1/*
2 * WPA Supplicant - IEEE 802.11r - Fast BSS Transition
3 * Copyright (c) 2006-2007, 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 "crypto/aes_wrap.h"
13#include "crypto/random.h"
14#include "common/ieee802_11_defs.h"
15#include "common/ieee802_11_common.h"
16#include "wpa.h"
17#include "wpa_i.h"
18
19#ifdef CONFIG_IEEE80211R
20
21int wpa_derive_ptk_ft(struct wpa_sm *sm, const unsigned char *src_addr,
22		      const struct wpa_eapol_key *key,
23		      struct wpa_ptk *ptk, size_t ptk_len)
24{
25	u8 ptk_name[WPA_PMK_NAME_LEN];
26	const u8 *anonce = key->key_nonce;
27
28	if (sm->xxkey_len == 0) {
29		wpa_printf(MSG_DEBUG, "FT: XXKey not available for key "
30			   "derivation");
31		return -1;
32	}
33
34	wpa_derive_pmk_r0(sm->xxkey, sm->xxkey_len, sm->ssid,
35			  sm->ssid_len, sm->mobility_domain,
36			  sm->r0kh_id, sm->r0kh_id_len, sm->own_addr,
37			  sm->pmk_r0, sm->pmk_r0_name);
38	wpa_hexdump_key(MSG_DEBUG, "FT: PMK-R0", sm->pmk_r0, PMK_LEN);
39	wpa_hexdump(MSG_DEBUG, "FT: PMKR0Name",
40		    sm->pmk_r0_name, WPA_PMK_NAME_LEN);
41	wpa_derive_pmk_r1(sm->pmk_r0, sm->pmk_r0_name, sm->r1kh_id,
42			  sm->own_addr, sm->pmk_r1, sm->pmk_r1_name);
43	wpa_hexdump_key(MSG_DEBUG, "FT: PMK-R1", sm->pmk_r1, PMK_LEN);
44	wpa_hexdump(MSG_DEBUG, "FT: PMKR1Name", sm->pmk_r1_name,
45		    WPA_PMK_NAME_LEN);
46	wpa_pmk_r1_to_ptk(sm->pmk_r1, sm->snonce, anonce, sm->own_addr,
47			  sm->bssid, sm->pmk_r1_name,
48			  (u8 *) ptk, ptk_len, ptk_name);
49	wpa_hexdump_key(MSG_DEBUG, "FT: PTK", (u8 *) ptk, ptk_len);
50	wpa_hexdump(MSG_DEBUG, "FT: PTKName", ptk_name, WPA_PMK_NAME_LEN);
51
52	return 0;
53}
54
55
56/**
57 * wpa_sm_set_ft_params - Set FT (IEEE 802.11r) parameters
58 * @sm: Pointer to WPA state machine data from wpa_sm_init()
59 * @ies: Association Response IEs or %NULL to clear FT parameters
60 * @ies_len: Length of ies buffer in octets
61 * Returns: 0 on success, -1 on failure
62 */
63int wpa_sm_set_ft_params(struct wpa_sm *sm, const u8 *ies, size_t ies_len)
64{
65	struct wpa_ft_ies ft;
66
67	if (sm == NULL)
68		return 0;
69
70	if (wpa_ft_parse_ies(ies, ies_len, &ft) < 0)
71		return -1;
72
73	if (ft.mdie && ft.mdie_len < MOBILITY_DOMAIN_ID_LEN + 1)
74		return -1;
75
76	if (ft.mdie) {
77		wpa_hexdump(MSG_DEBUG, "FT: Mobility domain",
78			    ft.mdie, MOBILITY_DOMAIN_ID_LEN);
79		os_memcpy(sm->mobility_domain, ft.mdie,
80			  MOBILITY_DOMAIN_ID_LEN);
81		sm->mdie_ft_capab = ft.mdie[MOBILITY_DOMAIN_ID_LEN];
82		wpa_printf(MSG_DEBUG, "FT: Capability and Policy: 0x%02x",
83			   sm->mdie_ft_capab);
84	} else
85		os_memset(sm->mobility_domain, 0, MOBILITY_DOMAIN_ID_LEN);
86
87	if (ft.r0kh_id) {
88		wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID",
89			    ft.r0kh_id, ft.r0kh_id_len);
90		os_memcpy(sm->r0kh_id, ft.r0kh_id, ft.r0kh_id_len);
91		sm->r0kh_id_len = ft.r0kh_id_len;
92	} else {
93		/* FIX: When should R0KH-ID be cleared? We need to keep the
94		 * old R0KH-ID in order to be able to use this during FT. */
95		/*
96		 * os_memset(sm->r0kh_id, 0, FT_R0KH_ID_LEN);
97		 * sm->r0kh_id_len = 0;
98		 */
99	}
100
101	if (ft.r1kh_id) {
102		wpa_hexdump(MSG_DEBUG, "FT: R1KH-ID",
103			    ft.r1kh_id, FT_R1KH_ID_LEN);
104		os_memcpy(sm->r1kh_id, ft.r1kh_id, FT_R1KH_ID_LEN);
105	} else
106		os_memset(sm->r1kh_id, 0, FT_R1KH_ID_LEN);
