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boringssl/boringssl.git/06197721e8a93467e565d54dbec7f65ac97b13bf/./ssl/internal.h
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// Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
// Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved.
// Copyright 2005 Nokia. All rights reserved.
//
// 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.
#ifndef OPENSSL_HEADER_SSL_INTERNAL_H
#define OPENSSL_HEADER_SSL_INTERNAL_H
#include <openssl/base.h>
#include <stdlib.h>
#include <algorithm>
#include <atomic>
#include <bitset>
#include <initializer_list>
#include <limits>
#include <new>
#include <optional>
#include <string_view>
#include <type_traits>
#include <utility>
#include <variant>
#include <openssl/aead.h>
#include <openssl/curve25519.h>
#include <openssl/err.h>
#include <openssl/hpke.h>
#include <openssl/mem.h>
#include <openssl/span.h>
#include <openssl/ssl.h>
#include <openssl/stack.h>
#include "../crypto/err/internal.h"
#include "../crypto/internal.h"
#include "../crypto/lhash/internal.h"
#include "../crypto/mem_internal.h"
#include "../crypto/spake2plus/internal.h"
#if defined(OPENSSL_WINDOWS)
// Windows defines struct timeval in winsock2.h.
#include <winsock2.h>
#else
#include <sys/time.h>
#endif
DECLARE_OPAQUE_STRUCT(ssl_credential_st, SSLCredential)
DECLARE_OPAQUE_STRUCT(ssl_ctx_st, SSLContext)
DECLARE_OPAQUE_STRUCT(ssl_ech_keys_st, SSLECHKeys)
BSSL_NAMESPACE_BEGIN
struct SSL_CONFIG;
struct SSL_HANDSHAKE;
struct SSL_PROTOCOL_METHOD;
struct SSL_X509_METHOD;
// C++ utilities.
// An MRUQueue maintains a queue of up to `N` objects of type `T`. If the queue
// is at capacity, adding to the queue pops the least recently added element.
template <typename T, size_t N>
class MRUQueue {
public:
static constexpr bool kAllowUniquePtr = true;
MRUQueue() = default;
// If we ever need to make this type movable, we could. (The defaults almost
// work except we need `start_` to be reset when moved-from.)
MRUQueue(const MRUQueue &other) = delete;
MRUQueue &operator=(const MRUQueue &other) = delete;
bool empty() const { return size() == 0; }
size_t size() const { return storage_.size(); }
T &operator[](size_t i) {
BSSL_CHECK(i < size());
return storage_[(start_ + i) % N];
}
const T &operator[](size_t i) const {
return (*const_cast<MRUQueue *>(this))[i];
}
void Clear() {
storage_.clear();
start_ = 0;
}
void PushBack(T t) {
if (storage_.size() < N) {
assert(start_ == 0);
storage_.PushBack(std::move(t));
} else {
(*this)[0] = std::move(t);
start_ = (start_ + 1) % N;
}
}
private:
InplaceVector<T, N> storage_;
PackedSize<N> start_ = 0;
};
// GetAllNames helps to implement `*_get_all_*_names` style functions. It
// writes at most `max_out` string pointers to `out` and returns the number that
// it would have liked to have written. The strings written consist of
// `fixed_names_len` strings from `fixed_names` followed by `objects_len`
// strings taken by projecting `objects` through `name`.
template <typename T, typename Name, size_t S1, size_t S2>
inline size_t GetAllNames(const char **out, size_t max_out,
Span<const char *const, S1> fixed_names,
Name(T::*name), Span<const T, S2> objects) {
auto span = Span(out, max_out);
for (size_t i = 0; !span.empty() && i < fixed_names.size(); i++) {
span[0] = fixed_names[i];
span = span.subspan(1);
}
span = span.first(std::min(span.size(), objects.size()));
for (size_t i = 0; i < span.size(); i++) {
span[i] = objects[i].*name;
}
return fixed_names.size() + objects.size();
}
// Protocol versions.
//
// Due to DTLS's historical wire version differences, we maintain two notions of
// version.
//
// The "version" or "wire version" is the actual 16-bit value that appears on
// the wire. It uniquely identifies a version and is also used at API
// boundaries. The set of supported versions differs between TLS and DTLS. Wire
// versions are opaque values and may not be compared numerically.
//
// The "protocol version" identifies the high-level handshake variant being
// used. DTLS versions map to the corresponding TLS versions. Protocol versions
// are sequential and may be compared numerically.
// ssl_protocol_version_from_wire sets `*out` to the protocol version
// corresponding to wire version `version` and returns true. If `version` is not
// a valid TLS or DTLS version, it returns false.
//
// Note this simultaneously handles both DTLS and TLS. Use one of the
// higher-level functions below for most operations.
bool ssl_protocol_version_from_wire(uint16_t *out, uint16_t version);
// ssl_get_version_range sets `*out_min_version` and `*out_max_version` to the
// minimum and maximum enabled protocol versions, respectively.
bool ssl_get_version_range(const SSL_HANDSHAKE *hs, uint16_t *out_min_version,
uint16_t *out_max_version);
// ssl_supports_version returns whether `hs` supports `version`.
bool ssl_supports_version(const SSL_HANDSHAKE *hs, uint16_t version);
// ssl_method_supports_version returns whether `method` supports `version`.
bool ssl_method_supports_version(const SSL_PROTOCOL_METHOD *method,
uint16_t version);
// ssl_add_supported_versions writes the supported versions of `hs` to `cbb`, in
// decreasing preference order. The version list is filtered to those whose
// protocol version is at least `extra_min_version`.
bool ssl_add_supported_versions(const SSL_HANDSHAKE *hs, CBB *cbb,
uint16_t extra_min_version);
// ssl_negotiate_version negotiates a common version based on `hs`'s preferences
// and the peer preference list in `peer_versions`. On success, it returns true
// and sets `*out_version` to the selected version. Otherwise, it returns false
// and sets `*out_alert` to an alert to send.
bool ssl_negotiate_version(SSL_HANDSHAKE *hs, uint8_t *out_alert,
uint16_t *out_version, const CBS *peer_versions);
// ssl_has_final_version returns whether `ssl` has determined the final version.
// This may be used to distinguish the predictive 0-RTT version from the final
// one.
bool ssl_has_final_version(const SSL *ssl);
// ssl_protocol_version returns `ssl`'s protocol version. It is an error to
// call this function before the version is determined.
uint16_t ssl_protocol_version(const SSL *ssl);
// Cipher suites.
BSSL_NAMESPACE_END
struct ssl_cipher_st {
// name is the OpenSSL name for the cipher.
const char *name;
// standard_name is the IETF name for the cipher.
const char *standard_name;
// protocol_id is the cipher's two-byte protocol ID.
uint16_t protocol_id;
// algorithm_* determine the cipher suite. See constants below for the values.
uint32_t algorithm_mkey;
uint32_t algorithm_auth;
uint32_t algorithm_enc;
uint32_t algorithm_mac;
uint32_t algorithm_prf;
};
BSSL_NAMESPACE_BEGIN
// Bits for `algorithm_mkey` (key exchange algorithm).
#define SSL_kRSA 0x00000001u
#define SSL_kECDHE 0x00000002u
// SSL_kPSK is only set for plain PSK, not ECDHE_PSK.
#define SSL_kPSK 0x00000004u
#define SSL_kGENERIC 0x00000008u
// Bits for `algorithm_auth` (server authentication).
#define SSL_aRSA_SIGN 0x00000001u
#define SSL_aRSA_DECRYPT 0x00000002u
#define SSL_aECDSA 0x00000004u
// SSL_aPSK is set for both PSK and ECDHE_PSK.
#define SSL_aPSK 0x00000008u
#define SSL_aGENERIC 0x00000010u
#define SSL_aCERT (SSL_aRSA_SIGN | SSL_aRSA_DECRYPT | SSL_aECDSA)
// Bits for `algorithm_enc` (symmetric encryption).
#define SSL_3DES 0x00000001u
#define SSL_AES128 0x00000002u
#define SSL_AES256 0x00000004u
#define SSL_AES128GCM 0x00000008u
#define SSL_AES256GCM 0x00000010u
#define SSL_CHACHA20POLY1305 0x00000020u
#define SSL_AES (SSL_AES128 | SSL_AES256 | SSL_AES128GCM | SSL_AES256GCM)
// Bits for `algorithm_mac` (symmetric authentication).
#define SSL_SHA1 0x00000001u
#define SSL_SHA256 0x00000002u
// SSL_AEAD is set for all AEADs.
#define SSL_AEAD 0x00000004u
// Bits for `algorithm_prf` (handshake digest).
#define SSL_HANDSHAKE_MAC_DEFAULT 0x1
#define SSL_HANDSHAKE_MAC_SHA256 0x2
#define SSL_HANDSHAKE_MAC_SHA384 0x4
// SSL_MAX_MD_SIZE is size of the largest hash function used in TLS, SHA-384.
#define SSL_MAX_MD_SIZE 48
// An SSLCipherPreferenceList contains a list of SSL_CIPHERs with equal-
// preference groups. For TLS clients, the groups are moot because the server
// picks the cipher and groups cannot be expressed on the wire. However, for
// servers, the equal-preference groups allow the client's preferences to be
// partially respected. (This only has an effect with
// SSL_OP_CIPHER_SERVER_PREFERENCE).
//
// The equal-preference groups are expressed by grouping SSL_CIPHERs together.
// All elements of a group have the same priority: no ordering is expressed
// within a group.
//
// The values in `ciphers` are in one-to-one correspondence with
// `in_group_flags`. (That is, sk_SSL_CIPHER_num(ciphers) is the number of
// bytes in `in_group_flags`.) The bytes in `in_group_flags` are either 1, to
// indicate that the corresponding SSL_CIPHER is not the last element of a
// group, or 0 to indicate that it is.
//
// For example, if `in_group_flags` contains all zeros then that indicates a
// traditional, fully-ordered preference. Every SSL_CIPHER is the last element
// of the group (i.e. they are all in a one-element group).
//
// For a more complex example, consider:
// ciphers: A B C D E F
// in_group_flags: 1 1 0 0 1 0
//
// That would express the following, order:
//
// A E
// B -> D -> F
// C
struct SSLCipherPreferenceList {
static constexpr bool kAllowUniquePtr = true;
SSLCipherPreferenceList() = default;
~SSLCipherPreferenceList();
bool Init(UniquePtr<STACK_OF(SSL_CIPHER)> ciphers,
Span<const bool> in_group_flags);
bool Init(const SSLCipherPreferenceList &);
void Remove(const SSL_CIPHER *cipher);
UniquePtr<STACK_OF(SSL_CIPHER)> ciphers;
bool *in_group_flags = nullptr;
};
// AllCiphers returns an array of all supported ciphers, sorted by id.
Span<const SSL_CIPHER> AllCiphers();
// ssl_cipher_get_evp_aead sets `*out_aead` to point to the correct EVP_AEAD
// object for `cipher` protocol version `version`. It sets `*out_mac_secret_len`
// and `*out_fixed_iv_len` to the MAC key length and fixed IV length,
// respectively. The MAC key length is zero except for legacy block and stream
// ciphers. It returns true on success and false on error.
bool ssl_cipher_get_evp_aead(const EVP_AEAD **out_aead,
size_t *out_mac_secret_len,
size_t *out_fixed_iv_len, const SSL_CIPHER *cipher,
uint16_t version);
// ssl_get_handshake_digest returns the `EVP_MD` corresponding to `version` and
// `cipher`.
const EVP_MD *ssl_get_handshake_digest(uint16_t version,
const SSL_CIPHER *cipher);
// ssl_create_cipher_list evaluates `rule_str`. It sets `*out_cipher_list` to a
// newly-allocated `SSLCipherPreferenceList` containing the result. It returns
// true on success and false on failure. If `strict` is true, nonsense will be
// rejected. If false, nonsense will be silently ignored. An empty result is
// considered an error regardless of `strict`. `has_aes_hw` indicates if the
// list should be ordered based on having support for AES in hardware or not.
bool ssl_create_cipher_list(UniquePtr<SSLCipherPreferenceList> *out_cipher_list,
const bool has_aes_hw, const char *rule_str,
bool strict);
// ssl_cipher_auth_mask_for_key returns the mask of cipher `algorithm_auth`
// values suitable for use with `key` in TLS 1.2 and below. `sign_ok` indicates
// whether `key` may be used for signing.
uint32_t ssl_cipher_auth_mask_for_key(const EVP_PKEY *key, bool sign_ok);
// ssl_cipher_uses_certificate_auth returns whether `cipher` authenticates the
// server and, optionally, the client with a certificate.
bool ssl_cipher_uses_certificate_auth(const SSL_CIPHER *cipher);
// ssl_cipher_requires_server_key_exchange returns whether `cipher` requires a
// ServerKeyExchange message.
//
// This function may return false while still allowing `cipher` an optional
// ServerKeyExchange. This is the case for plain PSK ciphers.
bool ssl_cipher_requires_server_key_exchange(const SSL_CIPHER *cipher);
// ssl_cipher_get_record_split_len, for TLS 1.0 CBC mode ciphers, returns the
// length of an encrypted 1-byte record, for use in record-splitting. Otherwise
// it returns zero.
size_t ssl_cipher_get_record_split_len(const SSL_CIPHER *cipher);
// ssl_choose_tls13_cipher returns an `SSL_CIPHER` corresponding with the best
// available from `cipher_suites` compatible with `version` and `policy`. It
// returns NULL if there isn't a compatible cipher. `has_aes_hw` indicates if
// the choice should be made as if support for AES in hardware is available.
const SSL_CIPHER *ssl_choose_tls13_cipher(CBS cipher_suites, bool has_aes_hw,
uint16_t version,
enum ssl_compliance_policy_t policy);
// ssl_tls13_cipher_meets_policy returns true if `cipher_id` is acceptable given
// `policy`.
bool ssl_tls13_cipher_meets_policy(uint16_t cipher_id,
enum ssl_compliance_policy_t policy);
// ssl_cipher_is_deprecated returns true if `cipher` is deprecated.
OPENSSL_EXPORT bool ssl_cipher_is_deprecated(const SSL_CIPHER *cipher);
// Transcript layer.
// SSLTranscript maintains the handshake transcript as a combination of a
// buffer and running hash.
class SSLTranscript {
public:
explicit SSLTranscript(bool is_dtls);
~SSLTranscript();
SSLTranscript(SSLTranscript &&other) = default;
SSLTranscript &operator=(SSLTranscript &&other) = default;
// Init initializes the handshake transcript. If called on an existing
// transcript, it resets the transcript and hash. It returns true on success
// and false on failure.
bool Init();
// InitHash initializes the handshake hash based on the PRF and contents of
// the handshake transcript. Subsequent calls to `Update` will update the
// rolling hash. It returns one on success and zero on failure. It is an error
// to call this function after the handshake buffer is released. This may be
// called multiple times to change the hash function.
bool InitHash(uint16_t version, const SSL_CIPHER *cipher);
// UpdateForHelloRetryRequest resets the rolling hash with the
// HelloRetryRequest construction. It returns true on success and false on
// failure. It is an error to call this function before the handshake buffer
// is released.
bool UpdateForHelloRetryRequest();
// CopyToHashContext initializes `ctx` with `digest` and the data thus far in
// the transcript. It returns true on success and false on failure. If the
// handshake buffer is still present, `digest` may be any supported digest.
// Otherwise, `digest` must match the transcript hash.
bool CopyToHashContext(EVP_MD_CTX *ctx, const EVP_MD *digest) const;
Span<const uint8_t> buffer() const {
return Span(reinterpret_cast<const uint8_t *>(buffer_->data),
buffer_->length);
}
// FreeBuffer releases the handshake buffer. Subsequent calls to
// `Update` will not update the handshake buffer.
void FreeBuffer();
// DigestLen returns the length of the PRF hash.
size_t DigestLen() const;
// Digest returns the PRF hash. For TLS 1.1 and below, this is
// `EVP_md5_sha1`.
const EVP_MD *Digest() const;
// Update adds `in` to the handshake buffer and handshake hash, whichever is
// enabled. It returns true on success and false on failure.
bool Update(Span<const uint8_t> in);
// GetHash writes the handshake hash to `out` which must have room for at
// least `DigestLen` bytes. On success, it returns true and sets `*out_len` to
// the number of bytes written. Otherwise, it returns false.
bool GetHash(uint8_t *out, size_t *out_len) const;
// GetFinishedMAC computes the MAC for the Finished message into the bytes
// pointed by `out` and writes the number of bytes to `*out_len`. `out` must
// have room for `EVP_MAX_MD_SIZE` bytes. It returns true on success and false
// on failure.
bool GetFinishedMAC(uint8_t *out, size_t *out_len, const SSL_SESSION *session,
bool from_server) const;
private:
// HashBuffer initializes `ctx` to use `digest` and writes the contents of
// `buffer_` to `ctx`. If this SSLTranscript is for DTLS 1.3, the appropriate
// bytes in `buffer_` will be skipped when hashing the buffer.
bool HashBuffer(EVP_MD_CTX *ctx, const EVP_MD *digest) const;
// AddToBufferOrHash directly adds the contents of `in` to `buffer_` and/or
// `hash_`.
bool AddToBufferOrHash(Span<const uint8_t> in);
// buffer_, if non-null, contains the handshake transcript.
UniquePtr<BUF_MEM> buffer_;
// hash, if initialized with an `EVP_MD`, maintains the handshake hash.
ScopedEVP_MD_CTX hash_;
// is_dtls_ indicates whether this is a transcript for a DTLS connection.
bool is_dtls_ : 1;
// version_ contains the version for the connection (if known).
uint16_t version_ = 0;
};
// tls1_prf computes the PRF function for `ssl`. It fills `out`, using `secret`
// as the secret and `label` as the label. `seed1` and `seed2` are concatenated
// to form the seed parameter. It returns true on success and false on failure.
bool tls1_prf(const EVP_MD *digest, Span<uint8_t> out,
Span<const uint8_t> secret, std::string_view label,
Span<const uint8_t> seed1, Span<const uint8_t> seed2);
// Encryption layer.
// SSLAEADContext contains information about an AEAD that is being used to
// encrypt an SSL connection.
class SSLAEADContext {
public:
explicit SSLAEADContext(const SSL_CIPHER *cipher);
~SSLAEADContext();
static constexpr bool kAllowUniquePtr = true;
SSLAEADContext(const SSLAEADContext &&) = delete;
SSLAEADContext &operator=(const SSLAEADContext &&) = delete;
// CreateNullCipher creates an `SSLAEADContext` for the null cipher.
static UniquePtr<SSLAEADContext> CreateNullCipher();
// Create creates an `SSLAEADContext` using the supplied key material. It
// returns nullptr on error. Only one of `Open` or `Seal` may be used with the
// resulting object, depending on `direction`. `version` is the wire version.
static UniquePtr<SSLAEADContext> Create(enum evp_aead_direction_t direction,
uint16_t version,
const SSL_CIPHER *cipher,
Span<const uint8_t> enc_key,
Span<const uint8_t> mac_key,
Span<const uint8_t> fixed_iv);
// CreatePlaceholderForQUIC creates a placeholder `SSLAEADContext` for the
// given cipher. The resulting object can be queried for various properties
// but cannot encrypt or decrypt data.
static UniquePtr<SSLAEADContext> CreatePlaceholderForQUIC(
const SSL_CIPHER *cipher);
const SSL_CIPHER *cipher() const { return cipher_; }
// is_null_cipher returns true if this is the null cipher.
bool is_null_cipher() const { return !cipher_; }
// ExplicitNonceLen returns the length of the explicit nonce.
size_t ExplicitNonceLen() const;
// MaxOverhead returns the maximum overhead of calling `Seal`.
size_t MaxOverhead() const;
// MaxSealInputLen returns the maximum length for `Seal` that can fit in
// `max_out` output bytes, or zero if no input may fit.
size_t MaxSealInputLen(size_t max_out) const;
// SuffixLen calculates the suffix length written by `SealScatter` and writes
// it to `*out_suffix_len`. It returns true on success and false on error.
// `in_len` and `extra_in_len` should equal the argument of the same names
// passed to `SealScatter`.
bool SuffixLen(size_t *out_suffix_len, size_t in_len,
size_t extra_in_len) const;
// CiphertextLen calculates the total ciphertext length written by
// `SealScatter` and writes it to `*out_len`. It returns true on success and
// false on error. `in_len` and `extra_in_len` should equal the argument of
// the same names passed to `SealScatter`.
bool CiphertextLen(size_t *out_len, size_t in_len, size_t extra_in_len) const;
// Open authenticates and decrypts `in` in-place. On success, it sets `*out`
// to the plaintext in `in` and returns true. Otherwise, it returns
// false. The output will always be `ExplicitNonceLen` bytes ahead of `in`.
bool Open(Span<uint8_t> *out, uint8_t type, uint16_t record_version,
uint64_t seqnum, Span<const uint8_t> header, Span<uint8_t> in);
// Seal encrypts and authenticates `in_len` bytes from `in` and writes the
// result to `out`. It returns true on success and false on error.
//
// If `in` and `out` alias then `out` + `ExplicitNonceLen` must be == `in`.
bool Seal(uint8_t *out, size_t *out_len, size_t max_out, uint8_t type,
uint16_t record_version, uint64_t seqnum,
Span<const uint8_t> header, const uint8_t *in, size_t in_len);
// SealScatter encrypts and authenticates `in_len` bytes from `in` and splits
// the result between `out_prefix`, `out` and `out_suffix`. It returns one on
// success and zero on error.
//
// On successful return, exactly `ExplicitNonceLen` bytes are written to
// `out_prefix`, `in_len` bytes to `out`, and `SuffixLen` bytes to
// `out_suffix`.
//
// `extra_in` may point to an additional plaintext buffer. If present,
// `extra_in_len` additional bytes are encrypted and authenticated, and the
// ciphertext is written to the beginning of `out_suffix`. `SuffixLen` should
// be used to size `out_suffix` accordingly.
//
// If `in` and `out` alias then `out` must be == `in`. Other arguments may not
// alias anything.
bool SealScatter(uint8_t *out_prefix, uint8_t *out, uint8_t *out_suffix,
uint8_t type, uint16_t record_version, uint64_t seqnum,
Span<const uint8_t> header, const uint8_t *in, size_t in_len,
const uint8_t *extra_in, size_t extra_in_len);
bool GetIV(const uint8_t **out_iv, size_t *out_iv_len) const;
private:
// GetAdditionalData returns the additional data, writing into `storage` if
// necessary.
Span<const uint8_t> GetAdditionalData(uint8_t storage[13], uint8_t type,
uint16_t record_version,
uint64_t seqnum, size_t plaintext_len,
Span<const uint8_t> header);
const SSL_CIPHER *cipher_;
ScopedEVP_AEAD_CTX ctx_;
// fixed_nonce_ contains any bytes of the nonce that are fixed for all
// records.
