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 <string.h> 154 155 #include <openssl/aead.h> 156 #include <openssl/bn.h> 157 #include <openssl/buf.h> 158 #include <openssl/bytestring.h> 159 #include <openssl/ec_key.h> 160 #include <openssl/ecdsa.h> 161 #include <openssl/err.h> 162 #include <openssl/evp.h> 163 #include <openssl/md5.h> 164 #include <openssl/mem.h> 165 #include <openssl/rand.h> 166 167 #include "../crypto/internal.h" 168 #include "internal.h" 169 170 171 static int ssl3_send_client_hello(SSL_HANDSHAKE *hs); 172 static int dtls1_get_hello_verify_request(SSL_HANDSHAKE *hs); 173 static int ssl3_get_server_hello(SSL_HANDSHAKE *hs); 174 static int ssl3_get_server_certificate(SSL_HANDSHAKE *hs); 175 static int ssl3_get_cert_status(SSL_HANDSHAKE *hs); 176 static int ssl3_verify_server_cert(SSL_HANDSHAKE *hs); 177 static int ssl3_get_server_key_exchange(SSL_HANDSHAKE *hs); 178 static int ssl3_get_certificate_request(SSL_HANDSHAKE *hs); 179 static int ssl3_get_server_hello_done(SSL_HANDSHAKE *hs); 180 static int ssl3_send_client_certificate(SSL_HANDSHAKE *hs); 181 static int ssl3_send_client_key_exchange(SSL_HANDSHAKE *hs); 182 static int ssl3_send_cert_verify(SSL_HANDSHAKE *hs); 183 static int ssl3_send_next_proto(SSL_HANDSHAKE *hs); 184 static int ssl3_send_channel_id(SSL_HANDSHAKE *hs); 185 static int ssl3_get_new_session_ticket(SSL_HANDSHAKE *hs); 186 187 int ssl3_connect(SSL_HANDSHAKE *hs) { 188 SSL *const ssl = hs->ssl; 189 int ret = -1; 190 191 assert(ssl->handshake_func == ssl3_connect); 192 assert(!ssl->server); 193 194 for (;;) { 195 int state = hs->state; 196 197 switch (hs->state) { 198 case SSL_ST_INIT: 199 ssl_do_info_callback(ssl, SSL_CB_HANDSHAKE_START, 1); 200 hs->state = SSL3_ST_CW_CLNT_HELLO_A; 201 break; 202 203 case SSL3_ST_CW_CLNT_HELLO_A: 204 ret = ssl3_send_client_hello(hs); 205 if (ret <= 0) { 206 goto end; 207 } 208 209 if (!SSL_is_dtls(ssl) || ssl->d1->send_cookie) { 210 if (hs->early_data_offered) { 211 if (!tls13_init_early_key_schedule(hs) || 212 !tls13_advance_key_schedule(hs, ssl->session->master_key, 213 ssl->session->master_key_length) || 214 !tls13_derive_early_secrets(hs) || 215 !tls13_set_traffic_key(ssl, evp_aead_seal, 216 hs->early_traffic_secret, 217 hs->hash_len)) { 218 ret = -1; 219 goto end; 220 } 221 hs->next_state = SSL3_ST_WRITE_EARLY_DATA; 222 } else { 223 hs->next_state = SSL3_ST_CR_SRVR_HELLO_A; 224 } 225 } else { 226 hs->next_state = DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A; 227 } 228 hs->state = SSL3_ST_CW_FLUSH; 229 break; 230 231 case DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A: 232 assert(SSL_is_dtls(ssl)); 233 ret = dtls1_get_hello_verify_request(hs); 234 if (ret <= 0) { 235 goto end; 236 } 237 if (ssl->d1->send_cookie) { 238 ssl->method->received_flight(ssl); 239 hs->state = SSL3_ST_CW_CLNT_HELLO_A; 240 } else { 241 hs->state = SSL3_ST_CR_SRVR_HELLO_A; 242 } 243 break; 244 245 case SSL3_ST_WRITE_EARLY_DATA: 246 /* Stash the early data session, so connection properties may be queried 247 * out of it. */ 248 hs->in_early_data = 1; 249 hs->early_session = ssl->session; 250 SSL_SESSION_up_ref(ssl->session); 251 252 hs->state = SSL3_ST_CR_SRVR_HELLO_A; 253 hs->can_early_write = 1; 254 ret = 1; 255 goto end; 256 257 case SSL3_ST_CR_SRVR_HELLO_A: 258 ret = ssl3_get_server_hello(hs); 259 if (hs->state == SSL_ST_TLS13) { 260 break; 261 } 262 if (ret <= 0) { 263 goto end; 264 } 265 266 if (ssl->session != NULL) { 267 hs->state = SSL3_ST_CR_SESSION_TICKET_A; 268 } else { 269 hs->state = SSL3_ST_CR_CERT_A; 270 } 271 break; 272 273 case SSL3_ST_CR_CERT_A: 274 if (ssl_cipher_uses_certificate_auth(hs->new_cipher)) { 275 ret = ssl3_get_server_certificate(hs); 276 if (ret <= 0) { 277 goto end; 278 } 279 } 280 hs->state = SSL3_ST_CR_CERT_STATUS_A; 281 break; 282 283 case SSL3_ST_CR_CERT_STATUS_A: 284 if (hs->certificate_status_expected) { 285 ret = ssl3_get_cert_status(hs); 286 if (ret <= 0) { 287 goto end; 288 } 289 } 290 hs->state = SSL3_ST_VERIFY_SERVER_CERT; 291 break; 292 293 case SSL3_ST_VERIFY_SERVER_CERT: 294 if (ssl_cipher_uses_certificate_auth(hs->new_cipher)) { 295 ret = ssl3_verify_server_cert(hs); 296 if (ret <= 0) { 297 goto end; 298 } 299 } 300 hs->state = SSL3_ST_CR_KEY_EXCH_A; 301 break; 302 303 case SSL3_ST_CR_KEY_EXCH_A: 304 ret = ssl3_get_server_key_exchange(hs); 305 if (ret <= 0) { 306 goto end; 307 } 308 hs->state = SSL3_ST_CR_CERT_REQ_A; 309 break; 310 311 case SSL3_ST_CR_CERT_REQ_A: 312 if (ssl_cipher_uses_certificate_auth(hs->new_cipher)) { 313 ret = ssl3_get_certificate_request(hs); 314 if (ret <= 0) { 315 goto end; 316 } 317 } 318 hs->state = SSL3_ST_CR_SRVR_DONE_A; 319 break; 320 321 case SSL3_ST_CR_SRVR_DONE_A: 322 ret = ssl3_get_server_hello_done(hs); 323 if (ret <= 0) { 324 goto end; 325 } 326 ssl->method->received_flight(ssl); 327 hs->state = SSL3_ST_CW_CERT_A; 328 break; 329 330 case SSL3_ST_CW_CERT_A: 331 if (hs->cert_request) { 332 ret = ssl3_send_client_certificate(hs); 333 if (ret <= 0) { 334 goto end; 335 } 336 } 337 hs->state = SSL3_ST_CW_KEY_EXCH_A; 338 break; 339 340 case SSL3_ST_CW_KEY_EXCH_A: 341 ret = ssl3_send_client_key_exchange(hs); 342 if (ret <= 0) { 343 goto end; 344 } 345 hs->state = SSL3_ST_CW_CERT_VRFY_A; 346 break; 347 348 case SSL3_ST_CW_CERT_VRFY_A: 349 if (hs->cert_request && ssl_has_certificate(ssl)) { 350 ret = ssl3_send_cert_verify(hs); 351 if (ret <= 0) { 352 goto end; 353 } 354 } 355 hs->state = SSL3_ST_CW_CHANGE; 356 break; 357 358 case SSL3_ST_CW_CHANGE: 359 if (!ssl->method->add_change_cipher_spec(ssl) || 360 !tls1_change_cipher_state(hs, SSL3_CHANGE_CIPHER_CLIENT_WRITE)) { 361 ret = -1; 362 goto end; 363 } 364 365 hs->state = SSL3_ST_CW_NEXT_PROTO_A; 366 break; 367 368 case SSL3_ST_CW_NEXT_PROTO_A: 369 if (hs->next_proto_neg_seen) { 370 ret = ssl3_send_next_proto(hs); 371 if (ret <= 0) { 372 goto end; 373 } 374 } 375 hs->state = SSL3_ST_CW_CHANNEL_ID_A; 376 break; 377 378 case SSL3_ST_CW_CHANNEL_ID_A: 379 if (ssl->s3->tlsext_channel_id_valid) { 380 ret = ssl3_send_channel_id(hs); 381 if (ret <= 0) { 382 goto end; 383 } 384 } 385 hs->state = SSL3_ST_CW_FINISHED_A; 386 break; 387 388 case SSL3_ST_CW_FINISHED_A: 389 ret = ssl3_send_finished(hs); 390 if (ret <= 0) { 391 goto end; 392 } 393 hs->state = SSL3_ST_CW_FLUSH; 394 395 if (ssl->session != NULL) { 396 hs->next_state = SSL3_ST_FINISH_CLIENT_HANDSHAKE; 397 } else { 398 /* This is a non-resumption handshake. If it involves ChannelID, then 399 * record the handshake hashes at this point in the session so that 400 * any resumption of this session with ChannelID can sign those 401 * hashes. */ 402 ret = tls1_record_handshake_hashes_for_channel_id(hs); 403 if (ret <= 0) { 404 goto end; 405 } 406 if ((SSL_get_mode(ssl) & SSL_MODE_ENABLE_FALSE_START) && 407 ssl3_can_false_start(ssl) && 408 /* No False Start on renegotiation (would complicate the state 409 * machine). */ 410 !ssl->s3->initial_handshake_complete) { 411 hs->next_state = SSL3_ST_FALSE_START; 412 } else { 413 hs->next_state = SSL3_ST_CR_SESSION_TICKET_A; 414 } 415 } 416 break; 417 418 case SSL3_ST_FALSE_START: 