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 "ssl_locl.h"
 117
 118 const char tls1_version_str[]="TLSv1" OPENSSL_VERSION_PTEXT;
 119
 120 #ifndef OPENSSL_NO_TLSEXT
 121 static int tls_decrypt_ticket(SSL *s, const unsigned char *tick, int ticklen,
 122                                 const unsigned char *sess_id, int sesslen,
 123                                 SSL_SESSION **psess);
 124 #endif
 125
 126 SSL3_ENC_METHOD TLSv1_enc_data={
 127         tls1_enc,
 128         tls1_mac,
 129         tls1_setup_key_block,
 130         tls1_generate_master_secret,
 131         tls1_change_cipher_state,
 132         tls1_final_finish_mac,
 133         TLS1_FINISH_MAC_LENGTH,
 134         tls1_cert_verify_mac,
 135         TLS_MD_CLIENT_FINISH_CONST,TLS_MD_CLIENT_FINISH_CONST_SIZE,
 136         TLS_MD_SERVER_FINISH_CONST,TLS_MD_SERVER_FINISH_CONST_SIZE,
 137         tls1_alert_code,
 138         };
 139
 140 long tls1_default_timeout(void)
 141         {
 142         /* 2 hours, the 24 hours mentioned in the TLSv1 spec
 143          * is way too long for http, the cache would over fill */
 144         return(60*60*2);
 145         }
 146
 147 int tls1_new(SSL *s)
 148         {
 149         if (!ssl3_new(s)) return(0);
 150         s->method->ssl_clear(s);
 151         return(1);
 152         }
 153
 154 void tls1_free(SSL *s)
 155         {
 156         ssl3_free(s);
 157         }
 158
 159 void tls1_clear(SSL *s)
 160         {
 161         ssl3_clear(s);
 162         s->version=TLS1_VERSION;
 163         }
 164
 165 #ifndef OPENSSL_NO_EC
 166 static int nid_list[] =
 167         {
 168                 NID_sect163k1, /* sect163k1 (1) */
 169                 NID_sect163r1, /* sect163r1 (2) */
 170                 NID_sect163r2, /* sect163r2 (3) */
 171                 NID_sect193r1, /* sect193r1 (4) */
 172                 NID_sect193r2, /* sect193r2 (5) */
 173                 NID_sect233k1, /* sect233k1 (6) */
 174                 NID_sect233r1, /* sect233r1 (7) */
 175                 NID_sect239k1, /* sect239k1 (8) */
 176                 NID_sect283k1, /* sect283k1 (9) */
 177                 NID_sect283r1, /* sect283r1 (10) */
 178                 NID_sect409k1, /* sect409k1 (11) */
 179                 NID_sect409r1, /* sect409r1 (12) */
 180                 NID_sect571k1, /* sect571k1 (13) */
 181                 NID_sect571r1, /* sect571r1 (14) */
 182                 NID_secp160k1, /* secp160k1 (15) */
 183                 NID_secp160r1, /* secp160r1 (16) */
 184                 NID_secp160r2, /* secp160r2 (17) */
 185                 NID_secp192k1, /* secp192k1 (18) */
 186                 NID_X9_62_prime192v1, /* secp192r1 (19) */
 187                 NID_secp224k1, /* secp224k1 (20) */
 188                 NID_secp224r1, /* secp224r1 (21) */
 189                 NID_secp256k1, /* secp256k1 (22) */
 190                 NID_X9_62_prime256v1, /* secp256r1 (23) */
 191                 NID_secp384r1, /* secp384r1 (24) */
 192                 NID_secp521r1  /* secp521r1 (25) */
 193         };
 194
 195 int tls1_ec_curve_id2nid(int curve_id)
 196         {
 197         /* ECC curves from draft-ietf-tls-ecc-12.txt (Oct. 17, 2005) */
 198         if ((curve_id < 1) || (curve_id > sizeof(nid_list)/sizeof(nid_list[0]))) return 0;
 199         return nid_list[curve_id-1];
 200         }
 201
 202 int tls1_ec_nid2curve_id(int nid)
 203         {
 204         /* ECC curves from draft-ietf-tls-ecc-12.txt (Oct. 17, 2005) */
 205         switch (nid)
 206                 {
 207         case NID_sect163k1: /* sect163k1 (1) */
 208                 return 1;
 209         case NID_sect163r1: /* sect163r1 (2) */
 210                 return 2;
 211         case NID_sect163r2: /* sect163r2 (3) */
 212                 return 3;
 213         case NID_sect193r1: /* sect193r1 (4) */
 214                 return 4;
 215         case NID_sect193r2: /* sect193r2 (5) */
 216                 return 5;
 217         case NID_sect233k1: /* sect233k1 (6) */
 218                 return 6;
 219         case NID_sect233r1: /* sect233r1 (7) */
 220                 return 7;
 221         case NID_sect239k1: /* sect239k1 (8) */
 222                 return 8;
 223         case NID_sect283k1: /* sect283k1 (9) */
 224                 return 9;
 225         case NID_sect283r1: /* sect283r1 (10) */
 226                 return 10;
 227         case NID_sect409k1: /* sect409k1 (11) */
 228                 return 11;
 229         case NID_sect409r1: /* sect409r1 (12) */
 230                 return 12;
 231         case NID_sect571k1: /* sect571k1 (13) */
 232                 return 13;
 233         case NID_sect571r1: /* sect571r1 (14) */
 234                 return 14;
 235         case NID_secp160k1: /* secp160k1 (15) */
 236                 return 15;
 237         case NID_secp160r1: /* secp160r1 (16) */
 238                 return 16;
 239         case NID_secp160r2: /* secp160r2 (17) */
 240                 return 17;
 241         case NID_secp192k1: /* secp192k1 (18) */
 242                 return 18;
 243         case NID_X9_62_prime192v1: /* secp192r1 (19) */
 244                 return 19;
 245         case NID_secp224k1: /* secp224k1 (20) */
 246                 return 20;
 247         case NID_secp224r1: /* secp224r1 (21) */
 248                 return 21;
 249         case NID_secp256k1: /* secp256k1 (22) */
 250                 return 22;
 251         case NID_X9_62_prime256v1: /* secp256r1 (23) */
 252                 return 23;
 253         case NID_secp384r1: /* secp384r1 (24) */
 254                 return 24;
 255         case NID_secp521r1:  /* secp521r1 (25) */
 256                 return 25;
 257         default:
 258                 return 0;
 259                 }
 260         }
 261 #endif /* OPENSSL_NO_EC */
 262
 263 #ifndef OPENSSL_NO_TLSEXT
 264 unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned char *limit)
 265         {
 266         int extdatalen=0;
 267         unsigned char *ret = p;
 268
 269         ret+=2;
 270
 271         if (ret>=limit) return NULL; /* this really never occurs, but ... */
 272
 273         if (s->tlsext_hostname != NULL)
 274                 {
 275                 /* Add TLS extension servername to the Client Hello message */
 276                 unsigned long size_str;
 277                 long lenmax;
 278
 279                 /* check for enough space.
