1/*
2 * WPA Supplicant - IEEE 802.11r - Fast BSS Transition
3 * Copyright (c) 2006-2015, 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, struct wpa_ptk *ptk)
23{
24	u8 ptk_name[WPA_PMK_NAME_LEN];
25	const u8 *anonce = key->key_nonce;
26
27	if (sm->xxkey_len == 0) {
28		wpa_printf(MSG_DEBUG, "FT: XXKey not available for key "
29			   "derivation");
30		return -1;
31	}
32
33	wpa_derive_pmk_r0(sm->xxkey, sm->xxkey_len, sm->ssid,
34			  sm->ssid_len, sm->mobility_domain,
35			  sm->r0kh_id, sm->r0kh_id_len, sm->own_addr,
36			  sm->pmk_r0, sm->pmk_r0_name);
37	wpa_hexdump_key(MSG_DEBUG, "FT: PMK-R0", sm->pmk_r0, PMK_LEN);
38	wpa_hexdump(MSG_DEBUG, "FT: PMKR0Name",
39		    sm->pmk_r0_name, WPA_PMK_NAME_LEN);
40	wpa_derive_pmk_r1(sm->pmk_r0, sm->pmk_r0_name, sm->r1kh_id,
41			  sm->own_addr, sm->pmk_r1, sm->pmk_r1_name);
42	wpa_hexdump_key(MSG_DEBUG, "FT: PMK-R1", sm->pmk_r1, PMK_LEN);
43	wpa_hexdump(MSG_DEBUG, "FT: PMKR1Name", sm->pmk_r1_name,
44		    WPA_PMK_NAME_LEN);
45	return wpa_pmk_r1_to_ptk(sm->pmk_r1, sm->snonce, anonce, sm->own_addr,
46				 sm->bssid, sm->pmk_r1_name, ptk, ptk_name,
47				 sm->key_mgmt, sm->pairwise_cipher);
48}
49
50
51/**
52 * wpa_sm_set_ft_params - Set FT (IEEE 802.11r) parameters
53 * @sm: Pointer to WPA state machine data from wpa_sm_init()
54 * @ies: Association Response IEs or %NULL to clear FT parameters
55 * @ies_len: Length of ies buffer in octets
56 * Returns: 0 on success, -1 on failure
57 */
58int wpa_sm_set_ft_params(struct wpa_sm *sm, const u8 *ies, size_t ies_len)
59{
60	struct wpa_ft_ies ft;
61
62	if (sm == NULL)
63		return 0;
64
65	if (wpa_ft_parse_ies(ies, ies_len, &ft) < 0)
66		return -1;
67
68	if (ft.mdie && ft.mdie_len < MOBILITY_DOMAIN_ID_LEN + 1)
69		return -1;
70
71	if (ft.mdie) {
72		wpa_hexdump(MSG_DEBUG, "FT: Mobility domain",
73			    ft.mdie, MOBILITY_DOMAIN_ID_LEN);
74		os_memcpy(sm->mobility_domain, ft.mdie,
75			  MOBILITY_DOMAIN_ID_LEN);
76		sm->mdie_ft_capab = ft.mdie[MOBILITY_DOMAIN_ID_LEN];
77		wpa_printf(MSG_DEBUG, "FT: Capability and Policy: 0x%02x",
78			   sm->mdie_ft_capab);
79	} else
80		os_memset(sm->mobility_domain, 0, MOBILITY_DOMAIN_ID_LEN);
81
82	if (ft.r0kh_id) {
83		wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID",
84			    ft.r0kh_id, ft.r0kh_id_len);
85		os_memcpy(sm->r0kh_id, ft.r0kh_id, ft.r0kh_id_len);
86		sm->r0kh_id_len = ft.r0kh_id_len;
87	} else {
88		/* FIX: When should R0KH-ID be cleared? We need to keep the
89		 * old R0KH-ID in order to be able to use this during FT. */
90		/*
91		 * os_memset(sm->r0kh_id, 0, FT_R0KH_ID_LEN);
92		 * sm->r0kh_id_len = 0;
93		 */
94	}
95
96	if (ft.r1kh_id) {
97		wpa_hexdump(MSG_DEBUG, "FT: R1KH-ID",
98			    ft.r1kh_id, FT_R1KH_ID_LEN);
99		os_memcpy(sm->r1kh_id, ft.r1kh_id, FT_R1KH_ID_LEN);
100	} else
101		os_memset(sm->r1kh_id, 0, FT_R1KH_ID_LEN);
102
103	os_free(sm->assoc_resp_ies);
104	sm->assoc_resp_ies = os_malloc(ft.mdie_len + 2 + ft.ftie_len + 2);
105	if (sm->assoc_resp_ies) {
106		u8 *pos = sm->assoc_resp_ies;
107		if (ft.mdie) {
108			os_memcpy(pos, ft.mdie - 2, ft.mdie_len + 2);
109			pos += ft.mdie_len + 2;
110		}
111		if (ft.ftie) {
112			os_memcpy(pos, ft.ftie - 2, ft.ftie_len + 2);
