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[thirdparty/openssl.git] / ssl / statem / statem_srvr.c
1 /*
2 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
3 * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
4 * Copyright 2005 Nokia. All rights reserved.
5 *
6 * Licensed under the OpenSSL license (the "License"). You may not use
7 * this file except in compliance with the License. You can obtain a copy
8 * in the file LICENSE in the source distribution or at
9 * https://www.openssl.org/source/license.html
10 */
11
12 #include <stdio.h>
13 #include "../ssl_locl.h"
14 #include "statem_locl.h"
15 #include "internal/constant_time_locl.h"
16 #include <openssl/buffer.h>
17 #include <openssl/rand.h>
18 #include <openssl/objects.h>
19 #include <openssl/evp.h>
20 #include <openssl/hmac.h>
21 #include <openssl/x509.h>
22 #include <openssl/dh.h>
23 #include <openssl/bn.h>
24 #include <openssl/md5.h>
25
26 static int tls_construct_encrypted_extensions(SSL *s, WPACKET *pkt);
27 static int tls_construct_hello_retry_request(SSL *s, WPACKET *pkt);
28
29 /*
30 * ossl_statem_server13_read_transition() encapsulates the logic for the allowed
31 * handshake state transitions when a TLSv1.3 server is reading messages from
32 * the client. The message type that the client has sent is provided in |mt|.
33 * The current state is in |s->statem.hand_state|.
34 *
35 * Return values are 1 for success (transition allowed) and 0 on error
36 * (transition not allowed)
37 */
38 static int ossl_statem_server13_read_transition(SSL *s, int mt)
39 {
40 OSSL_STATEM *st = &s->statem;
41
42 /*
43 * Note: There is no case for TLS_ST_BEFORE because at that stage we have
44 * not negotiated TLSv1.3 yet, so that case is handled by
45 * ossl_statem_server_read_transition()
46 */
47 switch (st->hand_state) {
48 default:
49 break;
50
51 case TLS_ST_EARLY_DATA:
52 if (s->hello_retry_request) {
53 if (mt == SSL3_MT_CLIENT_HELLO) {
54 st->hand_state = TLS_ST_SR_CLNT_HELLO;
55 return 1;
56 }
57 break;
58 } else if (s->ext.early_data == SSL_EARLY_DATA_ACCEPTED) {
59 if (mt == SSL3_MT_END_OF_EARLY_DATA) {
60 st->hand_state = TLS_ST_SR_END_OF_EARLY_DATA;
61 return 1;
62 }
63 break;
64 }
65 /* Fall through */
66
67 case TLS_ST_SR_END_OF_EARLY_DATA:
68 case TLS_ST_SW_FINISHED:
69 if (s->s3->tmp.cert_request) {
70 if (mt == SSL3_MT_CERTIFICATE) {
71 st->hand_state = TLS_ST_SR_CERT;
72 return 1;
73 }
74 } else {
75 if (mt == SSL3_MT_FINISHED) {
76 st->hand_state = TLS_ST_SR_FINISHED;
77 return 1;
78 }
79 }
80 break;
81
82 case TLS_ST_SR_CERT:
83 if (s->session->peer == NULL) {
84 if (mt == SSL3_MT_FINISHED) {
85 st->hand_state = TLS_ST_SR_FINISHED;
86 return 1;
87 }
88 } else {
89 if (mt == SSL3_MT_CERTIFICATE_VERIFY) {
90 st->hand_state = TLS_ST_SR_CERT_VRFY;
91 return 1;
92 }
93 }
94 break;
95
96 case TLS_ST_SR_CERT_VRFY:
97 if (mt == SSL3_MT_FINISHED) {
98 st->hand_state = TLS_ST_SR_FINISHED;
99 return 1;
100 }
101 break;
102
103 case TLS_ST_OK:
104 /*
105 * Its never ok to start processing handshake messages in the middle of
106 * early data (i.e. before we've received the end of early data alert)
107 */
108 if (s->early_data_state == SSL_EARLY_DATA_READING)
109 break;
110 if (mt == SSL3_MT_KEY_UPDATE) {
111 st->hand_state = TLS_ST_SR_KEY_UPDATE;
112 return 1;
113 }
114 break;
115 }
116
117 /* No valid transition found */
118 return 0;
119 }
120
121 /*
122 * ossl_statem_server_read_transition() encapsulates the logic for the allowed
123 * handshake state transitions when the server is reading messages from the
124 * client. The message type that the client has sent is provided in |mt|. The
125 * current state is in |s->statem.hand_state|.
126 *
127 * Return values are 1 for success (transition allowed) and 0 on error
128 * (transition not allowed)
129 */
130 int ossl_statem_server_read_transition(SSL *s, int mt)
131 {
132 OSSL_STATEM *st = &s->statem;
133
134 if (SSL_IS_TLS13(s)) {
135 if (!ossl_statem_server13_read_transition(s, mt))
136 goto err;
137 return 1;
138 }
139
140 switch (st->hand_state) {
141 default:
142 break;
143
144 case TLS_ST_BEFORE:
145 case TLS_ST_OK:
146 case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
147 if (mt == SSL3_MT_CLIENT_HELLO) {
148 st->hand_state = TLS_ST_SR_CLNT_HELLO;
149 return 1;
150 }
151 break;
152
153 case TLS_ST_SW_SRVR_DONE:
154 /*
155 * If we get a CKE message after a ServerDone then either
156 * 1) We didn't request a Certificate
157 * OR
158 * 2) If we did request one then
159 * a) We allow no Certificate to be returned
160 * AND
161 * b) We are running SSL3 (in TLS1.0+ the client must return a 0
162 * list if we requested a certificate)
163 */
164 if (mt == SSL3_MT_CLIENT_KEY_EXCHANGE) {
165 if (s->s3->tmp.cert_request) {
166 if (s->version == SSL3_VERSION) {
167 if ((s->verify_mode & SSL_VERIFY_PEER)
168 && (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) {
169 /*
170 * This isn't an unexpected message as such - we're just
171 * not going to accept it because we require a client
172 * cert.
173 */
174 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
175 SSL_F_OSSL_STATEM_SERVER_READ_TRANSITION,
176 SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE);
177 return 0;
178 }
179 st->hand_state = TLS_ST_SR_KEY_EXCH;
180 return 1;
181 }
182 } else {
183 st->hand_state = TLS_ST_SR_KEY_EXCH;
184 return 1;
185 }
186 } else if (s->s3->tmp.cert_request) {
187 if (mt == SSL3_MT_CERTIFICATE) {
188 st->hand_state = TLS_ST_SR_CERT;
189 return 1;
190 }
191 }
192 break;
193
194 case TLS_ST_SR_CERT:
195 if (mt == SSL3_MT_CLIENT_KEY_EXCHANGE) {
196 st->hand_state = TLS_ST_SR_KEY_EXCH;
197 return 1;
198 }
199 break;
200
201 case TLS_ST_SR_KEY_EXCH:
202 /*
203 * We should only process a CertificateVerify message if we have
204 * received a Certificate from the client. If so then |s->session->peer|
205 * will be non NULL. In some instances a CertificateVerify message is
206 * not required even if the peer has sent a Certificate (e.g. such as in
207 * the case of static DH). In that case |st->no_cert_verify| should be
208 * set.
209 */
210 if (s->session->peer == NULL || st->no_cert_verify) {
211 if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
212 /*
213 * For the ECDH ciphersuites when the client sends its ECDH
214 * pub key in a certificate, the CertificateVerify message is
215 * not sent. Also for GOST ciphersuites when the client uses
216 * its key from the certificate for key exchange.
217 */
218 st->hand_state = TLS_ST_SR_CHANGE;
219 return 1;
220 }
221 } else {
222 if (mt == SSL3_MT_CERTIFICATE_VERIFY) {
223 st->hand_state = TLS_ST_SR_CERT_VRFY;
224 return 1;
225 }
226 }
227 break;
228
229 case TLS_ST_SR_CERT_VRFY:
230 if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
231 st->hand_state = TLS_ST_SR_CHANGE;
232 return 1;
233 }
234 break;
235
236 case TLS_ST_SR_CHANGE:
237 #ifndef OPENSSL_NO_NEXTPROTONEG
238 if (s->s3->npn_seen) {
239 if (mt == SSL3_MT_NEXT_PROTO) {
240 st->hand_state = TLS_ST_SR_NEXT_PROTO;
241 return 1;
242 }
243 } else {
244 #endif
245 if (mt == SSL3_MT_FINISHED) {
246 st->hand_state = TLS_ST_SR_FINISHED;
247 return 1;
248 }
249 #ifndef OPENSSL_NO_NEXTPROTONEG
250 }
251 #endif
252 break;
253
254 #ifndef OPENSSL_NO_NEXTPROTONEG
255 case TLS_ST_SR_NEXT_PROTO:
256 if (mt == SSL3_MT_FINISHED) {
257 st->hand_state = TLS_ST_SR_FINISHED;
258 return 1;
259 }
260 break;
261 #endif
262
263 case TLS_ST_SW_FINISHED:
264 if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
265 st->hand_state = TLS_ST_SR_CHANGE;
266 return 1;
267 }
268 break;
269 }
270
271 err:
272 /* No valid transition found */
273 SSLfatal(s, SSL3_AD_UNEXPECTED_MESSAGE,
274 SSL_F_OSSL_STATEM_SERVER_READ_TRANSITION,
275 SSL_R_UNEXPECTED_MESSAGE);
276 return 0;
277 }
278
279 /*
280 * Should we send a ServerKeyExchange message?
281 *
282 * Valid return values are:
283 * 1: Yes
284 * 0: No
285 */
286 static int send_server_key_exchange(SSL *s)
287 {
288 unsigned long alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
289
290 /*
291 * only send a ServerKeyExchange if DH or fortezza but we have a
292 * sign only certificate PSK: may send PSK identity hints For
293 * ECC ciphersuites, we send a serverKeyExchange message only if
294 * the cipher suite is either ECDH-anon or ECDHE. In other cases,
295 * the server certificate contains the server's public key for
296 * key exchange.
297 */
298 if (alg_k & (SSL_kDHE | SSL_kECDHE)
299 /*
300 * PSK: send ServerKeyExchange if PSK identity hint if
301 * provided
302 */
303 #ifndef OPENSSL_NO_PSK
304 /* Only send SKE if we have identity hint for plain PSK */
305 || ((alg_k & (SSL_kPSK | SSL_kRSAPSK))
306 && s->cert->psk_identity_hint)
307 /* For other PSK always send SKE */
308 || (alg_k & (SSL_PSK & (SSL_kDHEPSK | SSL_kECDHEPSK)))
309 #endif
310 #ifndef OPENSSL_NO_SRP
311 /* SRP: send ServerKeyExchange */
312 || (alg_k & SSL_kSRP)
313 #endif
314 ) {
315 return 1;
316 }
317
318 return 0;
319 }
320
321 /*
322 * Should we send a CertificateRequest message?
323 *
324 * Valid return values are:
325 * 1: Yes
326 * 0: No
327 */
328 static int send_certificate_request(SSL *s)
329 {
330 if (
331 /* don't request cert unless asked for it: */
332 s->verify_mode & SSL_VERIFY_PEER
333 /*
334 * if SSL_VERIFY_CLIENT_ONCE is set, don't request cert
335 * during re-negotiation:
336 */
337 && (s->s3->tmp.finish_md_len == 0 ||
338 !(s->verify_mode & SSL_VERIFY_CLIENT_ONCE))
339 /*
340 * never request cert in anonymous ciphersuites (see
341 * section "Certificate request" in SSL 3 drafts and in
342 * RFC 2246):
343 */
344 && (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL)
345 /*
346 * ... except when the application insists on
347 * verification (against the specs, but statem_clnt.c accepts
348 * this for SSL 3)
349 */
350 || (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT))
351 /* don't request certificate for SRP auth */
352 && !(s->s3->tmp.new_cipher->algorithm_auth & SSL_aSRP)
353 /*
354 * With normal PSK Certificates and Certificate Requests
355 * are omitted
356 */
357 && !(s->s3->tmp.new_cipher->algorithm_auth & SSL_aPSK)) {
358 return 1;
359 }
360
361 return 0;
362 }
363
364 /*
365 * ossl_statem_server13_write_transition() works out what handshake state to
366 * move to next when a TLSv1.3 server is writing messages to be sent to the
367 * client.
368 */
369 static WRITE_TRAN ossl_statem_server13_write_transition(SSL *s)
370 {
371 OSSL_STATEM *st = &s->statem;
372
373 /*
374 * No case for TLS_ST_BEFORE, because at that stage we have not negotiated
375 * TLSv1.3 yet, so that is handled by ossl_statem_server_write_transition()
376 */
377
378 switch (st->hand_state) {
379 default:
380 /* Shouldn't happen */
381 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
382 SSL_F_OSSL_STATEM_SERVER13_WRITE_TRANSITION,
383 ERR_R_INTERNAL_ERROR);
384 return WRITE_TRAN_ERROR;
385
386 case TLS_ST_OK:
387 if (s->key_update != SSL_KEY_UPDATE_NONE) {
388 st->hand_state = TLS_ST_SW_KEY_UPDATE;
389 return WRITE_TRAN_CONTINUE;
390 }
391 /* Try to read from the client instead */
392 return WRITE_TRAN_FINISHED;
393
394 case TLS_ST_SR_CLNT_HELLO:
395 if (s->hello_retry_request)
396 st->hand_state = TLS_ST_SW_HELLO_RETRY_REQUEST;
397 else
398 st->hand_state = TLS_ST_SW_SRVR_HELLO;
399 return WRITE_TRAN_CONTINUE;
400
401 case TLS_ST_SW_HELLO_RETRY_REQUEST:
402 st->hand_state = TLS_ST_EARLY_DATA;
403 return WRITE_TRAN_CONTINUE;
404
405 case TLS_ST_SW_SRVR_HELLO:
406 st->hand_state = TLS_ST_SW_ENCRYPTED_EXTENSIONS;
407 return WRITE_TRAN_CONTINUE;
408
409 case TLS_ST_SW_ENCRYPTED_EXTENSIONS:
410 if (s->hit)
411 st->hand_state = TLS_ST_SW_FINISHED;
412 else if (send_certificate_request(s))
413 st->hand_state = TLS_ST_SW_CERT_REQ;
414 else
415 st->hand_state = TLS_ST_SW_CERT;
416
417 return WRITE_TRAN_CONTINUE;
418
419 case TLS_ST_SW_CERT_REQ:
420 st->hand_state = TLS_ST_SW_CERT;
421 return WRITE_TRAN_CONTINUE;
422
423 case TLS_ST_SW_CERT:
424 st->hand_state = TLS_ST_SW_CERT_VRFY;
425 return WRITE_TRAN_CONTINUE;
426
427 case TLS_ST_SW_CERT_VRFY:
428 st->hand_state = TLS_ST_SW_FINISHED;
429 return WRITE_TRAN_CONTINUE;
430
431 case TLS_ST_SW_FINISHED:
432 st->hand_state = TLS_ST_EARLY_DATA;
433 return WRITE_TRAN_CONTINUE;
434
435 case TLS_ST_EARLY_DATA:
436 return WRITE_TRAN_FINISHED;
437
438 case TLS_ST_SR_FINISHED:
439 /*
440 * Technically we have finished the handshake at this point, but we're
441 * going to remain "in_init" for now and write out the session ticket
442 * immediately.
443 * TODO(TLS1.3): Perhaps we need to be able to control this behaviour
444 * and give the application the opportunity to delay sending the
445 * session ticket?
446 */
447 st->hand_state = TLS_ST_SW_SESSION_TICKET;
448 return WRITE_TRAN_CONTINUE;
449
450 case TLS_ST_SR_KEY_UPDATE:
451 if (s->key_update != SSL_KEY_UPDATE_NONE) {
452 st->hand_state = TLS_ST_SW_KEY_UPDATE;
453 return WRITE_TRAN_CONTINUE;
454 }
455 /* Fall through */
456
457 case TLS_ST_SW_KEY_UPDATE:
458 case TLS_ST_SW_SESSION_TICKET:
459 st->hand_state = TLS_ST_OK;
460 return WRITE_TRAN_CONTINUE;
461 }
462 }
463
464 /*
465 * ossl_statem_server_write_transition() works out what handshake state to move
466 * to next when the server is writing messages to be sent to the client.
