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 #include <openssl/cipher.h> 58 59 #include <assert.h> 60 #include <string.h> 61 62 #include <openssl/err.h> 63 #include <openssl/mem.h> 64 #include <openssl/nid.h> 65 66 #include "internal.h" 67 #include "../../internal.h" 68 69 70 void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *ctx) { 71 OPENSSL_memset(ctx, 0, sizeof(EVP_CIPHER_CTX)); 72 } 73 74 EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void) { 75 EVP_CIPHER_CTX *ctx = OPENSSL_malloc(sizeof(EVP_CIPHER_CTX)); 76 if (ctx) { 77 EVP_CIPHER_CTX_init(ctx); 78 } 79 return ctx; 80 } 81 82 int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *c) { 83 if (c->cipher != NULL) { 84 if (c->cipher->cleanup) { 85 c->cipher->cleanup(c); 86 } 87 OPENSSL_cleanse(c->cipher_data, c->cipher->ctx_size); 88 } 89 OPENSSL_free(c->cipher_data); 90 91 OPENSSL_memset(c, 0, sizeof(EVP_CIPHER_CTX)); 92 return 1; 93 } 94 95 void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx) { 96 if (ctx) { 97 EVP_CIPHER_CTX_cleanup(ctx); 98 OPENSSL_free(ctx); 99 } 100 } 101 102 int EVP_CIPHER_CTX_copy(EVP_CIPHER_CTX *out, const EVP_CIPHER_CTX *in) { 103 if (in == NULL || in->cipher == NULL) { 104 OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_INPUT_NOT_INITIALIZED); 105 return 0; 106 } 107 108 EVP_CIPHER_CTX_cleanup(out); 109 OPENSSL_memcpy(out, in, sizeof(EVP_CIPHER_CTX)); 110 111 if (in->cipher_data && in->cipher->ctx_size) { 112 out->cipher_data = OPENSSL_malloc(in->cipher->ctx_size); 113 if (!out->cipher_data) { 114 out->cipher = NULL; 115 OPENSSL_PUT_ERROR(CIPHER, ERR_R_MALLOC_FAILURE); 116 return 0; 117 } 118 OPENSSL_memcpy(out->cipher_data, in->cipher_data, in->cipher->ctx_size); 119 } 120 121 if (in->cipher->flags & EVP_CIPH_CUSTOM_COPY) { 122 if (!in->cipher->ctrl((EVP_CIPHER_CTX *)in, EVP_CTRL_COPY, 0, out)) { 123 out->cipher = NULL; 124 return 0; 125 } 126 } 127 128 return 1; 129 } 130 131 int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, 132 ENGINE *engine, const uint8_t *key, const uint8_t *iv, 133 int enc) { 134 if (enc == -1) { 135 enc = ctx->encrypt; 136 } else { 137 if (enc) { 138 enc = 1; 139 } 140 ctx->encrypt = enc; 141 } 142 143 if (cipher) { 144 /* Ensure a context left from last time is cleared (the previous check 145 * attempted to avoid this if the same ENGINE and EVP_CIPHER could be 146 * used). */ 147 if (ctx->cipher) { 148 EVP_CIPHER_CTX_cleanup(ctx); 149 /* Restore encrypt and flags */ 150 ctx->encrypt = enc; 151 } 152 153 ctx->cipher = cipher; 154 if (ctx->cipher->ctx_size) { 155 ctx->cipher_data = OPENSSL_malloc(ctx->cipher->ctx_size); 156 if (!ctx->cipher_data) { 157 ctx->cipher = NULL; 158 OPENSSL_PUT_ERROR(CIPHER, ERR_R_MALLOC_FAILURE); 159 return 0; 160 } 161 } else { 162 ctx->cipher_data = NULL; 163 } 164 165 ctx->key_len = cipher->key_len; 166 ctx->flags = 0; 167 168 if (ctx->cipher->flags & EVP_CIPH_CTRL_INIT) { 169 if (!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_INIT, 0, NULL)) { 170 ctx->cipher = NULL; 171 OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_INITIALIZATION_ERROR); 172 return 0; 173 } 174 } 175 } else if (!ctx->cipher) { 176 OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_NO_CIPHER_SET); 177 return 0; 178 } 179 180 /* we assume block size is a power of 2 in *cryptUpdate */ 181 assert(ctx->cipher->block_size == 1 || ctx->cipher->block_size == 8 || 182 ctx->cipher->block_size == 16); 183 184 if (!