1 /* $OpenBSD: ssl_srvr.c,v 1.79 2020/06/05 17:53:26 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_sigalgs.h" 170 #include "ssl_tlsext.h" 171 172 int 173 ssl3_accept(SSL *s) 174 { 175 void (*cb)(const SSL *ssl, int type, int val) = NULL; 176 unsigned long alg_k; 177 int ret = -1; 178 int new_state, state, skip = 0; 179 int listen = 0; 180 181 ERR_clear_error(); 182 errno = 0; 183 184 if (s->internal->info_callback != NULL) 185 cb = s->internal->info_callback; 186 else if (s->ctx->internal->info_callback != NULL) 187 cb = s->ctx->internal->info_callback; 188 189 if (SSL_IS_DTLS(s)) 190 listen = D1I(s)->listen; 191 192 /* init things to blank */ 193 s->internal->in_handshake++; 194 if (!SSL_in_init(s) || SSL_in_before(s)) 195 SSL_clear(s); 196 197 if (SSL_IS_DTLS(s)) 198 D1I(s)->listen = listen; 199 200 for (;;) { 201 state = S3I(s)->hs.state; 202 203 switch (S3I(s)->hs.state) { 204 case SSL_ST_RENEGOTIATE: 205 s->internal->renegotiate = 1; 206 /* S3I(s)->hs.state=SSL_ST_ACCEPT; */ 207 208 case SSL_ST_BEFORE: 209 case SSL_ST_ACCEPT: 210 case SSL_ST_BEFORE|SSL_ST_ACCEPT: 211 case SSL_ST_OK|SSL_ST_ACCEPT: 212 s->server = 1; 213 if (cb != NULL) 214 cb(s, SSL_CB_HANDSHAKE_START, 1); 215 216 if (SSL_IS_DTLS(s)) { 217 if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00)) { 218 SSLerror(s, ERR_R_INTERNAL_ERROR); 219 ret = -1; 220 goto end; 221 } 222 } else { 223 if ((s->version >> 8) != 3) { 224 SSLerror(s, ERR_R_INTERNAL_ERROR); 225 ret = -1; 226 goto end; 227 } 228 } 229 s->internal->type = SSL_ST_ACCEPT; 230 231 if (!ssl3_setup_init_buffer(s)) { 232 ret = -1; 233 goto end; 234 } 235 if (!ssl3_setup_buffers(s)) { 236 ret = -1; 237 goto end; 238 } 239 240 s->internal->init_num = 0; 241 242 if (S3I(s)->hs.state != SSL_ST_RENEGOTIATE) { 243 /* 244 * Ok, we now need to push on a buffering BIO 245 * so that the output is sent in a way that 246 * TCP likes :-) 247 */ 248 if (!ssl_init_wbio_buffer(s, 1)) { 249 ret = -1; 250 goto end; 251 } 252 253 if (!tls1_transcript_init(s)) { 254 ret = -1; 255 goto end; 256 } 257 258 S3I(s)->hs.state = SSL3_ST_SR_CLNT_HELLO_A; 259 s->ctx->internal->stats.sess_accept++; 260 } else if (!SSL_IS_DTLS(s) && !S3I(s)->send_connection_binding) { 261 /* 262 * Server attempting to renegotiate with 263 * client that doesn't support secure 264 * renegotiation. 265 */ 266 SSLerror(s, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED); 267 ssl3_send_alert(s, SSL3_AL_FATAL, 268 SSL_AD_HANDSHAKE_FAILURE); 269 ret = -1; 270 goto end; 271 } else { 272 /* 273 * S3I(s)->hs.state == SSL_ST_RENEGOTIATE, 274 * we will just send a HelloRequest. 275 */ 276 s->ctx->internal->stats.sess_accept_renegotiate++; 277 S3I(s)->hs.state = SSL3_ST_SW_HELLO_REQ_A; 278 } 279 break; 280 281 case SSL3_ST_SW_HELLO_REQ_A: 282 case SSL3_ST_SW_HELLO_REQ_B: 283 s->internal->shutdown = 0; 284 if (SSL_IS_DTLS(s)) { 285 dtls1_clear_record_buffer(s); 286 dtls1_start_timer(s); 287 } 288 ret = ssl3_send_hello_request(s); 289 if (ret <= 0) 290 goto end; 291 if (SSL_IS_DTLS(s)) 292 S3I(s)->hs.next_state = SSL3_ST_SR_CLNT_HELLO_A; 293 else 294 S3I(s)->hs.next_state = SSL3_ST_SW_HELLO_REQ_C; 295 S3I(s)->hs.state = SSL3_ST_SW_FLUSH; 296 s->internal->init_num = 0; 297 298 if (!tls1_transcript_init(s)) { 299 ret = -1; 300 goto end; 301 } 302 break; 303 304 case SSL3_ST_SW_HELLO_REQ_C: 305 S3I(s)->hs.state = SSL_ST_OK; 306 break; 307 308 case SSL3_ST_SR_CLNT_HELLO_A: 309 case SSL3_ST_SR_CLNT_HELLO_B: 310 case SSL3_ST_SR_CLNT_HELLO_C: 311 s->internal->shutdown = 0; 312 if (SSL_IS_DTLS(s)) { 313 ret = ssl3_get_client_hello(s); 314 if (ret <= 0) 315 goto end; 316 dtls1_stop_timer(s); 317 318 if (ret == 1 && 319 (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE)) 320 S3I(s)->hs.state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A; 321 else 322 S3I(s)->hs.state = SSL3_ST_SW_SRVR_HELLO_A; 323 324 s->internal->init_num = 0; 325 326 /* 327 * Reflect ClientHello sequence to remain 328 * stateless while listening. 329 */ 330 if (listen) { 331 memcpy(S3I(s)->write_sequence, 332 S3I(s)->read_sequence, 333 sizeof(S3I(s)->write_sequence)); 334 } 335 336 /* If we're just listening, stop here */ 337 if (listen && S3I(s)->hs.state == SSL3_ST_SW_SRVR_HELLO_A) { 338 ret = 2; 339 D1I(s)->listen = 0; 340 /* 341 * Set expected sequence numbers to 342 * continue the handshake. 343 */ 344 D1I(s)->handshake_read_seq = 2; 345 D1I(s)->handshake_write_seq = 1; 346 D1I(s)->next_handshake_write_seq = 1; 347 goto end; 348 } 349 } else { 350 if (s->internal->rwstate != SSL_X509_LOOKUP) { 351 ret = ssl3_get_client_hello(s); 352 if (ret <= 0) 353 goto end; 354 } 355 356 s->internal->renegotiate = 2; 357 S3I(s)->hs.state = SSL3_ST_SW_SRVR_HELLO_A; 358 s->internal->init_num = 0; 359 } 360 break; 361 362 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A: 363 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B: 364 ret = dtls1_send_hello_verify_request(s); 365 if (ret <= 0) 366 goto end; 367 S3I(s)->hs.state = SSL3_ST_SW_FLUSH; 368 S3I(s)->hs.next_state = SSL3_ST_SR_CLNT_HELLO_A; 369 370 /* HelloVerifyRequest resets Finished MAC. */ 371 tls1_transcript_reset(s); 372 break; 373 374 case SSL3_ST_SW_SRVR_HELLO_A: 375 case SSL3_ST_SW_SRVR_HELLO_B: 376 if (SSL_IS_DTLS(s)) { 377 s->internal->renegotiate = 2; 378 dtls1_start_timer(s); 379 } 380 ret = ssl3_send_server_hello(s); 381 if (ret <= 0) 382 goto end; 383 if (s->internal->hit) { 384 if (s->internal->tlsext_ticket_expected) 385 S3I(s)->hs.state = SSL3_ST_SW_SESSION_TICKET_A; 386 else 387 S3I(s)->hs.state = SSL3_ST_SW_CHANGE_A; 388 } else { 389 S3I(s)->hs.state = SSL3_ST_SW_CERT_A; 390 } 391 s->internal->init_num = 0; 392 break; 393 394 case SSL3_ST_SW_CERT_A: 395 case SSL3_ST_SW_CERT_B: 396 /* Check if it is anon DH or anon ECDH. */ 397 if (!(S3I(s)->hs.new_cipher->algorithm_auth & 398 SSL_aNULL)) { 399 if (SSL_IS_DTLS(s)) 400 dtls1_start_timer(s); 401 ret = ssl3_send_server_certificate(s); 402 if (ret <= 0) 403 goto end; 404 if (s->internal->tlsext_status_expected) 405 S3I(s)->hs.state = SSL3_ST_SW_CERT_STATUS_A; 406 else 407 S3I(s)->hs.state = SSL3_ST_SW_KEY_EXCH_A; 408 } else { 409 skip = 1; 410 S3I(s)->hs.state = SSL3_ST_SW_KEY_EXCH_A; 411 } 412 s->internal->init_num = 0; 413 break; 414 415 case SSL3_ST_SW_KEY_EXCH_A: 416 case SSL3_ST_SW_KEY_EXCH_B: 417 alg_k = S3I(s)->hs.new_cipher->algorithm_mkey; 418 419 /* 420 * Only send if using a DH key exchange. 421 * 422 * For ECC ciphersuites, we send a ServerKeyExchange 423 * message only if the cipher suite is ECDHE. In other 424 * cases, the server certificate contains the server's 425 * public key for key exchange. 426 */ 427 if (alg_k & (SSL_kDHE|SSL_kECDHE)) { 428 if (SSL_IS_DTLS(s)) 429 dtls1_start_timer(s); 430 ret = ssl3_send_server_key_exchange(s); 431 if (ret <= 0) 432 goto end; 433 } else 434 skip = 1; 435 436 S3I(s)->hs.state = SSL3_ST_SW_CERT_REQ_A; 437 s->internal->init_num = 0; 438 break; 439 440 case SSL3_ST_SW_CERT_REQ_A: 441 case SSL3_ST_SW_CERT_REQ_B: 442 /* 443 * Determine whether or not we need to request a 444 * certificate. 445 * 446 * Do not request a certificate if: 447 * 448 * - We did not ask for it (SSL_VERIFY_PEER is unset). 449 * 450 * - SSL_VERIFY_CLIENT_ONCE is set and we are 451 * renegotiating. 452 * 453 * - We are using an anonymous ciphersuites 454 * (see section "Certificate request" in SSL 3 drafts 455 * and in RFC 2246) ... except when the application 456 * insists on verification (against the specs, but 457 * s3_clnt.c accepts this for SSL 3). 458 */ 459 if (!(s->verify_mode & SSL_VERIFY_PEER) || 460 ((s->session->peer != NULL) && 461 (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) || 462 ((S3I(s)->hs.new_cipher->algorithm_auth & 463 SSL_aNULL) && !(s->verify_mode & 464 SSL_VERIFY_FAIL_IF_NO_PEER_CERT))) { 465 /* No cert request. */ 466 skip = 1; 467 S3I(s)->tmp.cert_request = 0; 468 S3I(s)->hs.state = SSL3_ST_SW_SRVR_DONE_A; 469 470 if (!SSL_IS_DTLS(s)) 471 tls1_transcript_free(s); 472 } else { 473 S3I(s)->tmp.cert_request = 1; 474 if (SSL_IS_DTLS(s)) 475 dtls1_start_timer(s); 476 ret = ssl3_send_certificate_request(s); 477 if (ret <= 0) 478 goto end; 479 S3I(s)->hs.state = SSL3_ST_SW_SRVR_DONE_A; 480 s->internal->init_num = 0; 481 } 482 break; 483 484 case SSL3_ST_SW_SRVR_DONE_A: 485 case SSL3_ST_SW_SRVR_DONE_B: 486 if (SSL_IS_DTLS(s)) 487 dtls1_start_timer(s); 488 ret = ssl3_send_server_done(s); 489 if (ret <= 0) 490 goto end; 491 S3I(s)->hs.next_state = SSL3_ST_SR_CERT_A; 492 S3I(s)->hs.state = SSL3_ST_SW_FLUSH; 493 s->internal->init_num = 0; 494 break; 495 496 case SSL3_ST_SW_FLUSH: 497 /* 498 * This code originally checked to see if 499 * any data was pending using BIO_CTRL_INFO 500 * and then flushed. This caused problems 501 * as documented in PR#1939. The proposed 502 * fix doesn't completely resolve this issue 503 * as buggy implementations of BIO_CTRL_PENDING 504 * still exist. So instead we just flush 505 * unconditionally. 