467 */
468 WRITE_TRAN ossl_statem_server_write_transition(SSL *s)
469 {
470 OSSL_STATEM *st = &s->statem;
471
472 /*
473 * Note that before the ClientHello we don't know what version we are going
474 * to negotiate yet, so we don't take this branch until later
475 */
476
477 if (SSL_IS_TLS13(s))
478 return ossl_statem_server13_write_transition(s);
479
480 switch (st->hand_state) {
481 default:
482 /* Shouldn't happen */
483 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
484 SSL_F_OSSL_STATEM_SERVER_WRITE_TRANSITION,
485 ERR_R_INTERNAL_ERROR);
486 return WRITE_TRAN_ERROR;
487
488 case TLS_ST_OK:
489 if (st->request_state == TLS_ST_SW_HELLO_REQ) {
490 /* We must be trying to renegotiate */
491 st->hand_state = TLS_ST_SW_HELLO_REQ;
492 st->request_state = TLS_ST_BEFORE;
493 return WRITE_TRAN_CONTINUE;
494 }
495 /* Must be an incoming ClientHello */
496 if (!tls_setup_handshake(s)) {
497 /* SSLfatal() already called */
498 return WRITE_TRAN_ERROR;
499 }
500 /* Fall through */
501
502 case TLS_ST_BEFORE:
503 /* Just go straight to trying to read from the client */
504 return WRITE_TRAN_FINISHED;
505
506 case TLS_ST_SW_HELLO_REQ:
507 st->hand_state = TLS_ST_OK;
508 return WRITE_TRAN_CONTINUE;
509
510 case TLS_ST_SR_CLNT_HELLO:
511 if (SSL_IS_DTLS(s) && !s->d1->cookie_verified
512 && (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))
513 st->hand_state = DTLS_ST_SW_HELLO_VERIFY_REQUEST;
514 else
515 st->hand_state = TLS_ST_SW_SRVR_HELLO;
516 return WRITE_TRAN_CONTINUE;
517
518 case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
519 return WRITE_TRAN_FINISHED;
520
521 case TLS_ST_SW_SRVR_HELLO:
522 if (s->hit) {
523 if (s->ext.ticket_expected)
524 st->hand_state = TLS_ST_SW_SESSION_TICKET;
525 else
526 st->hand_state = TLS_ST_SW_CHANGE;
527 } else {
528 /* Check if it is anon DH or anon ECDH, */
529 /* normal PSK or SRP */
530 if (!(s->s3->tmp.new_cipher->algorithm_auth &
531 (SSL_aNULL | SSL_aSRP | SSL_aPSK))) {
532 st->hand_state = TLS_ST_SW_CERT;
533 } else if (send_server_key_exchange(s)) {
534 st->hand_state = TLS_ST_SW_KEY_EXCH;
535 } else if (send_certificate_request(s)) {
536 st->hand_state = TLS_ST_SW_CERT_REQ;
537 } else {
538 st->hand_state = TLS_ST_SW_SRVR_DONE;
539 }
540 }
541 return WRITE_TRAN_CONTINUE;
542
543 case TLS_ST_SW_CERT:
544 if (s->ext.status_expected) {
545 st->hand_state = TLS_ST_SW_CERT_STATUS;
546 return WRITE_TRAN_CONTINUE;
547 }
548 /* Fall through */
549
550 case TLS_ST_SW_CERT_STATUS:
551 if (send_server_key_exchange(s)) {
552 st->hand_state = TLS_ST_SW_KEY_EXCH;
553 return WRITE_TRAN_CONTINUE;
554 }
555 /* Fall through */
556
557 case TLS_ST_SW_KEY_EXCH:
558 if (send_certificate_request(s)) {
559 st->hand_state = TLS_ST_SW_CERT_REQ;
560 return WRITE_TRAN_CONTINUE;
561 }
562 /* Fall through */
563
564 case TLS_ST_SW_CERT_REQ:
565 st->hand_state = TLS_ST_SW_SRVR_DONE;
566 return WRITE_TRAN_CONTINUE;
567
568 case TLS_ST_SW_SRVR_DONE:
569 return WRITE_TRAN_FINISHED;
570
571 case TLS_ST_SR_FINISHED:
572 if (s->hit) {
573 st->hand_state = TLS_ST_OK;
574 return WRITE_TRAN_CONTINUE;
575 } else if (s->ext.ticket_expected) {
576 st->hand_state = TLS_ST_SW_SESSION_TICKET;
577 } else {
578 st->hand_state = TLS_ST_SW_CHANGE;
579 }
580 return WRITE_TRAN_CONTINUE;
581
582 case TLS_ST_SW_SESSION_TICKET:
583 st->hand_state = TLS_ST_SW_CHANGE;
584 return WRITE_TRAN_CONTINUE;
585
586 case TLS_ST_SW_CHANGE:
587 st->hand_state = TLS_ST_SW_FINISHED;
588 return WRITE_TRAN_CONTINUE;
589
590 case TLS_ST_SW_FINISHED:
591 if (s->hit) {
592 return WRITE_TRAN_FINISHED;
593 }
594 st->hand_state = TLS_ST_OK;
595 return WRITE_TRAN_CONTINUE;
596 }
597 }
598
599 /*
600 * Perform any pre work that needs to be done prior to sending a message from
601 * the server to the client.
602 */
603 WORK_STATE ossl_statem_server_pre_work(SSL *s, WORK_STATE wst)
604 {
605 OSSL_STATEM *st = &s->statem;
606
607 switch (st->hand_state) {
608 default:
609 /* No pre work to be done */
610 break;
611
612 case TLS_ST_SW_HELLO_REQ:
613 s->shutdown = 0;
614 if (SSL_IS_DTLS(s))
615 dtls1_clear_sent_buffer(s);
616 break;
617
618 case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
619 s->shutdown = 0;
620 if (SSL_IS_DTLS(s)) {
621 dtls1_clear_sent_buffer(s);
622 /* We don't buffer this message so don't use the timer */
623 st->use_timer = 0;
624 }
625 break;
626
627 case TLS_ST_SW_SRVR_HELLO:
628 if (SSL_IS_DTLS(s)) {
629 /*
630 * Messages we write from now on should be buffered and
631 * retransmitted if necessary, so we need to use the timer now
632 */
633 st->use_timer = 1;
634 }
635 break;
636
637 case TLS_ST_SW_SRVR_DONE:
638 #ifndef OPENSSL_NO_SCTP
639 if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s))) {
640 /* Calls SSLfatal() as required */
641 return dtls_wait_for_dry(s);
642 }
643 #endif
644 return WORK_FINISHED_CONTINUE;
645
646 case TLS_ST_SW_SESSION_TICKET:
647 if (SSL_IS_TLS13(s)) {
648 /*
649 * Actually this is the end of the handshake, but we're going
650 * straight into writing the session ticket out. So we finish off
651 * the handshake, but keep the various buffers active.
652 *
653 * Calls SSLfatal as required.
654 */
655 return tls_finish_handshake(s, wst, 0);
656 } if (SSL_IS_DTLS(s)) {
657 /*
658 * We're into the last flight. We don't retransmit the last flight
659 * unless we need to, so we don't use the timer
660 */
661 st->use_timer = 0;
662 }
663 break;
664
665 case TLS_ST_SW_CHANGE:
666 s->session->cipher = s->s3->tmp.new_cipher;
667 if (!s->method->ssl3_enc->setup_key_block(s)) {
668 /* SSLfatal() already called */
669 return WORK_ERROR;
670 }
671 if (SSL_IS_DTLS(s)) {
672 /*
673 * We're into the last flight. We don't retransmit the last flight
674 * unless we need to, so we don't use the timer. This might have
675 * already been set to 0 if we sent a NewSessionTicket message,
676 * but we'll set it again here in case we didn't.
677 */
678 st->use_timer = 0;
679 }
680 return WORK_FINISHED_CONTINUE;
681
682 case TLS_ST_EARLY_DATA:
683 if (s->early_data_state != SSL_EARLY_DATA_ACCEPTING)
684 return WORK_FINISHED_CONTINUE;
685 /* Fall through */
686
687 case TLS_ST_OK:
688 /* Calls SSLfatal() as required */
689 return tls_finish_handshake(s, wst, 1);
690 }
691
692 return WORK_FINISHED_CONTINUE;
693 }
694
695 /*
696 * Perform any work that needs to be done after sending a message from the
697 * server to the client.
698 */
699 WORK_STATE ossl_statem_server_post_work(SSL *s, WORK_STATE wst)
700 {
701 OSSL_STATEM *st = &s->statem;
702
703 s->init_num = 0;
704
705 switch (st->hand_state) {
706 default:
707 /* No post work to be done */
708 break;
709
710 case TLS_ST_SW_HELLO_RETRY_REQUEST:
711 if (statem_flush(s) != 1)
712 return WORK_MORE_A;
713 break;
714
715 case TLS_ST_SW_HELLO_REQ:
716 if (statem_flush(s) != 1)
717 return WORK_MORE_A;
718 if (!ssl3_init_finished_mac(s)) {
719 /* SSLfatal() already called */
720 return WORK_ERROR;
721 }
722 break;
723
724 case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
725 if (statem_flush(s) != 1)
726 return WORK_MORE_A;
727 /* HelloVerifyRequest resets Finished MAC */
728 if (s->version != DTLS1_BAD_VER && !ssl3_init_finished_mac(s)) {
729 /* SSLfatal() already called */
730 return WORK_ERROR;
731 }
732 /*
733 * The next message should be another ClientHello which we need to
734 * treat like it was the first packet
735 */
736 s->first_packet = 1;
737 break;
738
739 case TLS_ST_SW_SRVR_HELLO:
740 #ifndef OPENSSL_NO_SCTP
741 if (SSL_IS_DTLS(s) && s->hit) {
742 unsigned char sctpauthkey[64];
743 char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
744
745 /*
746 * Add new shared key for SCTP-Auth, will be ignored if no
747 * SCTP used.
748 */
749 memcpy(labelbuffer, DTLS1_SCTP_AUTH_LABEL,
750 sizeof(DTLS1_SCTP_AUTH_LABEL));
751
752 if (SSL_export_keying_material(s, sctpauthkey,
753 sizeof(sctpauthkey), labelbuffer,
754 sizeof(labelbuffer), NULL, 0,
755 0) <= 0) {
756 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
757 SSL_F_OSSL_STATEM_SERVER_POST_WORK,
758 ERR_R_INTERNAL_ERROR);
759 return WORK_ERROR;
760 }
761
762 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
763 sizeof(sctpauthkey), sctpauthkey);
764 }
765 #endif
766 /*
767 * TODO(TLS1.3): This actually causes a problem. We don't yet know
768 * whether the next record we are going to receive is an unencrypted
769 * alert, or an encrypted handshake message. We're going to need
770 * something clever in the record layer for this.
771 */
772 if (SSL_IS_TLS13(s)) {
773 if (!s->method->ssl3_enc->setup_key_block(s)
774 || !s->method->ssl3_enc->change_cipher_state(s,
775 SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_SERVER_WRITE)) {
776 /* SSLfatal() already called */
777 return WORK_ERROR;
778 }
779
780 if (s->ext.early_data != SSL_EARLY_DATA_ACCEPTED
781 && !s->method->ssl3_enc->change_cipher_state(s,
782 SSL3_CC_HANDSHAKE |SSL3_CHANGE_CIPHER_SERVER_READ)) {
783 /* SSLfatal() already called */
784 return WORK_ERROR;
785 }
786 }
787 break;
788
789 case TLS_ST_SW_CHANGE:
790 #ifndef OPENSSL_NO_SCTP
791 if (SSL_IS_DTLS(s) && !s->hit) {
792 /*
793 * Change to new shared key of SCTP-Auth, will be ignored if
794 * no SCTP used.
795 */
796 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
797 0, NULL);
798 }
799 #endif
800 if (!s->method->ssl3_enc->change_cipher_state(s,
801 SSL3_CHANGE_CIPHER_SERVER_WRITE))
802 {
803 /* SSLfatal() already called */
804 return WORK_ERROR;
805 }
806
807 if (SSL_IS_DTLS(s))
808 dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
809 break;
810
811 case TLS_ST_SW_SRVR_DONE:
812 if (statem_flush(s) != 1)
813 return WORK_MORE_A;
814 break;
815
816 case TLS_ST_SW_FINISHED:
817 if (statem_flush(s) != 1)
818 return WORK_MORE_A;
819 #ifndef OPENSSL_NO_SCTP
820 if (SSL_IS_DTLS(s) && s->hit) {
821 /*
822 * Change to new shared key of SCTP-Auth, will be ignored if
823 * no SCTP used.
824 */
825 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
826 0, NULL);
827 }
828 #endif
829 if (SSL_IS_TLS13(s)) {
830 if (!s->method->ssl3_enc->generate_master_secret(s,
831 s->master_secret, s->handshake_secret, 0,
832 &s->session->master_key_length)
833 || !s->method->ssl3_enc->change_cipher_state(s,
834 SSL3_CC_APPLICATION | SSL3_CHANGE_CIPHER_SERVER_WRITE))
835 /* SSLfatal() already called */
836 return WORK_ERROR;
837 }
838 break;
839
840 case TLS_ST_SW_KEY_UPDATE:
841 if (statem_flush(s) != 1)
842 return WORK_MORE_A;
843 if (!tls13_update_key(s, 1)) {
844 /* SSLfatal() already called */
845 return WORK_ERROR;
846 }
847 break;
848
849 case TLS_ST_SW_SESSION_TICKET:
850 if (SSL_IS_TLS13(s) && statem_flush(s) != 1)
851 return WORK_MORE_A;
852 break;
853 }
854
855 return WORK_FINISHED_CONTINUE;
856 }
857
858 /*
859 * Get the message construction function and message type for sending from the
860 * server
861 *
862 * Valid return values are:
863 * 1: Success
864 * 0: Error
865 */
866 int ossl_statem_server_construct_message(SSL *s, WPACKET *pkt,
867 confunc_f *confunc, int *mt)
868 {
869 OSSL_STATEM *st = &s->statem;
870
871 switch (st->hand_state) {
872 default:
873 /* Shouldn't happen */
874 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
875 SSL_F_OSSL_STATEM_SERVER_CONSTRUCT_MESSAGE,
876 SSL_R_BAD_HANDSHAKE_STATE);
877 return 0;
878
879 case TLS_ST_SW_CHANGE:
880 if (SSL_IS_DTLS(s))
881 *confunc = dtls_construct_change_cipher_spec;
882 else
883 *confunc = tls_construct_change_cipher_spec;
884 *mt = SSL3_MT_CHANGE_CIPHER_SPEC;
885 break;
886
887 case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
888 *confunc = dtls_construct_hello_verify_request;
889 *mt = DTLS1_MT_HELLO_VERIFY_REQUEST;
890 break;
891
892 case TLS_ST_SW_HELLO_REQ:
893 /* No construction function needed */
894 *confunc = NULL;
895 *mt = SSL3_MT_HELLO_REQUEST;
896 break;
897
898 case TLS_ST_SW_SRVR_HELLO:
899 *confunc = tls_construct_server_hello;
900 *mt = SSL3_MT_SERVER_HELLO;
901 break;
902
903 case TLS_ST_SW_CERT:
904 *confunc = tls_construct_server_certificate;
905 *mt = SSL3_MT_CERTIFICATE;
906 break;
907
908 case TLS_ST_SW_CERT_VRFY:
909 *confunc = tls_construct_cert_verify;
910 *mt = SSL3_MT_CERTIFICATE_VERIFY;
911 break;
912
913
914 case TLS_ST_SW_KEY_EXCH:
915 *confunc = tls_construct_server_key_exchange;
916 *mt = SSL3_MT_SERVER_KEY_EXCHANGE;
917 break;
918
919 case TLS_ST_SW_CERT_REQ:
920 *confunc = tls_construct_certificate_request;
921 *mt = SSL3_MT_CERTIFICATE_REQUEST;
922 break;
923
924 case TLS_ST_SW_SRVR_DONE:
925 *confunc = tls_construct_server_done;
926 *mt = SSL3_MT_SERVER_DONE;
927 break;
928
929 case TLS_ST_SW_SESSION_TICKET:
930 *confunc = tls_construct_new_session_ticket;
931 *mt = SSL3_MT_NEWSESSION_TICKET;
932 break;
933
934 case TLS_ST_SW_CERT_STATUS:
935 *confunc = tls_construct_cert_status;
936 *mt = SSL3_MT_CERTIFICATE_STATUS;
937 break;
938
939 case TLS_ST_SW_FINISHED:
940 *confunc = tls_construct_finished;
941 *mt = SSL3_MT_FINISHED;
942 break;
943
944 case TLS_ST_EARLY_DATA:
945 *confunc = NULL;
946 *mt = SSL3_MT_DUMMY;
947 break;
948
949 case TLS_ST_SW_ENCRYPTED_EXTENSIONS:
950 *confunc = tls_construct_encrypted_extensions;
951 *mt = SSL3_MT_ENCRYPTED_EXTENSIONS;
952 break;
953
954 case TLS_ST_SW_HELLO_RETRY_REQUEST:
955 *confunc = tls_construct_hello_retry_request;
956 *mt = SSL3_MT_HELLO_RETRY_REQUEST;
957 break;
958
959 case TLS_ST_SW_KEY_UPDATE:
960 *confunc = tls_construct_key_update;
961 *mt = SSL3_MT_KEY_UPDATE;
962 break;
963 }
964
965 return 1;
966 }
967
968 /*
969 * Maximum size (excluding the Handshake header) of a ClientHello message,
970 * calculated as follows:
971 *
972 * 2 + # client_version
973 * 32 + # only valid length for random
974 * 1 + # length of session_id
975 * 32 + # maximum size for session_id
976 * 2 + # length of cipher suites
977 * 2^16-2 + # maximum length of cipher suites array
978 * 1 + # length of compression_methods
979 * 2^8-1 + # maximum length of compression methods
980 * 2 + # length of extensions
981 * 2^16-1 # maximum length of extensions
982 */
983 #define CLIENT_HELLO_MAX_LENGTH 131396
984
985 #define CLIENT_KEY_EXCH_MAX_LENGTH 2048
986 #define NEXT_PROTO_MAX_LENGTH 514
987
988 /*
989 * Returns the maximum allowed length for the current message that we are
990 * reading. Excludes the message header.
991 */
992 size_t ossl_statem_server_max_message_size(SSL *s)
993 {
994 OSSL_STATEM *st = &s->statem;
995
996 switch (st->hand_state) {
997 default:
998 /* Shouldn't happen */
999 return 0;
1000
1001 case TLS_ST_SR_CLNT_HELLO:
1002 return CLIENT_HELLO_MAX_LENGTH;
1003
1004 case TLS_ST_SR_END_OF_EARLY_DATA:
1005 return END_OF_EARLY_DATA_MAX_LENGTH;
1006
1007 case TLS_ST_SR_CERT:
1008 return s->max_cert_list;
1009
1010 case TLS_ST_SR_KEY_EXCH:
1011 return CLIENT_KEY_EXCH_MAX_LENGTH;
1012
1013 case TLS_ST_SR_CERT_VRFY:
1014 return SSL3_RT_MAX_PLAIN_LENGTH;
1015
1016 #ifndef OPENSSL_NO_NEXTPROTONEG
1017 case TLS_ST_SR_NEXT_PROTO:
1018 return NEXT_PROTO_MAX_LENGTH;
1019 #endif
1020
1021 case TLS_ST_SR_CHANGE:
1022 return CCS_MAX_LENGTH;
1023
1024 case TLS_ST_SR_FINISHED:
1025 return FINISHED_MAX_LENGTH;
1026
1027 case TLS_ST_SR_KEY_UPDATE:
1028 return KEY_UPDATE_MAX_LENGTH;
1029 }
1030 }
1031
1032 /*
1033 * Process a message that the server has received from the client.
