1 /* $NetBSD: rdate.c,v 1.14 2002/07/14 01:01:10 wiz Exp $ */ 2 3 /* 4 * Copyright (c) 1994 Christos Zoulas 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Christos Zoulas. 18 * 4. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 /* 34 * rdate.c: Set the date from the specified host 35 * 36 * Uses the rfc868 time protocol at socket 37. 37 * Time is returned as the number of seconds since 38 * midnight January 1st 1900. 39 */ 40 #include <sys/cdefs.h> 41 #ifndef lint 42 __RCSID("$NetBSD: rdate.c,v 1.14 2002/07/14 01:01:10 wiz Exp $"); 43 #endif /* lint */ 44 45 #include <sys/types.h> 46 #include <sys/socket.h> 47 #include <sys/time.h> 48 49 #include <netinet/in.h> 50 51 #include <ctype.h> 52 #include <err.h> 53 #include <netdb.h> 54 #include <stdio.h> 55 #include <stdlib.h> 56 #include <string.h> 57 #include <unistd.h> 58 #include <util.h> 59 60 /* seconds from midnight Jan 1900 - 1970 */ 61 #define DIFFERENCE 2208988800UL 62 63 int main(int, char **); 64 static void usage(void); 65 66 static void 67 usage(void) 68 { 69 (void) fprintf(stderr, "Usage: %s [-psa] host\n", getprogname()); 70 (void) fprintf(stderr, " -p: just print, don't set\n"); 71 (void) fprintf(stderr, " -s: just set, don't print\n"); 72 (void) fprintf(stderr, " -a: use adjtime instead of instant change\n"); 73 } 74 75 int 76 main(int argc, char *argv[]) 77 { 78 int pr = 0, silent = 0, s; 79 int slidetime = 0; 80 int adjustment; 81 time_t tim; 82 char *hname, *emsg; 83 struct addrinfo hints, *res, *res0; 84 int c; 85 int error; 86 87 adjustment = 0; 88 while ((c = getopt(argc, argv, "psa")) != -1) 89 switch (c) { 90 case 'p': 91 pr++; 92 break; 93 94 case 's': 95 silent++; 96 break; 97 98 case 'a': 99 slidetime++; 100 break; 101 102 default: 103 usage(); 104 return 1; 105 } 106 107 if (argc - 1 != optind) { 108 usage(); 109 return 1; 110 } 111 hname = argv[optind]; 112 113 memset(&hints, 0, sizeof (hints)); 114 hints.ai_family = PF_UNSPEC; 115 hints.ai_socktype = SOCK_STREAM; 116 hints.ai_flags = AI_CANONNAME; 117 error = getaddrinfo(hname, "time", &hints, &res0); 118 if (error) 119 errx(1, "%s: %s", gai_strerror(error), hname); 120 121 for (res = res0, s = -1; res != NULL; res = res->ai_next) { 122 s = socket(res->ai_family, res->ai_socktype, res->ai_protocol); 123 if (s < 0) { 124 emsg = "socket"; 125 continue; 126 } 127 128 if (connect(s, res->ai_addr, res->ai_addrlen)) { 129 close(s); 130 s = -1; 131 emsg = "connect"; 132 continue; 133 } 134 135 break; 136 } 137 if (s < 0) 138 err(1, "%s", emsg); 139 140 if (read(s, &tim, sizeof(time_t)) != sizeof(time_t)) 141 err(1, "Could not read data"); 142 143 (void) close(s); 144 tim = ntohl(tim) - DIFFERENCE; 145 146 if (!pr) { 147 struct timeval tv; 148 if (!slidetime) { 149 logwtmp("|", "date", ""); 150 tv.tv_sec = tim; 151 tv.tv_usec = 0; 152 if (settimeofday(&tv, NULL) == -1) 153 err(1, "Could not set time of day"); 154 logwtmp("{", "date", ""); 155 } else { 156 struct timeval tv_current; 157 if (gettimeofday(&tv_current, NULL) == -1) 158 err(1, "Could not get local time of day"); 159 adjustment = tv.tv_sec = tim - tv_current.tv_sec; 160 tv.tv_usec = 0; 161 if (adjtime(&tv, NULL) == -1) 162 err(1, "Could not adjust time of day"); 163 } 164 } 165 166 if (!silent) { 167 (void) fputs(ctime(&tim), stdout); 168 if (slidetime) 169 (void) fprintf(stdout, 170 "%s: adjust local clock by %d seconds\n", 171 getprogname(), adjustment); 172 } 173 return 0; 174 } 175