1 /* $OpenBSD: announce.c,v 1.26 2024/04/28 16:42:53 florian Exp $ */
2
3 /*
4 * Copyright (c) 1983 Regents of the University of California.
5 * 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/stat.h>
33 #include <protocols/talkd.h>
34
35 #include <limits.h>
36 #include <paths.h>
37 #include <stdio.h>
38 #include <string.h>
39 #include <unistd.h>
40 #include <vis.h>
41
42 #include "talkd.h"
43
44 static void print_mesg(FILE *,CTL_MSG *,char *);
45
46 /*
47 * Announce an invitation to talk. If the user is
48 * accepting messages, announce that a talk is requested.
49 */
50 int
announce(CTL_MSG * request,char * remote_machine)51 announce(CTL_MSG *request, char *remote_machine)
52 {
53 char full_tty[PATH_MAX];
54 FILE *tf;
55 struct stat stbuf;
56
57 (void)snprintf(full_tty, sizeof(full_tty), "%s/%s", _PATH_DEV,
58 request->r_tty);
59 if (access(full_tty, 0) != 0)
60 return (FAILED);
61 if ((tf = fopen(full_tty, "w")) == NULL)
62 return (PERMISSION_DENIED);
63 if (fstat(fileno(tf), &stbuf) == -1) {
64 fclose(tf);
65 return (PERMISSION_DENIED);
66 }
67 if ((stbuf.st_mode & S_IWGRP) == 0) {
68 fclose(tf);
69 return (PERMISSION_DENIED);
70 }
71 print_mesg(tf, request, remote_machine);
72 fclose(tf);
73 return (SUCCESS);
74 }
75
76 #define max(a,b) ( (a) > (b) ? (a) : (b) )
77 #define N_LINES 5
78 #define N_CHARS 120
79
80 /*
81 * Build a block of characters containing the message.
82 * It is sent blank filled and in a single block to
83 * try to keep the message in one piece if the recipient
84 * is in vi at the time
85 */
86 static void
print_mesg(FILE * tf,CTL_MSG * request,char * remote_machine)87 print_mesg(FILE *tf, CTL_MSG *request, char *remote_machine)
88 {
89 time_t clocktime;
90 struct tm *localclock;
91 char line_buf[N_LINES][N_CHARS];
92 int sizes[N_LINES];
93 char big_buf[(N_LINES + 1) * N_CHARS];
94 char *bptr, *lptr, vis_user[sizeof(request->l_name) * 4];
95 int i, j, max_size;
96
97 i = 0;
98 max_size = 0;
99 time(&clocktime);
100 localclock = localtime(&clocktime);
101 (void)snprintf(line_buf[i], N_CHARS, " ");
102 sizes[i] = strlen(line_buf[i]);
103 max_size = max(max_size, sizes[i]);
104 i++;
105 if (localclock) {
106 (void)snprintf(line_buf[i], N_CHARS,
107 "Message from Talk_Daemon@%s at %d:%02d ...",
108 hostname, localclock->tm_hour , localclock->tm_min );
109 } else {
110 (void)snprintf(line_buf[i], N_CHARS,
111 "Message from Talk_Daemon@%s ...", hostname);
112 }
113 sizes[i] = strlen(line_buf[i]);
114 max_size = max(max_size, sizes[i]);
115 i++;
116 strvis(vis_user, request->l_name, VIS_CSTYLE);
117 (void)snprintf(line_buf[i], N_CHARS,
118 "talk: connection requested by %s@%s.",
119 vis_user, remote_machine);
120 sizes[i] = strlen(line_buf[i]);
121 max_size = max(max_size, sizes[i]);
122 i++;
123 (void)snprintf(line_buf[i], N_CHARS, "talk: respond with: talk %s@%s",
124 vis_user, remote_machine);
125 sizes[i] = strlen(line_buf[i]);
126 max_size = max(max_size, sizes[i]);
127 i++;
128 (void)snprintf(line_buf[i], N_CHARS, " ");
129 sizes[i] = strlen(line_buf[i]);
130 max_size = max(max_size, sizes[i]);
131 i++;
132 bptr = big_buf;
133 *bptr++ = '\007'; /* send something to wake them up */
134 *bptr++ = '\r'; /* add a \r in case of raw mode */
135 *bptr++ = '\n';
136 for (i = 0; i < N_LINES; i++) {
137 /* copy the line into the big buffer */
138 lptr = line_buf[i];
139 while (*lptr != '\0')
140 *(bptr++) = *(lptr++);
141 /* pad out the rest of the lines with blanks */
142 for (j = sizes[i]; j < max_size + 2; j++)
143 *(bptr++) = ' ';
144 *(bptr++) = '\r'; /* add a \r in case of raw mode */
145 *(bptr++) = '\n';
146 }
147 *bptr = '\0';
148 fprintf(tf, "%s", big_buf);
149 fflush(tf);
150 }
151