release/src/router/openssl/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 #include <openssl/rand.h>
  64 #ifndef OPENSSL_NO_ENGINE
  65 #include <openssl/engine.h>
  66 #endif
  67 #ifdef OPENSSL_FIPS
  68 #include <openssl/fips.h>
  69 #endif
  70 #include "constant_time_locl.h"
  71 #include "evp_locl.h"
  72
  73 #ifdef OPENSSL_FIPS
  74 #define M_do_cipher(ctx, out, in, inl) FIPS_cipher(ctx, out, in, inl)
  75 #else
  76 #define M_do_cipher(ctx, out, in, inl) ctx->cipher->do_cipher(ctx, out, in, inl)
  77 #endif
  78
  79
  80 const char EVP_version[]="EVP" OPENSSL_VERSION_PTEXT;
  81
  82 void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *ctx)
  83         {
  84         memset(ctx,0,sizeof(EVP_CIPHER_CTX));
  85         /* ctx->cipher=NULL; */
  86         }
  87
  88 EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void)
  89         {
  90         EVP_CIPHER_CTX *ctx=OPENSSL_malloc(sizeof *ctx);
  91         if (ctx)
  92                 EVP_CIPHER_CTX_init(ctx);
  93         return ctx;
  94         }
  95
  96 int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
  97              const unsigned char *key, const unsigned char *iv, int enc)
  98         {
  99         if (cipher)
 100                 EVP_CIPHER_CTX_init(ctx);
 101         return EVP_CipherInit_ex(ctx,cipher,NULL,key,iv,enc);
 102         }
 103
 104 int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,
 105              const unsigned char *key, const unsigned char *iv, int enc)
 106         {
 107         if (enc == -1)
 108                 enc = ctx->encrypt;
 109         else
 110                 {
 111                 if (enc)
 112                         enc = 1;
 113                 ctx->encrypt = enc;
 114                 }
 115 #ifndef OPENSSL_NO_ENGINE
 116         /* Whether it's nice or not, "Inits" can be used on "Final"'d contexts
 117          * so this context may already have an ENGINE! Try to avoid releasing
 118          * the previous handle, re-querying for an ENGINE, and having a
 119          * reinitialisation, when it may all be unecessary. */
 120         if (ctx->engine && ctx->cipher && (!cipher ||
 121                         (cipher && (cipher->nid == ctx->cipher->nid))))
 122                 goto skip_to_init;
 123 #endif
 124         if (cipher)
 125                 {
 126                 /* Ensure a context left lying around from last time is cleared
 127                  * (the previous check attempted to avoid this if the same
 128                  * ENGINE and EVP_CIPHER could be used). */
 129                 if (ctx->cipher)
 130                         {
 131                         unsigned long flags = ctx->flags;
 132                         EVP_CIPHER_CTX_cleanup(ctx);
 133                         /* Restore encrypt and flags */
 134                         ctx->encrypt = enc;
 135                         ctx->flags = flags;
 136                         }
 137 #ifndef OPENSSL_NO_ENGINE
 138                 if(impl)
 139                         {
 140                         if (!ENGINE_init(impl))
 141                                 {
 142                                 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
 143                                 return 0;
 144                                 }
 145                         }
 146                 else
 147                         /* Ask if an ENGINE is reserved for this job */
 148                         impl = ENGINE_get_cipher_engine(cipher->nid);
 149                 if(impl)
 150                         {
 151                         /* There's an ENGINE for this job ... (apparently) */
 152                         const EVP_CIPHER *c = ENGINE_get_cipher(impl, cipher->nid);
 153                         if(!c)
 154                                 {
 155                                 /* One positive side-effect of US's export
 156                                  * control history, is that we should at least
 157                                  * be able to avoid using US mispellings of
 158                                  * "initialisation"? */
 159                                 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
 160                                 return 0;
 161                                 }
 162                         /* We'll use the ENGINE's private cipher definition */
 163                         cipher = c;
 164                         /* Store the ENGINE functional reference so we know
 165                          * 'cipher' came from an ENGINE and we need to release
 166                          * it when done. */
