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1 /*
2  * WPA Supplicant - IEEE 802.11r - Fast BSS Transition
3  * Copyright (c) 2006-2007, Jouni Malinen <j@w1.fi>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  *
9  * Alternatively, this software may be distributed under the terms of BSD
10  * license.
11  *
12  * See README and COPYING for more details.
13  */
14 
15 #include "includes.h"
16 
17 #include "common.h"
18 #include "wpa.h"
19 #include "wpa_i.h"
20 #include "wpa_ie.h"
21 #include "aes_wrap.h"
22 #include "ieee802_11_defs.h"
23 
24 #ifdef CONFIG_IEEE80211R
25 
wpa_derive_ptk_ft(struct wpa_sm * sm,const unsigned char * src_addr,const struct wpa_eapol_key * key,struct wpa_ptk * ptk,size_t ptk_len)26 int wpa_derive_ptk_ft(struct wpa_sm *sm, const unsigned char *src_addr,
27 		      const struct wpa_eapol_key *key,
28 		      struct wpa_ptk *ptk, size_t ptk_len)
29 {
30 	u8 pmk_r1_name[WPA_PMK_NAME_LEN];
31 	u8 ptk_name[WPA_PMK_NAME_LEN];
32 	const u8 *anonce = key->key_nonce;
33 
34 	if (sm->xxkey_len == 0) {
35 		wpa_printf(MSG_DEBUG, "FT: XXKey not available for key "
36 			   "derivation");
37 		return -1;
38 	}
39 
40 	wpa_derive_pmk_r0(sm->xxkey, sm->xxkey_len, sm->ssid,
41 			  sm->ssid_len, sm->mobility_domain,
42 			  sm->r0kh_id, sm->r0kh_id_len, sm->own_addr,
43 			  sm->pmk_r0, sm->pmk_r0_name);
44 	wpa_hexdump_key(MSG_DEBUG, "FT: PMK-R0", sm->pmk_r0, PMK_LEN);
45 	wpa_hexdump(MSG_DEBUG, "FT: PMKR0Name",
46 		    sm->pmk_r0_name, WPA_PMK_NAME_LEN);
47 	wpa_derive_pmk_r1(sm->pmk_r0, sm->pmk_r0_name, sm->r1kh_id,
48 			  sm->own_addr, sm->pmk_r1, pmk_r1_name);
49 	wpa_hexdump_key(MSG_DEBUG, "FT: PMK-R1", sm->pmk_r1, PMK_LEN);
50 	wpa_hexdump(MSG_DEBUG, "FT: PMKR1Name", pmk_r1_name, WPA_PMK_NAME_LEN);
51 	wpa_pmk_r1_to_ptk(sm->pmk_r1, sm->snonce, anonce, sm->own_addr,
52 			  sm->bssid, pmk_r1_name,
53 			  (u8 *) ptk, ptk_len, ptk_name);
54 	wpa_hexdump_key(MSG_DEBUG, "FT: PTK", (u8 *) ptk, ptk_len);
55 	wpa_hexdump(MSG_DEBUG, "FT: PTKName", ptk_name, WPA_PMK_NAME_LEN);
56 
57 	return 0;
58 }
59 
60 
61 /**
62  * wpa_sm_set_ft_params - Set FT (IEEE 802.11r) parameters
63  * @sm: Pointer to WPA state machine data from wpa_sm_init()
64  * @mobility_domain: Mobility domain identifier (2 octets)
65  * @r0kh_id: PMK-R0 key holder identity (1-48 octets)
66  * @r0kh_id_len: R0KH-ID length (1-48)
67  * @r1kh_id: PMK-R1 key holder identity (16 octets)
68  * Returns: 0 on success, -1 on failure
69  */
wpa_sm_set_ft_params(struct wpa_sm * sm,const u8 * mobility_domain,const u8 * r0kh_id,size_t r0kh_id_len,const u8 * r1kh_id)70 int wpa_sm_set_ft_params(struct wpa_sm *sm, const u8 *mobility_domain,
71 			 const u8 *r0kh_id, size_t r0kh_id_len,
72 			 const u8 *r1kh_id)
73 {
74 	if (sm && mobility_domain) {
75 		wpa_hexdump(MSG_DEBUG, "FT: Mobility domain",
76 			    mobility_domain, MOBILITY_DOMAIN_ID_LEN);
77 		os_memcpy(sm->mobility_domain, mobility_domain,
78 			  MOBILITY_DOMAIN_ID_LEN);
79 	} else if (sm)
80 		os_memset(sm->mobility_domain, 0, MOBILITY_DOMAIN_ID_LEN);
81 
82 	if (sm && r0kh_id) {
83 		if (r0kh_id_len > FT_R0KH_ID_MAX_LEN)
84 			return -1;
85 		wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID", r0kh_id, r0kh_id_len);
86 		os_memcpy(sm->r0kh_id, r0kh_id, r0kh_id_len);
87 		sm->r0kh_id_len = r0kh_id_len;
88 	} else if (sm) {
89 		/* FIX: When should R0KH-ID be cleared? We need to keep the
