1/* $NetBSD: rdate.c,v 1.22 2017/08/26 19:26:32 ginsbach 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 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28/* 29 * rdate.c: Set the date from the specified host 30 * 31 * Uses the rfc868 time protocol at socket 37. 32 * Time is returned as the number of seconds since 33 * midnight January 1st 1900. 34 */ 35#include <sys/cdefs.h> 36#ifndef lint 37__RCSID("$NetBSD: rdate.c,v 1.22 2017/08/26 19:26:32 ginsbach Exp $"); 38#endif /* lint */ 39 40#include <sys/types.h> 41#include <sys/socket.h> 42#include <sys/time.h> 43 44#include <netinet/in.h> 45 46#include <err.h> 47#include <netdb.h> 48#include <stdio.h> 49#include <stdlib.h> 50#include <string.h> 51#include <unistd.h> 52#include <util.h> 53 54/* seconds from midnight Jan 1900 - 1970 */ 55#define DIFFERENCE 2208988800ULL 56 57static void usage(void); 58 59static void 60usage(void) 61{ 62 (void) fprintf(stderr, "usage: %s [-46aps] host\n", getprogname()); 63 (void) fprintf(stderr, " -4: use IPv4 addresses only\n"); 64 (void) fprintf(stderr, " -6: use IPv6 addresses only\n"); 65 (void) fprintf(stderr, " -a: use adjtime instead of instant change\n"); 66 (void) fprintf(stderr, " -p: just print, don't set\n"); 67 (void) fprintf(stderr, " -s: just set, don't print\n"); 68} 69 70int 71main(int argc, char *argv[]) 72{ 73 int pr = 0, silent = 0, s; 74 int slidetime = 0; 75 int adjustment; 76 uint32_t data; 77 time_t tim; 78 char *hname; 79 const char *emsg = NULL; 80 struct addrinfo hints, *res, *res0; 81 int c; 82 int error; 83 int family = AF_UNSPEC; 84 85 adjustment = 0; 86 while ((c = getopt(argc, argv, "46aps")) != -1) 87 switch (c) { 88 case '4': 89 family = AF_INET; 90 break; 91 92 case '6': 93 family = AF_INET6; 94 break; 95 96 case 'a': 97 slidetime++; 98 break; 99 100 case 'p': 101 pr++; 102 break; 103 104 case 's': 105 silent++; 106 break; 107 108 default: 109 usage(); 110 return 1; 111 } 112 113 if (argc - 1 != optind) { 114 usage(); 115 return 1; 116 } 117 hname = argv[optind]; 118 119 memset(&hints, 0, sizeof (hints)); 120 hints.ai_family = family; 121 hints.ai_socktype = SOCK_STREAM; 122 hints.ai_flags = AI_CANONNAME; 123 error = getaddrinfo(hname, "time", &hints, &res0); 124 if (error) 125 errx(1, "%s: %s", gai_strerror(error), hname); 126 127 for (res = res0, s = -1; res != NULL; res = res->ai_next) { 128 s = socket(res->ai_family, res->ai_socktype, res->ai_protocol); 129 if (s < 0) { 130 emsg = "socket"; 131 continue; 132 } 133 134 if (connect(s, res->ai_addr, res->ai_addrlen)) { 135 close(s); 136 s = -1; 137 emsg = "connect"; 138 continue; 139 } 140 141 break; 142 } 143 if (s < 0) 144 err(1, "%s", emsg); 145 146 if (read(s, &data, sizeof(uint32_t)) != sizeof(uint32_t)) 147 err(1, "Could not read data"); 148 149 (void) close(s); 150 tim = ntohl(data) - DIFFERENCE; 151 152 if (!pr) { 153 struct timeval tv; 154 if (!slidetime) { 155 logwtmp("|", "date", ""); 156 tv.tv_sec = tim; 157 tv.tv_usec = 0; 158 if (settimeofday(&tv, NULL) == -1) 159 err(1, "Could not set time of day"); 160 logwtmp("{", "date", ""); 161 } else { 162 struct timeval tv_current; 163 if (gettimeofday(&tv_current, NULL) == -1) 164 err(1, "Could not get local time of day"); 165 adjustment = tv.tv_sec = tim - tv_current.tv_sec; 166 tv.tv_usec = 0; 167 if (adjtime(&tv, NULL) == -1) 168 err(1, "Could not adjust time of day"); 169 } 170 } 171 172 if (!silent) { 173 (void) fputs(ctime(&tim), stdout); 174 if (slidetime) 175 (void) fprintf(stdout, 176 "%s: adjust local clock by %d seconds\n", 177 getprogname(), adjustment); 178 } 179 return 0; 180} 181