Fix source where indent will not be able to cope
[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 "../crypto/constant_time_locl.h"
158 #include <openssl/buffer.h>
159 #include <openssl/rand.h>
160 #include <openssl/objects.h>
161 #include <openssl/evp.h>
162 #include <openssl/hmac.h>
163 #include <openssl/x509.h>
164 #ifndef OPENSSL_NO_DH
165 #include <openssl/dh.h>
166 #endif
167 #include <openssl/bn.h>
168 #ifndef OPENSSL_NO_KRB5
169 #include <openssl/krb5_asn.h>
170 #endif
171 #include <openssl/md5.h>
172
173 #ifndef OPENSSL_NO_SSL3_METHOD
174 static const SSL_METHOD *ssl3_get_server_method(int ver);
175
176 static const SSL_METHOD *ssl3_get_server_method(int ver)
177         {
178         if (ver == SSL3_VERSION)
179                 return(SSLv3_server_method());
180         else
181                 return(NULL);
182         }
183
184 IMPLEMENT_ssl3_meth_func(SSLv3_server_method,
185                         ssl3_accept,
186                         ssl_undefined_function,
187                         ssl3_get_server_method)
188 #endif
189
190 #ifndef OPENSSL_NO_SRP
191 static int ssl_check_srp_ext_ClientHello(SSL *s, int *al)
192         {
193         int ret = SSL_ERROR_NONE;
194
195         *al = SSL_AD_UNRECOGNIZED_NAME;
196
197         if ((s->s3->tmp.new_cipher->algorithm_mkey & SSL_kSRP) &&
198             (s->srp_ctx.TLS_ext_srp_username_callback != NULL))
199                 {
200                 if(s->srp_ctx.login == NULL)
201                         {
202                         /* RFC 5054 says SHOULD reject, 
203                            we do so if There is no srp login name */
204                         ret = SSL3_AL_FATAL;
205                         *al = SSL_AD_UNKNOWN_PSK_IDENTITY;
206                         }
207                 else
208                         {
209                         ret = SSL_srp_server_param_with_username(s,al);
210                         }
211                 }
212         return ret;
213         }
214 #endif
215
216 int ssl3_accept(SSL *s)
217         {
218         BUF_MEM *buf;
219         unsigned long alg_k,Time=(unsigned long)time(NULL);
220         void (*cb)(const SSL *ssl,int type,int val)=NULL;
221         int ret= -1;
222         int new_state,state,skip=0;
223
224         RAND_add(&Time,sizeof(Time),0);
225         ERR_clear_error();
226         clear_sys_error();
227
228         if (s->info_callback != NULL)
229                 cb=s->info_callback;
230         else if (s->ctx->info_callback != NULL)
231                 cb=s->ctx->info_callback;
232
233         /* init things to blank */
234         s->in_handshake++;
235         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
236
237         if (s->cert == NULL)
238                 {
239                 SSLerr(SSL_F_SSL3_ACCEPT,SSL_R_NO_CERTIFICATE_SET);
240                 return(-1);
241                 }
242
243 #ifndef OPENSSL_NO_HEARTBEATS
244         /* If we're awaiting a HeartbeatResponse, pretend we
245          * already got and don't await it anymore, because
246          * Heartbeats don't make sense during handshakes anyway.
247          */
248         if (s->tlsext_hb_pending)
249                 {
250                 s->tlsext_hb_pending = 0;
251                 s->tlsext_hb_seq++;
252                 }
253 #endif
254
255         for (;;)
256                 {
257                 state=s->state;
258
259                 switch (s->state)
260                         {
261                 case SSL_ST_RENEGOTIATE:
262                         s->renegotiate=1;
263                         /* s->state=SSL_ST_ACCEPT; */
264
265                 case SSL_ST_BEFORE:
266                 case SSL_ST_ACCEPT:
267                 case SSL_ST_BEFORE|SSL_ST_ACCEPT:
268                 case SSL_ST_OK|SSL_ST_ACCEPT:
269
270                         s->server=1;
271                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
272
273                         if ((s->version>>8) != 3)
274                                 {
275                                 SSLerr(SSL_F_SSL3_ACCEPT, ERR_R_INTERNAL_ERROR);
276                                 return -1;
277                                 }
278
279                         if (!ssl_security(s, SSL_SECOP_VERSION, 0,
280                                                         s->version, NULL))
281                                 {
282                                 SSLerr(SSL_F_SSL3_ACCEPT, SSL_R_VERSION_TOO_LOW);
283                                 return -1;
284                                 }
285
286                         s->type=SSL_ST_ACCEPT;
287
288                         if (s->init_buf == NULL)
289                                 {
290                                 if ((buf=BUF_MEM_new()) == NULL)
291                                         {
292                                         ret= -1;
293                                         goto end;
294                                         }
295                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
296                                         {
297                                         BUF_MEM_free(buf);
298                                         ret= -1;
299                                         goto end;
300                                         }
301                                 s->init_buf=buf;
302                                 }
303
304                         if (!ssl3_setup_buffers(s))
305                                 {
306                                 ret= -1;
307                                 goto end;
308                                 }
309
310                         s->init_num=0;
311                         s->s3->flags &= ~TLS1_FLAGS_SKIP_CERT_VERIFY;
312                         s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
313                         /* Should have been reset by ssl3_get_finished, too. */
314                         s->s3->change_cipher_spec = 0;
315
316                         if (s->state != SSL_ST_RENEGOTIATE)
317                                 {
318                                 /* Ok, we now need to push on a buffering BIO so that
319                                  * the output is sent in a way that TCP likes :-)
320                                  */
321                                 if (!ssl_init_wbio_buffer(s,1)) { ret= -1; goto end; }
322                                 
323                                 ssl3_init_finished_mac(s);
324                                 s->state=SSL3_ST_SR_CLNT_HELLO_A;
325                                 s->ctx->stats.sess_accept++;
326                                 }
327                         else if (!s->s3->send_connection_binding &&
328                                 !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
329                                 {
330                                 /* Server attempting to renegotiate with
331                                  * client that doesn't support secure
332                                  * renegotiation.
333                                  */
334                                 SSLerr(SSL_F_SSL3_ACCEPT, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
335                                 ssl3_send_alert(s,SSL3_AL_FATAL,SSL_AD_HANDSHAKE_FAILURE);
336                                 ret = -1;
337                                 goto end;
338                                 }
339                         else
340                                 {
341                                 /* s->state == SSL_ST_RENEGOTIATE,
342                                  * we will just send a HelloRequest */
343                                 s->ctx->stats.sess_accept_renegotiate++;
344                                 s->state=SSL3_ST_SW_HELLO_REQ_A;
345                                 }
346                         break;
347
348                 case SSL3_ST_SW_HELLO_REQ_A:
349                 case SSL3_ST_SW_HELLO_REQ_B:
350
351                         s->shutdown=0;
352                         ret=ssl3_send_hello_request(s);
353                         if (ret <= 0) goto end;
354                         s->s3->tmp.next_state=SSL3_ST_SW_HELLO_REQ_C;
355                         s->state=SSL3_ST_SW_FLUSH;
356                         s->init_num=0;
357
358                         ssl3_init_finished_mac(s);
359                         break;
360
361                 case SSL3_ST_SW_HELLO_REQ_C:
362                         s->state=SSL_ST_OK;
363                         break;
364
365                 case SSL3_ST_SR_CLNT_HELLO_A:
366                 case SSL3_ST_SR_CLNT_HELLO_B:
367                 case SSL3_ST_SR_CLNT_HELLO_C:
368
369                         ret=ssl3_get_client_hello(s);
370                         if (ret <= 0) goto end;
371 #ifndef OPENSSL_NO_SRP
372                         s->state = SSL3_ST_SR_CLNT_HELLO_D;
373                 case SSL3_ST_SR_CLNT_HELLO_D:
374                         {
375                         int al;
376                         if ((ret = ssl_check_srp_ext_ClientHello(s,&al))  < 0)
377                                         {
378                                         /* callback indicates firther work to be done */
379                                         s->rwstate=SSL_X509_LOOKUP;
380                                         goto end;
381                                         }
382                         if (ret != SSL_ERROR_NONE)
383                                 {
384                                 ssl3_send_alert(s,SSL3_AL_FATAL,al);    
385                                 /* This is not really an error but the only means to
386                                    for a client to detect whether srp is supported. */
387                                    if (al != TLS1_AD_UNKNOWN_PSK_IDENTITY)      
388                                         SSLerr(SSL_F_SSL3_ACCEPT,SSL_R_CLIENTHELLO_TLSEXT);                     
389                                 ret = SSL_TLSEXT_ERR_ALERT_FATAL;                       
390                                 ret= -1;
391                                 goto end;       
392                                 }
393                         }
394 #endif          
395                         
396                         s->renegotiate = 2;
397                         s->state=SSL3_ST_SW_SRVR_HELLO_A;
398                         s->init_num=0;
399                         break;
400
401                 case SSL3_ST_SW_SRVR_HELLO_A:
402                 case SSL3_ST_SW_SRVR_HELLO_B:
403                         ret=ssl3_send_server_hello(s);
404                         if (ret <= 0) goto end;
405 #ifndef OPENSSL_NO_TLSEXT
406                         if (s->hit)
407                                 {
408                                 if (s->tlsext_ticket_expected)
409                                         s->state=SSL3_ST_SW_SESSION_TICKET_A;
410                                 else
411                                         s->state=SSL3_ST_SW_CHANGE_A;
412                                 }
413 #else
414                         if (s->hit)
415                                         s->state=SSL3_ST_SW_CHANGE_A;
416 #endif
417                         else
418                                         s->state = SSL3_ST_SW_CERT_A;
419                         s->init_num = 0;
420                         break;
421
422                 case SSL3_ST_SW_CERT_A:
423                 case SSL3_ST_SW_CERT_B:
424                         /* Check if it is anon DH or anon ECDH, */
425                         /* normal PSK or KRB5 or SRP */
426                         if (!(s->s3->tmp.new_cipher->algorithm_auth & (SSL_aNULL|SSL_aKRB5|SSL_aSRP))
427                                 && !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
428                                 {
429                                 ret=ssl3_send_server_certificate(s);
430                                 if (ret <= 0) goto end;
431 #ifndef OPENSSL_NO_TLSEXT
432                                 if (s->tlsext_status_expected)
433                                         s->state=SSL3_ST_SW_CERT_STATUS_A;
434                                 else
435                                         s->state=SSL3_ST_SW_KEY_EXCH_A;
436                                 }
437                         else
438                                 {
439                                 skip = 1;
440                                 s->state=SSL3_ST_SW_KEY_EXCH_A;
441                                 }
442 #else
443                                 }
444                         else
445                                 skip=1;
446
447                         s->state=SSL3_ST_SW_KEY_EXCH_A;
448 #endif
449                         s->init_num=0;
450                         break;
451
452                 case SSL3_ST_SW_KEY_EXCH_A:
453                 case SSL3_ST_SW_KEY_EXCH_B:
454                         alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
455
456                         /*
457                          * clear this, it may get reset by
458                          * send_server_key_exchange
459                          */
460                         s->s3->tmp.use_rsa_tmp=0;
461
462
463                         /* only send if a DH key exchange, fortezza or
464                          * RSA but we have a sign only certificate
465                          *
466                          * PSK: may send PSK identity hints
467                          *
468                          * For ECC ciphersuites, we send a serverKeyExchange
469                          * message only if the cipher suite is either
470                          * ECDH-anon or ECDHE. In other cases, the
471                          * server certificate contains the server's
472                          * public key for key exchange.
