xref: /openbsd-src/lib/libssl/ssl_clnt.c (revision 25c4e8bd056e974b28f4a0ffd39d76c190a56013)
1 /* $OpenBSD: ssl_clnt.c,v 1.151 2022/07/03 14:52:39 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 <limits.h>
152 #include <stdint.h>
153 #include <stdio.h>
154 
155 #include <openssl/bn.h>
156 #include <openssl/buffer.h>
157 #include <openssl/curve25519.h>
158 #include <openssl/dh.h>
159 #include <openssl/evp.h>
160 #include <openssl/md5.h>
161 #include <openssl/objects.h>
162 #include <openssl/opensslconf.h>
163 
164 #ifndef OPENSSL_NO_ENGINE
165 #include <openssl/engine.h>
166 #endif
167 #ifndef OPENSSL_NO_GOST
168 #include <openssl/gost.h>
169 #endif
170 
171 #include "bytestring.h"
172 #include "dtls_locl.h"
173 #include "ssl_locl.h"
174 #include "ssl_sigalgs.h"
175 #include "ssl_tlsext.h"
176 
177 static int ca_dn_cmp(const X509_NAME * const *a, const X509_NAME * const *b);
178 
179 int
180 ssl3_connect(SSL *s)
181 {
182 	int new_state, state, skip = 0;
183 	int ret = -1;
184 
185 	ERR_clear_error();
186 	errno = 0;
187 
188 	s->internal->in_handshake++;
189 	if (!SSL_in_init(s) || SSL_in_before(s))
190 		SSL_clear(s);
191 
192 	for (;;) {
193 		state = s->s3->hs.state;
194 
195 		switch (s->s3->hs.state) {
196 		case SSL_ST_RENEGOTIATE:
197 			s->internal->renegotiate = 1;
198 			s->s3->hs.state = SSL_ST_CONNECT;
199 			s->ctx->internal->stats.sess_connect_renegotiate++;
200 			/* break */
201 		case SSL_ST_BEFORE:
202 		case SSL_ST_CONNECT:
203 		case SSL_ST_BEFORE|SSL_ST_CONNECT:
204 		case SSL_ST_OK|SSL_ST_CONNECT:
205 
206 			s->server = 0;
207 
208 			ssl_info_callback(s, SSL_CB_HANDSHAKE_START, 1);
209 
210 			if (!ssl_legacy_stack_version(s, s->version)) {
211 				SSLerror(s, ERR_R_INTERNAL_ERROR);
212 				ret = -1;
213 				goto end;
214 			}
215 
216 			if (!ssl_supported_tls_version_range(s,
217 			    &s->s3->hs.our_min_tls_version,
218 			    &s->s3->hs.our_max_tls_version)) {
219 				SSLerror(s, SSL_R_NO_PROTOCOLS_AVAILABLE);
220 				ret = -1;
221 				goto end;
222 			}
223 
224 			if (!ssl_security_version(s,
225 			    s->s3->hs.our_min_tls_version)) {
226 				SSLerror(s, SSL_R_VERSION_TOO_LOW);
227 				ret = -1;
228 				goto end;
229 			}
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 			if (!ssl_init_wbio_buffer(s, 0)) {
240 				ret = -1;
241 				goto end;
242 			}
243 
244 			/* don't push the buffering BIO quite yet */
245 
246 			if (!tls1_transcript_init(s)) {
247 				ret = -1;
248 				goto end;
249 			}
250 
251 			s->s3->hs.state = SSL3_ST_CW_CLNT_HELLO_A;
252 			s->ctx->internal->stats.sess_connect++;
253 			s->internal->init_num = 0;
254 
255 			if (SSL_is_dtls(s)) {
256 				/* mark client_random uninitialized */
257 				memset(s->s3->client_random, 0,
258 				    sizeof(s->s3->client_random));
259 				s->d1->send_cookie = 0;
260 				s->internal->hit = 0;
261 			}
262 			break;
263 
264 		case SSL3_ST_CW_CLNT_HELLO_A:
265 		case SSL3_ST_CW_CLNT_HELLO_B:
266 			s->internal->shutdown = 0;
267 
268 			if (SSL_is_dtls(s)) {
269 				/* every DTLS ClientHello resets Finished MAC */
270 				tls1_transcript_reset(s);
271 
272 				dtls1_start_timer(s);
273 			}
274 
275 			ret = ssl3_send_client_hello(s);
276 			if (ret <= 0)
277 				goto end;
278 
279 			if (SSL_is_dtls(s) && s->d1->send_cookie) {
280 				s->s3->hs.state = SSL3_ST_CW_FLUSH;
281 				s->s3->hs.tls12.next_state = SSL3_ST_CR_SRVR_HELLO_A;
282 			} else
283 				s->s3->hs.state = SSL3_ST_CR_SRVR_HELLO_A;
284 
285 			s->internal->init_num = 0;
286 
287 			/* turn on buffering for the next lot of output */
288 			if (s->bbio != s->wbio)
289 				s->wbio = BIO_push(s->bbio, s->wbio);
290 
291 			break;
292 
293 		case SSL3_ST_CR_SRVR_HELLO_A:
294 		case SSL3_ST_CR_SRVR_HELLO_B:
295 			ret = ssl3_get_server_hello(s);
296 			if (ret <= 0)
297 				goto end;
298 
299 			if (s->internal->hit) {
300 				s->s3->hs.state = SSL3_ST_CR_FINISHED_A;
301 				if (!SSL_is_dtls(s)) {
302 					if (s->internal->tlsext_ticket_expected) {
303 						/* receive renewed session ticket */
304 						s->s3->hs.state = SSL3_ST_CR_SESSION_TICKET_A;
305 					}
306 
307 					/* No client certificate verification. */
308 					tls1_transcript_free(s);
309 				}
310 			} else if (SSL_is_dtls(s)) {
311 				s->s3->hs.state = DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A;
312 			} else {
313 				s->s3->hs.state = SSL3_ST_CR_CERT_A;
314 			}
315 			s->internal->init_num = 0;
316 			break;
317 
318 		case DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A:
319 		case DTLS1_ST_CR_HELLO_VERIFY_REQUEST_B:
320 			ret = ssl3_get_dtls_hello_verify(s);
321 			if (ret <= 0)
322 				goto end;
323 			dtls1_stop_timer(s);
324 			if (s->d1->send_cookie) /* start again, with a cookie */
325 				s->s3->hs.state = SSL3_ST_CW_CLNT_HELLO_A;
326 			else
327 				s->s3->hs.state = SSL3_ST_CR_CERT_A;
328 			s->internal->init_num = 0;
329 			break;
330 
331 		case SSL3_ST_CR_CERT_A:
332 		case SSL3_ST_CR_CERT_B:
333 			ret = ssl3_check_finished(s);
334 			if (ret <= 0)
335 				goto end;
336 			if (ret == 2) {
337 				s->internal->hit = 1;
338 				if (s->internal->tlsext_ticket_expected)
339 					s->s3->hs.state = SSL3_ST_CR_SESSION_TICKET_A;
340 				else
341 					s->s3->hs.state = SSL3_ST_CR_FINISHED_A;
342 				s->internal->init_num = 0;
343 				break;
344 			}
345 			/* Check if it is anon DH/ECDH. */
346 			if (!(s->s3->hs.cipher->algorithm_auth &
347 			    SSL_aNULL)) {
348 				ret = ssl3_get_server_certificate(s);
349 				if (ret <= 0)
350 					goto end;
351 				if (s->internal->tlsext_status_expected)
352 					s->s3->hs.state = SSL3_ST_CR_CERT_STATUS_A;
353 				else
354 					s->s3->hs.state = SSL3_ST_CR_KEY_EXCH_A;
355 			} else {
356 				skip = 1;
357 				s->s3->hs.state = SSL3_ST_CR_KEY_EXCH_A;
358 			}
359 			s->internal->init_num = 0;
360 			break;
361 
362 		case SSL3_ST_CR_KEY_EXCH_A:
363 		case SSL3_ST_CR_KEY_EXCH_B:
364 			ret = ssl3_get_server_key_exchange(s);
365 			if (ret <= 0)
366 				goto end;
367 			s->s3->hs.state = SSL3_ST_CR_CERT_REQ_A;
368 			s->internal->init_num = 0;
369 
370 			/*
371 			 * At this point we check that we have the
372 			 * required stuff from the server.
373 			 */
374 			if (!ssl3_check_cert_and_algorithm(s)) {
375 				ret = -1;
376 				goto end;
377 			}
378 			break;
379 
380 		case SSL3_ST_CR_CERT_REQ_A:
381 		case SSL3_ST_CR_CERT_REQ_B:
382 			ret = ssl3_get_certificate_request(s);
383 			if (ret <= 0)
384 				goto end;
385 			s->s3->hs.state = SSL3_ST_CR_SRVR_DONE_A;
386 			s->internal->init_num = 0;
387 			break;
388 
389 		case SSL3_ST_CR_SRVR_DONE_A:
390 		case SSL3_ST_CR_SRVR_DONE_B:
391 			ret = ssl3_get_server_done(s);
392 			if (ret <= 0)
393 				goto end;
394 			if (SSL_is_dtls(s))
395 				dtls1_stop_timer(s);
396 			if (s->s3->hs.tls12.cert_request)
397 				s->s3->hs.state = SSL3_ST_CW_CERT_A;
398 			else
399 				s->s3->hs.state = SSL3_ST_CW_KEY_EXCH_A;
400 			s->internal->init_num = 0;
401 
402 			break;
403 
404 		case SSL3_ST_CW_CERT_A:
405 		case SSL3_ST_CW_CERT_B:
406 		case SSL3_ST_CW_CERT_C:
407 		case SSL3_ST_CW_CERT_D:
408 			if (SSL_is_dtls(s))
409 				dtls1_start_timer(s);
410 			ret = ssl3_send_client_certificate(s);
411 			if (ret <= 0)
412 				goto end;
413 			s->s3->hs.state = SSL3_ST_CW_KEY_EXCH_A;
414 			s->internal->init_num = 0;
415 			break;
416 
417 		case SSL3_ST_CW_KEY_EXCH_A:
418 		case SSL3_ST_CW_KEY_EXCH_B:
419 			if (SSL_is_dtls(s))
420 				dtls1_start_timer(s);
421 			ret = ssl3_send_client_key_exchange(s);
422 			if (ret <= 0)
423 				goto end;
424 			/*
425 			 * EAY EAY EAY need to check for DH fix cert
426 			 * sent back
427 			 */
428 			/*
429 			 * For TLS, cert_req is set to 2, so a cert chain
430 			 * of nothing is sent, but no verify packet is sent
431 			 */
432 			/*
433 			 * XXX: For now, we do not support client
434 			 * authentication in ECDH cipher suites with
435 			 * ECDH (rather than ECDSA) certificates.
436 			 * We need to skip the certificate verify
437 			 * message when client's ECDH public key is sent
438 			 * inside the client certificate.
