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boringssl/ssl/internal.h
Steven Valdez cd8470f7fa Adding support for draft 21 as a TLS 1.3 variant. 
Change-Id: I46686aea9b68105cfe70a11db0e88052781e179c
Reviewed-on: https://boringssl-review.googlesource.com/22164
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Reviewed-by: David Benjamin <davidben@google.com>
Reviewed-by: Steven Valdez <svaldez@google.com>
2017-11-01 21:32:36 +00:00

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/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
/* ====================================================================
* Copyright (c) 1998-2007 The OpenSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* openssl-core@openssl.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com).
*
*/
/* ====================================================================
* Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
* ECC cipher suite support in OpenSSL originally developed by
* SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
*/
/* ====================================================================
* Copyright 2005 Nokia. All rights reserved.
*
* The portions of the attached software ("Contribution") is developed by
* Nokia Corporation and is licensed pursuant to the OpenSSL open source
* license.
*
* The Contribution, originally written by Mika Kousa and Pasi Eronen of
* Nokia Corporation, consists of the "PSK" (Pre-Shared Key) ciphersuites
* support (see RFC 4279) to OpenSSL.
*
* No patent licenses or other rights except those expressly stated in
* the OpenSSL open source license shall be deemed granted or received
* expressly, by implication, estoppel, or otherwise.
*
* No assurances are provided by Nokia that the Contribution does not
* infringe the patent or other intellectual property rights of any third
* party or that the license provides you with all the necessary rights
* to make use of the Contribution.
*
* THE SOFTWARE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. IN
* ADDITION TO THE DISCLAIMERS INCLUDED IN THE LICENSE, NOKIA
* SPECIFICALLY DISCLAIMS ANY LIABILITY FOR CLAIMS BROUGHT BY YOU OR ANY
* OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OR
* OTHERWISE.
*/
#ifndef OPENSSL_HEADER_SSL_INTERNAL_H
#define OPENSSL_HEADER_SSL_INTERNAL_H
#include <openssl/base.h>
#include <stdlib.h>
#include <limits>
#include <new>
#include <type_traits>
#include <utility>
#include <openssl/aead.h>
#include <openssl/err.h>
#include <openssl/lhash.h>
#include <openssl/mem.h>
#include <openssl/ssl.h>
#include <openssl/span.h>
#include <openssl/stack.h>
#include "../crypto/err/internal.h"
#include "../crypto/internal.h"
#if defined(OPENSSL_WINDOWS)
// Windows defines struct timeval in winsock2.h.
OPENSSL_MSVC_PRAGMA(warning(push, 3))
#include <winsock2.h>
OPENSSL_MSVC_PRAGMA(warning(pop))
#else
#include <sys/time.h>
#endif
namespace bssl {
struct SSL_HANDSHAKE;
struct SSL_PROTOCOL_METHOD;
// C++ utilities.
// New behaves like |new| but uses |OPENSSL_malloc| for memory allocation. It
// returns nullptr on allocation error. It only implements single-object
// allocation and not new T[n].
//
// Note: unlike |new|, this does not support non-public constructors.
template <typename T, typename... Args>
T *New(Args &&... args) {
void *t = OPENSSL_malloc(sizeof(T));
if (t == nullptr) {
OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
return nullptr;
}
return new (t) T(std::forward<Args>(args)...);
}
// Delete behaves like |delete| but uses |OPENSSL_free| to release memory.
//
// Note: unlike |delete| this does not support non-public destructors.
template <typename T>
void Delete(T *t) {
if (t != nullptr) {
t->~T();
OPENSSL_free(t);
}
}
// All types with kAllowUniquePtr set may be used with UniquePtr. Other types
// may be C structs which require a |BORINGSSL_MAKE_DELETER| registration.
namespace internal {
template <typename T>
struct DeleterImpl<T, typename std::enable_if<T::kAllowUniquePtr>::type> {
static void Free(T *t) { Delete(t); }
};
}
// MakeUnique behaves like |std::make_unique| but returns nullptr on allocation
// error.
template <typename T, typename... Args>
UniquePtr<T> MakeUnique(Args &&... args) {
return UniquePtr<T>(New<T>(std::forward<Args>(args)...));
}
#if defined(BORINGSSL_ALLOW_CXX_RUNTIME)
#define HAS_VIRTUAL_DESTRUCTOR
#define PURE_VIRTUAL = 0
#else
// HAS_VIRTUAL_DESTRUCTOR should be declared in any base class which defines a
// virtual destructor. This avoids a dependency on |_ZdlPv| and prevents the
// class from being used with |delete|.
#define HAS_VIRTUAL_DESTRUCTOR \
void operator delete(void *) { abort(); }
// PURE_VIRTUAL should be used instead of = 0 when defining pure-virtual
// functions. This avoids a dependency on |__cxa_pure_virtual| but loses
// compile-time checking.
#define PURE_VIRTUAL { abort(); }
#endif
// CONSTEXPR_ARRAY works around a VS 2015 bug where ranged for loops don't work
// on constexpr arrays.
#if defined(_MSC_VER) && !defined(__clang__) && _MSC_VER < 1910
#define CONSTEXPR_ARRAY const
#else
#define CONSTEXPR_ARRAY constexpr
#endif
// Array<T> is an owning array of elements of |T|.
template <typename T>
class Array {
public:
// Array's default constructor creates an empty array.
Array() {}
Array(const Array &) = delete;
Array(Array &&other) { *this = std::move(other); }
~Array() { Reset(); }
Array &operator=(const Array &) = delete;
Array &operator=(Array &&other) {
Reset();
other.Release(&data_, &size_);
return *this;
}
const T *data() const { return data_; }
T *data() { return data_; }
size_t size() const { return size_; }
bool empty() const { return size_ == 0; }
const T &operator[](size_t i) const { return data_[i]; }
T &operator[](size_t i) { return data_[i]; }
T *begin() { return data_; }
const T *cbegin() const { return data_; }
T *end() { return data_ + size_; }
const T *cend() const { return data_ + size_; }
void Reset() { Reset(nullptr, 0); }
// Reset releases the current contents of the array and takes ownership of the
// raw pointer supplied by the caller.
void Reset(T *new_data, size_t new_size) {
for (size_t i = 0; i < size_; i++) {
data_[i].~T();
}
OPENSSL_free(data_);
data_ = new_data;
size_ = new_size;
}
// Release releases ownership of the array to a raw pointer supplied by the
// caller.
void Release(T **out, size_t *out_size) {
*out = data_;
*out_size = size_;
data_ = nullptr;
size_ = 0;
}
// Init replaces the array with a newly-allocated array of |new_size|
// default-constructed copies of |T|. It returns true on success and false on
// error.
//
// Note that if |T| is a primitive type like |uint8_t|, it is uninitialized.
bool Init(size_t new_size) {
Reset();
if (new_size == 0) {
return true;
}
if (new_size > std::numeric_limits<size_t>::max() / sizeof(T)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_OVERFLOW);
return false;
}
data_ = reinterpret_cast<T*>(OPENSSL_malloc(new_size * sizeof(T)));
if (data_ == nullptr) {
OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
return false;
}
size_ = new_size;
for (size_t i = 0; i < size_; i++) {
new (&data_[i]) T;
}
return true;
}
// CopyFrom replaces the array with a newly-allocated copy of |in|. It returns
// true on success and false on error.
bool CopyFrom(Span<const uint8_t> in) {
if (!Init(in.size())) {
return false;
}
OPENSSL_memcpy(data_, in.data(), in.size());
return true;
}
private:
T *data_ = nullptr;
size_t size_ = 0;
};
// CBBFinishArray behaves like |CBB_finish| but stores the result in an Array.
bool CBBFinishArray(CBB *cbb, Array<uint8_t> *out);
// Protocol versions.