InplaceVector<uint8_t, 12> fixed_nonce_;
uint8_t variable_nonce_len_ = 0;
// variable_nonce_included_in_record_ is true if the variable nonce
// for a record is included as a prefix before the ciphertext.
bool variable_nonce_included_in_record_ : 1;
// random_variable_nonce_ is true if the variable nonce is
// randomly generated, rather than derived from the sequence
// number.
bool random_variable_nonce_ : 1;
// xor_fixed_nonce_ is true if the fixed nonce should be XOR'd into the
// variable nonce rather than prepended.
bool xor_fixed_nonce_ : 1;
// omit_length_in_ad_ is true if the length should be omitted in the
// AEAD's ad parameter.
bool omit_length_in_ad_ : 1;
// ad_is_header_ is true if the AEAD's ad parameter is the record header.
bool ad_is_header_ : 1;
};
// DTLS replay bitmap.
// DTLSReplayBitmap maintains a sliding window of sequence numbers to detect
// replayed packets.
class DTLSReplayBitmap {
public:
// ShouldDiscard returns true if `seq_num` has been seen in
// `bitmap` or is stale. Otherwise it returns false.
bool ShouldDiscard(uint64_t seqnum) const;
// Record updates the bitmap to record receipt of sequence number
// `seq_num`. It slides the window forward if needed. It is an error to call
// this function on a stale sequence number.
void Record(uint64_t seqnum);
uint64_t max_seq_num() const { return max_seq_num_; }
private:
// map is a bitset of sequence numbers that have been seen. Bit i corresponds
// to `max_seq_num_ - i`.
std::bitset<256> map_;
// max_seq_num_ is the largest sequence number seen so far as a 64-bit
// integer, or zero if none have been seen.
uint64_t max_seq_num_ = 0;
};
// reconstruct_seqnum takes the low order bits of a record sequence number from
// the wire and reconstructs the full sequence number. It does so using the
// algorithm described in section 4.2.2 of RFC 9147, where `wire_seq` is the
// low bits of the sequence number as seen on the wire, `seq_mask` is a bitmask
// of 8 or 16 1 bits corresponding to the length of the sequence number on the
// wire, and `max_valid_seqnum` is the largest sequence number of a record
// successfully deprotected in this epoch. This function returns the sequence
// number that is numerically closest to one plus `max_valid_seqnum` that when
// bitwise and-ed with `seq_mask` equals `wire_seq`.
//
// `max_valid_seqnum` must be most 2^48-1, in which case the output will also be
// at most 2^48-1.
uint64_t reconstruct_seqnum(uint16_t wire_seq, uint64_t seq_mask,
uint64_t max_valid_seqnum);
// Record layer.
class DTLSRecordNumber {
public:
static constexpr uint64_t kMaxSequence = (uint64_t{1} << 48) - 1;
DTLSRecordNumber() = default;
DTLSRecordNumber(uint16_t epoch, uint64_t sequence) {
BSSL_CHECK(sequence <= kMaxSequence);
combined_ = (uint64_t{epoch} << 48) | sequence;
}
static DTLSRecordNumber FromCombined(uint64_t combined) {
return DTLSRecordNumber(combined);
}
bool operator==(DTLSRecordNumber r) const {
return combined() == r.combined();
}
bool operator!=(DTLSRecordNumber r) const { return !((*this) == r); }
bool operator<(DTLSRecordNumber r) const { return combined() < r.combined(); }
uint64_t combined() const { return combined_; }
uint16_t epoch() const { return combined_ >> 48; }
uint64_t sequence() const { return combined_ & kMaxSequence; }
bool HasNext() const { return sequence() < kMaxSequence; }
DTLSRecordNumber Next() const {
BSSL_CHECK(HasNext());
// This will not overflow into the epoch.
return DTLSRecordNumber::FromCombined(combined_ + 1);
}
private:
explicit DTLSRecordNumber(uint64_t combined) : combined_(combined) {}
uint64_t combined_ = 0;
};
class RecordNumberEncrypter {
public:
static constexpr bool kAllowUniquePtr = true;
static constexpr size_t kMaxKeySize = 32;
// Create returns a DTLS 1.3 record number encrypter for `traffic_secret`, or
// nullptr on error.
static UniquePtr<RecordNumberEncrypter> Create(
const SSL_CIPHER *cipher, Span<const uint8_t> traffic_secret);
virtual ~RecordNumberEncrypter() = default;
virtual size_t KeySize() = 0;
virtual bool SetKey(Span<const uint8_t> key) = 0;
virtual bool GenerateMask(Span<uint8_t> out, Span<const uint8_t> sample) = 0;
};
struct DTLSReadEpoch {
static constexpr bool kAllowUniquePtr = true;
// TODO(davidben): This could be made slightly more compact if `bitmap` stored
// a DTLSRecordNumber.
uint16_t epoch = 0;
UniquePtr<SSLAEADContext> aead;
UniquePtr<RecordNumberEncrypter> rn_encrypter;
DTLSReplayBitmap bitmap;
InplaceVector<uint8_t, SSL_MAX_MD_SIZE> traffic_secret;
};
struct DTLSWriteEpoch {
static constexpr bool kAllowUniquePtr = true;
uint16_t epoch() const { return next_record.epoch(); }
DTLSRecordNumber next_record;
UniquePtr<SSLAEADContext> aead;
UniquePtr<RecordNumberEncrypter> rn_encrypter;
InplaceVector<uint8_t, SSL_MAX_MD_SIZE> traffic_secret;
};
// ssl_record_prefix_len returns the length of the prefix before the ciphertext
// of a record for `ssl`.
//
// TODO(davidben): Expose this as part of public API once the high-level
// buffer-free APIs are available.
size_t ssl_record_prefix_len(const SSL *ssl);
enum ssl_open_record_t {
ssl_open_record_success,
ssl_open_record_discard,
ssl_open_record_partial,
ssl_open_record_close_notify,
ssl_open_record_error,
};
// tls_open_record decrypts a record from `in` in-place.
//
// If the input did not contain a complete record, it returns
// `ssl_open_record_partial`. It sets `*out_consumed` to the total number of
// bytes necessary. It is guaranteed that a successful call to `tls_open_record`
// will consume at least that many bytes.
//
// Otherwise, it sets `*out_consumed` to the number of bytes of input
// consumed. Note that input may be consumed on all return codes if a record was
// decrypted.
//
// On success, it returns `ssl_open_record_success`. It sets `*out_type` to the
// record type and `*out` to the record body in `in`. Note that `*out` may be
// empty.
//
// If a record was successfully processed but should be discarded, it returns
// `ssl_open_record_discard`.
//
// If a record was successfully processed but is a close_notify, it returns
// `ssl_open_record_close_notify`.
//
// On failure or fatal alert, it returns `ssl_open_record_error` and sets
// `*out_alert` to an alert to emit, or zero if no alert should be emitted.
enum ssl_open_record_t tls_open_record(SSL *ssl, uint8_t *out_type,
Span<uint8_t> *out, size_t *out_consumed,
uint8_t *out_alert, Span<uint8_t> in);
// dtls_open_record implements `tls_open_record` for DTLS. It only returns
// `ssl_open_record_partial` if `in` was empty and sets `*out_consumed` to
// zero. The caller should read one packet and try again. On success,
// `*out_number` is set to the record number of the record.
enum ssl_open_record_t dtls_open_record(SSL *ssl, uint8_t *out_type,
DTLSRecordNumber *out_number,
Span<uint8_t> *out,
size_t *out_consumed,
uint8_t *out_alert, Span<uint8_t> in);
// ssl_needs_record_splitting returns one if `ssl`'s current outgoing cipher
// state needs record-splitting and zero otherwise.
bool ssl_needs_record_splitting(const SSL *ssl);
// tls_seal_record seals a new record of type `type` and body `in` and writes it
// to `out`. At most `max_out` bytes will be written. It returns true on success
// and false on error. If enabled, `tls_seal_record` implements TLS 1.0 CBC
// 1/n-1 record splitting and may write two records concatenated.
//
// For a large record, the bulk of the ciphertext will begin
// `tls_seal_align_prefix_len` bytes into out. Aligning `out` appropriately may
// improve performance. It writes at most `in_len` + `SSL_max_seal_overhead`
// bytes to `out`.
//
// `in` and `out` may not alias.
bool tls_seal_record(SSL *ssl, uint8_t *out, size_t *out_len, size_t max_out,
uint8_t type, const uint8_t *in, size_t in_len);
// dtls_record_header_write_len returns the length of the record header that
// will be written at `epoch`.
size_t dtls_record_header_write_len(const SSL *ssl, uint16_t epoch);
// dtls_max_seal_overhead returns the maximum overhead, in bytes, of sealing a
// record.
size_t dtls_max_seal_overhead(const SSL *ssl, uint16_t epoch);
// dtls_seal_prefix_len returns the number of bytes of prefix to reserve in
// front of the plaintext when sealing a record in-place.
size_t dtls_seal_prefix_len(const SSL *ssl, uint16_t epoch);
// dtls_seal_max_input_len returns the maximum number of input bytes that can
// fit in a record of up to `max_out` bytes, or zero if none may fit.
size_t dtls_seal_max_input_len(const SSL *ssl, uint16_t epoch, size_t max_out);
// dtls_get_read_epoch and dtls_get_write_epoch return the epoch corresponding
// to `epoch` or nullptr if there is none.
DTLSReadEpoch *dtls_get_read_epoch(const SSL *ssl, uint16_t epoch);
DTLSWriteEpoch *dtls_get_write_epoch(const SSL *ssl, uint16_t epoch);
// dtls_seal_record implements `tls_seal_record` for DTLS. `epoch` selects which
// epoch's cipher state to use. Unlike `tls_seal_record`, `in` and `out` may
// alias but, if they do, `in` must be exactly `dtls_seal_prefix_len` bytes
// ahead of `out`. On success, `*out_number` is set to the record number of the
// record.
bool dtls_seal_record(SSL *ssl, DTLSRecordNumber *out_number, uint8_t *out,
size_t *out_len, size_t max_out, uint8_t type,
const uint8_t *in, size_t in_len, uint16_t epoch);
// ssl_process_alert processes `in` as an alert and updates `ssl`'s shutdown
// state. It returns one of `ssl_open_record_discard`, `ssl_open_record_error`,
// `ssl_open_record_close_notify`, or `ssl_open_record_fatal_alert` as
// appropriate.
enum ssl_open_record_t ssl_process_alert(SSL *ssl, uint8_t *out_alert,
Span<const uint8_t> in);
// Private key operations.
// ssl_private_key_* perform the corresponding operation on
// `SSL_PRIVATE_KEY_METHOD`. If there is a custom private key configured, they
// call the corresponding function or `complete` depending on whether there is a
// pending operation. Otherwise, they implement the operation with
// `EVP_PKEY`.
enum ssl_private_key_result_t ssl_private_key_sign(
SSL_HANDSHAKE *hs, uint8_t *out, size_t *out_len, size_t max_out,
uint16_t sigalg, Span<const uint8_t> in);
enum ssl_private_key_result_t ssl_private_key_decrypt(SSL_HANDSHAKE *hs,
uint8_t *out,
size_t *out_len,
size_t max_out,
Span<const uint8_t> in);
// ssl_parse_peer_subject_public_key_info decodes a SubjectPublicKeyInfo
// representing the peer TLS key. It returns a newly-allocated `EVP_PKEY` or
// nullptr on error.
UniquePtr<EVP_PKEY> ssl_parse_peer_subject_public_key_info(
Span<const uint8_t> spki);
// ssl_pkey_supports_algorithm returns whether `pkey` may be used to sign
// `sigalg`.
bool ssl_pkey_supports_algorithm(const SSL *ssl, EVP_PKEY *pkey,
uint16_t sigalg, bool is_verify);
// ssl_public_key_verify verifies that the `signature` is valid for the public
// key `pkey` and input `in`, using the signature algorithm `sigalg`.
bool ssl_public_key_verify(SSL *ssl, Span<const uint8_t> signature,
uint16_t sigalg, EVP_PKEY *pkey,
Span<const uint8_t> in);
// Key shares.
// SSLKeyShare abstracts over KEM-like constructions, for use with TLS 1.2 ECDHE
// cipher suites and the TLS 1.3 key_share extension.
//
// TODO(davidben): This class is named SSLKeyShare after the TLS 1.3 key_share
// extension, but it really implements a KEM abstraction. Additionally, we use
// the same type for Encap, which is a one-off, stateless operation, as Generate
// and Decap. Slightly tidier would be for Generate to return a new SSLKEMKey
// (or we introduce EVP_KEM and EVP_KEM_KEY), with a Decap method, and for Encap
// to be static function.
class SSLKeyShare {
public:
virtual ~SSLKeyShare() {}
static constexpr bool kAllowUniquePtr = true;
// Create returns a SSLKeyShare instance for use with group `group_id` or
// nullptr on error.
static UniquePtr<SSLKeyShare> Create(uint16_t group_id);
// GroupID returns the group ID.
virtual uint16_t GroupID() const = 0;
// Generate generates a keypair and writes the public key to `out_public_key`.
// It returns true on success and false on error.
virtual bool Generate(CBB *out_public_key) = 0;
// Encap generates an ephemeral, symmetric secret and encapsulates it with
// `peer_key`. On success, it returns true, writes the encapsulated secret to
// `out_ciphertext`, and sets `*out_secret` to the shared secret. On failure,
// it returns false and sets `*out_alert` to an alert to send to the peer.
virtual bool Encap(CBB *out_ciphertext, Array<uint8_t> *out_secret,
uint8_t *out_alert, Span<const uint8_t> peer_key) = 0;
// Decap decapsulates the symmetric secret in `ciphertext`. On success, it
// returns true and sets `*out_secret` to the shared secret. On failure, it
// returns false and sets `*out_alert` to an alert to send to the peer.
virtual bool Decap(Array<uint8_t> *out_secret, uint8_t *out_alert,
Span<const uint8_t> ciphertext) = 0;
// SerializePrivateKey writes the private key to `out`, returning true if
// successful and false otherwise. It should be called after `Generate`.
virtual bool SerializePrivateKey(CBB *out) { return false; }
// DeserializePrivateKey initializes the state of the key exchange from `in`,
// returning true if successful and false otherwise.
virtual bool DeserializePrivateKey(CBS *in) { return false; }
};
struct NamedGroup {
int nid;
uint16_t group_id;
const char name[32], alias[32];
};
// NamedGroups returns all supported groups.
Span<const NamedGroup> NamedGroups();
// kNumNamedGroups is the number of supported groups.
constexpr size_t kNumNamedGroups = 7u;
// DefaultSupportedGroupIds returns the list of IDs for the default groups that
// are supported when the caller hasn't explicitly configured supported groups.
Span<const uint16_t> DefaultSupportedGroupIds();
// ssl_nid_to_group_id looks up the group corresponding to `nid`. On success, it
// sets `*out_group_id` to the group ID and returns true. Otherwise, it returns
// false.
bool ssl_nid_to_group_id(uint16_t *out_group_id, int nid);
// ssl_name_to_group_id looks up the group corresponding to the `name` string of
// length `len`. On success, it sets `*out_group_id` to the group ID and returns
// true. Otherwise, it returns false.
bool ssl_name_to_group_id(uint16_t *out_group_id, const char *name, size_t len);
// ssl_group_id_to_nid returns the NID corresponding to `group_id` or
// `NID_undef` if unknown.
int ssl_group_id_to_nid(uint16_t group_id);
// Handshake messages.
struct SSLMessage {
bool is_v2_hello;
uint8_t type;
CBS body;
// raw is the entire serialized handshake message, including the TLS or DTLS
// message header.
CBS raw;
};
// SSL_MAX_HANDSHAKE_FLIGHT is the number of messages, including
// ChangeCipherSpec, in the longest handshake flight. Currently this is the
// client's second leg in a full handshake when client certificates, NPN, and
// Channel ID, are all enabled.
#define SSL_MAX_HANDSHAKE_FLIGHT 7
extern const uint8_t kHelloRetryRequest[SSL3_RANDOM_SIZE];
extern const uint8_t kTLS12DowngradeRandom[8];
extern const uint8_t kTLS13DowngradeRandom[8];
extern const uint8_t kJDK11DowngradeRandom[8];
// ssl_max_handshake_message_len returns the maximum number of bytes permitted
// in a handshake message for `ssl`.
size_t ssl_max_handshake_message_len(const SSL *ssl);
// tls_can_accept_handshake_data returns whether `ssl` is able to accept more
// data into handshake buffer.
bool tls_can_accept_handshake_data(const SSL *ssl, uint8_t *out_alert);
// tls_has_unprocessed_handshake_data returns whether there is buffered
// handshake data that has not been consumed by `get_message`.
bool tls_has_unprocessed_handshake_data(const SSL *ssl);
// tls_append_handshake_data appends `data` to the handshake buffer. It returns
// true on success and false on allocation failure.
bool tls_append_handshake_data(SSL *ssl, Span<const uint8_t> data);
// dtls_has_unprocessed_handshake_data behaves like
// `tls_has_unprocessed_handshake_data` for DTLS.
bool dtls_has_unprocessed_handshake_data(const SSL *ssl);
// tls_flush_pending_hs_data flushes any handshake plaintext data.
bool tls_flush_pending_hs_data(SSL *ssl);
// dtls_clear_outgoing_messages releases all buffered outgoing messages.
void dtls_clear_outgoing_messages(SSL *ssl);
// dtls_clear_unused_write_epochs releases any write epochs that are no longer
// needed.
void dtls_clear_unused_write_epochs(SSL *ssl);
// Callbacks.
// ssl_do_info_callback calls `ssl`'s info callback, if set.
void ssl_do_info_callback(const SSL *ssl, int type, int value);
// ssl_do_msg_callback calls `ssl`'s message callback, if set.
void ssl_do_msg_callback(const SSL *ssl, int is_write, int content_type,
Span<const uint8_t> in);
// Transport buffers.
class SSLBuffer {
public:
SSLBuffer() {}
~SSLBuffer() { Clear(); }
SSLBuffer(const SSLBuffer &) = delete;
SSLBuffer &operator=(const SSLBuffer &) = delete;
uint8_t *data() { return buf_ + offset_; }
size_t size() const { return size_; }
bool empty() const { return size_ == 0; }
size_t cap() const { return cap_; }
Span<uint8_t> span() { return Span(data(), size()); }
Span<uint8_t> remaining() { return Span(data() + size(), cap() - size()); }
// Clear releases the buffer.
void Clear();
// EnsureCap ensures the buffer has capacity at least `new_cap`, aligned such
// that data written after `header_len` is aligned to a
// `SSL3_ALIGN_PAYLOAD`-byte boundary. It returns true on success and false
// on error.
bool EnsureCap(size_t header_len, size_t new_cap);
// DidWrite extends the buffer by `len`. The caller must have filled in to
// this point.
void DidWrite(size_t len);
// Consume consumes `len` bytes from the front of the buffer. The memory
// consumed will remain valid until the next call to `DiscardConsumed` or
// `Clear`.
void Consume(size_t len);
// DiscardConsumed discards the consumed bytes from the buffer. If the buffer
// is now empty, it releases memory used by it.
void DiscardConsumed();
private:
// buf_ is the memory allocated for this buffer.
uint8_t *buf_ = nullptr;
// offset_ is the offset into `buf_` which the buffer contents start at.
uint16_t offset_ = 0;
// size_ is the size of the buffer contents from `buf_` + `offset_`.
uint16_t size_ = 0;
// cap_ is how much memory beyond `buf_` + `offset_` is available.
uint16_t cap_ = 0;
// inline_buf_ is a static buffer for short reads.
uint8_t inline_buf_[SSL3_RT_HEADER_LENGTH];
};
// ssl_read_buffer_extend_to extends the read buffer to the desired length. For
// TLS, it reads to the end of the buffer until the buffer is `len` bytes
// long. For DTLS, it reads a new packet and ignores `len`. It returns one on
// success, zero on EOF, and a negative number on error.
//
// It is an error to call `ssl_read_buffer_extend_to` in DTLS when the buffer is
// non-empty.
int ssl_read_buffer_extend_to(SSL *ssl, size_t len);
// ssl_handle_open_record handles the result of passing `ssl->s3->read_buffer`
// to a record-processing function. If `ret` is a success or if the caller
// should retry, it returns one and sets `*out_retry`. Otherwise, it returns <=
// 0.
int ssl_handle_open_record(SSL *ssl, bool *out_retry, ssl_open_record_t ret,
size_t consumed, uint8_t alert);
// ssl_write_buffer_flush flushes the write buffer to the transport. It returns
// one on success and <= 0 on error. For DTLS, whether or not the write
// succeeds, the write buffer will be cleared.
int ssl_write_buffer_flush(SSL *ssl);
// Certificate functions.
// ssl_parse_cert_chain parses a certificate list from `cbs` in the format used
// by a TLS Certificate message. On success, it advances `cbs` and returns
// true. Otherwise, it returns false and sets `*out_alert` to an alert to send
// to the peer.
//
// If the list is non-empty then `*out_chain` and `*out_pubkey` will be set to
// the certificate chain and the leaf certificate's public key
// respectively. Otherwise, both will be set to nullptr.
//
// If the list is non-empty and `out_leaf_sha256` is non-NULL, it writes the
// SHA-256 hash of the leaf to `out_leaf_sha256`.
bool ssl_parse_cert_chain(uint8_t *out_alert,
UniquePtr<STACK_OF(CRYPTO_BUFFER)> *out_chain,
UniquePtr<EVP_PKEY> *out_pubkey,
uint8_t *out_leaf_sha256, CBS *cbs,
CRYPTO_BUFFER_POOL *pool);
// ssl_parse_rpk_cert parses a RawPublicKey certificate from `cbs` in the format
// used by a TLS 1.2 Certificate message (RFC 7250). On success, it advances
// `cbs` and returns true, and sets `*out_raw_public_key` to the parsed key, and
// sets `*out_pubkey` to the same key by incrementing the reference count, and
// if `out_rpk_sha256` is non-NULL, it writes the SHA-256 hash of the RPK to
// `out_rpk_sha256`. Otherwise, it returns false and sets `*out_alert` to an
// alert to send to the peer.
bool ssl_parse_rpk_cert(uint8_t *out_alert,
UniquePtr<EVP_PKEY> *out_raw_public_key,
UniquePtr<EVP_PKEY> *out_pubkey,
uint8_t *out_rpk_sha256, CBS *cbs);
enum ssl_key_usage_t {
key_usage_digital_signature = 0,
key_usage_encipherment = 2,
};
// ssl_cert_check_key_usage parses the DER-encoded, X.509 certificate in `in`
// and returns true if doesn't specify a key usage or, if it does, if it
// includes `bit`. Otherwise it pushes to the error queue and returns false.
bool ssl_cert_check_key_usage(const CBS *in, enum ssl_key_usage_t bit);
// ssl_cert_extract_issuer parses the DER-encoded, X.509 certificate in `in`
// and extracts the issuer. On success it returns true and the DER encoded
// issuer is in `out_dn`, otherwise it returns false.
bool ssl_cert_extract_issuer(const CBS *in, CBS *out_dn);
// ssl_cert_matches_issuer parses the DER-encoded, X.509 certificate in `in`
// and returns true if its issuer is an exact match for the DER encoded
// distinguished name in `dn`
bool ssl_cert_matches_issuer(const CBS *in, const CBS *dn);
// ssl_cert_parse_pubkey extracts the public key from the DER-encoded, X.509
// certificate in `in`. It returns an allocated `EVP_PKEY` or else returns
// nullptr and pushes to the error queue.