439 			 */
440 			if (s->s3->hs.tls12.cert_request == 1) {
441 				s->s3->hs.state = SSL3_ST_CW_CERT_VRFY_A;
442 			} else {
443 				s->s3->hs.state = SSL3_ST_CW_CHANGE_A;
444 				s->s3->change_cipher_spec = 0;
445 			}
446 			if (!SSL_is_dtls(s)) {
447 				if (s->s3->flags & TLS1_FLAGS_SKIP_CERT_VERIFY) {
448 					s->s3->hs.state = SSL3_ST_CW_CHANGE_A;
449 					s->s3->change_cipher_spec = 0;
450 				}
451 			}
452 
453 			s->internal->init_num = 0;
454 			break;
455 
456 		case SSL3_ST_CW_CERT_VRFY_A:
457 		case SSL3_ST_CW_CERT_VRFY_B:
458 			if (SSL_is_dtls(s))
459 				dtls1_start_timer(s);
460 			ret = ssl3_send_client_verify(s);
461 			if (ret <= 0)
462 				goto end;
463 			s->s3->hs.state = SSL3_ST_CW_CHANGE_A;
464 			s->internal->init_num = 0;
465 			s->s3->change_cipher_spec = 0;
466 			break;
467 
468 		case SSL3_ST_CW_CHANGE_A:
469 		case SSL3_ST_CW_CHANGE_B:
470 			if (SSL_is_dtls(s) && !s->internal->hit)
471 				dtls1_start_timer(s);
472 			ret = ssl3_send_change_cipher_spec(s,
473 			    SSL3_ST_CW_CHANGE_A, SSL3_ST_CW_CHANGE_B);
474 			if (ret <= 0)
475 				goto end;
476 
477 			s->s3->hs.state = SSL3_ST_CW_FINISHED_A;
478 			s->internal->init_num = 0;
479 			s->session->cipher = s->s3->hs.cipher;
480 
481 			if (!tls1_setup_key_block(s)) {
482 				ret = -1;
483 				goto end;
484 			}
485 			if (!tls1_change_write_cipher_state(s)) {
486 				ret = -1;
487 				goto end;
488 			}
489 			break;
490 
491 		case SSL3_ST_CW_FINISHED_A:
492 		case SSL3_ST_CW_FINISHED_B:
493 			if (SSL_is_dtls(s) && !s->internal->hit)
494 				dtls1_start_timer(s);
495 			ret = ssl3_send_finished(s, SSL3_ST_CW_FINISHED_A,
496 			    SSL3_ST_CW_FINISHED_B);
497 			if (ret <= 0)
498 				goto end;
499 			if (!SSL_is_dtls(s))
500 				s->s3->flags |= SSL3_FLAGS_CCS_OK;
501 			s->s3->hs.state = SSL3_ST_CW_FLUSH;
502 
503 			/* clear flags */
504 			if (s->internal->hit) {
505 				s->s3->hs.tls12.next_state = SSL_ST_OK;
506 			} else {
507 				/* Allow NewSessionTicket if ticket expected */
508 				if (s->internal->tlsext_ticket_expected)
509 					s->s3->hs.tls12.next_state =
510 					    SSL3_ST_CR_SESSION_TICKET_A;
511 				else
512 					s->s3->hs.tls12.next_state =
513 					    SSL3_ST_CR_FINISHED_A;
514 			}
515 			s->internal->init_num = 0;
516 			break;
517 
518 		case SSL3_ST_CR_SESSION_TICKET_A:
519 		case SSL3_ST_CR_SESSION_TICKET_B:
520 			ret = ssl3_get_new_session_ticket(s);
521 			if (ret <= 0)
522 				goto end;
523 			s->s3->hs.state = SSL3_ST_CR_FINISHED_A;
524 			s->internal->init_num = 0;
525 			break;
526 
527 		case SSL3_ST_CR_CERT_STATUS_A:
528 		case SSL3_ST_CR_CERT_STATUS_B:
529 			ret = ssl3_get_cert_status(s);
530 			if (ret <= 0)
531 				goto end;
532 			s->s3->hs.state = SSL3_ST_CR_KEY_EXCH_A;
533 			s->internal->init_num = 0;
534 			break;
535 
536 		case SSL3_ST_CR_FINISHED_A:
537 		case SSL3_ST_CR_FINISHED_B:
538 			if (SSL_is_dtls(s))
539 				s->d1->change_cipher_spec_ok = 1;
540 			else
541 				s->s3->flags |= SSL3_FLAGS_CCS_OK;
542 			ret = ssl3_get_finished(s, SSL3_ST_CR_FINISHED_A,
543 			    SSL3_ST_CR_FINISHED_B);
544 			if (ret <= 0)
545 				goto end;
546 			if (SSL_is_dtls(s))
547 				dtls1_stop_timer(s);
548 
549 			if (s->internal->hit)
550 				s->s3->hs.state = SSL3_ST_CW_CHANGE_A;
551 			else
552 				s->s3->hs.state = SSL_ST_OK;
553 			s->internal->init_num = 0;
554 			break;
555 
556 		case SSL3_ST_CW_FLUSH:
557 			s->internal->rwstate = SSL_WRITING;
558 			if (BIO_flush(s->wbio) <= 0) {
559 				if (SSL_is_dtls(s)) {
560 					/* If the write error was fatal, stop trying */
561 					if (!BIO_should_retry(s->wbio)) {
562 						s->internal->rwstate = SSL_NOTHING;
563 						s->s3->hs.state = s->s3->hs.tls12.next_state;
564 					}
565 				}
566 				ret = -1;
567 				goto end;
568 			}
569 			s->internal->rwstate = SSL_NOTHING;
570 			s->s3->hs.state = s->s3->hs.tls12.next_state;
571 			break;
572 
573 		case SSL_ST_OK:
574 			/* clean a few things up */
575 			tls1_cleanup_key_block(s);
576 
577 			if (s->s3->handshake_transcript != NULL) {
578 				SSLerror(s, ERR_R_INTERNAL_ERROR);
579 				ret = -1;
580 				goto end;
581 			}
582 
583 			if (!SSL_is_dtls(s))
584 				ssl3_release_init_buffer(s);
585 
586 			ssl_free_wbio_buffer(s);
587 
588 			s->internal->init_num = 0;
589 			s->internal->renegotiate = 0;
590 			s->internal->new_session = 0;
591 
592 			ssl_update_cache(s, SSL_SESS_CACHE_CLIENT);
593 			if (s->internal->hit)
594 				s->ctx->internal->stats.sess_hit++;
595 
596 			ret = 1;
597 			/* s->server=0; */
598 			s->internal->handshake_func = ssl3_connect;
599 			s->ctx->internal->stats.sess_connect_good++;
600 
601 			ssl_info_callback(s, SSL_CB_HANDSHAKE_DONE, 1);
602 
603 			if (SSL_is_dtls(s)) {
604 				/* done with handshaking */
605 				s->d1->handshake_read_seq = 0;
606 				s->d1->next_handshake_write_seq = 0;
607 			}
608 
609 			goto end;
610 			/* break; */
611 
612 		default:
613 			SSLerror(s, SSL_R_UNKNOWN_STATE);
614 			ret = -1;
615 			goto end;
616 			/* break; */
617 		}
618 
619 		/* did we do anything */
620 		if (!s->s3->hs.tls12.reuse_message && !skip) {
621 			if (s->internal->debug) {
622 				if ((ret = BIO_flush(s->wbio)) <= 0)
623 					goto end;
624 			}
625 
626 			if (s->s3->hs.state != state) {
627 				new_state = s->s3->hs.state;
628 				s->s3->hs.state = state;
629 				ssl_info_callback(s, SSL_CB_CONNECT_LOOP, 1);
630 				s->s3->hs.state = new_state;
631 			}
632 		}
633 		skip = 0;
634 	}
635 
636  end:
637 	s->internal->in_handshake--;
638 	ssl_info_callback(s, SSL_CB_CONNECT_EXIT, ret);
639 
640 	return (ret);
641 }
642 
643 int
644 ssl3_send_client_hello(SSL *s)
645 {
646 	CBB cbb, client_hello, session_id, cookie, cipher_suites;
647 	CBB compression_methods;
648 	uint16_t max_version;
649 	size_t sl;
650 
651 	memset(&cbb, 0, sizeof(cbb));
652 
653 	if (s->s3->hs.state == SSL3_ST_CW_CLNT_HELLO_A) {
654 		SSL_SESSION *sess = s->session;
655 
656 		if (!ssl_max_supported_version(s, &max_version)) {
657 			SSLerror(s, SSL_R_NO_PROTOCOLS_AVAILABLE);
658 			return (-1);
659 		}
660 		s->version = max_version;
661 
662 		if (sess == NULL || sess->ssl_version != s->version ||
663 		    (sess->session_id_length == 0 && sess->tlsext_tick == NULL) ||
664 		    sess->not_resumable) {
665 			if (!ssl_get_new_session(s, 0))
666 				goto err;
667 		}
668 		/* else use the pre-loaded session */
669 
670 		/*
671 		 * If a DTLS ClientHello message is being resent after a
672 		 * HelloVerifyRequest, we must retain the original client
673 		 * random value.
674 		 */
675 		if (!SSL_is_dtls(s) || s->d1->send_cookie == 0)
676 			arc4random_buf(s->s3->client_random, SSL3_RANDOM_SIZE);
677 
678 		if (!ssl3_handshake_msg_start(s, &cbb, &client_hello,
679 		    SSL3_MT_CLIENT_HELLO))
680 			goto err;
681 
682 		if (!CBB_add_u16(&client_hello, s->version))
683 			goto err;
684 
685 		/* Random stuff */
686 		if (!CBB_add_bytes(&client_hello, s->s3->client_random,
687 		    sizeof(s->s3->client_random)))
688 			goto err;
689 
690 		/* Session ID */
691 		if (!CBB_add_u8_length_prefixed(&client_hello, &session_id))
692 			goto err;
693 		if (!s->internal->new_session &&
694 		    s->session->session_id_length > 0) {
695 			sl = s->session->session_id_length;
696 			if (sl > sizeof(s->session->session_id)) {
697 				SSLerror(s, ERR_R_INTERNAL_ERROR);
698 				goto err;
699 			}
700 			if (!CBB_add_bytes(&session_id,
701 			    s->session->session_id, sl))
702 				goto err;
703 		}
704 
705 		/* DTLS Cookie. */
706 		if (SSL_is_dtls(s)) {
707 			if (s->d1->cookie_len > sizeof(s->d1->cookie)) {
708 				SSLerror(s, ERR_R_INTERNAL_ERROR);
709 				goto err;
710 			}
711 			if (!CBB_add_u8_length_prefixed(&client_hello, &cookie))
712 				goto err;
713 			if (!CBB_add_bytes(&cookie, s->d1->cookie,
714 			    s->d1->cookie_len))
715 				goto err;
716 		}
717 
718 		/* Ciphers supported */
719 		if (!CBB_add_u16_length_prefixed(&client_hello, &cipher_suites))
720 			return 0;
721 		if (!ssl_cipher_list_to_bytes(s, SSL_get_ciphers(s),
722 		    &cipher_suites)) {
723 			SSLerror(s, SSL_R_NO_CIPHERS_AVAILABLE);
724 			goto err;
725 		}
726 
727 		/* Add in compression methods (null) */
728 		if (!CBB_add_u8_length_prefixed(&client_hello,
729 		    &compression_methods))
730 			goto err;
731 		if (!CBB_add_u8(&compression_methods, 0))
732 			goto err;
733 
734 		/* TLS extensions */
735 		if (!tlsext_client_build(s, SSL_TLSEXT_MSG_CH, &client_hello)) {
736 			SSLerror(s, ERR_R_INTERNAL_ERROR);
737 			goto err;
738 		}
739 
740 		if (!ssl3_handshake_msg_finish(s, &cbb))
741 			goto err;
742 
743 		s->s3->hs.state = SSL3_ST_CW_CLNT_HELLO_B;
744 	}
745 
746 	/* SSL3_ST_CW_CLNT_HELLO_B */
747 	return (ssl3_handshake_write(s));
748 
749  err:
750 	CBB_cleanup(&cbb);
751 
752 	return (-1);
753 }
754 
755 int
756 ssl3_get_dtls_hello_verify(SSL *s)
757 {
758 	CBS hello_verify_request, cookie;
759 	size_t cookie_len;
760 	uint16_t ssl_version;
761 	int al, ret;
762 
763 	if ((ret = ssl3_get_message(s, DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A,
764 	    DTLS1_ST_CR_HELLO_VERIFY_REQUEST_B, -1, s->internal->max_cert_list)) <= 0)
765 		return ret;
766 
767 	if (s->s3->hs.tls12.message_type != DTLS1_MT_HELLO_VERIFY_REQUEST) {
768 		s->d1->send_cookie = 0;
769 		s->s3->hs.tls12.reuse_message = 1;
770 		return (1);
771 	}
772 
773 	if (s->internal->init_num < 0)
774 		goto decode_err;
775 
776 	CBS_init(&hello_verify_request, s->internal->init_msg,
777 	    s->internal->init_num);
778 
779 	if (!CBS_get_u16(&hello_verify_request, &ssl_version))
780 		goto decode_err;
781 	if (!CBS_get_u8_length_prefixed(&hello_verify_request, &cookie))
782 		goto decode_err;
783 	if (CBS_len(&hello_verify_request) != 0)
784 		goto decode_err;
785 
786 	/*
787 	 * Per RFC 6347 section 4.2.1, the HelloVerifyRequest should always
788 	 * contain DTLSv1.0 the version that is going to be negotiated.
789 	 * Tolerate DTLSv1.2 just in case.
