/* 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include "../crypto/internal.h" #include "internal.h" static int ssl3_send_client_hello(SSL_HANDSHAKE *hs); static int dtls1_get_hello_verify_request(SSL_HANDSHAKE *hs); static int ssl3_get_server_hello(SSL_HANDSHAKE *hs); static int ssl3_get_server_certificate(SSL_HANDSHAKE *hs); static int ssl3_get_cert_status(SSL_HANDSHAKE *hs); static int ssl3_verify_server_cert(SSL_HANDSHAKE *hs); static int ssl3_get_server_key_exchange(SSL_HANDSHAKE *hs); static int ssl3_get_certificate_request(SSL_HANDSHAKE *hs); static int ssl3_get_server_hello_done(SSL_HANDSHAKE *hs); static int ssl3_send_client_certificate(SSL_HANDSHAKE *hs); static int ssl3_send_client_key_exchange(SSL_HANDSHAKE *hs); static int ssl3_send_cert_verify(SSL_HANDSHAKE *hs); static int ssl3_send_next_proto(SSL_HANDSHAKE *hs); static int ssl3_send_channel_id(SSL_HANDSHAKE *hs); static int ssl3_get_new_session_ticket(SSL_HANDSHAKE *hs); int ssl3_connect(SSL_HANDSHAKE *hs) { SSL *const ssl = hs->ssl; int ret = -1; assert(ssl->handshake_func == ssl3_connect); assert(!ssl->server); for (;;) { int state = hs->state; switch (hs->state) { case SSL_ST_INIT: ssl_do_info_callback(ssl, SSL_CB_HANDSHAKE_START, 1); hs->state = SSL3_ST_CW_CLNT_HELLO_A; break; case SSL3_ST_CW_CLNT_HELLO_A: ret = ssl3_send_client_hello(hs); if (ret <= 0) { goto end; } if (!SSL_is_dtls(ssl) || ssl->d1->send_cookie) { if (hs->early_data_offered) { if (!tls13_init_early_key_schedule(hs) || !tls13_advance_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)) { ret = -1; goto end; } hs->next_state = SSL3_ST_WRITE_EARLY_DATA; } else { hs->next_state = SSL3_ST_CR_SRVR_HELLO_A; } } else { hs->next_state = DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A; } hs->state = SSL3_ST_CW_FLUSH; break; case DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A: assert(SSL_is_dtls(ssl)); ret = dtls1_get_hello_verify_request(hs); if (ret <= 0) { goto end; } if (ssl->d1->send_cookie) { ssl->method->received_flight(ssl); hs->state = SSL3_ST_CW_CLNT_HELLO_A; } else { hs->state = SSL3_ST_CR_SRVR_HELLO_A; } break; case SSL3_ST_WRITE_EARLY_DATA: /* Stash the early data session, so connection properties may be queried * out of it. */ hs->in_early_data = 1; hs->early_session = ssl->session; SSL_SESSION_up_ref(ssl->session); hs->state = SSL3_ST_CR_SRVR_HELLO_A; hs->can_early_write = 1; ret = 1; goto end; case SSL3_ST_CR_SRVR_HELLO_A: ret = ssl3_get_server_hello(hs); if (hs->state == SSL_ST_TLS13) { break; } if (ret <= 0) { goto end; } if (ssl->session != NULL) { hs->state = SSL3_ST_CR_SESSION_TICKET_A; } else { hs->state = SSL3_ST_CR_CERT_A; } break; case SSL3_ST_CR_CERT_A: if (ssl_cipher_uses_certificate_auth(hs->new_cipher)) { ret = ssl3_get_server_certificate(hs); if (ret <= 0) { goto end; } } hs->state = SSL3_ST_CR_CERT_STATUS_A; break; case SSL3_ST_CR_CERT_STATUS_A: if (hs->certificate_status_expected) { ret = ssl3_get_cert_status(hs); if (ret <= 0) { goto end; } } hs->state = SSL3_ST_VERIFY_SERVER_CERT; break; case SSL3_ST_VERIFY_SERVER_CERT: if (ssl_cipher_uses_certificate_auth(hs->new_cipher)) { ret = ssl3_verify_server_cert(hs); if (ret <= 0) { goto end; } } hs->state = SSL3_ST_CR_KEY_EXCH_A; break; case SSL3_ST_CR_KEY_EXCH_A: ret = ssl3_get_server_key_exchange(hs); if (ret <= 0) { goto end; } hs->state = SSL3_ST_CR_CERT_REQ_A; break; case SSL3_ST_CR_CERT_REQ_A: if (ssl_cipher_uses_certificate_auth(hs->new_cipher)) { ret = ssl3_get_certificate_request(hs); if (ret <= 0) { goto end; } } hs->state = SSL3_ST_CR_SRVR_DONE_A; break; case SSL3_ST_CR_SRVR_DONE_A: ret = ssl3_get_server_hello_done(hs); if (ret <= 0) { goto end; } ssl->method->received_flight(ssl); hs->state = SSL3_ST_CW_CERT_A; break; case SSL3_ST_CW_CERT_A: if (hs->cert_request) { ret = ssl3_send_client_certificate(hs); if (ret <= 0) { goto end; } } hs->state = SSL3_ST_CW_KEY_EXCH_A; break; case SSL3_ST_CW_KEY_EXCH_A: ret = ssl3_send_client_key_exchange(hs); if (ret <= 0) { goto end; } hs->state = SSL3_ST_CW_CERT_VRFY_A; break; case SSL3_ST_CW_CERT_VRFY_A: if (hs->cert_request && ssl_has_certificate(ssl)) { ret = ssl3_send_cert_verify(hs); if (ret <= 0) { goto end; } } hs->state = SSL3_ST_CW_CHANGE; break; case SSL3_ST_CW_CHANGE: if (!ssl->method->add_change_cipher_spec(ssl) || !tls1_change_cipher_state(hs, SSL3_CHANGE_CIPHER_CLIENT_WRITE)) { ret = -1; goto end; } hs->state = SSL3_ST_CW_NEXT_PROTO_A; break; case SSL3_ST_CW_NEXT_PROTO_A: if (hs->next_proto_neg_seen) { ret = ssl3_send_next_proto(hs); if (ret <= 0) { goto end; } } hs->state = SSL3_ST_CW_CHANNEL_ID_A; break; case SSL3_ST_CW_CHANNEL_ID_A: if (ssl->s3->tlsext_channel_id_valid) { ret = ssl3_send_channel_id(hs); if (ret <= 0) { goto end; } } hs->state = SSL3_ST_CW_FINISHED_A; break; case SSL3_ST_CW_FINISHED_A: ret = ssl3_send_finished(hs); if (ret <= 0) { goto end; } hs->state = SSL3_ST_CW_FLUSH; if (ssl->session != NULL) { hs->next_state = SSL3_ST_FINISH_CLIENT_HANDSHAKE; } else { /* This is a non-resumption 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. */ ret = tls1_record_handshake_hashes_for_channel_id(hs); if (ret <= 0) { goto end; } if ((SSL_get_mode(ssl) & SSL_MODE_ENABLE_FALSE_START) && ssl3_can_false_start(ssl) && /* No False Start on renegotiation (would complicate the state * machine). */ !ssl->s3->initial_handshake_complete) { hs->next_state = SSL3_ST_FALSE_START; } else { hs->next_state = SSL3_ST_CR_SESSION_TICKET_A; } } break; case SSL3_ST_FALSE_START: hs->state = SSL3_ST_CR_SESSION_TICKET_A; hs->in_false_start = 1; hs->can_early_write = 1; ret = 1; goto end; case SSL3_ST_CR_SESSION_TICKET_A: if (hs->ticket_expected) { ret = ssl3_get_new_session_ticket(hs); if (ret <= 0) { goto end; } } hs->state = SSL3_ST_CR_CHANGE; break; case SSL3_ST_CR_CHANGE: ret = ssl->method->read_change_cipher_spec(ssl); if (ret <= 0) { goto end; } if (!tls1_change_cipher_state(hs, SSL3_CHANGE_CIPHER_CLIENT_READ)) { ret = -1; goto end; } hs->state = SSL3_ST_CR_FINISHED_A; break; case SSL3_ST_CR_FINISHED_A: ret = ssl3_get_finished(hs); if (ret <= 0) { goto end; } ssl->method->received_flight(ssl); if (ssl->session != NULL) { hs->state = SSL3_ST_CW_CHANGE; } else { hs->state = SSL3_ST_FINISH_CLIENT_HANDSHAKE; } break; case SSL3_ST_CW_FLUSH: ret = ssl->method->flush_flight(ssl); if (ret <= 0) { goto end; } hs->state = hs->next_state; if (hs->state != SSL3_ST_FINISH_CLIENT_HANDSHAKE) { ssl->method->expect_flight(ssl); } break; case SSL_ST_TLS13: { int early_return = 0; ret = tls13_handshake(hs, &early_return); if (ret <= 0) { goto end; } if (early_return) { ret = 1; goto end; } hs->state = SSL3_ST_FINISH_CLIENT_HANDSHAKE; break; } case SSL3_ST_FINISH_CLIENT_HANDSHAKE: ssl->method->release_current_message(ssl, 1 /* free_buffer */); SSL_SESSION_free(ssl->s3->established_session); if (ssl->session != NULL) { SSL_SESSION_up_ref(ssl->session); ssl->s3->established_session = 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, SSL_SESSION_DUP_ALL); if (ssl->s3->established_session == NULL) { ret = -1; goto end; } ssl->s3->established_session->not_resumable = 0; SSL_SESSION_free(hs->new_session); hs->new_session = NULL; } hs->state = SSL_ST_OK; break; case SSL_ST_OK: { const int is_initial_handshake = !ssl->s3->initial_handshake_complete; ssl->s3->initial_handshake_complete = 1; if (is_initial_handshake) { /* Renegotiations do not participate in session resumption. */ ssl_update_cache(hs, SSL_SESS_CACHE_CLIENT); } ret = 1; ssl_do_info_callback(ssl, SSL_CB_HANDSHAKE_DONE, 1); goto end; } default: OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_STATE); ret = -1; goto end; } if (hs->state != state) { ssl_do_info_callback(ssl, SSL_CB_CONNECT_LOOP, 1); } } end: ssl_do_info_callback(ssl, SSL_CB_CONNECT_EXIT, ret); return ret; } uint16_t ssl_get_grease_value(const SSL *ssl, enum ssl_grease_index_t index) { /* Use the client_random for entropy. This both avoids calling |RAND_bytes| on * a single byte repeatedly and ensures the values are 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 ret = ssl->s3->client_random[index]; /* This generates a random value of the form 0xωaωa, for all 0 ≤ ω < 16. */ ret = (ret & 0xf0) | 0x0a; ret |= ret << 8; return ret; } /* ssl_get_client_disabled sets |*out_mask_a| and |*out_mask_k| to masks of * disabled algorithms. */ static void ssl_get_client_disabled(SSL *ssl, uint32_t *out_mask_a, uint32_t *out_mask_k) { *out_mask_a = 0; *out_mask_k = 0; /* PSK requires a client callback. */ if (ssl->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(ssl, &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(ssl, 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) { STACK_OF(SSL_CIPHER) *ciphers = SSL_get_ciphers(ssl); int any_enabled = 0; for (size_t i = 0; i < sk_SSL_CIPHER_num(ciphers); i++) { const SSL_CIPHER *cipher = sk_SSL_CIPHER_value(ciphers, i); /* 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; } } /* For SSLv3, the SCSV is added. Otherwise the renegotiation extension is * added. */ if (hs->max_version == SSL3_VERSION && !ssl->s3->initial_handshake_complete) { if (!CBB_add_u16(&child, SSL3_CK_SCSV & 0xffff)) { 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; CBB cbb, body; if (!ssl->method->init_message(ssl, &cbb, &body, SSL3_MT_CLIENT_HELLO)) { goto