RT 1530; fix incorrect comment
[openssl.git] / ssl / s3_srvr.c
1 /* ssl/s3_srvr.c -*- mode:C; c-file-style: "eay" -*- */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3  * All rights reserved.
4  *
5  * This package is an SSL implementation written
6  * by Eric Young (eay@cryptsoft.com).
7  * The implementation was written so as to conform with Netscapes SSL.
8  * 
9  * This library is free for commercial and non-commercial use as long as
10  * the following conditions are aheared to.  The following conditions
11  * apply to all code found in this distribution, be it the RC4, RSA,
12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13  * included with this distribution is covered by the same copyright terms
14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15  * 
16  * Copyright remains Eric Young's, and as such any Copyright notices in
17  * the code are not to be removed.
18  * If this package is used in a product, Eric Young should be given attribution
19  * as the author of the parts of the library used.
20  * This can be in the form of a textual message at program startup or
21  * in documentation (online or textual) provided with the package.
22  * 
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *    "This product includes cryptographic software written by
34  *     Eric Young (eay@cryptsoft.com)"
35  *    The word 'cryptographic' can be left out if the rouines from the library
36  *    being used are not cryptographic related :-).
37  * 4. If you include any Windows specific code (or a derivative thereof) from 
38  *    the apps directory (application code) you must include an acknowledgement:
39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40  * 
41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  * 
53  * The licence and distribution terms for any publically available version or
54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
55  * copied and put under another distribution licence
56  * [including the GNU Public Licence.]
57  */
58 /* ====================================================================
59  * Copyright (c) 1998-2007 The OpenSSL Project.  All rights reserved.
60  *
61  * Redistribution and use in source and binary forms, with or without
62  * modification, are permitted provided that the following conditions
63  * are met:
64  *
65  * 1. Redistributions of source code must retain the above copyright
66  *    notice, this list of conditions and the following disclaimer. 
67  *
68  * 2. Redistributions in binary form must reproduce the above copyright
69  *    notice, this list of conditions and the following disclaimer in
70  *    the documentation and/or other materials provided with the
71  *    distribution.
72  *
73  * 3. All advertising materials mentioning features or use of this
74  *    software must display the following acknowledgment:
75  *    "This product includes software developed by the OpenSSL Project
76  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
77  *
78  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
79  *    endorse or promote products derived from this software without
80  *    prior written permission. For written permission, please contact
81  *    openssl-core@openssl.org.
82  *
83  * 5. Products derived from this software may not be called "OpenSSL"
84  *    nor may "OpenSSL" appear in their names without prior written
85  *    permission of the OpenSSL Project.
86  *
87  * 6. Redistributions of any form whatsoever must retain the following
88  *    acknowledgment:
89  *    "This product includes software developed by the OpenSSL Project
90  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
91  *
92  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
93  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
95  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
96  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
97  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
98  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
99  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
101  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
102  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
103  * OF THE POSSIBILITY OF SUCH DAMAGE.
104  * ====================================================================
105  *
106  * This product includes cryptographic software written by Eric Young
107  * (eay@cryptsoft.com).  This product includes software written by Tim
108  * Hudson (tjh@cryptsoft.com).
109  *
110  */
111 /* ====================================================================
112  * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
113  *
114  * Portions of the attached software ("Contribution") are developed by 
115  * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project.
116  *
117  * The Contribution is licensed pursuant to the OpenSSL open source
118  * license provided above.
119  *
120  * ECC cipher suite support in OpenSSL originally written by
121  * Vipul Gupta and Sumit Gupta of Sun Microsystems Laboratories.
122  *
123  */
124 /* ====================================================================
125  * Copyright 2005 Nokia. All rights reserved.
126  *
127  * The portions of the attached software ("Contribution") is developed by
128  * Nokia Corporation and is licensed pursuant to the OpenSSL open source
129  * license.
130  *
131  * The Contribution, originally written by Mika Kousa and Pasi Eronen of
132  * Nokia Corporation, consists of the "PSK" (Pre-Shared Key) ciphersuites
133  * support (see RFC 4279) to OpenSSL.
134  *
135  * No patent licenses or other rights except those expressly stated in
136  * the OpenSSL open source license shall be deemed granted or received
137  * expressly, by implication, estoppel, or otherwise.
138  *
139  * No assurances are provided by Nokia that the Contribution does not
140  * infringe the patent or other intellectual property rights of any third
141  * party or that the license provides you with all the necessary rights
142  * to make use of the Contribution.
143  *
144  * THE SOFTWARE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. IN
145  * ADDITION TO THE DISCLAIMERS INCLUDED IN THE LICENSE, NOKIA
146  * SPECIFICALLY DISCLAIMS ANY LIABILITY FOR CLAIMS BROUGHT BY YOU OR ANY
147  * OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OR
148  * OTHERWISE.
149  */
150
151 #define REUSE_CIPHER_BUG
152 #define NETSCAPE_HANG_BUG
153
154 #include <stdio.h>
155 #include "ssl_locl.h"
156 #include "kssl_lcl.h"
157 #include <openssl/buffer.h>
158 #include <openssl/rand.h>
159 #include <openssl/objects.h>
160 #include <openssl/evp.h>
161 #include <openssl/hmac.h>
162 #include <openssl/x509.h>
163 #ifndef OPENSSL_NO_DH
164 #include <openssl/dh.h>
165 #endif
166 #include <openssl/bn.h>
167 #ifndef OPENSSL_NO_KRB5
168 #include <openssl/krb5_asn.h>
169 #endif
170 #include <openssl/md5.h>
171
172 static const SSL_METHOD *ssl3_get_server_method(int ver);
173
174 static const SSL_METHOD *ssl3_get_server_method(int ver)
175         {
176         if (ver == SSL3_VERSION)
177                 return(SSLv3_server_method());
178         else
179                 return(NULL);
180         }
181
182 #ifndef OPENSSL_NO_SRP
183 static int ssl_check_srp_ext_ClientHello(SSL *s, int *al)
184         {
185         int ret = SSL_ERROR_NONE;
186
187         *al = SSL_AD_UNRECOGNIZED_NAME;
188
189         if ((s->s3->tmp.new_cipher->algorithm_mkey & SSL_kSRP) &&
190             (s->srp_ctx.TLS_ext_srp_username_callback != NULL))
191                 {
192                 if(s->srp_ctx.login == NULL)
193                         {
194                         /* RFC 5054 says SHOULD reject, 
195                            we do so if There is no srp login name */
196                         ret = SSL3_AL_FATAL;
197                         *al = SSL_AD_UNKNOWN_PSK_IDENTITY;
198                         }
199                 else
200                         {
201                         ret = SSL_srp_server_param_with_username(s,al);
202                         }
203                 }
204         return ret;
205         }
206 #endif
207
208 IMPLEMENT_ssl3_meth_func(SSLv3_server_method,
209                         ssl3_accept,
210                         ssl_undefined_function,
211                         ssl3_get_server_method)
212
213 int ssl3_accept(SSL *s)
214         {
215         BUF_MEM *buf;
216         unsigned long alg_k,Time=(unsigned long)time(NULL);
217         void (*cb)(const SSL *ssl,int type,int val)=NULL;
218         int ret= -1;
219         int new_state,state,skip=0;
220
221         RAND_add(&Time,sizeof(Time),0);
222         ERR_clear_error();
223         clear_sys_error();
224
225         if (s->info_callback != NULL)
226                 cb=s->info_callback;
227         else if (s->ctx->info_callback != NULL)
228                 cb=s->ctx->info_callback;
229
230         /* init things to blank */
231         s->in_handshake++;
232         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
233
234         if (s->cert == NULL)
235                 {
236                 SSLerr(SSL_F_SSL3_ACCEPT,SSL_R_NO_CERTIFICATE_SET);
237                 return(-1);
238                 }
239
240 #ifndef OPENSSL_NO_HEARTBEATS
241         /* If we're awaiting a HeartbeatResponse, pretend we
242          * already got and don't await it anymore, because
243          * Heartbeats don't make sense during handshakes anyway.
244          */
245         if (s->tlsext_hb_pending)
246                 {
247                 s->tlsext_hb_pending = 0;
248                 s->tlsext_hb_seq++;
249                 }
250 #endif
251
252         for (;;)
253                 {
254                 state=s->state;
255
256                 switch (s->state)
257                         {
258                 case SSL_ST_RENEGOTIATE:
259                         s->renegotiate=1;
260                         /* s->state=SSL_ST_ACCEPT; */
261
262                 case SSL_ST_BEFORE:
263                 case SSL_ST_ACCEPT:
264                 case SSL_ST_BEFORE|SSL_ST_ACCEPT:
265                 case SSL_ST_OK|SSL_ST_ACCEPT:
266
267                         s->server=1;
268                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
269
270                         if ((s->version>>8) != 3)
271                                 {
272                                 SSLerr(SSL_F_SSL3_ACCEPT, ERR_R_INTERNAL_ERROR);
273                                 return -1;
274                                 }
275
276                         if (!ssl_security(s, SSL_SECOP_VERSION, 0,
277                                                         s->version, NULL))
278                                 {
279                                 SSLerr(SSL_F_SSL3_ACCEPT, SSL_R_VERSION_TOO_LOW);
280                                 return -1;
281                                 }
282
283                         s->type=SSL_ST_ACCEPT;
284
285                         if (s->init_buf == NULL)
286                                 {
287                                 if ((buf=BUF_MEM_new()) == NULL)
288                                         {
289                                         ret= -1;
290                                         goto end;
291                                         }
292                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
293                                         {
294                                         ret= -1;
295                                         goto end;
296                                         }
297                                 s->init_buf=buf;
298                                 }
299
300                         if (!ssl3_setup_buffers(s))
301                                 {
302                                 ret= -1;
303                                 goto end;
304                                 }
305
306                         s->init_num=0;
307                         s->s3->flags &= ~SSL3_FLAGS_SGC_RESTART_DONE;
308                         s->s3->flags &= ~TLS1_FLAGS_SKIP_CERT_VERIFY;
309
310                         if (s->state != SSL_ST_RENEGOTIATE)
311                                 {
312                                 /* Ok, we now need to push on a buffering BIO so that
313                                  * the output is sent in a way that TCP likes :-)
314                                  */
315                                 if (!ssl_init_wbio_buffer(s,1)) { ret= -1; goto end; }
316                                 
317                                 ssl3_init_finished_mac(s);
318                                 s->state=SSL3_ST_SR_CLNT_HELLO_A;
319                                 s->ctx->stats.sess_accept++;
320                                 }
321                         else if (!s->s3->send_connection_binding &&
322                                 !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
323                                 {
324                                 /* Server attempting to renegotiate with
325                                  * client that doesn't support secure
326                                  * renegotiation.
327                                  */
328                                 SSLerr(SSL_F_SSL3_ACCEPT, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
329                                 ssl3_send_alert(s,SSL3_AL_FATAL,SSL_AD_HANDSHAKE_FAILURE);
330                                 ret = -1;
331                                 goto end;
332                                 }
333                         else
334                                 {
335                                 /* s->state == SSL_ST_RENEGOTIATE,
336                                  * we will just send a HelloRequest */
337                                 s->ctx->stats.sess_accept_renegotiate++;
338                                 s->state=SSL3_ST_SW_HELLO_REQ_A;
339                                 }
340                         break;
341
342                 case SSL3_ST_SW_HELLO_REQ_A:
343                 case SSL3_ST_SW_HELLO_REQ_B:
344
345                         s->shutdown=0;
346                         ret=ssl3_send_hello_request(s);
347                         if (ret <= 0) goto end;
348                         s->s3->tmp.next_state=SSL3_ST_SW_HELLO_REQ_C;
349                         s->state=SSL3_ST_SW_FLUSH;
350                         s->init_num=0;
351
352                         ssl3_init_finished_mac(s);
353                         break;
354
355                 case SSL3_ST_SW_HELLO_REQ_C:
356                         s->state=SSL_ST_OK;
357                         break;
358
359                 case SSL3_ST_SR_CLNT_HELLO_A:
360                 case SSL3_ST_SR_CLNT_HELLO_B:
361                 case SSL3_ST_SR_CLNT_HELLO_C:
362
363                         ret=ssl3_get_client_hello(s);
364                         if (ret <= 0) goto end;
365 #ifndef OPENSSL_NO_SRP
366                         s->state = SSL3_ST_SR_CLNT_HELLO_D;
367                 case SSL3_ST_SR_CLNT_HELLO_D:
368                         {
369                         int al;
370                         if ((ret = ssl_check_srp_ext_ClientHello(s,&al))  < 0)
371                                         {
372                                         /* callback indicates firther work to be done */
373                                         s->rwstate=SSL_X509_LOOKUP;
374                                         goto end;
375                                         }
376                         if (ret != SSL_ERROR_NONE)
377                                 {
378                                 ssl3_send_alert(s,SSL3_AL_FATAL,al);    
379                                 /* This is not really an error but the only means to
380                                    for a client to detect whether srp is supported. */
381                                    if (al != TLS1_AD_UNKNOWN_PSK_IDENTITY)      
382                                         SSLerr(SSL_F_SSL3_ACCEPT,SSL_R_CLIENTHELLO_TLSEXT);                     
383                                 ret = SSL_TLSEXT_ERR_ALERT_FATAL;                       
384                                 ret= -1;
385                                 goto end;       
386                                 }
387                         }
388 #endif          
389                         
390                         s->renegotiate = 2;
391                         s->state=SSL3_ST_SW_SRVR_HELLO_A;
392                         s->init_num=0;
393                         break;
394
395                 case SSL3_ST_SW_SRVR_HELLO_A:
396                 case SSL3_ST_SW_SRVR_HELLO_B:
397                         ret=ssl3_send_server_hello(s);
398                         if (ret <= 0) goto end;
399 #ifndef OPENSSL_NO_TLSEXT
400                         if (s->hit)
401                                 {
402                                 if (s->tlsext_ticket_expected)
403                                         s->state=SSL3_ST_SW_SESSION_TICKET_A;
404                                 else
405                                         s->state=SSL3_ST_SW_CHANGE_A;
406                                 }
407 #else
408                         if (s->hit)
409                                         s->state=SSL3_ST_SW_CHANGE_A;
410 #endif
411                         else
412 #ifndef OPENSSL_NO_TLSEXT
413                                 s->state = SSL3_ST_SW_SUPPLEMENTAL_DATA_A;
414 #else
415                         s->state = SSL3_ST_SW_CERT_A;
416 #endif
417                         s->init_num = 0;
418                         break;
419
420 #ifndef OPENSSL_NO_TLSEXT
421                 case SSL3_ST_SW_SUPPLEMENTAL_DATA_A:
422                 case SSL3_ST_SW_SUPPLEMENTAL_DATA_B:
423                         ret = tls1_send_server_supplemental_data(s, &skip);
424                         if (ret <= 0) goto end;
425
426                         s->state = SSL3_ST_SW_CERT_A;
427                         s->init_num = 0;
428                         break;
429 #endif
430
431                 case SSL3_ST_SW_CERT_A:
432                 case SSL3_ST_SW_CERT_B:
433                         /* Check if it is anon DH or anon ECDH, */
434                         /* normal PSK or KRB5 or SRP */
435                         if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL)
436                                 && !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK)
437                                 && !(s->s3->tmp.new_cipher->algorithm_auth & SSL_aKRB5))
438                                 {
439                                 ret=ssl3_send_server_certificate(s);
440                                 if (ret <= 0) goto end;
441 #ifndef OPENSSL_NO_TLSEXT
442                                 if (s->tlsext_status_expected)
443                                         s->state=SSL3_ST_SW_CERT_STATUS_A;
444                                 else
445                                         s->state=SSL3_ST_SW_KEY_EXCH_A;
446                                 }
447                         else
448                                 {
449                                 skip = 1;
450                                 s->state=SSL3_ST_SW_KEY_EXCH_A;
451                                 }
452 #else
453                                 }
454                         else
455                                 skip=1;
456
457                         s->state=SSL3_ST_SW_KEY_EXCH_A;
458 #endif
459                         s->init_num=0;
460                         break;
461
462                 case SSL3_ST_SW_KEY_EXCH_A:
463                 case SSL3_ST_SW_KEY_EXCH_B:
464                         alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
465
466                         /* clear this, it may get reset by
467                          * send_server_key_exchange */
468                         if ((s->options & SSL_OP_EPHEMERAL_RSA)
469 #ifndef OPENSSL_NO_KRB5
470                                 && !(alg_k & SSL_kKRB5)
471 #endif /* OPENSSL_NO_KRB5 */
472                                 )
473                                 /* option SSL_OP_EPHEMERAL_RSA sends temporary RSA key
474                                  * even when forbidden by protocol specs
475                                  * (handshake may fail as clients are not required to
476                                  * be able to handle this) */
477                                 s->s3->tmp.use_rsa_tmp=1;
478                         else
479                                 s->s3->tmp.use_rsa_tmp=0;
480
481
482                         /* only send if a DH key exchange, fortezza or
483                          * RSA but we have a sign only certificate
484                          *
485                          * PSK: may send PSK identity hints
486                          *
487                          * For ECC ciphersuites, we send a serverKeyExchange
488                          * message only if the cipher suite is either
489                          * ECDH-anon or ECDHE. In other cases, the
490                          * server certificate contains the server's
491                          * public key for key exchange.
