1 /* $OpenBSD: ssl_srvr.c,v 1.48 2018/08/27 17:04:34 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 "ssl_locl.h" 154 155 #include <openssl/bn.h> 156 #include <openssl/buffer.h> 157 #include <openssl/curve25519.h> 158 #include <openssl/evp.h> 159 #include <openssl/dh.h> 160 #ifndef OPENSSL_NO_GOST 161 #include <openssl/gost.h> 162 #endif 163 #include <openssl/hmac.h> 164 #include <openssl/md5.h> 165 #include <openssl/objects.h> 166 #include <openssl/x509.h> 167 168 #include "bytestring.h" 169 #include "ssl_tlsext.h" 170 171 int 172 ssl3_accept(SSL *s) 173 { 174 void (*cb)(const SSL *ssl, int type, int val) = NULL; 175 unsigned long alg_k; 176 int ret = -1; 177 int new_state, state, skip = 0; 178 int listen = 0; 179 180 ERR_clear_error(); 181 errno = 0; 182 183 if (s->internal->info_callback != NULL) 184 cb = s->internal->info_callback; 185 else if (s->ctx->internal->info_callback != NULL) 186 cb = s->ctx->internal->info_callback; 187 188 if (SSL_IS_DTLS(s)) 189 listen = D1I(s)->listen; 190 191 /* init things to blank */ 192 s->internal->in_handshake++; 193 if (!SSL_in_init(s) || SSL_in_before(s)) 194 SSL_clear(s); 195 196 if (SSL_IS_DTLS(s)) 197 D1I(s)->listen = listen; 198 199 if (s->cert == NULL) { 200 SSLerror(s, SSL_R_NO_CERTIFICATE_SET); 201 ret = -1; 202 goto end; 203 } 204 205 for (;;) { 206 state = S3I(s)->hs.state; 207 208 switch (S3I(s)->hs.state) { 209 case SSL_ST_RENEGOTIATE: 210 s->internal->renegotiate = 1; 211 /* S3I(s)->hs.state=SSL_ST_ACCEPT; */ 212 213 case SSL_ST_BEFORE: 214 case SSL_ST_ACCEPT: 215 case SSL_ST_BEFORE|SSL_ST_ACCEPT: 216 case SSL_ST_OK|SSL_ST_ACCEPT: 217 s->server = 1; 218 if (cb != NULL) 219 cb(s, SSL_CB_HANDSHAKE_START, 1); 220 221 if (SSL_IS_DTLS(s)) { 222 if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00)) { 223 SSLerror(s, ERR_R_INTERNAL_ERROR); 224 ret = -1; 225 goto end; 226 } 227 } else { 228 if ((s->version >> 8) != 3) { 229 SSLerror(s, ERR_R_INTERNAL_ERROR); 230 ret = -1; 231 goto end; 232 } 233 } 234 s->internal->type = SSL_ST_ACCEPT; 235 236 if (!ssl3_setup_init_buffer(s)) { 237 ret = -1; 238 goto end; 239 } 240 if (!ssl3_setup_buffers(s)) { 241 ret = -1; 242 goto end; 243 } 244 245 s->internal->init_num = 0; 246 247 if (S3I(s)->hs.state != SSL_ST_RENEGOTIATE) { 248 /* 249 * Ok, we now need to push on a buffering BIO 250 * so that the output is sent in a way that 251 * TCP likes :-) 252 */ 253 if (!ssl_init_wbio_buffer(s, 1)) { 254 ret = -1; 255 goto end; 256 } 257 if (!tls1_init_finished_mac(s)) { 258 ret = -1; 259 goto end; 260 } 261 262 S3I(s)->hs.state = SSL3_ST_SR_CLNT_HELLO_A; 263 s->ctx->internal->stats.sess_accept++; 264 } else if (!SSL_IS_DTLS(s) && !S3I(s)->send_connection_binding) { 265 /* 266 * Server attempting to renegotiate with 267 * client that doesn't support secure 268 * renegotiation. 269 */ 270 SSLerror(s, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED); 271 ssl3_send_alert(s, SSL3_AL_FATAL, 272 SSL_AD_HANDSHAKE_FAILURE); 273 ret = -1; 274 goto end; 275 } else { 276 /* 277 * S3I(s)->hs.state == SSL_ST_RENEGOTIATE, 278 * we will just send a HelloRequest. 279 */ 280 s->ctx->internal->stats.sess_accept_renegotiate++; 281 S3I(s)->hs.state = SSL3_ST_SW_HELLO_REQ_A; 282 } 283 break; 284 285 case SSL3_ST_SW_HELLO_REQ_A: 286 case SSL3_ST_SW_HELLO_REQ_B: 287 s->internal->shutdown = 0; 288 if (SSL_IS_DTLS(s)) { 289 dtls1_clear_record_buffer(s); 290 dtls1_start_timer(s); 291 } 292 ret = ssl3_send_hello_request(s); 293 if (ret <= 0) 294 goto end; 295 if (SSL_IS_DTLS(s)) 296 S3I(s)->hs.next_state = SSL3_ST_SR_CLNT_HELLO_A; 297 else 298 S3I(s)->hs.next_state = SSL3_ST_SW_HELLO_REQ_C; 299 S3I(s)->hs.state = SSL3_ST_SW_FLUSH; 300 s->internal->init_num = 0; 301 302 if (!tls1_init_finished_mac(s)) { 303 ret = -1; 304 goto end; 305 } 306 break; 307 308 case SSL3_ST_SW_HELLO_REQ_C: 309 S3I(s)->hs.state = SSL_ST_OK; 310 break; 311 312 case SSL3_ST_SR_CLNT_HELLO_A: 313 case SSL3_ST_SR_CLNT_HELLO_B: 314 case SSL3_ST_SR_CLNT_HELLO_C: 315 s->internal->shutdown = 0; 316 if (SSL_IS_DTLS(s)) { 317 ret = ssl3_get_client_hello(s); 318 if (ret <= 0) 319 goto end; 320 dtls1_stop_timer(s); 321 322 if (ret == 1 && 323 (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE)) 324 S3I(s)->hs.state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A; 325 else 326 S3I(s)->hs.state = SSL3_ST_SW_SRVR_HELLO_A; 327 328 s->internal->init_num = 0; 329 330 /* 331 * Reflect ClientHello sequence to remain 332 * stateless while listening. 333 */ 334 if (listen) { 335 memcpy(S3I(s)->write_sequence, 336 S3I(s)->read_sequence, 337 sizeof(S3I(s)->write_sequence)); 338 } 339 340 /* If we're just listening, stop here */ 341 if (listen && S3I(s)->hs.state == SSL3_ST_SW_SRVR_HELLO_A) { 342 ret = 2; 343 D1I(s)->listen = 0; 344 /* 345 * Set expected sequence numbers to 346 * continue the handshake. 347 */ 348 D1I(s)->handshake_read_seq = 2; 349 D1I(s)->handshake_write_seq = 1; 350 D1I(s)->next_handshake_write_seq = 1; 351 goto end; 352 } 353 } else { 354 if (s->internal->rwstate != SSL_X509_LOOKUP) { 355 ret = ssl3_get_client_hello(s); 356 if (ret <= 0) 357 goto end; 358 } 359 360 s->internal->renegotiate = 2; 361 S3I(s)->hs.state = SSL3_ST_SW_SRVR_HELLO_A; 362 s->internal->init_num = 0; 363 } 364 break; 365 366 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A: 367 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B: 368 ret = dtls1_send_hello_verify_request(s); 369 if (ret <= 0) 370 goto end; 371 S3I(s)->hs.state = SSL3_ST_SW_FLUSH; 372 S3I(s)->hs.next_state = SSL3_ST_SR_CLNT_HELLO_A; 373 374 /* HelloVerifyRequest resets Finished MAC. */ 375 if (!tls1_init_finished_mac(s)) { 376 ret = -1; 377 goto end; 378 } 379 break; 380 381 case SSL3_ST_SW_SRVR_HELLO_A: 382 case SSL3_ST_SW_SRVR_HELLO_B: 383 if (SSL_IS_DTLS(s)) { 384 s->internal->renegotiate = 2; 385 dtls1_start_timer(s); 386 } 387 ret = ssl3_send_server_hello(s); 388 if (ret <= 0) 389 goto end; 390 if (s->internal->hit) { 391 if (s->internal->tlsext_ticket_expected) 392 S3I(s)->hs.state = SSL3_ST_SW_SESSION_TICKET_A; 393 else 394 S3I(s)->hs.state = SSL3_ST_SW_CHANGE_A; 395 } else { 396 S3I(s)->hs.state = SSL3_ST_SW_CERT_A; 397 } 398 s->internal->init_num = 0; 399 break; 400 401 case SSL3_ST_SW_CERT_A: 402 case SSL3_ST_SW_CERT_B: 403 /* Check if it is anon DH or anon ECDH. */ 404 if (!(S3I(s)->hs.new_cipher->algorithm_auth & 405 SSL_aNULL)) { 406 if (SSL_IS_DTLS(s)) 407 dtls1_start_timer(s); 408 ret = ssl3_send_server_certificate(s); 409 if (ret <= 0) 410 goto end; 411 if (s->internal->tlsext_status_expected) 412 S3I(s)->hs.state = SSL3_ST_SW_CERT_STATUS_A; 413 else 414 S3I(s)->hs.state = SSL3_ST_SW_KEY_EXCH_A; 415 } else { 416 skip = 1; 417 S3I(s)->hs.state = SSL3_ST_SW_KEY_EXCH_A; 418 } 419 s->internal->init_num = 0; 420 break; 421 422 case SSL3_ST_SW_KEY_EXCH_A: 423 case SSL3_ST_SW_KEY_EXCH_B: 424 alg_k = S3I(s)->hs.new_cipher->algorithm_mkey; 425 426 /* 427 * Only send if using a DH key exchange. 428 * 429 * For ECC ciphersuites, we send a ServerKeyExchange 430 * message only if the cipher suite is ECDHE. In other 431 * cases, the server certificate contains the server's 432 * public key for key exchange. 433 */ 434 if (alg_k & (SSL_kDHE|SSL_kECDHE)) { 435 if (SSL_IS_DTLS(s)) 436 dtls1_start_timer(s); 437 ret = ssl3_send_server_key_exchange(s); 438 if (ret <= 0) 439 goto end; 440 } else 441 skip = 1; 442 443 S3I(s)->hs.state = SSL3_ST_SW_CERT_REQ_A; 444 s->internal->init_num = 0; 445 break; 446 447 case SSL3_ST_SW_CERT_REQ_A: 448 case SSL3_ST_SW_CERT_REQ_B: 449 /* 450 * Determine whether or not we need to request a 451 * certificate. 452 * 453 * Do not request a certificate if: 454 * 455 * - We did not ask for it (SSL_VERIFY_PEER is unset). 456 * 457 * - SSL_VERIFY_CLIENT_ONCE is set and we are 458 * renegotiating. 459 * 460 * - We are using an anonymous ciphersuites 461 * (see section "Certificate request" in SSL 3 drafts 462 * and in RFC 2246) ... except when the application 463 * insists on verification (against the specs, but 464 * s3_clnt.c accepts this for SSL 3). 465 */ 466 if (!(s->verify_mode & SSL_VERIFY_PEER) || 467 ((s->session->peer != NULL) && 468 (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) || 469 ((S3I(s)->hs.new_cipher->algorithm_auth & 470 SSL_aNULL) && !