text: /*
   * 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 */
  