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| 1 /* | |
| 2 * xfm.c | |
| 3 * | |
| 4 * Crypto transform implementation | |
| 5 * | |
| 6 * David A. McGrew | |
| 7 * Cisco Systems, Inc. | |
| 8 */ | |
| 9 /* | |
| 10 * | |
| 11 * Copyright (c) 2001-2006, Cisco Systems, Inc. | |
| 12 * All rights reserved. | |
| 13 * | |
| 14 * Redistribution and use in source and binary forms, with or without | |
| 15 * modification, are permitted provided that the following conditions | |
| 16 * are met: | |
| 17 * | |
| 18 * Redistributions of source code must retain the above copyright | |
| 19 * notice, this list of conditions and the following disclaimer. | |
| 20 * | |
| 21 * Redistributions in binary form must reproduce the above | |
| 22 * copyright notice, this list of conditions and the following | |
| 23 * disclaimer in the documentation and/or other materials provided | |
| 24 * with the distribution. | |
| 25 * | |
| 26 * Neither the name of the Cisco Systems, Inc. nor the names of its | |
| 27 * contributors may be used to endorse or promote products derived | |
| 28 * from this software without specific prior written permission. | |
| 29 * | |
| 30 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS | |
| 31 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | |
| 32 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS | |
| 33 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE | |
| 34 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, | |
| 35 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES | |
| 36 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR | |
| 37 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
| 38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, | |
| 39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | |
| 40 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED | |
| 41 * OF THE POSSIBILITY OF SUCH DAMAGE. | |
| 42 * | |
| 43 */ | |
| 44 | |
| 45 #include "cryptoalg.h" | |
| 46 #include "aes_cbc.h" | |
| 47 #include "hmac.h" | |
| 48 #include "crypto_kernel.h" /* for crypto_get_random() */ | |
| 49 | |
| 50 #define KEY_LEN 16 | |
| 51 #define ENC_KEY_LEN 16 | |
| 52 #define MAC_KEY_LEN 16 | |
| 53 #define IV_LEN 16 | |
| 54 #define TAG_LEN 12 | |
| 55 #define MAX_EXPAND 27 | |
| 56 | |
| 57 err_status_t | |
| 58 aes_128_cbc_hmac_sha1_96_func(void *key, | |
| 59 void *clear, | |
| 60 unsigned clear_len, | |
| 61 void *iv, | |
| 62 void *opaque, | |
| 63 unsigned *opaque_len, | |
| 64 void *auth_tag) { | |
| 65 aes_cbc_ctx_t aes_ctx; | |
| 66 hmac_ctx_t hmac_ctx; | |
| 67 unsigned char enc_key[ENC_KEY_LEN]; | |
| 68 unsigned char mac_key[MAC_KEY_LEN]; | |
| 69 err_status_t status; | |
| 70 | |
| 71 /* check if we're doing authentication only */ | |
| 72 if ((iv == NULL) && (opaque == NULL) && (opaque_len == NULL)) { | |
| 73 | |
| 74 /* perform authentication only */ | |
| 75 | |
| 76 } else if ((iv == NULL) || (opaque == NULL) || (opaque_len == NULL)) { | |
| 77 | |
| 78 /* | |
