1 /* $OpenBSD: ssl_srvr.c,v 1.127 2021/12/04 14:03:22 jsing Exp $ */ 2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay@cryptsoft.com). 7 * The implementation was written so as to conform with Netscapes SSL. 8 * 9 * This library is free for commercial and non-commercial use as long as 10 * the following conditions are aheared to. The following conditions 11 * apply to all code found in this distribution, be it the RC4, RSA, 12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13 * included with this distribution is covered by the same copyright terms 14 * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15 * 16 * Copyright remains Eric Young's, and as such any Copyright notices in 17 * the code are not to be removed. 18 * If this package is used in a product, Eric Young should be given attribution 19 * as the author of the parts of the library used. 20 * This can be in the form of a textual message at program startup or 21 * in documentation (online or textual) provided with the package. 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions 25 * are met: 26 * 1. Redistributions of source code must retain the copyright 27 * notice, this list of conditions and the following disclaimer. 28 * 2. Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in the 30 * documentation and/or other materials provided with the distribution. 31 * 3. All advertising materials mentioning features or use of this software 32 * must display the following acknowledgement: 33 * "This product includes cryptographic software written by 34 * Eric Young (eay@cryptsoft.com)" 35 * The word 'cryptographic' can be left out if the rouines from the library 36 * being used are not cryptographic related :-). 37 * 4. If you include any Windows specific code (or a derivative thereof) from 38 * the apps directory (application code) you must include an acknowledgement: 39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40 * 41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51 * SUCH DAMAGE. 52 * 53 * The licence and distribution terms for any publically available version or 54 * derivative of this code cannot be changed. i.e. this code cannot simply be 55 * copied and put under another distribution licence 56 * [including the GNU Public Licence.] 57 */ 58 /* ==================================================================== 59 * Copyright (c) 1998-2007 The OpenSSL Project. All rights reserved. 60 * 61 * Redistribution and use in source and binary forms, with or without 62 * modification, are permitted provided that the following conditions 63 * are met: 64 * 65 * 1. Redistributions of source code must retain the above copyright 66 * notice, this list of conditions and the following disclaimer. 67 * 68 * 2. Redistributions in binary form must reproduce the above copyright 69 * notice, this list of conditions and the following disclaimer in 70 * the documentation and/or other materials provided with the 71 * distribution. 72 * 73 * 3. All advertising materials mentioning features or use of this 74 * software must display the following acknowledgment: 75 * "This product includes software developed by the OpenSSL Project 76 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 77 * 78 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 79 * endorse or promote products derived from this software without 80 * prior written permission. For written permission, please contact 81 * openssl-core@openssl.org. 82 * 83 * 5. Products derived from this software may not be called "OpenSSL" 84 * nor may "OpenSSL" appear in their names without prior written 85 * permission of the OpenSSL Project. 86 * 87 * 6. Redistributions of any form whatsoever must retain the following 88 * acknowledgment: 89 * "This product includes software developed by the OpenSSL Project 90 * for use in the OpenSSL Toolkit (http://www.openssl.org/)" 91 * 92 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 93 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 94 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 95 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 96 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 97 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 98 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 99 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 100 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 101 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 102 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 103 * OF THE POSSIBILITY OF SUCH DAMAGE. 104 * ==================================================================== 105 * 106 * This product includes cryptographic software written by Eric Young 107 * (eay@cryptsoft.com). This product includes software written by Tim 108 * Hudson (tjh@cryptsoft.com). 109 * 110 */ 111 /* ==================================================================== 112 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. 113 * 114 * Portions of the attached software ("Contribution") are developed by 115 * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project. 116 * 117 * The Contribution is licensed pursuant to the OpenSSL open source 118 * license provided above. 119 * 120 * ECC cipher suite support in OpenSSL originally written by 121 * Vipul Gupta and Sumit Gupta of Sun Microsystems Laboratories. 122 * 123 */ 124 /* ==================================================================== 125 * Copyright 2005 Nokia. All rights reserved. 126 * 127 * The portions of the attached software ("Contribution") is developed by 128 * Nokia Corporation and is licensed pursuant to the OpenSSL open source 129 * license. 130 * 131 * The Contribution, originally written by Mika Kousa and Pasi Eronen of 132 * Nokia Corporation, consists of the "PSK" (Pre-Shared Key) ciphersuites 133 * support (see RFC 4279) to OpenSSL. 134 * 135 * No patent licenses or other rights except those expressly stated in 136 * the OpenSSL open source license shall be deemed granted or received 137 * expressly, by implication, estoppel, or otherwise. 138 * 139 * No assurances are provided by Nokia that the Contribution does not 140 * infringe the patent or other intellectual property rights of any third 141 * party or that the license provides you with all the necessary rights 142 * to make use of the Contribution. 143 * 144 * THE SOFTWARE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. IN 145 * ADDITION TO THE DISCLAIMERS INCLUDED IN THE LICENSE, NOKIA 146 * SPECIFICALLY DISCLAIMS ANY LIABILITY FOR CLAIMS BROUGHT BY YOU OR ANY 147 * OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OR 148 * OTHERWISE. 149 */ 150 151 #include <stdio.h> 152 153 #include <openssl/bn.h> 154 #include <openssl/buffer.h> 155 #include <openssl/curve25519.h> 156 #include <openssl/evp.h> 157 #include <openssl/dh.h> 158 #include <openssl/hmac.h> 159 #include <openssl/md5.h> 160 #include <openssl/objects.h> 161 #include <openssl/opensslconf.h> 162 #include <openssl/x509.h> 163 164 #ifndef OPENSSL_NO_GOST 165 #include <openssl/gost.h> 166 #endif 167 168 #include "bytestring.h" 169 #include "dtls_locl.h" 170 #include "ssl_locl.h" 171 #include "ssl_sigalgs.h" 172 #include "ssl_tlsext.h" 173 174 int 175 ssl3_accept(SSL *s) 176 { 177 unsigned long alg_k; 178 int new_state, state, skip = 0; 179 int listen = 0; 180 int ret = -1; 181 182 ERR_clear_error(); 183 errno = 0; 184 185 if (SSL_is_dtls(s)) 186 listen = s->d1->listen; 187 188 /* init things to blank */ 189 s->internal->in_handshake++; 190 if (!SSL_in_init(s) || SSL_in_before(s)) 191 SSL_clear(s); 192 193 if (SSL_is_dtls(s)) 194 s->d1->listen = listen; 195 196 for (;;) { 197 state = S3I(s)->hs.state; 198 199 switch (S3I(s)->hs.state) { 200 case SSL_ST_RENEGOTIATE: 201 s->internal->renegotiate = 1; 202 /* S3I(s)->hs.state=SSL_ST_ACCEPT; */ 203 204 case SSL_ST_BEFORE: 205 case SSL_ST_ACCEPT: 206 case SSL_ST_BEFORE|SSL_ST_ACCEPT: 207 case SSL_ST_OK|SSL_ST_ACCEPT: 208 s->server = 1; 209 210 ssl_info_callback(s, SSL_CB_HANDSHAKE_START, 1); 211 212 if (!ssl_legacy_stack_version(s, s->version)) { 213 SSLerror(s, ERR_R_INTERNAL_ERROR); 214 ret = -1; 215 goto end; 216 } 217 218 if (!ssl_supported_tls_version_range(s, 219 &S3I(s)->hs.our_min_tls_version, 220 &S3I(s)->hs.our_max_tls_version)) { 221 SSLerror(s, SSL_R_NO_PROTOCOLS_AVAILABLE); 222 ret = -1; 223 goto end; 224 } 225 226 if (!ssl3_setup_init_buffer(s)) { 227 ret = -1; 228 goto end; 229 } 230 if (!ssl3_setup_buffers(s)) { 231 ret = -1; 232 goto end; 233 } 234 235 s->internal->init_num = 0; 236 237 if (S3I(s)->hs.state != SSL_ST_RENEGOTIATE) { 238 /* 239 * Ok, we now need to push on a buffering BIO 240 * so that the output is sent in a way that 241 * TCP likes :-) 242 */ 243 if (!ssl_init_wbio_buffer(s, 1)) { 244 ret = -1; 245 goto end; 246 } 247 248 if (!tls1_transcript_init(s)) { 249 ret = -1; 250 goto end; 251 } 252 253 S3I(s)->hs.state = SSL3_ST_SR_CLNT_HELLO_A; 254 s->ctx->internal->stats.sess_accept++; 255 } else if (!SSL_is_dtls(s) && !S3I(s)->send_connection_binding) { 256 /* 257 * Server attempting to renegotiate with 258 * client that doesn't support secure 259 * renegotiation. 260 */ 261 SSLerror(s, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED); 262 ssl3_send_alert(s, SSL3_AL_FATAL, 263 SSL_AD_HANDSHAKE_FAILURE); 264 ret = -1; 265 goto end; 266 } else { 267 /* 268 * S3I(s)->hs.state == SSL_ST_RENEGOTIATE, 269 * we will just send a HelloRequest. 