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 #include <openssl/ssl.h> 150 151 #include <assert.h> 152 #include <stdio.h> 153 #include <string.h> 154 155 #include <openssl/bn.h> 156 #include <openssl/buf.h> 157 #include <openssl/bytestring.h> 158 #include <openssl/cipher.h> 159 #include <openssl/dh.h> 160 #include <openssl/ec.h> 161 #include <openssl/ecdsa.h> 162 #include <openssl/err.h> 163 #include <openssl/evp.h> 164 #include <openssl/hmac.h> 165 #include <openssl/md5.h> 166 #include <openssl/mem.h> 167 #include <openssl/obj.h> 168 #include <openssl/rand.h> 169 #include <openssl/sha.h> 170 #include <openssl/x509.h> 171 172 #include "internal.h" 173 #include "../crypto/internal.h" 174 #include "../crypto/dh/internal.h" 175 176 177 int ssl3_accept(SSL *ssl) { 178 BUF_MEM *buf = NULL; 179 uint32_t alg_a; 180 void (*cb)(const SSL *ssl, int type, int value) = NULL; 181 int ret = -1; 182 int new_state, state, skip = 0; 183 184 assert(ssl->handshake_func == ssl3_accept); 185 assert(ssl->server); 186 assert(!SSL_IS_DTLS(ssl)); 187 188 ERR_clear_error(); 189 ERR_clear_system_error(); 190 191 if (ssl->info_callback != NULL) { 192 cb = ssl->info_callback; 193 } else if (ssl->ctx->info_callback != NULL) { 194 cb = ssl->ctx->info_callback; 195 } 196 197 ssl->in_handshake++; 198 199 if (ssl->cert == NULL) { 200 OPENSSL_PUT_ERROR(SSL, SSL_R_NO_CERTIFICATE_SET); 201 return -1; 202 } 203 204 for (;;) { 205 state = ssl->state; 206 207 switch (ssl->state) { 208 case SSL_ST_ACCEPT: 209 if (cb != NULL) { 210 cb(ssl, SSL_CB_HANDSHAKE_START, 1); 211 } 212 213 if (ssl->init_buf == NULL) { 214 buf = BUF_MEM_new(); 215 if (!buf || !BUF_MEM_grow(buf, SSL3_RT_MAX_PLAIN_LENGTH)) { 216 ret = -1; 217 goto end; 218 } 219 ssl->init_buf = buf; 220 buf = NULL; 221 } 222 ssl->init_num = 0; 223 224 /* Enable a write buffer. This groups handshake messages within a flight 225 * into a single write. */ 226 if (!ssl_init_wbio_buffer(ssl, 1)) { 227 ret = -1; 228 goto end; 229 } 230 231 if (!ssl3_init_handshake_buffer(ssl)) { 232 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 233 ret = -1; 234 goto end; 235 } 236 237 if (!ssl->s3->have_version) { 238 ssl->state = SSL3_ST_SR_INITIAL_BYTES; 239 } else { 240 ssl->state = SSL3_ST_SR_CLNT_HELLO_A; 241 } 242 break; 243 244 case SSL3_ST_SR_INITIAL_BYTES: 245 ret = ssl3_get_initial_bytes(ssl); 246 if (ret <= 0) { 247 goto end; 248 } 249 /* ssl3_get_initial_bytes sets ssl->state to one of 250 * SSL3_ST_SR_V2_CLIENT_HELLO or SSL3_ST_SR_CLNT_HELLO_A on success. */ 251 break; 252 253 case SSL3_ST_SR_V2_CLIENT_HELLO: 254 ret = ssl3_get_v2_client_hello(ssl); 255 if (ret <= 0) { 256 goto end; 257 } 258 ssl->state = SSL3_ST_SR_CLNT_HELLO_A; 259 break; 260 261 case SSL3_ST_SR_CLNT_HELLO_A: 262 case SSL3_ST_SR_CLNT_HELLO_B: 263 case SSL3_ST_SR_CLNT_HELLO_C: 264 case SSL3_ST_SR_CLNT_HELLO_D: 265 ssl->shutdown = 0; 266 ret = ssl3_get_client_hello(ssl); 267 if (ret <= 0) { 268 goto end; 269 } 270 ssl->state = SSL3_ST_SW_SRVR_HELLO_A; 271 ssl->init_num = 0; 272 break; 273 274 case SSL3_ST_SW_SRVR_HELLO_A: 275 case SSL3_ST_SW_SRVR_HELLO_B: 276 ret = ssl3_send_server_hello(ssl); 277 if (ret <= 0) { 278 goto end; 279 } 280 if (ssl->hit) { 281 if (ssl->tlsext_ticket_expected) { 282 ssl->state = SSL3_ST_SW_SESSION_TICKET_A; 283 } else { 284 ssl->state = SSL3_ST_SW_CHANGE_A; 285 } 286 } else { 287 ssl->state = SSL3_ST_SW_CERT_A; 288 } 289 ssl->init_num = 0; 290 break; 291 292 case SSL3_ST_SW_CERT_A: 293 case SSL3_ST_SW_CERT_B: 294 if (ssl_cipher_has_server_public_key(ssl->s3->tmp.new_cipher)) { 295 ret = ssl3_send_server_certificate(ssl); 296 if (ret <= 0) { 297 goto end; 298 } 299 if (ssl->s3->tmp.certificate_status_expected) { 300 ssl->state = SSL3_ST_SW_CERT_STATUS_A; 301 } else { 302 ssl->state = SSL3_ST_SW_KEY_EXCH_A; 303 } 304 } else { 305 skip = 1; 306 ssl->state = SSL3_ST_SW_KEY_EXCH_A; 307 } 308 ssl->init_num = 0; 309 break; 310 311 case SSL3_ST_SW_CERT_STATUS_A: 312 case SSL3_ST_SW_CERT_STATUS_B: 313 ret = ssl3_send_certificate_status(ssl); 314 if (ret <= 0) { 315 goto end; 316 } 317 ssl->state = SSL3_ST_SW_KEY_EXCH_A; 318 ssl->init_num = 0; 319 break; 320 321 case SSL3_ST_SW_KEY_EXCH_A: 322 case SSL3_ST_SW_KEY_EXCH_B: 323 case SSL3_ST_SW_KEY_EXCH_C: 324 alg_a = ssl->s3->tmp.new_cipher->algorithm_auth; 325 326 /* Send a ServerKeyExchange message if: 327 * - The key exchange is ephemeral or anonymous 328 * Diffie-Hellman. 329 * - There is a PSK identity hint. 330 * 331 * TODO(davidben): This logic is currently duplicated in d1_srvr.c. Fix 332 * this. In the meantime, keep them in sync. */ 333 if (ssl_cipher_requires_server_key_exchange(ssl->s3->tmp.new_cipher) || 334 ((alg_a & SSL_aPSK) && ssl->psk_identity_hint)) { 335 ret = ssl3_send_server_key_exchange(ssl); 336 if (ret <= 0) { 337 goto end; 338 } 339 } else { 340 skip = 1; 341 } 342 343 ssl->state = SSL3_ST_SW_CERT_REQ_A; 344 ssl->init_num = 0; 345 break; 346 347 case SSL3_ST_SW_CERT_REQ_A: 348 case SSL3_ST_SW_CERT_REQ_B: 349 if (ssl->s3->tmp.cert_request) { 350 ret = ssl3_send_certificate_request(ssl); 351 if (ret <= 0) { 352 goto end; 353 } 354 } else { 355 skip = 1; 356 } 357 ssl->state = SSL3_ST_SW_SRVR_DONE_A; 358 ssl->init_num = 0; 359 break; 360 361 case SSL3_ST_SW_SRVR_DONE_A: 362 case SSL3_ST_SW_SRVR_DONE_B: 363 ret = ssl3_send_server_done(ssl); 364 if (ret <= 0) { 365 goto end; 366 } 367 ssl->s3->tmp.next_state = SSL3_ST_SR_CERT_A; 368 ssl->state = SSL3_ST_SW_FLUSH; 369 ssl->init_num = 0; 370 break; 371 372 case SSL3_ST_SW_FLUSH: 373 /* This code originally checked to see if any data was pending using 374 * BIO_CTRL_INFO and then flushed. This caused problems as documented 375 * in PR#1939. The proposed fix doesn't completely resolve this issue 376 * as buggy implementations of BIO_CTRL_PENDING still exist. So instead 377 * we just flush unconditionally. */ 378 ssl->rwstate = SSL_WRITING; 379 if (BIO_flush(ssl->wbio) <= 0) { 380 ret = -1; 381 goto end; 382 } 383 ssl->rwstate = SSL_NOTHING; 384 385 ssl->state = ssl->s3->tmp.next_state; 386 break; 387 388 case SSL3_ST_SR_CERT_A: 389 case SSL3_ST_SR_CERT_B: 390 if (ssl->s3->tmp.cert_request) { 391 ret = ssl3_get_client_certificate(ssl); 392 if (ret <= 0) { 393 goto end; 394 } 395 } 396 ssl->init_num = 0; 397 ssl->state = SSL3_ST_SR_KEY_EXCH_A; 398 break; 399 400 case SSL3_ST_SR_KEY_EXCH_A: 401 case SSL3_ST_SR_KEY_EXCH_B: 402 case SSL3_ST_SR_KEY_EXCH_C: 403 ret = ssl3_get_client_key_exchange(ssl); 404 if (ret <= 0) { 405 goto end; 406 } 407 ssl->state = SSL3_ST_SR_CERT_VRFY_A; 408 ssl->init_num = 0; 409 break; 410 411 case SSL3_ST_SR_CERT_VRFY_A: 412 case SSL3_ST_SR_CERT_VRFY_B: 413 ret = ssl3_get_cert_verify(ssl); 414 if (ret <= 0) { 415 goto end; 416 } 417 418 ssl->state = SSL3_ST_SR_CHANGE; 419 ssl->init_num = 0; 420 break; 421 422 case SSL3_ST_SR_CHANGE: 423 ret = ssl->method->ssl_read_change_cipher_spec(ssl); 424 if (ret <= 0) { 425 goto end; 426 } 427 428 if (!ssl3_do_change_cipher_spec(ssl)) { 429 ret = -1; 430 goto end; 431 } 432 433 if (ssl->s3->next_proto_neg_seen) { 434 ssl->state = SSL3_ST_SR_NEXT_PROTO_A; 435 } else if (ssl->s3->tlsext_channel_id_valid) { 436 ssl->state = SSL3_ST_SR_CHANNEL_ID_A; 437 } else { 438 ssl->state = SSL3_ST_SR_FINISHED_A; 439 } 440 break; 441 442 case SSL3_ST_SR_NEXT_PROTO_A: 443 case SSL3_ST_SR_NEXT_PROTO_B: 444 ret = ssl3_get_next_proto(ssl); 445 if (ret <= 0) { 446 goto end; 447 } 448 ssl->init_num = 0; 449 if (ssl->s3->tlsext_channel_id_valid) { 450 ssl->state = SSL3_ST_SR_CHANNEL_ID_A; 451 } else { 452 ssl->state = SSL3_ST_SR_FINISHED_A; 453 } 454 break; 455 456 case SSL3_ST_SR_CHANNEL_ID_A: 457 case SSL3_ST_SR_CHANNEL_ID_B: 458 ret = ssl3_get_channel_id(ssl); 459 if (ret <= 0) { 460 goto end; 461 } 462 ssl->init_num = 0; 463 ssl->state = SSL3_ST_SR_FINISHED_A; 464 break; 465 466 case SSL3_ST_SR_FINISHED_A: 467 case SSL3_ST_SR_FINISHED_B: 468 ret = ssl3_get_finished(ssl, SSL3_ST_SR_FINISHED_A, 469 SSL3_ST_SR_FINISHED_B); 470 if (ret <= 0) { 471 goto end; 472 } 473 474 if (ssl->hit) { 475 ssl->state = SSL_ST_OK; 476 } else if (ssl->tlsext_ticket_expected) { 477 ssl->state = SSL3_ST_SW_SESSION_TICKET_A; 478 } else { 479 ssl->state = SSL3_ST_SW_CHANGE_A; 480 } 481 /* If this is