492                          */
493                         if (s->s3->tmp.use_rsa_tmp
494                         /* PSK: send ServerKeyExchange if PSK identity
495                          * hint if provided */
496 #ifndef OPENSSL_NO_PSK
497                             || ((alg_k & SSL_kPSK) && s->ctx->psk_identity_hint)
498 #endif
499 #ifndef OPENSSL_NO_SRP
500                             /* SRP: send ServerKeyExchange */
501                             || (alg_k & SSL_kSRP)
502 #endif
503                             || (alg_k & SSL_kDHE)
504                             || (alg_k & SSL_kECDHE)
505                             || ((alg_k & SSL_kRSA)
506                                 && (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
507                                     || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
508                                         && EVP_PKEY_size(s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey)*8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
509                                         )
510                                     )
511                                 )
512                             )
513                                 {
514                                 ret=ssl3_send_server_key_exchange(s);
515                                 if (ret <= 0) goto end;
516                                 }
517                         else
518                                 skip=1;
519
520                         s->state=SSL3_ST_SW_CERT_REQ_A;
521                         s->init_num=0;
522                         break;
523
524                 case SSL3_ST_SW_CERT_REQ_A:
525                 case SSL3_ST_SW_CERT_REQ_B:
526                         if (/* don't request cert unless asked for it: */
527                                 !(s->verify_mode & SSL_VERIFY_PEER) ||
528                                 /* if SSL_VERIFY_CLIENT_ONCE is set,
529                                  * don't request cert during re-negotiation: */
530                                 ((s->session->peer != NULL) &&
531                                  (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
532                                 /* never request cert in anonymous ciphersuites
533                                  * (see section "Certificate request" in SSL 3 drafts
534                                  * and in RFC 2246): */
535                                 ((s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) &&
536                                  /* ... except when the application insists on verification
537                                   * (against the specs, but s3_clnt.c accepts this for SSL 3) */
538                                  !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) ||
539                                  /* never request cert in Kerberos ciphersuites */
540                                 (s->s3->tmp.new_cipher->algorithm_auth & SSL_aKRB5)
541                                 /* With normal PSK Certificates and
542                                  * Certificate Requests are omitted */
543                                 || (s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
544                                 {
545                                 /* no cert request */
546                                 skip=1;
547                                 s->s3->tmp.cert_request=0;
548                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
549                                 if (s->s3->handshake_buffer)
550                                         if (!ssl3_digest_cached_records(s))
551                                                 return -1;
552                                 }
553                         else
554                                 {
555                                 s->s3->tmp.cert_request=1;
556                                 ret=ssl3_send_certificate_request(s);
557                                 if (ret <= 0) goto end;
558 #ifndef NETSCAPE_HANG_BUG
559                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
560 #else
561                                 s->state=SSL3_ST_SW_FLUSH;
562                                 s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
563 #endif
564                                 s->init_num=0;
565                                 }
566                         break;
567
568                 case SSL3_ST_SW_SRVR_DONE_A:
569                 case SSL3_ST_SW_SRVR_DONE_B:
570                         ret=ssl3_send_server_done(s);
571                         if (ret <= 0) goto end;
572                         s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
573                         s->state=SSL3_ST_SW_FLUSH;
574                         s->init_num=0;
575                         break;
576                 
577                 case SSL3_ST_SW_FLUSH:
578
579                         /* This code originally checked to see if
580                          * any data was pending using BIO_CTRL_INFO
581                          * and then flushed. This caused problems
582                          * as documented in PR#1939. The proposed
583                          * fix doesn't completely resolve this issue
584                          * as buggy implementations of BIO_CTRL_PENDING
585                          * still exist. So instead we just flush
586                          * unconditionally.
587                          */
588
589                         s->rwstate=SSL_WRITING;
590                         if (BIO_flush(s->wbio) <= 0)
591                                 {
592                                 ret= -1;
593                                 goto end;
594                                 }
595                         s->rwstate=SSL_NOTHING;
596
597                         s->state=s->s3->tmp.next_state;
598                         break;
599 #ifndef OPENSSL_NO_TLSEXT
600                 case SSL3_ST_SR_SUPPLEMENTAL_DATA_A:
601                 case SSL3_ST_SR_SUPPLEMENTAL_DATA_B:
602                         ret=tls1_get_client_supplemental_data(s);
603                         if (ret <= 0) goto end;
604                         s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
605                         s->state=SSL3_ST_SW_FLUSH;
606                         s->init_num=0;
607                         break;
608 #endif
609                 case SSL3_ST_SR_CERT_A:
610                 case SSL3_ST_SR_CERT_B:
611                         /* Check for second client hello (MS SGC) */
612                         ret = ssl3_check_client_hello(s);
613                         if (ret <= 0)
614                                 goto end;
615                         if (ret == 2)
616                                 s->state = SSL3_ST_SR_CLNT_HELLO_C;
617 #ifndef OPENSSL_NO_TLSEXT
618                         else if (ret == 3)
619                                 s->state = SSL3_ST_SR_SUPPLEMENTAL_DATA_A;
620 #endif
621                         else {
622                                 if (s->s3->tmp.cert_request)
623                                         {
624                                         ret=ssl3_get_client_certificate(s);
625                                         if (ret <= 0) goto end;
626                                         }
627                                 s->init_num=0;
628                                 s->state=SSL3_ST_SR_KEY_EXCH_A;
629                         }
630                         break;
631
632                 case SSL3_ST_SR_KEY_EXCH_A:
633                 case SSL3_ST_SR_KEY_EXCH_B:
634                         ret=ssl3_get_client_key_exchange(s);
635                         if (ret <= 0)
636                                 goto end;
637                         if (ret == 2)
638                                 {
639                                 /* For the ECDH ciphersuites when
640                                  * the client sends its ECDH pub key in
641                                  * a certificate, the CertificateVerify
642                                  * message is not sent.
643                                  * Also for GOST ciphersuites when
644                                  * the client uses its key from the certificate
645                                  * for key exchange.
646                                  */
647 #if defined(OPENSSL_NO_TLSEXT) || defined(OPENSSL_NO_NEXTPROTONEG)
648                                 s->state=SSL3_ST_SR_FINISHED_A;
649 #else
650                                 if (s->s3->next_proto_neg_seen)
651                                         s->state=SSL3_ST_SR_NEXT_PROTO_A;
652                                 else
653                                         s->state=SSL3_ST_SR_FINISHED_A;
654 #endif
655                                 s->init_num = 0;
656                                 }
657                         else if (SSL_USE_SIGALGS(s))
658                                 {
659                                 s->state=SSL3_ST_SR_CERT_VRFY_A;
660                                 s->init_num=0;
661                                 if (!s->session->peer)
662                                         break;
663                                 /* For sigalgs freeze the handshake buffer
664                                  * at this point and digest cached records.
665                                  */
666                                 if (!s->s3->handshake_buffer)
667                                         {
668                                         SSLerr(SSL_F_SSL3_ACCEPT,ERR_R_INTERNAL_ERROR);
669                                         return -1;
670                                         }
671                                 s->s3->flags |= TLS1_FLAGS_KEEP_HANDSHAKE;
672                                 if (!ssl3_digest_cached_records(s))
673                                         return -1;
674                                 }
675                         else
676                                 {
677                                 int offset=0;
678                                 int dgst_num;
679
680                                 s->state=SSL3_ST_SR_CERT_VRFY_A;
681                                 s->init_num=0;
682
683                                 /* We need to get hashes here so if there is
684                                  * a client cert, it can be verified
685                                  * FIXME - digest processing for CertificateVerify
686                                  * should be generalized. But it is next step
687                                  */
688                                 if (s->s3->handshake_buffer)
689                                         if (!ssl3_digest_cached_records(s))
690                                                 return -1;
691                                 for (dgst_num=0; dgst_num<SSL_MAX_DIGEST;dgst_num++)    
692                                         if (s->s3->handshake_dgst[dgst_num]) 
693                                                 {
694                                                 int dgst_size;
695
696                                                 s->method->ssl3_enc->cert_verify_mac(s,EVP_MD_CTX_type(s->s3->handshake_dgst[dgst_num]),&(s->s3->tmp.cert_verify_md[offset]));
697                                                 dgst_size=EVP_MD_CTX_size(s->s3->handshake_dgst[dgst_num]);
698                                                 if (dgst_size < 0)
699                                                         {
700                                                         ret = -1;
701                                                         goto end;
702                                                         }
703                                                 offset+=dgst_size;
704                                                 }               
705                                 }
706                         break;
707
708                 case SSL3_ST_SR_CERT_VRFY_A:
709                 case SSL3_ST_SR_CERT_VRFY_B:
710
711                         s->s3->flags |= SSL3_FLAGS_CCS_OK;
712                         /* we should decide if we expected this one */
713                         ret=ssl3_get_cert_verify(s);
714                         if (ret <= 0) goto end;
715
716 #if defined(OPENSSL_NO_TLSEXT) || defined(OPENSSL_NO_NEXTPROTONEG)
717                         s->state=SSL3_ST_SR_FINISHED_A;
718 #else
719                         if (s->s3->next_proto_neg_seen)
720                                 s->state=SSL3_ST_SR_NEXT_PROTO_A;
721                         else
722                                 s->state=SSL3_ST_SR_FINISHED_A;
723 #endif
724                         s->init_num=0;
725                         break;
726
727 #if !defined(OPENSSL_NO_TLSEXT) && !defined(OPENSSL_NO_NEXTPROTONEG)
728                 case SSL3_ST_SR_NEXT_PROTO_A:
729                 case SSL3_ST_SR_NEXT_PROTO_B:
730                         ret=ssl3_get_next_proto(s);
731                         if (ret <= 0) goto end;
732                         s->init_num = 0;
733                         s->state=SSL3_ST_SR_FINISHED_A;
734                         break;
735 #endif
736
737                 case SSL3_ST_SR_FINISHED_A:
738                 case SSL3_ST_SR_FINISHED_B:
739                         s->s3->flags |= SSL3_FLAGS_CCS_OK;
740                         ret=ssl3_get_finished(s,SSL3_ST_SR_FINISHED_A,
741                                 SSL3_ST_SR_FINISHED_B);
742                         if (ret <= 0) goto end;
743                         if (s->hit)
744                                 s->state=SSL_ST_OK;
745 #ifndef OPENSSL_NO_TLSEXT
746                         else if (s->tlsext_ticket_expected)
747                                 s->state=SSL3_ST_SW_SESSION_TICKET_A;
748 #endif
749                         else
750                                 s->state=SSL3_ST_SW_CHANGE_A;
751                         s->init_num=0;
752                         break;
753
754 #ifndef OPENSSL_NO_TLSEXT
755                 case SSL3_ST_SW_SESSION_TICKET_A:
756                 case SSL3_ST_SW_SESSION_TICKET_B:
757                         ret=ssl3_send_newsession_ticket(s);
758                         if (ret <= 0) goto end;
759                         s->state=SSL3_ST_SW_CHANGE_A;
760                         s->init_num=0;
761                         break;
762
763                 case SSL3_ST_SW_CERT_STATUS_A:
764                 case SSL3_ST_SW_CERT_STATUS_B:
765                         ret=ssl3_send_cert_status(s);
766                         if (ret <= 0) goto end;
767                         s->state=SSL3_ST_SW_KEY_EXCH_A;
768                         s->init_num=0;
769                         break;
770
771 #endif
772
773                 case SSL3_ST_SW_CHANGE_A:
774                 case SSL3_ST_SW_CHANGE_B:
775
776                         s->session->cipher=s->s3->tmp.new_cipher;
777                         if (!s->method->ssl3_enc->setup_key_block(s))
778                                 { ret= -1; goto end; }
779
780                         ret=ssl3_send_change_cipher_spec(s,
781                                 SSL3_ST_SW_CHANGE_A,SSL3_ST_SW_CHANGE_B);
782
783                         if (ret <= 0) goto end;
784                         s->state=SSL3_ST_SW_FINISHED_A;
785                         s->init_num=0;
786
787                         if (!s->method->ssl3_enc->change_cipher_state(s,
788                                 SSL3_CHANGE_CIPHER_SERVER_WRITE))
789                                 {
790                                 ret= -1;
791                                 goto end;
792                                 }
793
794                         break;
795
796                 case SSL3_ST_SW_FINISHED_A:
797                 case SSL3_ST_SW_FINISHED_B:
798                         ret=ssl3_send_finished(s,
799                                 SSL3_ST_SW_FINISHED_A,SSL3_ST_SW_FINISHED_B,
800                                 s->method->ssl3_enc->server_finished_label,
801                                 s->method->ssl3_enc->server_finished_label_len);
802                         if (ret <= 0) goto end;
803                         s->state=SSL3_ST_SW_FLUSH;
804                         if (s->hit)
805                                 {
806 #if defined(OPENSSL_NO_TLSEXT) || defined(OPENSSL_NO_NEXTPROTONEG)
807                                 s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
808 #else
809                                 if (s->s3->next_proto_neg_seen)
810                                         {
811                                         s->s3->flags |= SSL3_FLAGS_CCS_OK;
812                                         s->s3->tmp.next_state=SSL3_ST_SR_NEXT_PROTO_A;
813                                         }
814                                 else
815                                         s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
816 #endif
817                                 }
818                         else
819                                 s->s3->tmp.next_state=SSL_ST_OK;
820                         s->init_num=0;
821                         break;
822
823                 case SSL_ST_OK:
824                         /* clean a few things up */
825                         ssl3_cleanup_key_block(s);
826
827                         BUF_MEM_free(s->init_buf);
828                         s->init_buf=NULL;
829
830                         /* remove buffering on output */
831                         ssl_free_wbio_buffer(s);
832
833                         s->init_num=0;
834
835                         if (s->renegotiate == 2) /* skipped if we just sent a HelloRequest */
836                                 {
837                                 s->renegotiate=0;
838                                 s->new_session=0;
839                                 
840                                 ssl_update_cache(s,SSL_SESS_CACHE_SERVER);
841                                 
842                                 s->ctx->stats.sess_accept_good++;
843                                 /* s->server=1; */
844                                 s->handshake_func=ssl3_accept;
845
846                                 if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
847                                 }
848                         
849                         ret = 1;
850                         goto end;
851                         /* break; */
852
853                 default:
854                         SSLerr(SSL_F_SSL3_ACCEPT,SSL_R_UNKNOWN_STATE);
855                         ret= -1;
856                         goto end;
857                         /* break; */
858                         }
859                 
860                 if (!s->s3->tmp.reuse_message && !skip)
861                         {
862                         if (s->debug)
863                                 {
864                                 if ((ret=BIO_flush(s->wbio)) <= 0)
865                                         goto end;
866                                 }
867
868
869                         if ((cb != NULL) && (s->state != state))
870                                 {
871                                 new_state=s->state;
872                                 s->state=state;
873                                 cb(s,SSL_CB_ACCEPT_LOOP,1);
874                                 s->state=new_state;
875                                 }
876                         }
877                 skip=0;
878                 }
879 end:
880         /* BIO_flush(s->wbio); */
881
882         s->in_handshake--;
883         if (cb != NULL)
884                 cb(s,SSL_CB_ACCEPT_EXIT,ret);
885         return(ret);
886         }
887
888 int ssl3_send_hello_request(SSL *s)
889         {
890
891         if (s->state == SSL3_ST_SW_HELLO_REQ_A)
892                 {
893                 ssl_set_handshake_header(s, SSL3_MT_HELLO_REQUEST, 0);
894                 s->state=SSL3_ST_SW_HELLO_REQ_B;
895                 }
896
897         /* SSL3_ST_SW_HELLO_REQ_B */
898         return ssl_do_write(s);
899         }
900
901 int ssl3_check_client_hello(SSL *s)
902         {
903         int ok;
904         long n;
905
906         /* this function is called when we really expect a Certificate message,
907          * so permit appropriate message length */
908         n=s->method->ssl_get_message(s,
909                 SSL3_ST_SR_CERT_A,
910                 SSL3_ST_SR_CERT_B,
911                 -1,
912                 s->max_cert_list,
913                 &ok);
914         if (!ok) return((int)n);
915         s->s3->tmp.reuse_message = 1;
916 #ifndef OPENSSL_NO_TLSEXT
917         if (s->s3->tmp.message_type == SSL3_MT_SUPPLEMENTAL_DATA)
918                 return 3;
919 #endif
920         if (s->s3->tmp.message_type == SSL3_MT_CLIENT_HELLO)
921                 {
922                 /* We only allow the client to restart the handshake once per
923                  * negotiation. */
924                 if (s->s3->flags & SSL3_FLAGS_SGC_RESTART_DONE)
925                         {
926                         SSLerr(SSL_F_SSL3_CHECK_CLIENT_HELLO, SSL_R_MULTIPLE_SGC_RESTARTS);
927                         return -1;
928                         }
929                 /* Throw away what we have done so far in the current handshake,
930                  * which will now be aborted. (A full SSL_clear would be too much.) */
931 #ifndef OPENSSL_NO_DH
932                 if (s->s3->tmp.dh != NULL)
933                         {
934                         DH_free(s->s3->tmp.dh);
935                         s->s3->tmp.dh = NULL;
936                         }
937 #endif
938 #ifndef OPENSSL_NO_ECDH
939                 if (s->s3->tmp.ecdh != NULL)
940                         {
941                         EC_KEY_free(s->s3->tmp.ecdh);
942                         s->s3->tmp.ecdh = NULL;
943                         }
944 #endif
945                 s->s3->flags |= SSL3_FLAGS_SGC_RESTART_DONE;
946                 return 2;
947                 }
948         return 1;
949 }
950
951 int ssl3_get_client_hello(SSL *s)
952         {
953         int i,j,ok,al=SSL_AD_INTERNAL_ERROR,ret= -1;
954         unsigned int cookie_len;
955         long n;
956         unsigned long id;
957         unsigned char *p,*d;
958         SSL_CIPHER *c;
959 #ifndef OPENSSL_NO_COMP
960         unsigned char *q;
961         SSL_COMP *comp=NULL;
962 #endif
963         STACK_OF(SSL_CIPHER) *ciphers=NULL;
964
965         if (s->state == SSL3_ST_SR_CLNT_HELLO_C && !s->first_packet)
966                 goto retry_cert;
967
968         /* We do this so that we will respond with our native type.
