1 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com) 2 * All rights reserved. 3 * 4 * This package is an SSL implementation written 5 * by Eric Young (eay (at) cryptsoft.com). 6 * The implementation was written so as to conform with Netscapes SSL. 7 * 8 * This library is free for commercial and non-commercial use as long as 9 * the following conditions are aheared to. The following conditions 10 * apply to all code found in this distribution, be it the RC4, RSA, 11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 12 * included with this distribution is covered by the same copyright terms 13 * except that the holder is Tim Hudson (tjh (at) cryptsoft.com). 14 * 15 * Copyright remains Eric Young's, and as such any Copyright notices in 16 * the code are not to be removed. 17 * If this package is used in a product, Eric Young should be given attribution 18 * as the author of the parts of the library used. 19 * This can be in the form of a textual message at program startup or 20 * in documentation (online or textual) provided with the package. 21 * 22 * Redistribution and use in source and binary forms, with or without 23 * modification, are permitted provided that the following conditions 24 * are met: 25 * 1. Redistributions of source code must retain the copyright 26 * notice, this list of conditions and the following disclaimer. 27 * 2. Redistributions in binary form must reproduce the above copyright 28 * notice, this list of conditions and the following disclaimer in the 29 * documentation and/or other materials provided with the distribution. 30 * 3. All advertising materials mentioning features or use of this software 31 * must display the following acknowledgement: 32 * "This product includes cryptographic software written by 33 * Eric Young (eay (at) cryptsoft.com)" 34 * The word 'cryptographic' can be left out if the rouines from the library 35 * being used are not cryptographic related :-). 36 * 4. If you include any Windows specific code (or a derivative thereof) from 37 * the apps directory (application code) you must include an acknowledgement: 38 * "This product includes software written by Tim Hudson (tjh (at) cryptsoft.com)" 39 * 40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 50 * SUCH DAMAGE. 51 * 52 * The licence and distribution terms for any publically available version or 53 * derivative of this code cannot be changed. i.e. this code cannot simply be 54 * copied and put under another distribution licence 55 * [including the GNU Public Licence.] 56 */ 57 /* ==================================================================== 58 * Copyright (c) 1998-2007 The OpenSSL Project. All rights reserved. 59 * 60 * Redistribution and use in source and binary forms, with or without 61 * modification, are permitted provided that the following conditions 62 * are met: 63 * 64 * 1. Redistributions of source code must retain the above copyright 65 * notice, this list of conditions and the following disclaimer. 66 * 67 * 2. Redistributions in binary form must reproduce the above copyright 68 * notice, this list of conditions and the following disclaimer in 69 * the documentation and/or other materials provided with the 70 * distribution. 71 * 72 * 3. All advertising materials mentioning features or use of this 73 * software must display the following acknowledgment: 74 * "This product includes software developed by the OpenSSL Project 75 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 76 * 77 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 78 * endorse or promote products derived from this software without 79 * prior written permission. For written permission, please contact 80 * openssl-core (at) openssl.org. 81 * 82 * 5. Products derived from this software may not be called "OpenSSL" 83 * nor may "OpenSSL" appear in their names without prior written 84 * permission of the OpenSSL Project. 85 * 86 * 6. Redistributions of any form whatsoever must retain the following 87 * acknowledgment: 88 * "This product includes software developed by the OpenSSL Project 89 * for use in the OpenSSL Toolkit (http://www.openssl.org/)" 90 * 91 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 92 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 93 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 94 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 95 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 96 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 97 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 98 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 99 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 100 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 101 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 102 * OF THE POSSIBILITY OF SUCH DAMAGE. 103 * ==================================================================== 104 * 105 * This product includes cryptographic software written by Eric Young 106 * (eay (at) cryptsoft.com). This product includes software written by Tim 107 * Hudson (tjh (at) cryptsoft.com). 108 * 109 */ 110 /* ==================================================================== 111 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. 112 * 113 * Portions of the attached software ("Contribution") are developed by 114 * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project. 115 * 116 * The Contribution is licensed pursuant to the OpenSSL open source 117 * license provided above. 118 * 119 * ECC cipher suite support in OpenSSL originally written by 120 * Vipul Gupta and Sumit Gupta of Sun Microsystems Laboratories. 121 * 122 */ 123 /* ==================================================================== 124 * Copyright 2005 Nokia. All rights reserved. 125 * 126 * The portions of the attached software ("Contribution") is developed by 127 * Nokia Corporation and is licensed pursuant to the OpenSSL open source 128 * license. 129 * 130 * The Contribution, originally written by Mika Kousa and Pasi Eronen of 131 * Nokia Corporation, consists of the "PSK" (Pre-Shared Key) ciphersuites 132 * support (see RFC 4279) to OpenSSL. 133 * 134 * No patent licenses or other rights except those expressly stated in 135 * the OpenSSL open source license shall be deemed granted or received 136 * expressly, by implication, estoppel, or otherwise. 137 * 138 * No assurances are provided by Nokia that the Contribution does not 139 * infringe the patent or other intellectual property rights of any third 140 * party or that the license provides you with all the necessary rights 141 * to make use of the Contribution. 142 * 143 * THE SOFTWARE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. IN 144 * ADDITION TO THE DISCLAIMERS INCLUDED IN THE LICENSE, NOKIA 145 * SPECIFICALLY DISCLAIMS ANY LIABILITY FOR CLAIMS BROUGHT BY YOU OR ANY 146 * OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OR 147 * OTHERWISE. 148 */ 149 150 #include <openssl/ssl.h> 151 152 #include <assert.h> 153 #include <limits.h> 154 #include <string.h> 155 156 #include <utility> 157 158 #include <openssl/aead.h> 159 #include <openssl/bn.h> 160 #include <openssl/buf.h> 161 #include <openssl/bytestring.h> 162 #include <openssl/ec_key.h> 163 #include <openssl/ecdsa.h> 164 #include <openssl/err.h> 165 #include <openssl/evp.h> 166 #include <openssl/md5.h> 167 #include <openssl/mem.h> 168 #include <openssl/rand.h> 169 170 #include "../crypto/internal.h" 171 #include "internal.h" 172 173 174 namespace bssl { 175 176 enum ssl_client_hs_state_t { 177 state_start_connect = 0, 178 state_enter_early_data, 179 state_read_hello_verify_request, 180 state_read_server_hello, 181 state_tls13, 182 state_read_server_certificate, 183 state_read_certificate_status, 184 state_verify_server_certificate, 185 state_read_server_key_exchange, 186 state_read_certificate_request, 187 state_read_server_hello_done, 188 state_send_client_certificate, 189 state_send_client_key_exchange, 190 state_send_client_certificate_verify, 191 state_send_client_finished, 192 state_finish_flight, 193 state_read_session_ticket, 194 state_process_change_cipher_spec, 195 state_read_server_finished, 196 state_finish_client_handshake, 197 state_done, 198 }; 199 200 // ssl_get_client_disabled sets |*out_mask_a| and |*out_mask_k| to masks of 201 // disabled algorithms. 