PR: 2295
[openssl.git] / ssl / t1_lib.c
1 /* ssl/t1_lib.c */
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 #include <stdio.h>
113 #include <openssl/objects.h>
114 #include <openssl/evp.h>
115 #include <openssl/hmac.h>
116 #include <openssl/ocsp.h>
117 #include "ssl_locl.h"
118
119 const char tls1_version_str[]="TLSv1" OPENSSL_VERSION_PTEXT;
120
121 #ifndef OPENSSL_NO_TLSEXT
122 static int tls_decrypt_ticket(SSL *s, const unsigned char *tick, int ticklen,
123                                 const unsigned char *sess_id, int sesslen,
124                                 SSL_SESSION **psess);
125 #endif
126
127 SSL3_ENC_METHOD TLSv1_enc_data={
128         tls1_enc,
129         tls1_mac,
130         tls1_setup_key_block,
131         tls1_generate_master_secret,
132         tls1_change_cipher_state,
133         tls1_final_finish_mac,
134         TLS1_FINISH_MAC_LENGTH,
135         tls1_cert_verify_mac,
136         TLS_MD_CLIENT_FINISH_CONST,TLS_MD_CLIENT_FINISH_CONST_SIZE,
137         TLS_MD_SERVER_FINISH_CONST,TLS_MD_SERVER_FINISH_CONST_SIZE,
138         tls1_alert_code,
139         };
140
141 long tls1_default_timeout(void)
142         {
143         /* 2 hours, the 24 hours mentioned in the TLSv1 spec
144          * is way too long for http, the cache would over fill */
145         return(60*60*2);
146         }
147
148 int tls1_new(SSL *s)
149         {
150         if (!ssl3_new(s)) return(0);
151         s->method->ssl_clear(s);
152         return(1);
153         }
154
155 void tls1_free(SSL *s)
156         {
157 #ifndef OPENSSL_NO_TLSEXT
158         if (s->tlsext_session_ticket)
159                 {
160                 OPENSSL_free(s->tlsext_session_ticket);
161                 }
162 #endif /* OPENSSL_NO_TLSEXT */
163         ssl3_free(s);
164         }
165
166 void tls1_clear(SSL *s)
167         {
168         ssl3_clear(s);
169         s->version = s->method->version;
170         }
171
172 #ifndef OPENSSL_NO_EC
173 static int nid_list[] =
174         {
175                 NID_sect163k1, /* sect163k1 (1) */
176                 NID_sect163r1, /* sect163r1 (2) */
177                 NID_sect163r2, /* sect163r2 (3) */
178                 NID_sect193r1, /* sect193r1 (4) */ 
179                 NID_sect193r2, /* sect193r2 (5) */ 
180                 NID_sect233k1, /* sect233k1 (6) */
181                 NID_sect233r1, /* sect233r1 (7) */ 
182                 NID_sect239k1, /* sect239k1 (8) */ 
183                 NID_sect283k1, /* sect283k1 (9) */
184                 NID_sect283r1, /* sect283r1 (10) */ 
185                 NID_sect409k1, /* sect409k1 (11) */ 
186                 NID_sect409r1, /* sect409r1 (12) */
187                 NID_sect571k1, /* sect571k1 (13) */ 
188                 NID_sect571r1, /* sect571r1 (14) */ 
189                 NID_secp160k1, /* secp160k1 (15) */
190                 NID_secp160r1, /* secp160r1 (16) */ 
191                 NID_secp160r2, /* secp160r2 (17) */ 
192                 NID_secp192k1, /* secp192k1 (18) */
193                 NID_X9_62_prime192v1, /* secp192r1 (19) */ 
194                 NID_secp224k1, /* secp224k1 (20) */ 
195                 NID_secp224r1, /* secp224r1 (21) */
196                 NID_secp256k1, /* secp256k1 (22) */ 
197                 NID_X9_62_prime256v1, /* secp256r1 (23) */ 
198                 NID_secp384r1, /* secp384r1 (24) */
199                 NID_secp521r1  /* secp521r1 (25) */     
200         };
201         
202 int tls1_ec_curve_id2nid(int curve_id)
203         {
204         /* ECC curves from draft-ietf-tls-ecc-12.txt (Oct. 17, 2005) */
205         if ((curve_id < 1) || ((unsigned int)curve_id >
206                                 sizeof(nid_list)/sizeof(nid_list[0])))
207                 return 0;
208         return nid_list[curve_id-1];
209         }
210
211 int tls1_ec_nid2curve_id(int nid)
212         {
213         /* ECC curves from draft-ietf-tls-ecc-12.txt (Oct. 17, 2005) */
214         switch (nid)
215                 {
216         case NID_sect163k1: /* sect163k1 (1) */
217                 return 1;
218         case NID_sect163r1: /* sect163r1 (2) */
219                 return 2;
220         case NID_sect163r2: /* sect163r2 (3) */
221                 return 3;
222         case NID_sect193r1: /* sect193r1 (4) */ 
223                 return 4;
224         case NID_sect193r2: /* sect193r2 (5) */ 
225                 return 5;
226         case NID_sect233k1: /* sect233k1 (6) */
227                 return 6;
228         case NID_sect233r1: /* sect233r1 (7) */ 
229                 return 7;
230         case NID_sect239k1: /* sect239k1 (8) */ 
231                 return 8;
232         case NID_sect283k1: /* sect283k1 (9) */
233                 return 9;
234         case NID_sect283r1: /* sect283r1 (10) */ 
235                 return 10;
236         case NID_sect409k1: /* sect409k1 (11) */ 
237                 return 11;
238         case NID_sect409r1: /* sect409r1 (12) */
239                 return 12;
240         case NID_sect571k1: /* sect571k1 (13) */ 
241                 return 13;
242         case NID_sect571r1: /* sect571r1 (14) */ 
243                 return 14;
244         case NID_secp160k1: /* secp160k1 (15) */
245                 return 15;
246         case NID_secp160r1: /* secp160r1 (16) */ 
247                 return 16;
248         case NID_secp160r2: /* secp160r2 (17) */ 
249                 return 17;
250         case NID_secp192k1: /* secp192k1 (18) */
251                 return 18;
252         case NID_X9_62_prime192v1: /* secp192r1 (19) */ 
253                 return 19;
254         case NID_secp224k1: /* secp224k1 (20) */ 
255                 return 20;
256         case NID_secp224r1: /* secp224r1 (21) */
257                 return 21;
258         case NID_secp256k1: /* secp256k1 (22) */ 
259                 return 22;
260         case NID_X9_62_prime256v1: /* secp256r1 (23) */ 
261                 return 23;
262         case NID_secp384r1: /* secp384r1 (24) */
263                 return 24;
264         case NID_secp521r1:  /* secp521r1 (25) */       
265                 return 25;
266         default:
267                 return 0;
268                 }
269         }
270 #endif /* OPENSSL_NO_EC */
271
272 #ifndef OPENSSL_NO_TLSEXT
273
274 /* List of supported signature algorithms and hashes. Should make this
275  * customisable at some point, for now include everything we support.
276  */
277
278 #ifdef OPENSSL_NO_RSA
279 #define tlsext_sigalg_rsa(md) /* */
280 #else
281 #define tlsext_sigalg_rsa(md) md, TLSEXT_signature_rsa,
282 #endif
283
284 #ifdef OPENSSL_NO_DSA
285 #define tlsext_sigalg_dsa(md) /* */
286 #else
287 #define tlsext_sigalg_dsa(md) md, TLSEXT_signature_dsa,
288 #endif
289
290 #ifdef OPENSSL_NO_ECDSA
291 #define tlsext_sigalg_ecdsa(md) /* */
292 #else
293 #define tlsext_sigalg_ecdsa(md) md, TLSEXT_signature_dsa,
294 #endif
295
296 #define tlsext_sigalg(md) \
297                 tlsext_sigalg_rsa(md) \
298                 tlsext_sigalg_dsa(md) \
299                 tlsext_sigalg_ecdsa(md)
300
301 static unsigned char tls12_sigalgs[] = {
302 #ifndef OPENSSL_NO_SHA512
303         tlsext_sigalg(TLSEXT_hash_sha512)
304         tlsext_sigalg(TLSEXT_hash_sha384)
305 #endif
306 #ifndef OPENSSL_NO_SHA256
307         tlsext_sigalg(TLSEXT_hash_sha256)
308         tlsext_sigalg(TLSEXT_hash_sha224)
309 #endif
310 #ifndef OPENSSL_NO_SHA
311         tlsext_sigalg(TLSEXT_hash_sha1)
312 #endif
313 #ifndef OPENSSL_NO_MD5
314         tlsext_sigalg_rsa(TLSEXT_hash_md5)
315 #endif
316 };
317
318 int tls12_get_req_sig_algs(SSL *s, unsigned char *p)
319         {
320         if (p)
321                 memcpy(p, tls12_sigalgs, sizeof(tls12_sigalgs));
322         return (int)sizeof(tls12_sigalgs);
323         }
324
325 unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned char *limit)
326         {
327         int extdatalen=0;
328         unsigned char *ret = p;
329
330         /* don't add extensions for SSLv3 unless doing secure renegotiation */
331         if (s->client_version == SSL3_VERSION
332                                         && !s->s3->send_connection_binding)
333                 return p;
334
335         ret+=2;
336
337         if (ret>=limit) return NULL; /* this really never occurs, but ... */
338
339         if (s->tlsext_hostname != NULL)
340                 { 
341                 /* Add TLS extension servername to the Client Hello message */
342                 unsigned long size_str;
343                 long lenmax; 
344
345                 /* check for enough space.
