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 #include "srtp.h"
 121
 122 #ifndef OPENSSL_NO_SRTP
 123
 124 static SRTP_PROTECTION_PROFILE srtp_known_profiles[] = {
 125     {
 126      "SRTP_AES128_CM_SHA1_80",
 127      SRTP_AES128_CM_SHA1_80,
 128      },
 129     {
 130      "SRTP_AES128_CM_SHA1_32",
 131      SRTP_AES128_CM_SHA1_32,
 132      },
 133 # if 0
 134     {
 135      "SRTP_NULL_SHA1_80",
 136      SRTP_NULL_SHA1_80,
 137      },
 138     {
 139      "SRTP_NULL_SHA1_32",
 140      SRTP_NULL_SHA1_32,
 141      },
 142 # endif
 143     {0}
 144 };
 145
 146 static int find_profile_by_name(char *profile_name,
 147                                 SRTP_PROTECTION_PROFILE **pptr, unsigned len)
 148 {
 149     SRTP_PROTECTION_PROFILE *p;
 150
 151     p = srtp_known_profiles;
 152     while (p->name) {
 153         if ((len == strlen(p->name)) && !strncmp(p->name, profile_name, len)) {
 154             *pptr = p;
 155             return 0;
 156         }
 157
 158         p++;
 159     }
 160
 161     return 1;
 162 }
 163
 164 static int ssl_ctx_make_profiles(const char *profiles_string,
 165                                  STACK_OF(SRTP_PROTECTION_PROFILE) **out)
 166 {
 167     STACK_OF(SRTP_PROTECTION_PROFILE) *profiles;
 168
 169     char *col;
 170     char *ptr = (char *)profiles_string;
 171
 172     SRTP_PROTECTION_PROFILE *p;
 173
 174     if (!(profiles = sk_SRTP_PROTECTION_PROFILE_new_null())) {
 175         SSLerr(SSL_F_SSL_CTX_MAKE_PROFILES,
 176                SSL_R_SRTP_COULD_NOT_ALLOCATE_PROFILES);
 177         return 1;
 178     }
 179
 180     do {
 181         col = strchr(ptr, ':');
 182
 183         if (!find_profile_by_name(ptr, &p,
 184                                   col ? col - ptr : (int)strlen(ptr))) {
 185             if (sk_SRTP_PROTECTION_PROFILE_find(profiles, p) >= 0) {
 186                 SSLerr(SSL_F_SSL_CTX_MAKE_PROFILES,
 187                        SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 188                 sk_SRTP_PROTECTION_PROFILE_free(profiles);
 189                 return 1;
 190             }
 191
 192             sk_SRTP_PROTECTION_PROFILE_push(profiles, p);
 193         } else {
 194             SSLerr(SSL_F_SSL_CTX_MAKE_PROFILES,
 195                    SSL_R_SRTP_UNKNOWN_PROTECTION_PROFILE);
 196             sk_SRTP_PROTECTION_PROFILE_free(profiles);
 197             return 1;
 198         }
 199
 200         if (col)
 201             ptr = col + 1;
 202     } while (col);
 203
 204     *out = profiles;
 205
 206     return 0;
 207 }
 208
 209 int SSL_CTX_set_tlsext_use_srtp(SSL_CTX *ctx, const char *profiles)
 210 {
 211     return ssl_ctx_make_profiles(profiles, &ctx->srtp_profiles);
 212 }
 213
 214 int SSL_set_tlsext_use_srtp(SSL *s, const char *profiles)
 215 {
 216     return ssl_ctx_make_profiles(profiles, &s->srtp_profiles);
 217 }
 218
 219 STACK_OF(SRTP_PROTECTION_PROFILE) *SSL_get_srtp_profiles(SSL *s)
 220 {
 221     if (s != NULL) {
 222         if (s->srtp_profiles != NULL) {
 223             return s->srtp_profiles;
 224         } else if ((s->ctx != NULL) && (s->ctx->srtp_profiles != NULL)) {
 225             return s->ctx->srtp_profiles;
 226         }
 227     }
 228
 229     return NULL;
 230 }
 231
 232 SRTP_PROTECTION_PROFILE *SSL_get_selected_srtp_profile(SSL *s)
 233 {
 234     return s->srtp_profile;
 235 }
 236
 237 /*
 238  * Note: this function returns 0 length if there are no profiles specified
 239  */
 240 int ssl_add_clienthello_use_srtp_ext(SSL *s, unsigned char *p, int *len,
 241                                      int maxlen)
 242 {
 243     int ct = 0;
 244     int i;
 245     STACK_OF(SRTP_PROTECTION_PROFILE) *clnt = 0;
 246     SRTP_PROTECTION_PROFILE *prof;
 247
 248     clnt = SSL_get_srtp_profiles(s);
 249     ct = sk_SRTP_PROTECTION_PROFILE_num(clnt); /* -1 if clnt == 0 */
 250
 251     if (p) {
 252         if (ct == 0) {
 253             SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_USE_SRTP_EXT,
 254                    SSL_R_EMPTY_SRTP_PROTECTION_PROFILE_LIST);
 255             return 1;
 256         }
 257
 258         if ((2 + ct * 2 + 1) > maxlen) {
 259             SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_USE_SRTP_EXT,
 260                    SSL_R_SRTP_PROTECTION_PROFILE_LIST_TOO_LONG);
 261             return 1;
 262         }
 263
 264         /* Add the length */
 265         s2n(ct * 2, p);
 266         for (i = 0; i < ct; i++) {
 267             prof = sk_SRTP_PROTECTION_PROFILE_value(clnt, i);
 268             s2n(prof->id, p);
 269         }
 270
 271         /* Add an empty use_mki value */
 272         *p++ = 0;
 273     }
 274
 275     *len = 2 + ct * 2 + 1;
 276
 277     return 0;
 278 }
 279
 280 int ssl_parse_clienthello_use_srtp_ext(SSL *s, unsigned char *d, int len,
 281                                        int *al)
 282 {
 283     SRTP_PROTECTION_PROFILE *sprof;
 284     STACK_OF(SRTP_PROTECTION_PROFILE) *srvr;
 285     int ct;
 286     int mki_len;
 287     int i, srtp_pref;
 288     unsigned int id;
 289
