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 #include <stdio.h>
  60 #include <openssl/objects.h>
  61 #include <openssl/evp.h>
  62 #include <openssl/hmac.h>
  63 #include <openssl/ocsp.h>
  64 #include "ssl_locl.h"
  65
  66 const char tls1_version_str[]="TLSv1" OPENSSL_VERSION_PTEXT;
  67
  68 #ifndef OPENSSL_NO_TLSEXT
  69 static int tls_decrypt_ticket(SSL *s, const unsigned char *tick, int ticklen,
  70                                 const unsigned char *sess_id, int sesslen,
  71                                 SSL_SESSION **psess);
  72 #endif
  73
  74 SSL3_ENC_METHOD TLSv1_enc_data={
  75         tls1_enc,
  76         tls1_mac,
  77         tls1_setup_key_block,
  78         tls1_generate_master_secret,
  79         tls1_change_cipher_state,
  80         tls1_final_finish_mac,
  81         TLS1_FINISH_MAC_LENGTH,
  82         tls1_cert_verify_mac,
  83         TLS_MD_CLIENT_FINISH_CONST,TLS_MD_CLIENT_FINISH_CONST_SIZE,
  84         TLS_MD_SERVER_FINISH_CONST,TLS_MD_SERVER_FINISH_CONST_SIZE,
  85         tls1_alert_code,
  86         };
  87
  88 long tls1_default_timeout(void)
  89         {
  90         /* 2 hours, the 24 hours mentioned in the TLSv1 spec
  91          * is way too long for http, the cache would over fill */
  92         return(60*60*2);
  93         }
  94
  95 IMPLEMENT_tls1_meth_func(tlsv1_base_method,
  96                         ssl_undefined_function,
  97                         ssl_undefined_function,
  98                         ssl_bad_method)
  99
 100 int tls1_new(SSL *s)
 101         {
 102         if (!ssl3_new(s)) return(0);
 103         s->method->ssl_clear(s);
 104         return(1);
 105         }
 106
 107 void tls1_free(SSL *s)
 108         {
 109         ssl3_free(s);
 110         }
 111
 112 void tls1_clear(SSL *s)
 113         {
 114         ssl3_clear(s);
 115         s->version=TLS1_VERSION;
 116         }
 117
 118 #if 0
 119 long tls1_ctrl(SSL *s, int cmd, long larg, char *parg)
 120         {
 121         return(0);
 122         }
 123
 124 long tls1_callback_ctrl(SSL *s, int cmd, void *(*fp)())
 125         {
 126         return(0);
 127         }
 128 #endif
 129
 130 #ifndef OPENSSL_NO_TLSEXT
 131 unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned char *limit)
 132         {
 133         int extdatalen=0;
 134         unsigned char *ret = p;
 135
 136         /* don't add extensions for SSLv3 */
 137         if (s->client_version == SSL3_VERSION)
 138                 return p;
 139
 140         ret+=2;
 141
 142         if (ret>=limit) return NULL; /* this really never occurs, but ... */
 143
 144         if (s->tlsext_hostname != NULL)
 145                 {
 146                 /* Add TLS extension servername to the Client Hello message */
 147                 unsigned long size_str;
 148                 long lenmax;
 149
 150                 /* check for enough space.