506 */ 507 s->internal->rwstate = SSL_WRITING; 508 if (BIO_flush(s->wbio) <= 0) { 509 if (SSL_IS_DTLS(s)) { 510 /* If the write error was fatal, stop trying. */ 511 if (!BIO_should_retry(s->wbio)) { 512 s->internal->rwstate = SSL_NOTHING; 513 S3I(s)->hs.state = S3I(s)->hs.next_state; 514 } 515 } 516 ret = -1; 517 goto end; 518 } 519 s->internal->rwstate = SSL_NOTHING; 520 S3I(s)->hs.state = S3I(s)->hs.next_state; 521 break; 522 523 case SSL3_ST_SR_CERT_A: 524 case SSL3_ST_SR_CERT_B: 525 if (S3I(s)->tmp.cert_request) { 526 ret = ssl3_get_client_certificate(s); 527 if (ret <= 0) 528 goto end; 529 } 530 s->internal->init_num = 0; 531 S3I(s)->hs.state = SSL3_ST_SR_KEY_EXCH_A; 532 break; 533 534 case SSL3_ST_SR_KEY_EXCH_A: 535 case SSL3_ST_SR_KEY_EXCH_B: 536 ret = ssl3_get_client_key_exchange(s); 537 if (ret <= 0) 538 goto end; 539 540 if (SSL_IS_DTLS(s)) { 541 S3I(s)->hs.state = SSL3_ST_SR_CERT_VRFY_A; 542 s->internal->init_num = 0; 543 } 544 545 alg_k = S3I(s)->hs.new_cipher->algorithm_mkey; 546 if (ret == 2) { 547 /* 548 * For the ECDH ciphersuites when 549 * the client sends its ECDH pub key in 550 * a certificate, the CertificateVerify 551 * message is not sent. 552 * Also for GOST ciphersuites when 553 * the client uses its key from the certificate 554 * for key exchange. 555 */ 556 S3I(s)->hs.state = SSL3_ST_SR_FINISHED_A; 557 s->internal->init_num = 0; 558 } else if (SSL_USE_SIGALGS(s) || (alg_k & SSL_kGOST)) { 559 S3I(s)->hs.state = SSL3_ST_SR_CERT_VRFY_A; 560 s->internal->init_num = 0; 561 if (!s->session->peer) 562 break; 563 /* 564 * Freeze the transcript for use during client 565 * certificate verification. 566 */ 567 tls1_transcript_freeze(s); 568 } else { 569 S3I(s)->hs.state = SSL3_ST_SR_CERT_VRFY_A; 570 s->internal->init_num = 0; 571 572 tls1_transcript_free(s); 573 574 /* 575 * We need to get hashes here so if there is 576 * a client cert, it can be verified. 577 */ 578 if (!tls1_transcript_hash_value(s, 579 S3I(s)->tmp.cert_verify_md, 580 sizeof(S3I(s)->tmp.cert_verify_md), 581 NULL)) { 582 ret = -1; 583 goto end; 584 } 585 } 586 break; 587 588 case SSL3_ST_SR_CERT_VRFY_A: 589 case SSL3_ST_SR_CERT_VRFY_B: 590 if (SSL_IS_DTLS(s)) 591 D1I(s)->change_cipher_spec_ok = 1; 592 else 593 s->s3->flags |= SSL3_FLAGS_CCS_OK; 594 595 /* we should decide if we expected this one */ 596 ret = ssl3_get_cert_verify(s); 597 if (ret <= 0) 598 goto end; 599 S3I(s)->hs.state = SSL3_ST_SR_FINISHED_A; 600 s->internal->init_num = 0; 601 break; 602 603 case SSL3_ST_SR_FINISHED_A: 604 case SSL3_ST_SR_FINISHED_B: 605 if (SSL_IS_DTLS(s)) 606 D1I(s)->change_cipher_spec_ok = 1; 607 else 608 s->s3->flags |= SSL3_FLAGS_CCS_OK; 609 ret = ssl3_get_finished(s, SSL3_ST_SR_FINISHED_A, 610 SSL3_ST_SR_FINISHED_B); 611 if (ret <= 0) 612 goto end; 613 if (SSL_IS_DTLS(s)) 614 dtls1_stop_timer(s); 615 if (s->internal->hit) 616 S3I(s)->hs.state = SSL_ST_OK; 617 else if (s->internal->tlsext_ticket_expected) 618 S3I(s)->hs.state = SSL3_ST_SW_SESSION_TICKET_A; 619 else 620 S3I(s)->hs.state = SSL3_ST_SW_CHANGE_A; 621 s->internal->init_num = 0; 622 break; 623 624 case SSL3_ST_SW_SESSION_TICKET_A: 625 case SSL3_ST_SW_SESSION_TICKET_B: 626 ret = ssl3_send_newsession_ticket(s); 627 if (ret <= 0) 628 goto end; 629 S3I(s)->hs.state = SSL3_ST_SW_CHANGE_A; 630 s->internal->init_num = 0; 631 break; 632 633 case SSL3_ST_SW_CERT_STATUS_A: 634 case SSL3_ST_SW_CERT_STATUS_B: 635 ret = ssl3_send_cert_status(s); 636 if (ret <= 0) 637 goto end; 638 S3I(s)->hs.state = SSL3_ST_SW_KEY_EXCH_A; 639 s->internal->init_num = 0; 640 break; 641 642 case SSL3_ST_SW_CHANGE_A: 643 case SSL3_ST_SW_CHANGE_B: 644 s->session->cipher = S3I(s)->hs.new_cipher; 645 if (!tls1_setup_key_block(s)) { 646 ret = -1; 647 goto end; 648 } 649 650 ret = ssl3_send_change_cipher_spec(s, 651 SSL3_ST_SW_CHANGE_A, SSL3_ST_SW_CHANGE_B); 652 if (ret <= 0) 653 goto end; 654 S3I(s)->hs.state = SSL3_ST_SW_FINISHED_A; 655 s->internal->init_num = 0; 656 657 if (!tls1_change_cipher_state(s, 658 SSL3_CHANGE_CIPHER_SERVER_WRITE)) { 659 ret = -1; 660 goto end; 661 } 662 663 if (SSL_IS_DTLS(s)) 664 dtls1_reset_seq_numbers(s, SSL3_CC_WRITE); 665 break; 666 667 case SSL3_ST_SW_FINISHED_A: 668 case SSL3_ST_SW_FINISHED_B: 669 ret = ssl3_send_finished(s, 670 SSL3_ST_SW_FINISHED_A, SSL3_ST_SW_FINISHED_B, 671 TLS_MD_SERVER_FINISH_CONST, 672 TLS_MD_SERVER_FINISH_CONST_SIZE); 673 if (ret <= 0) 674 goto end; 675 S3I(s)->hs.state = SSL3_ST_SW_FLUSH; 676 if (s->internal->hit) { 677 S3I(s)->hs.next_state = SSL3_ST_SR_FINISHED_A; 678 tls1_transcript_free(s); 679 } else 680 S3I(s)->hs.next_state = SSL_ST_OK; 681 s->internal->init_num = 0; 682 break; 683 684 case SSL_ST_OK: 685 /* clean a few things up */ 686 tls1_cleanup_key_block(s); 687 688 if (S3I(s)->handshake_transcript != NULL) { 689 SSLerror(s, ERR_R_INTERNAL_ERROR); 690 ret = -1; 691 goto end; 692 } 693 694 if (!SSL_IS_DTLS(s)) { 695 BUF_MEM_free(s->internal->init_buf); 696 s->internal->init_buf = NULL; 697 } 698 699 /* remove buffering on output */ 700 ssl_free_wbio_buffer(s); 701 702 s->internal->init_num = 0; 703 704 /* Skipped if we just sent a HelloRequest. */ 705 if (s->internal->renegotiate == 2) { 706 s->internal->renegotiate = 0; 707 s->internal->new_session = 0; 708 709 ssl_update_cache(s, SSL_SESS_CACHE_SERVER); 710 711 s->ctx->internal->stats.sess_accept_good++; 712 /* s->server=1; */ 713 s->internal->handshake_func = ssl3_accept; 714 715 if (cb != NULL) 716 cb(s, SSL_CB_HANDSHAKE_DONE, 1); 717 } 718 719 ret = 1; 720 721 if (SSL_IS_DTLS(s)) { 722 /* Done handshaking, next message is client hello. */ 723 D1I(s)->handshake_read_seq = 0; 724 /* Next message is server hello. */ 725 D1I(s)->handshake_write_seq = 0; 726 D1I(s)->next_handshake_write_seq = 0; 727 } 728 goto end; 729 /* break; */ 730 731 default: 732 SSLerror(s, SSL_R_UNKNOWN_STATE); 733 ret = -1; 734 goto end; 735 /* break; */ 736 } 737 738 if (!S3I(s)->tmp.reuse_message && !skip) { 739 if (s->internal->debug) { 740 if ((ret = BIO_flush(s->wbio)) <= 0) 741 goto end; 742 } 743 744 745 if ((cb != NULL) && (S3I(s)->hs.state != state)) { 746 new_state = S3I(s)->hs.state; 747 S3I(s)->hs.state = state; 748 cb(s, SSL_CB_ACCEPT_LOOP, 1); 749 S3I(s)->hs.state = new_state; 750 } 751 } 752 skip = 0; 753 } 754 end: 755 /* BIO_flush(s->wbio); */ 756 s->internal->in_handshake--; 757 if (cb != NULL) 758 cb(s, SSL_CB_ACCEPT_EXIT, ret); 759 760 return (ret); 761 } 762 763 int 764 ssl3_send_hello_request(SSL *s) 765 { 766 CBB cbb, hello; 767 768 memset(&cbb, 0, sizeof(cbb)); 769 770 if (S3I(s)->hs.state == SSL3_ST_SW_HELLO_REQ_A) { 771 if (!ssl3_handshake_msg_start(s, &cbb, &hello, 772 SSL3_MT_HELLO_REQUEST)) 773 goto err; 774 if (!ssl3_handshake_msg_finish(s, &cbb)) 775 goto err; 776 777 S3I(s)->hs.state = SSL3_ST_SW_HELLO_REQ_B; 778 } 779 780 /* SSL3_ST_SW_HELLO_REQ_B */ 781 return (ssl3_handshake_write(s)); 782 783 err: 784 CBB_cleanup(&cbb); 785 786 return (-1); 787 } 788 789 int 790 ssl3_get_client_hello(SSL *s) 791 { 792 CBS cbs, client_random, session_id, cookie, cipher_suites; 793 CBS compression_methods; 794 uint16_t client_version; 795 uint8_t comp_method; 796 int comp_null; 797 int i, j, ok, al, ret = -1, cookie_valid = 0; 798 long n; 799 unsigned long id; 800 SSL_CIPHER *c; 801 STACK_OF(SSL_CIPHER) *ciphers = NULL; 802 unsigned long alg_k; 803 const SSL_METHOD *method; 804 uint16_t max_version, shared_version; 805 806 /* 807 * We do this so that we will respond with our native type. 808 * If we are TLSv1 and we get SSLv3, we will respond with TLSv1, 809 * This down switching should be handled by a different method. 810 * If we are SSLv3, we will respond with SSLv3, even if prompted with 811 * TLSv1. 