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Diffstat (limited to 'include/linux/ppp-comp.h')
| -rw-r--r-- | include/linux/ppp-comp.h | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/include/linux/ppp-comp.h b/include/linux/ppp-comp.h new file mode 100644 index 00000000000..7227e653b3b --- /dev/null +++ b/include/linux/ppp-comp.h @@ -0,0 +1,207 @@ +/* + * 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; +}; + +/* + * 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 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 */ |