| 79 * bad parameter - we expect either all three pointers to be NULL, | |
| 80 * or none of those pointers to be NULL | |
| 81 */ | |
| 82 return err_status_fail; | |
| 83 | |
| 84 } else { | |
| 85 | |
| 86 /* derive encryption and authentication keys from the input key */ | |
| 87 status = hmac_init(&hmac_ctx, key, KEY_LEN); | |
| 88 if (status) return status; | |
| 89 status = hmac_compute(&hmac_ctx, "ENC", 3, ENC_KEY_LEN, enc_key); | |
| 90 if (status) return status; | |
| 91 | |
| 92 status = hmac_init(&hmac_ctx, key, KEY_LEN); | |
| 93 if (status) return status; | |
| 94 status = hmac_compute(&hmac_ctx, "MAC", 3, MAC_KEY_LEN, mac_key); | |
| 95 if (status) return status; | |
| 96 | |
| 97 | |
| 98 /* perform encryption and authentication */ | |
| 99 | |
| 100 /* set aes key */ | |
| 101 status = aes_cbc_context_init(&aes_ctx, key, ENC_KEY_LEN, direction_encrypt)
; | |
| 102 if (status) return status; | |
| 103 | |
| 104 /* set iv */ | |
| 105 status = crypto_get_random(iv, IV_LEN); | |
| 106 if (status) return status; | |
| 107 status = aes_cbc_set_iv(&aes_ctx, iv); | |
| 108 | |
| 109 /* encrypt the opaque data */ | |
| 110 status = aes_cbc_nist_encrypt(&aes_ctx, opaque, opaque_len); | |
| 111 if (status) return status; | |
| 112 | |
| 113 /* authenticate clear and opaque data */ | |
| 114 status = hmac_init(&hmac_ctx, mac_key, MAC_KEY_LEN); | |
| 115 if (status) return status; | |
| 116 | |
| 117 status = hmac_start(&hmac_ctx); | |
| 118 if (status) return status; | |
| 119 | |
| 120 status = hmac_update(&hmac_ctx, clear, clear_len); | |
| 121 if (status) return status; | |
| 122 | |
| 123 status = hmac_compute(&hmac_ctx, opaque, *opaque_len, TAG_LEN, auth_tag); | |
| 124 if (status) return status; | |
| 125 | |
| 126 } | |
| 127 | |
| 128 return err_status_ok; | |
| 129 } | |
| 130 | |
| 131 err_status_t | |
| 132 aes_128_cbc_hmac_sha1_96_inv(void *key, | |
| 133 void *clear, | |
| 134 unsigned clear_len, | |
| 135 void *iv, | |
| 136 void *opaque, | |
| 137 unsigned *opaque_len, | |
| 138 void *auth_tag) { | |
| 139 aes_cbc_ctx_t aes_ctx; | |
| 140 hmac_ctx_t hmac_ctx; | |
| 141 unsigned char enc_key[ENC_KEY_LEN]; | |
| 142 unsigned char mac_key[MAC_KEY_LEN]; | |
| 143 unsigned char tmp_tag[TAG_LEN]; | |
| 144 unsigned char *tag = auth_tag; | |
| 145 err_status_t status; | |
| 146 int i; | |
| 147 | |
| 148 /* check if we're doing authentication only */ | |
| 149 if ((iv == NULL) && (opaque == NULL) && (opaque_len == NULL)) { | |
| 150 | |
| 151 /* perform authentication only */ | |
| 152 | |
| 153 } else if ((iv == NULL) || (opaque == NULL) || (opaque_len == NULL)) { | |
| 154 | |
| 155 /* | |
| 156 * bad parameter - we expect either all three pointers to be NULL, | |
| 157 * or none of those pointers to be NULL | |
| 158 */ | |
| 159 return err_status_fail; | |
| 160 | |
| 161 } else { | |
| 162 | |
| 163 /* derive encryption and authentication keys from the input key */ | |
| 164 status = hmac_init(&hmac_ctx, key, KEY_LEN); | |
