1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
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
33
34 #include <sys/types.h>
35 #include <sys/socket.h>
36 #include <protocols/talkd.h>
37
38 #include <errno.h>
39 #include <string.h>
40 #include <unistd.h>
41
42 #include "talk_ctl.h"
43 #include "talk.h"
44
45 /*
46 * See if the local daemon has an invitation for us.
47 */
48 int
check_local(void)49 check_local(void)
50 {
51 CTL_RESPONSE response;
52 CTL_RESPONSE *rp = &response;
53 struct sockaddr addr;
54
55 /* the rest of msg was set up in get_names */
56 /* copy new style sockaddr to old, swap family (short in old) */
57 msg.ctl_addr = *(struct tsockaddr *)&ctl_addr;
58 msg.ctl_addr.sa_family = htons(ctl_addr.sin_family);
59 /* must be initiating a talk */
60 if (!look_for_invite(rp))
61 return (0);
62 /*
63 * There was an invitation waiting for us,
64 * so connect with the other (hopefully waiting) party
65 */
66 current_state = "Waiting to connect with caller";
67 do {
68 if (rp->addr.sa_family != AF_INET)
69 p_error("Response uses invalid network address");
70 (void)memcpy(&addr, &rp->addr.sa_family, sizeof(addr));
71 addr.sa_family = rp->addr.sa_family;
72 addr.sa_len = sizeof(addr);
73 errno = 0;
74 if (connect(sockt, &addr, sizeof(addr)) != -1)
75 return (1);
76 } while (errno == EINTR);
77 if (errno == ECONNREFUSED) {
78 /*
79 * The caller gave up, but his invitation somehow
80 * was not cleared. Clear it and initiate an
81 * invitation. (We know there are no newer invitations,
82 * the talkd works LIFO.)
83 */
84 ctl_transact(his_machine_addr, msg, DELETE, rp);
85 close(sockt);
86 open_sockt();
87 return (0);
88 }
89 p_error("Unable to connect with initiator");
90 /*NOTREACHED*/
91 return (0);
92 }
93
94 /*
95 * Look for an invitation on 'machine'
96 */
97 int
look_for_invite(CTL_RESPONSE * rp)98 look_for_invite(CTL_RESPONSE *rp)
99 {
100 current_state = "Checking for invitation on caller's machine";
101 ctl_transact(his_machine_addr, msg, LOOK_UP, rp);
102 /* the switch is for later options, such as multiple invitations */
103 switch (rp->answer) {
104
105 case SUCCESS:
106 msg.id_num = htonl(rp->id_num);
107 return (1);
108
109 default:
110 /* there wasn't an invitation waiting for us */
111 return (0);
112 }
113 }
114