1 /* $OpenBSD: ssl_srvr.c,v 1.17 2017/05/07 04:22:24 beck 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" 169 170 int 171 ssl3_accept(SSL *s) 172 { 173 unsigned long alg_k; 174 void (*cb)(const SSL *ssl, int type, int val) = NULL; 175 int ret = -1; 176 int new_state, state, skip = 0; 177 178 ERR_clear_error(); 179 errno = 0; 180 181 if (s->internal->info_callback != NULL) 182 cb = s->internal->info_callback; 183 else if (s->ctx->internal->info_callback != NULL) 184 cb = s->ctx->internal->info_callback; 185 186 /* init things to blank */ 187 s->internal->in_handshake++; 188 if (!SSL_in_init(s) || SSL_in_before(s)) 189 SSL_clear(s); 190 191 if (s->cert == NULL) { 192 SSLerror(s, SSL_R_NO_CERTIFICATE_SET); 193 ret = -1; 194 goto end; 195 } 196 197 for (;;) { 198 state = S3I(s)->hs.state; 199 200 switch (S3I(s)->hs.state) { 201 case SSL_ST_RENEGOTIATE: 202 s->internal->renegotiate = 1; 203 /* S3I(s)->hs.state=SSL_ST_ACCEPT; */ 204 205 case SSL_ST_BEFORE: 206 case SSL_ST_ACCEPT: 207 case SSL_ST_BEFORE|SSL_ST_ACCEPT: 208 case SSL_ST_OK|SSL_ST_ACCEPT: 209 210 s->server = 1; 211 if (cb != NULL) 212 cb(s, SSL_CB_HANDSHAKE_START, 1); 213 214 if ((s->version >> 8) != 3) { 215 SSLerror(s, ERR_R_INTERNAL_ERROR); 216 ret = -1; 217 goto end; 218 } 219 s->internal->type = SSL_ST_ACCEPT; 220 221 if (!ssl3_setup_init_buffer(s)) { 222 ret = -1; 223 goto end; 224 } 225 if (!ssl3_setup_buffers(s)) { 226 ret = -1; 227 goto end; 228 } 229 230 s->internal->init_num = 0; 231 232 if (S3I(s)->hs.state != SSL_ST_RENEGOTIATE) { 233 /* 234 * Ok, we now need to push on a buffering BIO 235 * so that the output is sent in a way that 236 * TCP likes :-) 237 */ 238 if (!ssl_init_wbio_buffer(s, 1)) { 239 ret = -1; 240 goto end; 241 } 242 243 if (!tls1_init_finished_mac(s)) { 244 ret = -1; 245 goto end; 246 } 247 248 S3I(s)->hs.state = SSL3_ST_SR_CLNT_HELLO_A; 249 s->ctx->internal->stats.sess_accept++; 250 } else if (!S3I(s)->send_connection_binding) { 251 /* 252 * Server attempting to renegotiate with 253 * client that doesn't support secure 254 * renegotiation. 255 */ 256 SSLerror(s, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED); 257 ssl3_send_alert(s, SSL3_AL_FATAL, 258 SSL_AD_HANDSHAKE_FAILURE); 259 ret = -1; 260 goto end; 261 } else { 262 /* 263 * S3I(s)->hs.state == SSL_ST_RENEGOTIATE, 264 * we will just send a HelloRequest 265 */ 266 s->ctx->internal->stats.sess_accept_renegotiate++; 267 S3I(s)->hs.state = SSL3_ST_SW_HELLO_REQ_A; 268 } 269 break; 270 271 case SSL3_ST_SW_HELLO_REQ_A: 272 case SSL3_ST_SW_HELLO_REQ_B: 273 274 s->internal->shutdown = 0; 275 ret = ssl3_send_hello_request(s); 276 if (ret <= 0) 277 goto end; 278 S3I(s)->hs.next_state = SSL3_ST_SW_HELLO_REQ_C; 279 S3I(s)->hs.state = SSL3_ST_SW_FLUSH; 280 s->internal->init_num = 0; 281 282 if (!tls1_init_finished_mac(s)) { 283 ret = -1; 284 goto end; 285 } 286 break; 287 288 case SSL3_ST_SW_HELLO_REQ_C: 289 S3I(s)->hs.state = SSL_ST_OK; 290 break; 291 292 case SSL3_ST_SR_CLNT_HELLO_A: 293 case SSL3_ST_SR_CLNT_HELLO_B: 294 case SSL3_ST_SR_CLNT_HELLO_C: 295 296 s->internal->shutdown = 0; 297 if (s->internal->rwstate != SSL_X509_LOOKUP) { 298 ret = ssl3_get_client_hello(s); 299 if (ret <= 0) 300 goto end; 301 } 302 303 s->internal->renegotiate = 2; 304 S3I(s)->hs.state = SSL3_ST_SW_SRVR_HELLO_A; 305 s->internal->init_num = 0; 306 break; 307 308 case SSL3_ST_SW_SRVR_HELLO_A: 309 case SSL3_ST_SW_SRVR_HELLO_B: 310 ret = ssl3_send_server_hello(s); 311 if (ret <= 0) 312 goto end; 313 if (s->internal->hit) { 314 if (s->internal->tlsext_ticket_expected) 315 S3I(s)->hs.state = SSL3_ST_SW_SESSION_TICKET_A; 316 else 317 S3I(s)->hs.state = SSL3_ST_SW_CHANGE_A; 318 } 319 else 320 S3I(s)->hs.state = SSL3_ST_SW_CERT_A; 321 s->internal->init_num = 0; 322 break; 323 324 case SSL3_ST_SW_CERT_A: 325 case SSL3_ST_SW_CERT_B: 326 /* Check if it is anon DH or anon ECDH. */ 327 if (!(S3I(s)->hs.new_cipher->algorithm_auth & 328 SSL_aNULL)) { 329 ret = ssl3_send_server_certificate(s); 330 if (ret <= 0) 331 goto end; 332 if (s->internal->tlsext_status_expected) 333 S3I(s)->hs.state = SSL3_ST_SW_CERT_STATUS_A; 334 else 335 S3I(s)->hs.state = SSL3_ST_SW_KEY_EXCH_A; 336 } else { 337 skip = 1; 338 S3I(s)->hs.state = SSL3_ST_SW_KEY_EXCH_A; 339 } 340 s->internal->init_num = 0; 341 break; 342 343 case SSL3_ST_SW_KEY_EXCH_A: 344 case SSL3_ST_SW_KEY_EXCH_B: 345 alg_k = S3I(s)->hs.new_cipher->algorithm_mkey; 346 347 /* 348 * Only send if using a DH key exchange. 349 * 350 * For ECC ciphersuites, we send a ServerKeyExchange 351 * message only if the cipher suite is ECDHE. In other 352 * cases, the server certificate contains the server's 353 * public key for key exchange. 354 */ 355 if (alg_k & (SSL_kDHE|SSL_kECDHE)) { 356 ret = ssl3_send_server_key_exchange(s); 357 if (ret <= 0) 358 goto end; 359 } else 360 skip = 1; 361 362 S3I(s)->hs.state = SSL3_ST_SW_CERT_REQ_A; 363 s->internal->init_num = 0; 364 break; 365 366 case SSL3_ST_SW_CERT_REQ_A: 367 case SSL3_ST_SW_CERT_REQ_B: 368 /* 369 * Determine whether or not we need to request a 370 * certificate. 371 * 372 * Do not request a certificate if: 373 * 374 * - We did not ask for it (SSL_VERIFY_PEER is unset). 375 * 376 * - SSL_VERIFY_CLIENT_ONCE is set and we are 377 * renegotiating. 378 * 379 * - We are using an anonymous ciphersuites 380 * (see section "Certificate request" in SSL 3 drafts 381 * and in RFC 2246) ... except when the application 382 * insists on verification (against the specs, but 383 * s3_clnt.c accepts this for SSL 3). 384 */ 385 if (!(s->verify_mode & SSL_VERIFY_PEER) || 386 ((s->session->peer != NULL) && 387 (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) || 388 ((S3I(s)->hs.new_cipher->algorithm_auth & 389 SSL_aNULL) && !(s->verify_mode & 390 SSL_VERIFY_FAIL_IF_NO_PEER_CERT))) { 391 /* No cert request */ 392 skip = 1; 393 S3I(s)->tmp.cert_request = 0; 394 S3I(s)->hs.state = SSL3_ST_SW_SRVR_DONE_A; 395 if (S3I(s)->handshake_buffer) { 396 if (!tls1_digest_cached_records(s)) { 397 ret = -1; 398 goto end; 399 } 400 } 401 } else { 402 S3I(s)->tmp.cert_request = 1; 403 ret = ssl3_send_certificate_request(s); 404 if (ret <= 0) 405 goto end; 406 S3I(s)->hs.state = SSL3_ST_SW_SRVR_DONE_A; 407 s->internal->init_num = 0; 408 } 409 break; 410 411 case SSL3_ST_SW_SRVR_DONE_A: 412 case SSL3_ST_SW_SRVR_DONE_B: 413 ret = ssl3_send_server_done(s); 414 if (ret <= 0) 415 goto end; 416 S3I(s)->hs.next_state = SSL3_ST_SR_CERT_A; 417 S3I(s)->hs.state = SSL3_ST_SW_FLUSH; 418 s->internal->init_num = 0; 419 break; 420 421 case SSL3_ST_SW_FLUSH: 422 423 /* 424 * This code originally checked to see if 425 * any data was pending using BIO_CTRL_INFO 426 * and then flushed. This caused problems 427 * as documented in PR#1939. The proposed 428 * fix doesn't completely resolve this issue 429 * as buggy implementations of BIO_CTRL_PENDING 430 * still exist. So instead we just flush 431 * unconditionally. 432 */ 433 434 s->internal->rwstate = SSL_WRITING; 435 if (BIO_flush(s->wbio) <= 0) { 436 ret = -1; 437 goto end; 438 } 439 s->internal->rwstate = SSL_NOTHING; 440 441 S3I(s)->hs.state = S3I(s)->hs.next_state; 442 break; 443 444 case SSL3_ST_SR_CERT_A: 445 case SSL3_ST_SR_CERT_B: 446 if (S3I(s)->tmp.cert_request) { 447 ret = ssl3_get_client_certificate(s); 448 if (ret <= 0) 449 goto end; 450 } 451 s->internal->init_num = 0; 452 S3I(s)->hs.state = SSL3_ST_SR_KEY_EXCH_A; 453 break; 454 455 case SSL3_ST_SR_KEY_EXCH_A: 456 case SSL3_ST_SR_KEY_EXCH_B: 457 ret = ssl3_get_client_key_exchange(s); 458 if (ret <= 0) 459 goto end; 460 alg_k = S3I(s)->hs.new_cipher->algorithm_mkey; 461 if (ret == 2) { 462 /* 463 * For the ECDH ciphersuites when 464 * the client sends its ECDH pub key in 465 * a certificate, the CertificateVerify 466 * message is not sent. 467 * Also for GOST ciphersuites when 468 * the client uses its key from the certificate 469 * for key exchange. 470 */ 471 if (S3I(s)->next_proto_neg_seen) 472 S3I(s)->hs.state = SSL3_ST_SR_NEXT_PROTO_A; 473 else 474 S3I(s)->hs.state = SSL3_ST_SR_FINISHED_A; 475 s->internal->init_num = 0; 476 } else if (SSL_USE_SIGALGS(s) || (alg_k & SSL_kGOST)) { 477 S3I(s)->hs.state = SSL3_ST_SR_CERT_VRFY_A; 478 s->internal->init_num = 0; 479 if (!s->session->peer) 480 break; 481 /* 482 * For sigalgs freeze the handshake buffer 483 * at this point and digest cached records. 484 */ 485 if (!S3I(s)->handshake_buffer) { 486 SSLerror(s, ERR_R_INTERNAL_ERROR); 487 ret = -1; 488 goto end; 489 } 490 s->s3->flags |= TLS1_FLAGS_KEEP_HANDSHAKE; 491 if (!tls1_digest_cached_records(s)) { 492 ret = -1; 493 goto end; 494 } 495 } else { 496 S3I(s)->hs.state = SSL3_ST_SR_CERT_VRFY_A; 497 s->internal->init_num = 0; 498 499 /* 500 * We need to get hashes here so if there is 501 * a client cert, it can be verified. 