1 /*
2 * WPA Supplicant - Mesh RSN routines
3 * Copyright (c) 2013-2014, cozybit, Inc. All rights reserved.
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9 #include "utils/includes.h"
10
11 #include "utils/common.h"
12 #include "utils/eloop.h"
13 #include "crypto/sha256.h"
14 #include "crypto/random.h"
15 #include "crypto/aes.h"
16 #include "crypto/aes_siv.h"
17 #include "rsn_supp/wpa.h"
18 #include "ap/hostapd.h"
19 #include "ap/wpa_auth.h"
20 #include "ap/sta_info.h"
21 #include "ap/ieee802_11.h"
22 #include "wpa_supplicant_i.h"
23 #include "driver_i.h"
24 #include "wpas_glue.h"
25 #include "mesh_mpm.h"
26 #include "mesh_rsn.h"
27
28 #define MESH_AUTH_TIMEOUT 10
29 #define MESH_AUTH_RETRY 3
30
mesh_auth_timer(void * eloop_ctx,void * user_data)31 void mesh_auth_timer(void *eloop_ctx, void *user_data)
32 {
33 struct wpa_supplicant *wpa_s = eloop_ctx;
34 struct sta_info *sta = user_data;
35 struct hostapd_data *hapd;
36
37 if (sta->sae->state != SAE_ACCEPTED) {
38 wpa_printf(MSG_DEBUG, "AUTH: Re-authenticate with " MACSTR
39 " (attempt %d) ",
40 MAC2STR(sta->addr), sta->sae_auth_retry);
41 wpa_msg(wpa_s, MSG_INFO, MESH_SAE_AUTH_FAILURE "addr=" MACSTR,
42 MAC2STR(sta->addr));
43 if (sta->sae_auth_retry < MESH_AUTH_RETRY) {
44 mesh_rsn_auth_sae_sta(wpa_s, sta);
45 } else {
46 hapd = wpa_s->ifmsh->bss[0];
47
48 if (sta->sae_auth_retry > MESH_AUTH_RETRY) {
49 ap_free_sta(hapd, sta);
50 return;
51 }
52
53 /* block the STA if exceeded the number of attempts */
54 wpa_mesh_set_plink_state(wpa_s, sta, PLINK_BLOCKED);
55 sta->sae->state = SAE_NOTHING;
56 wpa_msg(wpa_s, MSG_INFO, MESH_SAE_AUTH_BLOCKED "addr="
57 MACSTR " duration=%d",
58 MAC2STR(sta->addr),
59 hapd->conf->ap_max_inactivity);
60 }
61 sta->sae_auth_retry++;
62 }
63 }
64
65
auth_logger(void * ctx,const u8 * addr,logger_level level,const char * txt)66 static void auth_logger(void *ctx, const u8 *addr, logger_level level,
67 const char *txt)
68 {
69 if (addr)
70 wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " - %s",
71 MAC2STR(addr), txt);
72 else
73 wpa_printf(MSG_DEBUG, "AUTH: %s", txt);
74 }
75
76
auth_get_psk(void * ctx,const u8 * addr,const u8 * p2p_dev_addr,const u8 * prev_psk)77 static const u8 *auth_get_psk(void *ctx, const u8 *addr,
78 const u8 *p2p_dev_addr, const u8 *prev_psk)
79 {
80 struct mesh_rsn *mesh_rsn = ctx;
81 struct hostapd_data *hapd = mesh_rsn->wpa_s->ifmsh->bss[0];
82 struct sta_info *sta = ap_get_sta(hapd, addr);
83
84 wpa_printf(MSG_DEBUG, "AUTH: %s (addr=" MACSTR " prev_psk=%p)",
85 __func__, MAC2STR(addr), prev_psk);
86
87 if (sta && sta->auth_alg == WLAN_AUTH_SAE) {
88 if (!sta->sae || prev_psk)
89 return NULL;
90 return sta->sae->pmk;
91 }
92
93 return NULL;
94 }
95
96
auth_set_key(void * ctx,int vlan_id,enum wpa_alg alg,const u8 * addr,int idx,u8 * key,size_t key_len)97 static int auth_set_key(void *ctx, int vlan_id, enum wpa_alg alg,
98 const u8 *addr, int idx, u8 *key, size_t key_len)
99 {
100 struct mesh_rsn *mesh_rsn = ctx;
101 u8 seq[6];
102
103 os_memset(seq, 0, sizeof(seq));
104
105 if (addr) {
106 wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d addr=" MACSTR
107 " key_idx=%d)",
108 __func__, alg, MAC2STR(addr), idx);
109 } else {
110 wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d key_idx=%d)",
