX *ctx) {
                     set_policies(ctx, {oid1.get()});
                   }));
      });
    }
    for (auto &thread : threads) {
      thread.join();
    }
  }

  {
    UniquePtr<X509> root(
        CertFromPEM(GetTestData("crypto/x509/test/policy_root.pem")));
    ASSERT_TRUE(root);
    UniquePtr<X509> intermediate(
        CertFromPEM(GetTestData("crypto/x509/test/policy_intermediate.pem")));
    ASSERT_TRUE(intermediate);
    UniquePtr<X509> leaf_invalid(
        CertFromPEM(GetTestData("crypto/x509/test/policy_leaf_invalid.pem")));
    ASSERT_TRUE(leaf_invalid);


    std::vector<std::thread> threads;
    for (size_t i = 0; i < kNumThreads; i++) {
      threads.emplace_back([&] {
        EXPECT_EQ(X509_V_ERR_INVALID_POLICY_EXTENSION,
                  Verify(leaf_invalid.get(), {root.get()}, {intermediate.get()},
                         /*crls=*/{}, X509_V_FLAG_EXPLICIT_POLICY,
                         [&](X509_STORE_CTX *ctx) {
                           set_policies(ctx, {oid1.get()});
                         }));
      });
    }
    for (auto &thread : threads) {
      thread.join();
    }
  }
}
#endif  // OPENSSL_THREADS

TEST(X509Test, ExtensionFromConf) {
  static const char kTestOID[] = "1.2.840.113554.4.1.72585.2";
  const struct {
    const char *name;
    std::string value;
    // conf is the serialized confdb, or nullptr if none is to be provided.
    const char *conf;
    // expected is the resulting extension, encoded in DER, or the empty string
    // if an error is expected.
    std::vector<uint8_t> expected;
  } kTests[] = {
      // Many extensions have built-in syntax.
      {"basicConstraints",
       "critical,CA:true",
       nullptr,
       {0x30, 0x0f, 0x06, 0x03, 0x55, 0x1d, 0x13, 0x01, 0x01, 0xff, 0x04, 0x05,
        0x30, 0x03, 0x01, 0x01, 0xff}},

      {"basicConstraints",
       "critical,CA:true,pathlen:1",
       nullptr,
       {0x30, 0x12, 0x06, 0x03, 0x55, 0x1d, 0x13, 0x01, 0x01, 0xff,
        0x04, 0x08, 0x30, 0x06, 0x01, 0x01, 0xff, 0x02, 0x01, 0x01}},

      // key:value tuples can be repeated and just override the previous value.
      {"basicConstraints",
       "critical,CA:true,pathlen:100,pathlen:1",
       nullptr,
       {0x30, 0x12, 0x06, 0x03, 0x55, 0x1d, 0x13, 0x01, 0x01, 0xff,
        0x04, 0x08, 0x30, 0x06, 0x01, 0x01, 0xff, 0x02, 0x01, 0x01}},

      // Extension contents may be referenced from a config section.
      {"basicConstraints",
       "critical,@section",
       "[section]\nCA = true\n",
       {0x30, 0x0f, 0x06, 0x03, 0x55, 0x1d, 0x13, 0x01, 0x01, 0xff, 0x04, 0x05,
        0x30, 0x03, 0x01, 0x01, 0xff}},

      // If no config is provided, this should fail.
      {"basicConstraints", "critical,@section", nullptr, {}},

      // issuingDistributionPoint takes a list of name:value pairs. Omitting the
      // value is not allowed.
      {"issuingDistributionPoint", "fullname", nullptr, {}},
      {"issuingDistributionPoint", "relativename", nullptr, {}},

      // issuingDistributionPoint can specify a nameRelativeToCRLIssuer by
      // section.
      {"issuingDistributionPoint",
       "relativename:name",
       "[name]\nCN=Hello\n",
       {0x30, 0x1b, 0x06, 0x03, 0x55, 0x1d, 0x1c, 0x04, 0x14, 0x30,
        0x12, 0xa0, 0x10, 0xa1, 0x0e, 0x30, 0x0c, 0x06, 0x03, 0x55,
        0x04, 0x03, 0x0c, 0x05, 0x48, 0x65, 0x6c, 0x6c, 0x6f}},

      // relativename referencing a section which doesn't exist.
      {"issuingDistributionPoint",
       "relativename:wrong_section_name",
       "[name]\nCN=Hello\n",
       {}},

      // relativename must be a single RDN. By default, the section-based name
      // syntax puts each attribute into its own RDN.
      {"issuingDistributionPoint",
       "relativename:name",
       "[name]\nCN=Hello\nC=US\n",
       {}},

      // A single RDN with multiple attributes is allowed.
      {"issuingDistributionPoint",
       "relativename:name",
       "[name]\nCN=Hello\n+C=US\n",
       {0x30, 0x26, 0x06, 0x03, 0x55, 0x1d, 0x1c, 0x04, 0x1f, 0x30,
        0x1d, 0xa0, 0x1b, 0xa1, 0x19, 0x30, 0x09, 0x06, 0x03, 0x55,
        0x04, 0x06, 0x13, 0x02, 0x55, 0x53, 0x30, 0x0c, 0x06, 0x03,
        0x55, 0x04, 0x03, 0x0c, 0x05, 0x48, 0x65, 0x6c, 0x6c, 0x6f}},

      // issuingDistributionPoint can specify a fullName by section or inline.
      {"issuingDistributionPoint",
       "fullname:URI:http://example.com/",
       nullptr,
       {0x30, 0x22, 0x06, 0x03, 0x55, 0x1d, 0x1c, 0x04, 0x1b,
        0x30, 0x19, 0xa0, 0x17, 0xa0, 0x15, 0x86, 0x13, 0x68,
        0x74, 0x74, 0x70, 0x3a, 0x2f, 0x2f, 0x65, 0x78, 0x61,
        0x6d, 0x70, 0x6c, 0x65, 0x2e, 0x63, 0x6f, 0x6d, 0x2f}},
      {"issuingDistributionPoint",
       "fullname:@name",
       "[name]\nURI.1=https://example.com/1\nURI.2=https://example.com/2",
       {0x30, 0x3b, 0x06, 0x03, 0x55, 0x1d, 0x1c, 0x04, 0x34, 0x30, 0x32,
        0xa0, 0x30, 0xa0, 0x2e, 0x86, 0x15, 0x68, 0x74, 0x74, 0x70, 0x73,
        0x3a, 0x2f, 0x2f, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x2e,
        0x63, 0x6f, 0x6d, 0x2f, 0x31, 0x86, 0x15, 0x68, 0x74, 0x74, 0x70,
        0x73, 0x3a, 0x2f, 0x2f, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65,
        0x2e, 0x63, 0x6f, 0x6d, 0x2f, 0x32}},

      // The inline form of fullName can take multiple values, but only when the
      // whole value is indirected through a section. Otherwise
      // `X509V3_parse_list` splits it by commas too early.
      {"issuingDistributionPoint",
       "@idp",
       "[idp]\nfullname = URI:https://example.com/1, URI:https://example.com/2",
       {0x30, 0x3b, 0x06, 0x03, 0x55, 0x1d, 0x1c, 0x04, 0x34, 0x30, 0x32,
        0xa0, 0x30, 0xa0, 0x2e, 0x86, 0x15, 0x68, 0x74, 0x74, 0x70, 0x73,
        0x3a, 0x2f, 0x2f, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x2e,
        0x63, 0x6f, 0x6d, 0x2f, 0x31, 0x86, 0x15, 0x68, 0x74, 0x74, 0x70,
        0x73, 0x3a, 0x2f, 0x2f, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65,
        0x2e, 0x63, 0x6f, 0x6d, 0x2f, 0x32}},

      // Multiple distribution point names are an error, either two full, two
      // relative, or one of each.
      {"issuingDistributionPoint",
       "fullname:URI:http://a.example/, fullname:URI:http://b.example",
       nullptr,
       {}},
      {"issuingDistributionPoint",
       "fullname:URI:http://a.example/, relativename:name",
       "[name]\nCN=Hello\n",
       {}},
      {"issuingDistributionPoint",
       "relativename:name, fullname:URI:http://a.example/",
       "[name]\nCN=Hello\n",
       {}},
      {"issuingDistributionPoint",
       "relativename:name1, relativename:name2",
       "[name1]\nCN=Hello\n[name2]\nCN=World\n",
       {}},

      // Duplicate reason keys are an error. Reaching this case is interesting.
      // The value can a string like "key:value,key:value", or it can be
      // "@section" and reference a config section. If using a string, duplicate
      // keys are possible, but then it is impossible to put commas in the
      // value, as onlysomereasons expects. If using a section reference, it is
      // impossible to have a duplicate key because the config file parser
      // overrides the old value.
      {"issuingDistributionPoint",
       "onlysomereasons:keyCompromise",
       nullptr,
       {0x30, 0x0d, 0x06, 0x03, 0x55, 0x1d, 0x1c, 0x04, 0x06, 0x30, 0x04, 0x83,
        0x02, 0x06, 0x40}},
      {"issuingDistributionPoint",
       "onlysomereasons:keyCompromise,onlysomereasons:CACompromise\n",
       nullptr,
       {}},

      // crlDistributionPoints takes a series of key/value pairs, each of which
      // becomes a distribution point. If a pair has a value, this is a
      // shorthand to specify a GeneralName, which goes into a single
      // distribution point as its sole fullName value. Otherwise, the key is a
      // second reference which specifies the distribution point.
      {"crlDistributionPoints",
       "dp1, dp2, dp3, dp4, URI:http://a.example, DNS:example.com",
       R"(
# Empty distribution point. This is not actually allowed, but OpenSSL's config
# syntax will construct it.
[dp1]

# A fullName with multiple names.
[dp2]
fullname = URI:http://a.example, URI:http://b.example

# A nameRelativeToCRLIssuer, with all the other options.
[dp3]
relativename = relname
reasons = keyCompromise, CACompromise
CRLissuer = dirName:crlissuer
# Unknown keys are silently ignored. This is probably a bug.
foo = bar
[relname]
CN = Test
[crlissuer]
CN = CRL Issuer

# cRLIssuer is, for some reason, a GeneralNames, yet RFC 5280 says "If present,
# the cRLIssuer MUST only contain the distinguished name (DN) from the issuer
# field of the CRL to which the DistributionPoint is pointing." While invalid by
# this text, it is syntactically possible in both X.509 and OpenSSL's ad-hoc
# config language to specify a multi-valued GeneralNames with non-DN SAN types.
[dp4]
CRLissuer = URI:http://example.com, DNS:example.com, IP:127.0.0.1
)",
       {0x30, 0x81, 0xbf, 0x06, 0x03, 0x55, 0x1d, 0x1f, 0x04, 0x81, 0xb7, 0x30,
        0x81, 0xb4, 0x30, 0x00, 0x30, 0x28, 0xa0, 0x26, 0xa0, 0x24, 0x86, 0x10,
        0x68, 0x74, 0x74, 0x70, 0x3a, 0x2f, 0x2f, 0x61, 0x2e, 0x65, 0x78, 0x61,
        0x6d, 0x70, 0x6c, 0x65, 0x86, 0x10, 0x68, 0x74, 0x74, 0x70, 0x3a, 0x2f,
        0x2f, 0x62, 0x2e, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x30, 0x30,
        0xa0, 0x0f, 0xa1, 0x0d, 0x30, 0x0b, 0x06, 0x03, 0x55, 0x04, 0x03, 0x0c,
        0x04, 0x54, 0x65, 0x73, 0x74, 0x81, 0x02, 0x05, 0x60, 0xa2, 0x19, 0xa4,
        0x17, 0x30, 0x15, 0x31, 0x13, 0x30, 0x11, 0x06, 0x03, 0x55, 0x04, 0x03,
        0x0c, 0x0a, 0x43, 0x52, 0x4c, 0x20, 0x49, 0x73, 0x73, 0x75, 0x65, 0x72,
        0x30, 0x29, 0xa2, 0x27, 0x86, 0x12, 0x68, 0x74, 0x74, 0x70, 0x3a, 0x2f,
        0x2f, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x2e, 0x63, 0x6f, 0x6d,
        0x82, 0x0b, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x2e, 0x63, 0x6f,
        0x6d, 0x87, 0x04, 0x7f, 0x00, 0x00, 0x01, 0x30, 0x16, 0xa0, 0x14, 0xa0,
        0x12, 0x86, 0x10, 0x68, 0x74, 0x74, 0x70, 0x3a, 0x2f, 0x2f, 0x61, 0x2e,
        0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x30, 0x11, 0xa0, 0x0f, 0xa0,
        0x0d, 0x82, 0x0b, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x2e, 0x63,
        0x6f, 0x6d}},

      // Multiple distribution point names within a single CRL distribution
      // point are an error. Unlike issuingDistributionPoint, this seems to be
      // only reachable by mixing full and relative in one distribution point.
      // There is no inline form for this extension and, within a section, it is
      // impossible to have a duplicate key because the parser silently
      // overrides the old key.
      {"crlDistributionPoints",
       "dp",
       R"([dp]
fullname = URI:http://a.example
relativename = relname
[relname]
CN = Test)",
       {}},

      // subjectAltName has a series of string-based inputs for each name type.
      {"subjectAltName",
       "email:foo@example.com, URI:https://example.com, DNS:example.com, "
       "RID:1.2.3.4, IP:127.0.0.1, IP:::1, dirName:section, "
       "otherName:1.2.3.4;BOOLEAN:TRUE",
       "[section]\nCN=Test\n",
       {0x30, 0x78, 0x06, 0x03, 0x55, 0x1d, 0x11, 0x04, 0x71, 0x30, 0x6f, 0x81,
        0x0f, 0x66, 0x6f, 0x6f, 0x40, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65,
        0x2e, 0x63, 0x6f, 0x6d, 0x86, 0x13, 0x68, 0x74, 0x74, 0x70, 0x73, 0x3a,
        0x2f, 0x2f, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x2e, 0x63, 0x6f,
        0x6d, 0x82, 0x0b, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x2e, 0x63,
        0x6f, 0x6d, 0x88, 0x03, 0x2a, 0x03, 0x04, 0x87, 0x04, 0x7f, 0x00, 0x00,
        0x01, 0x87, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xa4, 0x11, 0x30, 0x0f, 0x31,
        0x0d, 0x30, 0x0b, 0x06, 0x03, 0x55, 0x04, 0x03, 0x0c, 0x04, 0x54, 0x65,
        0x73, 0x74, 0xa0, 0x0a, 0x06, 0x03, 0x2a, 0x03, 0x04, 0xa0, 0x03, 0x01,
        0x01, 0xff}},

      // Syntax errors in each case, where they exist. (The string types just
      // copy the string in as-is.)
      {"subjectAltName", "RID:not_an_oid", nullptr, {}},
      {"subjectAltName", "IP:not_an_ip", nullptr, {}},
      {"subjectAltName", "dirName:no_conf_db", nullptr, {}},
      {"subjectAltName", "dirName:missing_section", "[section]\nCN=Test\n", {}},
      {"subjectAltName", "otherName:missing_semicolon", nullptr, {}},
      {"subjectAltName", "otherName:1.2.3.4", nullptr, {}},
      {"subjectAltName", "otherName:invalid_oid;BOOLEAN:TRUE", nullptr, {}},
      {"subjectAltName", "otherName:1.2.3.4;invalid_value", nullptr, {}},

      {"policyMappings",
       "1.1.1.1:2.2.2.2",
       nullptr,
       {0x30, 0x15, 0x06, 0x03, 0x55, 0x1d, 0x21, 0x04, 0x0e, 0x30, 0x0c, 0x30,
        0x0a, 0x06, 0x03, 0x29, 0x01, 0x01, 0x06, 0x03, 0x52, 0x02, 0x02}},
      {"policyMappings", "invalid_oid:2.2.2.2", nullptr, {}},
      {"policyMappings", "1.1.1.1:invalid_oid", nullptr, {}},

      // authorityInfoAccess is a comma-separated list of
      // accessMethod;accessLocation tuples, where the latter specifies a
      // GeneralName.
      {"authorityInfoAccess",
       "caIssuers;URI:http://example.com/1, "
       "caIssuers;URI:http://example.com/2, OCSP;URI:http://example.com/3, "
       "OCSP;DNS:non-uri-does-not-make-sense-but-is-allowed.test",
       nullptr,
       {0x30, 0x81, 0xb3, 0x06, 0x08, 0x2b, 0x06, 0x01, 0x05, 0x05, 0x07, 0x01,
        0x01, 0x04, 0x81, 0xa6, 0x30, 0x81, 0xa3, 0x30, 0x20, 0x06, 0x08, 0x2b,
        0x06, 0x01, 0x05, 0x05, 0x07, 0x30, 0x02, 0x86, 0x14, 0x68, 0x74, 0x74,
        0x70, 0x3a, 0x2f, 0x2f, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x2e,
        0x63, 0x6f, 0x6d, 0x2f, 0x31, 0x30, 0x20, 0x06, 0x08, 0x2b, 0x06, 0x01,
        0x05, 0x05, 0x07, 0x30, 0x02, 0x86, 0x14, 0x68, 0x74, 0x74, 0x70, 0x3a,
        0x2f, 0x2f, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x2e, 0x63, 0x6f,
        0x6d, 0x2f, 0x32, 0x30, 0x20, 0x06, 0x08, 0x2b, 0x06, 0x01, 0x05, 0x05,
        0x07, 0x30, 0x01, 0x86, 0x14, 0x68, 0x74, 0x74, 0x70, 0x3a, 0x2f, 0x2f,
        0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x2e, 0x63, 0x6f, 0x6d, 0x2f,
        0x33, 0x30, 0x3b, 0x06, 0x08, 0x2b, 0x06, 0x01, 0x05, 0x05, 0x07, 0x30,
        0x01, 0x82, 0x2f, 0x6e, 0x6f, 0x6e, 0x2d, 0x75, 0x72, 0x69, 0x2d, 0x64,
        0x6f, 0x65, 0x73, 0x2d, 0x6e, 0x6f, 0x74, 0x2d, 0x6d, 0x61, 0x6b, 0x65,
        0x2d, 0x73, 0x65, 0x6e, 0x73, 0x65, 0x2d, 0x62, 0x75, 0x74, 0x2d, 0x69,
        0x73, 0x2d, 0x61, 0x6c, 0x6c, 0x6f, 0x77, 0x65, 0x64, 0x2e, 0x74, 0x65,
        0x73, 0x74}},

      // nameConstraints puts a "permitted" or "excluded" prefix on the key
      // name.
      {"nameConstraints",
       "permitted.DNS:example.com",
       nullptr,
       {0x30, 0x1a, 0x06, 0x03, 0x55, 0x1d, 0x1e, 0x04, 0x13, 0x30,
        0x11, 0xa0, 0x0f, 0x30, 0x0d, 0x82, 0x0b, 0x65, 0x78, 0x61,
        0x6d, 0x70, 0x6c, 0x65, 0x2e, 0x63, 0x6f, 0x6d}},
      {"nameConstraints",
       "permitted_DNS:example.com",
       nullptr,
       {0x30, 0x1a, 0x06, 0x03, 0x55, 0x1d, 0x1e, 0x04, 0x13, 0x30,
        0x11, 0xa0, 0x0f, 0x30, 0x0d, 0x82, 0x0b, 0x65, 0x78, 0x61,
        0x6d, 0x70, 0x6c, 0x65, 0x2e, 0x63, 0x6f, 0x6d}},
      {"nameConstraints",
       "excluded.DNS:example.com, excluded.email:example.com",
       nullptr,
       {0x30, 0x29, 0x06, 0x03, 0x55, 0x1d, 0x1e, 0x04, 0x22, 0x30, 0x20,
        0xa1, 0x1e, 0x30, 0x0d, 0x82, 0x0b, 0x65, 0x78, 0x61, 0x6d, 0x70,
        0x6c, 0x65, 0x2e, 0x63, 0x6f, 0x6d, 0x30, 0x0d, 0x81, 0x0b, 0x65,
        0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x2e, 0x63, 0x6f, 0x6d}},
      {"nameConstraints",
       "permitted.DNS.1:example.com, permitted.DNS.2:example.net, "
       "excluded.DNS.1:nope.example.com, excluded.DNS.2:also-nope.example.com",
       nullptr,
       {0x30, 0x58, 0x06, 0x03, 0x55, 0x1d, 0x1e, 0x04, 0x51, 0x30, 0x4f, 0xa0,
        0x1e, 0x30, 0x0d, 0x82, 0x0b, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65,
        0x2e, 0x63, 0x6f, 0x6d, 0x30, 0x0d, 0x82, 0x0b, 0x65, 0x78, 0x61, 0x6d,
        0x70, 0x6c, 0x65, 0x2e, 0x6e, 0x65, 0x74, 0xa1, 0x2d, 0x30, 0x12, 0x82,
        0x10, 0x6e, 0x6f, 0x70, 0x65, 0x2e, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c,
        0x65, 0x2e, 0x63, 0x6f, 0x6d, 0x30, 0x17, 0x82, 0x15, 0x61, 0x6c, 0x73,
        0x6f, 0x2d, 0x6e, 0x6f, 0x70, 0x65, 0x2e, 0x65, 0x78, 0x61, 0x6d, 0x70,
        0x6c, 0x65, 0x2e, 0x63, 0x6f, 0x6d}},

      // Invalid prefixes.
      {"nameConstraints", "permit:example.com", nullptr, {}},
      {"nameConstraints", "permitted:example.com", nullptr, {}},
      {"nameConstraints", "permitted.nope:example.com", nullptr, {}},
      {"nameConstraints", "exclude:example.com", nullptr, {}},
      {"nameConstraints", "excluded:example.com", nullptr, {}},
      {"nameConstraints", "excluded.nope:example.com", nullptr, {}},

      // The "DER:" prefix just specifies an arbitrary byte string. Colons
      // separators are ignored.
      {kTestOID, "DER:0001020304", nullptr, {0x30, 0x15, 0x06, 0x0c, 0x2a, 0x86,
                                             0x48, 0x86, 0xf7, 0x12, 0x04, 0x01,
                                             0x84, 0xb7, 0x09, 0x02, 0x04, 0x05,
                                             0x00, 0x01, 0x02, 0x03, 0x04}},
      {kTestOID,
       "DER:00:01:02:03:04",
       nullptr,
       {0x30, 0x15, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04, 0x01,
        0x84, 0xb7, 0x09, 0x02, 0x04, 0x05, 0x00, 0x01, 0x02, 0x03, 0x04}},
      {kTestOID, "DER:invalid hex", nullptr, {}},

