xref: /freebsd/contrib/wpa/src/rsn_supp/wpa_ft.c (revision d6b92ffa)
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 
21 int 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  */
58 int 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  */
141 static 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 (!wpa_cipher_valid_group(sm->group_cipher)) {
172 		wpa_printf(MSG_WARNING, "FT: Invalid group cipher (%d)",
173 			   sm->group_cipher);
174 		os_free(buf);
175 		return NULL;
176 	}
177 	RSN_SELECTOR_PUT(pos, wpa_cipher_to_suite(WPA_PROTO_RSN,
178 						  sm->group_cipher));
179 	pos += RSN_SELECTOR_LEN;
180 
181 	/* Pairwise Suite Count */
182 	WPA_PUT_LE16(pos, 1);
183 	pos += 2;
184 
185 	/* Pairwise Suite List */
186 	if (!wpa_cipher_valid_pairwise(sm->pairwise_cipher)) {
187 		wpa_printf(MSG_WARNING, "FT: Invalid pairwise cipher (%d)",
188 			   sm->pairwise_cipher);
189 		os_free(buf);
190 		return NULL;
191 	}
192 	RSN_SELECTOR_PUT(pos, wpa_cipher_to_suite(WPA_PROTO_RSN,
193 						  sm->pairwise_cipher));
194 	pos += RSN_SELECTOR_LEN;
195 
196 	/* Authenticated Key Management Suite Count */
197 	WPA_PUT_LE16(pos, 1);
198 	pos += 2;
199 
200 	/* Authenticated Key Management Suite List */
201 	if (sm->key_mgmt == WPA_KEY_MGMT_FT_IEEE8021X)
202 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_802_1X);
203 	else if (sm->key_mgmt == WPA_KEY_MGMT_FT_PSK)
204 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_PSK);
205 	else if (sm->key_mgmt == WPA_KEY_MGMT_FT_SAE)
206 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_SAE);
207 	else {
208 		wpa_printf(MSG_WARNING, "FT: Invalid key management type (%d)",
209 			   sm->key_mgmt);
210 		os_free(buf);
211 		return NULL;
212 	}
213 	pos += RSN_SELECTOR_LEN;
214 
215 	/* RSN Capabilities */
216 	capab = 0;
217 #ifdef CONFIG_IEEE80211W
218 	if (sm->mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC)
219 		capab |= WPA_CAPABILITY_MFPC;
220 #endif /* CONFIG_IEEE80211W */
221 	WPA_PUT_LE16(pos, capab);
222 	pos += 2;
223 
224 	/* PMKID Count */
225 	WPA_PUT_LE16(pos, 1);
226 	pos += 2;
227 
228 	/* PMKID List [PMKR0Name/PMKR1Name] */
229 	os_memcpy(pos, pmk_name, WPA_PMK_NAME_LEN);
230 	pos += WPA_PMK_NAME_LEN;
231 
232 #ifdef CONFIG_IEEE80211W
233 	if (sm->mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC) {
234 		/* Management Group Cipher Suite */
235 		RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_AES_128_CMAC);
236 		pos += RSN_SELECTOR_LEN;
237 	}
238 #endif /* CONFIG_IEEE80211W */
239 
240 	rsnie->len = (pos - (u8 *) rsnie) - 2;
241 
242 	/* MDIE */
243 	*pos++ = WLAN_EID_MOBILITY_DOMAIN;
244 	*pos++ = sizeof(*mdie);
245 	mdie = (struct rsn_mdie *) pos;
246 	pos += sizeof(*mdie);
