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                 ctx->cipher_data=OPENSSL_malloc(ctx->cipher->ctx_size);
 152                 ctx->key_len = cipher->key_len;
 153                 ctx->flags = 0;
 154                 if(ctx->cipher->flags & EVP_CIPH_CTRL_INIT)
 155                         {
 156                         if(!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_INIT, 0, NULL))
 157                                 {
 158                                 EVPerr(EVP_F_EVP_CIPHERINIT, EVP_R_INITIALIZATION_ERROR);
 159                                 return 0;
 160                                 }
 161                         }
 162                 }
 163         else if(!ctx->cipher)
 164                 {
 165                 EVPerr(EVP_F_EVP_CIPHERINIT, EVP_R_NO_CIPHER_SET);
 166                 return 0;
 167                 }
 168 #ifndef OPENSSL_NO_ENGINE
 169 skip_to_init:
 170 #endif
 171         /* we assume block size is a power of 2 in *cryptUpdate */
 172         OPENSSL_assert(ctx->cipher->block_size == 1
 173             || ctx->cipher->block_size == 8
 174             || ctx->cipher->block_size == 16);
 175
 176         if(!(EVP_CIPHER_CTX_flags(ctx) & EVP_CIPH_CUSTOM_IV)) {
 177                 switch(EVP_CIPHER_CTX_mode(ctx)) {
 178
 179                         case EVP_CIPH_STREAM_CIPHER:
 180                         case EVP_CIPH_ECB_MODE:
 181                         break;
 182
 183                         case EVP_CIPH_CFB_MODE:
 184                         case EVP_CIPH_OFB_MODE:
 185
 186                         ctx->num = 0;
 187
 188                         case EVP_CIPH_CBC_MODE:
 189
 190                         OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) <= sizeof ctx->iv);
 191                         if(iv) memcpy(ctx->oiv, iv, EVP_CIPHER_CTX_iv_length(ctx));
 192                         memcpy(ctx->iv, ctx->oiv, EVP_CIPHER_CTX_iv_length(ctx));
 193                         break;
 194
 195                         default:
 196                         return 0;
 197                         break;
 198                 }
 199         }
 200
 201         if(key || (ctx->cipher->flags & EVP_CIPH_ALWAYS_CALL_INIT)) {
 202                 if(!ctx->cipher->init(ctx,key,iv,enc)) return 0;
 203         }
 204         ctx->buf_len=0;
 205         ctx->final_used=0;
 206         ctx->block_mask=ctx->cipher->block_size-1;
 207         return 1;
 208         }
 209
 210 int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
 211              const unsigned char *in, int inl)
 212         {
 213         if (ctx->encrypt)
 214                 return EVP_EncryptUpdate(ctx,out,outl,in,inl);
 215         else    return EVP_DecryptUpdate(ctx,out,outl,in,inl);
 216         }
 217
 218 int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 219         {
 220         if (ctx->encrypt)
 221                 return EVP_EncryptFinal_ex(ctx,out,outl);
 222         else    return EVP_DecryptFinal_ex(ctx,out,outl);
 223         }
 224
 225 int EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 226         {
 227         if (ctx->encrypt)
 228                 return EVP_EncryptFinal(ctx,out,outl);
 229         else    return EVP_DecryptFinal(ctx,out,outl);
 230         }
 231
 232 int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
 233              const unsigned char *key, const unsigned char *iv)
 234         {
 235         return EVP_CipherInit(ctx, cipher, key, iv, 1);
 236         }
 237
 238 int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx,const EVP_CIPHER *cipher, ENGINE *impl,
 239                 const unsigned char *key, const unsigned char *iv)
 240         {
 241         return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 1);
 242         }
 243
 244 int EVP_DecryptInit(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, 0);
 248         }
 249
 250 int EVP_DecryptInit_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, 0);
 254         }
 255
 256 int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
 257              const unsigned char *in, int inl)
 258         {
 259         int i,j,bl;
 260
 261         OPENSSL_assert(inl > 0);
 262         if(ctx->buf_len == 0 && (inl&(ctx->block_mask)) == 0)
 263                 {
 264                 if(ctx->cipher->do_cipher(ctx,out,in,inl))
 265                         {
