1 /*
2  * WPA Supplicant - RSN PMKSA cache
3  * Copyright (c) 2004-2009, 2011-2015, 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 "eloop.h"
13 #include "eapol_supp/eapol_supp_sm.h"
14 #include "wpa.h"
15 #include "wpa_i.h"
16 #include "pmksa_cache.h"
17 
18 #if defined(IEEE8021X_EAPOL) && !defined(CONFIG_NO_WPA)
19 
20 static const int pmksa_cache_max_entries = 32;
21 
22 struct rsn_pmksa_cache {
23 	struct rsn_pmksa_cache_entry *pmksa; /* PMKSA cache */
24 	int pmksa_count; /* number of entries in PMKSA cache */
25 	struct wpa_sm *sm; /* TODO: get rid of this reference(?) */
26 
27 	void (*free_cb)(struct rsn_pmksa_cache_entry *entry, void *ctx,
28 			enum pmksa_free_reason reason);
29 	void *ctx;
30 };
31 
32 
33 static void pmksa_cache_set_expiration(struct rsn_pmksa_cache *pmksa);
34 
35 
36 static void _pmksa_cache_free_entry(struct rsn_pmksa_cache_entry *entry)
37 {
38 	bin_clear_free(entry, sizeof(*entry));
39 }
40 
41 
42 static void pmksa_cache_free_entry(struct rsn_pmksa_cache *pmksa,
43 				   struct rsn_pmksa_cache_entry *entry,
44 				   enum pmksa_free_reason reason)
45 {
46 	wpa_sm_remove_pmkid(pmksa->sm, entry->network_ctx, entry->aa,
47 			    entry->pmkid,
48 			    entry->fils_cache_id_set ? entry->fils_cache_id :
49 			    NULL);
50 	pmksa->pmksa_count--;
51 	pmksa->free_cb(entry, pmksa->ctx, reason);
52 	_pmksa_cache_free_entry(entry);
53 }
54 
55 
56 static void pmksa_cache_expire(void *eloop_ctx, void *timeout_ctx)
57 {
58 	struct rsn_pmksa_cache *pmksa = eloop_ctx;
59 	struct os_reltime now;
60 
61 	os_get_reltime(&now);
62 	while (pmksa->pmksa && pmksa->pmksa->expiration <= now.sec) {
63 		struct rsn_pmksa_cache_entry *entry = pmksa->pmksa;
64 		pmksa->pmksa = entry->next;
65 		wpa_printf(MSG_DEBUG, "RSN: expired PMKSA cache entry for "
66 			   MACSTR, MAC2STR(entry->aa));
67 		pmksa_cache_free_entry(pmksa, entry, PMKSA_EXPIRE);
68 	}
69 
70 	pmksa_cache_set_expiration(pmksa);
71 }
72 
73 
74 static void pmksa_cache_reauth(void *eloop_ctx, void *timeout_ctx)
75 {
76 	struct rsn_pmksa_cache *pmksa = eloop_ctx;
77 	pmksa->sm->cur_pmksa = NULL;
78 	eapol_sm_request_reauth(pmksa->sm->eapol);
79 }
80 
81 
82 static void pmksa_cache_set_expiration(struct rsn_pmksa_cache *pmksa)
83 {
84 	int sec;
85 	struct rsn_pmksa_cache_entry *entry;
86 	struct os_reltime now;
87 
88 	eloop_cancel_timeout(pmksa_cache_expire, pmksa, NULL);
89 	eloop_cancel_timeout(pmksa_cache_reauth, pmksa, NULL);
90 	if (pmksa->pmksa == NULL)
91 		return;
92 	os_get_reltime(&now);
93 	sec = pmksa->pmksa->expiration - now.sec;
94 	if (sec < 0)
95 		sec = 0;
96 	eloop_register_timeout(sec + 1, 0, pmksa_cache_expire, pmksa, NULL);
97 
98 	entry = pmksa->sm->cur_pmksa ? pmksa->sm->cur_pmksa :
99 		pmksa_cache_get(pmksa, pmksa->sm->bssid, NULL, NULL, 0);
100 	if (entry) {
101 		sec = pmksa->pmksa->reauth_time - now.sec;
102 		if (sec < 0)
103 			sec = 0;
104 		eloop_register_timeout(sec, 0, pmksa_cache_reauth, pmksa,
105 				       NULL);
106 	}
107 }
108 
109 
110 /**
111  * pmksa_cache_add - Add a PMKSA cache entry
112  * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
113  * @pmk: The new pairwise master key
114  * @pmk_len: PMK length in bytes, usually PMK_LEN (32)
115  * @pmkid: Calculated PMKID
116  * @kck: Key confirmation key or %NULL if not yet derived
117  * @kck_len: KCK length in bytes
118  * @aa: Authenticator address
119  * @spa: Supplicant address
120  * @network_ctx: Network configuration context for this PMK
121  * @akmp: WPA_KEY_MGMT_* used in key derivation
122  * @cache_id: Pointer to FILS Cache Identifier or %NULL if not advertised
123  * Returns: Pointer to the added PMKSA cache entry or %NULL on error
124  *
125  * This function create a PMKSA entry for a new PMK and adds it to the PMKSA
126  * cache. If an old entry is already in the cache for the same Authenticator,
127  * this entry will be replaced with the new entry. PMKID will be calculated
128  * based on the PMK and the driver interface is notified of the new PMKID.
