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
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
|
/*
* rngd_linux.c -- Entropy sink for the Linux Kernel (/dev/random)
*
* Copyright (C) 2001 Philipp Rumpf
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA
*/
#define _GNU_SOURCE
#ifndef HAVE_CONFIG_H
#error Invalid or missing autoconf build environment
#endif
#include "rng-tools-config.h"
#include <unistd.h>
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <syslog.h>
#include <sys/ioctl.h>
#include <sys/poll.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/time.h>
#include <time.h>
#include <linux/types.h>
#include <linux/random.h>
#include <string.h>
#include "rngd.h"
#include "fips.h"
#include "exits.h"
#include "rngd_linux.h"
extern struct rng *rng_list;
/* Kernel output device */
static int random_fd;
/*
* Get the default watermark
*/
int default_watermark(void)
{
char psbuf[64], *p;
unsigned long ps;
FILE *f;
size_t l;
unsigned int wm = 2048; /* Default guess */
f = fopen("/proc/sys/kernel/random/poolsize", "r");
if (!f)
goto err;
l = fread(psbuf, 1, sizeof psbuf, f);
if (ferror(f) || !feof(f) || l == 0)
goto err;
if (psbuf[l-1] != '\n')
goto err;
psbuf[l-1] = '\0';
ps = strtoul(psbuf, &p, 0);
if (*p)
goto err;
wm = ps*3/4;
err:
if (f)
fclose(f);
return wm;
}
/*
* Initialize the interface to the Linux Kernel
* entropy pool (through /dev/random)
*
* randomdev is the path to the random device
*/
void init_kernel_rng(const char* randomdev)
{
FILE *f;
int err;
random_fd = open(randomdev, O_RDWR);
if (random_fd == -1) {
message(LOG_DAEMON|LOG_ERR, "can't open %s: %s",
randomdev, strerror(errno));
exit(EXIT_USAGE);
}
f = fopen("/proc/sys/kernel/random/write_wakeup_threshold", "w");
if (!f) {
err = 1;
} else {
fprintf(f, "%u\n", arguments->fill_watermark);
/* Note | not || here... we always want to close the file */
err = ferror(f) | fclose(f);
}
if (err) {
message(LOG_DAEMON|LOG_WARNING,
"unable to adjust write_wakeup_threshold: %s",
strerror(errno));
}
}
void random_add_entropy(void *buf, size_t size)
{
struct {
int ent_count;
int size;
unsigned char data[size];
} entropy;
entropy.ent_count = size * 8;
entropy.size = size;
memcpy(entropy.data, buf, size);
if (ioctl(random_fd, RNDADDENTROPY, &entropy) != 0) {
message(LOG_DAEMON|LOG_ERR, "RNDADDENTROPY failed: %s\n",
strerror(errno));
exit(1);
}
}
void random_sleep(void)
{
struct pollfd pfd = {
fd: random_fd,
events: POLLOUT,
};
poll(&pfd, 1, -1);
}
void src_list_add(struct rng *ent_src)
{
if (rng_list) {
struct rng *iter;
iter = rng_list;
while (iter->next) {
iter = iter->next;
}
iter->next = ent_src;
} else {
rng_list = ent_src;
}
}
|
