1 /* $NetBSD: ppp-comp.h,v 1.8 2002/09/13 14:32:11 itojun Exp $ */ 2 3 /* 4 * ppp-comp.h - Definitions for doing PPP packet compression. 5 * 6 * Copyright (c) 1989-2002 Paul Mackerras. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 20 * 3. The name(s) of the authors of this software must not be used to 21 * endorse or promote products derived from this software without 22 * prior written permission. 23 * 24 * 4. Redistributions of any form whatsoever must retain the following 25 * acknowledgment: 26 * "This product includes software developed by Paul Mackerras 27 * <paulus@samba.org>". 28 * 29 * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO 30 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 31 * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY 32 * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 33 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN 34 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING 35 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 36 */ 37 38 #ifndef _NET_PPP_COMP_H 39 #define _NET_PPP_COMP_H 40 41 /* 42 * The following symbols control whether we include code for 43 * various compression methods. 44 */ 45 #ifndef DO_BSD_COMPRESS 46 #define DO_BSD_COMPRESS 1 /* by default, include BSD-Compress */ 47 #endif 48 #ifndef DO_DEFLATE 49 #define DO_DEFLATE 1 /* by default, include Deflate */ 50 #endif 51 #define DO_PREDICTOR_1 0 52 #define DO_PREDICTOR_2 0 53 54 /* 55 * Structure giving methods for compression/decompression. 56 */ 57 #ifdef PACKETPTR 58 struct compressor { 59 int compress_proto; /* CCP compression protocol number */ 60 61 /* Allocate space for a compressor (transmit side) */ 62 void *(*comp_alloc) __P((u_char *options, int opt_len)); 63 /* Free space used by a compressor */ 64 void (*comp_free) __P((void *state)); 65 /* Initialize a compressor */ 66 int (*comp_init) __P((void *state, u_char *options, int opt_len, 67 int unit, int hdrlen, int debug)); 68 /* Reset a compressor */ 69 void (*comp_reset) __P((void *state)); 70 /* Compress a packet */ 71 int (*compress) __P((void *state, PACKETPTR *mret, 72 PACKETPTR mp, int orig_len, int max_len)); 73 /* Return compression statistics */ 74 void (*comp_stat) __P((void *state, struct compstat *stats)); 75 76 /* Allocate space for a decompressor (receive side) */ 77 void *(*decomp_alloc) __P((u_char *options, int opt_len)); 78 /* Free space used by a decompressor */ 79 void (*decomp_free) __P((void *state)); 80 /* Initialize a decompressor */ 81 int (*decomp_init) __P((void *state, u_char *options, int opt_len, 82 int unit, int hdrlen, int mru, int debug)); 83 /* Reset a decompressor */ 84 void (*decomp_reset) __P((void *state)); 85 /* Decompress a packet. */ 86 int (*decompress) __P((void *state, PACKETPTR mp, 87 PACKETPTR *dmpp)); 88 /* Update state for an incompressible packet received */ 89 void (*incomp) __P((void *state, PACKETPTR mp)); 90 /* Return decompression statistics */ 91 void (*decomp_stat) __P((void *state, struct compstat *stats)); 92 }; 93 #endif /* PACKETPTR */ 94 95 /* 96 * Return values for decompress routine. 97 * We need to make these distinctions so that we can disable certain 98 * useful functionality, namely sending a CCP reset-request as a result 99 * of an error detected after decompression. This is to avoid infringing 100 * a patent held by Motorola. 101 * Don't you just lurve software patents. 102 */ 103 #define DECOMP_OK 0 /* everything went OK */ 104 #define DECOMP_ERROR 1 /* error detected before decomp. */ 105 #define DECOMP_FATALERROR 2 /* error detected after decomp. */ 106 107 /* 108 * CCP codes. 109 */ 110 #define CCP_CONFREQ 1 111 #define CCP_CONFACK 2 112 #define CCP_CONFNAK 3 113 #define CCP_CONFREJ 4 114 #define CCP_TERMREQ 5 115 #define CCP_TERMACK 6 116 #define CCP_RESETREQ 14 117 #define CCP_RESETACK 15 118 119 /* 120 * Max # bytes for a CCP option 121 */ 122 #define CCP_MAX_OPTION_LENGTH 64 123 124 /* 125 * Parts of a CCP packet. 126 */ 127 #define CCP_CODE(dp) ((dp)[0]) 128 #define CCP_ID(dp) ((dp)[1]) 129 #define CCP_LENGTH(dp) (((dp)[2] << 8) + (dp)[3]) 130 #define CCP_HDRLEN 4 131 132 #define CCP_OPT_CODE(dp) ((dp)[0]) 133 #define CCP_OPT_LENGTH(dp) ((dp)[1]) 134 #define CCP_OPT_MINLEN 2 135 136 /* 137 * Definitions for BSD-Compress. 138 */ 139 #define CI_BSD_COMPRESS 21 /* config. option for BSD-Compress */ 140 #define CILEN_BSD_COMPRESS 3 /* length of config. option */ 141 142 /* Macros for handling the 3rd byte of the BSD-Compress config option. */ 143 #define BSD_NBITS(x) ((x) & 0x1F) /* number of bits requested */ 144 #define BSD_VERSION(x) ((x) >> 5) /* version of option format */ 145 #define BSD_CURRENT_VERSION 1 /* current version number */ 146 #define BSD_MAKE_OPT(v, n) (((v) << 5) | (n)) 147 148 #define BSD_MIN_BITS 9 /* smallest code size supported */ 149 #define BSD_MAX_BITS 15 /* largest code size supported */ 150 151 /* 152 * Definitions for Deflate. 153 */ 154 #define CI_DEFLATE 26 /* config option for Deflate */ 155 #define CI_DEFLATE_DRAFT 24 /* value used in original draft RFC */ 156 157 #define CILEN_DEFLATE 4 /* length of its config option */ 158 159 #define DEFLATE_MIN_SIZE 8 160 #define DEFLATE_MAX_SIZE 15 161 #define DEFLATE_METHOD_VAL 8 162 #define DEFLATE_SIZE(x) (((x) >> 4) + DEFLATE_MIN_SIZE) 163 #define DEFLATE_METHOD(x) ((x) & 0x0F) 164 #define DEFLATE_MAKE_OPT(w) ((((w) - DEFLATE_MIN_SIZE) << 4) \ 165 + DEFLATE_METHOD_VAL) 166 #define DEFLATE_CHK_SEQUENCE 0 167 168 /* 169 * Definitions for other, as yet unsupported, compression methods. 170 */ 171 #define CI_PREDICTOR_1 1 /* config option for Predictor-1 */ 172 #define CILEN_PREDICTOR_1 2 /* length of its config option */ 173 #define CI_PREDICTOR_2 2 /* config option for Predictor-2 */ 174 #define CILEN_PREDICTOR_2 2 /* length of its config option */ 175 176 #endif /* _NET_PPP_COMP_H */ 177