blob: 8fa51e932b51a0f3b180bb7114660d6a55c68e8e [file] [log] [blame]
/* 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) 1998-2002 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. */
#include <openssl/ssl.h>
#include <assert.h>
#include <limits.h>
#include <string.h>
#include <openssl/buf.h>
#include <openssl/bytestring.h>
#include <openssl/err.h>
#include <openssl/evp.h>
#include <openssl/mem.h>
#include <openssl/md5.h>
#include <openssl/nid.h>
#include <openssl/rand.h>
#include <openssl/sha.h>
#include "../crypto/internal.h"
#include "internal.h"
SSL_HANDSHAKE *ssl_handshake_new(SSL *ssl) {
SSL_HANDSHAKE *hs = OPENSSL_malloc(sizeof(SSL_HANDSHAKE));
if (hs == NULL) {
OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
return NULL;
}
OPENSSL_memset(hs, 0, sizeof(SSL_HANDSHAKE));
hs->ssl = ssl;
hs->wait = ssl_hs_ok;
hs->state = SSL_ST_INIT;
if (!SSL_TRANSCRIPT_init(&hs->transcript)) {
ssl_handshake_free(hs);
return NULL;
}
return hs;
}
void ssl_handshake_free(SSL_HANDSHAKE *hs) {
if (hs == NULL) {
return;
}
OPENSSL_cleanse(hs->secret, sizeof(hs->secret));
OPENSSL_cleanse(hs->client_handshake_secret,
sizeof(hs->client_handshake_secret));
OPENSSL_cleanse(hs->server_handshake_secret,
sizeof(hs->server_handshake_secret));
OPENSSL_cleanse(hs->client_traffic_secret_0,
sizeof(hs->client_traffic_secret_0));
OPENSSL_cleanse(hs->server_traffic_secret_0,
sizeof(hs->server_traffic_secret_0));
SSL_ECDH_CTX_cleanup(&hs->ecdh_ctx);
SSL_TRANSCRIPT_cleanup(&hs->transcript);
OPENSSL_free(hs->cookie);
OPENSSL_free(hs->key_share_bytes);
OPENSSL_free(hs->public_key);
SSL_SESSION_free(hs->new_session);
OPENSSL_free(hs->peer_sigalgs);
OPENSSL_free(hs->peer_supported_group_list);
OPENSSL_free(hs->peer_key);
OPENSSL_free(hs->server_params);
OPENSSL_free(hs->peer_psk_identity_hint);
sk_CRYPTO_BUFFER_pop_free(hs->ca_names, CRYPTO_BUFFER_free);
hs->ssl->ctx->x509_method->hs_flush_cached_ca_names(hs);
OPENSSL_free(hs->certificate_types);
if (hs->key_block != NULL) {
OPENSSL_cleanse(hs->key_block, hs->key_block_len);
OPENSSL_free(hs->key_block);
}
OPENSSL_free(hs->hostname);
EVP_PKEY_free(hs->peer_pubkey);
OPENSSL_free(hs);
}
int ssl_check_message_type(SSL *ssl, int type) {
if (ssl->s3->tmp.message_type != type) {
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE);
ERR_add_error_dataf("got type %d, wanted type %d",
ssl->s3->tmp.message_type, type);
return 0;
}
return 1;
}
static int add_record_to_flight(SSL *ssl, uint8_t type, const uint8_t *in,
size_t in_len) {
/* We'll never add a flight while in the process of writing it out. */
assert(ssl->s3->pending_flight_offset == 0);
if (ssl->s3->pending_flight == NULL) {
ssl->s3->pending_flight = BUF_MEM_new();
if (ssl->s3->pending_flight == NULL) {
return 0;
}
}
size_t max_out = in_len + SSL_max_seal_overhead(ssl);
size_t new_cap = ssl->s3->pending_flight->length + max_out;