111 __func__, alg, idx);
112 }
113 wpa_hexdump_key(MSG_DEBUG, "AUTH: set_key - key", key, key_len);
114
115 return wpa_drv_set_key(mesh_rsn->wpa_s, alg, addr, idx,
116 1, seq, 6, key, key_len);
117 }
118
119
auth_start_ampe(void * ctx,const u8 * addr)120 static int auth_start_ampe(void *ctx, const u8 *addr)
121 {
122 struct mesh_rsn *mesh_rsn = ctx;
123 struct hostapd_data *hapd;
124 struct sta_info *sta;
125
126 if (mesh_rsn->wpa_s->current_ssid->mode != WPAS_MODE_MESH)
127 return -1;
128
129 hapd = mesh_rsn->wpa_s->ifmsh->bss[0];
130 sta = ap_get_sta(hapd, addr);
131 if (sta)
132 eloop_cancel_timeout(mesh_auth_timer, mesh_rsn->wpa_s, sta);
133
134 mesh_mpm_auth_peer(mesh_rsn->wpa_s, addr);
135 return 0;
136 }
137
138
__mesh_rsn_auth_init(struct mesh_rsn * rsn,const u8 * addr)139 static int __mesh_rsn_auth_init(struct mesh_rsn *rsn, const u8 *addr)
140 {
141 struct wpa_auth_config conf;
142 struct wpa_auth_callbacks cb;
143 u8 seq[6] = {};
144
145 wpa_printf(MSG_DEBUG, "AUTH: Initializing group state machine");
146
147 os_memset(&conf, 0, sizeof(conf));
148 conf.wpa = 2;
149 conf.wpa_key_mgmt = WPA_KEY_MGMT_SAE;
150 conf.wpa_pairwise = WPA_CIPHER_CCMP;
151 conf.rsn_pairwise = WPA_CIPHER_CCMP;
152 conf.wpa_group = WPA_CIPHER_CCMP;
153 conf.eapol_version = 0;
154 conf.wpa_group_rekey = -1;
155
156 os_memset(&cb, 0, sizeof(cb));
157 cb.ctx = rsn;
158 cb.logger = auth_logger;
159 cb.get_psk = auth_get_psk;
160 cb.set_key = auth_set_key;
161 cb.start_ampe = auth_start_ampe;
162
163 rsn->auth = wpa_init(addr, &conf, &cb);
164 if (rsn->auth == NULL) {
165 wpa_printf(MSG_DEBUG, "AUTH: wpa_init() failed");
166 return -1;
167 }
168
169 /* TODO: support rekeying */
170 if (random_get_bytes(rsn->mgtk, 16) < 0) {
171 wpa_deinit(rsn->auth);
172 return -1;
173 }
174
175 /* group mgmt */
176 wpa_drv_set_key(rsn->wpa_s, WPA_ALG_IGTK, NULL, 4, 1,
177 seq, sizeof(seq), rsn->mgtk, sizeof(rsn->mgtk));
178
179 /* group privacy / data frames */
180 wpa_drv_set_key(rsn->wpa_s, WPA_ALG_CCMP, NULL, 1, 1,
181 seq, sizeof(seq), rsn->mgtk, sizeof(rsn->mgtk));
182
183 return 0;
184 }
185
186
mesh_rsn_deinit(struct mesh_rsn * rsn)187 static void mesh_rsn_deinit(struct mesh_rsn *rsn)
188 {
189 os_memset(rsn->mgtk, 0, sizeof(rsn->mgtk));
190 if (rsn->auth)
191 wpa_deinit(rsn->auth);
192 }
193
194
mesh_rsn_auth_init(struct wpa_supplicant * wpa_s,struct mesh_conf * conf)195 struct mesh_rsn *mesh_rsn_auth_init(struct wpa_supplicant *wpa_s,
196 struct mesh_conf *conf)
197 {
198 struct mesh_rsn *mesh_rsn;
199 struct hostapd_data *bss = wpa_s->ifmsh->bss[0];
200 const u8 *ie;
201 size_t ie_len;
202
203 mesh_rsn = os_zalloc(sizeof(*mesh_rsn));
204 if (mesh_rsn == NULL)
205 return NULL;
206 mesh_rsn->wpa_s = wpa_s;
207
208 if (__mesh_rsn_auth_init(mesh_rsn, wpa_s->own_addr) < 0) {
209 mesh_rsn_deinit(mesh_rsn);
210 os_free(mesh_rsn);
211 return NULL;
212 }
213
214 bss->wpa_auth = mesh_rsn->auth;
215
216 ie = wpa_auth_get_wpa_ie(mesh_rsn->auth, &ie_len);
217 conf->rsn_ie = (u8 *) ie;
218 conf->rsn_ie_len = ie_len;
219
220 wpa_supplicant_rsn_supp_set_config(wpa_s, wpa_s->current_ssid);
221
222 return mesh_rsn;
223 }
224
225
index_within_array(const int * array,int idx)226 static int index_within_array(const int *array, int idx)
