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