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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.
- *
- * Portions of the attached software ("Contribution") are developed by
- * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project.
- *
- * The Contribution is licensed pursuant to the OpenSSL open source
- * license provided above.
- *
- * ECC cipher suite support in OpenSSL originally written by
- * Vipul Gupta and Sumit Gupta of Sun Microsystems Laboratories.
- *
- */
- /* ====================================================================
- * 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.
- */
-
- #include <openssl/ssl.h>
-
- #include <assert.h>
- #include <limits.h>
- #include <string.h>
-
- #include <utility>
-
- #include <openssl/aead.h>
- #include <openssl/bn.h>
- #include <openssl/buf.h>
- #include <openssl/bytestring.h>
- #include <openssl/ec_key.h>
- #include <openssl/ecdsa.h>
- #include <openssl/err.h>
- #include <openssl/evp.h>
- #include <openssl/md5.h>
- #include <openssl/mem.h>
- #include <openssl/rand.h>
-
- #include "../crypto/internal.h"
- #include "internal.h"
-
-
- namespace bssl {
-
- enum ssl_client_hs_state_t {
- state_start_connect = 0,
- state_enter_early_data,
- state_read_hello_verify_request,
- state_read_server_hello,
- state_tls13,
- state_read_server_certificate,
- state_read_certificate_status,
- state_verify_server_certificate,
- state_read_server_key_exchange,
- state_read_certificate_request,
- state_read_server_hello_done,
- state_send_client_certificate,
- state_send_client_key_exchange,
- state_send_client_certificate_verify,
- state_send_client_finished,
- state_finish_flight,
- state_read_session_ticket,
- state_process_change_cipher_spec,
- state_read_server_finished,
- state_finish_client_handshake,
- state_done,
- };
-
- // ssl_get_client_disabled sets |*out_mask_a| and |*out_mask_k| to masks of
- // disabled algorithms.
- static void ssl_get_client_disabled(SSL_HANDSHAKE *hs, uint32_t *out_mask_a,
- uint32_t *out_mask_k) {
- *out_mask_a = 0;
- *out_mask_k = 0;
-
- // PSK requires a client callback.
- if (hs->config->psk_client_callback == NULL) {
- *out_mask_a |= SSL_aPSK;
- *out_mask_k |= SSL_kPSK;
- }
- }
-
- static int ssl_write_client_cipher_list(SSL_HANDSHAKE *hs, CBB *out) {
- SSL *const ssl = hs->ssl;
- uint32_t mask_a, mask_k;
- ssl_get_client_disabled(hs, &mask_a, &mask_k);
-
- CBB child;
- if (!CBB_add_u16_length_prefixed(out, &child)) {
- return 0;
- }
-
- // Add a fake cipher suite. See draft-davidben-tls-grease-01.
- if (ssl->ctx->grease_enabled &&
- !CBB_add_u16(&child, ssl_get_grease_value(hs, ssl_grease_cipher))) {
- return 0;
- }
-
- // Add TLS 1.3 ciphers. Order ChaCha20-Poly1305 relative to AES-GCM based on
- // hardware support.
- if (hs->max_version >= TLS1_3_VERSION) {
- if (!EVP_has_aes_hardware() &&
- !CBB_add_u16(&child, TLS1_CK_CHACHA20_POLY1305_SHA256 & 0xffff)) {
- return 0;
- }
- if (!CBB_add_u16(&child, TLS1_CK_AES_128_GCM_SHA256 & 0xffff) ||
- !CBB_add_u16(&child, TLS1_CK_AES_256_GCM_SHA384 & 0xffff)) {
- return 0;
- }
- if (EVP_has_aes_hardware() &&
- !CBB_add_u16(&child, TLS1_CK_CHACHA20_POLY1305_SHA256 & 0xffff)) {
- return 0;
- }
- }
-
- if (hs->min_version < TLS1_3_VERSION) {
- int any_enabled = 0;
- for (const SSL_CIPHER *cipher : SSL_get_ciphers(ssl)) {
- // Skip disabled ciphers
- if ((cipher->algorithm_mkey & mask_k) ||
- (cipher->algorithm_auth & mask_a)) {
- continue;
- }
- if (SSL_CIPHER_get_min_version(cipher) > hs->max_version ||
- SSL_CIPHER_get_max_version(cipher) < hs->min_version) {
- continue;
- }
- any_enabled = 1;
- if (!CBB_add_u16(&child, ssl_cipher_get_value(cipher))) {
- return 0;
- }
- }
-
- // If all ciphers were disabled, return the error to the caller.
- if (!any_enabled && hs->max_version < TLS1_3_VERSION) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_NO_CIPHERS_AVAILABLE);
- return 0;
- }
- }
-
- if (ssl->mode & SSL_MODE_SEND_FALLBACK_SCSV) {
- if (!CBB_add_u16(&child, SSL3_CK_FALLBACK_SCSV & 0xffff)) {
- return 0;
- }
- }
-
- return CBB_flush(out);
- }
-
- int ssl_write_client_hello(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
- ScopedCBB cbb;
- CBB body;
- if (!ssl->method->init_message(ssl, cbb.get(), &body, SSL3_MT_CLIENT_HELLO)) {
- return 0;
- }
-
- CBB child;
- if (!CBB_add_u16(&body, hs->client_version) ||
- !CBB_add_bytes(&body, ssl->s3->client_random, SSL3_RANDOM_SIZE) ||
- !CBB_add_u8_length_prefixed(&body, &child)) {
- return 0;
- }
-
- // Do not send a session ID on renegotiation.
- if (!ssl->s3->initial_handshake_complete &&
- !CBB_add_bytes(&child, hs->session_id, hs->session_id_len)) {
- return 0;
- }
-
- if (SSL_is_dtls(ssl)) {
- if (!CBB_add_u8_length_prefixed(&body, &child) ||
- !CBB_add_bytes(&child, ssl->d1->cookie, ssl->d1->cookie_len)) {
- return 0;
- }
- }
-
- size_t header_len =
- SSL_is_dtls(ssl) ? DTLS1_HM_HEADER_LENGTH : SSL3_HM_HEADER_LENGTH;
- if (!ssl_write_client_cipher_list(hs, &body) ||
- !CBB_add_u8(&body, 1 /* one compression method */) ||
- !CBB_add_u8(&body, 0 /* null compression */) ||
- !ssl_add_clienthello_tlsext(hs, &body, header_len + CBB_len(&body))) {
- return 0;
- }
-
- Array<uint8_t> msg;
- if (!ssl->method->finish_message(ssl, cbb.get(), &msg)) {
- return 0;
- }
-
- // Now that the length prefixes have been computed, fill in the placeholder
- // PSK binder.
- if (hs->needs_psk_binder &&
- !tls13_write_psk_binder(hs, msg.data(), msg.size())) {
- return 0;
- }
-
- return ssl->method->add_message(ssl, std::move(msg));
- }
-
- static bool parse_supported_versions(SSL_HANDSHAKE *hs, uint16_t *version,
- const CBS *in) {
- // If the outer version is not TLS 1.2, or there is no extensions block, use
- // the outer version.