227 {
228 int i;
229
230 for (i = 0; i < idx; i++) {
231 if (array[i] == -1)
232 return 0;
233 }
234
235 return 1;
236 }
237
238
mesh_rsn_sae_group(struct wpa_supplicant * wpa_s,struct sae_data * sae)239 static int mesh_rsn_sae_group(struct wpa_supplicant *wpa_s,
240 struct sae_data *sae)
241 {
242 int *groups = wpa_s->ifmsh->bss[0]->conf->sae_groups;
243
244 /* Configuration may have changed, so validate current index */
245 if (!index_within_array(groups, wpa_s->mesh_rsn->sae_group_index))
246 return -1;
247
248 for (;;) {
249 int group = groups[wpa_s->mesh_rsn->sae_group_index];
250
251 if (group <= 0)
252 break;
253 if (sae_set_group(sae, group) == 0) {
254 wpa_dbg(wpa_s, MSG_DEBUG, "SME: Selected SAE group %d",
255 sae->group);
256 return 0;
257 }
258 wpa_s->mesh_rsn->sae_group_index++;
259 }
260
261 return -1;
262 }
263
264
mesh_rsn_build_sae_commit(struct wpa_supplicant * wpa_s,struct wpa_ssid * ssid,struct sta_info * sta)265 static int mesh_rsn_build_sae_commit(struct wpa_supplicant *wpa_s,
266 struct wpa_ssid *ssid,
267 struct sta_info *sta)
268 {
269 if (ssid->passphrase == NULL) {
270 wpa_msg(wpa_s, MSG_DEBUG, "SAE: No password available");
271 return -1;
272 }
273
274 if (mesh_rsn_sae_group(wpa_s, sta->sae) < 0) {
275 wpa_msg(wpa_s, MSG_DEBUG, "SAE: Failed to select group");
276 return -1;
277 }
278
279 return sae_prepare_commit(wpa_s->own_addr, sta->addr,
280 (u8 *) ssid->passphrase,
281 os_strlen(ssid->passphrase), sta->sae);
282 }
283
284
285 /* initiate new SAE authentication with sta */
mesh_rsn_auth_sae_sta(struct wpa_supplicant * wpa_s,struct sta_info * sta)286 int mesh_rsn_auth_sae_sta(struct wpa_supplicant *wpa_s,
287 struct sta_info *sta)
288 {
289 struct hostapd_data *hapd = wpa_s->ifmsh->bss[0];
290 struct wpa_ssid *ssid = wpa_s->current_ssid;
291 struct rsn_pmksa_cache_entry *pmksa;
292 unsigned int rnd;
293 int ret;
294
295 if (!ssid) {
296 wpa_msg(wpa_s, MSG_DEBUG,
297 "AUTH: No current_ssid known to initiate new SAE");
298 return -1;
299 }
300
301 if (!sta->sae) {
302 sta->sae = os_zalloc(sizeof(*sta->sae));
303 if (sta->sae == NULL)
304 return -1;
305 }
306
307 pmksa = wpa_auth_pmksa_get(hapd->wpa_auth, sta->addr);
308 if (pmksa) {
309 if (!sta->wpa_sm)
310 sta->wpa_sm = wpa_auth_sta_init(hapd->wpa_auth,
311 sta->addr, NULL);
312 if (!sta->wpa_sm) {
313 wpa_printf(MSG_ERROR,
314 "mesh: Failed to initialize RSN state machine");
315 return -1;
316 }
317
318 wpa_printf(MSG_DEBUG,
319 "AUTH: Mesh PMKSA cache entry found for " MACSTR
320 " - try to use PMKSA caching instead of new SAE authentication",
321 MAC2STR(sta->addr));
322 wpa_auth_pmksa_set_to_sm(pmksa, sta->wpa_sm, hapd->wpa_auth,
323 sta->sae->pmkid, sta->sae->pmk);
324 sae_accept_sta(hapd, sta);
325 sta->mesh_sae_pmksa_caching = 1;
326 return 0;
327 }
328 sta->mesh_sae_pmksa_caching = 0;
329
330 if (mesh_rsn_build_sae_commit(wpa_s, ssid, sta))
331 return -1;
332
333 wpa_msg(wpa_s, MSG_DEBUG,
334 "AUTH: started authentication with SAE peer: " MACSTR,
335 MAC2STR(sta->addr));
336
337 wpa_supplicant_set_state(wpa_s, WPA_AUTHENTICATING);
338 ret = auth_sae_init_committed(hapd, sta);
339 if (ret)
340 return ret;
341
342 eloop_cancel_timeout(mesh_auth_timer, wpa_s, sta);