90 		 * old R0KH-ID in order to be able to use this during FT. */
91 		/*
92 		 * os_memset(sm->r0kh_id, 0, FT_R0KH_ID_LEN);
93 		 * sm->r0kh_id_len = 0;
94 		 */
95 	}
96 
97 	if (sm && r1kh_id) {
98 		wpa_hexdump(MSG_DEBUG, "FT: R1KH-ID", r1kh_id, FT_R1KH_ID_LEN);
99 		os_memcpy(sm->r1kh_id, r1kh_id, FT_R1KH_ID_LEN);
100 	} else if (sm)
101 		os_memset(sm->r1kh_id, 0, FT_R1KH_ID_LEN);
102 
103 	return 0;
104 }
105 
106 
107 /**
108  * wpa_ft_gen_req_ies - Generate FT (IEEE 802.11r) IEs for Auth Request
109  * @sm: Pointer to WPA state machine data from wpa_sm_init()
110  * @len: Buffer for returning the length of the IEs
111  * @anonce: ANonce or %NULL if not yet available
112  * @pmk_name: PMKR0Name or PMKR1Name to be added into the RSN IE PMKID List
113  * @kck: 128-bit KCK for MIC or %NULL if no MIC is used
114  * @target_ap: Target AP address
115  * Returns: Pointer to buffer with IEs or %NULL on failure
116  *
117  * Caller is responsible for freeing the returned buffer with os_free();
118  */
wpa_ft_gen_req_ies(struct wpa_sm * sm,size_t * len,const u8 * anonce,const u8 * pmk_name,const u8 * kck,const u8 * target_ap)119 static u8 * wpa_ft_gen_req_ies(struct wpa_sm *sm, size_t *len,
120 			       const u8 *anonce, const u8 *pmk_name,
121 			       const u8 *kck, const u8 *target_ap)
122 {
123 	size_t buf_len;
124 	u8 *buf, *pos, *ftie_len, *ftie_pos;
125 	struct rsn_mdie *mdie;
126 	struct rsn_ftie *ftie;
127 	struct rsn_ie_hdr *rsnie;
128 	u16 capab;
129 
130 	sm->ft_completed = 0;
131 
132 	buf_len = 2 + sizeof(struct rsn_mdie) + 2 + sizeof(struct rsn_ftie) +
133 		2 + sm->r0kh_id_len + 100;
134 	buf = os_zalloc(buf_len);
135 	if (buf == NULL)
136 		return NULL;
137 	pos = buf;
138 
139 	/* RSNIE[PMKR0Name] */
140 	rsnie = (struct rsn_ie_hdr *) pos;
141 	rsnie->elem_id = WLAN_EID_RSN;
142 	WPA_PUT_LE16(rsnie->version, RSN_VERSION);
143 	pos = (u8 *) (rsnie + 1);
144 
145 	/* Group Suite Selector */
146 	if (sm->group_cipher == WPA_CIPHER_CCMP)
147 		RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_CCMP);
148 	else if (sm->group_cipher == WPA_CIPHER_TKIP)
149 		RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_TKIP);
150 	else {
151 		wpa_printf(MSG_WARNING, "FT: Invalid group cipher (%d)",
152 			   sm->group_cipher);
153 		os_free(buf);
154 		return NULL;
155 	}
156 	pos += RSN_SELECTOR_LEN;
157 
158 	/* Pairwise Suite Count */
159 	WPA_PUT_LE16(pos, 1);
160 	pos += 2;
161 
162 	/* Pairwise Suite List */
163 	if (sm->pairwise_cipher == WPA_CIPHER_CCMP)
164 		RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_CCMP);
165 	else if (sm->pairwise_cipher == WPA_CIPHER_TKIP)
166 		RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_TKIP);
167 	else {
168 		wpa_printf(MSG_WARNING, "FT: Invalid pairwise cipher (%d)",
169 			   sm->pairwise_cipher);
170 		os_free(buf);
171 		return NULL;
172 	}
173 	pos += RSN_SELECTOR_LEN;
174 
175 	/* Authenticated Key Management Suite Count */
176 	WPA_PUT_LE16(pos, 1);
177 	pos += 2;
178 
179 	/* Authenticated Key Management Suite List */
180 	if (sm->key_mgmt == WPA_KEY_MGMT_FT_IEEE8021X)
181 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_802_1X);
182 	else if (sm->key_mgmt == WPA_KEY_MGMT_FT_PSK)
183 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_PSK);
184 	else {
185 		wpa_printf(MSG_WARNING, "FT: Invalid key management type (%d)",
186 			   sm->key_mgmt);
187 		os_free(buf);
188 		return NULL;
189 	}
190 	pos += RSN_SELECTOR_LEN;