969          * If we are TLSv1 and we get SSLv3, we will respond with TLSv1,
970          * This down switching should be handled by a different method.
971          * If we are SSLv3, we will respond with SSLv3, even if prompted with
972          * TLSv1.
973          */
974         if (s->state == SSL3_ST_SR_CLNT_HELLO_A
975                 )
976                 {
977                 s->state=SSL3_ST_SR_CLNT_HELLO_B;
978                 }
979         s->first_packet=1;
980         n=s->method->ssl_get_message(s,
981                 SSL3_ST_SR_CLNT_HELLO_B,
982                 SSL3_ST_SR_CLNT_HELLO_C,
983                 SSL3_MT_CLIENT_HELLO,
984                 SSL3_RT_MAX_PLAIN_LENGTH,
985                 &ok);
986
987         if (!ok) return((int)n);
988         s->first_packet=0;
989         d=p=(unsigned char *)s->init_msg;
990
991         /* use version from inside client hello, not from record header
992          * (may differ: see RFC 2246, Appendix E, second paragraph) */
993         s->client_version=(((int)p[0])<<8)|(int)p[1];
994         p+=2;
995
996         if (SSL_IS_DTLS(s)  ?   (s->client_version > s->version &&
997                                  s->method->version != DTLS_ANY_VERSION)
998                             :   (s->client_version < s->version))
999                 {
1000                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_WRONG_VERSION_NUMBER);
1001                 if ((s->client_version>>8) == SSL3_VERSION_MAJOR &&
1002                         !s->enc_write_ctx && !s->write_hash)
1003                         {
1004                         /* similar to ssl3_get_record, send alert using remote version number */
1005                         s->version = s->client_version;
1006                         }
1007                 al = SSL_AD_PROTOCOL_VERSION;
1008                 goto f_err;
1009                 }
1010
1011         /* If we require cookies and this ClientHello doesn't
1012          * contain one, just return since we do not want to
1013          * allocate any memory yet. So check cookie length...
1014          */
1015         if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE)
1016                 {
1017                 unsigned int session_length, cookie_length;
1018                 
1019                 session_length = *(p + SSL3_RANDOM_SIZE);
1020                 cookie_length = *(p + SSL3_RANDOM_SIZE + session_length + 1);
1021
1022                 if (cookie_length == 0)
1023                         return 1;
1024                 }
1025
1026         /* load the client random */
1027         memcpy(s->s3->client_random,p,SSL3_RANDOM_SIZE);
1028         p+=SSL3_RANDOM_SIZE;
1029
1030         /* get the session-id */
1031         j= *(p++);
1032
1033         s->hit=0;
1034         /* Versions before 0.9.7 always allow clients to resume sessions in renegotiation.
1035          * 0.9.7 and later allow this by default, but optionally ignore resumption requests
1036          * with flag SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION (it's a new flag rather
1037          * than a change to default behavior so that applications relying on this for security
1038          * won't even compile against older library versions).
1039          *
1040          * 1.0.1 and later also have a function SSL_renegotiate_abbreviated() to request
1041          * renegotiation but not a new session (s->new_session remains unset): for servers,
1042          * this essentially just means that the SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION
1043          * setting will be ignored.
1044          */
1045         if ((s->new_session && (s->options & SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION)))
1046                 {
1047                 if (!ssl_get_new_session(s,1))
1048                         goto err;
1049                 }
1050         else
1051                 {
1052                 i=ssl_get_prev_session(s, p, j, d + n);
1053                 if (i == 1)
1054                         { /* previous session */
1055                         s->hit=1;
1056                         }
1057                 else if (i == -1)
1058                         goto err;
1059                 else /* i == 0 */
1060                         {
1061                         if (!ssl_get_new_session(s,1))
1062                                 goto err;
1063                         }
1064                 }
1065
1066         p+=j;
1067
1068         if (SSL_IS_DTLS(s))
1069                 {
1070                 /* cookie stuff */
1071                 cookie_len = *(p++);
1072
1073                 /* 
1074                  * The ClientHello may contain a cookie even if the
1075                  * HelloVerify message has not been sent--make sure that it
1076                  * does not cause an overflow.
1077                  */
1078                 if ( cookie_len > sizeof(s->d1->rcvd_cookie))
1079                         {
1080                         /* too much data */
1081                         al = SSL_AD_DECODE_ERROR;
1082                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_COOKIE_MISMATCH);
1083                         goto f_err;
1084                         }
1085
1086                 /* verify the cookie if appropriate option is set. */
1087                 if ((SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) &&
1088                         cookie_len > 0)
1089                         {
1090                         memcpy(s->d1->rcvd_cookie, p, cookie_len);
1091
1092                         if ( s->ctx->app_verify_cookie_cb != NULL)
1093                                 {
1094                                 if ( s->ctx->app_verify_cookie_cb(s, s->d1->rcvd_cookie,
1095                                         cookie_len) == 0)
1096                                         {
1097                                         al=SSL_AD_HANDSHAKE_FAILURE;
1098                                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, 
1099                                                 SSL_R_COOKIE_MISMATCH);
1100                                         goto f_err;
1101                                         }
1102                                 /* else cookie verification succeeded */
1103                                 }
1104                         else if ( memcmp(s->d1->rcvd_cookie, s->d1->cookie, 
1105                                                   s->d1->cookie_len) != 0) /* default verification */
1106                                 {
1107                                         al=SSL_AD_HANDSHAKE_FAILURE;
1108                                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, 
1109                                                 SSL_R_COOKIE_MISMATCH);
1110                                         goto f_err;
1111                                 }
1112                         /* Set to -2 so if successful we return 2 */
1113                         ret = -2;
1114                         }
1115
1116                 p += cookie_len;
1117                 if (s->method->version == DTLS_ANY_VERSION)
1118                         {
1119                         /* Select version to use */
1120                         if (s->client_version <= DTLS1_2_VERSION &&
1121                                 !(s->options & SSL_OP_NO_DTLSv1_2))
1122                                 {
1123                                 s->version = DTLS1_2_VERSION;
1124                                 s->method = DTLSv1_2_server_method();
1125                                 }
1126                         else if (tls1_suiteb(s))
1127                                 {
1128                                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_ONLY_DTLS_1_2_ALLOWED_IN_SUITEB_MODE);
1129                                 s->version = s->client_version;
1130                                 al = SSL_AD_PROTOCOL_VERSION;
1131                                 goto f_err;
1132                                 }
1133                         else if (s->client_version <= DTLS1_VERSION &&
1134                                 !(s->options & SSL_OP_NO_DTLSv1))
1135                                 {
1136                                 s->version = DTLS1_VERSION;
1137                                 s->method = DTLSv1_server_method();
1138                                 }
1139                         else
1140                                 {
1141                                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_WRONG_VERSION_NUMBER);
1142                                 s->version = s->client_version;
1143                                 al = SSL_AD_PROTOCOL_VERSION;
1144                                 goto f_err;
1145                                 }
1146                         s->session->ssl_version = s->version;
1147                         }
1148                 }
1149
1150         n2s(p,i);
1151         if ((i == 0) && (j != 0))
1152                 {
1153                 /* we need a cipher if we are not resuming a session */
1154                 al=SSL_AD_ILLEGAL_PARAMETER;
1155                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_NO_CIPHERS_SPECIFIED);
1156                 goto f_err;
1157                 }
1158         if ((p+i) >= (d+n))
1159                 {
1160                 /* not enough data */
1161                 al=SSL_AD_DECODE_ERROR;
1162                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_LENGTH_MISMATCH);
1163                 goto f_err;
1164                 }
1165         if ((i > 0) && (ssl_bytes_to_cipher_list(s,p,i,&(ciphers))
1166                 == NULL))
1167                 {
1168                 goto err;
1169                 }
1170         p+=i;
1171
1172         /* If it is a hit, check that the cipher is in the list */
1173         if ((s->hit) && (i > 0))
1174                 {
1175                 j=0;
1176                 id=s->session->cipher->id;
1177
1178 #ifdef CIPHER_DEBUG
1179                 printf("client sent %d ciphers\n",sk_num(ciphers));
1180 #endif
1181                 for (i=0; i<sk_SSL_CIPHER_num(ciphers); i++)
1182                         {
1183                         c=sk_SSL_CIPHER_value(ciphers,i);
1184 #ifdef CIPHER_DEBUG
1185                         printf("client [%2d of %2d]:%s\n",
1186                                 i,sk_num(ciphers),SSL_CIPHER_get_name(c));
1187 #endif
1188                         if (c->id == id)
1189                                 {
1190                                 j=1;
1191                                 break;
1192                                 }
1193                         }
1194 /* Disabled because it can be used in a ciphersuite downgrade
1195  * attack: CVE-2010-4180.
1196  */
1197 #if 0
1198                 if (j == 0 && (s->options & SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG) && (sk_SSL_CIPHER_num(ciphers) == 1))
1199                         {
1200                         /* Special case as client bug workaround: the previously used cipher may
1201                          * not be in the current list, the client instead might be trying to
1202                          * continue using a cipher that before wasn't chosen due to server
1203                          * preferences.  We'll have to reject the connection if the cipher is not
1204                          * enabled, though. */
1205                         c = sk_SSL_CIPHER_value(ciphers, 0);
1206                         if (sk_SSL_CIPHER_find(SSL_get_ciphers(s), c) >= 0)
1207                                 {
1208                                 s->session->cipher = c;
1209                                 j = 1;
1210                                 }
1211                         }
1212 #endif
1213                 if (j == 0)
1214                         {
1215                         /* we need to have the cipher in the cipher
1216                          * list if we are asked to reuse it */
1217                         al=SSL_AD_ILLEGAL_PARAMETER;
1218                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_REQUIRED_CIPHER_MISSING);
1219                         goto f_err;
1220                         }
1221                 }
1222
1223         /* compression */
1224         i= *(p++);
1225         if ((p+i) > (d+n))
1226                 {
1227                 /* not enough data */
1228                 al=SSL_AD_DECODE_ERROR;
1229                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_LENGTH_MISMATCH);
1230                 goto f_err;
1231                 }
1232 #ifndef OPENSSL_NO_COMP
1233         q=p;
1234 #endif
1235         for (j=0; j<i; j++)
1236                 {
1237                 if (p[j] == 0) break;
1238                 }
1239
1240         p+=i;
1241         if (j >= i)
1242                 {
1243                 /* no compress */
1244                 al=SSL_AD_DECODE_ERROR;
1245                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_NO_COMPRESSION_SPECIFIED);
1246                 goto f_err;
1247                 }
1248
1249 #ifndef OPENSSL_NO_TLSEXT
1250         /* TLS extensions*/
1251         if (s->version >= SSL3_VERSION)
1252                 {
1253                 if (!ssl_parse_clienthello_tlsext(s,&p,d,n))
1254                         {
1255                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_PARSE_TLSEXT);
1256                         goto err;
1257                         }
1258                 }
1259
1260         /* Check if we want to use external pre-shared secret for this
1261          * handshake for not reused session only. We need to generate
1262          * server_random before calling tls_session_secret_cb in order to allow
1263          * SessionTicket processing to use it in key derivation. */
1264         {
1265                 unsigned char *pos;
1266                 pos=s->s3->server_random;
1267                 if (ssl_fill_hello_random(s, 1, pos, SSL3_RANDOM_SIZE) <= 0)
1268                         {
1269                         goto f_err;
1270                         }
1271         }
1272
1273         if (!s->hit && s->version >= TLS1_VERSION && s->tls_session_secret_cb)
1274                 {
1275                 SSL_CIPHER *pref_cipher=NULL;
1276
1277                 s->session->master_key_length=sizeof(s->session->master_key);
1278                 if(s->tls_session_secret_cb(s, s->session->master_key, &s->session->master_key_length,
1279                         ciphers, &pref_cipher, s->tls_session_secret_cb_arg))
1280                         {
1281                         s->hit=1;
1282                         s->session->ciphers=ciphers;
1283                         s->session->verify_result=X509_V_OK;
1284
1285                         ciphers=NULL;
1286
1287                         /* check if some cipher was preferred by call back */
1288                         pref_cipher=pref_cipher ? pref_cipher : ssl3_choose_cipher(s, s->session->ciphers, SSL_get_ciphers(s));
1289                         if (pref_cipher == NULL)
1290                                 {
1291                                 al=SSL_AD_HANDSHAKE_FAILURE;
1292                                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_NO_SHARED_CIPHER);
1293                                 goto f_err;
1294                                 }
1295
1296                         s->session->cipher=pref_cipher;
1297
1298                         if (s->cipher_list)
1299                                 sk_SSL_CIPHER_free(s->cipher_list);
1300
1301                         if (s->cipher_list_by_id)
1302                                 sk_SSL_CIPHER_free(s->cipher_list_by_id);
1303
1304                         s->cipher_list = sk_SSL_CIPHER_dup(s->session->ciphers);
1305                         s->cipher_list_by_id = sk_SSL_CIPHER_dup(s->session->ciphers);
1306                         }
1307                 }
1308 #endif
1309
1310         /* Worst case, we will use the NULL compression, but if we have other
1311          * options, we will now look for them.  We have i-1 compression
1312          * algorithms from the client, starting at q. */
1313         s->s3->tmp.new_compression=NULL;
1314 #ifndef OPENSSL_NO_COMP
1315         /* This only happens if we have a cache hit */
1316         if (s->session->compress_meth != 0)
1317                 {
1318                 int m, comp_id = s->session->compress_meth;
1319                 /* Perform sanity checks on resumed compression algorithm */
1320                 /* Can't disable compression */
1321                 if (!ssl_allow_compression(s))
1322                         {
1323                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_INCONSISTENT_COMPRESSION);
1324                         goto f_err;
1325                         }
1326                 /* Look for resumed compression method */
1327                 for (m = 0; m < sk_SSL_COMP_num(s->ctx->comp_methods); m++)
1328                         {
1329                         comp=sk_SSL_COMP_value(s->ctx->comp_methods,m);
1330                         if (comp_id == comp->id)
1331                                 {
1332                                 s->s3->tmp.new_compression=comp;
1333                                 break;
1334                                 }
1335                         }
1336                 if (s->s3->tmp.new_compression == NULL)
1337                         {
1338                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_INVALID_COMPRESSION_ALGORITHM);
1339                         goto f_err;
1340                         }
1341                 /* Look for resumed method in compression list */
1342                 for (m = 0; m < i; m++)
1343                         {
1344                         if (q[m] == comp_id)
1345                                 break;
1346                         }
1347                 if (m >= i)
1348                         {
1349                         al=SSL_AD_ILLEGAL_PARAMETER;
1350                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_REQUIRED_COMPRESSSION_ALGORITHM_MISSING);
1351                         goto f_err;
1352                         }
1353                 }
1354         else if (s->hit)
1355                 comp = NULL;
1356         else if (ssl_allow_compression(s) && s->ctx->comp_methods)
1357                 { /* See if we have a match */
1358                 int m,nn,o,v,done=0;
1359
1360                 nn=sk_SSL_COMP_num(s->ctx->comp_methods);
1361                 for (m=0; m<nn; m++)
1362                         {
1363                         comp=sk_SSL_COMP_value(s->ctx->comp_methods,m);
1364                         v=comp->id;
1365                         for (o=0; o<i; o++)
1366                                 {
1367                                 if (v == q[o])
1368                                         {
1369                                         done=1;
1370                                         break;
1371                                         }
1372                                 }
1373                         if (done) break;
1374                         }
1375                 if (done)
1376                         s->s3->tmp.new_compression=comp;
1377                 else
1378                         comp=NULL;
1379                 }
1380 #else
1381         /* If compression is disabled we'd better not try to resume a session
1382          * using compression.
