xref: /freebsd/libexec/talkd/announce.c (revision 4f1f4356f3012928b463f9ef1710fb908e48b1e2)
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 	struct stat stbuf;
78 
79 	(void)snprintf(full_tty, sizeof(full_tty),
80 	    "%s%s", _PATH_DEV, request->r_tty);
81 	if (stat(full_tty, &stbuf) < 0 || (stbuf.st_mode&020) == 0)
82 		return (PERMISSION_DENIED);
83 	return (print_mesg(request->r_tty, request, remote_machine));
84 }
85 
86 #define max(a,b) ( (a) > (b) ? (a) : (b) )
87 #define N_LINES 5
88 #define N_CHARS 256
89 
90 /*
91  * Build a block of characters containing the message.
92  * It is sent blank filled and in a single block to
93  * try to keep the message in one piece if the recipient
94  * in vi at the time
95  */
96 int
97 print_mesg(const char *tty, CTL_MSG *request,
98     const char *remote_machine)
99 {
100 	struct timeval now;
101 	time_t clock_sec;
102 	struct tm *localclock;
103 	struct iovec iovec;
104 	char line_buf[N_LINES][N_CHARS];
105 	int sizes[N_LINES];
106 	char big_buf[N_LINES*N_CHARS];
107 	char *bptr, *lptr, *vis_user;
108 	int i, j, max_size;
109 
110 	i = 0;
111 	max_size = 0;
112 	gettimeofday(&now, NULL);
113 	clock_sec = now.tv_sec;
114 	localclock = localtime(&clock_sec);
115 	(void)snprintf(line_buf[i], N_CHARS, " ");
116 	sizes[i] = strlen(line_buf[i]);
117 	max_size = max(max_size, sizes[i]);
118 	i++;
119 	(void)snprintf(line_buf[i], N_CHARS,
120 		"Message from Talk_Daemon@%s at %d:%02d on %d/%.2d/%.2d ...",
121 		hostname, localclock->tm_hour , localclock->tm_min,
122 		localclock->tm_year + 1900, localclock->tm_mon + 1,
123 		localclock->tm_mday);
124 	sizes[i] = strlen(line_buf[i]);
125 	max_size = max(max_size, sizes[i]);
126 	i++;
127 
128 	vis_user = malloc(strlen(request->l_name) * 4 + 1);
129 	strvis(vis_user, request->l_name, VIS_CSTYLE);
130 	(void)snprintf(line_buf[i], N_CHARS,
131 	    "talk: connection requested by %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, "talk: respond with:  talk %s@%s",
136 	    vis_user, remote_machine);
137 	sizes[i] = strlen(line_buf[i]);
138 	max_size = max(max_size, sizes[i]);
139 	i++;
140 	(void)snprintf(line_buf[i], N_CHARS, " ");
141 	sizes[i] = strlen(line_buf[i]);
142 	max_size = max(max_size, sizes[i]);
143 	i++;
144 	bptr = big_buf;
145 	*bptr++ = '\007'; /* send something to wake them up */
146 	*bptr++ = '\r';	/* add a \r in case of raw mode */
147 	*bptr++ = '\n';
148 	for (i = 0; i < N_LINES; i++) {
149 		/* copy the line into the big buffer */
150 		lptr = line_buf[i];
151 		while (*lptr != '\0')
152 			*(bptr++) = *(lptr++);
153 		/* pad out the rest of the lines with blanks */
154 		for (j = sizes[i]; j < max_size + 2; j++)
155 			*(bptr++) = ' ';
156 		*(bptr++) = '\r';	/* add a \r in case of raw mode */
157 		*(bptr++) = '\n';
158 	}
159 	*bptr = '\0';
160 	iovec.iov_base = big_buf;
161 	iovec.iov_len = bptr - big_buf;
162 	/*
163 	 * we choose a timeout of RING_WAIT-5 seconds so that we don't
164 	 * stack up processes trying to write messages to a tty
165 	 * that is permanently blocked.
166 	 */
167 	if (ttymsg(&iovec, 1, tty, RING_WAIT - 5) != NULL)
168 		return (FAILED);
169 
170 	return (SUCCESS);
171 }
172