err; } /* Renegotiations do not participate in session resumption. */ int has_session = ssl->session != NULL && !ssl->s3->initial_handshake_complete; 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) || (has_session && !CBB_add_bytes(&child, ssl->session->session_id, ssl->session->session_id_length))) { goto err; } if (SSL_is_dtls(ssl)) { if (!CBB_add_u8_length_prefixed(&body, &child) || !CBB_add_bytes(&child, ssl->d1->cookie, ssl->d1->cookie_len)) { goto err; } } 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))) { goto err; } uint8_t *msg = NULL; size_t len; if (!ssl->method->finish_message(ssl, &cbb, &msg, &len)) { goto err; } /* 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, len)) { OPENSSL_free(msg); goto err; } return ssl->method->add_message(ssl, msg, len); err: CBB_cleanup(&cbb); return 0; } static int ssl3_send_client_hello(SSL_HANDSHAKE *hs) { SSL *const ssl = hs->ssl; /* The handshake buffer is reset on every ClientHello. Notably, in DTLS, we * may send multiple ClientHellos if we receive HelloVerifyRequest. */ if (!SSL_TRANSCRIPT_init(&hs->transcript)) { OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); return -1; } /* Freeze the version range. */ if (!ssl_get_version_range(ssl, &hs->min_version, &hs->max_version)) { return -1; } uint16_t max_wire_version = ssl->method->version_to_wire(hs->max_version); assert(hs->state == SSL3_ST_CW_CLNT_HELLO_A); if (!ssl->s3->have_version) { ssl->version = max_wire_version; } /* 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. */ hs->client_version = max_wire_version; if (hs->max_version >= TLS1_3_VERSION) { hs->client_version = ssl->method->version_to_wire(TLS1_2_VERSION); } /* If the configured session has expired or was created at a disabled * version, drop it. */ if (ssl->session != NULL) { uint16_t session_version; if (ssl->session->is_server || !ssl->method->version_from_wire(&session_version, ssl->session->ssl_version) || (session_version < TLS1_3_VERSION && ssl->session->session_id_length == 0) || ssl->session->not_resumable || !ssl_session_is_time_valid(ssl, ssl->session) || session_version < hs->min_version || session_version > hs->max_version) { ssl_set_session(ssl, NULL); } } /* If resending the ClientHello in DTLS after a HelloVerifyRequest, don't * renegerate the client_random. The random must be reused. */ if ((!SSL_is_dtls(ssl) || !ssl->d1->send_cookie) && !RAND_bytes(ssl->s3->client_random, sizeof(ssl->s3->client_random))) { return -1; } if (!ssl_write_client_hello(hs)) { return -1; } return 1; } static int dtls1_get_hello_verify_request(SSL_HANDSHAKE *hs) { SSL *const ssl = hs->ssl; CBS hello_verify_request, cookie; uint16_t server_version; int ret = ssl->method->ssl_get_message(ssl); if (ret <= 0) { return ret; } if (ssl->s3->tmp.message_type != DTLS1_MT_HELLO_VERIFY_REQUEST) { ssl->d1->send_cookie = 0; ssl->s3->tmp.reuse_message = 1; return 1; } CBS_init(&hello_verify_request, ssl->init_msg, ssl->init_num); 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); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); return -1; } OPENSSL_memcpy(ssl->d1->cookie, CBS_data(&cookie), CBS_len(&cookie)); ssl->d1->cookie_len = CBS_len(&cookie); ssl->d1->send_cookie = 1; return 1; } static int ssl3_get_server_hello(SSL_HANDSHAKE *hs) { SSL *const ssl = hs->ssl; CBS server_hello, server_random, session_id; uint16_t server_wire_version, cipher_suite; uint8_t compression_method; int ret = ssl->method->ssl_get_message(ssl); if (ret <= 0) { uint32_t err = ERR_peek_error(); if (ERR_GET_LIB(err) == ERR_LIB_SSL && ERR_GET_REASON(err) == SSL_R_SSLV3_ALERT_HANDSHAKE_FAILURE) { /* Add a dedicated error code to the queue for a handshake_failure alert * in response to ClientHello. This matches NSS's client behavior and * gives a better error on a (probable) failure to negotiate initial * parameters. Note: this error code comes after the original one. * * See https://crbug.com/446505. */ OPENSSL_PUT_ERROR(SSL, SSL_R_HANDSHAKE_FAILURE_ON_CLIENT_HELLO); } return ret; } if (ssl->s3->tmp.message_type != SSL3_MT_SERVER_HELLO && ssl->s3->tmp.message_type != SSL3_MT_HELLO_RETRY_REQUEST) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE); OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE); return -1; } CBS_init(&server_hello, ssl->init_msg, ssl->init_num); if (!CBS_get_u16(&server_hello, &server_wire_version)) { OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); return -1; } uint16_t server_version; if (!ssl->method->version_from_wire(&server_version, server_wire_version) || server_version < hs->min_version || server_version > hs->max_version) { OPENSSL_PUT_ERROR(SSL, SSL_R_UNSUPPORTED_PROTOCOL); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_PROTOCOL_VERSION); return -1; } assert(ssl->s3->have_version == ssl->s3->initial_handshake_complete); if (!ssl->s3->have_version) { ssl->version = server_wire_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 = 1; } else if (server_wire_version != ssl->version) { OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_SSL_VERSION); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_PROTOCOL_VERSION); return -1; } if (ssl3_protocol_version(ssl) >= TLS1_3_VERSION) { hs->state = SSL_ST_TLS13; hs->do_tls13_handshake = tls13_client_handshake; return 1; } if (hs->early_data_offered) { OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_VERSION_ON_EARLY_DATA); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_PROTOCOL_VERSION); return -1; } ssl_clear_tls13_state(hs); if (!ssl_check_message_type(ssl, SSL3_MT_SERVER_HELLO)) { return -1; } if (!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); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); return -1; } /* Copy over the server random. */ OPENSSL_memcpy(ssl->s3->server_random, CBS_data(&server_random), SSL3_RANDOM_SIZE); /* TODO(davidben): Implement the TLS 1.1 and 1.2 downgrade sentinels once TLS * 1.3 is finalized and we are not implementing a draft version. */ 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 = 1; } else { /* 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 */)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return -1; } /* 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 *c = SSL_get_cipher_by_value(cipher_suite); if (c == NULL) { /* unknown cipher */ OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_CIPHER_RETURNED); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); return -1; } /* The cipher must be allowed in the selected version and enabled. */ uint32_t mask_a, mask_k; ssl_get_client_disabled(ssl, &mask_a, &mask_k); if ((c->algorithm_mkey & mask_k) || (c->algorithm_auth & mask_a) || SSL_CIPHER_get_min_version(c) > ssl3_protocol_version(ssl) || SSL_CIPHER_get_max_version(c) < ssl3_protocol_version(ssl) || !sk_SSL_CIPHER_find(SSL_get_ciphers(ssl), NULL, c)) { OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CIPHER_RETURNED); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); return -1; } if (ssl->session != NULL) { if (ssl->session->ssl_version != ssl->version) { OPENSSL_PUT_ERROR(SSL, SSL_R_OLD_SESSION_VERSION_NOT_RETURNED); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); return -1; } if (ssl->session->cipher != c) { OPENSSL_PUT_ERROR(SSL, SSL_R_OLD_SESSION_CIPHER_NOT_RETURNED); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); return -1; } if (!ssl_session_is_context_valid(ssl, ssl->session)) { /* This is actually a client application bug. */ OPENSSL_PUT_ERROR(SSL, SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); return -1; } } else { hs->new_session->cipher = c; } hs->new_cipher = c; /* Now that the cipher is known, initialize the handshake hash and hash the * ServerHello. */ if (!SSL_TRANSCRIPT_init_hash(&hs->transcript, ssl3_protocol_version(ssl), c->algorithm_prf) || !ssl_hash_current_message(hs)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return -1; } /* 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)) { SSL_TRANSCRIPT_free_buffer(&hs->transcript); } /* Only the NULL compression algorithm is supported. */ if (compression_method != 0) { OPENSSL_PUT_ERROR(SSL, SSL_R_UNSUPPORTED_COMPRESSION_ALGORITHM); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); return -1; } /* TLS extensions */ if (!ssl_parse_serverhello_tlsext(hs, &server_hello)) { OPENSSL_PUT_ERROR(SSL, SSL_R_PARSE_TLSEXT); return -1; } /* 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); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); return -1; } 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); } ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); return -1; } return 1; } static int ssl3_get_server_certificate(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_CERTIFICATE) || !ssl_hash_current_message(hs)) { return -1; } CBS cbs; CBS_init(&cbs, ssl->init_msg, ssl->init_num); uint8_t alert = SSL_AD_DECODE_ERROR; sk_CRYPTO_BUFFER_pop_free(hs->new_session->certs, CRYPTO_BUFFER_free); EVP_PKEY_free(hs->peer_pubkey); hs->peer_pubkey = NULL; hs->new_session->certs = ssl_parse_cert_chain(&alert, &hs->peer_pubkey, NULL, &cbs, ssl->ctx->pool); if (hs->new_session->certs == NULL) { ssl3_send_alert(ssl, SSL3_AL_FATAL, alert); return -1; } if (sk_CRYPTO_BUFFER_num(hs->new_session->certs) == 0 || CBS_len(&cbs) != 0 || !ssl->ctx->x509_method->session_cache_objects(hs->new_session)) { OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); return -1; } if (!ssl_check_leaf_certificate( hs, hs->peer_pubkey, sk_CRYPTO_BUFFER_value(hs->new_session->certs, 0))) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); return -1; } /* Disallow the server certificate from changing during a renegotiation. See * https://mitls.org/pages/attacks/3SHAKE. We never resume on renegotiation, * so this check is sufficient. */ if (ssl->s3->established_session != NULL) { if (sk_CRYPTO_BUFFER_num(ssl->s3->established_session->certs) != sk_CRYPTO_BUFFER_num(hs->new_session->certs)) { OPENSSL_PUT_ERROR(SSL, SSL_R_SERVER_CERT_CHANGED); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); return -1; } for (size_t i = 0; i < sk_CRYPTO_BUFFER_num(hs->new_session->certs); i++) { const CRYPTO_BUFFER *old_cert = sk_CRYPTO_BUFFER_value(ssl->s3->established_session->certs, i); const CRYPTO_BUFFER *new_cert = sk_CRYPTO_BUFFER_value(hs->new_session->certs, i); if (CRYPTO_BUFFER_len(old_cert) != CRYPTO_BUFFER_len(new_cert) || OPENSSL_memcmp(CRYPTO_BUFFER_data(old_cert), CRYPTO_BUFFER_data(new_cert), CRYPTO_BUFFER_len(old_cert)) != 0) { OPENSSL_PUT_ERROR(SSL, SSL_R_SERVER_CERT_CHANGED); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); return -1; } } } return 1; } static int ssl3_get_cert_status(SSL_HANDSHAKE *hs) { SSL *const ssl = hs->ssl; int ret = ssl->method->ssl_get_message(ssl); if (ret <= 0) { return ret; } if (ssl->s3->tmp.message_type != SSL3_MT_CERTIFICATE_STATUS) { /* A server may send status_request in ServerHello and then change * its mind about sending CertificateStatus. */ ssl->s3->tmp.reuse_message = 1; return 1; } if (!ssl_hash_current_message(hs)) { return -1; } CBS certificate_status, ocsp_response; uint8_t status_type; CBS_init(&certificate_status, ssl->init_msg, ssl->init_num); 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); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); return -1; } if (!CBS_stow(&ocsp_response, &hs->new_session->ocsp_response, &hs->new_session->ocsp_response_length)) { OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return -1; } return 1; } static int ssl3_verify_server_cert(SSL_HANDSHAKE *hs) { SSL *const ssl = hs->ssl; if (!ssl->ctx->x509_method->session_verify_cert_chain(hs->new_session, ssl)) { return -1; } return 1; } static int ssl3_get_server_key_exchange(SSL_HANDSHAKE *hs) { SSL *const ssl = hs->ssl; EC_KEY *ecdh = NULL; EC_POINT *srvr_ecpoint = NULL; int ret = ssl->method->ssl_get_message(ssl); if (ret <= 0) { return ret; } if (ssl->s3->tmp.message_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); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE); return -1; } ssl->s3->tmp.reuse_message = 1; return 1; } if (!ssl_hash_current_message(hs)) { return -1; } /* Retain a copy of the original CBS to compute the signature over. */ CBS server_key_exchange; CBS_init(&server_key_exchange, ssl->init_msg, ssl->init_num); CBS server_key_exchange_orig = server_key_exchange; uint32_t alg_k = hs->new_cipher->algorithm_mkey; uint32_t alg_a = hs->new_cipher->algorithm_auth; 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); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); goto err; } /* Store PSK identity hint for later use, hint is used in * ssl3_send_client_key_exchange. 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); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); goto err; } /* 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. */ if (CBS_len(&psk_identity_hint) != 0 && !CBS_strdup(&psk_identity_hint, &hs->peer_psk_identity_hint)) { OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); goto err; } } 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); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); goto err; } hs->new_session->group_id = group_id; /* Ensure the group is consistent with preferences. */ if (!tls1_check_group_id(ssl, group_id)) { OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CURVE); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); goto err; } /* Initialize ECDH and save the peer public key for later. */ if (!SSL_ECDH_CTX_init(&hs->ecdh_ctx, group_id) || !CBS_stow(&point, &hs->peer_key, &hs->peer_key_len)) { goto err; } } else if (!