File: ppp-comp.h

package info (click to toggle)
ppp 2.4.7-2+4.1
  • links: PTS, VCS
  • area: main
  • in suites: bullseye, buster, sid
  • size: 7,100 kB
  • sloc: ansic: 56,241; sh: 1,050; perl: 334; makefile: 114; exp: 82
file content (158 lines) | stat: -rw-r--r-- 5,373 bytes parent folder | download | duplicates (6)
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
/*
 * ppp-comp.h - Definitions for doing PPP packet compression.
 *
 * Copyright (c) 1994 Paul Mackerras. 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. The name(s) of the authors of this software must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission.
 *
 * 4. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by Paul Mackerras
 *     <paulus@samba.org>".
 *
 * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO
 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
 * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 * $Id: ppp-comp.h,v 1.2 2002/12/06 09:49:16 paulus Exp $
 */

#ifndef _NET_PPP_COMP_H
#define _NET_PPP_COMP_H

/*
 * The following symbols control whether we include code for
 * various compression methods.
 */
#ifndef DO_BSD_COMPRESS
#define DO_BSD_COMPRESS	1	/* by default, include BSD-Compress */
#endif
#ifndef DO_DEFLATE
#define DO_DEFLATE	1	/* by default, include Deflate */
#endif
#define DO_PREDICTOR_1	0
#define DO_PREDICTOR_2	0

/*
 * Structure giving methods for compression/decompression.
 */
struct compressor {
	int	compress_proto;	/* CCP compression protocol number */

	/* Allocate space for a decompressor (receive side) */
	void	*(*decomp_alloc) __P((u_char *options, int opt_len));
	/* Free space used by a decompressor */
	void	(*decomp_free) __P((void *state));
	/* Initialize a decompressor */
	int	(*decomp_init) __P((void *state, u_char *options, int opt_len,
				    int unit, int hdrlen, int mru, int debug));
	/* Reset a decompressor */
	void	(*decomp_reset) __P((void *state));
	/* Decompress a packet. */
	int	(*decompress) __P((void *state, u_char *mp, int inlen,
				   u_char *dmp, int *outlen));
	/* Update state for an incompressible packet received */
	void	(*incomp) __P((void *state, u_char *mp, int len));
	/* Return decompression statistics */
	void	(*decomp_stat) __P((void *state, struct compstat *stats));
};

/*
 * Return values for decompress routine.
 * We need to make these distinctions so that we can disable certain
 * useful functionality, namely sending a CCP reset-request as a result
 * of an error detected after decompression.  This is to avoid infringing
 * a patent held by Motorola.
 * Don't you just lurve software patents.
 */
#define DECOMP_OK		0	/* everything went OK */
#define DECOMP_ERROR		1	/* error detected before decomp. */
#define DECOMP_FATALERROR	2	/* error detected after decomp. */

/*
 * CCP codes.
 */
#define CCP_CONFREQ	1
#define CCP_CONFACK	2
#define CCP_CONFNAK	3
#define CCP_CONFREJ	4
#define CCP_TERMREQ	5
#define CCP_TERMACK	6
#define CCP_RESETREQ	14
#define CCP_RESETACK	15

/*
 * Max # bytes for a CCP option
 */
#define CCP_MAX_OPTION_LENGTH	32

/*
 * Parts of a CCP packet.
 */
#define CCP_CODE(dp)		((dp)[0])
#define CCP_ID(dp)		((dp)[1])
#define CCP_LENGTH(dp)		(((dp)[2] << 8) + (dp)[3])
#define CCP_HDRLEN		4

#define CCP_OPT_CODE(dp)	((dp)[0])
#define CCP_OPT_LENGTH(dp)	((dp)[1])
#define CCP_OPT_MINLEN		2

/*
 * Definitions for BSD-Compress.
 */
#define CI_BSD_COMPRESS		21	/* config. option for BSD-Compress */
#define CILEN_BSD_COMPRESS	3	/* length of config. option */

/* Macros for handling the 3rd byte of the BSD-Compress config option. */
#define BSD_NBITS(x)		((x) & 0x1F)	/* number of bits requested */
#define BSD_VERSION(x)		((x) >> 5)	/* version of option format */
#define BSD_CURRENT_VERSION	1		/* current version number */
#define BSD_MAKE_OPT(v, n)	(((v) << 5) | (n))

#define BSD_MIN_BITS		9	/* smallest code size supported */
#define BSD_MAX_BITS		15	/* largest code size supported */

/*
 * Definitions for Deflate.
 */
#define CI_DEFLATE		26	/* config option for Deflate */
#define CI_DEFLATE_DRAFT	24	/* value used in original draft RFC */
#define CILEN_DEFLATE		4	/* length of its config option */

#define DEFLATE_MIN_SIZE	8
#define DEFLATE_MAX_SIZE	15
#define DEFLATE_METHOD_VAL	8
#define DEFLATE_SIZE(x)		(((x) >> 4) + DEFLATE_MIN_SIZE)
#define DEFLATE_METHOD(x)	((x) & 0x0F)
#define DEFLATE_MAKE_OPT(w)	((((w) - DEFLATE_MIN_SIZE) << 4) \
				 + DEFLATE_METHOD_VAL)
#define DEFLATE_CHK_SEQUENCE	0

/*
 * Definitions for other, as yet unsupported, compression methods.
 */
#define CI_PREDICTOR_1		1	/* config option for Predictor-1 */
#define CILEN_PREDICTOR_1	2	/* length of its config option */
#define CI_PREDICTOR_2		2	/* config option for Predictor-2 */
#define CILEN_PREDICTOR_2	2	/* length of its config option */

#endif /* _NET_PPP_COMP_H */