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 #if 0
34 static char sccsid[] = "@(#)announce.c 8.3 (Berkeley) 4/28/95";
35 #endif
36 #endif /* not lint */
37
38 #include <sys/types.h>
39 #include <sys/uio.h>
40 #include <sys/stat.h>
41 #include <sys/time.h>
42 #include <sys/wait.h>
43 #include <sys/socket.h>
44
45 #include <protocols/talkd.h>
46
47 #include <errno.h>
48 #include <paths.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <syslog.h>
53 #include <unistd.h>
54 #include <vis.h>
55
56 #include "ttymsg.h"
57 #include "extern.h"
58
59 /*
60 * Announce an invitation to talk.
61 */
62
63 /*
64 * See if the user is accepting messages. If so, announce that
65 * a talk is requested.
66 */
67 int
announce(CTL_MSG * request,const char * remote_machine)68 announce(CTL_MSG *request, const char *remote_machine)
69 {
70 char full_tty[32];
71 struct stat stbuf;
72
73 (void)snprintf(full_tty, sizeof(full_tty),
74 "%s%s", _PATH_DEV, request->r_tty);
75 if (stat(full_tty, &stbuf) < 0 || (stbuf.st_mode&020) == 0)
76 return (PERMISSION_DENIED);
77 return (print_mesg(request->r_tty, request, remote_machine));
78 }
79
80 #define max(a,b) ( (a) > (b) ? (a) : (b) )
81 #define N_LINES 5
82 #define N_CHARS 256
83
84 /*
85 * Build a block of characters containing the message.
86 * It is sent blank filled and in a single block to
87 * try to keep the message in one piece if the recipient
88 * in vi at the time
89 */
90 int
print_mesg(const char * tty,CTL_MSG * request,const char * remote_machine)91 print_mesg(const char *tty, CTL_MSG *request,
92 const char *remote_machine)
93 {
94 struct timeval now;
95 time_t clock_sec;
96 struct tm *localclock;
97 struct iovec iovec;
98 char line_buf[N_LINES][N_CHARS];
99 int sizes[N_LINES];
100 char big_buf[N_LINES*N_CHARS];
101 char *bptr, *lptr, *vis_user;
102 int i, j, max_size;
103
104 i = 0;
105 max_size = 0;
106 gettimeofday(&now, NULL);
107 clock_sec = now.tv_sec;
108 localclock = localtime(&clock_sec);
109 (void)snprintf(line_buf[i], N_CHARS, " ");
110 sizes[i] = strlen(line_buf[i]);
111 max_size = max(max_size, sizes[i]);
112 i++;
113 (void)snprintf(line_buf[i], N_CHARS,
114 "Message from Talk_Daemon@%s at %d:%02d on %d/%.2d/%.2d ...",
115 hostname, localclock->tm_hour , localclock->tm_min,
116 localclock->tm_year + 1900, localclock->tm_mon + 1,
117 localclock->tm_mday);
118 sizes[i] = strlen(line_buf[i]);
119 max_size = max(max_size, sizes[i]);
120 i++;
121
122 vis_user = malloc(strlen(request->l_name) * 4 + 1);
123 strvis(vis_user, request->l_name, VIS_CSTYLE);
124 (void)snprintf(line_buf[i], N_CHARS,
125 "talk: connection requested by %s@%s", 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, "talk: respond with: talk %s@%s",
130 vis_user, remote_machine);
131 sizes[i] = strlen(line_buf[i]);
132 max_size = max(max_size, sizes[i]);
133 i++;
134 (void)snprintf(line_buf[i], N_CHARS, " ");
135 sizes[i] = strlen(line_buf[i]);
136 max_size = max(max_size, sizes[i]);
137 i++;
138 bptr = big_buf;
139 *bptr++ = '\007'; /* send something to wake them up */
140 *bptr++ = '\r'; /* add a \r in case of raw mode */
141 *bptr++ = '\n';
142 for (i = 0; i < N_LINES; i++) {
143 /* copy the line into the big buffer */
144 lptr = line_buf[i];
145 while (*lptr != '\0')
146 *(bptr++) = *(lptr++);
147 /* pad out the rest of the lines with blanks */
148 for (j = sizes[i]; j < max_size + 2; j++)
149 *(bptr++) = ' ';
150 *(bptr++) = '\r'; /* add a \r in case of raw mode */
151 *(bptr++) = '\n';
152 }
153 *bptr = '\0';
154 iovec.iov_base = big_buf;
155 iovec.iov_len = bptr - big_buf;
156 /*
157 * we choose a timeout of RING_WAIT-5 seconds so that we don't
158 * stack up processes trying to write messages to a tty
159 * that is permanently blocked.
160 */
161 if (ttymsg(&iovec, 1, tty, RING_WAIT - 5) != NULL)
162 return (FAILED);
163
164 return (SUCCESS);
165 }
166