107
108	os_free(sm->assoc_resp_ies);
109	sm->assoc_resp_ies = os_malloc(ft.mdie_len + 2 + ft.ftie_len + 2);
110	if (sm->assoc_resp_ies) {
111		u8 *pos = sm->assoc_resp_ies;
112		if (ft.mdie) {
113			os_memcpy(pos, ft.mdie - 2, ft.mdie_len + 2);
114			pos += ft.mdie_len + 2;
115		}
116		if (ft.ftie) {
117			os_memcpy(pos, ft.ftie - 2, ft.ftie_len + 2);
118			pos += ft.ftie_len + 2;
119		}
120		sm->assoc_resp_ies_len = pos - sm->assoc_resp_ies;
121		wpa_hexdump(MSG_DEBUG, "FT: Stored MDIE and FTIE from "
122			    "(Re)Association Response",
123			    sm->assoc_resp_ies, sm->assoc_resp_ies_len);
124	}
125
126	return 0;
127}
128
129
130/**
131 * wpa_ft_gen_req_ies - Generate FT (IEEE 802.11r) IEs for Auth/ReAssoc Request
132 * @sm: Pointer to WPA state machine data from wpa_sm_init()
133 * @len: Buffer for returning the length of the IEs
134 * @anonce: ANonce or %NULL if not yet available
135 * @pmk_name: PMKR0Name or PMKR1Name to be added into the RSN IE PMKID List
136 * @kck: 128-bit KCK for MIC or %NULL if no MIC is used
137 * @target_ap: Target AP address
138 * @ric_ies: Optional IE(s), e.g., WMM TSPEC(s), for RIC-Request or %NULL
139 * @ric_ies_len: Length of ric_ies buffer in octets
140 * @ap_mdie: Mobility Domain IE from the target AP
141 * Returns: Pointer to buffer with IEs or %NULL on failure
142 *
143 * Caller is responsible for freeing the returned buffer with os_free();
144 */
145static u8 * wpa_ft_gen_req_ies(struct wpa_sm *sm, size_t *len,
146			       const u8 *anonce, const u8 *pmk_name,
147			       const u8 *kck, const u8 *target_ap,
148			       const u8 *ric_ies, size_t ric_ies_len,
149			       const u8 *ap_mdie)
150{
151	size_t buf_len;
152	u8 *buf, *pos, *ftie_len, *ftie_pos;
153	struct rsn_mdie *mdie;
154	struct rsn_ftie *ftie;
155	struct rsn_ie_hdr *rsnie;
156	u16 capab;
157
158	sm->ft_completed = 0;
159
160	buf_len = 2 + sizeof(struct rsn_mdie) + 2 + sizeof(struct rsn_ftie) +
161		2 + sm->r0kh_id_len + ric_ies_len + 100;
162	buf = os_zalloc(buf_len);
163	if (buf == NULL)
164		return NULL;
165	pos = buf;
166
167	/* RSNIE[PMKR0Name/PMKR1Name] */
168	rsnie = (struct rsn_ie_hdr *) pos;
169	rsnie->elem_id = WLAN_EID_RSN;
170	WPA_PUT_LE16(rsnie->version, RSN_VERSION);
171	pos = (u8 *) (rsnie + 1);
172
173	/* Group Suite Selector */
174	if (sm->group_cipher != WPA_CIPHER_CCMP &&
175	    sm->group_cipher != WPA_CIPHER_GCMP &&
176	    sm->group_cipher != WPA_CIPHER_TKIP) {
177		wpa_printf(MSG_WARNING, "FT: Invalid group cipher (%d)",
178			   sm->group_cipher);
179		os_free(buf);
180		return NULL;
181	}
182	RSN_SELECTOR_PUT(pos, wpa_cipher_to_suite(WPA_PROTO_RSN,
183						  sm->group_cipher));
184	pos += RSN_SELECTOR_LEN;
185
186	/* Pairwise Suite Count */
187	WPA_PUT_LE16(pos, 1);
188	pos += 2;
189
190	/* Pairwise Suite List */
191	if (!wpa_cipher_valid_pairwise(sm->pairwise_cipher)) {
192		wpa_printf(MSG_WARNING, "FT: Invalid pairwise cipher (%d)",
193			   sm->pairwise_cipher);
194		os_free(buf);
195		return NULL;
196	}
197	RSN_SELECTOR_PUT(pos, wpa_cipher_to_suite(WPA_PROTO_RSN,
198						  sm->pairwise_cipher));
199	pos += RSN_SELECTOR_LEN;
200
201	/* Authenticated Key Management Suite Count */
202	WPA_PUT_LE16(pos, 1);
203	pos += 2;
204
205	/* Authenticated Key Management Suite List */
