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