 280                    4 for the servername type and entension length
 281                    2 for servernamelist length
 282                    1 for the hostname type
 283                    2 for hostname length
 284                    + hostname length
 285                 */
 286
 287                 if ((lenmax = limit - ret - 9) < 0
 288                     || (size_str = strlen(s->tlsext_hostname)) > (unsigned long)lenmax)
 289                         return NULL;
 290
 291                 /* extension type and length */
 292                 s2n(TLSEXT_TYPE_server_name,ret);
 293                 s2n(size_str+5,ret);
 294
 295                 /* length of servername list */
 296                 s2n(size_str+3,ret);
 297
 298                 /* hostname type, length and hostname */
 299                 *(ret++) = (unsigned char) TLSEXT_NAMETYPE_host_name;
 300                 s2n(size_str,ret);
 301                 memcpy(ret, s->tlsext_hostname, size_str);
 302                 ret+=size_str;
 303                 }
 304
 305 #ifndef OPENSSL_NO_EC
 306         if (s->tlsext_ecpointformatlist != NULL)
 307                 {
 308                 /* Add TLS extension ECPointFormats to the ClientHello message */
 309                 long lenmax;
 310
 311                 if ((lenmax = limit - ret - 5) < 0) return NULL;
 312                 if (s->tlsext_ecpointformatlist_length > (unsigned long)lenmax) return NULL;
 313                 if (s->tlsext_ecpointformatlist_length > 255)
 314                         {
 315                         SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
 316                         return NULL;
 317                         }
 318
 319                 s2n(TLSEXT_TYPE_ec_point_formats,ret);
 320                 s2n(s->tlsext_ecpointformatlist_length + 1,ret);
 321                 *(ret++) = (unsigned char) s->tlsext_ecpointformatlist_length;
 322                 memcpy(ret, s->tlsext_ecpointformatlist, s->tlsext_ecpointformatlist_length);
 323                 ret+=s->tlsext_ecpointformatlist_length;
 324                 }
 325         if (s->tlsext_ellipticcurvelist != NULL)
 326                 {
 327                 /* Add TLS extension EllipticCurves to the ClientHello message */
 328                 long lenmax;
 329
 330                 if ((lenmax = limit - ret - 6) < 0) return NULL;
 331                 if (s->tlsext_ellipticcurvelist_length > (unsigned long)lenmax) return NULL;
 332                 if (s->tlsext_ellipticcurvelist_length > 65532)
 333                         {
 334                         SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
 335                         return NULL;
 336                         }
 337
 338                 s2n(TLSEXT_TYPE_elliptic_curves,ret);
 339                 s2n(s->tlsext_ellipticcurvelist_length + 2, ret);
 340
 341                 /* NB: draft-ietf-tls-ecc-12.txt uses a one-byte prefix for
 342                  * elliptic_curve_list, but the examples use two bytes.
 343                  * http://www1.ietf.org/mail-archive/web/tls/current/msg00538.html
 344                  * resolves this to two bytes.
 345                  */
 346                 s2n(s->tlsext_ellipticcurvelist_length, ret);
 347                 memcpy(ret, s->tlsext_ellipticcurvelist, s->tlsext_ellipticcurvelist_length);
 348                 ret+=s->tlsext_ellipticcurvelist_length;
 349                 }
 350 #endif /* OPENSSL_NO_EC */
 351
 352         if (!(SSL_get_options(s) & SSL_OP_NO_TICKET))
 353                 {
 354                 int ticklen;
 355                 if (s->session && s->session->tlsext_tick)
 356                         ticklen = s->session->tlsext_ticklen;
 357                 else
 358                         ticklen = 0;
 359                 /* Check for enough room 2 for extension type, 2 for len
 360                  * rest for ticket
 361                  */
 362                 if ((long)(limit - ret - 4 - ticklen) < 0) return NULL;
 363                 s2n(TLSEXT_TYPE_session_ticket,ret);
 364                 s2n(ticklen,ret);
 365                 if (ticklen)
 366                         {
 367                         memcpy(ret, s->session->tlsext_tick, ticklen);
 368                         ret += ticklen;
 369                         }
 370                 }
 371
 372 #ifdef TLSEXT_TYPE_opaque_prf_input
 373         if (s->s3->client_opaque_prf_input != NULL)
 374                 {
 375                 size_t col = s->s3->client_opaque_prf_input_len;
 376
 377                 if ((long)(limit - ret - 6 - col < 0))
 378                         return NULL;
 379                 if (col > 0xFFFD) /* can't happen */
 380                         return NULL;
 381
 382                 s2n(TLSEXT_TYPE_opaque_prf_input, ret);
 383                 s2n(col + 2, ret);
 384                 s2n(col, ret);
 385                 memcpy(ret, s->s3->client_opaque_prf_input, col);
 386                 ret += col;
 387                 }
 388 #endif
 389
 390         if ((extdatalen = ret-p-2)== 0)
 391                 return p;
 392
 393         s2n(extdatalen,p);
 394         return ret;
 395         }
 396
