1/*
2 * SPDX-License-Identifier: BSD-3-Clause
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#ifndef lint
33static const char copyright[] =
34"@(#) Copyright (c) 1983, 1993\n\
35	The Regents of the University of California.  All rights reserved.\n";
36#endif /* not lint */
37
38#ifndef lint
39#if 0
40static char sccsid[] = "@(#)talkd.c	8.1 (Berkeley) 6/4/93";
41#endif
42static const char rcsid[] =
43  "$FreeBSD$";
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#include <netinet/in.h>
56#include <protocols/talkd.h>
57#include <err.h>
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
70static CTL_MSG		request;
71static CTL_RESPONSE	response;
72
73int			debug = 0;
74static long		lastmsgtime;
75
76char			hostname[MAXHOSTNAMELEN];
77
78#define TIMEOUT 30
79#define MAXIDLE 120
80
81int
82main(int argc, char *argv[])
83{
84	register CTL_MSG *mp = &request;
85	int cc;
86	struct sockaddr ctl_addr;
87
88#ifdef NOTDEF
89	/*
90	 * removed so ntalkd can run in tty sandbox
91	 */
92	if (getuid())
93		errx(1, "getuid: not super-user");
94#endif
95	openlog("talkd", LOG_PID, LOG_DAEMON);
96	if (gethostname(hostname, sizeof(hostname) - 1) < 0) {
97		syslog(LOG_ERR, "gethostname: %m");
98		_exit(1);
99	}
100	hostname[sizeof(hostname) - 1] = '\0';
101	if (chdir(_PATH_DEV) < 0) {
102		syslog(LOG_ERR, "chdir: %s: %m", _PATH_DEV);
103		_exit(1);
104	}
105	if (argc > 1 && strcmp(argv[1], "-d") == 0)
106		debug = 1;
107	signal(SIGALRM, timeout);
108	alarm(TIMEOUT);
109	for (;;) {
110		cc = recv(0, (char *)mp, sizeof(*mp), 0);
111		if (cc != sizeof (*mp)) {
112			if (cc < 0 && errno != EINTR)
113				syslog(LOG_WARNING, "recv: %m");
114			continue;
115		}
116		lastmsgtime = time(0);
117		(void)memcpy(&ctl_addr.sa_data, &mp->ctl_addr.sa_data,
118		    sizeof(ctl_addr.sa_data));
119		ctl_addr.sa_family = ntohs(mp->ctl_addr.sa_family);
120		ctl_addr.sa_len = sizeof(ctl_addr);
121		process_request(mp, &response);
122		/* can block here, is this what I want? */
123		cc = sendto(STDIN_FILENO, (char *)&response,
124		    sizeof(response), 0, &ctl_addr, sizeof(ctl_addr));
125		if (cc != sizeof (response))
126			syslog(LOG_WARNING, "sendto: %m");
127	}
128}
129
130void
131timeout(int sig __unused)
132{
133	int save_errno = errno;
134
135	if (time(0) - lastmsgtime >= MAXIDLE)
136		_exit(0);
137	alarm(TIMEOUT);
138	errno = save_errno;
139}
140