346                    4 for the servername type and entension length
347                    2 for servernamelist length
348                    1 for the hostname type
349                    2 for hostname length
350                    + hostname length 
351                 */
352                    
353                 if ((lenmax = limit - ret - 9) < 0 
354                     || (size_str = strlen(s->tlsext_hostname)) > (unsigned long)lenmax) 
355                         return NULL;
356                         
357                 /* extension type and length */
358                 s2n(TLSEXT_TYPE_server_name,ret); 
359                 s2n(size_str+5,ret);
360                 
361                 /* length of servername list */
362                 s2n(size_str+3,ret);
363         
364                 /* hostname type, length and hostname */
365                 *(ret++) = (unsigned char) TLSEXT_NAMETYPE_host_name;
366                 s2n(size_str,ret);
367                 memcpy(ret, s->tlsext_hostname, size_str);
368                 ret+=size_str;
369                 }
370
371         /* Add RI if renegotiating */
372         if (s->renegotiate)
373           {
374           int el;
375           
376           if(!ssl_add_clienthello_renegotiate_ext(s, 0, &el, 0))
377               {
378               SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
379               return NULL;
380               }
381
382           if((limit - p - 4 - el) < 0) return NULL;
383           
384           s2n(TLSEXT_TYPE_renegotiate,ret);
385           s2n(el,ret);
386
387           if(!ssl_add_clienthello_renegotiate_ext(s, ret, &el, el))
388               {
389               SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
390               return NULL;
391               }
392
393           ret += el;
394         }
395
396 #ifndef OPENSSL_NO_SRP
397 #define MIN(x,y) (((x)<(y))?(x):(y))
398         /* we add SRP username the first time only if we have one! */
399         if (s->srp_ctx.login != NULL)
400                 {/* Add TLS extension SRP username to the Client Hello message */
401                 int login_len = MIN(strlen(s->srp_ctx.login) + 1, 255);
402                 long lenmax; 
403
404                 if ((lenmax = limit - ret - 5) < 0) return NULL; 
405                 if (login_len > lenmax) return NULL;
406                 if (login_len > 255)
407                         {
408                         SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
409                         return NULL;
410                         }
411                 s2n(TLSEXT_TYPE_srp,ret);
412                 s2n(login_len+1,ret);
413
414                 (*ret++) = (unsigned char) MIN(strlen(s->srp_ctx.login), 254);
415                 memcpy(ret, s->srp_ctx.login, MIN(strlen(s->srp_ctx.login), 254));
416                 ret+=login_len;
417                 }
418 #endif
419
420 #ifndef OPENSSL_NO_EC
421         if (s->tlsext_ecpointformatlist != NULL &&
422             s->version != DTLS1_VERSION)
423                 {
424                 /* Add TLS extension ECPointFormats to the ClientHello message */
425                 long lenmax; 
426
427                 if ((lenmax = limit - ret - 5) < 0) return NULL; 
428                 if (s->tlsext_ecpointformatlist_length > (unsigned long)lenmax) return NULL;
429                 if (s->tlsext_ecpointformatlist_length > 255)
430                         {
431                         SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
432                         return NULL;
433                         }
434                 
435                 s2n(TLSEXT_TYPE_ec_point_formats,ret);
436                 s2n(s->tlsext_ecpointformatlist_length + 1,ret);
437                 *(ret++) = (unsigned char) s->tlsext_ecpointformatlist_length;
438                 memcpy(ret, s->tlsext_ecpointformatlist, s->tlsext_ecpointformatlist_length);
439                 ret+=s->tlsext_ecpointformatlist_length;
440                 }
441         if (s->tlsext_ellipticcurvelist != NULL &&
442             s->version != DTLS1_VERSION)
443                 {
444                 /* Add TLS extension EllipticCurves to the ClientHello message */
445                 long lenmax; 
446
447                 if ((lenmax = limit - ret - 6) < 0) return NULL; 
448                 if (s->tlsext_ellipticcurvelist_length > (unsigned long)lenmax) return NULL;
449                 if (s->tlsext_ellipticcurvelist_length > 65532)
450                         {
451                         SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
452                         return NULL;
453                         }
454                 
455                 s2n(TLSEXT_TYPE_elliptic_curves,ret);
456                 s2n(s->tlsext_ellipticcurvelist_length + 2, ret);
457
458                 /* NB: draft-ietf-tls-ecc-12.txt uses a one-byte prefix for
459                  * elliptic_curve_list, but the examples use two bytes.
460                  * http://www1.ietf.org/mail-archive/web/tls/current/msg00538.html
461                  * resolves this to two bytes.
462                  */
463                 s2n(s->tlsext_ellipticcurvelist_length, ret);
464                 memcpy(ret, s->tlsext_ellipticcurvelist, s->tlsext_ellipticcurvelist_length);
465                 ret+=s->tlsext_ellipticcurvelist_length;
466                 }
467 #endif /* OPENSSL_NO_EC */
468
469         if (!(SSL_get_options(s) & SSL_OP_NO_TICKET))
470                 {
471                 int ticklen;
472                 if (!s->new_session && s->session && s->session->tlsext_tick)
473                         ticklen = s->session->tlsext_ticklen;
474                 else if (s->session && s->tlsext_session_ticket &&
475                          s->tlsext_session_ticket->data)
476                         {
477                         ticklen = s->tlsext_session_ticket->length;
478                         s->session->tlsext_tick = OPENSSL_malloc(ticklen);
479                         if (!s->session->tlsext_tick)
480                                 return NULL;
481                         memcpy(s->session->tlsext_tick,
482                                s->tlsext_session_ticket->data,
483                                ticklen);
484                         s->session->tlsext_ticklen = ticklen;
485                         }
486                 else
487                         ticklen = 0;
488                 if (ticklen == 0 && s->tlsext_session_ticket &&
489                     s->tlsext_session_ticket->data == NULL)
490                         goto skip_ext;
491                 /* Check for enough room 2 for extension type, 2 for len
492                  * rest for ticket
493                  */
494                 if ((long)(limit - ret - 4 - ticklen) < 0) return NULL;
495                 s2n(TLSEXT_TYPE_session_ticket,ret); 
496                 s2n(ticklen,ret);
497                 if (ticklen)
498                         {
499                         memcpy(ret, s->session->tlsext_tick, ticklen);
500                         ret += ticklen;
501                         }
502                 }
503                 skip_ext:
504
505         if (s->version >= TLS1_2_VERSION)
506                 {
507                 if ((size_t)(limit - ret) < sizeof(tls12_sigalgs) + 6)
508                         return NULL; 
509                 s2n(TLSEXT_TYPE_signature_algorithms,ret);
510                 s2n(sizeof(tls12_sigalgs) + 2, ret);
511                 s2n(sizeof(tls12_sigalgs), ret);
512                 memcpy(ret, tls12_sigalgs, sizeof(tls12_sigalgs));
513                 ret += sizeof(tls12_sigalgs);
514                 }
515
516 #ifdef TLSEXT_TYPE_opaque_prf_input
517         if (s->s3->client_opaque_prf_input != NULL &&
518             s->version != DTLS1_VERSION)
519                 {
520                 size_t col = s->s3->client_opaque_prf_input_len;
521                 
522                 if ((long)(limit - ret - 6 - col < 0))
523                         return NULL;
524                 if (col > 0xFFFD) /* can't happen */
525                         return NULL;
526
527                 s2n(TLSEXT_TYPE_opaque_prf_input, ret); 
528                 s2n(col + 2, ret);
529                 s2n(col, ret);
530                 memcpy(ret, s->s3->client_opaque_prf_input, col);
531                 ret += col;
532                 }
533 #endif
534
535         if (s->tlsext_status_type == TLSEXT_STATUSTYPE_ocsp &&
536             s->version != DTLS1_VERSION)
537                 {
538                 int i;
539                 long extlen, idlen, itmp;
540                 OCSP_RESPID *id;
541
542                 idlen = 0;
543                 for (i = 0; i < sk_OCSP_RESPID_num(s->tlsext_ocsp_ids); i++)
544                         {
545                         id = sk_OCSP_RESPID_value(s->tlsext_ocsp_ids, i);
546                         itmp = i2d_OCSP_RESPID(id, NULL);
547                         if (itmp <= 0)
548                                 return NULL;
549                         idlen += itmp + 2;
550                         }
551
552                 if (s->tlsext_ocsp_exts)
553                         {
554                         extlen = i2d_X509_EXTENSIONS(s->tlsext_ocsp_exts, NULL);
555                         if (extlen < 0)
556                                 return NULL;
557                         }
558                 else
559                         extlen = 0;
560                         
561                 if ((long)(limit - ret - 7 - extlen - idlen) < 0) return NULL;
562                 s2n(TLSEXT_TYPE_status_request, ret);
563                 if (extlen + idlen > 0xFFF0)
564                         return NULL;
565                 s2n(extlen + idlen + 5, ret);
566                 *(ret++) = TLSEXT_STATUSTYPE_ocsp;
567                 s2n(idlen, ret);
568                 for (i = 0; i < sk_OCSP_RESPID_num(s->tlsext_ocsp_ids); i++)
569                         {
570                         /* save position of id len */
571                         unsigned char *q = ret;
572                         id = sk_OCSP_RESPID_value(s->tlsext_ocsp_ids, i);
573                         /* skip over id len */
574                         ret += 2;
575                         itmp = i2d_OCSP_RESPID(id, &ret);
576                         /* write id len */
577                         s2n(itmp, q);
578                         }
579                 s2n(extlen, ret);
580                 if (extlen > 0)
581                         i2d_X509_EXTENSIONS(s->tlsext_ocsp_exts, &ret);
582                 }
583
584 #ifndef OPENSSL_NO_NEXTPROTONEG
585         if (s->ctx->next_proto_select_cb && !s->s3->tmp.finish_md_len)
586                 {
587                 /* The client advertises an emtpy extension to indicate its
588                  * support for Next Protocol Negotiation */
589                 if (limit - ret - 4 < 0)
590                         return NULL;
591                 s2n(TLSEXT_TYPE_next_proto_neg,ret);
592                 s2n(0,ret);
593                 }
594 #endif
595
596         if ((extdatalen = ret-p-2)== 0) 
597                 return p;
598
599         s2n(extdatalen,p);
600         return ret;
601         }
602
603 unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *p, unsigned char *limit)
604         {
605         int extdatalen=0;
606         unsigned char *ret = p;
607 #ifndef OPENSSL_NO_NEXTPROTONEG
608         int next_proto_neg_seen;
609 #endif
610
611         /* don't add extensions for SSLv3, unless doing secure renegotiation */
612         if (s->version == SSL3_VERSION && !s->s3->send_connection_binding)
613                 return p;
614         
615         ret+=2;
616         if (ret>=limit) return NULL; /* this really never occurs, but ... */
617
618         if (!s->hit && s->servername_done == 1 && s->session->tlsext_hostname != NULL)
619                 { 
620                 if ((long)(limit - ret - 4) < 0) return NULL; 
621
622                 s2n(TLSEXT_TYPE_server_name,ret);
623                 s2n(0,ret);
624                 }
625
626         if(s->s3->send_connection_binding)
627         {
628           int el;
629           
630           if(!ssl_add_serverhello_renegotiate_ext(s, 0, &el, 0))
631               {
632               SSLerr(SSL_F_SSL_ADD_SERVERHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
633               return NULL;
634               }
635
636           if((limit - p - 4 - el) < 0) return NULL;
637           
638           s2n(TLSEXT_TYPE_renegotiate,ret);
639           s2n(el,ret);
640
641           if(!ssl_add_serverhello_renegotiate_ext(s, ret, &el, el))
642               {
643               SSLerr(SSL_F_SSL_ADD_SERVERHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
644               return NULL;
645               }
646
647           ret += el;
648         }
649
650 #ifndef OPENSSL_NO_EC
651         if (s->tlsext_ecpointformatlist != NULL &&
652             s->version != DTLS1_VERSION)
653                 {
654                 /* Add TLS extension ECPointFormats to the ServerHello message */
655                 long lenmax; 
656
657                 if ((lenmax = limit - ret - 5) < 0) return NULL; 
658                 if (s->tlsext_ecpointformatlist_length > (unsigned long)lenmax) return NULL;
659                 if (s->tlsext_ecpointformatlist_length > 255)
660                         {
