1 /* crypto/evp/evp_enc.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 #include <stdio.h> 60 #include "cryptlib.h" 61 #include <openssl/evp.h> 62 #include <openssl/err.h> 63 #include <openssl/rand.h> 64 #ifndef OPENSSL_NO_ENGINE 65 #include <openssl/engine.h> 66 #endif 67 #include "evp_locl.h" 68 69 const char EVP_version[]="EVP" OPENSSL_VERSION_PTEXT; 70 71 void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *ctx) 72 { 73 memset(ctx,0,sizeof(EVP_CIPHER_CTX)); 74 /* ctx->cipher=NULL; */ 75 } 76 77 EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void) 78 { 79 EVP_CIPHER_CTX *ctx=OPENSSL_malloc(sizeof *ctx); 80 if (ctx) 81 EVP_CIPHER_CTX_init(ctx); 82 return ctx; 83 } 84 85 int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, 86 const unsigned char *key, const unsigned char *iv, int enc) 87 { 88 if (cipher) 89 EVP_CIPHER_CTX_init(ctx); 90 return EVP_CipherInit_ex(ctx,cipher,NULL,key,iv,enc); 91 } 92 93 int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl, 94 const unsigned char *key, const unsigned char *iv, int enc) 95 { 96 if (enc == -1) 97 enc = ctx->encrypt; 98 else 99 { 100 if (enc) 101 enc = 1; 102 ctx->encrypt = enc; 103 } 104 #ifndef OPENSSL_NO_ENGINE 105 /* Whether it's nice or not, "Inits" can be used on "Final"'d contexts 106 * so this context may already have an ENGINE! Try to avoid releasing 107 * the previous handle, re-querying for an ENGINE, and having a 108 * reinitialisation, when it may all be unecessary. */ 109 if (ctx->engine && ctx->cipher && (!cipher || 110 (cipher && (cipher->nid == ctx->cipher->nid)))) 111 goto skip_to_init; 112 #endif 113 if (cipher) 114 { 115 /* Ensure a context left lying around from last time is cleared 116 * (the previous check attempted to avoid this if the same 117 * ENGINE and EVP_CIPHER could be used). */ 118 EVP_CIPHER_CTX_cleanup(ctx); 119 120 /* Restore encrypt field: it is zeroed by cleanup */ 121 ctx->encrypt = enc; 122 #ifndef OPENSSL_NO_ENGINE 123 if(impl) 124 { 125 if (!ENGINE_init(impl)) 126 { 127 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR); 128 return 0; 129 } 130 } 131 else 132 /* Ask if an ENGINE is reserved for this job */ 133 impl = ENGINE_get_cipher_engine(cipher->nid); 134 if(impl) 135 { 136 /* There's an ENGINE for this job ... (apparently) */ 137 const EVP_CIPHER *c = ENGINE_get_cipher(impl, cipher->nid); 138 if(!c) 139 { 140 /* One positive side-effect of US's export 141 * control history, is that we should at least 142 * be able to avoid using US mispellings of 143 * "initialisation"? */ 144 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR); 145 return 0; 146 } 147 /* We'll use the ENGINE's private cipher definition */ 148 cipher = c; 149 /* Store the ENGINE functional reference so we know 150 * 'cipher' came from an ENGINE and we need to release 151 * it when done. */ 152 ctx->engine = impl; 153 } 154 else 155 ctx->engine = NULL; 156 #endif 157 158 ctx->cipher=cipher; 159 if (ctx->cipher->ctx_size) 160 { 161 ctx->cipher_data=OPENSSL_malloc(ctx->cipher->ctx_size); 162 if (!ctx->cipher_data) 163 { 164 EVPerr(EVP_F_EVP_CIPHERINIT_EX, ERR_R_MALLOC_FAILURE); 165 return 0; 166 } 167 } 168 else 169 { 170 ctx->cipher_data = NULL; 171 } 172 ctx->key_len = cipher->key_len; 173 ctx->flags = 0; 174 if(ctx->cipher->flags & EVP_CIPH_CTRL_INIT) 175 { 176 if(!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_INIT, 0, NULL)) 177 { 178 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR); 179 return 0; 180 } 181 } 182 } 183 else if(!ctx->cipher) 184 { 185 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_NO_CIPHER_SET); 186 return 0; 187 } 188 #ifndef OPENSSL_NO_ENGINE 189 skip_to_init: 190 #endif 191 /* we assume block size is a power of 2 in *cryptUpdate */ 192 OPENSSL_assert(ctx->cipher->block_size == 1 193 || ctx->cipher->block_size == 8 194 || ctx->cipher->block_size == 16); 195 196 if(!