- if (*version != TLS1_2_VERSION || CBS_len(in) == 0) {
- return true;
- }
-
- SSL *const ssl = hs->ssl;
- CBS copy = *in, extensions;
- if (!CBS_get_u16_length_prefixed(©, &extensions) ||
- CBS_len(©) != 0) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return false;
- }
-
- bool have_supported_versions;
- CBS supported_versions;
- const SSL_EXTENSION_TYPE ext_types[] = {
- {TLSEXT_TYPE_supported_versions, &have_supported_versions,
- &supported_versions},
- };
-
- uint8_t alert = SSL_AD_DECODE_ERROR;
- if (!ssl_parse_extensions(&extensions, &alert, ext_types,
- OPENSSL_ARRAY_SIZE(ext_types),
- 1 /* ignore unknown */)) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
- return false;
- }
-
- // Override the outer version with the extension, if present.
- if (have_supported_versions &&
- (!CBS_get_u16(&supported_versions, version) ||
- CBS_len(&supported_versions) != 0)) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return false;
- }
-
- return true;
- }
-
- static enum ssl_hs_wait_t do_start_connect(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
-
- ssl_do_info_callback(ssl, SSL_CB_HANDSHAKE_START, 1);
- // |session_reused| must be reset in case this is a renegotiation.
- ssl->s3->session_reused = false;
-
- // Freeze the version range.
- if (!ssl_get_version_range(hs, &hs->min_version, &hs->max_version)) {
- return ssl_hs_error;
- }
-
- // Always advertise the ClientHello version from the original maximum version,
- // even on renegotiation. The static RSA key exchange uses this field, and
- // some servers fail when it changes across handshakes.
- if (SSL_is_dtls(hs->ssl)) {
- hs->client_version =
- hs->max_version >= TLS1_2_VERSION ? DTLS1_2_VERSION : DTLS1_VERSION;
- } else {
- hs->client_version =
- hs->max_version >= TLS1_2_VERSION ? TLS1_2_VERSION : hs->max_version;
- }
-
- // If the configured session has expired or was created at a disabled
- // version, drop it.
- if (ssl->session != NULL) {
- if (ssl->session->is_server ||
- !ssl_supports_version(hs, ssl->session->ssl_version) ||
- (ssl->session->session_id_length == 0 &&
- ssl->session->ticket.empty()) ||
- ssl->session->not_resumable ||
- !ssl_session_is_time_valid(ssl, ssl->session.get())) {
- ssl_set_session(ssl, NULL);
- }
- }
-
- if (!RAND_bytes(ssl->s3->client_random, sizeof(ssl->s3->client_random))) {
- return ssl_hs_error;
- }
-
- // Initialize a random session ID for the experimental TLS 1.3 variant
- // requiring a session id.
- if (ssl->session != nullptr &&
- !ssl->s3->initial_handshake_complete &&
- ssl->session->session_id_length > 0) {
- hs->session_id_len = ssl->session->session_id_length;
- OPENSSL_memcpy(hs->session_id, ssl->session->session_id,
- hs->session_id_len);
- } else if (hs->max_version >= TLS1_3_VERSION) {
- hs->session_id_len = sizeof(hs->session_id);
- if (!RAND_bytes(hs->session_id, hs->session_id_len)) {
- return ssl_hs_error;
- }
- }
-
- if (!ssl_write_client_hello(hs)) {
- return ssl_hs_error;
- }
-
- hs->state = state_enter_early_data;
- return ssl_hs_flush;
- }
-
- static enum ssl_hs_wait_t do_enter_early_data(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
-
- if (SSL_is_dtls(ssl)) {
- hs->state = state_read_hello_verify_request;
- return ssl_hs_ok;
- }
-
- if (!hs->early_data_offered) {
- hs->state = state_read_server_hello;
- return ssl_hs_ok;
- }
-
- ssl->s3->aead_write_ctx->SetVersionIfNullCipher(ssl->session->ssl_version);
- if (!ssl->method->add_change_cipher_spec(ssl)) {
- return ssl_hs_error;
- }
-
- if (!tls13_init_early_key_schedule(hs, ssl->session->master_key,
- ssl->session->master_key_length) ||
- !tls13_derive_early_secrets(hs) ||
- !tls13_set_traffic_key(ssl, evp_aead_seal, hs->early_traffic_secret,
- hs->hash_len)) {
- return ssl_hs_error;
- }
-
- // Stash the early data session, so connection properties may be queried out
- // of it.
- hs->in_early_data = true;
- hs->early_session = UpRef(ssl->session);
- hs->can_early_write = true;
-
- hs->state = state_read_server_hello;
- return ssl_hs_early_return;
- }
-
- static enum ssl_hs_wait_t do_read_hello_verify_request(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
-
- assert(SSL_is_dtls(ssl));
-
- SSLMessage msg;
- if (!ssl->method->get_message(ssl, &msg)) {
- return ssl_hs_read_message;
- }
-
- if (msg.type != DTLS1_MT_HELLO_VERIFY_REQUEST) {
- hs->state = state_read_server_hello;
- return ssl_hs_ok;
- }
-
- CBS hello_verify_request = msg.body, cookie;
- uint16_t server_version;
- if (!CBS_get_u16(&hello_verify_request, &server_version) ||
- !CBS_get_u8_length_prefixed(&hello_verify_request, &cookie) ||
- CBS_len(&cookie) > sizeof(ssl->d1->cookie) ||
- CBS_len(&hello_verify_request) != 0) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return ssl_hs_error;
- }
-
- OPENSSL_memcpy(ssl->d1->cookie, CBS_data(&cookie), CBS_len(&cookie));
- ssl->d1->cookie_len = CBS_len(&cookie);
-
- ssl->method->next_message(ssl);
-
- // DTLS resets the handshake buffer after HelloVerifyRequest.
- if (!hs->transcript.Init()) {
- return ssl_hs_error;
- }
-
- if (!ssl_write_client_hello(hs)) {
- return ssl_hs_error;
- }
-
- hs->state = state_read_server_hello;
- return ssl_hs_flush;
- }
-
- static enum ssl_hs_wait_t do_read_server_hello(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
- SSLMessage msg;
- if (!ssl->method->get_message(ssl, &msg)) {
- return ssl_hs_read_server_hello;
- }
-
- if (!ssl_check_message_type(ssl, msg, SSL3_MT_SERVER_HELLO)) {
- return ssl_hs_error;
- }
-
- CBS server_hello = msg.body, server_random, session_id;
- uint16_t server_version, cipher_suite;
- uint8_t compression_method;
- if (!CBS_get_u16(&server_hello, &server_version) ||
- !CBS_get_bytes(&server_hello, &server_random, SSL3_RANDOM_SIZE) ||
- !CBS_get_u8_length_prefixed(&server_hello, &session_id) ||
- CBS_len(&session_id) > SSL3_SESSION_ID_SIZE ||
- !CBS_get_u16(&server_hello, &cipher_suite) ||
- !CBS_get_u8(&server_hello, &compression_method)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return ssl_hs_error;
- }
-
- // Use the supported_versions extension if applicable.