473                          */
474                         if (0
475                         /* PSK: send ServerKeyExchange if PSK identity
476                          * hint if provided */
477 #ifndef OPENSSL_NO_PSK
478                             || ((alg_k & SSL_kPSK) && s->ctx->psk_identity_hint)
479 #endif
480 #ifndef OPENSSL_NO_SRP
481                             /* SRP: send ServerKeyExchange */
482                             || (alg_k & SSL_kSRP)
483 #endif
484                             || (alg_k & SSL_kDHE)
485                             || (alg_k & SSL_kECDHE)
486                             || ((alg_k & SSL_kRSA)
487                                 && (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
488                                     || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
489                                         && EVP_PKEY_size(s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey)*8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
490                                         )
491                                     )
492                                 )
493                             )
494                                 {
495                                 ret=ssl3_send_server_key_exchange(s);
496                                 if (ret <= 0) goto end;
497                                 }
498                         else
499                                 skip=1;
500
501                         s->state=SSL3_ST_SW_CERT_REQ_A;
502                         s->init_num=0;
503                         break;
504
505                 case SSL3_ST_SW_CERT_REQ_A:
506                 case SSL3_ST_SW_CERT_REQ_B:
507                         if (/* don't request cert unless asked for it: */
508                                 !(s->verify_mode & SSL_VERIFY_PEER) ||
509                                 /* if SSL_VERIFY_CLIENT_ONCE is set,
510                                  * don't request cert during re-negotiation: */
511                                 ((s->session->peer != NULL) &&
512                                  (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
513                                 /* never request cert in anonymous ciphersuites
514                                  * (see section "Certificate request" in SSL 3 drafts
515                                  * and in RFC 2246): */
516                                 ((s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) &&
517                                  /* ... except when the application insists on verification
518                                   * (against the specs, but s3_clnt.c accepts this for SSL 3) */
519                                  !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) ||
520                                  /* never request cert in Kerberos ciphersuites */
521                                 (s->s3->tmp.new_cipher->algorithm_auth & SSL_aKRB5) ||
522                                 /* don't request certificate for SRP auth */
523                                 (s->s3->tmp.new_cipher->algorithm_auth & SSL_aSRP)
524                                 /* With normal PSK Certificates and
525                                  * Certificate Requests are omitted */
526                                 || (s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
527                                 {
528                                 /* no cert request */
529                                 skip=1;
530                                 s->s3->tmp.cert_request=0;
531                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
532                                 if (s->s3->handshake_buffer)
533                                         if (!ssl3_digest_cached_records(s))
534                                                 return -1;
535                                 }
536                         else
537                                 {
538                                 s->s3->tmp.cert_request=1;
539                                 ret=ssl3_send_certificate_request(s);
540                                 if (ret <= 0) goto end;
541 #ifndef NETSCAPE_HANG_BUG
542                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
543 #else
544                                 s->state=SSL3_ST_SW_FLUSH;
545                                 s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
546 #endif
547                                 s->init_num=0;
548                                 }
549                         break;
550
551                 case SSL3_ST_SW_SRVR_DONE_A:
552                 case SSL3_ST_SW_SRVR_DONE_B:
553                         ret=ssl3_send_server_done(s);
554                         if (ret <= 0) goto end;
555                         s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
556                         s->state=SSL3_ST_SW_FLUSH;
557                         s->init_num=0;
558                         break;
559                 
560                 case SSL3_ST_SW_FLUSH:
561
562                         /* This code originally checked to see if
563                          * any data was pending using BIO_CTRL_INFO
564                          * and then flushed. This caused problems
565                          * as documented in PR#1939. The proposed
566                          * fix doesn't completely resolve this issue
567                          * as buggy implementations of BIO_CTRL_PENDING
568                          * still exist. So instead we just flush
569                          * unconditionally.
570                          */
571
572                         s->rwstate=SSL_WRITING;
573                         if (BIO_flush(s->wbio) <= 0)
574                                 {
575                                 ret= -1;
576                                 goto end;
577                                 }
578                         s->rwstate=SSL_NOTHING;
579
580                         s->state=s->s3->tmp.next_state;
581                         break;
582
583                 case SSL3_ST_SR_CERT_A:
584                 case SSL3_ST_SR_CERT_B:
585                         if (s->s3->tmp.cert_request)
586                                 {
587                                 ret=ssl3_get_client_certificate(s);
588                                 if (ret <= 0) goto end;
589                                 }
590                         s->init_num=0;
591                         s->state=SSL3_ST_SR_KEY_EXCH_A;
592                         break;
593
594                 case SSL3_ST_SR_KEY_EXCH_A:
595                 case SSL3_ST_SR_KEY_EXCH_B:
596                         ret=ssl3_get_client_key_exchange(s);
597                         if (ret <= 0)
598                                 goto end;
599                         if (ret == 2)
600                                 {
601                                 /* For the ECDH ciphersuites when
602                                  * the client sends its ECDH pub key in
603                                  * a certificate, the CertificateVerify
604                                  * message is not sent.
605                                  * Also for GOST ciphersuites when
606                                  * the client uses its key from the certificate
607                                  * for key exchange.
608                                  */
609 #if defined(OPENSSL_NO_TLSEXT) || defined(OPENSSL_NO_NEXTPROTONEG)
610                                 s->state=SSL3_ST_SR_FINISHED_A;
611 #else
612                                 if (s->s3->next_proto_neg_seen)
613                                         s->state=SSL3_ST_SR_NEXT_PROTO_A;
614                                 else
615                                         s->state=SSL3_ST_SR_FINISHED_A;
616 #endif
617                                 s->init_num = 0;
618                                 }
619                         else if (SSL_USE_SIGALGS(s))
620                                 {
621                                 s->state=SSL3_ST_SR_CERT_VRFY_A;
622                                 s->init_num=0;
623                                 if (!s->session->peer)
624                                         break;
625                                 /* For sigalgs freeze the handshake buffer
626                                  * at this point and digest cached records.
627                                  */
628                                 if (!s->s3->handshake_buffer)
629                                         {
630                                         SSLerr(SSL_F_SSL3_ACCEPT,ERR_R_INTERNAL_ERROR);
631                                         return -1;
632                                         }
633                                 s->s3->flags |= TLS1_FLAGS_KEEP_HANDSHAKE;
634                                 if (!ssl3_digest_cached_records(s))
635                                         return -1;
636                                 }
637                         else
638                                 {
639                                 int offset=0;
640                                 int dgst_num;
641
642                                 s->state=SSL3_ST_SR_CERT_VRFY_A;
643                                 s->init_num=0;
644
645                                 /* We need to get hashes here so if there is
646                                  * a client cert, it can be verified
647                                  * FIXME - digest processing for CertificateVerify
648                                  * should be generalized. But it is next step
649                                  */
650                                 if (s->s3->handshake_buffer)
651                                         if (!ssl3_digest_cached_records(s))
652                                                 return -1;
653                                 for (dgst_num=0; dgst_num<SSL_MAX_DIGEST;dgst_num++)    
654                                         if (s->s3->handshake_dgst[dgst_num]) 
655                                                 {
656                                                 int dgst_size;
657
658                                                 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]));
659                                                 dgst_size=EVP_MD_CTX_size(s->s3->handshake_dgst[dgst_num]);
660                                                 if (dgst_size < 0)
661                                                         {
662                                                         ret = -1;
663                                                         goto end;
664                                                         }
665                                                 offset+=dgst_size;
666                                                 }               
667                                 }
668                         break;
669
670                 case SSL3_ST_SR_CERT_VRFY_A:
671                 case SSL3_ST_SR_CERT_VRFY_B:
672                         /*
673                          * This *should* be the first time we enable CCS, but be
674                          * extra careful about surrounding code changes. We need
675                          * to set this here because we don't know if we're
676                          * expecting a CertificateVerify or not.
677                          */
678                         if (!s->s3->change_cipher_spec)
679                                 s->s3->flags |= SSL3_FLAGS_CCS_OK;
680                         /* we should decide if we expected this one */
681                         ret=ssl3_get_cert_verify(s);
682                         if (ret <= 0) goto end;
683
684 #if defined(OPENSSL_NO_TLSEXT) || defined(OPENSSL_NO_NEXTPROTONEG)
685                         s->state=SSL3_ST_SR_FINISHED_A;
686 #else
687                         if (s->s3->next_proto_neg_seen)
688                                 s->state=SSL3_ST_SR_NEXT_PROTO_A;
689                         else
690                                 s->state=SSL3_ST_SR_FINISHED_A;
691 #endif
692                         s->init_num=0;
693                         break;
694
695 #if !defined(OPENSSL_NO_TLSEXT) && !defined(OPENSSL_NO_NEXTPROTONEG)
696                 case SSL3_ST_SR_NEXT_PROTO_A:
697                 case SSL3_ST_SR_NEXT_PROTO_B:
698                         /*
699                          * Enable CCS for resumed handshakes with NPN.
700                          * In a full handshake with NPN, we end up here through
701                          * SSL3_ST_SR_CERT_VRFY_B, where SSL3_FLAGS_CCS_OK was
702                          * already set. Receiving a CCS clears the flag, so make
703                          * sure not to re-enable it to ban duplicates.
704                          * s->s3->change_cipher_spec is set when a CCS is
705                          * processed in s3_pkt.c, and remains set until
706                          * the client's Finished message is read.
707                          */
708                         if (!s->s3->change_cipher_spec)
709                                 s->s3->flags |= SSL3_FLAGS_CCS_OK;
710
711                         ret=ssl3_get_next_proto(s);
712                         if (ret <= 0) goto end;
713                         s->init_num = 0;
714                         s->state=SSL3_ST_SR_FINISHED_A;
715                         break;
716 #endif
717
718                 case SSL3_ST_SR_FINISHED_A:
719                 case SSL3_ST_SR_FINISHED_B:
720                         /*
721                          * Enable CCS for resumed handshakes without NPN.
722                          * In a full handshake, we end up here through
723                          * SSL3_ST_SR_CERT_VRFY_B, where SSL3_FLAGS_CCS_OK was
724                          * already set. Receiving a CCS clears the flag, so make
725                          * sure not to re-enable it to ban duplicates.
726                          * s->s3->change_cipher_spec is set when a CCS is
727                          * processed in s3_pkt.c, and remains set until
728                          * the client's Finished message is read.
729                          */
730                         if (!s->s3->change_cipher_spec)
731                                 s->s3->flags |= SSL3_FLAGS_CCS_OK;
732                         ret=ssl3_get_finished(s,SSL3_ST_SR_FINISHED_A,
733                                 SSL3_ST_SR_FINISHED_B);
734                         if (ret <= 0) goto end;
735                         if (s->hit)
736                                 s->state=SSL_ST_OK;
737 #ifndef OPENSSL_NO_TLSEXT
738                         else if (s->tlsext_ticket_expected)
739                                 s->state=SSL3_ST_SW_SESSION_TICKET_A;
740 #endif
741                         else
742                                 s->state=SSL3_ST_SW_CHANGE_A;
743                         s->init_num=0;
744                         break;
745
746 #ifndef OPENSSL_NO_TLSEXT
747                 case SSL3_ST_SW_SESSION_TICKET_A:
748                 case SSL3_ST_SW_SESSION_TICKET_B:
749                         ret=ssl3_send_newsession_ticket(s);
750                         if (ret <= 0) goto end;
751                         s->state=SSL3_ST_SW_CHANGE_A;
752                         s->init_num=0;
753                         break;
754
755                 case SSL3_ST_SW_CERT_STATUS_A:
756                 case SSL3_ST_SW_CERT_STATUS_B:
757                         ret=ssl3_send_cert_status(s);
758                         if (ret <= 0) goto end;
759                         s->state=SSL3_ST_SW_KEY_EXCH_A;
760                         s->init_num=0;
761                         break;
762
763 #endif
764
765                 case SSL3_ST_SW_CHANGE_A:
766                 case SSL3_ST_SW_CHANGE_B:
767
768                         s->session->cipher=s->s3->tmp.new_cipher;
769                         if (!s->method->ssl3_enc->setup_key_block(s))
770                                 { ret= -1; goto end; }
771
772                         ret=ssl3_send_change_cipher_spec(s,
773                                 SSL3_ST_SW_CHANGE_A,SSL3_ST_SW_CHANGE_B);
774
775                         if (ret <= 0) goto end;
776                         s->state=SSL3_ST_SW_FINISHED_A;
777                         s->init_num=0;
778
779                         if (!s->method->ssl3_enc->change_cipher_state(s,
780                                 SSL3_CHANGE_CIPHER_SERVER_WRITE))
781                                 {
782                                 ret= -1;
783                                 goto end;
784                                 }
785
786                         break;
787
788                 case SSL3_ST_SW_FINISHED_A:
789                 case SSL3_ST_SW_FINISHED_B:
790                         ret=ssl3_send_finished(s,
791                                 SSL3_ST_SW_FINISHED_A,SSL3_ST_SW_FINISHED_B,
792                                 s->method->ssl3_enc->server_finished_label,
793                                 s->method->ssl3_enc->server_finished_label_len);
794                         if (ret <= 0) goto end;
795                         s->state=SSL3_ST_SW_FLUSH;
796                         if (s->hit)
797                                 {
798 #if defined(OPENSSL_NO_TLSEXT) || defined(OPENSSL_NO_NEXTPROTONEG)
799                                 s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
800 #else
801                                 if (s->s3->next_proto_neg_seen)
802                                         {
803                                         s->s3->tmp.next_state=SSL3_ST_SR_NEXT_PROTO_A;
804                                         }
805                                 else
806                                         s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
807 #endif
808                                 }
809                         else
810                                 s->s3->tmp.next_state=SSL_ST_OK;
811                         s->init_num=0;
812                         break;
813
814                 case SSL_ST_OK:
815                         /* clean a few things up */
816                         ssl3_cleanup_key_block(s);
817
818                         BUF_MEM_free(s->init_buf);
819                         s->init_buf=NULL;
820
821                         /* remove buffering on output */
822                         ssl_free_wbio_buffer(s);
823
824                         s->init_num=0;
825
826                         if (s->renegotiate == 2) /* skipped if we just sent a HelloRequest */
827                                 {
828                                 s->renegotiate=0;
829                                 s->new_session=0;
830                                 
831                                 ssl_update_cache(s,SSL_SESS_CACHE_SERVER);
832                                 
833                                 s->ctx->stats.sess_accept_good++;
834                                 /* s->server=1; */
835                                 s->handshake_func=ssl3_accept;
836
837                                 if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
838                                 }
839                         
840                         ret = 1;
841                         goto end;
842                         /* break; */
843
844                 default:
845                         SSLerr(SSL_F_SSL3_ACCEPT,SSL_R_UNKNOWN_STATE);
846                         ret= -1;
847                         goto end;
848                         /* break; */
849                         }
850                 
851                 if (!s->s3->tmp.reuse_message && !skip)
852                         {
853                         if (s->debug)
854                                 {
855                                 if ((ret=BIO_flush(s->wbio)) <= 0)
856                                         goto end;
857                                 }
858
859
860                         if ((cb != NULL) && (s->state != state))
861                                 {
862                                 new_state=s->state;
863                                 s->state=state;
864                                 cb(s,SSL_CB_ACCEPT_LOOP,1);
865                                 s->state=new_state;
866                                 }
867                         }
868                 skip=0;
869                 }
870 end:
871         /* BIO_flush(s->wbio); */
872
873         s->in_handshake--;
874         if (cb != NULL)
875                 cb(s,SSL_CB_ACCEPT_EXIT,ret);
876         return(ret);
877         }
878
879 int ssl3_send_hello_request(SSL *s)
880         {
881
882         if (s->state == SSL3_ST_SW_HELLO_REQ_A)
883                 {
884                 ssl_set_handshake_header(s, SSL3_MT_HELLO_REQUEST, 0);
885                 s->state=SSL3_ST_SW_HELLO_REQ_B;
886                 }
887
888         /* SSL3_ST_SW_HELLO_REQ_B */
889         return ssl_do_write(s);
890         }
891
892 int ssl3_get_client_hello(SSL *s)
893         {
894         int i,j,ok,al=SSL_AD_INTERNAL_ERROR,ret= -1;
895         unsigned int cookie_len;
896         long n;
897         unsigned long id;
898         unsigned char *p,*d;
899         SSL_CIPHER *c;
900 #ifndef OPENSSL_NO_COMP
901         unsigned char *q;
902         SSL_COMP *comp=NULL;
903 #endif
904         STACK_OF(SSL_CIPHER) *ciphers=NULL;
905
906         if (s->state == SSL3_ST_SR_CLNT_HELLO_C && !s->first_packet)
907                 goto retry_cert;
908
909         /* We do this so that we will respond with our native type.