if (max_out < in_len || new_cap < max_out) {
OPENSSL_PUT_ERROR(SSL, ERR_R_OVERFLOW);
return 0;
}
size_t len;
if (!BUF_MEM_reserve(ssl->s3->pending_flight, new_cap) ||
!tls_seal_record(ssl, (uint8_t *)ssl->s3->pending_flight->data +
ssl->s3->pending_flight->length,
&len, max_out, type, in, in_len)) {
return 0;
}
ssl->s3->pending_flight->length += len;
return 1;
}
int ssl3_init_message(SSL *ssl, CBB *cbb, CBB *body, uint8_t type) {
/* Pick a modest size hint to save most of the |realloc| calls. */
if (!CBB_init(cbb, 64) ||
!CBB_add_u8(cbb, type) ||
!CBB_add_u24_length_prefixed(cbb, body)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
CBB_cleanup(cbb);
return 0;
}
return 1;
}
int ssl3_finish_message(SSL *ssl, CBB *cbb, uint8_t **out_msg,
size_t *out_len) {
if (!CBB_finish(cbb, out_msg, out_len)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return 0;
}
return 1;
}
int ssl3_add_message(SSL *ssl, uint8_t *msg, size_t len) {
/* Add the message to the current flight, splitting into several records if
* needed. */
int ret = 0;
size_t added = 0;
do {
size_t todo = len - added;
if (todo > ssl->max_send_fragment) {
todo = ssl->max_send_fragment;
}
if (!add_record_to_flight(ssl, SSL3_RT_HANDSHAKE, msg + added, todo)) {
goto err;
}
added += todo;
} while (added < len);
ssl_do_msg_callback(ssl, 1 /* write */, SSL3_RT_HANDSHAKE, msg, len);
/* TODO(svaldez): Move this up a layer to fix abstraction for SSL_TRANSCRIPT
* on hs. */
if (ssl->s3->hs != NULL &&
!SSL_TRANSCRIPT_update(&ssl->s3->hs->transcript, msg, len)) {
goto err;
}
ret = 1;
err:
OPENSSL_free(msg);
return ret;
}
int ssl3_add_change_cipher_spec(SSL *ssl) {
static const uint8_t kChangeCipherSpec[1] = {SSL3_MT_CCS};
if (!add_record_to_flight(ssl, SSL3_RT_CHANGE_CIPHER_SPEC, kChangeCipherSpec,
sizeof(kChangeCipherSpec))) {
return 0;
}
ssl_do_msg_callback(ssl, 1 /* write */, SSL3_RT_CHANGE_CIPHER_SPEC,
kChangeCipherSpec, sizeof(kChangeCipherSpec));
return 1;
}
int ssl3_add_alert(SSL *ssl, uint8_t level, uint8_t desc) {
uint8_t alert[2] = {level, desc};
if (!add_record_to_flight(ssl, SSL3_RT_ALERT, alert, sizeof(alert))) {
return 0;
}
ssl_do_msg_callback(ssl, 1 /* write */, SSL3_RT_ALERT, alert, sizeof(alert));
ssl_do_info_callback(ssl, SSL_CB_WRITE_ALERT, ((int)level << 8) | desc);
return 1;
}
int ssl_add_message_cbb(SSL *ssl, CBB *cbb) {
uint8_t *msg;
size_t len;
if (!ssl->method->finish_message(ssl, cbb, &msg, &len) ||
!ssl->method->add_message(ssl, msg, len)) {
return 0;
}
return 1;
}
int ssl3_flush_flight(SSL *ssl) {
if (ssl->s3->pending_flight == NULL) {
return 1;
}
if (ssl->s3->pending_flight->length > 0xffffffff ||
ssl->s3->pending_flight->length > INT_MAX) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return -1;
}
/* The handshake flight buffer is mutually exclusive with application data.
