ssl/d1_srtp.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) 1998-2006 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  * DTLS code by Eric Rescorla <ekr@rtfm.com>
 113  *
 114  * Copyright (C) 2006, Network Resonance, Inc. Copyright (C) 2011, RTFM, Inc.
 115  */
 116
 117 #include <stdio.h>
 118 #include <openssl/objects.h>
 119 #include "ssl_locl.h"
 120
 121 #ifndef OPENSSL_NO_SRTP
 122
 123 static SRTP_PROTECTION_PROFILE srtp_known_profiles[] = {
 124     {
 125      "SRTP_AES128_CM_SHA1_80",
 126      SRTP_AES128_CM_SHA1_80,
 127      },
 128     {
 129      "SRTP_AES128_CM_SHA1_32",
 130      SRTP_AES128_CM_SHA1_32,
 131      },
 132     {0}
 133 };
 134
 135 static int find_profile_by_name(char *profile_name,
 136                                 SRTP_PROTECTION_PROFILE **pptr, unsigned len)
 137 {
 138     SRTP_PROTECTION_PROFILE *p;
 139
 140     p = srtp_known_profiles;
 141     while (p->name) {
 142         if ((len == strlen(p->name))
 143             && strncmp(p->name, profile_name, len) == 0) {
 144             *pptr = p;
 145             return 0;
 146         }
 147
 148         p++;
 149     }
 150
 151     return 1;
 152 }
 153
 154 static int ssl_ctx_make_profiles(const char *profiles_string,
 155                                  STACK_OF(SRTP_PROTECTION_PROFILE) **out)
 156 {
 157     STACK_OF(SRTP_PROTECTION_PROFILE) *profiles;
 158
 159     char *col;
 160     char *ptr = (char *)profiles_string;
 161     SRTP_PROTECTION_PROFILE *p;
 162
 163     if (!(profiles = sk_SRTP_PROTECTION_PROFILE_new_null())) {
 164         SSLerr(SSL_F_SSL_CTX_MAKE_PROFILES,
 165                SSL_R_SRTP_COULD_NOT_ALLOCATE_PROFILES);
 166         return 1;
 167     }
 168
 169     do {
 170         col = strchr(ptr, ':');
 171
 172         if (!find_profile_by_name(ptr, &p,
 173                                   col ? col - ptr : (int)strlen(ptr))) {
 174             if (sk_SRTP_PROTECTION_PROFILE_find(profiles, p) >= 0) {
 175                 SSLerr(SSL_F_SSL_CTX_MAKE_PROFILES,
 176                        SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 177                 sk_SRTP_PROTECTION_PROFILE_free(profiles);
 178                 return 1;
 179             }
 180
 181             sk_SRTP_PROTECTION_PROFILE_push(profiles, p);
 182         } else {
 183             SSLerr(SSL_F_SSL_CTX_MAKE_PROFILES,
 184                    SSL_R_SRTP_UNKNOWN_PROTECTION_PROFILE);
 185             sk_SRTP_PROTECTION_PROFILE_free(profiles);
 186             return 1;
 187         }
 188
 189         if (col)
 190             ptr = col + 1;
 191     } while (col);
 192
 193     *out = profiles;
 194
 195     return 0;
 196 }
 197
 198 int SSL_CTX_set_tlsext_use_srtp(SSL_CTX *ctx, const char *profiles)
 199 {
 200     return ssl_ctx_make_profiles(profiles, &ctx->srtp_profiles);
 201 }
 202
 203 int SSL_set_tlsext_use_srtp(SSL *s, const char *profiles)
 204 {
 205     return ssl_ctx_make_profiles(profiles, &s->srtp_profiles);
 206 }
 207
 208 STACK_OF(SRTP_PROTECTION_PROFILE) *SSL_get_srtp_profiles(SSL *s)
 209 {
 210     if (s != NULL) {
 211         if (s->srtp_profiles != NULL) {
 212             return s->srtp_profiles;
 213         } else if ((s->ctx != NULL) && (s->ctx->srtp_profiles != NULL)) {
 214             return s->ctx->srtp_profiles;
 215         }
 216     }
 217
 218     return NULL;
 219 }
 220
 221 SRTP_PROTECTION_PROFILE *SSL_get_selected_srtp_profile(SSL *s)
 222 {
 223     return s->srtp_profile;
 224 }
 225
 226 /*
 227  * Note: this function returns 0 length if there are no profiles specified
 228  */
 229 int ssl_add_clienthello_use_srtp_ext(SSL *s, unsigned char *p, int *len,
 230                                      int maxlen)
 231 {
 232     int ct = 0;
 233     int i;
 234     STACK_OF(SRTP_PROTECTION_PROFILE) *clnt = 0;
 235     SRTP_PROTECTION_PROFILE *prof;
 236
 237     clnt = SSL_get_srtp_profiles(s);
 238     ct = sk_SRTP_PROTECTION_PROFILE_num(clnt); /* -1 if clnt == 0 */
 239
 240     if (p) {
 241         if (ct == 0) {
 242             SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_USE_SRTP_EXT,
 243                    SSL_R_EMPTY_SRTP_PROTECTION_PROFILE_LIST);
 244             return 1;
 245         }
 246
 247         if ((2 + ct * 2 + 1) > maxlen) {
 248             SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_USE_SRTP_EXT,
 249                    SSL_R_SRTP_PROTECTION_PROFILE_LIST_TOO_LONG);
 250             return 1;
 251         }
 252
 253         /* Add the length */
 254         s2n(ct * 2, p);
 255         for (i = 0; i < ct; i++) {
 256             prof = sk_SRTP_PROTECTION_PROFILE_value(clnt, i);
 257             s2n(prof->id, p);
 258         }
 259
 260         /* Add an empty use_mki value */
 261         *p++ = 0;
 262     }
 263
 264     *len = 2 + ct * 2 + 1;
 265
 266     return 0;
 267 }
 268
 269 int ssl_parse_clienthello_use_srtp_ext(SSL *s, unsigned char *d, int len,
 270                                        int *al)
 271 {
 272     SRTP_PROTECTION_PROFILE *sprof;
 273     STACK_OF(SRTP_PROTECTION_PROFILE) *srvr;
 274     int ct;
 275     int mki_len;