247 	os_memcpy(mdie->mobility_domain, sm->mobility_domain,
248 		  MOBILITY_DOMAIN_ID_LEN);
249 	mdie->ft_capab = ap_mdie && ap_mdie[1] >= 3 ? ap_mdie[4] :
250 		sm->mdie_ft_capab;
251 
252 	/* FTIE[SNonce, [R1KH-ID,] R0KH-ID ] */
253 	ftie_pos = pos;
254 	*pos++ = WLAN_EID_FAST_BSS_TRANSITION;
255 	ftie_len = pos++;
256 	ftie = (struct rsn_ftie *) pos;
257 	pos += sizeof(*ftie);
258 	os_memcpy(ftie->snonce, sm->snonce, WPA_NONCE_LEN);
259 	if (anonce)
260 		os_memcpy(ftie->anonce, anonce, WPA_NONCE_LEN);
261 	if (kck) {
262 		/* R1KH-ID sub-element in third FT message */
263 		*pos++ = FTIE_SUBELEM_R1KH_ID;
264 		*pos++ = FT_R1KH_ID_LEN;
265 		os_memcpy(pos, sm->r1kh_id, FT_R1KH_ID_LEN);
266 		pos += FT_R1KH_ID_LEN;
267 	}
268 	/* R0KH-ID sub-element */
269 	*pos++ = FTIE_SUBELEM_R0KH_ID;
270 	*pos++ = sm->r0kh_id_len;
271 	os_memcpy(pos, sm->r0kh_id, sm->r0kh_id_len);
272 	pos += sm->r0kh_id_len;
273 	*ftie_len = pos - ftie_len - 1;
274 
275 	if (ric_ies) {
276 		/* RIC Request */
277 		os_memcpy(pos, ric_ies, ric_ies_len);
278 		pos += ric_ies_len;
279 	}
280 
281 	if (kck) {
282 		/*
283 		 * IEEE Std 802.11r-2008, 11A.8.4
284 		 * MIC shall be calculated over:
285 		 * non-AP STA MAC address
286 		 * Target AP MAC address
287 		 * Transaction seq number (5 for ReassocReq, 3 otherwise)
288 		 * RSN IE
289 		 * MDIE
290 		 * FTIE (with MIC field set to 0)
291 		 * RIC-Request (if present)
292 		 */
293 		/* Information element count */
294 		ftie->mic_control[1] = 3 + ieee802_11_ie_count(ric_ies,
295 							       ric_ies_len);
296 		if (wpa_ft_mic(kck, kck_len, sm->own_addr, target_ap, 5,
297 			       ((u8 *) mdie) - 2, 2 + sizeof(*mdie),
298 			       ftie_pos, 2 + *ftie_len,
299 			       (u8 *) rsnie, 2 + rsnie->len, ric_ies,
300 			       ric_ies_len, ftie->mic) < 0) {
301 			wpa_printf(MSG_INFO, "FT: Failed to calculate MIC");
302 			os_free(buf);
303 			return NULL;
304 		}
305 	}
306 
307 	*len = pos - buf;
308 
309 	return buf;
310 }
311 
312 
313 static int wpa_ft_install_ptk(struct wpa_sm *sm, const u8 *bssid)
314 {
315 	int keylen;
316 	enum wpa_alg alg;
317 	u8 null_rsc[6] = { 0, 0, 0, 0, 0, 0 };
318 
319 	wpa_printf(MSG_DEBUG, "FT: Installing PTK to the driver.");
320 
321 	if (!wpa_cipher_valid_pairwise(sm->pairwise_cipher)) {
322 		wpa_printf(MSG_WARNING, "FT: Unsupported pairwise cipher %d",
323 			   sm->pairwise_cipher);
324 		return -1;
325 	}
326 
327 	alg = wpa_cipher_to_alg(sm->pairwise_cipher);
328 	keylen = wpa_cipher_key_len(sm->pairwise_cipher);
329 
330 	if (wpa_sm_set_key(sm, alg, bssid, 0, 1, null_rsc,
331 			   sizeof(null_rsc), (u8 *) sm->ptk.tk, keylen) < 0) {
332 		wpa_printf(MSG_WARNING, "FT: Failed to set PTK to the driver");
333 		return -1;
334 	}
335 