      // The "ASN1:" prefix implements a complex language for describing ASN.1
      // structures. See
      // https://www.openssl.org/docs/man1.1.1/man3/ASN1_generate_nconf.html
      {kTestOID, "ASN1:invalid", nullptr, {}},
      {kTestOID,
       "ASN1:BOOLEAN:TRUE",
       nullptr,
       {0x30, 0x13, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
        0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x03, 0x01, 0x01, 0xff}},
      {kTestOID, "ASN1:BOOL:yes", nullptr, {0x30, 0x13, 0x06, 0x0c, 0x2a, 0x86,
                                            0x48, 0x86, 0xf7, 0x12, 0x04, 0x01,
                                            0x84, 0xb7, 0x09, 0x02, 0x04, 0x03,
                                            0x01, 0x01, 0xff}},
      {kTestOID,
       "ASN1:BOOLEAN:NO",
       nullptr,
       {0x30, 0x13, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
        0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x03, 0x01, 0x01, 0x00}},
      {kTestOID,
       "ASN1:BOOLEAN",  // Missing value
       nullptr,
       {}},
      {kTestOID, "ASN1:BOOLEAN:invalid", nullptr, {}},
      {kTestOID, "ASN1:BOOLEAN:TRUE,invalid", nullptr, {}},

      {kTestOID, "ASN1:NULL", nullptr, {0x30, 0x12, 0x06, 0x0c, 0x2a,
                                        0x86, 0x48, 0x86, 0xf7, 0x12,
                                        0x04, 0x01, 0x84, 0xb7, 0x09,
                                        0x02, 0x04, 0x02, 0x05, 0x00}},
      {kTestOID, "ASN1:NULL,invalid", nullptr, {}},
      {kTestOID, "ASN1:NULL:invalid", nullptr, {}},

      // Missing value.
      {kTestOID, "ASN1:INTEGER", nullptr, {}},
      {kTestOID, "ASN1:INTEGER:", nullptr, {}},
      {kTestOID, "ASN1:INTEGER,invalid", nullptr, {}},

      // INTEGER may be decimal or hexadecimal.
      {kTestOID, "ASN1:INT:-0x10", nullptr, {0x30, 0x13, 0x06, 0x0c, 0x2a, 0x86,
                                             0x48, 0x86, 0xf7, 0x12, 0x04, 0x01,
                                             0x84, 0xb7, 0x09, 0x02, 0x04, 0x03,
                                             0x02, 0x01, 0xf0}},
      {kTestOID, "ASN1:INT:-10", nullptr, {0x30, 0x13, 0x06, 0x0c, 0x2a, 0x86,
                                           0x48, 0x86, 0xf7, 0x12, 0x04, 0x01,
                                           0x84, 0xb7, 0x09, 0x02, 0x04, 0x03,
                                           0x02, 0x01, 0xf6}},
      {kTestOID, "ASN1:INT:0", nullptr, {0x30, 0x13, 0x06, 0x0c, 0x2a, 0x86,
                                         0x48, 0x86, 0xf7, 0x12, 0x04, 0x01,
                                         0x84, 0xb7, 0x09, 0x02, 0x04, 0x03,
                                         0x02, 0x01, 0x00}},
      {kTestOID,
       "ASN1:INTEGER:10",
       nullptr,
       {0x30, 0x13, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
        0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x03, 0x02, 0x01, 0x0a}},
      {kTestOID,
       "ASN1:INTEGER:0x10",
       nullptr,
       {0x30, 0x13, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
        0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x03, 0x02, 0x01, 0x10}},

      {kTestOID, "ASN1:ENUM:0", nullptr, {0x30, 0x13, 0x06, 0x0c, 0x2a, 0x86,
                                          0x48, 0x86, 0xf7, 0x12, 0x04, 0x01,
                                          0x84, 0xb7, 0x09, 0x02, 0x04, 0x03,
                                          0x0a, 0x01, 0x00}},
      {kTestOID,
       "ASN1:ENUMERATED:0",
       nullptr,
       {0x30, 0x13, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
        0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x03, 0x0a, 0x01, 0x00}},

      // OIDs may be spelled out or specified by name.
      {kTestOID, "ASN1:OBJECT:invalid", nullptr, {}},
      {kTestOID,
       "ASN1:OBJECT:basicConstraints",
       nullptr,
       {0x30, 0x15, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04, 0x01,
        0x84, 0xb7, 0x09, 0x02, 0x04, 0x05, 0x06, 0x03, 0x55, 0x1d, 0x13}},
      {kTestOID,
       "ASN1:OBJECT:2.5.29.19",
       nullptr,
       {0x30, 0x15, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04, 0x01,
        0x84, 0xb7, 0x09, 0x02, 0x04, 0x05, 0x06, 0x03, 0x55, 0x1d, 0x13}},
      {kTestOID,
       "ASN1:OID:2.5.29.19",
       nullptr,
       {0x30, 0x15, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04, 0x01,
        0x84, 0xb7, 0x09, 0x02, 0x04, 0x05, 0x06, 0x03, 0x55, 0x1d, 0x13}},

      {kTestOID, "ASN1:UTC:invalid", nullptr, {}},
      {kTestOID, "ASN1:UTC:20001231235959Z", nullptr, {}},
      {kTestOID, "ASN1:UTCTIME:invalid", nullptr, {}},
      {kTestOID,
       "ASN1:UTC:001231235959Z",
       nullptr,
       {0x30, 0x1f, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
        0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x0f, 0x17, 0x0d, 0x30, 0x30,
        0x31, 0x32, 0x33, 0x31, 0x32, 0x33, 0x35, 0x39, 0x35, 0x39, 0x5a}},
      {kTestOID,
       "ASN1:UTCTIME:001231235959Z",
       nullptr,
       {0x30, 0x1f, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
        0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x0f, 0x17, 0x0d, 0x30, 0x30,
        0x31, 0x32, 0x33, 0x31, 0x32, 0x33, 0x35, 0x39, 0x35, 0x39, 0x5a}},

      {kTestOID, "ASN1:GENTIME:invalid", nullptr, {}},
      {kTestOID, "ASN1:GENTIME:001231235959Z", nullptr, {}},
      {kTestOID, "ASN1:GENERALIZEDTIME:invalid", nullptr, {}},
      {kTestOID,
       "ASN1:GENTIME:20001231235959Z",
       nullptr,
       {0x30, 0x21, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04, 0x01,
        0x84, 0xb7, 0x09, 0x02, 0x04, 0x11, 0x18, 0x0f, 0x32, 0x30, 0x30, 0x30,
        0x31, 0x32, 0x33, 0x31, 0x32, 0x33, 0x35, 0x39, 0x35, 0x39, 0x5a}},
      {kTestOID,
       "ASN1:GENERALIZEDTIME:20001231235959Z",
       nullptr,
       {0x30, 0x21, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04, 0x01,
        0x84, 0xb7, 0x09, 0x02, 0x04, 0x11, 0x18, 0x0f, 0x32, 0x30, 0x30, 0x30,
        0x31, 0x32, 0x33, 0x31, 0x32, 0x33, 0x35, 0x39, 0x35, 0x39, 0x5a}},

      // The default input format for string types is ASCII, which is then
      // converted into the target string type.
      {kTestOID, "ASN1:UTF8:hello", nullptr, {0x30, 0x17, 0x06, 0x0c, 0x2a,
                                              0x86, 0x48, 0x86, 0xf7, 0x12,
                                              0x04, 0x01, 0x84, 0xb7, 0x09,
                                              0x02, 0x04, 0x07, 0x0c, 0x05,
                                              0x68, 0x65, 0x6c, 0x6c, 0x6f}},
      {kTestOID,
       "ASN1:UTF8String:hello",
       nullptr,
       {0x30, 0x17, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7,
        0x12, 0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x07,
        0x0c, 0x05, 0x68, 0x65, 0x6c, 0x6c, 0x6f}},
      {kTestOID,
       "ASN1:UNIV:hello",
       nullptr,
       {0x30, 0x26, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12,
        0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x16, 0x1c, 0x14,
        0x00, 0x00, 0x00, 0x68, 0x00, 0x00, 0x00, 0x65, 0x00, 0x00,
        0x00, 0x6c, 0x00, 0x00, 0x00, 0x6c, 0x00, 0x00, 0x00, 0x6f}},
      {kTestOID,
       "ASN1:UNIVERSALSTRING:hello",
       nullptr,
       {0x30, 0x26, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12,
        0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x16, 0x1c, 0x14,
        0x00, 0x00, 0x00, 0x68, 0x00, 0x00, 0x00, 0x65, 0x00, 0x00,
        0x00, 0x6c, 0x00, 0x00, 0x00, 0x6c, 0x00, 0x00, 0x00, 0x6f}},
      {kTestOID,
       "ASN1:BMP:hello",
       nullptr,
       {0x30, 0x1c, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12,
        0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x0c, 0x1e, 0x0a,
        0x00, 0x68, 0x00, 0x65, 0x00, 0x6c, 0x00, 0x6c, 0x00, 0x6f}},
      {kTestOID,
       "ASN1:BMPSTRING:hello",
       nullptr,
       {0x30, 0x1c, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12,
        0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x0c, 0x1e, 0x0a,
        0x00, 0x68, 0x00, 0x65, 0x00, 0x6c, 0x00, 0x6c, 0x00, 0x6f}},
      {kTestOID, "ASN1:IA5:hello", nullptr, {0x30, 0x17, 0x06, 0x0c, 0x2a,
                                             0x86, 0x48, 0x86, 0xf7, 0x12,
                                             0x04, 0x01, 0x84, 0xb7, 0x09,
                                             0x02, 0x04, 0x07, 0x16, 0x05,
                                             0x68, 0x65, 0x6c, 0x6c, 0x6f}},
      {kTestOID,
       "ASN1:IA5STRING:hello",
       nullptr,
       {0x30, 0x17, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7,
        0x12, 0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x07,
        0x16, 0x05, 0x68, 0x65, 0x6c, 0x6c, 0x6f}},
      {kTestOID,
       "ASN1:PRINTABLE:hello",
       nullptr,
       {0x30, 0x17, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7,
        0x12, 0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x07,
        0x13, 0x05, 0x68, 0x65, 0x6c, 0x6c, 0x6f}},
      {kTestOID,
       "ASN1:PRINTABLESTRING:hello",
       nullptr,
       {0x30, 0x17, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7,
        0x12, 0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x07,
        0x13, 0x05, 0x68, 0x65, 0x6c, 0x6c, 0x6f}},
      {kTestOID, "ASN1:T61:hello", nullptr, {0x30, 0x17, 0x06, 0x0c, 0x2a,
                                             0x86, 0x48, 0x86, 0xf7, 0x12,
                                             0x04, 0x01, 0x84, 0xb7, 0x09,
                                             0x02, 0x04, 0x07, 0x14, 0x05,
                                             0x68, 0x65, 0x6c, 0x6c, 0x6f}},
      {kTestOID,
       "ASN1:T61STRING:hello",
       nullptr,
       {0x30, 0x17, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7,
        0x12, 0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x07,
        0x14, 0x05, 0x68, 0x65, 0x6c, 0x6c, 0x6f}},
      {kTestOID,
       "ASN1:TELETEXSTRING:hello",
       nullptr,
       {0x30, 0x17, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7,
        0x12, 0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x07,
        0x14, 0x05, 0x68, 0x65, 0x6c, 0x6c, 0x6f}},

      // FORMAT:UTF8 switches the input format to UTF-8. This should be
      // converted to the destination string, or rejected if invalid.
      {kTestOID,
       "ASN1:FORMAT:UTF8,UTF8:\xe2\x98\x83",
       nullptr,
       {0x30, 0x15, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04, 0x01,
        0x84, 0xb7, 0x09, 0x02, 0x04, 0x05, 0x0c, 0x03, 0xe2, 0x98, 0x83}},
      {kTestOID,
       "ASN1:FORMAT:UTF8,UNIV:\xe2\x98\x83",
       nullptr,
       {0x30, 0x16, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86,
        0xf7, 0x12, 0x04, 0x01, 0x84, 0xb7, 0x09, 0x02,
        0x04, 0x06, 0x1c, 0x04, 0x00, 0x00, 0x26, 0x03}},
      {kTestOID,
       "ASN1:FORMAT:UTF8,BMP:\xe2\x98\x83",
       nullptr,
       {0x30, 0x14, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
        0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x04, 0x1e, 0x02, 0x26, 0x03}},
      {kTestOID, "ASN1:FORMAT:UTF8,IA5:\xe2\x98\x83", nullptr, {}},
      {kTestOID,
       "ASN1:FORMAT:UTF8,IA5:hello",
       nullptr,
       {0x30, 0x17, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7,
        0x12, 0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x07,
        0x16, 0x05, 0x68, 0x65, 0x6c, 0x6c, 0x6f}},
      {kTestOID, "ASN1:FORMAT:UTF8,PRINTABLE:\xe2\x98\x83", nullptr, {}},
      {kTestOID,
       "ASN1:FORMAT:UTF8,PRINTABLE:hello",
       nullptr,
       {0x30, 0x17, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7,
        0x12, 0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x07,
        0x13, 0x05, 0x68, 0x65, 0x6c, 0x6c, 0x6f}},
      {kTestOID, "ASN1:FORMAT:UTF8,T61:\xe2\x98\x83", nullptr, {}},
      {kTestOID,
       "ASN1:FORMAT:UTF8,T61:\xc3\xb7",
       nullptr,
       {0x30, 0x13, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
        0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x03, 0x14, 0x01, 0xf7}},

      // Invalid UTF-8.
      {kTestOID, "ASN1:FORMAT:UTF8,UTF8:\xff", nullptr, {}},

      // We don't support these string types.
      {kTestOID, "ASN1:NUMERIC:0", nullptr, {}},
      {kTestOID, "ASN1:NUMERICSTRING:0", nullptr, {}},
      {kTestOID, "ASN1:VISIBLE:hello", nullptr, {}},
      {kTestOID, "ASN1:VISIBLESTRING:hello", nullptr, {}},
      {kTestOID, "ASN1:GeneralString:hello", nullptr, {}},

      // OCTET STRING and BIT STRING also default to ASCII, but also accept HEX.
      // BIT STRING interprets OCTET STRING formats by having zero unused bits.
      {kTestOID, "ASN1:OCT:hello", nullptr, {0x30, 0x17, 0x06, 0x0c, 0x2a,
                                             0x86, 0x48, 0x86, 0xf7, 0x12,
                                             0x04, 0x01, 0x84, 0xb7, 0x09,
                                             0x02, 0x04, 0x07, 0x04, 0x05,
                                             0x68, 0x65, 0x6c, 0x6c, 0x6f}},
      {kTestOID,
       "ASN1:OCTETSTRING:hello",
       nullptr,
       {0x30, 0x17, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7,
        0x12, 0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x07,
        0x04, 0x05, 0x68, 0x65, 0x6c, 0x6c, 0x6f}},
      {kTestOID,
       "ASN1:FORMAT:HEX,OCT:0123abcd",
       nullptr,
       {0x30, 0x16, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86,
        0xf7, 0x12, 0x04, 0x01, 0x84, 0xb7, 0x09, 0x02,
        0x04, 0x06, 0x04, 0x04, 0x01, 0x23, 0xab, 0xcd}},
      {kTestOID,
       "ASN1:BITSTR:hello",
       nullptr,
       {0x30, 0x18, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7,
        0x12, 0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x08,
        0x03, 0x06, 0x00, 0x68, 0x65, 0x6c, 0x6c, 0x6f}},
      {kTestOID,
       "ASN1:BITSTRING:hello",
       nullptr,
       {0x30, 0x18, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7,
        0x12, 0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x08,
        0x03, 0x06, 0x00, 0x68, 0x65, 0x6c, 0x6c, 0x6f}},
      {kTestOID,
       "ASN1:FORMAT:HEX,BITSTR:0123abcd",
       nullptr,
       {0x30, 0x17, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7,
        0x12, 0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x07,
        0x03, 0x05, 0x00, 0x01, 0x23, 0xab, 0xcd}},

      {kTestOID, "ASN1:FORMAT:HEX,OCT:invalid hex", nullptr, {}},

      // BIT STRING additionally supports a BITLIST type, which specifies a
      // list of bits to set.
      {kTestOID,
       "ASN1:FORMAT:BITLIST,BITSTR:1,5",
       nullptr,
       {0x30, 0x14, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
        0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x04, 0x03, 0x02, 0x02, 0x44}},

      {kTestOID, "ASN1:FORMAT:BITLIST,BITSTR:1,invalid,5", nullptr, {}},
      // Negative bit indices are not allowed.
      {kTestOID, "ASN1:FORMAT:BITLIST,BITSTR:-1", nullptr, {}},
      // We cap bit indices at 256.
      {kTestOID, "ASN1:FORMAT:BITLIST,BITSTR:257", nullptr, {}},
      {kTestOID,
       "ASN1:FORMAT:BITLIST,BITSTR:256",
       nullptr,
       {0x30, 0x34, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
        0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x24, 0x03, 0x22, 0x07, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80}},

      // Unsupported formats for string types.
      {kTestOID, "ASN1:FORMAT:BITLIST,IA5:abcd", nullptr, {}},
      {kTestOID, "ASN1:FORMAT:BITLIST,UTF8:abcd", nullptr, {}},
      {kTestOID, "ASN1:FORMAT:BITLIST,OCT:abcd", nullptr, {}},
      {kTestOID, "ASN1:FORMAT:BITLIST,UTC:abcd", nullptr, {}},
      {kTestOID, "ASN1:FORMAT:HEX,IA5:abcd", nullptr, {}},
      {kTestOID, "ASN1:FORMAT:HEX,UTF8:abcd", nullptr, {}},
      {kTestOID, "ASN1:FORMAT:HEX,UTC:abcd", nullptr, {}},
      {kTestOID, "ASN1:FORMAT:UTF8,OCT:abcd", nullptr, {}},
      {kTestOID, "ASN1:FORMAT:UTF8,UTC:abcd", nullptr, {}},

      // Invalid format type.
      {kTestOID, "ASN1:FORMAT:invalid,IA5:abcd", nullptr, {}},

      // SEQUENCE and SET encode empty values when there is no value.
      {kTestOID, "ASN1:SEQ", nullptr, {0x30, 0x12, 0x06, 0x0c, 0x2a, 0x86, 0x48,
                                       0x86, 0xf7, 0x12, 0x04, 0x01, 0x84, 0xb7,
                                       0x09, 0x02, 0x04, 0x02, 0x30, 0x00}},
      {kTestOID, "ASN1:SET", nullptr, {0x30, 0x12, 0x06, 0x0c, 0x2a, 0x86, 0x48,
                                       0x86, 0xf7, 0x12, 0x04, 0x01, 0x84, 0xb7,
                                       0x09, 0x02, 0x04, 0x02, 0x31, 0x00}},
      {kTestOID, "ASN1:SEQUENCE", nullptr, {0x30, 0x12, 0x06, 0x0c, 0x2a,
                                            0x86, 0x48, 0x86, 0xf7, 0x12,
                                            0x04, 0x01, 0x84, 0xb7, 0x09,
                                            0x02, 0x04, 0x02, 0x30, 0x00}},

      // Otherwise, they require a corresponding section in the config database
      // to encode values. This can be nested recursively.
      {kTestOID, "ASN1:SEQ:missing_confdb", nullptr, {}},
      {kTestOID, "ASN1:SET:missing_confdb", nullptr, {}},
      {kTestOID,
       "ASN1:SEQ:seq",
       R"(
[seq]
val1 = NULL
val2 = IA5:a
val3 = SET:set
[set]
# Config names do not matter, only the order.
val4 = INT:1
val3 = INT:2
val2 = SEQ:empty
val1 = INT:3
[empty]
)",
       {0x30, 0x24, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12,
        0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x14, 0x30, 0x12,
        0x05, 0x00, 0x16, 0x01, 0x61, 0x31, 0x0b, 0x02, 0x01, 0x01,
        0x02, 0x01, 0x02, 0x02, 0x01, 0x03, 0x30, 0x00}},

      // There is a recursion limit to stop infinite recursion.
      {kTestOID,
       "ASN1:SEQ:seq1",
       R"(
[seq1]
val = SEQ:seq2
[seq2]
val = SEQ:seq1
)",
       {}},

      // Various modifiers wrap with explicit tagging or universal types.
      {kTestOID,
       "ASN1:EXP:0,EXP:16U,EXP:100A,EXP:1000C,OCTWRAP,SEQWRAP,SETWRAP,BITWRAP,"
       "NULL",
       nullptr,
       {0x30, 0x26, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12,
        0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x16, 0xa0, 0x14,
        0x30, 0x12, 0x7f, 0x64, 0x0f, 0xbf, 0x87, 0x68, 0x0b, 0x04,
        0x09, 0x30, 0x07, 0x31, 0x05, 0x03, 0x03, 0x00, 0x05, 0x00}},

      // Invalid tag numbers.
      {kTestOID, "ASN1:EXP:-1,NULL", nullptr, {}},
      {kTestOID, "ASN1:EXP:1?,NULL", nullptr, {}},
      // Fits in `uint32_t` but exceeds `CBS_ASN1_TAG_NUMBER_MASK`, the largest
      // tag number we support.
      {kTestOID, "ASN1:EXP:536870912,NULL", nullptr, {}},

      // Implicit tagging may also be applied to the underlying type, or the
      // wrapping modifiers.
      {kTestOID,
       "ASN1:IMP:1A,OCTWRAP,IMP:10,SEQWRAP,IMP:100,SETWRAP,IMP:1000,BITWRAP,"
       "IMP:10000,NULL",
       nullptr,
       {0x30, 0x20, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04, 0x01,
        0x84, 0xb7, 0x09, 0x02, 0x04, 0x10, 0x41, 0x0e, 0xaa, 0x0c, 0xbf, 0x64,
        0x09, 0x9f, 0x87, 0x68, 0x05, 0x00, 0x9f, 0xce, 0x10, 0x00}},

      // Implicit tagging may not be applied to explicit tagging or itself.
      // There's no rule against this in ASN.1, but OpenSSL does not allow it
      // here.
      {kTestOID, "ASN1:IMP:1,EXP:1,NULL", nullptr, {}},
      {kTestOID, "ASN1:IMP:1,IMP:1,NULL", nullptr, {}},

      // [UNIVERSAL 0] is reserved.
      {kTestOID, "ASN1:0U,NULL", nullptr, {}},

      // Leading and trailing spaces on name:value pairs are removed. However,
      // while these pairs are delimited by commas, a type will consumes
      // everything after it, including commas, and spaces. So this is the
      // string " a, b ".
      {kTestOID,
       "ASN1: EXP:0 , IA5: a, b ",
       nullptr,
       {0x30, 0x1a, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12,
        0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x0a, 0xa0, 0x08,
        0x16, 0x06, 0x20, 0x61, 0x2c, 0x20, 0x62, 0x20}},

