Home | History | Annotate | Download | only in cipher
      1 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com)
      2  * All rights reserved.
      3  *
      4  * This package is an SSL implementation written
      5  * by Eric Young (eay (at) 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 (at) 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 (at) 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 (at) 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 #include <openssl/cipher.h>
     58 
     59 #include <assert.h>
     60 #include <string.h>
     61 
     62 #include <openssl/err.h>
     63 #include <openssl/mem.h>
     64 #include <openssl/nid.h>
     65 
     66 #include "internal.h"
     67 #include "../../internal.h"
     68 
     69 
     70 void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *ctx) {
     71   OPENSSL_memset(ctx, 0, sizeof(EVP_CIPHER_CTX));
     72 }
     73 
     74 EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void) {
     75   EVP_CIPHER_CTX *ctx = OPENSSL_malloc(sizeof(EVP_CIPHER_CTX));
     76   if (ctx) {
     77     EVP_CIPHER_CTX_init(ctx);
     78   }
     79   return ctx;
     80 }
     81 
     82 int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *c) {
     83   if (c->cipher != NULL) {
     84     if (c->cipher->cleanup) {
     85       c->cipher->cleanup(c);
     86     }
     87     OPENSSL_cleanse(c->cipher_data, c->cipher->ctx_size);
     88   }
     89   OPENSSL_free(c->cipher_data);
     90 
     91   OPENSSL_memset(c, 0, sizeof(EVP_CIPHER_CTX));
     92   return 1;
     93 }
     94 
     95 void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx) {
     96   if (ctx) {
     97     EVP_CIPHER_CTX_cleanup(ctx);
     98     OPENSSL_free(ctx);
     99   }
    100 }
    101 
    102 int EVP_CIPHER_CTX_copy(EVP_CIPHER_CTX *out, const EVP_CIPHER_CTX *in) {
    103   if (in == NULL || in->cipher == NULL) {
    104     OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_INPUT_NOT_INITIALIZED);
    105     return 0;
    106   }
    107 
    108   EVP_CIPHER_CTX_cleanup(out);
    109   OPENSSL_memcpy(out, in, sizeof(EVP_CIPHER_CTX));
    110 
    111   if (in->cipher_data && in->cipher->ctx_size) {
    112     out->cipher_data = OPENSSL_malloc(in->cipher->ctx_size);
    113     if (!out->cipher_data) {
    114       out->cipher = NULL;
    115       OPENSSL_PUT_ERROR(CIPHER, ERR_R_MALLOC_FAILURE);
    116       return 0;
    117     }
    118     OPENSSL_memcpy(out->cipher_data, in->cipher_data, in->cipher->ctx_size);
    119   }
    120 
    121   if (in->cipher->flags & EVP_CIPH_CUSTOM_COPY) {
    122     if (!in->cipher->ctrl((EVP_CIPHER_CTX *)in, EVP_CTRL_COPY, 0, out)) {
    123       out->cipher = NULL;
    124       return 0;
    125     }
    126   }
    127 
    128   return 1;
    129 }
    130 
    131 int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
    132                       ENGINE *engine, const uint8_t *key, const uint8_t *iv,
    133                       int enc) {
    134   if (enc == -1) {
    135     enc = ctx->encrypt;
    136   } else {
    137     if (enc) {
    138       enc = 1;
    139     }
    140     ctx->encrypt = enc;
    141   }
    142 
    143   if (cipher) {
    144     /* Ensure a context left from last time is cleared (the previous check
    145      * attempted to avoid this if the same ENGINE and EVP_CIPHER could be
    146      * used). */
    147     if (ctx->cipher) {
    148       EVP_CIPHER_CTX_cleanup(ctx);
    149       /* Restore encrypt and flags */
    150       ctx->encrypt = enc;
    151     }
    152 
    153     ctx->cipher = cipher;
