1 /*
2  * WPA Supplicant - IEEE 802.11r - Fast BSS Transition
3  * Copyright (c) 2006-2018, 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 #define DEFAULT_KEK_LEN 16
22 
wpa_derive_ptk_ft(struct wpa_sm * sm,const unsigned char * src_addr,const struct wpa_eapol_key * key,struct wpa_ptk * ptk)23 int wpa_derive_ptk_ft(struct wpa_sm *sm, const unsigned char *src_addr,
24 		      const struct wpa_eapol_key *key, struct wpa_ptk *ptk)
25 {
26 	u8 ptk_name[WPA_PMK_NAME_LEN];
27 	const u8 *anonce = key->key_nonce;
28 
29 	if (sm->xxkey_len == 0) {
30 		wpa_printf(MSG_DEBUG, "FT: XXKey not available for key "
31 			   "derivation");
32 		return -1;
33 	}
34 
35 	wpa_hexdump_key(MSG_DEBUG, "FT: xxkey", sm->xxkey, sm->xxkey_len);
36 	wpa_hexdump_key(MSG_DEBUG, "FT: ssid", sm->ssid, sm->ssid_len);
37 	wpa_hexdump_key(MSG_DEBUG, "FT: r0kh_id", sm->r0kh_id, sm->r0kh_id_len);
38 	wpa_derive_pmk_r0(sm->xxkey, sm->xxkey_len, sm->ssid,
39 			  sm->ssid_len, sm->mobility_domain,
40 			  sm->r0kh_id, sm->r0kh_id_len, sm->own_addr,
41 			  sm->pmk_r0, sm->pmk_r0_name);
42 	wpa_hexdump_key(MSG_DEBUG, "FT: PMK-R0", sm->pmk_r0, PMK_LEN);
43 	wpa_hexdump(MSG_DEBUG, "FT: PMKR0Name",
44 		    sm->pmk_r0_name, WPA_PMK_NAME_LEN);
45 	wpa_derive_pmk_r1(sm->pmk_r0, sm->pmk_r0_name, sm->r1kh_id,
46 			  sm->own_addr, sm->pmk_r1, sm->pmk_r1_name);
47 	wpa_hexdump_key(MSG_DEBUG, "FT: PMK-R1", sm->pmk_r1, PMK_LEN);
48 	wpa_hexdump(MSG_DEBUG, "FT: PMKR1Name", sm->pmk_r1_name,
49 		    WPA_PMK_NAME_LEN);
50 	return wpa_pmk_r1_to_ptk(sm->pmk_r1, sm->snonce, anonce, sm->own_addr,
51 				 sm->bssid, sm->pmk_r1_name, ptk, ptk_name,
52 				 sm->key_mgmt, sm->pairwise_cipher);
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  */
wpa_sm_set_ft_params(struct wpa_sm * sm,const u8 * ies,size_t ies_len)63 int 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 (!get_ie(ies, ies_len, WLAN_EID_MOBILITY_DOMAIN)) {
71 		os_free(sm->assoc_resp_ies);
72 		sm->assoc_resp_ies = NULL;
73 		sm->assoc_resp_ies_len = 0;
74 		os_memset(sm->mobility_domain, 0, MOBILITY_DOMAIN_ID_LEN);
75 		os_memset(sm->r0kh_id, 0, FT_R0KH_ID_MAX_LEN);
76 		sm->r0kh_id_len = 0;
77 		os_memset(sm->r1kh_id, 0, FT_R1KH_ID_LEN);
78 		sm->ft_protocol = 0;
79 		return 0;
80 	}
81 
82 	if (wpa_ft_parse_ies(ies, ies_len, &ft) < 0)
83 		return -1;
84 
85 	if (ft.mdie_len < MOBILITY_DOMAIN_ID_LEN + 1)
86 		return -1;
87 
88 	wpa_hexdump(MSG_DEBUG, "FT: Mobility domain",
89 		    ft.mdie, MOBILITY_DOMAIN_ID_LEN);
90 	os_memcpy(sm->mobility_domain, ft.mdie, MOBILITY_DOMAIN_ID_LEN);
91 	sm->mdie_ft_capab = ft.mdie[MOBILITY_DOMAIN_ID_LEN];
92 	wpa_printf(MSG_DEBUG, "FT: Capability and Policy: 0x%02x",
93 		   sm->mdie_ft_capab);
94 
95 	if (ft.r0kh_id) {
96 		wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID",
97 			    ft.r0kh_id, ft.r0kh_id_len);
98 		os_memcpy(sm->r0kh_id, ft.r0kh_id, ft.r0kh_id_len);
99 		sm->r0kh_id_len = ft.r0kh_id_len;
100 	} else {
101 		/* FIX: When should R0KH-ID be cleared? We need to keep the
102 		 * old R0KH-ID in order to be able to use this during FT. */
103 		/*
104 		 * os_memset(sm->r0kh_id, 0, FT_R0KH_ID_LEN);
105 		 * sm->r0kh_id_len = 0;
106 		 */
107 	}
108 
109 	if (ft.r1kh_id) {
110 		wpa_hexdump(MSG_DEBUG, "FT: R1KH-ID",
111 			    ft.r1kh_id, FT_R1KH_ID_LEN);
112 		os_memcpy(sm->r1kh_id, ft.r1kh_id, FT_R1KH_ID_LEN);
113 	} else
114 		os_memset(sm->r1kh_id, 0, FT_R1KH_ID_LEN);
115 
116 	os_free(sm->assoc_resp_ies);
117 	sm->assoc_resp_ies = os_malloc(ft.mdie_len + 2 + ft.ftie_len + 2);
118 	if (sm->assoc_resp_ies) {
119 		u8 *pos = sm->assoc_resp_ies;
120 
121 		os_memcpy(pos, ft.mdie - 2, ft.mdie_len + 2);