129  */
130 struct rsn_pmksa_cache_entry *
131 pmksa_cache_add(struct rsn_pmksa_cache *pmksa, const u8 *pmk, size_t pmk_len,
132 		const u8 *pmkid, const u8 *kck, size_t kck_len,
133 		const u8 *aa, const u8 *spa, void *network_ctx, int akmp,
134 		const u8 *cache_id)
135 {
136 	struct rsn_pmksa_cache_entry *entry;
137 	struct os_reltime now;
138 
139 	if (pmk_len > PMK_LEN_MAX)
140 		return NULL;
141 
142 	if (wpa_key_mgmt_suite_b(akmp) && !kck)
143 		return NULL;
144 
145 	entry = os_zalloc(sizeof(*entry));
146 	if (entry == NULL)
147 		return NULL;
148 	os_memcpy(entry->pmk, pmk, pmk_len);
149 	entry->pmk_len = pmk_len;
150 	if (pmkid)
151 		os_memcpy(entry->pmkid, pmkid, PMKID_LEN);
152 	else if (akmp == WPA_KEY_MGMT_IEEE8021X_SUITE_B_192)
153 		rsn_pmkid_suite_b_192(kck, kck_len, aa, spa, entry->pmkid);
154 	else if (wpa_key_mgmt_suite_b(akmp))
155 		rsn_pmkid_suite_b(kck, kck_len, aa, spa, entry->pmkid);
156 	else
157 		rsn_pmkid(pmk, pmk_len, aa, spa, entry->pmkid, akmp);
158 	os_get_reltime(&now);
159 	entry->expiration = now.sec + pmksa->sm->dot11RSNAConfigPMKLifetime;
160 	entry->reauth_time = now.sec + pmksa->sm->dot11RSNAConfigPMKLifetime *
161 		pmksa->sm->dot11RSNAConfigPMKReauthThreshold / 100;
162 	entry->akmp = akmp;
163 	if (cache_id) {
164 		entry->fils_cache_id_set = 1;
165 		os_memcpy(entry->fils_cache_id, cache_id, FILS_CACHE_ID_LEN);
166 	}
167 	os_memcpy(entry->aa, aa, ETH_ALEN);
168 	entry->network_ctx = network_ctx;
169 
170 	return pmksa_cache_add_entry(pmksa, entry);
171 }
172 
173 
174 struct rsn_pmksa_cache_entry *
175 pmksa_cache_add_entry(struct rsn_pmksa_cache *pmksa,
176 		      struct rsn_pmksa_cache_entry *entry)
177 {
178 	struct rsn_pmksa_cache_entry *pos, *prev;
179 
180 	/* Replace an old entry for the same Authenticator (if found) with the
181 	 * new entry */
182 	pos = pmksa->pmksa;
183 	prev = NULL;
184 	while (pos) {
185 		if (os_memcmp(entry->aa, pos->aa, ETH_ALEN) == 0) {
186 			if (pos->pmk_len == entry->pmk_len &&
187 			    os_memcmp_const(pos->pmk, entry->pmk,
188 					    entry->pmk_len) == 0 &&
189 			    os_memcmp_const(pos->pmkid, entry->pmkid,
190 					    PMKID_LEN) == 0) {
191 				wpa_printf(MSG_DEBUG, "WPA: reusing previous "
192 					   "PMKSA entry");
193 				os_free(entry);
194 				return pos;
195 			}
196 			if (prev == NULL)
197 				pmksa->pmksa = pos->next;
198 			else
199 				prev->next = pos->next;
200 
201 			/*
202 			 * If OKC is used, there may be other PMKSA cache
203 			 * entries based on the same PMK. These needs to be
204 			 * flushed so that a new entry can be created based on
205 			 * the new PMK. Only clear other entries if they have a
206 			 * matching PMK and this PMK has been used successfully
207 			 * with the current AP, i.e., if opportunistic flag has
208 			 * been cleared in wpa_supplicant_key_neg_complete().
