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 /*static char sccsid[] = "from: @(#)announce.c 5.9 (Berkeley) 2/26/91";*/ 36 static char rcsid[] = "$Id: announce.c,v 1.3 1994/12/21 20:03:48 glass Exp $"; 37 #endif /* not lint */ 38 39 #include <sys/types.h> 40 #include <sys/stat.h> 41 #include <sys/time.h> 42 #include <sys/wait.h> 43 #include <sys/socket.h> 44 #include <protocols/talkd.h> 45 #include <sgtty.h> 46 #include <errno.h> 47 #include <syslog.h> 48 #include <unistd.h> 49 #include <stdio.h> 50 #include <string.h> 51 #include <vis.h> 52 #include <paths.h> 53 54 extern char hostname[]; 55 56 /* 57 * Announce an invitation to talk. 58 * 59 * Because the tty driver insists on attaching a terminal-less 60 * process to any terminal that it writes on, we must fork a child 61 * to protect ourselves 62 */ 63 announce(request, remote_machine) 64 CTL_MSG *request; 65 char *remote_machine; 66 { 67 int pid, val, status; 68 69 if (pid = fork()) { 70 /* we are the parent, so wait for the child */ 71 if (pid == -1) /* the fork failed */ 72 return (FAILED); 73 do { 74 val = wait(&status); 75 if (val == -1) { 76 if (errno == EINTR) 77 continue; 78 /* shouldn't happen */ 79 syslog(LOG_WARNING, "announce: wait: %m"); 80 return (FAILED); 81 } 82 } while (val != pid); 83 if (status&0377 > 0) /* we were killed by some signal */ 84 return (FAILED); 85 /* Get the second byte, this is the exit/return code */ 86 return ((status >> 8) & 0377); 87 } 88 /* we are the child, go and do it */ 89 _exit(announce_proc(request, remote_machine)); 90 } 91 92 /* 93 * See if the user is accepting messages. If so, announce that 94 * a talk is requested. 95 */ 96 announce_proc(request, remote_machine) 97 CTL_MSG *request; 98 char *remote_machine; 99 { 100 int pid, status; 101 char full_tty[32]; 102 FILE *tf; 103 struct stat stbuf; 104 105 (void)sprintf(full_tty, "%s/%s", _PATH_DEV, request->r_tty); 106 if (access(full_tty, 0) != 0) 107 return (FAILED); 108 if ((tf = fopen(full_tty, "w")) == NULL) 109 return (PERMISSION_DENIED); 110 /* 111 * On first tty open, the server will have 112 * it's pgrp set, so disconnect us from the 113 * tty before we catch a signal. 114 */ 115 ioctl(fileno(tf), TIOCNOTTY, (struct sgttyb *) 0); 116 if (fstat(fileno(tf), &stbuf) < 0) 117 return (PERMISSION_DENIED); 118 if ((stbuf.st_mode&020) == 0) 119 return (PERMISSION_DENIED); 120 print_mesg(tf, request, remote_machine); 121 fclose(tf); 122 return (SUCCESS); 123 } 124 125 #define max(a,b) ( (a) > (b) ? (a) : (b) ) 126 #define N_LINES 5 127 #define N_CHARS 120 128 129 /* 130 * Build a block of characters containing the message. 131 * It is sent blank filled and in a single block to 132 * try to keep the message in one piece if the recipient 133 * in in vi at the time 134 */ 135 print_mesg(tf, request, remote_machine) 136 FILE *tf; 137 CTL_MSG *request; 138 char *remote_machine; 139 { 140 struct timeval clock; 141 struct timezone zone; 142 struct tm *localtime(); 143 struct tm *localclock; 144 char line_buf[N_LINES][N_CHARS]; 145 int sizes[N_LINES]; 146 char big_buf[N_LINES*N_CHARS]; 147 char *bptr, *lptr, *vis_user; 148 int i, j, max_size; 149 150 i = 0; 151 max_size = 0; 152 gettimeofday(&clock, &zone); 153 localclock = localtime( &clock.tv_sec ); 154 (void)sprintf(line_buf[i], " "); 155 sizes[i] = strlen(line_buf[i]); 156 max_size = max(max_size, sizes[i]); 157 i++; 158 (void)sprintf(line_buf[i], "Message from Talk_Daemon@%s at %d:%02d ...", 159 hostname, localclock->tm_hour , localclock->tm_min ); 160 sizes[i] = strlen(line_buf[i]); 161 max_size = max(max_size, sizes[i]); 162 i++; 163 vis_user = (char *) malloc(strlen(request->l_name) * 4 + 1); 164 strvis(vis_user, request->l_name, VIS_CSTYLE); 165 (void)sprintf(line_buf[i], "talk: connection requested by %s@%s.", 166 vis_user, remote_machine); 167 sizes[i] = strlen(line_buf[i]); 168 max_size = max(max_size, sizes[i]); 169 i++; 170 (void)sprintf(line_buf[i], "talk: respond with: talk %s@%s", 171 vis_user, remote_machine); 172 sizes[i] = strlen(line_buf[i]); 173 max_size = max(max_size, sizes[i]); 174 i++; 175 (void)sprintf(line_buf[i], " "); 176 sizes[i] = strlen(line_buf[i]); 177 max_size = max(max_size, sizes[i]); 178 i++; 179 bptr = big_buf; 180 *bptr++ = ''; /* send something to wake them up */ 181 *bptr++ = '\r'; /* add a \r in case of raw mode */ 182 *bptr++ = '\n'; 183 for (i = 0; i < N_LINES; i++) { 184 /* copy the line into the big buffer */ 185 lptr = line_buf[i]; 186 while (*lptr != '\0') 187 *(bptr++) = *(lptr++); 188 /* pad out the rest of the lines with blanks */ 189 for (j = sizes[i]; j < max_size + 2; j++) 190 *(bptr++) = ' '; 191 *(bptr++) = '\r'; /* add a \r in case of raw mode */ 192 *(bptr++) = '\n'; 193 } 194 *bptr = '\0'; 195 fprintf(tf, big_buf); 196 fflush(tf); 197 ioctl(fileno(tf), TIOCNOTTY, (struct sgttyb *) 0); 198 } 199