ssl/t1_lib.c

   1 /* ssl/t1_lib.c */
   2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
   3  * All rights reserved.
   4  *
   5  * This package is an SSL implementation written
   6  * by Eric Young (eay@cryptsoft.com).
   7  * The implementation was written so as to conform with Netscapes SSL.
   8  *
   9  * This library is free for commercial and non-commercial use as long as
  10  * the following conditions are aheared to.  The following conditions
  11  * apply to all code found in this distribution, be it the RC4, RSA,
  12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  13  * included with this distribution is covered by the same copyright terms
  14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  15  *
  16  * Copyright remains Eric Young's, and as such any Copyright notices in
  17  * the code are not to be removed.
  18  * If this package is used in a product, Eric Young should be given attribution
  19  * as the author of the parts of the library used.
  20  * This can be in the form of a textual message at program startup or
  21  * in documentation (online or textual) provided with the package.
  22  *
  23  * Redistribution and use in source and binary forms, with or without
  24  * modification, are permitted provided that the following conditions
  25  * are met:
  26  * 1. Redistributions of source code must retain the copyright
  27  *    notice, this list of conditions and the following disclaimer.
  28  * 2. Redistributions in binary form must reproduce the above copyright
  29  *    notice, this list of conditions and the following disclaimer in the
  30  *    documentation and/or other materials provided with the distribution.
  31  * 3. All advertising materials mentioning features or use of this software
  32  *    must display the following acknowledgement:
  33  *    "This product includes cryptographic software written by
  34  *     Eric Young (eay@cryptsoft.com)"
  35  *    The word 'cryptographic' can be left out if the rouines from the library
  36  *    being used are not cryptographic related :-).
  37  * 4. If you include any Windows specific code (or a derivative thereof) from
  38  *    the apps directory (application code) you must include an acknowledgement:
  39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  40  *
  41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  51  * SUCH DAMAGE.
  52  *
  53  * The licence and distribution terms for any publically available version or
  54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  55  * copied and put under another distribution licence
  56  * [including the GNU Public Licence.]
  57  */
  58 /* ====================================================================
  59  * Copyright (c) 1998-2007 The OpenSSL Project.  All rights reserved.
  60  *
  61  * Redistribution and use in source and binary forms, with or without
  62  * modification, are permitted provided that the following conditions
  63  * are met:
  64  *
  65  * 1. Redistributions of source code must retain the above copyright
  66  *    notice, this list of conditions and the following disclaimer.
  67  *
  68  * 2. Redistributions in binary form must reproduce the above copyright
  69  *    notice, this list of conditions and the following disclaimer in
  70  *    the documentation and/or other materials provided with the
  71  *    distribution.
  72  *
  73  * 3. All advertising materials mentioning features or use of this
  74  *    software must display the following acknowledgment:
  75  *    "This product includes software developed by the OpenSSL Project
  76  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
  77  *
  78  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  79  *    endorse or promote products derived from this software without
  80  *    prior written permission. For written permission, please contact
  81  *    openssl-core@openssl.org.
  82  *
  83  * 5. Products derived from this software may not be called "OpenSSL"
  84  *    nor may "OpenSSL" appear in their names without prior written
  85  *    permission of the OpenSSL Project.
  86  *
  87  * 6. Redistributions of any form whatsoever must retain the following
  88  *    acknowledgment:
  89  *    "This product includes software developed by the OpenSSL Project
  90  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
  91  *
  92  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  93  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  94  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  95  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  96  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  97  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  98  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  99  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 100  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 101  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 102  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 103  * OF THE POSSIBILITY OF SUCH DAMAGE.
 104  * ====================================================================
 105  *
 106  * This product includes cryptographic software written by Eric Young
 107  * (eay@cryptsoft.com).  This product includes software written by Tim
 108  * Hudson (tjh@cryptsoft.com).
 109  *
 110  */
 111
 112 #include <stdio.h>
 113 #include <openssl/objects.h>
 114 #include <openssl/evp.h>
 115 #include <openssl/hmac.h>
 116 #include <openssl/ocsp.h>
 117 #include <openssl/rand.h>
 118 #include "ssl_locl.h"
 119
 120 const char tls1_version_str[]="TLSv1" OPENSSL_VERSION_PTEXT;
 121
 122 #ifndef OPENSSL_NO_TLSEXT
 123 static int tls_decrypt_ticket(SSL *s, const unsigned char *tick, int ticklen,
 124                                 const unsigned char *sess_id, int sesslen,
 125                                 SSL_SESSION **psess);
 126 #endif
 127
 128 SSL3_ENC_METHOD TLSv1_enc_data={
 129         tls1_enc,
 130         tls1_mac,
 131         tls1_setup_key_block,
 132         tls1_generate_master_secret,
 133         tls1_change_cipher_state,
 134         tls1_final_finish_mac,
 135         TLS1_FINISH_MAC_LENGTH,
 136         tls1_cert_verify_mac,
 137         TLS_MD_CLIENT_FINISH_CONST,TLS_MD_CLIENT_FINISH_CONST_SIZE,
 138         TLS_MD_SERVER_FINISH_CONST,TLS_MD_SERVER_FINISH_CONST_SIZE,
 139         tls1_alert_code,
 140         tls1_export_keying_material,
 141         };
 142
 143 long tls1_default_timeout(void)
 144         {
 145         /* 2 hours, the 24 hours mentioned in the TLSv1 spec
 146          * is way too long for http, the cache would over fill */
 147         return(60*60*2);
 148         }
 149
 150 int tls1_new(SSL *s)
 151         {
 152         if (!ssl3_new(s)) return(0);
 153         s->method->ssl_clear(s);
 154         return(1);
 155         }
 156
 157 void tls1_free(SSL *s)
 158         {
 159 #ifndef OPENSSL_NO_TLSEXT
 160         if (s->tlsext_session_ticket)
 161                 {
 162                 OPENSSL_free(s->tlsext_session_ticket);
 163                 }
 164 #endif /* OPENSSL_NO_TLSEXT */
 165         ssl3_free(s);
 166         }
 167
 168 void tls1_clear(SSL *s)
 169         {
 170         ssl3_clear(s);
 171         s->version = s->method->version;
 172         }
 173
 174 #ifndef OPENSSL_NO_EC
 175
 176 static int nid_list[] =
 177         {
 178                 NID_sect163k1, /* sect163k1 (1) */
 179                 NID_sect163r1, /* sect163r1 (2) */
 180                 NID_sect163r2, /* sect163r2 (3) */
 181                 NID_sect193r1, /* sect193r1 (4) */
 182                 NID_sect193r2, /* sect193r2 (5) */
 183                 NID_sect233k1, /* sect233k1 (6) */
 184                 NID_sect233r1, /* sect233r1 (7) */
 185                 NID_sect239k1, /* sect239k1 (8) */
 186                 NID_sect283k1, /* sect283k1 (9) */
 187                 NID_sect283r1, /* sect283r1 (10) */
 188                 NID_sect409k1, /* sect409k1 (11) */
 189                 NID_sect409r1, /* sect409r1 (12) */
 190                 NID_sect571k1, /* sect571k1 (13) */
 191                 NID_sect571r1, /* sect571r1 (14) */
 192                 NID_secp160k1, /* secp160k1 (15) */
 193                 NID_secp160r1, /* secp160r1 (16) */
 194                 NID_secp160r2, /* secp160r2 (17) */
 195                 NID_secp192k1, /* secp192k1 (18) */
 196                 NID_X9_62_prime192v1, /* secp192r1 (19) */
 197                 NID_secp224k1, /* secp224k1 (20) */
 198                 NID_secp224r1, /* secp224r1 (21) */
 199                 NID_secp256k1, /* secp256k1 (22) */
 200                 NID_X9_62_prime256v1, /* secp256r1 (23) */
 201                 NID_secp384r1, /* secp384r1 (24) */
 202                 NID_secp521r1  /* secp521r1 (25) */
 203         };
 204
 205 static int pref_list[] =
 206         {
 207                 NID_sect571r1, /* sect571r1 (14) */
 208                 NID_sect571k1, /* sect571k1 (13) */
 209                 NID_secp521r1, /* secp521r1 (25) */
 210                 NID_sect409k1, /* sect409k1 (11) */
 211                 NID_sect409r1, /* sect409r1 (12) */
 212                 NID_secp384r1, /* secp384r1 (24) */
 213                 NID_sect283k1, /* sect283k1 (9) */
 214                 NID_sect283r1, /* sect283r1 (10) */
 215                 NID_secp256k1, /* secp256k1 (22) */
 216                 NID_X9_62_prime256v1, /* secp256r1 (23) */
 217                 NID_sect239k1, /* sect239k1 (8) */
 218                 NID_sect233k1, /* sect233k1 (6) */
 219                 NID_sect233r1, /* sect233r1 (7) */
 220                 NID_secp224k1, /* secp224k1 (20) */
 221                 NID_secp224r1, /* secp224r1 (21) */
 222                 NID_sect193r1, /* sect193r1 (4) */
 223                 NID_sect193r2, /* sect193r2 (5) */
 224                 NID_secp192k1, /* secp192k1 (18) */
 225                 NID_X9_62_prime192v1, /* secp192r1 (19) */
 226                 NID_sect163k1, /* sect163k1 (1) */
 227                 NID_sect163r1, /* sect163r1 (2) */
 228                 NID_sect163r2, /* sect163r2 (3) */
 229                 NID_secp160k1, /* secp160k1 (15) */
 230                 NID_secp160r1, /* secp160r1 (16) */
 231                 NID_secp160r2, /* secp160r2 (17) */
 232         };
 233
 234 int tls1_ec_curve_id2nid(int curve_id)
 235         {
 236         /* ECC curves from draft-ietf-tls-ecc-12.txt (Oct. 17, 2005) */
 237         if ((curve_id < 1) || ((unsigned int)curve_id >
 238                                 sizeof(nid_list)/sizeof(nid_list[0])))
 239                 return 0;
 240         return nid_list[curve_id-1];
 241         }
 242
 243 int tls1_ec_nid2curve_id(int nid)
 244         {
 245         /* ECC curves from draft-ietf-tls-ecc-12.txt (Oct. 17, 2005) */
 246         switch (nid)
 247                 {
 248         case NID_sect163k1: /* sect163k1 (1) */
 249                 return 1;
 250         case NID_sect163r1: /* sect163r1 (2) */
 251                 return 2;
 252         case NID_sect163r2: /* sect163r2 (3) */
 253                 return 3;
 254         case NID_sect193r1: /* sect193r1 (4) */
 255                 return 4;
 256         case NID_sect193r2: /* sect193r2 (5) */
 257                 return 5;
 258         case NID_sect233k1: /* sect233k1 (6) */
 259                 return 6;
 260         case NID_sect233r1: /* sect233r1 (7) */
 261                 return 7;
 262         case NID_sect239k1: /* sect239k1 (8) */
 263                 return 8;
 264         case NID_sect283k1: /* sect283k1 (9) */
 265                 return 9;
 266         case NID_sect283r1: /* sect283r1 (10) */
 267                 return 10;
 268         case NID_sect409k1: /* sect409k1 (11) */
 269                 return 11;
 270         case NID_sect409r1: /* sect409r1 (12) */
 271                 return 12;
 272         case NID_sect571k1: /* sect571k1 (13) */
 273                 return 13;
 274         case NID_sect571r1: /* sect571r1 (14) */
 275                 return 14;
 276         case NID_secp160k1: /* secp160k1 (15) */
 277                 return 15;
 278         case NID_secp160r1: /* secp160r1 (16) */
 279                 return 16;
 280         case NID_secp160r2: /* secp160r2 (17) */
 281                 return 17;
 282         case NID_secp192k1: /* secp192k1 (18) */
 283                 return 18;
 284         case NID_X9_62_prime192v1: /* secp192r1 (19) */
 285                 return 19;
 286         case NID_secp224k1: /* secp224k1 (20) */
 287                 return 20;
 288         case NID_secp224r1: /* secp224r1 (21) */
 289                 return 21;
 290         case NID_secp256k1: /* secp256k1 (22) */
 291                 return 22;
 292         case NID_X9_62_prime256v1: /* secp256r1 (23) */
 293                 return 23;
 294         case NID_secp384r1: /* secp384r1 (24) */
 295                 return 24;
 296         case NID_secp521r1:  /* secp521r1 (25) */
 297                 return 25;
 298         default:
 299                 return 0;
 300                 }
 301         }
 302 #endif /* OPENSSL_NO_EC */
 303
 304 #ifndef OPENSSL_NO_TLSEXT
 305
 306 /* List of supported signature algorithms and hashes. Should make this
 307  * customisable at some point, for now include everything we support.
 308  */
 309
 310 #ifdef OPENSSL_NO_RSA
 311 #define tlsext_sigalg_rsa(md) /* */
 312 #else
 313 #define tlsext_sigalg_rsa(md) md, TLSEXT_signature_rsa,
 314 #endif
 315
 316 #ifdef OPENSSL_NO_DSA
 317 #define tlsext_sigalg_dsa(md) /* */
 318 #else
 319 #define tlsext_sigalg_dsa(md) md, TLSEXT_signature_dsa,
 320 #endif
 321
 322 #ifdef OPENSSL_NO_ECDSA
 323 #define tlsext_sigalg_ecdsa(md) /* */
 324 #else
 325 #define tlsext_sigalg_ecdsa(md) md, TLSEXT_signature_ecdsa,
 326 #endif
 327
 328 #define tlsext_sigalg(md) \
 329                 tlsext_sigalg_rsa(md) \
 330                 tlsext_sigalg_dsa(md) \
 331                 tlsext_sigalg_ecdsa(md)
 332
 333 static unsigned char tls12_sigalgs[] = {
 334 #ifndef OPENSSL_NO_SHA512
 335         tlsext_sigalg(TLSEXT_hash_sha512)
 336         tlsext_sigalg(TLSEXT_hash_sha384)
 337 #endif
 338 #ifndef OPENSSL_NO_SHA256
 339         tlsext_sigalg(TLSEXT_hash_sha256)
 340         tlsext_sigalg(TLSEXT_hash_sha224)
 341 #endif
 342 #ifndef OPENSSL_NO_SHA
 343         tlsext_sigalg(TLSEXT_hash_sha1)
 344 #endif
 345 };
 346
 347 int tls12_get_req_sig_algs(SSL *s, unsigned char *p)
 348         {
 349         size_t slen = sizeof(tls12_sigalgs);
 350         if (p)
 351                 memcpy(p, tls12_sigalgs, slen);
 352         return (int)slen;
 353         }
 354
 355 unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, unsigned char *limit)
 356         {
 357         int extdatalen=0;
 358         unsigned char *orig = buf;
 359         unsigned char *ret = buf;
 360
 361         /* don't add extensions for SSLv3 unless doing secure renegotiation */
 362         if (s->client_version == SSL3_VERSION
 363                                         && !s->s3->send_connection_binding)
 364                 return orig;
 365
 366         ret+=2;
 367
 368         if (ret>=limit) return NULL; /* this really never occurs, but ... */
 369
 370         if (s->tlsext_hostname != NULL)
 371                 {
 372                 /* Add TLS extension servername to the Client Hello message */
 373                 unsigned long size_str;
 374                 long lenmax;
 375
 376                 /* check for enough space.