      // Modifiers without a final type.
      {kTestOID, "ASN1:EXP:1", nullptr, {}},

      // Put it all together to describe a test Ed25519 key (wrapped inside an
      // X.509 extension).
      {kTestOID,
       "ASN1:SEQUENCE:pkcs8",
       R"(
[pkcs8]
vers = INT:0
alg = SEQWRAP,OID:1.3.101.112
key = FORMAT:HEX,OCTWRAP,OCT:9d61b19deffd5a60ba844af492ec2cc44449c5697b326919703bac031cae7f60
)",
       {0x30, 0x40, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12, 0x04,
        0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x30, 0x30, 0x2e, 0x02, 0x01,
        0x00, 0x30, 0x05, 0x06, 0x03, 0x2b, 0x65, 0x70, 0x04, 0x22, 0x04,
        0x20, 0x9d, 0x61, 0xb1, 0x9d, 0xef, 0xfd, 0x5a, 0x60, 0xba, 0x84,
        0x4a, 0xf4, 0x92, 0xec, 0x2c, 0xc4, 0x44, 0x49, 0xc5, 0x69, 0x7b,
        0x32, 0x69, 0x19, 0x70, 0x3b, 0xac, 0x03, 0x1c, 0xae, 0x7f, 0x60}},

      // Sections can be referenced multiple times.
      {kTestOID,
       "ASN1:SEQUENCE:seq1",
       R"(
[seq1]
val1 = SEQUENCE:seq2
val2 = SEQUENCE:seq2
[seq2]
val1 = INT:1
val2 = INT:2
)",
       {0x30, 0x22, 0x06, 0x0c, 0x2a, 0x86, 0x48, 0x86, 0xf7,
        0x12, 0x04, 0x01, 0x84, 0xb7, 0x09, 0x02, 0x04, 0x12,
        0x30, 0x10, 0x30, 0x06, 0x02, 0x01, 0x01, 0x02, 0x01,
        0x02, 0x30, 0x06, 0x02, 0x01, 0x01, 0x02, 0x01, 0x02}},

      // But we cap this before it blows up exponentially.
      {kTestOID,
       "ASN1:SEQ:seq1",
       R"(
[seq1]
val1 = SEQ:seq2
val2 = SEQ:seq2
[seq2]
val1 = SEQ:seq3
val2 = SEQ:seq3
[seq3]
val1 = SEQ:seq4
val2 = SEQ:seq4
[seq4]
val1 = SEQ:seq5
val2 = SEQ:seq5
[seq5]
val1 = SEQ:seq6
val2 = SEQ:seq6
[seq6]
val1 = SEQ:seq7
val2 = SEQ:seq7
[seq7]
val1 = SEQ:seq8
val2 = SEQ:seq8
[seq8]
val1 = SEQ:seq9
val2 = SEQ:seq9
[seq9]
val1 = SEQ:seq10
val2 = SEQ:seq10
[seq10]
val1 = SEQ:seq11
val2 = SEQ:seq11
[seq11]
val1 = SEQ:seq12
val2 = SEQ:seq12
[seq12]
val1 = IA5:AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
val2 = IA5:BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
)",
       {}},

      // Integer sizes are capped to mitigate quadratic behavior.
      {kTestOID, "ASN1:INT:" + std::string(16384, '9'), nullptr, {}},

      // Certificate policies can be specified as OIDs.
      {"certificatePolicies",
       "1.2.3.4, anyPolicy",
       "",
       {0x30, 0x18, 0x06, 0x03, 0x55, 0x1d, 0x20, 0x04, 0x11,
        0x30, 0x0f, 0x30, 0x05, 0x06, 0x03, 0x2a, 0x03, 0x04,
        0x30, 0x06, 0x06, 0x04, 0x55, 0x1d, 0x20, 0x00}},

      // Or they may be specified by section.
      {"certificatePolicies",
       "@policy",
       R"(
[policy]
policyIdentifier = 1.2.3.4
)",
       {0x30, 0x10, 0x06, 0x03, 0x55, 0x1d, 0x20, 0x04, 0x09, 0x30, 0x07, 0x30,
        0x05, 0x06, 0x03, 0x2a, 0x03, 0x04}},

      // Specifying a section allows qualifiers to be included.
      {"certificatePolicies",
       "@policy",
       R"(
[policy]
policyIdentifier = 1.2.3.4
CPS = http://example.com/cps
userNotice = @notice
[notice]
explicitText = Hello World
organization = MyOrg
noticeNumbers = 1,2,3
)",
       {0x30, 0x65, 0x06, 0x03, 0x55, 0x1d, 0x20, 0x04, 0x5e, 0x30, 0x5c, 0x30,
        0x5a, 0x06, 0x03, 0x2a, 0x03, 0x04, 0x30, 0x53, 0x30, 0x22, 0x06, 0x08,
        0x2b, 0x06, 0x01, 0x05, 0x05, 0x07, 0x02, 0x01, 0x16, 0x16, 0x68, 0x74,
        0x74, 0x70, 0x3a, 0x2f, 0x2f, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65,
        0x2e, 0x63, 0x6f, 0x6d, 0x2f, 0x63, 0x70, 0x73, 0x30, 0x2d, 0x06, 0x08,
        0x2b, 0x06, 0x01, 0x05, 0x05, 0x07, 0x02, 0x02, 0x30, 0x21, 0x30, 0x12,
        0x1a, 0x05, 0x4d, 0x79, 0x4f, 0x72, 0x67, 0x30, 0x09, 0x02, 0x01, 0x01,
        0x02, 0x01, 0x02, 0x02, 0x01, 0x03, 0x1a, 0x0b, 0x48, 0x65, 0x6c, 0x6c,
        0x6f, 0x20, 0x57, 0x6f, 0x72, 0x6c, 0x64}},

      // The ia5org token flips the string type used in the organization name.
      {"certificatePolicies",
       "ia5org, @policy",
       R"(
[policy]
policyIdentifier = 1.2.3.4
CPS = http://example.com/cps
userNotice = @notice
[notice]
explicitText = Hello World
organization = MyOrg
noticeNumbers = 1,2,3
)",
       {0x30, 0x65, 0x06, 0x03, 0x55, 0x1d, 0x20, 0x04, 0x5e, 0x30, 0x5c, 0x30,
        0x5a, 0x06, 0x03, 0x2a, 0x03, 0x04, 0x30, 0x53, 0x30, 0x22, 0x06, 0x08,
        0x2b, 0x06, 0x01, 0x05, 0x05, 0x07, 0x02, 0x01, 0x16, 0x16, 0x68, 0x74,
        0x74, 0x70, 0x3a, 0x2f, 0x2f, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65,
        0x2e, 0x63, 0x6f, 0x6d, 0x2f, 0x63, 0x70, 0x73, 0x30, 0x2d, 0x06, 0x08,
        0x2b, 0x06, 0x01, 0x05, 0x05, 0x07, 0x02, 0x02, 0x30, 0x21, 0x30, 0x12,
        0x16, 0x05, 0x4d, 0x79, 0x4f, 0x72, 0x67, 0x30, 0x09, 0x02, 0x01, 0x01,
        0x02, 0x01, 0x02, 0x02, 0x01, 0x03, 0x1a, 0x0b, 0x48, 0x65, 0x6c, 0x6c,
        0x6f, 0x20, 0x57, 0x6f, 0x72, 0x6c, 0x64}},
  };
  for (const auto &t : kTests) {
    SCOPED_TRACE(t.name);
    SCOPED_TRACE(t.value);
    SCOPED_TRACE(t.conf);

    UniquePtr<CONF> conf;
    if (t.conf != nullptr) {
      conf.reset(NCONF_new(nullptr));
      ASSERT_TRUE(conf);
      UniquePtr<BIO> bio(BIO_new_mem_buf(t.conf, strlen(t.conf)));
      ASSERT_TRUE(bio);
      long error_line;
      ASSERT_TRUE(NCONF_load_bio(conf.get(), bio.get(), &error_line))
          << "Failed to load config at line " << error_line;
    }

    UniquePtr<X509_EXTENSION> ext(
        X509V3_EXT_nconf(conf.get(), nullptr, t.name, t.value.c_str()));
    if (t.expected.empty()) {
      EXPECT_FALSE(ext);
      ERR_clear_error();
    } else {
      ASSERT_TRUE(ext);
      uint8_t *der = nullptr;
      int len = i2d_X509_EXTENSION(ext.get(), &der);
      ASSERT_GE(len, 0);
      UniquePtr<uint8_t> free_der(der);
      EXPECT_EQ(Bytes(t.expected), Bytes(der, len));
    }

    // Repeat the test with an explicit `X509V3_CTX`.
    X509V3_CTX ctx;
    X509V3_set_ctx(&ctx, nullptr, nullptr, nullptr, nullptr, 0);
    X509V3_set_nconf(&ctx, conf.get());
    ext.reset(X509V3_EXT_nconf(conf.get(), &ctx, t.name, t.value.c_str()));
    if (t.expected.empty()) {
      EXPECT_FALSE(ext);
      ERR_clear_error();
    } else {
      ASSERT_TRUE(ext);
      uint8_t *der = nullptr;
      int len = i2d_X509_EXTENSION(ext.get(), &der);
      ASSERT_GE(len, 0);
      UniquePtr<uint8_t> free_der(der);
      EXPECT_EQ(Bytes(t.expected), Bytes(der, len));
    }
  }

  UniquePtr<EVP_PKEY> issuer_key = PrivateKeyFromPEM(kP256Key);
  ASSERT_TRUE(issuer_key);

  // Issuer cert without SKID.
  UniquePtr<X509> issuer_no_skid =
      MakeTestCert("Issuer", "Issuer", issuer_key.get(), /*is_ca=*/true);
  ASSERT_TRUE(issuer_no_skid);
  ASSERT_TRUE(X509_sign(issuer_no_skid.get(), issuer_key.get(), EVP_sha256()));

  // Issuer cert with SKID.
  UniquePtr<X509> issuer_with_skid =
      MakeTestCert("Issuer", "Issuer", issuer_key.get(), /*is_ca=*/true);
  ASSERT_TRUE(issuer_with_skid);
  static const uint8_t kSKID[] = {1, 2, 3, 4, 5, 6, 7, 8};
  ASSERT_TRUE(AddSubjectKeyIdentifier(issuer_with_skid.get(), kSKID));
  ASSERT_TRUE(
      X509_sign(issuer_with_skid.get(), issuer_key.get(), EVP_sha256()));

  // Issuer cert with an unparseable SKID extension.
  UniquePtr<X509> issuer_invalid_skid =
      MakeTestCert("Issuer", "Issuer", issuer_key.get(), /*is_ca=*/true);
  ASSERT_TRUE(issuer_invalid_skid);
  UniquePtr<X509_EXTENSION> invalid_skid(X509_EXTENSION_new());
  ASSERT_TRUE(X509_EXTENSION_set_object(
      invalid_skid.get(), OBJ_nid2obj(NID_subject_key_identifier)));
  ASSERT_TRUE(
      X509_add_ext(issuer_invalid_skid.get(), invalid_skid.get(), /*loc=*/-1));
  ASSERT_TRUE(
      X509_sign(issuer_invalid_skid.get(), issuer_key.get(), EVP_sha256()));

  const struct {
    const char *name;
    const char *value;
    // issuer_cert is the issuer certificate that must be used with the
    // extension.
    const X509 *issuer_cert;
    // expected is the resulting extension, encoded in DER, or the empty string
    // if an error is expected.
    std::vector<uint8_t> expected;
  } kTestsWithIssuer[] = {
      // The AKID extension is a series of options. The "keyid" option picks up
      // the issuer's SKID, but only if it is present.
      {"authorityKeyIdentifier",
       "keyid",
       issuer_no_skid.get(),
       {0x30, 0x09, 0x06, 0x03, 0x55, 0x1d, 0x23, 0x04, 0x02, 0x30, 0x00}},
      {"authorityKeyIdentifier",
       "keyid",
       issuer_with_skid.get(),
       {0x30, 0x13, 0x06, 0x03, 0x55, 0x1d, 0x23, 0x04, 0x0c, 0x30, 0x0a,
        0x80, 0x08, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08}},

      // The SKID extension could not be parsed.
      {"authorityKeyIdentifier", "keyid", issuer_invalid_skid.get(), {}},

      // keyid:always makes it an error when there is no issuer SKID.
      {"authorityKeyIdentifier", "keyid:always", issuer_no_skid.get(), {}},
      {"authorityKeyIdentifier",
       "keyid:always",
       issuer_with_skid.get(),
       {0x30, 0x13, 0x06, 0x03, 0x55, 0x1d, 0x23, 0x04, 0x0c, 0x30, 0x0a,
        0x80, 0x08, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08}},

      // The issuer option picks up the issuer's issuer and serial.
      {"authorityKeyIdentifier",
       "issuer",
       issuer_no_skid.get(),
       {0x30, 0x23, 0x06, 0x03, 0x55, 0x1d, 0x23, 0x04, 0x1c, 0x30,
        0x1a, 0xa1, 0x15, 0xa4, 0x13, 0x30, 0x11, 0x31, 0x0f, 0x30,
        0x0d, 0x06, 0x03, 0x55, 0x04, 0x03, 0x0c, 0x06, 0x49, 0x73,
        0x73, 0x75, 0x65, 0x72, 0x82, 0x01, 0x2a}},

      // If both options are enabled, the issuer option only applies if the
      // keyid option missed.
      {"authorityKeyIdentifier",
       "keyid,issuer",
       issuer_no_skid.get(),
       {0x30, 0x23, 0x06, 0x03, 0x55, 0x1d, 0x23, 0x04, 0x1c, 0x30,
        0x1a, 0xa1, 0x15, 0xa4, 0x13, 0x30, 0x11, 0x31, 0x0f, 0x30,
        0x0d, 0x06, 0x03, 0x55, 0x04, 0x03, 0x0c, 0x06, 0x49, 0x73,
        0x73, 0x75, 0x65, 0x72, 0x82, 0x01, 0x2a}},
      {"authorityKeyIdentifier",
       "keyid,issuer",
       issuer_with_skid.get(),
       {0x30, 0x13, 0x06, 0x03, 0x55, 0x1d, 0x23, 0x04, 0x0c, 0x30, 0x0a,
        0x80, 0x08, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08}},

      // Unless issuer:always is set, in which case both are included.
      {"authorityKeyIdentifier",
       "keyid,issuer:always",
       issuer_with_skid.get(),
       {0x30, 0x2d, 0x06, 0x03, 0x55, 0x1d, 0x23, 0x04, 0x26, 0x30, 0x24, 0x80,
        0x08, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0xa1, 0x15, 0xa4,
        0x13, 0x30, 0x11, 0x31, 0x0f, 0x30, 0x0d, 0x06, 0x03, 0x55, 0x04, 0x03,
        0x0c, 0x06, 0x49, 0x73, 0x73, 0x75, 0x65, 0x72, 0x82, 0x01, 0x2a}},

      // Invalid options are rejected.
      {"authorityKeyIdentifier", "keyid,badopt", issuer_with_skid.get(), {}},
  };
  for (const auto &t : kTestsWithIssuer) {
    SCOPED_TRACE(t.name);
    SCOPED_TRACE(t.value);

    X509V3_CTX ctx;
    X509V3_set_ctx(&ctx, t.issuer_cert, nullptr, nullptr, nullptr, 0);
    UniquePtr<X509_EXTENSION> ext(
        X509V3_EXT_nconf(nullptr, &ctx, t.name, t.value));
    if (t.expected.empty()) {
      EXPECT_FALSE(ext);
      ERR_clear_error();
    } else {
      ASSERT_TRUE(ext);
      uint8_t *der = nullptr;
      int len = i2d_X509_EXTENSION(ext.get(), &der);
      ASSERT_GE(len, 0);
      UniquePtr<uint8_t> free_der(der);
      EXPECT_EQ(Bytes(t.expected), Bytes(der, len));
    }
  }
}

TEST(X509Test, AddUnserializableExtension) {
  UniquePtr<EVP_PKEY> key = PrivateKeyFromPEM(kP256Key);
  ASSERT_TRUE(key);
  UniquePtr<X509> x509 =
      MakeTestCert("Issuer", "Subject", key.get(), /*is_ca=*/true);
  ASSERT_TRUE(x509);
  UniquePtr<X509_EXTENSION> ext(X509_EXTENSION_new());
  ASSERT_TRUE(X509_EXTENSION_set_object(ext.get(), OBJ_get_undef()));
  EXPECT_FALSE(X509_add_ext(x509.get(), ext.get(), /*loc=*/-1));
}

// Test that, when constructing an `X509_NAME`, names are sorted by DER order.
TEST(X509Test, SortRDN) {
  UniquePtr<X509_NAME> name(X509_NAME_new());
  ASSERT_TRUE(name);

  auto append_entry_new_rdn = [&](const char *str) {
    return X509_NAME_add_entry_by_NID(name.get(), NID_commonName, MBSTRING_ASC,
                                      reinterpret_cast<const uint8_t *>(str),
                                      strlen(str), /*loc=*/-1, /*set=*/0);
  };
  auto append_entry_prev_rdn = [&](const char *str) {
    return X509_NAME_add_entry_by_NID(name.get(), NID_commonName, MBSTRING_ASC,
                                      reinterpret_cast<const uint8_t *>(str),
                                      strlen(str), /*loc=*/-1, /*set=*/-1);
  };

  // This is the sort order to expect.
  ASSERT_TRUE(append_entry_new_rdn("A"));
  ASSERT_TRUE(append_entry_prev_rdn("B"));
  ASSERT_TRUE(append_entry_prev_rdn("AA"));
  ASSERT_TRUE(append_entry_prev_rdn("AB"));

  // The same RDN, with entries added in a different order.
  ASSERT_TRUE(append_entry_new_rdn("AB"));
  ASSERT_TRUE(append_entry_prev_rdn("AA"));
  ASSERT_TRUE(append_entry_prev_rdn("B"));
  ASSERT_TRUE(append_entry_prev_rdn("A"));

  // The same RDN, with entries added in a different order.
  ASSERT_TRUE(append_entry_new_rdn("A"));
  ASSERT_TRUE(append_entry_prev_rdn("AA"));
  ASSERT_TRUE(append_entry_prev_rdn("B"));
  ASSERT_TRUE(append_entry_prev_rdn("AB"));

  uint8_t *der = nullptr;
  int der_len = i2d_X509_NAME(name.get(), &der);
  ASSERT_GT(der_len, 0);
  UniquePtr<uint8_t> free_der(der);

  // SEQUENCE {
  //   SET {
  //     SEQUENCE {
  //       # commonName
  //       OBJECT_IDENTIFIER { 2.5.4.3 }
  //       UTF8String { "A" }
  //     }
  //     SEQUENCE {
  //       # commonName
  //       OBJECT_IDENTIFIER { 2.5.4.3 }
  //       UTF8String { "B" }
  //     }
  //     SEQUENCE {
  //       # commonName
  //       OBJECT_IDENTIFIER { 2.5.4.3 }
  //       UTF8String { "AA" }
  //     }
  //     SEQUENCE {
  //       # commonName
  //       OBJECT_IDENTIFIER { 2.5.4.3 }
  //       UTF8String { "AB" }
  //     }
  //   }
  //   ...two more copies of the above SET...
  // }
  static uint8_t kExpected[] = {
      0x30, 0x81, 0x84, 0x31, 0x2a, 0x30, 0x08, 0x06, 0x03, 0x55, 0x04, 0x03,
      0x0c, 0x01, 0x41, 0x30, 0x08, 0x06, 0x03, 0x55, 0x04, 0x03, 0x0c, 0x01,
      0x42, 0x30, 0x09, 0x06, 0x03, 0x55, 0x04, 0x03, 0x0c, 0x02, 0x41, 0x41,
      0x30, 0x09, 0x06, 0x03, 0x55, 0x04, 0x03, 0x0c, 0x02, 0x41, 0x42, 0x31,
      0x2a, 0x30, 0x08, 0x06, 0x03, 0x55, 0x04, 0x03, 0x0c, 0x01, 0x41, 0x30,
      0x08, 0x06, 0x03, 0x55, 0x04, 0x03, 0x0c, 0x01, 0x42, 0x30, 0x09, 0x06,
      0x03, 0x55, 0x04, 0x03, 0x0c, 0x02, 0x41, 0x41, 0x30, 0x09, 0x06, 0x03,
      0x55, 0x04, 0x03, 0x0c, 0x02, 0x41, 0x42, 0x31, 0x2a, 0x30, 0x08, 0x06,
      0x03, 0x55, 0x04, 0x03, 0x0c, 0x01, 0x41, 0x30, 0x08, 0x06, 0x03, 0x55,
      0x04, 0x03, 0x0c, 0x01, 0x42, 0x30, 0x09, 0x06, 0x03, 0x55, 0x04, 0x03,
      0x0c, 0x02, 0x41, 0x41, 0x30, 0x09, 0x06, 0x03, 0x55, 0x04, 0x03, 0x0c,
      0x02, 0x41, 0x42};
  EXPECT_EQ(Bytes(kExpected), Bytes(der, der_len));
}

TEST(X509Test, NameAttributeValues) {
  // 1.2.840.113554.4.1.72585.0. We use an unrecognized OID because using an
  // arbitrary ASN.1 type as the value for commonName is invalid. Our parser
  // does not check this, but best to avoid unrelated errors in tests, in case
  // we decide to later.
  static const uint8_t kOID[] = {0x2a, 0x86, 0x48, 0x86, 0xf7, 0x12,
                                 0x04, 0x01, 0x84, 0xb7, 0x09, 0x00};
  static const char kOIDText[] = "1.2.840.113554.4.1.72585.0";

  auto encode_single_attribute_name =
      [](CBS_ASN1_TAG tag, std::string_view contents) -> std::vector<uint8_t> {
    auto bytes = StringAsBytes(contents);
    ScopedCBB cbb;
    CBB seq, rdn, attr;
    if (!CBB_init(cbb.get(), 128) ||
        !CBB_add_asn1(cbb.get(), &seq, CBS_ASN1_SEQUENCE) ||
        !CBB_add_asn1(&seq, &rdn, CBS_ASN1_SET) ||
        !CBB_add_asn1(&rdn, &attr, CBS_ASN1_SEQUENCE) ||
        !CBB_add_asn1_element(&attr, CBS_ASN1_OBJECT, kOID, sizeof(kOID)) ||
        !CBB_add_asn1_element(&attr, tag, bytes.data(), bytes.size()) ||
        !CBB_flush(cbb.get())) {
      ADD_FAILURE() << "Could not encode name";
      return {};
    };
    return std::vector<uint8_t>(CBB_data(cbb.get()),
                                CBB_data(cbb.get()) + CBB_len(cbb.get()));
  };

  const struct {
    CBS_ASN1_TAG der_tag;
    std::string der_contents;
    int str_type;
    std::string str_contents;
  } kTests[] = {
      // String types are parsed as string types.
      {CBS_ASN1_BITSTRING, std::string("\0", 1), V_ASN1_BIT_STRING, ""},
      {CBS_ASN1_UTF8STRING, "abc", V_ASN1_UTF8STRING, "abc"},
      {CBS_ASN1_NUMERICSTRING, "123", V_ASN1_NUMERICSTRING, "123"},
      {CBS_ASN1_PRINTABLESTRING, "abc", V_ASN1_PRINTABLESTRING, "abc"},
      {CBS_ASN1_T61STRING, "abc", V_ASN1_T61STRING, "abc"},
      {CBS_ASN1_IA5STRING, "abc", V_ASN1_IA5STRING, "abc"},
      {CBS_ASN1_UNIVERSALSTRING, std::string("\0\0\0a", 4),
       V_ASN1_UNIVERSALSTRING, std::string("\0\0\0a", 4)},
      {CBS_ASN1_BMPSTRING, std::string("\0a", 2), V_ASN1_BMPSTRING,
       std::string("\0a", 2)},
      {CBS_ASN1_OCTETSTRING, "abc", V_ASN1_OCTET_STRING, "abc"},
      {CBS_ASN1_UTCTIME, "700101000000Z", V_ASN1_UTCTIME, "700101000000Z"},
      {CBS_ASN1_GENERALIZEDTIME, "19700101000000Z", V_ASN1_GENERALIZEDTIME,
       "19700101000000Z"},