 151                    4 for the servername type and entension length
 152                    2 for servernamelist length
 153                    1 for the hostname type
 154                    2 for hostname length
 155                    + hostname length
 156                 */
 157
 158                 if ((lenmax = limit - ret - 9) < 0
 159                 || (size_str = strlen(s->tlsext_hostname)) > (unsigned long)lenmax)
 160                         return NULL;
 161
 162                 /* extension type and length */
 163                 s2n(TLSEXT_TYPE_server_name,ret);
 164                 s2n(size_str+5,ret);
 165
 166                 /* length of servername list */
 167                 s2n(size_str+3,ret);
 168
 169                 /* hostname type, length and hostname */
 170                 *(ret++) = (unsigned char) TLSEXT_NAMETYPE_host_name;
 171                 s2n(size_str,ret);
 172                 memcpy(ret, s->tlsext_hostname, size_str);
 173                 ret+=size_str;
 174
 175                 }
 176
 177         if (!(SSL_get_options(s) & SSL_OP_NO_TICKET))
 178                 {
 179                 int ticklen;
 180                 if (s->session && s->session->tlsext_tick)
 181                         ticklen = s->session->tlsext_ticklen;
 182                 else
 183                         ticklen = 0;
 184                 /* Check for enough room 2 for extension type, 2 for len
 185                  * rest for ticket
 186                  */
 187                 if (limit - ret - 4 - ticklen < 0)
 188                         return NULL;
 189                 s2n(TLSEXT_TYPE_session_ticket,ret);
 190                 s2n(ticklen,ret);
 191                 if (ticklen)
 192                         {
 193                         memcpy(ret, s->session->tlsext_tick, ticklen);
 194                         ret += ticklen;
 195                         }
 196                 }
 197
 198         if (s->tlsext_status_type == TLSEXT_STATUSTYPE_ocsp)
 199                 {
 200                 int i;
 201                 long extlen, idlen, itmp;
 202                 OCSP_RESPID *id;
 203
 204                 idlen = 0;
 205                 for (i = 0; i < sk_OCSP_RESPID_num(s->tlsext_ocsp_ids); i++)
 206                         {
 207                         id = sk_OCSP_RESPID_value(s->tlsext_ocsp_ids, i);
 208                         itmp = i2d_OCSP_RESPID(id, NULL);
 209                         if (itmp <= 0)
 210                                 return NULL;
 211                         idlen += itmp + 2;
 212                         }
 213
 214                 if (s->tlsext_ocsp_exts)
 215                         {
 216                         extlen = i2d_X509_EXTENSIONS(s->tlsext_ocsp_exts, NULL);
 217                         if (extlen < 0)
 218                                 return NULL;
 219                         }
 220                 else
 221                         extlen = 0;
 222
 223                 if ((long)(limit - ret - 7 - extlen - idlen) < 0) return NULL;
 224                 s2n(TLSEXT_TYPE_status_request, ret);
 225                 if (extlen + idlen > 0xFFF0)
 226                         return NULL;
 227                 s2n(extlen + idlen + 5, ret);
 228                 *(ret++) = TLSEXT_STATUSTYPE_ocsp;
 229                 s2n(idlen, ret);
 230                 for (i = 0; i < sk_OCSP_RESPID_num(s->tlsext_ocsp_ids); i++)
 231                         {
 232                         /* save position of id len */
 233                         unsigned char *q = ret;
 234                         id = sk_OCSP_RESPID_value(s->tlsext_ocsp_ids, i);
 235                         /* skip over id len */
 236                         ret += 2;
 237                         itmp = i2d_OCSP_RESPID(id, &ret);
 238                         /* write id len */
 239                         s2n(itmp, q);
 240                         }
 241                 s2n(extlen, ret);
 242                 if (extlen > 0)
 243                         i2d_X509_EXTENSIONS(s->tlsext_ocsp_exts, &ret);
 244                 }
 245
 246         if ((extdatalen = ret-p-2)== 0)
 247                 return p;
 248
 249         s2n(extdatalen,p);
 250         return ret;
 251         }
 252
 253 unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *p, unsigned char *limit)
 254         {
 255         int extdatalen=0;
 256         unsigned char *ret = p;
 257
 258         /* don't add extensions for SSLv3 */
 259         if (s->version == SSL3_VERSION)
 260                 return p;
 261
 262         ret+=2;
 263         if (ret>=limit) return NULL; /* this really never occurs, but ... */
 264
 265         if (!s->hit && s->servername_done == 1 && s->session->tlsext_hostname != NULL)
 266                 {
 267                 if (limit - ret - 4 < 0) return NULL;
 268
 269                 s2n(TLSEXT_TYPE_server_name,ret);
 270                 s2n(0,ret);
 271                 }
 272
 273         if (s->tlsext_ticket_expected
 274                 && !(SSL_get_options(s) & SSL_OP_NO_TICKET))
 275                 {
 276                 if (limit - ret - 4 < 0) return NULL;
 277                 s2n(TLSEXT_TYPE_session_ticket,ret);
 278                 s2n(0,ret);
 279                 }
 280
 281         if (s->tlsext_status_expected)
 282                 {
 283                 if ((long)(limit - ret - 4) < 0) return NULL;
 284                 s2n(TLSEXT_TYPE_status_request,ret);
 285                 s2n(0,ret);
 286                 }
 287
 288         if ((extdatalen = ret-p-2)== 0)
 289                 return p;
 290
 291         s2n(extdatalen,p);
 292         return ret;
 293         }
 294
 295 int ssl_parse_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char *d, int n, int *al)
 296         {
 297         unsigned short type;
 298         unsigned short size;
 299         unsigned short len;
