/*
* An implementation of the CAST128 algorithm as mentioned in RFC2144
* Copyright (c) 2014 Supraja Meedinti
*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/

#ifndef AVUTIL_CAST5_H
#define AVUTIL_CAST5_H

#include <stdint.h>


/**
* @file
* @brief Public header for libavutil CAST5 algorithm
* @defgroup lavu_cast5 CAST5
* @ingroup lavu_crypto
* @{
*/

extern const int av_cast5_size;

struct AVCAST5;

/**
* Allocate an AVCAST5 context
* To free the struct: av_free(ptr)
*/
struct AVCAST5 *av_cast5_alloc(void);
/**
* Initialize an AVCAST5 context.
*
* @param ctx an AVCAST5 context
* @param key a key of 5,6,...16 bytes used for encryption/decryption
* @param key_bits number of keybits: possible are 40,48,...,128
*/
int av_cast5_init(struct AVCAST5 *ctx, const uint8_t *key, int key_bits);

/**
* Encrypt or decrypt a buffer using a previously initialized context, ECB mode only
*
* @param ctx an AVCAST5 context
* @param dst destination array, can be equal to src
* @param src source array, can be equal to dst
* @param count number of 8 byte blocks
* @param decrypt 0 for encryption, 1 for decryption
*/
void av_cast5_crypt(struct AVCAST5 *ctx, uint8_t *dst, const uint8_t *src, int count, int decrypt);

/**
* Encrypt or decrypt a buffer using a previously initialized context
*
* @param ctx an AVCAST5 context
* @param dst destination array, can be equal to src
* @param src source array, can be equal to dst
* @param count number of 8 byte blocks
* @param iv initialization vector for CBC mode, NULL for ECB mode
* @param decrypt 0 for encryption, 1 for decryption
*/
void av_cast5_crypt2(struct AVCAST5 *ctx, uint8_t *dst, const uint8_t *src, int count, uint8_t *iv, int decrypt);
/**
* @}
*/
#endif /* AVUTIL_CAST5_H */