| 165 if (status) return status; | |
| 166 status = hmac_compute(&hmac_ctx, "ENC", 3, ENC_KEY_LEN, enc_key); | |
| 167 if (status) return status; | |
| 168 | |
| 169 status = hmac_init(&hmac_ctx, key, KEY_LEN); | |
| 170 if (status) return status; | |
| 171 status = hmac_compute(&hmac_ctx, "MAC", 3, MAC_KEY_LEN, mac_key); | |
| 172 if (status) return status; | |
| 173 | |
| 174 /* perform encryption and authentication */ | |
| 175 | |
| 176 /* set aes key */ | |
| 177 status = aes_cbc_context_init(&aes_ctx, key, ENC_KEY_LEN, direction_decrypt)
; | |
| 178 if (status) return status; | |
| 179 | |
| 180 /* set iv */ | |
| 181 status = rand_source_get_octet_string(iv, IV_LEN); | |
| 182 if (status) return status; | |
| 183 status = aes_cbc_set_iv(&aes_ctx, iv); | |
| 184 | |
| 185 /* encrypt the opaque data */ | |
| 186 status = aes_cbc_nist_decrypt(&aes_ctx, opaque, opaque_len); | |
| 187 if (status) return status; | |
| 188 | |
| 189 /* authenticate clear and opaque data */ | |
| 190 status = hmac_init(&hmac_ctx, mac_key, MAC_KEY_LEN); | |
| 191 if (status) return status; | |
| 192 | |
| 193 status = hmac_start(&hmac_ctx); | |
| 194 if (status) return status; | |
| 195 | |
| 196 status = hmac_update(&hmac_ctx, clear, clear_len); | |
| 197 if (status) return status; | |
| 198 | |
| 199 status = hmac_compute(&hmac_ctx, opaque, *opaque_len, TAG_LEN, tmp_tag); | |
| 200 if (status) return status; | |
| 201 | |
| 202 /* compare the computed tag with the one provided as input */ | |
| 203 for (i=0; i < TAG_LEN; i++) | |
| 204 if (tmp_tag[i] != tag[i]) | |
| 205 return err_status_auth_fail; | |
| 206 | |
| 207 } | |
| 208 | |
| 209 return err_status_ok; | |
| 210 } | |
| 211 | |
| 212 | |
| 213 #define ENC 1 | |
| 214 | |
| 215 #define DEBUG 0 | |
| 216 | |
| 217 err_status_t | |
| 218 aes_128_cbc_hmac_sha1_96_enc(void *key, | |
| 219 const void *clear, | |
| 220 unsigned clear_len, | |
| 221 void *iv, | |
| 222 void *opaque, | |
| 223 unsigned *opaque_len) { | |
| 224 aes_cbc_ctx_t aes_ctx; | |
| 225 hmac_ctx_t hmac_ctx; | |
| 226 unsigned char enc_key[ENC_KEY_LEN]; | |
| 227 unsigned char mac_key[MAC_KEY_LEN]; | |
| 228 unsigned char *auth_tag; | |
| 229 err_status_t status; | |
| 230 | |
| 231 /* check if we're doing authentication only */ | |
| 232 if ((iv == NULL) && (opaque == NULL) && (opaque_len == NULL)) { | |
| 233 | |
| 234 /* perform authentication only */ | |
| 235 | |
| 236 } else if ((iv == NULL) || (opaque == NULL) || (opaque_len == NULL)) { | |
| 237 | |
| 238 /* | |
| 239 * bad parameter - we expect either all three pointers to be NULL, | |
| 240 * or none of those pointers to be NULL | |
| 241 */ | |
| 242 return err_status_fail; | |
| 243 | |
| 244 } else { | |
| 245 | |
| 246 #if DEBUG | |
| 247 printf("ENC using key %s\n", octet_string_hex_string(key, KEY_LEN)); | |
| 248 #endif | |
| 249 | |
| 250 /* derive encryption and authentication keys from the input key */ | |
| 251 status = hmac_init(&hmac_ctx, key, KEY_LEN); | |