812 */ 813 if (S3I(s)->hs.state == SSL3_ST_SR_CLNT_HELLO_A) { 814 S3I(s)->hs.state = SSL3_ST_SR_CLNT_HELLO_B; 815 } 816 817 s->internal->first_packet = 1; 818 n = ssl3_get_message(s, SSL3_ST_SR_CLNT_HELLO_B, 819 SSL3_ST_SR_CLNT_HELLO_C, SSL3_MT_CLIENT_HELLO, 820 SSL3_RT_MAX_PLAIN_LENGTH, &ok); 821 if (!ok) 822 return ((int)n); 823 s->internal->first_packet = 0; 824 825 if (n < 0) 826 goto err; 827 828 CBS_init(&cbs, s->internal->init_msg, n); 829 830 /* Parse client hello up until the extensions (if any). */ 831 if (!CBS_get_u16(&cbs, &client_version)) 832 goto truncated; 833 if (!CBS_get_bytes(&cbs, &client_random, SSL3_RANDOM_SIZE)) 834 goto truncated; 835 if (!CBS_get_u8_length_prefixed(&cbs, &session_id)) 836 goto truncated; 837 if (CBS_len(&session_id) > SSL3_SESSION_ID_SIZE) { 838 al = SSL_AD_ILLEGAL_PARAMETER; 839 SSLerror(s, SSL_R_SSL3_SESSION_ID_TOO_LONG); 840 goto f_err; 841 } 842 if (SSL_IS_DTLS(s)) { 843 if (!CBS_get_u8_length_prefixed(&cbs, &cookie)) 844 goto truncated; 845 } 846 if (!CBS_get_u16_length_prefixed(&cbs, &cipher_suites)) 847 goto truncated; 848 if (!CBS_get_u8_length_prefixed(&cbs, &compression_methods)) 849 goto truncated; 850 851 /* 852 * Use version from inside client hello, not from record header. 853 * (may differ: see RFC 2246, Appendix E, second paragraph) 854 */ 855 if (!ssl_downgrade_max_version(s, &max_version)) 856 goto err; 857 if (ssl_max_shared_version(s, client_version, &shared_version) != 1) { 858 SSLerror(s, SSL_R_WRONG_VERSION_NUMBER); 859 if ((s->client_version >> 8) == SSL3_VERSION_MAJOR && 860 !s->internal->enc_write_ctx && !s->internal->write_hash) { 861 /* 862 * Similar to ssl3_get_record, send alert using remote 863 * version number. 864 */ 865 s->version = s->client_version; 866 } 867 al = SSL_AD_PROTOCOL_VERSION; 868 goto f_err; 869 } 870 s->client_version = client_version; 871 s->version = shared_version; 872 873 if ((method = tls1_get_server_method(shared_version)) == NULL) 874 method = dtls1_get_server_method(shared_version); 875 if (method == NULL) { 876 SSLerror(s, ERR_R_INTERNAL_ERROR); 877 goto err; 878 } 879 s->method = method; 880 881 /* 882 * If we require cookies (DTLS) and this ClientHello does not contain 883 * one, just return since we do not want to allocate any memory yet. 884 * So check cookie length... 885 */ 886 if (SSL_IS_DTLS(s)) { 887 if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) { 888 if (CBS_len(&cookie) == 0) 889 return (1); 890 } 891 } 892 893 if (!CBS_write_bytes(&client_random, s->s3->client_random, 894 sizeof(s->s3->client_random), NULL)) 895 goto err; 896 897 s->internal->hit = 0; 898 899 /* 900 * Versions before 0.9.7 always allow clients to resume sessions in 901 * renegotiation. 0.9.7 and later allow this by default, but optionally 902 * ignore resumption requests with flag 903 * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION (it's a new flag 904 * rather than a change to default behavior so that applications 905 * relying on this for security won't even compile against older 906 * library versions). 907 * 908 * 1.0.1 and later also have a function SSL_renegotiate_abbreviated() 909 * to request renegotiation but not a new session (s->internal->new_session 910 * remains unset): for servers, this essentially just means that the 911 * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION setting will be 912 * ignored. 913 */ 914 if ((s->internal->new_session && (s->internal->options & 915 SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION))) { 916 if (!ssl_get_new_session(s, 1)) 917 goto err; 918 } else { 919 CBS ext_block; 920 921 CBS_dup(&cbs, &ext_block); 922 923 i = ssl_get_prev_session(s, &session_id, &ext_block); 924 if (i == 1) { /* previous session */ 925 s->internal->hit = 1; 926 } else if (i == -1) 927 goto err; 928 else { 929 /* i == 0 */ 930 if (!ssl_get_new_session(s, 1)) 931 goto err; 932 } 933 } 934 935 if (SSL_IS_DTLS(s)) { 936 /* 937 * The ClientHello may contain a cookie even if the HelloVerify 938 * message has not been sent - make sure that it does not cause 939 * an overflow. 940 */ 941 if (CBS_len(&cookie) > sizeof(D1I(s)->rcvd_cookie)) { 942 al = SSL_AD_DECODE_ERROR; 943 SSLerror(s, SSL_R_COOKIE_MISMATCH); 944 goto f_err; 945 } 946 947 /* Verify the cookie if appropriate option is set. */ 948 if ((SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) && 949 CBS_len(&cookie) > 0) { 950 size_t cookie_len; 951 952 /* XXX - rcvd_cookie seems to only be used here... */ 953 if (!CBS_write_bytes(&cookie, D1I(s)->rcvd_cookie, 954 sizeof(D1I(s)->rcvd_cookie), &cookie_len)) 955 goto err; 956 957 if (s->ctx->internal->app_verify_cookie_cb != NULL) { 958 if (s->ctx->internal->app_verify_cookie_cb(s, 959 D1I(s)->rcvd_cookie, cookie_len) == 0) { 960 al = SSL_AD_HANDSHAKE_FAILURE; 961 SSLerror(s, SSL_R_COOKIE_MISMATCH); 962 goto f_err; 963 } 964 /* else cookie verification succeeded */ 965 /* XXX - can d1->cookie_len > sizeof(rcvd_cookie) ? */ 966 } else if (timingsafe_memcmp(D1I(s)->rcvd_cookie, 967 D1I(s)->cookie, D1I(s)->cookie_len) != 0) { 968 /* default verification */ 969 al = SSL_AD_HANDSHAKE_FAILURE; 970 SSLerror(s, SSL_R_COOKIE_MISMATCH); 971 goto f_err; 972 } 973 cookie_valid = 1; 974 } 975 } 976 977 /* XXX - This logic seems wrong... */ 978 if (CBS_len(&cipher_suites) == 0 && CBS_len(&session_id) != 0) { 979 /* we need a cipher if we are not resuming a session */ 980 al = SSL_AD_ILLEGAL_PARAMETER; 981 SSLerror(s, SSL_R_NO_CIPHERS_SPECIFIED); 982 goto f_err; 983 } 984 985 if (CBS_len(&cipher_suites) > 0) { 986 if ((ciphers = ssl_bytes_to_cipher_list(s, 987 &cipher_suites)) == NULL) 988 goto err; 989 } 990 991 /* If it is a hit, check that the cipher is in the list */ 992 /* XXX - CBS_len(&cipher_suites) will always be zero here... */ 993 if (s->internal->hit && CBS_len(&cipher_suites) > 0) { 994 j = 0; 995 id = s->session->cipher->id; 996 997 for (i = 0; i < sk_SSL_CIPHER_num(ciphers); i++) { 998 c = sk_SSL_CIPHER_value(ciphers, i); 999 if (c->id == id) { 1000 j = 1; 1001 break; 1002 } 1003 } 1004 if (j == 0) { 1005 /* 1006 * We need to have the cipher in the cipher 1007 * list if we are asked to reuse it 1008 */ 1009 al = SSL_AD_ILLEGAL_PARAMETER; 1010 SSLerror(s, SSL_R_REQUIRED_CIPHER_MISSING); 1011 goto f_err; 1012 } 1013 } 1014 1015 comp_null = 0; 1016 while (CBS_len(&compression_methods) > 0) { 1017 if (!CBS_get_u8(&compression_methods, &comp_method)) 1018 goto truncated; 1019 if (comp_method == 0) 1020 comp_null = 1; 1021 } 1022 if (comp_null == 0) { 1023 al = SSL_AD_DECODE_ERROR; 1024 SSLerror(s, SSL_R_NO_COMPRESSION_SPECIFIED); 1025 goto f_err; 1026 } 1027 1028 if (!tlsext_server_parse(s, &cbs, &al, SSL_TLSEXT_MSG_CH)) { 1029 SSLerror(s, SSL_R_PARSE_TLSEXT); 1030 goto f_err; 1031 } 1032 1033 if (!S3I(s)->renegotiate_seen && s->internal->renegotiate) { 1034 al = SSL_AD_HANDSHAKE_FAILURE; 1035 SSLerror(s, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED); 1036 goto f_err; 1037 } 1038 1039 if (ssl_check_clienthello_tlsext_early(s) <= 0) { 1040 SSLerror(s, SSL_R_CLIENTHELLO_TLSEXT); 1041 goto err; 1042 } 1043 1044 /* 1045 * Check if we want to use external pre-shared secret for this 1046 * handshake for not reused session only. We need to generate 1047 * server_random before calling tls_session_secret_cb in order to allow 1048 * SessionTicket processing to use it in key derivation. 1049 */ 1050 arc4random_buf(s->s3->server_random, SSL3_RANDOM_SIZE); 1051 1052 if (!SSL_IS_DTLS(s) && max_version >= TLS1_2_VERSION && 1053 s->version < max_version) { 1054 /* 1055 * RFC 8446 section 4.1.3. If we are downgrading from TLS 1.3 1056 * we must set the last 8 bytes of the server random to magical 1057 * values to indicate we meant to downgrade. For TLS 1.2 it is 1058 * recommended that we do the same. 1059 */ 1060 size_t index = SSL3_RANDOM_SIZE - sizeof(tls13_downgrade_12); 1061 uint8_t *magic = &s->s3->server_random[index]; 1062 if (s->version == TLS1_2_VERSION) { 1063 /* Indicate we chose to downgrade to 1.2. */ 1064 memcpy(magic, tls13_downgrade_12, 1065 sizeof(tls13_downgrade_12)); 1066 } else { 1067 /* Indicate we chose to downgrade to 1.1 or lower */ 1068 memcpy(magic, tls13_downgrade_11, 1069 sizeof(tls13_downgrade_11)); 1070 } 1071 } 1072 1073 if (!s->internal->hit && s->internal->tls_session_secret_cb) { 1074 SSL_CIPHER *pref_cipher = NULL; 1075 1076 s->session->master_key_length = sizeof(s->session->master_key); 1077 if (s->internal->tls_session_secret_cb(s, s->session->master_key, 1078 &s->session->master_key_length, ciphers, &pref_cipher, 1079 s->internal->tls_session_secret_cb_arg)) { 1080 s->internal->hit = 1; 1081 s->session->ciphers = ciphers; 1082 s->session->verify_result = X509_V_OK; 1083 1084 ciphers = NULL; 1085 1086 /* check if some cipher was preferred by call back */ 1087 pref_cipher = pref_cipher ? pref_cipher : 1088 