1 /* $NetBSD: announce.c,v 1.25 2009/03/16 01:13:38 lukem Exp $ */
2
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/cdefs.h>
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)announce.c 8.3 (Berkeley) 4/28/95";
36 #else
37 __RCSID("$NetBSD: announce.c,v 1.25 2009/03/16 01:13:38 lukem Exp $");
38 #endif
39 #endif /* not lint */
40
41 #include <sys/types.h>
42 #include <sys/uio.h>
43 #include <sys/stat.h>
44 #include <sys/time.h>
45 #include <sys/wait.h>
46 #include <sys/socket.h>
47 #include <protocols/talkd.h>
48 #include <errno.h>
49 #include <syslog.h>
50 #include <unistd.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <string.h>
54 #include <time.h>
55 #include <vis.h>
56 #include <paths.h>
57 #include <util.h>
58 #include "extern.h"
59
60 extern char hostname[];
61
62 /*
63 * Announce an invitation to talk.
64 */
65
66 /*
67 * See if the user is accepting messages. If so, announce that
68 * a talk is requested.
69 */
70 int
announce(CTL_MSG * request,const char * remote_machine)71 announce(CTL_MSG *request, const char *remote_machine)
72 {
73 char full_tty[32];
74 struct stat stbuf;
75
76 (void)snprintf(full_tty, sizeof(full_tty),
77 "%s%s", _PATH_DEV, request->r_tty);
78 if (stat(full_tty, &stbuf) < 0 || (stbuf.st_mode&S_IWGRP) == 0)
79 return (PERMISSION_DENIED);
80 return (print_mesg(request->r_tty, request, remote_machine));
81 }
82
83 #define max(a, b) ((a) > (b) ? (a) : (b))
84 #define N_LINES 5
85 #define N_CHARS 256
86
87 /*
88 * Build a block of characters containing the message.
89 * It is sent blank filled and in a single block to
90 * try to keep the message in one piece if the recipient
91 * is in vi at the time.
92 */
93 int
print_mesg(const char * tty,CTL_MSG * request,const char * remote_machine)94 print_mesg(const char *tty, CTL_MSG *request, const char *remote_machine)
95 {
96 struct timeval clocktv;
97 time_t clocktime;
98 struct tm *localclock;
99 struct iovec iovec;
100 char line_buf[N_LINES][N_CHARS];
101 int sizes[N_LINES];
102 char big_buf[(N_LINES + 1) * N_CHARS];
103 char *bptr, *lptr, vis_user[sizeof(request->l_name) * 4];
104 int i, j, max_size;
105
106 i = 0;
107 max_size = 0;
108 (void)gettimeofday(&clocktv, NULL);
109 clocktime = clocktv.tv_sec;
110 localclock = localtime(&clocktime);
111 (void)snprintf(line_buf[i], N_CHARS, " ");
112 sizes[i] = strlen(line_buf[i]);
113 max_size = max(max_size, sizes[i]);
114 i++;
115
116 (void)snprintf(line_buf[i], N_CHARS,
117 "Message from Talk_Daemon@%s at %d:%02d ...",
118 hostname, localclock->tm_hour, localclock->tm_min);
119 sizes[i] = strlen(line_buf[i]);
120 max_size = max(max_size, sizes[i]);
121 i++;
122 if (strlen(request->l_name) + 1 > sizeof(vis_user) / 4)
123 return (FAILED);
124 strvis(vis_user, request->l_name, VIS_CSTYLE);
125 (void)snprintf(line_buf[i], N_CHARS,
126 "talk: connection requested by %s@%s.", vis_user, remote_machine);
127 sizes[i] = strlen(line_buf[i]);
128 max_size = max(max_size, sizes[i]);
129 i++;
130 (void)snprintf(line_buf[i], N_CHARS,
131 "talk: respond with: talk %s@%s", vis_user, remote_machine);
132 sizes[i] = strlen(line_buf[i]);
133 max_size = max(max_size, sizes[i]);
134 i++;
135 (void)snprintf(line_buf[i], N_CHARS, " ");
136 sizes[i] = strlen(line_buf[i]);
137 max_size = max(max_size, sizes[i]);
138 i++;
139 bptr = big_buf;
140 *bptr++ = '\a'; /* send something to wake them up */
141 *bptr++ = '\r'; /* add a \r in case of raw mode */
142 *bptr++ = '\n';
143 for (i = 0; i < N_LINES; i++) {
144 /* copy the line into the big buffer */
145 lptr = line_buf[i];
146 while (*lptr != '\0' && lptr < (line_buf[i] + N_CHARS))
147 *(bptr++) = *(lptr++);
148 /* pad out the rest of the lines with blanks */
149 for (j = sizes[i]; j < max_size + 2; j++)
150 *(bptr++) = ' ';
151 *(bptr++) = '\r'; /* add a \r in case of raw mode */
152 *(bptr++) = '\n';
153 }
154 *bptr = '\0';
155 iovec.iov_base = big_buf;
156 iovec.iov_len = bptr - big_buf;
157 /*
158 * we choose a timeout of RING_WAIT-5 seconds so that we don't
159 * stack up processes trying to write messages to a tty
160 * that is permanently blocked.
161 */
162 if (ttymsg(&iovec, 1, tty, RING_WAIT - 5) != NULL)
163 return (FAILED);
164
165 return (SUCCESS);
166 }
167