| 252 if (status) return status; | |
| 253 status = hmac_compute(&hmac_ctx, "ENC", 3, ENC_KEY_LEN, enc_key); | |
| 254 if (status) return status; | |
| 255 | |
| 256 status = hmac_init(&hmac_ctx, key, KEY_LEN); | |
| 257 if (status) return status; | |
| 258 status = hmac_compute(&hmac_ctx, "MAC", 3, MAC_KEY_LEN, mac_key); | |
| 259 if (status) return status; | |
| 260 | |
| 261 | |
| 262 /* perform encryption and authentication */ | |
| 263 | |
| 264 /* set aes key */ | |
| 265 status = aes_cbc_context_init(&aes_ctx, key, ENC_KEY_LEN, direction_encrypt)
; | |
| 266 if (status) return status; | |
| 267 | |
| 268 /* set iv */ | |
| 269 status = rand_source_get_octet_string(iv, IV_LEN); | |
| 270 if (status) return status; | |
| 271 status = aes_cbc_set_iv(&aes_ctx, iv); | |
| 272 if (status) return status; | |
| 273 | |
| 274 #if DEBUG | |
| 275 printf("plaintext len: %d\n", *opaque_len); | |
| 276 printf("iv: %s\n", octet_string_hex_string(iv, IV_LEN)); | |
| 277 printf("plaintext: %s\n", octet_string_hex_string(opaque, *opaque_len)); | |
| 278 #endif | |
| 279 | |
| 280 #if ENC | |
| 281 /* encrypt the opaque data */ | |
| 282 status = aes_cbc_nist_encrypt(&aes_ctx, opaque, opaque_len); | |
| 283 if (status) return status; | |
| 284 #endif | |
| 285 | |
| 286 #if DEBUG | |
| 287 printf("ciphertext len: %d\n", *opaque_len); | |
| 288 printf("ciphertext: %s\n", octet_string_hex_string(opaque, *opaque_len)); | |
| 289 #endif | |
| 290 | |
| 291 /* | |
| 292 * authenticate clear and opaque data, then write the | |
| 293 * authentication tag to the location immediately following the | |
| 294 * ciphertext | |
| 295 */ | |
| 296 status = hmac_init(&hmac_ctx, mac_key, MAC_KEY_LEN); | |
| 297 if (status) return status; | |
| 298 | |
| 299 status = hmac_start(&hmac_ctx); | |
| 300 if (status) return status; | |
| 301 | |
| 302 status = hmac_update(&hmac_ctx, clear, clear_len); | |
| 303 if (status) return status; | |
| 304 #if DEBUG | |
| 305 printf("hmac input: %s\n", | |
| 306 octet_string_hex_string(clear, clear_len)); | |
| 307 #endif | |
| 308 auth_tag = (unsigned char *)opaque; | |
| 309 auth_tag += *opaque_len; | |
| 310 status = hmac_compute(&hmac_ctx, opaque, *opaque_len, TAG_LEN, auth_tag); | |
| 311 if (status) return status; | |
| 312 #if DEBUG | |
| 313 printf("hmac input: %s\n", | |
| 314 octet_string_hex_string(opaque, *opaque_len)); | |
| 315 #endif | |
| 316 /* bump up the opaque_len to reflect the authentication tag */ | |
| 317 *opaque_len += TAG_LEN; | |
| 318 | |
| 319 #if DEBUG | |
| 320 printf("prot data len: %d\n", *opaque_len); | |
| 321 printf("prot data: %s\n", octet_string_hex_string(opaque, *opaque_len)); | |
| 322 #endif | |
| 323 } | |
| 324 | |
| 325 return err_status_ok; | |
| 326 } | |
| 327 | |
| 328 err_status_t | |
| 329 aes_128_cbc_hmac_sha1_96_dec(void *key, | |
| 330 const void *clear, | |
| 331 unsigned clear_len, | |
| 332 void *iv, | |
| 333 void *opaque, | |
| 334 unsigned *opaque_len) { | |