502 */ 503 if (S3I(s)->handshake_buffer) { 504 if (!tls1_digest_cached_records(s)) { 505 ret = -1; 506 goto end; 507 } 508 } 509 if (!tls1_handshake_hash_value(s, 510 S3I(s)->tmp.cert_verify_md, 511 sizeof(S3I(s)->tmp.cert_verify_md), 512 NULL)) { 513 ret = -1; 514 goto end; 515 } 516 } 517 break; 518 519 case SSL3_ST_SR_CERT_VRFY_A: 520 case SSL3_ST_SR_CERT_VRFY_B: 521 s->s3->flags |= SSL3_FLAGS_CCS_OK; 522 523 /* we should decide if we expected this one */ 524 ret = ssl3_get_cert_verify(s); 525 if (ret <= 0) 526 goto end; 527 528 if (S3I(s)->next_proto_neg_seen) 529 S3I(s)->hs.state = SSL3_ST_SR_NEXT_PROTO_A; 530 else 531 S3I(s)->hs.state = SSL3_ST_SR_FINISHED_A; 532 s->internal->init_num = 0; 533 break; 534 535 case SSL3_ST_SR_NEXT_PROTO_A: 536 case SSL3_ST_SR_NEXT_PROTO_B: 537 ret = ssl3_get_next_proto(s); 538 if (ret <= 0) 539 goto end; 540 s->internal->init_num = 0; 541 S3I(s)->hs.state = SSL3_ST_SR_FINISHED_A; 542 break; 543 544 case SSL3_ST_SR_FINISHED_A: 545 case SSL3_ST_SR_FINISHED_B: 546 s->s3->flags |= SSL3_FLAGS_CCS_OK; 547 ret = ssl3_get_finished(s, SSL3_ST_SR_FINISHED_A, 548 SSL3_ST_SR_FINISHED_B); 549 if (ret <= 0) 550 goto end; 551 if (s->internal->hit) 552 S3I(s)->hs.state = SSL_ST_OK; 553 else if (s->internal->tlsext_ticket_expected) 554 S3I(s)->hs.state = SSL3_ST_SW_SESSION_TICKET_A; 555 else 556 S3I(s)->hs.state = SSL3_ST_SW_CHANGE_A; 557 s->internal->init_num = 0; 558 break; 559 560 case SSL3_ST_SW_SESSION_TICKET_A: 561 case SSL3_ST_SW_SESSION_TICKET_B: 562 ret = ssl3_send_newsession_ticket(s); 563 if (ret <= 0) 564 goto end; 565 S3I(s)->hs.state = SSL3_ST_SW_CHANGE_A; 566 s->internal->init_num = 0; 567 break; 568 569 case SSL3_ST_SW_CERT_STATUS_A: 570 case SSL3_ST_SW_CERT_STATUS_B: 571 ret = ssl3_send_cert_status(s); 572 if (ret <= 0) 573 goto end; 574 S3I(s)->hs.state = SSL3_ST_SW_KEY_EXCH_A; 575 s->internal->init_num = 0; 576 break; 577 578 579 case SSL3_ST_SW_CHANGE_A: 580 case SSL3_ST_SW_CHANGE_B: 581 582 s->session->cipher = S3I(s)->hs.new_cipher; 583 if (!tls1_setup_key_block(s)) { 584 ret = -1; 585 goto end; 586 } 587 588 ret = ssl3_send_change_cipher_spec(s, 589 SSL3_ST_SW_CHANGE_A, SSL3_ST_SW_CHANGE_B); 590 591 if (ret <= 0) 592 goto end; 593 S3I(s)->hs.state = SSL3_ST_SW_FINISHED_A; 594 s->internal->init_num = 0; 595 596 if (!tls1_change_cipher_state( 597 s, SSL3_CHANGE_CIPHER_SERVER_WRITE)) { 598 ret = -1; 599 goto end; 600 } 601 602 break; 603 604 case SSL3_ST_SW_FINISHED_A: 605 case SSL3_ST_SW_FINISHED_B: 606 ret = ssl3_send_finished(s, 607 SSL3_ST_SW_FINISHED_A, SSL3_ST_SW_FINISHED_B, 608 TLS_MD_SERVER_FINISH_CONST, 609 TLS_MD_SERVER_FINISH_CONST_SIZE); 610 if (ret <= 0) 611 goto end; 612 S3I(s)->hs.state = SSL3_ST_SW_FLUSH; 613 if (s->internal->hit) { 614 if (S3I(s)->next_proto_neg_seen) { 615 s->s3->flags |= SSL3_FLAGS_CCS_OK; 616 S3I(s)->hs.next_state = 617 SSL3_ST_SR_NEXT_PROTO_A; 618 } else 619 S3I(s)->hs.next_state = 620 SSL3_ST_SR_FINISHED_A; 621 } else 622 S3I(s)->hs.next_state = SSL_ST_OK; 623 s->internal->init_num = 0; 624 break; 625 626 case SSL_ST_OK: 627 /* clean a few things up */ 628 tls1_cleanup_key_block(s); 629 630 BUF_MEM_free(s->internal->init_buf); 631 s->internal->init_buf = NULL; 632 633 /* remove buffering on output */ 634 ssl_free_wbio_buffer(s); 635 636 s->internal->init_num = 0; 637 638 /* skipped if we just sent a HelloRequest */ 639 if (s->internal->renegotiate == 2) { 640 s->internal->renegotiate = 0; 641 s->internal->new_session = 0; 642 643 ssl_update_cache(s, SSL_SESS_CACHE_SERVER); 644 645 s->ctx->internal->stats.sess_accept_good++; 646 /* s->server=1; */ 647 s->internal->handshake_func = ssl3_accept; 648 649 if (cb != NULL) 650 cb(s, SSL_CB_HANDSHAKE_DONE, 1); 651 } 652 653 ret = 1; 654 goto end; 655 /* break; */ 656 657 default: 658 SSLerror(s, SSL_R_UNKNOWN_STATE); 659 ret = -1; 660 goto end; 661 /* break; */ 662 } 663 664 if (!S3I(s)->tmp.reuse_message && !skip) { 665 if (s->internal->debug) { 666 if ((ret = BIO_flush(s->wbio)) <= 0) 667 goto end; 668 } 669 670 671 if ((cb != NULL) && (S3I(s)->hs.state != state)) { 672 new_state = S3I(s)->hs.state; 673 S3I(s)->hs.state = state; 674 cb(s, SSL_CB_ACCEPT_LOOP, 1); 675 S3I(s)->hs.state = new_state; 676 } 677 } 678 skip = 0; 679 } 680 end: 681 /* BIO_flush(s->wbio); */ 682 683 s->internal->in_handshake--; 684 if (cb != NULL) 685 cb(s, SSL_CB_ACCEPT_EXIT, ret); 686 return (ret); 687 } 688 689 int 690 ssl3_send_hello_request(SSL *s) 691 { 692 CBB cbb, hello; 693 694 memset(&cbb, 0, sizeof(cbb)); 695 696 if (S3I(s)->hs.state == SSL3_ST_SW_HELLO_REQ_A) { 697 if (!ssl3_handshake_msg_start_cbb(s, &cbb, &hello, 698 SSL3_MT_HELLO_REQUEST)) 699 goto err; 700 if (!ssl3_handshake_msg_finish_cbb(s, &cbb)) 701 goto err; 702 703 S3I(s)->hs.state = SSL3_ST_SW_HELLO_REQ_B; 704 } 705 706 /* SSL3_ST_SW_HELLO_REQ_B */ 707 return (ssl3_handshake_write(s)); 708 709 err: 710 CBB_cleanup(&cbb); 711 712 return (-1); 713 } 714 715 int 716 ssl3_get_client_hello(SSL *s) 717 { 718 CBS cbs, client_random, session_id, cookie, cipher_suites; 719 CBS compression_methods; 720 uint16_t client_version; 721 uint8_t comp_method; 722 int comp_null; 723 int i, j, ok, al, ret = -1, cookie_valid = 0; 724 long n; 725 unsigned long id; 726 unsigned char *p, *d; 727 SSL_CIPHER *c; 728 STACK_OF(SSL_CIPHER) *ciphers = NULL; 729 unsigned long alg_k; 730 const SSL_METHOD *method; 731 uint16_t shared_version; 732 unsigned char *end; 733 734 /* 735 * We do this so that we will respond with our native type. 736 * If we are TLSv1 and we get SSLv3, we will respond with TLSv1, 737 * This down switching should be handled by a different method. 738 * If we are SSLv3, we will respond with SSLv3, even if prompted with 739 * TLSv1. 740 */ 741 if (S3I(s)->hs.state == SSL3_ST_SR_CLNT_HELLO_A) { 742 S3I(s)->hs.state = SSL3_ST_SR_CLNT_HELLO_B; 743 } 744 745 s->internal->first_packet = 1; 746 n = s->method->internal->ssl_get_message(s, SSL3_ST_SR_CLNT_HELLO_B, 747 SSL3_ST_SR_CLNT_HELLO_C, SSL3_MT_CLIENT_HELLO, 748 SSL3_RT_MAX_PLAIN_LENGTH, &ok); 749 if (!ok) 750 return ((int)n); 751 s->internal->first_packet = 0; 752 753 if (n < 0) 754 goto err; 755 756 d = p = (unsigned char *)s->internal->init_msg; 757 end = d + n; 758 759 CBS_init(&cbs, s->internal->init_msg, n); 760 761 /* 762 * Use version from inside client hello, not from record header. 763 * (may differ: see RFC 2246, Appendix E, second paragraph) 764 */ 765 if (!CBS_get_u16(&cbs, &client_version)) 766 goto truncated; 767 768 if (ssl_max_shared_version(s, client_version, &shared_version) != 1) { 769 SSLerror(s, SSL_R_WRONG_VERSION_NUMBER); 770 if ((s->client_version >> 8) == SSL3_VERSION_MAJOR && 771 !s->internal->enc_write_ctx && !s->internal->write_hash) { 772 /* 773 * Similar to ssl3_get_record, send alert using remote 774 * version number. 775 */ 776 s->version = s->client_version; 777 } 778 al = SSL_AD_PROTOCOL_VERSION; 779 goto f_err; 780 } 781 s->client_version = client_version; 782 s->version = shared_version; 783 784 if ((method = tls1_get_server_method(shared_version)) == NULL) 785 method = dtls1_get_server_method(shared_version); 786 if (method == NULL) { 787 SSLerror(s, ERR_R_INTERNAL_ERROR); 788 goto err; 789 } 790 s->method = method; 791 792 if (!CBS_get_bytes(&cbs, &client_random, SSL3_RANDOM_SIZE)) 793 goto truncated; 794 if (!CBS_get_u8_length_prefixed(&cbs, &session_id)) 795 goto truncated; 796 797 /* 798 * If we require cookies (DTLS) and this ClientHello doesn't 799 * contain one, just return since we do not want to 800 * allocate any memory yet. So check cookie length... 801 */ 802 if (SSL_IS_DTLS(s)) { 803 if (!CBS_get_u8_length_prefixed(&cbs, &cookie)) 804 goto truncated; 805 if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) { 806 if (CBS_len(&cookie) == 0) 807 return (1); 808 } 809 } 810 811 if (!CBS_write_bytes(&client_random, s->s3->client_random, 812 sizeof(s->s3->client_random), NULL)) 813 goto err; 814 815 s->internal->hit = 0; 816 817 /* 818 * Versions before 0.9.7 always allow clients to resume sessions in 819 * renegotiation. 0.9.7 and later allow this by default, but optionally 820 * ignore resumption requests with flag 821 * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION (it's a new flag 822 * rather than a change to default behavior so that applications 823 * relying on this for security won't even compile against older 824 * library versions). 825 * 826 * 1.0.1 and later also have a function SSL_renegotiate_abbreviated() 827 * to request renegotiation but not a new session (s->internal->new_session 828 * remains unset): for servers, this essentially just means that the 829 * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION setting will be 830 * ignored. 