      // ENUMERATED is supported but, currently, INTEGER is not.
      {CBS_ASN1_INTEGER, "\x01", V_ASN1_INTEGER, "\x01"},
      {CBS_ASN1_ENUMERATED, "\x01", V_ASN1_ENUMERATED, "\x01"},

      // Test negative values. These are interesting because, when encoding, the
      // ASN.1 type must be determined from the string type, but the string type
      // has an extra `V_ASN1_NEG` bit.
      {CBS_ASN1_INTEGER, "\xff", V_ASN1_NEG_INTEGER, "\x01"},
      {CBS_ASN1_ENUMERATED, "\xff", V_ASN1_NEG_ENUMERATED, "\x01"},

      // SEQUENCE and SET use their `ASN1_STRING` representation, which includes
      // the tag and length.
      {CBS_ASN1_SEQUENCE, "", V_ASN1_SEQUENCE, std::string("\x30\x00", 2)},
      {CBS_ASN1_SET, "", V_ASN1_SET, std::string("\x31\x00", 2)},

      // NULL, BOOLEAN, and OBJECT IDENTIFIER use non-`ASN1_STRING`
      // representations, so they are represented with `V_ASN1_OTHER`.
      {CBS_ASN1_NULL, "", V_ASN1_OTHER, std::string("\x05\x00", 2)},
      {CBS_ASN1_BOOLEAN, std::string("\x00", 1), V_ASN1_OTHER,
       std::string("\x01\x01\x00", 3)},
      {CBS_ASN1_BOOLEAN, "\xff", V_ASN1_OTHER, "\x01\x01\xff"},
      {CBS_ASN1_OBJECT, "\x01\x02\x03\x04", V_ASN1_OTHER,
       "\x06\x04\x01\x02\x03\x04"},

      // These types are not actually supported by the library, but we accept
      // them as `V_ASN1_OTHER`.
      {7 /* ObjectDescriptor */, "", V_ASN1_OTHER, std::string("\x07\x00", 2)},
      {CBS_ASN1_CONSTRUCTED | 8 /* EXTERNAL */, "", V_ASN1_OTHER,
       std::string("\x28\x00", 2)},
      {9 /* REAL */, "", V_ASN1_OTHER, std::string("\x09\x00", 2)},
      {CBS_ASN1_CONSTRUCTED | 11 /* EMBEDDED PDV */, "", V_ASN1_OTHER,
       std::string("\x2b\x00", 2)},
      {13 /* RELATIVE-OID */, "\x01", V_ASN1_OTHER, "\x0d\x01\x01"},
      {14 /* TIME */, "", V_ASN1_OTHER, std::string("\x0e\x00", 2)},
      {15 /* not a type; reserved value */, "", V_ASN1_OTHER,
       std::string("\x0f\x00", 2)},
      {CBS_ASN1_CONSTRUCTED | 29 /* CHARACTER STRING */, "", V_ASN1_OTHER,
       std::string("\x3d\x00", 2)},

      // Non-universal tags are allowed as `V_ASN1_OTHER` too.
      {CBS_ASN1_APPLICATION | CBS_ASN1_CONSTRUCTED | 42, "", V_ASN1_OTHER,
       std::string("\x7f\x2a\x00", 3)},
      {CBS_ASN1_APPLICATION | 42, "", V_ASN1_OTHER,
       std::string("\x5f\x2a\x00", 3)},
  };
  for (const auto &t : kTests) {
    SCOPED_TRACE(t.der_tag);
    SCOPED_TRACE(Bytes(t.der_contents));

    // Construct an X.509 name containing a single RDN with a single attribute:
    // kOID with the specified value.
    auto encoded = encode_single_attribute_name(t.der_tag, t.der_contents);
    ASSERT_FALSE(encoded.empty());
    SCOPED_TRACE(Bytes(encoded));

    // The input should parse.
    const uint8_t *inp = encoded.data();
    UniquePtr<X509_NAME> name(d2i_X509_NAME(nullptr, &inp, encoded.size()));
    ASSERT_TRUE(name);
    EXPECT_EQ(inp, encoded.data() + encoded.size())
        << "input was not fully consumed";

    // Check there is a single attribute with the expected in-memory
    // representation.
    ASSERT_EQ(1, X509_NAME_entry_count(name.get()));
    const X509_NAME_ENTRY *entry = X509_NAME_get_entry(name.get(), 0);
    const ASN1_OBJECT *obj = X509_NAME_ENTRY_get_object(entry);
    EXPECT_EQ(Bytes(OBJ_get0_data(obj), OBJ_length(obj)), Bytes(kOID));
    const ASN1_STRING *value = X509_NAME_ENTRY_get_data(entry);
    EXPECT_EQ(ASN1_STRING_type(value), t.str_type);
    EXPECT_EQ(Bytes(ASN1StringAsBytes(value)), Bytes(t.str_contents));

    // The name should re-encode with the same input.
    uint8_t *der = nullptr;
    int der_len = i2d_X509_NAME(name.get(), &der);
    ASSERT_GE(der_len, 0);
    UniquePtr<uint8_t> free_der(der);
    EXPECT_EQ(Bytes(der, der_len), Bytes(encoded));

    // X509_NAME internally caches its encoding, which means the check above
    // does not fully test re-encoding. Repeat the test by constructing an
    // `X509_NAME` from the string representation.
    name.reset(X509_NAME_new());
    ASSERT_TRUE(name);
    ASSERT_TRUE(X509_NAME_add_entry_by_txt(
        name.get(), kOIDText, t.str_type,
        reinterpret_cast<const uint8_t *>(t.str_contents.data()),
        t.str_contents.size(), /*loc=*/-1, /*set=*/0));

    // The name should re-encode with the same input.
    der = nullptr;
    der_len = i2d_X509_NAME(name.get(), &der);
    ASSERT_GE(der_len, 0);
    free_der.reset(der);
    EXPECT_EQ(Bytes(der, der_len), Bytes(encoded));
  }

  const struct {
    CBS_ASN1_TAG der_tag;
    std::string der_contents;
  } kInvalidTests[] = {
      // Errors in supported universal types should be handled.
      {CBS_ASN1_NULL, "not null"},
      {CBS_ASN1_BOOLEAN, "not bool"},
      {CBS_ASN1_BOOLEAN, "\1"},  // BOOL in DER must be 0x00 or 0xff.
      {CBS_ASN1_OBJECT, ""},
      {CBS_ASN1_OBJECT, "\x80\x01"},  // Non-minimal OID encoding
      {CBS_ASN1_INTEGER, std::string("\0\0", 2)},
      {CBS_ASN1_ENUMERATED, std::string("\0\0", 2)},
      {CBS_ASN1_BITSTRING, ""},
      {CBS_ASN1_UTF8STRING, "not utf-8 \xff"},
      {CBS_ASN1_BMPSTRING, "not utf-16 "},
      {CBS_ASN1_UNIVERSALSTRING, "not utf-32"},
      {CBS_ASN1_UTCTIME, "not utctime"},
      {CBS_ASN1_GENERALIZEDTIME, "not generalizedtime"},
      {CBS_ASN1_NULL | CBS_ASN1_CONSTRUCTED, ""},
      {CBS_ASN1_OBJECT | CBS_ASN1_CONSTRUCTED, "\x01\x02\x03\x04"},
      {CBS_ASN1_BOOLEAN | CBS_ASN1_CONSTRUCTED, "\xff"},
      {CBS_ASN1_UTF8STRING | CBS_ASN1_CONSTRUCTED, ""},
      {CBS_ASN1_SEQUENCE & ~CBS_ASN1_CONSTRUCTED, ""},
  };
  for (const auto &t : kInvalidTests) {
    SCOPED_TRACE(t.der_tag);
    SCOPED_TRACE(Bytes(t.der_contents));

    // Construct an X.509 name containing a single RDN with a single attribute:
    // kOID with the specified value.
    auto encoded = encode_single_attribute_name(t.der_tag, t.der_contents);
    ASSERT_FALSE(encoded.empty());
    SCOPED_TRACE(Bytes(encoded));

    // The input should not parse.
    const uint8_t *inp = encoded.data();
    UniquePtr<X509_NAME> name(d2i_X509_NAME(nullptr, &inp, encoded.size()));
    EXPECT_FALSE(name);
    EXPECT_TRUE(ErrorsAreAndClear({{ERR_LIB_ASN1, std::nullopt}}));
  }
}

TEST(X509Test, GetTextByOBJ) {
  struct OBJTestCase {
    const char *content;
    int content_type;
    int len;
    int expected_result;
    const char *expected_string;
  } kTests[] = {
      {"", V_ASN1_UTF8STRING, 0, 0, ""},
      {"derp", V_ASN1_UTF8STRING, 4, 4, "derp"},
      {"\x30\x00",  // Empty sequence can not be converted to UTF-8
       V_ASN1_SEQUENCE, 2, -1, ""},
      {
          "der\0p",
          V_ASN1_TELETEXSTRING,
          5,
          -1,
          "",
      },
      {
          "0123456789ABCDEF",
          V_ASN1_IA5STRING,
          16,
          16,
          "0123456789ABCDEF",
      },
      {
          "\x07\xff",
          V_ASN1_BMPSTRING,
          2,
          2,
          "\xdf\xbf",
      },
      {
          "\x00\xc3\x00\xaf",
          V_ASN1_BMPSTRING,
          4,
          4,
          "\xc3\x83\xc2\xaf",
      },
  };
  for (const auto &test : kTests) {
    UniquePtr<X509_NAME> name(X509_NAME_new());
    ASSERT_TRUE(name);
    ASSERT_TRUE(X509_NAME_add_entry_by_NID(
        name.get(), NID_commonName, test.content_type,
        reinterpret_cast<const uint8_t *>(test.content), test.len, /*loc=*/-1,
        /*set=*/0));
    char text[256] = {};
    EXPECT_EQ(test.expected_result,
              X509_NAME_get_text_by_NID(name.get(), NID_commonName, text,
                                        sizeof(text)));
    EXPECT_STREQ(text, test.expected_string);
    if (test.expected_result > 0) {
      // Test truncation. The function writes a trailing NUL byte so the
      // buffer needs to be one bigger than the expected result.
      char small[2] = "a";
      EXPECT_EQ(
          -1, X509_NAME_get_text_by_NID(name.get(), NID_commonName, small, 1));
      // The buffer should be unmodified by truncation failure.
      EXPECT_STREQ(small, "a");
    }
  }
}

TEST(X509Test, ParamInheritance) {
  // `X509_VERIFY_PARAM_inherit` with both unset.
  {
    UniquePtr<X509_VERIFY_PARAM> dest(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(dest);
    UniquePtr<X509_VERIFY_PARAM> src(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(src);
    ASSERT_TRUE(X509_VERIFY_PARAM_inherit(dest.get(), src.get()));
    EXPECT_EQ(X509_VERIFY_PARAM_get_depth(dest.get()), -1);
  }

  // `X509_VERIFY_PARAM_inherit` with source set.
  {
    UniquePtr<X509_VERIFY_PARAM> dest(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(dest);
    UniquePtr<X509_VERIFY_PARAM> src(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(src);
    X509_VERIFY_PARAM_set_depth(src.get(), 5);
    ASSERT_TRUE(X509_VERIFY_PARAM_inherit(dest.get(), src.get()));
    EXPECT_EQ(X509_VERIFY_PARAM_get_depth(dest.get()), 5);
  }

  // `X509_VERIFY_PARAM_inherit` with destination set.
  {
    UniquePtr<X509_VERIFY_PARAM> dest(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(dest);
    UniquePtr<X509_VERIFY_PARAM> src(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(src);
    X509_VERIFY_PARAM_set_depth(dest.get(), 5);
    ASSERT_TRUE(X509_VERIFY_PARAM_inherit(dest.get(), src.get()));
    EXPECT_EQ(X509_VERIFY_PARAM_get_depth(dest.get()), 5);
  }

  // `X509_VERIFY_PARAM_inherit` with both set.
  {
    UniquePtr<X509_VERIFY_PARAM> dest(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(dest);
    UniquePtr<X509_VERIFY_PARAM> src(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(src);
    X509_VERIFY_PARAM_set_depth(dest.get(), 5);
    X509_VERIFY_PARAM_set_depth(src.get(), 10);
    ASSERT_TRUE(X509_VERIFY_PARAM_inherit(dest.get(), src.get()));
    // The existing value is used.
    EXPECT_EQ(X509_VERIFY_PARAM_get_depth(dest.get()), 5);
  }

  // `X509_VERIFY_PARAM_set1` with both unset.
  {
    UniquePtr<X509_VERIFY_PARAM> dest(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(dest);
    UniquePtr<X509_VERIFY_PARAM> src(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(src);
    ASSERT_TRUE(X509_VERIFY_PARAM_set1(dest.get(), src.get()));
    EXPECT_EQ(X509_VERIFY_PARAM_get_depth(dest.get()), -1);
  }

  // `X509_VERIFY_PARAM_set1` with source set.
  {
    UniquePtr<X509_VERIFY_PARAM> dest(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(dest);
    UniquePtr<X509_VERIFY_PARAM> src(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(src);
    X509_VERIFY_PARAM_set_depth(src.get(), 5);
    ASSERT_TRUE(X509_VERIFY_PARAM_set1(dest.get(), src.get()));
    EXPECT_EQ(X509_VERIFY_PARAM_get_depth(dest.get()), 5);
  }

  // `X509_VERIFY_PARAM_set1` with destination set.
  {
    UniquePtr<X509_VERIFY_PARAM> dest(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(dest);
    UniquePtr<X509_VERIFY_PARAM> src(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(src);
    X509_VERIFY_PARAM_set_depth(dest.get(), 5);
    ASSERT_TRUE(X509_VERIFY_PARAM_set1(dest.get(), src.get()));
    EXPECT_EQ(X509_VERIFY_PARAM_get_depth(dest.get()), 5);
  }

  // `X509_VERIFY_PARAM_set1` with both set.
  {
    UniquePtr<X509_VERIFY_PARAM> dest(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(dest);
    UniquePtr<X509_VERIFY_PARAM> src(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(src);
    X509_VERIFY_PARAM_set_depth(dest.get(), 5);
    X509_VERIFY_PARAM_set_depth(src.get(), 10);
    ASSERT_TRUE(X509_VERIFY_PARAM_set1(dest.get(), src.get()));
    // The new value is used.
    EXPECT_EQ(X509_VERIFY_PARAM_get_depth(dest.get()), 10);
  }

  // `X509_VERIFY_PARAM_inherit` and `X509_VERIFY_PARAM_set1` must fail if the
  // source parameter is poisoned.
  {
    UniquePtr<X509_VERIFY_PARAM> dest(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(dest);
    UniquePtr<X509_VERIFY_PARAM> src(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(src);

    // Poison the source parameter (using an embedded NUL in hostname).
    ASSERT_FALSE(X509_VERIFY_PARAM_set1_host(src.get(), "a", 2));

    EXPECT_FALSE(X509_VERIFY_PARAM_inherit(dest.get(), src.get()));
    EXPECT_FALSE(X509_VERIFY_PARAM_set1(dest.get(), src.get()));
  }

  // `X509_VERIFY_PARAM_inherit` and `X509_VERIFY_PARAM_set1` must fail if the
  // destination parameter is poisoned.
  {
    UniquePtr<X509_VERIFY_PARAM> dest(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(dest);
    UniquePtr<X509_VERIFY_PARAM> src(X509_VERIFY_PARAM_new());
    ASSERT_TRUE(src);

    // Poison the destination parameter (using an embedded NUL in hostname).
    ASSERT_FALSE(X509_VERIFY_PARAM_set1_host(dest.get(), "a", 2));

    EXPECT_FALSE(X509_VERIFY_PARAM_inherit(dest.get(), src.get()));
    EXPECT_FALSE(X509_VERIFY_PARAM_set1(dest.get(), src.get()));
  }
}

TEST(X509Test, PublicKeyCache) {
  UniquePtr<EVP_PKEY> key = PrivateKeyFromPEM(kP256Key);
  ASSERT_TRUE(key);

  X509_PUBKEY *pub = nullptr;
  ASSERT_TRUE(X509_PUBKEY_set(&pub, key.get()));
  UniquePtr<X509_PUBKEY> free_pub(pub);

  UniquePtr<EVP_PKEY> key2(X509_PUBKEY_get(pub));
  ASSERT_TRUE(key2);
  EXPECT_EQ(1, EVP_PKEY_eq(key.get(), key2.get()));

  // Replace `pub` with different (garbage) values.
  ASSERT_TRUE(X509_PUBKEY_set0_param(pub, OBJ_nid2obj(NID_subject_alt_name),
                                     V_ASN1_NULL, nullptr, nullptr, 0));

  // The cached key should no longer be returned.
  key2.reset(X509_PUBKEY_get(pub));
  EXPECT_FALSE(key2);
}

// Tests some unusual behavior in `X509_STORE_CTX_set_purpose` and
// `X509_STORE_CTX_set_trust`.
TEST(X509Test, ContextTrustAndPurpose) {
  UniquePtr<X509_STORE> store(X509_STORE_new());
  ASSERT_TRUE(store);
  UniquePtr<X509> leaf(CertFromPEM(kLeafPEM));
  ASSERT_TRUE(leaf);

  UniquePtr<X509_STORE_CTX> ctx(X509_STORE_CTX_new());
  ASSERT_TRUE(ctx);
  ASSERT_TRUE(X509_STORE_CTX_init(ctx.get(), store.get(), leaf.get(), nullptr));

  // Initially, neither parameter is set.
  EXPECT_EQ(ctx->param->purpose, 0);
  EXPECT_EQ(ctx->param->trust, 0);

  // Invalid purpose and trust types fail.
  EXPECT_FALSE(X509_STORE_CTX_set_purpose(ctx.get(), 999));
  EXPECT_FALSE(X509_STORE_CTX_set_trust(ctx.get(), 999));

  // It is not possible to set `X509_PURPOSE_ANY` with this API, because there
  // is no corresponding trust.
  EXPECT_FALSE(X509_STORE_CTX_set_purpose(ctx.get(), X509_PURPOSE_ANY));

  // Setting a purpose also sets the corresponding trust.
  ASSERT_TRUE(X509_STORE_CTX_set_purpose(ctx.get(), X509_PURPOSE_SSL_SERVER));
  EXPECT_EQ(ctx->param->purpose, X509_PURPOSE_SSL_SERVER);
  EXPECT_EQ(ctx->param->trust, X509_TRUST_SSL_SERVER);

  // Once set, the functions silently do nothing.
  ASSERT_TRUE(X509_STORE_CTX_set_purpose(ctx.get(), X509_PURPOSE_SSL_CLIENT));
  ASSERT_TRUE(X509_STORE_CTX_set_trust(ctx.get(), X509_TRUST_SSL_CLIENT));
  EXPECT_EQ(ctx->param->purpose, X509_PURPOSE_SSL_SERVER);
  EXPECT_EQ(ctx->param->trust, X509_TRUST_SSL_SERVER);

  // Start over.
  ctx.reset(X509_STORE_CTX_new());
  ASSERT_TRUE(ctx);
  ASSERT_TRUE(X509_STORE_CTX_init(ctx.get(), store.get(), leaf.get(), nullptr));
  EXPECT_EQ(ctx->param->purpose, 0);
  EXPECT_EQ(ctx->param->trust, 0);

  // Setting trust leaves purpose unset.
  ASSERT_TRUE(X509_STORE_CTX_set_trust(ctx.get(), X509_TRUST_SSL_SERVER));
  EXPECT_EQ(ctx->param->purpose, 0);
  EXPECT_EQ(ctx->param->trust, X509_TRUST_SSL_SERVER);

  // If trust is set, but not purpose, `X509_STORE_CTX_set_purpose` only sets
  // purpose.
  ASSERT_TRUE(X509_STORE_CTX_set_purpose(ctx.get(), X509_PURPOSE_SSL_CLIENT));
  EXPECT_EQ(ctx->param->purpose, X509_PURPOSE_SSL_CLIENT);
  EXPECT_EQ(ctx->param->trust, X509_TRUST_SSL_SERVER);

  // Start over.
  ctx.reset(X509_STORE_CTX_new());
  ASSERT_TRUE(ctx);
  ASSERT_TRUE(X509_STORE_CTX_init(ctx.get(), store.get(), leaf.get(), nullptr));
  EXPECT_EQ(ctx->param->purpose, 0);
  EXPECT_EQ(ctx->param->trust, 0);

  // If purpose is set, but not trust, `X509_STORE_CTX_set_purpose` only sets
  // trust.
  ASSERT_TRUE(X509_VERIFY_PARAM_set_purpose(
      X509_STORE_CTX_get0_param(ctx.get()), X509_PURPOSE_SSL_CLIENT));
  EXPECT_EQ(ctx->param->purpose, X509_PURPOSE_SSL_CLIENT);
  EXPECT_EQ(ctx->param->trust, 0);

  ASSERT_TRUE(X509_STORE_CTX_set_purpose(ctx.get(), X509_PURPOSE_SSL_SERVER));
  EXPECT_EQ(ctx->param->purpose, X509_PURPOSE_SSL_CLIENT);
  EXPECT_EQ(ctx->param->trust, X509_TRUST_SSL_SERVER);
}