270 */ 271 s->ctx->internal->stats.sess_accept_renegotiate++; 272 S3I(s)->hs.state = SSL3_ST_SW_HELLO_REQ_A; 273 } 274 break; 275 276 case SSL3_ST_SW_HELLO_REQ_A: 277 case SSL3_ST_SW_HELLO_REQ_B: 278 s->internal->shutdown = 0; 279 if (SSL_is_dtls(s)) { 280 dtls1_clear_record_buffer(s); 281 dtls1_start_timer(s); 282 } 283 ret = ssl3_send_hello_request(s); 284 if (ret <= 0) 285 goto end; 286 if (SSL_is_dtls(s)) 287 S3I(s)->hs.tls12.next_state = SSL3_ST_SR_CLNT_HELLO_A; 288 else 289 S3I(s)->hs.tls12.next_state = SSL3_ST_SW_HELLO_REQ_C; 290 S3I(s)->hs.state = SSL3_ST_SW_FLUSH; 291 s->internal->init_num = 0; 292 293 if (SSL_is_dtls(s)) { 294 if (!tls1_transcript_init(s)) { 295 ret = -1; 296 goto end; 297 } 298 } 299 break; 300 301 case SSL3_ST_SW_HELLO_REQ_C: 302 S3I(s)->hs.state = SSL_ST_OK; 303 break; 304 305 case SSL3_ST_SR_CLNT_HELLO_A: 306 case SSL3_ST_SR_CLNT_HELLO_B: 307 case SSL3_ST_SR_CLNT_HELLO_C: 308 s->internal->shutdown = 0; 309 if (SSL_is_dtls(s)) { 310 ret = ssl3_get_client_hello(s); 311 if (ret <= 0) 312 goto end; 313 dtls1_stop_timer(s); 314 315 if (ret == 1 && 316 (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE)) 317 S3I(s)->hs.state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A; 318 else 319 S3I(s)->hs.state = SSL3_ST_SW_SRVR_HELLO_A; 320 321 s->internal->init_num = 0; 322 323 /* 324 * Reflect ClientHello sequence to remain 325 * stateless while listening. 326 */ 327 if (listen) { 328 tls12_record_layer_reflect_seq_num( 329 s->internal->rl); 330 } 331 332 /* If we're just listening, stop here */ 333 if (listen && S3I(s)->hs.state == SSL3_ST_SW_SRVR_HELLO_A) { 334 ret = 2; 335 s->d1->listen = 0; 336 /* 337 * Set expected sequence numbers to 338 * continue the handshake. 339 */ 340 s->d1->handshake_read_seq = 2; 341 s->d1->handshake_write_seq = 1; 342 s->d1->next_handshake_write_seq = 1; 343 goto end; 344 } 345 } else { 346 if (s->internal->rwstate != SSL_X509_LOOKUP) { 347 ret = ssl3_get_client_hello(s); 348 if (ret <= 0) 349 goto end; 350 } 351 352 s->internal->renegotiate = 2; 353 S3I(s)->hs.state = SSL3_ST_SW_SRVR_HELLO_A; 354 s->internal->init_num = 0; 355 } 356 break; 357 358 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A: 359 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B: 360 ret = ssl3_send_dtls_hello_verify_request(s); 361 if (ret <= 0) 362 goto end; 363 S3I(s)->hs.state = SSL3_ST_SW_FLUSH; 364 S3I(s)->hs.tls12.next_state = SSL3_ST_SR_CLNT_HELLO_A; 365 366 /* HelloVerifyRequest resets Finished MAC. */ 367 tls1_transcript_reset(s); 368 break; 369 370 case SSL3_ST_SW_SRVR_HELLO_A: 371 case SSL3_ST_SW_SRVR_HELLO_B: 372 if (SSL_is_dtls(s)) { 373 s->internal->renegotiate = 2; 374 dtls1_start_timer(s); 375 } 376 ret = ssl3_send_server_hello(s); 377 if (ret <= 0) 378 goto end; 379 if (s->internal->hit) { 380 if (s->internal->tlsext_ticket_expected) 381 S3I(s)->hs.state = SSL3_ST_SW_SESSION_TICKET_A; 382 else 383 S3I(s)->hs.state = SSL3_ST_SW_CHANGE_A; 384 } else { 385 S3I(s)->hs.state = SSL3_ST_SW_CERT_A; 386 } 387 s->internal->init_num = 0; 388 break; 389 390 case SSL3_ST_SW_CERT_A: 391 case SSL3_ST_SW_CERT_B: 392 /* Check if it is anon DH or anon ECDH. */ 393 if (!(S3I(s)->hs.cipher->algorithm_auth & 394 SSL_aNULL)) { 395 if (SSL_is_dtls(s)) 396 dtls1_start_timer(s); 397 ret = ssl3_send_server_certificate(s); 398 if (ret <= 0) 399 goto end; 400 if (s->internal->tlsext_status_expected) 401 S3I(s)->hs.state = SSL3_ST_SW_CERT_STATUS_A; 402 else 403 S3I(s)->hs.state = SSL3_ST_SW_KEY_EXCH_A; 404 } else { 405 skip = 1; 406 S3I(s)->hs.state = SSL3_ST_SW_KEY_EXCH_A; 407 } 408 s->internal->init_num = 0; 409 break; 410 411 case SSL3_ST_SW_KEY_EXCH_A: 412 case SSL3_ST_SW_KEY_EXCH_B: 413 alg_k = S3I(s)->hs.cipher->algorithm_mkey; 414 415 /* 416 * Only send if using a DH key exchange. 417 * 418 * For ECC ciphersuites, we send a ServerKeyExchange 419 * message only if the cipher suite is ECDHE. In other 420 * cases, the server certificate contains the server's 421 * public key for key exchange. 422 */ 423 if (alg_k & (SSL_kDHE|SSL_kECDHE)) { 424 if (SSL_is_dtls(s)) 425 dtls1_start_timer(s); 426 ret = ssl3_send_server_key_exchange(s); 427 if (ret <= 0) 428 goto end; 429 } else 430 skip = 1; 431 432 S3I(s)->hs.state = SSL3_ST_SW_CERT_REQ_A; 433 s->internal->init_num = 0; 434 break; 435 436 case SSL3_ST_SW_CERT_REQ_A: 437 case SSL3_ST_SW_CERT_REQ_B: 438 /* 439 * Determine whether or not we need to request a 440 * certificate. 441 * 442 * Do not request a certificate if: 443 * 444 * - We did not ask for it (SSL_VERIFY_PEER is unset). 445 * 446 * - SSL_VERIFY_CLIENT_ONCE is set and we are 447 * renegotiating. 448 * 449 * - We are using an anonymous ciphersuites 450 * (see section "Certificate request" in SSL 3 drafts 451 * and in RFC 2246) ... except when the application 452 * insists on verification (against the specs, but 453 * s3_clnt.c accepts this for SSL 3). 454 */ 455 if (!(s->verify_mode & SSL_VERIFY_PEER) || 456 ((s->session->peer != NULL) && 457 (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) || 458 ((S3I(s)->hs.cipher->algorithm_auth & 459 SSL_aNULL) && !(s->verify_mode & 460 SSL_VERIFY_FAIL_IF_NO_PEER_CERT))) { 461 /* No cert request. */ 462 skip = 1; 463 S3I(s)->hs.tls12.cert_request = 0; 464 S3I(s)->hs.state = SSL3_ST_SW_SRVR_DONE_A; 465 466 if (!SSL_is_dtls(s)) 467 tls1_transcript_free(s); 468 } else { 469 S3I(s)->hs.tls12.cert_request = 1; 470 if (SSL_is_dtls(s)) 471 dtls1_start_timer(s); 472 ret = ssl3_send_certificate_request(s); 473 if (ret <= 0) 474 goto end; 475 S3I(s)->hs.state = SSL3_ST_SW_SRVR_DONE_A; 476 s->internal->init_num = 0; 477 } 478 break; 479 480 case SSL3_ST_SW_SRVR_DONE_A: 481 case SSL3_ST_SW_SRVR_DONE_B: 482 if (SSL_is_dtls(s)) 483 dtls1_start_timer(s); 484 ret = ssl3_send_server_done(s); 485 if (ret <= 0) 486 goto end; 487 S3I(s)->hs.tls12.next_state = SSL3_ST_SR_CERT_A; 488 S3I(s)->hs.state = SSL3_ST_SW_FLUSH; 489 s->internal->init_num = 0; 490 break; 491 492 case SSL3_ST_SW_FLUSH: 493 /* 494 * This code originally checked to see if 495 * any data was pending using BIO_CTRL_INFO 496 * and then flushed. This caused problems 497 * as documented in PR#1939. The proposed 498 * fix doesn't completely resolve this issue 499 * as buggy implementations of BIO_CTRL_PENDING 500 * still exist. So instead we just flush 501 * unconditionally. 502 */ 503 s->internal->rwstate = SSL_WRITING; 504 if (BIO_flush(s->wbio) <= 0) { 505 if (SSL_is_dtls(s)) { 506 /* If the write error was fatal, stop trying. */ 507 if (!BIO_should_retry(s->wbio)) { 508 s->internal->rwstate = SSL_NOTHING; 509 S3I(s)->hs.state = S3I(s)->hs.tls12.next_state; 510 } 511 } 512 ret = -1; 513 goto end; 514 } 515 s->internal->rwstate = SSL_NOTHING; 516 S3I(s)->hs.state = S3I(s)->hs.tls12.next_state; 517 break; 518 519 case SSL3_ST_SR_CERT_A: 520 case SSL3_ST_SR_CERT_B: 521 if (S3I(s)->hs.tls12.cert_request) { 522 ret = ssl3_get_client_certificate(s); 523 if (ret <= 0) 524 goto end; 525 } 526 s->internal->init_num = 0; 527 S3I(s)->hs.state = SSL3_ST_SR_KEY_EXCH_A; 528 break; 529 530 case SSL3_ST_SR_KEY_EXCH_A: 531 case SSL3_ST_SR_KEY_EXCH_B: 532 ret = ssl3_get_client_key_exchange(s); 533 if (ret <= 0) 534 goto end; 535 536 if (SSL_is_dtls(s)) { 537 S3I(s)->hs.state = SSL3_ST_SR_CERT_VRFY_A; 538 s->internal->init_num = 0; 539 } 540 541 alg_k = S3I(s)->hs.cipher->algorithm_mkey; 542 if (ret == 2) { 543 /* 544 * For the ECDH ciphersuites when 545 * the client sends its ECDH pub key in 546 * a certificate, the CertificateVerify 547 * message is not sent. 548 * Also for GOST ciphersuites when 549 * the client uses its key from the certificate 550 * for key exchange. 551 */ 552 S3I(s)->hs.state = SSL3_ST_SR_FINISHED_A; 553 s->internal->init_num = 0; 554 } else if (SSL_USE_SIGALGS(s) || (alg_k & SSL_kGOST)) { 555 S3I(s)->hs.state = SSL3_ST_SR_CERT_VRFY_A; 556 s->internal->init_num = 0; 557 if (!s->session->peer) 558 break; 559 /* 560 * Freeze the transcript for use during client 561 * certificate verification. 562 */ 563 tls1_transcript_freeze(s); 564 } else { 565 S3I(s)->hs.state = SSL3_ST_SR_CERT_VRFY_A; 566 s->internal->init_num = 0; 567 568 tls1_transcript_free(s); 569 570 /* 571 * We need to get hashes here so if there is 572 * a client cert, it can be verified. 