831 */ 832 if ((s->internal->new_session && (s->internal->options & 833 SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION))) { 834 if (!ssl_get_new_session(s, 1)) 835 goto err; 836 } else { 837 /* XXX - pass CBS through instead... */ 838 i = ssl_get_prev_session(s, 839 (unsigned char *)CBS_data(&session_id), 840 CBS_len(&session_id), end); 841 if (i == 1) { /* previous session */ 842 s->internal->hit = 1; 843 } else if (i == -1) 844 goto err; 845 else { 846 /* i == 0 */ 847 if (!ssl_get_new_session(s, 1)) 848 goto err; 849 } 850 } 851 852 if (SSL_IS_DTLS(s)) { 853 /* 854 * The ClientHello may contain a cookie even if the HelloVerify 855 * message has not been sent - make sure that it does not cause 856 * an overflow. 857 */ 858 if (CBS_len(&cookie) > sizeof(D1I(s)->rcvd_cookie)) { 859 al = SSL_AD_DECODE_ERROR; 860 SSLerror(s, SSL_R_COOKIE_MISMATCH); 861 goto f_err; 862 } 863 864 /* Verify the cookie if appropriate option is set. */ 865 if ((SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) && 866 CBS_len(&cookie) > 0) { 867 size_t cookie_len; 868 869 /* XXX - rcvd_cookie seems to only be used here... */ 870 if (!CBS_write_bytes(&cookie, D1I(s)->rcvd_cookie, 871 sizeof(D1I(s)->rcvd_cookie), &cookie_len)) 872 goto err; 873 874 if (s->ctx->internal->app_verify_cookie_cb != NULL) { 875 if (s->ctx->internal->app_verify_cookie_cb(s, 876 D1I(s)->rcvd_cookie, cookie_len) == 0) { 877 al = SSL_AD_HANDSHAKE_FAILURE; 878 SSLerror(s, SSL_R_COOKIE_MISMATCH); 879 goto f_err; 880 } 881 /* else cookie verification succeeded */ 882 /* XXX - can d1->cookie_len > sizeof(rcvd_cookie) ? */ 883 } else if (timingsafe_memcmp(D1I(s)->rcvd_cookie, 884 D1I(s)->cookie, D1I(s)->cookie_len) != 0) { 885 /* default verification */ 886 al = SSL_AD_HANDSHAKE_FAILURE; 887 SSLerror(s, SSL_R_COOKIE_MISMATCH); 888 goto f_err; 889 } 890 cookie_valid = 1; 891 } 892 } 893 894 if (!CBS_get_u16_length_prefixed(&cbs, &cipher_suites)) 895 goto truncated; 896 897 /* XXX - This logic seems wrong... */ 898 if (CBS_len(&cipher_suites) == 0 && CBS_len(&session_id) != 0) { 899 /* we need a cipher if we are not resuming a session */ 900 al = SSL_AD_ILLEGAL_PARAMETER; 901 SSLerror(s, SSL_R_NO_CIPHERS_SPECIFIED); 902 goto f_err; 903 } 904 905 if (CBS_len(&cipher_suites) > 0) { 906 if ((ciphers = ssl_bytes_to_cipher_list(s, 907 CBS_data(&cipher_suites), CBS_len(&cipher_suites))) == NULL) 908 goto err; 909 } 910 911 /* If it is a hit, check that the cipher is in the list */ 912 if (s->internal->hit && CBS_len(&cipher_suites) > 0) { 913 j = 0; 914 id = s->session->cipher->id; 915 916 for (i = 0; i < sk_SSL_CIPHER_num(ciphers); i++) { 917 c = sk_SSL_CIPHER_value(ciphers, i); 918 if (c->id == id) { 919 j = 1; 920 break; 921 } 922 } 923 if (j == 0) { 924 /* 925 * We need to have the cipher in the cipher 926 * list if we are asked to reuse it 927 */ 928 al = SSL_AD_ILLEGAL_PARAMETER; 929 SSLerror(s, SSL_R_REQUIRED_CIPHER_MISSING); 930 goto f_err; 931 } 932 } 933 934 if (!CBS_get_u8_length_prefixed(&cbs, &compression_methods)) 935 goto truncated; 936 937 comp_null = 0; 938 while (CBS_len(&compression_methods) > 0) { 939 if (!CBS_get_u8(&compression_methods, &comp_method)) 940 goto truncated; 941 if (comp_method == 0) 942 comp_null = 1; 943 } 944 if (comp_null == 0) { 945 al = SSL_AD_DECODE_ERROR; 946 SSLerror(s, SSL_R_NO_COMPRESSION_SPECIFIED); 947 goto f_err; 948 } 949 950 p = (unsigned char *)CBS_data(&cbs); 951 952 /* TLS extensions*/ 953 if (!ssl_parse_clienthello_tlsext(s, &p, d, n, &al)) { 954 /* 'al' set by ssl_parse_clienthello_tlsext */ 955 SSLerror(s, SSL_R_PARSE_TLSEXT); 956 goto f_err; 957 } 958 if (ssl_check_clienthello_tlsext_early(s) <= 0) { 959 SSLerror(s, SSL_R_CLIENTHELLO_TLSEXT); 960 goto err; 961 } 962 963 /* 964 * Check if we want to use external pre-shared secret for this 965 * handshake for not reused session only. We need to generate 966 * server_random before calling tls_session_secret_cb in order to allow 967 * SessionTicket processing to use it in key derivation. 968 */ 969 arc4random_buf(s->s3->server_random, SSL3_RANDOM_SIZE); 970 971 if (!s->internal->hit && s->internal->tls_session_secret_cb) { 972 SSL_CIPHER *pref_cipher = NULL; 973 974 s->session->master_key_length = sizeof(s->session->master_key); 975 if (s->internal->tls_session_secret_cb(s, s->session->master_key, 976 &s->session->master_key_length, ciphers, &pref_cipher, 977 s->internal->tls_session_secret_cb_arg)) { 978 s->internal->hit = 1; 979 s->session->ciphers = ciphers; 980 s->session->verify_result = X509_V_OK; 981 982 ciphers = NULL; 983 984 /* check if some cipher was preferred by call back */ 985 pref_cipher = pref_cipher ? pref_cipher : 986 ssl3_choose_cipher(s, s->session->ciphers, 987 SSL_get_ciphers(s)); 988 if (pref_cipher == NULL) { 989 al = SSL_AD_HANDSHAKE_FAILURE; 990 SSLerror(s, SSL_R_NO_SHARED_CIPHER); 991 goto f_err; 992 } 993 994 s->session->cipher = pref_cipher; 995 996 sk_SSL_CIPHER_free(s->cipher_list); 997 sk_SSL_CIPHER_free(s->internal->cipher_list_by_id); 998 999 s->cipher_list = sk_SSL_CIPHER_dup(s->session->ciphers); 1000 s->internal->cipher_list_by_id = 1001 sk_SSL_CIPHER_dup(s->session->ciphers); 1002 } 1003 } 1004 1005 /* 1006 * Given s->session->ciphers and SSL_get_ciphers, we must 1007 * pick a cipher 1008 */ 1009 1010 if (!s->internal->hit) { 1011 sk_SSL_CIPHER_free(s->session->ciphers); 1012 s->session->ciphers = ciphers; 1013 if (ciphers == NULL) { 1014 al = SSL_AD_ILLEGAL_PARAMETER; 1015 SSLerror(s, SSL_R_NO_CIPHERS_PASSED); 1016 goto f_err; 1017 } 1018 ciphers = NULL; 1019 c = ssl3_choose_cipher(s, s->session->ciphers, 1020 SSL_get_ciphers(s)); 1021 1022 if (c == NULL) { 1023 al = SSL_AD_HANDSHAKE_FAILURE; 1024 SSLerror(s, SSL_R_NO_SHARED_CIPHER); 1025 goto f_err; 1026 } 1027 S3I(s)->hs.new_cipher = c; 1028 } else { 1029 S3I(s)->hs.new_cipher = s->session->cipher; 1030 } 1031 1032 if (!tls1_handshake_hash_init(s)) 1033 goto err; 1034 1035 alg_k = S3I(s)->hs.new_cipher->algorithm_mkey; 1036 if (!(SSL_USE_SIGALGS(s) || (alg_k & SSL_kGOST)) || 1037 !(s->verify_mode & SSL_VERIFY_PEER)) { 1038 if (!tls1_digest_cached_records(s)) { 1039 al = SSL_AD_INTERNAL_ERROR; 1040 goto f_err; 1041 } 1042 } 1043 1044 /* 1045 * We now have the following setup. 1046 * client_random 1047 * cipher_list - our prefered list of ciphers 1048 * ciphers - the clients prefered list of ciphers 1049 * compression - basically ignored right now 1050 * ssl version is set - sslv3 1051 * s->session - The ssl session has been setup. 1052 * s->internal->hit - session reuse flag 1053 * s->hs.new_cipher - the new cipher to use. 1054 */ 1055 1056 /* Handles TLS extensions that we couldn't check earlier */ 1057 if (ssl_check_clienthello_tlsext_late(s) <= 0) { 1058 SSLerror(s, SSL_R_CLIENTHELLO_TLSEXT); 1059 goto err; 1060 } 1061 1062 ret = cookie_valid ? 2 : 1; 1063 1064 if (0) { 1065 truncated: 1066 al = SSL_AD_DECODE_ERROR; 1067 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 1068 f_err: 1069 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1070 } 1071 err: 1072 sk_SSL_CIPHER_free(ciphers); 1073 1074 return (ret); 1075 } 1076 1077 int 1078 ssl3_send_server_hello(SSL *s) 1079 { 1080 unsigned char *bufend; 1081 unsigned char *p, *d; 1082 CBB cbb, session_id; 1083 size_t outlen; 1084 int sl; 1085 1086 memset(&cbb, 0, sizeof(cbb)); 1087 1088 bufend = (unsigned char *)s->internal->init_buf->data + SSL3_RT_MAX_PLAIN_LENGTH; 1089 1090 if (S3I(s)->hs.state == SSL3_ST_SW_SRVR_HELLO_A) { 1091 d = p = ssl3_handshake_msg_start(s, SSL3_MT_SERVER_HELLO); 1092 1093 if (!CBB_init_fixed(&cbb, p, bufend - p)) 1094 goto err; 1095 1096 if (!CBB_add_u16(&cbb, s->version)) 1097 goto err; 1098 if (!CBB_add_bytes(&cbb, s->s3->server_random, 1099 sizeof(s->s3->server_random))) 1100 goto err; 1101 1102 /* 1103 * There are several cases for the session ID to send 1104 * back in the server hello: 1105 * 1106 * - For session reuse from the session cache, 1107 * we send back the old session ID. 1108 * - If stateless session reuse (using a session ticket) 1109 * is successful, we send back the client's "session ID" 1110 * (which doesn't actually identify the session). 1111 * - If it is a new session, we send back the new 1112 * session ID. 1113 * - However, if we want the new session to be single-use, 1114 * we send back a 0-length session ID. 1115 * 1116 * s->internal->hit is non-zero in either case of session reuse, 1117 * so the following won't overwrite an ID that we're supposed 1118 * to send back. 1119 */ 1120 if (!