ssl3_choose_cipher(s, s->session->ciphers, 1089 SSL_get_ciphers(s)); 1090 if (pref_cipher == NULL) { 1091 al = SSL_AD_HANDSHAKE_FAILURE; 1092 SSLerror(s, SSL_R_NO_SHARED_CIPHER); 1093 goto f_err; 1094 } 1095 1096 s->session->cipher = pref_cipher; 1097 1098 sk_SSL_CIPHER_free(s->cipher_list); 1099 sk_SSL_CIPHER_free(s->internal->cipher_list_by_id); 1100 1101 s->cipher_list = sk_SSL_CIPHER_dup(s->session->ciphers); 1102 s->internal->cipher_list_by_id = 1103 sk_SSL_CIPHER_dup(s->session->ciphers); 1104 } 1105 } 1106 1107 /* 1108 * Given s->session->ciphers and SSL_get_ciphers, we must 1109 * pick a cipher 1110 */ 1111 1112 if (!s->internal->hit) { 1113 sk_SSL_CIPHER_free(s->session->ciphers); 1114 s->session->ciphers = ciphers; 1115 if (ciphers == NULL) { 1116 al = SSL_AD_ILLEGAL_PARAMETER; 1117 SSLerror(s, SSL_R_NO_CIPHERS_PASSED); 1118 goto f_err; 1119 } 1120 ciphers = NULL; 1121 c = ssl3_choose_cipher(s, s->session->ciphers, 1122 SSL_get_ciphers(s)); 1123 1124 if (c == NULL) { 1125 al = SSL_AD_HANDSHAKE_FAILURE; 1126 SSLerror(s, SSL_R_NO_SHARED_CIPHER); 1127 goto f_err; 1128 } 1129 S3I(s)->hs.new_cipher = c; 1130 } else { 1131 S3I(s)->hs.new_cipher = s->session->cipher; 1132 } 1133 1134 if (!tls1_transcript_hash_init(s)) 1135 goto err; 1136 1137 alg_k = S3I(s)->hs.new_cipher->algorithm_mkey; 1138 if (!(SSL_USE_SIGALGS(s) || (alg_k & SSL_kGOST)) || 1139 !(s->verify_mode & SSL_VERIFY_PEER)) 1140 tls1_transcript_free(s); 1141 1142 /* 1143 * We now have the following setup. 1144 * client_random 1145 * cipher_list - our prefered list of ciphers 1146 * ciphers - the clients prefered list of ciphers 1147 * compression - basically ignored right now 1148 * ssl version is set - sslv3 1149 * s->session - The ssl session has been setup. 1150 * s->internal->hit - session reuse flag 1151 * s->hs.new_cipher - the new cipher to use. 1152 */ 1153 1154 /* Handles TLS extensions that we couldn't check earlier */ 1155 if (ssl_check_clienthello_tlsext_late(s) <= 0) { 1156 SSLerror(s, SSL_R_CLIENTHELLO_TLSEXT); 1157 goto err; 1158 } 1159 1160 ret = cookie_valid ? 2 : 1; 1161 1162 if (0) { 1163 truncated: 1164 al = SSL_AD_DECODE_ERROR; 1165 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 1166 f_err: 1167 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1168 } 1169 err: 1170 sk_SSL_CIPHER_free(ciphers); 1171 1172 return (ret); 1173 } 1174 1175 int 1176 ssl3_send_server_hello(SSL *s) 1177 { 1178 CBB cbb, server_hello, session_id; 1179 size_t sl; 1180 1181 memset(&cbb, 0, sizeof(cbb)); 1182 1183 if (S3I(s)->hs.state == SSL3_ST_SW_SRVR_HELLO_A) { 1184 if (!ssl3_handshake_msg_start(s, &cbb, &server_hello, 1185 SSL3_MT_SERVER_HELLO)) 1186 goto err; 1187 1188 if (!CBB_add_u16(&server_hello, s->version)) 1189 goto err; 1190 if (!CBB_add_bytes(&server_hello, s->s3->server_random, 1191 sizeof(s->s3->server_random))) 1192 goto err; 1193 1194 /* 1195 * There are several cases for the session ID to send 1196 * back in the server hello: 1197 * 1198 * - For session reuse from the session cache, 1199 * we send back the old session ID. 1200 * - If stateless session reuse (using a session ticket) 1201 * is successful, we send back the client's "session ID" 1202 * (which doesn't actually identify the session). 1203 * - If it is a new session, we send back the new 1204 * session ID. 1205 * - However, if we want the new session to be single-use, 1206 * we send back a 0-length session ID. 1207 * 1208 * s->internal->hit is non-zero in either case of session reuse, 1209 * so the following won't overwrite an ID that we're supposed 1210 * to send back. 1211 */ 1212 if (!(s->ctx->internal->session_cache_mode & SSL_SESS_CACHE_SERVER) 1213 && !s->internal->hit) 1214 s->session->session_id_length = 0; 1215 1216 sl = s->session->session_id_length; 1217 if (sl > sizeof(s->session->session_id)) { 1218 SSLerror(s, ERR_R_INTERNAL_ERROR); 1219 goto err; 1220 } 1221 if (!CBB_add_u8_length_prefixed(&server_hello, &session_id)) 1222 goto err; 1223 if (!CBB_add_bytes(&session_id, s->session->session_id, sl)) 1224 goto err; 1225 1226 /* Cipher suite. */ 1227 if (!CBB_add_u16(&server_hello, 1228 ssl3_cipher_get_value(S3I(s)->hs.new_cipher))) 1229 goto err; 1230 1231 /* Compression method (null). */ 1232 if (!CBB_add_u8(&server_hello, 0)) 1233 goto err; 1234 1235 /* TLS extensions */ 1236 if (!tlsext_server_build(s, &server_hello, SSL_TLSEXT_MSG_SH)) { 1237 SSLerror(s, ERR_R_INTERNAL_ERROR); 1238 goto err; 1239 } 1240 1241 if (!ssl3_handshake_msg_finish(s, &cbb)) 1242 goto err; 1243 } 1244 1245 /* SSL3_ST_SW_SRVR_HELLO_B */ 1246 return (ssl3_handshake_write(s)); 1247 1248 err: 1249 CBB_cleanup(&cbb); 1250 1251 return (-1); 1252 } 1253 1254 int 1255 ssl3_send_server_done(SSL *s) 1256 { 1257 CBB cbb, done; 1258 1259 memset(&cbb, 0, sizeof(cbb)); 1260 1261 if (S3I(s)->hs.state == SSL3_ST_SW_SRVR_DONE_A) { 1262 if (!ssl3_handshake_msg_start(s, &cbb, &done, 1263 SSL3_MT_SERVER_DONE)) 1264 goto err; 1265 if (!ssl3_handshake_msg_finish(s, &cbb)) 1266 goto err; 1267 1268 S3I(s)->hs.state = SSL3_ST_SW_SRVR_DONE_B; 1269 } 1270 1271 /* SSL3_ST_SW_SRVR_DONE_B */ 1272 return (ssl3_handshake_write(s)); 1273 1274 err: 1275 CBB_cleanup(&cbb); 1276 1277 return (-1); 1278 } 1279 1280 static int 1281 ssl3_send_server_kex_dhe(SSL *s, CBB *cbb) 1282 { 1283 CBB dh_p, dh_g, dh_Ys; 1284 DH *dh = NULL, *dhp; 1285 unsigned char *data; 1286 int al; 1287 1288 if (s->cert->dh_tmp_auto != 0) { 1289 if ((dhp = ssl_get_auto_dh(s)) == NULL) { 1290 al = SSL_AD_INTERNAL_ERROR; 1291 SSLerror(s, ERR_R_INTERNAL_ERROR); 1292 goto f_err; 1293 } 1294 } else 1295 dhp = s->cert->dh_tmp; 1296 1297 if (dhp == NULL && s->cert->dh_tmp_cb != NULL) 1298 dhp = s->cert->dh_tmp_cb(s, 0, 1299 SSL_C_PKEYLENGTH(S3I(s)->hs.new_cipher)); 1300 1301 if (dhp == NULL) { 1302 al = SSL_AD_HANDSHAKE_FAILURE; 1303 SSLerror(s, SSL_R_MISSING_TMP_DH_KEY); 1304 goto f_err; 1305 } 1306 1307 if (S3I(s)->tmp.dh != NULL) { 1308 SSLerror(s, ERR_R_INTERNAL_ERROR); 1309 goto err; 1310 } 1311 1312 if (s->cert->dh_tmp_auto != 0) { 1313 dh = dhp; 1314 } else if ((dh = DHparams_dup(dhp)) == NULL) { 1315 SSLerror(s, ERR_R_DH_LIB); 1316 goto err; 1317 } 1318 S3I(s)->tmp.dh = dh; 1319 if (!DH_generate_key(dh)) { 1320 SSLerror(s, ERR_R_DH_LIB); 1321 goto err; 1322 } 1323 1324 /* 1325 * Serialize the DH parameters and public key. 1326 */ 1327 if (!CBB_add_u16_length_prefixed(cbb, &dh_p)) 1328 goto err; 1329 if (!CBB_add_space(&dh_p, &data, BN_num_bytes(dh->p))) 1330 goto err; 1331 BN_bn2bin(dh->p, data); 1332 1333 if (!CBB_add_u16_length_prefixed(cbb, &dh_g)) 1334 goto err; 1335 if (!CBB_add_space(&dh_g, &data, BN_num_bytes(dh->g))) 1336 goto err; 1337 BN_bn2bin(dh->g, data); 1338 1339 if (!CBB_add_u16_length_prefixed(cbb, &dh_Ys)) 1340 goto err; 1341 if (!CBB_add_space(&dh_Ys, &data, BN_num_bytes(dh->pub_key))) 1342 goto err; 1343 BN_bn2bin(dh->pub_key, data); 1344 1345 if (!CBB_flush(cbb)) 1346 goto err; 1347 1348 return (1); 1349 1350 f_err: 1351 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1352 err: 1353 return (-1); 1354 } 1355 1356 static int 1357 ssl3_send_server_kex_ecdhe_ecp(SSL *s, int nid, CBB *cbb) 1358 { 1359 int curve_id = 0; 1360 EC_KEY *ecdh; 1361 CBB ecpoint; 1362 int al; 1363 1364 /* 1365 * Only named curves are supported in ECDH ephemeral key exchanges. 1366 * For supported named curves, curve_id is non-zero. 1367 */ 1368 if ((curve_id = tls1_ec_nid2curve_id(nid)) == 0) { 1369 SSLerror(s, SSL_R_UNSUPPORTED_ELLIPTIC_CURVE); 1370 goto err; 1371 } 1372 1373 if (S3I(s)->tmp.ecdh != NULL) { 1374 SSLerror(s, ERR_R_INTERNAL_ERROR); 1375 goto err; 1376 } 1377 1378 if ((S3I(s)->tmp.ecdh = EC_KEY_new()) == NULL) { 1379 al = SSL_AD_HANDSHAKE_FAILURE; 1380 SSLerror(s, SSL_R_MISSING_TMP_ECDH_KEY); 1381 goto f_err; 1382 } 1383 S3I(s)->tmp.ecdh_nid = nid; 1384 ecdh = S3I(s)->tmp.ecdh; 1385 1386 if (!ssl_kex_generate_ecdhe_ecp(ecdh, nid)) 1387 goto err; 1388 1389 /* 1390 * Encode the public key. 1391 * 1392 * Only named curves are supported in ECDH ephemeral key exchanges. 1393 * In this case the ServerKeyExchange message has: 1394 * [1 byte CurveType], [2 byte CurveName] 1395 * [1 byte length of encoded point], followed by 1396 * the actual encoded point itself. 