1/* $NetBSD: netdate.c,v 1.30 2011/01/29 02:16:52 christos 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
35static char sccsid[] = "@(#)netdate.c	8.2 (Berkeley) 4/28/95";
36#else
37__RCSID("$NetBSD: netdate.c,v 1.30 2011/01/29 02:16:52 christos 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		2000	/* milliseconds */
60#define	WAITDATEACK	5000	/* milliseconds */
61
62static const char *
63tsp_type_to_string(const struct tsp *msg)
64{
65	unsigned i;
66
67	i = msg->tsp_type;
68	return i < TSPTYPENUMBER ? tsptype[i] : "unknown";
69}
70
71/*
72 * Set the date in the machines controlled by timedaemons by communicating the
73 * new date to the local timedaemon.  If the timedaemon is in the master state,
74 * it performs the correction on all slaves.  If it is in the slave state, it
75 * notifies the master that a correction is needed.
76 * Returns 0 on success.  Returns > 0 on failure.
77 */
78int
79netsettime(time_t tval)
80{
81	struct sockaddr_in dest;
82	struct tsp msg;
83	char hostname[MAXHOSTNAMELEN];
84	struct servent *sp;
85	struct pollfd ready;
86	int found, s, timed_ack, waittime;
87
88	if ((sp = getservbyname("timed", "udp")) == NULL) {
89		warnx("udp/timed: unknown service");
90		return 2;
91	}
92
93	(void)memset(&dest, 0, sizeof(dest));
94#ifdef BSD4_4
95	dest.sin_len = sizeof(dest);
96#endif
97	dest.sin_family = AF_INET;
98	dest.sin_port = sp->s_port;
99	dest.sin_addr.s_addr = htonl(INADDR_ANY);
100	s = socket(AF_INET, SOCK_DGRAM, 0);
101	if (s == -1) {
102		if (errno != EAFNOSUPPORT)
103			warn("timed");
104		return 2;
105	}
106
107#ifdef IP_PORTRANGE
108	{
109		static const int on = IP_PORTRANGE_LOW;
110
111		if (setsockopt(s, IPPROTO_IP, IP_PORTRANGE, &on,
112		    sizeof(on)) == -1) {
113			warn("setsockopt");
114			goto bad;
115		}
116	}
117#endif
118
119	msg.tsp_type = TSP_SETDATE;
120	msg.tsp_vers = TSPVERSION;
121	if (gethostname(hostname, sizeof(hostname)) == -1) {
122		warn("gethostname");
123		goto bad;
124	}
125	(void)strlcpy(msg.tsp_name, hostname, sizeof(msg.tsp_name));
126	msg.tsp_seq = htons((in_port_t)0);
127	msg.tsp_time.tv_sec = htonl((in_addr_t)tval); /* XXX: y2038 */
128	msg.tsp_time.tv_usec = htonl((in_addr_t)0);
129	if (connect(s, (const void *)&dest, sizeof(dest)) == -1) {
130		warn("connect");
131		goto bad;
132	}
133	if (send(s, &msg, sizeof(msg), 0) == -1) {
134		if (errno != ECONNREFUSED)
135			warn("send");
136		goto bad;
137	}
138
139	timed_ack = -1;
140	waittime = WAITACK;
141	ready.fd = s;
142	ready.events = POLLIN;
143loop:
144	found = poll(&ready, 1, waittime);
145
146	{
147		socklen_t len;
148		int error;
149
150		len = sizeof(error);
151		if (getsockopt(s, SOL_SOCKET, SO_ERROR, &error, &len) == -1) {
152			warn("getsockopt");
153			goto bad;
154		}
155		if (error) {
156			if (error != ECONNREFUSED) {
157				errno = error;
158				warn("send (delayed error)");
159			}
160			goto bad;
161		}
162	}
163
164	if (found > 0 && ready.revents & POLLIN) {
165		ssize_t ret;
166
167		if ((ret = recv(s, &msg, sizeof(msg), 0)) == -1) {
168			if (errno != ECONNREFUSED)
169				warn("recv");
170			goto bad;
171		} else if ((size_t)ret < sizeof(msg)) {
172			warnx("recv: incomplete packet");
173			goto bad;
174		}
175
176		msg.tsp_seq = ntohs(msg.tsp_seq);
177		msg.tsp_time.tv_sec = ntohl(msg.tsp_time.tv_sec);
178		msg.tsp_time.tv_usec = ntohl(msg.tsp_time.tv_usec);
179		switch (msg.tsp_type) {
180		case TSP_ACK:
181			timed_ack = TSP_ACK;
182			waittime = WAITDATEACK;
183			goto loop;
184		case TSP_DATEACK:
185			(void)close(s);
186			return 0;
187		default:
188			warnx("wrong ack received from timed: %s",
189			    tsp_type_to_string(&msg));
190			timed_ack = -1;
191			break;
192		}
193	}
194	if (timed_ack == -1)
195		warnx("can't reach time daemon, time set locally");
196
197bad:
198	(void)close(s);
199	return 2;
200}
201