1 /*        $NetBSD: talkd.h,v 1.11 2016/01/22 23:11:50 dholland Exp $  */
2 
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  *        @(#)talkd.h         8.1 (Berkeley) 6/2/93
32  */
33 
34 #ifndef _PROTOCOLS_TALKD_H_
35 #define   _PROTOCOLS_TALKD_H_
36 
37 #include <stdint.h>
38 
39 /*
40  * This describes the protocol used by the talk server and clients.
41  *
42  * The talk server acts a repository of invitations, responding to
43  * requests by clients wishing to rendezvous for the purpose of
44  * holding a conversation.  In normal operation, a client, the caller,
45  * initiates a rendezvous by sending a CTL_MSG to the server of
46  * type LOOK_UP.  This causes the server to search its invitation
47  * tables to check if an invitation currently exists for the caller
48  * (to speak to the callee specified in the message).  If the lookup
49  * fails, the caller then sends an ANNOUNCE message causing the server
50  * to broadcast an announcement on the callee's login ports requesting
51  * contact.  When the callee responds, the local server uses the
52  * recorded invitation to respond with the appropriate rendezvous
53  * address and the caller and callee client programs establish a
54  * stream connection through which the conversation takes place.
55  */
56 
57 /*
58  * 4.3 compat sockaddr
59  */
60 struct talkd_sockaddr {
61           uint16_t  sa_family;          /* address family */
62           char                sa_data[14];        /* up to 14 bytes of direct address */
63 };
64 
65 /*
66  * Client->server request message format.
67  */
68 typedef struct {
69           unsigned char vers;           /* protocol version */
70           unsigned char type;           /* request type, see below */
71           unsigned char answer;                   /* not used */
72           unsigned char pad;
73           uint32_t id_num;              /* message id */
74           struct      talkd_sockaddr addr;        /* old (4.3) style */
75           struct      talkd_sockaddr ctl_addr;/* old (4.3) style */
76           int32_t     pid;                        /* caller's process id */
77 #define   NAME_SIZE 12
78           char        l_name[NAME_SIZE];          /* caller's name */
79           char        r_name[NAME_SIZE];          /* callee's name */
80 #define   TTY_SIZE  16
81           char        r_tty[TTY_SIZE];  /* callee's tty name */
82 } CTL_MSG;
83 
84 /*
85  * Server->client response message format.
86  */
87 typedef struct {
88           unsigned char vers; /* protocol version */
89           unsigned char type; /* type of request message, see below */
90           unsigned char answer;         /* respose to request message, see below */
91           unsigned char pad;
92           uint32_t id_num;    /* message id */
93           struct      talkd_sockaddr addr; /* address for establishing conversation */
94 } CTL_RESPONSE;
95 
96 #define   TALK_VERSION        1                   /* protocol version */
97 
98 /* message type values */
99 #define LEAVE_INVITE          0         /* leave invitation with server */
100 #define LOOK_UP               1         /* check for invitation by callee */
101 #define DELETE                2         /* delete invitation by caller */
102 #define ANNOUNCE    3         /* announce invitation by caller */
103 
104 /* answer values */
105 #define SUCCESS               0         /* operation completed properly */
106 #define NOT_HERE    1         /* callee not logged in */
107 #define FAILED                2         /* operation failed for unexplained reason */
108 #define MACHINE_UNKNOWN       3         /* caller's machine name unknown */
109 #define PERMISSION_DENIED 4   /* callee's tty doesn't permit announce */
110 #define UNKNOWN_REQUEST       5         /* request has invalid type value */
111 #define   BADVERSION          6         /* request has invalid protocol version */
112 #define   BADADDR             7         /* request has invalid addr value */
113 #define   BADCTLADDR          8         /* request has invalid ctl_addr value */
114 
115 /*
116  * Operational parameters.
117  */
118 #define MAX_LIFE    60        /* max time daemon saves invitations */
119 /* RING_WAIT should be 10's of seconds less than MAX_LIFE */
120 #define RING_WAIT   30        /* time to wait before resending invitation */
121 
122 #endif /* !_PROTOCOLS_TALKD_H_ */
123