 397 unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *p, unsigned char *limit)
 398         {
 399         int extdatalen=0;
 400         unsigned char *ret = p;
 401
 402         ret+=2;
 403         if (ret>=limit) return NULL; /* this really never occurs, but ... */
 404
 405         if (!s->hit && s->servername_done == 1 && s->session->tlsext_hostname != NULL)
 406                 {
 407                 if ((long)(limit - ret - 4) < 0) return NULL;
 408
 409                 s2n(TLSEXT_TYPE_server_name,ret);
 410                 s2n(0,ret);
 411                 }
 412 #ifndef OPENSSL_NO_EC
 413         if (s->tlsext_ecpointformatlist != NULL)
 414                 {
 415                 /* Add TLS extension ECPointFormats to the ServerHello message */
 416                 long lenmax;
 417
 418                 if ((lenmax = limit - ret - 5) < 0) return NULL;
 419                 if (s->tlsext_ecpointformatlist_length > (unsigned long)lenmax) return NULL;
 420                 if (s->tlsext_ecpointformatlist_length > 255)
 421                         {
 422                         SSLerr(SSL_F_SSL_ADD_SERVERHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
 423                         return NULL;
 424                         }
 425
 426                 s2n(TLSEXT_TYPE_ec_point_formats,ret);
 427                 s2n(s->tlsext_ecpointformatlist_length + 1,ret);
 428                 *(ret++) = (unsigned char) s->tlsext_ecpointformatlist_length;
 429                 memcpy(ret, s->tlsext_ecpointformatlist, s->tlsext_ecpointformatlist_length);
 430                 ret+=s->tlsext_ecpointformatlist_length;
 431
 432                 }
 433         /* Currently the server should not respond with a SupportedCurves extension */
 434 #endif /* OPENSSL_NO_EC */
 435
 436         if (s->tlsext_ticket_expected
 437                 && !(SSL_get_options(s) & SSL_OP_NO_TICKET))
 438                 {
 439                 if ((long)(limit - ret - 4) < 0) return NULL;
 440                 s2n(TLSEXT_TYPE_session_ticket,ret);
 441                 s2n(0,ret);
 442                 }
 443
 444 #ifdef TLSEXT_TYPE_opaque_prf_input
 445         if (s->s3->server_opaque_prf_input != NULL)
 446                 {
 447                 size_t sol = s->s3->server_opaque_prf_input_len;
 448
 449                 if ((long)(limit - ret - 6 - sol) < 0)
 450                         return NULL;
 451                 if (sol > 0xFFFD) /* can't happen */
 452                         return NULL;
 453
 454                 s2n(TLSEXT_TYPE_opaque_prf_input, ret);
 455                 s2n(sol + 2, ret);
 456                 s2n(sol, ret);
 457                 memcpy(ret, s->s3->server_opaque_prf_input, sol);
 458                 ret += sol;
 459                 }
 460 #endif
 461
 462         if ((extdatalen = ret-p-2)== 0)
 463                 return p;
 464
 465         s2n(extdatalen,p);
 466         return ret;
 467         }
 468
 469 int ssl_parse_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char *d, int n, int *al)
 470         {
 471         unsigned short type;
 472         unsigned short size;
 473         unsigned short len;
 474         unsigned char *data = *p;
 475         s->servername_done = 0;
 476
 477         if (data >= (d+n-2))
 478                 return 1;
 479         n2s(data,len);
 480
 481         if (data > (d+n-len))
 482                 return 1;
 483
 484         while (data <= (d+n-4))
 485                 {
 486                 n2s(data,type);
 487                 n2s(data,size);
 488
 489                 if (data+size > (d+n))
 490                         return 1;
 491
 492                 if (s->tlsext_debug_cb)
 493                         s->tlsext_debug_cb(s, 0, type, data, size,
 494                                                 s->tlsext_debug_arg);
 495 /* The servername extension is treated as follows:
 496
 497    - Only the hostname type is supported with a maximum length of 255.
 498    - The servername is rejected if too long or if it contains zeros,
 499      in which case an fatal alert is generated.
 500    - The servername field is maintained together with the session cache.
 501    - When a session is resumed, the servername call back invoked in order
 502      to allow the application to position itself to the right context.
 503    - The servername is acknowledged if it is new for a session or when
 504      it is identical to a previously used for the same session.
 505      Applications can control the behaviour.  They can at any time
 506      set a 'desirable' servername for a new SSL object. This can be the
 507      case for example with HTTPS when a Host: header field is received and
 508      a renegotiation is requested. In this case, a possible servername
 509      presented in the new client hello is only acknowledged if it matches
 510      the value of the Host: field.
 511    - Applications must  use SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION
 512      if they provide for changing an explicit servername context for the session,
 513      i.e. when the session has been established with a servername extension.
 514    - On session reconnect, the servername extension may be absent.
