talkd.c revision 50476 
1/*
2 * Copyright (c) 1983, 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 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35static const char copyright[] =
36"@(#) Copyright (c) 1983, 1993\n\
37	The Regents of the University of California.  All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41#if 0
42static char sccsid[] = "@(#)talkd.c	8.1 (Berkeley) 6/4/93";
43#endif
44static const char rcsid[] =
45  "$FreeBSD: head/libexec/talkd/talkd.c 50476 1999-08-28 00:22:10Z peter $";
46#endif /* not lint */
47
48/*
49 * The top level of the daemon, the format is heavily borrowed
50 * from rwhod.c. Basically: find out who and where you are;
51 * disconnect all descriptors and ttys, and then endless
52 * loop on waiting for and processing requests
53 */
54#include <sys/types.h>
55#include <sys/socket.h>
56#include <sys/param.h>
57#include <protocols/talkd.h>
58#include <err.h>
59#include <errno.h>
60#include <paths.h>
61#include <signal.h>
62#include <stdio.h>
63#include <stdlib.h>
64#include <string.h>
65#include <syslog.h>
66#include <time.h>
67#include <unistd.h>
68
69CTL_MSG		request;
70CTL_RESPONSE	response;
71
72int	sockt;
73int	debug = 0;
74long	lastmsgtime;
75
76char    hostname[MAXHOSTNAMELEN];
77
78#define TIMEOUT 30
79#define MAXIDLE 120
80
81void process_request __P((CTL_MSG *, CTL_RESPONSE *));
82void timeout();
83
84int
85main(argc, argv)
86	int argc;
87	char *argv[];
88{
89	register CTL_MSG *mp = &request;
90	int cc;
91
92#ifdef NOTDEF
93	/*
94	 * removed so ntalkd can run in tty sandbox
95	 */
96	if (getuid())
97		errx(1, "getuid: not super-user");
98#endif
99	openlog("talkd", LOG_PID, LOG_DAEMON);
100	if (gethostname(hostname, sizeof(hostname) - 1) < 0) {
101		syslog(LOG_ERR, "gethostname: %m");
102		_exit(1);
103	}
104	hostname[sizeof(hostname) - 1] = '\0';
105	if (chdir(_PATH_DEV) < 0) {
106		syslog(LOG_ERR, "chdir: %s: %m", _PATH_DEV);
107		_exit(1);
108	}
109	if (argc > 1 && strcmp(argv[1], "-d") == 0)
110		debug = 1;
111	signal(SIGALRM, timeout);
112	alarm(TIMEOUT);
113	for (;;) {
114		cc = recv(0, (char *)mp, sizeof (*mp), 0);
115		if (cc != sizeof (*mp)) {
116			if (cc < 0 && errno != EINTR)
117				syslog(LOG_WARNING, "recv: %m");
118			continue;
119		}
120		lastmsgtime = time(0);
121		process_request(mp, &response);
122		/* can block here, is this what I want? */
123		mp->ctl_addr.sa_family = htons(mp->ctl_addr.sa_family);
124		cc = sendto(sockt, (char *)&response,
125		    sizeof (response), 0, (struct sockaddr *)&mp->ctl_addr,
126		    sizeof (mp->ctl_addr));
127		if (cc != sizeof (response))
128			syslog(LOG_WARNING, "sendto: %m");
129	}
130}
131
132void
133timeout()
134{
135
136	if (time(0) - lastmsgtime >= MAXIDLE)
137		_exit(0);
138	alarm(TIMEOUT);
139}
140