1 /* $NetBSD: ppp-comp.h,v 1.16 2008/11/29 23:15:20 cube 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 * How many entries to make available in the compressors table 56 */ 57 #ifndef PPP_COMPRESSORS_MAX 58 #define PPP_COMPRESSORS_MAX 8 59 #endif 60 61 /* 62 * Structure giving methods for compression/decompression. 63 */ 64 #ifdef PACKETPTR 65 #include <sys/queue.h> 66 67 struct compressor { 68 int compress_proto; /* CCP compression protocol number */ 69 70 /* Allocate space for a compressor (transmit side) */ 71 void *(*comp_alloc)(u_char *, int); 72 /* Free space used by a compressor */ 73 void (*comp_free)(void *); 74 /* Initialize a compressor */ 75 int (*comp_init)(void *, u_char *, int, int, int, int); 76 /* Reset a compressor */ 77 void (*comp_reset)(void *); 78 /* Compress a packet */ 79 int (*compress)(void *, PACKETPTR *, PACKETPTR, int, int); 80 /* Return compression statistics */ 81 void (*comp_stat)(void *, struct compstat *); 82 83 /* Allocate space for a decompressor (receive side) */ 84 void *(*decomp_alloc)(u_char *, int); 85 /* Free space used by a decompressor */ 86 void (*decomp_free)(void *); 87 /* Initialize a decompressor */ 88 int (*decomp_init)(void *, u_char *, int, int, int, int, int); 89 /* Reset a decompressor */ 90 void (*decomp_reset)(void *); 91 /* Decompress a packet. */ 92 int (*decompress)(void *, PACKETPTR, PACKETPTR *); 93 /* Update state for an incompressible packet received */ 94 void (*incomp)(void *, PACKETPTR); 95 /* Return decompression statistics */ 96 void (*decomp_stat)(void *, struct compstat *); 97 98 LIST_ENTRY(compressor) comp_list; 99 unsigned int comp_refcnt; 100 }; 101 #endif /* PACKETPTR */ 102 103 /* 104 * Return values for decompress routine. 105 * We need to make these distinctions so that we can disable certain 106 * useful functionality, namely sending a CCP reset-request as a result 107 * of an error detected after decompression. This is to avoid infringing 108 * a patent held by Motorola. 109 * Don't you just lurve software patents. 110 */ 111 #define DECOMP_OK 0 /* everything went OK */ 112 #define DECOMP_ERROR 1 /* error detected before decomp. */ 113 #define DECOMP_FATALERROR 2 /* error detected after decomp. */ 114 115 /* 116 * CCP codes. 117 */ 118 #define CCP_CONFREQ 1 119 #define CCP_CONFACK 2 120 #define CCP_CONFNAK 3 121 #define CCP_CONFREJ 4 122 #define CCP_TERMREQ 5 123 #define CCP_TERMACK 6 124 #define CCP_RESETREQ 14 125 #define CCP_RESETACK 15 126 127 /* 128 * Max # bytes for a CCP option 129 */ 130 #define CCP_MAX_OPTION_LENGTH 64 131 132 /* 133 * Parts of a CCP packet. 134 */ 135 #define CCP_CODE(dp) ((dp)[0]) 136 #define CCP_ID(dp) ((dp)[1]) 137 #define CCP_LENGTH(dp) (((dp)[2] << 8) + (dp)[3]) 138 #define CCP_HDRLEN 4 139 140 #define CCP_OPT_CODE(dp) ((dp)[0]) 141 #define CCP_OPT_LENGTH(dp) ((dp)[1]) 142 #define CCP_OPT_MINLEN 2 143 144 /* 145 * Definitions for BSD-Compress. 146 */ 147 #define CI_BSD_COMPRESS 21 /* config. option for BSD-Compress */ 148 #define CILEN_BSD_COMPRESS 3 /* length of config. option */ 149 150 /* Macros for handling the 3rd byte of the BSD-Compress config option. */ 151 #define BSD_NBITS(x) ((x) & 0x1F) /* number of bits requested */ 152 #define BSD_VERSION(x) ((x) >> 5) /* version of option format */ 153 #define BSD_CURRENT_VERSION 1 /* current version number */ 154 #define BSD_MAKE_OPT(v, n) (((v) << 5) | (n)) 155 156 #define BSD_MIN_BITS 9 /* smallest code size supported */ 157 #define BSD_MAX_BITS 15 /* largest code size supported */ 158 159 /* 160 * Definitions for Deflate. 