573 */ 574 if (!tls1_transcript_hash_value(s, 575 S3I(s)->hs.tls12.cert_verify, 576 sizeof(S3I(s)->hs.tls12.cert_verify), 577 NULL)) { 578 ret = -1; 579 goto end; 580 } 581 } 582 break; 583 584 case SSL3_ST_SR_CERT_VRFY_A: 585 case SSL3_ST_SR_CERT_VRFY_B: 586 if (SSL_is_dtls(s)) 587 s->d1->change_cipher_spec_ok = 1; 588 else 589 s->s3->flags |= SSL3_FLAGS_CCS_OK; 590 591 /* we should decide if we expected this one */ 592 ret = ssl3_get_cert_verify(s); 593 if (ret <= 0) 594 goto end; 595 S3I(s)->hs.state = SSL3_ST_SR_FINISHED_A; 596 s->internal->init_num = 0; 597 break; 598 599 case SSL3_ST_SR_FINISHED_A: 600 case SSL3_ST_SR_FINISHED_B: 601 if (SSL_is_dtls(s)) 602 s->d1->change_cipher_spec_ok = 1; 603 else 604 s->s3->flags |= SSL3_FLAGS_CCS_OK; 605 ret = ssl3_get_finished(s, SSL3_ST_SR_FINISHED_A, 606 SSL3_ST_SR_FINISHED_B); 607 if (ret <= 0) 608 goto end; 609 if (SSL_is_dtls(s)) 610 dtls1_stop_timer(s); 611 if (s->internal->hit) 612 S3I(s)->hs.state = SSL_ST_OK; 613 else if (s->internal->tlsext_ticket_expected) 614 S3I(s)->hs.state = SSL3_ST_SW_SESSION_TICKET_A; 615 else 616 S3I(s)->hs.state = SSL3_ST_SW_CHANGE_A; 617 s->internal->init_num = 0; 618 break; 619 620 case SSL3_ST_SW_SESSION_TICKET_A: 621 case SSL3_ST_SW_SESSION_TICKET_B: 622 ret = ssl3_send_newsession_ticket(s); 623 if (ret <= 0) 624 goto end; 625 S3I(s)->hs.state = SSL3_ST_SW_CHANGE_A; 626 s->internal->init_num = 0; 627 break; 628 629 case SSL3_ST_SW_CERT_STATUS_A: 630 case SSL3_ST_SW_CERT_STATUS_B: 631 ret = ssl3_send_cert_status(s); 632 if (ret <= 0) 633 goto end; 634 S3I(s)->hs.state = SSL3_ST_SW_KEY_EXCH_A; 635 s->internal->init_num = 0; 636 break; 637 638 case SSL3_ST_SW_CHANGE_A: 639 case SSL3_ST_SW_CHANGE_B: 640 ret = ssl3_send_change_cipher_spec(s, 641 SSL3_ST_SW_CHANGE_A, SSL3_ST_SW_CHANGE_B); 642 if (ret <= 0) 643 goto end; 644 S3I(s)->hs.state = SSL3_ST_SW_FINISHED_A; 645 s->internal->init_num = 0; 646 s->session->cipher = S3I(s)->hs.cipher; 647 648 if (!tls1_setup_key_block(s)) { 649 ret = -1; 650 goto end; 651 } 652 if (!tls1_change_write_cipher_state(s)) { 653 ret = -1; 654 goto end; 655 } 656 break; 657 658 case SSL3_ST_SW_FINISHED_A: 659 case SSL3_ST_SW_FINISHED_B: 660 ret = ssl3_send_finished(s, SSL3_ST_SW_FINISHED_A, 661 SSL3_ST_SW_FINISHED_B); 662 if (ret <= 0) 663 goto end; 664 S3I(s)->hs.state = SSL3_ST_SW_FLUSH; 665 if (s->internal->hit) { 666 S3I(s)->hs.tls12.next_state = SSL3_ST_SR_FINISHED_A; 667 tls1_transcript_free(s); 668 } else 669 S3I(s)->hs.tls12.next_state = SSL_ST_OK; 670 s->internal->init_num = 0; 671 break; 672 673 case SSL_ST_OK: 674 /* clean a few things up */ 675 tls1_cleanup_key_block(s); 676 677 if (S3I(s)->handshake_transcript != NULL) { 678 SSLerror(s, ERR_R_INTERNAL_ERROR); 679 ret = -1; 680 goto end; 681 } 682 683 if (!SSL_is_dtls(s)) 684 ssl3_release_init_buffer(s); 685 686 /* remove buffering on output */ 687 ssl_free_wbio_buffer(s); 688 689 s->internal->init_num = 0; 690 691 /* Skipped if we just sent a HelloRequest. */ 692 if (s->internal->renegotiate == 2) { 693 s->internal->renegotiate = 0; 694 s->internal->new_session = 0; 695 696 ssl_update_cache(s, SSL_SESS_CACHE_SERVER); 697 698 s->ctx->internal->stats.sess_accept_good++; 699 /* s->server=1; */ 700 s->internal->handshake_func = ssl3_accept; 701 702 ssl_info_callback(s, SSL_CB_HANDSHAKE_DONE, 1); 703 } 704 705 ret = 1; 706 707 if (SSL_is_dtls(s)) { 708 /* Done handshaking, next message is client hello. */ 709 s->d1->handshake_read_seq = 0; 710 /* Next message is server hello. */ 711 s->d1->handshake_write_seq = 0; 712 s->d1->next_handshake_write_seq = 0; 713 } 714 goto end; 715 /* break; */ 716 717 default: 718 SSLerror(s, SSL_R_UNKNOWN_STATE); 719 ret = -1; 720 goto end; 721 /* break; */ 722 } 723 724 if (!S3I(s)->hs.tls12.reuse_message && !skip) { 725 if (s->internal->debug) { 726 if ((ret = BIO_flush(s->wbio)) <= 0) 727 goto end; 728 } 729 730 731 if (S3I(s)->hs.state != state) { 732 new_state = S3I(s)->hs.state; 733 S3I(s)->hs.state = state; 734 ssl_info_callback(s, SSL_CB_ACCEPT_LOOP, 1); 735 S3I(s)->hs.state = new_state; 736 } 737 } 738 skip = 0; 739 } 740 end: 741 /* BIO_flush(s->wbio); */ 742 s->internal->in_handshake--; 743 ssl_info_callback(s, SSL_CB_ACCEPT_EXIT, ret); 744 745 return (ret); 746 } 747 748 int 749 ssl3_send_hello_request(SSL *s) 750 { 751 CBB cbb, hello; 752 753 memset(&cbb, 0, sizeof(cbb)); 754 755 if (S3I(s)->hs.state == SSL3_ST_SW_HELLO_REQ_A) { 756 if (!ssl3_handshake_msg_start(s, &cbb, &hello, 757 SSL3_MT_HELLO_REQUEST)) 758 goto err; 759 if (!ssl3_handshake_msg_finish(s, &cbb)) 760 goto err; 761 762 S3I(s)->hs.state = SSL3_ST_SW_HELLO_REQ_B; 763 } 764 765 /* SSL3_ST_SW_HELLO_REQ_B */ 766 return (ssl3_handshake_write(s)); 767 768 err: 769 CBB_cleanup(&cbb); 770 771 return (-1); 772 } 773 774 int 775 ssl3_get_client_hello(SSL *s) 776 { 777 CBS cbs, client_random, session_id, cookie, cipher_suites; 778 CBS compression_methods; 779 uint16_t client_version; 780 uint8_t comp_method; 781 int comp_null; 782 int i, j, al, ret, cookie_valid = 0; 783 unsigned long id; 784 SSL_CIPHER *c; 785 STACK_OF(SSL_CIPHER) *ciphers = NULL; 786 unsigned long alg_k; 787 const SSL_METHOD *method; 788 uint16_t shared_version; 789 790 /* 791 * We do this so that we will respond with our native type. 792 * If we are TLSv1 and we get SSLv3, we will respond with TLSv1, 793 * This down switching should be handled by a different method. 794 * If we are SSLv3, we will respond with SSLv3, even if prompted with 795 * TLSv1. 796 */ 797 if (S3I(s)->hs.state == SSL3_ST_SR_CLNT_HELLO_A) 798 S3I(s)->hs.state = SSL3_ST_SR_CLNT_HELLO_B; 799 800 s->internal->first_packet = 1; 801 if ((ret = ssl3_get_message(s, SSL3_ST_SR_CLNT_HELLO_B, 802 SSL3_ST_SR_CLNT_HELLO_C, SSL3_MT_CLIENT_HELLO, 803 SSL3_RT_MAX_PLAIN_LENGTH)) <= 0) 804 return ret; 805 s->internal->first_packet = 0; 806 807 ret = -1; 808 809 if (s->internal->init_num < 0) 810 goto err; 811 812 CBS_init(&cbs, s->internal->init_msg, s->internal->init_num); 813 814 /* Parse client hello up until the extensions (if any). */ 815 if (!CBS_get_u16(&cbs, &client_version)) 816 goto decode_err; 817 if (!CBS_get_bytes(&cbs, &client_random, SSL3_RANDOM_SIZE)) 818 goto decode_err; 819 if (!CBS_get_u8_length_prefixed(&cbs, &session_id)) 820 goto decode_err; 821 if (CBS_len(&session_id) > SSL3_SESSION_ID_SIZE) { 822 al = SSL_AD_ILLEGAL_PARAMETER; 823 SSLerror(s, SSL_R_SSL3_SESSION_ID_TOO_LONG); 824 goto fatal_err; 825 } 826 if (SSL_is_dtls(s)) { 827 if (!CBS_get_u8_length_prefixed(&cbs, &cookie)) 828 goto decode_err; 829 } 830 if (!CBS_get_u16_length_prefixed(&cbs, &cipher_suites)) 831 goto decode_err; 832 if (!CBS_get_u8_length_prefixed(&cbs, &compression_methods)) 833 goto decode_err; 834 835 /* 836 * Use version from inside client hello, not from record header. 837 * (may differ: see RFC 2246, Appendix E, second paragraph) 838 */ 839 if (!ssl_max_shared_version(s, client_version, &shared_version)) { 840 if ((client_version >> 8) == SSL3_VERSION_MAJOR && 841 !tls12_record_layer_write_protected(s->internal->rl)) { 842 /* 843 * Similar to ssl3_get_record, send alert using remote 844 * version number. 845 */ 846 s->version = client_version; 847 } 848 SSLerror(s, SSL_R_WRONG_VERSION_NUMBER); 849 al = SSL_AD_PROTOCOL_VERSION; 850 goto fatal_err; 851 } 852 S3I(s)->hs.peer_legacy_version = client_version; 853 s->version = shared_version; 854 855 S3I(s)->hs.negotiated_tls_version = ssl_tls_version(shared_version); 856 if (S3I(s)->hs.negotiated_tls_version == 0) { 857 SSLerror(s, ERR_R_INTERNAL_ERROR); 858 goto err; 859 } 860 861 if ((method = ssl_get_method(shared_version)) == NULL) { 862 SSLerror(s, ERR_R_INTERNAL_ERROR); 863 goto err; 864 } 865 s->method = method; 866 867 /* 868 * If we require cookies (DTLS) and this ClientHello does not contain 869 * one, just return since we do not want to allocate any memory yet. 870 * So check cookie length... 871 */ 872 if (SSL_is_dtls(s)) { 873 if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) { 874 if (CBS_len(&cookie) == 0) 875 return (1); 876 } 877 } 878 879 if (!CBS_write_bytes(&client_random, s->s3->client_random, 880 sizeof(s->s3->client_random), NULL)) 881 goto err; 882 883 s->internal->hit = 0; 884 885 /* 886 * Versions before 0.9.7 always allow clients to resume sessions in 887 * renegotiation. 0.9.7 and later allow this by default, but optionally 888 * ignore resumption requests with flag 889 * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION (it's a new flag 890 * rather than a change to default behavior so that applications 891 * relying on this for security won't even compile against older 892 * library versions). 893 * 894 * 1.0.1 and later also have a function SSL_renegotiate_abbreviated() 895 * to request renegotiation but not a new session (s->internal->new_session 896 * remains unset): for servers, this essentially just means that the 897 * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION setting will be 898 * ignored. 899 */ 900 if ((s->internal->new_session && (s->internal->options & 901 SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION))) { 902 if (!ssl_get_new_session(s, 1)) 903 goto err; 904 } else { 905 CBS ext_block; 906 907 CBS_dup(&cbs, &ext_block); 908 909 i = ssl_get_prev_session(s, &session_id, &ext_block, &al); 910 if (i == 1) { /* previous session */ 911 s->internal->hit = 1; 912 } else if (i == -1) 913 goto fatal_err; 914 else { 915 /* i == 0 */ 916 if (!ssl_get_new_session(s, 1)) 917 goto err; 918 } 919 } 920 921 if (SSL_is_dtls(s)) { 922 /* 923 * The ClientHello may contain a cookie even if the HelloVerify 924 * message has not been sent - make sure that it does not cause 925 * an overflow. 