//
// Due to DTLS's historical wire version differences and to support multiple
// variants of the same protocol during development, 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. Draft TLS 1.3
// variants all map to TLS 1.3. 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 *ssl, uint16_t *out_min_version,
uint16_t *out_max_version);
// ssl_supports_version returns whether |hs| supports |version|.
bool ssl_supports_version(SSL_HANDSHAKE *hs, uint16_t version);
// ssl_add_supported_versions writes the supported versions of |hs| to |cbb|, in
// decreasing preference order.
bool ssl_add_supported_versions(SSL_HANDSHAKE *hs, CBB *cbb);
// 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_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);
// ssl_is_draft21 returns whether the version corresponds to a draft21 TLS 1.3
// variant.
bool ssl_is_draft21(uint16_t version);
// ssl_is_resumption_experiment returns whether the version corresponds to a
// TLS 1.3 resumption experiment.
bool ssl_is_resumption_experiment(uint16_t version);
// ssl_is_resumption_variant returns whether the version corresponds to a
// TLS 1.3 resumption experiment.
bool ssl_is_resumption_variant(enum tls13_variant_t variant);
// ssl_is_resumption_client_ccs_experiment returns whether the version
// corresponds to a TLS 1.3 resumption experiment that sends a client CCS.
bool ssl_is_resumption_client_ccs_experiment(uint16_t version);
// ssl_is_resumption_record_version_experiment returns whether the version
// corresponds to a TLS 1.3 resumption experiment that modifies the record
// version.
bool ssl_is_resumption_record_version_experiment(uint16_t version);
// Cipher suites.
} // namespace bssl
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;
// id is the cipher suite value bitwise OR-d with 0x03000000.
uint32_t 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;
};
namespace bssl {
// 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 0x00000001u
#define SSL_aECDSA 0x00000002u
// SSL_aPSK is set for both PSK and ECDHE_PSK.
#define SSL_aPSK 0x00000004u
#define SSL_aGENERIC 0x00000008u
#define SSL_aCERT (SSL_aRSA | 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_eNULL 0x00000020u
#define SSL_CHACHA20POLY1305 0x00000040u
#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
#define SSL_SHA384 0x00000004u
// SSL_AEAD is set for all AEADs.
#define SSL_AEAD 0x00000008u
// 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_DIGEST is the number of digest types which exist. When adding a new
// one, update the table in ssl_cipher.c.
#define SSL_MAX_DIGEST 4
// 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, int is_dtls);
// 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 |ssl_cipher_preference_list_st| 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|.
bool ssl_create_cipher_list(
struct ssl_cipher_preference_list_st **out_cipher_list,
const char *rule_str, bool strict);
// ssl_cipher_get_value returns the cipher suite id of |cipher|.
uint16_t ssl_cipher_get_value(const SSL_CIPHER *cipher);
// 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.
uint32_t ssl_cipher_auth_mask_for_key(const EVP_PKEY *key);
// 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);
// Transcript layer.
// SSLTranscript maintains the handshake transcript as a combination of a
// buffer and running hash.
class SSLTranscript {
public:
SSLTranscript();
~SSLTranscript();
// 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.
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();
// CopyHashContext copies the hash context into |ctx| and returns true on
// success.
bool CopyHashContext(EVP_MD_CTX *ctx);
Span<const uint8_t> buffer() {
return MakeConstSpan(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);
// GetSSL3CertVerifyHash writes the SSL 3.0 CertificateVerify hash into the
// bytes pointed to by |out| and writes the number of bytes to
// |*out_len|. |out| must have room for |EVP_MAX_MD_SIZE| bytes. It returns
// one on success and zero on failure.
bool GetSSL3CertVerifyHash(uint8_t *out, size_t *out_len,
const SSL_SESSION *session,
uint16_t signature_algorithm);
// 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);
private:
// buffer_, if non-null, contains the handshake transcript.
UniquePtr<BUF_MEM> buffer_;
// hash, if initialized with an |EVP_MD|, maintains the handshake hash. For
// TLS 1.1 and below, it is the SHA-1 half.
ScopedEVP_MD_CTX hash_;
// md5, if initialized with an |EVP_MD|, maintains the MD5 half of the
// handshake hash for TLS 1.1 and below.
ScopedEVP_MD_CTX md5_;
};
// 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, Span<const char> 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:
SSLAEADContext(uint16_t version, bool is_dtls, 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(bool is_dtls);
// 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 normalized
// protocol version, so DTLS 1.0 is represented as 0x0301, not 0xffef.
static UniquePtr<SSLAEADContext> Create(enum evp_aead_direction_t direction,
uint16_t version, int is_dtls,
const SSL_CIPHER *cipher,
Span<const uint8_t> enc_key,
Span<const uint8_t> mac_key,
Span<const uint8_t> fixed_iv);
// SetVersionIfNullCipher sets the version the SSLAEADContext for the null
// cipher, to make version-specific determinations in the record layer prior
// to a cipher being selected.
void SetVersionIfNullCipher(uint16_t version);
// ProtocolVersion returns the protocol version associated with this
// SSLAEADContext. It can only be called once |version_| has been set to a
// valid value.
uint16_t ProtocolVersion() const;
// RecordVersion returns the record version that should be used with this
// SSLAEADContext for record construction and crypto.
uint16_t RecordVersion() const;
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;
// 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;
// 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,
const uint8_t seqnum[8], 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, const uint8_t seqnum[8], 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,
const uint8_t seqnum[8], 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 writes the additional data into |out| and returns the
// number of bytes written.
size_t GetAdditionalData(uint8_t out[13], uint8_t type,
uint16_t record_version, const uint8_t seqnum[8],
size_t plaintext_len);
const SSL_CIPHER *cipher_;
ScopedEVP_AEAD_CTX ctx_;
// fixed_nonce_ contains any bytes of the nonce that are fixed for all
// records.
uint8_t fixed_nonce_[12];
uint8_t fixed_nonce_len_ = 0, variable_nonce_len_ = 0;
// version_ is the wire version that should be used with this AEAD.
uint16_t version_;
// is_dtls_ is whether DTLS is being used with this AEAD.
bool is_dtls_;
// 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;
// omit_length_in_ad_ is true if the length should be omitted in the
// AEAD's ad parameter.
bool omit_length_in_ad_ : 1;
// omit_version_in_ad_ is true if the version should be omitted
// in the AEAD's ad parameter.
bool omit_version_in_ad_ : 1;
// omit_ad_ is true if the AEAD's ad parameter should be omitted.
bool omit_ad_ : 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;
};
// DTLS replay bitmap.
// DTLS1_BITMAP maintains a sliding window of 64 sequence numbers to detect
// replayed packets. It should be initialized by zeroing every field.
struct DTLS1_BITMAP {
// map is a bit mask of the last 64 sequence numbers. Bit
// |1<<i| corresponds to |max_seq_num - i|.
uint64_t map = 0;
// max_seq_num is the largest sequence number seen so far as a 64-bit
// integer.
uint64_t max_seq_num = 0;
};
// Record layer.
// ssl_record_sequence_update increments the sequence number in |seq|. It
// returns one on success and zero on wraparound.
int ssl_record_sequence_update(uint8_t *seq, size_t seq_len);
// 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.
enum ssl_open_record_t dtls_open_record(SSL *ssl, uint8_t *out_type,
Span<uint8_t> *out,
size_t *out_consumed,
uint8_t *out_alert, Span<uint8_t> in);
// ssl_seal_align_prefix_len returns the length of the prefix before the start
// of the bulk of the ciphertext when sealing a record with |ssl|. Callers may
// use this to align buffers.
//
// Note when TLS 1.0 CBC record-splitting is enabled, this includes the one byte
// record and is the offset into second record's ciphertext. Thus sealing a
// small record may result in a smaller output than this value.
