xref: /openbsd-src/lib/libssl/ssl_clnt.c (revision f84b1df5a16cdd762c93854218de246e79975d3b)
1 /* $OpenBSD: ssl_clnt.c,v 1.141 2022/02/05 14:54:10 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 (!ssl3_setup_init_buffer(s)) {
225 				ret = -1;
226 				goto end;
227 			}
228 			if (!ssl3_setup_buffers(s)) {
229 				ret = -1;
230 				goto end;
231 			}
232 			if (!ssl_init_wbio_buffer(s, 0)) {
233 				ret = -1;
234 				goto end;
235 			}
236 
237 			/* don't push the buffering BIO quite yet */
238 
239 			if (!tls1_transcript_init(s)) {
240 				ret = -1;
241 				goto end;
242 			}
243 
244 			s->s3->hs.state = SSL3_ST_CW_CLNT_HELLO_A;
245 			s->ctx->internal->stats.sess_connect++;
246 			s->internal->init_num = 0;
247 
248 			if (SSL_is_dtls(s)) {
249 				/* mark client_random uninitialized */
250 				memset(s->s3->client_random, 0,
251 				    sizeof(s->s3->client_random));
252 				s->d1->send_cookie = 0;
253 				s->internal->hit = 0;
254 			}
255 			break;
256 
257 		case SSL3_ST_CW_CLNT_HELLO_A:
258 		case SSL3_ST_CW_CLNT_HELLO_B:
259 			s->internal->shutdown = 0;
260 
261 			if (SSL_is_dtls(s)) {
262 				/* every DTLS ClientHello resets Finished MAC */
263 				tls1_transcript_reset(s);
264 
265 				dtls1_start_timer(s);
266 			}
267 
268 			ret = ssl3_send_client_hello(s);
269 			if (ret <= 0)
270 				goto end;
271 
272 			if (SSL_is_dtls(s) && s->d1->send_cookie) {
273 				s->s3->hs.state = SSL3_ST_CW_FLUSH;
274 				s->s3->hs.tls12.next_state = SSL3_ST_CR_SRVR_HELLO_A;
275 			} else
276 				s->s3->hs.state = SSL3_ST_CR_SRVR_HELLO_A;
277 
278 			s->internal->init_num = 0;
279 
280 			/* turn on buffering for the next lot of output */
281 			if (s->bbio != s->wbio)
282 				s->wbio = BIO_push(s->bbio, s->wbio);
283 
284 			break;
285 
286 		case SSL3_ST_CR_SRVR_HELLO_A:
287 		case SSL3_ST_CR_SRVR_HELLO_B:
288 			ret = ssl3_get_server_hello(s);
289 			if (ret <= 0)
290 				goto end;
291 
292 			if (s->internal->hit) {
293 				s->s3->hs.state = SSL3_ST_CR_FINISHED_A;
294 				if (!SSL_is_dtls(s)) {
295 					if (s->internal->tlsext_ticket_expected) {
296 						/* receive renewed session ticket */
297 						s->s3->hs.state = SSL3_ST_CR_SESSION_TICKET_A;
298 					}
299 
300 					/* No client certificate verification. */
301 					tls1_transcript_free(s);
302 				}
303 			} else if (SSL_is_dtls(s)) {
304 				s->s3->hs.state = DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A;
305 			} else {
306 				s->s3->hs.state = SSL3_ST_CR_CERT_A;
307 			}
308 			s->internal->init_num = 0;
309 			break;
310 
311 		case DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A:
312 		case DTLS1_ST_CR_HELLO_VERIFY_REQUEST_B:
313 			ret = ssl3_get_dtls_hello_verify(s);
314 			if (ret <= 0)
315 				goto end;
316 			dtls1_stop_timer(s);
317 			if (s->d1->send_cookie) /* start again, with a cookie */
318 				s->s3->hs.state = SSL3_ST_CW_CLNT_HELLO_A;
319 			else
320 				s->s3->hs.state = SSL3_ST_CR_CERT_A;
321 			s->internal->init_num = 0;
322 			break;
323 
324 		case SSL3_ST_CR_CERT_A:
325 		case SSL3_ST_CR_CERT_B:
326 			ret = ssl3_check_finished(s);
327 			if (ret <= 0)
328 				goto end;
329 			if (ret == 2) {
330 				s->internal->hit = 1;
331 				if (s->internal->tlsext_ticket_expected)
332 					s->s3->hs.state = SSL3_ST_CR_SESSION_TICKET_A;
333 				else
334 					s->s3->hs.state = SSL3_ST_CR_FINISHED_A;
335 				s->internal->init_num = 0;
336 				break;
337 			}
338 			/* Check if it is anon DH/ECDH. */
339 			if (!(s->s3->hs.cipher->algorithm_auth &
340 			    SSL_aNULL)) {
341 				ret = ssl3_get_server_certificate(s);
342 				if (ret <= 0)
343 					goto end;
344 				if (s->internal->tlsext_status_expected)
345 					s->s3->hs.state = SSL3_ST_CR_CERT_STATUS_A;
346 				else
347 					s->s3->hs.state = SSL3_ST_CR_KEY_EXCH_A;
348 			} else {
349 				skip = 1;
350 				s->s3->hs.state = SSL3_ST_CR_KEY_EXCH_A;
351 			}
352 			s->internal->init_num = 0;
353 			break;
354 
355 		case SSL3_ST_CR_KEY_EXCH_A:
356 		case SSL3_ST_CR_KEY_EXCH_B:
357 			ret = ssl3_get_server_key_exchange(s);
358 			if (ret <= 0)
359 				goto end;
360 			s->s3->hs.state = SSL3_ST_CR_CERT_REQ_A;
361 			s->internal->init_num = 0;
362 
363 			/*
364 			 * At this point we check that we have the
365 			 * required stuff from the server.
366 			 */
367 			if (!ssl3_check_cert_and_algorithm(s)) {
368 				ret = -1;
369 				goto end;
370 			}
371 			break;
372 
373 		case SSL3_ST_CR_CERT_REQ_A:
374 		case SSL3_ST_CR_CERT_REQ_B:
375 			ret = ssl3_get_certificate_request(s);
376 			if (ret <= 0)
377 				goto end;
378 			s->s3->hs.state = SSL3_ST_CR_SRVR_DONE_A;
379 			s->internal->init_num = 0;
380 			break;
381 
382 		case SSL3_ST_CR_SRVR_DONE_A:
383 		case SSL3_ST_CR_SRVR_DONE_B:
384 			ret = ssl3_get_server_done(s);
385 			if (ret <= 0)
386 				goto end;
387 			if (SSL_is_dtls(s))
388 				dtls1_stop_timer(s);
389 			if (s->s3->hs.tls12.cert_request)
390 				s->s3->hs.state = SSL3_ST_CW_CERT_A;
391 			else
392 				s->s3->hs.state = SSL3_ST_CW_KEY_EXCH_A;
393 			s->internal->init_num = 0;
394 
395 			break;
396 
397 		case SSL3_ST_CW_CERT_A:
398 		case SSL3_ST_CW_CERT_B:
399 		case SSL3_ST_CW_CERT_C:
400 		case SSL3_ST_CW_CERT_D:
401 			if (SSL_is_dtls(s))
402 				dtls1_start_timer(s);
403 			ret = ssl3_send_client_certificate(s);
404 			if (ret <= 0)
405 				goto end;
406 			s->s3->hs.state = SSL3_ST_CW_KEY_EXCH_A;
407 			s->internal->init_num = 0;
408 			break;
409 
410 		case SSL3_ST_CW_KEY_EXCH_A:
411 		case SSL3_ST_CW_KEY_EXCH_B:
412 			if (SSL_is_dtls(s))
413 				dtls1_start_timer(s);
414 			ret = ssl3_send_client_key_exchange(s);
415 			if (ret <= 0)
416 				goto end;
417 			/*
418 			 * EAY EAY EAY need to check for DH fix cert
419 			 * sent back
420 			 */
421 			/*
422 			 * For TLS, cert_req is set to 2, so a cert chain
423 			 * of nothing is sent, but no verify packet is sent
424 			 */
425 			/*
426 			 * XXX: For now, we do not support client
427 			 * authentication in ECDH cipher suites with
428 			 * ECDH (rather than ECDSA) certificates.
429 			 * We need to skip the certificate verify
430 			 * message when client's ECDH public key is sent
431 			 * inside the client certificate.
432 			 */
433 			if (s->s3->hs.tls12.cert_request == 1) {
434 				s->s3->hs.state = SSL3_ST_CW_CERT_VRFY_A;
435 			} else {
436 				s->s3->hs.state = SSL3_ST_CW_CHANGE_A;
437 				s->s3->change_cipher_spec = 0;
438 			}
439 			if (!SSL_is_dtls(s)) {
440 				if (s->s3->flags & TLS1_FLAGS_SKIP_CERT_VERIFY) {
441 					s->s3->hs.state = SSL3_ST_CW_CHANGE_A;
442 					s->s3->change_cipher_spec = 0;
443 				}
444 			}
445 
446 			s->internal->init_num = 0;
447 			break;
448 
449 		case SSL3_ST_CW_CERT_VRFY_A:
450 		case SSL3_ST_CW_CERT_VRFY_B:
451 			if (SSL_is_dtls(s))
452 				dtls1_start_timer(s);
453 			ret = ssl3_send_client_verify(s);
454 			if (ret <= 0)
455 				goto end;
456 			s->s3->hs.state = SSL3_ST_CW_CHANGE_A;
457 			s->internal->init_num = 0;
458 			s->s3->change_cipher_spec = 0;
459 			break;
460 
461 		case SSL3_ST_CW_CHANGE_A:
462 		case SSL3_ST_CW_CHANGE_B:
463 			if (SSL_is_dtls(s) && !s->internal->hit)
464 				dtls1_start_timer(s);
465 			ret = ssl3_send_change_cipher_spec(s,
466 			    SSL3_ST_CW_CHANGE_A, SSL3_ST_CW_CHANGE_B);
467 			if (ret <= 0)
468 				goto end;
469 
470 			s->s3->hs.state = SSL3_ST_CW_FINISHED_A;
471 			s->internal->init_num = 0;
472 			s->session->cipher = s->s3->hs.cipher;
473 
474 			if (!tls1_setup_key_block(s)) {
475 				ret = -1;
476 				goto end;
477 			}
478 			if (!tls1_change_write_cipher_state(s)) {
479 				ret = -1;
480 				goto end;
481 			}
482 			break;
483 
484 		case SSL3_ST_CW_FINISHED_A:
485 		case SSL3_ST_CW_FINISHED_B:
486 			if (SSL_is_dtls(s) && !s->internal->hit)
487 				dtls1_start_timer(s);
488 			ret = ssl3_send_finished(s, SSL3_ST_CW_FINISHED_A,
489 			    SSL3_ST_CW_FINISHED_B);
490 			if (ret <= 0)
491 				goto end;
492 			if (!SSL_is_dtls(s))
493 				s->s3->flags |= SSL3_FLAGS_CCS_OK;
494 			s->s3->hs.state = SSL3_ST_CW_FLUSH;
495 
496 			/* clear flags */
497 			if (s->internal->hit) {