926 */ 927 if (CBS_len(&cookie) > sizeof(s->d1->rcvd_cookie)) { 928 al = SSL_AD_DECODE_ERROR; 929 SSLerror(s, SSL_R_COOKIE_MISMATCH); 930 goto fatal_err; 931 } 932 933 /* Verify the cookie if appropriate option is set. */ 934 if ((SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) && 935 CBS_len(&cookie) > 0) { 936 size_t cookie_len; 937 938 /* XXX - rcvd_cookie seems to only be used here... */ 939 if (!CBS_write_bytes(&cookie, s->d1->rcvd_cookie, 940 sizeof(s->d1->rcvd_cookie), &cookie_len)) 941 goto err; 942 943 if (s->ctx->internal->app_verify_cookie_cb != NULL) { 944 if (s->ctx->internal->app_verify_cookie_cb(s, 945 s->d1->rcvd_cookie, cookie_len) == 0) { 946 al = SSL_AD_HANDSHAKE_FAILURE; 947 SSLerror(s, SSL_R_COOKIE_MISMATCH); 948 goto fatal_err; 949 } 950 /* else cookie verification succeeded */ 951 /* XXX - can d1->cookie_len > sizeof(rcvd_cookie) ? */ 952 } else if (timingsafe_memcmp(s->d1->rcvd_cookie, 953 s->d1->cookie, s->d1->cookie_len) != 0) { 954 /* default verification */ 955 al = SSL_AD_HANDSHAKE_FAILURE; 956 SSLerror(s, SSL_R_COOKIE_MISMATCH); 957 goto fatal_err; 958 } 959 cookie_valid = 1; 960 } 961 } 962 963 /* XXX - This logic seems wrong... */ 964 if (CBS_len(&cipher_suites) == 0 && CBS_len(&session_id) != 0) { 965 /* we need a cipher if we are not resuming a session */ 966 al = SSL_AD_ILLEGAL_PARAMETER; 967 SSLerror(s, SSL_R_NO_CIPHERS_SPECIFIED); 968 goto fatal_err; 969 } 970 971 if (CBS_len(&cipher_suites) > 0) { 972 if ((ciphers = ssl_bytes_to_cipher_list(s, 973 &cipher_suites)) == NULL) 974 goto err; 975 } 976 977 /* If it is a hit, check that the cipher is in the list */ 978 /* XXX - CBS_len(&cipher_suites) will always be zero here... */ 979 if (s->internal->hit && CBS_len(&cipher_suites) > 0) { 980 j = 0; 981 id = s->session->cipher->id; 982 983 for (i = 0; i < sk_SSL_CIPHER_num(ciphers); i++) { 984 c = sk_SSL_CIPHER_value(ciphers, i); 985 if (c->id == id) { 986 j = 1; 987 break; 988 } 989 } 990 if (j == 0) { 991 /* 992 * We need to have the cipher in the cipher 993 * list if we are asked to reuse it 994 */ 995 al = SSL_AD_ILLEGAL_PARAMETER; 996 SSLerror(s, SSL_R_REQUIRED_CIPHER_MISSING); 997 goto fatal_err; 998 } 999 } 1000 1001 comp_null = 0; 1002 while (CBS_len(&compression_methods) > 0) { 1003 if (!CBS_get_u8(&compression_methods, &comp_method)) 1004 goto decode_err; 1005 if (comp_method == 0) 1006 comp_null = 1; 1007 } 1008 if (comp_null == 0) { 1009 al = SSL_AD_DECODE_ERROR; 1010 SSLerror(s, SSL_R_NO_COMPRESSION_SPECIFIED); 1011 goto fatal_err; 1012 } 1013 1014 if (!tlsext_server_parse(s, SSL_TLSEXT_MSG_CH, &cbs, &al)) { 1015 SSLerror(s, SSL_R_PARSE_TLSEXT); 1016 goto fatal_err; 1017 } 1018 1019 if (CBS_len(&cbs) != 0) 1020 goto decode_err; 1021 1022 if (!S3I(s)->renegotiate_seen && s->internal->renegotiate) { 1023 al = SSL_AD_HANDSHAKE_FAILURE; 1024 SSLerror(s, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED); 1025 goto fatal_err; 1026 } 1027 1028 if (ssl_check_clienthello_tlsext_early(s) <= 0) { 1029 SSLerror(s, SSL_R_CLIENTHELLO_TLSEXT); 1030 goto err; 1031 } 1032 1033 /* 1034 * Check if we want to use external pre-shared secret for this 1035 * handshake for not reused session only. We need to generate 1036 * server_random before calling tls_session_secret_cb in order to allow 1037 * SessionTicket processing to use it in key derivation. 1038 */ 1039 arc4random_buf(s->s3->server_random, SSL3_RANDOM_SIZE); 1040 1041 if (S3I(s)->hs.our_max_tls_version >= TLS1_2_VERSION && 1042 S3I(s)->hs.negotiated_tls_version < S3I(s)->hs.our_max_tls_version) { 1043 /* 1044 * RFC 8446 section 4.1.3. If we are downgrading from TLS 1.3 1045 * we must set the last 8 bytes of the server random to magical 1046 * values to indicate we meant to downgrade. For TLS 1.2 it is 1047 * recommended that we do the same. 1048 */ 1049 size_t index = SSL3_RANDOM_SIZE - sizeof(tls13_downgrade_12); 1050 uint8_t *magic = &s->s3->server_random[index]; 1051 if (S3I(s)->hs.negotiated_tls_version == TLS1_2_VERSION) { 1052 /* Indicate we chose to downgrade to 1.2. */ 1053 memcpy(magic, tls13_downgrade_12, 1054 sizeof(tls13_downgrade_12)); 1055 } else { 1056 /* Indicate we chose to downgrade to 1.1 or lower */ 1057 memcpy(magic, tls13_downgrade_11, 1058 sizeof(tls13_downgrade_11)); 1059 } 1060 } 1061 1062 if (!s->internal->hit && s->internal->tls_session_secret_cb) { 1063 SSL_CIPHER *pref_cipher = NULL; 1064 1065 s->session->master_key_length = sizeof(s->session->master_key); 1066 if (s->internal->tls_session_secret_cb(s, s->session->master_key, 1067 &s->session->master_key_length, ciphers, &pref_cipher, 1068 s->internal->tls_session_secret_cb_arg)) { 1069 s->internal->hit = 1; 1070 s->session->ciphers = ciphers; 1071 s->session->verify_result = X509_V_OK; 1072 1073 ciphers = NULL; 1074 1075 /* check if some cipher was preferred by call back */ 1076 pref_cipher = pref_cipher ? pref_cipher : 1077 ssl3_choose_cipher(s, s->session->ciphers, 1078 SSL_get_ciphers(s)); 1079 if (pref_cipher == NULL) { 1080 al = SSL_AD_HANDSHAKE_FAILURE; 1081 SSLerror(s, SSL_R_NO_SHARED_CIPHER); 1082 goto fatal_err; 1083 } 1084 1085 s->session->cipher = pref_cipher; 1086 1087 sk_SSL_CIPHER_free(s->cipher_list); 1088 s->cipher_list = sk_SSL_CIPHER_dup(s->session->ciphers); 1089 } 1090 } 1091 1092 /* 1093 * Given s->session->ciphers and SSL_get_ciphers, we must 1094 * pick a cipher 1095 */ 1096 1097 if (!s->internal->hit) { 1098 sk_SSL_CIPHER_free(s->session->ciphers); 1099 s->session->ciphers = ciphers; 1100 if (ciphers == NULL) { 1101 al = SSL_AD_ILLEGAL_PARAMETER; 1102 SSLerror(s, SSL_R_NO_CIPHERS_PASSED); 1103 goto fatal_err; 1104 } 1105 ciphers = NULL; 1106 c = ssl3_choose_cipher(s, s->session->ciphers, 1107 SSL_get_ciphers(s)); 1108 1109 if (c == NULL) { 1110 al = SSL_AD_HANDSHAKE_FAILURE; 1111 SSLerror(s, SSL_R_NO_SHARED_CIPHER); 1112 goto fatal_err; 1113 } 1114 S3I(s)->hs.cipher = c; 1115 } else { 1116 S3I(s)->hs.cipher = s->session->cipher; 1117 } 1118 1119 if (!tls1_transcript_hash_init(s)) 1120 goto err; 1121 1122 alg_k = S3I(s)->hs.cipher->algorithm_mkey; 1123 if (!(SSL_USE_SIGALGS(s) || (alg_k & SSL_kGOST)) || 1124 !(s->verify_mode & SSL_VERIFY_PEER)) 1125 tls1_transcript_free(s); 1126 1127 /* 1128 * We now have the following setup. 1129 * client_random 1130 * cipher_list - our prefered list of ciphers 1131 * ciphers - the clients prefered list of ciphers 1132 * compression - basically ignored right now 1133 * ssl version is set - sslv3 1134 * s->session - The ssl session has been setup. 1135 * s->internal->hit - session reuse flag 1136 * s->hs.cipher - the new cipher to use. 1137 */ 1138 1139 /* Handles TLS extensions that we couldn't check earlier */ 1140 if (ssl_check_clienthello_tlsext_late(s) <= 0) { 1141 SSLerror(s, SSL_R_CLIENTHELLO_TLSEXT); 1142 goto err; 1143 } 1144 1145 ret = cookie_valid ? 2 : 1; 1146 1147 if (0) { 1148 decode_err: 1149 al = SSL_AD_DECODE_ERROR; 1150 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 1151 fatal_err: 1152 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1153 } 1154 err: 1155 sk_SSL_CIPHER_free(ciphers); 1156 1157 return (ret); 1158 } 1159 1160 int 1161 ssl3_send_dtls_hello_verify_request(SSL *s) 1162 { 1163 CBB cbb, verify, cookie; 1164 1165 memset(&cbb, 0, sizeof(cbb)); 1166 1167 if (S3I(s)->hs.state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A) { 1168 if (s->ctx->internal->app_gen_cookie_cb == NULL || 1169 s->ctx->internal->app_gen_cookie_cb(s, s->d1->cookie, 1170 &(s->d1->cookie_len)) == 0) { 1171 SSLerror(s, ERR_R_INTERNAL_ERROR); 1172 return 0; 1173 } 1174 1175 /* 1176 * Per RFC 6347 section 4.2.1, the HelloVerifyRequest should 1177 * always contain DTLSv1.0 regardless of the version that is 1178 * going to be negotiated. 1179 */ 1180 if (!ssl3_handshake_msg_start(s, &cbb, &verify, 1181 DTLS1_MT_HELLO_VERIFY_REQUEST)) 1182 goto err; 1183 if (!CBB_add_u16(&verify, DTLS1_VERSION)) 1184 goto err; 1185 if (!CBB_add_u8_length_prefixed(&verify, &cookie)) 1186 goto err; 1187 if (!CBB_add_bytes(&cookie, s->d1->cookie, s->d1->cookie_len)) 1188 goto err; 1189 if (!ssl3_handshake_msg_finish(s, &cbb)) 1190 goto err; 1191 1192 S3I(s)->hs.state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B; 1193 } 1194 1195 /* S3I(s)->hs.state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */ 1196 return (ssl3_handshake_write(s)); 1197 1198 err: 1199 CBB_cleanup(&cbb); 1200 1201 return (-1); 1202 } 1203 1204 int 1205 ssl3_send_server_hello(SSL *s) 1206 { 1207 CBB cbb, server_hello, session_id; 1208 size_t sl; 1209 1210 memset(&cbb, 0, sizeof(cbb)); 1211 1212 if (S3I(s)->hs.state == SSL3_ST_SW_SRVR_HELLO_A) { 1213 if (!ssl3_handshake_msg_start(s, &cbb, &server_hello, 1214 SSL3_MT_SERVER_HELLO)) 1215 goto err; 1216 1217 if (!CBB_add_u16(&server_hello, s->version)) 1218 goto err; 1219 if (!CBB_add_bytes(&server_hello, s->s3->server_random, 1220 sizeof(s->s3->server_random))) 1221 goto err; 1222 1223 /* 1224 * There are several cases for the session ID to send 1225 * back in the server hello: 1226 * 1227 * - For session reuse from the session cache, 1228 * we send back the old session ID. 1229 * - If stateless session reuse (using a session ticket) 1230 * is successful, we send back the client's "session ID" 1231 * (which doesn't actually identify the session). 1232 * - If it is a new session, we send back the new 1233 * session ID. 1234 * - However, if we want the new session to be single-use, 1235 * we send back a 0-length session ID. 1236 * 1237 * s->internal->hit is non-zero in either case of session reuse, 1238 * so the following won't overwrite an ID that we're supposed 1239 * to send back. 1240 */ 1241 if (!