2 * Routines for EAPOL 802.1X authentication header disassembly
3 * (From IEEE Draft P802.1X/D11; is there a later draft, or a
4 * final standard? If so, check it.)
6 * $Id: packet-eapol.c,v 1.16 2003/11/13 23:38:32 guy Exp $
8 * Ethereal - Network traffic analyzer
9 * By Gerald Combs <gerald@ethereal.com>
10 * Copyright 1998 Gerald Combs
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version 2
15 * of the License, or (at your option) any later version.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
32 #include <epan/packet.h>
33 #include "packet-ieee80211.h"
36 static int proto_eapol = -1;
37 static int hf_eapol_version = -1;
38 static int hf_eapol_type = -1;
39 static int hf_eapol_len = -1;
40 static int hf_eapol_keydes_type = -1;
41 static int hf_eapol_keydes_keylen = -1;
42 static int hf_eapol_keydes_replay_counter = -1;
43 static int hf_eapol_keydes_key_iv = -1;
44 static int hf_eapol_keydes_key_index_keytype = -1;
45 static int hf_eapol_keydes_key_index_indexnum = -1;
46 static int hf_eapol_keydes_key_signature = -1;
47 static int hf_eapol_keydes_key = -1;
49 static int hf_eapol_wpa_keydes_keyinfo = -1;
50 static int hf_eapol_wpa_keydes_keyinfo_keydes_ver = -1;
51 static int hf_eapol_wpa_keydes_keyinfo_key_type = -1;
52 static int hf_eapol_wpa_keydes_keyinfo_key_index = -1;
53 static int hf_eapol_wpa_keydes_keyinfo_install = -1;
54 static int hf_eapol_wpa_keydes_keyinfo_key_ack = -1;
55 static int hf_eapol_wpa_keydes_keyinfo_key_mic = -1;
56 static int hf_eapol_wpa_keydes_keyinfo_secure = -1;
57 static int hf_eapol_wpa_keydes_keyinfo_error = -1;
58 static int hf_eapol_wpa_keydes_keyinfo_request = -1;
59 static int hf_eapol_wpa_keydes_nonce = -1;
60 static int hf_eapol_wpa_keydes_rsc = -1;
61 static int hf_eapol_wpa_keydes_id = -1;
62 static int hf_eapol_wpa_keydes_mic = -1;
63 static int hf_eapol_wpa_keydes_datalen = -1;
64 static int hf_eapol_wpa_keydes_data = -1;
66 static gint ett_eapol = -1;
67 static gint ett_eapol_keydes_data = -1;
68 static gint ett_eapol_key_index = -1;
69 static gint ett_keyinfo = -1;
71 static dissector_handle_t eap_handle;
72 static dissector_handle_t data_handle;
74 #define EAPOL_HDR_LEN 4
78 #define EAPOL_LOGOFF 2
80 #define EAPOL_ENCAP_ASF_ALERT 4
82 #define EAPOL_WPA_KEY 254
84 static const value_string eapol_type_vals[] = {
85 { EAP_PACKET, "EAP Packet" },
86 { EAPOL_START, "Start" },
87 { EAPOL_LOGOFF, "Logoff" },
89 { EAPOL_ENCAP_ASF_ALERT, "Encapsulated ASF Alert" },
93 static const value_string eapol_keydes_type_vals[] = {
94 { 1, "RC4 Descriptor" },
95 { EAPOL_WPA_KEY, "EAPOL WPA key" },
99 #define KEY_INFO_KEYDES_VER_MASK 0x0007
100 #define KEY_INFO_KEY_TYPE_MASK 0x0008
101 #define KEY_INFO_KEY_INDEX_MASK 0x0030
102 #define KEY_INFO_INSTALL_MASK 0x0040
103 #define KEY_INFO_KEY_ACK_MASK 0x0080
104 #define KEY_INFO_KEY_MIC_MASK 0x0100
105 #define KEY_INFO_SECURE_MASK 0x0200
106 #define KEY_INFO_ERROR_MASK 0x0400
107 #define KEY_INFO_REQUEST_MASK 0x0800
109 static const true_false_string keytype_tfs =
110 { "Unicast", "Broadcast" };
111 static const true_false_string tfs_keyinfo_key_type =
112 { "Pairwise key", "Group key" };
113 #define KEYDES_VER_TYPE1 0x01
114 #define KEYDES_VER_TYPE2 0x02
115 static const value_string keydes_ver[] = {