498 				s->s3->hs.tls12.next_state = SSL_ST_OK;
499 			} else {
500 				/* Allow NewSessionTicket if ticket expected */
501 				if (s->internal->tlsext_ticket_expected)
502 					s->s3->hs.tls12.next_state =
503 					    SSL3_ST_CR_SESSION_TICKET_A;
504 				else
505 					s->s3->hs.tls12.next_state =
506 					    SSL3_ST_CR_FINISHED_A;
507 			}
508 			s->internal->init_num = 0;
509 			break;
510 
511 		case SSL3_ST_CR_SESSION_TICKET_A:
512 		case SSL3_ST_CR_SESSION_TICKET_B:
513 			ret = ssl3_get_new_session_ticket(s);
514 			if (ret <= 0)
515 				goto end;
516 			s->s3->hs.state = SSL3_ST_CR_FINISHED_A;
517 			s->internal->init_num = 0;
518 			break;
519 
520 		case SSL3_ST_CR_CERT_STATUS_A:
521 		case SSL3_ST_CR_CERT_STATUS_B:
522 			ret = ssl3_get_cert_status(s);
523 			if (ret <= 0)
524 				goto end;
525 			s->s3->hs.state = SSL3_ST_CR_KEY_EXCH_A;
526 			s->internal->init_num = 0;
527 			break;
528 
529 		case SSL3_ST_CR_FINISHED_A:
530 		case SSL3_ST_CR_FINISHED_B:
531 			if (SSL_is_dtls(s))
532 				s->d1->change_cipher_spec_ok = 1;
533 			else
534 				s->s3->flags |= SSL3_FLAGS_CCS_OK;
535 			ret = ssl3_get_finished(s, SSL3_ST_CR_FINISHED_A,
536 			    SSL3_ST_CR_FINISHED_B);
537 			if (ret <= 0)
538 				goto end;
539 			if (SSL_is_dtls(s))
540 				dtls1_stop_timer(s);
541 
542 			if (s->internal->hit)
543 				s->s3->hs.state = SSL3_ST_CW_CHANGE_A;
544 			else
545 				s->s3->hs.state = SSL_ST_OK;
546 			s->internal->init_num = 0;
547 			break;
548 
549 		case SSL3_ST_CW_FLUSH:
550 			s->internal->rwstate = SSL_WRITING;
551 			if (BIO_flush(s->wbio) <= 0) {
552 				if (SSL_is_dtls(s)) {
553 					/* If the write error was fatal, stop trying */
554 					if (!BIO_should_retry(s->wbio)) {
555 						s->internal->rwstate = SSL_NOTHING;
556 						s->s3->hs.state = s->s3->hs.tls12.next_state;
557 					}
558 				}
559 				ret = -1;
560 				goto end;
561 			}
562 			s->internal->rwstate = SSL_NOTHING;
563 			s->s3->hs.state = s->s3->hs.tls12.next_state;
564 			break;
565 
566 		case SSL_ST_OK:
567 			/* clean a few things up */
568 			tls1_cleanup_key_block(s);
569 
570 			if (s->s3->handshake_transcript != NULL) {
571 				SSLerror(s, ERR_R_INTERNAL_ERROR);
572 				ret = -1;
573 				goto end;
574 			}
575 
576 			if (!SSL_is_dtls(s))
577 				ssl3_release_init_buffer(s);
578 
579 			ssl_free_wbio_buffer(s);
580 
581 			s->internal->init_num = 0;
582 			s->internal->renegotiate = 0;
583 			s->internal->new_session = 0;
584 
585 			ssl_update_cache(s, SSL_SESS_CACHE_CLIENT);
586 			if (s->internal->hit)
587 				s->ctx->internal->stats.sess_hit++;
588 
589 			ret = 1;
590 			/* s->server=0; */
591 			s->internal->handshake_func = ssl3_connect;
592 			s->ctx->internal->stats.sess_connect_good++;
593 
594 			ssl_info_callback(s, SSL_CB_HANDSHAKE_DONE, 1);
595 
596 			if (SSL_is_dtls(s)) {
597 				/* done with handshaking */
598 				s->d1->handshake_read_seq = 0;
599 				s->d1->next_handshake_write_seq = 0;
600 			}
601 
602 			goto end;
603 			/* break; */
604 
605 		default:
606 			SSLerror(s, SSL_R_UNKNOWN_STATE);
607 			ret = -1;
608 			goto end;
609 			/* break; */
610 		}
611 
612 		/* did we do anything */
613 		if (!s->s3->hs.tls12.reuse_message && !skip) {
614 			if (s->internal->debug) {
615 				if ((ret = BIO_flush(s->wbio)) <= 0)
616 					goto end;
617 			}
618 
619 			if (s->s3->hs.state != state) {
620 				new_state = s->s3->hs.state;
621 				s->s3->hs.state = state;
622 				ssl_info_callback(s, SSL_CB_CONNECT_LOOP, 1);
623 				s->s3->hs.state = new_state;
624 			}
625 		}
626 		skip = 0;
627 	}
628 
629  end:
630 	s->internal->in_handshake--;
631 	ssl_info_callback(s, SSL_CB_CONNECT_EXIT, ret);
632 
633 	return (ret);
634 }
635 
636 int
637 ssl3_send_client_hello(SSL *s)
638 {
639 	CBB cbb, client_hello, session_id, cookie, cipher_suites;
640 	CBB compression_methods;
641 	uint16_t max_version;
642 	size_t sl;
643 
644 	memset(&cbb, 0, sizeof(cbb));
645 
646 	if (s->s3->hs.state == SSL3_ST_CW_CLNT_HELLO_A) {
647 		SSL_SESSION *sess = s->session;
648 
649 		if (!ssl_max_supported_version(s, &max_version)) {
650 			SSLerror(s, SSL_R_NO_PROTOCOLS_AVAILABLE);
651 			return (-1);
652 		}
653 		s->version = max_version;
654 
655 		if (sess == NULL ||
656 		    sess->ssl_version != s->version ||
657 		    (!sess->session_id_length && !sess->tlsext_tick) ||
658 		    sess->not_resumable) {
659 			if (!ssl_get_new_session(s, 0))
660 				goto err;
661 		}
662 		/* else use the pre-loaded session */
663 
664 		/*
665 		 * If a DTLS ClientHello message is being resent after a
666 		 * HelloVerifyRequest, we must retain the original client
667 		 * random value.
668 		 */
669 		if (!SSL_is_dtls(s) || s->d1->send_cookie == 0)
670 			arc4random_buf(s->s3->client_random, SSL3_RANDOM_SIZE);
671 
672 		if (!ssl3_handshake_msg_start(s, &cbb, &client_hello,
673 		    SSL3_MT_CLIENT_HELLO))
674 			goto err;
675 
676 		if (!CBB_add_u16(&client_hello, s->version))
677 			goto err;
678 
679 		/* Random stuff */
680 		if (!CBB_add_bytes(&client_hello, s->s3->client_random,
681 		    sizeof(s->s3->client_random)))
682 			goto err;
683 
684 		/* Session ID */
685 		if (!CBB_add_u8_length_prefixed(&client_hello, &session_id))
686 			goto err;
687 		if (!s->internal->new_session &&
688 		    s->session->session_id_length > 0) {
689 			sl = s->session->session_id_length;
690 			if (sl > sizeof(s->session->session_id)) {
691 				SSLerror(s, ERR_R_INTERNAL_ERROR);
692 				goto err;
693 			}
694 			if (!CBB_add_bytes(&session_id,
695 			    s->session->session_id, sl))
696 				goto err;
697 		}
698 
699 		/* DTLS Cookie. */
700 		if (SSL_is_dtls(s)) {
701 			if (s->d1->cookie_len > sizeof(s->d1->cookie)) {
702 				SSLerror(s, ERR_R_INTERNAL_ERROR);
703 				goto err;
704 			}
705 			if (!CBB_add_u8_length_prefixed(&client_hello, &cookie))
706 				goto err;
707 			if (!CBB_add_bytes(&cookie, s->d1->cookie,
708 			    s->d1->cookie_len))
709 				goto err;
710 		}
711 
712 		/* Ciphers supported */
713 		if (!CBB_add_u16_length_prefixed(&client_hello, &cipher_suites))
714 			return 0;
715 		if (!ssl_cipher_list_to_bytes(s, SSL_get_ciphers(s),
716 		    &cipher_suites)) {
717 			SSLerror(s, SSL_R_NO_CIPHERS_AVAILABLE);
718 			goto err;
719 		}
720 
721 		/* Add in compression methods (null) */
722 		if (!CBB_add_u8_length_prefixed(&client_hello,
723 		    &compression_methods))
724 			goto err;
725 		if (!CBB_add_u8(&compression_methods, 0))
726 			goto err;
727 
728 		/* TLS extensions */
729 		if (!tlsext_client_build(s, SSL_TLSEXT_MSG_CH, &client_hello)) {
730 			SSLerror(s, ERR_R_INTERNAL_ERROR);
731 			goto err;
732 		}
733 
734 		if (!ssl3_handshake_msg_finish(s, &cbb))
735 			goto err;
736 
737 		s->s3->hs.state = SSL3_ST_CW_CLNT_HELLO_B;
738 	}
739 
740 	/* SSL3_ST_CW_CLNT_HELLO_B */
741 	return (ssl3_handshake_write(s));
742 
743  err:
744 	CBB_cleanup(&cbb);
745 
746 	return (-1);
747 }
748 
749 int
750 ssl3_get_dtls_hello_verify(SSL *s)
751 {
752 	CBS hello_verify_request, cookie;
753 	size_t cookie_len;
754 	uint16_t ssl_version;
755 	int al, ret;
756 
757 	if ((ret = ssl3_get_message(s, DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A,
758 	    DTLS1_ST_CR_HELLO_VERIFY_REQUEST_B, -1, s->internal->max_cert_list)) <= 0)
759 		return ret;
760 
761 	if (s->s3->hs.tls12.message_type != DTLS1_MT_HELLO_VERIFY_REQUEST) {
762 		s->d1->send_cookie = 0;
763 		s->s3->hs.tls12.reuse_message = 1;
764 		return (1);
765 	}
766 
767 	if (s->internal->init_num < 0)
768 		goto decode_err;
769 
770 	CBS_init(&hello_verify_request, s->internal->init_msg,
771 	    s->internal->init_num);
772 
773 	if (!CBS_get_u16(&hello_verify_request, &ssl_version))
774 		goto decode_err;
775 	if (!CBS_get_u8_length_prefixed(&hello_verify_request, &cookie))
776 		goto decode_err;
777 	if (CBS_len(&hello_verify_request) != 0)
778 		goto decode_err;
779 
780 	/*
781 	 * Per RFC 6347 section 4.2.1, the HelloVerifyRequest should always
782 	 * contain DTLSv1.0 the version that is going to be negotiated.
783 	 * Tolerate DTLSv1.2 just in case.