661                         SSLerr(SSL_F_SSL_ADD_SERVERHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
662                         return NULL;
663                         }
664                 
665                 s2n(TLSEXT_TYPE_ec_point_formats,ret);
666                 s2n(s->tlsext_ecpointformatlist_length + 1,ret);
667                 *(ret++) = (unsigned char) s->tlsext_ecpointformatlist_length;
668                 memcpy(ret, s->tlsext_ecpointformatlist, s->tlsext_ecpointformatlist_length);
669                 ret+=s->tlsext_ecpointformatlist_length;
670
671                 }
672         /* Currently the server should not respond with a SupportedCurves extension */
673 #endif /* OPENSSL_NO_EC */
674
675         if (s->tlsext_ticket_expected
676                 && !(SSL_get_options(s) & SSL_OP_NO_TICKET)) 
677                 { 
678                 if ((long)(limit - ret - 4) < 0) return NULL; 
679                 s2n(TLSEXT_TYPE_session_ticket,ret);
680                 s2n(0,ret);
681                 }
682
683         if (s->tlsext_status_expected)
684                 { 
685                 if ((long)(limit - ret - 4) < 0) return NULL; 
686                 s2n(TLSEXT_TYPE_status_request,ret);
687                 s2n(0,ret);
688                 }
689
690 #ifdef TLSEXT_TYPE_opaque_prf_input
691         if (s->s3->server_opaque_prf_input != NULL &&
692             s->version != DTLS1_VERSION)
693                 {
694                 size_t sol = s->s3->server_opaque_prf_input_len;
695                 
696                 if ((long)(limit - ret - 6 - sol) < 0)
697                         return NULL;
698                 if (sol > 0xFFFD) /* can't happen */
699                         return NULL;
700
701                 s2n(TLSEXT_TYPE_opaque_prf_input, ret); 
702                 s2n(sol + 2, ret);
703                 s2n(sol, ret);
704                 memcpy(ret, s->s3->server_opaque_prf_input, sol);
705                 ret += sol;
706                 }
707 #endif
708         if (((s->s3->tmp.new_cipher->id & 0xFFFF)==0x80 || (s->s3->tmp.new_cipher->id & 0xFFFF)==0x81) 
709                 && (SSL_get_options(s) & SSL_OP_CRYPTOPRO_TLSEXT_BUG))
710                 { const unsigned char cryptopro_ext[36] = {
711                         0xfd, 0xe8, /*65000*/
712                         0x00, 0x20, /*32 bytes length*/
713                         0x30, 0x1e, 0x30, 0x08, 0x06, 0x06, 0x2a, 0x85, 
714                         0x03,   0x02, 0x02, 0x09, 0x30, 0x08, 0x06, 0x06, 
715                         0x2a, 0x85, 0x03, 0x02, 0x02, 0x16, 0x30, 0x08, 
716                         0x06, 0x06, 0x2a, 0x85, 0x03, 0x02, 0x02, 0x17};
717                         if (limit-ret<36) return NULL;
718                         memcpy(ret,cryptopro_ext,36);
719                         ret+=36;
720
721                 }
722
723 #ifndef OPENSSL_NO_NEXTPROTONEG
724         next_proto_neg_seen = s->s3->next_proto_neg_seen;
725         s->s3->next_proto_neg_seen = 0;
726         if (next_proto_neg_seen && s->ctx->next_protos_advertised_cb)
727                 {
728                 const unsigned char *npa;
729                 unsigned int npalen;
730                 int r;
731
732                 r = s->ctx->next_protos_advertised_cb(s, &npa, &npalen, s->ctx->next_protos_advertised_cb_arg);
733                 if (r == SSL_TLSEXT_ERR_OK)
734                         {
735                         if ((long)(limit - ret - 4 - npalen) < 0) return NULL;
736                         s2n(TLSEXT_TYPE_next_proto_neg,ret);
737                         s2n(npalen,ret);
738                         memcpy(ret, npa, npalen);
739                         ret += npalen;
740                         s->s3->next_proto_neg_seen = 1;
741                         }
742                 }
743 #endif
744
745         if ((extdatalen = ret-p-2)== 0) 
746                 return p;
747
748         s2n(extdatalen,p);
749         return ret;
750         }
751
752 int ssl_parse_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char *d, int n, int *al)
753         {
754         unsigned short type;
755         unsigned short size;
756         unsigned short len;
757         unsigned char *data = *p;
758         int renegotiate_seen = 0;
759         int sigalg_seen = 0;
760
761         s->servername_done = 0;
762         s->tlsext_status_type = -1;
763
764         if (data >= (d+n-2))
765                 goto ri_check;
766         n2s(data,len);
767
768         if (data > (d+n-len)) 
769                 goto ri_check;
770
771         while (data <= (d+n-4))
772                 {
773                 n2s(data,type);
774                 n2s(data,size);
775
776                 if (data+size > (d+n))
777                         goto ri_check;
778 #if 0
779                 fprintf(stderr,"Received extension type %d size %d\n",type,size);
780 #endif
781                 if (s->tlsext_debug_cb)
782                         s->tlsext_debug_cb(s, 0, type, data, size,
783                                                 s->tlsext_debug_arg);
784 /* The servername extension is treated as follows:
785
786    - Only the hostname type is supported with a maximum length of 255.
787    - The servername is rejected if too long or if it contains zeros,
788      in which case an fatal alert is generated.
789    - The servername field is maintained together with the session cache.
790    - When a session is resumed, the servername call back invoked in order
791      to allow the application to position itself to the right context. 
792    - The servername is acknowledged if it is new for a session or when 
793      it is identical to a previously used for the same session. 
794      Applications can control the behaviour.  They can at any time
795      set a 'desirable' servername for a new SSL object. This can be the
796      case for example with HTTPS when a Host: header field is received and
797      a renegotiation is requested. In this case, a possible servername
798      presented in the new client hello is only acknowledged if it matches
799      the value of the Host: field. 
800    - Applications must  use SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION
801      if they provide for changing an explicit servername context for the session,
802      i.e. when the session has been established with a servername extension. 
803    - On session reconnect, the servername extension may be absent. 
804
805 */      
806
807                 if (type == TLSEXT_TYPE_server_name)
808                         {
809                         unsigned char *sdata;
810                         int servname_type;
811                         int dsize; 
812                 
813                         if (size < 2) 
814                                 {
815                                 *al = SSL_AD_DECODE_ERROR;
816                                 return 0;
817                                 }
818                         n2s(data,dsize);  
819                         size -= 2;
820                         if (dsize > size  ) 
821                                 {
822                                 *al = SSL_AD_DECODE_ERROR;
823                                 return 0;
824                                 } 
825
826                         sdata = data;
827                         while (dsize > 3) 
828                                 {
829                                 servname_type = *(sdata++); 
830                                 n2s(sdata,len);
831                                 dsize -= 3;
832
833                                 if (len > dsize) 
834                                         {
835                                         *al = SSL_AD_DECODE_ERROR;
836                                         return 0;
837                                         }
838                                 if (s->servername_done == 0)
839                                 switch (servname_type)
840                                         {
841                                 case TLSEXT_NAMETYPE_host_name:
842                                         if (!s->hit)
843                                                 {
844                                                 if(s->session->tlsext_hostname)
845                                                         {
846                                                         *al = SSL_AD_DECODE_ERROR;
847                                                         return 0;
848                                                         }
849                                                 if (len > TLSEXT_MAXLEN_host_name)
850                                                         {
851                                                         *al = TLS1_AD_UNRECOGNIZED_NAME;
852                                                         return 0;
853                                                         }
854                                                 if ((s->session->tlsext_hostname = OPENSSL_malloc(len+1)) == NULL)
855                                                         {
856                                                         *al = TLS1_AD_INTERNAL_ERROR;
857                                                         return 0;
858                                                         }
859                                                 memcpy(s->session->tlsext_hostname, sdata, len);
860                                                 s->session->tlsext_hostname[len]='\0';
861                                                 if (strlen(s->session->tlsext_hostname) != len) {
862                                                         OPENSSL_free(s->session->tlsext_hostname);
863                                                         s->session->tlsext_hostname = NULL;
864                                                         *al = TLS1_AD_UNRECOGNIZED_NAME;
865                                                         return 0;
866                                                 }
867                                                 s->servername_done = 1; 
868
869                                                 }
870                                         else 
871                                                 s->servername_done = s->session->tlsext_hostname
872                                                         && strlen(s->session->tlsext_hostname) == len 
873                                                         && strncmp(s->session->tlsext_hostname, (char *)sdata, len) == 0;
874                                         
875                                         break;
876
877                                 default:
878                                         break;
879                                         }
880                                  
881                                 dsize -= len;
882                                 }
883                         if (dsize != 0) 
884                                 {
885                                 *al = SSL_AD_DECODE_ERROR;
886                                 return 0;
887                                 }
888
889                         }
890 #ifndef OPENSSL_NO_SRP
891                 else if (type == TLSEXT_TYPE_srp)
892                         {
893                         if (size > 0)
894                                 {
895                                 len = data[0];
896                                 if ((s->srp_ctx.login = OPENSSL_malloc(len+1)) == NULL)
897                                         return -1;
898                                 memcpy(s->srp_ctx.login, &data[1], len);
899                                 s->srp_ctx.login[len]='\0';  
900                                 }
901                         }
902 #endif
903
904 #ifndef OPENSSL_NO_EC
905                 else if (type == TLSEXT_TYPE_ec_point_formats &&
906                      s->version != DTLS1_VERSION)
907                         {
908                         unsigned char *sdata = data;
909                         int ecpointformatlist_length = *(sdata++);
910
911                         if (ecpointformatlist_length != size - 1)
912                                 {
913                                 *al = TLS1_AD_DECODE_ERROR;
914                                 return 0;
915                                 }
916                         if (!s->hit)
917                                 {
918                                 if(s->session->tlsext_ecpointformatlist)
919                                         {
920                                         OPENSSL_free(s->session->tlsext_ecpointformatlist);
921                                         s->session->tlsext_ecpointformatlist = NULL;
922                                         }
923                                 s->session->tlsext_ecpointformatlist_length = 0;
924                                 if ((s->session->tlsext_ecpointformatlist = OPENSSL_malloc(ecpointformatlist_length)) == NULL)
925                                         {
926                                         *al = TLS1_AD_INTERNAL_ERROR;
927                                         return 0;
928                                         }
929                                 s->session->tlsext_ecpointformatlist_length = ecpointformatlist_length;
930                                 memcpy(s->session->tlsext_ecpointformatlist, sdata, ecpointformatlist_length);
