Added WirelessManager, a port of wpa_supplicant.
[AROS.git] / workbench / network / WirelessManager / src / rsn_supp / pmksa_cache.c
blobcac8c83e6eeb4569794d9d2b3294686242484b5c
1 /*
2 * WPA Supplicant - RSN PMKSA cache
3 * Copyright (c) 2004-2008, Jouni Malinen <j@w1.fi>
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.
9 * Alternatively, this software may be distributed under the terms of BSD
10 * license.
12 * See README and COPYING for more details.
15 #include "includes.h"
17 #include "common.h"
18 #include "eloop.h"
19 #include "eapol_supp/eapol_supp_sm.h"
20 #include "wpa.h"
21 #include "wpa_i.h"
22 #include "pmksa_cache.h"
24 #if defined(IEEE8021X_EAPOL) && !defined(CONFIG_NO_WPA2)
26 static const int pmksa_cache_max_entries = 32;
28 struct rsn_pmksa_cache {
29 struct rsn_pmksa_cache_entry *pmksa; /* PMKSA cache */
30 int pmksa_count; /* number of entries in PMKSA cache */
31 struct wpa_sm *sm; /* TODO: get rid of this reference(?) */
33 void (*free_cb)(struct rsn_pmksa_cache_entry *entry, void *ctx,
34 int replace);
35 void *ctx;
39 static void pmksa_cache_set_expiration(struct rsn_pmksa_cache *pmksa);
42 static void _pmksa_cache_free_entry(struct rsn_pmksa_cache_entry *entry)
44 os_free(entry);
48 static void pmksa_cache_free_entry(struct rsn_pmksa_cache *pmksa,
49 struct rsn_pmksa_cache_entry *entry,
50 int replace)
52 pmksa->pmksa_count--;
53 pmksa->free_cb(entry, pmksa->ctx, replace);
54 _pmksa_cache_free_entry(entry);
58 static void pmksa_cache_expire(void *eloop_ctx, void *timeout_ctx)
60 struct rsn_pmksa_cache *pmksa = eloop_ctx;
61 struct os_time now;
63 os_get_time(&now);
64 while (pmksa->pmksa && pmksa->pmksa->expiration <= now.sec) {
65 struct rsn_pmksa_cache_entry *entry = pmksa->pmksa;
66 pmksa->pmksa = entry->next;
67 wpa_printf(MSG_DEBUG, "RSN: expired PMKSA cache entry for "
68 MACSTR, MAC2STR(entry->aa));
69 pmksa_cache_free_entry(pmksa, entry, 0);
72 pmksa_cache_set_expiration(pmksa);
76 static void pmksa_cache_reauth(void *eloop_ctx, void *timeout_ctx)
78 struct rsn_pmksa_cache *pmksa = eloop_ctx;
79 pmksa->sm->cur_pmksa = NULL;
80 eapol_sm_request_reauth(pmksa->sm->eapol);
84 static void pmksa_cache_set_expiration(struct rsn_pmksa_cache *pmksa)
86 int sec;
87 struct rsn_pmksa_cache_entry *entry;
88 struct os_time now;
90 eloop_cancel_timeout(pmksa_cache_expire, pmksa, NULL);
91 eloop_cancel_timeout(pmksa_cache_reauth, pmksa, NULL);
92 if (pmksa->pmksa == NULL)
93 return;
94 os_get_time(&now);
95 sec = pmksa->pmksa->expiration - now.sec;
96 if (sec < 0)
97 sec = 0;
98 eloop_register_timeout(sec + 1, 0, pmksa_cache_expire, pmksa, NULL);
100 entry = pmksa->sm->cur_pmksa ? pmksa->sm->cur_pmksa :
101 pmksa_cache_get(pmksa, pmksa->sm->bssid, NULL);
102 if (entry) {
103 sec = pmksa->pmksa->reauth_time - now.sec;
104 if (sec < 0)
105 sec = 0;
106 eloop_register_timeout(sec, 0, pmksa_cache_reauth, pmksa,
107 NULL);
113 * pmksa_cache_add - Add a PMKSA cache entry
114 * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
115 * @pmk: The new pairwise master key
116 * @pmk_len: PMK length in bytes, usually PMK_LEN (32)
117 * @aa: Authenticator address
118 * @spa: Supplicant address
119 * @network_ctx: Network configuration context for this PMK
120 * @akmp: WPA_KEY_MGMT_* used in key derivation
121 * Returns: Pointer to the added PMKSA cache entry or %NULL on error
123 * This function create a PMKSA entry for a new PMK and adds it to the PMKSA
124 * cache. If an old entry is already in the cache for the same Authenticator,
125 * this entry will be replaced with the new entry. PMKID will be calculated
126 * based on the PMK and the driver interface is notified of the new PMKID.