(s->verify_mode & 471 SSL_VERIFY_FAIL_IF_NO_PEER_CERT))) { 472 /* No cert request. */ 473 skip = 1; 474 S3I(s)->tmp.cert_request = 0; 475 S3I(s)->hs.state = SSL3_ST_SW_SRVR_DONE_A; 476 if (!SSL_IS_DTLS(s) && S3I(s)->handshake_buffer) { 477 if (!tls1_digest_cached_records(s)) { 478 ret = -1; 479 goto end; 480 } 481 } 482 } else { 483 S3I(s)->tmp.cert_request = 1; 484 if (SSL_IS_DTLS(s)) 485 dtls1_start_timer(s); 486 ret = ssl3_send_certificate_request(s); 487 if (ret <= 0) 488 goto end; 489 S3I(s)->hs.state = SSL3_ST_SW_SRVR_DONE_A; 490 s->internal->init_num = 0; 491 } 492 break; 493 494 case SSL3_ST_SW_SRVR_DONE_A: 495 case SSL3_ST_SW_SRVR_DONE_B: 496 if (SSL_IS_DTLS(s)) 497 dtls1_start_timer(s); 498 ret = ssl3_send_server_done(s); 499 if (ret <= 0) 500 goto end; 501 S3I(s)->hs.next_state = SSL3_ST_SR_CERT_A; 502 S3I(s)->hs.state = SSL3_ST_SW_FLUSH; 503 s->internal->init_num = 0; 504 break; 505 506 case SSL3_ST_SW_FLUSH: 507 /* 508 * This code originally checked to see if 509 * any data was pending using BIO_CTRL_INFO 510 * and then flushed. This caused problems 511 * as documented in PR#1939. The proposed 512 * fix doesn't completely resolve this issue 513 * as buggy implementations of BIO_CTRL_PENDING 514 * still exist. So instead we just flush 515 * unconditionally. 516 */ 517 s->internal->rwstate = SSL_WRITING; 518 if (BIO_flush(s->wbio) <= 0) { 519 if (SSL_IS_DTLS(s)) { 520 /* If the write error was fatal, stop trying. */ 521 if (!BIO_should_retry(s->wbio)) { 522 s->internal->rwstate = SSL_NOTHING; 523 S3I(s)->hs.state = S3I(s)->hs.next_state; 524 } 525 } 526 ret = -1; 527 goto end; 528 } 529 s->internal->rwstate = SSL_NOTHING; 530 S3I(s)->hs.state = S3I(s)->hs.next_state; 531 break; 532 533 case SSL3_ST_SR_CERT_A: 534 case SSL3_ST_SR_CERT_B: 535 if (S3I(s)->tmp.cert_request) { 536 ret = ssl3_get_client_certificate(s); 537 if (ret <= 0) 538 goto end; 539 } 540 s->internal->init_num = 0; 541 S3I(s)->hs.state = SSL3_ST_SR_KEY_EXCH_A; 542 break; 543 544 case SSL3_ST_SR_KEY_EXCH_A: 545 case SSL3_ST_SR_KEY_EXCH_B: 546 ret = ssl3_get_client_key_exchange(s); 547 if (ret <= 0) 548 goto end; 549 550 if (SSL_IS_DTLS(s)) { 551 S3I(s)->hs.state = SSL3_ST_SR_CERT_VRFY_A; 552 s->internal->init_num = 0; 553 } 554 555 alg_k = S3I(s)->hs.new_cipher->algorithm_mkey; 556 if (ret == 2) { 557 /* 558 * For the ECDH ciphersuites when 559 * the client sends its ECDH pub key in 560 * a certificate, the CertificateVerify 561 * message is not sent. 562 * Also for GOST ciphersuites when 563 * the client uses its key from the certificate 564 * for key exchange. 565 */ 566 S3I(s)->hs.state = SSL3_ST_SR_FINISHED_A; 567 s->internal->init_num = 0; 568 } else if (SSL_USE_SIGALGS(s) || (alg_k & SSL_kGOST)) { 569 S3I(s)->hs.state = SSL3_ST_SR_CERT_VRFY_A; 570 s->internal->init_num = 0; 571 if (!s->session->peer) 572 break; 573 /* 574 * For sigalgs freeze the handshake buffer 575 * at this point and digest cached records. 576 */ 577 if (!S3I(s)->handshake_buffer) { 578 SSLerror(s, ERR_R_INTERNAL_ERROR); 579 ret = -1; 580 goto end; 581 } 582 s->s3->flags |= TLS1_FLAGS_KEEP_HANDSHAKE; 583 if (!tls1_digest_cached_records(s)) { 584 ret = -1; 585 goto end; 586 } 587 } else { 588 S3I(s)->hs.state = SSL3_ST_SR_CERT_VRFY_A; 589 s->internal->init_num = 0; 590 591 /* 592 * We need to get hashes here so if there is 593 * a client cert, it can be verified. 594 */ 595 if (S3I(s)->handshake_buffer) { 596 if (!tls1_digest_cached_records(s)) { 597 ret = -1; 598 goto end; 599 } 600 } 601 if (!tls1_handshake_hash_value(s, 602 S3I(s)->tmp.cert_verify_md, 603 sizeof(S3I(s)->tmp.cert_verify_md), 604 NULL)) { 605 ret = -1; 606 goto end; 607 } 608 } 609 break; 610 611 case SSL3_ST_SR_CERT_VRFY_A: 612 case SSL3_ST_SR_CERT_VRFY_B: 613 if (SSL_IS_DTLS(s)) 614 D1I(s)->change_cipher_spec_ok = 1; 615 else 616 s->s3->flags |= SSL3_FLAGS_CCS_OK; 617 618 /* we should decide if we expected this one */ 619 ret = ssl3_get_cert_verify(s); 620 if (ret <= 0) 621 goto end; 622 S3I(s)->hs.state = SSL3_ST_SR_FINISHED_A; 623 s->internal->init_num = 0; 624 break; 625 626 case SSL3_ST_SR_FINISHED_A: 627 case SSL3_ST_SR_FINISHED_B: 628 if (SSL_IS_DTLS(s)) 629 D1I(s)->change_cipher_spec_ok = 1; 630 else 631 s->s3->flags |= SSL3_FLAGS_CCS_OK; 632 ret = ssl3_get_finished(s, SSL3_ST_SR_FINISHED_A, 633 SSL3_ST_SR_FINISHED_B); 634 if (ret <= 0) 635 goto end; 636 if (SSL_IS_DTLS(s)) 637 dtls1_stop_timer(s); 638 if (s->internal->hit) 639 S3I(s)->hs.state = SSL_ST_OK; 640 else if (s->internal->tlsext_ticket_expected) 641 S3I(s)->hs.state = SSL3_ST_SW_SESSION_TICKET_A; 642 else 643 S3I(s)->hs.state = SSL3_ST_SW_CHANGE_A; 644 s->internal->init_num = 0; 645 break; 646 647 case SSL3_ST_SW_SESSION_TICKET_A: 648 case SSL3_ST_SW_SESSION_TICKET_B: 649 ret = ssl3_send_newsession_ticket(s); 650 if (ret <= 0) 651 goto end; 652 S3I(s)->hs.state = SSL3_ST_SW_CHANGE_A; 653 s->internal->init_num = 0; 654 break; 655 656 case SSL3_ST_SW_CERT_STATUS_A: 657 case SSL3_ST_SW_CERT_STATUS_B: 658 ret = ssl3_send_cert_status(s); 659 if (ret <= 0) 660 goto end; 661 S3I(s)->hs.state = SSL3_ST_SW_KEY_EXCH_A; 662 s->internal->init_num = 0; 663 break; 664 665 case SSL3_ST_SW_CHANGE_A: 666 case SSL3_ST_SW_CHANGE_B: 667 s->session->cipher = S3I(s)->hs.new_cipher; 668 if (!tls1_setup_key_block(s)) { 669 ret = -1; 670 goto end; 671 } 672 673 ret = ssl3_send_change_cipher_spec(s, 674 SSL3_ST_SW_CHANGE_A, SSL3_ST_SW_CHANGE_B); 675 if (ret <= 0) 676 goto end; 677 S3I(s)->hs.state = SSL3_ST_SW_FINISHED_A; 678 s->internal->init_num = 0; 679 680 if (!tls1_change_cipher_state(s, 681 SSL3_CHANGE_CIPHER_SERVER_WRITE)) { 682 ret = -1; 683 goto end; 684 } 685 686 if (SSL_IS_DTLS(s)) 687 dtls1_reset_seq_numbers(s, SSL3_CC_WRITE); 688 break; 689 690 case SSL3_ST_SW_FINISHED_A: 691 case SSL3_ST_SW_FINISHED_B: 692 ret = ssl3_send_finished(s, 693 SSL3_ST_SW_FINISHED_A, SSL3_ST_SW_FINISHED_B, 694 TLS_MD_SERVER_FINISH_CONST, 695 TLS_MD_SERVER_FINISH_CONST_SIZE); 696 if (ret <= 0) 697 goto end; 698 S3I(s)->hs.state = SSL3_ST_SW_FLUSH; 699 if (s->internal->hit) 700 S3I(s)->hs.next_state = SSL3_ST_SR_FINISHED_A; 701 else 702 S3I(s)->hs.next_state = SSL_ST_OK; 703 s->internal->init_num = 0; 704 break; 705 706 case SSL_ST_OK: 707 /* clean a few things up */ 708 tls1_cleanup_key_block(s); 709 710 if (!SSL_IS_DTLS(s)) { 711 BUF_MEM_free(s->internal->init_buf); 712 s->internal->init_buf = NULL; 713 } 714 715 /* remove buffering on output */ 716 ssl_free_wbio_buffer(s); 717 718 s->internal->init_num = 0; 719 720 /* Skipped if we just sent a HelloRequest. */ 721 if (s->internal->renegotiate == 2) { 722 s->internal->renegotiate = 0; 723 s->internal->new_session = 0; 724 725 ssl_update_cache(s, SSL_SESS_CACHE_SERVER); 726 727 s->ctx->internal->stats.sess_accept_good++; 728 /* s->server=1; */ 729 s->internal->handshake_func = ssl3_accept; 730 731 if (cb != NULL) 732 cb(s, SSL_CB_HANDSHAKE_DONE, 1); 733 } 734 735 ret = 1; 736 737 if (SSL_IS_DTLS(s)) { 738 /* Done handshaking, next message is client hello. */ 739 D1I(s)->handshake_read_seq = 0; 740 /* Next message is server hello. */ 741 D1I(s)->handshake_write_seq = 0; 742 D1I(s)->next_handshake_write_seq = 0; 743 } 744 goto end; 745 /* break; */ 746 747 default: 748 SSLerror(s, SSL_R_UNKNOWN_STATE); 749 ret = -1; 750 goto end; 751 /* break; */ 752 } 753 754 if (!S3I(s)->tmp.reuse_message && !skip) { 755 if (s->internal->debug) { 756 if ((ret = BIO_flush(s->wbio)) <= 0) 757 goto end; 758 } 759 760 761 if ((cb != NULL) && (S3I(s)->hs.state != state)) { 762 new_state = S3I(s)->hs.state; 763 S3I(s)->hs.state = state; 764 cb(s, SSL_CB_ACCEPT_LOOP, 1); 765 S3I(s)->hs.state = new_state; 766 } 767 } 768 skip = 0; 769 } 770 end: 771 /* BIO_flush(s->wbio); */ 772 s->internal->in_handshake--; 773 if (cb != NULL) 774 cb(s, SSL_CB_ACCEPT_EXIT, ret); 775 776 return (ret); 777 } 778 779 int 780 ssl3_send_hello_request(SSL *s) 781 { 782 CBB cbb, hello; 783 784 memset(&cbb, 0, sizeof(cbb)); 785 786 if (S3I(s)->hs.state == SSL3_ST_SW_HELLO_REQ_A) { 787 if (!ssl3_handshake_msg_start(s, &cbb, &hello, 788 SSL3_MT_HELLO_REQUEST)) 789 goto err; 790 if (!ssl3_handshake_msg_finish(s, &cbb)) 791 goto err; 792 793 S3I(s)->hs.state = SSL3_ST_SW_HELLO_REQ_B; 794 } 795 796 /* SSL3_ST_SW_HELLO_REQ_B */ 797 return (ssl3_handshake_write(s)); 798 799 err: 800 CBB_cleanup(&cbb); 801 802 return (-1); 803 } 804 805 int 806 ssl3_get_client_hello(SSL *s) 807 { 808 CBS cbs, client_random, session_id, cookie, cipher_suites; 809 CBS compression_methods; 810 uint16_t client_version; 811 uint8_t comp_method; 812 int comp_null; 813 int i, j, ok, al, ret = -1, cookie_valid = 0; 814 long n; 815 unsigned long id; 816 SSL_CIPHER *c; 817 STACK_OF(SSL_CIPHER) *ciphers = NULL; 818 unsigned long alg_k; 819 const SSL_METHOD *method; 820 uint16_t shared_version; 821 822 /* 823 * We do this so that we will respond with our native type. 824 * If we are TLSv1 and we get SSLv3, we will respond with TLSv1, 825 * This down switching should be handled by a different method. 