//
// TODO(davidben): Is this alignment valuable? Record-splitting makes this a
// mess.
size_t ssl_seal_align_prefix_len(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 one on success
// and zero 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
// |ssl_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.
int 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);
enum dtls1_use_epoch_t {
dtls1_use_previous_epoch,
dtls1_use_current_epoch,
};
// dtls_max_seal_overhead returns the maximum overhead, in bytes, of sealing a
// record.
size_t dtls_max_seal_overhead(const SSL *ssl, enum dtls1_use_epoch_t use_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, enum dtls1_use_epoch_t use_epoch);
// dtls_seal_record implements |tls_seal_record| for DTLS. |use_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|.
int dtls_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,
enum dtls1_use_epoch_t use_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_has_private_key returns one if |ssl| has a private key
// configured and zero otherwise.
int ssl_has_private_key(const SSL *ssl);
// 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_private_key_supports_signature_algorithm returns whether |hs|'s private
// key supports |sigalg|.
bool ssl_private_key_supports_signature_algorithm(SSL_HANDSHAKE *hs,
uint16_t sigalg);
// 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);
// Custom extensions
} // namespace bssl
// |SSL_CUSTOM_EXTENSION| is a structure that contains information about
// custom-extension callbacks. It is defined unnamespaced for compatibility with
// |STACK_OF(SSL_CUSTOM_EXTENSION)|.
typedef struct ssl_custom_extension {
SSL_custom_ext_add_cb add_callback;
void *add_arg;
SSL_custom_ext_free_cb free_callback;
SSL_custom_ext_parse_cb parse_callback;
void *parse_arg;
uint16_t value;
} SSL_CUSTOM_EXTENSION;
DEFINE_STACK_OF(SSL_CUSTOM_EXTENSION)
namespace bssl {
void SSL_CUSTOM_EXTENSION_free(SSL_CUSTOM_EXTENSION *custom_extension);
int custom_ext_add_clienthello(SSL_HANDSHAKE *hs, CBB *extensions);
int custom_ext_parse_serverhello(SSL_HANDSHAKE *hs, int *out_alert,
uint16_t value, const CBS *extension);
int custom_ext_parse_clienthello(SSL_HANDSHAKE *hs, int *out_alert,
uint16_t value, const CBS *extension);
int custom_ext_add_serverhello(SSL_HANDSHAKE *hs, CBB *extensions);
// Key shares.
// SSLKeyShare abstracts over Diffie-Hellman-like key exchanges.
class SSLKeyShare {
public:
virtual ~SSLKeyShare() {}
static constexpr bool kAllowUniquePtr = true;
HAS_VIRTUAL_DESTRUCTOR
// 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 PURE_VIRTUAL;
// Offer generates a keypair and writes the public value to
// |out_public_key|. It returns true on success and false on error.
virtual bool Offer(CBB *out_public_key) PURE_VIRTUAL;
// Accept performs a key exchange against the |peer_key| generated by |offer|.
// On success, it returns true, writes the public value to |out_public_key|,
// and sets |*out_secret| the shared secret. On failure, it returns false and
// sets |*out_alert| to an alert to send to the peer.
//
// The default implementation calls |Offer| and then |Finish|, assuming a key
// exchange protocol where the peers are symmetric.
virtual bool Accept(CBB *out_public_key, Array<uint8_t> *out_secret,
uint8_t *out_alert, Span<const uint8_t> peer_key);
// Finish performs a key exchange against the |peer_key| generated by
// |Accept|. On success, it returns true and sets |*out_secret| to the shared
// secret. On failure, it returns zero and sets |*out_alert| to an alert to
// send to the peer.
virtual bool Finish(Array<uint8_t> *out_secret, uint8_t *out_alert,
Span<const uint8_t> peer_key) PURE_VIRTUAL;
};
// 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 one. Otherwise, it returns
// zero.
int 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 one. Otherwise, it returns zero.
int ssl_name_to_group_id(uint16_t *out_group_id, const char *name, size_t len);
// 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
// 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);
// dtls_has_unprocessed_handshake_data behaves like
// |tls_has_unprocessed_handshake_data| for DTLS.
bool dtls_has_unprocessed_handshake_data(const SSL *ssl);
struct DTLS_OUTGOING_MESSAGE {
DTLS_OUTGOING_MESSAGE() {}
DTLS_OUTGOING_MESSAGE(const DTLS_OUTGOING_MESSAGE &) = delete;
DTLS_OUTGOING_MESSAGE &operator=(const DTLS_OUTGOING_MESSAGE &) = delete;
~DTLS_OUTGOING_MESSAGE() { Clear(); }
void Clear();
uint8_t *data = nullptr;
uint32_t len = 0;
uint16_t epoch = 0;
bool is_ccs = false;
};
// dtls_clear_outgoing_messages releases all buffered outgoing messages.
void dtls_clear_outgoing_messages(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(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 MakeSpan(data(), size()); }
Span<uint8_t> remaining() {
return MakeSpan(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;
};
// 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_has_certificate returns one if a certificate and private key are
// configured and zero otherwise.
int ssl_has_certificate(const SSL *ssl);
// 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_add_cert_chain adds |ssl|'s certificate chain to |cbb| in the format used
// by a TLS Certificate message. If there is no certificate chain, it emits an
// empty certificate list. It returns one on success and zero on error.
int ssl_add_cert_chain(SSL *ssl, CBB *cbb);
// ssl_cert_check_digital_signature_key_usage parses the DER-encoded, X.509
// certificate in |in| and returns one if doesn't specify a key usage or, if it
// does, if it includes digitalSignature. Otherwise it pushes to the error
// queue and returns zero.
int ssl_cert_check_digital_signature_key_usage(const CBS *in);
// 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_client_CA_list parses a CA list from |cbs| in the format used by a
// TLS CertificateRequest message. 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_client_CA_list(SSL *ssl,
uint8_t *out_alert,
CBS *cbs);
// ssl_has_client_CAs returns there are configured CAs.
bool ssl_has_client_CAs(SSL *ssl);
// ssl_add_client_CA_list adds the configured CA list to |cbb| in the format
// used by a TLS CertificateRequest message. It returns one on success and zero
// on error.
int ssl_add_client_CA_list(SSL *ssl, 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.
int ssl_check_leaf_certificate(SSL_HANDSHAKE *hs, EVP_PKEY *pkey,
const CRYPTO_BUFFER *leaf);
// ssl_on_certificate_selected is called once the certificate has been selected.
// It finalizes the certificate and initializes |hs->local_pubkey|. It returns
// one on success and zero on error.
int ssl_on_certificate_selected(SSL_HANDSHAKE *hs);
// 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 one on success and zero on error.
int tls13_init_key_schedule(SSL_HANDSHAKE *hs, const uint8_t *psk,
size_t psk_len);
// tls13_init_early_key_schedule initializes the handshake hash and key
// derivation state from the resumption secret and incorporates the PSK to
// derive the early secrets. It returns one on success and zero on error.
int tls13_init_early_key_schedule(SSL_HANDSHAKE *hs, const uint8_t *psk,
size_t psk_len);
// tls13_advance_key_schedule incorporates |in| into the key schedule with
// HKDF-Extract. It returns one on success and zero on error.
int tls13_advance_key_schedule(SSL_HANDSHAKE *hs, const uint8_t *in,
size_t len);
// tls13_set_traffic_key sets the read or write traffic keys to
// |traffic_secret|. It returns one on success and zero on error.
int tls13_set_traffic_key(SSL *ssl, enum evp_aead_direction_t direction,
const uint8_t *traffic_secret,
size_t traffic_secret_len);
// tls13_derive_early_secrets derives the early traffic secret. It returns one
// on success and zero on error.
