1/* crypto/rand/rand_unix.c */
2/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
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.
8 *
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).
15 *
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.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
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)"
40 *
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
51 * SUCH DAMAGE.
52 *
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.]
57 */
58/* ====================================================================
59 * Copyright (c) 1998-2006 The OpenSSL Project.  All rights reserved.
60 *
61 * Redistribution and use in source and binary forms, with or without
62 * modification, are permitted provided that the following conditions
63 * are met:
64 *
65 * 1. Redistributions of source code must retain the above copyright
66 *    notice, this list of conditions and the following disclaimer.
67 *
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
71 *    distribution.
72 *
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/)"
77 *
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.
82 *
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.
86 *
87 * 6. Redistributions of any form whatsoever must retain the following
88 *    acknowledgment:
89 *    "This product includes software developed by the OpenSSL Project
90 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
91 *
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 * ====================================================================
105 *
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).
109 *
110 */
111#include <stdio.h>
112
113#define USE_SOCKETS
114#include "e_os.h"
115#include "cryptlib.h"
116#include <openssl/rand.h>
117#include "rand_lcl.h"
118
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))
120
121#include <sys/types.h>
122#include <sys/time.h>
123#include <sys/times.h>
124#include <sys/stat.h>
125#include <fcntl.h>
126#include <unistd.h>
127#include <time.h>
128#if defined(OPENSSL_SYS_LINUX) /* should actually be available virtually everywhere */
129# include <poll.h>
130#endif
131#include <limits.h>
132#ifndef FD_SETSIZE
133# define FD_SETSIZE (8*sizeof(fd_set))
134#endif
135
136#if defined(OPENSSL_SYS_VOS)
137
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.
144
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.
149
150   As a precaution, we generate 4 times the minimum required amount of
151   seed data.  */
152
153int RAND_poll(void)
154{
155	short int code;
156	gid_t curr_gid;
157	pid_t curr_pid;
158	uid_t curr_uid;
159	int i, k;
160	struct timespec ts;
161	unsigned char v;
162
163#ifdef OPENSSL_SYS_VOS_HPPA
164	long duration;
165	extern void s$sleep (long *_duration, short int *_code);
166#else
167#ifdef OPENSSL_SYS_VOS_IA32
168	long long duration;
169	extern void s$sleep2 (long long *_duration, short int *_code);
170#else
171#error "Unsupported Platform."
172#endif /* OPENSSL_SYS_VOS_IA32 */
173#endif /* OPENSSL_SYS_VOS_HPPA */
174
175	/* Seed with the gid, pid, and uid, to ensure *some*
176	   variation between different processes.  */
177
178	curr_gid = getgid();
179	RAND_add (&curr_gid, sizeof curr_gid, 1);
180	curr_gid = 0;
181
182	curr_pid = getpid();
183	RAND_add (&curr_pid, sizeof curr_pid, 1);
184	curr_pid = 0;
185
186	curr_uid = getuid();
187	RAND_add (&curr_uid, sizeof curr_uid, 1);
188	curr_uid = 0;
189
190	for (i=0; i<(ENTROPY_NEEDED*4); i++)
191	{
192		/* burn some cpu; hope for interrupts, cache
193		   collisions, bus interference, etc.  */
194		for (k=0; k<99; k++)
195			ts.tv_nsec = random ();
196
197#ifdef OPENSSL_SYS_VOS_HPPA
198		/* sleep for 1/1024 of a second (976 us).  */
199		duration = 1;
200		s$sleep (&duration, &code);
201#else
202#ifdef OPENSSL_SYS_VOS_IA32
203		/* sleep for 1/65536 of a second (15 us).  */
204		duration = 1;
205		s$sleep2 (&duration, &code);
206#endif /* OPENSSL_SYS_VOS_IA32 */
207#endif /* OPENSSL_SYS_VOS_HPPA */
208
209		/* get wall clock time.  */
210		clock_gettime (CLOCK_REALTIME, &ts);
211
212		/* take 8 bits */
213		v = (unsigned char) (ts.tv_nsec % 256);
214		RAND_add (&v, sizeof v, 1);
215		v = 0;
216	}
217	return 1;
218}
219#elif defined __OpenBSD__
220int RAND_poll(void)
221{
222	u_int32_t rnd = 0, i;
223	unsigned char buf[ENTROPY_NEEDED];
224
225	for (i = 0; i < sizeof(buf); i++) {
226		if (i % 4 == 0)
227			rnd = arc4random();
