2 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
10 /* ====================================================================
11 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
13 * Portions of the attached software ("Contribution") are developed by
14 * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project.
16 * The Contribution is licensed pursuant to the OpenSSL open source
17 * license provided above.
19 * ECC cipher suite support in OpenSSL originally written by
20 * Vipul Gupta and Sumit Gupta of Sun Microsystems Laboratories.
23 /* ====================================================================
24 * Copyright 2005 Nokia. All rights reserved.
26 * The portions of the attached software ("Contribution") is developed by
27 * Nokia Corporation and is licensed pursuant to the OpenSSL open source
30 * The Contribution, originally written by Mika Kousa and Pasi Eronen of
31 * Nokia Corporation, consists of the "PSK" (Pre-Shared Key) ciphersuites
32 * support (see RFC 4279) to OpenSSL.
34 * No patent licenses or other rights except those expressly stated in
35 * the OpenSSL open source license shall be deemed granted or received
36 * expressly, by implication, estoppel, or otherwise.
38 * No assurances are provided by Nokia that the Contribution does not
39 * infringe the patent or other intellectual property rights of any third
40 * party or that the license provides you with all the necessary rights
41 * to make use of the Contribution.
43 * THE SOFTWARE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. IN
44 * ADDITION TO THE DISCLAIMERS INCLUDED IN THE LICENSE, NOKIA
45 * SPECIFICALLY DISCLAIMS ANY LIABILITY FOR CLAIMS BROUGHT BY YOU OR ANY
46 * OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OR
51 #include "../ssl_locl.h"
52 #include "statem_locl.h"
53 #include "internal/constant_time_locl.h"
54 #include <openssl/buffer.h>
55 #include <openssl/rand.h>
56 #include <openssl/objects.h>
57 #include <openssl/evp.h>
58 #include <openssl/hmac.h>
59 #include <openssl/x509.h>
60 #include <openssl/dh.h>
61 #include <openssl/bn.h>
62 #include <openssl/md5.h>
64 static int tls_construct_encrypted_extensions(SSL *s, WPACKET *pkt);
65 static STACK_OF(SSL_CIPHER) *ssl_bytes_to_cipher_list(SSL *s,
66 PACKET *cipher_suites,
68 **skp, int sslv2format,
72 * ossl_statem_server13_read_transition() encapsulates the logic for the allowed
73 * handshake state transitions when a TLSv1.3 server is reading messages from
74 * the client. The message type that the client has sent is provided in |mt|.
75 * The current state is in |s->statem.hand_state|.
77 * Return values are 1 for success (transition allowed) and 0 on error
78 * (transition not allowed)
80 static int ossl_statem_server13_read_transition(SSL *s, int mt)
82 OSSL_STATEM *st = &s->statem;
85 * TODO(TLS1.3): This is still based on the TLSv1.2 state machine. Over time
86 * we will update this to look more like real TLSv1.3
90 * Note: There is no case for TLS_ST_BEFORE because at that stage we have
91 * not negotiated TLSv1.3 yet, so that case is handled by
92 * ossl_statem_server_read_transition()
94 switch (st->hand_state) {
98 case TLS_ST_SW_FINISHED:
99 if (s->s3->tmp.cert_request) {
100 if (mt == SSL3_MT_CERTIFICATE) {
101 st->hand_state = TLS_ST_SR_CERT;
105 if (mt == SSL3_MT_FINISHED) {
106 st->hand_state = TLS_ST_SR_FINISHED;
113 if (s->session->peer == NULL) {
114 if (mt == SSL3_MT_FINISHED) {
115 st->hand_state = TLS_ST_SR_FINISHED;
119 if (mt == SSL3_MT_CERTIFICATE_VERIFY) {
120 st->hand_state = TLS_ST_SR_CERT_VRFY;
126 case TLS_ST_SR_CERT_VRFY:
127 if (mt == SSL3_MT_FINISHED) {
128 st->hand_state = TLS_ST_SR_FINISHED;
134 /* No valid transition found */
135 ssl3_send_alert(s, SSL3_AL_FATAL, SSL3_AD_UNEXPECTED_MESSAGE);
136 SSLerr(SSL_F_OSSL_STATEM_SERVER13_READ_TRANSITION,
137 SSL_R_UNEXPECTED_MESSAGE);
142 * ossl_statem_server_read_transition() encapsulates the logic for the allowed
143 * handshake state transitions when the server is reading messages from the
144 * client. The message type that the client has sent is provided in |mt|. The
145 * current state is in |s->statem.hand_state|.
147 * Return values are 1 for success (transition allowed) and 0 on error
148 * (transition not allowed)
150 int ossl_statem_server_read_transition(SSL *s, int mt)
152 OSSL_STATEM *st = &s->statem;
154 if (SSL_IS_TLS13(s)) {
155 if (!ossl_statem_server13_read_transition(s, mt))
160 switch (st->hand_state) {
165 case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
166 if (mt == SSL3_MT_CLIENT_HELLO) {
167 st->hand_state = TLS_ST_SR_CLNT_HELLO;
172 case TLS_ST_SW_SRVR_DONE:
174 * If we get a CKE message after a ServerDone then either
175 * 1) We didn't request a Certificate
177 * 2) If we did request one then
178 * a) We allow no Certificate to be returned
180 * b) We are running SSL3 (in TLS1.0+ the client must return a 0
181 * list if we requested a certificate)
183 if (mt == SSL3_MT_CLIENT_KEY_EXCHANGE) {
184 if (s->s3->tmp.cert_request) {
185 if (s->version == SSL3_VERSION) {
186 if ((s->verify_mode & SSL_VERIFY_PEER)
187 && (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) {
189 * This isn't an unexpected message as such - we're just
190 * not going to accept it because we require a client
193 ssl3_send_alert(s, SSL3_AL_FATAL,
194 SSL3_AD_HANDSHAKE_FAILURE);
195 SSLerr(SSL_F_OSSL_STATEM_SERVER_READ_TRANSITION,
196 SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE);
199 st->hand_state = TLS_ST_SR_KEY_EXCH;
203 st->hand_state = TLS_ST_SR_KEY_EXCH;
206 } else if (s->s3->tmp.cert_request) {
207 if (mt == SSL3_MT_CERTIFICATE) {
208 st->hand_state = TLS_ST_SR_CERT;
215 if (mt == SSL3_MT_CLIENT_KEY_EXCHANGE) {
216 st->hand_state = TLS_ST_SR_KEY_EXCH;
221 case TLS_ST_SR_KEY_EXCH:
223 * We should only process a CertificateVerify message if we have
224 * received a Certificate from the client. If so then |s->session->peer|
225 * will be non NULL. In some instances a CertificateVerify message is
226 * not required even if the peer has sent a Certificate (e.g. such as in
227 * the case of static DH). In that case |st->no_cert_verify| should be
230 if (s->session->peer == NULL || st->no_cert_verify) {
231 if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
233 * For the ECDH ciphersuites when the client sends its ECDH
234 * pub key in a certificate, the CertificateVerify message is
235 * not sent. Also for GOST ciphersuites when the client uses
236 * its key from the certificate for key exchange.
238 st->hand_state = TLS_ST_SR_CHANGE;
242 if (mt == SSL3_MT_CERTIFICATE_VERIFY) {
243 st->hand_state = TLS_ST_SR_CERT_VRFY;
249 case TLS_ST_SR_CERT_VRFY:
250 if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
251 st->hand_state = TLS_ST_SR_CHANGE;
256 case TLS_ST_SR_CHANGE:
257 #ifndef OPENSSL_NO_NEXTPROTONEG
258 if (s->s3->npn_seen) {
259 if (mt == SSL3_MT_NEXT_PROTO) {
260 st->hand_state = TLS_ST_SR_NEXT_PROTO;
265 if (mt == SSL3_MT_FINISHED) {
266 st->hand_state = TLS_ST_SR_FINISHED;
269 #ifndef OPENSSL_NO_NEXTPROTONEG
274 #ifndef OPENSSL_NO_NEXTPROTONEG
275 case TLS_ST_SR_NEXT_PROTO:
276 if (mt == SSL3_MT_FINISHED) {
277 st->hand_state = TLS_ST_SR_FINISHED;
283 case TLS_ST_SW_FINISHED:
284 if (mt == SSL3_MT_CHANGE_CIPHER_SPEC) {
285 st->hand_state = TLS_ST_SR_CHANGE;
292 /* No valid transition found */
293 ssl3_send_alert(s, SSL3_AL_FATAL, SSL3_AD_UNEXPECTED_MESSAGE);
294 SSLerr(SSL_F_OSSL_STATEM_SERVER_READ_TRANSITION, SSL_R_UNEXPECTED_MESSAGE);
299 * Should we send a ServerKeyExchange message?
301 * Valid return values are:
305 static int send_server_key_exchange(SSL *s)
307 unsigned long alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
310 * only send a ServerKeyExchange if DH or fortezza but we have a
311 * sign only certificate PSK: may send PSK identity hints For
312 * ECC ciphersuites, we send a serverKeyExchange message only if
313 * the cipher suite is either ECDH-anon or ECDHE. In other cases,
314 * the server certificate contains the server's public key for
317 if (alg_k & (SSL_kDHE | SSL_kECDHE)
319 * PSK: send ServerKeyExchange if PSK identity hint if
322 #ifndef OPENSSL_NO_PSK
323 /* Only send SKE if we have identity hint for plain PSK */
324 || ((alg_k & (SSL_kPSK | SSL_kRSAPSK))
325 && s->cert->psk_identity_hint)
326 /* For other PSK always send SKE */
327 || (alg_k & (SSL_PSK & (SSL_kDHEPSK | SSL_kECDHEPSK)))
329 #ifndef OPENSSL_NO_SRP
330 /* SRP: send ServerKeyExchange */
331 || (alg_k & SSL_kSRP)
341 * Should we send a CertificateRequest message?
343 * Valid return values are:
347 static int send_certificate_request(SSL *s)
350 /* don't request cert unless asked for it: */
351 s->verify_mode & SSL_VERIFY_PEER
353 * if SSL_VERIFY_CLIENT_ONCE is set, don't request cert
354 * during re-negotiation:
356 && (s->s3->tmp.finish_md_len == 0 ||
357 !(s->verify_mode & SSL_VERIFY_CLIENT_ONCE))
359 * never request cert in anonymous ciphersuites (see
360 * section "Certificate request" in SSL 3 drafts and in
363 && (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL)
365 * ... except when the application insists on
366 * verification (against the specs, but statem_clnt.c accepts
369 || (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT))
370 /* don't request certificate for SRP auth */
371 && !(s->s3->tmp.new_cipher->algorithm_auth & SSL_aSRP)
373 * With normal PSK Certificates and Certificate Requests
376 && !(s->s3->tmp.new_cipher->algorithm_auth & SSL_aPSK)) {
384 * ossl_statem_server13_write_transition() works out what handshake state to
385 * move to next when a TLSv1.3 server is writing messages to be sent to the
388 static WRITE_TRAN ossl_statem_server13_write_transition(SSL *s)
390 OSSL_STATEM *st = &s->statem;
393 * TODO(TLS1.3): This is still based on the TLSv1.2 state machine. Over time
394 * we will update this to look more like real TLSv1.3
398 * No case for TLS_ST_BEFORE, because at that stage we have not negotiated
399 * TLSv1.3 yet, so that is handled by ossl_statem_server_write_transition()
402 switch (st->hand_state) {
404 /* Shouldn't happen */
405 return WRITE_TRAN_ERROR;
407 case TLS_ST_SR_CLNT_HELLO:
408 st->hand_state = TLS_ST_SW_SRVR_HELLO;
409 return WRITE_TRAN_CONTINUE;
411 case TLS_ST_SW_SRVR_HELLO:
412 st->hand_state = TLS_ST_SW_ENCRYPTED_EXTENSIONS;
413 return WRITE_TRAN_CONTINUE;
415 case TLS_ST_SW_ENCRYPTED_EXTENSIONS:
417 st->hand_state = TLS_ST_SW_FINISHED;
418 else if (send_certificate_request(s))
419 st->hand_state = TLS_ST_SW_CERT_REQ;
421 st->hand_state = TLS_ST_SW_CERT;
423 return WRITE_TRAN_CONTINUE;
425 case TLS_ST_SW_CERT_REQ:
426 st->hand_state = TLS_ST_SW_CERT;
427 return WRITE_TRAN_CONTINUE;
430 st->hand_state = TLS_ST_SW_CERT_VRFY;
431 return WRITE_TRAN_CONTINUE;
433 case TLS_ST_SW_CERT_VRFY:
434 st->hand_state = TLS_ST_SW_FINISHED;
435 return WRITE_TRAN_CONTINUE;
437 case TLS_ST_SW_FINISHED:
438 return WRITE_TRAN_FINISHED;
440 case TLS_ST_SR_FINISHED:
441 st->hand_state = TLS_ST_OK;
442 ossl_statem_set_in_init(s, 0);
443 return WRITE_TRAN_CONTINUE;
448 * ossl_statem_server_write_transition() works out what handshake state to move
449 * to next when the server is writing messages to be sent to the client.