UniquePtr<EVP_PKEY> ssl_cert_parse_pubkey(const CBS *in);
// SSL_parse_CA_list parses a CA list from `cbs` in the format used by a TLS
// CertificateRequest message and Certificate Authorities extension. On success,
// it returns a newly-allocated `CRYPTO_BUFFER` list and advances
// `cbs`. Otherwise, it returns nullptr and sets `*out_alert` to an alert to
// send to the peer.
UniquePtr<STACK_OF(CRYPTO_BUFFER)> SSL_parse_CA_list(SSL *ssl,
uint8_t *out_alert,
CBS *cbs);
// ssl_has_client_CAs returns whether there are configured CAs.
bool ssl_has_client_CAs(const SSL_CONFIG *cfg);
// ssl_add_client_CA_list adds the configured CA list to `cbb` in the format
// used by a TLS CertificateRequest message. It returns true on success and
// false on error.
bool ssl_add_client_CA_list(const SSL_HANDSHAKE *hs, CBB *cbb);
// ssl_has_CA_names returns whether there are configured CA names.
bool ssl_has_CA_names(const SSL_CONFIG *cfg);
// ssl_add_CA_names adds the configured CA_names list to `cbb` in the format
// used by a TLS Certificate Authorities extension. It returns true on success
// and false on error.
bool ssl_add_CA_names(const SSL_HANDSHAKE *hs, CBB *cbb);
// ssl_check_leaf_certificate returns one if `pkey` and `leaf` are suitable as
// a server's leaf certificate for `hs`. Otherwise, it returns zero and pushes
// an error on the error queue.
bool ssl_check_leaf_certificate(SSL_HANDSHAKE *hs, EVP_PKEY *pkey,
const CRYPTO_BUFFER *leaf);
// TLS 1.3 key derivation.
// tls13_init_key_schedule initializes the handshake hash and key derivation
// state, and incorporates the PSK. The cipher suite and PRF hash must have been
// selected at this point. It returns true on success and false on error.
bool tls13_init_key_schedule(SSL_HANDSHAKE *hs, Span<const uint8_t> psk);
// tls13_init_early_key_schedule initializes the handshake hash and key
// derivation state from `session` for use with 0-RTT. It returns one on success
// and zero on error.
bool tls13_init_early_key_schedule(SSL_HANDSHAKE *hs,
const SSL_SESSION *session);
// tls13_advance_key_schedule incorporates `in` into the key schedule with
// HKDF-Extract. It returns true on success and false on error.
bool tls13_advance_key_schedule(SSL_HANDSHAKE *hs, Span<const uint8_t> in);
// tls13_set_traffic_key sets the read or write traffic keys to
// `traffic_secret`. The version and cipher suite are determined from `session`.
// It returns true on success and false on error.
bool tls13_set_traffic_key(SSL *ssl, enum ssl_encryption_level_t level,
enum evp_aead_direction_t direction,
const SSL_SESSION *session,
Span<const uint8_t> traffic_secret);
// tls13_derive_early_secret derives the early traffic secret. It returns true
// on success and false on error.
bool tls13_derive_early_secret(SSL_HANDSHAKE *hs);
// tls13_derive_handshake_secrets derives the handshake traffic secret. It
// returns true on success and false on error.
bool tls13_derive_handshake_secrets(SSL_HANDSHAKE *hs);
// tls13_rotate_traffic_key derives the next read or write traffic secret. It
// returns true on success and false on error.
bool tls13_rotate_traffic_key(SSL *ssl, enum evp_aead_direction_t direction);
// tls13_derive_application_secrets derives the initial application data traffic
// and exporter secrets based on the handshake transcripts and `master_secret`.
// It returns true on success and false on error.
bool tls13_derive_application_secrets(SSL_HANDSHAKE *hs);
// tls13_derive_resumption_secret derives the `resumption_secret`.
bool tls13_derive_resumption_secret(SSL_HANDSHAKE *hs);
// tls13_export_keying_material provides an exporter interface to use the
// `exporter_secret`.
bool tls13_export_keying_material(const SSL *ssl, Span<uint8_t> out,
Span<const uint8_t> secret,
std::string_view label,
Span<const uint8_t> context);
// tls13_finished_mac calculates the MAC of the handshake transcript to verify
// the integrity of the Finished message, and stores the result in `out` and
// length in `out_len`. `is_server` is true if this is for the Server Finished
// and false for the Client Finished.
bool tls13_finished_mac(SSL_HANDSHAKE *hs, uint8_t *out, size_t *out_len,
bool is_server);
// tls13_derive_session_psk calculates the PSK for this session based on the
// resumption master secret and `nonce`. It returns true on success, and false
// on failure.
bool tls13_derive_session_psk(SSL_SESSION *session, Span<const uint8_t> nonce,
bool is_dtls);
struct SSLImportedPSK {
static constexpr bool kAllowUniquePtr = true;
UniquePtr<SSLCredential> credential;
Array<uint8_t> imported_identity;
InplaceVector<uint8_t, SSL_MAX_MD_SIZE> ipskx;
uint16_t protocol = 0;
const EVP_MD *md = nullptr;
};
// tls13_derive_imported_psk computes the imported PSK value for `cred`, which
// must be an PSK credential, for use with a target KDF of HKDF with `hkdf_md`.
// `protocol` should be the wire version (i.e. `TLS1_3_VERSION` or
// `DTLS1_3_VERSION`) of the target protocol. It returns the imported PSK on
// success and std::nullopt on error.
std::optional<SSLImportedPSK> tls13_derive_imported_psk(const SSL_HANDSHAKE *hs,
SSLCredential *cred,
uint16_t protocol,
const EVP_MD *hkdf_md);
// tls13_compare_imported_psk_identity returns whether `id` is equal to `cred`'s
// imported identity for the specified target protocol and target KDF. This
// allows matching against PSK identities without deriving imported PSK keys.
bool tls13_compare_imported_psk_identity(Span<const uint8_t> id,
const SSLCredential *cred,
uint16_t protocol,
const EVP_MD *hkdf_md);
using SSLPreSharedKey = std::variant<SSLImportedPSK, UniquePtr<SSL_SESSION>>;
BORINGSSL_MAKE_DELETER(SSLPreSharedKey, Delete)
// ssl_pre_shared_key_hash return's `psk`'s hash.
const EVP_MD *ssl_pre_shared_key_hash(const SSLPreSharedKey &psk);
// ssl_pre_shared_key_identity return's `psk`'s identity.
Span<const uint8_t> ssl_pre_shared_key_identity(const SSLPreSharedKey &psk);
// ssl_pre_shared_key_secret return's `psk`'s secret.
Span<const uint8_t> ssl_pre_shared_key_secret(const SSLPreSharedKey &psk);
// tls13_psk_binder calculates the PSK binder value for `psk` over `transcript`
// and `client_hello`. On success, it writes the result to `out`, sets
// `*out_len` to the length, and returns true. Otherwise, it returns false.
// `binders_len` must be the length of the binders field, covering all binders
// and the overall length prefix, in `client_hello`.
bool tls13_psk_binder(const SSL_HANDSHAKE *hs, Span<uint8_t> out,
size_t *out_len, const SSLPreSharedKey &psk,
const SSLTranscript &transcript,
Span<const uint8_t> client_hello, size_t binders_len);
// Encrypted ClientHello.
struct ECHConfig {
static constexpr bool kAllowUniquePtr = true;
// raw contains the serialized ECHConfig.
Array<uint8_t> raw;
// The following fields alias into `raw`.
Span<const uint8_t> public_key;
Span<const uint8_t> public_name;
Span<const uint8_t> cipher_suites;
uint16_t kem_id = 0;
uint8_t maximum_name_length = 0;
uint8_t config_id = 0;
};
class ECHServerConfig {
public:
static constexpr bool kAllowUniquePtr = true;
ECHServerConfig() = default;
ECHServerConfig(const ECHServerConfig &other) = delete;
ECHServerConfig &operator=(ECHServerConfig &&) = delete;
// Init parses `ech_config` as an ECHConfig and saves a copy of `key`.
// It returns true on success and false on error.
bool Init(Span<const uint8_t> ech_config, const EVP_HPKE_KEY *key,
bool is_retry_config);
// SetupContext sets up `ctx` for a new connection, given the specified
// HPKE ciphersuite and encapsulated KEM key. It returns true on success and
// false on error. This function may only be called on an initialized object.
bool SetupContext(EVP_HPKE_CTX *ctx, uint16_t kdf_id, uint16_t aead_id,
Span<const uint8_t> enc) const;
const ECHConfig &ech_config() const { return ech_config_; }
bool is_retry_config() const { return is_retry_config_; }
private:
ECHConfig ech_config_;
ScopedEVP_HPKE_KEY key_;
bool is_retry_config_ = false;
};
class SSLECHKeys : public ssl_ech_keys_st, public bssl::RefCounted<SSLECHKeys> {
public:
SSLECHKeys() : RefCounted(CheckSubClass()) {}
Vector<UniquePtr<ECHServerConfig>> configs;
private:
friend RefCounted;
~SSLECHKeys() = default;
};
enum ssl_client_hello_type_t {
ssl_client_hello_unencrypted,
ssl_client_hello_inner,
ssl_client_hello_outer,
};
// ECH_CLIENT_* are types for the ClientHello encrypted_client_hello extension.
#define ECH_CLIENT_OUTER 0
#define ECH_CLIENT_INNER 1
// ssl_decode_client_hello_inner recovers the full ClientHelloInner from the
// EncodedClientHelloInner `encoded_client_hello_inner` by replacing its
// outer_extensions extension with the referenced extensions from the
// ClientHelloOuter `client_hello_outer`. If successful, it writes the recovered
// ClientHelloInner to `out_client_hello_inner`. It returns true on success and
// false on failure.
//
// This function is exported for fuzzing.
OPENSSL_EXPORT bool ssl_decode_client_hello_inner(
SSL *ssl, uint8_t *out_alert, Array<uint8_t> *out_client_hello_inner,
Span<const uint8_t> encoded_client_hello_inner,
const SSL_CLIENT_HELLO *client_hello_outer);
// ssl_client_hello_decrypt attempts to decrypt and decode the `payload`. It
// writes the result to `*out`. `payload` must point into `client_hello_outer`.
// It returns true on success and false on error. On error, it sets
// `*out_is_decrypt_error` to whether the failure was due to a bad ciphertext.
bool ssl_client_hello_decrypt(SSL_HANDSHAKE *hs, uint8_t *out_alert,
bool *out_is_decrypt_error, Array<uint8_t> *out,
const SSL_CLIENT_HELLO *client_hello_outer,
Span<const uint8_t> payload);
#define ECH_CONFIRMATION_SIGNAL_LEN 8
// ssl_ech_confirmation_signal_hello_offset returns the offset of the ECH
// confirmation signal in a ServerHello message, including the handshake header.
size_t ssl_ech_confirmation_signal_hello_offset(const SSL *ssl);
// ssl_ech_accept_confirmation computes the server's ECH acceptance signal,
// writing it to `out`. The transcript portion is the concatenation of
// `transcript` with `msg`. The `ECH_CONFIRMATION_SIGNAL_LEN` bytes from
// `offset` in `msg` are replaced with zeros before hashing. This function
// returns true on success, and false on failure.
bool ssl_ech_accept_confirmation(
const SSL_HANDSHAKE *hs, Span<uint8_t, ECH_CONFIRMATION_SIGNAL_LEN> out,
Span<const uint8_t, SSL3_RANDOM_SIZE> client_random,
const SSLTranscript &transcript, bool is_hrr, Span<const uint8_t> msg,
size_t offset);
// ssl_is_valid_ech_public_name returns true if `public_name` is a valid ECH
// public name and false otherwise. It is exported for testing.
bool ssl_is_valid_ech_public_name(Span<const uint8_t> public_name);
// ssl_is_valid_ech_config_list returns true if `ech_config_list` is a valid
// ECHConfigList structure and false otherwise.
bool ssl_is_valid_ech_config_list(Span<const uint8_t> ech_config_list);
// ssl_select_ech_config selects an ECHConfig and associated parameters to offer
// on the client and updates `hs`. It returns true on success, whether an
// ECHConfig was found or not, and false on internal error. On success, the
// encapsulated key is written to `out_enc` and `*out_enc_len` is set to the
// number of bytes written. If the function did not select an ECHConfig, the
// encapsulated key is the empty string.
bool ssl_select_ech_config(SSL_HANDSHAKE *hs, Span<uint8_t> out_enc,
size_t *out_enc_len);
// ssl_ech_extension_body_length returns the length of the body of a ClientHello
// ECH extension that encrypts `in_len` bytes with `aead` and an 'enc' value of
// length `enc_len`. The result does not include the four-byte extension header.
size_t ssl_ech_extension_body_length(const EVP_HPKE_AEAD *aead, size_t enc_len,
size_t in_len);
// ssl_encrypt_client_hello constructs a new ClientHelloInner, adds it to the
// inner transcript, and encrypts for inclusion in the ClientHelloOuter. `enc`
// is the encapsulated key to include in the extension. It returns true on
// success and false on error. If not offering ECH, `enc` is ignored and the
// function will compute a GREASE ECH extension if necessary, and otherwise
// return success while doing nothing.
//
// Encrypting the ClientHelloInner incorporates all extensions in the
// ClientHelloOuter, so all other state necessary for `ssl_add_client_hello`
// must already be computed.
bool ssl_encrypt_client_hello(SSL_HANDSHAKE *hs, Span<const uint8_t> enc);
// Credentials.
enum class SSLCredentialType {
kX509,
kDelegated,
kSPAKE2PlusV1Client,
kSPAKE2PlusV1Server,
kPreSharedKey,
kRawPublicKey,
};
class SSLCredential : public ssl_credential_st,
public RefCounted<SSLCredential> {
public:
explicit SSLCredential(SSLCredentialType type);
SSLCredential(const SSLCredential &) = delete;
SSLCredential &operator=(const SSLCredential &) = delete;
// Dup returns a copy of the credential, or nullptr on error. The `ex_data`
// values are not copied. This is only used on the legacy credential, whose
// `ex_data` is inaccessible.
UniquePtr<SSLCredential> Dup() const;
// ClearCertAndKey erases any certificate and private key on the credential.
void ClearCertAndKey();
// UsesX509 returns true if the credential type uses an X.509 certificate.
bool UsesX509() const;
// UsesPrivateKey returns true if the credential type uses an asymmetric
// private and public keypair.
bool UsesPrivateKey() const;
// IsComplete returns whether all required fields in the credential have been
// filled in.
bool IsComplete() const;
// SetLeafCert sets the leaf certificate to `leaf`, leaving the remaining
// certificates unmodified. It returns true on success and false on error. If
// `discard_key_on_mismatch` is true and the private key is inconsistent with
// the new leaf certificate, it is silently discarded.
bool SetLeafCert(UniquePtr<CRYPTO_BUFFER> leaf, bool discard_key_on_mismatch);
// ClearIntermediateCerts clears intermediate certificates in the certificate
// chain, while preserving the leaf.
void ClearIntermediateCerts();
// AppendIntermediateCert appends `cert` to the certificate chain. If there is
// no leaf certificate configured, it leaves a placeholder null in `chain`. It
// returns one on success and zero on error.
bool AppendIntermediateCert(UniquePtr<CRYPTO_BUFFER> cert);
// ChainContainsIssuer returns true if `dn` is a byte for byte match with the
// issuer of any certificate in `chain`, false otherwise.
bool ChainContainsIssuer(Span<const uint8_t> dn) const;
// type is the credential type and determines which other fields apply.
SSLCredentialType type;
// pubkey is the cached public key of the credential. Unlike `privkey`, it is
// always present and is extracted from the certificate, delegated credential,
// etc.
UniquePtr<EVP_PKEY> pubkey;
// privkey is the private key of the credential. It may be omitted in favor of
// `key_method`.
UniquePtr<EVP_PKEY> privkey;
// key_method, if non-null, is a set of callbacks to call for private key
// operations.
const SSL_PRIVATE_KEY_METHOD *key_method = nullptr;
// sigalgs, if non-empty, is the set of signature algorithms supported by the
// private key in decreasing order of preference. If empty, the default list
// is used.
//
// In delegated credentials, this field is not configurable and is instead
// computed from the dc_cert_verify_algorithm field.
Array<uint16_t> sigalgs;
// chain contains the certificate chain, with the leaf at the beginning. The
// first element of `chain` may be nullptr to indicate that the leaf
// certificate has not yet been set.
// If `chain` != nullptr -> len(chain) >= 1
// If `chain[0]` == nullptr -> len(chain) >= 2.
// `chain[1..]` != nullptr
UniquePtr<STACK_OF(CRYPTO_BUFFER)> chain;
// dc is the DelegatedCredential structure, if this is a delegated credential.
UniquePtr<CRYPTO_BUFFER> dc;
// dc_algorithm is the signature scheme of the signature over the delegated
// credential itself, made by the end-entity certificate's public key.
uint16_t dc_algorithm = 0;
// Signed certificate timestamp list to be sent to the client, if requested
UniquePtr<CRYPTO_BUFFER> signed_cert_timestamp_list;
// OCSP response to be sent to the client, if requested.
UniquePtr<CRYPTO_BUFFER> ocsp_response;
// SPAKE2+-specific information.
Array<uint8_t> pake_context;
Array<uint8_t> client_identity;
Array<uint8_t> server_identity;
Array<uint8_t> password_verifier_w0;
Array<uint8_t> password_verifier_w1; // server-only
Array<uint8_t> registration_record; // client-only
mutable std::atomic<uint32_t> pake_limit;
// External-PSK-specific information. epskx is the HKDF-Extract-ed value, from
// Section 5.1 of RFC 9258.
Array<uint8_t> epskx;
Array<uint8_t> epsk_id;
const EVP_MD *epsk_md = nullptr;
Array<uint8_t> epsk_context;
// Checks whether there are still permitted PAKE attempts remaining, without
// changing the counter.
bool HasPAKEAttempts() const;
// Atomically decrement `pake_limit`. Return true if successful and false if
// `pake_limit` is already zero.
bool ClaimPAKEAttempt() const;
// Atomically increment `pake_limit`. This must be paired with a
// `ClaimPAKEAttempt` call.
void RestorePAKEAttempt() const;
// trust_anchor_id, if non-empty, is the trust anchor ID for the root of the
// chain in `chain`.
Array<uint8_t> trust_anchor_id;
CRYPTO_EX_DATA ex_data;
// must_match_issuer is a flag indicating that this credential should be
// considered only when it matches a peer request for a particular issuer via
// a negotiation mechanism (such as the certificate_authorities extension).
// This also implies that chain is a certificate path ending in a certificate
// issued by the certificate with that trust anchor identifier.
bool must_match_issuer = false;
private:
friend RefCounted;
~SSLCredential();
};
// ssl_get_full_credential_list computes `hs`'s full credential list, including
// the legacy credential. On success, it writes it to `*out` and returns true.
// Otherwise, it returns false. The credential list may be empty, in which case
// this function will successfully output an empty array.
//
// This function should be called at most once during the handshake and is
// intended to be used for certificate-based credentials. It runs the
// auto-chaining logic as part of finishing the legacy credential. Other uses of
// the credential list (e.g. PAKE credentials) should iterate over
// `hs->config->cert->credentials`.
//
// The pointers in the result are only valid until `hs` is next mutated.
bool ssl_get_full_credential_list(SSL_HANDSHAKE *hs,
Array<SSLCredential *> *out);
// ssl_credential_matches_requested_issuers returns true if `cred` is a
// usable match for any requested issuers in `hs`, and false with an error
// otherwise.
bool ssl_credential_matches_requested_issuers(SSL_HANDSHAKE *hs,
const SSLCredential *cred);
// ssl_check_tls13_credential_ignoring_issuer returns true if `cred` is usable
// as the certificate in a TLS 1.3 handshake, ignoring the issuer check.
// `allowed_cert_types` is a nonempty set of cert types (`TLSEXT_cert_type_*`
// values) that are usable; `cred` must match one of these types.
// `out_sigalg` will be set to a matching signature algorithm if true is
// returned.
bool ssl_check_tls13_credential_ignoring_issuer(
SSL_HANDSHAKE *hs, Span<const uint8_t> allowed_cert_types,
const SSLCredential *cred, uint16_t *out_sigalg);
// Client certificate type & Server certificate type.
inline constexpr uint8_t kAllCertTypes[] = {
TLSEXT_cert_type_x509,
TLSEXT_cert_type_rpk,
};
inline constexpr size_t kNumCertTypes = std::size(kAllCertTypes);
inline constexpr uint8_t kDefaultCertType = TLSEXT_cert_type_x509;
// ssl_credential_type_to_cert_type returns the certificate type value
// (`TLSEXT_cert_type_*` value) corresponding to `cred_type`, or else
// std::nullopt.
std::optional<uint8_t> ssl_credential_type_to_cert_type(
SSLCredentialType cred_type);
// ssl_setup_client_certificate_type computes the client cert types to offer, as
// a client, and saves them in `hs`. The values are used later when checking
// that the server responded with a valid value.
void ssl_setup_client_certificate_type(SSL_HANDSHAKE *hs);
// ssl_negotiate_client_certificate_type, for a server, negotiates the
// client_certificate_type extension, if applicable. It updates
// `hs->peer_cert_type` appropriately and returns true if negotiation was
// successful or not necessary (i.e. if we are not requesting a cert from the
// client), or it returns false and sets `*out_alert` to an alert on error.
bool ssl_negotiate_client_certificate_type(
SSL_HANDSHAKE *hs, uint8_t *out_alert,
const SSL_CLIENT_HELLO *client_hello);
// ssl_get_allowed_server_cert_types, for a server, returns the cert types that
// may be used based on the server_certificate_type extension in the
// ClientHello. It returns a nonempty list of allowable certificate types. By
// default, if the client did not send the extension, X.509 certificates are
// allowed. The returned cert types may include unrecognized values. Returns
// nullopt and sets `out_alert` on failure.
std::optional<Span<const uint8_t>> ssl_get_allowed_server_cert_types(
const SSL_HANDSHAKE *hs, const SSL_CLIENT_HELLO *client_hello,
uint8_t *out_alert);
// Handshake functions.
enum ssl_hs_wait_t {
ssl_hs_error,
ssl_hs_ok,
ssl_hs_read_server_hello,
ssl_hs_read_message,
ssl_hs_flush,
ssl_hs_certificate_selection_pending,
ssl_hs_handoff,
ssl_hs_handback,
ssl_hs_x509_lookup,
ssl_hs_private_key_operation,
ssl_hs_pending_session,
ssl_hs_pending_ticket,
ssl_hs_early_return,
ssl_hs_early_data_rejected,
ssl_hs_read_end_of_early_data,
ssl_hs_read_change_cipher_spec,
ssl_hs_certificate_verify,
ssl_hs_hints_ready,
};
enum ssl_grease_index_t {
ssl_grease_cipher = 0,
ssl_grease_group,
ssl_grease_extension1,
ssl_grease_extension2,
ssl_grease_version,
ssl_grease_ticket_extension,
ssl_grease_ech_config_id,
ssl_grease_last_index = ssl_grease_ech_config_id,
};
enum tls12_server_hs_state_t {
state12_start_accept = 0,
state12_read_client_hello,
state12_read_client_hello_after_ech,
state12_cert_callback,
state12_tls13,
state12_select_parameters,
state12_send_server_hello,
state12_send_server_certificate,
state12_send_server_key_exchange,
state12_send_server_hello_done,
state12_read_client_certificate,
state12_verify_client_certificate,
state12_read_client_key_exchange,
state12_read_client_certificate_verify,
state12_read_change_cipher_spec,
state12_process_change_cipher_spec,
state12_read_next_proto,
state12_read_channel_id,
state12_read_client_finished,
state12_send_server_finished,
state12_finish_server_handshake,
state12_done,
};
enum tls13_server_hs_state_t {
state13_select_parameters = 0,
state13_select_session,
state13_send_hello_retry_request,
state13_read_second_client_hello,
state13_send_server_hello,
state13_send_server_certificate_verify,
state13_send_server_finished,
state13_send_half_rtt_ticket,
state13_read_second_client_flight,
state13_process_end_of_early_data,
state13_read_client_encrypted_extensions,
state13_read_client_certificate,
state13_read_client_certificate_verify,
state13_read_channel_id,
state13_read_client_finished,
state13_send_new_session_ticket,
state13_done,
};
// handback_t lists the points in the state machine where a handback can occur.
