/* * magic.c - PPP Magic Number routines. * * Copyright (c) 1989 Carnegie Mellon University. * All rights reserved. * * Redistribution and use in source and binary forms are permitted * provided that the above copyright notice and this paragraph are * duplicated in all such forms and that any documentation, * advertising materials, and other materials related to such * distribution and use acknowledge that the software was developed * by Carnegie Mellon University. The name of the * University may not be used to endorse or promote products derived * from this software without specific prior written permission. * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. * * $FreeBSD: src/usr.sbin/pppd/magic.c,v 1.8 1999/08/28 01:19:05 peter Exp $ * $DragonFly: src/usr.sbin/pppd/magic.c,v 1.4 2005/11/24 23:42:54 swildner Exp $ */ #include #include #include #include #include "pppd.h" #include "magic.h" extern long mrand48(void); extern void srand48(long); /* * magic_init - Initialize the magic number generator. * * Attempts to compute a random number seed which will not repeat. * The current method uses the current hostid, current process ID * and current time, currently. */ void magic_init(void) { long seed; struct timeval t; gettimeofday(&t, NULL); seed = get_host_seed() ^ t.tv_sec ^ t.tv_usec ^ getpid(); srand48(seed); } /* * magic - Returns the next magic number. */ u_int32_t magic(void) { return (u_int32_t) mrand48(); } #ifdef NO_DRAND48 /* * Substitute procedures for those systems which don't have * drand48 et al. */ double drand48(void) { return (double)random() / (double)0x7fffffffL; /* 2**31-1 */ } long mrand48(void) { return random(); } void srand48(long seedval) { srandom((int)seedval); } #endif