826 * If we are SSLv3, we will respond with SSLv3, even if prompted with 827 * TLSv1. 828 */ 829 if (S3I(s)->hs.state == SSL3_ST_SR_CLNT_HELLO_A) { 830 S3I(s)->hs.state = SSL3_ST_SR_CLNT_HELLO_B; 831 } 832 833 s->internal->first_packet = 1; 834 n = s->method->internal->ssl_get_message(s, SSL3_ST_SR_CLNT_HELLO_B, 835 SSL3_ST_SR_CLNT_HELLO_C, SSL3_MT_CLIENT_HELLO, 836 SSL3_RT_MAX_PLAIN_LENGTH, &ok); 837 if (!ok) 838 return ((int)n); 839 s->internal->first_packet = 0; 840 841 if (n < 0) 842 goto err; 843 844 CBS_init(&cbs, s->internal->init_msg, n); 845 846 /* Parse client hello up until the extensions (if any). */ 847 if (!CBS_get_u16(&cbs, &client_version)) 848 goto truncated; 849 if (!CBS_get_bytes(&cbs, &client_random, SSL3_RANDOM_SIZE)) 850 goto truncated; 851 if (!CBS_get_u8_length_prefixed(&cbs, &session_id)) 852 goto truncated; 853 if (SSL_IS_DTLS(s)) { 854 if (!CBS_get_u8_length_prefixed(&cbs, &cookie)) 855 goto truncated; 856 } 857 if (!CBS_get_u16_length_prefixed(&cbs, &cipher_suites)) 858 goto truncated; 859 if (!CBS_get_u8_length_prefixed(&cbs, &compression_methods)) 860 goto truncated; 861 862 /* 863 * Use version from inside client hello, not from record header. 864 * (may differ: see RFC 2246, Appendix E, second paragraph) 865 */ 866 if (ssl_max_shared_version(s, client_version, &shared_version) != 1) { 867 SSLerror(s, SSL_R_WRONG_VERSION_NUMBER); 868 if ((s->client_version >> 8) == SSL3_VERSION_MAJOR && 869 !s->internal->enc_write_ctx && !s->internal->write_hash) { 870 /* 871 * Similar to ssl3_get_record, send alert using remote 872 * version number. 873 */ 874 s->version = s->client_version; 875 } 876 al = SSL_AD_PROTOCOL_VERSION; 877 goto f_err; 878 } 879 s->client_version = client_version; 880 s->version = shared_version; 881 882 if ((method = tls1_get_server_method(shared_version)) == NULL) 883 method = dtls1_get_server_method(shared_version); 884 if (method == NULL) { 885 SSLerror(s, ERR_R_INTERNAL_ERROR); 886 goto err; 887 } 888 s->method = method; 889 890 /* 891 * If we require cookies (DTLS) and this ClientHello does not contain 892 * one, just return since we do not want to allocate any memory yet. 893 * So check cookie length... 894 */ 895 if (SSL_IS_DTLS(s)) { 896 if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) { 897 if (CBS_len(&cookie) == 0) 898 return (1); 899 } 900 } 901 902 if (!CBS_write_bytes(&client_random, s->s3->client_random, 903 sizeof(s->s3->client_random), NULL)) 904 goto err; 905 906 s->internal->hit = 0; 907 908 /* 909 * Versions before 0.9.7 always allow clients to resume sessions in 910 * renegotiation. 0.9.7 and later allow this by default, but optionally 911 * ignore resumption requests with flag 912 * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION (it's a new flag 913 * rather than a change to default behavior so that applications 914 * relying on this for security won't even compile against older 915 * library versions). 916 * 917 * 1.0.1 and later also have a function SSL_renegotiate_abbreviated() 918 * to request renegotiation but not a new session (s->internal->new_session 919 * remains unset): for servers, this essentially just means that the 920 * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION setting will be 921 * ignored. 922 */ 923 if ((s->internal->new_session && (s->internal->options & 924 SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION))) { 925 if (!ssl_get_new_session(s, 1)) 926 goto err; 927 } else { 928 CBS ext_block; 929 930 CBS_dup(&cbs, &ext_block); 931 932 i = ssl_get_prev_session(s, CBS_data(&session_id), 933 CBS_len(&session_id), &ext_block); 934 if (i == 1) { /* previous session */ 935 s->internal->hit = 1; 936 } else if (i == -1) 937 goto err; 938 else { 939 /* i == 0 */ 940 if (!ssl_get_new_session(s, 1)) 941 goto err; 942 } 943 } 944 945 if (SSL_IS_DTLS(s)) { 946 /* 947 * The ClientHello may contain a cookie even if the HelloVerify 948 * message has not been sent - make sure that it does not cause 949 * an overflow. 950 */ 951 if (CBS_len(&cookie) > sizeof(D1I(s)->rcvd_cookie)) { 952 al = SSL_AD_DECODE_ERROR; 953 SSLerror(s, SSL_R_COOKIE_MISMATCH); 954 goto f_err; 955 } 956 957 /* Verify the cookie if appropriate option is set. */ 958 if ((SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) && 959 CBS_len(&cookie) > 0) { 960 size_t cookie_len; 961 962 /* XXX - rcvd_cookie seems to only be used here... */ 963 if (!CBS_write_bytes(&cookie, D1I(s)->rcvd_cookie, 964 sizeof(D1I(s)->rcvd_cookie), &cookie_len)) 965 goto err; 966 967 if (s->ctx->internal->app_verify_cookie_cb != NULL) { 968 if (s->ctx->internal->app_verify_cookie_cb(s, 969 D1I(s)->rcvd_cookie, cookie_len) == 0) { 970 al = SSL_AD_HANDSHAKE_FAILURE; 971 SSLerror(s, SSL_R_COOKIE_MISMATCH); 972 goto f_err; 973 } 974 /* else cookie verification succeeded */ 975 /* XXX - can d1->cookie_len > sizeof(rcvd_cookie) ? */ 976 } else if (timingsafe_memcmp(D1I(s)->rcvd_cookie, 977 D1I(s)->cookie, D1I(s)->cookie_len) != 0) { 978 /* default verification */ 979 al = SSL_AD_HANDSHAKE_FAILURE; 980 SSLerror(s, SSL_R_COOKIE_MISMATCH); 981 goto f_err; 982 } 983 cookie_valid = 1; 984 } 985 } 986 987 /* XXX - This logic seems wrong... */ 988 if (CBS_len(&cipher_suites) == 0 && CBS_len(&session_id) != 0) { 989 /* we need a cipher if we are not resuming a session */ 990 al = SSL_AD_ILLEGAL_PARAMETER; 991 SSLerror(s, SSL_R_NO_CIPHERS_SPECIFIED); 992 goto f_err; 993 } 994 995 if (CBS_len(&cipher_suites) > 0) { 996 if ((ciphers = ssl_bytes_to_cipher_list(s, 997 &cipher_suites)) == NULL) 998 goto err; 999 } 1000 1001 /* If it is a hit, check that the cipher is in the list */ 1002 /* XXX - CBS_len(&cipher_suites) will always be zero here... */ 1003 if (s->internal->hit && CBS_len(&cipher_suites) > 0) { 1004 j = 0; 1005 id = s->session->cipher->id; 1006 1007 for (i = 0; i < sk_SSL_CIPHER_num(ciphers); i++) { 1008 c = sk_SSL_CIPHER_value(ciphers, i); 1009 if (c->id == id) { 1010 j = 1; 1011 break; 1012 } 1013 } 1014 if (j == 0) { 1015 /* 1016 * We need to have the cipher in the cipher 1017 * list if we are asked to reuse it 1018 */ 1019 al = SSL_AD_ILLEGAL_PARAMETER; 1020 SSLerror(s, SSL_R_REQUIRED_CIPHER_MISSING); 1021 goto f_err; 1022 } 1023 } 1024 1025 comp_null = 0; 1026 while (CBS_len(&compression_methods) > 0) { 1027 if (!CBS_get_u8(&compression_methods, &comp_method)) 1028 goto truncated; 1029 if (comp_method == 0) 1030 comp_null = 1; 1031 } 1032 if (comp_null == 0) { 1033 al = SSL_AD_DECODE_ERROR; 1034 SSLerror(s, SSL_R_NO_COMPRESSION_SPECIFIED); 1035 goto f_err; 1036 } 1037 1038 if (!tlsext_clienthello_parse(s, &cbs, &al)) { 1039 SSLerror(s, SSL_R_PARSE_TLSEXT); 1040 goto f_err; 1041 } 1042 1043 if (!S3I(s)->renegotiate_seen && s->internal->renegotiate) { 1044 al = SSL_AD_HANDSHAKE_FAILURE; 1045 SSLerror(s, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED); 1046 goto f_err; 1047 } 1048 1049 if (ssl_check_clienthello_tlsext_early(s) <= 0) { 1050 SSLerror(s, SSL_R_CLIENTHELLO_TLSEXT); 1051 goto err; 1052 } 1053 1054 /* 1055 * Check if we want to use external pre-shared secret for this 1056 * handshake for not reused session only. We need to generate 1057 * server_random before calling tls_session_secret_cb in order to allow 1058 * SessionTicket processing to use it in key derivation. 