blob: dd929bdafdc42b00102ac4db2c38ca5afd607f55
| 1 | /* |
| 2 | * A 32-bit implementation of the TEA algorithm |
| 3 | * Copyright (c) 2015 Vesselin Bontchev |
| 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_TEA_H |
| 23 | #define AVUTIL_TEA_H |
| 24 | |
| 25 | #include <stdint.h> |
| 26 | |
| 27 | /** |
| 28 | * @file |
| 29 | * @brief Public header for libavutil TEA algorithm |
| 30 | * @defgroup lavu_tea TEA |
| 31 | * @ingroup lavu_crypto |
| 32 | * @{ |
| 33 | */ |
| 34 | |
| 35 | extern const int av_tea_size; |
| 36 | |
| 37 | struct AVTEA; |
| 38 | |
| 39 | /** |
| 40 | * Allocate an AVTEA context |
| 41 | * To free the struct: av_free(ptr) |
| 42 | */ |
| 43 | struct AVTEA *av_tea_alloc(void); |
| 44 | |
| 45 | /** |
| 46 | * Initialize an AVTEA context. |
| 47 | * |
| 48 | * @param ctx an AVTEA context |
| 49 | * @param key a key of 16 bytes used for encryption/decryption |
| 50 | * @param rounds the number of rounds in TEA (64 is the "standard") |
| 51 | */ |
| 52 | void av_tea_init(struct AVTEA *ctx, const uint8_t key[16], int rounds); |
| 53 | |
| 54 | /** |
| 55 | * Encrypt or decrypt a buffer using a previously initialized context. |
| 56 | * |
| 57 | * @param ctx an AVTEA context |
| 58 | * @param dst destination array, can be equal to src |
| 59 | * @param src source array, can be equal to dst |
| 60 | * @param count number of 8 byte blocks |
| 61 | * @param iv initialization vector for CBC mode, if NULL then ECB will be used |
| 62 | * @param decrypt 0 for encryption, 1 for decryption |
| 63 | */ |
| 64 | void av_tea_crypt(struct AVTEA *ctx, uint8_t *dst, const uint8_t *src, |
| 65 | int count, uint8_t *iv, int decrypt); |
| 66 | |
| 67 | /** |
| 68 | * @} |
| 69 | */ |
| 70 | |
| 71 | #endif /* AVUTIL_TEA_H */ |
| 72 |