crypto/evp/evp_enc.c

   1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
   2  * All rights reserved.
   3  *
   4  * This package is an SSL implementation written
   5  * by Eric Young (eay@cryptsoft.com).
   6  * The implementation was written so as to conform with Netscapes SSL.
   7  *
   8  * This library is free for commercial and non-commercial use as long as
   9  * the following conditions are aheared to.  The following conditions
  10  * apply to all code found in this distribution, be it the RC4, RSA,
  11  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  12  * included with this distribution is covered by the same copyright terms
  13  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  14  *
  15  * Copyright remains Eric Young's, and as such any Copyright notices in
  16  * the code are not to be removed.
  17  * If this package is used in a product, Eric Young should be given attribution
  18  * as the author of the parts of the library used.
  19  * This can be in the form of a textual message at program startup or
  20  * in documentation (online or textual) provided with the package.
  21  *
  22  * Redistribution and use in source and binary forms, with or without
  23  * modification, are permitted provided that the following conditions
  24  * are met:
  25  * 1. Redistributions of source code must retain the copyright
  26  *    notice, this list of conditions and the following disclaimer.
  27  * 2. Redistributions in binary form must reproduce the above copyright
  28  *    notice, this list of conditions and the following disclaimer in the
  29  *    documentation and/or other materials provided with the distribution.
  30  * 3. All advertising materials mentioning features or use of this software
  31  *    must display the following acknowledgement:
  32  *    "This product includes cryptographic software written by
  33  *     Eric Young (eay@cryptsoft.com)"
  34  *    The word 'cryptographic' can be left out if the rouines from the library
  35  *    being used are not cryptographic related :-).
  36  * 4. If you include any Windows specific code (or a derivative thereof) from
  37  *    the apps directory (application code) you must include an acknowledgement:
  38  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  39  *
  40  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  41  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  43  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  44  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  45  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  46  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  48  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  49  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  50  * SUCH DAMAGE.
  51  *
  52  * The licence and distribution terms for any publically available version or
  53  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  54  * copied and put under another distribution licence
  55  * [including the GNU Public Licence.]
  56  */
  57
  58 #include <stdio.h>
  59 #include "internal/cryptlib.h"
  60 #include <openssl/evp.h>
  61 #include <openssl/err.h>
  62 #include <openssl/rand.h>
  63 #include <openssl/engine.h>
  64 #include "internal/evp_int.h"
  65 #include "evp_locl.h"
  66
  67 int EVP_CIPHER_CTX_reset(EVP_CIPHER_CTX *c)
  68 {
  69     if (c == NULL)
  70         return 1;
  71     if (c->cipher != NULL) {
  72         if (c->cipher->cleanup && !c->cipher->cleanup(c))
  73             return 0;
  74         /* Cleanse cipher context data */
  75         if (c->cipher_data && c->cipher->ctx_size)
  76             OPENSSL_cleanse(c->cipher_data, c->cipher->ctx_size);
  77     }
  78     OPENSSL_free(c->cipher_data);
  79 #ifndef OPENSSL_NO_ENGINE
  80     ENGINE_finish(c->engine);
  81 #endif
  82     memset(c, 0, sizeof(*c));
  83     return 1;
  84 }
  85
  86 EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void)
  87 {
  88     return OPENSSL_zalloc(sizeof(EVP_CIPHER_CTX));
  89 }
  90
  91 void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx)
  92 {
  93     EVP_CIPHER_CTX_reset(ctx);
  94     OPENSSL_free(ctx);
  95 }
  96
  97 int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
  98                    const unsigned char *key, const unsigned char *iv, int enc)
  99 {
 100     EVP_CIPHER_CTX_reset(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,
 105                       ENGINE *impl, const unsigned char *key,
 106                       const unsigned char *iv, int enc)
 107 {
 108     if (enc == -1)
 109         enc = ctx->encrypt;
 110     else {
 111         if (enc)
 112             enc = 1;
 113         ctx->encrypt = enc;
 114     }
 115 #ifndef OPENSSL_NO_ENGINE
 116     /*
 117      * Whether it's nice or not, "Inits" can be used on "Final"'d contexts so
 118      * this context may already have an ENGINE! Try to avoid releasing the
 119      * previous handle, re-querying for an ENGINE, and having a
 120      * reinitialisation, when it may all be unnecessary.