 377                    4 for the servername type and entension length
 378                    2 for servernamelist length
 379                    1 for the hostname type
 380                    2 for hostname length
 381                    + hostname length
 382                 */
 383
 384                 if ((lenmax = limit - ret - 9) < 0
 385                     || (size_str = strlen(s->tlsext_hostname)) > (unsigned long)lenmax)
 386                         return NULL;
 387
 388                 /* extension type and length */
 389                 s2n(TLSEXT_TYPE_server_name,ret);
 390                 s2n(size_str+5,ret);
 391
 392                 /* length of servername list */
 393                 s2n(size_str+3,ret);
 394
 395                 /* hostname type, length and hostname */
 396                 *(ret++) = (unsigned char) TLSEXT_NAMETYPE_host_name;
 397                 s2n(size_str,ret);
 398                 memcpy(ret, s->tlsext_hostname, size_str);
 399                 ret+=size_str;
 400                 }
 401
 402         /* Add RI if renegotiating */
 403         if (s->renegotiate)
 404           {
 405           int el;
 406
 407           if(!ssl_add_clienthello_renegotiate_ext(s, 0, &el, 0))
 408               {
 409               SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
 410               return NULL;
 411               }
 412
 413           if((limit - ret - 4 - el) < 0) return NULL;
 414
 415           s2n(TLSEXT_TYPE_renegotiate,ret);
 416           s2n(el,ret);
 417
 418           if(!ssl_add_clienthello_renegotiate_ext(s, ret, &el, el))
 419               {
 420               SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
 421               return NULL;
 422               }
 423
 424           ret += el;
 425         }
 426
 427 #ifndef OPENSSL_NO_SRP
 428         /* Add SRP username if there is one */
 429         if (s->srp_ctx.login != NULL)
 430                 { /* Add TLS extension SRP username to the Client Hello message */
 431
 432                 int login_len = strlen(s->srp_ctx.login);
 433                 if (login_len > 255 || login_len == 0)
 434                         {
 435                         SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
 436                         return NULL;
 437                         }
 438
 439                 /* check for enough space.
 440                    4 for the srp type type and entension length
 441                    1 for the srp user identity
 442                    + srp user identity length
 443                 */
 444                 if ((limit - ret - 5 - login_len) < 0) return NULL;
 445
 446                 /* fill in the extension */
 447                 s2n(TLSEXT_TYPE_srp,ret);
 448                 s2n(login_len+1,ret);
 449                 (*ret++) = (unsigned char) login_len;
 450                 memcpy(ret, s->srp_ctx.login, login_len);
 451                 ret+=login_len;
 452                 }
 453 #endif
 454
 455 #ifndef OPENSSL_NO_EC
 456         if (s->tlsext_ecpointformatlist != NULL)
 457                 {
 458                 /* Add TLS extension ECPointFormats to the ClientHello message */
 459                 long lenmax;
 460
 461                 if ((lenmax = limit - ret - 5) < 0) return NULL;
 462                 if (s->tlsext_ecpointformatlist_length > (unsigned long)lenmax) return NULL;
 463                 if (s->tlsext_ecpointformatlist_length > 255)
 464                         {
 465                         SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
 466                         return NULL;
 467                         }
 468
 469                 s2n(TLSEXT_TYPE_ec_point_formats,ret);
 470                 s2n(s->tlsext_ecpointformatlist_length + 1,ret);
 471                 *(ret++) = (unsigned char) s->tlsext_ecpointformatlist_length;
 472                 memcpy(ret, s->tlsext_ecpointformatlist, s->tlsext_ecpointformatlist_length);
 473                 ret+=s->tlsext_ecpointformatlist_length;
 474                 }
 475         if (s->tlsext_ellipticcurvelist != NULL)
 476                 {
 477                 /* Add TLS extension EllipticCurves to the ClientHello message */
 478                 long lenmax;
 479
 480                 if ((lenmax = limit - ret - 6) < 0) return NULL;
 481                 if (s->tlsext_ellipticcurvelist_length > (unsigned long)lenmax) return NULL;
 482                 if (s->tlsext_ellipticcurvelist_length > 65532)
 483                         {
 484                         SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
 485                         return NULL;
 486                         }
 487
 488                 s2n(TLSEXT_TYPE_elliptic_curves,ret);
 489                 s2n(s->tlsext_ellipticcurvelist_length + 2, ret);
 490
 491                 /* NB: draft-ietf-tls-ecc-12.txt uses a one-byte prefix for
 492                  * elliptic_curve_list, but the examples use two bytes.
 493                  * http://www1.ietf.org/mail-archive/web/tls/current/msg00538.html
 494                  * resolves this to two bytes.
 495                  */
 496                 s2n(s->tlsext_ellipticcurvelist_length, ret);
 497                 memcpy(ret, s->tlsext_ellipticcurvelist, s->tlsext_ellipticcurvelist_length);
 498                 ret+=s->tlsext_ellipticcurvelist_length;
 499                 }
 500 #endif /* OPENSSL_NO_EC */
 501
 502         if (!(SSL_get_options(s) & SSL_OP_NO_TICKET))
 503                 {
 504                 int ticklen;
 505                 if (!s->new_session && s->session && s->session->tlsext_tick)
 506                         ticklen = s->session->tlsext_ticklen;
 507                 else if (s->session && s->tlsext_session_ticket &&
 508                          s->tlsext_session_ticket->data)
 509                         {
 510                         ticklen = s->tlsext_session_ticket->length;
 511                         s->session->tlsext_tick = OPENSSL_malloc(ticklen);
 512                         if (!s->session->tlsext_tick)
 513                                 return NULL;
 514                         memcpy(s->session->tlsext_tick,
 515                                s->tlsext_session_ticket->data,
 516                                ticklen);
 517                         s->session->tlsext_ticklen = ticklen;
 518                         }
 519                 else
 520                         ticklen = 0;
 521                 if (ticklen == 0 && s->tlsext_session_ticket &&
 522                     s->tlsext_session_ticket->data == NULL)
 523                         goto skip_ext;
 524                 /* Check for enough room 2 for extension type, 2 for len
 525                  * rest for ticket
 526                  */
 527                 if ((long)(limit - ret - 4 - ticklen) < 0) return NULL;
 528                 s2n(TLSEXT_TYPE_session_ticket,ret);
 529                 s2n(ticklen,ret);
 530                 if (ticklen)
 531                         {
 532                         memcpy(ret, s->session->tlsext_tick, ticklen);
 533                         ret += ticklen;
 534                         }
 535                 }
 536                 skip_ext:
 537
 538         if (TLS1_get_client_version(s) >= TLS1_2_VERSION)
 539                 {
 540                 if ((size_t)(limit - ret) < sizeof(tls12_sigalgs) + 6)
 541                         return NULL;
 542                 s2n(TLSEXT_TYPE_signature_algorithms,ret);
 543                 s2n(sizeof(tls12_sigalgs) + 2, ret);
 544                 s2n(sizeof(tls12_sigalgs), ret);
 545                 memcpy(ret, tls12_sigalgs, sizeof(tls12_sigalgs));
 546                 ret += sizeof(tls12_sigalgs);
 547                 }
 548
 549 #ifdef TLSEXT_TYPE_opaque_prf_input
 550         if (s->s3->client_opaque_prf_input != NULL &&
 551             s->version != DTLS1_VERSION)
 552                 {
 553                 size_t col = s->s3->client_opaque_prf_input_len;
 554
 555                 if ((long)(limit - ret - 6 - col < 0))
 556                         return NULL;
 557                 if (col > 0xFFFD) /* can't happen */
 558                         return NULL;
 559
 560                 s2n(TLSEXT_TYPE_opaque_prf_input, ret);
 561                 s2n(col + 2, ret);
 562                 s2n(col, ret);
 563                 memcpy(ret, s->s3->client_opaque_prf_input, col);
 564                 ret += col;
 565                 }
 566 #endif
 567
 568         if (s->tlsext_status_type == TLSEXT_STATUSTYPE_ocsp &&
 569             s->version != DTLS1_VERSION)
 570                 {
 571                 int i;
 572                 long extlen, idlen, itmp;
 573                 OCSP_RESPID *id;
 574
 575                 idlen = 0;
 576                 for (i = 0; i < sk_OCSP_RESPID_num(s->tlsext_ocsp_ids); i++)
 577                         {
 578                         id = sk_OCSP_RESPID_value(s->tlsext_ocsp_ids, i);
 579                         itmp = i2d_OCSP_RESPID(id, NULL);
 580                         if (itmp <= 0)
 581                                 return NULL;
 582                         idlen += itmp + 2;
 583                         }
 584
 585                 if (s->tlsext_ocsp_exts)
 586                         {
 587                         extlen = i2d_X509_EXTENSIONS(s->tlsext_ocsp_exts, NULL);
 588                         if (extlen < 0)
 589                                 return NULL;
 590                         }
 591                 else
 592                         extlen = 0;
 593
 594                 if ((long)(limit - ret - 7 - extlen - idlen) < 0) return NULL;
 595                 s2n(TLSEXT_TYPE_status_request, ret);
 596                 if (extlen + idlen > 0xFFF0)
 597                         return NULL;
 598                 s2n(extlen + idlen + 5, ret);
 599                 *(ret++) = TLSEXT_STATUSTYPE_ocsp;
 600                 s2n(idlen, ret);
 601                 for (i = 0; i < sk_OCSP_RESPID_num(s->tlsext_ocsp_ids); i++)
 602                         {
 603                         /* save position of id len */
 604                         unsigned char *q = ret;
 605                         id = sk_OCSP_RESPID_value(s->tlsext_ocsp_ids, i);
 606                         /* skip over id len */
 607                         ret += 2;
 608                         itmp = i2d_OCSP_RESPID(id, &ret);
 609                         /* write id len */
 610                         s2n(itmp, q);
 611                         }
 612                 s2n(extlen, ret);
 613                 if (extlen > 0)
 614                         i2d_X509_EXTENSIONS(s->tlsext_ocsp_exts, &ret);
 615                 }
 616
 617 #ifndef OPENSSL_NO_HEARTBEATS
 618         /* Add Heartbeat extension */
 619         if ((limit - ret - 4 - 1) < 0)
 620                 return NULL;
 621         s2n(TLSEXT_TYPE_heartbeat,ret);
 622         s2n(1,ret);
 623         /* Set mode:
 624          * 1: peer may send requests
 625          * 2: peer not allowed to send requests
 626          */
 627         if (s->tlsext_heartbeat & SSL_TLSEXT_HB_DONT_RECV_REQUESTS)
 628                 *(ret++) = SSL_TLSEXT_HB_DONT_SEND_REQUESTS;
 629         else
 630                 *(ret++) = SSL_TLSEXT_HB_ENABLED;
 631 #endif
 632
 633 #ifndef OPENSSL_NO_NEXTPROTONEG
 634         if (s->ctx->next_proto_select_cb && !s->s3->tmp.finish_md_len)
 635                 {
 636                 /* The client advertises an emtpy extension to indicate its
 637                  * support for Next Protocol Negotiation */
 638                 if (limit - ret - 4 < 0)
 639                         return NULL;
 640                 s2n(TLSEXT_TYPE_next_proto_neg,ret);
 641                 s2n(0,ret);
 642                 }
 643 #endif
 644
 645 #ifndef OPENSSL_NO_SRTP
 646         if(SSL_IS_DTLS(s) && SSL_get_srtp_profiles(s))
 647                 {
 648                 int el;
 649
 650                 ssl_add_clienthello_use_srtp_ext(s, 0, &el, 0);
 651
 652                 if((limit - ret - 4 - el) < 0) return NULL;
 653
 654                 s2n(TLSEXT_TYPE_use_srtp,ret);
 655                 s2n(el,ret);
 656
 657                 if(ssl_add_clienthello_use_srtp_ext(s, ret, &el, el))
 658                         {
 659                         SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
 660                         return NULL;
 661                         }
 662                 ret += el;
 663                 }
 664 #endif
 665         /* Add padding to workaround bugs in F5 terminators.
 666          * See https://tools.ietf.org/html/draft-agl-tls-padding-03
 667          *
 668          * NB: because this code works out the length of all existing
 669          * extensions it MUST always appear last.
 670          */
 671         if (s->options & SSL_OP_TLSEXT_PADDING)
 672                 {
 673                 int hlen = ret - (unsigned char *)s->init_buf->data;
 674                 /* The code in s23_clnt.c to build ClientHello messages
 675                  * includes the 5-byte record header in the buffer, while
 676                  * the code in s3_clnt.c does not.