128 struct rsn_pmksa_cache_entry *
129 pmksa_cache_add(struct rsn_pmksa_cache *pmksa, const u8 *pmk, size_t pmk_len,
130 const u8 *aa, const u8 *spa, void *network_ctx, int akmp)
132 struct rsn_pmksa_cache_entry *entry, *pos, *prev;
133 struct os_time now;
135 if (pmk_len > PMK_LEN)
136 return NULL;
138 entry = os_zalloc(sizeof(*entry));
139 if (entry == NULL)
140 return NULL;
141 os_memcpy(entry->pmk, pmk, pmk_len);
142 entry->pmk_len = pmk_len;
143 rsn_pmkid(pmk, pmk_len, aa, spa, entry->pmkid,
144 wpa_key_mgmt_sha256(akmp));
145 os_get_time(&now);
146 entry->expiration = now.sec + pmksa->sm->dot11RSNAConfigPMKLifetime;
147 entry->reauth_time = now.sec + pmksa->sm->dot11RSNAConfigPMKLifetime *
148 pmksa->sm->dot11RSNAConfigPMKReauthThreshold / 100;
149 entry->akmp = akmp;
150 os_memcpy(entry->aa, aa, ETH_ALEN);
151 entry->network_ctx = network_ctx;
153 /* Replace an old entry for the same Authenticator (if found) with the
154 * new entry */
155 pos = pmksa->pmksa;
156 prev = NULL;
157 while (pos) {
158 if (os_memcmp(aa, pos->aa, ETH_ALEN) == 0) {
159 if (pos->pmk_len == pmk_len &&
160 os_memcmp(pos->pmk, pmk, pmk_len) == 0 &&
161 os_memcmp(pos->pmkid, entry->pmkid, PMKID_LEN) ==
162 0) {
163 wpa_printf(MSG_DEBUG, "WPA: reusing previous "
164 "PMKSA entry");
165 os_free(entry);
166 return pos;
168 if (prev == NULL)
169 pmksa->pmksa = pos->next;
170 else
171 prev->next = pos->next;
172 if (pos == pmksa->sm->cur_pmksa) {
173 /* We are about to replace the current PMKSA
174 * cache entry. This happens when the PMKSA
175 * caching attempt fails, so we don't want to
176 * force pmksa_cache_free_entry() to disconnect
177 * at this point. Let's just make sure the old
178 * PMKSA cache entry will not be used in the
179 * future.
181 wpa_printf(MSG_DEBUG, "RSN: replacing current "
182 "PMKSA entry");
183 pmksa->sm->cur_pmksa = NULL;
185 wpa_printf(MSG_DEBUG, "RSN: Replace PMKSA entry for "
186 "the current AP");
187 pmksa_cache_free_entry(pmksa, pos, 1);
188 break;
190 prev = pos;
191 pos = pos->next;
194 if (pmksa->pmksa_count >= pmksa_cache_max_entries && pmksa->pmksa) {
195 /* Remove the oldest entry to make room for the new entry */
196 pos = pmksa->pmksa;
197 pmksa->pmksa = pos->next;
198 wpa_printf(MSG_DEBUG, "RSN: removed the oldest PMKSA cache "
199 "entry (for " MACSTR ") to make room for new one",
200 MAC2STR(pos->aa));
201 wpa_sm_remove_pmkid(pmksa->sm, pos->aa, pos->pmkid);
202 pmksa_cache_free_entry(pmksa, pos, 0);
205 /* Add the new entry; order by expiration time */
206 pos = pmksa->pmksa;
207 prev = NULL;
208 while (pos) {
209 if (pos->expiration > entry->expiration)
210 break;
211 prev = pos;
212 pos = pos->next;
214 if (prev == NULL) {
215 entry->next = pmksa->pmksa;
216 pmksa->pmksa = entry;
217 pmksa_cache_set_expiration(pmksa);
218 } else {
219 entry->next = prev->next;
220 prev->next = entry;