336 	return 0;
337 }
338 
339 
340 /**
341  * wpa_ft_prepare_auth_request - Generate over-the-air auth request
342  * @sm: Pointer to WPA state machine data from wpa_sm_init()
343  * @mdie: Target AP MDIE
344  * Returns: 0 on success, -1 on failure
345  */
346 int wpa_ft_prepare_auth_request(struct wpa_sm *sm, const u8 *mdie)
347 {
348 	u8 *ft_ies;
349 	size_t ft_ies_len;
350 
351 	/* Generate a new SNonce */
352 	if (random_get_bytes(sm->snonce, WPA_NONCE_LEN)) {
353 		wpa_printf(MSG_INFO, "FT: Failed to generate a new SNonce");
354 		return -1;
355 	}
356 
357 	ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, NULL, sm->pmk_r0_name,
358 				    NULL, 0, sm->bssid, NULL, 0, mdie);
359 	if (ft_ies) {
360 		wpa_sm_update_ft_ies(sm, sm->mobility_domain,
361 				     ft_ies, ft_ies_len);
362 		os_free(ft_ies);
363 	}
364 
365 	return 0;
366 }
367 
368 
369 int wpa_ft_process_response(struct wpa_sm *sm, const u8 *ies, size_t ies_len,
370 			    int ft_action, const u8 *target_ap,
371 			    const u8 *ric_ies, size_t ric_ies_len)
372 {
373 	u8 *ft_ies;
374 	size_t ft_ies_len;
375 	struct wpa_ft_ies parse;
376 	struct rsn_mdie *mdie;
377 	struct rsn_ftie *ftie;
378 	u8 ptk_name[WPA_PMK_NAME_LEN];
379 	int ret;
380 	const u8 *bssid;
381 
382 	wpa_hexdump(MSG_DEBUG, "FT: Response IEs", ies, ies_len);
383 	wpa_hexdump(MSG_DEBUG, "FT: RIC IEs", ric_ies, ric_ies_len);
384 
385 	if (ft_action) {
386 		if (!sm->over_the_ds_in_progress) {
387 			wpa_printf(MSG_DEBUG, "FT: No over-the-DS in progress "
388 				   "- drop FT Action Response");
389 			return -1;
390 		}
391 
392 		if (os_memcmp(target_ap, sm->target_ap, ETH_ALEN) != 0) {
393 			wpa_printf(MSG_DEBUG, "FT: No over-the-DS in progress "
394 				   "with this Target AP - drop FT Action "
395 				   "Response");
396 			return -1;
397 		}
398 	}
399 
400 	if (!wpa_key_mgmt_ft(sm->key_mgmt)) {
401 		wpa_printf(MSG_DEBUG, "FT: Reject FT IEs since FT is not "
402 			   "enabled for this connection");
403 		return -1;
404 	}
405 
406 	if (wpa_ft_parse_ies(ies, ies_len, &parse) < 0) {
407 		wpa_printf(MSG_DEBUG, "FT: Failed to parse IEs");
408 		return -1;
409 	}
410 
411 	mdie = (struct rsn_mdie *) parse.mdie;
412 	if (mdie == NULL || parse.mdie_len < sizeof(*mdie) ||
413 	    os_memcmp(mdie->mobility_domain, sm->mobility_domain,
414 		      MOBILITY_DOMAIN_ID_LEN) != 0) {
415 		wpa_printf(MSG_DEBUG, "FT: Invalid MDIE");
416 		return -1;
417 	}
418 
419 	ftie = (struct rsn_ftie *) parse.ftie;
420 	if (ftie == NULL || parse.ftie_len < sizeof(*ftie)) {
421 		wpa_printf(MSG_DEBUG, "FT: Invalid FTIE");
422 		return -1;
423 	}
424 
425 	if (os_memcmp(ftie->snonce, sm->snonce, WPA_NONCE_LEN) != 0) {
426 		wpa_printf(MSG_DEBUG, "FT: SNonce mismatch in FTIE");