(s->ctx->internal->session_cache_mode & SSL_SESS_CACHE_SERVER) 1121 && !s->internal->hit) 1122 s->session->session_id_length = 0; 1123 1124 sl = s->session->session_id_length; 1125 if (sl > (int)sizeof(s->session->session_id)) { 1126 SSLerror(s, ERR_R_INTERNAL_ERROR); 1127 goto err; 1128 } 1129 1130 if (!CBB_add_u8_length_prefixed(&cbb, &session_id)) 1131 goto err; 1132 if (!CBB_add_bytes(&session_id, s->session->session_id, sl)) 1133 goto err; 1134 1135 /* Cipher suite. */ 1136 if (!CBB_add_u16(&cbb, 1137 ssl3_cipher_get_value(S3I(s)->hs.new_cipher))) 1138 goto err; 1139 1140 /* Compression method. */ 1141 if (!CBB_add_u8(&cbb, 0)) 1142 goto err; 1143 1144 if (!CBB_finish(&cbb, NULL, &outlen)) 1145 goto err; 1146 1147 if ((p = ssl_add_serverhello_tlsext(s, p + outlen, 1148 bufend)) == NULL) { 1149 SSLerror(s, ERR_R_INTERNAL_ERROR); 1150 goto err; 1151 } 1152 1153 ssl3_handshake_msg_finish(s, p - d); 1154 } 1155 1156 /* SSL3_ST_SW_SRVR_HELLO_B */ 1157 return (ssl3_handshake_write(s)); 1158 1159 err: 1160 CBB_cleanup(&cbb); 1161 1162 return (-1); 1163 } 1164 1165 int 1166 ssl3_send_server_done(SSL *s) 1167 { 1168 CBB cbb, done; 1169 1170 memset(&cbb, 0, sizeof(cbb)); 1171 1172 if (S3I(s)->hs.state == SSL3_ST_SW_SRVR_DONE_A) { 1173 if (!ssl3_handshake_msg_start_cbb(s, &cbb, &done, 1174 SSL3_MT_SERVER_DONE)) 1175 goto err; 1176 if (!ssl3_handshake_msg_finish_cbb(s, &cbb)) 1177 goto err; 1178 1179 S3I(s)->hs.state = SSL3_ST_SW_SRVR_DONE_B; 1180 } 1181 1182 /* SSL3_ST_SW_SRVR_DONE_B */ 1183 return (ssl3_handshake_write(s)); 1184 1185 err: 1186 CBB_cleanup(&cbb); 1187 1188 return (-1); 1189 } 1190 1191 int 1192 ssl3_send_server_kex_dhe(SSL *s, CBB *cbb) 1193 { 1194 CBB dh_p, dh_g, dh_Ys; 1195 DH *dh = NULL, *dhp; 1196 unsigned char *data; 1197 int al; 1198 1199 if (s->cert->dh_tmp_auto != 0) { 1200 if ((dhp = ssl_get_auto_dh(s)) == NULL) { 1201 al = SSL_AD_INTERNAL_ERROR; 1202 SSLerror(s, ERR_R_INTERNAL_ERROR); 1203 goto f_err; 1204 } 1205 } else 1206 dhp = s->cert->dh_tmp; 1207 1208 if (dhp == NULL && s->cert->dh_tmp_cb != NULL) 1209 dhp = s->cert->dh_tmp_cb(s, 0, 1210 SSL_C_PKEYLENGTH(S3I(s)->hs.new_cipher)); 1211 1212 if (dhp == NULL) { 1213 al = SSL_AD_HANDSHAKE_FAILURE; 1214 SSLerror(s, SSL_R_MISSING_TMP_DH_KEY); 1215 goto f_err; 1216 } 1217 1218 if (S3I(s)->tmp.dh != NULL) { 1219 SSLerror(s, ERR_R_INTERNAL_ERROR); 1220 goto err; 1221 } 1222 1223 if (s->cert->dh_tmp_auto != 0) { 1224 dh = dhp; 1225 } else if ((dh = DHparams_dup(dhp)) == NULL) { 1226 SSLerror(s, ERR_R_DH_LIB); 1227 goto err; 1228 } 1229 S3I(s)->tmp.dh = dh; 1230 if (!DH_generate_key(dh)) { 1231 SSLerror(s, ERR_R_DH_LIB); 1232 goto err; 1233 } 1234 1235 /* 1236 * Serialize the DH parameters and public key. 1237 */ 1238 if (!CBB_add_u16_length_prefixed(cbb, &dh_p)) 1239 goto err; 1240 if (!CBB_add_space(&dh_p, &data, BN_num_bytes(dh->p))) 1241 goto err; 1242 BN_bn2bin(dh->p, data); 1243 1244 if (!CBB_add_u16_length_prefixed(cbb, &dh_g)) 1245 goto err; 1246 if (!CBB_add_space(&dh_g, &data, BN_num_bytes(dh->g))) 1247 goto err; 1248 BN_bn2bin(dh->g, data); 1249 1250 if (!CBB_add_u16_length_prefixed(cbb, &dh_Ys)) 1251 goto err; 1252 if (!CBB_add_space(&dh_Ys, &data, BN_num_bytes(dh->pub_key))) 1253 goto err; 1254 BN_bn2bin(dh->pub_key, data); 1255 1256 if (!CBB_flush(cbb)) 1257 goto err; 1258 1259 return (1); 1260 1261 f_err: 1262 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1263 err: 1264 return (-1); 1265 } 1266 1267 static int 1268 ssl3_send_server_kex_ecdhe_ecp(SSL *s, int nid, CBB *cbb) 1269 { 1270 CBB ecpoint; 1271 unsigned char *data; 1272 EC_KEY *ecdh = NULL, *ecdhp; 1273 const EC_GROUP *group; 1274 int encoded_len = 0; 1275 int curve_id = 0; 1276 BN_CTX *bn_ctx = NULL; 1277 int al; 1278 1279 ecdhp = s->cert->ecdh_tmp; 1280 if (s->cert->ecdh_tmp_auto != 0) { 1281 if (nid != NID_undef) 1282 ecdhp = EC_KEY_new_by_curve_name(nid); 1283 } else if (ecdhp == NULL && s->cert->ecdh_tmp_cb != NULL) { 1284 ecdhp = s->cert->ecdh_tmp_cb(s, 0, 1285 SSL_C_PKEYLENGTH(S3I(s)->hs.new_cipher)); 1286 } 1287 if (ecdhp == NULL) { 1288 al = SSL_AD_HANDSHAKE_FAILURE; 1289 SSLerror(s, SSL_R_MISSING_TMP_ECDH_KEY); 1290 goto f_err; 1291 } 1292 1293 if (S3I(s)->tmp.ecdh != NULL) { 1294 SSLerror(s, ERR_R_INTERNAL_ERROR); 1295 goto err; 1296 } 1297 1298 /* Duplicate the ECDH structure. */ 1299 if (s->cert->ecdh_tmp_auto != 0) { 1300 ecdh = ecdhp; 1301 } else if ((ecdh = EC_KEY_dup(ecdhp)) == NULL) { 1302 SSLerror(s, ERR_R_ECDH_LIB); 1303 goto err; 1304 } 1305 S3I(s)->tmp.ecdh = ecdh; 1306 1307 if ((EC_KEY_get0_public_key(ecdh) == NULL) || 1308 (EC_KEY_get0_private_key(ecdh) == NULL) || 1309 (s->internal->options & SSL_OP_SINGLE_ECDH_USE)) { 1310 if (!EC_KEY_generate_key(ecdh)) { 1311 SSLerror(s, ERR_R_ECDH_LIB); 1312 goto err; 1313 } 1314 } 1315 1316 if (((group = EC_KEY_get0_group(ecdh)) == NULL) || 1317 (EC_KEY_get0_public_key(ecdh) == NULL) || 1318 (EC_KEY_get0_private_key(ecdh) == NULL)) { 1319 SSLerror(s, ERR_R_ECDH_LIB); 1320 goto err; 1321 } 1322 1323 /* 1324 * Only named curves are supported in ECDH ephemeral key exchanges. 1325 * For supported named curves, curve_id is non-zero. 1326 */ 1327 if ((curve_id = tls1_ec_nid2curve_id( 1328 EC_GROUP_get_curve_name(group))) == 0) { 1329 SSLerror(s, SSL_R_UNSUPPORTED_ELLIPTIC_CURVE); 1330 goto err; 1331 } 1332 1333 /* 1334 * Encode the public key. First check the size of encoding and 1335 * allocate memory accordingly. 1336 */ 1337 encoded_len = EC_POINT_point2oct(group, EC_KEY_get0_public_key(ecdh), 1338 POINT_CONVERSION_UNCOMPRESSED, NULL, 0, NULL); 1339 if (encoded_len == 0) { 1340 SSLerror(s, ERR_R_ECDH_LIB); 1341 goto err; 1342 } 1343 if ((bn_ctx = BN_CTX_new()) == NULL) { 1344 SSLerror(s, ERR_R_MALLOC_FAILURE); 1345 goto err; 1346 } 1347 1348 /* 1349 * Only named curves are supported in ECDH ephemeral key exchanges. 1350 * In this case the ServerKeyExchange message has: 1351 * [1 byte CurveType], [2 byte CurveName] 1352 * [1 byte length of encoded point], followed by 1353 * the actual encoded point itself. 1354 */ 1355 if (!CBB_add_u8(cbb, NAMED_CURVE_TYPE)) 1356 goto err; 1357 if (!CBB_add_u16(cbb, curve_id)) 1358 goto err; 1359 if (!CBB_add_u8_length_prefixed(cbb, &ecpoint)) 1360 goto err; 1361 if (!CBB_add_space(&ecpoint, &data, encoded_len)) 1362 goto err; 1363 if (EC_POINT_point2oct(group, EC_KEY_get0_public_key(ecdh), 1364 POINT_CONVERSION_UNCOMPRESSED, data, encoded_len, bn_ctx) == 0) { 1365 SSLerror(s, ERR_R_ECDH_LIB); 1366 goto err; 1367 } 1368 if (!CBB_flush(cbb)) 1369 goto err; 1370 1371 BN_CTX_free(bn_ctx); 1372 1373 return (1); 1374 1375 f_err: 1376 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1377 err: 1378 BN_CTX_free(bn_ctx); 1379 1380 return (-1); 1381 } 1382 1383 static int 1384 ssl3_send_server_kex_ecdhe_ecx(SSL *s, int nid, CBB *cbb) 1385 { 1386 uint8_t *public_key = NULL; 1387 int curve_id; 1388 CBB ecpoint; 1389 int ret = -1; 1390 1391 /* Generate an X25519 key pair. */ 1392 if (S3I(s)->tmp.x25519 != NULL) { 1393 SSLerror(s, ERR_R_INTERNAL_ERROR); 1394 goto err; 1395 } 1396 if ((S3I(s)->tmp.x25519 = malloc(X25519_KEY_LENGTH)) == NULL) 1397 goto err; 1398 if ((public_key = malloc(X25519_KEY_LENGTH)) == NULL) 1399 goto err; 1400 X25519_keypair(public_key, S3I(s)->tmp.x25519); 1401 1402 /* Serialize public key. */ 1403 if ((curve_id = tls1_ec_nid2curve_id(nid)) == 0) { 1404 SSLerror(s, SSL_R_UNSUPPORTED_ELLIPTIC_CURVE); 1405 goto err; 1406 } 1407 1408 if (!CBB_add_u8(cbb, NAMED_CURVE_TYPE)) 1409 goto err; 1410 if (!CBB_add_u16(cbb, curve_id)) 1411 goto err; 1412 if (!CBB_add_u8_length_prefixed(cbb, &ecpoint)) 1413 goto err; 1414 if (!CBB_add_bytes(&ecpoint, public_key, X25519_KEY_LENGTH)) 1415 goto err; 1416 if (!CBB_flush(cbb)) 1417 goto err; 1418 1419 ret = 1; 1420 1421 err: 1422 free(public_key); 1423 1424 return (ret); 1425 } 1426 1427 static int 1428 ssl3_send_server_kex_ecdhe(SSL *s, CBB *cbb) 1429 { 1430 int nid; 1431 1432 nid = tls1_get_shared_curve(s); 1433 1434 if (s->cert->ecdh_tmp_auto != 0 && nid == NID_X25519) 1435 return ssl3_send_server_kex_ecdhe_ecx(s, nid, cbb); 1436 1437 return ssl3_send_server_kex_ecdhe_ecp(s, nid, cbb); 1438 } 1439 1440 int 1441 ssl3_send_server_key_exchange(SSL *s) 1442 { 1443 CBB cbb; 1444 unsigned char *params = NULL; 1445 size_t params_len; 1446 unsigned char *q; 1447 unsigned char md_buf[MD5_DIGEST_LENGTH + SHA_DIGEST_LENGTH]; 1448 unsigned int u; 1449 EVP_PKEY *pkey; 1450 const EVP_MD *md = NULL; 1451 unsigned char *p, *d; 1452 int al, i, j, n, kn; 1453 unsigned long type; 1454 BUF_MEM *buf; 1455 EVP_MD_CTX md_ctx; 1456 1457 memset(&cbb, 0, sizeof(cbb)); 1458 1459 EVP_MD_CTX_init(&md_ctx); 1460 if (S3I(s)->hs.state == SSL3_ST_SW_KEY_EXCH_A) { 1461 type = S3I(s)->hs.new_cipher->algorithm_mkey; 1462 1463 buf = s->internal->init_buf; 1464 1465 if (!CBB_init(&cbb, 0)) 1466 goto err; 1467 1468 if (type & SSL_kDHE) { 1469 if (ssl3_send_server_kex_dhe(s, &cbb) != 1) 1470 goto err; 1471 } else if (type & SSL_kECDHE) { 1472 if (ssl3_send_server_kex_ecdhe(s, &cbb) != 1) 1473 goto err; 1474 } else { 1475 al = SSL_AD_HANDSHAKE_FAILURE; 1476 SSLerror(s, SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE); 1477 goto f_err; 1478 } 1479 1480 if (!CBB_finish(&cbb, ¶ms, ¶ms_len)) 1481 goto err; 1482 1483 if (!