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: packet-teimanagement.c,v 1.1 2004/01/26 20:48:38 guy Exp $
   7  *
   8  * Ethereal - Network traffic analyzer
   9  * By Gerald Combs <gerald@ethereal.com>
  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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  25  */
  26
  27 #ifdef HAVE_CONFIG_H
  28 # include "config.h"
  29 #endif
  30
  31 #include <stdio.h>
  32 #include <glib.h>
  33 #include <string.h>
  34 #include <epan/packet.h>
  35 #include "lapd_sapi.h"
  36
  37 /* ISDN/LAPD references:
  38  *
  39  * http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/isdn.htm
  40  * http://www.ece.wpi.edu/courses/ee535/hwk11cd95/agrebe/agrebe.html
  41  * http://www.acacia-net.com/Clarinet/Protocol/q9213o84.htm
  42  */
  43
  44 static int proto_tei=-1;
  45
  46 static int lm_entity_id=-1;
  47 static int lm_reference=-1;
  48 static int lm_message=-1;
  49 static int lm_action=-1;
  50 static int lm_extend =-1;
  51 static gint lm_subtree=-1;
  52
  53 #define TEI_ID_REQUEST    0x01
  54 #define TEI_ID_ASSIGNED   0x02
  55 #define TEI_ID_DENIED     0x03
  56 #define TEI_ID_CHECK_REQ  0x04
  57 #define TEI_ID_CHECK_RESP 0x05
  58 #define TEI_ID_REMOVE     0x06
  59 #define TEI_ID_VERIFY     0x07
  60
  61 static const value_string tei_msg_vals[]={
  62     { TEI_ID_REQUEST,    "Identity Request"},
  63     { TEI_ID_ASSIGNED,   "Identity Assigned"},
  64     { TEI_ID_DENIED,     "Identity Denied"},
  65     { TEI_ID_CHECK_REQ,  "Identity Check Request"},
  66     { TEI_ID_CHECK_RESP, "Identity Check Response"},
  67     { TEI_ID_REMOVE,     "Identity Remove"},
  68     { TEI_ID_VERIFY,     "Identity Verify"},
  69     { 0, NULL}
  70 };
  71
  72 static void
  73 dissect_teimanagement(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  74 {
  75     proto_tree *tei_tree = NULL;
  76     proto_item *tei_ti;
  77     guint8 message;
  78
  79     if(check_col(pinfo->cinfo, COL_PROTOCOL))
  80         col_set_str(pinfo->cinfo, COL_PROTOCOL, "TEI");
  81     if (check_col(pinfo->cinfo, COL_INFO))
  82         col_clear(pinfo->cinfo, COL_INFO);
  83
  84     if (tree) {
  85         tei_ti = proto_tree_add_item(tree, proto_tei, tvb, 0, 5, FALSE);
  86         tei_tree = proto_item_add_subtree(tei_ti, lm_subtree);
  87
  88         proto_tree_add_item(tei_tree, lm_entity_id, tvb, 0, 1, FALSE);
  89         proto_tree_add_item(tei_tree, lm_reference,  tvb, 1, 2, FALSE);
  90     }
  91
  92     message = tvb_get_guint8(tvb, 3);
  93     if (check_col(pinfo->cinfo, COL_INFO))
  94         col_set_str(pinfo->cinfo, COL_INFO,
  95             val_to_str(message, tei_msg_vals, "Unknown message type (0x%04x)"));
  96     if (tree) {
  97         proto_tree_add_uint(tei_tree, lm_message, tvb, 3, 1, message);
  98         proto_tree_add_item(tei_tree, lm_action, tvb, 4, 1, FALSE);
  99         proto_tree_add_item(tei_tree, lm_extend, tvb, 4, 1, FALSE);
 100     }
 101 }
 102
 103 void
 104 proto_register_teimanagement(void)
 105 {
 106     static gint *subtree[]={
 107         &lm_subtree
 108     };
 109
 110     static hf_register_info hf[] = {
 111         { &lm_entity_id,
 112           { "Entity", "tei.entity", FT_UINT8, BASE_HEX, NULL, 0x0,
 113                 "Layer Management Entity Identifier", HFILL }},
 114
 115         { &lm_reference,
 116           { "Reference", "tei.reference", FT_UINT16, BASE_DEC, NULL, 0x0,
 117                 "Reference Number", HFILL }},
 118
 119         { &lm_message,
 120           { "Msg", "tei.msg", FT_UINT8, BASE_DEC, VALS(tei_msg_vals), 0x0,
 121                 "Message Type", HFILL }},
 122
 123         { &lm_action,
 124           { "Action", "tei.action", FT_UINT8, BASE_DEC, NULL, 0xfe,
 125                 "Action Indicator", HFILL }},
 126
 127         { &lm_extend,
 128           { "Extend", "tei.extend", FT_UINT8, BASE_DEC, NULL, 0x01,
 129                 "Extension Indicator", HFILL }}
 130     };
 131
 132     proto_tei = proto_register_protocol("TEI Management Procedure, Channel D (LAPD)",
 133                                          "TEI_MANAGEMENT", "tei_management");
 134     proto_register_field_array (proto_tei, hf, array_length(hf));
 135     proto_register_subtree_array(subtree, array_length(subtree));
 136 }
 137
 138 void
 139 proto_reg_handoff_teimanagement(void)
 140 {
 141     dissector_handle_t teimanagement_handle;
 142
 143     teimanagement_handle = create_dissector_handle(dissect_teimanagement,
 144         proto_tei);
 145     dissector_add("lapd.sapi", LAPD_SAPI_L2, teimanagement_handle);
 146 }