xref: /netbsd-src/bin/date/netdate.c (revision aaf4ece63a859a04e37cf3a7229b5fab0157cc06)
1 /* $NetBSD: netdate.c,v 1.24 2003/08/07 09:05:09 agc Exp $ */
2 
3 /*-
4  * Copyright (c) 1990, 1993
5  *	The Regents of the University of California.  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. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)netdate.c	8.2 (Berkeley) 4/28/95";
36 #else
37 __RCSID("$NetBSD: netdate.c,v 1.24 2003/08/07 09:05:09 agc Exp $");
38 #endif
39 #endif /* not lint */
40 
41 #include <sys/param.h>
42 #include <sys/time.h>
43 #include <sys/socket.h>
44 
45 #include <netinet/in.h>
46 #include <netdb.h>
47 #define TSPTYPES
48 #include <protocols/timed.h>
49 
50 #include <err.h>
51 #include <errno.h>
52 #include <poll.h>
53 #include <stdio.h>
54 #include <string.h>
55 #include <unistd.h>
56 
57 #include "extern.h"
58 
59 #define	WAITACK		2	/* seconds */
60 #define	WAITDATEACK	5	/* seconds */
61 
62 extern int retval;
63 
64 /*
65  * Set the date in the machines controlled by timedaemons by communicating the
66  * new date to the local timedaemon.  If the timedaemon is in the master state,
67  * it performs the correction on all slaves.  If it is in the slave state, it
68  * notifies the master that a correction is needed.
69  * Returns 0 on success.  Returns > 0 on failure, setting retval to 2;
70  */
71 int
72 netsettime(time_t tval)
73 {
74 	struct sockaddr_in dest, from, nsin;
75 	struct tsp msg;
76 	char hostname[MAXHOSTNAMELEN];
77 	struct servent *sp;
78 	struct pollfd ready[1];
79 	long waittime;
80 	int error, found, s, timed_ack;
81 	socklen_t length;
82 #ifdef IP_PORTRANGE
83 	int on;
84 #endif
85 
86 	if ((sp = getservbyname("timed", "udp")) == NULL) {
87 		warnx("udp/timed: unknown service");
88 		return (retval = 2);
89 	}
90 
91 	(void)memset(&dest, 0, sizeof(dest));
92 #ifdef BSD4_4
93 	dest.sin_len = sizeof(struct sockaddr_in);
94 #endif
95 	dest.sin_family = AF_INET;
96 	dest.sin_port = sp->s_port;
97 	dest.sin_addr.s_addr = htonl(INADDR_ANY);
98 	s = socket(AF_INET, SOCK_DGRAM, 0);
99 	if (s < 0) {
100 		if (errno != EPROTONOSUPPORT)
101 			warn("timed");
102 		return (retval = 2);
103 	}
104 
105 #ifdef IP_PORTRANGE
106 	on = IP_PORTRANGE_LOW;
107 	if (setsockopt(s, IPPROTO_IP, IP_PORTRANGE, &on, sizeof(on)) < 0) {
108 		warn("setsockopt");
109 		goto bad;
110 	}
111 #endif
112 
113 	(void)memset(&nsin, 0, sizeof(nsin));
114 #ifdef BSD4_4
115 	nsin.sin_len = sizeof(struct sockaddr_in);
116 #endif
117 	nsin.sin_family = AF_INET;
118 	if (bind(s, (struct sockaddr *)&nsin, sizeof(nsin)) < 0) {
119 		warn("bind");
120 		goto bad;
121 	}
122 
123 	msg.tsp_type = TSP_SETDATE;
124 	msg.tsp_vers = TSPVERSION;
125 	if (gethostname(hostname, sizeof(hostname))) {
126 		warn("gethostname");
127 		goto bad;
128 	}
129 	hostname[sizeof(hostname) - 1] = '\0';
130 	(void)strlcpy(msg.tsp_name, hostname, sizeof(msg.tsp_name));
131 	msg.tsp_seq = htons((u_short)0);
132 	msg.tsp_time.tv_sec = htonl((u_long)tval);
133 	msg.tsp_time.tv_usec = htonl((u_long)0);
134 	length = sizeof(struct sockaddr_in);
135 	if (connect(s, (struct sockaddr *)&dest, length) < 0) {
136 		warn("connect");
137 		goto bad;
138 	}
139 	if (send(s, (char *)&msg, sizeof(struct tsp), 0) < 0) {
140 		if (errno != ECONNREFUSED)
141 			warn("send");
142 		goto bad;
143 	}
144 
145 	timed_ack = -1;
146 	waittime = WAITACK;
147 	ready[0].fd = s;
148 	ready[0].events = POLLIN;
149 loop:
150 	found = poll(ready, 1, waittime * 1000);
151 
152 	length = sizeof(error);
153 	if (!getsockopt(s,
154 	    SOL_SOCKET, SO_ERROR, (char *)&error, &length) && error) {
155 		if (error != ECONNREFUSED)
156 			warn("send (delayed error)");
157 		goto bad;
158 	}
159 
160 	if (found > 0 && ready[0].revents & POLLIN) {
161 		length = sizeof(struct sockaddr_in);
162 		if (recvfrom(s, &msg, sizeof(struct tsp), 0,
163 		    (struct sockaddr *)&from, &length) < 0) {
164 			if (errno != ECONNREFUSED)
165 				warn("recvfrom");
166 			goto bad;
167 		}
168 		msg.tsp_seq = ntohs(msg.tsp_seq);
169 		msg.tsp_time.tv_sec = ntohl(msg.tsp_time.tv_sec);
170 		msg.tsp_time.tv_usec = ntohl(msg.tsp_time.tv_usec);
171 		switch (msg.tsp_type) {
172 		case TSP_ACK:
173 			timed_ack = TSP_ACK;
174 			waittime = WAITDATEACK;
175 			goto loop;
176 		case TSP_DATEACK:
177 			(void)close(s);
178 			return (0);
179 		default:
180 			warnx("wrong ack received from timed: %s",
181 			    tsptype[msg.tsp_type]);
182 			timed_ack = -1;
183 			break;
184 		}
185 	}
186 	if (timed_ack == -1)
187 		warnx("can't reach time daemon, time set locally");
188 
189 bad:
190 	(void)close(s);
191 	return (retval = 2);
192 }
193