(EVP_CIPHER_CTX_flags(ctx) & EVP_CIPH_CUSTOM_IV)) { 197 switch(EVP_CIPHER_CTX_mode(ctx)) { 198 199 case EVP_CIPH_STREAM_CIPHER: 200 case EVP_CIPH_ECB_MODE: 201 break; 202 203 case EVP_CIPH_CFB_MODE: 204 case EVP_CIPH_OFB_MODE: 205 206 ctx->num = 0; 207 208 case EVP_CIPH_CBC_MODE: 209 210 OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) <= 211 (int)sizeof(ctx->iv)); 212 if(iv) memcpy(ctx->oiv, iv, EVP_CIPHER_CTX_iv_length(ctx)); 213 memcpy(ctx->iv, ctx->oiv, EVP_CIPHER_CTX_iv_length(ctx)); 214 break; 215 216 default: 217 return 0; 218 break; 219 } 220 } 221 222 if(key || (ctx->cipher->flags & EVP_CIPH_ALWAYS_CALL_INIT)) { 223 if(!ctx->cipher->init(ctx,key,iv,enc)) return 0; 224 } 225 ctx->buf_len=0; 226 ctx->final_used=0; 227 ctx->block_mask=ctx->cipher->block_size-1; 228 return 1; 229 } 230 231 int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl, 232 const unsigned char *in, int inl) 233 { 234 if (ctx->encrypt) 235 return EVP_EncryptUpdate(ctx,out,outl,in,inl); 236 else return EVP_DecryptUpdate(ctx,out,outl,in,inl); 237 } 238 239 int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl) 240 { 241 if (ctx->encrypt) 242 return EVP_EncryptFinal_ex(ctx,out,outl); 243 else return EVP_DecryptFinal_ex(ctx,out,outl); 244 } 245 246 int EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl) 247 { 248 if (ctx->encrypt) 249 return EVP_EncryptFinal(ctx,out,outl); 250 else return EVP_DecryptFinal(ctx,out,outl); 251 } 252 253 int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, 254 const unsigned char *key, const unsigned char *iv) 255 { 256 return EVP_CipherInit(ctx, cipher, key, iv, 1); 257 } 258 259 int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx,const EVP_CIPHER *cipher, ENGINE *impl, 260 const unsigned char *key, const unsigned char *iv) 261 { 262 return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 1); 263 } 264 265 int EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, 266 const unsigned char *key, const unsigned char *iv) 267 { 268 return EVP_CipherInit(ctx, cipher, key, iv, 0); 269 } 270 271 int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl, 272 const unsigned char *key, const unsigned char *iv) 273 { 274 return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 0); 275 } 276 277 int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl, 278 const unsigned char *in, int inl) 279 { 280 int i,j,bl; 281 282 if (inl <= 0) 283 { 284 *outl = 0; 285 return inl == 0; 286 } 287 288 if(ctx->buf_len == 0 && (inl&(ctx->block_mask)) == 0) 289 { 290 if(ctx->cipher->do_cipher(ctx,out,in,inl)) 291 { 292 *outl=inl; 293 return 1; 294 } 295 else 296 { 297 *outl=0; 298 return 0; 299 } 300 } 301 i=ctx->buf_len; 302 bl=ctx->cipher->block_size; 303 OPENSSL_assert(bl <= (int)sizeof(ctx->buf)); 304 if (i != 0) 305 { 306 if (i+inl < bl) 307 { 308 memcpy(&(ctx->buf[i]),in,inl); 309 ctx->buf_len+=inl; 310 *outl=0; 311 return 1; 312 } 313 else 314 { 315 j=bl-i; 316 memcpy(&(ctx->buf[i]),in,j); 317 if(!ctx->cipher->do_cipher(ctx,out,ctx->buf,bl)) return 0; 318 inl-=j; 319 in+=j; 320 out+=bl; 321 *outl=bl; 322 } 323 } 324 else 325 *outl = 0; 326 i=inl&(bl-1); 327 inl-=i; 328 if (inl > 0) 329 { 330 if(!ctx->cipher->do_cipher(ctx,out,in,inl)) return 0; 331 *outl+=inl; 332 } 333 334 if (i != 0) 335 memcpy(ctx->buf,&(in[inl]),i); 336 ctx->buf_len=i; 337 return 1; 338 } 339 340 int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl) 341 { 342 int ret; 343 ret = EVP_EncryptFinal_ex(ctx, out, outl); 344 return ret; 345 } 346 347 int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl) 348 { 349 int n,ret; 350 unsigned int i, b, bl; 351 352 b=ctx->cipher->block_size; 353 OPENSSL_assert(b <= sizeof ctx->buf); 354 if (b == 1) 355 { 356 *outl=0; 357 return 1; 358 } 359 bl=ctx->buf_len; 360 if (ctx->flags & EVP_CIPH_NO_PADDING) 361 { 362 if(bl) 363 { 364 EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH); 365 return 0; 366 } 367 *outl = 0; 368 return 1; 369 } 370 371 n=b-bl; 372 for (i=bl; i<b; i++) 373 ctx->buf[i]=n; 374 ret=ctx->cipher->do_cipher(ctx,out,ctx->buf,b); 375 376 377 if(ret) 378 *outl=b; 379 380 return ret; 381 } 382 383 int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl, 384 const unsigned char *in, int inl) 385 { 386 int fix_len; 387 unsigned int b; 388 389 if (inl <= 0) 390 { 391 *outl = 0; 392 return inl == 0; 393 } 394 395 if (ctx->flags & EVP_CIPH_NO_PADDING) 396 