- if (!parse_supported_versions(hs, &server_version, &server_hello)) {
- return ssl_hs_error;
- }
-
- if (!ssl_supports_version(hs, server_version)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_UNSUPPORTED_PROTOCOL);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_PROTOCOL_VERSION);
- return ssl_hs_error;
- }
-
- assert(ssl->s3->have_version == ssl->s3->initial_handshake_complete);
- if (!ssl->s3->have_version) {
- ssl->version = server_version;
- // At this point, the connection's version is known and ssl->version is
- // fixed. Begin enforcing the record-layer version.
- ssl->s3->have_version = true;
- ssl->s3->aead_write_ctx->SetVersionIfNullCipher(ssl->version);
- } else if (server_version != ssl->version) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_SSL_VERSION);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_PROTOCOL_VERSION);
- return ssl_hs_error;
- }
-
- if (ssl_protocol_version(ssl) >= TLS1_3_VERSION) {
- hs->state = state_tls13;
- return ssl_hs_ok;
- }
-
- // Clear some TLS 1.3 state that no longer needs to be retained.
- hs->key_share.reset();
- hs->key_share_bytes.Reset();
-
- // A TLS 1.2 server would not know to skip the early data we offered. Report
- // an error code sooner. The caller may use this error code to implement the
- // fallback described in draft-ietf-tls-tls13-18 appendix C.3.
- if (hs->early_data_offered) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_VERSION_ON_EARLY_DATA);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_PROTOCOL_VERSION);
- return ssl_hs_error;
- }
-
- // Copy over the server random.
- OPENSSL_memcpy(ssl->s3->server_random, CBS_data(&server_random),
- SSL3_RANDOM_SIZE);
-
- // Measure, but do not enforce, the TLS 1.3 anti-downgrade feature, with a
- // different value.
- //
- // For draft TLS 1.3 versions, it is not safe to deploy this feature. However,
- // some TLS terminators are non-compliant and copy the origin server's value,
- // so we wish to measure eventual compatibility impact.
- if (!ssl->s3->initial_handshake_complete &&
- hs->max_version >= TLS1_3_VERSION &&
- OPENSSL_memcmp(ssl->s3->server_random + SSL3_RANDOM_SIZE -
- sizeof(kDraftDowngradeRandom),
- kDraftDowngradeRandom,
- sizeof(kDraftDowngradeRandom)) == 0) {
- ssl->s3->draft_downgrade = true;
- }
-
- if (!ssl->s3->initial_handshake_complete && ssl->session != NULL &&
- ssl->session->session_id_length != 0 &&
- CBS_mem_equal(&session_id, ssl->session->session_id,
- ssl->session->session_id_length)) {
- ssl->s3->session_reused = true;
- } else {
- // The server may also have echoed back the TLS 1.3 compatibility mode
- // session ID. As we know this is not a session the server knows about, any
- // server resuming it is in error. Reject the first connection
- // deterministicly, rather than installing an invalid session into the
- // session cache. https://crbug.com/796910
- if (hs->session_id_len != 0 &&
- CBS_mem_equal(&session_id, hs->session_id, hs->session_id_len)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_SERVER_ECHOED_INVALID_SESSION_ID);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
- return ssl_hs_error;
- }
-
- // The session wasn't resumed. Create a fresh SSL_SESSION to
- // fill out.
- ssl_set_session(ssl, NULL);
- if (!ssl_get_new_session(hs, 0 /* client */)) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
- return ssl_hs_error;
- }
- // Note: session_id could be empty.
- hs->new_session->session_id_length = CBS_len(&session_id);
- OPENSSL_memcpy(hs->new_session->session_id, CBS_data(&session_id),
- CBS_len(&session_id));
- }
-
- const SSL_CIPHER *cipher = SSL_get_cipher_by_value(cipher_suite);
- if (cipher == NULL) {
- // unknown cipher
- OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_CIPHER_RETURNED);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
- return ssl_hs_error;
- }
-
- // The cipher must be allowed in the selected version and enabled.
- uint32_t mask_a, mask_k;
- ssl_get_client_disabled(hs, &mask_a, &mask_k);
- if ((cipher->algorithm_mkey & mask_k) || (cipher->algorithm_auth & mask_a) ||
- SSL_CIPHER_get_min_version(cipher) > ssl_protocol_version(ssl) ||
- SSL_CIPHER_get_max_version(cipher) < ssl_protocol_version(ssl) ||
- !sk_SSL_CIPHER_find(SSL_get_ciphers(ssl), NULL, cipher)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CIPHER_RETURNED);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
- return ssl_hs_error;
- }
-
- if (ssl->session != NULL) {
- if (ssl->session->ssl_version != ssl->version) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_OLD_SESSION_VERSION_NOT_RETURNED);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
- return ssl_hs_error;
- }
- if (ssl->session->cipher != cipher) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_OLD_SESSION_CIPHER_NOT_RETURNED);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
- return ssl_hs_error;
- }
- if (!ssl_session_is_context_valid(hs, ssl->session.get())) {
- // This is actually a client application bug.
- OPENSSL_PUT_ERROR(SSL,
- SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
- return ssl_hs_error;
- }
- } else {
- hs->new_session->cipher = cipher;
- }
- hs->new_cipher = cipher;
-
- // Now that the cipher is known, initialize the handshake hash and hash the
- // ServerHello.
- if (!hs->transcript.InitHash(ssl_protocol_version(ssl), hs->new_cipher) ||
- !ssl_hash_message(hs, msg)) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
- return ssl_hs_error;
- }
-
- // If doing a full handshake, the server may request a client certificate
- // which requires hashing the handshake transcript. Otherwise, the handshake
- // buffer may be released.
- if (ssl->session != NULL ||
- !ssl_cipher_uses_certificate_auth(hs->new_cipher)) {
- hs->transcript.FreeBuffer();
- }
-
- // Only the NULL compression algorithm is supported.
- if (compression_method != 0) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_UNSUPPORTED_COMPRESSION_ALGORITHM);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
- return ssl_hs_error;
- }
-
- // TLS extensions
- if (!ssl_parse_serverhello_tlsext(hs, &server_hello)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_PARSE_TLSEXT);
- return ssl_hs_error;
- }
-
- // There should be nothing left over in the record.