451 WRITE_TRAN ossl_statem_server_write_transition(SSL *s)
453 OSSL_STATEM *st = &s->statem;
456 * Note that before the ClientHello we don't know what version we are going
457 * to negotiate yet, so we don't take this branch until later
461 return ossl_statem_server13_write_transition(s);
463 switch (st->hand_state) {
465 /* Shouldn't happen */
466 return WRITE_TRAN_ERROR;
469 /* Just go straight to trying to read from the client */
470 return WRITE_TRAN_FINISHED;
473 /* We must be trying to renegotiate */
474 st->hand_state = TLS_ST_SW_HELLO_REQ;
475 return WRITE_TRAN_CONTINUE;
477 case TLS_ST_SW_HELLO_REQ:
478 st->hand_state = TLS_ST_OK;
479 ossl_statem_set_in_init(s, 0);
480 return WRITE_TRAN_CONTINUE;
482 case TLS_ST_SR_CLNT_HELLO:
483 if (SSL_IS_DTLS(s) && !s->d1->cookie_verified
484 && (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))
485 st->hand_state = DTLS_ST_SW_HELLO_VERIFY_REQUEST;
487 st->hand_state = TLS_ST_SW_SRVR_HELLO;
488 return WRITE_TRAN_CONTINUE;
490 case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
491 return WRITE_TRAN_FINISHED;
493 case TLS_ST_SW_SRVR_HELLO:
495 if (s->ext.ticket_expected)
496 st->hand_state = TLS_ST_SW_SESSION_TICKET;
498 st->hand_state = TLS_ST_SW_CHANGE;
500 /* Check if it is anon DH or anon ECDH, */
501 /* normal PSK or SRP */
502 if (!(s->s3->tmp.new_cipher->algorithm_auth &
503 (SSL_aNULL | SSL_aSRP | SSL_aPSK))) {
504 st->hand_state = TLS_ST_SW_CERT;
505 } else if (send_server_key_exchange(s)) {
506 st->hand_state = TLS_ST_SW_KEY_EXCH;
507 } else if (send_certificate_request(s)) {
508 st->hand_state = TLS_ST_SW_CERT_REQ;
510 st->hand_state = TLS_ST_SW_SRVR_DONE;
513 return WRITE_TRAN_CONTINUE;
516 if (s->ext.status_expected) {
517 st->hand_state = TLS_ST_SW_CERT_STATUS;
518 return WRITE_TRAN_CONTINUE;
522 case TLS_ST_SW_CERT_STATUS:
523 if (send_server_key_exchange(s)) {
524 st->hand_state = TLS_ST_SW_KEY_EXCH;
525 return WRITE_TRAN_CONTINUE;
529 case TLS_ST_SW_KEY_EXCH:
530 if (send_certificate_request(s)) {
531 st->hand_state = TLS_ST_SW_CERT_REQ;
532 return WRITE_TRAN_CONTINUE;
536 case TLS_ST_SW_CERT_REQ:
537 st->hand_state = TLS_ST_SW_SRVR_DONE;
538 return WRITE_TRAN_CONTINUE;
540 case TLS_ST_SW_SRVR_DONE:
541 return WRITE_TRAN_FINISHED;
543 case TLS_ST_SR_FINISHED:
545 st->hand_state = TLS_ST_OK;
546 ossl_statem_set_in_init(s, 0);
547 return WRITE_TRAN_CONTINUE;
548 } else if (s->ext.ticket_expected) {
549 st->hand_state = TLS_ST_SW_SESSION_TICKET;
551 st->hand_state = TLS_ST_SW_CHANGE;
553 return WRITE_TRAN_CONTINUE;
555 case TLS_ST_SW_SESSION_TICKET:
556 st->hand_state = TLS_ST_SW_CHANGE;
557 return WRITE_TRAN_CONTINUE;
559 case TLS_ST_SW_CHANGE:
560 st->hand_state = TLS_ST_SW_FINISHED;
561 return WRITE_TRAN_CONTINUE;
563 case TLS_ST_SW_FINISHED:
565 return WRITE_TRAN_FINISHED;
567 st->hand_state = TLS_ST_OK;
568 ossl_statem_set_in_init(s, 0);
569 return WRITE_TRAN_CONTINUE;
574 * Perform any pre work that needs to be done prior to sending a message from
575 * the server to the client.
577 WORK_STATE ossl_statem_server_pre_work(SSL *s, WORK_STATE wst)
579 OSSL_STATEM *st = &s->statem;
581 switch (st->hand_state) {
583 /* No pre work to be done */
586 case TLS_ST_SW_HELLO_REQ:
589 dtls1_clear_sent_buffer(s);
592 case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
594 if (SSL_IS_DTLS(s)) {
595 dtls1_clear_sent_buffer(s);
596 /* We don't buffer this message so don't use the timer */
601 case TLS_ST_SW_SRVR_HELLO:
602 if (SSL_IS_DTLS(s)) {
604 * Messages we write from now on should be bufferred and
605 * retransmitted if necessary, so we need to use the timer now
611 case TLS_ST_SW_SRVR_DONE:
612 #ifndef OPENSSL_NO_SCTP
613 if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s)))
614 return dtls_wait_for_dry(s);
616 return WORK_FINISHED_CONTINUE;
618 case TLS_ST_SW_SESSION_TICKET:
619 if (SSL_IS_DTLS(s)) {
621 * We're into the last flight. We don't retransmit the last flight
622 * unless we need to, so we don't use the timer
628 case TLS_ST_SW_CHANGE:
629 s->session->cipher = s->s3->tmp.new_cipher;
630 if (!s->method->ssl3_enc->setup_key_block(s)) {
631 ossl_statem_set_error(s);
634 if (SSL_IS_DTLS(s)) {
636 * We're into the last flight. We don't retransmit the last flight
637 * unless we need to, so we don't use the timer. This might have
638 * already been set to 0 if we sent a NewSessionTicket message,
639 * but we'll set it again here in case we didn't.
643 return WORK_FINISHED_CONTINUE;
646 return tls_finish_handshake(s, wst);
649 return WORK_FINISHED_CONTINUE;
653 * Perform any work that needs to be done after sending a message from the
654 * server to the client.
656 WORK_STATE ossl_statem_server_post_work(SSL *s, WORK_STATE wst)
658 OSSL_STATEM *st = &s->statem;
662 switch (st->hand_state) {
664 /* No post work to be done */
667 case TLS_ST_SW_HELLO_REQ:
668 if (statem_flush(s) != 1)
670 if (!ssl3_init_finished_mac(s)) {
671 ossl_statem_set_error(s);
676 case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
677 if (statem_flush(s) != 1)
679 /* HelloVerifyRequest resets Finished MAC */
680 if (s->version != DTLS1_BAD_VER && !ssl3_init_finished_mac(s)) {
681 ossl_statem_set_error(s);
685 * The next message should be another ClientHello which we need to
686 * treat like it was the first packet
691 case TLS_ST_SW_SRVR_HELLO:
692 #ifndef OPENSSL_NO_SCTP
693 if (SSL_IS_DTLS(s) && s->hit) {
694 unsigned char sctpauthkey[64];
695 char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
698 * Add new shared key for SCTP-Auth, will be ignored if no
701 memcpy(labelbuffer, DTLS1_SCTP_AUTH_LABEL,
702 sizeof(DTLS1_SCTP_AUTH_LABEL));
704 if (SSL_export_keying_material(s, sctpauthkey,
705 sizeof(sctpauthkey), labelbuffer,
706 sizeof(labelbuffer), NULL, 0,
708 ossl_statem_set_error(s);
712 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
713 sizeof(sctpauthkey), sctpauthkey);
717 * TODO(TLS1.3): This actually causes a problem. We don't yet know
718 * whether the next record we are going to receive is an unencrypted
719 * alert, or an encrypted handshake message. We're going to need
720 * something clever in the record layer for this.
722 if (SSL_IS_TLS13(s)) {
723 if (!s->method->ssl3_enc->setup_key_block(s)
724 || !s->method->ssl3_enc->change_cipher_state(s,
725 SSL3_CC_HANDSHAKE | SSL3_CHANGE_CIPHER_SERVER_WRITE)
726 || !s->method->ssl3_enc->change_cipher_state(s,
727 SSL3_CC_HANDSHAKE |SSL3_CHANGE_CIPHER_SERVER_READ))
732 case TLS_ST_SW_CHANGE:
733 #ifndef OPENSSL_NO_SCTP
734 if (SSL_IS_DTLS(s) && !s->hit) {
736 * Change to new shared key of SCTP-Auth, will be ignored if
739 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
743 if (!s->method->ssl3_enc->change_cipher_state(s,
744 SSL3_CHANGE_CIPHER_SERVER_WRITE))
746 ossl_statem_set_error(s);
751 dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
754 case TLS_ST_SW_SRVR_DONE:
755 if (statem_flush(s) != 1)
759 case TLS_ST_SW_FINISHED:
760 if (statem_flush(s) != 1)
762 #ifndef OPENSSL_NO_SCTP
763 if (SSL_IS_DTLS(s) && s->hit) {
765 * Change to new shared key of SCTP-Auth, will be ignored if
768 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
772 if (SSL_IS_TLS13(s)) {
773 if (!s->method->ssl3_enc->generate_master_secret(s,
774 s->session->master_key, s->handshake_secret, 0,
775 &s->session->master_key_length)
776 || !s->method->ssl3_enc->change_cipher_state(s,
777 SSL3_CC_APPLICATION | SSL3_CHANGE_CIPHER_SERVER_WRITE))
783 return WORK_FINISHED_CONTINUE;
787 * Get the message construction function and message type for sending from the
790 * Valid return values are:
794 int ossl_statem_server_construct_message(SSL *s, WPACKET *pkt,
795 confunc_f *confunc, int *mt)
797 OSSL_STATEM *st = &s->statem;
799 switch (st->hand_state) {
801 /* Shouldn't happen */
804 case TLS_ST_SW_CHANGE:
806 *confunc = dtls_construct_change_cipher_spec;
808 *confunc = tls_construct_change_cipher_spec;
809 *mt = SSL3_MT_CHANGE_CIPHER_SPEC;
812 case DTLS_ST_SW_HELLO_VERIFY_REQUEST:
813 *confunc = dtls_construct_hello_verify_request;
814 *mt = DTLS1_MT_HELLO_VERIFY_REQUEST;
817 case TLS_ST_SW_HELLO_REQ:
818 /* No construction function needed */
820 *mt = SSL3_MT_HELLO_REQUEST;
823 case TLS_ST_SW_SRVR_HELLO:
824 *confunc = tls_construct_server_hello;
825 *mt = SSL3_MT_SERVER_HELLO;
829 *confunc = tls_construct_server_certificate;
830 *mt = SSL3_MT_CERTIFICATE;
833 case TLS_ST_SW_CERT_VRFY:
834 *confunc = tls_construct_cert_verify;
835 *mt = SSL3_MT_CERTIFICATE_VERIFY;
839 case TLS_ST_SW_KEY_EXCH:
840 *confunc = tls_construct_server_key_exchange;
841 *mt = SSL3_MT_SERVER_KEY_EXCHANGE;
844 case TLS_ST_SW_CERT_REQ:
845 *confunc = tls_construct_certificate_request;
846 *mt = SSL3_MT_CERTIFICATE_REQUEST;
849 case TLS_ST_SW_SRVR_DONE:
850 *confunc = tls_construct_server_done;
851 *mt = SSL3_MT_SERVER_DONE;
854 case TLS_ST_SW_SESSION_TICKET:
855 *confunc = tls_construct_new_session_ticket;
856 *mt = SSL3_MT_NEWSESSION_TICKET;
859 case TLS_ST_SW_CERT_STATUS:
860 *confunc = tls_construct_cert_status;
861 *mt = SSL3_MT_CERTIFICATE_STATUS;
864 case TLS_ST_SW_FINISHED:
865 *confunc = tls_construct_finished;
866 *mt = SSL3_MT_FINISHED;
869 case TLS_ST_SW_ENCRYPTED_EXTENSIONS:
870 *confunc = tls_construct_encrypted_extensions;
871 *mt = SSL3_MT_ENCRYPTED_EXTENSIONS;
879 * Maximum size (excluding the Handshake header) of a ClientHello message,
880 * calculated as follows:
882 * 2 + # client_version
883 * 32 + # only valid length for random
884 * 1 + # length of session_id
885 * 32 + # maximum size for session_id
886 * 2 + # length of cipher suites
887 * 2^16-2 + # maximum length of cipher suites array
888 * 1 + # length of compression_methods
889 * 2^8-1 + # maximum length of compression methods
890 * 2 + # length of extensions
891 * 2^16-1 # maximum length of extensions
893 #define CLIENT_HELLO_MAX_LENGTH 131396
895 #define CLIENT_KEY_EXCH_MAX_LENGTH 2048
896 #define NEXT_PROTO_MAX_LENGTH 514
899 * Returns the maximum allowed length for the current message that we are
900 * reading. Excludes the message header.
902 size_t ossl_statem_server_max_message_size(SSL *s)
904 OSSL_STATEM *st = &s->statem;
906 switch (st->hand_state) {
908 /* Shouldn't happen */
911 case TLS_ST_SR_CLNT_HELLO:
912 return CLIENT_HELLO_MAX_LENGTH;
915 return s->max_cert_list;
917 case TLS_ST_SR_KEY_EXCH:
918 return CLIENT_KEY_EXCH_MAX_LENGTH;
920 case TLS_ST_SR_CERT_VRFY:
921 return SSL3_RT_MAX_PLAIN_LENGTH;
923 #ifndef OPENSSL_NO_NEXTPROTONEG
924 case TLS_ST_SR_NEXT_PROTO:
925 return NEXT_PROTO_MAX_LENGTH;
928 case TLS_ST_SR_CHANGE:
929 return CCS_MAX_LENGTH;
931 case TLS_ST_SR_FINISHED:
932 return FINISHED_MAX_LENGTH;
937 * Process a message that the server has received from the client.