 677                  */
 678                 if (s->state == SSL23_ST_CW_CLNT_HELLO_A)
 679                         hlen -= 5;
 680                 if (hlen > 0xff && hlen < 0x200)
 681                         {
 682                         hlen = 0x200 - hlen;
 683                         if (hlen >= 4)
 684                                 hlen -= 4;
 685                         else
 686                                 hlen = 0;
 687
 688                         s2n(TLSEXT_TYPE_padding, ret);
 689                         s2n(hlen, ret);
 690                         memset(ret, 0, hlen);
 691                         ret += hlen;
 692                         }
 693                 }
 694
 695         if ((extdatalen = ret-orig-2)== 0)
 696                 return orig;
 697
 698         s2n(extdatalen, orig);
 699         return ret;
 700         }
 701
 702 unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, unsigned char *limit)
 703         {
 704         int extdatalen=0;
 705         unsigned char *orig = buf;
 706         unsigned char *ret = buf;
 707 #ifndef OPENSSL_NO_NEXTPROTONEG
 708         int next_proto_neg_seen;
 709 #endif
 710
 711         /* don't add extensions for SSLv3, unless doing secure renegotiation */
 712         if (s->version == SSL3_VERSION && !s->s3->send_connection_binding)
 713                 return orig;
 714
 715         ret+=2;
 716         if (ret>=limit) return NULL; /* this really never occurs, but ... */
 717
 718         if (!s->hit && s->servername_done == 1 && s->session->tlsext_hostname != NULL)
 719                 {
 720                 if ((long)(limit - ret - 4) < 0) return NULL;
 721
 722                 s2n(TLSEXT_TYPE_server_name,ret);
 723                 s2n(0,ret);
 724                 }
 725
 726         if(s->s3->send_connection_binding)
 727         {
 728           int el;
 729
 730           if(!ssl_add_serverhello_renegotiate_ext(s, 0, &el, 0))
 731               {
 732               SSLerr(SSL_F_SSL_ADD_SERVERHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
 733               return NULL;
 734               }
 735
 736           if((limit - ret - 4 - el) < 0) return NULL;
 737
 738           s2n(TLSEXT_TYPE_renegotiate,ret);
 739           s2n(el,ret);
 740
 741           if(!ssl_add_serverhello_renegotiate_ext(s, ret, &el, el))
 742               {
 743               SSLerr(SSL_F_SSL_ADD_SERVERHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
 744               return NULL;
 745               }
 746
 747           ret += el;
 748         }
 749
 750 #ifndef OPENSSL_NO_EC
 751         if (s->tlsext_ecpointformatlist != NULL)
 752                 {
 753                 /* Add TLS extension ECPointFormats to the ServerHello message */
 754                 long lenmax;
 755
 756                 if ((lenmax = limit - ret - 5) < 0) return NULL;
 757                 if (s->tlsext_ecpointformatlist_length > (unsigned long)lenmax) return NULL;
 758                 if (s->tlsext_ecpointformatlist_length > 255)
 759                         {
 760                         SSLerr(SSL_F_SSL_ADD_SERVERHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
 761                         return NULL;
 762                         }
 763
 764                 s2n(TLSEXT_TYPE_ec_point_formats,ret);
 765                 s2n(s->tlsext_ecpointformatlist_length + 1,ret);
 766                 *(ret++) = (unsigned char) s->tlsext_ecpointformatlist_length;
 767                 memcpy(ret, s->tlsext_ecpointformatlist, s->tlsext_ecpointformatlist_length);
 768                 ret+=s->tlsext_ecpointformatlist_length;
 769
 770                 }
 771         /* Currently the server should not respond with a SupportedCurves extension */
 772 #endif /* OPENSSL_NO_EC */
 773
 774         if (s->tlsext_ticket_expected
 775                 && !(SSL_get_options(s) & SSL_OP_NO_TICKET))
 776                 {
 777                 if ((long)(limit - ret - 4) < 0) return NULL;
 778                 s2n(TLSEXT_TYPE_session_ticket,ret);
 779                 s2n(0,ret);
 780                 }
 781
 782         if (s->tlsext_status_expected)
 783                 {
 784                 if ((long)(limit - ret - 4) < 0) return NULL;
 785                 s2n(TLSEXT_TYPE_status_request,ret);
 786                 s2n(0,ret);
 787                 }
 788
 789 #ifdef TLSEXT_TYPE_opaque_prf_input
 790         if (s->s3->server_opaque_prf_input != NULL &&
 791             s->version != DTLS1_VERSION)
 792                 {
 793                 size_t sol = s->s3->server_opaque_prf_input_len;
 794
 795                 if ((long)(limit - ret - 6 - sol) < 0)
 796                         return NULL;
 797                 if (sol > 0xFFFD) /* can't happen */
 798                         return NULL;
 799
 800                 s2n(TLSEXT_TYPE_opaque_prf_input, ret);
 801                 s2n(sol + 2, ret);
 802                 s2n(sol, ret);
 803                 memcpy(ret, s->s3->server_opaque_prf_input, sol);
 804                 ret += sol;
 805                 }
 806 #endif
 807
 808 #ifndef OPENSSL_NO_SRTP
 809         if(SSL_IS_DTLS(s) && s->srtp_profile)
 810                 {
 811                 int el;
 812
 813                 ssl_add_serverhello_use_srtp_ext(s, 0, &el, 0);
 814
 815                 if((limit - ret - 4 - el) < 0) return NULL;
 816
 817                 s2n(TLSEXT_TYPE_use_srtp,ret);
 818                 s2n(el,ret);
 819
 820                 if(ssl_add_serverhello_use_srtp_ext(s, ret, &el, el))
 821                         {
 822                         SSLerr(SSL_F_SSL_ADD_SERVERHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
 823                         return NULL;
 824                         }
 825                 ret+=el;
 826                 }
 827 #endif
 828
 829         if (((s->s3->tmp.new_cipher->id & 0xFFFF)==0x80 || (s->s3->tmp.new_cipher->id & 0xFFFF)==0x81)
 830                 && (SSL_get_options(s) & SSL_OP_CRYPTOPRO_TLSEXT_BUG))
 831                 { const unsigned char cryptopro_ext[36] = {
 832                         0xfd, 0xe8, /*65000*/
 833                         0x00, 0x20, /*32 bytes length*/
 834                         0x30, 0x1e, 0x30, 0x08, 0x06, 0x06, 0x2a, 0x85,
 835                         0x03,   0x02, 0x02, 0x09, 0x30, 0x08, 0x06, 0x06,
 836                         0x2a, 0x85, 0x03, 0x02, 0x02, 0x16, 0x30, 0x08,
 837                         0x06, 0x06, 0x2a, 0x85, 0x03, 0x02, 0x02, 0x17};
 838                         if (limit-ret<36) return NULL;
 839                         memcpy(ret,cryptopro_ext,36);
 840                         ret+=36;
 841
 842                 }
 843
 844 #ifndef OPENSSL_NO_HEARTBEATS
 845         /* Add Heartbeat extension if we've received one */
 846         if (s->tlsext_heartbeat & SSL_TLSEXT_HB_ENABLED)
 847                 {
 848                 if ((limit - ret - 4 - 1) < 0)
 849                         return NULL;
 850                 s2n(TLSEXT_TYPE_heartbeat,ret);
 851                 s2n(1,ret);
 852                 /* Set mode:
 853                  * 1: peer may send requests
 854                  * 2: peer not allowed to send requests
 855                  */
 856                 if (s->tlsext_heartbeat & SSL_TLSEXT_HB_DONT_RECV_REQUESTS)
 857                         *(ret++) = SSL_TLSEXT_HB_DONT_SEND_REQUESTS;
 858                 else
 859                         *(ret++) = SSL_TLSEXT_HB_ENABLED;
 860
 861                 }
 862 #endif
 863
 864 #ifndef OPENSSL_NO_NEXTPROTONEG
 865         next_proto_neg_seen = s->s3->next_proto_neg_seen;
 866         s->s3->next_proto_neg_seen = 0;
 867         if (next_proto_neg_seen && s->ctx->next_protos_advertised_cb)
 868                 {
 869                 const unsigned char *npa;
 870                 unsigned int npalen;
 871                 int r;
 872
 873                 r = s->ctx->next_protos_advertised_cb(s, &npa, &npalen, s->ctx->next_protos_advertised_cb_arg);
 874                 if (r == SSL_TLSEXT_ERR_OK)
 875                         {
 876                         if ((long)(limit - ret - 4 - npalen) < 0) return NULL;
 877                         s2n(TLSEXT_TYPE_next_proto_neg,ret);
 878                         s2n(npalen,ret);
 879                         memcpy(ret, npa, npalen);
 880                         ret += npalen;
 881                         s->s3->next_proto_neg_seen = 1;
 882                         }
 883                 }
 884 #endif
 885
 886         if ((extdatalen = ret-orig-2)== 0)
 887                 return orig;
 888
 889         s2n(extdatalen, orig);
 890         return ret;
 891         }
 892
 893 #ifndef OPENSSL_NO_EC
 894 /* ssl_check_for_safari attempts to fingerprint Safari using OS X
 895  * SecureTransport using the TLS extension block in |d|, of length |n|.
 896  * Safari, since 10.6, sends exactly these extensions, in this order:
 897  *   SNI,
 898  *   elliptic_curves
 899  *   ec_point_formats
 900  *
 901  * We wish to fingerprint Safari because they broke ECDHE-ECDSA support in 10.8,
 902  * but they advertise support. So enabling ECDHE-ECDSA ciphers breaks them.
 903  * Sadly we cannot differentiate 10.6, 10.7 and 10.8.4 (which work), from
 904  * 10.8..10.8.3 (which don't work).
 905  */
 906 static void ssl_check_for_safari(SSL *s, const unsigned char *data, const unsigned char *d, int n) {
 907         unsigned short type, size;
 908         static const unsigned char kSafariExtensionsBlock[] = {
 909                 0x00, 0x0a,  /* elliptic_curves extension */
 910                 0x00, 0x08,  /* 8 bytes */
 911                 0x00, 0x06,  /* 6 bytes of curve ids */
 912                 0x00, 0x17,  /* P-256 */
 913                 0x00, 0x18,  /* P-384 */
 914                 0x00, 0x19,  /* P-521 */
 915
 916                 0x00, 0x0b,  /* ec_point_formats */
 917                 0x00, 0x02,  /* 2 bytes */
 918                 0x01,        /* 1 point format */
 919                 0x00,        /* uncompressed */
 920         };
 921
 922         /* The following is only present in TLS 1.2 */
 923         static const unsigned char kSafariTLS12ExtensionsBlock[] = {
 924                 0x00, 0x0d,  /* signature_algorithms */
 925                 0x00, 0x0c,  /* 12 bytes */
 926                 0x00, 0x0a,  /* 10 bytes */
 927                 0x05, 0x01,  /* SHA-384/RSA */
 928                 0x04, 0x01,  /* SHA-256/RSA */
 929                 0x02, 0x01,  /* SHA-1/RSA */
 930                 0x04, 0x03,  /* SHA-256/ECDSA */
 931                 0x02, 0x03,  /* SHA-1/ECDSA */
 932         };
 933
 934         if (data >= (d+n-2))
 935                 return;
 936         data += 2;
 937
 938         if (data > (d+n-4))
 939                 return;
 940         n2s(data,type);
 941         n2s(data,size);
 942
 943         if (type != TLSEXT_TYPE_server_name)
 944                 return;
 945
 946         if (data+size > d+n)
 947                 return;
 948         data += size;
 949
 950         if (TLS1_get_client_version(s) >= TLS1_2_VERSION)
 951                 {
 952                 const size_t len1 = sizeof(kSafariExtensionsBlock);
 953                 const size_t len2 = sizeof(kSafariTLS12ExtensionsBlock);
 954
 955                 if (data + len1 + len2 != d+n)
 956                         return;
 957                 if (memcmp(data, kSafariExtensionsBlock, len1) != 0)
 958                         return;
 959                 if (memcmp(data + len1, kSafariTLS12ExtensionsBlock, len2) != 0)
 960                         return;
 961                 }
 962         else
 963                 {
 964                 const size_t len = sizeof(kSafariExtensionsBlock);
 965
 966                 if (data + len != d+n)
 967                         return;
 968                 if (memcmp(data, kSafariExtensionsBlock, len) != 0)
 969                         return;
 970                 }
 971
 972         s->s3->is_probably_safari = 1;
 973 }
 974 #endif /* !OPENSSL_NO_EC */
 975
 976 int ssl_parse_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char *d, int n, int *al)
 977         {
 978         unsigned short type;
 979         unsigned short size;
 980         unsigned short len;
 981         unsigned char *data = *p;
 982         int renegotiate_seen = 0;
 983         int sigalg_seen = 0;
 984
 985         s->servername_done = 0;
 986         s->tlsext_status_type = -1;
 987 #ifndef OPENSSL_NO_NEXTPROTONEG
 988         s->s3->next_proto_neg_seen = 0;
 989 #endif
 990
 991 #ifndef OPENSSL_NO_HEARTBEATS
 992         s->tlsext_heartbeat &= ~(SSL_TLSEXT_HB_ENABLED |
 993                                SSL_TLSEXT_HB_DONT_SEND_REQUESTS);
 994 #endif
 995
 996 #ifndef OPENSSL_NO_EC
 997         if (s->options & SSL_OP_SAFARI_ECDHE_ECDSA_BUG)
 998                 ssl_check_for_safari(s, data, d, n);
 999 #endif /* !OPENSSL_NO_EC */
1000
1001         if (data >= (d+n-2))
1002                 goto ri_check;
1003         n2s(data,len);
1004
1005         if (data > (d+n-len))
1006                 goto ri_check;
1007
1008         while (data <= (d+n-4))
1009                 {
1010                 n2s(data,type);
1011                 n2s(data,size);
1012
1013                 if (data+size > (d+n))
1014                         goto ri_check;
1015 #if 0
1016                 fprintf(stderr,"Received extension type %d size %d\n",type,size);
1017 #endif
1018                 if (s->tlsext_debug_cb)
1019                         s->tlsext_debug_cb(s, 0, type, data, size,
1020                                                 s->tlsext_debug_arg);
1021 /* The servername extension is treated as follows:
1022
1023    - Only the hostname type is supported with a maximum length of 255.
1024    - The servername is rejected if too long or if it contains zeros,
1025      in which case an fatal alert is generated.
1026    - The servername field is maintained together with the session cache.
1027    - When a session is resumed, the servername call back invoked in order
1028      to allow the application to position itself to the right context.
