1 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com) 2 * All rights reserved. 3 * 4 * This package is an SSL implementation written 5 * by Eric Young (eay (at) cryptsoft.com). 6 * The implementation was written so as to conform with Netscapes SSL. 7 * 8 * This library is free for commercial and non-commercial use as long as 9 * the following conditions are aheared to. The following conditions 10 * apply to all code found in this distribution, be it the RC4, RSA, 11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 12 * included with this distribution is covered by the same copyright terms 13 * except that the holder is Tim Hudson (tjh (at) cryptsoft.com). 14 * 15 * Copyright remains Eric Young's, and as such any Copyright notices in 16 * the code are not to be removed. 17 * If this package is used in a product, Eric Young should be given attribution 18 * as the author of the parts of the library used. 19 * This can be in the form of a textual message at program startup or 20 * in documentation (online or textual) provided with the package. 21 * 22 * Redistribution and use in source and binary forms, with or without 23 * modification, are permitted provided that the following conditions 24 * are met: 25 * 1. Redistributions of source code must retain the copyright 26 * notice, this list of conditions and the following disclaimer. 27 * 2. Redistributions in binary form must reproduce the above copyright 28 * notice, this list of conditions and the following disclaimer in the 29 * documentation and/or other materials provided with the distribution. 30 * 3. All advertising materials mentioning features or use of this software 31 * must display the following acknowledgement: 32 * "This product includes cryptographic software written by 33 * Eric Young (eay (at) cryptsoft.com)" 34 * The word 'cryptographic' can be left out if the rouines from the library 35 * being used are not cryptographic related :-). 36 * 4. If you include any Windows specific code (or a derivative thereof) from 37 * the apps directory (application code) you must include an acknowledgement: 38 * "This product includes software written by Tim Hudson (tjh (at) cryptsoft.com)" 39 * 40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 50 * SUCH DAMAGE. 51 * 52 * The licence and distribution terms for any publically available version or 53 * derivative of this code cannot be changed. i.e. this code cannot simply be 54 * copied and put under another distribution licence 55 * [including the GNU Public Licence.] 56 */ 57 /* ==================================================================== 58 * Copyright (c) 1998-2006 The OpenSSL Project. All rights reserved. 59 * 60 * Redistribution and use in source and binary forms, with or without 61 * modification, are permitted provided that the following conditions 62 * are met: 63 * 64 * 1. Redistributions of source code must retain the above copyright 65 * notice, this list of conditions and the following disclaimer. 66 * 67 * 2. Redistributions in binary form must reproduce the above copyright 68 * notice, this list of conditions and the following disclaimer in 69 * the documentation and/or other materials provided with the 70 * distribution. 