1 /*
2 * Copyright (c) 1983 Regents of the University of California.
3 * 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 char copyright[] =
36 "@(#) Copyright (c) 1983 Regents of the University of California.\n\
37 All rights reserved.\n";
38 #endif /* not lint */
39
40 #ifndef lint
41 static char sccsid[] = "@(#)talkd.c 5.8 (Berkeley) 2/26/91";
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 <protocols/talkd.h>
53 #include <signal.h>
54 #include <syslog.h>
55 #include <time.h>
56 #include <errno.h>
57 #include <unistd.h>
58 #include <stdio.h>
59 #include <stdlib.h>
60 #include <string.h>
61 #include <paths.h>
62
63 CTL_MSG request;
64 CTL_RESPONSE response;
65
66 int sockt;
67 int debug = 0;
68 void timeout();
69 long lastmsgtime;
70
71 char hostname[32];
72
73 #define TIMEOUT 30
74 #define MAXIDLE 120
75
main(argc,argv)76 main(argc, argv)
77 int argc;
78 char *argv[];
79 {
80 register CTL_MSG *mp = &request;
81 int cc;
82
83 if (getuid()) {
84 fprintf(stderr, "%s: getuid: not super-user", argv[0]);
85 exit(1);
86 }
87 openlog("talkd", LOG_PID, LOG_DAEMON);
88 if (gethostname(hostname, sizeof (hostname) - 1) < 0) {
89 syslog(LOG_ERR, "gethostname: %m");
90 _exit(1);
91 }
92 if (chdir(_PATH_DEV) < 0) {
93 syslog(LOG_ERR, "chdir: %s: %m", _PATH_DEV);
94 _exit(1);
95 }
96 if (argc > 1 && strcmp(argv[1], "-d") == 0)
97 debug = 1;
98 signal(SIGALRM, timeout);
99 alarm(TIMEOUT);
100 for (;;) {
101 extern int errno;
102
103 cc = recv(0, (char *)mp, sizeof (*mp), 0);
104 if (cc != sizeof (*mp)) {
105 if (cc < 0 && errno != EINTR)
106 syslog(LOG_WARNING, "recv: %m");
107 continue;
108 }
109 lastmsgtime = time(0);
110 process_request(mp, &response);
111 /* can block here, is this what I want? */
112 cc = sendto(sockt, (char *)&response,
113 sizeof (response), 0, (struct sockaddr *)&mp->ctl_addr,
114 sizeof (mp->ctl_addr));
115 if (cc != sizeof (response))
116 syslog(LOG_WARNING, "sendto: %m");
117 }
118 }
119
120 void
timeout()121 timeout()
122 {
123
124 if (time(0) - lastmsgtime >= MAXIDLE)
125 _exit(0);
126 alarm(TIMEOUT);
127 }
128