(s->ctx->internal->session_cache_mode & SSL_SESS_CACHE_SERVER) 1242 && !s->internal->hit) 1243 s->session->session_id_length = 0; 1244 1245 sl = s->session->session_id_length; 1246 if (sl > sizeof(s->session->session_id)) { 1247 SSLerror(s, ERR_R_INTERNAL_ERROR); 1248 goto err; 1249 } 1250 if (!CBB_add_u8_length_prefixed(&server_hello, &session_id)) 1251 goto err; 1252 if (!CBB_add_bytes(&session_id, s->session->session_id, sl)) 1253 goto err; 1254 1255 /* Cipher suite. */ 1256 if (!CBB_add_u16(&server_hello, 1257 ssl3_cipher_get_value(S3I(s)->hs.cipher))) 1258 goto err; 1259 1260 /* Compression method (null). */ 1261 if (!CBB_add_u8(&server_hello, 0)) 1262 goto err; 1263 1264 /* TLS extensions */ 1265 if (!tlsext_server_build(s, SSL_TLSEXT_MSG_SH, &server_hello)) { 1266 SSLerror(s, ERR_R_INTERNAL_ERROR); 1267 goto err; 1268 } 1269 1270 if (!ssl3_handshake_msg_finish(s, &cbb)) 1271 goto err; 1272 } 1273 1274 /* SSL3_ST_SW_SRVR_HELLO_B */ 1275 return (ssl3_handshake_write(s)); 1276 1277 err: 1278 CBB_cleanup(&cbb); 1279 1280 return (-1); 1281 } 1282 1283 int 1284 ssl3_send_server_done(SSL *s) 1285 { 1286 CBB cbb, done; 1287 1288 memset(&cbb, 0, sizeof(cbb)); 1289 1290 if (S3I(s)->hs.state == SSL3_ST_SW_SRVR_DONE_A) { 1291 if (!ssl3_handshake_msg_start(s, &cbb, &done, 1292 SSL3_MT_SERVER_DONE)) 1293 goto err; 1294 if (!ssl3_handshake_msg_finish(s, &cbb)) 1295 goto err; 1296 1297 S3I(s)->hs.state = SSL3_ST_SW_SRVR_DONE_B; 1298 } 1299 1300 /* SSL3_ST_SW_SRVR_DONE_B */ 1301 return (ssl3_handshake_write(s)); 1302 1303 err: 1304 CBB_cleanup(&cbb); 1305 1306 return (-1); 1307 } 1308 1309 static int 1310 ssl3_send_server_kex_dhe(SSL *s, CBB *cbb) 1311 { 1312 DH *dh = NULL; 1313 int al; 1314 1315 if ((dh = DH_new()) == NULL) 1316 goto err; 1317 1318 if (s->cert->dh_tmp_auto != 0) { 1319 size_t key_bits; 1320 1321 if ((key_bits = ssl_dhe_params_auto_key_bits(s)) == 0) { 1322 al = SSL_AD_INTERNAL_ERROR; 1323 SSLerror(s, ERR_R_INTERNAL_ERROR); 1324 goto fatal_err; 1325 } 1326 1327 if (!ssl_kex_generate_dhe_params_auto(dh, key_bits)) 1328 goto err; 1329 } else { 1330 DH *dh_params = s->cert->dh_tmp; 1331 1332 if (dh_params == NULL && s->cert->dh_tmp_cb != NULL) 1333 dh_params = s->cert->dh_tmp_cb(s, 0, 1334 SSL_C_PKEYLENGTH(S3I(s)->hs.cipher)); 1335 1336 if (dh_params == NULL) { 1337 al = SSL_AD_HANDSHAKE_FAILURE; 1338 SSLerror(s, SSL_R_MISSING_TMP_DH_KEY); 1339 goto fatal_err; 1340 } 1341 1342 if (!ssl_kex_generate_dhe(dh, dh_params)) 1343 goto err; 1344 } 1345 1346 if (!ssl_kex_params_dhe(dh, cbb)) 1347 goto err; 1348 if (!ssl_kex_public_dhe(dh, cbb)) 1349 goto err; 1350 1351 if (S3I(s)->tmp.dh != NULL) { 1352 SSLerror(s, ERR_R_INTERNAL_ERROR); 1353 goto err; 1354 } 1355 S3I(s)->tmp.dh = dh; 1356 1357 return 1; 1358 1359 fatal_err: 1360 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1361 err: 1362 DH_free(dh); 1363 1364 return -1; 1365 } 1366 1367 static int 1368 ssl3_send_server_kex_ecdhe_ecp(SSL *s, int nid, CBB *cbb) 1369 { 1370 uint16_t curve_id; 1371 EC_KEY *ecdh; 1372 CBB ecpoint; 1373 int al; 1374 1375 /* 1376 * Only named curves are supported in ECDH ephemeral key exchanges. 1377 * For supported named curves, curve_id is non-zero. 1378 */ 1379 if ((curve_id = tls1_ec_nid2curve_id(nid)) == 0) { 1380 SSLerror(s, SSL_R_UNSUPPORTED_ELLIPTIC_CURVE); 1381 goto err; 1382 } 1383 1384 if (S3I(s)->tmp.ecdh != NULL) { 1385 SSLerror(s, ERR_R_INTERNAL_ERROR); 1386 goto err; 1387 } 1388 1389 if ((S3I(s)->tmp.ecdh = EC_KEY_new()) == NULL) { 1390 al = SSL_AD_HANDSHAKE_FAILURE; 1391 SSLerror(s, SSL_R_MISSING_TMP_ECDH_KEY); 1392 goto fatal_err; 1393 } 1394 S3I(s)->tmp.ecdh_nid = nid; 1395 ecdh = S3I(s)->tmp.ecdh; 1396 1397 if (!ssl_kex_generate_ecdhe_ecp(ecdh, nid)) 1398 goto err; 1399 1400 /* 1401 * Encode the public key. 1402 * 1403 * Only named curves are supported in ECDH ephemeral key exchanges. 1404 * In this case the ServerKeyExchange message has: 1405 * [1 byte CurveType], [2 byte CurveName] 1406 * [1 byte length of encoded point], followed by 1407 * the actual encoded point itself. 1408 */ 1409 if (!CBB_add_u8(cbb, NAMED_CURVE_TYPE)) 1410 goto err; 1411 if (!CBB_add_u16(cbb, curve_id)) 1412 goto err; 1413 if (!CBB_add_u8_length_prefixed(cbb, &ecpoint)) 1414 goto err; 1415 if (!ssl_kex_public_ecdhe_ecp(ecdh, &ecpoint)) 1416 goto err; 1417 if (!CBB_flush(cbb)) 1418 goto err; 1419 1420 return (1); 1421 1422 fatal_err: 1423 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1424 err: 1425 return (-1); 1426 } 1427 1428 static int 1429 ssl3_send_server_kex_ecdhe_ecx(SSL *s, int nid, CBB *cbb) 1430 { 1431 uint8_t *public_key = NULL, *private_key = NULL; 1432 uint16_t curve_id; 1433 CBB ecpoint; 1434 int ret = -1; 1435 1436 /* Generate an X25519 key pair. */ 1437 if (S3I(s)->tmp.x25519 != NULL) { 1438 SSLerror(s, ERR_R_INTERNAL_ERROR); 1439 goto err; 1440 } 1441 if ((private_key = malloc(X25519_KEY_LENGTH)) == NULL) 1442 goto err; 1443 if ((public_key = malloc(X25519_KEY_LENGTH)) == NULL) 1444 goto err; 1445 X25519_keypair(public_key, private_key); 1446 1447 /* Serialize public key. */ 1448 if ((curve_id = tls1_ec_nid2curve_id(nid)) == 0) { 1449 SSLerror(s, SSL_R_UNSUPPORTED_ELLIPTIC_CURVE); 1450 goto err; 1451 } 1452 1453 if (!CBB_add_u8(cbb, NAMED_CURVE_TYPE)) 1454 goto err; 1455 if (!CBB_add_u16(cbb, curve_id)) 1456 goto err; 1457 if (!CBB_add_u8_length_prefixed(cbb, &ecpoint)) 1458 goto err; 1459 if (!CBB_add_bytes(&ecpoint, public_key, X25519_KEY_LENGTH)) 1460 goto err; 1461 if (!CBB_flush(cbb)) 1462 goto err; 1463 1464 S3I(s)->tmp.x25519 = private_key; 1465 private_key = NULL; 1466 ret = 1; 1467 1468 err: 1469 free(public_key); 1470 freezero(private_key, X25519_KEY_LENGTH); 1471 1472 return (ret); 1473 } 1474 1475 static int 1476 ssl3_send_server_kex_ecdhe(SSL *s, CBB *cbb) 1477 { 1478 int nid; 1479 1480 nid = tls1_get_shared_curve(s); 1481 1482 if (nid == NID_X25519) 1483 return ssl3_send_server_kex_ecdhe_ecx(s, nid, cbb); 1484 1485 return ssl3_send_server_kex_ecdhe_ecp(s, nid, cbb); 1486 } 1487 1488 int 1489 ssl3_send_server_key_exchange(SSL *s) 1490 { 1491 CBB cbb, cbb_params, cbb_signature, server_kex; 1492 const struct ssl_sigalg *sigalg = NULL; 1493 unsigned char *signature = NULL; 1494 size_t signature_len = 0; 1495 unsigned char *params = NULL; 1496 size_t params_len; 1497 const EVP_MD *md = NULL; 1498 unsigned long type; 1499 EVP_MD_CTX md_ctx; 1500 EVP_PKEY_CTX *pctx; 1501 EVP_PKEY *pkey; 1502 int al; 1503 1504 memset(&cbb, 0, sizeof(cbb)); 1505 memset(&cbb_params, 0, sizeof(cbb_params)); 1506 1507 EVP_MD_CTX_init(&md_ctx); 1508 1509 if (S3I(s)->hs.state == SSL3_ST_SW_KEY_EXCH_A) { 1510 1511 if (!ssl3_handshake_msg_start(s, &cbb, &server_kex, 1512 SSL3_MT_SERVER_KEY_EXCHANGE)) 1513 goto err; 1514 1515 if (!CBB_init(&cbb_params, 0)) 1516 goto err; 1517 1518 type = S3I(s)->hs.cipher->algorithm_mkey; 1519 if (type & SSL_kDHE) { 1520 if (ssl3_send_server_kex_dhe(s, &cbb_params) != 1) 1521 goto err; 1522 } else if (type & SSL_kECDHE) { 1523 if (ssl3_send_server_kex_ecdhe(s, &cbb_params) != 1) 1524 goto err; 1525 } else { 1526 al = SSL_AD_HANDSHAKE_FAILURE; 1527 SSLerror(s, SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE); 1528 goto fatal_err; 1529 } 1530 1531 if (!CBB_finish(&cbb_params, ¶ms, ¶ms_len)) 1532 goto err; 1533 1534 if (!CBB_add_bytes(&server_kex, params, params_len)) 1535 goto err; 1536 1537 /* Add signature unless anonymous. */ 1538 if (!(S3I(s)->hs.cipher->algorithm_auth & SSL_aNULL)) { 1539 if ((pkey = ssl_get_sign_pkey(s, S3I(s)->hs.cipher, 1540 &md, &sigalg)) == NULL) { 1541 al = SSL_AD_DECODE_ERROR; 1542 goto fatal_err; 1543 } 1544 S3I(s)->hs.our_sigalg = sigalg; 1545 1546 /* Send signature algorithm. */ 1547 if (SSL_USE_SIGALGS(s)) { 1548 if (!CBB_add_u16(&server_kex, sigalg->value)) { 1549 al = SSL_AD_INTERNAL_ERROR; 1550 SSLerror(s, ERR_R_INTERNAL_ERROR); 1551 goto fatal_err; 1552 } 1553 } 1554 1555 if (!EVP_DigestSignInit(&md_ctx, &pctx, md, NULL, pkey)) { 1556 SSLerror(s, ERR_R_EVP_LIB); 1557 goto err; 1558 } 1559 if ((sigalg->flags & SIGALG_FLAG_RSA_PSS) && 1560 (!EVP_PKEY_CTX_set_rsa_padding(pctx, 1561 RSA_PKCS1_PSS_PADDING) || 1562 !EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, -1))) { 1563 SSLerror(s, ERR_R_EVP_LIB); 1564 goto err; 1565 } 1566 if (!EVP_DigestSignUpdate(&md_ctx, s->s3->client_random, 1567 SSL3_RANDOM_SIZE)) { 1568 SSLerror(s, ERR_R_EVP_LIB); 1569 goto err; 1570 } 1571 if (!EVP_DigestSignUpdate(&md_ctx, s->s3->server_random, 1572 SSL3_RANDOM_SIZE)) { 1573 SSLerror(s, ERR_R_EVP_LIB); 1574 goto err; 1575 } 1576 if (!EVP_DigestSignUpdate(&md_ctx, params, params_len)) { 1577 SSLerror(s, ERR_R_EVP_LIB); 1578 goto err; 1579 } 1580 if (!EVP_DigestSignFinal(&md_ctx, NULL, &signature_len) || 1581 !signature_len) { 1582 SSLerror(s, ERR_R_EVP_LIB); 1583 goto err; 1584 } 1585 if ((signature = calloc(1, signature_len)) == NULL) { 1586 SSLerror(s, ERR_R_MALLOC_FAILURE); 1587 goto err; 1588 } 1589 if (!EVP_DigestSignFinal(&md_ctx, signature, &signature_len)) { 1590 SSLerror(s, ERR_R_EVP_LIB); 1591 goto err; 1592 } 1593 1594 if (!CBB_add_u16_length_prefixed(&server_kex, 1595 &cbb_signature)) 1596 goto err; 1597 if (!CBB_add_bytes(&cbb_signature, signature, 1598 signature_len)) 1599 goto err; 1600 } 1601 1602 if (!ssl3_handshake_msg_finish(s, &cbb)) 1603 goto err; 1604 1605 S3I(s)->hs.state = SSL3_ST_SW_KEY_EXCH_B; 1606 } 1607 1608 EVP_MD_CTX_cleanup(&md_ctx); 1609 free(params); 1610 free(signature); 1611 1612 return (ssl3_handshake_write(s)); 1613 1614 fatal_err: 1615 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1616 err: 1617 CBB_cleanup(&cbb_params); 1618 CBB_cleanup(&cbb); 1619 EVP_MD_CTX_cleanup(&md_ctx); 1620 free(params); 1621 free(signature); 1622 1623 return (-1); 1624 } 1625 1626 int 1627 ssl3_send_certificate_request(SSL *s) 1628 { 1629 CBB cbb, cert_request, cert_types, sigalgs, cert_auth, dn; 1630 STACK_OF(X509_NAME) *sk = NULL; 1631 X509_NAME *name; 1632 int i; 1633 1634 /* 1635 * Certificate Request - RFC 5246 section 7.4.4. 