epan/dissectors/packet-trel.c

   1 /* packet-trel.c
   2  * Routines for TREL packet dissection
   3  * Copyright 2004, Pranay Nagpure  - <pranay.dilip@graniteriverlabs.in>
   4  *
   5  * Wireshark - Network traffic analyzer
   6  * By Gerald Combs <gerald@wireshark.org>
   7  * Copyright 1998 Gerald Combs
   8  *
   9  * SPDX-License-Identifier: GPL-2.0-or-later
  10  */
  11
  12
  13 #include "config.h"
  14 #include <epan/packet.h>
  15 #include "packet-ieee802154.h"
  16 #include <epan/wmem_scopes.h>
  17 #include <epan/packet_info.h>
  18 #include <epan/proto_data.h>
  19 #include <epan/proto.h>
  20 #include <packet-mle.h>
  21 #include <packet-6lowpan.h>
  22 #include <epan/expert.h>
  23 #include<wsutil/wsgcrypt.h>
  24
  25 #define TREL_PORT 38196
  26
  27 #define  TREL_TYPE_BROADCAST 0
  28 #define TREL_TYPE_UNICAST    1
  29 #define TREL_TYPE_ACK        2
  30
  31 static dissector_handle_t trel_handle;
  32 static int hf_trel_version;
  33 static int hf_trel_rsv;
  34 static int hf_trel_ack;
  35 static int hf_trel_type;
  36 static int hf_trel_channel;
  37 static int hf_802154_dest_panid;
  38 static int hf_trel_source_addr;
  39 static int hf_trel_destination_addr;
  40 static int hf_trel_packetno;
  41
  42 static int proto_trel;
  43
  44 static int ett_trel;
  45 static int ett_trel_hdr;
  46
  47 void proto_register_trel(void);
  48
  49 static const value_string trel_command_vals[] = {
  50     { TREL_TYPE_BROADCAST,                "TREL Advertisement" },
  51     { TREL_TYPE_UNICAST,                  "TREL Unicast Response" },
  52     { TREL_TYPE_ACK,                      "TREL Acknowledgement"},
  53     { 0, NULL}
  54 };
  55
  56 static int
  57 dissect_trel(tvbuff_t* tvb, packet_info* pinfo, proto_tree* tree, void* data _U_)
  58 {
  59     proto_tree* volatile trel_tree = NULL, * volatile trel_hdr_tree;
  60     proto_item* volatile proto_root = NULL;
  61
  62     unsigned                offset = 0;
  63
  64     col_set_str(pinfo->cinfo, COL_PROTOCOL, "TREL");
  65     col_clear(pinfo->cinfo, COL_INFO);
  66
  67     proto_root = proto_tree_add_item(tree, proto_trel, tvb, 0, tvb_reported_length(tvb), ENC_NA);
  68     trel_tree = proto_item_add_subtree(proto_root, ett_trel);
  69
  70     //add header subtree
  71     trel_hdr_tree = proto_tree_add_subtree(trel_tree, tvb, 0, 4, ett_trel_hdr, NULL, "Header");
  72
  73     proto_tree_add_item(trel_hdr_tree, hf_trel_version, tvb, offset, 1, ENC_NA);
  74     proto_tree_add_item(trel_hdr_tree, hf_trel_rsv, tvb, offset, 1, ENC_NA);
  75     proto_tree_add_item(trel_hdr_tree, hf_trel_ack, tvb, offset, 1, ENC_NA);
  76     proto_tree_add_item(trel_hdr_tree, hf_trel_type, tvb, offset, 1, ENC_NA);
  77
  78     uint8_t type = tvb_get_uint8(tvb, offset);
  79     col_add_str(pinfo->cinfo, COL_INFO, val_to_str(type, trel_command_vals, "Unknown (%x)"));
  80     ++offset;
  81     proto_tree_add_item(trel_hdr_tree, hf_trel_channel, tvb, offset, 1, ENC_NA);
  82     ++offset;
  83
  84     proto_tree_add_item(trel_hdr_tree, hf_802154_dest_panid, tvb, offset, 2, ENC_BIG_ENDIAN);
  85     offset += 2;
  86
  87     proto_tree_add_item(trel_hdr_tree, hf_trel_packetno, tvb, offset, 4, ENC_BIG_ENDIAN);
  88     offset += 4;
  89
  90     proto_tree_add_item(trel_hdr_tree, hf_trel_source_addr, tvb, offset, 8, ENC_BIG_ENDIAN);
  91     offset += 8;
  92
  93     if (type)
  94     {
  95         proto_tree_add_item(trel_hdr_tree, hf_trel_destination_addr, tvb, offset, 8, ENC_BIG_ENDIAN);
  96         offset += 8;
  97     }
  98
  99     dissector_handle_t frame_handle = find_dissector("wpan_nofcs");
 100     tvbuff_t* payload = tvb_new_subset_remaining(tvb, offset);
 101
 102     if (tvb_reported_length(payload))
