1 /*

     2  * Blowfish algorithm

     3  *

     4  * This file is part of Libav.

     5  *

     6  * Libav is free software; you can redistribute it and/or

     7  * modify it under the terms of the GNU Lesser General Public

     8  * License as published by the Free Software Foundation; either

     9  * version 2.1 of the License, or (at your option) any later version.

    10  *

    11  * Libav is distributed in the hope that it will be useful,

    12  * but WITHOUT ANY WARRANTY; without even the implied warranty of

    13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

    14  * Lesser General Public License for more details.

    15  *

    16  * You should have received a copy of the GNU Lesser General Public

    17  * License along with Libav; if not, write to the Free Software

    18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

    19  */

    20 

    21 #ifndef AVUTIL_BLOWFISH_H

    22 #define AVUTIL_BLOWFISH_H

    23 

    24 #include <stdint.h>

    25 

    26 /**

    27  * @defgroup lavu_blowfish Blowfish

    28  * @ingroup lavu_crypto

    29  * @{

    30  */

    31 

    32 #define AV_BF_ROUNDS 16

    33 

    34 typedef struct AVBlowfish {

    35     uint32_t p[AV_BF_ROUNDS + 2];

    36     uint32_t s[4][256];

    37 } AVBlowfish;

    38 

    39 /**

    40  * Initialize an AVBlowfish context.

    41  *

    42  * @param ctx an AVBlowfish context

    43  * @param key a key

    44  * @param key_len length of the key

    45  */

    46 void av_blowfish_init(struct AVBlowfish *ctx, const uint8_t *key, int key_len);

    47 

    48 /**

    49  * Encrypt or decrypt a buffer using a previously initialized context.

    50  *

    51  * @param ctx an AVBlowfish context

    52  * @param xl left four bytes halves of input to be encrypted

    53  * @param xr right four bytes halves of input to be encrypted

    54  * @param decrypt 0 for encryption, 1 for decryption

    55  */

    56 void av_blowfish_crypt_ecb(struct AVBlowfish *ctx, uint32_t *xl, uint32_t *xr,

    57                            int decrypt);

    58 

    59 /**

    60  * Encrypt or decrypt a buffer using a previously initialized context.

    61  *

    62  * @param ctx an AVBlowfish context

    63  * @param dst destination array, can be equal to src

    64  * @param src source array, can be equal to dst

    65  * @param count number of 8 byte blocks

    66  * @param iv initialization vector for CBC mode, if NULL ECB will be used

    67  * @param decrypt 0 for encryption, 1 for decryption

    68  */

    69 void av_blowfish_crypt(struct AVBlowfish *ctx, uint8_t *dst, const uint8_t *src,

    70                        int count, uint8_t *iv, int decrypt);

    71 

    72 /**

    73  * @}

    74  */

    75 

    76 #endif /* AVUTIL_BLOWFISH_H */