2 * Copyright (c) 2000-2004 Mark R V Murray
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer
10 * in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
31 #include <sys/param.h>
32 #include <sys/systm.h>
35 #include <sys/fcntl.h>
36 #include <sys/filio.h>
37 #include <sys/kernel.h>
38 #include <sys/kthread.h>
40 #include <sys/malloc.h>
41 #include <sys/module.h>
42 #include <sys/mutex.h>
46 #include <sys/selinfo.h>
48 #include <sys/unistd.h>
50 #include <machine/bus.h>
51 #include <machine/cpu.h>
53 #include <dev/random/randomdev.h>
55 #define RANDOM_MINOR 0
57 static d_close_t random_close;
58 static d_read_t random_read;
59 static d_write_t random_write;
60 static d_ioctl_t random_ioctl;
61 static d_poll_t random_poll;
63 static struct cdevsw random_cdevsw = {
64 .d_version = D_VERSION,
65 .d_close = random_close,
66 .d_read = random_read,
67 .d_write = random_write,
68 .d_ioctl = random_ioctl,
69 .d_poll = random_poll,
73 struct random_systat random_systat;
75 /* For use with make_dev(9)/destroy_dev(9). */
76 static struct cdev *random_dev;
78 /* Used to fake out unused random calls in random_systat */
80 random_null_func(void)
86 random_close(struct cdev *dev __unused, int flags, int fmt __unused,
89 if ((flags & FWRITE) && (priv_check(td, PRIV_RANDOM_RESEED) == 0)
90 && (securelevel_gt(td->td_ucred, 0) == 0)) {
91 (*random_systat.reseed)();
92 random_systat.seeded = 1;
93 arc4rand(NULL, 0, 1); /* Reseed arc4random as well. */
101 random_read(struct cdev *dev __unused, struct uio *uio, int flag)
107 if (!random_systat.seeded)
108 error = (*random_systat.block)(flag);
110 /* The actual read */
113 random_buf = (void *)malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
115 while (uio->uio_resid > 0 && !error) {
116 c = MIN(uio->uio_resid, PAGE_SIZE);
117 c = (*random_systat.read)(random_buf, c);
118 error = uiomove(random_buf, c, uio);
121 free(random_buf, M_TEMP);
130 random_write(struct cdev *dev __unused, struct uio *uio, int flag __unused)
135 random_buf = (void *)malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
137 while (uio->uio_resid > 0) {
138 c = MIN((int)uio->uio_resid, PAGE_SIZE);
139 error = uiomove(random_buf, c, uio);
142 (*random_systat.write)(random_buf, c);
145 free(random_buf, M_TEMP);
152 random_ioctl(struct cdev *dev __unused, u_long cmd, caddr_t addr __unused,
153 int flags __unused, struct thread *td __unused)
158 /* Really handled in upper layer */
170 random_poll(struct cdev *dev __unused, int events, struct thread *td)
174 if (events & (POLLIN | POLLRDNORM)) {
175 if (random_systat.seeded)
176 revents = events & (POLLIN | POLLRDNORM);
178 revents = (*random_systat.poll) (events,td);
185 random_modevent(module_t mod __unused, int type, void *data __unused)
191 random_ident_hardware(&random_systat);
192 (*random_systat.init)();
195 printf("random: <entropy source, %s>\n",
196 random_systat.ident);
198 random_dev = make_dev_credf(MAKEDEV_ETERNAL_KLD, &random_cdevsw,
199 RANDOM_MINOR, NULL, UID_ROOT, GID_WHEEL, 0666, "random");
200 make_dev_alias(random_dev, "urandom"); /* XXX Deprecated */
205 (*random_systat.deinit)();
207 destroy_dev(random_dev);
222 DEV_MODULE(random, random_modevent, NULL);
223 MODULE_VERSION(random, 1);