1383          */
1384         if (s->session->compress_meth != 0)
1385                 {
1386                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_INCONSISTENT_COMPRESSION);
1387                 goto f_err;
1388                 }
1389 #endif
1390
1391         /* Given s->session->ciphers and SSL_get_ciphers, we must
1392          * pick a cipher */
1393
1394         if (!s->hit)
1395                 {
1396 #ifdef OPENSSL_NO_COMP
1397                 s->session->compress_meth=0;
1398 #else
1399                 s->session->compress_meth=(comp == NULL)?0:comp->id;
1400 #endif
1401                 if (s->session->ciphers != NULL)
1402                         sk_SSL_CIPHER_free(s->session->ciphers);
1403                 s->session->ciphers=ciphers;
1404                 if (ciphers == NULL)
1405                         {
1406                         al=SSL_AD_ILLEGAL_PARAMETER;
1407                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_NO_CIPHERS_PASSED);
1408                         goto f_err;
1409                         }
1410                 ciphers=NULL;
1411                 /* Let cert callback update server certificates if required */
1412                 retry_cert:             
1413                 if (s->cert->cert_cb)
1414                         {
1415                         int rv = s->cert->cert_cb(s, s->cert->cert_cb_arg);
1416                         if (rv == 0)
1417                                 {
1418                                 al=SSL_AD_INTERNAL_ERROR;
1419                                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_CERT_CB_ERROR);
1420                                 goto f_err;
1421                                 }
1422                         if (rv < 0)
1423                                 {
1424                                 s->rwstate=SSL_X509_LOOKUP;
1425                                 return -1;
1426                                 }
1427                         s->rwstate = SSL_NOTHING;
1428                         }
1429                 c=ssl3_choose_cipher(s,s->session->ciphers,
1430                                      SSL_get_ciphers(s));
1431
1432                 if (c == NULL)
1433                         {
1434                         al=SSL_AD_HANDSHAKE_FAILURE;
1435                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_NO_SHARED_CIPHER);
1436                         goto f_err;
1437                         }
1438                 s->s3->tmp.new_cipher=c;
1439                 /* check whether we should disable session resumption */
1440                 if (s->not_resumable_session_cb != NULL)
1441                         s->session->not_resumable=s->not_resumable_session_cb(s,
1442                                 ((c->algorithm_mkey & (SSL_kDHE | SSL_kECDHE)) != 0));
1443                 if (s->session->not_resumable)
1444                         /* do not send a session ticket */
1445                         s->tlsext_ticket_expected = 0;
1446                 }
1447         else
1448                 {
1449                 /* Session-id reuse */
1450 #ifdef REUSE_CIPHER_BUG
1451                 STACK_OF(SSL_CIPHER) *sk;
1452                 SSL_CIPHER *nc=NULL;
1453                 SSL_CIPHER *ec=NULL;
1454
1455                 if (s->options & SSL_OP_NETSCAPE_DEMO_CIPHER_CHANGE_BUG)
1456                         {
1457                         sk=s->session->ciphers;
1458                         for (i=0; i<sk_SSL_CIPHER_num(sk); i++)
1459                                 {
1460                                 c=sk_SSL_CIPHER_value(sk,i);
1461                                 if (c->algorithm_enc & SSL_eNULL)
1462                                         nc=c;
1463                                 if (SSL_C_IS_EXPORT(c))
1464                                         ec=c;
1465                                 }
1466                         if (nc != NULL)
1467                                 s->s3->tmp.new_cipher=nc;
1468                         else if (ec != NULL)
1469                                 s->s3->tmp.new_cipher=ec;
1470                         else
1471                                 s->s3->tmp.new_cipher=s->session->cipher;
1472                         }
1473                 else
1474 #endif
1475                 s->s3->tmp.new_cipher=s->session->cipher;
1476                 }
1477
1478         if (!SSL_USE_SIGALGS(s) || !(s->verify_mode & SSL_VERIFY_PEER))
1479                 {
1480                 if (!ssl3_digest_cached_records(s))
1481                         goto f_err;
1482                 }
1483         
1484         /* we now have the following setup. 
1485          * client_random
1486          * cipher_list          - our prefered list of ciphers
1487          * ciphers              - the clients prefered list of ciphers
1488          * compression          - basically ignored right now
1489          * ssl version is set   - sslv3
1490          * s->session           - The ssl session has been setup.
1491          * s->hit               - session reuse flag
1492          * s->s3->tmp.new_cipher- the new cipher to use.
1493          */
1494
1495         /* Handles TLS extensions that we couldn't check earlier */
1496         if (s->version >= SSL3_VERSION)
1497                 {
1498                 if (ssl_check_clienthello_tlsext_late(s) <= 0)
1499                         {
1500                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_CLIENTHELLO_TLSEXT);
1501                         goto err;
1502                         }
1503                 }
1504
1505         if (ret < 0) ret=-ret;
1506         if (0)
1507                 {
1508 f_err:
1509                 ssl3_send_alert(s,SSL3_AL_FATAL,al);
1510                 }
1511 err:
1512         if (ciphers != NULL) sk_SSL_CIPHER_free(ciphers);
1513         return ret < 0 ? -1 : ret;
1514         }
1515
1516 int ssl3_send_server_hello(SSL *s)
1517         {
1518         unsigned char *buf;
1519         unsigned char *p,*d;
1520         int i,sl;
1521         int al = 0;
1522         unsigned long l;
1523
1524         if (s->state == SSL3_ST_SW_SRVR_HELLO_A)
1525                 {
1526                 buf=(unsigned char *)s->init_buf->data;
1527 #ifdef OPENSSL_NO_TLSEXT
1528                 p=s->s3->server_random;
1529                 if (ssl_fill_hello_random(s, 1, p, SSL3_RANDOM_SIZE) <= 0)
1530                         return -1;
1531 #endif
1532                 /* Do the message type and length last */
1533                 d=p= ssl_handshake_start(s);
1534
1535                 *(p++)=s->version>>8;
1536                 *(p++)=s->version&0xff;
1537
1538                 /* Random stuff */
1539                 memcpy(p,s->s3->server_random,SSL3_RANDOM_SIZE);
1540                 p+=SSL3_RANDOM_SIZE;
1541
1542                 /* There are several cases for the session ID to send
1543                  * back in the server hello:
1544                  * - For session reuse from the session cache,
1545                  *   we send back the old session ID.
1546                  * - If stateless session reuse (using a session ticket)
1547                  *   is successful, we send back the client's "session ID"
1548                  *   (which doesn't actually identify the session).
1549                  * - If it is a new session, we send back the new
1550                  *   session ID.
1551                  * - However, if we want the new session to be single-use,
1552                  *   we send back a 0-length session ID.
1553                  * s->hit is non-zero in either case of session reuse,
1554                  * so the following won't overwrite an ID that we're supposed
1555                  * to send back.
1556                  */
1557                 if (s->session->not_resumable ||
1558                         (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER)
1559                                 && !s->hit))
1560                         s->session->session_id_length=0;
1561
1562                 sl=s->session->session_id_length;
1563                 if (sl > (int)sizeof(s->session->session_id))
1564                         {
1565                         SSLerr(SSL_F_SSL3_SEND_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
1566                         return -1;
1567                         }
1568                 *(p++)=sl;
1569                 memcpy(p,s->session->session_id,sl);
1570                 p+=sl;
1571
1572                 /* put the cipher */
1573                 i=ssl3_put_cipher_by_char(s->s3->tmp.new_cipher,p);
1574                 p+=i;
1575
1576                 /* put the compression method */
1577 #ifdef OPENSSL_NO_COMP
1578                         *(p++)=0;
1579 #else
1580                 if (s->s3->tmp.new_compression == NULL)
1581                         *(p++)=0;
1582                 else
1583                         *(p++)=s->s3->tmp.new_compression->id;
1584 #endif
1585 #ifndef OPENSSL_NO_TLSEXT
1586                 if (ssl_prepare_serverhello_tlsext(s) <= 0)
1587                         {
1588                         SSLerr(SSL_F_SSL3_SEND_SERVER_HELLO,SSL_R_SERVERHELLO_TLSEXT);
1589                         return -1;
1590                         }
1591                 if ((p = ssl_add_serverhello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH, &al)) == NULL)
1592                         {
1593                         ssl3_send_alert(s, SSL3_AL_FATAL, al);
1594                         SSLerr(SSL_F_SSL3_SEND_SERVER_HELLO,ERR_R_INTERNAL_ERROR);
1595                         return -1;
1596                         }
1597 #endif
1598                 /* do the header */
1599                 l=(p-d);
1600                 ssl_set_handshake_header(s, SSL3_MT_SERVER_HELLO, l);
1601                 s->state=SSL3_ST_SW_SRVR_HELLO_B;
1602                 }
1603
1604         /* SSL3_ST_SW_SRVR_HELLO_B */
1605         return ssl_do_write(s);
1606         }
1607
1608 int ssl3_send_server_done(SSL *s)
1609         {
1610
1611         if (s->state == SSL3_ST_SW_SRVR_DONE_A)
1612                 {
1613                 ssl_set_handshake_header(s, SSL3_MT_SERVER_DONE, 0);
1614                 s->state = SSL3_ST_SW_SRVR_DONE_B;
1615                 }
1616
1617         /* SSL3_ST_SW_SRVR_DONE_B */
1618         return ssl_do_write(s);
1619         }
1620
1621 int ssl3_send_server_key_exchange(SSL *s)
1622         {
1623 #ifndef OPENSSL_NO_RSA
1624         unsigned char *q;
1625         int j,num;
1626         RSA *rsa;
1627         unsigned char md_buf[MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH];
1628         unsigned int u;
1629 #endif
1630 #ifndef OPENSSL_NO_DH
1631         DH *dh=NULL,*dhp;
1632 #endif
1633 #ifndef OPENSSL_NO_ECDH
1634         EC_KEY *ecdh=NULL, *ecdhp;
1635         unsigned char *encodedPoint = NULL;
1636         int encodedlen = 0;
1637         int curve_id = 0;
1638         BN_CTX *bn_ctx = NULL; 
1639 #endif
1640         EVP_PKEY *pkey;
1641         const EVP_MD *md = NULL;
1642         unsigned char *p,*d;
1643         int al,i;
1644         unsigned long type;
1645         int n;
1646         CERT *cert;
1647         BIGNUM *r[4];
1648         int nr[4],kn;
1649         BUF_MEM *buf;
1650         EVP_MD_CTX md_ctx;
1651
1652         EVP_MD_CTX_init(&md_ctx);
1653         if (s->state == SSL3_ST_SW_KEY_EXCH_A)
1654                 {
1655                 type=s->s3->tmp.new_cipher->algorithm_mkey;
1656                 cert=s->cert;
1657
1658                 buf=s->init_buf;
1659
1660                 r[0]=r[1]=r[2]=r[3]=NULL;
1661                 n=0;
1662 #ifndef OPENSSL_NO_RSA
1663                 if (type & SSL_kRSA)
1664                         {
1665                         rsa=cert->rsa_tmp;
1666                         if ((rsa == NULL) && (s->cert->rsa_tmp_cb != NULL))
1667                                 {
1668                                 rsa=s->cert->rsa_tmp_cb(s,
1669                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
1670                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
1671                                 if(rsa == NULL)
1672                                 {
1673                                         al=SSL_AD_HANDSHAKE_FAILURE;
1674                                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_ERROR_GENERATING_TMP_RSA_KEY);
1675                                         goto f_err;
1676                                 }
1677                                 RSA_up_ref(rsa);
1678                                 cert->rsa_tmp=rsa;
1679                                 }
1680                         if (rsa == NULL)
1681                                 {
1682                                 al=SSL_AD_HANDSHAKE_FAILURE;
1683                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_RSA_KEY);
1684                                 goto f_err;
1685                                 }
1686                         r[0]=rsa->n;
1687                         r[1]=rsa->e;
1688                         s->s3->tmp.use_rsa_tmp=1;
1689                         }
1690                 else
1691 #endif
1692 #ifndef OPENSSL_NO_DH
1693                         if (type & SSL_kDHE)
1694                         {
1695                         if (s->cert->dh_tmp_auto)
1696                                 {
1697                                 dhp = ssl_get_auto_dh(s);
1698                                 if (dhp == NULL)
1699                                         {
1700                                         al=SSL_AD_INTERNAL_ERROR;
1701                                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_INTERNAL_ERROR);
1702                                         goto f_err;
1703                                         }
1704                                 }
1705                         else
1706                                 dhp=cert->dh_tmp;
1707                         if ((dhp == NULL) && (s->cert->dh_tmp_cb != NULL))
1708                                 dhp=s->cert->dh_tmp_cb(s,
1709                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
1710                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
1711                         if (dhp == NULL)
1712                                 {
1713                                 al=SSL_AD_HANDSHAKE_FAILURE;
1714                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
1715                                 goto f_err;
1716                                 }
1717                         if (!ssl_security(s, SSL_SECOP_TMP_DH,
1718                                                 DH_security_bits(dhp), 0, dhp))
1719                                 {
1720                                 al=SSL_AD_HANDSHAKE_FAILURE;
1721                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_DH_KEY_TOO_SMALL);
1722                                 goto f_err;
1723                                 }
1724                         if (s->s3->tmp.dh != NULL)
1725                                 {
1726                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
1727                                 goto err;
1728                                 }
1729
1730                         if (s->cert->dh_tmp_auto)
1731                                 dh = dhp;
1732                         else if ((dh=DHparams_dup(dhp)) == NULL)
1733                                 {
1734                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
1735                                 goto err;
1736                                 }
1737
1738                         s->s3->tmp.dh=dh;
1739                         if ((dhp->pub_key == NULL ||
1740                              dhp->priv_key == NULL ||
1741                              (s->options & SSL_OP_SINGLE_DH_USE)))
1742                                 {
1743                                 if(!DH_generate_key(dh))
1744                                     {
1745                                     SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,
1746                                            ERR_R_DH_LIB);
1747                                     goto err;
1748                                     }
1749                                 }
1750                         else
1751                                 {
1752                                 dh->pub_key=BN_dup(dhp->pub_key);
1753                                 dh->priv_key=BN_dup(dhp->priv_key);
1754                                 if ((dh->pub_key == NULL) ||
1755                                         (dh->priv_key == NULL))
1756                                         {
1757                                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
1758                                         goto err;
1759                                         }
1760                                 }
1761                         r[0]=dh->p;
1762                         r[1]=dh->g;
1763                         r[2]=dh->pub_key;
1764                         }
1765                 else 
1766 #endif
1767 #ifndef OPENSSL_NO_ECDH
1768                         if (type & SSL_kECDHE)
1769                         {
1770                         const EC_GROUP *group;
1771
1772                         ecdhp=cert->ecdh_tmp;
1773                         if (s->cert->ecdh_tmp_auto)
1774                                 {
1775                                 /* Get NID of appropriate shared curve */
1776                                 int nid = tls1_shared_curve(s, -2);
1777                                 if (nid != NID_undef)
1778                                         ecdhp = EC_KEY_new_by_curve_name(nid);
1779                                 }
1780                         else if ((ecdhp == NULL) && s->cert->ecdh_tmp_cb)
1781                                 {
1782                                 ecdhp=s->cert->ecdh_tmp_cb(s,
1783                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
1784                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
1785                                 }
1786                         if (ecdhp == NULL)
1787                                 {
1788                                 al=SSL_AD_HANDSHAKE_FAILURE;
1789                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_ECDH_KEY);
1790                                 goto f_err;
1791                                 }
1792
1793                         if (s->s3->tmp.ecdh != NULL)
1794                                 {
1795                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
1796                                 goto err;
1797                                 }
1798
1799                         /* Duplicate the ECDH structure. */
1800                         if (ecdhp == NULL)
1801                                 {
1802                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
1803                                 goto err;
1804                                 }
1805                         if (s->cert->ecdh_tmp_auto)
1806                                 ecdh = ecdhp;
1807                         else if ((ecdh = EC_KEY_dup(ecdhp)) == NULL)
1808                                 {
1809                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
1810                                 goto err;
1811                                 }
1812
1813                         s->s3->tmp.ecdh=ecdh;
1814                         if ((EC_KEY_get0_public_key(ecdh) == NULL) ||
1815                             (EC_KEY_get0_private_key(ecdh) == NULL) ||
1816                             (s->options & SSL_OP_SINGLE_ECDH_USE))
1817                                 {
1818                                 if(!EC_KEY_generate_key(ecdh))
1819                                     {
1820                                     SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
1821                                     goto err;
1822                                     }
1823                                 }
1824
1825                         if (((group = EC_KEY_get0_group(ecdh)) == NULL) ||
1826                             (EC_KEY_get0_public_key(ecdh)  == NULL) ||
1827                             (EC_KEY_get0_private_key(ecdh) == NULL))
1828                                 {
1829                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
1830                                 goto err;
1831                                 }
1832
1833                         if (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher) &&
1834                             (EC_GROUP_get_degree(group) > 163)) 
1835                                 {
1836                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_ECGROUP_TOO_LARGE_FOR_CIPHER);
1837                                 goto err;
1838                                 }
1839
1840                         /* XXX: For now, we only support ephemeral ECDH
1841                          * keys over named (not generic) curves. For 
1842                          * supported named curves, curve_id is non-zero.
