2 * Copyright (c) 2013 Arthur Mesh <arthurmesh@gmail.com>
3 * Copyright (c) 2000-2004 Mark R V Murray
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer
11 * in this position and unchanged.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
32 #include <sys/param.h>
33 #include <sys/systm.h>
36 #include <sys/fcntl.h>
37 #include <sys/filio.h>
38 #include <sys/kernel.h>
39 #include <sys/kthread.h>
41 #include <sys/malloc.h>
42 #include <sys/module.h>
43 #include <sys/mutex.h>
47 #include <sys/selinfo.h>
49 #include <sys/unistd.h>
51 #include <machine/bus.h>
52 #include <machine/cpu.h>
54 #include <dev/random/random_adaptors.h>
55 #include <dev/random/randomdev.h>
57 #define RANDOM_MINOR 0
59 static d_close_t random_close;
60 static d_read_t random_read;
61 static d_write_t random_write;
62 static d_ioctl_t random_ioctl;
63 static d_poll_t random_poll;
65 static struct cdevsw random_cdevsw = {
66 .d_version = D_VERSION,
67 .d_close = random_close,
68 .d_read = random_read,
69 .d_write = random_write,
70 .d_ioctl = random_ioctl,
71 .d_poll = random_poll,
75 static struct random_adaptor *random_adaptor;
76 static eventhandler_tag attach_tag;
77 static int random_inited;
80 /* For use with make_dev(9)/destroy_dev(9). */
81 static struct cdev *random_dev;
83 /* Used to fake out unused random calls in random_adaptor */
85 random_null_func(void)
89 struct random_adaptor *
90 random_get_active_adaptor(void)
93 return (random_adaptor);
98 random_close(struct cdev *dev __unused, int flags, int fmt __unused,
101 if ((flags & FWRITE) && (priv_check(td, PRIV_RANDOM_RESEED) == 0)
102 && (securelevel_gt(td->td_ucred, 0) == 0)) {
103 (*random_adaptor->reseed)();
104 random_adaptor->seeded = 1;
105 arc4rand(NULL, 0, 1); /* Reseed arc4random as well. */
113 random_read(struct cdev *dev __unused, struct uio *uio, int flag)
119 if (!random_adaptor->seeded)
120 error = (*random_adaptor->block)(flag);
122 /* The actual read */
125 random_buf = (void *)malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
127 while (uio->uio_resid > 0 && !error) {
128 c = MIN(uio->uio_resid, PAGE_SIZE);
129 c = (*random_adaptor->read)(random_buf, c);
130 error = uiomove(random_buf, c, uio);
133 free(random_buf, M_TEMP);
142 random_write(struct cdev *dev __unused, struct uio *uio, int flag __unused)
147 random_buf = (void *)malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
149 while (uio->uio_resid > 0) {
150 c = MIN((int)uio->uio_resid, PAGE_SIZE);
151 error = uiomove(random_buf, c, uio);
154 (*random_adaptor->write)(random_buf, c);
157 free(random_buf, M_TEMP);
164 random_ioctl(struct cdev *dev __unused, u_long cmd, caddr_t addr __unused,
165 int flags __unused, struct thread *td __unused)
170 /* Really handled in upper layer */
182 random_poll(struct cdev *dev __unused, int events, struct thread *td)
186 if (events & (POLLIN | POLLRDNORM)) {
187 if (random_adaptor->seeded)
188 revents = events & (POLLIN | POLLRDNORM);
190 revents = (*random_adaptor->poll) (events,td);
196 random_initialize(void *p, struct random_adaptor *s)
199 printf("random: <%s> already initialized\n",
200 random_adaptor->ident);
208 printf("random: <%s> initialized\n", s->ident);
210 random_dev = make_dev_credf(MAKEDEV_ETERNAL_KLD, &random_cdevsw,
211 RANDOM_MINOR, NULL, UID_ROOT, GID_WHEEL, 0666, "random");
212 make_dev_alias(random_dev, "urandom"); /* XXX Deprecated */
214 /* mark random(4) as initialized, to avoid being called again */
220 random_modevent(module_t mod __unused, int type, void *data __unused)
226 random_adaptor_choose(&random_adaptor);
228 if (random_adaptor == NULL) {
230 "random: No random adaptor attached, postponing initialization\n");
231 attach_tag = EVENTHANDLER_REGISTER(random_adaptor_attach,
232 random_initialize, NULL, EVENTHANDLER_PRI_ANY);
234 random_initialize(NULL, random_adaptor);
240 if (random_adaptor != NULL) {
241 (*random_adaptor->deinit)();
242 destroy_dev(random_dev);
244 /* Unregister the event handler */
245 if (attach_tag != NULL) {
246 EVENTHANDLER_DEREGISTER(random_adaptor_attach,
263 DEV_MODULE(random, random_modevent, NULL);
264 MODULE_VERSION(random, 1);