diff options
author | Jörg Mayer <jmayer@loplof.de> | 2006-07-06 10:58:48 +0000 |
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committer | Jörg Mayer <jmayer@loplof.de> | 2006-07-06 10:58:48 +0000 |
commit | 2c5f9183669339d37a61ca11db1ff47a46c831cc (patch) | |
tree | 05bea0faed847c4f37140b124c4d09b2c9d91f44 | |
parent | a3430f8bb1c4370f2d487f9a73c840b61edcfb65 (diff) |
New dissector for the cisco wireless ids communication protocol
(name invented by me, better suggenstions welcome).
svn path=/trunk/; revision=18671
-rw-r--r-- | epan/dissectors/Makefile.common | 1 | ||||
-rw-r--r-- | epan/dissectors/packet-cisco-wids.c | 198 |
2 files changed, 199 insertions, 0 deletions
diff --git a/epan/dissectors/Makefile.common b/epan/dissectors/Makefile.common index 55701519fc..7d061526c0 100644 --- a/epan/dissectors/Makefile.common +++ b/epan/dissectors/Makefile.common @@ -151,6 +151,7 @@ DISSECTOR_SRC = \ packet-cigi.c \ packet-cimd.c \ packet-cip.c \ + packet-cisco-wids.c \ packet-cisco-wireless.c \ packet-cisco-oui.c \ packet-clearcase.c \ diff --git a/epan/dissectors/packet-cisco-wids.c b/epan/dissectors/packet-cisco-wids.c new file mode 100644 index 0000000000..1ab5caf9ed --- /dev/null +++ b/epan/dissectors/packet-cisco-wids.c @@ -0,0 +1,198 @@ +/* packet-cwids.c + * Routines for dissecting wireless ids packets sent from a Cisco + * access point to the WLSE (or whatever) + * + * $Id$ + * + * Copyright 2006 Joerg Mayer (see AUTHORS file) + * + * Wireshark - Network traffic analyzer + * By Gerald Combs <gerald@wireshark.org> + * Copyright 1998 Gerald Combs + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +/* With current IOS, you can use Cisco wireless Bridges/APs as a + * wireless sniffers and configure them with the "monitor ..." + * command to * send the data to some central IDS. + * This dissector tries to decode those frames. + */ + +/* 2do: + * - Find out more about the contents of the capture header + * - Protect the address fields etc (all columns?) + * - Create subelements and put each header and packet into it + * - fuzz-test the dissector + * - Find some heuristic do detect the packet automagically and + * convert dissector into a heuristic dissector + * - Is the TRY/CATCH stuff OK? + */ + +#ifdef HAVE_CONFIG_H +# include "config.h" +#endif + +#include <glib.h> +#include <epan/packet.h> +#include <epan/etypes.h> +#include <epan/expert.h> +#include <epan/prefs.h> + +static guint udp_port = 0; +void proto_reg_handoff_cwids(void); + + +static int proto_cwids = -1; +static int hf_cwids_version = -1; +static int hf_cwids_unknown1 = -1; +static int hf_cwids_reallength = -1; +static int hf_cwids_capturelen = -1; +static int hf_cwids_unknown2 = -1; +static int hf_cwids_trailer = -1; + +static gint ett_cwids = -1; + +static dissector_handle_t ieee80211_handle; + +static void +dissect_cwids(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) +{ + tvbuff_t *wlan_tvb; + proto_tree *ti, *cwids_tree; + int offset = 0; + guint16 capturelen; + guint remain; + + if (check_col(pinfo->cinfo, COL_PROTOCOL)) + col_set_str(pinfo->cinfo, COL_PROTOCOL, "CWIDS"); + if (check_col(pinfo->cinfo, COL_INFO)) + col_clear(pinfo->cinfo, COL_INFO); + + if (check_col(pinfo->cinfo, COL_INFO)) { + col_add_fstr(pinfo->cinfo, COL_INFO, "Cwids: "); + } + /* FIXME: col_set_fence(pinfo->cinfo, all-cols, only addr-cols?); */ + + cwids_tree = NULL; + + while((remain = tvb_length_remaining(tvb, offset)) >= 28) { + ti = proto_tree_add_item(tree, proto_cwids, tvb, offset, 28, FALSE); + cwids_tree = proto_item_add_subtree(ti, ett_cwids); + + proto_tree_add_item(cwids_tree, hf_cwids_version, tvb, offset, 2, FALSE); + offset += 2; + proto_tree_add_item(cwids_tree, hf_cwids_unknown1, tvb, offset, 14, FALSE); + offset += 14; + proto_tree_add_item(cwids_tree, hf_cwids_reallength, tvb, offset, 2, FALSE); + offset += 2; + capturelen = tvb_get_ntohs(tvb, offset); + proto_tree_add_item(cwids_tree, hf_cwids_capturelen, tvb, offset, 2, FALSE); + offset += 2; + proto_tree_add_item(cwids_tree, hf_cwids_unknown2, tvb, offset, 8, FALSE); + offset += 8; + + wlan_tvb = tvb_new_subset(tvb, offset, capturelen, capturelen); + /* Continue after ieee80211 dissection errors */ + TRY { + call_dissector(ieee80211_handle, wlan_tvb, pinfo, tree); + } CATCH2(BoundsError, ReportedBoundsError) { + + expert_add_info_format(pinfo, NULL, + PI_MALFORMED, PI_ERROR, + "Malformed or short IEEE80211 subpacket"); + + if (check_col(pinfo->cinfo, COL_INFO)) { + col_append_str(pinfo->cinfo, COL_INFO, + " [Malformed or short IEEE80211 subpacket] " ); + col_set_fence(pinfo->cinfo, COL_INFO); + } + + wlan_tvb = tvb_new_subset(tvb, offset, capturelen, capturelen); +#if 0 + /* FIXME: Why does this throw an exception? */ + proto_tree_add_text(cwids_tree, wlan_tvb, offset, capturelen, + "[Malformed or short IEEE80211 subpacket]"); +#endif + ; + } ENDTRY; + + offset += capturelen; + } + if (remain > 0) { /* FIXME: Shouldn't happen? */ + ti = proto_tree_add_item(tree, proto_cwids, tvb, offset, remain, FALSE); + cwids_tree = proto_item_add_subtree(ti, ett_cwids); + + proto_tree_add_item(cwids_tree, hf_cwids_trailer, tvb, offset, remain, FALSE); + } +} + +void +proto_register_cwids(void) +{ + static hf_register_info hf[] = { + { &hf_cwids_version, + { "Capture Version", "cwids.version", FT_UINT16, BASE_DEC, NULL, + 0x0, "Version or format of record", HFILL }}, + + { &hf_cwids_unknown1, + { "Unknown1", "cwids.unknown1", FT_BYTES, BASE_NONE, NULL, + 0x0, "1st Unknown block", HFILL }}, + + { &hf_cwids_reallength, + { "Original length", "cwids.reallen", FT_UINT16, BASE_DEC, NULL, + 0x0, "Original num bytes in frame", HFILL }}, + + { &hf_cwids_capturelen, + { "Capture length", "cwids.caplen", FT_UINT16, BASE_DEC, NULL, + 0x0, "Captured bytes in record", HFILL }}, + + { &hf_cwids_unknown2, + { "Unknown2", "cwids.unknown2", FT_BYTES, BASE_NONE, NULL, + 0x0, "2nd Unknown block", HFILL }}, + + { &hf_cwids_trailer, + { "Trailer", "cwids.trailer", FT_BYTES, BASE_NONE, NULL, + 0x0, "CWIDS trailer", HFILL }}, + }; + static gint *ett[] = { + &ett_cwids, + }; + + module_t *cwids_module; + + proto_cwids = proto_register_protocol("Cisco Wireless IDS Captures", "CWIDS", "cwids"); + proto_register_field_array(proto_cwids, hf, array_length(hf)); + proto_register_subtree_array(ett, array_length(ett)); + + cwids_module = prefs_register_protocol(proto_cwids, proto_reg_handoff_cwids); + prefs_register_uint_preference(cwids_module, "udp.port", + "CWIDS port", + "Set the destination UDP port Cisco wireless IDS messages", + 10, &udp_port); + +} + +void +proto_reg_handoff_cwids(void) +{ + dissector_handle_t cwids_handle; + + ieee80211_handle = find_dissector("wlan"); + + cwids_handle = create_dissector_handle(dissect_cwids, proto_cwids); + dissector_add("udp.port", udp_port, cwids_handle); +} + |