206	if (sm->key_mgmt == WPA_KEY_MGMT_FT_IEEE8021X)
207		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_802_1X);
208	else if (sm->key_mgmt == WPA_KEY_MGMT_FT_PSK)
209		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_PSK);
210	else if (sm->key_mgmt == WPA_KEY_MGMT_FT_SAE)
211		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_SAE);
212	else {
213		wpa_printf(MSG_WARNING, "FT: Invalid key management type (%d)",
214			   sm->key_mgmt);
215		os_free(buf);
216		return NULL;
217	}
218	pos += RSN_SELECTOR_LEN;
219
220	/* RSN Capabilities */
221	capab = 0;
222#ifdef CONFIG_IEEE80211W
223	if (sm->mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC)
224		capab |= WPA_CAPABILITY_MFPC;
225#endif /* CONFIG_IEEE80211W */
226	WPA_PUT_LE16(pos, capab);
227	pos += 2;
228
229	/* PMKID Count */
230	WPA_PUT_LE16(pos, 1);
231	pos += 2;
232
233	/* PMKID List [PMKR0Name/PMKR1Name] */
234	os_memcpy(pos, pmk_name, WPA_PMK_NAME_LEN);
235	pos += WPA_PMK_NAME_LEN;
236
237#ifdef CONFIG_IEEE80211W
238	if (sm->mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC) {
239		/* Management Group Cipher Suite */
240		RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_AES_128_CMAC);
241		pos += RSN_SELECTOR_LEN;
242	}
243#endif /* CONFIG_IEEE80211W */
244
245	rsnie->len = (pos - (u8 *) rsnie) - 2;
246
247	/* MDIE */
248	*pos++ = WLAN_EID_MOBILITY_DOMAIN;
249	*pos++ = sizeof(*mdie);
250	mdie = (struct rsn_mdie *) pos;
251	pos += sizeof(*mdie);
252	os_memcpy(mdie->mobility_domain, sm->mobility_domain,
253		  MOBILITY_DOMAIN_ID_LEN);
254	mdie->ft_capab = ap_mdie && ap_mdie[1] >= 3 ? ap_mdie[4] :
255		sm->mdie_ft_capab;
256
257	/* FTIE[SNonce, [R1KH-ID,] R0KH-ID ] */
258	ftie_pos = pos;
259	*pos++ = WLAN_EID_FAST_BSS_TRANSITION;
260	ftie_len = pos++;
261	ftie = (struct rsn_ftie *) pos;
262	pos += sizeof(*ftie);
263	os_memcpy(ftie->snonce, sm->snonce, WPA_NONCE_LEN);
264	if (anonce)
265		os_memcpy(ftie->anonce, anonce, WPA_NONCE_LEN);
266	if (kck) {
267		/* R1KH-ID sub-element in third FT message */
268		*pos++ = FTIE_SUBELEM_R1KH_ID;
269		*pos++ = FT_R1KH_ID_LEN;
270		os_memcpy(pos, sm->r1kh_id, FT_R1KH_ID_LEN);
271		pos += FT_R1KH_ID_LEN;
272	}
273	/* R0KH-ID sub-element */
274	*pos++ = FTIE_SUBELEM_R0KH_ID;
275	*pos++ = sm->r0kh_id_len;
276	os_memcpy(pos, sm->r0kh_id, sm->r0kh_id_len);
277	pos += sm->r0kh_id_len;
278	*ftie_len = pos - ftie_len - 1;
279
280	if (ric_ies) {
281		/* RIC Request */
282		os_memcpy(pos, ric_ies, ric_ies_len);
283		pos += ric_ies_len;
284	}
285
286	if (kck) {
287		/*
288		 * IEEE Std 802.11r-2008, 11A.8.4
289		 * MIC shall be calculated over:
290		 * non-AP STA MAC address
291		 * Target AP MAC address
292		 * Transaction seq number (5 for ReassocReq, 3 otherwise)
293		 * RSN IE
294		 * MDIE
295		 * FTIE (with MIC field set to 0)
296		 * RIC-Request (if present)
297		 */
298		/* Information element count */
299		ftie->mic_control[1] = 3 + ieee802_11_ie_count(ric_ies,
300							       ric_ies_len);
301		if (wpa_ft_mic(kck, sm->own_addr, target_ap, 5,
302			       ((u8 *) mdie) - 2, 2 + sizeof(*mdie),
303			       ftie_pos, 2 + *ftie_len,
304			       (u8 *) rsnie, 2 + rsnie->len, ric_ies,
305			       ric_ies_len, ftie->mic) < 0) {
306			wpa_printf(MSG_INFO, "FT: Failed to calculate MIC");
307			os_free(buf);
308			return NULL;
309		}
310	}