    154     if (ctx->cipher->ctx_size) {
    155       ctx->cipher_data = OPENSSL_malloc(ctx->cipher->ctx_size);
    156       if (!ctx->cipher_data) {
    157         ctx->cipher = NULL;
    158         OPENSSL_PUT_ERROR(CIPHER, ERR_R_MALLOC_FAILURE);
    159         return 0;
    160       }
    161     } else {
    162       ctx->cipher_data = NULL;
    163     }
    164 
    165     ctx->key_len = cipher->key_len;
    166     ctx->flags = 0;
    167 
    168     if (ctx->cipher->flags & EVP_CIPH_CTRL_INIT) {
    169       if (!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_INIT, 0, NULL)) {
    170         ctx->cipher = NULL;
    171         OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_INITIALIZATION_ERROR);
    172         return 0;
    173       }
    174     }
    175   } else if (!ctx->cipher) {
    176     OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_NO_CIPHER_SET);
    177     return 0;
    178   }
    179 
    180   /* we assume block size is a power of 2 in *cryptUpdate */
    181   assert(ctx->cipher->block_size == 1 || ctx->cipher->block_size == 8 ||
    182          ctx->cipher->block_size == 16);
    183 
    184   if (!(EVP_CIPHER_CTX_flags(ctx) & EVP_CIPH_CUSTOM_IV)) {
    185     switch (EVP_CIPHER_CTX_mode(ctx)) {
    186       case EVP_CIPH_STREAM_CIPHER:
    187       case EVP_CIPH_ECB_MODE:
    188         break;
    189 
    190       case EVP_CIPH_CFB_MODE:
    191         ctx->num = 0;
    192         /* fall-through */
    193 
    194       case EVP_CIPH_CBC_MODE:
    195         assert(EVP_CIPHER_CTX_iv_length(ctx) <= sizeof(ctx->iv));
    196         if (iv) {
    197           OPENSSL_memcpy(ctx->oiv, iv, EVP_CIPHER_CTX_iv_length(ctx));
    198         }
    199         OPENSSL_memcpy(ctx->iv, ctx->oiv, EVP_CIPHER_CTX_iv_length(ctx));
    200         break;
    201 
    202       case EVP_CIPH_CTR_MODE:
    203       case EVP_CIPH_OFB_MODE:
    204         ctx->num = 0;
    205         /* Don't reuse IV for CTR mode */
    206         if (iv) {
    207           OPENSSL_memcpy(ctx->iv, iv, EVP_CIPHER_CTX_iv_length(ctx));
    208         }
    209         break;
    210 
    211       default:
    212         return 0;
    213     }
    214   }
    215 
    216   if (key || (ctx->cipher->flags & EVP_CIPH_ALWAYS_CALL_INIT)) {
    217     if (!ctx->cipher->init(ctx, key, iv, enc)) {
    218       return 0;
    219     }
    220   }
    221 
    222   ctx->buf_len = 0;
    223   ctx->final_used = 0;
    224   ctx->block_mask = ctx->cipher->block_size - 1;
    225   return 1;
    226 }
    227 
    228 int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
    229                        ENGINE *impl, const uint8_t *key, const uint8_t *iv) {
    230   return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 1);
    231 }
    232 
    233 int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
    234                        ENGINE *impl, const uint8_t *key, const uint8_t *iv) {
    235   return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 0);
    236 }
    237 
    238 int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, uint8_t *out, int *out_len,
    239                       const uint8_t *in, int in_len) {
    240   int i, j, bl;
    241 
    242   if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
    243     i = ctx->cipher->cipher(ctx, out, in, in_len);
    244     if (i < 0) {
    245       return 0;
    246     } else {
    247       *out_len = i;
    248     }
    249     return 1;
    250   }
    251 
    252   if (in_len <= 0) {
    253     *out_len = 0;
    254     return in_len == 0;
    255   }
    256 