1059 */ 1060 arc4random_buf(s->s3->server_random, SSL3_RANDOM_SIZE); 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 f_err; 1083 } 1084 1085 s->session->cipher = pref_cipher; 1086 1087 sk_SSL_CIPHER_free(s->cipher_list); 1088 sk_SSL_CIPHER_free(s->internal->cipher_list_by_id); 1089 1090 s->cipher_list = sk_SSL_CIPHER_dup(s->session->ciphers); 1091 s->internal->cipher_list_by_id = 1092 sk_SSL_CIPHER_dup(s->session->ciphers); 1093 } 1094 } 1095 1096 /* 1097 * Given s->session->ciphers and SSL_get_ciphers, we must 1098 * pick a cipher 1099 */ 1100 1101 if (!s->internal->hit) { 1102 sk_SSL_CIPHER_free(s->session->ciphers); 1103 s->session->ciphers = ciphers; 1104 if (ciphers == NULL) { 1105 al = SSL_AD_ILLEGAL_PARAMETER; 1106 SSLerror(s, SSL_R_NO_CIPHERS_PASSED); 1107 goto f_err; 1108 } 1109 ciphers = NULL; 1110 c = ssl3_choose_cipher(s, s->session->ciphers, 1111 SSL_get_ciphers(s)); 1112 1113 if (c == NULL) { 1114 al = SSL_AD_HANDSHAKE_FAILURE; 1115 SSLerror(s, SSL_R_NO_SHARED_CIPHER); 1116 goto f_err; 1117 } 1118 S3I(s)->hs.new_cipher = c; 1119 } else { 1120 S3I(s)->hs.new_cipher = s->session->cipher; 1121 } 1122 1123 if (!tls1_handshake_hash_init(s)) 1124 goto err; 1125 1126 alg_k = S3I(s)->hs.new_cipher->algorithm_mkey; 1127 if (!(SSL_USE_SIGALGS(s) || (alg_k & SSL_kGOST)) || 1128 !(s->verify_mode & SSL_VERIFY_PEER)) { 1129 if (!tls1_digest_cached_records(s)) { 1130 al = SSL_AD_INTERNAL_ERROR; 1131 goto f_err; 1132 } 1133 } 1134 1135 /* 1136 * We now have the following setup. 1137 * client_random 1138 * cipher_list - our prefered list of ciphers 1139 * ciphers - the clients prefered list of ciphers 1140 * compression - basically ignored right now 1141 * ssl version is set - sslv3 1142 * s->session - The ssl session has been setup. 1143 * s->internal->hit - session reuse flag 1144 * s->hs.new_cipher - the new cipher to use. 1145 */ 1146 1147 /* Handles TLS extensions that we couldn't check earlier */ 1148 if (ssl_check_clienthello_tlsext_late(s) <= 0) { 1149 SSLerror(s, SSL_R_CLIENTHELLO_TLSEXT); 1150 goto err; 1151 } 1152 1153 ret = cookie_valid ? 2 : 1; 1154 1155 if (0) { 1156 truncated: 1157 al = SSL_AD_DECODE_ERROR; 1158 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 1159 f_err: 1160 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1161 } 1162 err: 1163 sk_SSL_CIPHER_free(ciphers); 1164 1165 return (ret); 1166 } 1167 1168 int 1169 ssl3_send_server_hello(SSL *s) 1170 { 1171 CBB cbb, server_hello, session_id; 1172 size_t sl; 1173 1174 memset(&cbb, 0, sizeof(cbb)); 1175 1176 if (S3I(s)->hs.state == SSL3_ST_SW_SRVR_HELLO_A) { 1177 if (!ssl3_handshake_msg_start(s, &cbb, &server_hello, 1178 SSL3_MT_SERVER_HELLO)) 1179 goto err; 1180 1181 if (!CBB_add_u16(&server_hello, s->version)) 1182 goto err; 1183 if (!CBB_add_bytes(&server_hello, s->s3->server_random, 1184 sizeof(s->s3->server_random))) 1185 goto err; 1186 1187 /* 1188 * There are several cases for the session ID to send 1189 * back in the server hello: 1190 * 1191 * - For session reuse from the session cache, 1192 * we send back the old session ID. 1193 * - If stateless session reuse (using a session ticket) 1194 * is successful, we send back the client's "session ID" 1195 * (which doesn't actually identify the session). 1196 * - If it is a new session, we send back the new 1197 * session ID. 1198 * - However, if we want the new session to be single-use, 1199 * we send back a 0-length session ID. 1200 * 1201 * s->internal->hit is non-zero in either case of session reuse, 1202 * so the following won't overwrite an ID that we're supposed 1203 * to send back. 1204 */ 1205 if (!(s->ctx->internal->session_cache_mode & SSL_SESS_CACHE_SERVER) 1206 && !s->internal->hit) 1207 s->session->session_id_length = 0; 1208 1209 sl = s->session->session_id_length; 1210 if (sl > sizeof(s->session->session_id)) { 1211 SSLerror(s, ERR_R_INTERNAL_ERROR); 1212 goto err; 1213 } 1214 if (!CBB_add_u8_length_prefixed(&server_hello, &session_id)) 1215 goto err; 1216 if (!CBB_add_bytes(&session_id, s->session->session_id, sl)) 1217 goto err; 1218 1219 /* Cipher suite. */ 1220 if (!CBB_add_u16(&server_hello, 1221 ssl3_cipher_get_value(S3I(s)->hs.new_cipher))) 1222 goto err; 1223 1224 /* Compression method (null). */ 1225 if (!CBB_add_u8(&server_hello, 0)) 1226 goto err; 1227 1228 /* TLS extensions */ 1229 if (!tlsext_serverhello_build(s, &server_hello)) { 1230 SSLerror(s, ERR_R_INTERNAL_ERROR); 1231 goto err; 1232 } 1233 1234 if (!ssl3_handshake_msg_finish(s, &cbb)) 1235 goto err; 1236 } 1237 1238 /* SSL3_ST_SW_SRVR_HELLO_B */ 1239 return (ssl3_handshake_write(s)); 1240 1241 err: 1242 CBB_cleanup(&cbb); 1243 1244 return (-1); 1245 } 1246 1247 int 1248 ssl3_send_server_done(SSL *s) 1249 { 1250 CBB cbb, done; 1251 1252 memset(&cbb, 0, sizeof(cbb)); 1253 1254 if (S3I(s)->hs.state == SSL3_ST_SW_SRVR_DONE_A) { 1255 if (!ssl3_handshake_msg_start(s, &cbb, &done, 1256 SSL3_MT_SERVER_DONE)) 1257 goto err; 1258 if (!ssl3_handshake_msg_finish(s, &cbb)) 1259 goto err; 1260 1261 S3I(s)->hs.state = SSL3_ST_SW_SRVR_DONE_B; 1262 } 1263 1264 /* SSL3_ST_SW_SRVR_DONE_B */ 1265 return (ssl3_handshake_write(s)); 1266 1267 err: 1268 CBB_cleanup(&cbb); 1269 1270 return (-1); 1271 } 1272 1273 static int 1274 ssl3_send_server_kex_dhe(SSL *s, CBB *cbb) 1275 { 1276 CBB dh_p, dh_g, dh_Ys; 1277 DH *dh = NULL, *dhp; 1278 unsigned char *data; 1279 int al; 1280 1281 if (s->cert->dh_tmp_auto != 0) { 1282 if ((dhp = ssl_get_auto_dh(s)) == NULL) { 1283 al = SSL_AD_INTERNAL_ERROR; 1284 SSLerror(s, ERR_R_INTERNAL_ERROR); 1285 goto f_err; 1286 } 1287 } else 1288 dhp = s->cert->dh_tmp; 1289 1290 if (dhp == NULL && s->cert->dh_tmp_cb != NULL) 1291 dhp = s->cert->dh_tmp_cb(s, 0, 1292 SSL_C_PKEYLENGTH(S3I(s)->hs.new_cipher)); 1293 1294 if (dhp == NULL) { 1295 al = SSL_AD_HANDSHAKE_FAILURE; 1296 SSLerror(s, SSL_R_MISSING_TMP_DH_KEY); 1297 goto f_err; 1298 } 1299 1300 if (S3I(s)->tmp.dh != NULL) { 1301 SSLerror(s, ERR_R_INTERNAL_ERROR); 1302 goto err; 1303 } 1304 1305 if (s->cert->dh_tmp_auto != 0) { 1306 dh = dhp; 1307 } else if ((dh = DHparams_dup(dhp)) == NULL) { 1308 SSLerror(s, ERR_R_DH_LIB); 1309 goto err; 1310 } 1311 S3I(s)->tmp.dh = dh; 1312 if (!DH_generate_key(dh)) { 1313 SSLerror(s, ERR_R_DH_LIB); 1314 goto err; 1315 } 1316 1317 /* 1318 * Serialize the DH parameters and public key. 1319 */ 1320 if (!CBB_add_u16_length_prefixed(cbb, &dh_p)) 1321 goto err; 1322 if (!CBB_add_space(&dh_p, &data, BN_num_bytes(dh->p))) 1323 goto err; 1324 BN_bn2bin(dh->p, data); 1325 1326 if (!CBB_add_u16_length_prefixed(cbb, &dh_g)) 1327 goto err; 1328 if (!CBB_add_space(&dh_g, &data, BN_num_bytes(dh->g))) 1329 goto err; 1330 BN_bn2bin(dh->g, data); 1331 1332 if (!CBB_add_u16_length_prefixed(cbb, &dh_Ys)) 1333 goto err; 1334 if (!CBB_add_space(&dh_Ys, &data, BN_num_bytes(dh->pub_key))) 1335 goto err; 1336 BN_bn2bin(dh->pub_key, data); 1337 1338 if (!CBB_flush(cbb)) 1339 goto err; 1340 1341 return (1); 1342 1343 f_err: 1344 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1345 err: 1346 return (-1); 1347 } 1348 1349 static int 1350 ssl3_send_server_kex_ecdhe_ecp(SSL *s, int nid, CBB *cbb) 1351 { 1352 const EC_GROUP *group; 1353 const EC_POINT *pubkey; 1354 unsigned char *data; 1355 int encoded_len = 0; 1356 int curve_id = 0; 1357 BN_CTX *bn_ctx = NULL; 1358 EC_KEY *ecdh; 1359 CBB ecpoint; 1360 int al; 1361 1362 /* 1363 * Only named curves are supported in ECDH ephemeral key exchanges. 1364 * For supported named curves, curve_id is non-zero. 1365 */ 1366 if ((curve_id = tls1_ec_nid2curve_id(nid)) == 0) { 1367 SSLerror(s, SSL_R_UNSUPPORTED_ELLIPTIC_CURVE); 1368 goto err; 1369 } 1370 1371 if (S3I(s)->tmp.ecdh != NULL) { 1372 SSLerror(s, ERR_R_INTERNAL_ERROR); 1373 goto err; 1374 } 1375 1376 if ((S3I(s)->tmp.ecdh = EC_KEY_new_by_curve_name(nid)) == NULL) { 1377 al = SSL_AD_HANDSHAKE_FAILURE; 1378 SSLerror(s, SSL_R_MISSING_TMP_ECDH_KEY); 1379 goto f_err; 1380 } 1381 ecdh = S3I(s)->tmp.ecdh; 1382 1383 if (!EC_KEY_generate_key(ecdh)) { 1384 SSLerror(s, ERR_R_ECDH_LIB); 1385 goto err; 1386 } 1387 if ((group = EC_KEY_get0_group(ecdh)) == NULL || 1388 (pubkey = EC_KEY_get0_public_key(ecdh)) == NULL || 1389 EC_KEY_get0_private_key(ecdh) == NULL) { 1390 SSLerror(s, ERR_R_ECDH_LIB); 1391 goto err; 1392 } 1393 1394 /* 1395 * Encode the public key. 1396 */ 1397 encoded_len = EC_POINT_point2oct(group, pubkey, 1398 POINT_CONVERSION_UNCOMPRESSED, NULL, 0, NULL); 1399 if (encoded_len == 0) { 1400 SSLerror(s, ERR_R_ECDH_LIB); 1401 goto err; 1402 } 1403 if ((bn_ctx = BN_CTX_new()) == NULL) { 1404 SSLerror(s, ERR_R_MALLOC_FAILURE); 1405 goto err; 1406 } 1407 1408 /* 1409 * Only named curves are supported in ECDH ephemeral key exchanges. 