(S3I(s)->hs.new_cipher->algorithm_auth & SSL_aNULL)) { 1484 if ((pkey = ssl_get_sign_pkey( 1485 s, S3I(s)->hs.new_cipher, &md)) == NULL) { 1486 al = SSL_AD_DECODE_ERROR; 1487 goto f_err; 1488 } 1489 kn = EVP_PKEY_size(pkey); 1490 } else { 1491 pkey = NULL; 1492 kn = 0; 1493 } 1494 1495 if (!BUF_MEM_grow_clean(buf, ssl3_handshake_msg_hdr_len(s) + 1496 params_len + kn)) { 1497 SSLerror(s, ERR_LIB_BUF); 1498 goto err; 1499 } 1500 1501 d = p = ssl3_handshake_msg_start(s, 1502 SSL3_MT_SERVER_KEY_EXCHANGE); 1503 1504 memcpy(p, params, params_len); 1505 1506 free(params); 1507 params = NULL; 1508 1509 n = params_len; 1510 p += params_len; 1511 1512 /* not anonymous */ 1513 if (pkey != NULL) { 1514 /* 1515 * n is the length of the params, they start at &(d[4]) 1516 * and p points to the space at the end. 1517 */ 1518 if (pkey->type == EVP_PKEY_RSA && !SSL_USE_SIGALGS(s)) { 1519 q = md_buf; 1520 j = 0; 1521 if (!EVP_DigestInit_ex(&md_ctx, EVP_md5_sha1(), 1522 NULL)) 1523 goto err; 1524 EVP_DigestUpdate(&md_ctx, s->s3->client_random, 1525 SSL3_RANDOM_SIZE); 1526 EVP_DigestUpdate(&md_ctx, s->s3->server_random, 1527 SSL3_RANDOM_SIZE); 1528 EVP_DigestUpdate(&md_ctx, d, n); 1529 EVP_DigestFinal_ex(&md_ctx, q, 1530 (unsigned int *)&i); 1531 q += i; 1532 j += i; 1533 if (RSA_sign(NID_md5_sha1, md_buf, j, 1534 &(p[2]), &u, pkey->pkey.rsa) <= 0) { 1535 SSLerror(s, ERR_R_RSA_LIB); 1536 goto err; 1537 } 1538 s2n(u, p); 1539 n += u + 2; 1540 } else if (md) { 1541 /* Send signature algorithm. */ 1542 if (SSL_USE_SIGALGS(s)) { 1543 if (!tls12_get_sigandhash(p, pkey, md)) { 1544 /* Should never happen */ 1545 al = SSL_AD_INTERNAL_ERROR; 1546 SSLerror(s, ERR_R_INTERNAL_ERROR); 1547 goto f_err; 1548 } 1549 p += 2; 1550 } 1551 EVP_SignInit_ex(&md_ctx, md, NULL); 1552 EVP_SignUpdate(&md_ctx, 1553 s->s3->client_random, 1554 SSL3_RANDOM_SIZE); 1555 EVP_SignUpdate(&md_ctx, 1556 s->s3->server_random, 1557 SSL3_RANDOM_SIZE); 1558 EVP_SignUpdate(&md_ctx, d, n); 1559 if (!EVP_SignFinal(&md_ctx, &p[2], 1560 (unsigned int *)&i, pkey)) { 1561 SSLerror(s, ERR_R_EVP_LIB); 1562 goto err; 1563 } 1564 s2n(i, p); 1565 n += i + 2; 1566 if (SSL_USE_SIGALGS(s)) 1567 n += 2; 1568 } else { 1569 /* Is this error check actually needed? */ 1570 al = SSL_AD_HANDSHAKE_FAILURE; 1571 SSLerror(s, SSL_R_UNKNOWN_PKEY_TYPE); 1572 goto f_err; 1573 } 1574 } 1575 1576 ssl3_handshake_msg_finish(s, n); 1577 } 1578 1579 S3I(s)->hs.state = SSL3_ST_SW_KEY_EXCH_B; 1580 1581 EVP_MD_CTX_cleanup(&md_ctx); 1582 1583 return (ssl3_handshake_write(s)); 1584 1585 f_err: 1586 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1587 err: 1588 free(params); 1589 EVP_MD_CTX_cleanup(&md_ctx); 1590 CBB_cleanup(&cbb); 1591 1592 return (-1); 1593 } 1594 1595 int 1596 ssl3_send_certificate_request(SSL *s) 1597 { 1598 unsigned char *p, *d; 1599 int i, j, nl, off, n; 1600 STACK_OF(X509_NAME) *sk = NULL; 1601 X509_NAME *name; 1602 BUF_MEM *buf; 1603 1604 if (S3I(s)->hs.state == SSL3_ST_SW_CERT_REQ_A) { 1605 buf = s->internal->init_buf; 1606 1607 d = p = ssl3_handshake_msg_start(s, 1608 SSL3_MT_CERTIFICATE_REQUEST); 1609 1610 /* get the list of acceptable cert types */ 1611 p++; 1612 n = ssl3_get_req_cert_type(s, p); 1613 d[0] = n; 1614 p += n; 1615 n++; 1616 1617 if (SSL_USE_SIGALGS(s)) { 1618 nl = tls12_get_req_sig_algs(s, p + 2); 1619 s2n(nl, p); 1620 p += nl + 2; 1621 n += nl + 2; 1622 } 1623 1624 off = n; 1625 p += 2; 1626 n += 2; 1627 1628 sk = SSL_get_client_CA_list(s); 1629 nl = 0; 1630 if (sk != NULL) { 1631 for (i = 0; i < sk_X509_NAME_num(sk); i++) { 1632 name = sk_X509_NAME_value(sk, i); 1633 j = i2d_X509_NAME(name, NULL); 1634 if (!BUF_MEM_grow_clean(buf, 1635 ssl3_handshake_msg_hdr_len(s) + n + j 1636 + 2)) { 1637 SSLerror(s, ERR_R_BUF_LIB); 1638 goto err; 1639 } 1640 p = ssl3_handshake_msg_start(s, 1641 SSL3_MT_CERTIFICATE_REQUEST) + n; 1642 s2n(j, p); 1643 i2d_X509_NAME(name, &p); 1644 n += 2 + j; 1645 nl += 2 + j; 1646 } 1647 } 1648 /* else no CA names */ 1649 p = ssl3_handshake_msg_start(s, 1650 SSL3_MT_CERTIFICATE_REQUEST) + off; 1651 s2n(nl, p); 1652 1653 ssl3_handshake_msg_finish(s, n); 1654 1655 S3I(s)->hs.state = SSL3_ST_SW_CERT_REQ_B; 1656 } 1657 1658 /* SSL3_ST_SW_CERT_REQ_B */ 1659 return (ssl3_handshake_write(s)); 1660 err: 1661 return (-1); 1662 } 1663 1664 static int 1665 ssl3_get_client_kex_rsa(SSL *s, unsigned char *p, long n) 1666 { 1667 unsigned char fakekey[SSL_MAX_MASTER_KEY_LENGTH]; 1668 unsigned char *d; 1669 RSA *rsa = NULL; 1670 EVP_PKEY *pkey = NULL; 1671 int i, al; 1672 1673 d = p; 1674 1675 arc4random_buf(fakekey, sizeof(fakekey)); 1676 fakekey[0] = s->client_version >> 8; 1677 fakekey[1] = s->client_version & 0xff; 1678 1679 pkey = s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey; 1680 if ((pkey == NULL) || (pkey->type != EVP_PKEY_RSA) || 1681 (pkey->pkey.rsa == NULL)) { 1682 al = SSL_AD_HANDSHAKE_FAILURE; 1683 SSLerror(s, SSL_R_MISSING_RSA_CERTIFICATE); 1684 goto f_err; 1685 } 1686 rsa = pkey->pkey.rsa; 1687 1688 if (2 > n) 1689 goto truncated; 1690 n2s(p, i); 1691 if (n != i + 2) { 1692 SSLerror(s, SSL_R_TLS_RSA_ENCRYPTED_VALUE_LENGTH_IS_WRONG); 1693 goto err; 1694 } else 1695 n = i; 1696 1697 i = RSA_private_decrypt((int)n, p, p, rsa, RSA_PKCS1_PADDING); 1698 1699 ERR_clear_error(); 1700 1701 al = -1; 1702 1703 if (i != SSL_MAX_MASTER_KEY_LENGTH) { 1704 al = SSL_AD_DECODE_ERROR; 1705 /* SSLerror(s, SSL_R_BAD_RSA_DECRYPT); */ 1706 } 1707 1708 if (p - d + 2 > n) /* needed in the SSL3 case */ 1709 goto truncated; 1710 if ((al == -1) && !((p[0] == (s->client_version >> 8)) && 1711 (p[1] == (s->client_version & 0xff)))) { 1712 /* 1713 * The premaster secret must contain the same version 1714 * number as the ClientHello to detect version rollback 1715 * attacks (strangely, the protocol does not offer such 1716 * protection for DH ciphersuites). 1717 * However, buggy clients exist that send the negotiated 1718 * protocol version instead if the server does not 1719 * support the requested protocol version. 1720 * If SSL_OP_TLS_ROLLBACK_BUG is set, tolerate such 1721 * clients. 1722 */ 1723 if (!((s->internal->options & SSL_OP_TLS_ROLLBACK_BUG) && 1724 (p[0] == (s->version >> 8)) && 1725 (p[1] == (s->version & 0xff)))) { 1726 al = SSL_AD_DECODE_ERROR; 1727 /* SSLerror(s, SSL_R_BAD_PROTOCOL_VERSION_NUMBER); */ 1728 1729 /* 1730 * The Klima-Pokorny-Rosa extension of 1731 * Bleichenbacher's attack 1732 * (http://eprint.iacr.org/2003/052/) exploits 1733 * the version number check as a "bad version 1734 * oracle" -- an alert would reveal that the 1735 * plaintext corresponding to some ciphertext 1736 * made up by the adversary is properly 1737 * formatted except that the version number is 1738 * wrong. 1739 * To avoid such attacks, we should treat this 1740 * just like any other decryption error. 1741 */ 1742 } 1743 } 1744 1745 if (al != -1) { 1746 /* 1747 * Some decryption failure -- use random value instead 1748 * as countermeasure against Bleichenbacher's attack 1749 * on PKCS #1 v1.5 RSA padding (see RFC 2246, 1750 * section 7.4.7.1). 1751 */ 1752 i = SSL_MAX_MASTER_KEY_LENGTH; 1753 p = fakekey; 1754 } 1755 1756 s->session->master_key_length = 1757 tls1_generate_master_secret(s, 1758 s->session->master_key, p, i); 1759 1760 explicit_bzero(p, i); 1761 1762 return (1); 1763 truncated: 1764 al = SSL_AD_DECODE_ERROR; 1765 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 1766 f_err: 1767 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1768 err: 1769 return (-1); 1770 } 1771 1772 static int 1773 ssl3_get_client_kex_dhe(SSL *s, unsigned char *p, long n) 1774 { 1775 BIGNUM *bn = NULL; 1776 int key_size, al; 1777 CBS cbs, dh_Yc; 1778 DH *dh; 1779 1780 if (n < 0) 1781 goto err; 1782 1783 CBS_init(&cbs, p, n); 1784 1785 if (!CBS_get_u16_length_prefixed(&cbs, &dh_Yc)) 1786 goto truncated; 1787 1788 if (CBS_len(&cbs) != 0) 1789 goto truncated; 1790 1791 if (S3I(s)->tmp.dh == NULL) { 1792 al = SSL_AD_HANDSHAKE_FAILURE; 1793 SSLerror(s, SSL_R_MISSING_TMP_DH_KEY); 1794 goto f_err; 1795 } 1796 dh = S3I(s)->tmp.dh; 1797 1798 if ((bn = BN_bin2bn(CBS_data(&dh_Yc), CBS_len(&dh_Yc), NULL)) == NULL) { 1799 SSLerror(s, SSL_R_BN_LIB); 1800 goto err; 1801 } 1802 1803 key_size = DH_compute_key(p, bn, dh); 1804 if (key_size <= 0) { 1805 SSLerror(s, ERR_R_DH_LIB); 1806 BN_clear_free(bn); 1807 goto err; 1808 } 1809 1810 s->session->master_key_length = 1811 tls1_generate_master_secret( 1812 s, s->session->master_key, p, key_size); 1813 1814 explicit_bzero(p, key_size); 1815 1816 DH_free(S3I(s)->tmp.dh); 1817 S3I(s)->tmp.dh = NULL; 1818 1819 BN_clear_free(bn); 1820 1821 return (1); 1822 1823 truncated: 1824 al = SSL_AD_DECODE_ERROR; 1825 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 1826 f_err: 1827 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1828 err: 1829 return (-1); 1830 } 1831 1832 static int 1833 ssl3_get_client_kex_ecdhe_ecp(SSL *s, unsigned char *p, long n) 1834 { 1835 EC_KEY *srvr_ecdh = NULL; 1836 EVP_PKEY *clnt_pub_pkey = NULL; 1837 EC_POINT *clnt_ecpoint = NULL; 1838 BN_CTX *bn_ctx = NULL; 1839 int i, al; 1840 1841 int ret = 1; 1842 int key_size; 1843 const EC_KEY *tkey; 1844 const EC_GROUP *group; 1845 const BIGNUM *priv_key; 1846 1847 /* Initialize structures for server's ECDH key pair. */ 1848 if ((srvr_ecdh = EC_KEY_new()) == NULL) { 1849 SSLerror(s, ERR_R_MALLOC_FAILURE); 1850 goto err; 1851 } 1852 1853 /* 1854 * Use the ephemeral values we saved when 1855 * generating the ServerKeyExchange message. 