1843                          */
1844                         if ((curve_id = 
1845                             tls1_ec_nid2curve_id(EC_GROUP_get_curve_name(group)))
1846                             == 0)
1847                                 {
1848                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNSUPPORTED_ELLIPTIC_CURVE);
1849                                 goto err;
1850                                 }
1851
1852                         /* Encode the public key.
1853                          * First check the size of encoding and
1854                          * allocate memory accordingly.
1855                          */
1856                         encodedlen = EC_POINT_point2oct(group, 
1857                             EC_KEY_get0_public_key(ecdh),
1858                             POINT_CONVERSION_UNCOMPRESSED, 
1859                             NULL, 0, NULL);
1860
1861                         encodedPoint = (unsigned char *) 
1862                             OPENSSL_malloc(encodedlen*sizeof(unsigned char)); 
1863                         bn_ctx = BN_CTX_new();
1864                         if ((encodedPoint == NULL) || (bn_ctx == NULL))
1865                                 {
1866                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_MALLOC_FAILURE);
1867                                 goto err;
1868                                 }
1869
1870
1871                         encodedlen = EC_POINT_point2oct(group, 
1872                             EC_KEY_get0_public_key(ecdh), 
1873                             POINT_CONVERSION_UNCOMPRESSED, 
1874                             encodedPoint, encodedlen, bn_ctx);
1875
1876                         if (encodedlen == 0) 
1877                                 {
1878                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
1879                                 goto err;
1880                                 }
1881
1882                         BN_CTX_free(bn_ctx);  bn_ctx=NULL;
1883
1884                         /* XXX: For now, we only support named (not 
1885                          * generic) curves in ECDH ephemeral key exchanges.
1886                          * In this situation, we need four additional bytes
1887                          * to encode the entire ServerECDHParams
1888                          * structure. 
1889                          */
1890                         n = 4 + encodedlen;
1891
1892                         /* We'll generate the serverKeyExchange message
1893                          * explicitly so we can set these to NULLs
1894                          */
1895                         r[0]=NULL;
1896                         r[1]=NULL;
1897                         r[2]=NULL;
1898                         r[3]=NULL;
1899                         }
1900                 else 
1901 #endif /* !OPENSSL_NO_ECDH */
1902 #ifndef OPENSSL_NO_PSK
1903                         if (type & SSL_kPSK)
1904                                 {
1905                                 /* reserve size for record length and PSK identity hint*/
1906                                 n+=2+strlen(s->ctx->psk_identity_hint);
1907                                 }
1908                         else
1909 #endif /* !OPENSSL_NO_PSK */
1910 #ifndef OPENSSL_NO_SRP
1911                 if (type & SSL_kSRP)
1912                         {
1913                         if ((s->srp_ctx.N == NULL) ||
1914                                 (s->srp_ctx.g == NULL) ||
1915                                 (s->srp_ctx.s == NULL) ||
1916                                 (s->srp_ctx.B == NULL))
1917                                 {
1918                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_SRP_PARAM);
1919                                 goto err;
1920                                 }
1921                         r[0]=s->srp_ctx.N;
1922                         r[1]=s->srp_ctx.g;
1923                         r[2]=s->srp_ctx.s;
1924                         r[3]=s->srp_ctx.B;
1925                         }
1926                 else 
1927 #endif
1928                         {
1929                         al=SSL_AD_HANDSHAKE_FAILURE;
1930                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE);
1931                         goto f_err;
1932                         }
1933                 for (i=0; i < 4 && r[i] != NULL; i++)
1934                         {
1935                         nr[i]=BN_num_bytes(r[i]);
1936 #ifndef OPENSSL_NO_SRP
1937                         if ((i == 2) && (type & SSL_kSRP))
1938                                 n+=1+nr[i];
1939                         else
1940 #endif
1941                         n+=2+nr[i];
1942                         }
1943
1944                 if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL)
1945                         && !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
1946                         {
1947                         if ((pkey=ssl_get_sign_pkey(s,s->s3->tmp.new_cipher,&md))
1948                                 == NULL)
1949                                 {
1950                                 al=SSL_AD_DECODE_ERROR;
1951                                 goto f_err;
1952                                 }
1953                         kn=EVP_PKEY_size(pkey);
1954                         }
1955                 else
1956                         {
1957                         pkey=NULL;
1958                         kn=0;
1959                         }
1960
1961                 if (!BUF_MEM_grow_clean(buf,n+SSL_HM_HEADER_LENGTH(s)+kn))
1962                         {
1963                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_BUF);
1964                         goto err;
1965                         }
1966                 d = p = ssl_handshake_start(s);
1967
1968                 for (i=0; i < 4 && r[i] != NULL; i++)
1969                         {
1970 #ifndef OPENSSL_NO_SRP
1971                         if ((i == 2) && (type & SSL_kSRP))
1972                                 {
1973                                 *p = nr[i];
1974                                 p++;
1975                                 }
1976                         else
1977 #endif
1978                         s2n(nr[i],p);
1979                         BN_bn2bin(r[i],p);
1980                         p+=nr[i];
1981                         }
1982
1983 #ifndef OPENSSL_NO_ECDH
1984                 if (type & SSL_kECDHE) 
1985                         {
1986                         /* XXX: For now, we only support named (not generic) curves.
1987                          * In this situation, the serverKeyExchange message has:
1988                          * [1 byte CurveType], [2 byte CurveName]
1989                          * [1 byte length of encoded point], followed by
1990                          * the actual encoded point itself
1991                          */
1992                         *p = NAMED_CURVE_TYPE;
1993                         p += 1;
1994                         *p = 0;
1995                         p += 1;
1996                         *p = curve_id;
1997                         p += 1;
1998                         *p = encodedlen;
1999                         p += 1;
2000                         memcpy((unsigned char*)p, 
2001                             (unsigned char *)encodedPoint, 
2002                             encodedlen);
2003                         OPENSSL_free(encodedPoint);
2004                         encodedPoint = NULL;
2005                         p += encodedlen;
2006                         }
2007 #endif
2008
2009 #ifndef OPENSSL_NO_PSK
2010                 if (type & SSL_kPSK)
2011                         {
2012                         /* copy PSK identity hint */
2013                         s2n(strlen(s->ctx->psk_identity_hint), p); 
2014                         strncpy((char *)p, s->ctx->psk_identity_hint, strlen(s->ctx->psk_identity_hint));
2015                         p+=strlen(s->ctx->psk_identity_hint);
2016                         }
2017 #endif
2018
2019                 /* not anonymous */
2020                 if (pkey != NULL)
2021                         {
2022                         /* n is the length of the params, they start at &(d[4])
2023                          * and p points to the space at the end. */
2024 #ifndef OPENSSL_NO_RSA
2025                         if (pkey->type == EVP_PKEY_RSA && !SSL_USE_SIGALGS(s))
2026                                 {
2027                                 q=md_buf;
2028                                 j=0;
2029                                 for (num=2; num > 0; num--)
2030                                         {
2031                                         EVP_MD_CTX_set_flags(&md_ctx,
2032                                                 EVP_MD_CTX_FLAG_NON_FIPS_ALLOW);
2033                                         EVP_DigestInit_ex(&md_ctx,(num == 2)
2034                                                 ?s->ctx->md5:s->ctx->sha1, NULL);
2035                                         EVP_DigestUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
2036                                         EVP_DigestUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
2037                                         EVP_DigestUpdate(&md_ctx,d,n);
2038                                         EVP_DigestFinal_ex(&md_ctx,q,
2039                                                 (unsigned int *)&i);
2040                                         q+=i;
2041                                         j+=i;
2042                                         }
2043                                 if (RSA_sign(NID_md5_sha1, md_buf, j,
2044                                         &(p[2]), &u, pkey->pkey.rsa) <= 0)
2045                                         {
2046                                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_RSA);
2047                                         goto err;
2048                                         }
2049                                 s2n(u,p);
2050                                 n+=u+2;
2051                                 }
2052                         else
2053 #endif
2054                         if (md)
2055                                 {
2056                                 /* send signature algorithm */
2057                                 if (SSL_USE_SIGALGS(s))
2058                                         {
2059                                         if (!tls12_get_sigandhash(p, pkey, md))
2060                                                 {
2061                                                 /* Should never happen */
2062                                                 al=SSL_AD_INTERNAL_ERROR;
2063                                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_INTERNAL_ERROR);
2064                                                 goto f_err;
2065                                                 }
2066                                         p+=2;
2067                                         }
2068 #ifdef SSL_DEBUG
2069                                 fprintf(stderr, "Using hash %s\n",
2070                                                         EVP_MD_name(md));
2071 #endif
2072                                 EVP_SignInit_ex(&md_ctx, md, NULL);
2073                                 EVP_SignUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
2074                                 EVP_SignUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
2075                                 EVP_SignUpdate(&md_ctx,d,n);
2076                                 if (!EVP_SignFinal(&md_ctx,&(p[2]),
2077                                         (unsigned int *)&i,pkey))
2078                                         {
2079                                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_EVP);
2080                                         goto err;
2081                                         }
2082                                 s2n(i,p);
2083                                 n+=i+2;
2084                                 if (SSL_USE_SIGALGS(s))
2085                                         n+= 2;
2086                                 }
2087                         else
2088                                 {
2089                                 /* Is this error check actually needed? */
2090                                 al=SSL_AD_HANDSHAKE_FAILURE;
2091                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_PKEY_TYPE);
2092                                 goto f_err;
2093                                 }
2094                         }
2095
2096                 ssl_set_handshake_header(s, SSL3_MT_SERVER_KEY_EXCHANGE, n);
2097                 }
2098
2099         s->state = SSL3_ST_SW_KEY_EXCH_B;
2100         EVP_MD_CTX_cleanup(&md_ctx);
2101         return ssl_do_write(s);
2102 f_err:
2103         ssl3_send_alert(s,SSL3_AL_FATAL,al);
2104 err:
2105 #ifndef OPENSSL_NO_ECDH
2106         if (encodedPoint != NULL) OPENSSL_free(encodedPoint);
2107         BN_CTX_free(bn_ctx);
2108 #endif
2109         EVP_MD_CTX_cleanup(&md_ctx);
2110         return(-1);
2111         }
2112
2113 int ssl3_send_certificate_request(SSL *s)
2114         {
2115         unsigned char *p,*d;
2116         int i,j,nl,off,n;
2117         STACK_OF(X509_NAME) *sk=NULL;
2118         X509_NAME *name;
2119         BUF_MEM *buf;
2120
2121         if (s->state == SSL3_ST_SW_CERT_REQ_A)
2122                 {
2123                 buf=s->init_buf;
2124
2125                 d=p=ssl_handshake_start(s);
2126
2127                 /* get the list of acceptable cert types */
2128                 p++;
2129                 n=ssl3_get_req_cert_type(s,p);
2130                 d[0]=n;
2131                 p+=n;
2132                 n++;
2133
2134                 if (SSL_USE_SIGALGS(s))
2135                         {
2136                         const unsigned char *psigs;
2137                         unsigned char *etmp = p;
2138                         nl = tls12_get_psigalgs(s, &psigs);
2139                         /* Skip over length for now */
2140                         p += 2;
2141                         nl = tls12_copy_sigalgs(s, p, psigs, nl);
2142                         /* Now fill in length */
2143                         s2n(nl, etmp);
2144                         p += nl;
2145                         n += nl + 2;
2146                         }
2147
2148                 off=n;
2149                 p+=2;
2150                 n+=2;
2151
2152                 sk=SSL_get_client_CA_list(s);
2153                 nl=0;
2154                 if (sk != NULL)
2155                         {
2156                         for (i=0; i<sk_X509_NAME_num(sk); i++)
2157                                 {
2158                                 name=sk_X509_NAME_value(sk,i);
2159                                 j=i2d_X509_NAME(name,NULL);
2160                                 if (!BUF_MEM_grow_clean(buf,SSL_HM_HEADER_LENGTH(s)+n+j+2))
2161                                         {
2162                                         SSLerr(SSL_F_SSL3_SEND_CERTIFICATE_REQUEST,ERR_R_BUF_LIB);
2163                                         goto err;
2164                                         }
2165                                 p = ssl_handshake_start(s) + n;
2166                                 if (!(s->options & SSL_OP_NETSCAPE_CA_DN_BUG))
2167                                         {
2168                                         s2n(j,p);
2169                                         i2d_X509_NAME(name,&p);
2170                                         n+=2+j;
2171                                         nl+=2+j;
2172                                         }
2173                                 else
2174                                         {
2175                                         d=p;
2176                                         i2d_X509_NAME(name,&p);
2177                                         j-=2; s2n(j,d); j+=2;
2178                                         n+=j;
2179                                         nl+=j;
2180                                         }
2181                                 }
2182                         }
2183                 /* else no CA names */
2184                 p = ssl_handshake_start(s) + off;
2185                 s2n(nl,p);
2186
2187                 ssl_set_handshake_header(s, SSL3_MT_CERTIFICATE_REQUEST, n);
2188
2189 #ifdef NETSCAPE_HANG_BUG
2190                 if (!SSL_IS_DTLS(s))
2191                         {
2192                         if (!BUF_MEM_grow_clean(buf, s->init_num + 4))
2193                                 {
2194                                 SSLerr(SSL_F_SSL3_SEND_CERTIFICATE_REQUEST,ERR_R_BUF_LIB);
2195                                 goto err;
2196                                 }
2197                         p=(unsigned char *)s->init_buf->data + s->init_num;
2198                         /* do the header */
2199                         *(p++)=SSL3_MT_SERVER_DONE;
2200                         *(p++)=0;
2201                         *(p++)=0;
2202                         *(p++)=0;
2203                         s->init_num += 4;
2204                         }
2205 #endif
2206
2207                 s->state = SSL3_ST_SW_CERT_REQ_B;
2208                 }
2209
2210         /* SSL3_ST_SW_CERT_REQ_B */
2211         return ssl_do_write(s);
2212 err:
2213         return(-1);
2214         }
2215
2216 int ssl3_get_client_key_exchange(SSL *s)
2217         {
2218         int i,al,ok;
2219         long n;