931                                 }
932 #if 0
933                         fprintf(stderr,"ssl_parse_clienthello_tlsext s->session->tlsext_ecpointformatlist (length=%i) ", s->session->tlsext_ecpointformatlist_length);
934                         sdata = s->session->tlsext_ecpointformatlist;
935                         for (i = 0; i < s->session->tlsext_ecpointformatlist_length; i++)
936                                 fprintf(stderr,"%i ",*(sdata++));
937                         fprintf(stderr,"\n");
938 #endif
939                         }
940                 else if (type == TLSEXT_TYPE_elliptic_curves &&
941                      s->version != DTLS1_VERSION)
942                         {
943                         unsigned char *sdata = data;
944                         int ellipticcurvelist_length = (*(sdata++) << 8);
945                         ellipticcurvelist_length += (*(sdata++));
946
947                         if (ellipticcurvelist_length != size - 2)
948                                 {
949                                 *al = TLS1_AD_DECODE_ERROR;
950                                 return 0;
951                                 }
952                         if (!s->hit)
953                                 {
954                                 if(s->session->tlsext_ellipticcurvelist)
955                                         {
956                                         *al = TLS1_AD_DECODE_ERROR;
957                                         return 0;
958                                         }
959                                 s->session->tlsext_ellipticcurvelist_length = 0;
960                                 if ((s->session->tlsext_ellipticcurvelist = OPENSSL_malloc(ellipticcurvelist_length)) == NULL)
961                                         {
962                                         *al = TLS1_AD_INTERNAL_ERROR;
963                                         return 0;
964                                         }
965                                 s->session->tlsext_ellipticcurvelist_length = ellipticcurvelist_length;
966                                 memcpy(s->session->tlsext_ellipticcurvelist, sdata, ellipticcurvelist_length);
967                                 }
968 #if 0
969                         fprintf(stderr,"ssl_parse_clienthello_tlsext s->session->tlsext_ellipticcurvelist (length=%i) ", s->session->tlsext_ellipticcurvelist_length);
970                         sdata = s->session->tlsext_ellipticcurvelist;
971                         for (i = 0; i < s->session->tlsext_ellipticcurvelist_length; i++)
972                                 fprintf(stderr,"%i ",*(sdata++));
973                         fprintf(stderr,"\n");
974 #endif
975                         }
976 #endif /* OPENSSL_NO_EC */
977 #ifdef TLSEXT_TYPE_opaque_prf_input
978                 else if (type == TLSEXT_TYPE_opaque_prf_input &&
979                      s->version != DTLS1_VERSION)
980                         {
981                         unsigned char *sdata = data;
982
983                         if (size < 2)
984                                 {
985                                 *al = SSL_AD_DECODE_ERROR;
986                                 return 0;
987                                 }
988                         n2s(sdata, s->s3->client_opaque_prf_input_len);
989                         if (s->s3->client_opaque_prf_input_len != size - 2)
990                                 {
991                                 *al = SSL_AD_DECODE_ERROR;
992                                 return 0;
993                                 }
994
995                         if (s->s3->client_opaque_prf_input != NULL) /* shouldn't really happen */
996                                 OPENSSL_free(s->s3->client_opaque_prf_input);
997                         if (s->s3->client_opaque_prf_input_len == 0)
998                                 s->s3->client_opaque_prf_input = OPENSSL_malloc(1); /* dummy byte just to get non-NULL */
999                         else
1000                                 s->s3->client_opaque_prf_input = BUF_memdup(sdata, s->s3->client_opaque_prf_input_len);
1001                         if (s->s3->client_opaque_prf_input == NULL)
1002                                 {
1003                                 *al = TLS1_AD_INTERNAL_ERROR;
1004                                 return 0;
1005                                 }
1006                         }
1007 #endif
1008                 else if (type == TLSEXT_TYPE_session_ticket)
1009                         {
1010                         if (s->tls_session_ticket_ext_cb &&
1011                             !s->tls_session_ticket_ext_cb(s, data, size, s->tls_session_ticket_ext_cb_arg))
1012                                 {
1013                                 *al = TLS1_AD_INTERNAL_ERROR;
1014                                 return 0;
1015                                 }
1016                         }
1017                 else if (type == TLSEXT_TYPE_renegotiate)
1018                         {
1019                         if(!ssl_parse_clienthello_renegotiate_ext(s, data, size, al))
1020                                 return 0;
1021                         renegotiate_seen = 1;
1022                         }
1023                 else if (type == TLSEXT_TYPE_signature_algorithms)
1024                         {
1025                         int dsize;
1026                         if (sigalg_seen || size < 2) 
1027                                 {
1028                                 *al = SSL_AD_DECODE_ERROR;
1029                                 return 0;
1030                                 }
1031                         sigalg_seen = 1;
1032                         n2s(data,dsize);
1033                         size -= 2;
1034                         if (dsize != size || dsize & 1) 
1035                                 {
1036                                 *al = SSL_AD_DECODE_ERROR;
1037                                 return 0;
1038                                 }
1039                         if (!tls1_process_sigalgs(s, data, dsize))
1040                                 {
1041                                 *al = SSL_AD_DECODE_ERROR;
1042                                 return 0;
1043                                 }
1044                         }
1045                 else if (type == TLSEXT_TYPE_status_request &&
1046                          s->version != DTLS1_VERSION && s->ctx->tlsext_status_cb)
1047                         {
1048                 
1049                         if (size < 5) 
1050                                 {
1051                                 *al = SSL_AD_DECODE_ERROR;
1052                                 return 0;
1053                                 }
1054
1055                         s->tlsext_status_type = *data++;
1056                         size--;
1057                         if (s->tlsext_status_type == TLSEXT_STATUSTYPE_ocsp)
1058                                 {
1059                                 const unsigned char *sdata;
1060                                 int dsize;
1061                                 /* Read in responder_id_list */
1062                                 n2s(data,dsize);
1063                                 size -= 2;
1064                                 if (dsize > size  ) 
1065                                         {
1066                                         *al = SSL_AD_DECODE_ERROR;
1067                                         return 0;
1068                                         }
1069                                 while (dsize > 0)
1070                                         {
1071                                         OCSP_RESPID *id;
1072                                         int idsize;
1073                                         if (dsize < 4)
1074                                                 {
1075                                                 *al = SSL_AD_DECODE_ERROR;
1076                                                 return 0;
1077                                                 }
1078                                         n2s(data, idsize);
1079                                         dsize -= 2 + idsize;
1080                                         size -= 2 + idsize;
1081                                         if (dsize < 0)
1082                                                 {
1083                                                 *al = SSL_AD_DECODE_ERROR;
1084                                                 return 0;
1085                                                 }
1086                                         sdata = data;
1087                                         data += idsize;
1088                                         id = d2i_OCSP_RESPID(NULL,
1089                                                                 &sdata, idsize);
1090                                         if (!id)
1091                                                 {
1092                                                 *al = SSL_AD_DECODE_ERROR;
1093                                                 return 0;
1094                                                 }
1095                                         if (data != sdata)
1096                                                 {
1097                                                 OCSP_RESPID_free(id);
1098                                                 *al = SSL_AD_DECODE_ERROR;
1099                                                 return 0;
1100                                                 }
1101                                         if (!s->tlsext_ocsp_ids
1102                                                 && !(s->tlsext_ocsp_ids =
1103                                                 sk_OCSP_RESPID_new_null()))
1104                                                 {
1105                                                 OCSP_RESPID_free(id);
1106                                                 *al = SSL_AD_INTERNAL_ERROR;
1107                                                 return 0;
1108                                                 }
1109                                         if (!sk_OCSP_RESPID_push(
1110                                                         s->tlsext_ocsp_ids, id))
1111                                                 {
1112                                                 OCSP_RESPID_free(id);
1113                                                 *al = SSL_AD_INTERNAL_ERROR;
1114                                                 return 0;
1115                                                 }
1116                                         }
1117
1118                                 /* Read in request_extensions */
1119                                 if (size < 2)
1120                                         {
1121                                         *al = SSL_AD_DECODE_ERROR;
1122                                         return 0;
1123                                         }
1124                                 n2s(data,dsize);
1125                                 size -= 2;
1126                                 if (dsize != size)
1127                                         {
1128                                         *al = SSL_AD_DECODE_ERROR;
1129                                         return 0;
1130                                         }
1131                                 sdata = data;
1132                                 if (dsize > 0)
1133                                         {
1134                                         s->tlsext_ocsp_exts =
1135                                                 d2i_X509_EXTENSIONS(NULL,
1136                                                         &sdata, dsize);
1137                                         if (!s->tlsext_ocsp_exts
1138                                                 || (data + dsize != sdata))
1139                                                 {
1140                                                 *al = SSL_AD_DECODE_ERROR;
1141                                                 return 0;
1142                                                 }
1143                                         }
1144                                 }
1145                                 /* We don't know what to do with any other type
1146                                 * so ignore it.
1147                                 */
1148                                 else
1149                                         s->tlsext_status_type = -1;
1150                         }
1151 #ifndef OPENSSL_NO_NEXTPROTONEG
1152                 else if (type == TLSEXT_TYPE_next_proto_neg &&
1153                          s->s3->tmp.finish_md_len == 0)
1154                         {
1155                         /* We shouldn't accept this extension on a
1156                          * renegotiation.
1157                          *
1158                          * s->new_session will be set on renegotiation, but we
1159                          * probably shouldn't rely that it couldn't be set on
1160                          * the initial renegotation too in certain cases (when
1161                          * there's some other reason to disallow resuming an
1162                          * earlier session -- the current code won't be doing
1163                          * anything like that, but this might change).