TEST(X509Test, Purpose) {
  UniquePtr<EVP_PKEY> key = PrivateKeyFromPEM(kP256Key);
  ASSERT_TRUE(key);

  struct {
    int purpose;
    int eku_nid;
    std::vector<KeyUsage> key_usages;
  } kTests[] = {
      {X509_PURPOSE_SSL_CLIENT,
       NID_client_auth,
       {KeyUsage::kDigitalSignature, KeyUsage::kKeyAgreement}},
      {X509_PURPOSE_SSL_SERVER,
       NID_server_auth,
       {KeyUsage::kDigitalSignature, KeyUsage::kKeyAgreement,
        KeyUsage::kKeyEncipherment}},
      {X509_PURPOSE_NS_SSL_SERVER,
       NID_server_auth,
       {KeyUsage::kKeyEncipherment}},
      {X509_PURPOSE_SMIME_SIGN,
       NID_email_protect,
       {KeyUsage::kDigitalSignature, KeyUsage::kNonRepudiation}},
      {X509_PURPOSE_SMIME_ENCRYPT,
       NID_email_protect,
       {KeyUsage::kKeyEncipherment}},
      {X509_PURPOSE_CRL_SIGN, NID_undef, {KeyUsage::kCRLSign}},
  };
  for (const auto &t : kTests) {
    SCOPED_TRACE(t.purpose);

    auto configure_callback = [&](X509_STORE_CTX *ctx) {
      X509_STORE_CTX_set_purpose(ctx, t.purpose);
    };

    // An unconstrained cert chain is valid.
    UniquePtr<X509> root =
        MakeTestCert("Root", "Root", key.get(), /*is_ca=*/true);
    ASSERT_TRUE(root);
    ASSERT_TRUE(X509_sign(root.get(), key.get(), EVP_sha256()));

    UniquePtr<X509> intermediate =
        MakeTestCert("Root", "Intermediate", key.get(), /*is_ca=*/true);
    ASSERT_TRUE(intermediate);
    ASSERT_TRUE(X509_sign(intermediate.get(), key.get(), EVP_sha256()));

    UniquePtr<X509> leaf =
        MakeTestCert("Intermediate", "Leaf", key.get(), /*is_ca=*/false);
    ASSERT_TRUE(leaf);
    ASSERT_TRUE(X509_sign(leaf.get(), key.get(), EVP_sha256()));

    EXPECT_EQ(X509_V_OK, Verify(leaf.get(), {root.get()}, {intermediate.get()},
                                {}, 0, configure_callback));

    // A leaf and intermediate with compatible constraints is valid.
    intermediate =
        MakeTestCert("Root", "Intermediate", key.get(), /*is_ca=*/true);
    ASSERT_TRUE(intermediate);
    ASSERT_TRUE(AddKeyUsage(intermediate.get(), {KeyUsage::kKeyCertSign}));
    if (t.eku_nid != NID_undef) {
      ASSERT_TRUE(AddExtendedKeyUsage(intermediate.get(), {t.eku_nid}));
    }
    ASSERT_TRUE(X509_sign(intermediate.get(), key.get(), EVP_sha256()));

    leaf = MakeTestCert("Intermediate", "Leaf", key.get(), /*is_ca=*/false);
    ASSERT_TRUE(leaf);
    if (t.eku_nid != NID_undef) {
      ASSERT_TRUE(AddExtendedKeyUsage(leaf.get(), {t.eku_nid}));
    }
    ASSERT_TRUE(AddKeyUsage(leaf.get(), t.key_usages));
    ASSERT_TRUE(X509_sign(leaf.get(), key.get(), EVP_sha256()));

    EXPECT_EQ(X509_V_OK, Verify(leaf.get(), {root.get()}, {intermediate.get()},
                                {}, 0, configure_callback));

    // Each key usage asserted individually is valid.
    for (KeyUsage usage : t.key_usages) {
      SCOPED_TRACE(static_cast<int>(usage));
      leaf = MakeTestCert("Intermediate", "Leaf", key.get(), /*is_ca=*/false);
      ASSERT_TRUE(leaf);
      if (t.eku_nid != NID_undef) {
        ASSERT_TRUE(AddExtendedKeyUsage(leaf.get(), {t.eku_nid}));
      }
      ASSERT_TRUE(AddKeyUsage(leaf.get(), {usage}));
      ASSERT_TRUE(X509_sign(leaf.get(), key.get(), EVP_sha256()));
      EXPECT_EQ(X509_V_OK,
                Verify(leaf.get(), {root.get()}, {intermediate.get()}, {}, 0,
                       configure_callback));
    }

    // A leaf with the wrong EKU is invalid.
    if (t.eku_nid != NID_undef) {
      leaf = MakeTestCert("Intermediate", "Leaf", key.get(), /*is_ca=*/false);
      ASSERT_TRUE(leaf);
      ASSERT_TRUE(AddExtendedKeyUsage(leaf.get(), {NID_rsaEncryption}));
      ASSERT_TRUE(AddKeyUsage(leaf.get(), t.key_usages));
      ASSERT_TRUE(X509_sign(leaf.get(), key.get(), EVP_sha256()));
      EXPECT_EQ(X509_V_ERR_INVALID_PURPOSE,
                Verify(leaf.get(), {root.get()}, {intermediate.get()}, {}, 0,
                       configure_callback));
    }

    // A leaf without any of the requested key usages is invalid.
    std::vector<KeyUsage> usages;
    for (int i = 0; i < 10; i++) {
      auto k = static_cast<KeyUsage>(i);
      if (std::find(t.key_usages.begin(), t.key_usages.end(), k) ==
          t.key_usages.end()) {
        usages.push_back(k);
      }
    }
    leaf = MakeTestCert("Intermediate", "Leaf", key.get(), /*is_ca=*/false);
    ASSERT_TRUE(leaf);
    if (t.eku_nid != NID_undef) {
      ASSERT_TRUE(AddExtendedKeyUsage(leaf.get(), {t.eku_nid}));
    }
    ASSERT_TRUE(AddKeyUsage(leaf.get(), usages));
    ASSERT_TRUE(X509_sign(leaf.get(), key.get(), EVP_sha256()));
    EXPECT_EQ(X509_V_ERR_INVALID_PURPOSE,
              Verify(leaf.get(), {root.get()}, {intermediate.get()}, {}, 0,
                     configure_callback));

    // Extra EKUs and key usages are fine.
    usages.clear();
    for (int i = 0; i < 10; i++) {
      usages.push_back(static_cast<KeyUsage>(i));
    }
    leaf = MakeTestCert("Intermediate", "Leaf", key.get(), /*is_ca=*/false);
    ASSERT_TRUE(leaf);
    if (t.eku_nid != NID_undef) {
      ASSERT_TRUE(
          AddExtendedKeyUsage(leaf.get(), {t.eku_nid, NID_rsaEncryption}));
    }
    ASSERT_TRUE(AddKeyUsage(leaf.get(), usages));
    ASSERT_TRUE(X509_sign(leaf.get(), key.get(), EVP_sha256()));
    EXPECT_EQ(X509_V_OK, Verify(leaf.get(), {root.get()}, {intermediate.get()},
                                {}, 0, configure_callback));

    // anyExtendedKeyUsage is not allowed in place of a concrete EKU.
    if (t.eku_nid != NID_undef) {
      leaf = MakeTestCert("Intermediate", "Leaf", key.get(), /*is_ca=*/false);
      ASSERT_TRUE(leaf);
      ASSERT_TRUE(AddExtendedKeyUsage(leaf.get(), {NID_anyExtendedKeyUsage}));
      ASSERT_TRUE(AddKeyUsage(leaf.get(), t.key_usages));
      ASSERT_TRUE(X509_sign(leaf.get(), key.get(), EVP_sha256()));
      EXPECT_EQ(X509_V_ERR_INVALID_PURPOSE,
                Verify(leaf.get(), {root.get()}, {intermediate.get()}, {}, 0,
                       configure_callback));
    }

    // Restore `leaf` to a valid option.
    leaf = MakeTestCert("Intermediate", "Leaf", key.get(), /*is_ca=*/false);
    ASSERT_TRUE(leaf);
    ASSERT_TRUE(X509_sign(leaf.get(), key.get(), EVP_sha256()));

    // The intermediate must have the keyCertSign bit. This bit is checked in
    // multiple places. The first place that fails is in looking for candidate
    // issuers.
    intermediate =
        MakeTestCert("Root", "Intermediate", key.get(), /*is_ca=*/true);
    ASSERT_TRUE(intermediate);
    ASSERT_TRUE(AddKeyUsage(intermediate.get(), {KeyUsage::kDigitalSignature}));
    if (t.eku_nid != NID_undef) {
      ASSERT_TRUE(AddExtendedKeyUsage(intermediate.get(), {t.eku_nid}));
    }
    ASSERT_TRUE(X509_sign(intermediate.get(), key.get(), EVP_sha256()));
    EXPECT_EQ(X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY,
              Verify(leaf.get(), {root.get()}, {intermediate.get()}, {}, 0,
                     configure_callback));

    // The intermediate must have the EKU asserted.
    if (t.eku_nid != NID_undef) {
      intermediate =
          MakeTestCert("Root", "Intermediate", key.get(), /*is_ca=*/true);
      ASSERT_TRUE(intermediate);
      ASSERT_TRUE(AddKeyUsage(intermediate.get(), {KeyUsage::kKeyCertSign}));
      ASSERT_TRUE(AddExtendedKeyUsage(intermediate.get(), {NID_rsaEncryption}));
      ASSERT_TRUE(X509_sign(intermediate.get(), key.get(), EVP_sha256()));
      EXPECT_EQ(X509_V_ERR_INVALID_PURPOSE,
                Verify(leaf.get(), {root.get()}, {intermediate.get()}, {}, 0,
                       configure_callback));
    }
  }
}

TEST(X509Test, Trust) {
  struct Certs {
    UniquePtr<X509> normal;
    UniquePtr<X509> trusted_server, distrusted_server;
    UniquePtr<X509> trusted_any, distrusted_any;
  };
  auto certs_from_pem = [](const char *pem) -> Certs {
    Certs certs;
    certs.normal = CertFromPEM(pem);
    certs.trusted_server = CertFromPEM(pem);
    certs.distrusted_server = CertFromPEM(pem);
    certs.trusted_any = CertFromPEM(pem);
    certs.distrusted_any = CertFromPEM(pem);
    if (certs.normal == nullptr || certs.trusted_server == nullptr ||
        certs.distrusted_server == nullptr || certs.trusted_any == nullptr ||
        certs.distrusted_any == nullptr ||
        !X509_add1_trust_object(certs.trusted_server.get(),
                                OBJ_nid2obj(NID_server_auth)) ||
        !X509_add1_reject_object(certs.distrusted_server.get(),
                                 OBJ_nid2obj(NID_server_auth)) ||
        !X509_add1_trust_object(certs.trusted_any.get(),
                                OBJ_nid2obj(NID_anyExtendedKeyUsage)) ||
        !X509_add1_reject_object(certs.distrusted_any.get(),
                                 OBJ_nid2obj(NID_anyExtendedKeyUsage))) {
      return Certs{};
    }
    return certs;
  };

  Certs root = certs_from_pem(kRootCAPEM);
  Certs intermediate = certs_from_pem(kIntermediatePEM);
  Certs leaf = certs_from_pem(kLeafPEM);
  ASSERT_TRUE(root.normal);
  ASSERT_TRUE(intermediate.normal);
  ASSERT_TRUE(leaf.normal);

  // By default, trust is determined by a combination of self-signedness and
  // NID_anyExtendedKeyUsage.
  EXPECT_EQ(X509_V_OK, Verify(leaf.normal.get(), {root.normal.get()},
                              {intermediate.normal.get()}, {}));
  EXPECT_EQ(X509_V_OK, Verify(leaf.normal.get(), {root.trusted_any.get()},
                              {intermediate.normal.get()}, {}));
  EXPECT_EQ(X509_V_ERR_CERT_REJECTED,
            Verify(leaf.normal.get(), {root.distrusted_any.get()},
                   {intermediate.normal.get()}, {}));

  // Intermediate certificates are not self-signed, so must have an
  // NID_anyExtendedKeyUsage trust setting.
  EXPECT_EQ(X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT,
            Verify(leaf.normal.get(), {intermediate.normal.get()}, {}, {}));
  EXPECT_EQ(X509_V_OK, Verify(leaf.normal.get(),
                              {intermediate.trusted_any.get()}, {}, {}));
  EXPECT_EQ(
      X509_V_ERR_CERT_REJECTED,
      Verify(leaf.normal.get(), {intermediate.distrusted_any.get()}, {}, {}));

  // If a certificate has trust settings, but only for a different OID, the
  // self-signed rule still takes effect.
  EXPECT_EQ(X509_V_OK, Verify(leaf.normal.get(), {root.trusted_server.get()},
                              {intermediate.normal.get()}, {}));
  EXPECT_EQ(X509_V_OK, Verify(leaf.normal.get(), {root.distrusted_server.get()},
                              {intermediate.normal.get()}, {}));
  EXPECT_EQ(
      X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT,
      Verify(leaf.normal.get(), {intermediate.trusted_server.get()}, {}, {}));

  // `X509_TRUST_SSL_SERVER` should instead look at self-signedness and
  // `NID_server_auth`.
  auto set_server_trust = [](X509_STORE_CTX *ctx) {
    X509_STORE_CTX_set_trust(ctx, X509_TRUST_SSL_SERVER);
  };
  EXPECT_EQ(X509_V_OK, Verify(leaf.normal.get(), {root.normal.get()},
                              {intermediate.normal.get()}, {}, /*flags=*/0,
                              set_server_trust));
  EXPECT_EQ(X509_V_OK, Verify(leaf.normal.get(), {root.trusted_server.get()},
                              {intermediate.normal.get()}, {}, /*flags=*/0,
                              set_server_trust));
  EXPECT_EQ(
      X509_V_ERR_CERT_REJECTED,
      Verify(leaf.normal.get(), {root.distrusted_server.get()},
             {intermediate.normal.get()}, {}, /*flags=*/0, set_server_trust));

  EXPECT_EQ(X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT,
            Verify(leaf.normal.get(), {intermediate.normal.get()}, {}, {},
                   /*flags=*/0, set_server_trust));
  EXPECT_EQ(X509_V_OK, Verify(leaf.normal.get(),
                              {intermediate.trusted_server.get()}, {}, {},
                              /*flags=*/0, set_server_trust));
  EXPECT_EQ(X509_V_ERR_CERT_REJECTED,
            Verify(leaf.normal.get(), {intermediate.distrusted_server.get()},
                   {}, {}, /*flags=*/0, set_server_trust));

  // NID_anyExtendedKeyUsage is just an unrelated OID to X509_TRUST_SSL_SERVER.
  // Unlike the default behavior, once a certificate has explicit trust settings
  // for any OID, the self-signed check is disabled.
  EXPECT_EQ(
      X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT,
      Verify(leaf.normal.get(), {root.trusted_any.get()},
             {intermediate.normal.get()}, {}, /*flags=*/0, set_server_trust));

  // Trust settings on a certificate are ignored if the leaf did not come from
  // `X509_STORE`. This is important because trust settings may be serialized
  // via `d2i_X509_AUX`. It is often not obvious which functions may trigger
  // this, so callers may inadvertently run with attacker-supplied trust
  // settings on untrusted certificates.
  EXPECT_EQ(X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY,
            Verify(leaf.trusted_server.get(), /*roots=*/{},
                   /*intermediates=*/{intermediate.trusted_server.get()}, {},
                   /*flags=*/0, set_server_trust));
  EXPECT_EQ(
      X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN,
      Verify(leaf.trusted_server.get(), /*roots=*/{},
             /*intermediates=*/
             {intermediate.trusted_server.get(), root.trusted_server.get()}, {},
             /*flags=*/0, set_server_trust));

  // Likewise, distrusts only take effect from `X509_STORE`.
  EXPECT_EQ(X509_V_OK, Verify(leaf.distrusted_server.get(), {root.normal.get()},
                              {intermediate.normal.get()}, {},
                              /*flags=*/0, set_server_trust));
}

// Test some APIs that rust-openssl uses to look up purposes by name.
TEST(X509Test, PurposeByShortName) {
  int idx = X509_PURPOSE_get_by_sname("sslserver");
  ASSERT_NE(idx, -1);
  const X509_PURPOSE *purpose = X509_PURPOSE_get0(idx);
  ASSERT_TRUE(purpose);
  EXPECT_EQ(X509_PURPOSE_get_id(purpose), X509_PURPOSE_SSL_SERVER);
}

TEST(X509Test, CriticalExtension) {
  UniquePtr<EVP_PKEY> key = PrivateKeyFromPEM(kP256Key);
  ASSERT_TRUE(key);

  UniquePtr<X509> root =
      MakeTestCert("Root", "Root", key.get(), /*is_ca=*/true);
  ASSERT_TRUE(root);
  ASSERT_TRUE(X509_sign(root.get(), key.get(), EVP_sha256()));

  // Issue a certificate with a critical Netscape certificate type extension. We
  // do not recognize this extension, so this certificate should be rejected.
  UniquePtr<X509> leaf =
      MakeTestCert("Root", "Leaf", key.get(), /*is_ca=*/false);
  ASSERT_TRUE(leaf);
  UniquePtr<ASN1_BIT_STRING> cert_type(ASN1_BIT_STRING_new());
  ASSERT_TRUE(cert_type);
  ASSERT_TRUE(ASN1_BIT_STRING_set_bit(cert_type.get(), /*n=*/0, /*value=*/1));
  ASSERT_TRUE(X509_add1_ext_i2d(leaf.get(), NID_netscape_cert_type,
                                cert_type.get(),
                                /*crit=*/1, /*flags=*/0));
  ASSERT_TRUE(X509_sign(leaf.get(), key.get(), EVP_sha256()));

  EXPECT_EQ(X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION,
            Verify(leaf.get(), {root.get()}, {}, {}));
  EXPECT_EQ(X509_V_OK, Verify(leaf.get(), {root.get()}, {}, {},
                              X509_V_FLAG_IGNORE_CRITICAL));
}

enum NameHash { kOldHash, kNewHash };

// TemporaryHashDir constructs a temporary directory in the format of
// `X509_LOOKUP_hash_dir`.
class TemporaryHashDir {
 public:
  explicit TemporaryHashDir(int type) : type_(type) {}

  bool Init() { return dir_.Init(); }
  const std::string &path() const { return dir_.path(); }

  size_t num_cert_hashes() const { return next_cert_.size(); }
  size_t num_crl_hashes() const { return next_crl_.size(); }

  bool AddCert(X509 *x509, NameHash name_hash) {
    return AddCertWithHash(HashName(name_hash, X509_get_subject_name(x509)),
                           x509);
  }

  bool AddCRL(X509_CRL *crl, NameHash name_hash) {
    return AddCRLWithHash(HashName(name_hash, X509_CRL_get_issuer(crl)), crl);
  }

  bool AddCertWithHash(uint32_t hash, X509 *cert) {
    std::vector<uint8_t> data = EncodeCert(cert);
    if (data.empty()) {
      return false;
    }
    auto &num = next_cert_[hash];
    char path[32];
    snprintf(path, sizeof(path), "%08x.%d", hash, num);
    if (!dir_.AddFile(path, data)) {
      return false;
    }
    num++;
    return true;
  }

  bool AddCRLWithHash(uint32_t hash, X509_CRL *crl) {
    std::vector<uint8_t> data = EncodeCRL(crl);
    if (data.empty()) {
      return false;
    }
    auto &num = next_crl_[hash];
    char path[32];
    snprintf(path, sizeof(path), "%08x.r%d", hash, num);
    if (!dir_.AddFile(path, data)) {
      return false;
    }
    num++;
    return true;
  }

  bool ReplaceLastCRL(X509_CRL *crl, NameHash name_hash) {
    uint32_t hash = HashName(name_hash, X509_CRL_get_issuer(crl));
    auto iter = next_crl_.find(hash);
    if (iter == next_crl_.end()) {
      return false;
    }
    std::vector<uint8_t> data = EncodeCRL(crl);
    if (data.empty()) {
      return false;
    }
    char path[32];
    snprintf(path, sizeof(path), "%08x.r%d", hash, iter->second - 1);
    return dir_.AddFile(path, data);
  }

 private:
  static uint32_t HashName(NameHash name_hash, X509_NAME *name) {
    return name_hash == kOldHash ? X509_NAME_hash_old(name)
                                 : X509_NAME_hash(name);
  }

  std::vector<uint8_t> EncodeCert(X509 *cert) {
    if (type_ == X509_FILETYPE_ASN1) {
      uint8_t *der = nullptr;
      int der_len = i2d_X509(cert, &der);
      if (der_len < 0) {
        return {};
      }
      UniquePtr<uint8_t> free_der(der);
      return std::vector<uint8_t>(der, der + der_len);
    }

    UniquePtr<BIO> bio(BIO_new(BIO_s_mem()));
    const uint8_t *pem;
    size_t pem_len;
    if (bio == nullptr ||  //
        !PEM_write_bio_X509(bio.get(), cert) ||
        !BIO_mem_contents(bio.get(), &pem, &pem_len)) {
      return {};
    }
    return std::vector<uint8_t>(pem, pem + pem_len);
  }

  std::vector<uint8_t> EncodeCRL(X509_CRL *crl) {
    if (type_ == X509_FILETYPE_ASN1) {
      uint8_t *der = nullptr;
      int der_len = i2d_X509_CRL(crl, &der);
      if (der_len < 0) {
        return {};
      }
      UniquePtr<uint8_t> free_der(der);
      return std::vector<uint8_t>(der, der + der_len);
    }

    UniquePtr<BIO> bio(BIO_new(BIO_s_mem()));
    const uint8_t *pem;
    size_t pem_len;
    if (bio == nullptr ||  //
        !PEM_write_bio_X509_CRL(bio.get(), crl) ||
        !BIO_mem_contents(bio.get(), &pem, &pem_len)) {
      return {};
    }
    return std::vector<uint8_t>(pem, pem + pem_len);
  }

  int type_;
  TemporaryDirectory dir_;
  std::map<uint32_t, int> next_cert_;
  std::map<uint32_t, int> next_crl_;
};

// TODO(davidben): Also test CRL handling. There are some interesting behaviors
// in here.
TEST(X509Test, DirHash) {
  if (SkipTempFileTests()) {
    GTEST_SKIP();
  }

  UniquePtr<EVP_PKEY> key = PrivateKeyFromPEM(kP256Key);
  ASSERT_TRUE(key);

  // Test both formats.
  for (int type : {X509_FILETYPE_PEM, X509_FILETYPE_ASN1}) {
    SCOPED_TRACE(type);