113			pos += ft.ftie_len + 2;
114		}
115		sm->assoc_resp_ies_len = pos - sm->assoc_resp_ies;
116		wpa_hexdump(MSG_DEBUG, "FT: Stored MDIE and FTIE from "
117			    "(Re)Association Response",
118			    sm->assoc_resp_ies, sm->assoc_resp_ies_len);
119	}
120
121	return 0;
122}
123
124
125/**
126 * wpa_ft_gen_req_ies - Generate FT (IEEE 802.11r) IEs for Auth/ReAssoc Request
127 * @sm: Pointer to WPA state machine data from wpa_sm_init()
128 * @len: Buffer for returning the length of the IEs
129 * @anonce: ANonce or %NULL if not yet available
130 * @pmk_name: PMKR0Name or PMKR1Name to be added into the RSN IE PMKID List
131 * @kck: 128-bit KCK for MIC or %NULL if no MIC is used
132 * @kck_len: KCK length in octets
133 * @target_ap: Target AP address
134 * @ric_ies: Optional IE(s), e.g., WMM TSPEC(s), for RIC-Request or %NULL
135 * @ric_ies_len: Length of ric_ies buffer in octets
136 * @ap_mdie: Mobility Domain IE from the target AP
137 * Returns: Pointer to buffer with IEs or %NULL on failure
138 *
139 * Caller is responsible for freeing the returned buffer with os_free();
140 */
141static u8 * wpa_ft_gen_req_ies(struct wpa_sm *sm, size_t *len,
142			       const u8 *anonce, const u8 *pmk_name,
143			       const u8 *kck, size_t kck_len,
144			       const u8 *target_ap,
145			       const u8 *ric_ies, size_t ric_ies_len,
146			       const u8 *ap_mdie)
147{
148	size_t buf_len;
149	u8 *buf, *pos, *ftie_len, *ftie_pos;
150	struct rsn_mdie *mdie;
151	struct rsn_ftie *ftie;
152	struct rsn_ie_hdr *rsnie;
153	u16 capab;
154
155	sm->ft_completed = 0;
156
157	buf_len = 2 + sizeof(struct rsn_mdie) + 2 + sizeof(struct rsn_ftie) +
158		2 + sm->r0kh_id_len + ric_ies_len + 100;
159	buf = os_zalloc(buf_len);
160	if (buf == NULL)
161		return NULL;
162	pos = buf;
163
164	/* RSNIE[PMKR0Name/PMKR1Name] */
165	rsnie = (struct rsn_ie_hdr *) pos;
166	rsnie->elem_id = WLAN_EID_RSN;
167	WPA_PUT_LE16(rsnie->version, RSN_VERSION);
168	pos = (u8 *) (rsnie + 1);
169
170	/* Group Suite Selector */
171	if (sm->group_cipher != WPA_CIPHER_CCMP &&
172	    sm->group_cipher != WPA_CIPHER_GCMP &&
173	    sm->group_cipher != WPA_CIPHER_TKIP) {
174		wpa_printf(MSG_WARNING, "FT: Invalid group cipher (%d)",
175			   sm->group_cipher);
176		os_free(buf);
177		return NULL;
178	}
179	RSN_SELECTOR_PUT(pos, wpa_cipher_to_suite(WPA_PROTO_RSN,
180						  sm->group_cipher));
181	pos += RSN_SELECTOR_LEN;
182
183	/* Pairwise Suite Count */
184	WPA_PUT_LE16(pos, 1);
185	pos += 2;
186
187	/* Pairwise Suite List */
188	if (!wpa_cipher_valid_pairwise(sm->pairwise_cipher)) {
189		wpa_printf(MSG_WARNING, "FT: Invalid pairwise cipher (%d)",
190			   sm->pairwise_cipher);
191		os_free(buf);
192		return NULL;
193	}
194	RSN_SELECTOR_PUT(pos, wpa_cipher_to_suite(WPA_PROTO_RSN,
195						  sm->pairwise_cipher));
196	pos += RSN_SELECTOR_LEN;
197
198	/* Authenticated Key Management Suite Count */
199	WPA_PUT_LE16(pos, 1);
200	pos += 2;
201
202	/* Authenticated Key Management Suite List */
203	if (sm->key_mgmt == WPA_KEY_MGMT_FT_IEEE8021X)
204		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_802_1X);
205	else if (sm->key_mgmt == WPA_KEY_MGMT_FT_PSK)
206		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_PSK);
