1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
28 /* All Rights Reserved */
29
30 /*
31 * University Copyright- Copyright (c) 1982, 1986, 1988
32 * The Regents of the University of California
33 * All Rights Reserved
34 *
35 * University Acknowledgment- Portions of this document are derived from
36 * software developed by the University of California, Berkeley, and its
37 * contributors.
38 */
39
40 /*
41 * rdate - get date from remote machine
42 *
43 * sets time, obtaining value from host
44 * on the tcp/time socket.
45 */
46
47 #include <signal.h>
48 #include <sys/types.h>
49 #include <sys/time.h>
50 #include <sys/socket.h>
51 #include <netinet/tcp.h>
52 #include <strings.h>
53 #include <unistd.h>
54 #include <stdlib.h>
55 #include <netdb.h>
56 #include <stdio.h>
57
58 /*
59 * The timeserver returns with time of day in seconds since
60 * Jan 1, 1900. We must subtract 86400(365*70 + 17) to get time
61 * since Jan 1, 1970, which is what get/settimeofday uses.
62 */
63
64 #define TOFFSET ((unsigned int)86400*(365*70 + 17))
65
66 /*
67 * Before setting the system time, the value returned by the
68 * timeserver is checked for plausibility. If the returned date
69 * is before the time this program was written it cannot be
70 * correct.
71 */
72
73 #define WRITTEN 440199955 /* 22:45:55 13/Dec/1983 */
74 #define SECONDS_TO_MS 1000
75
76 static void timeout(int);
77
78 int
main(int argc,char ** argv)79 main(int argc, char **argv)
80 {
81 int s, i;
82 uint32_t time;
83 struct timeval timestruct;
84 unsigned int connect_timeout;
85 /* number of seconds to wait for something to happen. */
86 unsigned int rdate_timeout = 30; /* seconds */
87 struct addrinfo hints;
88 struct addrinfo *res;
89 int rc;
90
91 if (argc != 2) {
92 (void) fputs("usage: rdate host\n", stderr);
93 exit(EXIT_FAILURE);
94 }
95
96 (void) memset(&hints, 0, sizeof (hints));
97 hints.ai_protocol = IPPROTO_TCP;
98 res = NULL;
99
100 /*
101 * getaddrinfo() may take a long time, because it can involve
102 * NIS, DNS, or LDAP lookups. Set an alarm timer. Note that this
103 * may still fail, depending on how SIGALRM is handled by the
104 * functions invoked by getaddrinfo().
105 */
106
107 (void) signal(SIGALRM, timeout);
108 (void) alarm(rdate_timeout);
109
110 /*
111 * Note: memory not freed due to short lifetime of program.
112 */
113
114 rc = getaddrinfo(argv[1], "time", &hints, &res);
115 (void) alarm(0);
116
117 if (rc != 0) {
118 (void) fprintf(stderr, "Host name %s not found: %s\n", argv[1],
119 gai_strerror(rc));
120 exit(EXIT_FAILURE);
121 }
122
123 connect_timeout = rdate_timeout * SECONDS_TO_MS;
124 for (; res != NULL; res = res->ai_next) {
125 s = socket(res->ai_addr->sa_family, res->ai_socktype,
126 res->ai_protocol);
127 if (s < 0) {
128 perror("rdate: socket");
129 exit(EXIT_FAILURE);
130 }
131
132 if (setsockopt(s, IPPROTO_TCP, TCP_CONN_ABORT_THRESHOLD,
133 (char *)&connect_timeout, sizeof (connect_timeout)) == -1) {
134 perror("setsockopt TCP_CONN_ABORT_THRESHOLD");
135 }
136
137 if (connect(s, res->ai_addr, res->ai_addrlen) >= 0)
138 break;
139
140 if (res->ai_next == NULL) {
141 perror("rdate: connect");
142 (void) close(s);
143 exit(EXIT_FAILURE);
144 }
145
146 (void) close(s);
147 }
148
149 (void) alarm(rdate_timeout);
150 if (read(s, (char *)&time, sizeof (time)) != sizeof (time)) {
151 perror("rdate: read");
152 exit(EXIT_FAILURE);
153 }
154 (void) alarm(0);
155
156 time = ntohl(time) - TOFFSET;
157 /* date must be later than when program was written */
158 if (time < WRITTEN) {
159 (void) fprintf(stderr, "didn't get plausible time from %s\n",
160 argv[1]);
161 exit(EXIT_FAILURE);
162 }
163 timestruct.tv_usec = 0;
164 timestruct.tv_sec = time;
165 i = settimeofday(×truct, 0);
166 if (i == -1) {
167 perror("couldn't set time of day");
168 exit(EXIT_FAILURE);
169 } else {
170 (void) printf("%s", ctime(×truct.tv_sec));
171 #if defined(i386)
172 (void) system("/usr/sbin/rtc -c > /dev/null 2>&1");
173 #endif
174 }
175 return (EXIT_SUCCESS);
176 }
177
178 /*ARGSUSED*/
179 static void
timeout(int sig)180 timeout(int sig)
181 {
182 (void) fputs("couldn't contact time server\n", stderr);
183 exit(EXIT_FAILURE);
184 /* NOTREACHED */
185 }
186