1034 */
1035 MSG_PROCESS_RETURN ossl_statem_server_process_message(SSL *s, PACKET *pkt)
1036 {
1037 OSSL_STATEM *st = &s->statem;
1038
1039 switch (st->hand_state) {
1040 default:
1041 /* Shouldn't happen */
1042 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
1043 SSL_F_OSSL_STATEM_SERVER_PROCESS_MESSAGE,
1044 ERR_R_INTERNAL_ERROR);
1045 return MSG_PROCESS_ERROR;
1046
1047 case TLS_ST_SR_CLNT_HELLO:
1048 return tls_process_client_hello(s, pkt);
1049
1050 case TLS_ST_SR_END_OF_EARLY_DATA:
1051 return tls_process_end_of_early_data(s, pkt);
1052
1053 case TLS_ST_SR_CERT:
1054 return tls_process_client_certificate(s, pkt);
1055
1056 case TLS_ST_SR_KEY_EXCH:
1057 return tls_process_client_key_exchange(s, pkt);
1058
1059 case TLS_ST_SR_CERT_VRFY:
1060 return tls_process_cert_verify(s, pkt);
1061
1062 #ifndef OPENSSL_NO_NEXTPROTONEG
1063 case TLS_ST_SR_NEXT_PROTO:
1064 return tls_process_next_proto(s, pkt);
1065 #endif
1066
1067 case TLS_ST_SR_CHANGE:
1068 return tls_process_change_cipher_spec(s, pkt);
1069
1070 case TLS_ST_SR_FINISHED:
1071 return tls_process_finished(s, pkt);
1072
1073 case TLS_ST_SR_KEY_UPDATE:
1074 return tls_process_key_update(s, pkt);
1075
1076 }
1077 }
1078
1079 /*
1080 * Perform any further processing required following the receipt of a message
1081 * from the client
1082 */
1083 WORK_STATE ossl_statem_server_post_process_message(SSL *s, WORK_STATE wst)
1084 {
1085 OSSL_STATEM *st = &s->statem;
1086
1087 switch (st->hand_state) {
1088 default:
1089 /* Shouldn't happen */
1090 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
1091 SSL_F_OSSL_STATEM_SERVER_POST_PROCESS_MESSAGE,
1092 ERR_R_INTERNAL_ERROR);
1093 return WORK_ERROR;
1094
1095 case TLS_ST_SR_CLNT_HELLO:
1096 return tls_post_process_client_hello(s, wst);
1097
1098 case TLS_ST_SR_KEY_EXCH:
1099 return tls_post_process_client_key_exchange(s, wst);
1100 }
1101 return WORK_FINISHED_CONTINUE;
1102 }
1103
1104 #ifndef OPENSSL_NO_SRP
1105 /* Returns 1 on success, 0 for retryable error, -1 for fatal error */
1106 static int ssl_check_srp_ext_ClientHello(SSL *s)
1107 {
1108 int ret;
1109 int al = SSL_AD_UNRECOGNIZED_NAME;
1110
1111 if ((s->s3->tmp.new_cipher->algorithm_mkey & SSL_kSRP) &&
1112 (s->srp_ctx.TLS_ext_srp_username_callback != NULL)) {
1113 if (s->srp_ctx.login == NULL) {
1114 /*
1115 * RFC 5054 says SHOULD reject, we do so if There is no srp
1116 * login name
1117 */
1118 SSLfatal(s, SSL_AD_UNKNOWN_PSK_IDENTITY,
1119 SSL_F_SSL_CHECK_SRP_EXT_CLIENTHELLO,
1120 SSL_R_PSK_IDENTITY_NOT_FOUND);
1121 return -1;
1122 } else {
1123 ret = SSL_srp_server_param_with_username(s, &al);
1124 if (ret < 0)
1125 return 0;
1126 if (ret == SSL3_AL_FATAL) {
1127 SSLfatal(s, al, SSL_F_SSL_CHECK_SRP_EXT_CLIENTHELLO,
1128 al == SSL_AD_UNKNOWN_PSK_IDENTITY
1129 ? SSL_R_PSK_IDENTITY_NOT_FOUND
1130 : SSL_R_CLIENTHELLO_TLSEXT);
1131 return -1;
1132 }
1133 }
1134 }
1135 return 1;
1136 }
1137 #endif
1138
1139 int dtls_raw_hello_verify_request(WPACKET *pkt, unsigned char *cookie,
1140 size_t cookie_len)
1141 {
1142 /* Always use DTLS 1.0 version: see RFC 6347 */
1143 if (!WPACKET_put_bytes_u16(pkt, DTLS1_VERSION)
1144 || !WPACKET_sub_memcpy_u8(pkt, cookie, cookie_len))
1145 return 0;
1146
1147 return 1;
1148 }
1149
1150 int dtls_construct_hello_verify_request(SSL *s, WPACKET *pkt)
1151 {
1152 unsigned int cookie_leni;
1153 if (s->ctx->app_gen_cookie_cb == NULL ||
1154 s->ctx->app_gen_cookie_cb(s, s->d1->cookie,
1155 &cookie_leni) == 0 ||
1156 cookie_leni > 255) {
1157 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_DTLS_CONSTRUCT_HELLO_VERIFY_REQUEST,
1158 SSL_R_COOKIE_GEN_CALLBACK_FAILURE);
1159 return 0;
1160 }
1161 s->d1->cookie_len = cookie_leni;
1162
1163 if (!dtls_raw_hello_verify_request(pkt, s->d1->cookie,
1164 s->d1->cookie_len)) {
1165 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_DTLS_CONSTRUCT_HELLO_VERIFY_REQUEST,
1166 ERR_R_INTERNAL_ERROR);
1167 return 0;
1168 }
1169
1170 return 1;
1171 }
1172
1173 #ifndef OPENSSL_NO_EC
1174 /*-
1175 * ssl_check_for_safari attempts to fingerprint Safari using OS X
1176 * SecureTransport using the TLS extension block in |hello|.
1177 * Safari, since 10.6, sends exactly these extensions, in this order:
1178 * SNI,
1179 * elliptic_curves
1180 * ec_point_formats
1181 * signature_algorithms (for TLSv1.2 only)
1182 *
1183 * We wish to fingerprint Safari because they broke ECDHE-ECDSA support in 10.8,
1184 * but they advertise support. So enabling ECDHE-ECDSA ciphers breaks them.
1185 * Sadly we cannot differentiate 10.6, 10.7 and 10.8.4 (which work), from
1186 * 10.8..10.8.3 (which don't work).
1187 */
1188 static void ssl_check_for_safari(SSL *s, const CLIENTHELLO_MSG *hello)
1189 {
1190 static const unsigned char kSafariExtensionsBlock[] = {
1191 0x00, 0x0a, /* elliptic_curves extension */
1192 0x00, 0x08, /* 8 bytes */
1193 0x00, 0x06, /* 6 bytes of curve ids */
1194 0x00, 0x17, /* P-256 */
1195 0x00, 0x18, /* P-384 */
1196 0x00, 0x19, /* P-521 */
1197
1198 0x00, 0x0b, /* ec_point_formats */
1199 0x00, 0x02, /* 2 bytes */
1200 0x01, /* 1 point format */
1201 0x00, /* uncompressed */
1202 /* The following is only present in TLS 1.2 */
1203 0x00, 0x0d, /* signature_algorithms */
1204 0x00, 0x0c, /* 12 bytes */
1205 0x00, 0x0a, /* 10 bytes */
1206 0x05, 0x01, /* SHA-384/RSA */
1207 0x04, 0x01, /* SHA-256/RSA */
1208 0x02, 0x01, /* SHA-1/RSA */
1209 0x04, 0x03, /* SHA-256/ECDSA */
1210 0x02, 0x03, /* SHA-1/ECDSA */
1211 };
1212 /* Length of the common prefix (first two extensions). */
1213 static const size_t kSafariCommonExtensionsLength = 18;
1214 unsigned int type;
1215 PACKET sni, tmppkt;
1216 size_t ext_len;
1217
1218 tmppkt = hello->extensions;
1219
1220 if (!PACKET_forward(&tmppkt, 2)
1221 || !PACKET_get_net_2(&tmppkt, &type)
1222 || !PACKET_get_length_prefixed_2(&tmppkt, &sni)) {
1223 return;
1224 }
1225
1226 if (type != TLSEXT_TYPE_server_name)
1227 return;
1228
1229 ext_len = TLS1_get_client_version(s) >= TLS1_2_VERSION ?
1230 sizeof(kSafariExtensionsBlock) : kSafariCommonExtensionsLength;
1231
1232 s->s3->is_probably_safari = PACKET_equal(&tmppkt, kSafariExtensionsBlock,
1233 ext_len);
1234 }
1235 #endif /* !OPENSSL_NO_EC */
1236
1237 MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
1238 {
1239 /* |cookie| will only be initialized for DTLS. */
1240 PACKET session_id, compression, extensions, cookie;
1241 static const unsigned char null_compression = 0;
1242 CLIENTHELLO_MSG *clienthello;
1243
1244 clienthello = OPENSSL_zalloc(sizeof(*clienthello));
1245 if (clienthello == NULL) {
1246 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO,
1247 ERR_R_INTERNAL_ERROR);
1248 goto err;
1249 }
1250 /* Check if this is actually an unexpected renegotiation ClientHello */
1251 if (s->renegotiate == 0 && !SSL_IS_FIRST_HANDSHAKE(s)) {
1252 if ((s->options & SSL_OP_NO_RENEGOTIATION)) {
1253 ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1254 goto err;
1255 }
1256 s->renegotiate = 1;
1257 s->new_session = 1;
1258 }
1259
1260 /*
1261 * First, parse the raw ClientHello data into the CLIENTHELLO_MSG structure.
1262 */
1263 clienthello->isv2 = RECORD_LAYER_is_sslv2_record(&s->rlayer);
1264 PACKET_null_init(&cookie);
1265
1266 if (clienthello->isv2) {
1267 unsigned int mt;
1268
1269 if (!SSL_IS_FIRST_HANDSHAKE(s) || s->hello_retry_request) {
1270 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE,
1271 SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_UNEXPECTED_MESSAGE);
1272 goto err;
1273 }
1274
1275 /*-
1276 * An SSLv3/TLSv1 backwards-compatible CLIENT-HELLO in an SSLv2
1277 * header is sent directly on the wire, not wrapped as a TLS
1278 * record. Our record layer just processes the message length and passes
1279 * the rest right through. Its format is:
1280 * Byte Content
1281 * 0-1 msg_length - decoded by the record layer
1282 * 2 msg_type - s->init_msg points here
1283 * 3-4 version
1284 * 5-6 cipher_spec_length
1285 * 7-8 session_id_length
1286 * 9-10 challenge_length
1287 * ... ...
1288 */
1289
1290 if (!PACKET_get_1(pkt, &mt)
1291 || mt != SSL2_MT_CLIENT_HELLO) {
1292 /*
1293 * Should never happen. We should have tested this in the record
1294 * layer in order to have determined that this is a SSLv2 record
1295 * in the first place
1296 */
1297 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO,
1298 ERR_R_INTERNAL_ERROR);
1299 goto err;
1300 }
1301 }
1302
1303 if (!PACKET_get_net_2(pkt, &clienthello->legacy_version)) {
1304 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO,
1305 SSL_R_LENGTH_TOO_SHORT);
1306 goto err;
1307 }
1308
1309 /* Parse the message and load client random. */
1310 if (clienthello->isv2) {
1311 /*
1312 * Handle an SSLv2 backwards compatible ClientHello
1313 * Note, this is only for SSLv3+ using the backward compatible format.
1314 * Real SSLv2 is not supported, and is rejected below.
1315 */
1316 unsigned int ciphersuite_len, session_id_len, challenge_len;
1317 PACKET challenge;
1318
1319 if (!PACKET_get_net_2(pkt, &ciphersuite_len)
1320 || !PACKET_get_net_2(pkt, &session_id_len)
1321 || !PACKET_get_net_2(pkt, &challenge_len)) {
1322 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO,
1323 SSL_R_RECORD_LENGTH_MISMATCH);
1324 goto err;
1325 }
1326
1327 if (session_id_len > SSL_MAX_SSL_SESSION_ID_LENGTH) {
1328 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1329 SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
1330 goto err;
1331 }
1332
1333 if (!PACKET_get_sub_packet(pkt, &clienthello->ciphersuites,
1334 ciphersuite_len)
1335 || !PACKET_copy_bytes(pkt, clienthello->session_id, session_id_len)
1336 || !PACKET_get_sub_packet(pkt, &challenge, challenge_len)
1337 /* No extensions. */
1338 || PACKET_remaining(pkt) != 0) {
1339 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO,
1340 SSL_R_RECORD_LENGTH_MISMATCH);
1341 goto err;
1342 }
1343 clienthello->session_id_len = session_id_len;
1344
1345 /* Load the client random and compression list. We use SSL3_RANDOM_SIZE
1346 * here rather than sizeof(clienthello->random) because that is the limit
1347 * for SSLv3 and it is fixed. It won't change even if
1348 * sizeof(clienthello->random) does.
1349 */
1350 challenge_len = challenge_len > SSL3_RANDOM_SIZE
1351 ? SSL3_RANDOM_SIZE : challenge_len;
1352 memset(clienthello->random, 0, SSL3_RANDOM_SIZE);
1353 if (!PACKET_copy_bytes(&challenge,
1354 clienthello->random + SSL3_RANDOM_SIZE -
1355 challenge_len, challenge_len)
1356 /* Advertise only null compression. */
1357 || !PACKET_buf_init(&compression, &null_compression, 1)) {
1358 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO,
1359 ERR_R_INTERNAL_ERROR);
1360 goto err;
1361 }
1362
1363 PACKET_null_init(&clienthello->extensions);
1364 } else {
1365 /* Regular ClientHello. */
1366 if (!PACKET_copy_bytes(pkt, clienthello->random, SSL3_RANDOM_SIZE)
1367 || !PACKET_get_length_prefixed_1(pkt, &session_id)
1368 || !PACKET_copy_all(&session_id, clienthello->session_id,
1369 SSL_MAX_SSL_SESSION_ID_LENGTH,
1370 &clienthello->session_id_len)) {
1371 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO,
1372 SSL_R_LENGTH_MISMATCH);
1373 goto err;
1374 }
1375
1376 if (SSL_IS_DTLS(s)) {
1377 if (!PACKET_get_length_prefixed_1(pkt, &cookie)) {
1378 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO,
1379 SSL_R_LENGTH_MISMATCH);
1380 goto err;
1381 }
1382 if (!PACKET_copy_all(&cookie, clienthello->dtls_cookie,
1383 DTLS1_COOKIE_LENGTH,
1384 &clienthello->dtls_cookie_len)) {
1385 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
1386 SSL_F_TLS_PROCESS_CLIENT_HELLO, ERR_R_INTERNAL_ERROR);
1387 goto err;
1388 }
1389 /*
1390 * If we require cookies and this ClientHello doesn't contain one,
1391 * just return since we do not want to allocate any memory yet.
1392 * So check cookie length...
1393 */
1394 if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) {
1395 if (clienthello->dtls_cookie_len == 0)
1396 return MSG_PROCESS_FINISHED_READING;
1397 }
1398 }
1399
1400 if (!PACKET_get_length_prefixed_2(pkt, &clienthello->ciphersuites)) {
1401 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO,
1402 SSL_R_LENGTH_MISMATCH);
1403 goto err;
1404 }
1405
1406 if (!PACKET_get_length_prefixed_1(pkt, &compression)) {
1407 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO,
1408 SSL_R_LENGTH_MISMATCH);
1409 goto err;
1410 }
1411
1412 /* Could be empty. */
1413 if (PACKET_remaining(pkt) == 0) {
1414 PACKET_null_init(&clienthello->extensions);
1415 } else {
1416 if (!PACKET_get_length_prefixed_2(pkt, &clienthello->extensions)
1417 || PACKET_remaining(pkt) != 0) {
1418 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO,
1419 SSL_R_LENGTH_MISMATCH);
1420 goto err;
1421 }
1422 }
1423 }
1424
1425 if (!PACKET_copy_all(&compression, clienthello->compressions,
1426 MAX_COMPRESSIONS_SIZE,
1427 &clienthello->compressions_len)) {
1428 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_HELLO,
1429 ERR_R_INTERNAL_ERROR);
1430 goto err;
1431 }
1432
1433 /* Preserve the raw extensions PACKET for later use */
1434 extensions = clienthello->extensions;
1435 if (!tls_collect_extensions(s, &extensions, SSL_EXT_CLIENT_HELLO,
1436 &clienthello->pre_proc_exts,
1437 &clienthello->pre_proc_exts_len, 1)) {
1438 /* SSLfatal already been called */
1439 goto err;
1440 }
1441 s->clienthello = clienthello;
1442
1443 return MSG_PROCESS_CONTINUE_PROCESSING;
1444
1445 err:
1446 if (clienthello != NULL)
1447 OPENSSL_free(clienthello->pre_proc_exts);
1448 OPENSSL_free(clienthello);
1449
1450 return MSG_PROCESS_ERROR;
1451 }
1452
1453 static int tls_early_post_process_client_hello(SSL *s)
1454 {
1455 unsigned int j;
1456 int i, al = SSL_AD_INTERNAL_ERROR;
1457 int protverr;
1458 size_t loop;
1459 unsigned long id;
1460 #ifndef OPENSSL_NO_COMP
1461 SSL_COMP *comp = NULL;
1462 #endif
1463 const SSL_CIPHER *c;
1464 STACK_OF(SSL_CIPHER) *ciphers = NULL;
1465 STACK_OF(SSL_CIPHER) *scsvs = NULL;
1466 CLIENTHELLO_MSG *clienthello = s->clienthello;
1467 DOWNGRADE dgrd = DOWNGRADE_NONE;
1468
1469 /* Finished parsing the ClientHello, now we can start processing it */
1470 /* Give the ClientHello callback a crack at things */
1471 if (s->ctx->client_hello_cb != NULL) {
1472 /* A failure in the ClientHello callback terminates the connection. */
1473 switch (s->ctx->client_hello_cb(s, &al, s->ctx->client_hello_cb_arg)) {
1474 case SSL_CLIENT_HELLO_SUCCESS:
1475 break;
1476 case SSL_CLIENT_HELLO_RETRY:
1477 s->rwstate = SSL_CLIENT_HELLO_CB;
1478 return -1;
1479 case SSL_CLIENT_HELLO_ERROR:
1480 default:
1481 SSLfatal(s, al,
1482 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1483 SSL_R_CALLBACK_FAILED);
1484 goto err;
1485 }
1486 }
1487
1488 /* Set up the client_random */
1489 memcpy(s->s3->client_random, clienthello->random, SSL3_RANDOM_SIZE);
1490
1491 /* Choose the version */
1492
1493 if (clienthello->isv2) {
1494 if (clienthello->legacy_version == SSL2_VERSION
1495 || (clienthello->legacy_version & 0xff00)
1496 != (SSL3_VERSION_MAJOR << 8)) {
1497 /*
1498 * This is real SSLv2 or something completely unknown. We don't
1499 * support it.