1397 */ 1398 if (!CBB_add_u8(cbb, NAMED_CURVE_TYPE)) 1399 goto err; 1400 if (!CBB_add_u16(cbb, curve_id)) 1401 goto err; 1402 if (!CBB_add_u8_length_prefixed(cbb, &ecpoint)) 1403 goto err; 1404 if (!ssl_kex_public_ecdhe_ecp(ecdh, &ecpoint)) 1405 goto err; 1406 if (!CBB_flush(cbb)) 1407 goto err; 1408 1409 return (1); 1410 1411 f_err: 1412 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1413 err: 1414 return (-1); 1415 } 1416 1417 static int 1418 ssl3_send_server_kex_ecdhe_ecx(SSL *s, int nid, CBB *cbb) 1419 { 1420 uint8_t *public_key = NULL, *private_key = NULL; 1421 int curve_id; 1422 CBB ecpoint; 1423 int ret = -1; 1424 1425 /* Generate an X25519 key pair. */ 1426 if (S3I(s)->tmp.x25519 != NULL) { 1427 SSLerror(s, ERR_R_INTERNAL_ERROR); 1428 goto err; 1429 } 1430 if ((private_key = malloc(X25519_KEY_LENGTH)) == NULL) 1431 goto err; 1432 if ((public_key = malloc(X25519_KEY_LENGTH)) == NULL) 1433 goto err; 1434 X25519_keypair(public_key, private_key); 1435 1436 /* Serialize public key. */ 1437 if ((curve_id = tls1_ec_nid2curve_id(nid)) == 0) { 1438 SSLerror(s, SSL_R_UNSUPPORTED_ELLIPTIC_CURVE); 1439 goto err; 1440 } 1441 1442 if (!CBB_add_u8(cbb, NAMED_CURVE_TYPE)) 1443 goto err; 1444 if (!CBB_add_u16(cbb, curve_id)) 1445 goto err; 1446 if (!CBB_add_u8_length_prefixed(cbb, &ecpoint)) 1447 goto err; 1448 if (!CBB_add_bytes(&ecpoint, public_key, X25519_KEY_LENGTH)) 1449 goto err; 1450 if (!CBB_flush(cbb)) 1451 goto err; 1452 1453 S3I(s)->tmp.x25519 = private_key; 1454 private_key = NULL; 1455 ret = 1; 1456 1457 err: 1458 free(public_key); 1459 freezero(private_key, X25519_KEY_LENGTH); 1460 1461 return (ret); 1462 } 1463 1464 static int 1465 ssl3_send_server_kex_ecdhe(SSL *s, CBB *cbb) 1466 { 1467 int nid; 1468 1469 nid = tls1_get_shared_curve(s); 1470 1471 if (nid == NID_X25519) 1472 return ssl3_send_server_kex_ecdhe_ecx(s, nid, cbb); 1473 1474 return ssl3_send_server_kex_ecdhe_ecp(s, nid, cbb); 1475 } 1476 1477 int 1478 ssl3_send_server_key_exchange(SSL *s) 1479 { 1480 CBB cbb, cbb_params, cbb_signature, server_kex; 1481 const struct ssl_sigalg *sigalg = NULL; 1482 unsigned char *signature = NULL; 1483 size_t signature_len = 0; 1484 unsigned char *params = NULL; 1485 size_t params_len; 1486 const EVP_MD *md = NULL; 1487 unsigned long type; 1488 EVP_MD_CTX md_ctx; 1489 EVP_PKEY_CTX *pctx; 1490 EVP_PKEY *pkey; 1491 int al; 1492 1493 memset(&cbb, 0, sizeof(cbb)); 1494 memset(&cbb_params, 0, sizeof(cbb_params)); 1495 1496 EVP_MD_CTX_init(&md_ctx); 1497 1498 if (S3I(s)->hs.state == SSL3_ST_SW_KEY_EXCH_A) { 1499 1500 if (!ssl3_handshake_msg_start(s, &cbb, &server_kex, 1501 SSL3_MT_SERVER_KEY_EXCHANGE)) 1502 goto err; 1503 1504 if (!CBB_init(&cbb_params, 0)) 1505 goto err; 1506 1507 type = S3I(s)->hs.new_cipher->algorithm_mkey; 1508 if (type & SSL_kDHE) { 1509 if (ssl3_send_server_kex_dhe(s, &cbb_params) != 1) 1510 goto err; 1511 } else if (type & SSL_kECDHE) { 1512 if (ssl3_send_server_kex_ecdhe(s, &cbb_params) != 1) 1513 goto err; 1514 } else { 1515 al = SSL_AD_HANDSHAKE_FAILURE; 1516 SSLerror(s, SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE); 1517 goto f_err; 1518 } 1519 1520 if (!CBB_finish(&cbb_params, ¶ms, ¶ms_len)) 1521 goto err; 1522 1523 if (!CBB_add_bytes(&server_kex, params, params_len)) 1524 goto err; 1525 1526 /* Add signature unless anonymous. */ 1527 if (!(S3I(s)->hs.new_cipher->algorithm_auth & SSL_aNULL)) { 1528 if ((pkey = ssl_get_sign_pkey(s, S3I(s)->hs.new_cipher, 1529 &md, &sigalg)) == NULL) { 1530 al = SSL_AD_DECODE_ERROR; 1531 goto f_err; 1532 } 1533 1534 /* Send signature algorithm. */ 1535 if (SSL_USE_SIGALGS(s)) { 1536 if (!CBB_add_u16(&server_kex, sigalg->value)) { 1537 al = SSL_AD_INTERNAL_ERROR; 1538 SSLerror(s, ERR_R_INTERNAL_ERROR); 1539 goto f_err; 1540 } 1541 } 1542 1543 if (!EVP_DigestSignInit(&md_ctx, &pctx, md, NULL, pkey)) { 1544 SSLerror(s, ERR_R_EVP_LIB); 1545 goto err; 1546 } 1547 if ((sigalg->flags & SIGALG_FLAG_RSA_PSS) && 1548 (!EVP_PKEY_CTX_set_rsa_padding(pctx, 1549 RSA_PKCS1_PSS_PADDING) || 1550 !EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, -1))) { 1551 SSLerror(s, ERR_R_EVP_LIB); 1552 goto err; 1553 } 1554 if (!EVP_DigestSignUpdate(&md_ctx, s->s3->client_random, 1555 SSL3_RANDOM_SIZE)) { 1556 SSLerror(s, ERR_R_EVP_LIB); 1557 goto err; 1558 } 1559 if (!EVP_DigestSignUpdate(&md_ctx, s->s3->server_random, 1560 SSL3_RANDOM_SIZE)) { 1561 SSLerror(s, ERR_R_EVP_LIB); 1562 goto err; 1563 } 1564 if (!EVP_DigestSignUpdate(&md_ctx, params, params_len)) { 1565 SSLerror(s, ERR_R_EVP_LIB); 1566 goto err; 1567 } 1568 if (!EVP_DigestSignFinal(&md_ctx, NULL, &signature_len) || 1569 !signature_len) { 1570 SSLerror(s, ERR_R_EVP_LIB); 1571 goto err; 1572 } 1573 if ((signature = calloc(1, signature_len)) == NULL) { 1574 SSLerror(s, ERR_R_MALLOC_FAILURE); 1575 goto err; 1576 } 1577 if (!EVP_DigestSignFinal(&md_ctx, signature, &signature_len)) { 1578 SSLerror(s, ERR_R_EVP_LIB); 1579 goto err; 1580 } 1581 1582 if (!CBB_add_u16_length_prefixed(&server_kex, 1583 &cbb_signature)) 1584 goto err; 1585 if (!CBB_add_bytes(&cbb_signature, signature, 1586 signature_len)) 1587 goto err; 1588 } 1589 1590 if (!ssl3_handshake_msg_finish(s, &cbb)) 1591 goto err; 1592 1593 S3I(s)->hs.state = SSL3_ST_SW_KEY_EXCH_B; 1594 } 1595 1596 EVP_MD_CTX_cleanup(&md_ctx); 1597 free(params); 1598 free(signature); 1599 1600 return (ssl3_handshake_write(s)); 1601 1602 f_err: 1603 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1604 err: 1605 CBB_cleanup(&cbb_params); 1606 CBB_cleanup(&cbb); 1607 EVP_MD_CTX_cleanup(&md_ctx); 1608 free(params); 1609 free(signature); 1610 1611 return (-1); 1612 } 1613 1614 int 1615 ssl3_send_certificate_request(SSL *s) 1616 { 1617 CBB cbb, cert_request, cert_types, sigalgs, cert_auth, dn; 1618 STACK_OF(X509_NAME) *sk = NULL; 1619 X509_NAME *name; 1620 int i; 1621 1622 /* 1623 * Certificate Request - RFC 5246 section 7.4.4. 1624 */ 1625 1626 memset(&cbb, 0, sizeof(cbb)); 1627 1628 if (S3I(s)->hs.state == SSL3_ST_SW_CERT_REQ_A) { 1629 if (!ssl3_handshake_msg_start(s, &cbb, &cert_request, 1630 SSL3_MT_CERTIFICATE_REQUEST)) 1631 goto err; 1632 1633 if (!CBB_add_u8_length_prefixed(&cert_request, &cert_types)) 1634 goto err; 1635 if (!ssl3_get_req_cert_types(s, &cert_types)) 1636 goto err; 1637 1638 if (SSL_USE_SIGALGS(s)) { 1639 if (!CBB_add_u16_length_prefixed(&cert_request, &sigalgs)) 1640 goto err; 1641 if (!ssl_sigalgs_build(&sigalgs, tls12_sigalgs, tls12_sigalgs_len)) 1642 goto err; 1643 } 1644 1645 if (!CBB_add_u16_length_prefixed(&cert_request, &cert_auth)) 1646 goto err; 1647 1648 sk = SSL_get_client_CA_list(s); 1649 for (i = 0; i < sk_X509_NAME_num(sk); i++) { 1650 unsigned char *name_data; 1651 size_t name_len; 1652 1653 name = sk_X509_NAME_value(sk, i); 1654 name_len = i2d_X509_NAME(name, NULL); 1655 1656 if (!CBB_add_u16_length_prefixed(&cert_auth, &dn)) 1657 goto err; 1658 if (!CBB_add_space(&dn, &name_data, name_len)) 1659 goto err; 1660 if (i2d_X509_NAME(name, &name_data) != name_len) 1661 goto err; 1662 } 1663 1664 if (!ssl3_handshake_msg_finish(s, &cbb)) 1665 goto err; 1666 1667 S3I(s)->hs.state = SSL3_ST_SW_CERT_REQ_B; 1668 } 1669 1670 /* SSL3_ST_SW_CERT_REQ_B */ 1671 return (ssl3_handshake_write(s)); 1672 1673 err: 1674 CBB_cleanup(&cbb); 1675 1676 return (-1); 1677 } 1678 1679 static int 1680 ssl3_get_client_kex_rsa(SSL *s, CBS *cbs) 1681 { 1682 unsigned char fakekey[SSL_MAX_MASTER_KEY_LENGTH]; 1683 unsigned char *pms = NULL; 1684 unsigned char *p; 1685 size_t pms_len = 0; 1686 EVP_PKEY *pkey = NULL; 1687 RSA *rsa = NULL; 1688 CBS enc_pms; 1689 int decrypt_len; 1690 int al = -1; 1691 1692 arc4random_buf(fakekey, sizeof(fakekey)); 1693 fakekey[0] = s->client_version >> 8; 1694 fakekey[1] = s->client_version & 0xff; 1695 1696 pkey = s->cert->pkeys[SSL_PKEY_RSA].privatekey; 1697 if ((pkey == NULL) || (pkey->type != EVP_PKEY_RSA) || 1698 (pkey->pkey.rsa == NULL)) { 1699 al = SSL_AD_HANDSHAKE_FAILURE; 1700 SSLerror(s, SSL_R_MISSING_RSA_CERTIFICATE); 1701 goto f_err; 1702 } 1703 rsa = pkey->pkey.rsa; 1704 1705 pms_len = RSA_size(rsa); 1706 if (pms_len < SSL_MAX_MASTER_KEY_LENGTH) 1707 goto err; 1708 if ((pms = malloc(pms_len)) == NULL) 1709 goto err; 1710 p = pms; 1711 1712 if (!CBS_get_u16_length_prefixed(cbs, &enc_pms)) 1713 goto truncated; 1714 if (CBS_len(cbs) != 0 || CBS_len(&enc_pms) != RSA_size(rsa)) { 1715 SSLerror(s, SSL_R_TLS_RSA_ENCRYPTED_VALUE_LENGTH_IS_WRONG); 1716 goto err; 1717 } 1718 1719 decrypt_len = RSA_private_decrypt(CBS_len(&enc_pms), CBS_data(&enc_pms), 1720 pms, rsa, RSA_PKCS1_PADDING); 1721 1722 ERR_clear_error(); 1723 1724 if (decrypt_len != SSL_MAX_MASTER_KEY_LENGTH) { 1725 al = SSL_AD_DECODE_ERROR; 1726 /* SSLerror(s, SSL_R_BAD_RSA_DECRYPT); */ 1727 } 1728 1729 if ((al == -1) && !