427 		wpa_hexdump(MSG_DEBUG, "FT: Received SNonce",
428 			    ftie->snonce, WPA_NONCE_LEN);
429 		wpa_hexdump(MSG_DEBUG, "FT: Expected SNonce",
430 			    sm->snonce, WPA_NONCE_LEN);
431 		return -1;
432 	}
433 
434 	if (parse.r0kh_id == NULL) {
435 		wpa_printf(MSG_DEBUG, "FT: No R0KH-ID subelem in FTIE");
436 		return -1;
437 	}
438 
439 	if (parse.r0kh_id_len != sm->r0kh_id_len ||
440 	    os_memcmp_const(parse.r0kh_id, sm->r0kh_id, parse.r0kh_id_len) != 0)
441 	{
442 		wpa_printf(MSG_DEBUG, "FT: R0KH-ID in FTIE did not match with "
443 			   "the current R0KH-ID");
444 		wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID in FTIE",
445 			    parse.r0kh_id, parse.r0kh_id_len);
446 		wpa_hexdump(MSG_DEBUG, "FT: The current R0KH-ID",
447 			    sm->r0kh_id, sm->r0kh_id_len);
448 		return -1;
449 	}
450 
451 	if (parse.r1kh_id == NULL) {
452 		wpa_printf(MSG_DEBUG, "FT: No R1KH-ID subelem in FTIE");
453 		return -1;
454 	}
455 
456 	if (parse.rsn_pmkid == NULL ||
457 	    os_memcmp_const(parse.rsn_pmkid, sm->pmk_r0_name, WPA_PMK_NAME_LEN))
458 	{
459 		wpa_printf(MSG_DEBUG, "FT: No matching PMKR0Name (PMKID) in "
460 			   "RSNIE");
461 		return -1;
462 	}
463 
464 	os_memcpy(sm->r1kh_id, parse.r1kh_id, FT_R1KH_ID_LEN);
465 	wpa_hexdump(MSG_DEBUG, "FT: R1KH-ID", sm->r1kh_id, FT_R1KH_ID_LEN);
466 	wpa_hexdump(MSG_DEBUG, "FT: SNonce", sm->snonce, WPA_NONCE_LEN);
467 	wpa_hexdump(MSG_DEBUG, "FT: ANonce", ftie->anonce, WPA_NONCE_LEN);
468 	os_memcpy(sm->anonce, ftie->anonce, WPA_NONCE_LEN);
469 	wpa_derive_pmk_r1(sm->pmk_r0, sm->pmk_r0_name, sm->r1kh_id,
470 			  sm->own_addr, sm->pmk_r1, sm->pmk_r1_name);
471 	wpa_hexdump_key(MSG_DEBUG, "FT: PMK-R1", sm->pmk_r1, PMK_LEN);
472 	wpa_hexdump(MSG_DEBUG, "FT: PMKR1Name",
473 		    sm->pmk_r1_name, WPA_PMK_NAME_LEN);
474 
475 	bssid = target_ap;
476 	if (wpa_pmk_r1_to_ptk(sm->pmk_r1, sm->snonce, ftie->anonce,
477 			      sm->own_addr, bssid, sm->pmk_r1_name, &sm->ptk,
478 			      ptk_name, sm->key_mgmt, sm->pairwise_cipher) < 0)
479 		return -1;
480 
481 	ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, ftie->anonce,
482 				    sm->pmk_r1_name,
483 				    sm->ptk.kck, sm->ptk.kck_len, bssid,
484 				    ric_ies, ric_ies_len,
485 				    parse.mdie ? parse.mdie - 2 : NULL);
486 	if (ft_ies) {
487 		wpa_sm_update_ft_ies(sm, sm->mobility_domain,
488 				     ft_ies, ft_ies_len);
489 		os_free(ft_ies);
490 	}
491 
492 	wpa_sm_mark_authenticated(sm, bssid);
493 	ret = wpa_ft_install_ptk(sm, bssid);
494 	if (ret) {
495 		/*
496 		 * Some drivers do not support key configuration when we are
497 		 * not associated with the target AP. Work around this by
498 		 * trying again after the following reassociation gets
499 		 * completed.