1500 */
1501 SSLfatal(s, SSL_AD_PROTOCOL_VERSION,
1502 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1503 SSL_R_UNKNOWN_PROTOCOL);
1504 goto err;
1505 }
1506 /* SSLv3/TLS */
1507 s->client_version = clienthello->legacy_version;
1508 }
1509 /*
1510 * Do SSL/TLS version negotiation if applicable. For DTLS we just check
1511 * versions are potentially compatible. Version negotiation comes later.
1512 */
1513 if (!SSL_IS_DTLS(s)) {
1514 protverr = ssl_choose_server_version(s, clienthello, &dgrd);
1515 } else if (s->method->version != DTLS_ANY_VERSION &&
1516 DTLS_VERSION_LT((int)clienthello->legacy_version, s->version)) {
1517 protverr = SSL_R_VERSION_TOO_LOW;
1518 } else {
1519 protverr = 0;
1520 }
1521
1522 if (protverr) {
1523 if (SSL_IS_FIRST_HANDSHAKE(s)) {
1524 /* like ssl3_get_record, send alert using remote version number */
1525 s->version = s->client_version = clienthello->legacy_version;
1526 }
1527 SSLfatal(s, SSL_AD_PROTOCOL_VERSION,
1528 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, protverr);
1529 goto err;
1530 }
1531
1532 /* TLSv1.3 specifies that a ClientHello must end on a record boundary */
1533 if (SSL_IS_TLS13(s) && RECORD_LAYER_processed_read_pending(&s->rlayer)) {
1534 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE,
1535 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1536 SSL_R_NOT_ON_RECORD_BOUNDARY);
1537 goto err;
1538 }
1539
1540 if (SSL_IS_DTLS(s)) {
1541 /* Empty cookie was already handled above by returning early. */
1542 if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) {
1543 if (s->ctx->app_verify_cookie_cb != NULL) {
1544 if (s->ctx->app_verify_cookie_cb(s, clienthello->dtls_cookie,
1545 clienthello->dtls_cookie_len) == 0) {
1546 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
1547 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1548 SSL_R_COOKIE_MISMATCH);
1549 goto err;
1550 /* else cookie verification succeeded */
1551 }
1552 /* default verification */
1553 } else if (s->d1->cookie_len != clienthello->dtls_cookie_len
1554 || memcmp(clienthello->dtls_cookie, s->d1->cookie,
1555 s->d1->cookie_len) != 0) {
1556 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
1557 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1558 SSL_R_COOKIE_MISMATCH);
1559 goto err;
1560 }
1561 s->d1->cookie_verified = 1;
1562 }
1563 if (s->method->version == DTLS_ANY_VERSION) {
1564 protverr = ssl_choose_server_version(s, clienthello, &dgrd);
1565 if (protverr != 0) {
1566 s->version = s->client_version;
1567 SSLfatal(s, SSL_AD_PROTOCOL_VERSION,
1568 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO, protverr);
1569 goto err;
1570 }
1571 }
1572 }
1573
1574 s->hit = 0;
1575
1576 if (!ssl_cache_cipherlist(s, &clienthello->ciphersuites,
1577 clienthello->isv2) ||
1578 !bytes_to_cipher_list(s, &clienthello->ciphersuites, &ciphers, &scsvs,
1579 clienthello->isv2, 1)) {
1580 /* SSLfatal() already called */
1581 goto err;
1582 }
1583
1584 s->s3->send_connection_binding = 0;
1585 /* Check what signalling cipher-suite values were received. */
1586 if (scsvs != NULL) {
1587 for(i = 0; i < sk_SSL_CIPHER_num(scsvs); i++) {
1588 c = sk_SSL_CIPHER_value(scsvs, i);
1589 if (SSL_CIPHER_get_id(c) == SSL3_CK_SCSV) {
1590 if (s->renegotiate) {
1591 /* SCSV is fatal if renegotiating */
1592 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
1593 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1594 SSL_R_SCSV_RECEIVED_WHEN_RENEGOTIATING);
1595 goto err;
1596 }
1597 s->s3->send_connection_binding = 1;
1598 } else if (SSL_CIPHER_get_id(c) == SSL3_CK_FALLBACK_SCSV &&
1599 !ssl_check_version_downgrade(s)) {
1600 /*
1601 * This SCSV indicates that the client previously tried
1602 * a higher version. We should fail if the current version
1603 * is an unexpected downgrade, as that indicates that the first
1604 * connection may have been tampered with in order to trigger
1605 * an insecure downgrade.
1606 */
1607 SSLfatal(s, SSL_AD_INAPPROPRIATE_FALLBACK,
1608 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1609 SSL_R_INAPPROPRIATE_FALLBACK);
1610 goto err;
1611 }
1612 }
1613 }
1614
1615 /* For TLSv1.3 we must select the ciphersuite *before* session resumption */
1616 if (SSL_IS_TLS13(s)) {
1617 const SSL_CIPHER *cipher =
1618 ssl3_choose_cipher(s, ciphers, SSL_get_ciphers(s));
1619
1620 if (cipher == NULL) {
1621 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
1622 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1623 SSL_R_NO_SHARED_CIPHER);
1624 goto err;
1625 }
1626 if (s->hello_retry_request
1627 && (s->s3->tmp.new_cipher == NULL
1628 || s->s3->tmp.new_cipher->id != cipher->id)) {
1629 /*
1630 * A previous HRR picked a different ciphersuite to the one we
1631 * just selected. Something must have changed.
1632 */
1633 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1634 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1635 SSL_R_BAD_CIPHER);
1636 goto err;
1637 }
1638 s->s3->tmp.new_cipher = cipher;
1639 }
1640
1641 /* We need to do this before getting the session */
1642 if (!tls_parse_extension(s, TLSEXT_IDX_extended_master_secret,
1643 SSL_EXT_CLIENT_HELLO,
1644 clienthello->pre_proc_exts, NULL, 0)) {
1645 /* SSLfatal() already called */
1646 goto err;
1647 }
1648
1649 /*
1650 * We don't allow resumption in a backwards compatible ClientHello.
1651 * TODO(openssl-team): in TLS1.1+, session_id MUST be empty.
1652 *
1653 * Versions before 0.9.7 always allow clients to resume sessions in
1654 * renegotiation. 0.9.7 and later allow this by default, but optionally
1655 * ignore resumption requests with flag
1656 * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION (it's a new flag rather
1657 * than a change to default behavior so that applications relying on
1658 * this for security won't even compile against older library versions).
1659 * 1.0.1 and later also have a function SSL_renegotiate_abbreviated() to
1660 * request renegotiation but not a new session (s->new_session remains
1661 * unset): for servers, this essentially just means that the
1662 * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION setting will be
1663 * ignored.
1664 */
1665 if (clienthello->isv2 ||
1666 (s->new_session &&
1667 (s->options & SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION))) {
1668 if (!ssl_get_new_session(s, 1)) {
1669 /* SSLfatal() already called */
1670 goto err;
1671 }
1672 } else {
1673 i = ssl_get_prev_session(s, clienthello);
1674 if (i == 1) {
1675 /* previous session */
1676 s->hit = 1;
1677 } else if (i == -1) {
1678 /* SSLfatal() already called */
1679 goto err;
1680 } else {
1681 /* i == 0 */
1682 if (!ssl_get_new_session(s, 1)) {
1683 /* SSLfatal() already called */
1684 goto err;
1685 }
1686 }
1687 }
1688
1689 /*
1690 * If it is a hit, check that the cipher is in the list. In TLSv1.3 we check
1691 * ciphersuite compatibility with the session as part of resumption.
1692 */
1693 if (!SSL_IS_TLS13(s) && s->hit) {
1694 j = 0;
1695 id = s->session->cipher->id;
1696
1697 #ifdef CIPHER_DEBUG
1698 fprintf(stderr, "client sent %d ciphers\n", sk_SSL_CIPHER_num(ciphers));
1699 #endif
1700 for (i = 0; i < sk_SSL_CIPHER_num(ciphers); i++) {
1701 c = sk_SSL_CIPHER_value(ciphers, i);
1702 #ifdef CIPHER_DEBUG
1703 fprintf(stderr, "client [%2d of %2d]:%s\n",
1704 i, sk_SSL_CIPHER_num(ciphers), SSL_CIPHER_get_name(c));
1705 #endif
1706 if (c->id == id) {
1707 j = 1;
1708 break;
1709 }
1710 }
1711 if (j == 0) {
1712 /*
1713 * we need to have the cipher in the cipher list if we are asked
1714 * to reuse it
1715 */
1716 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1717 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1718 SSL_R_REQUIRED_CIPHER_MISSING);
1719 goto err;
1720 }
1721 }
1722
1723 for (loop = 0; loop < clienthello->compressions_len; loop++) {
1724 if (clienthello->compressions[loop] == 0)
1725 break;
1726 }
1727
1728 if (loop >= clienthello->compressions_len) {
1729 /* no compress */
1730 SSLfatal(s, SSL_AD_DECODE_ERROR,
1731 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1732 SSL_R_NO_COMPRESSION_SPECIFIED);
1733 goto err;
1734 }
1735
1736 #ifndef OPENSSL_NO_EC
1737 if (s->options & SSL_OP_SAFARI_ECDHE_ECDSA_BUG)
1738 ssl_check_for_safari(s, clienthello);
1739 #endif /* !OPENSSL_NO_EC */
1740
1741 /* TLS extensions */
1742 if (!tls_parse_all_extensions(s, SSL_EXT_CLIENT_HELLO,
1743 clienthello->pre_proc_exts, NULL, 0, 1)) {
1744 /* SSLfatal() already called */
1745 goto err;
1746 }
1747
1748 /*
1749 * Check if we want to use external pre-shared secret for this handshake
1750 * for not reused session only. We need to generate server_random before
1751 * calling tls_session_secret_cb in order to allow SessionTicket
1752 * processing to use it in key derivation.
1753 */
1754 {
1755 unsigned char *pos;
1756 pos = s->s3->server_random;
1757 if (ssl_fill_hello_random(s, 1, pos, SSL3_RANDOM_SIZE, dgrd) <= 0) {
1758 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
1759 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1760 ERR_R_INTERNAL_ERROR);
1761 goto err;
1762 }
1763 }
1764
1765 if (!s->hit
1766 && s->version >= TLS1_VERSION
1767 && !SSL_IS_TLS13(s)
1768 && !SSL_IS_DTLS(s)
1769 && s->ext.session_secret_cb) {
1770 const SSL_CIPHER *pref_cipher = NULL;
1771 /*
1772 * s->session->master_key_length is a size_t, but this is an int for
1773 * backwards compat reasons
1774 */
1775 int master_key_length;
1776
1777 master_key_length = sizeof(s->session->master_key);
1778 if (s->ext.session_secret_cb(s, s->session->master_key,
1779 &master_key_length, ciphers,
1780 &pref_cipher,
1781 s->ext.session_secret_cb_arg)
1782 && master_key_length > 0) {
1783 s->session->master_key_length = master_key_length;
1784 s->hit = 1;
1785 s->session->ciphers = ciphers;
1786 s->session->verify_result = X509_V_OK;
1787
1788 ciphers = NULL;
1789
1790 /* check if some cipher was preferred by call back */
1791 if (pref_cipher == NULL)
1792 pref_cipher = ssl3_choose_cipher(s, s->session->ciphers,
1793 SSL_get_ciphers(s));
1794 if (pref_cipher == NULL) {
1795 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
1796 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1797 SSL_R_NO_SHARED_CIPHER);
1798 goto err;
1799 }
1800
1801 s->session->cipher = pref_cipher;
1802 sk_SSL_CIPHER_free(s->cipher_list);
1803 s->cipher_list = sk_SSL_CIPHER_dup(s->session->ciphers);
1804 sk_SSL_CIPHER_free(s->cipher_list_by_id);
1805 s->cipher_list_by_id = sk_SSL_CIPHER_dup(s->session->ciphers);
1806 }
1807 }
1808
1809 /*
1810 * Worst case, we will use the NULL compression, but if we have other
1811 * options, we will now look for them. We have complen-1 compression
1812 * algorithms from the client, starting at q.
1813 */
1814 s->s3->tmp.new_compression = NULL;
1815 if (SSL_IS_TLS13(s)) {
1816 /*
1817 * We already checked above that the NULL compression method appears in
1818 * the list. Now we check there aren't any others (which is illegal in
1819 * a TLSv1.3 ClientHello.
1820 */
1821 if (clienthello->compressions_len != 1) {
1822 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1823 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1824 SSL_R_INVALID_COMPRESSION_ALGORITHM);
1825 goto err;
1826 }
1827 }
1828 #ifndef OPENSSL_NO_COMP
1829 /* This only happens if we have a cache hit */
1830 else if (s->session->compress_meth != 0) {
1831 int m, comp_id = s->session->compress_meth;
1832 unsigned int k;
1833 /* Perform sanity checks on resumed compression algorithm */
1834 /* Can't disable compression */
1835 if (!ssl_allow_compression(s)) {
1836 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
1837 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1838 SSL_R_INCONSISTENT_COMPRESSION);
1839 goto err;
1840 }
1841 /* Look for resumed compression method */
1842 for (m = 0; m < sk_SSL_COMP_num(s->ctx->comp_methods); m++) {
1843 comp = sk_SSL_COMP_value(s->ctx->comp_methods, m);
1844 if (comp_id == comp->id) {
1845 s->s3->tmp.new_compression = comp;
1846 break;
1847 }
1848 }
1849 if (s->s3->tmp.new_compression == NULL) {
1850 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
1851 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1852 SSL_R_INVALID_COMPRESSION_ALGORITHM);
1853 goto err;
1854 }
1855 /* Look for resumed method in compression list */
1856 for (k = 0; k < clienthello->compressions_len; k++) {
1857 if (clienthello->compressions[k] == comp_id)
1858 break;
1859 }
1860 if (k >= clienthello->compressions_len) {
1861 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1862 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1863 SSL_R_REQUIRED_COMPRESSION_ALGORITHM_MISSING);
1864 goto err;
1865 }
1866 } else if (s->hit) {
1867 comp = NULL;
1868 } else if (ssl_allow_compression(s) && s->ctx->comp_methods) {
1869 /* See if we have a match */
1870 int m, nn, v, done = 0;
1871 unsigned int o;
1872
1873 nn = sk_SSL_COMP_num(s->ctx->comp_methods);
1874 for (m = 0; m < nn; m++) {
1875 comp = sk_SSL_COMP_value(s->ctx->comp_methods, m);
1876 v = comp->id;
1877 for (o = 0; o < clienthello->compressions_len; o++) {
1878 if (v == clienthello->compressions[o]) {
1879 done = 1;
1880 break;
1881 }
1882 }
1883 if (done)
1884 break;
1885 }
1886 if (done)
1887 s->s3->tmp.new_compression = comp;
1888 else
1889 comp = NULL;
1890 }
1891 #else
1892 /*
1893 * If compression is disabled we'd better not try to resume a session
1894 * using compression.
1895 */
1896 if (s->session->compress_meth != 0) {
1897 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
1898 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1899 SSL_R_INCONSISTENT_COMPRESSION);
1900 goto err;
1901 }
1902 #endif
1903
1904 /*
1905 * Given s->session->ciphers and SSL_get_ciphers, we must pick a cipher
1906 */
1907
1908 if (!s->hit || SSL_IS_TLS13(s)) {
1909 sk_SSL_CIPHER_free(s->session->ciphers);
1910 s->session->ciphers = ciphers;
1911 if (ciphers == NULL) {
1912 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
1913 SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO,
1914 ERR_R_INTERNAL_ERROR);
1915 goto err;
1916 }
1917 ciphers = NULL;
1918 }
1919
1920 if (!s->hit) {
1921 #ifdef OPENSSL_NO_COMP
1922 s->session->compress_meth = 0;
1923 #else
1924 s->session->compress_meth = (comp == NULL) ? 0 : comp->id;
1925 #endif
1926 if (!tls1_set_server_sigalgs(s)) {
1927 /* SSLfatal() already called */
1928 goto err;
1929 }
1930 }
1931
1932 sk_SSL_CIPHER_free(ciphers);
1933 sk_SSL_CIPHER_free(scsvs);
1934 OPENSSL_free(clienthello->pre_proc_exts);
1935 OPENSSL_free(s->clienthello);
1936 s->clienthello = NULL;
1937 return 1;
1938 err:
1939 sk_SSL_CIPHER_free(ciphers);
1940 sk_SSL_CIPHER_free(scsvs);
1941 OPENSSL_free(clienthello->pre_proc_exts);
1942 OPENSSL_free(s->clienthello);
1943 s->clienthello = NULL;
1944
1945 return 0;
1946 }
1947
1948 /*
1949 * Call the status request callback if needed. Upon success, returns 1.
1950 * Upon failure, returns 0.
1951 */
1952 static int tls_handle_status_request(SSL *s)
1953 {
1954 s->ext.status_expected = 0;
1955
1956 /*
1957 * If status request then ask callback what to do. Note: this must be
1958 * called after servername callbacks in case the certificate has changed,
1959 * and must be called after the cipher has been chosen because this may
1960 * influence which certificate is sent
1961 */
1962 if (s->ext.status_type != TLSEXT_STATUSTYPE_nothing && s->ctx != NULL
1963 && s->ctx->ext.status_cb != NULL) {
1964 int ret;
1965
1966 /* If no certificate can't return certificate status */
1967 if (s->s3->tmp.cert != NULL) {
1968 /*
1969 * Set current certificate to one we will use so SSL_get_certificate
1970 * et al can pick it up.
1971 */
1972 s->cert->key = s->s3->tmp.cert;
1973 ret = s->ctx->ext.status_cb(s, s->ctx->ext.status_arg);
1974 switch (ret) {
1975 /* We don't want to send a status request response */
1976 case SSL_TLSEXT_ERR_NOACK:
1977 s->ext.status_expected = 0;
1978 break;
1979 /* status request response should be sent */
1980 case SSL_TLSEXT_ERR_OK:
1981 if (s->ext.ocsp.resp)
1982 s->ext.status_expected = 1;
1983 break;
1984 /* something bad happened */
1985 case SSL_TLSEXT_ERR_ALERT_FATAL:
1986 default:
1987 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
1988 SSL_F_TLS_HANDLE_STATUS_REQUEST,
1989 SSL_R_CLIENTHELLO_TLSEXT);
1990 return 0;
1991 }
1992 }
1993 }
1994
1995 return 1;
1996 }
1997
1998 /*
1999 * Call the alpn_select callback if needed. Upon success, returns 1.