a full handshake with ChannelID then record the hashshake 482 * hashes in |ssl->session| in case we need them to verify a ChannelID 483 * signature on a resumption of this session in the future. */ 484 if (!ssl->hit && ssl->s3->tlsext_channel_id_valid) { 485 ret = tls1_record_handshake_hashes_for_channel_id(ssl); 486 if (ret <= 0) { 487 goto end; 488 } 489 } 490 ssl->init_num = 0; 491 break; 492 493 case SSL3_ST_SW_SESSION_TICKET_A: 494 case SSL3_ST_SW_SESSION_TICKET_B: 495 ret = ssl3_send_new_session_ticket(ssl); 496 if (ret <= 0) { 497 goto end; 498 } 499 ssl->state = SSL3_ST_SW_CHANGE_A; 500 ssl->init_num = 0; 501 break; 502 503 case SSL3_ST_SW_CHANGE_A: 504 case SSL3_ST_SW_CHANGE_B: 505 ssl->session->cipher = ssl->s3->tmp.new_cipher; 506 if (!ssl->enc_method->setup_key_block(ssl)) { 507 ret = -1; 508 goto end; 509 } 510 511 ret = ssl3_send_change_cipher_spec(ssl, SSL3_ST_SW_CHANGE_A, 512 SSL3_ST_SW_CHANGE_B); 513 if (ret <= 0) { 514 goto end; 515 } 516 ssl->state = SSL3_ST_SW_FINISHED_A; 517 ssl->init_num = 0; 518 519 if (!ssl->enc_method->change_cipher_state( 520 ssl, SSL3_CHANGE_CIPHER_SERVER_WRITE)) { 521 ret = -1; 522 goto end; 523 } 524 break; 525 526 case SSL3_ST_SW_FINISHED_A: 527 case SSL3_ST_SW_FINISHED_B: 528 ret = ssl3_send_finished(ssl, SSL3_ST_SW_FINISHED_A, 529 SSL3_ST_SW_FINISHED_B, 530 ssl->enc_method->server_finished_label, 531 ssl->enc_method->server_finished_label_len); 532 if (ret <= 0) { 533 goto end; 534 } 535 ssl->state = SSL3_ST_SW_FLUSH; 536 if (ssl->hit) { 537 ssl->s3->tmp.next_state = SSL3_ST_SR_CHANGE; 538 } else { 539 ssl->s3->tmp.next_state = SSL_ST_OK; 540 } 541 ssl->init_num = 0; 542 break; 543 544 case SSL_ST_OK: 545 /* clean a few things up */ 546 ssl3_cleanup_key_block(ssl); 547 548 BUF_MEM_free(ssl->init_buf); 549 ssl->init_buf = NULL; 550 551 /* remove buffering on output */ 552 ssl_free_wbio_buffer(ssl); 553 554 ssl->init_num = 0; 555 556 /* If we aren't retaining peer certificates then we can discard it 557 * now. */ 558 if (ssl->ctx->retain_only_sha256_of_client_certs) { 559 X509_free(ssl->session->peer); 560 ssl->session->peer = NULL; 561 sk_X509_pop_free(ssl->session->cert_chain, X509_free); 562 ssl->session->cert_chain = NULL; 563 } 564 565 ssl->s3->initial_handshake_complete = 1; 566 567 ssl_update_cache(ssl, SSL_SESS_CACHE_SERVER); 568 569 if (cb != NULL) { 570 cb(ssl, SSL_CB_HANDSHAKE_DONE, 1); 571 } 572 573 ret = 1; 574 goto end; 575 576 default: 577 OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_STATE); 578 ret = -1; 579 goto end; 580 } 581 582 if (!ssl->s3->tmp.reuse_message && !skip && cb != NULL && 583 ssl->state != state) { 584 new_state = ssl->state; 585 ssl->state = state; 586 cb(ssl, SSL_CB_ACCEPT_LOOP, 1); 587 ssl->state = new_state; 588 } 589 skip = 0; 590 } 591 592 end: 593 ssl->in_handshake--; 594 BUF_MEM_free(buf); 595 if (cb != NULL) { 596 cb(ssl, SSL_CB_ACCEPT_EXIT, ret); 597 } 598 return ret; 599 } 600 601 int ssl3_get_initial_bytes(SSL *ssl) { 602 /* Read the first 5 bytes, the size of the TLS record header. This is 603 * sufficient to detect a V2ClientHello and ensures that we never read beyond 604 * the first record. */ 605 int ret = ssl_read_buffer_extend_to(ssl, SSL3_RT_HEADER_LENGTH); 606 if (ret <= 0) { 607 return ret; 608 } 609 assert(ssl_read_buffer_len(ssl) == SSL3_RT_HEADER_LENGTH); 610 const uint8_t *p = ssl_read_buffer(ssl); 611 612 /* Some dedicated error codes for protocol mixups should the application wish 613 * to interpret them differently. (These do not overlap with ClientHello or 614 * V2ClientHello.) */ 615 if (strncmp("GET ", (const char *)p, 4) == 0 || 616 strncmp("POST ", (const char *)p, 5) == 0 || 617 strncmp("HEAD ", (const char *)p, 5) == 0 || 618 strncmp("PUT ", (const char *)p, 4) == 0) { 619 OPENSSL_PUT_ERROR(SSL, SSL_R_HTTP_REQUEST); 620 return -1; 621 } 622 if (strncmp("CONNE", (const char *)p, 5) == 0) { 623 OPENSSL_PUT_ERROR(SSL, SSL_R_HTTPS_PROXY_REQUEST); 624 return -1; 625 } 626 627 /* Determine if this is a V2ClientHello. */ 628 if ((p[0] & 0x80) && p[2] == SSL2_MT_CLIENT_HELLO && 629 p[3] >= SSL3_VERSION_MAJOR) { 630 /* This is a V2ClientHello. */ 631 ssl->state = SSL3_ST_SR_V2_CLIENT_HELLO; 632 return 1; 633 } 634 635 /* Fall through to the standard logic. */ 636 ssl->state = SSL3_ST_SR_CLNT_HELLO_A; 637 return 1; 638 } 639 640 int ssl3_get_v2_client_hello(SSL *ssl) { 641 const uint8_t *p; 642 int ret; 643 CBS v2_client_hello, cipher_specs, session_id, challenge; 644 size_t msg_length, rand_len, len; 645 uint8_t msg_type; 646 uint16_t version, cipher_spec_length, session_id_length, challenge_length; 647 CBB client_hello, hello_body, cipher_suites; 648 uint8_t random[SSL3_RANDOM_SIZE]; 649 650 /* Determine the length of the V2ClientHello. */ 651 assert(ssl_read_buffer_len(ssl) >= SSL3_RT_HEADER_LENGTH); 652 p = ssl_read_buffer(ssl); 653 msg_length = ((p[0] & 0x7f) << 8) | p[1]; 654 if (msg_length > (1024 * 4)) { 655 OPENSSL_PUT_ERROR(SSL, SSL_R_RECORD_TOO_LARGE); 656 return -1; 657 } 658 if (msg_length < SSL3_RT_HEADER_LENGTH - 2) { 659 /* Reject lengths that are too short early. We have already read 660 * |SSL3_RT_HEADER_LENGTH| bytes, so we should not attempt to process an 661 * (invalid) V2ClientHello which would be shorter than that. */ 662 OPENSSL_PUT_ERROR(SSL, SSL_R_RECORD_LENGTH_MISMATCH); 663 return -1; 664 } 665 666 /* Read the remainder of the V2ClientHello. */ 667 ret = ssl_read_buffer_extend_to(ssl, 2 + msg_length); 668 if (ret <= 0) { 669 return ret; 670 } 671 assert(ssl_read_buffer_len(ssl) == msg_length + 2); 672 CBS_init(&v2_client_hello, ssl_read_buffer(ssl) + 2, msg_length); 673 674 /* The V2ClientHello without the length is incorporated into the handshake 675 * hash. */ 676 if (!ssl3_update_handshake_hash(ssl, CBS_data(&v2_client_hello), 677 CBS_len(&v2_client_hello))) { 678 return -1; 679 } 680 if (ssl->msg_callback) { 681 ssl->msg_callback(0, SSL2_VERSION, 0, CBS_data(&v2_client_hello), 682 CBS_len(&v2_client_hello), ssl, ssl->msg_callback_arg); 683 } 684 685 if (!CBS_get_u8(&v2_client_hello, &msg_type) || 686 !CBS_get_u16(&v2_client_hello, &version) || 687 !CBS_get_u16(&v2_client_hello, &cipher_spec_length) || 688 !CBS_get_u16(&v2_client_hello, &session_id_length) || 689 !CBS_get_u16(&v2_client_hello, &challenge_length) || 690 !CBS_get_bytes(&v2_client_hello, &cipher_specs, cipher_spec_length) || 691 !CBS_get_bytes(&v2_client_hello, &session_id, session_id_length) || 692 !CBS_get_bytes(&v2_client_hello, &challenge, challenge_length) || 693 CBS_len(&v2_client_hello) != 0) { 694 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 695 return -1; 696 } 697 698 /* msg_type has already been checked. */ 699 assert(msg_type == SSL2_MT_CLIENT_HELLO); 700 701 /* The client_random is the V2ClientHello challenge. Truncate or 702 * left-pad with zeros as needed. */ 703 memset(random, 0, SSL3_RANDOM_SIZE); 704 rand_len = CBS_len(&challenge); 705 if (rand_len > SSL3_RANDOM_SIZE) { 706 rand_len = SSL3_RANDOM_SIZE; 707 } 708 memcpy(random + (SSL3_RANDOM_SIZE - rand_len), CBS_data(&challenge), 709 rand_len); 710 711 /* Write out an equivalent SSLv3 ClientHello. */ 712 CBB_zero(&client_hello); 713 if (!CBB_init_fixed(&client_hello, (uint8_t *)ssl->init_buf->data, 714 ssl->init_buf->max) || 715 !CBB_add_u8(&client_hello, SSL3_MT_CLIENT_HELLO) || 716 !CBB_add_u24_length_prefixed(&client_hello, &hello_body) || 717 !CBB_add_u16(&hello_body, version) || 718 !CBB_add_bytes(&hello_body, random, SSL3_RANDOM_SIZE) || 719 /* No session id. */ 720 !CBB_add_u8(&hello_body, 0) || 721 !CBB_add_u16_length_prefixed(&hello_body, &cipher_suites)) { 722 CBB_cleanup(&client_hello); 723 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 724 return -1; 725 } 726 727 /* Copy the cipher suites. */ 728 while (CBS_len(&cipher_specs) > 0) { 729 uint32_t cipher_spec; 730 if (!CBS_get_u24(&cipher_specs, &cipher_spec)) { 731 CBB_cleanup(&client_hello); 732 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 733 return -1; 734 } 735 736 /* Skip SSLv2 ciphers. */ 737 if ((cipher_spec & 0xff0000) != 0) { 738 continue; 739 } 740 if (!CBB_add_u16(&cipher_suites, cipher_spec)) { 741 CBB_cleanup(&client_hello); 742 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 