207	else if (sm->key_mgmt == WPA_KEY_MGMT_FT_SAE)
208		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_SAE);
209	else {
210		wpa_printf(MSG_WARNING, "FT: Invalid key management type (%d)",
211			   sm->key_mgmt);
212		os_free(buf);
213		return NULL;
214	}
215	pos += RSN_SELECTOR_LEN;
216
217	/* RSN Capabilities */
218	capab = 0;
219#ifdef CONFIG_IEEE80211W
220	if (sm->mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC)
221		capab |= WPA_CAPABILITY_MFPC;
222#endif /* CONFIG_IEEE80211W */
223	WPA_PUT_LE16(pos, capab);
224	pos += 2;
225
226	/* PMKID Count */
227	WPA_PUT_LE16(pos, 1);
228	pos += 2;
229
230	/* PMKID List [PMKR0Name/PMKR1Name] */
231	os_memcpy(pos, pmk_name, WPA_PMK_NAME_LEN);
232	pos += WPA_PMK_NAME_LEN;
233
234#ifdef CONFIG_IEEE80211W
235	if (sm->mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC) {
236		/* Management Group Cipher Suite */
237		RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_AES_128_CMAC);
238		pos += RSN_SELECTOR_LEN;
239	}
240#endif /* CONFIG_IEEE80211W */
241
242	rsnie->len = (pos - (u8 *) rsnie) - 2;
243
244	/* MDIE */
245	*pos++ = WLAN_EID_MOBILITY_DOMAIN;
246	*pos++ = sizeof(*mdie);
247	mdie = (struct rsn_mdie *) pos;
248	pos += sizeof(*mdie);
249	os_memcpy(mdie->mobility_domain, sm->mobility_domain,
250		  MOBILITY_DOMAIN_ID_LEN);
251	mdie->ft_capab = ap_mdie && ap_mdie[1] >= 3 ? ap_mdie[4] :
252		sm->mdie_ft_capab;
253
254	/* FTIE[SNonce, [R1KH-ID,] R0KH-ID ] */
255	ftie_pos = pos;
256	*pos++ = WLAN_EID_FAST_BSS_TRANSITION;
257	ftie_len = pos++;
258	ftie = (struct rsn_ftie *) pos;
259	pos += sizeof(*ftie);
260	os_memcpy(ftie->snonce, sm->snonce, WPA_NONCE_LEN);
261	if (anonce)
262		os_memcpy(ftie->anonce, anonce, WPA_NONCE_LEN);
263	if (kck) {
264		/* R1KH-ID sub-element in third FT message */
265		*pos++ = FTIE_SUBELEM_R1KH_ID;
266		*pos++ = FT_R1KH_ID_LEN;
267		os_memcpy(pos, sm->r1kh_id, FT_R1KH_ID_LEN);
268		pos += FT_R1KH_ID_LEN;
269	}
270	/* R0KH-ID sub-element */
271	*pos++ = FTIE_SUBELEM_R0KH_ID;
272	*pos++ = sm->r0kh_id_len;
273	os_memcpy(pos, sm->r0kh_id, sm->r0kh_id_len);
274	pos += sm->r0kh_id_len;
275	*ftie_len = pos - ftie_len - 1;
276
277	if (ric_ies) {
278		/* RIC Request */
279		os_memcpy(pos, ric_ies, ric_ies_len);
280		pos += ric_ies_len;
281	}
282
283	if (kck) {
284		/*
285		 * IEEE Std 802.11r-2008, 11A.8.4
286		 * MIC shall be calculated over:
287		 * non-AP STA MAC address
288		 * Target AP MAC address
289		 * Transaction seq number (5 for ReassocReq, 3 otherwise)
290		 * RSN IE
291		 * MDIE
292		 * FTIE (with MIC field set to 0)
293		 * RIC-Request (if present)
294		 */
295		/* Information element count */
296		ftie->mic_control[1] = 3 + ieee802_11_ie_count(ric_ies,
297							       ric_ies_len);
298		if (wpa_ft_mic(kck, kck_len, sm->own_addr, target_ap, 5,
299			       ((u8 *) mdie) - 2, 2 + sizeof(*mdie),
300			       ftie_pos, 2 + *ftie_len,
301			       (u8 *) rsnie, 2 + rsnie->len, ric_ies,
302			       ric_ies_len, ftie->mic) < 0) {
303			wpa_printf(MSG_INFO, "FT: Failed to calculate MIC");
304			os_free(buf);
305			return NULL;
306		}
307	}
308
309	*len = pos - buf;
310
311	return buf;
312}
313
314