116 { KEYDES_VER_TYPE1, "HMAC-MD5 for MIC and RC4 for encryption" },
117 { KEYDES_VER_TYPE2, "AES-CBC-MAC for MIC and HMAC-SHA1 for encryption" },
122 dissect_eapol(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
129 guint16 eapol_key_len, eapol_data_len;
132 proto_tree *ti = NULL;
133 proto_tree *eapol_tree = NULL;
134 proto_tree *keyinfo_item = NULL;
135 proto_tree *keyinfo_tree = NULL;
136 proto_tree *key_index_tree, *keydes_tree;
139 if (check_col(pinfo->cinfo, COL_PROTOCOL))
140 col_set_str(pinfo->cinfo, COL_PROTOCOL, "EAPOL");
141 if (check_col(pinfo->cinfo, COL_INFO))
142 col_clear(pinfo->cinfo, COL_INFO);
145 ti = proto_tree_add_item(tree, proto_eapol, tvb, 0, -1, FALSE);
146 eapol_tree = proto_item_add_subtree(ti, ett_eapol);
148 proto_tree_add_item(eapol_tree, hf_eapol_version, tvb, offset, 1, FALSE);
152 eapol_type = tvb_get_guint8(tvb, offset);
154 proto_tree_add_uint(eapol_tree, hf_eapol_type, tvb, offset, 1, eapol_type);
155 if (check_col(pinfo->cinfo, COL_INFO))
156 col_add_str(pinfo->cinfo, COL_INFO,
157 val_to_str(eapol_type, eapol_type_vals, "Unknown type (0x%02X)"));
160 eapol_len = tvb_get_ntohs(tvb, offset);
161 len = EAPOL_HDR_LEN + eapol_len;
162 set_actual_length(tvb, len);
164 proto_item_set_len(ti, len);
165 proto_tree_add_uint(eapol_tree, hf_eapol_len, tvb, offset, 2, eapol_len);
169 switch (eapol_type) {
172 next_tvb = tvb_new_subset(tvb, offset, -1, -1);
173 call_dissector(eap_handle, next_tvb, pinfo, eapol_tree);
178 keydesc_type = tvb_get_guint8(tvb, offset);
179 proto_tree_add_item(eapol_tree, hf_eapol_keydes_type, tvb, offset, 1, FALSE);
181 if (keydesc_type == EAPOL_WPA_KEY) {
182 keyinfo = tvb_get_ntohs(tvb, offset);
184 proto_tree_add_uint(eapol_tree, hf_eapol_wpa_keydes_keyinfo, tvb,
187 keyinfo_tree = proto_item_add_subtree(keyinfo_item, ett_keyinfo);
188 proto_tree_add_uint(keyinfo_tree, hf_eapol_wpa_keydes_keyinfo_keydes_ver, tvb, offset, 2, keyinfo);
189 proto_tree_add_boolean(keyinfo_tree, hf_eapol_wpa_keydes_keyinfo_key_type, tvb, offset, 2, keyinfo);
190 proto_tree_add_uint(keyinfo_tree, hf_eapol_wpa_keydes_keyinfo_key_index, tvb, offset, 2, keyinfo);
191 proto_tree_add_boolean(keyinfo_tree, hf_eapol_wpa_keydes_keyinfo_install, tvb, offset, 2, keyinfo);
192 proto_tree_add_boolean(keyinfo_tree, hf_eapol_wpa_keydes_keyinfo_key_ack, tvb, offset, 2, keyinfo);
193 proto_tree_add_boolean(keyinfo_tree, hf_eapol_wpa_keydes_keyinfo_key_mic, tvb, offset, 2, keyinfo);
194 proto_tree_add_boolean(keyinfo_tree, hf_eapol_wpa_keydes_keyinfo_secure, tvb, offset, 2, keyinfo);
195 proto_tree_add_boolean(keyinfo_tree, hf_eapol_wpa_keydes_keyinfo_error, tvb, offset, 2, keyinfo);
196 proto_tree_add_boolean(keyinfo_tree, hf_eapol_wpa_keydes_keyinfo_request, tvb, offset, 2, keyinfo);
199 proto_tree_add_uint(eapol_tree, hf_eapol_keydes_keylen, tvb, offset,
200 2, tvb_get_ntohs(tvb, offset));
202 proto_tree_add_item(eapol_tree, hf_eapol_keydes_replay_counter, tvb,
205 proto_tree_add_item(eapol_tree, hf_eapol_wpa_keydes_nonce, tvb, offset,
208 proto_tree_add_item(eapol_tree, hf_eapol_keydes_key_iv, tvb,
211 proto_tree_add_item(eapol_tree, hf_eapol_wpa_keydes_rsc, tvb, offset,
214 proto_tree_add_item(eapol_tree, hf_eapol_wpa_keydes_id, tvb, offset, 8,