311
312	*len = pos - buf;
313
314	return buf;
315}
316
317
318static int wpa_ft_install_ptk(struct wpa_sm *sm, const u8 *bssid)
319{
320	int keylen;
321	enum wpa_alg alg;
322	u8 null_rsc[6] = { 0, 0, 0, 0, 0, 0 };
323
324	wpa_printf(MSG_DEBUG, "FT: Installing PTK to the driver.");
325
326	if (!wpa_cipher_valid_pairwise(sm->pairwise_cipher)) {
327		wpa_printf(MSG_WARNING, "FT: Unsupported pairwise cipher %d",
328			   sm->pairwise_cipher);
329		return -1;
330	}
331
332	alg = wpa_cipher_to_alg(sm->pairwise_cipher);
333	keylen = wpa_cipher_key_len(sm->pairwise_cipher);
334
335	if (wpa_sm_set_key(sm, alg, bssid, 0, 1, null_rsc,
336			   sizeof(null_rsc), (u8 *) sm->ptk.tk1, keylen) < 0) {
337		wpa_printf(MSG_WARNING, "FT: Failed to set PTK to the driver");
338		return -1;
339	}
340
341	return 0;
342}
343
344
345/**
346 * wpa_ft_prepare_auth_request - Generate over-the-air auth request
347 * @sm: Pointer to WPA state machine data from wpa_sm_init()
348 * @mdie: Target AP MDIE
349 * Returns: 0 on success, -1 on failure
350 */
351int wpa_ft_prepare_auth_request(struct wpa_sm *sm, const u8 *mdie)
352{
353	u8 *ft_ies;
354	size_t ft_ies_len;
355
356	/* Generate a new SNonce */
357	if (random_get_bytes(sm->snonce, WPA_NONCE_LEN)) {
358		wpa_printf(MSG_INFO, "FT: Failed to generate a new SNonce");
359		return -1;
360	}
361
362	ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, NULL, sm->pmk_r0_name,
363				    NULL, sm->bssid, NULL, 0, mdie);
364	if (ft_ies) {
365		wpa_sm_update_ft_ies(sm, sm->mobility_domain,
366				     ft_ies, ft_ies_len);
367		os_free(ft_ies);
368	}
369
370	return 0;
371}
372
373
374int wpa_ft_process_response(struct wpa_sm *sm, const u8 *ies, size_t ies_len,
375			    int ft_action, const u8 *target_ap,
376			    const u8 *ric_ies, size_t ric_ies_len)
377{
378	u8 *ft_ies;
379	size_t ft_ies_len, ptk_len;
380	struct wpa_ft_ies parse;
381	struct rsn_mdie *mdie;
382	struct rsn_ftie *ftie;
383	u8 ptk_name[WPA_PMK_NAME_LEN];
384	int ret;
385	const u8 *bssid;
386
387	wpa_hexdump(MSG_DEBUG, "FT: Response IEs", ies, ies_len);
388	wpa_hexdump(MSG_DEBUG, "FT: RIC IEs", ric_ies, ric_ies_len);
389
390	if (ft_action) {
391		if (!sm->over_the_ds_in_progress) {
392			wpa_printf(MSG_DEBUG, "FT: No over-the-DS in progress "
393				   "- drop FT Action Response");
394			return -1;
395		}
396
397		if (os_memcmp(target_ap, sm->target_ap, ETH_ALEN) != 0) {
398			wpa_printf(MSG_DEBUG, "FT: No over-the-DS in progress "
399				   "with this Target AP - drop FT Action "
400				   "Response");
401			return -1;
402		}
403	}
404
405	if (!wpa_key_mgmt_ft(sm->key_mgmt)) {
406		wpa_printf(MSG_DEBUG, "FT: Reject FT IEs since FT is not "
407			   "enabled for this connection");
408		return -1;
409	}
410
411	if (wpa_ft_parse_ies(ies, ies_len, &parse) < 0) {
412		wpa_printf(MSG_DEBUG, "FT: Failed to parse IEs");
413		return -1;
414	}
415
416	mdie = (struct rsn_mdie *) parse.mdie;
417	if (mdie == NULL || parse.mdie_len < sizeof(*mdie) ||
418	    os_memcmp(mdie->mobility_domain, sm->mobility_domain,
419		      MOBILITY_DOMAIN_ID_LEN) != 0) {
420		wpa_printf(MSG_DEBUG, "FT: Invalid MDIE");
421		return -1;
422	}
423
424	ftie = (struct rsn_ftie *) parse.ftie;
425	if (ftie == NULL || parse.ftie_len < sizeof(*ftie)) {
426		wpa_printf(MSG_DEBUG, "FT: Invalid FTIE");