939 MSG_PROCESS_RETURN ossl_statem_server_process_message(SSL *s, PACKET *pkt)
941 OSSL_STATEM *st = &s->statem;
943 switch (st->hand_state) {
945 /* Shouldn't happen */
946 return MSG_PROCESS_ERROR;
948 case TLS_ST_SR_CLNT_HELLO:
949 return tls_process_client_hello(s, pkt);
952 return tls_process_client_certificate(s, pkt);
954 case TLS_ST_SR_KEY_EXCH:
955 return tls_process_client_key_exchange(s, pkt);
957 case TLS_ST_SR_CERT_VRFY:
958 return tls_process_cert_verify(s, pkt);
960 #ifndef OPENSSL_NO_NEXTPROTONEG
961 case TLS_ST_SR_NEXT_PROTO:
962 return tls_process_next_proto(s, pkt);
965 case TLS_ST_SR_CHANGE:
966 return tls_process_change_cipher_spec(s, pkt);
968 case TLS_ST_SR_FINISHED:
969 return tls_process_finished(s, pkt);
974 * Perform any further processing required following the receipt of a message
977 WORK_STATE ossl_statem_server_post_process_message(SSL *s, WORK_STATE wst)
979 OSSL_STATEM *st = &s->statem;
981 switch (st->hand_state) {
983 /* Shouldn't happen */
986 case TLS_ST_SR_CLNT_HELLO:
987 return tls_post_process_client_hello(s, wst);
989 case TLS_ST_SR_KEY_EXCH:
990 return tls_post_process_client_key_exchange(s, wst);
992 case TLS_ST_SR_CERT_VRFY:
993 #ifndef OPENSSL_NO_SCTP
994 if ( /* Is this SCTP? */
995 BIO_dgram_is_sctp(SSL_get_wbio(s))
996 /* Are we renegotiating? */
997 && s->renegotiate && BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
998 s->s3->in_read_app_data = 2;
999 s->rwstate = SSL_READING;
1000 BIO_clear_retry_flags(SSL_get_rbio(s));
1001 BIO_set_retry_read(SSL_get_rbio(s));
1002 ossl_statem_set_sctp_read_sock(s, 1);
1005 ossl_statem_set_sctp_read_sock(s, 0);
1008 return WORK_FINISHED_CONTINUE;
1010 return WORK_FINISHED_CONTINUE;
1013 #ifndef OPENSSL_NO_SRP
1014 static int ssl_check_srp_ext_ClientHello(SSL *s, int *al)
1016 int ret = SSL_ERROR_NONE;
1018 *al = SSL_AD_UNRECOGNIZED_NAME;
1020 if ((s->s3->tmp.new_cipher->algorithm_mkey & SSL_kSRP) &&
1021 (s->srp_ctx.TLS_ext_srp_username_callback != NULL)) {
1022 if (s->srp_ctx.login == NULL) {
1024 * RFC 5054 says SHOULD reject, we do so if There is no srp
1027 ret = SSL3_AL_FATAL;
1028 *al = SSL_AD_UNKNOWN_PSK_IDENTITY;
1030 ret = SSL_srp_server_param_with_username(s, al);
1037 int dtls_raw_hello_verify_request(WPACKET *pkt, unsigned char *cookie,
1040 /* Always use DTLS 1.0 version: see RFC 6347 */
1041 if (!WPACKET_put_bytes_u16(pkt, DTLS1_VERSION)
1042 || !WPACKET_sub_memcpy_u8(pkt, cookie, cookie_len))
1048 int dtls_construct_hello_verify_request(SSL *s, WPACKET *pkt)
1050 unsigned int cookie_leni;
1051 if (s->ctx->app_gen_cookie_cb == NULL ||
1052 s->ctx->app_gen_cookie_cb(s, s->d1->cookie,
1053 &cookie_leni) == 0 ||
1054 cookie_leni > 255) {
1055 SSLerr(SSL_F_DTLS_CONSTRUCT_HELLO_VERIFY_REQUEST,
1056 SSL_R_COOKIE_GEN_CALLBACK_FAILURE);
1059 s->d1->cookie_len = cookie_leni;
1061 if (!dtls_raw_hello_verify_request(pkt, s->d1->cookie,
1062 s->d1->cookie_len)) {
1063 SSLerr(SSL_F_DTLS_CONSTRUCT_HELLO_VERIFY_REQUEST, ERR_R_INTERNAL_ERROR);
1070 #ifndef OPENSSL_NO_EC
1072 * ssl_check_for_safari attempts to fingerprint Safari using OS X
1073 * SecureTransport using the TLS extension block in |hello|.
1074 * Safari, since 10.6, sends exactly these extensions, in this order:
1079 * We wish to fingerprint Safari because they broke ECDHE-ECDSA support in 10.8,
1080 * but they advertise support. So enabling ECDHE-ECDSA ciphers breaks them.
1081 * Sadly we cannot differentiate 10.6, 10.7 and 10.8.4 (which work), from
1082 * 10.8..10.8.3 (which don't work).
1084 static void ssl_check_for_safari(SSL *s, const CLIENTHELLO_MSG *hello)
1086 static const unsigned char kSafariExtensionsBlock[] = {
1087 0x00, 0x0a, /* elliptic_curves extension */
1088 0x00, 0x08, /* 8 bytes */
1089 0x00, 0x06, /* 6 bytes of curve ids */
1090 0x00, 0x17, /* P-256 */
1091 0x00, 0x18, /* P-384 */
1092 0x00, 0x19, /* P-521 */
1094 0x00, 0x0b, /* ec_point_formats */
1095 0x00, 0x02, /* 2 bytes */
1096 0x01, /* 1 point format */
1097 0x00, /* uncompressed */
1098 /* The following is only present in TLS 1.2 */
1099 0x00, 0x0d, /* signature_algorithms */
1100 0x00, 0x0c, /* 12 bytes */
1101 0x00, 0x0a, /* 10 bytes */
1102 0x05, 0x01, /* SHA-384/RSA */
1103 0x04, 0x01, /* SHA-256/RSA */
1104 0x02, 0x01, /* SHA-1/RSA */
1105 0x04, 0x03, /* SHA-256/ECDSA */
1106 0x02, 0x03, /* SHA-1/ECDSA */
1108 /* Length of the common prefix (first two extensions). */
1109 static const size_t kSafariCommonExtensionsLength = 18;
1114 tmppkt = hello->extensions;
1116 if (!PACKET_forward(&tmppkt, 2)
1117 || !PACKET_get_net_2(&tmppkt, &type)
1118 || !PACKET_get_length_prefixed_2(&tmppkt, &sni)) {
1122 if (type != TLSEXT_TYPE_server_name)
1125 ext_len = TLS1_get_client_version(s) >= TLS1_2_VERSION ?
1126 sizeof(kSafariExtensionsBlock) : kSafariCommonExtensionsLength;
1128 s->s3->is_probably_safari = PACKET_equal(&tmppkt, kSafariExtensionsBlock,
1131 #endif /* !OPENSSL_NO_EC */
1133 MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
1135 int i, al = SSL_AD_INTERNAL_ERROR;
1139 const SSL_CIPHER *c;
1140 #ifndef OPENSSL_NO_COMP
1141 SSL_COMP *comp = NULL;
1143 STACK_OF(SSL_CIPHER) *ciphers = NULL;
1145 /* |cookie| will only be initialized for DTLS. */
1146 PACKET session_id, compression, extensions, cookie;
1147 static const unsigned char null_compression = 0;
1148 CLIENTHELLO_MSG clienthello;
1151 * First, parse the raw ClientHello data into the CLIENTHELLO_MSG structure.
1153 memset(&clienthello, 0, sizeof(clienthello));
1154 clienthello.isv2 = RECORD_LAYER_is_sslv2_record(&s->rlayer);
1155 PACKET_null_init(&cookie);
1157 if (clienthello.isv2) {
1161 * An SSLv3/TLSv1 backwards-compatible CLIENT-HELLO in an SSLv2
1162 * header is sent directly on the wire, not wrapped as a TLS
1163 * record. Our record layer just processes the message length and passes
1164 * the rest right through. Its format is:
1166 * 0-1 msg_length - decoded by the record layer
1167 * 2 msg_type - s->init_msg points here
1169 * 5-6 cipher_spec_length
1170 * 7-8 session_id_length
1171 * 9-10 challenge_length
1175 if (!PACKET_get_1(pkt, &mt)
1176 || mt != SSL2_MT_CLIENT_HELLO) {
1178 * Should never happen. We should have tested this in the record
1179 * layer in order to have determined that this is a SSLv2 record
1180 * in the first place
1182 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, ERR_R_INTERNAL_ERROR);
1187 if (!PACKET_get_net_2(pkt, &clienthello.legacy_version)) {
1188 al = SSL_AD_DECODE_ERROR;
1189 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_TOO_SHORT);
1193 /* Parse the message and load client random. */
1194 if (clienthello.isv2) {
1196 * Handle an SSLv2 backwards compatible ClientHello
1197 * Note, this is only for SSLv3+ using the backward compatible format.
1198 * Real SSLv2 is not supported, and is rejected below.
1200 unsigned int ciphersuite_len, session_id_len, challenge_len;
1203 if (!PACKET_get_net_2(pkt, &ciphersuite_len)
1204 || !PACKET_get_net_2(pkt, &session_id_len)
1205 || !PACKET_get_net_2(pkt, &challenge_len)) {
1206 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO,
1207 SSL_R_RECORD_LENGTH_MISMATCH);
1208 al = SSL_AD_DECODE_ERROR;
1212 if (session_id_len > SSL_MAX_SSL_SESSION_ID_LENGTH) {
1213 al = SSL_AD_DECODE_ERROR;
1214 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
1218 if (!PACKET_get_sub_packet(pkt, &clienthello.ciphersuites,
1220 || !PACKET_copy_bytes(pkt, clienthello.session_id, session_id_len)
1221 || !PACKET_get_sub_packet(pkt, &challenge, challenge_len)
1222 /* No extensions. */
1223 || PACKET_remaining(pkt) != 0) {
1224 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO,
1225 SSL_R_RECORD_LENGTH_MISMATCH);
1226 al = SSL_AD_DECODE_ERROR;
1229 clienthello.session_id_len = session_id_len;
1231 /* Load the client random and compression list. We use SSL3_RANDOM_SIZE
1232 * here rather than sizeof(clienthello.random) because that is the limit
1233 * for SSLv3 and it is fixed. It won't change even if
1234 * sizeof(clienthello.random) does.
1236 challenge_len = challenge_len > SSL3_RANDOM_SIZE
1237 ? SSL3_RANDOM_SIZE : challenge_len;
1238 memset(clienthello.random, 0, SSL3_RANDOM_SIZE);
1239 if (!PACKET_copy_bytes(&challenge,
1240 clienthello.random + SSL3_RANDOM_SIZE -
1241 challenge_len, challenge_len)
1242 /* Advertise only null compression. */
1243 || !PACKET_buf_init(&compression, &null_compression, 1)) {
1244 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, ERR_R_INTERNAL_ERROR);
1245 al = SSL_AD_INTERNAL_ERROR;
1249 PACKET_null_init(&clienthello.extensions);
1251 /* Regular ClientHello. */
1252 if (!PACKET_copy_bytes(pkt, clienthello.random, SSL3_RANDOM_SIZE)
1253 || !PACKET_get_length_prefixed_1(pkt, &session_id)
1254 || !PACKET_copy_all(&session_id, clienthello.session_id,
1255 SSL_MAX_SSL_SESSION_ID_LENGTH,
1256 &clienthello.session_id_len)) {
1257 al = SSL_AD_DECODE_ERROR;
1258 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
1262 if (SSL_IS_DTLS(s)) {
1263 if (!PACKET_get_length_prefixed_1(pkt, &cookie)) {
1264 al = SSL_AD_DECODE_ERROR;
1265 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
1268 if (!PACKET_copy_all(&cookie, clienthello.dtls_cookie,
1269 DTLS1_COOKIE_LENGTH,
1270 &clienthello.dtls_cookie_len)) {
1271 al = SSL_AD_DECODE_ERROR;
1272 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
1276 * If we require cookies and this ClientHello doesn't contain one,
1277 * just return since we do not want to allocate any memory yet.
1278 * So check cookie length...
1280 if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) {
1281 if (clienthello.dtls_cookie_len == 0)
1286 if (!PACKET_get_length_prefixed_2(pkt, &clienthello.ciphersuites)) {
1287 al = SSL_AD_DECODE_ERROR;
1288 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
1292 if (!PACKET_get_length_prefixed_1(pkt, &compression)) {
1293 al = SSL_AD_DECODE_ERROR;
1294 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
1298 /* Could be empty. */
1299 if (PACKET_remaining(pkt) == 0) {
1300 PACKET_null_init(&clienthello.extensions);
1302 if (!PACKET_get_length_prefixed_2(pkt, &clienthello.extensions)) {
1303 al = SSL_AD_DECODE_ERROR;
1304 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
1310 if (!PACKET_copy_all(&compression, clienthello.compressions,
1311 MAX_COMPRESSIONS_SIZE,
1312 &clienthello.compressions_len)) {
1313 al = SSL_AD_DECODE_ERROR;
1314 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
1318 /* Preserve the raw extensions PACKET for later use */
1319 extensions = clienthello.extensions;
1320 if (!tls_collect_extensions(s, &extensions, EXT_CLIENT_HELLO,
1321 &clienthello.pre_proc_exts, &al)) {
1322 /* SSLerr already been called */
1326 /* Finished parsing the ClientHello, now we can start processing it */
1328 /* Set up the client_random */
1329 memcpy(s->s3->client_random, clienthello.random, SSL3_RANDOM_SIZE);
1331 /* Choose the version */
1333 if (clienthello.isv2) {
1334 if (clienthello.legacy_version == SSL2_VERSION
1335 || (clienthello.legacy_version & 0xff00)
1336 != (SSL3_VERSION_MAJOR << 8)) {
1338 * This is real SSLv2 or something complete unknown. We don't
1341 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_UNKNOWN_PROTOCOL);
1345 s->client_version = clienthello.legacy_version;
1348 * Do SSL/TLS version negotiation if applicable. For DTLS we just check
1349 * versions are potentially compatible. Version negotiation comes later.
1351 if (!SSL_IS_DTLS(s)) {
1352 protverr = ssl_choose_server_version(s, &clienthello);
1353 } else if (s->method->version != DTLS_ANY_VERSION &&
1354 DTLS_VERSION_LT((int)clienthello.legacy_version, s->version)) {
1355 protverr = SSL_R_VERSION_TOO_LOW;
1361 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, protverr);
1362 if ((!s->enc_write_ctx && !s->write_hash)) {
1363 /* like ssl3_get_record, send alert using remote version number */
1364 s->version = s->client_version = clienthello.legacy_version;
1366 al = SSL_AD_PROTOCOL_VERSION;
1370 if (SSL_IS_DTLS(s)) {
1371 /* Empty cookie was already handled above by returning early. */
1372 if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) {
1373 if (s->ctx->app_verify_cookie_cb != NULL) {
1374 if (s->ctx->app_verify_cookie_cb(s, clienthello.dtls_cookie,
1375 clienthello.dtls_cookie_len) == 0) {
1376 al = SSL_AD_HANDSHAKE_FAILURE;
1377 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO,
1378 SSL_R_COOKIE_MISMATCH);
1380 /* else cookie verification succeeded */
1382 /* default verification */
1383 } else if (s->d1->cookie_len != clienthello.dtls_cookie_len
1384 || memcmp(clienthello.dtls_cookie, s->d1->cookie,
1385 s->d1->cookie_len) != 0) {
1386 al = SSL_AD_HANDSHAKE_FAILURE;
1387 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_COOKIE_MISMATCH);
1390 s->d1->cookie_verified = 1;
1392 if (s->method->version == DTLS_ANY_VERSION) {
1393 protverr = ssl_choose_server_version(s, &clienthello);
1394 if (protverr != 0) {
1395 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, protverr);
1396 s->version = s->client_version;
1397 al = SSL_AD_PROTOCOL_VERSION;
1405 /* We need to do this before getting the session */
1406 if (!tls_parse_extension(s, TLSEXT_IDX_extended_master_secret,
1408 clienthello.pre_proc_exts, NULL, 0, &al)) {
1409 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_CLIENTHELLO_TLSEXT);
1414 * We don't allow resumption in a backwards compatible ClientHello.
1415 * TODO(openssl-team): in TLS1.1+, session_id MUST be empty.
1417 * Versions before 0.9.7 always allow clients to resume sessions in
1418 * renegotiation. 0.9.7 and later allow this by default, but optionally
1419 * ignore resumption requests with flag
1420 * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION (it's a new flag rather
1421 * than a change to default behavior so that applications relying on
1422 * this for security won't even compile against older library versions).
