FFmpeg
rc4.h
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1 /*
2  * RC4 encryption/decryption/pseudo-random number generator
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #ifndef AVUTIL_RC4_H
22 #define AVUTIL_RC4_H
23 
24 #include <stdint.h>
25 
26 /**
27  * @defgroup lavu_rc4 RC4
28  * @ingroup lavu_crypto
29  * @{
30  */
31 
32 typedef struct AVRC4 {
33  uint8_t state[256];
34  int x, y;
35 } AVRC4;
36 
37 /**
38  * Allocate an AVRC4 context.
39  */
40 AVRC4 *av_rc4_alloc(void);
41 
42 /**
43  * @brief Initializes an AVRC4 context.
44  *
45  * @param key_bits must be a multiple of 8
46  * @param decrypt 0 for encryption, 1 for decryption, currently has no effect
47  * @return zero on success, negative value otherwise
48  */
49 int av_rc4_init(struct AVRC4 *d, const uint8_t *key, int key_bits, int decrypt);
50 
51 /**
52  * @brief Encrypts / decrypts using the RC4 algorithm.
53  *
54  * @param count number of bytes
55  * @param dst destination array, can be equal to src
56  * @param src source array, can be equal to dst, may be NULL
57  * @param iv not (yet) used for RC4, should be NULL
58  * @param decrypt 0 for encryption, 1 for decryption, not (yet) used
59  */
60 void av_rc4_crypt(struct AVRC4 *d, uint8_t *dst, const uint8_t *src, int count, uint8_t *iv, int decrypt);
61 
62 /**
63  * @}
64  */
65 
66 #endif /* AVUTIL_RC4_H */
AVRC4::x
int x
Definition: rc4.h:34
AVRC4
Definition: rc4.h:32
AVRC4::state
uint8_t state[256]
Definition: rc4.h:33
key
const char * key
Definition: hwcontext_opencl.c:168
src
#define src
Definition: vp8dsp.c:255
av_rc4_alloc
AVRC4 * av_rc4_alloc(void)
Allocate an AVRC4 context.
Definition: rc4.c:28
AVRC4::y
int y
Definition: rc4.h:34
av_rc4_crypt
void av_rc4_crypt(struct AVRC4 *d, uint8_t *dst, const uint8_t *src, int count, uint8_t *iv, int decrypt)
Encrypts / decrypts using the RC4 algorithm.
Definition: rc4.c:54
uint8_t
uint8_t
Definition: audio_convert.c:194
av_rc4_init
int av_rc4_init(struct AVRC4 *d, const uint8_t *key, int key_bits, int decrypt)
Initializes an AVRC4 context.
Definition: rc4.c:33