202 static void ssl_get_client_disabled(SSL *ssl, uint32_t *out_mask_a, 203 uint32_t *out_mask_k) { 204 *out_mask_a = 0; 205 *out_mask_k = 0; 206 207 // PSK requires a client callback. 208 if (ssl->psk_client_callback == NULL) { 209 *out_mask_a |= SSL_aPSK; 210 *out_mask_k |= SSL_kPSK; 211 } 212 } 213 214 static int ssl_write_client_cipher_list(SSL_HANDSHAKE *hs, CBB *out) { 215 SSL *const ssl = hs->ssl; 216 uint32_t mask_a, mask_k; 217 ssl_get_client_disabled(ssl, &mask_a, &mask_k); 218 219 CBB child; 220 if (!CBB_add_u16_length_prefixed(out, &child)) { 221 return 0; 222 } 223 224 // Add a fake cipher suite. See draft-davidben-tls-grease-01. 225 if (ssl->ctx->grease_enabled && 226 !CBB_add_u16(&child, ssl_get_grease_value(hs, ssl_grease_cipher))) { 227 return 0; 228 } 229 230 // Add TLS 1.3 ciphers. Order ChaCha20-Poly1305 relative to AES-GCM based on 231 // hardware support. 232 if (hs->max_version >= TLS1_3_VERSION) { 233 if (!EVP_has_aes_hardware() && 234 !CBB_add_u16(&child, TLS1_CK_CHACHA20_POLY1305_SHA256 & 0xffff)) { 235 return 0; 236 } 237 if (!CBB_add_u16(&child, TLS1_CK_AES_128_GCM_SHA256 & 0xffff) || 238 !CBB_add_u16(&child, TLS1_CK_AES_256_GCM_SHA384 & 0xffff)) { 239 return 0; 240 } 241 if (EVP_has_aes_hardware() && 242 !CBB_add_u16(&child, TLS1_CK_CHACHA20_POLY1305_SHA256 & 0xffff)) { 243 return 0; 244 } 245 } 246 247 if (hs->min_version < TLS1_3_VERSION) { 248 int any_enabled = 0; 249 for (const SSL_CIPHER *cipher : SSL_get_ciphers(ssl)) { 250 // Skip disabled ciphers 251 if ((cipher->algorithm_mkey & mask_k) || 252 (cipher->algorithm_auth & mask_a)) { 253 continue; 254 } 255 if (SSL_CIPHER_get_min_version(cipher) > hs->max_version || 256 SSL_CIPHER_get_max_version(cipher) < hs->min_version) { 257 continue; 258 } 259 any_enabled = 1; 260 if (!CBB_add_u16(&child, ssl_cipher_get_value(cipher))) { 261 return 0; 262 } 263 } 264 265 // If all ciphers were disabled, return the error to the caller. 266 if (!any_enabled && hs->max_version < TLS1_3_VERSION) { 267 OPENSSL_PUT_ERROR(SSL, SSL_R_NO_CIPHERS_AVAILABLE); 268 return 0; 269 } 270 } 271 272 // For SSLv3, the SCSV is added. Otherwise the renegotiation extension is 273 // added. 274 if (hs->max_version == SSL3_VERSION && 275 !ssl->s3->initial_handshake_complete) { 276 if (!CBB_add_u16(&child, SSL3_CK_SCSV & 0xffff)) { 277 return 0; 278 } 279 } 280 281 if (ssl->mode & SSL_MODE_SEND_FALLBACK_SCSV) { 282 if (!CBB_add_u16(&child, SSL3_CK_FALLBACK_SCSV & 0xffff)) { 283 return 0; 284 } 285 } 286 287 return CBB_flush(out); 288 } 289 290 int ssl_write_client_hello(SSL_HANDSHAKE *hs) { 291 SSL *const ssl = hs->ssl; 292 ScopedCBB cbb; 293 CBB body; 294 if (!ssl->method->init_message(ssl, cbb.get(), &body, SSL3_MT_CLIENT_HELLO)) { 295 return 0; 296 } 297 298 CBB child; 299 if (!CBB_add_u16(&body, hs->client_version) || 300 !CBB_add_bytes(&body, ssl->s3->client_random, SSL3_RANDOM_SIZE) || 301 !CBB_add_u8_length_prefixed(&body, &child)) { 302 return 0; 303 } 304 305 // Do not send a session ID on renegotiation. 306 if (!ssl->s3->initial_handshake_complete && 307 !CBB_add_bytes(&child, hs->session_id, hs->session_id_len)) { 308 return 0; 309 } 310 311 if (SSL_is_dtls(ssl)) { 312 if (!CBB_add_u8_length_prefixed(&body, &child) || 313 !CBB_add_bytes(&child, ssl->d1->cookie, ssl->d1->cookie_len)) { 314 return 0; 315 } 316 } 317 318 size_t header_len = 319 SSL_is_dtls(ssl) ? DTLS1_HM_HEADER_LENGTH : SSL3_HM_HEADER_LENGTH; 320 if (!ssl_write_client_cipher_list(hs, &body) || 321 !CBB_add_u8(&body, 1 /* one compression method */) || 322 !CBB_add_u8(&body, 0 /* null compression */) || 323 !ssl_add_clienthello_tlsext(hs, &body, header_len + CBB_len(&body))) { 324 return 0; 325 } 326 327 Array<uint8_t> msg; 328 if (!ssl->method->finish_message(ssl, cbb.get(), &msg)) { 329 return 0; 330 } 331 332 // Now that the length prefixes have been computed, fill in the placeholder 333 // PSK binder. 334 if (hs->needs_psk_binder && 335 !tls13_write_psk_binder(hs, msg.data(), msg.size())) { 336 return 0; 337 } 338 339 return ssl->method->add_message(ssl, std::move(msg)); 340 } 341 342 static int parse_server_version(SSL_HANDSHAKE *hs, uint16_t *out, 343 const SSLMessage &msg) { 344 SSL *const ssl = hs->ssl; 345 if (msg.type != SSL3_MT_SERVER_HELLO && 346 msg.type != SSL3_MT_HELLO_RETRY_REQUEST) { 347 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE); 348 OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE); 349 return 0; 350 } 351 352 CBS server_hello = msg.body; 353 if (!CBS_get_u16(&server_hello, out)) { 354 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 355 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 356 return 0; 357 } 358 359 // The server version may also be in the supported_versions extension if 360 // applicable. 361 if (msg.type != SSL3_MT_SERVER_HELLO || *out != TLS1_2_VERSION) { 362 return 1; 363 } 364 365 uint8_t sid_length; 366 if (!CBS_skip(&server_hello, SSL3_RANDOM_SIZE) || 367 !CBS_get_u8(&server_hello, &sid_length) || 368 !CBS_skip(&server_hello, sid_length + 2 /* cipher_suite */ + 369 1 /* compression_method */)) { 370 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 371 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 372 return 0; 373 } 374 375 // The extensions block may not be present. 376 if (CBS_len(&server_hello) == 0) { 377 return 1; 378 } 379 380 CBS extensions; 381 if (!CBS_get_u16_length_prefixed(&server_hello, &extensions) || 382 CBS_len(&server_hello) != 0) { 383 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 384 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 385 return 0; 386 } 387 388 bool have_supported_versions; 389 CBS supported_versions; 390 const SSL_EXTENSION_TYPE ext_types[] = { 391 {TLSEXT_TYPE_supported_versions, &have_supported_versions, 392 &supported_versions}, 393 }; 394 395 uint8_t alert = SSL_AD_DECODE_ERROR; 396 if (!ssl_parse_extensions(&extensions, &alert, ext_types, 397 OPENSSL_ARRAY_SIZE(ext_types), 398 1 /* ignore unknown */)) { 399 ssl_send_alert(ssl, SSL3_AL_FATAL, alert); 400 return 0; 401 } 402 403 if (have_supported_versions && 404 (!CBS_get_u16(&supported_versions, out) || 405 CBS_len(&supported_versions) != 0)) { 406 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 407 return 0; 408 } 409 410 return 1; 411 } 412 413 static enum ssl_hs_wait_t do_start_connect(SSL_HANDSHAKE *hs) { 414 SSL *const ssl = hs->ssl; 415 416 ssl_do_info_callback(ssl, SSL_CB_HANDSHAKE_START, 1); 417 // |session_reused| must be reset in case this is a renegotiation. 418 ssl->s3->session_reused = false; 419 420 // Freeze the version range. 421 if (!ssl_get_version_range(ssl, &hs->min_version, &hs->max_version)) { 422 return ssl_hs_error; 423 } 424 425 // SSL 3.0 ClientHellos should use SSL 3.0 not TLS 1.0, for the record-layer 426 // version. 427 if (hs->max_version == SSL3_VERSION) { 428 ssl->s3->aead_write_ctx->SetVersionIfNullCipher(SSL3_VERSION); 429 } 430 431 // Always advertise the ClientHello version from the original maximum version, 432 // even on renegotiation. The static RSA key exchange uses this field, and 433 // some servers fail when it changes across handshakes. 