784 	 */
785 	if (ssl_version != DTLS1_VERSION && ssl_version != DTLS1_2_VERSION) {
786 		SSLerror(s, SSL_R_WRONG_SSL_VERSION);
787 		s->version = (s->version & 0xff00) | (ssl_version & 0xff);
788 		al = SSL_AD_PROTOCOL_VERSION;
789 		goto fatal_err;
790 	}
791 
792 	if (!CBS_write_bytes(&cookie, s->d1->cookie,
793 	    sizeof(s->d1->cookie), &cookie_len)) {
794 		s->d1->cookie_len = 0;
795 		al = SSL_AD_ILLEGAL_PARAMETER;
796 		goto fatal_err;
797 	}
798 	s->d1->cookie_len = cookie_len;
799 	s->d1->send_cookie = 1;
800 
801 	return 1;
802 
803  decode_err:
804 	al = SSL_AD_DECODE_ERROR;
805  fatal_err:
806 	ssl3_send_alert(s, SSL3_AL_FATAL, al);
807 	return -1;
808 }
809 
810 int
811 ssl3_get_server_hello(SSL *s)
812 {
813 	CBS cbs, server_random, session_id;
814 	uint16_t server_version, cipher_suite;
815 	uint8_t compression_method;
816 	const SSL_CIPHER *cipher;
817 	const SSL_METHOD *method;
818 	unsigned long alg_k;
819 	size_t outlen;
820 	int al, ret;
821 
822 	s->internal->first_packet = 1;
823 	if ((ret = ssl3_get_message(s, SSL3_ST_CR_SRVR_HELLO_A,
824 	    SSL3_ST_CR_SRVR_HELLO_B, -1, 20000 /* ?? */)) <= 0)
825 		return ret;
826 	s->internal->first_packet = 0;
827 
828 	if (s->internal->init_num < 0)
829 		goto decode_err;
830 
831 	CBS_init(&cbs, s->internal->init_msg, s->internal->init_num);
832 
833 	if (SSL_is_dtls(s)) {
834 		if (s->s3->hs.tls12.message_type == DTLS1_MT_HELLO_VERIFY_REQUEST) {
835 			if (s->d1->send_cookie == 0) {
836 				s->s3->hs.tls12.reuse_message = 1;
837 				return (1);
838 			} else {
839 				/* Already sent a cookie. */
840 				al = SSL_AD_UNEXPECTED_MESSAGE;
841 				SSLerror(s, SSL_R_BAD_MESSAGE_TYPE);
842 				goto fatal_err;
843 			}
844 		}
845 	}
846 
847 	if (s->s3->hs.tls12.message_type != SSL3_MT_SERVER_HELLO) {
848 		al = SSL_AD_UNEXPECTED_MESSAGE;
849 		SSLerror(s, SSL_R_BAD_MESSAGE_TYPE);
850 		goto fatal_err;
851 	}
852 
853 	if (!CBS_get_u16(&cbs, &server_version))
854 		goto decode_err;
855 
856 	if (!ssl_check_version_from_server(s, server_version)) {
857 		SSLerror(s, SSL_R_WRONG_SSL_VERSION);
858 		s->version = (s->version & 0xff00) | (server_version & 0xff);
859 		al = SSL_AD_PROTOCOL_VERSION;
860 		goto fatal_err;
861 	}
862 	s->s3->hs.peer_legacy_version = server_version;
863 	s->version = server_version;
864 
865 	s->s3->hs.negotiated_tls_version = ssl_tls_version(server_version);
866 	if (s->s3->hs.negotiated_tls_version == 0) {
867 		SSLerror(s, ERR_R_INTERNAL_ERROR);
868 		goto err;
869 	}
870 
871 	if ((method = ssl_get_method(server_version)) == NULL) {
872 		SSLerror(s, ERR_R_INTERNAL_ERROR);
873 		goto err;
874 	}
875 	s->method = method;
876 
877 	/* Server random. */
878 	if (!CBS_get_bytes(&cbs, &server_random, SSL3_RANDOM_SIZE))
879 		goto decode_err;
880 	if (!CBS_write_bytes(&server_random, s->s3->server_random,
881 	    sizeof(s->s3->server_random), NULL))
882 		goto err;
883 
884 	if (s->s3->hs.our_max_tls_version >= TLS1_2_VERSION &&
885 	    s->s3->hs.negotiated_tls_version < s->s3->hs.our_max_tls_version) {
886 		/*
887 		 * RFC 8446 section 4.1.3. We must not downgrade if the server
888 		 * random value contains the TLS 1.2 or TLS 1.1 magical value.
889 		 */
890 		if (!CBS_skip(&server_random,
891 		    CBS_len(&server_random) - sizeof(tls13_downgrade_12)))
892 			goto err;
893 		if (s->s3->hs.negotiated_tls_version == TLS1_2_VERSION &&
894 		    CBS_mem_equal(&server_random, tls13_downgrade_12,
895 		    sizeof(tls13_downgrade_12))) {
896 			al = SSL_AD_ILLEGAL_PARAMETER;
897 			SSLerror(s, SSL_R_INAPPROPRIATE_FALLBACK);
898 			goto fatal_err;
899 		}
900 		if (CBS_mem_equal(&server_random, tls13_downgrade_11,
901 		    sizeof(tls13_downgrade_11))) {
902 			al = SSL_AD_ILLEGAL_PARAMETER;
903 			SSLerror(s, SSL_R_INAPPROPRIATE_FALLBACK);
904 			goto fatal_err;
905 		}
906 	}
907 
908 	/* Session ID. */
909 	if (!CBS_get_u8_length_prefixed(&cbs, &session_id))
910 		goto decode_err;
911 
912 	if (CBS_len(&session_id) > SSL3_SESSION_ID_SIZE) {
913 		al = SSL_AD_ILLEGAL_PARAMETER;
914 		SSLerror(s, SSL_R_SSL3_SESSION_ID_TOO_LONG);
915 		goto fatal_err;
916 	}
917 
918 	/* Cipher suite. */
919 	if (!CBS_get_u16(&cbs, &cipher_suite))
920 		goto decode_err;
921 
922 	/*
923 	 * Check if we want to resume the session based on external
924 	 * pre-shared secret.
925 	 */
926 	if (s->internal->tls_session_secret_cb) {
927 		SSL_CIPHER *pref_cipher = NULL;
928 		s->session->master_key_length = sizeof(s->session->master_key);
929 		if (s->internal->tls_session_secret_cb(s, s->session->master_key,
930 		    &s->session->master_key_length, NULL, &pref_cipher,
931 		    s->internal->tls_session_secret_cb_arg)) {
932 			s->session->cipher = pref_cipher ? pref_cipher :
933 			    ssl3_get_cipher_by_value(cipher_suite);
934 			s->s3->flags |= SSL3_FLAGS_CCS_OK;
935 		}
936 	}
937 
938 	if (s->session->session_id_length != 0 &&
939 	    CBS_mem_equal(&session_id, s->session->session_id,
940 		s->session->session_id_length)) {
941 		if (s->sid_ctx_length != s->session->sid_ctx_length ||
942 		    timingsafe_memcmp(s->session->sid_ctx,
943 		    s->sid_ctx, s->sid_ctx_length) != 0) {
944 			/* actually a client application bug */
945 			al = SSL_AD_ILLEGAL_PARAMETER;
946 			SSLerror(s, SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT);
947 			goto fatal_err;
948 		}
949 		s->s3->flags |= SSL3_FLAGS_CCS_OK;
950 		s->internal->hit = 1;
951 	} else {
952 		/* a miss or crap from the other end */
953 
954 		/* If we were trying for session-id reuse, make a new
955 		 * SSL_SESSION so we don't stuff up other people */
956 		s->internal->hit = 0;
957 		if (s->session->session_id_length > 0) {
958 			if (!ssl_get_new_session(s, 0)) {
959 				al = SSL_AD_INTERNAL_ERROR;
960 				goto fatal_err;
961 			}
962 		}
963 
964 		/*
965 		 * XXX - improve the handling for the case where there is a
966 		 * zero length session identifier.
967 		 */
968 		if (!CBS_write_bytes(&session_id, s->session->session_id,
969 		    sizeof(s->session->session_id), &outlen))
970 			goto err;
971 		s->session->session_id_length = outlen;
972 
973 		s->session->ssl_version = s->version;
974 	}
975 
976 	if ((cipher = ssl3_get_cipher_by_value(cipher_suite)) == NULL) {
977 		al = SSL_AD_ILLEGAL_PARAMETER;
978 		SSLerror(s, SSL_R_UNKNOWN_CIPHER_RETURNED);
979 		goto fatal_err;
980 	}
981 
982 	/* TLS v1.2 only ciphersuites require v1.2 or later. */
983 	if ((cipher->algorithm_ssl & SSL_TLSV1_2) &&
984 	    s->s3->hs.negotiated_tls_version < TLS1_2_VERSION) {
985 		al = SSL_AD_ILLEGAL_PARAMETER;
986 		SSLerror(s, SSL_R_WRONG_CIPHER_RETURNED);
987 		goto fatal_err;
988 	}
989 
990 	if (!ssl_cipher_in_list(SSL_get_ciphers(s), cipher)) {
991 		/* we did not say we would use this cipher */
992 		al = SSL_AD_ILLEGAL_PARAMETER;
993 		SSLerror(s, SSL_R_WRONG_CIPHER_RETURNED);
994 		goto fatal_err;
995 	}
996 
997 	/*
998 	 * Depending on the session caching (internal/external), the cipher
999 	 * and/or cipher_id values may not be set. Make sure that
1000 	 * cipher_id is set and use it for comparison.
1001 	 */
1002 	if (s->session->cipher)
1003 		s->session->cipher_id = s->session->cipher->id;
1004 	if (s->internal->hit && (s->session->cipher_id != cipher->id)) {
1005 		al = SSL_AD_ILLEGAL_PARAMETER;
1006 		SSLerror(s, SSL_R_OLD_SESSION_CIPHER_NOT_RETURNED);
1007 		goto fatal_err;
1008 	}
1009 	s->s3->hs.cipher = cipher;
1010 
1011 	if (!tls1_transcript_hash_init(s))
1012 		goto err;
1013 
1014 	/*
1015 	 * Don't digest cached records if no sigalgs: we may need them for
1016 	 * client authentication.
1017 	 */
1018 	alg_k = s->s3->hs.cipher->algorithm_mkey;
1019 	if (!(SSL_USE_SIGALGS(s) || (alg_k & SSL_kGOST)))
1020 		tls1_transcript_free(s);
1021 
1022 	if (!CBS_get_u8(&cbs, &compression_method))
1023 		goto decode_err;
1024 
1025 	if (compression_method != 0) {
1026 		al = SSL_AD_ILLEGAL_PARAMETER;
1027 		SSLerror(s, SSL_R_UNSUPPORTED_COMPRESSION_ALGORITHM);
1028 		goto fatal_err;
1029 	}
1030 
1031 	if (!tlsext_client_parse(s, SSL_TLSEXT_MSG_SH, &cbs, &al)) {
1032 		SSLerror(s, SSL_R_PARSE_TLSEXT);
1033 		goto fatal_err;
1034 	}
1035 
1036 	if (CBS_len(&cbs) != 0)
1037 		goto decode_err;
1038 
1039 	/*
1040 	 * Determine if we need to see RI. Strictly speaking if we want to
1041 	 * avoid an attack we should *always* see RI even on initial server
1042 	 * hello because the client doesn't see any renegotiation during an
1043 	 * attack. However this would mean we could not connect to any server
1044 	 * which doesn't support RI so for the immediate future tolerate RI
1045 	 * absence on initial connect only.