1636 */ 1637 1638 memset(&cbb, 0, sizeof(cbb)); 1639 1640 if (S3I(s)->hs.state == SSL3_ST_SW_CERT_REQ_A) { 1641 if (!ssl3_handshake_msg_start(s, &cbb, &cert_request, 1642 SSL3_MT_CERTIFICATE_REQUEST)) 1643 goto err; 1644 1645 if (!CBB_add_u8_length_prefixed(&cert_request, &cert_types)) 1646 goto err; 1647 if (!ssl3_get_req_cert_types(s, &cert_types)) 1648 goto err; 1649 1650 if (SSL_USE_SIGALGS(s)) { 1651 if (!CBB_add_u16_length_prefixed(&cert_request, 1652 &sigalgs)) 1653 goto err; 1654 if (!ssl_sigalgs_build( 1655 S3I(s)->hs.negotiated_tls_version, &sigalgs)) 1656 goto err; 1657 } 1658 1659 if (!CBB_add_u16_length_prefixed(&cert_request, &cert_auth)) 1660 goto err; 1661 1662 sk = SSL_get_client_CA_list(s); 1663 for (i = 0; i < sk_X509_NAME_num(sk); i++) { 1664 unsigned char *name_data; 1665 size_t name_len; 1666 1667 name = sk_X509_NAME_value(sk, i); 1668 name_len = i2d_X509_NAME(name, NULL); 1669 1670 if (!CBB_add_u16_length_prefixed(&cert_auth, &dn)) 1671 goto err; 1672 if (!CBB_add_space(&dn, &name_data, name_len)) 1673 goto err; 1674 if (i2d_X509_NAME(name, &name_data) != name_len) 1675 goto err; 1676 } 1677 1678 if (!ssl3_handshake_msg_finish(s, &cbb)) 1679 goto err; 1680 1681 S3I(s)->hs.state = SSL3_ST_SW_CERT_REQ_B; 1682 } 1683 1684 /* SSL3_ST_SW_CERT_REQ_B */ 1685 return (ssl3_handshake_write(s)); 1686 1687 err: 1688 CBB_cleanup(&cbb); 1689 1690 return (-1); 1691 } 1692 1693 static int 1694 ssl3_get_client_kex_rsa(SSL *s, CBS *cbs) 1695 { 1696 unsigned char fakekey[SSL_MAX_MASTER_KEY_LENGTH]; 1697 unsigned char *pms = NULL; 1698 unsigned char *p; 1699 size_t pms_len = 0; 1700 EVP_PKEY *pkey = NULL; 1701 RSA *rsa = NULL; 1702 CBS enc_pms; 1703 int decrypt_len; 1704 int al = -1; 1705 1706 arc4random_buf(fakekey, sizeof(fakekey)); 1707 1708 fakekey[0] = S3I(s)->hs.peer_legacy_version >> 8; 1709 fakekey[1] = S3I(s)->hs.peer_legacy_version & 0xff; 1710 1711 pkey = s->cert->pkeys[SSL_PKEY_RSA].privatekey; 1712 if (pkey == NULL || (rsa = EVP_PKEY_get0_RSA(pkey)) == NULL) { 1713 al = SSL_AD_HANDSHAKE_FAILURE; 1714 SSLerror(s, SSL_R_MISSING_RSA_CERTIFICATE); 1715 goto fatal_err; 1716 } 1717 1718 pms_len = RSA_size(rsa); 1719 if (pms_len < SSL_MAX_MASTER_KEY_LENGTH) 1720 goto err; 1721 if ((pms = malloc(pms_len)) == NULL) 1722 goto err; 1723 p = pms; 1724 1725 if (!CBS_get_u16_length_prefixed(cbs, &enc_pms)) 1726 goto decode_err; 1727 if (CBS_len(cbs) != 0 || CBS_len(&enc_pms) != RSA_size(rsa)) { 1728 SSLerror(s, SSL_R_TLS_RSA_ENCRYPTED_VALUE_LENGTH_IS_WRONG); 1729 goto err; 1730 } 1731 1732 decrypt_len = RSA_private_decrypt(CBS_len(&enc_pms), CBS_data(&enc_pms), 1733 pms, rsa, RSA_PKCS1_PADDING); 1734 1735 ERR_clear_error(); 1736 1737 if (decrypt_len != SSL_MAX_MASTER_KEY_LENGTH) { 1738 al = SSL_AD_DECODE_ERROR; 1739 /* SSLerror(s, SSL_R_BAD_RSA_DECRYPT); */ 1740 } 1741 1742 if ((al == -1) && !((pms[0] == (S3I(s)->hs.peer_legacy_version >> 8)) && 1743 (pms[1] == (S3I(s)->hs.peer_legacy_version & 0xff)))) { 1744 /* 1745 * The premaster secret must contain the same version number 1746 * as the ClientHello to detect version rollback attacks 1747 * (strangely, the protocol does not offer such protection for 1748 * DH ciphersuites). 1749 * 1750 * The Klima-Pokorny-Rosa extension of Bleichenbacher's attack 1751 * (http://eprint.iacr.org/2003/052/) exploits the version 1752 * number check as a "bad version oracle" -- an alert would 1753 * reveal that the plaintext corresponding to some ciphertext 1754 * made up by the adversary is properly formatted except that 1755 * the version number is wrong. To avoid such attacks, we should 1756 * treat this just like any other decryption error. 1757 */ 1758 al = SSL_AD_DECODE_ERROR; 1759 /* SSLerror(s, SSL_R_BAD_PROTOCOL_VERSION_NUMBER); */ 1760 } 1761 1762 if (al != -1) { 1763 /* 1764 * Some decryption failure -- use random value instead 1765 * as countermeasure against Bleichenbacher's attack 1766 * on PKCS #1 v1.5 RSA padding (see RFC 2246, 1767 * section 7.4.7.1). 1768 */ 1769 p = fakekey; 1770 } 1771 1772 if (!tls12_derive_master_secret(s, p, SSL_MAX_MASTER_KEY_LENGTH)) 1773 goto err; 1774 1775 freezero(pms, pms_len); 1776 1777 return (1); 1778 1779 decode_err: 1780 al = SSL_AD_DECODE_ERROR; 1781 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 1782 fatal_err: 1783 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1784 err: 1785 freezero(pms, pms_len); 1786 1787 return (-1); 1788 } 1789 1790 static int 1791 ssl3_get_client_kex_dhe(SSL *s, CBS *cbs) 1792 { 1793 DH *dh_clnt = NULL; 1794 DH *dh_srvr; 1795 int invalid_key; 1796 uint8_t *key = NULL; 1797 size_t key_len = 0; 1798 int ret = -1; 1799 1800 if ((dh_srvr = S3I(s)->tmp.dh) == NULL) { 1801 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); 1802 SSLerror(s, SSL_R_MISSING_TMP_DH_KEY); 1803 goto err; 1804 } 1805 1806 if ((dh_clnt = DHparams_dup(dh_srvr)) == NULL) 1807 goto err; 1808 1809 if (!ssl_kex_peer_public_dhe(dh_clnt, cbs, &invalid_key)) { 1810 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); 1811 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 1812 goto err; 1813 } 1814 if (invalid_key) { 1815 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); 1816 SSLerror(s, SSL_R_BAD_DH_PUB_KEY_LENGTH); 1817 goto err; 1818 } 1819 1820 if (!ssl_kex_derive_dhe(dh_srvr, dh_clnt, &key, &key_len)) 1821 goto err; 1822 1823 if (!tls12_derive_master_secret(s, key, key_len)) 1824 goto err; 1825 1826 DH_free(S3I(s)->tmp.dh); 1827 S3I(s)->tmp.dh = NULL; 1828 1829 ret = 1; 1830 1831 err: 1832 freezero(key, key_len); 1833 DH_free(dh_clnt); 1834 1835 return ret; 1836 } 1837 1838 static int 1839 ssl3_get_client_kex_ecdhe_ecp(SSL *s, CBS *cbs) 1840 { 1841 uint8_t *key = NULL; 1842 size_t key_len = 0; 1843 EC_KEY *ecdh_peer = NULL; 1844 EC_KEY *ecdh; 1845 CBS public; 1846 int ret = -1; 1847 1848 /* 1849 * Use the ephemeral values we saved when generating the 1850 * ServerKeyExchange message. 1851 */ 1852 if ((ecdh = S3I(s)->tmp.ecdh) == NULL) { 1853 SSLerror(s, ERR_R_INTERNAL_ERROR); 1854 goto err; 1855 } 1856 1857 /* 1858 * Get client's public key from encoded point in the ClientKeyExchange 1859 * message. 1860 */ 1861 if (!CBS_get_u8_length_prefixed(cbs, &public)) 1862 goto err; 1863 if (CBS_len(cbs) != 0) 1864 goto err; 1865 1866 if ((ecdh_peer = EC_KEY_new()) == NULL) 1867 goto err; 1868 1869 if (!ssl_kex_peer_public_ecdhe_ecp(ecdh_peer, S3I(s)->tmp.ecdh_nid, 1870 &public)) 1871 goto err; 1872 1873 /* Derive the shared secret and compute master secret. */ 1874 if (!ssl_kex_derive_ecdhe_ecp(ecdh, ecdh_peer, &key, &key_len)) 1875 goto err; 1876 if (!tls12_derive_master_secret(s, key, key_len)) 1877 goto err; 1878 1879 EC_KEY_free(S3I(s)->tmp.ecdh); 1880 S3I(s)->tmp.ecdh = NULL; 1881 S3I(s)->tmp.ecdh_nid = NID_undef; 1882 1883 ret = 1; 1884 1885 err: 1886 freezero(key, key_len); 1887 EC_KEY_free(ecdh_peer); 1888 1889 return (ret); 1890 } 1891 1892 static int 1893 ssl3_get_client_kex_ecdhe_ecx(SSL *s, CBS *cbs) 1894 { 1895 uint8_t *shared_key = NULL; 1896 CBS ecpoint; 1897 int ret = -1; 1898 1899 if (!CBS_get_u8_length_prefixed(cbs, &ecpoint)) 1900 goto err; 1901 if (CBS_len(cbs) != 0) 1902 goto err; 1903 if (CBS_len(&ecpoint) != X25519_KEY_LENGTH) 1904 goto err; 1905 1906 if ((shared_key = malloc(X25519_KEY_LENGTH)) == NULL) 1907 goto err; 1908 if (!X25519(shared_key, S3I(s)->tmp.x25519, CBS_data(&ecpoint))) 1909 goto err; 1910 1911 freezero(S3I(s)->tmp.x25519, X25519_KEY_LENGTH); 1912 S3I(s)->tmp.x25519 = NULL; 1913 1914 if (!tls12_derive_master_secret(s, shared_key, X25519_KEY_LENGTH)) 1915 goto err; 1916 1917 ret = 1; 1918 1919 err: 1920 freezero(shared_key, X25519_KEY_LENGTH); 1921 1922 return (ret); 1923 } 1924 1925 static int 1926 ssl3_get_client_kex_ecdhe(SSL *s, CBS *cbs) 1927 { 1928 if (S3I(s)->tmp.x25519 != NULL) 1929 return ssl3_get_client_kex_ecdhe_ecx(s, cbs); 1930 1931 return ssl3_get_client_kex_ecdhe_ecp(s, cbs); 1932 } 1933 1934 static int 1935 ssl3_get_client_kex_gost(SSL *s, CBS *cbs) 1936 { 1937 EVP_PKEY_CTX *pkey_ctx; 1938 EVP_PKEY *client_pub_pkey = NULL, *pk = NULL; 1939 unsigned char premaster_secret[32]; 1940 unsigned long alg_a; 1941 size_t outlen = 32; 1942 CBS gostblob; 1943 int al; 1944 int ret = 0; 1945 1946 /* Get our certificate private key*/ 1947 alg_a = S3I(s)->hs.cipher->algorithm_auth; 1948 if (alg_a & SSL_aGOST01) 1949 pk = s->cert->pkeys[SSL_PKEY_GOST01].privatekey; 1950 1951 if ((pkey_ctx = EVP_PKEY_CTX_new(pk, NULL)) == NULL) 1952 goto err; 1953 if (EVP_PKEY_decrypt_init(pkey_ctx) <= 0) 1954 goto gerr; 1955 1956 /* 1957 * If client certificate is present and is of the same type, 1958 * maybe use it for key exchange. 