wpa_ie.c revision 33e38bfa7159cef089d6ee0d904778e184c72c47 
1/*
2 * wpa_supplicant - WPA/RSN IE and KDE processing
3 * Copyright (c) 2003-2008, Jouni Malinen <j@w1.fi>
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9#include "includes.h"
10
11#include "common.h"
12#include "wpa.h"
13#include "pmksa_cache.h"
14#include "common/ieee802_11_defs.h"
15#include "wpa_i.h"
16#include "wpa_ie.h"
17
18
19/**
20 * wpa_parse_wpa_ie - Parse WPA/RSN IE
21 * @wpa_ie: Pointer to WPA or RSN IE
22 * @wpa_ie_len: Length of the WPA/RSN IE
23 * @data: Pointer to data area for parsing results
24 * Returns: 0 on success, -1 on failure
25 *
26 * Parse the contents of WPA or RSN IE and write the parsed data into data.
27 */
28int wpa_parse_wpa_ie(const u8 *wpa_ie, size_t wpa_ie_len,
29		     struct wpa_ie_data *data)
30{
31	if (wpa_ie_len >= 1 && wpa_ie[0] == WLAN_EID_RSN)
32		return wpa_parse_wpa_ie_rsn(wpa_ie, wpa_ie_len, data);
33	else
34		return wpa_parse_wpa_ie_wpa(wpa_ie, wpa_ie_len, data);
35}
36
37
38static int wpa_gen_wpa_ie_wpa(u8 *wpa_ie, size_t wpa_ie_len,
39			      int pairwise_cipher, int group_cipher,
40			      int key_mgmt)
41{
42	u8 *pos;
43	struct wpa_ie_hdr *hdr;
44	u32 suite;
45
46	if (wpa_ie_len < sizeof(*hdr) + WPA_SELECTOR_LEN +
47	    2 + WPA_SELECTOR_LEN + 2 + WPA_SELECTOR_LEN)
48		return -1;
49
50	hdr = (struct wpa_ie_hdr *) wpa_ie;
51	hdr->elem_id = WLAN_EID_VENDOR_SPECIFIC;
52	RSN_SELECTOR_PUT(hdr->oui, WPA_OUI_TYPE);
53	WPA_PUT_LE16(hdr->version, WPA_VERSION);
54	pos = (u8 *) (hdr + 1);
55
56	suite = wpa_cipher_to_suite(WPA_PROTO_WPA, group_cipher);
57	if (suite == 0) {
58		wpa_printf(MSG_WARNING, "Invalid group cipher (%d).",
59			   group_cipher);
60		return -1;
61	}
62	RSN_SELECTOR_PUT(pos, suite);
63	pos += WPA_SELECTOR_LEN;
64
65	*pos++ = 1;
66	*pos++ = 0;
67	suite = wpa_cipher_to_suite(WPA_PROTO_WPA, pairwise_cipher);
68	if (suite == 0 ||
69	    (!wpa_cipher_valid_pairwise(pairwise_cipher) &&
70	     pairwise_cipher != WPA_CIPHER_NONE)) {
71		wpa_printf(MSG_WARNING, "Invalid pairwise cipher (%d).",
72			   pairwise_cipher);
73		return -1;
74	}
75	RSN_SELECTOR_PUT(pos, suite);
76	pos += WPA_SELECTOR_LEN;
77
78	*pos++ = 1;
79	*pos++ = 0;
80	if (key_mgmt == WPA_KEY_MGMT_IEEE8021X) {
81		RSN_SELECTOR_PUT(pos, WPA_AUTH_KEY_MGMT_UNSPEC_802_1X);
82	} else if (key_mgmt == WPA_KEY_MGMT_PSK) {
83		RSN_SELECTOR_PUT(pos, WPA_AUTH_KEY_MGMT_PSK_OVER_802_1X);
84	} else if (key_mgmt == WPA_KEY_MGMT_WPA_NONE) {
85		RSN_SELECTOR_PUT(pos, WPA_AUTH_KEY_MGMT_NONE);
86	} else if (key_mgmt == WPA_KEY_MGMT_CCKM) {
87		RSN_SELECTOR_PUT(pos, WPA_AUTH_KEY_MGMT_CCKM);
88	} else {
89		wpa_printf(MSG_WARNING, "Invalid key management type (%d).",
90			   key_mgmt);
91		return -1;
92	}
93	pos += WPA_SELECTOR_LEN;
94
95	/* WPA Capabilities; use defaults, so no need to include it */
96
97	hdr->len = (pos - wpa_ie) - 2;
98