2000 * Upon failure, returns 0.
2001 */
2002 int tls_handle_alpn(SSL *s)
2003 {
2004 const unsigned char *selected = NULL;
2005 unsigned char selected_len = 0;
2006
2007 if (s->ctx->ext.alpn_select_cb != NULL && s->s3->alpn_proposed != NULL) {
2008 int r = s->ctx->ext.alpn_select_cb(s, &selected, &selected_len,
2009 s->s3->alpn_proposed,
2010 (unsigned int)s->s3->alpn_proposed_len,
2011 s->ctx->ext.alpn_select_cb_arg);
2012
2013 if (r == SSL_TLSEXT_ERR_OK) {
2014 OPENSSL_free(s->s3->alpn_selected);
2015 s->s3->alpn_selected = OPENSSL_memdup(selected, selected_len);
2016 if (s->s3->alpn_selected == NULL) {
2017 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_HANDLE_ALPN,
2018 ERR_R_INTERNAL_ERROR);
2019 return 0;
2020 }
2021 s->s3->alpn_selected_len = selected_len;
2022 #ifndef OPENSSL_NO_NEXTPROTONEG
2023 /* ALPN takes precedence over NPN. */
2024 s->s3->npn_seen = 0;
2025 #endif
2026
2027 /* Check ALPN is consistent with session */
2028 if (s->session->ext.alpn_selected == NULL
2029 || selected_len != s->session->ext.alpn_selected_len
2030 || memcmp(selected, s->session->ext.alpn_selected,
2031 selected_len) != 0) {
2032 /* Not consistent so can't be used for early_data */
2033 s->ext.early_data_ok = 0;
2034
2035 if (!s->hit) {
2036 /* If a new session update it with the new ALPN value */
2037 s->session->ext.alpn_selected = OPENSSL_memdup(selected,
2038 selected_len);
2039 if (s->session->ext.alpn_selected == NULL) {
2040 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2041 SSL_F_TLS_HANDLE_ALPN,
2042 ERR_R_INTERNAL_ERROR);
2043 return 0;
2044 }
2045 s->session->ext.alpn_selected_len = selected_len;
2046 }
2047 }
2048
2049 return 1;
2050 } else if (r != SSL_TLSEXT_ERR_NOACK) {
2051 SSLfatal(s, SSL_AD_NO_APPLICATION_PROTOCOL, SSL_F_TLS_HANDLE_ALPN,
2052 SSL_R_NO_APPLICATION_PROTOCOL);
2053 return 0;
2054 }
2055 /*
2056 * If r == SSL_TLSEXT_ERR_NOACK then behave as if no callback was
2057 * present.
2058 */
2059 }
2060
2061 /* Check ALPN is consistent with session */
2062 if (s->session->ext.alpn_selected != NULL) {
2063 /* Not consistent so can't be used for early_data */
2064 s->ext.early_data_ok = 0;
2065 }
2066
2067 return 1;
2068 }
2069
2070 WORK_STATE tls_post_process_client_hello(SSL *s, WORK_STATE wst)
2071 {
2072 const SSL_CIPHER *cipher;
2073
2074 if (wst == WORK_MORE_A) {
2075 int rv = tls_early_post_process_client_hello(s);
2076 if (rv == 0) {
2077 /* SSLfatal() was already called */
2078 goto err;
2079 }
2080 if (rv < 0)
2081 return WORK_MORE_A;
2082 wst = WORK_MORE_B;
2083 }
2084 if (wst == WORK_MORE_B) {
2085 if (!s->hit || SSL_IS_TLS13(s)) {
2086 /* Let cert callback update server certificates if required */
2087 if (!s->hit && s->cert->cert_cb != NULL) {
2088 int rv = s->cert->cert_cb(s, s->cert->cert_cb_arg);
2089 if (rv == 0) {
2090 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2091 SSL_F_TLS_POST_PROCESS_CLIENT_HELLO,
2092 SSL_R_CERT_CB_ERROR);
2093 goto err;
2094 }
2095 if (rv < 0) {
2096 s->rwstate = SSL_X509_LOOKUP;
2097 return WORK_MORE_B;
2098 }
2099 s->rwstate = SSL_NOTHING;
2100 }
2101
2102 /* In TLSv1.3 we selected the ciphersuite before resumption */
2103 if (!SSL_IS_TLS13(s)) {
2104 cipher =
2105 ssl3_choose_cipher(s, s->session->ciphers, SSL_get_ciphers(s));
2106
2107 if (cipher == NULL) {
2108 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
2109 SSL_F_TLS_POST_PROCESS_CLIENT_HELLO,
2110 SSL_R_NO_SHARED_CIPHER);
2111 goto err;
2112 }
2113 s->s3->tmp.new_cipher = cipher;
2114 }
2115 if (!s->hit) {
2116 if (!tls_choose_sigalg(s, 1)) {
2117 /* SSLfatal already called */
2118 goto err;
2119 }
2120 /* check whether we should disable session resumption */
2121 if (s->not_resumable_session_cb != NULL)
2122 s->session->not_resumable =
2123 s->not_resumable_session_cb(s,
2124 ((s->s3->tmp.new_cipher->algorithm_mkey
2125 & (SSL_kDHE | SSL_kECDHE)) != 0));
2126 if (s->session->not_resumable)
2127 /* do not send a session ticket */
2128 s->ext.ticket_expected = 0;
2129 }
2130 } else {
2131 /* Session-id reuse */
2132 s->s3->tmp.new_cipher = s->session->cipher;
2133 }
2134
2135 /*-
2136 * we now have the following setup.
2137 * client_random
2138 * cipher_list - our preferred list of ciphers
2139 * ciphers - the clients preferred list of ciphers
2140 * compression - basically ignored right now
2141 * ssl version is set - sslv3
2142 * s->session - The ssl session has been setup.
2143 * s->hit - session reuse flag
2144 * s->s3->tmp.new_cipher- the new cipher to use.
2145 */
2146
2147 /*
2148 * Call status_request callback if needed. Has to be done after the
2149 * certificate callbacks etc above.
2150 */
2151 if (!tls_handle_status_request(s)) {
2152 /* SSLfatal() already called */
2153 goto err;
2154 }
2155 /*
2156 * Call alpn_select callback if needed. Has to be done after SNI and
2157 * cipher negotiation (HTTP/2 restricts permitted ciphers). In TLSv1.3
2158 * we already did this because cipher negotiation happens earlier, and
2159 * we must handle ALPN before we decide whether to accept early_data.
2160 */
2161 if (!SSL_IS_TLS13(s) && !tls_handle_alpn(s)) {
2162 /* SSLfatal() already called */
2163 goto err;
2164 }
2165
2166 wst = WORK_MORE_C;
2167 }
2168 #ifndef OPENSSL_NO_SRP
2169 if (wst == WORK_MORE_C) {
2170 int ret;
2171 if ((ret = ssl_check_srp_ext_ClientHello(s)) == 0) {
2172 /*
2173 * callback indicates further work to be done
2174 */
2175 s->rwstate = SSL_X509_LOOKUP;
2176 return WORK_MORE_C;
2177 }
2178 if (ret < 0) {
2179 /* SSLfatal() already called */
2180 goto err;
2181 }
2182 }
2183 #endif
2184
2185 return WORK_FINISHED_STOP;
2186 err:
2187 return WORK_ERROR;
2188 }
2189
2190 int tls_construct_server_hello(SSL *s, WPACKET *pkt)
2191 {
2192 int compm;
2193 size_t sl, len;
2194 int version;
2195
2196 /* TODO(TLS1.3): Remove the DRAFT conditional before release */
2197 version = SSL_IS_TLS13(s) ? TLS1_3_VERSION_DRAFT : s->version;
2198 if (!WPACKET_put_bytes_u16(pkt, version)
2199 /*
2200 * Random stuff. Filling of the server_random takes place in
2201 * tls_process_client_hello()
2202 */
2203 || !WPACKET_memcpy(pkt, s->s3->server_random, SSL3_RANDOM_SIZE)) {
2204 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_HELLO,
2205 ERR_R_INTERNAL_ERROR);
2206 return 0;
2207 }
2208
2209 /*-
2210 * There are several cases for the session ID to send
2211 * back in the server hello:
2212 * - For session reuse from the session cache,
2213 * we send back the old session ID.
2214 * - If stateless session reuse (using a session ticket)
2215 * is successful, we send back the client's "session ID"
2216 * (which doesn't actually identify the session).
2217 * - If it is a new session, we send back the new
2218 * session ID.
2219 * - However, if we want the new session to be single-use,
2220 * we send back a 0-length session ID.
2221 * s->hit is non-zero in either case of session reuse,
2222 * so the following won't overwrite an ID that we're supposed
2223 * to send back.
2224 */
2225 if (s->session->not_resumable ||
2226 (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER)
2227 && !s->hit))
2228 s->session->session_id_length = 0;
2229
2230 sl = s->session->session_id_length;
2231 if (sl > sizeof(s->session->session_id)) {
2232 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_SERVER_HELLO,
2233 ERR_R_INTERNAL_ERROR);
2234 return 0;
2235 }
2236
2237 /* set up the compression method */
2238 #ifdef OPENSSL_NO_COMP
2239 compm = 0;
2240 #else
2241 if (s->s3->tmp.new_compression == NULL)
2242 compm = 0;
2243 else
2244 compm = s->s3->tmp.new_compression->id;
2245 #endif
2246
2247 if ((!SSL_IS_TLS13(s)
2248 && !WPACKET_sub_memcpy_u8(pkt, s->session->session_id, sl))
2249 || !s->method->put_cipher_by_char(s->s3->tmp.new_cipher, pkt, &len)
2250 || (!SSL_IS_TLS13(s)
2251 && !WPACKET_put_bytes_u8(pkt, compm))
2252 || !tls_construct_extensions(s, pkt,
2253 SSL_IS_TLS13(s)
2254 ? SSL_EXT_TLS1_3_SERVER_HELLO
2255 : SSL_EXT_TLS1_2_SERVER_HELLO,
2256 NULL, 0)) {
2257 /* SSLfatal() already called */
2258 return 0;
2259 }
2260
2261 if (!(s->verify_mode & SSL_VERIFY_PEER)
2262 && !ssl3_digest_cached_records(s, 0)) {
2263 /* SSLfatal() already called */;
2264 return 0;
2265 }
2266
2267 return 1;
2268 }
2269
2270 int tls_construct_server_done(SSL *s, WPACKET *pkt)
2271 {
2272 if (!s->s3->tmp.cert_request) {
2273 if (!ssl3_digest_cached_records(s, 0)) {
2274 /* SSLfatal() already called */
2275 return 0;
2276 }
2277 }
2278 return 1;
2279 }
2280
2281 int tls_construct_server_key_exchange(SSL *s, WPACKET *pkt)
2282 {
2283 #ifndef OPENSSL_NO_DH
2284 EVP_PKEY *pkdh = NULL;
2285 #endif
2286 #ifndef OPENSSL_NO_EC
2287 unsigned char *encodedPoint = NULL;
2288 size_t encodedlen = 0;
2289 int curve_id = 0;
2290 #endif
2291 const SIGALG_LOOKUP *lu = s->s3->tmp.sigalg;
2292 int i;
2293 unsigned long type;
2294 const BIGNUM *r[4];
2295 EVP_MD_CTX *md_ctx = EVP_MD_CTX_new();
2296 EVP_PKEY_CTX *pctx = NULL;
2297 size_t paramlen, paramoffset;
2298
2299 if (!WPACKET_get_total_written(pkt, &paramoffset)) {
2300 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2301 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
2302 goto err;
2303 }
2304
2305 if (md_ctx == NULL) {
2306 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2307 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_MALLOC_FAILURE);
2308 goto err;
2309 }
2310
2311 type = s->s3->tmp.new_cipher->algorithm_mkey;
2312
2313 r[0] = r[1] = r[2] = r[3] = NULL;
2314 #ifndef OPENSSL_NO_PSK
2315 /* Plain PSK or RSAPSK nothing to do */
2316 if (type & (SSL_kPSK | SSL_kRSAPSK)) {
2317 } else
2318 #endif /* !OPENSSL_NO_PSK */
2319 #ifndef OPENSSL_NO_DH
2320 if (type & (SSL_kDHE | SSL_kDHEPSK)) {
2321 CERT *cert = s->cert;
2322
2323 EVP_PKEY *pkdhp = NULL;
2324 DH *dh;
2325
2326 if (s->cert->dh_tmp_auto) {
2327 DH *dhp = ssl_get_auto_dh(s);
2328 pkdh = EVP_PKEY_new();
2329 if (pkdh == NULL || dhp == NULL) {
2330 DH_free(dhp);
2331 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2332 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2333 ERR_R_INTERNAL_ERROR);
2334 goto err;
2335 }
2336 EVP_PKEY_assign_DH(pkdh, dhp);
2337 pkdhp = pkdh;
2338 } else {
2339 pkdhp = cert->dh_tmp;
2340 }
2341 if ((pkdhp == NULL) && (s->cert->dh_tmp_cb != NULL)) {
2342 DH *dhp = s->cert->dh_tmp_cb(s, 0, 1024);
2343 pkdh = ssl_dh_to_pkey(dhp);
2344 if (pkdh == NULL) {
2345 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2346 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2347 ERR_R_INTERNAL_ERROR);
2348 goto err;
2349 }
2350 pkdhp = pkdh;
2351 }
2352 if (pkdhp == NULL) {
2353 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2354 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2355 SSL_R_MISSING_TMP_DH_KEY);
2356 goto err;
2357 }
2358 if (!ssl_security(s, SSL_SECOP_TMP_DH,
2359 EVP_PKEY_security_bits(pkdhp), 0, pkdhp)) {
2360 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
2361 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2362 SSL_R_DH_KEY_TOO_SMALL);
2363 goto err;
2364 }
2365 if (s->s3->tmp.pkey != NULL) {
2366 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2367 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2368 ERR_R_INTERNAL_ERROR);
2369 goto err;
2370 }
2371
2372 s->s3->tmp.pkey = ssl_generate_pkey(pkdhp);
2373 if (s->s3->tmp.pkey == NULL) {
2374 /* SSLfatal() already called */
2375 goto err;
2376 }
2377
2378 dh = EVP_PKEY_get0_DH(s->s3->tmp.pkey);
2379
2380 EVP_PKEY_free(pkdh);
2381 pkdh = NULL;
2382
2383 DH_get0_pqg(dh, &r[0], NULL, &r[1]);
2384 DH_get0_key(dh, &r[2], NULL);
2385 } else
2386 #endif
2387 #ifndef OPENSSL_NO_EC
2388 if (type & (SSL_kECDHE | SSL_kECDHEPSK)) {
2389
2390 if (s->s3->tmp.pkey != NULL) {
2391 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2392 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2393 ERR_R_INTERNAL_ERROR);
2394 goto err;
2395 }
2396
2397 /* Get NID of appropriate shared curve */
2398 curve_id = tls1_shared_group(s, -2);
2399 if (curve_id == 0) {
2400 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
2401 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2402 SSL_R_UNSUPPORTED_ELLIPTIC_CURVE);
2403 goto err;
2404 }
2405 s->s3->tmp.pkey = ssl_generate_pkey_group(s, curve_id);
2406 /* Generate a new key for this curve */
2407 if (s->s3->tmp.pkey == NULL) {
2408 /* SSLfatal() already called */
2409 goto err;
2410 }
2411
2412 /* Encode the public key. */
2413 encodedlen = EVP_PKEY_get1_tls_encodedpoint(s->s3->tmp.pkey,
2414 &encodedPoint);
2415 if (encodedlen == 0) {
2416 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2417 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_EC_LIB);
2418 goto err;
2419 }
2420
2421 /*
2422 * We'll generate the serverKeyExchange message explicitly so we
2423 * can set these to NULLs
2424 */
2425 r[0] = NULL;
2426 r[1] = NULL;
2427 r[2] = NULL;
2428 r[3] = NULL;
2429 } else
2430 #endif /* !OPENSSL_NO_EC */
2431 #ifndef OPENSSL_NO_SRP
2432 if (type & SSL_kSRP) {
2433 if ((s->srp_ctx.N == NULL) ||
2434 (s->srp_ctx.g == NULL) ||
2435 (s->srp_ctx.s == NULL) || (s->srp_ctx.B == NULL)) {
2436 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2437 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2438 SSL_R_MISSING_SRP_PARAM);
2439 goto err;
2440 }
2441 r[0] = s->srp_ctx.N;
2442 r[1] = s->srp_ctx.g;
2443 r[2] = s->srp_ctx.s;
2444 r[3] = s->srp_ctx.B;
2445 } else
2446 #endif
2447 {
2448 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2449 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2450 SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE);
2451 goto err;
2452 }
2453
2454 if (((s->s3->tmp.new_cipher->algorithm_auth & (SSL_aNULL | SSL_aSRP)) != 0)
2455 || ((s->s3->tmp.new_cipher->algorithm_mkey & SSL_PSK)) != 0) {
2456 lu = NULL;
2457 } else if (lu == NULL) {
2458 SSLfatal(s, SSL_AD_DECODE_ERROR,
2459 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
2460 goto err;
2461 }
2462
2463 #ifndef OPENSSL_NO_PSK
2464 if (type & SSL_PSK) {
2465 size_t len = (s->cert->psk_identity_hint == NULL)
2466 ? 0 : strlen(s->cert->psk_identity_hint);
2467
2468 /*
2469 * It should not happen that len > PSK_MAX_IDENTITY_LEN - we already
2470 * checked this when we set the identity hint - but just in case
2471 */
2472 if (len > PSK_MAX_IDENTITY_LEN
2473 || !WPACKET_sub_memcpy_u16(pkt, s->cert->psk_identity_hint,
2474 len)) {
2475 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2476 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2477 ERR_R_INTERNAL_ERROR);
2478 goto err;
2479 }
2480 }
2481 #endif
2482
2483 for (i = 0; i < 4 && r[i] != NULL; i++) {
2484 unsigned char *binval;
2485 int res;
2486
2487 #ifndef OPENSSL_NO_SRP
2488 if ((i == 2) && (type & SSL_kSRP)) {
2489 res = WPACKET_start_sub_packet_u8(pkt);
2490 } else
2491 #endif
2492 res = WPACKET_start_sub_packet_u16(pkt);
2493
2494 if (!res) {
2495 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2496 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2497 ERR_R_INTERNAL_ERROR);
2498 goto err;
2499 }
2500
2501 #ifndef OPENSSL_NO_DH
2502 /*-
2503 * for interoperability with some versions of the Microsoft TLS
2504 * stack, we need to zero pad the DHE pub key to the same length
2505 * as the prime
2506 */
2507 if ((i == 2) && (type & (SSL_kDHE | SSL_kDHEPSK))) {
2508 size_t len = BN_num_bytes(r[0]) - BN_num_bytes(r[2]);
2509
2510 if (len > 0) {
2511 if (!WPACKET_allocate_bytes(pkt, len, &binval)) {
2512 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2513 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2514 ERR_R_INTERNAL_ERROR);
2515 goto err;
2516 }
2517 memset(binval, 0, len);
2518 }
2519 }
2520 #endif
2521 if (!WPACKET_allocate_bytes(pkt, BN_num_bytes(r[i]), &binval)
2522 || !WPACKET_close(pkt)) {
2523 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2524 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2525 ERR_R_INTERNAL_ERROR);
2526 goto err;
2527 }
2528
2529 BN_bn2bin(r[i], binval);
2530 }
2531
2532 #ifndef OPENSSL_NO_EC
2533 if (type & (SSL_kECDHE | SSL_kECDHEPSK)) {
2534 /*
2535 * We only support named (not generic) curves. In this situation, the
2536 * ServerKeyExchange message has: [1 byte CurveType], [2 byte CurveName]
2537 * [1 byte length of encoded point], followed by the actual encoded
2538 * point itself
2539 */
2540 if (!WPACKET_put_bytes_u8(pkt, NAMED_CURVE_TYPE)
2541 || !WPACKET_put_bytes_u8(pkt, 0)
2542 || !WPACKET_put_bytes_u8(pkt, curve_id)
2543 || !WPACKET_sub_memcpy_u8(pkt, encodedPoint, encodedlen)) {
2544 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2545 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2546 ERR_R_INTERNAL_ERROR);
2547 goto err;
2548 }
2549 OPENSSL_free(encodedPoint);
2550 encodedPoint = NULL;
2551 }
2552 #endif
2553
2554 /* not anonymous */
2555 if (lu != NULL) {
2556 EVP_PKEY *pkey = s->s3->tmp.cert->privatekey;
2557 const EVP_MD *md;
2558 unsigned char *sigbytes1, *sigbytes2, *tbs;
2559 size_t siglen, tbslen;
2560 int rv;
2561
2562 if (pkey == NULL || !tls1_lookup_md(lu, &md)) {
2563 /* Should never happen */
2564 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2565 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2566 ERR_R_INTERNAL_ERROR);
2567 goto err;
2568 }
2569 /*
2570 * n is the length of the params, they start at &(d[4]) and p
2571 * points to the space at the end.
