include/net/ppp-comp.h

   1 /*
   2  * ppp-comp.h - Definitions for doing PPP packet compression.
   3  *
   4  * Copyright 2000 Sun Microsystems, Inc.  All rights reserved.
   5  * Use is subject to license terms.
   6  *
   7  * Copyright (c) 1994 The Australian National University.
   8  * All rights reserved.
   9  *
  10  * Permission to use, copy, modify, and distribute this software and its
  11  * documentation is hereby granted, provided that the above copyright
  12  * notice appears in all copies.  This software is provided without any
  13  * warranty, express or implied. The Australian National University
  14  * makes no representations about the suitability of this software for
  15  * any purpose.
  16  *
  17  * IN NO EVENT SHALL THE AUSTRALIAN NATIONAL UNIVERSITY BE LIABLE TO ANY
  18  * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  19  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
  20  * THE AUSTRALIAN NATIONAL UNIVERSITY HAVE BEEN ADVISED OF THE POSSIBILITY
  21  * OF SUCH DAMAGE.
  22  *
  23  * THE AUSTRALIAN NATIONAL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES,
  24  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
  25  * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  26  * ON AN "AS IS" BASIS, AND THE AUSTRALIAN NATIONAL UNIVERSITY HAS NO
  27  * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,
  28  * OR MODIFICATIONS.
  29  *
  30  * $Id: ppp-comp.h,v 1.11 1998/03/25 03:33:34 paulus Exp $
  31  */
  32
  33 #ifndef _NET_PPP_COMP_H
  34 #define _NET_PPP_COMP_H
  35
  36 #pragma ident   "%Z%%M% %I%     %E% SMI"
  37
  38 #ifdef __cplusplus
  39 extern "C" {
  40 #endif
  41
  42 /*
  43  * The following symbols control whether we include code for
  44  * various compression methods.
  45  */
  46 #ifndef DO_BSD_COMPRESS
  47 #define DO_BSD_COMPRESS 1       /* by default, include BSD-Compress */
  48 #endif
  49 #ifndef DO_DEFLATE
  50 #define DO_DEFLATE      1       /* by default, include Deflate */
  51 #endif
  52 #define DO_PREDICTOR_1  0
  53 #define DO_PREDICTOR_2  0
  54
  55 /*
  56  * Structure giving methods for compression/decompression.
  57  */
  58 #ifdef PACKETPTR
  59 struct compressor {
  60         int     compress_proto; /* CCP compression protocol number */
  61
  62         /* Allocate space for a compressor (transmit side) */
  63         void    *(*comp_alloc) __P((uchar_t *options, int opt_len));
  64         /* Free space used by a compressor */
  65         void    (*comp_free) __P((void *state));
  66         /* Initialize a compressor */
  67         int     (*comp_init) __P((void *state, uchar_t *options, int opt_len,
  68             int unit, int hdrlen, int debug));
  69         /* Reset a compressor */
  70         void    (*comp_reset) __P((void *state));
  71         /* Compress a packet */
  72         int     (*compress) __P((void *state, PACKETPTR *mret,
  73             PACKETPTR mp, int orig_len, int max_len));
  74         /* Return compression statistics */
  75         void    (*comp_stat) __P((void *state, struct compstat *stats));
  76
  77         /* Allocate space for a decompressor (receive side) */
  78         void    *(*decomp_alloc) __P((uchar_t *options, int opt_len));
  79         /* Free space used by a decompressor */
  80         void    (*decomp_free) __P((void *state));
  81         /* Initialize a decompressor */
  82         int     (*decomp_init) __P((void *state, uchar_t *options, int opt_len,
  83                                     int unit, int hdrlen, int mru, int debug));
  84         /* Reset a decompressor */
  85         void    (*decomp_reset) __P((void *state));
  86         /* Decompress a packet. */
  87         int     (*decompress) __P((void *state, PACKETPTR *mp));
  88         /* Update state for an incompressible packet received */
  89         int     (*incomp) __P((void *state, PACKETPTR mp));
  90         /* Return decompression statistics */
  91         void    (*decomp_stat) __P((void *state, struct compstat *stats));
  92
  93         /* Set or change compression effort level */
  94         int     (*set_effort) __P((void *xstate, void *rstate,
  95             int effortlevel));
  96 };
  97 #endif /* PACKETPTR */
  98
  99 /*
 100  * Return values for decompress routine.
 101  * We need to make these distinctions so that we can disable certain
 102  * useful functionality, namely sending a CCP reset-request as a result
 103  * of an error detected after decompression.  This is to avoid infringing
 104  * a patent held by Motorola.
 105  * Don't you just lurve software patents.
 106  */
 107 #define DECOMP_OK               0       /* everything went OK */
 108 #define DECOMP_ERROR            1       /* error detected before decomp. */
 109 #define DECOMP_FATALERROR       2       /* error detected after decomp. */
 110
 111 /*
 112  * CCP codes.