int tls13_derive_early_secrets(SSL_HANDSHAKE *hs);
// tls13_derive_handshake_secrets derives the handshake traffic secret. It
// returns one on success and zero on error.
int tls13_derive_handshake_secrets(SSL_HANDSHAKE *hs);
// tls13_rotate_traffic_key derives the next read or write traffic secret. It
// returns one on success and zero on error.
int 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 one on success and zero on error.
int tls13_derive_application_secrets(SSL_HANDSHAKE *hs);
// tls13_derive_resumption_secret derives the |resumption_secret|.
int tls13_derive_resumption_secret(SSL_HANDSHAKE *hs);
// tls13_export_keying_material provides an exporter interface to use the
// |exporter_secret|.
int tls13_export_keying_material(SSL *ssl, uint8_t *out, size_t out_len,
const char *label, size_t label_len,
const uint8_t *context, size_t context_len,
int use_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 1 if this is for the Server Finished and
// 0 for the Client Finished.
int tls13_finished_mac(SSL_HANDSHAKE *hs, uint8_t *out,
size_t *out_len, int 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);
// tls13_write_psk_binder calculates the PSK binder value and replaces the last
// bytes of |msg| with the resulting value. It returns 1 on success, and 0 on
// failure.
int tls13_write_psk_binder(SSL_HANDSHAKE *hs, uint8_t *msg, size_t len);
// tls13_verify_psk_binder verifies that the handshake transcript, truncated
// up to the binders has a valid signature using the value of |session|'s
// resumption secret. It returns 1 on success, and 0 on failure.
int tls13_verify_psk_binder(SSL_HANDSHAKE *hs, SSL_SESSION *session,
const SSLMessage &msg, CBS *binders);
// 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_x509_lookup,
ssl_hs_channel_id_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,
};
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;
// 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;
// session_id is the session ID in the ClientHello, used for the experimental
// TLS 1.3 variant.
uint8_t session_id[SSL_MAX_SSL_SESSION_ID_LENGTH] = {0};
uint8_t session_id_len = 0;
size_t hash_len = 0;
uint8_t secret[EVP_MAX_MD_SIZE] = {0};
uint8_t early_traffic_secret[EVP_MAX_MD_SIZE] = {0};
uint8_t client_handshake_secret[EVP_MAX_MD_SIZE] = {0};
uint8_t server_handshake_secret[EVP_MAX_MD_SIZE] = {0};
uint8_t client_traffic_secret_0[EVP_MAX_MD_SIZE] = {0};
uint8_t server_traffic_secret_0[EVP_MAX_MD_SIZE] = {0};
uint8_t expected_client_finished[EVP_MAX_MD_SIZE] = {0};
union {
// sent is a bitset where the bits correspond to elements of kExtensions
// in t1_lib.c. 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;
union {
// sent is a bitset where the bits correspond to elements of
// |client_custom_extensions| in the |SSL_CTX|. Each bit is set if that
// extension was sent in a ClientHello. It's not used by servers.
uint16_t sent = 0;
// received is a bitset, like |sent|, but is used by servers to record
// which custom extensions were received from a client. The bits here
// correspond to |server_custom_extensions|.
uint16_t received;
} custom_extensions;
// retry_group is the group ID selected by the server in HelloRetryRequest in
// TLS 1.3.
uint16_t retry_group = 0;
// error, if |wait| is |ssl_hs_error|, is the error the handshake failed on.
UniquePtr<ERR_SAVE_STATE> error;
// key_share is the current key exchange instance.
UniquePtr<SSLKeyShare> key_share;
// transcript is the current handshake transcript.
SSLTranscript transcript;
// cookie is the value of the cookie received from the server, if any.
Array<uint8_t> cookie;
// key_share_bytes is the value of the previously sent KeyShare extension by
// the client in TLS 1.3.
Array<uint8_t> key_share_bytes;
// ecdh_public_key, for servers, is the key share to be sent to the client in
// TLS 1.3.
Array<uint8_t> ecdh_public_key;
// 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_key is the peer's ECDH key for a TLS 1.2 client.
Array<uint8_t> peer_key;
// 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, on the client, contains the list of CAs received in a
// CertificateRequest message.
UniquePtr<STACK_OF(CRYPTO_BUFFER)> ca_names;
// 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;
// local_pubkey is the public key we are authenticating as.
UniquePtr<EVP_PKEY> local_pubkey;
// 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;
// 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;
// scts_requested is true if the SCT extension is in the ClientHello.
bool scts_requested:1;
// needs_psk_binder is true if the ClientHello has a placeholder PSK binder to
// be filled in.
bool needs_psk_binder:1;
bool received_hello_retry_request:1;
bool received_custom_extension: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;
// 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;
// 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;
// early_data_written is the amount of early data that has been written by the
// record layer.
uint16_t early_data_written = 0;
};
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_post_handshake processes a post-handshake message. It returns one on
// success and zero on failure.
int tls13_post_handshake(SSL *ssl, const SSLMessage &msg);
int tls13_process_certificate(SSL_HANDSHAKE *hs, const SSLMessage &msg,
int allow_anonymous);
int 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 one, the verify_data is compared against
// |hs->expected_client_finished| rather than computed fresh.
int tls13_process_finished(SSL_HANDSHAKE *hs, const SSLMessage &msg,
int use_saved_value);
int 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);
int tls13_add_finished(SSL_HANDSHAKE *hs);
int tls13_process_new_session_ticket(SSL *ssl, const SSLMessage &msg);
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,
Array<uint8_t> *out_secret,
uint8_t *out_alert, CBS *contents);
bool ssl_ext_key_share_add_serverhello(SSL_HANDSHAKE *hs, CBB *out);
bool ssl_ext_pre_shared_key_parse_serverhello(SSL_HANDSHAKE *hs,
uint8_t *out_alert,
CBS *contents);
bool ssl_ext_pre_shared_key_parse_clienthello(
SSL_HANDSHAKE *hs, CBS *out_ticket, CBS *out_binders,
uint32_t *out_obfuscated_ticket_age, uint8_t *out_alert, CBS *contents);
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 one iff it's valid.
int ssl_is_sct_list_valid(const CBS *contents);
int ssl_write_client_hello(SSL_HANDSHAKE *hs);
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_alpn_protocol_allowed returns whether |protocol| is a valid server
// selection for |ssl|'s client preferences.
bool ssl_is_alpn_protocol_allowed(const SSL *ssl, 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);
struct SSL_EXTENSION_TYPE {
uint16_t type;
bool *out_present;
CBS *out_data;
};
// ssl_parse_extensions parses a TLS extensions block out of |cbs| and advances
// it. It writes the parsed extensions to pointers denoted by |ext_types|. On
// success, it fills in the |out_present| and |out_data| fields and returns one.
// Otherwise, it sets |*out_alert| to an alert to send and returns zero. Unknown
// extensions are rejected unless |ignore_unknown| is 1.
int ssl_parse_extensions(const CBS *cbs, uint8_t *out_alert,
const SSL_EXTENSION_TYPE *ext_types,
size_t num_ext_types, int ignore_unknown);
// ssl_verify_peer_cert verifies the peer certificate for |hs|.
enum ssl_verify_result_t ssl_verify_peer_cert(SSL_HANDSHAKE *hs);
enum ssl_hs_wait_t ssl_get_finished(SSL_HANDSHAKE *hs);
bool ssl_send_finished(SSL_HANDSHAKE *hs);
bool ssl_output_cert_chain(SSL *ssl);
// SSLKEYLOGFILE functions.
// ssl_log_secret logs |secret| with label |label|, if logging is enabled for
// |ssl|. It returns one on success and zero on failure.
int ssl_log_secret(const SSL *ssl, const char *label, const uint8_t *secret,
size_t secret_len);
// ClientHello functions.
int ssl_client_hello_init(SSL *ssl, SSL_CLIENT_HELLO *out,
const SSLMessage &msg);
int ssl_client_hello_get_extension(const SSL_CLIENT_HELLO *client_hello,
CBS *out, uint16_t extension_type);
int ssl_client_cipher_list_contains_cipher(const SSL_CLIENT_HELLO *client_hello,
uint16_t id);
// GREASE.