790 	 */
791 	if (ssl_version != DTLS1_VERSION && ssl_version != DTLS1_2_VERSION) {
792 		SSLerror(s, SSL_R_WRONG_SSL_VERSION);
793 		s->version = (s->version & 0xff00) | (ssl_version & 0xff);
794 		al = SSL_AD_PROTOCOL_VERSION;
795 		goto fatal_err;
796 	}
797 
798 	if (!CBS_write_bytes(&cookie, s->d1->cookie,
799 	    sizeof(s->d1->cookie), &cookie_len)) {
800 		s->d1->cookie_len = 0;
801 		al = SSL_AD_ILLEGAL_PARAMETER;
802 		goto fatal_err;
803 	}
804 	s->d1->cookie_len = cookie_len;
805 	s->d1->send_cookie = 1;
806 
807 	return 1;
808 
809  decode_err:
810 	al = SSL_AD_DECODE_ERROR;
811  fatal_err:
812 	ssl3_send_alert(s, SSL3_AL_FATAL, al);
813 	return -1;
814 }
815 
816 int
817 ssl3_get_server_hello(SSL *s)
818 {
819 	CBS cbs, server_random, session_id;
820 	uint16_t server_version, cipher_suite;
821 	uint8_t compression_method;
822 	const SSL_CIPHER *cipher;
823 	const SSL_METHOD *method;
824 	unsigned long alg_k;
825 	int al, ret;
826 
827 	s->internal->first_packet = 1;
828 	if ((ret = ssl3_get_message(s, SSL3_ST_CR_SRVR_HELLO_A,
829 	    SSL3_ST_CR_SRVR_HELLO_B, -1, 20000 /* ?? */)) <= 0)
830 		return ret;
831 	s->internal->first_packet = 0;
832 
833 	if (s->internal->init_num < 0)
834 		goto decode_err;
835 
836 	CBS_init(&cbs, s->internal->init_msg, s->internal->init_num);
837 
838 	if (SSL_is_dtls(s)) {
839 		if (s->s3->hs.tls12.message_type == DTLS1_MT_HELLO_VERIFY_REQUEST) {
840 			if (s->d1->send_cookie == 0) {
841 				s->s3->hs.tls12.reuse_message = 1;
842 				return (1);
843 			} else {
844 				/* Already sent a cookie. */
845 				al = SSL_AD_UNEXPECTED_MESSAGE;
846 				SSLerror(s, SSL_R_BAD_MESSAGE_TYPE);
847 				goto fatal_err;
848 			}
849 		}
850 	}
851 
852 	if (s->s3->hs.tls12.message_type != SSL3_MT_SERVER_HELLO) {
853 		al = SSL_AD_UNEXPECTED_MESSAGE;
854 		SSLerror(s, SSL_R_BAD_MESSAGE_TYPE);
855 		goto fatal_err;
856 	}
857 
858 	if (!CBS_get_u16(&cbs, &server_version))
859 		goto decode_err;
860 
861 	if (!ssl_check_version_from_server(s, server_version)) {
862 		SSLerror(s, SSL_R_WRONG_SSL_VERSION);
863 		s->version = (s->version & 0xff00) | (server_version & 0xff);
864 		al = SSL_AD_PROTOCOL_VERSION;
865 		goto fatal_err;
866 	}
867 	s->s3->hs.peer_legacy_version = server_version;
868 	s->version = server_version;
869 
870 	s->s3->hs.negotiated_tls_version = ssl_tls_version(server_version);
871 	if (s->s3->hs.negotiated_tls_version == 0) {
872 		SSLerror(s, ERR_R_INTERNAL_ERROR);
873 		goto err;
874 	}
875 
876 	if ((method = ssl_get_method(server_version)) == NULL) {
877 		SSLerror(s, ERR_R_INTERNAL_ERROR);
878 		goto err;
879 	}
880 	s->method = method;
881 
882 	/* Server random. */
883 	if (!CBS_get_bytes(&cbs, &server_random, SSL3_RANDOM_SIZE))
884 		goto decode_err;
885 	if (!CBS_write_bytes(&server_random, s->s3->server_random,
886 	    sizeof(s->s3->server_random), NULL))
887 		goto err;
888 
889 	if (s->s3->hs.our_max_tls_version >= TLS1_2_VERSION &&
890 	    s->s3->hs.negotiated_tls_version < s->s3->hs.our_max_tls_version) {
891 		/*
892 		 * RFC 8446 section 4.1.3. We must not downgrade if the server
893 		 * random value contains the TLS 1.2 or TLS 1.1 magical value.
894 		 */
895 		if (!CBS_skip(&server_random,
896 		    CBS_len(&server_random) - sizeof(tls13_downgrade_12)))
897 			goto err;
898 		if (s->s3->hs.negotiated_tls_version == TLS1_2_VERSION &&
899 		    CBS_mem_equal(&server_random, tls13_downgrade_12,
900 		    sizeof(tls13_downgrade_12))) {
901 			al = SSL_AD_ILLEGAL_PARAMETER;
902 			SSLerror(s, SSL_R_INAPPROPRIATE_FALLBACK);
903 			goto fatal_err;
904 		}
905 		if (CBS_mem_equal(&server_random, tls13_downgrade_11,
906 		    sizeof(tls13_downgrade_11))) {
907 			al = SSL_AD_ILLEGAL_PARAMETER;
908 			SSLerror(s, SSL_R_INAPPROPRIATE_FALLBACK);
909 			goto fatal_err;
910 		}
911 	}
912 
913 	/* Session ID. */
914 	if (!CBS_get_u8_length_prefixed(&cbs, &session_id))
915 		goto decode_err;
916 
917 	if (CBS_len(&session_id) > SSL3_SESSION_ID_SIZE) {
918 		al = SSL_AD_ILLEGAL_PARAMETER;
919 		SSLerror(s, SSL_R_SSL3_SESSION_ID_TOO_LONG);
920 		goto fatal_err;
921 	}
922 
923 	/* Cipher suite. */
924 	if (!CBS_get_u16(&cbs, &cipher_suite))
925 		goto decode_err;
926 
927 	/*
928 	 * Check if we want to resume the session based on external
929 	 * pre-shared secret.
930 	 */
931 	if (s->internal->tls_session_secret_cb != NULL) {
932 		SSL_CIPHER *pref_cipher = NULL;
933 		int master_key_length = sizeof(s->session->master_key);
934 
935 		if (!s->internal->tls_session_secret_cb(s,
936 		    s->session->master_key, &master_key_length, NULL,
937 		    &pref_cipher, s->internal->tls_session_secret_cb_arg)) {
938 			SSLerror(s, ERR_R_INTERNAL_ERROR);
939 			goto err;
940 		}
941 		if (master_key_length <= 0) {
942 			SSLerror(s, ERR_R_INTERNAL_ERROR);
943 			goto err;
944 		}
945 		s->session->master_key_length = master_key_length;
946 
947 		if ((s->session->cipher = pref_cipher) == NULL)
948 			s->session->cipher =
949 			    ssl3_get_cipher_by_value(cipher_suite);
950 		s->s3->flags |= SSL3_FLAGS_CCS_OK;
951 	}
952 
953 	if (s->session->session_id_length != 0 &&
954 	    CBS_mem_equal(&session_id, s->session->session_id,
955 		s->session->session_id_length)) {
956 		if (s->sid_ctx_length != s->session->sid_ctx_length ||
957 		    timingsafe_memcmp(s->session->sid_ctx,
958 		    s->sid_ctx, s->sid_ctx_length) != 0) {
959 			/* actually a client application bug */
960 			al = SSL_AD_ILLEGAL_PARAMETER;
961 			SSLerror(s, SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT);
962 			goto fatal_err;
963 		}
964 		s->s3->flags |= SSL3_FLAGS_CCS_OK;
965 		s->internal->hit = 1;
966 	} else {
967 		/* a miss or crap from the other end */
968 
969 		/* If we were trying for session-id reuse, make a new
970 		 * SSL_SESSION so we don't stuff up other people */
971 		s->internal->hit = 0;
972 		if (s->session->session_id_length > 0) {
973 			if (!ssl_get_new_session(s, 0)) {
974 				al = SSL_AD_INTERNAL_ERROR;
975 				goto fatal_err;
976 			}
977 		}
978 
979 		/*
980 		 * XXX - improve the handling for the case where there is a
981 		 * zero length session identifier.
982 		 */
983 		if (!CBS_write_bytes(&session_id, s->session->session_id,
984 		    sizeof(s->session->session_id),
985 		    &s->session->session_id_length))
986 			goto err;
987 
988 		s->session->ssl_version = s->version;
989 	}
990 
991 	if ((cipher = ssl3_get_cipher_by_value(cipher_suite)) == NULL) {
992 		al = SSL_AD_ILLEGAL_PARAMETER;
993 		SSLerror(s, SSL_R_UNKNOWN_CIPHER_RETURNED);
994 		goto fatal_err;
995 	}
996 
997 	/* TLS v1.2 only ciphersuites require v1.2 or later. */
998 	if ((cipher->algorithm_ssl & SSL_TLSV1_2) &&
999 	    s->s3->hs.negotiated_tls_version < TLS1_2_VERSION) {
1000 		al = SSL_AD_ILLEGAL_PARAMETER;
1001 		SSLerror(s, SSL_R_WRONG_CIPHER_RETURNED);
1002 		goto fatal_err;
1003 	}
1004 
1005 	if (!ssl_cipher_in_list(SSL_get_ciphers(s), cipher)) {
1006 		/* we did not say we would use this cipher */
1007 		al = SSL_AD_ILLEGAL_PARAMETER;
1008 		SSLerror(s, SSL_R_WRONG_CIPHER_RETURNED);
1009 		goto fatal_err;
1010 	}
1011 
1012 	/*
1013 	 * Depending on the session caching (internal/external), the cipher
1014 	 * and/or cipher_id values may not be set. Make sure that
1015 	 * cipher_id is set and use it for comparison.
1016 	 */
1017 	if (s->session->cipher)
1018 		s->session->cipher_id = s->session->cipher->id;
1019 	if (s->internal->hit && (s->session->cipher_id != cipher->id)) {
1020 		al = SSL_AD_ILLEGAL_PARAMETER;
1021 		SSLerror(s, SSL_R_OLD_SESSION_CIPHER_NOT_RETURNED);
1022 		goto fatal_err;
1023 	}
1024 	s->s3->hs.cipher = cipher;
1025 
1026 	if (!tls1_transcript_hash_init(s))
1027 		goto err;
1028 
1029 	/*
1030 	 * Don't digest cached records if no sigalgs: we may need them for
1031 	 * client authentication.
1032 	 */
1033 	alg_k = s->s3->hs.cipher->algorithm_mkey;
1034 	if (!(SSL_USE_SIGALGS(s) || (alg_k & SSL_kGOST)))
1035 		tls1_transcript_free(s);
1036 
1037 	if (!CBS_get_u8(&cbs, &compression_method))
1038 		goto decode_err;
1039 
1040 	if (compression_method != 0) {
1041 		al = SSL_AD_ILLEGAL_PARAMETER;
1042 		SSLerror(s, SSL_R_UNSUPPORTED_COMPRESSION_ALGORITHM);
1043 		goto fatal_err;
1044 	}
1045 
1046 	if (!tlsext_client_parse(s, SSL_TLSEXT_MSG_SH, &cbs, &al)) {
1047 		SSLerror(s, SSL_R_PARSE_TLSEXT);
1048 		goto fatal_err;
1049 	}
1050 
1051 	if (CBS_len(&cbs) != 0)
1052 		goto decode_err;
1053 
1054 	/*
1055 	 * Determine if we need to see RI. Strictly speaking if we want to
1056 	 * avoid an attack we should *always* see RI even on initial server
1057 	 * hello because the client doesn't see any renegotiation during an
1058 	 * attack. However this would mean we could not connect to any server
1059 	 * which doesn't support RI so for the immediate future tolerate RI
1060 	 * absence on initial connect only.
