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/*
* Copyright (c) 1993 Regents of the University of California.
* 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 acknowledgement:
* This product includes software developed by the Computer Systems
* Engineering Group at Lawrence Berkeley Laboratory.
* 4. Neither the name of the University nor of the Laboratory may be used
* to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS 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.
*/
/*
* LBL random number generator.
*
* Written by Steve McCanne & Chris Torek (mccanne@ee.lbl.gov,
* torek@ee.lbl.gov), November, 1992.
*
* This implementation is based on ``Two Fast Implementations of
* the "Minimal Standard" Random Number Generator", David G. Carta,
* Communications of the ACM, Jan 1990, Vol 33 No 1.
*/
#include "config_win32.h"
#include "config_unix.h"
#include "crypt_random.h"
static u_int32 randseed = 1;
void
lbl_srandom(u_int32 seed)
{
randseed = seed;
}
u_int32
lbl_random(void)
{
#if defined (Linux) || defined(FreeBSD)
/* I don't trust the LBL random number generator, so if */
/* we're on Linux we now use the random number generator */
/* in the kernel which is cryptographically strong. [csp] */
int fd, res, l;
fd = open("/dev/urandom", O_RDONLY);
if (fd == -1) {
perror("Cannot open random sequence generator");
abort();
}
l = read(fd, &res, sizeof(res));
if (l != sizeof(res)) {
perror("Cannot read random data");
abort();
}
close(fd);
return res;
#else
register u_int32 x = randseed;
register u_int32 hi, lo, t;
hi = x / 127773;
lo = x % 127773;
t = 16807 * lo - 2836 * hi;
if (t <= 0)
t += 0x7fffffff;
randseed = t;
return (t);
#endif
}
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