2572 */
2573
2574 /* Get length of the parameters we have written above */
2575 if (!WPACKET_get_length(pkt, &paramlen)) {
2576 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2577 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2578 ERR_R_INTERNAL_ERROR);
2579 goto err;
2580 }
2581 /* send signature algorithm */
2582 if (SSL_USE_SIGALGS(s) && !WPACKET_put_bytes_u16(pkt, lu->sigalg)) {
2583 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2584 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2585 ERR_R_INTERNAL_ERROR);
2586 goto err;
2587 }
2588 /*
2589 * Create the signature. We don't know the actual length of the sig
2590 * until after we've created it, so we reserve enough bytes for it
2591 * up front, and then properly allocate them in the WPACKET
2592 * afterwards.
2593 */
2594 siglen = EVP_PKEY_size(pkey);
2595 if (!WPACKET_sub_reserve_bytes_u16(pkt, siglen, &sigbytes1)
2596 || EVP_DigestSignInit(md_ctx, &pctx, md, NULL, pkey) <= 0) {
2597 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2598 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2599 ERR_R_INTERNAL_ERROR);
2600 goto err;
2601 }
2602 if (lu->sig == EVP_PKEY_RSA_PSS) {
2603 if (EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) <= 0
2604 || EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, RSA_PSS_SALTLEN_DIGEST) <= 0) {
2605 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2606 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2607 ERR_R_EVP_LIB);
2608 goto err;
2609 }
2610 }
2611 tbslen = construct_key_exchange_tbs(s, &tbs,
2612 s->init_buf->data + paramoffset,
2613 paramlen);
2614 if (tbslen == 0) {
2615 /* SSLfatal() already called */
2616 goto err;
2617 }
2618 rv = EVP_DigestSign(md_ctx, sigbytes1, &siglen, tbs, tbslen);
2619 OPENSSL_free(tbs);
2620 if (rv <= 0 || !WPACKET_sub_allocate_bytes_u16(pkt, siglen, &sigbytes2)
2621 || sigbytes1 != sigbytes2) {
2622 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2623 SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2624 ERR_R_INTERNAL_ERROR);
2625 goto err;
2626 }
2627 }
2628
2629 EVP_MD_CTX_free(md_ctx);
2630 return 1;
2631 err:
2632 #ifndef OPENSSL_NO_DH
2633 EVP_PKEY_free(pkdh);
2634 #endif
2635 #ifndef OPENSSL_NO_EC
2636 OPENSSL_free(encodedPoint);
2637 #endif
2638 EVP_MD_CTX_free(md_ctx);
2639 return 0;
2640 }
2641
2642 int tls_construct_certificate_request(SSL *s, WPACKET *pkt)
2643 {
2644 if (SSL_IS_TLS13(s)) {
2645 /* TODO(TLS1.3) for now send empty request context */
2646 if (!WPACKET_put_bytes_u8(pkt, 0)) {
2647 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2648 SSL_F_TLS_CONSTRUCT_CERTIFICATE_REQUEST,
2649 ERR_R_INTERNAL_ERROR);
2650 return 0;
2651 }
2652
2653 if (!tls_construct_extensions(s, pkt,
2654 SSL_EXT_TLS1_3_CERTIFICATE_REQUEST, NULL,
2655 0)) {
2656 /* SSLfatal() already called */
2657 return 0;
2658 }
2659 goto done;
2660 }
2661
2662 /* get the list of acceptable cert types */
2663 if (!WPACKET_start_sub_packet_u8(pkt)
2664 || !ssl3_get_req_cert_type(s, pkt) || !WPACKET_close(pkt)) {
2665 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2666 SSL_F_TLS_CONSTRUCT_CERTIFICATE_REQUEST, ERR_R_INTERNAL_ERROR);
2667 return 0;
2668 }
2669
2670 if (SSL_USE_SIGALGS(s)) {
2671 const uint16_t *psigs;
2672 size_t nl = tls12_get_psigalgs(s, 1, &psigs);
2673
2674 if (!WPACKET_start_sub_packet_u16(pkt)
2675 || !WPACKET_set_flags(pkt, WPACKET_FLAGS_NON_ZERO_LENGTH)
2676 || !tls12_copy_sigalgs(s, pkt, psigs, nl)
2677 || !WPACKET_close(pkt)) {
2678 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2679 SSL_F_TLS_CONSTRUCT_CERTIFICATE_REQUEST,
2680 ERR_R_INTERNAL_ERROR);
2681 return 0;
2682 }
2683 }
2684
2685 if (!construct_ca_names(s, pkt)) {
2686 /* SSLfatal() already called */
2687 return 0;
2688 }
2689
2690 done:
2691 s->s3->tmp.cert_request = 1;
2692 return 1;
2693 }
2694
2695 static int tls_process_cke_psk_preamble(SSL *s, PACKET *pkt)
2696 {
2697 #ifndef OPENSSL_NO_PSK
2698 unsigned char psk[PSK_MAX_PSK_LEN];
2699 size_t psklen;
2700 PACKET psk_identity;
2701
2702 if (!PACKET_get_length_prefixed_2(pkt, &psk_identity)) {
2703 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE,
2704 SSL_R_LENGTH_MISMATCH);
2705 return 0;
2706 }
2707 if (PACKET_remaining(&psk_identity) > PSK_MAX_IDENTITY_LEN) {
2708 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE,
2709 SSL_R_DATA_LENGTH_TOO_LONG);
2710 return 0;
2711 }
2712 if (s->psk_server_callback == NULL) {
2713 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE,
2714 SSL_R_PSK_NO_SERVER_CB);
2715 return 0;
2716 }
2717
2718 if (!PACKET_strndup(&psk_identity, &s->session->psk_identity)) {
2719 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE,
2720 ERR_R_INTERNAL_ERROR);
2721 return 0;
2722 }
2723
2724 psklen = s->psk_server_callback(s, s->session->psk_identity,
2725 psk, sizeof(psk));
2726
2727 if (psklen > PSK_MAX_PSK_LEN) {
2728 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE,
2729 ERR_R_INTERNAL_ERROR);
2730 return 0;
2731 } else if (psklen == 0) {
2732 /*
2733 * PSK related to the given identity not found
2734 */
2735 SSLfatal(s, SSL_AD_UNKNOWN_PSK_IDENTITY,
2736 SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE,
2737 SSL_R_PSK_IDENTITY_NOT_FOUND);
2738 return 0;
2739 }
2740
2741 OPENSSL_free(s->s3->tmp.psk);
2742 s->s3->tmp.psk = OPENSSL_memdup(psk, psklen);
2743 OPENSSL_cleanse(psk, psklen);
2744
2745 if (s->s3->tmp.psk == NULL) {
2746 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
2747 SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE, ERR_R_MALLOC_FAILURE);
2748 return 0;
2749 }
2750
2751 s->s3->tmp.psklen = psklen;
2752
2753 return 1;
2754 #else
2755 /* Should never happen */
2756 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE,
2757 ERR_R_INTERNAL_ERROR);
2758 return 0;
2759 #endif
2760 }
2761
2762 static int tls_process_cke_rsa(SSL *s, PACKET *pkt)
2763 {
2764 #ifndef OPENSSL_NO_RSA
2765 unsigned char rand_premaster_secret[SSL_MAX_MASTER_KEY_LENGTH];
2766 int decrypt_len;
2767 unsigned char decrypt_good, version_good;
2768 size_t j, padding_len;
2769 PACKET enc_premaster;
2770 RSA *rsa = NULL;
2771 unsigned char *rsa_decrypt = NULL;
2772 int ret = 0;
2773
2774 rsa = EVP_PKEY_get0_RSA(s->cert->pkeys[SSL_PKEY_RSA].privatekey);
2775 if (rsa == NULL) {
2776 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_RSA,
2777 SSL_R_MISSING_RSA_CERTIFICATE);
2778 return 0;
2779 }
2780
2781 /* SSLv3 and pre-standard DTLS omit the length bytes. */
2782 if (s->version == SSL3_VERSION || s->version == DTLS1_BAD_VER) {
2783 enc_premaster = *pkt;
2784 } else {
2785 if (!PACKET_get_length_prefixed_2(pkt, &enc_premaster)
2786 || PACKET_remaining(pkt) != 0) {
2787 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_RSA,
2788 SSL_R_LENGTH_MISMATCH);
2789 return 0;
2790 }
2791 }
2792
2793 /*
2794 * We want to be sure that the plaintext buffer size makes it safe to
2795 * iterate over the entire size of a premaster secret
2796 * (SSL_MAX_MASTER_KEY_LENGTH). Reject overly short RSA keys because
2797 * their ciphertext cannot accommodate a premaster secret anyway.
2798 */
2799 if (RSA_size(rsa) < SSL_MAX_MASTER_KEY_LENGTH) {
2800 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_RSA,
2801 RSA_R_KEY_SIZE_TOO_SMALL);
2802 return 0;
2803 }
2804
2805 rsa_decrypt = OPENSSL_malloc(RSA_size(rsa));
2806 if (rsa_decrypt == NULL) {
2807 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_RSA,
2808 ERR_R_MALLOC_FAILURE);
2809 return 0;
2810 }
2811
2812 /*
2813 * We must not leak whether a decryption failure occurs because of
2814 * Bleichenbacher's attack on PKCS #1 v1.5 RSA padding (see RFC 2246,
2815 * section 7.4.7.1). The code follows that advice of the TLS RFC and
2816 * generates a random premaster secret for the case that the decrypt
2817 * fails. See https://tools.ietf.org/html/rfc5246#section-7.4.7.1
2818 */
2819
2820 if (ssl_randbytes(s, rand_premaster_secret,
2821 sizeof(rand_premaster_secret)) <= 0) {
2822 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_RSA,
2823 ERR_R_INTERNAL_ERROR);
2824 goto err;
2825 }
2826
2827 /*
2828 * Decrypt with no padding. PKCS#1 padding will be removed as part of
2829 * the timing-sensitive code below.
2830 */
2831 /* TODO(size_t): Convert this function */
2832 decrypt_len = (int)RSA_private_decrypt((int)PACKET_remaining(&enc_premaster),
2833 PACKET_data(&enc_premaster),
2834 rsa_decrypt, rsa, RSA_NO_PADDING);
2835 if (decrypt_len < 0) {
2836 SSLfatal(s, SSL_AD_DECRYPT_ERROR, SSL_F_TLS_PROCESS_CKE_RSA,
2837 ERR_R_INTERNAL_ERROR);
2838 goto err;
2839 }
2840
2841 /* Check the padding. See RFC 3447, section 7.2.2. */
2842
2843 /*
2844 * The smallest padded premaster is 11 bytes of overhead. Small keys
2845 * are publicly invalid, so this may return immediately. This ensures
2846 * PS is at least 8 bytes.
2847 */
2848 if (decrypt_len < 11 + SSL_MAX_MASTER_KEY_LENGTH) {
2849 SSLfatal(s, SSL_AD_DECRYPT_ERROR, SSL_F_TLS_PROCESS_CKE_RSA,
2850 SSL_R_DECRYPTION_FAILED);
2851 goto err;
2852 }
2853
2854 padding_len = decrypt_len - SSL_MAX_MASTER_KEY_LENGTH;
2855 decrypt_good = constant_time_eq_int_8(rsa_decrypt[0], 0) &
2856 constant_time_eq_int_8(rsa_decrypt[1], 2);
2857 for (j = 2; j < padding_len - 1; j++) {
2858 decrypt_good &= ~constant_time_is_zero_8(rsa_decrypt[j]);
2859 }
2860 decrypt_good &= constant_time_is_zero_8(rsa_decrypt[padding_len - 1]);
2861
2862 /*
2863 * If the version in the decrypted pre-master secret is correct then
2864 * version_good will be 0xff, otherwise it'll be zero. The
2865 * Klima-Pokorny-Rosa extension of Bleichenbacher's attack
2866 * (http://eprint.iacr.org/2003/052/) exploits the version number
2867 * check as a "bad version oracle". Thus version checks are done in
2868 * constant time and are treated like any other decryption error.
2869 */
2870 version_good =
2871 constant_time_eq_8(rsa_decrypt[padding_len],
2872 (unsigned)(s->client_version >> 8));
2873 version_good &=
2874 constant_time_eq_8(rsa_decrypt[padding_len + 1],
2875 (unsigned)(s->client_version & 0xff));
2876
2877 /*
2878 * The premaster secret must contain the same version number as the
2879 * ClientHello to detect version rollback attacks (strangely, the
2880 * protocol does not offer such protection for DH ciphersuites).
2881 * However, buggy clients exist that send the negotiated protocol
2882 * version instead if the server does not support the requested
2883 * protocol version. If SSL_OP_TLS_ROLLBACK_BUG is set, tolerate such
2884 * clients.
2885 */
2886 if (s->options & SSL_OP_TLS_ROLLBACK_BUG) {
2887 unsigned char workaround_good;
2888 workaround_good = constant_time_eq_8(rsa_decrypt[padding_len],
2889 (unsigned)(s->version >> 8));
2890 workaround_good &=
2891 constant_time_eq_8(rsa_decrypt[padding_len + 1],
2892 (unsigned)(s->version & 0xff));
2893 version_good |= workaround_good;
2894 }
2895
2896 /*
2897 * Both decryption and version must be good for decrypt_good to
2898 * remain non-zero (0xff).
2899 */
2900 decrypt_good &= version_good;
2901
2902 /*
2903 * Now copy rand_premaster_secret over from p using
2904 * decrypt_good_mask. If decryption failed, then p does not
2905 * contain valid plaintext, however, a check above guarantees
2906 * it is still sufficiently large to read from.