419 hs->state = SSL3_ST_CR_SESSION_TICKET_A; 420 hs->in_false_start = 1; 421 hs->can_early_write = 1; 422 ret = 1; 423 goto end; 424 425 case SSL3_ST_CR_SESSION_TICKET_A: 426 if (hs->ticket_expected) { 427 ret = ssl3_get_new_session_ticket(hs); 428 if (ret <= 0) { 429 goto end; 430 } 431 } 432 hs->state = SSL3_ST_CR_CHANGE; 433 break; 434 435 case SSL3_ST_CR_CHANGE: 436 ret = ssl->method->read_change_cipher_spec(ssl); 437 if (ret <= 0) { 438 goto end; 439 } 440 441 if (!tls1_change_cipher_state(hs, SSL3_CHANGE_CIPHER_CLIENT_READ)) { 442 ret = -1; 443 goto end; 444 } 445 hs->state = SSL3_ST_CR_FINISHED_A; 446 break; 447 448 case SSL3_ST_CR_FINISHED_A: 449 ret = ssl3_get_finished(hs); 450 if (ret <= 0) { 451 goto end; 452 } 453 ssl->method->received_flight(ssl); 454 455 if (ssl->session != NULL) { 456 hs->state = SSL3_ST_CW_CHANGE; 457 } else { 458 hs->state = SSL3_ST_FINISH_CLIENT_HANDSHAKE; 459 } 460 break; 461 462 case SSL3_ST_CW_FLUSH: 463 ret = ssl->method->flush_flight(ssl); 464 if (ret <= 0) { 465 goto end; 466 } 467 hs->state = hs->next_state; 468 if (hs->state != SSL3_ST_FINISH_CLIENT_HANDSHAKE) { 469 ssl->method->expect_flight(ssl); 470 } 471 break; 472 473 case SSL_ST_TLS13: { 474 int early_return = 0; 475 ret = tls13_handshake(hs, &early_return); 476 if (ret <= 0) { 477 goto end; 478 } 479 480 if (early_return) { 481 ret = 1; 482 goto end; 483 } 484 485 hs->state = SSL3_ST_FINISH_CLIENT_HANDSHAKE; 486 break; 487 } 488 489 case SSL3_ST_FINISH_CLIENT_HANDSHAKE: 490 ssl->method->release_current_message(ssl, 1 /* free_buffer */); 491 492 SSL_SESSION_free(ssl->s3->established_session); 493 if (ssl->session != NULL) { 494 SSL_SESSION_up_ref(ssl->session); 495 ssl->s3->established_session = ssl->session; 496 } else { 497 /* We make a copy of the session in order to maintain the immutability 498 * of the new established_session due to False Start. The caller may 499 * have taken a reference to the temporary session. */ 500 ssl->s3->established_session = 501 SSL_SESSION_dup(hs->new_session, SSL_SESSION_DUP_ALL); 502 if (ssl->s3->established_session == NULL) { 503 ret = -1; 504 goto end; 505 } 506 /* Renegotiations do not participate in session resumption. */ 507 if (!ssl->s3->initial_handshake_complete) { 508 ssl->s3->established_session->not_resumable = 0; 509 } 510 511 SSL_SESSION_free(hs->new_session); 512 hs->new_session = NULL; 513 } 514 515 hs->state = SSL_ST_OK; 516 break; 517 518 case SSL_ST_OK: { 519 ssl->s3->initial_handshake_complete = 1; 520 ssl_update_cache(hs, SSL_SESS_CACHE_CLIENT); 521 522 ret = 1; 523 ssl_do_info_callback(ssl, SSL_CB_HANDSHAKE_DONE, 1); 524 goto end; 525 } 526 527 default: 528 OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_STATE); 529 ret = -1; 530 goto end; 531 } 532 533 if (hs->state != state) { 534 ssl_do_info_callback(ssl, SSL_CB_CONNECT_LOOP, 1); 535 } 536 } 537 538 end: 539 ssl_do_info_callback(ssl, SSL_CB_CONNECT_EXIT, ret); 540 return ret; 541 } 542 543 uint16_t ssl_get_grease_value(const SSL *ssl, enum ssl_grease_index_t index) { 544 /* Use the client_random for entropy. This both avoids calling |RAND_bytes| on 545 * a single byte repeatedly and ensures the values are deterministic. This 546 * allows the same ClientHello be sent twice for a HelloRetryRequest or the 547 * same group be advertised in both supported_groups and key_shares. */ 548 uint16_t ret = ssl->s3->client_random[index]; 549 /* This generates a random value of the form 0xaa, for all 0 < 16. */ 550 ret = (ret & 0xf0) | 0x0a; 551 ret |= ret << 8; 552 return ret; 553 } 554 555 /* ssl_get_client_disabled sets |*out_mask_a| and |*out_mask_k| to masks of 556 * disabled algorithms. */ 557 static void ssl_get_client_disabled(SSL *ssl, uint32_t *out_mask_a, 558 uint32_t *out_mask_k) { 559 *out_mask_a = 0; 560 *out_mask_k = 0; 561 562 /* PSK requires a client callback. */ 563 if (ssl->psk_client_callback == NULL) { 564 *out_mask_a |= SSL_aPSK; 565 *out_mask_k |= SSL_kPSK; 566 } 567 } 568 569 static int ssl_write_client_cipher_list(SSL_HANDSHAKE *hs, CBB *out) { 570 SSL *const ssl = hs->ssl; 571 uint32_t mask_a, mask_k; 572 ssl_get_client_disabled(ssl, &mask_a, &mask_k); 573 574 CBB child; 575 if (!CBB_add_u16_length_prefixed(out, &child)) { 576 return 0; 577 } 578 579 /* Add a fake cipher suite. See draft-davidben-tls-grease-01. */ 580 if (ssl->ctx->grease_enabled && 581 !CBB_add_u16(&child, ssl_get_grease_value(ssl, ssl_grease_cipher))) { 582 return 0; 583 } 584 585 /* Add TLS 1.3 ciphers. Order ChaCha20-Poly1305 relative to AES-GCM based on 586 * hardware support. */ 587 if (hs->max_version >= TLS1_3_VERSION) { 588 if (!EVP_has_aes_hardware() && 589 !CBB_add_u16(&child, TLS1_CK_CHACHA20_POLY1305_SHA256 & 0xffff)) { 590 return 0; 591 } 592 if (!CBB_add_u16(&child, TLS1_CK_AES_128_GCM_SHA256 & 0xffff) || 593 !CBB_add_u16(&child, TLS1_CK_AES_256_GCM_SHA384 & 0xffff)) { 594 return 0; 595 } 596 if (EVP_has_aes_hardware() && 597 !CBB_add_u16(&child, TLS1_CK_CHACHA20_POLY1305_SHA256 & 0xffff)) { 598 return 0; 599 } 600 } 601 602 if (hs->min_version < TLS1_3_VERSION) { 603 STACK_OF(SSL_CIPHER) *ciphers = SSL_get_ciphers(ssl); 604 int any_enabled = 0; 605 for (size_t i = 0; i < sk_SSL_CIPHER_num(ciphers); i++) { 606 const SSL_CIPHER *cipher = sk_SSL_CIPHER_value(ciphers, i); 607 /* Skip disabled ciphers */ 608 if ((cipher->algorithm_mkey & mask_k) || 609 (cipher->algorithm_auth & mask_a)) { 610 continue; 611 } 612 if (SSL_CIPHER_get_min_version(cipher) > hs->max_version || 613 SSL_CIPHER_get_max_version(cipher) < hs->min_version) { 614 continue; 615 } 616 any_enabled = 1; 617 if (!CBB_add_u16(&child, ssl_cipher_get_value(cipher))) { 618 return 0; 619 } 620 } 621 622 /* If all ciphers were disabled, return the error to the caller. */ 623 if (!any_enabled && hs->max_version < TLS1_3_VERSION) { 624 OPENSSL_PUT_ERROR(SSL, SSL_R_NO_CIPHERS_AVAILABLE); 625 return 0; 626 } 627 } 628 629 /* For SSLv3, the SCSV is added. Otherwise the renegotiation extension is 630 * added. */ 631 if (hs->max_version == SSL3_VERSION && 632 !ssl->s3->initial_handshake_complete) { 633 if (!CBB_add_u16(&child, SSL3_CK_SCSV & 0xffff)) { 634 return 0; 635 } 636 } 637 638 if (ssl->mode & SSL_MODE_SEND_FALLBACK_SCSV) { 639 if (!CBB_add_u16(&child, SSL3_CK_FALLBACK_SCSV & 0xffff)) { 640 return 0; 641 } 642 } 643 644 return CBB_flush(out); 645 } 646 647 int ssl_write_client_hello(SSL_HANDSHAKE *hs) { 648 SSL *const ssl = hs->ssl; 649 bssl::ScopedCBB cbb; 650 CBB body; 651 if (!ssl->method->init_message(ssl, cbb.get(), &body, SSL3_MT_CLIENT_HELLO)) { 652 return 0; 653 } 654 655 /* Renegotiations do not participate in session resumption. */ 656 int has_session_id = ssl->session != NULL && 657 !ssl->s3->initial_handshake_complete && 658 ssl->session->session_id_length > 0; 659 660 CBB child; 661 if (!CBB_add_u16(&body, hs->client_version) || 662 !CBB_add_bytes(&body, ssl->s3->client_random, SSL3_RANDOM_SIZE) || 663 !CBB_add_u8_length_prefixed(&body, &child)) { 664 return 0; 665 } 666 667 if (has_session_id) { 668 if (!CBB_add_bytes(&child, ssl->session->session_id, 669 ssl->session->session_id_length)) { 