/* * RC4 encryption/decryption/pseudo-random number generator * * This file is part of Libav. * * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Libav is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef AVUTIL_RC4_H #define AVUTIL_RC4_H #include <stdint.h> #include "version.h" /** * @defgroup lavu_rc4 RC4 * @ingroup lavu_crypto * @{ */ #if FF_API_CRYPTO_CONTEXT typedef struct AVRC4 { uint8_t state[256]; int x, y; } AVRC4; #else typedef struct AVRC4 AVRC4; #endif /** * Allocate an AVRC4 context. */ AVRC4 *av_rc4_alloc(void); /** * @brief Initializes an AVRC4 context. * * @param key_bits must be a multiple of 8 * @param decrypt 0 for encryption, 1 for decryption, currently has no effect * @return zero on success, negative value otherwise */ int av_rc4_init(struct AVRC4 *d, const uint8_t *key, int key_bits, int decrypt); /** * @brief Encrypts / decrypts using the RC4 algorithm. * * @param count number of bytes * @param dst destination array, can be equal to src * @param src source array, can be equal to dst, may be NULL * @param iv not (yet) used for RC4, should be NULL * @param decrypt 0 for encryption, 1 for decryption, not (yet) used */ void av_rc4_crypt(struct AVRC4 *d, uint8_t *dst, const uint8_t *src, int count, uint8_t *iv, int decrypt); /** * @} */ #endif /* AVUTIL_RC4_H */