 167                         ctx->engine = impl;
 168                         }
 169                 else
 170                         ctx->engine = NULL;
 171 #endif
 172
 173 #ifdef OPENSSL_FIPS
 174                 if (FIPS_mode())
 175                         return FIPS_cipherinit(ctx, cipher, key, iv, enc);
 176 #endif
 177                 ctx->cipher=cipher;
 178                 if (ctx->cipher->ctx_size)
 179                         {
 180                         ctx->cipher_data=OPENSSL_malloc(ctx->cipher->ctx_size);
 181                         if (!ctx->cipher_data)
 182                                 {
 183                                 EVPerr(EVP_F_EVP_CIPHERINIT_EX, ERR_R_MALLOC_FAILURE);
 184                                 return 0;
 185                                 }
 186                         }
 187                 else
 188                         {
 189                         ctx->cipher_data = NULL;
 190                         }
 191                 ctx->key_len = cipher->key_len;
 192                 ctx->flags = 0;
 193                 if(ctx->cipher->flags & EVP_CIPH_CTRL_INIT)
 194                         {
 195                         if(!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_INIT, 0, NULL))
 196                                 {
 197                                 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
 198                                 return 0;
 199                                 }
 200                         }
 201                 }
 202         else if(!ctx->cipher)
 203                 {
 204                 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_NO_CIPHER_SET);
 205                 return 0;
 206                 }
 207 #ifndef OPENSSL_NO_ENGINE
 208 skip_to_init:
 209 #endif
 210 #ifdef OPENSSL_FIPS
 211         if (FIPS_mode())
 212                 return FIPS_cipherinit(ctx, cipher, key, iv, enc);
 213 #endif
 214         /* we assume block size is a power of 2 in *cryptUpdate */
 215         OPENSSL_assert(ctx->cipher->block_size == 1
 216             || ctx->cipher->block_size == 8
 217             || ctx->cipher->block_size == 16);
 218
 219         if(!(EVP_CIPHER_CTX_flags(ctx) & EVP_CIPH_CUSTOM_IV)) {
 220                 switch(EVP_CIPHER_CTX_mode(ctx)) {
 221
 222                         case EVP_CIPH_STREAM_CIPHER:
 223                         case EVP_CIPH_ECB_MODE:
 224                         break;
 225
 226                         case EVP_CIPH_CFB_MODE:
 227                         case EVP_CIPH_OFB_MODE:
 228
 229                         ctx->num = 0;
 230                         /* fall-through */
 231
 232                         case EVP_CIPH_CBC_MODE:
 233
 234                         OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) <=
 235                                         (int)sizeof(ctx->iv));
 236                         if(iv) memcpy(ctx->oiv, iv, EVP_CIPHER_CTX_iv_length(ctx));
 237                         memcpy(ctx->iv, ctx->oiv, EVP_CIPHER_CTX_iv_length(ctx));
 238                         break;
 239
 240                         case EVP_CIPH_CTR_MODE:
 241                         ctx->num = 0;
 242                         /* Don't reuse IV for CTR mode */
 243                         if(iv)
 244                                 memcpy(ctx->iv, iv, EVP_CIPHER_CTX_iv_length(ctx));
 245                         break;
 246
 247                         default:
 248                         return 0;
 249                         break;
 250                 }
 251         }
 252
 253         if(key || (ctx->cipher->flags & EVP_CIPH_ALWAYS_CALL_INIT)) {
 254                 if(!ctx->cipher->init(ctx,key,iv,enc)) return 0;
 255         }
 256         ctx->buf_len=0;
 257         ctx->final_used=0;
 258         ctx->block_mask=ctx->cipher->block_size-1;
 259         return 1;
 260         }
 261
 262 int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
 263              const unsigned char *in, int inl)
 264         {
 265         if (ctx->encrypt)
 266                 return EVP_EncryptUpdate(ctx,out,outl,in,inl);
 267         else    return EVP_DecryptUpdate(ctx,out,outl,in,inl);
 268         }
 269
 270 int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 271         {
 272         if (ctx->encrypt)
 273                 return EVP_EncryptFinal_ex(ctx,out,outl);
 274         else    return EVP_DecryptFinal_ex(ctx,out,outl);
 275         }
 276
 277 int EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 278         {
 279         if (ctx->encrypt)
 280                 return EVP_EncryptFinal(ctx,out,outl);
 281         else    return EVP_DecryptFinal(ctx,out,outl);