209 			 */
210 			wpa_printf(MSG_DEBUG, "RSN: Replace PMKSA entry for "
211 				   "the current AP and any PMKSA cache entry "
212 				   "that was based on the old PMK");
213 			if (!pos->opportunistic)
214 				pmksa_cache_flush(pmksa, entry->network_ctx,
215 						  pos->pmk, pos->pmk_len);
216 			pmksa_cache_free_entry(pmksa, pos, PMKSA_REPLACE);
217 			break;
218 		}
219 		prev = pos;
220 		pos = pos->next;
221 	}
222 
223 	if (pmksa->pmksa_count >= pmksa_cache_max_entries && pmksa->pmksa) {
224 		/* Remove the oldest entry to make room for the new entry */
225 		pos = pmksa->pmksa;
226 
227 		if (pos == pmksa->sm->cur_pmksa) {
228 			/*
229 			 * Never remove the current PMKSA cache entry, since
230 			 * it's in use, and removing it triggers a needless
231 			 * deauthentication.
232 			 */
233 			pos = pos->next;
234 			pmksa->pmksa->next = pos ? pos->next : NULL;
235 		} else
236 			pmksa->pmksa = pos->next;
237 
238 		if (pos) {
239 			wpa_printf(MSG_DEBUG, "RSN: removed the oldest idle "
240 				   "PMKSA cache entry (for " MACSTR ") to "
241 				   "make room for new one",
242 				   MAC2STR(pos->aa));
243 			pmksa_cache_free_entry(pmksa, pos, PMKSA_FREE);
244 		}
245 	}
246 
247 	/* Add the new entry; order by expiration time */
248 	pos = pmksa->pmksa;
249 	prev = NULL;
250 	while (pos) {
251 		if (pos->expiration > entry->expiration)
252 			break;
253 		prev = pos;
254 		pos = pos->next;
255 	}
256 	if (prev == NULL) {
257 		entry->next = pmksa->pmksa;
258 		pmksa->pmksa = entry;
259 		pmksa_cache_set_expiration(pmksa);
260 	} else {
261 		entry->next = prev->next;
262 		prev->next = entry;
263 	}
264 	pmksa->pmksa_count++;
265 	wpa_printf(MSG_DEBUG, "RSN: Added PMKSA cache entry for " MACSTR
266 		   " network_ctx=%p akmp=0x%x", MAC2STR(entry->aa),
267 		   entry->network_ctx, entry->akmp);
268 	wpa_sm_add_pmkid(pmksa->sm, entry->network_ctx, entry->aa, entry->pmkid,
269 			 entry->fils_cache_id_set ? entry->fils_cache_id : NULL,
270 			 entry->pmk, entry->pmk_len);
271 
272 	return entry;
273 }
274 
275 
276 /**
277  * pmksa_cache_flush - Flush PMKSA cache entries for a specific network
278  * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
279  * @network_ctx: Network configuration context or %NULL to flush all entries
280  * @pmk: PMK to match for or %NYLL to match all PMKs
281  * @pmk_len: PMK length
282  */
283 void pmksa_cache_flush(struct rsn_pmksa_cache *pmksa, void *network_ctx,
284 		       const u8 *pmk, size_t pmk_len)
285 {
286 	struct rsn_pmksa_cache_entry *entry, *prev = NULL, *tmp;
287 	int removed = 0;
288 
289 	entry = pmksa->pmksa;
290 	while (entry) {
291 		if ((entry->network_ctx == network_ctx ||
292 		     network_ctx == NULL) &&
293 		    (pmk == NULL ||
294 		     (pmk_len == entry->pmk_len &&
295 		      os_memcmp(pmk, entry->pmk, pmk_len) == 0))) {
296 			wpa_printf(MSG_DEBUG, "RSN: Flush PMKSA cache entry "
297 				   "for " MACSTR, MAC2STR(entry->aa));
298 			if (prev)
299 				prev->next = entry->next;
300 			else
301 				pmksa->pmksa = entry->next;
302 			tmp = entry;
303 			entry = entry->next;
304 			pmksa_cache_free_entry(pmksa, tmp, PMKSA_FREE);
