1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2/*
3 * ppp-comp.h - Definitions for doing PPP packet compression.
4 *
5 * Copyright 1994-1998 Paul Mackerras.
6 *
7 *  This program is free software; you can redistribute it and/or
8 *  modify it under the terms of the GNU General Public License
9 *  version 2 as published by the Free Software Foundation.
10 */
11#ifndef _UAPI_NET_PPP_COMP_H
12#define _UAPI_NET_PPP_COMP_H
13
14
15/*
16 * CCP codes.
17 */
18
19#define CCP_CONFREQ	1
20#define CCP_CONFACK	2
21#define CCP_TERMREQ	5
22#define CCP_TERMACK	6
23#define CCP_RESETREQ	14
24#define CCP_RESETACK	15
25
26/*
27 * Max # bytes for a CCP option
28 */
29
30#define CCP_MAX_OPTION_LENGTH	32
31
32/*
33 * Parts of a CCP packet.
34 */
35
36#define CCP_CODE(dp)		((dp)[0])
37#define CCP_ID(dp)		((dp)[1])
38#define CCP_LENGTH(dp)		(((dp)[2] << 8) + (dp)[3])
39#define CCP_HDRLEN		4
40
41#define CCP_OPT_CODE(dp)	((dp)[0])
42#define CCP_OPT_LENGTH(dp)	((dp)[1])
43#define CCP_OPT_MINLEN		2
44
45/*
46 * Definitions for BSD-Compress.
47 */
48
49#define CI_BSD_COMPRESS		21	/* config. option for BSD-Compress */
50#define CILEN_BSD_COMPRESS	3	/* length of config. option */
51
52/* Macros for handling the 3rd byte of the BSD-Compress config option. */
53#define BSD_NBITS(x)		((x) & 0x1F)	/* number of bits requested */
54#define BSD_VERSION(x)		((x) >> 5)	/* version of option format */
55#define BSD_CURRENT_VERSION	1		/* current version number */
56#define BSD_MAKE_OPT(v, n)	(((v) << 5) | (n))
57
58#define BSD_MIN_BITS		9	/* smallest code size supported */
59#define BSD_MAX_BITS		15	/* largest code size supported */
60
61/*
62 * Definitions for Deflate.
63 */
64
65#define CI_DEFLATE		26	/* config option for Deflate */
66#define CI_DEFLATE_DRAFT	24	/* value used in original draft RFC */
67#define CILEN_DEFLATE		4	/* length of its config option */
68
69#define DEFLATE_MIN_SIZE	9
70#define DEFLATE_MAX_SIZE	15
71#define DEFLATE_METHOD_VAL	8
72#define DEFLATE_SIZE(x)		(((x) >> 4) + 8)
73#define DEFLATE_METHOD(x)	((x) & 0x0F)
74#define DEFLATE_MAKE_OPT(w)	((((w) - 8) << 4) + DEFLATE_METHOD_VAL)
75#define DEFLATE_CHK_SEQUENCE	0
76
77/*
78 * Definitions for MPPE.
79 */
80
81#define CI_MPPE                18      /* config option for MPPE */
82#define CILEN_MPPE              6      /* length of config option */
83
84/*
85 * Definitions for other, as yet unsupported, compression methods.
86 */
87
88#define CI_PREDICTOR_1		1	/* config option for Predictor-1 */
89#define CILEN_PREDICTOR_1	2	/* length of its config option */
90#define CI_PREDICTOR_2		2	/* config option for Predictor-2 */
91#define CILEN_PREDICTOR_2	2	/* length of its config option */
92
93
94#endif /* _UAPI_NET_PPP_COMP_H */
95