| 335 aes_cbc_ctx_t aes_ctx; | |
| 336 hmac_ctx_t hmac_ctx; | |
| 337 unsigned char enc_key[ENC_KEY_LEN]; | |
| 338 unsigned char mac_key[MAC_KEY_LEN]; | |
| 339 unsigned char tmp_tag[TAG_LEN]; | |
| 340 unsigned char *auth_tag; | |
| 341 unsigned ciphertext_len; | |
| 342 err_status_t status; | |
| 343 int i; | |
| 344 | |
| 345 /* check if we're doing authentication only */ | |
| 346 if ((iv == NULL) && (opaque == NULL) && (opaque_len == NULL)) { | |
| 347 | |
| 348 /* perform authentication only */ | |
| 349 | |
| 350 } else if ((iv == NULL) || (opaque == NULL) || (opaque_len == NULL)) { | |
| 351 | |
| 352 /* | |
| 353 * bad parameter - we expect either all three pointers to be NULL, | |
| 354 * or none of those pointers to be NULL | |
| 355 */ | |
| 356 return err_status_fail; | |
| 357 | |
| 358 } else { | |
| 359 #if DEBUG | |
| 360 printf("DEC using key %s\n", octet_string_hex_string(key, KEY_LEN)); | |
| 361 #endif | |
| 362 | |
| 363 /* derive encryption and authentication keys from the input key */ | |
| 364 status = hmac_init(&hmac_ctx, key, KEY_LEN); | |
| 365 if (status) return status; | |
| 366 status = hmac_compute(&hmac_ctx, "ENC", 3, ENC_KEY_LEN, enc_key); | |
| 367 if (status) return status; | |
| 368 | |
| 369 status = hmac_init(&hmac_ctx, key, KEY_LEN); | |
| 370 if (status) return status; | |
| 371 status = hmac_compute(&hmac_ctx, "MAC", 3, MAC_KEY_LEN, mac_key); | |
| 372 if (status) return status; | |
| 373 | |
| 374 #if DEBUG | |
| 375 printf("prot data len: %d\n", *opaque_len); | |
| 376 printf("prot data: %s\n", octet_string_hex_string(opaque, *opaque_len)); | |
| 377 #endif | |
| 378 | |
| 379 /* | |
| 380 * set the protected data length to that of the ciphertext, by | |
| 381 * subtracting out the length of the authentication tag | |
| 382 */ | |
| 383 ciphertext_len = *opaque_len - TAG_LEN; | |
| 384 | |
| 385 #if DEBUG | |
| 386 printf("ciphertext len: %d\n", ciphertext_len); | |
| 387 #endif | |
| 388 /* verify the authentication tag */ | |
| 389 | |
| 390 /* | |
| 391 * compute the authentication tag for the clear and opaque data, | |
| 392 * and write it to a temporary location | |
| 393 */ | |
| 394 status = hmac_init(&hmac_ctx, mac_key, MAC_KEY_LEN); | |
| 395 if (status) return status; | |
| 396 | |
| 397 status = hmac_start(&hmac_ctx); | |
| 398 if (status) return status; | |
| 399 | |
| 400 status = hmac_update(&hmac_ctx, clear, clear_len); | |
| 401 if (status) return status; | |
| 402 | |
| 403 #if DEBUG | |
| 404 printf("hmac input: %s\n", | |
| 405 octet_string_hex_string(clear, clear_len)); | |
| 406 #endif | |
| 407 | |
| 408 status = hmac_compute(&hmac_ctx, opaque, ciphertext_len, TAG_LEN, tmp_tag); | |
| 409 if (status) return status; | |
| 410 | |
| 411 #if DEBUG | |
| 412 printf("hmac input: %s\n", | |
| 413 octet_string_hex_string(opaque, ciphertext_len)); | |
| 414 #endif | |
| 415 | |
| 416 /* | |
| 417 * compare the computed tag with the one provided as input (which | |
| 418 * immediately follows the ciphertext) | |