 515
 516 */
 517
 518                 if (type == TLSEXT_TYPE_server_name)
 519                         {
 520                         unsigned char *sdata;
 521                         int servname_type;
 522                         int dsize;
 523
 524                         if (size < 2)
 525                                 {
 526                                 *al = SSL_AD_DECODE_ERROR;
 527                                 return 0;
 528                                 }
 529                         n2s(data,dsize);
 530                         size -= 2;
 531                         if (dsize > size  )
 532                                 {
 533                                 *al = SSL_AD_DECODE_ERROR;
 534                                 return 0;
 535                                 }
 536
 537                         sdata = data;
 538                         while (dsize > 3)
 539                                 {
 540                                 servname_type = *(sdata++);
 541                                 n2s(sdata,len);
 542                                 dsize -= 3;
 543
 544                                 if (len > dsize)
 545                                         {
 546                                         *al = SSL_AD_DECODE_ERROR;
 547                                         return 0;
 548                                         }
 549                                 if (s->servername_done == 0)
 550                                 switch (servname_type)
 551                                         {
 552                                 case TLSEXT_NAMETYPE_host_name:
 553                                         if (s->session->tlsext_hostname == NULL)
 554                                                 {
 555                                                 if (len > TLSEXT_MAXLEN_host_name ||
 556                                                         ((s->session->tlsext_hostname = OPENSSL_malloc(len+1)) == NULL))
 557                                                         {
 558                                                         *al = TLS1_AD_UNRECOGNIZED_NAME;
 559                                                         return 0;
 560                                                         }
 561                                                 memcpy(s->session->tlsext_hostname, sdata, len);
 562                                                 s->session->tlsext_hostname[len]='\0';
 563                                                 if (strlen(s->session->tlsext_hostname) != len) {
 564                                                         OPENSSL_free(s->session->tlsext_hostname);
 565                                                         *al = TLS1_AD_UNRECOGNIZED_NAME;
 566                                                         return 0;
 567                                                 }
 568                                                 s->servername_done = 1;
 569
 570                                                 }
 571                                         else
 572                                                 s->servername_done = strlen(s->session->tlsext_hostname) == len
 573                                                         && strncmp(s->session->tlsext_hostname, (char *)sdata, len) == 0;
 574
 575                                         break;
 576
 577                                 default:
 578                                         break;
 579                                         }
 580
 581                                 dsize -= len;
 582                                 }
 583                         if (dsize != 0)
 584                                 {
 585                                 *al = SSL_AD_DECODE_ERROR;
 586                                 return 0;
 587                                 }
 588
 589                         }
 590
 591 #ifndef OPENSSL_NO_EC
 592                 else if (type == TLSEXT_TYPE_ec_point_formats)
 593                         {
 594                         unsigned char *sdata = data;
 595                         int ecpointformatlist_length = *(sdata++);
 596
 597                         if (ecpointformatlist_length != size - 1)
 598                                 {
 599                                 *al = TLS1_AD_DECODE_ERROR;
 600                                 return 0;
 601                                 }
 602                         s->session->tlsext_ecpointformatlist_length = 0;
 603                         if (s->session->tlsext_ecpointformatlist != NULL) OPENSSL_free(s->session->tlsext_ecpointformatlist);
 604                         if ((s->session->tlsext_ecpointformatlist = OPENSSL_malloc(ecpointformatlist_length)) == NULL)
 605                                 {
 606                                 *al = TLS1_AD_INTERNAL_ERROR;
 607                                 return 0;
 608                                 }
 609                         s->session->tlsext_ecpointformatlist_length = ecpointformatlist_length;
 610                         memcpy(s->session->tlsext_ecpointformatlist, sdata, ecpointformatlist_length);
 611 #if 0
 612                         fprintf(stderr,"ssl_parse_clienthello_tlsext s->session->tlsext_ecpointformatlist (length=%i) ", s->session->tlsext_ecpointformatlist_length);
 613                         sdata = s->session->tlsext_ecpointformatlist;
 614                         for (i = 0; i < s->session->tlsext_ecpointformatlist_length; i++)
 615                                 fprintf(stderr,"%i ",*(sdata++));
 616                         fprintf(stderr,"\n");
 617 #endif
 618                         }
 619                 else if (type == TLSEXT_TYPE_elliptic_curves)
 620                         {
 621                         unsigned char *sdata = data;
 622                         int ellipticcurvelist_length = (*(sdata++) << 8);
 623                         ellipticcurvelist_length += (*(sdata++));
 624
 625                         if (ellipticcurvelist_length != size - 2)
 626                                 {
 627                                 *al = TLS1_AD_DECODE_ERROR;
 628                                 return 0;
 629                                 }
 630                         s->session->tlsext_ellipticcurvelist_length = 0;
 631                         if (s->session->tlsext_ellipticcurvelist != NULL) OPENSSL_free(s->session->tlsext_ellipticcurvelist);
 632                         if ((s->session->tlsext_ellipticcurvelist = OPENSSL_malloc(ellipticcurvelist_length)) == NULL)
 633                                 {
 634                                 *al = TLS1_AD_INTERNAL_ERROR;
 635                                 return 0;
 636                                 }
 637                         s->session->tlsext_ellipticcurvelist_length = ellipticcurvelist_length;
 638                         memcpy(s->session->tlsext_ellipticcurvelist, sdata, ellipticcurvelist_length);
 639 #if 0
 640                         fprintf(stderr,"ssl_parse_clienthello_tlsext s->session->tlsext_ellipticcurvelist (length=%i) ", s->session->tlsext_ellipticcurvelist_length);
 641                         sdata = s->session->tlsext_ellipticcurvelist;
 642                         for (i = 0; i < s->session->tlsext_ellipticcurvelist_length; i++)
 643                                 fprintf(stderr,"%i ",*(sdata++));
 644                         fprintf(stderr,"\n");
 645 #endif
 646                         }
 647 #endif /* OPENSSL_NO_EC */
 648 #ifdef TLSEXT_TYPE_opaque_prf_input
 649                 else if (type == TLSEXT_TYPE_opaque_prf_input)
 650                         {
 651                         unsigned char *sdata = data;
 652
 653                         if (size < 2)
