xref: /freebsd/include/protocols/talkd.h (revision a0ee8cc6)
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. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  *	@(#)talkd.h	8.1 (Berkeley) 6/2/93
30  *
31  * $FreeBSD$
32  */
33 
34 #ifndef _PROTOCOLS_TALKD_H_
35 #define	_PROTOCOLS_TALKD_H_
36 
37 /*
38  * This describes the protocol used by the talk server and clients.
39  *
40  * The talk server acts a repository of invitations, responding to
41  * requests by clients wishing to rendezvous for the purpose of
42  * holding a conversation.  In normal operation, a client, the caller,
43  * initiates a rendezvous by sending a CTL_MSG to the server of
44  * type LOOK_UP.  This causes the server to search its invitation
45  * tables to check if an invitation currently exists for the caller
46  * (to speak to the callee specified in the message).  If the lookup
47  * fails, the caller then sends an ANNOUNCE message causing the server
48  * to broadcast an announcement on the callee's login ports requesting
49  * contact.  When the callee responds, the local server uses the
50  * recorded invitation to respond with the appropriate rendezvous
51  * address and the caller and callee client programs establish a
52  * stream connection through which the conversation takes place.
53  */
54 
55 /*
56  * Client->server request message format.
57  */
58 typedef struct {
59 	u_char	vers;		/* protocol version */
60 	u_char	type;		/* request type, see below */
61 	u_char	answer;		/* not used */
62 	u_char	pad;
63 	u_int32_t	id_num;		/* message id */
64 	struct	osockaddr addr;		/* old (4.3) style */
65 	struct	osockaddr ctl_addr;	/* old (4.3) style */
66 	int32_t	pid;		/* caller's process id */
67 #define	NAME_SIZE	12
68 	char	l_name[NAME_SIZE];/* caller's name */
69 	char	r_name[NAME_SIZE];/* callee's name */
70 #define	TTY_SIZE	16
71 	char	r_tty[TTY_SIZE];/* callee's tty name */
72 } CTL_MSG;
73 
74 /*
75  * Server->client response message format.
76  */
77 typedef struct {
78 	u_char	vers;		/* protocol version */
79 	u_char	type;		/* type of request message, see below */
80 	u_char	answer;		/* respose to request message, see below */
81 	u_char	pad;
82 	u_int32_t	id_num;		/* message id */
83 	struct	osockaddr addr;	/* address for establishing conversation */
84 } CTL_RESPONSE;
85 
86 #define	TALK_VERSION	1		/* protocol version */
87 
88 /* message type values */
89 #define LEAVE_INVITE	0	/* leave invitation with server */
90 #define LOOK_UP		1	/* check for invitation by callee */
91 #define DELETE		2	/* delete invitation by caller */
92 #define ANNOUNCE	3	/* announce invitation by caller */
93 
94 /* answer values */
95 #define SUCCESS		0	/* operation completed properly */
96 #define NOT_HERE	1	/* callee not logged in */
97 #define FAILED		2	/* operation failed for unexplained reason */
98 #define MACHINE_UNKNOWN	3	/* caller's machine name unknown */
99 #define PERMISSION_DENIED 4	/* callee's tty doesn't permit announce */
100 #define UNKNOWN_REQUEST	5	/* request has invalid type value */
101 #define	BADVERSION	6	/* request has invalid protocol version */
102 #define	BADADDR		7	/* request has invalid addr value */
103 #define	BADCTLADDR	8	/* request has invalid ctl_addr value */
104 
105 /*
106  * Operational parameters.
107  */
108 #define MAX_LIFE	60	/* max time daemon saves invitations */
109 /* RING_WAIT should be 10's of seconds less than MAX_LIFE */
110 #define RING_WAIT	30	/* time to wait before resending invitation */
111 
112 #endif /* !_TALKD_H_ */
113