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_get_grease_value returns a GREASE value for |ssl|. 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 *ssl, 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 one on success and zero on
// error.
int 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 one on
// success and zero if |pkey| may not be used at those versions.
int 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 |hs|'s private key based on the peer's preferences and the algorithms
// supported. It returns one on success and zero on error.
int tls1_choose_signature_algorithm(SSL_HANDSHAKE *hs, uint16_t *out);
// tls12_add_verify_sigalgs adds the signature algorithms acceptable for the
// peer signature to |out|. It returns one on success and zero on error.
int tls12_add_verify_sigalgs(const SSL *ssl, CBB *out);
// tls12_check_peer_sigalg checks if |sigalg| is acceptable for the peer
// signature. It returns one on success and zero on error, setting |*out_alert|
// to an alert to send.
int tls12_check_peer_sigalg(SSL *ssl, uint8_t *out_alert, uint16_t sigalg);
// Underdocumented functions.
//
// Functions below here haven't been touched up and may be underdocumented.
#define TLSEXT_CHANNEL_ID_SIZE 128
// From RFC4492, used in encoding the curve type in ECParameters
#define NAMED_CURVE_TYPE 3
struct CERT {
EVP_PKEY *privatekey;
// chain contains the certificate chain, with the leaf at the beginning. The
// first element of |chain| may be NULL to indicate that the leaf certificate
// has not yet been set.
// If |chain| != NULL -> len(chain) >= 1
// If |chain[0]| == NULL -> len(chain) >= 2.
// |chain[1..]| != NULL
STACK_OF(CRYPTO_BUFFER) *chain;
// x509_chain may contain a parsed copy of |chain[1..]|. 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;
// x509_leaf may contain a parsed copy of the first element of |chain|. 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;
// x509_stash contains the last |X509| object append to the 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;
// key_method, if non-NULL, is a set of callbacks to call for private key
// operations.
const SSL_PRIVATE_KEY_METHOD *key_method;
// 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;
// sigalgs, if non-NULL, is the set of signature algorithms supported by
// |privatekey| in decreasing order of preference.
uint16_t *sigalgs;
size_t num_sigalgs;
// 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);
void *cert_cb_arg;
// Optional X509_STORE for certificate validation. If NULL the parent SSL_CTX
// store is used instead.
X509_STORE *verify_store;
// Signed certificate timestamp list to be sent to the client, if requested
CRYPTO_BUFFER *signed_cert_timestamp_list;
// OCSP response to be sent to the client, if requested.
CRYPTO_BUFFER *ocsp_response;
// sid_ctx partitions the session space within a shared session cache or
// ticket key. Only sessions with a matching value will be accepted.
uint8_t sid_ctx_length;
uint8_t sid_ctx[SSL_MAX_SID_CTX_LENGTH];
// If enable_early_data is true, early data can be sent and accepted.
bool enable_early_data:1;
};
// |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)(SSL *ssl, SSLMessage *out);
// next_message is called to release the current handshake message.
void (*next_message)(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);
int (*write_app_data)(SSL *ssl, bool *out_needs_handshake, const uint8_t *buf,
int len);
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)(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)(SSL *ssl, CBB *cbb, bssl::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, bssl::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);
// add_alert adds an alert to the pending flight. It returns true on success
// and false on error.
bool (*add_alert)(SSL *ssl, uint8_t level, uint8_t desc);
// flush_flight flushes the pending flight to the transport. It returns one on
// success and <= 0 on error.
int (*flush_flight)(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 to |aead_ctx|. It returns
// true on success and false if changing the read state is forbidden at this
// point.
bool (*set_read_state)(SSL *ssl, UniquePtr<SSLAEADContext> aead_ctx);
// set_write_state sets |ssl|'s write cipher state to |aead_ctx|. It returns
// true on success and false if changing the write state is forbidden at this
// point.
bool (*set_write_state)(SSL *ssl, UniquePtr<SSLAEADContext> aead_ctx);
};
// 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);
// 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;
// ssl_cipher_preference_list_st 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 ssl_cipher_preference_list_st {
STACK_OF(SSL_CIPHER) *ciphers;
uint8_t *in_group_flags;
};
struct tlsext_ticket_key {
static constexpr bool kAllowUniquePtr = true;
uint8_t name[SSL_TICKET_KEY_NAME_LEN];
uint8_t hmac_key[16];
uint8_t aes_key[16];
// 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;
};
} // namespace bssl
DECLARE_LHASH_OF(SSL_SESSION)
namespace bssl {
// SSLContext backs the public |SSL_CTX| type. Due to compatibility constraints,
// it is a base class for |ssl_ctx_st|.
struct SSLContext {
const SSL_PROTOCOL_METHOD *method;
const SSL_X509_METHOD *x509_method;
// lock is used to protect various operations on this object.
CRYPTO_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 constrainted by |SSL_OP_NO_*|.
uint16_t conf_max_version;
// 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 constrainted by |SSL_OP_NO_*|.
uint16_t conf_min_version;
// tls13_variant is the variant of TLS 1.3 we are using for this
// configuration.
enum tls13_variant_t tls13_variant;
struct ssl_cipher_preference_list_st *cipher_list;
X509_STORE *cert_store;
LHASH_OF(SSL_SESSION) *sessions;
// 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 *session_cache_head;
SSL_SESSION *session_cache_tail;
// handshakes_since_cache_flush is the number of successful handshakes since
// the last cache flush.
int handshakes_since_cache_flush;
// 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;
// session_timeout is the default lifetime for new sessions in TLS 1.2 and
// earlier, in seconds.
uint32_t 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;
// 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);
void (*remove_session_cb)(SSL_CTX *ctx, SSL_SESSION *sess);
SSL_SESSION *(*get_session_cb)(SSL *ssl, const uint8_t *data, int len,
int *copy);
SSL_SESSION *(*get_session_cb_legacy)(SSL *ssl, uint8_t *data, int len,
int *copy);
CRYPTO_refcount_t references;
// if defined, these override the X509_verify_cert() calls
int (*app_verify_callback)(X509_STORE_CTX *store_ctx, void *arg);
void *app_verify_arg;
enum ssl_verify_result_t (*custom_verify_callback)(SSL *ssl,
uint8_t *out_alert);
// Default password callback.
pem_password_cb *default_passwd_callback;
// Default password callback user data.
void *default_passwd_callback_userdata;
// get client cert callback
int (*client_cert_cb)(SSL *ssl, X509 **out_x509, EVP_PKEY **out_pkey);
// get channel id callback
void (*channel_id_cb)(SSL *ssl, EVP_PKEY **out_pkey);
CRYPTO_EX_DATA ex_data;
// custom_*_extensions stores any callback sets for custom extensions. Note
// that these pointers will be NULL if the stack would otherwise be empty.