122 		pos += ft.mdie_len + 2;
123 
124 		if (ft.ftie) {
125 			os_memcpy(pos, ft.ftie - 2, ft.ftie_len + 2);
126 			pos += ft.ftie_len + 2;
127 		}
128 		sm->assoc_resp_ies_len = pos - sm->assoc_resp_ies;
129 		wpa_hexdump(MSG_DEBUG, "FT: Stored MDIE and FTIE from "
130 			    "(Re)Association Response",
131 			    sm->assoc_resp_ies, sm->assoc_resp_ies_len);
132 	}
133 
134 	return 0;
135 }
136 
137 /**
138  * wpa_ft_gen_req_ies - Generate FT (IEEE 802.11r) IEs for Auth/ReAssoc Request
139  * @sm: Pointer to WPA state machine data from wpa_sm_init()
140  * @len: Buffer for returning the length of the IEs
141  * @anonce: ANonce or %NULL if not yet available
142  * @pmk_name: PMKR0Name or PMKR1Name to be added into the RSN IE PMKID List
143  * @kck: 128-bit KCK for MIC or %NULL if no MIC is used
144  * @kck_len: KCK length in octet
145  * @target_ap: Target AP address
146  * @ric_ies: Optional IE(s), e.g., WMM TSPEC(s), for RIC-Request or %NULL
147  * @ric_ies_len: Length of ric_ies buffer in octets
148  * @ap_mdie: Mobility Domain IE from the target AP
149  * Returns: Pointer to buffer with IEs or %NULL on failure
150  *
151  * Caller is responsible for freeing the returned buffer with os_free();
152  */
wpa_ft_gen_req_ies(struct wpa_sm * sm,size_t * len,const u8 * anonce,const u8 * pmk_name,const u8 * kck,size_t kck_len,const u8 * target_ap,const u8 * ric_ies,size_t ric_ies_len,const u8 * ap_mdie)153 static u8 * wpa_ft_gen_req_ies(struct wpa_sm *sm, size_t *len,
154 			       const u8 *anonce, const u8 *pmk_name,
155 			       const u8 *kck, size_t kck_len,
156 			       const u8 *target_ap,
157 			       const u8 *ric_ies, size_t ric_ies_len,
158 			       const u8 *ap_mdie)
159 {
160 	size_t buf_len;
161 	u8 *buf, *pos, *ftie_len, *ftie_pos;
162 	struct rsn_mdie *mdie;
163 	struct rsn_ftie *ftie;
164 	struct rsn_ie_hdr *rsnie;
165 	int mdie_len;
166 	u16 capab;
167 
168 	sm->ft_completed = 0;
169 
170 	buf_len = 2 + sizeof(struct rsn_mdie) + 2 + sizeof(struct rsn_ftie) +
171 		2 + sm->r0kh_id_len + ric_ies_len + 100;
172 	buf = os_zalloc(buf_len);
173 	if (buf == NULL)
174 		return NULL;
175 	pos = buf;
176 
177 	/* RSNIE[PMKR0Name/PMKR1Name] */
178 	rsnie = (struct rsn_ie_hdr *) pos;
179 	rsnie->elem_id = WLAN_EID_RSN;
180 	WPA_PUT_LE16(rsnie->version, RSN_VERSION);
181 	pos = (u8 *) (rsnie + 1);
182 
183 	/* Group Suite Selector */
184 	if (sm->group_cipher != WPA_CIPHER_CCMP &&
185 	    sm->group_cipher != WPA_CIPHER_GCMP &&
186 	    sm->group_cipher != WPA_CIPHER_TKIP) {
187 		wpa_printf(MSG_WARNING, "FT: Invalid group cipher (%d)",
188 			   sm->group_cipher);
189 		os_free(buf);
190 		return NULL;
191 	}
192 	RSN_SELECTOR_PUT(pos, wpa_cipher_to_suite(WPA_PROTO_RSN,
193 						  sm->group_cipher));
194 	pos += RSN_SELECTOR_LEN;
195 
196 	/* Pairwise Suite Count */
197 	WPA_PUT_LE16(pos, 1);
198 	pos += 2;
199 
200 	/* Pairwise Suite List */
201 	if (!wpa_cipher_valid_pairwise(sm->pairwise_cipher)) {
202 		wpa_printf(MSG_WARNING, "FT: Invalid pairwise cipher (%d)",
203 			   sm->pairwise_cipher);
204 		os_free(buf);
205 		return NULL;
206 	}
207 	RSN_SELECTOR_PUT(pos, wpa_cipher_to_suite(WPA_PROTO_RSN,
208 						  sm->pairwise_cipher));
209 	pos += RSN_SELECTOR_LEN;
210 
211 	/* Authenticated Key Management Suite Count */
212 	WPA_PUT_LE16(pos, 1);
213 	pos += 2;
214 
215 	/* Authenticated Key Management Suite List */
216 	if (sm->key_mgmt == WPA_KEY_MGMT_FT_IEEE8021X)
217 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_802_1X);
218 	else if (sm->key_mgmt == WPA_KEY_MGMT_FT_PSK)
219 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_PSK);