305 			removed++;
306 		} else {
307 			prev = entry;
308 			entry = entry->next;
309 		}
310 	}
311 	if (removed)
312 		pmksa_cache_set_expiration(pmksa);
313 }
314 
315 
316 /**
317  * pmksa_cache_deinit - Free all entries in PMKSA cache
318  * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
319  */
320 void pmksa_cache_deinit(struct rsn_pmksa_cache *pmksa)
321 {
322 	struct rsn_pmksa_cache_entry *entry, *prev;
323 
324 	if (pmksa == NULL)
325 		return;
326 
327 	entry = pmksa->pmksa;
328 	pmksa->pmksa = NULL;
329 	while (entry) {
330 		prev = entry;
331 		entry = entry->next;
332 		os_free(prev);
333 	}
334 	pmksa_cache_set_expiration(pmksa);
335 	os_free(pmksa);
336 }
337 
338 
339 /**
340  * pmksa_cache_get - Fetch a PMKSA cache entry
341  * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
342  * @aa: Authenticator address or %NULL to match any
343  * @pmkid: PMKID or %NULL to match any
344  * @network_ctx: Network context or %NULL to match any
345  * @akmp: Specific AKMP to search for or 0 for any
346  * Returns: Pointer to PMKSA cache entry or %NULL if no match was found
347  */
348 struct rsn_pmksa_cache_entry * pmksa_cache_get(struct rsn_pmksa_cache *pmksa,
349 					       const u8 *aa, const u8 *pmkid,
350 					       const void *network_ctx,
351 					       int akmp)
352 {
353 	struct rsn_pmksa_cache_entry *entry = pmksa->pmksa;
354 	while (entry) {
355 		if ((aa == NULL || os_memcmp(entry->aa, aa, ETH_ALEN) == 0) &&
356 		    (pmkid == NULL ||
357 		     os_memcmp(entry->pmkid, pmkid, PMKID_LEN) == 0) &&
358 		    (!akmp || akmp == entry->akmp) &&
359 		    (network_ctx == NULL || network_ctx == entry->network_ctx))
360 			return entry;
361 		entry = entry->next;
362 	}
363 	return NULL;
364 }
365 
366 
367 static struct rsn_pmksa_cache_entry *
368 pmksa_cache_clone_entry(struct rsn_pmksa_cache *pmksa,
369 			const struct rsn_pmksa_cache_entry *old_entry,
370 			const u8 *aa)
371 {
372 	struct rsn_pmksa_cache_entry *new_entry;
373 	os_time_t old_expiration = old_entry->expiration;
374 
375 	new_entry = pmksa_cache_add(pmksa, old_entry->pmk, old_entry->pmk_len,
376 				    NULL, NULL, 0,
377 				    aa, pmksa->sm->own_addr,
378 				    old_entry->network_ctx, old_entry->akmp,
379 				    old_entry->fils_cache_id_set ?
380 				    old_entry->fils_cache_id : NULL);
381 	if (new_entry == NULL)
382 		return NULL;
383 
384 	/* TODO: reorder entries based on expiration time? */
385 	new_entry->expiration = old_expiration;
386 	new_entry->opportunistic = 1;
387 
388 	return new_entry;
389 }
390 
391 
392 /**
393  * pmksa_cache_get_opportunistic - Try to get an opportunistic PMKSA entry
394  * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
395  * @network_ctx: Network configuration context
396  * @aa: Authenticator address for the new AP
397  * @akmp: Specific AKMP to search for or 0 for any
398  * Returns: Pointer to a new PMKSA cache entry or %NULL if not available
399  *
400  * Try to create a new PMKSA cache entry opportunistically by guessing that the
401  * new AP is sharing the same PMK as another AP that has the same SSID and has
402  * already an entry in PMKSA cache.
