1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
|
/*
* AES-CTR cipher
* Copyright (c) 2015 Eran Kornblau <erankor at gmail dot com>
*
* 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_AES_CTR_H
#define AVUTIL_AES_CTR_H
#include <stdint.h>
#include "attributes.h"
#define AES_CTR_KEY_SIZE (16)
#define AES_CTR_IV_SIZE (8)
struct AVAESCTR;
/**
* Allocate an AVAESCTR context.
*/
struct AVAESCTR *av_aes_ctr_alloc(void);
/**
* Initialize an AVAESCTR context.
* @param key encryption key, must have a length of AES_CTR_KEY_SIZE
*/
int av_aes_ctr_init(struct AVAESCTR *a, const uint8_t *key);
/**
* Release an AVAESCTR context.
*/
void av_aes_ctr_free(struct AVAESCTR *a);
/**
* Process a buffer using a previously initialized context.
* @param dst destination array, can be equal to src
* @param src source array, can be equal to dst
* @param size the size of src and dst
*/
void av_aes_ctr_crypt(struct AVAESCTR *a, uint8_t *dst, const uint8_t *src, int size);
/**
* Get the current iv
*/
const uint8_t* av_aes_ctr_get_iv(struct AVAESCTR *a);
/**
* Generate a random iv
*/
void av_aes_ctr_set_random_iv(struct AVAESCTR *a);
/**
* Forcefully change the 8-byte iv
*/
void av_aes_ctr_set_iv(struct AVAESCTR *a, const uint8_t* iv);
/**
* Forcefully change the "full" 16-byte iv, including the counter
*/
void av_aes_ctr_set_full_iv(struct AVAESCTR *a, const uint8_t* iv);
/**
* Increment the top 64 bit of the iv (performed after each frame)
*/
void av_aes_ctr_increment_iv(struct AVAESCTR *a);
/**
* @}
*/
#endif /* AVUTIL_AES_CTR_H */
|