427		return -1;
428	}
429
430	if (os_memcmp(ftie->snonce, sm->snonce, WPA_NONCE_LEN) != 0) {
431		wpa_printf(MSG_DEBUG, "FT: SNonce mismatch in FTIE");
432		wpa_hexdump(MSG_DEBUG, "FT: Received SNonce",
433			    ftie->snonce, WPA_NONCE_LEN);
434		wpa_hexdump(MSG_DEBUG, "FT: Expected SNonce",
435			    sm->snonce, WPA_NONCE_LEN);
436		return -1;
437	}
438
439	if (parse.r0kh_id == NULL) {
440		wpa_printf(MSG_DEBUG, "FT: No R0KH-ID subelem in FTIE");
441		return -1;
442	}
443
444	if (parse.r0kh_id_len != sm->r0kh_id_len ||
445	    os_memcmp_const(parse.r0kh_id, sm->r0kh_id, parse.r0kh_id_len) != 0)
446	{
447		wpa_printf(MSG_DEBUG, "FT: R0KH-ID in FTIE did not match with "
448			   "the current R0KH-ID");
449		wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID in FTIE",
450			    parse.r0kh_id, parse.r0kh_id_len);
451		wpa_hexdump(MSG_DEBUG, "FT: The current R0KH-ID",
452			    sm->r0kh_id, sm->r0kh_id_len);
453		return -1;
454	}
455
456	if (parse.r1kh_id == NULL) {
457		wpa_printf(MSG_DEBUG, "FT: No R1KH-ID subelem in FTIE");
458		return -1;
459	}
460
461	if (parse.rsn_pmkid == NULL ||
462	    os_memcmp_const(parse.rsn_pmkid, sm->pmk_r0_name, WPA_PMK_NAME_LEN))
463	{
464		wpa_printf(MSG_DEBUG, "FT: No matching PMKR0Name (PMKID) in "
465			   "RSNIE");
466		return -1;
467	}
468
469	os_memcpy(sm->r1kh_id, parse.r1kh_id, FT_R1KH_ID_LEN);
470	wpa_hexdump(MSG_DEBUG, "FT: R1KH-ID", sm->r1kh_id, FT_R1KH_ID_LEN);
471	wpa_hexdump(MSG_DEBUG, "FT: SNonce", sm->snonce, WPA_NONCE_LEN);
472	wpa_hexdump(MSG_DEBUG, "FT: ANonce", ftie->anonce, WPA_NONCE_LEN);
473	os_memcpy(sm->anonce, ftie->anonce, WPA_NONCE_LEN);
474	wpa_derive_pmk_r1(sm->pmk_r0, sm->pmk_r0_name, sm->r1kh_id,
475			  sm->own_addr, sm->pmk_r1, sm->pmk_r1_name);
476	wpa_hexdump_key(MSG_DEBUG, "FT: PMK-R1", sm->pmk_r1, PMK_LEN);
477	wpa_hexdump(MSG_DEBUG, "FT: PMKR1Name",
478		    sm->pmk_r1_name, WPA_PMK_NAME_LEN);
479
480	bssid = target_ap;
481	ptk_len = sm->pairwise_cipher != WPA_CIPHER_TKIP ? 48 : 64;
482	wpa_pmk_r1_to_ptk(sm->pmk_r1, sm->snonce, ftie->anonce, sm->own_addr,
483			  bssid, sm->pmk_r1_name,
484			  (u8 *) &sm->ptk, ptk_len, ptk_name);
485	wpa_hexdump_key(MSG_DEBUG, "FT: PTK",
486			(u8 *) &sm->ptk, ptk_len);
487	wpa_hexdump(MSG_DEBUG, "FT: PTKName", ptk_name, WPA_PMK_NAME_LEN);
488
489	ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, ftie->anonce,
490				    sm->pmk_r1_name, sm->ptk.kck, bssid,
491				    ric_ies, ric_ies_len,
492				    parse.mdie ? parse.mdie - 2 : NULL);
493	if (ft_ies) {
494		wpa_sm_update_ft_ies(sm, sm->mobility_domain,
495				     ft_ies, ft_ies_len);
496		os_free(ft_ies);
497	}
498
499	wpa_sm_mark_authenticated(sm, bssid);
500	ret = wpa_ft_install_ptk(sm, bssid);
501	if (ret) {
502		/*
503		 * Some drivers do not support key configuration when we are
504		 * not associated with the target AP. Work around this by
505		 * trying again after the following reassociation gets
506		 * completed.
507		 */
508		wpa_printf(MSG_DEBUG, "FT: Failed to set PTK prior to "
509			   "association - try again after reassociation");
510		sm->set_ptk_after_assoc = 1;
511	} else
512		sm->set_ptk_after_assoc = 0;
513
514	sm->ft_completed = 1;
515	if (ft_action) {
516		/*
517		 * The caller is expected trigger re-association with the
518		 * Target AP.