 300         unsigned char *data = *p;
 301         s->servername_done = 0;
 302         s->tlsext_status_type = -1;
 303
 304         if (data >= (d+n-2))
 305                 return 1;
 306         n2s(data,len);
 307
 308         if (data > (d+n-len))
 309                 return 1;
 310
 311         while (data <= (d+n-4))
 312                 {
 313                 n2s(data,type);
 314                 n2s(data,size);
 315
 316                 if (data+size > (d+n))
 317                         return 1;
 318
 319                 if (s->tlsext_debug_cb)
 320                         s->tlsext_debug_cb(s, 0, type, data, size,
 321                                                 s->tlsext_debug_arg);
 322 /* The servername extension is treated as follows:
 323
 324    - Only the hostname type is supported with a maximum length of 255.
 325    - The servername is rejected if too long or if it contains zeros,
 326      in which case an fatal alert is generated.
 327    - The servername field is maintained together with the session cache.
 328    - When a session is resumed, the servername call back invoked in order
 329      to allow the application to position itself to the right context.
 330    - The servername is acknowledged if it is new for a session or when
 331      it is identical to a previously used for the same session.
 332      Applications can control the behaviour.  They can at any time
 333      set a 'desirable' servername for a new SSL object. This can be the
 334      case for example with HTTPS when a Host: header field is received and
 335      a renegotiation is requested. In this case, a possible servername
 336      presented in the new client hello is only acknowledged if it matches
 337      the value of the Host: field.
 338    - Applications must  use SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION
 339      if they provide for changing an explicit servername context for the session,
 340      i.e. when the session has been established with a servername extension.
 341    - On session reconnect, the servername extension may be absent.
 342
 343 */
 344
 345                 if (type == TLSEXT_TYPE_server_name)
 346                         {
 347                         unsigned char *sdata;
 348                         int servname_type;
 349                         int dsize;
 350
 351                         if (size < 2)
 352                                 {
 353                                 *al = SSL_AD_DECODE_ERROR;
 354                                 return 0;
 355                                 }
 356                         n2s(data,dsize);
 357                         size -= 2;
 358                         if (dsize > size  )
 359                                 {
 360                                 *al = SSL_AD_DECODE_ERROR;
 361                                 return 0;
 362                                 }
 363
 364                         sdata = data;
 365                         while (dsize > 3)
 366                                 {
 367                                 servname_type = *(sdata++);
 368                                 n2s(sdata,len);
 369                                 dsize -= 3;
 370
 371                                 if (len > dsize)
 372                                         {
 373                                         *al = SSL_AD_DECODE_ERROR;
 374                                         return 0;
 375                                         }
 376                                 if (s->servername_done == 0)
 377                                 switch (servname_type)
 378                                         {
 379                                 case TLSEXT_NAMETYPE_host_name:
 380                                         if (s->session->tlsext_hostname == NULL)
 381                                                 {
 382                                                 if (len > TLSEXT_MAXLEN_host_name ||
 383                                                         ((s->session->tlsext_hostname = OPENSSL_malloc(len+1)) == NULL))
 384                                                         {
 385                                                         *al = TLS1_AD_UNRECOGNIZED_NAME;
 386                                                         return 0;
 387                                                         }
 388                                                 memcpy(s->session->tlsext_hostname, sdata, len);
 389                                                 s->session->tlsext_hostname[len]='\0';
 390                                                 if (strlen(s->session->tlsext_hostname) != len) {
 391                                                         OPENSSL_free(s->session->tlsext_hostname);
 392                                                         s->session->tlsext_hostname = NULL;
 393                                                         *al = TLS1_AD_UNRECOGNIZED_NAME;
 394                                                         return 0;
 395                                                 }
 396                                                 s->servername_done = 1;
 397
 398                                                 }
 399                                         else
 400                                                 s->servername_done = strlen(s->session->tlsext_hostname) == len
 401                                                         && strncmp(s->session->tlsext_hostname, (char *)sdata, len) == 0;
 402
 403                                         break;
 404
 405                                 default:
 406                                         break;
 407                                         }
 408
 409                                 dsize -= len;
 410                                 }
 411                         if (dsize != 0)