*
* TODO(davidben): This will not be true when closure alerts use this. */
if (ssl_write_buffer_is_pending(ssl)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return -1;
}
/* Write the pending flight. */
while (ssl->s3->pending_flight_offset < ssl->s3->pending_flight->length) {
int ret = BIO_write(
ssl->wbio,
ssl->s3->pending_flight->data + ssl->s3->pending_flight_offset,
ssl->s3->pending_flight->length - ssl->s3->pending_flight_offset);
if (ret <= 0) {
ssl->rwstate = SSL_WRITING;
return ret;
}
ssl->s3->pending_flight_offset += ret;
}
if (BIO_flush(ssl->wbio) <= 0) {
ssl->rwstate = SSL_WRITING;
return -1;
}
BUF_MEM_free(ssl->s3->pending_flight);
ssl->s3->pending_flight = NULL;
ssl->s3->pending_flight_offset = 0;
return 1;
}
int ssl3_send_finished(SSL_HANDSHAKE *hs) {
SSL *const ssl = hs->ssl;
const SSL_SESSION *session = SSL_get_session(ssl);
uint8_t finished[EVP_MAX_MD_SIZE];
size_t finished_len;
if (!SSL_TRANSCRIPT_finish_mac(&hs->transcript, finished, &finished_len,
session, ssl->server,
ssl3_protocol_version(ssl))) {
return 0;
}
/* Log the master secret, if logging is enabled. */
if (!ssl_log_secret(ssl, "CLIENT_RANDOM",
session->master_key,
session->master_key_length)) {
return 0;
}
/* Copy the Finished so we can use it for renegotiation checks. */
if (ssl->version != SSL3_VERSION) {
if (finished_len > sizeof(ssl->s3->previous_client_finished) ||
finished_len > sizeof(ssl->s3->previous_server_finished)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return -1;
}
if (ssl->server) {
OPENSSL_memcpy(ssl->s3->previous_server_finished, finished, finished_len);
ssl->s3->previous_server_finished_len = finished_len;
} else {
OPENSSL_memcpy(ssl->s3->previous_client_finished, finished, finished_len);
ssl->s3->previous_client_finished_len = finished_len;
}
}
CBB cbb, body;
if (!ssl->method->init_message(ssl, &cbb, &body, SSL3_MT_FINISHED) ||
!CBB_add_bytes(&body, finished, finished_len) ||
!ssl_add_message_cbb(ssl, &cbb)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
CBB_cleanup(&cbb);
return -1;
}
return 1;
}
int ssl3_get_finished(SSL_HANDSHAKE *hs) {
SSL *const ssl = hs->ssl;
int ret = ssl->method->ssl_get_message(ssl);
if (ret <= 0) {
return ret;
}
if (!ssl_check_message_type(ssl, SSL3_MT_FINISHED)) {
return -1;
}
/* Snapshot the finished hash before incorporating the new message. */
uint8_t finished[EVP_MAX_MD_SIZE];
size_t finished_len;
if (!SSL_TRANSCRIPT_finish_mac(&hs->transcript, finished, &finished_len,
SSL_get_session(ssl), !ssl->server,
ssl3_protocol_version(ssl)) ||
!ssl_hash_current_message(hs)) {
return -1;
}
int finished_ok = ssl->init_num == finished_len &&
CRYPTO_memcmp(ssl->init_msg, finished, finished_len) == 0;
#if defined(BORINGSSL_UNSAFE_FUZZER_MODE)
finished_ok = 1;
#endif
if (!finished_ok) {
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECRYPT_ERROR);
OPENSSL_PUT_ERROR(SSL, SSL_R_DIGEST_CHECK_FAILED);
return -1;
}
/* Copy the Finished so we can use it for renegotiation checks. */
if (ssl->version != SSL3_VERSION) {
if (finished_len > sizeof(ssl->s3->previous_client_finished) ||
finished_len > sizeof(ssl->s3->previous_server_finished)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return -1;
}
if (ssl->server) {
OPENSSL_memcpy(ssl->s3->previous_client_finished, finished, finished_len);
ssl->s3->previous_client_finished_len = finished_len;
} else {
OPENSSL_memcpy(ssl->s3->previous_server_finished, finished, finished_len);