2220         unsigned long alg_k;
2221         unsigned char *p;
2222 #ifndef OPENSSL_NO_RSA
2223         RSA *rsa=NULL;
2224         EVP_PKEY *pkey=NULL;
2225 #endif
2226 #ifndef OPENSSL_NO_DH
2227         BIGNUM *pub=NULL;
2228         DH *dh_srvr, *dh_clnt = NULL;
2229 #endif
2230 #ifndef OPENSSL_NO_KRB5
2231         KSSL_ERR kssl_err;
2232 #endif /* OPENSSL_NO_KRB5 */
2233
2234 #ifndef OPENSSL_NO_ECDH
2235         EC_KEY *srvr_ecdh = NULL;
2236         EVP_PKEY *clnt_pub_pkey = NULL;
2237         EC_POINT *clnt_ecpoint = NULL;
2238         BN_CTX *bn_ctx = NULL; 
2239 #endif
2240
2241         n=s->method->ssl_get_message(s,
2242                 SSL3_ST_SR_KEY_EXCH_A,
2243                 SSL3_ST_SR_KEY_EXCH_B,
2244                 SSL3_MT_CLIENT_KEY_EXCHANGE,
2245                 2048, /* ??? */
2246                 &ok);
2247
2248         if (!ok) return((int)n);
2249         p=(unsigned char *)s->init_msg;
2250
2251         alg_k=s->s3->tmp.new_cipher->algorithm_mkey;
2252
2253 #ifndef OPENSSL_NO_RSA
2254         if (alg_k & SSL_kRSA)
2255                 {
2256                 unsigned char rand_premaster_secret[SSL_MAX_MASTER_KEY_LENGTH];
2257                 int decrypt_len, decrypt_good_mask;
2258                 unsigned char version_good;
2259
2260                 /* FIX THIS UP EAY EAY EAY EAY */
2261                 if (s->s3->tmp.use_rsa_tmp)
2262                         {
2263                         if ((s->cert != NULL) && (s->cert->rsa_tmp != NULL))
2264                                 rsa=s->cert->rsa_tmp;
2265                         /* Don't do a callback because rsa_tmp should
2266                          * be sent already */
2267                         if (rsa == NULL)
2268                                 {
2269                                 al=SSL_AD_HANDSHAKE_FAILURE;
2270                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_TMP_RSA_PKEY);
2271                                 goto f_err;
2272
2273                                 }
2274                         }
2275                 else
2276                         {
2277                         pkey=s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey;
2278                         if (    (pkey == NULL) ||
2279                                 (pkey->type != EVP_PKEY_RSA) ||
2280                                 (pkey->pkey.rsa == NULL))
2281                                 {
2282                                 al=SSL_AD_HANDSHAKE_FAILURE;
2283                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_RSA_CERTIFICATE);
2284                                 goto f_err;
2285                                 }
2286                         rsa=pkey->pkey.rsa;
2287                         }
2288
2289                 /* TLS and [incidentally] DTLS{0xFEFF} */
2290                 if (s->version > SSL3_VERSION && s->version != DTLS1_BAD_VER)
2291                         {
2292                         n2s(p,i);
2293                         if (n != i+2)
2294                                 {
2295                                 if (!(s->options & SSL_OP_TLS_D5_BUG))
2296                                         {
2297                                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_TLS_RSA_ENCRYPTED_VALUE_LENGTH_IS_WRONG);
2298                                         goto err;
2299                                         }
2300                                 else
2301                                         p-=2;
2302                                 }
2303                         else
2304                                 n=i;
2305                         }
2306
2307                 /* We must not leak whether a decryption failure occurs because
2308                  * of Bleichenbacher's attack on PKCS #1 v1.5 RSA padding (see
2309                  * RFC 2246, section 7.4.7.1). The code follows that advice of
2310                  * the TLS RFC and generates a random premaster secret for the
2311                  * case that the decrypt fails. See
2312                  * https://tools.ietf.org/html/rfc5246#section-7.4.7.1 */
2313
2314                 /* should be RAND_bytes, but we cannot work around a failure. */
2315                 if (RAND_pseudo_bytes(rand_premaster_secret,
2316                                       sizeof(rand_premaster_secret)) <= 0)
2317                         goto err;
2318                 decrypt_len = RSA_private_decrypt((int)n,p,p,rsa,RSA_PKCS1_PADDING);
2319                 ERR_clear_error();
2320
2321                 /* decrypt_len should be SSL_MAX_MASTER_KEY_LENGTH.
2322                  * decrypt_good_mask will be zero if so and non-zero otherwise. */
2323                 decrypt_good_mask = decrypt_len ^ SSL_MAX_MASTER_KEY_LENGTH;
2324
2325                 /* If the version in the decrypted pre-master secret is correct
2326                  * then version_good will be zero. The Klima-Pokorny-Rosa
2327                  * extension of Bleichenbacher's attack
2328                  * (http://eprint.iacr.org/2003/052/) exploits the version
2329                  * number check as a "bad version oracle". Thus version checks
2330                  * are done in constant time and are treated like any other
2331                  * decryption error. */
2332                 version_good = p[0] ^ (s->client_version>>8);
2333                 version_good |= p[1] ^ (s->client_version&0xff);
2334
2335                 /* The premaster secret must contain the same version number as
2336                  * the ClientHello to detect version rollback attacks
2337                  * (strangely, the protocol does not offer such protection for
2338                  * DH ciphersuites). However, buggy clients exist that send the
2339                  * negotiated protocol version instead if the server does not
2340                  * support the requested protocol version. If
2341                  * SSL_OP_TLS_ROLLBACK_BUG is set, tolerate such clients. */
2342                 if (s->options & SSL_OP_TLS_ROLLBACK_BUG)
2343                         {
2344                         unsigned char workaround_mask = version_good;
2345                         unsigned char workaround;
2346
2347                         /* workaround_mask will be 0xff if version_good is
2348                          * non-zero (i.e. the version match failed). Otherwise
2349                          * it'll be 0x00. */
2350                         workaround_mask |= workaround_mask >> 4;
2351                         workaround_mask |= workaround_mask >> 2;
2352                         workaround_mask |= workaround_mask >> 1;
2353                         workaround_mask = ~((workaround_mask & 1) - 1);
2354
2355                         workaround = p[0] ^ (s->version>>8);
2356                         workaround |= p[1] ^ (s->version&0xff);
2357
2358                         /* If workaround_mask is 0xff (i.e. there was a version
2359                          * mismatch) then we copy the value of workaround over
2360                          * version_good. */
2361                         version_good = (workaround & workaround_mask) |
2362                                        (version_good & ~workaround_mask);
2363                         }
2364
2365                 /* If any bits in version_good are set then they'll poision
2366                  * decrypt_good_mask and cause rand_premaster_secret to be
2367                  * used. */
2368                 decrypt_good_mask |= version_good;
2369
2370                 /* decrypt_good_mask will be zero iff decrypt_len ==
2371                  * SSL_MAX_MASTER_KEY_LENGTH and the version check passed. We
2372                  * fold the bottom 32 bits of it with an OR so that the LSB
2373                  * will be zero iff everything is good. This assumes that we'll
2374                  * never decrypt a value > 2**31 bytes, which seems safe. */
2375                 decrypt_good_mask |= decrypt_good_mask >> 16;
2376                 decrypt_good_mask |= decrypt_good_mask >> 8;
2377                 decrypt_good_mask |= decrypt_good_mask >> 4;
2378                 decrypt_good_mask |= decrypt_good_mask >> 2;
2379                 decrypt_good_mask |= decrypt_good_mask >> 1;
2380                 /* Now select only the LSB and subtract one. If decrypt_len ==
2381                  * SSL_MAX_MASTER_KEY_LENGTH and the version check passed then
2382                  * decrypt_good_mask will be all ones. Otherwise it'll be all
2383                  * zeros. */
2384                 decrypt_good_mask &= 1;
2385                 decrypt_good_mask--;
2386
2387                 /* Now copy rand_premaster_secret over p using
2388                  * decrypt_good_mask. */
2389                 for (i = 0; i < (int) sizeof(rand_premaster_secret); i++)
2390                         {
2391                         p[i] = (p[i] & decrypt_good_mask) |
2392                                (rand_premaster_secret[i] & ~decrypt_good_mask);
2393                         }
2394
2395                 s->session->master_key_length=
2396                         s->method->ssl3_enc->generate_master_secret(s,
2397                                 s->session->master_key,
2398                                 p,i);
2399                 OPENSSL_cleanse(p,i);
2400                 }
2401         else
2402 #endif
2403 #ifndef OPENSSL_NO_DH
2404                 if (alg_k & (SSL_kDHE|SSL_kDHr|SSL_kDHd))
2405                 {
2406                 int idx = -1;
2407                 EVP_PKEY *skey = NULL;
2408                 if (n)
2409                         n2s(p,i);
2410                 else
2411                         i = 0;
2412                 if (n && n != i+2)
2413                         {
2414                         if (!(s->options & SSL_OP_SSLEAY_080_CLIENT_DH_BUG))
2415                                 {
2416                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_DH_PUBLIC_VALUE_LENGTH_IS_WRONG);
2417                                 goto err;
2418                                 }
2419                         else
2420                                 {
2421                                 p-=2;
2422                                 i=(int)n;
2423                                 }
2424                         }
2425                 if (alg_k & SSL_kDHr)
2426                         idx = SSL_PKEY_DH_RSA;
2427                 else if (alg_k & SSL_kDHd)
2428                         idx = SSL_PKEY_DH_DSA;
2429                 if (idx >= 0)
2430                         {
2431                         skey = s->cert->pkeys[idx].privatekey;
2432                         if ((skey == NULL) ||
2433                                 (skey->type != EVP_PKEY_DH) ||
2434                                 (skey->pkey.dh == NULL))
2435                                 {
2436                                 al=SSL_AD_HANDSHAKE_FAILURE;
2437                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_RSA_CERTIFICATE);
2438                                 goto f_err;
2439                                 }
2440                         dh_srvr = skey->pkey.dh;
2441                         }
2442                 else if (s->s3->tmp.dh == NULL)
2443                         {
2444                         al=SSL_AD_HANDSHAKE_FAILURE;
2445                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
2446                         goto f_err;
2447                         }
2448                 else
2449                         dh_srvr=s->s3->tmp.dh;
2450
2451                 if (n == 0L)
2452                         {
2453                         /* Get pubkey from cert */
2454                         EVP_PKEY *clkey=X509_get_pubkey(s->session->peer);
2455                         if (clkey)
2456                                 {
2457                                 if (EVP_PKEY_cmp_parameters(clkey, skey) == 1)
2458                                         dh_clnt = EVP_PKEY_get1_DH(clkey);
2459                                 }
2460                         if (dh_clnt == NULL)
2461                                 {
2462                                 al=SSL_AD_HANDSHAKE_FAILURE;
2463                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
2464                                 goto f_err;
2465                                 }
2466                         EVP_PKEY_free(clkey);
2467                         pub = dh_clnt->pub_key;
2468                         }
2469                 else
2470                         pub=BN_bin2bn(p,i,NULL);
2471                 if (pub == NULL)
2472                         {
2473                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_BN_LIB);
2474                         goto err;
2475                         }
2476
2477                 i=DH_compute_key(p,pub,dh_srvr);
2478
2479                 if (i <= 0)
2480                         {
2481                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,ERR_R_DH_LIB);
2482                         BN_clear_free(pub);
2483                         goto err;
2484                         }
2485
2486                 DH_free(s->s3->tmp.dh);
2487                 s->s3->tmp.dh=NULL;
2488                 if (dh_clnt)
2489                         DH_free(dh_clnt);
2490                 else
2491                         BN_clear_free(pub);
2492                 pub=NULL;
2493                 s->session->master_key_length=
2494                         s->method->ssl3_enc->generate_master_secret(s,
2495                                 s->session->master_key,p,i);
2496                 OPENSSL_cleanse(p,i);
2497                 if (dh_clnt)
2498                         return 2;
2499                 }
2500         else
2501 #endif
2502 #ifndef OPENSSL_NO_KRB5
2503         if (alg_k & SSL_kKRB5)
2504                 {
2505                 krb5_error_code         krb5rc;
2506                 krb5_data               enc_ticket;
2507                 krb5_data               authenticator;
2508                 krb5_data               enc_pms;
2509                 KSSL_CTX                *kssl_ctx = s->kssl_ctx;
2510                 EVP_CIPHER_CTX          ciph_ctx;
2511                 const EVP_CIPHER        *enc = NULL;
2512                 unsigned char           iv[EVP_MAX_IV_LENGTH];
2513                 unsigned char           pms[SSL_MAX_MASTER_KEY_LENGTH
2514                                                + EVP_MAX_BLOCK_LENGTH];
2515                 int                  padl, outl;
2516                 krb5_timestamp          authtime = 0;
2517                 krb5_ticket_times       ttimes;
2518
2519                 EVP_CIPHER_CTX_init(&ciph_ctx);
2520
2521                 if (!kssl_ctx)  kssl_ctx = kssl_ctx_new();
2522
2523                 n2s(p,i);
2524                 enc_ticket.length = i;
2525
2526                 if (n < (long)(enc_ticket.length + 6))
2527                         {
2528                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2529                                 SSL_R_DATA_LENGTH_TOO_LONG);
2530                         goto err;
2531                         }
2532
2533                 enc_ticket.data = (char *)p;
2534                 p+=enc_ticket.length;
2535
2536                 n2s(p,i);
2537                 authenticator.length = i;
2538
2539                 if (n < (long)(enc_ticket.length + authenticator.length + 6))
2540                         {
2541                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2542                                 SSL_R_DATA_LENGTH_TOO_LONG);
2543                         goto err;
2544                         }
2545
2546                 authenticator.data = (char *)p;
2547                 p+=authenticator.length;
2548
2549                 n2s(p,i);
2550                 enc_pms.length = i;
2551                 enc_pms.data = (char *)p;
2552                 p+=enc_pms.length;
2553
2554                 /* Note that the length is checked again below,
2555                 ** after decryption
2556                 */
2557                 if(enc_pms.length > sizeof pms)
2558                         {
2559                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2560                                SSL_R_DATA_LENGTH_TOO_LONG);
2561                         goto err;
2562                         }
2563
2564                 if (n != (long)(enc_ticket.length + authenticator.length +
2565                                                 enc_pms.length + 6))
2566                         {
2567                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2568                                 SSL_R_DATA_LENGTH_TOO_LONG);
2569                         goto err;
2570                         }
2571
2572                 if ((krb5rc = kssl_sget_tkt(kssl_ctx, &enc_ticket, &ttimes,
2573                                         &kssl_err)) != 0)
2574                         {
2575 #ifdef KSSL_DEBUG
2576                         printf("kssl_sget_tkt rtn %d [%d]\n",
2577                                 krb5rc, kssl_err.reason);
2578                         if (kssl_err.text)
2579                                 printf("kssl_err text= %s\n", kssl_err.text);
2580 #endif  /* KSSL_DEBUG */
2581                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2582                                 kssl_err.reason);
2583                         goto err;
2584                         }
2585
2586                 /*  Note: no authenticator is not considered an error,
2587                 **  but will return authtime == 0.