 412                                 {
 413                                 *al = SSL_AD_DECODE_ERROR;
 414                                 return 0;
 415                                 }
 416
 417                         }
 418                 else if (type == TLSEXT_TYPE_status_request
 419                                                 && s->ctx->tlsext_status_cb)
 420                         {
 421
 422                         if (size < 5)
 423                                 {
 424                                 *al = SSL_AD_DECODE_ERROR;
 425                                 return 0;
 426                                 }
 427
 428                         s->tlsext_status_type = *data++;
 429                         size--;
 430                         if (s->tlsext_status_type == TLSEXT_STATUSTYPE_ocsp)
 431                                 {
 432                                 const unsigned char *sdata;
 433                                 int dsize;
 434                                 /* Read in responder_id_list */
 435                                 n2s(data,dsize);
 436                                 size -= 2;
 437                                 if (dsize > size  )
 438                                         {
 439                                         *al = SSL_AD_DECODE_ERROR;
 440                                         return 0;
 441                                         }
 442                                 while (dsize > 0)
 443                                         {
 444                                         OCSP_RESPID *id;
 445                                         int idsize;
 446                                         if (dsize < 4)
 447                                                 {
 448                                                 *al = SSL_AD_DECODE_ERROR;
 449                                                 return 0;
 450                                                 }
 451                                         n2s(data, idsize);
 452                                         dsize -= 2 + idsize;
 453                                         if (dsize < 0)
 454                                                 {
 455                                                 *al = SSL_AD_DECODE_ERROR;
 456                                                 return 0;
 457                                                 }
 458                                         sdata = data;
 459                                         data += idsize;
 460                                         id = d2i_OCSP_RESPID(NULL,
 461                                                                 &sdata, idsize);
 462                                         if (!id)
 463                                                 {
 464                                                 *al = SSL_AD_DECODE_ERROR;
 465                                                 return 0;
 466                                                 }
 467                                         if (data != sdata)
 468                                                 {
 469                                                 OCSP_RESPID_free(id);
 470                                                 *al = SSL_AD_DECODE_ERROR;
 471                                                 return 0;
 472                                                 }
 473                                         if (!s->tlsext_ocsp_ids
 474                                                 && !(s->tlsext_ocsp_ids =
 475                                                 sk_OCSP_RESPID_new_null()))
 476                                                 {
 477                                                 OCSP_RESPID_free(id);
 478                                                 *al = SSL_AD_INTERNAL_ERROR;
 479                                                 return 0;
 480                                                 }
 481                                         if (!sk_OCSP_RESPID_push(
 482                                                         s->tlsext_ocsp_ids, id))
 483                                                 {
 484                                                 OCSP_RESPID_free(id);
 485                                                 *al = SSL_AD_INTERNAL_ERROR;
 486                                                 return 0;
 487                                                 }
 488                                         }
 489
 490                                 /* Read in request_extensions */
 491                                 n2s(data,dsize);
 492                                 size -= 2;
 493                                 if (dsize > size)
 494                                         {
 495                                         *al = SSL_AD_DECODE_ERROR;
 496                                         return 0;
 497                                         }
 498                                 sdata = data;
 499                                 if (dsize > 0)
 500                                         {
 501                                         s->tlsext_ocsp_exts =
 502                                                 d2i_X509_EXTENSIONS(NULL,
 503                                                         &sdata, dsize);
 504                                         if (!s->tlsext_ocsp_exts
 505                                                 || (data + dsize != sdata))
 506                                                 {
 507                                                 *al = SSL_AD_DECODE_ERROR;
 508                                                 return 0;
 509                                                 }
 510                                         }
 511                                 }
 512                                 /* We don't know what to do with any other type
 513                                 * so ignore it.