1423 * 1.0.1 and later also have a function SSL_renegotiate_abbreviated() to
1424 * request renegotiation but not a new session (s->new_session remains
1425 * unset): for servers, this essentially just means that the
1426 * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION setting will be
1429 if (clienthello.isv2 ||
1431 (s->options & SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION))) {
1432 if (!ssl_get_new_session(s, 1))
1435 i = ssl_get_prev_session(s, &clienthello);
1437 * Only resume if the session's version matches the negotiated
1439 * RFC 5246 does not provide much useful advice on resumption
1440 * with a different protocol version. It doesn't forbid it but
1441 * the sanity of such behaviour would be questionable.
1442 * In practice, clients do not accept a version mismatch and
1443 * will abort the handshake with an error.
1445 if (i == 1 && s->version == s->session->ssl_version) {
1446 /* previous session */
1448 } else if (i == -1) {
1452 if (!ssl_get_new_session(s, 1))
1457 if (ssl_bytes_to_cipher_list(s, &clienthello.ciphersuites, &ciphers,
1458 clienthello.isv2, &al) == NULL) {
1462 /* If it is a hit, check that the cipher is in the list */
1465 id = s->session->cipher->id;
1468 fprintf(stderr, "client sent %d ciphers\n", sk_SSL_CIPHER_num(ciphers));
1470 for (i = 0; i < sk_SSL_CIPHER_num(ciphers); i++) {
1471 c = sk_SSL_CIPHER_value(ciphers, i);
1473 fprintf(stderr, "client [%2d of %2d]:%s\n",
1474 i, sk_SSL_CIPHER_num(ciphers), SSL_CIPHER_get_name(c));
1483 * we need to have the cipher in the cipher list if we are asked
1486 al = SSL_AD_ILLEGAL_PARAMETER;
1487 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO,
1488 SSL_R_REQUIRED_CIPHER_MISSING);
1493 for (loop = 0; loop < clienthello.compressions_len; loop++) {
1494 if (clienthello.compressions[loop] == 0)
1498 if (loop >= clienthello.compressions_len) {
1500 al = SSL_AD_DECODE_ERROR;
1501 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_NO_COMPRESSION_SPECIFIED);
1505 #ifndef OPENSSL_NO_EC
1506 if (s->options & SSL_OP_SAFARI_ECDHE_ECDSA_BUG)
1507 ssl_check_for_safari(s, &clienthello);
1508 #endif /* !OPENSSL_NO_EC */
1510 /* TLS extensions */
1511 if (!tls_parse_all_extensions(s, EXT_CLIENT_HELLO,
1512 clienthello.pre_proc_exts, NULL, 0, &al)) {
1513 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_PARSE_TLSEXT);
1517 /* Check we've got a key_share for TLSv1.3 */
1518 if (SSL_IS_TLS13(s) && s->s3->peer_tmp == NULL && !s->hit) {
1519 /* No suitable share */
1520 /* TODO(TLS1.3): Send a HelloRetryRequest */
1521 al = SSL_AD_HANDSHAKE_FAILURE;
1522 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_NO_SUITABLE_KEY_SHARE);
1527 * Check if we want to use external pre-shared secret for this handshake
1528 * for not reused session only. We need to generate server_random before
1529 * calling tls_session_secret_cb in order to allow SessionTicket
1530 * processing to use it in key derivation.
1534 pos = s->s3->server_random;
1535 if (ssl_fill_hello_random(s, 1, pos, SSL3_RANDOM_SIZE) <= 0) {
1540 if (!s->hit && s->version >= TLS1_VERSION && s->ext.session_secret_cb) {
1541 const SSL_CIPHER *pref_cipher = NULL;
1543 * s->session->master_key_length is a size_t, but this is an int for
1544 * backwards compat reasons
1546 int master_key_length;
1548 master_key_length = sizeof(s->session->master_key);
1549 if (s->ext.session_secret_cb(s, s->session->master_key,
1550 &master_key_length, ciphers,
1552 s->ext.session_secret_cb_arg)
1553 && master_key_length > 0) {
1554 s->session->master_key_length = master_key_length;
1556 s->session->ciphers = ciphers;
1557 s->session->verify_result = X509_V_OK;
1561 /* check if some cipher was preferred by call back */
1563 pref_cipher ? pref_cipher : ssl3_choose_cipher(s,
1568 if (pref_cipher == NULL) {
1569 al = SSL_AD_HANDSHAKE_FAILURE;
1570 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_NO_SHARED_CIPHER);
1574 s->session->cipher = pref_cipher;
1575 sk_SSL_CIPHER_free(s->cipher_list);
1576 s->cipher_list = sk_SSL_CIPHER_dup(s->session->ciphers);
1577 sk_SSL_CIPHER_free(s->cipher_list_by_id);
1578 s->cipher_list_by_id = sk_SSL_CIPHER_dup(s->session->ciphers);
1583 * Worst case, we will use the NULL compression, but if we have other
1584 * options, we will now look for them. We have complen-1 compression
1585 * algorithms from the client, starting at q.
1587 s->s3->tmp.new_compression = NULL;
1588 #ifndef OPENSSL_NO_COMP
1589 /* This only happens if we have a cache hit */
1590 if (s->session->compress_meth != 0) {
1591 int m, comp_id = s->session->compress_meth;
1593 /* Perform sanity checks on resumed compression algorithm */
1594 /* Can't disable compression */
1595 if (!ssl_allow_compression(s)) {
1596 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO,
1597 SSL_R_INCONSISTENT_COMPRESSION);
1600 /* Look for resumed compression method */
1601 for (m = 0; m < sk_SSL_COMP_num(s->ctx->comp_methods); m++) {
1602 comp = sk_SSL_COMP_value(s->ctx->comp_methods, m);
1603 if (comp_id == comp->id) {
1604 s->s3->tmp.new_compression = comp;
1608 if (s->s3->tmp.new_compression == NULL) {
1609 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO,
1610 SSL_R_INVALID_COMPRESSION_ALGORITHM);
1613 /* Look for resumed method in compression list */
1614 for (k = 0; k < clienthello.compressions_len; k++) {
1615 if (clienthello.compressions[k] == comp_id)
1618 if (k >= clienthello.compressions_len) {
1619 al = SSL_AD_ILLEGAL_PARAMETER;
1620 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO,
1621 SSL_R_REQUIRED_COMPRESSION_ALGORITHM_MISSING);
1626 else if (ssl_allow_compression(s) && s->ctx->comp_methods) {
1627 /* See if we have a match */
1628 int m, nn, v, done = 0;
1631 nn = sk_SSL_COMP_num(s->ctx->comp_methods);
1632 for (m = 0; m < nn; m++) {
1633 comp = sk_SSL_COMP_value(s->ctx->comp_methods, m);
1635 for (o = 0; o < clienthello.compressions_len; o++) {
1636 if (v == clienthello.compressions[o]) {
1645 s->s3->tmp.new_compression = comp;
1651 * If compression is disabled we'd better not try to resume a session
1652 * using compression.
1654 if (s->session->compress_meth != 0) {
1655 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_INCONSISTENT_COMPRESSION);
1661 * Given s->session->ciphers and SSL_get_ciphers, we must pick a cipher
1665 #ifdef OPENSSL_NO_COMP
1666 s->session->compress_meth = 0;
1668 s->session->compress_meth = (comp == NULL) ? 0 : comp->id;
1670 sk_SSL_CIPHER_free(s->session->ciphers);
1671 s->session->ciphers = ciphers;
1672 if (ciphers == NULL) {
1673 al = SSL_AD_INTERNAL_ERROR;
1674 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, ERR_R_INTERNAL_ERROR);
1678 if (!tls1_set_server_sigalgs(s)) {
1679 SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_CLIENTHELLO_TLSEXT);
1684 sk_SSL_CIPHER_free(ciphers);
1685 OPENSSL_free(clienthello.pre_proc_exts);
1686 return MSG_PROCESS_CONTINUE_PROCESSING;
1688 ssl3_send_alert(s, SSL3_AL_FATAL, al);
1690 ossl_statem_set_error(s);
1692 sk_SSL_CIPHER_free(ciphers);
1693 OPENSSL_free(clienthello.pre_proc_exts);
1695 return MSG_PROCESS_ERROR;
1699 * Call the status request callback if needed. Upon success, returns 1.
1700 * Upon failure, returns 0 and sets |*al| to the appropriate fatal alert.
1702 static int tls_handle_status_request(SSL *s, int *al)
1704 s->ext.status_expected = 0;
1707 * If status request then ask callback what to do. Note: this must be
1708 * called after servername callbacks in case the certificate has changed,
1709 * and must be called after the cipher has been chosen because this may
1710 * influence which certificate is sent
1712 if (s->ext.status_type != TLSEXT_STATUSTYPE_nothing && s->ctx != NULL
1713 && s->ctx->ext.status_cb != NULL) {
1715 CERT_PKEY *certpkey = ssl_get_server_send_pkey(s);
1717 /* If no certificate can't return certificate status */
1718 if (certpkey != NULL) {
1720 * Set current certificate to one we will use so SSL_get_certificate
1721 * et al can pick it up.
1723 s->cert->key = certpkey;
1724 ret = s->ctx->ext.status_cb(s, s->ctx->ext.status_arg);
1726 /* We don't want to send a status request response */
1727 case SSL_TLSEXT_ERR_NOACK:
1728 s->ext.status_expected = 0;
1730 /* status request response should be sent */
1731 case SSL_TLSEXT_ERR_OK:
1732 if (s->ext.ocsp.resp)
1733 s->ext.status_expected = 1;
1735 /* something bad happened */
1736 case SSL_TLSEXT_ERR_ALERT_FATAL:
1738 *al = SSL_AD_INTERNAL_ERROR;
1747 WORK_STATE tls_post_process_client_hello(SSL *s, WORK_STATE wst)
1749 int al = SSL_AD_HANDSHAKE_FAILURE;
1750 const SSL_CIPHER *cipher;
1752 if (wst == WORK_MORE_A) {
1754 /* Let cert callback update server certificates if required */
1755 if (s->cert->cert_cb) {
1756 int rv = s->cert->cert_cb(s, s->cert->cert_cb_arg);
1758 al = SSL_AD_INTERNAL_ERROR;
1759 SSLerr(SSL_F_TLS_POST_PROCESS_CLIENT_HELLO,
1760 SSL_R_CERT_CB_ERROR);
1764 s->rwstate = SSL_X509_LOOKUP;
1767 s->rwstate = SSL_NOTHING;
1770 ssl3_choose_cipher(s, s->session->ciphers, SSL_get_ciphers(s));
1772 if (cipher == NULL) {
1773 SSLerr(SSL_F_TLS_POST_PROCESS_CLIENT_HELLO,
1774 SSL_R_NO_SHARED_CIPHER);
1777 s->s3->tmp.new_cipher = cipher;
1778 /* check whether we should disable session resumption */
1779 if (s->not_resumable_session_cb != NULL)
1780 s->session->not_resumable =
1781 s->not_resumable_session_cb(s, ((cipher->algorithm_mkey
1782 & (SSL_kDHE | SSL_kECDHE))
1784 if (s->session->not_resumable)
1785 /* do not send a session ticket */
1786 s->ext.ticket_expected = 0;
1788 /* Session-id reuse */
1789 s->s3->tmp.new_cipher = s->session->cipher;
1792 if (!(s->verify_mode & SSL_VERIFY_PEER)) {
1793 if (!ssl3_digest_cached_records(s, 0)) {
1794 al = SSL_AD_INTERNAL_ERROR;
1800 * we now have the following setup.
1802 * cipher_list - our preferred list of ciphers
1803 * ciphers - the clients preferred list of ciphers
1804 * compression - basically ignored right now
1805 * ssl version is set - sslv3
1806 * s->session - The ssl session has been setup.
1807 * s->hit - session reuse flag
1808 * s->s3->tmp.new_cipher- the new cipher to use.
1812 * Call status_request callback if needed. Has to be done after the
1813 * certificate callbacks etc above.
1815 if (!tls_handle_status_request(s, &al)) {
1816 SSLerr(SSL_F_TLS_POST_PROCESS_CLIENT_HELLO,
1817 SSL_R_CLIENTHELLO_TLSEXT);
1823 #ifndef OPENSSL_NO_SRP
1824 if (wst == WORK_MORE_B) {
1826 if ((ret = ssl_check_srp_ext_ClientHello(s, &al)) < 0) {
1828 * callback indicates further work to be done
1830 s->rwstate = SSL_X509_LOOKUP;
1833 if (ret != SSL_ERROR_NONE) {
1835 * This is not really an error but the only means to for
1836 * a client to detect whether srp is supported.
1838 if (al != TLS1_AD_UNKNOWN_PSK_IDENTITY)
1839 SSLerr(SSL_F_TLS_POST_PROCESS_CLIENT_HELLO,
1840 SSL_R_CLIENTHELLO_TLSEXT);
1842 SSLerr(SSL_F_TLS_POST_PROCESS_CLIENT_HELLO,
1843 SSL_R_PSK_IDENTITY_NOT_FOUND);
1850 return WORK_FINISHED_STOP;
1852 ssl3_send_alert(s, SSL3_AL_FATAL, al);
1853 ossl_statem_set_error(s);
1857 int tls_construct_server_hello(SSL *s, WPACKET *pkt)
1859 int compm, al = SSL_AD_INTERNAL_ERROR;
1863 /* TODO(TLS1.3): Remove the DRAFT conditional before release */
1864 version = SSL_IS_TLS13(s) ? TLS1_3_VERSION_DRAFT : s->version;
1865 if (!WPACKET_put_bytes_u16(pkt, version)
1867 * Random stuff. Filling of the server_random takes place in
1868 * tls_process_client_hello()
1870 || !WPACKET_memcpy(pkt, s->s3->server_random, SSL3_RANDOM_SIZE)) {
1871 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
1876 * There are several cases for the session ID to send
1877 * back in the server hello:
1878 * - For session reuse from the session cache,
1879 * we send back the old session ID.
1880 * - If stateless session reuse (using a session ticket)
1881 * is successful, we send back the client's "session ID"
1882 * (which doesn't actually identify the session).
1883 * - If it is a new session, we send back the new
1885 * - However, if we want the new session to be single-use,
1886 * we send back a 0-length session ID.