- if (CBS_len(&server_hello) != 0) {
- // wrong packet length
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return ssl_hs_error;
- }
-
- if (ssl->session != NULL &&
- hs->extended_master_secret != ssl->session->extended_master_secret) {
- if (ssl->session->extended_master_secret) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_RESUMED_EMS_SESSION_WITHOUT_EMS_EXTENSION);
- } else {
- OPENSSL_PUT_ERROR(SSL, SSL_R_RESUMED_NON_EMS_SESSION_WITH_EMS_EXTENSION);
- }
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
- return ssl_hs_error;
- }
-
- if (ssl->s3->token_binding_negotiated &&
- (!hs->extended_master_secret || !ssl->s3->send_connection_binding)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_NEGOTIATED_TB_WITHOUT_EMS_OR_RI);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNSUPPORTED_EXTENSION);
- return ssl_hs_error;
- }
-
- ssl->method->next_message(ssl);
-
- if (ssl->session != NULL) {
- hs->state = state_read_session_ticket;
- return ssl_hs_ok;
- }
-
- hs->state = state_read_server_certificate;
- return ssl_hs_ok;
- }
-
- static enum ssl_hs_wait_t do_tls13(SSL_HANDSHAKE *hs) {
- enum ssl_hs_wait_t wait = tls13_client_handshake(hs);
- if (wait == ssl_hs_ok) {
- hs->state = state_finish_client_handshake;
- return ssl_hs_ok;
- }
-
- return wait;
- }
-
- static enum ssl_hs_wait_t do_read_server_certificate(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
-
- if (!ssl_cipher_uses_certificate_auth(hs->new_cipher)) {
- hs->state = state_read_certificate_status;
- return ssl_hs_ok;
- }
-
- SSLMessage msg;
- if (!ssl->method->get_message(ssl, &msg)) {
- return ssl_hs_read_message;
- }
-
- if (!ssl_check_message_type(ssl, msg, SSL3_MT_CERTIFICATE) ||
- !ssl_hash_message(hs, msg)) {
- return ssl_hs_error;
- }
-
- CBS body = msg.body;
- uint8_t alert = SSL_AD_DECODE_ERROR;
- if (!ssl_parse_cert_chain(&alert, &hs->new_session->certs, &hs->peer_pubkey,
- NULL, &body, ssl->ctx->pool)) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
- return ssl_hs_error;
- }
-
- if (sk_CRYPTO_BUFFER_num(hs->new_session->certs.get()) == 0 ||
- CBS_len(&body) != 0 ||
- !ssl->ctx->x509_method->session_cache_objects(hs->new_session.get())) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return ssl_hs_error;
- }
-
- if (!ssl_check_leaf_certificate(
- hs, hs->peer_pubkey.get(),
- sk_CRYPTO_BUFFER_value(hs->new_session->certs.get(), 0))) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
- return ssl_hs_error;
- }
-
- ssl->method->next_message(ssl);
-
- hs->state = state_read_certificate_status;
- return ssl_hs_ok;
- }
-
- static enum ssl_hs_wait_t do_read_certificate_status(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
-
- if (!hs->certificate_status_expected) {
- hs->state = state_verify_server_certificate;
- return ssl_hs_ok;
- }
-
- SSLMessage msg;
- if (!ssl->method->get_message(ssl, &msg)) {
- return ssl_hs_read_message;
- }
-
- if (msg.type != SSL3_MT_CERTIFICATE_STATUS) {
- // A server may send status_request in ServerHello and then change its mind
- // about sending CertificateStatus.
- hs->state = state_verify_server_certificate;
- return ssl_hs_ok;
- }
-
- if (!ssl_hash_message(hs, msg)) {
- return ssl_hs_error;
- }
-
- CBS certificate_status = msg.body, ocsp_response;
- uint8_t status_type;
- if (!CBS_get_u8(&certificate_status, &status_type) ||
- status_type != TLSEXT_STATUSTYPE_ocsp ||
- !CBS_get_u24_length_prefixed(&certificate_status, &ocsp_response) ||
- CBS_len(&ocsp_response) == 0 ||
- CBS_len(&certificate_status) != 0) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return ssl_hs_error;
- }
-
- hs->new_session->ocsp_response.reset(
- CRYPTO_BUFFER_new_from_CBS(&ocsp_response, ssl->ctx->pool));
- if (hs->new_session->ocsp_response == nullptr) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
- return ssl_hs_error;
- }
-
- ssl->method->next_message(ssl);
-
- hs->state = state_verify_server_certificate;
- return ssl_hs_ok;
- }
-
- static enum ssl_hs_wait_t do_verify_server_certificate(SSL_HANDSHAKE *hs) {
- if (!ssl_cipher_uses_certificate_auth(hs->new_cipher)) {
- hs->state = state_read_server_key_exchange;
- return ssl_hs_ok;
- }
-
- switch (ssl_verify_peer_cert(hs)) {
- case ssl_verify_ok:
- break;
- case ssl_verify_invalid:
- return ssl_hs_error;
- case ssl_verify_retry:
- hs->state = state_verify_server_certificate;
- return ssl_hs_certificate_verify;
- }
-
- hs->state = state_read_server_key_exchange;
- return ssl_hs_ok;
- }
-
- static enum ssl_hs_wait_t do_read_server_key_exchange(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
- SSLMessage msg;
- if (!ssl->method->get_message(ssl, &msg)) {
- return ssl_hs_read_message;
- }
-
- if (msg.type != SSL3_MT_SERVER_KEY_EXCHANGE) {
- // Some ciphers (pure PSK) have an optional ServerKeyExchange message.
- if (ssl_cipher_requires_server_key_exchange(hs->new_cipher)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
- return ssl_hs_error;
- }
-
- hs->state = state_read_certificate_request;
- return ssl_hs_ok;
- }
-
- if (!ssl_hash_message(hs, msg)) {
- return ssl_hs_error;
- }
-
- uint32_t alg_k = hs->new_cipher->algorithm_mkey;
- uint32_t alg_a = hs->new_cipher->algorithm_auth;
- CBS server_key_exchange = msg.body;
- if (alg_a & SSL_aPSK) {
- CBS psk_identity_hint;
-
- // Each of the PSK key exchanges begins with a psk_identity_hint.
- if (!CBS_get_u16_length_prefixed(&server_key_exchange,
- &psk_identity_hint)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return ssl_hs_error;
- }
-
- // Store the PSK identity hint for the ClientKeyExchange. Assume that the
- // maximum length of a PSK identity hint can be as long as the maximum
- // length of a PSK identity. Also do not allow NULL characters; identities
- // are saved as C strings.
- //
- // TODO(davidben): Should invalid hints be ignored? It's a hint rather than
- // a specific identity.
- if (CBS_len(&psk_identity_hint) > PSK_MAX_IDENTITY_LEN ||
- CBS_contains_zero_byte(&psk_identity_hint)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_DATA_LENGTH_TOO_LONG);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
- return ssl_hs_error;
- }
-
- // Save non-empty identity hints as a C string. Empty identity hints we
- // treat as missing. Plain PSK makes it possible to send either no hint
- // (omit ServerKeyExchange) or an empty hint, while ECDHE_PSK can only spell
- // empty hint. Having different capabilities is odd, so we interpret empty
- // and missing as identical.
- char *raw = nullptr;
- if (CBS_len(&psk_identity_hint) != 0 &&
- !CBS_strdup(&psk_identity_hint, &raw)) {
- OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
- return ssl_hs_error;
- }
- hs->peer_psk_identity_hint.reset(raw);
- }
-
- if (alg_k & SSL_kECDHE) {
- // Parse the server parameters.
