blob: 735427c109a15229f7750073b4591763d6ab60ca
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 | * Allocate an AVXTEA context. |
41 | */ |
42 | AVXTEA *av_xtea_alloc(void); |
43 | |
44 | /** |
45 | * Initialize an AVXTEA context. |
46 | * |
47 | * @param ctx an AVXTEA context |
48 | * @param key a key of 16 bytes used for encryption/decryption, |
49 | * interpreted as big endian 32 bit numbers |
50 | */ |
51 | void av_xtea_init(struct AVXTEA *ctx, const uint8_t key[16]); |
52 | |
53 | /** |
54 | * Initialize an AVXTEA context. |
55 | * |
56 | * @param ctx an AVXTEA context |
57 | * @param key a key of 16 bytes used for encryption/decryption, |
58 | * interpreted as little endian 32 bit numbers |
59 | */ |
60 | void av_xtea_le_init(struct AVXTEA *ctx, const uint8_t key[16]); |
61 | |
62 | /** |
63 | * Encrypt or decrypt a buffer using a previously initialized context, |
64 | * in big endian format. |
65 | * |
66 | * @param ctx an AVXTEA context |
67 | * @param dst destination array, can be equal to src |
68 | * @param src source array, can be equal to dst |
69 | * @param count number of 8 byte blocks |
70 | * @param iv initialization vector for CBC mode, if NULL then ECB will be used |
71 | * @param decrypt 0 for encryption, 1 for decryption |
72 | */ |
73 | void av_xtea_crypt(struct AVXTEA *ctx, uint8_t *dst, const uint8_t *src, |
74 | int count, uint8_t *iv, int decrypt); |
75 | |
76 | /** |
77 | * Encrypt or decrypt a buffer using a previously initialized context, |
78 | * in little endian format. |
79 | * |
80 | * @param ctx an AVXTEA context |
81 | * @param dst destination array, can be equal to src |
82 | * @param src source array, can be equal to dst |
83 | * @param count number of 8 byte blocks |
84 | * @param iv initialization vector for CBC mode, if NULL then ECB will be used |
85 | * @param decrypt 0 for encryption, 1 for decryption |
86 | */ |
87 | void av_xtea_le_crypt(struct AVXTEA *ctx, uint8_t *dst, const uint8_t *src, |
88 | int count, uint8_t *iv, int decrypt); |
89 | |
90 | /** |
91 | * @} |
92 | */ |
93 | |
94 | #endif /* AVUTIL_XTEA_H */ |
95 |