 514                                 */
 515                                 else
 516                                         s->tlsext_status_type = -1;
 517                         }
 518                 /* session ticket processed earlier */
 519
 520                 data+=size;
 521                 }
 522
 523         *p = data;
 524         return 1;
 525         }
 526
 527 int ssl_parse_serverhello_tlsext(SSL *s, unsigned char **p, unsigned char *d, int n, int *al)
 528         {
 529         unsigned short type;
 530         unsigned short size;
 531         unsigned short len;
 532         unsigned char *data = *p;
 533
 534         int tlsext_servername = 0;
 535
 536         if (data >= (d+n-2))
 537                 return 1;
 538
 539         n2s(data,len);
 540
 541         while(data <= (d+n-4))
 542                 {
 543                 n2s(data,type);
 544                 n2s(data,size);
 545
 546                 if (data+size > (d+n))
 547                         return 1;
 548
 549                 if (s->tlsext_debug_cb)
 550                         s->tlsext_debug_cb(s, 1, type, data, size,
 551                                                 s->tlsext_debug_arg);
 552
 553                 if (type == TLSEXT_TYPE_server_name)
 554                         {
 555                         if (s->tlsext_hostname == NULL || size > 0)
 556                                 {
 557                                 *al = TLS1_AD_UNRECOGNIZED_NAME;
 558                                 return 0;
 559                                 }
 560                         tlsext_servername = 1;
 561                         }
 562                 else if (type == TLSEXT_TYPE_session_ticket)
 563                         {
 564                         if ((SSL_get_options(s) & SSL_OP_NO_TICKET)
 565                                 || (size > 0))
 566                                 {
 567                                 *al = TLS1_AD_UNSUPPORTED_EXTENSION;
 568                                 return 0;
 569                                 }
 570                         s->tlsext_ticket_expected = 1;
 571                         }
 572                 else if (type == TLSEXT_TYPE_status_request)
 573                         {
 574                         /* MUST be empty and only sent if we've requested
 575                          * a status request message.