220 	else if (sm->key_mgmt == WPA_KEY_MGMT_FT_SAE)
221 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_SAE);
222 	else {
223 		wpa_printf(MSG_WARNING, "FT: Invalid key management type (%d)",
224 			   sm->key_mgmt);
225 		os_free(buf);
226 		return NULL;
227 	}
228 	pos += RSN_SELECTOR_LEN;
229 
230 	/* RSN Capabilities */
231 	capab = 0;
232 #ifdef CONFIG_IEEE80211W
233 	if (sm->mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC)
234 		capab |= WPA_CAPABILITY_MFPC;
235 #endif /* CONFIG_IEEE80211W */
236 	WPA_PUT_LE16(pos, capab);
237 	pos += 2;
238 
239 	/* PMKID Count */
240 	WPA_PUT_LE16(pos, 1);
241 	pos += 2;
242 
243 	/* PMKID List [PMKR0Name/PMKR1Name] */
244 	os_memcpy(pos, pmk_name, WPA_PMK_NAME_LEN);
245 	pos += WPA_PMK_NAME_LEN;
246 
247 #ifdef CONFIG_IEEE80211W
248 	if (sm->mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC) {
249 		/* Management Group Cipher Suite */
250 		RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_AES_128_CMAC);
251 		pos += RSN_SELECTOR_LEN;
252 	}
253 #endif /* CONFIG_IEEE80211W */
254 
255 	rsnie->len = (pos - (u8 *) rsnie) - 2;
256 
257 	/* MDIE */
258 	mdie_len = wpa_ft_add_mdie(sm, pos, buf_len - (pos - buf), ap_mdie);
259 	if (mdie_len <= 0) {
260 		os_free(buf);
261 		return NULL;
262 	}
263 	mdie = (struct rsn_mdie *) (pos + 2);
264 	pos += mdie_len;
265 
266 	/* FTIE[SNonce, [R1KH-ID,] R0KH-ID ] */
267 	ftie_pos = pos;
268 	*pos++ = WLAN_EID_FAST_BSS_TRANSITION;
269 	ftie_len = pos++;
270 	ftie = (struct rsn_ftie *) pos;
271 	pos += sizeof(*ftie);
272 	os_memcpy(ftie->snonce, sm->snonce, WPA_NONCE_LEN);
273 	if (anonce)
274 		os_memcpy(ftie->anonce, anonce, WPA_NONCE_LEN);
275 	if (kck) {
276 		/* R1KH-ID sub-element in third FT message */
277 		*pos++ = FTIE_SUBELEM_R1KH_ID;
278 		*pos++ = FT_R1KH_ID_LEN;
279 		os_memcpy(pos, sm->r1kh_id, FT_R1KH_ID_LEN);
280 		pos += FT_R1KH_ID_LEN;
281 	}
282 	/* R0KH-ID sub-element */
283 	*pos++ = FTIE_SUBELEM_R0KH_ID;
284 	*pos++ = sm->r0kh_id_len;
285 	os_memcpy(pos, sm->r0kh_id, sm->r0kh_id_len);
286 	pos += sm->r0kh_id_len;
287 	*ftie_len = pos - ftie_len - 1;
288 
289 	if (ric_ies) {
290 		/* RIC Request */
291 		os_memcpy(pos, ric_ies, ric_ies_len);
292 		pos += ric_ies_len;
293 	}
294 
295 	if (kck) {
296 		/*
297 		 * IEEE Std 802.11r-2008, 11A.8.4
298 		 * MIC shall be calculated over:
299 		 * non-AP STA MAC address
300 		 * Target AP MAC address
301 		 * Transaction seq number (5 for ReassocReq, 3 otherwise)
302 		 * RSN IE
303 		 * MDIE
304 		 * FTIE (with MIC field set to 0)
305 		 * RIC-Request (if present)
306 		 */
307 		/* Information element count */
308 		ftie->mic_control[1] = 3 + ieee802_11_ie_count(ric_ies,
309 							       ric_ies_len);
310 		if (wpa_ft_mic(kck, kck_len, sm->own_addr, target_ap, 5,
311 			       ((u8 *) mdie) - 2, 2 + sizeof(*mdie),
312 			       ftie_pos, 2 + *ftie_len,
313 			       (u8 *) rsnie, 2 + rsnie->len, ric_ies,
314 			       ric_ies_len, ftie->mic) < 0) {
315 			wpa_printf(MSG_INFO, "FT: Failed to calculate MIC");
316 			os_free(buf);
317 			return NULL;
318 		}
319 	}
320 
321 	*len = pos - buf;
322 
323 	return buf;
324 }
325 
326 
wpa_ft_install_ptk(struct wpa_sm * sm,const u8 * bssid)327 static int wpa_ft_install_ptk(struct wpa_sm *sm, const u8 *bssid)
328 {
329 	int keylen;
330 	enum wpa_alg alg;
331 	u8 null_rsc[6] = { 0, 0, 0, 0, 0, 0 };
332 
333 	wpa_printf(MSG_DEBUG, "FT: Installing PTK to the driver.");
334 
335 	if (!wpa_cipher_valid_pairwise(sm->pairwise_cipher)) {
336 		wpa_printf(MSG_WARNING, "FT: Unsupported pairwise cipher %d",
337 			   sm->pairwise_cipher);
338 		return -1;
339 	}
340 
341 	alg = wpa_cipher_to_alg(sm->pairwise_cipher);