743 return -1; 744 } 745 } 746 747 /* Add the null compression scheme and finish. */ 748 if (!CBB_add_u8(&hello_body, 1) || !CBB_add_u8(&hello_body, 0) || 749 !CBB_finish(&client_hello, NULL, &len)) { 750 CBB_cleanup(&client_hello); 751 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 752 return -1; 753 } 754 755 /* Mark the message for "re"-use by the version-specific method. */ 756 ssl->s3->tmp.reuse_message = 1; 757 ssl->s3->tmp.message_type = SSL3_MT_CLIENT_HELLO; 758 /* The handshake message header is 4 bytes. */ 759 ssl->s3->tmp.message_size = len - 4; 760 761 /* Consume and discard the V2ClientHello. */ 762 ssl_read_buffer_consume(ssl, 2 + msg_length); 763 ssl_read_buffer_discard(ssl); 764 765 return 1; 766 } 767 768 int ssl3_get_client_hello(SSL *ssl) { 769 int ok, al = SSL_AD_INTERNAL_ERROR, ret = -1; 770 long n; 771 const SSL_CIPHER *c; 772 STACK_OF(SSL_CIPHER) *ciphers = NULL; 773 struct ssl_early_callback_ctx early_ctx; 774 CBS client_hello; 775 uint16_t client_version; 776 CBS client_random, session_id, cipher_suites, compression_methods; 777 SSL_SESSION *session = NULL; 778 779 /* We do this so that we will respond with our native type. If we are TLSv1 780 * and we get SSLv3, we will respond with TLSv1, This down switching should 781 * be handled by a different method. If we are SSLv3, we will respond with 782 * SSLv3, even if prompted with TLSv1. */ 783 switch (ssl->state) { 784 case SSL3_ST_SR_CLNT_HELLO_A: 785 case SSL3_ST_SR_CLNT_HELLO_B: 786 n = ssl->method->ssl_get_message( 787 ssl, SSL3_ST_SR_CLNT_HELLO_A, SSL3_ST_SR_CLNT_HELLO_B, 788 SSL3_MT_CLIENT_HELLO, SSL3_RT_MAX_PLAIN_LENGTH, 789 ssl_hash_message, &ok); 790 791 if (!ok) { 792 return n; 793 } 794 795 ssl->state = SSL3_ST_SR_CLNT_HELLO_C; 796 /* fallthrough */ 797 case SSL3_ST_SR_CLNT_HELLO_C: 798 case SSL3_ST_SR_CLNT_HELLO_D: 799 /* We have previously parsed the ClientHello message, and can't call 800 * ssl_get_message again without hashing the message into the Finished 801 * digest again. */ 802 n = ssl->init_num; 803 804 memset(&early_ctx, 0, sizeof(early_ctx)); 805 early_ctx.ssl = ssl; 806 early_ctx.client_hello = ssl->init_msg; 807 early_ctx.client_hello_len = n; 808 if (!ssl_early_callback_init(&early_ctx)) { 809 al = SSL_AD_DECODE_ERROR; 810 OPENSSL_PUT_ERROR(SSL, SSL_R_CLIENTHELLO_PARSE_FAILED); 811 goto f_err; 812 } 813 814 if (ssl->state == SSL3_ST_SR_CLNT_HELLO_C && 815 ssl->ctx->select_certificate_cb != NULL) { 816 ssl->state = SSL3_ST_SR_CLNT_HELLO_D; 817 switch (ssl->ctx->select_certificate_cb(&early_ctx)) { 818 case 0: 819 ssl->rwstate = SSL_CERTIFICATE_SELECTION_PENDING; 820 goto err; 821 822 case -1: 823 /* Connection rejected. */ 824 al = SSL_AD_ACCESS_DENIED; 825 OPENSSL_PUT_ERROR(SSL, SSL_R_CONNECTION_REJECTED); 826 goto f_err; 827 828 default: 829 /* fallthrough */; 830 } 831 } 832 ssl->state = SSL3_ST_SR_CLNT_HELLO_D; 833 break; 834 835 default: 836 OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_STATE); 837 return -1; 838 } 839 840 CBS_init(&client_hello, ssl->init_msg, n); 841 if (!CBS_get_u16(&client_hello, &client_version) || 842 !CBS_get_bytes(&client_hello, &client_random, SSL3_RANDOM_SIZE) || 843 !CBS_get_u8_length_prefixed(&client_hello, &session_id) || 844 CBS_len(&session_id) > SSL_MAX_SSL_SESSION_ID_LENGTH) { 845 al = SSL_AD_DECODE_ERROR; 846 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 847 goto f_err; 848 } 849 850 /* use version from inside client hello, not from record header (may differ: 851 * see RFC 2246, Appendix E, second paragraph) */ 852 ssl->client_version = client_version; 853 854 /* Load the client random. */ 855 memcpy(ssl->s3->client_random, CBS_data(&client_random), SSL3_RANDOM_SIZE); 856 857 if (SSL_IS_DTLS(ssl)) { 858 CBS cookie; 859 860 if (!CBS_get_u8_length_prefixed(&client_hello, &cookie) || 861 CBS_len(&cookie) > DTLS1_COOKIE_LENGTH) { 862 al = SSL_AD_DECODE_ERROR; 863 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 864 goto f_err; 865 } 866 } 867 868 /* Note: This codepath may run twice if |ssl_get_prev_session| completes 869 * asynchronously. 870 * 871 * TODO(davidben): Clean up the order of events around ClientHello 872 * processing. */ 873 if (!ssl->s3->have_version) { 874 /* Select version to use */ 875 uint16_t version = ssl3_get_mutual_version(ssl, client_version); 876 if (version == 0) { 877 OPENSSL_PUT_ERROR(SSL, SSL_R_UNSUPPORTED_PROTOCOL); 878 ssl->version = ssl->client_version; 879 al = SSL_AD_PROTOCOL_VERSION; 880 goto f_err; 881 } 882 ssl->version = version; 883 ssl->enc_method = ssl3_get_enc_method(version); 884 assert(ssl->enc_method != NULL); 885 /* At this point, the connection's version is known and |ssl->version| is 886 * fixed. Begin enforcing the record-layer version. */ 887 ssl->s3->have_version = 1; 888 } else if (SSL_IS_DTLS(ssl) ? (ssl->client_version > ssl->version) 889 : (ssl->client_version < ssl->version)) { 890 OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_VERSION_NUMBER); 891 al = SSL_AD_PROTOCOL_VERSION; 892 goto f_err; 893 } 894 895 ssl->hit = 0; 896 int send_new_ticket = 0; 897 switch (ssl_get_prev_session(ssl, &session, &send_new_ticket, &early_ctx)) { 898 case ssl_session_success: 899 break; 900 case ssl_session_error: 901 goto err; 902 case ssl_session_retry: 903 ssl->rwstate = SSL_PENDING_SESSION; 904 goto err; 905 } 906 ssl->tlsext_ticket_expected = send_new_ticket; 907 908 /* The EMS state is needed when making the resumption decision, but 909 * extensions are not normally parsed until later. This detects the EMS 910 * extension for the resumption decision and it's checked against the result 911 * of the normal parse later in this function. */ 912 const uint8_t *ems_data; 913 size_t ems_len; 914 int have_extended_master_secret = 915 ssl->version != SSL3_VERSION && 916 SSL_early_callback_ctx_extension_get(&early_ctx, 917 TLSEXT_TYPE_extended_master_secret, 918 &ems_data, &ems_len) && 919 ems_len == 0; 920 921 if (session != NULL) { 922 if (session->extended_master_secret && 923 !have_extended_master_secret) { 924 /* A ClientHello without EMS that attempts to resume a session with EMS 925 * is fatal to the connection. */ 926 al = SSL_AD_HANDSHAKE_FAILURE; 927 OPENSSL_PUT_ERROR(SSL, SSL_R_RESUMED_EMS_SESSION_WITHOUT_EMS_EXTENSION); 928 goto f_err; 929 } 930 931 ssl->hit = 932 /* Only resume if the session's version matches the negotiated version: 933 * most clients do not accept a mismatch. */ 934 ssl->version == session->ssl_version && 935 /* If the client offers the EMS extension, but the previous session 936 * didn't use it, then negotiate a new session. */ 937 have_extended_master_secret == session->extended_master_secret; 938 } 939 940 if (ssl->hit) { 941 /* Use the new session. */ 942 SSL_SESSION_free(ssl->session); 943 ssl->session = session; 944 session = NULL; 945 946 ssl->verify_result = ssl->session->verify_result; 947 } else { 948 if (!ssl_get_new_session(ssl, 1 /* server */)) { 949 goto err; 950 } 951 952 /* Clear the session ID if we want the session to be single-use. */ 953 if (!