191 
192 	/* RSN Capabilities */
193 	capab = 0;
194 #ifdef CONFIG_IEEE80211W
195 	if (sm->mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC)
196 		capab |= WPA_CAPABILITY_MFPC;
197 #endif /* CONFIG_IEEE80211W */
198 	WPA_PUT_LE16(pos, capab);
199 	pos += 2;
200 
201 	/* PMKID Count */
202 	WPA_PUT_LE16(pos, 1);
203 	pos += 2;
204 
205 	/* PMKID List [PMKR0Name/PMKR1Name] */
206 	os_memcpy(pos, pmk_name, WPA_PMK_NAME_LEN);
207 	pos += WPA_PMK_NAME_LEN;
208 
209 #ifdef CONFIG_IEEE80211W
210 	if (sm->mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC) {
211 		/* Management Group Cipher Suite */
212 		RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_AES_128_CMAC);
213 		pos += RSN_SELECTOR_LEN;
214 	}
215 #endif /* CONFIG_IEEE80211W */
216 
217 	rsnie->len = (pos - (u8 *) rsnie) - 2;
218 
219 	/* MDIE */
220 	*pos++ = WLAN_EID_MOBILITY_DOMAIN;
221 	*pos++ = sizeof(*mdie);
222 	mdie = (struct rsn_mdie *) pos;
223 	pos += sizeof(*mdie);
224 	os_memcpy(mdie->mobility_domain, sm->mobility_domain,
225 		  MOBILITY_DOMAIN_ID_LEN);
226 	mdie->ft_capab = 0; /* FIX: copy from the target AP's MDIE */
227 
228 	/* FTIE[SNonce, R0KH-ID] */
229 	ftie_pos = pos;
230 	*pos++ = WLAN_EID_FAST_BSS_TRANSITION;
231 	ftie_len = pos++;
232 	ftie = (struct rsn_ftie *) pos;
233 	pos += sizeof(*ftie);
234 	os_memcpy(ftie->snonce, sm->snonce, WPA_NONCE_LEN);
235 	if (anonce)
236 		os_memcpy(ftie->anonce, anonce, WPA_NONCE_LEN);
237 	/* R0KH-ID sub-element */
238 	*pos++ = FTIE_SUBELEM_R0KH_ID;
239 	*pos++ = sm->r0kh_id_len;
240 	os_memcpy(pos, sm->r0kh_id, sm->r0kh_id_len);
241 	pos += sm->r0kh_id_len;
242 	*ftie_len = pos - ftie_len - 1;
243 
244 	if (kck) {
245 		/*
246 		 * IEEE Std 802.11r-2008, 11A.8.4
247 		 * MIC shall be calculated over:
248 		 * non-AP STA MAC address
249 		 * Target AP MAC address
250 		 * Transaction seq number (5 for ReassocReq, 3 otherwise)
251 		 * RSN IE
252 		 * MDIE
253 		 * FTIE (with MIC field set to 0)
254 		 * RIC-Request (if present)
255 		 */
256 		ftie->mic_control[1] = 3; /* Information element count */
257 		if (wpa_ft_mic(kck, sm->own_addr, target_ap, 5,
258 			       ((u8 *) mdie) - 2, 2 + sizeof(*mdie),
259 			       ftie_pos, 2 + *ftie_len,
260 			       (u8 *) rsnie, 2 + rsnie->len, NULL, 0,
261 			       ftie->mic) < 0) {
262 			wpa_printf(MSG_INFO, "FT: Failed to calculate MIC");
263 			os_free(buf);
264 			return NULL;
265 		}
266 	}
267 
268 	*len = pos - buf;
269 
270 	return buf;
271 }
272 
273 
274 struct wpa_ft_ies {
275 	const u8 *mdie;
276 	size_t mdie_len;
277 	const u8 *ftie;
278 	size_t ftie_len;
279 	const u8 *r1kh_id;
280 	const u8 *gtk;
281 	size_t gtk_len;
282 	const u8 *r0kh_id;
283 	size_t r0kh_id_len;
284 	const u8 *rsn;
285 	size_t rsn_len;
286 	const u8 *rsn_pmkid;
287 	const u8 *tie;
288 	size_t tie_len;
289 	const u8 *igtk;
290 	size_t igtk_len;
291 };
292 
293 
wpa_ft_parse_ftie(const u8 * ie,size_t ie_len,struct wpa_ft_ies * parse)294 static int wpa_ft_parse_ftie(const u8 *ie, size_t ie_len,
295 			     struct wpa_ft_ies *parse)
296 {
297 	const u8 *end, *pos;
298 
299 	parse->ftie = ie;
300 	parse->ftie_len = ie_len;
301 
302 	pos = ie + sizeof(struct rsn_ftie);
303 	end = ie + ie_len;
304 
305 	while (pos + 2 <= end && pos + 2 + pos[1] <= end) {
306 		switch (pos[0]) {
307 		case FTIE_SUBELEM_R1KH_ID:
308 			if (pos[1] != FT_R1KH_ID_LEN) {
309 				wpa_printf(MSG_DEBUG, "FT: Invalid R1KH-ID "