((pms[0] == (s->client_version >> 8)) && 1730 (pms[1] == (s->client_version & 0xff)))) { 1731 /* 1732 * The premaster secret must contain the same version number 1733 * as the ClientHello to detect version rollback attacks 1734 * (strangely, the protocol does not offer such protection for 1735 * DH ciphersuites). 1736 * 1737 * The Klima-Pokorny-Rosa extension of Bleichenbacher's attack 1738 * (http://eprint.iacr.org/2003/052/) exploits the version 1739 * number check as a "bad version oracle" -- an alert would 1740 * reveal that the plaintext corresponding to some ciphertext 1741 * made up by the adversary is properly formatted except that 1742 * the version number is wrong. To avoid such attacks, we should 1743 * treat this just like any other decryption error. 1744 */ 1745 al = SSL_AD_DECODE_ERROR; 1746 /* SSLerror(s, SSL_R_BAD_PROTOCOL_VERSION_NUMBER); */ 1747 } 1748 1749 if (al != -1) { 1750 /* 1751 * Some decryption failure -- use random value instead 1752 * as countermeasure against Bleichenbacher's attack 1753 * on PKCS #1 v1.5 RSA padding (see RFC 2246, 1754 * section 7.4.7.1). 1755 */ 1756 p = fakekey; 1757 } 1758 1759 s->session->master_key_length = 1760 tls1_generate_master_secret(s, 1761 s->session->master_key, p, SSL_MAX_MASTER_KEY_LENGTH); 1762 1763 freezero(pms, pms_len); 1764 1765 return (1); 1766 1767 truncated: 1768 al = SSL_AD_DECODE_ERROR; 1769 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 1770 f_err: 1771 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1772 err: 1773 freezero(pms, pms_len); 1774 1775 return (-1); 1776 } 1777 1778 static int 1779 ssl3_get_client_kex_dhe(SSL *s, CBS *cbs) 1780 { 1781 int key_size = 0; 1782 int key_is_invalid, key_len, al; 1783 unsigned char *key = NULL; 1784 BIGNUM *bn = NULL; 1785 CBS dh_Yc; 1786 DH *dh; 1787 1788 if (!CBS_get_u16_length_prefixed(cbs, &dh_Yc)) 1789 goto truncated; 1790 if (CBS_len(cbs) != 0) 1791 goto truncated; 1792 1793 if (S3I(s)->tmp.dh == NULL) { 1794 al = SSL_AD_HANDSHAKE_FAILURE; 1795 SSLerror(s, SSL_R_MISSING_TMP_DH_KEY); 1796 goto f_err; 1797 } 1798 dh = S3I(s)->tmp.dh; 1799 1800 if ((bn = BN_bin2bn(CBS_data(&dh_Yc), CBS_len(&dh_Yc), NULL)) == NULL) { 1801 SSLerror(s, SSL_R_BN_LIB); 1802 goto err; 1803 } 1804 1805 if ((key_size = DH_size(dh)) <= 0) { 1806 SSLerror(s, ERR_R_DH_LIB); 1807 goto err; 1808 } 1809 if ((key = malloc(key_size)) == NULL) { 1810 SSLerror(s, ERR_R_MALLOC_FAILURE); 1811 goto err; 1812 } 1813 if (!DH_check_pub_key(dh, bn, &key_is_invalid)) { 1814 al = SSL_AD_INTERNAL_ERROR; 1815 SSLerror(s, ERR_R_DH_LIB); 1816 goto f_err; 1817 } 1818 if (key_is_invalid) { 1819 al = SSL_AD_ILLEGAL_PARAMETER; 1820 SSLerror(s, ERR_R_DH_LIB); 1821 goto f_err; 1822 } 1823 if ((key_len = DH_compute_key(key, bn, dh)) <= 0) { 1824 al = SSL_AD_INTERNAL_ERROR; 1825 SSLerror(s, ERR_R_DH_LIB); 1826 goto f_err; 1827 } 1828 1829 s->session->master_key_length = tls1_generate_master_secret(s, 1830 s->session->master_key, key, key_len); 1831 1832 DH_free(S3I(s)->tmp.dh); 1833 S3I(s)->tmp.dh = NULL; 1834 1835 freezero(key, key_size); 1836 BN_clear_free(bn); 1837 1838 return (1); 1839 1840 truncated: 1841 al = SSL_AD_DECODE_ERROR; 1842 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 1843 f_err: 1844 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1845 err: 1846 freezero(key, key_size); 1847 BN_clear_free(bn); 1848 1849 return (-1); 1850 } 1851 1852 static int 1853 ssl3_get_client_kex_ecdhe_ecp(SSL *s, CBS *cbs) 1854 { 1855 uint8_t *key = NULL; 1856 size_t key_len = 0; 1857 EC_KEY *ecdh_peer = NULL; 1858 EC_KEY *ecdh; 1859 CBS public; 1860 int ret = -1; 1861 1862 /* 1863 * Use the ephemeral values we saved when generating the 1864 * ServerKeyExchange message. 1865 */ 1866 if ((ecdh = S3I(s)->tmp.ecdh) == NULL) { 1867 SSLerror(s, ERR_R_INTERNAL_ERROR); 1868 goto err; 1869 } 1870 1871 /* 1872 * Get client's public key from encoded point in the ClientKeyExchange 1873 * message. 1874 */ 1875 if (!CBS_get_u8_length_prefixed(cbs, &public)) 1876 goto err; 1877 if (CBS_len(cbs) != 0) 1878 goto err; 1879 1880 if ((ecdh_peer = EC_KEY_new()) == NULL) 1881 goto err; 1882 1883 if (!ssl_kex_peer_public_ecdhe_ecp(ecdh_peer, S3I(s)->tmp.ecdh_nid, 1884 &public)) 1885 goto err; 1886 1887 /* Derive the shared secret and compute master secret. */ 1888 if (!ssl_kex_derive_ecdhe_ecp(ecdh, ecdh_peer, &key, &key_len)) 1889 goto err; 1890 s->session->master_key_length = tls1_generate_master_secret(s, 1891 s->session->master_key, key, key_len); 1892 1893 EC_KEY_free(S3I(s)->tmp.ecdh); 1894 S3I(s)->tmp.ecdh = NULL; 1895 S3I(s)->tmp.ecdh_nid = NID_undef; 1896 1897 ret = 1; 1898 1899 err: 1900 freezero(key, key_len); 1901 EC_KEY_free(ecdh_peer); 1902 1903 return (ret); 1904 } 1905 1906 static int 1907 ssl3_get_client_kex_ecdhe_ecx(SSL *s, CBS *cbs) 1908 { 1909 uint8_t *shared_key = NULL; 1910 CBS ecpoint; 1911 int ret = -1; 1912 1913 if (!CBS_get_u8_length_prefixed(cbs, &ecpoint)) 1914 goto err; 1915 if (CBS_len(cbs) != 0) 1916 goto err; 1917 if (CBS_len(&ecpoint) != X25519_KEY_LENGTH) 1918 goto err; 1919 1920 if ((shared_key = malloc(X25519_KEY_LENGTH)) == NULL) 1921 goto err; 1922 if (!X25519(shared_key, S3I(s)->tmp.x25519, CBS_data(&ecpoint))) 1923 goto err; 1924 1925 freezero(S3I(s)->tmp.x25519, X25519_KEY_LENGTH); 1926 S3I(s)->tmp.x25519 = NULL; 1927 1928 s->session->master_key_length = 1929 tls1_generate_master_secret( 1930 s, s->session->master_key, shared_key, X25519_KEY_LENGTH); 1931 1932 ret = 1; 1933 1934 err: 1935 freezero(shared_key, X25519_KEY_LENGTH); 1936 1937 return (ret); 1938 } 1939 1940 static int 1941 ssl3_get_client_kex_ecdhe(SSL *s, CBS *cbs) 1942 { 1943 if (S3I(s)->tmp.x25519 != NULL) 1944 return ssl3_get_client_kex_ecdhe_ecx(s, cbs); 1945 1946 return ssl3_get_client_kex_ecdhe_ecp(s, cbs); 1947 } 1948 1949 static int 1950 ssl3_get_client_kex_gost(SSL *s, CBS *cbs) 1951 { 1952 EVP_PKEY_CTX *pkey_ctx; 1953 EVP_PKEY *client_pub_pkey = NULL, *pk = NULL; 1954 unsigned char premaster_secret[32]; 1955 unsigned long alg_a; 1956 size_t outlen = 32; 1957 CBS gostblob; 1958 int al; 1959 int ret = 0; 1960 1961 /* Get our certificate private key*/ 1962 alg_a = S3I(s)->hs.new_cipher->algorithm_auth; 1963 if (alg_a & SSL_aGOST01) 1964 pk = s->cert->pkeys[SSL_PKEY_GOST01].privatekey; 1965 1966 if ((pkey_ctx = EVP_PKEY_CTX_new(pk, NULL)) == NULL) 1967 goto err; 1968 if (EVP_PKEY_decrypt_init(pkey_ctx) <= 0) 1969 goto gerr; 1970 1971 /* 1972 * If client certificate is present and is of the same type, 1973 * maybe use it for key exchange. 1974 * Don't mind errors from EVP_PKEY_derive_set_peer, because 1975 * it is completely valid to use a client certificate for 1976 * authorization only. 1977 */ 1978 if ((client_pub_pkey = X509_get_pubkey(s->session->peer)) != NULL) { 1979 if (EVP_PKEY_derive_set_peer(pkey_ctx, 1980 client_pub_pkey) <= 0) 1981 ERR_clear_error(); 1982 } 1983 1984 /* Decrypt session key */ 1985 if (!CBS_get_asn1(cbs, &gostblob, CBS_ASN1_SEQUENCE)) 1986 goto truncated; 1987 if (CBS_len(cbs) != 0) 1988 goto truncated; 1989 if (EVP_PKEY_decrypt(pkey_ctx, premaster_secret, &outlen, 1990 CBS_data(&gostblob), CBS_len(&gostblob)) <= 0) { 1991 SSLerror(s, SSL_R_DECRYPTION_FAILED); 1992 goto gerr; 1993 } 1994 1995 /* Generate master secret */ 1996 s->session->master_key_length = 1997 tls1_generate_master_secret( 1998 s, s->session->master_key, premaster_secret, 32); 1999 2000 /* Check if pubkey from client certificate was used */ 2001 if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, -1, 2002 EVP_PKEY_CTRL_PEER_KEY, 2, NULL) > 0) 2003 ret = 2; 2004 else 2005 ret = 1; 2006 gerr: 2007 EVP_PKEY_free(client_pub_pkey); 2008 EVP_PKEY_CTX_free(pkey_ctx); 2009 if (ret) 2010 return (ret); 2011 else 2012 goto err; 2013 2014 truncated: 2015 al = SSL_AD_DECODE_ERROR; 2016 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 2017 ssl3_send_alert(s, SSL3_AL_FATAL, al); 2018 err: 2019 return (-1); 2020 } 2021 2022 int 2023 ssl3_get_client_key_exchange(SSL *s) 2024 { 2025 unsigned long alg_k; 2026 int al, ok; 2027 CBS cbs; 2028 long n; 2029 2030 /* 2048 maxlen is a guess. How long a key does that permit? */ 2031 n = ssl3_get_message(s, SSL3_ST_SR_KEY_EXCH_A, 2032 SSL3_ST_SR_KEY_EXCH_B, SSL3_MT_CLIENT_KEY_EXCHANGE, 2048, &ok); 2033 if (!ok) 2034 return ((int)n); 2035 2036 if (n < 0) 2037 goto err; 2038 2039 CBS_init(&cbs, s->internal->init_msg, n); 2040 2041 alg_k = S3I(s)->hs.new_cipher->algorithm_mkey; 2042 2043 if (alg_k & SSL_kRSA) { 2044 if (ssl3_get_client_kex_rsa(s, &cbs) != 1) 2045 goto