epan/dissectors/packet-esis.h

   1 /* packet-esis.h
   2  * Defines and such for ESIS protocol decode.
   3  *
   4  * $Id$
   5  * Ralf Schneider <Ralf.Schneider@t-online.de>
   6  *
   7  * Wireshark - Network traffic analyzer
   8  * By Gerald Combs <gerald@wireshark.org>
   9  * Copyright 1998 Gerald Combs
  10  *
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  25  *
  26  *
  27  */
  28
  29 #ifndef _PACKET_ESIS_H
  30 #define _PACKET_ESIS_H
  31
  32 /* The version we support is 1 */
  33 #define ESIS_REQUIRED_VERSION    1
  34
  35 /* ESIS PDU types */
  36 #define ESIS_ESH_PDU    02
  37 #define ESIS_ISH_PDU    04
  38 #define ESIS_RD_PDU     06
  39
  40 /* The length of the fixed part */
  41 #define ESIS_HDR_FIXED_LENGTH 9
  42
  43 /* Inline Defines for masking */
  44 #define esis_type esis_type_reserved&OSI_PDU_TYPE_MASK
  45 #define esis_r8   esis_type_reserved&BIT_8
  46 #define esis_r7   esis_type_reserved&BIT_7
  47 #define esis_r6   esis_type_reserved&BIT_6
  48
  49 /* The fixed part (9 octets) of the ESIS protocol header */
  50 typedef struct {
  51   guint8 esis_nlpi;           /* Network Layer Protocol Identifier == 0x82   */
  52   guint8 esis_length;         /* Header ( PDU too, NoData ) length in octets */
  53   guint8 esis_version;        /* ISIS version, must be 0x01 */
  54   guint8 esis_reserved;       /* reserved byte, must be 0   */
  55   guint8 esis_type_reserved;  /* packet type & MS-Bits (8-6) reserved */
  56   guint8 esis_holdtime[2];    /* Maximum time (sec) this PDU is valid */
  57   guint8 esis_checksum[2];    /* Computed on whole PDU Header, 0 means ignore */
  58 } esis_hdr_t;
  59
  60 #endif /* _PACKET_ESIS_H */