sys/netatalk/ddp.h

   1 /*
   2  * $Id: ddp.h,v 1.2 2001-06-29 14:14:47 rufustfirefly Exp $
   3  *
   4  * Copyright (c) 1990,1991 Regents of The University of Michigan.
   5  * All Rights Reserved. See COPYRIGHT.
   6  *
   7  */
   8
   9 /*
  10  * <-1byte(8bits) ->
  11  * +---------------+
  12  * | 0 | hopc  |len|
  13  * +---------------+
  14  * | len (cont)    |
  15  * +---------------+
  16  * |               |
  17  * +- DDP csum    -+
  18  * |               |
  19  * +---------------+
  20  * |               |
  21  * +- Dest NET    -+
  22  * |               |
  23  * +---------------+
  24  * |               |
  25  * +- Src NET     -+
  26  * |               |
  27  * +---------------+
  28  * | Dest NODE     |
  29  * +---------------+
  30  * | Src NODE      |
  31  * +---------------+
  32  * | Dest PORT     |
  33  * +---------------+
  34  * | Src PORT      |
  35  * +---------------+
  36  *
  37  * On Apples, there is also a ddp_type field, after src_port. However,
  38  * under this unix implementation, user level processes need to be able
  39  * to set the ddp_type. In later revisions, the ddp_type may only be
  40  * available in a raw_appletalk interface.
  41  */
  42
  43 #ifndef _NETATALK_DDP_H
  44 #define _NETATALK_DDP_H 1
  45
  46 #include <netatalk/endian.h>
  47
  48 struct elaphdr {
  49     u_char      el_dnode;
  50     u_char      el_snode;
  51     u_char      el_type;
  52 };
  53
  54 #define SZ_ELAPHDR      3
  55
  56 #define ELAP_DDPSHORT   0x01
  57 #define ELAP_DDPEXTEND  0x02
  58
  59 /*
  60  * Extended DDP header. Includes sickness for dealing with arbitrary
  61  * bitfields on a little-endian arch.
  62  */
  63 struct ddpehdr {
  64     union {
  65         struct {
  66 #if BYTE_ORDER == BIG_ENDIAN
  67     unsigned            dub_pad:2;
  68     unsigned            dub_hops:4;
  69     unsigned            dub_len:10;
  70     unsigned            dub_sum:16;
  71 #else /* BYTE_ORDER == BIG_ENDIAN */
  72 #if BYTE_ORDER == LITTLE_ENDIAN
  73     unsigned            dub_sum:16;
  74     unsigned            dub_len:10;
  75     unsigned            dub_hops:4;
  76     unsigned            dub_pad:2;
  77 #else /* BYTE_ORDER == LITTLE_ENDIAN */
  78     OOPS!
  79 #endif /* BYTE_ORDER == LITTLE_ENDIAN */
  80 #endif /* BYTE_ORDER == BIG_ENDIAN */
  81         } du_bits;
  82         unsigned        du_bytes;
  83     } deh_u;
  84 #define deh_pad         deh_u.du_bits.dub_pad
  85 #define deh_hops        deh_u.du_bits.dub_hops
  86 #define deh_len         deh_u.du_bits.dub_len
  87 #define deh_sum         deh_u.du_bits.dub_sum
  88 #define deh_bytes       deh_u.du_bytes
  89     u_short             deh_dnet;
  90     u_short             deh_snet;
  91     u_char              deh_dnode;
  92     u_char              deh_snode;
  93     u_char              deh_dport;
  94     u_char              deh_sport;
  95 };
  96
  97 #define SZ_DDPEHDR      12
  98
  99 #define DDP_MAXHOPS     15
 100
 101 struct ddpshdr {
 102     union {
 103         struct {
 104 #if BYTE_ORDER == BIG_ENDIAN
 105     unsigned            dub_pad:6;
 106     unsigned            dub_len:10;
 107     unsigned            dub_dport:8;
 108     unsigned            dub_sport:8;
 109 #endif /* BYTE_ORDER == BIG_ENDIAN */
 110 #if BYTE_ORDER == LITTLE_ENDIAN
 111     unsigned            dub_sport:8;
 112     unsigned            dub_dport:8;
 113     unsigned            dub_len:10;
 114     unsigned            dub_pad:6;
 115 #endif /* BYTE_ORDER == LITTLE_ENDIAN */
 116         } du_bits;
 117         unsigned        du_bytes;
 118     } dsh_u;
 119 #define dsh_pad         dsh_u.du_bits.dub_pad
 120 #define dsh_len         dsh_u.du_bits.dub_len
 121 #define dsh_dport       dsh_u.du_bits.dub_dport
 122 #define dsh_sport       dsh_u.du_bits.dub_sport
 123 #define dsh_bytes       dsh_u.du_bytes
 124 };
 125 #define SZ_DDPSHDR      4
 126
 127 #endif /* netatalk/ddp.h */