// These are the different points at which key material is no longer needed.
enum handback_t {
handback_after_session_resumption = 0,
handback_after_ecdhe = 1,
handback_after_handshake = 2,
handback_tls13 = 3,
handback_max_value = handback_tls13,
};
// SSL_HANDSHAKE_HINTS contains handshake hints for a connection. See
// `SSL_request_handshake_hints` and related functions.
struct SSL_HANDSHAKE_HINTS {
static constexpr bool kAllowUniquePtr = true;
Array<uint8_t> server_random_tls12;
Array<uint8_t> server_random_tls13;
uint16_t key_share_group_id = 0;
Array<uint8_t> key_share_ciphertext;
Array<uint8_t> key_share_secret;
uint16_t signature_algorithm = 0;
Array<uint8_t> signature_input;
Array<uint8_t> signature_spki;
Array<uint8_t> signature;
Array<uint8_t> decrypted_psk;
bool ignore_psk = false;
uint16_t cert_compression_alg_id = 0;
Array<uint8_t> cert_compression_input;
Array<uint8_t> cert_compression_output;
uint16_t ecdhe_group_id = 0;
Array<uint8_t> ecdhe_public_key;
Array<uint8_t> ecdhe_private_key;
Array<uint8_t> decrypted_ticket;
bool renew_ticket = false;
bool ignore_ticket = false;
};
struct SSLPAKEShare {
static constexpr bool kAllowUniquePtr = true;
uint16_t named_pake;
Array<uint8_t> client_identity;
Array<uint8_t> server_identity;
Array<uint8_t> pake_message;
};
struct SSL_HANDSHAKE {
explicit SSL_HANDSHAKE(SSL *ssl);
~SSL_HANDSHAKE();
static constexpr bool kAllowUniquePtr = true;
// ssl is a non-owning pointer to the parent `SSL` object.
SSL *ssl;
// config is a non-owning pointer to the handshake configuration.
SSL_CONFIG *config;
// wait contains the operation the handshake is currently blocking on or
// `ssl_hs_ok` if none.
enum ssl_hs_wait_t wait = ssl_hs_ok;
// state is the internal state for the TLS 1.2 and below handshake. Its
// values depend on `do_handshake` but the starting state is always zero.
int state = 0;
// tls13_state is the internal state for the TLS 1.3 handshake. Its values
// depend on `do_handshake` but the starting state is always zero.
int tls13_state = 0;
// min_version is the minimum accepted protocol version, taking account both
// `SSL_OP_NO_*` and `SSL_CTX_set_min_proto_version` APIs.
uint16_t min_version = 0;
// max_version is the maximum accepted protocol version, taking account both
// `SSL_OP_NO_*` and `SSL_CTX_set_max_proto_version` APIs.
uint16_t max_version = 0;
InplaceVector<uint8_t, SSL_MAX_MD_SIZE> secret;
InplaceVector<uint8_t, SSL_MAX_MD_SIZE> early_traffic_secret;
InplaceVector<uint8_t, SSL_MAX_MD_SIZE> client_handshake_secret;
InplaceVector<uint8_t, SSL_MAX_MD_SIZE> server_handshake_secret;
InplaceVector<uint8_t, SSL_MAX_MD_SIZE> client_traffic_secret_0;
InplaceVector<uint8_t, SSL_MAX_MD_SIZE> server_traffic_secret_0;
InplaceVector<uint8_t, SSL_MAX_MD_SIZE> expected_client_finished;
// GetClientHello, on the server, returns either the normal ClientHello
// message or the ClientHelloInner if it has been serialized to
// `ech_client_hello_buf`. This function should only be called when the
// current message is a ClientHello. It returns true on success and false on
// error.
//
// Note that fields of the returned `out_msg` and `out_client_hello` point
// into a handshake-owned buffer, so their lifetimes should not exceed this
// SSL_HANDSHAKE.
bool GetClientHello(SSLMessage *out_msg, SSL_CLIENT_HELLO *out_client_hello);
union {
// sent is a bitset where the bits correspond to elements of kExtensions
// in extensions.cc. Each bit is set if that extension was sent in a
// ClientHello. It's not used by servers.
uint32_t sent = 0;
// received is a bitset, like `sent`, but is used by servers to record
// which extensions were received from a client.
uint32_t received;
} extensions;
// inner_extensions_sent, on clients that offer ECH, is `extensions.sent` for
// the ClientHelloInner.
uint32_t inner_extensions_sent = 0;
// early_data_written is the amount of early data that has been written by the
// record layer.
uint32_t early_data_written = 0;
// error, if `wait` is `ssl_hs_error`, is the error the handshake failed on.
UniquePtr<ERR_SAVE_STATE> error;
// key_shares are the current key exchange instances, in preference order. Any
// members of this vector must be non-null.
InplaceVector<UniquePtr<SSLKeyShare>, kNumNamedGroups> key_shares;
// pre_shared_keys are the pre-shared keys to be offered by the client.
Vector<SSLPreSharedKey> pre_shared_keys;
// pre_shared_key is the selected pre-shared key on the server.
UniquePtr<SSLPreSharedKey> pre_shared_key;
// selected_psk_index is the index of the selected pre-shared key on the
// server.
std::optional<uint16_t> selected_psk_index;
// transcript is the current handshake transcript.
SSLTranscript transcript;
// inner_transcript, on the client, is the handshake transcript for the
// ClientHelloInner handshake. It is moved to `transcript` if the server
// accepts ECH.
SSLTranscript inner_transcript;
// inner_client_random is the ClientHello random value used with
// ClientHelloInner.
uint8_t inner_client_random[SSL3_RANDOM_SIZE] = {0};
// cookie is the value of the cookie in HelloRetryRequest, or empty if none
// was received.
Array<uint8_t> cookie;
// dtls_cookie is the value of the cookie in DTLS HelloVerifyRequest. If
// empty, either none was received or HelloVerifyRequest contained an empty
// cookie. Check the received_hello_verify_request field to distinguish an
// empty cookie from no HelloVerifyRequest message being received.
Array<uint8_t> dtls_cookie;
// ech_client_outer contains the outer ECH extension to send in the
// ClientHello, excluding the header and type byte.
Array<uint8_t> ech_client_outer;
// ech_retry_configs, on the client, contains the retry configs from the
// server as a serialized ECHConfigList.
Array<uint8_t> ech_retry_configs;
// ech_client_hello_buf, on the server, contains the bytes of the
// reconstructed ClientHelloInner message.
Array<uint8_t> ech_client_hello_buf;
// key_share_bytes is the key_share extension that the client should send.
Array<uint8_t> key_share_bytes;
// key_share_ciphertext, for servers, is encapsulated shared secret to be sent
// to the client in the TLS 1.3 key_share extension.
Array<uint8_t> key_share_ciphertext;
// peer_sigalgs are the signature algorithms that the peer supports. These are
// taken from the contents of the signature algorithms extension for a server
// or from the CertificateRequest for a client.
Array<uint16_t> peer_sigalgs;
// peer_supported_group_list contains the supported group IDs advertised by
// the peer. This is only set on the server's end. The server does not
// advertise this extension to the client.
Array<uint16_t> peer_supported_group_list;
// peer_delegated_credential_sigalgs are the signature algorithms the peer
// supports with delegated credentials, or empty if the peer does not support
// delegated credentials.
Array<uint16_t> peer_delegated_credential_sigalgs;
// peer_key is the peer's ECDH key for a TLS 1.2 client.
Array<uint8_t> peer_key;
// extension_permutation is the permutation to apply to ClientHello
// extensions. It maps indices into the `kExtensions` table into other
// indices.
Array<uint8_t> extension_permutation;
// cert_compression_alg_id, for a server, contains the negotiated certificate
// compression algorithm for this client. It is only valid if
// `cert_compression_negotiated` is true.
uint16_t cert_compression_alg_id;
// ech_hpke_ctx is the HPKE context used in ECH. On the server, it is
// initialized if `ech_status` is `ssl_ech_accepted`. On the client, it is
// initialized if `selected_ech_config` is not nullptr.
ScopedEVP_HPKE_CTX ech_hpke_ctx;
// server_params, in a TLS 1.2 server, stores the ServerKeyExchange
// parameters. It has client and server randoms prepended for signing
// convenience.
Array<uint8_t> server_params;
// peer_psk_identity_hint, on the client, is the psk_identity_hint sent by the
// server when using a TLS 1.2 PSK key exchange.
UniquePtr<char> peer_psk_identity_hint;
// ca_names contains the list of CAs received via the Certificate Authorities
// extension in our peer's CertificateRequest or ClientHello message
UniquePtr<STACK_OF(CRYPTO_BUFFER)> ca_names;
// peer_requested_trust_anchors, if not nullopt, contains the trust anchor IDs
// (possibly none) the peer requested in ClientHello or CertificateRequest. If
// nullopt, the peer did not send the extension.
std::optional<Array<uint8_t>> peer_requested_trust_anchors;
// peer_available_trust_anchors, if not empty, is the list of trust anchor IDs
// the peer reported as available in EncryptedExtensions. This is only sent by
// servers to clients.
Array<uint8_t> peer_available_trust_anchors;
// cached_x509_ca_names contains a cache of parsed versions of the elements of
// `ca_names`. This pointer is left non-owning so only
// `ssl_crypto_x509_method` needs to link against crypto/x509.
STACK_OF(X509_NAME) *cached_x509_ca_names = nullptr;
// certificate_types, on the client, contains the set of certificate types
// received in a CertificateRequest message.
Array<uint8_t> certificate_types;
// credential is the credential we are using for the handshake.
UniquePtr<SSLCredential> credential;
// peer_pubkey is the public key parsed from the peer's leaf certificate.
UniquePtr<EVP_PKEY> peer_pubkey;
// new_session is the new mutable session being established by the current
// handshake. It should not be cached.
UniquePtr<SSL_SESSION> new_session;
// early_session is the session corresponding to the current 0-RTT state on
// the client if `in_early_data` is true.
UniquePtr<SSL_SESSION> early_session;
// ssl_ech_keys, for servers, is the set of ECH keys to use with this
// handshake. This is copied from `SSL_CTX` to ensure consistent behavior as
// `SSL_CTX` rotates keys.
UniquePtr<SSLECHKeys> ech_keys;
// selected_ech_config, for clients, is the ECHConfig the client uses to offer
// ECH, or nullptr if ECH is not being offered. If non-NULL, `ech_hpke_ctx`
// will be initialized.
UniquePtr<ECHConfig> selected_ech_config;
// new_cipher is the cipher being negotiated in this handshake.
const SSL_CIPHER *new_cipher = nullptr;
// key_block is the record-layer key block for TLS 1.2 and earlier.
Array<uint8_t> key_block;
// hints contains the handshake hints for this connection. If
// `hints_requested` is true, this field is non-null and contains the pending
// hints to filled as the predicted handshake progresses. Otherwise, this
// field, if non-null, contains hints configured by the caller and will
// influence the handshake on match.
UniquePtr<SSL_HANDSHAKE_HINTS> hints;
// ech_is_inner, on the server, indicates whether the ClientHello contained an
// inner ECH extension.
bool ech_is_inner : 1;
// ech_authenticated_reject, on the client, indicates whether an ECH rejection
// handshake has been authenticated.
bool ech_authenticated_reject : 1;
// scts_requested is true if the SCT extension is in the ClientHello.
bool scts_requested : 1;
// handshake_finalized is true once the handshake has completed, at which
// point accessors should use the established state.
bool handshake_finalized : 1;
// accept_psk_mode stores whether the client's PSK mode is compatible with our
// preferences.
bool accept_psk_mode : 1;
// cert_request is true if a client certificate was requested.
bool cert_request : 1;
// certificate_status_expected is true if OCSP stapling was negotiated and the
// server is expected to send a CertificateStatus message. (This is used on
// both the client and server sides.)
bool certificate_status_expected : 1;
// ocsp_stapling_requested is true if a client requested OCSP stapling.
bool ocsp_stapling_requested : 1;
// should_ack_sni is used by a server and indicates that the SNI extension
// should be echoed in the ServerHello.
bool should_ack_sni : 1;
// in_false_start is true if there is a pending client handshake in False
// Start. The client may write data at this point.
bool in_false_start : 1;
// in_early_data is true if there is a pending handshake that has progressed
// enough to send and receive early data.
bool in_early_data : 1;
// early_data_offered is true if the client sent the early_data extension.
bool early_data_offered : 1;
// can_early_read is true if application data may be read at this point in the
// handshake.
bool can_early_read : 1;
// can_early_write is true if application data may be written at this point in
// the handshake.
bool can_early_write : 1;
// is_early_version is true if the protocol version configured is not
// necessarily the final version and is just the predicted 0-RTT version.
bool is_early_version : 1;
// next_proto_neg_seen is one of NPN was negotiated.
bool next_proto_neg_seen : 1;
// ticket_expected is true if a TLS 1.2 NewSessionTicket message is to be sent
// or received.
bool ticket_expected : 1;
// extended_master_secret is true if the extended master secret extension is
// negotiated in this handshake.
bool extended_master_secret : 1;
// pending_private_key_op is true if there is a pending private key operation
// in progress.
bool pending_private_key_op : 1;
// handback indicates that a server should pause the handshake after
// finishing operations that require private key material, in such a way that
// `SSL_get_error` returns `SSL_ERROR_HANDBACK`. It is set by
// `SSL_apply_handoff`.
bool handback : 1;
// hints_requested indicates the caller has requested handshake hints. Only
// the first round-trip of the handshake will complete, after which the
// `hints` structure can be serialized.
bool hints_requested : 1;
// cert_compression_negotiated is true iff `cert_compression_alg_id` is valid.
bool cert_compression_negotiated : 1;
// apply_jdk11_workaround is true if the peer is probably a JDK 11 client
// which implemented TLS 1.3 incorrectly.
bool apply_jdk11_workaround : 1;
// can_release_private_key is true if the private key will no longer be used
// in this handshake.
bool can_release_private_key : 1;
// channel_id_negotiated is true if Channel ID should be used in this
// handshake.
bool channel_id_negotiated : 1;
// received_hello_verify_request is true if we received a HelloVerifyRequest
// message from the server.
bool received_hello_verify_request : 1;
// matched_peer_trust_anchor indicates that we have matched a trust anchor
// the peer requested in the trust anchors extension.
bool matched_peer_trust_anchor : 1;
// peer_matched_trust_anchor is true if the peer indicated a match with one of
// our requested trust anchors.
bool peer_matched_trust_anchor : 1;
// client_version is the value sent or received in the ClientHello version.
uint16_t client_version = 0;
// early_data_read is the amount of early data that has been read by the
// record layer.
uint16_t early_data_read = 0;
// signature_algorithm is the signature algorithm to be used in signing with
// the selected credential, or zero if not applicable or not yet selected.
uint16_t signature_algorithm = 0;
// ech_config_id is the ECH config sent by the client.
uint8_t ech_config_id = 0;
// session_id is the session ID in the ClientHello.
InplaceVector<uint8_t, SSL_MAX_SSL_SESSION_ID_LENGTH> session_id;
// grease_seed is the entropy for GREASE values.
uint8_t grease_seed[ssl_grease_last_index + 1] = {0};
// pake_share is the PAKE message received over the wire, if any.
UniquePtr<SSLPAKEShare> pake_share;
// pake_share_bytes are the bytes of the PAKEShare to send, if any.
Array<uint8_t> pake_share_bytes;
// pake_prover is the PAKE context for a client.
UniquePtr<spake2plus::Prover> pake_prover;
// pake_verifier is the PAKE context for a server.
UniquePtr<spake2plus::Verifier> pake_verifier;
// offered_client_cert_types, for a client, is a list of client certificate
// types (`TLSEXT_cert_type_*` values) that were sent in the
// client_certificate_type extension in the ClientHello.
InplaceVector<uint8_t, kNumCertTypes> offered_client_cert_types;
// peer_cert_type, is the cert type expected from the peer in this handshake,
// negotiated based on server_certificate_type extensions (for a client) or
// client_certificate_type extensions (for a server), or set to X.509
// certificates by default (if the peer didn't send the extension).
// This is not used in resumption.
uint8_t peer_cert_type = kDefaultCertType;
// client_cert_type, for a client, is the cert type for this side of the
// handshake to present to the peer (server) in a Certificate message,
// negotiated based on client_certificate_type extensions.
// This is not used in resumption.
uint8_t client_cert_type = kDefaultCertType;
// client_requested_server_cert_padding_size, for a server, is the number of
// bytes that the client requested we send, or nullopt if the client did not
// request any padding.
std::optional<uint16_t> client_requested_server_padding_size;
};
// kMaxTickets is the maximum number of tickets to send immediately after the
// handshake. We use a one-byte ticket nonce, and there is no point in sending
// so many tickets.
constexpr size_t kMaxTickets = 16;
UniquePtr<SSL_HANDSHAKE> ssl_handshake_new(SSL *ssl);
// ssl_check_message_type checks if `msg` has type `type`. If so it returns
// one. Otherwise, it sends an alert and returns zero.
bool ssl_check_message_type(SSL *ssl, const SSLMessage &msg, int type);
// ssl_run_handshake runs the TLS handshake. It returns one on success and <= 0
// on error. It sets `out_early_return` to one if we've completed the handshake
// early.
int ssl_run_handshake(SSL_HANDSHAKE *hs, bool *out_early_return);
// The following are implementations of `do_handshake` for the client and
// server.
enum ssl_hs_wait_t ssl_client_handshake(SSL_HANDSHAKE *hs);
enum ssl_hs_wait_t ssl_server_handshake(SSL_HANDSHAKE *hs);
enum ssl_hs_wait_t tls13_client_handshake(SSL_HANDSHAKE *hs);
enum ssl_hs_wait_t tls13_server_handshake(SSL_HANDSHAKE *hs);
// The following functions return human-readable representations of the TLS
// handshake states for debugging.
const char *ssl_client_handshake_state(SSL_HANDSHAKE *hs);
const char *ssl_server_handshake_state(SSL_HANDSHAKE *hs);
const char *tls13_client_handshake_state(SSL_HANDSHAKE *hs);
const char *tls13_server_handshake_state(SSL_HANDSHAKE *hs);
// tls13_add_key_update queues a KeyUpdate message on `ssl`. `request_type` must
// be one of `SSL_KEY_UPDATE_REQUESTED` or `SSL_KEY_UPDATE_NOT_REQUESTED`.
bool tls13_add_key_update(SSL *ssl, int request_type);
// tls13_post_handshake processes a post-handshake message. It returns true on
// success and false on failure.
bool tls13_post_handshake(SSL *ssl, const SSLMessage &msg);
bool tls13_process_certificate(SSL_HANDSHAKE *hs, const SSLMessage &msg,
bool allow_anonymous);
bool tls13_process_certificate_verify(SSL_HANDSHAKE *hs, const SSLMessage &msg);
// tls13_process_finished processes `msg` as a Finished message from the
// peer. If `use_saved_value` is true, the verify_data is compared against
// `hs->expected_client_finished` rather than computed fresh.
bool tls13_process_finished(SSL_HANDSHAKE *hs, const SSLMessage &msg,
bool use_saved_value);
bool tls13_add_certificate(SSL_HANDSHAKE *hs);
// tls13_add_certificate_verify adds a TLS 1.3 CertificateVerify message to the
// handshake. If it returns `ssl_private_key_retry`, it should be called again
// to retry when the signing operation is completed.
enum ssl_private_key_result_t tls13_add_certificate_verify(SSL_HANDSHAKE *hs);
bool tls13_add_finished(SSL_HANDSHAKE *hs);
bool tls13_process_new_session_ticket(SSL *ssl, const SSLMessage &msg);
UniquePtr<SSL_SESSION> tls13_create_session_with_ticket(SSL *ssl, CBS *body);
// ssl_setup_extension_permutation computes a ClientHello extension permutation
// for `hs`, if applicable. It returns true on success and false on error.
bool ssl_setup_extension_permutation(SSL_HANDSHAKE *hs);
// ssl_setup_pre_shared_keys computes the offered client PSKs and saves them in
// `hs`. It returns true on success and false on failure.
bool ssl_setup_pre_shared_keys(SSL_HANDSHAKE *hs);
// ssl_setup_key_shares computes client key shares and saves them in `hs`. It
// returns true on success and false on failure. In order of precedence:
//
// - If `override_group_id` is non-zero, it offers a single key share of the
// specified group.
//
// - If a group can be predicted on the basis of a server hint set via
// `SSL_set1_server_supported_groups_hint`, a single key share of that group
// is sent.
//
// - If any number of key shares (including zero) were previously specified by
// the caller via `SSL_set1_client_key_shares`, those are used.
//
// - Otherwise, it selects the first supported group and may select a second if
// at most one of the two is a post-quantum group.
//
// GREASE will be included if enabled, when `override_group_id` is zero.
bool ssl_setup_key_shares(SSL_HANDSHAKE *hs, uint16_t override_group_id);
// ssl_setup_pake_shares computes the client PAKE shares and saves them in `hs`.
