1 /* $NetBSD: rdate.c,v 1.19 2009/10/21 01:07:47 snj 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 1.19 2009/10/21 01:07:47 snj 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 57 int main(int, char **); 58 static void usage(void); 59 60 static void 61 usage(void) 62 { 63 (void) fprintf(stderr, "usage: %s [-psa] host\n", getprogname()); 64 (void) fprintf(stderr, " -p: just print, don't set\n"); 65 (void) fprintf(stderr, " -s: just set, don't print\n"); 66 (void) fprintf(stderr, " -a: use adjtime instead of instant change\n"); 67 } 68 69 int 70 main(int argc, char *argv[]) 71 { 72 int pr = 0, silent = 0, s; 73 int slidetime = 0; 74 int adjustment; 75 uint32_t data; 76 time_t tim; 77 char *hname; 78 const char *emsg = NULL; 79 struct addrinfo hints, *res, *res0; 80 int c; 81 int error; 82 83 adjustment = 0; 84 while ((c = getopt(argc, argv, "psa")) != -1) 85 switch (c) { 86 case 'p': 87 pr++; 88 break; 89 90 case 's': 91 silent++; 92 break; 93 94 case 'a': 95 slidetime++; 96 break; 97 98 default: 99 usage(); 100 return 1; 101 } 102 103 if (argc - 1 != optind) { 104 usage(); 105 return 1; 106 } 107 hname = argv[optind]; 108 109 memset(&hints, 0, sizeof (hints)); 110 hints.ai_family = PF_UNSPEC; 111 hints.ai_socktype = SOCK_STREAM; 112 hints.ai_flags = AI_CANONNAME; 113 error = getaddrinfo(hname, "time", &hints, &res0); 114 if (error) 115 errx(1, "%s: %s", gai_strerror(error), hname); 116 117 for (res = res0, s = -1; res != NULL; res = res->ai_next) { 118 s = socket(res->ai_family, res->ai_socktype, res->ai_protocol); 119 if (s < 0) { 120 emsg = "socket"; 121 continue; 122 } 123 124 if (connect(s, res->ai_addr, res->ai_addrlen)) { 125 close(s); 126 s = -1; 127 emsg = "connect"; 128 continue; 129 } 130 131 break; 132 } 133 if (s < 0) 134 err(1, "%s", emsg); 135 136 if (read(s, &data, sizeof(uint32_t)) != sizeof(uint32_t)) 137 err(1, "Could not read data"); 138 139 (void) close(s); 140 tim = ntohl(data) - DIFFERENCE; 141 142 if (!pr) { 143 struct timeval tv; 144 if (!slidetime) { 145 logwtmp("|", "date", ""); 146 tv.tv_sec = tim; 147 tv.tv_usec = 0; 148 if (settimeofday(&tv, NULL) == -1) 149 err(1, "Could not set time of day"); 150 logwtmp("{", "date", ""); 151 } else { 152 struct timeval tv_current; 153 if (gettimeofday(&tv_current, NULL) == -1) 154 err(1, "Could not get local time of day"); 155 adjustment = tv.tv_sec = tim - tv_current.tv_sec; 156 tv.tv_usec = 0; 157 if (adjtime(&tv, NULL) == -1) 158 err(1, "Could not adjust time of day"); 159 } 160 } 161 162 if (!silent) { 163 (void) fputs(ctime(&tim), stdout); 164 if (slidetime) 165 (void) fprintf(stdout, 166 "%s: adjust local clock by %d seconds\n", 167 getprogname(), adjustment); 168 } 169 return 0; 170 } 171