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 "evp_locl.h"
  71
  72 #ifdef OPENSSL_FIPS
  73 # define M_do_cipher(ctx, out, in, inl) FIPS_cipher(ctx, out, in, inl)
  74 #else
  75 # define M_do_cipher(ctx, out, in, inl) ctx->cipher->do_cipher(ctx, out, in, inl)
  76 #endif
  77
  78 const char EVP_version[] = "EVP" OPENSSL_VERSION_PTEXT;
  79
  80 void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *ctx)
  81 {
  82     memset(ctx, 0, sizeof(EVP_CIPHER_CTX));
  83     /* ctx->cipher=NULL; */
  84 }
  85
  86 EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void)
  87 {
  88     EVP_CIPHER_CTX *ctx = OPENSSL_malloc(sizeof *ctx);
  89     if (ctx)
  90         EVP_CIPHER_CTX_init(ctx);
  91     return ctx;
  92 }
  93
  94 int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
  95                    const unsigned char *key, const unsigned char *iv, int enc)
  96 {
  97     if (cipher)
  98         EVP_CIPHER_CTX_init(ctx);
  99     return EVP_CipherInit_ex(ctx, cipher, NULL, key, iv, enc);
 100 }
 101
 102 int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
 103                       ENGINE *impl, const unsigned char *key,
 104                       const unsigned char *iv, int enc)
 105 {
 106     if (enc == -1)
 107         enc = ctx->encrypt;
 108     else {
 109         if (enc)
 110             enc = 1;
 111         ctx->encrypt = enc;
 112     }
 113 #ifndef OPENSSL_NO_ENGINE
 114     /*
 115      * Whether it's nice or not, "Inits" can be used on "Final"'d contexts so
 116      * this context may already have an ENGINE! Try to avoid releasing the
 117      * previous handle, re-querying for an ENGINE, and having a
 118      * reinitialisation, when it may all be unecessary.
 119      */
 120     if (ctx->engine && ctx->cipher && (!cipher ||
 121                                        (cipher
 122                                         && (cipher->nid ==
 123                                             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_cleanup(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                  * mispellings 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 #ifdef OPENSSL_FIPS
 172         if (FIPS_mode()) {
 173             const EVP_CIPHER *fcipher;
 174             if (cipher)
 175                 fcipher = evp_get_fips_cipher(cipher);
 176             if (fcipher)
 177                 cipher = fcipher;
 178             return FIPS_cipherinit(ctx, cipher, key, iv, enc);
 179         }
 180 #endif
 181         ctx->cipher = cipher;
 182         if (ctx->cipher->ctx_size) {
 183             ctx->cipher_data = OPENSSL_malloc(ctx->cipher->ctx_size);
 184             if (!ctx->cipher_data) {
 185                 EVPerr(EVP_F_EVP_CIPHERINIT_EX, ERR_R_MALLOC_FAILURE);
 186                 return 0;
 187             }
 188         } else {
 189             ctx->cipher_data = NULL;
 190         }
 191         ctx->key_len = cipher->key_len;
 192         /* Preserve wrap enable flag, zero everything else */
 193         ctx->flags &= EVP_CIPHER_CTX_FLAG_WRAP_ALLOW;
 194         if (ctx->cipher->flags & EVP_CIPH_CTRL_INIT) {
 195             if (!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_INIT, 0, NULL)) {
 196                 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
 197                 return 0;
 198             }
 199         }
 200     } else if (!ctx->cipher) {
 201         EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_NO_CIPHER_SET);
 202         return 0;
 203     }
 204 #ifndef OPENSSL_NO_ENGINE
 205  skip_to_init:
 206 #endif
 207 #ifdef OPENSSL_FIPS
 208     if (FIPS_mode())
 209         return FIPS_cipherinit(ctx, cipher, key, iv, enc);
 210 #endif
 211     /* we assume block size is a power of 2 in *cryptUpdate */
 212     OPENSSL_assert(ctx->cipher->block_size == 1
 213                    || ctx->cipher->block_size == 8
 214                    || ctx->cipher->block_size == 16);
 215
 216     if (!(ctx->flags & EVP_CIPHER_CTX_FLAG_WRAP_ALLOW)
 217         && EVP_CIPHER_CTX_mode(ctx) == EVP_CIPH_WRAP_MODE) {
 218         EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_WRAP_MODE_NOT_ALLOWED);
 219         return 0;
 220     }
 221
 222     if (!(EVP_CIPHER_CTX_flags(ctx) & EVP_CIPH_CUSTOM_IV)) {
 223         switch (EVP_CIPHER_CTX_mode(ctx)) {
 224
 225         case EVP_CIPH_STREAM_CIPHER:
 226         case EVP_CIPH_ECB_MODE:
 227             break;
 228
 229         case EVP_CIPH_CFB_MODE:
 230         case EVP_CIPH_OFB_MODE:
 231
 232             ctx->num = 0;
 233             /* fall-through */
 234
 235         case EVP_CIPH_CBC_MODE:
 236
 237             OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) <=
 238                            (int)sizeof(ctx->iv));
