1 /* crypto/rand/rand_unix.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
58 /* ====================================================================
59 * Copyright (c) 1998-2006 The OpenSSL Project. All rights reserved.
61 * Redistribution and use in source and binary forms, with or without
62 * modification, are permitted provided that the following conditions
65 * 1. Redistributions of source code must retain the above copyright
66 * notice, this list of conditions and the following disclaimer.
68 * 2. Redistributions in binary form must reproduce the above copyright
69 * notice, this list of conditions and the following disclaimer in
70 * the documentation and/or other materials provided with the
73 * 3. All advertising materials mentioning features or use of this
74 * software must display the following acknowledgment:
75 * "This product includes software developed by the OpenSSL Project
76 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
78 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
79 * endorse or promote products derived from this software without
80 * prior written permission. For written permission, please contact
81 * openssl-core@openssl.org.
83 * 5. Products derived from this software may not be called "OpenSSL"
84 * nor may "OpenSSL" appear in their names without prior written
85 * permission of the OpenSSL Project.
87 * 6. Redistributions of any form whatsoever must retain the following
89 * "This product includes software developed by the OpenSSL Project
90 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
92 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
93 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
95 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
96 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
97 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
98 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
99 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
101 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
102 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
103 * OF THE POSSIBILITY OF SUCH DAMAGE.
104 * ====================================================================
106 * This product includes cryptographic software written by Eric Young
107 * (eay@cryptsoft.com). This product includes software written by Tim
108 * Hudson (tjh@cryptsoft.com).
115 #include "cryptlib.h"
116 #include <openssl/rand.h>
117 #include "rand_lcl.h"
119 #if !(defined(OPENSSL_SYS_WINDOWS) || defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VMS) || defined(OPENSSL_SYS_OS2) || defined(OPENSSL_SYS_VXWORKS) || defined(OPENSSL_SYS_NETWARE))
121 # include <sys/types.h>
122 # include <sys/time.h>
123 # include <sys/times.h>
124 # include <sys/stat.h>
128 # if defined(OPENSSL_SYS_LINUX) /* should actually be available virtually
134 # define FD_SETSIZE (8*sizeof(fd_set))
137 # if defined(OPENSSL_SYS_VOS)
140 * The following algorithm repeatedly samples the real-time clock (RTC) to
141 * generate a sequence of unpredictable data. The algorithm relies upon the
142 * uneven execution speed of the code (due to factors such as cache misses,
143 * interrupts, bus activity, and scheduling) and upon the rather large
144 * relative difference between the speed of the clock and the rate at which
147 * If this code is ported to an environment where execution speed is more
148 * constant or where the RTC ticks at a much slower rate, or the clock can be
149 * read with fewer instructions, it is likely that the results would be far
152 * As a precaution, we generate 4 times the minimum required amount of seed
166 # ifdef OPENSSL_SYS_VOS_HPPA
168 extern void s$sleep(long *_duration, short int *_code);
170 # ifdef OPENSSL_SYS_VOS_IA32
172 extern void s$sleep2(long long *_duration, short int *_code);
174 # error "Unsupported Platform."
175 # endif /* OPENSSL_SYS_VOS_IA32 */
176 # endif /* OPENSSL_SYS_VOS_HPPA */
179 * Seed with the gid, pid, and uid, to ensure *some* variation between
180 * different processes.
184 RAND_add(&curr_gid, sizeof curr_gid, 1);
188 RAND_add(&curr_pid, sizeof curr_pid, 1);
192 RAND_add(&curr_uid, sizeof curr_uid, 1);
195 for (i = 0; i < (ENTROPY_NEEDED * 4); i++) {
197 * burn some cpu; hope for interrupts, cache collisions, bus
200 for (k = 0; k < 99; k++)
201 ts.tv_nsec = random();
203 # ifdef OPENSSL_SYS_VOS_HPPA
204 /* sleep for 1/1024 of a second (976 us). */
206 s$sleep(&duration, &code);
208 # ifdef OPENSSL_SYS_VOS_IA32
209 /* sleep for 1/65536 of a second (15 us). */
211 s$sleep2(&duration, &code);
212 # endif /* OPENSSL_SYS_VOS_IA32 */
213 # endif /* OPENSSL_SYS_VOS_HPPA */
215 /* get wall clock time. */
216 clock_gettime(CLOCK_REALTIME, &ts);
219 v = (unsigned char)(ts.tv_nsec % 256);
220 RAND_add(&v, sizeof v, 1);
225 # elif defined __OpenBSD__
228 u_int32_t rnd = 0, i;
229 unsigned char buf[ENTROPY_NEEDED];
231 for (i = 0; i < sizeof(buf); i++) {
237 RAND_add(buf, sizeof(buf), ENTROPY_NEEDED);
238 OPENSSL_cleanse(buf, sizeof(buf));
242 # else /* !defined(__OpenBSD__) */
246 pid_t curr_pid = getpid();
247 # if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
248 unsigned char tmpbuf[ENTROPY_NEEDED];
252 static const char *randomfiles[] = { DEVRANDOM };
253 struct stat randomstats[sizeof(randomfiles) / sizeof(randomfiles[0])];
257 # ifdef DEVRANDOM_EGD
258 static const char *egdsockets[] = { DEVRANDOM_EGD, NULL };
259 const char **egdsocket = NULL;
263 memset(randomstats, 0, sizeof(randomstats));
265 * Use a random entropy pool device. Linux, FreeBSD and OpenBSD have
266 * this. Use /dev/urandom if you can as /dev/random may block if it runs
267 * out of random entries.