342 	keylen = wpa_cipher_key_len(sm->pairwise_cipher);
343 
344 	if (wpa_sm_set_key(&(sm->install_ptk), alg, (u8 *)bssid, 0, 1, null_rsc,
345 			   sizeof(null_rsc), (u8 *) sm->ptk.tk, keylen, KEY_FLAG_PAIRWISE) < 0) {
346 		wpa_printf(MSG_WARNING, "FT: Failed to set PTK to the driver");
347 		return -1;
348 	}
349 
350 	return 0;
351 }
352 
353 
354 /**
355  * wpa_ft_prepare_auth_request - Generate over-the-air auth request
356  * @sm: Pointer to WPA state machine data from wpa_sm_init()
357  * @mdie: Target AP MDIE
358  * Returns: 0 on success, -1 on failure
359  */
wpa_ft_prepare_auth_request(struct wpa_sm * sm,const u8 * mdie)360 int wpa_ft_prepare_auth_request(struct wpa_sm *sm, const u8 *mdie)
361 {
362 	u8 *ft_ies;
363 	size_t ft_ies_len;
364 
365 	/* Generate a new SNonce */
366 	if (random_get_bytes(sm->snonce, WPA_NONCE_LEN)) {
367 		wpa_printf(MSG_INFO, "FT: Failed to generate a new SNonce");
368 		return -1;
369 	}
370 
371 	ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, NULL, sm->pmk_r0_name,
372 				    NULL, 0, sm->bssid, NULL, 0, mdie);
373 	if (ft_ies) {
374 		wpa_sm_update_ft_ies(sm, sm->mobility_domain,
375 				     ft_ies, ft_ies_len, true);
376 		os_free(ft_ies);
377 	}
378 
379 	return 0;
380 }
381 
382 
wpa_ft_add_mdie(struct wpa_sm * sm,u8 * buf,size_t buf_len,const u8 * ap_mdie)383 int wpa_ft_add_mdie(struct wpa_sm *sm, u8 *buf, size_t buf_len,
384 		    const u8 *ap_mdie)
385 {
386 	u8 *pos = buf;
387 	struct rsn_mdie *mdie;
388 
389 	if (buf_len < 2 + sizeof(*mdie)) {
390 		wpa_printf(MSG_INFO,
391 			   "FT: Failed to add MDIE: short buffer, length=%zu",
392 			   buf_len);
393 		return 0;
394 	}
395 
396 	*pos++ = WLAN_EID_MOBILITY_DOMAIN;
397 	*pos++ = sizeof(*mdie);
398 	mdie = (struct rsn_mdie *) pos;
399 	os_memcpy(mdie->mobility_domain, sm->mobility_domain,
400 		  MOBILITY_DOMAIN_ID_LEN);
401 	mdie->ft_capab = ap_mdie && ap_mdie[1] >= 3 ? ap_mdie[4] :
402 		sm->mdie_ft_capab;
403 
404 	return 2 + sizeof(*mdie);
405 }
406 
407 
wpa_sm_get_ft_md(struct wpa_sm * sm)408 const u8 * wpa_sm_get_ft_md(struct wpa_sm *sm)
409 {
410 	return sm->mobility_domain;
411 }
412 
413 
wpa_ft_process_response(struct wpa_sm * sm,const u8 * ies,size_t ies_len,int ft_action,const u8 * target_ap,const u8 * ric_ies,size_t ric_ies_len)414 int wpa_ft_process_response(struct wpa_sm *sm, const u8 *ies, size_t ies_len,
415 			    int ft_action, const u8 *target_ap,
416 			    const u8 *ric_ies, size_t ric_ies_len)
417 {
418 	u8 *ft_ies;
419 	size_t ft_ies_len;
420 	struct wpa_ft_ies parse;
421 	struct rsn_mdie *mdie;
422 	struct rsn_ftie *ftie;
423 	u8 ptk_name[WPA_PMK_NAME_LEN];
424 	int ret;
425 	const u8 *bssid;
426 
427 	wpa_hexdump(MSG_DEBUG, "FT: Response IEs", ies, ies_len);
428 	wpa_hexdump(MSG_DEBUG, "FT: RIC IEs", ric_ies, ric_ies_len);
429 
430 	if (ft_action) {
431 		if (!sm->over_the_ds_in_progress) {
432 			wpa_printf(MSG_DEBUG, "FT: No over-the-DS in progress "
433 				   "- drop FT Action Response");
434 			return -1;
435 		}
436 
437 		if (os_memcmp(target_ap, sm->target_ap, ETH_ALEN) != 0) {
438 			wpa_printf(MSG_DEBUG, "FT: No over-the-DS in progress "
439 				   "with this Target AP - drop FT Action "
440 				   "Response");
441 			return -1;
442 		}
443 	}
444 
445 	if (!wpa_key_mgmt_ft(sm->key_mgmt)) {
446 		wpa_printf(MSG_DEBUG, "FT: Reject FT IEs since FT is not "
447 			   "enabled for this connection");
448 		return -1;
449 	}
450 
451 	if (wpa_ft_parse_ies(ies, ies_len, &parse) < 0) {
452 		wpa_printf(MSG_DEBUG, "FT: Failed to parse IEs");
453 		return -1;
454 	}
455 
456 	mdie = (struct rsn_mdie *) parse.mdie;
