talkd.h revision 25551 
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 *	@(#)talkd.h	8.1 (Berkeley) 6/2/93
34 */
35
36#ifndef _PROTOCOLS_TALKD_H_
37#define	_PROTOCOLS_TALKD_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 * Client->server request message format.
59 */
60typedef struct {
61	u_char	vers;		/* protocol version */
62	u_char	type;		/* request type, see below */
63	u_char	answer;		/* not used */
64	u_char	pad;
65	u_long	id_num;		/* message id */
66	struct	osockaddr addr;		/* old (4.3) style */
67	struct	osockaddr ctl_addr;	/* old (4.3) style */
68	long	pid;		/* caller's process id */
69#define	NAME_SIZE	12
70	char	l_name[NAME_SIZE];/* caller's name */
71	char	r_name[NAME_SIZE];/* callee's name */
72#define	TTY_SIZE	16
73	char	r_tty[TTY_SIZE];/* callee's tty name */
74} CTL_MSG;
75
76/*
77 * Server->client response message format.
78 */
79typedef struct {
80	u_char	vers;		/* protocol version */
81	u_char	type;		/* type of request message, see below */
82	u_char	answer;		/* respose to request message, see below */
83	u_char	pad;
84	u_long	id_num;		/* message id */
85	struct	osockaddr addr;	/* address for establishing conversation */
86} CTL_RESPONSE;
87
88#define	TALK_VERSION	1		/* protocol version */
89
90/* message type values */
91#define LEAVE_INVITE	0	/* leave invitation with server */
92#define LOOK_UP		1	/* check for invitation by callee */
93#define DELETE		2	/* delete invitation by caller */
94#define ANNOUNCE	3	/* announce invitation by caller */
95
96/* answer values */
97#define SUCCESS		0	/* operation completed properly */
98#define NOT_HERE	1	/* callee not logged in */
99#define FAILED		2	/* operation failed for unexplained reason */
100#define MACHINE_UNKNOWN	3	/* caller's machine name unknown */
101#define PERMISSION_DENIED 4	/* callee's tty doesn't permit announce */
102#define UNKNOWN_REQUEST	5	/* request has invalid type value */
103#define	BADVERSION	6	/* request has invalid protocol version */
104#define	BADADDR		7	/* request has invalid addr value */
105#define	BADCTLADDR	8	/* request has invalid ctl_addr value */
106
107/*
108 * Operational parameters.
109 */
110#define MAX_LIFE	60	/* max time daemon saves invitations */
111/* RING_WAIT should be 10's of seconds less than MAX_LIFE */
112#define RING_WAIT	30	/* time to wait before resending invitation */
113
114#endif /* !_TALKD_H_ */
115