1046 	 */
1047 	if (!s->s3->renegotiate_seen &&
1048 	    !(s->internal->options & SSL_OP_LEGACY_SERVER_CONNECT)) {
1049 		al = SSL_AD_HANDSHAKE_FAILURE;
1050 		SSLerror(s, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
1051 		goto fatal_err;
1052 	}
1053 
1054 	if (ssl_check_serverhello_tlsext(s) <= 0) {
1055 		SSLerror(s, SSL_R_SERVERHELLO_TLSEXT);
1056 		goto err;
1057 	}
1058 
1059 	return (1);
1060 
1061  decode_err:
1062 	/* wrong packet length */
1063 	al = SSL_AD_DECODE_ERROR;
1064 	SSLerror(s, SSL_R_BAD_PACKET_LENGTH);
1065  fatal_err:
1066 	ssl3_send_alert(s, SSL3_AL_FATAL, al);
1067  err:
1068 	return (-1);
1069 }
1070 
1071 int
1072 ssl3_get_server_certificate(SSL *s)
1073 {
1074 	CBS cbs, cert_list;
1075 	X509 *x = NULL;
1076 	const unsigned char *q;
1077 	STACK_OF(X509) *sk = NULL;
1078 	EVP_PKEY *pkey;
1079 	int cert_type;
1080 	int al, ret;
1081 
1082 	if ((ret = ssl3_get_message(s, SSL3_ST_CR_CERT_A,
1083 	    SSL3_ST_CR_CERT_B, -1, s->internal->max_cert_list)) <= 0)
1084 		return ret;
1085 
1086 	ret = -1;
1087 
1088 	if (s->s3->hs.tls12.message_type == SSL3_MT_SERVER_KEY_EXCHANGE) {
1089 		s->s3->hs.tls12.reuse_message = 1;
1090 		return (1);
1091 	}
1092 
1093 	if (s->s3->hs.tls12.message_type != SSL3_MT_CERTIFICATE) {
1094 		al = SSL_AD_UNEXPECTED_MESSAGE;
1095 		SSLerror(s, SSL_R_BAD_MESSAGE_TYPE);
1096 		goto fatal_err;
1097 	}
1098 
1099 	if ((sk = sk_X509_new_null()) == NULL) {
1100 		SSLerror(s, ERR_R_MALLOC_FAILURE);
1101 		goto err;
1102 	}
1103 
1104 	if (s->internal->init_num < 0)
1105 		goto decode_err;
1106 
1107 	CBS_init(&cbs, s->internal->init_msg, s->internal->init_num);
1108 	if (CBS_len(&cbs) < 3)
1109 		goto decode_err;
1110 
1111 	if (!CBS_get_u24_length_prefixed(&cbs, &cert_list) ||
1112 	    CBS_len(&cbs) != 0) {
1113 		al = SSL_AD_DECODE_ERROR;
1114 		SSLerror(s, SSL_R_LENGTH_MISMATCH);
1115 		goto fatal_err;
1116 	}
1117 
1118 	while (CBS_len(&cert_list) > 0) {
1119 		CBS cert;
1120 
1121 		if (CBS_len(&cert_list) < 3)
1122 			goto decode_err;
1123 		if (!CBS_get_u24_length_prefixed(&cert_list, &cert)) {
1124 			al = SSL_AD_DECODE_ERROR;
1125 			SSLerror(s, SSL_R_CERT_LENGTH_MISMATCH);
1126 			goto fatal_err;
1127 		}
1128 
1129 		q = CBS_data(&cert);
1130 		x = d2i_X509(NULL, &q, CBS_len(&cert));
1131 		if (x == NULL) {
1132 			al = SSL_AD_BAD_CERTIFICATE;
1133 			SSLerror(s, ERR_R_ASN1_LIB);
1134 			goto fatal_err;
1135 		}
1136 		if (q != CBS_data(&cert) + CBS_len(&cert)) {
1137 			al = SSL_AD_DECODE_ERROR;
1138 			SSLerror(s, SSL_R_CERT_LENGTH_MISMATCH);
1139 			goto fatal_err;
1140 		}
1141 		if (!sk_X509_push(sk, x)) {
1142 			SSLerror(s, ERR_R_MALLOC_FAILURE);
1143 			goto err;
1144 		}
1145 		x = NULL;
1146 	}
1147 
1148 	if (ssl_verify_cert_chain(s, sk) <= 0 &&
1149 	    s->verify_mode != SSL_VERIFY_NONE) {
1150 		al = ssl_verify_alarm_type(s->verify_result);
1151 		SSLerror(s, SSL_R_CERTIFICATE_VERIFY_FAILED);
1152 		goto fatal_err;
1153 	}
1154 	ERR_clear_error(); /* but we keep s->verify_result */
1155 
1156 	/*
1157 	 * Inconsistency alert: cert_chain does include the peer's
1158 	 * certificate, which we don't include in s3_srvr.c
1159 	 */
1160 	x = sk_X509_value(sk, 0);
1161 
1162 	if ((pkey = X509_get0_pubkey(x)) == NULL ||
1163 	    EVP_PKEY_missing_parameters(pkey)) {
1164 		x = NULL;
1165 		al = SSL3_AL_FATAL;
1166 		SSLerror(s, SSL_R_UNABLE_TO_FIND_PUBLIC_KEY_PARAMETERS);
1167 		goto fatal_err;
1168 	}
1169 	if ((cert_type = ssl_cert_type(pkey)) < 0) {
1170 		x = NULL;
1171 		al = SSL3_AL_FATAL;
1172 		SSLerror(s, SSL_R_UNKNOWN_CERTIFICATE_TYPE);
1173 		goto fatal_err;
1174 	}
1175 
1176 	X509_up_ref(x);
1177 	X509_free(s->session->peer_cert);
1178 	s->session->peer_cert = x;
1179 	s->session->peer_cert_type = cert_type;
1180 
1181 	s->session->verify_result = s->verify_result;
1182 
1183 	sk_X509_pop_free(s->session->cert_chain, X509_free);
1184 	s->session->cert_chain = sk;
1185 	sk = NULL;
1186 
1187 	x = NULL;
1188 	ret = 1;
1189 
1190 	if (0) {
1191  decode_err:
1192 		/* wrong packet length */
1193 		al = SSL_AD_DECODE_ERROR;
1194 		SSLerror(s, SSL_R_BAD_PACKET_LENGTH);
1195  fatal_err:
1196 		ssl3_send_alert(s, SSL3_AL_FATAL, al);
1197 	}
1198  err:
1199 	X509_free(x);
1200 	sk_X509_pop_free(sk, X509_free);
1201 
1202 	return (ret);
1203 }
1204 
1205 static int
1206 ssl3_get_server_kex_dhe(SSL *s, CBS *cbs)
1207 {
1208 	int decode_error, invalid_params, invalid_key;
1209 	int nid = NID_dhKeyAgreement;
1210 
1211 	tls_key_share_free(s->s3->hs.key_share);
1212 	if ((s->s3->hs.key_share = tls_key_share_new_nid(nid)) == NULL)
1213 		goto err;
1214 
1215 	if (!tls_key_share_peer_params(s->s3->hs.key_share, cbs,
1216 	    &decode_error, &invalid_params)) {
1217 		if (decode_error) {
1218 			SSLerror(s, SSL_R_BAD_PACKET_LENGTH);
1219 			ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1220 		}
1221 		goto err;
1222 	}
1223 	if (!tls_key_share_peer_public(s->s3->hs.key_share, cbs,
1224 	    &decode_error, &invalid_key)) {
1225 		if (decode_error) {
1226 			SSLerror(s, SSL_R_BAD_PACKET_LENGTH);
1227 			ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1228 		}
1229 		goto err;
1230 	}
1231 
1232 	if (invalid_params) {
1233 		SSLerror(s, SSL_R_BAD_DH_P_LENGTH);
1234 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
1235 		goto err;
1236 	}
1237 	if (invalid_key) {
1238 		SSLerror(s, SSL_R_BAD_DH_PUB_KEY_LENGTH);
1239 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
1240 		goto err;
1241 	}
1242 
1243 	return 1;
1244 
1245  err:
1246 	return 0;
1247 }
1248 
1249 static int
1250 ssl3_get_server_kex_ecdhe(SSL *s, CBS *cbs)
1251 {
1252 	uint8_t curve_type;
1253 	uint16_t curve_id;
1254 	int decode_error;
1255 	CBS public;
1256 
1257 	if (!CBS_get_u8(cbs, &curve_type))
1258 		goto decode_err;
1259 	if (!CBS_get_u16(cbs, &curve_id))
1260 		goto decode_err;
1261 
1262 	/* Only named curves are supported. */
1263 	if (curve_type != NAMED_CURVE_TYPE) {
1264 		SSLerror(s, SSL_R_UNSUPPORTED_ELLIPTIC_CURVE);
1265 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
1266 		goto err;
1267 	}
1268 
1269 	if (!CBS_get_u8_length_prefixed(cbs, &public))
1270 		goto decode_err;
1271 
1272 	/*
1273 	 * Check that the curve is one of our preferences - if it is not,
1274 	 * the server has sent us an invalid curve.
1275 	 */
1276 	if (!tls1_check_curve(s, curve_id)) {
1277 		SSLerror(s, SSL_R_WRONG_CURVE);
1278 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
1279 		goto err;
1280 	}
1281 
1282 	tls_key_share_free(s->s3->hs.key_share);
1283 	if ((s->s3->hs.key_share = tls_key_share_new(curve_id)) == NULL)
1284 		goto err;
1285 
1286 	if (!tls_key_share_peer_public(s->s3->hs.key_share, &public,
1287 	    &decode_error, NULL)) {
1288 		if (decode_error)
1289 			goto decode_err;
1290 		goto err;
1291 	}
1292 
1293 	return 1;
1294 
1295  decode_err:
1296 	SSLerror(s, SSL_R_BAD_PACKET_LENGTH);
1297 	ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1298  err:
1299 	return 0;
1300 }
1301 
1302 int
1303 ssl3_get_server_key_exchange(SSL *s)
1304 {
1305 	CBS cbs, signature;
1306 	EVP_MD_CTX *md_ctx;
1307 	const unsigned char *param;
1308 	size_t param_len;
1309 	long alg_k, alg_a;
1310 	int al, ret;
1311 
1312 	alg_k = s->s3->hs.cipher->algorithm_mkey;
1313 	alg_a = s->s3->hs.cipher->algorithm_auth;
1314 
1315 	/*
1316 	 * Use same message size as in ssl3_get_certificate_request()
1317 	 * as ServerKeyExchange message may be skipped.
1318 	 */
1319 	if ((ret = ssl3_get_message(s, SSL3_ST_CR_KEY_EXCH_A,
1320 	    SSL3_ST_CR_KEY_EXCH_B, -1, s->internal->max_cert_list)) <= 0)
1321 		return ret;
1322 
1323 	if ((md_ctx = EVP_MD_CTX_new()) == NULL)
1324 		goto err;
1325 
1326 	if (s->internal->init_num < 0)
1327 		goto err;
1328 
1329 	CBS_init(&cbs, s->internal->init_msg, s->internal->init_num);
1330 
1331 	if (s->s3->hs.tls12.message_type != SSL3_MT_SERVER_KEY_EXCHANGE) {
1332 		/*
1333 		 * Do not skip server key exchange if this cipher suite uses
1334 		 * ephemeral keys.