434 if (SSL_is_dtls(hs->ssl)) { 435 hs->client_version = 436 hs->max_version >= TLS1_2_VERSION ? DTLS1_2_VERSION : DTLS1_VERSION; 437 } else { 438 hs->client_version = 439 hs->max_version >= TLS1_2_VERSION ? TLS1_2_VERSION : hs->max_version; 440 } 441 442 // If the configured session has expired or was created at a disabled 443 // version, drop it. 444 if (ssl->session != NULL) { 445 if (ssl->session->is_server || 446 !ssl_supports_version(hs, ssl->session->ssl_version) || 447 (ssl->session->session_id_length == 0 && 448 ssl->session->tlsext_ticklen == 0) || 449 ssl->session->not_resumable || 450 !ssl_session_is_time_valid(ssl, ssl->session)) { 451 ssl_set_session(ssl, NULL); 452 } 453 } 454 455 if (!RAND_bytes(ssl->s3->client_random, sizeof(ssl->s3->client_random))) { 456 return ssl_hs_error; 457 } 458 459 // Initialize a random session ID for the experimental TLS 1.3 variant 460 // requiring a session id. 461 if (ssl->session != nullptr && 462 !ssl->s3->initial_handshake_complete && 463 ssl->session->session_id_length > 0) { 464 hs->session_id_len = ssl->session->session_id_length; 465 OPENSSL_memcpy(hs->session_id, ssl->session->session_id, 466 hs->session_id_len); 467 } else if (hs->max_version >= TLS1_3_VERSION) { 468 hs->session_id_len = sizeof(hs->session_id); 469 if (!RAND_bytes(hs->session_id, hs->session_id_len)) { 470 return ssl_hs_error; 471 } 472 } 473 474 if (!ssl_write_client_hello(hs)) { 475 return ssl_hs_error; 476 } 477 478 hs->state = state_enter_early_data; 479 return ssl_hs_flush; 480 } 481 482 static enum ssl_hs_wait_t do_enter_early_data(SSL_HANDSHAKE *hs) { 483 SSL *const ssl = hs->ssl; 484 485 if (SSL_is_dtls(ssl)) { 486 hs->state = state_read_hello_verify_request; 487 return ssl_hs_ok; 488 } 489 490 if (!hs->early_data_offered) { 491 hs->state = state_read_server_hello; 492 return ssl_hs_ok; 493 } 494 495 ssl->s3->aead_write_ctx->SetVersionIfNullCipher(ssl->session->ssl_version); 496 if (!ssl->method->add_change_cipher_spec(ssl)) { 497 return ssl_hs_error; 498 } 499 500 if (!tls13_init_early_key_schedule(hs, ssl->session->master_key, 501 ssl->session->master_key_length) || 502 !tls13_derive_early_secrets(hs) || 503 !tls13_set_traffic_key(ssl, evp_aead_seal, hs->early_traffic_secret, 504 hs->hash_len)) { 505 return ssl_hs_error; 506 } 507 508 // Stash the early data session, so connection properties may be queried out 509 // of it. 510 hs->in_early_data = true; 511 SSL_SESSION_up_ref(ssl->session); 512 hs->early_session.reset(ssl->session); 513 hs->can_early_write = true; 514 515 hs->state = state_read_server_hello; 516 return ssl_hs_early_return; 517 } 518 519 static enum ssl_hs_wait_t do_read_hello_verify_request(SSL_HANDSHAKE *hs) { 520 SSL *const ssl = hs->ssl; 521 522 assert(SSL_is_dtls(ssl)); 523 524 SSLMessage msg; 525 if (!ssl->method->get_message(ssl, &msg)) { 526 return ssl_hs_read_message; 527 } 528 529 if (msg.type != DTLS1_MT_HELLO_VERIFY_REQUEST) { 530 hs->state = state_read_server_hello; 531 return ssl_hs_ok; 532 } 533 534 CBS hello_verify_request = msg.body, cookie; 535 uint16_t server_version; 536 if (!CBS_get_u16(&hello_verify_request, &server_version) || 537 !CBS_get_u8_length_prefixed(&hello_verify_request, &cookie) || 538 CBS_len(&cookie) > sizeof(ssl->d1->cookie) || 539 CBS_len(&hello_verify_request) != 0) { 540 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 541 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 542 return ssl_hs_error; 543 } 544 545 OPENSSL_memcpy(ssl->d1->cookie, CBS_data(&cookie), CBS_len(&cookie)); 546 ssl->d1->cookie_len = CBS_len(&cookie); 547 548 ssl->method->next_message(ssl); 549 550 // DTLS resets the handshake buffer after HelloVerifyRequest. 551 if (!hs->transcript.Init()) { 552 return ssl_hs_error; 553 } 554 555 if (!ssl_write_client_hello(hs)) { 556 return ssl_hs_error; 557 } 558 559 hs->state = state_read_server_hello; 560 return ssl_hs_flush; 561 } 562 563 static enum ssl_hs_wait_t do_read_server_hello(SSL_HANDSHAKE *hs) { 564 SSL *const ssl = hs->ssl; 565 SSLMessage msg; 566 if (!ssl->method->get_message(ssl, &msg)) { 567 return ssl_hs_read_server_hello; 568 } 569 570 uint16_t server_version; 571 if (!parse_server_version(hs, &server_version, msg)) { 572 return ssl_hs_error; 573 } 574 575 if (!ssl_supports_version(hs, server_version)) { 576 OPENSSL_PUT_ERROR(SSL, SSL_R_UNSUPPORTED_PROTOCOL); 577 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_PROTOCOL_VERSION); 578 return ssl_hs_error; 579 } 580 581 assert(ssl->s3->have_version == ssl->s3->initial_handshake_complete); 582 if (!ssl->s3->have_version) { 583 ssl->version = server_version; 584 // At this point, the connection's version is known and ssl->version is 585 // fixed. Begin enforcing the record-layer version. 586 ssl->s3->have_version = true; 587 ssl->s3->aead_write_ctx->SetVersionIfNullCipher(ssl->version); 588 } else if (server_version != ssl->version) { 589 OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_SSL_VERSION); 590 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_PROTOCOL_VERSION); 591 return ssl_hs_error; 592 } 593 594 if (ssl_protocol_version(ssl) >= TLS1_3_VERSION) { 595 hs->state = state_tls13; 596 return ssl_hs_ok; 597 } 598 599 // Clear some TLS 1.3 state that no longer needs to be retained. 600 hs->key_share.reset(); 601 hs->key_share_bytes.Reset(); 602 603 // A TLS 1.2 server would not know to skip the early data we offered. Report 604 // an error code sooner. The caller may use this error code to implement the 605 // fallback described in draft-ietf-tls-tls13-18 appendix C.3. 606 if (hs->early_data_offered) { 607 OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_VERSION_ON_EARLY_DATA); 608 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_PROTOCOL_VERSION); 609 return ssl_hs_error; 610 } 611 612 if (!ssl_check_message_type(ssl, msg, SSL3_MT_SERVER_HELLO)) { 613 return ssl_hs_error; 614 } 615 616 CBS server_hello = msg.body, server_random, session_id; 617 uint16_t cipher_suite; 618 uint8_t compression_method; 619 if (!CBS_skip(&server_hello, 2 /* version */) || 620 !CBS_get_bytes(&server_hello, &server_random, SSL3_RANDOM_SIZE) || 621 !CBS_get_u8_length_prefixed(&server_hello, &session_id) || 622 CBS_len(&session_id) > SSL3_SESSION_ID_SIZE || 623 !CBS_get_u16(&server_hello, &cipher_suite) || 624 !CBS_get_u8(&server_hello, &compression_method)) { 625 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 626 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 627 return ssl_hs_error; 628 } 629 630 // Copy over the server random. 631 OPENSSL_memcpy(ssl->s3->server_random, CBS_data(&server_random), 632 SSL3_RANDOM_SIZE); 633 634 // Measure, but do not enforce, the TLS 1.3 anti-downgrade feature, with a 635 // different value. 636 // 637 // For draft TLS 1.3 versions, it is not safe to deploy this feature. However, 638 // some TLS terminators are non-compliant and copy the origin server's value, 639 // so we wish to measure eventual compatibility impact. 640 if (!ssl->s3->initial_handshake_complete && 641 hs->max_version >= TLS1_3_VERSION && 642 OPENSSL_memcmp(ssl->s3->server_random + SSL3_RANDOM_SIZE - 643 sizeof(kDraftDowngradeRandom), 644 kDraftDowngradeRandom, 645 sizeof(kDraftDowngradeRandom)) == 0) { 646 ssl->s3->draft_downgrade = true; 647 } 648 649 if (!ssl->s3->initial_handshake_complete && ssl->session != NULL && 650 ssl->session->session_id_length != 0 && 651 CBS_mem_equal(&session_id, ssl->session->session_id, 652 ssl->session->session_id_length)) { 653 ssl->s3->session_reused = true; 654 } else { 655 // The server may also have echoed back the TLS 1.3 compatibility mode 656 // session ID. As we know this is not a session the server knows about, any 657 // server resuming it is in error. Reject the first connection 658 // deterministicly, rather than installing an invalid session into the 659 // session cache. https://crbug.com/796910 660 if (hs->session_id_len != 0 && 661 CBS_mem_equal(&session_id, hs->session_id, hs->session_id_len)) { 662 OPENSSL_PUT_ERROR(SSL, SSL_R_SERVER_ECHOED_INVALID_SESSION_ID); 663 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 664 return ssl_hs_error; 665 } 666 667 // The session wasn't resumed. Create a fresh SSL_SESSION to 668 // fill out. 669 ssl_set_session(ssl, NULL); 670 if (!ssl_get_new_session(hs, 0 /* client */)) { 671 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); 672 return ssl_hs_error; 673 } 674 // Note: session_id could be empty. 