ffmpeg/libavutil/xtea.h

   1 /*
   2  * A 32-bit implementation of the XTEA algorithm
   3  * Copyright (c) 2012 Samuel Pitoiset
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #ifndef AVUTIL_XTEA_H
  23 #define AVUTIL_XTEA_H
  24
  25 #include <stdint.h>
  26
  27 /**
  28  * @file
  29  * @brief Public header for libavutil XTEA algorithm
  30  * @defgroup lavu_xtea XTEA
  31  * @ingroup lavu_crypto
  32  * @{
  33  */
  34
  35 typedef struct AVXTEA {
  36     uint32_t key[16];
  37 } AVXTEA;
  38
  39 /**
  40  * Initialize an AVXTEA context.
  41  *
  42  * @param ctx an AVXTEA context
  43  * @param key a key of 16 bytes used for encryption/decryption
  44  */
  45 void av_xtea_init(struct AVXTEA *ctx, const uint8_t key[16]);
  46
  47 /**
  48  * Encrypt or decrypt a buffer using a previously initialized context.
  49  *
  50  * @param ctx an AVXTEA context
  51  * @param dst destination array, can be equal to src
  52  * @param src source array, can be equal to dst
  53  * @param count number of 8 byte blocks
  54  * @param iv initialization vector for CBC mode, if NULL then ECB will be used
  55  * @param decrypt 0 for encryption, 1 for decryption
  56  */
  57 void av_xtea_crypt(struct AVXTEA *ctx, uint8_t *dst, const uint8_t *src,
  58                    int count, uint8_t *iv, int decrypt);
  59
  60 /**
  61  * @}
  62  */
  63
  64 #endif /* AVUTIL_XTEA_H */