    // Generate some roots and fill a directory with OpenSSL's directory hash
    // format. The hash depends only on the name, so we do not need to
    // pre-generate the certificates. Test both DER and PEM.
    TemporaryHashDir dir(type);
    ASSERT_TRUE(dir.Init());

    auto add_root = [&](std::string_view name, NameHash name_hash) -> bool {
      UniquePtr<X509> ca = MakeTestCert(name, name, key.get(), /*is_ca=*/true);
      if (ca == nullptr || !X509_sign(ca.get(), key.get(), EVP_sha256())) {
        return false;
      }
      return dir.AddCert(ca.get(), name_hash);
    };

    auto issue_crl =
        [&](std::string_view name, int this_update_offset_day,
            const std::vector<uint64_t> &serials) -> UniquePtr<X509_CRL> {
      UniquePtr<X509_CRL> crl = MakeTestCRL(name, this_update_offset_day,
                                            /*next_update_offset_day=*/1);
      if (crl == nullptr) {
        return nullptr;
      }
      for (uint64_t serial : serials) {
        // The revocation time does not matter for this test. Pretend the
        // certificate was just revoked.
        if (!AddRevokedSerialU64(crl.get(), serial,
                                 /*offset_day=*/this_update_offset_day)) {
          return nullptr;
        }
      }
      if (!X509_CRL_sign(crl.get(), key.get(), EVP_sha256())) {
        return nullptr;
      }
      return crl;
    };

    auto add_crl = [&](std::string_view name, NameHash name_hash,
                       int this_update_offset_day,
                       const std::vector<uint64_t> &serials) -> bool {
      UniquePtr<X509_CRL> crl =
          issue_crl(name, this_update_offset_day, serials);
      return crl != nullptr && dir.AddCRL(crl.get(), name_hash);
    };

    std::string ca1 = "Test CA 1";
    ASSERT_TRUE(add_root(ca1, kNewHash));

    std::string ca2 = "Test CA 2";
    ASSERT_TRUE(add_root(ca2, kOldHash));

    // Install CA 3 at its new hash. CA 3's name is not canonical, but the new
    // hash runs after canonicalization, so OpenSSL should be able to find it.
    std::string ca3 = "Test CA 3";
    std::string ca3_noncanonical = "   test   ca   3   ";
    ASSERT_TRUE(add_root(ca3_noncanonical, kNewHash));

    // These two CAs collide under `X509_NAME_hash`.
    std::string collide_name1 = "Test CA 1191514847";
    std::string collide_name2 = "Test CA 1570301806";
    size_t num_cert_hashes = dir.num_cert_hashes();
    ASSERT_TRUE(add_root(collide_name1, kNewHash));
    EXPECT_EQ(dir.num_cert_hashes(), num_cert_hashes + 1);
    ASSERT_TRUE(add_root(collide_name2, kNewHash));
    EXPECT_EQ(dir.num_cert_hashes(), num_cert_hashes + 1);

    // These two CAs collide under `X509_NAME_hash_old`.
    std::string old_collide_name1 = "Test CA 1069881739";
    std::string old_collide_name2 = "Test CA 940754110";
    num_cert_hashes = dir.num_cert_hashes();
    ASSERT_TRUE(add_root(old_collide_name1, kOldHash));
    EXPECT_EQ(dir.num_cert_hashes(), num_cert_hashes + 1);
    ASSERT_TRUE(add_root(old_collide_name2, kOldHash));
    EXPECT_EQ(dir.num_cert_hashes(), num_cert_hashes + 1);

    // Make an `X509_STORE` that gets CAs from `dir`.
    UniquePtr<X509_STORE> store(X509_STORE_new());
    ASSERT_TRUE(store);
    X509_LOOKUP *lookup =
        X509_STORE_add_lookup(store.get(), X509_LOOKUP_hash_dir());
    ASSERT_TRUE(lookup);
    ASSERT_TRUE(X509_LOOKUP_add_dir(lookup, dir.path().c_str(), type));

    auto test_issuer_flags = [&](const std::string &issuer, uint64_t serial,
                                 unsigned long flags) -> int {
      UniquePtr<X509> cert =
          MakeTestCert(issuer, "Leaf", key.get(), /*is_ca=*/false);
      UniquePtr<ASN1_INTEGER> serial_asn1(ASN1_INTEGER_new());
      if (cert == nullptr || serial_asn1 == nullptr ||
          !ASN1_INTEGER_set_uint64(serial_asn1.get(), serial) ||
          !X509_set_serialNumber(cert.get(), serial_asn1.get()) ||
          !X509_sign(cert.get(), key.get(), EVP_sha256())) {
        return X509_V_ERR_UNSPECIFIED;
      }

      UniquePtr<X509_STORE_CTX> ctx(X509_STORE_CTX_new());
      if (ctx == nullptr ||
          !X509_STORE_CTX_init(ctx.get(), store.get(), cert.get(),
                               /*chain=*/nullptr)) {
        return X509_V_ERR_UNSPECIFIED;
      }
      X509_STORE_CTX_set_flags(ctx.get(), flags);
      X509_STORE_CTX_set_time_posix(ctx.get(), /*flags=*/0, kReferenceTime);

      return X509_verify_cert(ctx.get()) ? X509_V_OK
                                         : X509_STORE_CTX_get_error(ctx.get());
    };

    auto test_issuer = [&](const std::string &issuer) -> int {
      return test_issuer_flags(issuer, /*serial=*/0, /*flags=*/0);
    };
    auto test_issuer_crl = [&](const std::string &issuer,
                               uint64_t serial) -> int {
      return test_issuer_flags(issuer, serial, X509_V_FLAG_CRL_CHECK);
    };

    // All these roots are in the store and should be found. Although Test CA
    // 3 was installed under a non-canonical name, the new hash accounts for
    // this.
    EXPECT_EQ(X509_V_OK, test_issuer(ca1));
    EXPECT_EQ(X509_V_OK, test_issuer(ca2));
    EXPECT_EQ(X509_V_OK, test_issuer(ca3));
    EXPECT_EQ(X509_V_OK, test_issuer(collide_name1));
    EXPECT_EQ(X509_V_OK, test_issuer(collide_name2));
    EXPECT_EQ(X509_V_OK, test_issuer(old_collide_name1));
    EXPECT_EQ(X509_V_OK, test_issuer(old_collide_name2));

    // Repeat the tests. This time it will pick up the certificate from the
    // cache.
    EXPECT_EQ(X509_V_OK, test_issuer(ca1));
    EXPECT_EQ(X509_V_OK, test_issuer(ca2));
    EXPECT_EQ(X509_V_OK, test_issuer(ca3));
    EXPECT_EQ(X509_V_OK, test_issuer(collide_name1));
    EXPECT_EQ(X509_V_OK, test_issuer(collide_name2));
    EXPECT_EQ(X509_V_OK, test_issuer(old_collide_name1));
    EXPECT_EQ(X509_V_OK, test_issuer(old_collide_name2));

    // Test a certificate not in the store.
    ERR_clear_error();
    EXPECT_EQ(X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY,
              test_issuer("Not In Store"));

    // Although, internally, this hits the filesystem and finds that a file does
    // not exist, there should not be anything on the error queue about a
    // missing file. `X509_verify_cert` generally does not use the error queue,
    // so it will be empty. See https://crbug.com/boringssl/708.
    EXPECT_EQ(ERR_get_error(), 0u);

    // Test CRL handling. First, if we cannot find a CRL, verification will
    // fail.
    //
    // TODO(crbug.com/boringssl/690): We should test both the old and new hash,
    // but the CRL reloading process does not work for the old hash due to a
    // bug. It notices the cached old CRL, mistakes it for something loaded via
    // the new hash, and never bothers checking the old hash.
    EXPECT_EQ(X509_V_ERR_UNABLE_TO_GET_CRL,
              test_issuer_crl(collide_name1, /*serial=*/1));

    // Install an empty CRL. Verification should now succeed.
    ASSERT_TRUE(add_crl(collide_name1, kNewHash,
                        /*this_update_offset_day=*/-10, /*serials=*/{}));
    EXPECT_EQ(X509_V_OK, test_issuer_crl(collide_name1, /*serial=*/1));

    // Verify again. Unlike roots, which are cached, this will query the
    // directory again.
    EXPECT_EQ(X509_V_OK, test_issuer_crl(collide_name1, /*serial=*/1));

    // The extra query is so that a newer CRL is picked up, at an incrementing
    // number. This feature is less useful than it sounds because all CRLs are
    // persistently cached.
    ASSERT_TRUE(add_crl(collide_name1, kNewHash,
                        /*this_update_offset_day=*/-9, /*serials=*/{1}));
    EXPECT_EQ(X509_V_ERR_CERT_REVOKED,
              test_issuer_crl(collide_name1, /*serial=*/1));

    // Serial number 2 is not revoked.
    EXPECT_EQ(X509_V_OK, test_issuer_crl(collide_name1, /*serial=*/2));

    // A new CRL at an already loaded name is ignored because OpenSSL skips
    // loading the older ones and relies on them being persistently cached in
    // memory.
    //
    // TODO(crbug.com/boringssl/690): This behavior is almost certainly not what
    // anyone wants. Rework this.
    UniquePtr<X509_CRL> crl = issue_crl(
        collide_name1, /*this_update_offset_day=*/-8, /*serials=*/{1, 2});
    ASSERT_TRUE(crl);
    ASSERT_TRUE(dir.ReplaceLastCRL(crl.get(), kNewHash));
    EXPECT_EQ(X509_V_OK, test_issuer_crl(collide_name1, /*serial=*/2));

    // If there are many new CRLs, they are all loaded and the newest is wins.
    ASSERT_TRUE(add_crl(collide_name1, kNewHash,
                        /*this_update_offset_day=*/-7, /*serials=*/{1, 2}));
    ASSERT_TRUE(add_crl(collide_name1, kNewHash,
                        /*this_update_offset_day=*/-5, /*serials=*/{1, 2, 3}));
    ASSERT_TRUE(add_crl(collide_name1, kNewHash,
                        /*this_update_offset_day=*/-6, /*serials=*/{1, 2}));

    // r3 should have won, which revokes all three serials:
    EXPECT_EQ(X509_V_ERR_CERT_REVOKED,
              test_issuer_crl(collide_name1, /*serial=*/1));
    EXPECT_EQ(X509_V_ERR_CERT_REVOKED,
              test_issuer_crl(collide_name1, /*serial=*/2));
    EXPECT_EQ(X509_V_ERR_CERT_REVOKED,
              test_issuer_crl(collide_name1, /*serial=*/3));

    // If the new CRL is older than a previously loaded one, it is ignored.
    ASSERT_TRUE(add_crl(collide_name1, kNewHash,
                        /*this_update_offset_day=*/-100, /*serials=*/{}));

    // Finally, test hash collisions. The internal book-keeping for where to
    // start loading should be compatible with a second CA whose hash collides.
    EXPECT_EQ(X509_V_ERR_UNABLE_TO_GET_CRL,
              test_issuer_crl(collide_name2, /*serial=*/1));
    EXPECT_EQ(X509_V_ERR_UNABLE_TO_GET_CRL,
              test_issuer_crl(collide_name2, /*serial=*/2));
    ASSERT_TRUE(add_crl(collide_name2, kNewHash,
                        /*this_update_offset_day=*/-10, /*serials=*/{1}));
    EXPECT_EQ(X509_V_ERR_CERT_REVOKED,
              test_issuer_crl(collide_name2, /*serial=*/1));
    EXPECT_EQ(X509_V_OK, test_issuer_crl(collide_name2, /*serial=*/2));

    // Confirm all CRLs we added had the same hash.
    EXPECT_EQ(dir.num_crl_hashes(), 1u);
  }
}

// Test that two directory hash paths are treated as a sequence of paths,
// separated by a separator.
TEST(X509Test, DirHashSeparator) {
#if defined(OPENSSL_WINDOWS)
  const char kSeparator = ';';
#else
  const char kSeparator = ':';
#endif

  if (SkipTempFileTests()) {
    GTEST_SKIP();
  }

  UniquePtr<EVP_PKEY> key = PrivateKeyFromPEM(kP256Key);
  ASSERT_TRUE(key);

  // Make two directories and place one CA in each.
  TemporaryHashDir dir1(X509_FILETYPE_PEM), dir2(X509_FILETYPE_PEM);
  ASSERT_TRUE(dir1.Init());
  ASSERT_TRUE(dir2.Init());

  UniquePtr<X509> ca1 =
      MakeTestCert("Test CA 1", "Test CA 1", key.get(), /*is_ca=*/true);
  ASSERT_TRUE(ca1);
  ASSERT_TRUE(X509_sign(ca1.get(), key.get(), EVP_sha256()));
  ASSERT_TRUE(dir1.AddCert(ca1.get(), kNewHash));

  UniquePtr<X509> ca2 =
      MakeTestCert("Test CA 2", "Test CA 2", key.get(), /*is_ca=*/true);
  ASSERT_TRUE(ca2);
  ASSERT_TRUE(X509_sign(ca2.get(), key.get(), EVP_sha256()));
  ASSERT_TRUE(dir1.AddCert(ca2.get(), kNewHash));

  for (bool duplicates : {false, true}) {
    SCOPED_TRACE(duplicates);

    // Make an `X509_STORE` that gets CAs from `dir1` and `dir2`.
    UniquePtr<X509_STORE> store(X509_STORE_new());
    ASSERT_TRUE(store);
    std::string paths = dir1.path() + kSeparator + dir2.path();
    if (duplicates) {
      // Within a path, duplicates are silently ignored.
      paths += kSeparator + paths;
    }
    ASSERT_TRUE(X509_STORE_load_locations(store.get(), /*file=*/nullptr,
                                          paths.c_str()));
    if (duplicates) {
      // Across calls, duplicates are silently ignored.
      ASSERT_TRUE(X509_STORE_load_locations(store.get(), /*file=*/nullptr,
                                            paths.c_str()));
    }

    // Both CAs should work.
    {
      UniquePtr<X509> cert =
          MakeTestCert("Test CA 1", "Leaf", key.get(), /*is_ca=*/false);
      ASSERT_TRUE(cert);
      ASSERT_TRUE(X509_sign(cert.get(), key.get(), EVP_sha256()));
      UniquePtr<X509_STORE_CTX> ctx(X509_STORE_CTX_new());
      ASSERT_TRUE(ctx);
      ASSERT_TRUE(X509_STORE_CTX_init(ctx.get(), store.get(), cert.get(),
                                      /*chain=*/nullptr));
      X509_STORE_CTX_set_time_posix(ctx.get(), /*flags=*/0, kReferenceTime);
      EXPECT_TRUE(X509_verify_cert(ctx.get()))
          << X509_verify_cert_error_string(X509_STORE_CTX_get_error(ctx.get()));
    }

    {
      UniquePtr<X509> cert =
          MakeTestCert("Test CA 2", "Leaf", key.get(), /*is_ca=*/false);
      ASSERT_TRUE(cert);
      ASSERT_TRUE(X509_sign(cert.get(), key.get(), EVP_sha256()));
      UniquePtr<X509_STORE_CTX> ctx(X509_STORE_CTX_new());
      ASSERT_TRUE(ctx);
      ASSERT_TRUE(X509_STORE_CTX_init(ctx.get(), store.get(), cert.get(),
                                      /*chain=*/nullptr));
      X509_STORE_CTX_set_time_posix(ctx.get(), /*flags=*/0, kReferenceTime);
      EXPECT_TRUE(X509_verify_cert(ctx.get()))
          << X509_verify_cert_error_string(X509_STORE_CTX_get_error(ctx.get()));
    }
  }
}

#if defined(OPENSSL_THREADS)
// Test that directory hash lookup is thread-safe.
TEST(X509Test, DirHashThreads) {
  if (SkipTempFileTests()) {
    GTEST_SKIP();
  }

  UniquePtr<EVP_PKEY> key = PrivateKeyFromPEM(kP256Key);
  ASSERT_TRUE(key);

  // Generate some roots and fill a directory with OpenSSL's directory hash
  // format. The hash depends only on the name, so we do not need to
  // pre-generate the certificates. Test both DER and PEM.
  TemporaryHashDir dir(X509_FILETYPE_PEM);
  ASSERT_TRUE(dir.Init());

  auto add_root = [&](const std::string &name, NameHash name_hash) -> bool {
    UniquePtr<X509> ca = MakeTestCert(name, name, key.get(), /*is_ca=*/true);
    return ca != nullptr &&  //
           X509_sign(ca.get(), key.get(), EVP_sha256()) &&
           dir.AddCert(ca.get(), name_hash);
  };

  auto issue_cert = [&](const std::string &issuer) -> UniquePtr<X509> {
    UniquePtr<X509> cert =
        MakeTestCert(issuer, "Leaf", key.get(), /*is_ca=*/false);
    if (cert == nullptr || !X509_sign(cert.get(), key.get(), EVP_sha256())) {
      return nullptr;
    }
    return cert;
  };

  auto add_crl = [&](const std::string &name, int this_update_offset_day,
                     NameHash name_hash) -> bool {
    UniquePtr<X509_CRL> crl =
        MakeTestCRL(name, this_update_offset_day, /*next_update_offset_day=*/1);
    return crl != nullptr &&
           X509_CRL_sign(crl.get(), key.get(), EVP_sha256()) &&
           dir.AddCRL(crl.get(), name_hash);
  };

  // These two CAs collide under `X509_NAME_hash`.
  std::string ca1 = "Test CA 1191514847";
  std::string ca2 = "Test CA 1570301806";
  ASSERT_TRUE(add_root(ca1, kNewHash));
  ASSERT_TRUE(add_root(ca2, kNewHash));
  ASSERT_TRUE(add_crl(ca1, -2, kNewHash));
  ASSERT_TRUE(add_crl(ca2, -1, kNewHash));
  ASSERT_TRUE(add_crl(ca2, -2, kNewHash));
  ASSERT_TRUE(add_crl(ca1, -1, kNewHash));
  // Verify the hashes collided.
  ASSERT_EQ(dir.num_cert_hashes(), 1u);
  ASSERT_EQ(dir.num_crl_hashes(), 1u);
  UniquePtr<X509> leaf1 = issue_cert(ca1);
  ASSERT_TRUE(leaf1);
  UniquePtr<X509> leaf2 = issue_cert(ca2);
  ASSERT_TRUE(leaf2);

  // These two CAs collide under `X509_NAME_hash_old`.
  std::string old_ca1 = "Test CA 1069881739";
  std::string old_ca2 = "Test CA 940754110";
  ASSERT_TRUE(add_root(old_ca1, kOldHash));
  ASSERT_TRUE(add_root(old_ca2, kOldHash));
  ASSERT_TRUE(add_crl(old_ca1, -2, kOldHash));
  ASSERT_TRUE(add_crl(old_ca2, -1, kOldHash));
  ASSERT_TRUE(add_crl(old_ca2, -2, kOldHash));
  ASSERT_TRUE(add_crl(old_ca1, -1, kOldHash));
  // Verify the hashes collided.
  ASSERT_EQ(dir.num_cert_hashes(), 2u);
  ASSERT_EQ(dir.num_crl_hashes(), 2u);
  UniquePtr<X509> old_leaf1 = issue_cert(old_ca1);
  ASSERT_TRUE(old_leaf1);
  UniquePtr<X509> old_leaf2 = issue_cert(old_ca2);
  ASSERT_TRUE(old_leaf2);

  // Make an `X509_STORE` that gets CAs from `dir`.
  UniquePtr<X509_STORE> store(X509_STORE_new());
  ASSERT_TRUE(store);
  ASSERT_TRUE(X509_STORE_load_locations(store.get(), /*file=*/nullptr,
                                        dir.path().c_str()));

  auto verify = [&](X509 *cert, bool crl_check) {
    UniquePtr<X509_STORE_CTX> ctx(X509_STORE_CTX_new());
    ASSERT_TRUE(ctx);
    ASSERT_TRUE(X509_STORE_CTX_init(ctx.get(), store.get(), cert,
                                    /*chain=*/nullptr));
    X509_STORE_CTX_set_flags(ctx.get(), crl_check ? X509_V_FLAG_CRL_CHECK : 0);
    X509_STORE_CTX_set_time_posix(ctx.get(), /*flags=*/0, kReferenceTime);
    EXPECT_TRUE(X509_verify_cert(ctx.get()))
        << X509_verify_cert_error_string(X509_STORE_CTX_get_error(ctx.get()));
  };

  const size_t kNumThreads = 10;
  std::vector<std::thread> threads;
  for (size_t i = 0; i < kNumThreads; i++) {
    threads.emplace_back([&] { verify(leaf1.get(), false); });
    threads.emplace_back([&] { verify(leaf1.get(), true); });
    threads.emplace_back([&] { verify(leaf2.get(), false); });
    threads.emplace_back([&] { verify(leaf2.get(), true); });

    threads.emplace_back([&] { verify(old_leaf1.get(), false); });
    threads.emplace_back([&] { verify(old_leaf1.get(), true); });
    threads.emplace_back([&] { verify(old_leaf2.get(), false); });
    threads.emplace_back([&] { verify(old_leaf2.get(), true); });
  }
  for (auto &thread : threads) {
    thread.join();
  }
}
#endif  // OPENSSL_THREADS

// Test that, when there are two CAs with the same name, but different key
// identifiers, certificate and CRL lookup can disambiguate correctly.
TEST(X509Test, DuplicateName) {
  // Make two certificate chains and empty CRLs, with the same names but
  // different keys.
  UniquePtr<EVP_PKEY> key1 = PrivateKeyFromPEM(kP256Key);
  ASSERT_TRUE(key1);
  uint8_t key_id1[] = {'K', 'e', 'y', '1'};
  UniquePtr<X509> ca1 = MakeTestCert("CA", "CA", key1.get(), /*is_ca=*/true);
  ASSERT_TRUE(ca1);
  ASSERT_TRUE(AddSubjectKeyIdentifier(ca1.get(), key_id1));
  ASSERT_TRUE(X509_sign(ca1.get(), key1.get(), EVP_sha256()));
  UniquePtr<X509> leaf1 =
      MakeTestCert("CA", "Leaf", key1.get(), /*is_ca=*/false);
  ASSERT_TRUE(leaf1);
  ASSERT_TRUE(AddAuthorityKeyIdentifier(leaf1.get(), key_id1));
  ASSERT_TRUE(X509_sign(leaf1.get(), key1.get(), EVP_sha256()));
  UniquePtr<X509_CRL> crl1 = MakeTestCRL("CA", -1, 1);
  ASSERT_TRUE(crl1);
  ASSERT_TRUE(AddAuthorityKeyIdentifier(crl1.get(), key_id1));
  ASSERT_TRUE(X509_CRL_sign(crl1.get(), key1.get(), EVP_sha256()));
  // TODO(davidben): Some state in CRLs does not get correctly set up unless it
  // is parsed from data. `X509_CRL_sign` should reset it internally.
  crl1 = ReencodeCRL(crl1.get());
  ASSERT_TRUE(crl1);