1856 */ 1857 tkey = S3I(s)->tmp.ecdh; 1858 1859 group = EC_KEY_get0_group(tkey); 1860 priv_key = EC_KEY_get0_private_key(tkey); 1861 1862 if (!EC_KEY_set_group(srvr_ecdh, group) || 1863 !EC_KEY_set_private_key(srvr_ecdh, priv_key)) { 1864 SSLerror(s, ERR_R_EC_LIB); 1865 goto err; 1866 } 1867 1868 /* Let's get client's public key */ 1869 if ((clnt_ecpoint = EC_POINT_new(group)) == NULL) { 1870 SSLerror(s, ERR_R_MALLOC_FAILURE); 1871 goto err; 1872 } 1873 1874 if (n == 0L) { 1875 /* Client Publickey was in Client Certificate */ 1876 if (((clnt_pub_pkey = X509_get_pubkey( 1877 s->session->peer)) == NULL) || 1878 (clnt_pub_pkey->type != EVP_PKEY_EC)) { 1879 /* 1880 * XXX: For now, we do not support client 1881 * authentication using ECDH certificates 1882 * so this branch (n == 0L) of the code is 1883 * never executed. When that support is 1884 * added, we ought to ensure the key 1885 * received in the certificate is 1886 * authorized for key agreement. 1887 * ECDH_compute_key implicitly checks that 1888 * the two ECDH shares are for the same 1889 * group. 1890 */ 1891 al = SSL_AD_HANDSHAKE_FAILURE; 1892 SSLerror(s, SSL_R_UNABLE_TO_DECODE_ECDH_CERTS); 1893 goto f_err; 1894 } 1895 1896 if (EC_POINT_copy(clnt_ecpoint, 1897 EC_KEY_get0_public_key(clnt_pub_pkey->pkey.ec)) 1898 == 0) { 1899 SSLerror(s, ERR_R_EC_LIB); 1900 goto err; 1901 } 1902 ret = 2; /* Skip certificate verify processing */ 1903 } else { 1904 /* 1905 * Get client's public key from encoded point 1906 * in the ClientKeyExchange message. 1907 */ 1908 if ((bn_ctx = BN_CTX_new()) == NULL) { 1909 SSLerror(s, ERR_R_MALLOC_FAILURE); 1910 goto err; 1911 } 1912 1913 /* Get encoded point length */ 1914 i = *p; 1915 1916 p += 1; 1917 if (n != 1 + i) { 1918 SSLerror(s, ERR_R_EC_LIB); 1919 goto err; 1920 } 1921 if (EC_POINT_oct2point(group, 1922 clnt_ecpoint, p, i, bn_ctx) == 0) { 1923 SSLerror(s, ERR_R_EC_LIB); 1924 goto err; 1925 } 1926 /* 1927 * p is pointing to somewhere in the buffer 1928 * currently, so set it to the start. 1929 */ 1930 p = (unsigned char *)s->internal->init_buf->data; 1931 } 1932 1933 /* Compute the shared pre-master secret */ 1934 key_size = ECDH_size(srvr_ecdh); 1935 if (key_size <= 0) { 1936 SSLerror(s, ERR_R_ECDH_LIB); 1937 goto err; 1938 } 1939 i = ECDH_compute_key(p, key_size, clnt_ecpoint, srvr_ecdh, 1940 NULL); 1941 if (i <= 0) { 1942 SSLerror(s, ERR_R_ECDH_LIB); 1943 goto err; 1944 } 1945 1946 EVP_PKEY_free(clnt_pub_pkey); 1947 EC_POINT_free(clnt_ecpoint); 1948 EC_KEY_free(srvr_ecdh); 1949 BN_CTX_free(bn_ctx); 1950 EC_KEY_free(S3I(s)->tmp.ecdh); 1951 S3I(s)->tmp.ecdh = NULL; 1952 1953 /* Compute the master secret */ 1954 s->session->master_key_length = 1955 tls1_generate_master_secret( 1956 s, s->session->master_key, p, i); 1957 1958 explicit_bzero(p, i); 1959 return (ret); 1960 1961 f_err: 1962 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1963 err: 1964 EVP_PKEY_free(clnt_pub_pkey); 1965 EC_POINT_free(clnt_ecpoint); 1966 EC_KEY_free(srvr_ecdh); 1967 BN_CTX_free(bn_ctx); 1968 return (-1); 1969 } 1970 1971 static int 1972 ssl3_get_client_kex_ecdhe_ecx(SSL *s, unsigned char *p, long n) 1973 { 1974 uint8_t *shared_key = NULL; 1975 CBS cbs, ecpoint; 1976 int ret = -1; 1977 1978 if (n < 0) 1979 goto err; 1980 1981 CBS_init(&cbs, p, n); 1982 if (!CBS_get_u8_length_prefixed(&cbs, &ecpoint)) 1983 goto err; 1984 if (CBS_len(&ecpoint) != X25519_KEY_LENGTH) 1985 goto err; 1986 1987 if ((shared_key = malloc(X25519_KEY_LENGTH)) == NULL) 1988 goto err; 1989 if (!X25519(shared_key, S3I(s)->tmp.x25519, CBS_data(&ecpoint))) 1990 goto err; 1991 1992 freezero(S3I(s)->tmp.x25519, X25519_KEY_LENGTH); 1993 S3I(s)->tmp.x25519 = NULL; 1994 1995 s->session->master_key_length = 1996 tls1_generate_master_secret( 1997 s, s->session->master_key, shared_key, X25519_KEY_LENGTH); 1998 1999 ret = 1; 2000 2001 err: 2002 freezero(shared_key, X25519_KEY_LENGTH); 2003 2004 return (ret); 2005 } 2006 2007 static int 2008 ssl3_get_client_kex_ecdhe(SSL *s, unsigned char *p, long n) 2009 { 2010 if (S3I(s)->tmp.x25519 != NULL) 2011 return ssl3_get_client_kex_ecdhe_ecx(s, p, n); 2012 2013 return ssl3_get_client_kex_ecdhe_ecp(s, p, n); 2014 } 2015 2016 static int 2017 ssl3_get_client_kex_gost(SSL *s, unsigned char *p, long n) 2018 { 2019 2020 EVP_PKEY_CTX *pkey_ctx; 2021 EVP_PKEY *client_pub_pkey = NULL, *pk = NULL; 2022 unsigned char premaster_secret[32], *start; 2023 size_t outlen = 32, inlen; 2024 unsigned long alg_a; 2025 int Ttag, Tclass; 2026 long Tlen; 2027 int al; 2028 int ret = 0; 2029 2030 /* Get our certificate private key*/ 2031 alg_a = S3I(s)->hs.new_cipher->algorithm_auth; 2032 if (alg_a & SSL_aGOST01) 2033 pk = s->cert->pkeys[SSL_PKEY_GOST01].privatekey; 2034 2035 pkey_ctx = EVP_PKEY_CTX_new(pk, NULL); 2036 EVP_PKEY_decrypt_init(pkey_ctx); 2037 /* 2038 * If client certificate is present and is of the same type, 2039 * maybe use it for key exchange. 2040 * Don't mind errors from EVP_PKEY_derive_set_peer, because 2041 * it is completely valid to use a client certificate for 2042 * authorization only. 2043 */ 2044 client_pub_pkey = X509_get_pubkey(s->session->peer); 2045 if (client_pub_pkey) { 2046 if (EVP_PKEY_derive_set_peer(pkey_ctx, 2047 client_pub_pkey) <= 0) 2048 ERR_clear_error(); 2049 } 2050 if (2 > n) 2051 goto truncated; 2052 /* Decrypt session key */ 2053 if (ASN1_get_object((const unsigned char **)&p, &Tlen, &Ttag, 2054 &Tclass, n) != V_ASN1_CONSTRUCTED || 2055 Ttag != V_ASN1_SEQUENCE || Tclass != V_ASN1_UNIVERSAL) { 2056 SSLerror(s, SSL_R_DECRYPTION_FAILED); 2057 goto gerr; 2058 } 2059 start = p; 2060 inlen = Tlen; 2061 if (EVP_PKEY_decrypt(pkey_ctx, premaster_secret, &outlen, 2062 start, inlen) <=0) { 2063 SSLerror(s, SSL_R_DECRYPTION_FAILED); 2064 goto gerr; 2065 } 2066 /* Generate master secret */ 2067 s->session->master_key_length = 2068 tls1_generate_master_secret( 2069 s, s->session->master_key, premaster_secret, 32); 2070 /* Check if pubkey from client certificate was used */ 2071 if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, -1, 2072 EVP_PKEY_CTRL_PEER_KEY, 2, NULL) > 0) 2073 ret = 2; 2074 else 2075 ret = 1; 2076 gerr: 2077 EVP_PKEY_free(client_pub_pkey); 2078 EVP_PKEY_CTX_free(pkey_ctx); 2079 if (ret) 2080 return (ret); 2081 else 2082 goto err; 2083 2084 truncated: 2085 al = SSL_AD_DECODE_ERROR; 2086 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 2087 ssl3_send_alert(s, SSL3_AL_FATAL, al); 2088 err: 2089 return (-1); 2090 } 2091 2092 int 2093 ssl3_get_client_key_exchange(SSL *s) 2094 { 2095 unsigned long alg_k; 2096 unsigned char *p; 2097 int al, ok; 2098 long n; 2099 2100 /* 2048 maxlen is a guess. How long a key does that permit? */ 2101 n = s->method->internal->ssl_get_message(s, SSL3_ST_SR_KEY_EXCH_A, 2102 SSL3_ST_SR_KEY_EXCH_B, SSL3_MT_CLIENT_KEY_EXCHANGE, 2048, &ok); 2103 if (!ok) 2104 return ((int)n); 2105 2106 p = (unsigned char *)s->internal->init_msg; 2107 2108 alg_k = S3I(s)->hs.new_cipher->algorithm_mkey; 2109 2110 if (alg_k & SSL_kRSA) { 2111 if (ssl3_get_client_kex_rsa(s, p, n) != 1) 2112 goto err; 2113 } else if (alg_k & SSL_kDHE) { 2114 if (ssl3_get_client_kex_dhe(s, p, n) != 1) 2115 goto err; 2116 } else if (alg_k & SSL_kECDHE) { 2117 if (ssl3_get_client_kex_ecdhe(s, p, n) != 1) 2118 goto err; 2119 } else if (alg_k & SSL_kGOST) { 2120 if (ssl3_get_client_kex_gost(s, p, n) != 1) 2121 goto err; 2122 } else { 2123 al = SSL_AD_HANDSHAKE_FAILURE; 2124 SSLerror(s, SSL_R_UNKNOWN_CIPHER_TYPE); 2125 goto f_err; 2126 } 2127 2128 return (1); 2129 2130 f_err: 2131 ssl3_send_alert(s, SSL3_AL_FATAL, al); 2132 err: 2133 return (-1); 2134 } 2135 2136 int 2137 ssl3_get_cert_verify(SSL *s) 2138 { 2139 EVP_PKEY *pkey = NULL; 2140 unsigned char *p; 2141 int al, ok, ret = 0; 2142 long n; 2143 int type = 0, i, j; 2144 X509 *peer; 2145 const EVP_MD *md = NULL; 2146 EVP_MD_CTX mctx; 2147 EVP_MD_CTX_init(&mctx); 2148 2149 n = s->method->internal->ssl_get_message(s, SSL3_ST_SR_CERT_VRFY_A, 2150 SSL3_ST_SR_CERT_VRFY_B, -1, SSL3_RT_MAX_PLAIN_LENGTH, &ok); 2151 if (!ok) 2152 return ((int)n); 2153 2154 if (s->session->peer != NULL) { 2155 peer = s->session->peer; 2156 pkey = X509_get_pubkey(peer); 2157 type = X509_certificate_type(peer, pkey); 2158 } else { 2159 peer = NULL; 2160 pkey = NULL; 2161 } 2162 2163 if (S3I(s)->tmp.message_type != SSL3_MT_CERTIFICATE_VERIFY) { 2164 S3I(s)->tmp.reuse_message = 1; 2165 if (peer != NULL) { 2166 al = SSL_AD_UNEXPECTED_MESSAGE; 2167 SSLerror(s, SSL_R_MISSING_VERIFY_MESSAGE); 2168 goto f_err; 2169 } 2170 ret = 1; 2171 goto end; 2172 } 2173 2174 if (peer == NULL) { 2175 SSLerror(s, SSL_R_NO_CLIENT_CERT_RECEIVED); 2176 al = SSL_AD_UNEXPECTED_MESSAGE; 2177 goto f_err; 2178 } 2179 2180 if (!