1959 * Don't mind errors from EVP_PKEY_derive_set_peer, because 1960 * it is completely valid to use a client certificate for 1961 * authorization only. 1962 */ 1963 if ((client_pub_pkey = X509_get_pubkey(s->session->peer)) != NULL) { 1964 if (EVP_PKEY_derive_set_peer(pkey_ctx, 1965 client_pub_pkey) <= 0) 1966 ERR_clear_error(); 1967 } 1968 1969 /* Decrypt session key */ 1970 if (!CBS_get_asn1(cbs, &gostblob, CBS_ASN1_SEQUENCE)) 1971 goto decode_err; 1972 if (CBS_len(cbs) != 0) 1973 goto decode_err; 1974 if (EVP_PKEY_decrypt(pkey_ctx, premaster_secret, &outlen, 1975 CBS_data(&gostblob), CBS_len(&gostblob)) <= 0) { 1976 SSLerror(s, SSL_R_DECRYPTION_FAILED); 1977 goto gerr; 1978 } 1979 1980 if (!tls12_derive_master_secret(s, premaster_secret, 32)) 1981 goto err; 1982 1983 /* Check if pubkey from client certificate was used */ 1984 if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, -1, 1985 EVP_PKEY_CTRL_PEER_KEY, 2, NULL) > 0) 1986 ret = 2; 1987 else 1988 ret = 1; 1989 gerr: 1990 EVP_PKEY_free(client_pub_pkey); 1991 EVP_PKEY_CTX_free(pkey_ctx); 1992 if (ret) 1993 return (ret); 1994 else 1995 goto err; 1996 1997 decode_err: 1998 al = SSL_AD_DECODE_ERROR; 1999 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 2000 ssl3_send_alert(s, SSL3_AL_FATAL, al); 2001 err: 2002 return (-1); 2003 } 2004 2005 int 2006 ssl3_get_client_key_exchange(SSL *s) 2007 { 2008 unsigned long alg_k; 2009 int al, ret; 2010 CBS cbs; 2011 2012 /* 2048 maxlen is a guess. How long a key does that permit? */ 2013 if ((ret = ssl3_get_message(s, SSL3_ST_SR_KEY_EXCH_A, 2014 SSL3_ST_SR_KEY_EXCH_B, SSL3_MT_CLIENT_KEY_EXCHANGE, 2048)) <= 0) 2015 return ret; 2016 2017 if (s->internal->init_num < 0) 2018 goto err; 2019 2020 CBS_init(&cbs, s->internal->init_msg, s->internal->init_num); 2021 2022 alg_k = S3I(s)->hs.cipher->algorithm_mkey; 2023 2024 if (alg_k & SSL_kRSA) { 2025 if (ssl3_get_client_kex_rsa(s, &cbs) != 1) 2026 goto err; 2027 } else if (alg_k & SSL_kDHE) { 2028 if (ssl3_get_client_kex_dhe(s, &cbs) != 1) 2029 goto err; 2030 } else if (alg_k & SSL_kECDHE) { 2031 if (ssl3_get_client_kex_ecdhe(s, &cbs) != 1) 2032 goto err; 2033 } else if (alg_k & SSL_kGOST) { 2034 if (ssl3_get_client_kex_gost(s, &cbs) != 1) 2035 goto err; 2036 } else { 2037 al = SSL_AD_HANDSHAKE_FAILURE; 2038 SSLerror(s, SSL_R_UNKNOWN_CIPHER_TYPE); 2039 goto fatal_err; 2040 } 2041 2042 if (CBS_len(&cbs) != 0) { 2043 al = SSL_AD_DECODE_ERROR; 2044 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 2045 goto fatal_err; 2046 } 2047 2048 return (1); 2049 2050 fatal_err: 2051 ssl3_send_alert(s, SSL3_AL_FATAL, al); 2052 err: 2053 return (-1); 2054 } 2055 2056 int 2057 ssl3_get_cert_verify(SSL *s) 2058 { 2059 CBS cbs, signature; 2060 const struct ssl_sigalg *sigalg = NULL; 2061 uint16_t sigalg_value = SIGALG_NONE; 2062 EVP_PKEY *pkey = NULL; 2063 X509 *peer = NULL; 2064 EVP_MD_CTX mctx; 2065 int al, verify; 2066 const unsigned char *hdata; 2067 size_t hdatalen; 2068 int type = 0; 2069 int ret; 2070 2071 EVP_MD_CTX_init(&mctx); 2072 2073 if ((ret = ssl3_get_message(s, SSL3_ST_SR_CERT_VRFY_A, 2074 SSL3_ST_SR_CERT_VRFY_B, -1, SSL3_RT_MAX_PLAIN_LENGTH)) <= 0) 2075 return ret; 2076 2077 ret = 0; 2078 2079 if (s->internal->init_num < 0) 2080 goto err; 2081 2082 CBS_init(&cbs, s->internal->init_msg, s->internal->init_num); 2083 2084 if (s->session->peer != NULL) { 2085 peer = s->session->peer; 2086 pkey = X509_get_pubkey(peer); 2087 type = X509_certificate_type(peer, pkey); 2088 } 2089 2090 if (S3I(s)->hs.tls12.message_type != SSL3_MT_CERTIFICATE_VERIFY) { 2091 S3I(s)->hs.tls12.reuse_message = 1; 2092 if (peer != NULL) { 2093 al = SSL_AD_UNEXPECTED_MESSAGE; 2094 SSLerror(s, SSL_R_MISSING_VERIFY_MESSAGE); 2095 goto fatal_err; 2096 } 2097 ret = 1; 2098 goto end; 2099 } 2100 2101 if (peer == NULL) { 2102 SSLerror(s, SSL_R_NO_CLIENT_CERT_RECEIVED); 2103 al = SSL_AD_UNEXPECTED_MESSAGE; 2104 goto fatal_err; 2105 } 2106 2107 if (!(type & EVP_PKT_SIGN)) { 2108 SSLerror(s, SSL_R_SIGNATURE_FOR_NON_SIGNING_CERTIFICATE); 2109 al = SSL_AD_ILLEGAL_PARAMETER; 2110 goto fatal_err; 2111 } 2112 2113 if (S3I(s)->change_cipher_spec) { 2114 SSLerror(s, SSL_R_CCS_RECEIVED_EARLY); 2115 al = SSL_AD_UNEXPECTED_MESSAGE; 2116 goto fatal_err; 2117 } 2118 2119 if (SSL_USE_SIGALGS(s)) { 2120 if (!CBS_get_u16(&cbs, &sigalg_value)) 2121 goto decode_err; 2122 } 2123 if (!CBS_get_u16_length_prefixed(&cbs, &signature)) 2124 goto err; 2125 if (CBS_len(&cbs) != 0) { 2126 al = SSL_AD_DECODE_ERROR; 2127 SSLerror(s, SSL_R_EXTRA_DATA_IN_MESSAGE); 2128 goto fatal_err; 2129 } 2130 2131 if (CBS_len(&signature) > EVP_PKEY_size(pkey)) { 2132 SSLerror(s, SSL_R_WRONG_SIGNATURE_SIZE); 2133 al = SSL_AD_DECODE_ERROR; 2134 goto fatal_err; 2135 } 2136 2137 if ((sigalg = ssl_sigalg_for_peer(s, pkey, 2138 sigalg_value)) == NULL) { 2139 al = SSL_AD_DECODE_ERROR; 2140 goto fatal_err; 2141 } 2142 S3I(s)->hs.peer_sigalg = sigalg; 2143 2144 if (SSL_USE_SIGALGS(s)) { 2145 EVP_PKEY_CTX *pctx; 2146 2147 if (!tls1_transcript_data(s, &hdata, &hdatalen)) { 2148 SSLerror(s, ERR_R_INTERNAL_ERROR); 2149 al = SSL_AD_INTERNAL_ERROR; 2150 goto fatal_err; 2151 } 2152 if (!EVP_DigestVerifyInit(&mctx, &pctx, sigalg->md(), 2153 NULL, pkey)) { 2154 SSLerror(s, ERR_R_EVP_LIB); 2155 al = SSL_AD_INTERNAL_ERROR; 2156 goto fatal_err; 2157 } 2158 if ((sigalg->flags & SIGALG_FLAG_RSA_PSS) && 2159 (!EVP_PKEY_CTX_set_rsa_padding(pctx, 2160 RSA_PKCS1_PSS_PADDING) || 2161 !EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, -1))) { 2162 al = SSL_AD_INTERNAL_ERROR; 2163 goto fatal_err; 2164 } 2165 if (sigalg->key_type == EVP_PKEY_GOSTR01 && 2166 EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_VERIFY, 2167 EVP_PKEY_CTRL_GOST_SIG_FORMAT, GOST_SIG_FORMAT_RS_LE, 2168 NULL) <= 0) { 2169 al = SSL_AD_INTERNAL_ERROR; 2170 goto fatal_err; 2171 } 2172 if (!EVP_DigestVerifyUpdate(&mctx, hdata, hdatalen)) { 2173 SSLerror(s, ERR_R_EVP_LIB); 2174 al = SSL_AD_INTERNAL_ERROR; 2175 goto fatal_err; 2176 } 2177 if (EVP_DigestVerifyFinal(&mctx, CBS_data(&signature), 2178 CBS_len(&signature)) <= 0) { 2179 al = SSL_AD_DECRYPT_ERROR; 2180 SSLerror(s, SSL_R_BAD_SIGNATURE); 2181 goto fatal_err; 2182 } 2183 } else if (EVP_PKEY_id(pkey) == EVP_PKEY_RSA) { 2184 RSA *rsa; 2185 2186 if ((rsa = EVP_PKEY_get0_RSA(pkey)) == NULL) { 2187 al = SSL_AD_INTERNAL_ERROR; 2188 SSLerror(s, ERR_R_EVP_LIB); 2189 goto fatal_err; 2190 } 2191 verify = RSA_verify(NID_md5_sha1, S3I(s)->hs.tls12.cert_verify, 2192 MD5_DIGEST_LENGTH + SHA_DIGEST_LENGTH, CBS_data(&signature), 2193 CBS_len(&signature), rsa); 2194 if (verify < 0) { 2195 al = SSL_AD_DECRYPT_ERROR; 2196 SSLerror(s, SSL_R_BAD_RSA_DECRYPT); 2197 goto fatal_err; 2198 } 2199 if (verify == 0) { 2200 al = SSL_AD_DECRYPT_ERROR; 2201 SSLerror(s, SSL_R_BAD_RSA_SIGNATURE); 2202 goto fatal_err; 2203 } 2204 } else if (EVP_PKEY_id(pkey) == EVP_PKEY_EC) { 2205 EC_KEY *eckey; 2206 2207 if ((eckey = EVP_PKEY_get0_EC_KEY(pkey)) == NULL) { 2208 al = SSL_AD_INTERNAL_ERROR; 2209 SSLerror(s, ERR_R_EVP_LIB); 2210 goto fatal_err; 2211 } 2212 verify = ECDSA_verify(0, 2213 &(S3I(s)->hs.tls12.cert_verify[MD5_DIGEST_LENGTH]), 2214 SHA_DIGEST_LENGTH, CBS_data(&signature), 2215 CBS_len(&signature), eckey); 2216 if (verify <= 0) { 2217 al = SSL_AD_DECRYPT_ERROR; 2218 SSLerror(s, SSL_R_BAD_ECDSA_SIGNATURE); 2219 goto fatal_err; 2220 } 2221 #ifndef OPENSSL_NO_GOST 2222 } else if (EVP_PKEY_id(pkey) == NID_id_GostR3410_94 || 2223 EVP_PKEY_id(pkey) == NID_id_GostR3410_2001) { 2224 unsigned char sigbuf[128]; 2225 unsigned int siglen = sizeof(sigbuf); 2226 EVP_PKEY_CTX *pctx; 2227 const EVP_MD *md; 2228 int nid; 2229 2230 if (!tls1_transcript_data(s, &hdata, &hdatalen)) { 2231 SSLerror(s, ERR_R_INTERNAL_ERROR); 2232 al = SSL_AD_INTERNAL_ERROR; 2233 goto fatal_err; 2234 } 2235 if (!EVP_PKEY_get_default_digest_nid(pkey, &nid) || 2236 !(md = EVP_get_digestbynid(nid))) { 2237 SSLerror(s, ERR_R_EVP_LIB); 2238 al = SSL_AD_INTERNAL_ERROR; 2239 goto fatal_err; 2240 } 2241 if ((pctx = EVP_PKEY_CTX_new(pkey, NULL)) == NULL) { 2242 SSLerror(s, ERR_R_EVP_LIB); 2243 al = SSL_AD_INTERNAL_ERROR; 2244 goto fatal_err; 2245 } 2246 if (!EVP_DigestInit_ex(&mctx, md, NULL) || 2247 !EVP_DigestUpdate(&mctx, hdata, hdatalen) || 2248 !EVP_DigestFinal(&mctx, sigbuf, &siglen) || 2249 (EVP_PKEY_verify_init(pctx) <= 0) || 2250 (EVP_PKEY_CTX_set_signature_md(pctx, md) <= 0) || 2251 (EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_VERIFY, 2252 EVP_PKEY_CTRL_GOST_SIG_FORMAT, 2253 GOST_SIG_FORMAT_RS_LE, NULL) <= 0)) { 2254 SSLerror(s, ERR_R_EVP_LIB); 2255 al = SSL_AD_INTERNAL_ERROR; 2256 EVP_PKEY_CTX_free(pctx); 2257 goto fatal_err; 2258 } 2259 if (EVP_PKEY_verify(pctx, CBS_data(&signature), 2260 CBS_len(&signature), sigbuf, siglen) <= 0) { 2261 al = SSL_AD_DECRYPT_ERROR; 2262 SSLerror(s, SSL_R_BAD_SIGNATURE); 2263 EVP_PKEY_CTX_free(pctx); 2264 goto fatal_err; 2265 } 2266 2267 EVP_PKEY_CTX_free(pctx); 2268 #endif 2269 } else { 2270 SSLerror(s, ERR_R_INTERNAL_ERROR); 2271 al = SSL_AD_UNSUPPORTED_CERTIFICATE; 2272 goto fatal_err; 2273 } 2274 2275 ret = 1; 2276 if (0) { 2277 decode_err: 2278 al = SSL_AD_DECODE_ERROR; 2279 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 2280 fatal_err: 2281 ssl3_send_alert(s, SSL3_AL_FATAL, al); 2282 } 2283 end: 2284 tls1_transcript_free(s); 2285 err: 2286 EVP_MD_CTX_cleanup(&mctx); 2287 EVP_PKEY_free(pkey); 2288 return (ret); 2289 } 2290 2291 int 2292 ssl3_get_client_certificate(SSL *s) 2293 { 2294 CBS cbs, client_certs; 2295 X509 *x = NULL; 2296 const unsigned char *q; 2297 STACK_OF(X509) *sk = NULL; 2298 int i, al, ret; 2299 2300 if ((ret = ssl3_get_message(s, SSL3_ST_SR_CERT_A, SSL3_ST_SR_CERT_B, 