 654                                 {
 655                                 *al = SSL_AD_DECODE_ERROR;
 656                                 return 0;
 657                                 }
 658                         n2s(sdata, s->s3->client_opaque_prf_input_len);
 659                         if (s->s3->client_opaque_prf_input_len != size - 2)
 660                                 {
 661                                 *al = SSL_AD_DECODE_ERROR;
 662                                 return 0;
 663                                 }
 664
 665                         if (s->s3->client_opaque_prf_input != NULL) /* shouldn't really happen */
 666                                 OPENSSL_free(s->s3->client_opaque_prf_input);
 667
 668                         s->s3->client_opaque_prf_input = BUF_memdup(sdata, s->s3->client_opaque_prf_input_len);
 669                         if (s->s3->client_opaque_prf_input == NULL)
 670                                 {
 671                                 *al = TLS1_AD_INTERNAL_ERROR;
 672                                 return 0;
 673                                 }
 674                         }
 675 #endif
 676
 677                 /* session ticket processed earlier */
 678                 data+=size;
 679                 }
 680
 681         *p = data;
 682         return 1;
 683         }
 684
 685 int ssl_parse_serverhello_tlsext(SSL *s, unsigned char **p, unsigned char *d, int n, int *al)
 686         {
 687         unsigned short type;
 688         unsigned short size;
 689         unsigned short len;
 690         unsigned char *data = *p;
 691
 692         int tlsext_servername = 0;
 693
 694         if (data >= (d+n-2))
 695                 return 1;
 696
 697         n2s(data,len);
 698
 699         while(data <= (d+n-4))
 700                 {
 701                 n2s(data,type);
 702                 n2s(data,size);
 703
 704                 if (data+size > (d+n))
 705                         return 1;
 706
 707                 if (s->tlsext_debug_cb)
 708                         s->tlsext_debug_cb(s, 1, type, data, size,
 709                                                 s->tlsext_debug_arg);
 710
 711                 if (type == TLSEXT_TYPE_server_name)
 712                         {
 713                         if (s->tlsext_hostname == NULL || size > 0)
 714                                 {
 715                                 *al = TLS1_AD_UNRECOGNIZED_NAME;
 716                                 return 0;
 717                                 }
 718                         tlsext_servername = 1;
 719                         }
 720
 721 #ifndef OPENSSL_NO_EC
 722                 else if (type == TLSEXT_TYPE_ec_point_formats)
 723                         {
 724                         unsigned char *sdata = data;
 725                         int ecpointformatlist_length = *(sdata++);
 726
 727                         if (ecpointformatlist_length != size - 1)
 728                                 {
 729                                 *al = TLS1_AD_DECODE_ERROR;
 730                                 return 0;
 731                                 }
 732                         s->session->tlsext_ecpointformatlist_length = 0;
 733                         if (s->session->tlsext_ecpointformatlist != NULL) OPENSSL_free(s->session->tlsext_ecpointformatlist);
 734                         if ((s->session->tlsext_ecpointformatlist = OPENSSL_malloc(ecpointformatlist_length)) == NULL)
 735                                 {
 736                                 *al = TLS1_AD_INTERNAL_ERROR;
 737                                 return 0;
 738                                 }
 739                         s->session->tlsext_ecpointformatlist_length = ecpointformatlist_length;
 740                         memcpy(s->session->tlsext_ecpointformatlist, sdata, ecpointformatlist_length);
 741 #if 0
 742                         fprintf(stderr,"ssl_parse_serverhello_tlsext s->session->tlsext_ecpointformatlist ");
 743                         sdata = s->session->tlsext_ecpointformatlist;
 744                         for (i = 0; i < s->session->tlsext_ecpointformatlist_length; i++)
 745                                 fprintf(stderr,"%i ",*(sdata++));
 746                         fprintf(stderr,"\n");
 747 #endif
 748                         }
 749 #endif /* OPENSSL_NO_EC */
 750
 751                 else if (type == TLSEXT_TYPE_session_ticket)
 752                         {
 753                         if ((SSL_get_options(s) & SSL_OP_NO_TICKET)
 754                                 || (size > 0))
 755                                 {
 756                                 *al = TLS1_AD_UNSUPPORTED_EXTENSION;
 757                                 return 0;
 758                                 }
 759                         s->tlsext_ticket_expected = 1;
 760                         }
 761 #ifdef TLSEXT_TYPE_opaque_prf_input
 762                 else if (type == TLSEXT_TYPE_opaque_prf_input)
 763                         {
 764                         unsigned char *sdata = data;
 765
 766                         if (size < 2)
 767                                 {
 768                                 *al = SSL_AD_DECODE_ERROR;
 769                                 return 0;
 770                                 }
 771                         n2s(sdata, s->s3->server_opaque_prf_input_len);
 772                         if (s->s3->server_opaque_prf_input_len != size - 2)
 773                                 {
 774                                 *al = SSL_AD_DECODE_ERROR;
 775                                 return 0;
 776                                 }
 777
 778                         if (s->s3->server_opaque_prf_input != NULL) /* shouldn't really happen */
 779                                 OPENSSL_free(s->s3->server_opaque_prf_input);
 780                         s->s3->server_opaque_prf_input = BUF_memdup(sdata, s->s3->server_opaque_prf_input_len);
 781
 782                         if (s->s3->server_opaque_prf_input == NULL)
 783                                 {
 784                                 *al = TLS1_AD_INTERNAL_ERROR;
 785                                 return 0;
 786                                 }
 787                         }
 788 #endif
 789
 790                 data+=size;
 791                 }
 792
 793         if (data != d+n)
 794                 {
 795                 *al = SSL_AD_DECODE_ERROR;
 796                 return 0;
 797                 }
 798
 799         if (!s->hit && tlsext_servername == 1)
 800                 {
 801                 if (s->tlsext_hostname)
 802                         {
 803                         if (s->session->tlsext_hostname == NULL)
 804                                 {
 805                                 s->session->tlsext_hostname = BUF_strdup(s->tlsext_hostname);
 806                                 if (!s->session->tlsext_hostname)
 807                                         {
 808                                         *al = SSL_AD_UNRECOGNIZED_NAME;
 809                                         return 0;
 810                                         }
 811                                 }
 812                         else
 813                                 {
 814                                 *al = SSL_AD_DECODE_ERROR;
 815                                 return 0;
 816                                 }
 817                         }
 818                 }
 819
 820         *p = data;
 821         return 1;
 822         }
 823
 824
 825 int ssl_prepare_clienthello_tlsext(SSL *s)
 826         {
 827 #ifndef OPENSSL_NO_EC
 828         /* If we are client and using an elliptic curve cryptography cipher suite, send the point formats
 829          * and elliptic curves we support.