343 rnd = rand() % MESH_AUTH_TIMEOUT;
344 eloop_register_timeout(MESH_AUTH_TIMEOUT + rnd, 0, mesh_auth_timer,
345 wpa_s, sta);
346 return 0;
347 }
348
349
mesh_rsn_get_pmkid(struct mesh_rsn * rsn,struct sta_info * sta,u8 * pmkid)350 void mesh_rsn_get_pmkid(struct mesh_rsn *rsn, struct sta_info *sta, u8 *pmkid)
351 {
352 os_memcpy(pmkid, sta->sae->pmkid, SAE_PMKID_LEN);
353 }
354
355
356 static void
mesh_rsn_derive_aek(struct mesh_rsn * rsn,struct sta_info * sta)357 mesh_rsn_derive_aek(struct mesh_rsn *rsn, struct sta_info *sta)
358 {
359 u8 *myaddr = rsn->wpa_s->own_addr;
360 u8 *peer = sta->addr;
361 u8 *addr1 = peer, *addr2 = myaddr;
362 u8 context[AES_BLOCK_SIZE];
363
364 /* SAE */
365 RSN_SELECTOR_PUT(context, wpa_cipher_to_suite(0, WPA_CIPHER_GCMP));
366
367 if (os_memcmp(myaddr, peer, ETH_ALEN) < 0) {
368 addr1 = myaddr;
369 addr2 = peer;
370 }
371 os_memcpy(context + 4, addr1, ETH_ALEN);
372 os_memcpy(context + 10, addr2, ETH_ALEN);
373
374 sha256_prf(sta->sae->pmk, sizeof(sta->sae->pmk), "AEK Derivation",
375 context, sizeof(context), sta->aek, sizeof(sta->aek));
376 }
377
378
379 /* derive mesh temporal key from pmk */
mesh_rsn_derive_mtk(struct wpa_supplicant * wpa_s,struct sta_info * sta)380 int mesh_rsn_derive_mtk(struct wpa_supplicant *wpa_s, struct sta_info *sta)
381 {
382 u8 *ptr;
383 u8 *min, *max;
384 u16 min_lid, max_lid;
385 size_t nonce_len = sizeof(sta->my_nonce);
386 size_t lid_len = sizeof(sta->my_lid);
387 u8 *myaddr = wpa_s->own_addr;
388 u8 *peer = sta->addr;
389 /* 2 nonces, 2 linkids, akm suite, 2 mac addrs */
390 u8 context[64 + 4 + 4 + 12];
391
392 ptr = context;
393 if (os_memcmp(sta->my_nonce, sta->peer_nonce, nonce_len) < 0) {
394 min = sta->my_nonce;
395 max = sta->peer_nonce;
396 } else {
397 min = sta->peer_nonce;
398 max = sta->my_nonce;
399 }
400 os_memcpy(ptr, min, nonce_len);
401 os_memcpy(ptr + nonce_len, max, nonce_len);
402 ptr += 2 * nonce_len;
403
404 if (sta->my_lid < sta->peer_lid) {
405 min_lid = host_to_le16(sta->my_lid);
406 max_lid = host_to_le16(sta->peer_lid);
407 } else {
408 min_lid = host_to_le16(sta->peer_lid);
409 max_lid = host_to_le16(sta->my_lid);
410 }
411 os_memcpy(ptr, &min_lid, lid_len);
412 os_memcpy(ptr + lid_len, &max_lid, lid_len);
413 ptr += 2 * lid_len;
414
415 /* SAE */
416 RSN_SELECTOR_PUT(ptr, wpa_cipher_to_suite(0, WPA_CIPHER_GCMP));
417 ptr += 4;
418
419 if (os_memcmp(myaddr, peer, ETH_ALEN) < 0) {
420 min = myaddr;
421 max = peer;
422 } else {
423 min = peer;
424 max = myaddr;
425 }
426 os_memcpy(ptr, min, ETH_ALEN);
427 os_memcpy(ptr + ETH_ALEN, max, ETH_ALEN);
428
429 sha256_prf(sta->sae->pmk, sizeof(sta->sae->pmk),
430 "Temporal Key Derivation", context, sizeof(context),
431 sta->mtk, sizeof(sta->mtk));
432 return 0;
433 }
434
435
mesh_rsn_init_ampe_sta(struct wpa_supplicant * wpa_s,struct sta_info * sta)436 void mesh_rsn_init_ampe_sta(struct wpa_supplicant *wpa_s, struct sta_info *sta)
437 {
438 if (random_get_bytes(sta->my_nonce, 32) < 0) {
439 wpa_printf(MSG_INFO, "mesh: Failed to derive random nonce");
440 /* TODO: How to handle this more cleanly? */
441 }
442 os_memset(sta->peer_nonce, 0, 32);
443 mesh_rsn_derive_aek(wpa_s->mesh_rsn, sta);
444 }
445
446
447 /* insert AMPE and encrypted MIC at @ie.