403  */
404 struct rsn_pmksa_cache_entry *
405 pmksa_cache_get_opportunistic(struct rsn_pmksa_cache *pmksa, void *network_ctx,
406 			      const u8 *aa, int akmp)
407 {
408 	struct rsn_pmksa_cache_entry *entry = pmksa->pmksa;
409 
410 	wpa_printf(MSG_DEBUG, "RSN: Consider " MACSTR " for OKC", MAC2STR(aa));
411 	if (network_ctx == NULL)
412 		return NULL;
413 	while (entry) {
414 		if (entry->network_ctx == network_ctx &&
415 		    (!akmp || entry->akmp == akmp)) {
416 			entry = pmksa_cache_clone_entry(pmksa, entry, aa);
417 			if (entry) {
418 				wpa_printf(MSG_DEBUG, "RSN: added "
419 					   "opportunistic PMKSA cache entry "
420 					   "for " MACSTR, MAC2STR(aa));
421 			}
422 			return entry;
423 		}
424 		entry = entry->next;
425 	}
426 	return NULL;
427 }
428 
429 
430 static struct rsn_pmksa_cache_entry *
431 pmksa_cache_get_fils_cache_id(struct rsn_pmksa_cache *pmksa,
432 			      const void *network_ctx, const u8 *cache_id)
433 {
434 	struct rsn_pmksa_cache_entry *entry;
435 
436 	for (entry = pmksa->pmksa; entry; entry = entry->next) {
437 		if (network_ctx == entry->network_ctx &&
438 		    entry->fils_cache_id_set &&
439 		    os_memcmp(cache_id, entry->fils_cache_id,
440 			      FILS_CACHE_ID_LEN) == 0)
441 			return entry;
442 	}
443 
444 	return NULL;
445 }
446 
447 
448 /**
449  * pmksa_cache_get_current - Get the current used PMKSA entry
450  * @sm: Pointer to WPA state machine data from wpa_sm_init()
451  * Returns: Pointer to the current PMKSA cache entry or %NULL if not available
452  */
453 struct rsn_pmksa_cache_entry * pmksa_cache_get_current(struct wpa_sm *sm)
454 {
455 	if (sm == NULL)
456 		return NULL;
457 	return sm->cur_pmksa;
458 }
459 
460 
461 /**
462  * pmksa_cache_clear_current - Clear the current PMKSA entry selection
463  * @sm: Pointer to WPA state machine data from wpa_sm_init()
464  */
465 void pmksa_cache_clear_current(struct wpa_sm *sm)
466 {
467 	if (sm == NULL)
468 		return;
469 	sm->cur_pmksa = NULL;
470 }
471 
472 
473 /**
474  * pmksa_cache_set_current - Set the current PMKSA entry selection
475  * @sm: Pointer to WPA state machine data from wpa_sm_init()
476  * @pmkid: PMKID for selecting PMKSA or %NULL if not used
477  * @bssid: BSSID for PMKSA or %NULL if not used
478  * @network_ctx: Network configuration context
479  * @try_opportunistic: Whether to allow opportunistic PMKSA caching
480  * @fils_cache_id: Pointer to FILS Cache Identifier or %NULL if not used
481  * Returns: 0 if PMKSA was found or -1 if no matching entry was found
482  */
483 int pmksa_cache_set_current(struct wpa_sm *sm, const u8 *pmkid,
484 			    const u8 *bssid, void *network_ctx,
485 			    int try_opportunistic, const u8 *fils_cache_id,
486 			    int akmp)
487 {
488 	struct rsn_pmksa_cache *pmksa = sm->pmksa;
489 	wpa_printf(MSG_DEBUG, "RSN: PMKSA cache search - network_ctx=%p "
490 		   "try_opportunistic=%d akmp=0x%x",
491 		   network_ctx, try_opportunistic, akmp);
492 	if (pmkid)
493 		wpa_hexdump(MSG_DEBUG, "RSN: Search for PMKID",
494 			    pmkid, PMKID_LEN);
495 	if (bssid)
496 		wpa_printf(MSG_DEBUG, "RSN: Search for BSSID " MACSTR,
497 			   MAC2STR(bssid));
498 	if (fils_cache_id)
499 		wpa_printf(MSG_DEBUG,
500 			   "RSN: Search for FILS Cache Identifier %02x%02x",
501 			   fils_cache_id[0], fils_cache_id[1]);
502 
503 	sm->cur_pmksa = NULL;
504 	if (pmkid)
505 		sm->cur_pmksa = pmksa_cache_get(pmksa, NULL, pmkid,
506 						network_ctx, akmp);
507 	if (sm->cur_pmksa == NULL && bssid)
508 		sm->cur_pmksa = pmksa_cache_get(pmksa, bssid, NULL,
509 						network_ctx, akmp);
510 	if (sm->cur_pmksa == NULL && try_opportunistic && bssid)
511 		sm->cur_pmksa = pmksa_cache_get_opportunistic(pmksa,
512 							      network_ctx,
513 							      bssid, akmp);
514 	if (sm->cur_pmksa == NULL && fils_cache_id)
515 		sm->cur_pmksa = pmksa_cache_get_fils_cache_id(pmksa,
516 							      network_ctx,
517 							      fils_cache_id);
518 	if (sm->cur_pmksa) {
519 		wpa_hexdump(MSG_DEBUG, "RSN: PMKSA cache entry found - PMKID",
520 			    sm->cur_pmksa->pmkid, PMKID_LEN);
521 		return 0;
522 	}
523 	wpa_printf(MSG_DEBUG, "RSN: No PMKSA cache entry found");
524 	return -1;
525 }
526 
527 
528 /**
529  * pmksa_cache_list - Dump text list of entries in PMKSA cache
530  * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
531  * @buf: Buffer for the list
532  * @len: Length of the buffer
533  * Returns: number of bytes written to buffer
534  *
535  * This function is used to generate a text format representation of the
536  * current PMKSA cache contents for the ctrl_iface PMKSA command.