| 419 */ | |
| 420 auth_tag = (unsigned char *)opaque; | |
| 421 auth_tag += ciphertext_len; | |
| 422 #if DEBUG | |
| 423 printf("auth_tag: %s\n", octet_string_hex_string(auth_tag, TAG_LEN)); | |
| 424 printf("tmp_tag: %s\n", octet_string_hex_string(tmp_tag, TAG_LEN)); | |
| 425 #endif | |
| 426 for (i=0; i < TAG_LEN; i++) { | |
| 427 if (tmp_tag[i] != auth_tag[i]) | |
| 428 return err_status_auth_fail; | |
| 429 } | |
| 430 | |
| 431 /* bump down the opaque_len to reflect the authentication tag */ | |
| 432 *opaque_len -= TAG_LEN; | |
| 433 | |
| 434 /* decrypt the confidential data */ | |
| 435 status = aes_cbc_context_init(&aes_ctx, key, ENC_KEY_LEN, direction_decrypt)
; | |
| 436 if (status) return status; | |
| 437 status = aes_cbc_set_iv(&aes_ctx, iv); | |
| 438 if (status) return status; | |
| 439 | |
| 440 #if DEBUG | |
| 441 printf("ciphertext: %s\n", octet_string_hex_string(opaque, *opaque_len)); | |
| 442 printf("iv: %s\n", octet_string_hex_string(iv, IV_LEN)); | |
| 443 #endif | |
| 444 | |
| 445 #if ENC | |
| 446 status = aes_cbc_nist_decrypt(&aes_ctx, opaque, &ciphertext_len); | |
| 447 if (status) return status; | |
| 448 #endif | |
| 449 | |
| 450 #if DEBUG | |
| 451 printf("plaintext len: %d\n", ciphertext_len); | |
| 452 printf("plaintext: %s\n", | |
| 453 octet_string_hex_string(opaque, ciphertext_len)); | |
| 454 #endif | |
| 455 | |
| 456 /* indicate the length of the plaintext */ | |
| 457 *opaque_len = ciphertext_len; | |
| 458 } | |
| 459 | |
| 460 return err_status_ok; | |
| 461 } | |
| 462 | |
| 463 cryptoalg_ctx_t cryptoalg_ctx = { | |
| 464 aes_128_cbc_hmac_sha1_96_enc, | |
| 465 aes_128_cbc_hmac_sha1_96_dec, | |
| 466 KEY_LEN, | |
| 467 IV_LEN, | |
| 468 TAG_LEN, | |
| 469 MAX_EXPAND, | |
| 470 }; | |
| 471 | |
| 472 cryptoalg_t cryptoalg = &cryptoalg_ctx; | |
| 473 | |
| 474 #define NULL_TAG_LEN 12 | |
| 475 | |
| 476 err_status_t | |
| 477 null_enc(void *key, | |
| 478 const void *clear, | |
| 479 unsigned clear_len, | |
| 480 void *iv, | |
| 481 void *opaque, | |
| 482 unsigned *opaque_len) { | |
| 483 int i; | |
| 484 unsigned char *auth_tag; | |
| 485 unsigned char *init_vec = iv; | |
| 486 | |
| 487 /* check if we're doing authentication only */ | |
| 488 if ((iv == NULL) && (opaque == NULL) && (opaque_len == NULL)) { | |
| 489 | |
| 490 /* perform authentication only */ | |
| 491 | |
| 492 } else if ((iv == NULL) || (opaque == NULL) || (opaque_len == NULL)) { | |
| 493 | |
| 494 /* | |
| 495 * bad parameter - we expect either all three pointers to be NULL, | |
| 496 * or none of those pointers to be NULL | |
| 497 */ | |
| 498 return err_status_fail; | |
| 499 | |
| 500 } else { | |
| 501 | |
| 502 #if DEBUG | |
| 503 printf("NULL ENC using key %s\n", octet_string_hex_string(key, KEY_LEN)); | |
| 504 printf("NULL_TAG_LEN: %d\n", NULL_TAG_LEN); | |
| 505 printf("plaintext len: %d\n", *opaque_len); | |
| 506 #endif | |
| 507 for (i=0; i < IV_LEN; i++) | |
| 508 init_vec[i] = i + (i * 16); | |