1410 * In this case the ServerKeyExchange message has: 1411 * [1 byte CurveType], [2 byte CurveName] 1412 * [1 byte length of encoded point], followed by 1413 * the actual encoded point itself. 1414 */ 1415 if (!CBB_add_u8(cbb, NAMED_CURVE_TYPE)) 1416 goto err; 1417 if (!CBB_add_u16(cbb, curve_id)) 1418 goto err; 1419 if (!CBB_add_u8_length_prefixed(cbb, &ecpoint)) 1420 goto err; 1421 if (!CBB_add_space(&ecpoint, &data, encoded_len)) 1422 goto err; 1423 if (EC_POINT_point2oct(group, pubkey, POINT_CONVERSION_UNCOMPRESSED, 1424 data, encoded_len, bn_ctx) == 0) { 1425 SSLerror(s, ERR_R_ECDH_LIB); 1426 goto err; 1427 } 1428 if (!CBB_flush(cbb)) 1429 goto err; 1430 1431 BN_CTX_free(bn_ctx); 1432 1433 return (1); 1434 1435 f_err: 1436 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1437 err: 1438 BN_CTX_free(bn_ctx); 1439 1440 return (-1); 1441 } 1442 1443 static int 1444 ssl3_send_server_kex_ecdhe_ecx(SSL *s, int nid, CBB *cbb) 1445 { 1446 uint8_t *public_key = NULL; 1447 int curve_id; 1448 CBB ecpoint; 1449 int ret = -1; 1450 1451 /* Generate an X25519 key pair. */ 1452 if (S3I(s)->tmp.x25519 != NULL) { 1453 SSLerror(s, ERR_R_INTERNAL_ERROR); 1454 goto err; 1455 } 1456 if ((S3I(s)->tmp.x25519 = malloc(X25519_KEY_LENGTH)) == NULL) 1457 goto err; 1458 if ((public_key = malloc(X25519_KEY_LENGTH)) == NULL) 1459 goto err; 1460 X25519_keypair(public_key, S3I(s)->tmp.x25519); 1461 1462 /* Serialize public key. */ 1463 if ((curve_id = tls1_ec_nid2curve_id(nid)) == 0) { 1464 SSLerror(s, SSL_R_UNSUPPORTED_ELLIPTIC_CURVE); 1465 goto err; 1466 } 1467 1468 if (!CBB_add_u8(cbb, NAMED_CURVE_TYPE)) 1469 goto err; 1470 if (!CBB_add_u16(cbb, curve_id)) 1471 goto err; 1472 if (!CBB_add_u8_length_prefixed(cbb, &ecpoint)) 1473 goto err; 1474 if (!CBB_add_bytes(&ecpoint, public_key, X25519_KEY_LENGTH)) 1475 goto err; 1476 if (!CBB_flush(cbb)) 1477 goto err; 1478 1479 ret = 1; 1480 1481 err: 1482 free(public_key); 1483 1484 return (ret); 1485 } 1486 1487 static int 1488 ssl3_send_server_kex_ecdhe(SSL *s, CBB *cbb) 1489 { 1490 int nid; 1491 1492 nid = tls1_get_shared_curve(s); 1493 1494 if (nid == NID_X25519) 1495 return ssl3_send_server_kex_ecdhe_ecx(s, nid, cbb); 1496 1497 return ssl3_send_server_kex_ecdhe_ecp(s, nid, cbb); 1498 } 1499 1500 int 1501 ssl3_send_server_key_exchange(SSL *s) 1502 { 1503 CBB cbb, cbb_params, cbb_signature, server_kex; 1504 unsigned char *signature = NULL; 1505 unsigned int signature_len; 1506 unsigned char *params = NULL; 1507 size_t params_len; 1508 const EVP_MD *md = NULL; 1509 unsigned long type; 1510 EVP_MD_CTX md_ctx; 1511 EVP_PKEY *pkey; 1512 int al; 1513 1514 memset(&cbb, 0, sizeof(cbb)); 1515 memset(&cbb_params, 0, sizeof(cbb_params)); 1516 1517 EVP_MD_CTX_init(&md_ctx); 1518 1519 if (S3I(s)->hs.state == SSL3_ST_SW_KEY_EXCH_A) { 1520 1521 if (!ssl3_handshake_msg_start(s, &cbb, &server_kex, 1522 SSL3_MT_SERVER_KEY_EXCHANGE)) 1523 goto err; 1524 1525 if (!CBB_init(&cbb_params, 0)) 1526 goto err; 1527 1528 type = S3I(s)->hs.new_cipher->algorithm_mkey; 1529 if (type & SSL_kDHE) { 1530 if (ssl3_send_server_kex_dhe(s, &cbb_params) != 1) 1531 goto err; 1532 } else if (type & SSL_kECDHE) { 1533 if (ssl3_send_server_kex_ecdhe(s, &cbb_params) != 1) 1534 goto err; 1535 } else { 1536 al = SSL_AD_HANDSHAKE_FAILURE; 1537 SSLerror(s, SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE); 1538 goto f_err; 1539 } 1540 1541 if (!CBB_finish(&cbb_params, ¶ms, ¶ms_len)) 1542 goto err; 1543 1544 if (!CBB_add_bytes(&server_kex, params, params_len)) 1545 goto err; 1546 1547 /* Add signature unless anonymous. */ 1548 if (!(S3I(s)->hs.new_cipher->algorithm_auth & SSL_aNULL)) { 1549 if ((pkey = ssl_get_sign_pkey(s, S3I(s)->hs.new_cipher, 1550 &md)) == NULL) { 1551 al = SSL_AD_DECODE_ERROR; 1552 goto f_err; 1553 } 1554 1555 if (pkey->type == EVP_PKEY_RSA && !SSL_USE_SIGALGS(s)) 1556 md = EVP_md5_sha1(); 1557 1558 if (md == NULL) { 1559 /* Is this error check actually needed? */ 1560 al = SSL_AD_HANDSHAKE_FAILURE; 1561 SSLerror(s, SSL_R_UNKNOWN_PKEY_TYPE); 1562 goto f_err; 1563 } 1564 1565 /* Send signature algorithm. */ 1566 if (SSL_USE_SIGALGS(s)) { 1567 if (!tls12_get_hashandsig(&server_kex, pkey, md)) { 1568 /* Should never happen */ 1569 al = SSL_AD_INTERNAL_ERROR; 1570 SSLerror(s, ERR_R_INTERNAL_ERROR); 1571 goto f_err; 1572 } 1573 } 1574 1575 if ((signature = calloc(1, EVP_PKEY_size(pkey))) == NULL) 1576 goto err; 1577 1578 if (!EVP_SignInit_ex(&md_ctx, md, NULL)) 1579 goto err; 1580 if (!EVP_SignUpdate(&md_ctx, s->s3->client_random, 1581 SSL3_RANDOM_SIZE)) 1582 goto err; 1583 if (!EVP_SignUpdate(&md_ctx, s->s3->server_random, 1584 SSL3_RANDOM_SIZE)) 1585 goto err; 1586 if (!EVP_SignUpdate(&md_ctx, params, params_len)) 1587 goto err; 1588 if (!EVP_SignFinal(&md_ctx, signature, &signature_len, 1589 pkey)) { 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 f_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 unsigned char *sigalgs_data; 1652 size_t sigalgs_len; 1653 1654 tls12_get_req_sig_algs(s, &sigalgs_data, &sigalgs_len); 1655 1656 if (!CBB_add_u16_length_prefixed(&cert_request, &sigalgs)) 1657 goto err; 1658 if (!CBB_add_bytes(&sigalgs, sigalgs_data, sigalgs_len)) 1659 goto err; 1660 } 1661 1662 if (!CBB_add_u16_length_prefixed(&cert_request, &cert_auth)) 1663 goto err; 1664 1665 sk = SSL_get_client_CA_list(s); 1666 for (i = 0; i < sk_X509_NAME_num(sk); i++) { 1667 unsigned char *name_data; 1668 size_t name_len; 1669 1670 name = sk_X509_NAME_value(sk, i); 1671 name_len = i2d_X509_NAME(name, NULL); 1672 1673 if (!CBB_add_u16_length_prefixed(&cert_auth, &dn)) 1674 goto err; 1675 if (!CBB_add_space(&dn, &name_data, name_len)) 1676 goto err; 1677 if (i2d_X509_NAME(name, &name_data) != name_len) 1678 goto err; 1679 } 1680 1681 if (!ssl3_handshake_msg_finish(s, &cbb)) 1682 goto err; 1683 1684 S3I(s)->hs.state = SSL3_ST_SW_CERT_REQ_B; 1685 } 1686 1687 /* SSL3_ST_SW_CERT_REQ_B */ 1688 return (ssl3_handshake_write(s)); 1689 1690 err: 1691 CBB_cleanup(&cbb); 1692 1693 return (-1); 1694 } 1695 1696 static int 1697 ssl3_get_client_kex_rsa(SSL *s, CBS *cbs) 1698 { 1699 unsigned char fakekey[SSL_MAX_MASTER_KEY_LENGTH]; 1700 unsigned char *pms = NULL; 1701 unsigned char *p; 1702 size_t pms_len = 0; 1703 EVP_PKEY *pkey = NULL; 1704 RSA *rsa = NULL; 1705 CBS enc_pms; 1706 int decrypt_len; 1707 int al = -1; 1708 1709 arc4random_buf(fakekey, sizeof(fakekey)); 1710 fakekey[0] = s->client_version >> 8; 1711 fakekey[1] = s->client_version & 0xff; 1712 1713 pkey = s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey; 1714 if ((pkey == NULL) || (pkey->type != EVP_PKEY_RSA) || 1715 (pkey->pkey.rsa == NULL)) { 1716 al = SSL_AD_HANDSHAKE_FAILURE; 1717 SSLerror(s, SSL_R_MISSING_RSA_CERTIFICATE); 1718 goto f_err; 1719 } 1720 rsa = pkey->pkey.rsa; 1721 1722 pms_len = RSA_size(rsa); 1723 if (pms_len < SSL_MAX_MASTER_KEY_LENGTH) 1724 goto err; 1725 if ((pms = malloc(pms_len)) == NULL) 1726 goto err; 1727 p = pms; 1728 1729 if (!CBS_get_u16_length_prefixed(cbs, &enc_pms)) 1730 goto truncated; 1731 if (CBS_len(cbs) != 0 || CBS_len(&enc_pms) != RSA_size(rsa)) { 1732 SSLerror(s, SSL_R_TLS_RSA_ENCRYPTED_VALUE_LENGTH_IS_WRONG); 1733 goto err; 1734 } 1735 1736 decrypt_len = RSA_private_decrypt(CBS_len(&enc_pms), CBS_data(&enc_pms), 1737 pms, rsa, RSA_PKCS1_PADDING); 1738 1739 ERR_clear_error(); 1740 1741 if (decrypt_len != SSL_MAX_MASTER_KEY_LENGTH) { 1742 al = SSL_AD_DECODE_ERROR; 1743 /* SSLerror(s, SSL_R_BAD_RSA_DECRYPT); */ 1744 } 1745 1746 if ((al == -1) && !((pms[0] == (s->client_version >> 8)) && 1747 (pms[1] == (s->client_version & 0xff)))) { 1748 /* 1749 * The premaster secret must contain the same version number 1750 * as the ClientHello to detect version rollback attacks 1751 * (strangely, the protocol does not offer such protection for 1752 * DH ciphersuites). 1753 * 1754 * The Klima-Pokorny-Rosa extension of Bleichenbacher's attack 1755 * (http://eprint.iacr.org/2003/052/) exploits the version 1756 * number check as a "bad version oracle" -- an alert would 1757 * reveal that the plaintext corresponding to some ciphertext 1758 * made up by the adversary is properly formatted except that 1759 * the version number is wrong. To avoid such attacks, we should 1760 * treat this just like any other decryption error. 