- uint8_t group_type;
- uint16_t group_id;
- CBS point;
- if (!CBS_get_u8(&server_key_exchange, &group_type) ||
- group_type != NAMED_CURVE_TYPE ||
- !CBS_get_u16(&server_key_exchange, &group_id) ||
- !CBS_get_u8_length_prefixed(&server_key_exchange, &point)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return ssl_hs_error;
- }
- hs->new_session->group_id = group_id;
-
- // Ensure the group is consistent with preferences.
- if (!tls1_check_group_id(hs, group_id)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CURVE);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
- return ssl_hs_error;
- }
-
- // Initialize ECDH and save the peer public key for later.
- hs->key_share = SSLKeyShare::Create(group_id);
- if (!hs->key_share ||
- !hs->peer_key.CopyFrom(point)) {
- return ssl_hs_error;
- }
- } else if (!(alg_k & SSL_kPSK)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
- return ssl_hs_error;
- }
-
- // At this point, |server_key_exchange| contains the signature, if any, while
- // |msg.body| contains the entire message. From that, derive a CBS containing
- // just the parameter.
- CBS parameter;
- CBS_init(¶meter, CBS_data(&msg.body),
- CBS_len(&msg.body) - CBS_len(&server_key_exchange));
-
- // ServerKeyExchange should be signed by the server's public key.
- if (ssl_cipher_uses_certificate_auth(hs->new_cipher)) {
- uint16_t signature_algorithm = 0;
- if (ssl_protocol_version(ssl) >= TLS1_2_VERSION) {
- if (!CBS_get_u16(&server_key_exchange, &signature_algorithm)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return ssl_hs_error;
- }
- uint8_t alert = SSL_AD_DECODE_ERROR;
- if (!tls12_check_peer_sigalg(ssl, &alert, signature_algorithm)) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
- return ssl_hs_error;
- }
- hs->new_session->peer_signature_algorithm = signature_algorithm;
- } else if (!tls1_get_legacy_signature_algorithm(&signature_algorithm,
- hs->peer_pubkey.get())) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_PEER_ERROR_UNSUPPORTED_CERTIFICATE_TYPE);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNSUPPORTED_CERTIFICATE);
- return ssl_hs_error;
- }
-
- // The last field in |server_key_exchange| is the signature.
- CBS signature;
- if (!CBS_get_u16_length_prefixed(&server_key_exchange, &signature) ||
- CBS_len(&server_key_exchange) != 0) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return ssl_hs_error;
- }
-
- ScopedCBB transcript;
- Array<uint8_t> transcript_data;
- if (!CBB_init(transcript.get(),
- 2 * SSL3_RANDOM_SIZE + CBS_len(¶meter)) ||
- !CBB_add_bytes(transcript.get(), ssl->s3->client_random,
- SSL3_RANDOM_SIZE) ||
- !CBB_add_bytes(transcript.get(), ssl->s3->server_random,
- SSL3_RANDOM_SIZE) ||
- !CBB_add_bytes(transcript.get(), CBS_data(¶meter),
- CBS_len(¶meter)) ||
- !CBBFinishArray(transcript.get(), &transcript_data)) {
- OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
- return ssl_hs_error;
- }
-
- bool sig_ok = ssl_public_key_verify(ssl, signature, signature_algorithm,
- hs->peer_pubkey.get(), transcript_data);
- #if defined(BORINGSSL_UNSAFE_FUZZER_MODE)
- sig_ok = true;
- ERR_clear_error();
- #endif
- if (!sig_ok) {
- // bad signature
- OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_SIGNATURE);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECRYPT_ERROR);
- return ssl_hs_error;
- }
- } else {
- // PSK ciphers are the only supported certificate-less ciphers.
- assert(alg_a == SSL_aPSK);
-
- if (CBS_len(&server_key_exchange) > 0) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_EXTRA_DATA_IN_MESSAGE);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return ssl_hs_error;
- }
- }
-
- ssl->method->next_message(ssl);
- hs->state = state_read_certificate_request;
- return ssl_hs_ok;
- }
-
- static enum ssl_hs_wait_t do_read_certificate_request(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
-
- if (!ssl_cipher_uses_certificate_auth(hs->new_cipher)) {
- hs->state = state_read_server_hello_done;
- return ssl_hs_ok;
- }
-
- SSLMessage msg;
- if (!ssl->method->get_message(ssl, &msg)) {
- return ssl_hs_read_message;
- }
-
- if (msg.type == SSL3_MT_SERVER_HELLO_DONE) {
- // If we get here we don't need the handshake buffer as we won't be doing
- // client auth.
- hs->transcript.FreeBuffer();
- hs->state = state_read_server_hello_done;
- return ssl_hs_ok;
- }
-
- if (!ssl_check_message_type(ssl, msg, SSL3_MT_CERTIFICATE_REQUEST) ||
- !ssl_hash_message(hs, msg)) {
- return ssl_hs_error;
- }
-
- // Get the certificate types.
- CBS body = msg.body, certificate_types;
- if (!CBS_get_u8_length_prefixed(&body, &certificate_types)) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- return ssl_hs_error;
- }
-
- if (!hs->certificate_types.CopyFrom(certificate_types)) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
- return ssl_hs_error;
- }
-
- if (ssl_protocol_version(ssl) >= TLS1_2_VERSION) {
- CBS supported_signature_algorithms;
- if (!CBS_get_u16_length_prefixed(&body, &supported_signature_algorithms) ||
- !tls1_parse_peer_sigalgs(hs, &supported_signature_algorithms)) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- return ssl_hs_error;
- }
- }
-
- uint8_t alert = SSL_AD_DECODE_ERROR;
- UniquePtr<STACK_OF(CRYPTO_BUFFER)> ca_names =
- ssl_parse_client_CA_list(ssl, &alert, &body);
- if (!ca_names) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
- return ssl_hs_error;
- }
-
- if (CBS_len(&body) != 0) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- return ssl_hs_error;
- }
-
- hs->cert_request = true;
- hs->ca_names = std::move(ca_names);
- ssl->ctx->x509_method->hs_flush_cached_ca_names(hs);
-
- ssl->method->next_message(ssl);
- hs->state = state_read_server_hello_done;
- return ssl_hs_ok;
- }
-
- static enum ssl_hs_wait_t do_read_server_hello_done(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
- SSLMessage msg;
- if (!ssl->method->get_message(ssl, &msg)) {
- return ssl_hs_read_message;
- }
-
- if (!ssl_check_message_type(ssl, msg, SSL3_MT_SERVER_HELLO_DONE) ||
- !ssl_hash_message(hs, msg)) {
- return ssl_hs_error;
- }
-
- // ServerHelloDone is empty.
- if (CBS_len(&msg.body) != 0) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- return ssl_hs_error;
- }
-
- ssl->method->next_message(ssl);
- hs->state = state_send_client_certificate;
- return ssl_hs_ok;
- }
-
- static enum ssl_hs_wait_t do_send_client_certificate(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
-
- // The peer didn't request a certificate.
- if (!hs->cert_request) {
- hs->state = state_send_client_key_exchange;
- return ssl_hs_ok;
- }
-
- // Call cert_cb to update the certificate.