1887 * s->hit is non-zero in either case of session reuse,
1888 * so the following won't overwrite an ID that we're supposed
1891 if (s->session->not_resumable ||
1892 (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER)
1894 s->session->session_id_length = 0;
1896 sl = s->session->session_id_length;
1897 if (sl > sizeof(s->session->session_id)) {
1898 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
1902 /* set up the compression method */
1903 #ifdef OPENSSL_NO_COMP
1906 if (s->s3->tmp.new_compression == NULL)
1909 compm = s->s3->tmp.new_compression->id;
1912 if ((!SSL_IS_TLS13(s)
1913 && !WPACKET_sub_memcpy_u8(pkt, s->session->session_id, sl))
1914 || !s->method->put_cipher_by_char(s->s3->tmp.new_cipher, pkt, &len)
1915 || (!SSL_IS_TLS13(s)
1916 && !WPACKET_put_bytes_u8(pkt, compm))
1917 || !tls_construct_extensions(s, pkt,
1919 ? EXT_TLS1_3_SERVER_HELLO
1920 : EXT_TLS1_2_SERVER_HELLO,
1922 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
1928 ssl3_send_alert(s, SSL3_AL_FATAL, al);
1932 int tls_construct_server_done(SSL *s, WPACKET *pkt)
1934 if (!s->s3->tmp.cert_request) {
1935 if (!ssl3_digest_cached_records(s, 0)) {
1936 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
1943 int tls_construct_server_key_exchange(SSL *s, WPACKET *pkt)
1945 #ifndef OPENSSL_NO_DH
1946 EVP_PKEY *pkdh = NULL;
1948 #ifndef OPENSSL_NO_EC
1949 unsigned char *encodedPoint = NULL;
1950 size_t encodedlen = 0;
1954 const EVP_MD *md = NULL;
1955 int al = SSL_AD_INTERNAL_ERROR, i;
1958 EVP_MD_CTX *md_ctx = EVP_MD_CTX_new();
1959 EVP_PKEY_CTX *pctx = NULL;
1960 size_t paramlen, paramoffset;
1962 if (!WPACKET_get_total_written(pkt, ¶moffset)) {
1963 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
1967 if (md_ctx == NULL) {
1968 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_MALLOC_FAILURE);
1972 type = s->s3->tmp.new_cipher->algorithm_mkey;
1974 r[0] = r[1] = r[2] = r[3] = NULL;
1975 #ifndef OPENSSL_NO_PSK
1976 /* Plain PSK or RSAPSK nothing to do */
1977 if (type & (SSL_kPSK | SSL_kRSAPSK)) {
1979 #endif /* !OPENSSL_NO_PSK */
1980 #ifndef OPENSSL_NO_DH
1981 if (type & (SSL_kDHE | SSL_kDHEPSK)) {
1982 CERT *cert = s->cert;
1984 EVP_PKEY *pkdhp = NULL;
1987 if (s->cert->dh_tmp_auto) {
1988 DH *dhp = ssl_get_auto_dh(s);
1989 pkdh = EVP_PKEY_new();
1990 if (pkdh == NULL || dhp == NULL) {
1992 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
1993 ERR_R_INTERNAL_ERROR);
1996 EVP_PKEY_assign_DH(pkdh, dhp);
1999 pkdhp = cert->dh_tmp;
2001 if ((pkdhp == NULL) && (s->cert->dh_tmp_cb != NULL)) {
2002 DH *dhp = s->cert->dh_tmp_cb(s, 0, 1024);
2003 pkdh = ssl_dh_to_pkey(dhp);
2005 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2006 ERR_R_INTERNAL_ERROR);
2011 if (pkdhp == NULL) {
2012 al = SSL_AD_HANDSHAKE_FAILURE;
2013 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2014 SSL_R_MISSING_TMP_DH_KEY);
2017 if (!ssl_security(s, SSL_SECOP_TMP_DH,
2018 EVP_PKEY_security_bits(pkdhp), 0, pkdhp)) {
2019 al = SSL_AD_HANDSHAKE_FAILURE;
2020 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2021 SSL_R_DH_KEY_TOO_SMALL);
2024 if (s->s3->tmp.pkey != NULL) {
2025 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2026 ERR_R_INTERNAL_ERROR);
2030 s->s3->tmp.pkey = ssl_generate_pkey(pkdhp);
2032 if (s->s3->tmp.pkey == NULL) {
2033 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_EVP_LIB);
2037 dh = EVP_PKEY_get0_DH(s->s3->tmp.pkey);
2039 EVP_PKEY_free(pkdh);
2042 DH_get0_pqg(dh, &r[0], NULL, &r[1]);
2043 DH_get0_key(dh, &r[2], NULL);
2046 #ifndef OPENSSL_NO_EC
2047 if (type & (SSL_kECDHE | SSL_kECDHEPSK)) {
2050 if (s->s3->tmp.pkey != NULL) {
2051 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2052 ERR_R_INTERNAL_ERROR);
2056 /* Get NID of appropriate shared curve */
2057 nid = tls1_shared_group(s, -2);
2058 curve_id = tls1_ec_nid2curve_id(nid);
2059 if (curve_id == 0) {
2060 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2061 SSL_R_UNSUPPORTED_ELLIPTIC_CURVE);
2064 s->s3->tmp.pkey = ssl_generate_pkey_curve(curve_id);
2065 /* Generate a new key for this curve */
2066 if (s->s3->tmp.pkey == NULL) {
2067 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_EVP_LIB);
2071 /* Encode the public key. */
2072 encodedlen = EVP_PKEY_get1_tls_encodedpoint(s->s3->tmp.pkey,
2074 if (encodedlen == 0) {
2075 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE, ERR_R_EC_LIB);
2080 * We'll generate the serverKeyExchange message explicitly so we
2081 * can set these to NULLs
2088 #endif /* !OPENSSL_NO_EC */
2089 #ifndef OPENSSL_NO_SRP
2090 if (type & SSL_kSRP) {
2091 if ((s->srp_ctx.N == NULL) ||
2092 (s->srp_ctx.g == NULL) ||
2093 (s->srp_ctx.s == NULL) || (s->srp_ctx.B == NULL)) {
2094 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2095 SSL_R_MISSING_SRP_PARAM);
2098 r[0] = s->srp_ctx.N;
2099 r[1] = s->srp_ctx.g;
2100 r[2] = s->srp_ctx.s;
2101 r[3] = s->srp_ctx.B;
2105 al = SSL_AD_HANDSHAKE_FAILURE;
2106 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2107 SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE);
2111 if (!(s->s3->tmp.new_cipher->algorithm_auth & (SSL_aNULL | SSL_aSRP))
2112 && !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_PSK)) {
2113 if ((pkey = ssl_get_sign_pkey(s, s->s3->tmp.new_cipher, &md))
2115 al = SSL_AD_DECODE_ERROR;
2122 #ifndef OPENSSL_NO_PSK
2123 if (type & SSL_PSK) {
2124 size_t len = (s->cert->psk_identity_hint == NULL)
2125 ? 0 : strlen(s->cert->psk_identity_hint);
2128 * It should not happen that len > PSK_MAX_IDENTITY_LEN - we already
2129 * checked this when we set the identity hint - but just in case
2131 if (len > PSK_MAX_IDENTITY_LEN
2132 || !WPACKET_sub_memcpy_u16(pkt, s->cert->psk_identity_hint,
2134 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2135 ERR_R_INTERNAL_ERROR);
2141 for (i = 0; i < 4 && r[i] != NULL; i++) {
2142 unsigned char *binval;
2145 #ifndef OPENSSL_NO_SRP
2146 if ((i == 2) && (type & SSL_kSRP)) {
2147 res = WPACKET_start_sub_packet_u8(pkt);
2150 res = WPACKET_start_sub_packet_u16(pkt);
2153 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2154 ERR_R_INTERNAL_ERROR);
2158 #ifndef OPENSSL_NO_DH
2160 * for interoperability with some versions of the Microsoft TLS
2161 * stack, we need to zero pad the DHE pub key to the same length
2164 if ((i == 2) && (type & (SSL_kDHE | SSL_kDHEPSK))) {
2165 size_t len = BN_num_bytes(r[0]) - BN_num_bytes(r[2]);
2168 if (!WPACKET_allocate_bytes(pkt, len, &binval)) {
2169 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2170 ERR_R_INTERNAL_ERROR);
2173 memset(binval, 0, len);
2177 if (!WPACKET_allocate_bytes(pkt, BN_num_bytes(r[i]), &binval)
2178 || !WPACKET_close(pkt)) {
2179 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2180 ERR_R_INTERNAL_ERROR);
2184 BN_bn2bin(r[i], binval);
2187 #ifndef OPENSSL_NO_EC
2188 if (type & (SSL_kECDHE | SSL_kECDHEPSK)) {
2190 * We only support named (not generic) curves. In this situation, the
2191 * ServerKeyExchange message has: [1 byte CurveType], [2 byte CurveName]
2192 * [1 byte length of encoded point], followed by the actual encoded
2195 if (!WPACKET_put_bytes_u8(pkt, NAMED_CURVE_TYPE)
2196 || !WPACKET_put_bytes_u8(pkt, 0)
2197 || !WPACKET_put_bytes_u8(pkt, curve_id)
2198 || !WPACKET_sub_memcpy_u8(pkt, encodedPoint, encodedlen)) {
2199 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2200 ERR_R_INTERNAL_ERROR);
2203 OPENSSL_free(encodedPoint);
2204 encodedPoint = NULL;
2211 * n is the length of the params, they start at &(d[4]) and p
2212 * points to the space at the end.
2215 unsigned char *sigbytes1, *sigbytes2;
2219 /* Get length of the parameters we have written above */
2220 if (!WPACKET_get_length(pkt, ¶mlen)) {
2221 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2222 ERR_R_INTERNAL_ERROR);
2225 /* send signature algorithm */
2226 if (SSL_USE_SIGALGS(s)) {
2227 if (!tls12_get_sigandhash(s, pkt, pkey, md, &ispss)) {
2228 /* Should never happen */
2229 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2230 ERR_R_INTERNAL_ERROR);
2235 fprintf(stderr, "Using hash %s\n", EVP_MD_name(md));
2238 * Create the signature. We don't know the actual length of the sig
2239 * until after we've created it, so we reserve enough bytes for it
2240 * up front, and then properly allocate them in the WPACKET
2243 siglen = EVP_PKEY_size(pkey);
2244 if (!WPACKET_sub_reserve_bytes_u16(pkt, siglen, &sigbytes1)
2245 || EVP_DigestSignInit(md_ctx, &pctx, md, NULL, pkey) <= 0) {
2246 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2247 ERR_R_INTERNAL_ERROR);
2251 if (EVP_PKEY_CTX_set_rsa_padding(pctx,
2252 RSA_PKCS1_PSS_PADDING) <= 0
2253 /* -1 here means set saltlen to the digest len */
2254 || EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, -1) <= 0) {
2255 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2260 if (EVP_DigestSignUpdate(md_ctx, &(s->s3->client_random[0]),
2261 SSL3_RANDOM_SIZE) <= 0
2262 || EVP_DigestSignUpdate(md_ctx, &(s->s3->server_random[0]),
2263 SSL3_RANDOM_SIZE) <= 0
2264 || EVP_DigestSignUpdate(md_ctx,
2265 s->init_buf->data + paramoffset,
2267 || EVP_DigestSignFinal(md_ctx, sigbytes1, &siglen) <= 0
2268 || !WPACKET_sub_allocate_bytes_u16(pkt, siglen, &sigbytes2)
2269 || sigbytes1 != sigbytes2) {
2270 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2271 ERR_R_INTERNAL_ERROR);
2275 /* Is this error check actually needed? */
2276 al = SSL_AD_HANDSHAKE_FAILURE;
2277 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE,
2278 SSL_R_UNKNOWN_PKEY_TYPE);
2283 EVP_MD_CTX_free(md_ctx);
2286 ssl3_send_alert(s, SSL3_AL_FATAL, al);
2288 #ifndef OPENSSL_NO_DH
2289 EVP_PKEY_free(pkdh);
2291 #ifndef OPENSSL_NO_EC
2292 OPENSSL_free(encodedPoint);
2294 EVP_MD_CTX_free(md_ctx);
2298 int tls_construct_certificate_request(SSL *s, WPACKET *pkt)
2301 STACK_OF(X509_NAME) *sk = NULL;
2303 /* get the list of acceptable cert types */
2304 if (!WPACKET_start_sub_packet_u8(pkt)
2305 || !ssl3_get_req_cert_type(s, pkt)
2306 || !WPACKET_close(pkt)) {
2307 SSLerr(SSL_F_TLS_CONSTRUCT_CERTIFICATE_REQUEST, ERR_R_INTERNAL_ERROR);
2311 if (SSL_USE_SIGALGS(s)) {
2312 const unsigned int *psigs;
2313 size_t nl = tls12_get_psigalgs(s, &psigs);
2315 if (!WPACKET_start_sub_packet_u16(pkt)
2316 || !tls12_copy_sigalgs(s, pkt, psigs, nl)
2317 || !WPACKET_close(pkt)) {
2318 SSLerr(SSL_F_TLS_CONSTRUCT_CERTIFICATE_REQUEST,
2319 ERR_R_INTERNAL_ERROR);
2324 /* Start sub-packet for client CA list */
2325 if (!WPACKET_start_sub_packet_u16(pkt)) {
2326 SSLerr(SSL_F_TLS_CONSTRUCT_CERTIFICATE_REQUEST, ERR_R_INTERNAL_ERROR);
2330 sk = SSL_get_client_CA_list(s);
2332 for (i = 0; i < sk_X509_NAME_num(sk); i++) {
2333 unsigned char *namebytes;
2334 X509_NAME *name = sk_X509_NAME_value(sk, i);
2338 || (namelen = i2d_X509_NAME(name, NULL)) < 0
2339 || !WPACKET_sub_allocate_bytes_u16(pkt, namelen,
2341 || i2d_X509_NAME(name, &namebytes) != namelen) {
2342 SSLerr(SSL_F_TLS_CONSTRUCT_CERTIFICATE_REQUEST,
2343 ERR_R_INTERNAL_ERROR);
2348 /* else no CA names */
2350 if (!WPACKET_close(pkt)) {
2351 SSLerr(SSL_F_TLS_CONSTRUCT_CERTIFICATE_REQUEST, ERR_R_INTERNAL_ERROR);
2355 s->s3->tmp.cert_request = 1;
2359 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
2363 static int tls_process_cke_psk_preamble(SSL *s, PACKET *pkt, int *al)
2365 #ifndef OPENSSL_NO_PSK
2366 unsigned char psk[PSK_MAX_PSK_LEN];
2368 PACKET psk_identity;
2370 if (!PACKET_get_length_prefixed_2(pkt, &psk_identity)) {
2371 *al = SSL_AD_DECODE_ERROR;
2372 SSLerr(SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE, SSL_R_LENGTH_MISMATCH);
2375 if (PACKET_remaining(&psk_identity) > PSK_MAX_IDENTITY_LEN) {
2376 *al = SSL_AD_DECODE_ERROR;
2377 SSLerr(SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE, SSL_R_DATA_LENGTH_TOO_LONG);
2380 if (s->psk_server_callback == NULL) {
2381 *al = SSL_AD_INTERNAL_ERROR;
2382 SSLerr(SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE, SSL_R_PSK_NO_SERVER_CB);
2386 if (!PACKET_strndup(&psk_identity, &s->session->psk_identity)) {
2387 *al = SSL_AD_INTERNAL_ERROR;
2388 SSLerr(SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE, ERR_R_INTERNAL_ERROR);
2392 psklen = s->psk_server_callback(s, s->session->psk_identity,
2395 if (psklen > PSK_MAX_PSK_LEN) {
2396 *al = SSL_AD_INTERNAL_ERROR;
2397 SSLerr(SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE, ERR_R_INTERNAL_ERROR);
2399 } else if (psklen == 0) {
2401 * PSK related to the given identity not found
2403 *al = SSL_AD_UNKNOWN_PSK_IDENTITY;
2404 SSLerr(SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE,
2405 SSL_R_PSK_IDENTITY_NOT_FOUND);
2409 OPENSSL_free(s->s3->tmp.psk);
2410 s->s3->tmp.psk = OPENSSL_memdup(psk, psklen);
2411 OPENSSL_cleanse(psk, psklen);
2413 if (s->s3->tmp.psk == NULL) {
2414 *al = SSL_AD_INTERNAL_ERROR;
2415 SSLerr(SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE, ERR_R_MALLOC_FAILURE);
2419 s->s3->tmp.psklen = psklen;
2423 /* Should never happen */
2424 *al = SSL_AD_INTERNAL_ERROR;
2425 SSLerr(SSL_F_TLS_PROCESS_CKE_PSK_PREAMBLE, ERR_R_INTERNAL_ERROR);
2430 static int tls_process_cke_rsa(SSL *s, PACKET *pkt, int *al)
2432 #ifndef OPENSSL_NO_RSA
2433 unsigned char rand_premaster_secret[SSL_MAX_MASTER_KEY_LENGTH];
2435 unsigned char decrypt_good, version_good;
2436 size_t j, padding_len;
2437 PACKET enc_premaster;
2439 unsigned char *rsa_decrypt = NULL;
2442 rsa = EVP_PKEY_get0_RSA(s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey);
2444 *al = SSL_AD_HANDSHAKE_FAILURE;
2445 SSLerr(SSL_F_TLS_PROCESS_CKE_RSA, SSL_R_MISSING_RSA_CERTIFICATE);
2449 /* SSLv3 and pre-standard DTLS omit the length bytes. */
2450 if (s->version == SSL3_VERSION || s->version == DTLS1_BAD_VER) {
2451 enc_premaster = *pkt;
2453 if (!PACKET_get_length_prefixed_2(pkt, &enc_premaster)
2454 || PACKET_remaining(pkt) != 0) {
2455 *al = SSL_AD_DECODE_ERROR;
2456 SSLerr(SSL_F_TLS_PROCESS_CKE_RSA, SSL_R_LENGTH_MISMATCH);
2462 * We want to be sure that the plaintext buffer size makes it safe to
2463 * iterate over the entire size of a premaster secret
2464 * (SSL_MAX_MASTER_KEY_LENGTH). Reject overly short RSA keys because
2465 * their ciphertext cannot accommodate a premaster secret anyway.
