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 1999/03/23 03:21:58 paulus 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 */ 49 struct 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