1029    - The servername is acknowledged if it is new for a session or when
1030      it is identical to a previously used for the same session.
1031      Applications can control the behaviour.  They can at any time
1032      set a 'desirable' servername for a new SSL object. This can be the
1033      case for example with HTTPS when a Host: header field is received and
1034      a renegotiation is requested. In this case, a possible servername
1035      presented in the new client hello is only acknowledged if it matches
1036      the value of the Host: field.
1037    - Applications must  use SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION
1038      if they provide for changing an explicit servername context for the session,
1039      i.e. when the session has been established with a servername extension.
1040    - On session reconnect, the servername extension may be absent.
1041
1042 */
1043
1044                 if (type == TLSEXT_TYPE_server_name)
1045                         {
1046                         unsigned char *sdata;
1047                         int servname_type;
1048                         int dsize;
1049
1050                         if (size < 2)
1051                                 {
1052                                 *al = SSL_AD_DECODE_ERROR;
1053                                 return 0;
1054                                 }
1055                         n2s(data,dsize);
1056                         size -= 2;
1057                         if (dsize > size  )
1058                                 {
1059                                 *al = SSL_AD_DECODE_ERROR;
1060                                 return 0;
1061                                 }
1062
1063                         sdata = data;
1064                         while (dsize > 3)
1065                                 {
1066                                 servname_type = *(sdata++);
1067                                 n2s(sdata,len);
1068                                 dsize -= 3;
1069
1070                                 if (len > dsize)
1071                                         {
1072                                         *al = SSL_AD_DECODE_ERROR;
1073                                         return 0;
1074                                         }
1075                                 if (s->servername_done == 0)
1076                                 switch (servname_type)
1077                                         {
1078                                 case TLSEXT_NAMETYPE_host_name:
1079                                         if (!s->hit)
1080                                                 {
1081                                                 if(s->session->tlsext_hostname)
1082                                                         {
1083                                                         *al = SSL_AD_DECODE_ERROR;
1084                                                         return 0;
1085                                                         }
1086                                                 if (len > TLSEXT_MAXLEN_host_name)
1087                                                         {
1088                                                         *al = TLS1_AD_UNRECOGNIZED_NAME;
1089                                                         return 0;
1090                                                         }
1091                                                 if ((s->session->tlsext_hostname = OPENSSL_malloc(len+1)) == NULL)
1092                                                         {
1093                                                         *al = TLS1_AD_INTERNAL_ERROR;
1094                                                         return 0;
1095                                                         }
1096                                                 memcpy(s->session->tlsext_hostname, sdata, len);
1097                                                 s->session->tlsext_hostname[len]='\0';
1098                                                 if (strlen(s->session->tlsext_hostname) != len) {
1099                                                         OPENSSL_free(s->session->tlsext_hostname);
1100                                                         s->session->tlsext_hostname = NULL;
1101                                                         *al = TLS1_AD_UNRECOGNIZED_NAME;
1102                                                         return 0;
1103                                                 }
1104                                                 s->servername_done = 1;
1105
1106                                                 }
1107                                         else
1108                                                 s->servername_done = s->session->tlsext_hostname
1109                                                         && strlen(s->session->tlsext_hostname) == len
1110                                                         && strncmp(s->session->tlsext_hostname, (char *)sdata, len) == 0;
1111
1112                                         break;
1113
1114                                 default:
1115                                         break;
1116                                         }
1117
1118                                 dsize -= len;
1119                                 }
1120                         if (dsize != 0)
1121                                 {
1122                                 *al = SSL_AD_DECODE_ERROR;
1123                                 return 0;
1124                                 }
1125
1126                         }
1127 #ifndef OPENSSL_NO_SRP
1128                 else if (type == TLSEXT_TYPE_srp)
1129                         {
1130                         if (size <= 0 || ((len = data[0])) != (size -1))
1131                                 {
1132                                 *al = SSL_AD_DECODE_ERROR;
1133                                 return 0;
1134                                 }
1135                         if (s->srp_ctx.login != NULL)
1136                                 {
1137                                 *al = SSL_AD_DECODE_ERROR;
1138                                 return 0;
1139                                 }
1140                         if ((s->srp_ctx.login = OPENSSL_malloc(len+1)) == NULL)
1141                                 return -1;
1142                         memcpy(s->srp_ctx.login, &data[1], len);
1143                         s->srp_ctx.login[len]='\0';
1144
1145                         if (strlen(s->srp_ctx.login) != len)
1146                                 {
1147                                 *al = SSL_AD_DECODE_ERROR;
1148                                 return 0;
1149                                 }
1150                         }
1151 #endif
1152
1153 #ifndef OPENSSL_NO_EC
1154                 else if (type == TLSEXT_TYPE_ec_point_formats)
1155                         {
1156                         unsigned char *sdata = data;
1157                         int ecpointformatlist_length = *(sdata++);
1158
1159                         if (ecpointformatlist_length != size - 1)
1160                                 {
1161                                 *al = TLS1_AD_DECODE_ERROR;
1162                                 return 0;
1163                                 }
1164                         if (!s->hit)
1165                                 {
1166                                 if(s->session->tlsext_ecpointformatlist)
1167                                         {
1168                                         OPENSSL_free(s->session->tlsext_ecpointformatlist);
1169                                         s->session->tlsext_ecpointformatlist = NULL;
1170                                         }
1171                                 s->session->tlsext_ecpointformatlist_length = 0;
1172                                 if ((s->session->tlsext_ecpointformatlist = OPENSSL_malloc(ecpointformatlist_length)) == NULL)
1173                                         {
1174                                         *al = TLS1_AD_INTERNAL_ERROR;
1175                                         return 0;
1176                                         }
1177                                 s->session->tlsext_ecpointformatlist_length = ecpointformatlist_length;
1178                                 memcpy(s->session->tlsext_ecpointformatlist, sdata, ecpointformatlist_length);
1179                                 }
1180 #if 0
1181                         fprintf(stderr,"ssl_parse_clienthello_tlsext s->session->tlsext_ecpointformatlist (length=%i) ", s->session->tlsext_ecpointformatlist_length);
1182                         sdata = s->session->tlsext_ecpointformatlist;
1183                         for (i = 0; i < s->session->tlsext_ecpointformatlist_length; i++)
1184                                 fprintf(stderr,"%i ",*(sdata++));
1185                         fprintf(stderr,"\n");
1186 #endif
1187                         }
1188                 else if (type == TLSEXT_TYPE_elliptic_curves)
1189                         {
1190                         unsigned char *sdata = data;
1191                         int ellipticcurvelist_length = (*(sdata++) << 8);
1192                         ellipticcurvelist_length += (*(sdata++));
1193
1194                         if (ellipticcurvelist_length != size - 2 ||
1195                                 ellipticcurvelist_length < 1)
1196                                 {
1197                                 *al = TLS1_AD_DECODE_ERROR;
1198                                 return 0;
1199                                 }
1200                         if (!s->hit)
1201                                 {
1202                                 if(s->session->tlsext_ellipticcurvelist)
1203                                         {
1204                                         *al = TLS1_AD_DECODE_ERROR;
1205                                         return 0;
1206                                         }
1207                                 s->session->tlsext_ellipticcurvelist_length = 0;
1208                                 if ((s->session->tlsext_ellipticcurvelist = OPENSSL_malloc(ellipticcurvelist_length)) == NULL)
1209                                         {
1210                                         *al = TLS1_AD_INTERNAL_ERROR;
1211                                         return 0;
1212                                         }
1213                                 s->session->tlsext_ellipticcurvelist_length = ellipticcurvelist_length;
1214                                 memcpy(s->session->tlsext_ellipticcurvelist, sdata, ellipticcurvelist_length);
1215                                 }
1216 #if 0
1217                         fprintf(stderr,"ssl_parse_clienthello_tlsext s->session->tlsext_ellipticcurvelist (length=%i) ", s->session->tlsext_ellipticcurvelist_length);
1218                         sdata = s->session->tlsext_ellipticcurvelist;
1219                         for (i = 0; i < s->session->tlsext_ellipticcurvelist_length; i++)
1220                                 fprintf(stderr,"%i ",*(sdata++));
1221                         fprintf(stderr,"\n");
1222 #endif
1223                         }
1224 #endif /* OPENSSL_NO_EC */
1225 #ifdef TLSEXT_TYPE_opaque_prf_input
1226                 else if (type == TLSEXT_TYPE_opaque_prf_input &&
1227                      s->version != DTLS1_VERSION)
1228                         {
1229                         unsigned char *sdata = data;
1230
1231                         if (size < 2)
1232                                 {
1233                                 *al = SSL_AD_DECODE_ERROR;
1234                                 return 0;
1235                                 }
1236                         n2s(sdata, s->s3->client_opaque_prf_input_len);
1237                         if (s->s3->client_opaque_prf_input_len != size - 2)
1238                                 {
1239                                 *al = SSL_AD_DECODE_ERROR;
1240                                 return 0;
1241                                 }
1242
1243                         if (s->s3->client_opaque_prf_input != NULL) /* shouldn't really happen */
1244                                 OPENSSL_free(s->s3->client_opaque_prf_input);
1245                         if (s->s3->client_opaque_prf_input_len == 0)
1246                                 s->s3->client_opaque_prf_input = OPENSSL_malloc(1); /* dummy byte just to get non-NULL */
1247                         else
1248                                 s->s3->client_opaque_prf_input = BUF_memdup(sdata, s->s3->client_opaque_prf_input_len);
1249                         if (s->s3->client_opaque_prf_input == NULL)
1250                                 {
1251                                 *al = TLS1_AD_INTERNAL_ERROR;
1252                                 return 0;
1253                                 }
1254                         }
1255 #endif
1256                 else if (type == TLSEXT_TYPE_session_ticket)
1257                         {
1258                         if (s->tls_session_ticket_ext_cb &&
1259                             !s->tls_session_ticket_ext_cb(s, data, size, s->tls_session_ticket_ext_cb_arg))
1260                                 {
1261                                 *al = TLS1_AD_INTERNAL_ERROR;
1262                                 return 0;
1263                                 }
1264                         }
1265                 else if (type == TLSEXT_TYPE_renegotiate)
1266                         {
1267                         if(!ssl_parse_clienthello_renegotiate_ext(s, data, size, al))
1268                                 return 0;
1269                         renegotiate_seen = 1;
1270                         }
1271                 else if (type == TLSEXT_TYPE_signature_algorithms)
1272                         {
1273                         int dsize;
1274                         if (sigalg_seen || size < 2)
1275                                 {
1276                                 *al = SSL_AD_DECODE_ERROR;
1277                                 return 0;
1278                                 }
1279                         sigalg_seen = 1;
1280                         n2s(data,dsize);
1281                         size -= 2;
1282                         if (dsize != size || dsize & 1)
1283                                 {
1284                                 *al = SSL_AD_DECODE_ERROR;
1285                                 return 0;
1286                                 }
1287                         if (!tls1_process_sigalgs(s, data, dsize))
1288                                 {
1289                                 *al = SSL_AD_DECODE_ERROR;
1290                                 return 0;
1291                                 }
1292                         }
1293                 else if (type == TLSEXT_TYPE_status_request &&
1294                          s->version != DTLS1_VERSION)
1295                         {
1296
1297                         if (size < 5)
1298                                 {
1299                                 *al = SSL_AD_DECODE_ERROR;
1300                                 return 0;
1301                                 }
1302
1303                         s->tlsext_status_type = *data++;
1304                         size--;
1305                         if (s->tlsext_status_type == TLSEXT_STATUSTYPE_ocsp)
1306                                 {
1307                                 const unsigned char *sdata;
1308                                 int dsize;
1309                                 /* Read in responder_id_list */
1310                                 n2s(data,dsize);
1311                                 size -= 2;
1312                                 if (dsize > size  )
1313                                         {
1314                                         *al = SSL_AD_DECODE_ERROR;
1315                                         return 0;
1316                                         }
1317                                 while (dsize > 0)
1318                                         {
1319                                         OCSP_RESPID *id;
1320                                         int idsize;
1321                                         if (dsize < 4)
1322                                                 {
1323                                                 *al = SSL_AD_DECODE_ERROR;
1324                                                 return 0;
1325                                                 }
1326                                         n2s(data, idsize);
1327                                         dsize -= 2 + idsize;
1328                                         size -= 2 + idsize;
1329                                         if (dsize < 0)
1330                                                 {
1331                                                 *al = SSL_AD_DECODE_ERROR;
1332                                                 return 0;
1333                                                 }
1334                                         sdata = data;
1335                                         data += idsize;
1336                                         id = d2i_OCSP_RESPID(NULL,
1337                                                                 &sdata, idsize);
1338                                         if (!id)
1339                                                 {
1340                                                 *al = SSL_AD_DECODE_ERROR;
1341                                                 return 0;
1342                                                 }
1343                                         if (data != sdata)
1344                                                 {
1345                                                 OCSP_RESPID_free(id);
1346                                                 *al = SSL_AD_DECODE_ERROR;
1347                                                 return 0;
1348                                                 }
1349                                         if (!s->tlsext_ocsp_ids
1350                                                 && !(s->tlsext_ocsp_ids =
1351                                                 sk_OCSP_RESPID_new_null()))
1352                                                 {
1353                                                 OCSP_RESPID_free(id);
1354                                                 *al = SSL_AD_INTERNAL_ERROR;
1355                                                 return 0;
1356                                                 }
1357                                         if (!sk_OCSP_RESPID_push(
1358                                                         s->tlsext_ocsp_ids, id))
1359                                                 {
1360                                                 OCSP_RESPID_free(id);
1361                                                 *al = SSL_AD_INTERNAL_ERROR;
1362                                                 return 0;
1363                                                 }
1364                                         }
1365
1366                                 /* Read in request_extensions */
1367                                 if (size < 2)
1368                                         {
1369                                         *al = SSL_AD_DECODE_ERROR;
1370                                         return 0;
1371                                         }
1372                                 n2s(data,dsize);
1373                                 size -= 2;
1374                                 if (dsize != size)
1375                                         {
1376                                         *al = SSL_AD_DECODE_ERROR;
1377                                         return 0;
1378                                         }
1379                                 sdata = data;
1380                                 if (dsize > 0)
1381                                         {
1382                                         if (s->tlsext_ocsp_exts)
1383                                                 {
1384                                                 sk_X509_EXTENSION_pop_free(s->tlsext_ocsp_exts,
1385                                                                            X509_EXTENSION_free);
1386                                                 }
1387
1388                                         s->tlsext_ocsp_exts =
1389                                                 d2i_X509_EXTENSIONS(NULL,
1390                                                         &sdata, dsize);
1391                                         if (!s->tlsext_ocsp_exts
1392                                                 || (data + dsize != sdata))
1393                                                 {
1394                                                 *al = SSL_AD_DECODE_ERROR;
1395                                                 return 0;
1396                                                 }
1397                                         }
1398                                 }
1399                                 /* We don't know what to do with any other type
1400                                 * so ignore it.