(alg_k & SSL_kPSK)) { OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE); goto err; } /* At this point, |server_key_exchange| contains the signature, if any, while * |server_key_exchange_orig| contains the entire message. From that, derive * a CBS containing just the parameter. */ CBS parameter; CBS_init(¶meter, CBS_data(&server_key_exchange_orig), CBS_len(&server_key_exchange_orig) - 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 (ssl3_protocol_version(ssl) >= TLS1_2_VERSION) { if (!CBS_get_u16(&server_key_exchange, &signature_algorithm)) { OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); goto err; } uint8_t alert = SSL_AD_DECODE_ERROR; if (!tls12_check_peer_sigalg(ssl, &alert, signature_algorithm)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, alert); goto err; } hs->new_session->peer_signature_algorithm = signature_algorithm; } else if (!tls1_get_legacy_signature_algorithm(&signature_algorithm, hs->peer_pubkey)) { OPENSSL_PUT_ERROR(SSL, SSL_R_PEER_ERROR_UNSUPPORTED_CERTIFICATE_TYPE); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNSUPPORTED_CERTIFICATE); goto err; } /* 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); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); goto err; } CBB transcript; uint8_t *transcript_data; size_t transcript_len; if (!CBB_init(&transcript, 2*SSL3_RANDOM_SIZE + CBS_len(¶meter)) || !CBB_add_bytes(&transcript, ssl->s3->client_random, SSL3_RANDOM_SIZE) || !CBB_add_bytes(&transcript, ssl->s3->server_random, SSL3_RANDOM_SIZE) || !CBB_add_bytes(&transcript, CBS_data(¶meter), CBS_len(¶meter)) || !CBB_finish(&transcript, &transcript_data, &transcript_len)) { CBB_cleanup(&transcript); OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); goto err; } int sig_ok = ssl_public_key_verify( ssl, CBS_data(&signature), CBS_len(&signature), signature_algorithm, hs->peer_pubkey, transcript_data, transcript_len); OPENSSL_free(transcript_data); #if defined(BORINGSSL_UNSAFE_FUZZER_MODE) sig_ok = 1; ERR_clear_error(); #endif if (!sig_ok) { /* bad signature */ OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_SIGNATURE); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECRYPT_ERROR); goto err; } } 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); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); goto err; } } return 1; err: EC_POINT_free(srvr_ecpoint); EC_KEY_free(ecdh); return -1; } static int ssl3_get_certificate_request(SSL_HANDSHAKE *hs) { SSL *const ssl = hs->ssl; int msg_ret = ssl->method->ssl_get_message(ssl); if (msg_ret <= 0) { return msg_ret; } if (ssl->s3->tmp.message_type == SSL3_MT_SERVER_HELLO_DONE) { ssl->s3->tmp.reuse_message = 1; /* If we get here we don't need the handshake buffer as we won't be doing * client auth. */ SSL_TRANSCRIPT_free_buffer(&hs->transcript); return 1; } if (!ssl_check_message_type(ssl, SSL3_MT_CERTIFICATE_REQUEST) || !ssl_hash_current_message(hs)) { return -1; } CBS cbs; CBS_init(&cbs, ssl->init_msg, ssl->init_num); /* Get the certificate types. */ CBS certificate_types; if (!CBS_get_u8_length_prefixed(&cbs, &certificate_types)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); return -1; } if (!CBS_stow(&certificate_types, &hs->certificate_types, &hs->num_certificate_types)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return -1; } if (ssl3_protocol_version(ssl) >= TLS1_2_VERSION) { CBS supported_signature_algorithms; if (!CBS_get_u16_length_prefixed(&cbs, &supported_signature_algorithms) || !tls1_parse_peer_sigalgs(hs, &supported_signature_algorithms)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); return -1; } } uint8_t alert = SSL_AD_DECODE_ERROR; STACK_OF(CRYPTO_BUFFER) *ca_names = ssl_parse_client_CA_list(ssl, &alert, &cbs); if (ca_names == NULL) { ssl3_send_alert(ssl, SSL3_AL_FATAL, alert); return -1; } if (CBS_len(&cbs) != 0) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); sk_CRYPTO_BUFFER_pop_free(ca_names, CRYPTO_BUFFER_free); OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); return -1; } hs->cert_request = 1; sk_CRYPTO_BUFFER_pop_free(hs->ca_names, CRYPTO_BUFFER_free); hs->ca_names = ca_names; ssl->ctx->x509_method->hs_flush_cached_ca_names(hs); return 1; } static int ssl3_get_server_hello_done(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_SERVER_HELLO_DONE) || !ssl_hash_current_message(hs)) { return -1; } /* ServerHelloDone is empty. */ if (ssl->init_num > 0) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); return -1; } return 1; } static int ssl3_send_client_certificate(SSL_HANDSHAKE *hs) { SSL *const ssl = hs->ssl; /* Call cert_cb to update the certificate. */ if (ssl->cert->cert_cb) { int ret = ssl->cert->cert_cb(ssl, ssl->cert->cert_cb_arg); if (ret < 0) { ssl->rwstate = SSL_X509_LOOKUP; return -1; } if (ret == 0) { OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_CB_ERROR); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return -1; } } if (!ssl_has_certificate(ssl)) { /* Without a client