310 					   "length in FTIE: %d", pos[1]);
311 				return -1;
312 			}
313 			parse->r1kh_id = pos + 2;
314 			break;
315 		case FTIE_SUBELEM_GTK:
316 			parse->gtk = pos + 2;
317 			parse->gtk_len = pos[1];
318 			break;
319 		case FTIE_SUBELEM_R0KH_ID:
320 			if (pos[1] < 1 || pos[1] > FT_R0KH_ID_MAX_LEN) {
321 				wpa_printf(MSG_DEBUG, "FT: Invalid R0KH-ID "
322 					   "length in FTIE: %d", pos[1]);
323 				return -1;
324 			}
325 			parse->r0kh_id = pos + 2;
326 			parse->r0kh_id_len = pos[1];
327 			break;
328 #ifdef CONFIG_IEEE80211W
329 		case FTIE_SUBELEM_IGTK:
330 			parse->igtk = pos + 2;
331 			parse->igtk_len = pos[1];
332 			break;
333 #endif /* CONFIG_IEEE80211W */
334 		}
335 
336 		pos += 2 + pos[1];
337 	}
338 
339 	return 0;
340 }
341 
342 
wpa_ft_parse_ies(const u8 * ies,size_t ies_len,struct wpa_ft_ies * parse)343 static int wpa_ft_parse_ies(const u8 *ies, size_t ies_len,
344 			    struct wpa_ft_ies *parse)
345 {
346 	const u8 *end, *pos;
347 	struct wpa_ie_data data;
348 	int ret;
349 
350 	os_memset(parse, 0, sizeof(*parse));
351 	if (ies == NULL)
352 		return 0;
353 
354 	pos = ies;
355 	end = ies + ies_len;
356 	while (pos + 2 <= end && pos + 2 + pos[1] <= end) {
357 		switch (pos[0]) {
358 		case WLAN_EID_RSN:
359 			parse->rsn = pos + 2;
360 			parse->rsn_len = pos[1];
361 			ret = wpa_parse_wpa_ie_rsn(parse->rsn - 2,
362 						   parse->rsn_len + 2,
363 						   &data);
364 			if (ret < 0) {
365 				wpa_printf(MSG_DEBUG, "FT: Failed to parse "
366 					   "RSN IE: %d", ret);
367 				return -1;
368 			}
369 			if (data.num_pmkid == 1 && data.pmkid)
370 				parse->rsn_pmkid = data.pmkid;
371 			break;
372 		case WLAN_EID_MOBILITY_DOMAIN:
373 			parse->mdie = pos + 2;
374 			parse->mdie_len = pos[1];
375 			break;
376 		case WLAN_EID_FAST_BSS_TRANSITION:
377 			if (wpa_ft_parse_ftie(pos + 2, pos[1], parse) < 0)
378 				return -1;
379 			break;
380 		case WLAN_EID_TIMEOUT_INTERVAL:
381 			parse->tie = pos + 2;
382 			parse->tie_len = pos[1];
383 			break;
384 		}
385 
386 		pos += 2 + pos[1];
387 	}
388 
389 	return 0;
390 }
391 
392 
wpa_ft_install_ptk(struct wpa_sm * sm,const u8 * bssid)393 static int wpa_ft_install_ptk(struct wpa_sm *sm, const u8 *bssid)
394 {
395 	int keylen;
396 	wpa_alg alg;
397 	u8 null_rsc[6] = { 0, 0, 0, 0, 0, 0 };
398 
399 	wpa_printf(MSG_DEBUG, "FT: Installing PTK to the driver.");
400 
401 	switch (sm->pairwise_cipher) {
402 	case WPA_CIPHER_CCMP:
403 		alg = WPA_ALG_CCMP;
404 		keylen = 16;
405 		break;
406 	case WPA_CIPHER_TKIP:
407 		alg = WPA_ALG_TKIP;
408 		keylen = 32;
409 		break;
410 	default:
411 		wpa_printf(MSG_WARNING, "FT: Unsupported pairwise cipher %d",
412 			   sm->pairwise_cipher);
413 		return -1;
414 	}
415 
416 	if (wpa_sm_set_key(sm, alg, bssid, 0, 1, null_rsc,
417 			   sizeof(null_rsc), (u8 *) sm->ptk.tk1, keylen) < 0) {
418 		wpa_printf(MSG_WARNING, "FT: Failed to set PTK to the driver");
419 		return -1;
420 	}
421 
422 	return 0;
423 }
424 
425 
426 /**
427  * wpa_ft_prepare_auth_request - Generate over-the-air auth request
428  * @sm: Pointer to WPA state machine data from wpa_sm_init()
429  * Returns: 0 on success, -1 on failure
430  */
wpa_ft_prepare_auth_request(struct wpa_sm * sm)431 int wpa_ft_prepare_auth_request(struct wpa_sm *sm)
432 {
433 	u8 *ft_ies;
434 	size_t ft_ies_len;
435 
436 	/* Generate a new SNonce */
437 	if (os_get_random(sm->snonce, WPA_NONCE_LEN)) {
