1/*	$NetBSD: talkd.c,v 1.20 2008/07/20 01:09:07 lukem Exp $	*/
2
3/*
4 * Copyright (c) 1983, 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__COPYRIGHT("@(#) Copyright (c) 1983, 1993\
35 The Regents of the University of California.  All rights reserved.");
36#endif /* not lint */
37
38#ifndef lint
39#if 0
40static char sccsid[] = "@(#)talkd.c	8.1 (Berkeley) 6/4/93";
41#else
42__RCSID("$NetBSD: talkd.c,v 1.20 2008/07/20 01:09:07 lukem Exp $");
43#endif
44#endif /* not lint */
45
46/*
47 * The top level of the daemon, the format is heavily borrowed
48 * from rwhod.c. Basically: find out who and where you are;
49 * disconnect all descriptors and ttys, and then endless
50 * loop on waiting for and processing requests
51 */
52#include <sys/types.h>
53#include <sys/socket.h>
54#include <sys/param.h>
55
56#include <protocols/talkd.h>
57
58#include <errno.h>
59#include <paths.h>
60#include <signal.h>
61#include <stdio.h>
62#include <stdlib.h>
63#include <string.h>
64#include <syslog.h>
65#include <time.h>
66#include <unistd.h>
67
68#include "extern.h"
69
70CTL_MSG		request;
71CTL_RESPONSE	response;
72
73int	sockt = STDIN_FILENO;
74int	debug = 0;
75int	logging = 0;
76time_t	lastmsgtime;
77
78char	hostname[MAXHOSTNAMELEN + 1];
79
80#define TIMEOUT 30
81#define MAXIDLE 120
82
83static void timeout(int);
84int	main(int, char *[]);
85
86int
87main(int argc, char *argv[])
88{
89	CTL_MSG *mp = &request;
90	int cc, ch;
91	struct sockaddr ctl_addr;
92
93	openlog("talkd", LOG_PID, LOG_DAEMON);
94	while ((ch = getopt(argc, argv, "dl")) != -1)
95		switch (ch) {
96		case 'd':
97			debug = 1;
98			break;
99		case 'l':
100			logging = 1;
101			break;
102		default:
103			syslog(LOG_ERR, "Usage: %s [-dl]", getprogname());
104			exit(1);
105		}
106
107	if (gethostname(hostname, sizeof hostname) < 0) {
108		syslog(LOG_ERR, "gethostname: %m");
109		_exit(1);
110	}
111	hostname[MAXHOSTNAMELEN] = '\0';  /* ensure null termination */
112	if (chdir(_PATH_DEV) < 0) {
113		syslog(LOG_ERR, "chdir: %s: %m", _PATH_DEV);
114		_exit(1);
115	}
116	signal(SIGALRM, timeout);
117	alarm(TIMEOUT);
118	for (;;) {
119		memset(&response, 0, sizeof(response));
120		cc = recv(0, (char *)mp, sizeof (*mp), 0);
121		if (cc != sizeof (*mp)) {
122			if (cc < 0 && errno != EINTR)
123				syslog(LOG_WARNING, "recv: %m");
124			continue;
125		}
126
127		mp->l_name[sizeof(mp->l_name) - 1] = '\0';
128		mp->r_name[sizeof(mp->r_name) - 1] = '\0';
129		mp->r_tty[sizeof(mp->r_tty) - 1] = '\0';
130
131		lastmsgtime = time(0);
132		process_request(mp, &response);
133
134		tsa2sa(&ctl_addr, &mp->ctl_addr);
135		if (ctl_addr.sa_family != AF_INET)
136			continue;
137
138		/* can block here, is this what I want? */
139		cc = sendto(sockt, (char *)&response, sizeof (response), 0,
140		    &ctl_addr, sizeof (ctl_addr));
141		if (cc != sizeof (response))
142			syslog(LOG_WARNING, "sendto: %m");
143	}
144}
145
146void
147timeout(int n)
148{
149	int save_errno = errno;
150
151	if (time(0) - lastmsgtime >= MAXIDLE)
152		_exit(0);
153	alarm(TIMEOUT);
154	errno = save_errno;
155}
156
157void
158tsa2sa(struct sockaddr *sa, const struct talkd_sockaddr *tsa)
159{
160	(void)memcpy(sa, tsa, sizeof(*tsa));
161	sa->sa_len = sizeof(*tsa);
162	sa->sa_family = tsa->sa_family;
163}
164