1335 		 */
1336 		if (alg_k & (SSL_kDHE|SSL_kECDHE)) {
1337 			SSLerror(s, SSL_R_UNEXPECTED_MESSAGE);
1338 			al = SSL_AD_UNEXPECTED_MESSAGE;
1339 			goto fatal_err;
1340 		}
1341 
1342 		s->s3->hs.tls12.reuse_message = 1;
1343 		EVP_MD_CTX_free(md_ctx);
1344 		return (1);
1345 	}
1346 
1347 	param = CBS_data(&cbs);
1348 	param_len = CBS_len(&cbs);
1349 
1350 	if (alg_k & SSL_kDHE) {
1351 		if (!ssl3_get_server_kex_dhe(s, &cbs))
1352 			goto err;
1353 	} else if (alg_k & SSL_kECDHE) {
1354 		if (!ssl3_get_server_kex_ecdhe(s, &cbs))
1355 			goto err;
1356 	} else if (alg_k != 0) {
1357 		al = SSL_AD_UNEXPECTED_MESSAGE;
1358 		SSLerror(s, SSL_R_UNEXPECTED_MESSAGE);
1359 		goto fatal_err;
1360 	}
1361 
1362 	param_len -= CBS_len(&cbs);
1363 
1364 	/* if it was signed, check the signature */
1365 	if ((alg_a & SSL_aNULL) == 0) {
1366 		uint16_t sigalg_value = SIGALG_NONE;
1367 		const struct ssl_sigalg *sigalg;
1368 		EVP_PKEY_CTX *pctx;
1369 		EVP_PKEY *pkey = NULL;
1370 
1371 		if ((alg_a & SSL_aRSA) != 0 &&
1372 		    s->session->peer_cert_type == SSL_PKEY_RSA) {
1373 			pkey = X509_get0_pubkey(s->session->peer_cert);
1374 		} else if ((alg_a & SSL_aECDSA) != 0 &&
1375 		    s->session->peer_cert_type == SSL_PKEY_ECC) {
1376 			pkey = X509_get0_pubkey(s->session->peer_cert);
1377 		}
1378 		if (pkey == NULL) {
1379 			al = SSL_AD_ILLEGAL_PARAMETER;
1380 			SSLerror(s, SSL_R_UNKNOWN_CERTIFICATE_TYPE);
1381 			goto fatal_err;
1382 		}
1383 
1384 		if (SSL_USE_SIGALGS(s)) {
1385 			if (!CBS_get_u16(&cbs, &sigalg_value))
1386 				goto decode_err;
1387 		}
1388 		if (!CBS_get_u16_length_prefixed(&cbs, &signature))
1389 			goto decode_err;
1390 		if (CBS_len(&signature) > EVP_PKEY_size(pkey)) {
1391 			al = SSL_AD_DECODE_ERROR;
1392 			SSLerror(s, SSL_R_WRONG_SIGNATURE_LENGTH);
1393 			goto fatal_err;
1394 		}
1395 
1396 		if ((sigalg = ssl_sigalg_for_peer(s, pkey,
1397 		    sigalg_value)) == NULL) {
1398 			al = SSL_AD_DECODE_ERROR;
1399 			goto fatal_err;
1400 		}
1401 		s->s3->hs.peer_sigalg = sigalg;
1402 
1403 		if (!EVP_DigestVerifyInit(md_ctx, &pctx, sigalg->md(),
1404 		    NULL, pkey))
1405 			goto err;
1406 		if (!EVP_DigestVerifyUpdate(md_ctx, s->s3->client_random,
1407 		    SSL3_RANDOM_SIZE))
1408 			goto err;
1409 		if ((sigalg->flags & SIGALG_FLAG_RSA_PSS) &&
1410 		    (!EVP_PKEY_CTX_set_rsa_padding(pctx,
1411 		    RSA_PKCS1_PSS_PADDING) ||
1412 		    !EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, -1)))
1413 			goto err;
1414 		if (!EVP_DigestVerifyUpdate(md_ctx, s->s3->server_random,
1415 		    SSL3_RANDOM_SIZE))
1416 			goto err;
1417 		if (!EVP_DigestVerifyUpdate(md_ctx, param, param_len))
1418 			goto err;
1419 		if (EVP_DigestVerifyFinal(md_ctx, CBS_data(&signature),
1420 		    CBS_len(&signature)) <= 0) {
1421 			al = SSL_AD_DECRYPT_ERROR;
1422 			SSLerror(s, SSL_R_BAD_SIGNATURE);
1423 			goto fatal_err;
1424 		}
1425 	}
1426 
1427 	if (CBS_len(&cbs) != 0) {
1428 		al = SSL_AD_DECODE_ERROR;
1429 		SSLerror(s, SSL_R_EXTRA_DATA_IN_MESSAGE);
1430 		goto fatal_err;
1431 	}
1432 
1433 	EVP_MD_CTX_free(md_ctx);
1434 
1435 	return (1);
1436 
1437  decode_err:
1438 	al = SSL_AD_DECODE_ERROR;
1439 	SSLerror(s, SSL_R_BAD_PACKET_LENGTH);
1440 
1441  fatal_err:
1442 	ssl3_send_alert(s, SSL3_AL_FATAL, al);
1443 
1444  err:
1445 	EVP_MD_CTX_free(md_ctx);
1446 
1447 	return (-1);
1448 }
1449 
1450 int
1451 ssl3_get_certificate_request(SSL *s)
1452 {
1453 	CBS cert_request, cert_types, rdn_list;
1454 	X509_NAME *xn = NULL;
1455 	const unsigned char *q;
1456 	STACK_OF(X509_NAME) *ca_sk = NULL;
1457 	int ret;
1458 
1459 	if ((ret = ssl3_get_message(s, SSL3_ST_CR_CERT_REQ_A,
1460 	    SSL3_ST_CR_CERT_REQ_B, -1, s->internal->max_cert_list)) <= 0)
1461 		return ret;
1462 
1463 	ret = 0;
1464 
1465 	s->s3->hs.tls12.cert_request = 0;
1466 
1467 	if (s->s3->hs.tls12.message_type == SSL3_MT_SERVER_DONE) {
1468 		s->s3->hs.tls12.reuse_message = 1;
1469 		/*
1470 		 * If we get here we don't need any cached handshake records
1471 		 * as we wont be doing client auth.
1472 		 */
1473 		tls1_transcript_free(s);
1474 		return (1);
1475 	}
1476 
1477 	if (s->s3->hs.tls12.message_type != SSL3_MT_CERTIFICATE_REQUEST) {
1478 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
1479 		SSLerror(s, SSL_R_WRONG_MESSAGE_TYPE);
1480 		goto err;
1481 	}
1482 
1483 	/* TLS does not like anon-DH with client cert */
1484 	if (s->s3->hs.cipher->algorithm_auth & SSL_aNULL) {
1485 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
1486 		SSLerror(s, SSL_R_TLS_CLIENT_CERT_REQ_WITH_ANON_CIPHER);
1487 		goto err;
1488 	}
1489 
1490 	if (s->internal->init_num < 0)
1491 		goto decode_err;
1492 	CBS_init(&cert_request, s->internal->init_msg, s->internal->init_num);
1493 
1494 	if ((ca_sk = sk_X509_NAME_new(ca_dn_cmp)) == NULL) {
1495 		SSLerror(s, ERR_R_MALLOC_FAILURE);
1496 		goto err;
1497 	}
1498 
1499 	if (!CBS_get_u8_length_prefixed(&cert_request, &cert_types))
1500 		goto decode_err;
1501 
1502 	if (SSL_USE_SIGALGS(s)) {
1503 		CBS sigalgs;
1504 
1505 		if (CBS_len(&cert_request) < 2) {
1506 			SSLerror(s, SSL_R_DATA_LENGTH_TOO_LONG);
1507 			goto err;
1508 		}
1509 		if (!CBS_get_u16_length_prefixed(&cert_request, &sigalgs)) {
1510 			ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1511 			SSLerror(s, SSL_R_DATA_LENGTH_TOO_LONG);
1512 			goto err;
1513 		}
1514 		if (CBS_len(&sigalgs) % 2 != 0 || CBS_len(&sigalgs) > 64) {
1515 			ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1516 			SSLerror(s, SSL_R_SIGNATURE_ALGORITHMS_ERROR);
1517 			goto err;
1518 		}
1519 		if (!CBS_stow(&sigalgs, &s->s3->hs.sigalgs,
1520 		    &s->s3->hs.sigalgs_len))
1521 			goto err;
1522 	}
1523 
1524 	/* get the CA RDNs */
1525 	if (CBS_len(&cert_request) < 2) {
1526 		SSLerror(s, SSL_R_DATA_LENGTH_TOO_LONG);
1527 		goto err;
1528 	}
1529 
1530 	if (!CBS_get_u16_length_prefixed(&cert_request, &rdn_list) ||
1531 	    CBS_len(&cert_request) != 0) {
1532 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1533 		SSLerror(s, SSL_R_LENGTH_MISMATCH);
1534 		goto err;
1535 	}
1536 
1537 	while (CBS_len(&rdn_list) > 0) {
1538 		CBS rdn;
1539 
1540 		if (CBS_len(&rdn_list) < 2) {
1541 			SSLerror(s, SSL_R_DATA_LENGTH_TOO_LONG);
1542 			goto err;
1543 		}
1544 
1545 		if (!CBS_get_u16_length_prefixed(&rdn_list, &rdn)) {
1546 			ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1547 			SSLerror(s, SSL_R_CA_DN_TOO_LONG);
1548 			goto err;
1549 		}
1550 
1551 		q = CBS_data(&rdn);
1552 		if ((xn = d2i_X509_NAME(NULL, &q, CBS_len(&rdn))) == NULL) {
1553 			ssl3_send_alert(s, SSL3_AL_FATAL,
1554 			    SSL_AD_DECODE_ERROR);
1555 			SSLerror(s, ERR_R_ASN1_LIB);
1556 			goto err;
1557 		}
1558 
1559 		if (q != CBS_data(&rdn) + CBS_len(&rdn)) {
1560 			ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1561 			SSLerror(s, SSL_R_CA_DN_LENGTH_MISMATCH);
1562 			goto err;
1563 		}
1564 		if (!sk_X509_NAME_push(ca_sk, xn)) {
1565 			SSLerror(s, ERR_R_MALLOC_FAILURE);
1566 			goto err;
1567 		}
1568 		xn = NULL;	/* avoid free in err block */
1569 	}
1570 
1571 	/* we should setup a certificate to return.... */
1572 	s->s3->hs.tls12.cert_request = 1;
1573 	sk_X509_NAME_pop_free(s->s3->hs.tls12.ca_names, X509_NAME_free);
1574 	s->s3->hs.tls12.ca_names = ca_sk;
1575 	ca_sk = NULL;
1576 
1577 	ret = 1;
1578 	if (0) {
1579  decode_err:
1580 		SSLerror(s, SSL_R_BAD_PACKET_LENGTH);
1581 	}
1582  err:
1583 	X509_NAME_free(xn);
1584 	sk_X509_NAME_pop_free(ca_sk, X509_NAME_free);
1585 	return (ret);
1586 }
1587 
1588 static int
1589 ca_dn_cmp(const X509_NAME * const *a, const X509_NAME * const *b)
1590 {
1591 	return (X509_NAME_cmp(*a, *b));
1592 }
1593 
1594 int
1595 ssl3_get_new_session_ticket(SSL *s)
1596 {
1597 	uint32_t lifetime_hint;
1598 	CBS cbs, session_ticket;
1599 	int al, ret;
1600 
1601 	if ((ret = ssl3_get_message(s, SSL3_ST_CR_SESSION_TICKET_A,
1602 	    SSL3_ST_CR_SESSION_TICKET_B, -1, 16384)) <= 0)
1603 		return ret;
1604 
1605 	if (s->s3->hs.tls12.message_type == SSL3_MT_FINISHED) {
1606 		s->s3->hs.tls12.reuse_message = 1;
1607 		return (1);
1608 	}
1609 	if (s->s3->hs.tls12.message_type != SSL3_MT_NEWSESSION_TICKET) {
1610 		al = SSL_AD_UNEXPECTED_MESSAGE;
1611 		SSLerror(s, SSL_R_BAD_MESSAGE_TYPE);
1612 		goto fatal_err;
1613 	}
1614 
1615 	if (s->internal->init_num < 0) {
1616 		al = SSL_AD_DECODE_ERROR;
1617 		SSLerror(s, SSL_R_LENGTH_MISMATCH);
1618 		goto fatal_err;
1619 	}
1620 
1621 	CBS_init(&cbs, s->internal->init_msg, s->internal->init_num);
1622 	if (!CBS_get_u32(&cbs, &lifetime_hint) ||
1623 	    !CBS_get_u16_length_prefixed(&cbs, &session_ticket) ||
1624 	    CBS_len(&cbs) != 0) {
1625 		al = SSL_AD_DECODE_ERROR;
1626 		SSLerror(s, SSL_R_LENGTH_MISMATCH);
1627 		goto fatal_err;
1628 	}
1629 	s->session->tlsext_tick_lifetime_hint = lifetime_hint;
1630 
1631 	if (!CBS_stow(&session_ticket, &s->session->tlsext_tick,
1632 	    &s->session->tlsext_ticklen)) {
1633 		SSLerror(s, ERR_R_MALLOC_FAILURE);
1634 		goto err;
1635 	}
1636 
1637 	/*
1638 	 * There are two ways to detect a resumed ticket sesion.
1639 	 * One is to set an appropriate session ID and then the server
1640 	 * must return a match in ServerHello. This allows the normal
1641 	 * client session ID matching to work and we know much
1642 	 * earlier that the ticket has been accepted.
1643 	 *
1644 	 * The other way is to set zero length session ID when the
1645 	 * ticket is presented and rely on the handshake to determine
1646 	 * session resumption.
1647 	 *
1648 	 * We choose the former approach because this fits in with
1649 	 * assumptions elsewhere in OpenSSL. The session ID is set
1650 	 * to the SHA256 (or SHA1 is SHA256 is disabled) hash of the
1651 	 * ticket.
1652 	 */
1653 	EVP_Digest(CBS_data(&session_ticket), CBS_len(&session_ticket),
1654 	    s->session->session_id, &s->session->session_id_length,
1655 	    EVP_sha256(), NULL);
1656 
1657 	return (1);
1658 
1659  fatal_err:
1660 	ssl3_send_alert(s, SSL3_AL_FATAL, al);
1661  err:
1662 	return (-1);
1663 }
1664 
1665 int
1666 ssl3_get_cert_status(SSL *s)
1667 {
1668 	CBS cert_status, response;
1669 	uint8_t	status_type;
1670 	int al, ret;
1671 
1672 	if ((ret = ssl3_get_message(s, SSL3_ST_CR_CERT_STATUS_A,
1673 	    SSL3_ST_CR_CERT_STATUS_B, -1, 16384)) <= 0)
1674 		return ret;
1675 
1676 	if (s->s3->hs.tls12.message_type == SSL3_MT_SERVER_KEY_EXCHANGE) {
1677 		/*
1678 		 * Tell the callback the server did not send us an OSCP
1679 		 * response, and has decided to head directly to key exchange.