438 		wpa_printf(MSG_INFO, "FT: Failed to generate a new SNonce");
439 		return -1;
440 	}
441 
442 	ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, NULL, sm->pmk_r0_name,
443 				    NULL, sm->bssid);
444 	if (ft_ies) {
445 		wpa_sm_update_ft_ies(sm, sm->mobility_domain,
446 				     ft_ies, ft_ies_len);
447 		os_free(ft_ies);
448 	}
449 
450 	return 0;
451 }
452 
453 
wpa_ft_process_response(struct wpa_sm * sm,const u8 * ies,size_t ies_len,int ft_action,const u8 * target_ap)454 int wpa_ft_process_response(struct wpa_sm *sm, const u8 *ies, size_t ies_len,
455 			    int ft_action, const u8 *target_ap)
456 {
457 	u8 *ft_ies;
458 	size_t ft_ies_len, ptk_len;
459 	struct wpa_ft_ies parse;
460 	struct rsn_mdie *mdie;
461 	struct rsn_ftie *ftie;
462 	u8 ptk_name[WPA_PMK_NAME_LEN];
463 	int ret;
464 	const u8 *bssid;
465 
466 	wpa_hexdump(MSG_DEBUG, "FT: Response IEs", ies, ies_len);
467 
468 	if (ft_action) {
469 		if (!sm->over_the_ds_in_progress) {
470 			wpa_printf(MSG_DEBUG, "FT: No over-the-DS in progress "
471 				   "- drop FT Action Response");
472 			return -1;
473 		}
474 
475 		if (os_memcmp(target_ap, sm->target_ap, ETH_ALEN) != 0) {
476 			wpa_printf(MSG_DEBUG, "FT: No over-the-DS in progress "
477 				   "with this Target AP - drop FT Action "
478 				   "Response");
479 			return -1;
480 		}
481 	}
482 
483 	if (sm->key_mgmt != WPA_KEY_MGMT_FT_IEEE8021X &&
484 	    sm->key_mgmt != WPA_KEY_MGMT_FT_PSK) {
485 		wpa_printf(MSG_DEBUG, "FT: Reject FT IEs since FT is not "
486 			   "enabled for this connection");
487 		return -1;
488 	}
489 
490 	if (wpa_ft_parse_ies(ies, ies_len, &parse) < 0) {
491 		wpa_printf(MSG_DEBUG, "FT: Failed to parse IEs");
492 		return -1;
493 	}
494 
495 	mdie = (struct rsn_mdie *) parse.mdie;
496 	if (mdie == NULL || parse.mdie_len < sizeof(*mdie) ||
497 	    os_memcmp(mdie->mobility_domain, sm->mobility_domain,
498 		      MOBILITY_DOMAIN_ID_LEN) != 0) {
499 		wpa_printf(MSG_DEBUG, "FT: Invalid MDIE");
500 		return -1;
501 	}
502 
503 	ftie = (struct rsn_ftie *) parse.ftie;
504 	if (ftie == NULL || parse.ftie_len < sizeof(*ftie)) {
505 		wpa_printf(MSG_DEBUG, "FT: Invalid FTIE");
506 		return -1;
507 	}
508 
509 	if (parse.r0kh_id == NULL) {
510 		wpa_printf(MSG_DEBUG, "FT: No R0KH-ID subelem in FTIE");
511 		return -1;
512 	}
513 
514 	if (parse.r0kh_id_len != sm->r0kh_id_len ||
515 	    os_memcmp(parse.r0kh_id, sm->r0kh_id, parse.r0kh_id_len) != 0) {
516 		wpa_printf(MSG_DEBUG, "FT: R0KH-ID in FTIE did not match with "
517 			   "the current R0KH-ID");
518 		wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID in FTIE",
519 			    parse.r0kh_id, parse.r0kh_id_len);
520 		wpa_hexdump(MSG_DEBUG, "FT: The current R0KH-ID",
521 			    sm->r0kh_id, sm->r0kh_id_len);
522 		return -1;
523 	}
524 
525 	if (parse.r1kh_id == NULL) {
526 		wpa_printf(MSG_DEBUG, "FT: No R1KH-ID subelem in FTIE");
527 		return -1;
528 	}
529 
530 	if (parse.rsn_pmkid == NULL ||
531 	    os_memcmp(parse.rsn_pmkid, sm->pmk_r0_name, WPA_PMK_NAME_LEN)) {
532 		wpa_printf(MSG_DEBUG, "FT: No matching PMKR0Name (PMKID) in "
533 			   "RSNIE");
534 		return -1;
535 	}
536 
537 	os_memcpy(sm->r1kh_id, parse.r1kh_id, FT_R1KH_ID_LEN);
538 	wpa_hexdump(MSG_DEBUG, "FT: R1KH-ID", sm->r1kh_id, FT_R1KH_ID_LEN);
539 	wpa_hexdump(MSG_DEBUG, "FT: SNonce", sm->snonce, WPA_NONCE_LEN);
540 	wpa_hexdump(MSG_DEBUG, "FT: ANonce", ftie->anonce, WPA_NONCE_LEN);