(EVP_CIPHER_CTX_flags(ctx) & EVP_CIPH_CUSTOM_IV)) { 185 switch (EVP_CIPHER_CTX_mode(ctx)) { 186 case EVP_CIPH_STREAM_CIPHER: 187 case EVP_CIPH_ECB_MODE: 188 break; 189 190 case EVP_CIPH_CFB_MODE: 191 ctx->num = 0; 192 /* fall-through */ 193 194 case EVP_CIPH_CBC_MODE: 195 assert(EVP_CIPHER_CTX_iv_length(ctx) <= sizeof(ctx->iv)); 196 if (iv) { 197 OPENSSL_memcpy(ctx->oiv, iv, EVP_CIPHER_CTX_iv_length(ctx)); 198 } 199 OPENSSL_memcpy(ctx->iv, ctx->oiv, EVP_CIPHER_CTX_iv_length(ctx)); 200 break; 201 202 case EVP_CIPH_CTR_MODE: 203 case EVP_CIPH_OFB_MODE: 204 ctx->num = 0; 205 /* Don't reuse IV for CTR mode */ 206 if (iv) { 207 OPENSSL_memcpy(ctx->iv, iv, EVP_CIPHER_CTX_iv_length(ctx)); 208 } 209 break; 210 211 default: 212 return 0; 213 } 214 } 215 216 if (key || (ctx->cipher->flags & EVP_CIPH_ALWAYS_CALL_INIT)) { 217 if (!ctx->cipher->init(ctx, key, iv, enc)) { 218 return 0; 219 } 220 } 221 222 ctx->buf_len = 0; 223 ctx->final_used = 0; 224 ctx->block_mask = ctx->cipher->block_size - 1; 225 return 1; 226 } 227 228 int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, 229 ENGINE *impl, const uint8_t *key, const uint8_t *iv) { 230 return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 1); 231 } 232 233 int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, 234 ENGINE *impl, const uint8_t *key, const uint8_t *iv) { 235 return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 0); 236 } 237 238 int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, uint8_t *out, int *out_len, 239 const uint8_t *in, int in_len) { 240 int i, j, bl; 241 242 if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) { 243 i = ctx->cipher->cipher(ctx, out, in, in_len); 244 if (i < 0) { 245 return 0; 246 } else { 247 *out_len = i; 248 } 249 return 1; 250 } 251 252 if (in_len <= 0) { 253 *out_len = 0; 254 return in_len == 0; 255 } 256 257 if (ctx->buf_len == 0 && (in_len & ctx->block_mask) == 0) { 258 if (ctx->cipher->cipher(ctx, out, in, in_len)) { 259 *out_len = in_len; 260 return 1; 261 } else { 262 *out_len = 0; 263 return 0; 264 } 265 } 266 267 i = ctx->buf_len; 268 bl = ctx->cipher->block_size; 269 assert(bl <= (int)sizeof(ctx->buf)); 270 if (i != 0) { 271 if (bl - i > in_len) { 272 OPENSSL_memcpy(&ctx->buf[i], in, in_len); 273 ctx->buf_len += in_len; 274 *out_len = 0; 275 return 1; 276 } else { 277 j = bl - i; 278 OPENSSL_memcpy(&ctx->buf[i], in, j); 279 if (!ctx->cipher->cipher(ctx, out, ctx->buf, bl)) { 280 return 0; 281 } 282 in_len -= j; 283 in += j; 284 out += bl; 285 *out_len = bl; 286 } 287 } else { 288 *out_len = 0; 289 } 290 291 i = in_len & ctx->block_mask; 292 in_len -= i; 293 if (in_len > 0) { 294 if (!ctx->cipher->cipher(ctx, out, in, in_len)) { 295 return 0; 296 } 297 *out_len += in_len; 298 } 299 300 if (i != 0) { 301 OPENSSL_memcpy(ctx->buf, &in[in_len], i); 302 } 303 ctx->buf_len = i; 304 return 1; 305 } 306 307 int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, uint8_t *out, int *out_len) { 308 int n, ret; 309 unsigned int i, b, bl; 310 311 if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) { 312 ret = ctx->cipher->cipher(ctx, out, NULL, 0); 313 if (ret < 0) { 314 return 0; 315 } else { 316 *out_len = ret; 317 } 318 return 1; 319 } 320 321 b = ctx->cipher->block_size; 322 assert(b <= sizeof(ctx->buf)); 323 if (b == 1) { 324 *out_len = 0; 325 return 1; 326 } 327 328 bl = ctx->buf_len; 329 if (ctx->flags & EVP_CIPH_NO_PADDING) { 330 if (bl) { 331 OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH); 332 return 0; 333 } 334 *out_len = 0; 335 return 