1 /* $OpenBSD: invite.c,v 1.12 2004/03/02 21:04:42 tedu 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. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)invite.c 8.1 (Berkeley) 6/6/93";
36 #endif
37 static const char rcsid[] = "$OpenBSD: invite.c,v 1.12 2004/03/02 21:04:42 tedu Exp $";
38 #endif /* not lint */
39
40 #include "talk.h"
41 #include <arpa/inet.h>
42 #include <sys/time.h>
43 #include <netdb.h>
44 #include <errno.h>
45 #include <setjmp.h>
46 #include <unistd.h>
47 #include "talk_ctl.h"
48
49 #define STRING_LENGTH 158
50
51 /*
52 * There wasn't an invitation waiting, so send a request containing
53 * our sockt address to the remote talk daemon so it can invite
54 * him
55 */
56
57 /*
58 * The msg.id's for the invitations
59 * on the local and remote machines.
60 * These are used to delete the
61 * invitations.
62 */
63 int local_id, remote_id;
64 jmp_buf invitebuf;
65
66 void
invite_remote(void)67 invite_remote(void)
68 {
69 int new_sockt;
70 struct itimerval itimer;
71 CTL_RESPONSE response;
72 struct sockaddr rp;
73 socklen_t rplen = sizeof(struct sockaddr);
74 struct hostent *rphost;
75 char rname[STRING_LENGTH];
76
77 itimer.it_value.tv_sec = RING_WAIT;
78 itimer.it_value.tv_usec = 0;
79 itimer.it_interval = itimer.it_value;
80 if (listen(sockt, 5) != 0)
81 quit("Error on attempt to listen for caller", 1);
82 #ifdef MSG_EOR
83 /* copy new style sockaddr to old, swap family (short in old) */
84 msg.addr = *(struct osockaddr *)&my_addr; /* XXX new to old style*/
85 msg.addr.sa_family = htons(my_addr.sin_family);
86 #else
87 msg.addr = *(struct sockaddr *)&my_addr;
88 #endif
89 msg.id_num = htonl(-1); /* an impossible id_num */
90 invitation_waiting = 1;
91 announce_invite();
92 /*
93 * Shut off the automatic messages for a while,
94 * so we can use the interrupt timer to resend the invitation.
95 * We no longer turn automatic messages back on to avoid a bonus
96 * message after we've connected; this is okay even though end_msgs()
97 * gets called again in main().
98 */
99 end_msgs();
100 setitimer(ITIMER_REAL, &itimer, (struct itimerval *)0);
101 message("Waiting for your party to respond");
102 signal(SIGALRM, re_invite);
103 (void) setjmp(invitebuf);
104 while ((new_sockt = accept(sockt, &rp, &rplen)) == -1) {
105 if (errno == EINTR || errno == ECONNABORTED)
106 continue;
107 quit("Unable to connect with your party", 1);
108 }
109 close(sockt);
110 sockt = new_sockt;
111
112 /*
113 * Have the daemons delete the invitations now that we
114 * have connected.
115 */
116 msg.id_num = htonl(local_id);
117 ctl_transact(my_machine_addr, msg, DELETE, &response);
118 msg.id_num = htonl(remote_id);
119 ctl_transact(his_machine_addr, msg, DELETE, &response);
120 invitation_waiting = 0;
121
122 /*
123 * Check to see if the other guy is coming from the machine
124 * we expect.
125 */
126 if (his_machine_addr.s_addr !=
127 ((struct sockaddr_in *)&rp)->sin_addr.s_addr) {
128 rphost = gethostbyaddr((char *) &((struct sockaddr_in
129 *)&rp)->sin_addr, sizeof(struct in_addr), AF_INET);
130 if (rphost)
131 snprintf(rname, STRING_LENGTH,
132 "Answering talk request from %s@%s", msg.r_name,
133 rphost->h_name);
134 else
135 snprintf(rname, STRING_LENGTH,
136 "Answering talk request from %s@%s", msg.r_name,
137 inet_ntoa(((struct sockaddr_in *)&rp)->sin_addr));
138 message(rname);
139 }
140 }
141
142 /*
143 * Routine called on interupt to re-invite the callee
144 */
145 void
re_invite(int dummy)146 re_invite(int dummy)
147 {
148 message("Ringing your party again");
149 /* force a re-announce */
150 msg.id_num = htonl(remote_id + 1);
151 announce_invite();
152 longjmp(invitebuf, 1);
153 }
154
155 static char *answers[] = {
156 "answer #0", /* SUCCESS */
157 "Your party is not logged on", /* NOT_HERE */
158 "Target machine is too confused to talk to us", /* FAILED */
159 "Target machine does not recognize us", /* MACHINE_UNKNOWN */
160 "Your party is refusing messages", /* PERMISSION_REFUSED */
161 "Target machine can not handle remote talk", /* UNKNOWN_REQUEST */
162 "Target machine indicates protocol mismatch", /* BADVERSION */
163 "Target machine indicates protocol botch (addr)",/* BADADDR */
164 "Target machine indicates protocol botch (ctl_addr)",/* BADCTLADDR */
165 };
166 #define NANSWERS (sizeof (answers) / sizeof (answers[0]))
167
168 /*
169 * Transmit the invitation and process the response
170 */
171 void
announce_invite(void)172 announce_invite(void)
173 {
174 CTL_RESPONSE response;
175
176 current_state = "Trying to connect to your party's talk daemon";
177 ctl_transact(his_machine_addr, msg, ANNOUNCE, &response);
178 remote_id = response.id_num;
179 if (response.answer != SUCCESS)
180 quit(response.answer < NANSWERS ? answers[response.answer] : NULL, 0);
181 /* leave the actual invitation on my talk daemon */
182 ctl_transact(my_machine_addr, msg, LEAVE_INVITE, &response);
183 local_id = response.id_num;
184 }
185
186 /*
187 * Tell the daemon to remove your invitation
188 */
189 void
send_delete(void)190 send_delete(void)
191 {
192
193 msg.type = DELETE;
194 /*
195 * This is just a extra clean up, so just send it
196 * and don't wait for an answer
197 */
198 msg.id_num = htonl(remote_id);
199 daemon_addr.sin_addr = his_machine_addr;
200 if (sendto(ctl_sockt, &msg, sizeof (msg), 0,
201 (struct sockaddr *)&daemon_addr,
202 sizeof (daemon_addr)) != sizeof(msg))
203 warn("send_delete (remote)");
204 msg.id_num = htonl(local_id);
205 daemon_addr.sin_addr = my_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 (local)");
210 }
211