2907 */
2908 for (j = 0; j < sizeof(rand_premaster_secret); j++) {
2909 rsa_decrypt[padding_len + j] =
2910 constant_time_select_8(decrypt_good,
2911 rsa_decrypt[padding_len + j],
2912 rand_premaster_secret[j]);
2913 }
2914
2915 if (!ssl_generate_master_secret(s, rsa_decrypt + padding_len,
2916 sizeof(rand_premaster_secret), 0)) {
2917 /* SSLfatal() already called */
2918 goto err;
2919 }
2920
2921 ret = 1;
2922 err:
2923 OPENSSL_free(rsa_decrypt);
2924 return ret;
2925 #else
2926 /* Should never happen */
2927 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_RSA,
2928 ERR_R_INTERNAL_ERROR);
2929 return 0;
2930 #endif
2931 }
2932
2933 static int tls_process_cke_dhe(SSL *s, PACKET *pkt)
2934 {
2935 #ifndef OPENSSL_NO_DH
2936 EVP_PKEY *skey = NULL;
2937 DH *cdh;
2938 unsigned int i;
2939 BIGNUM *pub_key;
2940 const unsigned char *data;
2941 EVP_PKEY *ckey = NULL;
2942 int ret = 0;
2943
2944 if (!PACKET_get_net_2(pkt, &i) || PACKET_remaining(pkt) != i) {
2945 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_DHE,
2946 SSL_R_DH_PUBLIC_VALUE_LENGTH_IS_WRONG);
2947 goto err;
2948 }
2949 skey = s->s3->tmp.pkey;
2950 if (skey == NULL) {
2951 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_DHE,
2952 SSL_R_MISSING_TMP_DH_KEY);
2953 goto err;
2954 }
2955
2956 if (PACKET_remaining(pkt) == 0L) {
2957 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_DHE,
2958 SSL_R_MISSING_TMP_DH_KEY);
2959 goto err;
2960 }
2961 if (!PACKET_get_bytes(pkt, &data, i)) {
2962 /* We already checked we have enough data */
2963 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_DHE,
2964 ERR_R_INTERNAL_ERROR);
2965 goto err;
2966 }
2967 ckey = EVP_PKEY_new();
2968 if (ckey == NULL || EVP_PKEY_copy_parameters(ckey, skey) == 0) {
2969 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_DHE,
2970 SSL_R_BN_LIB);
2971 goto err;
2972 }
2973 cdh = EVP_PKEY_get0_DH(ckey);
2974 pub_key = BN_bin2bn(data, i, NULL);
2975
2976 if (pub_key == NULL || !DH_set0_key(cdh, pub_key, NULL)) {
2977 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_DHE,
2978 ERR_R_INTERNAL_ERROR);
2979 if (pub_key != NULL)
2980 BN_free(pub_key);
2981 goto err;
2982 }
2983
2984 if (ssl_derive(s, skey, ckey, 1) == 0) {
2985 /* SSLfatal() already called */
2986 goto err;
2987 }
2988
2989 ret = 1;
2990 EVP_PKEY_free(s->s3->tmp.pkey);
2991 s->s3->tmp.pkey = NULL;
2992 err:
2993 EVP_PKEY_free(ckey);
2994 return ret;
2995 #else
2996 /* Should never happen */
2997 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_DHE,
2998 ERR_R_INTERNAL_ERROR);
2999 return 0;
3000 #endif
3001 }
3002
3003 static int tls_process_cke_ecdhe(SSL *s, PACKET *pkt)
3004 {
3005 #ifndef OPENSSL_NO_EC
3006 EVP_PKEY *skey = s->s3->tmp.pkey;
3007 EVP_PKEY *ckey = NULL;
3008 int ret = 0;
3009
3010 if (PACKET_remaining(pkt) == 0L) {
3011 /* We don't support ECDH client auth */
3012 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_TLS_PROCESS_CKE_ECDHE,
3013 SSL_R_MISSING_TMP_ECDH_KEY);
3014 goto err;
3015 } else {
3016 unsigned int i;
3017 const unsigned char *data;
3018
3019 /*
3020 * Get client's public key from encoded point in the
3021 * ClientKeyExchange message.
3022 */
3023
3024 /* Get encoded point length */
3025 if (!PACKET_get_1(pkt, &i) || !PACKET_get_bytes(pkt, &data, i)
3026 || PACKET_remaining(pkt) != 0) {
3027 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_ECDHE,
3028 SSL_R_LENGTH_MISMATCH);
3029 goto err;
3030 }
3031 ckey = EVP_PKEY_new();
3032 if (ckey == NULL || EVP_PKEY_copy_parameters(ckey, skey) <= 0) {
3033 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_ECDHE,
3034 ERR_R_EVP_LIB);
3035 goto err;
3036 }
3037 if (EVP_PKEY_set1_tls_encodedpoint(ckey, data, i) == 0) {
3038 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_ECDHE,
3039 ERR_R_EC_LIB);
3040 goto err;
3041 }
3042 }
3043
3044 if (ssl_derive(s, skey, ckey, 1) == 0) {
3045 /* SSLfatal() already called */
3046 goto err;
3047 }
3048
3049 ret = 1;
3050 EVP_PKEY_free(s->s3->tmp.pkey);
3051 s->s3->tmp.pkey = NULL;
3052 err:
3053 EVP_PKEY_free(ckey);
3054
3055 return ret;
3056 #else
3057 /* Should never happen */
3058 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_ECDHE,
3059 ERR_R_INTERNAL_ERROR);
3060 return 0;
3061 #endif
3062 }
3063
3064 static int tls_process_cke_srp(SSL *s, PACKET *pkt)
3065 {
3066 #ifndef OPENSSL_NO_SRP
3067 unsigned int i;
3068 const unsigned char *data;
3069
3070 if (!PACKET_get_net_2(pkt, &i)
3071 || !PACKET_get_bytes(pkt, &data, i)) {
3072 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_SRP,
3073 SSL_R_BAD_SRP_A_LENGTH);
3074 return 0;
3075 }
3076 if ((s->srp_ctx.A = BN_bin2bn(data, i, NULL)) == NULL) {
3077 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_SRP,
3078 ERR_R_BN_LIB);
3079 return 0;
3080 }
3081 if (BN_ucmp(s->srp_ctx.A, s->srp_ctx.N) >= 0 || BN_is_zero(s->srp_ctx.A)) {
3082 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PROCESS_CKE_SRP,
3083 SSL_R_BAD_SRP_PARAMETERS);
3084 return 0;
3085 }
3086 OPENSSL_free(s->session->srp_username);
3087 s->session->srp_username = OPENSSL_strdup(s->srp_ctx.login);
3088 if (s->session->srp_username == NULL) {
3089 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_SRP,
3090 ERR_R_MALLOC_FAILURE);
3091 return 0;
3092 }
3093
3094 if (!srp_generate_server_master_secret(s)) {
3095 /* SSLfatal() already called */
3096 return 0;
3097 }
3098
3099 return 1;
3100 #else
3101 /* Should never happen */
3102 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_SRP,
3103 ERR_R_INTERNAL_ERROR);
3104 return 0;
3105 #endif
3106 }
3107
3108 static int tls_process_cke_gost(SSL *s, PACKET *pkt)
3109 {
3110 #ifndef OPENSSL_NO_GOST
3111 EVP_PKEY_CTX *pkey_ctx;
3112 EVP_PKEY *client_pub_pkey = NULL, *pk = NULL;
3113 unsigned char premaster_secret[32];
3114 const unsigned char *start;
3115 size_t outlen = 32, inlen;
3116 unsigned long alg_a;
3117 int Ttag, Tclass;
3118 long Tlen;
3119 size_t sess_key_len;
3120 const unsigned char *data;
3121 int ret = 0;
3122
3123 /* Get our certificate private key */
3124 alg_a = s->s3->tmp.new_cipher->algorithm_auth;
3125 if (alg_a & SSL_aGOST12) {
3126 /*
3127 * New GOST ciphersuites have SSL_aGOST01 bit too
3128 */
3129 pk = s->cert->pkeys[SSL_PKEY_GOST12_512].privatekey;
3130 if (pk == NULL) {
3131 pk = s->cert->pkeys[SSL_PKEY_GOST12_256].privatekey;
3132 }
3133 if (pk == NULL) {
3134 pk = s->cert->pkeys[SSL_PKEY_GOST01].privatekey;
3135 }
3136 } else if (alg_a & SSL_aGOST01) {
3137 pk = s->cert->pkeys[SSL_PKEY_GOST01].privatekey;
3138 }
3139
3140 pkey_ctx = EVP_PKEY_CTX_new(pk, NULL);
3141 if (pkey_ctx == NULL) {
3142 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_GOST,
3143 ERR_R_MALLOC_FAILURE);
3144 return 0;
3145 }
3146 if (EVP_PKEY_decrypt_init(pkey_ctx) <= 0) {
3147 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_GOST,
3148 ERR_R_INTERNAL_ERROR);
3149 return 0;
3150 }
3151 /*
3152 * If client certificate is present and is of the same type, maybe
3153 * use it for key exchange. Don't mind errors from
3154 * EVP_PKEY_derive_set_peer, because it is completely valid to use a
3155 * client certificate for authorization only.
3156 */
3157 client_pub_pkey = X509_get0_pubkey(s->session->peer);
3158 if (client_pub_pkey) {
3159 if (EVP_PKEY_derive_set_peer(pkey_ctx, client_pub_pkey) <= 0)
3160 ERR_clear_error();
3161 }
3162 /* Decrypt session key */
3163 sess_key_len = PACKET_remaining(pkt);
3164 if (!PACKET_get_bytes(pkt, &data, sess_key_len)) {
3165 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_GOST,
3166 ERR_R_INTERNAL_ERROR);
3167 goto err;
3168 }
3169 /* TODO(size_t): Convert this function */
3170 if (ASN1_get_object((const unsigned char **)&data, &Tlen, &Ttag,
3171 &Tclass, (long)sess_key_len) != V_ASN1_CONSTRUCTED
3172 || Ttag != V_ASN1_SEQUENCE || Tclass != V_ASN1_UNIVERSAL) {
3173 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_GOST,
3174 SSL_R_DECRYPTION_FAILED);
3175 goto err;
3176 }
3177 start = data;
3178 inlen = Tlen;
3179 if (EVP_PKEY_decrypt(pkey_ctx, premaster_secret, &outlen, start,
3180 inlen) <= 0) {
3181 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CKE_GOST,
3182 SSL_R_DECRYPTION_FAILED);
3183 goto err;
3184 }
3185 /* Generate master secret */
3186 if (!ssl_generate_master_secret(s, premaster_secret,
3187 sizeof(premaster_secret), 0)) {
3188 /* SSLfatal() already called */
3189 goto err;
3190 }
3191 /* Check if pubkey from client certificate was used */
3192 if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, -1, EVP_PKEY_CTRL_PEER_KEY, 2,
3193 NULL) > 0)
3194 s->statem.no_cert_verify = 1;
3195
3196 ret = 1;
3197 err:
3198 EVP_PKEY_CTX_free(pkey_ctx);
3199 return ret;
3200 #else
3201 /* Should never happen */
3202 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CKE_GOST,
3203 ERR_R_INTERNAL_ERROR);
3204 return 0;
3205 #endif
3206 }
3207
3208 MSG_PROCESS_RETURN tls_process_client_key_exchange(SSL *s, PACKET *pkt)
3209 {
3210 unsigned long alg_k;
3211
3212 alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
3213
3214 /* For PSK parse and retrieve identity, obtain PSK key */
3215 if ((alg_k & SSL_PSK) && !tls_process_cke_psk_preamble(s, pkt)) {
3216 /* SSLfatal() already called */
3217 goto err;
3218 }
3219
3220 if (alg_k & SSL_kPSK) {
3221 /* Identity extracted earlier: should be nothing left */
3222 if (PACKET_remaining(pkt) != 0) {
3223 SSLfatal(s, SSL_AD_DECODE_ERROR,
3224 SSL_F_TLS_PROCESS_CLIENT_KEY_EXCHANGE,
3225 SSL_R_LENGTH_MISMATCH);
3226 goto err;
3227 }
3228 /* PSK handled by ssl_generate_master_secret */
3229 if (!ssl_generate_master_secret(s, NULL, 0, 0)) {
3230 /* SSLfatal() already called */
3231 goto err;
3232 }
3233 } else if (alg_k & (SSL_kRSA | SSL_kRSAPSK)) {
3234 if (!tls_process_cke_rsa(s, pkt)) {
3235 /* SSLfatal() already called */
3236 goto err;
3237 }
3238 } else if (alg_k & (SSL_kDHE | SSL_kDHEPSK)) {
3239 if (!tls_process_cke_dhe(s, pkt)) {
3240 /* SSLfatal() already called */
3241 goto err;
3242 }
3243 } else if (alg_k & (SSL_kECDHE | SSL_kECDHEPSK)) {
3244 if (!tls_process_cke_ecdhe(s, pkt)) {
3245 /* SSLfatal() already called */
3246 goto err;
3247 }
3248 } else if (alg_k & SSL_kSRP) {
3249 if (!tls_process_cke_srp(s, pkt)) {
3250 /* SSLfatal() already called */
3251 goto err;
3252 }
3253 } else if (alg_k & SSL_kGOST) {
3254 if (!tls_process_cke_gost(s, pkt)) {
3255 /* SSLfatal() already called */
3256 goto err;
3257 }
3258 } else {
3259 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3260 SSL_F_TLS_PROCESS_CLIENT_KEY_EXCHANGE,
3261 SSL_R_UNKNOWN_CIPHER_TYPE);
3262 goto err;
3263 }
3264
3265 return MSG_PROCESS_CONTINUE_PROCESSING;
3266 err:
3267 #ifndef OPENSSL_NO_PSK
3268 OPENSSL_clear_free(s->s3->tmp.psk, s->s3->tmp.psklen);
3269 s->s3->tmp.psk = NULL;
3270 #endif
3271 return MSG_PROCESS_ERROR;
3272 }
3273
3274 WORK_STATE tls_post_process_client_key_exchange(SSL *s, WORK_STATE wst)
3275 {
3276 #ifndef OPENSSL_NO_SCTP
3277 if (wst == WORK_MORE_A) {
3278 if (SSL_IS_DTLS(s)) {
3279 unsigned char sctpauthkey[64];
3280 char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
3281 /*
3282 * Add new shared key for SCTP-Auth, will be ignored if no SCTP
3283 * used.
3284 */
3285 memcpy(labelbuffer, DTLS1_SCTP_AUTH_LABEL,
3286 sizeof(DTLS1_SCTP_AUTH_LABEL));
3287
3288 if (SSL_export_keying_material(s, sctpauthkey,
3289 sizeof(sctpauthkey), labelbuffer,
3290 sizeof(labelbuffer), NULL, 0,
3291 0) <= 0) {
3292 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3293 SSL_F_TLS_POST_PROCESS_CLIENT_KEY_EXCHANGE,
3294 ERR_R_INTERNAL_ERROR);
3295 return WORK_ERROR;
3296 }
3297
3298 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
3299 sizeof(sctpauthkey), sctpauthkey);
3300 }
3301 }
3302 #endif
3303
3304 if (s->statem.no_cert_verify || !s->session->peer) {
3305 /*
3306 * No certificate verify or no peer certificate so we no longer need
3307 * the handshake_buffer
3308 */
3309 if (!ssl3_digest_cached_records(s, 0)) {
3310 /* SSLfatal() already called */
3311 return WORK_ERROR;
3312 }
3313 return WORK_FINISHED_CONTINUE;
3314 } else {
3315 if (!s->s3->handshake_buffer) {
3316 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3317 SSL_F_TLS_POST_PROCESS_CLIENT_KEY_EXCHANGE,
3318 ERR_R_INTERNAL_ERROR);
3319 return WORK_ERROR;
3320 }
3321 /*
3322 * For sigalgs freeze the handshake buffer. If we support
3323 * extms we've done this already so this is a no-op
3324 */
3325 if (!ssl3_digest_cached_records(s, 1)) {
3326 /* SSLfatal() already called */
3327 return WORK_ERROR;
3328 }
3329 }
3330
3331 return WORK_FINISHED_CONTINUE;
3332 }
3333
3334 MSG_PROCESS_RETURN tls_process_client_certificate(SSL *s, PACKET *pkt)
3335 {
3336 int i;
3337 MSG_PROCESS_RETURN ret = MSG_PROCESS_ERROR;
3338 X509 *x = NULL;
3339 unsigned long l, llen;
3340 const unsigned char *certstart, *certbytes;
3341 STACK_OF(X509) *sk = NULL;
3342 PACKET spkt, context;
3343 size_t chainidx;
3344
3345 if ((sk = sk_X509_new_null()) == NULL) {
3346 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
3347 ERR_R_MALLOC_FAILURE);
3348 goto err;
3349 }
3350
3351 /* TODO(TLS1.3): For now we ignore the context. We need to verify this */
3352 if ((SSL_IS_TLS13(s) && !PACKET_get_length_prefixed_1(pkt, &context))
3353 || !PACKET_get_net_3(pkt, &llen)
3354 || !PACKET_get_sub_packet(pkt, &spkt, llen)
3355 || PACKET_remaining(pkt) != 0) {
3356 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
3357 SSL_R_LENGTH_MISMATCH);
3358 goto err;
3359 }
3360
3361 for (chainidx = 0; PACKET_remaining(&spkt) > 0; chainidx++) {
3362 if (!PACKET_get_net_3(&spkt, &l)
3363 || !PACKET_get_bytes(&spkt, &certbytes, l)) {
3364 SSLfatal(s, SSL_AD_DECODE_ERROR,
3365 SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
3366 SSL_R_CERT_LENGTH_MISMATCH);
3367 goto err;
3368 }
3369
3370 certstart = certbytes;
3371 x = d2i_X509(NULL, (const unsigned char **)&certbytes, l);
3372 if (x == NULL) {
3373 SSLfatal(s, SSL_AD_DECODE_ERROR,
3374 SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, ERR_R_ASN1_LIB);
3375 goto err;
3376 }
3377 if (certbytes != (certstart + l)) {
3378 SSLfatal(s, SSL_AD_DECODE_ERROR,
3379 SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
3380 SSL_R_CERT_LENGTH_MISMATCH);
3381 goto err;
3382 }
3383
3384 if (SSL_IS_TLS13(s)) {
3385 RAW_EXTENSION *rawexts = NULL;
3386 PACKET extensions;
3387
3388 if (!PACKET_get_length_prefixed_2(&spkt, &extensions)) {
3389 SSLfatal(s, SSL_AD_DECODE_ERROR,
3390 SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
3391 SSL_R_BAD_LENGTH);
3392 goto err;
3393 }
3394 if (!tls_collect_extensions(s, &extensions,
3395 SSL_EXT_TLS1_3_CERTIFICATE, &rawexts,
3396 NULL, chainidx == 0)
3397 || !tls_parse_all_extensions(s, SSL_EXT_TLS1_3_CERTIFICATE,
3398 rawexts, x, chainidx,
3399 PACKET_remaining(&spkt) == 0)) {
3400 OPENSSL_free(rawexts);
3401 goto err;
3402 }
3403 OPENSSL_free(rawexts);
3404 }
3405
3406 if (!sk_X509_push(sk, x)) {
3407 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3408 SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
3409 ERR_R_MALLOC_FAILURE);
3410 goto err;
3411 }
3412 x = NULL;
3413 }
3414
3415 if (sk_X509_num(sk) <= 0) {
3416 /* TLS does not mind 0 certs returned */
3417 if (s->version == SSL3_VERSION) {
3418 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
3419 SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
3420 SSL_R_NO_CERTIFICATES_RETURNED);
3421 goto err;
3422 }
3423 /* Fail for TLS only if we required a certificate */
3424 else if ((s->verify_mode & SSL_VERIFY_PEER) &&
3425 (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) {
3426 SSLfatal(s, SSL_AD_CERTIFICATE_REQUIRED,
3427 SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
3428 SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE);
3429 goto err;
3430 }
3431 /* No client certificate so digest cached records */
3432 if (s->s3->handshake_buffer && !ssl3_digest_cached_records(s, 0)) {
3433 /* SSLfatal() already called */
3434 goto err;
3435 }
3436 } else {
3437 EVP_PKEY *pkey;
3438 i = ssl_verify_cert_chain(s, sk);
3439 if (i <= 0) {
3440 SSLfatal(s, ssl_verify_alarm_type(s->verify_result),
3441 SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
3442 SSL_R_CERTIFICATE_VERIFY_FAILED);
3443 goto err;
3444 }
3445 if (i > 1) {
3446 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
3447 SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, i);
3448 goto err;
3449 }
3450 pkey = X509_get0_pubkey(sk_X509_value(sk, 0));
3451 if (pkey == NULL) {
3452 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE,
3453 SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
3454 SSL_R_UNKNOWN_CERTIFICATE_TYPE);
3455 goto err;
3456 }
3457 }
3458
3459 X509_free(s->session->peer);
3460 s->session->peer = sk_X509_shift(sk);
3461 s->session->verify_result = s->verify_result;
3462
3463 sk_X509_pop_free(s->session->peer_chain, X509_free);
3464 s->session->peer_chain = sk;
3465
3466 /*
3467 * Freeze the handshake buffer. For <TLS1.3 we do this after the CKE
3468 * message
3469 */
3470 if (SSL_IS_TLS13(s) && !ssl3_digest_cached_records(s, 1)) {
3471 /* SSLfatal() already called */
3472 goto err;
3473 }
3474
3475 /*
3476 * Inconsistency alert: cert_chain does *not* include the peer's own
3477 * certificate, while we do include it in statem_clnt.c
3478 */
3479 sk = NULL;
3480
3481 /* Save the current hash state for when we receive the CertificateVerify */
3482 if (SSL_IS_TLS13(s)
3483 && !ssl_handshake_hash(s, s->cert_verify_hash,
3484 sizeof(s->cert_verify_hash),
3485 &s->cert_verify_hash_len)) {
3486 /* SSLfatal() already called */
3487 goto err;
3488 }
3489
3490 ret = MSG_PROCESS_CONTINUE_READING;
3491
3492 err:
3493 X509_free(x);
3494 sk_X509_pop_free(sk, X509_free);
3495 return ret;
3496 }
3497
3498 int tls_construct_server_certificate(SSL *s, WPACKET *pkt)
3499 {
3500 CERT_PKEY *cpk = s->s3->tmp.cert;
3501
3502 if (cpk == NULL) {
3503 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3504 SSL_F_TLS_CONSTRUCT_SERVER_CERTIFICATE, ERR_R_INTERNAL_ERROR);
3505 return 0;
3506 }
3507
3508 /*
3509 * In TLSv1.3 the certificate chain is always preceded by a 0 length context
3510 * for the server Certificate message
3511 */
3512 if (SSL_IS_TLS13(s) && !WPACKET_put_bytes_u8(pkt, 0)) {
3513 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3514 SSL_F_TLS_CONSTRUCT_SERVER_CERTIFICATE, ERR_R_INTERNAL_ERROR);
3515 return 0;
3516 }
3517 if (!ssl3_output_cert_chain(s, pkt, cpk)) {
3518 /* SSLfatal() already called */
3519 return 0;
3520 }
3521
3522 return 1;
3523 }
3524
3525 int tls_construct_new_session_ticket(SSL *s, WPACKET *pkt)
3526 {
3527 unsigned char *senc = NULL;
3528 EVP_CIPHER_CTX *ctx = NULL;
3529 HMAC_CTX *hctx = NULL;
3530 unsigned char *p, *encdata1, *encdata2, *macdata1, *macdata2;
3531 const unsigned char *const_p;
3532 int len, slen_full, slen, lenfinal;
3533 SSL_SESSION *sess;
3534 unsigned int hlen;
3535 SSL_CTX *tctx = s->session_ctx;
3536 unsigned char iv[EVP_MAX_IV_LENGTH];
3537 unsigned char key_name[TLSEXT_KEYNAME_LENGTH];
3538 int iv_len;
3539 size_t macoffset, macendoffset;
3540 union {
3541 unsigned char age_add_c[sizeof(uint32_t)];
3542 uint32_t age_add;
3543 } age_add_u;
3544
3545 if (SSL_IS_TLS13(s)) {
3546 if (ssl_randbytes(s, age_add_u.age_add_c, sizeof(age_add_u)) <= 0) {
3547 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3548 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET,
3549 ERR_R_INTERNAL_ERROR);
3550 goto err;
3551 }
3552 s->session->ext.tick_age_add = age_add_u.age_add;
3553 /*
3554 * ticket_nonce is set to a single 0 byte because we only ever send a
3555 * single ticket per connection. IMPORTANT: If we ever support multiple
3556 * tickets per connection then this will need to be changed.