 276     int i, srtp_pref;
 277     unsigned int id;
 278
 279     /* Length value + the MKI length */
 280     if (len < 3) {
 281         SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,
 282                SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 283         *al = SSL_AD_DECODE_ERROR;
 284         return 1;
 285     }
 286
 287     /* Pull off the length of the cipher suite list */
 288     n2s(d, ct);
 289     len -= 2;
 290
 291     /* Check that it is even */
 292     if (ct % 2) {
 293         SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,
 294                SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 295         *al = SSL_AD_DECODE_ERROR;
 296         return 1;
 297     }
 298
 299     /* Check that lengths are consistent */
 300     if (len < (ct + 1)) {
 301         SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,
 302                SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 303         *al = SSL_AD_DECODE_ERROR;
 304         return 1;
 305     }
 306
 307     srvr = SSL_get_srtp_profiles(s);
 308     s->srtp_profile = NULL;
 309     /* Search all profiles for a match initially */
 310     srtp_pref = sk_SRTP_PROTECTION_PROFILE_num(srvr);
 311
 312     while (ct) {
 313         n2s(d, id);
 314         ct -= 2;
 315         len -= 2;
 316
 317         /*
 318          * Only look for match in profiles of higher preference than
 319          * current match.
 320          * If no profiles have been have been configured then this
 321          * does nothing.
 322          */
 323         for (i = 0; i < srtp_pref; i++) {
 324             sprof = sk_SRTP_PROTECTION_PROFILE_value(srvr, i);
 325             if (sprof->id == id) {
 326                 s->srtp_profile = sprof;
 327                 srtp_pref = i;
 328                 break;
 329             }
 330         }
 331     }
 332
 333     /*
 334      * Now extract the MKI value as a sanity check, but discard it for now
 335      */
 336     mki_len = *d;
 337     d++;
 338     len--;
 339
 340     if (mki_len != len) {
 341         SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,
 342                SSL_R_BAD_SRTP_MKI_VALUE);
 343         *al = SSL_AD_DECODE_ERROR;
 344         return 1;
 345     }
 346
 347     return 0;
 348 }
 349
 350 int ssl_add_serverhello_use_srtp_ext(SSL *s, unsigned char *p, int *len,
 351                                      int maxlen)
 352 {
 353     if (p) {
 354         if (maxlen < 5) {
 355             SSLerr(SSL_F_SSL_ADD_SERVERHELLO_USE_SRTP_EXT,
 356                    SSL_R_SRTP_PROTECTION_PROFILE_LIST_TOO_LONG);
 357             return 1;
 358         }
 359
 360         if (s->srtp_profile == 0) {
 361             SSLerr(SSL_F_SSL_ADD_SERVERHELLO_USE_SRTP_EXT,
 362                    SSL_R_USE_SRTP_NOT_NEGOTIATED);
 363             return 1;
 364         }
 365         s2n(2, p);
 366         s2n(s->srtp_profile->id, p);
 367         *p++ = 0;
 368     }
 369     *len = 5;
 370
 371     return 0;
 372 }
 373
 374 int ssl_parse_serverhello_use_srtp_ext(SSL *s, unsigned char *d, int len,
 375                                        int *al)
 376 {
 377     unsigned id;
 378     int i;
 379     int ct;
 380
 381     STACK_OF(SRTP_PROTECTION_PROFILE) *clnt;
 382     SRTP_PROTECTION_PROFILE *prof;
 383
 384     if (len != 5) {
 385         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
 386                SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 387         *al = SSL_AD_DECODE_ERROR;
 388         return 1;
 389     }
 390
 391     n2s(d, ct);
 392     if (ct != 2) {
 393         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
 394                SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 395         *al = SSL_AD_DECODE_ERROR;
 396         return 1;
 397     }
 398
 399     n2s(d, id);
 400     if (*d) {                   /* Must be no MKI, since we never offer one */
 401         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
 402                SSL_R_BAD_SRTP_MKI_VALUE);
 403         *al = SSL_AD_ILLEGAL_PARAMETER;
 404         return 1;
 405     }
 406
 407     clnt = SSL_get_srtp_profiles(s);
 408
 409     /* Throw an error if the server gave us an unsolicited extension */
 410     if (clnt == NULL) {
 411         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
 412                SSL_R_NO_SRTP_PROFILES);
 413         *al = SSL_AD_DECODE_ERROR;
 414         return 1;
 415     }
 416
 417     /*
 418      * Check to see if the server gave us something we support (and
 419      * presumably offered)
 420      */
 421     for (i = 0; i < sk_SRTP_PROTECTION_PROFILE_num(clnt); i++) {
 422         prof = sk_SRTP_PROTECTION_PROFILE_value(clnt, i);
 423
 424         if (prof->id == id) {
 425             s->srtp_profile = prof;
 426             *al = 0;
 427             return 0;
 428         }
 429     }
 430
 431     SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
 432            SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 433     *al = SSL_AD_DECODE_ERROR;
 434     return 1;
 435 }
 436
 437 #endif