910          * If we are TLSv1 and we get SSLv3, we will respond with TLSv1,
911          * This down switching should be handled by a different method.
912          * If we are SSLv3, we will respond with SSLv3, even if prompted with
913          * TLSv1.
914          */
915         if (s->state == SSL3_ST_SR_CLNT_HELLO_A
916                 )
917                 {
918                 s->state=SSL3_ST_SR_CLNT_HELLO_B;
919                 }
920         s->first_packet=1;
921         n=s->method->ssl_get_message(s,
922                 SSL3_ST_SR_CLNT_HELLO_B,
923                 SSL3_ST_SR_CLNT_HELLO_C,
924                 SSL3_MT_CLIENT_HELLO,
925                 SSL3_RT_MAX_PLAIN_LENGTH,
926                 &ok);
927
928         if (!ok) return((int)n);
929         s->first_packet=0;
930         d=p=(unsigned char *)s->init_msg;
931
932         /* use version from inside client hello, not from record header
933          * (may differ: see RFC 2246, Appendix E, second paragraph) */
934         s->client_version=(((int)p[0])<<8)|(int)p[1];
935         p+=2;
936
937         if (SSL_IS_DTLS(s)  ?   (s->client_version > s->version &&
938                                  s->method->version != DTLS_ANY_VERSION)
939                             :   (s->client_version < s->version))
940                 {
941                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_WRONG_VERSION_NUMBER);
942                 if ((s->client_version>>8) == SSL3_VERSION_MAJOR &&
943                         !s->enc_write_ctx && !s->write_hash)
944                         {
945                         /* similar to ssl3_get_record, send alert using remote version number */
946                         s->version = s->client_version;
947                         }
948                 al = SSL_AD_PROTOCOL_VERSION;
949                 goto f_err;
950                 }
951
952         /* If we require cookies and this ClientHello doesn't
953          * contain one, just return since we do not want to
954          * allocate any memory yet. So check cookie length...
955          */
956         if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE)
957                 {
958                 unsigned int session_length, cookie_length;
959                 
960                 session_length = *(p + SSL3_RANDOM_SIZE);
961                 cookie_length = *(p + SSL3_RANDOM_SIZE + session_length + 1);
962
963                 if (cookie_length == 0)
964                         return 1;
965                 }
966
967         /* load the client random */
968         memcpy(s->s3->client_random,p,SSL3_RANDOM_SIZE);
969         p+=SSL3_RANDOM_SIZE;
970
971         /* get the session-id */
972         j= *(p++);
973
974         s->hit=0;
975         /* Versions before 0.9.7 always allow clients to resume sessions in renegotiation.
976          * 0.9.7 and later allow this by default, but optionally ignore resumption requests
977          * with flag SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION (it's a new flag rather
978          * than a change to default behavior so that applications relying on this for security
979          * won't even compile against older library versions).
980          *
981          * 1.0.1 and later also have a function SSL_renegotiate_abbreviated() to request
982          * renegotiation but not a new session (s->new_session remains unset): for servers,
983          * this essentially just means that the SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION
984          * setting will be ignored.
985          */
986         if ((s->new_session && (s->options & SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION)))
987                 {
988                 if (!ssl_get_new_session(s,1))
989                         goto err;
990                 }
991         else
992                 {
993                 i=ssl_get_prev_session(s, p, j, d + n);
994                 /*
995                  * Only resume if the session's version matches the negotiated
996                  * version.
997                  * RFC 5246 does not provide much useful advice on resumption
998                  * with a different protocol version. It doesn't forbid it but
999                  * the sanity of such behaviour would be questionable.
1000                  * In practice, clients do not accept a version mismatch and
1001                  * will abort the handshake with an error.
1002                  */
1003                 if (i == 1 && s->version == s->session->ssl_version)
1004                         { /* previous session */
1005                         s->hit=1;
1006                         }
1007                 else if (i == -1)
1008                         goto err;
1009                 else /* i == 0 */
1010                         {
1011                         if (!ssl_get_new_session(s,1))
1012                                 goto err;
1013                         }
1014                 }
1015
1016         p+=j;
1017
1018         if (SSL_IS_DTLS(s))
1019                 {
1020                 /* cookie stuff */
1021                 cookie_len = *(p++);
1022
1023                 /* 
1024                  * The ClientHello may contain a cookie even if the
1025                  * HelloVerify message has not been sent--make sure that it
1026                  * does not cause an overflow.
1027                  */
1028                 if ( cookie_len > sizeof(s->d1->rcvd_cookie))
1029                         {
1030                         /* too much data */
1031                         al = SSL_AD_DECODE_ERROR;
1032                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_COOKIE_MISMATCH);
1033                         goto f_err;
1034                         }
1035
1036                 /* verify the cookie if appropriate option is set. */
1037                 if ((SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) &&
1038                         cookie_len > 0)
1039                         {
1040                         memcpy(s->d1->rcvd_cookie, p, cookie_len);
1041
1042                         if ( s->ctx->app_verify_cookie_cb != NULL)
1043                                 {
1044                                 if ( s->ctx->app_verify_cookie_cb(s, s->d1->rcvd_cookie,
1045                                         cookie_len) == 0)
1046                                         {
1047                                         al=SSL_AD_HANDSHAKE_FAILURE;
1048                                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, 
1049                                                 SSL_R_COOKIE_MISMATCH);
1050                                         goto f_err;
1051                                         }
1052                                 /* else cookie verification succeeded */
1053                                 }
1054                         /* default verification */
1055                         else if ( memcmp(s->d1->rcvd_cookie, s->d1->cookie, 
1056                                                   s->d1->cookie_len) != 0)
1057                                 {
1058                                         al=SSL_AD_HANDSHAKE_FAILURE;
1059                                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, 
1060                                                 SSL_R_COOKIE_MISMATCH);
1061                                         goto f_err;
1062                                 }
1063                         /* Set to -2 so if successful we return 2 */
1064                         ret = -2;
1065                         }
1066
1067                 p += cookie_len;
1068                 if (s->method->version == DTLS_ANY_VERSION)
1069                         {
1070                         /* Select version to use */
1071                         if (s->client_version <= DTLS1_2_VERSION &&
1072                                 !(s->options & SSL_OP_NO_DTLSv1_2))
1073                                 {
1074                                 s->version = DTLS1_2_VERSION;
1075                                 s->method = DTLSv1_2_server_method();
1076                                 }
1077                         else if (tls1_suiteb(s))
1078                                 {
1079                                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_ONLY_DTLS_1_2_ALLOWED_IN_SUITEB_MODE);
1080                                 s->version = s->client_version;
1081                                 al = SSL_AD_PROTOCOL_VERSION;
1082                                 goto f_err;
1083                                 }
1084                         else if (s->client_version <= DTLS1_VERSION &&
1085                                 !(s->options & SSL_OP_NO_DTLSv1))
1086                                 {
1087                                 s->version = DTLS1_VERSION;
1088                                 s->method = DTLSv1_server_method();
1089                                 }
1090                         else
1091                                 {
1092                                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_WRONG_VERSION_NUMBER);
1093                                 s->version = s->client_version;
1094                                 al = SSL_AD_PROTOCOL_VERSION;
1095                                 goto f_err;
1096                                 }
1097                         s->session->ssl_version = s->version;
1098                         }
1099                 }
1100
1101         n2s(p,i);
1102         if ((i == 0) && (j != 0))
1103                 {
1104                 /* we need a cipher if we are not resuming a session */
1105                 al=SSL_AD_ILLEGAL_PARAMETER;
1106                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_NO_CIPHERS_SPECIFIED);
1107                 goto f_err;
1108                 }
1109         if ((p+i) >= (d+n))
1110                 {
1111                 /* not enough data */
1112                 al=SSL_AD_DECODE_ERROR;
1113                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_LENGTH_MISMATCH);
1114                 goto f_err;
1115                 }
1116         if ((i > 0) && (ssl_bytes_to_cipher_list(s,p,i,&(ciphers))
1117                 == NULL))
1118                 {
1119                 goto err;
1120                 }
1121         p+=i;
1122
1123         /* If it is a hit, check that the cipher is in the list */
1124         if ((s->hit) && (i > 0))
1125                 {
1126                 j=0;
1127                 id=s->session->cipher->id;
1128
1129 #ifdef CIPHER_DEBUG
1130                 fprintf(stderr,"client sent %d ciphers\n",sk_SSL_CIPHER_num(ciphers));
1131 #endif
1132                 for (i=0; i<sk_SSL_CIPHER_num(ciphers); i++)
1133                         {
1134                         c=sk_SSL_CIPHER_value(ciphers,i);
1135 #ifdef CIPHER_DEBUG
1136                         fprintf(stderr,"client [%2d of %2d]:%s\n",
1137                                 i,sk_SSL_CIPHER_num(ciphers),
1138                                 SSL_CIPHER_get_name(c));
1139 #endif
1140                         if (c->id == id)
1141                                 {
1142                                 j=1;
1143                                 break;
1144                                 }
1145                         }
1146 /* Disabled because it can be used in a ciphersuite downgrade
1147  * attack: CVE-2010-4180.