 282         }
 283
 284 int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
 285              const unsigned char *key, const unsigned char *iv)
 286         {
 287         return EVP_CipherInit(ctx, cipher, key, iv, 1);
 288         }
 289
 290 int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx,const EVP_CIPHER *cipher, ENGINE *impl,
 291                 const unsigned char *key, const unsigned char *iv)
 292         {
 293         return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 1);
 294         }
 295
 296 int EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
 297              const unsigned char *key, const unsigned char *iv)
 298         {
 299         return EVP_CipherInit(ctx, cipher, key, iv, 0);
 300         }
 301
 302 int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,
 303              const unsigned char *key, const unsigned char *iv)
 304         {
 305         return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 0);
 306         }
 307
 308 int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
 309              const unsigned char *in, int inl)
 310         {
 311         int i,j,bl;
 312
 313         if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER)
 314                 {
 315                 i = M_do_cipher(ctx, out, in, inl);
 316                 if (i < 0)
 317                         return 0;
 318                 else
 319                         *outl = i;
 320                 return 1;
 321                 }
 322
 323         if (inl <= 0)
 324                 {
 325                 *outl = 0;
 326                 return inl == 0;
 327                 }
 328
 329         if(ctx->buf_len == 0 && (inl&(ctx->block_mask)) == 0)
 330                 {
 331                 if(M_do_cipher(ctx,out,in,inl))
 332                         {
 333                         *outl=inl;
 334                         return 1;
 335                         }
 336                 else
 337                         {
 338                         *outl=0;
 339                         return 0;
 340                         }
 341                 }
 342         i=ctx->buf_len;
 343         bl=ctx->cipher->block_size;
 344         OPENSSL_assert(bl <= (int)sizeof(ctx->buf));
 345         if (i != 0)
 346                 {
 347                 if (i+inl < bl)
 348                         {
 349                         memcpy(&(ctx->buf[i]),in,inl);
 350                         ctx->buf_len+=inl;
 351                         *outl=0;
 352                         return 1;
 353                         }
 354                 else
 355                         {
 356                         j=bl-i;
 357                         memcpy(&(ctx->buf[i]),in,j);
 358                         if(!M_do_cipher(ctx,out,ctx->buf,bl)) return 0;
 359                         inl-=j;
 360                         in+=j;
 361                         out+=bl;
 362                         *outl=bl;
 363                         }
 364                 }
 365         else
 366                 *outl = 0;
 367         i=inl&(bl-1);
 368         inl-=i;
 369         if (inl > 0)
 370                 {
 371                 if(!M_do_cipher(ctx,out,in,inl)) return 0;
 372                 *outl+=inl;
 373                 }
 374
 375         if (i != 0)
 376                 memcpy(ctx->buf,&(in[inl]),i);
 377         ctx->buf_len=i;
 378         return 1;
 379         }
 380
 381 int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 382         {
 383         int ret;
 384         ret = EVP_EncryptFinal_ex(ctx, out, outl);
 385         return ret;
 386         }
 387
 388 int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 389         {
 390         int n,ret;
 391         unsigned int i, b, bl;
 392
 393         if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER)
 394                 {
 395                 ret = M_do_cipher(ctx, out, NULL, 0);
 396                 if (ret < 0)
 397                         return 0;
 398                 else
 399                         *outl = ret;
 400                 return 1;
 401                 }
 402
 403         b=ctx->cipher->block_size;
 404         OPENSSL_assert(b <= sizeof ctx->buf);
 405         if (b == 1)
 406                 {
 407                 *outl=0;
 408                 return 1;
 409                 }
 410         bl=ctx->buf_len;
 411         if (ctx->flags & EVP_CIPH_NO_PADDING)
 412                 {
 413                 if(bl)
 414                         {
 415                         EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
 416                         return 0;
 417                         }
