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