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
88
89
|
/*
* Copyright 2017 Timothy Arceri
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*/
#include "detect_os.h"
#if !DETECT_OS_WINDOWS
#if defined(HAVE_GETRANDOM)
#include <sys/random.h>
#endif
#include <unistd.h>
#include <fcntl.h>
#endif
#include <time.h>
#include "rand_xor.h"
/* Super fast random number generator.
*
* This rand_xorshift128plus function by Sebastiano Vigna belongs
* to the public domain.
*/
uint64_t
rand_xorshift128plus(uint64_t seed[2])
{
uint64_t *s = seed;
uint64_t s1 = s[0];
const uint64_t s0 = s[1];
s[0] = s0;
s1 ^= s1 << 23;
s[1] = s1 ^ s0 ^ (s1 >> 18) ^ (s0 >> 5);
return s[1] + s0;
}
void
s_rand_xorshift128plus(uint64_t seed[2], bool randomised_seed)
{
if (!randomised_seed) {
/* Use a fixed seed */
seed[0] = 0x3bffb83978e24f88;
seed[1] = 0x9238d5d56c71cd35;
return;
}
#if !DETECT_OS_WINDOWS
size_t seed_size = sizeof(uint64_t) * 2;
#if defined(HAVE_GETRANDOM)
ssize_t ret = getrandom(seed, seed_size, GRND_NONBLOCK);
if (ret == seed_size)
return;
#endif
int fd = open("/dev/urandom", O_RDONLY);
if (fd >= 0) {
if (read(fd, seed, seed_size) == seed_size) {
close(fd);
return;
}
close(fd);
}
#endif
seed[0] = 0x3bffb83978e24f88;
seed[1] = time(NULL);
}
|