(ssl->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER)) { 954 ssl->session->session_id_length = 0; 955 } 956 } 957 958 if (ssl->ctx->dos_protection_cb != NULL && 959 ssl->ctx->dos_protection_cb(&early_ctx) == 0) { 960 /* Connection rejected for DOS reasons. */ 961 al = SSL_AD_ACCESS_DENIED; 962 OPENSSL_PUT_ERROR(SSL, SSL_R_CONNECTION_REJECTED); 963 goto f_err; 964 } 965 966 if (!CBS_get_u16_length_prefixed(&client_hello, &cipher_suites) || 967 CBS_len(&cipher_suites) == 0 || 968 CBS_len(&cipher_suites) % 2 != 0 || 969 !CBS_get_u8_length_prefixed(&client_hello, &compression_methods) || 970 CBS_len(&compression_methods) == 0) { 971 al = SSL_AD_DECODE_ERROR; 972 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 973 goto f_err; 974 } 975 976 ciphers = ssl_bytes_to_cipher_list(ssl, &cipher_suites); 977 if (ciphers == NULL) { 978 goto err; 979 } 980 981 /* If it is a hit, check that the cipher is in the list. */ 982 if (ssl->hit) { 983 size_t j; 984 int found_cipher = 0; 985 uint32_t id = ssl->session->cipher->id; 986 987 for (j = 0; j < sk_SSL_CIPHER_num(ciphers); j++) { 988 c = sk_SSL_CIPHER_value(ciphers, j); 989 if (c->id == id) { 990 found_cipher = 1; 991 break; 992 } 993 } 994 995 if (!found_cipher) { 996 /* we need to have the cipher in the cipher list if we are asked to reuse 997 * it */ 998 al = SSL_AD_ILLEGAL_PARAMETER; 999 OPENSSL_PUT_ERROR(SSL, SSL_R_REQUIRED_CIPHER_MISSING); 1000 goto f_err; 1001 } 1002 } 1003 1004 /* Only null compression is supported. */ 1005 if (memchr(CBS_data(&compression_methods), 0, 1006 CBS_len(&compression_methods)) == NULL) { 1007 al = SSL_AD_ILLEGAL_PARAMETER; 1008 OPENSSL_PUT_ERROR(SSL, SSL_R_NO_COMPRESSION_SPECIFIED); 1009 goto f_err; 1010 } 1011 1012 /* TLS extensions. */ 1013 if (ssl->version >= SSL3_VERSION && 1014 !ssl_parse_clienthello_tlsext(ssl, &client_hello)) { 1015 OPENSSL_PUT_ERROR(SSL, SSL_R_PARSE_TLSEXT); 1016 goto err; 1017 } 1018 1019 /* There should be nothing left over in the record. */ 1020 if (CBS_len(&client_hello) != 0) { 1021 /* wrong packet length */ 1022 al = SSL_AD_DECODE_ERROR; 1023 OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_PACKET_LENGTH); 1024 goto f_err; 1025 } 1026 1027 if (have_extended_master_secret != ssl->s3->tmp.extended_master_secret) { 1028 al = SSL_AD_INTERNAL_ERROR; 1029 OPENSSL_PUT_ERROR(SSL, SSL_R_EMS_STATE_INCONSISTENT); 1030 goto f_err; 1031 } 1032 1033 /* Given ciphers and SSL_get_ciphers, we must pick a cipher */ 1034 if (!ssl->hit) { 1035 if (ciphers == NULL) { 1036 al = SSL_AD_ILLEGAL_PARAMETER; 1037 OPENSSL_PUT_ERROR(SSL, SSL_R_NO_CIPHERS_PASSED); 1038 goto f_err; 1039 } 1040 1041 /* Let cert callback update server certificates if required */ 1042 if (ssl->cert->cert_cb) { 1043 int rv = ssl->cert->cert_cb(ssl, ssl->cert->cert_cb_arg); 1044 if (rv == 0) { 1045 al = SSL_AD_INTERNAL_ERROR; 1046 OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_CB_ERROR); 1047 goto f_err; 1048 } 1049 if (rv < 0) { 1050 ssl->rwstate = SSL_X509_LOOKUP; 1051 goto err; 1052 } 1053 ssl->rwstate = SSL_NOTHING; 1054 } 1055 c = ssl3_choose_cipher(ssl, ciphers, ssl_get_cipher_preferences(ssl)); 1056 1057 if (c == NULL) { 1058 al = SSL_AD_HANDSHAKE_FAILURE; 1059 OPENSSL_PUT_ERROR(SSL, SSL_R_NO_SHARED_CIPHER); 1060 goto f_err; 1061 } 1062 ssl->s3->tmp.new_cipher = c; 1063 1064 /* Determine whether to request a client certificate. */ 1065 ssl->s3->tmp.cert_request = !!(ssl->verify_mode & SSL_VERIFY_PEER); 1066 /* Only request a certificate if Channel ID isn't negotiated. */ 1067 if ((ssl->verify_mode & SSL_VERIFY_PEER_IF_NO_OBC) && 1068 ssl->s3->tlsext_channel_id_valid) { 1069 ssl->s3->tmp.cert_request = 0; 1070 } 1071 /* Plain PSK forbids Certificate and CertificateRequest. */ 1072 if (ssl->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK) { 1073 ssl->s3->tmp.cert_request = 0; 1074 } 1075 } else { 1076 /* Session-id reuse */ 1077 ssl->s3->tmp.new_cipher = ssl->session->cipher; 1078 ssl->s3->tmp.cert_request = 0; 1079 } 1080 1081 /* Now that the cipher is known, initialize the handshake hash. */ 1082 if (!ssl3_init_handshake_hash(ssl)) { 1083 goto f_err; 1084 } 1085 1086 /* In TLS 1.2, client authentication requires hashing the handshake transcript 1087 * under a different hash. Otherwise, release the handshake buffer. */ 1088 if (!SSL_USE_SIGALGS(ssl) || !ssl->s3->tmp.cert_request) { 1089 ssl3_free_handshake_buffer(ssl); 1090 } 1091 1092 /* we now have the following setup; 1093 * client_random 1094 * cipher_list - our prefered list of ciphers 1095 * ciphers - the clients prefered list of ciphers 1096 * compression - basically ignored right now 1097 * ssl version is set - sslv3 1098 * ssl->session - The ssl session has been setup. 1099 * ssl->hit - session reuse flag 1100 * ssl->tmp.new_cipher - the new cipher to use. */ 1101 1102 ret = 1; 1103 1104 if (0) { 1105 f_err: 1106 ssl3_send_alert(ssl, SSL3_AL_FATAL, al); 1107 } 1108 1109 err: 1110 sk_SSL_CIPHER_free(ciphers); 1111 SSL_SESSION_free(session); 1112 return ret; 1113 } 1114 1115 int ssl3_send_server_hello(SSL *ssl) { 1116 if (ssl->state == SSL3_ST_SW_SRVR_HELLO_B) { 1117 return ssl_do_write(ssl); 1118 } 1119 1120 assert(ssl->state == SSL3_ST_SW_SRVR_HELLO_A); 1121 1122 /* We only accept ChannelIDs on connections with ECDHE in order to avoid a 1123 * known attack while we fix ChannelID itself. */ 1124 if (ssl->s3->tlsext_channel_id_valid && 1125 (ssl->s3->tmp.new_cipher->algorithm_mkey & SSL_kECDHE) == 0) { 1126 ssl->s3->tlsext_channel_id_valid = 0; 1127 } 1128 1129 /* If this is a resumption and the original handshake didn't support 1130 * ChannelID then we didn't record the original handshake hashes in the 1131 * session and so cannot resume with ChannelIDs. */ 1132 if (ssl->hit && ssl->session->original_handshake_hash_len == 0) { 1133 ssl->s3->tlsext_channel_id_valid = 0; 1134 } 1135 1136 if (!ssl_fill_hello_random(ssl->s3->server_random, SSL3_RANDOM_SIZE, 1137 1 /* server */)) { 1138 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1139 return -1; 1140 } 1141 1142 CBB cbb, session_id; 1143 size_t length; 1144 CBB_zero(&cbb); 1145 if (!CBB_init_fixed(&cbb, ssl_handshake_start(ssl), 1146 ssl->init_buf->max - SSL_HM_HEADER_LENGTH(ssl)) || 1147 !CBB_add_u16(&cbb, ssl->version) || 1148 !CBB_add_bytes(&cbb, ssl->s3->server_random, SSL3_RANDOM_SIZE) || 1149 !CBB_add_u8_length_prefixed(&cbb, &session_id) || 1150 !CBB_add_bytes(&session_id, ssl->session->session_id, 1151 ssl->session->session_id_length) || 1152 !CBB_add_u16(&cbb, ssl_cipher_get_value(ssl->s3->tmp.new_cipher)) || 1153 !CBB_add_u8(&cbb, 0 /* no compression */) || 1154 !ssl_add_serverhello_tlsext(ssl, &cbb) || 1155 !CBB_finish(&cbb, NULL, &length) || 1156 !ssl_set_handshake_header(ssl, SSL3_MT_SERVER_HELLO, length)) { 1157 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1158 CBB_cleanup(&cbb); 1159 return -1; 1160 } 1161 1162 ssl->state = SSL3_ST_SW_SRVR_HELLO_B; 1163 return ssl_do_write(ssl); 1164 } 1165 1166 int ssl3_send_certificate_status(SSL *ssl) { 1167 if (ssl->state == SSL3_ST_SW_CERT_STATUS_A) { 1168 CBB out, ocsp_response; 1169 size_t length; 1170 1171 CBB_zero(&out); 1172 if (!CBB_init_fixed(&out, ssl_handshake_start(ssl), 1173 ssl->init_buf->max - SSL_HM_HEADER_LENGTH(ssl)) || 1174 !CBB_add_u8(&out, TLSEXT_STATUSTYPE_ocsp) || 1175 !CBB_add_u24_length_prefixed(&out, &ocsp_response) || 1176 !CBB_add_bytes(&ocsp_response, ssl->ctx->ocsp_response, 1177 ssl->ctx->ocsp_response_length) || 1178 !CBB_finish(&out, NULL, &length) || 1179 !ssl_set_handshake_header(ssl, SSL3_MT_CERTIFICATE_STATUS, length)) { 1180 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1181 CBB_cleanup(&out); 1182 return -1; 1183 } 1184 1185 ssl->state = SSL3_ST_SW_CERT_STATUS_B; 1186 } 1187 1188 /* SSL3_ST_SW_CERT_STATUS_B */ 1189 return ssl_do_write(ssl); 1190 } 1191 1192 int ssl3_send_server_done(SSL *ssl) { 1193 if (ssl->state == SSL3_ST_SW_SRVR_DONE_A) { 1194 if (!ssl_set_handshake_header(ssl, SSL3_MT_SERVER_DONE, 0)) { 1195 return -1; 1196 } 1197 ssl->state = SSL3_ST_SW_SRVR_DONE_B; 1198 } 1199 1200 /* SSL3_ST_SW_SRVR_DONE_B */ 1201 return ssl_do_write(ssl); 1202 } 1203 1204 int ssl3_send_server_key_exchange(SSL *ssl) { 1205 if (ssl->state == SSL3_ST_SW_KEY_EXCH_C) { 1206 return ssl_do_write(ssl); 1207 } 1208 1209 CBB cbb, child; 1210 if (!CBB_init_fixed(&cbb, ssl_handshake_start(ssl), 1211 ssl->init_buf->max - SSL_HM_HEADER_LENGTH(ssl))) { 1212 goto err; 1213 } 1214 1215 if (ssl->state == SSL3_ST_SW_KEY_EXCH_A) { 1216 /* This is the first iteration, so write parameters. */ 1217 uint32_t alg_k = ssl->s3->tmp.new_cipher->algorithm_mkey; 1218 uint32_t alg_a = ssl->s3->tmp.new_cipher->algorithm_auth; 1219 1220 /* PSK ciphers begin with an identity hint. */ 1221 if (alg_a & SSL_aPSK) { 1222 size_t len = 1223 (ssl->psk_identity_hint == NULL) ? 