 121      */
 122     if (ctx->engine && ctx->cipher
 123         && (cipher == NULL || cipher->nid == ctx->cipher->nid))
 124         goto skip_to_init;
 125 #endif
 126     if (cipher) {
 127         /*
 128          * Ensure a context left lying around from last time is cleared (the
 129          * previous check attempted to avoid this if the same ENGINE and
 130          * EVP_CIPHER could be used).
 131          */
 132         if (ctx->cipher) {
 133             unsigned long flags = ctx->flags;
 134             EVP_CIPHER_CTX_reset(ctx);
 135             /* Restore encrypt and flags */
 136             ctx->encrypt = enc;
 137             ctx->flags = flags;
 138         }
 139 #ifndef OPENSSL_NO_ENGINE
 140         if (impl) {
 141             if (!ENGINE_init(impl)) {
 142                 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
 143                 return 0;
 144             }
 145         } else
 146             /* Ask if an ENGINE is reserved for this job */
 147             impl = ENGINE_get_cipher_engine(cipher->nid);
 148         if (impl) {
 149             /* There's an ENGINE for this job ... (apparently) */
 150             const EVP_CIPHER *c = ENGINE_get_cipher(impl, cipher->nid);
 151             if (!c) {
 152                 /*
 153                  * One positive side-effect of US's export control history,
 154                  * is that we should at least be able to avoid using US
 155                  * misspellings of "initialisation"?
 156                  */
 157                 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
 158                 return 0;
 159             }
 160             /* We'll use the ENGINE's private cipher definition */
 161             cipher = c;
 162             /*
 163              * Store the ENGINE functional reference so we know 'cipher' came
 164              * from an ENGINE and we need to release it when done.
 165              */
 166             ctx->engine = impl;
 167         } else
 168             ctx->engine = NULL;
 169 #endif
 170
 171         ctx->cipher = cipher;
 172         if (ctx->cipher->ctx_size) {
 173             ctx->cipher_data = OPENSSL_zalloc(ctx->cipher->ctx_size);
 174             if (ctx->cipher_data == NULL) {
 175                 EVPerr(EVP_F_EVP_CIPHERINIT_EX, ERR_R_MALLOC_FAILURE);
 176                 return 0;
 177             }
 178         } else {
 179             ctx->cipher_data = NULL;
 180         }
 181         ctx->key_len = cipher->key_len;
 182         /* Preserve wrap enable flag, zero everything else */
 183         ctx->flags &= EVP_CIPHER_CTX_FLAG_WRAP_ALLOW;
 184         if (ctx->cipher->flags & EVP_CIPH_CTRL_INIT) {
 185             if (!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_INIT, 0, NULL)) {
 186                 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
 187                 return 0;
 188             }
 189         }
 190     } else if (!ctx->cipher) {
 191         EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_NO_CIPHER_SET);
 192         return 0;
 193     }
 194 #ifndef OPENSSL_NO_ENGINE
 195  skip_to_init:
 196 #endif
 197     /* we assume block size is a power of 2 in *cryptUpdate */
 198     OPENSSL_assert(ctx->cipher->block_size == 1
 199                    || ctx->cipher->block_size == 8
 200                    || ctx->cipher->block_size == 16);
 201
 202     if (!(ctx->flags & EVP_CIPHER_CTX_FLAG_WRAP_ALLOW)
 203         && EVP_CIPHER_CTX_mode(ctx) == EVP_CIPH_WRAP_MODE) {
 204         EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_WRAP_MODE_NOT_ALLOWED);
 205         return 0;
 206     }
 207
 208     if (!(EVP_CIPHER_flags(EVP_CIPHER_CTX_cipher(ctx)) & EVP_CIPH_CUSTOM_IV)) {
 209         switch (EVP_CIPHER_CTX_mode(ctx)) {
 210
 211         case EVP_CIPH_STREAM_CIPHER:
 212         case EVP_CIPH_ECB_MODE:
 213             break;
 214
 215         case EVP_CIPH_CFB_MODE:
 216         case EVP_CIPH_OFB_MODE:
 217
 218             ctx->num = 0;
 219             /* fall-through */
 220
 221         case EVP_CIPH_CBC_MODE:
 222
 223             OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) <=
 224                            (int)sizeof(ctx->iv));
 225             if (iv)