1; 336 } 337 338 n = b - bl; 339 for (i = bl; i < b; i++) { 340 ctx->buf[i] = n; 341 } 342 ret = ctx->cipher->cipher(ctx, out, ctx->buf, b); 343 344 if (ret) { 345 *out_len = b; 346 } 347 348 return ret; 349 } 350 351 int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, uint8_t *out, int *out_len, 352 const uint8_t *in, int in_len) { 353 int fix_len; 354 unsigned int b; 355 356 if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) { 357 int r = ctx->cipher->cipher(ctx, out, in, in_len); 358 if (r < 0) { 359 *out_len = 0; 360 return 0; 361 } else { 362 *out_len = r; 363 } 364 return 1; 365 } 366 367 if (in_len <= 0) { 368 *out_len = 0; 369 return in_len == 0; 370 } 371 372 if (ctx->flags & EVP_CIPH_NO_PADDING) { 373 return EVP_EncryptUpdate(ctx, out, out_len, in, in_len); 374 } 375 376 b = ctx->cipher->block_size; 377 assert(b <= sizeof(ctx->final)); 378 379 if (ctx->final_used) { 380 OPENSSL_memcpy(out, ctx->final, b); 381 out += b; 382 fix_len = 1; 383 } else { 384 fix_len = 0; 385 } 386 387 if (!EVP_EncryptUpdate(ctx, out, out_len, in, in_len)) { 388 return 0; 389 } 390 391 /* if we have 'decrypted' a multiple of block size, make sure 392 * we have a copy of this last block */ 393 if (b > 1 && !ctx->buf_len) { 394 *out_len -= b; 395 ctx->final_used = 1; 396 OPENSSL_memcpy(ctx->final, &out[*out_len], b); 397 } else { 398 ctx->final_used = 0; 399 } 400 401 if (fix_len) { 402 *out_len += b; 403 } 404 405 return 1; 406 } 407 408 int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *out_len) { 409 int i, n; 410 unsigned int b; 411 *out_len = 0; 412 413 if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) { 414 i = ctx->cipher->cipher(ctx, out, NULL, 0); 415 if (i < 0) { 416 return 0; 417 } else { 418 *out_len = i; 419 } 420 return 1; 421 } 422 423 b = ctx->cipher->block_size; 424 if (ctx->flags & EVP_CIPH_NO_PADDING) { 425 if (ctx->buf_len) { 426 OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH); 427 return 0; 428 } 429 *out_len = 0; 430 return 1; 431 } 432 433 if (b > 1) { 434 if (ctx->buf_len || !ctx->final_used) { 435 OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_WRONG_FINAL_BLOCK_LENGTH); 436 return 0; 437 } 438 assert(b <= sizeof(ctx->final)); 439 440 /* The following assumes that the ciphertext has been authenticated. 441 * Otherwise it provides a padding oracle. */ 442 n = ctx->final[b - 1]; 443 if (n == 0 || n > (int)b) { 444 OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_BAD_DECRYPT); 445 return 0; 446 } 447 448 for (i = 0; i < n; i++) { 449 if (ctx->final[--b] != n) { 450 OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_BAD_DECRYPT); 451 return 0; 452 } 453 } 454 455 n = ctx->cipher->block_size - n; 456 for (i = 0; i < n; i++) { 457 out[i] = ctx->final[i]; 458 } 459 *out_len = n; 460 } else { 461 *out_len = 0; 462 } 463 464 return 1; 465 } 466 467 int EVP_Cipher(EVP_CIPHER_CTX *ctx, uint8_t *out, const uint8_t *in, 468 size_t in_len) { 469 return ctx->cipher->cipher(ctx, out, in, in_len); 470 } 471 472 int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, uint8_t *out, int *out_len, 473 const uint8_t *in, int in_len) { 474 if (ctx->encrypt) { 475 return EVP_EncryptUpdate(ctx, out, out_len, in, in_len); 476 } else { 477 return EVP_DecryptUpdate(ctx, out, out_len, in, in_len); 478 } 479 } 480 481 int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, uint8_t *out, int *out_len) { 482 if (ctx->encrypt) { 483 return EVP_EncryptFinal_ex(ctx, out, out_len); 484 } else { 