// It returns true on success and false on failure.
bool ssl_setup_pake_shares(SSL_HANDSHAKE *hs);
bool ssl_ext_key_share_parse_serverhello(SSL_HANDSHAKE *hs,
Array<uint8_t> *out_secret,
uint8_t *out_alert, CBS *contents);
bool ssl_ext_key_share_parse_clienthello(SSL_HANDSHAKE *hs, bool *out_found,
Span<const uint8_t> *out_peer_key,
uint8_t *out_alert,
const SSL_CLIENT_HELLO *client_hello);
bool ssl_ext_pake_add_serverhello(SSL_HANDSHAKE *hs, CBB *out);
bool ssl_ext_key_share_add_serverhello(SSL_HANDSHAKE *hs, CBB *out);
bool ssl_ext_pake_parse_serverhello(SSL_HANDSHAKE *hs,
Array<uint8_t> *out_secret,
uint8_t *out_alert, CBS *contents);
struct SSLOfferedPSK {
CBS identity, binder;
uint32_t obfuscated_ticket_age;
};
struct SSLOfferedPSKs {
CBS identities, binders;
std::optional<SSLOfferedPSK> Next();
};
const SSLPreSharedKey *ssl_ext_pre_shared_key_parse_serverhello(
SSL_HANDSHAKE *hs, uint8_t *out_alert, CBS *contents);
std::optional<SSLOfferedPSKs> ssl_ext_pre_shared_key_parse_clienthello(
SSL_HANDSHAKE *hs, uint8_t *out_alert, const SSL_CLIENT_HELLO *client_hello,
CBS *contents);
// ssl_verify_psk_binder verifies `client_hello` has a valid binder for `psk`.
// The binder is computed with `client_hello` and `hs`'s transcript, which
// should not have `client_hello` in it. On success, it returns true. Otherwise,
// it returns false and sets `*out_alert` to an alert to send.
//
// This function additionally saves the index where `psk` was found in `hs`. It
// must be called before `ssl_ext_pre_shared_key_add_serverhello`.
bool ssl_verify_psk_binder(SSL_HANDSHAKE *hs, uint8_t *out_alert,
const SSLPreSharedKey &psk,
const SSL_CLIENT_HELLO &client_hello);
bool ssl_ext_pre_shared_key_add_serverhello(SSL_HANDSHAKE *hs, CBB *out);
// ssl_is_sct_list_valid does a shallow parse of the SCT list in `contents` and
// returns whether it's valid.
bool ssl_is_sct_list_valid(const CBS *contents);
// ssl_write_client_hello_without_extensions writes a ClientHello to `out`,
// up to the extensions field. `type` determines the type of ClientHello to
// write. If `omit_session_id` is true, the session ID is empty.
bool ssl_write_client_hello_without_extensions(const SSL_HANDSHAKE *hs,
CBB *cbb,
ssl_client_hello_type_t type,
bool empty_session_id);
// ssl_add_client_hello constructs a ClientHello and adds it to the outgoing
// flight. It returns true on success and false on error.
bool ssl_add_client_hello(SSL_HANDSHAKE *hs);
struct ParsedServerHello {
CBS raw;
uint16_t legacy_version = 0;
CBS random;
CBS session_id;
uint16_t cipher_suite = 0;
uint8_t compression_method = 0;
CBS extensions;
};
// ssl_parse_server_hello parses `msg` as a ServerHello. On success, it writes
// the result to `*out` and returns true. Otherwise, it returns false and sets
// `*out_alert` to an alert to send to the peer.
bool ssl_parse_server_hello(ParsedServerHello *out, uint8_t *out_alert,
const SSLMessage &msg);
enum ssl_cert_verify_context_t {
ssl_cert_verify_server,
ssl_cert_verify_client,
ssl_cert_verify_channel_id,
};
// tls13_get_cert_verify_signature_input generates the message to be signed for
// TLS 1.3's CertificateVerify message. `cert_verify_context` determines the
// type of signature. It sets `*out` to a newly allocated buffer containing the
// result. This function returns true on success and false on failure.
bool tls13_get_cert_verify_signature_input(
SSL_HANDSHAKE *hs, Array<uint8_t> *out,
enum ssl_cert_verify_context_t cert_verify_context);
// ssl_is_valid_alpn_list returns whether `in` is a valid ALPN protocol list.
bool ssl_is_valid_alpn_list(Span<const uint8_t> in);
// ssl_is_alpn_protocol_allowed returns whether `protocol` is a valid server
// selection for `hs->ssl`'s client preferences.
bool ssl_is_alpn_protocol_allowed(const SSL_HANDSHAKE *hs,
Span<const uint8_t> protocol);
// ssl_alpn_list_contains_protocol returns whether `list`, a serialized ALPN
// protocol list, contains `protocol`.
bool ssl_alpn_list_contains_protocol(Span<const uint8_t> list,
Span<const uint8_t> protocol);
// ssl_negotiate_alpn negotiates the ALPN extension, if applicable. It returns
// true on successful negotiation or if nothing was negotiated. It returns false
// and sets `*out_alert` to an alert on error.
bool ssl_negotiate_alpn(SSL_HANDSHAKE *hs, uint8_t *out_alert,
const SSL_CLIENT_HELLO *client_hello);
// ssl_get_local_application_settings looks up the configured ALPS value for
// `protocol`. If found, it sets `*out_settings` to the value and returns true.
// Otherwise, it returns false.
bool ssl_get_local_application_settings(const SSL_HANDSHAKE *hs,
Span<const uint8_t> *out_settings,
Span<const uint8_t> protocol);
// ssl_negotiate_alps negotiates the ALPS extension, if applicable. It returns
// true on successful negotiation or if nothing was negotiated. It returns false
// and sets `*out_alert` to an alert on error.
bool ssl_negotiate_alps(SSL_HANDSHAKE *hs, uint8_t *out_alert,
const SSL_CLIENT_HELLO *client_hello);
// ssl_is_valid_trust_anchor_list returns whether `in` is a valid trust anchor
// identifiers list.
bool ssl_is_valid_trust_anchor_list(Span<const uint8_t> in);
struct SSLExtension {
SSLExtension(uint16_t type_arg, bool allowed_arg = true)
: type(type_arg), allowed(allowed_arg), present(false) {
CBS_init(&data, nullptr, 0);
}
uint16_t type;
bool allowed;
bool present;
CBS data;
};
// ssl_parse_extensions parses a TLS extensions block out of `cbs` and advances
// it. It writes the parsed extensions to pointers in `extensions`. On success,
// it fills in the `present` and `data` fields and returns true. Otherwise, it
// sets `*out_alert` to an alert to send and returns false. Unknown extensions
// are rejected unless `ignore_unknown` is true.
bool ssl_parse_extensions(const CBS *cbs, uint8_t *out_alert,
std::initializer_list<SSLExtension *> extensions,
bool ignore_unknown);
// ssl_verify_peer_cert verifies the peer certificate for `hs`.
enum ssl_verify_result_t ssl_verify_peer_cert(SSL_HANDSHAKE *hs);
// ssl_reverify_peer_cert verifies the peer certificate for `hs` when resuming a
// session.
enum ssl_verify_result_t ssl_reverify_peer_cert(SSL_HANDSHAKE *hs,
bool send_alert);
enum ssl_hs_wait_t ssl_get_finished(SSL_HANDSHAKE *hs);
// ssl_send_finished adds a Finished message to the current flight of messages.
// It returns true on success and false on error.
bool ssl_send_finished(SSL_HANDSHAKE *hs);
// ssl_send_tls12_certificate adds a TLS 1.2 Certificate message to the current
// flight of messages. It returns true on success and false on error.
bool ssl_send_tls12_certificate(SSL_HANDSHAKE *hs);
// ssl_handshake_session returns the `SSL_SESSION` corresponding to the current
// handshake. Note, in TLS 1.2 resumptions, this session is immutable.
const SSL_SESSION *ssl_handshake_session(const SSL_HANDSHAKE *hs);
// ssl_done_writing_client_hello is called after the last ClientHello is written
// by `hs`. It releases some memory that is no longer needed.
void ssl_done_writing_client_hello(SSL_HANDSHAKE *hs);
// ssl_accepts_server_certificate_auth returns whether `hs`, which must be a
// client, accepts certificate-based authentication. If it returns false, the
// client should not send certificate-related extensions, and should not accept
// server responses that result in a certificate-based flow.
bool ssl_accepts_server_certificate_auth(const SSL_HANDSHAKE *hs);
// Flags.
// SSLFlags is a bitmask of flags that can be encoded with the TLS flags
// extension, draft-ietf-tls-tlsflags-14. For now, our in-memory representation
// matches the wire representation, and we only support flags up to 32. If
// higher values are needed, we can increase the size of the bitmask, or only
// store the flags we implement in the bitmask.
using SSLFlags = uint32_t;
inline constexpr SSLFlags kSSLFlagResumptionAcrossNames = 1 << 8;
// ssl_add_flags_extension encodes a tls_flags extension (including the header)
// containing the flags in `flags`. It returns true on success and false on
// error. If `flags` is zero (no flags set), it returns true without adding
// anything to `cbb`.
bool ssl_add_flags_extension(CBB *cbb, SSLFlags flags);
// ssl_parse_flags_extension_request parses tls_flags extension value (excluding
// the header) from `cbs`, for a request message (ClientHello,
// CertificateRequest, or NewSessionTicket). Unrecognized flags will be ignored.
//
// On success, it sets `*out` to the parsed flags and returns true. On error, it
// sets `*out_alert` to a TLS alert and returns false.
bool ssl_parse_flags_extension_request(const CBS *cbs, SSLFlags *out,
uint8_t *out_alert);
// ssl_parse_flags_extension_response parses tls_flags extension value
// (excluding the header) from `cbs`, for a response message (HelloRetryRequest,
// ServerHello, EncryptedExtensions, or Certificate). Only the flags in
// `allowed_flags` may be present.
//
// On success, it sets `*out` to the parsed flags and returns true. On error, it
// sets `*out_alert` to a TLS alert and returns false.
bool ssl_parse_flags_extension_response(const CBS *cbs, SSLFlags *out,
uint8_t *out_alert,
SSLFlags allowed_flags);
// SSLKEYLOGFILE functions.
// ssl_log_secret logs `secret` with label `label`, if logging is enabled for
// `ssl`. It returns true on success and false on failure.
bool ssl_log_secret(const SSL *ssl, const char *label,
Span<const uint8_t> secret);
// ClientHello functions.
bool ssl_parse_client_hello_with_trailing_data(const SSL *ssl, CBS *cbs,
SSL_CLIENT_HELLO *out);
bool ssl_client_hello_get_extension(const SSL_CLIENT_HELLO *client_hello,
CBS *out, uint16_t extension_type);
bool ssl_client_cipher_list_contains_cipher(
const SSL_CLIENT_HELLO *client_hello, uint16_t id);
// GREASE.
// ssl_get_grease_value returns a GREASE value for `hs`. For a given
// connection, the values for each index will be deterministic. This allows the
// same ClientHello be sent twice for a HelloRetryRequest or the same group be
// advertised in both supported_groups and key_shares.
uint16_t ssl_get_grease_value(const SSL_HANDSHAKE *hs,
enum ssl_grease_index_t index);
// Signature algorithms.
// tls1_parse_peer_sigalgs parses `sigalgs` as the list of peer signature
// algorithms and saves them on `hs`. It returns true on success and false on
// error.
bool tls1_parse_peer_sigalgs(SSL_HANDSHAKE *hs, const CBS *sigalgs);
// tls1_get_legacy_signature_algorithm sets `*out` to the signature algorithm
// that should be used with `pkey` in TLS 1.1 and earlier. It returns true on
// success and false if `pkey` may not be used at those versions.
bool tls1_get_legacy_signature_algorithm(uint16_t *out, const EVP_PKEY *pkey);
// tls1_choose_signature_algorithm sets `*out` to a signature algorithm for use
// with `cred` based on the peer's preferences and the algorithms supported. It
// returns true on success and false on error.
bool tls1_choose_signature_algorithm(SSL_HANDSHAKE *hs,
const SSLCredential *cred, uint16_t *out);
// tls12_add_verify_sigalgs adds the signature algorithms acceptable for the
// peer signature to `out`. It returns true on success and false on error.
bool tls12_add_verify_sigalgs(const SSL_HANDSHAKE *hs, CBB *out);
// tls12_check_peer_sigalg checks if `sigalg` is acceptable for the peer
// signature from `pkey`. It returns true on success and false on error, setting
// `*out_alert` to an alert to send.
bool tls12_check_peer_sigalg(const SSL_HANDSHAKE *hs, uint8_t *out_alert,
uint16_t sigalg, EVP_PKEY *pkey);
// Underdocumented functions.
//
// Functions below here haven't been touched up and may be underdocumented.
#define TLSEXT_CHANNEL_ID_SIZE 128
// From RFC 4492, used in encoding the curve type in ECParameters
#define NAMED_CURVE_TYPE 3
struct CERT {
static constexpr bool kAllowUniquePtr = true;
explicit CERT(const SSL_X509_METHOD *x509_method);
~CERT();
bool is_valid() const { return legacy_credential != nullptr; }
// credentials is the list of credentials to select between. Elements of this
// array immutable.
Vector<UniquePtr<SSLCredential>> credentials;
// legacy_credential is the credential configured by the legacy
// non-credential-based APIs. If IsComplete() returns true, it is appended to
// the list of credentials.
UniquePtr<SSLCredential> legacy_credential;
// available_trust_anchors, if not empty, overrides the default list of
// available trust anchors to send in EncryptedExtensions.
Array<uint8_t> available_trust_anchors;
// x509_method contains pointers to functions that might deal with `X509`
// compatibility, or might be a no-op, depending on the application.
const SSL_X509_METHOD *x509_method = nullptr;
// x509_chain may contain a parsed copy of `chain[1..]` from the legacy
// credential. This is only used as a cache in order to implement “get0”
// functions that return a non-owning pointer to the certificate chain.
STACK_OF(X509) *x509_chain = nullptr;
// x509_leaf may contain a parsed copy of the first element of `chain` from
// the legacy credential. This is only used as a cache in order to implement
// “get0” functions that return a non-owning pointer to the certificate chain.
X509 *x509_leaf = nullptr;
// x509_stash contains the last `X509` object append to the legacy
// credential's chain. This is a workaround for some third-party code that
// continue to use an `X509` object even after passing ownership with an
// “add0” function.
X509 *x509_stash = nullptr;
// Certificate setup callback: if set is called whenever a
// certificate may be required (client or server). the callback
// can then examine any appropriate parameters and setup any
// certificates required. This allows advanced applications
// to select certificates on the fly: for example based on
// supported signature algorithms or curves.
int (*cert_cb)(SSL *ssl, void *arg) = nullptr;
void *cert_cb_arg = nullptr;
// Optional X509_STORE for certificate validation. If NULL the parent SSL_CTX
// store is used instead.
X509_STORE *verify_store = nullptr;
// sid_ctx partitions the session space within a shared session cache or
// ticket key. Only sessions with a matching value will be accepted.
InplaceVector<uint8_t, SSL_MAX_SID_CTX_LENGTH> sid_ctx;
};
// `SSL_PROTOCOL_METHOD` abstracts between TLS and DTLS.
struct SSL_PROTOCOL_METHOD {
bool is_dtls;
bool (*ssl_new)(SSL *ssl);
void (*ssl_free)(SSL *ssl);
// get_message sets `*out` to the current handshake message and returns true
// if one has been received. It returns false if more input is needed.
bool (*get_message)(const SSL *ssl, SSLMessage *out);
// next_message is called to release the current handshake message.
void (*next_message)(SSL *ssl);
// has_unprocessed_handshake_data returns whether there is buffered
// handshake data that has not been consumed by `get_message`.
bool (*has_unprocessed_handshake_data)(const SSL *ssl);
// Use the `ssl_open_handshake` wrapper.
ssl_open_record_t (*open_handshake)(SSL *ssl, size_t *out_consumed,
uint8_t *out_alert, Span<uint8_t> in);
// Use the `ssl_open_change_cipher_spec` wrapper.
ssl_open_record_t (*open_change_cipher_spec)(SSL *ssl, size_t *out_consumed,
uint8_t *out_alert,
Span<uint8_t> in);
// Use the `ssl_open_app_data` wrapper.
ssl_open_record_t (*open_app_data)(SSL *ssl, Span<uint8_t> *out,
size_t *out_consumed, uint8_t *out_alert,
Span<uint8_t> in);
// write_app_data encrypts and writes `in` as application data. On success, it
// returns one and sets `*out_bytes_written` to the number of bytes of `in`
// written. Otherwise, it returns <= 0 and sets `*out_needs_handshake` to
// whether the operation failed because the caller needs to drive the
// handshake.
int (*write_app_data)(SSL *ssl, bool *out_needs_handshake,
size_t *out_bytes_written, Span<const uint8_t> in);
int (*dispatch_alert)(SSL *ssl);
// init_message begins a new handshake message of type `type`. `cbb` is the
// root CBB to be passed into `finish_message`. `*body` is set to a child CBB
// the caller should write to. It returns true on success and false on error.
bool (*init_message)(const SSL *ssl, CBB *cbb, CBB *body, uint8_t type);
// finish_message finishes a handshake message. It sets `*out_msg` to the
// serialized message. It returns true on success and false on error.
bool (*finish_message)(const SSL *ssl, CBB *cbb, Array<uint8_t> *out_msg);
// add_message adds a handshake message to the pending flight. It returns
// true on success and false on error.
bool (*add_message)(SSL *ssl, Array<uint8_t> msg);
// add_change_cipher_spec adds a ChangeCipherSpec record to the pending
// flight. It returns true on success and false on error.
bool (*add_change_cipher_spec)(SSL *ssl);
// finish_flight marks the pending flight as finished and ready to send.
// `flush` must be called to write it.
void (*finish_flight)(SSL *ssl);
// schedule_ack schedules a DTLS 1.3 ACK to be sent, without an ACK delay.
// `flush` must be called to write it.
void (*schedule_ack)(SSL *ssl);
// flush writes any scheduled data to the transport. It returns one on success
// and <= 0 on error.
int (*flush)(SSL *ssl);
// on_handshake_complete is called when the handshake is complete.
void (*on_handshake_complete)(SSL *ssl);
// set_read_state sets `ssl`'s read cipher state and level to `aead_ctx` and
// `level`. In QUIC, `aead_ctx` is a placeholder object. In TLS 1.3,
// `traffic_secret` is the original traffic secret. This function returns true
// on success and false on error.
//
// TODO(crbug.com/371998381): Take the traffic secrets as input and let the
// function create the SSLAEADContext.
bool (*set_read_state)(SSL *ssl, ssl_encryption_level_t level,
UniquePtr<SSLAEADContext> aead_ctx,
Span<const uint8_t> traffic_secret);
// set_write_state sets `ssl`'s write cipher state and level to `aead_ctx` and
// `level`. In QUIC, `aead_ctx` is a placeholder object In TLS 1.3,
// `traffic_secret` is the original traffic secret. This function returns true
// on success and false on error.
//
// TODO(crbug.com/371998381): Take the traffic secrets as input and let the
// function create the SSLAEADContext.
bool (*set_write_state)(SSL *ssl, ssl_encryption_level_t level,
UniquePtr<SSLAEADContext> aead_ctx,
Span<const uint8_t> traffic_secret);
};
// The following wrappers call `open_*` but handle `read_shutdown` correctly.
// ssl_open_handshake processes a record from `in` for reading a handshake
// message.
ssl_open_record_t ssl_open_handshake(SSL *ssl, size_t *out_consumed,
uint8_t *out_alert, Span<uint8_t> in);
// ssl_open_change_cipher_spec processes a record from `in` for reading a
// ChangeCipherSpec.
ssl_open_record_t ssl_open_change_cipher_spec(SSL *ssl, size_t *out_consumed,
uint8_t *out_alert,
Span<uint8_t> in);
// ssl_open_app_data processes a record from `in` for reading application data.
// On success, it returns `ssl_open_record_success` and sets `*out` to the
// input. If it encounters a post-handshake message, it returns
// `ssl_open_record_discard`. The caller should then retry, after processing any
// messages received with `get_message`.
ssl_open_record_t ssl_open_app_data(SSL *ssl, Span<uint8_t> *out,
size_t *out_consumed, uint8_t *out_alert,
Span<uint8_t> in);
struct SSL_X509_METHOD {
// check_CA_list returns one if `names` is a good list of X.509 distinguished
// names and zero otherwise. This is used to ensure that we can reject
// unparsable values at handshake time when using crypto/x509.
bool (*check_CA_list)(STACK_OF(CRYPTO_BUFFER) *names);
// cert_clear frees and NULLs all X509 certificate-related state.
void (*cert_clear)(CERT *cert);
// cert_free frees all X509-related state.
void (*cert_free)(CERT *cert);
// cert_flush_cached_chain drops any cached `X509`-based certificate chain
// from `cert`.
// cert_dup duplicates any needed fields from `cert` to `new_cert`.
void (*cert_dup)(CERT *new_cert, const CERT *cert);
void (*cert_flush_cached_chain)(CERT *cert);
// cert_flush_cached_chain drops any cached `X509`-based leaf certificate
// from `cert`.
void (*cert_flush_cached_leaf)(CERT *cert);
// session_cache_objects fills out `sess->x509_peer` and `sess->x509_chain`
// from `sess->certs` and erases `sess->x509_chain_without_leaf`. It returns
// true on success or false on error.
bool (*session_cache_objects)(SSL_SESSION *session);
// session_dup duplicates any needed fields from `session` to `new_session`.
// It returns true on success or false on error.
bool (*session_dup)(SSL_SESSION *new_session, const SSL_SESSION *session);
// session_clear frees any X509-related state from `session`.
void (*session_clear)(SSL_SESSION *session);
// session_verify_cert_chain verifies the certificate chain in `session`,
// sets `session->verify_result` and returns true on success or false on
// error.
bool (*session_verify_cert_chain)(SSL_SESSION *session, SSL_HANDSHAKE *ssl,
uint8_t *out_alert);
// hs_flush_cached_ca_names drops any cached `X509_NAME`s from `hs`.
void (*hs_flush_cached_ca_names)(SSL_HANDSHAKE *hs);
// ssl_new does any necessary initialisation of `hs`. It returns true on
// success or false on error.
bool (*ssl_new)(SSL_HANDSHAKE *hs);
// ssl_free frees anything created by `ssl_new`.
void (*ssl_config_free)(SSL_CONFIG *cfg);
// ssl_flush_cached_client_CA drops any cached `X509_NAME`s from `ssl`.
void (*ssl_flush_cached_client_CA)(SSL_CONFIG *cfg);
// ssl_auto_chain_if_needed runs the deprecated auto-chaining logic if
// necessary. On success, it updates `ssl`'s certificate configuration as
// needed and returns true. Otherwise, it returns false.
bool (*ssl_auto_chain_if_needed)(SSL_HANDSHAKE *hs);
// ssl_ctx_new does any necessary initialisation of `ctx`. It returns true on
// success or false on error.
bool (*ssl_ctx_new)(SSLContext *ctx);
// ssl_ctx_free frees anything created by `ssl_ctx_new`.
void (*ssl_ctx_free)(SSLContext *ctx);
// ssl_ctx_flush_cached_client_CA drops any cached `X509_NAME`s from `ctx`.
void (*ssl_ctx_flush_cached_client_CA)(SSLContext *ssl);
};
// ssl_crypto_x509_method provides the `SSL_X509_METHOD` functions using
// crypto/x509.
extern const SSL_X509_METHOD ssl_crypto_x509_method;
// ssl_noop_x509_method provides the `SSL_X509_METHOD` functions that avoid
// crypto/x509.
extern const SSL_X509_METHOD ssl_noop_x509_method;
struct TicketKey {
static constexpr bool kAllowUniquePtr = true;
uint8_t name[SSL_TICKET_KEY_NAME_LEN] = {0};
uint8_t hmac_key[16] = {0};
uint8_t aes_key[16] = {0};
// next_rotation_tv_sec is the time (in seconds from the epoch) when the
// current key should be superseded by a new key, or the time when a previous
// key should be dropped. If zero, then the key should not be automatically
// rotated.
uint64_t next_rotation_tv_sec = 0;
};
struct CertCompressionAlg {
static constexpr bool kAllowUniquePtr = true;
ssl_cert_compression_func_t compress = nullptr;
ssl_cert_decompression_func_t decompress = nullptr;
uint16_t alg_id = 0;
};
DEFINE_LHASH_OF(SSL_SESSION)
// An ssl_shutdown_t describes the shutdown state of one end of the connection,
// whether it is alive or has been shutdown via close_notify or fatal alert.
enum ssl_shutdown_t {
ssl_shutdown_none = 0,
ssl_shutdown_close_notify = 1,
ssl_shutdown_error = 2,
};
enum ssl_ech_status_t {
// ssl_ech_none indicates ECH was not offered, or we have not gotten far
// enough in the handshake to determine the status.
ssl_ech_none,
// ssl_ech_accepted indicates the server accepted ECH.
ssl_ech_accepted,
// ssl_ech_rejected indicates the server was offered ECH but rejected it.
ssl_ech_rejected,
};
struct SSL3_STATE {
static constexpr bool kAllowUniquePtr = true;
SSL3_STATE();
~SSL3_STATE();
uint64_t read_sequence = 0;
uint64_t write_sequence = 0;
uint8_t server_random[SSL3_RANDOM_SIZE] = {0};
uint8_t client_random[SSL3_RANDOM_SIZE] = {0};
// read_buffer holds data from the transport to be processed.