    257   if (ctx->buf_len == 0 && (in_len & ctx->block_mask) == 0) {
    258     if (ctx->cipher->cipher(ctx, out, in, in_len)) {
    259       *out_len = in_len;
    260       return 1;
    261     } else {
    262       *out_len = 0;
    263       return 0;
    264     }
    265   }
    266 
    267   i = ctx->buf_len;
    268   bl = ctx->cipher->block_size;
    269   assert(bl <= (int)sizeof(ctx->buf));
    270   if (i != 0) {
    271     if (bl - i > in_len) {
    272       OPENSSL_memcpy(&ctx->buf[i], in, in_len);
    273       ctx->buf_len += in_len;
    274       *out_len = 0;
    275       return 1;
    276     } else {
    277       j = bl - i;
    278       OPENSSL_memcpy(&ctx->buf[i], in, j);
    279       if (!ctx->cipher->cipher(ctx, out, ctx->buf, bl)) {
    280         return 0;
    281       }
    282       in_len -= j;
    283       in += j;
    284       out += bl;
    285       *out_len = bl;
    286     }
    287   } else {
    288     *out_len = 0;
    289   }
    290 
    291   i = in_len & ctx->block_mask;
    292   in_len -= i;
    293   if (in_len > 0) {
    294     if (!ctx->cipher->cipher(ctx, out, in, in_len)) {
    295       return 0;
    296     }
    297     *out_len += in_len;
    298   }
    299 
    300   if (i != 0) {
    301     OPENSSL_memcpy(ctx->buf, &in[in_len], i);
    302   }
    303   ctx->buf_len = i;
    304   return 1;
    305 }
    306 
    307 int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, uint8_t *out, int *out_len) {
    308   int n, ret;
    309   unsigned int i, b, bl;
    310 
    311   if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
    312     ret = ctx->cipher->cipher(ctx, out, NULL, 0);
    313     if (ret < 0) {
    314       return 0;
    315     } else {
    316       *out_len = ret;
    317     }
    318     return 1;
    319   }
    320 
    321   b = ctx->cipher->block_size;
    322   assert(b <= sizeof(ctx->buf));
    323   if (b == 1) {
    324     *out_len = 0;
    325     return 1;
    326   }
    327 
    328   bl = ctx->buf_len;
    329   if (ctx->flags & EVP_CIPH_NO_PADDING) {
    330     if (bl) {
    331       OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
    332       return 0;
    333     }
    334     *out_len = 0;
    335     return 1;
    336   }
    337 
    338   n = b - bl;
    339   for (i = bl; i < b; i++) {
    340     ctx->buf[i] = n;
    341   }
    342   ret = ctx->cipher->cipher(ctx, out, ctx->buf, b);
    343 
    344   if (ret) {
    345     *out_len = b;
    346   }
    347 
    348   return ret;
    349 }
    350 
    351 int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, uint8_t *out, int *out_len,
    352                       const uint8_t *in, int in_len) {
    353   int fix_len;
    354   unsigned int b;
    355 
    356   if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
    357     int r = ctx->cipher->cipher(ctx, out, in, in_len);
    358     if (r < 0) {
    359       *out_len = 0;
    360       return 0;
    361     } else {
    362       *out_len = r;
    363     }
    364     return 1;
    365   }
    366 
    367   if (in_len <= 0) {
    368     *out_len = 0;
    369     return in_len == 0;
    370   }
    371 
    372   if (ctx->flags & EVP_CIPH_NO_PADDING) {
    373     return EVP_EncryptUpdate(ctx, out, out_len, in, in_len);
    374   }
    375 
    376   b = ctx->cipher->block_size;
    377   assert(b <= sizeof(ctx->final));
    378 
    379   if (ctx->final_used) {
    380     OPENSSL_memcpy(out, ctx->final, b);
    381     out += b;
    382     fix_len = 1;
    383   } else {
    384     fix_len = 0;
    385   }
    386 
    387   if (!EVP_EncryptUpdate(ctx, out, out_len, in, in_len)) {