2301 -1, s->internal->max_cert_list)) <= 0) 2302 return ret; 2303 2304 ret = -1; 2305 2306 if (S3I(s)->hs.tls12.message_type == SSL3_MT_CLIENT_KEY_EXCHANGE) { 2307 if ((s->verify_mode & SSL_VERIFY_PEER) && 2308 (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { 2309 SSLerror(s, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); 2310 al = SSL_AD_HANDSHAKE_FAILURE; 2311 goto fatal_err; 2312 } 2313 /* 2314 * If tls asked for a client cert, 2315 * the client must return a 0 list. 2316 */ 2317 if (S3I(s)->hs.tls12.cert_request) { 2318 SSLerror(s, SSL_R_TLS_PEER_DID_NOT_RESPOND_WITH_CERTIFICATE_LIST 2319 ); 2320 al = SSL_AD_UNEXPECTED_MESSAGE; 2321 goto fatal_err; 2322 } 2323 S3I(s)->hs.tls12.reuse_message = 1; 2324 return (1); 2325 } 2326 2327 if (S3I(s)->hs.tls12.message_type != SSL3_MT_CERTIFICATE) { 2328 al = SSL_AD_UNEXPECTED_MESSAGE; 2329 SSLerror(s, SSL_R_WRONG_MESSAGE_TYPE); 2330 goto fatal_err; 2331 } 2332 2333 if (s->internal->init_num < 0) 2334 goto decode_err; 2335 2336 CBS_init(&cbs, s->internal->init_msg, s->internal->init_num); 2337 2338 if ((sk = sk_X509_new_null()) == NULL) { 2339 SSLerror(s, ERR_R_MALLOC_FAILURE); 2340 goto err; 2341 } 2342 2343 if (!CBS_get_u24_length_prefixed(&cbs, &client_certs) || 2344 CBS_len(&cbs) != 0) 2345 goto decode_err; 2346 2347 while (CBS_len(&client_certs) > 0) { 2348 CBS cert; 2349 2350 if (!CBS_get_u24_length_prefixed(&client_certs, &cert)) { 2351 al = SSL_AD_DECODE_ERROR; 2352 SSLerror(s, SSL_R_CERT_LENGTH_MISMATCH); 2353 goto fatal_err; 2354 } 2355 2356 q = CBS_data(&cert); 2357 x = d2i_X509(NULL, &q, CBS_len(&cert)); 2358 if (x == NULL) { 2359 SSLerror(s, ERR_R_ASN1_LIB); 2360 goto err; 2361 } 2362 if (q != CBS_data(&cert) + CBS_len(&cert)) { 2363 al = SSL_AD_DECODE_ERROR; 2364 SSLerror(s, SSL_R_CERT_LENGTH_MISMATCH); 2365 goto fatal_err; 2366 } 2367 if (!sk_X509_push(sk, x)) { 2368 SSLerror(s, ERR_R_MALLOC_FAILURE); 2369 goto err; 2370 } 2371 x = NULL; 2372 } 2373 2374 if (sk_X509_num(sk) <= 0) { 2375 /* 2376 * TLS does not mind 0 certs returned. 2377 * Fail for TLS only if we required a certificate. 2378 */ 2379 if ((s->verify_mode & SSL_VERIFY_PEER) && 2380 (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { 2381 SSLerror(s, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); 2382 al = SSL_AD_HANDSHAKE_FAILURE; 2383 goto fatal_err; 2384 } 2385 /* No client certificate so free transcript. */ 2386 tls1_transcript_free(s); 2387 } else { 2388 i = ssl_verify_cert_chain(s, sk); 2389 if (i <= 0) { 2390 al = ssl_verify_alarm_type(s->verify_result); 2391 SSLerror(s, SSL_R_NO_CERTIFICATE_RETURNED); 2392 goto fatal_err; 2393 } 2394 } 2395 2396 X509_free(s->session->peer); 2397 s->session->peer = sk_X509_shift(sk); 2398 s->session->verify_result = s->verify_result; 2399 2400 /* 2401 * With the current implementation, sess_cert will always be NULL 2402 * when we arrive here 2403 */ 2404 if (s->session->sess_cert == NULL) { 2405 s->session->sess_cert = ssl_sess_cert_new(); 2406 if (s->session->sess_cert == NULL) { 2407 SSLerror(s, ERR_R_MALLOC_FAILURE); 2408 goto err; 2409 } 2410 } 2411 sk_X509_pop_free(s->session->sess_cert->cert_chain, X509_free); 2412 s->session->sess_cert->cert_chain = sk; 2413 2414 /* 2415 * Inconsistency alert: cert_chain does *not* include the 2416 * peer's own certificate, while we do include it in s3_clnt.c 2417 */ 2418 2419 sk = NULL; 2420 2421 ret = 1; 2422 if (0) { 2423 decode_err: 2424 al = SSL_AD_DECODE_ERROR; 2425 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 2426 fatal_err: 2427 ssl3_send_alert(s, SSL3_AL_FATAL, al); 2428 } 2429 err: 2430 X509_free(x); 2431 sk_X509_pop_free(sk, X509_free); 2432 2433 return (ret); 2434 } 2435 2436 int 2437 ssl3_send_server_certificate(SSL *s) 2438 { 2439 CBB cbb, server_cert; 2440 CERT_PKEY *cpk; 2441 2442 /* 2443 * Server Certificate - RFC 5246, section 7.4.2. 2444 */ 2445 2446 memset(&cbb, 0, sizeof(cbb)); 2447 2448 if (S3I(s)->hs.state == SSL3_ST_SW_CERT_A) { 2449 if ((cpk = ssl_get_server_send_pkey(s)) == NULL) { 2450 SSLerror(s, ERR_R_INTERNAL_ERROR); 2451 return (0); 2452 } 2453 2454 if (!ssl3_handshake_msg_start(s, &cbb, &server_cert, 2455 SSL3_MT_CERTIFICATE)) 2456 goto err; 2457 if (!ssl3_output_cert_chain(s, &server_cert, cpk)) 2458 goto err; 2459 if (!ssl3_handshake_msg_finish(s, &cbb)) 2460 goto err; 2461 2462 S3I(s)->hs.state = SSL3_ST_SW_CERT_B; 2463 } 2464 2465 /* SSL3_ST_SW_CERT_B */ 2466 return (ssl3_handshake_write(s)); 2467 2468 err: 2469 CBB_cleanup(&cbb); 2470 2471 return (0); 2472 } 2473 2474 /* send a new session ticket (not necessarily for a new session) */ 2475 int 2476 ssl3_send_newsession_ticket(SSL *s) 2477 { 2478 CBB cbb, session_ticket, ticket; 2479 SSL_CTX *tctx = s->initial_ctx; 2480 size_t enc_session_len, enc_session_max_len, hmac_len; 2481 size_t session_len = 0; 2482 unsigned char *enc_session = NULL, *session = NULL; 2483 unsigned char iv[EVP_MAX_IV_LENGTH]; 2484 unsigned char key_name[16]; 2485 unsigned char *hmac; 2486 unsigned int hlen; 2487 EVP_CIPHER_CTX ctx; 2488 HMAC_CTX hctx; 2489 int len; 2490 2491 /* 2492 * New Session Ticket - RFC 5077, section 3.3. 2493 */ 2494 2495 EVP_CIPHER_CTX_init(&ctx); 2496 HMAC_CTX_init(&hctx); 2497 2498 memset(&cbb, 0, sizeof(cbb)); 2499 2500 if (S3I(s)->hs.state == SSL3_ST_SW_SESSION_TICKET_A) { 2501 if (!ssl3_handshake_msg_start(s, &cbb, &session_ticket, 2502 SSL3_MT_NEWSESSION_TICKET)) 2503 goto err; 2504 2505 if (!SSL_SESSION_ticket(s->session, &session, &session_len)) 2506 goto err; 2507 if (session_len > 0xffff) 2508 goto err; 2509 2510 /* 2511 * Initialize HMAC and cipher contexts. If callback is present 2512 * it does all the work, otherwise use generated values from 2513 * parent context. 2514 */ 2515 if (tctx->internal->tlsext_ticket_key_cb != NULL) { 2516 if (tctx->internal->tlsext_ticket_key_cb(s, 2517 key_name, iv, &ctx, &hctx, 1) < 0) { 2518 EVP_CIPHER_CTX_cleanup(&ctx); 2519 goto err; 2520 } 2521 } else { 2522 arc4random_buf(iv, 16); 2523 EVP_EncryptInit_ex(&ctx, EVP_aes_128_cbc(), NULL, 2524 tctx->internal->tlsext_tick_aes_key, iv); 2525 HMAC_Init_ex(&hctx, tctx->internal->tlsext_tick_hmac_key, 2526 16, EVP_sha256(), NULL); 2527 memcpy(key_name, tctx->internal->tlsext_tick_key_name, 16); 2528 } 2529 2530 /* Encrypt the session state. */ 2531 enc_session_max_len = session_len + EVP_MAX_BLOCK_LENGTH; 2532 if ((enc_session = calloc(1, enc_session_max_len)) == NULL) 2533 goto err; 2534 enc_session_len = 0; 2535 if (!EVP_EncryptUpdate(&ctx, enc_session, &len, session, 2536 session_len)) 2537 goto err; 2538 enc_session_len += len; 2539 if (!EVP_EncryptFinal_ex(&ctx, enc_session + enc_session_len, 2540 &len)) 2541 goto err; 2542 enc_session_len += len; 2543 2544 if (enc_session_len > enc_session_max_len) 2545 goto err; 2546 2547 /* Generate the HMAC. */ 2548 if (!HMAC_Update(&hctx, key_name, sizeof(key_name))) 2549 goto err; 2550 if (!HMAC_Update(&hctx, iv, EVP_CIPHER_CTX_iv_length(&ctx))) 2551 goto err; 2552 if (!HMAC_Update(&hctx, enc_session, enc_session_len)) 2553 goto err; 2554 2555 if ((hmac_len = HMAC_size(&hctx)) <= 0) 2556 goto err; 2557 2558 /* 2559 * Ticket lifetime hint (advisory only): 2560 * We leave this unspecified for resumed session 2561 * (for simplicity), and guess that tickets for new 2562 * sessions will live as long as their sessions. 2563 */ 2564 if (!CBB_add_u32(&session_ticket, 2565 s->internal->hit ? 0 : s->session->timeout)) 2566 goto err; 2567 2568 if (!CBB_add_u16_length_prefixed(&session_ticket, &ticket)) 2569 goto err; 2570 if (!CBB_add_bytes(&ticket, key_name, sizeof(key_name))) 2571 goto err; 2572 if (!CBB_add_bytes(&ticket, iv, EVP_CIPHER_CTX_iv_length(&ctx))) 2573 goto err; 2574 if (!CBB_add_bytes(&ticket, enc_session, enc_session_len)) 2575 goto err; 2576 if (!CBB_add_space(&ticket, &hmac, hmac_len)) 2577 goto err; 2578 2579 if (!HMAC_Final(&hctx, hmac, &hlen)) 2580 goto err; 2581 if (hlen != hmac_len) 2582 goto err; 2583 2584 if (!ssl3_handshake_msg_finish(s, &cbb)) 2585 goto err; 2586 2587 S3I(s)->hs.state = SSL3_ST_SW_SESSION_TICKET_B; 2588 } 2589 2590 EVP_CIPHER_CTX_cleanup(&ctx); 2591 HMAC_CTX_cleanup(&hctx); 2592 freezero(session, session_len); 2593 free(enc_session); 2594 2595 /* SSL3_ST_SW_SESSION_TICKET_B */ 2596 return (ssl3_handshake_write(s)); 2597 2598 err: 2599 CBB_cleanup(&cbb); 2600 EVP_CIPHER_CTX_cleanup(&ctx); 2601 HMAC_CTX_cleanup(&hctx); 2602 freezero(session, session_len); 2603 free(enc_session); 2604 2605 return (-1); 2606 } 2607 2608 int 2609 ssl3_send_cert_status(SSL *s) 2610 { 2611 CBB cbb, certstatus, ocspresp; 2612 2613 memset(&cbb, 0, sizeof(cbb)); 2614 2615 if (S3I(s)->hs.state == SSL3_ST_SW_CERT_STATUS_A) { 2616 if (!ssl3_handshake_msg_start(s, &cbb, &certstatus, 2617 SSL3_MT_CERTIFICATE_STATUS)) 2618 goto err; 2619 if (!CBB_add_u8(&certstatus, s->tlsext_status_type)) 2620 goto err; 2621 if (!CBB_add_u24_length_prefixed(&certstatus, &ocspresp)) 2622 goto err; 2623 if (!CBB_add_bytes(&ocspresp, s->internal->tlsext_ocsp_resp, 2624 s->internal->tlsext_ocsp_resp_len)) 2625 goto err; 2626 if (!ssl3_handshake_msg_finish(s, &cbb)) 2627 goto err; 2628 2629 S3I(s)->hs.state = SSL3_ST_SW_CERT_STATUS_B; 2630 } 2631 2632 /* SSL3_ST_SW_CERT_STATUS_B */ 2633 return (ssl3_handshake_write(s)); 2634 2635 err: 2636 CBB_cleanup(&cbb); 2637 2638 return (-1); 2639 } 2640