2467 if (RSA_size(rsa) < SSL_MAX_MASTER_KEY_LENGTH) {
2468 *al = SSL_AD_INTERNAL_ERROR;
2469 SSLerr(SSL_F_TLS_PROCESS_CKE_RSA, RSA_R_KEY_SIZE_TOO_SMALL);
2473 rsa_decrypt = OPENSSL_malloc(RSA_size(rsa));
2474 if (rsa_decrypt == NULL) {
2475 *al = SSL_AD_INTERNAL_ERROR;
2476 SSLerr(SSL_F_TLS_PROCESS_CKE_RSA, ERR_R_MALLOC_FAILURE);
2481 * We must not leak whether a decryption failure occurs because of
2482 * Bleichenbacher's attack on PKCS #1 v1.5 RSA padding (see RFC 2246,
2483 * section 7.4.7.1). The code follows that advice of the TLS RFC and
2484 * generates a random premaster secret for the case that the decrypt
2485 * fails. See https://tools.ietf.org/html/rfc5246#section-7.4.7.1
2488 if (RAND_bytes(rand_premaster_secret, sizeof(rand_premaster_secret)) <= 0)
2492 * Decrypt with no padding. PKCS#1 padding will be removed as part of
2493 * the timing-sensitive code below.
2495 /* TODO(size_t): Convert this function */
2496 decrypt_len = (int)RSA_private_decrypt((int)PACKET_remaining(&enc_premaster),
2497 PACKET_data(&enc_premaster),
2498 rsa_decrypt, rsa, RSA_NO_PADDING);
2499 if (decrypt_len < 0)
2502 /* Check the padding. See RFC 3447, section 7.2.2. */
2505 * The smallest padded premaster is 11 bytes of overhead. Small keys
2506 * are publicly invalid, so this may return immediately. This ensures
2507 * PS is at least 8 bytes.
2509 if (decrypt_len < 11 + SSL_MAX_MASTER_KEY_LENGTH) {
2510 *al = SSL_AD_DECRYPT_ERROR;
2511 SSLerr(SSL_F_TLS_PROCESS_CKE_RSA, SSL_R_DECRYPTION_FAILED);
2515 padding_len = decrypt_len - SSL_MAX_MASTER_KEY_LENGTH;
2516 decrypt_good = constant_time_eq_int_8(rsa_decrypt[0], 0) &
2517 constant_time_eq_int_8(rsa_decrypt[1], 2);
2518 for (j = 2; j < padding_len - 1; j++) {
2519 decrypt_good &= ~constant_time_is_zero_8(rsa_decrypt[j]);
2521 decrypt_good &= constant_time_is_zero_8(rsa_decrypt[padding_len - 1]);
2524 * If the version in the decrypted pre-master secret is correct then
2525 * version_good will be 0xff, otherwise it'll be zero. The
2526 * Klima-Pokorny-Rosa extension of Bleichenbacher's attack
2527 * (http://eprint.iacr.org/2003/052/) exploits the version number
2528 * check as a "bad version oracle". Thus version checks are done in
2529 * constant time and are treated like any other decryption error.
2532 constant_time_eq_8(rsa_decrypt[padding_len],
2533 (unsigned)(s->client_version >> 8));
2535 constant_time_eq_8(rsa_decrypt[padding_len + 1],
2536 (unsigned)(s->client_version & 0xff));
2539 * The premaster secret must contain the same version number as the
2540 * ClientHello to detect version rollback attacks (strangely, the
2541 * protocol does not offer such protection for DH ciphersuites).
2542 * However, buggy clients exist that send the negotiated protocol
2543 * version instead if the server does not support the requested
2544 * protocol version. If SSL_OP_TLS_ROLLBACK_BUG is set, tolerate such
2547 if (s->options & SSL_OP_TLS_ROLLBACK_BUG) {
2548 unsigned char workaround_good;
2549 workaround_good = constant_time_eq_8(rsa_decrypt[padding_len],
2550 (unsigned)(s->version >> 8));
2552 constant_time_eq_8(rsa_decrypt[padding_len + 1],
2553 (unsigned)(s->version & 0xff));
2554 version_good |= workaround_good;
2558 * Both decryption and version must be good for decrypt_good to
2559 * remain non-zero (0xff).
2561 decrypt_good &= version_good;
2564 * Now copy rand_premaster_secret over from p using
2565 * decrypt_good_mask. If decryption failed, then p does not
2566 * contain valid plaintext, however, a check above guarantees
2567 * it is still sufficiently large to read from.
2569 for (j = 0; j < sizeof(rand_premaster_secret); j++) {
2570 rsa_decrypt[padding_len + j] =
2571 constant_time_select_8(decrypt_good,
2572 rsa_decrypt[padding_len + j],
2573 rand_premaster_secret[j]);
2576 if (!ssl_generate_master_secret(s, rsa_decrypt + padding_len,
2577 sizeof(rand_premaster_secret), 0)) {
2578 *al = SSL_AD_INTERNAL_ERROR;
2579 SSLerr(SSL_F_TLS_PROCESS_CKE_RSA, ERR_R_INTERNAL_ERROR);
2585 OPENSSL_free(rsa_decrypt);
2588 /* Should never happen */
2589 *al = SSL_AD_INTERNAL_ERROR;
2590 SSLerr(SSL_F_TLS_PROCESS_CKE_RSA, ERR_R_INTERNAL_ERROR);
2595 static int tls_process_cke_dhe(SSL *s, PACKET *pkt, int *al)
2597 #ifndef OPENSSL_NO_DH
2598 EVP_PKEY *skey = NULL;
2602 const unsigned char *data;
2603 EVP_PKEY *ckey = NULL;
2606 if (!PACKET_get_net_2(pkt, &i) || PACKET_remaining(pkt) != i) {
2607 *al = SSL_AD_HANDSHAKE_FAILURE;
2608 SSLerr(SSL_F_TLS_PROCESS_CKE_DHE,
2609 SSL_R_DH_PUBLIC_VALUE_LENGTH_IS_WRONG);
2612 skey = s->s3->tmp.pkey;
2614 *al = SSL_AD_HANDSHAKE_FAILURE;
2615 SSLerr(SSL_F_TLS_PROCESS_CKE_DHE, SSL_R_MISSING_TMP_DH_KEY);
2619 if (PACKET_remaining(pkt) == 0L) {
2620 *al = SSL_AD_HANDSHAKE_FAILURE;
2621 SSLerr(SSL_F_TLS_PROCESS_CKE_DHE, SSL_R_MISSING_TMP_DH_KEY);
2624 if (!PACKET_get_bytes(pkt, &data, i)) {
2625 /* We already checked we have enough data */
2626 *al = SSL_AD_INTERNAL_ERROR;
2627 SSLerr(SSL_F_TLS_PROCESS_CKE_DHE, ERR_R_INTERNAL_ERROR);
2630 ckey = EVP_PKEY_new();
2631 if (ckey == NULL || EVP_PKEY_copy_parameters(ckey, skey) == 0) {
2632 SSLerr(SSL_F_TLS_PROCESS_CKE_DHE, SSL_R_BN_LIB);
2635 cdh = EVP_PKEY_get0_DH(ckey);
2636 pub_key = BN_bin2bn(data, i, NULL);
2638 if (pub_key == NULL || !DH_set0_key(cdh, pub_key, NULL)) {
2639 SSLerr(SSL_F_TLS_PROCESS_CKE_DHE, ERR_R_INTERNAL_ERROR);
2640 if (pub_key != NULL)
2645 if (ssl_derive(s, skey, ckey, 1) == 0) {
2646 *al = SSL_AD_INTERNAL_ERROR;
2647 SSLerr(SSL_F_TLS_PROCESS_CKE_DHE, ERR_R_INTERNAL_ERROR);
2652 EVP_PKEY_free(s->s3->tmp.pkey);
2653 s->s3->tmp.pkey = NULL;
2655 EVP_PKEY_free(ckey);
2658 /* Should never happen */
2659 *al = SSL_AD_INTERNAL_ERROR;
2660 SSLerr(SSL_F_TLS_PROCESS_CKE_DHE, ERR_R_INTERNAL_ERROR);
2665 static int tls_process_cke_ecdhe(SSL *s, PACKET *pkt, int *al)
2667 #ifndef OPENSSL_NO_EC
2668 EVP_PKEY *skey = s->s3->tmp.pkey;
2669 EVP_PKEY *ckey = NULL;
2672 if (PACKET_remaining(pkt) == 0L) {
2673 /* We don't support ECDH client auth */
2674 *al = SSL_AD_HANDSHAKE_FAILURE;
2675 SSLerr(SSL_F_TLS_PROCESS_CKE_ECDHE, SSL_R_MISSING_TMP_ECDH_KEY);
2679 const unsigned char *data;
2682 * Get client's public key from encoded point in the
2683 * ClientKeyExchange message.
