/*
* A 32-bit implementation of the XTEA algorithm
* Copyright (c) 2012 Samuel Pitoiset
*
* 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_XTEA_H
#define AVUTIL_XTEA_H
#include <stdint.h>
/**
* @file
* @brief Public header for libavutil XTEA algorithm
* @defgroup lavu_xtea XTEA
* @ingroup lavu_crypto
* @{
*/
typedef struct AVXTEA {
uint32_t key[16];
} AVXTEA;
/**
* Allocate an AVXTEA context.
*/
AVXTEA *av_xtea_alloc(void);
/**
* Initialize an AVXTEA context.
*
* @param ctx an AVXTEA context
* @param key a key of 16 bytes used for encryption/decryption,
* interpreted as big endian 32 bit numbers
*/
void av_xtea_init(struct AVXTEA *ctx, const uint8_t key[16]);
/**
* Initialize an AVXTEA context.
*
* @param ctx an AVXTEA context
* @param key a key of 16 bytes used for encryption/decryption,
* interpreted as little endian 32 bit numbers
*/
void av_xtea_le_init(struct AVXTEA *ctx, const uint8_t key[16]);
/**
* Encrypt or decrypt a buffer using a previously initialized context,
* in big endian format.
*
* @param ctx an AVXTEA 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, if NULL then ECB will be used
* @param decrypt 0 for encryption, 1 for decryption
*/
void av_xtea_crypt(struct AVXTEA *ctx, uint8_t *dst, const uint8_t *src,
int count, uint8_t *iv, int decrypt);
/**
* Encrypt or decrypt a buffer using a previously initialized context,
* in little endian format.
*
* @param ctx an AVXTEA 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, if NULL then ECB will be used
* @param decrypt 0 for encryption, 1 for decryption
*/
void av_xtea_le_crypt(struct AVXTEA *ctx, uint8_t *dst, const uint8_t *src,
int count, uint8_t *iv, int decrypt);
/**
* @}
*/
#endif /* AVUTIL_XTEA_H */