Commit | Line | Data |
---|---|---|
1f5a7e47 JB |
1 | /* |
2 | * Copyright 2002-2005, Instant802 Networks, Inc. | |
3 | * Copyright 2005-2006, Devicescape Software, Inc. | |
4 | * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> | |
3b96766f | 5 | * Copyright 2007-2008 Johannes Berg <johannes@sipsolutions.net> |
1f5a7e47 JB |
6 | * |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License version 2 as | |
9 | * published by the Free Software Foundation. | |
10 | */ | |
11 | ||
11a843b7 JB |
12 | #include <linux/if_ether.h> |
13 | #include <linux/etherdevice.h> | |
14 | #include <linux/list.h> | |
d4e46a3d | 15 | #include <linux/rcupdate.h> |
db4d1169 | 16 | #include <linux/rtnetlink.h> |
5a0e3ad6 | 17 | #include <linux/slab.h> |
1f5a7e47 JB |
18 | #include <net/mac80211.h> |
19 | #include "ieee80211_i.h" | |
24487981 | 20 | #include "driver-ops.h" |
1f5a7e47 JB |
21 | #include "debugfs_key.h" |
22 | #include "aes_ccm.h" | |
3cfcf6ac | 23 | #include "aes_cmac.h" |
1f5a7e47 | 24 | |
11a843b7 | 25 | |
dbbea671 JB |
26 | /** |
27 | * DOC: Key handling basics | |
11a843b7 JB |
28 | * |
29 | * Key handling in mac80211 is done based on per-interface (sub_if_data) | |
30 | * keys and per-station keys. Since each station belongs to an interface, | |
31 | * each station key also belongs to that interface. | |
32 | * | |
33 | * Hardware acceleration is done on a best-effort basis, for each key | |
34 | * that is eligible the hardware is asked to enable that key but if | |
35 | * it cannot do that they key is simply kept for software encryption. | |
36 | * There is currently no way of knowing this except by looking into | |
37 | * debugfs. | |
38 | * | |
ad0e2b5a | 39 | * All key operations are protected internally. |
db4d1169 | 40 | * |
3b96766f JB |
41 | * Within mac80211, key references are, just as STA structure references, |
42 | * protected by RCU. Note, however, that some things are unprotected, | |
43 | * namely the key->sta dereferences within the hardware acceleration | |
ad0e2b5a JB |
44 | * functions. This means that sta_info_destroy() must remove the key |
45 | * which waits for an RCU grace period. | |
11a843b7 JB |
46 | */ |
47 | ||
48 | static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF }; | |
11a843b7 | 49 | |
ad0e2b5a | 50 | static void assert_key_lock(struct ieee80211_local *local) |
3b96766f | 51 | { |
ad0e2b5a | 52 | WARN_ON(!mutex_is_locked(&local->key_mtx)); |
3b96766f JB |
53 | } |
54 | ||
dc822b5d | 55 | static struct ieee80211_sta *get_sta_for_key(struct ieee80211_key *key) |
11a843b7 | 56 | { |
11a843b7 | 57 | if (key->sta) |
dc822b5d | 58 | return &key->sta->sta; |
11a843b7 | 59 | |
dc822b5d | 60 | return NULL; |
11a843b7 JB |
61 | } |
62 | ||
63 | static void ieee80211_key_enable_hw_accel(struct ieee80211_key *key) | |
64 | { | |
dc822b5d JB |
65 | struct ieee80211_sub_if_data *sdata; |
66 | struct ieee80211_sta *sta; | |
11a843b7 JB |
67 | int ret; |
68 | ||
3b96766f JB |
69 | might_sleep(); |
70 | ||
11a843b7 JB |
71 | if (!key->local->ops->set_key) |
72 | return; | |
73 | ||
ad0e2b5a JB |
74 | assert_key_lock(key->local); |
75 | ||
dc822b5d JB |
76 | sta = get_sta_for_key(key); |
77 | ||
78 | sdata = key->sdata; | |
79 | if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) | |
80 | sdata = container_of(sdata->bss, | |
81 | struct ieee80211_sub_if_data, | |
82 | u.ap); | |
11a843b7 | 83 | |
12375ef9 | 84 | ret = drv_set_key(key->local, SET_KEY, sdata, sta, &key->conf); |
11a843b7 | 85 | |
ad0e2b5a | 86 | if (!ret) |
11a843b7 JB |
87 | key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE; |
88 | ||