 576                          */
 577                         if ((s->tlsext_status_type == -1) || (size > 0))
 578                                 {
 579                                 *al = TLS1_AD_UNSUPPORTED_EXTENSION;
 580                                 return 0;
 581                                 }
 582                         /* Set flag to expect CertificateStatus message */
 583                         s->tlsext_status_expected = 1;
 584                         }
 585
 586                 data+=size;
 587                 }
 588
 589         if (data != d+n)
 590                 {
 591                 *al = SSL_AD_DECODE_ERROR;
 592                 return 0;
 593                 }
 594
 595         if (!s->hit && tlsext_servername == 1)
 596                 {
 597                 if (s->tlsext_hostname)
 598                         {
 599                         if (s->session->tlsext_hostname == NULL)
 600                                 {
 601                                 s->session->tlsext_hostname = BUF_strdup(s->tlsext_hostname);
 602                                 if (!s->session->tlsext_hostname)
 603                                         {
 604                                         *al = SSL_AD_UNRECOGNIZED_NAME;
 605                                         return 0;
 606                                         }
 607                                 }
 608                         else
 609                                 {
 610                                 *al = SSL_AD_DECODE_ERROR;
 611                                 return 0;
 612                                 }
 613                         }
 614                 }
 615
 616         *p = data;
 617         return 1;
 618         }
 619
 620 int ssl_check_clienthello_tlsext(SSL *s)
 621         {
 622         int ret=SSL_TLSEXT_ERR_NOACK;
 623         int al = SSL_AD_UNRECOGNIZED_NAME;
 624
 625         if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0)
 626                 ret = s->ctx->tlsext_servername_callback(s, &al, s->ctx->tlsext_servername_arg);
 627         else if (s->initial_ctx != NULL && s->initial_ctx->tlsext_servername_callback != 0)
 628                 ret = s->initial_ctx->tlsext_servername_callback(s, &al, s->initial_ctx->tlsext_servername_arg);
 629
 630         /* If status request then ask callback what to do.
 631          * Note: this must be called after servername callbacks in case
 632          * the certificate has changed.
 633          */
 634         if ((s->tlsext_status_type != -1) && s->ctx->tlsext_status_cb)
 635                 {
 636                 int r;
 637                 r = s->ctx->tlsext_status_cb(s, s->ctx->tlsext_status_arg);
 638                 switch (r)
 639                         {
 640                         /* We don't want to send a status request response */
 641                         case SSL_TLSEXT_ERR_NOACK:
 642                                 s->tlsext_status_expected = 0;
 643                                 break;
 644                         /* status request response should be sent */
 645                         case SSL_TLSEXT_ERR_OK:
 646                                 if (s->tlsext_ocsp_resp)
 647                                         s->tlsext_status_expected = 1;
 648                                 else
 649                                         s->tlsext_status_expected = 0;
 650                                 break;
 651                         /* something bad happened */
 652                         case SSL_TLSEXT_ERR_ALERT_FATAL:
 653                                 ret = SSL_TLSEXT_ERR_ALERT_FATAL;
 654                                 al = SSL_AD_INTERNAL_ERROR;
 655                                 goto err;
 656                         }
 657                 }
 658         else
 659                 s->tlsext_status_expected = 0;
 660         err:
 661         switch (ret)
 662                 {
 663                 case SSL_TLSEXT_ERR_ALERT_FATAL:
 664                         ssl3_send_alert(s,SSL3_AL_FATAL,al);
 665                         return -1;
 666
 667                 case SSL_TLSEXT_ERR_ALERT_WARNING:
 668                         ssl3_send_alert(s,SSL3_AL_WARNING,al);
 669                         return 1;
 670
 671                 case SSL_TLSEXT_ERR_NOACK:
 672                         s->servername_done=0;
 673                         default:
 674                 return 1;
 675                 }
 676         }
 677
 678 int ssl_check_serverhello_tlsext(SSL *s)
 679         {
 680         int ret=SSL_TLSEXT_ERR_NOACK;
 681         int al = SSL_AD_UNRECOGNIZED_NAME;
 682
 683         if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0)
 684                 ret = s->ctx->tlsext_servername_callback(s, &al, s->ctx->tlsext_servername_arg);
 685         else if (s->initial_ctx != NULL && s->initial_ctx->tlsext_servername_callback != 0)
 686                 ret = s->initial_ctx->tlsext_servername_callback(s, &al, s->initial_ctx->tlsext_servername_arg);
 687
 688         /* If we've requested certificate status and we wont get one
 689          * tell the callback
 690          */
 691         if ((s->tlsext_status_type != -1) && !(s->tlsext_status_expected)
 692                         && s->ctx->tlsext_status_cb)
 693                 {
 694                 int r;
 695                 /* Set resp to NULL, resplen to -1 so callback knows
 696                  * there is no response.