 239             if (iv)
 240                 memcpy(ctx->oiv, iv, EVP_CIPHER_CTX_iv_length(ctx));
 241             memcpy(ctx->iv, ctx->oiv, EVP_CIPHER_CTX_iv_length(ctx));
 242             break;
 243
 244         case EVP_CIPH_CTR_MODE:
 245             ctx->num = 0;
 246             /* Don't reuse IV for CTR mode */
 247             if (iv)
 248                 memcpy(ctx->iv, iv, EVP_CIPHER_CTX_iv_length(ctx));
 249             break;
 250
 251         default:
 252             return 0;
 253             break;
 254         }
 255     }
 256
 257     if (key || (ctx->cipher->flags & EVP_CIPH_ALWAYS_CALL_INIT)) {
 258         if (!ctx->cipher->init(ctx, key, iv, enc))
 259             return 0;
 260     }
 261     ctx->buf_len = 0;
 262     ctx->final_used = 0;
 263     ctx->block_mask = ctx->cipher->block_size - 1;
 264     return 1;
 265 }
 266
 267 int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
 268                      const unsigned char *in, int inl)
 269 {
 270     if (ctx->encrypt)
 271         return EVP_EncryptUpdate(ctx, out, outl, in, inl);
 272     else
 273         return EVP_DecryptUpdate(ctx, out, outl, in, inl);
 274 }
 275
 276 int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 277 {
 278     if (ctx->encrypt)
 279         return EVP_EncryptFinal_ex(ctx, out, outl);
 280     else
 281         return EVP_DecryptFinal_ex(ctx, out, outl);
 282 }
 283
 284 int EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 285 {
 286     if (ctx->encrypt)
 287         return EVP_EncryptFinal(ctx, out, outl);
 288     else
 289         return EVP_DecryptFinal(ctx, out, outl);
 290 }
 291
 292 int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
 293                     const unsigned char *key, const unsigned char *iv)
 294 {
 295     return EVP_CipherInit(ctx, cipher, key, iv, 1);
 296 }
 297
 298 int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
 299                        ENGINE *impl, const unsigned char *key,
 300                        const unsigned char *iv)
 301 {
 302     return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 1);
 303 }
 304
 305 int EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
 306                     const unsigned char *key, const unsigned char *iv)
 307 {
 308     return EVP_CipherInit(ctx, cipher, key, iv, 0);
 309 }
 310
 311 int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
 312                        ENGINE *impl, const unsigned char *key,
 313                        const unsigned char *iv)
 314 {
 315     return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 0);
 316 }
 317
 318 int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
 319                       const unsigned char *in, int inl)
 320 {
 321     int i, j, bl;
 322
 323     if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
 324         i = M_do_cipher(ctx, out, in, inl);
 325         if (i < 0)
 326             return 0;
 327         else
 328             *outl = i;
 329         return 1;
 330     }
 331
 332     if (inl <= 0) {
 333         *outl = 0;
 334         return inl == 0;
 335     }
 336
 337     if (ctx->buf_len == 0 && (inl & (ctx->block_mask)) == 0) {
 338         if (M_do_cipher(ctx, out, in, inl)) {
 339             *outl = inl;
 340             return 1;
 341         } else {
 342             *outl = 0;
 343             return 0;
 344         }
 345     }
 346     i = ctx->buf_len;
 347     bl = ctx->cipher->block_size;
 348     OPENSSL_assert(bl <= (int)sizeof(ctx->buf));
 349     if (i != 0) {
 350         if (i + inl < bl) {
 351             memcpy(&(ctx->buf[i]), in, inl);
 352             ctx->buf_len += inl;
 353             *outl = 0;
 354             return 1;
 355         } else {
 356             j = bl - i;
 357             memcpy(&(ctx->buf[i]), in, j);
 358             if (!M_do_cipher(ctx, out, ctx->buf, bl))
 359                 return 0;
 360             inl -= j;
 361             in += j;
 362             out += bl;
 363             *outl = bl;
 364         }
 365     } else
 366         *outl = 0;
 367     i = inl & (bl - 1);
 368     inl -= i;
 369     if (inl > 0) {
 370         if (!M_do_cipher(ctx, out, in, inl))
 371             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         ret = M_do_cipher(ctx, out, NULL, 0);
 395         if (ret < 0)
 396             return 0;
 397         else
 398             *outl = ret;
 399         return 1;
 400     }
 401
 402     b = ctx->cipher->block_size;
 403     OPENSSL_assert(b <= sizeof ctx->buf);
 404     if (b == 1) {
 405         *outl = 0;
 406         return 1;
 407     }
 408     bl = ctx->buf_len;
 409     if (ctx->flags & EVP_CIPH_NO_PADDING) {
 410         if (bl) {
 411             EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX,