STACK_OF(SSL_CUSTOM_EXTENSION) *client_custom_extensions;
STACK_OF(SSL_CUSTOM_EXTENSION) *server_custom_extensions;
// Default values used when no per-SSL value is defined follow
void (*info_callback)(const SSL *ssl, int type, int value);
// what we put in client cert requests
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;
// Default values to use in SSL structures follow (these are copied by
// SSL_new)
uint32_t options;
uint32_t mode;
uint32_t max_cert_list;
CERT *cert;
// 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);
void *msg_callback_arg;
int verify_mode;
int (*default_verify_callback)(
int ok, X509_STORE_CTX *ctx); // called 'verify_callback' in the SSL
X509_VERIFY_PARAM *param;
// 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.
enum ssl_select_cert_result_t (*select_certificate_cb)(
const SSL_CLIENT_HELLO *);
// 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 *);
// 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;
// TLS extensions servername callback
int (*tlsext_servername_callback)(SSL *, int *, void *);
void *tlsext_servername_arg;
// RFC 4507 session ticket keys. |tlsext_ticket_key_current| may be NULL
// before the first handshake and |tlsext_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|.
struct tlsext_ticket_key *tlsext_ticket_key_current;
struct tlsext_ticket_key *tlsext_ticket_key_prev;
// Callback to support customisation of ticket key setting
int (*tlsext_ticket_key_cb)(SSL *ssl, uint8_t *name, uint8_t *iv,
EVP_CIPHER_CTX *ectx, HMAC_CTX *hctx, int enc);
// Server-only: psk_identity_hint is the default identity hint to send in
// PSK-based key exchanges.
char *psk_identity_hint;
unsigned int (*psk_client_callback)(SSL *ssl, const char *hint,
char *identity,
unsigned int max_identity_len,
uint8_t *psk, unsigned int max_psk_len);
unsigned int (*psk_server_callback)(SSL *ssl, const char *identity,
uint8_t *psk, unsigned int max_psk_len);
// 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);
void *next_protos_advertised_cb_arg;
// 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);
void *next_proto_select_cb_arg;
// 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);
void *alpn_select_cb_arg;
// For a client, this contains the list of supported protocols in wire
// format.
uint8_t *alpn_client_proto_list;
unsigned alpn_client_proto_list_len;
// SRTP profiles we are willing to do from RFC 5764
STACK_OF(SRTP_PROTECTION_PROFILE) *srtp_profiles;
// Supported group values inherited by SSL structure
size_t supported_group_list_len;
uint16_t *supported_group_list;
// The client's Channel ID private key.
EVP_PKEY *tlsext_channel_id_private;
// 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);
// 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);
// pool is used for all |CRYPTO_BUFFER|s in case we wish to share certificate
// memory.
CRYPTO_BUFFER_POOL *pool;
// ticket_aead_method contains function pointers for opening and sealing
// session tickets.
const SSL_TICKET_AEAD_METHOD *ticket_aead_method;
// verify_sigalgs, if not empty, is the set of signature algorithms
// accepted from the peer in decreasing order of preference.
uint16_t *verify_sigalgs;
size_t num_verify_sigalgs;
// 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;
// tlsext_channel_id_enabled is one if Channel ID is enabled and zero
// otherwise. For a server, means that we'll accept Channel IDs from clients.
// For a client, means that we'll advertise support.
bool tlsext_channel_id_enabled:1;
// grease_enabled is one if draft-davidben-tls-grease-01 is enabled and zero
// otherwise.
bool grease_enabled:1;
// allow_unknown_alpn_protos is one if the client allows unsolicited ALPN
// protocols from the peer.
bool allow_unknown_alpn_protos:1;
// ed25519_enabled is one if Ed25519 is advertised in the handshake.
bool ed25519_enabled:1;
};
// 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,
};
struct SSL3_STATE {
static constexpr bool kAllowUniquePtr = true;
SSL3_STATE();
~SSL3_STATE();
uint8_t read_sequence[8] = {0};
uint8_t write_sequence[8] = {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;
// partial write - check the numbers match
unsigned int wnum = 0; // number of bytes sent so far
int wpend_tot = 0; // number bytes written
int wpend_type = 0;
int wpend_ret = 0; // number of bytes submitted
const uint8_t *wpend_buf = nullptr;
// 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 alert_dispatch = 0;
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_NOTHING;
// 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;
// skip_early_data instructs the record layer to skip unexpected early data
// messages when 0RTT is rejected.
bool skip_early_data:1;
// have_version is true if the connection's final version is known. Otherwise
// the version has not been negotiated yet.
bool have_version: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;
// In a client, this means that the server supported Channel ID and that a
// Channel ID was sent. In a server it means that we echoed support for
// Channel IDs and that tlsext_channel_id will be valid after the
// handshake.
bool tlsext_channel_id_valid:1;
// key_update_pending is true if we have a KeyUpdate acknowledgment
// outstanding.
bool key_update_pending:1;
// wpend_pending is true if we have a pending write outstanding.
bool wpend_pending:1;
uint8_t send_alert[2] = {0};
// hs_buf is the buffer of handshake data to process.
UniquePtr<BUF_MEM> hs_buf;
// 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;
// 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;
uint8_t write_traffic_secret[EVP_MAX_MD_SIZE] = {0};
uint8_t read_traffic_secret[EVP_MAX_MD_SIZE] = {0};
uint8_t exporter_secret[EVP_MAX_MD_SIZE] = {0};
uint8_t early_exporter_secret[EVP_MAX_MD_SIZE] = {0};
uint8_t write_traffic_secret_len = 0;
uint8_t read_traffic_secret_len = 0;
uint8_t exporter_secret_len = 0;
uint8_t early_exporter_secret_len = 0;
// Connection binding to prevent renegotiation attacks
uint8_t previous_client_finished[12] = {0};
uint8_t previous_client_finished_len = 0;
uint8_t previous_server_finished_len = 0;
uint8_t previous_server_finished[12] = {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 |tlsext_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 tlsext_channel_id[64] = {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;
};
// lengths of messages
#define DTLS1_COOKIE_LENGTH 256
#define DTLS1_RT_HEADER_LENGTH 13
#define DTLS1_HM_HEADER_LENGTH 12
#define DTLS1_CCS_HEADER_LENGTH 1
#define DTLS1_AL_HEADER_LENGTH 2
struct hm_header_st {
uint8_t type;
uint32_t msg_len;
uint16_t seq;
uint32_t frag_off;
uint32_t frag_len;
};
// An hm_fragment is an incoming DTLS message, possibly not yet assembled.
struct hm_fragment {
static constexpr bool kAllowUniquePtr = true;
hm_fragment() {}
hm_fragment(const hm_fragment &) = delete;
hm_fragment &operator=(const hm_fragment &) = delete;
~hm_fragment();
// type is the type of the message.
uint8_t type = 0;
// seq is the sequence number of this message.
uint16_t seq = 0;
// msg_len is the length of the message body.
uint32_t msg_len = 0;
// data is a pointer to the message, including message header. It has length
// |DTLS1_HM_HEADER_LENGTH| + |msg_len|.
uint8_t *data = nullptr;
// reassembly is a bitmask of |msg_len| bits corresponding to which parts of
// the message have been received. It is NULL if the message is complete.
uint8_t *reassembly = nullptr;
};
struct OPENSSL_timeval {
uint64_t tv_sec;
uint32_t tv_usec;
};
struct DTLS1_STATE {
static constexpr bool kAllowUniquePtr = true;
DTLS1_STATE();
~DTLS1_STATE();
// 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;
uint8_t cookie[DTLS1_COOKIE_LENGTH] = {0};
size_t cookie_len = 0;
// The current data and handshake epoch. This is initially undefined, and
// starts at zero once the initial handshake is completed.
uint16_t r_epoch = 0;
uint16_t w_epoch = 0;
// records being received in the current epoch
DTLS1_BITMAP bitmap;
uint16_t handshake_write_seq = 0;
uint16_t handshake_read_seq = 0;
// save last sequence number for retransmissions
uint8_t last_write_sequence[8] = {0};
UniquePtr<SSLAEADContext> last_aead_write_ctx;
// 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<hm_fragment> incoming_messages[SSL_MAX_HANDSHAKE_FLIGHT];
// outgoing_messages is the queue of outgoing messages from the last handshake
// flight.