SSLBuffer read_buffer;
// write_buffer holds data to be written to the transport.
SSLBuffer write_buffer;
// pending_app_data is the unconsumed application data. It points into
// `read_buffer`.
Span<uint8_t> pending_app_data;
// unreported_bytes_written is the number of bytes successfully written to the
// transport, but not yet reported to the caller. The next `SSL_write` will
// skip this many bytes from the input. This is used if
// `SSL_MODE_ENABLE_PARTIAL_WRITE` is disabled, in which case `SSL_write` only
// reports bytes written when the full caller input is written.
size_t unreported_bytes_written = 0;
// pending_write, if `has_pending_write` is true, is the caller-supplied data
// corresponding to the current pending write. This is used to check the
// caller retried with a compatible buffer.
Span<const uint8_t> pending_write;
// pending_write_type, if `has_pending_write` is true, is the record type
// for the current pending write.
//
// TODO(davidben): Remove this when alerts are moved out of this write path.
uint8_t pending_write_type = 0;
// read_shutdown is the shutdown state for the read half of the connection.
enum ssl_shutdown_t read_shutdown = ssl_shutdown_none;
// write_shutdown is the shutdown state for the write half of the connection.
enum ssl_shutdown_t write_shutdown = ssl_shutdown_none;
// read_error, if `read_shutdown` is `ssl_shutdown_error`, is the error for
// the receive half of the connection.
UniquePtr<ERR_SAVE_STATE> read_error;
int total_renegotiations = 0;
// This holds a variable that indicates what we were doing when a 0 or -1 is
// returned. This is needed for non-blocking IO so we know what request
// needs re-doing when in SSL_accept or SSL_connect
int rwstate = SSL_ERROR_NONE;
enum ssl_encryption_level_t quic_read_level = ssl_encryption_initial;
enum ssl_encryption_level_t quic_write_level = ssl_encryption_initial;
// version is the protocol version, or zero if the version has not yet been
// set. In clients offering 0-RTT, this version will initially be set to the
// early version, then switched to the final version. To distinguish these
// cases, use `ssl_has_final_version`.
uint16_t version = 0;
// early_data_skipped is the amount of early data that has been skipped by the
// record layer.
uint16_t early_data_skipped = 0;
// empty_record_count is the number of consecutive empty records received.
uint8_t empty_record_count = 0;
// warning_alert_count is the number of consecutive warning alerts
// received.
uint8_t warning_alert_count = 0;
// key_update_count is the number of consecutive KeyUpdates received.
uint8_t key_update_count = 0;
// ech_status indicates whether ECH was accepted by the server.
ssl_ech_status_t ech_status = ssl_ech_none;
// skip_early_data instructs the record layer to skip unexpected early data
// messages when 0RTT is rejected.
bool skip_early_data : 1;
// v2_hello_done is true if the peer's V2ClientHello, if any, has been handled
// and future messages should use the record layer.
bool v2_hello_done : 1;
// is_v2_hello is true if the current handshake message was derived from a
// V2ClientHello rather than received from the peer directly.
bool is_v2_hello : 1;
// has_message is true if the current handshake message has been returned
// at least once by `get_message` and false otherwise.
bool has_message : 1;
// initial_handshake_complete is true if the initial handshake has
// completed.
bool initial_handshake_complete : 1;
// session_reused indicates whether a session was resumed.
bool session_reused : 1;
bool send_connection_binding : 1;
// channel_id_valid is true if, on the server, the client has negotiated a
// Channel ID and the `channel_id` field is filled in.
bool channel_id_valid : 1;
// key_update_pending is true if we are in the process of sending a KeyUpdate
// message. As a DoS mitigation (and a requirement in DTLS), we never send
// more than one KeyUpdate at once. In DTLS, this tracks whether there is an
// unACKed KeyUpdate.
bool key_update_pending : 1;
// early_data_accepted is true if early data was accepted by the server.
bool early_data_accepted : 1;
// alert_dispatch is true there is an alert in `send_alert` to be sent.
bool alert_dispatch : 1;
// renegotiate_pending is whether the read half of the channel is blocked on a
// HelloRequest.
bool renegotiate_pending : 1;
// used_hello_retry_request is whether the handshake used a TLS 1.3
// HelloRetryRequest message.
bool used_hello_retry_request : 1;
// was_key_usage_invalid is whether the handshake succeeded despite using a
// TLS mode which was incompatible with the leaf certificate's keyUsage
// extension.
bool was_key_usage_invalid : 1;
// server_sent_requested_padding is true iff a client requested padding
// through the server padding extension, and the server sent back the
// requested amount of padding.
bool server_sent_requested_padding : 1;
// hs_buf is the buffer of handshake data to process.
UniquePtr<BUF_MEM> hs_buf;
// pending_hs_data contains the pending handshake data that has not yet
// been encrypted to `pending_flight`. This allows packing the handshake into
// fewer records.
UniquePtr<BUF_MEM> pending_hs_data;
// pending_flight is the pending outgoing flight. This is used to flush each
// handshake flight in a single write. `write_buffer` must be written out
// before this data.
UniquePtr<BUF_MEM> pending_flight;
// pending_flight_offset is the number of bytes of `pending_flight` which have
// been successfully written.
uint32_t pending_flight_offset = 0;
// ticket_age_skew is the difference, in seconds, between the client-sent
// ticket age and the server-computed value in TLS 1.3 server connections
// which resumed a session.
int32_t ticket_age_skew = 0;
// ssl_early_data_reason stores details on why 0-RTT was accepted or rejected.
enum ssl_early_data_reason_t early_data_reason = ssl_early_data_unknown;
// aead_read_ctx is the current read cipher state.
UniquePtr<SSLAEADContext> aead_read_ctx;
// aead_write_ctx is the current write cipher state.
UniquePtr<SSLAEADContext> aead_write_ctx;
// hs is the handshake state for the current handshake or NULL if there isn't
// one.
UniquePtr<SSL_HANDSHAKE> hs;
InplaceVector<uint8_t, SSL_MAX_MD_SIZE> write_traffic_secret;
InplaceVector<uint8_t, SSL_MAX_MD_SIZE> read_traffic_secret;
InplaceVector<uint8_t, SSL_MAX_MD_SIZE> exporter_secret;
// Connection binding to prevent renegotiation attacks
InplaceVector<uint8_t, 12> previous_client_finished;
InplaceVector<uint8_t, 12> previous_server_finished;
uint8_t send_alert[2] = {0};
// established_session is the session established by the connection. This
// session is only filled upon the completion of the handshake and is
// immutable.
UniquePtr<SSL_SESSION> established_session;
// Next protocol negotiation. For the client, this is the protocol that we
// sent in NextProtocol and is set when handling ServerHello extensions.
//
// For a server, this is the client's selected_protocol from NextProtocol and
// is set when handling the NextProtocol message, before the Finished
// message.
Array<uint8_t> next_proto_negotiated;
// ALPN information
// (we are in the process of transitioning from NPN to ALPN.)
// In a server these point to the selected ALPN protocol after the
// ClientHello has been processed. In a client these contain the protocol
// that the server selected once the ServerHello has been processed.
Array<uint8_t> alpn_selected;
// hostname, on the server, is the value of the SNI extension.
UniquePtr<char> hostname;
// For a server:
// If `channel_id_valid` is true, then this contains the
// verified Channel ID from the client: a P256 point, (x,y), where
// each are big-endian values.
uint8_t channel_id[64] = {0};
// Contains the QUIC transport params received by the peer.
Array<uint8_t> peer_quic_transport_params;
// srtp_profile is the selected SRTP protection profile for
// DTLS-SRTP.
const SRTP_PROTECTION_PROFILE *srtp_profile = nullptr;
};
// lengths of messages
#define DTLS1_RT_MAX_HEADER_LENGTH 13
// DTLS_PLAINTEXT_RECORD_HEADER_LENGTH is the length of the DTLS record header
// for plaintext records (in DTLS 1.3) or DTLS versions <= 1.2.
#define DTLS_PLAINTEXT_RECORD_HEADER_LENGTH 13
// DTLS1_3_RECORD_HEADER_LENGTH is the length of the DTLS 1.3 record header
// sent by BoringSSL for encrypted records. Note that received encrypted DTLS
// 1.3 records might have a different length header.
#define DTLS1_3_RECORD_HEADER_WRITE_LENGTH 5
static_assert(DTLS1_RT_MAX_HEADER_LENGTH >= DTLS_PLAINTEXT_RECORD_HEADER_LENGTH,
"DTLS1_RT_MAX_HEADER_LENGTH must not be smaller than defined "
"record header lengths");
static_assert(DTLS1_RT_MAX_HEADER_LENGTH >= DTLS1_3_RECORD_HEADER_WRITE_LENGTH,
"DTLS1_RT_MAX_HEADER_LENGTH must not be smaller than defined "
"record header lengths");
#define DTLS1_HM_HEADER_LENGTH 12
// A DTLSMessageBitmap maintains a list of bits which may be marked to indicate
// a portion of a message was received or ACKed.
class DTLSMessageBitmap {
public:
// A Range represents a range of bits from `start`, inclusive, to `end`,
// exclusive.
struct Range {
size_t start = 0;
size_t end = 0;
bool empty() const { return start == end; }
size_t size() const { return end - start; }
bool operator==(const Range &r) const {
return start == r.start && end == r.end;
}
bool operator!=(const Range &r) const { return !(*this == r); }
};
// Init initializes the structure with `num_bits` unmarked bits, from zero
// to `num_bits - 1`.
bool Init(size_t num_bits);
// MarkRange marks the bits from `start`, inclusive, to `end`, exclusive.
void MarkRange(size_t start, size_t end);
// NextUnmarkedRange returns the next range of unmarked bits, starting from
// `start`, inclusive. If all bits after `start` are marked, it returns an
// empty range.
Range NextUnmarkedRange(size_t start) const;
// IsComplete returns whether every bit in the bitmask has been marked.
bool IsComplete() const { return bytes_.empty(); }
private:
// bytes_ contains the unmarked bits. We maintain an invariant: if `bytes_` is
// not empty, some bit is unset.
Array<uint8_t> bytes_;
// first_unmarked_byte_ is the index of first byte in `bytes_` that is not
// 0xff. This is maintained to amortize checking if the message is complete.
size_t first_unmarked_byte_ = 0;
};
struct hm_header_st {
uint8_t type;
uint32_t msg_len;
uint16_t seq;
uint32_t frag_off;
uint32_t frag_len;
};
// An DTLSIncomingMessage is an incoming DTLS message, possibly not yet
// assembled.
struct DTLSIncomingMessage {
static constexpr bool kAllowUniquePtr = true;
Span<uint8_t> msg() { return Span(data).subspan(DTLS1_HM_HEADER_LENGTH); }
Span<const uint8_t> msg() const {
return Span(data).subspan(DTLS1_HM_HEADER_LENGTH);
}
size_t msg_len() const { return msg().size(); }
// type is the type of the message.
uint8_t type = 0;
// seq is the sequence number of this message.
uint16_t seq = 0;
// data contains the message, including the message header of length
// `DTLS1_HM_HEADER_LENGTH`.
Array<uint8_t> data;
// reassembly tracks which parts of the message have been received.
DTLSMessageBitmap reassembly;
};
struct DTLSOutgoingMessage {
size_t msg_len() const {
assert(!is_ccs);
assert(data.size() >= DTLS1_HM_HEADER_LENGTH);
return data.size() - DTLS1_HM_HEADER_LENGTH;
}
bool IsFullyAcked() const {
// ACKs only exist in DTLS 1.3, which does not send ChangeCipherSpec.
return !is_ccs && acked.IsComplete();
}
Array<uint8_t> data;
uint16_t epoch = 0;
bool is_ccs = false;
// acked tracks which bits of the message have been ACKed by the peer. If
// `msg_len` is zero, it tracks one bit for whether the header has been
// received.
DTLSMessageBitmap acked;
};
struct OPENSSL_timeval {
uint64_t tv_sec;
uint32_t tv_usec;
};
struct DTLSTimer {
public:
static constexpr uint64_t kNever = UINT64_MAX;
// StartMicroseconds schedules the timer to expire the specified number of
// microseconds from `now`.
void StartMicroseconds(OPENSSL_timeval now, uint64_t microseconds);
// Stop disables the timer.
void Stop();
// IsExpired returns true if the timer was set and is expired at time `now`.
bool IsExpired(OPENSSL_timeval now) const;
// IsSet returns true if the timer is scheduled or expired, and false if it is
// stopped.
bool IsSet() const;
void UpdateDuration(uint64_t microseconds) { duration_ = microseconds; }
// MicrosecondsRemaining returns the time remaining, in microseconds, at
// `now`, or `kNever` if the timer is unset.
uint64_t MicrosecondsRemaining(OPENSSL_timeval now) const;
private:
uint64_t start_time_;
uint64_t duration_ = kNever; // If set to kNever then this timer is unset.
};
// DTLS_MAX_EXTRA_WRITE_EPOCHS is the maximum number of additional write epochs
// that DTLS may need to retain.
//
// The maximum is, as a DTLS 1.3 server, immediately after sending Finished. At
// this point, the current epoch is the application write keys (epoch 3), but we
// may have ServerHello (epoch 0) and EncryptedExtensions (epoch 1) to
// retransmit. KeyUpdate does not increase this count. If the server were to
// initiate KeyUpdate from this state, it would not apply the new epoch until
// the client's ACKs have caught up. At that point, epochs 0 and 1 can be
// discarded.
#define DTLS_MAX_EXTRA_WRITE_EPOCHS 2
// DTLS_MAX_ACK_BUFFER is the maximum number of records worth of data we'll keep
// track of with DTLS 1.3 ACKs. When we exceed this value, information about
// stale records will be dropped. This will not break the connection but may
// cause ACKs to perform worse and retransmit unnecessary information.
#define DTLS_MAX_ACK_BUFFER 32
// A DTLSSentRecord records information about a record we sent. Each record
// covers all bytes from `first_msg_start` (inclusive) of `first_msg` to
// `last_msg_end` (exclusive) of `last_msg`. Messages are referenced by index
// into `outgoing_messages`. `last_msg_end` may be `outgoing_messages.size()` if
// `last_msg_end` is zero.
//
// When the message is empty, `first_msg_start` and `last_msg_end` are
// maintained as if there is a single bit in the message representing the
// header. See `acked` in DTLSOutgoingMessage.
struct DTLSSentRecord {
DTLSRecordNumber number;
PackedSize<SSL_MAX_HANDSHAKE_FLIGHT> first_msg = 0;
PackedSize<SSL_MAX_HANDSHAKE_FLIGHT> last_msg = 0;
uint32_t first_msg_start = 0;
uint32_t last_msg_end = 0;
};
enum class QueuedKeyUpdate {
kNone,
kUpdateNotRequested,
kUpdateRequested,
};
// DTLS_PREV_READ_EPOCH_EXPIRE_SECONDS is how long to retain the previous read
// epoch in DTLS 1.3. This value is set based on the following:
//
// - Section 4.2.1 of RFC 9147 recommends retaining past read epochs for the
// default TCP MSL. This accommodates packet reordering with KeyUpdate.
//
// - Section 5.8.1 of RFC 9147 requires being capable of ACKing the client's
// final flight for at least twice the default MSL. That requires retaining
// epoch 2 after the handshake.
//
// - Section 4 of RFC 9293 defines the MSL to be two minutes.
#define DTLS_PREV_READ_EPOCH_EXPIRE_SECONDS (4 * 60)
struct DTLSPrevReadEpoch {
static constexpr bool kAllowUniquePtr = true;
DTLSReadEpoch epoch;
// expire is the expiration time of the read epoch, expressed as a POSIX
// timestamp in seconds.
uint64_t expire;
};
struct DTLS1_STATE {
static constexpr bool kAllowUniquePtr = true;
DTLS1_STATE();
~DTLS1_STATE();
bool Init();
// has_change_cipher_spec is true if we have received a ChangeCipherSpec from
// the peer in this epoch.
bool has_change_cipher_spec : 1;
// outgoing_messages_complete is true if `outgoing_messages` has been
// completed by an attempt to flush it. Future calls to `add_message` and
// `add_change_cipher_spec` will start a new flight.
bool outgoing_messages_complete : 1;
// flight_has_reply is true if the current outgoing flight is complete and has
// processed at least one message. This is used to detect whether we or the
// peer sent the final flight.
bool flight_has_reply : 1;
// handshake_write_overflow and handshake_read_overflow are true if
// handshake_write_seq and handshake_read_seq, respectively have overflowed.
bool handshake_write_overflow : 1;
bool handshake_read_overflow : 1;
// sending_flight and sending_ack are true if we are in the process of sending
// a handshake flight and ACK, respectively.
bool sending_flight : 1;
bool sending_ack : 1;
// pending_flush is whether we have a pending flush on the transport.
bool pending_flush : 1;
// queued_key_update, if not kNone, indicates we've queued a KeyUpdate message
// to send after the current flight is ACKed.
QueuedKeyUpdate queued_key_update : 2;
uint16_t handshake_write_seq = 0;
uint16_t handshake_read_seq = 0;
// read_epoch is the current read epoch.
DTLSReadEpoch read_epoch;
// next_read_epoch is the next read epoch in DTLS 1.3. It will become
// current once a record is received from it.
UniquePtr<DTLSReadEpoch> next_read_epoch;
// prev_read_epoch is the previous read epoch in DTLS 1.3.
UniquePtr<DTLSPrevReadEpoch> prev_read_epoch;
// write_epoch is the current DTLS write epoch. Non-retransmit records will
// generally use this epoch.
// TODO(crbug.com/381113363): 0-RTT will be the exception, when implemented.
DTLSWriteEpoch write_epoch;
// extra_write_epochs is the collection available write epochs.
InplaceVector<UniquePtr<DTLSWriteEpoch>, DTLS_MAX_EXTRA_WRITE_EPOCHS>
extra_write_epochs;
// incoming_messages is a ring buffer of incoming handshake messages that have
// yet to be processed. The front of the ring buffer is message number
// `handshake_read_seq`, at position `handshake_read_seq` %
// `SSL_MAX_HANDSHAKE_FLIGHT`.
UniquePtr<DTLSIncomingMessage> incoming_messages[SSL_MAX_HANDSHAKE_FLIGHT];
// outgoing_messages is the queue of outgoing messages from the last handshake
// flight.
InplaceVector<DTLSOutgoingMessage, SSL_MAX_HANDSHAKE_FLIGHT>
outgoing_messages;
// sent_records is a queue of records we sent, for processing ACKs. To save
// memory in the steady state, the structure is stored on the heap and dropped
// when empty.
UniquePtr<MRUQueue<DTLSSentRecord, DTLS_MAX_ACK_BUFFER>> sent_records;
// records_to_ack is a queue of received records that we should ACK. This is
// not stored on the heap because, in the steady state, DTLS 1.3 does not
// necessarily empty this list. (We probably could drop records from here once
// they are sufficiently old.)
MRUQueue<DTLSRecordNumber, DTLS_MAX_ACK_BUFFER> records_to_ack;
// outgoing_written is the number of outgoing messages that have been
// written.
uint8_t outgoing_written = 0;
// outgoing_offset is the number of bytes of the next outgoing message have
// been written.
uint32_t outgoing_offset = 0;
unsigned mtu = 0; // max DTLS packet size
// num_timeouts is the number of times the retransmit timer has fired since
// the last time it was reset.
unsigned num_timeouts = 0;
// retransmit_timer tracks when to schedule the next DTLS retransmit if we do
// not hear from the peer.
DTLSTimer retransmit_timer;
// ack_timer tracks when to send an ACK.
DTLSTimer ack_timer;
// timeout_duration_ms is the timeout duration in milliseconds.
uint32_t timeout_duration_ms = 0;
};
// An ALPSConfig is a pair of ALPN protocol and settings value to use with ALPS.
struct ALPSConfig {
Array<uint8_t> protocol;
Array<uint8_t> settings;
};
// SSL_CONFIG contains configuration bits that can be shed after the handshake
// completes. Objects of this type are not shared; they are unique to a
// particular `SSL`.
//
// See SSL_shed_handshake_config() for more about the conditions under which
// configuration can be shed.
struct SSL_CONFIG {
static constexpr bool kAllowUniquePtr = true;
explicit SSL_CONFIG(SSL *ssl_arg);
~SSL_CONFIG();
// ssl is a non-owning pointer to the parent `SSL` object.
SSL *const ssl = nullptr;
// conf_max_version is the maximum acceptable version configured by
// `SSL_set_max_proto_version`. Note this version is not normalized in DTLS
// and is further constrained by `SSL_OP_NO_*`.
uint16_t conf_max_version = 0;
// conf_min_version is the minimum acceptable version configured by
// `SSL_set_min_proto_version`. Note this version is not normalized in DTLS
// and is further constrained by `SSL_OP_NO_*`.
uint16_t conf_min_version = 0;
X509_VERIFY_PARAM *param = nullptr;
// crypto
UniquePtr<SSLCipherPreferenceList> cipher_list;
// This is used to hold the local certificate used (i.e. the server
// certificate for a server or the client certificate for a client).
UniquePtr<CERT> cert;
int (*verify_callback)(int ok,
X509_STORE_CTX *ctx) =
nullptr; // fail if callback returns 0
enum ssl_verify_result_t (*custom_verify_callback)(
SSL *ssl, uint8_t *out_alert) = nullptr;
// Server-only: psk_identity_hint is the identity hint to send in
// PSK-based key exchanges.
