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 # if 0
 133     {
 134      "SRTP_NULL_SHA1_80",
 135      SRTP_NULL_SHA1_80,
 136      },
 137     {
 138      "SRTP_NULL_SHA1_32",
 139      SRTP_NULL_SHA1_32,
 140      },
 141 # endif
 142     {0}
 143 };
 144
 145 static int find_profile_by_name(char *profile_name,
 146                                 SRTP_PROTECTION_PROFILE **pptr, unsigned len)
 147 {
 148     SRTP_PROTECTION_PROFILE *p;
 149
 150     p = srtp_known_profiles;
 151     while (p->name) {
 152         if ((len == strlen(p->name)) && !strncmp(p->name, profile_name, len)) {
 153             *pptr = p;
 154             return 0;
 155         }
 156
 157         p++;
 158     }
 159
 160     return 1;
 161 }
 162
 163 static int ssl_ctx_make_profiles(const char *profiles_string,
 164                                  STACK_OF(SRTP_PROTECTION_PROFILE) **out)
 165 {
 166     STACK_OF(SRTP_PROTECTION_PROFILE) *profiles;
 167
 168     char *col;
 169     char *ptr = (char *)profiles_string;
 170
 171     SRTP_PROTECTION_PROFILE *p;
 172
 173     if (!(profiles = sk_SRTP_PROTECTION_PROFILE_new_null())) {
 174         SSLerr(SSL_F_SSL_CTX_MAKE_PROFILES,
 175                SSL_R_SRTP_COULD_NOT_ALLOCATE_PROFILES);
 176         return 1;
 177     }
 178
 179     do {
 180         col = strchr(ptr, ':');
 181
 182         if (!find_profile_by_name(ptr, &p,
 183                                   col ? col - ptr : (int)strlen(ptr))) {
 184             if (sk_SRTP_PROTECTION_PROFILE_find(profiles, p) >= 0) {
 185                 SSLerr(SSL_F_SSL_CTX_MAKE_PROFILES,
 186                        SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 187                 sk_SRTP_PROTECTION_PROFILE_free(profiles);
 188                 return 1;
 189             }
 190
 191             sk_SRTP_PROTECTION_PROFILE_push(profiles, p);
 192         } else {
 193             SSLerr(SSL_F_SSL_CTX_MAKE_PROFILES,
 194                    SSL_R_SRTP_UNKNOWN_PROTECTION_PROFILE);
 195             sk_SRTP_PROTECTION_PROFILE_free(profiles);
 196             return 1;
 197         }
 198
 199         if (col)
 200             ptr = col + 1;
 201     } while (col);
 202
 203     *out = profiles;
 204
 205     return 0;
 206 }
 207
 208 int SSL_CTX_set_tlsext_use_srtp(SSL_CTX *ctx, const char *profiles)
 209 {
 210     return ssl_ctx_make_profiles(profiles, &ctx->srtp_profiles);
 211 }
 212
 213 int SSL_set_tlsext_use_srtp(SSL *s, const char *profiles)
 214 {
 215     return ssl_ctx_make_profiles(profiles, &s->srtp_profiles);
 216 }
 217
 218 STACK_OF(SRTP_PROTECTION_PROFILE) *SSL_get_srtp_profiles(SSL *s)
 219 {
 220     if (s != NULL) {
 221         if (s->srtp_profiles != NULL) {
 222             return s->srtp_profiles;
 223         } else if ((s->ctx != NULL) && (s->ctx->srtp_profiles != NULL)) {
 224             return s->ctx->srtp_profiles;
 225         }
 226     }
 227
 228     return NULL;
 229 }
 230
 231 SRTP_PROTECTION_PROFILE *SSL_get_selected_srtp_profile(SSL *s)
 232 {
 233     return s->srtp_profile;
 234 }
 235
 236 /*
 237  * Note: this function returns 0 length if there are no profiles specified
 238  */
 239 int ssl_add_clienthello_use_srtp_ext(SSL *s, unsigned char *p, int *len,
 240                                      int maxlen)
 241 {
 242     int ct = 0;
 243     int i;
 244     STACK_OF(SRTP_PROTECTION_PROFILE) *clnt = 0;
 245     SRTP_PROTECTION_PROFILE *prof;
 246
 247     clnt = SSL_get_srtp_profiles(s);
 248     ct = sk_SRTP_PROTECTION_PROFILE_num(clnt); /* -1 if clnt == 0 */
 249
 250     if (p) {
 251         if (ct == 0) {
 252             SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_USE_SRTP_EXT,
 253                    SSL_R_EMPTY_SRTP_PROTECTION_PROFILE_LIST);
 254             return 1;
 255         }
 256
 257         if ((2 + ct * 2 + 1) > maxlen) {
 258             SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_USE_SRTP_EXT,
 259                    SSL_R_SRTP_PROTECTION_PROFILE_LIST_TOO_LONG);
 260             return 1;
 261         }
 262
 263         /* Add the length */
 264         s2n(ct * 2, p);
 265         for (i = 0; i < ct; i++) {
 266             prof = sk_SRTP_PROTECTION_PROFILE_value(clnt, i);
 267             s2n(prof->id, p);
 268         }
 269
 270         /* Add an empty use_mki value */
 271         *p++ = 0;
 272     }
 273
 274     *len = 2 + ct * 2 + 1;
 275
 276     return 0;
 277 }
 278
 279 int ssl_parse_clienthello_use_srtp_ext(SSL *s, unsigned char *d, int len,
 280                                        int *al)
 281 {
 282     SRTP_PROTECTION_PROFILE *sprof;
 283     STACK_OF(SRTP_PROTECTION_PROFILE) *srvr;
 284     int ct;
 285     int mki_len;
 286     int i, srtp_pref;
 287     unsigned int id;
 288
 289     /* Length value + the MKI length */
 290     if (len < 3) {
 291         SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,
 292                SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 293         *al = SSL_AD_DECODE_ERROR;
 294         return 1;
 295     }
 296
 297     /* Pull off the length of the cipher suite list */
 298     n2s(d, ct);
 299     len -= 2;
 300
 301     /* Check that it is even */
 302     if (ct % 2) {
 303         SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,
 304                SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 305         *al = SSL_AD_DECODE_ERROR;
 306         return 1;
 307     }
 308
 309     /* Check that lengths are consistent */
 310     if (len < (ct + 1)) {
 311         SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,
 312                SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 313         *al = SSL_AD_DECODE_ERROR;
 314         return 1;
 315     }
 316
 317     srvr = SSL_get_srtp_profiles(s);
 318     s->srtp_profile = NULL;
 319     /* Search all profiles for a match initially */
 320     srtp_pref = sk_SRTP_PROTECTION_PROFILE_num(srvr);
 321
 322     while (ct) {
 323         n2s(d, id);
 324         ct -= 2;
 325         len -= 2;
 326
 327         /*
 328          * Only look for match in profiles of higher preference than
 329          * current match.