certificate, the handshake buffer may be released. */ SSL_TRANSCRIPT_free_buffer(&hs->transcript); /* In SSL 3.0, the Certificate message is replaced with a warning alert. */ if (ssl->version == SSL3_VERSION) { if (!ssl->method->add_alert(ssl, SSL3_AL_WARNING, SSL_AD_NO_CERTIFICATE)) { return -1; } return 1; } } if (!ssl_on_certificate_selected(hs) || !ssl3_output_cert_chain(ssl)) { return -1; } return 1; } OPENSSL_COMPILE_ASSERT(sizeof(size_t) >= sizeof(unsigned), SIZE_T_IS_SMALLER_THAN_UNSIGNED); static int ssl3_send_client_key_exchange(SSL_HANDSHAKE *hs) { SSL *const ssl = hs->ssl; uint8_t *pms = NULL; size_t pms_len = 0; CBB cbb, body; if (!ssl->method->init_message(ssl, &cbb, &body, SSL3_MT_CLIENT_KEY_EXCHANGE)) { goto err; } 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 (ssl->psk_client_callback == NULL) { OPENSSL_PUT_ERROR(SSL, SSL_R_PSK_NO_CLIENT_CB); goto err; } char identity[PSK_MAX_IDENTITY_LEN + 1]; OPENSSL_memset(identity, 0, sizeof(identity)); psk_len = ssl->psk_client_callback(ssl, hs->peer_psk_identity_hint, identity, sizeof(identity), psk, sizeof(psk)); if (psk_len == 0) { OPENSSL_PUT_ERROR(SSL, SSL_R_PSK_IDENTITY_NOT_FOUND); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); goto err; } assert(psk_len <= PSK_MAX_PSK_LEN); OPENSSL_free(hs->new_session->psk_identity); hs->new_session->psk_identity = BUF_strdup(identity); if (hs->new_session->psk_identity == NULL) { OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); goto err; } /* 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)) { goto err; } } /* Depending on the key exchange method, compute |pms| and |pms_len|. */ if (alg_k & SSL_kRSA) { pms_len = SSL_MAX_MASTER_KEY_LENGTH; pms = OPENSSL_malloc(pms_len); if (pms == NULL) { OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); goto err; } RSA *rsa = EVP_PKEY_get0_RSA(hs->peer_pubkey); if (rsa == NULL) { OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); goto err; } pms[0] = hs->client_version >> 8; pms[1] = hs->client_version & 0xff; if (!RAND_bytes(&pms[2], SSL_MAX_MASTER_KEY_LENGTH - 2)) { goto err; } CBB child, *enc_pms = &body; size_t enc_pms_len; /* In TLS, there is a length prefix. */ if (ssl->version > SSL3_VERSION) { if (!CBB_add_u16_length_prefixed(&body, &child)) { goto err; } enc_pms = &child; } uint8_t *ptr; if (!CBB_reserve(enc_pms, &ptr, RSA_size(rsa)) || !RSA_encrypt(rsa, &enc_pms_len, ptr, RSA_size(rsa), pms, pms_len, RSA_PKCS1_PADDING) || !CBB_did_write(enc_pms, enc_pms_len) || !CBB_flush(&body)) { goto err; } } else if (alg_k & SSL_kECDHE) { /* Generate a keypair and serialize the public half. */ CBB child; if (!CBB_add_u8_length_prefixed(&body, &child)) { goto err; } /* Compute the premaster. */ uint8_t alert = SSL_AD_DECODE_ERROR; if (!SSL_ECDH_CTX_accept(&hs->ecdh_ctx, &child, &pms, &pms_len, &alert, hs->peer_key, hs->peer_key_len)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, alert); goto err; } if (!CBB_flush(&body)) { goto err; } /* The key exchange state may now be discarded. */ SSL_ECDH_CTX_cleanup(&hs->ecdh_ctx); OPENSSL_free(hs->peer_key); hs->peer_key = NULL; hs->peer_key_len = 0; } 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. */ pms_len = psk_len; pms = OPENSSL_malloc(pms_len); if (pms == NULL) { OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); goto err; } OPENSSL_memset(pms, 0, pms_len); } else { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); goto err; } /* For a PSK cipher suite, other_secret is combined with the pre-shared * key. */ if (alg_a & SSL_aPSK) { CBB pms_cbb, child; uint8_t *new_pms; size_t new_pms_len; CBB_zero(&pms_cbb); if (!CBB_init(&pms_cbb, 2 + psk_len + 2 + pms_len) || !CBB_add_u16_length_prefixed(&pms_cbb, &child) || !CBB_add_bytes(&child, pms, pms_len) || !CBB_add_u16_length_prefixed(&pms_cbb, &child) || !CBB_add_bytes(&child, psk, psk_len) || !CBB_finish(&pms_cbb, &new_pms, &new_pms_len)) { CBB_cleanup(&pms_cbb); OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); goto err; } OPENSSL_cleanse(pms, pms_len); OPENSSL_free(pms); pms = new_pms; pms_len = new_pms_len; } /* The message must be added to the finished hash before calculating the * master secret. */ if (!ssl_add_message_cbb(ssl, &cbb)) { goto err; } hs->new_session->master_key_length = tls1_generate_master_secret( hs, hs->new_session->master_key, pms, pms_len); if (hs->new_session->master_key_length == 0) { goto err; } hs->new_session->extended_master_secret = hs->extended_master_secret; OPENSSL_cleanse(pms, pms_len); OPENSSL_free(pms); return 1; err: CBB_cleanup(&cbb); if (pms != NULL) { OPENSSL_cleanse(pms, pms_len); OPENSSL_free(pms); } return -1; } static