UniquePtr<char> psk_identity_hint;
unsigned (*psk_client_callback)(SSL *ssl, const char *hint, char *identity,
unsigned max_identity_len, uint8_t *psk,
unsigned max_psk_len) = nullptr;
unsigned (*psk_server_callback)(SSL *ssl, const char *identity, uint8_t *psk,
unsigned max_psk_len) = nullptr;
// for server side, keep the list of CA_dn we can use
UniquePtr<STACK_OF(CRYPTO_BUFFER)> client_CA;
// cached_x509_client_CA is a cache of parsed versions of the elements of
// `client_CA`.
STACK_OF(X509_NAME) *cached_x509_client_CA = nullptr;
// For client side, keep the list of CA distinguished names we can use
// for the Certificate Authorities extension.
// TODO(bbe) having this separate from the client side (above) is mildly
// silly, but OpenSSL has *_client_CA API's for this exposed, and for the
// moment we are not crossing those streams.
UniquePtr<STACK_OF(CRYPTO_BUFFER)> CA_names;
// Trust anchor IDs to be requested in the trust_anchors extension.
std::optional<Array<uint8_t>> requested_trust_anchors;
// Our list of supported groups. If this list is modified, for a client,
// `client_key_share_selections` must be reset if the key shares are no longer
// a valid subsequence of the supported group list.
Array<uint16_t> supported_group_list;
// Contains flags corresponding to `supported_group_list`, which are
// SSL_GROUP_FLAG_* values ORed together.
Array<uint32_t> supported_group_list_flags;
// For a client, this may contain a subsequence of the group IDs in
// `suppported_group_list`, which gives the groups for which key shares should
// be sent in the client's key_share extension. This is non-nullopt iff
// `SSL_set1_client_key_shares` was successfully called to configure key
// shares. If non-nullopt, these groups are in the same order as they appear
// in `supported_group_list`, and may not contain duplicates.
std::optional<InplaceVector<uint16_t, kNumNamedGroups>>
client_key_share_selections;
// For a client, this contains a list of groups believed to be supported by
// the server, in server preference order.
Array<uint16_t> server_supported_groups_hint;
// channel_id_private is the client's Channel ID private key, or null if
// Channel ID should not be offered on this connection.
UniquePtr<EVP_PKEY> channel_id_private;
// For a client, this contains the list of supported protocols in wire
// format.
Array<uint8_t> alpn_client_proto_list;
// alps_configs contains the list of supported protocols to use with ALPS,
// along with their corresponding ALPS values.
Vector<ALPSConfig> alps_configs;
// Contains the QUIC transport params that this endpoint will send.
Array<uint8_t> quic_transport_params;
// Contains the context used to decide whether to accept early data in QUIC.
Array<uint8_t> quic_early_data_context;
// verify_sigalgs, if not empty, is the set of signature algorithms
// accepted from the peer in decreasing order of preference.
Array<uint16_t> verify_sigalgs;
// srtp_profiles is the list of configured SRTP protection profiles for
// DTLS-SRTP.
UniquePtr<STACK_OF(SRTP_PROTECTION_PROFILE)> srtp_profiles;
// client_ech_config_list, if not empty, is a serialized ECHConfigList
// structure for the client to use when negotiating ECH.
Array<uint8_t> client_ech_config_list;
// compliance_policy limits the set of ciphers that can be selected when
// negotiating a TLS 1.3 connection.
enum ssl_compliance_policy_t compliance_policy = ssl_compliance_policy_none;
// server_padding_request, if set by the client, indicates that the client
// will ask the server to include additional padding in the
// EncryptedExtensions message of a TLS 1.3 connection.
std::optional<uint16_t> server_padding_request;
// verify_mode is a bitmask of `SSL_VERIFY_*` values.
uint8_t verify_mode = SSL_VERIFY_NONE;
// accepted_peer_cert_types contains a list of `TLSEXT_cert_type_*` values in
// preference order indicating the types of certificates to accept from the
// peer. This list should always be non-empty. If the caller did not configure
// a valid list, only X.509 certificates are accepted by default.
InplaceVector<uint8_t, kNumCertTypes> accepted_peer_cert_types;
// available_client_cert_types, if not empty, contains a list of
// `TLSEXT_cert_type_*` values in preference order indicating the types of
// client certificates that the caller, as a client, explicitly configured and
// wishes to advertise, instead of the automatically inferred client cert
// types from the configured credential list.
InplaceVector<uint8_t, kNumCertTypes> available_client_cert_types;
// ech_grease_enabled controls whether ECH GREASE may be sent in the
// ClientHello.
bool ech_grease_enabled : 1;
// Enable signed certificate time stamps. Currently client only.
bool signed_cert_timestamps_enabled : 1;
// ocsp_stapling_enabled is only used by client connections and indicates
// whether OCSP stapling will be requested.
bool ocsp_stapling_enabled : 1;
// channel_id_enabled is copied from the `SSL_CTX`. For a server, it means
// that we'll accept Channel IDs from clients. It is ignored on the client.
bool channel_id_enabled : 1;
// If enforce_rsa_key_usage is true, the handshake will fail if the
// keyUsage extension is present and incompatible with the TLS usage.
// This field is not read until after certificate verification.
bool enforce_rsa_key_usage : 1;
// retain_only_sha256_of_client_certs is true if we should compute the SHA256
// hash of the peer's certificate and then discard it to save memory and
// session space. Only effective on the server side.
bool retain_only_sha256_of_client_certs : 1;
// handoff indicates that a server should stop after receiving the
// ClientHello and pause the handshake in such a way that `SSL_get_error`
// returns `SSL_ERROR_HANDOFF`. This is copied in `SSL_new` from the `SSL_CTX`
// element of the same name and may be cleared if the handoff is declined.
bool handoff : 1;
// shed_handshake_config indicates that the handshake config (this object!)
// should be freed after the handshake completes.
bool shed_handshake_config : 1;
// jdk11_workaround is whether to disable TLS 1.3 for JDK 11 clients, as a
// workaround for https://bugs.openjdk.java.net/browse/JDK-8211806.
bool jdk11_workaround : 1;
// QUIC drafts up to and including 32 used a different TLS extension
// codepoint to convey QUIC's transport parameters.
bool quic_use_legacy_codepoint : 1;
// permute_extensions is whether to permute extensions when sending messages.
bool permute_extensions : 1;
// aes_hw_override if set indicates we should override checking for aes
// hardware support, and use the value in aes_hw_override_value instead.
bool aes_hw_override : 1;
// aes_hw_override_value is used for testing to indicate the support or lack
// of support for AES hw. The value is only considered if `aes_hw_override` is
// true.
bool aes_hw_override_value : 1;
// alps_use_new_codepoint if set indicates we use new ALPS extension codepoint
// to negotiate and convey application settings.
bool alps_use_new_codepoint : 1;
// server_padding_enabled is true iff the server is willing to send additional
// padding to clients that request it through the server padding extension.
bool server_padding_enabled : 1;
};
// From RFC 8446, used in determining PSK modes.
#define SSL_PSK_DHE_KE 0x1
// kMaxEarlyDataAccepted is the advertised number of plaintext bytes of early
// data that will be accepted. This value should be slightly below
// kMaxEarlyDataSkipped in tls_record.c, which is measured in ciphertext.
static const size_t kMaxEarlyDataAccepted = 14336;
UniquePtr<CERT> ssl_cert_dup(CERT *cert);
bool ssl_set_cert(CERT *cert, UniquePtr<CRYPTO_BUFFER> buffer);
bool ssl_is_key_type_supported(int key_type);
// ssl_compare_public_and_private_key returns true if `pubkey` is the public
// counterpart to `privkey`. Otherwise it returns false and pushes a helpful
// message on the error queue.
bool ssl_compare_public_and_private_key(const EVP_PKEY *pubkey,
const EVP_PKEY *privkey);
bool ssl_get_new_session(SSL_HANDSHAKE *hs);
// ssl_encrypt_ticket encrypt a ticket for `session` and writes the result to
// `out`. It returns true on success and false on error. If, on success, nothing
// was written to `out`, the caller should skip sending a ticket.
bool ssl_encrypt_ticket(SSL_HANDSHAKE *hs, CBB *out,
const SSL_SESSION *session);
bool ssl_ctx_rotate_ticket_encryption_key(SSLContext *ctx);
// ssl_session_new returns a newly-allocated blank `SSL_SESSION` or nullptr on
// error.
UniquePtr<SSL_SESSION> ssl_session_new(const SSL_X509_METHOD *x509_method);
// ssl_hash_session_id returns a hash of `session_id`, suitable for a hash table
// keyed on session IDs.
uint32_t ssl_hash_session_id(Span<const uint8_t> session_id);
// SSL_SESSION_parse parses an `SSL_SESSION` from `cbs` and advances `cbs` over
// the parsed data.
OPENSSL_EXPORT UniquePtr<SSL_SESSION> SSL_SESSION_parse(
CBS *cbs, const SSL_X509_METHOD *x509_method, CRYPTO_BUFFER_POOL *pool);
// ssl_session_serialize writes `in` to `cbb` as if it were serialising a
// session for Session-ID resumption. It returns true on success and false on
// error.
OPENSSL_EXPORT bool ssl_session_serialize(const SSL_SESSION *in, CBB *cbb);
enum class SSLSessionType {
// The session is not resumable.
kNotResumable,
// The session uses a TLS 1.2 session ID.
kID,
// The session uses a TLS 1.2 ticket.
kTicket,
// The session uses a TLS 1.3 pre-shared key.
kPreSharedKey,
};
// ssl_session_get_type returns the type of `session`.
SSLSessionType ssl_session_get_type(const SSL_SESSION *session);
// ssl_session_is_context_valid returns whether `session`'s session ID context
// matches the one set on `hs`.
bool ssl_session_is_context_valid(const SSL_HANDSHAKE *hs,
const SSL_SESSION *session);
// ssl_session_is_time_valid returns true if `session` is still valid and false
// if it has expired.
bool ssl_session_is_time_valid(const SSL *ssl, const SSL_SESSION *session);
// ssl_session_is_resumable returns whether `session` is resumable for `hs`.
bool ssl_session_is_resumable(const SSL_HANDSHAKE *hs,
const SSL_SESSION *session);
// ssl_session_protocol_version returns the protocol version associated with
// `session`. Note that despite the name, this is not the same as
// `SSL_SESSION_get_protocol_version`. The latter is based on upstream's name.
uint16_t ssl_session_protocol_version(const SSL_SESSION *session);
// ssl_session_get_digest returns the digest used in `session`.
const EVP_MD *ssl_session_get_digest(const SSL_SESSION *session);
// ssl_session_has_peer_cred returns whether `session` contains the peer's
// (non-PSK) credentials (either X.509 cert chain or raw public key, depending
// on the peer's certificate type) or a valid SHA-256 hash thereof.
bool ssl_session_has_peer_cred(const SSL_SESSION *session);
void ssl_set_session(SSL *ssl, SSL_SESSION *session);
// ssl_get_prev_session looks up the previous session based on `client_hello`.
// On success, it sets `*out_session` to the session or nullptr if none was
// found. If the session could not be looked up synchronously, it returns
// `ssl_hs_pending_session` and should be called again. If a ticket could not be
// decrypted immediately it returns `ssl_hs_pending_ticket` and should also
// be called again. Otherwise, it returns `ssl_hs_error`.
enum ssl_hs_wait_t ssl_get_prev_session(SSL_HANDSHAKE *hs,
UniquePtr<SSL_SESSION> *out_session,
bool *out_tickets_supported,
bool *out_renew_ticket,
const SSL_CLIENT_HELLO *client_hello);
// The following flags determine which parts of the session are duplicated.
#define SSL_SESSION_DUP_AUTH_ONLY 0x0
#define SSL_SESSION_INCLUDE_TICKET 0x1
#define SSL_SESSION_INCLUDE_NONAUTH 0x2
#define SSL_SESSION_DUP_ALL \
(SSL_SESSION_INCLUDE_TICKET | SSL_SESSION_INCLUDE_NONAUTH)
// SSL_SESSION_dup returns a newly-allocated `SSL_SESSION` with a copy of the
// fields in `session` or nullptr on error. The new session is non-resumable and
// must be explicitly marked resumable once it has been filled in.
OPENSSL_EXPORT UniquePtr<SSL_SESSION> SSL_SESSION_dup(
const SSL_SESSION *session, int dup_flags);
// ssl_session_rebase_time updates `session`'s start time to the current time,
// adjusting the timeout so the expiration time is unchanged.
void ssl_session_rebase_time(SSL *ssl, SSL_SESSION *session);
// ssl_session_renew_timeout calls `ssl_session_rebase_time` and renews
// `session`'s timeout to `timeout` (measured from the current time). The
// renewal is clamped to the session's auth_timeout.
void ssl_session_renew_timeout(SSL *ssl, SSL_SESSION *session,
uint32_t timeout);
void ssl_update_cache(SSL *ssl);
void ssl_send_alert(SSL *ssl, int level, int desc);
int ssl_send_alert_impl(SSL *ssl, int level, int desc);
bool tls_get_message(const SSL *ssl, SSLMessage *out);
ssl_open_record_t tls_open_handshake(SSL *ssl, size_t *out_consumed,
uint8_t *out_alert, Span<uint8_t> in);
void tls_next_message(SSL *ssl);
int tls_dispatch_alert(SSL *ssl);
ssl_open_record_t tls_open_app_data(SSL *ssl, Span<uint8_t> *out,
size_t *out_consumed, uint8_t *out_alert,
Span<uint8_t> in);
ssl_open_record_t tls_open_change_cipher_spec(SSL *ssl, size_t *out_consumed,
uint8_t *out_alert,
Span<uint8_t> in);
int tls_write_app_data(SSL *ssl, bool *out_needs_handshake,
size_t *out_bytes_written, Span<const uint8_t> in);
bool tls_new(SSL *ssl);
void tls_free(SSL *ssl);
bool tls_init_message(const SSL *ssl, CBB *cbb, CBB *body, uint8_t type);
bool tls_finish_message(const SSL *ssl, CBB *cbb, Array<uint8_t> *out_msg);
bool tls_add_message(SSL *ssl, Array<uint8_t> msg);
bool tls_add_change_cipher_spec(SSL *ssl);
int tls_flush(SSL *ssl);
bool dtls1_init_message(const SSL *ssl, CBB *cbb, CBB *body, uint8_t type);
bool dtls1_finish_message(const SSL *ssl, CBB *cbb, Array<uint8_t> *out_msg);
bool dtls1_add_message(SSL *ssl, Array<uint8_t> msg);
bool dtls1_add_change_cipher_spec(SSL *ssl);
void dtls1_finish_flight(SSL *ssl);
void dtls1_schedule_ack(SSL *ssl);
int dtls1_flush(SSL *ssl);
// ssl_add_message_cbb finishes the handshake message in `cbb` and adds it to
// the pending flight. It returns true on success and false on error.
bool ssl_add_message_cbb(SSL *ssl, CBB *cbb);
// ssl_hash_message incorporates `msg` into the handshake hash. It returns true
// on success and false on allocation failure.
bool ssl_hash_message(SSL_HANDSHAKE *hs, const SSLMessage &msg);
ssl_open_record_t dtls1_process_ack(SSL *ssl, uint8_t *out_alert,
DTLSRecordNumber ack_record_number,
Span<const uint8_t> data);
ssl_open_record_t dtls1_open_app_data(SSL *ssl, Span<uint8_t> *out,
size_t *out_consumed, uint8_t *out_alert,
Span<uint8_t> in);
ssl_open_record_t dtls1_open_change_cipher_spec(SSL *ssl, size_t *out_consumed,
uint8_t *out_alert,
Span<uint8_t> in);
int dtls1_write_app_data(SSL *ssl, bool *out_needs_handshake,
size_t *out_bytes_written, Span<const uint8_t> in);
// dtls1_write_record sends a record. It returns one on success and <= 0 on
// error.
int dtls1_write_record(SSL *ssl, int type, Span<const uint8_t> in,
uint16_t epoch);
bool dtls1_parse_fragment(CBS *cbs, struct hm_header_st *out_hdr,
CBS *out_body);
// DTLS1_MTU_TIMEOUTS is the maximum number of retransmit timeouts to expire
// before starting to decrease the MTU.
#define DTLS1_MTU_TIMEOUTS 2
// DTLS1_MAX_TIMEOUTS is the maximum number of retransmit timeouts to expire
// before failing the DTLS handshake.
#define DTLS1_MAX_TIMEOUTS 12
void dtls1_stop_timer(SSL *ssl);
unsigned int dtls1_min_mtu();
bool dtls1_new(SSL *ssl);
void dtls1_free(SSL *ssl);
bool dtls1_process_handshake_fragments(SSL *ssl, uint8_t *out_alert,
DTLSRecordNumber record_number,
Span<const uint8_t> record);
bool dtls1_get_message(const SSL *ssl, SSLMessage *out);
ssl_open_record_t dtls1_open_handshake(SSL *ssl, size_t *out_consumed,
uint8_t *out_alert, Span<uint8_t> in);
void dtls1_next_message(SSL *ssl);
int dtls1_dispatch_alert(SSL *ssl);
// tls1_configure_aead configures either the read or write direction AEAD (as
// determined by `direction`) using the keys generated by the TLS KDF. The
// `key_block_cache` argument is used to store the generated key block, if
// empty. Otherwise it's assumed that the key block is already contained within
// it. It returns true on success or false on error.
bool tls1_configure_aead(SSL *ssl, evp_aead_direction_t direction,
Array<uint8_t> *key_block_cache,
const SSL_SESSION *session,
Span<const uint8_t> iv_override);
bool tls1_change_cipher_state(SSL_HANDSHAKE *hs,
evp_aead_direction_t direction);
// tls1_generate_master_secret computes the master secret from `premaster` and
// writes it to `out`. `out` must have size `SSL3_MASTER_SECRET_SIZE`.
bool tls1_generate_master_secret(SSL_HANDSHAKE *hs, Span<uint8_t> out,
Span<const uint8_t> premaster);
// tls1_check_group_id returns whether `group_id` is consistent with locally-
// configured group preferences.
bool tls1_check_group_id(const SSL_HANDSHAKE *ssl, uint16_t group_id);
// tls1_get_shared_group sets `*out_group_id` to the first preferred shared
// group between client and server preferences and returns true. If none may be
// found, it returns false.
bool tls1_get_shared_group(SSL_HANDSHAKE *hs, uint16_t *out_group_id);
// ssl_add_clienthello_tlsext writes ClientHello extensions to `out` for `type`.
// It returns true on success and false on failure. `out` must currently contain
// a ClientHello message, not including the message and record header. (Its
// contents will be used to compute padding and PSK binders.)
//
// If `type` is `ssl_client_hello_inner`, this function also writes the
// compressed extensions to `out_encoded`. Otherwise, `out_encoded` should be
// nullptr.
bool ssl_add_clienthello_tlsext(SSL_HANDSHAKE *hs, CBB *out, CBB *out_encoded,
ssl_client_hello_type_t type);
bool ssl_add_serverhello_tlsext(SSL_HANDSHAKE *hs, CBB *out);
bool ssl_parse_clienthello_tlsext(SSL_HANDSHAKE *hs,
const SSL_CLIENT_HELLO *client_hello);
bool ssl_parse_serverhello_tlsext(SSL_HANDSHAKE *hs, const CBS *extensions);
#define tlsext_tick_md EVP_sha256
// ssl_process_ticket processes a session ticket from the client. It returns
// one of:
// `ssl_ticket_aead_success`: `*out_session` is set to the parsed session and
// `*out_renew_ticket` is set to whether the ticket should be renewed.
// `ssl_ticket_aead_ignore_ticket`: `*out_renew_ticket` is set to whether a
// fresh ticket should be sent, but the given ticket cannot be used.
// `ssl_ticket_aead_retry`: the ticket could not be immediately decrypted.
// Retry later.
// `ssl_ticket_aead_error`: an error occurred that is fatal to the connection.
//
// If `save_ticket` is true, `*out_session` will have a copy of the ticket saved
// in its `ticket` field.
enum ssl_ticket_aead_result_t ssl_process_ticket(
SSL_HANDSHAKE *hs, UniquePtr<SSL_SESSION> *out_session,
bool *out_renew_ticket, Span<const uint8_t> ticket,
Span<const uint8_t> session_id, bool save_ticket);
// tls1_verify_channel_id processes `msg` as a Channel ID message, and verifies
// the signature. If the key is valid, it saves the Channel ID and returns true.
// Otherwise, it returns false.
bool tls1_verify_channel_id(SSL_HANDSHAKE *hs, const SSLMessage &msg);
// tls1_write_channel_id generates a Channel ID message and puts the output in
// `cbb`. `ssl->channel_id_private` must already be set before calling. This
// function returns true on success and false on error.
bool tls1_write_channel_id(SSL_HANDSHAKE *hs, CBB *cbb);
// tls1_channel_id_hash computes the hash to be signed by Channel ID and writes
// it to `out`, which must contain at least `EVP_MAX_MD_SIZE` bytes. It returns
// true on success and false on failure.
bool tls1_channel_id_hash(SSL_HANDSHAKE *hs, uint8_t *out, size_t *out_len);
// tls1_record_handshake_hashes_for_channel_id records the current handshake
// hashes in `hs->new_session` so that Channel ID resumptions can sign that
// data.
bool tls1_record_handshake_hashes_for_channel_id(SSL_HANDSHAKE *hs);
// ssl_can_write returns whether `ssl` is allowed to write.
bool ssl_can_write(const SSL *ssl);
// ssl_can_read returns whether `ssl` is allowed to read.
bool ssl_can_read(const SSL *ssl);
OPENSSL_timeval ssl_ctx_get_current_time(const SSLContext *ctx);
// ssl_reset_error_state resets state for `SSL_get_error`.
void ssl_reset_error_state(SSL *ssl);
// ssl_set_read_error sets `ssl`'s read half into an error state, saving the
// current state of the error queue.
void ssl_set_read_error(SSL *ssl);
BSSL_NAMESPACE_END
// Opaque C types.
//
// The following types are exported to C code as public typedefs, so they must
// be defined outside of the namespace.
//
// TODO(crbug.com/500444613): Move these to the bssl namespace.