1061 	 */
1062 	if (!s->s3->renegotiate_seen &&
1063 	    !(s->internal->options & SSL_OP_LEGACY_SERVER_CONNECT)) {
1064 		al = SSL_AD_HANDSHAKE_FAILURE;
1065 		SSLerror(s, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
1066 		goto fatal_err;
1067 	}
1068 
1069 	if (ssl_check_serverhello_tlsext(s) <= 0) {
1070 		SSLerror(s, SSL_R_SERVERHELLO_TLSEXT);
1071 		goto err;
1072 	}
1073 
1074 	return (1);
1075 
1076  decode_err:
1077 	/* wrong packet length */
1078 	al = SSL_AD_DECODE_ERROR;
1079 	SSLerror(s, SSL_R_BAD_PACKET_LENGTH);
1080  fatal_err:
1081 	ssl3_send_alert(s, SSL3_AL_FATAL, al);
1082  err:
1083 	return (-1);
1084 }
1085 
1086 int
1087 ssl3_get_server_certificate(SSL *s)
1088 {
1089 	CBS cbs, cert_list, cert_data;
1090 	STACK_OF(X509) *certs = NULL;
1091 	X509 *cert = NULL;
1092 	const uint8_t *p;
1093 	EVP_PKEY *pkey;
1094 	int cert_type;
1095 	int al, ret;
1096 
1097 	if ((ret = ssl3_get_message(s, SSL3_ST_CR_CERT_A,
1098 	    SSL3_ST_CR_CERT_B, -1, s->internal->max_cert_list)) <= 0)
1099 		return ret;
1100 
1101 	ret = -1;
1102 
1103 	if (s->s3->hs.tls12.message_type == SSL3_MT_SERVER_KEY_EXCHANGE) {
1104 		s->s3->hs.tls12.reuse_message = 1;
1105 		return (1);
1106 	}
1107 
1108 	if (s->s3->hs.tls12.message_type != SSL3_MT_CERTIFICATE) {
1109 		al = SSL_AD_UNEXPECTED_MESSAGE;
1110 		SSLerror(s, SSL_R_BAD_MESSAGE_TYPE);
1111 		goto fatal_err;
1112 	}
1113 
1114 	if ((certs = sk_X509_new_null()) == NULL) {
1115 		SSLerror(s, ERR_R_MALLOC_FAILURE);
1116 		goto err;
1117 	}
1118 
1119 	if (s->internal->init_num < 0)
1120 		goto decode_err;
1121 
1122 	CBS_init(&cbs, s->internal->init_msg, s->internal->init_num);
1123 
1124 	if (!CBS_get_u24_length_prefixed(&cbs, &cert_list))
1125 		goto decode_err;
1126 	if (CBS_len(&cbs) != 0)
1127 		goto decode_err;
1128 
1129 	while (CBS_len(&cert_list) > 0) {
1130 		if (!CBS_get_u24_length_prefixed(&cert_list, &cert_data))
1131 			goto decode_err;
1132 		p = CBS_data(&cert_data);
1133 		if ((cert = d2i_X509(NULL, &p, CBS_len(&cert_data))) == NULL) {
1134 			al = SSL_AD_BAD_CERTIFICATE;
1135 			SSLerror(s, ERR_R_ASN1_LIB);
1136 			goto fatal_err;
1137 		}
1138 		if (p != CBS_data(&cert_data) + CBS_len(&cert_data))
1139 			goto decode_err;
1140 		if (!sk_X509_push(certs, cert)) {
1141 			SSLerror(s, ERR_R_MALLOC_FAILURE);
1142 			goto err;
1143 		}
1144 		cert = NULL;
1145 	}
1146 
1147 	/* A server must always provide a non-empty certificate list. */
1148 	if (sk_X509_num(certs) < 1) {
1149 		SSLerror(s, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE);
1150 		goto decode_err;
1151 	}
1152 
1153 	if (ssl_verify_cert_chain(s, certs) <= 0 &&
1154 	    s->verify_mode != SSL_VERIFY_NONE) {
1155 		al = ssl_verify_alarm_type(s->verify_result);
1156 		SSLerror(s, SSL_R_CERTIFICATE_VERIFY_FAILED);
1157 		goto fatal_err;
1158 	}
1159 	ERR_clear_error(); /* but we keep s->verify_result */
1160 
1161 	/*
1162 	 * Inconsistency alert: cert_chain does include the peer's
1163 	 * certificate, which we don't include in s3_srvr.c
1164 	 */
1165 	cert = sk_X509_value(certs, 0);
1166 	X509_up_ref(cert);
1167 
1168 	if ((pkey = X509_get0_pubkey(cert)) == NULL ||
1169 	    EVP_PKEY_missing_parameters(pkey)) {
1170 		al = SSL3_AL_FATAL;
1171 		SSLerror(s, SSL_R_UNABLE_TO_FIND_PUBLIC_KEY_PARAMETERS);
1172 		goto fatal_err;
1173 	}
1174 	if ((cert_type = ssl_cert_type(pkey)) < 0) {
1175 		al = SSL3_AL_FATAL;
1176 		SSLerror(s, SSL_R_UNKNOWN_CERTIFICATE_TYPE);
1177 		goto fatal_err;
1178 	}
1179 
1180 	X509_free(s->session->peer_cert);
1181 	X509_up_ref(cert);
1182 	s->session->peer_cert = cert;
1183 	s->session->peer_cert_type = cert_type;
1184 
1185 	s->session->verify_result = s->verify_result;
1186 
1187 	sk_X509_pop_free(s->session->cert_chain, X509_free);
1188 	s->session->cert_chain = certs;
1189 	certs = NULL;
1190 
1191 	ret = 1;
1192 
1193 	if (0) {
1194  decode_err:
1195 		/* wrong packet length */
1196 		al = SSL_AD_DECODE_ERROR;
1197 		SSLerror(s, SSL_R_BAD_PACKET_LENGTH);
1198  fatal_err:
1199 		ssl3_send_alert(s, SSL3_AL_FATAL, al);
1200 	}
1201  err:
1202 	sk_X509_pop_free(certs, X509_free);
1203 	X509_free(cert);
1204 
1205 	return (ret);
1206 }
1207 
1208 static int
1209 ssl3_get_server_kex_dhe(SSL *s, CBS *cbs)
1210 {
1211 	int decode_error, invalid_params, invalid_key;
1212 	int nid = NID_dhKeyAgreement;
1213 
1214 	tls_key_share_free(s->s3->hs.key_share);
1215 	if ((s->s3->hs.key_share = tls_key_share_new_nid(nid)) == NULL)
1216 		goto err;
1217 
1218 	if (!tls_key_share_peer_params(s->s3->hs.key_share, cbs,
1219 	    &decode_error, &invalid_params)) {
1220 		if (decode_error) {
1221 			SSLerror(s, SSL_R_BAD_PACKET_LENGTH);
1222 			ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1223 		}
1224 		goto err;
1225 	}
1226 	if (!tls_key_share_peer_public(s->s3->hs.key_share, cbs,
1227 	    &decode_error, &invalid_key)) {
1228 		if (decode_error) {
1229 			SSLerror(s, SSL_R_BAD_PACKET_LENGTH);
1230 			ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1231 		}
1232 		goto err;
1233 	}
1234 
1235 	if (invalid_params) {
1236 		SSLerror(s, SSL_R_BAD_DH_P_LENGTH);
1237 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
1238 		goto err;
1239 	}
1240 	if (invalid_key) {
1241 		SSLerror(s, SSL_R_BAD_DH_PUB_KEY_LENGTH);
1242 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
1243 		goto err;
1244 	}
1245 
1246 	if (!tls_key_share_peer_security(s, s->s3->hs.key_share)) {
1247 		SSLerror(s, SSL_R_DH_KEY_TOO_SMALL);
1248 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
1249 		return 0;
1250 	}
1251 
1252 	return 1;
1253 
1254  err:
1255 	return 0;
1256 }
1257 
1258 static int
1259 ssl3_get_server_kex_ecdhe(SSL *s, CBS *cbs)
1260 {
1261 	uint8_t curve_type;
1262 	uint16_t group_id;
1263 	int decode_error;
1264 	CBS public;
1265 
1266 	if (!CBS_get_u8(cbs, &curve_type))
1267 		goto decode_err;
1268 	if (!CBS_get_u16(cbs, &group_id))
1269 		goto decode_err;
1270 
1271 	/* Only named curves are supported. */
1272 	if (curve_type != NAMED_CURVE_TYPE) {
1273 		SSLerror(s, SSL_R_UNSUPPORTED_ELLIPTIC_CURVE);
1274 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
1275 		goto err;
1276 	}
1277 
1278 	if (!CBS_get_u8_length_prefixed(cbs, &public))
1279 		goto decode_err;
1280 
1281 	/*
1282 	 * Check that the group is one of our preferences - if it is not,
1283 	 * the server has sent us an invalid group.
1284 	 */
1285 	if (!tls1_check_group(s, group_id)) {
1286 		SSLerror(s, SSL_R_WRONG_CURVE);
1287 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
1288 		goto err;
1289 	}
1290 
1291 	tls_key_share_free(s->s3->hs.key_share);
1292 	if ((s->s3->hs.key_share = tls_key_share_new(group_id)) == NULL)
1293 		goto err;
1294 
1295 	if (!tls_key_share_peer_public(s->s3->hs.key_share, &public,
1296 	    &decode_error, NULL)) {
1297 		if (decode_error)
1298 			goto decode_err;
1299 		goto err;
1300 	}
1301 
1302 	return 1;
1303 
1304  decode_err:
1305 	SSLerror(s, SSL_R_BAD_PACKET_LENGTH);
1306 	ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1307  err:
1308 	return 0;
1309 }
1310 
1311 int
1312 ssl3_get_server_key_exchange(SSL *s)
1313 {
1314 	CBS cbs, signature;
1315 	EVP_MD_CTX *md_ctx;
1316 	const unsigned char *param;
1317 	size_t param_len;
1318 	long alg_k, alg_a;
1319 	int al, ret;
1320 
1321 	alg_k = s->s3->hs.cipher->algorithm_mkey;
1322 	alg_a = s->s3->hs.cipher->algorithm_auth;
1323 
1324 	/*
1325 	 * Use same message size as in ssl3_get_certificate_request()
1326 	 * as ServerKeyExchange message may be skipped.
1327 	 */
1328 	if ((ret = ssl3_get_message(s, SSL3_ST_CR_KEY_EXCH_A,
1329 	    SSL3_ST_CR_KEY_EXCH_B, -1, s->internal->max_cert_list)) <= 0)
1330 		return ret;
1331 
1332 	if ((md_ctx = EVP_MD_CTX_new()) == NULL)
1333 		goto err;
1334 
1335 	if (s->internal->init_num < 0)
1336 		goto err;
1337 
1338 	CBS_init(&cbs, s->internal->init_msg, s->internal->init_num);
1339 
1340 	if (s->s3->hs.tls12.message_type != SSL3_MT_SERVER_KEY_EXCHANGE) {
1341 		/*
1342 		 * Do not skip server key exchange if this cipher suite uses
1343 		 * ephemeral keys.