519		 */
520		os_memcpy(sm->bssid, target_ap, ETH_ALEN);
521	}
522
523	return 0;
524}
525
526
527int wpa_ft_is_completed(struct wpa_sm *sm)
528{
529	if (sm == NULL)
530		return 0;
531
532	if (!wpa_key_mgmt_ft(sm->key_mgmt))
533		return 0;
534
535	return sm->ft_completed;
536}
537
538
539void wpa_reset_ft_completed(struct wpa_sm *sm)
540{
541	if (sm != NULL)
542		sm->ft_completed = 0;
543}
544
545
546static int wpa_ft_process_gtk_subelem(struct wpa_sm *sm, const u8 *gtk_elem,
547				      size_t gtk_elem_len)
548{
549	u8 gtk[32];
550	int keyidx;
551	enum wpa_alg alg;
552	size_t gtk_len, keylen, rsc_len;
553
554	if (gtk_elem == NULL) {
555		wpa_printf(MSG_DEBUG, "FT: No GTK included in FTIE");
556		return 0;
557	}
558
559	wpa_hexdump_key(MSG_DEBUG, "FT: Received GTK in Reassoc Resp",
560			gtk_elem, gtk_elem_len);
561
562	if (gtk_elem_len < 11 + 24 || (gtk_elem_len - 11) % 8 ||
563	    gtk_elem_len - 19 > sizeof(gtk)) {
564		wpa_printf(MSG_DEBUG, "FT: Invalid GTK sub-elem "
565			   "length %lu", (unsigned long) gtk_elem_len);
566		return -1;
567	}
568	gtk_len = gtk_elem_len - 19;
569	if (aes_unwrap(sm->ptk.kek, 16, gtk_len / 8, gtk_elem + 11, gtk)) {
570		wpa_printf(MSG_WARNING, "FT: AES unwrap failed - could not "
571			   "decrypt GTK");
572		return -1;
573	}
574
575	keylen = wpa_cipher_key_len(sm->group_cipher);
576	rsc_len = wpa_cipher_rsc_len(sm->group_cipher);
577	alg = wpa_cipher_to_alg(sm->group_cipher);
578	if (alg == WPA_ALG_NONE) {
579		wpa_printf(MSG_WARNING, "WPA: Unsupported Group Cipher %d",
580			   sm->group_cipher);
581		return -1;
582	}
583
584	if (gtk_len < keylen) {
585		wpa_printf(MSG_DEBUG, "FT: Too short GTK in FTIE");
586		return -1;
587	}
588
589	/* Key Info[2] | Key Length[1] | RSC[8] | Key[5..32]. */
590
591	keyidx = WPA_GET_LE16(gtk_elem) & 0x03;
592
593	if (gtk_elem[2] != keylen) {
594		wpa_printf(MSG_DEBUG, "FT: GTK length mismatch: received %d "
595			   "negotiated %lu",
596			   gtk_elem[2], (unsigned long) keylen);
597		return -1;
598	}
599
600	wpa_hexdump_key(MSG_DEBUG, "FT: GTK from Reassoc Resp", gtk, keylen);
601	if (sm->group_cipher == WPA_CIPHER_TKIP) {
602		/* Swap Tx/Rx keys for Michael MIC */
603		u8 tmp[8];
604		os_memcpy(tmp, gtk + 16, 8);
605		os_memcpy(gtk + 16, gtk + 24, 8);
606		os_memcpy(gtk + 24, tmp, 8);
607	}
608	if (wpa_sm_set_key(sm, alg, broadcast_ether_addr, keyidx, 0,
609			   gtk_elem + 3, rsc_len, gtk, keylen) < 0) {
610		wpa_printf(MSG_WARNING, "WPA: Failed to set GTK to the "
611			   "driver.");
612		return -1;
613	}
614
615	return 0;
616}
617
618
619#ifdef CONFIG_IEEE80211W
620static int wpa_ft_process_igtk_subelem(struct wpa_sm *sm, const u8 *igtk_elem,
621				       size_t igtk_elem_len)
622{
623	u8 igtk[WPA_IGTK_LEN];
624	u16 keyidx;
625
626	if (sm->mgmt_group_cipher != WPA_CIPHER_AES_128_CMAC)
627		return 0;
628
629	if (igtk_elem == NULL) {
630		wpa_printf(MSG_DEBUG, "FT: No IGTK included in FTIE");
631		return 0;
632	}
633
634	wpa_hexdump_key(MSG_DEBUG, "FT: Received IGTK in Reassoc Resp",
635			igtk_elem, igtk_elem_len);
636
637	if (igtk_elem_len != 2 + 6 + 1 + WPA_IGTK_LEN + 8) {
638		wpa_printf(MSG_DEBUG, "FT: Invalid IGTK sub-elem "
639			   "length %lu", (unsigned long) igtk_elem_len);
640		return -1;
641	}
