1 /* 2 * Blowfish algorithm 3 * Copyright (c) 2012 Samuel Pitoiset 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22 #ifndef AVUTIL_BLOWFISH_H 23 #define AVUTIL_BLOWFISH_H 24 25 #include <stdint.h> 26 27 /** 28 * @defgroup lavu_blowfish Blowfish 29 * @ingroup lavu_crypto 30 * @{ 31 */ 32 33 #define AV_BF_ROUNDS 16 34 35 typedef struct AVBlowfish { 36 uint32_t p[AV_BF_ROUNDS + 2]; 37 uint32_t s[4][256]; 38 } AVBlowfish; 39 40 /** 41 * Allocate an AVBlowfish context. 42 */ 43 AVBlowfish *av_blowfish_alloc(void); 44 45 /** 46 * Initialize an AVBlowfish context. 47 * 48 * @param ctx an AVBlowfish context 49 * @param key a key 50 * @param key_len length of the key 51 */ 52 void av_blowfish_init(struct AVBlowfish *ctx, const uint8_t *key, int key_len); 53 54 /** 55 * Encrypt or decrypt a buffer using a previously initialized context. 56 * 57 * @param ctx an AVBlowfish context 58 * @param xl left four bytes halves of input to be encrypted 59 * @param xr right four bytes halves of input to be encrypted 60 * @param decrypt 0 for encryption, 1 for decryption 61 */ 62 void av_blowfish_crypt_ecb(struct AVBlowfish *ctx, uint32_t *xl, uint32_t *xr, 63 int decrypt); 64 65 /** 66 * Encrypt or decrypt a buffer using a previously initialized context. 67 * 68 * @param ctx an AVBlowfish context 69 * @param dst destination array, can be equal to src 70 * @param src source array, can be equal to dst 71 * @param count number of 8 byte blocks 72 * @param iv initialization vector for CBC mode, if NULL ECB will be used 73 * @param decrypt 0 for encryption, 1 for decryption 74 */ 75 void av_blowfish_crypt(struct AVBlowfish *ctx, uint8_t *dst, const uint8_t *src, 76 int count, uint8_t *iv, int decrypt); 77 78 /** 79 * @} 80 */ 81 82 #endif /* AVUTIL_BLOWFISH_H */ 83