500 		 */
501 		wpa_printf(MSG_DEBUG, "FT: Failed to set PTK prior to "
502 			   "association - try again after reassociation");
503 		sm->set_ptk_after_assoc = 1;
504 	} else
505 		sm->set_ptk_after_assoc = 0;
506 
507 	sm->ft_completed = 1;
508 	if (ft_action) {
509 		/*
510 		 * The caller is expected trigger re-association with the
511 		 * Target AP.
512 		 */
513 		os_memcpy(sm->bssid, target_ap, ETH_ALEN);
514 	}
515 
516 	return 0;
517 }
518 
519 
520 int wpa_ft_is_completed(struct wpa_sm *sm)
521 {
522 	if (sm == NULL)
523 		return 0;
524 
525 	if (!wpa_key_mgmt_ft(sm->key_mgmt))
526 		return 0;
527 
528 	return sm->ft_completed;
529 }
530 
531 
532 void wpa_reset_ft_completed(struct wpa_sm *sm)
533 {
534 	if (sm != NULL)
535 		sm->ft_completed = 0;
536 }
537 
538 
539 static int wpa_ft_process_gtk_subelem(struct wpa_sm *sm, const u8 *gtk_elem,
540 				      size_t gtk_elem_len)
541 {
542 	u8 gtk[32];
543 	int keyidx;
544 	enum wpa_alg alg;
545 	size_t gtk_len, keylen, rsc_len;
546 
547 	if (gtk_elem == NULL) {
548 		wpa_printf(MSG_DEBUG, "FT: No GTK included in FTIE");
549 		return 0;
550 	}
551 
552 	wpa_hexdump_key(MSG_DEBUG, "FT: Received GTK in Reassoc Resp",
553 			gtk_elem, gtk_elem_len);
554 
555 	if (gtk_elem_len < 11 + 24 || (gtk_elem_len - 11) % 8 ||
556 	    gtk_elem_len - 19 > sizeof(gtk)) {
557 		wpa_printf(MSG_DEBUG, "FT: Invalid GTK sub-elem "
558 			   "length %lu", (unsigned long) gtk_elem_len);
559 		return -1;
560 	}
561 	gtk_len = gtk_elem_len - 19;
562 	if (aes_unwrap(sm->ptk.kek, sm->ptk.kek_len, gtk_len / 8, gtk_elem + 11,
563 		       gtk)) {
564 		wpa_printf(MSG_WARNING, "FT: AES unwrap failed - could not "
565 			   "decrypt GTK");
566 		return -1;
567 	}
568 
569 	keylen = wpa_cipher_key_len(sm->group_cipher);
570 	rsc_len = wpa_cipher_rsc_len(sm->group_cipher);
571 	alg = wpa_cipher_to_alg(sm->group_cipher);
572 	if (alg == WPA_ALG_NONE) {
573 		wpa_printf(MSG_WARNING, "WPA: Unsupported Group Cipher %d",
574 			   sm->group_cipher);
575 		return -1;
576 	}
577 
578 	if (gtk_len < keylen) {
579 		wpa_printf(MSG_DEBUG, "FT: Too short GTK in FTIE");
580 		return -1;
581 	}
582 
583 	/* Key Info[2] | Key Length[1] | RSC[8] | Key[5..32]. */
584 
585 	keyidx = WPA_GET_LE16(gtk_elem) & 0x03;
586 
587 	if (gtk_elem[2] != keylen) {
588 		wpa_printf(MSG_DEBUG, "FT: GTK length mismatch: received %d "
589 			   "negotiated %lu",
590 			   gtk_elem[2], (unsigned long) keylen);
591 		return -1;
592 	}
593 
594 	wpa_hexdump_key(MSG_DEBUG, "FT: GTK from Reassoc Resp", gtk, keylen);
595 	if (sm->group_cipher == WPA_CIPHER_TKIP) {
596 		/* Swap Tx/Rx keys for Michael MIC */