675 hs->new_session->session_id_length = CBS_len(&session_id); 676 OPENSSL_memcpy(hs->new_session->session_id, CBS_data(&session_id), 677 CBS_len(&session_id)); 678 } 679 680 const SSL_CIPHER *cipher = SSL_get_cipher_by_value(cipher_suite); 681 if (cipher == NULL) { 682 // unknown cipher 683 OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_CIPHER_RETURNED); 684 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 685 return ssl_hs_error; 686 } 687 688 // The cipher must be allowed in the selected version and enabled. 689 uint32_t mask_a, mask_k; 690 ssl_get_client_disabled(ssl, &mask_a, &mask_k); 691 if ((cipher->algorithm_mkey & mask_k) || (cipher->algorithm_auth & mask_a) || 692 SSL_CIPHER_get_min_version(cipher) > ssl_protocol_version(ssl) || 693 SSL_CIPHER_get_max_version(cipher) < ssl_protocol_version(ssl) || 694 !sk_SSL_CIPHER_find(SSL_get_ciphers(ssl), NULL, cipher)) { 695 OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CIPHER_RETURNED); 696 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 697 return ssl_hs_error; 698 } 699 700 if (ssl->session != NULL) { 701 if (ssl->session->ssl_version != ssl->version) { 702 OPENSSL_PUT_ERROR(SSL, SSL_R_OLD_SESSION_VERSION_NOT_RETURNED); 703 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 704 return ssl_hs_error; 705 } 706 if (ssl->session->cipher != cipher) { 707 OPENSSL_PUT_ERROR(SSL, SSL_R_OLD_SESSION_CIPHER_NOT_RETURNED); 708 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 709 return ssl_hs_error; 710 } 711 if (!ssl_session_is_context_valid(ssl, ssl->session)) { 712 // This is actually a client application bug. 713 OPENSSL_PUT_ERROR(SSL, 714 SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT); 715 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 716 return ssl_hs_error; 717 } 718 } else { 719 hs->new_session->cipher = cipher; 720 } 721 hs->new_cipher = cipher; 722 723 // Now that the cipher is known, initialize the handshake hash and hash the 724 // ServerHello. 725 if (!hs->transcript.InitHash(ssl_protocol_version(ssl), hs->new_cipher) || 726 !ssl_hash_message(hs, msg)) { 727 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); 728 return ssl_hs_error; 729 } 730 731 // If doing a full handshake, the server may request a client certificate 732 // which requires hashing the handshake transcript. Otherwise, the handshake 733 // buffer may be released. 734 if (ssl->session != NULL || 735 !ssl_cipher_uses_certificate_auth(hs->new_cipher)) { 736 hs->transcript.FreeBuffer(); 737 } 738 739 // Only the NULL compression algorithm is supported. 740 if (compression_method != 0) { 741 OPENSSL_PUT_ERROR(SSL, SSL_R_UNSUPPORTED_COMPRESSION_ALGORITHM); 742 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 743 return ssl_hs_error; 744 } 745 746 // TLS extensions 747 if (!ssl_parse_serverhello_tlsext(hs, &server_hello)) { 748 OPENSSL_PUT_ERROR(SSL, SSL_R_PARSE_TLSEXT); 749 return ssl_hs_error; 750 } 751 752 // There should be nothing left over in the record. 753 if (CBS_len(&server_hello) != 0) { 754 // wrong packet length 755 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 756 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 757 return ssl_hs_error; 758 } 759 760 if (ssl->session != NULL && 761 hs->extended_master_secret != ssl->session->extended_master_secret) { 762 if (ssl->session->extended_master_secret) { 763 OPENSSL_PUT_ERROR(SSL, SSL_R_RESUMED_EMS_SESSION_WITHOUT_EMS_EXTENSION); 764 } else { 765 OPENSSL_PUT_ERROR(SSL, SSL_R_RESUMED_NON_EMS_SESSION_WITH_EMS_EXTENSION); 766 } 767 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); 768 return ssl_hs_error; 769 } 770 771 if (ssl->token_binding_negotiated && 772 (!hs->extended_master_secret || !ssl->s3->send_connection_binding)) { 773 OPENSSL_PUT_ERROR(SSL, SSL_R_NEGOTIATED_TB_WITHOUT_EMS_OR_RI); 774 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNSUPPORTED_EXTENSION); 775 return ssl_hs_error; 776 } 777 778 ssl->method->next_message(ssl); 779 780 if (ssl->session != NULL) { 781 hs->state = state_read_session_ticket; 782 return ssl_hs_ok; 783 } 784 785 hs->state = state_read_server_certificate; 786 return ssl_hs_ok; 787 } 788 789 static enum ssl_hs_wait_t do_tls13(SSL_HANDSHAKE *hs) { 790 enum ssl_hs_wait_t wait = tls13_client_handshake(hs); 791 if (wait == ssl_hs_ok) { 792 hs->state = state_finish_client_handshake; 793 return ssl_hs_ok; 794 } 795 796 return wait; 797 } 798 799 static enum ssl_hs_wait_t do_read_server_certificate(SSL_HANDSHAKE *hs) { 800 SSL *const ssl = hs->ssl; 801 802 if (!ssl_cipher_uses_certificate_auth(hs->new_cipher)) { 803 hs->state = state_read_certificate_status; 804 return ssl_hs_ok; 805 } 806 807 SSLMessage msg; 808 if (!ssl->method->get_message(ssl, &msg)) { 809 return ssl_hs_read_message; 810 } 811 812 if (!ssl_check_message_type(ssl, msg, SSL3_MT_CERTIFICATE) || 813 !ssl_hash_message(hs, msg)) { 814 return ssl_hs_error; 815 } 816 817 CBS body = msg.body; 818 uint8_t alert = SSL_AD_DECODE_ERROR; 819 UniquePtr<STACK_OF(CRYPTO_BUFFER)> chain; 820 if (!ssl_parse_cert_chain(&alert, &chain, &hs->peer_pubkey, NULL, &body, 821 ssl->ctx->pool)) { 822 ssl_send_alert(ssl, SSL3_AL_FATAL, alert); 823 return ssl_hs_error; 824 } 825 sk_CRYPTO_BUFFER_pop_free(hs->new_session->certs, CRYPTO_BUFFER_free); 826 hs->new_session->certs = chain.release(); 827 828 if (sk_CRYPTO_BUFFER_num(hs->new_session->certs) == 0 || 829 CBS_len(&body) != 0 || 830 !ssl->ctx->x509_method->session_cache_objects(hs->new_session.get())) { 831 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 832 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 833 return ssl_hs_error; 834 } 835 836 if (!ssl_check_leaf_certificate( 837 hs, hs->peer_pubkey.get(), 838 sk_CRYPTO_BUFFER_value(hs->new_session->certs, 0))) { 839 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 840 return ssl_hs_error; 841 } 842 843 ssl->method->next_message(ssl); 844 845 hs->state = state_read_certificate_status; 846 return ssl_hs_ok; 847 } 848 849 static enum ssl_hs_wait_t do_read_certificate_status(SSL_HANDSHAKE *hs) { 850 SSL *const ssl = hs->ssl; 851 852 if (!hs->certificate_status_expected) { 853 hs->state = state_verify_server_certificate; 854 return ssl_hs_ok; 855 } 856 857 SSLMessage msg; 858 if (!ssl->method->get_message(ssl, &msg)) { 859 return ssl_hs_read_message; 860 } 861 862 if (msg.type != SSL3_MT_CERTIFICATE_STATUS) { 863 // A server may send status_request in ServerHello and then change its mind 864 // about sending CertificateStatus. 865 hs->state = state_verify_server_certificate; 866 return ssl_hs_ok; 867 } 868 869 if (!ssl_hash_message(hs, msg)) { 870 return ssl_hs_error; 871 } 872 873 CBS certificate_status = msg.body, ocsp_response; 874 uint8_t status_type; 875 if (!CBS_get_u8(&certificate_status, &status_type) || 876 status_type != TLSEXT_STATUSTYPE_ocsp || 877 !CBS_get_u24_length_prefixed(&certificate_status, &ocsp_response) || 878 CBS_len(&ocsp_response) == 0 || 879 CBS_len(&certificate_status) != 0) { 880 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 881 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 882 return ssl_hs_error; 883 } 884 885 CRYPTO_BUFFER_free(hs->new_session->ocsp_response); 886 hs->new_session->ocsp_response = 887 CRYPTO_BUFFER_new_from_CBS(&ocsp_response, ssl->ctx->pool); 888 if (hs->new_session->ocsp_response == nullptr) { 889 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); 890 return ssl_hs_error; 891 } 892 893 ssl->method->next_message(ssl); 894 895 hs->state = state_verify_server_certificate; 896 return ssl_hs_ok; 897 } 898 899 static enum ssl_hs_wait_t do_verify_server_certificate(SSL_HANDSHAKE *hs) { 900 if (!ssl_cipher_uses_certificate_auth(hs->new_cipher)) { 901 hs->state = state_read_server_key_exchange; 902 return ssl_hs_ok; 903 } 904 905 switch (ssl_verify_peer_cert(hs)) { 906 case ssl_verify_ok: 907 break; 908 case ssl_verify_invalid: 909 return ssl_hs_error; 910 case ssl_verify_retry: 911 hs->state = state_verify_server_certificate; 912 return ssl_hs_certificate_verify; 913 } 914 915 hs->state = state_read_server_key_exchange; 916 return ssl_hs_ok; 917 } 918 919 static enum ssl_hs_wait_t do_read_server_key_exchange(SSL_HANDSHAKE *hs) { 920 SSL *const ssl = hs->ssl; 921 SSLMessage msg; 922 if (!ssl->method->get_message(ssl, &msg)) { 923 return ssl_hs_read_message; 924 } 925 926 if (msg.type != SSL3_MT_SERVER_KEY_EXCHANGE) { 927 // Some ciphers (pure PSK) have an optional ServerKeyExchange message. 