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 everywhere */
133 # define FD_SETSIZE (8*sizeof(fd_set))
136 #if defined(OPENSSL_SYS_VOS)
138 /* The following algorithm repeatedly samples the real-time clock
139 (RTC) to generate a sequence of unpredictable data. The algorithm
140 relies upon the uneven execution speed of the code (due to factors
141 such as cache misses, interrupts, bus activity, and scheduling) and
142 upon the rather large relative difference between the speed of the
143 clock and the rate at which it can be read.
145 If this code is ported to an environment where execution speed is
146 more constant or where the RTC ticks at a much slower rate, or the
147 clock can be read with fewer instructions, it is likely that the
148 results would be far more predictable.
150 As a precaution, we generate 4 times the minimum required amount of
163 #ifdef OPENSSL_SYS_VOS_HPPA
165 extern void s$
sleep (long *_duration
, short int *_code
);
167 #ifdef OPENSSL_SYS_VOS_IA32
169 extern void s$
sleep2 (long long *_duration
, short int *_code
);
171 #error "Unsupported Platform."
172 #endif /* OPENSSL_SYS_VOS_IA32 */
173 #endif /* OPENSSL_SYS_VOS_HPPA */
175 /* Seed with the gid, pid, and uid, to ensure *some*
176 variation between different processes. */
179 RAND_add (&curr_gid
, sizeof curr_gid
, 1);
183 RAND_add (&curr_pid
, sizeof curr_pid
, 1);
187 RAND_add (&curr_uid
, sizeof curr_uid
, 1);
190 for (i
=0; i
<(ENTROPY_NEEDED
*4); i
++)
192 /* burn some cpu; hope for interrupts, cache
193 collisions, bus interference, etc. */
195 ts
.tv_nsec
= random ();
197 #ifdef OPENSSL_SYS_VOS_HPPA
198 /* sleep for 1/1024 of a second (976 us). */
200 s$
sleep (&duration
, &code
);
202 #ifdef OPENSSL_SYS_VOS_IA32
203 /* sleep for 1/65536 of a second (15 us). */
205 s$
sleep2 (&duration
, &code
);
206 #endif /* OPENSSL_SYS_VOS_IA32 */
207 #endif /* OPENSSL_SYS_VOS_HPPA */
209 /* get wall clock time. */
210 clock_gettime (CLOCK_REALTIME
, &ts
);
213 v
= (unsigned char) (ts
.tv_nsec
% 256);
214 RAND_add (&v
, sizeof v
, 1);
219 #elif defined __OpenBSD__
222 u_int32_t rnd
= 0, i
;
223 unsigned char buf
[ENTROPY_NEEDED
];
225 for (i
= 0; i
< sizeof(buf
); i
++) {
231 RAND_add(buf
, sizeof(buf
), ENTROPY_NEEDED
);
232 memset(buf
, 0, sizeof(buf
));
236 #else /* !defined(__OpenBSD__) */
240 pid_t curr_pid
= getpid();
241 #if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
242 unsigned char tmpbuf
[ENTROPY_NEEDED
];
246 static const char *randomfiles
[] = { DEVRANDOM
};
247 struct stat randomstats
[sizeof(randomfiles
)/sizeof(randomfiles
[0])];
252 static const char *egdsockets
[] = { DEVRANDOM_EGD
, NULL
};
253 const char **egdsocket
= NULL
;
257 memset(randomstats
,0,sizeof(randomstats
));
258 /* Use a random entropy pool device. Linux, FreeBSD and OpenBSD
259 * have this. Use /dev/urandom if you can as /dev/random may block
260 * if it runs out of random entries. */
262 for (i
= 0; (i
< sizeof(randomfiles
)/sizeof(randomfiles
[0])) &&
263 (n
< ENTROPY_NEEDED
); i
++)
265 if ((fd
= open(randomfiles
[i
], O_RDONLY
272 #ifdef O_NOCTTY /* If it happens to be a TTY (god forbid), do not make it
273 our controlling tty */
278 int usec
= 10*1000; /* spend 10ms on each file */
281 struct stat
*st
=&randomstats
[i
];
283 /* Avoid using same input... Used to be O_NOFOLLOW
284 * above, but it's not universally appropriate... */
285 if (fstat(fd
,st
) != 0) { close(fd
); continue; }
288 if (randomstats
[j
].st_ino
==st
->st_ino
&&
289 randomstats
[j
].st_dev
==st
->st_dev
)
292 if (j
<i
) { close(fd
); continue; }
298 #if defined(OPENSSL_SYS_BEOS_R5)
299 /* select() is broken in BeOS R5, so we simply
300 * try to read something and snooze if we couldn't */
303 #elif defined(OPENSSL_SYS_LINUX)
308 pset
.events
= POLLIN
;
311 if (poll(&pset
, 1, usec
/ 1000) < 0)
314 try_read
= (pset
.revents
& POLLIN
) != 0;
324 if (FD_SETSIZE
> 0 && (unsigned)fd
>= FD_SETSIZE
)
326 /* can't use select, so just try to read once anyway */
334 if (select(fd
+1,&fset
,NULL
,NULL
,&t
) >= 0)
337 if (FD_ISSET(fd
, &fset
))
347 r
= read(fd
,(unsigned char *)tmpbuf
+n
, ENTROPY_NEEDED
-n
);
350 #if defined(OPENSSL_SYS_BEOS_R5)
358 /* Some Unixen will update t in select(), some
359 won't. For those who won't, or if we
360 didn't use select() in the first place,
361 give up here, otherwise, we will do
362 this once again for the remaining
368 (errno
== EINTR
|| errno
== EAGAIN
)) && usec
!= 0 && n
< ENTROPY_NEEDED
);
373 #endif /* defined(DEVRANDOM) */
376 /* Use an EGD socket to read entropy from an EGD or PRNGD entropy
377 * collecting daemon. */
379 for (egdsocket
= egdsockets
; *egdsocket
&& n
< ENTROPY_NEEDED
; egdsocket
++)
383 r
= RAND_query_egd_bytes(*egdsocket
, (unsigned char *)tmpbuf
+n
,
388 #endif /* defined(DEVRANDOM_EGD) */
390 #if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
393 RAND_add(tmpbuf
,sizeof tmpbuf
,(double)n
);
394 OPENSSL_cleanse(tmpbuf
,n
);
398 /* put in some default random data, we need more than just this */
400 RAND_add(&l
,sizeof(l
),0.0);
402 RAND_add(&l
,sizeof(l
),0.0);
405 RAND_add(&l
,sizeof(l
),0.0);
407 #if defined(OPENSSL_SYS_BEOS)
410 get_system_info(&sysInfo
);
411 RAND_add(&sysInfo
,sizeof(sysInfo
),0);
415 #if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
422 #endif /* defined(__OpenBSD__) */
423 #endif /* !(defined(OPENSSL_SYS_WINDOWS) || defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VMS) || defined(OPENSSL_SYS_OS2) || defined(OPENSSL_SYS_VXWORKS) || defined(OPENSSL_SYS_NETWARE)) */
426 #if defined(OPENSSL_SYS_VXWORKS)