315static int wpa_ft_install_ptk(struct wpa_sm *sm, const u8 *bssid)
316{
317	int keylen;
318	enum wpa_alg alg;
319	u8 null_rsc[6] = { 0, 0, 0, 0, 0, 0 };
320
321	wpa_printf(MSG_DEBUG, "FT: Installing PTK to the driver.");
322
323	if (!wpa_cipher_valid_pairwise(sm->pairwise_cipher)) {
324		wpa_printf(MSG_WARNING, "FT: Unsupported pairwise cipher %d",
325			   sm->pairwise_cipher);
326		return -1;
327	}
328
329	alg = wpa_cipher_to_alg(sm->pairwise_cipher);
330	keylen = wpa_cipher_key_len(sm->pairwise_cipher);
331
332	if (wpa_sm_set_key(sm, alg, bssid, 0, 1, null_rsc,
333			   sizeof(null_rsc), (u8 *) sm->ptk.tk, keylen) < 0) {
334		wpa_printf(MSG_WARNING, "FT: Failed to set PTK to the driver");
335		return -1;
336	}
337
338	return 0;
339}
340
341
342/**
343 * wpa_ft_prepare_auth_request - Generate over-the-air auth request
344 * @sm: Pointer to WPA state machine data from wpa_sm_init()
345 * @mdie: Target AP MDIE
346 * Returns: 0 on success, -1 on failure
347 */
348int wpa_ft_prepare_auth_request(struct wpa_sm *sm, const u8 *mdie)
349{
350	u8 *ft_ies;
351	size_t ft_ies_len;
352
353	/* Generate a new SNonce */
354	if (random_get_bytes(sm->snonce, WPA_NONCE_LEN)) {
355		wpa_printf(MSG_INFO, "FT: Failed to generate a new SNonce");
356		return -1;
357	}
358
359	ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, NULL, sm->pmk_r0_name,
360				    NULL, 0, sm->bssid, NULL, 0, mdie);
361	if (ft_ies) {
362		wpa_sm_update_ft_ies(sm, sm->mobility_domain,
363				     ft_ies, ft_ies_len);
364		os_free(ft_ies);
365	}
366
367	return 0;
368}
369
370
371int wpa_ft_process_response(struct wpa_sm *sm, const u8 *ies, size_t ies_len,
372			    int ft_action, const u8 *target_ap,
373			    const u8 *ric_ies, size_t ric_ies_len)
374{
375	u8 *ft_ies;
376	size_t ft_ies_len;
377	struct wpa_ft_ies parse;
378	struct rsn_mdie *mdie;
379	struct rsn_ftie *ftie;
380	u8 ptk_name[WPA_PMK_NAME_LEN];
381	int ret;
382	const u8 *bssid;
383
384	wpa_hexdump(MSG_DEBUG, "FT: Response IEs", ies, ies_len);
385	wpa_hexdump(MSG_DEBUG, "FT: RIC IEs", ric_ies, ric_ies_len);
386
387	if (ft_action) {
388		if (!sm->over_the_ds_in_progress) {
389			wpa_printf(MSG_DEBUG, "FT: No over-the-DS in progress "
390				   "- drop FT Action Response");
391			return -1;
392		}
393
394		if (os_memcmp(target_ap, sm->target_ap, ETH_ALEN) != 0) {
395			wpa_printf(MSG_DEBUG, "FT: No over-the-DS in progress "
396				   "with this Target AP - drop FT Action "
397				   "Response");
398			return -1;
399		}
400	}
401
402	if (!wpa_key_mgmt_ft(sm->key_mgmt)) {
403		wpa_printf(MSG_DEBUG, "FT: Reject FT IEs since FT is not "
404			   "enabled for this connection");
405		return -1;
406	}
407
408	if (wpa_ft_parse_ies(ies, ies_len, &parse) < 0) {
409		wpa_printf(MSG_DEBUG, "FT: Failed to parse IEs");
410		return -1;
411	}
412
413	mdie = (struct rsn_mdie *) parse.mdie;
414	if (mdie == NULL || parse.mdie_len < sizeof(*mdie) ||
415	    os_memcmp(mdie->mobility_domain, sm->mobility_domain,
416		      MOBILITY_DOMAIN_ID_LEN) != 0) {
417		wpa_printf(MSG_DEBUG, "FT: Invalid MDIE");
418		return -1;
419	}
420
421	ftie = (struct rsn_ftie *) parse.ftie;
422	if (ftie == NULL || parse.ftie_len < sizeof(*ftie)) {
