sys/netproto/atalk/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  * $DragonFly: src/sys/netproto/atalk/ddp.h,v 1.2 2006/10/23 21:50:33 dillon Exp $
  24  */
  25 #ifndef _NETATALK_DDP_H_
  26 #define _NETATALK_DDP_H_
  27
  28 /*
  29  * <-1byte(8bits) ->
  30  * +---------------+
  31  * | 0 | hopc  |len|
  32  * +---------------+
  33  * | len (cont)    |
  34  * +---------------+
  35  * |               |
  36  * +- DDP csum    -+
  37  * |               |
  38  * +---------------+
  39  * |               |
  40  * +- Dest NET    -+
  41  * |               |
  42  * +---------------+
  43  * |               |
  44  * +- Src NET     -+
  45  * |               |
  46  * +---------------+
  47  * | Dest NODE     |
  48  * +---------------+
  49  * | Src NODE      |
  50  * +---------------+
  51  * | Dest PORT     |
  52  * +---------------+
  53  * | Src PORT      |
  54  * +---------------+
  55  *
  56  * On Apples, there is also a ddp_type field, after src_port. However,
  57  * under this unix implementation, user level processes need to be able
  58  * to set the ddp_type. In later revisions, the ddp_type may only be
  59  * available in a raw_appletalk interface.
  60  */
  61
  62 struct elaphdr {
  63     u_char      el_dnode;
  64     u_char      el_snode;
  65     u_char      el_type;
  66 };
  67
  68 #define SZ_ELAPHDR      3
  69
  70 #define ELAP_DDPSHORT   0x01
  71 #define ELAP_DDPEXTEND  0x02
  72
  73 /*
  74  * Extended DDP header. Includes sickness for dealing with arbitrary
  75  * bitfields on a little-endian arch.
  76  */
  77 struct ddpehdr {
  78     union {
  79         struct {
  80 #if BYTE_ORDER == BIG_ENDIAN
  81     unsigned            dub_pad:2;
  82     unsigned            dub_hops:4;
  83     unsigned            dub_len:10;
  84     unsigned            dub_sum:16;
  85 #endif
  86 #if BYTE_ORDER == LITTLE_ENDIAN
  87     unsigned            dub_sum:16;
  88     unsigned            dub_len:10;
  89     unsigned            dub_hops:4;
  90     unsigned            dub_pad:2;
  91 #endif
  92         } du_bits;
  93         unsigned        du_bytes;
  94     } deh_u;
  95 #define deh_pad         deh_u.du_bits.dub_pad
  96 #define deh_hops        deh_u.du_bits.dub_hops
  97 #define deh_len         deh_u.du_bits.dub_len
  98 #define deh_sum         deh_u.du_bits.dub_sum
  99 #define deh_bytes       deh_u.du_bytes
 100     u_short             deh_dnet;
 101     u_short             deh_snet;
 102     u_char              deh_dnode;
 103     u_char              deh_snode;
 104     u_char              deh_dport;
 105     u_char              deh_sport;
 106 };
 107
 108 #define DDP_MAXHOPS     15
 109
 110 struct ddpshdr {
 111     union {
 112         struct {
 113 #if BYTE_ORDER == BIG_ENDIAN
 114     unsigned            dub_pad:6;
 115     unsigned            dub_len:10;
 116     unsigned            dub_dport:8;
 117     unsigned            dub_sport:8;
 118 #endif
 119 #if BYTE_ORDER == LITTLE_ENDIAN
 120     unsigned            dub_sport:8;
 121     unsigned            dub_dport:8;
 122     unsigned            dub_len:10;
 123     unsigned            dub_pad:6;
 124 #endif
 125         } du_bits;
 126         unsigned        du_bytes;
 127     } dsh_u;
 128 #define dsh_pad         dsh_u.du_bits.dub_pad
 129 #define dsh_len         dsh_u.du_bits.dub_len
 130 #define dsh_dport       dsh_u.du_bits.dub_dport
 131 #define dsh_sport       dsh_u.du_bits.dub_sport
 132 #define dsh_bytes       dsh_u.du_bytes
 133 };
 134
 135 #endif /* _NETATALK_DDP_H_ */