| 509 #if DEBUG | |
| 510 printf("iv: %s\n", | |
| 511 octet_string_hex_string(iv, IV_LEN)); | |
| 512 printf("plaintext: %s\n", | |
| 513 octet_string_hex_string(opaque, *opaque_len)); | |
| 514 #endif | |
| 515 auth_tag = opaque; | |
| 516 auth_tag += *opaque_len; | |
| 517 for (i=0; i < NULL_TAG_LEN; i++) | |
| 518 auth_tag[i] = i + (i * 16); | |
| 519 *opaque_len += NULL_TAG_LEN; | |
| 520 #if DEBUG | |
| 521 printf("protected data len: %d\n", *opaque_len); | |
| 522 printf("protected data: %s\n", | |
| 523 octet_string_hex_string(opaque, *opaque_len)); | |
| 524 #endif | |
| 525 | |
| 526 } | |
| 527 | |
| 528 return err_status_ok; | |
| 529 } | |
| 530 | |
| 531 err_status_t | |
| 532 null_dec(void *key, | |
| 533 const void *clear, | |
| 534 unsigned clear_len, | |
| 535 void *iv, | |
| 536 void *opaque, | |
| 537 unsigned *opaque_len) { | |
| 538 unsigned char *auth_tag; | |
| 539 | |
| 540 /* check if we're doing authentication only */ | |
| 541 if ((iv == NULL) && (opaque == NULL) && (opaque_len == NULL)) { | |
| 542 | |
| 543 /* perform authentication only */ | |
| 544 | |
| 545 } else if ((iv == NULL) || (opaque == NULL) || (opaque_len == NULL)) { | |
| 546 | |
| 547 /* | |
| 548 * bad parameter - we expect either all three pointers to be NULL, | |
| 549 * or none of those pointers to be NULL | |
| 550 */ | |
| 551 return err_status_fail; | |
| 552 | |
| 553 } else { | |
| 554 | |
| 555 #if DEBUG | |
| 556 printf("NULL DEC using key %s\n", octet_string_hex_string(key, KEY_LEN)); | |
| 557 | |
| 558 printf("protected data len: %d\n", *opaque_len); | |
| 559 printf("protected data: %s\n", | |
| 560 octet_string_hex_string(opaque, *opaque_len)); | |
| 561 #endif | |
| 562 auth_tag = opaque; | |
| 563 auth_tag += (*opaque_len - NULL_TAG_LEN); | |
| 564 #if DEBUG | |
| 565 printf("iv: %s\n", octet_string_hex_string(iv, IV_LEN)); | |
| 566 #endif | |
| 567 *opaque_len -= NULL_TAG_LEN; | |
| 568 #if DEBUG | |
| 569 printf("plaintext len: %d\n", *opaque_len); | |
| 570 printf("plaintext: %s\n", | |
| 571 octet_string_hex_string(opaque, *opaque_len)); | |
| 572 #endif | |
| 573 } | |
| 574 | |
| 575 return err_status_ok; | |
| 576 } | |
| 577 | |
| 578 cryptoalg_ctx_t null_cryptoalg_ctx = { | |
| 579 null_enc, | |
| 580 null_dec, | |
| 581 KEY_LEN, | |
| 582 IV_LEN, | |
| 583 NULL_TAG_LEN, | |
| 584 MAX_EXPAND, | |
| 585 }; | |
| 586 | |
| 587 cryptoalg_t null_cryptoalg = &null_cryptoalg_ctx; | |
| 588 | |
| 589 int | |
| 590 cryptoalg_get_id(cryptoalg_t c) { | |
| 591 if (c == cryptoalg) | |
| 592 return 1; | |
| 593 return 0; | |
| 594 } | |
| 595 | |
| 596 cryptoalg_t | |
| 597 cryptoalg_find_by_id(int id) { | |
| 598 switch(id) { | |
| 599 case 1: | |
| 600 return cryptoalg; | |
| 601 default: | |
| 602 break; | |
| 603 } | |
| 604 return 0; | |
| 605 } | |
| OLD | NEW |
|---|
Chromium Code Reviews
Issue 889083003:
Update libsrtp to upstream 1.5.0 (Closed)
Base URL: https://chromium.googlesource.com/chromium/deps/libsrtp@master