 266                         *outl=inl;
 267                         return 1;
 268                         }
 269                 else
 270                         {
 271                         *outl=0;
 272                         return 0;
 273                         }
 274                 }
 275         i=ctx->buf_len;
 276         bl=ctx->cipher->block_size;
 277         OPENSSL_assert(bl <= sizeof ctx->buf);
 278         if (i != 0)
 279                 {
 280                 if (i+inl < bl)
 281                         {
 282                         memcpy(&(ctx->buf[i]),in,inl);
 283                         ctx->buf_len+=inl;
 284                         *outl=0;
 285                         return 1;
 286                         }
 287                 else
 288                         {
 289                         j=bl-i;
 290                         memcpy(&(ctx->buf[i]),in,j);
 291                         if(!ctx->cipher->do_cipher(ctx,out,ctx->buf,bl)) return 0;
 292                         inl-=j;
 293                         in+=j;
 294                         out+=bl;
 295                         *outl=bl;
 296                         }
 297                 }
 298         else
 299                 *outl = 0;
 300         i=inl&(bl-1);
 301         inl-=i;
 302         if (inl > 0)
 303                 {
 304                 if(!ctx->cipher->do_cipher(ctx,out,in,inl)) return 0;
 305                 *outl+=inl;
 306                 }
 307
 308         if (i != 0)
 309                 memcpy(ctx->buf,&(in[inl]),i);
 310         ctx->buf_len=i;
 311         return 1;
 312         }
 313
 314 int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 315         {
 316         int ret;
 317         ret = EVP_EncryptFinal_ex(ctx, out, outl);
 318         return ret;
 319         }
 320
 321 int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 322         {
 323         int i,n,b,bl,ret;
 324
 325         b=ctx->cipher->block_size;
 326         OPENSSL_assert(b <= sizeof ctx->buf);
 327         if (b == 1)
 328                 {
 329                 *outl=0;
 330                 return 1;
 331                 }
 332         bl=ctx->buf_len;
 333         if (ctx->flags & EVP_CIPH_NO_PADDING)
 334                 {
 335                 if(bl)
 336                         {
 337                         EVPerr(EVP_F_EVP_ENCRYPTFINAL,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
 338                         return 0;
 339                         }
 340                 *outl = 0;
 341                 return 1;
 342                 }
 343
 344         n=b-bl;
 345         for (i=bl; i<b; i++)
 346                 ctx->buf[i]=n;
 347         ret=ctx->cipher->do_cipher(ctx,out,ctx->buf,b);
 348
 349
 350         if(ret)
 351                 *outl=b;
 352
 353         return ret;
 354         }
 355
 356 int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
 357              const unsigned char *in, int inl)
 358         {
 359         int b, fix_len;
 360
 361         if (inl == 0)
 362                 {
 363                 *outl=0;
 364                 return 1;
 365                 }
 366
 367         if (ctx->flags & EVP_CIPH_NO_PADDING)
 368                 return EVP_EncryptUpdate(ctx, out, outl, in, inl);
 369
 370         b=ctx->cipher->block_size;
 371         OPENSSL_assert(b <= sizeof ctx->final);
 372
 373         if(ctx->final_used)
 374                 {
 375                 memcpy(out,ctx->final,b);
 376                 out+=b;
 377                 fix_len = 1;
 378                 }
 379         else
 380                 fix_len = 0;
 381
 382
 383         if(!EVP_EncryptUpdate(ctx,out,outl,in,inl))
 384                 return 0;
 385
 386         /* if we have 'decrypted' a multiple of block size, make sure
 387          * we have a copy of this last block */
 388         if (b > 1 && !ctx->buf_len)
 389                 {
 390                 *outl-=b;
 391                 ctx->final_used=1;
 392                 memcpy(ctx->final,&out[*outl],b);
 393                 }
 394         else
 395                 ctx->final_used = 0;
 396
 397         if (fix_len)
 398                 *outl += b;
 399
 400         return 1;
 401         }
 402
 403 int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 404         {
 405         int ret;
 406         ret = EVP_DecryptFinal_ex(ctx, out, outl);