642	if (igtk_elem[8] != WPA_IGTK_LEN) {
643		wpa_printf(MSG_DEBUG, "FT: Invalid IGTK sub-elem Key Length "
644			   "%d", igtk_elem[8]);
645		return -1;
646	}
647
648	if (aes_unwrap(sm->ptk.kek, 16, WPA_IGTK_LEN / 8, igtk_elem + 9, igtk))
649	{
650		wpa_printf(MSG_WARNING, "FT: AES unwrap failed - could not "
651			   "decrypt IGTK");
652		return -1;
653	}
654
655	/* KeyID[2] | IPN[6] | Key Length[1] | Key[16+8] */
656
657	keyidx = WPA_GET_LE16(igtk_elem);
658
659	wpa_hexdump_key(MSG_DEBUG, "FT: IGTK from Reassoc Resp", igtk,
660			WPA_IGTK_LEN);
661	if (wpa_sm_set_key(sm, WPA_ALG_IGTK, broadcast_ether_addr, keyidx, 0,
662			   igtk_elem + 2, 6, igtk, WPA_IGTK_LEN) < 0) {
663		wpa_printf(MSG_WARNING, "WPA: Failed to set IGTK to the "
664			   "driver.");
665		return -1;
666	}
667
668	return 0;
669}
670#endif /* CONFIG_IEEE80211W */
671
672
673int wpa_ft_validate_reassoc_resp(struct wpa_sm *sm, const u8 *ies,
674				 size_t ies_len, const u8 *src_addr)
675{
676	struct wpa_ft_ies parse;
677	struct rsn_mdie *mdie;
678	struct rsn_ftie *ftie;
679	unsigned int count;
680	u8 mic[16];
681
682	wpa_hexdump(MSG_DEBUG, "FT: Response IEs", ies, ies_len);
683
684	if (!wpa_key_mgmt_ft(sm->key_mgmt)) {
685		wpa_printf(MSG_DEBUG, "FT: Reject FT IEs since FT is not "
686			   "enabled for this connection");
687		return -1;
688	}
689
690	if (wpa_ft_parse_ies(ies, ies_len, &parse) < 0) {
691		wpa_printf(MSG_DEBUG, "FT: Failed to parse IEs");
692		return -1;
693	}
694
695	mdie = (struct rsn_mdie *) parse.mdie;
696	if (mdie == NULL || parse.mdie_len < sizeof(*mdie) ||
697	    os_memcmp(mdie->mobility_domain, sm->mobility_domain,
698		      MOBILITY_DOMAIN_ID_LEN) != 0) {
699		wpa_printf(MSG_DEBUG, "FT: Invalid MDIE");
700		return -1;
701	}
702
703	ftie = (struct rsn_ftie *) parse.ftie;
704	if (ftie == NULL || parse.ftie_len < sizeof(*ftie)) {
705		wpa_printf(MSG_DEBUG, "FT: Invalid FTIE");
706		return -1;
707	}
708
709	if (os_memcmp(ftie->snonce, sm->snonce, WPA_NONCE_LEN) != 0) {
710		wpa_printf(MSG_DEBUG, "FT: SNonce mismatch in FTIE");
711		wpa_hexdump(MSG_DEBUG, "FT: Received SNonce",
712			    ftie->snonce, WPA_NONCE_LEN);
713		wpa_hexdump(MSG_DEBUG, "FT: Expected SNonce",
714			    sm->snonce, WPA_NONCE_LEN);
715		return -1;
716	}
717
718	if (os_memcmp(ftie->anonce, sm->anonce, WPA_NONCE_LEN) != 0) {
719		wpa_printf(MSG_DEBUG, "FT: ANonce mismatch in FTIE");
720		wpa_hexdump(MSG_DEBUG, "FT: Received ANonce",
721			    ftie->anonce, WPA_NONCE_LEN);
722		wpa_hexdump(MSG_DEBUG, "FT: Expected ANonce",
723			    sm->anonce, WPA_NONCE_LEN);
724		return -1;
725	}
726
727	if (parse.r0kh_id == NULL) {
728		wpa_printf(MSG_DEBUG, "FT: No R0KH-ID subelem in FTIE");
729		return -1;
730	}
731
732	if (parse.r0kh_id_len != sm->r0kh_id_len ||
733	    os_memcmp_const(parse.r0kh_id, sm->r0kh_id, parse.r0kh_id_len) != 0)
734	{
735		wpa_printf(MSG_DEBUG, "FT: R0KH-ID in FTIE did not match with "
736			   "the current R0KH-ID");
737		wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID in FTIE",
738			    parse.r0kh_id, parse.r0kh_id_len);
739		wpa_hexdump(MSG_DEBUG, "FT: The current R0KH-ID",
740			    sm->r0kh_id, sm->r0kh_id_len);
741		return -1;
742	}
743
744	if (parse.r1kh_id == NULL) {
745		wpa_printf(MSG_DEBUG, "FT: No R1KH-ID subelem in FTIE");