2588                 */
2589                 if ((krb5rc = kssl_check_authent(kssl_ctx, &authenticator,
2590                                         &authtime, &kssl_err)) != 0)
2591                         {
2592 #ifdef KSSL_DEBUG
2593                         printf("kssl_check_authent rtn %d [%d]\n",
2594                                 krb5rc, kssl_err.reason);
2595                         if (kssl_err.text)
2596                                 printf("kssl_err text= %s\n", kssl_err.text);
2597 #endif  /* KSSL_DEBUG */
2598                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2599                                 kssl_err.reason);
2600                         goto err;
2601                         }
2602
2603                 if ((krb5rc = kssl_validate_times(authtime, &ttimes)) != 0)
2604                         {
2605                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE, krb5rc);
2606                         goto err;
2607                         }
2608
2609 #ifdef KSSL_DEBUG
2610                 kssl_ctx_show(kssl_ctx);
2611 #endif  /* KSSL_DEBUG */
2612
2613                 enc = kssl_map_enc(kssl_ctx->enctype);
2614                 if (enc == NULL)
2615                     goto err;
2616
2617                 memset(iv, 0, sizeof iv);       /* per RFC 1510 */
2618
2619                 if (!EVP_DecryptInit_ex(&ciph_ctx,enc,NULL,kssl_ctx->key,iv))
2620                         {
2621                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2622                                 SSL_R_DECRYPTION_FAILED);
2623                         goto err;
2624                         }
2625                 if (!EVP_DecryptUpdate(&ciph_ctx, pms,&outl,
2626                                         (unsigned char *)enc_pms.data, enc_pms.length))
2627                         {
2628                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2629                                 SSL_R_DECRYPTION_FAILED);
2630                         goto err;
2631                         }
2632                 if (outl > SSL_MAX_MASTER_KEY_LENGTH)
2633                         {
2634                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2635                                 SSL_R_DATA_LENGTH_TOO_LONG);
2636                         goto err;
2637                         }
2638                 if (!EVP_DecryptFinal_ex(&ciph_ctx,&(pms[outl]),&padl))
2639                         {
2640                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2641                                 SSL_R_DECRYPTION_FAILED);
2642                         goto err;
2643                         }
2644                 outl += padl;
2645                 if (outl > SSL_MAX_MASTER_KEY_LENGTH)
2646                         {
2647                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2648                                 SSL_R_DATA_LENGTH_TOO_LONG);
2649                         goto err;
2650                         }
2651                 if (!((pms[0] == (s->client_version>>8)) && (pms[1] == (s->client_version & 0xff))))
2652                     {
2653                     /* The premaster secret must contain the same version number as the
2654                      * ClientHello to detect version rollback attacks (strangely, the
2655                      * protocol does not offer such protection for DH ciphersuites).
2656                      * However, buggy clients exist that send random bytes instead of
2657                      * the protocol version.
2658                      * If SSL_OP_TLS_ROLLBACK_BUG is set, tolerate such clients. 
2659                      * (Perhaps we should have a separate BUG value for the Kerberos cipher)
2660                      */
2661                     if (!(s->options & SSL_OP_TLS_ROLLBACK_BUG))
2662                         {
2663                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2664                                SSL_AD_DECODE_ERROR);
2665                         goto err;
2666                         }
2667                     }
2668
2669                 EVP_CIPHER_CTX_cleanup(&ciph_ctx);
2670
2671                 s->session->master_key_length=
2672                         s->method->ssl3_enc->generate_master_secret(s,
2673                                 s->session->master_key, pms, outl);
2674
2675                 if (kssl_ctx->client_princ)
2676                         {
2677                         size_t len = strlen(kssl_ctx->client_princ);
2678                         if ( len < SSL_MAX_KRB5_PRINCIPAL_LENGTH ) 
2679                                 {
2680                                 s->session->krb5_client_princ_len = len;
2681                                 memcpy(s->session->krb5_client_princ,kssl_ctx->client_princ,len);
2682                                 }
2683                         }
2684
2685
2686                 /*  Was doing kssl_ctx_free() here,
2687                 **  but it caused problems for apache.
2688                 **  kssl_ctx = kssl_ctx_free(kssl_ctx);
2689                 **  if (s->kssl_ctx)  s->kssl_ctx = NULL;
2690                 */
2691                 }
2692         else
2693 #endif  /* OPENSSL_NO_KRB5 */
2694
2695 #ifndef OPENSSL_NO_ECDH
2696                 if (alg_k & (SSL_kECDHE|SSL_kECDHr|SSL_kECDHe))
2697                 {
2698                 int ret = 1;
2699                 int field_size = 0;
2700                 const EC_KEY   *tkey;
2701                 const EC_GROUP *group;
2702                 const BIGNUM *priv_key;
2703
2704                 /* initialize structures for server's ECDH key pair */
2705                 if ((srvr_ecdh = EC_KEY_new()) == NULL) 
2706                         {
2707                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2708                             ERR_R_MALLOC_FAILURE);
2709                         goto err;
2710                         }
2711
2712                 /* Let's get server private key and group information */
2713                 if (alg_k & (SSL_kECDHr|SSL_kECDHe))
2714                         { 
2715                         /* use the certificate */
2716                         tkey = s->cert->pkeys[SSL_PKEY_ECC].privatekey->pkey.ec;
2717                         }
2718                 else
2719                         {
2720                         /* use the ephermeral values we saved when
2721                          * generating the ServerKeyExchange msg.
2722                          */
2723                         tkey = s->s3->tmp.ecdh;
2724                         }
2725
2726                 group    = EC_KEY_get0_group(tkey);
2727                 priv_key = EC_KEY_get0_private_key(tkey);
2728
2729                 if (!EC_KEY_set_group(srvr_ecdh, group) ||
2730                     !EC_KEY_set_private_key(srvr_ecdh, priv_key))
2731                         {
2732                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2733                                ERR_R_EC_LIB);
2734                         goto err;
2735                         }
2736
2737                 /* Let's get client's public key */
2738                 if ((clnt_ecpoint = EC_POINT_new(group)) == NULL)
2739                         {
2740                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2741                             ERR_R_MALLOC_FAILURE);
2742                         goto err;
2743                         }
2744
2745                 if (n == 0L) 
2746                         {
2747                         /* Client Publickey was in Client Certificate */
2748
2749                          if (alg_k & SSL_kECDHE)
2750                                  {
2751                                  al=SSL_AD_HANDSHAKE_FAILURE;
2752                                  SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_TMP_ECDH_KEY);
2753                                  goto f_err;
2754                                  }
2755                         if (((clnt_pub_pkey=X509_get_pubkey(s->session->peer))
2756                             == NULL) || 
2757                             (clnt_pub_pkey->type != EVP_PKEY_EC))
2758                                 {
2759                                 /* XXX: For now, we do not support client
2760                                  * authentication using ECDH certificates
2761                                  * so this branch (n == 0L) of the code is
2762                                  * never executed. When that support is
2763                                  * added, we ought to ensure the key 
2764                                  * received in the certificate is 
2765                                  * authorized for key agreement.
2766                                  * ECDH_compute_key implicitly checks that
2767                                  * the two ECDH shares are for the same
2768                                  * group.
2769                                  */
2770                                 al=SSL_AD_HANDSHAKE_FAILURE;
2771                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2772                                     SSL_R_UNABLE_TO_DECODE_ECDH_CERTS);
2773                                 goto f_err;
2774                                 }
2775
2776                         if (EC_POINT_copy(clnt_ecpoint,
2777                             EC_KEY_get0_public_key(clnt_pub_pkey->pkey.ec)) == 0)
2778                                 {
2779                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2780                                         ERR_R_EC_LIB);
2781                                 goto err;
2782                                 }
2783                         ret = 2; /* Skip certificate verify processing */
2784                         }
2785                 else
2786                         {
2787                         /* Get client's public key from encoded point
2788                          * in the ClientKeyExchange message.
2789                          */
2790                         if ((bn_ctx = BN_CTX_new()) == NULL)
2791                                 {
2792                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2793                                     ERR_R_MALLOC_FAILURE);
2794                                 goto err;
2795                                 }
2796
2797                         /* Get encoded point length */
2798                         i = *p; 
2799                         p += 1;
2800                         if (n != 1 + i)
2801                                 {
2802                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2803                                     ERR_R_EC_LIB);
2804                                 goto err;
2805                                 }
2806                         if (EC_POINT_oct2point(group, 
2807                             clnt_ecpoint, p, i, bn_ctx) == 0)
2808                                 {
2809                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2810                                     ERR_R_EC_LIB);
2811                                 goto err;
2812                                 }
2813                         /* p is pointing to somewhere in the buffer
2814                          * currently, so set it to the start 
2815                          */ 
2816                         p=(unsigned char *)s->init_buf->data;
2817                         }
2818
2819                 /* Compute the shared pre-master secret */
2820                 field_size = EC_GROUP_get_degree(group);
2821                 if (field_size <= 0)
2822                         {
2823                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE, 
2824                                ERR_R_ECDH_LIB);
2825                         goto err;
2826                         }
2827                 i = ECDH_compute_key(p, (field_size+7)/8, clnt_ecpoint, srvr_ecdh, NULL);
2828                 if (i <= 0)
2829                         {
2830                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2831                             ERR_R_ECDH_LIB);
2832                         goto err;
2833                         }
2834
2835                 EVP_PKEY_free(clnt_pub_pkey);
2836                 EC_POINT_free(clnt_ecpoint);
2837                 EC_KEY_free(srvr_ecdh);
2838                 BN_CTX_free(bn_ctx);
2839                 EC_KEY_free(s->s3->tmp.ecdh);
2840                 s->s3->tmp.ecdh = NULL; 
2841
2842                 /* Compute the master secret */
2843                 s->session->master_key_length = s->method->ssl3_enc-> \
2844                     generate_master_secret(s, s->session->master_key, p, i);
2845                 
2846                 OPENSSL_cleanse(p, i);
2847                 return (ret);
2848                 }
2849         else
2850 #endif
2851 #ifndef OPENSSL_NO_PSK
2852                 if (alg_k & SSL_kPSK)
2853                         {
2854                         unsigned char *t = NULL;
2855                         unsigned char psk_or_pre_ms[PSK_MAX_PSK_LEN*2+4];
2856                         unsigned int pre_ms_len = 0, psk_len = 0;
2857                         int psk_err = 1;
2858                         char tmp_id[PSK_MAX_IDENTITY_LEN+1];
2859
2860                         al=SSL_AD_HANDSHAKE_FAILURE;
2861
2862                         n2s(p,i);
2863                         if (n != i+2)
2864                                 {
2865                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2866                                         SSL_R_LENGTH_MISMATCH);
2867                                 goto psk_err;
2868                                 }
2869                         if (i > PSK_MAX_IDENTITY_LEN)
2870                                 {
2871                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2872                                         SSL_R_DATA_LENGTH_TOO_LONG);
2873                                 goto psk_err;
2874                                 }
2875                         if (s->psk_server_callback == NULL)
2876                                 {
2877                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2878                                        SSL_R_PSK_NO_SERVER_CB);
2879                                 goto psk_err;
2880                                 }
2881
2882                         /* Create guaranteed NULL-terminated identity
2883                          * string for the callback */
2884                         memcpy(tmp_id, p, i);
2885                         memset(tmp_id+i, 0, PSK_MAX_IDENTITY_LEN+1-i);
2886                         psk_len = s->psk_server_callback(s, tmp_id,
2887                                 psk_or_pre_ms, sizeof(psk_or_pre_ms));
2888                         OPENSSL_cleanse(tmp_id, PSK_MAX_IDENTITY_LEN+1);
2889
2890                         if (psk_len > PSK_MAX_PSK_LEN)
2891                                 {
2892                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2893                                         ERR_R_INTERNAL_ERROR);
2894                                 goto psk_err;
2895                                 }
2896                         else if (psk_len == 0)
2897                                 {
2898                                 /* PSK related to the given identity not found */
2899                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2900                                        SSL_R_PSK_IDENTITY_NOT_FOUND);
2901                                 al=SSL_AD_UNKNOWN_PSK_IDENTITY;
2902                                 goto psk_err;
2903                                 }
2904
2905                         /* create PSK pre_master_secret */
2906                         pre_ms_len=2+psk_len+2+psk_len;
2907                         t = psk_or_pre_ms;
2908                         memmove(psk_or_pre_ms+psk_len+4, psk_or_pre_ms, psk_len);
2909                         s2n(psk_len, t);
2910                         memset(t, 0, psk_len);
2911                         t+=psk_len;
2912                         s2n(psk_len, t);
2913
2914                         if (s->session->psk_identity != NULL)
2915                                 OPENSSL_free(s->session->psk_identity);
2916                         s->session->psk_identity = BUF_strdup((char *)p);
2917                         if (s->session->psk_identity == NULL)
2918                                 {
2919                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2920                                         ERR_R_MALLOC_FAILURE);
2921                                 goto psk_err;
2922                                 }
2923
2924                         if (s->session->psk_identity_hint != NULL)
2925                                 OPENSSL_free(s->session->psk_identity_hint);
2926                         s->session->psk_identity_hint = BUF_strdup(s->ctx->psk_identity_hint);
2927                         if (s->ctx->psk_identity_hint != NULL &&
2928                                 s->session->psk_identity_hint == NULL)
2929                                 {
2930                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2931                                         ERR_R_MALLOC_FAILURE);
2932                                 goto psk_err;
2933                                 }
2934
2935                         s->session->master_key_length=
2936                                 s->method->ssl3_enc->generate_master_secret(s,
2937                                         s->session->master_key, psk_or_pre_ms, pre_ms_len);
2938                         psk_err = 0;
2939                 psk_err:
2940                         OPENSSL_cleanse(psk_or_pre_ms, sizeof(psk_or_pre_ms));
2941                         if (psk_err != 0)
2942                                 goto f_err;
2943                         }
2944                 else
2945 #endif
2946 #ifndef OPENSSL_NO_SRP
2947                 if (alg_k & SSL_kSRP)
2948                         {
2949                         int param_len;
2950
2951                         n2s(p,i);
2952                         param_len=i+2;
2953                         if (param_len > n)
2954                                 {
2955                                 al=SSL_AD_DECODE_ERROR;
2956                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_BAD_SRP_A_LENGTH);
2957                                 goto f_err;
2958                                 }
2959                         if (!(s->srp_ctx.A=BN_bin2bn(p,i,NULL)))
2960                                 {
2961                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,ERR_R_BN_LIB);
2962                                 goto err;
2963                                 }
2964                         if (s->session->srp_username != NULL)
2965                                 OPENSSL_free(s->session->srp_username);
2966                         s->session->srp_username = BUF_strdup(s->srp_ctx.login);
2967                         if (s->session->srp_username == NULL)
2968                                 {
2969                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2970                                         ERR_R_MALLOC_FAILURE);
2971                                 goto err;
2972                                 }
2973
2974                         if ((s->session->master_key_length = SRP_generate_server_master_secret(s,s->session->master_key))<0)
2975                                 {
2976                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,ERR_R_INTERNAL_ERROR);