541 	wpa_derive_pmk_r1(sm->pmk_r0, sm->pmk_r0_name, sm->r1kh_id,
542 			  sm->own_addr, sm->pmk_r1, sm->pmk_r1_name);
543 	wpa_hexdump_key(MSG_DEBUG, "FT: PMK-R1", sm->pmk_r1, PMK_LEN);
544 	wpa_hexdump(MSG_DEBUG, "FT: PMKR1Name",
545 		    sm->pmk_r1_name, WPA_PMK_NAME_LEN);
546 
547 	bssid = target_ap;
548 	ptk_len = sm->pairwise_cipher == WPA_CIPHER_CCMP ? 48 : 64;
549 	wpa_pmk_r1_to_ptk(sm->pmk_r1, sm->snonce, ftie->anonce, sm->own_addr,
550 			  bssid, sm->pmk_r1_name,
551 			  (u8 *) &sm->ptk, ptk_len, ptk_name);
552 	wpa_hexdump_key(MSG_DEBUG, "FT: PTK",
553 			(u8 *) &sm->ptk, ptk_len);
554 	wpa_hexdump(MSG_DEBUG, "FT: PTKName", ptk_name, WPA_PMK_NAME_LEN);
555 
556 	ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, ftie->anonce,
557 				    sm->pmk_r1_name, sm->ptk.kck, bssid);
558 	if (ft_ies) {
559 		wpa_sm_update_ft_ies(sm, sm->mobility_domain,
560 				     ft_ies, ft_ies_len);
561 		os_free(ft_ies);
562 	}
563 
564 	ret = wpa_ft_install_ptk(sm, bssid);
565 
566 	if (ret == 0) {
567 		sm->ft_completed = 1;
568 		if (ft_action) {
569 			/* TODO: trigger re-association to the Target AP;
570 			 * MLME is now doing this automatically, but it should
571 			 * really be done only if we get here successfully. */
572 			os_memcpy(sm->bssid, target_ap, ETH_ALEN);
573 		}
574 	}
575 
576 	return ret;
577 }
578 
579 
wpa_ft_is_completed(struct wpa_sm * sm)580 int wpa_ft_is_completed(struct wpa_sm *sm)
581 {
582 	if (sm == NULL)
583 		return 0;
584 
585 	if (sm->key_mgmt != WPA_KEY_MGMT_FT_IEEE8021X &&
586 	    sm->key_mgmt != WPA_KEY_MGMT_FT_PSK)
587 		return 0;
588 
589 	return sm->ft_completed;
590 }
591 
592 
wpa_ft_process_gtk_subelem(struct wpa_sm * sm,const u8 * gtk_elem,size_t gtk_elem_len)593 static int wpa_ft_process_gtk_subelem(struct wpa_sm *sm, const u8 *gtk_elem,
594 				      size_t gtk_elem_len)
595 {
596 	u8 gtk[32];
597 	int keyidx;
598 	wpa_alg alg;
599 	size_t gtk_len, keylen, rsc_len;
600 
601 	if (gtk_elem == NULL) {
602 		wpa_printf(MSG_DEBUG, "FT: No GTK included in FTIE");
603 		return 0;
604 	}
605 
606 	wpa_hexdump_key(MSG_DEBUG, "FT: Received GTK in Reassoc Resp",
607 			gtk_elem, gtk_elem_len);
608 
609 	if (gtk_elem_len < 10 + 24 || (gtk_elem_len - 10) % 8 ||
610 	    gtk_elem_len - 18 > sizeof(gtk)) {
611 		wpa_printf(MSG_DEBUG, "FT: Invalid GTK sub-elem "
612 			   "length %lu", (unsigned long) gtk_elem_len);
613 		return -1;
614 	}
615 	gtk_len = gtk_elem_len - 18;
616 	if (aes_unwrap(sm->ptk.kek, gtk_len / 8, gtk_elem + 10, gtk)) {
617 		wpa_printf(MSG_WARNING, "FT: AES unwrap failed - could not "
618 			   "decrypt GTK");
619 		return -1;
620 	}
621 
622 	switch (sm->group_cipher) {
623 	case WPA_CIPHER_CCMP:
624 		keylen = 16;
625 		rsc_len = 6;
626 		alg = WPA_ALG_CCMP;
627 		break;
628 	case WPA_CIPHER_TKIP:
629 		keylen = 32;
630 		rsc_len = 6;
631 		alg = WPA_ALG_TKIP;
632 		break;
633 	case WPA_CIPHER_WEP104:
634 		keylen = 13;
635 		rsc_len = 0;
636 		alg = WPA_ALG_WEP;
637 		break;
638 	case WPA_CIPHER_WEP40:
639 		keylen = 5;
640 		rsc_len = 0;
641 		alg = WPA_ALG_WEP;
642 		break;
643 	default:
644 		wpa_printf(MSG_WARNING, "WPA: Unsupported Group Cipher %d",
645 			   sm->group_cipher);
646 		return -1;
647 	}
648 
649 	if (gtk_len < keylen) {
650 		wpa_printf(MSG_DEBUG, "FT: Too short GTK in FTIE");
651 		return -1;
652 	}
653 
654 	/* Key Info[1] | Key Length[1] | RSC[8] | Key[5..32]. */
655 
656 	keyidx = gtk_elem[0] & 0x03;