597 		u8 tmp[8];
598 		os_memcpy(tmp, gtk + 16, 8);
599 		os_memcpy(gtk + 16, gtk + 24, 8);
600 		os_memcpy(gtk + 24, tmp, 8);
601 	}
602 	if (wpa_sm_set_key(sm, alg, broadcast_ether_addr, keyidx, 0,
603 			   gtk_elem + 3, rsc_len, gtk, keylen) < 0) {
604 		wpa_printf(MSG_WARNING, "WPA: Failed to set GTK to the "
605 			   "driver.");
606 		return -1;
607 	}
608 
609 	return 0;
610 }
611 
612 
613 #ifdef CONFIG_IEEE80211W
614 static int wpa_ft_process_igtk_subelem(struct wpa_sm *sm, const u8 *igtk_elem,
615 				       size_t igtk_elem_len)
616 {
617 	u8 igtk[WPA_IGTK_LEN];
618 	u16 keyidx;
619 
620 	if (sm->mgmt_group_cipher != WPA_CIPHER_AES_128_CMAC)
621 		return 0;
622 
623 	if (igtk_elem == NULL) {
624 		wpa_printf(MSG_DEBUG, "FT: No IGTK included in FTIE");
625 		return 0;
626 	}
627 
628 	wpa_hexdump_key(MSG_DEBUG, "FT: Received IGTK in Reassoc Resp",
629 			igtk_elem, igtk_elem_len);
630 
631 	if (igtk_elem_len != 2 + 6 + 1 + WPA_IGTK_LEN + 8) {
632 		wpa_printf(MSG_DEBUG, "FT: Invalid IGTK sub-elem "
633 			   "length %lu", (unsigned long) igtk_elem_len);
634 		return -1;
635 	}
636 	if (igtk_elem[8] != WPA_IGTK_LEN) {
637 		wpa_printf(MSG_DEBUG, "FT: Invalid IGTK sub-elem Key Length "
638 			   "%d", igtk_elem[8]);
639 		return -1;
640 	}
641 
642 	if (aes_unwrap(sm->ptk.kek, sm->ptk.kek_len, WPA_IGTK_LEN / 8,
643 		       igtk_elem + 9, igtk)) {
644 		wpa_printf(MSG_WARNING, "FT: AES unwrap failed - could not "
645 			   "decrypt IGTK");
646 		return -1;
647 	}
648 
649 	/* KeyID[2] | IPN[6] | Key Length[1] | Key[16+8] */
650 
651 	keyidx = WPA_GET_LE16(igtk_elem);
652 
653 	wpa_hexdump_key(MSG_DEBUG, "FT: IGTK from Reassoc Resp", igtk,
654 			WPA_IGTK_LEN);
655 	if (wpa_sm_set_key(sm, WPA_ALG_IGTK, broadcast_ether_addr, keyidx, 0,
656 			   igtk_elem + 2, 6, igtk, WPA_IGTK_LEN) < 0) {
657 		wpa_printf(MSG_WARNING, "WPA: Failed to set IGTK to the "
658 			   "driver.");
659 		return -1;
660 	}
661 
662 	return 0;
663 }
664 #endif /* CONFIG_IEEE80211W */
665 
666 
667 int wpa_ft_validate_reassoc_resp(struct wpa_sm *sm, const u8 *ies,
668 				 size_t ies_len, const u8 *src_addr)
669 {
670 	struct wpa_ft_ies parse;
671 	struct rsn_mdie *mdie;
672 	struct rsn_ftie *ftie;
673 	unsigned int count;
674 	u8 mic[WPA_EAPOL_KEY_MIC_MAX_LEN];
675 
676 	wpa_hexdump(MSG_DEBUG, "FT: Response IEs", ies, ies_len);
677 
678 	if (!wpa_key_mgmt_ft(sm->key_mgmt)) {
679 		wpa_printf(MSG_DEBUG, "FT: Reject FT IEs since FT is not "
680 			   "enabled for this connection");
681 		return -1;
682 	}
683 
684 	if (wpa_ft_parse_ies(ies, ies_len, &parse) < 0) {
685 		wpa_printf(MSG_DEBUG, "FT: Failed to parse IEs");
