1 /* 2 * DES encryption/decryption 3 * Copyright (c) 2007 Reimar Doeffinger 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_DES_H 23 #define AVUTIL_DES_H 24 25 #include <stdint.h> 26 27 /** 28 * @defgroup lavu_des DES 29 * @ingroup lavu_crypto 30 * @{ 31 */ 32 33 typedef struct AVDES { 34 uint64_t round_keys[3][16]; 35 int triple_des; 36 } AVDES; 37 38 /** 39 * Allocate an AVDES context. 40 */ 41 AVDES *av_des_alloc(void); 42 43 /** 44 * @brief Initializes an AVDES context. 45 * 46 * @param key_bits must be 64 or 192 47 * @param decrypt 0 for encryption/CBC-MAC, 1 for decryption 48 * @return zero on success, negative value otherwise 49 */ 50 int av_des_init(struct AVDES *d, const uint8_t *key, int key_bits, int decrypt); 51 52 /** 53 * @brief Encrypts / decrypts using the DES algorithm. 54 * 55 * @param count number of 8 byte blocks 56 * @param dst destination array, can be equal to src, must be 8-byte aligned 57 * @param src source array, can be equal to dst, must be 8-byte aligned, may be NULL 58 * @param iv initialization vector for CBC mode, if NULL then ECB will be used, 59 * must be 8-byte aligned 60 * @param decrypt 0 for encryption, 1 for decryption 61 */ 62 void av_des_crypt(struct AVDES *d, uint8_t *dst, const uint8_t *src, int count, uint8_t *iv, int decrypt); 63 64 /** 65 * @brief Calculates CBC-MAC using the DES algorithm. 66 * 67 * @param count number of 8 byte blocks 68 * @param dst destination array, can be equal to src, must be 8-byte aligned 69 * @param src source array, can be equal to dst, must be 8-byte aligned, may be NULL 70 */ 71 void av_des_mac(struct AVDES *d, uint8_t *dst, const uint8_t *src, int count); 72 73 /** 74 * @} 75 */ 76 77 #endif /* AVUTIL_DES_H */ 78