457 	if (mdie == NULL || parse.mdie_len < sizeof(*mdie) ||
458 	    os_memcmp(mdie->mobility_domain, sm->mobility_domain,
459 		      MOBILITY_DOMAIN_ID_LEN) != 0) {
460 		wpa_printf(MSG_DEBUG, "FT: Invalid MDIE");
461 		return -1;
462 	}
463 
464 	ftie = (struct rsn_ftie *) parse.ftie;
465 	if (ftie == NULL || parse.ftie_len < sizeof(*ftie)) {
466 		wpa_printf(MSG_DEBUG, "FT: Invalid FTIE");
467 		return -1;
468 	}
469 
470 	if (os_memcmp(ftie->snonce, sm->snonce, WPA_NONCE_LEN) != 0) {
471 		wpa_printf(MSG_DEBUG, "FT: SNonce mismatch in FTIE");
472 		wpa_hexdump(MSG_DEBUG, "FT: Received SNonce",
473 			    ftie->snonce, WPA_NONCE_LEN);
474 		wpa_hexdump(MSG_DEBUG, "FT: Expected SNonce",
475 			    sm->snonce, WPA_NONCE_LEN);
476 		return -1;
477 	}
478 
479 	if (parse.r0kh_id == NULL) {
480 		wpa_printf(MSG_DEBUG, "FT: No R0KH-ID subelem in FTIE");
481 		return -1;
482 	}
483 
484 	if (parse.r0kh_id_len != sm->r0kh_id_len ||
485 	    os_memcmp_const(parse.r0kh_id, sm->r0kh_id, parse.r0kh_id_len) != 0)
486 	{
487 		wpa_printf(MSG_DEBUG, "FT: R0KH-ID in FTIE did not match with "
488 			   "the current R0KH-ID");
489 		wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID in FTIE",
490 			    parse.r0kh_id, parse.r0kh_id_len);
491 		wpa_hexdump(MSG_DEBUG, "FT: The current R0KH-ID",
492 			    sm->r0kh_id, sm->r0kh_id_len);
493 		return -1;
494 	}
495 
496 	if (parse.r1kh_id == NULL) {
497 		wpa_printf(MSG_DEBUG, "FT: No R1KH-ID subelem in FTIE");
498 		return -1;
499 	}
500 
501 	if (parse.rsn_pmkid == NULL ||
502 	    os_memcmp_const(parse.rsn_pmkid, sm->pmk_r0_name, WPA_PMK_NAME_LEN))
503 	{
504 		wpa_printf(MSG_DEBUG, "FT: No matching PMKR0Name (PMKID) in "
505 			   "RSNIE");
506 		return -1;
507 	}
508 
509 	os_memcpy(sm->r1kh_id, parse.r1kh_id, FT_R1KH_ID_LEN);
510 	wpa_hexdump(MSG_DEBUG, "FT: R1KH-ID", sm->r1kh_id, FT_R1KH_ID_LEN);
511 	wpa_hexdump(MSG_DEBUG, "FT: SNonce", sm->snonce, WPA_NONCE_LEN);
512 	wpa_hexdump(MSG_DEBUG, "FT: ANonce", ftie->anonce, WPA_NONCE_LEN);
513 	os_memcpy(sm->anonce, ftie->anonce, WPA_NONCE_LEN);
514 	wpa_derive_pmk_r1(sm->pmk_r0, sm->pmk_r0_name, sm->r1kh_id,
515 			  sm->own_addr, sm->pmk_r1, sm->pmk_r1_name);
516 	wpa_hexdump_key(MSG_DEBUG, "FT: PMK-R1", sm->pmk_r1, PMK_LEN);
517 	wpa_hexdump(MSG_DEBUG, "FT: PMKR1Name",
518 		    sm->pmk_r1_name, WPA_PMK_NAME_LEN);
519 
520 	bssid = target_ap;
521 
522 	if (wpa_pmk_r1_to_ptk(sm->pmk_r1, sm->snonce, ftie->anonce,
523 			      sm->own_addr, bssid, sm->pmk_r1_name, &sm->ptk,
524 			      ptk_name, sm->key_mgmt, sm->pairwise_cipher) < 0)
525 		return -1;
526 
527 	ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, ftie->anonce,
528 				    sm->pmk_r1_name,
529 				    sm->ptk.kck, sm->ptk.kck_len, bssid,
530 				    ric_ies, ric_ies_len,
531 				    parse.mdie ? parse.mdie - 2 : NULL);
532 	if (ft_ies) {
533 		wpa_sm_update_ft_ies(sm, sm->mobility_domain,
534 				     ft_ies, ft_ies_len, false);
535 		os_free(ft_ies);
536 	}
537 
538 	wpa_sm_mark_authenticated(sm, bssid);
539 	ret = wpa_ft_install_ptk(sm, bssid);
540 	if (ret) {
541 		/*
542 		 * Some drivers do not support key configuration when we are
543 		 * not associated with the target AP. Work around this by
544 		 * trying again after the following reassociation gets
545 		 * completed.
546 		 */
547 		wpa_printf(MSG_DEBUG, "FT: Failed to set PTK prior to "
548 			   "association - try again after reassociation");
549 		sm->set_ptk_after_assoc = 1;
550 	} else
551 		sm->set_ptk_after_assoc = 0;
552 
553 	sm->ft_completed = 1;
554 	if (ft_action) {
555 		/*
556 		 * The caller is expected trigger re-association with the
557 		 * Target AP.