1761 */ 1762 al = SSL_AD_DECODE_ERROR; 1763 /* SSLerror(s, SSL_R_BAD_PROTOCOL_VERSION_NUMBER); */ 1764 } 1765 1766 if (al != -1) { 1767 /* 1768 * Some decryption failure -- use random value instead 1769 * as countermeasure against Bleichenbacher's attack 1770 * on PKCS #1 v1.5 RSA padding (see RFC 2246, 1771 * section 7.4.7.1). 1772 */ 1773 p = fakekey; 1774 } 1775 1776 s->session->master_key_length = 1777 tls1_generate_master_secret(s, 1778 s->session->master_key, p, SSL_MAX_MASTER_KEY_LENGTH); 1779 1780 freezero(pms, pms_len); 1781 1782 return (1); 1783 1784 truncated: 1785 al = SSL_AD_DECODE_ERROR; 1786 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 1787 f_err: 1788 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1789 err: 1790 freezero(pms, pms_len); 1791 1792 return (-1); 1793 } 1794 1795 static int 1796 ssl3_get_client_kex_dhe(SSL *s, CBS *cbs) 1797 { 1798 int key_size = 0, key_len, al; 1799 unsigned char *key = NULL; 1800 BIGNUM *bn = NULL; 1801 CBS dh_Yc; 1802 DH *dh; 1803 1804 if (!CBS_get_u16_length_prefixed(cbs, &dh_Yc)) 1805 goto truncated; 1806 if (CBS_len(cbs) != 0) 1807 goto truncated; 1808 1809 if (S3I(s)->tmp.dh == NULL) { 1810 al = SSL_AD_HANDSHAKE_FAILURE; 1811 SSLerror(s, SSL_R_MISSING_TMP_DH_KEY); 1812 goto f_err; 1813 } 1814 dh = S3I(s)->tmp.dh; 1815 1816 if ((bn = BN_bin2bn(CBS_data(&dh_Yc), CBS_len(&dh_Yc), NULL)) == NULL) { 1817 SSLerror(s, SSL_R_BN_LIB); 1818 goto err; 1819 } 1820 1821 if ((key_size = DH_size(dh)) <= 0) { 1822 SSLerror(s, ERR_R_DH_LIB); 1823 goto err; 1824 } 1825 if ((key = malloc(key_size)) == NULL) { 1826 SSLerror(s, ERR_R_MALLOC_FAILURE); 1827 goto err; 1828 } 1829 if ((key_len = DH_compute_key(key, bn, dh)) <= 0) { 1830 SSLerror(s, ERR_R_DH_LIB); 1831 goto err; 1832 } 1833 1834 s->session->master_key_length = tls1_generate_master_secret(s, 1835 s->session->master_key, key, key_len); 1836 1837 DH_free(S3I(s)->tmp.dh); 1838 S3I(s)->tmp.dh = NULL; 1839 1840 freezero(key, key_size); 1841 BN_clear_free(bn); 1842 1843 return (1); 1844 1845 truncated: 1846 al = SSL_AD_DECODE_ERROR; 1847 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 1848 f_err: 1849 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1850 err: 1851 freezero(key, key_size); 1852 BN_clear_free(bn); 1853 1854 return (-1); 1855 } 1856 1857 static int 1858 ssl3_get_client_kex_ecdhe_ecp(SSL *s, CBS *cbs) 1859 { 1860 unsigned char *key = NULL; 1861 int key_size = 0, key_len; 1862 EC_POINT *point = NULL; 1863 BN_CTX *bn_ctx = NULL; 1864 const EC_GROUP *group; 1865 EC_KEY *ecdh; 1866 CBS public; 1867 int ret = -1; 1868 1869 if (!CBS_get_u8_length_prefixed(cbs, &public)) 1870 goto err; 1871 if (CBS_len(cbs) != 0) 1872 goto err; 1873 1874 /* 1875 * Use the ephemeral values we saved when generating the 1876 * ServerKeyExchange message. 1877 */ 1878 if ((ecdh = S3I(s)->tmp.ecdh) == NULL) { 1879 SSLerror(s, ERR_R_INTERNAL_ERROR); 1880 goto err; 1881 } 1882 group = EC_KEY_get0_group(ecdh); 1883 1884 /* 1885 * Get client's public key from encoded point in the ClientKeyExchange 1886 * message. 1887 */ 1888 if ((bn_ctx = BN_CTX_new()) == NULL) { 1889 SSLerror(s, ERR_R_MALLOC_FAILURE); 1890 goto err; 1891 } 1892 if ((point = EC_POINT_new(group)) == NULL) { 1893 SSLerror(s, ERR_R_MALLOC_FAILURE); 1894 goto err; 1895 } 1896 if (EC_POINT_oct2point(group, point, CBS_data(&public), 1897 CBS_len(&public), bn_ctx) == 0) { 1898 SSLerror(s, ERR_R_EC_LIB); 1899 goto err; 1900 } 1901 1902 /* Compute the shared pre-master secret */ 1903 if ((key_size = ECDH_size(ecdh)) <= 0) { 1904 SSLerror(s, ERR_R_ECDH_LIB); 1905 goto err; 1906 } 1907 if ((key = malloc(key_size)) == NULL) { 1908 SSLerror(s, ERR_R_MALLOC_FAILURE); 1909 goto err; 1910 } 1911 if ((key_len = ECDH_compute_key(key, key_size, point, ecdh, 1912 NULL)) <= 0) { 1913 SSLerror(s, ERR_R_ECDH_LIB); 1914 goto err; 1915 } 1916 1917 /* Compute the master secret */ 1918 s->session->master_key_length = tls1_generate_master_secret(s, 1919 s->session->master_key, key, key_len); 1920 1921 EC_KEY_free(S3I(s)->tmp.ecdh); 1922 S3I(s)->tmp.ecdh = NULL; 1923 1924 ret = 1; 1925 1926 err: 1927 freezero(key, key_size); 1928 EC_POINT_free(point); 1929 BN_CTX_free(bn_ctx); 1930 1931 return (ret); 1932 } 1933 1934 static int 1935 ssl3_get_client_kex_ecdhe_ecx(SSL *s, CBS *cbs) 1936 { 1937 uint8_t *shared_key = NULL; 1938 CBS ecpoint; 1939 int ret = -1; 1940 1941 if (!CBS_get_u8_length_prefixed(cbs, &ecpoint)) 1942 goto err; 1943 if (CBS_len(cbs) != 0) 1944 goto err; 1945 if (CBS_len(&ecpoint) != X25519_KEY_LENGTH) 1946 goto err; 1947 1948 if ((shared_key = malloc(X25519_KEY_LENGTH)) == NULL) 1949 goto err; 1950 if (!X25519(shared_key, S3I(s)->tmp.x25519, CBS_data(&ecpoint))) 1951 goto err; 1952 1953 freezero(S3I(s)->tmp.x25519, X25519_KEY_LENGTH); 1954 S3I(s)->tmp.x25519 = NULL; 1955 1956 s->session->master_key_length = 1957 tls1_generate_master_secret( 1958 s, s->session->master_key, shared_key, X25519_KEY_LENGTH); 1959 1960 ret = 1; 1961 1962 err: 1963 freezero(shared_key, X25519_KEY_LENGTH); 1964 1965 return (ret); 1966 } 1967 1968 static int 1969 ssl3_get_client_kex_ecdhe(SSL *s, CBS *cbs) 1970 { 1971 if (S3I(s)->tmp.x25519 != NULL) 1972 return ssl3_get_client_kex_ecdhe_ecx(s, cbs); 1973 1974 return ssl3_get_client_kex_ecdhe_ecp(s, cbs); 1975 } 1976 1977 static int 1978 ssl3_get_client_kex_gost(SSL *s, CBS *cbs) 1979 { 1980 EVP_PKEY_CTX *pkey_ctx; 1981 EVP_PKEY *client_pub_pkey = NULL, *pk = NULL; 1982 unsigned char premaster_secret[32]; 1983 unsigned long alg_a; 1984 size_t outlen = 32; 1985 CBS gostblob; 1986 int al; 1987 int ret = 0; 1988 1989 /* Get our certificate private key*/ 1990 alg_a = S3I(s)->hs.new_cipher->algorithm_auth; 1991 if (alg_a & SSL_aGOST01) 1992 pk = s->cert->pkeys[SSL_PKEY_GOST01].privatekey; 1993 1994 if ((pkey_ctx = EVP_PKEY_CTX_new(pk, NULL)) == NULL) 1995 goto err; 1996 if (EVP_PKEY_decrypt_init(pkey_ctx) <= 0) 1997 goto gerr; 1998 1999 /* 2000 * If client certificate is present and is of the same type, 2001 * maybe use it for key exchange. 2002 * Don't mind errors from EVP_PKEY_derive_set_peer, because 2003 * it is completely valid to use a client certificate for 2004 * authorization only. 2005 */ 2006 if ((client_pub_pkey = X509_get_pubkey(s->session->peer)) != NULL) { 2007 if (EVP_PKEY_derive_set_peer(pkey_ctx, 2008 client_pub_pkey) <= 0) 2009 ERR_clear_error(); 2010 } 2011 2012 /* Decrypt session key */ 2013 if (!CBS_get_asn1(cbs, &gostblob, CBS_ASN1_SEQUENCE)) 2014 goto truncated; 2015 if (CBS_len(cbs) != 0) 2016 goto truncated; 2017 if (EVP_PKEY_decrypt(pkey_ctx, premaster_secret, &outlen, 2018 CBS_data(&gostblob), CBS_len(&gostblob)) <= 0) { 2019 SSLerror(s, SSL_R_DECRYPTION_FAILED); 2020 goto gerr; 2021 } 2022 2023 /* Generate master secret */ 2024 s->session->master_key_length = 2025 tls1_generate_master_secret( 2026 s, s->session->master_key, premaster_secret, 32); 2027 2028 /* Check if pubkey from client certificate was used */ 2029 if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, -1, 2030 EVP_PKEY_CTRL_PEER_KEY, 2, NULL) > 0) 2031 ret = 2; 2032 else 2033 ret = 1; 2034 gerr: 2035 EVP_PKEY_free(client_pub_pkey); 2036 EVP_PKEY_CTX_free(pkey_ctx); 2037 if (ret) 2038 return (ret); 2039 else 2040 goto err; 2041 2042 truncated: 2043 al = SSL_AD_DECODE_ERROR; 2044 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 2045 ssl3_send_alert(s, SSL3_AL_FATAL, al); 2046 err: 2047 return (-1); 2048 } 2049 2050 int 2051 ssl3_get_client_key_exchange(SSL *s) 2052 { 2053 unsigned long alg_k; 2054 int al, ok; 2055 CBS cbs; 2056 long n; 2057 2058 /* 2048 maxlen is a guess. How long a key does that permit? */ 2059 n = s->method->internal->ssl_get_message(s, SSL3_ST_SR_KEY_EXCH_A, 2060 SSL3_ST_SR_KEY_EXCH_B, SSL3_MT_CLIENT_KEY_EXCHANGE, 2048, &ok); 2061 if (!ok) 2062 return ((int)n); 2063 2064 if (n < 0) 2065 goto err; 2066 2067 CBS_init(&cbs, s->internal->init_msg, n); 2068 2069 alg_k = S3I(s)->hs.new_cipher->algorithm_mkey; 2070 2071 if (alg_k & SSL_kRSA) { 2072 if (ssl3_get_client_kex_rsa(s, &cbs) != 1) 2073 goto err; 2074 } else if (alg_k & SSL_kDHE) { 2075 if (ssl3_get_client_kex_dhe(s, &cbs) != 1) 2076 goto err; 2077 } else if (alg_k & SSL_kECDHE) { 2078 if (ssl3_get_client_kex_ecdhe(s, &cbs) != 1) 2079 goto err; 2080 } else if (alg_k & SSL_kGOST) { 2081 