 697                  */
 698                 if (s->tlsext_ocsp_resp)
 699                         {
 700                         OPENSSL_free(s->tlsext_ocsp_resp);
 701                         s->tlsext_ocsp_resp = NULL;
 702                         }
 703                 s->tlsext_ocsp_resplen = -1;
 704                 r = s->ctx->tlsext_status_cb(s, s->ctx->tlsext_status_arg);
 705                 if (r == 0)
 706                         {
 707                         al = SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE;
 708                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
 709                         }
 710                 if (r < 0)
 711                         {
 712                         al = SSL_AD_INTERNAL_ERROR;
 713                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
 714                         }
 715                 }
 716
 717         switch (ret)
 718                 {
 719                 case SSL_TLSEXT_ERR_ALERT_FATAL:
 720                         ssl3_send_alert(s,SSL3_AL_FATAL,al);
 721                         return -1;
 722
 723                 case SSL_TLSEXT_ERR_ALERT_WARNING:
 724                         ssl3_send_alert(s,SSL3_AL_WARNING,al);
 725                         return 1;
 726
 727                 case SSL_TLSEXT_ERR_NOACK:
 728                         s->servername_done=0;
 729                         default:
 730                 return 1;
 731                 }
 732         }
 733
 734 /* Since the server cache lookup is done early on in the processing of client
 735  * hello and other operations depend on the result we need to handle any TLS
 736  * session ticket extension at the same time.
 737  */
 738
 739 int tls1_process_ticket(SSL *s, unsigned char *session_id, int len,
 740                                 const unsigned char *limit, SSL_SESSION **ret)
 741         {
 742         /* Point after session ID in client hello */
 743         const unsigned char *p = session_id + len;
 744         unsigned short i;
 745
 746         /* If tickets disabled behave as if no ticket present
 747          * to permit stateful resumption.
 748          */
 749         if (SSL_get_options(s) & SSL_OP_NO_TICKET)
 750                 return 1;
 751
 752         if ((s->version <= SSL3_VERSION) || !limit)
 753                 return 1;
 754         if (p >= limit)
 755                 return -1;
 756         /* Skip past DTLS cookie */
 757         if (s->version == DTLS1_VERSION || s->version == DTLS1_BAD_VER)
 758                 {
 759                 i = *(p++);
 760                 p+= i;
 761                 if (p >= limit)
 762                         return -1;
 763                 }
 764         /* Skip past cipher list */
 765         n2s(p, i);
 766         p+= i;
 767         if (p >= limit)
 768                 return -1;
 769         /* Skip past compression algorithm list */
 770         i = *(p++);
 771         p += i;
 772         if (p > limit)
 773                 return -1;
 774         /* Now at start of extensions */
 775         if ((p + 2) >= limit)
 776                 return 1;
 777         n2s(p, i);
 778         while ((p + 4) <= limit)
 779                 {
 780                 unsigned short type, size;
 781                 n2s(p, type);
 782                 n2s(p, size);
 783                 if (p + size > limit)
 784                         return 1;
 785                 if (type == TLSEXT_TYPE_session_ticket)
 786                         {
 787                         /* If zero length note client will accept a ticket
 788                          * and indicate cache miss to trigger full handshake
 789                          */
 790                         if (size == 0)
 791                                 {
 792                                 s->tlsext_ticket_expected = 1;
 793                                 return 0;       /* Cache miss */
 794                                 }
 795                         return tls_decrypt_ticket(s, p, size, session_id, len,
 796                                                                         ret);
 797                         }