686 		return -1;
687 	}
688 
689 	mdie = (struct rsn_mdie *) parse.mdie;
690 	if (mdie == NULL || parse.mdie_len < sizeof(*mdie) ||
691 	    os_memcmp(mdie->mobility_domain, sm->mobility_domain,
692 		      MOBILITY_DOMAIN_ID_LEN) != 0) {
693 		wpa_printf(MSG_DEBUG, "FT: Invalid MDIE");
694 		return -1;
695 	}
696 
697 	ftie = (struct rsn_ftie *) parse.ftie;
698 	if (ftie == NULL || parse.ftie_len < sizeof(*ftie)) {
699 		wpa_printf(MSG_DEBUG, "FT: Invalid FTIE");
700 		return -1;
701 	}
702 
703 	if (os_memcmp(ftie->snonce, sm->snonce, WPA_NONCE_LEN) != 0) {
704 		wpa_printf(MSG_DEBUG, "FT: SNonce mismatch in FTIE");
705 		wpa_hexdump(MSG_DEBUG, "FT: Received SNonce",
706 			    ftie->snonce, WPA_NONCE_LEN);
707 		wpa_hexdump(MSG_DEBUG, "FT: Expected SNonce",
708 			    sm->snonce, WPA_NONCE_LEN);
709 		return -1;
710 	}
711 
712 	if (os_memcmp(ftie->anonce, sm->anonce, WPA_NONCE_LEN) != 0) {
713 		wpa_printf(MSG_DEBUG, "FT: ANonce mismatch in FTIE");
714 		wpa_hexdump(MSG_DEBUG, "FT: Received ANonce",
715 			    ftie->anonce, WPA_NONCE_LEN);
716 		wpa_hexdump(MSG_DEBUG, "FT: Expected ANonce",
717 			    sm->anonce, WPA_NONCE_LEN);
718 		return -1;
719 	}
720 
721 	if (parse.r0kh_id == NULL) {
722 		wpa_printf(MSG_DEBUG, "FT: No R0KH-ID subelem in FTIE");
723 		return -1;
724 	}
725 
726 	if (parse.r0kh_id_len != sm->r0kh_id_len ||
727 	    os_memcmp_const(parse.r0kh_id, sm->r0kh_id, parse.r0kh_id_len) != 0)
728 	{
729 		wpa_printf(MSG_DEBUG, "FT: R0KH-ID in FTIE did not match with "
730 			   "the current R0KH-ID");
731 		wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID in FTIE",
732 			    parse.r0kh_id, parse.r0kh_id_len);
733 		wpa_hexdump(MSG_DEBUG, "FT: The current R0KH-ID",
734 			    sm->r0kh_id, sm->r0kh_id_len);
735 		return -1;
736 	}
737 
738 	if (parse.r1kh_id == NULL) {
739 		wpa_printf(MSG_DEBUG, "FT: No R1KH-ID subelem in FTIE");
740 		return -1;
741 	}
742 
743 	if (os_memcmp_const(parse.r1kh_id, sm->r1kh_id, FT_R1KH_ID_LEN) != 0) {
744 		wpa_printf(MSG_DEBUG, "FT: Unknown R1KH-ID used in "
745 			   "ReassocResp");
746 		return -1;
747 	}
748 
749 	if (parse.rsn_pmkid == NULL ||
750 	    os_memcmp_const(parse.rsn_pmkid, sm->pmk_r1_name, WPA_PMK_NAME_LEN))
751 	{
752 		wpa_printf(MSG_DEBUG, "FT: No matching PMKR1Name (PMKID) in "
753 			   "RSNIE (pmkid=%d)", !!parse.rsn_pmkid);
754 		return -1;
755 	}
756 
757 	count = 3;
758 	if (parse.ric)
759 		count += ieee802_11_ie_count(parse.ric, parse.ric_len);
760 	if (ftie->mic_control[1] != count) {
761 		wpa_printf(MSG_DEBUG, "FT: Unexpected IE count in MIC "
762 			   "Control: received %u expected %u",