if (ssl3_get_client_kex_gost(s, &cbs) != 1) 2082 goto err; 2083 } else { 2084 al = SSL_AD_HANDSHAKE_FAILURE; 2085 SSLerror(s, SSL_R_UNKNOWN_CIPHER_TYPE); 2086 goto f_err; 2087 } 2088 2089 if (CBS_len(&cbs) != 0) { 2090 al = SSL_AD_DECODE_ERROR; 2091 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 2092 goto f_err; 2093 } 2094 2095 return (1); 2096 2097 f_err: 2098 ssl3_send_alert(s, SSL3_AL_FATAL, al); 2099 err: 2100 return (-1); 2101 } 2102 2103 int 2104 ssl3_get_cert_verify(SSL *s) 2105 { 2106 CBS cbs, signature; 2107 const EVP_MD *md = NULL; 2108 EVP_PKEY *pkey = NULL; 2109 X509 *peer = NULL; 2110 EVP_MD_CTX mctx; 2111 uint8_t hash_id, sig_id; 2112 int al, ok, sigalg, verify; 2113 int type = 0; 2114 int ret = 0; 2115 long hdatalen; 2116 void *hdata; 2117 long n; 2118 2119 EVP_MD_CTX_init(&mctx); 2120 2121 n = s->method->internal->ssl_get_message(s, SSL3_ST_SR_CERT_VRFY_A, 2122 SSL3_ST_SR_CERT_VRFY_B, -1, SSL3_RT_MAX_PLAIN_LENGTH, &ok); 2123 if (!ok) 2124 return ((int)n); 2125 2126 if (n < 0) 2127 goto err; 2128 2129 CBS_init(&cbs, s->internal->init_msg, n); 2130 2131 if (s->session->peer != NULL) { 2132 peer = s->session->peer; 2133 pkey = X509_get_pubkey(peer); 2134 type = X509_certificate_type(peer, pkey); 2135 } 2136 2137 if (S3I(s)->tmp.message_type != SSL3_MT_CERTIFICATE_VERIFY) { 2138 S3I(s)->tmp.reuse_message = 1; 2139 if (peer != NULL) { 2140 al = SSL_AD_UNEXPECTED_MESSAGE; 2141 SSLerror(s, SSL_R_MISSING_VERIFY_MESSAGE); 2142 goto f_err; 2143 } 2144 ret = 1; 2145 goto end; 2146 } 2147 2148 if (peer == NULL) { 2149 SSLerror(s, SSL_R_NO_CLIENT_CERT_RECEIVED); 2150 al = SSL_AD_UNEXPECTED_MESSAGE; 2151 goto f_err; 2152 } 2153 2154 if (!(type & EVP_PKT_SIGN)) { 2155 SSLerror(s, SSL_R_SIGNATURE_FOR_NON_SIGNING_CERTIFICATE); 2156 al = SSL_AD_ILLEGAL_PARAMETER; 2157 goto f_err; 2158 } 2159 2160 if (S3I(s)->change_cipher_spec) { 2161 SSLerror(s, SSL_R_CCS_RECEIVED_EARLY); 2162 al = SSL_AD_UNEXPECTED_MESSAGE; 2163 goto f_err; 2164 } 2165 2166 /* 2167 * Check for broken implementations of GOST ciphersuites. 2168 * 2169 * If key is GOST and n is exactly 64, it is a bare 2170 * signature without length field. 2171 */ 2172 if ((pkey->type == NID_id_GostR3410_94 || 2173 pkey->type == NID_id_GostR3410_2001) && CBS_len(&cbs) == 64) { 2174 CBS_dup(&cbs, &signature); 2175 if (!CBS_skip(&cbs, CBS_len(&cbs))) 2176 goto err; 2177 } else { 2178 if (SSL_USE_SIGALGS(s)) { 2179 if (!CBS_get_u8(&cbs, &hash_id)) 2180 goto truncated; 2181 if (!CBS_get_u8(&cbs, &sig_id)) 2182 goto truncated; 2183 2184 if ((md = tls12_get_hash(hash_id)) == NULL) { 2185 SSLerror(s, SSL_R_UNKNOWN_DIGEST); 2186 al = SSL_AD_DECODE_ERROR; 2187 goto f_err; 2188 } 2189 2190 /* Check key type is consistent with signature. */ 2191 if ((sigalg = tls12_get_sigid(pkey)) == -1) { 2192 /* Should never happen */ 2193 SSLerror(s, ERR_R_INTERNAL_ERROR); 2194 goto err; 2195 } 2196 if (sigalg != sig_id) { 2197 SSLerror(s, SSL_R_WRONG_SIGNATURE_TYPE); 2198 al = SSL_AD_DECODE_ERROR; 2199 goto f_err; 2200 } 2201 } 2202 if (!CBS_get_u16_length_prefixed(&cbs, &signature)) 2203 goto err; 2204 } 2205 if (CBS_len(&signature) > EVP_PKEY_size(pkey)) { 2206 SSLerror(s, SSL_R_WRONG_SIGNATURE_SIZE); 2207 al = SSL_AD_DECODE_ERROR; 2208 goto f_err; 2209 } 2210 if (CBS_len(&cbs) != 0) { 2211 al = SSL_AD_DECODE_ERROR; 2212 SSLerror(s, SSL_R_EXTRA_DATA_IN_MESSAGE); 2213 goto f_err; 2214 } 2215 2216 if (SSL_USE_SIGALGS(s)) { 2217 hdatalen = BIO_get_mem_data(S3I(s)->handshake_buffer, &hdata); 2218 if (hdatalen <= 0) { 2219 SSLerror(s, ERR_R_INTERNAL_ERROR); 2220 al = SSL_AD_INTERNAL_ERROR; 2221 goto f_err; 2222 } 2223 if (!EVP_VerifyInit_ex(&mctx, md, NULL) || 2224 !EVP_VerifyUpdate(&mctx, hdata, hdatalen)) { 2225 SSLerror(s, ERR_R_EVP_LIB); 2226 al = SSL_AD_INTERNAL_ERROR; 2227 goto f_err; 2228 } 2229 if (EVP_VerifyFinal(&mctx, CBS_data(&signature), 2230 CBS_len(&signature), pkey) <= 0) { 2231 al = SSL_AD_DECRYPT_ERROR; 2232 SSLerror(s, SSL_R_BAD_SIGNATURE); 2233 goto f_err; 2234 } 2235 } else if (pkey->type == EVP_PKEY_RSA) { 2236 verify = RSA_verify(NID_md5_sha1, S3I(s)->tmp.cert_verify_md, 2237 MD5_DIGEST_LENGTH + SHA_DIGEST_LENGTH, CBS_data(&signature), 2238 CBS_len(&signature), pkey->pkey.rsa); 2239 if (verify < 0) { 2240 al = SSL_AD_DECRYPT_ERROR; 2241 SSLerror(s, SSL_R_BAD_RSA_DECRYPT); 2242 goto f_err; 2243 } 2244 if (verify == 0) { 2245 al = SSL_AD_DECRYPT_ERROR; 2246 SSLerror(s, SSL_R_BAD_RSA_SIGNATURE); 2247 goto f_err; 2248 } 2249 } else if (pkey->type == EVP_PKEY_EC) { 2250 verify = ECDSA_verify(pkey->save_type, 2251 &(S3I(s)->tmp.cert_verify_md[MD5_DIGEST_LENGTH]), 2252 SHA_DIGEST_LENGTH, CBS_data(&signature), 2253 CBS_len(&signature), pkey->pkey.ec); 2254 if (verify <= 0) { 2255 al = SSL_AD_DECRYPT_ERROR; 2256 SSLerror(s, SSL_R_BAD_ECDSA_SIGNATURE); 2257 goto f_err; 2258 } 2259 } else 2260 #ifndef OPENSSL_NO_GOST 2261 if (pkey->type == NID_id_GostR3410_94 || 2262 pkey->type == NID_id_GostR3410_2001) { 2263 unsigned char sigbuf[128]; 2264 unsigned int siglen = sizeof(sigbuf); 2265 EVP_PKEY_CTX *pctx; 2266 int nid; 2267 2268 hdatalen = BIO_get_mem_data(S3I(s)->handshake_buffer, &hdata); 2269 if (hdatalen <= 0) { 2270 SSLerror(s, ERR_R_INTERNAL_ERROR); 2271 al = SSL_AD_INTERNAL_ERROR; 2272 goto f_err; 2273 } 2274 if (!EVP_PKEY_get_default_digest_nid(pkey, &nid) || 2275 !(md = EVP_get_digestbynid(nid))) { 2276 SSLerror(s, ERR_R_EVP_LIB); 2277 al = SSL_AD_INTERNAL_ERROR; 2278 goto f_err; 2279 } 2280 if ((pctx = EVP_PKEY_CTX_new(pkey, NULL)) == NULL) { 2281 SSLerror(s, ERR_R_EVP_LIB); 2282 al = SSL_AD_INTERNAL_ERROR; 2283 goto f_err; 2284 } 2285 if (!EVP_DigestInit_ex(&mctx, md, NULL) || 2286 !EVP_DigestUpdate(&mctx, hdata, hdatalen) || 2287 !EVP_DigestFinal(&mctx, sigbuf, &siglen) || 2288 (EVP_PKEY_verify_init(pctx) <= 0) || 2289 (EVP_PKEY_CTX_set_signature_md(pctx, md) <= 0) || 2290 (EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_VERIFY, 2291 EVP_PKEY_CTRL_GOST_SIG_FORMAT, 2292 GOST_SIG_FORMAT_RS_LE, NULL) <= 0)) { 2293 SSLerror(s, ERR_R_EVP_LIB); 2294 al = SSL_AD_INTERNAL_ERROR; 2295 EVP_PKEY_CTX_free(pctx); 2296 goto f_err; 2297 } 2298 if (EVP_PKEY_verify(pctx, CBS_data(&signature), 2299 CBS_len(&signature), sigbuf, siglen) <= 0) { 2300 al = SSL_AD_DECRYPT_ERROR; 2301 SSLerror(s, SSL_R_BAD_SIGNATURE); 2302 EVP_PKEY_CTX_free(pctx); 2303 goto f_err; 2304 } 2305 2306 EVP_PKEY_CTX_free(pctx); 2307 } else 2308 #endif 2309 { 2310 SSLerror(s, ERR_R_INTERNAL_ERROR); 2311 al = SSL_AD_UNSUPPORTED_CERTIFICATE; 2312 goto f_err; 2313 } 2314 2315 ret = 1; 2316 if (0) { 2317 truncated: 2318 al = SSL_AD_DECODE_ERROR; 2319 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 2320 f_err: 2321 ssl3_send_alert(s, SSL3_AL_FATAL, al); 2322 } 2323 end: 2324 if (S3I(s)->handshake_buffer) { 2325 BIO_free(S3I(s)->handshake_buffer); 2326 S3I(s)->handshake_buffer = NULL; 2327 s->s3->flags &= ~TLS1_FLAGS_KEEP_HANDSHAKE; 2328 } 2329 err: 2330 EVP_MD_CTX_cleanup(&mctx); 2331 EVP_PKEY_free(pkey); 2332 return (ret); 2333 } 2334 2335 int 2336 ssl3_get_client_certificate(SSL *s) 2337 { 2338 CBS cbs, client_certs; 2339 int i, ok, al, ret = -1; 2340 X509 *x = NULL; 2341 long n; 2342 const unsigned char *q; 2343 STACK_OF(X509) *sk = NULL; 2344 2345 n = s->method->internal->ssl_get_message(s, SSL3_ST_SR_CERT_A, SSL3_ST_SR_CERT_B, 2346 -1, s->internal->max_cert_list, &ok); 2347 2348 if (!ok) 2349 return ((int)n); 2350 2351 if (S3I(s)->tmp.message_type == SSL3_MT_CLIENT_KEY_EXCHANGE) { 2352 if ((s->verify_mode & SSL_VERIFY_PEER) && 2353 (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { 2354 SSLerror(s, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); 2355 al = SSL_AD_HANDSHAKE_FAILURE; 2356 goto f_err; 2357 } 2358 /* 2359 * If tls asked for a client cert, 2360 * the client must return a 0 list. 2361 */ 2362 if (S3I(s)->tmp.cert_request) { 2363 SSLerror(s, SSL_R_TLS_PEER_DID_NOT_RESPOND_WITH_CERTIFICATE_LIST 2364 ); 2365 al = SSL_AD_UNEXPECTED_MESSAGE; 2366 goto f_err; 2367 } 2368 S3I(s)->tmp.reuse_message = 1; 2369 return (1); 2370 } 2371 2372 if (S3I(s)->tmp.message_type != SSL3_MT_CERTIFICATE) { 2373 al = SSL_AD_UNEXPECTED_MESSAGE; 2374 SSLerror(s, SSL_R_WRONG_MESSAGE_TYPE); 2375 goto f_err; 2376 } 2377 2378 if (n < 0) 2379 goto truncated; 2380 2381 CBS_init(&cbs, s->internal->init_msg, n); 2382 2383 if ((sk = sk_X509_new_null()) == NULL) { 2384 SSLerror(s, ERR_R_MALLOC_FAILURE); 2385 goto err; 2386 } 2387 2388 if (!CBS_get_u24_length_prefixed(&cbs, &client_certs) || 2389 CBS_len(&cbs) != 0) 2390 goto truncated; 2391 2392 while (CBS_len(&client_certs) > 0) { 2393 CBS cert; 2394 2395 if (!CBS_get_u24_length_prefixed(&client_certs, &cert)) { 2396 al = SSL_AD_DECODE_ERROR; 2397 SSLerror(s, SSL_R_CERT_LENGTH_MISMATCH); 2398 goto f_err; 2399 } 2400 2401 q = CBS_data(&cert); 2402 x = d2i_X509(NULL, &q, CBS_len(&cert)); 2403 if (x == NULL) { 2404 SSLerror(s, ERR_R_ASN1_LIB); 2405 goto err; 2406 } 2407 if (q != CBS_data(&cert) + CBS_len(&cert)) { 2408 al = SSL_AD_DECODE_ERROR; 2409 SSLerror(s, SSL_R_CERT_LENGTH_MISMATCH); 2410 goto f_err; 2411 } 2412 if (!sk_X509_push(sk, x)) { 2413 SSLerror(s, ERR_R_MALLOC_FAILURE); 2414 goto err; 2415 } 2416 x = NULL; 2417 } 2418 2419 if (sk_X509_num(sk) <= 0) { 2420 /* 2421 * TLS does not mind 0 certs returned. 