1344 		 */
1345 		if (alg_k & (SSL_kDHE|SSL_kECDHE)) {
1346 			SSLerror(s, SSL_R_UNEXPECTED_MESSAGE);
1347 			al = SSL_AD_UNEXPECTED_MESSAGE;
1348 			goto fatal_err;
1349 		}
1350 
1351 		s->s3->hs.tls12.reuse_message = 1;
1352 		EVP_MD_CTX_free(md_ctx);
1353 		return (1);
1354 	}
1355 
1356 	param = CBS_data(&cbs);
1357 	param_len = CBS_len(&cbs);
1358 
1359 	if (alg_k & SSL_kDHE) {
1360 		if (!ssl3_get_server_kex_dhe(s, &cbs))
1361 			goto err;
1362 	} else if (alg_k & SSL_kECDHE) {
1363 		if (!ssl3_get_server_kex_ecdhe(s, &cbs))
1364 			goto err;
1365 	} else if (alg_k != 0) {
1366 		al = SSL_AD_UNEXPECTED_MESSAGE;
1367 		SSLerror(s, SSL_R_UNEXPECTED_MESSAGE);
1368 		goto fatal_err;
1369 	}
1370 
1371 	param_len -= CBS_len(&cbs);
1372 
1373 	/* if it was signed, check the signature */
1374 	if ((alg_a & SSL_aNULL) == 0) {
1375 		uint16_t sigalg_value = SIGALG_NONE;
1376 		const struct ssl_sigalg *sigalg;
1377 		EVP_PKEY_CTX *pctx;
1378 		EVP_PKEY *pkey = NULL;
1379 
1380 		if ((alg_a & SSL_aRSA) != 0 &&
1381 		    s->session->peer_cert_type == SSL_PKEY_RSA) {
1382 			pkey = X509_get0_pubkey(s->session->peer_cert);
1383 		} else if ((alg_a & SSL_aECDSA) != 0 &&
1384 		    s->session->peer_cert_type == SSL_PKEY_ECC) {
1385 			pkey = X509_get0_pubkey(s->session->peer_cert);
1386 		}
1387 		if (pkey == NULL) {
1388 			al = SSL_AD_ILLEGAL_PARAMETER;
1389 			SSLerror(s, SSL_R_UNKNOWN_CERTIFICATE_TYPE);
1390 			goto fatal_err;
1391 		}
1392 
1393 		if (SSL_USE_SIGALGS(s)) {
1394 			if (!CBS_get_u16(&cbs, &sigalg_value))
1395 				goto decode_err;
1396 		}
1397 		if (!CBS_get_u16_length_prefixed(&cbs, &signature))
1398 			goto decode_err;
1399 		if (CBS_len(&signature) > EVP_PKEY_size(pkey)) {
1400 			al = SSL_AD_DECODE_ERROR;
1401 			SSLerror(s, SSL_R_WRONG_SIGNATURE_LENGTH);
1402 			goto fatal_err;
1403 		}
1404 
1405 		if ((sigalg = ssl_sigalg_for_peer(s, pkey,
1406 		    sigalg_value)) == NULL) {
1407 			al = SSL_AD_DECODE_ERROR;
1408 			goto fatal_err;
1409 		}
1410 		s->s3->hs.peer_sigalg = sigalg;
1411 
1412 		if (!EVP_DigestVerifyInit(md_ctx, &pctx, sigalg->md(),
1413 		    NULL, pkey))
1414 			goto err;
1415 		if (!EVP_DigestVerifyUpdate(md_ctx, s->s3->client_random,
1416 		    SSL3_RANDOM_SIZE))
1417 			goto err;
1418 		if ((sigalg->flags & SIGALG_FLAG_RSA_PSS) &&
1419 		    (!EVP_PKEY_CTX_set_rsa_padding(pctx,
1420 		    RSA_PKCS1_PSS_PADDING) ||
1421 		    !EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, -1)))
1422 			goto err;
1423 		if (!EVP_DigestVerifyUpdate(md_ctx, s->s3->server_random,
1424 		    SSL3_RANDOM_SIZE))
1425 			goto err;
1426 		if (!EVP_DigestVerifyUpdate(md_ctx, param, param_len))
1427 			goto err;
1428 		if (EVP_DigestVerifyFinal(md_ctx, CBS_data(&signature),
1429 		    CBS_len(&signature)) <= 0) {
1430 			al = SSL_AD_DECRYPT_ERROR;
1431 			SSLerror(s, SSL_R_BAD_SIGNATURE);
1432 			goto fatal_err;
1433 		}
1434 	}
1435 
1436 	if (CBS_len(&cbs) != 0) {
1437 		al = SSL_AD_DECODE_ERROR;
1438 		SSLerror(s, SSL_R_EXTRA_DATA_IN_MESSAGE);
1439 		goto fatal_err;
1440 	}
1441 
1442 	EVP_MD_CTX_free(md_ctx);
1443 
1444 	return (1);
1445 
1446  decode_err:
1447 	al = SSL_AD_DECODE_ERROR;
1448 	SSLerror(s, SSL_R_BAD_PACKET_LENGTH);
1449 
1450  fatal_err:
1451 	ssl3_send_alert(s, SSL3_AL_FATAL, al);
1452 
1453  err:
1454 	EVP_MD_CTX_free(md_ctx);
1455 
1456 	return (-1);
1457 }
1458 
1459 int
1460 ssl3_get_certificate_request(SSL *s)
1461 {
1462 	CBS cert_request, cert_types, rdn_list;
1463 	X509_NAME *xn = NULL;
1464 	const unsigned char *q;
1465 	STACK_OF(X509_NAME) *ca_sk = NULL;
1466 	int ret;
1467 
1468 	if ((ret = ssl3_get_message(s, SSL3_ST_CR_CERT_REQ_A,
1469 	    SSL3_ST_CR_CERT_REQ_B, -1, s->internal->max_cert_list)) <= 0)
1470 		return ret;
1471 
1472 	ret = 0;
1473 
1474 	s->s3->hs.tls12.cert_request = 0;
1475 
1476 	if (s->s3->hs.tls12.message_type == SSL3_MT_SERVER_DONE) {
1477 		s->s3->hs.tls12.reuse_message = 1;
1478 		/*
1479 		 * If we get here we don't need any cached handshake records
1480 		 * as we wont be doing client auth.
1481 		 */
1482 		tls1_transcript_free(s);
1483 		return (1);
1484 	}
1485 
1486 	if (s->s3->hs.tls12.message_type != SSL3_MT_CERTIFICATE_REQUEST) {
1487 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
1488 		SSLerror(s, SSL_R_WRONG_MESSAGE_TYPE);
1489 		goto err;
1490 	}
1491 
1492 	/* TLS does not like anon-DH with client cert */
1493 	if (s->s3->hs.cipher->algorithm_auth & SSL_aNULL) {
1494 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
1495 		SSLerror(s, SSL_R_TLS_CLIENT_CERT_REQ_WITH_ANON_CIPHER);
1496 		goto err;
1497 	}
1498 
1499 	if (s->internal->init_num < 0)
1500 		goto decode_err;
1501 	CBS_init(&cert_request, s->internal->init_msg, s->internal->init_num);
1502 
1503 	if ((ca_sk = sk_X509_NAME_new(ca_dn_cmp)) == NULL) {
1504 		SSLerror(s, ERR_R_MALLOC_FAILURE);
1505 		goto err;
1506 	}
1507 
1508 	if (!CBS_get_u8_length_prefixed(&cert_request, &cert_types))
1509 		goto decode_err;
1510 
1511 	if (SSL_USE_SIGALGS(s)) {
1512 		CBS sigalgs;
1513 
1514 		if (CBS_len(&cert_request) < 2) {
1515 			SSLerror(s, SSL_R_DATA_LENGTH_TOO_LONG);
1516 			goto err;
1517 		}
1518 		if (!CBS_get_u16_length_prefixed(&cert_request, &sigalgs)) {
1519 			ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1520 			SSLerror(s, SSL_R_DATA_LENGTH_TOO_LONG);
1521 			goto err;
1522 		}
1523 		if (CBS_len(&sigalgs) % 2 != 0 || CBS_len(&sigalgs) > 64) {
1524 			ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1525 			SSLerror(s, SSL_R_SIGNATURE_ALGORITHMS_ERROR);
1526 			goto err;
1527 		}
1528 		if (!CBS_stow(&sigalgs, &s->s3->hs.sigalgs,
1529 		    &s->s3->hs.sigalgs_len))
1530 			goto err;
1531 	}
1532 
1533 	/* get the CA RDNs */
1534 	if (CBS_len(&cert_request) < 2) {
1535 		SSLerror(s, SSL_R_DATA_LENGTH_TOO_LONG);
1536 		goto err;
1537 	}
1538 
1539 	if (!CBS_get_u16_length_prefixed(&cert_request, &rdn_list) ||
1540 	    CBS_len(&cert_request) != 0) {
1541 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1542 		SSLerror(s, SSL_R_LENGTH_MISMATCH);
1543 		goto err;
1544 	}
1545 
1546 	while (CBS_len(&rdn_list) > 0) {
1547 		CBS rdn;
1548 
1549 		if (CBS_len(&rdn_list) < 2) {
1550 			SSLerror(s, SSL_R_DATA_LENGTH_TOO_LONG);
1551 			goto err;
1552 		}
1553 
1554 		if (!CBS_get_u16_length_prefixed(&rdn_list, &rdn)) {
1555 			ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1556 			SSLerror(s, SSL_R_CA_DN_TOO_LONG);
1557 			goto err;
1558 		}
1559 
1560 		q = CBS_data(&rdn);
1561 		if ((xn = d2i_X509_NAME(NULL, &q, CBS_len(&rdn))) == NULL) {
1562 			ssl3_send_alert(s, SSL3_AL_FATAL,
1563 			    SSL_AD_DECODE_ERROR);
1564 			SSLerror(s, ERR_R_ASN1_LIB);
1565 			goto err;
1566 		}
1567 
1568 		if (q != CBS_data(&rdn) + CBS_len(&rdn)) {
1569 			ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1570 			SSLerror(s, SSL_R_CA_DN_LENGTH_MISMATCH);
1571 			goto err;
1572 		}
1573 		if (!sk_X509_NAME_push(ca_sk, xn)) {
1574 			SSLerror(s, ERR_R_MALLOC_FAILURE);
1575 			goto err;
1576 		}
1577 		xn = NULL;	/* avoid free in err block */
1578 	}
1579 
1580 	/* we should setup a certificate to return.... */
1581 	s->s3->hs.tls12.cert_request = 1;
1582 	sk_X509_NAME_pop_free(s->s3->hs.tls12.ca_names, X509_NAME_free);
1583 	s->s3->hs.tls12.ca_names = ca_sk;
1584 	ca_sk = NULL;
1585 
1586 	ret = 1;
1587 	if (0) {
1588  decode_err:
1589 		SSLerror(s, SSL_R_BAD_PACKET_LENGTH);
1590 	}
1591  err:
1592 	X509_NAME_free(xn);
1593 	sk_X509_NAME_pop_free(ca_sk, X509_NAME_free);
1594 	return (ret);
1595 }
1596 
1597 static int
1598 ca_dn_cmp(const X509_NAME * const *a, const X509_NAME * const *b)
1599 {
1600 	return (X509_NAME_cmp(*a, *b));
1601 }
1602 
1603 int
1604 ssl3_get_new_session_ticket(SSL *s)
1605 {
1606 	uint32_t lifetime_hint;
1607 	CBS cbs, session_ticket;
1608 	unsigned int session_id_length = 0;
1609 	int al, ret;
1610 
1611 	if ((ret = ssl3_get_message(s, SSL3_ST_CR_SESSION_TICKET_A,
1612 	    SSL3_ST_CR_SESSION_TICKET_B, -1, 16384)) <= 0)
1613 		return ret;
1614 
1615 	if (s->s3->hs.tls12.message_type == SSL3_MT_FINISHED) {
1616 		s->s3->hs.tls12.reuse_message = 1;
1617 		return (1);
1618 	}
1619 	if (s->s3->hs.tls12.message_type != SSL3_MT_NEWSESSION_TICKET) {
1620 		al = SSL_AD_UNEXPECTED_MESSAGE;
1621 		SSLerror(s, SSL_R_BAD_MESSAGE_TYPE);
1622 		goto fatal_err;
1623 	}
1624 
1625 	if (s->internal->init_num < 0) {
1626 		al = SSL_AD_DECODE_ERROR;
1627 		SSLerror(s, SSL_R_LENGTH_MISMATCH);
1628 		goto fatal_err;
1629 	}
1630 
1631 	CBS_init(&cbs, s->internal->init_msg, s->internal->init_num);
1632 	if (!CBS_get_u32(&cbs, &lifetime_hint) ||
1633 	    !CBS_get_u16_length_prefixed(&cbs, &session_ticket) ||
1634 	    CBS_len(&cbs) != 0) {
1635 		al = SSL_AD_DECODE_ERROR;
1636 		SSLerror(s, SSL_R_LENGTH_MISMATCH);
1637 		goto fatal_err;
1638 	}
1639 	s->session->tlsext_tick_lifetime_hint = lifetime_hint;
1640 
1641 	if (!CBS_stow(&session_ticket, &s->session->tlsext_tick,
1642 	    &s->session->tlsext_ticklen)) {
1643 		SSLerror(s, ERR_R_MALLOC_FAILURE);
1644 		goto err;
1645 	}
1646 
1647 	/*
1648 	 * There are two ways to detect a resumed ticket sesion.
1649 	 * One is to set an appropriate session ID and then the server
1650 	 * must return a match in ServerHello. This allows the normal
1651 	 * client session ID matching to work and we know much
1652 	 * earlier that the ticket has been accepted.
1653 	 *
1654 	 * The other way is to set zero length session ID when the
1655 	 * ticket is presented and rely on the handshake to determine
1656 	 * session resumption.
1657 	 *
1658 	 * We choose the former approach because this fits in with
1659 	 * assumptions elsewhere in OpenSSL. The session ID is set
1660 	 * to the SHA256 hash of the ticket.