 412                    EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
 413             return 0;
 414         }
 415         *outl = 0;
 416         return 1;
 417     }
 418
 419     n = b - bl;
 420     for (i = bl; i < b; i++)
 421         ctx->buf[i] = n;
 422     ret = M_do_cipher(ctx, out, ctx->buf, b);
 423
 424     if (ret)
 425         *outl = b;
 426
 427     return ret;
 428 }
 429
 430 int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
 431                       const unsigned char *in, int inl)
 432 {
 433     int fix_len;
 434     unsigned int b;
 435
 436     if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
 437         fix_len = M_do_cipher(ctx, out, in, inl);
 438         if (fix_len < 0) {
 439             *outl = 0;
 440             return 0;
 441         } else
 442             *outl = fix_len;
 443         return 1;
 444     }
 445
 446     if (inl <= 0) {
 447         *outl = 0;
 448         return inl == 0;
 449     }
 450
 451     if (ctx->flags & EVP_CIPH_NO_PADDING)
 452         return EVP_EncryptUpdate(ctx, out, outl, in, inl);
 453
 454     b = ctx->cipher->block_size;
 455     OPENSSL_assert(b <= sizeof ctx->final);
 456
 457     if (ctx->final_used) {
 458         memcpy(out, ctx->final, b);
 459         out += b;
 460         fix_len = 1;
 461     } else
 462         fix_len = 0;
 463
 464     if (!EVP_EncryptUpdate(ctx, out, outl, in, inl))
 465         return 0;
 466
 467     /*
 468      * if we have 'decrypted' a multiple of block size, make sure we have a
 469      * copy of this last block
 470      */
 471     if (b > 1 && !ctx->buf_len) {
 472         *outl -= b;
 473         ctx->final_used = 1;
 474         memcpy(ctx->final, &out[*outl], b);
 475     } else
 476         ctx->final_used = 0;
 477
 478     if (fix_len)
 479         *outl += b;
 480
 481     return 1;
 482 }
 483
 484 int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 485 {
 486     int ret;
 487     ret = EVP_DecryptFinal_ex(ctx, out, outl);
 488     return ret;
 489 }
 490
 491 int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
 492 {
 493     int i, n;
 494     unsigned int b;
 495     *outl = 0;
 496
 497     if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
 498         i = M_do_cipher(ctx, out, NULL, 0);
 499         if (i < 0)
 500             return 0;
 501         else
 502             *outl = i;
 503         return 1;
 504     }
 505
 506     b = ctx->cipher->block_size;
 507     if (ctx->flags & EVP_CIPH_NO_PADDING) {
 508         if (ctx->buf_len) {
 509             EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,
 510                    EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
 511             return 0;
 512         }
 513         *outl = 0;
 514         return 1;
 515     }
 516     if (b > 1) {
 517         if (ctx->buf_len || !ctx->final_used) {
 518             EVPerr(EVP_F_EVP_DECRYPTFINAL_EX, EVP_R_WRONG_FINAL_BLOCK_LENGTH);
 519             return (0);
 520         }
 521         OPENSSL_assert(b <= sizeof ctx->final);
 522
 523         /*
 524          * The following assumes that the ciphertext has been authenticated.
 525          * Otherwise it provides a padding oracle.
 526          */
 527         n = ctx->final[b - 1];
 528         if (n == 0 || n > (int)b) {
 529             EVPerr(EVP_F_EVP_DECRYPTFINAL_EX, EVP_R_BAD_DECRYPT);
 530             return (0);
 531         }
 532         for (i = 0; i < n; i++) {
 533             if (ctx->final[--b] != n) {
 534                 EVPerr(EVP_F_EVP_DECRYPTFINAL_EX, EVP_R_BAD_DECRYPT);
 535                 return (0);
 536             }
 537         }
 538         n = ctx->cipher->block_size - n;
 539         for (i = 0; i < n; i++)
 540             out[i] = ctx->final[i];
 541         *outl = n;
 542     } else
 543         *outl = 0;
 544     return (1);
 545 }
 546
 547 void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx)
 548 {
 549     if (ctx) {
 550         EVP_CIPHER_CTX_cleanup(ctx);
 551         OPENSSL_free(ctx);
 552     }
 553 }
 554
 555 int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *c)
 556 {
 557 #ifndef OPENSSL_FIPS
 558     if (c->cipher != NULL) {
 559         if (c->cipher->cleanup && !c->cipher->cleanup(c))
 560             return 0;
 561         /* Cleanse cipher context data */
 562         if (c->cipher_data)
 563             OPENSSL_cleanse(c->cipher_data, c->cipher->ctx_size);
 564     }
 565     if (c->cipher_data)
 566         OPENSSL_free(c->cipher_data);
 567 #endif
 568 #ifndef OPENSSL_NO_ENGINE
 569     if (c->engine)
 570         /*
 571          * The EVP_CIPHER we used belongs to an ENGINE, release the
 572          * functional reference we held for this reason.