99	WPA_ASSERT((size_t) (pos - wpa_ie) <= wpa_ie_len);
100
101	return pos - wpa_ie;
102}
103
104
105static int wpa_gen_wpa_ie_rsn(u8 *rsn_ie, size_t rsn_ie_len,
106			      int pairwise_cipher, int group_cipher,
107			      int key_mgmt, int mgmt_group_cipher,
108			      struct wpa_sm *sm)
109{
110#ifndef CONFIG_NO_WPA2
111	u8 *pos;
112	struct rsn_ie_hdr *hdr;
113	u16 capab;
114	u32 suite;
115
116	if (rsn_ie_len < sizeof(*hdr) + RSN_SELECTOR_LEN +
117	    2 + RSN_SELECTOR_LEN + 2 + RSN_SELECTOR_LEN + 2 +
118	    (sm->cur_pmksa ? 2 + PMKID_LEN : 0)) {
119		wpa_printf(MSG_DEBUG, "RSN: Too short IE buffer (%lu bytes)",
120			   (unsigned long) rsn_ie_len);
121		return -1;
122	}
123
124	hdr = (struct rsn_ie_hdr *) rsn_ie;
125	hdr->elem_id = WLAN_EID_RSN;
126	WPA_PUT_LE16(hdr->version, RSN_VERSION);
127	pos = (u8 *) (hdr + 1);
128
129	suite = wpa_cipher_to_suite(WPA_PROTO_RSN, group_cipher);
130	if (suite == 0) {
131		wpa_printf(MSG_WARNING, "Invalid group cipher (%d).",
132			   group_cipher);
133		return -1;
134	}
135	RSN_SELECTOR_PUT(pos, suite);
136	pos += RSN_SELECTOR_LEN;
137
138	*pos++ = 1;
139	*pos++ = 0;
140	suite = wpa_cipher_to_suite(WPA_PROTO_RSN, pairwise_cipher);
141	if (suite == 0 ||
142	    (!wpa_cipher_valid_pairwise(pairwise_cipher) &&
143	     pairwise_cipher != WPA_CIPHER_NONE)) {
144		wpa_printf(MSG_WARNING, "Invalid pairwise cipher (%d).",
145			   pairwise_cipher);
146		return -1;
147	}
148	RSN_SELECTOR_PUT(pos, suite);
149	pos += RSN_SELECTOR_LEN;
150
151	*pos++ = 1;
152	*pos++ = 0;
153	if (key_mgmt == WPA_KEY_MGMT_IEEE8021X) {
154		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_UNSPEC_802_1X);
155	} else if (key_mgmt == WPA_KEY_MGMT_PSK) {
156		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_PSK_OVER_802_1X);
157	} else if (key_mgmt == WPA_KEY_MGMT_CCKM) {
158		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_CCKM);
159#ifdef CONFIG_IEEE80211R
160	} else if (key_mgmt == WPA_KEY_MGMT_FT_IEEE8021X) {
161		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_802_1X);
162	} else if (key_mgmt == WPA_KEY_MGMT_FT_PSK) {
163		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_PSK);
164#endif /* CONFIG_IEEE80211R */
165#ifdef CONFIG_IEEE80211W
166	} else if (key_mgmt == WPA_KEY_MGMT_IEEE8021X_SHA256) {
167		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_802_1X_SHA256);
168	} else if (key_mgmt == WPA_KEY_MGMT_PSK_SHA256) {
169		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_PSK_SHA256);
170#endif /* CONFIG_IEEE80211W */
171#ifdef CONFIG_SAE
172	} else if (key_mgmt == WPA_KEY_MGMT_SAE) {
173		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_SAE);
174	} else if (key_mgmt == WPA_KEY_MGMT_FT_SAE) {
175		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_SAE);
176#endif /* CONFIG_SAE */
177	} else {
178		wpa_printf(MSG_WARNING, "Invalid key management type (%d).",
179			   key_mgmt);
180		return -1;
