1 /* $NetBSD: magic.c,v 1.4 2014/10/25 21:11:37 christos Exp $ */ 2 3 /* 4 * magic.c - PPP Magic Number routines. 5 * 6 * Copyright (c) 1984-2000 Carnegie Mellon University. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 20 * 3. The name "Carnegie Mellon University" must not be used to 21 * endorse or promote products derived from this software without 22 * prior written permission. For permission or any legal 23 * details, please contact 24 * Office of Technology Transfer 25 * Carnegie Mellon University 26 * 5000 Forbes Avenue 27 * Pittsburgh, PA 15213-3890 28 * (412) 268-4387, fax: (412) 268-7395 29 * tech-transfer@andrew.cmu.edu 30 * 31 * 4. Redistributions of any form whatsoever must retain the following 32 * acknowledgment: 33 * "This product includes software developed by Computing Services 34 * at Carnegie Mellon University (http://www.cmu.edu/computing/)." 35 * 36 * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO 37 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 38 * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE 39 * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 40 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN 41 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING 42 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 43 */ 44 45 #include <sys/cdefs.h> 46 #if 0 47 #define RCSID "Id: magic.c,v 1.11 2003/06/11 23:56:26 paulus Exp " 48 static const char rcsid[] = RCSID; 49 #else 50 __RCSID("$NetBSD: magic.c,v 1.4 2014/10/25 21:11:37 christos Exp $"); 51 #endif 52 53 #include <stdio.h> 54 #include <stdlib.h> 55 #include <unistd.h> 56 #include <sys/types.h> 57 #include <sys/time.h> 58 59 #include "pppd.h" 60 #include "magic.h" 61 62 63 extern long mrand48 __P((void)); 64 extern void srand48 __P((long)); 65 66 /* 67 * magic_init - Initialize the magic number generator. 68 * 69 * Attempts to compute a random number seed which will not repeat. 70 * The current method uses the current hostid, current process ID 71 * and current time, currently. 72 */ 73 void 74 magic_init() 75 { 76 long seed; 77 struct timeval t; 78 79 gettimeofday(&t, NULL); 80 seed = get_host_seed() ^ t.tv_sec ^ t.tv_usec ^ getpid(); 81 srand48(seed); 82 } 83 84 /* 85 * magic - Returns the next magic number. 86 */ 87 u_int32_t 88 magic() 89 { 90 return (u_int32_t) mrand48(); 91 } 92 93 /* 94 * random_bytes - Fill a buffer with random bytes. 95 */ 96 void 97 random_bytes(unsigned char *buf, int len) 98 { 99 int i; 100 101 for (i = 0; i < len; ++i) 102 buf[i] = mrand48() >> 24; 103 } 104 105 #ifdef NO_DRAND48 106 /* 107 * Substitute procedures for those systems which don't have 108 * drand48 et al. 109 */ 110 111 double 112 drand48() 113 { 114 return (double)random() / (double)0x7fffffffL; /* 2**31-1 */ 115 } 116 117 long 118 mrand48() 119 { 120 return random(); 121 } 122 123 void 124 srand48(seedval) 125 long seedval; 126 { 127 srandom((int)seedval); 128 } 129 130 #endif 131