1164
1165                          * A valid sign that there's been a previous handshake
1166                          * in this connection is if s->s3->tmp.finish_md_len >
1167                          * 0.  (We are talking about a check that will happen
1168                          * in the Hello protocol round, well before a new
1169                          * Finished message could have been computed.) */
1170                         s->s3->next_proto_neg_seen = 1;
1171                         }
1172 #endif
1173
1174                 /* session ticket processed earlier */
1175                 data+=size;
1176                 }
1177                                 
1178         *p = data;
1179
1180         ri_check:
1181
1182         /* Need RI if renegotiating */
1183
1184         if (!renegotiate_seen && s->renegotiate &&
1185                 !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1186                 {
1187                 *al = SSL_AD_HANDSHAKE_FAILURE;
1188                 SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_TLSEXT,
1189                                 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
1190                 return 0;
1191                 }
1192
1193         return 1;
1194         }
1195
1196 #ifndef OPENSSL_NO_NEXTPROTONEG
1197 /* ssl_next_proto_validate validates a Next Protocol Negotiation block. No
1198  * elements of zero length are allowed and the set of elements must exactly fill
1199  * the length of the block. */
1200 static int ssl_next_proto_validate(unsigned char *d, unsigned len)
1201         {
1202         unsigned int off = 0;
1203
1204         while (off < len)
1205                 {
1206                 if (d[off] == 0)
1207                         return 0;
1208                 off += d[off];
1209                 off++;
1210                 }
1211
1212         return off == len;
1213         }
1214 #endif
1215
1216 int ssl_parse_serverhello_tlsext(SSL *s, unsigned char **p, unsigned char *d, int n, int *al)
1217         {
1218         unsigned short length;
1219         unsigned short type;
1220         unsigned short size;
1221         unsigned char *data = *p;
1222         int tlsext_servername = 0;
1223         int renegotiate_seen = 0;
1224
1225         if (data >= (d+n-2))
1226                 goto ri_check;
1227
1228         n2s(data,length);
1229         if (data+length != d+n)
1230                 {
1231                 *al = SSL_AD_DECODE_ERROR;
1232                 return 0;
1233                 }
1234
1235         while(data <= (d+n-4))
1236                 {
1237                 n2s(data,type);
1238                 n2s(data,size);
1239
1240                 if (data+size > (d+n))
1241                         goto ri_check;
1242
1243                 if (s->tlsext_debug_cb)
1244                         s->tlsext_debug_cb(s, 1, type, data, size,
1245                                                 s->tlsext_debug_arg);
1246
1247                 if (type == TLSEXT_TYPE_server_name)
1248                         {
1249                         if (s->tlsext_hostname == NULL || size > 0)
1250                                 {
1251                                 *al = TLS1_AD_UNRECOGNIZED_NAME;
1252                                 return 0;
1253                                 }
1254                         tlsext_servername = 1;   
1255                         }
1256
1257 #ifndef OPENSSL_NO_EC
1258                 else if (type == TLSEXT_TYPE_ec_point_formats &&
1259                      s->version != DTLS1_VERSION)
1260                         {
1261                         unsigned char *sdata = data;
1262                         int ecpointformatlist_length = *(sdata++);
1263
1264                         if (ecpointformatlist_length != size - 1)
1265                                 {
1266                                 *al = TLS1_AD_DECODE_ERROR;
1267                                 return 0;
1268                                 }
1269                         s->session->tlsext_ecpointformatlist_length = 0;
1270                         if (s->session->tlsext_ecpointformatlist != NULL) OPENSSL_free(s->session->tlsext_ecpointformatlist);
1271                         if ((s->session->tlsext_ecpointformatlist = OPENSSL_malloc(ecpointformatlist_length)) == NULL)
1272                                 {
1273                                 *al = TLS1_AD_INTERNAL_ERROR;
1274                                 return 0;
1275                                 }
1276                         s->session->tlsext_ecpointformatlist_length = ecpointformatlist_length;
1277                         memcpy(s->session->tlsext_ecpointformatlist, sdata, ecpointformatlist_length);
1278 #if 0
1279                         fprintf(stderr,"ssl_parse_serverhello_tlsext s->session->tlsext_ecpointformatlist ");
1280                         sdata = s->session->tlsext_ecpointformatlist;
1281                         for (i = 0; i < s->session->tlsext_ecpointformatlist_length; i++)
1282                                 fprintf(stderr,"%i ",*(sdata++));
1283                         fprintf(stderr,"\n");
1284 #endif
1285                         }
1286 #endif /* OPENSSL_NO_EC */
1287
1288                 else if (type == TLSEXT_TYPE_session_ticket)
1289                         {
1290                         if (s->tls_session_ticket_ext_cb &&
1291                             !s->tls_session_ticket_ext_cb(s, data, size, s->tls_session_ticket_ext_cb_arg))
1292                                 {
1293                                 *al = TLS1_AD_INTERNAL_ERROR;
1294                                 return 0;
1295                                 }
1296                         if ((SSL_get_options(s) & SSL_OP_NO_TICKET)
1297                                 || (size > 0))
1298                                 {
1299                                 *al = TLS1_AD_UNSUPPORTED_EXTENSION;
1300                                 return 0;
1301                                 }
1302                         s->tlsext_ticket_expected = 1;
1303                         }
1304 #ifdef TLSEXT_TYPE_opaque_prf_input
1305                 else if (type == TLSEXT_TYPE_opaque_prf_input &&
1306                      s->version != DTLS1_VERSION)
1307                         {
1308                         unsigned char *sdata = data;
1309
1310                         if (size < 2)
1311                                 {
1312                                 *al = SSL_AD_DECODE_ERROR;
1313                                 return 0;
1314                                 }
1315                         n2s(sdata, s->s3->server_opaque_prf_input_len);
1316                         if (s->s3->server_opaque_prf_input_len != size - 2)
1317                                 {
1318                                 *al = SSL_AD_DECODE_ERROR;
1319                                 return 0;
1320                                 }
1321                         
1322                         if (s->s3->server_opaque_prf_input != NULL) /* shouldn't really happen */
1323                                 OPENSSL_free(s->s3->server_opaque_prf_input);
1324                         if (s->s3->server_opaque_prf_input_len == 0)
1325                                 s->s3->server_opaque_prf_input = OPENSSL_malloc(1); /* dummy byte just to get non-NULL */
1326                         else
1327                                 s->s3->server_opaque_prf_input = BUF_memdup(sdata, s->s3->server_opaque_prf_input_len);
1328
1329                         if (s->s3->server_opaque_prf_input == NULL)
1330                                 {
1331                                 *al = TLS1_AD_INTERNAL_ERROR;
1332                                 return 0;
1333                                 }
1334                         }
1335 #endif
1336                 else if (type == TLSEXT_TYPE_status_request &&
1337                          s->version != DTLS1_VERSION)
1338                         {
1339                         /* MUST be empty and only sent if we've requested
1340                          * a status request message.
1341                          */ 
1342                         if ((s->tlsext_status_type == -1) || (size > 0))
1343                                 {
1344                                 *al = TLS1_AD_UNSUPPORTED_EXTENSION;
1345                                 return 0;
1346                                 }
1347                         /* Set flag to expect CertificateStatus message */
1348                         s->tlsext_status_expected = 1;
1349                         }
1350 #ifndef OPENSSL_NO_NEXTPROTONEG
1351                 else if (type == TLSEXT_TYPE_next_proto_neg)
1352                         {
1353                         unsigned char *selected;
1354                         unsigned char selected_len;
1355
1356                         /* We must have requested it. */
1357                         if ((s->ctx->next_proto_select_cb == NULL))
1358                                 {
1359                                 *al = TLS1_AD_UNSUPPORTED_EXTENSION;
1360                                 return 0;
1361                                 }
1362                         /* The data must be valid */
1363                         if (!ssl_next_proto_validate(data, size))
1364                                 {
1365                                 *al = TLS1_AD_DECODE_ERROR;
1366                                 return 0;
1367                                 }
1368                         if (s->ctx->next_proto_select_cb(s, &selected, &selected_len, data, size, s->ctx->next_proto_select_cb_arg) != SSL_TLSEXT_ERR_OK)
1369                                 {
1370                                 *al = TLS1_AD_INTERNAL_ERROR;
1371                                 return 0;
1372                                 }
1373                         s->next_proto_negotiated = OPENSSL_malloc(selected_len);
1374                         if (!s->next_proto_negotiated)
1375                                 {
1376                                 *al = TLS1_AD_INTERNAL_ERROR;
1377                                 return 0;
1378                                 }
1379                         memcpy(s->next_proto_negotiated, selected, selected_len);
1380                         s->next_proto_negotiated_len = selected_len;
1381                         }
1382 #endif
1383                 else if (type == TLSEXT_TYPE_renegotiate)
1384                         {
1385                         if(!ssl_parse_serverhello_renegotiate_ext(s, data, size, al))
1386                                 return 0;
1387                         renegotiate_seen = 1;
1388                         }
1389                 data+=size;             
1390                 }
1391
1392         if (data != d+n)
1393                 {
1394                 *al = SSL_AD_DECODE_ERROR;
1395                 return 0;
1396                 }
1397
1398         if (!s->hit && tlsext_servername == 1)
1399                 {
1400                 if (s->tlsext_hostname)
1401                         {
1402                         if (s->session->tlsext_hostname == NULL)
1403                                 {
1404                                 s->session->tlsext_hostname = BUF_strdup(s->tlsext_hostname);   
1405                                 if (!s->session->tlsext_hostname)
1406                                         {
1407                                         *al = SSL_AD_UNRECOGNIZED_NAME;
1408                                         return 0;
1409                                         }
1410                                 }
1411                         else 
1412                                 {
1413                                 *al = SSL_AD_DECODE_ERROR;
1414                                 return 0;
1415                                 }
1416                         }
1417                 }
1418
1419         *p = data;
1420
1421         ri_check:
1422
1423         /* Determine if we need to see RI. Strictly speaking if we want to
1424          * avoid an attack we should *always* see RI even on initial server
1425          * hello because the client doesn't see any renegotiation during an
1426          * attack. However this would mean we could not connect to any server
1427          * which doesn't support RI so for the immediate future tolerate RI
1428          * absence on initial connect only.