err; 2046 } else if (alg_k & SSL_kDHE) { 2047 if (ssl3_get_client_kex_dhe(s, &cbs) != 1) 2048 goto err; 2049 } else if (alg_k & SSL_kECDHE) { 2050 if (ssl3_get_client_kex_ecdhe(s, &cbs) != 1) 2051 goto err; 2052 } else if (alg_k & SSL_kGOST) { 2053 if (ssl3_get_client_kex_gost(s, &cbs) != 1) 2054 goto err; 2055 } else { 2056 al = SSL_AD_HANDSHAKE_FAILURE; 2057 SSLerror(s, SSL_R_UNKNOWN_CIPHER_TYPE); 2058 goto f_err; 2059 } 2060 2061 if (CBS_len(&cbs) != 0) { 2062 al = SSL_AD_DECODE_ERROR; 2063 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 2064 goto f_err; 2065 } 2066 2067 return (1); 2068 2069 f_err: 2070 ssl3_send_alert(s, SSL3_AL_FATAL, al); 2071 err: 2072 return (-1); 2073 } 2074 2075 int 2076 ssl3_get_cert_verify(SSL *s) 2077 { 2078 CBS cbs, signature; 2079 const struct ssl_sigalg *sigalg = NULL; 2080 const EVP_MD *md = NULL; 2081 EVP_PKEY *pkey = NULL; 2082 X509 *peer = NULL; 2083 EVP_MD_CTX mctx; 2084 int al, ok, verify; 2085 const unsigned char *hdata; 2086 size_t hdatalen; 2087 int type = 0; 2088 int ret = 0; 2089 long n; 2090 2091 EVP_MD_CTX_init(&mctx); 2092 2093 n = ssl3_get_message(s, SSL3_ST_SR_CERT_VRFY_A, 2094 SSL3_ST_SR_CERT_VRFY_B, -1, SSL3_RT_MAX_PLAIN_LENGTH, &ok); 2095 if (!ok) 2096 return ((int)n); 2097 2098 if (n < 0) 2099 goto err; 2100 2101 CBS_init(&cbs, s->internal->init_msg, n); 2102 2103 if (s->session->peer != NULL) { 2104 peer = s->session->peer; 2105 pkey = X509_get_pubkey(peer); 2106 type = X509_certificate_type(peer, pkey); 2107 } 2108 2109 if (S3I(s)->tmp.message_type != SSL3_MT_CERTIFICATE_VERIFY) { 2110 S3I(s)->tmp.reuse_message = 1; 2111 if (peer != NULL) { 2112 al = SSL_AD_UNEXPECTED_MESSAGE; 2113 SSLerror(s, SSL_R_MISSING_VERIFY_MESSAGE); 2114 goto f_err; 2115 } 2116 ret = 1; 2117 goto end; 2118 } 2119 2120 if (peer == NULL) { 2121 SSLerror(s, SSL_R_NO_CLIENT_CERT_RECEIVED); 2122 al = SSL_AD_UNEXPECTED_MESSAGE; 2123 goto f_err; 2124 } 2125 2126 if (!(type & EVP_PKT_SIGN)) { 2127 SSLerror(s, SSL_R_SIGNATURE_FOR_NON_SIGNING_CERTIFICATE); 2128 al = SSL_AD_ILLEGAL_PARAMETER; 2129 goto f_err; 2130 } 2131 2132 if (S3I(s)->change_cipher_spec) { 2133 SSLerror(s, SSL_R_CCS_RECEIVED_EARLY); 2134 al = SSL_AD_UNEXPECTED_MESSAGE; 2135 goto f_err; 2136 } 2137 2138 if (!SSL_USE_SIGALGS(s)) { 2139 if (!CBS_get_u16_length_prefixed(&cbs, &signature)) 2140 goto err; 2141 if (CBS_len(&signature) > EVP_PKEY_size(pkey)) { 2142 SSLerror(s, SSL_R_WRONG_SIGNATURE_SIZE); 2143 al = SSL_AD_DECODE_ERROR; 2144 goto f_err; 2145 } 2146 if (CBS_len(&cbs) != 0) { 2147 al = SSL_AD_DECODE_ERROR; 2148 SSLerror(s, SSL_R_EXTRA_DATA_IN_MESSAGE); 2149 goto f_err; 2150 } 2151 } 2152 2153 if (SSL_USE_SIGALGS(s)) { 2154 EVP_PKEY_CTX *pctx; 2155 uint16_t sigalg_value; 2156 2157 if (!CBS_get_u16(&cbs, &sigalg_value)) 2158 goto truncated; 2159 if ((sigalg = ssl_sigalg(sigalg_value, tls12_sigalgs, 2160 tls12_sigalgs_len)) == NULL || 2161 (md = sigalg->md()) == NULL) { 2162 SSLerror(s, SSL_R_UNKNOWN_DIGEST); 2163 al = SSL_AD_DECODE_ERROR; 2164 goto f_err; 2165 } 2166 if (!ssl_sigalg_pkey_ok(sigalg, pkey, 0)) { 2167 SSLerror(s, SSL_R_WRONG_SIGNATURE_TYPE); 2168 al = SSL_AD_DECODE_ERROR; 2169 goto f_err; 2170 } 2171 2172 if (!CBS_get_u16_length_prefixed(&cbs, &signature)) 2173 goto err; 2174 if (CBS_len(&signature) > EVP_PKEY_size(pkey)) { 2175 SSLerror(s, SSL_R_WRONG_SIGNATURE_SIZE); 2176 al = SSL_AD_DECODE_ERROR; 2177 goto f_err; 2178 } 2179 if (CBS_len(&cbs) != 0) { 2180 al = SSL_AD_DECODE_ERROR; 2181 SSLerror(s, SSL_R_EXTRA_DATA_IN_MESSAGE); 2182 goto f_err; 2183 } 2184 2185 if (!tls1_transcript_data(s, &hdata, &hdatalen)) { 2186 SSLerror(s, ERR_R_INTERNAL_ERROR); 2187 al = SSL_AD_INTERNAL_ERROR; 2188 goto f_err; 2189 } 2190 if (!EVP_DigestVerifyInit(&mctx, &pctx, md, NULL, pkey)) { 2191 SSLerror(s, ERR_R_EVP_LIB); 2192 al = SSL_AD_INTERNAL_ERROR; 2193 goto f_err; 2194 } 2195 if ((sigalg->flags & SIGALG_FLAG_RSA_PSS) && 2196 (!EVP_PKEY_CTX_set_rsa_padding 2197 (pctx, RSA_PKCS1_PSS_PADDING) || 2198 !EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, -1))) { 2199 al = SSL_AD_INTERNAL_ERROR; 2200 goto f_err; 2201 } 2202 if (sigalg->key_type == EVP_PKEY_GOSTR01 && 2203 EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_VERIFY, 2204 EVP_PKEY_CTRL_GOST_SIG_FORMAT, GOST_SIG_FORMAT_RS_LE, 2205 NULL) <= 0) { 2206 al = SSL_AD_INTERNAL_ERROR; 2207 goto f_err; 2208 } 2209 if (!EVP_DigestVerifyUpdate(&mctx, hdata, hdatalen)) { 2210 SSLerror(s, ERR_R_EVP_LIB); 2211 al = SSL_AD_INTERNAL_ERROR; 2212 goto f_err; 2213 } 2214 if (EVP_DigestVerifyFinal(&mctx, CBS_data(&signature), 2215 CBS_len(&signature)) <= 0) { 2216 al = SSL_AD_DECRYPT_ERROR; 2217 SSLerror(s, SSL_R_BAD_SIGNATURE); 2218 goto f_err; 2219 } 2220 } else if (pkey->type == EVP_PKEY_RSA) { 2221 verify = RSA_verify(NID_md5_sha1, S3I(s)->tmp.cert_verify_md, 2222 MD5_DIGEST_LENGTH + SHA_DIGEST_LENGTH, CBS_data(&signature), 2223 CBS_len(&signature), pkey->pkey.rsa); 2224 if (verify < 0) { 2225 al = SSL_AD_DECRYPT_ERROR; 2226 SSLerror(s, SSL_R_BAD_RSA_DECRYPT); 2227 goto f_err; 2228 } 2229 if (verify == 0) { 2230 al = SSL_AD_DECRYPT_ERROR; 2231 SSLerror(s, SSL_R_BAD_RSA_SIGNATURE); 2232 goto f_err; 2233 } 2234 } else if (pkey->type == EVP_PKEY_EC) { 2235 verify = ECDSA_verify(pkey->save_type, 2236 &(S3I(s)->tmp.cert_verify_md[MD5_DIGEST_LENGTH]), 2237 SHA_DIGEST_LENGTH, CBS_data(&signature), 2238 CBS_len(&signature), pkey->pkey.ec); 2239 if (verify <= 0) { 2240 al = SSL_AD_DECRYPT_ERROR; 2241 SSLerror(s, SSL_R_BAD_ECDSA_SIGNATURE); 2242 goto f_err; 2243 } 2244 #ifndef OPENSSL_NO_GOST 2245 } else if (pkey->type == NID_id_GostR3410_94 || 2246 pkey->type == NID_id_GostR3410_2001) { 2247 unsigned char sigbuf[128]; 2248 unsigned int siglen = sizeof(sigbuf); 2249 EVP_PKEY_CTX *pctx; 2250 int nid; 2251 2252 if (!tls1_transcript_data(s, &hdata, &hdatalen)) { 2253 SSLerror(s, ERR_R_INTERNAL_ERROR); 2254 al = SSL_AD_INTERNAL_ERROR; 2255 goto f_err; 2256 } 2257 if (!EVP_PKEY_get_default_digest_nid(pkey, &nid) || 2258 !(md = EVP_get_digestbynid(nid))) { 2259 SSLerror(s, ERR_R_EVP_LIB); 2260 al = SSL_AD_INTERNAL_ERROR; 2261 goto f_err; 2262 } 2263 if ((pctx = EVP_PKEY_CTX_new(pkey, NULL)) == NULL) { 2264 SSLerror(s, ERR_R_EVP_LIB); 2265 al = SSL_AD_INTERNAL_ERROR; 2266 goto f_err; 2267 } 2268 if (!EVP_DigestInit_ex(&mctx, md, NULL) || 2269 !EVP_DigestUpdate(&mctx, hdata, hdatalen) || 2270 !EVP_DigestFinal(&mctx, sigbuf, &siglen) || 2271 (EVP_PKEY_verify_init(pctx) <= 0) || 2272 (EVP_PKEY_CTX_set_signature_md(pctx, md) <= 0) || 2273 (EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_VERIFY, 2274 EVP_PKEY_CTRL_GOST_SIG_FORMAT, 2275 GOST_SIG_FORMAT_RS_LE, NULL) <= 0)) { 2276 SSLerror(s, ERR_R_EVP_LIB); 2277 al = SSL_AD_INTERNAL_ERROR; 2278 EVP_PKEY_CTX_free(pctx); 2279 goto f_err; 2280 } 2281 if (EVP_PKEY_verify(pctx, CBS_data(&signature), 2282 CBS_len(&signature), sigbuf, siglen) <= 0) { 2283 al = SSL_AD_DECRYPT_ERROR; 2284 SSLerror(s, SSL_R_BAD_SIGNATURE); 2285 EVP_PKEY_CTX_free(pctx); 2286 goto f_err; 2287 } 2288 2289 EVP_PKEY_CTX_free(pctx); 2290 #endif 2291 } else { 2292 SSLerror(s, ERR_R_INTERNAL_ERROR); 2293 al = SSL_AD_UNSUPPORTED_CERTIFICATE; 2294 goto f_err; 2295 } 2296 2297 ret = 1; 2298 if (0) { 2299 truncated: 2300 al = SSL_AD_DECODE_ERROR; 2301 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 2302 f_err: 2303 ssl3_send_alert(s, SSL3_AL_FATAL, al); 2304 } 2305 end: 2306 tls1_transcript_free(s); 2307 err: 2308 EVP_MD_CTX_cleanup(&mctx); 2309 EVP_PKEY_free(pkey); 2310 return (ret); 2311 } 2312 2313 int 2314 ssl3_get_client_certificate(SSL *s) 2315 { 2316 CBS cbs, client_certs; 2317 int i, ok, al, ret = -1; 2318 X509 *x = NULL; 2319 long n; 2320 const unsigned char *q; 2321 STACK_OF(X509) *sk = NULL; 2322 2323 n = ssl3_get_message(s, SSL3_ST_SR_CERT_A, SSL3_ST_SR_CERT_B, 2324 -1, s->internal->max_cert_list, &ok); 2325 if (!ok) 2326 return ((int)n); 2327 2328 if (S3I(s)->tmp.message_type == SSL3_MT_CLIENT_KEY_EXCHANGE) { 2329 if ((s->verify_mode & SSL_VERIFY_PEER) && 2330 (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { 2331 SSLerror(s, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); 2332 al = SSL_AD_HANDSHAKE_FAILURE; 2333 goto f_err; 2334 } 2335 /* 2336 * If tls asked for a client cert, 2337 * the client must return a 0 list. 2338 */ 2339 if (S3I(s)->tmp.cert_request) { 2340 SSLerror(s, SSL_R_TLS_PEER_DID_NOT_RESPOND_WITH_CERTIFICATE_LIST 2341 ); 2342 al = SSL_AD_UNEXPECTED_MESSAGE; 2343 goto f_err; 2344 } 2345 S3I(s)->tmp.reuse_message = 1; 2346 return (1); 2347 } 2348 2349 if (S3I(s)->tmp.message_type != SSL3_MT_CERTIFICATE) { 2350 al = SSL_AD_UNEXPECTED_MESSAGE; 2351 SSLerror(s, SSL_R_WRONG_MESSAGE_TYPE); 2352 goto f_err; 2353 } 2354 2355 if (n < 0) 2356 goto truncated; 2357 2358 CBS_init(&cbs, s->internal->init_msg, n); 2359 2360 if ((sk = sk_X509_new_null()) == NULL) { 2361 SSLerror(s, ERR_R_MALLOC_FAILURE); 2362 goto err; 2363 } 2364 2365 if (!CBS_get_u24_length_prefixed(&cbs, &client_certs) || 2366 CBS_len(&cbs) != 0) 2367 goto truncated; 2368 2369 while (CBS_len(&client_certs) > 0) { 2370 CBS cert; 2371 2372 if (!CBS_get_u24_length_prefixed(&client_certs, &cert)) { 2373 al = SSL_AD_DECODE_ERROR; 2374 SSLerror(s, SSL_R_CERT_LENGTH_MISMATCH); 2375 goto f_err; 2376 } 2377 2378 q = CBS_data(&cert); 2379 x = d2i_X509(NULL, &q, CBS_len(&cert)); 2380 if (x == NULL) { 2381 SSLerror(s, ERR_R_ASN1_LIB); 2382 goto err; 2383 } 2384 if (q != CBS_data(&cert) + CBS_len(&cert)) { 2385 al = SSL_AD_DECODE_ERROR; 2386 SSLerror(s, SSL_R_CERT_LENGTH_MISMATCH); 2387 goto f_err; 2388 } 2389 if (!sk_X509_push(sk, x)) { 2390 SSLerror(s, ERR_R_MALLOC_FAILURE); 2391 goto err; 2392 } 2393 x = NULL; 2394 } 2395 2396 if (sk_X509_num(sk) <= 0) { 2397 /* 2398 * TLS does not mind 0 certs returned. 