DTLS_OUTGOING_MESSAGE outgoing_messages[SSL_MAX_HANDSHAKE_FLIGHT];
uint8_t outgoing_messages_len = 0;
// 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;
// Indicates when the last handshake msg or heartbeat sent will
// timeout.
struct OPENSSL_timeval next_timeout = {0, 0};
// timeout_duration_ms is the timeout duration in milliseconds.
unsigned timeout_duration_ms = 0;
};
// SSLConnection backs the public |SSL| type. Due to compatibility constraints,
// it is a base class for |ssl_st|.
struct SSLConnection {
// method is the method table corresponding to the current protocol (DTLS or
// TLS).
const SSL_PROTOCOL_METHOD *method;
// version is the protocol version.
uint16_t version;
// conf_max_version is the maximum acceptable protocol version configured by
// |SSL_set_max_proto_version|. Note this version is normalized in DTLS and is
// further constrainted by |SSL_OP_NO_*|.
uint16_t conf_max_version;
// conf_min_version is the minimum acceptable protocol version configured by
// |SSL_set_min_proto_version|. Note this version is normalized in DTLS and is
// further constrainted by |SSL_OP_NO_*|.
uint16_t conf_min_version;
// tls13_variant is the variant of TLS 1.3 we are using for this
// configuration.
enum tls13_variant_t tls13_variant;
uint16_t max_send_fragment;
// 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
BIO *rbio; // used by SSL_read
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.
enum ssl_hs_wait_t (*do_handshake)(SSL_HANDSHAKE *hs);
SSL3_STATE *s3; // SSLv3 variables
DTLS1_STATE *d1; // DTLSv1 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);
void *msg_callback_arg;
X509_VERIFY_PARAM *param;
// crypto
struct ssl_cipher_preference_list_st *cipher_list;
// session info
// client cert?
// This is used to hold the server certificate used
CERT *cert;
// initial_timeout_duration_ms is the default DTLS timeout duration in
// milliseconds. It's used to initialize the timer any time it's restarted.
unsigned initial_timeout_duration_ms;
// session is the configured session to be offered by the client. This session
// is immutable.
SSL_SESSION *session;
int (*verify_callback)(int ok,
X509_STORE_CTX *ctx); // fail if callback returns 0
enum ssl_verify_result_t (*custom_verify_callback)(SSL *ssl,
uint8_t *out_alert);
void (*info_callback)(const SSL *ssl, int type, int value);
// Server-only: psk_identity_hint is the identity hint to send in
// PSK-based key exchanges.
char *psk_identity_hint;
unsigned int (*psk_client_callback)(SSL *ssl, const char *hint,
char *identity,
unsigned int max_identity_len,
uint8_t *psk, unsigned int max_psk_len);
unsigned int (*psk_server_callback)(SSL *ssl, const char *identity,
uint8_t *psk, unsigned int max_psk_len);
SSL_CTX *ctx;
// extra application data
CRYPTO_EX_DATA ex_data;
// for server side, keep the list of CA_dn we can use
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;
uint32_t options; // protocol behaviour
uint32_t mode; // API behaviour
uint32_t max_cert_list;
char *tlsext_hostname;
size_t supported_group_list_len;
uint16_t *supported_group_list; // our list
// session_ctx is the |SSL_CTX| used for the session cache and related
// settings.
SSL_CTX *session_ctx;
// srtp_profiles is the list of configured SRTP protection profiles for
// DTLS-SRTP.
STACK_OF(SRTP_PROTECTION_PROFILE) *srtp_profiles;
// srtp_profile is the selected SRTP protection profile for
// DTLS-SRTP.
const SRTP_PROTECTION_PROFILE *srtp_profile;
// The client's Channel ID private key.
EVP_PKEY *tlsext_channel_id_private;
// For a client, this contains the list of supported protocols in wire
// format.
uint8_t *alpn_client_proto_list;
unsigned alpn_client_proto_list_len;
// renegotiate_mode controls how peer renegotiation attempts are handled.
enum ssl_renegotiate_mode_t renegotiate_mode;
// verify_mode is a bitmask of |SSL_VERIFY_*| values.
uint8_t verify_mode;
// 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;
// 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;
// tlsext_channel_id_enabled is copied from the |SSL_CTX|. For a server,
// means that we'll accept Channel IDs from clients. For a client, means that
// we'll advertise support.
bool tlsext_channel_id_enabled: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;
// early_data_accepted is true if early data was accepted by the server.
bool early_data_accepted:1;
};
// From draft-ietf-tls-tls13-18, used in determining PSK modes.
#define SSL_PSK_DHE_KE 0x1
// From draft-ietf-tls-tls13-16, used in determining whether to respond with a
// KeyUpdate.
#define SSL_KEY_UPDATE_NOT_REQUESTED 0
#define SSL_KEY_UPDATE_REQUESTED 1
// 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;
CERT *ssl_cert_new(const SSL_X509_METHOD *x509_method);
CERT *ssl_cert_dup(CERT *cert);
void ssl_cert_clear_certs(CERT *cert);
void ssl_cert_free(CERT *cert);
int ssl_set_cert(CERT *cert, UniquePtr<CRYPTO_BUFFER> buffer);
int ssl_is_key_type_supported(int key_type);
// ssl_compare_public_and_private_key returns one if |pubkey| is the public
// counterpart to |privkey|. Otherwise it returns zero and pushes a helpful
// message on the error queue.
int ssl_compare_public_and_private_key(const EVP_PKEY *pubkey,
const EVP_PKEY *privkey);
int ssl_cert_check_private_key(const CERT *cert, const EVP_PKEY *privkey);
int ssl_get_new_session(SSL_HANDSHAKE *hs, int is_server);
int ssl_encrypt_ticket(SSL *ssl, CBB *out, const SSL_SESSION *session);
int ssl_ctx_rotate_ticket_encryption_key(SSL_CTX *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_SESSION_parse parses an |SSL_SESSION| from |cbs| and advances |cbs| over
// the parsed data.
UniquePtr<SSL_SESSION> SSL_SESSION_parse(CBS *cbs,
const SSL_X509_METHOD *x509_method,
CRYPTO_BUFFER_POOL *pool);
// ssl_session_is_context_valid returns one if |session|'s session ID context
// matches the one set on |ssl| and zero otherwise.
int ssl_session_is_context_valid(const SSL *ssl, const SSL_SESSION *session);
// ssl_session_is_time_valid returns one if |session| is still valid and zero if
// it has expired.
int ssl_session_is_time_valid(const SSL *ssl, const SSL_SESSION *session);
// ssl_session_is_resumable returns one if |session| is resumable for |hs| and
// zero otherwise.
int 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);
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 *ssl,
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(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_cipher_preference_list_free(
struct ssl_cipher_preference_list_st *cipher_list);
// ssl_get_cipher_preferences returns the cipher preference list for TLS 1.2 and
// below.
const struct ssl_cipher_preference_list_st *ssl_get_cipher_preferences(
const SSL *ssl);
void ssl_update_cache(SSL_HANDSHAKE *hs, int mode);
int ssl_send_alert(SSL *ssl, int level, int desc);
bool ssl3_get_message(SSL *ssl, SSLMessage *out);
ssl_open_record_t ssl3_open_handshake(SSL *ssl, size_t *out_consumed,
uint8_t *out_alert, Span<uint8_t> in);
void ssl3_next_message(SSL *ssl);
int ssl3_dispatch_alert(SSL *ssl);
ssl_open_record_t ssl3_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 ssl3_open_change_cipher_spec(SSL *ssl, size_t *out_consumed,
uint8_t *out_alert,
Span<uint8_t> in);
int ssl3_write_app_data(SSL *ssl, bool *out_needs_handshake, const uint8_t *buf,
int len);
bool ssl3_new(SSL *ssl);
void ssl3_free(SSL *ssl);
bool ssl3_init_message(SSL *ssl, CBB *cbb, CBB *body, uint8_t type);
bool ssl3_finish_message(SSL *ssl, CBB *cbb, Array<uint8_t> *out_msg);
bool ssl3_add_message(SSL *ssl, Array<uint8_t> msg);
bool ssl3_add_change_cipher_spec(SSL *ssl);
bool ssl3_add_alert(SSL *ssl, uint8_t level, uint8_t desc);
int ssl3_flush_flight(SSL *ssl);
bool dtls1_init_message(SSL *ssl, CBB *cbb, CBB *body, uint8_t type);
bool dtls1_finish_message(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);
bool dtls1_add_alert(SSL *ssl, uint8_t level, uint8_t desc);
int dtls1_flush_flight(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_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,
const uint8_t *buf, int len);
// dtls1_write_record sends a record. It returns one on success and <= 0 on
// error.