    388     return 0;
    389   }
    390 
    391   /* if we have 'decrypted' a multiple of block size, make sure
    392    * we have a copy of this last block */
    393   if (b > 1 && !ctx->buf_len) {
    394     *out_len -= b;
    395     ctx->final_used = 1;
    396     OPENSSL_memcpy(ctx->final, &out[*out_len], b);
    397   } else {
    398     ctx->final_used = 0;
    399   }
    400 
    401   if (fix_len) {
    402     *out_len += b;
    403   }
    404 
    405   return 1;
    406 }
    407 
    408 int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *out_len) {
    409   int i, n;
    410   unsigned int b;
    411   *out_len = 0;
    412 
    413   if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
    414     i = ctx->cipher->cipher(ctx, out, NULL, 0);
    415     if (i < 0) {
    416       return 0;
    417     } else {
    418       *out_len = i;
    419     }
    420     return 1;
    421   }
    422 
    423   b = ctx->cipher->block_size;
    424   if (ctx->flags & EVP_CIPH_NO_PADDING) {
    425     if (ctx->buf_len) {
    426       OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
    427       return 0;
    428     }
    429     *out_len = 0;
    430     return 1;
    431   }
    432 
    433   if (b > 1) {
    434     if (ctx->buf_len || !ctx->final_used) {
    435       OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_WRONG_FINAL_BLOCK_LENGTH);
    436       return 0;
    437     }
    438     assert(b <= sizeof(ctx->final));
    439 
    440     /* The following assumes that the ciphertext has been authenticated.
    441      * Otherwise it provides a padding oracle. */
    442     n = ctx->final[b - 1];
    443     if (n == 0 || n > (int)b) {
    444       OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_BAD_DECRYPT);
    445       return 0;
    446     }
    447 
    448     for (i = 0; i < n; i++) {
    449       if (ctx->final[--b] != n) {
    450         OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_BAD_DECRYPT);
    451         return 0;
    452       }
    453     }
    454 
    455     n = ctx->cipher->block_size - n;
    456     for (i = 0; i < n; i++) {
    457       out[i] = ctx->final[i];
    458     }
    459     *out_len = n;
    460   } else {
    461     *out_len = 0;
    462   }
    463 
    464   return 1;
    465 }
    466 
    467 int EVP_Cipher(EVP_CIPHER_CTX *ctx, uint8_t *out, const uint8_t *in,
    468                size_t in_len) {
    469   return ctx->cipher->cipher(ctx, out, in, in_len);
    470 }
    471 
    472 int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, uint8_t *out, int *out_len,
    473                      const uint8_t *in, int in_len) {
    474   if (ctx->encrypt) {
    475     return EVP_EncryptUpdate(ctx, out, out_len, in, in_len);
    476   } else {
    477     return EVP_DecryptUpdate(ctx, out, out_len, in, in_len);
    478   }
    479 }
    480 
    481 int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, uint8_t *out, int *out_len) {
    482   if (ctx->encrypt) {
    483     return EVP_EncryptFinal_ex(ctx, out, out_len);
    484   } else {
    485     return EVP_DecryptFinal_ex(ctx, out, out_len);
    486   }
    487 }
    488 
    489 const EVP_CIPHER *EVP_CIPHER_CTX_cipher(const EVP_CIPHER_CTX *ctx) {
    490   return ctx->cipher;
    491 }
    492 
    493 int EVP_CIPHER_CTX_nid(const EVP_CIPHER_CTX *ctx) {
    494   return ctx->cipher->nid;
    495 }
    496 
    497 unsigned EVP_CIPHER_CTX_block_size(const EVP_CIPHER_CTX *ctx) {
    498   return ctx->cipher->block_size;
    499 }
    500 
    501 unsigned EVP_CIPHER_CTX_key_length(const EVP_CIPHER_CTX *ctx) {