1401                                 */
1402                                 else
1403                                         s->tlsext_status_type = -1;
1404                         }
1405 #ifndef OPENSSL_NO_HEARTBEATS
1406                 else if (type == TLSEXT_TYPE_heartbeat)
1407                         {
1408                         switch(data[0])
1409                                 {
1410                                 case 0x01:      /* Client allows us to send HB requests */
1411                                                         s->tlsext_heartbeat |= SSL_TLSEXT_HB_ENABLED;
1412                                                         break;
1413                                 case 0x02:      /* Client doesn't accept HB requests */
1414                                                         s->tlsext_heartbeat |= SSL_TLSEXT_HB_ENABLED;
1415                                                         s->tlsext_heartbeat |= SSL_TLSEXT_HB_DONT_SEND_REQUESTS;
1416                                                         break;
1417                                 default:        *al = SSL_AD_ILLEGAL_PARAMETER;
1418                                                         return 0;
1419                                 }
1420                         }
1421 #endif
1422 #ifndef OPENSSL_NO_NEXTPROTONEG
1423                 else if (type == TLSEXT_TYPE_next_proto_neg &&
1424                          s->s3->tmp.finish_md_len == 0)
1425                         {
1426                         /* We shouldn't accept this extension on a
1427                          * renegotiation.
1428                          *
1429                          * s->new_session will be set on renegotiation, but we
1430                          * probably shouldn't rely that it couldn't be set on
1431                          * the initial renegotation too in certain cases (when
1432                          * there's some other reason to disallow resuming an
1433                          * earlier session -- the current code won't be doing
1434                          * anything like that, but this might change).
1435
1436                          * A valid sign that there's been a previous handshake
1437                          * in this connection is if s->s3->tmp.finish_md_len >
1438                          * 0.  (We are talking about a check that will happen
1439                          * in the Hello protocol round, well before a new
1440                          * Finished message could have been computed.) */
1441                         s->s3->next_proto_neg_seen = 1;
1442                         }
1443 #endif
1444
1445                 /* session ticket processed earlier */
1446 #ifndef OPENSSL_NO_SRTP
1447                 else if (SSL_IS_DTLS(s) && SSL_get_srtp_profiles(s)
1448                          && type == TLSEXT_TYPE_use_srtp)
1449                         {
1450                         if(ssl_parse_clienthello_use_srtp_ext(s, data, size,
1451                                                               al))
1452                                 return 0;
1453                         }
1454 #endif
1455
1456                 data+=size;
1457                 }
1458
1459         *p = data;
1460
1461         ri_check:
1462
1463         /* Need RI if renegotiating */
1464
1465         if (!renegotiate_seen && s->renegotiate &&
1466                 !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1467                 {
1468                 *al = SSL_AD_HANDSHAKE_FAILURE;
1469                 SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_TLSEXT,
1470                                 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
1471                 return 0;
1472                 }
1473
1474         return 1;
1475         }
1476
1477 #ifndef OPENSSL_NO_NEXTPROTONEG
1478 /* ssl_next_proto_validate validates a Next Protocol Negotiation block. No
1479  * elements of zero length are allowed and the set of elements must exactly fill
1480  * the length of the block. */
1481 static char ssl_next_proto_validate(unsigned char *d, unsigned len)
1482         {
1483         unsigned int off = 0;
1484
1485         while (off < len)
1486                 {
1487                 if (d[off] == 0)
1488                         return 0;
1489                 off += d[off];
1490                 off++;
1491                 }
1492
1493         return off == len;
1494         }
1495 #endif
1496
1497 int ssl_parse_serverhello_tlsext(SSL *s, unsigned char **p, unsigned char *d, int n, int *al)
1498         {
1499         unsigned short length;
1500         unsigned short type;
1501         unsigned short size;
1502         unsigned char *data = *p;
1503         int tlsext_servername = 0;
1504         int renegotiate_seen = 0;
1505
1506 #ifndef OPENSSL_NO_NEXTPROTONEG
1507         s->s3->next_proto_neg_seen = 0;
1508 #endif
1509
1510 #ifndef OPENSSL_NO_HEARTBEATS
1511         s->tlsext_heartbeat &= ~(SSL_TLSEXT_HB_ENABLED |
1512                                SSL_TLSEXT_HB_DONT_SEND_REQUESTS);
1513 #endif
1514
1515         if (data >= (d+n-2))
1516                 goto ri_check;
1517
1518         n2s(data,length);
1519         if (data+length != d+n)
1520                 {
1521                 *al = SSL_AD_DECODE_ERROR;
1522                 return 0;
1523                 }
1524
1525         while(data <= (d+n-4))
1526                 {
1527                 n2s(data,type);
1528                 n2s(data,size);
1529
1530                 if (data+size > (d+n))
1531                         goto ri_check;
1532
1533                 if (s->tlsext_debug_cb)
1534                         s->tlsext_debug_cb(s, 1, type, data, size,
1535                                                 s->tlsext_debug_arg);
1536
1537                 if (type == TLSEXT_TYPE_server_name)
1538                         {
1539                         if (s->tlsext_hostname == NULL || size > 0)
1540                                 {
1541                                 *al = TLS1_AD_UNRECOGNIZED_NAME;
1542                                 return 0;
1543                                 }
1544                         tlsext_servername = 1;
1545                         }
1546
1547 #ifndef OPENSSL_NO_EC
1548                 else if (type == TLSEXT_TYPE_ec_point_formats)
1549                         {
1550                         unsigned char *sdata = data;
1551                         int ecpointformatlist_length = *(sdata++);
1552
1553                         if (ecpointformatlist_length != size - 1 ||
1554                                 ecpointformatlist_length < 1)
1555                                 {
1556                                 *al = TLS1_AD_DECODE_ERROR;
1557                                 return 0;
1558                                 }
1559                         if (!s->hit)
1560                                 {
1561                                 s->session->tlsext_ecpointformatlist_length = 0;
1562                                 if (s->session->tlsext_ecpointformatlist != NULL) OPENSSL_free(s->session->tlsext_ecpointformatlist);
1563                                 if ((s->session->tlsext_ecpointformatlist = OPENSSL_malloc(ecpointformatlist_length)) == NULL)
1564                                         {
1565                                         *al = TLS1_AD_INTERNAL_ERROR;
1566                                         return 0;
1567                                         }
1568                                 s->session->tlsext_ecpointformatlist_length = ecpointformatlist_length;
1569                                 memcpy(s->session->tlsext_ecpointformatlist, sdata, ecpointformatlist_length);
1570                                 }
1571 #if 0
1572                         fprintf(stderr,"ssl_parse_serverhello_tlsext s->session->tlsext_ecpointformatlist ");
1573                         sdata = s->session->tlsext_ecpointformatlist;
1574                         for (i = 0; i < s->session->tlsext_ecpointformatlist_length; i++)
1575                                 fprintf(stderr,"%i ",*(sdata++));
1576                         fprintf(stderr,"\n");
1577 #endif
1578                         }
1579 #endif /* OPENSSL_NO_EC */
1580
1581                 else if (type == TLSEXT_TYPE_session_ticket)
1582                         {
1583                         if (s->tls_session_ticket_ext_cb &&
1584                             !s->tls_session_ticket_ext_cb(s, data, size, s->tls_session_ticket_ext_cb_arg))
1585                                 {
1586                                 *al = TLS1_AD_INTERNAL_ERROR;
1587                                 return 0;
1588                                 }
1589                         if ((SSL_get_options(s) & SSL_OP_NO_TICKET)
1590                                 || (size > 0))
1591                                 {
1592                                 *al = TLS1_AD_UNSUPPORTED_EXTENSION;
1593                                 return 0;
1594                                 }
1595                         s->tlsext_ticket_expected = 1;
1596                         }
1597 #ifdef TLSEXT_TYPE_opaque_prf_input
1598                 else if (type == TLSEXT_TYPE_opaque_prf_input &&
1599                      s->version != DTLS1_VERSION)
1600                         {
1601                         unsigned char *sdata = data;
1602
1603                         if (size < 2)
1604                                 {
1605                                 *al = SSL_AD_DECODE_ERROR;
1606                                 return 0;
1607                                 }
1608                         n2s(sdata, s->s3->server_opaque_prf_input_len);
1609                         if (s->s3->server_opaque_prf_input_len != size - 2)
1610                                 {
1611                                 *al = SSL_AD_DECODE_ERROR;
1612                                 return 0;
1613                                 }
1614
1615                         if (s->s3->server_opaque_prf_input != NULL) /* shouldn't really happen */
1616                                 OPENSSL_free(s->s3->server_opaque_prf_input);
1617                         if (s->s3->server_opaque_prf_input_len == 0)
1618                                 s->s3->server_opaque_prf_input = OPENSSL_malloc(1); /* dummy byte just to get non-NULL */
1619                         else
1620                                 s->s3->server_opaque_prf_input = BUF_memdup(sdata, s->s3->server_opaque_prf_input_len);
1621
1622                         if (s->s3->server_opaque_prf_input == NULL)
1623                                 {
1624                                 *al = TLS1_AD_INTERNAL_ERROR;
1625                                 return 0;
1626                                 }
1627                         }
1628 #endif
1629                 else if (type == TLSEXT_TYPE_status_request &&
1630                          s->version != DTLS1_VERSION)
1631                         {
1632                         /* MUST be empty and only sent if we've requested
1633                          * a status request message.
1634                          */
1635                         if ((s->tlsext_status_type == -1) || (size > 0))
1636                                 {
1637                                 *al = TLS1_AD_UNSUPPORTED_EXTENSION;
1638                                 return 0;
1639                                 }
1640                         /* Set flag to expect CertificateStatus message */
1641                         s->tlsext_status_expected = 1;
1642                         }
1643 #ifndef OPENSSL_NO_NEXTPROTONEG
1644                 else if (type == TLSEXT_TYPE_next_proto_neg &&
1645                          s->s3->tmp.finish_md_len == 0)
1646                         {
1647                         unsigned char *selected;
1648                         unsigned char selected_len;
1649
1650                         /* We must have requested it. */
1651                         if (s->ctx->next_proto_select_cb == NULL)
1652                                 {
1653                                 *al = TLS1_AD_UNSUPPORTED_EXTENSION;
1654                                 return 0;
1655                                 }
1656                         /* The data must be valid */
1657                         if (!ssl_next_proto_validate(data, size))
1658                                 {
1659                                 *al = TLS1_AD_DECODE_ERROR;
1660                                 return 0;
1661                                 }
1662                         if (s->ctx->next_proto_select_cb(s, &selected, &selected_len, data, size, s->ctx->next_proto_select_cb_arg) != SSL_TLSEXT_ERR_OK)
1663                                 {
1664                                 *al = TLS1_AD_INTERNAL_ERROR;
1665                                 return 0;
1666                                 }
1667                         s->next_proto_negotiated = OPENSSL_malloc(selected_len);
1668                         if (!s->next_proto_negotiated)
1669                                 {
1670                                 *al = TLS1_AD_INTERNAL_ERROR;
1671                                 return 0;
1672                                 }
1673                         memcpy(s->next_proto_negotiated, selected, selected_len);
1674                         s->next_proto_negotiated_len = selected_len;
1675                         s->s3->next_proto_neg_seen = 1;
1676                         }
1677 #endif
1678                 else if (type == TLSEXT_TYPE_renegotiate)
1679                         {
1680                         if(!ssl_parse_serverhello_renegotiate_ext(s, data, size, al))
1681                                 return 0;
1682                         renegotiate_seen = 1;
1683                         }
1684 #ifndef OPENSSL_NO_HEARTBEATS
1685                 else if (type == TLSEXT_TYPE_heartbeat)
1686                         {
1687                         switch(data[0])
1688                                 {
1689                                 case 0x01:      /* Server allows us to send HB requests */
1690                                                         s->tlsext_heartbeat |= SSL_TLSEXT_HB_ENABLED;
1691                                                         break;
1692                                 case 0x02:      /* Server doesn't accept HB requests */
1693                                                         s->tlsext_heartbeat |= SSL_TLSEXT_HB_ENABLED;
1694                                                         s->tlsext_heartbeat |= SSL_TLSEXT_HB_DONT_SEND_REQUESTS;
1695                                                         break;
1696                                 default:        *al = SSL_AD_ILLEGAL_PARAMETER;
1697                                                         return 0;
1698                                 }
1699                         }
1700 #endif
1701 #ifndef OPENSSL_NO_SRTP
1702                 else if (SSL_IS_DTLS(s) && type == TLSEXT_TYPE_use_srtp)
1703                         {
1704                         if(ssl_parse_serverhello_use_srtp_ext(s, data, size,
1705                                                               al))
1706                                 return 0;
1707                         }
1708 #endif
1709
1710                 data+=size;
1711                 }
1712
1713         if (data != d+n)
1714                 {
1715                 *al = SSL_AD_DECODE_ERROR;
1716                 return 0;
1717                 }
1718
1719         if (!s->hit && tlsext_servername == 1)
1720                 {
1721                 if (s->tlsext_hostname)
1722                         {
1723                         if (s->session->tlsext_hostname == NULL)
1724                                 {
1725                                 s->session->tlsext_hostname = BUF_strdup(s->tlsext_hostname);
1726                                 if (!s->session->tlsext_hostname)
1727                                         {
1728                                         *al = SSL_AD_UNRECOGNIZED_NAME;
1729                                         return 0;
1730                                         }
1731                                 }
1732                         else
1733                                 {
1734                                 *al = SSL_AD_DECODE_ERROR;
1735                                 return 0;
1736                                 }
1737                         }
1738                 }
1739
1740         *p = data;
1741
1742         ri_check:
1743
1744         /* Determine if we need to see RI. Strictly speaking if we want to
1745          * avoid an attack we should *always* see RI even on initial server
1746          * hello because the client doesn't see any renegotiation during an
1747          * attack. However this would mean we could not connect to any server
1748          * which doesn't support RI so for the immediate future tolerate RI
1749          * absence on initial connect only.