2977                                 goto err;
2978                                 }
2979
2980                         p+=i;
2981                         }
2982                 else
2983 #endif  /* OPENSSL_NO_SRP */
2984                 if (alg_k & SSL_kGOST) 
2985                         {
2986                         int ret = 0;
2987                         EVP_PKEY_CTX *pkey_ctx;
2988                         EVP_PKEY *client_pub_pkey = NULL, *pk = NULL;
2989                         unsigned char premaster_secret[32], *start;
2990                         size_t outlen=32, inlen;
2991                         unsigned long alg_a;
2992                         int Ttag, Tclass;
2993                         long Tlen;
2994
2995                         /* Get our certificate private key*/
2996                         alg_a = s->s3->tmp.new_cipher->algorithm_auth;
2997                         if (alg_a & SSL_aGOST94)
2998                                 pk = s->cert->pkeys[SSL_PKEY_GOST94].privatekey;
2999                         else if (alg_a & SSL_aGOST01)
3000                                 pk = s->cert->pkeys[SSL_PKEY_GOST01].privatekey;
3001
3002                         pkey_ctx = EVP_PKEY_CTX_new(pk,NULL);
3003                         EVP_PKEY_decrypt_init(pkey_ctx);
3004                         /* If client certificate is present and is of the same type, maybe
3005                          * use it for key exchange.  Don't mind errors from
3006                          * EVP_PKEY_derive_set_peer, because it is completely valid to use
3007                          * a client certificate for authorization only. */
3008                         client_pub_pkey = X509_get_pubkey(s->session->peer);
3009                         if (client_pub_pkey)
3010                                 {
3011                                 if (EVP_PKEY_derive_set_peer(pkey_ctx, client_pub_pkey) <= 0)
3012                                         ERR_clear_error();
3013                                 }
3014                         /* Decrypt session key */
3015                         if (ASN1_get_object((const unsigned char **)&p, &Tlen, &Ttag, &Tclass, n) != V_ASN1_CONSTRUCTED || 
3016                                 Ttag != V_ASN1_SEQUENCE ||
3017                                 Tclass != V_ASN1_UNIVERSAL) 
3018                                 {
3019                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_DECRYPTION_FAILED);
3020                                 goto gerr;
3021                                 }
3022                         start = p;
3023                         inlen = Tlen;
3024                         if (EVP_PKEY_decrypt(pkey_ctx,premaster_secret,&outlen,start,inlen) <=0) 
3025
3026                                 {
3027                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_DECRYPTION_FAILED);
3028                                 goto gerr;
3029                                 }
3030                         /* Generate master secret */
3031                         s->session->master_key_length=
3032                                 s->method->ssl3_enc->generate_master_secret(s,
3033                                         s->session->master_key,premaster_secret,32);
3034                         /* Check if pubkey from client certificate was used */
3035                         if (EVP_PKEY_CTX_ctrl(pkey_ctx, -1, -1, EVP_PKEY_CTRL_PEER_KEY, 2, NULL) > 0)
3036                                 ret = 2;
3037                         else
3038                                 ret = 1;
3039                 gerr:
3040                         EVP_PKEY_free(client_pub_pkey);
3041                         EVP_PKEY_CTX_free(pkey_ctx);
3042                         if (ret)
3043                                 return ret;
3044                         else
3045                                 goto err;
3046                         }
3047                 else
3048                 {
3049                 al=SSL_AD_HANDSHAKE_FAILURE;
3050                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
3051                                 SSL_R_UNKNOWN_CIPHER_TYPE);
3052                 goto f_err;
3053                 }
3054
3055         return(1);
3056 f_err:
3057         ssl3_send_alert(s,SSL3_AL_FATAL,al);
3058 #if !defined(OPENSSL_NO_DH) || !defined(OPENSSL_NO_RSA) || !defined(OPENSSL_NO_ECDH) || defined(OPENSSL_NO_SRP)
3059 err:
3060 #endif
3061 #ifndef OPENSSL_NO_ECDH
3062         EVP_PKEY_free(clnt_pub_pkey);
3063         EC_POINT_free(clnt_ecpoint);
3064         if (srvr_ecdh != NULL) 
3065                 EC_KEY_free(srvr_ecdh);
3066         BN_CTX_free(bn_ctx);
3067 #endif
3068         return(-1);
3069         }
3070
3071 int ssl3_get_cert_verify(SSL *s)
3072         {
3073         EVP_PKEY *pkey=NULL;
3074         unsigned char *p;
3075         int al,ok,ret=0;
3076         long n;
3077         int type=0,i,j;
3078         X509 *peer;
3079         const EVP_MD *md = NULL;
3080         EVP_MD_CTX mctx;
3081         EVP_MD_CTX_init(&mctx);
3082
3083         n=s->method->ssl_get_message(s,
3084                 SSL3_ST_SR_CERT_VRFY_A,
3085                 SSL3_ST_SR_CERT_VRFY_B,
3086                 -1,
3087                 516, /* Enough for 4096 bit RSA key with TLS v1.2 */
3088                 &ok);
3089
3090         if (!ok) return((int)n);
3091
3092         if (s->session->peer != NULL)
3093                 {
3094                 peer=s->session->peer;
3095                 pkey=X509_get_pubkey(peer);
3096                 type=X509_certificate_type(peer,pkey);
3097                 }
3098         else
3099                 {
3100                 peer=NULL;
3101                 pkey=NULL;
3102                 }
3103
3104         if (s->s3->tmp.message_type != SSL3_MT_CERTIFICATE_VERIFY)
3105                 {
3106                 s->s3->tmp.reuse_message=1;
3107                 if ((peer != NULL) && (type & EVP_PKT_SIGN))
3108                         {
3109                         al=SSL_AD_UNEXPECTED_MESSAGE;
3110                         SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_MISSING_VERIFY_MESSAGE);
3111                         goto f_err;
3112                         }
3113                 ret=1;
3114                 goto end;
3115                 }
3116
3117         if (peer == NULL)
3118                 {
3119                 SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_NO_CLIENT_CERT_RECEIVED);
3120                 al=SSL_AD_UNEXPECTED_MESSAGE;
3121                 goto f_err;
3122                 }
3123
3124         if (!(type & EVP_PKT_SIGN))
3125                 {
3126                 SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_SIGNATURE_FOR_NON_SIGNING_CERTIFICATE);
3127                 al=SSL_AD_ILLEGAL_PARAMETER;
3128                 goto f_err;
3129                 }
3130
3131         if (s->s3->change_cipher_spec)
3132                 {
3133                 SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_CCS_RECEIVED_EARLY);
3134                 al=SSL_AD_UNEXPECTED_MESSAGE;
3135                 goto f_err;
3136                 }
3137
3138         /* we now have a signature that we need to verify */
3139         p=(unsigned char *)s->init_msg;
3140         /* Check for broken implementations of GOST ciphersuites */
3141         /* If key is GOST and n is exactly 64, it is bare
3142          * signature without length field */
3143         if (n==64 && (pkey->type==NID_id_GostR3410_94 ||
3144                 pkey->type == NID_id_GostR3410_2001) )
3145                 {
3146                 i=64;
3147                 } 
3148         else 
3149                 {       
3150                 if (SSL_USE_SIGALGS(s))
3151                         {
3152                         int rv = tls12_check_peer_sigalg(&md, s, p, pkey);
3153                         if (rv == -1)
3154                                 {
3155                                 al = SSL_AD_INTERNAL_ERROR;
3156                                 goto f_err;
3157                                 }
3158                         else if (rv == 0)
3159                                 {
3160                                 al = SSL_AD_DECODE_ERROR;
3161                                 goto f_err;
3162                                 }
3163 #ifdef SSL_DEBUG
3164 fprintf(stderr, "USING TLSv1.2 HASH %s\n", EVP_MD_name(md));
3165 #endif
3166                         p += 2;
3167                         n -= 2;
3168                         }
3169                 n2s(p,i);
3170                 n-=2;
3171                 if (i > n)
3172                         {
3173                         SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_LENGTH_MISMATCH);
3174                         al=SSL_AD_DECODE_ERROR;
3175                         goto f_err;
3176                         }
3177         }
3178         j=EVP_PKEY_size(pkey);
3179         if ((i > j) || (n > j) || (n <= 0))
3180                 {
3181                 SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_WRONG_SIGNATURE_SIZE);
3182                 al=SSL_AD_DECODE_ERROR;
3183                 goto f_err;
3184                 }
3185
3186         if (SSL_USE_SIGALGS(s))
3187                 {
3188                 long hdatalen = 0;
3189                 void *hdata;
3190                 hdatalen = BIO_get_mem_data(s->s3->handshake_buffer, &hdata);
3191                 if (hdatalen <= 0)
3192                         {
3193                         SSLerr(SSL_F_SSL3_GET_CERT_VERIFY, ERR_R_INTERNAL_ERROR);
3194                         al=SSL_AD_INTERNAL_ERROR;
3195                         goto f_err;
3196                         }
3197 #ifdef SSL_DEBUG
3198                 fprintf(stderr, "Using TLS 1.2 with client verify alg %s\n",
3199                                                         EVP_MD_name(md));
3200 #endif
3201                 if (!EVP_VerifyInit_ex(&mctx, md, NULL)
3202                         || !EVP_VerifyUpdate(&mctx, hdata, hdatalen))
3203                         {
3204                         SSLerr(SSL_F_SSL3_GET_CERT_VERIFY, ERR_R_EVP_LIB);
3205                         al=SSL_AD_INTERNAL_ERROR;
3206                         goto f_err;
3207                         }
3208
3209                 if (EVP_VerifyFinal(&mctx, p , i, pkey) <= 0)
3210                         {
3211                         al=SSL_AD_DECRYPT_ERROR;
3212                         SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_BAD_SIGNATURE);
3213                         goto f_err;
3214                         }
3215                 }
3216         else
3217 #ifndef OPENSSL_NO_RSA 
3218         if (pkey->type == EVP_PKEY_RSA)
3219                 {
3220                 i=RSA_verify(NID_md5_sha1, s->s3->tmp.cert_verify_md,
3221                         MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH, p, i, 
3222                                                         pkey->pkey.rsa);
3223                 if (i < 0)
3224                         {
3225                         al=SSL_AD_DECRYPT_ERROR;
3226                         SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_BAD_RSA_DECRYPT);
3227                         goto f_err;
3228                         }
3229                 if (i == 0)
3230                         {
3231                         al=SSL_AD_DECRYPT_ERROR;
3232                         SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_BAD_RSA_SIGNATURE);
3233                         goto f_err;
3234                         }
3235                 }
3236         else
3237 #endif
3238 #ifndef OPENSSL_NO_DSA
3239                 if (pkey->type == EVP_PKEY_DSA)
3240                 {
3241                 j=DSA_verify(pkey->save_type,
3242                         &(s->s3->tmp.cert_verify_md[MD5_DIGEST_LENGTH]),
3243                         SHA_DIGEST_LENGTH,p,i,pkey->pkey.dsa);
3244                 if (j <= 0)
3245                         {
3246                         /* bad signature */
3247                         al=SSL_AD_DECRYPT_ERROR;
3248                         SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,SSL_R_BAD_DSA_SIGNATURE);
3249                         goto f_err;
3250                         }
3251                 }
3252         else
3253 #endif
3254 #ifndef OPENSSL_NO_ECDSA
3255                 if (pkey->type == EVP_PKEY_EC)
3256                 {
3257                 j=ECDSA_verify(pkey->save_type,
3258                         &(s->s3->tmp.cert_verify_md[MD5_DIGEST_LENGTH]),
3259                         SHA_DIGEST_LENGTH,p,i,pkey->pkey.ec);
3260                 if (j <= 0)
3261                         {
3262                         /* bad signature */
3263                         al=SSL_AD_DECRYPT_ERROR;
3264                         SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,
3265                             SSL_R_BAD_ECDSA_SIGNATURE);
3266                         goto f_err;
3267                         }
3268                 }
3269         else
3270 #endif
3271         if (pkey->type == NID_id_GostR3410_94 || pkey->type == NID_id_GostR3410_2001)
3272                 {   unsigned char signature[64];
3273                         int idx;
3274                         EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new(pkey,NULL);
3275                         EVP_PKEY_verify_init(pctx);
3276                         if (i!=64) {
3277                                 fprintf(stderr,"GOST signature length is %d",i);
3278                         }       
3279                         for (idx=0;idx<64;idx++) {
3280                                 signature[63-idx]=p[idx];
3281                         }       
3282                         j=EVP_PKEY_verify(pctx,signature,64,s->s3->tmp.cert_verify_md,32);
3283                         EVP_PKEY_CTX_free(pctx);
3284                         if (j<=0) 
3285                                 {
3286                                 al=SSL_AD_DECRYPT_ERROR;
3287                                 SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,
3288                                         SSL_R_BAD_ECDSA_SIGNATURE);
3289                                 goto f_err;
3290                                 }       
3291                 }
3292         else    
3293                 {
3294                 SSLerr(SSL_F_SSL3_GET_CERT_VERIFY,ERR_R_INTERNAL_ERROR);
3295                 al=SSL_AD_UNSUPPORTED_CERTIFICATE;
3296                 goto f_err;
3297                 }
3298
3299
3300         ret=1;
3301         if (0)
3302                 {
3303 f_err:
3304                 ssl3_send_alert(s,SSL3_AL_FATAL,al);
3305                 }
3306 end:
3307         if (s->s3->handshake_buffer)
3308                 {
3309                 BIO_free(s->s3->handshake_buffer);
3310                 s->s3->handshake_buffer = NULL;
3311                 s->s3->flags &= ~TLS1_FLAGS_KEEP_HANDSHAKE;
3312                 }
3313         EVP_MD_CTX_cleanup(&mctx);
3314         EVP_PKEY_free(pkey);
3315         return(ret);
3316         }
3317
3318 int ssl3_get_client_certificate(SSL *s)
3319         {
3320         int i,ok,al,ret= -1;
3321         X509 *x=NULL;
3322         unsigned long l,nc,llen,n;
3323         const unsigned char *p,*q;
3324         unsigned char *d;
3325         STACK_OF(X509) *sk=NULL;
3326
3327         n=s->method->ssl_get_message(s,
3328                 SSL3_ST_SR_CERT_A,
3329                 SSL3_ST_SR_CERT_B,
3330                 -1,
3331                 s->max_cert_list,
3332                 &ok);
3333
3334         if (!ok) return((int)n);
3335
3336         if      (s->s3->tmp.message_type == SSL3_MT_CLIENT_KEY_EXCHANGE)
3337                 {
3338                 if (    (s->verify_mode & SSL_VERIFY_PEER) &&
3339                         (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT))
3340                         {
3341                         SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE);
3342                         al=SSL_AD_HANDSHAKE_FAILURE;
3343                         goto f_err;
3344                         }
3345                 /* If tls asked for a client cert, the client must return a 0 list */
3346                 if ((s->version > SSL3_VERSION) && s->s3->tmp.cert_request)
3347                         {
3348                         SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_TLS_PEER_DID_NOT_RESPOND_WITH_CERTIFICATE_LIST);
3349                         al=SSL_AD_UNEXPECTED_MESSAGE;
3350                         goto f_err;
3351                         }
3352                 s->s3->tmp.reuse_message=1;
3353                 return(1);
3354                 }
3355
3356         if (s->s3->tmp.message_type != SSL3_MT_CERTIFICATE)
3357                 {
3358                 al=SSL_AD_UNEXPECTED_MESSAGE;
3359                 SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_WRONG_MESSAGE_TYPE);
3360                 goto f_err;
3361                 }
3362         p=d=(unsigned char *)s->init_msg;
3363
3364         if ((sk=sk_X509_new_null()) == NULL)
3365                 {
3366                 SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,ERR_R_MALLOC_FAILURE);
3367                 goto err;
3368                 }
3369
3370         n2l3(p,llen);
3371         if (llen+3 != n)
3372                 {
3373                 al=SSL_AD_DECODE_ERROR;
3374                 SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_LENGTH_MISMATCH);
3375                 goto f_err;
3376                 }
3377         for (nc=0; nc<llen; )
3378                 {
3379                 n2l3(p,l);
3380                 if ((l+nc+3) > llen)
3381                         {
3382                         al=SSL_AD_DECODE_ERROR;
3383                         SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_CERT_LENGTH_MISMATCH);
3384                         goto f_err;
3385                         }
3386
3387                 q=p;
3388                 x=d2i_X509(NULL,&p,l);
3389                 if (x == NULL)
3390                         {
3391                         SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,ERR_R_ASN1_LIB);
3392                         goto err;
3393                         }
3394                 if (p != (q+l))
3395                         {
3396                         al=SSL_AD_DECODE_ERROR;
3397                         SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_CERT_LENGTH_MISMATCH);
3398                         goto f_err;
3399                         }
3400                 if (!sk_X509_push(sk,x))
3401                         {
3402                         SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,ERR_R_MALLOC_FAILURE);
3403                         goto err;
3404                         }
3405                 x=NULL;
3406                 nc+=l+3;
3407                 }
3408
3409         if (sk_X509_num(sk) <= 0)
3410                 {
3411                 /* TLS does not mind 0 certs returned */
3412                 if (s->version == SSL3_VERSION)
3413                         {
3414                         al=SSL_AD_HANDSHAKE_FAILURE;
3415                         SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_NO_CERTIFICATES_RETURNED);
3416                         goto f_err;
3417                         }
3418                 /* Fail for TLS only if we required a certificate */
3419                 else if ((s->verify_mode & SSL_VERIFY_PEER) &&
3420                          (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT))
3421                         {
3422                         SS