423		wpa_printf(MSG_DEBUG, "FT: Invalid FTIE");
424		return -1;
425	}
426
427	if (os_memcmp(ftie->snonce, sm->snonce, WPA_NONCE_LEN) != 0) {
428		wpa_printf(MSG_DEBUG, "FT: SNonce mismatch in FTIE");
429		wpa_hexdump(MSG_DEBUG, "FT: Received SNonce",
430			    ftie->snonce, WPA_NONCE_LEN);
431		wpa_hexdump(MSG_DEBUG, "FT: Expected SNonce",
432			    sm->snonce, WPA_NONCE_LEN);
433		return -1;
434	}
435
436	if (parse.r0kh_id == NULL) {
437		wpa_printf(MSG_DEBUG, "FT: No R0KH-ID subelem in FTIE");
438		return -1;
439	}
440
441	if (parse.r0kh_id_len != sm->r0kh_id_len ||
442	    os_memcmp_const(parse.r0kh_id, sm->r0kh_id, parse.r0kh_id_len) != 0)
443	{
444		wpa_printf(MSG_DEBUG, "FT: R0KH-ID in FTIE did not match with "
445			   "the current R0KH-ID");
446		wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID in FTIE",
447			    parse.r0kh_id, parse.r0kh_id_len);
448		wpa_hexdump(MSG_DEBUG, "FT: The current R0KH-ID",
449			    sm->r0kh_id, sm->r0kh_id_len);
450		return -1;
451	}
452
453	if (parse.r1kh_id == NULL) {
454		wpa_printf(MSG_DEBUG, "FT: No R1KH-ID subelem in FTIE");
455		return -1;
456	}
457
458	if (parse.rsn_pmkid == NULL ||
459	    os_memcmp_const(parse.rsn_pmkid, sm->pmk_r0_name, WPA_PMK_NAME_LEN))
460	{
461		wpa_printf(MSG_DEBUG, "FT: No matching PMKR0Name (PMKID) in "
462			   "RSNIE");
463		return -1;
464	}
465
466	os_memcpy(sm->r1kh_id, parse.r1kh_id, FT_R1KH_ID_LEN);
467	wpa_hexdump(MSG_DEBUG, "FT: R1KH-ID", sm->r1kh_id, FT_R1KH_ID_LEN);
468	wpa_hexdump(MSG_DEBUG, "FT: SNonce", sm->snonce, WPA_NONCE_LEN);
469	wpa_hexdump(MSG_DEBUG, "FT: ANonce", ftie->anonce, WPA_NONCE_LEN);
470	os_memcpy(sm->anonce, ftie->anonce, WPA_NONCE_LEN);
471	wpa_derive_pmk_r1(sm->pmk_r0, sm->pmk_r0_name, sm->r1kh_id,
472			  sm->own_addr, sm->pmk_r1, sm->pmk_r1_name);
473	wpa_hexdump_key(MSG_DEBUG, "FT: PMK-R1", sm->pmk_r1, PMK_LEN);
474	wpa_hexdump(MSG_DEBUG, "FT: PMKR1Name",
475		    sm->pmk_r1_name, WPA_PMK_NAME_LEN);
476
477	bssid = target_ap;
478	if (wpa_pmk_r1_to_ptk(sm->pmk_r1, sm->snonce, ftie->anonce,
479			      sm->own_addr, bssid, sm->pmk_r1_name, &sm->ptk,
480			      ptk_name, sm->key_mgmt, sm->pairwise_cipher) < 0)
481		return -1;
482
483	ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, ftie->anonce,
484				    sm->pmk_r1_name,
485				    sm->ptk.kck, sm->ptk.kck_len, bssid,
486				    ric_ies, ric_ies_len,
487				    parse.mdie ? parse.mdie - 2 : NULL);
488	if (ft_ies) {
489		wpa_sm_update_ft_ies(sm, sm->mobility_domain,
490				     ft_ies, ft_ies_len);
491		os_free(ft_ies);
492	}
493
494	wpa_sm_mark_authenticated(sm, bssid);
495	ret = wpa_ft_install_ptk(sm, bssid);
496	if (ret) {
497		/*
498		 * Some drivers do not support key configuration when we are
499		 * not associated with the target AP. Work around this by
500		 * trying again after the following reassociation gets
501		 * completed.
502		 */
503		wpa_printf(MSG_DEBUG, "FT: Failed to set PTK prior to "
504			   "association - try again after reassociation");
505		sm->set_ptk_after_assoc = 1;
506	} else
507		sm->set_ptk_after_assoc = 0;
508
509	sm->ft_completed = 1;
510	if (ft_action) {
511		/*
512		 * The caller is expected trigger re-association with the
513		 * Target AP.
