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