657 
658 	if (gtk_elem[1] != keylen) {
659 		wpa_printf(MSG_DEBUG, "FT: GTK length mismatch: received %d "
660 			   "negotiated %lu",
661 			   gtk_elem[1], (unsigned long) keylen);
662 		return -1;
663 	}
664 
665 	wpa_hexdump_key(MSG_DEBUG, "FT: GTK from Reassoc Resp", gtk, keylen);
666 	if (wpa_sm_set_key(sm, alg, (u8 *) "\xff\xff\xff\xff\xff\xff",
667 			   keyidx, 0, gtk_elem + 2, rsc_len, gtk, keylen) <
668 	    0) {
669 		wpa_printf(MSG_WARNING, "WPA: Failed to set GTK to the "
670 			   "driver.");
671 		return -1;
672 	}
673 
674 	return 0;
675 }
676 
677 
678 #ifdef CONFIG_IEEE80211W
wpa_ft_process_igtk_subelem(struct wpa_sm * sm,const u8 * igtk_elem,size_t igtk_elem_len)679 static int wpa_ft_process_igtk_subelem(struct wpa_sm *sm, const u8 *igtk_elem,
680 				       size_t igtk_elem_len)
681 {
682 	u8 igtk[WPA_IGTK_LEN];
683 	u16 keyidx;
684 
685 	if (sm->mgmt_group_cipher != WPA_CIPHER_AES_128_CMAC)
686 		return 0;
687 
688 	if (igtk_elem == NULL) {
689 		wpa_printf(MSG_DEBUG, "FT: No IGTK included in FTIE");
690 		return 0;
691 	}
692 
693 	wpa_hexdump_key(MSG_DEBUG, "FT: Received IGTK in Reassoc Resp",
694 			igtk_elem, igtk_elem_len);
695 
696 	if (igtk_elem_len != 2 + 6 + 1 + WPA_IGTK_LEN + 8) {
697 		wpa_printf(MSG_DEBUG, "FT: Invalid IGTK sub-elem "
698 			   "length %lu", (unsigned long) igtk_elem_len);
699 		return -1;
700 	}
701 	if (igtk_elem[8] != WPA_IGTK_LEN) {
702 		wpa_printf(MSG_DEBUG, "FT: Invalid IGTK sub-elem Key Length "
703 			   "%d", igtk_elem[8]);
704 		return -1;
705 	}
706 
707 	if (aes_unwrap(sm->ptk.kek, WPA_IGTK_LEN / 8, igtk_elem + 9, igtk)) {
708 		wpa_printf(MSG_WARNING, "FT: AES unwrap failed - could not "
709 			   "decrypt IGTK");
710 		return -1;
711 	}
712 
713 	/* KeyID[2] | IPN[6] | Key Length[1] | Key[16+8] */
714 
715 	keyidx = WPA_GET_LE16(igtk_elem);
716 
717 	wpa_hexdump_key(MSG_DEBUG, "FT: IGTK from Reassoc Resp", igtk,
718 			WPA_IGTK_LEN);
719 	if (wpa_sm_set_key(sm, WPA_ALG_IGTK, (u8 *) "\xff\xff\xff\xff\xff\xff",
720 			   keyidx, 0, igtk_elem + 2, 6, igtk, WPA_IGTK_LEN) <
721 	    0) {
722 		wpa_printf(MSG_WARNING, "WPA: Failed to set IGTK to the "
723 			   "driver.");
724 		return -1;
725 	}
726 
727 	return 0;
728 }
729 #endif /* CONFIG_IEEE80211W */
730 
731 
wpa_ft_validate_reassoc_resp(struct wpa_sm * sm,const u8 * ies,size_t ies_len,const u8 * src_addr)732 int wpa_ft_validate_reassoc_resp(struct wpa_sm *sm, const u8 *ies,
733 				 size_t ies_len, const u8 *src_addr)
734 {
735 	struct wpa_ft_ies parse;
736 	struct rsn_mdie *mdie;
737 	struct rsn_ftie *ftie;
738 	size_t count;
739 	u8 mic[16];
740 
741 	wpa_hexdump(MSG_DEBUG, "FT: Response IEs", ies, ies_len);
742 
743 	if (sm->key_mgmt != WPA_KEY_MGMT_FT_IEEE8021X &&
744 	    sm->key_mgmt != WPA_KEY_MGMT_FT_PSK) {
745 		wpa_printf(MSG_DEBUG, "FT: Reject FT IEs since FT is not "
746 			   "enabled for this connection");
747 		return -1;
748 	}
749 
750 	if (wpa_ft_parse_ies(ies, ies_len, &parse) < 0) {
751 		wpa_printf(MSG_DEBUG, "FT: Failed to parse IEs");
752 		return -1;
753 	}
754 
755 	mdie = (struct rsn_mdie *) parse.mdie;
756 	if (mdie == NULL || parse.mdie_len < sizeof(*mdie) ||
757 	    os_memcmp(mdie->mobility_domain, sm->mobility_domain,
758 		      MOBILITY_DOMAIN_ID_LEN) != 0) {
759 		wpa_printf(MSG_DEBUG, "FT: Invalid MDIE");
760 		return -1;
761 	}
762 
763 	ftie = (struct rsn_ftie *) parse.ftie;
