xref: /freebsd/libexec/talkd/announce.c (revision b52b9d56d4e96089873a75f9e29062eec19fabba)
1 /*
2  * Copyright (c) 1983, 1993
3  *	The Regents of the University of California.  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 #if 0
36 static char sccsid[] = "@(#)announce.c	8.3 (Berkeley) 4/28/95";
37 #endif
38 static const char rcsid[] =
39   "$FreeBSD$";
40 #endif /* not lint */
41 
42 #include <sys/types.h>
43 #include <sys/uio.h>
44 #include <sys/stat.h>
45 #include <sys/time.h>
46 #include <sys/wait.h>
47 #include <sys/socket.h>
48 
49 #include <protocols/talkd.h>
50 
51 #include <errno.h>
52 #include <paths.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <string.h>
56 #include <syslog.h>
57 #include <unistd.h>
58 #include <vis.h>
59 
60 #include "ttymsg.h"
61 #include "extern.h"
62 
63 extern char hostname[];
64 
65 /*
66  * Announce an invitation to talk.
67  */
68 
69 /*
70  * See if the user is accepting messages. If so, announce that
71  * a talk is requested.
72  */
73 int
74 announce(CTL_MSG *request, const char *remote_machine)
75 {
76 	char full_tty[32];
77 	FILE *tf;
78 	struct stat stbuf;
79 
80 	(void)snprintf(full_tty, sizeof(full_tty),
81 	    "%s%s", _PATH_DEV, request->r_tty);
82 	if (stat(full_tty, &stbuf) < 0 || (stbuf.st_mode&020) == 0)
83 		return (PERMISSION_DENIED);
84 	return (print_mesg(request->r_tty, tf, request, remote_machine));
85 }
86 
87 #define max(a,b) ( (a) > (b) ? (a) : (b) )
88 #define N_LINES 5
89 #define N_CHARS 256
90 
91 /*
92  * Build a block of characters containing the message.
93  * It is sent blank filled and in a single block to
94  * try to keep the message in one piece if the recipient
95  * in in vi at the time
96  */
97 int
98 print_mesg(const char *tty, FILE *tf, CTL_MSG *request,
99     const char *remote_machine)
100 {
101 	struct timeval clock;
102 	time_t clock_sec;
103 	struct timezone zone;
104 	struct tm *localtime();
105 	struct tm *localclock;
106 	struct iovec iovec;
107 	char line_buf[N_LINES][N_CHARS];
108 	int sizes[N_LINES];
109 	char big_buf[N_LINES*N_CHARS];
110 	char *bptr, *lptr, *vis_user;
111 	int i, j, max_size;
112 
113 	i = 0;
114 	max_size = 0;
115 	gettimeofday(&clock, &zone);
116 	clock_sec = clock.tv_sec;
117 	localclock = localtime(&clock_sec);
118 	(void)snprintf(line_buf[i], N_CHARS, " ");
119 	sizes[i] = strlen(line_buf[i]);
120 	max_size = max(max_size, sizes[i]);
121 	i++;
122 	(void)snprintf(line_buf[i], N_CHARS,
123 		"Message from Talk_Daemon@%s at %d:%02d on %d/%.2d/%.2d ...",
124 		hostname, localclock->tm_hour , localclock->tm_min,
125 		localclock->tm_year + 1900, localclock->tm_mon + 1,
126 		localclock->tm_mday);
127 	sizes[i] = strlen(line_buf[i]);
128 	max_size = max(max_size, sizes[i]);
129 	i++;
130 
131 	vis_user = malloc(strlen(request->l_name) * 4 + 1);
132 	strvis(vis_user, request->l_name, VIS_CSTYLE);
133 	(void)snprintf(line_buf[i], N_CHARS,
134 	    "talk: connection requested by %s@%s", vis_user, remote_machine);
135 	sizes[i] = strlen(line_buf[i]);
136 	max_size = max(max_size, sizes[i]);
137 	i++;
138 	(void)snprintf(line_buf[i], N_CHARS, "talk: respond with:  talk %s@%s",
139 	    vis_user, remote_machine);
140 	sizes[i] = strlen(line_buf[i]);
141 	max_size = max(max_size, sizes[i]);
142 	i++;
143 	(void)snprintf(line_buf[i], N_CHARS, " ");
144 	sizes[i] = strlen(line_buf[i]);
145 	max_size = max(max_size, sizes[i]);
146 	i++;
147 	bptr = big_buf;
148 	*bptr++ = '\007'; /* send something to wake them up */
149 	*bptr++ = '\r';	/* add a \r in case of raw mode */
150 	*bptr++ = '\n';
151 	for (i = 0; i < N_LINES; i++) {
152 		/* copy the line into the big buffer */
153 		lptr = line_buf[i];
154 		while (*lptr != '\0')
155 			*(bptr++) = *(lptr++);
156 		/* pad out the rest of the lines with blanks */
157 		for (j = sizes[i]; j < max_size + 2; j++)
158 			*(bptr++) = ' ';
159 		*(bptr++) = '\r';	/* add a \r in case of raw mode */
160 		*(bptr++) = '\n';
161 	}
162 	*bptr = '\0';
163 	iovec.iov_base = big_buf;
164 	iovec.iov_len = bptr - big_buf;
165 	/*
166 	 * we choose a timeout of RING_WAIT-5 seconds so that we don't
167 	 * stack up processes trying to write messages to a tty
168 	 * that is permanently blocked.
169 	 */
170 	if (ttymsg(&iovec, 1, tty, RING_WAIT - 5) != NULL)
171 		return (FAILED);
172 
173 	return (SUCCESS);
174 }
175