222 pmksa->pmksa_count++;
223 wpa_printf(MSG_DEBUG, "RSN: added PMKSA cache entry for " MACSTR,
224 MAC2STR(entry->aa));
225 wpa_sm_add_pmkid(pmksa->sm, entry->aa, entry->pmkid);
227 return entry;
232 * pmksa_cache_deinit - Free all entries in PMKSA cache
233 * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
235 void pmksa_cache_deinit(struct rsn_pmksa_cache *pmksa)
237 struct rsn_pmksa_cache_entry *entry, *prev;
239 if (pmksa == NULL)
240 return;
242 entry = pmksa->pmksa;
243 pmksa->pmksa = NULL;
244 while (entry) {
245 prev = entry;
246 entry = entry->next;
247 os_free(prev);
249 pmksa_cache_set_expiration(pmksa);
250 os_free(pmksa);
255 * pmksa_cache_get - Fetch a PMKSA cache entry
256 * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
257 * @aa: Authenticator address or %NULL to match any
258 * @pmkid: PMKID or %NULL to match any
259 * Returns: Pointer to PMKSA cache entry or %NULL if no match was found
261 struct rsn_pmksa_cache_entry * pmksa_cache_get(struct rsn_pmksa_cache *pmksa,
262 const u8 *aa, const u8 *pmkid)
264 struct rsn_pmksa_cache_entry *entry = pmksa->pmksa;
265 while (entry) {
266 if ((aa == NULL || os_memcmp(entry->aa, aa, ETH_ALEN) == 0) &&
267 (pmkid == NULL ||
268 os_memcmp(entry->pmkid, pmkid, PMKID_LEN) == 0))
269 return entry;
270 entry = entry->next;
272 return NULL;
277 * pmksa_cache_notify_reconfig - Reconfiguration notification for PMKSA cache
278 * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
280 * Clear references to old data structures when wpa_supplicant is reconfigured.
282 void pmksa_cache_notify_reconfig(struct rsn_pmksa_cache *pmksa)
284 struct rsn_pmksa_cache_entry *entry = pmksa->pmksa;
285 while (entry) {
286 entry->network_ctx = NULL;
287 entry = entry->next;
292 static struct rsn_pmksa_cache_entry *
293 pmksa_cache_clone_entry(struct rsn_pmksa_cache *pmksa,
294 const struct rsn_pmksa_cache_entry *old_entry,
295 const u8 *aa)
297 struct rsn_pmksa_cache_entry *new_entry;
299 new_entry = pmksa_cache_add(pmksa, old_entry->pmk, old_entry->pmk_len,
300 aa, pmksa->sm->own_addr,
301 old_entry->network_ctx, old_entry->akmp);
302 if (new_entry == NULL)
303 return NULL;
305 /* TODO: reorder entries based on expiration time? */
306 new_entry->expiration = old_entry->expiration;
307 new_entry->opportunistic = 1;
309 return new_entry;
314 * pmksa_cache_get_opportunistic - Try to get an opportunistic PMKSA entry
315 * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
316 * @network_ctx: Network configuration context
317 * @aa: Authenticator address for the new AP
318 * Returns: Pointer to a new PMKSA cache entry or %NULL if not available
320 * Try to create a new PMKSA cache entry opportunistically by guessing that the
321 * new AP is sharing the same PMK as another AP that has the same SSID and has
322 * already an entry in PMKSA cache.