ssl->s3->previous_server_finished_len = finished_len;
}
}
return 1;
}
int ssl3_output_cert_chain(SSL *ssl) {
CBB cbb, body;
if (!ssl->method->init_message(ssl, &cbb, &body, SSL3_MT_CERTIFICATE) ||
!ssl_add_cert_chain(ssl, &body) ||
!ssl_add_message_cbb(ssl, &cbb)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
CBB_cleanup(&cbb);
return 0;
}
return 1;
}
size_t ssl_max_handshake_message_len(const SSL *ssl) {
/* kMaxMessageLen is the default maximum message size for handshakes which do
* not accept peer certificate chains. */
static const size_t kMaxMessageLen = 16384;
if (SSL_in_init(ssl)) {
if ((!ssl->server || (ssl->verify_mode & SSL_VERIFY_PEER)) &&
kMaxMessageLen < ssl->max_cert_list) {
return ssl->max_cert_list;
}
return kMaxMessageLen;
}
if (ssl3_protocol_version(ssl) < TLS1_3_VERSION) {
/* In TLS 1.2 and below, the largest acceptable post-handshake message is
* a HelloRequest. */
return 0;
}
if (ssl->server) {
/* The largest acceptable post-handshake message for a server is a
* KeyUpdate. We will never initiate post-handshake auth. */
return 1;
}
/* Clients must accept NewSessionTicket and CertificateRequest, so allow the
* default size. */
return kMaxMessageLen;
}
static int extend_handshake_buffer(SSL *ssl, size_t length) {
if (!BUF_MEM_reserve(ssl->init_buf, length)) {
return -1;
}
while (ssl->init_buf->length < length) {
int ret = ssl3_read_handshake_bytes(
ssl, (uint8_t *)ssl->init_buf->data + ssl->init_buf->length,
length - ssl->init_buf->length);
if (ret <= 0) {
return ret;
}
ssl->init_buf->length += (size_t)ret;
}
return 1;
}
static int read_v2_client_hello(SSL *ssl) {
/* Read the first 5 bytes, the size of the TLS record header. This is
* sufficient to detect a V2ClientHello and ensures that we never read beyond
* the first record. */
int ret = ssl_read_buffer_extend_to(ssl, SSL3_RT_HEADER_LENGTH);
if (ret <= 0) {
return ret;
}
const uint8_t *p = ssl_read_buffer(ssl);
/* Some dedicated error codes for protocol mixups should the application wish
* to interpret them differently. (These do not overlap with ClientHello or
* V2ClientHello.) */
if (strncmp("GET ", (const char *)p, 4) == 0 ||
strncmp("POST ", (const char *)p, 5) == 0 ||
strncmp("HEAD ", (const char *)p, 5) == 0 ||
strncmp("PUT ", (const char *)p, 4) == 0) {
OPENSSL_PUT_ERROR(SSL, SSL_R_HTTP_REQUEST);
return -1;
}
if (strncmp("CONNE", (const char *)p, 5) == 0) {
OPENSSL_PUT_ERROR(SSL, SSL_R_HTTPS_PROXY_REQUEST);
return -1;
}
if ((p[0] & 0x80) == 0 || p[2] != SSL2_MT_CLIENT_HELLO ||
p[3] != SSL3_VERSION_MAJOR) {
/* Not a V2ClientHello. */
return 1;
}
/* Determine the length of the V2ClientHello. */
size_t msg_length = ((p[0] & 0x7f) << 8) | p[1];
if (msg_length > (1024 * 4)) {
OPENSSL_PUT_ERROR(SSL, SSL_R_RECORD_TOO_LARGE);
return -1;
}
if (msg_length < SSL3_RT_HEADER_LENGTH - 2) {
/* Reject lengths that are too short early. We have already read
* |SSL3_RT_HEADER_LENGTH| bytes, so we should not attempt to process an
* (invalid) V2ClientHello which would be shorter than that. */
OPENSSL_PUT_ERROR(SSL, SSL_R_RECORD_LENGTH_MISMATCH);
return -1;
}
/* Read the remainder of the V2ClientHello. */
ret = ssl_read_buffer_extend_to(ssl, 2 + msg_length);
if (ret <= 0) {
return ret;
}
CBS v2_client_hello;
CBS_init(&v2_client_hello, ssl_read_buffer(ssl) + 2, msg_length);
/* The V2ClientHello without the length is incorporated into the handshake
* hash. This is only ever called at the start of the handshake, so hs is