746		return -1;
747	}
748
749	if (os_memcmp_const(parse.r1kh_id, sm->r1kh_id, FT_R1KH_ID_LEN) != 0) {
750		wpa_printf(MSG_DEBUG, "FT: Unknown R1KH-ID used in "
751			   "ReassocResp");
752		return -1;
753	}
754
755	if (parse.rsn_pmkid == NULL ||
756	    os_memcmp_const(parse.rsn_pmkid, sm->pmk_r1_name, WPA_PMK_NAME_LEN))
757	{
758		wpa_printf(MSG_DEBUG, "FT: No matching PMKR1Name (PMKID) in "
759			   "RSNIE (pmkid=%d)", !!parse.rsn_pmkid);
760		return -1;
761	}
762
763	count = 3;
764	if (parse.ric)
765		count += ieee802_11_ie_count(parse.ric, parse.ric_len);
766	if (ftie->mic_control[1] != count) {
767		wpa_printf(MSG_DEBUG, "FT: Unexpected IE count in MIC "
768			   "Control: received %u expected %u",
769			   ftie->mic_control[1], count);
770		return -1;
771	}
772
773	if (wpa_ft_mic(sm->ptk.kck, sm->own_addr, src_addr, 6,
774		       parse.mdie - 2, parse.mdie_len + 2,
775		       parse.ftie - 2, parse.ftie_len + 2,
776		       parse.rsn - 2, parse.rsn_len + 2,
777		       parse.ric, parse.ric_len,
778		       mic) < 0) {
779		wpa_printf(MSG_DEBUG, "FT: Failed to calculate MIC");
780		return -1;
781	}
782
783	if (os_memcmp_const(mic, ftie->mic, 16) != 0) {
784		wpa_printf(MSG_DEBUG, "FT: Invalid MIC in FTIE");
785		wpa_hexdump(MSG_MSGDUMP, "FT: Received MIC", ftie->mic, 16);
786		wpa_hexdump(MSG_MSGDUMP, "FT: Calculated MIC", mic, 16);
787		return -1;
788	}
789
790	if (wpa_ft_process_gtk_subelem(sm, parse.gtk, parse.gtk_len) < 0)
791		return -1;
792
793#ifdef CONFIG_IEEE80211W
794	if (wpa_ft_process_igtk_subelem(sm, parse.igtk, parse.igtk_len) < 0)
795		return -1;
796#endif /* CONFIG_IEEE80211W */
797
798	if (sm->set_ptk_after_assoc) {
799		wpa_printf(MSG_DEBUG, "FT: Try to set PTK again now that we "
800			   "are associated");
801		if (wpa_ft_install_ptk(sm, src_addr) < 0)
802			return -1;
803		sm->set_ptk_after_assoc = 0;
804	}
805
806	if (parse.ric) {
807		wpa_hexdump(MSG_MSGDUMP, "FT: RIC Response",
808			    parse.ric, parse.ric_len);
809		/* TODO: parse response and inform driver about results when
810		 * using wpa_supplicant SME */
811	}
812
813	wpa_printf(MSG_DEBUG, "FT: Completed successfully");
814
815	return 0;
816}
817
818
819/**
820 * wpa_ft_start_over_ds - Generate over-the-DS auth request
821 * @sm: Pointer to WPA state machine data from wpa_sm_init()
822 * @target_ap: Target AP Address
823 * @mdie: Mobility Domain IE from the target AP
824 * Returns: 0 on success, -1 on failure
825 */
826int wpa_ft_start_over_ds(struct wpa_sm *sm, const u8 *target_ap,
827			 const u8 *mdie)
828{
829	u8 *ft_ies;
830	size_t ft_ies_len;
831
832	wpa_printf(MSG_DEBUG, "FT: Request over-the-DS with " MACSTR,
833		   MAC2STR(target_ap));
834
835	/* Generate a new SNonce */
836	if (random_get_bytes(sm->snonce, WPA_NONCE_LEN)) {
837		wpa_printf(MSG_INFO, "FT: Failed to generate a new SNonce");
838		return -1;
839	}
840
841	ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, NULL, sm->pmk_r0_name,
842				    NULL, target_ap, NULL, 0, mdie);
843	if (ft_ies) {
844		sm->over_the_ds_in_progress = 1;
845		os_memcpy(sm->target_ap, target_ap, ETH_ALEN);
846		wpa_sm_send_ft_action(sm, 1, target_ap, ft_ies, ft_ies_len);
847		os_free(ft_ies);
848	}
849
850	return 0;
851}
852
853#endif /* CONFIG_IEEE80211R */
854