1/* 2 * RC4 encryption/decryption/pseudo-random number generator 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_RC4_H 22#define AVUTIL_RC4_H 23 24#include <stdint.h> 25 26struct AVRC4 { 27 uint8_t state[256]; 28 int x, y; 29}; 30 31/** 32 * @brief Initializes an AVRC4 context. 33 * 34 * @param key_bits must be a multiple of 8 35 * @param decrypt 0 for encryption, 1 for decryption, currently has no effect 36 */ 37int av_rc4_init(struct AVRC4 *d, const uint8_t *key, int key_bits, int decrypt); 38 39/** 40 * @brief Encrypts / decrypts using the RC4 algorithm. 41 * 42 * @param count number of bytes 43 * @param dst destination array, can be equal to src 44 * @param src source array, can be equal to dst, may be NULL 45 * @param iv not (yet) used for RC4, should be NULL 46 * @param decrypt 0 for encryption, 1 for decryption, not (yet) used 47 */ 48void av_rc4_crypt(struct AVRC4 *d, uint8_t *dst, const uint8_t *src, int count, uint8_t *iv, int decrypt); 49 50#endif /* AVUTIL_RC4_H */ 51