epan/dissectors/packet-dxl.c

   1 /* packet-dxl.c
   2  *
   3  * Routines for DXL dissection
   4  * Github projects:
   5  *  https://github.com/opendxl
   6  *
   7  * Copyright 2018, Dario Lombardo <lomato@gmail.com>
   8  *
   9  * Wireshark - Network traffic analyzer
  10  * By Gerald Combs <gerald@wireshark.org>
  11  * Copyright 1998 Gerald Combs
  12  *
  13  * SPDX-License-Identifier: GPL-2.0-or-later
  14  */
  15
  16 #include "config.h"
  17
  18 #include <epan/packet.h>
  19 #include <epan/tvbuff.h>
  20 #include <epan/expert.h>
  21
  22 void proto_register_dxl(void);
  23 void proto_reg_handoff_dxl(void);
  24
  25 static int proto_dxl;
  26
  27 static int hf_dxl_version;
  28 static int hf_dxl_type;
  29
  30 static int ett_dxl;
  31
  32 static expert_field ei_dxl_unsupported;
  33
  34 static dissector_handle_t msgpack_handle;
  35
  36 #define DXL_REQUEST 0
  37 #define DXL_RESPONSE 1
  38 #define DXL_EVENT 2
  39 #define DXL_ERROR 3
  40
  41 static const value_string dxl_message_types[] = {
  42         { DXL_REQUEST, "Request" },
  43         { DXL_RESPONSE, "Response" },
  44         { DXL_EVENT, "Event" },
  45         { DXL_ERROR, "Error" },
  46         { 0, NULL }
  47 };
  48
  49 static void dissect_dxl_event(tvbuff_t* tvb, packet_info* pinfo, proto_tree* dxl_tree, int* offset)
  50 {
  51         tvbuff_t* tvb_msgpack;
  52
  53         tvb_msgpack = tvb_new_subset_remaining(tvb, *offset);
  54         *offset = call_dissector_with_data(msgpack_handle, tvb_msgpack, pinfo, dxl_tree, "Message ID");
  55
  56         tvb_msgpack = tvb_new_subset_remaining(tvb_msgpack, *offset);
  57         *offset = call_dissector_with_data(msgpack_handle, tvb_msgpack, pinfo, dxl_tree, "Client ID");
  58
  59         tvb_msgpack = tvb_new_subset_remaining(tvb_msgpack, *offset);
  60         *offset = call_dissector_with_data(msgpack_handle, tvb_msgpack, pinfo, dxl_tree, "Source Broker ID");
  61
  62         tvb_msgpack = tvb_new_subset_remaining(tvb_msgpack, *offset);
  63         *offset = call_dissector_with_data(msgpack_handle, tvb_msgpack, pinfo, dxl_tree, "Broker IDs");
  64
  65         tvb_msgpack = tvb_new_subset_remaining(tvb_msgpack, *offset);
  66         *offset = call_dissector_with_data(msgpack_handle, tvb_msgpack, pinfo, dxl_tree, "Client IDs");
  67
  68         tvb_msgpack = tvb_new_subset_remaining(tvb_msgpack, *offset);
  69         *offset = call_dissector_with_data(msgpack_handle, tvb_msgpack, pinfo, dxl_tree, "Payload");
  70
  71         tvb_msgpack = tvb_new_subset_remaining(tvb_msgpack, *offset);
  72         *offset = call_dissector_with_data(msgpack_handle, tvb_msgpack, pinfo, dxl_tree, "Reply to topic");
  73
  74         tvb_msgpack = tvb_new_subset_remaining(tvb_msgpack, *offset);
  75         *offset = call_dissector_with_data(msgpack_handle, tvb_msgpack, pinfo, dxl_tree, "Service ID");
  76 }
  77
  78 static int dissect_dxl(tvbuff_t* tvb, packet_info* pinfo, proto_tree* tree, void* data _U_)
  79 {
  80         int offset = 0;
  81         proto_item* ti;
  82         proto_tree* dxl_tree;
  83         uint8_t type;
  84
  85         ti = proto_tree_add_item(tree, proto_dxl, tvb, 0, -1, ENC_NA);
  86         dxl_tree = proto_item_add_subtree(ti, ett_dxl);
  87
  88         proto_tree_add_item(dxl_tree, hf_dxl_version, tvb, offset, 1, ENC_NA);
  89         offset += 1;
  90
  91         type = tvb_get_uint8(tvb, offset);
  92
  93         proto_tree_add_item(dxl_tree, hf_dxl_type, tvb, offset, 1, ENC_NA);
  94         offset += 1;
  95
  96         switch (type) {
  97                 case DXL_REQUEST:
  98                 case DXL_RESPONSE:
  99                 case DXL_ERROR:
 100                         expert_add_info_format(pinfo, tree, &ei_dxl_unsupported, "Type 0x%x is unsupported", type);
 101                         break;
 102                 case DXL_EVENT:
 103                         dissect_dxl_event(tvb, pinfo, dxl_tree, &offset);
 104                         break;
 105         }
 106
 107         return offset;
 108 }
 109
 110 void proto_reg_handoff_dxl(void)
 111 {
 112         msgpack_handle = find_dissector("msgpack");
 113 }
 114
 115 void proto_register_dxl(void)
 116 {
 117         expert_module_t* expert_dxl;
 118
 119         static hf_register_info hf[] = {
 120                 { &hf_dxl_version,
 121                         { "Version", "dxl.version", FT_UINT8, BASE_DEC, NULL, 0x00, NULL, HFILL }
 122                 },
 123                 { &hf_dxl_type,
 124                         { "Type", "dxl.type", FT_UINT8, BASE_HEX, VALS(dxl_message_types), 0x00, NULL, HFILL }
 125                 }
 126         };
 127
 128         static int* ett[] = {
 129                 &ett_dxl
 130         };
 131
 132         proto_dxl = proto_register_protocol("Data Exchange Layer", "DXL", "dxl");
 133         register_dissector("dxl", dissect_dxl, proto_dxl);
 134
 135         proto_register_field_array(proto_dxl, hf, array_length(hf));
 136         proto_register_subtree_array(ett, array_length(ett));
 137
 138         static ei_register_info ei[] = {
 139                 { &ei_dxl_unsupported, { "dxl.type.unsupported", PI_UNDECODED, PI_WARN, "Unsupported DXL message", EXPFILL }}
 140         };
 141
 142         expert_dxl = expert_register_protocol(proto_dxl);
 143         expert_register_field_array(expert_dxl, ei, array_length(ei));
 144 }
 145
 146 /*
 147  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 148  *
 149  * Local variables:
 150  * c-basic-offset: 8
 151  * tab-width: 8
 152  * indent-tabs-mode: t
 153  * End:
 154  *
 155  * vi: set shiftwidth=8 tabstop=8 noexpandtab:
 156  * :indentSize=8:tabSize=8:noTabs=false:
 157  */