1148  */
1149 #if 0
1150                 if (j == 0 && (s->options & SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG) && (sk_SSL_CIPHER_num(ciphers) == 1))
1151                         {
1152                         /* Special case as client bug workaround: the previously used cipher may
1153                          * not be in the current list, the client instead might be trying to
1154                          * continue using a cipher that before wasn't chosen due to server
1155                          * preferences.  We'll have to reject the connection if the cipher is not
1156                          * enabled, though. */
1157                         c = sk_SSL_CIPHER_value(ciphers, 0);
1158                         if (sk_SSL_CIPHER_find(SSL_get_ciphers(s), c) >= 0)
1159                                 {
1160                                 s->session->cipher = c;
1161                                 j = 1;
1162                                 }
1163                         }
1164 #endif
1165                 if (j == 0)
1166                         {
1167                         /* we need to have the cipher in the cipher
1168                          * list if we are asked to reuse it */
1169                         al=SSL_AD_ILLEGAL_PARAMETER;
1170                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_REQUIRED_CIPHER_MISSING);
1171                         goto f_err;
1172                         }
1173                 }
1174
1175         /* compression */
1176         i= *(p++);
1177         if ((p+i) > (d+n))
1178                 {
1179                 /* not enough data */
1180                 al=SSL_AD_DECODE_ERROR;
1181                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_LENGTH_MISMATCH);
1182                 goto f_err;
1183                 }
1184 #ifndef OPENSSL_NO_COMP
1185         q=p;
1186 #endif
1187         for (j=0; j<i; j++)
1188                 {
1189                 if (p[j] == 0) break;
1190                 }
1191
1192         p+=i;
1193         if (j >= i)
1194                 {
1195                 /* no compress */
1196                 al=SSL_AD_DECODE_ERROR;
1197                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_NO_COMPRESSION_SPECIFIED);
1198                 goto f_err;
1199                 }
1200
1201 #ifndef OPENSSL_NO_TLSEXT
1202         /* TLS extensions*/
1203         if (s->version >= SSL3_VERSION)
1204                 {
1205                 if (!ssl_parse_clienthello_tlsext(s,&p,d,n))
1206                         {
1207                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_PARSE_TLSEXT);
1208                         goto err;
1209                         }
1210                 }
1211
1212         /* Check if we want to use external pre-shared secret for this
1213          * handshake for not reused session only. We need to generate
1214          * server_random before calling tls_session_secret_cb in order to allow
1215          * SessionTicket processing to use it in key derivation. */
1216         {
1217                 unsigned char *pos;
1218                 pos=s->s3->server_random;
1219                 if (ssl_fill_hello_random(s, 1, pos, SSL3_RANDOM_SIZE) <= 0)
1220                         {
1221                         goto f_err;
1222                         }
1223         }
1224
1225         if (!s->hit && s->version >= TLS1_VERSION && s->tls_session_secret_cb)
1226                 {
1227                 SSL_CIPHER *pref_cipher=NULL;
1228
1229                 s->session->master_key_length=sizeof(s->session->master_key);
1230                 if(s->tls_session_secret_cb(s, s->session->master_key, &s->session->master_key_length,
1231                         ciphers, &pref_cipher, s->tls_session_secret_cb_arg))
1232                         {
1233                         s->hit=1;
1234                         s->session->ciphers=ciphers;
1235                         s->session->verify_result=X509_V_OK;
1236
1237                         ciphers=NULL;
1238
1239                         /* check if some cipher was preferred by call back */
1240                         pref_cipher=pref_cipher ? pref_cipher : ssl3_choose_cipher(s, s->session->ciphers, SSL_get_ciphers(s));
1241                         if (pref_cipher == NULL)
1242                                 {
1243                                 al=SSL_AD_HANDSHAKE_FAILURE;
1244                                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_NO_SHARED_CIPHER);
1245                                 goto f_err;
1246                                 }
1247
1248                         s->session->cipher=pref_cipher;
1249
1250                         if (s->cipher_list)
1251                                 sk_SSL_CIPHER_free(s->cipher_list);
1252
1253                         if (s->cipher_list_by_id)
1254                                 sk_SSL_CIPHER_free(s->cipher_list_by_id);
1255
1256                         s->cipher_list = sk_SSL_CIPHER_dup(s->session->ciphers);
1257                         s->cipher_list_by_id = sk_SSL_CIPHER_dup(s->session->ciphers);
1258                         }
1259                 }
1260 #endif
1261
1262         /* Worst case, we will use the NULL compression, but if we have other
1263          * options, we will now look for them.  We have i-1 compression
1264          * algorithms from the client, starting at q. */
1265         s->s3->tmp.new_compression=NULL;
1266 #ifndef OPENSSL_NO_COMP
1267         /* This only happens if we have a cache hit */
1268         if (s->session->compress_meth != 0)
1269                 {
1270                 int m, comp_id = s->session->compress_meth;
1271                 /* Perform sanity checks on resumed compression algorithm */
1272                 /* Can't disable compression */
1273                 if (!ssl_allow_compression(s))
1274                         {
1275                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_INCONSISTENT_COMPRESSION);
1276                         goto f_err;
1277                         }
1278                 /* Look for resumed compression method */
1279                 for (m = 0; m < sk_SSL_COMP_num(s->ctx->comp_methods); m++)
1280                         {
1281                         comp=sk_SSL_COMP_value(s->ctx->comp_methods,m);
1282                         if (comp_id == comp->id)
1283                                 {
1284                                 s->s3->tmp.new_compression=comp;
1285                                 break;
1286                                 }
1287                         }
1288                 if (s->s3->tmp.new_compression == NULL)
1289                         {
1290                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_INVALID_COMPRESSION_ALGORITHM);
1291                         goto f_err;
1292                         }
1293                 /* Look for resumed method in compression list */
1294                 for (m = 0; m < i; m++)
1295                         {
1296                         if (q[m] == comp_id)
1297                                 break;
1298                         }
1299                 if (m >= i)
1300                         {
1301                         al=SSL_AD_ILLEGAL_PARAMETER;
1302                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_REQUIRED_COMPRESSSION_ALGORITHM_MISSING);
1303                         goto f_err;
1304                         }
1305                 }
1306         else if (s->hit)
1307                 comp = NULL;
1308         else if (ssl_allow_compression(s) && s->ctx->comp_methods)
1309                 { /* See if we have a match */
1310                 int m,nn,o,v,done=0;
1311
1312                 nn=sk_SSL_COMP_num(s->ctx->comp_methods);
1313                 for (m=0; m<nn; m++)
1314                         {
1315                         comp=sk_SSL_COMP_value(s->ctx->comp_methods,m);
1316                         v=comp->id;
1317                         for (o=0; o<i; o++)
1318                                 {
1319                                 if (v == q[o])
1320                                         {
1321                                         done=1;
1322                                         break;
1323                                         }
1324                                 }
1325                         if (done) break;
1326                         }
1327                 if (done)
1328                         s->s3->tmp.new_compression=comp;
1329                 else
1330                         comp=NULL;
1331                 }
1332 #else
1333         /* If compression is disabled we'd better not try to resume a session
1334          * using compression.
1335          */
1336         if (s->session->compress_meth != 0)
1337                 {
1338                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_INCONSISTENT_COMPRESSION);
1339                 goto f_err;
1340                 }
1341 #endif
1342
1343         /* Given s->session->ciphers and SSL_get_ciphers, we must
1344          * pick a cipher */
1345
1346         if (!s->hit)
1347                 {
1348 #ifdef OPENSSL_NO_COMP
1349                 s->session->compress_meth=0;
1350 #else
1351                 s->session->compress_meth=(comp == NULL)?0:comp->id;
1352 #endif
1353                 if (s->session->ciphers != NULL)
1354                         sk_SSL_CIPHER_free(s->session->ciphers);
1355                 s->session->ciphers=ciphers;
1356                 if (ciphers == NULL)
1357                         {
1358                         al=SSL_AD_ILLEGAL_PARAMETER;
1359                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_NO_CIPHERS_PASSED);
1360                         goto f_err;
1361                         }
1362                 ciphers=NULL;
1363                 if (!tls1_set_server_sigalgs(s))
1364                         {
1365                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_CLIENTHELLO_TLSEXT);
1366                         goto err;
1367                         }
1368                 /* Let cert callback update server certificates if required */
1369                 retry_cert:             
1370                 if (s->cert->cert_cb)
1371                         {
1372                         int rv = s->cert->cert_cb(s, s->cert->cert_cb_arg);
1373                         if (rv == 0)
1374                                 {
1375                                 al=SSL_AD_INTERNAL_ERROR;
1376                                 SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_CERT_CB_ERROR);
1377                                 goto f_err;
1378                                 }
1379                         if (rv < 0)
1380                                 {
1381                                 s->rwstate=SSL_X509_LOOKUP;
1382                                 return -1;
1383                                 }
1384                         s->rwstate = SSL_NOTHING;
1385                         }
1386                 c=ssl3_choose_cipher(s,s->session->ciphers,
1387                                      SSL_get_ciphers(s));
1388
1389                 if (c == NULL)
1390                         {
1391                         al=SSL_AD_HANDSHAKE_FAILURE;
1392                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,SSL_R_NO_SHARED_CIPHER);
1393                         goto f_err;
1394                         }
1395                 s->s3->tmp.new_cipher=c;
1396                 /* check whether we should disable session resumption */
1397                 if (s->not_resumable_session_cb != NULL)
1398                         s->session->not_resumable=s->not_resumable_session_cb(s,
1399                                 ((c->algorithm_mkey & (SSL_kDHE | SSL_kECDHE)) != 0));
1400                 if (s->session->not_resumable)
1401                         /* do not send a session ticket */
1402                         s->tlsext_ticket_expected = 0;
1403                 }
1404         else
1405                 {
1406                 /* Session-id reuse */
1407 #ifdef REUSE_CIPHER_BUG
1408                 STACK_OF(SSL_CIPHER) *sk;
1409                 SSL_CIPHER *nc=NULL;
1410                 SSL_CIPHER *ec=NULL;
1411
1412                 if (s->options & SSL_OP_NETSCAPE_DEMO_CIPHER_CHANGE_BUG)
1413                         {
1414                         sk=s->session->ciphers;
1415                         for (i=0; i<sk_SSL_CIPHER_num(sk); i++)
1416                                 {
1417                                 c=sk_SSL_CIPHER_value(sk,i);
1418                                 if (c->algorithm_enc & SSL_eNULL)
1419                                         nc=c;
1420                                 if (SSL_C_IS_EXPORT(c))
1421                                         ec=c;
1422                                 }
1423                         if (nc != NULL)
1424                                 s->s3->tmp.new_cipher=nc;
1425                         else if (ec != NULL)
1426                                 s->s3->tmp.new_cipher=ec;
1427                         else
1428                                 s->s3->tmp.new_cipher=s->session->cipher;
1429                         }
1430                 else
1431 #endif
1432                 s->s3->tmp.new_cipher=s->session->cipher;
1433                 }
1434
1435         if (!SSL_USE_SIGALGS(s) || !(s->verify_mode & SSL_VERIFY_PEER))
1436                 {
1437                 if (!ssl3_digest_cached_records(s))
1438                         goto f_err;
1439                 }
1440         
1441         /*-
1442          * we now have the following setup. 
1443          * client_random
1444          * cipher_list          - our prefered list of ciphers
1445          * ciphers              - the clients prefered list of ciphers
1446          * compression          - basically ignored right now
1447          * ssl version is set   - sslv3
1448          * s->session           - The ssl session has been setup.
1449          * s->hit               - session reuse flag
1450          * s->s3->tmp.new_cipher- the new cipher to use.
1451          */
1452
1453         /* Handles TLS extensions that we couldn't check earlier */
1454         if (s->version >= SSL3_VERSION)
1455                 {
1456                 if (ssl_check_clienthello_tlsext_late(s) <= 0)
1457                         {
1458                         SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_CLIENTHELLO_TLSEXT);
1459                         goto err;
1460                         }
1461                 }
1462
1463         if (ret < 0) ret=-ret;
1464         if (0)
1465                 {
1466 f_err:
1467                 ssl3_send_alert(s,SSL3_AL_FATAL,al);
1468                 }
1469 err:
1470         if (ciphers != NULL) sk_SSL_CIPHER_free(ciphers);
1471         return ret < 0 ? -1 : ret;
1472         }
1473
1474 int ssl3_send_server_hello(SSL *s)
1475         {
1476         unsigned char *buf;
1477         unsigned char *p,*d;
1478         int i,sl;
1479         int al = 0;
1480         unsigned long l;
1481
1482         if (s->state == SSL3_ST_SW_SRVR_HELLO_A)
1483                 {
1484                 buf=(unsigned char *)s->init_buf->data;
1485 #ifdef OPENSSL_NO_TLSEXT
1486                 p=s->s3->server_random;
1487                 if (ssl_fill_hello_random(s, 1, p, SSL3_RANDOM_SIZE) <= 0)
1488                         return -1;
1489 #endif
1490                 /* Do the message type and length last */
1491                 d=p= ssl_handshake_start(s);
1492
1493                 *(p++)=s->version>>8;
1494                 *(p++)=s->version&0xff;
1495
1496                 /* Random stuff */
1497                 memcpy(p,s->s3->server_random,SSL3_RANDOM_SIZE);
1498                 p+=SSL3_RANDOM_SIZE;
1499
1500                 /*-
1501                  * There are several cases for the session ID to send
1502                  * back in the server hello:
1503                  * - For session reuse from the session cache,
1504                  *   we send back the old session ID.
1505                  * - If stateless session reuse (using a session ticket)
1506                  *   is successful, we send back the client's "session ID"
1507                  *   (which doesn't actually identify the session).
1508                  * - If it is a new session, we send back the new
1509                  *   session ID.
1510                  * - However, if we want the new session to be single-use,
1511                  *   we send back a 0-length session ID.
1512                  * s->hit is non-zero in either case of session reuse,
1513                  * so the following won't overwrite an ID that we're supposed
1514                  * to send back.
