/*
* An implementation of the TwoFish algorithm
* Copyright (c) 2015 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_TWOFISH_H
#define AVUTIL_TWOFISH_H

#include <stdint.h>


/**
* @file
* @brief Public header for libavutil TWOFISH algorithm
* @defgroup lavu_twofish TWOFISH
* @ingroup lavu_crypto
* @{
*/

extern const int av_twofish_size;

struct AVTWOFISH;

/**
* Allocate an AVTWOFISH context
* To free the struct: av_free(ptr)
*/
struct AVTWOFISH *av_twofish_alloc(void);

/**
* Initialize an AVTWOFISH context.
*
* @param ctx an AVTWOFISH context
* @param key a key of size ranging from 1 to 32 bytes used for encryption/decryption
* @param key_bits number of keybits: 128, 192, 256 If less than the required, padded with zeroes to nearest valid value; return value is 0 if key_bits is 128/192/256, -1 if less than 0, 1 otherwise
*/
int av_twofish_init(struct AVTWOFISH *ctx, const uint8_t *key, int key_bits);

/**
* Encrypt or decrypt a buffer using a previously initialized context
*
* @param ctx an AVTWOFISH context
* @param dst destination array, can be equal to src
* @param src source array, can be equal to dst
* @param count number of 16 byte blocks
* @paran iv initialization vector for CBC mode, NULL for ECB mode
* @param decrypt 0 for encryption, 1 for decryption
*/
void av_twofish_crypt(struct AVTWOFISH *ctx, uint8_t *dst, const uint8_t *src, int count, uint8_t* iv, int decrypt);

/**
* @}
*/
#endif /* AVUTIL_TWOFISH_H */