228		buf[i] = rnd;
229		rnd >>= 8;
230	}
231	RAND_add(buf, sizeof(buf), ENTROPY_NEEDED);
232	memset(buf, 0, sizeof(buf));
233
234	return 1;
235}
236#else /* !defined(__OpenBSD__) */
237int RAND_poll(void)
238{
239	unsigned long l;
240	pid_t curr_pid = getpid();
241#if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
242	unsigned char tmpbuf[ENTROPY_NEEDED];
243	int n = 0;
244#endif
245#ifdef DEVRANDOM
246	static const char *randomfiles[] = { DEVRANDOM };
247	struct stat randomstats[sizeof(randomfiles)/sizeof(randomfiles[0])];
248	int fd;
249	unsigned int i;
250#endif
251#ifdef DEVRANDOM_EGD
252	static const char *egdsockets[] = { DEVRANDOM_EGD, NULL };
253	const char **egdsocket = NULL;
254#endif
255
256#ifdef DEVRANDOM
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.  */
261
262	for (i = 0; (i < sizeof(randomfiles)/sizeof(randomfiles[0])) &&
263			(n < ENTROPY_NEEDED); i++)
264		{
265		if ((fd = open(randomfiles[i], O_RDONLY
266#ifdef O_NONBLOCK
267			|O_NONBLOCK
268#endif
269#ifdef O_BINARY
270			|O_BINARY
271#endif
272#ifdef O_NOCTTY /* If it happens to be a TTY (god forbid), do not make it
273		   our controlling tty */
274			|O_NOCTTY
275#endif
276			)) >= 0)
277			{
278			int usec = 10*1000; /* spend 10ms on each file */
279			int r;
280			unsigned int j;
281			struct stat *st=&randomstats[i];
282
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; }
286			for (j=0;j<i;j++)
287				{
288				if (randomstats[j].st_ino==st->st_ino &&
289				    randomstats[j].st_dev==st->st_dev)
290					break;
291				}
292			if (j<i)		{ close(fd); continue; }
293
294			do
295				{
296				int try_read = 0;
297
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 */
301				try_read = 1;
302
303#elif defined(OPENSSL_SYS_LINUX)
304				/* use poll() */
305				struct pollfd pset;
306
307				pset.fd = fd;
308				pset.events = POLLIN;
309				pset.revents = 0;
310
311				if (poll(&pset, 1, usec / 1000) < 0)
312					usec = 0;
313				else
314					try_read = (pset.revents & POLLIN) != 0;
315
316#else
317				/* use select() */
318				fd_set fset;
319				struct timeval t;
320
321				t.tv_sec = 0;
322				t.tv_usec = usec;
323
324				if (FD_SETSIZE > 0 && (unsigned)fd >= FD_SETSIZE)
325					{
326					/* can't use select, so just try to read once anyway */
327					try_read = 1;
328					}
329				else
330					{
331					FD_ZERO(&fset);
332					FD_SET(fd, &fset);
333
334					if (select(fd+1,&fset,NULL,NULL,&t) >= 0)
335						{
336						usec = t.tv_usec;
337						if (FD_ISSET(fd, &fset))
338							try_read = 1;
339						}
340					else
341						usec = 0;
342					}
343#endif
344
345				if (try_read)
346					{
347					r = read(fd,(unsigned char *)tmpbuf+n, ENTROPY_NEEDED-n);
348					if (r > 0)
349						n += r;
350#if defined(OPENSSL_SYS_BEOS_R5)
351					if (r == 0)
352						snooze(t.tv_usec);
353#endif
354					}
355				else
356					r = -1;
357
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
363				   time. */
364				if (usec == 10*1000)
365					usec = 0;
366				}
367			while ((r > 0 ||
368			       (errno == EINTR || errno == EAGAIN)) && usec != 0 && n < ENTROPY_NEEDED);
369
370			close(fd);
371			}
372		}
373#endif /* defined(DEVRANDOM) */
374
375#ifdef DEVRANDOM_EGD
376	/* Use an EGD socket to read entropy from an EGD or PRNGD entropy
377	 * collecting daemon. */
378
379	for (egdsocket = egdsockets; *egdsocket && n < ENTROPY_NEEDED; egdsocket++)
380		{
381		int r;
382
383		r = RAND_query_egd_bytes(*egdsocket, (unsigned char *)tmpbuf+n,
384					 ENTROPY_NEEDED-n);
385		if (r > 0)
386			n += r;
387		}
388#endif /* defined(DEVRANDOM_EGD) */
389
390#if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
391	if (n > 0)
392		{
393		RAND_add(tmpbuf,sizeof tmpbuf,(double)n);
394		OPENSSL_cleanse(tmpbuf,n);
395		}
396#endif
397
398	/* put in some default random data, we need more than just this */
399	l=curr_pid;
400	RAND_add(&l,sizeof(l),0.0);
401	l=getuid();
402	RAND_add(&l,sizeof(l),0.0);
403
404	l=time(NULL);
405	RAND_add(&l,sizeof(l),0.0);
406
407#if defined(OPENSSL_SYS_BEOS)
408	{
409	system_info sysInfo;
410	get_system_info(&sysInfo);
411	RAND_add(&sysInfo,sizeof(sysInfo),0);
412	}
413#endif
414
415#if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
416	return 1;
417#else
418	return 0;
419#endif
420}
421
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)) */
424
425
426#if defined(OPENSSL_SYS_VXWORKS)
427int RAND_poll(void)
428	{
429	return 0;
430	}
431#endif
432