 798                 p += size;
 799                 }
 800         return 1;
 801         }
 802
 803 static int tls_decrypt_ticket(SSL *s, const unsigned char *etick, int eticklen,
 804                                 const unsigned char *sess_id, int sesslen,
 805                                 SSL_SESSION **psess)
 806         {
 807         SSL_SESSION *sess;
 808         unsigned char *sdec;
 809         const unsigned char *p;
 810         int slen, mlen, renew_ticket = 0;
 811         unsigned char tick_hmac[EVP_MAX_MD_SIZE];
 812         HMAC_CTX hctx;
 813         EVP_CIPHER_CTX ctx;
 814         /* Need at least keyname + iv + some encrypted data */
 815         if (eticklen < 48)
 816                 goto tickerr;
 817         /* Initialize session ticket encryption and HMAC contexts */
 818         HMAC_CTX_init(&hctx);
 819         EVP_CIPHER_CTX_init(&ctx);
 820         if (s->ctx->tlsext_ticket_key_cb)
 821                 {
 822                 unsigned char *nctick = (unsigned char *)etick;
 823                 int rv = s->ctx->tlsext_ticket_key_cb(s, nctick, nctick + 16,
 824                                                         &ctx, &hctx, 0);
 825                 if (rv < 0)
 826                         return -1;
 827                 if (rv == 0)
 828                         goto tickerr;
 829                 if (rv == 2)
 830                         renew_ticket = 1;
 831                 }
 832         else
 833                 {
 834                 /* Check key name matches */
 835                 if (memcmp(etick, s->ctx->tlsext_tick_key_name, 16))
 836                         goto tickerr;
 837                 HMAC_Init_ex(&hctx, s->ctx->tlsext_tick_hmac_key, 16,
 838                                         tlsext_tick_md(), NULL);
 839                 EVP_DecryptInit_ex(&ctx, EVP_aes_128_cbc(), NULL,
 840                                 s->ctx->tlsext_tick_aes_key, etick + 16);
 841                 }
 842         /* Attempt to process session ticket, first conduct sanity and
 843          * integrity checks on ticket.
 844          */
 845         mlen = HMAC_size(&hctx);
 846         eticklen -= mlen;
 847         /* Check HMAC of encrypted ticket */
 848         HMAC_Update(&hctx, etick, eticklen);
 849         HMAC_Final(&hctx, tick_hmac, NULL);
 850         HMAC_CTX_cleanup(&hctx);
 851         if (memcmp(tick_hmac, etick + eticklen, mlen))
 852                 goto tickerr;
 853         /* Attempt to decrypt session data */
 854         /* Move p after IV to start of encrypted ticket, update length */
 855         p = etick + 16 + EVP_CIPHER_CTX_iv_length(&ctx);
 856         eticklen -= 16 + EVP_CIPHER_CTX_iv_length(&ctx);
 857         sdec = OPENSSL_malloc(eticklen);
 858         if (!sdec)
 859                 {
 860                 EVP_CIPHER_CTX_cleanup(&ctx);
 861                 return -1;
 862                 }
 863         EVP_DecryptUpdate(&ctx, sdec, &slen, p, eticklen);
 864         if (EVP_DecryptFinal(&ctx, sdec + slen, &mlen) <= 0)
 865                 goto tickerr;
 866         slen += mlen;
 867         EVP_CIPHER_CTX_cleanup(&ctx);
 868         p = sdec;
 869
 870         sess = d2i_SSL_SESSION(NULL, &p, slen);
 871         OPENSSL_free(sdec);
 872         if (sess)
 873                 {
 874                 /* The session ID if non-empty is used by some clients to
 875                  * detect that the ticket has been accepted. So we copy it to
 876                  * the session structure. If it is empty set length to zero
 877                  * as required by standard.
 878                  */
 879                 if (sesslen)
 880                         memcpy(sess->session_id, sess_id, sesslen);
 881                 sess->session_id_length = sesslen;
 882                 *psess = sess;
 883                 s->tlsext_ticket_expected = renew_ticket;
 884                 return 1;
 885                 }
 886         /* If session decrypt failure indicate a cache miss and set state to
 887          * send a new ticket
 888          */
 889         tickerr:
 890         s->tlsext_ticket_expected = 1;
 891         return 0;
 892         }
 893
 894 #endif