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