1750          */
1751         if (!renegotiate_seen
1752                 && !(s->options & SSL_OP_LEGACY_SERVER_CONNECT)
1753                 && !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1754                 {
1755                 *al = SSL_AD_HANDSHAKE_FAILURE;
1756                 SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_TLSEXT,
1757                                 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
1758                 return 0;
1759                 }
1760
1761         return 1;
1762         }
1763
1764
1765 int ssl_prepare_clienthello_tlsext(SSL *s)
1766         {
1767 #ifndef OPENSSL_NO_EC
1768         /* If we are client and using an elliptic curve cryptography cipher suite, send the point formats
1769          * and elliptic curves we support.
1770          */
1771         int using_ecc = 0;
1772         int i;
1773         unsigned char *j;
1774         unsigned long alg_k, alg_a;
1775         STACK_OF(SSL_CIPHER) *cipher_stack = SSL_get_ciphers(s);
1776
1777         for (i = 0; i < sk_SSL_CIPHER_num(cipher_stack); i++)
1778                 {
1779                 SSL_CIPHER *c = sk_SSL_CIPHER_value(cipher_stack, i);
1780
1781                 alg_k = c->algorithm_mkey;
1782                 alg_a = c->algorithm_auth;
1783                 if ((alg_k & (SSL_kEECDH|SSL_kECDHr|SSL_kECDHe) || (alg_a & SSL_aECDSA)))
1784                         {
1785                         using_ecc = 1;
1786                         break;
1787                         }
1788                 }
1789         using_ecc = using_ecc && (s->version >= TLS1_VERSION);
1790         if (using_ecc)
1791                 {
1792                 if (s->tlsext_ecpointformatlist != NULL) OPENSSL_free(s->tlsext_ecpointformatlist);
1793                 if ((s->tlsext_ecpointformatlist = OPENSSL_malloc(3)) == NULL)
1794                         {
1795                         SSLerr(SSL_F_SSL_PREPARE_CLIENTHELLO_TLSEXT,ERR_R_MALLOC_FAILURE);
1796                         return -1;
1797                         }
1798                 s->tlsext_ecpointformatlist_length = 3;
1799                 s->tlsext_ecpointformatlist[0] = TLSEXT_ECPOINTFORMAT_uncompressed;
1800                 s->tlsext_ecpointformatlist[1] = TLSEXT_ECPOINTFORMAT_ansiX962_compressed_prime;
1801                 s->tlsext_ecpointformatlist[2] = TLSEXT_ECPOINTFORMAT_ansiX962_compressed_char2;
1802
1803                 /* we support all named elliptic curves in draft-ietf-tls-ecc-12 */
1804                 if (s->tlsext_ellipticcurvelist != NULL) OPENSSL_free(s->tlsext_ellipticcurvelist);
1805                 s->tlsext_ellipticcurvelist_length = sizeof(pref_list)/sizeof(pref_list[0]) * 2;
1806                 if ((s->tlsext_ellipticcurvelist = OPENSSL_malloc(s->tlsext_ellipticcurvelist_length)) == NULL)
1807                         {
1808                         s->tlsext_ellipticcurvelist_length = 0;
1809                         SSLerr(SSL_F_SSL_PREPARE_CLIENTHELLO_TLSEXT,ERR_R_MALLOC_FAILURE);
1810                         return -1;
1811                         }
1812                 for (i = 0, j = s->tlsext_ellipticcurvelist; (unsigned int)i <
1813                                 sizeof(pref_list)/sizeof(pref_list[0]); i++)
1814                         {
1815                         int id = tls1_ec_nid2curve_id(pref_list[i]);
1816                         s2n(id,j);
1817                         }
1818                 }
1819 #endif /* OPENSSL_NO_EC */
1820
1821 #ifdef TLSEXT_TYPE_opaque_prf_input
1822         {
1823                 int r = 1;
1824
1825                 if (s->ctx->tlsext_opaque_prf_input_callback != 0)
1826                         {
1827                         r = s->ctx->tlsext_opaque_prf_input_callback(s, NULL, 0, s->ctx->tlsext_opaque_prf_input_callback_arg);
1828                         if (!r)
1829                                 return -1;
1830                         }
1831
1832                 if (s->tlsext_opaque_prf_input != NULL)
1833                         {
1834                         if (s->s3->client_opaque_prf_input != NULL) /* shouldn't really happen */
1835                                 OPENSSL_free(s->s3->client_opaque_prf_input);
1836
1837                         if (s->tlsext_opaque_prf_input_len == 0)
1838                                 s->s3->client_opaque_prf_input = OPENSSL_malloc(1); /* dummy byte just to get non-NULL */
1839                         else
1840                                 s->s3->client_opaque_prf_input = BUF_memdup(s->tlsext_opaque_prf_input, s->tlsext_opaque_prf_input_len);
1841                         if (s->s3->client_opaque_prf_input == NULL)
1842                                 {
1843                                 SSLerr(SSL_F_SSL_PREPARE_CLIENTHELLO_TLSEXT,ERR_R_MALLOC_FAILURE);
1844                                 return -1;
1845                                 }
1846                         s->s3->client_opaque_prf_input_len = s->tlsext_opaque_prf_input_len;
1847                         }
1848
1849                 if (r == 2)
1850                         /* at callback's request, insist on receiving an appropriate server opaque PRF input */
1851                         s->s3->server_opaque_prf_input_len = s->tlsext_opaque_prf_input_len;
1852         }
1853 #endif
1854
1855         return 1;
1856         }
1857
1858 int ssl_prepare_serverhello_tlsext(SSL *s)
1859         {
1860 #ifndef OPENSSL_NO_EC
1861         /* If we are server and using an ECC cipher suite, send the point formats we support
1862          * if the client sent us an ECPointsFormat extension.  Note that the server is not
1863          * supposed to send an EllipticCurves extension.
1864          */
1865
1866         unsigned long alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
1867         unsigned long alg_a = s->s3->tmp.new_cipher->algorithm_auth;
1868         int using_ecc = (alg_k & (SSL_kEECDH|SSL_kECDHr|SSL_kECDHe)) || (alg_a & SSL_aECDSA);
1869         using_ecc = using_ecc && (s->session->tlsext_ecpointformatlist != NULL);
1870
1871         if (using_ecc)
1872                 {
1873                 if (s->tlsext_ecpointformatlist != NULL) OPENSSL_free(s->tlsext_ecpointformatlist);
1874                 if ((s->tlsext_ecpointformatlist = OPENSSL_malloc(3)) == NULL)
1875                         {
1876                         SSLerr(SSL_F_SSL_PREPARE_SERVERHELLO_TLSEXT,ERR_R_MALLOC_FAILURE);
1877                         return -1;
1878                         }
1879                 s->tlsext_ecpointformatlist_length = 3;
1880                 s->tlsext_ecpointformatlist[0] = TLSEXT_ECPOINTFORMAT_uncompressed;
1881                 s->tlsext_ecpointformatlist[1] = TLSEXT_ECPOINTFORMAT_ansiX962_compressed_prime;
1882                 s->tlsext_ecpointformatlist[2] = TLSEXT_ECPOINTFORMAT_ansiX962_compressed_char2;
1883                 }
1884 #endif /* OPENSSL_NO_EC */
1885
1886         return 1;
1887         }
1888
1889 int ssl_check_clienthello_tlsext_early(SSL *s)
1890         {
1891         int ret=SSL_TLSEXT_ERR_NOACK;
1892         int al = SSL_AD_UNRECOGNIZED_NAME;
1893
1894 #ifndef OPENSSL_NO_EC
1895         /* The handling of the ECPointFormats extension is done elsewhere, namely in
1896          * ssl3_choose_cipher in s3_lib.c.
1897          */
1898         /* The handling of the EllipticCurves extension is done elsewhere, namely in
1899          * ssl3_choose_cipher in s3_lib.c.
1900          */
1901 #endif
1902
1903         if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0)
1904                 ret = s->ctx->tlsext_servername_callback(s, &al, s->ctx->tlsext_servername_arg);
1905         else if (s->initial_ctx != NULL && s->initial_ctx->tlsext_servername_callback != 0)
1906                 ret = s->initial_ctx->tlsext_servername_callback(s, &al, s->initial_ctx->tlsext_servername_arg);
1907
1908 #ifdef TLSEXT_TYPE_opaque_prf_input
1909         {
1910                 /* This sort of belongs into ssl_prepare_serverhello_tlsext(),
1911                  * but we might be sending an alert in response to the client hello,
1912                  * so this has to happen here in
1913                  * ssl_check_clienthello_tlsext_early(). */
1914
1915                 int r = 1;
1916
1917                 if (s->ctx->tlsext_opaque_prf_input_callback != 0)
1918                         {
1919                         r = s->ctx->tlsext_opaque_prf_input_callback(s, NULL, 0, s->ctx->tlsext_opaque_prf_input_callback_arg);
1920                         if (!r)
1921                                 {
1922                                 ret = SSL_TLSEXT_ERR_ALERT_FATAL;
1923                                 al = SSL_AD_INTERNAL_ERROR;
1924                                 goto err;
1925                                 }
1926                         }
1927
1928                 if (s->s3->server_opaque_prf_input != NULL) /* shouldn't really happen */
1929                         OPENSSL_free(s->s3->server_opaque_prf_input);
1930                 s->s3->server_opaque_prf_input = NULL;
1931
1932                 if (s->tlsext_opaque_prf_input != NULL)
1933                         {
1934                         if (s->s3->client_opaque_prf_input != NULL &&
1935                                 s->s3->client_opaque_prf_input_len == s->tlsext_opaque_prf_input_len)
1936                                 {
1937                                 /* can only use this extension if we have a server opaque PRF input
1938                                  * of the same length as the client opaque PRF input! */
1939
1940                                 if (s->tlsext_opaque_prf_input_len == 0)
1941                                         s->s3->server_opaque_prf_input = OPENSSL_malloc(1); /* dummy byte just to get non-NULL */
1942                                 else
1943                                         s->s3->server_opaque_prf_input = BUF_memdup(s->tlsext_opaque_prf_input, s->tlsext_opaque_prf_input_len);
1944                                 if (s->s3->server_opaque_prf_input == NULL)
1945                                         {
1946                                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
1947                                         al = SSL_AD_INTERNAL_ERROR;
1948                                         goto err;
1949                                         }
1950                                 s->s3->server_opaque_prf_input_len = s->tlsext_opaque_prf_input_len;
1951                                 }
1952                         }
1953
1954                 if (r == 2 && s->s3->server_opaque_prf_input == NULL)
1955                         {
1956                         /* The callback wants to enforce use of the extension,
1957                          * but we can't do that with the client opaque PRF input;
1958                          * abort the handshake.
1959                          */
1960                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
1961                         al = SSL_AD_HANDSHAKE_FAILURE;
1962                         }
1963         }
1964
1965  err:
1966 #endif
1967         switch (ret)
1968                 {
1969                 case SSL_TLSEXT_ERR_ALERT_FATAL:
1970                         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1971                         return -1;
1972
1973                 case SSL_TLSEXT_ERR_ALERT_WARNING:
1974                         ssl3_send_alert(s,SSL3_AL_WARNING,al);
1975                         return 1;
1976
1977                 case SSL_TLSEXT_ERR_NOACK:
1978                         s->servername_done=0;
1979                         default:
1980                 return 1;
1981                 }
1982         }
1983
1984 int ssl_check_clienthello_tlsext_late(SSL *s)
1985         {
1986         int ret = SSL_TLSEXT_ERR_OK;
1987         int al;
1988
1989         /* If status request then ask callback what to do.
1990          * Note: this must be called after servername callbacks in case
1991          * the certificate has changed, and must be called after the cipher
1992          * has been chosen because this may influence which certificate is sent
1993          */
1994         if ((s->tlsext_status_type != -1) && s->ctx && s->ctx->tlsext_status_cb)
1995                 {
1996                 int r;
1997                 CERT_PKEY *certpkey;
1998                 certpkey = ssl_get_server_send_pkey(s);
1999                 /* If no certificate can't return certificate status */
2000                 if (certpkey == NULL)
2001                         {
2002                         s->tlsext_status_expected = 0;
2003                         return 1;
2004                         }
2005                 /* Set current certificate to one we will use so
2006                  * SSL_get_certificate et al can pick it up.
2007                  */
2008                 s->cert->key = certpkey;
2009                 r = s->ctx->tlsext_status_cb(s, s->ctx->tlsext_status_arg);
2010                 switch (r)
2011                         {
2012                         /* We don't want to send a status request response */
2013                         case SSL_TLSEXT_ERR_NOACK:
2014                                 s->tlsext_status_expected = 0;
2015                                 break;
2016                         /* status request response should be sent */
2017                         case SSL_TLSEXT_ERR_OK:
2018                                 if (s->tlsext_ocsp_resp)
2019                                         s->tlsext_status_expected = 1;
2020                                 else
2021                                         s->tlsext_status_expected = 0;
2022                                 break;
2023                         /* something bad happened */
2024                         case SSL_TLSEXT_ERR_ALERT_FATAL:
2025                                 ret = SSL_TLSEXT_ERR_ALERT_FATAL;
2026                                 al = SSL_AD_INTERNAL_ERROR;
2027                                 goto err;
2028                         }
2029                 }
2030         else
2031                 s->tlsext_status_expected = 0;
2032
2033  err:
2034         switch (ret)
2035                 {
2036                 case SSL_TLSEXT_ERR_ALERT_FATAL:
2037                         ssl3_send_alert(s,SSL3_AL_FATAL,al);
2038                         return -1;
2039
2040                 case SSL_TLSEXT_ERR_ALERT_WARNING:
2041                         ssl3_send_alert(s,SSL3_AL_WARNING,al);
2042                         return 1;
2043
2044                 default:
2045                         return 1;
2046                 }
2047         }
2048
2049 int ssl_check_serverhello_tlsext(SSL *s)
2050         {
2051         int ret=SSL_TLSEXT_ERR_NOACK;
2052         int al = SSL_AD_UNRECOGNIZED_NAME;
2053
2054 #ifndef OPENSSL_NO_EC
2055         /* If we are client and using an elliptic curve cryptography cipher
2056          * suite, then if server returns an EC point formats lists extension
2057          * it must contain uncompressed.