1429          */
1430         if (!renegotiate_seen
1431                 && !(s->options & SSL_OP_LEGACY_SERVER_CONNECT)
1432                 && !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1433                 {
1434                 *al = SSL_AD_HANDSHAKE_FAILURE;
1435                 SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_TLSEXT,
1436                                 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
1437                 return 0;
1438                 }
1439
1440         return 1;
1441         }
1442
1443
1444 int ssl_prepare_clienthello_tlsext(SSL *s)
1445         {
1446 #ifndef OPENSSL_NO_EC
1447         /* If we are client and using an elliptic curve cryptography cipher suite, send the point formats 
1448          * and elliptic curves we support.
1449          */
1450         int using_ecc = 0;
1451         int i;
1452         unsigned char *j;
1453         unsigned long alg_k, alg_a;
1454         STACK_OF(SSL_CIPHER) *cipher_stack = SSL_get_ciphers(s);
1455
1456         for (i = 0; i < sk_SSL_CIPHER_num(cipher_stack); i++)
1457                 {
1458                 SSL_CIPHER *c = sk_SSL_CIPHER_value(cipher_stack, i);
1459
1460                 alg_k = c->algorithm_mkey;
1461                 alg_a = c->algorithm_auth;
1462                 if ((alg_k & (SSL_kEECDH|SSL_kECDHr|SSL_kECDHe) || (alg_a & SSL_aECDSA)))
1463                         {
1464                         using_ecc = 1;
1465                         break;
1466                         }
1467                 }
1468         using_ecc = using_ecc && (s->version >= TLS1_VERSION);
1469         if (using_ecc)
1470                 {
1471                 if (s->tlsext_ecpointformatlist != NULL) OPENSSL_free(s->tlsext_ecpointformatlist);
1472                 if ((s->tlsext_ecpointformatlist = OPENSSL_malloc(3)) == NULL)
1473                         {
1474                         SSLerr(SSL_F_SSL_PREPARE_CLIENTHELLO_TLSEXT,ERR_R_MALLOC_FAILURE);
1475                         return -1;
1476                         }
1477                 s->tlsext_ecpointformatlist_length = 3;
1478                 s->tlsext_ecpointformatlist[0] = TLSEXT_ECPOINTFORMAT_uncompressed;
1479                 s->tlsext_ecpointformatlist[1] = TLSEXT_ECPOINTFORMAT_ansiX962_compressed_prime;
1480                 s->tlsext_ecpointformatlist[2] = TLSEXT_ECPOINTFORMAT_ansiX962_compressed_char2;
1481
1482                 /* we support all named elliptic curves in draft-ietf-tls-ecc-12 */
1483                 if (s->tlsext_ellipticcurvelist != NULL) OPENSSL_free(s->tlsext_ellipticcurvelist);
1484                 s->tlsext_ellipticcurvelist_length = sizeof(nid_list)/sizeof(nid_list[0]) * 2;
1485                 if ((s->tlsext_ellipticcurvelist = OPENSSL_malloc(s->tlsext_ellipticcurvelist_length)) == NULL)
1486                         {
1487                         s->tlsext_ellipticcurvelist_length = 0;
1488                         SSLerr(SSL_F_SSL_PREPARE_CLIENTHELLO_TLSEXT,ERR_R_MALLOC_FAILURE);
1489                         return -1;
1490                         }
1491                 for (i = 1, j = s->tlsext_ellipticcurvelist; (unsigned int)i <=
1492                                 sizeof(nid_list)/sizeof(nid_list[0]); i++)
1493                         s2n(i,j);
1494                 }
1495 #endif /* OPENSSL_NO_EC */
1496
1497 #ifdef TLSEXT_TYPE_opaque_prf_input
1498         {
1499                 int r = 1;
1500         
1501                 if (s->ctx->tlsext_opaque_prf_input_callback != 0)
1502                         {
1503                         r = s->ctx->tlsext_opaque_prf_input_callback(s, NULL, 0, s->ctx->tlsext_opaque_prf_input_callback_arg);
1504                         if (!r)
1505                                 return -1;
1506                         }
1507
1508                 if (s->tlsext_opaque_prf_input != NULL)
1509                         {
1510                         if (s->s3->client_opaque_prf_input != NULL) /* shouldn't really happen */
1511                                 OPENSSL_free(s->s3->client_opaque_prf_input);
1512
1513                         if (s->tlsext_opaque_prf_input_len == 0)
1514                                 s->s3->client_opaque_prf_input = OPENSSL_malloc(1); /* dummy byte just to get non-NULL */
1515                         else
1516                                 s->s3->client_opaque_prf_input = BUF_memdup(s->tlsext_opaque_prf_input, s->tlsext_opaque_prf_input_len);
1517                         if (s->s3->client_opaque_prf_input == NULL)
1518                                 {
1519                                 SSLerr(SSL_F_SSL_PREPARE_CLIENTHELLO_TLSEXT,ERR_R_MALLOC_FAILURE);
1520                                 return -1;
1521                                 }
1522                         s->s3->client_opaque_prf_input_len = s->tlsext_opaque_prf_input_len;
1523                         }
1524
1525                 if (r == 2)
1526                         /* at callback's request, insist on receiving an appropriate server opaque PRF input */
1527                         s->s3->server_opaque_prf_input_len = s->tlsext_opaque_prf_input_len;
1528         }
1529 #endif
1530
1531         return 1;
1532         }
1533
1534 int ssl_prepare_serverhello_tlsext(SSL *s)
1535         {
1536 #ifndef OPENSSL_NO_EC
1537         /* If we are server and using an ECC cipher suite, send the point formats we support 
1538          * if the client sent us an ECPointsFormat extension.  Note that the server is not
1539          * supposed to send an EllipticCurves extension.
1540          */
1541
1542         unsigned long alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
1543         unsigned long alg_a = s->s3->tmp.new_cipher->algorithm_auth;
1544         int using_ecc = (alg_k & (SSL_kEECDH|SSL_kECDHr|SSL_kECDHe)) || (alg_a & SSL_aECDSA);
1545         using_ecc = using_ecc && (s->session->tlsext_ecpointformatlist != NULL);
1546         
1547         if (using_ecc)
1548                 {
1549                 if (s->tlsext_ecpointformatlist != NULL) OPENSSL_free(s->tlsext_ecpointformatlist);
1550                 if ((s->tlsext_ecpointformatlist = OPENSSL_malloc(3)) == NULL)
1551                         {
1552                         SSLerr(SSL_F_SSL_PREPARE_SERVERHELLO_TLSEXT,ERR_R_MALLOC_FAILURE);
1553                         return -1;
1554                         }
1555                 s->tlsext_ecpointformatlist_length = 3;
1556                 s->tlsext_ecpointformatlist[0] = TLSEXT_ECPOINTFORMAT_uncompressed;
1557                 s->tlsext_ecpointformatlist[1] = TLSEXT_ECPOINTFORMAT_ansiX962_compressed_prime;
1558                 s->tlsext_ecpointformatlist[2] = TLSEXT_ECPOINTFORMAT_ansiX962_compressed_char2;
1559                 }
1560 #endif /* OPENSSL_NO_EC */
1561
1562         return 1;
1563         }
1564
1565 int ssl_check_clienthello_tlsext(SSL *s)
1566         {
1567         int ret=SSL_TLSEXT_ERR_NOACK;
1568         int al = SSL_AD_UNRECOGNIZED_NAME;
1569
1570 #ifndef OPENSSL_NO_EC
1571         /* The handling of the ECPointFormats extension is done elsewhere, namely in 
1572          * ssl3_choose_cipher in s3_lib.c.
1573          */
1574         /* The handling of the EllipticCurves extension is done elsewhere, namely in 
1575          * ssl3_choose_cipher in s3_lib.c.
1576          */
1577 #endif
1578
1579         if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0) 
1580                 ret = s->ctx->tlsext_servername_callback(s, &al, s->ctx->tlsext_servername_arg);
1581         else if (s->initial_ctx != NULL && s->initial_ctx->tlsext_servername_callback != 0)             
1582                 ret = s->initial_ctx->tlsext_servername_callback(s, &al, s->initial_ctx->tlsext_servername_arg);
1583
1584         /* If status request then ask callback what to do.
1585          * Note: this must be called after servername callbacks in case 
1586          * the certificate has changed.
1587          */
1588         if ((s->tlsext_status_type != -1) && s->ctx && s->ctx->tlsext_status_cb)
1589                 {
1590                 int r;
1591                 r = s->ctx->tlsext_status_cb(s, s->ctx->tlsext_status_arg);
1592                 switch (r)
1593                         {
1594                         /* We don't want to send a status request response */
1595                         case SSL_TLSEXT_ERR_NOACK:
1596                                 s->tlsext_status_expected = 0;
1597                                 break;
1598                         /* status request response should be sent */
1599                         case SSL_TLSEXT_ERR_OK:
1600                                 if (s->tlsext_ocsp_resp)
1601                                         s->tlsext_status_expected = 1;
1602                                 else
1603                                         s->tlsext_status_expected = 0;
1604                                 break;
1605                         /* something bad happened */
1606                         case SSL_TLSEXT_ERR_ALERT_FATAL:
1607                                 ret = SSL_TLSEXT_ERR_ALERT_FATAL;
1608                                 al = SSL_AD_INTERNAL_ERROR;
1609                                 goto err;
1610                         }
1611                 }
1612         else
1613                 s->tlsext_status_expected = 0;
1614
1615 #ifdef TLSEXT_TYPE_opaque_prf_input
1616         {
1617                 /* This sort of belongs into ssl_prepare_serverhello_tlsext(),
1618                  * but we might be sending an alert in response to the client hello,
1619                  * so this has to happen here in ssl_check_clienthello_tlsext(). */
1620
1621                 int r = 1;
1622         
1623                 if (s->ctx->tlsext_opaque_prf_input_callback != 0)
1624                         {
1625                         r = s->ctx->tlsext_opaque_prf_input_callback(s, NULL, 0, s->ctx->tlsext_opaque_prf_input_callback_arg);
1626                         if (!r)
1627                                 {
1628                                 ret = SSL_TLSEXT_ERR_ALERT_FATAL;
1629                                 al = SSL_AD_INTERNAL_ERROR;
1630                                 goto err;
1631                                 }
1632                         }
1633
1634                 if (s->s3->server_opaque_prf_input != NULL) /* shouldn't really happen */
1635                         OPENSSL_free(s->s3->server_opaque_prf_input);
1636                 s->s3->server_opaque_prf_input = NULL;
1637
1638                 if (s->tlsext_opaque_prf_input != NULL)
1639                         {
1640                         if (s->s3->client_opaque_prf_input != NULL &&
1641                                 s->s3->client_opaque_prf_input_len == s->tlsext_opaque_prf_input_len)
1642                                 {
1643                                 /* can only use this extension if we have a server opaque PRF input
1644                                  * of the same length as the client opaque PRF input! */
1645
1646                                 if (s->tlsext_opaque_prf_input_len == 0)
1647                                         s->s3->server_opaque_prf_input = OPENSSL_malloc(1); /* dummy byte just to get non-NULL */
1648                                 else
1649                                         s->s3->server_opaque_prf_input = BUF_memdup(s->tlsext_opaque_prf_input, s->tlsext_opaque_prf_input_len);
1650                                 if (s->s3->server_opaque_prf_input == NULL)
1651                                         {
1652                                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
1653                                         al = SSL_AD_INTERNAL_ERROR;
1654                                         goto err;
1655                                         }
1656                                 s->s3->server_opaque_prf_input_len = s->tlsext_opaque_prf_input_len;
1657                                 }
1658                         }
1659
1660                 if (r == 2 && s->s3->server_opaque_prf_input == NULL)
1661                         {
1662                         /* The callback wants to enforce use of the extension,
1663                          * but we can't do that with the client opaque PRF input;
1664                          * abort the handshake.