324 struct rsn_pmksa_cache_entry *
325 pmksa_cache_get_opportunistic(struct rsn_pmksa_cache *pmksa, void *network_ctx,
326 const u8 *aa)
328 struct rsn_pmksa_cache_entry *entry = pmksa->pmksa;
330 if (network_ctx == NULL)
331 return NULL;
332 while (entry) {
333 if (entry->network_ctx == network_ctx) {
334 entry = pmksa_cache_clone_entry(pmksa, entry, aa);
335 if (entry) {
336 wpa_printf(MSG_DEBUG, "RSN: added "
337 "opportunistic PMKSA cache entry "
338 "for " MACSTR, MAC2STR(aa));
340 return entry;
342 entry = entry->next;
344 return NULL;
349 * pmksa_cache_get_current - Get the current used PMKSA entry
350 * @sm: Pointer to WPA state machine data from wpa_sm_init()
351 * Returns: Pointer to the current PMKSA cache entry or %NULL if not available
353 struct rsn_pmksa_cache_entry * pmksa_cache_get_current(struct wpa_sm *sm)
355 if (sm == NULL)
356 return NULL;
357 return sm->cur_pmksa;
362 * pmksa_cache_clear_current - Clear the current PMKSA entry selection
363 * @sm: Pointer to WPA state machine data from wpa_sm_init()
365 void pmksa_cache_clear_current(struct wpa_sm *sm)
367 if (sm == NULL)
368 return;
369 sm->cur_pmksa = NULL;
374 * pmksa_cache_set_current - Set the current PMKSA entry selection
375 * @sm: Pointer to WPA state machine data from wpa_sm_init()
376 * @pmkid: PMKID for selecting PMKSA or %NULL if not used
377 * @bssid: BSSID for PMKSA or %NULL if not used
378 * @network_ctx: Network configuration context
379 * @try_opportunistic: Whether to allow opportunistic PMKSA caching
380 * Returns: 0 if PMKSA was found or -1 if no matching entry was found
382 int pmksa_cache_set_current(struct wpa_sm *sm, const u8 *pmkid,
383 const u8 *bssid, void *network_ctx,
384 int try_opportunistic)
386 struct rsn_pmksa_cache *pmksa = sm->pmksa;
387 sm->cur_pmksa = NULL;
388 if (pmkid)
389 sm->cur_pmksa = pmksa_cache_get(pmksa, NULL, pmkid);
390 if (sm->cur_pmksa == NULL && bssid)
391 sm->cur_pmksa = pmksa_cache_get(pmksa, bssid, NULL);
392 if (sm->cur_pmksa == NULL && try_opportunistic && bssid)
393 sm->cur_pmksa = pmksa_cache_get_opportunistic(pmksa,
394 network_ctx,
395 bssid);
396 if (sm->cur_pmksa) {
397 wpa_hexdump(MSG_DEBUG, "RSN: PMKID",
398 sm->cur_pmksa->pmkid, PMKID_LEN);
399 return 0;
401 return -1;
406 * pmksa_cache_list - Dump text list of entries in PMKSA cache
407 * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
408 * @buf: Buffer for the list
409 * @len: Length of the buffer
410 * Returns: number of bytes written to buffer
412 * This function is used to generate a text format representation of the
413 * current PMKSA cache contents for the ctrl_iface PMKSA command.
415 int pmksa_cache_list(struct rsn_pmksa_cache *pmksa, char *buf, size_t len)
417 int i, ret;
418 char *pos = buf;
419 struct rsn_pmksa_cache_entry *entry;
420 struct os_time now;
422 os_get_time(&now);
423 ret = os_snprintf(pos, buf + len - pos,
424 "Index / AA / PMKID / expiration (in seconds) / "
425 "opportunistic\n");
426 if (ret < 0 || ret >= buf + len - pos)
427 return pos - buf;
428 pos += ret;
429 i = 0;
430 entry = pmksa->pmksa;
431 while (entry) {
432 i++;
433 ret = os_snprintf(pos, buf + len - pos, "%d " MACSTR " ",
434 i, MAC2STR(entry->aa));
435 if (ret < 0 || ret >= buf + len - pos)
436 return pos - buf;
437 pos += ret;
438 pos += wpa_snprintf_hex(pos, buf + len - pos, entry->pmkid,
439 PMKID_LEN);
440 ret = os_snprintf(pos, buf + len - pos, " %d %d\n",
441 (int) (entry->expiration - now.sec),
442 entry->opportunistic);
443 if (ret < 0 || ret >= buf + len - pos)
444 return pos - buf;
445 pos += ret;
446 entry = entry->next;
448 return pos - buf;
453 * pmksa_cache_init - Initialize PMKSA cache
454 * @free_cb: Callback function to be called when a PMKSA cache entry is freed
455 * @ctx: Context pointer for free_cb function
456 * @sm: Pointer to WPA state machine data from wpa_sm_init()
457 * Returns: Pointer to PMKSA cache data or %NULL on failure
459 struct rsn_pmksa_cache *
460 pmksa_cache_init(void (*free_cb)(struct rsn_pmksa_cache_entry *entry,
461 void *ctx, int replace),
462 void *ctx, struct wpa_sm *sm)
464 struct rsn_pmksa_cache *pmksa;
466 pmksa = os_zalloc(sizeof(*pmksa));
467 if (pmksa) {
468 pmksa->free_cb = free_cb;
469 pmksa->ctx = ctx;
470 pmksa->sm = sm;
473 return pmksa;
476 #endif /* IEEE8021X_EAPOL and !CONFIG_NO_WPA2 */