181	}
182	pos += RSN_SELECTOR_LEN;
183
184	/* RSN Capabilities */
185	capab = 0;
186#ifdef CONFIG_IEEE80211W
187	if (sm->mfp)
188		capab |= WPA_CAPABILITY_MFPC;
189	if (sm->mfp == 2)
190		capab |= WPA_CAPABILITY_MFPR;
191#endif /* CONFIG_IEEE80211W */
192	WPA_PUT_LE16(pos, capab);
193	pos += 2;
194
195	if (sm->cur_pmksa) {
196		/* PMKID Count (2 octets, little endian) */
197		*pos++ = 1;
198		*pos++ = 0;
199		/* PMKID */
200		os_memcpy(pos, sm->cur_pmksa->pmkid, PMKID_LEN);
201		pos += PMKID_LEN;
202	}
203
204#ifdef CONFIG_IEEE80211W
205	if (mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC) {
206		if (!sm->cur_pmksa) {
207			/* PMKID Count */
208			WPA_PUT_LE16(pos, 0);
209			pos += 2;
210		}
211
212		/* Management Group Cipher Suite */
213		RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_AES_128_CMAC);
214		pos += RSN_SELECTOR_LEN;
215	}
216#endif /* CONFIG_IEEE80211W */
217
218	hdr->len = (pos - rsn_ie) - 2;
219
220	WPA_ASSERT((size_t) (pos - rsn_ie) <= rsn_ie_len);
221
222	return pos - rsn_ie;
223#else /* CONFIG_NO_WPA2 */
224	return -1;
225#endif /* CONFIG_NO_WPA2 */
226}
227
228
229/**
230 * wpa_gen_wpa_ie - Generate WPA/RSN IE based on current security policy
231 * @sm: Pointer to WPA state machine data from wpa_sm_init()
232 * @wpa_ie: Pointer to memory area for the generated WPA/RSN IE
233 * @wpa_ie_len: Maximum length of the generated WPA/RSN IE
234 * Returns: Length of the generated WPA/RSN IE or -1 on failure
235 */
236int wpa_gen_wpa_ie(struct wpa_sm *sm, u8 *wpa_ie, size_t wpa_ie_len)
237{
238	if (sm->proto == WPA_PROTO_RSN)
239		return wpa_gen_wpa_ie_rsn(wpa_ie, wpa_ie_len,
240					  sm->pairwise_cipher,
241					  sm->group_cipher,
242					  sm->key_mgmt, sm->mgmt_group_cipher,
243					  sm);
244	else
245		return wpa_gen_wpa_ie_wpa(wpa_ie, wpa_ie_len,
246					  sm->pairwise_cipher,
247					  sm->group_cipher,
248					  sm->key_mgmt);
249}
250
251
252/**
253 * wpa_parse_generic - Parse EAPOL-Key Key Data Generic IEs
254 * @pos: Pointer to the IE header
255 * @end: Pointer to the end of the Key Data buffer
256 * @ie: Pointer to parsed IE data
257 * Returns: 0 on success, 1 if end mark is found, -1 on failure
258 */
259static int wpa_parse_generic(const u8 *pos, const u8 *end,
260			     struct wpa_eapol_ie_parse *ie)
261{
262	if (pos[1] == 0)
263		return 1;
264
265	if (pos[1] >= 6 &&
266	    RSN_SELECTOR_GET(pos + 2) == WPA_OUI_TYPE &&
267	    pos[2 + WPA_SELECTOR_LEN] == 1 &&
268	    pos[2 + WPA_SELECTOR_LEN + 1] == 0) {
269		ie->wpa_ie = pos;
270		ie->wpa_ie_len = pos[1] + 2;
271		wpa_hexdump(MSG_DEBUG, "WPA: WPA IE in EAPOL-Key",
272			    ie->wpa_ie, ie->wpa_ie_len);
273		return 0;
274	}
275
276	if (pos + 1 + RSN_SELECTOR_LEN < end &&
277	    pos[1] >= RSN_SELECTOR_LEN + PMKID_LEN &&
278	    RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_PMKID) {
279		ie->pmkid = pos + 2 + RSN_SELECTOR_LEN;