558 		 */
559 		os_memcpy(sm->bssid, target_ap, ETH_ALEN);
560 	}
561 
562 	return 0;
563 }
564 
565 
wpa_ft_is_completed(struct wpa_sm * sm)566 int wpa_ft_is_completed(struct wpa_sm *sm)
567 {
568 	if (sm == NULL)
569 		return 0;
570 
571 	if (!wpa_key_mgmt_ft(sm->key_mgmt))
572 		return 0;
573 
574 	return sm->ft_completed;
575 }
576 
577 
wpa_reset_ft_completed(struct wpa_sm * sm)578 void wpa_reset_ft_completed(struct wpa_sm *sm)
579 {
580 	if (sm != NULL)
581 		sm->ft_completed = 0;
582 }
583 
584 
wpa_ft_process_gtk_subelem(struct wpa_sm * sm,const u8 * gtk_elem,size_t gtk_elem_len)585 static int wpa_ft_process_gtk_subelem(struct wpa_sm *sm, const u8 *gtk_elem,
586 				      size_t gtk_elem_len)
587 {
588 	u8 gtk[32];
589 	int keyidx;
590 	enum wpa_alg alg;
591 	size_t gtk_len, keylen, rsc_len;
592 
593 	if (gtk_elem == NULL) {
594 		wpa_printf(MSG_DEBUG, "FT: No GTK included in FTIE");
595 		return 0;
596 	}
597 
598 	wpa_hexdump_key(MSG_DEBUG, "FT: Received GTK in Reassoc Resp",
599 			gtk_elem, gtk_elem_len);
600 
601 	if (gtk_elem_len < 11 + 24 || (gtk_elem_len - 11) % 8 ||
602 	    gtk_elem_len - 19 > sizeof(gtk)) {
603 		wpa_printf(MSG_DEBUG, "FT: Invalid GTK sub-elem "
604 			   "length %lu", (unsigned long) gtk_elem_len);
605 		return -1;
606 	}
607 	gtk_len = gtk_elem_len - 19;
608 	if (aes_unwrap(sm->ptk.kek, sm->ptk.kek_len, gtk_len / 8, gtk_elem + 11, gtk)) {
609 		wpa_printf(MSG_WARNING, "FT: AES unwrap failed - could not "
610 			   "decrypt GTK");
611 		return -1;
612 	}
613 
614 	keylen = wpa_cipher_key_len(sm->group_cipher);
615 	rsc_len = wpa_cipher_rsc_len(sm->group_cipher);
616 	alg = wpa_cipher_to_alg(sm->group_cipher);
617 	if (alg == WIFI_WPA_ALG_NONE) {
618 		wpa_printf(MSG_WARNING, "WPA: Unsupported Group Cipher %d",
619 			   sm->group_cipher);
620 		return -1;
621 	}
622 
623 	if (gtk_len < keylen) {
624 		wpa_printf(MSG_DEBUG, "FT: Too short GTK in FTIE");
625 		return -1;
626 	}
627 
628 	/* Key Info[2] | Key Length[1] | RSC[8] | Key[5..32]. */
629 
630 	keyidx = WPA_GET_LE16(gtk_elem) & 0x03;
631 
632 	if (gtk_elem[2] != keylen) {
633 		wpa_printf(MSG_DEBUG, "FT: GTK length mismatch: received %d "
634 			   "negotiated %lu",
635 			   gtk_elem[2], (unsigned long) keylen);
636 		return -1;
637 	}
638 
639 	wpa_hexdump_key(MSG_DEBUG, "FT: GTK from Reassoc Resp", gtk, keylen);
640 	if (sm->group_cipher == WPA_CIPHER_TKIP) {
641 		/* Swap Tx/Rx keys for Michael MIC */
642 		u8 tmp[8];
643 		os_memcpy(tmp, gtk + 16, 8);
644 		os_memcpy(gtk + 16, gtk + 24, 8);
645 		os_memcpy(gtk + 24, tmp, 8);
646 	}
647 	if (wpa_sm_set_key(&(sm->install_gtk), alg, sm->bssid, keyidx, 0,
648 			   (u8 *)(gtk_elem + 3), rsc_len, gtk, keylen, KEY_FLAG_GROUP | KEY_FLAG_RX) < 0) {
649 		wpa_printf(MSG_WARNING, "WPA: Failed to set GTK to the "
650 			   "driver.");
651 		return -1;
652 	}
653 
654 	return 0;
655 }
656 
657 
658 #ifdef CONFIG_IEEE80211W
wpa_ft_process_igtk_subelem(struct wpa_sm * sm,const u8 * igtk_elem,size_t igtk_elem_len)659 static int wpa_ft_process_igtk_subelem(struct wpa_sm *sm, const u8 *igtk_elem,
660 				       size_t igtk_elem_len)
661 {
662 	u8 igtk[WPA_IGTK_LEN];
663 
664 	if (sm->mgmt_group_cipher != WPA_CIPHER_AES_128_CMAC)
665 		return 0;
666 
667 	if (igtk_elem == NULL) {
668 		wpa_printf(MSG_DEBUG, "FT: No IGTK included in FTIE");
669 		return 0;
670 	}
671 
672 	wpa_hexdump_key(MSG_DEBUG, "FT: Received IGTK in Reassoc Resp",
673 			igtk_elem, igtk_elem_len);
674 
675 	if (igtk_elem_len != 2 + 6 + 1 + WPA_IGTK_LEN + 8) {
676 		wpa_printf(MSG_DEBUG, "FT: Invalid IGTK sub-elem "
677 			   "length %lu", (unsigned long) igtk_elem_len);