763 			   ftie->mic_control[1], count);
764 		return -1;
765 	}
766 
767 	if (wpa_ft_mic(sm->ptk.kck, sm->ptk.kck_len, sm->own_addr, src_addr, 6,
768 		       parse.mdie - 2, parse.mdie_len + 2,
769 		       parse.ftie - 2, parse.ftie_len + 2,
770 		       parse.rsn - 2, parse.rsn_len + 2,
771 		       parse.ric, parse.ric_len,
772 		       mic) < 0) {
773 		wpa_printf(MSG_DEBUG, "FT: Failed to calculate MIC");
774 		return -1;
775 	}
776 
777 	if (os_memcmp_const(mic, ftie->mic, 16) != 0) {
778 		wpa_printf(MSG_DEBUG, "FT: Invalid MIC in FTIE");
779 		wpa_hexdump(MSG_MSGDUMP, "FT: Received MIC", ftie->mic, 16);
780 		wpa_hexdump(MSG_MSGDUMP, "FT: Calculated MIC", mic, 16);
781 		return -1;
782 	}
783 
784 	if (wpa_ft_process_gtk_subelem(sm, parse.gtk, parse.gtk_len) < 0)
785 		return -1;
786 
787 #ifdef CONFIG_IEEE80211W
788 	if (wpa_ft_process_igtk_subelem(sm, parse.igtk, parse.igtk_len) < 0)
789 		return -1;
790 #endif /* CONFIG_IEEE80211W */
791 
792 	if (sm->set_ptk_after_assoc) {
793 		wpa_printf(MSG_DEBUG, "FT: Try to set PTK again now that we "
794 			   "are associated");
795 		if (wpa_ft_install_ptk(sm, src_addr) < 0)
796 			return -1;
797 		sm->set_ptk_after_assoc = 0;
798 	}
799 
800 	if (parse.ric) {
801 		wpa_hexdump(MSG_MSGDUMP, "FT: RIC Response",
802 			    parse.ric, parse.ric_len);
803 		/* TODO: parse response and inform driver about results when
804 		 * using wpa_supplicant SME */
805 	}
806 
807 	wpa_printf(MSG_DEBUG, "FT: Completed successfully");
808 
809 	return 0;
810 }
811 
812 
813 /**
814  * wpa_ft_start_over_ds - Generate over-the-DS auth request
815  * @sm: Pointer to WPA state machine data from wpa_sm_init()
816  * @target_ap: Target AP Address
817  * @mdie: Mobility Domain IE from the target AP
818  * Returns: 0 on success, -1 on failure
819  */
820 int wpa_ft_start_over_ds(struct wpa_sm *sm, const u8 *target_ap,
821 			 const u8 *mdie)
822 {
823 	u8 *ft_ies;
824 	size_t ft_ies_len;
825 
826 	wpa_printf(MSG_DEBUG, "FT: Request over-the-DS with " MACSTR,
827 		   MAC2STR(target_ap));
828 
829 	/* Generate a new SNonce */
830 	if (random_get_bytes(sm->snonce, WPA_NONCE_LEN)) {
831 		wpa_printf(MSG_INFO, "FT: Failed to generate a new SNonce");
832 		return -1;
833 	}
834 
835 	ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, NULL, sm->pmk_r0_name,
836 				    NULL, 0, target_ap, NULL, 0, mdie);
837 	if (ft_ies) {
838 		sm->over_the_ds_in_progress = 1;
839 		os_memcpy(sm->target_ap, target_ap, ETH_ALEN);
840 		wpa_sm_send_ft_action(sm, 1, target_ap, ft_ies, ft_ies_len);
841 		os_free(ft_ies);
842 	}
843 
844 	return 0;
845 }
846 
847 #endif /* CONFIG_IEEE80211R */
848