485 return EVP_DecryptFinal_ex(ctx, out, out_len); 486 } 487 } 488 489 const EVP_CIPHER *EVP_CIPHER_CTX_cipher(const EVP_CIPHER_CTX *ctx) { 490 return ctx->cipher; 491 } 492 493 int EVP_CIPHER_CTX_nid(const EVP_CIPHER_CTX *ctx) { 494 return ctx->cipher->nid; 495 } 496 497 unsigned EVP_CIPHER_CTX_block_size(const EVP_CIPHER_CTX *ctx) { 498 return ctx->cipher->block_size; 499 } 500 501 unsigned EVP_CIPHER_CTX_key_length(const EVP_CIPHER_CTX *ctx) { 502 return ctx->key_len; 503 } 504 505 unsigned EVP_CIPHER_CTX_iv_length(const EVP_CIPHER_CTX *ctx) { 506 return ctx->cipher->iv_len; 507 } 508 509 void *EVP_CIPHER_CTX_get_app_data(const EVP_CIPHER_CTX *ctx) { 510 return ctx->app_data; 511 } 512 513 void EVP_CIPHER_CTX_set_app_data(EVP_CIPHER_CTX *ctx, void *data) { 514 ctx->app_data = data; 515 } 516 517 uint32_t EVP_CIPHER_CTX_flags(const EVP_CIPHER_CTX *ctx) { 518 return ctx->cipher->flags & ~EVP_CIPH_MODE_MASK; 519 } 520 521 uint32_t EVP_CIPHER_CTX_mode(const EVP_CIPHER_CTX *ctx) { 522 return ctx->cipher->flags & EVP_CIPH_MODE_MASK; 523 } 524 525 int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int command, int arg, void *ptr) { 526 int ret; 527 if (!ctx->cipher) { 528 OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_NO_CIPHER_SET); 529 return 0; 530 } 531 532 if (!ctx->cipher->ctrl) { 533 OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_CTRL_NOT_IMPLEMENTED); 534 return 0; 535 } 536 537 ret = ctx->cipher->ctrl(ctx, command, arg, ptr); 538 if (ret == -1) { 539 OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_CTRL_OPERATION_NOT_IMPLEMENTED); 540 return 0; 541 } 542 543 return ret; 544 } 545 546 int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad) { 547 if (pad) { 548 ctx->flags &= ~EVP_CIPH_NO_PADDING; 549 } else { 550 ctx->flags |= EVP_CIPH_NO_PADDING; 551 } 552 return 1; 553 } 554 555 int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *c, unsigned key_len) { 556 if (c->key_len == key_len) { 557 return 1; 558 } 559 560 if (key_len == 0 || !(c->cipher->flags & EVP_CIPH_VARIABLE_LENGTH)) { 561 OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_INVALID_KEY_LENGTH); 562 return 0; 563 } 564 565 c->key_len = key_len; 566 return 1; 567 } 568 569 int EVP_CIPHER_nid(const EVP_CIPHER *cipher) { return cipher->nid; } 570 571 unsigned EVP_CIPHER_block_size(const EVP_CIPHER *cipher) { 572 return cipher->block_size; 573 } 574 575 unsigned EVP_CIPHER_key_length(const EVP_CIPHER *cipher) { 576 return cipher->key_len; 577 } 578 579 unsigned EVP_CIPHER_iv_length(const EVP_CIPHER *cipher) { 580 return cipher->iv_len; 581 } 582 583 uint32_t EVP_CIPHER_flags(const EVP_CIPHER *cipher) { 584 return cipher->flags & ~EVP_CIPH_MODE_MASK; 585 } 586 587 uint32_t EVP_CIPHER_mode(const EVP_CIPHER *cipher) { 588 return cipher->flags & EVP_CIPH_MODE_MASK; 589 } 590 591 int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, 592 const uint8_t *key, const uint8_t *iv, int enc) { 593 if (cipher) { 594 EVP_CIPHER_CTX_init(ctx); 595 } 596 return EVP_CipherInit_ex(ctx, cipher, NULL, key, iv, enc); 597 } 598 599 int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, 600 const uint8_t *key, const uint8_t *iv) { 601 return EVP_CipherInit(ctx, cipher, key, iv, 1); 602 } 603 604 int EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, 605 const uint8_t *key, const uint8_t *iv) { 606 return EVP_CipherInit(ctx, cipher, key, iv, 0); 607 } 608 609 int EVP_add_cipher_alias(const char *a, const char *b) { 610 return 1; 611 } 612