epan/dissectors/packet-teimanagement.c

   1 /* packet-teimanagement.c
   2  * Routines for LAPD TEI Management frame disassembly
   3  * Rolf Fiedler <rolf.fiedler@innoventif.com>
   4  * based on code by Gilbert Ramirez <gram@alumni.rice.edu>
   5  *
   6  * $Id$
   7  *
   8  * Wireshark - Network traffic analyzer
   9  * By Gerald Combs <gerald@wireshark.org>
  10  * Copyright 1998
  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 #include "config.h"
  28
  29 #include <glib.h>
  30 #include <epan/packet.h>
  31 #include <epan/lapd_sapi.h>
  32
  33 /* ISDN/LAPD references:
  34  *
  35  * http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/isdn.htm
  36  * http://www.ece.wpi.edu/courses/ee535/hwk11cd95/agrebe/agrebe.html
  37  * http://www.acacia-net.com/Clarinet/Protocol/q9213o84.htm
  38  */
  39
  40 static int proto_tei=-1;
  41
  42 static int lm_entity_id=-1;
  43 static int lm_reference=-1;
  44 static int lm_message=-1;
  45 static int lm_action=-1;
  46 static int lm_extend =-1;
  47 static gint lm_subtree=-1;
  48
  49 #define TEI_ID_REQUEST    0x01
  50 #define TEI_ID_ASSIGNED   0x02
  51 #define TEI_ID_DENIED     0x03
  52 #define TEI_ID_CHECK_REQ  0x04
  53 #define TEI_ID_CHECK_RESP 0x05
  54 #define TEI_ID_REMOVE     0x06
  55 #define TEI_ID_VERIFY     0x07
  56
  57 static const value_string tei_msg_vals[]={
  58     { TEI_ID_REQUEST,    "Identity Request"},
  59     { TEI_ID_ASSIGNED,   "Identity Assigned"},
  60     { TEI_ID_DENIED,     "Identity Denied"},
  61     { TEI_ID_CHECK_REQ,  "Identity Check Request"},
  62     { TEI_ID_CHECK_RESP, "Identity Check Response"},
  63     { TEI_ID_REMOVE,     "Identity Remove"},
  64     { TEI_ID_VERIFY,     "Identity Verify"},
  65     { 0, NULL}
  66 };
  67
  68 static void
  69 dissect_teimanagement(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  70 {
  71     proto_tree *tei_tree = NULL;
  72     proto_item *tei_ti;
  73     guint8 message;
  74
  75     col_set_str(pinfo->cinfo, COL_PROTOCOL, "TEI");
  76     col_clear(pinfo->cinfo, COL_INFO);
  77
  78     if (tree) {
  79         tei_ti = proto_tree_add_item(tree, proto_tei, tvb, 0, 5, ENC_NA);
  80         tei_tree = proto_item_add_subtree(tei_ti, lm_subtree);
  81
  82         proto_tree_add_item(tei_tree, lm_entity_id, tvb, 0, 1, ENC_BIG_ENDIAN);
  83         proto_tree_add_item(tei_tree, lm_reference,  tvb, 1, 2, ENC_BIG_ENDIAN);
  84     }
  85
  86     message = tvb_get_guint8(tvb, 3);
  87         col_add_str(pinfo->cinfo, COL_INFO,
  88             val_to_str(message, tei_msg_vals, "Unknown message type (0x%04x)"));
  89     if (tree) {
  90         proto_tree_add_uint(tei_tree, lm_message, tvb, 3, 1, message);
  91         proto_tree_add_item(tei_tree, lm_action, tvb, 4, 1, ENC_BIG_ENDIAN);
  92         proto_tree_add_item(tei_tree, lm_extend, tvb, 4, 1, ENC_BIG_ENDIAN);
  93     }
  94 }
  95
  96 void
  97 proto_register_teimanagement(void)
  98 {
  99     static gint *subtree[]={
 100         &lm_subtree
 101     };
 102
 103     static hf_register_info hf[] = {
 104         { &lm_entity_id,
 105           { "Entity", "tei.entity", FT_UINT8, BASE_HEX, NULL, 0x0,
 106                 "Layer Management Entity Identifier", HFILL }},
 107
 108         { &lm_reference,
 109           { "Reference", "tei.reference", FT_UINT16, BASE_DEC, NULL, 0x0,
 110                 "Reference Number", HFILL }},
 111
 112         { &lm_message,
 113           { "Msg", "tei.msg", FT_UINT8, BASE_DEC, VALS(tei_msg_vals), 0x0,
 114                 "Message Type", HFILL }},
 115
 116         { &lm_action,
 117           { "Action", "tei.action", FT_UINT8, BASE_DEC, NULL, 0xfe,
 118                 "Action Indicator", HFILL }},
 119
 120         { &lm_extend,
 121           { "Extend", "tei.extend", FT_UINT8, BASE_DEC, NULL, 0x01,
 122                 "Extension Indicator", HFILL }}
 123     };
 124
 125     proto_tei = proto_register_protocol("TEI Management Procedure, Channel D (LAPD)",
 126                                          "TEI_MANAGEMENT", "tei_management");
 127     proto_register_field_array (proto_tei, hf, array_length(hf));
 128     proto_register_subtree_array(subtree, array_length(subtree));
 129 }
 130
 131 void
 132 proto_reg_handoff_teimanagement(void)
 133 {
 134     dissector_handle_t teimanagement_handle;
 135
 136     teimanagement_handle = create_dissector_handle(dissect_teimanagement,
 137         proto_tei);
 138     dissector_add_uint("lapd.sapi", LAPD_SAPI_L2, teimanagement_handle);
 139 }