448 * @mesh_rsn: mesh RSN context
449 * @sta: STA we're sending to
450 * @cat: pointer to category code in frame header.
451 * @buf: wpabuf to add encrypted AMPE and MIC to.
452 * */
mesh_rsn_protect_frame(struct mesh_rsn * rsn,struct sta_info * sta,const u8 * cat,struct wpabuf * buf)453 int mesh_rsn_protect_frame(struct mesh_rsn *rsn, struct sta_info *sta,
454 const u8 *cat, struct wpabuf *buf)
455 {
456 struct ieee80211_ampe_ie *ampe;
457 u8 const *ie = wpabuf_head_u8(buf) + wpabuf_len(buf);
458 u8 *ampe_ie = NULL, *mic_ie = NULL, *mic_payload;
459 const u8 *aad[] = { rsn->wpa_s->own_addr, sta->addr, cat };
460 const size_t aad_len[] = { ETH_ALEN, ETH_ALEN, ie - cat };
461 int ret = 0;
462
463 if (AES_BLOCK_SIZE + 2 + sizeof(*ampe) + 2 > wpabuf_tailroom(buf)) {
464 wpa_printf(MSG_ERROR, "protect frame: buffer too small");
465 return -EINVAL;
466 }
467
468 ampe_ie = os_zalloc(2 + sizeof(*ampe));
469 if (!ampe_ie) {
470 wpa_printf(MSG_ERROR, "protect frame: out of memory");
471 return -ENOMEM;
472 }
473
474 mic_ie = os_zalloc(2 + AES_BLOCK_SIZE);
475 if (!mic_ie) {
476 wpa_printf(MSG_ERROR, "protect frame: out of memory");
477 ret = -ENOMEM;
478 goto free;
479 }
480
481 /* IE: AMPE */
482 ampe_ie[0] = WLAN_EID_AMPE;
483 ampe_ie[1] = sizeof(*ampe);
484 ampe = (struct ieee80211_ampe_ie *) (ampe_ie + 2);
485
486 RSN_SELECTOR_PUT(ampe->selected_pairwise_suite,
487 wpa_cipher_to_suite(WPA_PROTO_RSN, WPA_CIPHER_CCMP));
488 os_memcpy(ampe->local_nonce, sta->my_nonce, 32);
489 os_memcpy(ampe->peer_nonce, sta->peer_nonce, 32);
490 /* incomplete: see 13.5.4 */
491 /* TODO: static mgtk for now since we don't support rekeying! */
492 os_memcpy(ampe->mgtk, rsn->mgtk, 16);
493 /* TODO: Populate Key RSC */
494 /* expire in 13 decades or so */
495 os_memset(ampe->key_expiration, 0xff, 4);
496
497 /* IE: MIC */
498 mic_ie[0] = WLAN_EID_MIC;
499 mic_ie[1] = AES_BLOCK_SIZE;
500 wpabuf_put_data(buf, mic_ie, 2);
501 /* MIC field is output ciphertext */
502
503 /* encrypt after MIC */
504 mic_payload = (u8 *) wpabuf_put(buf, 2 + sizeof(*ampe) +
505 AES_BLOCK_SIZE);
506
507 if (aes_siv_encrypt(sta->aek, ampe_ie, 2 + sizeof(*ampe), 3,
508 aad, aad_len, mic_payload)) {
509 wpa_printf(MSG_ERROR, "protect frame: failed to encrypt");
510 ret = -ENOMEM;
511 goto free;
512 }
513
514 free:
515 os_free(ampe_ie);
516 os_free(mic_ie);
517
518 return ret;
519 }
520
521
mesh_rsn_process_ampe(struct wpa_supplicant * wpa_s,struct sta_info * sta,struct ieee802_11_elems * elems,const u8 * cat,const u8 * chosen_pmk,const u8 * start,size_t elems_len)522 int mesh_rsn_process_ampe(struct wpa_supplicant *wpa_s, struct sta_info *sta,