1661 	 */
1662 	if (!EVP_Digest(CBS_data(&session_ticket), CBS_len(&session_ticket),
1663 	    s->session->session_id, &session_id_length, EVP_sha256(), NULL)) {
1664 		al = SSL_AD_INTERNAL_ERROR;
1665 		SSLerror(s, ERR_R_EVP_LIB);
1666 		goto fatal_err;
1667 	}
1668 	s->session->session_id_length = session_id_length;
1669 
1670 	return (1);
1671 
1672  fatal_err:
1673 	ssl3_send_alert(s, SSL3_AL_FATAL, al);
1674  err:
1675 	return (-1);
1676 }
1677 
1678 int
1679 ssl3_get_cert_status(SSL *s)
1680 {
1681 	CBS cert_status, response;
1682 	uint8_t	status_type;
1683 	int al, ret;
1684 
1685 	if ((ret = ssl3_get_message(s, SSL3_ST_CR_CERT_STATUS_A,
1686 	    SSL3_ST_CR_CERT_STATUS_B, -1, 16384)) <= 0)
1687 		return ret;
1688 
1689 	if (s->s3->hs.tls12.message_type == SSL3_MT_SERVER_KEY_EXCHANGE) {
1690 		/*
1691 		 * Tell the callback the server did not send us an OSCP
1692 		 * response, and has decided to head directly to key exchange.
1693 		 */
1694 		if (s->ctx->internal->tlsext_status_cb) {
1695 			free(s->internal->tlsext_ocsp_resp);
1696 			s->internal->tlsext_ocsp_resp = NULL;
1697 			s->internal->tlsext_ocsp_resp_len = 0;
1698 
1699 			ret = s->ctx->internal->tlsext_status_cb(s,
1700 			    s->ctx->internal->tlsext_status_arg);
1701 			if (ret == 0) {
1702 				al = SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE;
1703 				SSLerror(s, SSL_R_INVALID_STATUS_RESPONSE);
1704 				goto fatal_err;
1705 			}
1706 			if (ret < 0) {
1707 				al = SSL_AD_INTERNAL_ERROR;
1708 				SSLerror(s, ERR_R_MALLOC_FAILURE);
1709 				goto fatal_err;
1710 			}
1711 		}
1712 		s->s3->hs.tls12.reuse_message = 1;
1713 		return (1);
1714 	}
1715 
1716 	if (s->s3->hs.tls12.message_type != SSL3_MT_CERTIFICATE &&
1717 	    s->s3->hs.tls12.message_type != SSL3_MT_CERTIFICATE_STATUS) {
1718 		al = SSL_AD_UNEXPECTED_MESSAGE;
1719 		SSLerror(s, SSL_R_BAD_MESSAGE_TYPE);
1720 		goto fatal_err;
1721 	}
1722 
1723 	if (s->internal->init_num < 0) {
1724 		/* need at least status type + length */
1725 		al = SSL_AD_DECODE_ERROR;
1726 		SSLerror(s, SSL_R_LENGTH_MISMATCH);
1727 		goto fatal_err;
1728 	}
1729 
1730 	CBS_init(&cert_status, s->internal->init_msg, s->internal->init_num);
1731 	if (!CBS_get_u8(&cert_status, &status_type) ||
1732 	    CBS_len(&cert_status) < 3) {
1733 		/* need at least status type + length */
1734 		al = SSL_AD_DECODE_ERROR;
1735 		SSLerror(s, SSL_R_LENGTH_MISMATCH);
1736 		goto fatal_err;
1737 	}
1738 
1739 	if (status_type != TLSEXT_STATUSTYPE_ocsp) {
1740 		al = SSL_AD_DECODE_ERROR;
1741 		SSLerror(s, SSL_R_UNSUPPORTED_STATUS_TYPE);
1742 		goto fatal_err;
1743 	}
1744 
1745 	if (!CBS_get_u24_length_prefixed(&cert_status, &response) ||
1746 	    CBS_len(&cert_status) != 0) {
1747 		al = SSL_AD_DECODE_ERROR;
1748 		SSLerror(s, SSL_R_LENGTH_MISMATCH);
1749 		goto fatal_err;
1750 	}
1751 
1752 	if (!CBS_stow(&response, &s->internal->tlsext_ocsp_resp,
1753 	    &s->internal->tlsext_ocsp_resp_len)) {
1754 		al = SSL_AD_INTERNAL_ERROR;
1755 		SSLerror(s, ERR_R_MALLOC_FAILURE);
1756 		goto fatal_err;
1757 	}
1758 
1759 	if (s->ctx->internal->tlsext_status_cb) {
1760 		int ret;
1761 		ret = s->ctx->internal->tlsext_status_cb(s,
1762 		    s->ctx->internal->tlsext_status_arg);
1763 		if (ret == 0) {
1764 			al = SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE;
1765 			SSLerror(s, SSL_R_INVALID_STATUS_RESPONSE);
1766 			goto fatal_err;
1767 		}
1768 		if (ret < 0) {
1769 			al = SSL_AD_INTERNAL_ERROR;
1770 			SSLerror(s, ERR_R_MALLOC_FAILURE);
1771 			goto fatal_err;
1772 		}
1773 	}
1774 	return (1);
1775  fatal_err:
1776 	ssl3_send_alert(s, SSL3_AL_FATAL, al);
1777 	return (-1);
1778 }
1779 
1780 int
1781 ssl3_get_server_done(SSL *s)
1782 {
1783 	int ret;
1784 
1785 	if ((ret = ssl3_get_message(s, SSL3_ST_CR_SRVR_DONE_A,
1786 	    SSL3_ST_CR_SRVR_DONE_B, SSL3_MT_SERVER_DONE,
1787 	    30 /* should be very small, like 0 :-) */)) <= 0)
1788 		return ret;
1789 
1790 	if (s->internal->init_num != 0) {
1791 		/* should contain no data */
1792 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1793 		SSLerror(s, SSL_R_LENGTH_MISMATCH);
1794 		return -1;
1795 	}
1796 
1797 	return 1;
1798 }
1799 
1800 static int
1801 ssl3_send_client_kex_rsa(SSL *s, CBB *cbb)
1802 {
1803 	unsigned char pms[SSL_MAX_MASTER_KEY_LENGTH];
1804 	unsigned char *enc_pms = NULL;
1805 	uint16_t max_legacy_version;
1806 	EVP_PKEY *pkey;
1807 	RSA *rsa;
1808 	int ret = 0;
1809 	int enc_len;
1810 	CBB epms;
1811 
1812 	/*
1813 	 * RSA-Encrypted Premaster Secret Message - RFC 5246 section 7.4.7.1.
1814 	 */
1815 
1816 	pkey = X509_get0_pubkey(s->session->peer_cert);
1817 	if (pkey == NULL || (rsa = EVP_PKEY_get0_RSA(pkey)) == NULL) {
1818 		SSLerror(s, ERR_R_INTERNAL_ERROR);
1819 		goto err;
1820 	}
1821 
1822 	/*
1823 	 * Our maximum legacy protocol version - while RFC 5246 section 7.4.7.1
1824 	 * says "The latest (newest) version supported by the client", if we're
1825 	 * doing RSA key exchange then we have to presume that we're talking to
1826 	 * a server that does not understand the supported versions extension
1827 	 * and therefore our maximum version is that sent in the ClientHello.
1828 	 */
1829 	if (!ssl_max_legacy_version(s, &max_legacy_version))
1830 		goto err;
1831 	pms[0] = max_legacy_version >> 8;
1832 	pms[1] = max_legacy_version & 0xff;
1833 	arc4random_buf(&pms[2], sizeof(pms) - 2);
1834 
1835 	if ((enc_pms = malloc(RSA_size(rsa))) == NULL) {
1836 		SSLerror(s, ERR_R_MALLOC_FAILURE);
1837 		goto err;
1838 	}
1839 
1840 	enc_len = RSA_public_encrypt(sizeof(pms), pms, enc_pms, rsa,
1841 	    RSA_PKCS1_PADDING);
1842 	if (enc_len <= 0) {
1843 		SSLerror(s, SSL_R_BAD_RSA_ENCRYPT);
1844 		goto err;
1845 	}
1846 
1847 	if (!CBB_add_u16_length_prefixed(cbb, &epms))
1848 		goto err;
1849 	if (!CBB_add_bytes(&epms, enc_pms, enc_len))
1850 		goto err;
1851 	if (!CBB_flush(cbb))
1852 		goto err;
1853 
1854 	if (!tls12_derive_master_secret(s, pms, sizeof(pms)))
1855 		goto err;
1856 
1857 	ret = 1;
1858 
1859  err:
1860 	explicit_bzero(pms, sizeof(pms));
1861 	free(enc_pms);
1862 
1863 	return ret;
1864 }
1865 
1866 static int
1867 ssl3_send_client_kex_dhe(SSL *s, CBB *cbb)
1868 {
1869 	uint8_t *key = NULL;
1870 	size_t key_len = 0;
1871 	int ret = 0;
1872 
1873 	/* Ensure that we have an ephemeral key from the server for DHE. */
1874 	if (s->s3->hs.key_share == NULL) {
1875 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
1876 		SSLerror(s, SSL_R_UNABLE_TO_FIND_DH_PARAMETERS);
1877 		goto err;
1878 	}
1879 
1880 	if (!tls_key_share_generate(s->s3->hs.key_share))
1881 		goto err;
1882 	if (!tls_key_share_public(s->s3->hs.key_share, cbb))
1883 		goto err;
1884 	if (!tls_key_share_derive(s->s3->hs.key_share, &key, &key_len))
1885 		goto err;
1886 
1887 	if (!tls_key_share_peer_security(s, s->s3->hs.key_share)) {
1888 		SSLerror(s, SSL_R_DH_KEY_TOO_SMALL);
1889 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
1890 		return 0;
1891 	}
1892 
1893 	if (!tls12_derive_master_secret(s, key, key_len))
1894 		goto err;
1895 
1896 	ret = 1;
1897 
1898  err:
1899 	freezero(key, key_len);
1900 
1901 	return ret;
1902 }
1903 
1904 static int
1905 ssl3_send_client_kex_ecdhe(SSL *s, CBB *cbb)
1906 {
1907 	uint8_t *key = NULL;
1908 	size_t key_len = 0;
1909 	CBB public;
1910 	int ret = 0;
1911 
1912 	/* Ensure that we have an ephemeral key for ECDHE. */
1913 	if (s->s3->hs.key_share == NULL) {
1914 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
1915 		SSLerror(s, ERR_R_INTERNAL_ERROR);
1916 		goto err;
1917 	}
1918 
1919 	if (!tls_key_share_generate(s->s3->hs.key_share))
1920 		goto err;
1921 
1922 	if (!CBB_add_u8_length_prefixed(cbb, &public))
1923 		return 0;
1924 	if (!tls_key_share_public(s->s3->hs.key_share, &public))
1925 		goto err;
1926 	if (!CBB_flush(cbb))
1927 		goto err;
1928 
1929 	if (!tls_key_share_derive(s->s3->hs.key_share, &key, &key_len))
1930 		goto err;
1931 
1932 	if (!tls12_derive_master_secret(s, key, key_len))
1933 		goto err;
1934 
1935 	ret = 1;
1936 
1937  err:
1938 	freezero(key, key_len);
1939 
1940 	return ret;
1941 }
1942 
1943 static int
1944 ssl3_send_client_kex_gost(SSL *s, CBB *cbb)
1945 {
1946 	unsigned char premaster_secret[32], shared_ukm[32], tmp[256];
1947 	EVP_PKEY_CTX *pkey_ctx = NULL;
1948 	EVP_MD_CTX *ukm_hash = NULL;
1949 	EVP_PKEY *pkey;
1950 	size_t msglen;
1951 	unsigned int md_len;
1952 	CBB gostblob;
1953 	int nid;
1954 	int ret = 0;
1955 
1956 	/* Get server sertificate PKEY and create ctx from it */
1957 	pkey = X509_get0_pubkey(s->session->peer_cert);
1958 	if (pkey == NULL || s->session->peer_cert_type != SSL_PKEY_GOST01) {
1959 		SSLerror(s, SSL_R_NO_GOST_CERTIFICATE_SENT_BY_PEER);
1960 		goto err;
1961 	}
1962 	if ((pkey_ctx = EVP_PKEY_CTX_new(pkey, NULL)) == NULL) {
1963 		SSLerror(s, ERR_R_MALLOC_FAILURE);
1964 		goto err;
1965 	}
1966 
1967 	/*
1968 	 * If we have send a certificate, and certificate key parameters match
1969 	 * those of server certificate, use certificate key for key exchange.
1970 	 * Otherwise, generate ephemeral key pair.
