rand_unix.c revision 109998
1109998Smarkm/* crypto/rand/rand_unix.c */
2109998Smarkm/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3109998Smarkm * All rights reserved.
4109998Smarkm *
5109998Smarkm * This package is an SSL implementation written
6109998Smarkm * by Eric Young (eay@cryptsoft.com).
7109998Smarkm * The implementation was written so as to conform with Netscapes SSL.
8109998Smarkm *
9109998Smarkm * This library is free for commercial and non-commercial use as long as
10109998Smarkm * the following conditions are aheared to.  The following conditions
11109998Smarkm * apply to all code found in this distribution, be it the RC4, RSA,
12109998Smarkm * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13109998Smarkm * included with this distribution is covered by the same copyright terms
14109998Smarkm * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15109998Smarkm *
16109998Smarkm * Copyright remains Eric Young's, and as such any Copyright notices in
17109998Smarkm * the code are not to be removed.
18109998Smarkm * If this package is used in a product, Eric Young should be given attribution
19109998Smarkm * as the author of the parts of the library used.
20109998Smarkm * This can be in the form of a textual message at program startup or
21109998Smarkm * in documentation (online or textual) provided with the package.
22109998Smarkm *
23109998Smarkm * Redistribution and use in source and binary forms, with or without
24109998Smarkm * modification, are permitted provided that the following conditions
25109998Smarkm * are met:
26109998Smarkm * 1. Redistributions of source code must retain the copyright
27109998Smarkm *    notice, this list of conditions and the following disclaimer.
28109998Smarkm * 2. Redistributions in binary form must reproduce the above copyright
29109998Smarkm *    notice, this list of conditions and the following disclaimer in the
30109998Smarkm *    documentation and/or other materials provided with the distribution.
31109998Smarkm * 3. All advertising materials mentioning features or use of this software
32109998Smarkm *    must display the following acknowledgement:
33109998Smarkm *    "This product includes cryptographic software written by
34109998Smarkm *     Eric Young (eay@cryptsoft.com)"
35109998Smarkm *    The word 'cryptographic' can be left out if the rouines from the library
36109998Smarkm *    being used are not cryptographic related :-).
37109998Smarkm * 4. If you include any Windows specific code (or a derivative thereof) from
38109998Smarkm *    the apps directory (application code) you must include an acknowledgement:
39109998Smarkm *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40109998Smarkm *
41109998Smarkm * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42109998Smarkm * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43109998Smarkm * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44109998Smarkm * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45109998Smarkm * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46109998Smarkm * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47109998Smarkm * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48109998Smarkm * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49109998Smarkm * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50109998Smarkm * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51109998Smarkm * SUCH DAMAGE.
52109998Smarkm *
53109998Smarkm * The licence and distribution terms for any publically available version or
54109998Smarkm * derivative of this code cannot be changed.  i.e. this code cannot simply be
55109998Smarkm * copied and put under another distribution licence
56109998Smarkm * [including the GNU Public Licence.]
57109998Smarkm */
58109998Smarkm/* ====================================================================
59109998Smarkm * Copyright (c) 1998-2000 The OpenSSL Project.  All rights reserved.
60109998Smarkm *
61109998Smarkm * Redistribution and use in source and binary forms, with or without
62109998Smarkm * modification, are permitted provided that the following conditions
63109998Smarkm * are met:
64109998Smarkm *
65109998Smarkm * 1. Redistributions of source code must retain the above copyright
66109998Smarkm *    notice, this list of conditions and the following disclaimer.
67109998Smarkm *
68109998Smarkm * 2. Redistributions in binary form must reproduce the above copyright
69109998Smarkm *    notice, this list of conditions and the following disclaimer in
70109998Smarkm *    the documentation and/or other materials provided with the
71109998Smarkm *    distribution.
72109998Smarkm *
73109998Smarkm * 3. All advertising materials mentioning features or use of this
74109998Smarkm *    software must display the following acknowledgment:
75109998Smarkm *    "This product includes software developed by the OpenSSL Project
76109998Smarkm *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
77109998Smarkm *
78109998Smarkm * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
79109998Smarkm *    endorse or promote products derived from this software without
80109998Smarkm *    prior written permission. For written permission, please contact
81109998Smarkm *    openssl-core@openssl.org.