514		 */
515		os_memcpy(sm->bssid, target_ap, ETH_ALEN);
516	}
517
518	return 0;
519}
520
521
522int wpa_ft_is_completed(struct wpa_sm *sm)
523{
524	if (sm == NULL)
525		return 0;
526
527	if (!wpa_key_mgmt_ft(sm->key_mgmt))
528		return 0;
529
530	return sm->ft_completed;
531}
532
533
534void wpa_reset_ft_completed(struct wpa_sm *sm)
535{
536	if (sm != NULL)
537		sm->ft_completed = 0;
538}
539
540
541static int wpa_ft_process_gtk_subelem(struct wpa_sm *sm, const u8 *gtk_elem,
542				      size_t gtk_elem_len)
543{
544	u8 gtk[32];
545	int keyidx;
546	enum wpa_alg alg;
547	size_t gtk_len, keylen, rsc_len;
548
549	if (gtk_elem == NULL) {
550		wpa_printf(MSG_DEBUG, "FT: No GTK included in FTIE");
551		return 0;
552	}
553
554	wpa_hexdump_key(MSG_DEBUG, "FT: Received GTK in Reassoc Resp",
555			gtk_elem, gtk_elem_len);
556
557	if (gtk_elem_len < 11 + 24 || (gtk_elem_len - 11) % 8 ||
558	    gtk_elem_len - 19 > sizeof(gtk)) {
559		wpa_printf(MSG_DEBUG, "FT: Invalid GTK sub-elem "
560			   "length %lu", (unsigned long) gtk_elem_len);
561		return -1;
562	}
563	gtk_len = gtk_elem_len - 19;
564	if (aes_unwrap(sm->ptk.kek, sm->ptk.kek_len, gtk_len / 8, gtk_elem + 11,
565		       gtk)) {
566		wpa_printf(MSG_WARNING, "FT: AES unwrap failed - could not "
567			   "decrypt GTK");
568		return -1;
569	}
570
571	keylen = wpa_cipher_key_len(sm->group_cipher);
572	rsc_len = wpa_cipher_rsc_len(sm->group_cipher);
573	alg = wpa_cipher_to_alg(sm->group_cipher);
574	if (alg == WPA_ALG_NONE) {
575		wpa_printf(MSG_WARNING, "WPA: Unsupported Group Cipher %d",
576			   sm->group_cipher);
577		return -1;
578	}
579
580	if (gtk_len < keylen) {
581		wpa_printf(MSG_DEBUG, "FT: Too short GTK in FTIE");
582		return -1;
583	}
584
585	/* Key Info[2] | Key Length[1] | RSC[8] | Key[5..32]. */
586
587	keyidx = WPA_GET_LE16(gtk_elem) & 0x03;
588
589	if (gtk_elem[2] != keylen) {
590		wpa_printf(MSG_DEBUG, "FT: GTK length mismatch: received %d "
591			   "negotiated %lu",
592			   gtk_elem[2], (unsigned long) keylen);
593		return -1;
594	}
595
596	wpa_hexdump_key(MSG_DEBUG, "FT: GTK from Reassoc Resp", gtk, keylen);
597	if (sm->group_cipher == WPA_CIPHER_TKIP) {
598		/* Swap Tx/Rx keys for Michael MIC */
599		u8 tmp[8];
600		os_memcpy(tmp, gtk + 16, 8);
601		os_memcpy(gtk + 16, gtk + 24, 8);
602		os_memcpy(gtk + 24, tmp, 8);
603	}
604	if (wpa_sm_set_key(sm, alg, broadcast_ether_addr, keyidx, 0,
605			   gtk_elem + 3, rsc_len, gtk, keylen) < 0) {
606		wpa_printf(MSG_WARNING, "WPA: Failed to set GTK to the "
607			   "driver.");
608		return -1;
609	}
610
611	return 0;
612}
613
614
615#ifdef CONFIG_IEEE80211W
616static int wpa_ft_process_igtk_subelem(struct wpa_sm *sm, const u8 *igtk_elem,
617				       size_t igtk_elem_len)
618{
619	u8 igtk[WPA_IGTK_LEN];
620	u16 keyidx;
621
622	if (sm->mgmt_group_cipher != WPA_CIPHER_AES_128_CMAC)
623		return 0;
624
625	if (igtk_elem == NULL) {
626		wpa_printf(MSG_DEBUG, "FT: No IGTK included in FTIE");
627		return 0;
628	}
629
630	wpa_hexdump_key(MSG_DEBUG, "FT: Received IGTK in Reassoc Resp",
631			igtk_elem, igtk_elem_len);
632
633	if (igtk_elem_len != 2 + 6 + 1 + WPA_IGTK_LEN + 8) {
634		wpa_printf(MSG_DEBUG, "FT: Invalid IGTK sub-elem "
635			   "length %lu", (unsigned long) igtk_elem_len);
636		return -1;
637	}
638	if (igtk_elem[8] != WPA_IGTK_LEN) {