  UniquePtr<EVP_PKEY> key2 = PrivateKeyFromPEM(kRSAKey);
  ASSERT_TRUE(key2);
  uint8_t key_id2[] = {'K', 'e', 'y', '2'};
  UniquePtr<X509> ca2 = MakeTestCert("CA", "CA", key2.get(), /*is_ca=*/true);
  ASSERT_TRUE(ca2);
  ASSERT_TRUE(AddSubjectKeyIdentifier(ca2.get(), key_id2));
  ASSERT_TRUE(X509_sign(ca2.get(), key2.get(), EVP_sha256()));
  UniquePtr<X509> leaf2 =
      MakeTestCert("CA", "Leaf", key2.get(), /*is_ca=*/false);
  ASSERT_TRUE(leaf2);
  ASSERT_TRUE(AddAuthorityKeyIdentifier(leaf2.get(), key_id2));
  ASSERT_TRUE(X509_sign(leaf2.get(), key2.get(), EVP_sha256()));
  UniquePtr<X509_CRL> crl2 = MakeTestCRL("CA", -2, 2);
  ASSERT_TRUE(crl2);
  ASSERT_TRUE(AddAuthorityKeyIdentifier(crl2.get(), key_id2));
  ASSERT_TRUE(X509_CRL_sign(crl2.get(), key2.get(), EVP_sha256()));
  // TODO(davidben): Some state in CRLs does not get correctly set up unless it
  // is parsed from data. `X509_CRL_sign` should reset it internally.
  crl2 = ReencodeCRL(crl2.get());
  ASSERT_TRUE(crl2);

  for (bool key1_first : {false, true}) {
    SCOPED_TRACE(key1_first);
    X509 *first_leaf = leaf1.get();
    X509 *second_leaf = leaf2.get();
    if (!key1_first) {
      std::swap(first_leaf, second_leaf);
    }

    for (bool use_dir : {false, true}) {
      SCOPED_TRACE(use_dir);
      UniquePtr<X509_STORE> store(X509_STORE_new());
      ASSERT_TRUE(store);
      TemporaryHashDir dir(X509_FILETYPE_PEM);
      if (use_dir) {
        ASSERT_TRUE(dir.Init());
        ASSERT_TRUE(dir.AddCert(ca1.get(), kNewHash));
        ASSERT_TRUE(dir.AddCert(ca2.get(), kNewHash));
        ASSERT_TRUE(dir.AddCRL(crl1.get(), kNewHash));
        ASSERT_TRUE(dir.AddCRL(crl2.get(), kNewHash));
        ASSERT_EQ(dir.num_cert_hashes(), 1u);
        ASSERT_EQ(dir.num_crl_hashes(), 1u);
        ASSERT_TRUE(X509_STORE_load_locations(store.get(), /*file=*/nullptr,
                                              dir.path().c_str()));
      } else {
        ASSERT_TRUE(X509_STORE_add_cert(store.get(), ca1.get()));
        ASSERT_TRUE(X509_STORE_add_cert(store.get(), ca2.get()));
        ASSERT_TRUE(X509_STORE_add_crl(store.get(), crl1.get()));
        ASSERT_TRUE(X509_STORE_add_crl(store.get(), crl2.get()));
      }

      // Verify the two certificates. Whichever comes first, we should
      // successfully find their CA and CRL.
      {
        UniquePtr<X509_STORE_CTX> ctx(X509_STORE_CTX_new());
        ASSERT_TRUE(ctx);
        ASSERT_TRUE(
            X509_STORE_CTX_init(ctx.get(), store.get(), first_leaf, nullptr));
        X509_STORE_CTX_set_flags(ctx.get(), X509_V_FLAG_CRL_CHECK);
        X509_STORE_CTX_set_time_posix(ctx.get(), /*flags=*/0, kReferenceTime);
        EXPECT_TRUE(X509_verify_cert(ctx.get()))
            << X509_verify_cert_error_string(
                   X509_STORE_CTX_get_error(ctx.get()));
      }
      {
        UniquePtr<X509_STORE_CTX> ctx(X509_STORE_CTX_new());
        ASSERT_TRUE(ctx);
        ASSERT_TRUE(
            X509_STORE_CTX_init(ctx.get(), store.get(), second_leaf, nullptr));
        X509_STORE_CTX_set_flags(ctx.get(), X509_V_FLAG_CRL_CHECK);
        X509_STORE_CTX_set_time_posix(ctx.get(), /*flags=*/0, kReferenceTime);
        EXPECT_TRUE(X509_verify_cert(ctx.get()))
            << X509_verify_cert_error_string(
                   X509_STORE_CTX_get_error(ctx.get()));
      }
    }
  }
}

TEST(X509Test, ParseIPAddress) {
  const struct {
    const char *inp;
    // out is the expected output, or an empty vector if the parser is expected
    // to fail.
    std::vector<uint8_t> out;
  } kIPTests[] = {
      // Valid IPv4 addresses.
      {"127.0.0.1", {127, 0, 0, 1}},
      {"1.2.3.4", {1, 2, 3, 4}},
      {"1.2.3.255", {1, 2, 3, 255}},
      {"255.255.255.255", {255, 255, 255, 255}},

      // Valid IPv6 addresses
      {"::", {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
      {"::1", {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}},
      {"::01", {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}},
      {"::001", {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}},
      {"::0001", {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}},
      {"ffff::", {0xff, 0xff, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
      {"1::2", {0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2}},
      {"1:1:1:1:1:1:1:1", {0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1}},
      {"2001:db8::ff00:42:8329",
       {0x20, 0x01, 0x0d, 0xb8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0x00,
        0x00, 0x42, 0x83, 0x29}},
      {"1234::1.2.3.4", {0x12, 0x34, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4}},
      {"::1.2.3.4", {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4}},
      {"ffff:ffff:ffff:ffff:ffff:ffff:1.2.3.4",
       {0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
        1, 2, 3, 4}},

      // Too few IPv4 components.
      {"1", {}},
      {"1.", {}},
      {"1.2", {}},
      {"1.2.", {}},
      {"1.2.3", {}},
      {"1.2.3.", {}},

      // Invalid embedded IPv4 address.
      {"::1.2.3", {}},

      // Too many components.
      {"1.2.3.4.5", {}},
      {"1:2:3:4:5:6:7:8:9", {}},
      {"1:2:3:4:5::6:7:8:9", {}},

      // IPv4 literals take the place of two IPv6 components.
      {"1:2:3:4:5:6:7:1.2.3.4", {}},

      // '::' should have fewer than 16 components or it is redundant.
      {"1:2:3:4:5:6:7::8", {}},

      // Embedded IPv4 addresses must be at the end.
      {"::1.2.3.4:1", {}},

      // Stray whitespace or other invalid characters.
      {"1.2.3.4 ", {}},
      {"1.2.3 .4", {}},
      {"1.2.3. 4", {}},
      {" 1.2.3.4", {}},
      {"1.2.3.4.", {}},
      {"1.2.3.+4", {}},
      {"1.2.3.-4", {}},
      {"1.2.3.4.example.test", {}},
      {"::1 ", {}},
      {" ::1", {}},
      {":: 1", {}},
      {": :1", {}},
      {"1.2.3.nope", {}},
      {"::nope", {}},

      // Components too large.
      {"1.2.3.256", {}},  // Overflows when adding
      {"1.2.3.260", {}},  // Overflows when multiplying by 10
      {"1.2.3.999999999999999999999999999999999999999999", {}},
      {"::fffff", {}},

      // Although not an overflow, more than four hex digits is an error.
      {"::00000", {}},

      // Too many colons.
      {":::", {}},
      {"1:::", {}},
      {":::2", {}},
      {"1:::2", {}},

      // Only one group of zeros may be elided.
      {"1::2::3", {}},

      // We only support decimal.
      {"1.2.3.01", {}},
      {"1.2.3.0x1", {}},

      // Random garbage.
      {"example.test", {}},
      {"", {}},
  };
  for (const auto &t : kIPTests) {
    SCOPED_TRACE(t.inp);
    UniquePtr<ASN1_OCTET_STRING> oct(a2i_IPADDRESS(t.inp));
    if (t.out.empty()) {
      EXPECT_FALSE(oct);
    } else {
      ASSERT_TRUE(oct);
      EXPECT_EQ(Bytes(t.out), Bytes(ASN1StringAsBytes(oct.get())));
    }
  }
}

// Test that, after deleting the last extension, the extension list should be
// null.
TEST(X509Test, DeleteLastExtension) {
  UniquePtr<X509_EXTENSION> ext1(X509_EXTENSION_new());
  ASSERT_TRUE(ext1);
  ASSERT_TRUE(X509_EXTENSION_set_object(
      ext1.get(), OBJ_nid2obj(NID_subject_key_identifier)));

  UniquePtr<X509_EXTENSION> ext2(X509_EXTENSION_new());
  ASSERT_TRUE(ext2);
  ASSERT_TRUE(X509_EXTENSION_set_object(
      ext2.get(), OBJ_nid2obj(NID_authority_key_identifier)));

  UniquePtr<X509> cert(X509_new());
  ASSERT_TRUE(cert);
  UniquePtr<X509_CRL> crl(X509_CRL_new());
  ASSERT_TRUE(crl);
  UniquePtr<X509_REVOKED> rev(X509_REVOKED_new());
  ASSERT_TRUE(rev);

  // Initially, the extension list is null.
  EXPECT_EQ(X509_get0_extensions(cert.get()), nullptr);
  EXPECT_EQ(X509_CRL_get0_extensions(crl.get()), nullptr);
  EXPECT_EQ(X509_REVOKED_get0_extensions(rev.get()), nullptr);

  // Add an extension.
  ASSERT_TRUE(X509_add_ext(cert.get(), ext1.get(), -1));
  ASSERT_TRUE(X509_CRL_add_ext(crl.get(), ext1.get(), -1));
  ASSERT_TRUE(X509_REVOKED_add_ext(rev.get(), ext1.get(), -1));
  EXPECT_EQ(sk_X509_EXTENSION_num(X509_get0_extensions(cert.get())), 1u);
  EXPECT_EQ(sk_X509_EXTENSION_num(X509_CRL_get0_extensions(crl.get())), 1u);
  EXPECT_EQ(sk_X509_EXTENSION_num(X509_REVOKED_get0_extensions(rev.get())), 1u);

  // Add a second extension.
  ASSERT_TRUE(X509_add_ext(cert.get(), ext1.get(), -1));
  ASSERT_TRUE(X509_CRL_add_ext(crl.get(), ext1.get(), -1));
  ASSERT_TRUE(X509_REVOKED_add_ext(rev.get(), ext1.get(), -1));
  EXPECT_EQ(sk_X509_EXTENSION_num(X509_get0_extensions(cert.get())), 2u);
  EXPECT_EQ(sk_X509_EXTENSION_num(X509_CRL_get0_extensions(crl.get())), 2u);
  EXPECT_EQ(sk_X509_EXTENSION_num(X509_REVOKED_get0_extensions(rev.get())), 2u);

  // Delete one extension.
  X509_EXTENSION_free(X509_delete_ext(cert.get(), 0));
  X509_EXTENSION_free(X509_CRL_delete_ext(crl.get(), 0));
  X509_EXTENSION_free(X509_REVOKED_delete_ext(rev.get(), 0));

  // There is still an extension list.
  EXPECT_EQ(sk_X509_EXTENSION_num(X509_get0_extensions(cert.get())), 1u);
  EXPECT_EQ(sk_X509_EXTENSION_num(X509_CRL_get0_extensions(crl.get())), 1u);
  EXPECT_EQ(sk_X509_EXTENSION_num(X509_REVOKED_get0_extensions(rev.get())), 1u);

  // Delete the other extension.
  X509_EXTENSION_free(X509_delete_ext(cert.get(), 0));
  X509_EXTENSION_free(X509_CRL_delete_ext(crl.get(), 0));
  X509_EXTENSION_free(X509_REVOKED_delete_ext(rev.get(), 0));

  // There should not only be zero extensions, but not list at all.
  EXPECT_EQ(X509_get0_extensions(cert.get()), nullptr);
  EXPECT_EQ(X509_CRL_get0_extensions(crl.get()), nullptr);
  EXPECT_EQ(X509_REVOKED_get0_extensions(rev.get()), nullptr);
}

// Test that, signatures over unusual TBSCertificates are verified correctly.
// This tests that encoding is correctly round-tripped through the parser to the
// verifier.
//
// In principle, this should never happen because a DER parser will only accept
// the canonical encoding of an object. However, it is possible for encoding to
// not round-trip if we accept any BER inputs, or our in-memory representation
// does not capture the full range of abstract TBSCertificate values.
//
// `X509` objects cache the encoded TBSCertificate, so all encoding variations
// should be captured. This test tries to exercise the cache's effects on
// signature verification. In reality, the cache is barely load-bearing. We now
// reject most non-DER inputs, and `X509_NAME` also saves its encoding. Still,
// the test ensures this remains the case.
TEST(X509Test, VerifyUnusualTBSCert) {
  UniquePtr<EVP_PKEY> key =
      PrivateKeyFromPEM(GetTestData("crypto/x509/test/unusual_tbs_key.pem"));
  ASSERT_TRUE(key);
  // The TBSCertificates were made with https://github.com/google/der-ascii.
  // crypto/x509/test/make_unusual_tbs.go then filled in valid signatures.
  const char *kPaths[] = {
      // Non-canonical encoding of TRUE in the critical bit.
      // TODO(crbug.com/442221114): The parser should reject this.
      "crypto/x509/test/unusual_tbs_critical_ber.pem",
      // A FALSE critical bit is encoded instead of omitted as DEFAULT.
      // TODO(crbug.com/442221114): The parser should reject this.
      "crypto/x509/test/unusual_tbs_critical_false_not_omitted.pem",
      // Empty extension instead of omitting the entire field.
      // TODO(crbug.com/442221114): The parser should reject this.
      "crypto/x509/test/unusual_tbs_empty_extension_not_omitted.pem",
      // ecdsa-with-SHA256 AlgorithmIdentifier parameters are NULL instead of
      // omitted. We accept this due to b/167375496.
      "crypto/x509/test/unusual_tbs_null_sigalg_param.pem",
      // Deprecated subject and issuer unique IDs are present. This is valid,
      // but rarely exercised.
      "crypto/x509/test/unusual_tbs_uid_both.pem",
      "crypto/x509/test/unusual_tbs_uid_issuer.pem",
      "crypto/x509/test/unusual_tbs_uid_subject.pem",
      // A v1 version is explicit encoded instead of omitted as DEFAULT.
      // TODO(crbug.com/42290225): The parser should reject this.
      "crypto/x509/test/unusual_tbs_v1_not_omitted.pem",
      // Within a RelativeDistinguishedName, attributes should be sorted in
      // canonical SET OF order. These are inverted.
      // TODO(crbug.com/42290219): The parser should reject this.
      "crypto/x509/test/unusual_tbs_wrong_attribute_order.pem",
  };
  for (const char *path : kPaths) {
    SCOPED_TRACE(path);
    UniquePtr<X509> cert = CertFromPEM(GetTestData(path));
    ASSERT_TRUE(cert);
    EXPECT_TRUE(X509_verify(cert.get(), key.get()));
  }
}

TEST(X509Test, TrailingDataX509) {
  UniquePtr<X509> cert(CertFromPEM(kLeafPEM));
  uint8_t *der = nullptr;
  int len = i2d_X509(cert.get(), &der);
  ASSERT_GT(len, 0);
  UniquePtr<uint8_t> free_der(der);

  bool ok =
      TestDERTrailingData(Span(der, len), [](Span<const uint8_t> in, size_t n) {
        SCOPED_TRACE(n);
        const uint8_t *p = in.data();
        UniquePtr<X509> parsed(d2i_X509(nullptr, &p, in.size()));
        EXPECT_FALSE(parsed);
      });
  EXPECT_TRUE(ok);
}

TEST(X509Test, TrailingDataCRL) {
  UniquePtr<X509_CRL> crl(CRLFromPEM(kRevokedCRL));
  uint8_t *der = nullptr;
  int len = i2d_X509_CRL(crl.get(), &der);
  ASSERT_GT(len, 0);
  UniquePtr<uint8_t> free_der(der);

  bool ok =
      TestDERTrailingData(Span(der, len), [](Span<const uint8_t> in, size_t n) {
        SCOPED_TRACE(n);
        const uint8_t *p = in.data();
        UniquePtr<X509_CRL> parsed(d2i_X509_CRL(nullptr, &p, in.size()));
        EXPECT_FALSE(parsed);
      });
  EXPECT_TRUE(ok);
}

TEST(X509Test, TrailingDataCSR) {
  UniquePtr<X509_REQ> csr(CSRFromPEM(kTestCSR));
  uint8_t *der = nullptr;
  int len = i2d_X509_REQ(csr.get(), &der);
  ASSERT_GT(len, 0);
  UniquePtr<uint8_t> free_der(der);

  bool ok =
      TestDERTrailingData(Span(der, len), [](Span<const uint8_t> in, size_t n) {
        SCOPED_TRACE(n);
        const uint8_t *p = in.data();
        UniquePtr<X509_REQ> parsed(d2i_X509_REQ(nullptr, &p, in.size()));
        EXPECT_FALSE(parsed);
      });
  EXPECT_TRUE(ok);
}

TEST(X509Test, NonDefaultKeyType) {
  // Parse an RSA-PSS key. This key type is not enabled by default.
  std::string pkcs8_str =
      GetTestData("crypto/x509/test/rsa_pss_sha256_key.pk8");
  auto pkcs8 = StringAsBytes(pkcs8_str);
  const EVP_PKEY_ALG *const alg = EVP_pkey_rsa_pss_sha256();
  UniquePtr<EVP_PKEY> pkey(
      EVP_PKEY_from_private_key_info(pkcs8.data(), pkcs8.size(), &alg, 1));
  ASSERT_TRUE(pkey);
  EXPECT_EQ(EVP_PKEY_id(pkey.get()), EVP_PKEY_RSA_PSS);

  // It should be possible to use `pkey` to make a certificate.
  UniquePtr<X509> cert =
      MakeTestCert("Test Issuer", "Test Subject", pkey.get(), /*is_ca=*/false);
  ASSERT_TRUE(cert);
  ASSERT_TRUE(X509_sign(cert.get(), pkey.get(), EVP_sha256()));

  // Verify the signature with `pkey`.
  EXPECT_TRUE(X509_verify(cert.get(), pkey.get()));

#if 1
  // TODO(crbug.com/42290364): This does not currently work, but it should.
  EXPECT_FALSE(X509_get0_pubkey(cert.get()));
#else
  // The public key can be extracted from `cert`.
  const EVP_PKEY *cert_pkey = X509_get0_pubkey(cert.get());
  ASSERT_TRUE(cert_pkey);
  EXPECT_EQ(EVP_PKEY_eq(pkey.get(), cert_pkey), 1);
  // `X509_check_private_key` should work.
  EXPECT_EQ(X509_check_private_key(cert.get(), pkey.get()), 1);
#endif

  // The resulting certificate can be serialized and re-parsed.
  UniquePtr<X509> reparsed = ReencodeCertificate(cert.get());
  ASSERT_TRUE(reparsed);

  // RSA-PSS is off by default, so parsing certificates anew with `d2i_X509`
  // will not enable off-by-default algorithms.
  EXPECT_FALSE(X509_get0_pubkey(reparsed.get()));
  EXPECT_EQ(X509_check_private_key(reparsed.get(), pkey.get()), 0);

  // Reparsing with RSA-PSS enabled does enable it.
  UniquePtr<X509> cert_with_key =
      ReencodeCertificateWithAlgorithms(cert.get(), Span(&alg, 1));
  ASSERT_TRUE(cert_with_key);
  // The public key can be extracted from `cert`.
  const EVP_PKEY *cert_pkey = X509_get0_pubkey(cert_with_key.get());
  ASSERT_TRUE(cert_pkey);
  EXPECT_EQ(EVP_PKEY_eq(pkey.get(), cert_pkey), 1);
  // `X509_check_private_key` should work.
  EXPECT_EQ(X509_check_private_key(cert_with_key.get(), pkey.get()), 1);

  // Verifying a certificate chain using `EVP_PKEY_RSA_PSS` should work as long
  // as all CA certificates have the key available. The end-entity key is not
  // checked.
  UniquePtr<X509> root =
      MakeTestCert("Test Issuer", "Test Issuer", pkey.get(), /*is_ca=*/true);
  ASSERT_TRUE(root);
  ASSERT_TRUE(X509_sign(root.get(), pkey.get(), EVP_sha256()));
  root = ReencodeCertificate(root.get());
  ASSERT_TRUE(root);
  UniquePtr<X509> root_with_key =
      ReencodeCertificateWithAlgorithms(root.get(), Span(&alg, 1));
  ASSERT_TRUE(root_with_key);
  EXPECT_EQ(X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY,
            Verify(cert.get(), /*roots=*/{root.get()},
                   /*intermediates=*/{}, /*crls=*/{}));
  EXPECT_EQ(X509_V_OK, Verify(cert.get(), /*roots=*/{root_with_key.get()},
                              /*intermediates=*/{}, /*crls=*/{}));
  EXPECT_EQ(X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY,
            Verify(cert_with_key.get(), /*roots=*/{root.get()},
                   /*intermediates=*/{}, /*crls=*/{}));
  EXPECT_EQ(X509_V_OK,
            Verify(cert_with_key.get(), /*roots=*/{root_with_key.get()},
                   /*intermediates=*/{}, /*crls=*/{}));
}

// Test that no-op self-assignments on `X509` fields work.
TEST(X509Test, SelfAssignFields) {
  // Test with an RSA key, so that the signature algorithm contains an explicit
  // NULL parameter (i.e. a non-nullptr `ASN1_TYPE` containing an ASN.1 NULL
  // value), rather than an omitted parameter (i.e. a nullptr `ASN1_TYPE`). This
  // exercises `X509_set1_signature_algo` better.
  UniquePtr<EVP_PKEY> key = PrivateKeyFromPEM(kRSAKey);
  ASSERT_TRUE(key);
  UniquePtr<X509> cert =
      MakeTestCert("Issuer", "Subject", key.get(), /*is_ca=*/true);
  EXPECT_TRUE(X509_sign(cert.get(), key.get(), EVP_sha256()));

  EXPECT_TRUE(
      X509_set_issuer_name(cert.get(), X509_get_issuer_name(cert.get())));
  const X509_NAME *issuer = X509_get_issuer_name(cert.get());
  EXPECT_EQ(X509_NAME_entry_count(issuer), 1);
  const X509_NAME_ENTRY *entry = X509_NAME_get_entry(issuer, 0);
  EXPECT_EQ(OBJ_obj2nid(X509_NAME_ENTRY_get_object(entry)), NID_commonName);
  EXPECT_EQ("Issuer", ASN1StringAsView(X509_NAME_ENTRY_get_data(entry)));