82109998Smarkm *
83109998Smarkm * 5. Products derived from this software may not be called "OpenSSL"
84109998Smarkm *    nor may "OpenSSL" appear in their names without prior written
85109998Smarkm *    permission of the OpenSSL Project.
86109998Smarkm *
87109998Smarkm * 6. Redistributions of any form whatsoever must retain the following
88109998Smarkm *    acknowledgment:
89109998Smarkm *    "This product includes software developed by the OpenSSL Project
90109998Smarkm *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
91109998Smarkm *
92109998Smarkm * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
93109998Smarkm * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94109998Smarkm * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
95109998Smarkm * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
96109998Smarkm * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
97109998Smarkm * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
98109998Smarkm * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
99109998Smarkm * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100109998Smarkm * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
101109998Smarkm * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
102109998Smarkm * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
103109998Smarkm * OF THE POSSIBILITY OF SUCH DAMAGE.
104109998Smarkm * ====================================================================
105109998Smarkm *
106109998Smarkm * This product includes cryptographic software written by Eric Young
107109998Smarkm * (eay@cryptsoft.com).  This product includes software written by Tim
108109998Smarkm * Hudson (tjh@cryptsoft.com).
109109998Smarkm *
110109998Smarkm */
111109998Smarkm
112109998Smarkm#define USE_SOCKETS
113109998Smarkm#include "e_os.h"
114109998Smarkm#include "cryptlib.h"
115109998Smarkm#include <openssl/rand.h>
116109998Smarkm#include "rand_lcl.h"
117109998Smarkm
118109998Smarkm#if !(defined(OPENSSL_SYS_WINDOWS) || defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VMS) || defined(OPENSSL_SYS_OS2) || defined(OPENSSL_SYS_VXWORKS))
119109998Smarkm
120109998Smarkm#include <sys/types.h>
121109998Smarkm#include <sys/time.h>
122109998Smarkm#include <sys/times.h>
123109998Smarkm#include <fcntl.h>
124109998Smarkm#include <unistd.h>
125109998Smarkm#include <time.h>
126109998Smarkm
127109998Smarkmint RAND_poll(void)
128109998Smarkm{
129109998Smarkm	unsigned long l;
130109998Smarkm	pid_t curr_pid = getpid();
131109998Smarkm#if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
132109998Smarkm	unsigned char tmpbuf[ENTROPY_NEEDED];
133109998Smarkm	int n = 0;
134109998Smarkm#endif
135109998Smarkm#ifdef DEVRANDOM
136109998Smarkm	static const char *randomfiles[] = { DEVRANDOM, NULL };
137109998Smarkm	const char **randomfile = NULL;
138109998Smarkm	int fd;
139109998Smarkm#endif
140109998Smarkm#ifdef DEVRANDOM_EGD
141109998Smarkm	static const char *egdsockets[] = { DEVRANDOM_EGD, NULL };
142109998Smarkm	const char **egdsocket = NULL;
143109998Smarkm#endif
144109998Smarkm
145109998Smarkm#ifdef DEVRANDOM
146109998Smarkm	/* Use a random entropy pool device. Linux, FreeBSD and OpenBSD
147109998Smarkm	 * have this. Use /dev/urandom if you can as /dev/random may block
148109998Smarkm	 * if it runs out of random entries.  */
149109998Smarkm