 330          * If no profiles have been have been configured then this
 331          * does nothing.
 332          */
 333         for (i = 0; i < srtp_pref; i++) {
 334             sprof = sk_SRTP_PROTECTION_PROFILE_value(srvr, i);
 335             if (sprof->id == id) {
 336                 s->srtp_profile = sprof;
 337                 srtp_pref = i;
 338                 break;
 339             }
 340         }
 341     }
 342
 343     /*
 344      * Now extract the MKI value as a sanity check, but discard it for now
 345      */
 346     mki_len = *d;
 347     d++;
 348     len--;
 349
 350     if (mki_len != len) {
 351         SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,
 352                SSL_R_BAD_SRTP_MKI_VALUE);
 353         *al = SSL_AD_DECODE_ERROR;
 354         return 1;
 355     }
 356
 357     return 0;
 358 }
 359
 360 int ssl_add_serverhello_use_srtp_ext(SSL *s, unsigned char *p, int *len,
 361                                      int maxlen)
 362 {
 363     if (p) {
 364         if (maxlen < 5) {
 365             SSLerr(SSL_F_SSL_ADD_SERVERHELLO_USE_SRTP_EXT,
 366                    SSL_R_SRTP_PROTECTION_PROFILE_LIST_TOO_LONG);
 367             return 1;
 368         }
 369
 370         if (s->srtp_profile == 0) {
 371             SSLerr(SSL_F_SSL_ADD_SERVERHELLO_USE_SRTP_EXT,
 372                    SSL_R_USE_SRTP_NOT_NEGOTIATED);
 373             return 1;
 374         }
 375         s2n(2, p);
 376         s2n(s->srtp_profile->id, p);
 377         *p++ = 0;
 378     }
 379     *len = 5;
 380
 381     return 0;
 382 }
 383
 384 int ssl_parse_serverhello_use_srtp_ext(SSL *s, unsigned char *d, int len,
 385                                        int *al)
 386 {
 387     unsigned id;
 388     int i;
 389     int ct;
 390
 391     STACK_OF(SRTP_PROTECTION_PROFILE) *clnt;
 392     SRTP_PROTECTION_PROFILE *prof;
 393
 394     if (len != 5) {
 395         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
 396                SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 397         *al = SSL_AD_DECODE_ERROR;
 398         return 1;
 399     }
 400
 401     n2s(d, ct);
 402     if (ct != 2) {
 403         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
 404                SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 405         *al = SSL_AD_DECODE_ERROR;
 406         return 1;
 407     }
 408
 409     n2s(d, id);
 410     if (*d) {                   /* Must be no MKI, since we never offer one */
 411         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
 412                SSL_R_BAD_SRTP_MKI_VALUE);
 413         *al = SSL_AD_ILLEGAL_PARAMETER;
 414         return 1;
 415     }
 416
 417     clnt = SSL_get_srtp_profiles(s);
 418
 419     /* Throw an error if the server gave us an unsolicited extension */
 420     if (clnt == NULL) {
 421         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
 422                SSL_R_NO_SRTP_PROFILES);
 423         *al = SSL_AD_DECODE_ERROR;
 424         return 1;
 425     }
 426
 427     /*
 428      * Check to see if the server gave us something we support (and
 429      * presumably offered)
 430      */
 431     for (i = 0; i < sk_SRTP_PROTECTION_PROFILE_num(clnt); i++) {
 432         prof = sk_SRTP_PROTECTION_PROFILE_value(clnt, i);
 433
 434         if (prof->id == id) {
 435             s->srtp_profile = prof;
 436             *al = 0;
 437             return 0;
 438         }
 439     }
 440
 441     SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
 442            SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 443     *al = SSL_AD_DECODE_ERROR;
 444     return 1;
 445 }
 446
 447 #endif