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#include <sys/cdefs.h>
35
36#ifndef __APPLE__
37__FBSDID("$FreeBSD: src/usr.bin/talk/look_up.c,v 1.8 2005/02/09 09:13:36 stefanf Exp $");
38
39#ifndef lint
40static const char sccsid[] = "@(#)look_up.c	8.1 (Berkeley) 6/6/93";
41#endif
42#endif /* __APPLE__ */
43
44#include <sys/types.h>
45#include <sys/socket.h>
46#include <protocols/talkd.h>
47
48#include <errno.h>
49#include <string.h>
50
51#include "talk_ctl.h"
52#include "talk.h"
53
54/*
55 * See if the local daemon has an invitation for us.
56 */
57int
58check_local()
59{
60	CTL_RESPONSE response;
61	CTL_RESPONSE *rp = &response;
62	struct sockaddr addr;
63
64	/* the rest of msg was set up in get_names */
65#ifdef MSG_EOR
66	/* copy new style sockaddr to old, swap family (short in old) */
67	msg.ctl_addr = *(struct osockaddr *)&ctl_addr;
68	msg.ctl_addr.sa_family = htons(ctl_addr.sin_family);
69#else
70	msg.ctl_addr = *(struct sockaddr *)&ctl_addr;
71#endif
72	/* must be initiating a talk */
73	if (!look_for_invite(rp))
74		return (0);
75	/*
76	 * There was an invitation waiting for us,
77	 * so connect with the other (hopefully waiting) party
78	 */
79	current_state = "Waiting to connect with caller";
80	do {
81		if (rp->addr.sa_family != AF_INET)
82			p_error("Response uses invalid network address");
83		(void)memcpy(&addr, &rp->addr.sa_family, sizeof(addr));
84		addr.sa_family = rp->addr.sa_family;
85		addr.sa_len = sizeof(addr);
86		errno = 0;
87		if (connect(sockt, &addr, sizeof(addr)) != -1)
88			return (1);
89	} while (errno == EINTR);
90	if (errno == ECONNREFUSED) {
91		/*
92		 * The caller gave up, but his invitation somehow
93		 * was not cleared. Clear it and initiate an
94		 * invitation. (We know there are no newer invitations,
95		 * the talkd works LIFO.)
96		 */
97		ctl_transact(his_machine_addr, msg, DELETE, rp);
98		close(sockt);
99		open_sockt();
100		return (0);
101	}
102	p_error("Unable to connect with initiator");
103	/*NOTREACHED*/
104	return (0);
105}
106
107/*
108 * Look for an invitation on 'machine'
109 */
110int
111look_for_invite(rp)
112	CTL_RESPONSE *rp;
113{
114	current_state = "Checking for invitation on caller's machine";
115	ctl_transact(his_machine_addr, msg, LOOK_UP, rp);
116	/* the switch is for later options, such as multiple invitations */
117	switch (rp->answer) {
118
119	case SUCCESS:
120		msg.id_num = htonl(rp->id_num);
121		return (1);
122
123	default:
124		/* there wasn't an invitation waiting for us */
125		return (0);
126	}
127}
128