1680 		 */
1681 		if (s->ctx->internal->tlsext_status_cb) {
1682 			free(s->internal->tlsext_ocsp_resp);
1683 			s->internal->tlsext_ocsp_resp = NULL;
1684 			s->internal->tlsext_ocsp_resp_len = 0;
1685 
1686 			ret = s->ctx->internal->tlsext_status_cb(s,
1687 			    s->ctx->internal->tlsext_status_arg);
1688 			if (ret == 0) {
1689 				al = SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE;
1690 				SSLerror(s, SSL_R_INVALID_STATUS_RESPONSE);
1691 				goto fatal_err;
1692 			}
1693 			if (ret < 0) {
1694 				al = SSL_AD_INTERNAL_ERROR;
1695 				SSLerror(s, ERR_R_MALLOC_FAILURE);
1696 				goto fatal_err;
1697 			}
1698 		}
1699 		s->s3->hs.tls12.reuse_message = 1;
1700 		return (1);
1701 	}
1702 
1703 	if (s->s3->hs.tls12.message_type != SSL3_MT_CERTIFICATE &&
1704 	    s->s3->hs.tls12.message_type != SSL3_MT_CERTIFICATE_STATUS) {
1705 		al = SSL_AD_UNEXPECTED_MESSAGE;
1706 		SSLerror(s, SSL_R_BAD_MESSAGE_TYPE);
1707 		goto fatal_err;
1708 	}
1709 
1710 	if (s->internal->init_num < 0) {
1711 		/* need at least status type + length */
1712 		al = SSL_AD_DECODE_ERROR;
1713 		SSLerror(s, SSL_R_LENGTH_MISMATCH);
1714 		goto fatal_err;
1715 	}
1716 
1717 	CBS_init(&cert_status, s->internal->init_msg, s->internal->init_num);
1718 	if (!CBS_get_u8(&cert_status, &status_type) ||
1719 	    CBS_len(&cert_status) < 3) {
1720 		/* need at least status type + length */
1721 		al = SSL_AD_DECODE_ERROR;
1722 		SSLerror(s, SSL_R_LENGTH_MISMATCH);
1723 		goto fatal_err;
1724 	}
1725 
1726 	if (status_type != TLSEXT_STATUSTYPE_ocsp) {
1727 		al = SSL_AD_DECODE_ERROR;
1728 		SSLerror(s, SSL_R_UNSUPPORTED_STATUS_TYPE);
1729 		goto fatal_err;
1730 	}
1731 
1732 	if (!CBS_get_u24_length_prefixed(&cert_status, &response) ||
1733 	    CBS_len(&cert_status) != 0) {
1734 		al = SSL_AD_DECODE_ERROR;
1735 		SSLerror(s, SSL_R_LENGTH_MISMATCH);
1736 		goto fatal_err;
1737 	}
1738 
1739 	if (!CBS_stow(&response, &s->internal->tlsext_ocsp_resp,
1740 	    &s->internal->tlsext_ocsp_resp_len)) {
1741 		al = SSL_AD_INTERNAL_ERROR;
1742 		SSLerror(s, ERR_R_MALLOC_FAILURE);
1743 		goto fatal_err;
1744 	}
1745 
1746 	if (s->ctx->internal->tlsext_status_cb) {
1747 		int ret;
1748 		ret = s->ctx->internal->tlsext_status_cb(s,
1749 		    s->ctx->internal->tlsext_status_arg);
1750 		if (ret == 0) {
1751 			al = SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE;
1752 			SSLerror(s, SSL_R_INVALID_STATUS_RESPONSE);
1753 			goto fatal_err;
1754 		}
1755 		if (ret < 0) {
1756 			al = SSL_AD_INTERNAL_ERROR;
1757 			SSLerror(s, ERR_R_MALLOC_FAILURE);
1758 			goto fatal_err;
1759 		}
1760 	}
1761 	return (1);
1762  fatal_err:
1763 	ssl3_send_alert(s, SSL3_AL_FATAL, al);
1764 	return (-1);
1765 }
1766 
1767 int
1768 ssl3_get_server_done(SSL *s)
1769 {
1770 	int ret;
1771 
1772 	if ((ret = ssl3_get_message(s, SSL3_ST_CR_SRVR_DONE_A,
1773 	    SSL3_ST_CR_SRVR_DONE_B, SSL3_MT_SERVER_DONE,
1774 	    30 /* should be very small, like 0 :-) */)) <= 0)
1775 		return ret;
1776 
1777 	if (s->internal->init_num != 0) {
1778 		/* should contain no data */
1779 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
1780 		SSLerror(s, SSL_R_LENGTH_MISMATCH);
1781 		return -1;
1782 	}
1783 
1784 	return 1;
1785 }
1786 
1787 static int
1788 ssl3_send_client_kex_rsa(SSL *s, CBB *cbb)
1789 {
1790 	unsigned char pms[SSL_MAX_MASTER_KEY_LENGTH];
1791 	unsigned char *enc_pms = NULL;
1792 	uint16_t max_legacy_version;
1793 	EVP_PKEY *pkey;
1794 	RSA *rsa;
1795 	int ret = 0;
1796 	int enc_len;
1797 	CBB epms;
1798 
1799 	/*
1800 	 * RSA-Encrypted Premaster Secret Message - RFC 5246 section 7.4.7.1.
1801 	 */
1802 
1803 	pkey = X509_get0_pubkey(s->session->peer_cert);
1804 	if (pkey == NULL || (rsa = EVP_PKEY_get0_RSA(pkey)) == NULL) {
1805 		SSLerror(s, ERR_R_INTERNAL_ERROR);
1806 		goto err;
1807 	}
1808 
1809 	/*
1810 	 * Our maximum legacy protocol version - while RFC 5246 section 7.4.7.1
1811 	 * says "The latest (newest) version supported by the client", if we're
1812 	 * doing RSA key exchange then we have to presume that we're talking to
1813 	 * a server that does not understand the supported versions extension
1814 	 * and therefore our maximum version is that sent in the ClientHello.
1815 	 */
1816 	if (!ssl_max_legacy_version(s, &max_legacy_version))
1817 		goto err;
1818 	pms[0] = max_legacy_version >> 8;
1819 	pms[1] = max_legacy_version & 0xff;
1820 	arc4random_buf(&pms[2], sizeof(pms) - 2);
1821 
1822 	if ((enc_pms = malloc(RSA_size(rsa))) == NULL) {
1823 		SSLerror(s, ERR_R_MALLOC_FAILURE);
1824 		goto err;
1825 	}
1826 
1827 	enc_len = RSA_public_encrypt(sizeof(pms), pms, enc_pms, rsa,
1828 	    RSA_PKCS1_PADDING);
1829 	if (enc_len <= 0) {
1830 		SSLerror(s, SSL_R_BAD_RSA_ENCRYPT);
1831 		goto err;
1832 	}
1833 
1834 	if (!CBB_add_u16_length_prefixed(cbb, &epms))
1835 		goto err;
1836 	if (!CBB_add_bytes(&epms, enc_pms, enc_len))
1837 		goto err;
1838 	if (!CBB_flush(cbb))
1839 		goto err;
1840 
1841 	if (!tls12_derive_master_secret(s, pms, sizeof(pms)))
1842 		goto err;
1843 
1844 	ret = 1;
1845 
1846  err:
1847 	explicit_bzero(pms, sizeof(pms));
1848 	free(enc_pms);
1849 
1850 	return ret;
1851 }
1852 
1853 static int
1854 ssl3_send_client_kex_dhe(SSL *s, CBB *cbb)
1855 {
1856 	uint8_t *key = NULL;
1857 	size_t key_len = 0;
1858 	int ret = 0;
1859 
1860 	/* Ensure that we have an ephemeral key from the server for DHE. */
1861 	if (s->s3->hs.key_share == NULL) {
1862 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
1863 		SSLerror(s, SSL_R_UNABLE_TO_FIND_DH_PARAMETERS);
1864 		goto err;
1865 	}
1866 
1867 	if (!tls_key_share_generate(s->s3->hs.key_share))
1868 		goto err;
1869 	if (!tls_key_share_public(s->s3->hs.key_share, cbb))
1870 		goto err;
1871 	if (!tls_key_share_derive(s->s3->hs.key_share, &key, &key_len))
1872 		goto err;
1873 
1874 	if (!tls12_derive_master_secret(s, key, key_len))
1875 		goto err;
1876 
1877 	ret = 1;
1878 
1879  err:
1880 	freezero(key, key_len);
1881 
1882 	return ret;
1883 }
1884 
1885 static int
1886 ssl3_send_client_kex_ecdhe(SSL *s, CBB *cbb)
1887 {
1888 	uint8_t *key = NULL;
1889 	size_t key_len = 0;
1890 	CBB public;
1891 	int ret = 0;
1892 
1893 	/* Ensure that we have an ephemeral key for ECDHE. */
1894 	if (s->s3->hs.key_share == NULL) {
1895 		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
1896 		SSLerror(s, ERR_R_INTERNAL_ERROR);
1897 		goto err;
1898 	}
1899 
1900 	if (!tls_key_share_generate(s->s3->hs.key_share))
1901 		goto err;
1902 
1903 	if (!CBB_add_u8_length_prefixed(cbb, &public))
1904 		return 0;
1905 	if (!tls_key_share_public(s->s3->hs.key_share, &public))
1906 		goto err;
1907 	if (!CBB_flush(cbb))
1908 		goto err;
1909 
1910 	if (!tls_key_share_derive(s->s3->hs.key_share, &key, &key_len))
1911 		goto err;
1912 
1913 	if (!tls12_derive_master_secret(s, key, key_len))
1914 		goto err;
1915 
1916 	ret = 1;
1917 
1918  err:
1919 	freezero(key, key_len);
1920 
1921 	return ret;
1922 }
1923 
1924 static int
1925 ssl3_send_client_kex_gost(SSL *s, CBB *cbb)
1926 {
1927 	unsigned char premaster_secret[32], shared_ukm[32], tmp[256];
1928 	EVP_PKEY_CTX *pkey_ctx = NULL;
1929 	EVP_MD_CTX *ukm_hash = NULL;
1930 	EVP_PKEY *pkey;
1931 	size_t msglen;
1932 	unsigned int md_len;
1933 	CBB gostblob;
1934 	int nid;
1935 	int ret = 0;
1936 
1937 	/* Get server sertificate PKEY and create ctx from it */
1938 	pkey = X509_get0_pubkey(s->session->peer_cert);
1939 	if (pkey == NULL || s->session->peer_cert_type != SSL_PKEY_GOST01) {
1940 		SSLerror(s, SSL_R_NO_GOST_CERTIFICATE_SENT_BY_PEER);
1941 		goto err;
1942 	}
1943 	if ((pkey_ctx = EVP_PKEY_CTX_new(pkey, NULL)) == NULL) {
1944 		SSLerror(s, ERR_R_MALLOC_FAILURE);
1945 		goto err;
1946 	}
1947 
1948 	/*
1949 	 * If we have send a certificate, and certificate key parameters match
1950 	 * those of server certificate, use certificate key for key exchange.
1951 	 * Otherwise, generate ephemeral key pair.
1952 	 */
1953 	if (EVP_PKEY_encrypt_init(pkey_ctx) <= 0)
1954 		goto err;
1955 
1956 	/* Generate session key. */
1957 	arc4random_buf(premaster_secret, sizeof(premaster_secret));
1958 
1959 	/*
1960 	 * If we have client certificate, use its secret as peer key.
1961 	 * XXX - this presumably lacks PFS.
1962 	 */
1963 	if (s->s3->hs.tls12.cert_request != 0 &&
1964 	    s->cert->key->privatekey != NULL) {
1965 		if (EVP_PKEY_derive_set_peer(pkey_ctx,
1966 		    s->cert->key->privatekey) <=0) {
1967 			/*
1968 			 * If there was an error - just ignore it.
1969 			 * Ephemeral key would be used.
