215 lines
6.5 KiB
C
215 lines
6.5 KiB
C
/*
|
|
* 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.
|
|
*/
|
|
|
|
/*
|
|
* ==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 */
|