// ssl_method_st backs the public `SSL_METHOD` type. It is a compatibility
// structure to support the legacy version-locked methods.
struct ssl_method_st {
// version, if non-zero, is the only protocol version acceptable to an
// SSL_CTX initialized from this method.
uint16_t version;
// method is the underlying SSL_PROTOCOL_METHOD that initializes the
// SSL_CTX.
const bssl::SSL_PROTOCOL_METHOD *method;
// x509_method contains pointers to functions that might deal with `X509`
// compatibility, or might be a no-op, depending on the application.
const bssl::SSL_X509_METHOD *x509_method;
};
BSSL_NAMESPACE_BEGIN
class SSLContext : public ssl_ctx_st, public RefCounted<SSLContext> {
public:
explicit SSLContext(const SSL_METHOD *ssl_method);
SSLContext(const SSLContext &) = delete;
SSLContext &operator=(const SSLContext &) = delete;
const SSL_PROTOCOL_METHOD *method = nullptr;
const SSL_X509_METHOD *x509_method = nullptr;
// lock is used to protect various operations on this object.
mutable Mutex lock;
// conf_max_version is the maximum acceptable protocol version configured by
// `SSL_CTX_set_max_proto_version`. Note this version is normalized in DTLS
// and is further constrained by `SSL_OP_NO_*`.
uint16_t conf_max_version = 0;
// conf_min_version is the minimum acceptable protocol version configured by
// `SSL_CTX_set_min_proto_version`. Note this version is normalized in DTLS
// and is further constrained by `SSL_OP_NO_*`.
uint16_t conf_min_version = 0;
// num_tickets is the number of tickets to send immediately after the TLS 1.3
// handshake. TLS 1.3 recommends single-use tickets so, by default, issue two
/// in case the client makes several connections before getting a renewal.
uint8_t num_tickets = 2;
// quic_method is the method table corresponding to the QUIC hooks.
const SSL_QUIC_METHOD *quic_method = nullptr;
UniquePtr<SSLCipherPreferenceList> cipher_list;
X509_STORE *cert_store = nullptr;
LHASH_OF(SSL_SESSION) *sessions = nullptr;
// Most session-ids that will be cached, default is
// SSL_SESSION_CACHE_MAX_SIZE_DEFAULT. 0 is unlimited.
unsigned long session_cache_size = SSL_SESSION_CACHE_MAX_SIZE_DEFAULT;
SSL_SESSION *session_cache_head = nullptr;
SSL_SESSION *session_cache_tail = nullptr;
// handshakes_since_cache_flush is the number of successful handshakes since
// the last cache flush.
int handshakes_since_cache_flush = 0;
// This can have one of 2 values, ored together,
// SSL_SESS_CACHE_CLIENT,
// SSL_SESS_CACHE_SERVER,
// Default is SSL_SESSION_CACHE_SERVER, which means only
// SSL_accept which cache SSL_SESSIONS.
int session_cache_mode = SSL_SESS_CACHE_SERVER;
// session_timeout is the default lifetime for new sessions in TLS 1.2 and
// earlier, in seconds.
uint32_t session_timeout = SSL_DEFAULT_SESSION_TIMEOUT;
// session_psk_dhe_timeout is the default lifetime for new sessions in TLS
// 1.3, in seconds.
uint32_t session_psk_dhe_timeout = SSL_DEFAULT_SESSION_PSK_DHE_TIMEOUT;
// If this callback is not null, it will be called each time a session id is
// added to the cache. If this function returns 1, it means that the
// callback will do a SSL_SESSION_free() when it has finished using it.
// Otherwise, on 0, it means the callback has finished with it. If
// remove_session_cb is not null, it will be called when a session-id is
// removed from the cache. After the call, OpenSSL will SSL_SESSION_free()
// it.
int (*new_session_cb)(SSL *ssl, SSL_SESSION *sess) = nullptr;
void (*remove_session_cb)(SSL_CTX *ctx, SSL_SESSION *sess) = nullptr;
SSL_SESSION *(*get_session_cb)(SSL *ssl, const uint8_t *data, int len,
int *copy) = nullptr;
// if defined, these override the X509_verify_cert() calls
int (*app_verify_callback)(X509_STORE_CTX *store_ctx, void *arg) = nullptr;
void *app_verify_arg = nullptr;
ssl_verify_result_t (*custom_verify_callback)(SSL *ssl,
uint8_t *out_alert) = nullptr;
// Default password callback.
pem_password_cb *default_passwd_callback = nullptr;
// Default password callback user data.
void *default_passwd_callback_userdata = nullptr;
// get client cert callback
int (*client_cert_cb)(SSL *ssl, X509 **out_x509,
EVP_PKEY **out_pkey) = nullptr;
CRYPTO_EX_DATA ex_data;
// Default values used when no per-SSL value is defined follow
void (*info_callback)(const SSL *ssl, int type, int value) = nullptr;
// what we put in client cert requests
UniquePtr<STACK_OF(CRYPTO_BUFFER)> client_CA;
// cached_x509_client_CA is a cache of parsed versions of the elements of
// `client_CA`.
STACK_OF(X509_NAME) *cached_x509_client_CA = nullptr;
// What we put in client hello in the CA extension.
UniquePtr<STACK_OF(CRYPTO_BUFFER)> CA_names;
// What we request in the trust_anchors extension.
std::optional<Array<uint8_t>> requested_trust_anchors;
// Default values to use in SSL structures follow (these are copied by
// SSL_new)
uint32_t options = SSL_OP_ALL;
// Disable the auto-chaining feature by default. wpa_supplicant relies on this
// feature, but require callers opt into it.
uint32_t mode = SSL_MODE_NO_AUTO_CHAIN;
uint32_t max_cert_list = SSL_MAX_CERT_LIST_DEFAULT;
UniquePtr<CERT> cert;
// callback that allows applications to peek at protocol messages
void (*msg_callback)(int is_write, int version, int content_type,
const void *buf, size_t len, SSL *ssl,
void *arg) = nullptr;
void *msg_callback_arg = nullptr;
int verify_mode = SSL_VERIFY_NONE;
int (*default_verify_callback)(int ok, X509_STORE_CTX *ctx) =
nullptr; // called 'verify_callback' in the SSL
X509_VERIFY_PARAM *param = nullptr;
// select_certificate_cb is called before most ClientHello processing and
// before the decision whether to resume a session is made. See
// `ssl_select_cert_result_t` for details of the return values.
ssl_select_cert_result_t (*select_certificate_cb)(const SSL_CLIENT_HELLO *) =
nullptr;
// dos_protection_cb is called once the resumption decision for a ClientHello
// has been made. It returns one to continue the handshake or zero to
// abort.
int (*dos_protection_cb)(const SSL_CLIENT_HELLO *) = nullptr;
// Controls whether to verify certificates when resuming connections. They
// were already verified when the connection was first made, so the default is
// false. For now, this is only respected on clients, not servers.
bool reverify_on_resume = false;
// Maximum amount of data to send in one fragment. actual record size can be
// more than this due to padding and MAC overheads.
uint16_t max_send_fragment = SSL3_RT_MAX_PLAIN_LENGTH;
// TLS extensions servername callback
int (*servername_callback)(SSL *, int *, void *) = nullptr;
void *servername_arg = nullptr;
// RFC 4507 session ticket keys. `ticket_key_current` may be NULL before the
// first handshake and `ticket_key_prev` may be NULL at any time.
// Automatically generated ticket keys are rotated as needed at handshake
// time. Hence, all access must be synchronized through `lock`.
UniquePtr<TicketKey> ticket_key_current;
UniquePtr<TicketKey> ticket_key_prev;
// Callback to support customisation of ticket key setting
int (*ticket_key_cb)(SSL *ssl, uint8_t *name, uint8_t *iv,
EVP_CIPHER_CTX *ectx, HMAC_CTX *hctx, int enc) = nullptr;
// Server-only: psk_identity_hint is the default identity hint to send in
// PSK-based key exchanges.
UniquePtr<char> psk_identity_hint;
unsigned (*psk_client_callback)(SSL *ssl, const char *hint, char *identity,
unsigned max_identity_len, uint8_t *psk,
unsigned max_psk_len) = nullptr;
unsigned (*psk_server_callback)(SSL *ssl, const char *identity, uint8_t *psk,
unsigned max_psk_len) = nullptr;
// Next protocol negotiation information
// (for experimental NPN extension).
// For a server, this contains a callback function by which the set of
// advertised protocols can be provided.
int (*next_protos_advertised_cb)(SSL *ssl, const uint8_t **out,
unsigned *out_len, void *arg) = nullptr;
void *next_protos_advertised_cb_arg = nullptr;
// For a client, this contains a callback function that selects the
// next protocol from the list provided by the server.
int (*next_proto_select_cb)(SSL *ssl, uint8_t **out, uint8_t *out_len,
const uint8_t *in, unsigned in_len,
void *arg) = nullptr;
void *next_proto_select_cb_arg = nullptr;
// ALPN information
// (we are in the process of transitioning from NPN to ALPN.)
// For a server, this contains a callback function that allows the
// server to select the protocol for the connection.
// out: on successful return, this must point to the raw protocol
// name (without the length prefix).
// outlen: on successful return, this contains the length of `*out`.
// in: points to the client's list of supported protocols in
// wire-format.
// inlen: the length of `in`.
int (*alpn_select_cb)(SSL *ssl, const uint8_t **out, uint8_t *out_len,
const uint8_t *in, unsigned in_len,
void *arg) = nullptr;
void *alpn_select_cb_arg = nullptr;
// For a client, this contains the list of supported protocols in wire
// format.
Array<uint8_t> alpn_client_proto_list;
// SRTP profiles we are willing to do from RFC 5764
UniquePtr<STACK_OF(SRTP_PROTECTION_PROFILE)> srtp_profiles;
// Defined compression algorithms for certificates.
Vector<CertCompressionAlg> cert_compression_algs;
// Supported group values and flags inherited by SSL structure
Array<uint16_t> supported_group_list;
Array<uint32_t> supported_group_list_flags;
// channel_id_private is the client's Channel ID private key, or null if
// Channel ID should not be offered on this connection.
UniquePtr<EVP_PKEY> channel_id_private;
// ech_keys contains the server's list of ECHConfig values and associated
// private keys. This list may be swapped out at any time, so all access must
// be synchronized through `lock`.
UniquePtr<SSLECHKeys> ech_keys;
// keylog_callback, if not NULL, is the key logging callback. See
// `SSL_CTX_set_keylog_callback`.
void (*keylog_callback)(const SSL *ssl, const char *line) = nullptr;
// current_time_cb, if not NULL, is the function to use to get the current
// time. It sets `*out_clock` to the current time. The `ssl` argument is
// always NULL. See `SSL_CTX_set_current_time_cb`.
void (*current_time_cb)(const SSL *ssl, struct timeval *out_clock) = nullptr;
// pool is used for all `CRYPTO_BUFFER`s in case we wish to share certificate
// memory.
UniquePtr<CRYPTO_BUFFER_POOL> pool;
// ticket_aead_method contains function pointers for opening and sealing
// session tickets.
const SSL_TICKET_AEAD_METHOD *ticket_aead_method = nullptr;
// legacy_ocsp_callback implements an OCSP-related callback for OpenSSL
// compatibility.
int (*legacy_ocsp_callback)(SSL *ssl, void *arg) = nullptr;
void *legacy_ocsp_callback_arg = nullptr;
// compliance_policy limits the set of ciphers that can be selected when
// negotiating a TLS 1.3 connection.
enum ssl_compliance_policy_t compliance_policy = ssl_compliance_policy_none;
// verify_sigalgs, if not empty, is the set of signature algorithms
// accepted from the peer in decreasing order of preference.
Array<uint16_t> verify_sigalgs;
// accepted_peer_cert_types inherited by SSL struct.
InplaceVector<uint8_t, kNumCertTypes> accepted_peer_cert_types;
// available_client_cert_types inherited by SSL struct.
InplaceVector<uint8_t, kNumCertTypes> available_client_cert_types;
// retain_only_sha256_of_client_certs is true if we should compute the SHA256
// hash of the peer's certificate and then discard it to save memory and
// session space. Only effective on the server side.
bool retain_only_sha256_of_client_certs : 1;
// quiet_shutdown is true if the connection should not send a close_notify on
// shutdown.
bool quiet_shutdown : 1;
// ocsp_stapling_enabled is only used by client connections and indicates
// whether OCSP stapling will be requested.
bool ocsp_stapling_enabled : 1;
// If true, a client will request certificate timestamps.
bool signed_cert_timestamps_enabled : 1;
// channel_id_enabled is whether Channel ID is enabled. For a server, means
// that we'll accept Channel IDs from clients. For a client, means that we'll
// advertise support.
bool channel_id_enabled : 1;
// grease_enabled is whether GREASE (RFC 8701) is enabled.
bool grease_enabled : 1;
// permute_extensions is whether to permute extensions when sending messages.
bool permute_extensions : 1;
// allow_unknown_alpn_protos is whether the client allows unsolicited ALPN
// protocols from the peer.
bool allow_unknown_alpn_protos : 1;
// false_start_allowed_without_alpn is whether False Start (if
// `SSL_MODE_ENABLE_FALSE_START` is enabled) is allowed without ALPN.
bool false_start_allowed_without_alpn : 1;
// handoff indicates that a server should stop after receiving the
// ClientHello and pause the handshake in such a way that `SSL_get_error`
// returns `SSL_ERROR_HANDOFF`.
bool handoff : 1;
// If enable_early_data is true, early data can be sent and accepted.
bool enable_early_data : 1;
// aes_hw_override if set indicates we should override checking for AES
// hardware support, and use the value in aes_hw_override_value instead.
bool aes_hw_override : 1;
// aes_hw_override_value is used for testing to indicate the support or lack
// of support for AES hardware. The value is only considered if
// `aes_hw_override` is true.
bool aes_hw_override_value : 1;
// resumption_across_names_enabled indicates whether a TLS 1.3 server should
// signal its sessions may be resumed across names in the server certificate.
bool resumption_across_names_enabled : 1;
private:
friend RefCounted;
~SSLContext();
};
BSSL_NAMESPACE_END
struct ssl_st {
explicit ssl_st(bssl::SSLContext *ctx_arg);
ssl_st(const ssl_st &) = delete;
ssl_st &operator=(const ssl_st &) = delete;
~ssl_st();
// method is the method table corresponding to the current protocol (DTLS or
// TLS).
const bssl::SSL_PROTOCOL_METHOD *method = nullptr;
// config is a container for handshake configuration. Accesses to this field
// should check for nullptr, since configuration may be shed after the
// handshake completes. (If you have the `SSL_HANDSHAKE` object at hand, use
// that instead, and skip the null check.)
bssl::UniquePtr<bssl::SSL_CONFIG> config;
uint16_t max_send_fragment = 0;
// There are 2 BIO's even though they are normally both the same. This is so
// data can be read and written to different handlers
bssl::UniquePtr<BIO> rbio; // used by SSL_read
bssl::UniquePtr<BIO> wbio; // used by SSL_write
// do_handshake runs the handshake. On completion, it returns `ssl_hs_ok`.
// Otherwise, it returns a value corresponding to what operation is needed to
// progress.
bssl::ssl_hs_wait_t (*do_handshake)(bssl::SSL_HANDSHAKE *hs) = nullptr;
bssl::SSL3_STATE *s3 = nullptr; // TLS variables
bssl::DTLS1_STATE *d1 = nullptr; // DTLS variables
// callback that allows applications to peek at protocol messages
void (*msg_callback)(int write_p, int version, int content_type,
const void *buf, size_t len, SSL *ssl,
void *arg) = nullptr;
void *msg_callback_arg = nullptr;
// session info
// initial_timeout_duration_ms is the default DTLS timeout duration in
// milliseconds. It's used to initialize the timer any time it's restarted. We
// default to RFC 9147's recommendation for real-time applications, 400ms.
uint32_t initial_timeout_duration_ms = 400;
// session is the configured session to be offered by the client. This session
// is immutable.
bssl::UniquePtr<SSL_SESSION> session;
void (*info_callback)(const SSL *ssl, int type, int value) = nullptr;
bssl::UniquePtr<bssl::SSLContext> ctx;
// session_ctx is the `SSLContext` used for the session cache and related
// settings.
bssl::UniquePtr<bssl::SSLContext> session_ctx;
// extra application data
CRYPTO_EX_DATA ex_data;
uint32_t options = 0; // protocol behaviour
uint32_t mode = 0; // API behaviour
uint32_t max_cert_list = 0;
bssl::UniquePtr<char> hostname;
// quic_method is the method table corresponding to the QUIC hooks.
const SSL_QUIC_METHOD *quic_method = nullptr;
// renegotiate_mode controls how peer renegotiation attempts are handled.
ssl_renegotiate_mode_t renegotiate_mode = ssl_renegotiate_never;
// server is true iff the this SSL* is the server half. Note: before the SSL*
// is initialized by either SSL_set_accept_state or SSL_set_connect_state,
// the side is not determined. In this state, server is always false.
bool server : 1;
// quiet_shutdown is true if the connection should not send a close_notify on
// shutdown.
bool quiet_shutdown : 1;
// If enable_early_data is true, early data can be sent and accepted.
bool enable_early_data : 1;
// resumption_across_names_enabled indicates whether a TLS 1.3 server should
// signal its sessions may be resumed across names in the server certificate.
bool resumption_across_names_enabled : 1;
};
struct ssl_session_st : public bssl::RefCounted<ssl_session_st> {
explicit ssl_session_st(const bssl::SSL_X509_METHOD *method);
ssl_session_st(const ssl_session_st &) = delete;
ssl_session_st &operator=(const ssl_session_st &) = delete;
// ssl_version is the (D)TLS version that established the session.
uint16_t ssl_version = 0;
// group_id is the ID of the ECDH group used to establish this session or zero
// if not applicable or unknown.
uint16_t group_id = 0;
// peer_signature_algorithm is the signature algorithm used to authenticate
// the peer, or zero if not applicable or unknown.
uint16_t peer_signature_algorithm = 0;
// secret, in TLS 1.2 and below, is the master secret associated with the
// session. In TLS 1.3 and up, it is the resumption PSK for sessions handed to
// the caller, but it stores the resumption secret when stored on `SSL`
// objects.
bssl::InplaceVector<uint8_t, SSL_MAX_MASTER_KEY_LENGTH> secret;
bssl::InplaceVector<uint8_t, SSL_MAX_SSL_SESSION_ID_LENGTH> session_id;
// this is used to determine whether the session is being reused in
// the appropriate context. It is up to the application to set this,
// via SSL_new
bssl::InplaceVector<uint8_t, SSL_MAX_SID_CTX_LENGTH> sid_ctx;
bssl::UniquePtr<char> psk_identity;
// certs contains the certificate chain from the peer, starting with the leaf
// certificate. This must be null if `peer_raw_public_key` is non-null.
bssl::UniquePtr<STACK_OF(CRYPTO_BUFFER)> certs;
const bssl::SSL_X509_METHOD *x509_method = nullptr;
// x509_peer is the peer's certificate. This must be null if
// `peer_raw_public_key` is non-null.
X509 *x509_peer = nullptr;
// x509_chain is the certificate chain sent by the peer. NOTE: for historical
// reasons, when a client (so the peer is a server), the chain includes
// `peer`, but when a server it does not. This must be null if
// `peer_raw_public_key` is non-null.
STACK_OF(X509) *x509_chain = nullptr;
// x509_chain_without_leaf is a lazily constructed copy of `x509_chain` that
// omits the leaf certificate. This exists because OpenSSL, historically,
// didn't include the leaf certificate in the chain for a server, but did for
// a client. The `x509_chain` always includes it and, if an API call requires
// a chain without, it is stored here. This must be null if
// `peer_raw_public_key` is non-null.
STACK_OF(X509) *x509_chain_without_leaf = nullptr;
// verify_result is the result of certificate verification in the case of
// non-fatal certificate errors.
long verify_result = X509_V_ERR_INVALID_CALL;
// timeout is the lifetime of the session in seconds, measured from `time`.
// This is renewable up to `auth_timeout`.
uint32_t timeout = SSL_DEFAULT_SESSION_TIMEOUT;
// auth_timeout is the non-renewable lifetime of the session in seconds,
// measured from `time`.
uint32_t auth_timeout = SSL_DEFAULT_SESSION_TIMEOUT;
// time is the time the session was issued, measured in seconds from the UNIX
// epoch.
uint64_t time = 0;
const SSL_CIPHER *cipher = nullptr;
CRYPTO_EX_DATA ex_data; // application specific data
// These are used to make removal of session-ids more efficient and to
// implement a maximum cache size.
SSL_SESSION *prev = nullptr, *next = nullptr;
bssl::Array<uint8_t> ticket;
bssl::UniquePtr<CRYPTO_BUFFER> signed_cert_timestamp_list;
// The OCSP response that came with the session.
bssl::UniquePtr<CRYPTO_BUFFER> ocsp_response;
// peer_sha256 contains the SHA-256 hash of the peer's X.509 certificate or
// raw public key if `peer_sha256_valid` is true. (`peer_cert_type` indicates
// which type of credential is hashed here.)
uint8_t peer_sha256[SHA256_DIGEST_LENGTH] = {0};
// original_handshake_hash contains the handshake hash (either SHA-1+MD5 or
// SHA-2, depending on TLS version) for the original, full handshake that
// created a session. This is used by Channel IDs during resumption.
bssl::InplaceVector<uint8_t, SSL_MAX_MD_SIZE> original_handshake_hash;
uint32_t ticket_lifetime_hint = 0; // Session lifetime hint in seconds
uint32_t ticket_age_add = 0;
// ticket_max_early_data is the maximum amount of data allowed to be sent as
// early data. If zero, 0-RTT is disallowed.
uint32_t ticket_max_early_data = 0;
// early_alpn is the ALPN protocol from the initial handshake. This is only
// stored for TLS 1.3 and above in order to enforce ALPN matching for 0-RTT
// resumptions. For the current connection's ALPN protocol, see
// `alpn_selected` on `SSL3_STATE`.
bssl::Array<uint8_t> early_alpn;
// local_application_settings, if `has_application_settings` is true, is the
// local ALPS value for this connection.
bssl::Array<uint8_t> local_application_settings;
// peer_application_settings, if `has_application_settings` is true, is the
// peer ALPS value for this connection.
bssl::Array<uint8_t> peer_application_settings;
// extended_master_secret is whether the master secret in this session was
// generated using EMS and thus isn't vulnerable to the Triple Handshake
// attack.
bool extended_master_secret : 1;
// peer_sha256_valid is whether `peer_sha256` is valid.
bool peer_sha256_valid : 1; // Non-zero if peer_sha256 is valid
// not_resumable is used to indicate that session resumption is disallowed.
bool not_resumable : 1;
// ticket_age_add_valid is whether `ticket_age_add` is valid.
bool ticket_age_add_valid : 1;
// is_server is whether this session was created by a server.
bool is_server : 1;
// is_quic indicates whether this session was created using QUIC.
bool is_quic : 1;
// has_application_settings indicates whether ALPS was negotiated in this
// session.
bool has_application_settings : 1;
// is_resumable_across_names indicates whether the session may be resumed for
// any of the identities presented in the certificate.
bool is_resumable_across_names : 1;
// quic_early_data_context is used to determine whether early data must be
// rejected when performing a QUIC handshake.
bssl::Array<uint8_t> quic_early_data_context;
// peer_cert_type is the peer's cert type (`TLSEXT_cert_type_*` value), which
// determines the type of Certificate the peer used for this session: which of
// `certs` xor `peer_raw_public_key` is populated for an authenticated
// session.
uint8_t peer_cert_type = bssl::kDefaultCertType;
// peer_raw_public_key, if non-null, is the raw public key received from the
// peer. This must be null if `certs` is non-null.
bssl::UniquePtr<EVP_PKEY> peer_raw_public_key;
private:
friend RefCounted;
~ssl_session_st();
};
#endif // OPENSSL_HEADER_SSL_INTERNAL_H