2058          */
2059         unsigned long alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
2060         unsigned long alg_a = s->s3->tmp.new_cipher->algorithm_auth;
2061         if ((s->tlsext_ecpointformatlist != NULL) && (s->tlsext_ecpointformatlist_length > 0) &&
2062             (s->session->tlsext_ecpointformatlist != NULL) && (s->session->tlsext_ecpointformatlist_length > 0) &&
2063             ((alg_k & (SSL_kEECDH|SSL_kECDHr|SSL_kECDHe)) || (alg_a & SSL_aECDSA)))
2064                 {
2065                 /* we are using an ECC cipher */
2066                 size_t i;
2067                 unsigned char *list;
2068                 int found_uncompressed = 0;
2069                 list = s->session->tlsext_ecpointformatlist;
2070                 for (i = 0; i < s->session->tlsext_ecpointformatlist_length; i++)
2071                         {
2072                         if (*(list++) == TLSEXT_ECPOINTFORMAT_uncompressed)
2073                                 {
2074                                 found_uncompressed = 1;
2075                                 break;
2076                                 }
2077                         }
2078                 if (!found_uncompressed)
2079                         {
2080                         SSLerr(SSL_F_SSL_CHECK_SERVERHELLO_TLSEXT,SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST);
2081                         return -1;
2082                         }
2083                 }
2084         ret = SSL_TLSEXT_ERR_OK;
2085 #endif /* OPENSSL_NO_EC */
2086
2087         if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0)
2088                 ret = s->ctx->tlsext_servername_callback(s, &al, s->ctx->tlsext_servername_arg);
2089         else if (s->initial_ctx != NULL && s->initial_ctx->tlsext_servername_callback != 0)
2090                 ret = s->initial_ctx->tlsext_servername_callback(s, &al, s->initial_ctx->tlsext_servername_arg);
2091
2092 #ifdef TLSEXT_TYPE_opaque_prf_input
2093         if (s->s3->server_opaque_prf_input_len > 0)
2094                 {
2095                 /* This case may indicate that we, as a client, want to insist on using opaque PRF inputs.
2096                  * So first verify that we really have a value from the server too. */
2097
2098                 if (s->s3->server_opaque_prf_input == NULL)
2099                         {
2100                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
2101                         al = SSL_AD_HANDSHAKE_FAILURE;
2102                         }
2103
2104                 /* Anytime the server *has* sent an opaque PRF input, we need to check
2105                  * that we have a client opaque PRF input of the same size. */
2106                 if (s->s3->client_opaque_prf_input == NULL ||
2107                     s->s3->client_opaque_prf_input_len != s->s3->server_opaque_prf_input_len)
2108                         {
2109                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
2110                         al = SSL_AD_ILLEGAL_PARAMETER;
2111                         }
2112                 }
2113 #endif
2114
2115         /* If we've requested certificate status and we wont get one
2116          * tell the callback
2117          */
2118         if ((s->tlsext_status_type != -1) && !(s->tlsext_status_expected)
2119                         && s->ctx && s->ctx->tlsext_status_cb)
2120                 {
2121                 int r;
2122                 /* Set resp to NULL, resplen to -1 so callback knows
2123                  * there is no response.
2124                  */
2125                 if (s->tlsext_ocsp_resp)
2126                         {
2127                         OPENSSL_free(s->tlsext_ocsp_resp);
2128                         s->tlsext_ocsp_resp = NULL;
2129                         }
2130                 s->tlsext_ocsp_resplen = -1;
2131                 r = s->ctx->tlsext_status_cb(s, s->ctx->tlsext_status_arg);
2132                 if (r == 0)
2133                         {
2134                         al = SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE;
2135                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
2136                         }
2137                 if (r < 0)
2138                         {
2139                         al = SSL_AD_INTERNAL_ERROR;
2140                         ret = SSL_TLSEXT_ERR_ALERT_FATAL;
2141                         }
2142                 }
2143
2144         switch (ret)
2145                 {
2146                 case SSL_TLSEXT_ERR_ALERT_FATAL:
2147                         ssl3_send_alert(s,SSL3_AL_FATAL,al);
2148                         return -1;
2149
2150                 case SSL_TLSEXT_ERR_ALERT_WARNING:
2151                         ssl3_send_alert(s,SSL3_AL_WARNING,al);
2152                         return 1;
2153
2154                 case SSL_TLSEXT_ERR_NOACK:
2155                         s->servername_done=0;
2156                         default:
2157                 return 1;
2158                 }
2159         }
2160
2161 /* Since the server cache lookup is done early on in the processing of the
2162  * ClientHello, and other operations depend on the result, we need to handle
2163  * any TLS session ticket extension at the same time.
2164  *
2165  *   session_id: points at the session ID in the ClientHello. This code will
2166  *       read past the end of this in order to parse out the session ticket
2167  *       extension, if any.
2168  *   len: the length of the session ID.
2169  *   limit: a pointer to the first byte after the ClientHello.
2170  *   ret: (output) on return, if a ticket was decrypted, then this is set to
2171  *       point to the resulting session.
2172  *
2173  * If s->tls_session_secret_cb is set then we are expecting a pre-shared key
2174  * ciphersuite, in which case we have no use for session tickets and one will
2175  * never be decrypted, nor will s->tlsext_ticket_expected be set to 1.
2176  *
2177  * Returns:
2178  *   -1: fatal error, either from parsing or decrypting the ticket.
2179  *    0: no ticket was found (or was ignored, based on settings).
2180  *    1: a zero length extension was found, indicating that the client supports
2181  *       session tickets but doesn't currently have one to offer.
2182  *    2: either s->tls_session_secret_cb was set, or a ticket was offered but
2183  *       couldn't be decrypted because of a non-fatal error.
2184  *    3: a ticket was successfully decrypted and *ret was set.
2185  *
2186  * Side effects:
2187  *   Sets s->tlsext_ticket_expected to 1 if the server will have to issue
2188  *   a new session ticket to the client because the client indicated support
2189  *   (and s->tls_session_secret_cb is NULL) but the client either doesn't have
2190  *   a session ticket or we couldn't use the one it gave us, or if
2191  *   s->ctx->tlsext_ticket_key_cb asked to renew the client's ticket.
2192  *   Otherwise, s->tlsext_ticket_expected is set to 0.
2193  */
2194 int tls1_process_ticket(SSL *s, unsigned char *session_id, int len,
2195                         const unsigned char *limit, SSL_SESSION **ret)
2196         {
2197         /* Point after session ID in client hello */
2198         const unsigned char *p = session_id + len;
2199         unsigned short i;
2200
2201         *ret = NULL;
2202         s->tlsext_ticket_expected = 0;
2203
2204         /* If tickets disabled behave as if no ticket present
2205          * to permit stateful resumption.
2206          */
2207         if (SSL_get_options(s) & SSL_OP_NO_TICKET)
2208                 return 0;
2209         if ((s->version <= SSL3_VERSION) || !limit)
2210                 return 0;
2211         if (p >= limit)
2212                 return -1;
2213         /* Skip past DTLS cookie */
2214         if (s->version == DTLS1_VERSION || s->version == DTLS1_BAD_VER)
2215                 {
2216                 i = *(p++);
2217                 p+= i;
2218                 if (p >= limit)
2219                         return -1;
2220                 }
2221         /* Skip past cipher list */
2222         n2s(p, i);
2223         p+= i;
2224         if (p >= limit)
2225                 return -1;
2226         /* Skip past compression algorithm list */
2227         i = *(p++);
2228         p += i;
2229         if (p > limit)
2230                 return -1;
2231         /* Now at start of extensions */
2232         if ((p + 2) >= limit)
2233                 return 0;
2234         n2s(p, i);
2235         while ((p + 4) <= limit)
2236                 {
2237                 unsigned short type, size;
2238                 n2s(p, type);
2239                 n2s(p, size);
2240                 if (p + size > limit)
2241                         return 0;
2242                 if (type == TLSEXT_TYPE_session_ticket)
2243                         {
2244                         int r;
2245                         if (size == 0)
2246                                 {
2247                                 /* The client will accept a ticket but doesn't
2248                                  * currently have one. */
2249                                 s->tlsext_ticket_expected = 1;
2250                                 return 1;
2251                                 }
2252                         if (s->tls_session_secret_cb)
2253                                 {
2254                                 /* Indicate that the ticket couldn't be
2255                                  * decrypted rather than generating the session
2256                                  * from ticket now, trigger abbreviated
2257                                  * handshake based on external mechanism to
2258                                  * calculate the master secret later. */
2259                                 return 2;
2260                                 }
2261                         r = tls_decrypt_ticket(s, p, size, session_id, len, ret);
2262                         switch (r)
2263                                 {
2264                                 case 2: /* ticket couldn't be decrypted */
2265                                         s->tlsext_ticket_expected = 1;
2266                                         return 2;
2267                                 case 3: /* ticket was decrypted */
2268                                         return r;
2269                                 case 4: /* ticket decrypted but need to renew */
2270                                         s->tlsext_ticket_expected = 1;
2271                                         return 3;
2272                                 default: /* fatal error */
2273                                         return -1;
2274                                 }
2275                         }
2276                 p += size;
2277                 }
2278         return 0;
2279         }
2280
2281 /* tls_decrypt_ticket attempts to decrypt a session ticket.
2282  *
2283  *   etick: points to the body of the session ticket extension.
2284  *   eticklen: the length of the session tickets extenion.
2285  *   sess_id: points at the session ID.
2286  *   sesslen: the length of the session ID.
2287  *   psess: (output) on return, if a ticket was decrypted, then this is set to
2288  *       point to the resulting session.
2289  *
2290  * Returns:
2291  *   -1: fatal error, either from parsing or decrypting the ticket.
2292  *    2: the ticket couldn't be decrypted.
2293  *    3: a ticket was successfully decrypted and *psess was set.
2294  *    4: same as 3, but the ticket needs to be renewed.
2295  */
2296 static int tls_decrypt_ticket(SSL *s, const unsigned char *etick, int eticklen,
2297                                 const unsigned char *sess_id, int sesslen,
2298                                 SSL_SESSION **psess)
2299         {
2300         SSL_SESSION *sess;
2301         unsigned char *sdec;
2302         const unsigned char *p;
2303         int slen, mlen, renew_ticket = 0;
2304         unsigned char tick_hmac[EVP_MAX_MD_SIZE];
2305         HMAC_CTX hctx;
2306         EVP_CIPHER_CTX ctx;
2307         SSL_CTX *tctx = s->initial_ctx;
2308         /* Need at least keyname + iv + some encrypted data */
2309         if (eticklen < 48)
2310                 return 2;
2311         /* Initialize session ticket encryption and HMAC contexts */
2312         HMAC_CTX_init(&hctx);
2313         EVP_CIPHER_CTX_init(&ctx);
2314         if (tctx->tlsext_ticket_key_cb)
2315                 {
2316                 unsigned char *nctick = (unsigned char *)etick;
2317                 int rv = tctx->tlsext_ticket_key_cb(s, nctick, nctick + 16,
2318                                                         &ctx, &hctx, 0);
2319                 if (rv < 0)
2320                         return -1;
2321                 if (rv == 0)
2322                         return 2;
2323                 if (rv == 2)
2324                         renew_ticket = 1;
2325                 }
2326         else
2327                 {
2328                 /* Check key name matches */
2329                 if (memcmp(etick, tctx->tlsext_tick_key_name, 16))
2330                         return 2;
2331                 HMAC_Init_ex(&hctx, tctx->tlsext_tick_hmac_key, 16,
2332                                         tlsext_tick_md(), NULL);
2333                 EVP_DecryptInit_ex(&ctx, EVP_aes_128_cbc(), NULL,
2334                                 tctx->tlsext_tick_aes_key, etick + 16);
2335                 }
2336         /* Attempt to process session ticket, first conduct sanity and
2337          * integrity checks on ticket.
2338          */
2339         mlen = HMAC_size(&hctx);
2340         if (mlen < 0)
2341                 {
2342                 EVP_CIPHER_CTX_cleanup(&ctx);
2343                 return -1;
2344                 }
2345         eticklen -= mlen;
2346         /* Check HMAC of encrypted ticket */
2347         HMAC_Update(&hctx, etick, eticklen);
2348         HMAC_Final(&hctx, tick_hmac, NULL);
2349         HMAC_CTX_cleanup(&hctx);
2350         if (CRYPTO_memcmp(tick_hmac, etick + eticklen, mlen))
2351                 {
2352                 EVP_CIPHER_CTX_cleanup(&ctx);
2353                 return 2;
2354                 }
2355         /* Attempt to decrypt session data */
2356         /* Move p after IV to start of encrypted ticket, update length */
2357         p = etick + 16 + EVP_CIPHER_CTX_iv_length(&ctx);
2358         eticklen -= 16 + EVP_CIPHER_CTX_iv_length(&ctx);
2359         sdec = OPENSSL_malloc(eticklen);
2360         if (!sdec)
2361                 {
2362                 EVP_CIPHER_CTX_cleanup(&ctx);
2363                 return -1;
2364                 }
2365         EVP_DecryptUpdate(&ctx, sdec, &slen, p, eticklen);
2366         if (EVP_DecryptFinal(&ctx, sdec + slen, &mlen) <= 0)
2367                 {
2368                 EVP_CIPHER_CTX_cleanup(&ctx);
2369                 OPENSSL_free(sdec);
2370                 return 2;
2371                 }
2372         slen += mlen;
2373         EVP_CIPHER_CTX_cleanup(&ctx);
2374         p = sdec;
2375
2376         sess = d2i_SSL_SESSION(NULL, &p, slen);
2377         OPENSSL_free(sdec);
2378         if (sess)
2379                 {
2380                 /* The session ID, if non-empty, is used by some clients to
2381                  * detect that the ticket has been accepted. So we copy it to
2382                  * the session structure. If it is empty set length to zero
2383                  * as required by standard.