523 struct ieee802_11_elems *elems, const u8 *cat,
524 const u8 *chosen_pmk,
525 const u8 *start, size_t elems_len)
526 {
527 int ret = 0;
528 struct ieee80211_ampe_ie *ampe;
529 u8 null_nonce[32] = {};
530 u8 ampe_eid;
531 u8 ampe_ie_len;
532 u8 *ampe_buf, *crypt = NULL;
533 size_t crypt_len;
534 const u8 *aad[] = { sta->addr, wpa_s->own_addr, cat };
535 const size_t aad_len[] = { ETH_ALEN, ETH_ALEN,
536 (elems->mic - 2) - cat };
537
538 if (!sta->sae) {
539 struct hostapd_data *hapd = wpa_s->ifmsh->bss[0];
540
541 if (!wpa_auth_pmksa_get(hapd->wpa_auth, sta->addr)) {
542 wpa_printf(MSG_INFO,
543 "Mesh RSN: SAE is not prepared yet");
544 return -1;
545 }
546 mesh_rsn_auth_sae_sta(wpa_s, sta);
547 }
548
549 if (chosen_pmk && os_memcmp(chosen_pmk, sta->sae->pmkid, PMKID_LEN)) {
550 wpa_msg(wpa_s, MSG_DEBUG,
551 "Mesh RSN: Invalid PMKID (Chosen PMK did not match calculated PMKID)");
552 return -1;
553 }
554
555 if (!elems->mic || elems->mic_len < AES_BLOCK_SIZE) {
556 wpa_msg(wpa_s, MSG_DEBUG, "Mesh RSN: missing mic ie");
557 return -1;
558 }
559
560 ampe_buf = (u8 *) elems->mic + elems->mic_len;
561 if ((int) elems_len < ampe_buf - start)
562 return -1;
563
564 crypt_len = elems_len - (elems->mic - start);
565 if (crypt_len < 2) {
566 wpa_msg(wpa_s, MSG_DEBUG, "Mesh RSN: missing ampe ie");
567 return -1;
568 }
569
570 /* crypt is modified by siv_decrypt */
571 crypt = os_zalloc(crypt_len);
572 if (!crypt) {
573 wpa_printf(MSG_ERROR, "Mesh RSN: out of memory");
574 ret = -ENOMEM;
575 goto free;
576 }
577
578 os_memcpy(crypt, elems->mic, crypt_len);
579
580 if (aes_siv_decrypt(sta->aek, crypt, crypt_len, 3,
581 aad, aad_len, ampe_buf)) {
582 wpa_printf(MSG_ERROR, "Mesh RSN: frame verification failed!");
583 ret = -1;
584 goto free;
585 }
586
587 ampe_eid = *ampe_buf++;
588 ampe_ie_len = *ampe_buf++;
589
590 if (ampe_eid != WLAN_EID_AMPE ||
591 ampe_ie_len < sizeof(struct ieee80211_ampe_ie)) {
592 wpa_msg(wpa_s, MSG_DEBUG, "Mesh RSN: invalid ampe ie");
593 ret = -1;
594 goto free;
595 }
596
597 ampe = (struct ieee80211_ampe_ie *) ampe_buf;
598 if (os_memcmp(ampe->peer_nonce, null_nonce, 32) != 0 &&
599 os_memcmp(ampe->peer_nonce, sta->my_nonce, 32) != 0) {
600 wpa_msg(wpa_s, MSG_DEBUG, "Mesh RSN: invalid peer nonce");
601 ret = -1;
602 goto free;
603 }
604 os_memcpy(sta->peer_nonce, ampe->local_nonce,
605 sizeof(ampe->local_nonce));
606 os_memcpy(sta->mgtk, ampe->mgtk, sizeof(ampe->mgtk));
607
608 /* todo parse mgtk expiration */
609 free:
610 os_free(crypt);
611 return ret;
612 }
613