71 * 72 * 3. All advertising materials mentioning features or use of this 73 * software must display the following acknowledgment: 74 * "This product includes software developed by the OpenSSL Project 75 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 76 * 77 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 78 * endorse or promote products derived from this software without 79 * prior written permission. For written permission, please contact 80 * openssl-core (at) openssl.org. 81 * 82 * 5. Products derived from this software may not be called "OpenSSL" 83 * nor may "OpenSSL" appear in their names without prior written 84 * permission of the OpenSSL Project. 85 * 86 * 6. Redistributions of any form whatsoever must retain the following 87 * acknowledgment: 88 * "This product includes software developed by the OpenSSL Project 89 * for use in the OpenSSL Toolkit (http://www.openssl.org/)" 90 * 91 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 92 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 93 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 94 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 95 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 96 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 97 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 98 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 99 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 100 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 101 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 102 * OF THE POSSIBILITY OF SUCH DAMAGE. 103 * ==================================================================== 104 * 105 * This product includes cryptographic software written by Eric Young 106 * (eay (at) cryptsoft.com). This product includes software written by Tim 107 * Hudson (tjh (at) cryptsoft.com). 108 * 109 */ 110 /* 111 DTLS code by Eric Rescorla <ekr (at) rtfm.com> 112 113 Copyright (C) 2006, Network Resonance, Inc. 114 Copyright (C) 2011, RTFM, Inc. 115 */ 116 117 #include <stdio.h> 118 #include <string.h> 119 120 #include <openssl/bytestring.h> 121 #include <openssl/err.h> 122 #include <openssl/obj.h> 123 124 #include "internal.h" 125 #include <openssl/srtp.h> 126 127 128 static const SRTP_PROTECTION_PROFILE srtp_known_profiles[] = { 129 { 130 "SRTP_AES128_CM_SHA1_80", SRTP_AES128_CM_SHA1_80, 131 }, 132 { 133 "SRTP_AES128_CM_SHA1_32", SRTP_AES128_CM_SHA1_32, 134 }, 135 {0}, 136 }; 137 138 static int find_profile_by_name(const char *profile_name, 139 const SRTP_PROTECTION_PROFILE **pptr, 140 size_t len) { 141 const SRTP_PROTECTION_PROFILE *p; 142 143 p = srtp_known_profiles; 144 while (p->name) { 145 if (len == strlen(p->name) && !strncmp(p->name, profile_name, len)) { 146 *pptr = p; 147 return 1; 148 } 149 150 p++; 151 } 152 153 return 0; 154 } 155 156 static int find_profile_by_num(unsigned profile_num, 157 const SRTP_PROTECTION_PROFILE **pptr) { 158 const SRTP_PROTECTION_PROFILE *p; 159 160 p = srtp_known_profiles; 161 while (p->name) { 162 if (p->id == profile_num) { 163 *pptr = p; 164 return 1; 165 } 166 p++; 167 } 168 169 return 0; 170 } 171 172 static int ssl_ctx_make_profiles(const char *profiles_string, 173 STACK_OF(SRTP_PROTECTION_PROFILE) **out) { 174 STACK_OF(SRTP_PROTECTION_PROFILE) *profiles; 175 176 const char *col; 177 const char *ptr = profiles_string; 178 179 profiles = sk_SRTP_PROTECTION_PROFILE_new_null(); 180 if (profiles == NULL) { 181 OPENSSL_PUT_ERROR(SSL, ssl_ctx_make_profiles, 182 SSL_R_SRTP_COULD_NOT_ALLOCATE_PROFILES); 183 return 0; 184 } 185 186 do { 187 const SRTP_PROTECTION_PROFILE *p; 188 189 col = strchr(ptr, ':'); 