150109998Smarkm	for (randomfile = randomfiles; *randomfile && n < ENTROPY_NEEDED; randomfile++)
151109998Smarkm		{
152109998Smarkm		if ((fd = open(*randomfile, O_RDONLY|O_NONBLOCK
153109998Smarkm#ifdef O_NOCTTY /* If it happens to be a TTY (god forbid), do not make it
154109998Smarkm		   our controlling tty */
155109998Smarkm			|O_NOCTTY
156109998Smarkm#endif
157109998Smarkm#ifdef O_NOFOLLOW /* Fail if the file is a symbolic link */
158109998Smarkm			|O_NOFOLLOW
159109998Smarkm#endif
160109998Smarkm			)) >= 0)
161109998Smarkm			{
162109998Smarkm			struct timeval t = { 0, 10*1000 }; /* Spend 10ms on
163109998Smarkm							      each file. */
164109998Smarkm			int r;
165109998Smarkm			fd_set fset;
166109998Smarkm
167109998Smarkm			do
168109998Smarkm				{
169109998Smarkm				FD_ZERO(&fset);
170109998Smarkm				FD_SET(fd, &fset);
171109998Smarkm				r = -1;
172109998Smarkm
173109998Smarkm				if (select(fd+1,&fset,NULL,NULL,&t) < 0)
174109998Smarkm					t.tv_usec=0;
175109998Smarkm				else if (FD_ISSET(fd, &fset))
176109998Smarkm					{
177109998Smarkm					r=read(fd,(unsigned char *)tmpbuf+n,
178109998Smarkm					       ENTROPY_NEEDED-n);
179109998Smarkm					if (r > 0)
180109998Smarkm						n += r;
181109998Smarkm					}
182109998Smarkm
183109998Smarkm				/* Some Unixen will update t, some
184109998Smarkm				   won't.  For those who won't, give
185109998Smarkm				   up here, otherwise, we will do
186109998Smarkm				   this once again for the remaining
187109998Smarkm				   time. */
188109998Smarkm				if (t.tv_usec == 10*1000)
189109998Smarkm					t.tv_usec=0;
190109998Smarkm				}
191109998Smarkm			while ((r > 0 || (errno == EINTR || errno == EAGAIN))
192109998Smarkm				&& t.tv_usec != 0 && n < ENTROPY_NEEDED);
193109998Smarkm
194109998Smarkm			close(fd);
195109998Smarkm			}
196109998Smarkm		}
197109998Smarkm#endif
198109998Smarkm
199109998Smarkm#ifdef DEVRANDOM_EGD
200109998Smarkm	/* Use an EGD socket to read entropy from an EGD or PRNGD entropy
201109998Smarkm	 * collecting daemon. */
202109998Smarkm
203109998Smarkm	for (egdsocket = egdsockets; *egdsocket && n < ENTROPY_NEEDED; egdsocket++)
204109998Smarkm		{
205109998Smarkm		int r;
206109998Smarkm
207109998Smarkm		r = RAND_query_egd_bytes(*egdsocket, (unsigned char *)tmpbuf+n,
208109998Smarkm					 ENTROPY_NEEDED-n);
209109998Smarkm		if (r > 0)
210109998Smarkm			n += r;
211109998Smarkm		}
212109998Smarkm#endif
213109998Smarkm
214109998Smarkm#if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
215109998Smarkm	if (n > 0)
216109998Smarkm		{
217109998Smarkm		RAND_add(tmpbuf,sizeof tmpbuf,n);
218109998Smarkm		OPENSSL_cleanse(tmpbuf,n);
219109998Smarkm		}
220109998Smarkm#endif
221109998Smarkm
222109998Smarkm	/* put in some default random data, we need more than just this */
223109998Smarkm	l=curr_pid;
224109998Smarkm	RAND_add(&l,sizeof(l),0);
225109998Smarkm	l=getuid();
226109998Smarkm	RAND_add(&l,sizeof(l),0);
227109998Smarkm
228109998Smarkm	l=time(NULL);
229109998Smarkm	RAND_add(&l,sizeof(l),0);
230109998Smarkm
231109998Smarkm#if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
232109998Smarkm	return 1;
233109998Smarkm#else
234109998Smarkm	return 0;
235109998Smarkm#endif
236109998Smarkm}
237109998Smarkm
238109998Smarkm#endif
239109998Smarkm
240109998Smarkm#if defined(OPENSSL_SYS_VXWORKS)
241109998Smarkmint RAND_poll(void)
242109998Smarkm{
243109998Smarkm    return 0;
244109998Smarkm}
245109998Smarkm#endif
246