1970 			 */
1971 			ERR_clear_error();
1972 		}
1973 	}
1974 
1975 	/*
1976 	 * Compute shared IV and store it in algorithm-specific context data.
1977 	 */
1978 	if ((ukm_hash = EVP_MD_CTX_new()) == NULL) {
1979 		SSLerror(s, ERR_R_MALLOC_FAILURE);
1980 		goto err;
1981 	}
1982 
1983 	/* XXX check handshake hash instead. */
1984 	if (s->s3->hs.cipher->algorithm2 & SSL_HANDSHAKE_MAC_GOST94)
1985 		nid = NID_id_GostR3411_94;
1986 	else
1987 		nid = NID_id_tc26_gost3411_2012_256;
1988 	if (!EVP_DigestInit(ukm_hash, EVP_get_digestbynid(nid)))
1989 		goto err;
1990 	if (!EVP_DigestUpdate(ukm_hash, s->s3->client_random, SSL3_RANDOM_SIZE))
1991 		goto err;
1992 	if (!EVP_DigestUpdate(ukm_hash, s->s3->server_random, SSL3_RANDOM_SIZE))
1993 		goto err;
1994 	if (!EVP_DigestFinal_ex(ukm_hash, shared_ukm, &md_len))
1995 		goto err;
1996 	if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, EVP_PKEY_OP_ENCRYPT,
1997 	    EVP_PKEY_CTRL_SET_IV, 8, shared_ukm) < 0) {
1998 		SSLerror(s, SSL_R_LIBRARY_BUG);
1999 		goto err;
2000 	}
2001 
2002 	/*
2003 	 * Make GOST keytransport blob message, encapsulate it into sequence.
2004 	 */
2005 	msglen = 255;
2006 	if (EVP_PKEY_encrypt(pkey_ctx, tmp, &msglen, premaster_secret,
2007 	    sizeof(premaster_secret)) < 0) {
2008 		SSLerror(s, SSL_R_LIBRARY_BUG);
2009 		goto err;
2010 	}
2011 
2012 	if (!CBB_add_asn1(cbb, &gostblob, CBS_ASN1_SEQUENCE))
2013 		goto err;
2014 	if (!CBB_add_bytes(&gostblob, tmp, msglen))
2015 		goto err;
2016 	if (!CBB_flush(cbb))
2017 		goto err;
2018 
2019 	/* Check if pubkey from client certificate was used. */
2020 	if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, -1, EVP_PKEY_CTRL_PEER_KEY, 2,
2021 	    NULL) > 0)
2022 		s->s3->flags |= TLS1_FLAGS_SKIP_CERT_VERIFY;
2023 
2024 	if (!tls12_derive_master_secret(s, premaster_secret, 32))
2025 		goto err;
2026 
2027 	ret = 1;
2028 
2029  err:
2030 	explicit_bzero(premaster_secret, sizeof(premaster_secret));
2031 	EVP_PKEY_CTX_free(pkey_ctx);
2032 	EVP_MD_CTX_free(ukm_hash);
2033 
2034 	return ret;
2035 }
2036 
2037 int
2038 ssl3_send_client_key_exchange(SSL *s)
2039 {
2040 	unsigned long alg_k;
2041 	CBB cbb, kex;
2042 
2043 	memset(&cbb, 0, sizeof(cbb));
2044 
2045 	if (s->s3->hs.state == SSL3_ST_CW_KEY_EXCH_A) {
2046 		alg_k = s->s3->hs.cipher->algorithm_mkey;
2047 
2048 		if (!ssl3_handshake_msg_start(s, &cbb, &kex,
2049 		    SSL3_MT_CLIENT_KEY_EXCHANGE))
2050 			goto err;
2051 
2052 		if (alg_k & SSL_kRSA) {
2053 			if (!ssl3_send_client_kex_rsa(s, &kex))
2054 				goto err;
2055 		} else if (alg_k & SSL_kDHE) {
2056 			if (!ssl3_send_client_kex_dhe(s, &kex))
2057 				goto err;
2058 		} else if (alg_k & SSL_kECDHE) {
2059 			if (!ssl3_send_client_kex_ecdhe(s, &kex))
2060 				goto err;
2061 		} else if (alg_k & SSL_kGOST) {
2062 			if (!ssl3_send_client_kex_gost(s, &kex))
2063 				goto err;
2064 		} else {
2065 			ssl3_send_alert(s, SSL3_AL_FATAL,
2066 			    SSL_AD_HANDSHAKE_FAILURE);
2067 			SSLerror(s, ERR_R_INTERNAL_ERROR);
2068 			goto err;
2069 		}
2070 
2071 		if (!ssl3_handshake_msg_finish(s, &cbb))
2072 			goto err;
2073 
2074 		s->s3->hs.state = SSL3_ST_CW_KEY_EXCH_B;
2075 	}
2076 
2077 	/* SSL3_ST_CW_KEY_EXCH_B */
2078 	return (ssl3_handshake_write(s));
2079 
2080  err:
2081 	CBB_cleanup(&cbb);
2082 
2083 	return (-1);
2084 }
2085 
2086 static int
2087 ssl3_send_client_verify_sigalgs(SSL *s, EVP_PKEY *pkey,
2088     const struct ssl_sigalg *sigalg, CBB *cert_verify)
2089 {
2090 	CBB cbb_signature;
2091 	EVP_PKEY_CTX *pctx = NULL;
2092 	EVP_MD_CTX *mctx = NULL;
2093 	const unsigned char *hdata;
2094 	unsigned char *signature = NULL;
2095 	size_t signature_len, hdata_len;
2096 	int ret = 0;
2097 
2098 	if ((mctx = EVP_MD_CTX_new()) == NULL)
2099 		goto err;
2100 
2101 	if (!tls1_transcript_data(s, &hdata, &hdata_len)) {
2102 		SSLerror(s, ERR_R_INTERNAL_ERROR);
2103 		goto err;
2104 	}
2105 	if (!EVP_DigestSignInit(mctx, &pctx, sigalg->md(), NULL, pkey)) {
2106 		SSLerror(s, ERR_R_EVP_LIB);
2107 		goto err;
2108 	}
2109 	if (sigalg->key_type == EVP_PKEY_GOSTR01 &&
2110 	    EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_SIGN,
2111 	    EVP_PKEY_CTRL_GOST_SIG_FORMAT, GOST_SIG_FORMAT_RS_LE, NULL) <= 0) {
2112 		SSLerror(s, ERR_R_EVP_LIB);
2113 		goto err;
2114 	}
2115 	if ((sigalg->flags & SIGALG_FLAG_RSA_PSS) &&
2116 	    (!EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) ||
2117 	    !EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, -1))) {
2118 		SSLerror(s, ERR_R_EVP_LIB);
2119 		goto err;
2120 	}
2121 	if (!EVP_DigestSignUpdate(mctx, hdata, hdata_len)) {
2122 		SSLerror(s, ERR_R_EVP_LIB);
2123 		goto err;
2124 	}
2125 	if (!EVP_DigestSignFinal(mctx, NULL, &signature_len) ||
2126 	    signature_len == 0) {
2127 		SSLerror(s, ERR_R_EVP_LIB);
2128 		goto err;
2129 	}
2130 	if ((signature = calloc(1, signature_len)) == NULL) {
2131 		SSLerror(s, ERR_R_MALLOC_FAILURE);
2132 		goto err;
2133 	}
2134 	if (!EVP_DigestSignFinal(mctx, signature, &signature_len)) {
2135 		SSLerror(s, ERR_R_EVP_LIB);
2136 		goto err;
2137 	}
2138 
2139 	if (!CBB_add_u16(cert_verify, sigalg->value))
2140 		goto err;
2141 	if (!CBB_add_u16_length_prefixed(cert_verify, &cbb_signature))
2142 		goto err;
2143 	if (!CBB_add_bytes(&cbb_signature, signature, signature_len))
2144 		goto err;
2145 	if (!CBB_flush(cert_verify))
2146 		goto err;
2147 
2148 	ret = 1;
2149 
2150  err:
2151 	EVP_MD_CTX_free(mctx);
2152 	free(signature);
2153 	return ret;
2154 }
2155 
2156 static int
2157 ssl3_send_client_verify_rsa(SSL *s, EVP_PKEY *pkey, CBB *cert_verify)
2158 {
2159 	CBB cbb_signature;
2160 	RSA *rsa;
2161 	unsigned char data[EVP_MAX_MD_SIZE];
2162 	unsigned char *signature = NULL;
2163 	unsigned int signature_len;
2164 	size_t data_len;
2165 	int ret = 0;
2166 
2167 	if (!tls1_transcript_hash_value(s, data, sizeof(data), &data_len))
2168 		goto err;
2169 	if ((signature = calloc(1, EVP_PKEY_size(pkey))) == NULL)
2170 		goto err;
2171 	if ((rsa = EVP_PKEY_get0_RSA(pkey)) == NULL)
2172 		goto err;
2173 	if (RSA_sign(NID_md5_sha1, data, data_len, signature, &signature_len,
2174 	    rsa) <= 0 ) {
2175 		SSLerror(s, ERR_R_RSA_LIB);
2176 		goto err;
2177 	}
2178 
2179 	if (!CBB_add_u16_length_prefixed(cert_verify, &cbb_signature))
2180 		goto err;
2181 	if (!CBB_add_bytes(&cbb_signature, signature, signature_len))
2182 		goto err;
2183 	if (!CBB_flush(cert_verify))
2184 		goto err;
2185 
2186 	ret = 1;
2187  err:
2188 	free(signature);
2189 	return ret;
2190 }
2191 
2192 static int
2193 ssl3_send_client_verify_ec(SSL *s, EVP_PKEY *pkey, CBB *cert_verify)
2194 {
2195 	CBB cbb_signature;
2196 	EC_KEY *eckey;
2197 	unsigned char data[EVP_MAX_MD_SIZE];
2198 	unsigned char *signature = NULL;
2199 	unsigned int signature_len;
2200 	int ret = 0;
2201 
2202 	if (!tls1_transcript_hash_value(s, data, sizeof(data), NULL))
2203 		goto err;
2204 	if ((signature = calloc(1, EVP_PKEY_size(pkey))) == NULL)
2205 		goto err;
2206 	if ((eckey = EVP_PKEY_get0_EC_KEY(pkey)) == NULL)
2207 		goto err;
2208 	if (!ECDSA_sign(0, &data[MD5_DIGEST_LENGTH], SHA_DIGEST_LENGTH,
2209 	    signature, &signature_len, eckey)) {
2210 		SSLerror(s, ERR_R_ECDSA_LIB);
2211 		goto err;
2212 	}
2213 
2214 	if (!CBB_add_u16_length_prefixed(cert_verify, &cbb_signature))
2215 		goto err;
2216 	if (!CBB_add_bytes(&cbb_signature, signature, signature_len))
2217 		goto err;
2218 	if (!CBB_flush(cert_verify))
2219 		goto err;
2220 
2221 	ret = 1;
2222  err:
2223 	free(signature);
2224 	return ret;
2225 }
2226 
2227 #ifndef OPENSSL_NO_GOST
2228 static int
2229 ssl3_send_client_verify_gost(SSL *s, EVP_PKEY *pkey, CBB *cert_verify)
2230 {
2231 	CBB cbb_signature;
2232 	EVP_MD_CTX *mctx;
2233 	EVP_PKEY_CTX *pctx;
2234 	const EVP_MD *md;
2235 	const unsigned char *hdata;
2236 	unsigned char *signature = NULL;
2237 	size_t signature_len;
2238 	size_t hdata_len;
2239 	int nid;
2240 	int ret = 0;
2241 
2242 	if ((mctx = EVP_MD_CTX_new()) == NULL)
2243 		goto err;
2244 
2245 	if (!tls1_transcript_data(s, &hdata, &hdata_len)) {
2246 		SSLerror(s, ERR_R_INTERNAL_ERROR);
2247 		goto err;
2248 	}
2249 	if (!EVP_PKEY_get_default_digest_nid(pkey, &nid) ||
2250 	    (md = EVP_get_digestbynid(nid)) == NULL) {
2251 		SSLerror(s, ERR_R_EVP_LIB);
2252 		goto err;
2253 	}
2254 	if (!EVP_DigestSignInit(mctx, &pctx, md, NULL, pkey)) {
2255 		SSLerror(s, ERR_R_EVP_LIB);
2256 		goto err;
2257 	}
2258 	if (EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_SIGN,
2259 	    EVP_PKEY_CTRL_GOST_SIG_FORMAT, GOST_SIG_FORMAT_RS_LE, NULL) <= 0) {
2260 		SSLerror(s, ERR_R_EVP_LIB);
2261 		goto err;
2262 	}
2263 	if (!EVP_DigestSignUpdate(mctx, hdata, hdata_len)) {
2264 		SSLerror(s, ERR_R_EVP_LIB);
2265 		goto err;
2266 	}
2267 	if (!EVP_DigestSignFinal(mctx, NULL, &signature_len) ||
2268 	    signature_len == 0) {
2269 		SSLerror(s, ERR_R_EVP_LIB);
2270 		goto err;
2271 	}
2272 	if ((signature = calloc(1, signature_len)) == NULL) {
2273 		SSLerror(s, ERR_R_MALLOC_FAILURE);
2274 		goto err;
2275 	}
2276 	if (!EVP_DigestSignFinal(mctx, signature, &signature_len)) {
2277 		SSLerror(s, ERR_R_EVP_LIB);
2278 		goto err;
2279 	}
2280 
2281 	if (!CBB_add_u16_length_prefixed(cert_verify, &cbb_signature))
2282 		goto err;
2283 	if (!CBB_add_bytes(&cbb_signature, signature, signature_len))
2284 		goto err;
2285 	if (!CBB_flush(cert_verify))
2286 		goto err;
2287 
2288 	ret = 1;
2289  err:
2290 	EVP_MD_CTX_free(mctx);
2291 	free(signature);
2292 	return ret;
2293 }
2294 #endif
2295 
2296 int
2297 ssl3_send_client_verify(SSL *s)
2298 {
2299 	const struct ssl_sigalg *sigalg;
2300 	CBB cbb, cert_verify;
2301 	EVP_PKEY *pkey;
2302 
2303 	memset(&cbb, 0, sizeof(cbb));
2304 
2305 	if (s->s3->hs.state == SSL3_ST_CW_CERT_VRFY_A) {
2306 		if (!ssl3_handshake_msg_start(s, &cbb, &cert_verify,
2307 		    SSL3_MT_CERTIFICATE_VERIFY))
2308 			goto err;
2309 
2310 		pkey = s->cert->key->privatekey;
2311 		if ((sigalg = ssl_sigalg_select(s, pkey)) == NULL) {
2312 			SSLerror(s, SSL_R_SIGNATURE_ALGORITHMS_ERROR);
2313 			goto err;
2314 		}
2315 		s->s3->hs.our_sigalg = sigalg;
2316 
2317 		/*
2318 		 * For TLS v1.2 send signature algorithm and signature using
2319 		 * agreed digest and cached handshake records.
