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
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
|
/*
* ppp-comp.h - Definitions for doing PPP packet compression.
*
* Copyright (c) 1994 The Australian National University.
* All rights reserved.
*
* Permission to use, copy, modify, and distribute this software and its
* documentation is hereby granted, provided that the above copyright
* notice appears in all copies. This software is provided without any
* warranty, express or implied. The Australian National University
* makes no representations about the suitability of this software for
* any purpose.
*
* IN NO EVENT SHALL THE AUSTRALIAN NATIONAL UNIVERSITY BE LIABLE TO ANY
* PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
* THE AUSTRALIAN NATIONAL UNIVERSITY HAVE BEEN ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* THE AUSTRALIAN NATIONAL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE AUSTRALIAN NATIONAL UNIVERSITY HAS NO
* OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,
* OR MODIFICATIONS.
*
* $Id: ppp-comp.h,v 1.6 1997/11/27 06:04:44 paulus Exp $
*/
/*
* ==FILEVERSION 980319==
*
* NOTE TO MAINTAINERS:
* If you modify this file at all, please set the above date.
* ppp-comp.h is shipped with a PPP distribution as well as with the kernel;
* if everyone increases the FILEVERSION number above, then scripts
* can do the right thing when deciding whether to install a new ppp-comp.h
* file. Don't change the format of that line otherwise, so the
* installation script can recognize it.
*/
#ifndef _NET_PPP_COMP_H
#define _NET_PPP_COMP_H
struct module;
/*
* 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 compressor (transmit side) */
void *(*comp_alloc) (unsigned char *options, int opt_len);
/* Free space used by a compressor */
void (*comp_free) (void *state);
/* Initialize a compressor */
int (*comp_init) (void *state, unsigned char *options,
int opt_len, int unit, int opthdr, int debug);
/* Reset a compressor */
void (*comp_reset) (void *state);
/* Compress a packet */
int (*compress) (void *state, unsigned char *rptr,
unsigned char *obuf, int isize, int osize);
/* Return compression statistics */
void (*comp_stat) (void *state, struct compstat *stats);
/* Allocate space for a decompressor (receive side) */
void *(*decomp_alloc) (unsigned char *options, int opt_len);
/* Free space used by a decompressor */
void (*decomp_free) (void *state);
/* Initialize a decompressor */
int (*decomp_init) (void *state, unsigned char *options,
int opt_len, int unit, int opthdr, int mru,
int debug);
/* Reset a decompressor */
void (*decomp_reset) (void *state);
/* Decompress a packet. */
int (*decompress) (void *state, unsigned char *ibuf, int isize,
unsigned char *obuf, int osize);
/* Update state for an incompressible packet received */
void (*incomp) (void *state, unsigned char *ibuf, int icnt);
/* Return decompression statistics */
void (*decomp_stat) (void *state, struct compstat *stats);
/* Used in locking compressor modules */
struct module *owner;
/* Extra skb space needed by the compressor algorithm */
unsigned int comp_extra;
};
/*
* The return value from decompress routine is the length of the
* decompressed packet if successful, otherwise DECOMP_ERROR
* or DECOMP_FATALERROR if an error occurred.
*
* We need to make this distinction 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_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_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 9
#define DEFLATE_MAX_SIZE 15
#define DEFLATE_METHOD_VAL 8
#define DEFLATE_SIZE(x) (((x) >> 4) + 8)
#define DEFLATE_METHOD(x) ((x) & 0x0F)
#define DEFLATE_MAKE_OPT(w) ((((w) - 8) << 4) + DEFLATE_METHOD_VAL)
#define DEFLATE_CHK_SEQUENCE 0
/*
* Definitions for MPPE.
*/
#define CI_MPPE 18 /* config option for MPPE */
#define CILEN_MPPE 6 /* length of config option */
/*
* 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 */
#ifdef __KERNEL__
extern int ppp_register_compressor(struct compressor *);
extern void ppp_unregister_compressor(struct compressor *);
#endif /* __KERNEL__ */
#endif /* _NET_PPP_COMP_H */
|