1971 	 */
1972 	if (EVP_PKEY_encrypt_init(pkey_ctx) <= 0)
1973 		goto err;
1974 
1975 	/* Generate session key. */
1976 	arc4random_buf(premaster_secret, sizeof(premaster_secret));
1977 
1978 	/*
1979 	 * If we have client certificate, use its secret as peer key.
1980 	 * XXX - this presumably lacks PFS.
1981 	 */
1982 	if (s->s3->hs.tls12.cert_request != 0 &&
1983 	    s->cert->key->privatekey != NULL) {
1984 		if (EVP_PKEY_derive_set_peer(pkey_ctx,
1985 		    s->cert->key->privatekey) <=0) {
1986 			/*
1987 			 * If there was an error - just ignore it.
1988 			 * Ephemeral key would be used.
1989 			 */
1990 			ERR_clear_error();
1991 		}
1992 	}
1993 
1994 	/*
1995 	 * Compute shared IV and store it in algorithm-specific context data.
1996 	 */
1997 	if ((ukm_hash = EVP_MD_CTX_new()) == NULL) {
1998 		SSLerror(s, ERR_R_MALLOC_FAILURE);
1999 		goto err;
2000 	}
2001 
2002 	/* XXX check handshake hash instead. */
2003 	if (s->s3->hs.cipher->algorithm2 & SSL_HANDSHAKE_MAC_GOST94)
2004 		nid = NID_id_GostR3411_94;
2005 	else
2006 		nid = NID_id_tc26_gost3411_2012_256;
2007 	if (!EVP_DigestInit(ukm_hash, EVP_get_digestbynid(nid)))
2008 		goto err;
2009 	if (!EVP_DigestUpdate(ukm_hash, s->s3->client_random, SSL3_RANDOM_SIZE))
2010 		goto err;
2011 	if (!EVP_DigestUpdate(ukm_hash, s->s3->server_random, SSL3_RANDOM_SIZE))
2012 		goto err;
2013 	if (!EVP_DigestFinal_ex(ukm_hash, shared_ukm, &md_len))
2014 		goto err;
2015 	if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, EVP_PKEY_OP_ENCRYPT,
2016 	    EVP_PKEY_CTRL_SET_IV, 8, shared_ukm) < 0) {
2017 		SSLerror(s, SSL_R_LIBRARY_BUG);
2018 		goto err;
2019 	}
2020 
2021 	/*
2022 	 * Make GOST keytransport blob message, encapsulate it into sequence.
2023 	 */
2024 	msglen = 255;
2025 	if (EVP_PKEY_encrypt(pkey_ctx, tmp, &msglen, premaster_secret,
2026 	    sizeof(premaster_secret)) < 0) {
2027 		SSLerror(s, SSL_R_LIBRARY_BUG);
2028 		goto err;
2029 	}
2030 
2031 	if (!CBB_add_asn1(cbb, &gostblob, CBS_ASN1_SEQUENCE))
2032 		goto err;
2033 	if (!CBB_add_bytes(&gostblob, tmp, msglen))
2034 		goto err;
2035 	if (!CBB_flush(cbb))
2036 		goto err;
2037 
2038 	/* Check if pubkey from client certificate was used. */
2039 	if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, -1, EVP_PKEY_CTRL_PEER_KEY, 2,
2040 	    NULL) > 0)
2041 		s->s3->flags |= TLS1_FLAGS_SKIP_CERT_VERIFY;
2042 
2043 	if (!tls12_derive_master_secret(s, premaster_secret, 32))
2044 		goto err;
2045 
2046 	ret = 1;
2047 
2048  err:
2049 	explicit_bzero(premaster_secret, sizeof(premaster_secret));
2050 	EVP_PKEY_CTX_free(pkey_ctx);
2051 	EVP_MD_CTX_free(ukm_hash);
2052 
2053 	return ret;
2054 }
2055 
2056 int
2057 ssl3_send_client_key_exchange(SSL *s)
2058 {
2059 	unsigned long alg_k;
2060 	CBB cbb, kex;
2061 
2062 	memset(&cbb, 0, sizeof(cbb));
2063 
2064 	if (s->s3->hs.state == SSL3_ST_CW_KEY_EXCH_A) {
2065 		alg_k = s->s3->hs.cipher->algorithm_mkey;
2066 
2067 		if (!ssl3_handshake_msg_start(s, &cbb, &kex,
2068 		    SSL3_MT_CLIENT_KEY_EXCHANGE))
2069 			goto err;
2070 
2071 		if (alg_k & SSL_kRSA) {
2072 			if (!ssl3_send_client_kex_rsa(s, &kex))
2073 				goto err;
2074 		} else if (alg_k & SSL_kDHE) {
2075 			if (!ssl3_send_client_kex_dhe(s, &kex))
2076 				goto err;
2077 		} else if (alg_k & SSL_kECDHE) {
2078 			if (!ssl3_send_client_kex_ecdhe(s, &kex))
2079 				goto err;
2080 		} else if (alg_k & SSL_kGOST) {
2081 			if (!ssl3_send_client_kex_gost(s, &kex))
2082 				goto err;
2083 		} else {
2084 			ssl3_send_alert(s, SSL3_AL_FATAL,
2085 			    SSL_AD_HANDSHAKE_FAILURE);
2086 			SSLerror(s, ERR_R_INTERNAL_ERROR);
2087 			goto err;
2088 		}
2089 
2090 		if (!ssl3_handshake_msg_finish(s, &cbb))
2091 			goto err;
2092 
2093 		s->s3->hs.state = SSL3_ST_CW_KEY_EXCH_B;
2094 	}
2095 
2096 	/* SSL3_ST_CW_KEY_EXCH_B */
2097 	return (ssl3_handshake_write(s));
2098 
2099  err:
2100 	CBB_cleanup(&cbb);
2101 
2102 	return (-1);
2103 }
2104 
2105 static int
2106 ssl3_send_client_verify_sigalgs(SSL *s, EVP_PKEY *pkey,
2107     const struct ssl_sigalg *sigalg, CBB *cert_verify)
2108 {
2109 	CBB cbb_signature;
2110 	EVP_PKEY_CTX *pctx = NULL;
2111 	EVP_MD_CTX *mctx = NULL;
2112 	const unsigned char *hdata;
2113 	unsigned char *signature = NULL;
2114 	size_t signature_len, hdata_len;
2115 	int ret = 0;
2116 
2117 	if ((mctx = EVP_MD_CTX_new()) == NULL)
2118 		goto err;
2119 
2120 	if (!tls1_transcript_data(s, &hdata, &hdata_len)) {
2121 		SSLerror(s, ERR_R_INTERNAL_ERROR);
2122 		goto err;
2123 	}
2124 	if (!EVP_DigestSignInit(mctx, &pctx, sigalg->md(), NULL, pkey)) {
2125 		SSLerror(s, ERR_R_EVP_LIB);
2126 		goto err;
2127 	}
2128 	if (sigalg->key_type == EVP_PKEY_GOSTR01 &&
2129 	    EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_SIGN,
2130 	    EVP_PKEY_CTRL_GOST_SIG_FORMAT, GOST_SIG_FORMAT_RS_LE, NULL) <= 0) {
2131 		SSLerror(s, ERR_R_EVP_LIB);
2132 		goto err;
2133 	}
2134 	if ((sigalg->flags & SIGALG_FLAG_RSA_PSS) &&
2135 	    (!EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) ||
2136 	    !EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, -1))) {
2137 		SSLerror(s, ERR_R_EVP_LIB);
2138 		goto err;
2139 	}
2140 	if (!EVP_DigestSignUpdate(mctx, hdata, hdata_len)) {
2141 		SSLerror(s, ERR_R_EVP_LIB);
2142 		goto err;
2143 	}
2144 	if (!EVP_DigestSignFinal(mctx, NULL, &signature_len) ||
2145 	    signature_len == 0) {
2146 		SSLerror(s, ERR_R_EVP_LIB);
2147 		goto err;
2148 	}
2149 	if ((signature = calloc(1, signature_len)) == NULL) {
2150 		SSLerror(s, ERR_R_MALLOC_FAILURE);
2151 		goto err;
2152 	}
2153 	if (!EVP_DigestSignFinal(mctx, signature, &signature_len)) {
2154 		SSLerror(s, ERR_R_EVP_LIB);
2155 		goto err;
2156 	}
2157 
2158 	if (!CBB_add_u16(cert_verify, sigalg->value))
2159 		goto err;
2160 	if (!CBB_add_u16_length_prefixed(cert_verify, &cbb_signature))
2161 		goto err;
2162 	if (!CBB_add_bytes(&cbb_signature, signature, signature_len))
2163 		goto err;
2164 	if (!CBB_flush(cert_verify))
2165 		goto err;
2166 
2167 	ret = 1;
2168 
2169  err:
2170 	EVP_MD_CTX_free(mctx);
2171 	free(signature);
2172 	return ret;
2173 }
2174 
2175 static int
2176 ssl3_send_client_verify_rsa(SSL *s, EVP_PKEY *pkey, CBB *cert_verify)
2177 {
2178 	CBB cbb_signature;
2179 	RSA *rsa;
2180 	unsigned char data[EVP_MAX_MD_SIZE];
2181 	unsigned char *signature = NULL;
2182 	unsigned int signature_len;
2183 	size_t data_len;
2184 	int ret = 0;
2185 
2186 	if (!tls1_transcript_hash_value(s, data, sizeof(data), &data_len))
2187 		goto err;
2188 	if ((signature = calloc(1, EVP_PKEY_size(pkey))) == NULL)
2189 		goto err;
2190 	if ((rsa = EVP_PKEY_get0_RSA(pkey)) == NULL)
2191 		goto err;
2192 	if (RSA_sign(NID_md5_sha1, data, data_len, signature, &signature_len,
2193 	    rsa) <= 0 ) {
2194 		SSLerror(s, ERR_R_RSA_LIB);
2195 		goto err;
2196 	}
2197 
2198 	if (!CBB_add_u16_length_prefixed(cert_verify, &cbb_signature))
2199 		goto err;
2200 	if (!CBB_add_bytes(&cbb_signature, signature, signature_len))
2201 		goto err;
2202 	if (!CBB_flush(cert_verify))
2203 		goto err;
2204 
2205 	ret = 1;
2206  err:
2207 	free(signature);
2208 	return ret;
2209 }
2210 
2211 static int
2212 ssl3_send_client_verify_ec(SSL *s, EVP_PKEY *pkey, CBB *cert_verify)
2213 {
2214 	CBB cbb_signature;
2215 	EC_KEY *eckey;
2216 	unsigned char data[EVP_MAX_MD_SIZE];
2217 	unsigned char *signature = NULL;
2218 	unsigned int signature_len;
2219 	int ret = 0;
2220 
2221 	if (!tls1_transcript_hash_value(s, data, sizeof(data), NULL))
2222 		goto err;
2223 	if ((signature = calloc(1, EVP_PKEY_size(pkey))) == NULL)
2224 		goto err;
2225 	if ((eckey = EVP_PKEY_get0_EC_KEY(pkey)) == NULL)
2226 		goto err;
2227 	if (!ECDSA_sign(0, &data[MD5_DIGEST_LENGTH], SHA_DIGEST_LENGTH,
2228 	    signature, &signature_len, eckey)) {
2229 		SSLerror(s, ERR_R_ECDSA_LIB);
2230 		goto err;
2231 	}
2232 
2233 	if (!CBB_add_u16_length_prefixed(cert_verify, &cbb_signature))
2234 		goto err;
2235 	if (!CBB_add_bytes(&cbb_signature, signature, signature_len))
2236 		goto err;
2237 	if (!CBB_flush(cert_verify))
2238 		goto err;
2239 
2240 	ret = 1;
2241  err:
2242 	free(signature);
2243 	return ret;
2244 }
2245 
2246 #ifndef OPENSSL_NO_GOST
2247 static int
2248 ssl3_send_client_verify_gost(SSL *s, EVP_PKEY *pkey, CBB *cert_verify)
2249 {
2250 	CBB cbb_signature;
2251 	EVP_MD_CTX *mctx;
2252 	EVP_PKEY_CTX *pctx;
2253 	const EVP_MD *md;
2254 	const unsigned char *hdata;
2255 	unsigned char *signature = NULL;
2256 	size_t signature_len;
2257 	size_t hdata_len;
2258 	int nid;
2259 	int ret = 0;
2260 
2261 	if ((mctx = EVP_MD_CTX_new()) == NULL)
2262 		goto err;
2263 
2264 	if (!tls1_transcript_data(s, &hdata, &hdata_len)) {
2265 		SSLerror(s, ERR_R_INTERNAL_ERROR);
2266 		goto err;
2267 	}
2268 	if (!EVP_PKEY_get_default_digest_nid(pkey, &nid) ||
2269 	    (md = EVP_get_digestbynid(nid)) == NULL) {
2270 		SSLerror(s, ERR_R_EVP_LIB);
2271 		goto err;
2272 	}
2273 	if (!EVP_DigestSignInit(mctx, &pctx, md, NULL, pkey)) {
2274 		SSLerror(s, ERR_R_EVP_LIB);
2275 		goto err;
2276 	}
2277 	if (EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_SIGN,
2278 	    EVP_PKEY_CTRL_GOST_SIG_FORMAT, GOST_SIG_FORMAT_RS_LE, NULL) <= 0) {
2279 		SSLerror(s, ERR_R_EVP_LIB);
2280 		goto err;
2281 	}
2282 	if (!EVP_DigestSignUpdate(mctx, hdata, hdata_len)) {
2283 		SSLerror(s, ERR_R_EVP_LIB);
2284 		goto err;
2285 	}
2286 	if (!EVP_DigestSignFinal(mctx, NULL, &signature_len) ||
2287 	    signature_len == 0) {
2288 		SSLerror(s, ERR_R_EVP_LIB);
2289 		goto err;
2290 	}
2291 	if ((signature = calloc(1, signature_len)) == NULL) {
2292 		SSLerror(s, ERR_R_MALLOC_FAILURE);
2293 		goto err;
2294 	}
2295 	if (!EVP_DigestSignFinal(mctx, signature, &signature_len)) {
2296 		SSLerror(s, ERR_R_EVP_LIB);
2297 		goto err;
2298 	}
2299 
2300 	if (!CBB_add_u16_length_prefixed(cert_verify, &cbb_signature))
2301 		goto err;
2302 	if (!CBB_add_bytes(&cbb_signature, signature, signature_len))
2303 		goto err;
2304 	if (!CBB_flush(cert_verify))
2305 		goto err;
2306 
2307 	ret = 1;
2308  err:
2309 	EVP_MD_CTX_free(mctx);
2310 	free(signature);
2311 	return ret;
2312 }
2313 #endif
2314 
2315 int
2316 ssl3_send_client_verify(SSL *s)
2317 {
2318 	const struct ssl_sigalg *sigalg;
2319 	CBB cbb, cert_verify;
2320 	EVP_PKEY *pkey;
2321 
2322 	memset(&cbb, 0, sizeof(cbb));
2323 
2324 	if (s->s3->hs.state == SSL3_ST_CW_CERT_VRFY_A) {
2325 		if (!ssl3_handshake_msg_start(s, &cbb, &cert_verify,
2326 		    SSL3_MT_CERTIFICATE_VERIFY))
2327 			goto err;
2328 
2329 		pkey = s->cert->key->privatekey;
2330 		if ((sigalg = ssl_sigalg_select(s, pkey)) == NULL) {
2331 			SSLerror(s, SSL_R_SIGNATURE_ALGORITHMS_ERROR);
2332 			goto err;
2333 		}
2334 		s->s3->hs.our_sigalg = sigalg;
2335 
2336 		/*
2337 		 * For TLS v1.2 send signature algorithm and signature using
2338 		 * agreed digest and cached handshake records.