2686 /* Get encoded point length */
2687 if (!PACKET_get_1(pkt, &i) || !PACKET_get_bytes(pkt, &data, i)
2688 || PACKET_remaining(pkt) != 0) {
2689 *al = SSL_AD_DECODE_ERROR;
2690 SSLerr(SSL_F_TLS_PROCESS_CKE_ECDHE, SSL_R_LENGTH_MISMATCH);
2693 ckey = EVP_PKEY_new();
2694 if (ckey == NULL || EVP_PKEY_copy_parameters(ckey, skey) <= 0) {
2695 SSLerr(SSL_F_TLS_PROCESS_CKE_ECDHE, ERR_R_EVP_LIB);
2698 if (EVP_PKEY_set1_tls_encodedpoint(ckey, data, i) == 0) {
2699 *al = SSL_AD_HANDSHAKE_FAILURE;
2700 SSLerr(SSL_F_TLS_PROCESS_CKE_ECDHE, ERR_R_EC_LIB);
2705 if (ssl_derive(s, skey, ckey, 1) == 0) {
2706 *al = SSL_AD_INTERNAL_ERROR;
2707 SSLerr(SSL_F_TLS_PROCESS_CKE_ECDHE, ERR_R_INTERNAL_ERROR);
2712 EVP_PKEY_free(s->s3->tmp.pkey);
2713 s->s3->tmp.pkey = NULL;
2715 EVP_PKEY_free(ckey);
2719 /* Should never happen */
2720 *al = SSL_AD_INTERNAL_ERROR;
2721 SSLerr(SSL_F_TLS_PROCESS_CKE_ECDHE, ERR_R_INTERNAL_ERROR);
2726 static int tls_process_cke_srp(SSL *s, PACKET *pkt, int *al)
2728 #ifndef OPENSSL_NO_SRP
2730 const unsigned char *data;
2732 if (!PACKET_get_net_2(pkt, &i)
2733 || !PACKET_get_bytes(pkt, &data, i)) {
2734 *al = SSL_AD_DECODE_ERROR;
2735 SSLerr(SSL_F_TLS_PROCESS_CKE_SRP, SSL_R_BAD_SRP_A_LENGTH);
2738 if ((s->srp_ctx.A = BN_bin2bn(data, i, NULL)) == NULL) {
2739 SSLerr(SSL_F_TLS_PROCESS_CKE_SRP, ERR_R_BN_LIB);
2742 if (BN_ucmp(s->srp_ctx.A, s->srp_ctx.N) >= 0 || BN_is_zero(s->srp_ctx.A)) {
2743 *al = SSL_AD_ILLEGAL_PARAMETER;
2744 SSLerr(SSL_F_TLS_PROCESS_CKE_SRP, SSL_R_BAD_SRP_PARAMETERS);
2747 OPENSSL_free(s->session->srp_username);
2748 s->session->srp_username = OPENSSL_strdup(s->srp_ctx.login);
2749 if (s->session->srp_username == NULL) {
2750 SSLerr(SSL_F_TLS_PROCESS_CKE_SRP, ERR_R_MALLOC_FAILURE);
2754 if (!srp_generate_server_master_secret(s)) {
2755 SSLerr(SSL_F_TLS_PROCESS_CKE_SRP, ERR_R_INTERNAL_ERROR);
2761 /* Should never happen */
2762 *al = SSL_AD_INTERNAL_ERROR;
2763 SSLerr(SSL_F_TLS_PROCESS_CKE_SRP, ERR_R_INTERNAL_ERROR);
2768 static int tls_process_cke_gost(SSL *s, PACKET *pkt, int *al)
2770 #ifndef OPENSSL_NO_GOST
2771 EVP_PKEY_CTX *pkey_ctx;
2772 EVP_PKEY *client_pub_pkey = NULL, *pk = NULL;
2773 unsigned char premaster_secret[32];
2774 const unsigned char *start;
2775 size_t outlen = 32, inlen;
2776 unsigned long alg_a;
2779 size_t sess_key_len;
2780 const unsigned char *data;
2783 /* Get our certificate private key */
2784 alg_a = s->s3->tmp.new_cipher->algorithm_auth;
2785 if (alg_a & SSL_aGOST12) {
2787 * New GOST ciphersuites have SSL_aGOST01 bit too
2789 pk = s->cert->pkeys[SSL_PKEY_GOST12_512].privatekey;
2791 pk = s->cert->pkeys[SSL_PKEY_GOST12_256].privatekey;
2794 pk = s->cert->pkeys[SSL_PKEY_GOST01].privatekey;
2796 } else if (alg_a & SSL_aGOST01) {
2797 pk = s->cert->pkeys[SSL_PKEY_GOST01].privatekey;
2800 pkey_ctx = EVP_PKEY_CTX_new(pk, NULL);
2801 if (pkey_ctx == NULL) {
2802 *al = SSL_AD_INTERNAL_ERROR;
2803 SSLerr(SSL_F_TLS_PROCESS_CKE_GOST, ERR_R_MALLOC_FAILURE);
2806 if (EVP_PKEY_decrypt_init(pkey_ctx) <= 0) {
2807 *al = SSL_AD_INTERNAL_ERROR;
2808 SSLerr(SSL_F_TLS_PROCESS_CKE_GOST, ERR_R_INTERNAL_ERROR);
2812 * If client certificate is present and is of the same type, maybe
2813 * use it for key exchange. Don't mind errors from
2814 * EVP_PKEY_derive_set_peer, because it is completely valid to use a
2815 * client certificate for authorization only.
2817 client_pub_pkey = X509_get0_pubkey(s->session->peer);
2818 if (client_pub_pkey) {
2819 if (EVP_PKEY_derive_set_peer(pkey_ctx, client_pub_pkey) <= 0)
2822 /* Decrypt session key */
2823 sess_key_len = PACKET_remaining(pkt);
2824 if (!PACKET_get_bytes(pkt, &data, sess_key_len)) {
2825 *al = SSL_AD_INTERNAL_ERROR;
2826 SSLerr(SSL_F_TLS_PROCESS_CKE_GOST, ERR_R_INTERNAL_ERROR);
2829 /* TODO(size_t): Convert this function */
2830 if (ASN1_get_object((const unsigned char **)&data, &Tlen, &Ttag,
2831 &Tclass, (long)sess_key_len) != V_ASN1_CONSTRUCTED
2832 || Ttag != V_ASN1_SEQUENCE || Tclass != V_ASN1_UNIVERSAL) {
2833 *al = SSL_AD_DECODE_ERROR;
2834 SSLerr(SSL_F_TLS_PROCESS_CKE_GOST, SSL_R_DECRYPTION_FAILED);
2839 if (EVP_PKEY_decrypt
2840 (pkey_ctx, premaster_secret, &outlen, start, inlen) <= 0) {
2841 *al = SSL_AD_DECODE_ERROR;
2842 SSLerr(SSL_F_TLS_PROCESS_CKE_GOST, SSL_R_DECRYPTION_FAILED);
2845 /* Generate master secret */
2846 if (!ssl_generate_master_secret(s, premaster_secret,
2847 sizeof(premaster_secret), 0)) {
2848 *al = SSL_AD_INTERNAL_ERROR;
2849 SSLerr(SSL_F_TLS_PROCESS_CKE_GOST, ERR_R_INTERNAL_ERROR);
2852 /* Check if pubkey from client certificate was used */
2853 if (EVP_PKEY_CTX_ctrl
2854 (pkey_ctx, -1, -1, EVP_PKEY_CTRL_PEER_KEY, 2, NULL) > 0)
2855 s->statem.no_cert_verify = 1;
2859 EVP_PKEY_CTX_free(pkey_ctx);
2862 /* Should never happen */
2863 *al = SSL_AD_INTERNAL_ERROR;
2864 SSLerr(SSL_F_TLS_PROCESS_CKE_GOST, ERR_R_INTERNAL_ERROR);
2869 MSG_PROCESS_RETURN tls_process_client_key_exchange(SSL *s, PACKET *pkt)
2872 unsigned long alg_k;
2874 alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
2876 /* For PSK parse and retrieve identity, obtain PSK key */
2877 if ((alg_k & SSL_PSK) && !tls_process_cke_psk_preamble(s, pkt, &al))
2880 if (alg_k & SSL_kPSK) {
2881 /* Identity extracted earlier: should be nothing left */
2882 if (PACKET_remaining(pkt) != 0) {
2883 al = SSL_AD_HANDSHAKE_FAILURE;
2884 SSLerr(SSL_F_TLS_PROCESS_CLIENT_KEY_EXCHANGE,
2885 SSL_R_LENGTH_MISMATCH);
2888 /* PSK handled by ssl_generate_master_secret */
2889 if (!ssl_generate_master_secret(s, NULL, 0, 0)) {
2890 al = SSL_AD_INTERNAL_ERROR;
2891 SSLerr(SSL_F_TLS_PROCESS_CLIENT_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
2894 } else if (alg_k & (SSL_kRSA | SSL_kRSAPSK)) {
2895 if (!tls_process_cke_rsa(s, pkt, &al))
2897 } else if (alg_k & (SSL_kDHE | SSL_kDHEPSK)) {
2898 if (!tls_process_cke_dhe(s, pkt, &al))
2900 } else if (alg_k & (SSL_kECDHE | SSL_kECDHEPSK)) {
2901 if (!tls_process_cke_ecdhe(s, pkt, &al))
2903 } else if (alg_k & SSL_kSRP) {
2904 if (!tls_process_cke_srp(s, pkt, &al))
2906 } else if (alg_k & SSL_kGOST) {
2907 if (!tls_process_cke_gost(s, pkt, &al))
2910 al = SSL_AD_HANDSHAKE_FAILURE;
2911 SSLerr(SSL_F_TLS_PROCESS_CLIENT_KEY_EXCHANGE,
2912 SSL_R_UNKNOWN_CIPHER_TYPE);
2916 return MSG_PROCESS_CONTINUE_PROCESSING;
2919 ssl3_send_alert(s, SSL3_AL_FATAL, al);
2920 #ifndef OPENSSL_NO_PSK
2921 OPENSSL_clear_free(s->s3->tmp.psk, s->s3->tmp.psklen);
2922 s->s3->tmp.psk = NULL;
2924 ossl_statem_set_error(s);
2925 return MSG_PROCESS_ERROR;
2928 WORK_STATE tls_post_process_client_key_exchange(SSL *s, WORK_STATE wst)
2930 #ifndef OPENSSL_NO_SCTP
2931 if (wst == WORK_MORE_A) {
2932 if (SSL_IS_DTLS(s)) {
2933 unsigned char sctpauthkey[64];
2934 char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
2936 * Add new shared key for SCTP-Auth, will be ignored if no SCTP
2939 memcpy(labelbuffer, DTLS1_SCTP_AUTH_LABEL,
2940 sizeof(DTLS1_SCTP_AUTH_LABEL));
2942 if (SSL_export_keying_material(s, sctpauthkey,
2943 sizeof(sctpauthkey), labelbuffer,
2944 sizeof(labelbuffer), NULL, 0,
2946 ossl_statem_set_error(s);
2950 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
2951 sizeof(sctpauthkey), sctpauthkey);
2956 if ((wst == WORK_MORE_B)
2958 && BIO_dgram_is_sctp(SSL_get_wbio(s))
2959 /* Are we renegotiating? */
2961 /* Are we going to skip the CertificateVerify? */
2962 && (s->session->peer == NULL || s->statem.no_cert_verify)
2963 && BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
2964 s->s3->in_read_app_data = 2;
2965 s->rwstate = SSL_READING;
2966 BIO_clear_retry_flags(SSL_get_rbio(s));
2967 BIO_set_retry_read(SSL_get_rbio(s));
2968 ossl_statem_set_sctp_read_sock(s, 1);
2971 ossl_statem_set_sctp_read_sock(s, 0);
2975 if (s->statem.no_cert_verify || !s->session->peer) {
2977 * No certificate verify or no peer certificate so we no longer need
2978 * the handshake_buffer
2980 if (!ssl3_digest_cached_records(s, 0)) {
2981 ossl_statem_set_error(s);
2984 return WORK_FINISHED_CONTINUE;
2986 if (!s->s3->handshake_buffer) {
2987 SSLerr(SSL_F_TLS_POST_PROCESS_CLIENT_KEY_EXCHANGE,
2988 ERR_R_INTERNAL_ERROR);
2989 ossl_statem_set_error(s);
2993 * For sigalgs freeze the handshake buffer. If we support
2994 * extms we've done this already so this is a no-op
2996 if (!ssl3_digest_cached_records(s, 1)) {
2997 ossl_statem_set_error(s);
3002 return WORK_FINISHED_CONTINUE;
3005 MSG_PROCESS_RETURN tls_process_client_certificate(SSL *s, PACKET *pkt)
3007 int i, al = SSL_AD_INTERNAL_ERROR, ret = MSG_PROCESS_ERROR;
3009 unsigned long l, llen;
3010 const unsigned char *certstart, *certbytes;
3011 STACK_OF(X509) *sk = NULL;
3012 PACKET spkt, context;
3015 if ((sk = sk_X509_new_null()) == NULL) {
3016 SSLerr(SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, ERR_R_MALLOC_FAILURE);
3020 /* TODO(TLS1.3): For now we ignore the context. We need to verify this */
3021 if ((SSL_IS_TLS13(s) && !PACKET_get_length_prefixed_1(pkt, &context))
3022 || !PACKET_get_net_3(pkt, &llen)
3023 || !PACKET_get_sub_packet(pkt, &spkt, llen)
3024 || PACKET_remaining(pkt) != 0) {
3025 al = SSL_AD_DECODE_ERROR;
3026 SSLerr(SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, SSL_R_LENGTH_MISMATCH);
3030 for (chainidx = 0; PACKET_remaining(&spkt) > 0; chainidx++) {
3031 if (!PACKET_get_net_3(&spkt, &l)
3032 || !PACKET_get_bytes(&spkt, &certbytes, l)) {
3033 al = SSL_AD_DECODE_ERROR;
3034 SSLerr(SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
3035 SSL_R_CERT_LENGTH_MISMATCH);
3039 certstart = certbytes;
3040 x = d2i_X509(NULL, (const unsigned char **)&certbytes, l);
3042 SSLerr(SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, ERR_R_ASN1_LIB);
3045 if (certbytes != (certstart + l)) {
3046 al = SSL_AD_DECODE_ERROR;
3047 SSLerr(SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
3048 SSL_R_CERT_LENGTH_MISMATCH);
3052 if (SSL_IS_TLS13(s)) {
3053 RAW_EXTENSION *rawexts = NULL;
3056 if (!PACKET_get_length_prefixed_2(&spkt, &extensions)) {
3057 al = SSL_AD_DECODE_ERROR;
3058 SSLerr(SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, SSL_R_BAD_LENGTH);
3061 if (!tls_collect_extensions(s, &extensions, EXT_TLS1_3_CERTIFICATE,
3063 || !tls_parse_all_extensions(s, EXT_TLS1_3_CERTIFICATE,
3064 rawexts, x, chainidx, &al))
3068 if (!sk_X509_push(sk, x)) {
3069 SSLerr(SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, ERR_R_MALLOC_FAILURE);
3075 if (sk_X509_num(sk) <= 0) {
3076 /* TLS does not mind 0 certs returned */
3077 if (s->version == SSL3_VERSION) {
3078 al = SSL_AD_HANDSHAKE_FAILURE;
3079 SSLerr(SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
3080 SSL_R_NO_CERTIFICATES_RETURNED);
3083 /* Fail for TLS only if we required a certificate */
3084 else if ((s->verify_mode & SSL_VERIFY_PEER) &&
3085 (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) {
3086 SSLerr(SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
3087 SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE);
3088 al = SSL_AD_HANDSHAKE_FAILURE;
3091 /* No client certificate so digest cached records */
3092 if (s->s3->handshake_buffer && !ssl3_digest_cached_records(s, 0)) {
3097 i = ssl_verify_cert_chain(s, sk);
3099 al = ssl_verify_alarm_type(s->verify_result);
3100 SSLerr(SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
3101 SSL_R_CERTIFICATE_VERIFY_FAILED);
3105 SSLerr(SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, i);
3106 al = SSL_AD_HANDSHAKE_FAILURE;
3109 pkey = X509_get0_pubkey(sk_X509_value(sk, 0));
3111 al = SSL3_AD_HANDSHAKE_FAILURE;
3112 SSLerr(SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE,
3113 SSL_R_UNKNOWN_CERTIFICATE_TYPE);
3118 X509_free(s->session->peer);
3119 s->session->peer = sk_X509_shift(sk);
3120 s->session->verify_result = s->verify_result;
3122 sk_X509_pop_free(s->session->peer_chain, X509_free);
3123 s->session->peer_chain = sk;
3126 * Freeze the handshake buffer. For <TLS1.3 we do this after the CKE
3129 if (SSL_IS_TLS13(s) && !ssl3_digest_cached_records(s, 1)) {
3130 al = SSL_AD_INTERNAL_ERROR;
3131 SSLerr(SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, ERR_R_INTERNAL_ERROR);
3136 * Inconsistency alert: cert_chain does *not* include the peer's own
3137 * certificate, while we do include it in statem_clnt.c
3141 /* Save the current hash state for when we receive the CertificateVerify */
3143 && !ssl_handshake_hash(s, s->cert_verify_hash,
3144 sizeof(s->cert_verify_hash),
3145 &s->cert_verify_hash_len)) {
3146 al = SSL_AD_INTERNAL_ERROR;
3147 SSLerr(SSL_F_TLS_PROCESS_CLIENT_CERTIFICATE, ERR_R_INTERNAL_ERROR);
3151 ret = MSG_PROCESS_CONTINUE_READING;
3155 ssl3_send_alert(s, SSL3_AL_FATAL, al);
3156 ossl_statem_set_error(s);
3159 sk_X509_pop_free(sk, X509_free);
3163 int tls_construct_server_certificate(SSL *s, WPACKET *pkt)
3166 int al = SSL_AD_INTERNAL_ERROR;
3168 cpk = ssl_get_server_send_pkey(s);
3170 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_CERTIFICATE, ERR_R_INTERNAL_ERROR);
3175 * In TLSv1.3 the certificate chain is always preceded by a 0 length context
3176 * for the server Certificate message
3178 if ((SSL_IS_TLS13(s) && !WPACKET_put_bytes_u8(pkt, 0))
3179 || !ssl3_output_cert_chain(s, pkt, cpk, &al)) {
3180 SSLerr(SSL_F_TLS_CONSTRUCT_SERVER_CERTIFICATE, ERR_R_INTERNAL_ERROR);
3181 ssl3_send_alert(s, SSL3_AL_FATAL, al);
3188 int tls_construct_new_session_ticket(SSL *s, WPACKET *pkt)
3190 unsigned char *senc = NULL;
3191 EVP_CIPHER_CTX *ctx = NULL;
3192 HMAC_CTX *hctx = NULL;
3193 unsigned char *p, *encdata1, *encdata2, *macdata1, *macdata2;
3194 const unsigned char *const_p;
3195 int len, slen_full, slen, lenfinal;
3198 SSL_CTX *tctx = s->initial_ctx;
3199 unsigned char iv[EVP_MAX_IV_LENGTH];
3200 unsigned char key_name[TLSEXT_KEYNAME_LENGTH];
3202 size_t macoffset, macendoffset;
3204 /* get session encoding length */
3205 slen_full = i2d_SSL_SESSION(s->session, NULL);
3207 * Some length values are 16 bits, so forget it if session is too
3210 if (slen_full == 0 || slen_full > 0xFF00) {
3211 ossl_statem_set_error(s);
3214 senc = OPENSSL_malloc(slen_full);
3216 ossl_statem_set_error(s);
3220 ctx = EVP_CIPHER_CTX_new();
3221 hctx = HMAC_CTX_new();
3222 if (ctx == NULL || hctx == NULL) {
3223 SSLerr(SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_MALLOC_FAILURE);
3228 if (!i2d_SSL_SESSION(s->session, &p))
3232 * create a fresh copy (not shared with other threads) to clean up
3235 sess = d2i_SSL_SESSION(NULL, &const_p, slen_full);
3238 sess->session_id_length = 0; /* ID is irrelevant for the ticket */
3240 slen = i2d_SSL_SESSION(sess, NULL);
3241 if (slen == 0 || slen > slen_full) { /* shouldn't ever happen */
3242 SSL_SESSION_free(sess);
3246 if (!i2d_SSL_SESSION(sess, &p)) {
3247 SSL_SESSION_free(sess);
3250 SSL_SESSION_free(sess);
3253 * Initialize HMAC and cipher contexts. If callback present it does
3254 * all the work otherwise use generated values from parent ctx.