1665                          */
1666                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
1667                         al = SSL_AD_HANDSHAKE_FAILURE;
1668                         }
1669         }
1670
1671 #endif
1672  err:
1673         switch (ret)
1674                 {
1675                 case SSL_TLSEXT_ERR_ALERT_FATAL:
1676                         ssl3_send_alert(s,SSL3_AL_FATAL,al); 
1677                         return -1;
1678
1679                 case SSL_TLSEXT_ERR_ALERT_WARNING:
1680                         ssl3_send_alert(s,SSL3_AL_WARNING,al);
1681                         return 1; 
1682                                         
1683                 case SSL_TLSEXT_ERR_NOACK:
1684                         s->servername_done=0;
1685                         default:
1686                 return 1;
1687                 }
1688         }
1689
1690 int ssl_check_serverhello_tlsext(SSL *s)
1691         {
1692         int ret=SSL_TLSEXT_ERR_NOACK;
1693         int al = SSL_AD_UNRECOGNIZED_NAME;
1694
1695 #ifndef OPENSSL_NO_EC
1696         /* If we are client and using an elliptic curve cryptography cipher
1697          * suite, then if server returns an EC point formats lists extension
1698          * it must contain uncompressed.
1699          */
1700         unsigned long alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
1701         unsigned long alg_a = s->s3->tmp.new_cipher->algorithm_auth;
1702         if ((s->tlsext_ecpointformatlist != NULL) && (s->tlsext_ecpointformatlist_length > 0) && 
1703             (s->session->tlsext_ecpointformatlist != NULL) && (s->session->tlsext_ecpointformatlist_length > 0) && 
1704             ((alg_k & (SSL_kEECDH|SSL_kECDHr|SSL_kECDHe)) || (alg_a & SSL_aECDSA)))
1705                 {
1706                 /* we are using an ECC cipher */
1707                 size_t i;
1708                 unsigned char *list;
1709                 int found_uncompressed = 0;
1710                 list = s->session->tlsext_ecpointformatlist;
1711                 for (i = 0; i < s->session->tlsext_ecpointformatlist_length; i++)
1712                         {
1713                         if (*(list++) == TLSEXT_ECPOINTFORMAT_uncompressed)
1714                                 {
1715                                 found_uncompressed = 1;
1716                                 break;
1717                                 }
1718                         }
1719                 if (!found_uncompressed)
1720                         {
1721                         SSLerr(SSL_F_SSL_CHECK_SERVERHELLO_TLSEXT,SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST);
1722                         return -1;
1723                         }
1724                 }
1725         ret = SSL_TLSEXT_ERR_OK;
1726 #endif /* OPENSSL_NO_EC */
1727
1728         if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0) 
1729                 ret = s->ctx->tlsext_servername_callback(s, &al, s->ctx->tlsext_servername_arg);
1730         else if (s->initial_ctx != NULL && s->initial_ctx->tlsext_servername_callback != 0)             
1731                 ret = s->initial_ctx->tlsext_servername_callback(s, &al, s->initial_ctx->tlsext_servername_arg);
1732
1733 #ifdef TLSEXT_TYPE_opaque_prf_input
1734         if (s->s3->server_opaque_prf_input_len > 0)
1735                 {
1736                 /* This case may indicate that we, as a client, want to insist on using opaque PRF inputs.
1737                  * So first verify that we really have a value from the server too. */
1738
1739                 if (s->s3->server_opaque_prf_input == NULL)
1740                         {
1741                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
1742                         al = SSL_AD_HANDSHAKE_FAILURE;
1743                         }
1744                 
1745                 /* Anytime the server *has* sent an opaque PRF input, we need to check
1746                  * that we have a client opaque PRF input of the same size. */
1747                 if (s->s3->client_opaque_prf_input == NULL ||
1748                     s->s3->client_opaque_prf_input_len != s->s3->server_opaque_prf_input_len)
1749                         {
1750                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
1751                         al = SSL_AD_ILLEGAL_PARAMETER;
1752                         }
1753                 }
1754 #endif
1755
1756         /* If we've requested certificate status and we wont get one
1757          * tell the callback
1758          */
1759         if ((s->tlsext_status_type != -1) && !(s->tlsext_status_expected)
1760                         && s->ctx && s->ctx->tlsext_status_cb)
1761                 {
1762                 int r;
1763                 /* Set resp to NULL, resplen to -1 so callback knows
1764                  * there is no response.
1765                  */
1766                 if (s->tlsext_ocsp_resp)
1767                         {
1768                         OPENSSL_free(s->tlsext_ocsp_resp);
1769                         s->tlsext_ocsp_resp = NULL;
1770                         }
1771                 s->tlsext_ocsp_resplen = -1;
1772                 r = s->ctx->tlsext_status_cb(s, s->ctx->tlsext_status_arg);
1773                 if (r == 0)
1774                         {
1775                         al = SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE;
1776                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
1777                         }
1778                 if (r < 0)
1779                         {
1780                         al = SSL_AD_INTERNAL_ERROR;
1781                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
1782                         }
1783                 }
1784
1785         switch (ret)
1786                 {
1787                 case SSL_TLSEXT_ERR_ALERT_FATAL:
1788                         ssl3_send_alert(s,SSL3_AL_FATAL,al); 
1789                         return -1;
1790
1791                 case SSL_TLSEXT_ERR_ALERT_WARNING:
1792                         ssl3_send_alert(s,SSL3_AL_WARNING,al);
1793                         return 1; 
1794                                         
1795                 case SSL_TLSEXT_ERR_NOACK:
1796                         s->servername_done=0;
1797                         default:
1798                 return 1;
1799                 }
1800         }
1801
1802 /* Since the server cache lookup is done early on in the processing of client
1803  * hello and other operations depend on the result we need to handle any TLS
1804  * session ticket extension at the same time.
1805  */
1806
1807 int tls1_process_ticket(SSL *s, unsigned char *session_id, int len,
1808                                 const unsigned char *limit, SSL_SESSION **ret)
1809         {
1810         /* Point after session ID in client hello */
1811         const unsigned char *p = session_id + len;
1812         unsigned short i;
1813
1814         /* If tickets disabled behave as if no ticket present
1815          * to permit stateful resumption.
1816          */
1817         if (SSL_get_options(s) & SSL_OP_NO_TICKET)
1818                 return 1;
1819
1820         if ((s->version <= SSL3_VERSION) || !limit)
1821                 return 1;
1822         if (p >= limit)
1823                 return -1;
1824         /* Skip past DTLS cookie */
1825         if (s->version == DTLS1_VERSION || s->version == DTLS1_BAD_VER)
1826                 {
1827                 i = *(p++);
1828                 p+= i;
1829                 if (p >= limit)
1830                         return -1;
1831                 }
1832         /* Skip past cipher list */
1833         n2s(p, i);
1834         p+= i;
1835         if (p >= limit)
1836                 return -1;
1837         /* Skip past compression algorithm list */
1838         i = *(p++);
1839         p += i;
1840         if (p > limit)
1841                 return -1;
1842         /* Now at start of extensions */
1843         if ((p + 2) >= limit)
1844                 return 1;
1845         n2s(p, i);
1846         while ((p + 4) <= limit)
1847                 {
1848                 unsigned short type, size;
1849                 n2s(p, type);
1850                 n2s(p, size);
1851                 if (p + size > limit)
1852                         return 1;
1853                 if (type == TLSEXT_TYPE_session_ticket)
1854                         {
1855                         /* If tickets disabled indicate cache miss which will
1856                          * trigger a full handshake
1857                          */
1858                         if (SSL_get_options(s) & SSL_OP_NO_TICKET)
1859                                 return 1;
1860                         /* If zero length note client will accept a ticket
1861                          * and indicate cache miss to trigger full handshake
1862                          */
1863                         if (size == 0)
1864                                 {
1865                                 s->tlsext_ticket_expected = 1;
1866                                 return 0;       /* Cache miss */
1867                                 }
1868                         if (s->tls_session_secret_cb)
1869                                 {
1870                                 /* Indicate cache miss here and instead of
1871                                  * generating the session from ticket now,
1872                                  * trigger abbreviated handshake based on
1873                                  * external mechanism to calculate the master
1874                                  * secret later. */
1875                                 return 0;
1876                                 }
1877                         return tls_decrypt_ticket(s, p, size, session_id, len,
1878                                                                         ret);
1879                         }
1880                 p += size;
1881                 }
1882         return 1;
1883         }
1884
1885 static int tls_decrypt_ticket(SSL *s, const unsigned char *etick, int eticklen,
1886                                 const unsigned char *sess_id, int sesslen,
1887                                 SSL_SESSION **psess)
1888         {
1889         SSL_SESSION *sess;
1890         unsigned char *sdec;
1891         const unsigned char *p;
1892         int slen, mlen, renew_ticket = 0;
1893         unsigned char tick_hmac[EVP_MAX_MD_SIZE];
1894         HMAC_CTX hctx;
1895         EVP_CIPHER_CTX ctx;
1896         SSL_CTX *tctx = s->initial_ctx;
1897         /* Need at least keyname + iv + some encrypted data */
1898         if (eticklen < 48)
1899                 goto tickerr;
1900         /* Initialize session ticket encryption and HMAC contexts */
1901         HMAC_CTX_init(&hctx);
1902         EVP_CIPHER_CTX_init(&ctx);
1903         if (tctx->tlsext_ticket_key_cb)
1904                 {
1905                 unsigned char *nctick = (unsigned char *)etick;
1906                 int rv = tctx->tlsext_ticket_key_cb(s, nctick, nctick + 16,
1907                                                         &ctx, &hctx, 0);
1908                 if (rv < 0)
1909                         return -1;
1910                 if (rv == 0)
1911                         goto tickerr;
1912                 if (rv == 2)
1913                         renew_ticket = 1;
1914                 }
1915         else
1916                 {
1917                 /* Check key name matches */
1918                 if (memcmp(etick, tctx->tlsext_tick_key_name, 16))
1919                         goto tickerr;
1920                 HMAC_Init_ex(&hctx, tctx->tlsext_tick_hmac_key, 16,
1921                                         tlsext_tick_md(), NULL);
1922                 EVP_DecryptInit_ex(&ctx, EVP_aes_128_cbc(), NULL,
1923                                 tctx->tlsext_tick_aes_key, etick + 16);
1924                 }
1925         /* Attempt to process session ticket, first conduct sanity and
1926          * integrity checks on ticket.
