FFmpeg4/libavutil/tea.h

72 lines
2.0 KiB
C

/*
* A 32-bit implementation of the TEA algorithm
* Copyright (c) 2015 Vesselin Bontchev
*
* 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_TEA_H
#define AVUTIL_TEA_H
#include <stdint.h>
/**
* @file
* @brief Public header for libavutil TEA algorithm
* @defgroup lavu_tea TEA
* @ingroup lavu_crypto
* @{
*/
extern const int av_tea_size;
struct AVTEA;
/**
* Allocate an AVTEA context
* To free the struct: av_free(ptr)
*/
struct AVTEA *av_tea_alloc(void);
/**
* Initialize an AVTEA context.
*
* @param ctx an AVTEA context
* @param key a key of 16 bytes used for encryption/decryption
* @param rounds the number of rounds in TEA (64 is the "standard")
*/
void av_tea_init(struct AVTEA *ctx, const uint8_t key[16], int rounds);
/**
* Encrypt or decrypt a buffer using a previously initialized context.
*
* @param ctx an AVTEA 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_tea_crypt(struct AVTEA *ctx, uint8_t *dst, const uint8_t *src,
int count, uint8_t *iv, int decrypt);
/**
* @}
*/
#endif /* AVUTIL_TEA_H */