openssl/crypto/rand/rand_unix.c
2006-06-30 08:14:50 +00:00

330 lines
11 KiB
C

/* crypto/rand/rand_unix.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
/* ====================================================================
* Copyright (c) 1998-2006 The OpenSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* openssl-core@openssl.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com).
*
*/
#include <stdio.h>
#define USE_SOCKETS
#include "e_os.h"
#include "cryptlib.h"
#include <openssl/rand.h>
#include "rand_lcl.h"
#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))
#include <sys/types.h>
#include <sys/time.h>
#include <sys/times.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <time.h>
#if defined(OPENSSL_SYS_LINUX) /* should actually be available virtually everywhere */
# include <poll.h>
#endif
#include <limits.h>
#ifndef FD_SETSIZE
# define FD_SETSIZE (8*sizeof(fd_set))
#endif
#ifdef __OpenBSD__
int RAND_poll(void)
{
u_int32_t rnd = 0, i;
unsigned char buf[ENTROPY_NEEDED];
for (i = 0; i < sizeof(buf); i++) {
if (i % 4 == 0)
rnd = arc4random();
buf[i] = rnd;
rnd >>= 8;
}
RAND_add(buf, sizeof(buf), ENTROPY_NEEDED);
memset(buf, 0, sizeof(buf));
return 1;
}
#else /* !defined(__OpenBSD__) */
int RAND_poll(void)
{
unsigned long l;
pid_t curr_pid = getpid();
#if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
unsigned char tmpbuf[ENTROPY_NEEDED];
int n = 0;
#endif
#ifdef DEVRANDOM
static const char *randomfiles[] = { DEVRANDOM };
struct stat randomstats[sizeof(randomfiles)/sizeof(randomfiles[0])];
int fd;
size_t i;
#endif
#ifdef DEVRANDOM_EGD
static const char *egdsockets[] = { DEVRANDOM_EGD, NULL };
const char **egdsocket = NULL;
#endif
#ifdef DEVRANDOM
memset(randomstats,0,sizeof(randomstats));
/* Use a random entropy pool device. Linux, FreeBSD and OpenBSD
* have this. Use /dev/urandom if you can as /dev/random may block
* if it runs out of random entries. */
for (i=0; i<sizeof(randomfiles)/sizeof(randomfiles[0]) && n < ENTROPY_NEEDED; i++)
{
if ((fd = open(randomfiles[i], O_RDONLY
#ifdef O_NONBLOCK
|O_NONBLOCK
#endif
#ifdef O_BINARY
|O_BINARY
#endif
#ifdef O_NOCTTY /* If it happens to be a TTY (god forbid), do not make it
our controlling tty */
|O_NOCTTY
#endif
)) >= 0)
{
int usec = 10*1000; /* spend 10ms on each file */
int r;
size_t j;
struct stat *st=&randomstats[i];
/* Avoid using same input... Used to be O_NOFOLLOW
* above, but it's not universally appropriate... */
if (fstat(fd,st) != 0) { close(fd); continue; }
for (j=0;j<i;j++)
{
if (randomstats[j].st_ino==st->st_ino &&
randomstats[j].st_dev==st->st_dev)
break;
}
if (j<i) { close(fd); continue; }
do
{
int try_read = 0;
#if defined(OPENSSL_SYS_LINUX)
/* use poll() */
struct pollfd pset;
pset.fd = fd;
pset.events = POLLIN;
pset.revents = 0;
if (poll(&pset, 1, usec / 1000) < 0)
usec = 0;
else
try_read = (pset.revents & POLLIN) != 0;
#else
/* use select() */
fd_set fset;
struct timeval t;
t.tv_sec = 0;
t.tv_usec = usec;
if (FD_SETSIZE > 0 && fd >= FD_SETSIZE)
{
/* can't use select, so just try to read once anyway */
try_read = 1;
}
else
{
FD_ZERO(&fset);
FD_SET(fd, &fset);
if (select(fd+1,&fset,NULL,NULL,&t) >= 0)
{
usec = t.tv_usec;
if (FD_ISSET(fd, &fset))
try_read = 1;
}
else
usec = 0;
}
#endif
if (try_read)
{
r = read(fd,(unsigned char *)tmpbuf+n, ENTROPY_NEEDED-n);
if (r > 0)
n += r;
}
else
r = -1;
/* Some Unixen will update t in select(), some
won't. For those who won't, or if we
didn't use select() in the first place,
give up here, otherwise, we will do
this once again for the remaining
time. */
if (usec == 10*1000)
usec = 0;
}
while ((r > 0 ||
(errno == EINTR || errno == EAGAIN)) && usec != 0 && n < ENTROPY_NEEDED);
close(fd);
}
}
#endif /* defined(DEVRANDOM) */
#ifdef DEVRANDOM_EGD
/* Use an EGD socket to read entropy from an EGD or PRNGD entropy
* collecting daemon. */
for (egdsocket = egdsockets; *egdsocket && n < ENTROPY_NEEDED; egdsocket++)
{
int r;
r = RAND_query_egd_bytes(*egdsocket, (unsigned char *)tmpbuf+n,
ENTROPY_NEEDED-n);
if (r > 0)
n += r;
}
#endif /* defined(DEVRANDOM_EGD) */
#if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
if (n > 0)
{
RAND_add(tmpbuf,sizeof tmpbuf,(double)n);
OPENSSL_cleanse(tmpbuf,n);
}
#endif
/* put in some default random data, we need more than just this */
l=curr_pid;
RAND_add(&l,sizeof(l),0.0);
l=getuid();
RAND_add(&l,sizeof(l),0.0);
l=time(NULL);
RAND_add(&l,sizeof(l),0.0);
#if defined(DEVRANDOM) || defined(DEVRANDOM_EGD)
return 1;
#else
return 0;
#endif
}
#endif /* defined(__OpenBSD__) */
#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)) */
#if defined(OPENSSL_SYS_VXWORKS)
int RAND_poll(void)
{
return 0;
}
#endif