 226                 memcpy(ctx->oiv, iv, EVP_CIPHER_CTX_iv_length(ctx));
 227             memcpy(ctx->iv, ctx->oiv, EVP_CIPHER_CTX_iv_length(ctx));
 228             break;
 229
 230         case EVP_CIPH_CTR_MODE:
 231             ctx->num = 0;
 232             /* Don't reuse IV for CTR mode */
 233             if (iv)
 234                 memcpy(ctx->iv, iv, EVP_CIPHER_CTX_iv_length(ctx));
 235             break;
 236
 237         default:
 238             return 0;
 239         }
 240     }
 241
 242     if (key || (ctx->cipher->flags & EVP_CIPH_ALWAYS_CALL_INIT)) {
 243         if (!ctx->cipher->init(ctx, key, iv, enc))
 244             return 0;
 245     }
 246     ctx->buf_len = 0;
 247     ctx->final_used = 0;
 248     ctx->block_mask = ctx->cipher->block_size - 1;
 249     return 1;
 250 }
 251
 252 int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
 253                      const unsigned char *in, int inl)
 254 {
 255     if (ctx->encrypt)
 256         return EVP_EncryptUpdate(ctx, out, outl, in, inl);
 257     else
 258         return EVP_DecryptUpdate(ctx, out, outl, in, inl);
 259 }
 260
 261 int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 262 {
 263     if (ctx->encrypt)
 264         return EVP_EncryptFinal_ex(ctx, out, outl);
 265     else
 266         return EVP_DecryptFinal_ex(ctx, out, outl);
 267 }
 268
 269 int EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 270 {
 271     if (ctx->encrypt)
 272         return EVP_EncryptFinal(ctx, out, outl);
 273     else
 274         return EVP_DecryptFinal(ctx, out, outl);
 275 }
 276
 277 int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
 278                     const unsigned char *key, const unsigned char *iv)
 279 {
 280     return EVP_CipherInit(ctx, cipher, key, iv, 1);
 281 }
 282
 283 int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
 284                        ENGINE *impl, const unsigned char *key,
 285                        const unsigned char *iv)
 286 {
 287     return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 1);
 288 }
 289
 290 int EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
 291                     const unsigned char *key, const unsigned char *iv)
 292 {
 293     return EVP_CipherInit(ctx, cipher, key, iv, 0);
 294 }
 295
 296 int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
 297                        ENGINE *impl, const unsigned char *key,
 298                        const unsigned char *iv)
 299 {
 300     return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 0);
 301 }
 302
 303 int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
 304                       const unsigned char *in, int inl)
 305 {
 306     int i, j, bl;
 307
 308     if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
 309         i = ctx->cipher->do_cipher(ctx, out, in, inl);
 310         if (i < 0)
 311             return 0;
 312         else
 313             *outl = i;
 314         return 1;
 315     }
 316
 317     if (inl <= 0) {
 318         *outl = 0;
 319         return inl == 0;
 320     }
 321
 322     if (ctx->buf_len == 0 && (inl & (ctx->block_mask)) == 0) {
 323         if (ctx->cipher->do_cipher(ctx, out, in, inl)) {
 324             *outl = inl;
 325             return 1;
 326         } else {
 327             *outl = 0;
 328             return 0;
 329         }
 330     }
 331     i = ctx->buf_len;
 332     bl = ctx->cipher->block_size;
 333     OPENSSL_assert(bl <= (int)sizeof(ctx->buf));
 334     if (i != 0) {
 335         if (bl - i > inl) {
 336             memcpy(&(ctx->buf[i]), in, inl);
 337             ctx->buf_len += inl;
 338             *outl = 0;
 339             return 1;
 340         } else {
 341             j = bl - i;
 342             memcpy(&(ctx->buf[i]), in, j);
 343             if (!ctx->cipher->do_cipher(ctx, out, ctx->buf, bl))
 344                 return 0;
 345             inl -= j;
 346             in += j;
 347             out += bl;
 348             *outl = bl;
 349         }
 350     } else
 351         *outl = 0;
 352     i = inl & (bl - 1);
 353     inl -= i;
 354     if (inl > 0) {
 355         if (!ctx->cipher->do_cipher(ctx, out, in, inl))
 356             return 0;
 357         *outl += inl;
 358     }
 359
 360     if (i != 0)