* guaranteed to be non-NULL. */
if (!SSL_TRANSCRIPT_update(&ssl->s3->hs->transcript,
CBS_data(&v2_client_hello),
CBS_len(&v2_client_hello))) {
return -1;
}
ssl_do_msg_callback(ssl, 0 /* read */, 0 /* V2ClientHello */,
CBS_data(&v2_client_hello), CBS_len(&v2_client_hello));
uint8_t msg_type;
uint16_t version, cipher_spec_length, session_id_length, challenge_length;
CBS cipher_specs, session_id, challenge;
if (!CBS_get_u8(&v2_client_hello, &msg_type) ||
!CBS_get_u16(&v2_client_hello, &version) ||
!CBS_get_u16(&v2_client_hello, &cipher_spec_length) ||
!CBS_get_u16(&v2_client_hello, &session_id_length) ||
!CBS_get_u16(&v2_client_hello, &challenge_length) ||
!CBS_get_bytes(&v2_client_hello, &cipher_specs, cipher_spec_length) ||
!CBS_get_bytes(&v2_client_hello, &session_id, session_id_length) ||
!CBS_get_bytes(&v2_client_hello, &challenge, challenge_length) ||
CBS_len(&v2_client_hello) != 0) {
OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
return -1;
}
/* msg_type has already been checked. */
assert(msg_type == SSL2_MT_CLIENT_HELLO);
/* The client_random is the V2ClientHello challenge. Truncate or
* left-pad with zeros as needed. */
size_t rand_len = CBS_len(&challenge);
if (rand_len > SSL3_RANDOM_SIZE) {
rand_len = SSL3_RANDOM_SIZE;
}
uint8_t random[SSL3_RANDOM_SIZE];
OPENSSL_memset(random, 0, SSL3_RANDOM_SIZE);
OPENSSL_memcpy(random + (SSL3_RANDOM_SIZE - rand_len), CBS_data(&challenge),
rand_len);
/* Write out an equivalent SSLv3 ClientHello. */
size_t max_v3_client_hello = SSL3_HM_HEADER_LENGTH + 2 /* version */ +
SSL3_RANDOM_SIZE + 1 /* session ID length */ +
2 /* cipher list length */ +
CBS_len(&cipher_specs) / 3 * 2 +
1 /* compression length */ + 1 /* compression */;
CBB client_hello, hello_body, cipher_suites;
CBB_zero(&client_hello);
if (!BUF_MEM_reserve(ssl->init_buf, max_v3_client_hello) ||
!CBB_init_fixed(&client_hello, (uint8_t *)ssl->init_buf->data,
ssl->init_buf->max) ||
!CBB_add_u8(&client_hello, SSL3_MT_CLIENT_HELLO) ||
!CBB_add_u24_length_prefixed(&client_hello, &hello_body) ||
!CBB_add_u16(&hello_body, version) ||
!CBB_add_bytes(&hello_body, random, SSL3_RANDOM_SIZE) ||
/* No session id. */
!CBB_add_u8(&hello_body, 0) ||
!CBB_add_u16_length_prefixed(&hello_body, &cipher_suites)) {
CBB_cleanup(&client_hello);
OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
return -1;
}
/* Copy the cipher suites. */
while (CBS_len(&cipher_specs) > 0) {
uint32_t cipher_spec;
if (!CBS_get_u24(&cipher_specs, &cipher_spec)) {
CBB_cleanup(&client_hello);
OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
return -1;
}
/* Skip SSLv2 ciphers. */
if ((cipher_spec & 0xff0000) != 0) {
continue;
}
if (!CBB_add_u16(&cipher_suites, cipher_spec)) {
CBB_cleanup(&client_hello);
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return -1;
}
}
/* Add the null compression scheme and finish. */
if (!CBB_add_u8(&hello_body, 1) || !CBB_add_u8(&hello_body, 0) ||
!CBB_finish(&client_hello, NULL, &ssl->init_buf->length)) {
CBB_cleanup(&client_hello);
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return -1;
}
/* Consume and discard the V2ClientHello. */
ssl_read_buffer_consume(ssl, 2 + msg_length);
ssl_read_buffer_discard(ssl);
ssl->s3->is_v2_hello = 1;
/* This is the first message, so hs must be non-NULL. */
ssl->s3->hs->v2_clienthello = 1;
return 1;
}
int ssl3_get_message(SSL *ssl) {
/* Re-create the handshake buffer if needed. */
if (ssl->init_buf == NULL) {
