crypto/openssl-0.9.7e/crypto/evp/evp_enc.c

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