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
44static 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 */
50int
51announce(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 */
86static void
87print_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