0 : strlen(ssl->psk_identity_hint); 1224 if (!CBB_add_u16_length_prefixed(&cbb, &child) || 1225 !CBB_add_bytes(&child, (const uint8_t *)ssl->psk_identity_hint, 1226 len)) { 1227 goto err; 1228 } 1229 } 1230 1231 if (alg_k & SSL_kDHE) { 1232 /* Determine the group to use. */ 1233 DH *params = ssl->cert->dh_tmp; 1234 if (params == NULL && ssl->cert->dh_tmp_cb != NULL) { 1235 params = ssl->cert->dh_tmp_cb(ssl, 0, 1024); 1236 } 1237 if (params == NULL) { 1238 OPENSSL_PUT_ERROR(SSL, SSL_R_MISSING_TMP_DH_KEY); 1239 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); 1240 goto err; 1241 } 1242 ssl->session->key_exchange_info = DH_num_bits(params); 1243 1244 /* Set up DH, generate a key, and emit the public half. */ 1245 DH *dh = DHparams_dup(params); 1246 if (dh == NULL) { 1247 goto err; 1248 } 1249 1250 SSL_ECDH_CTX_init_for_dhe(&ssl->s3->tmp.ecdh_ctx, dh); 1251 if (!CBB_add_u16_length_prefixed(&cbb, &child) || 1252 !BN_bn2cbb_padded(&child, BN_num_bytes(params->p), params->p) || 1253 !CBB_add_u16_length_prefixed(&cbb, &child) || 1254 !BN_bn2cbb_padded(&child, BN_num_bytes(params->g), params->g) || 1255 !CBB_add_u16_length_prefixed(&cbb, &child) || 1256 !SSL_ECDH_CTX_generate_keypair(&ssl->s3->tmp.ecdh_ctx, &child)) { 1257 goto err; 1258 } 1259 } else if (alg_k & SSL_kECDHE) { 1260 /* Determine the curve to use. */ 1261 uint16_t curve_id; 1262 if (!tls1_get_shared_curve(ssl, &curve_id)) { 1263 OPENSSL_PUT_ERROR(SSL, SSL_R_MISSING_TMP_ECDH_KEY); 1264 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); 1265 goto err; 1266 } 1267 ssl->session->key_exchange_info = curve_id; 1268 1269 /* Set up ECDH, generate a key, and emit the public half. */ 1270 if (!SSL_ECDH_CTX_init(&ssl->s3->tmp.ecdh_ctx, curve_id) || 1271 !CBB_add_u8(&cbb, NAMED_CURVE_TYPE) || 1272 !CBB_add_u16(&cbb, curve_id) || 1273 !CBB_add_u8_length_prefixed(&cbb, &child) || 1274 !SSL_ECDH_CTX_generate_keypair(&ssl->s3->tmp.ecdh_ctx, &child)) { 1275 goto err; 1276 } 1277 } else { 1278 assert(alg_k & SSL_kPSK); 1279 } 1280 1281 /* Otherwise, restore |cbb| from the previous iteration. 1282 * TODO(davidben): When |ssl->init_buf| is gone, come up with a simpler 1283 * pattern. Probably keep the |CBB| around in the handshake state. */ 1284 } else if (!CBB_did_write(&cbb, ssl->init_num - SSL_HM_HEADER_LENGTH(ssl))) { 1285 goto err; 1286 } 1287 1288 /* Add a signature. */ 1289 if (ssl_cipher_has_server_public_key(ssl->s3->tmp.new_cipher)) { 1290 if (!ssl_has_private_key(ssl)) { 1291 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); 1292 goto err; 1293 } 1294 1295 const size_t max_sig_len = ssl_private_key_max_signature_len(ssl); 1296 size_t sig_len; 1297 enum ssl_private_key_result_t sign_result; 1298 if (ssl->state == SSL3_ST_SW_KEY_EXCH_A) { 1299 /* This is the first iteration, so set up the signature. Sample the 1300 * parameter length before adding a signature algorithm. */ 1301 if (!CBB_flush(&cbb)) { 1302 goto err; 1303 } 1304 size_t params_len = CBB_len(&cbb); 1305 1306 /* Determine signature algorithm. */ 1307 const EVP_MD *md; 1308 if (SSL_USE_SIGALGS(ssl)) { 1309 md = tls1_choose_signing_digest(ssl); 1310 if (!tls12_add_sigandhash(ssl, &cbb, md)) { 1311 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1312 ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); 1313 goto err; 1314 } 1315 } else if (ssl_private_key_type(ssl) == EVP_PKEY_RSA) { 1316 md = EVP_md5_sha1(); 1317 } else { 1318 md = EVP_sha1(); 1319 } 1320 1321 /* Compute the digest and sign it. */ 1322 uint8_t digest[EVP_MAX_MD_SIZE]; 1323 unsigned digest_len = 0; 1324 EVP_MD_CTX md_ctx; 1325 EVP_MD_CTX_init(&md_ctx); 1326 int digest_ret = 1327 EVP_DigestInit_ex(&md_ctx, md, NULL) && 1328 EVP_DigestUpdate(&md_ctx, ssl->s3->client_random, SSL3_RANDOM_SIZE) && 1329 EVP_DigestUpdate(&md_ctx, ssl->s3->server_random, SSL3_RANDOM_SIZE) && 1330 EVP_DigestUpdate(&md_ctx, CBB_data(&cbb), params_len) && 1331 EVP_DigestFinal_ex(&md_ctx, digest, &digest_len); 1332 EVP_MD_CTX_cleanup(&md_ctx); 1333 uint8_t *ptr; 1334 if (!digest_ret || 1335 !CBB_add_u16_length_prefixed(&cbb, &child) || 1336 !CBB_reserve(&child, &ptr, max_sig_len)) { 1337 goto err; 1338 } 1339 sign_result = ssl_private_key_sign(ssl, ptr, &sig_len, max_sig_len, md, 1340 digest, digest_len); 1341 } else { 1342 assert(ssl->state == SSL3_ST_SW_KEY_EXCH_B); 1343 1344 /* Retry the signature. */ 1345 uint8_t *ptr; 1346 if (!CBB_add_u16_length_prefixed(&cbb, &child) || 1347 !CBB_reserve(&child, &ptr, max_sig_len)) { 1348 goto err; 1349 } 1350 sign_result = 1351 ssl_private_key_sign_complete(ssl, ptr, &sig_len, max_sig_len); 1352 } 1353 1354 switch (sign_result) { 1355 case ssl_private_key_success: 1356 ssl->rwstate = SSL_NOTHING; 1357 if (!CBB_did_write(&child, sig_len)) { 1358 goto err; 1359 } 1360 break; 1361 case ssl_private_key_failure: 1362 ssl->rwstate = SSL_NOTHING; 1363 goto err; 1364 case ssl_private_key_retry: 1365 /* Discard the unfinished signature and save the state of |cbb| for the 1366 * next iteration. */ 1367 CBB_discard_child(&cbb); 1368 ssl->init_num = SSL_HM_HEADER_LENGTH(ssl) + CBB_len(&cbb); 1369 ssl->rwstate = SSL_PRIVATE_KEY_OPERATION; 1370 ssl->state = SSL3_ST_SW_KEY_EXCH_B; 1371 goto err; 1372 } 1373 } 1374 1375 size_t length; 1376 if (!CBB_finish(&cbb, NULL, &length) || 1377 !ssl_set_handshake_header(ssl, SSL3_MT_SERVER_KEY_EXCHANGE, length)) { 1378 goto err; 1379 } 1380 ssl->state = SSL3_ST_SW_KEY_EXCH_C; 1381 return ssl_do_write(ssl); 1382 1383 err: 1384 CBB_cleanup(&cbb); 1385 return -1; 1386 } 1387 1388 int ssl3_send_certificate_request(SSL *ssl) { 1389 uint8_t *p, *d; 1390 size_t i; 1391 int j, nl, off, n; 1392 STACK_OF(X509_NAME) *sk = NULL; 1393 X509_NAME *name; 1394 BUF_MEM *buf; 1395 1396 if (ssl->state == SSL3_ST_SW_CERT_REQ_A) { 1397 buf = ssl->init_buf; 1398 1399 d = p = ssl_handshake_start(ssl); 1400 1401 /* get the list of acceptable cert types */ 1402 p++; 1403 n = ssl3_get_req_cert_type(ssl, p); 1404 d[0] = n; 1405 p += n; 1406 n++; 1407 1408 if (SSL_USE_SIGALGS(ssl)) { 1409 const uint8_t *psigs; 1410 nl = tls12_get_psigalgs(ssl, &psigs); 1411 s2n(nl, p); 1412 memcpy(p, psigs, nl); 1413 p += nl; 1414 n += nl + 2; 1415 } 1416 1417 off = n; 1418 p += 2; 1419 n += 2; 1420 1421 sk = SSL_get_client_CA_list(ssl); 1422 nl = 0; 1423 if (sk != NULL) { 1424 for (i = 0; i < sk_X509_NAME_num(sk); i++) { 1425 name = sk_X509_NAME_value(sk, i); 1426 j = i2d_X509_NAME(name, NULL); 1427 if (!BUF_MEM_grow_clean(buf, SSL_HM_HEADER_LENGTH(ssl) + n + j + 2)) { 1428 OPENSSL_PUT_ERROR(SSL, ERR_R_BUF_LIB); 1429 goto err; 1430 } 1431 p = ssl_handshake_start(ssl) + n; 1432 s2n(j, p); 1433 i2d_X509_NAME(name, &p); 1434 n += 2 + j; 1435 nl += 2 + j; 1436 } 1437 } 1438 1439 /* else no CA names */ 1440 p = ssl_handshake_start(ssl) + off; 1441 s2n(nl, p); 1442 1443 if (!ssl_set_handshake_header(ssl, SSL3_MT_CERTIFICATE_REQUEST, n)) { 1444 goto err; 1445 } 1446 ssl->state = SSL3_ST_SW_CERT_REQ_B; 1447 } 1448 1449 /* SSL3_ST_SW_CERT_REQ_B */ 1450 return ssl_do_write(ssl); 1451 1452 err: 1453 return -1; 1454 } 1455 1456 int ssl3_get_client_key_exchange(SSL *ssl) { 1457 int al; 1458 CBS client_key_exchange; 1459 uint32_t alg_k; 1460 uint32_t alg_a; 1461 uint8_t *premaster_secret = NULL; 1462 size_t premaster_secret_len = 0; 1463 uint8_t *decrypt_buf = NULL; 1464 1465 unsigned psk_len = 0; 1466 uint8_t psk[PSK_MAX_PSK_LEN]; 1467 1468 if (ssl->state == SSL3_ST_SR_KEY_EXCH_A || 1469 ssl->state == SSL3_ST_SR_KEY_EXCH_B) { 1470 int ok; 1471 const long n = ssl->method->ssl_get_message( 1472 ssl, SSL3_ST_SR_KEY_EXCH_A, SSL3_ST_SR_KEY_EXCH_B, 1473 SSL3_MT_CLIENT_KEY_EXCHANGE, 2048 /* ??? */, ssl_hash_message, &ok); 1474 if (!ok) { 1475 return n; 1476 } 1477 } 1478 1479 CBS_init(&client_key_exchange, ssl->init_msg, ssl->init_num); 1480 alg_k = ssl->s3->tmp.new_cipher->algorithm_mkey; 1481 alg_a = ssl->s3->tmp.new_cipher->algorithm_auth; 1482 1483 /* If using a PSK key exchange, prepare the pre-shared key. */ 1484 if (alg_a & SSL_aPSK) { 1485 CBS psk_identity; 1486 1487 /* If using PSK, the ClientKeyExchange contains a psk_identity. If PSK, 1488 * then this is the only field in the message. */ 1489 if (!CBS_get_u16_length_prefixed(&client_key_exchange, &psk_identity) || 1490 ((alg_k & SSL_kPSK) && CBS_len(&client_key_exchange) != 0)) { 1491 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1492 al = SSL_AD_DECODE_ERROR; 1493 goto f_err; 1494 } 1495 1496 if (ssl->psk_server_callback == NULL) { 1497 OPENSSL_PUT_ERROR(SSL, SSL_R_PSK_NO_SERVER_CB); 1498 al = SSL_AD_INTERNAL_ERROR; 1499 goto f_err; 1500 } 1501 1502 if (CBS_len(&psk_identity) > PSK_MAX_IDENTITY_LEN || 1503 CBS_contains_zero_byte(&psk_identity)) { 1504 OPENSSL_PUT_ERROR(SSL, SSL_R_DATA_LENGTH_TOO_LONG); 1505 al = SSL_AD_ILLEGAL_PARAMETER; 