include/uapi/linux/ppp-comp.h

   1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
   2 /*
   3  * ppp-comp.h - Definitions for doing PPP packet compression.
   4  *
   5  * Copyright 1994-1998 Paul Mackerras.
   6  *
   7  *  This program is free software; you can redistribute it and/or
   8  *  modify it under the terms of the GNU General Public License
   9  *  version 2 as published by the Free Software Foundation.
  10  */
  11 #ifndef _UAPI_NET_PPP_COMP_H
  12 #define _UAPI_NET_PPP_COMP_H
  13
  14
  15 /*
  16  * CCP codes.
  17  */
  18
  19 #define CCP_CONFREQ     1
  20 #define CCP_CONFACK     2
  21 #define CCP_TERMREQ     5
  22 #define CCP_TERMACK     6
  23 #define CCP_RESETREQ    14
  24 #define CCP_RESETACK    15
  25
  26 /*
  27  * Max # bytes for a CCP option
  28  */
  29
  30 #define CCP_MAX_OPTION_LENGTH   32
  31
  32 /*
  33  * Parts of a CCP packet.
  34  */
  35
  36 #define CCP_CODE(dp)            ((dp)[0])
  37 #define CCP_ID(dp)              ((dp)[1])
  38 #define CCP_LENGTH(dp)          (((dp)[2] << 8) + (dp)[3])
  39 #define CCP_HDRLEN              4
  40
  41 #define CCP_OPT_CODE(dp)        ((dp)[0])
  42 #define CCP_OPT_LENGTH(dp)      ((dp)[1])
  43 #define CCP_OPT_MINLEN          2
  44
  45 /*
  46  * Definitions for BSD-Compress.
  47  */
  48
  49 #define CI_BSD_COMPRESS         21      /* config. option for BSD-Compress */
  50 #define CILEN_BSD_COMPRESS      3       /* length of config. option */
  51
  52 /* Macros for handling the 3rd byte of the BSD-Compress config option. */
  53 #define BSD_NBITS(x)            ((x) & 0x1F)    /* number of bits requested */
  54 #define BSD_VERSION(x)          ((x) >> 5)      /* version of option format */
  55 #define BSD_CURRENT_VERSION     1               /* current version number */
  56 #define BSD_MAKE_OPT(v, n)      (((v) << 5) | (n))
  57
  58 #define BSD_MIN_BITS            9       /* smallest code size supported */
  59 #define BSD_MAX_BITS            15      /* largest code size supported */
  60
  61 /*
  62  * Definitions for Deflate.
  63  */
  64
  65 #define CI_DEFLATE              26      /* config option for Deflate */
  66 #define CI_DEFLATE_DRAFT        24      /* value used in original draft RFC */
  67 #define CILEN_DEFLATE           4       /* length of its config option */
  68
  69 #define DEFLATE_MIN_SIZE        9
  70 #define DEFLATE_MAX_SIZE        15
  71 #define DEFLATE_METHOD_VAL      8
  72 #define DEFLATE_SIZE(x)         (((x) >> 4) + 8)
  73 #define DEFLATE_METHOD(x)       ((x) & 0x0F)
  74 #define DEFLATE_MAKE_OPT(w)     ((((w) - 8) << 4) + DEFLATE_METHOD_VAL)
  75 #define DEFLATE_CHK_SEQUENCE    0
  76
  77 /*
  78  * Definitions for MPPE.
  79  */
  80
  81 #define CI_MPPE                18      /* config option for MPPE */
  82 #define CILEN_MPPE              6      /* length of config option */
  83
  84 /*
  85  * Definitions for other, as yet unsupported, compression methods.
  86  */
  87
  88 #define CI_PREDICTOR_1          1       /* config option for Predictor-1 */
  89 #define CILEN_PREDICTOR_1       2       /* length of its config option */
  90 #define CI_PREDICTOR_2          2       /* config option for Predictor-2 */
  91 #define CILEN_PREDICTOR_2       2       /* length of its config option */
  92
  93
  94 #endif /* _UAPI_NET_PPP_COMP_H */