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  * Wireshark - Network traffic analyzer
   7  * By Gerald Combs <gerald@wireshark.org>
   8  * Copyright 1998
   9  *
  10  * SPDX-License-Identifier: GPL-2.0-or-later
  11  */
  12
  13 #include "config.h"
  14
  15 #include <epan/packet.h>
  16 #include <epan/lapd_sapi.h>
  17
  18 /* ISDN/LAPD references:
  19  *
  20  * http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/isdn.htm
  21  * http://www.ece.wpi.edu/courses/ee535/hwk11cd95/agrebe/agrebe.html
  22  * http://www.acacia-net.com/Clarinet/Protocol/q9213o84.htm
  23  */
  24
  25 void proto_reg_handoff_teimanagement(void);
  26 void proto_register_teimanagement(void);
  27
  28 static dissector_handle_t teimanagement_handle;
  29
  30 static int proto_tei;
  31
  32 static int hf_tei_management_entity_id;
  33 static int hf_tei_management_reference;
  34 static int hf_tei_management_message;
  35 static int hf_tei_management_action;
  36 static int hf_tei_management_extend;
  37
  38 static int ett_tei_management_subtree;
  39
  40 #define TEI_ID_REQUEST    0x01
  41 #define TEI_ID_ASSIGNED   0x02
  42 #define TEI_ID_DENIED     0x03
  43 #define TEI_ID_CHECK_REQ  0x04
  44 #define TEI_ID_CHECK_RESP 0x05
  45 #define TEI_ID_REMOVE     0x06
  46 #define TEI_ID_VERIFY     0x07
  47
  48 static const value_string tei_msg_vals[]={
  49     { TEI_ID_REQUEST,    "Identity Request"},
  50     { TEI_ID_ASSIGNED,   "Identity Assigned"},
  51     { TEI_ID_DENIED,     "Identity Denied"},
  52     { TEI_ID_CHECK_REQ,  "Identity Check Request"},
  53     { TEI_ID_CHECK_RESP, "Identity Check Response"},
  54     { TEI_ID_REMOVE,     "Identity Remove"},
  55     { TEI_ID_VERIFY,     "Identity Verify"},
  56     { 0, NULL}
  57 };
  58
  59 static int
  60 dissect_teimanagement(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
  61 {
  62     proto_tree *tei_tree = NULL;
  63     proto_item *tei_ti;
  64     uint8_t message;
  65
  66     col_set_str(pinfo->cinfo, COL_PROTOCOL, "TEI");
  67     col_clear(pinfo->cinfo, COL_INFO);
  68
  69     if (tree) {
  70         tei_ti = proto_tree_add_item(tree, proto_tei, tvb, 0, 5, ENC_NA);
  71         tei_tree = proto_item_add_subtree(tei_ti, ett_tei_management_subtree);
  72
  73         proto_tree_add_item(tei_tree, hf_tei_management_entity_id, tvb, 0, 1, ENC_BIG_ENDIAN);
  74         proto_tree_add_item(tei_tree, hf_tei_management_reference,  tvb, 1, 2, ENC_BIG_ENDIAN);
  75     }
  76
  77     message = tvb_get_uint8(tvb, 3);
  78         col_add_str(pinfo->cinfo, COL_INFO,
  79             val_to_str(message, tei_msg_vals, "Unknown message type (0x%04x)"));
  80     if (tree) {
  81         proto_tree_add_uint(tei_tree, hf_tei_management_message, tvb, 3, 1, message);
  82         proto_tree_add_item(tei_tree, hf_tei_management_action, tvb, 4, 1, ENC_BIG_ENDIAN);
  83         proto_tree_add_item(tei_tree, hf_tei_management_extend, tvb, 4, 1, ENC_BIG_ENDIAN);
  84     }
  85     return tvb_captured_length(tvb);
  86 }
  87
  88 void
  89 proto_register_teimanagement(void)
  90 {
  91     static int *ett[]={
  92         &ett_tei_management_subtree
  93     };
  94
  95     static hf_register_info hf[] = {
  96         { &hf_tei_management_entity_id,
  97           { "Entity", "tei_management.entity", FT_UINT8, BASE_HEX, NULL, 0x0,
  98                 "Layer Management Entity Identifier", HFILL }},
  99
 100         { &hf_tei_management_reference,
 101           { "Reference", "tei_management.reference", FT_UINT16, BASE_DEC, NULL, 0x0,
 102                 "Reference Number", HFILL }},
 103
 104         { &hf_tei_management_message,
 105           { "Msg", "tei_management.msg", FT_UINT8, BASE_DEC, VALS(tei_msg_vals), 0x0,
 106                 "Message Type", HFILL }},
 107
 108         { &hf_tei_management_action,
 109           { "Action", "tei_management.action", FT_UINT8, BASE_DEC, NULL, 0xfe,
 110                 "Action Indicator", HFILL }},
 111
 112         { &hf_tei_management_extend,
 113           { "Extend", "tei_management.extend", FT_UINT8, BASE_DEC, NULL, 0x01,
 114                 "Extension Indicator", HFILL }}
 115     };
 116
 117     proto_tei = proto_register_protocol("TEI Management Procedure, Channel D (LAPD)",
 118                                          "TEI_MANAGEMENT", "tei_management");
 119     proto_register_field_array (proto_tei, hf, array_length(hf));
 120     proto_register_subtree_array(ett, array_length(ett));
 121
 122     teimanagement_handle = register_dissector("tei_management", dissect_teimanagement, proto_tei);
 123 }
 124
 125 void
 126 proto_reg_handoff_teimanagement(void)
 127 {
 128     dissector_add_uint("lapd.sapi", LAPD_SAPI_L2, teimanagement_handle);
 129 }
 130
 131 /*
 132  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 133  *
 134  * Local variables:
 135  * c-basic-offset: 4
 136  * tab-width: 8
 137  * indent-tabs-mode: nil
 138  * End:
 139  *
 140  * vi: set shiftwidth=4 tabstop=8 expandtab:
 141  * :indentSize=4:tabSize=8:noTabs=true:
 142  */