 830          */
 831         int using_ecc = 0;
 832         int i;
 833         unsigned char *j;
 834         unsigned long alg_k, alg_a;
 835         STACK_OF(SSL_CIPHER) *cipher_stack = SSL_get_ciphers(s);
 836
 837         for (i = 0; i < sk_SSL_CIPHER_num(cipher_stack); i++)
 838                 {
 839                 SSL_CIPHER *c = sk_SSL_CIPHER_value(cipher_stack, i);
 840
 841                 alg_k = c->algorithm_mkey;
 842                 alg_a = c->algorithm_auth;
 843                 if ((alg_k & (SSL_kEECDH|SSL_kECDHr|SSL_kECDHe) || (alg_a & SSL_aECDSA)))
 844                         {
 845                         using_ecc = 1;
 846                         break;
 847                         }
 848                 }
 849         using_ecc = using_ecc && (s->version == TLS1_VERSION);
 850         if (using_ecc)
 851                 {
 852                 if (s->tlsext_ecpointformatlist != NULL) OPENSSL_free(s->tlsext_ecpointformatlist);
 853                 if ((s->tlsext_ecpointformatlist = OPENSSL_malloc(3)) == NULL)
 854                         {
 855                         SSLerr(SSL_F_SSL_PREPARE_CLIENTHELLO_TLSEXT,ERR_R_MALLOC_FAILURE);
 856                         return -1;
 857                         }
 858                 s->tlsext_ecpointformatlist_length = 3;
 859                 s->tlsext_ecpointformatlist[0] = TLSEXT_ECPOINTFORMAT_uncompressed;
 860                 s->tlsext_ecpointformatlist[1] = TLSEXT_ECPOINTFORMAT_ansiX962_compressed_prime;
 861                 s->tlsext_ecpointformatlist[2] = TLSEXT_ECPOINTFORMAT_ansiX962_compressed_char2;
 862
 863                 /* we support all named elliptic curves in draft-ietf-tls-ecc-12 */
 864                 if (s->tlsext_ellipticcurvelist != NULL) OPENSSL_free(s->tlsext_ellipticcurvelist);
 865                 s->tlsext_ellipticcurvelist_length = sizeof(nid_list)/sizeof(nid_list[0]) * 2;
 866                 if ((s->tlsext_ellipticcurvelist = OPENSSL_malloc(s->tlsext_ellipticcurvelist_length)) == NULL)
 867                         {
 868                         s->tlsext_ellipticcurvelist_length = 0;
 869                         SSLerr(SSL_F_SSL_PREPARE_CLIENTHELLO_TLSEXT,ERR_R_MALLOC_FAILURE);
 870                         return -1;
 871                         }
 872                 for (i = 1, j = s->tlsext_ellipticcurvelist; i <= sizeof(nid_list)/sizeof(nid_list[0]); i++)
 873                         s2n(i,j);
 874                 }
 875 #endif /* OPENSSL_NO_EC */
 876
 877 #ifdef TLSEXT_TYPE_opaque_prf_input
 878         {
 879                 int r = 1;
 880
 881                 if (s->ctx->tlsext_opaque_prf_input_callback != 0)
 882                         {
 883                         r = s->ctx->tlsext_opaque_prf_input_callback(s, NULL, 0, s->ctx->tlsext_opaque_prf_input_callback_arg);
 884                         if (!r)
 885                                 return -1;
 886                         }
 887
 888                 if (s->tlsext_opaque_prf_input != NULL)
 889                         {
 890                         if (s->s3->client_opaque_prf_input != NULL) /* shouldn't really happen */
 891                                 OPENSSL_free(s->s3->client_opaque_prf_input);
 892
 893                         s->s3->client_opaque_prf_input = BUF_memdup(s->tlsext_opaque_prf_input, s->tlsext_opaque_prf_input_len);
 894                         if (s->s3->client_opaque_prf_input == NULL)
 895                                 {
 896                                 SSLerr(SSL_F_SSL_PREPARE_CLIENTHELLO_TLSEXT,ERR_R_MALLOC_FAILURE);
 897                                 return -1;
 898                                 }
 899                         s->s3->client_opaque_prf_input_len = s->tlsext_opaque_prf_input_len;
 900                         }
 901
 902                 if (r == 2)
 903                         /* at callback's request, insist on receiving an appropriate server opaque PRF input */
 904                         s->s3->server_opaque_prf_input_len = s->tlsext_opaque_prf_input_len;
 905         }
 906 #endif
 907
 908         return 1;
 909         }
 910
 911 int ssl_prepare_serverhello_tlsext(SSL *s)
 912         {
 913 #ifndef OPENSSL_NO_EC
 914         /* If we are server and using an ECC cipher suite, send the point formats we support
 915          * if the client sent us an ECPointsFormat extension.  Note that the server is not
 916          * supposed to send an EllipticCurves extension.
 917          */
 918
 919         unsigned long alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
 920         unsigned long alg_a = s->s3->tmp.new_cipher->algorithm_auth;
 921         int using_ecc = (alg_k & (SSL_kEECDH|SSL_kECDHr|SSL_kECDHe)) || (alg_a & SSL_aECDSA);
 922         using_ecc = using_ecc && (s->session->tlsext_ecpointformatlist != NULL);
 923
 924         if (using_ecc)
 925                 {
 926                 if (s->tlsext_ecpointformatlist != NULL) OPENSSL_free(s->tlsext_ecpointformatlist);
 927                 if ((s->tlsext_ecpointformatlist = OPENSSL_malloc(3)) == NULL)
 928                         {
 929                         SSLerr(SSL_F_SSL_PREPARE_SERVERHELLO_TLSEXT,ERR_R_MALLOC_FAILURE);
 930                         return -1;
 931                         }
 932                 s->tlsext_ecpointformatlist_length = 3;
 933                 s->tlsext_ecpointformatlist[0] = TLSEXT_ECPOINTFORMAT_uncompressed;
 934                 s->tlsext_ecpointformatlist[1] = TLSEXT_ECPOINTFORMAT_ansiX962_compressed_prime;
 935                 s->tlsext_ecpointformatlist[2] = TLSEXT_ECPOINTFORMAT_ansiX962_compressed_char2;
 936                 }
 937 #endif /* OPENSSL_NO_EC */
 938
 939         return 1;
 940         }
 941
 942 int ssl_check_clienthello_tlsext(SSL *s)
 943         {
 944         int ret=SSL_TLSEXT_ERR_NOACK;
 945         int al = SSL_AD_UNRECOGNIZED_NAME;
 946
 947 #ifndef OPENSSL_NO_EC
 948         /* The handling of the ECPointFormats extension is done elsewhere, namely in
 949          * ssl3_choose_cipher in s3_lib.c.
 950          */
 951         /* The handling of the EllipticCurves extension is done elsewhere, namely in
 952          * ssl3_choose_cipher in s3_lib.c.