 361         memcpy(ctx->buf, &(in[inl]), i);
 362     ctx->buf_len = i;
 363     return 1;
 364 }
 365
 366 int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 367 {
 368     int ret;
 369     ret = EVP_EncryptFinal_ex(ctx, out, outl);
 370     return ret;
 371 }
 372
 373 int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 374 {
 375     int n, ret;
 376     unsigned int i, b, bl;
 377
 378     if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
 379         ret = ctx->cipher->do_cipher(ctx, out, NULL, 0);
 380         if (ret < 0)
 381             return 0;
 382         else
 383             *outl = ret;
 384         return 1;
 385     }
 386
 387     b = ctx->cipher->block_size;
 388     OPENSSL_assert(b <= sizeof ctx->buf);
 389     if (b == 1) {
 390         *outl = 0;
 391         return 1;
 392     }
 393     bl = ctx->buf_len;
 394     if (ctx->flags & EVP_CIPH_NO_PADDING) {
 395         if (bl) {
 396             EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX,
 397                    EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
 398             return 0;
 399         }
 400         *outl = 0;
 401         return 1;
 402     }
 403
 404     n = b - bl;
 405     for (i = bl; i < b; i++)
 406         ctx->buf[i] = n;
 407     ret = ctx->cipher->do_cipher(ctx, out, ctx->buf, b);
 408
 409     if (ret)
 410         *outl = b;
 411
 412     return ret;
 413 }
 414
 415 int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
 416                       const unsigned char *in, int inl)
 417 {
 418     int fix_len;
 419     unsigned int b;
 420
 421     if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
 422         fix_len = ctx->cipher->do_cipher(ctx, out, in, inl);
 423         if (fix_len < 0) {
 424             *outl = 0;
 425             return 0;
 426         } else
 427             *outl = fix_len;
 428         return 1;
 429     }
 430
 431     if (inl <= 0) {
 432         *outl = 0;
 433         return inl == 0;
 434     }
 435
 436     if (ctx->flags & EVP_CIPH_NO_PADDING)
 437         return EVP_EncryptUpdate(ctx, out, outl, in, inl);
 438
 439     b = ctx->cipher->block_size;
 440     OPENSSL_assert(b <= sizeof ctx->final);
 441
 442     if (ctx->final_used) {
 443         memcpy(out, ctx->final, b);
 444         out += b;
 445         fix_len = 1;
 446     } else
 447         fix_len = 0;
 448
 449     if (!EVP_EncryptUpdate(ctx, out, outl, in, inl))
 450         return 0;
 451
 452     /*
 453      * if we have 'decrypted' a multiple of block size, make sure we have a
 454      * copy of this last block
 455      */
 456     if (b > 1 && !ctx->buf_len) {
 457         *outl -= b;
 458         ctx->final_used = 1;
 459         memcpy(ctx->final, &out[*outl], b);
 460     } else
 461         ctx->final_used = 0;
 462
 463     if (fix_len)
 464         *outl += b;
 465
 466     return 1;
 467 }
 468
 469 int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 470 {
 471     int ret;
 472     ret = EVP_DecryptFinal_ex(ctx, out, outl);
 473     return ret;
 474 }
 475
 476 int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 477 {
 478     int i, n;
 479     unsigned int b;
 480     *outl = 0;
 481
 482     if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
 483         i = ctx->cipher->do_cipher(ctx, out, NULL, 0);
 484         if (i < 0)
 485             return 0;
 486         else
 487             *outl = i;
 488         return 1;
 489     }
 490
 491     b = ctx->cipher->block_size;
 492     if (ctx->flags & EVP_CIPH_NO_PADDING) {
 493         if (ctx->buf_len) {
 494             EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,
 495                    EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
 496             return 0;
 497         }
 498         *outl = 0;
 499         return 1;
 500     }
 501     if (b > 1) {
 502         if (ctx->buf_len || !ctx->final_used) {
 503             EVPerr(EVP_F_EVP_DECRYPTFINAL_EX, EVP_R_WRONG_FINAL_BLOCK_LENGTH);
 504             return (0);
 505         }
 506         OPENSSL_assert(b <= sizeof ctx->final);
 507
 508         /*
 509          * The following assumes that the ciphertext has been authenticated.
 510          * Otherwise it provides a padding oracle.