  EXPECT_TRUE(
      X509_set_subject_name(cert.get(), X509_get_subject_name(cert.get())));
  const X509_NAME *subject = X509_get_subject_name(cert.get());
  EXPECT_EQ(X509_NAME_entry_count(subject), 1);
  entry = X509_NAME_get_entry(subject, 0);
  EXPECT_EQ(OBJ_obj2nid(X509_NAME_ENTRY_get_object(entry)), NID_commonName);
  EXPECT_EQ("Subject", ASN1StringAsView(X509_NAME_ENTRY_get_data(entry)));

  std::string not_before_old(ASN1StringAsView(X509_get0_notBefore(cert.get())));
  EXPECT_TRUE(X509_set1_notBefore(cert.get(), X509_get0_notBefore(cert.get())));
  EXPECT_EQ(ASN1StringAsView(X509_get0_notBefore(cert.get())), not_before_old);

  std::string not_after_old(ASN1StringAsView(X509_get0_notAfter(cert.get())));
  EXPECT_TRUE(X509_set1_notAfter(cert.get(), X509_get0_notAfter(cert.get())));
  EXPECT_EQ(ASN1StringAsView(X509_get0_notAfter(cert.get())), not_after_old);

  long serial_old = ASN1_INTEGER_get(X509_get0_serialNumber(cert.get()));
  EXPECT_TRUE(
      X509_set_serialNumber(cert.get(), X509_get0_serialNumber(cert.get())));
  EXPECT_EQ(ASN1_INTEGER_get(X509_get0_serialNumber(cert.get())), serial_old);

  // X509_set1_signature_algo sets both the TBSCertificate and Certificate copy
  // of the signature algorithm.
  EXPECT_TRUE(
      X509_set1_signature_algo(cert.get(), X509_get0_tbs_sigalg(cert.get())));
  const ASN1_OBJECT *obj;
  int param_type;
  X509_ALGOR_get0(&obj, &param_type, /*out_param_value=*/nullptr,
                  X509_get0_tbs_sigalg(cert.get()));
  EXPECT_EQ(OBJ_obj2nid(obj), NID_sha256WithRSAEncryption);
  EXPECT_EQ(param_type, V_ASN1_NULL);

  const X509_ALGOR *alg;
  X509_get0_signature(nullptr, &alg, cert.get());
  EXPECT_TRUE(X509_set1_signature_algo(cert.get(), alg));
  X509_get0_signature(nullptr, &alg, cert.get());
  X509_ALGOR_get0(&obj, &param_type, /*out_param_value=*/nullptr, alg);
  EXPECT_EQ(OBJ_obj2nid(obj), NID_sha256WithRSAEncryption);
  EXPECT_EQ(param_type, V_ASN1_NULL);
}

TEST(X509Test, X509StoreGet1IssuerMultipleMatches) {
  // `kLeafPEM` is signed by `kIntermediatePEM`.
  UniquePtr<X509> cert = CertFromPEM(kLeafPEM);
  ASSERT_TRUE(cert);

  // Get an intermediate certificate that will match `cert`.
  UniquePtr<X509> issuer_ok = CertFromPEM(kIntermediatePEM);
  ASSERT_TRUE(issuer_ok);

  // Make certificates with the same issuer but the wrong SKID. They must be
  // signed by *some* key, but it doesn't matter which.
  UniquePtr<EVP_PKEY> key = PrivateKeyFromPEM(kRSAKey);
  ASSERT_TRUE(key);
  auto make_wrong_skid = [&](Span<const uint8_t> skid) -> UniquePtr<X509> {
    UniquePtr<X509> ret(X509_dup(issuer_ok.get()));
    if (ret == nullptr) {
      return nullptr;
    }
    X509_EXTENSION_free(X509_delete_ext(
        ret.get(),
        X509_get_ext_by_NID(ret.get(), NID_subject_key_identifier, -1)));
    if (!AddSubjectKeyIdentifier(ret.get(), skid) ||
        !X509_sign(ret.get(), key.get(), EVP_sha256())) {
      return nullptr;
    }
    return ret;
  };

  // Find an unrelated certificate that sorts _before_ the others.
  // "O=BoringSSL TESTING, CN=Root CA" sorts before "O=BoringSSL TESTING,
  // CN=Intermediate CA" because it is _shorter_. See `X509_NAME_cmp`.
  UniquePtr<X509> unrelated_before = CertFromPEM(kRootCAPEM);
  ASSERT_TRUE(unrelated_before);

  // Create a store, adding `unrelated_before`, `issuer_ok`, and several
  // certificates with the right name and wrong SKID.
  UniquePtr<X509_STORE> store(X509_STORE_new());
  ASSERT_TRUE(store);
  ASSERT_TRUE(X509_STORE_add_cert(store.get(), unrelated_before.get()));
  for (uint8_t i = 0; i < 64; i++) {
    uint8_t skid[1] = {i};
    UniquePtr<X509> issuer_wrong = make_wrong_skid(skid);
    ASSERT_TRUE(issuer_wrong);
    ASSERT_TRUE(X509_STORE_add_cert(store.get(), issuer_wrong.get()));
  }
  ASSERT_TRUE(X509_STORE_add_cert(store.get(), issuer_ok.get()));
  for (uint8_t i = 64; i < 128; i++) {
    uint8_t skid[1] = {i};
    UniquePtr<X509> issuer_wrong = make_wrong_skid(skid);
    ASSERT_TRUE(issuer_wrong);
    ASSERT_TRUE(X509_STORE_add_cert(store.get(), issuer_wrong.get()));
  }

  // Verify a certificate using the store. It should find the correct issuer by
  // matching SKID.
  UniquePtr<X509_STORE_CTX> ctx(X509_STORE_CTX_new());
  ASSERT_TRUE(ctx);
  ASSERT_TRUE(X509_STORE_CTX_init(ctx.get(), store.get(), cert.get(), nullptr));
  X509_STORE_CTX_set_time_posix(ctx.get(), /*flags=*/0, kReferenceTime);
  EXPECT_EQ(X509_verify_cert(ctx.get()), 1)
      << "Certificate verification failed: "
      << X509_STORE_CTX_get_error(ctx.get());

  // X509_STORE_CTX_get1_issuer, which takes the certificate and not just the
  // issuer name, should also find the one with a matching SKID.
  X509 *found_issuer = nullptr;
  int get1_ret =
      X509_STORE_CTX_get1_issuer(&found_issuer, ctx.get(), cert.get());
  ASSERT_EQ(1, get1_ret);
  ASSERT_TRUE(found_issuer);
  EXPECT_EQ(0, X509_cmp(found_issuer, issuer_ok.get()));
  X509_free(found_issuer);
}

TEST(X509Test, CheckPrivateKey) {
  UniquePtr<EVP_PKEY> p256(EVP_PKEY_generate_from_alg(EVP_pkey_ec_p256()));
  ASSERT_TRUE(p256);
  UniquePtr<EVP_PKEY> p256_2(EVP_PKEY_generate_from_alg(EVP_pkey_ec_p256()));
  ASSERT_TRUE(p256_2);
  UniquePtr<EVP_PKEY> p384(EVP_PKEY_generate_from_alg(EVP_pkey_ec_p384()));
  ASSERT_TRUE(p384);
  UniquePtr<EVP_PKEY> rsa(EVP_PKEY_generate_from_alg(EVP_pkey_rsa()));
  ASSERT_TRUE(rsa);

  UniquePtr<X509> cert = MakeTestCert("Issuer", "Subject", p256.get(), false);
  ASSERT_TRUE(cert);
  ASSERT_TRUE(X509_sign(cert.get(), p256.get(), EVP_sha256()));

  EXPECT_EQ(X509_check_private_key(cert.get(), p256.get()), 1);
  EXPECT_EQ(X509_check_private_key(cert.get(), p256_2.get()), 0);
  EXPECT_TRUE(
      ErrorEquals(ERR_get_error(), ERR_LIB_X509, X509_R_KEY_VALUES_MISMATCH));
  EXPECT_EQ(X509_check_private_key(cert.get(), p384.get()), 0);
  EXPECT_TRUE(
      ErrorEquals(ERR_get_error(), ERR_LIB_X509, X509_R_KEY_VALUES_MISMATCH));
  EXPECT_EQ(X509_check_private_key(cert.get(), rsa.get()), 0);
  EXPECT_TRUE(
      ErrorEquals(ERR_get_error(), ERR_LIB_X509, X509_R_KEY_TYPE_MISMATCH));

  UniquePtr<X509_REQ> csr = CSRFromPEM(kTestCSR);
  ASSERT_TRUE(csr);
  ASSERT_TRUE(X509_REQ_set_pubkey(csr.get(), p256.get()));
  ASSERT_TRUE(X509_REQ_sign(csr.get(), p256.get(), EVP_sha256()));

  EXPECT_EQ(X509_REQ_check_private_key(csr.get(), p256.get()), 1);
  EXPECT_EQ(X509_REQ_check_private_key(csr.get(), p256_2.get()), 0);
  EXPECT_TRUE(
      ErrorEquals(ERR_get_error(), ERR_LIB_X509, X509_R_KEY_VALUES_MISMATCH));
  EXPECT_EQ(X509_REQ_check_private_key(csr.get(), p384.get()), 0);
  EXPECT_TRUE(
      ErrorEquals(ERR_get_error(), ERR_LIB_X509, X509_R_KEY_VALUES_MISMATCH));
  EXPECT_EQ(X509_REQ_check_private_key(csr.get(), rsa.get()), 0);
  EXPECT_TRUE(
      ErrorEquals(ERR_get_error(), ERR_LIB_X509, X509_R_KEY_TYPE_MISMATCH));
}

TEST(X509Test, GetEmail) {
  // A certificate with no emails.
  UniquePtr<EVP_PKEY> p256(EVP_PKEY_generate_from_alg(EVP_pkey_ec_p256()));
  ASSERT_TRUE(p256);
  UniquePtr<X509> cert = MakeTestCert("Issuer", "Subject", p256.get(), false);
  ASSERT_TRUE(cert);
  ASSERT_TRUE(X509_sign(cert.get(), p256.get(), EVP_sha256()));
  EXPECT_EQ(nullptr, X509_get1_email(cert.get()));

  // A CSR with no emails.
  UniquePtr<X509_REQ> req(X509_REQ_new());
  ASSERT_TRUE(req);
  ASSERT_TRUE(X509_REQ_set_pubkey(req.get(), p256.get()));
  ASSERT_TRUE(X509_REQ_sign(req.get(), p256.get(), EVP_sha256()));
  EXPECT_EQ(nullptr, X509_REQ_get1_email(req.get()));

  // Prepare many emails.
  constexpr size_t kCount = 5000;
  UniquePtr<X509_NAME> subject(X509_NAME_new());
  ASSERT_TRUE(subject);
  UniquePtr<GENERAL_NAMES> sans(GENERAL_NAMES_new());
  ASSERT_TRUE(sans);
  std::vector<std::string> expected;
  for (size_t i = 0; i < kCount; i++) {
    bool duplicate = i % 3 == 0;
    bool add_to_both = i % 5 == 0;
    bool add_to_subject = add_to_both || i % 2 == 0;
    bool add_to_sans = add_to_both || i % 2 == 1;

    char email[256];
    snprintf(email, sizeof(email), "test%zu@example.com", i);
    std::string_view email_sv = email;
    Span<const uint8_t> email_bytes = StringAsBytes(email);
    if (i == 0) {
      // Test with an embedded NUL. This string should be discarded.
      email[4] = '\0';
    } else {
      expected.push_back(email);
    }

    for (int dup = 0; dup < (duplicate ? 1 : 2); dup++) {
      if (add_to_subject) {
        ASSERT_TRUE(X509_NAME_add_entry_by_NID(
            subject.get(), NID_pkcs9_emailAddress, MBSTRING_UTF8,
            email_bytes.data(), email_bytes.size(), /*loc=*/-1, /*set=*/-1));
      }
      if (add_to_sans) {
        UniquePtr<GENERAL_NAME> san = MakeGeneralName(GEN_EMAIL, email_sv);
        ASSERT_TRUE(san);
        ASSERT_TRUE(PushToStack(sans.get(), std::move(san)));
      }
    }
  }

  // A certificate with many emails.
  {
    cert = MakeTestCert("Issuer", "Subject", p256.get(), false);
    ASSERT_TRUE(cert);
    ASSERT_TRUE(X509_set_subject_name(cert.get(), subject.get()));
    ASSERT_TRUE(X509_add1_ext_i2d(cert.get(), NID_subject_alt_name, sans.get(),
                                  /*crit=*/0, /*flags=*/0));
    ASSERT_TRUE(X509_sign(cert.get(), p256.get(), EVP_sha256()));

    UniquePtr<STACK_OF(OPENSSL_STRING)> emails(X509_get1_email(cert.get()));
    ASSERT_TRUE(emails);
    std::vector<std::string> actual;
    for (const char *email : emails.get()) {
      actual.push_back(email);
    }

    // The output order is undefined.
    std::sort(expected.begin(), expected.end());
    std::sort(actual.begin(), actual.end());
    EXPECT_EQ(actual, expected);
  }

  // A CSR with many emails.
  {
    req.reset(X509_REQ_new());
    ASSERT_TRUE(req);
    ASSERT_TRUE(X509_REQ_set_subject_name(req.get(), subject.get()));
    ASSERT_TRUE(X509_REQ_set_pubkey(req.get(), p256.get()));
    STACK_OF(X509_EXTENSION) *exts_raw = nullptr;
    ASSERT_TRUE(X509V3_add1_i2d(&exts_raw, NID_subject_alt_name, sans.get(),
                                /*crit=*/0, X509V3_ADD_APPEND));
    UniquePtr<STACK_OF(X509_EXTENSION)> exts(exts_raw);
    ASSERT_TRUE(X509_REQ_add_extensions(req.get(), exts.get()));
    ASSERT_TRUE(X509_REQ_sign(req.get(), p256.get(), EVP_sha256()));

    UniquePtr<STACK_OF(OPENSSL_STRING)> emails(X509_REQ_get1_email(req.get()));
    ASSERT_TRUE(emails);
    std::vector<std::string> actual;
    for (const char *email : emails.get()) {
      actual.push_back(email);
    }

    // The output order is undefined.
    std::sort(expected.begin(), expected.end());
    std::sort(actual.begin(), actual.end());
    EXPECT_EQ(actual, expected);
  }
}

TEST(X509Test, GetOCSP) {
  // A certificate with no OCSP URIs.
  UniquePtr<EVP_PKEY> p256(EVP_PKEY_generate_from_alg(EVP_pkey_ec_p256()));
  ASSERT_TRUE(p256);
  UniquePtr<X509> cert = MakeTestCert("Issuer", "Subject", p256.get(), false);
  ASSERT_TRUE(cert);
  ASSERT_TRUE(X509_sign(cert.get(), p256.get(), EVP_sha256()));
  EXPECT_EQ(nullptr, X509_get1_ocsp(cert.get()));

  // Make a certificate with many OCSP URIs.
  constexpr size_t kCount = 5000;
  UniquePtr<AUTHORITY_INFO_ACCESS> aia(AUTHORITY_INFO_ACCESS_new());
  ASSERT_TRUE(aia);
  std::vector<std::string> expected;
  for (size_t i = 0; i < kCount; i++) {
    bool duplicate = i % 3 == 0;
    bool is_ocsp = i % 5 != 0;
    char uri[256];
    snprintf(uri, sizeof(uri), "http://test%zu.example.com/", i);
    std::string_view uri_sv = uri;
    if (i == 0) {
      // Test with an embedded NUL. This string should be discarded.
      uri[11] = '\0';
    } else if (is_ocsp) {
      expected.push_back(uri);
    }

    for (int dup = 0; dup < (duplicate ? 1 : 2); dup++) {
      UniquePtr<ACCESS_DESCRIPTION> ad(ACCESS_DESCRIPTION_new());
      ASSERT_TRUE(ad);
      ad->method = OBJ_nid2obj(is_ocsp ? NID_ad_OCSP : NID_ad_ca_issuers);
      GENERAL_NAME_free(ad->location);
      ad->location = MakeGeneralName(GEN_URI, uri_sv).release();
      ASSERT_TRUE(ad->location);
      ASSERT_TRUE(PushToStack(aia.get(), std::move(ad)));
    }
  }

  cert = MakeTestCert("Issuer", "Subject", p256.get(), false);
  ASSERT_TRUE(cert);
  ASSERT_TRUE(X509_add1_ext_i2d(cert.get(), NID_info_access, aia.get(),
                                /*crit=*/0, /*flags=*/0));
  ASSERT_TRUE(X509_sign(cert.get(), p256.get(), EVP_sha256()));

  UniquePtr<STACK_OF(OPENSSL_STRING)> ocsps(X509_get1_ocsp(cert.get()));
  ASSERT_TRUE(ocsps);
  std::vector<std::string> actual;
  for (const char *ocsp : ocsps.get()) {
    actual.push_back(ocsp);
  }

  // The output order is undefined.
  std::sort(expected.begin(), expected.end());
  std::sort(actual.begin(), actual.end());
  EXPECT_EQ(actual, expected);
}

struct CertChainItem {
  bool self_issued;
  std::optional<int64_t> pathlen;
};

static std::optional<int> VerifyChain(
    std::initializer_list<CertChainItem> items) {
  std::vector<bssl::UniquePtr<X509>> intermediates;

  std::vector<UniquePtr<EVP_PKEY>> keys;
  for (size_t k = 0; k < items.size(); ++k) {
    UniquePtr<EVP_PKEY> key(EVP_PKEY_generate_from_alg(EVP_pkey_ec_p256()));
    if (key == nullptr) {
      return std::nullopt;
    }
    keys.push_back(std::move(key));
  }

  bssl::UniquePtr<X509> leaf = nullptr;

  size_t name_idx = 0;
  size_t key_idx = 0;
  for (const auto &item : items) {
    std::string subject_name = std::to_string(name_idx);
    if (!item.self_issued) {
      ++name_idx;
    }
    std::string issuer_name = std::to_string(name_idx);

    size_t subject_key_idx = key_idx;
    if (key_idx < items.size() - 1) {
      ++key_idx;
    }
    size_t issuer_key_idx = key_idx;

    EVP_PKEY *subject_key = keys[subject_key_idx].get();
    EVP_PKEY *issuer_key = keys[issuer_key_idx].get();

    bssl::UniquePtr<X509> cert(MakeTestCert(
        issuer_name, subject_name, subject_key, /*is_ca=*/true, item.pathlen));
    uint8_t skid = static_cast<uint8_t>(subject_key_idx);
    uint8_t akid = static_cast<uint8_t>(issuer_key_idx);
    if (cert == nullptr || !AddSubjectKeyIdentifier(cert.get(), {&skid, 1}) ||
        !AddAuthorityKeyIdentifier(cert.get(), {&akid, 1}) ||
        !X509_sign(cert.get(), issuer_key, EVP_sha256())) {
      return std::nullopt;
    }
    if (leaf == nullptr) {
      // The first cert in the list is the leaf.
      leaf = std::move(cert);
    } else {
      // All else gets into the chain for now.
      intermediates.emplace_back(std::move(cert));
    }
  }

  // The last cert shall be considered the root.
  bssl::UniquePtr<X509> root = std::move(intermediates.back());
  intermediates.pop_back();

  std::vector<X509 *> intermediate_ptrs = {};
  for (const auto &intermediate : intermediates) {
    intermediate_ptrs.push_back(intermediate.get());
  }
  return Verify(leaf.get(), {root.get()}, intermediate_ptrs, {}, /*flags=*/0);
}

TEST(X509Test, PathLenNormalUnconstrained) {
  EXPECT_EQ(X509_V_OK,
            VerifyChain({{/*self_issued=*/false, /*pathlen=*/std::nullopt},
                         {/*self_issued=*/false, /*pathlen=*/std::nullopt},
                         {/*self_issued=*/false, /*pathlen=*/std::nullopt},
                         {/*self_issued=*/false, /*pathlen=*/std::nullopt},
                         {/*self_issued=*/true, /*pathlen=*/std::nullopt}}));
}

TEST(X509Test, PathLenNormal) {
  EXPECT_EQ(X509_V_OK, VerifyChain({{/*self_issued=*/false, /*pathlen=*/0},
                                    {/*self_issued=*/false, /*pathlen=*/0},
                                    {/*self_issued=*/false, /*pathlen=*/1},
                                    {/*self_issued=*/false, /*pathlen=*/2},
                                    {/*self_issued=*/true, /*pathlen=*/3}}));
  EXPECT_EQ(X509_V_ERR_PATH_LENGTH_EXCEEDED,
            VerifyChain({{/*self_issued=*/false, /*pathlen=*/0},
                         {/*self_issued=*/false, /*pathlen=*/0},
                         {/*self_issued=*/false, /*pathlen=*/0},
                         {/*self_issued=*/false, /*pathlen=*/2},
                         {/*self_issued=*/true, /*pathlen=*/3}}));
  EXPECT_EQ(X509_V_ERR_PATH_LENGTH_EXCEEDED,
            VerifyChain({{/*self_issued=*/false, /*pathlen=*/0},
                         {/*self_issued=*/false, /*pathlen=*/0},
                         {/*self_issued=*/false, /*pathlen=*/1},
                         {/*self_issued=*/false, /*pathlen=*/1},
                         {/*self_issued=*/true, /*pathlen=*/3}}));
  EXPECT_EQ(X509_V_OK,  // Path length on trust anchor is ignored.
            VerifyChain({{/*self_issued=*/false, /*pathlen=*/0},
                         {/*self_issued=*/false, /*pathlen=*/0},
                         {/*self_issued=*/false, /*pathlen=*/1},
                         {/*self_issued=*/false, /*pathlen=*/2},
                         {/*self_issued=*/true, /*pathlen=*/2}}));
}

TEST(X509Test, PathLenSelfIssuedNotCountedButStillVerified) {
  EXPECT_EQ(X509_V_OK, VerifyChain({{/*self_issued=*/false, /*pathlen=*/0},
                                    {/*self_issued=*/false, /*pathlen=*/0},
                                    {/*self_issued=*/true, /*pathlen=*/1},
                                    {/*self_issued=*/false, /*pathlen=*/1},
                                    {/*self_issued=*/true, /*pathlen=*/2}}));
  EXPECT_EQ(X509_V_ERR_PATH_LENGTH_EXCEEDED,
            VerifyChain({{/*self_issued=*/false, /*pathlen=*/0},
                         {/*self_issued=*/false, /*pathlen=*/0},
                         {/*self_issued=*/true, /*pathlen=*/0},
                         {/*self_issued=*/false, /*pathlen=*/1},
                         {/*self_issued=*/true, /*pathlen=*/2}}));
  EXPECT_EQ(X509_V_ERR_PATH_LENGTH_EXCEEDED,
            VerifyChain({{/*self_issued=*/false, /*pathlen=*/0},
                         {/*self_issued=*/false, /*pathlen=*/0},
                         {/*self_issued=*/true, /*pathlen=*/1},
                         {/*self_issued=*/false, /*pathlen=*/0},
                         {/*self_issued=*/true, /*pathlen=*/2}}));
  EXPECT_EQ(X509_V_OK,  // Path length on trust anchor is ignored.
            VerifyChain({{/*self_issued=*/false, /*pathlen=*/0},
                         {/*self_issued=*/false, /*pathlen=*/0},
                         {/*self_issued=*/true, /*pathlen=*/1},
                         {/*self_issued=*/false, /*pathlen=*/1},
                         {/*self_issued=*/true, /*pathlen=*/1}}));
}

}  // namespace
BSSL_NAMESPACE_END