int ssl3_send_cert_verify(SSL_HANDSHAKE *hs) { SSL *const ssl = hs->ssl; assert(ssl_has_private_key(ssl)); CBB cbb, body, child; if (!ssl->method->init_message(ssl, &cbb, &body, SSL3_MT_CERTIFICATE_VERIFY)) { goto err; } uint16_t signature_algorithm; if (!tls1_choose_signature_algorithm(hs, &signature_algorithm)) { goto err; } if (ssl3_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); goto err; } } /* Set aside space for the signature. */ const size_t max_sig_len = EVP_PKEY_size(hs->local_pubkey); uint8_t *ptr; if (!CBB_add_u16_length_prefixed(&body, &child) || !CBB_reserve(&child, &ptr, max_sig_len)) { goto err; } size_t sig_len = max_sig_len; /* The SSL3 construction for CertificateVerify does not decompose into a * single final digest and signature, and must be special-cased. */ if (ssl3_protocol_version(ssl) == SSL3_VERSION) { if (ssl->cert->key_method != NULL) { OPENSSL_PUT_ERROR(SSL, SSL_R_UNSUPPORTED_PROTOCOL_FOR_CUSTOM_KEY); goto err; } uint8_t digest[EVP_MAX_MD_SIZE]; size_t digest_len; if (!SSL_TRANSCRIPT_ssl3_cert_verify_hash(&hs->transcript, digest, &digest_len, hs->new_session, signature_algorithm)) { goto err; } EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new(ssl->cert->privatekey, NULL); int ok = pctx != NULL && EVP_PKEY_sign_init(pctx) && EVP_PKEY_sign(pctx, ptr, &sig_len, digest, digest_len); EVP_PKEY_CTX_free(pctx); if (!ok) { goto err; } } else { switch (ssl_private_key_sign(hs, ptr, &sig_len, max_sig_len, signature_algorithm, (const uint8_t *)hs->transcript.buffer->data, hs->transcript.buffer->length)) { case ssl_private_key_success: break; case ssl_private_key_failure: goto err; case ssl_private_key_retry: ssl->rwstate = SSL_PRIVATE_KEY_OPERATION; goto err; } } if (!CBB_did_write(&child, sig_len) || !ssl_add_message_cbb(ssl, &cbb)) { goto err; } /* The handshake buffer is no longer necessary. */ SSL_TRANSCRIPT_free_buffer(&hs->transcript); return 1; err: CBB_cleanup(&cbb); return -1; } static int ssl3_send_next_proto(SSL_HANDSHAKE *hs) { SSL *const ssl = hs->ssl; static const uint8_t kZero[32] = {0}; size_t padding_len = 32 - ((ssl->s3->next_proto_negotiated_len + 2) % 32); CBB cbb, body, child; if (!ssl->method->init_message(ssl, &cbb, &body, SSL3_MT_NEXT_PROTO) || !CBB_add_u8_length_prefixed(&body, &child) || !CBB_add_bytes(&child, ssl->s3->next_proto_negotiated, ssl->s3->next_proto_negotiated_len) || !CBB_add_u8_length_prefixed(&body, &child) || !CBB_add_bytes(&child, kZero, padding_len) || !ssl_add_message_cbb(ssl, &cbb)) { OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); CBB_cleanup(&cbb); return -1; } return 1; } static int ssl3_send_channel_id(SSL_HANDSHAKE *hs) { SSL *const ssl = hs->ssl; if (!ssl_do_channel_id_callback(ssl)) { return -1; } if (ssl->tlsext_channel_id_private == NULL) { ssl->rwstate = SSL_CHANNEL_ID_LOOKUP; return -1; } CBB cbb, body; if (!ssl->method->init_message(ssl, &cbb, &body, SSL3_MT_CHANNEL_ID) || !tls1_write_channel_id(hs, &body) || !ssl_add_message_cbb(ssl, &cbb)) { OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); CBB_cleanup(&cbb); return -1; } return 1; } static int ssl3_get_new_session_ticket(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_NEW_SESSION_TICKET) || !ssl_hash_current_message(hs)) { return -1; } CBS new_session_ticket, ticket; uint32_t tlsext_tick_lifetime_hint; CBS_init(&new_session_ticket, ssl->init_msg, ssl->init_num); if (!CBS_get_u32(&new_session_ticket, &tlsext_tick_lifetime_hint) || !CBS_get_u16_length_prefixed(&new_session_ticket, &ticket) || CBS_len(&new_session_ticket) != 0) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); return -1; } 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 = 0; return 1; } int session_renewed = ssl->session != NULL; SSL_SESSION *session = hs->new_session; if (session_renewed) { /* 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. */ session = SSL_SESSION_dup(ssl->session, SSL_SESSION_INCLUDE_NONAUTH); if (session == NULL) { /* This should never happen. */ OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); goto err; } } /* |tlsext_tick_lifetime_hint| is measured from when the ticket was issued. */ ssl_session_rebase_time(ssl, session); if (!CBS_stow(&ticket, &session->tlsext_tick, &session->tlsext_ticklen)) { OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); goto err; } session->tlsext_tick_lifetime_hint = tlsext_tick_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)) { goto err; } if (session_renewed) { session->not_resumable = 0; SSL_SESSION_free(ssl->session); ssl->session = session; } return 1; err: if (session_renewed) { SSL_SESSION_free(session); } return -1; }