 407         return ret;
 408         }
 409
 410 int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 411         {
 412         int i,b;
 413         int n;
 414
 415         *outl=0;
 416         b=ctx->cipher->block_size;
 417         if (ctx->flags & EVP_CIPH_NO_PADDING)
 418                 {
 419                 if(ctx->buf_len)
 420                         {
 421                         EVPerr(EVP_F_EVP_DECRYPTFINAL,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
 422                         return 0;
 423                         }
 424                 *outl = 0;
 425                 return 1;
 426                 }
 427         if (b > 1)
 428                 {
 429                 if (ctx->buf_len || !ctx->final_used)
 430                         {
 431                         EVPerr(EVP_F_EVP_DECRYPTFINAL,EVP_R_WRONG_FINAL_BLOCK_LENGTH);
 432                         return(0);
 433                         }
 434                 OPENSSL_assert(b <= sizeof ctx->final);
 435                 n=ctx->final[b-1];
 436                 if (n > b)
 437                         {
 438                         EVPerr(EVP_F_EVP_DECRYPTFINAL,EVP_R_BAD_DECRYPT);
 439                         return(0);
 440                         }
 441                 for (i=0; i<n; i++)
 442                         {
 443                         if (ctx->final[--b] != n)
 444                                 {
 445                                 EVPerr(EVP_F_EVP_DECRYPTFINAL,EVP_R_BAD_DECRYPT);
 446                                 return(0);
 447                                 }
 448                         }
 449                 n=ctx->cipher->block_size-n;
 450                 for (i=0; i<n; i++)
 451                         out[i]=ctx->final[i];
 452                 *outl=n;
 453                 }
 454         else
 455                 *outl=0;
 456         return(1);
 457         }
 458
 459 int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *c)
 460         {
 461         if (c->cipher != NULL)
 462                 {
 463                 if(c->cipher->cleanup && !c->cipher->cleanup(c))
 464                         return 0;
 465                 /* Cleanse cipher context data */
 466                 if (c->cipher_data)
 467                         OPENSSL_cleanse(c->cipher_data, c->cipher->ctx_size);
 468                 }
 469         if (c->cipher_data)
 470                 OPENSSL_free(c->cipher_data);
 471 #ifndef OPENSSL_NO_ENGINE
 472         if (c->engine)
 473                 /* The EVP_CIPHER we used belongs to an ENGINE, release the
 474                  * functional reference we held for this reason. */
 475                 ENGINE_finish(c->engine);
 476 #endif
 477         memset(c,0,sizeof(EVP_CIPHER_CTX));
 478         return 1;
 479         }
 480
 481 int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *c, int keylen)
 482         {
 483         if(c->cipher->flags & EVP_CIPH_CUSTOM_KEY_LENGTH)
 484                 return EVP_CIPHER_CTX_ctrl(c, EVP_CTRL_SET_KEY_LENGTH, keylen, NULL);
 485         if(c->key_len == keylen) return 1;
 486         if((keylen > 0) && (c->cipher->flags & EVP_CIPH_VARIABLE_LENGTH))
 487                 {
 488                 c->key_len = keylen;
 489                 return 1;
 490                 }
 491         EVPerr(EVP_F_EVP_CIPHER_CTX_SET_KEY_LENGTH,EVP_R_INVALID_KEY_LENGTH);
 492         return 0;
 493         }
 494
 495 int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad)
 496         {
 497         if (pad) ctx->flags &= ~EVP_CIPH_NO_PADDING;
 498         else ctx->flags |= EVP_CIPH_NO_PADDING;
 499         return 1;
 500         }
 501
 502 int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr)
 503 {
 504         int ret;
 505         if(!ctx->cipher) {
 506                 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_NO_CIPHER_SET);
 507                 return 0;
 508         }
 509
 510         if(!ctx->cipher->ctrl) {
 511                 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_NOT_IMPLEMENTED);
 512                 return 0;
 513         }
 514
 515         ret = ctx->cipher->ctrl(ctx, type, arg, ptr);
 516         if(ret == -1) {
 517                 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_OPERATION_NOT_IMPLEMENTED);
 518                 return 0;
 519         }
 520         return ret;
 521 }