1/*	$NetBSD: announce.c,v 1.24 2009/03/16 01:04:32 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
35static char sccsid[] = "@(#)announce.c	8.3 (Berkeley) 4/28/95";
36#else
37__RCSID("$NetBSD: announce.c,v 1.24 2009/03/16 01:04:32 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
60extern 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 */
70int
71announce(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 */
93int
94print_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