280		wpa_hexdump(MSG_DEBUG, "WPA: PMKID in EAPOL-Key",
281			    pos, pos[1] + 2);
282		return 0;
283	}
284
285	if (pos[1] > RSN_SELECTOR_LEN + 2 &&
286	    RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_GROUPKEY) {
287		ie->gtk = pos + 2 + RSN_SELECTOR_LEN;
288		ie->gtk_len = pos[1] - RSN_SELECTOR_LEN;
289		wpa_hexdump_key(MSG_DEBUG, "WPA: GTK in EAPOL-Key",
290				pos, pos[1] + 2);
291		return 0;
292	}
293
294	if (pos[1] > RSN_SELECTOR_LEN + 2 &&
295	    RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_MAC_ADDR) {
296		ie->mac_addr = pos + 2 + RSN_SELECTOR_LEN;
297		ie->mac_addr_len = pos[1] - RSN_SELECTOR_LEN;
298		wpa_hexdump(MSG_DEBUG, "WPA: MAC Address in EAPOL-Key",
299			    pos, pos[1] + 2);
300		return 0;
301	}
302
303#ifdef CONFIG_PEERKEY
304	if (pos[1] > RSN_SELECTOR_LEN + 2 &&
305	    RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_SMK) {
306		ie->smk = pos + 2 + RSN_SELECTOR_LEN;
307		ie->smk_len = pos[1] - RSN_SELECTOR_LEN;
308		wpa_hexdump_key(MSG_DEBUG, "WPA: SMK in EAPOL-Key",
309				pos, pos[1] + 2);
310		return 0;
311	}
312
313	if (pos[1] > RSN_SELECTOR_LEN + 2 &&
314	    RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_NONCE) {
315		ie->nonce = pos + 2 + RSN_SELECTOR_LEN;
316		ie->nonce_len = pos[1] - RSN_SELECTOR_LEN;
317		wpa_hexdump(MSG_DEBUG, "WPA: Nonce in EAPOL-Key",
318			    pos, pos[1] + 2);
319		return 0;
320	}
321
322	if (pos[1] > RSN_SELECTOR_LEN + 2 &&
323	    RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_LIFETIME) {
324		ie->lifetime = pos + 2 + RSN_SELECTOR_LEN;
325		ie->lifetime_len = pos[1] - RSN_SELECTOR_LEN;
326		wpa_hexdump(MSG_DEBUG, "WPA: Lifetime in EAPOL-Key",
327			    pos, pos[1] + 2);
328		return 0;
329	}
330
331	if (pos[1] > RSN_SELECTOR_LEN + 2 &&
332	    RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_ERROR) {
333		ie->error = pos + 2 + RSN_SELECTOR_LEN;
334		ie->error_len = pos[1] - RSN_SELECTOR_LEN;
335		wpa_hexdump(MSG_DEBUG, "WPA: Error in EAPOL-Key",
336			    pos, pos[1] + 2);
337		return 0;
338	}
339#endif /* CONFIG_PEERKEY */
340
341#ifdef CONFIG_IEEE80211W
342	if (pos[1] > RSN_SELECTOR_LEN + 2 &&
343	    RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_IGTK) {
344		ie->igtk = pos + 2 + RSN_SELECTOR_LEN;
345		ie->igtk_len = pos[1] - RSN_SELECTOR_LEN;
346		wpa_hexdump_key(MSG_DEBUG, "WPA: IGTK in EAPOL-Key",
347				pos, pos[1] + 2);
348		return 0;
349	}
350#endif /* CONFIG_IEEE80211W */
351
352	return 0;
353}
354
355
356/**
357 * wpa_supplicant_parse_ies - Parse EAPOL-Key Key Data IEs
358 * @buf: Pointer to the Key Data buffer
359 * @len: Key Data Length
360 * @ie: Pointer to parsed IE data
361 * Returns: 0 on success, -1 on failure
362 */
363int wpa_supplicant_parse_ies(const u8 *buf, size_t len,
364			     struct wpa_eapol_ie_parse *ie)
365{
366	const u8 *pos, *end;
367	int ret = 0;
368
369	os_memset(ie, 0, sizeof(*ie));