(type & EVP_PKT_SIGN)) { 2181 SSLerror(s, SSL_R_SIGNATURE_FOR_NON_SIGNING_CERTIFICATE); 2182 al = SSL_AD_ILLEGAL_PARAMETER; 2183 goto f_err; 2184 } 2185 2186 if (S3I(s)->change_cipher_spec) { 2187 SSLerror(s, SSL_R_CCS_RECEIVED_EARLY); 2188 al = SSL_AD_UNEXPECTED_MESSAGE; 2189 goto f_err; 2190 } 2191 2192 /* we now have a signature that we need to verify */ 2193 p = (unsigned char *)s->internal->init_msg; 2194 /* 2195 * Check for broken implementations of GOST ciphersuites. 2196 * 2197 * If key is GOST and n is exactly 64, it is a bare 2198 * signature without length field. 2199 */ 2200 if (n == 64 && (pkey->type == NID_id_GostR3410_94 || 2201 pkey->type == NID_id_GostR3410_2001) ) { 2202 i = 64; 2203 } else { 2204 if (SSL_USE_SIGALGS(s)) { 2205 int sigalg = tls12_get_sigid(pkey); 2206 /* Should never happen */ 2207 if (sigalg == -1) { 2208 SSLerror(s, ERR_R_INTERNAL_ERROR); 2209 al = SSL_AD_INTERNAL_ERROR; 2210 goto f_err; 2211 } 2212 if (2 > n) 2213 goto truncated; 2214 /* Check key type is consistent with signature */ 2215 if (sigalg != (int)p[1]) { 2216 SSLerror(s, SSL_R_WRONG_SIGNATURE_TYPE); 2217 al = SSL_AD_DECODE_ERROR; 2218 goto f_err; 2219 } 2220 md = tls12_get_hash(p[0]); 2221 if (md == NULL) { 2222 SSLerror(s, SSL_R_UNKNOWN_DIGEST); 2223 al = SSL_AD_DECODE_ERROR; 2224 goto f_err; 2225 } 2226 p += 2; 2227 n -= 2; 2228 } 2229 if (2 > n) 2230 goto truncated; 2231 n2s(p, i); 2232 n -= 2; 2233 if (i > n) 2234 goto truncated; 2235 } 2236 j = EVP_PKEY_size(pkey); 2237 if ((i > j) || (n > j) || (n <= 0)) { 2238 SSLerror(s, SSL_R_WRONG_SIGNATURE_SIZE); 2239 al = SSL_AD_DECODE_ERROR; 2240 goto f_err; 2241 } 2242 2243 if (SSL_USE_SIGALGS(s)) { 2244 long hdatalen = 0; 2245 void *hdata; 2246 hdatalen = BIO_get_mem_data(S3I(s)->handshake_buffer, &hdata); 2247 if (hdatalen <= 0) { 2248 SSLerror(s, ERR_R_INTERNAL_ERROR); 2249 al = SSL_AD_INTERNAL_ERROR; 2250 goto f_err; 2251 } 2252 if (!EVP_VerifyInit_ex(&mctx, md, NULL) || 2253 !EVP_VerifyUpdate(&mctx, hdata, hdatalen)) { 2254 SSLerror(s, ERR_R_EVP_LIB); 2255 al = SSL_AD_INTERNAL_ERROR; 2256 goto f_err; 2257 } 2258 2259 if (EVP_VerifyFinal(&mctx, p, i, pkey) <= 0) { 2260 al = SSL_AD_DECRYPT_ERROR; 2261 SSLerror(s, SSL_R_BAD_SIGNATURE); 2262 goto f_err; 2263 } 2264 } else 2265 if (pkey->type == EVP_PKEY_RSA) { 2266 i = RSA_verify(NID_md5_sha1, S3I(s)->tmp.cert_verify_md, 2267 MD5_DIGEST_LENGTH + SHA_DIGEST_LENGTH, p, i, 2268 pkey->pkey.rsa); 2269 if (i < 0) { 2270 al = SSL_AD_DECRYPT_ERROR; 2271 SSLerror(s, SSL_R_BAD_RSA_DECRYPT); 2272 goto f_err; 2273 } 2274 if (i == 0) { 2275 al = SSL_AD_DECRYPT_ERROR; 2276 SSLerror(s, SSL_R_BAD_RSA_SIGNATURE); 2277 goto f_err; 2278 } 2279 } else 2280 if (pkey->type == EVP_PKEY_DSA) { 2281 j = DSA_verify(pkey->save_type, 2282 &(S3I(s)->tmp.cert_verify_md[MD5_DIGEST_LENGTH]), 2283 SHA_DIGEST_LENGTH, p, i, pkey->pkey.dsa); 2284 if (j <= 0) { 2285 /* bad signature */ 2286 al = SSL_AD_DECRYPT_ERROR; 2287 SSLerror(s, SSL_R_BAD_DSA_SIGNATURE); 2288 goto f_err; 2289 } 2290 } else 2291 if (pkey->type == EVP_PKEY_EC) { 2292 j = ECDSA_verify(pkey->save_type, 2293 &(S3I(s)->tmp.cert_verify_md[MD5_DIGEST_LENGTH]), 2294 SHA_DIGEST_LENGTH, p, i, pkey->pkey.ec); 2295 if (j <= 0) { 2296 /* bad signature */ 2297 al = SSL_AD_DECRYPT_ERROR; 2298 SSLerror(s, SSL_R_BAD_ECDSA_SIGNATURE); 2299 goto f_err; 2300 } 2301 } else 2302 #ifndef OPENSSL_NO_GOST 2303 if (pkey->type == NID_id_GostR3410_94 || 2304 pkey->type == NID_id_GostR3410_2001) { 2305 long hdatalen = 0; 2306 void *hdata; 2307 unsigned char signature[128]; 2308 unsigned int siglen = sizeof(signature); 2309 int nid; 2310 EVP_PKEY_CTX *pctx; 2311 2312 hdatalen = BIO_get_mem_data(S3I(s)->handshake_buffer, &hdata); 2313 if (hdatalen <= 0) { 2314 SSLerror(s, ERR_R_INTERNAL_ERROR); 2315 al = SSL_AD_INTERNAL_ERROR; 2316 goto f_err; 2317 } 2318 if (!EVP_PKEY_get_default_digest_nid(pkey, &nid) || 2319 !(md = EVP_get_digestbynid(nid))) { 2320 SSLerror(s, ERR_R_EVP_LIB); 2321 al = SSL_AD_INTERNAL_ERROR; 2322 goto f_err; 2323 } 2324 pctx = EVP_PKEY_CTX_new(pkey, NULL); 2325 if (!pctx) { 2326 SSLerror(s, ERR_R_EVP_LIB); 2327 al = SSL_AD_INTERNAL_ERROR; 2328 goto f_err; 2329 } 2330 if (!EVP_DigestInit_ex(&mctx, md, NULL) || 2331 !EVP_DigestUpdate(&mctx, hdata, hdatalen) || 2332 !EVP_DigestFinal(&mctx, signature, &siglen) || 2333 (EVP_PKEY_verify_init(pctx) <= 0) || 2334 (EVP_PKEY_CTX_set_signature_md(pctx, md) <= 0) || 2335 (EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_VERIFY, 2336 EVP_PKEY_CTRL_GOST_SIG_FORMAT, 2337 GOST_SIG_FORMAT_RS_LE, 2338 NULL) <= 0)) { 2339 SSLerror(s, ERR_R_EVP_LIB); 2340 al = SSL_AD_INTERNAL_ERROR; 2341 EVP_PKEY_CTX_free(pctx); 2342 goto f_err; 2343 } 2344 2345 if (EVP_PKEY_verify(pctx, p, i, signature, siglen) <= 0) { 2346 al = SSL_AD_DECRYPT_ERROR; 2347 SSLerror(s, SSL_R_BAD_SIGNATURE); 2348 EVP_PKEY_CTX_free(pctx); 2349 goto f_err; 2350 } 2351 2352 EVP_PKEY_CTX_free(pctx); 2353 } else 2354 #endif 2355 { 2356 SSLerror(s, ERR_R_INTERNAL_ERROR); 2357 al = SSL_AD_UNSUPPORTED_CERTIFICATE; 2358 goto f_err; 2359 } 2360 2361 2362 ret = 1; 2363 if (0) { 2364 truncated: 2365 al = SSL_AD_DECODE_ERROR; 2366 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 2367 f_err: 2368 ssl3_send_alert(s, SSL3_AL_FATAL, al); 2369 } 2370 end: 2371 if (S3I(s)->handshake_buffer) { 2372 BIO_free(S3I(s)->handshake_buffer); 2373 S3I(s)->handshake_buffer = NULL; 2374 s->s3->flags &= ~TLS1_FLAGS_KEEP_HANDSHAKE; 2375 } 2376 EVP_MD_CTX_cleanup(&mctx); 2377 EVP_PKEY_free(pkey); 2378 return (ret); 2379 } 2380 2381 int 2382 ssl3_get_client_certificate(SSL *s) 2383 { 2384 CBS cbs, client_certs; 2385 int i, ok, al, ret = -1; 2386 X509 *x = NULL; 2387 long n; 2388 const unsigned char *q; 2389 STACK_OF(X509) *sk = NULL; 2390 2391 n = s->method->internal->ssl_get_message(s, SSL3_ST_SR_CERT_A, SSL3_ST_SR_CERT_B, 2392 -1, s->internal->max_cert_list, &ok); 2393 2394 if (!ok) 2395 return ((int)n); 2396 2397 if (S3I(s)->tmp.message_type == SSL3_MT_CLIENT_KEY_EXCHANGE) { 2398 if ((s->verify_mode & SSL_VERIFY_PEER) && 2399 (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { 2400 SSLerror(s, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); 2401 al = SSL_AD_HANDSHAKE_FAILURE; 2402 goto f_err; 2403 } 2404 /* 2405 * If tls asked for a client cert, 2406 * the client must return a 0 list. 2407 */ 2408 if (S3I(s)->tmp.cert_request) { 2409 SSLerror(s, SSL_R_TLS_PEER_DID_NOT_RESPOND_WITH_CERTIFICATE_LIST 2410 ); 2411 al = SSL_AD_UNEXPECTED_MESSAGE; 2412 goto f_err; 2413 } 2414 S3I(s)->tmp.reuse_message = 1; 2415 return (1); 2416 } 2417 2418 if (S3I(s)->tmp.message_type != SSL3_MT_CERTIFICATE) { 2419 al = SSL_AD_UNEXPECTED_MESSAGE; 2420 SSLerror(s, SSL_R_WRONG_MESSAGE_TYPE); 2421 goto f_err; 2422 } 2423 2424 if (n < 0) 2425 goto truncated; 2426 2427 CBS_init(&cbs, s->internal->init_msg, n); 2428 2429 if ((sk = sk_X509_new_null()) == NULL) { 2430 SSLerror(s, ERR_R_MALLOC_FAILURE); 2431 goto err; 2432 } 2433 2434 if (!CBS_get_u24_length_prefixed(&cbs, &client_certs) || 2435 CBS_len(&cbs) != 0) 2436 goto truncated; 2437 2438 while (CBS_len(&client_certs) > 0) { 2439 CBS cert; 2440 2441 if (!CBS_get_u24_length_prefixed(&client_certs, &cert)) { 2442 al = SSL_AD_DECODE_ERROR; 2443 SSLerror(s, SSL_R_CERT_LENGTH_MISMATCH); 2444 goto f_err; 2445 } 2446 2447 q = CBS_data(&cert); 2448 x = d2i_X509(NULL, &q, CBS_len(&cert)); 2449 if (x == NULL) { 2450 SSLerror(s, ERR_R_ASN1_LIB); 2451 goto err; 2452 } 2453 if (q != CBS_data(&cert) + CBS_len(&cert)) { 2454 al = SSL_AD_DECODE_ERROR; 2455 SSLerror(s, SSL_R_CERT_LENGTH_MISMATCH); 2456 goto f_err; 2457 } 2458 if (!sk_X509_push(sk, x)) { 2459 SSLerror(s, ERR_R_MALLOC_FAILURE); 2460 goto err; 2461 } 2462 x = NULL; 2463 } 2464 2465 if (sk_X509_num(sk) <= 0) { 2466 /* 2467 * TLS does not mind 0 certs returned. 2468 * Fail for TLS only if we required a certificate. 