764 	if (ftie == NULL || parse.ftie_len < sizeof(*ftie)) {
765 		wpa_printf(MSG_DEBUG, "FT: Invalid FTIE");
766 		return -1;
767 	}
768 
769 	if (parse.r0kh_id == NULL) {
770 		wpa_printf(MSG_DEBUG, "FT: No R0KH-ID subelem in FTIE");
771 		return -1;
772 	}
773 
774 	if (parse.r0kh_id_len != sm->r0kh_id_len ||
775 	    os_memcmp(parse.r0kh_id, sm->r0kh_id, parse.r0kh_id_len) != 0) {
776 		wpa_printf(MSG_DEBUG, "FT: R0KH-ID in FTIE did not match with "
777 			   "the current R0KH-ID");
778 		wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID in FTIE",
779 			    parse.r0kh_id, parse.r0kh_id_len);
780 		wpa_hexdump(MSG_DEBUG, "FT: The current R0KH-ID",
781 			    sm->r0kh_id, sm->r0kh_id_len);
782 		return -1;
783 	}
784 
785 	if (parse.r1kh_id == NULL) {
786 		wpa_printf(MSG_DEBUG, "FT: No R1KH-ID subelem in FTIE");
787 		return -1;
788 	}
789 
790 	if (os_memcmp(parse.r1kh_id, sm->r1kh_id, FT_R1KH_ID_LEN) != 0) {
791 		wpa_printf(MSG_DEBUG, "FT: Unknown R1KH-ID used in "
792 			   "ReassocResp");
793 		return -1;
794 	}
795 
796 	if (parse.rsn_pmkid == NULL ||
797 	    os_memcmp(parse.rsn_pmkid, sm->pmk_r1_name, WPA_PMK_NAME_LEN)) {
798 		wpa_printf(MSG_DEBUG, "FT: No matching PMKR1Name (PMKID) in "
799 			   "RSNIE (pmkid=%d)", !!parse.rsn_pmkid);
800 		return -1;
801 	}
802 
803 	count = 3;
804 	if (parse.tie)
805 		count++;
806 
807 	if (ftie->mic_control[1] != count) {
808 		wpa_printf(MSG_DEBUG, "FT: Unexpected IE count in FTIE (%d)",
809 			   ftie->mic_control[1]);
810 		return -1;
811 	}
812 
813 	if (wpa_ft_mic(sm->ptk.kck, sm->own_addr, src_addr, 6,
814 		       parse.mdie - 2, parse.mdie_len + 2,
815 		       parse.ftie - 2, parse.ftie_len + 2,
816 		       parse.rsn - 2, parse.rsn_len + 2, NULL, 0,
817 		       mic) < 0) {
818 		wpa_printf(MSG_DEBUG, "FT: Failed to calculate MIC");
819 		return -1;
820 	}
821 
822 	if (os_memcmp(mic, ftie->mic, 16) != 0) {
823 		wpa_printf(MSG_DEBUG, "FT: Invalid MIC in FTIE");
824 		wpa_hexdump(MSG_MSGDUMP, "FT: Received MIC", ftie->mic, 16);
825 		wpa_hexdump(MSG_MSGDUMP, "FT: Calculated MIC", mic, 16);
826 		return -1;
827 	}
828 
829 	if (wpa_ft_process_gtk_subelem(sm, parse.gtk, parse.gtk_len) < 0)
830 		return -1;
831 
832 #ifdef CONFIG_IEEE80211W
833 	if (wpa_ft_process_igtk_subelem(sm, parse.igtk, parse.igtk_len) < 0)
834 		return -1;
835 #endif /* CONFIG_IEEE80211W */
836 
837 	return 0;
838 }
839 
840 
841 /**
842  * wpa_ft_start_over_ds - Generate over-the-DS auth request
843  * @sm: Pointer to WPA state machine data from wpa_sm_init()
844  * Returns: 0 on success, -1 on failure
845  */
wpa_ft_start_over_ds(struct wpa_sm * sm,const u8 * target_ap)846 int wpa_ft_start_over_ds(struct wpa_sm *sm, const u8 *target_ap)
847 {
848 	u8 *ft_ies;
849 	size_t ft_ies_len;
850 
851 	wpa_printf(MSG_DEBUG, "FT: Request over-the-DS with " MACSTR,
852 		   MAC2STR(target_ap));
853 
854 	/* Generate a new SNonce */
855 	if (os_get_random(sm->snonce, WPA_NONCE_LEN)) {
856 		wpa_printf(MSG_INFO, "FT: Failed to generate a new SNonce");
857 		return -1;
858 	}
859 
860 	ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, NULL, sm->pmk_r0_name,
861 				    NULL, target_ap);
862 	if (ft_ies) {
863 		sm->over_the_ds_in_progress = 1;
864 		os_memcpy(sm->target_ap, target_ap, ETH_ALEN);
865 		wpa_sm_send_ft_action(sm, 1, target_ap, ft_ies, ft_ies_len);
866 		os_free(ft_ies);
867 	}
868 
869 	return 0;
870 }
871 
872 #endif /* CONFIG_IEEE80211R */
873