 113  */
 114 #define CCP_CONFREQ     1
 115 #define CCP_CONFACK     2
 116 #define CCP_TERMREQ     5
 117 #define CCP_TERMACK     6
 118 #define CCP_RESETREQ    14
 119 #define CCP_RESETACK    15
 120
 121 /*
 122  * Max # bytes for a CCP option
 123  */
 124 #define CCP_MAX_OPTION_LENGTH   32
 125
 126 /*
 127  * Parts of a CCP packet.
 128  */
 129 #define CCP_CODE(dp)            ((dp)[0])
 130 #define CCP_ID(dp)              ((dp)[1])
 131 #define CCP_LENGTH(dp)          (((dp)[2] << 8) + (dp)[3])
 132 #define CCP_HDRLEN              4
 133
 134 #define CCP_OPT_CODE(dp)        ((dp)[0])
 135 #define CCP_OPT_LENGTH(dp)      ((dp)[1])
 136 #define CCP_OPT_MINLEN          2
 137
 138 /*
 139  * Definitions for BSD-Compress.
 140  */
 141 #define CI_BSD_COMPRESS         21      /* config. option for BSD-Compress */
 142 #define CILEN_BSD_COMPRESS      3       /* length of config. option */
 143
 144 /* Macros for handling the 3rd byte of the BSD-Compress config option. */
 145 #define BSD_NBITS(x)            ((x) & 0x1F)    /* number of bits requested */
 146 #define BSD_VERSION(x)          ((x) >> 5)      /* version of option format */
 147 #define BSD_CURRENT_VERSION     1               /* current version number */
 148 #define BSD_MAKE_OPT(v, n)      (((v) << 5) | (n))
 149
 150 #define BSD_MIN_BITS            9       /* smallest code size supported */
 151 #define BSD_MAX_BITS            15      /* largest code size supported */
 152
 153 /*
 154  * Definitions for Deflate.
 155  */
 156 #define CI_DEFLATE              26      /* config option for Deflate */
 157 #define CI_DEFLATE_DRAFT        24      /* value used in original draft RFC */
 158 #define CILEN_DEFLATE           4       /* length of its config option */
 159
 160 #define DEFLATE_MIN_SIZE        8
 161 #define DEFLATE_MAX_SIZE        15
 162 #define DEFLATE_METHOD_VAL      8
 163 #define DEFLATE_SIZE(x)         (((x) >> 4) + DEFLATE_MIN_SIZE)
 164 #define DEFLATE_METHOD(x)       ((x) & 0x0F)
 165 #define DEFLATE_MAKE_OPT(w)     ((((w) - DEFLATE_MIN_SIZE) << 4) \
 166                                     + DEFLATE_METHOD_VAL)
 167 #define DEFLATE_CHK_SEQUENCE    0
 168
 169 /*
 170  * Definitions for other, as yet unsupported, compression methods.
 171  */
 172 #define CI_PREDICTOR_1          1       /* config option for Predictor-1 */
 173 #define CILEN_PREDICTOR_1       2       /* length of its config option */
 174 #define CI_PREDICTOR_2          2       /* config option for Predictor-2 */
 175 #define CILEN_PREDICTOR_2       2       /* length of its config option */
 176
 177 /*
 178  * Note that some systems emit requests for STAC using a length of 6.
 179  * The extra octet is 00 and should be ignored.
 180  */
 181 #define CI_STAC                 17      /* config option for STAC LZS */
 182 #define CILEN_STAC              5       /* length of its config option */
 183
 184 #define STAC_CHK_NONE           0       /* No checking */
 185 #define STAC_CHK_LCB            1       /* Longitudinal Check Bytes */
 186 #define STAC_CHK_CRC            2       /* Cyclic Redundancy Check */
 187 #define STAC_CHK_SEQ            3       /* Sequence Number */
 188 #define STAC_CHK_EXTENDED       4       /* Extended (Microsoft) */
 189
 190 #define CI_MPPC                 18      /* config option for MS-PPC */
 191 #define CILEN_MPPC              6       /* length of its config option */
 192
 193 #define MPPC_COMP               0x00000001      /* Compression */
 194 #define MPPC_40LANM             0x00000010      /* MPPE, 40 bit LANManager */
 195 #define MPPC_40NT               0x00000020      /* MPPE, 40 bit NT key */
 196 #define MPPC_128NT              0x00000040      /* MPPE, 128 bit NT key */
 197 #define MPPC_56NT               0x00000080      /* MPPE, 56 bit NT key */
 198 #define MPPC_PBP                0x01000000      /* Packet-by-Packet mode */
 199 #define MPPC_MPPE               0x000000F0
 200
 201 #ifdef __cplusplus
 202 }
 203 #endif
 204
 205 #endif /* _NET_PPP_COMP_H */