2 * Routines for dissecting wireless ids packets sent from a Cisco
3 * access point to the WLSE (or whatever)
7 * Copyright 2006 Joerg Mayer (see AUTHORS file)
9 * Wireshark - Network traffic analyzer
10 * By Gerald Combs <gerald@wireshark.org>
11 * Copyright 1998 Gerald Combs
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version 2
16 * of the License, or (at your option) any later version.
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 * GNU General Public License for more details.
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software
25 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
28 /* With current IOS, you can use Cisco wireless Bridges/APs as
29 * wireless sniffers and configure them to send the data to some
31 * interface dot11Radio 0
32 * station-role scanner
33 * monitor frames endpoint ip address 172.22.1.1 port 8999 truncate 2312
34 * These frames are raw, i.e. they don't have a pcap header.
35 * Running wireshark at the receiving end will provide those.
39 * - Find out more about the contents of the capture header
40 * - Protect the address fields etc (all columns?)
41 * - Create subelements and put each header and packet into it
42 * - fuzz-test the dissector
43 * - Find some heuristic to detect the packet automagically and
44 * convert dissector into a heuristic dissector
45 * - Is the TRY/CATCH stuff OK?
53 #include <epan/packet.h>
54 #include <epan/etypes.h>
55 #include <epan/expert.h>
56 #include <epan/prefs.h>
58 static guint global_udp_port = 0;
60 static int proto_cwids = -1;
61 static int hf_cwids_version = -1;
62 static int hf_cwids_unknown1 = -1;
63 static int hf_cwids_channel = -1;
64 static int hf_cwids_unknown2 = -1;
65 static int hf_cwids_reallength = -1;
66 static int hf_cwids_capturelen = -1;
67 static int hf_cwids_unknown3 = -1;
69 static gint ett_cwids = -1;
71 static dissector_handle_t ieee80211_handle;
74 dissect_cwids(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
77 proto_tree *ti, *cwids_tree;
78 volatile int offset = 0;
82 col_set_str(pinfo->cinfo, COL_PROTOCOL, "CWIDS");
83 col_set_str(pinfo->cinfo, COL_INFO, "Cwids: ");
84 /* FIXME: col_set_fence(pinfo->cinfo, all-cols, only addr-cols?); */
88 while(tvb_length_remaining(tvb, offset) > 0) {
89 ti = proto_tree_add_item(tree, proto_cwids, tvb, offset, 28, ENC_NA);
90 cwids_tree = proto_item_add_subtree(ti, ett_cwids);
92 proto_tree_add_item(cwids_tree, hf_cwids_version, tvb, offset, 2, ENC_BIG_ENDIAN);
94 proto_tree_add_item(cwids_tree, hf_cwids_unknown1, tvb, offset, 7, ENC_NA);
96 proto_tree_add_item(cwids_tree, hf_cwids_channel, tvb, offset, 1, ENC_BIG_ENDIAN);
98 proto_tree_add_item(cwids_tree, hf_cwids_unknown2, tvb, offset, 6, ENC_NA);
100 proto_tree_add_item(cwids_tree, hf_cwids_reallength, tvb, offset, 2, ENC_BIG_ENDIAN);
102 capturelen = tvb_get_ntohs(tvb, offset);
103 proto_tree_add_item(cwids_tree, hf_cwids_capturelen, tvb, offset, 2, ENC_BIG_ENDIAN);
105 proto_tree_add_item(cwids_tree, hf_cwids_unknown3, tvb, offset, 8, ENC_NA);
108 wlan_tvb = tvb_new_subset(tvb, offset, capturelen, capturelen);
109 /* Continue after ieee80211 dissection errors */
110 pd_save = pinfo->private_data;
112 call_dissector(ieee80211_handle, wlan_tvb, pinfo, tree);
113 } CATCH2(BoundsError, ReportedBoundsError) {
115 expert_add_info_format(pinfo, NULL,
116 PI_MALFORMED, PI_ERROR,
117 "Malformed or short IEEE80211 subpacket");
119 /* Restore the private_data structure in case one of the
120 * called dissectors modified it (and, due to the exception,
121 * was unable to restore it).
123 pinfo->private_data = pd_save;
125 col_append_str(pinfo->cinfo, COL_INFO,
126 " [Malformed or short IEEE80211 subpacket] " );
127 col_set_fence(pinfo->cinfo, COL_INFO);
129 wlan_tvb = tvb_new_subset(tvb, offset, capturelen, capturelen);
130 /* FIXME: Why does this throw an exception? */
131 proto_tree_add_text(cwids_tree, wlan_tvb, offset, capturelen,
132 "[Malformed or short IEEE80211 subpacket]");
134 tvb_new_subset(tvb, offset, capturelen, capturelen);
139 offset += capturelen;
143 void proto_register_cwids(void);
144 void proto_reg_handoff_cwids(void);
147 proto_register_cwids(void)
149 static hf_register_info hf[] = {
151 { "Capture Version", "cwids.version", FT_UINT16, BASE_DEC, NULL,
152 0x0, "Version or format of record", HFILL }},
154 { &hf_cwids_unknown1,
155 { "Unknown1", "cwids.unknown1", FT_BYTES, BASE_NONE, NULL,
156 0x0, "1st Unknown block - timestamp?", HFILL }},
159 { "Channel", "cwids.channel", FT_UINT8, BASE_DEC, NULL,
160 0x0, "Channel for this capture", HFILL }},
162 { &hf_cwids_unknown2,
163 { "Unknown2", "cwids.unknown2", FT_BYTES, BASE_NONE, NULL,
164 0x0, "2nd Unknown block", HFILL }},
166 { &hf_cwids_reallength,
167 { "Original length", "cwids.reallen", FT_UINT16, BASE_DEC, NULL,
168 0x0, "Original num bytes in frame", HFILL }},
170 { &hf_cwids_capturelen,
171 { "Capture length", "cwids.caplen", FT_UINT16, BASE_DEC, NULL,
172 0x0, "Captured bytes in record", HFILL }},
174 { &hf_cwids_unknown3,
175 { "Unknown3", "cwids.unknown3", FT_BYTES, BASE_NONE, NULL,
176 0x0, "3rd Unknown block", HFILL }},
179 static gint *ett[] = {
183 module_t *cwids_module;
185 proto_cwids = proto_register_protocol("Cisco Wireless IDS Captures", "CWIDS", "cwids");
186 proto_register_field_array(proto_cwids, hf, array_length(hf));
187 proto_register_subtree_array(ett, array_length(ett));
189 cwids_module = prefs_register_protocol(proto_cwids, proto_reg_handoff_cwids);
190 prefs_register_uint_preference(cwids_module, "udp.port",
192 "Set the destination UDP port Cisco wireless IDS messages",
193 10, &global_udp_port);
198 proto_reg_handoff_cwids(void)
200 static dissector_handle_t cwids_handle;
201 static guint saved_udp_port;
202 static gboolean initialized = FALSE;
205 cwids_handle = create_dissector_handle(dissect_cwids, proto_cwids);
206 dissector_add_handle("udp.port", cwids_handle);
207 ieee80211_handle = find_dissector("wlan");
210 if (saved_udp_port != 0) {
211 dissector_delete_uint("udp.port", saved_udp_port, cwids_handle);
214 if (global_udp_port != 0) {
215 dissector_add_uint("udp.port", global_udp_port, cwids_handle);
217 saved_udp_port = global_udp_port;