 953          */
 954 #endif
 955
 956         if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0)
 957                 ret = s->ctx->tlsext_servername_callback(s, &al, s->ctx->tlsext_servername_arg);
 958         else if (s->initial_ctx != NULL && s->initial_ctx->tlsext_servername_callback != 0)
 959                 ret = s->initial_ctx->tlsext_servername_callback(s, &al, s->initial_ctx->tlsext_servername_arg);
 960
 961
 962 #ifdef TLSEXT_TYPE_opaque_prf_input
 963         {
 964                 /* This sort of belongs into ssl_prepare_serverhello_tlsext(),
 965                  * but we might be sending an alert in response to the client hello,
 966                  * so this has to happen here in ssl_check_clienthello_tlsext(). */
 967
 968                 int r = 1;
 969
 970                 if (s->ctx->tlsext_opaque_prf_input_callback != 0)
 971                         {
 972                         r = s->ctx->tlsext_opaque_prf_input_callback(s, NULL, 0, s->ctx->tlsext_opaque_prf_input_callback_arg);
 973                         if (!r)
 974                                 {
 975                                 ret = SSL_TLSEXT_ERR_ALERT_FATAL;
 976                                 al = SSL_AD_INTERNAL_ERROR;
 977                                 goto err;
 978                                 }
 979                         }
 980
 981                 if (s->s3->server_opaque_prf_input != NULL) /* shouldn't really happen */
 982                         OPENSSL_free(s->s3->server_opaque_prf_input);
 983                 s->s3->server_opaque_prf_input = NULL;
 984
 985                 if (s->tlsext_opaque_prf_input != NULL)
 986                         {
 987                         if (s->s3->client_opaque_prf_input != NULL &&
 988                                 s->s3->client_opaque_prf_input_len == s->tlsext_opaque_prf_input_len)
 989                                 {
 990                                 /* can only use this extension if we have a server opaque PRF input
 991                                  * of the same length as the client opaque PRF input! */
 992
 993                                 s->s3->server_opaque_prf_input = BUF_memdup(s->tlsext_opaque_prf_input, s->tlsext_opaque_prf_input_len);
 994                                 if (s->s3->server_opaque_prf_input == NULL)
 995                                         {
 996                                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
 997                                         al = SSL_AD_INTERNAL_ERROR;
 998                                         goto err;
 999                                         }
1000                                 s->s3->server_opaque_prf_input_len = s->tlsext_opaque_prf_input_len;
1001                                 }
1002                         }
1003
1004                 if (r == 2 && s->s3->server_opaque_prf_input == NULL)
1005                         {
1006                         /* The callback wants to enforce use of the extension,
1007                          * but we can't do that with the client opaque PRF input;
1008                          * abort the handshake.
1009                          */
1010                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
1011                         al = SSL_AD_HANDSHAKE_FAILURE;
1012                         }
1013         }
1014 #endif
1015
1016  err:
1017         switch (ret)
1018                 {
1019                 case SSL_TLSEXT_ERR_ALERT_FATAL:
1020                         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1021                         return -1;
1022
1023                 case SSL_TLSEXT_ERR_ALERT_WARNING:
1024                         ssl3_send_alert(s,SSL3_AL_WARNING,al);
1025                         return 1;
1026
1027                 case SSL_TLSEXT_ERR_NOACK:
1028                         s->servername_done=0;
1029                         default:
1030                 return 1;
1031                 }
1032         }
1033
1034 int ssl_check_serverhello_tlsext(SSL *s)
1035         {
1036         int ret=SSL_TLSEXT_ERR_NOACK;
1037         int al = SSL_AD_UNRECOGNIZED_NAME;
1038
1039 #ifndef OPENSSL_NO_EC
1040         /* If we are client and using an elliptic curve cryptography cipher suite, then server
1041          * must return a an EC point formats lists containing uncompressed.
1042          */
1043         unsigned long alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
1044         unsigned long alg_a = s->s3->tmp.new_cipher->algorithm_auth;
1045         if ((s->tlsext_ecpointformatlist != NULL) && (s->tlsext_ecpointformatlist_length > 0) &&
1046             ((alg_k & (SSL_kEECDH|SSL_kECDHr|SSL_kECDHe)) || (alg_a & SSL_aECDSA)))
1047                 {
1048                 /* we are using an ECC cipher */
1049                 size_t i;
1050                 unsigned char *list;
1051                 int found_uncompressed = 0;
1052                 if ((s->session->tlsext_ecpointformatlist == NULL) || (s->session->tlsext_ecpointformatlist_length == 0))
1053                         {
1054                         SSLerr(SSL_F_SSL_CHECK_SERVERHELLO_TLSEXT,SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST);
1055                         return -1;
1056                         }
1057                 list = s->session->tlsext_ecpointformatlist;
1058                 for (i = 0; i < s->session->tlsext_ecpointformatlist_length; i++)
1059                         {
1060                         if (*(list++) == TLSEXT_ECPOINTFORMAT_uncompressed)
1061                                 {
1062                                 found_uncompressed = 1;
1063                                 break;
1064                                 }
1065                         }
1066                 if (!found_uncompressed)
1067                         {
1068                         SSLerr(SSL_F_SSL_CHECK_SERVERHELLO_TLSEXT,SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST);
1069                         return -1;
1070                         }
1071                 }
1072         ret = SSL_TLSEXT_ERR_OK;
1073 #endif /* OPENSSL_NO_EC */
1074
1075         if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0)
1076                 ret = s->ctx->tlsext_servername_callback(s, &al, s->ctx->tlsext_servername_arg);
1077         else if (s->initial_ctx != NULL && s->initial_ctx->tlsext_servername_callback != 0)
1078                 ret = s->initial_ctx->tlsext_servername_callback(s, &al, s->initial_ctx->tlsext_servername_arg);
1079
1080 #ifdef TLSEXT_TYPE_opaque_prf_input
1081         if (s->s3->server_opaque_prf_input_len > 0)
1082                 {
1083                 /* This case may indicate that we, as a client, want to insist on using opaque PRF inputs.