670 return 0; 671 } 672 } else { 673 /* In TLS 1.3 experimental encodings, send a fake placeholder session ID 674 * when we do not otherwise have one to send. */ 675 if (hs->max_version >= TLS1_3_VERSION && 676 ssl->tls13_variant == tls13_experiment && 677 !CBB_add_bytes(&child, hs->session_id, hs->session_id_len)) { 678 return 0; 679 } 680 } 681 682 if (SSL_is_dtls(ssl)) { 683 if (!CBB_add_u8_length_prefixed(&body, &child) || 684 !CBB_add_bytes(&child, ssl->d1->cookie, ssl->d1->cookie_len)) { 685 return 0; 686 } 687 } 688 689 size_t header_len = 690 SSL_is_dtls(ssl) ? DTLS1_HM_HEADER_LENGTH : SSL3_HM_HEADER_LENGTH; 691 if (!ssl_write_client_cipher_list(hs, &body) || 692 !CBB_add_u8(&body, 1 /* one compression method */) || 693 !CBB_add_u8(&body, 0 /* null compression */) || 694 !ssl_add_clienthello_tlsext(hs, &body, header_len + CBB_len(&body))) { 695 return 0; 696 } 697 698 uint8_t *msg = NULL; 699 size_t len; 700 if (!ssl->method->finish_message(ssl, cbb.get(), &msg, &len)) { 701 return 0; 702 } 703 704 /* Now that the length prefixes have been computed, fill in the placeholder 705 * PSK binder. */ 706 if (hs->needs_psk_binder && 707 !tls13_write_psk_binder(hs, msg, len)) { 708 OPENSSL_free(msg); 709 return 0; 710 } 711 712 return ssl->method->add_message(ssl, msg, len); 713 } 714 715 static int ssl3_send_client_hello(SSL_HANDSHAKE *hs) { 716 SSL *const ssl = hs->ssl; 717 /* The handshake buffer is reset on every ClientHello. Notably, in DTLS, we 718 * may send multiple ClientHellos if we receive HelloVerifyRequest. */ 719 if (!SSL_TRANSCRIPT_init(&hs->transcript)) { 720 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 721 return -1; 722 } 723 724 /* Freeze the version range. */ 725 if (!ssl_get_version_range(ssl, &hs->min_version, &hs->max_version)) { 726 return -1; 727 } 728 729 /* Always advertise the ClientHello version from the original maximum version, 730 * even on renegotiation. The static RSA key exchange uses this field, and 731 * some servers fail when it changes across handshakes. */ 732 if (SSL_is_dtls(hs->ssl)) { 733 hs->client_version = 734 hs->max_version >= TLS1_2_VERSION ? DTLS1_2_VERSION : DTLS1_VERSION; 735 } else { 736 hs->client_version = 737 hs->max_version >= TLS1_2_VERSION ? TLS1_2_VERSION : hs->max_version; 738 } 739 740 /* If the configured session has expired or was created at a disabled 741 * version, drop it. */ 742 if (ssl->session != NULL) { 743 if (ssl->session->is_server || 744 !ssl_supports_version(hs, ssl->session->ssl_version) || 745 (ssl->session->session_id_length == 0 && 746 ssl->session->tlsext_ticklen == 0) || 747 ssl->session->not_resumable || 748 !ssl_session_is_time_valid(ssl, ssl->session)) { 749 ssl_set_session(ssl, NULL); 750 } 751 } 752 753 /* If resending the ClientHello in DTLS after a HelloVerifyRequest, don't 754 * renegerate the client_random. The random must be reused. */ 755 if ((!SSL_is_dtls(ssl) || !ssl->d1->send_cookie) && 756 !RAND_bytes(ssl->s3->client_random, sizeof(ssl->s3->client_random))) { 757 return -1; 758 } 759 760 /* Initialize a random session ID for the experimental TLS 1.3 variant. */ 761 if (ssl->tls13_variant == tls13_experiment) { 762 hs->session_id_len = sizeof(hs->session_id); 763 if (!RAND_bytes(hs->session_id, hs->session_id_len)) { 764 return -1; 765 } 766 } 767 768 if (!ssl_write_client_hello(hs)) { 769 return -1; 770 } 771 772 return 1; 773 } 774 775 static int dtls1_get_hello_verify_request(SSL_HANDSHAKE *hs) { 776 SSL *const ssl = hs->ssl; 777 CBS hello_verify_request, cookie; 778 uint16_t server_version; 779 780 int ret = ssl->method->ssl_get_message(ssl); 781 if (ret <= 0) { 782 return ret; 783 } 784 785 if (ssl->s3->tmp.message_type != DTLS1_MT_HELLO_VERIFY_REQUEST) { 786 ssl->d1->send_cookie = 0; 787 ssl->s3->tmp.reuse_message = 1; 788 return 1; 789 } 790 791 CBS_init(&hello_verify_request, ssl->init_msg, ssl->init_num); 792 if (!CBS_get_u16(&hello_verify_request, &server_version) || 793 !CBS_get_u8_length_prefixed(&hello_verify_request, &cookie) || 794 CBS_len(&cookie) > sizeof(ssl->d1->cookie) || 795 CBS_len(&hello_verify_request) != 0) { 796 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 797 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 798 return -1; 799 } 800 801 OPENSSL_memcpy(ssl->d1->cookie, CBS_data(&cookie), CBS_len(&cookie)); 802 ssl->d1->cookie_len = CBS_len(&cookie); 803 804 ssl->d1->send_cookie = 1; 805 return 1; 806 } 807 808 static int parse_server_version(SSL_HANDSHAKE *hs, uint16_t *out) { 809 SSL *const ssl = hs->ssl; 810 if (ssl->s3->tmp.message_type != SSL3_MT_SERVER_HELLO && 811 ssl->s3->tmp.message_type != SSL3_MT_HELLO_RETRY_REQUEST) { 812 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE); 813 OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE); 814 return 0; 815 } 816 817 CBS server_hello; 818 CBS_init(&server_hello, ssl->init_msg, ssl->init_num); 819 if (!CBS_get_u16(&server_hello, out)) { 820 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 821 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 822 return 0; 823 } 824 825 /* The server version may also be in the supported_versions extension if 826 * applicable. */ 827 if (ssl->s3->tmp.message_type != SSL3_MT_SERVER_HELLO || 828 *out != TLS1_2_VERSION) { 829 return 1; 830 } 831 832 uint8_t sid_length; 833 if (!CBS_skip(&server_hello, SSL3_RANDOM_SIZE) || 834 !CBS_get_u8(&server_hello, &sid_length) || 835 !CBS_skip(&server_hello, sid_length + 2 /* cipher_suite */ + 836 1 /* compression_method */)) { 837 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 838 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 839 return 0; 840 } 841 842 /* The extensions block may not be present. */ 843 if (CBS_len(&server_hello) == 0) { 844 return 1; 845 } 846 847 CBS extensions; 848 if (!CBS_get_u16_length_prefixed(&server_hello, &extensions) || 849 CBS_len(&server_hello) != 0) { 850 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 851 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 852 return 0; 853 } 854 855 int have_supported_versions; 856 CBS supported_versions; 857 const SSL_EXTENSION_TYPE ext_types[] = { 858 {TLSEXT_TYPE_supported_versions, &have_supported_versions, 859 &supported_versions}, 860 }; 861 862 uint8_t alert = SSL_AD_DECODE_ERROR; 863 if (!ssl_parse_extensions(&extensions, &alert, ext_types, 864 OPENSSL_ARRAY_SIZE(ext_types), 865 1 /* ignore unknown */)) { 866 ssl3_send_alert(ssl, SSL3_AL_FATAL, alert); 867 return 0; 868 } 869 870 if (have_supported_versions && 871 (!CBS_get_u16(&supported_versions, out) || 872 CBS_len(&supported_versions) != 0)) { 873 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 874 return 0; 875 } 876 877 return 1; 878 } 879 880 static int ssl3_get_server_hello(SSL_HANDSHAKE *hs) { 881 SSL *const ssl = hs->ssl; 882 int ret = ssl->method->ssl_get_message(ssl); 883 if (ret <= 0) { 884 uint32_t err = ERR_peek_error(); 885 if (ERR_GET_LIB(err) == ERR_LIB_SSL && 886 ERR_GET_REASON(err) == SSL_R_SSLV3_ALERT_HANDSHAKE_FAILURE) { 887 /* Add a dedicated error code to the queue for a handshake_failure