161 */ 162 #define CI_DEFLATE 26 /* config option for Deflate */ 163 #define CI_DEFLATE_DRAFT 24 /* value used in original draft RFC */ 164 165 #define CILEN_DEFLATE 4 /* length of its config option */ 166 167 #define DEFLATE_MIN_SIZE 8 168 #define DEFLATE_MAX_SIZE 15 169 #define DEFLATE_METHOD_VAL 8 170 #define DEFLATE_SIZE(x) (((x) >> 4) + DEFLATE_MIN_SIZE) 171 #define DEFLATE_METHOD(x) ((x) & 0x0F) 172 #define DEFLATE_MAKE_OPT(w) ((((w) - DEFLATE_MIN_SIZE) << 4) \ 173 + DEFLATE_METHOD_VAL) 174 #define DEFLATE_CHK_SEQUENCE 0 175 176 /* 177 * Definitions for MPPE. 178 */ 179 #define CI_MPPE 18 /* config option for MPPE */ 180 #define CILEN_MPPE 6 /* length of config option */ 181 182 #define MPPE_PAD 4 /* MPPE growth per frame */ 183 #define MPPE_MAX_KEY_LEN 16 /* largest key length (128-bit) */ 184 185 /* option bits for ccp_options.mppe */ 186 #define MPPE_OPT_40 0x01 /* 40 bit */ 187 #define MPPE_OPT_128 0x02 /* 128 bit */ 188 #define MPPE_OPT_STATEFUL 0x04 /* stateful mode */ 189 /* unsupported opts */ 190 #define MPPE_OPT_56 0x08 /* 56 bit */ 191 #define MPPE_OPT_MPPC 0x10 /* MPPC compression */ 192 #define MPPE_OPT_D 0x20 /* Unknown */ 193 #define MPPE_OPT_UNSUPPORTED (MPPE_OPT_56|MPPE_OPT_MPPC|MPPE_OPT_D) 194 #define MPPE_OPT_UNKNOWN 0x40 /* Bits !defined in RFC 3078 were set */ 195 196 /* 197 * This is not nice ... the alternative is a bitfield struct though. 198 * And unfortunately, we cannot share the same bits for the option 199 * names above since C and H are the same bit. We could do a uint32_t 200 * but then we have to do a htonl() all the time and/or we still need 201 * to know which octet is which. 202 */ 203 #define MPPE_C_BIT 0x01 /* MPPC */ 204 #define MPPE_D_BIT 0x10 /* Obsolete, usage unknown */ 205 #define MPPE_L_BIT 0x20 /* 40-bit */ 206 #define MPPE_S_BIT 0x40 /* 128-bit */ 207 #define MPPE_M_BIT 0x80 /* 56-bit, not supported */ 208 #define MPPE_H_BIT 0x01 /* Stateless (in a different byte) */ 209 210 /* Does not include H bit; used for least significant octet only. */ 211 #define MPPE_ALL_BITS (MPPE_D_BIT|MPPE_L_BIT|MPPE_S_BIT|MPPE_M_BIT|MPPE_H_BIT) 212 213 /* Build a CI from mppe opts (see RFC 3078) */ 214 #define MPPE_OPTS_TO_CI(opts, ci) \ 215 do { \ 216 u_char *ptr = ci; /* u_char[4] */ \ 217 \ 218 /* H bit */ \ 219 if (opts & MPPE_OPT_STATEFUL) \ 220 *ptr++ = 0x0; \ 221 else \ 222 *ptr++ = MPPE_H_BIT; \ 223 *ptr++ = 0; \ 224 *ptr++ = 0; \ 225 \ 226 /* S,L bits */ \ 227 *ptr = 0; \ 228 if (opts & MPPE_OPT_128) \ 229 *ptr |= MPPE_S_BIT; \ 230 if (opts & MPPE_OPT_40) \ 231 *ptr |= MPPE_L_BIT; \ 232 /* M,D,C bits not supported */ \ 233 } while (/* CONSTCOND */ 0) 234 235 /* The reverse of the above */ 236 #define MPPE_CI_TO_OPTS(ci, opts) \ 237 do { \ 238 u_char *ptr = ci; /* u_char[4] */ \ 239 \ 240 opts = 0; \ 241 \ 242 /* H bit */ \ 243 if (!(ptr[0] & MPPE_H_BIT)) \ 244 opts |= MPPE_OPT_STATEFUL; \ 245 \ 246 /* S,L bits */ \ 247 if (ptr[3] & MPPE_S_BIT) \ 248 opts |= MPPE_OPT_128; \ 249 if (ptr[3] & MPPE_L_BIT) \ 250 opts |= MPPE_OPT_40; \ 251 \ 252 /* M,D,C bits */ \ 253 if (ptr[3] & MPPE_M_BIT) \ 254 opts |= MPPE_OPT_56; \ 255 if (ptr[3] & MPPE_D_BIT) \ 256 opts |= MPPE_OPT_D; \ 257 if (ptr[3] & MPPE_C_BIT) \ 258 opts |= MPPE_OPT_MPPC; \ 259 \ 260 /* Other bits */ \ 261 if (ptr[0] & ~MPPE_H_BIT) \ 262 opts |= MPPE_OPT_UNKNOWN; \ 263 if (ptr[1] || ptr[2]) \ 264 opts |= MPPE_OPT_UNKNOWN; \ 265 if (ptr[3] & ~MPPE_ALL_BITS) \ 266 opts |= MPPE_OPT_UNKNOWN; \ 267 } while (/* CONSTCOND */ 0) 268 269 /* 270 * Definitions for other, as yet unsupported, compression methods. 271 */ 272 #define CI_PREDICTOR_1 1 /* config option for Predictor-1 */ 273 #define CILEN_PREDICTOR_1 2 /* length of its config option */ 274 #define CI_PREDICTOR_2 2 /* config option for Predictor-2 */ 275 #define CILEN_PREDICTOR_2 2 /* length of its config option */ 276 277 #endif /* !_NET_PPP_COMP_H_ */ 278