1927          */
1928         mlen = HMAC_size(&hctx);
1929         if (mlen < 0)
1930                 {
1931                 EVP_CIPHER_CTX_cleanup(&ctx);
1932                 return -1;
1933                 }
1934         eticklen -= mlen;
1935         /* Check HMAC of encrypted ticket */
1936         HMAC_Update(&hctx, etick, eticklen);
1937         HMAC_Final(&hctx, tick_hmac, NULL);
1938         HMAC_CTX_cleanup(&hctx);
1939         if (memcmp(tick_hmac, etick + eticklen, mlen))
1940                 goto tickerr;
1941         /* Attempt to decrypt session data */
1942         /* Move p after IV to start of encrypted ticket, update length */
1943         p = etick + 16 + EVP_CIPHER_CTX_iv_length(&ctx);
1944         eticklen -= 16 + EVP_CIPHER_CTX_iv_length(&ctx);
1945         sdec = OPENSSL_malloc(eticklen);
1946         if (!sdec)
1947                 {
1948                 EVP_CIPHER_CTX_cleanup(&ctx);
1949                 return -1;
1950                 }
1951         EVP_DecryptUpdate(&ctx, sdec, &slen, p, eticklen);
1952         if (EVP_DecryptFinal(&ctx, sdec + slen, &mlen) <= 0)
1953                 goto tickerr;
1954         slen += mlen;
1955         EVP_CIPHER_CTX_cleanup(&ctx);
1956         p = sdec;
1957                 
1958         sess = d2i_SSL_SESSION(NULL, &p, slen);
1959         OPENSSL_free(sdec);
1960         if (sess)
1961                 {
1962                 /* The session ID if non-empty is used by some clients to
1963                  * detect that the ticket has been accepted. So we copy it to
1964                  * the session structure. If it is empty set length to zero
1965                  * as required by standard.
1966                  */
1967                 if (sesslen)
1968                         memcpy(sess->session_id, sess_id, sesslen);
1969                 sess->session_id_length = sesslen;
1970                 *psess = sess;
1971                 s->tlsext_ticket_expected = renew_ticket;
1972                 return 1;
1973                 }
1974         /* If session decrypt failure indicate a cache miss and set state to
1975          * send a new ticket
1976          */
1977         tickerr:        
1978         s->tlsext_ticket_expected = 1;
1979         return 0;
1980         }
1981
1982 /* Tables to translate from NIDs to TLS v1.2 ids */
1983
1984 typedef struct 
1985         {
1986         int nid;
1987         int id;
1988         } tls12_lookup;
1989
1990 static tls12_lookup tls12_md[] = {
1991 #ifndef OPENSSL_NO_MD5
1992         {NID_md5, TLSEXT_hash_md5},
1993 #endif
1994 #ifndef OPENSSL_NO_SHA
1995         {NID_sha1, TLSEXT_hash_sha1},
1996 #endif
1997 #ifndef OPENSSL_NO_SHA256
1998         {NID_sha224, TLSEXT_hash_sha224},
1999         {NID_sha256, TLSEXT_hash_sha256},
2000 #endif
2001 #ifndef OPENSSL_NO_SHA512
2002         {NID_sha384, TLSEXT_hash_sha384},
2003         {NID_sha512, TLSEXT_hash_sha512}
2004 #endif
2005 };
2006
2007 static tls12_lookup tls12_sig[] = {
2008 #ifndef OPENSSL_NO_RSA
2009         {EVP_PKEY_RSA, TLSEXT_signature_rsa},
2010 #endif
2011 #ifndef OPENSSL_NO_RSA
2012         {EVP_PKEY_DSA, TLSEXT_signature_dsa},
2013 #endif
2014 #ifndef OPENSSL_NO_ECDSA
2015         {EVP_PKEY_EC, TLSEXT_signature_ecdsa}
2016 #endif
2017 };
2018
2019 static int tls12_find_id(int nid, tls12_lookup *table, size_t tlen)
2020         {
2021         size_t i;
2022         for (i = 0; i < tlen; i++)
2023                 {
2024                 if (table[i].nid == nid)
2025                         return table[i].id;
2026                 }
2027         return -1;
2028         }
2029 #if 0
2030 static int tls12_find_nid(int id, tls12_lookup *table, size_t tlen)
2031         {
2032         size_t i;
2033         for (i = 0; i < tlen; i++)
2034                 {
2035                 if (table[i].id == id)
2036                         return table[i].nid;
2037                 }
2038         return -1;
2039         }
2040 #endif
2041
2042 int tls12_get_sigandhash(unsigned char *p, const EVP_PKEY *pk, const EVP_MD *md)
2043         {
2044         int sig_id, md_id;
2045         md_id = tls12_find_id(EVP_MD_type(md), tls12_md,
2046                                 sizeof(tls12_md)/sizeof(tls12_lookup));
2047         if (md_id == -1)
2048                 return 0;
2049         sig_id = tls12_get_sigid(pk);
2050         if (sig_id == -1)
2051                 return 0;
2052         p[0] = (unsigned char)md_id;
2053         p[1] = (unsigned char)sig_id;
2054         return 1;
2055         }
2056
2057 int tls12_get_sigid(const EVP_PKEY *pk)
2058         {
2059         return tls12_find_id(pk->type, tls12_sig,
2060                                 sizeof(tls12_sig)/sizeof(tls12_lookup));
2061         }
2062
2063 const EVP_MD *tls12_get_hash(unsigned char hash_alg)
2064         {
2065         switch(hash_alg)
2066                 {
2067 #ifndef OPENSSL_NO_MD5
2068                 case TLSEXT_hash_md5:
2069                 return EVP_md5();
2070 #endif
2071 #ifndef OPENSSL_NO_SHA
2072                 case TLSEXT_hash_sha1:
2073                 return EVP_sha1();
2074 #endif
2075 #ifndef OPENSSL_NO_SHA256
2076                 case TLSEXT_hash_sha224:
2077                 return EVP_sha224();
2078
2079                 case TLSEXT_hash_sha256:
2080                 return EVP_sha256();
2081 #endif
2082 #ifndef OPENSSL_NO_SHA512
2083                 case TLSEXT_hash_sha384:
2084                 return EVP_sha384();
2085
2086                 case TLSEXT_hash_sha512:
2087                 return EVP_sha512();
2088 #endif
2089                 default:
2090                 return NULL;
2091
2092                 }
2093         }
2094
2095 /* Set preferred digest for each key type */
2096
2097 int tls1_process_sigalgs(SSL *s, const unsigned char *data, int dsize)
2098         {
2099         int i, idx;
2100         const EVP_MD *md;
2101         CERT *c = s->cert;
2102         /* Extension ignored for TLS versions below 1.2 */
2103         if (s->version < TLS1_2_VERSION)
2104                 return 1;
2105         /* Should never happen */
2106         if (!c)
2107                 return 0;
2108
2109         c->pkeys[SSL_PKEY_DSA_SIGN].digest = NULL;
2110         c->pkeys[SSL_PKEY_RSA_SIGN].digest = NULL;
2111         c->pkeys[SSL_PKEY_RSA_ENC].digest = NULL;
2112         c->pkeys[SSL_PKEY_ECC].digest = NULL;
2113
2114         for (i = 0; i < dsize; i += 2)
2115                 {
2116                 unsigned char hash_alg = data[i], sig_alg = data[i+1];
2117
2118                 switch(sig_alg)
2119                         {
2120 #ifndef OPENSSL_NO_RSA
2121                         case TLSEXT_signature_rsa:
2122                         idx = SSL_PKEY_RSA_SIGN;
2123                         break;
2124 #endif
2125 #ifndef OPENSSL_NO_DSA
2126                         case TLSEXT_signature_dsa:
2127                         idx = SSL_PKEY_DSA_SIGN;
2128                         break;
2129 #endif
2130 #ifndef OPENSSL_NO_ECDSA
2131                         case TLSEXT_signature_ecdsa:
2132                         idx = SSL_PKEY_ECC;
2133                         break;
2134 #endif
2135                         default:
2136                         continue;
2137                         }
2138
2139                 if (c->pkeys[idx].digest == NULL)
2140                         {
2141                         md = tls12_get_hash(hash_alg);
2142                         if (md)
2143                                 {
2144                                 c->pkeys[idx].digest = md;
2145                                 if (idx == SSL_PKEY_RSA_SIGN)
2146                                         c->pkeys[SSL_PKEY_RSA_ENC].digest = md;
2147                                 }
2148                         }
2149
2150                 }
2151
2152
2153         /* Set any remaining keys to default values. NOTE: if alg is not
2154          * supported it stays as NULL.
2155          */
2156 #ifndef OPENSSL_NO_DSA
2157         if (!c->pkeys[SSL_PKEY_DSA_SIGN].digest)
2158                 c->pkeys[SSL_PKEY_DSA_SIGN].digest = EVP_dss1();
2159 #endif
2160 #ifndef OPENSSL_NO_RSA
2161         if (!c->pkeys[SSL_PKEY_RSA_SIGN].digest)
2162                 {
2163                 c->pkeys[SSL_PKEY_RSA_SIGN].digest = EVP_sha1();
2164                 c->pkeys[SSL_PKEY_RSA_ENC].digest = EVP_sha1();
2165                 }
2166 #endif
2167 #ifndef OPENSSL_NO_ECDSA
2168         if (!c->pkeys[SSL_PKEY_ECC].digest)
2169                 c->pkeys[SSL_PKEY_ECC].digest = EVP_ecdsa();
2170 #endif
2171         return 1;
2172         }
2173
2174 #endif