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
|
/*
* Copyright (c) 1999-2000 Damien Miller. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Markus Friedl.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "includes.h"
#include <openssl/rand.h>
#include <openssl/rc4.h>
#ifndef HAVE_ARC4RANDOM
/* Size of key to use */
#define SEED_SIZE 20
/* Number of bytes to reseed after */
#define REKEY_BYTES (1 << 18)
static int rc4_ready = 0;
static RC4_KEY rc4;
unsigned int arc4random(void)
{
unsigned int r = 0;
if (rc4_ready <= 0)
arc4random_stir();
RC4(&rc4, sizeof(r), (unsigned char *)&r, (unsigned char *)&r);
rc4_ready -= sizeof(r);
return(r);
}
void arc4random_stir(void)
{
unsigned char rand_buf[SEED_SIZE];
memset(&rc4, 0, sizeof(rc4));
seed_rng();
RAND_bytes(rand_buf, sizeof(rand_buf));
RC4_set_key(&rc4, sizeof(rand_buf), rand_buf);
memset(rand_buf, 0, sizeof(rand_buf));
rc4_ready = REKEY_BYTES;
}
#endif /* !HAVE_ARC4RANDOM */
|