- if (hs->config->cert->cert_cb != NULL) {
- int rv = hs->config->cert->cert_cb(ssl, hs->config->cert->cert_cb_arg);
- if (rv == 0) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
- OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_CB_ERROR);
- return ssl_hs_error;
- }
- if (rv < 0) {
- hs->state = state_send_client_certificate;
- return ssl_hs_x509_lookup;
- }
- }
-
- if (!ssl_has_certificate(hs->config)) {
- // Without a client certificate, the handshake buffer may be released.
- hs->transcript.FreeBuffer();
- }
-
- if (!ssl_on_certificate_selected(hs) ||
- !ssl_output_cert_chain(hs)) {
- return ssl_hs_error;
- }
-
-
- hs->state = state_send_client_key_exchange;
- return ssl_hs_ok;
- }
-
- static_assert(sizeof(size_t) >= sizeof(unsigned),
- "size_t is smaller than unsigned");
-
- static enum ssl_hs_wait_t do_send_client_key_exchange(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
- ScopedCBB cbb;
- CBB body;
- if (!ssl->method->init_message(ssl, cbb.get(), &body,
- SSL3_MT_CLIENT_KEY_EXCHANGE)) {
- return ssl_hs_error;
- }
-
- Array<uint8_t> pms;
- uint32_t alg_k = hs->new_cipher->algorithm_mkey;
- uint32_t alg_a = hs->new_cipher->algorithm_auth;
-
- // If using a PSK key exchange, prepare the pre-shared key.
- unsigned psk_len = 0;
- uint8_t psk[PSK_MAX_PSK_LEN];
- if (alg_a & SSL_aPSK) {
- if (hs->config->psk_client_callback == NULL) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_PSK_NO_CLIENT_CB);
- return ssl_hs_error;
- }
-
- char identity[PSK_MAX_IDENTITY_LEN + 1];
- OPENSSL_memset(identity, 0, sizeof(identity));
- psk_len = hs->config->psk_client_callback(
- ssl, hs->peer_psk_identity_hint.get(), identity, sizeof(identity), psk,
- sizeof(psk));
- if (psk_len == 0) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_PSK_IDENTITY_NOT_FOUND);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
- return ssl_hs_error;
- }
- assert(psk_len <= PSK_MAX_PSK_LEN);
-
- hs->new_session->psk_identity.reset(BUF_strdup(identity));
- if (hs->new_session->psk_identity == nullptr) {
- OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
- return ssl_hs_error;
- }
-
- // Write out psk_identity.
- CBB child;
- if (!CBB_add_u16_length_prefixed(&body, &child) ||
- !CBB_add_bytes(&child, (const uint8_t *)identity,
- OPENSSL_strnlen(identity, sizeof(identity))) ||
- !CBB_flush(&body)) {
- return ssl_hs_error;
- }
- }
-
- // Depending on the key exchange method, compute |pms|.
- if (alg_k & SSL_kRSA) {
- if (!pms.Init(SSL_MAX_MASTER_KEY_LENGTH)) {
- return ssl_hs_error;
- }
-
- RSA *rsa = EVP_PKEY_get0_RSA(hs->peer_pubkey.get());
- if (rsa == NULL) {
- OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
- return ssl_hs_error;
- }
-
- pms[0] = hs->client_version >> 8;
- pms[1] = hs->client_version & 0xff;
- if (!RAND_bytes(&pms[2], SSL_MAX_MASTER_KEY_LENGTH - 2)) {
- return ssl_hs_error;
- }
-
- CBB enc_pms;
- uint8_t *ptr;
- size_t enc_pms_len;
- if (!CBB_add_u16_length_prefixed(&body, &enc_pms) ||
- !CBB_reserve(&enc_pms, &ptr, RSA_size(rsa)) ||
- !RSA_encrypt(rsa, &enc_pms_len, ptr, RSA_size(rsa), pms.data(),
- pms.size(), RSA_PKCS1_PADDING) ||
- !CBB_did_write(&enc_pms, enc_pms_len) ||
- !CBB_flush(&body)) {
- return ssl_hs_error;
- }
- } else if (alg_k & SSL_kECDHE) {
- // Generate a keypair and serialize the public half.
- CBB child;
- if (!CBB_add_u8_length_prefixed(&body, &child)) {
- return ssl_hs_error;
- }
-
- // Compute the premaster.
- uint8_t alert = SSL_AD_DECODE_ERROR;
- if (!hs->key_share->Accept(&child, &pms, &alert, hs->peer_key)) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
- return ssl_hs_error;
- }
- if (!CBB_flush(&body)) {
- return ssl_hs_error;
- }
-
- // The key exchange state may now be discarded.
- hs->key_share.reset();
- hs->peer_key.Reset();
- } else if (alg_k & SSL_kPSK) {
- // For plain PSK, other_secret is a block of 0s with the same length as
- // the pre-shared key.
- if (!pms.Init(psk_len)) {
- return ssl_hs_error;
- }
- OPENSSL_memset(pms.data(), 0, pms.size());
- } else {
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
- OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
- return ssl_hs_error;
- }
-
- // For a PSK cipher suite, other_secret is combined with the pre-shared
- // key.
- if (alg_a & SSL_aPSK) {
- ScopedCBB pms_cbb;
- CBB child;
- if (!CBB_init(pms_cbb.get(), 2 + psk_len + 2 + pms.size()) ||
- !CBB_add_u16_length_prefixed(pms_cbb.get(), &child) ||
- !CBB_add_bytes(&child, pms.data(), pms.size()) ||
- !CBB_add_u16_length_prefixed(pms_cbb.get(), &child) ||
- !CBB_add_bytes(&child, psk, psk_len) ||
- !CBBFinishArray(pms_cbb.get(), &pms)) {
- OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
- return ssl_hs_error;
- }
- }
-
- // The message must be added to the finished hash before calculating the
- // master secret.
- if (!ssl_add_message_cbb(ssl, cbb.get())) {
- return ssl_hs_error;
- }
-
- hs->new_session->master_key_length =
- tls1_generate_master_secret(hs, hs->new_session->master_key, pms);
- if (hs->new_session->master_key_length == 0) {
- return ssl_hs_error;
- }
- hs->new_session->extended_master_secret = hs->extended_master_secret;
-
- hs->state = state_send_client_certificate_verify;
- return ssl_hs_ok;
- }
-
- static enum ssl_hs_wait_t do_send_client_certificate_verify(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
-
- if (!hs->cert_request || !ssl_has_certificate(hs->config)) {
- hs->state = state_send_client_finished;
- return ssl_hs_ok;
- }
-
- assert(ssl_has_private_key(hs->config));
- ScopedCBB cbb;
- CBB body, child;
- if (!ssl->method->init_message(ssl, cbb.get(), &body,
- SSL3_MT_CERTIFICATE_VERIFY)) {
- return ssl_hs_error;
- }
-
- uint16_t signature_algorithm;
- if (!tls1_choose_signature_algorithm(hs, &signature_algorithm)) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
- return ssl_hs_error;
- }
- if (ssl_protocol_version(ssl) >= TLS1_2_VERSION) {
- // Write out the digest type in TLS 1.2.