alert 888 * in response to ClientHello. This matches NSS's client behavior and 889 * gives a better error on a (probable) failure to negotiate initial 890 * parameters. Note: this error code comes after the original one. 891 * 892 * See https://crbug.com/446505. */ 893 OPENSSL_PUT_ERROR(SSL, SSL_R_HANDSHAKE_FAILURE_ON_CLIENT_HELLO); 894 } 895 return ret; 896 } 897 898 uint16_t server_version; 899 if (!parse_server_version(hs, &server_version)) { 900 return -1; 901 } 902 903 if (!ssl_supports_version(hs, server_version)) { 904 OPENSSL_PUT_ERROR(SSL, SSL_R_UNSUPPORTED_PROTOCOL); 905 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_PROTOCOL_VERSION); 906 return -1; 907 } 908 909 assert(ssl->s3->have_version == ssl->s3->initial_handshake_complete); 910 if (!ssl->s3->have_version) { 911 ssl->version = server_version; 912 /* At this point, the connection's version is known and ssl->version is 913 * fixed. Begin enforcing the record-layer version. */ 914 ssl->s3->have_version = 1; 915 } else if (server_version != ssl->version) { 916 OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_SSL_VERSION); 917 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_PROTOCOL_VERSION); 918 return -1; 919 } 920 921 if (ssl3_protocol_version(ssl) >= TLS1_3_VERSION) { 922 hs->state = SSL_ST_TLS13; 923 hs->do_tls13_handshake = tls13_client_handshake; 924 return 1; 925 } 926 927 if (hs->early_data_offered) { 928 OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_VERSION_ON_EARLY_DATA); 929 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_PROTOCOL_VERSION); 930 return -1; 931 } 932 933 ssl_clear_tls13_state(hs); 934 935 if (!ssl_check_message_type(ssl, SSL3_MT_SERVER_HELLO)) { 936 return -1; 937 } 938 939 CBS server_hello, server_random, session_id; 940 uint16_t cipher_suite; 941 uint8_t compression_method; 942 CBS_init(&server_hello, ssl->init_msg, ssl->init_num); 943 if (!CBS_skip(&server_hello, 2 /* version */) || 944 !CBS_get_bytes(&server_hello, &server_random, SSL3_RANDOM_SIZE) || 945 !CBS_get_u8_length_prefixed(&server_hello, &session_id) || 946 CBS_len(&session_id) > SSL3_SESSION_ID_SIZE || 947 !CBS_get_u16(&server_hello, &cipher_suite) || 948 !CBS_get_u8(&server_hello, &compression_method)) { 949 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 950 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 951 return -1; 952 } 953 954 /* Copy over the server random. */ 955 OPENSSL_memcpy(ssl->s3->server_random, CBS_data(&server_random), 956 SSL3_RANDOM_SIZE); 957 958 /* TODO(davidben): Implement the TLS 1.1 and 1.2 downgrade sentinels once TLS 959 * 1.3 is finalized and we are not implementing a draft version. */ 960 961 if (!ssl->s3->initial_handshake_complete && ssl->session != NULL && 962 ssl->session->session_id_length != 0 && 963 CBS_mem_equal(&session_id, ssl->session->session_id, 964 ssl->session->session_id_length)) { 965 ssl->s3->session_reused = 1; 966 } else { 967 /* The session wasn't resumed. Create a fresh SSL_SESSION to 968 * fill out. */ 969 ssl_set_session(ssl, NULL); 970 if (!ssl_get_new_session(hs, 0 /* client */)) { 971 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); 972 return -1; 973 } 974 /* Note: session_id could be empty. */ 975 hs->new_session->session_id_length = CBS_len(&session_id); 976 OPENSSL_memcpy(hs->new_session->session_id, CBS_data(&session_id), 977 CBS_len(&session_id)); 978 } 979 980 const SSL_CIPHER *c = SSL_get_cipher_by_value(cipher_suite); 981 if (c == NULL) { 982 /* unknown cipher */ 983 OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_CIPHER_RETURNED); 984 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 985 return -1; 986 } 987 988 /* The cipher must be allowed in the selected version and enabled. */ 989 uint32_t mask_a, mask_k; 990 ssl_get_client_disabled(ssl, &mask_a, &mask_k); 991 if ((c->algorithm_mkey & mask_k) || (c->algorithm_auth & mask_a) || 992 SSL_CIPHER_get_min_version(c) > ssl3_protocol_version(ssl) || 993 SSL_CIPHER_get_max_version(c) < ssl3_protocol_version(ssl) || 994 !sk_SSL_CIPHER_find(SSL_get_ciphers(ssl), NULL, c)) { 995 OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CIPHER_RETURNED); 996 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 997 return -1; 998 } 999 1000 if (ssl->session != NULL) { 1001 if (ssl->session->ssl_version != ssl->version) { 1002 OPENSSL_PUT_ERROR(SSL, SSL_R_OLD_SESSION_VERSION_NOT_RETURNED); 1003 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 1004 return -1; 1005 } 1006 if (ssl->session->cipher != c) { 1007 OPENSSL_PUT_ERROR(SSL, SSL_R_OLD_SESSION_CIPHER_NOT_RETURNED); 1008 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 1009 return -1; 1010 } 1011 if (!ssl_session_is_context_valid(ssl, ssl->session)) { 1012 /* This is actually a client application bug. */ 1013 OPENSSL_PUT_ERROR(SSL, 1014 SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT); 1015 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 1016 return -1; 1017 } 1018 } else { 1019 hs->new_session->cipher = c; 1020 } 1021 hs->new_cipher = c; 1022 1023 /* Now that the cipher is known, initialize the handshake hash and hash the 1024 * ServerHello. */ 1025 if (!SSL_TRANSCRIPT_init_hash(&hs->transcript, ssl3_protocol_version(ssl), 1026 c->algorithm_prf) || 1027 !ssl_hash_current_message(hs)) { 1028 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); 1029 return -1; 1030 } 1031 1032 /* If doing a full handshake, the server may request a client certificate 1033 * which requires hashing the handshake transcript. Otherwise, the handshake 1034 * buffer may be released. */ 1035 if (ssl->session != NULL || 1036 !ssl_cipher_uses_certificate_auth(hs->new_cipher)) { 1037 SSL_TRANSCRIPT_free_buffer(&hs->transcript); 1038 } 1039 1040 /* Only the NULL compression algorithm is supported. */ 1041 if (compression_method != 0) { 1042 OPENSSL_PUT_ERROR(SSL, SSL_R_UNSUPPORTED_COMPRESSION_ALGORITHM); 1043 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 1044 return -1; 1045 } 1046 1047 /* TLS extensions */ 1048 if (!ssl_parse_serverhello_tlsext(hs, &server_hello)) { 1049 OPENSSL_PUT_ERROR(SSL, SSL_R_PARSE_TLSEXT); 1050 return -1; 1051 } 1052 1053 /* There should be nothing left over in the record. */ 1054 if (CBS_len(&server_hello) != 0) { 1055 /* wrong packet length */ 1056 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1057 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1058 return -1; 1059 } 1060 1061 if (ssl->session != NULL && 1062 hs->extended_master_secret != ssl->session->extended_master_secret) { 1063 if (ssl->session->extended_master_secret) { 1064 OPENSSL_PUT_ERROR(SSL, SSL_R_RESUMED_EMS_SESSION_WITHOUT_EMS_EXTENSION); 1065 } else { 1066 OPENSSL_PUT_ERROR(SSL, SSL_R_RESUMED_NON_EMS_SESSION_WITH_EMS_EXTENSION); 1067 } 1068 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); 1069 return -1; 1070 } 1071 1072 return 1; 1073 } 1074 1075 static int ssl3_get_server_certificate(SSL_HANDSHAKE *hs) { 1076 SSL *const ssl = hs->ssl; 1077 int ret = ssl->method->ssl_get_message(ssl); 1078 if (ret <= 0) { 1079 return ret; 1080 } 1081 1082 if (!ssl_check_message_type(ssl, SSL3_MT_CERTIFICATE) || 1083 !ssl_hash_current_message(hs)) { 1084 return -1; 1085 } 1086 1087 CBS cbs; 1088 CBS_init(&cbs, ssl->init_msg, ssl->init_num); 1089 1090 uint8_t alert = SSL_AD_DECODE_ERROR; 1091 sk_CRYPTO_BUFFER_pop_free(hs->new_session->certs, CRYPTO_BUFFER_free); 1092 EVP_PKEY_free(hs->peer_pubkey); 1093 hs->peer_pubkey = NULL; 1094 hs->new_session->certs = ssl_parse_cert_chain(&alert, &hs->peer_pubkey, NULL, 1095 &cbs, ssl->ctx->pool); 1096 if (hs->new_session->certs == NULL) { 1097 ssl3_send_alert(ssl, SSL3_AL_FATAL, alert); 1098 return -1; 1099 } 1100 1101 if (sk_CRYPTO_BUFFER_num(hs->new_session->certs) == 0 || 1102 CBS_len(&cbs) != 0 || 1103 !ssl->ctx->x509_method->session_cache_objects(hs->new_session)) { 1104 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1105 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1106 return -1; 1107 } 1108 1109 if (!ssl_check_leaf_certificate( 1110 hs, hs->peer_pubkey, 1111 sk_CRYPTO_BUFFER_value(hs->new_session->certs, 0))) { 1112 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 1113 return -1; 1114 } 1115 1116 return 1; 1117 } 1118 1119 static int ssl3_get_cert_status(SSL_HANDSHAKE *hs) { 1120 SSL *const ssl = hs->ssl; 1121 int ret = ssl->method->ssl_get_message(ssl); 1122 if (ret <= 0) { 1123 return ret; 1124 } 1125 1126 if (ssl->s3->tmp.message_type != SSL3_MT_CERTIFICATE_STATUS) { 1127 /* A server may send status_request in ServerHello and then change 1128 * its mind about sending CertificateStatus. */ 1129 ssl->s3->tmp.reuse_message = 1; 1130 return 1; 1131 } 1132 1133 if (!ssl_hash_current_message(hs)) { 1134 return -1; 1135 } 1136 1137 CBS certificate_status, ocsp_response; 1138 uint8_t status_type; 1139 CBS_init(&certificate_status, ssl->init_msg, ssl->init_num); 1140 if (!CBS_get_u8(&certificate_status, &status_type) || 1141 status_type != TLSEXT_STATUSTYPE_ocsp || 1142 !CBS_get_u24_length_prefixed(&certificate_status, &ocsp_response) || 1143 CBS_len(&ocsp_response) == 0 || 1144 CBS_len(&certificate_status) != 0) { 1145 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1146 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1147 return -1; 1148 } 1149 1150 if (!CBS_stow(&ocsp_response, &hs->new_session->ocsp_response, 1151 &hs->new_session->ocsp_response_length)) { 1152 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1153 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); 1154 return -1; 1155 } 1156 1157 return 1; 1158 } 1159 1160 static int copy_bytes(uint8_t **out, size_t *out_len, const uint8_t *in, size_t in_len) { 1161 OPENSSL_free(*out); 1162 *out = nullptr; 1163 *out_len = 0; 1164 1165 if (in_len > 0) { 1166 *out = (uint8_t *)BUF_memdup(in, in_len); 1167 if (*out == nullptr) { 1168 return 0; 1169 } 1170 *out_len = in_len; 1171 } 1172 1173 return 1; 1174 } 1175 1176 static int ssl3_verify_server_cert(SSL_HANDSHAKE *hs) { 1177 SSL *const ssl = hs->ssl; 1178 const SSL_SESSION *prev_session = ssl->s3->established_session; 1179 if (prev_session != NULL) { 1180 /* If renegotiating, the server must not change the server certificate. See 1181 * https://mitls.org/pages/attacks/3SHAKE. We never resume on renegotiation, 1182 * so this check is sufficient to ensure the reported peer certificate never 1183 * changes on renegotiation. */ 1184 assert(!ssl->server); 1185 if (sk_CRYPTO_BUFFER_num(prev_session->certs) != 1186 sk_CRYPTO_BUFFER_num(hs->new_session->certs)) { 1187 OPENSSL_PUT_ERROR(SSL, SSL_R_SERVER_CERT_CHANGED); 1188 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 1189 return -1; 1190 } 1191 1192 for (size_t i = 0; i < sk_CRYPTO_BUFFER_num(hs->new_session->certs); i++) { 1193 const CRYPTO_BUFFER *old_cert = 1194 sk_CRYPTO_BUFFER_value(prev_session->certs, i); 1195 const CRYPTO_BUFFER *new_cert = 1196 sk_CRYPTO_BUFFER_value(hs->new_session->certs, i); 1197 if (CRYPTO_BUFFER_len(old_cert) != CRYPTO_BUFFER_len(new_cert) || 1198 OPENSSL_memcmp(CRYPTO_BUFFER_data(old_cert), 1199 CRYPTO_BUFFER_data(new_cert), 1200 CRYPTO_BUFFER_len(old_cert)) != 0) { 1201 OPENSSL_PUT_ERROR(SSL, SSL_R_SERVER_CERT_CHANGED); 1202 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 1203 return -1; 1204 } 1205 } 1206 1207 /* The certificate is identical, so we may skip re-verifying the 1208 * certificate. Since we only authenticated the previous one, copy other 1209 * authentication from the established session and ignore what was newly 1210 * received. */ 1211 if (!copy_bytes(&hs->new_session->ocsp_response, 1212 &hs->new_session->ocsp_response_length, 1213 prev_session->ocsp_response, 1214 prev_session->ocsp_response_length) || 1215 !copy_bytes(&hs->new_session->tlsext_signed_cert_timestamp_list, 1216 &hs->new_session->tlsext_signed_cert_timestamp_list_length, 1217 prev_session->tlsext_signed_cert_timestamp_list, 1218 prev_session->tlsext_signed_cert_timestamp_list_length)) { 1219 return -1; 1220 } 1221 1222 hs->new_session->verify_result = prev_session->verify_result; 1223 return 1; 1224 } 1225 1226 if (!ssl->ctx->x509_method->session_verify_cert_chain(hs->new_session, ssl)) { 1227 return -1; 1228 } 1229 1230 return 1; 1231 } 1232 1233 static int ssl3_get_server_key_exchange(SSL_HANDSHAKE *hs) { 1234 SSL *const ssl = hs->ssl; 1235 EC_KEY *ecdh = NULL; 1236 EC_POINT *srvr_ecpoint = NULL; 1237 1238 int ret = ssl->method->ssl_get_message(ssl); 1239 if (ret <= 0) { 1240 return ret; 1241 } 1242 1243 if (ssl->s3->tmp.message_type != SSL3_MT_SERVER_KEY_EXCHANGE) { 1244 /* Some ciphers (pure PSK) have an optional ServerKeyExchange message. */ 1245 if (ssl_cipher_requires_server_key_exchange(hs->new_cipher)) { 1246 OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE); 1247 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE); 1248 return -1; 1249 } 1250 1251 ssl->s3->tmp.reuse_message = 1; 1252 return 1; 1253 } 1254 1255 if (!ssl_hash_current_message(hs)) { 1256 return -1; 1257 } 1258 1259 /* Retain a copy of the original CBS to compute the signature over. */ 1260 CBS server_key_exchange; 1261 CBS_init(&server_key_exchange, ssl->init_msg, ssl->init_num); 1262 CBS server_key_exchange_orig = server_key_exchange; 1263 1264 uint32_t alg_k = hs->new_cipher->algorithm_mkey; 1265 uint32_t alg_a = hs->new_cipher->algorithm_auth; 1266 1267 if (alg_a & SSL_aPSK) { 1268 CBS psk_identity_hint; 1269 1270 /* Each of the PSK key exchanges begins with a psk_identity_hint. */ 1271 if (!CBS_get_u16_length_prefixed(&server_key_exchange, 1272 &psk_identity_hint)) { 1273 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1274 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1275 goto err; 1276 } 1277 1278 /* Store PSK identity hint for later use, hint is used in 1279 * ssl3_send_client_key_exchange. Assume that the maximum length of a PSK 1280 * identity hint can be as long as the maximum length of a PSK identity. 1281 * Also do not allow NULL characters; identities are saved as C strings. 