678 		return -1;
679 	}
680 	if (igtk_elem[8] != WPA_IGTK_LEN) {
681 		wpa_printf(MSG_DEBUG, "FT: Invalid IGTK sub-elem Key Length "
682 			   "%d", igtk_elem[8]);
683 		return -1;
684 	}
685 
686 	if (aes_unwrap(sm->ptk.kek, sm->ptk.kek_len, WPA_IGTK_LEN / 8,
687 		       igtk_elem + 9, igtk)) {
688 		wpa_printf(MSG_WARNING, "FT: AES unwrap failed - could not "
689 			   "decrypt IGTK");
690 		return -1;
691 	}
692 
693 	/* KeyID[2] | IPN[6] | Key Length[1] | Key[16+8] */
694 
695 	wpa_hexdump_key(MSG_DEBUG, "FT: IGTK from Reassoc Resp", igtk,
696 			WPA_IGTK_LEN);
697 #ifdef ESP_SUPPLICANT
698         if (esp_wifi_set_igtk_internal(WIFI_IF_STA, (wifi_wpa_igtk_t *)igtk) < 0) {
699 #else
700 	keyidx = WPA_GET_LE16(igtk_elem);
701 	if (wpa_sm_set_key(&(sm->install_gtk), WIFI_WPA_ALG_IGTK, sm->bssid, keyidx, 0,
702 			   (u8 *)(igtk_elem + 2), 6, igtk, WPA_IGTK_LEN, sm->key_entry_valid) < 0) {
703 #endif
704 		wpa_printf(MSG_WARNING, "WPA: Failed to set IGTK to the "
705 			   "driver.");
706 		return -1;
707 	}
708 
709 	return 0;
710 }
711 #endif /* CONFIG_IEEE80211W */
712 
713 
714 int wpa_ft_validate_reassoc_resp(struct wpa_sm *sm, const u8 *ies,
715 				 size_t ies_len, const u8 *src_addr)
716 {
717 	struct wpa_ft_ies parse;
718 	struct rsn_mdie *mdie;
719 	struct rsn_ftie *ftie;
720 	unsigned int count;
721 	u8 mic[WPA_EAPOL_KEY_MIC_MAX_LEN];
722 
723 	wpa_hexdump(MSG_DEBUG, "FT: Response IEs", ies, ies_len);
724 
725 	if (!wpa_key_mgmt_ft(sm->key_mgmt)) {
726 		wpa_printf(MSG_DEBUG, "FT: Reject FT IEs since FT is not "
727 			   "enabled for this connection");
728 		return -1;
729 	}
730 
731 	if (sm->ft_reassoc_completed) {
732 		wpa_printf(MSG_DEBUG, "FT: Reassociation has already been completed for this FT protocol instance - ignore unexpected retransmission");
733 		return 0;
734 	}
735 
736 	if (wpa_ft_parse_ies(ies, ies_len, &parse) < 0) {
737 		wpa_printf(MSG_DEBUG, "FT: Failed to parse IEs");
738 		return -1;
739 	}
740 
741 	mdie = (struct rsn_mdie *) parse.mdie;
742 	if (mdie == NULL || parse.mdie_len < sizeof(*mdie) ||
743 	    os_memcmp(mdie->mobility_domain, sm->mobility_domain,
744 		      MOBILITY_DOMAIN_ID_LEN) != 0) {
745 		wpa_printf(MSG_DEBUG, "FT: Invalid MDIE");
746 		return -1;
747 	}
748 
749 	ftie = (struct rsn_ftie *) parse.ftie;
750 	if (ftie == NULL || parse.ftie_len < sizeof(*ftie)) {
751 		wpa_printf(MSG_DEBUG, "FT: Invalid FTIE");
752 		return -1;
753 	}
754 
755 	if (os_memcmp(ftie->snonce, sm->snonce, WPA_NONCE_LEN) != 0) {
756 		wpa_printf(MSG_DEBUG, "FT: SNonce mismatch in FTIE");
757 		wpa_hexdump(MSG_DEBUG, "FT: Received SNonce",
758 			    ftie->snonce, WPA_NONCE_LEN);
759 		wpa_hexdump(MSG_DEBUG, "FT: Expected SNonce",
760 			    sm->snonce, WPA_NONCE_LEN);
761 		return -1;
762 	}
763 
764 	if (os_memcmp(ftie->anonce, sm->anonce, WPA_NONCE_LEN) != 0) {
765 		wpa_printf(MSG_DEBUG, "FT: ANonce mismatch in FTIE");
766 		wpa_hexdump(MSG_DEBUG, "FT: Received ANonce",
767 			    ftie->anonce, WPA_NONCE_LEN);
768 		wpa_hexdump(MSG_DEBUG, "FT: Expected ANonce",
769 			    sm->anonce, WPA_NONCE_LEN);
770 		return -1;
771 	}
772 
773 	if (parse.r0kh_id == NULL) {
774 		wpa_printf(MSG_DEBUG, "FT: No R0KH-ID subelem in FTIE");
775 		return -1;
776 	}
777 
778 	if (parse.r0kh_id_len != sm->r0kh_id_len ||
779 	    os_memcmp_const(parse.r0kh_id, sm->r0kh_id, parse.r0kh_id_len) != 0)
780 	{
781 		wpa_printf(MSG_DEBUG, "FT: R0KH-ID in FTIE did not match with "
782 			   "the current R0KH-ID");
783 		wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID in FTIE",
784 			    parse.r0kh_id, parse.r0kh_id_len);
