1 /* $NetBSD: talkd.c,v 1.17 2003/08/07 09:46:51 agc 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\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 #else 42 __RCSID("$NetBSD: talkd.c,v 1.17 2003/08/07 09:46:51 agc 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 70 CTL_MSG request; 71 CTL_RESPONSE response; 72 73 int sockt = STDIN_FILENO; 74 int debug = 0; 75 int logging = 0; 76 long lastmsgtime; 77 78 char hostname[MAXHOSTNAMELEN + 1]; 79 80 #define TIMEOUT 30 81 #define MAXIDLE 120 82 83 static void timeout __P((int)); 84 int main __P((int, char *[])); 85 86 int 87 main(argc, argv) 88 int argc; 89 char *argv[]; 90 { 91 CTL_MSG *mp = &request; 92 int cc, ch; 93 struct sockaddr ctl_addr; 94 95 openlog("talkd", LOG_PID, LOG_DAEMON); 96 while ((ch = getopt(argc, argv, "dl")) != -1) 97 switch (ch) { 98 case 'd': 99 debug = 1; 100 break; 101 case 'l': 102 logging = 1; 103 break; 104 default: 105 syslog(LOG_ERR, "Usage: %s [-dl]", getprogname()); 106 exit(1); 107 } 108 109 if (gethostname(hostname, sizeof hostname) < 0) { 110 syslog(LOG_ERR, "gethostname: %m"); 111 _exit(1); 112 } 113 hostname[MAXHOSTNAMELEN] = '\0'; /* ensure null termination */ 114 if (chdir(_PATH_DEV) < 0) { 115 syslog(LOG_ERR, "chdir: %s: %m", _PATH_DEV); 116 _exit(1); 117 } 118 signal(SIGALRM, timeout); 119 alarm(TIMEOUT); 120 for (;;) { 121 memset(&response, 0, sizeof(response)); 122 cc = recv(0, (char *)mp, sizeof (*mp), 0); 123 if (cc != sizeof (*mp)) { 124 if (cc < 0 && errno != EINTR) 125 syslog(LOG_WARNING, "recv: %m"); 126 continue; 127 } 128 129 mp->l_name[sizeof(mp->l_name) - 1] = '\0'; 130 mp->r_name[sizeof(mp->r_name) - 1] = '\0'; 131 mp->r_tty[sizeof(mp->r_tty) - 1] = '\0'; 132 133 lastmsgtime = time(0); 134 process_request(mp, &response); 135 136 (void)memcpy(&ctl_addr, &mp->ctl_addr, sizeof(ctl_addr)); 137 ctl_addr.sa_family = mp->ctl_addr.sa_family; 138 ctl_addr.sa_len = sizeof(ctl_addr); 139 if (ctl_addr.sa_family != AF_INET) 140 continue; 141 142 /* can block here, is this what I want? */ 143 cc = sendto(sockt, (char *)&response, sizeof (response), 0, 144 &ctl_addr, sizeof (ctl_addr)); 145 if (cc != sizeof (response)) 146 syslog(LOG_WARNING, "sendto: %m"); 147 } 148 } 149 150 void 151 timeout(n) 152 int n; 153 { 154 int save_errno = errno; 155 156 if (time(0) - lastmsgtime >= MAXIDLE) 157 _exit(0); 158 alarm(TIMEOUT); 159 errno = save_errno; 160 } 161