89 | if (ret && ret != -ENOSPC && ret != -EOPNOTSUPP) | |
0fb9a9ec JP |
90 | wiphy_err(key->local->hw.wiphy, |
91 | "failed to set key (%d, %pM) to hardware (%d)\n", | |
92 | key->conf.keyidx, sta ? sta->addr : bcast_addr, ret); | |
11a843b7 JB |
93 | } |
94 | ||
95 | static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key) | |
96 | { | |
dc822b5d JB |
97 | struct ieee80211_sub_if_data *sdata; |
98 | struct ieee80211_sta *sta; | |
11a843b7 JB |
99 | int ret; |
100 | ||
3b96766f JB |
101 | might_sleep(); |
102 | ||
db4d1169 | 103 | if (!key || !key->local->ops->set_key) |
11a843b7 JB |
104 | return; |
105 | ||
ad0e2b5a JB |
106 | assert_key_lock(key->local); |
107 | ||
108 | if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) | |
11a843b7 JB |
109 | return; |
110 | ||
dc822b5d JB |
111 | sta = get_sta_for_key(key); |
112 | sdata = key->sdata; | |
113 | ||
114 | if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) | |
115 | sdata = container_of(sdata->bss, | |
116 | struct ieee80211_sub_if_data, | |
117 | u.ap); | |
11a843b7 | 118 | |
12375ef9 | 119 | ret = drv_set_key(key->local, DISABLE_KEY, sdata, |
24487981 | 120 | sta, &key->conf); |
11a843b7 JB |
121 | |
122 | if (ret) | |
0fb9a9ec JP |
123 | wiphy_err(key->local->hw.wiphy, |
124 | "failed to remove key (%d, %pM) from hardware (%d)\n", | |
125 | key->conf.keyidx, sta ? sta->addr : bcast_addr, ret); | |
11a843b7 | 126 | |
3b96766f | 127 | key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE; |
3b96766f JB |
128 | } |
129 | ||
130 | static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, | |
131 | int idx) | |
132 | { | |
133 | struct ieee80211_key *key = NULL; | |
134 | ||
ad0e2b5a JB |
135 | assert_key_lock(sdata->local); |
136 | ||
3b96766f JB |
137 | if (idx >= 0 && idx < NUM_DEFAULT_KEYS) |
138 | key = sdata->keys[idx]; | |
139 | ||
140 | rcu_assign_pointer(sdata->default_key, key); | |
141 | ||
ad0e2b5a JB |
142 | if (key) { |
143 | ieee80211_debugfs_key_remove_default(key->sdata); | |
144 | ieee80211_debugfs_key_add_default(key->sdata); | |
145 | } | |
3b96766f JB |
146 | } |
147 | ||
148 | void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx) | |
149 | { | |
ad0e2b5a | 150 | mutex_lock(&sdata->local->key_mtx); |
3b96766f | 151 | __ieee80211_set_default_key(sdata, idx); |
ad0e2b5a | 152 | mutex_unlock(&sdata->local->key_mtx); |
3b96766f JB |
153 | } |
154 | ||
3cfcf6ac JM |
155 | static void |
156 | __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx) | |
157 | { | |
158 | struct ieee80211_key *key = NULL; | |
159 | ||
ad0e2b5a JB |
160 | assert_key_lock(sdata->local); |
161 | ||
3cfcf6ac JM |
162 | if (idx >= NUM_DEFAULT_KEYS && |
163 | idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS) | |
164 | key = sdata->keys[idx]; | |
165 | ||
166 | rcu_assign_pointer(sdata->default_mgmt_key, key); | |
167 | ||
ad0e2b5a JB |
168 | if (key) { |
169 | ieee80211_debugfs_key_remove_mgmt_default(key->sdata); | |
170 | ieee80211_debugfs_key_add_mgmt_default(key->sdata); | |
171 | } | |
3cfcf6ac JM |
172 | } |
173 | ||
174 | void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, | |
175 | int idx) | |
176 | { | |
ad0e2b5a | 177 | mutex_lock(&sdata->local->key_mtx); |
3cfcf6ac | 178 | __ieee80211_set_default_mgmt_key(sdata, idx); |
ad0e2b5a | 179 | mutex_unlock(&sdata->local->key_mtx); |
3cfcf6ac JM |
180 | } |
181 | ||
3b96766f JB |
182 | |
183 | static void __ieee80211_key_replace(struct ieee80211_sub_if_data *sdata, | |
184 | struct sta_info *sta, | |
185 | struct ieee80211_key *old, | |
186 | struct ieee80211_key *new) | |
187 | { | |
3cfcf6ac | 188 | int idx, defkey, defmgmtkey; |