217 proto_tree_add_item(eapol_tree, hf_eapol_wpa_keydes_mic, tvb, offset,
220 eapol_data_len = tvb_get_ntohs(tvb, offset);
221 proto_tree_add_uint(eapol_tree, hf_eapol_wpa_keydes_datalen, tvb,
222 offset, 2, eapol_data_len);
224 if (eapol_data_len != 0) {
225 ti = proto_tree_add_item(eapol_tree, hf_eapol_wpa_keydes_data,
226 tvb, offset, eapol_data_len, FALSE);
227 keydes_tree = proto_item_add_subtree(ti, ett_eapol_keydes_data);
228 ieee_80211_add_tagged_parameters(tvb, offset, keydes_tree,
233 eapol_key_len = tvb_get_ntohs(tvb, offset);
234 proto_tree_add_uint(eapol_tree, hf_eapol_keydes_keylen, tvb, offset, 2, eapol_key_len);
236 proto_tree_add_item(eapol_tree, hf_eapol_keydes_replay_counter, tvb,
239 proto_tree_add_item(eapol_tree, hf_eapol_keydes_key_iv, tvb,
242 key_index = tvb_get_guint8(tvb, offset);
243 ti = proto_tree_add_text(eapol_tree, tvb, offset, 1,
244 "Key Index: %s, index %u",
245 (key_index & 0x80) ? "unicast" : "broadcast",
247 key_index_tree = proto_item_add_subtree(ti, ett_eapol_key_index);
248 proto_tree_add_boolean(eapol_tree, hf_eapol_keydes_key_index_keytype,
249 tvb, offset, 1, key_index);
250 proto_tree_add_uint(eapol_tree, hf_eapol_keydes_key_index_indexnum,
251 tvb, offset, 1, key_index);
253 proto_tree_add_item(eapol_tree, hf_eapol_keydes_key_signature, tvb,
256 if (eapol_key_len != 0)
257 proto_tree_add_item(eapol_tree, hf_eapol_keydes_key, tvb, offset,
258 eapol_key_len, FALSE);
263 case EAPOL_ENCAP_ASF_ALERT: /* XXX - is this an SNMP trap? */
265 next_tvb = tvb_new_subset(tvb, offset, -1, -1);
266 call_dissector(data_handle, next_tvb, pinfo, eapol_tree);
272 proto_register_eapol(void)
274 static hf_register_info hf[] = {
275 { &hf_eapol_version, {
276 "Version", "eapol.version", FT_UINT8, BASE_DEC,
277 NULL, 0x0, "", HFILL }},
279 "Type", "eapol.type", FT_UINT8, BASE_DEC,
280 VALS(eapol_type_vals), 0x0, "", HFILL }},
282 "Length", "eapol.len", FT_UINT16, BASE_DEC,
283 NULL, 0x0, "Length", HFILL }},
284 { &hf_eapol_keydes_type, {
285 "Descriptor Type", "eapol.keydes.type", FT_UINT8, BASE_DEC,
286 VALS(eapol_keydes_type_vals), 0x0, "Key Descriptor Type", HFILL }},
287 { &hf_eapol_keydes_keylen, {
288 "Key Length", "eapol.keydes.keylen", FT_UINT16, BASE_DEC,
289 NULL, 0x0, "Key Length", HFILL }},
290 { &hf_eapol_keydes_replay_counter, {
291 "Replay Counter", "eapol.keydes.replay_counter", FT_UINT64, BASE_DEC,
292 NULL, 0x0, "Replay Counter", HFILL }},
293 { &hf_eapol_keydes_key_iv, {
294 "Key IV", "eapol.keydes.key_iv", FT_BYTES, BASE_NONE,
295 NULL, 0x0, "Key Initialization Vector", HFILL }},
296 { &hf_eapol_keydes_key_index_keytype, {
297 "Key Type", "eapol.keydes.index.keytype", FT_BOOLEAN, 8,
298 TFS(&keytype_tfs), 0x80, "Key Type (unicast/broadcast)", HFILL }},
299 { &hf_eapol_keydes_key_index_indexnum, {
300 "Index Number", "eapol.keydes.index.indexnum", FT_UINT8, BASE_DEC,
301 NULL, 0x7F, "Key Index number", HFILL }},
302 { &hf_eapol_keydes_key_signature, {
303 "Key Signature", "eapol.keydes.key_signature", FT_BYTES, BASE_NONE,
304 NULL, 0x0, "Key Signature", HFILL }},
305 { &hf_eapol_keydes_key, {
306 "Key", "eapol.keydes.key", FT_BYTES, BASE_NONE,
307 NULL, 0x0, "Key", HFILL }},
309 { &hf_eapol_wpa_keydes_keyinfo, {