2339 		 */
2340 		if (SSL_USE_SIGALGS(s)) {
2341 			if (!ssl3_send_client_verify_sigalgs(s, pkey, sigalg,
2342 			    &cert_verify))
2343 				goto err;
2344 		} else if (EVP_PKEY_id(pkey) == EVP_PKEY_RSA) {
2345 			if (!ssl3_send_client_verify_rsa(s, pkey, &cert_verify))
2346 				goto err;
2347 		} else if (EVP_PKEY_id(pkey) == EVP_PKEY_EC) {
2348 			if (!ssl3_send_client_verify_ec(s, pkey, &cert_verify))
2349 				goto err;
2350 #ifndef OPENSSL_NO_GOST
2351 		} else if (EVP_PKEY_id(pkey) == NID_id_GostR3410_94 ||
2352 		    EVP_PKEY_id(pkey) == NID_id_GostR3410_2001) {
2353 			if (!ssl3_send_client_verify_gost(s, pkey, &cert_verify))
2354 				goto err;
2355 #endif
2356 		} else {
2357 			SSLerror(s, ERR_R_INTERNAL_ERROR);
2358 			goto err;
2359 		}
2360 
2361 		tls1_transcript_free(s);
2362 
2363 		if (!ssl3_handshake_msg_finish(s, &cbb))
2364 			goto err;
2365 
2366 		s->s3->hs.state = SSL3_ST_CW_CERT_VRFY_B;
2367 	}
2368 
2369 	return (ssl3_handshake_write(s));
2370 
2371  err:
2372 	CBB_cleanup(&cbb);
2373 
2374 	return (-1);
2375 }
2376 
2377 int
2378 ssl3_send_client_certificate(SSL *s)
2379 {
2380 	EVP_PKEY *pkey = NULL;
2381 	X509 *x509 = NULL;
2382 	CBB cbb, client_cert;
2383 	int i;
2384 
2385 	memset(&cbb, 0, sizeof(cbb));
2386 
2387 	if (s->s3->hs.state == SSL3_ST_CW_CERT_A) {
2388 		if (s->cert->key->x509 == NULL ||
2389 		    s->cert->key->privatekey == NULL)
2390 			s->s3->hs.state = SSL3_ST_CW_CERT_B;
2391 		else
2392 			s->s3->hs.state = SSL3_ST_CW_CERT_C;
2393 	}
2394 
2395 	/* We need to get a client cert */
2396 	if (s->s3->hs.state == SSL3_ST_CW_CERT_B) {
2397 		/*
2398 		 * If we get an error, we need to
2399 		 * ssl->internal->rwstate = SSL_X509_LOOKUP; return(-1);
2400 		 * We then get retried later.
2401 		 */
2402 		i = ssl_do_client_cert_cb(s, &x509, &pkey);
2403 		if (i < 0) {
2404 			s->internal->rwstate = SSL_X509_LOOKUP;
2405 			return (-1);
2406 		}
2407 		s->internal->rwstate = SSL_NOTHING;
2408 		if ((i == 1) && (pkey != NULL) && (x509 != NULL)) {
2409 			s->s3->hs.state = SSL3_ST_CW_CERT_B;
2410 			if (!SSL_use_certificate(s, x509) ||
2411 			    !SSL_use_PrivateKey(s, pkey))
2412 				i = 0;
2413 		} else if (i == 1) {
2414 			i = 0;
2415 			SSLerror(s, SSL_R_BAD_DATA_RETURNED_BY_CALLBACK);
2416 		}
2417 
2418 		X509_free(x509);
2419 		EVP_PKEY_free(pkey);
2420 		if (i == 0) {
2421 			s->s3->hs.tls12.cert_request = 2;
2422 
2423 			/* There is no client certificate to verify. */
2424 			tls1_transcript_free(s);
2425 		}
2426 
2427 		/* Ok, we have a cert */
2428 		s->s3->hs.state = SSL3_ST_CW_CERT_C;
2429 	}
2430 
2431 	if (s->s3->hs.state == SSL3_ST_CW_CERT_C) {
2432 		if (!ssl3_handshake_msg_start(s, &cbb, &client_cert,
2433 		    SSL3_MT_CERTIFICATE))
2434 			goto err;
2435 		if (!ssl3_output_cert_chain(s, &client_cert,
2436 		    (s->s3->hs.tls12.cert_request == 2) ? NULL : s->cert->key))
2437 			goto err;
2438 		if (!ssl3_handshake_msg_finish(s, &cbb))
2439 			goto err;
2440 
2441 		s->s3->hs.state = SSL3_ST_CW_CERT_D;
2442 	}
2443 
2444 	/* SSL3_ST_CW_CERT_D */
2445 	return (ssl3_handshake_write(s));
2446 
2447  err:
2448 	CBB_cleanup(&cbb);
2449 
2450 	return (0);
2451 }
2452 
2453 #define has_bits(i,m)	(((i)&(m)) == (m))
2454 
2455 int
2456 ssl3_check_cert_and_algorithm(SSL *s)
2457 {
2458 	long alg_k, alg_a;
2459 	int nid = NID_undef;
2460 	int i;
2461 
2462 	alg_k = s->s3->hs.cipher->algorithm_mkey;
2463 	alg_a = s->s3->hs.cipher->algorithm_auth;
2464 
2465 	/* We don't have a certificate. */
2466 	if (alg_a & SSL_aNULL)
2467 		return (1);
2468 
2469 	if (s->s3->hs.key_share != NULL)
2470 		nid = tls_key_share_nid(s->s3->hs.key_share);
2471 
2472 	/* This is the passed certificate. */
2473 
2474 	if (s->session->peer_cert_type == SSL_PKEY_ECC) {
2475 		if (!ssl_check_srvr_ecc_cert_and_alg(s, s->session->peer_cert)) {
2476 			SSLerror(s, SSL_R_BAD_ECC_CERT);
2477 			goto fatal_err;
2478 		}
2479 		return (1);
2480 	}
2481 
2482 	i = X509_certificate_type(s->session->peer_cert, NULL);
2483 
2484 	/* Check that we have a certificate if we require one. */
2485 	if ((alg_a & SSL_aRSA) && !has_bits(i, EVP_PK_RSA|EVP_PKT_SIGN)) {
2486 		SSLerror(s, SSL_R_MISSING_RSA_SIGNING_CERT);
2487 		goto fatal_err;
2488 	}
2489 	if ((alg_k & SSL_kRSA) && !has_bits(i, EVP_PK_RSA|EVP_PKT_ENC)) {
2490 		SSLerror(s, SSL_R_MISSING_RSA_ENCRYPTING_CERT);
2491 		goto fatal_err;
2492 	}
2493 	if ((alg_k & SSL_kDHE) &&
2494 	    !(has_bits(i, EVP_PK_DH|EVP_PKT_EXCH) || (nid == NID_dhKeyAgreement))) {
2495 		SSLerror(s, SSL_R_MISSING_DH_KEY);
2496 		goto fatal_err;
2497 	}
2498 
2499 	return (1);
2500 
2501  fatal_err:
2502 	ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
2503 
2504 	return (0);
2505 }
2506 
2507 /*
2508  * Check to see if handshake is full or resumed. Usually this is just a
2509  * case of checking to see if a cache hit has occurred. In the case of
2510  * session tickets we have to check the next message to be sure.
2511  */
2512 
2513 int
2514 ssl3_check_finished(SSL *s)
2515 {
2516 	int ret;
2517 
2518 	/* If we have no ticket it cannot be a resumed session. */
2519 	if (!s->session->tlsext_tick)
2520 		return (1);
2521 	/* this function is called when we really expect a Certificate
2522 	 * message, so permit appropriate message length */
2523 	if ((ret = ssl3_get_message(s, SSL3_ST_CR_CERT_A,
2524 	    SSL3_ST_CR_CERT_B, -1, s->internal->max_cert_list)) <= 0)
2525 		return ret;
2526 
2527 	s->s3->hs.tls12.reuse_message = 1;
2528 	if ((s->s3->hs.tls12.message_type == SSL3_MT_FINISHED) ||
2529 	    (s->s3->hs.tls12.message_type == SSL3_MT_NEWSESSION_TICKET))
2530 		return (2);
2531 
2532 	return (1);
2533 }
2534 
2535 int
2536 ssl_do_client_cert_cb(SSL *s, X509 **px509, EVP_PKEY **ppkey)
2537 {
2538 	int	i = 0;
2539 
2540 #ifndef OPENSSL_NO_ENGINE
2541 	if (s->ctx->internal->client_cert_engine) {
2542 		i = ENGINE_load_ssl_client_cert(
2543 		    s->ctx->internal->client_cert_engine, s,
2544 		    SSL_get_client_CA_list(s), px509, ppkey, NULL, NULL, NULL);
2545 		if (i != 0)
2546 			return (i);
2547 	}
2548 #endif
2549 	if (s->ctx->internal->client_cert_cb)
2550 		i = s->ctx->internal->client_cert_cb(s, px509, ppkey);
2551 	return (i);
2552 }
2553