3b96766f JB |
189 | |
190 | if (new) | |
191 | list_add(&new->list, &sdata->key_list); | |
192 | ||
193 | if (sta) { | |
194 | rcu_assign_pointer(sta->key, new); | |
195 | } else { | |
196 | WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx); | |
197 | ||
198 | if (old) | |
199 | idx = old->conf.keyidx; | |
200 | else | |
201 | idx = new->conf.keyidx; | |
202 | ||
203 | defkey = old && sdata->default_key == old; | |
3cfcf6ac | 204 | defmgmtkey = old && sdata->default_mgmt_key == old; |
3b96766f JB |
205 | |
206 | if (defkey && !new) | |
207 | __ieee80211_set_default_key(sdata, -1); | |
3cfcf6ac JM |
208 | if (defmgmtkey && !new) |
209 | __ieee80211_set_default_mgmt_key(sdata, -1); | |
3b96766f JB |
210 | |
211 | rcu_assign_pointer(sdata->keys[idx], new); | |
212 | if (defkey && new) | |
213 | __ieee80211_set_default_key(sdata, new->conf.keyidx); | |
3cfcf6ac JM |
214 | if (defmgmtkey && new) |
215 | __ieee80211_set_default_mgmt_key(sdata, | |
216 | new->conf.keyidx); | |
3b96766f JB |
217 | } |
218 | ||
219 | if (old) { | |
220 | /* | |
221 | * We'll use an empty list to indicate that the key | |
222 | * has already been removed. | |
223 | */ | |
224 | list_del_init(&old->list); | |
225 | } | |
11a843b7 JB |
226 | } |
227 | ||
97359d12 | 228 | struct ieee80211_key *ieee80211_key_alloc(u32 cipher, int idx, size_t key_len, |
faa8fdc8 JM |
229 | const u8 *key_data, |
230 | size_t seq_len, const u8 *seq) | |
1f5a7e47 JB |
231 | { |
232 | struct ieee80211_key *key; | |
1ac62ba7 | 233 | int i, j, err; |
1f5a7e47 | 234 | |
3cfcf6ac | 235 | BUG_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS); |
11a843b7 JB |
236 | |
237 | key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL); | |
1f5a7e47 | 238 | if (!key) |
1ac62ba7 | 239 | return ERR_PTR(-ENOMEM); |
11a843b7 JB |
240 | |
241 | /* | |
242 | * Default to software encryption; we'll later upload the | |
243 | * key to the hardware if possible. | |
244 | */ | |
11a843b7 JB |
245 | key->conf.flags = 0; |
246 | key->flags = 0; | |
247 | ||
97359d12 | 248 | key->conf.cipher = cipher; |
11a843b7 JB |
249 | key->conf.keyidx = idx; |
250 | key->conf.keylen = key_len; | |
97359d12 JB |
251 | switch (cipher) { |
252 | case WLAN_CIPHER_SUITE_WEP40: | |
253 | case WLAN_CIPHER_SUITE_WEP104: | |
76708dee FF |
254 | key->conf.iv_len = WEP_IV_LEN; |
255 | key->conf.icv_len = WEP_ICV_LEN; | |
256 | break; | |
97359d12 | 257 | case WLAN_CIPHER_SUITE_TKIP: |
76708dee FF |
258 | key->conf.iv_len = TKIP_IV_LEN; |
259 | key->conf.icv_len = TKIP_ICV_LEN; | |
9f26a952 | 260 | if (seq) { |
faa8fdc8 JM |
261 | for (i = 0; i < NUM_RX_DATA_QUEUES; i++) { |
262 | key->u.tkip.rx[i].iv32 = | |
263 | get_unaligned_le32(&seq[2]); | |
264 | key->u.tkip.rx[i].iv16 = | |
265 | get_unaligned_le16(seq); | |
266 | } | |
267 | } | |
76708dee | 268 | break; |
97359d12 | 269 | case WLAN_CIPHER_SUITE_CCMP: |
76708dee FF |
270 | key->conf.iv_len = CCMP_HDR_LEN; |
271 | key->conf.icv_len = CCMP_MIC_LEN; | |
9f26a952 | 272 | if (seq) { |
9190252c | 273 | for (i = 0; i < NUM_RX_DATA_QUEUES + 1; i++) |
faa8fdc8 JM |
274 | for (j = 0; j < CCMP_PN_LEN; j++) |
275 | key->u.ccmp.rx_pn[i][j] = | |
276 | seq[CCMP_PN_LEN - j - 1]; | |
277 | } | |
11a843b7 JB |
278 | /* |
279 | * Initialize AES key state here as an optimization so that | |
280 | * it does not need to be initialized for every packet. | |
281 | */ | |
282 | key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(key_data); | |
1ac62ba7 BH |
283 | if (IS_ERR(key->u.ccmp.tfm)) { |
284 | err = PTR_ERR(key->u.ccmp.tfm); | |
3b96766f | 285 | kfree(key); |
1ac62ba7 | 286 | key = ERR_PTR(err); |