 573          */
 574         ENGINE_finish(c->engine);
 575 #endif
 576 #ifdef OPENSSL_FIPS
 577     FIPS_cipher_ctx_cleanup(c);
 578 #endif
 579     memset(c, 0, sizeof(EVP_CIPHER_CTX));
 580     return 1;
 581 }
 582
 583 int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *c, int keylen)
 584 {
 585     if (c->cipher->flags & EVP_CIPH_CUSTOM_KEY_LENGTH)
 586         return EVP_CIPHER_CTX_ctrl(c, EVP_CTRL_SET_KEY_LENGTH, keylen, NULL);
 587     if (c->key_len == keylen)
 588         return 1;
 589     if ((keylen > 0) && (c->cipher->flags & EVP_CIPH_VARIABLE_LENGTH)) {
 590         c->key_len = keylen;
 591         return 1;
 592     }
 593     EVPerr(EVP_F_EVP_CIPHER_CTX_SET_KEY_LENGTH, EVP_R_INVALID_KEY_LENGTH);
 594     return 0;
 595 }
 596
 597 int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad)
 598 {
 599     if (pad)
 600         ctx->flags &= ~EVP_CIPH_NO_PADDING;
 601     else
 602         ctx->flags |= EVP_CIPH_NO_PADDING;
 603     return 1;
 604 }
 605
 606 int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr)
 607 {
 608     int ret;
 609     if (!ctx->cipher) {
 610         EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_NO_CIPHER_SET);
 611         return 0;
 612     }
 613
 614     if (!ctx->cipher->ctrl) {
 615         EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_NOT_IMPLEMENTED);
 616         return 0;
 617     }
 618
 619     ret = ctx->cipher->ctrl(ctx, type, arg, ptr);
 620     if (ret == -1) {
 621         EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL,
 622                EVP_R_CTRL_OPERATION_NOT_IMPLEMENTED);
 623         return 0;
 624     }
 625     return ret;
 626 }
 627
 628 int EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX *ctx, unsigned char *key)
 629 {
 630     if (ctx->cipher->flags & EVP_CIPH_RAND_KEY)
 631         return EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_RAND_KEY, 0, key);
 632     if (RAND_bytes(key, ctx->key_len) <= 0)
 633         return 0;
 634     return 1;
 635 }
 636
 637 int EVP_CIPHER_CTX_copy(EVP_CIPHER_CTX *out, const EVP_CIPHER_CTX *in)
 638 {
 639     if ((in == NULL) || (in->cipher == NULL)) {
 640         EVPerr(EVP_F_EVP_CIPHER_CTX_COPY, EVP_R_INPUT_NOT_INITIALIZED);
 641         return 0;
 642     }
 643 #ifndef OPENSSL_NO_ENGINE
 644     /* Make sure it's safe to copy a cipher context using an ENGINE */
 645     if (in->engine && !ENGINE_init(in->engine)) {
 646         EVPerr(EVP_F_EVP_CIPHER_CTX_COPY, ERR_R_ENGINE_LIB);
 647         return 0;
 648     }
 649 #endif
 650
 651     EVP_CIPHER_CTX_cleanup(out);
 652     memcpy(out, in, sizeof *out);
 653
 654     if (in->cipher_data && in->cipher->ctx_size) {
 655         out->cipher_data = OPENSSL_malloc(in->cipher->ctx_size);
 656         if (!out->cipher_data) {
 657             EVPerr(EVP_F_EVP_CIPHER_CTX_COPY, ERR_R_MALLOC_FAILURE);
 658             return 0;
 659         }
 660         memcpy(out->cipher_data, in->cipher_data, in->cipher->ctx_size);
 661     }
 662
 663     if (in->cipher->flags & EVP_CIPH_CUSTOM_COPY)
 664         return in->cipher->ctrl((EVP_CIPHER_CTX *)in, EVP_CTRL_COPY, 0, out);
 665     return 1;
 666 }