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 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 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