1/*-
2 * Copyright (c) 1990, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#if 0
31#ifndef lint
32static char sccsid[] = "@(#)netdate.c	8.1 (Berkeley) 5/31/93";
33#endif /* not lint */
34#endif
35
36#include <sys/cdefs.h>
37__FBSDID("$FreeBSD: src/bin/date/netdate.c,v 1.18 2004/04/06 20:06:45 markm Exp $");
38
39#include <sys/param.h>
40#include <sys/time.h>
41#include <sys/socket.h>
42
43#include <netinet/in.h>
44#include <netdb.h>
45#define TSPTYPES
46#include <protocols/timed.h>
47
48#include <err.h>
49#include <errno.h>
50#include <string.h>
51#include <unistd.h>
52
53#include "extern.h"
54
55#define	WAITACK		2	/* seconds */
56#define	WAITDATEACK	5	/* seconds */
57
58extern int retval;
59
60/*
61 * Set the date in the machines controlled by timedaemons by communicating the
62 * new date to the local timedaemon.  If the timedaemon is in the master state,
63 * it performs the correction on all slaves.  If it is in the slave state, it
64 * notifies the master that a correction is needed.
65 * Returns 0 on success.  Returns > 0 on failure, setting retval to 2;
66 */
67int
68netsettime(time_t tval)
69{
70	struct timeval tout;
71	struct servent *sp;
72	struct tsp msg;
73	struct sockaddr_in lsin, dest, from;
74	fd_set ready;
75	long waittime;
76	int s, port, timed_ack, found, lerr;
77	socklen_t length;
78	char hostname[MAXHOSTNAMELEN];
79
80	if ((sp = getservbyname("timed", "udp")) == NULL) {
81		warnx("timed/udp: unknown service");
82		return (retval = 2);
83	}
84
85	dest.sin_port = sp->s_port;
86	dest.sin_family = AF_INET;
87	dest.sin_addr.s_addr = htonl((u_long)INADDR_ANY);
88	s = socket(AF_INET, SOCK_DGRAM, 0);
89	if (s < 0) {
90		if (errno != EPROTONOSUPPORT)
91			warn("timed");
92		return (retval = 2);
93	}
94
95	memset(&lsin, 0, sizeof(lsin));
96	lsin.sin_family = AF_INET;
97	for (port = IPPORT_RESERVED - 1; port > IPPORT_RESERVED / 2; port--) {
98		lsin.sin_port = htons((u_short)port);
99		if (bind(s, (struct sockaddr *)&lsin, sizeof(lsin)) >= 0)
100			break;
101		if (errno == EADDRINUSE)
102			continue;
103		if (errno != EADDRNOTAVAIL)
104			warn("bind");
105		goto bad;
106	}
107	if (port == IPPORT_RESERVED / 2) {
108		warnx("all ports in use");
109		goto bad;
110	}
111	msg.tsp_type = TSP_SETDATE;
112	msg.tsp_vers = TSPVERSION;
113	if (gethostname(hostname, sizeof(hostname))) {
114		warn("gethostname");
115		goto bad;
116	}
117	(void)strncpy(msg.tsp_name, hostname, sizeof(msg.tsp_name) - 1);
118	msg.tsp_name[sizeof(msg.tsp_name) - 1] = '\0';
119	msg.tsp_seq = htons((u_short)0);
120	msg.tsp_time.tv_sec = htonl((u_long)tval);
121	msg.tsp_time.tv_usec = htonl((u_long)0);
122	length = sizeof(struct sockaddr_in);
123	if (connect(s, (struct sockaddr *)&dest, length) < 0) {
124		warn("connect");
125		goto bad;
126	}
127	if (send(s, (char *)&msg, sizeof(struct tsp), 0) < 0) {
128		if (errno != ECONNREFUSED)
129			warn("send");
130		goto bad;
131	}
132
133	timed_ack = -1;
134	waittime = WAITACK;
135loop:
136	tout.tv_sec = waittime;
137	tout.tv_usec = 0;
138
139	FD_ZERO(&ready);
140	FD_SET(s, &ready);
141	found = select(FD_SETSIZE, &ready, (fd_set *)0, (fd_set *)0, &tout);
142
143	length = sizeof(lerr);
144	if (!getsockopt(s,
145	    SOL_SOCKET, SO_ERROR, (char *)&lerr, &length) && lerr) {
146		if (lerr != ECONNREFUSED)
147			warnc(lerr, "send (delayed error)");
148		goto bad;
149	}
150
151	if (found > 0 && FD_ISSET(s, &ready)) {
152		length = sizeof(struct sockaddr_in);
153		if (recvfrom(s, &msg, sizeof(struct tsp), 0,
154		    (struct sockaddr *)&from, &length) < 0) {
155			if (errno != ECONNREFUSED)
156				warn("recvfrom");
157			goto bad;
158		}
159		msg.tsp_seq = ntohs(msg.tsp_seq);
160		msg.tsp_time.tv_sec = ntohl(msg.tsp_time.tv_sec);
161		msg.tsp_time.tv_usec = ntohl(msg.tsp_time.tv_usec);
162		switch (msg.tsp_type) {
163		case TSP_ACK:
164			timed_ack = TSP_ACK;
165			waittime = WAITDATEACK;
166			goto loop;
167		case TSP_DATEACK:
168			(void)close(s);
169			return (0);
170		default:
171			warnx("wrong ack received from timed: %s",
172			    tsptype[msg.tsp_type]);
173			timed_ack = -1;
174			break;
175		}
176	}
177	if (timed_ack == -1)
178		warnx("can't reach time daemon, time set locally");
179
180bad:
181	(void)close(s);
182	return (retval = 2);
183}
184