190 if (find_profile_by_name(ptr, &p, col ? col - ptr : strlen(ptr))) { 191 sk_SRTP_PROTECTION_PROFILE_push(profiles, p); 192 } else { 193 OPENSSL_PUT_ERROR(SSL, ssl_ctx_make_profiles, 194 SSL_R_SRTP_UNKNOWN_PROTECTION_PROFILE); 195 return 0; 196 } 197 198 if (col) { 199 ptr = col + 1; 200 } 201 } while (col); 202 203 *out = profiles; 204 205 return 1; 206 } 207 208 int SSL_CTX_set_srtp_profiles(SSL_CTX *ctx, const char *profiles) { 209 return ssl_ctx_make_profiles(profiles, &ctx->srtp_profiles); 210 } 211 212 int SSL_set_srtp_profiles(SSL *s, const char *profiles) { 213 return ssl_ctx_make_profiles(profiles, &s->srtp_profiles); 214 } 215 216 STACK_OF(SRTP_PROTECTION_PROFILE) *SSL_get_srtp_profiles(SSL *s) { 217 if (s == NULL) { 218 return NULL; 219 } 220 221 if (s->srtp_profiles != NULL) { 222 return s->srtp_profiles; 223 } 224 225 if (s->ctx != NULL && s->ctx->srtp_profiles != NULL) { 226 return s->ctx->srtp_profiles; 227 } 228 229 return NULL; 230 } 231 232 const SRTP_PROTECTION_PROFILE *SSL_get_selected_srtp_profile(SSL *s) { 233 return s->srtp_profile; 234 } 235 236 int SSL_CTX_set_tlsext_use_srtp(SSL_CTX *ctx, const char *profiles) { 237 /* This API inverts its return value. */ 238 return !SSL_CTX_set_srtp_profiles(ctx, profiles); 239 } 240 241 int SSL_set_tlsext_use_srtp(SSL *s, const char *profiles) { 242 /* This API inverts its return value. */ 243 return !SSL_set_srtp_profiles(s, profiles); 244 } 245 246 /* Note: this function returns 0 length if there are no profiles specified */ 247 int ssl_add_clienthello_use_srtp_ext(SSL *s, uint8_t *p, int *len, int maxlen) { 248 int ct = 0; 249 int i; 250 STACK_OF(SRTP_PROTECTION_PROFILE) *clnt = 0; 251 const SRTP_PROTECTION_PROFILE *prof; 252 253 clnt = SSL_get_srtp_profiles(s); 254 ct = sk_SRTP_PROTECTION_PROFILE_num(clnt); /* -1 if clnt == 0 */ 255 256 if (p) { 257 if (ct == 0) { 258 OPENSSL_PUT_ERROR(SSL, ssl_add_clienthello_use_srtp_ext, 259 SSL_R_EMPTY_SRTP_PROTECTION_PROFILE_LIST); 260 return 0; 261 } 262 263 if (2 + ct * 2 + 1 > maxlen) { 264 OPENSSL_PUT_ERROR(SSL, ssl_add_clienthello_use_srtp_ext, 265 SSL_R_SRTP_PROTECTION_PROFILE_LIST_TOO_LONG); 266 return 0; 267 } 268 269 /* Add the length */ 270 s2n(ct * 2, p); 271 for (i = 0; i < ct; i++) { 272 prof = sk_SRTP_PROTECTION_PROFILE_value(clnt, i); 273 s2n(prof->id, p); 274 } 275 276 /* Add an empty use_mki value */ 277 *p++ = 0; 278 } 279 280 *len = 2 + ct * 2 + 1; 281 282 return 1; 283 } 284 285 int ssl_parse_clienthello_use_srtp_ext(SSL *s, CBS *cbs, int *out_alert) { 286 CBS profile_ids, srtp_mki; 287 const SRTP_PROTECTION_PROFILE *cprof, *sprof; 288 STACK_OF(SRTP_PROTECTION_PROFILE) *client_profiles = 0, *server_profiles; 289 size_t i, j; 290 int ret = 0; 291 292 if (!CBS_get_u16_length_prefixed(cbs, &profile_ids) || 293 CBS_len(&profile_ids) < 2 || 294 !CBS_get_u8_length_prefixed(cbs, &srtp_mki) || 295 CBS_len(cbs) != 0) { 296 OPENSSL_PUT_ERROR(SSL, ssl_parse_clienthello_use_srtp_ext, 297 SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST); 298 *out_alert = SSL_AD_DECODE_ERROR; 299 goto done; 300 } 301 302 client_profiles = sk_SRTP_PROTECTION_PROFILE_new_null(); 303 if (client_profiles == NULL) { 304 OPENSSL_PUT_ERROR(SSL, ssl_parse_clienthello_use_srtp_ext, 305 ERR_R_MALLOC_FAILURE); 306 *out_alert = SSL_AD_INTERNAL_ERROR; 307 goto done; 308 } 309 310 while (CBS_len(&profile_ids) > 0) { 311 uint16_t profile_id; 312 313 if (!CBS_get_u16(&profile_ids, &profile_id)) { 314 *out_alert = SSL_AD_DECODE_ERROR; 315 goto done; 316 } 317 318 if (find_profile_by_num(profile_id, &cprof)) { 319 sk_SRTP_PROTECTION_PROFILE_push(client_profiles, cprof); 320 } 321 } 322 323 /* Discard the MKI value for now. */ 324 325 server_profiles = SSL_get_srtp_profiles(s); 326 327 /* Pick the server's most preferred profile. */ 328 for (i = 0; i < sk_SRTP_PROTECTION_PROFILE_num(server_profiles); i++) { 329 sprof = sk_SRTP_PROTECTION_PROFILE_value(server_profiles, i); 330 331 for (j = 0; j < sk_SRTP_PROTECTION_PROFILE_num(client_profiles); j++) { 332 cprof = sk_SRTP_PROTECTION_PROFILE_value(client_profiles, j); 333 334 if (cprof->id == sprof->id) { 335 s->srtp_profile = sprof; 336 ret = 1; 337 goto done; 338 } 339 } 340 } 341 342 ret = 1; 343 344 done: 345 if (client_profiles) { 346 sk_SRTP_PROTECTION_PROFILE_free(client_profiles); 347 } 348 349 return ret; 350 } 351 352 int ssl_add_serverhello_use_srtp_ext(SSL *s, unsigned char *p, int *len, 353 int maxlen) { 354 if (p) { 355 if (maxlen < 5) { 356 OPENSSL_PUT_ERROR(SSL, ssl_add_serverhello_use_srtp_ext, 357 SSL_R_SRTP_PROTECTION_PROFILE_LIST_TOO_LONG); 358 return 0; 359 } 360 361 if (s->srtp_profile == 0) { 362 OPENSSL_PUT_ERROR(SSL, ssl_add_serverhello_use_srtp_ext, 363 SSL_R_USE_SRTP_NOT_NEGOTIATED); 364 return 0; 365 } 366 367 s2n(2, p); 368 s2n(s->srtp_profile->id, p); 369 *p++ = 0; 370 } 371 372 *len = 5; 373 374 return 1; 375 } 376 377 int ssl_parse_serverhello_use_srtp_ext(SSL *s, CBS *cbs, int *out_alert) { 378 CBS profile_ids, srtp_mki; 379 uint16_t profile_id; 380 size_t i; 381 382 STACK_OF(SRTP_PROTECTION_PROFILE) *client_profiles; 383 const SRTP_PROTECTION_PROFILE *prof; 384 385 /* The extension consists of a u16-prefixed profile ID list containing a 386 * single uint16_t profile ID, then followed by a u8-prefixed srtp_mki field. 387 * 388 * See https://tools.ietf.org/html/rfc5764#section-4.1.1 */ 389 if (!CBS_get_u16_length_prefixed(cbs, &profile_ids) || 390 !CBS_get_u16(&profile_ids, &profile_id) || CBS_len(&profile_ids) != 0 || 391 !CBS_get_u8_length_prefixed(cbs, &srtp_mki) || CBS_len(cbs) != 0) { 392 OPENSSL_PUT_ERROR(SSL, ssl_parse_serverhello_use_srtp_ext, 393 SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST); 394 *out_alert = SSL_AD_DECODE_ERROR; 395 return 0; 396 } 397 398 if (CBS_len(&srtp_mki) != 0) { 399 /* Must be no MKI, since we never offer one. */ 400 OPENSSL_PUT_ERROR(SSL, ssl_parse_serverhello_use_srtp_ext, 401 SSL_R_BAD_SRTP_MKI_VALUE); 402 *out_alert = SSL_AD_ILLEGAL_PARAMETER; 403 return 0; 404 } 405 406 client_profiles = SSL_get_srtp_profiles(s); 407 408 /* Throw an error if the server gave us an unsolicited extension */ 409 if (client_profiles == NULL) { 410 OPENSSL_PUT_ERROR(SSL, ssl_parse_serverhello_use_srtp_ext, 411 SSL_R_NO_SRTP_PROFILES); 412 *out_alert = SSL_AD_DECODE_ERROR; 413 return 0; 414 } 415 416 /* Check to see if the server gave us something we support 417 (and presumably offered). */ 418 for (i = 0; i < sk_SRTP_PROTECTION_PROFILE_num(client_profiles); i++) { 419 prof = sk_SRTP_PROTECTION_PROFILE_value(client_profiles, i); 420 421 if (prof->id == profile_id) { 422 s->srtp_profile = prof; 423 *out_alert = 0; 424 return 1; 425 } 426 } 427 428 OPENSSL_PUT_ERROR(SSL, ssl_parse_serverhello_use_srtp_ext, 429 SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST); 430 *out_alert = SSL_AD_ILLEGAL_PARAMETER; 431 return 0; 432 } 433