1084                  * So first verify that we really have a value from the server too. */
1085
1086                 if (s->s3->server_opaque_prf_input == NULL)
1087                         {
1088                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
1089                         al = SSL_AD_HANDSHAKE_FAILURE;
1090                         }
1091
1092                 /* Anytime the server *has* sent an opaque PRF input, we need to check
1093                  * that we have a client opaque PRF input of the same size. */
1094                 if (s->s3->client_opaque_prf_input == NULL ||
1095                     s->s3->client_opaque_prf_input_len != s->s3->server_opaque_prf_input_len)
1096                         {
1097                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
1098                         al = SSL_AD_ILLEGAL_PARAMETER;
1099                         }
1100                 }
1101 #endif
1102
1103         switch (ret)
1104                 {
1105                 case SSL_TLSEXT_ERR_ALERT_FATAL:
1106                         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1107                         return -1;
1108
1109                 case SSL_TLSEXT_ERR_ALERT_WARNING:
1110                         ssl3_send_alert(s,SSL3_AL_WARNING,al);
1111                         return 1;
1112
1113                 case SSL_TLSEXT_ERR_NOACK:
1114                         s->servername_done=0;
1115                         default:
1116                 return 1;
1117                 }
1118         }
1119
1120 /* Since the server cache lookup is done early on in the processing of client
1121  * hello and other operations depend on the result we need to handle any TLS
1122  * session ticket extension at the same time.
1123  */
1124
1125 int tls1_process_ticket(SSL *s, unsigned char *session_id, int len,
1126                                 const unsigned char *limit, SSL_SESSION **ret)
1127         {
1128         /* Point after session ID in client hello */
1129         const unsigned char *p = session_id + len;
1130         unsigned short i;
1131         if ((s->version <= SSL3_VERSION) || !limit)
1132                 return 1;
1133         if (p >= limit)
1134                 return -1;
1135         /* Skip past cipher list */
1136         n2s(p, i);
1137         p+= i;
1138         if (p >= limit)
1139                 return -1;
1140         /* Skip past compression algorithm list */
1141         i = *(p++);
1142         p += i;
1143         if (p > limit)
1144                 return -1;
1145         /* Now at start of extensions */
1146         if ((p + 2) >= limit)
1147                 return 1;
1148         n2s(p, i);
1149         while ((p + 4) <= limit)
1150                 {
1151                 unsigned short type, size;
1152                 n2s(p, type);
1153                 n2s(p, size);
1154                 if (p + size > limit)
1155                         return 1;
1156                 if (type == TLSEXT_TYPE_session_ticket)
1157                         {
1158                         /* If tickets disabled indicate cache miss which will
1159                          * trigger a full handshake
1160                          */
1161                         if (SSL_get_options(s) & SSL_OP_NO_TICKET)
1162                                 return 0;
1163                         /* If zero length not client will accept a ticket
1164                          * and indicate cache miss to trigger full handshake
1165                          */
1166                         if (size == 0)
1167                                 {
1168                                 s->tlsext_ticket_expected = 1;
1169                                 return 0;       /* Cache miss */
1170                                 }
1171                         return tls_decrypt_ticket(s, p, size, session_id, len,
1172                                                                         ret);
1173                         }
1174                 p += size;
1175                 }
1176         return 1;
1177         }
1178
1179 static int tls_decrypt_ticket(SSL *s, const unsigned char *etick, int eticklen,
1180                                 const unsigned char *sess_id, int sesslen,
1181                                 SSL_SESSION **psess)
1182         {
1183         SSL_SESSION *sess;
1184         unsigned char *sdec;
1185         const unsigned char *p;
1186         int slen, mlen;
1187         unsigned char tick_hmac[EVP_MAX_MD_SIZE];
1188         HMAC_CTX hctx;
1189         EVP_CIPHER_CTX ctx;
1190         /* Attempt to process session ticket, first conduct sanity and
1191          * integrity checks on ticket.
1192          */
1193         mlen = EVP_MD_size(tlsext_tick_md());
1194         eticklen -= mlen;
1195         /* Need at least keyname + iv + some encrypted data */
1196         if (eticklen < 48)
1197                 goto tickerr;
1198         /* Check key name matches */
1199         if (memcmp(etick, s->ctx->tlsext_tick_key_name, 16))
1200                 goto tickerr;
1201         /* Check HMAC of encrypted ticket */
1202         HMAC_CTX_init(&hctx);
1203         HMAC_Init_ex(&hctx, s->ctx->tlsext_tick_hmac_key, 16,
1204                                 tlsext_tick_md(), NULL);
1205         HMAC_Update(&hctx, etick, eticklen);
1206         HMAC_Final(&hctx, tick_hmac, NULL);
1207         HMAC_CTX_cleanup(&hctx);
1208         if (memcmp(tick_hmac, etick + eticklen, mlen))
1209                 goto tickerr;
1210         /* Set p to start of IV */
1211         p = etick + 16;
1212         EVP_CIPHER_CTX_init(&ctx);
1213         /* Attempt to decrypt session data */
1214         EVP_DecryptInit_ex(&ctx, EVP_aes_128_cbc(), NULL,
1215                                         s->ctx->tlsext_tick_aes_key, p);
1216         /* Move p after IV to start of encrypted ticket, update length */
1217         p += 16;
1218         eticklen -= 32;
1219         sdec = OPENSSL_malloc(eticklen);
1220         if (!sdec)
1221                 {
1222                 EVP_CIPHER_CTX_cleanup(&ctx);
1223                 return -1;
1224                 }
1225         EVP_DecryptUpdate(&ctx, sdec, &slen, p, eticklen);
1226         if (EVP_DecryptFinal(&ctx, sdec + slen, &mlen) <= 0)
1227                 goto tickerr;
1228         slen += mlen;
1229         EVP_CIPHER_CTX_cleanup(&ctx);
1230         p = sdec;
1231
1232         sess = d2i_SSL_SESSION(NULL, &p, slen);
1233         OPENSSL_free(sdec);
1234         if (sess)
1235                 {
1236                 /* The session ID if non-empty is used by some clients to
1237                  * detect that the ticket has been accepted. So we copy it to
1238                  * the session structure. If it is empty set length to zero
1239                  * as required by standard.
1240                  */
1241                 if (sesslen)
1242                         memcpy(sess->session_id, sess_id, sesslen);
1243                 sess->session_id_length = sesslen;
1244                 *psess = sess;
1245                 return 1;
1246                 }
1247         /* If session decrypt failure indicate a cache miss and set state to
1248          * send a new ticket
1249          */
1250         tickerr:
1251         s->tlsext_ticket_expected = 1;
1252         return 0;
1253         }
1254
1255 #endif