928 if (ssl_cipher_requires_server_key_exchange(hs->new_cipher)) { 929 OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE); 930 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE); 931 return ssl_hs_error; 932 } 933 934 hs->state = state_read_certificate_request; 935 return ssl_hs_ok; 936 } 937 938 if (!ssl_hash_message(hs, msg)) { 939 return ssl_hs_error; 940 } 941 942 uint32_t alg_k = hs->new_cipher->algorithm_mkey; 943 uint32_t alg_a = hs->new_cipher->algorithm_auth; 944 CBS server_key_exchange = msg.body; 945 if (alg_a & SSL_aPSK) { 946 CBS psk_identity_hint; 947 948 // Each of the PSK key exchanges begins with a psk_identity_hint. 949 if (!CBS_get_u16_length_prefixed(&server_key_exchange, 950 &psk_identity_hint)) { 951 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 952 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 953 return ssl_hs_error; 954 } 955 956 // Store the PSK identity hint for the ClientKeyExchange. Assume that the 957 // maximum length of a PSK identity hint can be as long as the maximum 958 // length of a PSK identity. Also do not allow NULL characters; identities 959 // are saved as C strings. 960 // 961 // TODO(davidben): Should invalid hints be ignored? It's a hint rather than 962 // a specific identity. 963 if (CBS_len(&psk_identity_hint) > PSK_MAX_IDENTITY_LEN || 964 CBS_contains_zero_byte(&psk_identity_hint)) { 965 OPENSSL_PUT_ERROR(SSL, SSL_R_DATA_LENGTH_TOO_LONG); 966 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); 967 return ssl_hs_error; 968 } 969 970 // Save non-empty identity hints as a C string. Empty identity hints we 971 // treat as missing. Plain PSK makes it possible to send either no hint 972 // (omit ServerKeyExchange) or an empty hint, while ECDHE_PSK can only spell 973 // empty hint. Having different capabilities is odd, so we interpret empty 974 // and missing as identical. 975 char *raw = nullptr; 976 if (CBS_len(&psk_identity_hint) != 0 && 977 !CBS_strdup(&psk_identity_hint, &raw)) { 978 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 979 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); 980 return ssl_hs_error; 981 } 982 hs->peer_psk_identity_hint.reset(raw); 983 } 984 985 if (alg_k & SSL_kECDHE) { 986 // Parse the server parameters. 987 uint8_t group_type; 988 uint16_t group_id; 989 CBS point; 990 if (!CBS_get_u8(&server_key_exchange, &group_type) || 991 group_type != NAMED_CURVE_TYPE || 992 !CBS_get_u16(&server_key_exchange, &group_id) || 993 !CBS_get_u8_length_prefixed(&server_key_exchange, &point)) { 994 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 995 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 996 return ssl_hs_error; 997 } 998 hs->new_session->group_id = group_id; 999 1000 // Ensure the group is consistent with preferences. 1001 if (!tls1_check_group_id(ssl, group_id)) { 1002 OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CURVE); 1003 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 1004 return ssl_hs_error; 1005 } 1006 1007 // Initialize ECDH and save the peer public key for later. 1008 hs->key_share = SSLKeyShare::Create(group_id); 1009 if (!hs->key_share || 1010 !hs->peer_key.CopyFrom(point)) { 1011 return ssl_hs_error; 1012 } 1013 } else if (!(alg_k & SSL_kPSK)) { 1014 OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE); 1015 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE); 1016 return ssl_hs_error; 1017 } 1018 1019 // At this point, |server_key_exchange| contains the signature, if any, while 1020 // |msg.body| contains the entire message. From that, derive a CBS containing 1021 // just the parameter. 1022 CBS parameter; 1023 CBS_init(¶meter, CBS_data(&msg.body), 1024 CBS_len(&msg.body) - CBS_len(&server_key_exchange)); 1025 1026 // ServerKeyExchange should be signed by the server's public key. 1027 if (ssl_cipher_uses_certificate_auth(hs->new_cipher)) { 1028 uint16_t signature_algorithm = 0; 1029 if (ssl_protocol_version(ssl) >= TLS1_2_VERSION) { 1030 if (!CBS_get_u16(&server_key_exchange, &signature_algorithm)) { 1031 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1032 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1033 return ssl_hs_error; 1034 } 1035 uint8_t alert = SSL_AD_DECODE_ERROR; 1036 if (!tls12_check_peer_sigalg(ssl, &alert, signature_algorithm)) { 1037 ssl_send_alert(ssl, SSL3_AL_FATAL, alert); 1038 return ssl_hs_error; 1039 } 1040 hs->new_session->peer_signature_algorithm = signature_algorithm; 1041 } else if (!tls1_get_legacy_signature_algorithm(&signature_algorithm, 1042 hs->peer_pubkey.get())) { 1043 OPENSSL_PUT_ERROR(SSL, SSL_R_PEER_ERROR_UNSUPPORTED_CERTIFICATE_TYPE); 1044 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNSUPPORTED_CERTIFICATE); 1045 return ssl_hs_error; 1046 } 1047 1048 // The last field in |server_key_exchange| is the signature. 1049 CBS signature; 1050 if (!CBS_get_u16_length_prefixed(&server_key_exchange, &signature) || 1051 CBS_len(&server_key_exchange) != 0) { 1052 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1053 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1054 return ssl_hs_error; 1055 } 1056 1057 ScopedCBB transcript; 1058 Array<uint8_t> transcript_data; 1059 if (!CBB_init(transcript.get(), 1060 2 * SSL3_RANDOM_SIZE + CBS_len(¶meter)) || 1061 !CBB_add_bytes(transcript.get(), ssl->s3->client_random, 1062 SSL3_RANDOM_SIZE) || 1063 !CBB_add_bytes(transcript.get(), ssl->s3->server_random, 1064 SSL3_RANDOM_SIZE) || 1065 !CBB_add_bytes(transcript.get(), CBS_data(¶meter), 1066 CBS_len(¶meter)) || 1067 !CBBFinishArray(transcript.get(), &transcript_data)) { 1068 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1069 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); 1070 return ssl_hs_error; 1071 } 1072 1073 bool sig_ok = ssl_public_key_verify(ssl, signature, signature_algorithm, 1074 hs->peer_pubkey.get(), transcript_data); 1075 #if defined(BORINGSSL_UNSAFE_FUZZER_MODE) 1076 sig_ok = true; 1077 ERR_clear_error(); 1078 #endif 1079 if (!sig_ok) { 1080 // bad signature 1081 OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_SIGNATURE); 1082 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECRYPT_ERROR); 1083 return ssl_hs_error; 1084 } 1085 } else { 1086 // PSK ciphers are the only supported certificate-less ciphers. 1087 assert(alg_a == SSL_aPSK); 1088 1089 if (CBS_len(&server_key_exchange) > 0) { 1090 OPENSSL_PUT_ERROR(SSL, SSL_R_EXTRA_DATA_IN_MESSAGE); 1091 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1092 return ssl_hs_error; 1093 } 1094 } 1095 1096 ssl->method->next_message(ssl); 1097 hs->state = state_read_certificate_request; 1098 return ssl_hs_ok; 1099 } 1100 1101 static enum ssl_hs_wait_t do_read_certificate_request(SSL_HANDSHAKE *hs) { 1102 SSL *const ssl = hs->ssl; 1103 1104 if (!ssl_cipher_uses_certificate_auth(hs->new_cipher)) { 1105 hs->state = state_read_server_hello_done; 1106 return ssl_hs_ok; 1107 } 1108 1109 SSLMessage msg; 1110 if (!ssl->method->get_message(ssl, &msg)) { 1111 return ssl_hs_read_message; 1112 } 1113 1114 if (msg.type == SSL3_MT_SERVER_HELLO_DONE) { 1115 // If we get here we don't need the handshake buffer as we won't be doing 1116 // client auth. 1117 hs->transcript.FreeBuffer(); 1118 hs->state = state_read_server_hello_done; 1119 return ssl_hs_ok; 1120 } 1121 1122 if (!ssl_check_message_type(ssl, msg, SSL3_MT_CERTIFICATE_REQUEST) || 1123 !ssl_hash_message(hs, msg)) { 1124 return ssl_hs_error; 1125 } 1126 1127 // Get the certificate types. 