639		wpa_printf(MSG_DEBUG, "FT: Invalid IGTK sub-elem Key Length "
640			   "%d", igtk_elem[8]);
641		return -1;
642	}
643
644	if (aes_unwrap(sm->ptk.kek, sm->ptk.kek_len, WPA_IGTK_LEN / 8,
645		       igtk_elem + 9, igtk)) {
646		wpa_printf(MSG_WARNING, "FT: AES unwrap failed - could not "
647			   "decrypt IGTK");
648		return -1;
649	}
650
651	/* KeyID[2] | IPN[6] | Key Length[1] | Key[16+8] */
652
653	keyidx = WPA_GET_LE16(igtk_elem);
654
655	wpa_hexdump_key(MSG_DEBUG, "FT: IGTK from Reassoc Resp", igtk,
656			WPA_IGTK_LEN);
657	if (wpa_sm_set_key(sm, WPA_ALG_IGTK, broadcast_ether_addr, keyidx, 0,
658			   igtk_elem + 2, 6, igtk, WPA_IGTK_LEN) < 0) {
659		wpa_printf(MSG_WARNING, "WPA: Failed to set IGTK to the "
660			   "driver.");
661		return -1;
662	}
663
664	return 0;
665}
666#endif /* CONFIG_IEEE80211W */
667
668
669int wpa_ft_validate_reassoc_resp(struct wpa_sm *sm, const u8 *ies,
670				 size_t ies_len, const u8 *src_addr)
671{
672	struct wpa_ft_ies parse;
673	struct rsn_mdie *mdie;
674	struct rsn_ftie *ftie;
675	unsigned int count;
676	u8 mic[WPA_EAPOL_KEY_MIC_MAX_LEN];
677
678	wpa_hexdump(MSG_DEBUG, "FT: Response IEs", ies, ies_len);
679
680	if (!wpa_key_mgmt_ft(sm->key_mgmt)) {
681		wpa_printf(MSG_DEBUG, "FT: Reject FT IEs since FT is not "
682			   "enabled for this connection");
683		return -1;
684	}
685
686	if (wpa_ft_parse_ies(ies, ies_len, &parse) < 0) {
687		wpa_printf(MSG_DEBUG, "FT: Failed to parse IEs");
688		return -1;
689	}
690
691	mdie = (struct rsn_mdie *) parse.mdie;
692	if (mdie == NULL || parse.mdie_len < sizeof(*mdie) ||
693	    os_memcmp(mdie->mobility_domain, sm->mobility_domain,
694		      MOBILITY_DOMAIN_ID_LEN) != 0) {
695		wpa_printf(MSG_DEBUG, "FT: Invalid MDIE");
696		return -1;
697	}
698
699	ftie = (struct rsn_ftie *) parse.ftie;
700	if (ftie == NULL || parse.ftie_len < sizeof(*ftie)) {
701		wpa_printf(MSG_DEBUG, "FT: Invalid FTIE");
702		return -1;
703	}
704
705	if (os_memcmp(ftie->snonce, sm->snonce, WPA_NONCE_LEN) != 0) {
706		wpa_printf(MSG_DEBUG, "FT: SNonce mismatch in FTIE");
707		wpa_hexdump(MSG_DEBUG, "FT: Received SNonce",
708			    ftie->snonce, WPA_NONCE_LEN);
709		wpa_hexdump(MSG_DEBUG, "FT: Expected SNonce",
710			    sm->snonce, WPA_NONCE_LEN);
711		return -1;
712	}
713
714	if (os_memcmp(ftie->anonce, sm->anonce, WPA_NONCE_LEN) != 0) {
715		wpa_printf(MSG_DEBUG, "FT: ANonce mismatch in FTIE");
716		wpa_hexdump(MSG_DEBUG, "FT: Received ANonce",
717			    ftie->anonce, WPA_NONCE_LEN);
718		wpa_hexdump(MSG_DEBUG, "FT: Expected ANonce",
719			    sm->anonce, WPA_NONCE_LEN);
720		return -1;
721	}
722
723	if (parse.r0kh_id == NULL) {
724		wpa_printf(MSG_DEBUG, "FT: No R0KH-ID subelem in FTIE");
725		return -1;
726	}
727
728	if (parse.r0kh_id_len != sm->r0kh_id_len ||
729	    os_memcmp_const(parse.r0kh_id, sm->r0kh_id, parse.r0kh_id_len) != 0)
730	{
731		wpa_printf(MSG_DEBUG, "FT: R0KH-ID in FTIE did not match with "
732			   "the current R0KH-ID");
733		wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID in FTIE",
734			    parse.r0kh_id, parse.r0kh_id_len);
735		wpa_hexdump(MSG_DEBUG, "FT: The current R0KH-ID",
736			    sm->r0kh_id, sm->r0kh_id_len);
737		return -1;
738	}
739
740	if (parse.r1kh_id == NULL) {
741		wpa_printf(MSG_DEBUG, "FT: No R1KH-ID subelem in FTIE");