 511          */
 512         n = ctx->final[b - 1];
 513         if (n == 0 || n > (int)b) {
 514             EVPerr(EVP_F_EVP_DECRYPTFINAL_EX, EVP_R_BAD_DECRYPT);
 515             return (0);
 516         }
 517         for (i = 0; i < n; i++) {
 518             if (ctx->final[--b] != n) {
 519                 EVPerr(EVP_F_EVP_DECRYPTFINAL_EX, EVP_R_BAD_DECRYPT);
 520                 return (0);
 521             }
 522         }
 523         n = ctx->cipher->block_size - n;
 524         for (i = 0; i < n; i++)
 525             out[i] = ctx->final[i];
 526         *outl = n;
 527     } else
 528         *outl = 0;
 529     return (1);
 530 }
 531
 532 int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *c, int keylen)
 533 {
 534     if (c->cipher->flags & EVP_CIPH_CUSTOM_KEY_LENGTH)
 535         return EVP_CIPHER_CTX_ctrl(c, EVP_CTRL_SET_KEY_LENGTH, keylen, NULL);
 536     if (c->key_len == keylen)
 537         return 1;
 538     if ((keylen > 0) && (c->cipher->flags & EVP_CIPH_VARIABLE_LENGTH)) {
 539         c->key_len = keylen;
 540         return 1;
 541     }
 542     EVPerr(EVP_F_EVP_CIPHER_CTX_SET_KEY_LENGTH, EVP_R_INVALID_KEY_LENGTH);
 543     return 0;
 544 }
 545
 546 int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad)
 547 {
 548     if (pad)
 549         ctx->flags &= ~EVP_CIPH_NO_PADDING;
 550     else
 551         ctx->flags |= EVP_CIPH_NO_PADDING;
 552     return 1;
 553 }
 554
 555 int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr)
 556 {
 557     int ret;
 558     if (!ctx->cipher) {
 559         EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_NO_CIPHER_SET);
 560         return 0;
 561     }
 562
 563     if (!ctx->cipher->ctrl) {
 564         EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_NOT_IMPLEMENTED);
 565         return 0;
 566     }
 567
 568     ret = ctx->cipher->ctrl(ctx, type, arg, ptr);
 569     if (ret == -1) {
 570         EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL,
 571                EVP_R_CTRL_OPERATION_NOT_IMPLEMENTED);
 572         return 0;
 573     }
 574     return ret;
 575 }
 576
 577 int EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX *ctx, unsigned char *key)
 578 {
 579     if (ctx->cipher->flags & EVP_CIPH_RAND_KEY)
 580         return EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_RAND_KEY, 0, key);
 581     if (RAND_bytes(key, ctx->key_len) <= 0)
 582         return 0;
 583     return 1;
 584 }
 585
 586 int EVP_CIPHER_CTX_copy(EVP_CIPHER_CTX *out, const EVP_CIPHER_CTX *in)
 587 {
 588     if ((in == NULL) || (in->cipher == NULL)) {
 589         EVPerr(EVP_F_EVP_CIPHER_CTX_COPY, EVP_R_INPUT_NOT_INITIALIZED);
 590         return 0;
 591     }
 592 #ifndef OPENSSL_NO_ENGINE
 593     /* Make sure it's safe to copy a cipher context using an ENGINE */
 594     if (in->engine && !ENGINE_init(in->engine)) {
 595         EVPerr(EVP_F_EVP_CIPHER_CTX_COPY, ERR_R_ENGINE_LIB);
 596         return 0;
 597     }
 598 #endif
 599
 600     EVP_CIPHER_CTX_reset(out);
 601     memcpy(out, in, sizeof(*out));
 602
 603     if (in->cipher_data && in->cipher->ctx_size) {
 604         out->cipher_data = OPENSSL_malloc(in->cipher->ctx_size);
 605         if (out->cipher_data == NULL) {
 606             EVPerr(EVP_F_EVP_CIPHER_CTX_COPY, ERR_R_MALLOC_FAILURE);
 607             return 0;
 608         }
 609         memcpy(out->cipher_data, in->cipher_data, in->cipher->ctx_size);
 610     }
 611
 612     if (in->cipher->flags & EVP_CIPH_CUSTOM_COPY)
 613         return in->cipher->ctrl((EVP_CIPHER_CTX *)in, EVP_CTRL_COPY, 0, out);
 614     return 1;
 615 }