 418                 *outl = 0;
 419                 return 1;
 420                 }
 421
 422         n=b-bl;
 423         for (i=bl; i<b; i++)
 424                 ctx->buf[i]=n;
 425         ret=M_do_cipher(ctx,out,ctx->buf,b);
 426
 427
 428         if(ret)
 429                 *outl=b;
 430
 431         return ret;
 432         }
 433
 434 int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
 435              const unsigned char *in, int inl)
 436         {
 437         int fix_len;
 438         unsigned int b;
 439
 440         if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER)
 441                 {
 442                 fix_len = M_do_cipher(ctx, out, in, inl);
 443                 if (fix_len < 0)
 444                         {
 445                         *outl = 0;
 446                         return 0;
 447                         }
 448                 else
 449                         *outl = fix_len;
 450                 return 1;
 451                 }
 452
 453         if (inl <= 0)
 454                 {
 455                 *outl = 0;
 456                 return inl == 0;
 457                 }
 458
 459         if (ctx->flags & EVP_CIPH_NO_PADDING)
 460                 return EVP_EncryptUpdate(ctx, out, outl, in, inl);
 461
 462         b=ctx->cipher->block_size;
 463         OPENSSL_assert(b <= sizeof ctx->final);
 464
 465         if(ctx->final_used)
 466                 {
 467                 memcpy(out,ctx->final,b);
 468                 out+=b;
 469                 fix_len = 1;
 470                 }
 471         else
 472                 fix_len = 0;
 473
 474
 475         if(!EVP_EncryptUpdate(ctx,out,outl,in,inl))
 476                 return 0;
 477
 478         /* if we have 'decrypted' a multiple of block size, make sure
 479          * we have a copy of this last block */
 480         if (b > 1 && !ctx->buf_len)
 481                 {
 482                 *outl-=b;
 483                 ctx->final_used=1;
 484                 memcpy(ctx->final,&out[*outl],b);
 485                 }
 486         else
 487                 ctx->final_used = 0;
 488
 489         if (fix_len)
 490                 *outl += b;
 491
 492         return 1;
 493         }
 494
 495 int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 496         {
 497         int ret;
 498         ret = EVP_DecryptFinal_ex(ctx, out, outl);
 499         return ret;
 500         }
 501
 502 int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 503         {
 504         unsigned int i, b;
 505         unsigned char pad, padding_good;
 506         *outl=0;
 507
 508         if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER)
 509                 {
 510                 int ret = M_do_cipher(ctx, out, NULL, 0);
 511                 if (ret < 0)
 512                         return 0;
 513                 else
 514                         *outl = ret;
 515                 return 1;
 516                 }
 517
 518         b=(unsigned int)(ctx->cipher->block_size);
 519         if (ctx->flags & EVP_CIPH_NO_PADDING)
 520                 {
 521                 if(ctx->buf_len)
 522                         {
 523                         EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
 524                         return 0;
 525                         }
 526                 *outl = 0;
 527                 return 1;
 528                 }
 529         if (b > 1)
 530                 {
 531                 if (ctx->buf_len || !ctx->final_used)
 532                         {
 533                         EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_WRONG_FINAL_BLOCK_LENGTH);
 534                         return(0);
 535                         }
 536                 OPENSSL_assert(b <= sizeof ctx->final);
 537                 pad=ctx->final[b-1];
 538
 539                 padding_good = (unsigned char)(~constant_time_is_zero_8(pad));
 540                 padding_good &= constant_time_ge_8(b, pad);
 541
 542                 for (i = 1; i < b; ++i)
 543                         {
 544                         unsigned char is_pad_index = constant_time_lt_8(i, pad);
 545                         unsigned char pad_byte_good = constant_time_eq_8(ctx->final[b-i-1], pad);
 546                         padding_good &= constant_time_select_8(is_pad_index, pad_byte_good, 0xff);
 547                         }
 548
 549                 /*
 550                  * At least 1 byte is always padding, so we always write b - 1
 551                  * bytes to avoid a timing leak. The caller is required to have |b|
 552                  * bytes space in |out| by the API contract.