370	for (pos = buf, end = pos + len; pos + 1 < end; pos += 2 + pos[1]) {
371		if (pos[0] == 0xdd &&
372		    ((pos == buf + len - 1) || pos[1] == 0)) {
373			/* Ignore padding */
374			break;
375		}
376		if (pos + 2 + pos[1] > end) {
377			wpa_printf(MSG_DEBUG, "WPA: EAPOL-Key Key Data "
378				   "underflow (ie=%d len=%d pos=%d)",
379				   pos[0], pos[1], (int) (pos - buf));
380			wpa_hexdump_key(MSG_DEBUG, "WPA: Key Data",
381					buf, len);
382			ret = -1;
383			break;
384		}
385		if (*pos == WLAN_EID_RSN) {
386			ie->rsn_ie = pos;
387			ie->rsn_ie_len = pos[1] + 2;
388			wpa_hexdump(MSG_DEBUG, "WPA: RSN IE in EAPOL-Key",
389				    ie->rsn_ie, ie->rsn_ie_len);
390		} else if (*pos == WLAN_EID_MOBILITY_DOMAIN) {
391			ie->mdie = pos;
392			ie->mdie_len = pos[1] + 2;
393			wpa_hexdump(MSG_DEBUG, "WPA: MDIE in EAPOL-Key",
394				    ie->mdie, ie->mdie_len);
395		} else if (*pos == WLAN_EID_FAST_BSS_TRANSITION) {
396			ie->ftie = pos;
397			ie->ftie_len = pos[1] + 2;
398			wpa_hexdump(MSG_DEBUG, "WPA: FTIE in EAPOL-Key",
399				    ie->ftie, ie->ftie_len);
400		} else if (*pos == WLAN_EID_TIMEOUT_INTERVAL && pos[1] >= 5) {
401			if (pos[2] == WLAN_TIMEOUT_REASSOC_DEADLINE) {
402				ie->reassoc_deadline = pos;
403				wpa_hexdump(MSG_DEBUG, "WPA: Reassoc Deadline "
404					    "in EAPOL-Key",
405					    ie->reassoc_deadline, pos[1] + 2);
406			} else if (pos[2] == WLAN_TIMEOUT_KEY_LIFETIME) {
407				ie->key_lifetime = pos;
408				wpa_hexdump(MSG_DEBUG, "WPA: KeyLifetime "
409					    "in EAPOL-Key",
410					    ie->key_lifetime, pos[1] + 2);
411			} else {
412				wpa_hexdump(MSG_DEBUG, "WPA: Unrecognized "
413					    "EAPOL-Key Key Data IE",
414					    pos, 2 + pos[1]);
415			}
416		} else if (*pos == WLAN_EID_LINK_ID) {
417			if (pos[1] >= 18) {
418				ie->lnkid = pos;
419				ie->lnkid_len = pos[1] + 2;
420			}
421		} else if (*pos == WLAN_EID_EXT_CAPAB) {
422			ie->ext_capab = pos;
423			ie->ext_capab_len = pos[1] + 2;
424		} else if (*pos == WLAN_EID_SUPP_RATES) {
425			ie->supp_rates = pos;
426			ie->supp_rates_len = pos[1] + 2;
427		} else if (*pos == WLAN_EID_EXT_SUPP_RATES) {
428			ie->ext_supp_rates = pos;
429			ie->ext_supp_rates_len = pos[1] + 2;
430		} else if (*pos == WLAN_EID_HT_CAP) {
431			ie->ht_capabilities = pos + 2;
432			ie->ht_capabilities_len = pos[1];
433		} else if (*pos == WLAN_EID_VHT_CAP) {
434			ie->vht_capabilities = pos + 2;
435			ie->vht_capabilities_len = pos[1];
436		} else if (*pos == WLAN_EID_QOS && pos[1] >= 1) {
437			ie->qosinfo = pos[2];
438		} else if (*pos == WLAN_EID_VENDOR_SPECIFIC) {
439			ret = wpa_parse_generic(pos, end, ie);
440			if (ret < 0)
441				break;
442			if (ret > 0) {
443				ret = 0;
444				break;
445			}
446		} else {
447			wpa_hexdump(MSG_DEBUG, "WPA: Unrecognized EAPOL-Key "
448				    "Key Data IE", pos, 2 + pos[1]);
449		}
450	}
451
452	return ret;
453}
454