1506 goto f_err; 1507 } 1508 1509 if (!CBS_strdup(&psk_identity, &ssl->session->psk_identity)) { 1510 al = SSL_AD_INTERNAL_ERROR; 1511 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1512 goto f_err; 1513 } 1514 1515 /* Look up the key for the identity. */ 1516 psk_len = ssl->psk_server_callback(ssl, ssl->session->psk_identity, psk, 1517 sizeof(psk)); 1518 if (psk_len > PSK_MAX_PSK_LEN) { 1519 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); 1520 al = SSL_AD_INTERNAL_ERROR; 1521 goto f_err; 1522 } else if (psk_len == 0) { 1523 /* PSK related to the given identity not found */ 1524 OPENSSL_PUT_ERROR(SSL, SSL_R_PSK_IDENTITY_NOT_FOUND); 1525 al = SSL_AD_UNKNOWN_PSK_IDENTITY; 1526 goto f_err; 1527 } 1528 } 1529 1530 /* Depending on the key exchange method, compute |premaster_secret| and 1531 * |premaster_secret_len|. */ 1532 if (alg_k & SSL_kRSA) { 1533 /* Allocate a buffer large enough for an RSA decryption. */ 1534 const size_t rsa_size = ssl_private_key_max_signature_len(ssl); 1535 decrypt_buf = OPENSSL_malloc(rsa_size); 1536 if (decrypt_buf == NULL) { 1537 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1538 goto err; 1539 } 1540 1541 enum ssl_private_key_result_t decrypt_result; 1542 size_t decrypt_len; 1543 if (ssl->state == SSL3_ST_SR_KEY_EXCH_B) { 1544 if (!ssl_has_private_key(ssl) || 1545 ssl_private_key_type(ssl) != EVP_PKEY_RSA) { 1546 al = SSL_AD_HANDSHAKE_FAILURE; 1547 OPENSSL_PUT_ERROR(SSL, SSL_R_MISSING_RSA_CERTIFICATE); 1548 goto f_err; 1549 } 1550 CBS encrypted_premaster_secret; 1551 if (ssl->version > SSL3_VERSION) { 1552 if (!CBS_get_u16_length_prefixed(&client_key_exchange, 1553 &encrypted_premaster_secret) || 1554 CBS_len(&client_key_exchange) != 0) { 1555 al = SSL_AD_DECODE_ERROR; 1556 OPENSSL_PUT_ERROR(SSL, 1557 SSL_R_TLS_RSA_ENCRYPTED_VALUE_LENGTH_IS_WRONG); 1558 goto f_err; 1559 } 1560 } else { 1561 encrypted_premaster_secret = client_key_exchange; 1562 } 1563 1564 /* Decrypt with no padding. PKCS#1 padding will be removed as part of the 1565 * timing-sensitive code below. */ 1566 decrypt_result = ssl_private_key_decrypt( 1567 ssl, decrypt_buf, &decrypt_len, rsa_size, 1568 CBS_data(&encrypted_premaster_secret), 1569 CBS_len(&encrypted_premaster_secret)); 1570 } else { 1571 assert(ssl->state == SSL3_ST_SR_KEY_EXCH_C); 1572 /* Complete async decrypt. */ 1573 decrypt_result = ssl_private_key_decrypt_complete( 1574 ssl, decrypt_buf, &decrypt_len, rsa_size); 1575 } 1576 1577 switch (decrypt_result) { 1578 case ssl_private_key_success: 1579 ssl->rwstate = SSL_NOTHING; 1580 break; 1581 case ssl_private_key_failure: 1582 ssl->rwstate = SSL_NOTHING; 1583 goto err; 1584 case ssl_private_key_retry: 1585 ssl->rwstate = SSL_PRIVATE_KEY_OPERATION; 1586 ssl->state = SSL3_ST_SR_KEY_EXCH_C; 1587 goto err; 1588 } 1589 1590 assert(decrypt_len == rsa_size); 1591 1592 /* Prepare a random premaster, to be used on invalid padding. See RFC 5246, 1593 * section 7.4.7.1. */ 1594 premaster_secret_len = SSL_MAX_MASTER_KEY_LENGTH; 1595 premaster_secret = OPENSSL_malloc(premaster_secret_len); 1596 if (premaster_secret == NULL) { 1597 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1598 goto err; 1599 } 1600 if (!RAND_bytes(premaster_secret, premaster_secret_len)) { 1601 goto err; 1602 } 1603 1604 /* The smallest padded premaster is 11 bytes of overhead. Small keys are 1605 * publicly invalid. */ 1606 if (decrypt_len < 11 + premaster_secret_len) { 1607 al = SSL_AD_DECRYPT_ERROR; 1608 OPENSSL_PUT_ERROR(SSL, SSL_R_DECRYPTION_FAILED); 1609 goto f_err; 1610 } 1611 1612 /* Check the padding. See RFC 3447, section 7.2.2. */ 1613 size_t padding_len = decrypt_len - premaster_secret_len; 1614 uint8_t good = constant_time_eq_int_8(decrypt_buf[0], 0) & 1615 constant_time_eq_int_8(decrypt_buf[1], 2); 1616 size_t i; 1617 for (i = 2; i < padding_len - 1; i++) { 1618 good &= ~constant_time_is_zero_8(decrypt_buf[i]); 1619 } 1620 good &= constant_time_is_zero_8(decrypt_buf[padding_len - 1]); 1621 1622 /* The premaster secret must begin with |client_version|. This too must be 1623 * checked in constant time (http://eprint.iacr.org/2003/052/). */ 1624 good &= constant_time_eq_8(decrypt_buf[padding_len], 1625 (unsigned)(ssl->client_version >> 8)); 1626 good &= constant_time_eq_8(decrypt_buf[padding_len + 1], 1627 (unsigned)(ssl->client_version & 0xff)); 1628 1629 /* Select, in constant time, either the decrypted premaster or the random 1630 * premaster based on |good|. */ 1631 for (i = 0; i < premaster_secret_len; i++) { 1632 premaster_secret[i] = constant_time_select_8( 1633 good, decrypt_buf[padding_len + i], premaster_secret[i]); 1634 } 1635 1636 OPENSSL_free(decrypt_buf); 1637 decrypt_buf = NULL; 1638 } else if (alg_k & (SSL_kECDHE|SSL_kDHE)) { 1639 /* Parse the ClientKeyExchange. ECDHE uses a u8 length prefix while DHE uses 1640 * u16. */ 1641 CBS peer_key; 1642 int peer_key_ok; 1643 if (alg_k & SSL_kECDHE) { 1644 peer_key_ok = CBS_get_u8_length_prefixed(&client_key_exchange, &peer_key); 1645 } else { 1646 peer_key_ok = 1647 CBS_get_u16_length_prefixed(&client_key_exchange, &peer_key); 1648 } 1649 1650 if (!peer_key_ok || CBS_len(&client_key_exchange) != 0) { 1651 al = SSL_AD_DECODE_ERROR; 1652 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1653 goto f_err; 1654 } 1655 1656 /* Compute the premaster. */ 1657 uint8_t alert; 1658 if (!SSL_ECDH_CTX_compute_secret(&ssl->s3->tmp.ecdh_ctx, &premaster_secret, 1659 &premaster_secret_len, &alert, 1660 CBS_data(&peer_key), CBS_len(&peer_key))) { 1661 al = alert; 1662 goto f_err; 1663 } 1664 1665 /* The key exchange state may now be discarded. */ 1666 SSL_ECDH_CTX_cleanup(&ssl->s3->tmp.ecdh_ctx); 1667 } else if (alg_k & SSL_kPSK) { 1668 /* For plain PSK, other_secret is a block of 0s with the same length as the 1669 * pre-shared key. */ 1670 premaster_secret_len = psk_len; 1671 premaster_secret = OPENSSL_malloc(premaster_secret_len); 1672 if (premaster_secret == NULL) { 1673 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1674 goto err; 1675 } 1676 memset(premaster_secret, 0, premaster_secret_len); 1677 } else { 1678 al = SSL_AD_HANDSHAKE_FAILURE; 1679 OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_CIPHER_TYPE); 1680 goto f_err; 1681 } 1682 1683 /* For a PSK cipher suite, the actual pre-master secret is combined with the 1684 * pre-shared key. */ 1685 if (alg_a & SSL_aPSK) { 1686 CBB new_premaster, child; 1687 uint8_t *new_data; 1688 size_t new_len; 1689 1690 CBB_zero(&new_premaster); 1691 if (!CBB_init(&new_premaster, 2 + psk_len + 2 + premaster_secret_len) || 1692 !CBB_add_u16_length_prefixed(&new_premaster, &child) || 1693 !CBB_add_bytes(&child, premaster_secret, premaster_secret_len) || 1694 !CBB_add_u16_length_prefixed(&new_premaster, &child) || 1695 !CBB_add_bytes(&child, psk, psk_len) || 1696 !CBB_finish(&new_premaster, &new_data, &new_len)) { 1697 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1698 CBB_cleanup(&new_premaster); 1699 goto err; 1700 } 1701 1702 OPENSSL_cleanse(premaster_secret, premaster_secret_len); 1703 OPENSSL_free(premaster_secret); 1704 premaster_secret = new_data; 1705 premaster_secret_len = new_len; 1706 } 1707 1708 /* Compute the master secret */ 1709 ssl->session->master_key_length = ssl->enc_method->generate_master_secret( 1710 ssl, ssl->session->master_key, premaster_secret, premaster_secret_len); 1711 if (ssl->session->master_key_length == 0) { 1712 goto err; 1713 } 1714 ssl->session->extended_master_secret = ssl->s3->tmp.extended_master_secret; 1715 1716 OPENSSL_cleanse(premaster_secret, premaster_secret_len); 1717 OPENSSL_free(premaster_secret); 1718 return 1; 1719 1720 f_err: 1721 ssl3_send_alert(ssl, SSL3_AL_FATAL, al); 1722 err: 1723 if (premaster_secret != NULL) { 1724 OPENSSL_cleanse(premaster_secret, premaster_secret_len); 1725 OPENSSL_free(premaster_secret); 1726 } 1727 OPENSSL_free(decrypt_buf); 1728 1729 return -1; 1730 } 1731 1732 int ssl3_get_cert_verify(SSL *ssl) { 1733 int al, ok, ret = 0; 1734 long n; 1735 CBS certificate_verify, signature; 1736 X509 *peer = ssl->session->peer; 1737 EVP_PKEY *pkey = NULL; 1738 const EVP_MD *md = NULL; 1739 uint8_t digest[EVP_MAX_MD_SIZE]; 1740 size_t digest_length; 1741 EVP_PKEY_CTX *pctx = NULL; 1742 1743 /* Only RSA and ECDSA client certificates are supported, so a 1744 * CertificateVerify is required if and only if there's a client certificate. 