 290     /* Length value + the MKI length */
 291     if (len < 3) {
 292         SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,
 293                SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 294         *al = SSL_AD_DECODE_ERROR;
 295         return 1;
 296     }
 297
 298     /* Pull off the length of the cipher suite list */
 299     n2s(d, ct);
 300     len -= 2;
 301
 302     /* Check that it is even */
 303     if (ct % 2) {
 304         SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,
 305                SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 306         *al = SSL_AD_DECODE_ERROR;
 307         return 1;
 308     }
 309
 310     /* Check that lengths are consistent */
 311     if (len < (ct + 1)) {
 312         SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,
 313                SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 314         *al = SSL_AD_DECODE_ERROR;
 315         return 1;
 316     }
 317
 318     srvr = SSL_get_srtp_profiles(s);
 319     s->srtp_profile = NULL;
 320     /* Search all profiles for a match initially */
 321     srtp_pref = sk_SRTP_PROTECTION_PROFILE_num(srvr);
 322
 323     while (ct) {
 324         n2s(d, id);
 325         ct -= 2;
 326         len -= 2;
 327
 328         /*
 329          * Only look for match in profiles of higher preference than
 330          * current match.
 331          * If no profiles have been have been configured then this
 332          * does nothing.
 333          */
 334         for (i = 0; i < srtp_pref; i++) {
 335             sprof = sk_SRTP_PROTECTION_PROFILE_value(srvr, i);
 336             if (sprof->id == id) {
 337                 s->srtp_profile = sprof;
 338                 srtp_pref = i;
 339                 break;
 340             }
 341         }
 342     }
 343
 344     /*
 345      * Now extract the MKI value as a sanity check, but discard it for now
 346      */
 347     mki_len = *d;
 348     d++;
 349     len--;
 350
 351     if (mki_len != len) {
 352         SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,
 353                SSL_R_BAD_SRTP_MKI_VALUE);
 354         *al = SSL_AD_DECODE_ERROR;
 355         return 1;
 356     }
 357
 358     return 0;
 359 }
 360
 361 int ssl_add_serverhello_use_srtp_ext(SSL *s, unsigned char *p, int *len,
 362                                      int maxlen)
 363 {
 364     if (p) {
 365         if (maxlen < 5) {
 366             SSLerr(SSL_F_SSL_ADD_SERVERHELLO_USE_SRTP_EXT,
 367                    SSL_R_SRTP_PROTECTION_PROFILE_LIST_TOO_LONG);
 368             return 1;
 369         }
 370
 371         if (s->srtp_profile == 0) {
 372             SSLerr(SSL_F_SSL_ADD_SERVERHELLO_USE_SRTP_EXT,
 373                    SSL_R_USE_SRTP_NOT_NEGOTIATED);
 374             return 1;
 375         }
 376         s2n(2, p);
 377         s2n(s->srtp_profile->id, p);
 378         *p++ = 0;
 379     }
 380     *len = 5;
 381
 382     return 0;
 383 }
 384
 385 int ssl_parse_serverhello_use_srtp_ext(SSL *s, unsigned char *d, int len,
 386                                        int *al)
 387 {
 388     unsigned id;
 389     int i;
 390     int ct;
 391
 392     STACK_OF(SRTP_PROTECTION_PROFILE) *clnt;
 393     SRTP_PROTECTION_PROFILE *prof;
 394
 395     if (len != 5) {
 396         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
 397                SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 398         *al = SSL_AD_DECODE_ERROR;
 399         return 1;
 400     }
 401
 402     n2s(d, ct);
 403     if (ct != 2) {
 404         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
 405                SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 406         *al = SSL_AD_DECODE_ERROR;
 407         return 1;
 408     }
 409
 410     n2s(d, id);
 411     if (*d) {                   /* Must be no MKI, since we never offer one */
 412         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
 413                SSL_R_BAD_SRTP_MKI_VALUE);
 414         *al = SSL_AD_ILLEGAL_PARAMETER;
 415         return 1;
 416     }
 417
 418     clnt = SSL_get_srtp_profiles(s);
 419
 420     /* Throw an error if the server gave us an unsolicited extension */
 421     if (clnt == NULL) {
 422         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
 423                SSL_R_NO_SRTP_PROFILES);
 424         *al = SSL_AD_DECODE_ERROR;
 425         return 1;
 426     }
 427
 428     /*
 429      * Check to see if the server gave us something we support (and
 430      * presumably offered)
 431      */
 432     for (i = 0; i < sk_SRTP_PROTECTION_PROFILE_num(clnt); i++) {
 433         prof = sk_SRTP_PROTECTION_PROFILE_value(clnt, i);
 434
 435         if (prof->id == id) {
 436             s->srtp_profile = prof;
 437             *al = 0;
 438             return 0;
 439         }
 440     }
 441
 442     SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
 443            SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
 444     *al = SSL_AD_DECODE_ERROR;
 445     return 1;
 446 }
 447
 448 #endif