1 /* $NetBSD: magic.c,v 1.6 2025/01/08 19:59:39 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 __RCSID("$NetBSD: magic.c,v 1.6 2025/01/08 19:59:39 christos Exp $"); 47 48 #ifdef HAVE_CONFIG_H 49 #include "config.h" 50 #endif 51 52 #include <stdio.h> 53 #include <stdlib.h> 54 #include <unistd.h> 55 #include <sys/types.h> 56 #include <sys/time.h> 57 58 #include "pppd-private.h" 59 #include "magic.h" 60 61 62 extern long mrand48 (void); 63 extern void srand48 (long); 64 65 /* 66 * magic_init - Initialize the magic number generator. 67 * 68 * Attempts to compute a random number seed which will not repeat. 69 * The current method uses the current hostid, current process ID 70 * and current time, currently. 71 */ 72 void 73 magic_init(void) 74 { 75 long seed; 76 struct timeval t; 77 78 gettimeofday(&t, NULL); 79 seed = get_host_seed() ^ t.tv_sec ^ t.tv_usec ^ getpid(); 80 srand48(seed); 81 } 82 83 /* 84 * magic - Returns the next magic number. 85 */ 86 u_int32_t 87 magic(void) 88 { 89 return (u_int32_t) mrand48(); 90 } 91 92 /* 93 * random_bytes - Fill a buffer with random bytes. 94 */ 95 void 96 random_bytes(unsigned char *buf, int len) 97 { 98 int i; 99 100 for (i = 0; i < len; ++i) 101 buf[i] = mrand48() >> 24; 102 } 103 104 #ifdef NO_DRAND48 105 /* 106 * Substitute procedures for those systems which don't have 107 * drand48 et al. 108 */ 109 110 double 111 drand48(void) 112 { 113 return (double)random() / (double)0x7fffffffL; /* 2**31-1 */ 114 } 115 116 long 117 mrand48(void) 118 { 119 return random(); 120 } 121 122 void 123 srand48(long seedval) 124 { 125 srandom((int)seedval); 126 } 127 128 #endif 129