1515                  */
1516                 if (s->session->not_resumable ||
1517                         (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER)
1518                                 && !s->hit))
1519                         s->session->session_id_length=0;
1520
1521                 sl=s->session->session_id_length;
1522                 if (sl > (int)sizeof(s->session->session_id))
1523                         {
1524                         SSLerr(SSL_F_SSL3_SEND_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
1525                         return -1;
1526                         }
1527                 *(p++)=sl;
1528                 memcpy(p,s->session->session_id,sl);
1529                 p+=sl;
1530
1531                 /* put the cipher */
1532                 i=ssl3_put_cipher_by_char(s->s3->tmp.new_cipher,p);
1533                 p+=i;
1534
1535                 /* put the compression method */
1536 #ifdef OPENSSL_NO_COMP
1537                         *(p++)=0;
1538 #else
1539                 if (s->s3->tmp.new_compression == NULL)
1540                         *(p++)=0;
1541                 else
1542                         *(p++)=s->s3->tmp.new_compression->id;
1543 #endif
1544 #ifndef OPENSSL_NO_TLSEXT
1545                 if (ssl_prepare_serverhello_tlsext(s) <= 0)
1546                         {
1547                         SSLerr(SSL_F_SSL3_SEND_SERVER_HELLO,SSL_R_SERVERHELLO_TLSEXT);
1548                         return -1;
1549                         }
1550                 if ((p = ssl_add_serverhello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH, &al)) == NULL)
1551                         {
1552                         ssl3_send_alert(s, SSL3_AL_FATAL, al);
1553                         SSLerr(SSL_F_SSL3_SEND_SERVER_HELLO,ERR_R_INTERNAL_ERROR);
1554                         return -1;
1555                         }
1556 #endif
1557                 /* do the header */
1558                 l=(p-d);
1559                 ssl_set_handshake_header(s, SSL3_MT_SERVER_HELLO, l);
1560                 s->state=SSL3_ST_SW_SRVR_HELLO_B;
1561                 }
1562
1563         /* SSL3_ST_SW_SRVR_HELLO_B */
1564         return ssl_do_write(s);
1565         }
1566
1567 int ssl3_send_server_done(SSL *s)
1568         {
1569
1570         if (s->state == SSL3_ST_SW_SRVR_DONE_A)
1571                 {
1572                 ssl_set_handshake_header(s, SSL3_MT_SERVER_DONE, 0);
1573                 s->state = SSL3_ST_SW_SRVR_DONE_B;
1574                 }
1575
1576         /* SSL3_ST_SW_SRVR_DONE_B */
1577         return ssl_do_write(s);
1578         }
1579
1580 int ssl3_send_server_key_exchange(SSL *s)
1581         {
1582 #ifndef OPENSSL_NO_RSA
1583         unsigned char *q;
1584         int j,num;
1585         RSA *rsa;
1586         unsigned char md_buf[MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH];
1587         unsigned int u;
1588 #endif
1589 #ifndef OPENSSL_NO_DH
1590         DH *dh=NULL,*dhp;
1591 #endif
1592 #ifndef OPENSSL_NO_ECDH
1593         EC_KEY *ecdh=NULL, *ecdhp;
1594         unsigned char *encodedPoint = NULL;
1595         int encodedlen = 0;
1596         int curve_id = 0;
1597         BN_CTX *bn_ctx = NULL; 
1598 #endif
1599         EVP_PKEY *pkey;
1600         const EVP_MD *md = NULL;
1601         unsigned char *p,*d;
1602         int al,i;
1603         unsigned long type;
1604         int n;
1605         CERT *cert;
1606         BIGNUM *r[4];
1607         int nr[4],kn;
1608         BUF_MEM *buf;
1609         EVP_MD_CTX md_ctx;
1610
1611         EVP_MD_CTX_init(&md_ctx);
1612         if (s->state == SSL3_ST_SW_KEY_EXCH_A)
1613                 {
1614                 type=s->s3->tmp.new_cipher->algorithm_mkey;
1615                 cert=s->cert;
1616
1617                 buf=s->init_buf;
1618
1619                 r[0]=r[1]=r[2]=r[3]=NULL;
1620                 n=0;
1621 #ifndef OPENSSL_NO_RSA
1622                 if (type & SSL_kRSA)
1623                         {
1624                         rsa=cert->rsa_tmp;
1625                         if ((rsa == NULL) && (s->cert->rsa_tmp_cb != NULL))
1626                                 {
1627                                 rsa=s->cert->rsa_tmp_cb(s,
1628                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
1629                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
1630                                 if(rsa == NULL)
1631                                 {
1632                                         al=SSL_AD_HANDSHAKE_FAILURE;
1633                                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_ERROR_GENERATING_TMP_RSA_KEY);
1634                                         goto f_err;
1635                                 }
1636                                 RSA_up_ref(rsa);
1637                                 cert->rsa_tmp=rsa;
1638                                 }
1639                         if (rsa == NULL)
1640                                 {
1641                                 al=SSL_AD_HANDSHAKE_FAILURE;
1642                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_RSA_KEY);
1643                                 goto f_err;
1644                                 }
1645                         r[0]=rsa->n;
1646                         r[1]=rsa->e;
1647                         s->s3->tmp.use_rsa_tmp=1;
1648                         }
1649                 else
1650 #endif
1651 #ifndef OPENSSL_NO_DH
1652                         if (type & SSL_kDHE)
1653                         {
1654                         if (s->cert->dh_tmp_auto)
1655                                 {
1656                                 dhp = ssl_get_auto_dh(s);
1657                                 if (dhp == NULL)
1658                                         {
1659                                         al=SSL_AD_INTERNAL_ERROR;
1660                                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_INTERNAL_ERROR);
1661                                         goto f_err;
1662                                         }
1663                                 }
1664                         else
1665                                 dhp=cert->dh_tmp;
1666                         if ((dhp == NULL) && (s->cert->dh_tmp_cb != NULL))
1667                                 dhp=s->cert->dh_tmp_cb(s,
1668                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
1669                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
1670                         if (dhp == NULL)
1671                                 {
1672                                 al=SSL_AD_HANDSHAKE_FAILURE;
1673                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
1674                                 goto f_err;
1675                                 }
1676                         if (!ssl_security(s, SSL_SECOP_TMP_DH,
1677                                                 DH_security_bits(dhp), 0, dhp))
1678                                 {
1679                                 al=SSL_AD_HANDSHAKE_FAILURE;
1680                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_DH_KEY_TOO_SMALL);
1681                                 goto f_err;
1682                                 }
1683                         if (s->s3->tmp.dh != NULL)
1684                                 {
1685                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
1686                                 goto err;
1687                                 }
1688
1689                         if (s->cert->dh_tmp_auto)
1690                                 dh = dhp;
1691                         else if ((dh=DHparams_dup(dhp)) == NULL)
1692                                 {
1693                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
1694                                 goto err;
1695                                 }
1696
1697                         s->s3->tmp.dh=dh;
1698                         if ((dhp->pub_key == NULL ||
1699                              dhp->priv_key == NULL ||
1700                              (s->options & SSL_OP_SINGLE_DH_USE)))
1701                                 {
1702                                 if(!DH_generate_key(dh))
1703                                     {
1704                                     SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,
1705                                            ERR_R_DH_LIB);
1706                                     goto err;
1707                                     }
1708                                 }
1709                         else
1710                                 {
1711                                 dh->pub_key=BN_dup(dhp->pub_key);
1712                                 dh->priv_key=BN_dup(dhp->priv_key);
1713                                 if ((dh->pub_key == NULL) ||
1714                                         (dh->priv_key == NULL))
1715                                         {
1716                                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
1717                                         goto err;
1718                                         }
1719                                 }
1720                         r[0]=dh->p;
1721                         r[1]=dh->g;
1722                         r[2]=dh->pub_key;
1723                         }
1724                 else 
1725 #endif
1726 #ifndef OPENSSL_NO_ECDH
1727                         if (type & SSL_kECDHE)
1728                         {
1729                         const EC_GROUP *group;
1730
1731                         ecdhp=cert->ecdh_tmp;
1732                         if (s->cert->ecdh_tmp_auto)
1733                                 {
1734                                 /* Get NID of appropriate shared curve */
1735                                 int nid = tls1_shared_curve(s, -2);
1736                                 if (nid != NID_undef)
1737                                         ecdhp = EC_KEY_new_by_curve_name(nid);
1738                                 }
1739                         else if ((ecdhp == NULL) && s->cert->ecdh_tmp_cb)
1740                                 {
1741                                 ecdhp=s->cert->ecdh_tmp_cb(s,
1742                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
1743                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
1744                                 }
1745                         if (ecdhp == NULL)
1746                                 {
1747                                 al=SSL_AD_HANDSHAKE_FAILURE;
1748                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_ECDH_KEY);
1749                                 goto f_err;
1750                                 }
1751
1752                         if (s->s3->tmp.ecdh != NULL)
1753                                 {
1754                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
1755                                 goto err;
1756                                 }
1757
1758                         /* Duplicate the ECDH structure. */
1759                         if (ecdhp == NULL)
1760                                 {
1761                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
1762                                 goto err;
1763                                 }
1764                         if (s->cert->ecdh_tmp_auto)
1765                                 ecdh = ecdhp;
1766                         else if ((ecdh = EC_KEY_dup(ecdhp)) == NULL)
1767                                 {
1768                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
1769                                 goto err;
1770                                 }
1771
1772                         s->s3->tmp.ecdh=ecdh;
1773                         if ((EC_KEY_get0_public_key(ecdh) == NULL) ||
1774                             (EC_KEY_get0_private_key(ecdh) == NULL) ||
1775                             (s->options & SSL_OP_SINGLE_ECDH_USE))
1776                                 {
1777                                 if(!EC_KEY_generate_key(ecdh))
1778                                     {
1779                                     SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
1780                                     goto err;
1781                                     }
1782                                 }
1783
1784                         if (((group = EC_KEY_get0_group(ecdh)) == NULL) ||
1785                             (EC_KEY_get0_public_key(ecdh)  == NULL) ||
1786                             (EC_KEY_get0_private_key(ecdh) == NULL))
1787                                 {
1788                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
1789                                 goto err;
1790                                 }
1791
1792                         if (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher) &&
1793                             (EC_GROUP_get_degree(group) > 163)) 
1794                                 {
1795                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_ECGROUP_TOO_LARGE_FOR_CIPHER);
1796                                 goto err;
1797                                 }
1798
1799                         /* XXX: For now, we only support ephemeral ECDH
1800                          * keys over named (not generic) curves. For 
1801                          * supported named curves, curve_id is non-zero.
1802                          */
1803                         if ((curve_id = 
1804                             tls1_ec_nid2curve_id(EC_GROUP_get_curve_name(group)))
1805                             == 0)
1806                                 {
1807                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNSUPPORTED_ELLIPTIC_CURVE);
1808                                 goto err;
1809                                 }
1810
1811                         /* Encode the public key.
1812                          * First check the size of encoding and
1813                          * allocate memory accordingly.
1814                          */
1815                         encodedlen = EC_POINT_point2oct(group, 
1816                             EC_KEY_get0_public_key(ecdh),
1817                             POINT_CONVERSION_UNCOMPRESSED, 
1818                             NULL, 0, NULL);
1819
1820                         encodedPoint = (unsigned char *) 
1821                             OPENSSL_malloc(encodedlen*sizeof(unsigned char)); 
1822                         bn_ctx = BN_CTX_new();
1823                         if ((encodedPoint == NULL) || (bn_ctx == NULL))
1824                                 {
1825                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_MALLOC_FAILURE);
1826                                 goto err;
1827                                 }
1828
1829
1830                         encodedlen = EC_POINT_point2oct(group, 
1831                             EC_KEY_get0_public_key(ecdh), 
1832                             POINT_CONVERSION_UNCOMPRESSED, 
1833                             encodedPoint, encodedlen, bn_ctx);
1834
1835                         if (encodedlen == 0) 
1836                                 {
1837                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
1838                                 goto err;
1839                                 }
1840
1841                         BN_CTX_free(bn_ctx);  bn_ctx=NULL;
1842
1843                         /* XXX: For now, we only support named (not 
1844                          * generic) curves in ECDH ephemeral key exchanges.
1845                          * In this situation, we need four additional bytes
1846                          * to encode the entire ServerECDHParams
1847                          * structure. 
1848                          */
1849                         n = 4 + encodedlen;
1850
1851                         /* We'll generate the serverKeyExchange message
1852                          * explicitly so we can set these to NULLs
1853                          */
1854                         r[0]=NULL;
1855                         r[1]=NULL;
1856                         r[2]=NULL;
1857                         r[3]=NULL;
1858                         }
1859                 else 
1860 #endif /* !OPENSSL_NO_ECDH */
1861 #ifndef OPENSSL_NO_PSK
1862                         if (type & SSL_kPSK)
1863                                 {
1864                                 /* reserve size for record length and PSK identity hint*/
1865                                 n+=2+strlen(s->ctx->psk_identity_hint);
1866                                 }
1867                         else
1868 #endif /* !OPENSSL_NO_PSK */
1869 #ifndef OPENSSL_NO_SRP
1870                 if (type & SSL_kSRP)
1871                         {
1872                         if ((s->srp_ctx.N == NULL) ||
1873                                 (s->srp_ctx.g == NULL) ||
1874                                 (s->srp_ctx.s == NULL) ||
1875                                 (s->srp_ctx.B == NULL))
1876                                 {
1877                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_SRP_PARAM);
1878                                 goto err;
1879                                 }
1880                         r[0]=s->srp_ctx.N;
1881                         r[1]=s->srp_ctx.g;
1882                         r[2]=s->srp_ctx.s;
1883                         r[3]=s->srp_ctx.B;
1884                         }
1885                 else 
1886 #endif
1887                         {
1888                         al=SSL_AD_HANDSHAKE_FAILURE;
1889                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE);
1890                         goto f_err;
1891                         }
1892                 for (i=0; i < 4 && r[i] != NULL; i++)
1893                         {
1894                         nr[i]=BN_num_bytes(r[i]);
1895 #ifndef OPENSSL_NO_SRP
1896                         if ((i == 2) && (type & SSL_kSRP))
1897                                 n+=1+nr[i];
1898                         else
1899 #endif
1900                         n+=2+nr[i];
1901                         }
1902
1903                 if (!(s->s3->tmp.new_cipher->algorithm_auth & (SSL_aNULL|SSL_aSRP))
1904                         && !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
1905                         {
1906                         if ((pkey=ssl_get_sign_pkey(s,s->s3->tmp.new_cipher,&md))
1907                                 == NULL)
1908                                 {
1909                                 al=SSL_AD_DECODE_ERROR;
1910                                 goto f_err;
1911                                 }
1912                         kn=EVP_PKEY_size(pkey);
1913                         }
1914                 else
1915                         {
1916                         pkey=NULL;
1917                         kn=0;
1918                         }
1919
1920                 if (!BUF_MEM_grow_clean(buf,n+SSL_HM_HEADER_LENGTH(s)+kn))
1921                         {
1922                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_BUF);
1923                         goto err;
1924                         }
1925                 d = p = ssl_handshake_start(s);
1926
1927                 for (i=0; i < 4 && r[i] != NULL; i++)
1928                         {
1929 #ifndef OPENSSL_NO_SRP
1930                         if ((i == 2) && (type & SSL_kSRP))
1931                                 {
1932                                 *p = nr[i];
1933                                 p++;
1934                                 }
1935                         else
1936 #endif
1937                         s2n(nr[i],p);
1938                         BN_bn2bin(r[i],p);
1939                         p+=nr[i];
1940                         }
1941
1942 #ifndef OPENSSL_NO_ECDH
1943                 if (type & SSL_kECDHE) 
1944                         {
1945                         /* XXX: For now, we only support named (not generic) curves.