2469 */ 2470 if ((s->verify_mode & SSL_VERIFY_PEER) && 2471 (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { 2472 SSLerror(s, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); 2473 al = SSL_AD_HANDSHAKE_FAILURE; 2474 goto f_err; 2475 } 2476 /* No client certificate so digest cached records */ 2477 if (S3I(s)->handshake_buffer && !tls1_digest_cached_records(s)) { 2478 al = SSL_AD_INTERNAL_ERROR; 2479 goto f_err; 2480 } 2481 } else { 2482 i = ssl_verify_cert_chain(s, sk); 2483 if (i <= 0) { 2484 al = ssl_verify_alarm_type(s->verify_result); 2485 SSLerror(s, SSL_R_NO_CERTIFICATE_RETURNED); 2486 goto f_err; 2487 } 2488 } 2489 2490 X509_free(s->session->peer); 2491 s->session->peer = sk_X509_shift(sk); 2492 s->session->verify_result = s->verify_result; 2493 2494 /* 2495 * With the current implementation, sess_cert will always be NULL 2496 * when we arrive here 2497 */ 2498 if (SSI(s)->sess_cert == NULL) { 2499 SSI(s)->sess_cert = ssl_sess_cert_new(); 2500 if (SSI(s)->sess_cert == NULL) { 2501 SSLerror(s, ERR_R_MALLOC_FAILURE); 2502 goto err; 2503 } 2504 } 2505 sk_X509_pop_free(SSI(s)->sess_cert->cert_chain, X509_free); 2506 SSI(s)->sess_cert->cert_chain = sk; 2507 2508 /* 2509 * Inconsistency alert: cert_chain does *not* include the 2510 * peer's own certificate, while we do include it in s3_clnt.c 2511 */ 2512 2513 sk = NULL; 2514 2515 ret = 1; 2516 if (0) { 2517 truncated: 2518 al = SSL_AD_DECODE_ERROR; 2519 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 2520 f_err: 2521 ssl3_send_alert(s, SSL3_AL_FATAL, al); 2522 } 2523 err: 2524 X509_free(x); 2525 sk_X509_pop_free(sk, X509_free); 2526 2527 return (ret); 2528 } 2529 2530 int 2531 ssl3_send_server_certificate(SSL *s) 2532 { 2533 CBB cbb, server_cert; 2534 X509 *x; 2535 2536 /* 2537 * Server Certificate - RFC 5246, section 7.4.2. 2538 */ 2539 2540 memset(&cbb, 0, sizeof(cbb)); 2541 2542 if (S3I(s)->hs.state == SSL3_ST_SW_CERT_A) { 2543 if ((x = ssl_get_server_send_cert(s)) == NULL) { 2544 SSLerror(s, ERR_R_INTERNAL_ERROR); 2545 return (0); 2546 } 2547 2548 if (!ssl3_handshake_msg_start_cbb(s, &cbb, &server_cert, 2549 SSL3_MT_CERTIFICATE)) 2550 goto err; 2551 if (!ssl3_output_cert_chain(s, &server_cert, x)) 2552 goto err; 2553 if (!ssl3_handshake_msg_finish_cbb(s, &cbb)) 2554 goto err; 2555 2556 S3I(s)->hs.state = SSL3_ST_SW_CERT_B; 2557 } 2558 2559 /* SSL3_ST_SW_CERT_B */ 2560 return (ssl3_handshake_write(s)); 2561 2562 err: 2563 CBB_cleanup(&cbb); 2564 2565 return (0); 2566 } 2567 2568 /* send a new session ticket (not necessarily for a new session) */ 2569 int 2570 ssl3_send_newsession_ticket(SSL *s) 2571 { 2572 unsigned char *d, *p, *macstart; 2573 unsigned char *senc = NULL; 2574 const unsigned char *const_p; 2575 int len, slen_full, slen; 2576 SSL_SESSION *sess; 2577 unsigned int hlen; 2578 EVP_CIPHER_CTX ctx; 2579 HMAC_CTX hctx; 2580 SSL_CTX *tctx = s->initial_ctx; 2581 unsigned char iv[EVP_MAX_IV_LENGTH]; 2582 unsigned char key_name[16]; 2583 2584 if (S3I(s)->hs.state == SSL3_ST_SW_SESSION_TICKET_A) { 2585 /* get session encoding length */ 2586 slen_full = i2d_SSL_SESSION(s->session, NULL); 2587 /* 2588 * Some length values are 16 bits, so forget it if session is 2589 * too long 2590 */ 2591 if (slen_full > 0xFF00) 2592 goto err; 2593 senc = malloc(slen_full); 2594 if (!senc) 2595 goto err; 2596 p = senc; 2597 i2d_SSL_SESSION(s->session, &p); 2598 2599 /* 2600 * Create a fresh copy (not shared with other threads) to 2601 * clean up 2602 */ 2603 const_p = senc; 2604 sess = d2i_SSL_SESSION(NULL, &const_p, slen_full); 2605 if (sess == NULL) 2606 goto err; 2607 2608 /* ID is irrelevant for the ticket */ 2609 sess->session_id_length = 0; 2610 2611 slen = i2d_SSL_SESSION(sess, NULL); 2612 if (slen > slen_full) { 2613 /* shouldn't ever happen */ 2614 goto err; 2615 } 2616 p = senc; 2617 i2d_SSL_SESSION(sess, &p); 2618 SSL_SESSION_free(sess); 2619 2620 /* 2621 * Grow buffer if need be: the length calculation is as 2622 * follows 1 (size of message name) + 3 (message length 2623 * bytes) + 4 (ticket lifetime hint) + 2 (ticket length) + 2624 * 16 (key name) + max_iv_len (iv length) + 2625 * session_length + max_enc_block_size (max encrypted session 2626 * length) + max_md_size (HMAC). 2627 */ 2628 if (!BUF_MEM_grow(s->internal->init_buf, ssl3_handshake_msg_hdr_len(s) + 2629 22 + EVP_MAX_IV_LENGTH + EVP_MAX_BLOCK_LENGTH + 2630 EVP_MAX_MD_SIZE + slen)) 2631 goto err; 2632 2633 d = p = ssl3_handshake_msg_start(s, SSL3_MT_NEWSESSION_TICKET); 2634 2635 EVP_CIPHER_CTX_init(&ctx); 2636 HMAC_CTX_init(&hctx); 2637 2638 /* 2639 * Initialize HMAC and cipher contexts. If callback present 2640 * it does all the work otherwise use generated values 2641 * from parent ctx. 2642 */ 2643 if (tctx->internal->tlsext_ticket_key_cb) { 2644 if (tctx->internal->tlsext_ticket_key_cb(s, 2645 key_name, iv, &ctx, &hctx, 1) < 0) { 2646 EVP_CIPHER_CTX_cleanup(&ctx); 2647 goto err; 2648 } 2649 } else { 2650 arc4random_buf(iv, 16); 2651 EVP_EncryptInit_ex(&ctx, EVP_aes_128_cbc(), NULL, 2652 tctx->internal->tlsext_tick_aes_key, iv); 2653 HMAC_Init_ex(&hctx, tctx->internal->tlsext_tick_hmac_key, 2654 16, tlsext_tick_md(), NULL); 2655 memcpy(key_name, tctx->internal->tlsext_tick_key_name, 16); 2656 } 2657 2658 /* 2659 * Ticket lifetime hint (advisory only): 2660 * We leave this unspecified for resumed session 2661 * (for simplicity), and guess that tickets for new 2662 * sessions will live as long as their sessions. 2663 */ 2664 l2n(s->internal->hit ? 0 : s->session->timeout, p); 2665 2666 /* Skip ticket length for now */ 2667 p += 2; 2668 /* Output key name */ 2669 macstart = p; 2670 memcpy(p, key_name, 16); 2671 p += 16; 2672 /* output IV */ 2673 memcpy(p, iv, EVP_CIPHER_CTX_iv_length(&ctx)); 2674 p += EVP_CIPHER_CTX_iv_length(&ctx); 2675 /* Encrypt session data */ 2676 EVP_EncryptUpdate(&ctx, p, &len, senc, slen); 2677 p += len; 2678 EVP_EncryptFinal_ex(&ctx, p, &len); 2679 p += len; 2680 EVP_CIPHER_CTX_cleanup(&ctx); 2681 2682 HMAC_Update(&hctx, macstart, p - macstart); 2683 HMAC_Final(&hctx, p, &hlen); 2684 HMAC_CTX_cleanup(&hctx); 2685 p += hlen; 2686 2687 /* Now write out lengths: p points to end of data written */ 2688 /* Total length */ 2689 len = p - d; 2690 2691 /* Skip ticket lifetime hint. */ 2692 p = d + 4; 2693 s2n(len - 6, p); /* Message length */ 2694 2695 ssl3_handshake_msg_finish(s, len); 2696 2697 S3I(s)->hs.state = SSL3_ST_SW_SESSION_TICKET_B; 2698 2699 freezero(senc, slen_full); 2700 } 2701 2702 /* SSL3_ST_SW_SESSION_TICKET_B */ 2703 return (ssl3_handshake_write(s)); 2704 2705 err: 2706 freezero(senc, slen_full); 2707 2708 return (-1); 2709 } 2710 2711 int 2712 ssl3_send_cert_status(SSL *s) 2713 { 2714 CBB cbb, certstatus, ocspresp; 2715 2716 memset(&cbb, 0, sizeof(cbb)); 2717 2718 if (S3I(s)->hs.state == SSL3_ST_SW_CERT_STATUS_A) { 2719 if (!ssl3_handshake_msg_start_cbb(s, &cbb, &certstatus, 2720 SSL3_MT_CERTIFICATE_STATUS)) 2721 goto err; 2722 if (!CBB_add_u8(&certstatus, s->tlsext_status_type)) 2723 goto err; 2724 if (!CBB_add_u24_length_prefixed(&certstatus, &ocspresp)) 2725 goto err; 2726 if (!CBB_add_bytes(&ocspresp, s->internal->tlsext_ocsp_resp, 2727 s->internal->tlsext_ocsp_resplen)) 2728 goto err; 2729 if (!ssl3_handshake_msg_finish_cbb(s, &cbb)) 2730 goto err; 2731 2732 S3I(s)->hs.state = SSL3_ST_SW_CERT_STATUS_B; 2733 } 2734 2735 /* SSL3_ST_SW_CERT_STATUS_B */ 2736 return (ssl3_handshake_write(s)); 2737 2738 err: 2739 CBB_cleanup(&cbb); 2740 2741 return (-1); 2742 } 2743 2744 /* 2745 * ssl3_get_next_proto reads a Next Protocol Negotiation handshake message. 2746 * It sets the next_proto member in s if found 2747 */ 2748 int 2749 ssl3_get_next_proto(SSL *s) 2750 { 2751 CBS cbs, proto, padding; 2752 int ok; 2753 long n; 2754 size_t len; 2755 2756 /* 2757 * Clients cannot send a NextProtocol message if we didn't see the 2758 * extension in their ClientHello 2759 */ 2760 if (!S3I(s)->next_proto_neg_seen) { 2761 SSLerror(s, SSL_R_GOT_NEXT_PROTO_WITHOUT_EXTENSION); 2762 return (-1); 2763 } 2764 2765 /* 514 maxlen is enough for the payload format below */ 2766 n = s->method->internal->ssl_get_message(s, SSL3_ST_SR_NEXT_PROTO_A, 2767 SSL3_ST_SR_NEXT_PROTO_B, SSL3_MT_NEXT_PROTO, 514, &ok); 2768 if (!ok) 2769 return ((int)n); 2770 2771 /* 2772 * S3I(s)->hs.state doesn't reflect whether ChangeCipherSpec has been received 2773 * in this handshake, but S3I(s)->change_cipher_spec does (will be reset 2774 * by ssl3_get_finished). 2775 */ 2776 if (!S3I(s)->change_cipher_spec) { 2777 SSLerror(s, SSL_R_GOT_NEXT_PROTO_BEFORE_A_CCS); 2778 return (-1); 2779 } 2780 2781 if (n < 2) 2782 return (0); 2783 /* The body must be > 1 bytes long */ 2784 2785 CBS_init(&cbs, s->internal->init_msg, s->internal->init_num); 2786 2787 /* 2788 * The payload looks like: 2789 * uint8 proto_len; 2790 * uint8 proto[proto_len]; 2791 * uint8 padding_len; 2792 * uint8 padding[padding_len]; 2793 */ 2794 if (!CBS_get_u8_length_prefixed(&cbs, &proto) || 2795 !CBS_get_u8_length_prefixed(&cbs, &padding) || 2796 CBS_len(&cbs) != 0) 2797 return 0; 2798 2799 /* 2800 * XXX We should not NULL it, but this matches old behavior of not 2801 * freeing before malloc. 2802 */ 2803 s->internal->next_proto_negotiated = NULL; 2804 s->internal->next_proto_negotiated_len = 0; 2805 2806 if (!CBS_stow(&proto, &s->internal->next_proto_negotiated, &len)) { 2807 SSLerror(s, ERR_R_MALLOC_FAILURE); 2808 return (0); 2809 } 2810 s->internal->next_proto_negotiated_len = (uint8_t)len; 2811 2812 return (1); 2813 } 2814