ssl->init_buf = BUF_MEM_new();
if (ssl->init_buf == NULL) {
return -1;
}
}
if (ssl->server && !ssl->s3->v2_hello_done) {
/* Bypass the record layer for the first message to handle V2ClientHello. */
int ret = read_v2_client_hello(ssl);
if (ret <= 0) {
return ret;
}
ssl->s3->v2_hello_done = 1;
}
if (ssl->s3->tmp.reuse_message) {
/* There must be a current message. */
assert(ssl->init_msg != NULL);
ssl->s3->tmp.reuse_message = 0;
} else {
ssl3_release_current_message(ssl, 0 /* don't free buffer */);
}
/* Read the message header, if we haven't yet. */
int ret = extend_handshake_buffer(ssl, SSL3_HM_HEADER_LENGTH);
if (ret <= 0) {
return ret;
}
/* Parse out the length. Cap it so the peer cannot force us to buffer up to
* 2^24 bytes. */
const uint8_t *p = (uint8_t *)ssl->init_buf->data;
size_t msg_len = (((uint32_t)p[1]) << 16) | (((uint32_t)p[2]) << 8) | p[3];
if (msg_len > ssl_max_handshake_message_len(ssl)) {
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
OPENSSL_PUT_ERROR(SSL, SSL_R_EXCESSIVE_MESSAGE_SIZE);
return -1;
}
/* Read the message body, if we haven't yet. */
ret = extend_handshake_buffer(ssl, SSL3_HM_HEADER_LENGTH + msg_len);
if (ret <= 0) {
return ret;
}
/* We have now received a complete message. */
ssl_do_msg_callback(ssl, 0 /* read */, SSL3_RT_HANDSHAKE, ssl->init_buf->data,
ssl->init_buf->length);
ssl->s3->tmp.message_type = ((const uint8_t *)ssl->init_buf->data)[0];
ssl->init_msg = (uint8_t*)ssl->init_buf->data + SSL3_HM_HEADER_LENGTH;
ssl->init_num = ssl->init_buf->length - SSL3_HM_HEADER_LENGTH;
return 1;
}
void ssl3_get_current_message(const SSL *ssl, CBS *out) {
CBS_init(out, (uint8_t *)ssl->init_buf->data, ssl->init_buf->length);
}
int ssl_hash_current_message(SSL_HANDSHAKE *hs) {
/* V2ClientHellos are hashed implicitly. */
if (hs->ssl->s3->is_v2_hello) {
return 1;
}
CBS cbs;
hs->ssl->method->get_current_message(hs->ssl, &cbs);
return SSL_TRANSCRIPT_update(&hs->transcript, CBS_data(&cbs), CBS_len(&cbs));
}
void ssl3_release_current_message(SSL *ssl, int free_buffer) {
if (ssl->init_msg != NULL) {
/* |init_buf| never contains data beyond the current message. */
assert(SSL3_HM_HEADER_LENGTH + ssl->init_num == ssl->init_buf->length);
/* Clear the current message. */
ssl->init_msg = NULL;
ssl->init_num = 0;
ssl->init_buf->length = 0;
ssl->s3->is_v2_hello = 0;
}
if (free_buffer) {
BUF_MEM_free(ssl->init_buf);
ssl->init_buf = NULL;
}
}
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) {
/* Reset everything. */
for (size_t i = 0; i < num_ext_types; i++) {
*ext_types[i].out_present = 0;
CBS_init(ext_types[i].out_data, NULL, 0);
}
CBS copy = *cbs;
while (CBS_len(&copy) != 0) {
uint16_t type;
CBS data;
if (!CBS_get_u16(&copy, &type) ||
!CBS_get_u16_length_prefixed(&copy, &data)) {
OPENSSL_PUT_ERROR(SSL, SSL_R_PARSE_TLSEXT);
*out_alert = SSL_AD_DECODE_ERROR;
return 0;
}
const SSL_EXTENSION_TYPE *ext_type = NULL;
for (size_t i = 0; i < num_ext_types; i++) {
if (type == ext_types[i].type) {
ext_type = &ext_types[i];
break;
}
}
if (ext_type == NULL) {
if (ignore_unknown) {
continue;
}
OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_EXTENSION);
*out_alert = SSL_AD_UNSUPPORTED_EXTENSION;
return 0;
}
/* Duplicate ext_types are forbidden. */
if (*ext_type->out_present) {
OPENSSL_PUT_ERROR(SSL, SSL_R_DUPLICATE_EXTENSION);
*out_alert = SSL_AD_ILLEGAL_PARAMETER;
return 0;
}
*ext_type->out_present = 1;
*ext_type->out_data = data;
}
return 1;
}