- if (!CBB_add_u16(&body, signature_algorithm)) {
- OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
- return ssl_hs_error;
- }
- }
-
- // Set aside space for the signature.
- const size_t max_sig_len = EVP_PKEY_size(hs->local_pubkey.get());
- uint8_t *ptr;
- if (!CBB_add_u16_length_prefixed(&body, &child) ||
- !CBB_reserve(&child, &ptr, max_sig_len)) {
- return ssl_hs_error;
- }
-
- size_t sig_len = max_sig_len;
- switch (ssl_private_key_sign(hs, ptr, &sig_len, max_sig_len,
- signature_algorithm,
- hs->transcript.buffer())) {
- case ssl_private_key_success:
- break;
- case ssl_private_key_failure:
- return ssl_hs_error;
- case ssl_private_key_retry:
- hs->state = state_send_client_certificate_verify;
- return ssl_hs_private_key_operation;
- }
-
- if (!CBB_did_write(&child, sig_len) ||
- !ssl_add_message_cbb(ssl, cbb.get())) {
- return ssl_hs_error;
- }
-
- // The handshake buffer is no longer necessary.
- hs->transcript.FreeBuffer();
-
- hs->state = state_send_client_finished;
- return ssl_hs_ok;
- }
-
- static enum ssl_hs_wait_t do_send_client_finished(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
- // Resolve Channel ID first, before any non-idempotent operations.
- if (ssl->s3->channel_id_valid) {
- if (!ssl_do_channel_id_callback(hs)) {
- return ssl_hs_error;
- }
-
- if (hs->config->channel_id_private == NULL) {
- hs->state = state_send_client_finished;
- return ssl_hs_channel_id_lookup;
- }
- }
-
- if (!ssl->method->add_change_cipher_spec(ssl) ||
- !tls1_change_cipher_state(hs, evp_aead_seal)) {
- return ssl_hs_error;
- }
-
- if (hs->next_proto_neg_seen) {
- static const uint8_t kZero[32] = {0};
- size_t padding_len =
- 32 - ((ssl->s3->next_proto_negotiated.size() + 2) % 32);
-
- ScopedCBB cbb;
- CBB body, child;
- if (!ssl->method->init_message(ssl, cbb.get(), &body, SSL3_MT_NEXT_PROTO) ||
- !CBB_add_u8_length_prefixed(&body, &child) ||
- !CBB_add_bytes(&child, ssl->s3->next_proto_negotiated.data(),
- ssl->s3->next_proto_negotiated.size()) ||
- !CBB_add_u8_length_prefixed(&body, &child) ||
- !CBB_add_bytes(&child, kZero, padding_len) ||
- !ssl_add_message_cbb(ssl, cbb.get())) {
- OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
- return ssl_hs_error;
- }
- }
-
- if (ssl->s3->channel_id_valid) {
- ScopedCBB cbb;
- CBB body;
- if (!ssl->method->init_message(ssl, cbb.get(), &body, SSL3_MT_CHANNEL_ID) ||
- !tls1_write_channel_id(hs, &body) ||
- !ssl_add_message_cbb(ssl, cbb.get())) {
- OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
- return ssl_hs_error;
- }
- }
-
- if (!ssl_send_finished(hs)) {
- return ssl_hs_error;
- }
-
- hs->state = state_finish_flight;
- return ssl_hs_flush;
- }
-
- static bool can_false_start(const SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
-
- // False Start only for TLS 1.2 with an ECDHE+AEAD cipher.
- if (SSL_is_dtls(ssl) ||
- SSL_version(ssl) != TLS1_2_VERSION ||
- hs->new_cipher->algorithm_mkey != SSL_kECDHE ||
- hs->new_cipher->algorithm_mac != SSL_AEAD) {
- return false;
- }
-
- // Additionally require ALPN or NPN by default.
- //
- // TODO(davidben): Can this constraint be relaxed globally now that cipher
- // suite requirements have been relaxed?
- if (!ssl->ctx->false_start_allowed_without_alpn &&
- ssl->s3->alpn_selected.empty() &&
- ssl->s3->next_proto_negotiated.empty()) {
- return false;
- }
-
- return true;
- }
-
- static enum ssl_hs_wait_t do_finish_flight(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
- if (ssl->session != NULL) {
- hs->state = state_finish_client_handshake;
- return ssl_hs_ok;
- }
-
- // This is a full handshake. If it involves ChannelID, then record the
- // handshake hashes at this point in the session so that any resumption of
- // this session with ChannelID can sign those hashes.
- if (!tls1_record_handshake_hashes_for_channel_id(hs)) {
- return ssl_hs_error;
- }
-
- hs->state = state_read_session_ticket;
-
- if ((SSL_get_mode(ssl) & SSL_MODE_ENABLE_FALSE_START) &&
- can_false_start(hs) &&
- // No False Start on renegotiation (would complicate the state machine).
- !ssl->s3->initial_handshake_complete) {
- hs->in_false_start = true;
- hs->can_early_write = true;
- return ssl_hs_early_return;
- }
-
- return ssl_hs_ok;
- }
-
- static enum ssl_hs_wait_t do_read_session_ticket(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
-
- if (!hs->ticket_expected) {
- hs->state = state_process_change_cipher_spec;
- return ssl_hs_read_change_cipher_spec;
- }
-
- SSLMessage msg;
- if (!ssl->method->get_message(ssl, &msg)) {
- return ssl_hs_read_message;
- }
-
- if (!ssl_check_message_type(ssl, msg, SSL3_MT_NEW_SESSION_TICKET) ||
- !ssl_hash_message(hs, msg)) {
- return ssl_hs_error;
- }
-
- CBS new_session_ticket = msg.body, ticket;
- uint32_t ticket_lifetime_hint;
- if (!CBS_get_u32(&new_session_ticket, &ticket_lifetime_hint) ||
- !CBS_get_u16_length_prefixed(&new_session_ticket, &ticket) ||
- CBS_len(&new_session_ticket) != 0) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- return ssl_hs_error;
- }
-
- if (CBS_len(&ticket) == 0) {
- // RFC 5077 allows a server to change its mind and send no ticket after
- // negotiating the extension. The value of |ticket_expected| is checked in
- // |ssl_update_cache| so is cleared here to avoid an unnecessary update.
- hs->ticket_expected = false;
- ssl->method->next_message(ssl);
- hs->state = state_process_change_cipher_spec;
- return ssl_hs_read_change_cipher_spec;
- }
-
- SSL_SESSION *session = hs->new_session.get();
- UniquePtr<SSL_SESSION> renewed_session;
- if (ssl->session != NULL) {
- // The server is sending a new ticket for an existing session. Sessions are
- // immutable once established, so duplicate all but the ticket of the
- // existing session.
- renewed_session =
- SSL_SESSION_dup(ssl->session.get(), SSL_SESSION_INCLUDE_NONAUTH);
- if (!renewed_session) {
- // This should never happen.
- OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
- return ssl_hs_error;
- }
- session = renewed_session.get();
- }
-
- // |ticket_lifetime_hint| is measured from when the ticket was issued.
