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
35__attribute__((__used__))
36static const char copyright[] =
37"@(#) Copyright (c) 1983, 1993\n\
38	The Regents of the University of California.  All rights reserved.\n";
39#endif /* not lint */
40
41#ifndef lint
42#if 0
43static char sccsid[] = "@(#)talkd.c	8.1 (Berkeley) 6/4/93";
44#endif
45__attribute__((__used__))
46static const char rcsid[] =
47  "$FreeBSD: src/libexec/talkd/talkd.c,v 1.17 2004/06/14 22:44:13 bms Exp $";
48#endif /* not lint */
49
50#include <sys/cdefs.h>
51
52/*
53 * The top level of the daemon, the format is heavily borrowed
54 * from rwhod.c. Basically: find out who and where you are;
55 * disconnect all descriptors and ttys, and then endless
56 * loop on waiting for and processing requests
57 */
58#include <sys/types.h>
59#include <sys/socket.h>
60#include <sys/param.h>
61#include <netinet/in.h>
62#include <protocols/talkd.h>
63#include <err.h>
64#include <errno.h>
65#include <paths.h>
66#include <signal.h>
67#include <stdio.h>
68#include <stdlib.h>
69#include <string.h>
70#include <syslog.h>
71#include <time.h>
72#include <unistd.h>
73
74#include "extern.h"
75
76CTL_MSG		request;
77CTL_RESPONSE	response;
78
79int	debug = 0;
80long	lastmsgtime;
81
82char	hostname[MAXHOSTNAMELEN + 1];
83
84#define TIMEOUT 30
85#define MAXIDLE 120
86
87int
88main(int argc, char *argv[])
89{
90	register CTL_MSG *mp = &request;
91	int cc;
92	struct sockaddr ctl_addr;
93
94	/*
95	 * removed so ntalkd can run in tty sandbox
96	 */
97	if (getuid())
98		errx(1, "getuid: not super-user");
99
100	openlog("talkd", LOG_PID, LOG_DAEMON);
101	if (gethostname(hostname, sizeof(hostname) - 1) < 0) {
102		syslog(LOG_ERR, "gethostname: %m");
103		_exit(1);
104	}
105	hostname[sizeof(hostname) - 1] = '\0';
106	if (chdir(_PATH_DEV) < 0) {
107		syslog(LOG_ERR, "chdir: %s: %m", _PATH_DEV);
108		_exit(1);
109	}
110	if (argc > 1 && strcmp(argv[1], "-d") == 0)
111		debug = 1;
112	signal(SIGALRM, timeout);
113	alarm(TIMEOUT);
114	for (;;) {
115		cc = recv(0, (char *)mp, sizeof(*mp), 0);
116		if (cc != sizeof (*mp)) {
117			if (cc < 0 && errno != EINTR)
118				syslog(LOG_WARNING, "recv: %m");
119			continue;
120		}
121		lastmsgtime = time(0);
122		(void)memcpy(&ctl_addr, &mp->ctl_addr, sizeof(ctl_addr));
123		ctl_addr.sa_family = ntohs(mp->ctl_addr.sa_family);
124		ctl_addr.sa_len = sizeof(ctl_addr);
125		process_request(mp, &response);
126		/* can block here, is this what I want? */
127		cc = sendto(STDIN_FILENO, (char *)&response,
128		    sizeof(response), 0, &ctl_addr, sizeof(ctl_addr));
129		if (cc != sizeof (response))
130			syslog(LOG_WARNING, "sendto: %m");
131	}
132	/* NOTREACHED */
133	return 0;
134}
135
136void
137timeout(int sig __unused)
138{
139	int save_errno = errno;
140
141	if (time(0) - lastmsgtime >= MAXIDLE)
142		_exit(0);
143	alarm(TIMEOUT);
144	errno = save_errno;
145}
146