1128 CBS body = msg.body, certificate_types; 1129 if (!CBS_get_u8_length_prefixed(&body, &certificate_types)) { 1130 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1131 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1132 return ssl_hs_error; 1133 } 1134 1135 if (!hs->certificate_types.CopyFrom(certificate_types)) { 1136 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); 1137 return ssl_hs_error; 1138 } 1139 1140 if (ssl_protocol_version(ssl) >= TLS1_2_VERSION) { 1141 CBS supported_signature_algorithms; 1142 if (!CBS_get_u16_length_prefixed(&body, &supported_signature_algorithms) || 1143 !tls1_parse_peer_sigalgs(hs, &supported_signature_algorithms)) { 1144 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1145 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1146 return ssl_hs_error; 1147 } 1148 } 1149 1150 uint8_t alert = SSL_AD_DECODE_ERROR; 1151 UniquePtr<STACK_OF(CRYPTO_BUFFER)> ca_names = 1152 ssl_parse_client_CA_list(ssl, &alert, &body); 1153 if (!ca_names) { 1154 ssl_send_alert(ssl, SSL3_AL_FATAL, alert); 1155 return ssl_hs_error; 1156 } 1157 1158 if (CBS_len(&body) != 0) { 1159 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1160 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1161 return ssl_hs_error; 1162 } 1163 1164 hs->cert_request = true; 1165 hs->ca_names = std::move(ca_names); 1166 ssl->ctx->x509_method->hs_flush_cached_ca_names(hs); 1167 1168 ssl->method->next_message(ssl); 1169 hs->state = state_read_server_hello_done; 1170 return ssl_hs_ok; 1171 } 1172 1173 static enum ssl_hs_wait_t do_read_server_hello_done(SSL_HANDSHAKE *hs) { 1174 SSL *const ssl = hs->ssl; 1175 SSLMessage msg; 1176 if (!ssl->method->get_message(ssl, &msg)) { 1177 return ssl_hs_read_message; 1178 } 1179 1180 if (!ssl_check_message_type(ssl, msg, SSL3_MT_SERVER_HELLO_DONE) || 1181 !ssl_hash_message(hs, msg)) { 1182 return ssl_hs_error; 1183 } 1184 1185 // ServerHelloDone is empty. 1186 if (CBS_len(&msg.body) != 0) { 1187 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1188 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1189 return ssl_hs_error; 1190 } 1191 1192 ssl->method->next_message(ssl); 1193 hs->state = state_send_client_certificate; 1194 return ssl_hs_ok; 1195 } 1196 1197 static enum ssl_hs_wait_t do_send_client_certificate(SSL_HANDSHAKE *hs) { 1198 SSL *const ssl = hs->ssl; 1199 1200 // The peer didn't request a certificate. 1201 if (!hs->cert_request) { 1202 hs->state = state_send_client_key_exchange; 1203 return ssl_hs_ok; 1204 } 1205 1206 // Call cert_cb to update the certificate. 1207 if (ssl->cert->cert_cb != NULL) { 1208 int rv = ssl->cert->cert_cb(ssl, ssl->cert->cert_cb_arg); 1209 if (rv == 0) { 1210 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); 1211 OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_CB_ERROR); 1212 return ssl_hs_error; 1213 } 1214 if (rv < 0) { 1215 hs->state = state_send_client_certificate; 1216 return ssl_hs_x509_lookup; 1217 } 1218 } 1219 1220 if (!ssl_has_certificate(ssl)) { 1221 // Without a client certificate, the handshake buffer may be released. 1222 hs->transcript.FreeBuffer(); 1223 1224 // In SSL 3.0, the Certificate message is replaced with a warning alert. 1225 if (ssl->version == SSL3_VERSION) { 1226 if (!ssl->method->add_alert(ssl, SSL3_AL_WARNING, 1227 SSL_AD_NO_CERTIFICATE)) { 1228 return ssl_hs_error; 1229 } 1230 hs->state = state_send_client_key_exchange; 1231 return ssl_hs_ok; 1232 } 1233 } 1234 1235 if (!ssl_on_certificate_selected(hs) || 1236 !ssl_output_cert_chain(ssl)) { 1237 return ssl_hs_error; 1238 } 1239 1240 1241 hs->state = state_send_client_key_exchange; 1242 return ssl_hs_ok; 1243 } 1244 1245 static_assert(sizeof(size_t) >= sizeof(unsigned), 1246 "size_t is smaller than unsigned"); 1247 1248 static enum ssl_hs_wait_t do_send_client_key_exchange(SSL_HANDSHAKE *hs) { 1249 SSL *const ssl = hs->ssl; 1250 ScopedCBB cbb; 1251 CBB body; 1252 if (!ssl->method->init_message(ssl, cbb.get(), &body, 1253 SSL3_MT_CLIENT_KEY_EXCHANGE)) { 1254 return ssl_hs_error; 1255 } 1256 1257 Array<uint8_t> pms; 1258 uint32_t alg_k = hs->new_cipher->algorithm_mkey; 1259 uint32_t alg_a = hs->new_cipher->algorithm_auth; 1260 1261 // If using a PSK key exchange, prepare the pre-shared key. 1262 unsigned psk_len = 0; 1263 uint8_t psk[PSK_MAX_PSK_LEN]; 1264 if (alg_a & SSL_aPSK) { 1265 if (ssl->psk_client_callback == NULL) { 1266 OPENSSL_PUT_ERROR(SSL, SSL_R_PSK_NO_CLIENT_CB); 1267 return ssl_hs_error; 1268 } 1269 1270 char identity[PSK_MAX_IDENTITY_LEN + 1]; 1271 OPENSSL_memset(identity, 0, sizeof(identity)); 1272 psk_len = 1273 ssl->psk_client_callback(ssl, hs->peer_psk_identity_hint.get(), 1274 identity, sizeof(identity), psk, sizeof(psk)); 1275 if (psk_len == 0) { 1276 OPENSSL_PUT_ERROR(SSL, SSL_R_PSK_IDENTITY_NOT_FOUND); 1277 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); 1278 return ssl_hs_error; 1279 } 1280 assert(psk_len <= PSK_MAX_PSK_LEN); 1281 1282 OPENSSL_free(hs->new_session->psk_identity); 1283 hs->new_session->psk_identity = BUF_strdup(identity); 1284 if (hs->new_session->psk_identity == NULL) { 1285 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1286 return ssl_hs_error; 1287 } 1288 1289 // Write out psk_identity. 1290 CBB child; 1291 if (!CBB_add_u16_length_prefixed(&body, &child) || 1292 !CBB_add_bytes(&child, (const uint8_t *)identity, 1293 OPENSSL_strnlen(identity, sizeof(identity))) || 1294 !CBB_flush(&body)) { 1295 return ssl_hs_error; 1296 } 1297 } 1298 1299 // Depending on the key exchange method, compute |pms|. 1300 if (alg_k & SSL_kRSA) { 1301 if (!pms.Init(SSL_MAX_MASTER_KEY_LENGTH)) { 1302 return ssl_hs_error; 1303 } 1304 1305 RSA *rsa = EVP_PKEY_get0_RSA(hs->peer_pubkey.get()); 1306 if (rsa == NULL) { 1307 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1308 return ssl_hs_error; 1309 } 1310 1311 pms[0] = hs->client_version >> 8; 1312 pms[1] = hs->client_version & 0xff; 1313 if (!RAND_bytes(&pms[2], SSL_MAX_MASTER_KEY_LENGTH - 2)) { 1314 return ssl_hs_error; 1315 } 1316 1317 CBB child, *enc_pms = &body; 1318 size_t enc_pms_len; 1319 // In TLS, there is a length prefix. 1320 if (ssl->version > SSL3_VERSION) { 1321 if (!CBB_add_u16_length_prefixed(&body, &child)) { 1322 return ssl_hs_error; 1323 } 1324 enc_pms = &child; 1325 } 1326 1327 uint8_t *ptr; 1328 if (!CBB_reserve(enc_pms, &ptr, RSA_size(rsa)) || 1329 !RSA_encrypt(rsa, &enc_pms_len, ptr, RSA_size(rsa), pms.data(), 1330 pms.size(), RSA_PKCS1_PADDING) || 1331 !CBB_did_write(enc_pms, enc_pms_len) || 1332 !CBB_flush(&body)) { 1333 return ssl_hs_error; 1334 } 1335 } else if (alg_k & SSL_kECDHE) { 1336 // Generate a keypair and serialize the public half. 1337 CBB child; 1338 if (!CBB_add_u8_length_prefixed(&body, &child)) { 1339 return ssl_hs_error; 1340 } 1341 1342 // Compute the premaster. 1343 uint8_t alert = SSL_AD_DECODE_ERROR; 1344 if (!hs->key_share->Accept(&child, &pms, &alert, hs->peer_key)) { 1345 ssl_send_alert(ssl, SSL3_AL_FATAL, alert); 1346 return ssl_hs_error; 1347 } 1348 if (!CBB_flush(&body)) { 1349 return ssl_hs_error; 1350 } 1351 1352 // The key exchange state may now be discarded. 1353 hs->key_share.reset(); 1354 hs->peer_key.Reset(); 1355 } else if (alg_k & SSL_kPSK) { 1356 // For plain PSK, other_secret is a block of 0s with the same length as 1357 // the pre-shared key. 1358 if (!pms.Init(psk_len)) { 1359 return ssl_hs_error; 1360 } 1361 OPENSSL_memset(pms.data(), 0, pms.size()); 1362 } else { 1363 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); 1364 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1365 return ssl_hs_error; 1366 } 1367 1368 // For a PSK cipher suite, other_secret is combined with the pre-shared 1369 // key. 1370 if (alg_a & SSL_aPSK) { 1371 ScopedCBB pms_cbb; 1372 CBB child; 1373 if (!CBB_init(pms_cbb.get(), 2 + psk_len + 2 + pms.size()) || 1374 !CBB_add_u16_length_prefixed(pms_cbb.get(), &child) || 1375 !CBB_add_bytes(&child, pms.data(), pms.size()) || 1376 !CBB_add_u16_length_prefixed(pms_cbb.get(), &child) || 1377 !CBB_add_bytes(&child, psk, psk_len) || 1378 !CBBFinishArray(pms_cbb.get(), &pms)) { 1379 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1380 return ssl_hs_error; 1381 } 1382 } 1383 1384 // The message must be added to the finished hash before calculating the 1385 // master secret. 