int dtls1_write_record(SSL *ssl, int type, const uint8_t *buf, size_t len,
enum dtls1_use_epoch_t use_epoch);
int dtls1_retransmit_outgoing_messages(SSL *ssl);
bool dtls1_parse_fragment(CBS *cbs, struct hm_header_st *out_hdr,
CBS *out_body);
bool dtls1_check_timeout_num(SSL *ssl);
void dtls1_start_timer(SSL *ssl);
void dtls1_stop_timer(SSL *ssl);
bool dtls1_is_timer_expired(SSL *ssl);
unsigned int dtls1_min_mtu(void);
bool dtls1_new(SSL *ssl);
void dtls1_free(SSL *ssl);
bool dtls1_get_message(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);
int tls1_change_cipher_state(SSL_HANDSHAKE *hs, evp_aead_direction_t direction);
int tls1_generate_master_secret(SSL_HANDSHAKE *hs, uint8_t *out,
Span<const uint8_t> premaster);
// tls1_get_grouplist returns the locally-configured group preference list.
Span<const uint16_t> tls1_get_grouplist(const SSL *ssl);
// tls1_check_group_id returns one if |group_id| is consistent with
// locally-configured group preferences.
int tls1_check_group_id(const SSL *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 one. If none may be
// found, it returns zero.
int tls1_get_shared_group(SSL_HANDSHAKE *hs, uint16_t *out_group_id);
// tls1_set_curves converts the array of |ncurves| NIDs pointed to by |curves|
// into a newly allocated array of TLS group IDs. On success, the function
// returns one and writes the array to |*out_group_ids| and its size to
// |*out_group_ids_len|. Otherwise, it returns zero.
int tls1_set_curves(uint16_t **out_group_ids, size_t *out_group_ids_len,
const int *curves, size_t ncurves);
// tls1_set_curves_list converts the string of curves pointed to by |curves|
// into a newly allocated array of TLS group IDs. On success, the function
// returns one and writes the array to |*out_group_ids| and its size to
// |*out_group_ids_len|. Otherwise, it returns zero.
int tls1_set_curves_list(uint16_t **out_group_ids, size_t *out_group_ids_len,
const char *curves);
// ssl_add_clienthello_tlsext writes ClientHello extensions to |out|. It
// returns one on success and zero on failure. The |header_len| argument is the
// length of the ClientHello written so far and is used to compute the padding
// length. (It does not include the record header.)
int ssl_add_clienthello_tlsext(SSL_HANDSHAKE *hs, CBB *out, size_t header_len);
int ssl_add_serverhello_tlsext(SSL_HANDSHAKE *hs, CBB *out);
int ssl_parse_clienthello_tlsext(SSL_HANDSHAKE *hs,
const SSL_CLIENT_HELLO *client_hello);
int ssl_parse_serverhello_tlsext(SSL_HANDSHAKE *hs, CBS *cbs);
#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 occured that is fatal to the connection.
enum ssl_ticket_aead_result_t ssl_process_ticket(
SSL *ssl, UniquePtr<SSL_SESSION> *out_session, bool *out_renew_ticket,
const uint8_t *ticket, size_t ticket_len, const uint8_t *session_id,
size_t session_id_len);
// 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
// one. Otherwise, it returns zero.
int 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->tlsext_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
// one on success and zero on failure.
int tls1_channel_id_hash(SSL_HANDSHAKE *hs, uint8_t *out, size_t *out_len);
int tls1_record_handshake_hashes_for_channel_id(SSL_HANDSHAKE *hs);
// ssl_do_channel_id_callback checks runs |ssl->ctx->channel_id_cb| if
// necessary. It returns one on success and zero on fatal error. Note that, on
// success, |ssl->tlsext_channel_id_private| may be unset, in which case the
// operation should be retried later.
int ssl_do_channel_id_callback(SSL *ssl);
// ssl_can_write returns one if |ssl| is allowed to write and zero otherwise.
int ssl_can_write(const SSL *ssl);
// ssl_can_read returns one if |ssl| is allowed to read and zero otherwise.
int ssl_can_read(const SSL *ssl);
void ssl_get_current_time(const SSL *ssl, struct OPENSSL_timeval *out_clock);
void ssl_ctx_get_current_time(const SSL_CTX *ctx,
struct OPENSSL_timeval *out_clock);
// 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);
} // namespace bssl
// Opaque C types.
//
// The following types are exported to C code as public typedefs, so they must
// be defined outside of the 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 SSL_X509_METHOD *x509_method;
};
struct ssl_x509_method_st {
// check_client_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.
int (*check_client_CA_list)(STACK_OF(CRYPTO_BUFFER) *names);
// cert_clear frees and NULLs all X509 certificate-related state.
void (*cert_clear)(bssl::CERT *cert);
// cert_free frees all X509-related state.
void (*cert_free)(bssl::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)(bssl::CERT *new_cert, const bssl::CERT *cert);
void (*cert_flush_cached_chain)(bssl::CERT *cert);
// cert_flush_cached_chain drops any cached |X509|-based leaf certificate
// from |cert|.
void (*cert_flush_cached_leaf)(bssl::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
// one on success or zero on error.
int (*session_cache_objects)(SSL_SESSION *session);
// session_dup duplicates any needed fields from |session| to |new_session|.
// It returns one on success or zero on error.
int (*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 one on success or zero on
// error.
int (*session_verify_cert_chain)(SSL_SESSION *session, SSL *ssl,
uint8_t *out_alert);
// hs_flush_cached_ca_names drops any cached |X509_NAME|s from |hs|.
void (*hs_flush_cached_ca_names)(bssl::SSL_HANDSHAKE *hs);
// ssl_new does any neccessary initialisation of |ssl|. It returns one on
// success or zero on error.
int (*ssl_new)(SSL *ssl);
// ssl_free frees anything created by |ssl_new|.
void (*ssl_free)(SSL *ssl);
// ssl_flush_cached_client_CA drops any cached |X509_NAME|s from |ssl|.
void (*ssl_flush_cached_client_CA)(SSL *ssl);
// 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 one. Otherwise, it returns zero.
int (*ssl_auto_chain_if_needed)(SSL *ssl);
// ssl_ctx_new does any neccessary initialisation of |ctx|. It returns one on
// success or zero on error.
int (*ssl_ctx_new)(SSL_CTX *ctx);
// ssl_ctx_free frees anything created by |ssl_ctx_new|.
void (*ssl_ctx_free)(SSL_CTX *ctx);
// ssl_ctx_flush_cached_client_CA drops any cached |X509_NAME|s from |ctx|.
void (*ssl_ctx_flush_cached_client_CA)(SSL_CTX *ssl);
};
// The following types back public C-exposed types which must live in the global
// namespace. We use subclassing so the implementations may be C++ types with
// methods and destructor without polluting the global namespace.
struct ssl_ctx_st : public bssl::SSLContext {};
struct ssl_st : public bssl::SSLConnection {};
#endif // OPENSSL_HEADER_SSL_INTERNAL_H
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