1/* 2 * ppp-comp.h - Definitions for doing PPP packet compression. 3 * 4 * Copyright (c) 1994 The Australian National University. 5 * All rights reserved. 6 * 7 * Permission to use, copy, modify, and distribute this software and its 8 * documentation is hereby granted, provided that the above copyright 9 * notice appears in all copies. This software is provided without any 10 * warranty, express or implied. The Australian National University 11 * makes no representations about the suitability of this software for 12 * any purpose. 13 * 14 * IN NO EVENT SHALL THE AUSTRALIAN NATIONAL UNIVERSITY BE LIABLE TO ANY 15 * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 16 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF 17 * THE AUSTRALIAN NATIONAL UNIVERSITY HAVE BEEN ADVISED OF THE POSSIBILITY 18 * OF SUCH DAMAGE. 19 * 20 * THE AUSTRALIAN NATIONAL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES, 21 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 22 * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS 23 * ON AN "AS IS" BASIS, AND THE AUSTRALIAN NATIONAL UNIVERSITY HAS NO 24 * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, 25 * OR MODIFICATIONS. 26 * 27 * $Id: ppp-comp.h,v 1.1.1.1 2008/10/15 03:30:13 james26_jang Exp $ 28 */ 29 30#ifndef _NET_PPP_COMP_H 31#define _NET_PPP_COMP_H 32 33/* 34 * The following symbols control whether we include code for 35 * various compression methods. 36 */ 37#ifndef DO_BSD_COMPRESS 38#define DO_BSD_COMPRESS 1 /* by default, include BSD-Compress */ 39#endif 40#ifndef DO_DEFLATE 41#define DO_DEFLATE 1 /* by default, include Deflate */ 42#endif 43#define DO_PREDICTOR_1 0 44#define DO_PREDICTOR_2 0 45 46/* 47 * Structure giving methods for compression/decompression. 48 */ 49struct compressor { 50 int compress_proto; /* CCP compression protocol number */ 51 52 /* Allocate space for a decompressor (receive side) */ 53 void *(*decomp_alloc) __P((u_char *options, int opt_len)); 54 /* Free space used by a decompressor */ 55 void (*decomp_free) __P((void *state)); 56 /* Initialize a decompressor */ 57 int (*decomp_init) __P((void *state, u_char *options, int opt_len, 58 int unit, int hdrlen, int mru, int debug)); 59 /* Reset a decompressor */ 60 void (*decomp_reset) __P((void *state)); 61 /* Decompress a packet. */ 62 int (*decompress) __P((void *state, u_char *mp, int inlen, 63 u_char *dmp, int *outlen)); 64 /* Update state for an incompressible packet received */ 65 void (*incomp) __P((void *state, u_char *mp, int len)); 66 /* Return decompression statistics */ 67 void (*decomp_stat) __P((void *state, struct compstat *stats)); 68}; 69 70/* 71 * Return values for decompress routine. 72 * We need to make these distinctions so that we can disable certain 73 * useful functionality, namely sending a CCP reset-request as a result 74 * of an error detected after decompression. This is to avoid infringing 75 * a patent held by Motorola. 76 * Don't you just lurve software patents. 77 */ 78#define DECOMP_OK 0 /* everything went OK */ 79#define DECOMP_ERROR 1 /* error detected before decomp. */ 80#define DECOMP_FATALERROR 2 /* error detected after decomp. */ 81 82/* 83 * CCP codes. 84 */ 85#define CCP_CONFREQ 1 86#define CCP_CONFACK 2 87#define CCP_CONFNAK 3 88#define CCP_CONFREJ 4 89#define CCP_TERMREQ 5 90#define CCP_TERMACK 6 91#define CCP_RESETREQ 14 92#define CCP_RESETACK 15 93 94/* 95 * Max # bytes for a CCP option 96 */ 97#define CCP_MAX_OPTION_LENGTH 32 98 99/* 100 * Parts of a CCP packet. 101 */ 102#define CCP_CODE(dp) ((dp)[0]) 103#define CCP_ID(dp) ((dp)[1]) 104#define CCP_LENGTH(dp) (((dp)[2] << 8) + (dp)[3]) 105#define CCP_HDRLEN 4 106 107#define CCP_OPT_CODE(dp) ((dp)[0]) 108#define CCP_OPT_LENGTH(dp) ((dp)[1]) 109#define CCP_OPT_MINLEN 2 110 111/* 112 * Definitions for BSD-Compress. 113 */ 114#define CI_BSD_COMPRESS 21 /* config. option for BSD-Compress */ 115#define CILEN_BSD_COMPRESS 3 /* length of config. option */ 116 117/* Macros for handling the 3rd byte of the BSD-Compress config option. */ 118#define BSD_NBITS(x) ((x) & 0x1F) /* number of bits requested */ 119#define BSD_VERSION(x) ((x) >> 5) /* version of option format */ 120#define BSD_CURRENT_VERSION 1 /* current version number */ 121#define BSD_MAKE_OPT(v, n) (((v) << 5) | (n)) 122 123#define BSD_MIN_BITS 9 /* smallest code size supported */ 124#define BSD_MAX_BITS 15 /* largest code size supported */ 125 126/* 127 * Definitions for Deflate. 128 */ 129#define CI_DEFLATE 26 /* config option for Deflate */ 130#define CI_DEFLATE_DRAFT 24 /* value used in original draft RFC */ 131#define CILEN_DEFLATE 4 /* length of its config option */ 132 133#define DEFLATE_MIN_SIZE 8 134#define DEFLATE_MAX_SIZE 15 135#define DEFLATE_METHOD_VAL 8 136#define DEFLATE_SIZE(x) (((x) >> 4) + DEFLATE_MIN_SIZE) 137#define DEFLATE_METHOD(x) ((x) & 0x0F) 138#define DEFLATE_MAKE_OPT(w) ((((w) - DEFLATE_MIN_SIZE) << 4) \ 139 + DEFLATE_METHOD_VAL) 140#define DEFLATE_CHK_SEQUENCE 0 141 142/* 143 * Definitions for other, as yet unsupported, compression methods. 144 */ 145#define CI_PREDICTOR_1 1 /* config option for Predictor-1 */ 146#define CILEN_PREDICTOR_1 2 /* length of its config option */ 147#define CI_PREDICTOR_2 2 /* config option for Predictor-2 */ 148#define CILEN_PREDICTOR_2 2 /* length of its config option */ 149 150#endif /* _NET_PPP_COMP_H */ 151