1386 if (!ssl_add_message_cbb(ssl, cbb.get())) { 1387 return ssl_hs_error; 1388 } 1389 1390 hs->new_session->master_key_length = 1391 tls1_generate_master_secret(hs, hs->new_session->master_key, pms); 1392 if (hs->new_session->master_key_length == 0) { 1393 return ssl_hs_error; 1394 } 1395 hs->new_session->extended_master_secret = hs->extended_master_secret; 1396 1397 hs->state = state_send_client_certificate_verify; 1398 return ssl_hs_ok; 1399 } 1400 1401 static enum ssl_hs_wait_t do_send_client_certificate_verify(SSL_HANDSHAKE *hs) { 1402 SSL *const ssl = hs->ssl; 1403 1404 if (!hs->cert_request || !ssl_has_certificate(ssl)) { 1405 hs->state = state_send_client_finished; 1406 return ssl_hs_ok; 1407 } 1408 1409 assert(ssl_has_private_key(ssl)); 1410 ScopedCBB cbb; 1411 CBB body, child; 1412 if (!ssl->method->init_message(ssl, cbb.get(), &body, 1413 SSL3_MT_CERTIFICATE_VERIFY)) { 1414 return ssl_hs_error; 1415 } 1416 1417 uint16_t signature_algorithm; 1418 if (!tls1_choose_signature_algorithm(hs, &signature_algorithm)) { 1419 return ssl_hs_error; 1420 } 1421 if (ssl_protocol_version(ssl) >= TLS1_2_VERSION) { 1422 // Write out the digest type in TLS 1.2. 1423 if (!CBB_add_u16(&body, signature_algorithm)) { 1424 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1425 return ssl_hs_error; 1426 } 1427 } 1428 1429 // Set aside space for the signature. 1430 const size_t max_sig_len = EVP_PKEY_size(hs->local_pubkey.get()); 1431 uint8_t *ptr; 1432 if (!CBB_add_u16_length_prefixed(&body, &child) || 1433 !CBB_reserve(&child, &ptr, max_sig_len)) { 1434 return ssl_hs_error; 1435 } 1436 1437 size_t sig_len = max_sig_len; 1438 // The SSL3 construction for CertificateVerify does not decompose into a 1439 // single final digest and signature, and must be special-cased. 1440 if (ssl_protocol_version(ssl) == SSL3_VERSION) { 1441 if (ssl->cert->key_method != NULL) { 1442 OPENSSL_PUT_ERROR(SSL, SSL_R_UNSUPPORTED_PROTOCOL_FOR_CUSTOM_KEY); 1443 return ssl_hs_error; 1444 } 1445 1446 uint8_t digest[EVP_MAX_MD_SIZE]; 1447 size_t digest_len; 1448 if (!hs->transcript.GetSSL3CertVerifyHash( 1449 digest, &digest_len, hs->new_session.get(), signature_algorithm)) { 1450 return ssl_hs_error; 1451 } 1452 1453 UniquePtr<EVP_PKEY_CTX> pctx(EVP_PKEY_CTX_new(ssl->cert->privatekey, NULL)); 1454 if (!pctx || 1455 !EVP_PKEY_sign_init(pctx.get()) || 1456 !EVP_PKEY_sign(pctx.get(), ptr, &sig_len, digest, digest_len)) { 1457 return ssl_hs_error; 1458 } 1459 } else { 1460 switch (ssl_private_key_sign(hs, ptr, &sig_len, max_sig_len, 1461 signature_algorithm, 1462 hs->transcript.buffer())) { 1463 case ssl_private_key_success: 1464 break; 1465 case ssl_private_key_failure: 1466 return ssl_hs_error; 1467 case ssl_private_key_retry: 1468 hs->state = state_send_client_certificate_verify; 1469 return ssl_hs_private_key_operation; 1470 } 1471 } 1472 1473 if (!CBB_did_write(&child, sig_len) || 1474 !ssl_add_message_cbb(ssl, cbb.get())) { 1475 return ssl_hs_error; 1476 } 1477 1478 // The handshake buffer is no longer necessary. 1479 hs->transcript.FreeBuffer(); 1480 1481 hs->state = state_send_client_finished; 1482 return ssl_hs_ok; 1483 } 1484 1485 static enum ssl_hs_wait_t do_send_client_finished(SSL_HANDSHAKE *hs) { 1486 SSL *const ssl = hs->ssl; 1487 // Resolve Channel ID first, before any non-idempotent operations. 1488 if (ssl->s3->tlsext_channel_id_valid) { 1489 if (!ssl_do_channel_id_callback(ssl)) { 1490 return ssl_hs_error; 1491 } 1492 1493 if (ssl->tlsext_channel_id_private == NULL) { 1494 hs->state = state_send_client_finished; 1495 return ssl_hs_channel_id_lookup; 1496 } 1497 } 1498 1499 if (!ssl->method->add_change_cipher_spec(ssl) || 1500 !tls1_change_cipher_state(hs, evp_aead_seal)) { 1501 return ssl_hs_error; 1502 } 1503 1504 if (hs->next_proto_neg_seen) { 1505 static const uint8_t kZero[32] = {0}; 1506 size_t padding_len = 1507 32 - ((ssl->s3->next_proto_negotiated.size() + 2) % 32); 1508 1509 ScopedCBB cbb; 1510 CBB body, child; 1511 if (!ssl->method->init_message(ssl, cbb.get(), &body, SSL3_MT_NEXT_PROTO) || 1512 !CBB_add_u8_length_prefixed(&body, &child) || 1513 !CBB_add_bytes(&child, ssl->s3->next_proto_negotiated.data(), 1514 ssl->s3->next_proto_negotiated.size()) || 1515 !CBB_add_u8_length_prefixed(&body, &child) || 1516 !CBB_add_bytes(&child, kZero, padding_len) || 1517 !ssl_add_message_cbb(ssl, cbb.get())) { 1518 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1519 return ssl_hs_error; 1520 } 1521 } 1522 1523 if (ssl->s3->tlsext_channel_id_valid) { 1524 ScopedCBB cbb; 1525 CBB body; 1526 if (!ssl->method->init_message(ssl, cbb.get(), &body, SSL3_MT_CHANNEL_ID) || 1527 !tls1_write_channel_id(hs, &body) || 1528 !ssl_add_message_cbb(ssl, cbb.get())) { 1529 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1530 return ssl_hs_error; 1531 } 1532 } 1533 1534 if (!ssl_send_finished(hs)) { 1535 return ssl_hs_error; 1536 } 1537 1538 hs->state = state_finish_flight; 1539 return ssl_hs_flush; 1540 } 1541 1542 static bool can_false_start(const SSL_HANDSHAKE *hs) { 1543 SSL *const ssl = hs->ssl; 1544 1545 // False Start only for TLS 1.2 with an ECDHE+AEAD cipher. 1546 if (SSL_is_dtls(ssl) || 1547 SSL_version(ssl) != TLS1_2_VERSION || 1548 hs->new_cipher->algorithm_mkey != SSL_kECDHE || 1549 hs->new_cipher->algorithm_mac != SSL_AEAD) { 1550 return false; 1551 } 1552 1553 // Additionally require ALPN or NPN by default. 1554 // 1555 // TODO(davidben): Can this constraint be relaxed globally now that cipher 1556 // suite requirements have been relaxed? 1557 if (!ssl->ctx->false_start_allowed_without_alpn && 1558 ssl->s3->alpn_selected.empty() && 1559 ssl->s3->next_proto_negotiated.empty()) { 1560 return false; 1561 } 1562 1563 return true; 1564 } 1565 1566 static enum ssl_hs_wait_t do_finish_flight(SSL_HANDSHAKE *hs) { 1567 SSL *const ssl = hs->ssl; 1568 if (ssl->session != NULL) { 1569 hs->state = state_finish_client_handshake; 1570 return ssl_hs_ok; 1571 } 1572 1573 // This is a full handshake. If it involves ChannelID, then record the 1574 // handshake hashes at this point in the session so that any resumption of 1575 // this session with ChannelID can sign those hashes. 1576 if (!tls1_record_handshake_hashes_for_channel_id(hs)) { 1577 return ssl_hs_error; 1578 } 1579 1580 hs->state = state_read_session_ticket; 1581 1582 if ((SSL_get_mode(ssl) & SSL_MODE_ENABLE_FALSE_START) && 1583 can_false_start(hs) && 1584 // No False Start on renegotiation (would complicate the state machine). 1585 !ssl->s3->initial_handshake_complete) { 1586 hs->in_false_start = true; 1587 hs->can_early_write = true; 1588 return ssl_hs_early_return; 1589 } 1590 1591 return ssl_hs_ok; 1592 } 1593 1594 static enum ssl_hs_wait_t do_read_session_ticket(SSL_HANDSHAKE *hs) { 1595 SSL *const ssl = hs->ssl; 1596 1597 if (!hs->ticket_expected) { 1598 hs->state = state_process_change_cipher_spec; 1599 return ssl_hs_read_change_cipher_spec; 1600 } 1601 1602 SSLMessage msg; 1603 if (!ssl->method->get_message(ssl, &msg)) { 1604 return ssl_hs_read_message; 1605 } 1606 1607 if (!ssl_check_message_type(ssl, msg, SSL3_MT_NEW_SESSION_TICKET) || 1608 !ssl_hash_message(hs, msg)) { 1609 return ssl_hs_error; 1610 } 1611 1612 CBS new_session_ticket = msg.body, ticket; 1613 uint32_t tlsext_tick_lifetime_hint; 1614 if (!CBS_get_u32(&new_session_ticket, &tlsext_tick_lifetime_hint) || 1615 !CBS_get_u16_length_prefixed(&new_session_ticket, &ticket) || 1616 CBS_len(&new_session_ticket) != 0) { 1617 ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1618 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1619 return ssl_hs_error; 1620 } 1621 1622 if (CBS_len(&ticket) == 0) { 1623 // RFC 5077 allows a server to change its mind and send no ticket after 1624 // negotiating the extension. The value of |ticket_expected| is checked in 1625 // |ssl_update_cache| so is cleared here to avoid an unnecessary update. 