1745 * */ 1746 if (peer == NULL) { 1747 ssl3_free_handshake_buffer(ssl); 1748 return 1; 1749 } 1750 1751 n = ssl->method->ssl_get_message( 1752 ssl, SSL3_ST_SR_CERT_VRFY_A, SSL3_ST_SR_CERT_VRFY_B, 1753 SSL3_MT_CERTIFICATE_VERIFY, SSL3_RT_MAX_PLAIN_LENGTH, 1754 ssl_dont_hash_message, &ok); 1755 1756 if (!ok) { 1757 return n; 1758 } 1759 1760 /* Filter out unsupported certificate types. */ 1761 pkey = X509_get_pubkey(peer); 1762 if (pkey == NULL) { 1763 goto err; 1764 } 1765 if (!(X509_certificate_type(peer, pkey) & EVP_PKT_SIGN) || 1766 (pkey->type != EVP_PKEY_RSA && pkey->type != EVP_PKEY_EC)) { 1767 al = SSL_AD_UNSUPPORTED_CERTIFICATE; 1768 OPENSSL_PUT_ERROR(SSL, SSL_R_PEER_ERROR_UNSUPPORTED_CERTIFICATE_TYPE); 1769 goto f_err; 1770 } 1771 1772 CBS_init(&certificate_verify, ssl->init_msg, n); 1773 1774 /* Determine the digest type if needbe. */ 1775 if (SSL_USE_SIGALGS(ssl)) { 1776 uint8_t hash, signature_type; 1777 if (!CBS_get_u8(&certificate_verify, &hash) || 1778 !CBS_get_u8(&certificate_verify, &signature_type)) { 1779 al = SSL_AD_DECODE_ERROR; 1780 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1781 goto f_err; 1782 } 1783 if (!tls12_check_peer_sigalg(ssl, &md, &al, hash, signature_type, pkey)) { 1784 goto f_err; 1785 } 1786 } 1787 1788 /* Compute the digest. */ 1789 if (!ssl3_cert_verify_hash(ssl, digest, &digest_length, &md, pkey->type)) { 1790 goto err; 1791 } 1792 1793 /* The handshake buffer is no longer necessary, and we may hash the current 1794 * message.*/ 1795 ssl3_free_handshake_buffer(ssl); 1796 if (!ssl3_hash_current_message(ssl)) { 1797 goto err; 1798 } 1799 1800 /* Parse and verify the signature. */ 1801 if (!CBS_get_u16_length_prefixed(&certificate_verify, &signature) || 1802 CBS_len(&certificate_verify) != 0) { 1803 al = SSL_AD_DECODE_ERROR; 1804 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1805 goto f_err; 1806 } 1807 1808 pctx = EVP_PKEY_CTX_new(pkey, NULL); 1809 if (pctx == NULL) { 1810 goto err; 1811 } 1812 if (!EVP_PKEY_verify_init(pctx) || 1813 !EVP_PKEY_CTX_set_signature_md(pctx, md) || 1814 !EVP_PKEY_verify(pctx, CBS_data(&signature), CBS_len(&signature), digest, 1815 digest_length)) { 1816 al = SSL_AD_DECRYPT_ERROR; 1817 OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_SIGNATURE); 1818 goto f_err; 1819 } 1820 1821 ret = 1; 1822 1823 if (0) { 1824 f_err: 1825 ssl3_send_alert(ssl, SSL3_AL_FATAL, al); 1826 } 1827 1828 err: 1829 EVP_PKEY_CTX_free(pctx); 1830 EVP_PKEY_free(pkey); 1831 1832 return ret; 1833 } 1834 1835 int ssl3_get_client_certificate(SSL *ssl) { 1836 int i, ok, al, ret = -1; 1837 X509 *x = NULL; 1838 unsigned long n; 1839 STACK_OF(X509) *sk = NULL; 1840 SHA256_CTX sha256; 1841 CBS certificate_msg, certificate_list; 1842 int is_first_certificate = 1; 1843 1844 n = ssl->method->ssl_get_message(ssl, SSL3_ST_SR_CERT_A, SSL3_ST_SR_CERT_B, 1845 -1, (long)ssl->max_cert_list, 1846 ssl_hash_message, &ok); 1847 1848 if (!ok) { 1849 return n; 1850 } 1851 1852 if (ssl->s3->tmp.message_type == SSL3_MT_CLIENT_KEY_EXCHANGE) { 1853 if ((ssl->verify_mode & SSL_VERIFY_PEER) && 1854 (ssl->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { 1855 OPENSSL_PUT_ERROR(SSL, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); 1856 al = SSL_AD_HANDSHAKE_FAILURE; 1857 goto f_err; 1858 } 1859 1860 /* If tls asked for a client cert, the client must return a 0 list */ 1861 if (ssl->version > SSL3_VERSION && ssl->s3->tmp.cert_request) { 1862 OPENSSL_PUT_ERROR(SSL, 1863 SSL_R_TLS_PEER_DID_NOT_RESPOND_WITH_CERTIFICATE_LIST); 1864 al = SSL_AD_UNEXPECTED_MESSAGE; 1865 goto f_err; 1866 } 1867 ssl->s3->tmp.reuse_message = 1; 1868 1869 return 1; 1870 } 1871 1872 if (ssl->s3->tmp.message_type != SSL3_MT_CERTIFICATE) { 1873 al = SSL_AD_UNEXPECTED_MESSAGE; 1874 OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_MESSAGE_TYPE); 1875 goto f_err; 1876 } 1877 1878 CBS_init(&certificate_msg, ssl->init_msg, n); 1879 1880 sk = sk_X509_new_null(); 1881 if (sk == NULL) { 1882 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1883 goto err; 1884 } 1885 1886 if (!CBS_get_u24_length_prefixed(&certificate_msg, &certificate_list) || 1887 CBS_len(&certificate_msg) != 0) { 1888 al = SSL_AD_DECODE_ERROR; 1889 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1890 goto f_err; 1891 } 1892 1893 while (CBS_len(&certificate_list) > 0) { 1894 CBS certificate; 1895 const uint8_t *data; 1896 1897 if (!CBS_get_u24_length_prefixed(&certificate_list, &certificate)) { 1898 al = SSL_AD_DECODE_ERROR; 1899 OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); 1900 goto f_err; 1901 } 1902 1903 if (is_first_certificate && ssl->ctx->retain_only_sha256_of_client_certs) { 1904 /* If this is the first certificate, and we don't want to keep peer 1905 * certificates in memory, then we hash it right away. */ 1906 SHA256_Init(&sha256); 1907 SHA256_Update(&sha256, CBS_data(&certificate), CBS_len(&certificate)); 1908 SHA256_Final(ssl->session->peer_sha256, &sha256); 1909 ssl->session->peer_sha256_valid = 1; 1910 } 1911 is_first_certificate = 0; 1912 1913 /* A u24 length cannot overflow a long. */ 1914 data = CBS_data(&certificate); 1915 x = d2i_X509(NULL, &data, (long)CBS_len(&certificate)); 1916 if (x == NULL) { 1917 al = SSL_AD_BAD_CERTIFICATE; 1918 OPENSSL_PUT_ERROR(SSL, ERR_R_ASN1_LIB); 1919 goto f_err; 1920 } 1921 if (data != CBS_data(&certificate) + CBS_len(&certificate)) { 1922 al = SSL_AD_DECODE_ERROR; 1923 OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_LENGTH_MISMATCH); 1924 goto f_err; 1925 } 1926 if (!sk_X509_push(sk, x)) { 1927 OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); 1928 goto err; 1929 } 1930 x = NULL; 1931 } 1932 1933 if (sk_X509_num(sk) <= 0) { 1934 /* No client certificate so the handshake buffer may be discarded. */ 1935 ssl3_free_handshake_buffer(ssl); 1936 1937 /* TLS does not mind 0 certs returned */ 1938 if (ssl->version == SSL3_VERSION) { 1939 al = SSL_AD_HANDSHAKE_FAILURE; 1940 OPENSSL_PUT_ERROR(SSL, SSL_R_NO_CERTIFICATES_RETURNED); 1941 goto f_err; 1942 } else if ((ssl->verify_mode & SSL_VERIFY_PEER) && 1943 (ssl->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { 1944 /* Fail for TLS only if we required a certificate */ 1945 OPENSSL_PUT_ERROR(SSL, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); 1946 al = SSL_AD_HANDSHAKE_FAILURE; 1947 goto f_err; 1948 } 1949 } else { 1950 i = ssl_verify_cert_chain(ssl, sk); 1951 if (i <= 0) { 1952 al = ssl_verify_alarm_type(ssl->verify_result); 1953 OPENSSL_PUT_ERROR(SSL, SSL_R_CERTIFICATE_VERIFY_FAILED); 1954 goto f_err; 1955 } 1956 } 1957 1958 X509_free(ssl->session->peer); 1959 ssl->session->peer = sk_X509_shift(sk); 1960 ssl->session->verify_result = ssl->verify_result; 1961 1962 sk_X509_pop_free(ssl->session->cert_chain, X509_free); 1963 ssl->session->cert_chain = sk; 1964 /* Inconsistency alert: cert_chain does *not* include the peer's own 1965 * certificate, while we do include it in s3_clnt.c */ 1966 1967 sk = NULL; 1968 1969 ret = 1; 1970 1971 if (0) { 1972 f_err: 1973 ssl3_send_alert(ssl, SSL3_AL_FATAL, al); 1974 } 1975 1976 err: 1977 X509_free(x); 1978 sk_X509_pop_free(sk, X509_free); 1979 return ret; 1980 } 1981 1982 int ssl3_send_server_certificate(SSL *ssl) { 1983 if (ssl->state == SSL3_ST_SW_CERT_A) { 1984 if (!ssl3_output_cert_chain(ssl)) { 1985 return 0; 1986 } 1987 ssl->state = SSL3_ST_SW_CERT_B; 1988 } 1989 1990 /* SSL3_ST_SW_CERT_B */ 1991 return ssl_do_write(ssl); 1992 } 1993 1994 /* send a new session ticket (not necessarily for a new session) */ 1995 int ssl3_send_new_session_ticket(SSL *ssl) { 1996 int ret = -1; 1997 uint8_t *session = NULL; 1998 size_t session_len; 1999 EVP_CIPHER_CTX ctx; 2000 HMAC_CTX hctx; 2001 2002 EVP_CIPHER_CTX_init(&ctx); 2003 HMAC_CTX_init(&hctx); 2004 2005 if (ssl->state == SSL3_ST_SW_SESSION_TICKET_A) { 2006 uint8_t *p, *macstart; 2007 int len; 2008 unsigned int hlen; 2009 SSL_CTX *tctx = ssl->initial_ctx; 2010 uint8_t iv[EVP_MAX_IV_LENGTH]; 2011 uint8_t key_name[16]; 2012 /* The maximum overhead of encrypting the session is 16 (key