1946                          * In this situation, the serverKeyExchange message has:
1947                          * [1 byte CurveType], [2 byte CurveName]
1948                          * [1 byte length of encoded point], followed by
1949                          * the actual encoded point itself
1950                          */
1951                         *p = NAMED_CURVE_TYPE;
1952                         p += 1;
1953                         *p = 0;
1954                         p += 1;
1955                         *p = curve_id;
1956                         p += 1;
1957                         *p = encodedlen;
1958                         p += 1;
1959                         memcpy((unsigned char*)p, 
1960                             (unsigned char *)encodedPoint, 
1961                             encodedlen);
1962                         OPENSSL_free(encodedPoint);
1963                         encodedPoint = NULL;
1964                         p += encodedlen;
1965                         }
1966 #endif
1967
1968 #ifndef OPENSSL_NO_PSK
1969                 if (type & SSL_kPSK)
1970                         {
1971                         /* copy PSK identity hint */
1972                         s2n(strlen(s->ctx->psk_identity_hint), p); 
1973                         strncpy((char *)p, s->ctx->psk_identity_hint, strlen(s->ctx->psk_identity_hint));
1974                         p+=strlen(s->ctx->psk_identity_hint);
1975                         }
1976 #endif
1977
1978                 /* not anonymous */
1979                 if (pkey != NULL)
1980                         {
1981                         /* n is the length of the params, they start at &(d[4])
1982                          * and p points to the space at the end. */
1983 #ifndef OPENSSL_NO_RSA
1984                         if (pkey->type == EVP_PKEY_RSA && !SSL_USE_SIGALGS(s))
1985                                 {
1986                                 q=md_buf;
1987                                 j=0;
1988                                 for (num=2; num > 0; num--)
1989                                         {
1990                                         EVP_MD_CTX_set_flags(&md_ctx,
1991                                                 EVP_MD_CTX_FLAG_NON_FIPS_ALLOW);
1992                                         EVP_DigestInit_ex(&md_ctx,(num == 2)
1993                                                 ?s->ctx->md5:s->ctx->sha1, NULL);
1994                                         EVP_DigestUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
1995                                         EVP_DigestUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
1996                                         EVP_DigestUpdate(&md_ctx,d,n);
1997                                         EVP_DigestFinal_ex(&md_ctx,q,
1998                                                 (unsigned int *)&i);
1999                                         q+=i;
2000                                         j+=i;
2001                                         }
2002                                 if (RSA_sign(NID_md5_sha1, md_buf, j,
2003                                         &(p[2]), &u, pkey->pkey.rsa) <= 0)
2004                                         {
2005                                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_RSA);
2006                                         goto err;
2007                                         }
2008                                 s2n(u,p);
2009                                 n+=u+2;
2010                                 }
2011                         else
2012 #endif
2013                         if (md)
2014                                 {
2015                                 /* send signature algorithm */
2016                                 if (SSL_USE_SIGALGS(s))
2017                                         {
2018                                         if (!tls12_get_sigandhash(p, pkey, md))
2019                                                 {
2020                                                 /* Should never happen */
2021                                                 al=SSL_AD_INTERNAL_ERROR;
2022                                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_INTERNAL_ERROR);
2023                                                 goto f_err;
2024                                                 }
2025                                         p+=2;
2026                                         }
2027 #ifdef SSL_DEBUG
2028                                 fprintf(stderr, "Using hash %s\n",
2029                                                         EVP_MD_name(md));
2030 #endif
2031                                 EVP_SignInit_ex(&md_ctx, md, NULL);
2032                                 EVP_SignUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
2033                                 EVP_SignUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
2034                                 EVP_SignUpdate(&md_ctx,d,n);
2035                                 if (!EVP_SignFinal(&md_ctx,&(p[2]),
2036                                         (unsigned int *)&i,pkey))
2037                                         {
2038                                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_EVP);
2039                                         goto err;
2040                                         }
2041                                 s2n(i,p);
2042                                 n+=i+2;
2043                                 if (SSL_USE_SIGALGS(s))
2044                                         n+= 2;
2045                                 }
2046                         else
2047                                 {
2048                                 /* Is this error check actually needed? */
2049                                 al=SSL_AD_HANDSHAKE_FAILURE;
2050                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_PKEY_TYPE);
2051                                 goto f_err;
2052                                 }
2053                         }
2054
2055                 ssl_set_handshake_header(s, SSL3_MT_SERVER_KEY_EXCHANGE, n);
2056                 }
2057
2058         s->state = SSL3_ST_SW_KEY_EXCH_B;
2059         EVP_MD_CTX_cleanup(&md_ctx);
2060         return ssl_do_write(s);
2061 f_err:
2062         ssl3_send_alert(s,SSL3_AL_FATAL,al);
2063 err:
2064 #ifndef OPENSSL_NO_ECDH
2065         if (encodedPoint != NULL) OPENSSL_free(encodedPoint);
2066         BN_CTX_free(bn_ctx);
2067 #endif
2068         EVP_MD_CTX_cleanup(&md_ctx);
2069         return(-1);
2070         }
2071
2072 int ssl3_send_certificate_request(SSL *s)
2073         {
2074         unsigned char *p,*d;
2075         int i,j,nl,off,n;
2076         STACK_OF(X509_NAME) *sk=NULL;
2077         X509_NAME *name;
2078         BUF_MEM *buf;
2079
2080         if (s->state == SSL3_ST_SW_CERT_REQ_A)
2081                 {
2082                 buf=s->init_buf;
2083
2084                 d=p=ssl_handshake_start(s);
2085
2086                 /* get the list of acceptable cert types */
2087                 p++;
2088                 n=ssl3_get_req_cert_type(s,p);
2089                 d[0]=n;
2090                 p+=n;
2091                 n++;
2092
2093                 if (SSL_USE_SIGALGS(s))
2094                         {
2095                         const unsigned char *psigs;
2096                         unsigned char *etmp = p;
2097                         nl = tls12_get_psigalgs(s, &psigs);
2098                         /* Skip over length for now */
2099                         p += 2;
2100                         nl = tls12_copy_sigalgs(s, p, psigs, nl);
2101                         /* Now fill in length */
2102                         s2n(nl, etmp);
2103                         p += nl;
2104                         n += nl + 2;
2105                         }
2106
2107                 off=n;
2108                 p+=2;
2109                 n+=2;
2110
2111                 sk=SSL_get_client_CA_list(s);
2112                 nl=0;
2113                 if (sk != NULL)
2114                         {
2115                         for (i=0; i<sk_X509_NAME_num(sk); i++)
2116                                 {
2117                                 name=sk_X509_NAME_value(sk,i);
2118                                 j=i2d_X509_NAME(name,NULL);
2119                                 if (!BUF_MEM_grow_clean(buf,SSL_HM_HEADER_LENGTH(s)+n+j+2))
2120                                         {
2121                                         SSLerr(SSL_F_SSL3_SEND_CERTIFICATE_REQUEST,ERR_R_BUF_LIB);
2122                                         goto err;
2123                                         }
2124                                 p = ssl_handshake_start(s) + n;
2125                                 if (!(s->options & SSL_OP_NETSCAPE_CA_DN_BUG))
2126                                         {
2127                                         s2n(j,p);
2128                                         i2d_X509_NAME(name,&p);
2129                                         n+=2+j;
2130                                         nl+=2+j;
2131                                         }
2132                                 else
2133                                         {
2134                                         d=p;
2135                                         i2d_X509_NAME(name,&p);
2136                                         j-=2; s2n(j,d); j+=2;
2137                                         n+=j;
2138                                         nl+=j;
2139                                         }
2140                                 }
2141                         }
2142                 /* else no CA names */
2143                 p = ssl_handshake_start(s) + off;
2144                 s2n(nl,p);
2145
2146                 ssl_set_handshake_header(s, SSL3_MT_CERTIFICATE_REQUEST, n);
2147
2148 #ifdef NETSCAPE_HANG_BUG
2149                 if (!SSL_IS_DTLS(s))
2150                         {
2151                         if (!BUF_MEM_grow_clean(buf, s->init_num + 4))
2152                                 {
2153                                 SSLerr(SSL_F_SSL3_SEND_CERTIFICATE_REQUEST,ERR_R_BUF_LIB);
2154                                 goto err;
2155                                 }
2156                         p=(unsigned char *)s->init_buf->data + s->init_num;
2157                         /* do the header */
2158                         *(p++)=SSL3_MT_SERVER_DONE;
2159                         *(p++)=0;
2160                         *(p++)=0;
2161                         *(p++)=0;
2162                         s->init_num += 4;
2163                         }
2164 #endif
2165
2166                 s->state = SSL3_ST_SW_CERT_REQ_B;
2167                 }
2168
2169         /* SSL3_ST_SW_CERT_REQ_B */
2170         return ssl_do_write(s);
2171 err:
2172         return(-1);
2173         }
2174
2175 int ssl3_get_client_key_exchange(SSL *s)
2176         {
2177         int i,al,ok;
2178         long n;
2179         unsigned long alg_k;
2180         unsigned char *p;
2181 #ifndef OPENSSL_NO_RSA
2182         RSA *rsa=NULL;
2183         EVP_PKEY *pkey=NULL;
2184 #endif
2185 #ifndef OPENSSL_NO_DH
2186         BIGNUM *pub=NULL;
2187         DH *dh_srvr, *dh_clnt = NULL;
2188 #endif
2189 #ifndef OPENSSL_NO_KRB5
2190         KSSL_ERR kssl_err;
2191 #endif /* OPENSSL_NO_KRB5 */
2192
2193 #ifndef OPENSSL_NO_ECDH
2194         EC_KEY *srvr_ecdh = NULL;
2195         EVP_PKEY *clnt_pub_pkey = NULL;
2196         EC_POINT *clnt_ecpoint = NULL;
2197         BN_CTX *bn_ctx = NULL; 
2198 #endif
2199
2200         n=s->method->ssl_get_message(s,
2201                 SSL3_ST_SR_KEY_EXCH_A,
2202                 SSL3_ST_SR_KEY_EXCH_B,
2203                 SSL3_MT_CLIENT_KEY_EXCHANGE,
2204                 2048,
2205                 &ok);
2206
2207         if (!ok) return((int)n);
2208         p=(unsigned char *)s->init_msg;
2209
2210         alg_k=s->s3->tmp.new_cipher->algorithm_mkey;
2211
2212 #ifndef OPENSSL_NO_RSA
2213         if (alg_k & SSL_kRSA)
2214                 {
2215                 unsigned char rand_premaster_secret[SSL_MAX_MASTER_KEY_LENGTH];
2216                 int decrypt_len;
2217                 unsigned char decrypt_good, version_good;
2218                 size_t j;
2219
2220                 /* FIX THIS UP EAY EAY EAY EAY */
2221                 if (s->s3->tmp.use_rsa_tmp)
2222                         {
2223                         if ((s->cert != NULL) && (s->cert->rsa_tmp != NULL))
2224                                 rsa=s->cert->rsa_tmp;
2225                         /* Don't do a callback because rsa_tmp should
2226                          * be sent already */
2227                         if (rsa == NULL)
2228                                 {
2229                                 al=SSL_AD_HANDSHAKE_FAILURE;
2230                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_TMP_RSA_PKEY);
2231                                 goto f_err;
2232
2233                                 }
2234                         }
2235                 else
2236                         {
2237                         pkey=s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey;
2238                         if (    (pkey == NULL) ||
2239                                 (pkey->type != EVP_PKEY_RSA) ||
2240                                 (pkey->pkey.rsa == NULL))
2241                                 {
2242                                 al=SSL_AD_HANDSHAKE_FAILURE;
2243                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_RSA_CERTIFICATE);
2244                                 goto f_err;
2245                                 }
2246                         rsa=pkey->pkey.rsa;
2247                         }
2248
2249                 /* TLS and [incidentally] DTLS{0xFEFF} */
2250                 if (s->version > SSL3_VERSION && s->version != DTLS1_BAD_VER)
2251                         {
2252                         n2s(p,i);
2253                         if (n != i+2)
2254                                 {
2255                                 if (!(s->options & SSL_OP_TLS_D5_BUG))
2256                                         {
2257                                         al = SSL_AD_DECODE_ERROR;
2258                                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_TLS_RSA_ENCRYPTED_VALUE_LENGTH_IS_WRONG);
2259                                         goto f_err;
2260                                         }
2261                                 else
2262                                         p-=2;
2263                                 }
2264                         else
2265                                 n=i;
2266                         }
2267
2268                 /*
2269                  * Reject overly short RSA ciphertext because we want to be sure
2270                  * that the buffer size makes it safe to iterate over the entire
2271                  * size of a premaster secret (SSL_MAX_MASTER_KEY_LENGTH). The
2272                  * actual expected size is larger due to RSA padding, but the
2273                  * bound is sufficient to be safe.