    502   return ctx->key_len;
    503 }
    504 
    505 unsigned EVP_CIPHER_CTX_iv_length(const EVP_CIPHER_CTX *ctx) {
    506   return ctx->cipher->iv_len;
    507 }
    508 
    509 void *EVP_CIPHER_CTX_get_app_data(const EVP_CIPHER_CTX *ctx) {
    510   return ctx->app_data;
    511 }
    512 
    513 void EVP_CIPHER_CTX_set_app_data(EVP_CIPHER_CTX *ctx, void *data) {
    514   ctx->app_data = data;
    515 }
    516 
    517 uint32_t EVP_CIPHER_CTX_flags(const EVP_CIPHER_CTX *ctx) {
    518   return ctx->cipher->flags & ~EVP_CIPH_MODE_MASK;
    519 }
    520 
    521 uint32_t EVP_CIPHER_CTX_mode(const EVP_CIPHER_CTX *ctx) {
    522   return ctx->cipher->flags & EVP_CIPH_MODE_MASK;
    523 }
    524 
    525 int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int command, int arg, void *ptr) {
    526   int ret;
    527   if (!ctx->cipher) {
    528     OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_NO_CIPHER_SET);
    529     return 0;
    530   }
    531 
    532   if (!ctx->cipher->ctrl) {
    533     OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_CTRL_NOT_IMPLEMENTED);
    534     return 0;
    535   }
    536 
    537   ret = ctx->cipher->ctrl(ctx, command, arg, ptr);
    538   if (ret == -1) {
    539     OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_CTRL_OPERATION_NOT_IMPLEMENTED);
    540     return 0;
    541   }
    542 
    543   return ret;
    544 }
    545 
    546 int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad) {
    547   if (pad) {
    548     ctx->flags &= ~EVP_CIPH_NO_PADDING;
    549   } else {
    550     ctx->flags |= EVP_CIPH_NO_PADDING;
    551   }
    552   return 1;
    553 }
    554 
    555 int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *c, unsigned key_len) {
    556   if (c->key_len == key_len) {
    557     return 1;
    558   }
    559 
    560   if (key_len == 0 || !(c->cipher->flags & EVP_CIPH_VARIABLE_LENGTH)) {
    561     OPENSSL_PUT_ERROR(CIPHER, CIPHER_R_INVALID_KEY_LENGTH);
    562     return 0;
    563   }
    564 
    565   c->key_len = key_len;
    566   return 1;
    567 }
    568 
    569 int EVP_CIPHER_nid(const EVP_CIPHER *cipher) { return cipher->nid; }
    570 
    571 unsigned EVP_CIPHER_block_size(const EVP_CIPHER *cipher) {
    572   return cipher->block_size;
    573 }
    574 
    575 unsigned EVP_CIPHER_key_length(const EVP_CIPHER *cipher) {
    576   return cipher->key_len;
    577 }
    578 
    579 unsigned EVP_CIPHER_iv_length(const EVP_CIPHER *cipher) {
    580   return cipher->iv_len;
    581 }
    582 
    583 uint32_t EVP_CIPHER_flags(const EVP_CIPHER *cipher) {
    584   return cipher->flags & ~EVP_CIPH_MODE_MASK;
    585 }
    586 
    587 uint32_t EVP_CIPHER_mode(const EVP_CIPHER *cipher) {
    588   return cipher->flags & EVP_CIPH_MODE_MASK;
    589 }
    590 
    591 int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
    592                    const uint8_t *key, const uint8_t *iv, int enc) {
    593   if (cipher) {
    594     EVP_CIPHER_CTX_init(ctx);
    595   }
    596   return EVP_CipherInit_ex(ctx, cipher, NULL, key, iv, enc);
    597 }
    598 
    599 int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
    600                     const uint8_t *key, const uint8_t *iv) {
    601   return EVP_CipherInit(ctx, cipher, key, iv, 1);
    602 }
    603 
    604 int EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
    605                     const uint8_t *key, const uint8_t *iv) {
    606   return EVP_CipherInit(ctx, cipher, key, iv, 0);
    607 }
    608 
    609 int EVP_add_cipher_alias(const char *a, const char *b) {
    610   return 1;
    611 }
    612