name) + IV + 2013 * one block of encryption overhead + HMAC. */ 2014 const size_t max_ticket_overhead = 2015 16 + EVP_MAX_IV_LENGTH + EVP_MAX_BLOCK_LENGTH + EVP_MAX_MD_SIZE; 2016 2017 /* Serialize the SSL_SESSION to be encoded into the ticket. */ 2018 if (!SSL_SESSION_to_bytes_for_ticket(ssl->session, &session, 2019 &session_len)) { 2020 goto err; 2021 } 2022 2023 /* If the session is too long, emit a dummy value rather than abort the 2024 * connection. */ 2025 if (session_len > 0xFFFF - max_ticket_overhead) { 2026 static const char kTicketPlaceholder[] = "TICKET TOO LARGE"; 2027 const size_t placeholder_len = strlen(kTicketPlaceholder); 2028 2029 OPENSSL_free(session); 2030 session = NULL; 2031 2032 p = ssl_handshake_start(ssl); 2033 /* Emit ticket_lifetime_hint. */ 2034 l2n(0, p); 2035 /* Emit ticket. */ 2036 s2n(placeholder_len, p); 2037 memcpy(p, kTicketPlaceholder, placeholder_len); 2038 p += placeholder_len; 2039 2040 len = p - ssl_handshake_start(ssl); 2041 if (!ssl_set_handshake_header(ssl, SSL3_MT_NEWSESSION_TICKET, len)) { 2042 goto err; 2043 } 2044 ssl->state = SSL3_ST_SW_SESSION_TICKET_B; 2045 return ssl_do_write(ssl); 2046 } 2047 2048 /* Grow buffer if need be: the length calculation is as follows: 2049 * handshake_header_length + 4 (ticket lifetime hint) + 2 (ticket length) + 2050 * max_ticket_overhead + * session_length */ 2051 if (!BUF_MEM_grow(ssl->init_buf, SSL_HM_HEADER_LENGTH(ssl) + 6 + 2052 max_ticket_overhead + session_len)) { 2053 goto err; 2054 } 2055 p = ssl_handshake_start(ssl); 2056 /* Initialize HMAC and cipher contexts. If callback present it does all the 2057 * work otherwise use generated values from parent ctx. */ 2058 if (tctx->tlsext_ticket_key_cb) { 2059 if (tctx->tlsext_ticket_key_cb(ssl, key_name, iv, &ctx, &hctx, 2060 1 /* encrypt */) < 0) { 2061 goto err; 2062 } 2063 } else { 2064 if (!RAND_bytes(iv, 16) || 2065 !EVP_EncryptInit_ex(&ctx, EVP_aes_128_cbc(), NULL, 2066 tctx->tlsext_tick_aes_key, iv) || 2067 !HMAC_Init_ex(&hctx, tctx->tlsext_tick_hmac_key, 16, tlsext_tick_md(), 2068 NULL)) { 2069 goto err; 2070 } 2071 memcpy(key_name, tctx->tlsext_tick_key_name, 16); 2072 } 2073 2074 /* Ticket lifetime hint (advisory only): We leave this unspecified for 2075 * resumed session (for simplicity), and guess that tickets for new 2076 * sessions will live as long as their sessions. */ 2077 l2n(ssl->hit ? 0 : ssl->session->timeout, p); 2078 2079 /* Skip ticket length for now */ 2080 p += 2; 2081 /* Output key name */ 2082 macstart = p; 2083 memcpy(p, key_name, 16); 2084 p += 16; 2085 /* output IV */ 2086 memcpy(p, iv, EVP_CIPHER_CTX_iv_length(&ctx)); 2087 p += EVP_CIPHER_CTX_iv_length(&ctx); 2088 /* Encrypt session data */ 2089 if (!EVP_EncryptUpdate(&ctx, p, &len, session, session_len)) { 2090 goto err; 2091 } 2092 p += len; 2093 if (!EVP_EncryptFinal_ex(&ctx, p, &len)) { 2094 goto err; 2095 } 2096 p += len; 2097 2098 if (!HMAC_Update(&hctx, macstart, p - macstart) || 2099 !HMAC_Final(&hctx, p, &hlen)) { 2100 goto err; 2101 } 2102 2103 p += hlen; 2104 /* Now write out lengths: p points to end of data written */ 2105 /* Total length */ 2106 len = p - ssl_handshake_start(ssl); 2107 /* Skip ticket lifetime hint */ 2108 p = ssl_handshake_start(ssl) + 4; 2109 s2n(len - 6, p); 2110 if (!ssl_set_handshake_header(ssl, SSL3_MT_NEWSESSION_TICKET, len)) { 2111 goto err; 2112 } 2113 ssl->state = SSL3_ST_SW_SESSION_TICKET_B; 2114 } 2115 2116 /* SSL3_ST_SW_SESSION_TICKET_B */ 2117 ret = ssl_do_write(ssl); 2118 2119 err: 2120 OPENSSL_free(session); 2121 EVP_CIPHER_CTX_cleanup(&ctx); 2122 HMAC_CTX_cleanup(&hctx); 2123 return ret; 2124 } 2125 2126 /* ssl3_get_next_proto reads a Next Protocol Negotiation handshake message. It 2127 * sets the next_proto member in s if found */ 2128 int ssl3_get_next_proto(SSL *ssl) { 2129 int ok; 2130 long n; 2131 CBS next_protocol, selected_protocol, padding; 2132 2133 /* Clients cannot send a NextProtocol message if we didn't see the extension 2134 * in their ClientHello */ 2135 if (!ssl->s3->next_proto_neg_seen) { 2136 OPENSSL_PUT_ERROR(SSL, SSL_R_GOT_NEXT_PROTO_WITHOUT_EXTENSION); 2137 return -1; 2138 } 2139 2140 n = ssl->method->ssl_get_message(ssl, SSL3_ST_SR_NEXT_PROTO_A, 2141 SSL3_ST_SR_NEXT_PROTO_B, SSL3_MT_NEXT_PROTO, 2142 514, /* See the payload format below */ 2143 ssl_hash_message, &ok); 2144 2145 if (!ok) { 2146 return n; 2147 } 2148 2149 CBS_init(&next_protocol, ssl->init_msg, n); 2150 2151 /* The payload looks like: 2152 * uint8 proto_len; 2153 * uint8 proto[proto_len]; 2154 * uint8 padding_len; 2155 * uint8 padding[padding_len]; */ 2156 if (!CBS_get_u8_length_prefixed(&next_protocol, &selected_protocol) || 2157 !CBS_get_u8_length_prefixed(&next_protocol, &padding) || 2158 CBS_len(&next_protocol) != 0 || 2159 !CBS_stow(&selected_protocol, &ssl->next_proto_negotiated, 2160 &ssl->next_proto_negotiated_len)) { 2161 return 0; 2162 } 2163 2164 return 1; 2165 } 2166 2167 /* ssl3_get_channel_id reads and verifies a ClientID handshake message. */ 2168 int ssl3_get_channel_id(SSL *ssl) { 2169 int ret = -1, ok; 2170 long n; 2171 uint8_t channel_id_hash[EVP_MAX_MD_SIZE]; 2172 size_t channel_id_hash_len; 2173 const uint8_t *p; 2174 uint16_t extension_type; 2175 EC_GROUP *p256 = NULL; 2176 EC_KEY *key = NULL; 2177 EC_POINT *point = NULL; 2178 ECDSA_SIG sig; 2179 BIGNUM x, y; 2180 CBS encrypted_extensions, extension; 2181 2182 n = ssl->method->ssl_get_message( 2183 ssl, SSL3_ST_SR_CHANNEL_ID_A, SSL3_ST_SR_CHANNEL_ID_B, 2184 SSL3_MT_ENCRYPTED_EXTENSIONS, 2 + 2 + TLSEXT_CHANNEL_ID_SIZE, 2185 ssl_dont_hash_message, &ok); 2186 2187 if (!ok) { 2188 return n; 2189 } 2190 2191 /* Before incorporating the EncryptedExtensions message to the handshake 2192 * hash, compute the hash that should have been signed. */ 2193 if (!tls1_channel_id_hash(ssl, channel_id_hash, &channel_id_hash_len)) { 2194 return -1; 2195 } 2196 assert(channel_id_hash_len == SHA256_DIGEST_LENGTH); 2197 2198 if (!ssl3_hash_current_message(ssl)) { 2199 return -1; 2200 } 2201 2202 CBS_init(&encrypted_extensions, ssl->init_msg, n); 2203 2204 /* EncryptedExtensions could include multiple extensions, but the only 2205 * extension that could be negotiated is ChannelID, so there can only be one 2206 * entry. 2207 * 2208 * The payload looks like: 2209 * uint16 extension_type 2210 * uint16 extension_len; 2211 * uint8 x[32]; 2212 * uint8 y[32]; 2213 * uint8 r[32]; 2214 * uint8 s[32]; */ 2215 2216 if (!CBS_get_u16(&encrypted_extensions, &extension_type) || 2217 !CBS_get_u16_length_prefixed(&encrypted_extensions, &extension) || 2218 CBS_len(&encrypted_extensions) != 0 || 2219 extension_type != TLSEXT_TYPE_channel_id || 2220 CBS_len(&extension) != TLSEXT_CHANNEL_ID_SIZE) { 2221 OPENSSL_PUT_ERROR(SSL, SSL_R_INVALID_MESSAGE); 2222 return -1; 2223 } 2224 2225 p256 = EC_GROUP_new_by_curve_name(NID_X9_62_prime256v1); 2226 if (!p256) { 2227 OPENSSL_PUT_ERROR(SSL, SSL_R_NO_P256_SUPPORT); 2228 return -1; 2229 } 2230 2231 BN_init(&x); 2232 BN_init(&y); 2233 sig.r = BN_new(); 2234 sig.s = BN_new(); 2235 if (sig.r == NULL || sig.s == NULL) { 2236 goto err; 2237 } 2238 2239 p = CBS_data(&extension); 2240 if (BN_bin2bn(p + 0, 32, &x) == NULL || 2241 BN_bin2bn(p + 32, 32, &y) == NULL || 2242 BN_bin2bn(p + 64, 32, sig.r) == NULL || 2243 BN_bin2bn(p + 96, 32, sig.s) == NULL) { 2244 goto err; 2245 } 2246 2247 point = EC_POINT_new(p256); 2248 if (!point || 2249 !EC_POINT_set_affine_coordinates_GFp(p256, point, &x, &y, NULL)) { 2250 goto err; 2251 } 2252 2253 key = EC_KEY_new(); 2254 if (!key || !EC_KEY_set_group(key, p256) || 2255 !EC_KEY_set_public_key(key, point)) { 2256 goto err; 2257 } 2258 2259 /* We stored the handshake hash in |tlsext_channel_id| the first time that we 2260 * were called. */ 2261 if (!ECDSA_do_verify(channel_id_hash, channel_id_hash_len, &sig, key)) { 2262 OPENSSL_PUT_ERROR(SSL, SSL_R_CHANNEL_ID_SIGNATURE_INVALID); 2263 ssl->s3->tlsext_channel_id_valid = 0; 2264 goto err; 2265 } 2266 2267 memcpy(ssl->s3->tlsext_channel_id, p, 64); 2268 ret = 1; 2269 2270 err: 2271 BN_free(&x); 2272 BN_free(&y); 2273 BN_free(sig.r); 2274 BN_free(sig.s); 2275 EC_KEY_free(key); 2276 EC_POINT_free(point); 2277 EC_GROUP_free(p256); 2278 return ret; 2279 } 2280