2384                  */
2385                 if (sesslen)
2386                         memcpy(sess->session_id, sess_id, sesslen);
2387                 sess->session_id_length = sesslen;
2388                 *psess = sess;
2389                 if (renew_ticket)
2390                         return 4;
2391                 else
2392                         return 3;
2393                 }
2394         ERR_clear_error();
2395         /* For session parse failure, indicate that we need to send a new
2396          * ticket. */
2397         return 2;
2398         }
2399
2400 /* Tables to translate from NIDs to TLS v1.2 ids */
2401
2402 typedef struct
2403         {
2404         int nid;
2405         int id;
2406         } tls12_lookup;
2407
2408 static tls12_lookup tls12_md[] = {
2409 #ifndef OPENSSL_NO_MD5
2410         {NID_md5, TLSEXT_hash_md5},
2411 #endif
2412 #ifndef OPENSSL_NO_SHA
2413         {NID_sha1, TLSEXT_hash_sha1},
2414 #endif
2415 #ifndef OPENSSL_NO_SHA256
2416         {NID_sha224, TLSEXT_hash_sha224},
2417         {NID_sha256, TLSEXT_hash_sha256},
2418 #endif
2419 #ifndef OPENSSL_NO_SHA512
2420         {NID_sha384, TLSEXT_hash_sha384},
2421         {NID_sha512, TLSEXT_hash_sha512}
2422 #endif
2423 };
2424
2425 static tls12_lookup tls12_sig[] = {
2426 #ifndef OPENSSL_NO_RSA
2427         {EVP_PKEY_RSA, TLSEXT_signature_rsa},
2428 #endif
2429 #ifndef OPENSSL_NO_DSA
2430         {EVP_PKEY_DSA, TLSEXT_signature_dsa},
2431 #endif
2432 #ifndef OPENSSL_NO_ECDSA
2433         {EVP_PKEY_EC, TLSEXT_signature_ecdsa}
2434 #endif
2435 };
2436
2437 static int tls12_find_id(int nid, tls12_lookup *table, size_t tlen)
2438         {
2439         size_t i;
2440         for (i = 0; i < tlen; i++)
2441                 {
2442                 if (table[i].nid == nid)
2443                         return table[i].id;
2444                 }
2445         return -1;
2446         }
2447 #if 0
2448 static int tls12_find_nid(int id, tls12_lookup *table, size_t tlen)
2449         {
2450         size_t i;
2451         for (i = 0; i < tlen; i++)
2452                 {
2453                 if (table[i].id == id)
2454                         return table[i].nid;
2455                 }
2456         return -1;
2457         }
2458 #endif
2459
2460 int tls12_get_sigandhash(unsigned char *p, const EVP_PKEY *pk, const EVP_MD *md)
2461         {
2462         int sig_id, md_id;
2463         if (!md)
2464                 return 0;
2465         md_id = tls12_find_id(EVP_MD_type(md), tls12_md,
2466                                 sizeof(tls12_md)/sizeof(tls12_lookup));
2467         if (md_id == -1)
2468                 return 0;
2469         sig_id = tls12_get_sigid(pk);
2470         if (sig_id == -1)
2471                 return 0;
2472         p[0] = (unsigned char)md_id;
2473         p[1] = (unsigned char)sig_id;
2474         return 1;
2475         }
2476
2477 int tls12_get_sigid(const EVP_PKEY *pk)
2478         {
2479         return tls12_find_id(pk->type, tls12_sig,
2480                                 sizeof(tls12_sig)/sizeof(tls12_lookup));
2481         }
2482
2483 const EVP_MD *tls12_get_hash(unsigned char hash_alg)
2484         {
2485         switch(hash_alg)
2486                 {
2487 #ifndef OPENSSL_NO_SHA
2488                 case TLSEXT_hash_sha1:
2489                 return EVP_sha1();
2490 #endif
2491 #ifndef OPENSSL_NO_SHA256
2492                 case TLSEXT_hash_sha224:
2493                 return EVP_sha224();
2494
2495                 case TLSEXT_hash_sha256:
2496                 return EVP_sha256();
2497 #endif
2498 #ifndef OPENSSL_NO_SHA512
2499                 case TLSEXT_hash_sha384:
2500                 return EVP_sha384();
2501
2502                 case TLSEXT_hash_sha512:
2503                 return EVP_sha512();
2504 #endif
2505                 default:
2506                 return NULL;
2507
2508                 }
2509         }
2510
2511 /* Set preferred digest for each key type */
2512
2513 int tls1_process_sigalgs(SSL *s, const unsigned char *data, int dsize)
2514         {
2515         int i, idx;
2516         const EVP_MD *md;
2517         CERT *c = s->cert;
2518         /* Extension ignored for TLS versions below 1.2 */
2519         if (TLS1_get_version(s) < TLS1_2_VERSION)
2520                 return 1;
2521         /* Should never happen */
2522         if (!c)
2523                 return 0;
2524
2525         c->pkeys[SSL_PKEY_DSA_SIGN].digest = NULL;
2526         c->pkeys[SSL_PKEY_RSA_SIGN].digest = NULL;
2527         c->pkeys[SSL_PKEY_RSA_ENC].digest = NULL;
2528         c->pkeys[SSL_PKEY_ECC].digest = NULL;
2529
2530         for (i = 0; i < dsize; i += 2)
2531                 {
2532                 unsigned char hash_alg = data[i], sig_alg = data[i+1];
2533
2534                 switch(sig_alg)
2535                         {
2536 #ifndef OPENSSL_NO_RSA
2537                         case TLSEXT_signature_rsa:
2538                         idx = SSL_PKEY_RSA_SIGN;
2539                         break;
2540 #endif
2541 #ifndef OPENSSL_NO_DSA
2542                         case TLSEXT_signature_dsa:
2543                         idx = SSL_PKEY_DSA_SIGN;
2544                         break;
2545 #endif
2546 #ifndef OPENSSL_NO_ECDSA
2547                         case TLSEXT_signature_ecdsa:
2548                         idx = SSL_PKEY_ECC;
2549                         break;
2550 #endif
2551                         default:
2552                         continue;
2553                         }
2554
2555                 if (c->pkeys[idx].digest == NULL)
2556                         {
2557                         md = tls12_get_hash(hash_alg);
2558                         if (md)
2559                                 {
2560                                 c->pkeys[idx].digest = md;
2561                                 if (idx == SSL_PKEY_RSA_SIGN)
2562                                         c->pkeys[SSL_PKEY_RSA_ENC].digest = md;
2563                                 }
2564                         }
2565
2566                 }
2567
2568
2569         /* Set any remaining keys to default values. NOTE: if alg is not
2570          * supported it stays as NULL.
2571          */
2572 #ifndef OPENSSL_NO_DSA
2573         if (!c->pkeys[SSL_PKEY_DSA_SIGN].digest)
2574                 c->pkeys[SSL_PKEY_DSA_SIGN].digest = EVP_sha1();
2575 #endif
2576 #ifndef OPENSSL_NO_RSA
2577         if (!c->pkeys[SSL_PKEY_RSA_SIGN].digest)
2578                 {
2579                 c->pkeys[SSL_PKEY_RSA_SIGN].digest = EVP_sha1();
2580                 c->pkeys[SSL_PKEY_RSA_ENC].digest = EVP_sha1();
2581                 }
2582 #endif
2583 #ifndef OPENSSL_NO_ECDSA
2584         if (!c->pkeys[SSL_PKEY_ECC].digest)
2585                 c->pkeys[SSL_PKEY_ECC].digest = EVP_sha1();
2586 #endif
2587         return 1;
2588         }
2589
2590 #endif
2591
2592 #ifndef OPENSSL_NO_HEARTBEATS
2593 int
2594 tls1_process_heartbeat(SSL *s)
2595         {
2596         unsigned char *p = &s->s3->rrec.data[0], *pl;
2597         unsigned short hbtype;
2598         unsigned int payload;
2599         unsigned int padding = 16; /* Use minimum padding */
2600
2601         if (s->msg_callback)
2602                 s->msg_callback(0, s->version, TLS1_RT_HEARTBEAT,
2603                         &s->s3->rrec.data[0], s->s3->rrec.length,
2604                         s, s->msg_callback_arg);
2605
2606         /* Read type and payload length first */
2607         if (1 + 2 + 16 > s->s3->rrec.length)
2608                 return 0; /* silently discard */
2609         hbtype = *p++;
2610         n2s(p, payload);
2611         if (1 + 2 + payload + 16 > s->s3->rrec.length)
2612                 return 0; /* silently discard per RFC 6520 sec. 4 */
2613         pl = p;
2614
2615         if (hbtype == TLS1_HB_REQUEST)
2616                 {
2617                 unsigned char *buffer, *bp;
2618                 int r;
2619
2620                 /* Allocate memory for the response, size is 1 bytes
2621                  * message type, plus 2 bytes payload length, plus
2622                  * payload, plus padding
2623                  */
2624                 buffer = OPENSSL_malloc(1 + 2 + payload + padding);
2625                 bp = buffer;
2626
2627                 /* Enter response type, length and copy payload */
2628                 *bp++ = TLS1_HB_RESPONSE;
2629                 s2n(payload, bp);
2630                 memcpy(bp, pl, payload);
2631                 bp += payload;
2632                 /* Random padding */
2633                 RAND_pseudo_bytes(bp, padding);
2634
2635                 r = ssl3_write_bytes(s, TLS1_RT_HEARTBEAT, buffer, 3 + payload + padding);
2636
2637                 if (r >= 0 && s->msg_callback)
2638                         s->msg_callback(1, s->version, TLS1_RT_HEARTBEAT,
2639                                 buffer, 3 + payload + padding,
2640                                 s, s->msg_callback_arg);
2641
2642                 OPENSSL_free(buffer);
2643
2644                 if (r < 0)
2645                         return r;
2646                 }
2647         else if (hbtype == TLS1_HB_RESPONSE)
2648                 {
2649                 unsigned int seq;
2650
2651                 /* We only send sequence numbers (2 bytes unsigned int),
2652                  * and 16 random bytes, so we just try to read the
2653                  * sequence number */
2654                 n2s(pl, seq);
2655
2656                 if (payload == 18 && seq == s->tlsext_hb_seq)
2657                         {
2658                         s->tlsext_hb_seq++;
2659                         s->tlsext_hb_pending = 0;
2660                         }
2661                 }
2662
2663         return 0;
2664         }
2665
2666 int
2667 tls1_heartbeat(SSL *s)
2668         {
2669         unsigned char *buf, *p;
2670         int ret;
2671         unsigned int payload = 18; /* Sequence number + random bytes */
2672         unsigned int padding = 16; /* Use minimum padding */
2673
2674         /* Only send if peer supports and accepts HB requests... */
2675         if (!(s->tlsext_heartbeat & SSL_TLSEXT_HB_ENABLED) ||
2676             s->tlsext_heartbeat & SSL_TLSEXT_HB_DONT_SEND_REQUESTS)
2677                 {
2678                 SSLerr(SSL_F_TLS1_HEARTBEAT,SSL_R_TLS_HEARTBEAT_PEER_DOESNT_ACCEPT);
2679                 return -1;
2680                 }
2681
2682         /* ...and there is none in flight yet... */
2683         if (s->tlsext_hb_pending)
2684                 {
2685                 SSLerr(SSL_F_TLS1_HEARTBEAT,SSL_R_TLS_HEARTBEAT_PENDING);
2686                 return -1;
2687                 }
2688
2689         /* ...and no handshake in progress. */
2690         if (SSL_in_init(s) || s->in_handshake)
2691                 {
2692                 SSLerr(SSL_F_TLS1_HEARTBEAT,SSL_R_UNEXPECTED_MESSAGE);
2693                 return -1;
2694                 }
2695
2696         /* Check if padding is too long, payload and padding
2697          * must not exceed 2^14 - 3 = 16381 bytes in total.
2698          */
2699         OPENSSL_assert(payload + padding <= 16381);
2700
2701         /* Create HeartBeat message, we just use a sequence number
2702          * as payload to distuingish different messages and add
2703          * some random stuff.
2704          *  - Message Type, 1 byte
2705          *  - Payload Length, 2 bytes (unsigned int)
2706          *  - Payload, the sequence number (2 bytes uint)
2707          *  - Payload, random bytes (16 bytes uint)
2708          *  - Padding
2709          */
2710         buf = OPENSSL_malloc(1 + 2 + payload + padding);
2711         p = buf;
2712         /* Message Type */
2713         *p++ = TLS1_HB_REQUEST;
2714         /* Payload length (18 bytes here) */
2715         s2n(payload, p);
2716         /* Sequence number */
2717         s2n(s->tlsext_hb_seq, p);
2718         /* 16 random bytes */
2719         RAND_pseudo_bytes(p, 16);
2720         p += 16;
2721         /* Random padding */
2722         RAND_pseudo_bytes(p, padding);
2723
2724         ret = ssl3_write_bytes(s, TLS1_RT_HEARTBEAT, buf, 3 + payload + padding);
2725         if (ret >= 0)
2726                 {
2727                 if (s->msg_callback)
2728                         s->msg_callback(1, s->version, TLS1_RT_HEARTBEAT,
2729                                 buf, 3 + payload + padding,
2730                                 s, s->msg_callback_arg);
2731
2732                 s->tlsext_hb_pending = 1;
2733                 }
2734
2735         OPENSSL_free(buf);
2736
2737         return ret;
2738         }
2739 #endif