2320 		 */
2321 		if (SSL_USE_SIGALGS(s)) {
2322 			if (!ssl3_send_client_verify_sigalgs(s, pkey, sigalg,
2323 			    &cert_verify))
2324 				goto err;
2325 		} else if (EVP_PKEY_id(pkey) == EVP_PKEY_RSA) {
2326 			if (!ssl3_send_client_verify_rsa(s, pkey, &cert_verify))
2327 				goto err;
2328 		} else if (EVP_PKEY_id(pkey) == EVP_PKEY_EC) {
2329 			if (!ssl3_send_client_verify_ec(s, pkey, &cert_verify))
2330 				goto err;
2331 #ifndef OPENSSL_NO_GOST
2332 		} else if (EVP_PKEY_id(pkey) == NID_id_GostR3410_94 ||
2333 		    EVP_PKEY_id(pkey) == NID_id_GostR3410_2001) {
2334 			if (!ssl3_send_client_verify_gost(s, pkey, &cert_verify))
2335 				goto err;
2336 #endif
2337 		} else {
2338 			SSLerror(s, ERR_R_INTERNAL_ERROR);
2339 			goto err;
2340 		}
2341 
2342 		tls1_transcript_free(s);
2343 
2344 		if (!ssl3_handshake_msg_finish(s, &cbb))
2345 			goto err;
2346 
2347 		s->s3->hs.state = SSL3_ST_CW_CERT_VRFY_B;
2348 	}
2349 
2350 	return (ssl3_handshake_write(s));
2351 
2352  err:
2353 	CBB_cleanup(&cbb);
2354 
2355 	return (-1);
2356 }
2357 
2358 int
2359 ssl3_send_client_certificate(SSL *s)
2360 {
2361 	EVP_PKEY *pkey = NULL;
2362 	X509 *x509 = NULL;
2363 	CBB cbb, client_cert;
2364 	int i;
2365 
2366 	memset(&cbb, 0, sizeof(cbb));
2367 
2368 	if (s->s3->hs.state == SSL3_ST_CW_CERT_A) {
2369 		if (s->cert->key->x509 == NULL ||
2370 		    s->cert->key->privatekey == NULL)
2371 			s->s3->hs.state = SSL3_ST_CW_CERT_B;
2372 		else
2373 			s->s3->hs.state = SSL3_ST_CW_CERT_C;
2374 	}
2375 
2376 	/* We need to get a client cert */
2377 	if (s->s3->hs.state == SSL3_ST_CW_CERT_B) {
2378 		/*
2379 		 * If we get an error, we need to
2380 		 * ssl->internal->rwstate = SSL_X509_LOOKUP; return(-1);
2381 		 * We then get retried later.
2382 		 */
2383 		i = ssl_do_client_cert_cb(s, &x509, &pkey);
2384 		if (i < 0) {
2385 			s->internal->rwstate = SSL_X509_LOOKUP;
2386 			return (-1);
2387 		}
2388 		s->internal->rwstate = SSL_NOTHING;
2389 		if ((i == 1) && (pkey != NULL) && (x509 != NULL)) {
2390 			s->s3->hs.state = SSL3_ST_CW_CERT_B;
2391 			if (!SSL_use_certificate(s, x509) ||
2392 			    !SSL_use_PrivateKey(s, pkey))
2393 				i = 0;
2394 		} else if (i == 1) {
2395 			i = 0;
2396 			SSLerror(s, SSL_R_BAD_DATA_RETURNED_BY_CALLBACK);
2397 		}
2398 
2399 		X509_free(x509);
2400 		EVP_PKEY_free(pkey);
2401 		if (i == 0) {
2402 			s->s3->hs.tls12.cert_request = 2;
2403 
2404 			/* There is no client certificate to verify. */
2405 			tls1_transcript_free(s);
2406 		}
2407 
2408 		/* Ok, we have a cert */
2409 		s->s3->hs.state = SSL3_ST_CW_CERT_C;
2410 	}
2411 
2412 	if (s->s3->hs.state == SSL3_ST_CW_CERT_C) {
2413 		if (!ssl3_handshake_msg_start(s, &cbb, &client_cert,
2414 		    SSL3_MT_CERTIFICATE))
2415 			goto err;
2416 		if (!ssl3_output_cert_chain(s, &client_cert,
2417 		    (s->s3->hs.tls12.cert_request == 2) ? NULL : s->cert->key))
2418 			goto err;
2419 		if (!ssl3_handshake_msg_finish(s, &cbb))
2420 			goto err;
2421 
2422 		s->s3->hs.state = SSL3_ST_CW_CERT_D;
2423 	}
2424 
2425 	/* SSL3_ST_CW_CERT_D */
2426 	return (ssl3_handshake_write(s));
2427 
2428  err:
2429 	CBB_cleanup(&cbb);
2430 
2431 	return (0);
2432 }
2433 
2434 #define has_bits(i,m)	(((i)&(m)) == (m))
2435 
2436 int
2437 ssl3_check_cert_and_algorithm(SSL *s)
2438 {
2439 	long alg_k, alg_a;
2440 	int nid = NID_undef;
2441 	int i;
2442 
2443 	alg_k = s->s3->hs.cipher->algorithm_mkey;
2444 	alg_a = s->s3->hs.cipher->algorithm_auth;
2445 
2446 	/* We don't have a certificate. */
2447 	if (alg_a & SSL_aNULL)
2448 		return (1);
2449 
2450 	if (s->s3->hs.key_share != NULL)
2451 		nid = tls_key_share_nid(s->s3->hs.key_share);
2452 
2453 	/* This is the passed certificate. */
2454 
2455 	if (s->session->peer_cert_type == SSL_PKEY_ECC) {
2456 		if (!ssl_check_srvr_ecc_cert_and_alg(s, s->session->peer_cert)) {
2457 			SSLerror(s, SSL_R_BAD_ECC_CERT);
2458 			goto fatal_err;
2459 		}
2460 		return (1);
2461 	}
2462 
2463 	i = X509_certificate_type(s->session->peer_cert, NULL);
2464 
2465 	/* Check that we have a certificate if we require one. */
2466 	if ((alg_a & SSL_aRSA) && !has_bits(i, EVP_PK_RSA|EVP_PKT_SIGN)) {
2467 		SSLerror(s, SSL_R_MISSING_RSA_SIGNING_CERT);
2468 		goto fatal_err;
2469 	}
2470 	if ((alg_k & SSL_kRSA) && !has_bits(i, EVP_PK_RSA|EVP_PKT_ENC)) {
2471 		SSLerror(s, SSL_R_MISSING_RSA_ENCRYPTING_CERT);
2472 		goto fatal_err;
2473 	}
2474 	if ((alg_k & SSL_kDHE) &&
2475 	    !(has_bits(i, EVP_PK_DH|EVP_PKT_EXCH) || (nid == NID_dhKeyAgreement))) {
2476 		SSLerror(s, SSL_R_MISSING_DH_KEY);
2477 		goto fatal_err;
2478 	}
2479 
2480 	return (1);
2481 
2482  fatal_err:
2483 	ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
2484 
2485 	return (0);
2486 }
2487 
2488 /*
2489  * Check to see if handshake is full or resumed. Usually this is just a
2490  * case of checking to see if a cache hit has occurred. In the case of
2491  * session tickets we have to check the next message to be sure.
2492  */
2493 
2494 int
2495 ssl3_check_finished(SSL *s)
2496 {
2497 	int ret;
2498 
2499 	/* If we have no ticket it cannot be a resumed session. */
2500 	if (!s->session->tlsext_tick)
2501 		return (1);
2502 	/* this function is called when we really expect a Certificate
2503 	 * message, so permit appropriate message length */
2504 	if ((ret = ssl3_get_message(s, SSL3_ST_CR_CERT_A,
2505 	    SSL3_ST_CR_CERT_B, -1, s->internal->max_cert_list)) <= 0)
2506 		return ret;
2507 
2508 	s->s3->hs.tls12.reuse_message = 1;
2509 	if ((s->s3->hs.tls12.message_type == SSL3_MT_FINISHED) ||
2510 	    (s->s3->hs.tls12.message_type == SSL3_MT_NEWSESSION_TICKET))
2511 		return (2);
2512 
2513 	return (1);
2514 }
2515 
2516 int
2517 ssl_do_client_cert_cb(SSL *s, X509 **px509, EVP_PKEY **ppkey)
2518 {
2519 	int	i = 0;
2520 
2521 #ifndef OPENSSL_NO_ENGINE
2522 	if (s->ctx->internal->client_cert_engine) {
2523 		i = ENGINE_load_ssl_client_cert(
2524 		    s->ctx->internal->client_cert_engine, s,
2525 		    SSL_get_client_CA_list(s), px509, ppkey, NULL, NULL, NULL);
2526 		if (i != 0)
2527 			return (i);
2528 	}
2529 #endif
2530 	if (s->ctx->internal->client_cert_cb)
2531 		i = s->ctx->internal->client_cert_cb(s, px509, ppkey);
2532 	return (i);
2533 }
2534