3557 */
3558 OPENSSL_free(s->session->ext.tick_nonce);
3559 s->session->ext.tick_nonce = OPENSSL_zalloc(sizeof(char));
3560 if (s->session->ext.tick_nonce == NULL) {
3561 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3562 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET,
3563 ERR_R_MALLOC_FAILURE);
3564 goto err;
3565 }
3566 s->session->ext.tick_nonce_len = 1;
3567 s->session->time = (long)time(NULL);
3568 if (s->s3->alpn_selected != NULL) {
3569 OPENSSL_free(s->session->ext.alpn_selected);
3570 s->session->ext.alpn_selected =
3571 OPENSSL_memdup(s->s3->alpn_selected, s->s3->alpn_selected_len);
3572 if (s->session->ext.alpn_selected == NULL) {
3573 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3574 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET,
3575 ERR_R_MALLOC_FAILURE);
3576 goto err;
3577 }
3578 s->session->ext.alpn_selected_len = s->s3->alpn_selected_len;
3579 }
3580 s->session->ext.max_early_data = s->max_early_data;
3581 }
3582
3583 /* get session encoding length */
3584 slen_full = i2d_SSL_SESSION(s->session, NULL);
3585 /*
3586 * Some length values are 16 bits, so forget it if session is too
3587 * long
3588 */
3589 if (slen_full == 0 || slen_full > 0xFF00) {
3590 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3591 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR);
3592 goto err;
3593 }
3594 senc = OPENSSL_malloc(slen_full);
3595 if (senc == NULL) {
3596 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3597 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_MALLOC_FAILURE);
3598 goto err;
3599 }
3600
3601 ctx = EVP_CIPHER_CTX_new();
3602 hctx = HMAC_CTX_new();
3603 if (ctx == NULL || hctx == NULL) {
3604 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3605 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_MALLOC_FAILURE);
3606 goto err;
3607 }
3608
3609 p = senc;
3610 if (!i2d_SSL_SESSION(s->session, &p)) {
3611 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3612 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR);
3613 goto err;
3614 }
3615
3616 /*
3617 * create a fresh copy (not shared with other threads) to clean up
3618 */
3619 const_p = senc;
3620 sess = d2i_SSL_SESSION(NULL, &const_p, slen_full);
3621 if (sess == NULL) {
3622 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3623 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR);
3624 goto err;
3625 }
3626 sess->session_id_length = 0; /* ID is irrelevant for the ticket */
3627
3628 slen = i2d_SSL_SESSION(sess, NULL);
3629 if (slen == 0 || slen > slen_full) {
3630 /* shouldn't ever happen */
3631 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3632 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR);
3633 SSL_SESSION_free(sess);
3634 goto err;
3635 }
3636 p = senc;
3637 if (!i2d_SSL_SESSION(sess, &p)) {
3638 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3639 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR);
3640 SSL_SESSION_free(sess);
3641 goto err;
3642 }
3643 SSL_SESSION_free(sess);
3644
3645 /*
3646 * Initialize HMAC and cipher contexts. If callback present it does
3647 * all the work otherwise use generated values from parent ctx.
3648 */
3649 if (tctx->ext.ticket_key_cb) {
3650 /* if 0 is returned, write an empty ticket */
3651 int ret = tctx->ext.ticket_key_cb(s, key_name, iv, ctx,
3652 hctx, 1);
3653
3654 if (ret == 0) {
3655
3656 /* Put timeout and length */
3657 if (!WPACKET_put_bytes_u32(pkt, 0)
3658 || !WPACKET_put_bytes_u16(pkt, 0)) {
3659 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3660 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET,
3661 ERR_R_INTERNAL_ERROR);
3662 goto err;
3663 }
3664 OPENSSL_free(senc);
3665 EVP_CIPHER_CTX_free(ctx);
3666 HMAC_CTX_free(hctx);
3667 return 1;
3668 }
3669 if (ret < 0) {
3670 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3671 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET,
3672 SSL_R_CALLBACK_FAILED);
3673 goto err;
3674 }
3675 iv_len = EVP_CIPHER_CTX_iv_length(ctx);
3676 } else {
3677 const EVP_CIPHER *cipher = EVP_aes_256_cbc();
3678
3679 iv_len = EVP_CIPHER_iv_length(cipher);
3680 if (ssl_randbytes(s, iv, iv_len) <= 0
3681 || !EVP_EncryptInit_ex(ctx, cipher, NULL,
3682 tctx->ext.tick_aes_key, iv)
3683 || !HMAC_Init_ex(hctx, tctx->ext.tick_hmac_key,
3684 sizeof(tctx->ext.tick_hmac_key),
3685 EVP_sha256(), NULL)) {
3686 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3687 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET,
3688 ERR_R_INTERNAL_ERROR);
3689 goto err;
3690 }
3691 memcpy(key_name, tctx->ext.tick_key_name,
3692 sizeof(tctx->ext.tick_key_name));
3693 }
3694
3695 /*
3696 * Ticket lifetime hint: For TLSv1.2 this is advisory only and we leave this
3697 * unspecified for resumed session (for simplicity).
3698 * In TLSv1.3 we reset the "time" field above, and always specify the
3699 * timeout.
3700 */
3701 if (!WPACKET_put_bytes_u32(pkt,
3702 (s->hit && !SSL_IS_TLS13(s))
3703 ? 0 : s->session->timeout)
3704 || (SSL_IS_TLS13(s)
3705 && (!WPACKET_put_bytes_u32(pkt, age_add_u.age_add)
3706 || !WPACKET_sub_memcpy_u8(pkt, s->session->ext.tick_nonce,
3707 s->session->ext.tick_nonce_len)))
3708 /* Now the actual ticket data */
3709 || !WPACKET_start_sub_packet_u16(pkt)
3710 || !WPACKET_get_total_written(pkt, &macoffset)
3711 /* Output key name */
3712 || !WPACKET_memcpy(pkt, key_name, sizeof(key_name))
3713 /* output IV */
3714 || !WPACKET_memcpy(pkt, iv, iv_len)
3715 || !WPACKET_reserve_bytes(pkt, slen + EVP_MAX_BLOCK_LENGTH,
3716 &encdata1)
3717 /* Encrypt session data */
3718 || !EVP_EncryptUpdate(ctx, encdata1, &len, senc, slen)
3719 || !WPACKET_allocate_bytes(pkt, len, &encdata2)
3720 || encdata1 != encdata2
3721 || !EVP_EncryptFinal(ctx, encdata1 + len, &lenfinal)
3722 || !WPACKET_allocate_bytes(pkt, lenfinal, &encdata2)
3723 || encdata1 + len != encdata2
3724 || len + lenfinal > slen + EVP_MAX_BLOCK_LENGTH
3725 || !WPACKET_get_total_written(pkt, &macendoffset)
3726 || !HMAC_Update(hctx,
3727 (unsigned char *)s->init_buf->data + macoffset,
3728 macendoffset - macoffset)
3729 || !WPACKET_reserve_bytes(pkt, EVP_MAX_MD_SIZE, &macdata1)
3730 || !HMAC_Final(hctx, macdata1, &hlen)
3731 || hlen > EVP_MAX_MD_SIZE
3732 || !WPACKET_allocate_bytes(pkt, hlen, &macdata2)
3733 || macdata1 != macdata2
3734 || !WPACKET_close(pkt)) {
3735 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3736 SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR);
3737 goto err;
3738 }
3739 if (SSL_IS_TLS13(s)
3740 && !tls_construct_extensions(s, pkt,
3741 SSL_EXT_TLS1_3_NEW_SESSION_TICKET,
3742 NULL, 0)) {
3743 /* SSLfatal() already called */
3744 goto err;
3745 }
3746 EVP_CIPHER_CTX_free(ctx);
3747 HMAC_CTX_free(hctx);
3748 OPENSSL_free(senc);
3749
3750 return 1;
3751 err:
3752 OPENSSL_free(senc);
3753 EVP_CIPHER_CTX_free(ctx);
3754 HMAC_CTX_free(hctx);
3755 return 0;
3756 }
3757
3758 /*
3759 * In TLSv1.3 this is called from the extensions code, otherwise it is used to
3760 * create a separate message. Returns 1 on success or 0 on failure.
3761 */
3762 int tls_construct_cert_status_body(SSL *s, WPACKET *pkt)
3763 {
3764 if (!WPACKET_put_bytes_u8(pkt, s->ext.status_type)
3765 || !WPACKET_sub_memcpy_u24(pkt, s->ext.ocsp.resp,
3766 s->ext.ocsp.resp_len)) {
3767 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_CERT_STATUS_BODY,
3768 ERR_R_INTERNAL_ERROR);
3769 return 0;
3770 }
3771
3772 return 1;
3773 }
3774
3775 int tls_construct_cert_status(SSL *s, WPACKET *pkt)
3776 {
3777 if (!tls_construct_cert_status_body(s, pkt)) {
3778 /* SSLfatal() already called */
3779 return 0;
3780 }
3781
3782 return 1;
3783 }
3784
3785 #ifndef OPENSSL_NO_NEXTPROTONEG
3786 /*
3787 * tls_process_next_proto reads a Next Protocol Negotiation handshake message.
3788 * It sets the next_proto member in s if found
3789 */
3790 MSG_PROCESS_RETURN tls_process_next_proto(SSL *s, PACKET *pkt)
3791 {
3792 PACKET next_proto, padding;
3793 size_t next_proto_len;
3794
3795 /*-
3796 * The payload looks like:
3797 * uint8 proto_len;
3798 * uint8 proto[proto_len];
3799 * uint8 padding_len;
3800 * uint8 padding[padding_len];
3801 */
3802 if (!PACKET_get_length_prefixed_1(pkt, &next_proto)
3803 || !PACKET_get_length_prefixed_1(pkt, &padding)
3804 || PACKET_remaining(pkt) > 0) {
3805 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_NEXT_PROTO,
3806 SSL_R_LENGTH_MISMATCH);
3807 return MSG_PROCESS_ERROR;
3808 }
3809
3810 if (!PACKET_memdup(&next_proto, &s->ext.npn, &next_proto_len)) {
3811 s->ext.npn_len = 0;
3812 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_NEXT_PROTO,
3813 ERR_R_INTERNAL_ERROR);
3814 return MSG_PROCESS_ERROR;
3815 }
3816
3817 s->ext.npn_len = (unsigned char)next_proto_len;
3818
3819 return MSG_PROCESS_CONTINUE_READING;
3820 }
3821 #endif
3822
3823 static int tls_construct_encrypted_extensions(SSL *s, WPACKET *pkt)
3824 {
3825 if (!tls_construct_extensions(s, pkt, SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
3826 NULL, 0)) {
3827 /* SSLfatal() already called */
3828 return 0;
3829 }
3830
3831 return 1;
3832 }
3833
3834 static int tls_construct_hello_retry_request(SSL *s, WPACKET *pkt)
3835 {
3836 size_t len = 0;
3837
3838 /*
3839 * TODO(TLS1.3): Remove the DRAFT version before release
3840 * (should be s->version)
3841 */
3842 if (!WPACKET_put_bytes_u16(pkt, TLS1_3_VERSION_DRAFT)
3843 || !s->method->put_cipher_by_char(s->s3->tmp.new_cipher, pkt,
3844 &len)) {
3845 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
3846 SSL_F_TLS_CONSTRUCT_HELLO_RETRY_REQUEST, ERR_R_INTERNAL_ERROR);
3847 return 0;
3848 }
3849
3850 if (!tls_construct_extensions(s, pkt, SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST,
3851 NULL, 0)) {
3852 /* SSLfatal() already called */
3853 return 0;
3854 }
3855
3856 /* Ditch the session. We'll create a new one next time around */
3857 SSL_SESSION_free(s->session);
3858 s->session = NULL;
3859 s->hit = 0;
3860
3861 /*
3862 * Re-initialise the Transcript Hash. We're going to prepopulate it with
3863 * a synthetic message_hash in place of ClientHello1.
3864 */
3865 if (!create_synthetic_message_hash(s)) {
3866 /* SSLfatal() already called */
3867 return 0;
3868 }
3869
3870 return 1;
3871 }
3872
3873 MSG_PROCESS_RETURN tls_process_end_of_early_data(SSL *s, PACKET *pkt)
3874 {
3875 if (PACKET_remaining(pkt) != 0) {
3876 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PROCESS_END_OF_EARLY_DATA,
3877 SSL_R_LENGTH_MISMATCH);
3878 return MSG_PROCESS_ERROR;
3879 }
3880
3881 if (s->early_data_state != SSL_EARLY_DATA_READING
3882 && s->early_data_state != SSL_EARLY_DATA_READ_RETRY) {
3883 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PROCESS_END_OF_EARLY_DATA,
3884 ERR_R_INTERNAL_ERROR);
3885 return MSG_PROCESS_ERROR;
3886 }
3887
3888 /*
3889 * EndOfEarlyData signals a key change so the end of the message must be on
3890 * a record boundary.
3891 */
3892 if (RECORD_LAYER_processed_read_pending(&s->rlayer)) {
3893 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE,
3894 SSL_F_TLS_PROCESS_END_OF_EARLY_DATA,
3895 SSL_R_NOT_ON_RECORD_BOUNDARY);
3896 return MSG_PROCESS_ERROR;
3897 }
3898
3899 s->early_data_state = SSL_EARLY_DATA_FINISHED_READING;
3900 if (!s->method->ssl3_enc->change_cipher_state(s,
3901 SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_SERVER_READ)) {
3902 /* SSLfatal() already called */
3903 return MSG_PROCESS_ERROR;
3904 }
3905
3906 return MSG_PROCESS_CONTINUE_READING;
3907 }