2274                  */
2275                 if (n < SSL_MAX_MASTER_KEY_LENGTH)
2276                         {
2277                         al = SSL_AD_DECRYPT_ERROR;
2278                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE, SSL_R_TLS_RSA_ENCRYPTED_VALUE_LENGTH_IS_WRONG);
2279                         goto f_err;
2280                         }
2281
2282                 /* We must not leak whether a decryption failure occurs because
2283                  * of Bleichenbacher's attack on PKCS #1 v1.5 RSA padding (see
2284                  * RFC 2246, section 7.4.7.1). The code follows that advice of
2285                  * the TLS RFC and generates a random premaster secret for the
2286                  * case that the decrypt fails. See
2287                  * https://tools.ietf.org/html/rfc5246#section-7.4.7.1 */
2288
2289                 /* should be RAND_bytes, but we cannot work around a failure. */
2290                 if (RAND_pseudo_bytes(rand_premaster_secret,
2291                                       sizeof(rand_premaster_secret)) <= 0)
2292                         goto err;
2293                 decrypt_len = RSA_private_decrypt((int)n,p,p,rsa,RSA_PKCS1_PADDING);
2294                 ERR_clear_error();
2295
2296                 /* decrypt_len should be SSL_MAX_MASTER_KEY_LENGTH.
2297                  * decrypt_good will be 0xff if so and zero otherwise. */
2298                 decrypt_good = constant_time_eq_int_8(decrypt_len, SSL_MAX_MASTER_KEY_LENGTH);
2299
2300                 /* If the version in the decrypted pre-master secret is correct
2301                  * then version_good will be 0xff, otherwise it'll be zero.
2302                  * The Klima-Pokorny-Rosa extension of Bleichenbacher's attack
2303                  * (http://eprint.iacr.org/2003/052/) exploits the version
2304                  * number check as a "bad version oracle". Thus version checks
2305                  * are done in constant time and are treated like any other
2306                  * decryption error. */
2307                 version_good = constant_time_eq_8(p[0], (unsigned)(s->client_version>>8));
2308                 version_good &= constant_time_eq_8(p[1], (unsigned)(s->client_version&0xff));
2309
2310                 /* The premaster secret must contain the same version number as
2311                  * the ClientHello to detect version rollback attacks
2312                  * (strangely, the protocol does not offer such protection for
2313                  * DH ciphersuites). However, buggy clients exist that send the
2314                  * negotiated protocol version instead if the server does not
2315                  * support the requested protocol version. If
2316                  * SSL_OP_TLS_ROLLBACK_BUG is set, tolerate such clients. */
2317                 if (s->options & SSL_OP_TLS_ROLLBACK_BUG)
2318                         {
2319                         unsigned char workaround_good;
2320                         workaround_good = constant_time_eq_8(p[0], (unsigned)(s->version>>8));
2321                         workaround_good &= constant_time_eq_8(p[1], (unsigned)(s->version&0xff));
2322                         version_good |= workaround_good;
2323                         }
2324
2325                 /* Both decryption and version must be good for decrypt_good
2326                  * to remain non-zero (0xff). */
2327                 decrypt_good &= version_good;
2328
2329                 /*
2330                  * Now copy rand_premaster_secret over from p using
2331                  * decrypt_good_mask. If decryption failed, then p does not
2332                  * contain valid plaintext, however, a check above guarantees
2333                  * it is still sufficiently large to read from.
2334                  */
2335                 for (j = 0; j < sizeof(rand_premaster_secret); j++)
2336                         {
2337                         p[j] = constant_time_select_8(decrypt_good, p[j],
2338                                                       rand_premaster_secret[j]);
2339                         }
2340
2341                 s->session->master_key_length=
2342                         s->method->ssl3_enc->generate_master_secret(s,
2343                                 s->session->master_key,
2344                                 p,sizeof(rand_premaster_secret));
2345                 OPENSSL_cleanse(p,sizeof(rand_premaster_secret));
2346                 }
2347         else
2348 #endif
2349 #ifndef OPENSSL_NO_DH
2350                 if (alg_k & (SSL_kDHE|SSL_kDHr|SSL_kDHd))
2351                 {
2352                 int idx = -1;
2353                 EVP_PKEY *skey = NULL;
2354                 if (n)
2355                         n2s(p,i);
2356                 else
2357                         i = 0;
2358                 if (n && n != i+2)
2359                         {
2360                         if (!(s->options & SSL_OP_SSLEAY_080_CLIENT_DH_BUG))
2361                                 {
2362                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_DH_PUBLIC_VALUE_LENGTH_IS_WRONG);
2363                                 goto err;
2364                                 }
2365                         else
2366                                 {
2367                                 p-=2;
2368                                 i=(int)n;
2369                                 }
2370                         }
2371                 if (alg_k & SSL_kDHr)
2372                         idx = SSL_PKEY_DH_RSA;
2373                 else if (alg_k & SSL_kDHd)
2374                         idx = SSL_PKEY_DH_DSA;
2375                 if (idx >= 0)
2376                         {
2377                         skey = s->cert->pkeys[idx].privatekey;
2378                         if ((skey == NULL) ||
2379                                 (skey->type != EVP_PKEY_DH) ||
2380                                 (skey->pkey.dh == NULL))
2381                                 {
2382                                 al=SSL_AD_HANDSHAKE_FAILURE;
2383                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_RSA_CERTIFICATE);
2384                                 goto f_err;
2385                                 }
2386                         dh_srvr = skey->pkey.dh;
2387                         }
2388                 else if (s->s3->tmp.dh == NULL)
2389                         {
2390                         al=SSL_AD_HANDSHAKE_FAILURE;
2391                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
2392                         goto f_err;
2393                         }
2394                 else
2395                         dh_srvr=s->s3->tmp.dh;
2396
2397                 if (n == 0L)
2398                         {
2399                         /* Get pubkey from cert */
2400                         EVP_PKEY *clkey=X509_get_pubkey(s->session->peer);
2401                         if (clkey)
2402                                 {
2403                                 if (EVP_PKEY_cmp_parameters(clkey, skey) == 1)
2404                                         dh_clnt = EVP_PKEY_get1_DH(clkey);
2405                                 }
2406                         if (dh_clnt == NULL)
2407                                 {
2408                                 al=SSL_AD_HANDSHAKE_FAILURE;
2409                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
2410                                 goto f_err;
2411                                 }
2412                         EVP_PKEY_free(clkey);
2413                         pub = dh_clnt->pub_key;
2414                         }
2415                 else
2416                         pub=BN_bin2bn(p,i,NULL);
2417                 if (pub == NULL)
2418                         {
2419                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_BN_LIB);
2420                         goto err;
2421                         }
2422
2423                 i=DH_compute_key(p,pub,dh_srvr);
2424
2425                 if (i <= 0)
2426                         {
2427                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,ERR_R_DH_LIB);
2428                         BN_clear_free(pub);
2429                         goto err;
2430                         }
2431
2432                 DH_free(s->s3->tmp.dh);
2433                 s->s3->tmp.dh=NULL;
2434                 if (dh_clnt)
2435                         DH_free(dh_clnt);
2436                 else
2437                         BN_clear_free(pub);
2438                 pub=NULL;
2439                 s->session->master_key_length=
2440                         s->method->ssl3_enc->generate_master_secret(s,
2441                                 s->session->master_key,p,i);
2442                 OPENSSL_cleanse(p,i);
2443                 if (dh_clnt)
2444                         return 2;
2445                 }
2446         else
2447 #endif
2448 #ifndef OPENSSL_NO_KRB5
2449         if (alg_k & SSL_kKRB5)
2450                 {
2451                 krb5_error_code         krb5rc;
2452                 krb5_data               enc_ticket;
2453                 krb5_data               authenticator;
2454                 krb5_data               enc_pms;
2455                 KSSL_CTX                *kssl_ctx = s->kssl_ctx;
2456                 EVP_CIPHER_CTX          ciph_ctx;
2457                 const EVP_CIPHER        *enc = NULL;
2458                 unsigned char           iv[EVP_MAX_IV_LENGTH];
2459                 unsigned char           pms[SSL_MAX_MASTER_KEY_LENGTH
2460                                                + EVP_MAX_BLOCK_LENGTH];
2461                 int                  padl, outl;
2462                 krb5_timestamp          authtime = 0;
2463                 krb5_ticket_times       ttimes;
2464
2465                 EVP_CIPHER_CTX_init(&ciph_ctx);
2466
2467                 if (!kssl_ctx)  kssl_ctx = kssl_ctx_new();
2468
2469                 n2s(p,i);
2470                 enc_ticket.length = i;
2471
2472                 if (n < (long)(enc_ticket.length + 6))
2473                         {
2474                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2475                                 SSL_R_DATA_LENGTH_TOO_LONG);
2476                         goto err;
2477                         }
2478
2479                 enc_ticket.data = (char *)p;
2480                 p+=enc_ticket.length;
2481
2482                 n2s(p,i);
2483                 authenticator.length = i;
2484
2485                 if (n < (long)(enc_ticket.length + authenticator.length + 6))
2486                         {
2487                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2488                                 SSL_R_DATA_LENGTH_TOO_LONG);
2489                         goto err;
2490                         }
2491
2492                 authenticator.data = (char *)p;
2493                 p+=authenticator.length;
2494
2495                 n2s(p,i);
2496                 enc_pms.length = i;
2497                 enc_pms.data = (char *)p;
2498                 p+=enc_pms.length;
2499
2500                 /* Note that the length is checked again below,
2501                 ** after decryption
2502                 */
2503                 if(enc_pms.length > sizeof pms)
2504                         {
2505                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2506                                SSL_R_DATA_LENGTH_TOO_LONG);
2507                         goto err;
2508                         }
2509
2510                 if (n != (long)(enc_ticket.length + authenticator.length +
2511                                                 enc_pms.length + 6))
2512                         {
2513                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2514                                 SSL_R_DATA_LENGTH_TOO_LONG);
2515                         goto err;
2516                         }
2517
2518                 if ((krb5rc = kssl_sget_tkt(kssl_ctx, &enc_ticket, &ttimes,
2519                                         &kssl_err)) != 0)
2520                         {
2521 #ifdef KSSL_DEBUG
2522                         fprintf(stderr,"kssl_sget_tkt rtn %d [%d]\n",
2523                                 krb5rc, kssl_err.reason);
2524                         if (kssl_err.text)
2525                                 fprintf(stderr,"kssl_err text= %s\n", kssl_err.text);
2526 #endif  /* KSSL_DEBUG */
2527                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2528                                 kssl_err.reason);
2529                         goto err;
2530                         }
2531
2532                 /*  Note: no authenticator is not considered an error,
2533                 **  but will return authtime == 0.
2534                 */
2535                 if ((krb5rc = kssl_check_authent(kssl_ctx, &authenticator,
2536                                         &authtime, &kssl_err)) != 0)
2537                         {
2538 #ifdef KSSL_DEBUG
2539                         fprintf(stderr,"kssl_check_authent rtn %d [%d]\n",
2540                                 krb5rc, kssl_err.reason);
2541                         if (kssl_err.text)
2542                                 fprintf(stderr,"kssl_err text= %s\n", kssl_err.text);
2543 #endif  /* KSSL_DEBUG */
2544                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2545                                 kssl_err.reason);
2546                         goto err;
2547                         }
2548
2549                 if ((krb5rc = kssl_validate_times(authtime, &ttimes)) != 0)
2550                         {
2551                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE, krb5rc);
2552                         goto err;
2553                         }
2554
2555 #ifdef KSSL_DEBUG
2556                 kssl_ctx_show(kssl_ctx);
2557 #endif  /* KSSL_DEBUG */
2558
2559                 enc = kssl_map_enc(kssl_ctx->enctype);
2560                 if (enc == NULL)
2561                     goto err;
2562
2563                 memset(iv, 0, sizeof iv);       /* per RFC 1510 */
2564
2565                 if (!EVP_DecryptInit_ex(&ciph_ctx,enc,NULL,kssl_ctx->key,iv))
2566                         {
2567                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2568                                 SSL_R_DECRYPTION_FAILED);
2569                         goto err;
2570                         }
2571                 if (!EVP_DecryptUpdate(&ciph_ctx, pms,&outl,
2572                                         (unsigned char *)enc_pms.data, enc_pms.length))
2573                         {
2574                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2575                                 SSL_R_DECRYPTION_FAILED);
2576                         goto err;
2577                         }
2578                 if (outl > SSL_MAX_MASTER_KEY_LENGTH)
2579                         {
2580                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2581                                 SSL_R_DATA_LENGTH_TOO_LONG);
2582                         goto err;
2583                         }
2584                 if (!EVP_DecryptFinal_ex(&ciph_ctx,&(pms[outl]),&padl))
2585                         {
2586                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2587                                 SSL_R_DECRYPTION_FAILED);
2588                         goto err;
2589                         }
2590                 outl += padl;
2591                 if (outl > SSL_MAX_MASTER_KEY_LENGTH)
2592                         {
2593                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2594                                 SSL_R_DATA_LENGTH_TOO_LONG);
2595                         goto err;
2596                         }
2597                 if (!((pms[0] == (s->client_version>>8)) && (pms[1] == (s->client_version & 0xff))))
2598                     {
2599                     /* The premaster secret must contain the same version number as the
2600                      * ClientHello to detect version rollback attacks (strangely, the
2601                      * protocol does not offer such protection for DH ciphersuites).
