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 #include <sys/types.h> 33 #include <sys/uio.h> 34 #include <sys/stat.h> 35 #include <sys/time.h> 36 #include <sys/wait.h> 37 #include <sys/socket.h> 38 39 #include <protocols/talkd.h> 40 41 #include <errno.h> 42 #include <paths.h> 43 #include <stdbool.h> 44 #include <stdio.h> 45 #include <stdlib.h> 46 #include <string.h> 47 #include <syslog.h> 48 #include <unistd.h> 49 #include <vis.h> 50 51 #include "ttymsg.h" 52 #include "extern.h" 53 54 /* 55 * Announce an invitation to talk. 56 */ 57 58 /* 59 * See if the user is accepting messages. If so, announce that 60 * a talk is requested. 61 */ 62 int 63 announce(CTL_MSG *request, const char *remote_machine) 64 { 65 char full_tty[32]; 66 struct stat stbuf; 67 68 (void)snprintf(full_tty, sizeof(full_tty), 69 "%s%s", _PATH_DEV, request->r_tty); 70 if (stat(full_tty, &stbuf) < 0 || (stbuf.st_mode&020) == 0) 71 return (PERMISSION_DENIED); 72 return (print_mesg(request->r_tty, request, remote_machine)); 73 } 74 75 #define max(a,b) ( (a) > (b) ? (a) : (b) ) 76 #define N_LINES 5 77 #define N_CHARS 256 78 79 /* 80 * Build a block of characters containing the message. 81 * It is sent blank filled and in a single block to 82 * try to keep the message in one piece if the recipient 83 * in vi at the time 84 */ 85 int 86 print_mesg(const char *tty, CTL_MSG *request, 87 const char *remote_machine) 88 { 89 struct timeval now; 90 time_t clock_sec; 91 struct tm *localclock; 92 struct iovec iovec; 93 char line_buf[N_LINES][N_CHARS]; 94 int sizes[N_LINES]; 95 char big_buf[N_LINES*N_CHARS]; 96 char *bptr, *lptr, *vis_user; 97 int i, j, max_size; 98 99 i = 0; 100 max_size = 0; 101 gettimeofday(&now, NULL); 102 clock_sec = now.tv_sec; 103 localclock = localtime(&clock_sec); 104 (void)snprintf(line_buf[i], N_CHARS, " "); 105 sizes[i] = strlen(line_buf[i]); 106 max_size = max(max_size, sizes[i]); 107 i++; 108 (void)snprintf(line_buf[i], N_CHARS, 109 "Message from Talk_Daemon@%s at %d:%02d on %d/%.2d/%.2d ...", 110 hostname, localclock->tm_hour , localclock->tm_min, 111 localclock->tm_year + 1900, localclock->tm_mon + 1, 112 localclock->tm_mday); 113 sizes[i] = strlen(line_buf[i]); 114 max_size = max(max_size, sizes[i]); 115 i++; 116 117 vis_user = malloc(strlen(request->l_name) * 4 + 1); 118 strvis(vis_user, request->l_name, VIS_CSTYLE); 119 (void)snprintf(line_buf[i], N_CHARS, 120 "talk: connection requested by %s@%s", vis_user, remote_machine); 121 sizes[i] = strlen(line_buf[i]); 122 max_size = max(max_size, sizes[i]); 123 i++; 124 (void)snprintf(line_buf[i], N_CHARS, "talk: respond with: talk %s@%s", 125 vis_user, remote_machine); 126 sizes[i] = strlen(line_buf[i]); 127 max_size = max(max_size, sizes[i]); 128 i++; 129 (void)snprintf(line_buf[i], N_CHARS, " "); 130 sizes[i] = strlen(line_buf[i]); 131 max_size = max(max_size, sizes[i]); 132 i++; 133 bptr = big_buf; 134 *bptr++ = '\007'; /* send something to wake them up */ 135 *bptr++ = '\r'; /* add a \r in case of raw mode */ 136 *bptr++ = '\n'; 137 for (i = 0; i < N_LINES; i++) { 138 /* copy the line into the big buffer */ 139 lptr = line_buf[i]; 140 while (*lptr != '\0') 141 *(bptr++) = *(lptr++); 142 /* pad out the rest of the lines with blanks */ 143 for (j = sizes[i]; j < max_size + 2; j++) 144 *(bptr++) = ' '; 145 *(bptr++) = '\r'; /* add a \r in case of raw mode */ 146 *(bptr++) = '\n'; 147 } 148 *bptr = '\0'; 149 iovec.iov_base = big_buf; 150 iovec.iov_len = bptr - big_buf; 151 /* 152 * we choose a timeout of RING_WAIT-5 seconds so that we don't 153 * stack up processes trying to write messages to a tty 154 * that is permanently blocked. 155 */ 156 if (ttymsg(&iovec, 1, tty, RING_WAIT - 5, true) != 0) 157 return (FAILED); 158 159 return (SUCCESS); 160 } 161