tea.h (2035B)
1 /* 2 * A 32-bit implementation of the TEA algorithm 3 * Copyright (c) 2015 Vesselin Bontchev 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_TEA_H 23 #define AVUTIL_TEA_H 24 25 #include <stdint.h> 26 27 /** 28 * @file 29 * @brief Public header for libavutil TEA algorithm 30 * @defgroup lavu_tea TEA 31 * @ingroup lavu_crypto 32 * @{ 33 */ 34 35 extern const int av_tea_size; 36 37 struct AVTEA; 38 39 /** 40 * Allocate an AVTEA context 41 * To free the struct: av_free(ptr) 42 */ 43 struct AVTEA *av_tea_alloc(void); 44 45 /** 46 * Initialize an AVTEA context. 47 * 48 * @param ctx an AVTEA context 49 * @param key a key of 16 bytes used for encryption/decryption 50 * @param rounds the number of rounds in TEA (64 is the "standard") 51 */ 52 void av_tea_init(struct AVTEA *ctx, const uint8_t key[16], int rounds); 53 54 /** 55 * Encrypt or decrypt a buffer using a previously initialized context. 56 * 57 * @param ctx an AVTEA context 58 * @param dst destination array, can be equal to src 59 * @param src source array, can be equal to dst 60 * @param count number of 8 byte blocks 61 * @param iv initialization vector for CBC mode, if NULL then ECB will be used 62 * @param decrypt 0 for encryption, 1 for decryption 63 */ 64 void av_tea_crypt(struct AVTEA *ctx, uint8_t *dst, const uint8_t *src, 65 int count, uint8_t *iv, int decrypt); 66 67 /** 68 * @} 69 */ 70 71 #endif /* AVUTIL_TEA_H */