summaryrefslogtreecommitdiff
path: root/usr.bin/tn3270/api/api_exch.h
blob: c2e6f27f0d6122442fae2bad24fc4c5bd35c35b1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
/* *	$OpenBSD: api_exch.h,v 1.2 1996/06/26 05:41:01 deraadt Exp $*/
/*-
 * Copyright (c) 1988 The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	from: @(#)api_exch.h	4.2 (Berkeley) 4/26/91
 */

/*
 * This file describes the structures passed back and forth
 * between the API client and API server on a Unix-based
 * tn3270 implementation.
 */

/*
 * The following are the low-level opcodes exchanged between the
 * two sides.  These are designed to allow for type, sequence number,
 * and direction checking.
 *
 * We enforce conversation flow.  There are three states: CONTENTION,
 * SEND, and RECEIVE.  Both sides start in CONTENTION.
 * We never leave RECEIVE state without first reading a TURNAROUND
 * opcode.  We never leave SEND state without first writing a TURNAROUND
 * opcode.  This scheme ensures that we always have conversation flowing
 * in a synchronized direction (or detect an application error), and that
 * we never hang with both sides trying to read from the "wire".
 *
 * State	event			action
 *
 * CONTENTION	read request		send TURNAROUND
 *					read RTS
 *					enter RECEIVE
 * CONTENTION	write request		send RTS
 *					read TURNAROUND
 *					enter SEND
 *
 * RECEIVE	read request		read whatever
 * RECEIVE	write request		read TURNAROUND
 *
 * SEND		read request		send TURNAROUND
 * SEND		write			write whatever
 */

#define	EXCH_EXCH_COMMAND	0	/* The following is a command */
#define	EXCH_EXCH_TURNAROUND	1	/* Your turn to send */
#define	EXCH_EXCH_RTS		2	/* Request to send */
#define	EXCH_EXCH_TYPE		3	/* The following is a type */

struct exch_exch {
    char
	opcode;			/* COMMAND, TURNAROUND, or TYPE */
    unsigned char
	my_sequence,		/* 0-ff, initially zero */
	your_sequence,		/* 0-ff, initially zero */
	command_or_type;	/* Application level command or type */
    unsigned short
	length;			/* The length of any following data */
};

/*
 * The following are the command codes which the higher level protocols
 * send and receive.
 */

#define	EXCH_CMD_ASSOCIATE	0	/* Connect [client->server] */
	/*
	 * struct storage_desc
	 * char key[]
	 */
#define	EXCH_CMD_DISASSOCIATE	1	/* Disconnect [client->server] */
#define	EXCH_CMD_SEND_AUTH	2	/* Send password [server->client] */
	/*
	 * struct storage_desc
	 * char prompt[]
	 * struct storage_desc
	 * char seed[]
	 */
#define	EXCH_CMD_AUTH		3	/* Authorization [client->server] */
	/*
	 * struct storage_desc
	 * char authenticator[]
	 */
#define	EXCH_CMD_ASSOCIATED	4	/* Connected [server->client] */
#define	EXCH_CMD_REJECTED	5	/* Too bad [server->client] */
	/*
	 * struct storage_desc
	 * char message[]
	 */

#define	EXCH_CMD_REQUEST	6	/* A request [client->server] */
	/* struct regs,
	 * struct sregs,
	 * struct storage_desc
	 * char bytes[]
	 */
#define	EXCH_CMD_GIMME		7	/* Send storage [server->client] */
	/*
	 * struct storage_desc
	 */
#define	EXCH_CMD_HEREIS		8	/* Here is storage [BOTH WAYS] */
	/*
	 * struct storage_desc
	 * char bytes[]
	 */
#define	EXCH_CMD_REPLY		9	/* End of discussion */
	/*
	 * struct regs,
	 * struct sregs,
	 */

/*
 * The following are typed parameters sent across the wire.
 *
 * This should be done much more generally, with some form of
 * XDR or mapped conversation ability.
 */

#define	EXCH_TYPE_REGS		0
#define	EXCH_TYPE_SREGS		1
#define	EXCH_TYPE_STORE_DESC	2
#define	EXCH_TYPE_BYTES		3

/*
 * each parameter that comes over looks like:
 *
 *	char			type of following
 *	short (2 bytes)		length of following (network byte order)
 *	following
 */

struct storage_descriptor {
    long	location;	/* In network byte order */
    short	length;		/* In network byte order */
};