785 		wpa_hexdump(MSG_DEBUG, "FT: The current R0KH-ID",
786 			    sm->r0kh_id, sm->r0kh_id_len);
787 		return -1;
788 	}
789 
790 	if (parse.r1kh_id == NULL) {
791 		wpa_printf(MSG_DEBUG, "FT: No R1KH-ID subelem in FTIE");
792 		return -1;
793 	}
794 
795 	if (os_memcmp_const(parse.r1kh_id, sm->r1kh_id, FT_R1KH_ID_LEN) != 0) {
796 		wpa_printf(MSG_DEBUG, "FT: Unknown R1KH-ID used in "
797 			   "ReassocResp");
798 		return -1;
799 	}
800 
801 	if (parse.rsn_pmkid == NULL ||
802 	    os_memcmp_const(parse.rsn_pmkid, sm->pmk_r1_name, WPA_PMK_NAME_LEN))
803 	{
804 		wpa_printf(MSG_DEBUG, "FT: No matching PMKR1Name (PMKID) in "
805 			   "RSNIE (pmkid=%d)", !!parse.rsn_pmkid);
806 		return -1;
807 	}
808 
809 	count = 3;
810 	if (parse.ric)
811 		count += ieee802_11_ie_count(parse.ric, parse.ric_len);
812 	if (ftie->mic_control[1] != count) {
813 		wpa_printf(MSG_DEBUG, "FT: Unexpected IE count in MIC "
814 			   "Control: received %u expected %u",
815 			   ftie->mic_control[1], count);
816 		return -1;
817 	}
818 
819 	if (wpa_ft_mic(sm->ptk.kck, sm->ptk.kck_len, sm->own_addr, src_addr, 6,
820 		       parse.mdie - 2, parse.mdie_len + 2,
821 		       parse.ftie - 2, parse.ftie_len + 2,
822 		       parse.rsn - 2, parse.rsn_len + 2,
823 		       parse.ric, parse.ric_len,
824 		       mic) < 0) {
825 		wpa_printf(MSG_DEBUG, "FT: Failed to calculate MIC");
826 		return -1;
827 	}
828 
829 	if (os_memcmp_const(mic, ftie->mic, 16) != 0) {
830 		wpa_printf(MSG_DEBUG, "FT: Invalid MIC in FTIE");
831 		wpa_hexdump(MSG_MSGDUMP, "FT: Received MIC", ftie->mic, 16);
832 		wpa_hexdump(MSG_MSGDUMP, "FT: Calculated MIC", mic, 16);
833 		return -1;
834 	}
835 
836 	sm->ft_reassoc_completed = 1;
837 	if (wpa_ft_process_gtk_subelem(sm, parse.gtk, parse.gtk_len) < 0)
838 		return -1;
839 
840 #ifdef CONFIG_IEEE80211W
841 	if (wpa_ft_process_igtk_subelem(sm, parse.igtk, parse.igtk_len) < 0)
842 		return -1;
843 #endif /* CONFIG_IEEE80211W */
844 
845 	if (sm->set_ptk_after_assoc) {
846 		wpa_printf(MSG_DEBUG, "FT: Try to set PTK again now that we "
847 			   "are associated");
848 		if (wpa_ft_install_ptk(sm, src_addr) < 0)
849 			return -1;
850 		sm->set_ptk_after_assoc = 0;
851 	}
852 
853 	if (parse.ric) {
854 		wpa_hexdump(MSG_MSGDUMP, "FT: RIC Response",
855 			    parse.ric, parse.ric_len);
856 		/* TODO: parse response and inform driver about results when
857 		 * using wpa_supplicant SME */
858 	}
859 
860 	wpa_printf(MSG_DEBUG, "FT: Completed successfully");
861 
862 	return 0;
863 }
864 
865 
866 /**
867  * wpa_ft_start_over_ds - Generate over-the-DS auth request
868  * @sm: Pointer to WPA state machine data from wpa_sm_init()
869  * @target_ap: Target AP Address
870  * @mdie: Mobility Domain IE from the target AP
871  * Returns: 0 on success, -1 on failure
872  */
873 int wpa_ft_start_over_ds(struct wpa_sm *sm, const u8 *target_ap,
874 			 const u8 *mdie)
875 {
876 	u8 *ft_ies;
877 	size_t ft_ies_len;
878 
879 	wpa_printf(MSG_DEBUG, "FT: Request over-the-DS with " MACSTR,
880 		   MAC2STR(target_ap));
881 
882 	/* Generate a new SNonce */
883 	if (random_get_bytes(sm->snonce, WPA_NONCE_LEN)) {
884 		wpa_printf(MSG_INFO, "FT: Failed to generate a new SNonce");
885 		return -1;
886 	}
887 
888 	ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, NULL, sm->pmk_r0_name,
889 				    NULL, 0, target_ap, NULL, 0, mdie);
890 	if (ft_ies) {
891 		sm->over_the_ds_in_progress = 1;
892 		os_memcpy(sm->target_ap, target_ap, ETH_ALEN);
893 		wpa_sm_send_ft_action(sm, 1, target_ap, ft_ies, ft_ies_len);
894 		os_free(ft_ies);
895 	}
896 
897 	return 0;
898 }
899 
900 #endif /* CONFIG_IEEE80211R */
901