 103         call_dissector(frame_handle, payload, pinfo, trel_tree);
 104
 105     return tvb_captured_length(tvb);
 106 }
 107 // below code is added to replace mdns dissector registration
 108 static bool
 109 dissect_trel_heur(tvbuff_t* tvb, packet_info* pinfo, proto_tree* tree, void* data)
 110 {
 111     if ((tvb_captured_length(tvb)) < 16 ) {
 112         return false;
 113     }
 114
 115     uint8_t first = tvb_get_uint8(tvb, 0);
 116     if ((first & 0xE0) != 0)
 117         return false;
 118
 119     if (pinfo->srcport == pinfo->destport)      return false;
 120
 121     dissect_trel(tvb, pinfo, tree, data);
 122     return true;
 123 }
 124 void
 125 proto_register_trel(void)
 126 {
 127
 128     static hf_register_info hf[] = {
 129
 130         { &hf_trel_version,
 131           { "TREL version",
 132             "trel.ver",
 133             FT_UINT8, BASE_DEC, NULL, 0xE0,
 134             "The TREL protocol version",
 135             HFILL
 136           }
 137         },
 138         { &hf_trel_rsv,
 139           { "TREL reserved bit",
 140             "trel.rsv",
 141             FT_UINT8, BASE_DEC, NULL, 0x18,
 142             "The TREL reserved bit",
 143             HFILL
 144           }
 145         },
 146         { &hf_trel_ack,
 147           { "TREL acknowledgement",
 148             "trel.ack",
 149             FT_UINT8, BASE_DEC, NULL, 0x4,
 150             "The TREL acknowledgement",
 151             HFILL
 152           }
 153         },
 154         { &hf_trel_type,
 155           { "TREL type",
 156             "trel.type",
 157             FT_UINT8, BASE_DEC, NULL, 0x3,
 158             "The TREL type",
 159             HFILL
 160           }
 161         },
 162         { &hf_trel_channel,
 163           { "TREL channel",
 164             "trel.channel",
 165             FT_UINT8, BASE_DEC, NULL, 0x0,
 166             "The TREL channel",
 167             HFILL
 168           }
 169         },
 170         { &hf_802154_dest_panid,
 171           { "TREL 802.15.4 Dest Pan ID",
 172             "trel.panID",
 173             FT_UINT16, BASE_DEC, NULL, 0x0,
 174             "The TREL  802.15.4 Dest Pan ID",
 175             HFILL
 176           }
 177         },
 178         { &hf_trel_packetno,
 179           { "TREL packet number",
 180             "trel.packetno",
 181             FT_UINT32, BASE_DEC, NULL, 0x0,
 182             "The TREL  packet number",
 183             HFILL
 184           }
 185         },
 186         { &hf_trel_source_addr,
 187           { "TREL Src Address",
 188              "trel.source_addr",
 189              FT_EUI64, BASE_NONE, NULL, 0x0,
 190              "Source address",
 191              HFILL
 192           }
 193         },
 194         { &hf_trel_destination_addr,
 195           { "TREL Dest Address",
 196             "trel.destination_addr",
 197             FT_EUI64, BASE_NONE, NULL, 0x0,
 198             "Destination address",
 199             HFILL
 200           }
 201         }
 202     };
 203
 204     static int* ett[] = {
 205       &ett_trel,
 206       &ett_trel_hdr
 207     };
 208
 209     proto_trel = proto_register_protocol("TREL Protocol", "TREL", "trel");
 210
 211     proto_register_field_array(proto_trel, hf, array_length(hf));
 212     proto_register_subtree_array(ett, array_length(ett));
 213
 214     trel_handle = register_dissector("trel", dissect_trel, proto_trel);
 215
 216 }
 217 void
 218 proto_reg_handoff_trel(void)
 219 {
 220     //heur dissector is disabled as it not strong enough
 221     //dissector_add_uint("udp.port", TREL_PORT, trel_handle);
 222     dissector_add_uint_with_preference("udp.port", 0, trel_handle);
 223     heur_dissector_add("udp", dissect_trel_heur, "TREL over UDP", "trel_udp", proto_trel, HEURISTIC_DISABLE);
 224 }