1282 * 1283 * TODO(davidben): Should invalid hints be ignored? It's a hint rather than 1284 * a specific identity. */ 1285 if (CBS_len(&psk_identity_hint) > PSK_MAX_IDENTITY_LEN || 1286 CBS_contains_zero_byte(&psk_identity_hint)) { 1287 OPENSSL_PUT_ERROR(SSL, SSL_R_DATA_LENGTH_TOO_LONG); 1288 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); 1289 goto err; 1290 } 1291 1292 /* Save non-empty identity hints as a C string. Empty identity hints we 1293 * treat as missing. Plain PSK makes it possible to send either no hint 1294 * (omit ServerKeyExchange) or an empty hint, while ECDHE_PSK can only spell 1295 * empty hint. Having different capabilities is odd, so we interpret empty 1296 * and missing as identical. */ 1297 if (CBS_len(&psk_identity_hint) != 0 && 1298 !CBS_strdup(&psk_identity_hint, &hs->peer_psk_identity_hint)) { 1299 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1300 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); 1301 goto err; 1302 } 1303 } 1304 1305 if (alg_k & SSL_kECDHE) { 1306 /* Parse the server parameters. */ 1307 uint8_t group_type; 1308 uint16_t group_id; 1309 CBS point; 1310 if (!CBS_get_u8(&server_key_exchange, &group_type) || 1311 group_type != NAMED_CURVE_TYPE || 1312 !CBS_get_u16(&server_key_exchange, &group_id) || 1313 !CBS_get_u8_length_prefixed(&server_key_exchange, &point)) { 1314 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1315 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1316 goto err; 1317 } 1318 hs->new_session->group_id = group_id; 1319 1320 /* Ensure the group is consistent with preferences. */ 1321 if (!tls1_check_group_id(ssl, group_id)) { 1322 OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_CURVE); 1323 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 1324 goto err; 1325 } 1326 1327 /* Initialize ECDH and save the peer public key for later. */ 1328 if (!SSL_ECDH_CTX_init(&hs->ecdh_ctx, group_id) || 1329 !CBS_stow(&point, &hs->peer_key, &hs->peer_key_len)) { 1330 goto err; 1331 } 1332 } else if (!(alg_k & SSL_kPSK)) { 1333 OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE); 1334 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE); 1335 goto err; 1336 } 1337 1338 /* At this point, |server_key_exchange| contains the signature, if any, while 1339 * |server_key_exchange_orig| contains the entire message. From that, derive 1340 * a CBS containing just the parameter. */ 1341 CBS parameter; 1342 CBS_init(¶meter, CBS_data(&server_key_exchange_orig), 1343 CBS_len(&server_key_exchange_orig) - CBS_len(&server_key_exchange)); 1344 1345 /* ServerKeyExchange should be signed by the server's public key. */ 1346 if (ssl_cipher_uses_certificate_auth(hs->new_cipher)) { 1347 uint16_t signature_algorithm = 0; 1348 if (ssl3_protocol_version(ssl) >= TLS1_2_VERSION) { 1349 if (!CBS_get_u16(&server_key_exchange, &signature_algorithm)) { 1350 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1351 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1352 goto err; 1353 } 1354 uint8_t alert = SSL_AD_DECODE_ERROR; 1355 if (!tls12_check_peer_sigalg(ssl, &alert, signature_algorithm)) { 1356 ssl3_send_alert(ssl, SSL3_AL_FATAL, alert); 1357 goto err; 1358 } 1359 hs->new_session->peer_signature_algorithm = signature_algorithm; 1360 } else if (!tls1_get_legacy_signature_algorithm(&signature_algorithm, 1361 hs->peer_pubkey)) { 1362 OPENSSL_PUT_ERROR(SSL, SSL_R_PEER_ERROR_UNSUPPORTED_CERTIFICATE_TYPE); 1363 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNSUPPORTED_CERTIFICATE); 1364 goto err; 1365 } 1366 1367 /* The last field in |server_key_exchange| is the signature. */ 1368 CBS signature; 1369 if (!CBS_get_u16_length_prefixed(&server_key_exchange, &signature) || 1370 CBS_len(&server_key_exchange) != 0) { 1371 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1372 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1373 goto err; 1374 } 1375 1376 CBB transcript; 1377 uint8_t *transcript_data; 1378 size_t transcript_len; 1379 if (!CBB_init(&transcript, 2*SSL3_RANDOM_SIZE + CBS_len(¶meter)) || 1380 !CBB_add_bytes(&transcript, ssl->s3->client_random, SSL3_RANDOM_SIZE) || 1381 !CBB_add_bytes(&transcript, ssl->s3->server_random, SSL3_RANDOM_SIZE) || 1382 !CBB_add_bytes(&transcript, CBS_data(¶meter), CBS_len(¶meter)) || 1383 !CBB_finish(&transcript, &transcript_data, &transcript_len)) { 1384 CBB_cleanup(&transcript); 1385 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1386 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); 1387 goto err; 1388 } 1389 1390 int sig_ok = ssl_public_key_verify( 1391 ssl, CBS_data(&signature), CBS_len(&signature), signature_algorithm, 1392 hs->peer_pubkey, transcript_data, transcript_len); 1393 OPENSSL_free(transcript_data); 1394 1395 #if defined(BORINGSSL_UNSAFE_FUZZER_MODE) 1396 sig_ok = 1; 1397 ERR_clear_error(); 1398 #endif 1399 if (!sig_ok) { 1400 /* bad signature */ 1401 OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_SIGNATURE); 1402 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECRYPT_ERROR); 1403 goto err; 1404 } 1405 } else { 1406 /* PSK ciphers are the only supported certificate-less ciphers. */ 1407 assert(alg_a == SSL_aPSK); 1408 1409 if (CBS_len(&server_key_exchange) > 0) { 1410 OPENSSL_PUT_ERROR(SSL, SSL_R_EXTRA_DATA_IN_MESSAGE); 1411 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1412 goto err; 1413 } 1414 } 1415 return 1; 1416 1417 err: 1418 EC_POINT_free(srvr_ecpoint); 1419 EC_KEY_free(ecdh); 1420 return -1; 1421 } 1422 1423 static int ssl3_get_certificate_request(SSL_HANDSHAKE *hs) { 1424 SSL *const ssl = hs->ssl; 1425 int msg_ret = ssl->method->ssl_get_message(ssl); 1426 if (msg_ret <= 0) { 1427 return msg_ret; 1428 } 1429 1430 if (ssl->s3->tmp.message_type == SSL3_MT_SERVER_HELLO_DONE) { 1431 ssl->s3->tmp.reuse_message = 1; 1432 /* If we get here we don't need the handshake buffer as we won't be doing 1433 * client auth. */ 1434 SSL_TRANSCRIPT_free_buffer(&hs->transcript); 1435 return 1; 1436 } 1437 1438 if (!ssl_check_message_type(ssl, SSL3_MT_CERTIFICATE_REQUEST) || 1439 !ssl_hash_current_message(hs)) { 1440 return -1; 1441 } 1442 1443 CBS cbs; 1444 CBS_init(&cbs, ssl->init_msg, ssl->init_num); 1445 1446 /* Get the certificate types. */ 1447 CBS certificate_types; 1448 if (!CBS_get_u8_length_prefixed(&cbs, &certificate_types)) { 1449 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1450 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1451 return -1; 1452 } 1453 1454 if (!CBS_stow(&certificate_types, &hs->certificate_types, 1455 &hs->num_certificate_types)) { 1456 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); 1457 return -1; 1458 } 1459 1460 if (ssl3_protocol_version(ssl) >= TLS1_2_VERSION) { 1461 CBS supported_signature_algorithms; 1462 if (!CBS_get_u16_length_prefixed(&cbs, &supported_signature_algorithms) || 1463 !tls1_parse_peer_sigalgs(hs, &supported_signature_algorithms)) { 1464 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1465 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1466 return -1; 1467 } 1468 } 1469 1470 uint8_t alert = SSL_AD_DECODE_ERROR; 1471 STACK_OF(CRYPTO_BUFFER) *ca_names = 1472 ssl_parse_client_CA_list(ssl, &alert, &cbs); 1473 if (ca_names == NULL) { 1474 ssl3_send_alert(ssl, SSL3_AL_FATAL, alert); 1475 return -1; 1476 } 1477 1478 if (CBS_len(&cbs) != 