return EVP_EncryptUpdate(ctx, out, outl, in, inl); 397 398 b=ctx->cipher->block_size; 399 OPENSSL_assert(b <= sizeof ctx->final); 400 401 if(ctx->final_used) 402 { 403 memcpy(out,ctx->final,b); 404 out+=b; 405 fix_len = 1; 406 } 407 else 408 fix_len = 0; 409 410 411 if(!EVP_EncryptUpdate(ctx,out,outl,in,inl)) 412 return 0; 413 414 /* if we have 'decrypted' a multiple of block size, make sure 415 * we have a copy of this last block */ 416 if (b > 1 && !ctx->buf_len) 417 { 418 *outl-=b; 419 ctx->final_used=1; 420 memcpy(ctx->final,&out[*outl],b); 421 } 422 else 423 ctx->final_used = 0; 424 425 if (fix_len) 426 *outl += b; 427 428 return 1; 429 } 430 431 int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl) 432 { 433 int ret; 434 ret = EVP_DecryptFinal_ex(ctx, out, outl); 435 return ret; 436 } 437 438 int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl) 439 { 440 int i,n; 441 unsigned int b; 442 443 *outl=0; 444 b=ctx->cipher->block_size; 445 if (ctx->flags & EVP_CIPH_NO_PADDING) 446 { 447 if(ctx->buf_len) 448 { 449 EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH); 450 return 0; 451 } 452 *outl = 0; 453 return 1; 454 } 455 if (b > 1) 456 { 457 if (ctx->buf_len || !ctx->final_used) 458 { 459 EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_WRONG_FINAL_BLOCK_LENGTH); 460 return(0); 461 } 462 OPENSSL_assert(b <= sizeof ctx->final); 463 n=ctx->final[b-1]; 464 if (n == 0 || n > (int)b) 465 { 466 EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_BAD_DECRYPT); 467 return(0); 468 } 469 for (i=0; i<n; i++) 470 { 471 if (ctx->final[--b] != n) 472 { 473 EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_BAD_DECRYPT); 474 return(0); 475 } 476 } 477 n=ctx->cipher->block_size-n; 478 for (i=0; i<n; i++) 479 out[i]=ctx->final[i]; 480 *outl=n; 481 } 482 else 483 *outl=0; 484 return(1); 485 } 486 487 void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx) 488 { 489 if (ctx) 490 { 491 EVP_CIPHER_CTX_cleanup(ctx); 492 OPENSSL_free(ctx); 493 } 494 } 495 496 int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *c) 497 { 498 if (c->cipher != NULL) 499 { 500 if(c->cipher->cleanup && !c->cipher->cleanup(c)) 501 return 0; 502 /* Cleanse cipher context data */ 503 if (c->cipher_data) 504 OPENSSL_cleanse(c->cipher_data, c->cipher->ctx_size); 505 } 506 if (c->cipher_data) 507 OPENSSL_free(c->cipher_data); 508 #ifndef OPENSSL_NO_ENGINE 509 if (c->engine) 510 /* The EVP_CIPHER we used belongs to an ENGINE, release the 511 * functional reference we held for this reason. */ 512 ENGINE_finish(c->engine); 513 #endif 514 memset(c,0,sizeof(EVP_CIPHER_CTX)); 515 return 1; 516 } 517 518 int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *c, int keylen) 519 { 520 if(c->cipher->flags & EVP_CIPH_CUSTOM_KEY_LENGTH) 521 return EVP_CIPHER_CTX_ctrl(c, EVP_CTRL_SET_KEY_LENGTH, keylen, NULL); 522 if(c->key_len == keylen) return 1; 523 if((keylen > 0) && (c->cipher->flags & EVP_CIPH_VARIABLE_LENGTH)) 524 { 525 c->key_len = keylen; 526 return 1; 527 } 528 EVPerr(EVP_F_EVP_CIPHER_CTX_SET_KEY_LENGTH,EVP_R_INVALID_KEY_LENGTH); 529 return 0; 530 } 531 532 int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad) 533 { 534 if (pad) ctx->flags &= ~EVP_CIPH_NO_PADDING; 535 else ctx->flags |= EVP_CIPH_NO_PADDING; 536 return 1; 537 } 538 539 int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr) 540 { 541 int ret; 542 if(!ctx->cipher) { 543 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_NO_CIPHER_SET); 544 return 0; 545 } 546 547 if(!ctx->cipher->ctrl) { 548 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_NOT_IMPLEMENTED); 549 return 0; 550 } 551 552 ret = ctx->cipher->ctrl(ctx, type, arg, ptr); 553 if(ret == -1) { 554 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_OPERATION_NOT_IMPLEMENTED); 555 return 0; 556 } 557 return ret; 558 } 559 560 int EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX *ctx, unsigned char *key) 561 { 562 if (ctx->cipher->flags & EVP_CIPH_RAND_KEY) 563 return EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_RAND_KEY, 0, key); 564 if (RAND_bytes(key, ctx->key_len) <= 0) 565 return 0; 566 return 1; 567 } 568 569