742		return -1;
743	}
744
745	if (os_memcmp_const(parse.r1kh_id, sm->r1kh_id, FT_R1KH_ID_LEN) != 0) {
746		wpa_printf(MSG_DEBUG, "FT: Unknown R1KH-ID used in "
747			   "ReassocResp");
748		return -1;
749	}
750
751	if (parse.rsn_pmkid == NULL ||
752	    os_memcmp_const(parse.rsn_pmkid, sm->pmk_r1_name, WPA_PMK_NAME_LEN))
753	{
754		wpa_printf(MSG_DEBUG, "FT: No matching PMKR1Name (PMKID) in "
755			   "RSNIE (pmkid=%d)", !!parse.rsn_pmkid);
756		return -1;
757	}
758
759	count = 3;
760	if (parse.ric)
761		count += ieee802_11_ie_count(parse.ric, parse.ric_len);
762	if (ftie->mic_control[1] != count) {
763		wpa_printf(MSG_DEBUG, "FT: Unexpected IE count in MIC "
764			   "Control: received %u expected %u",
765			   ftie->mic_control[1], count);
766		return -1;
767	}
768
769	if (wpa_ft_mic(sm->ptk.kck, sm->ptk.kck_len, sm->own_addr, src_addr, 6,
770		       parse.mdie - 2, parse.mdie_len + 2,
771		       parse.ftie - 2, parse.ftie_len + 2,
772		       parse.rsn - 2, parse.rsn_len + 2,
773		       parse.ric, parse.ric_len,
774		       mic) < 0) {
775		wpa_printf(MSG_DEBUG, "FT: Failed to calculate MIC");
776		return -1;
777	}
778
779	if (os_memcmp_const(mic, ftie->mic, 16) != 0) {
780		wpa_printf(MSG_DEBUG, "FT: Invalid MIC in FTIE");
781		wpa_hexdump(MSG_MSGDUMP, "FT: Received MIC", ftie->mic, 16);
782		wpa_hexdump(MSG_MSGDUMP, "FT: Calculated MIC", mic, 16);
783		return -1;
784	}
785
786	if (wpa_ft_process_gtk_subelem(sm, parse.gtk, parse.gtk_len) < 0)
787		return -1;
788
789#ifdef CONFIG_IEEE80211W
790	if (wpa_ft_process_igtk_subelem(sm, parse.igtk, parse.igtk_len) < 0)
791		return -1;
792#endif /* CONFIG_IEEE80211W */
793
794	if (sm->set_ptk_after_assoc) {
795		wpa_printf(MSG_DEBUG, "FT: Try to set PTK again now that we "
796			   "are associated");
797		if (wpa_ft_install_ptk(sm, src_addr) < 0)
798			return -1;
799		sm->set_ptk_after_assoc = 0;
800	}
801
802	if (parse.ric) {
803		wpa_hexdump(MSG_MSGDUMP, "FT: RIC Response",
804			    parse.ric, parse.ric_len);
805		/* TODO: parse response and inform driver about results when
806		 * using wpa_supplicant SME */
807	}
808
809	wpa_printf(MSG_DEBUG, "FT: Completed successfully");
810
811	return 0;
812}
813
814
815/**
816 * wpa_ft_start_over_ds - Generate over-the-DS auth request
817 * @sm: Pointer to WPA state machine data from wpa_sm_init()
818 * @target_ap: Target AP Address
819 * @mdie: Mobility Domain IE from the target AP
820 * Returns: 0 on success, -1 on failure
821 */
822int wpa_ft_start_over_ds(struct wpa_sm *sm, const u8 *target_ap,
823			 const u8 *mdie)
824{
825	u8 *ft_ies;
826	size_t ft_ies_len;
827
828	wpa_printf(MSG_DEBUG, "FT: Request over-the-DS with " MACSTR,
829		   MAC2STR(target_ap));
830
831	/* Generate a new SNonce */
832	if (random_get_bytes(sm->snonce, WPA_NONCE_LEN)) {
833		wpa_printf(MSG_INFO, "FT: Failed to generate a new SNonce");
834		return -1;
835	}
836
837	ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, NULL, sm->pmk_r0_name,
838				    NULL, 0, target_ap, NULL, 0, mdie);
839	if (ft_ies) {
840		sm->over_the_ds_in_progress = 1;
841		os_memcpy(sm->target_ap, target_ap, ETH_ALEN);
842		wpa_sm_send_ft_action(sm, 1, target_ap, ft_ies, ft_ies_len);
843		os_free(ft_ies);
844	}
845
846	return 0;
847}
848
849#endif /* CONFIG_IEEE80211R */
850