270 for (i = 0; (i < sizeof(randomfiles) / sizeof(randomfiles[0])) &&
271 (n < ENTROPY_NEEDED); i++) {
272 if ((fd = open(randomfiles[i], O_RDONLY
279 # ifdef O_NOCTTY /* If it happens to be a TTY (god forbid), do
280 * not make it our controlling tty */
284 int usec = 10 * 1000; /* spend 10ms on each file */
287 struct stat *st = &randomstats[i];
290 * Avoid using same input... Used to be O_NOFOLLOW above, but
291 * it's not universally appropriate...
293 if (fstat(fd, st) != 0) {
297 for (j = 0; j < i; j++) {
298 if (randomstats[j].st_ino == st->st_ino &&
299 randomstats[j].st_dev == st->st_dev)
310 # if defined(OPENSSL_SYS_BEOS_R5)
312 * select() is broken in BeOS R5, so we simply try to read
313 * something and snooze if we couldn't
317 # elif defined(OPENSSL_SYS_LINUX)
322 pset.events = POLLIN;
325 if (poll(&pset, 1, usec / 1000) < 0)
328 try_read = (pset.revents & POLLIN) != 0;
338 if (FD_SETSIZE > 0 && (unsigned)fd >= FD_SETSIZE) {
340 * can't use select, so just try to read once anyway
347 if (select(fd + 1, &fset, NULL, NULL, &t) >= 0) {
349 if (FD_ISSET(fd, &fset))
357 r = read(fd, (unsigned char *)tmpbuf + n,
361 # if defined(OPENSSL_SYS_BEOS_R5)
369 * Some Unixen will update t in select(), some won't. For
370 * those who won't, or if we didn't use select() in the first
371 * place, give up here, otherwise, we will do this once again
372 * for the remaining time.
374 if (usec == 10 * 1000)
378 (errno == EINTR || errno == EAGAIN)) && usec != 0
379 && n < ENTROPY_NEEDED);
384 # endif /* defined(DEVRANDOM) */
386 # ifdef DEVRANDOM_EGD
388 * Use an EGD socket to read entropy from an EGD or PRNGD entropy
392 for (egdsocket = egdsockets; *egdsocket && n < ENTROPY_NEEDED;
396 r = RAND_query_egd_bytes(*egdsocket, (unsigned char *)tmpbuf + n,
401 # endif /* defined(DEVRANDOM_EGD) */
403 # if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
405 RAND_add(tmpbuf, sizeof tmpbuf, (double)n);
406 OPENSSL_cleanse(tmpbuf, n);
410 /* put in some default random data, we need more than just this */
412 RAND_add(&l, sizeof(l), 0.0);
414 RAND_add(&l, sizeof(l), 0.0);
417 RAND_add(&l, sizeof(l), 0.0);
419 # if defined(OPENSSL_SYS_BEOS)
422 get_system_info(&sysInfo);
423 RAND_add(&sysInfo, sizeof(sysInfo), 0);
427 # if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
434 # endif /* defined(__OpenBSD__) */
435 #endif /* !(defined(OPENSSL_SYS_WINDOWS) ||
436 * defined(OPENSSL_SYS_WIN32) ||
437 * defined(OPENSSL_SYS_VMS) ||
438 * defined(OPENSSL_SYS_OS2) ||
439 * defined(OPENSSL_SYS_VXWORKS) ||
440 * defined(OPENSSL_SYS_NETWARE)) */
442 #if defined(OPENSSL_SYS_VXWORKS)