xref: /openbsd/usr.bin/talk/invite.c (revision 1037abb8)
1 /*	$OpenBSD: invite.c,v 1.7 1999/03/03 20:43:30 millert Exp $	*/
2 /*	$NetBSD: invite.c,v 1.3 1994/12/09 02:14:18 jtc Exp $	*/
3 
4 /*
5  * Copyright (c) 1983, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 #if 0
39 static char sccsid[] = "@(#)invite.c	8.1 (Berkeley) 6/6/93";
40 #endif
41 static char rcsid[] = "$OpenBSD: invite.c,v 1.7 1999/03/03 20:43:30 millert Exp $";
42 #endif /* not lint */
43 
44 #include "talk.h"
45 #include <arpa/inet.h>
46 #include <sys/time.h>
47 #include <signal.h>
48 #include <netdb.h>
49 #include <errno.h>
50 #include <setjmp.h>
51 #include <unistd.h>
52 #include "talk_ctl.h"
53 
54 #define STRING_LENGTH 158
55 
56 /*
57  * There wasn't an invitation waiting, so send a request containing
58  * our sockt address to the remote talk daemon so it can invite
59  * him
60  */
61 
62 /*
63  * The msg.id's for the invitations
64  * on the local and remote machines.
65  * These are used to delete the
66  * invitations.
67  */
68 int	local_id, remote_id;
69 jmp_buf invitebuf;
70 
71 void
72 invite_remote()
73 {
74 	int new_sockt;
75 	struct itimerval itimer;
76 	CTL_RESPONSE response;
77 	struct sockaddr rp;
78 	int rplen = sizeof(struct sockaddr);
79 	struct hostent *rphost;
80 	char rname[STRING_LENGTH];
81 
82 	itimer.it_value.tv_sec = RING_WAIT;
83 	itimer.it_value.tv_usec = 0;
84 	itimer.it_interval = itimer.it_value;
85 	if (listen(sockt, 5) != 0)
86 		quit("Error on attempt to listen for caller", 1);
87 #ifdef MSG_EOR
88 	/* copy new style sockaddr to old, swap family (short in old) */
89 	msg.addr = *(struct osockaddr *)&my_addr;  /* XXX new to old  style*/
90 	msg.addr.sa_family = htons(my_addr.sin_family);
91 #else
92 	msg.addr = *(struct sockaddr *)&my_addr;
93 #endif
94 	msg.id_num = htonl(-1);		/* an impossible id_num */
95 	invitation_waiting = 1;
96 	announce_invite();
97 	/*
98 	 * Shut off the automatic messages for a while,
99 	 * so we can use the interrupt timer to resend the invitation.
100 	 * We no longer turn automatic messages back on to avoid a bonus
101 	 * message after we've connected; this is okay even though end_msgs()
102 	 * gets called again in main().
103 	 */
104 	end_msgs();
105 	setitimer(ITIMER_REAL, &itimer, (struct itimerval *)0);
106 	message("Waiting for your party to respond");
107 	signal(SIGALRM, re_invite);
108 	(void) setjmp(invitebuf);
109 	while ((new_sockt = accept(sockt, &rp, &rplen)) < 0) {
110 		if (errno == EINTR)
111 			continue;
112 		quit("Unable to connect with your party", 1);
113 	}
114 	close(sockt);
115 	sockt = new_sockt;
116 
117 	/*
118 	 * Have the daemons delete the invitations now that we
119 	 * have connected.
120 	 */
121 	msg.id_num = htonl(local_id);
122 	ctl_transact(my_machine_addr, msg, DELETE, &response);
123 	msg.id_num = htonl(remote_id);
124 	ctl_transact(his_machine_addr, msg, DELETE, &response);
125 	invitation_waiting = 0;
126 
127 	/*
128 	 * Check to see if the other guy is coming from the machine
129 	 * we expect.
130 	 */
131 	if (his_machine_addr.s_addr !=
132 	    ((struct sockaddr_in *)&rp)->sin_addr.s_addr) {
133 		rphost = gethostbyaddr((char *) &((struct sockaddr_in
134 		    *)&rp)->sin_addr, sizeof(struct in_addr), AF_INET);
135 		if (rphost)
136 			snprintf(rname, STRING_LENGTH,
137 			    "Answering talk request from %s@%s", msg.r_name,
138 			    rphost->h_name);
139 		else
140 			snprintf(rname, STRING_LENGTH,
141 			    "Answering talk request from %s@%s", msg.r_name,
142 			    inet_ntoa(((struct sockaddr_in *)&rp)->sin_addr));
143 		message(rname);
144 	}
145 }
146 
147 /*
148  * Routine called on interupt to re-invite the callee
149  */
150 void
151 re_invite(dummy)
152 	int dummy;
153 {
154 	message("Ringing your party again");
155 	/* force a re-announce */
156 	msg.id_num = htonl(remote_id + 1);
157 	announce_invite();
158 	longjmp(invitebuf, 1);
159 }
160 
161 static	char *answers[] = {
162 	"answer #0",					/* SUCCESS */
163 	"Your party is not logged on",			/* NOT_HERE */
164 	"Target machine is too confused to talk to us",	/* FAILED */
165 	"Target machine does not recognize us",		/* MACHINE_UNKNOWN */
166 	"Your party is refusing messages",		/* PERMISSION_REFUSED */
167 	"Target machine can not handle remote talk",	/* UNKNOWN_REQUEST */
168 	"Target machine indicates protocol mismatch",	/* BADVERSION */
169 	"Target machine indicates protocol botch (addr)",/* BADADDR */
170 	"Target machine indicates protocol botch (ctl_addr)",/* BADCTLADDR */
171 };
172 #define NANSWERS (sizeof (answers) / sizeof (answers[0]))
173 
174 /*
175  * Transmit the invitation and process the response
176  */
177 void
178 announce_invite()
179 {
180 	CTL_RESPONSE response;
181 
182 	current_state = "Trying to connect to your party's talk daemon";
183 	ctl_transact(his_machine_addr, msg, ANNOUNCE, &response);
184 	remote_id = response.id_num;
185 	if (response.answer != SUCCESS)
186 		quit(response.answer < NANSWERS ? answers[response.answer] : NULL, 0);
187 	/* leave the actual invitation on my talk daemon */
188 	ctl_transact(my_machine_addr, msg, LEAVE_INVITE, &response);
189 	local_id = response.id_num;
190 }
191 
192 /*
193  * Tell the daemon to remove your invitation
194  */
195 void
196 send_delete()
197 {
198 
199 	msg.type = DELETE;
200 	/*
201 	 * This is just a extra clean up, so just send it
202 	 * and don't wait for an answer
203 	 */
204 	msg.id_num = htonl(remote_id);
205 	daemon_addr.sin_addr = his_machine_addr;
206 	if (sendto(ctl_sockt, &msg, sizeof (msg), 0,
207 	    (struct sockaddr *)&daemon_addr,
208 	    sizeof (daemon_addr)) != sizeof(msg))
209 		warn("send_delete (remote)");
210 	msg.id_num = htonl(local_id);
211 	daemon_addr.sin_addr = my_machine_addr;
212 	if (sendto(ctl_sockt, &msg, sizeof (msg), 0,
213 	    (struct sockaddr *)&daemon_addr,
214 	    sizeof (daemon_addr)) != sizeof (msg))
215 		warn("send_delete (local)");
216 }
217