 553                  */
 554                 for (i = 0; i < b - 1; ++i)
 555                         out[i] = ctx->final[i] & padding_good;
 556                 /* Safe cast: for a good padding, EVP_MAX_IV_LENGTH >= b >= pad */
 557                 *outl = padding_good & ((unsigned char)(b - pad));
 558                 return padding_good & 1;
 559                 }
 560         else
 561                 {
 562                 *outl = 0;
 563                 return 1;
 564                 }
 565         }
 566
 567 void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx)
 568         {
 569         if (ctx)
 570                 {
 571                 EVP_CIPHER_CTX_cleanup(ctx);
 572                 OPENSSL_free(ctx);
 573                 }
 574         }
 575
 576 int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *c)
 577         {
 578 #ifndef OPENSSL_FIPS
 579         if (c->cipher != NULL)
 580                 {
 581                 if(c->cipher->cleanup && !c->cipher->cleanup(c))
 582                         return 0;
 583                 /* Cleanse cipher context data */
 584                 if (c->cipher_data)
 585                         OPENSSL_cleanse(c->cipher_data, c->cipher->ctx_size);
 586                 }
 587         if (c->cipher_data)
 588                 OPENSSL_free(c->cipher_data);
 589 #endif
 590 #ifndef OPENSSL_NO_ENGINE
 591         if (c->engine)
 592                 /* The EVP_CIPHER we used belongs to an ENGINE, release the
 593                  * functional reference we held for this reason. */
 594                 ENGINE_finish(c->engine);
 595 #endif
 596 #ifdef OPENSSL_FIPS
 597         FIPS_cipher_ctx_cleanup(c);
 598 #endif
 599         memset(c,0,sizeof(EVP_CIPHER_CTX));
 600         return 1;
 601         }
 602
 603 int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *c, int keylen)
 604         {
 605         if(c->cipher->flags & EVP_CIPH_CUSTOM_KEY_LENGTH)
 606                 return EVP_CIPHER_CTX_ctrl(c, EVP_CTRL_SET_KEY_LENGTH, keylen, NULL);
 607         if(c->key_len == keylen) return 1;
 608         if((keylen > 0) && (c->cipher->flags & EVP_CIPH_VARIABLE_LENGTH))
 609                 {
 610                 c->key_len = keylen;
 611                 return 1;
 612                 }
 613         EVPerr(EVP_F_EVP_CIPHER_CTX_SET_KEY_LENGTH,EVP_R_INVALID_KEY_LENGTH);
 614         return 0;
 615         }
 616
 617 int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad)
 618         {
 619         if (pad) ctx->flags &= ~EVP_CIPH_NO_PADDING;
 620         else ctx->flags |= EVP_CIPH_NO_PADDING;
 621         return 1;
 622         }
 623
 624 int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr)
 625 {
 626         int ret;
 627         if(!ctx->cipher) {
 628                 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_NO_CIPHER_SET);
 629                 return 0;
 630         }
 631
 632         if(!ctx->cipher->ctrl) {
 633                 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_NOT_IMPLEMENTED);
 634                 return 0;
 635         }
 636
 637         ret = ctx->cipher->ctrl(ctx, type, arg, ptr);
 638         if(ret == -1) {
 639                 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_OPERATION_NOT_IMPLEMENTED);
 640                 return 0;
 641         }
 642         return ret;
 643 }
 644
 645 int EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX *ctx, unsigned char *key)
 646         {
 647         if (ctx->cipher->flags & EVP_CIPH_RAND_KEY)
 648                 return EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_RAND_KEY, 0, key);
 649         if (RAND_bytes(key, ctx->key_len) <= 0)
 650                 return 0;
 651         return 1;
 652         }
 653
 654 int EVP_CIPHER_CTX_copy(EVP_CIPHER_CTX *out, const EVP_CIPHER_CTX *in)
 655         {
 656         if ((in == NULL) || (in->cipher == NULL))
 657                 {
 658                 EVPerr(EVP_F_EVP_CIPHER_CTX_COPY,EVP_R_INPUT_NOT_INITIALIZED);
 659                 return 0;
 660                 }
 661 #ifndef OPENSSL_NO_ENGINE
 662         /* Make sure it's safe to copy a cipher context using an ENGINE */
 663         if (in->engine && !ENGINE_init(in->engine))
 664                 {
 665                 EVPerr(EVP_F_EVP_CIPHER_CTX_COPY,ERR_R_ENGINE_LIB);
 666                 return 0;
 667                 }
 668 #endif
 669
 670         EVP_CIPHER_CTX_cleanup(out);
 671         memcpy(out,in,sizeof *out);
 672
 673         if (in->cipher_data && in->cipher->ctx_size)
 674                 {
 675                 out->cipher_data=OPENSSL_malloc(in->cipher->ctx_size);
 676                 if (!out->cipher_data)
 677                         {
 678                         EVPerr(EVP_F_EVP_CIPHER_CTX_COPY,ERR_R_MALLOC_FAILURE);
 679                         return 0;
 680                         }
 681                 memcpy(out->cipher_data,in->cipher_data,in->cipher->ctx_size);
 682                 }
 683
 684         if (in->cipher->flags & EVP_CIPH_CUSTOM_COPY)
 685                 return in->cipher->ctrl((EVP_CIPHER_CTX *)in, EVP_CTRL_COPY, 0, out);
 686         return 1;
 687         }