2602                      * However, buggy clients exist that send random bytes instead of
2603                      * the protocol version.
2604                      * If SSL_OP_TLS_ROLLBACK_BUG is set, tolerate such clients. 
2605                      * (Perhaps we should have a separate BUG value for the Kerberos cipher)
2606                      */
2607                     if (!(s->options & SSL_OP_TLS_ROLLBACK_BUG))
2608                         {
2609                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2610                                SSL_AD_DECODE_ERROR);
2611                         goto err;
2612                         }
2613                     }
2614
2615                 EVP_CIPHER_CTX_cleanup(&ciph_ctx);
2616
2617                 s->session->master_key_length=
2618                         s->method->ssl3_enc->generate_master_secret(s,
2619                                 s->session->master_key, pms, outl);
2620
2621                 if (kssl_ctx->client_princ)
2622                         {
2623                         size_t len = strlen(kssl_ctx->client_princ);
2624                         if ( len < SSL_MAX_KRB5_PRINCIPAL_LENGTH ) 
2625                                 {
2626                                 s->session->krb5_client_princ_len = len;
2627                                 memcpy(s->session->krb5_client_princ,kssl_ctx->client_princ,len);
2628                                 }
2629                         }
2630
2631
2632                 /*- Was doing kssl_ctx_free() here,
2633                  *  but it caused problems for apache.
2634                  *  kssl_ctx = kssl_ctx_free(kssl_ctx);
2635                  *  if (s->kssl_ctx)  s->kssl_ctx = NULL;
2636                  */
2637                 }
2638         else
2639 #endif  /* OPENSSL_NO_KRB5 */
2640
2641 #ifndef OPENSSL_NO_ECDH
2642                 if (alg_k & (SSL_kECDHE|SSL_kECDHr|SSL_kECDHe))
2643                 {
2644                 int ret = 1;
2645                 int field_size = 0;
2646                 const EC_KEY   *tkey;
2647                 const EC_GROUP *group;
2648                 const BIGNUM *priv_key;
2649
2650                 /* initialize structures for server's ECDH key pair */
2651                 if ((srvr_ecdh = EC_KEY_new()) == NULL) 
2652                         {
2653                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2654                             ERR_R_MALLOC_FAILURE);
2655                         goto err;
2656                         }
2657
2658                 /* Let's get server private key and group information */
2659                 if (alg_k & (SSL_kECDHr|SSL_kECDHe))
2660                         { 
2661                         /* use the certificate */
2662                         tkey = s->cert->pkeys[SSL_PKEY_ECC].privatekey->pkey.ec;
2663                         }
2664                 else
2665                         {
2666                         /* use the ephermeral values we saved when
2667                          * generating the ServerKeyExchange msg.
2668                          */
2669                         tkey = s->s3->tmp.ecdh;
2670                         }
2671
2672                 group    = EC_KEY_get0_group(tkey);
2673                 priv_key = EC_KEY_get0_private_key(tkey);
2674
2675                 if (!EC_KEY_set_group(srvr_ecdh, group) ||
2676                     !EC_KEY_set_private_key(srvr_ecdh, priv_key))
2677                         {
2678                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2679                                ERR_R_EC_LIB);
2680                         goto err;
2681                         }
2682
2683                 /* Let's get client's public key */
2684                 if ((clnt_ecpoint = EC_POINT_new(group)) == NULL)
2685                         {
2686                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2687                             ERR_R_MALLOC_FAILURE);
2688                         goto err;
2689                         }
2690
2691                 if (n == 0L) 
2692                         {
2693                         /* Client Publickey was in Client Certificate */
2694
2695                          if (alg_k & SSL_kECDHE)
2696                                  {
2697                                  al=SSL_AD_HANDSHAKE_FAILURE;
2698                                  SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_TMP_ECDH_KEY);
2699                                  goto f_err;
2700                                  }
2701                         if (((clnt_pub_pkey=X509_get_pubkey(s->session->peer))
2702                             == NULL) || 
2703                             (clnt_pub_pkey->type != EVP_PKEY_EC))
2704                                 {
2705                                 /* XXX: For now, we do not support client
2706                                  * authentication using ECDH certificates
2707                                  * so this branch (n == 0L) of the code is
2708                                  * never executed. When that support is
2709                                  * added, we ought to ensure the key 
2710                                  * received in the certificate is 
2711                                  * authorized for key agreement.
2712                                  * ECDH_compute_key implicitly checks that
2713                                  * the two ECDH shares are for the same
2714                                  * group.
2715                                  */
2716                                 al=SSL_AD_HANDSHAKE_FAILURE;
2717                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2718                                     SSL_R_UNABLE_TO_DECODE_ECDH_CERTS);
2719                                 goto f_err;
2720                                 }
2721
2722                         if (EC_POINT_copy(clnt_ecpoint,
2723                             EC_KEY_get0_public_key(clnt_pub_pkey->pkey.ec)) == 0)
2724                                 {
2725                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2726                                         ERR_R_EC_LIB);
2727                                 goto err;
2728                                 }
2729                         ret = 2; /* Skip certificate verify processing */
2730                         }
2731                 else
2732                         {
2733                         /* Get client's public key from encoded point
2734                          * in the ClientKeyExchange message.
2735                          */
2736                         if ((bn_ctx = BN_CTX_new()) == NULL)
2737                                 {
2738                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2739                                     ERR_R_MALLOC_FAILURE);
2740                                 goto err;
2741                                 }
2742
2743                         /* Get encoded point length */
2744                         i = *p; 
2745                         p += 1;
2746                         if (n != 1 + i)
2747                                 {
2748                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2749                                     ERR_R_EC_LIB);
2750                                 goto err;
2751                                 }
2752                         if (EC_POINT_oct2point(group, 
2753                             clnt_ecpoint, p, i, bn_ctx) == 0)
2754                                 {
2755                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2756                                     ERR_R_EC_LIB);
2757                                 goto err;
2758                                 }
2759                         /* p is pointing to somewhere in the buffer
2760                          * currently, so set it to the start 
2761                          */ 
2762                         p=(unsigned char *)s->init_buf->data;
2763                         }
2764
2765                 /* Compute the shared pre-master secret */
2766                 field_size = EC_GROUP_get_degree(group);
2767                 if (field_size <= 0)
2768                         {
2769                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE, 
2770                                ERR_R_ECDH_LIB);
2771                         goto err;
2772                         }
2773                 i = ECDH_compute_key(p, (field_size+7)/8, clnt_ecpoint, srvr_ecdh, NULL);
2774                 if (i <= 0)
2775                         {
2776                         SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2777                             ERR_R_ECDH_LIB);
2778                         goto err;
2779                         }
2780
2781                 EVP_PKEY_free(clnt_pub_pkey);
2782                 EC_POINT_free(clnt_ecpoint);
2783                 EC_KEY_free(srvr_ecdh);
2784                 BN_CTX_free(bn_ctx);
2785                 EC_KEY_free(s->s3->tmp.ecdh);
2786                 s->s3->tmp.ecdh = NULL; 
2787
2788                 /* Compute the master secret */
2789                 s->session->master_key_length = s->method->ssl3_enc-> \
2790                     generate_master_secret(s, s->session->master_key, p, i);
2791                 
2792                 OPENSSL_cleanse(p, i);
2793                 return (ret);
2794                 }
2795         else
2796 #endif
2797 #ifndef OPENSSL_NO_PSK
2798                 if (alg_k & SSL_kPSK)
2799                         {
2800                         unsigned char *t = NULL;
2801                         unsigned char psk_or_pre_ms[PSK_MAX_PSK_LEN*2+4];
2802                         unsigned int pre_ms_len = 0, psk_len = 0;
2803                         int psk_err = 1;
2804                         char tmp_id[PSK_MAX_IDENTITY_LEN+1];
2805
2806                         al=SSL_AD_HANDSHAKE_FAILURE;
2807
2808                         n2s(p,i);
2809                         if (n != i+2)
2810                                 {
2811                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2812                                         SSL_R_LENGTH_MISMATCH);
2813                                 goto psk_err;
2814                                 }
2815                         if (i > PSK_MAX_IDENTITY_LEN)
2816                                 {
2817                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2818                                         SSL_R_DATA_LENGTH_TOO_LONG);
2819                                 goto psk_err;
2820                                 }
2821                         if (s->psk_server_callback == NULL)
2822                                 {
2823                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2824                                        SSL_R_PSK_NO_SERVER_CB);
2825                                 goto psk_err;
2826                                 }
2827
2828                         /* Create guaranteed NULL-terminated identity
2829                          * string for the callback */
2830                         memcpy(tmp_id, p, i);
2831                         memset(tmp_id+i, 0, PSK_MAX_IDENTITY_LEN+1-i);
2832                         psk_len = s->psk_server_callback(s, tmp_id,
2833                                 psk_or_pre_ms, sizeof(psk_or_pre_ms));
2834                         OPENSSL_cleanse(tmp_id, PSK_MAX_IDENTITY_LEN+1);
2835
2836                         if (psk_len > PSK_MAX_PSK_LEN)
2837                                 {
2838                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2839                                         ERR_R_INTERNAL_ERROR);
2840                                 goto psk_err;
2841                                 }
2842                         else if (psk_len == 0)
2843                                 {
2844                                 /* PSK related to the given identity not found */
2845                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2846                                        SSL_R_PSK_IDENTITY_NOT_FOUND);
2847                                 al=SSL_AD_UNKNOWN_PSK_IDENTITY;
2848                                 goto psk_err;
2849                                 }
2850
2851                         /* create PSK pre_master_secret */
2852                         pre_ms_len=2+psk_len+2+psk_len;
2853                         t = psk_or_pre_ms;
2854                         memmove(psk_or_pre_ms+psk_len+4, psk_or_pre_ms, psk_len);
2855                         s2n(psk_len, t);
2856                         memset(t, 0, psk_len);
2857                         t+=psk_len;
2858                         s2n(psk_len, t);
2859
2860                         if (s->session->psk_identity != NULL)
2861                                 OPENSSL_free(s->session->psk_identity);
2862                         s->session->psk_identity = BUF_strdup((char *)p);
2863                         if (s->session->psk_identity == NULL)
2864                                 {
2865                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2866                                         ERR_R_MALLOC_FAILURE);
2867                                 goto psk_err;
2868                                 }
2869
2870                         if (s->session->psk_identity_hint != NULL)
2871                                 OPENSSL_free(s->session->psk_identity_hint);
2872                         s->session->psk_identity_hint = BUF_strdup(s->ctx->psk_identity_hint);
2873                         if (s->ctx->psk_identity_hint != NULL &&
2874                                 s->session->psk_identity_hint == NULL)
2875                                 {
2876                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
2877                                         ERR_R_MALLOC_FAILURE);
2878                                 goto psk_err;
2879                                 }
2880
2881                         s->session->master_key_length=
2882                                 s->method->ssl3_enc->generate_master_secret(s,
2883                                         s->session->master_key, psk_or_pre_ms, pre_ms_len);
2884                         psk_err = 0;
2885                 psk_err:
2886                         OPENSSL_cleanse(psk_or_pre_ms, sizeof(psk_or_pre_ms));
2887                         if (psk_err != 0)
2888                                 goto f_err;
2889                         }
2890                 else
2891 #endif
2892 #ifndef OPENSSL_NO_SRP
2893                 if (alg_k & SSL_kSRP)
2894                         {
2895                         int param_len;
2896
2897                         n2s(p,i);
2898                         param_len=i+2;
2899                         if (param_len > n)
2900                                 {
2901                                 al=SSL_AD_DECODE_ERROR;
2902                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_BAD_SRP_A_LENGTH);
2903                                 goto f_err;
2904                                 }
2905                         if (!(s->srp_ctx.A=BN_bin2bn(p,i,NULL)))
2906                                 {
2907                                 SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,ERR_R_BN_LIB);
2908                                 goto err;
2909                                 }
2910                         if (BN_ucmp(s->srp_ctx.A, s->srp_ctx.N) >= 0
2911                                 || BN_is_zero(s->srp_ctx.A))
2912                    &