537  */
538 int pmksa_cache_list(struct rsn_pmksa_cache *pmksa, char *buf, size_t len)
539 {
540 	int i, ret;
541 	char *pos = buf;
542 	struct rsn_pmksa_cache_entry *entry;
543 	struct os_reltime now;
544 	int cache_id_used = 0;
545 
546 	for (entry = pmksa->pmksa; entry; entry = entry->next) {
547 		if (entry->fils_cache_id_set) {
548 			cache_id_used = 1;
549 			break;
550 		}
551 	}
552 
553 	os_get_reltime(&now);
554 	ret = os_snprintf(pos, buf + len - pos,
555 			  "Index / AA / PMKID / expiration (in seconds) / "
556 			  "opportunistic%s\n",
557 			  cache_id_used ? " / FILS Cache Identifier" : "");
558 	if (os_snprintf_error(buf + len - pos, ret))
559 		return pos - buf;
560 	pos += ret;
561 	i = 0;
562 	entry = pmksa->pmksa;
563 	while (entry) {
564 		i++;
565 		ret = os_snprintf(pos, buf + len - pos, "%d " MACSTR " ",
566 				  i, MAC2STR(entry->aa));
567 		if (os_snprintf_error(buf + len - pos, ret))
568 			return pos - buf;
569 		pos += ret;
570 		pos += wpa_snprintf_hex(pos, buf + len - pos, entry->pmkid,
571 					PMKID_LEN);
572 		ret = os_snprintf(pos, buf + len - pos, " %d %d",
573 				  (int) (entry->expiration - now.sec),
574 				  entry->opportunistic);
575 		if (os_snprintf_error(buf + len - pos, ret))
576 			return pos - buf;
577 		pos += ret;
578 		if (entry->fils_cache_id_set) {
579 			ret = os_snprintf(pos, buf + len - pos, " %02x%02x",
580 					  entry->fils_cache_id[0],
581 					  entry->fils_cache_id[1]);
582 			if (os_snprintf_error(buf + len - pos, ret))
583 				return pos - buf;
584 			pos += ret;
585 		}
586 		ret = os_snprintf(pos, buf + len - pos, "\n");
587 		if (os_snprintf_error(buf + len - pos, ret))
588 			return pos - buf;
589 		pos += ret;
590 		entry = entry->next;
591 	}
592 	return pos - buf;
593 }
594 
595 
596 struct rsn_pmksa_cache_entry * pmksa_cache_head(struct rsn_pmksa_cache *pmksa)
597 {
598 	return pmksa->pmksa;
599 }
600 
601 
602 /**
603  * pmksa_cache_init - Initialize PMKSA cache
604  * @free_cb: Callback function to be called when a PMKSA cache entry is freed
605  * @ctx: Context pointer for free_cb function
606  * @sm: Pointer to WPA state machine data from wpa_sm_init()
607  * Returns: Pointer to PMKSA cache data or %NULL on failure
608  */
609 struct rsn_pmksa_cache *
610 pmksa_cache_init(void (*free_cb)(struct rsn_pmksa_cache_entry *entry,
611 				 void *ctx, enum pmksa_free_reason reason),
612 		 void *ctx, struct wpa_sm *sm)
613 {
614 	struct rsn_pmksa_cache *pmksa;
615 
616 	pmksa = os_zalloc(sizeof(*pmksa));
617 	if (pmksa) {
618 		pmksa->free_cb = free_cb;
619 		pmksa->ctx = ctx;
620 		pmksa->sm = sm;
621 	}
622 
623 	return pmksa;
624 }
625 
626 #endif /* IEEE8021X_EAPOL */
627