2399 * Fail for TLS only if we required a certificate. 2400 */ 2401 if ((s->verify_mode & SSL_VERIFY_PEER) && 2402 (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { 2403 SSLerror(s, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); 2404 al = SSL_AD_HANDSHAKE_FAILURE; 2405 goto f_err; 2406 } 2407 /* No client certificate so free transcript. */ 2408 tls1_transcript_free(s); 2409 } else { 2410 i = ssl_verify_cert_chain(s, sk); 2411 if (i <= 0) { 2412 al = ssl_verify_alarm_type(s->verify_result); 2413 SSLerror(s, SSL_R_NO_CERTIFICATE_RETURNED); 2414 goto f_err; 2415 } 2416 } 2417 2418 X509_free(s->session->peer); 2419 s->session->peer = sk_X509_shift(sk); 2420 s->session->verify_result = s->verify_result; 2421 2422 /* 2423 * With the current implementation, sess_cert will always be NULL 2424 * when we arrive here 2425 */ 2426 if (SSI(s)->sess_cert == NULL) { 2427 SSI(s)->sess_cert = ssl_sess_cert_new(); 2428 if (SSI(s)->sess_cert == NULL) { 2429 SSLerror(s, ERR_R_MALLOC_FAILURE); 2430 goto err; 2431 } 2432 } 2433 sk_X509_pop_free(SSI(s)->sess_cert->cert_chain, X509_free); 2434 SSI(s)->sess_cert->cert_chain = sk; 2435 2436 /* 2437 * Inconsistency alert: cert_chain does *not* include the 2438 * peer's own certificate, while we do include it in s3_clnt.c 2439 */ 2440 2441 sk = NULL; 2442 2443 ret = 1; 2444 if (0) { 2445 truncated: 2446 al = SSL_AD_DECODE_ERROR; 2447 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 2448 f_err: 2449 ssl3_send_alert(s, SSL3_AL_FATAL, al); 2450 } 2451 err: 2452 X509_free(x); 2453 sk_X509_pop_free(sk, X509_free); 2454 2455 return (ret); 2456 } 2457 2458 int 2459 ssl3_send_server_certificate(SSL *s) 2460 { 2461 CBB cbb, server_cert; 2462 CERT_PKEY *cpk; 2463 2464 /* 2465 * Server Certificate - RFC 5246, section 7.4.2. 2466 */ 2467 2468 memset(&cbb, 0, sizeof(cbb)); 2469 2470 if (S3I(s)->hs.state == SSL3_ST_SW_CERT_A) { 2471 if ((cpk = ssl_get_server_send_pkey(s)) == NULL) { 2472 SSLerror(s, ERR_R_INTERNAL_ERROR); 2473 return (0); 2474 } 2475 2476 if (!ssl3_handshake_msg_start(s, &cbb, &server_cert, 2477 SSL3_MT_CERTIFICATE)) 2478 goto err; 2479 if (!ssl3_output_cert_chain(s, &server_cert, cpk)) 2480 goto err; 2481 if (!ssl3_handshake_msg_finish(s, &cbb)) 2482 goto err; 2483 2484 S3I(s)->hs.state = SSL3_ST_SW_CERT_B; 2485 } 2486 2487 /* SSL3_ST_SW_CERT_B */ 2488 return (ssl3_handshake_write(s)); 2489 2490 err: 2491 CBB_cleanup(&cbb); 2492 2493 return (0); 2494 } 2495 2496 /* send a new session ticket (not necessarily for a new session) */ 2497 int 2498 ssl3_send_newsession_ticket(SSL *s) 2499 { 2500 CBB cbb, session_ticket, ticket; 2501 SSL_CTX *tctx = s->initial_ctx; 2502 size_t enc_session_len, enc_session_max_len, hmac_len; 2503 size_t session_len = 0; 2504 unsigned char *enc_session = NULL, *session = NULL; 2505 unsigned char iv[EVP_MAX_IV_LENGTH]; 2506 unsigned char key_name[16]; 2507 unsigned char *hmac; 2508 unsigned int hlen; 2509 EVP_CIPHER_CTX ctx; 2510 HMAC_CTX hctx; 2511 int len; 2512 2513 /* 2514 * New Session Ticket - RFC 5077, section 3.3. 2515 */ 2516 2517 EVP_CIPHER_CTX_init(&ctx); 2518 HMAC_CTX_init(&hctx); 2519 2520 memset(&cbb, 0, sizeof(cbb)); 2521 2522 if (S3I(s)->hs.state == SSL3_ST_SW_SESSION_TICKET_A) { 2523 if (!ssl3_handshake_msg_start(s, &cbb, &session_ticket, 2524 SSL3_MT_NEWSESSION_TICKET)) 2525 goto err; 2526 2527 if (!SSL_SESSION_ticket(s->session, &session, &session_len)) 2528 goto err; 2529 if (session_len > 0xffff) 2530 goto err; 2531 2532 /* 2533 * Initialize HMAC and cipher contexts. If callback is present 2534 * it does all the work, otherwise use generated values from 2535 * parent context. 2536 */ 2537 if (tctx->internal->tlsext_ticket_key_cb != NULL) { 2538 if (tctx->internal->tlsext_ticket_key_cb(s, 2539 key_name, iv, &ctx, &hctx, 1) < 0) { 2540 EVP_CIPHER_CTX_cleanup(&ctx); 2541 goto err; 2542 } 2543 } else { 2544 arc4random_buf(iv, 16); 2545 EVP_EncryptInit_ex(&ctx, EVP_aes_128_cbc(), NULL, 2546 tctx->internal->tlsext_tick_aes_key, iv); 2547 HMAC_Init_ex(&hctx, tctx->internal->tlsext_tick_hmac_key, 2548 16, EVP_sha256(), NULL); 2549 memcpy(key_name, tctx->internal->tlsext_tick_key_name, 16); 2550 } 2551 2552 /* Encrypt the session state. */ 2553 enc_session_max_len = session_len + EVP_MAX_BLOCK_LENGTH; 2554 if ((enc_session = calloc(1, enc_session_max_len)) == NULL) 2555 goto err; 2556 enc_session_len = 0; 2557 if (!EVP_EncryptUpdate(&ctx, enc_session, &len, session, 2558 session_len)) 2559 goto err; 2560 enc_session_len += len; 2561 if (!EVP_EncryptFinal_ex(&ctx, enc_session + enc_session_len, 2562 &len)) 2563 goto err; 2564 enc_session_len += len; 2565 2566 if (enc_session_len > enc_session_max_len) 2567 goto err; 2568 2569 /* Generate the HMAC. */ 2570 if (!HMAC_Update(&hctx, key_name, sizeof(key_name))) 2571 goto err; 2572 if (!HMAC_Update(&hctx, iv, EVP_CIPHER_CTX_iv_length(&ctx))) 2573 goto err; 2574 if (!HMAC_Update(&hctx, enc_session, enc_session_len)) 2575 goto err; 2576 2577 if ((hmac_len = HMAC_size(&hctx)) <= 0) 2578 goto err; 2579 2580 /* 2581 * Ticket lifetime hint (advisory only): 2582 * We leave this unspecified for resumed session 2583 * (for simplicity), and guess that tickets for new 2584 * sessions will live as long as their sessions. 2585 */ 2586 if (!CBB_add_u32(&session_ticket, 2587 s->internal->hit ? 0 : s->session->timeout)) 2588 goto err; 2589 2590 if (!CBB_add_u16_length_prefixed(&session_ticket, &ticket)) 2591 goto err; 2592 if (!CBB_add_bytes(&ticket, key_name, sizeof(key_name))) 2593 goto err; 2594 if (!CBB_add_bytes(&ticket, iv, EVP_CIPHER_CTX_iv_length(&ctx))) 2595 goto err; 2596 if (!CBB_add_bytes(&ticket, enc_session, enc_session_len)) 2597 goto err; 2598 if (!CBB_add_space(&ticket, &hmac, hmac_len)) 2599 goto err; 2600 2601 if (!HMAC_Final(&hctx, hmac, &hlen)) 2602 goto err; 2603 if (hlen != hmac_len) 2604 goto err; 2605 2606 if (!ssl3_handshake_msg_finish(s, &cbb)) 2607 goto err; 2608 2609 S3I(s)->hs.state = SSL3_ST_SW_SESSION_TICKET_B; 2610 } 2611 2612 EVP_CIPHER_CTX_cleanup(&ctx); 2613 HMAC_CTX_cleanup(&hctx); 2614 freezero(session, session_len); 2615 free(enc_session); 2616 2617 /* SSL3_ST_SW_SESSION_TICKET_B */ 2618 return (ssl3_handshake_write(s)); 2619 2620 err: 2621 CBB_cleanup(&cbb); 2622 EVP_CIPHER_CTX_cleanup(&ctx); 2623 HMAC_CTX_cleanup(&hctx); 2624 freezero(session, session_len); 2625 free(enc_session); 2626 2627 return (-1); 2628 } 2629 2630 int 2631 ssl3_send_cert_status(SSL *s) 2632 { 2633 CBB cbb, certstatus, ocspresp; 2634 2635 memset(&cbb, 0, sizeof(cbb)); 2636 2637 if (S3I(s)->hs.state == SSL3_ST_SW_CERT_STATUS_A) { 2638 if (!ssl3_handshake_msg_start(s, &cbb, &certstatus, 2639 SSL3_MT_CERTIFICATE_STATUS)) 2640 goto err; 2641 if (!CBB_add_u8(&certstatus, s->tlsext_status_type)) 2642 goto err; 2643 if (!CBB_add_u24_length_prefixed(&certstatus, &ocspresp)) 2644 goto err; 2645 if (!CBB_add_bytes(&ocspresp, s->internal->tlsext_ocsp_resp, 2646 s->internal->tlsext_ocsp_resp_len)) 2647 goto err; 2648 if (!ssl3_handshake_msg_finish(s, &cbb)) 2649 goto err; 2650 2651 S3I(s)->hs.state = SSL3_ST_SW_CERT_STATUS_B; 2652 } 2653 2654 /* SSL3_ST_SW_CERT_STATUS_B */ 2655 return (ssl3_handshake_write(s)); 2656 2657 err: 2658 CBB_cleanup(&cbb); 2659 2660 return (-1); 2661 } 2662