3256 if (tctx->ext.ticket_key_cb) {
3257 /* if 0 is returned, write an empty ticket */
3258 int ret = tctx->ext.ticket_key_cb(s, key_name, iv, ctx,
3263 /* Put timeout and length */
3264 if (!WPACKET_put_bytes_u32(pkt, 0)
3265 || !WPACKET_put_bytes_u16(pkt, 0)) {
3266 SSLerr(SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET,
3267 ERR_R_INTERNAL_ERROR);
3271 EVP_CIPHER_CTX_free(ctx);
3272 HMAC_CTX_free(hctx);
3277 iv_len = EVP_CIPHER_CTX_iv_length(ctx);
3279 const EVP_CIPHER *cipher = EVP_aes_256_cbc();
3281 iv_len = EVP_CIPHER_iv_length(cipher);
3282 if (RAND_bytes(iv, iv_len) <= 0)
3284 if (!EVP_EncryptInit_ex(ctx, cipher, NULL,
3285 tctx->ext.tick_aes_key, iv))
3287 if (!HMAC_Init_ex(hctx, tctx->ext.tick_hmac_key,
3288 sizeof(tctx->ext.tick_hmac_key),
3289 EVP_sha256(), NULL))
3291 memcpy(key_name, tctx->ext.tick_key_name,
3292 sizeof(tctx->ext.tick_key_name));
3296 * Ticket lifetime hint (advisory only): We leave this unspecified
3297 * for resumed session (for simplicity), and guess that tickets for
3298 * new sessions will live as long as their sessions.
3300 if (!WPACKET_put_bytes_u32(pkt, s->hit ? 0 : s->session->timeout)
3301 /* Now the actual ticket data */
3302 || !WPACKET_start_sub_packet_u16(pkt)
3303 || !WPACKET_get_total_written(pkt, &macoffset)
3304 /* Output key name */
3305 || !WPACKET_memcpy(pkt, key_name, sizeof(key_name))
3307 || !WPACKET_memcpy(pkt, iv, iv_len)
3308 || !WPACKET_reserve_bytes(pkt, slen + EVP_MAX_BLOCK_LENGTH,
3310 /* Encrypt session data */
3311 || !EVP_EncryptUpdate(ctx, encdata1, &len, senc, slen)
3312 || !WPACKET_allocate_bytes(pkt, len, &encdata2)
3313 || encdata1 != encdata2
3314 || !EVP_EncryptFinal(ctx, encdata1 + len, &lenfinal)
3315 || !WPACKET_allocate_bytes(pkt, lenfinal, &encdata2)
3316 || encdata1 + len != encdata2
3317 || len + lenfinal > slen + EVP_MAX_BLOCK_LENGTH
3318 || !WPACKET_get_total_written(pkt, &macendoffset)
3319 || !HMAC_Update(hctx,
3320 (unsigned char *)s->init_buf->data + macoffset,
3321 macendoffset - macoffset)
3322 || !WPACKET_reserve_bytes(pkt, EVP_MAX_MD_SIZE, &macdata1)
3323 || !HMAC_Final(hctx, macdata1, &hlen)
3324 || hlen > EVP_MAX_MD_SIZE
3325 || !WPACKET_allocate_bytes(pkt, hlen, &macdata2)
3326 || macdata1 != macdata2
3327 || !WPACKET_close(pkt)) {
3328 SSLerr(SSL_F_TLS_CONSTRUCT_NEW_SESSION_TICKET, ERR_R_INTERNAL_ERROR);
3331 EVP_CIPHER_CTX_free(ctx);
3332 HMAC_CTX_free(hctx);
3338 EVP_CIPHER_CTX_free(ctx);
3339 HMAC_CTX_free(hctx);
3340 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
3345 * In TLSv1.3 this is called from the extensions code, otherwise it is used to
3346 * create a separate message. Returns 1 on success or 0 on failure.
3348 int tls_construct_cert_status_body(SSL *s, WPACKET *pkt)
3350 if (!WPACKET_put_bytes_u8(pkt, s->ext.status_type)
3351 || !WPACKET_sub_memcpy_u24(pkt, s->ext.ocsp.resp,
3352 s->ext.ocsp.resp_len)) {
3353 SSLerr(SSL_F_TLS_CONSTRUCT_CERT_STATUS_BODY, ERR_R_INTERNAL_ERROR);
3360 int tls_construct_cert_status(SSL *s, WPACKET *pkt)
3362 if (!tls_construct_cert_status_body(s, pkt)) {
3363 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
3370 #ifndef OPENSSL_NO_NEXTPROTONEG
3372 * tls_process_next_proto reads a Next Protocol Negotiation handshake message.
3373 * It sets the next_proto member in s if found
3375 MSG_PROCESS_RETURN tls_process_next_proto(SSL *s, PACKET *pkt)
3377 PACKET next_proto, padding;
3378 size_t next_proto_len;
3381 * The payload looks like:
3383 * uint8 proto[proto_len];
3384 * uint8 padding_len;
3385 * uint8 padding[padding_len];
3387 if (!PACKET_get_length_prefixed_1(pkt, &next_proto)
3388 || !PACKET_get_length_prefixed_1(pkt, &padding)
3389 || PACKET_remaining(pkt) > 0) {
3390 SSLerr(SSL_F_TLS_PROCESS_NEXT_PROTO, SSL_R_LENGTH_MISMATCH);
3394 if (!PACKET_memdup(&next_proto, &s->ext.npn, &next_proto_len)) {
3399 s->ext.npn_len = (unsigned char)next_proto_len;
3401 return MSG_PROCESS_CONTINUE_READING;
3403 ossl_statem_set_error(s);
3404 return MSG_PROCESS_ERROR;
3408 static int tls_construct_encrypted_extensions(SSL *s, WPACKET *pkt)
3412 if (!tls_construct_extensions(s, pkt, EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
3414 ssl3_send_alert(s, SSL3_AL_FATAL, al);
3415 SSLerr(SSL_F_TLS_CONSTRUCT_ENCRYPTED_EXTENSIONS, ERR_R_INTERNAL_ERROR);
3416 ssl3_send_alert(s, SSL3_AL_FATAL, al);
3423 #define SSLV2_CIPHER_LEN 3
3425 STACK_OF(SSL_CIPHER) *ssl_bytes_to_cipher_list(SSL *s,
3426 PACKET *cipher_suites,
3427 STACK_OF(SSL_CIPHER) **skp,
3428 int sslv2format, int *al)
3430 const SSL_CIPHER *c;
3431 STACK_OF(SSL_CIPHER) *sk;
3433 /* 3 = SSLV2_CIPHER_LEN > TLS_CIPHER_LEN = 2. */
3434 unsigned char cipher[SSLV2_CIPHER_LEN];
3436 s->s3->send_connection_binding = 0;
3438 n = sslv2format ? SSLV2_CIPHER_LEN : TLS_CIPHER_LEN;
3440 if (PACKET_remaining(cipher_suites) == 0) {
3441 SSLerr(SSL_F_SSL_BYTES_TO_CIPHER_LIST, SSL_R_NO_CIPHERS_SPECIFIED);
3442 *al = SSL_AD_ILLEGAL_PARAMETER;
3446 if (PACKET_remaining(cipher_suites) % n != 0) {
3447 SSLerr(SSL_F_SSL_BYTES_TO_CIPHER_LIST,
3448 SSL_R_ERROR_IN_RECEIVED_CIPHER_LIST);
3449 *al = SSL_AD_DECODE_ERROR;
3453 if ((skp == NULL) || (*skp == NULL)) {
3454 sk = sk_SSL_CIPHER_new_null(); /* change perhaps later */
3456 SSLerr(SSL_F_SSL_BYTES_TO_CIPHER_LIST, ERR_R_MALLOC_FAILURE);
3457 *al = SSL_AD_INTERNAL_ERROR;
3462 sk_SSL_CIPHER_zero(sk);
3465 if (!PACKET_memdup(cipher_suites, &s->s3->tmp.ciphers_raw,
3466 &s->s3->tmp.ciphers_rawlen)) {
3467 *al = SSL_AD_INTERNAL_ERROR;
3471 while (PACKET_copy_bytes(cipher_suites, cipher, n)) {
3473 * SSLv3 ciphers wrapped in an SSLv2-compatible ClientHello have the
3474 * first byte set to zero, while true SSLv2 ciphers have a non-zero
3475 * first byte. We don't support any true SSLv2 ciphers, so skip them.
3477 if (sslv2format && cipher[0] != '\0')
3480 /* Check for TLS_EMPTY_RENEGOTIATION_INFO_SCSV */
3481 if ((cipher[n - 2] == ((SSL3_CK_SCSV >> 8) & 0xff)) &&
3482 (cipher[n - 1] == (SSL3_CK_SCSV & 0xff))) {
3483 /* SCSV fatal if renegotiating */
3484 if (s->renegotiate) {
3485 SSLerr(SSL_F_SSL_BYTES_TO_CIPHER_LIST,
3486 SSL_R_SCSV_RECEIVED_WHEN_RENEGOTIATING);
3487 *al = SSL_AD_HANDSHAKE_FAILURE;
3490 s->s3->send_connection_binding = 1;
3494 /* Check for TLS_FALLBACK_SCSV */
3495 if ((cipher[n - 2] == ((SSL3_CK_FALLBACK_SCSV >> 8) & 0xff)) &&
3496 (cipher[n - 1] == (SSL3_CK_FALLBACK_SCSV & 0xff))) {
3498 * The SCSV indicates that the client previously tried a higher
3499 * version. Fail if the current version is an unexpected
3502 if (!ssl_check_version_downgrade(s)) {
3503 SSLerr(SSL_F_SSL_BYTES_TO_CIPHER_LIST,
3504 SSL_R_INAPPROPRIATE_FALLBACK);
3505 *al = SSL_AD_INAPPROPRIATE_FALLBACK;
3511 /* For SSLv2-compat, ignore leading 0-byte. */
3512 c = ssl_get_cipher_by_char(s, sslv2format ? &cipher[1] : cipher);
3514 if (!sk_SSL_CIPHER_push(sk, c)) {
3515 SSLerr(SSL_F_SSL_BYTES_TO_CIPHER_LIST, ERR_R_MALLOC_FAILURE);
3516 *al = SSL_AD_INTERNAL_ERROR;
3521 if (PACKET_remaining(cipher_suites) > 0) {
3522 *al = SSL_AD_INTERNAL_ERROR;
3523 SSLerr(SSL_F_SSL_BYTES_TO_CIPHER_LIST, ERR_R_INTERNAL_ERROR);
3531 if ((skp == NULL) || (*skp == NULL))
3532 sk_SSL_CIPHER_free(sk);