1626 hs->ticket_expected = false; 1627 ssl->method->next_message(ssl); 1628 hs->state = state_process_change_cipher_spec; 1629 return ssl_hs_read_change_cipher_spec; 1630 } 1631 1632 SSL_SESSION *session = hs->new_session.get(); 1633 UniquePtr<SSL_SESSION> renewed_session; 1634 if (ssl->session != NULL) { 1635 // The server is sending a new ticket for an existing session. Sessions are 1636 // immutable once established, so duplicate all but the ticket of the 1637 // existing session. 1638 renewed_session = 1639 SSL_SESSION_dup(ssl->session, SSL_SESSION_INCLUDE_NONAUTH); 1640 if (!renewed_session) { 1641 // This should never happen. 1642 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1643 return ssl_hs_error; 1644 } 1645 session = renewed_session.get(); 1646 } 1647 1648 // |tlsext_tick_lifetime_hint| is measured from when the ticket was issued. 1649 ssl_session_rebase_time(ssl, session); 1650 1651 if (!CBS_stow(&ticket, &session->tlsext_tick, &session->tlsext_ticklen)) { 1652 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1653 return ssl_hs_error; 1654 } 1655 session->tlsext_tick_lifetime_hint = tlsext_tick_lifetime_hint; 1656 1657 // Generate a session ID for this session based on the session ticket. We use 1658 // the session ID mechanism for detecting ticket resumption. This also fits in 1659 // with assumptions elsewhere in OpenSSL. 1660 if (!EVP_Digest(CBS_data(&ticket), CBS_len(&ticket), 1661 session->session_id, &session->session_id_length, 1662 EVP_sha256(), NULL)) { 1663 return ssl_hs_error; 1664 } 1665 1666 if (renewed_session) { 1667 session->not_resumable = 0; 1668 SSL_SESSION_free(ssl->session); 1669 ssl->session = renewed_session.release(); 1670 } 1671 1672 ssl->method->next_message(ssl); 1673 hs->state = state_process_change_cipher_spec; 1674 return ssl_hs_read_change_cipher_spec; 1675 } 1676 1677 static enum ssl_hs_wait_t do_process_change_cipher_spec(SSL_HANDSHAKE *hs) { 1678 if (!tls1_change_cipher_state(hs, evp_aead_open)) { 1679 return ssl_hs_error; 1680 } 1681 1682 hs->state = state_read_server_finished; 1683 return ssl_hs_ok; 1684 } 1685 1686 static enum ssl_hs_wait_t do_read_server_finished(SSL_HANDSHAKE *hs) { 1687 SSL *const ssl = hs->ssl; 1688 enum ssl_hs_wait_t wait = ssl_get_finished(hs); 1689 if (wait != ssl_hs_ok) { 1690 return wait; 1691 } 1692 1693 if (ssl->session != NULL) { 1694 hs->state = state_send_client_finished; 1695 return ssl_hs_ok; 1696 } 1697 1698 hs->state = state_finish_client_handshake; 1699 return ssl_hs_ok; 1700 } 1701 1702 static enum ssl_hs_wait_t do_finish_client_handshake(SSL_HANDSHAKE *hs) { 1703 SSL *const ssl = hs->ssl; 1704 1705 ssl->method->on_handshake_complete(ssl); 1706 1707 if (ssl->session != NULL) { 1708 SSL_SESSION_up_ref(ssl->session); 1709 ssl->s3->established_session.reset(ssl->session); 1710 } else { 1711 // We make a copy of the session in order to maintain the immutability 1712 // of the new established_session due to False Start. The caller may 1713 // have taken a reference to the temporary session. 1714 ssl->s3->established_session = 1715 SSL_SESSION_dup(hs->new_session.get(), SSL_SESSION_DUP_ALL); 1716 if (!ssl->s3->established_session) { 1717 return ssl_hs_error; 1718 } 1719 // Renegotiations do not participate in session resumption. 1720 if (!ssl->s3->initial_handshake_complete) { 1721 ssl->s3->established_session->not_resumable = 0; 1722 } 1723 1724 hs->new_session.reset(); 1725 } 1726 1727 hs->handshake_finalized = true; 1728 ssl->s3->initial_handshake_complete = true; 1729 ssl_update_cache(hs, SSL_SESS_CACHE_CLIENT); 1730 1731 hs->state = state_done; 1732 return ssl_hs_ok; 1733 } 1734 1735 enum ssl_hs_wait_t ssl_client_handshake(SSL_HANDSHAKE *hs) { 1736 while (hs->state != state_done) { 1737 enum ssl_hs_wait_t ret = ssl_hs_error; 1738 enum ssl_client_hs_state_t state = 1739 static_cast<enum ssl_client_hs_state_t>(hs->state); 1740 switch (state) { 1741 case state_start_connect: 1742 ret = do_start_connect(hs); 1743 break; 1744 case state_enter_early_data: 1745 ret = do_enter_early_data(hs); 1746 break; 1747 case state_read_hello_verify_request: 1748 ret = do_read_hello_verify_request(hs); 1749 break; 1750 case state_read_server_hello: 1751 ret = do_read_server_hello(hs); 1752 break; 1753 case state_tls13: 1754 ret = do_tls13(hs); 1755 break; 1756 case state_read_server_certificate: 1757 ret = do_read_server_certificate(hs); 1758 break; 1759 case state_read_certificate_status: 1760 ret = do_read_certificate_status(hs); 1761 break; 1762 case state_verify_server_certificate: 1763 ret = do_verify_server_certificate(hs); 1764 break; 1765 case state_read_server_key_exchange: 1766 ret = do_read_server_key_exchange(hs); 1767 break; 1768 case state_read_certificate_request: 1769 ret = do_read_certificate_request(hs); 1770 break; 1771 case state_read_server_hello_done: 1772 ret = do_read_server_hello_done(hs); 1773 break; 1774 case state_send_client_certificate: 1775 ret = do_send_client_certificate(hs); 1776 break; 1777 case state_send_client_key_exchange: 1778 ret = do_send_client_key_exchange(hs); 1779 break; 1780 case state_send_client_certificate_verify: 1781 ret = do_send_client_certificate_verify(hs); 1782 break; 1783 case state_send_client_finished: 1784 ret = do_send_client_finished(hs); 1785 break; 1786 case state_finish_flight: 1787 ret = do_finish_flight(hs); 1788 break; 1789 case state_read_session_ticket: 1790 ret = do_read_session_ticket(hs); 1791 break; 1792 case state_process_change_cipher_spec: 1793 ret = do_process_change_cipher_spec(hs); 1794 break; 1795 case state_read_server_finished: 1796 ret = do_read_server_finished(hs); 1797 break; 1798 case state_finish_client_handshake: 1799 ret = do_finish_client_handshake(hs); 1800 break; 1801 case state_done: 1802 ret = ssl_hs_ok; 1803 break; 1804 } 1805 1806 if (hs->state != state) { 1807 ssl_do_info_callback(hs->ssl, SSL_CB_CONNECT_LOOP, 1); 1808 } 1809 1810 if (ret != ssl_hs_ok) { 1811 return ret; 1812 } 1813 } 1814 1815 ssl_do_info_callback(hs->ssl, SSL_CB_HANDSHAKE_DONE, 1); 1816 return ssl_hs_ok; 1817 } 1818 1819 const char *ssl_client_handshake_state(SSL_HANDSHAKE *hs) { 1820 enum ssl_client_hs_state_t state = 1821 static_cast<enum ssl_client_hs_state_t>(hs->state); 1822 switch (state) { 1823 case state_start_connect: 1824 return "TLS client start_connect"; 1825 case state_enter_early_data: 1826 return "TLS client enter_early_data"; 1827 case state_read_hello_verify_request: 1828 return "TLS client read_hello_verify_request"; 1829 case state_read_server_hello: 1830 return "TLS client read_server_hello"; 1831 case state_tls13: 1832 return tls13_client_handshake_state(hs); 1833 case state_read_server_certificate: 1834 return "TLS client read_server_certificate"; 1835 case state_read_certificate_status: 1836 return "TLS client read_certificate_status"; 1837 case state_verify_server_certificate: 1838 return "TLS client verify_server_certificate"; 1839 case state_read_server_key_exchange: 1840 return "TLS client read_server_key_exchange"; 1841 case state_read_certificate_request: 1842 return "TLS client read_certificate_request"; 1843 case state_read_server_hello_done: 1844 return "TLS client read_server_hello_done"; 1845 case state_send_client_certificate: 1846 return "TLS client send_client_certificate"; 1847 case state_send_client_key_exchange: 1848 return "TLS client send_client_key_exchange"; 1849 case state_send_client_certificate_verify: 1850 return "TLS client send_client_certificate_verify"; 1851 case state_send_client_finished: 1852 return "TLS client send_client_finished"; 1853 case state_finish_flight: 1854 return "TLS client finish_flight"; 1855 case state_read_session_ticket: 1856 return "TLS client read_session_ticket"; 1857 case state_process_change_cipher_spec: 1858 return "TLS client process_change_cipher_spec"; 1859 case state_read_server_finished: 1860 return "TLS client read_server_finished"; 1861 case state_finish_client_handshake: 1862 return "TLS client finish_client_handshake"; 1863 case state_done: 1864 return "TLS client done"; 1865 } 1866 1867 return "TLS client unknown"; 1868 } 1869 1870 } 1871