- ssl_session_rebase_time(ssl, session);
-
- if (!session->ticket.CopyFrom(ticket)) {
- return ssl_hs_error;
- }
- session->ticket_lifetime_hint = ticket_lifetime_hint;
-
- // Generate a session ID for this session based on the session ticket. We use
- // the session ID mechanism for detecting ticket resumption. This also fits in
- // with assumptions elsewhere in OpenSSL.
- if (!EVP_Digest(CBS_data(&ticket), CBS_len(&ticket),
- session->session_id, &session->session_id_length,
- EVP_sha256(), NULL)) {
- return ssl_hs_error;
- }
-
- if (renewed_session) {
- session->not_resumable = false;
- ssl->session = std::move(renewed_session);
- }
-
- ssl->method->next_message(ssl);
- hs->state = state_process_change_cipher_spec;
- return ssl_hs_read_change_cipher_spec;
- }
-
- static enum ssl_hs_wait_t do_process_change_cipher_spec(SSL_HANDSHAKE *hs) {
- if (!tls1_change_cipher_state(hs, evp_aead_open)) {
- return ssl_hs_error;
- }
-
- hs->state = state_read_server_finished;
- return ssl_hs_ok;
- }
-
- static enum ssl_hs_wait_t do_read_server_finished(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
- enum ssl_hs_wait_t wait = ssl_get_finished(hs);
- if (wait != ssl_hs_ok) {
- return wait;
- }
-
- if (ssl->session != NULL) {
- hs->state = state_send_client_finished;
- return ssl_hs_ok;
- }
-
- hs->state = state_finish_client_handshake;
- return ssl_hs_ok;
- }
-
- static enum ssl_hs_wait_t do_finish_client_handshake(SSL_HANDSHAKE *hs) {
- SSL *const ssl = hs->ssl;
-
- ssl->method->on_handshake_complete(ssl);
-
- if (ssl->session != NULL) {
- ssl->s3->established_session = UpRef(ssl->session);
- } else {
- // We make a copy of the session in order to maintain the immutability
- // of the new established_session due to False Start. The caller may
- // have taken a reference to the temporary session.
- ssl->s3->established_session =
- SSL_SESSION_dup(hs->new_session.get(), SSL_SESSION_DUP_ALL);
- if (!ssl->s3->established_session) {
- return ssl_hs_error;
- }
- // Renegotiations do not participate in session resumption.
- if (!ssl->s3->initial_handshake_complete) {
- ssl->s3->established_session->not_resumable = false;
- }
-
- hs->new_session.reset();
- }
-
- hs->handshake_finalized = true;
- ssl->s3->initial_handshake_complete = true;
- ssl_update_cache(hs, SSL_SESS_CACHE_CLIENT);
-
- hs->state = state_done;
- return ssl_hs_ok;
- }
-
- enum ssl_hs_wait_t ssl_client_handshake(SSL_HANDSHAKE *hs) {
- while (hs->state != state_done) {
- enum ssl_hs_wait_t ret = ssl_hs_error;
- enum ssl_client_hs_state_t state =
- static_cast<enum ssl_client_hs_state_t>(hs->state);
- switch (state) {
- case state_start_connect:
- ret = do_start_connect(hs);
- break;
- case state_enter_early_data:
- ret = do_enter_early_data(hs);
- break;
- case state_read_hello_verify_request:
- ret = do_read_hello_verify_request(hs);
- break;
- case state_read_server_hello:
- ret = do_read_server_hello(hs);
- break;
- case state_tls13:
- ret = do_tls13(hs);
- break;
- case state_read_server_certificate:
- ret = do_read_server_certificate(hs);
- break;
- case state_read_certificate_status:
- ret = do_read_certificate_status(hs);
- break;
- case state_verify_server_certificate:
- ret = do_verify_server_certificate(hs);
- break;
- case state_read_server_key_exchange:
- ret = do_read_server_key_exchange(hs);
- break;
- case state_read_certificate_request:
- ret = do_read_certificate_request(hs);
- break;
- case state_read_server_hello_done:
- ret = do_read_server_hello_done(hs);
- break;
- case state_send_client_certificate:
- ret = do_send_client_certificate(hs);
- break;
- case state_send_client_key_exchange:
- ret = do_send_client_key_exchange(hs);
- break;
- case state_send_client_certificate_verify:
- ret = do_send_client_certificate_verify(hs);
- break;
- case state_send_client_finished:
- ret = do_send_client_finished(hs);
- break;
- case state_finish_flight:
- ret = do_finish_flight(hs);
- break;
- case state_read_session_ticket:
- ret = do_read_session_ticket(hs);
- break;
- case state_process_change_cipher_spec:
- ret = do_process_change_cipher_spec(hs);
- break;
- case state_read_server_finished:
- ret = do_read_server_finished(hs);
- break;
- case state_finish_client_handshake:
- ret = do_finish_client_handshake(hs);
- break;
- case state_done:
- ret = ssl_hs_ok;
- break;
- }
-
- if (hs->state != state) {
- ssl_do_info_callback(hs->ssl, SSL_CB_CONNECT_LOOP, 1);
- }
-
- if (ret != ssl_hs_ok) {
- return ret;
- }
- }
-
- ssl_do_info_callback(hs->ssl, SSL_CB_HANDSHAKE_DONE, 1);
- return ssl_hs_ok;
- }
-
- const char *ssl_client_handshake_state(SSL_HANDSHAKE *hs) {
- enum ssl_client_hs_state_t state =
- static_cast<enum ssl_client_hs_state_t>(hs->state);
- switch (state) {
- case state_start_connect:
- return "TLS client start_connect";
- case state_enter_early_data:
- return "TLS client enter_early_data";
- case state_read_hello_verify_request:
- return "TLS client read_hello_verify_request";
- case state_read_server_hello:
- return "TLS client read_server_hello";
- case state_tls13:
- return tls13_client_handshake_state(hs);
- case state_read_server_certificate:
- return "TLS client read_server_certificate";
- case state_read_certificate_status:
- return "TLS client read_certificate_status";
- case state_verify_server_certificate:
- return "TLS client verify_server_certificate";
- case state_read_server_key_exchange:
- return "TLS client read_server_key_exchange";
- case state_read_certificate_request:
- return "TLS client read_certificate_request";
- case state_read_server_hello_done:
- return "TLS client read_server_hello_done";
- case state_send_client_certificate:
- return "TLS client send_client_certificate";
- case state_send_client_key_exchange:
- return "TLS client send_client_key_exchange";
- case state_send_client_certificate_verify:
- return "TLS client send_client_certificate_verify";
- case state_send_client_finished:
- return "TLS client send_client_finished";
- case state_finish_flight:
- return "TLS client finish_flight";
- case state_read_session_ticket:
- return "TLS client read_session_ticket";
- case state_process_change_cipher_spec:
- return "TLS client process_change_cipher_spec";
- case state_read_server_finished:
- return "TLS client read_server_finished";
- case state_finish_client_handshake:
- return "TLS client finish_client_handshake";
- case state_done:
- return "TLS client done";
- }
-
- return "TLS client unknown";
- }
-
- }
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