sys/netatalk/ddp.h

   1 /*-
   2  * Copyright (c) 1990, 1991 Regents of The University of Michigan.
   3  * All Rights Reserved.
   4  *
   5  * Permission to use, copy, modify, and distribute this software and
   6  * its documentation for any purpose and without fee is hereby granted,
   7  * provided that the above copyright notice appears in all copies and
   8  * that both that copyright notice and this permission notice appear
   9  * in supporting documentation, and that the name of The University
  10  * of Michigan not be used in advertising or publicity pertaining to
  11  * distribution of the software without specific, written prior
  12  * permission. This software is supplied as is without expressed or
  13  * implied warranties of any kind.
  14  *
  15  *      Research Systems Unix Group
  16  *      The University of Michigan
  17  *      c/o Mike Clark
  18  *      535 W. William Street
  19  *      Ann Arbor, Michigan
  20  *      +1-313-763-0525
  21  *      netatalk@itd.umich.edu
  22  *
  23  * $FreeBSD$
  24  */
  25
  26 #ifndef _NETATALK_DDP_H_
  27 #define _NETATALK_DDP_H_
  28
  29 /*-
  30  * <-1byte(8bits) ->
  31  * +---------------+
  32  * | 0 | hopc  |len|
  33  * +---------------+
  34  * | len (cont)    |
  35  * +---------------+
  36  * |               |
  37  * +- DDP csum    -+
  38  * |               |
  39  * +---------------+
  40  * |               |
  41  * +- Dest NET    -+
  42  * |               |
  43  * +---------------+
  44  * |               |
  45  * +- Src NET     -+
  46  * |               |
  47  * +---------------+
  48  * | Dest NODE     |
  49  * +---------------+
  50  * | Src NODE      |
  51  * +---------------+
  52  * | Dest PORT     |
  53  * +---------------+
  54  * | Src PORT      |
  55  * +---------------+
  56  *
  57  * On Apples, there is also a ddp_type field, after src_port.  However, under
  58  * this unix implementation, user level processes need to be able to set the
  59  * ddp_type.  In later revisions, the ddp_type may only be available in a
  60  * raw_appletalk interface.
  61  */
  62
  63 struct elaphdr {
  64         u_char  el_dnode;
  65         u_char  el_snode;
  66         u_char  el_type;
  67 } __packed;
  68
  69 #define SZ_ELAPHDR      3
  70
  71 #define ELAP_DDPSHORT   0x01
  72 #define ELAP_DDPEXTEND  0x02
  73
  74 /*
  75  * Extended DDP header. Includes sickness for dealing with arbitrary
  76  * bitfields on a little-endian arch.
  77  */
  78 struct ddpehdr {
  79         union {
  80                 struct {
  81 #if BYTE_ORDER == BIG_ENDIAN
  82                         unsigned        dub_pad:2;
  83                         unsigned        dub_hops:4;
  84                         unsigned        dub_len:10;
  85                         unsigned        dub_sum:16;
  86 #endif
  87 #if BYTE_ORDER == LITTLE_ENDIAN
  88                         unsigned        dub_sum:16;
  89                         unsigned        dub_len:10;
  90                         unsigned        dub_hops:4;
  91                         unsigned        dub_pad:2;
  92 #endif
  93                 } __packed du_bits;
  94                 unsigned        du_bytes;
  95         } deh_u;
  96         u_short deh_dnet;
  97         u_short deh_snet;
  98         u_char  deh_dnode;
  99         u_char  deh_snode;
 100         u_char  deh_dport;
 101         u_char  deh_sport;
 102 } __packed;
 103 #define deh_pad         deh_u.du_bits.dub_pad
 104 #define deh_hops        deh_u.du_bits.dub_hops
 105 #define deh_len         deh_u.du_bits.dub_len
 106 #define deh_sum         deh_u.du_bits.dub_sum
 107 #define deh_bytes       deh_u.du_bytes
 108
 109 #define DDP_MAXHOPS     15
 110
 111 struct ddpshdr {
 112         union {
 113                 struct {
 114 #if BYTE_ORDER == BIG_ENDIAN
 115                         unsigned        dub_pad:6;
 116                         unsigned        dub_len:10;
 117                         unsigned        dub_dport:8;
 118                         unsigned        dub_sport:8;
 119 #endif
 120 #if BYTE_ORDER == LITTLE_ENDIAN
 121                         unsigned        dub_sport:8;
 122                         unsigned        dub_dport:8;
 123                         unsigned        dub_len:10;
 124                         unsigned        dub_pad:6;
 125 #endif
 126                 } __packed du_bits;
 127                 unsigned        du_bytes;
 128         } dsh_u;
 129 } __packed;
 130
 131 #define dsh_pad         dsh_u.du_bits.dub_pad
 132 #define dsh_len         dsh_u.du_bits.dub_len
 133 #define dsh_dport       dsh_u.du_bits.dub_dport
 134 #define dsh_sport       dsh_u.du_bits.dub_sport
 135 #define dsh_bytes       dsh_u.du_bytes
 136
 137 #endif /* _NETATALK_DDP_H_ */