310 "Key Information", "eapol.keydes.key_info", FT_UINT16,
311 BASE_HEX, NULL, 0x0, "WPA key info", HFILL }},
313 { &hf_eapol_wpa_keydes_keyinfo_keydes_ver, {
314 "Key Descriptor Version",
315 "eapol.keydes.key_info.keydes_ver",
316 FT_UINT16, BASE_DEC, VALS(&keydes_ver),
317 KEY_INFO_KEYDES_VER_MASK,
318 "Key Descriptor Version Type", HFILL }},
319 { &hf_eapol_wpa_keydes_keyinfo_key_type, {
321 "eapol.keydes.key_info.key_type",
322 FT_BOOLEAN, 16, TFS(&tfs_keyinfo_key_type),
323 KEY_INFO_KEY_TYPE_MASK,
324 "Key Type (Pairwise or Group)", HFILL }},
325 { &hf_eapol_wpa_keydes_keyinfo_key_index, {
327 "eapol.keydes.key_info.key_index",
328 FT_UINT16, BASE_DEC, NULL,
329 KEY_INFO_KEY_INDEX_MASK,
330 "Key Index (0-3)", HFILL }},
331 { &hf_eapol_wpa_keydes_keyinfo_install, {
333 "eapol.keydes.key_info.install",
334 FT_BOOLEAN, 16, TFS(&flags_set_truth),
335 KEY_INFO_INSTALL_MASK,
336 "Install flag", HFILL }},
337 { &hf_eapol_wpa_keydes_keyinfo_key_ack, {
339 "eapol.keydes.key_info.key_ack",
340 FT_BOOLEAN, 16, TFS(&flags_set_truth),
341 KEY_INFO_KEY_ACK_MASK,
342 "Key Ack flag", HFILL }},
343 { &hf_eapol_wpa_keydes_keyinfo_key_mic, {
345 "eapol.keydes.key_info.key_mic",
346 FT_BOOLEAN, 16, TFS(&flags_set_truth),
347 KEY_INFO_KEY_MIC_MASK,
348 "Key MIC flag", HFILL }},
349 { &hf_eapol_wpa_keydes_keyinfo_secure, {
351 "eapol.keydes.key_info.secure",
352 FT_BOOLEAN, 16, TFS(&flags_set_truth),
353 KEY_INFO_SECURE_MASK,
354 "Secure flag", HFILL }},
355 { &hf_eapol_wpa_keydes_keyinfo_error, {
357 "eapol.keydes.key_info.error",
358 FT_BOOLEAN, 16, TFS(&flags_set_truth),
360 "Error flag", HFILL }},
361 { &hf_eapol_wpa_keydes_keyinfo_request, {
363 "eapol.keydes.key_info.request",
364 FT_BOOLEAN, 16, TFS(&flags_set_truth),
365 KEY_INFO_REQUEST_MASK,
366 "Request flag", HFILL }},
367 { &hf_eapol_wpa_keydes_nonce, {
368 "Nonce", "eapol.keydes.nonce", FT_BYTES, BASE_NONE,
369 NULL, 0x0, "WPA Key Nonce", HFILL }},
370 { &hf_eapol_wpa_keydes_rsc, {
371 "WPA Key RSC", "eapol.keydes.rsc", FT_BYTES, BASE_NONE, NULL,
372 0x0, "WPA Key Receive Sequence Counter", HFILL }},
373 { &hf_eapol_wpa_keydes_id, {
374 "WPA Key ID", "eapol.keydes.id", FT_BYTES, BASE_NONE, NULL,
375 0x0, "WPA Key ID", HFILL }},
376 { &hf_eapol_wpa_keydes_mic, {
377 "WPA Key MIC", "eapol.keydes.mic", FT_BYTES, BASE_NONE, NULL,
378 0x0, "WPA Key Message Integrity Check", HFILL }},
379 { &hf_eapol_wpa_keydes_datalen, {
380 "WPA Key Length", "eapol.keydes.datalen", FT_UINT16, BASE_DEC,
381 NULL, 0x0, "WPA Key Data Length", HFILL }},
382 { &hf_eapol_wpa_keydes_data, {
383 "WPA Key", "eapol.keydes.data", FT_BYTES, BASE_NONE,
384 NULL, 0x0, "WPA Key Data", HFILL }},
386 static gint *ett[] = {
388 &ett_eapol_keydes_data,
393 proto_eapol = proto_register_protocol("802.1x Authentication", "EAPOL", "eapol");
394 proto_register_field_array(proto_eapol, hf, array_length(hf));
395 proto_register_subtree_array(ett, array_length(ett));
399 proto_reg_handoff_eapol(void)
401 dissector_handle_t eapol_handle;
404 * Get handles for the EAP and raw data dissectors.
406 eap_handle = find_dissector("eap");
407 data_handle = find_dissector("data");
409 eapol_handle = create_dissector_handle(dissect_eapol, proto_eapol);
410 dissector_add("ethertype", ETHERTYPE_EAPOL, eapol_handle);