2422 * Fail for TLS only if we required a certificate. 2423 */ 2424 if ((s->verify_mode & SSL_VERIFY_PEER) && 2425 (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { 2426 SSLerror(s, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); 2427 al = SSL_AD_HANDSHAKE_FAILURE; 2428 goto f_err; 2429 } 2430 /* No client certificate so digest cached records */ 2431 if (S3I(s)->handshake_buffer && !tls1_digest_cached_records(s)) { 2432 al = SSL_AD_INTERNAL_ERROR; 2433 goto f_err; 2434 } 2435 } else { 2436 i = ssl_verify_cert_chain(s, sk); 2437 if (i <= 0) { 2438 al = ssl_verify_alarm_type(s->verify_result); 2439 SSLerror(s, SSL_R_NO_CERTIFICATE_RETURNED); 2440 goto f_err; 2441 } 2442 } 2443 2444 X509_free(s->session->peer); 2445 s->session->peer = sk_X509_shift(sk); 2446 s->session->verify_result = s->verify_result; 2447 2448 /* 2449 * With the current implementation, sess_cert will always be NULL 2450 * when we arrive here 2451 */ 2452 if (SSI(s)->sess_cert == NULL) { 2453 SSI(s)->sess_cert = ssl_sess_cert_new(); 2454 if (SSI(s)->sess_cert == NULL) { 2455 SSLerror(s, ERR_R_MALLOC_FAILURE); 2456 goto err; 2457 } 2458 } 2459 sk_X509_pop_free(SSI(s)->sess_cert->cert_chain, X509_free); 2460 SSI(s)->sess_cert->cert_chain = sk; 2461 2462 /* 2463 * Inconsistency alert: cert_chain does *not* include the 2464 * peer's own certificate, while we do include it in s3_clnt.c 2465 */ 2466 2467 sk = NULL; 2468 2469 ret = 1; 2470 if (0) { 2471 truncated: 2472 al = SSL_AD_DECODE_ERROR; 2473 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 2474 f_err: 2475 ssl3_send_alert(s, SSL3_AL_FATAL, al); 2476 } 2477 err: 2478 X509_free(x); 2479 sk_X509_pop_free(sk, X509_free); 2480 2481 return (ret); 2482 } 2483 2484 int 2485 ssl3_send_server_certificate(SSL *s) 2486 { 2487 CBB cbb, server_cert; 2488 X509 *x; 2489 2490 /* 2491 * Server Certificate - RFC 5246, section 7.4.2. 2492 */ 2493 2494 memset(&cbb, 0, sizeof(cbb)); 2495 2496 if (S3I(s)->hs.state == SSL3_ST_SW_CERT_A) { 2497 if ((x = ssl_get_server_send_cert(s)) == NULL) { 2498 SSLerror(s, ERR_R_INTERNAL_ERROR); 2499 return (0); 2500 } 2501 2502 if (!ssl3_handshake_msg_start(s, &cbb, &server_cert, 2503 SSL3_MT_CERTIFICATE)) 2504 goto err; 2505 if (!ssl3_output_cert_chain(s, &server_cert, x)) 2506 goto err; 2507 if (!ssl3_handshake_msg_finish(s, &cbb)) 2508 goto err; 2509 2510 S3I(s)->hs.state = SSL3_ST_SW_CERT_B; 2511 } 2512 2513 /* SSL3_ST_SW_CERT_B */ 2514 return (ssl3_handshake_write(s)); 2515 2516 err: 2517 CBB_cleanup(&cbb); 2518 2519 return (0); 2520 } 2521 2522 /* send a new session ticket (not necessarily for a new session) */ 2523 int 2524 ssl3_send_newsession_ticket(SSL *s) 2525 { 2526 CBB cbb, session_ticket, ticket; 2527 SSL_CTX *tctx = s->initial_ctx; 2528 size_t enc_session_len, enc_session_max_len, hmac_len; 2529 size_t session_len = 0; 2530 unsigned char *enc_session = NULL, *session = NULL; 2531 unsigned char iv[EVP_MAX_IV_LENGTH]; 2532 unsigned char key_name[16]; 2533 unsigned char *hmac; 2534 unsigned int hlen; 2535 EVP_CIPHER_CTX ctx; 2536 HMAC_CTX hctx; 2537 int len; 2538 2539 /* 2540 * New Session Ticket - RFC 5077, section 3.3. 2541 */ 2542 2543 EVP_CIPHER_CTX_init(&ctx); 2544 HMAC_CTX_init(&hctx); 2545 2546 memset(&cbb, 0, sizeof(cbb)); 2547 2548 if (S3I(s)->hs.state == SSL3_ST_SW_SESSION_TICKET_A) { 2549 if (!ssl3_handshake_msg_start(s, &cbb, &session_ticket, 2550 SSL3_MT_NEWSESSION_TICKET)) 2551 goto err; 2552 2553 if (!SSL_SESSION_ticket(s->session, &session, &session_len)) 2554 goto err; 2555 if (session_len > 0xffff) 2556 goto err; 2557 2558 /* 2559 * Initialize HMAC and cipher contexts. If callback is present 2560 * it does all the work, otherwise use generated values from 2561 * parent context. 2562 */ 2563 if (tctx->internal->tlsext_ticket_key_cb != NULL) { 2564 if (tctx->internal->tlsext_ticket_key_cb(s, 2565 key_name, iv, &ctx, &hctx, 1) < 0) { 2566 EVP_CIPHER_CTX_cleanup(&ctx); 2567 goto err; 2568 } 2569 } else { 2570 arc4random_buf(iv, 16); 2571 EVP_EncryptInit_ex(&ctx, EVP_aes_128_cbc(), NULL, 2572 tctx->internal->tlsext_tick_aes_key, iv); 2573 HMAC_Init_ex(&hctx, tctx->internal->tlsext_tick_hmac_key, 2574 16, tlsext_tick_md(), NULL); 2575 memcpy(key_name, tctx->internal->tlsext_tick_key_name, 16); 2576 } 2577 2578 /* Encrypt the session state. */ 2579 enc_session_max_len = session_len + EVP_MAX_BLOCK_LENGTH; 2580 if ((enc_session = calloc(1, enc_session_max_len)) == NULL) 2581 goto err; 2582 enc_session_len = 0; 2583 if (!EVP_EncryptUpdate(&ctx, enc_session, &len, session, 2584 session_len)) 2585 goto err; 2586 enc_session_len += len; 2587 if (!EVP_EncryptFinal_ex(&ctx, enc_session + enc_session_len, 2588 &len)) 2589 goto err; 2590 enc_session_len += len; 2591 2592 if (enc_session_len > enc_session_max_len) 2593 goto err; 2594 2595 /* Generate the HMAC. */ 2596 if (!HMAC_Update(&hctx, key_name, sizeof(key_name))) 2597 goto err; 2598 if (!HMAC_Update(&hctx, iv, EVP_CIPHER_CTX_iv_length(&ctx))) 2599 goto err; 2600 if (!HMAC_Update(&hctx, enc_session, enc_session_len)) 2601 goto err; 2602 2603 if ((hmac_len = HMAC_size(&hctx)) <= 0) 2604 goto err; 2605 2606 /* 2607 * Ticket lifetime hint (advisory only): 2608 * We leave this unspecified for resumed session 2609 * (for simplicity), and guess that tickets for new 2610 * sessions will live as long as their sessions. 2611 */ 2612 if (!CBB_add_u32(&session_ticket, 2613 s->internal->hit ? 0 : s->session->timeout)) 2614 goto err; 2615 2616 if (!CBB_add_u16_length_prefixed(&session_ticket, &ticket)) 2617 goto err; 2618 if (!CBB_add_bytes(&ticket, key_name, sizeof(key_name))) 2619 goto err; 2620 if (!CBB_add_bytes(&ticket, iv, EVP_CIPHER_CTX_iv_length(&ctx))) 2621 goto err; 2622 if (!CBB_add_bytes(&ticket, enc_session, enc_session_len)) 2623 goto err; 2624 if (!CBB_add_space(&ticket, &hmac, hmac_len)) 2625 goto err; 2626 2627 if (!HMAC_Final(&hctx, hmac, &hlen)) 2628 goto err; 2629 if (hlen != hmac_len) 2630 goto err; 2631 2632 if (!ssl3_handshake_msg_finish(s, &cbb)) 2633 goto err; 2634 2635 S3I(s)->hs.state = SSL3_ST_SW_SESSION_TICKET_B; 2636 } 2637 2638 EVP_CIPHER_CTX_cleanup(&ctx); 2639 HMAC_CTX_cleanup(&hctx); 2640 freezero(session, session_len); 2641 free(enc_session); 2642 2643 /* SSL3_ST_SW_SESSION_TICKET_B */ 2644 return (ssl3_handshake_write(s)); 2645 2646 err: 2647 CBB_cleanup(&cbb); 2648 EVP_CIPHER_CTX_cleanup(&ctx); 2649 HMAC_CTX_cleanup(&hctx); 2650 freezero(session, session_len); 2651 free(enc_session); 2652 2653 return (-1); 2654 } 2655 2656 int 2657 ssl3_send_cert_status(SSL *s) 2658 { 2659 CBB cbb, certstatus, ocspresp; 2660 2661 memset(&cbb, 0, sizeof(cbb)); 2662 2663 if (S3I(s)->hs.state == SSL3_ST_SW_CERT_STATUS_A) { 2664 if (!ssl3_handshake_msg_start(s, &cbb, &certstatus, 2665 SSL3_MT_CERTIFICATE_STATUS)) 2666 goto err; 2667 if (!CBB_add_u8(&certstatus, s->tlsext_status_type)) 2668 goto err; 2669 if (!CBB_add_u24_length_prefixed(&certstatus, &ocspresp)) 2670 goto err; 2671 if (!CBB_add_bytes(&ocspresp, s->internal->tlsext_ocsp_resp, 2672 s->internal->tlsext_ocsp_resplen)) 2673 goto err; 2674 if (!ssl3_handshake_msg_finish(s, &cbb)) 2675 goto err; 2676 2677 S3I(s)->hs.state = SSL3_ST_SW_CERT_STATUS_B; 2678 } 2679 2680 /* SSL3_ST_SW_CERT_STATUS_B */ 2681 return (ssl3_handshake_write(s)); 2682 2683 err: 2684 CBB_cleanup(&cbb); 2685 2686 return (-1); 2687 } 2688