0) { 1479 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1480 sk_CRYPTO_BUFFER_pop_free(ca_names, CRYPTO_BUFFER_free); 1481 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1482 return -1; 1483 } 1484 1485 hs->cert_request = 1; 1486 sk_CRYPTO_BUFFER_pop_free(hs->ca_names, CRYPTO_BUFFER_free); 1487 hs->ca_names = ca_names; 1488 ssl->ctx->x509_method->hs_flush_cached_ca_names(hs); 1489 return 1; 1490 } 1491 1492 static int ssl3_get_server_hello_done(SSL_HANDSHAKE *hs) { 1493 SSL *const ssl = hs->ssl; 1494 int ret = ssl->method->ssl_get_message(ssl); 1495 if (ret <= 0) { 1496 return ret; 1497 } 1498 1499 if (!ssl_check_message_type(ssl, SSL3_MT_SERVER_HELLO_DONE) || 1500 !ssl_hash_current_message(hs)) { 1501 return -1; 1502 } 1503 1504 /* ServerHelloDone is empty. */ 1505 if (ssl->init_num > 0) { 1506 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1507 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1508 return -1; 1509 } 1510 1511 return 1; 1512 } 1513 1514 static int ssl3_send_client_certificate(SSL_HANDSHAKE *hs) { 1515 SSL *const ssl = hs->ssl; 1516 /* Call cert_cb to update the certificate. */ 1517 if (ssl->cert->cert_cb) { 1518 int ret = ssl->cert->cert_cb(ssl, ssl->cert->cert_cb_arg); 1519 if (ret < 0) { 1520 ssl->rwstate = SSL_X509_LOOKUP; 1521 return -1; 1522 } 1523 if (ret == 0) { 1524 OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_CB_ERROR); 1525 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); 1526 return -1; 1527 } 1528 } 1529 1530 if (!ssl_has_certificate(ssl)) { 1531 /* Without a client certificate, the handshake buffer may be released. */ 1532 SSL_TRANSCRIPT_free_buffer(&hs->transcript); 1533 1534 /* In SSL 3.0, the Certificate message is replaced with a warning alert. */ 1535 if (ssl->version == SSL3_VERSION) { 1536 if (!ssl->method->add_alert(ssl, SSL3_AL_WARNING, 1537 SSL_AD_NO_CERTIFICATE)) { 1538 return -1; 1539 } 1540 return 1; 1541 } 1542 } 1543 1544 if (!ssl_on_certificate_selected(hs) || 1545 !ssl3_output_cert_chain(ssl)) { 1546 return -1; 1547 } 1548 return 1; 1549 } 1550 1551 static_assert(sizeof(size_t) >= sizeof(unsigned), 1552 "size_t is smaller than unsigned"); 1553 1554 static int ssl3_send_client_key_exchange(SSL_HANDSHAKE *hs) { 1555 SSL *const ssl = hs->ssl; 1556 bssl::ScopedCBB cbb; 1557 CBB body; 1558 if (!ssl->method->init_message(ssl, cbb.get(), &body, 1559 SSL3_MT_CLIENT_KEY_EXCHANGE)) { 1560 return -1; 1561 } 1562 1563 uint8_t *pms = NULL; 1564 size_t pms_len = 0; 1565 uint32_t alg_k = hs->new_cipher->algorithm_mkey; 1566 uint32_t alg_a = hs->new_cipher->algorithm_auth; 1567 1568 /* If using a PSK key exchange, prepare the pre-shared key. */ 1569 unsigned psk_len = 0; 1570 uint8_t psk[PSK_MAX_PSK_LEN]; 1571 if (alg_a & SSL_aPSK) { 1572 if (ssl->psk_client_callback == NULL) { 1573 OPENSSL_PUT_ERROR(SSL, SSL_R_PSK_NO_CLIENT_CB); 1574 goto err; 1575 } 1576 1577 char identity[PSK_MAX_IDENTITY_LEN + 1]; 1578 OPENSSL_memset(identity, 0, sizeof(identity)); 1579 psk_len = 1580 ssl->psk_client_callback(ssl, hs->peer_psk_identity_hint, identity, 1581 sizeof(identity), psk, sizeof(psk)); 1582 if (psk_len == 0) { 1583 OPENSSL_PUT_ERROR(SSL, SSL_R_PSK_IDENTITY_NOT_FOUND); 1584 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); 1585 goto err; 1586 } 1587 assert(psk_len <= PSK_MAX_PSK_LEN); 1588 1589 OPENSSL_free(hs->new_session->psk_identity); 1590 hs->new_session->psk_identity = BUF_strdup(identity); 1591 if (hs->new_session->psk_identity == NULL) { 1592 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1593 goto err; 1594 } 1595 1596 /* Write out psk_identity. */ 1597 CBB child; 1598 if (!CBB_add_u16_length_prefixed(&body, &child) || 1599 !CBB_add_bytes(&child, (const uint8_t *)identity, 1600 OPENSSL_strnlen(identity, sizeof(identity))) || 1601 !CBB_flush(&body)) { 1602 goto err; 1603 } 1604 } 1605 1606 /* Depending on the key exchange method, compute |pms| and |pms_len|. */ 1607 if (alg_k & SSL_kRSA) { 1608 pms_len = SSL_MAX_MASTER_KEY_LENGTH; 1609 pms = (uint8_t *)OPENSSL_malloc(pms_len); 1610 if (pms == NULL) { 1611 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1612 goto err; 1613 } 1614 1615 RSA *rsa = EVP_PKEY_get0_RSA(hs->peer_pubkey); 1616 if (rsa == NULL) { 1617 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1618 goto err; 1619 } 1620 1621 pms[0] = hs->client_version >> 8; 1622 pms[1] = hs->client_version & 0xff; 1623 if (!RAND_bytes(&pms[2], SSL_MAX_MASTER_KEY_LENGTH - 2)) { 1624 goto err; 1625 } 1626 1627 CBB child, *enc_pms = &body; 1628 size_t enc_pms_len; 1629 /* In TLS, there is a length prefix. */ 1630 if (ssl->version > SSL3_VERSION) { 1631 if (!CBB_add_u16_length_prefixed(&body, &child)) { 1632 goto err; 1633 } 1634 enc_pms = &child; 1635 } 1636 1637 uint8_t *ptr; 1638 if (!CBB_reserve(enc_pms, &ptr, RSA_size(rsa)) || 1639 !RSA_encrypt(rsa, &enc_pms_len, ptr, RSA_size(rsa), pms, pms_len, 1640 RSA_PKCS1_PADDING) || 1641 !CBB_did_write(enc_pms, enc_pms_len) || 1642 !CBB_flush(&body)) { 1643 goto err; 1644 } 1645 } else if (alg_k & SSL_kECDHE) { 1646 /* Generate a keypair and serialize the public half. */ 1647 CBB child; 1648 if (!CBB_add_u8_length_prefixed(&body, &child)) { 1649 goto err; 1650 } 1651 1652 /* Compute the premaster. */ 1653 uint8_t alert = SSL_AD_DECODE_ERROR; 1654 if (!SSL_ECDH_CTX_accept(&hs->ecdh_ctx, &child, &pms, &pms_len, &alert, 1655 hs->peer_key, hs->peer_key_len)) { 1656 ssl3_send_alert(ssl, SSL3_AL_FATAL, alert); 1657 goto err; 1658 } 1659 if (!CBB_flush(&body)) { 1660 goto err; 1661 } 1662 1663 /* The key exchange state may now be discarded. */ 1664 SSL_ECDH_CTX_cleanup(&hs->ecdh_ctx); 1665 OPENSSL_free(hs->peer_key); 1666 hs->peer_key = NULL; 1667 hs->peer_key_len = 0; 1668 } else if (alg_k & SSL_kPSK) { 1669 /* For plain PSK, other_secret is a block of 0s with the same length as 1670 * the pre-shared key. */ 1671 pms_len = psk_len; 1672 pms = (uint8_t *)OPENSSL_malloc(pms_len); 1673 if (pms == NULL) { 1674 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1675 goto err; 1676 } 1677 OPENSSL_memset(pms, 0, pms_len); 1678 } else { 1679 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); 1680 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1681 goto err; 1682 } 1683 1684 /* For a PSK cipher suite, other_secret is combined with the pre-shared 1685 * key. */ 1686 if (alg_a & SSL_aPSK) { 1687 CBB pms_cbb, child; 1688 uint8_t *new_pms; 1689 size_t new_pms_len; 1690 1691 CBB_zero(&pms_cbb); 1692 if (!CBB_init(&pms_cbb, 2 + psk_len + 2 + pms_len) || 1693 !CBB_add_u16_length_prefixed(&pms_cbb, &child) || 1694 !CBB_add_bytes(&child, pms, pms_len) || 1695 !CBB_add_u16_length_prefixed(&pms_cbb, &child) || 1696 !CBB_add_bytes(&child, psk, psk_len) || 1697 !CBB_finish(&pms_cbb, &new_pms, &new_pms_len)) { 1698 CBB_cleanup(&pms_cbb); 1699 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1700 goto err; 1701 } 1702 OPENSSL_cleanse(pms, pms_len); 1703 OPENSSL_free(pms); 1704 pms = new_pms; 1705 pms_len = new_pms_len; 1706 } 1707 1708 /* The message must be added to the finished hash before calculating the 1709 * master secret. */ 1710 if (!ssl_add_message_cbb(ssl, cbb.get())) { 1711 goto err; 1712 } 1713 1714 hs->new_session->master_key_length = tls1_generate_master_secret( 1715 hs, hs->new_session->master_key, pms, pms_len); 1716 if (hs->new_session->master_key_length == 0) { 1717 goto err; 1718 } 1719 hs->new_session->extended_master_secret = hs->extended_master_secret; 1720 OPENSSL_cleanse(pms, pms_len); 1721 OPENSSL_free(pms); 1722 1723 return 1; 1724 1725 err: 1726 if (pms != NULL) { 1727 OPENSSL_cleanse(pms, pms_len); 1728 OPENSSL_free(pms); 1729 } 1730 return -1; 1731 } 1732 1733 static int ssl3_send_cert_verify(SSL_HANDSHAKE *hs) { 1734 SSL *const ssl = hs->ssl; 1735 assert(ssl_has_private_key(ssl)); 1736 1737 bssl::ScopedCBB cbb; 1738 CBB body, child; 1739 if (!ssl->method->init_message(ssl, cbb.get(), &body, 1740 SSL3_MT_CERTIFICATE_VERIFY)) { 1741 return -1; 1742 } 1743 1744 uint16_t signature_algorithm; 1745 if (!tls1_choose_signature_algorithm(hs, &signature_algorithm)) { 1746 return -1; 1747 } 1748 if (ssl3_protocol_version(ssl) >= TLS1_2_VERSION) { 1749 /* Write out the digest type in TLS 1.2. */ 1750 if (!CBB_add_u16(&body, signature_algorithm)) { 1751 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1752 return -1; 1753 } 1754 } 1755 1756 /* Set aside space for the signature. */ 1757 const size_t max_sig_len = EVP_PKEY_size(hs->local_pubkey); 1758 uint8_t *ptr; 1759 if (!CBB_add_u16_length_prefixed(&body, &child) || 1760 !CBB_reserve(&child, &ptr, max_sig_len)) { 1761 return -1; 1762 } 1763 1764 size_t sig_len = max_sig_len; 1765 /* The SSL3 construction for CertificateVerify does not decompose into a 1766 * single final digest and signature, and must be special-cased. */ 1767 if (ssl3_protocol_version(ssl) == SSL3_VERSION) { 1768 if (ssl->cert->key_method != NULL) { 1769 OPENSSL_PUT_ERROR(SSL, SSL_R_UNSUPPORTED_PROTOCOL_FOR_CUSTOM_KEY); 1770 return -1; 1771 } 1772 1773 uint8_t digest[EVP_MAX_MD_SIZE]; 1774 size_t digest_len; 1775 if (!SSL_TRANSCRIPT_ssl3_cert_verify_hash(&hs->transcript, digest, 1776 &digest_len, hs->new_session, 1777 signature_algorithm)) { 1778 return -1; 1779 } 1780 1781 EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new(ssl->cert->privatekey, NULL); 1782 int ok = pctx != NULL && 1783 EVP_PKEY_sign_init(pctx) && 1784 EVP_PKEY_sign(pctx, ptr, &sig_len, digest, digest_len); 1785 EVP_PKEY_CTX_free(pctx); 1786 if (!ok) { 1787 return -1; 1788 } 1789 } else { 1790 switch (ssl_private_key_sign(hs, ptr, &sig_len, max_sig_len, 1791 signature_algorithm, 1792 (const uint8_t *)hs->transcript.buffer->data, 1793 hs->transcript.buffer->length)) { 1794 case ssl_private_key_success: 1795 break; 1796 case ssl_private_key_failure: 1797 return -1; 1798 case ssl_private_key_retry: 1799 ssl->rwstate = SSL_PRIVATE_KEY_OPERATION; 1800 return -1; 1801 } 1802 } 1803 1804 if (!CBB_did_write(&child, sig_len) || 1805 !ssl_add_message_cbb(ssl, cbb.get())) { 1806 return -1; 1807 } 1808 1809 /* The handshake buffer is no longer necessary. */ 1810 SSL_TRANSCRIPT_free_buffer(&hs->transcript); 1811 return 1; 1812 } 1813 1814 static int ssl3_send_next_proto(SSL_HANDSHAKE *hs) { 1815 SSL *const ssl = hs->ssl; 1816 static const uint8_t kZero[32] = {0}; 1817 size_t padding_len = 32 - ((ssl->s3->next_proto_negotiated_len + 2) % 32); 1818 1819 CBB cbb, body, child; 1820 if (!ssl->method->init_message(ssl, &cbb, &body, SSL3_MT_NEXT_PROTO) || 1821 !CBB_add_u8_length_prefixed(&body, &child) || 1822 !CBB_add_bytes(&child, ssl->s3->next_proto_negotiated, 1823 ssl->s3->next_proto_negotiated_len) || 1824 !CBB_add_u8_length_prefixed(&body, &child) || 1825 !CBB_add_bytes(&child, kZero, padding_len) || 1826 !ssl_add_message_cbb(ssl, &cbb)) { 1827 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1828 CBB_cleanup(&cbb); 1829 return -1; 1830 } 1831 1832 return 1; 1833 } 1834 1835 static int ssl3_send_channel_id(SSL_HANDSHAKE *hs) { 1836 SSL *const ssl = hs->ssl; 1837 if (!ssl_do_channel_id_callback(ssl)) { 1838 return -1; 1839 } 1840 1841 if (ssl->tlsext_channel_id_private == NULL) { 1842 ssl->rwstate = SSL_CHANNEL_ID_LOOKUP; 1843 return -1; 1844 } 1845 1846 CBB cbb, body; 1847 if (!ssl->method->init_message(ssl, &cbb, &body, SSL3_MT_CHANNEL_ID) || 1848 !tls1_write_channel_id(hs, &body) || 1849 !ssl_add_message_cbb(ssl, &cbb)) { 1850 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1851 CBB_cleanup(&cbb); 1852 return -1; 1853 } 1854 1855 return 1; 1856 } 1857 1858 static int ssl3_get_new_session_ticket(SSL_HANDSHAKE *hs) { 1859 SSL *const ssl = hs->ssl; 1860 int ret = ssl->method->ssl_get_message(ssl); 1861 if (ret <= 0) { 1862 return ret; 1863 } 1864 1865 if (!ssl_check_message_type(ssl, SSL3_MT_NEW_SESSION_TICKET) || 1866 !ssl_hash_current_message(hs)) { 1867 return -1; 1868 } 1869 1870 CBS new_session_ticket, ticket; 1871 uint32_t tlsext_tick_lifetime_hint; 1872 CBS_init(&new_session_ticket, ssl->init_msg, ssl->init_num); 1873 if (!CBS_get_u32(&new_session_ticket, &tlsext_tick_lifetime_hint) || 1874 !CBS_get_u16_length_prefixed(&new_session_ticket, &ticket) || 1875 CBS_len(&new_session_ticket) != 0) { 1876 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1877 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1878 return -1; 1879 } 1880 1881 if (CBS_len(&ticket) == 0) { 1882 /* RFC 5077 allows a server to change its mind and send no ticket after 1883 * negotiating the extension. The value of |ticket_expected| is checked in 1884 * |ssl_update_cache| so is cleared here to avoid an unnecessary update. */ 1885 hs->ticket_expected = 0; 1886 return 1; 1887 } 1888 1889 int session_renewed = ssl->session != NULL; 1890 SSL_SESSION *session = hs->new_session; 1891 if (session_renewed) { 1892 /* The server is sending a new ticket for an existing session. Sessions are 1893 * immutable once established, so duplicate all but the ticket of the 1894 * existing session. */ 1895 session = SSL_SESSION_dup(ssl->session, SSL_SESSION_INCLUDE_NONAUTH); 1896 if (session == NULL) { 1897 /* This should never happen. */ 1898 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1899 goto err; 1900 } 1901 } 1902 1903 /* |tlsext_tick_lifetime_hint| is measured from when the ticket was issued. */ 1904 ssl_session_rebase_time(ssl, session); 1905 1906 if (!CBS_stow(&ticket, &session->tlsext_tick, &session->tlsext_ticklen)) { 1907 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1908 goto err; 1909 } 1910 session->tlsext_tick_lifetime_hint = tlsext_tick_lifetime_hint; 1911 1912 /* Generate a session ID for this session based on the session ticket. We use 1913 * the session ID mechanism for detecting ticket resumption. This also fits in 1914 * with assumptions elsewhere in OpenSSL.*/ 1915 if (!EVP_Digest(CBS_data(&ticket), CBS_len(&ticket), 1916 session->session_id, &session->session_id_length, 1917 EVP_sha256(), NULL)) { 1918 goto err; 1919 } 1920 1921 if (session_renewed) { 1922 session->not_resumable = 0; 1923 SSL_SESSION_free(ssl->session); 1924 ssl->session = session; 1925 } 1926 1927 return 1; 1928 1929 err: 1930 if (session_renewed) { 1931 SSL_SESSION_free(session); 1932 } 1933 return -1; 1934 } 1935