11a843b7 | 287 | } |
60ae0f20 JB |
288 | break; |
289 | case WLAN_CIPHER_SUITE_AES_CMAC: | |
290 | key->conf.iv_len = 0; | |
291 | key->conf.icv_len = sizeof(struct ieee80211_mmie); | |
292 | if (seq) | |
293 | for (j = 0; j < 6; j++) | |
294 | key->u.aes_cmac.rx_pn[j] = seq[6 - j - 1]; | |
3cfcf6ac JM |
295 | /* |
296 | * Initialize AES key state here as an optimization so that | |
297 | * it does not need to be initialized for every packet. | |
298 | */ | |
299 | key->u.aes_cmac.tfm = | |
300 | ieee80211_aes_cmac_key_setup(key_data); | |
1ac62ba7 BH |
301 | if (IS_ERR(key->u.aes_cmac.tfm)) { |
302 | err = PTR_ERR(key->u.aes_cmac.tfm); | |
3cfcf6ac | 303 | kfree(key); |
1ac62ba7 | 304 | key = ERR_PTR(err); |
3cfcf6ac | 305 | } |
60ae0f20 | 306 | break; |
3cfcf6ac | 307 | } |
60ae0f20 JB |
308 | memcpy(key->conf.key, key_data, key_len); |
309 | INIT_LIST_HEAD(&key->list); | |
3cfcf6ac | 310 | |
db4d1169 JB |
311 | return key; |
312 | } | |
11a843b7 | 313 | |
ad0e2b5a JB |
314 | static void __ieee80211_key_destroy(struct ieee80211_key *key) |
315 | { | |
316 | if (!key) | |
317 | return; | |
318 | ||
32162a4d JM |
319 | if (key->local) |
320 | ieee80211_key_disable_hw_accel(key); | |
ad0e2b5a | 321 | |
97359d12 | 322 | if (key->conf.cipher == WLAN_CIPHER_SUITE_CCMP) |
ad0e2b5a | 323 | ieee80211_aes_key_free(key->u.ccmp.tfm); |
97359d12 | 324 | if (key->conf.cipher == WLAN_CIPHER_SUITE_AES_CMAC) |
ad0e2b5a | 325 | ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm); |
32162a4d JM |
326 | if (key->local) |
327 | ieee80211_debugfs_key_remove(key); | |
ad0e2b5a JB |
328 | |
329 | kfree(key); | |
330 | } | |
331 | ||
db4d1169 JB |
332 | void ieee80211_key_link(struct ieee80211_key *key, |
333 | struct ieee80211_sub_if_data *sdata, | |
334 | struct sta_info *sta) | |
335 | { | |
336 | struct ieee80211_key *old_key; | |
337 | int idx; | |
338 | ||
db4d1169 JB |
339 | BUG_ON(!sdata); |
340 | BUG_ON(!key); | |
341 | ||
342 | idx = key->conf.keyidx; | |
343 | key->local = sdata->local; | |
344 | key->sdata = sdata; | |
345 | key->sta = sta; | |
346 | ||
11a843b7 | 347 | if (sta) { |
11a843b7 JB |
348 | /* |
349 | * some hardware cannot handle TKIP with QoS, so | |
350 | * we indicate whether QoS could be in use. | |
351 | */ | |
07346f81 | 352 | if (test_sta_flags(sta, WLAN_STA_WME)) |
11a843b7 | 353 | key->conf.flags |= IEEE80211_KEY_FLAG_WMM_STA; |
c6adbd21 ID |
354 | |
355 | /* | |
356 | * This key is for a specific sta interface, | |
357 | * inform the driver that it should try to store | |
358 | * this key as pairwise key. | |
359 | */ | |
360 | key->conf.flags |= IEEE80211_KEY_FLAG_PAIRWISE; | |
11a843b7 | 361 | } else { |
05c914fe | 362 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { |
11a843b7 JB |
363 | struct sta_info *ap; |
364 | ||
3b96766f JB |
365 | /* |
366 | * We're getting a sta pointer in, | |
367 | * so must be under RCU read lock. | |
368 | */ | |
d0709a65 | 369 | |
11a843b7 | 370 | /* same here, the AP could be using QoS */ |
abe60632 | 371 | ap = sta_info_get(key->sdata, key->sdata->u.mgd.bssid); |
11a843b7 | 372 | if (ap) { |
07346f81 | 373 | if (test_sta_flags(ap, WLAN_STA_WME)) |
11a843b7 JB |
374 | key->conf.flags |= |
375 | IEEE80211_KEY_FLAG_WMM_STA; | |
11a843b7 JB |
376 | } |
377 | } | |
11a843b7 JB |
378 | } |
379 | ||
ad0e2b5a | 380 | mutex_lock(&sdata->local->key_mtx); |
3b96766f | 381 | |
d4e46a3d | 382 | if (sta) |
db4d1169 | 383 | old_key = sta->key; |
d4e46a3d | 384 | else |
db4d1169 JB |
385 | old_key = sdata->keys[idx]; |
386 | ||
387 | __ieee80211_key_replace(sdata, sta, old_key, key); | |
ad0e2b5a | 388 | __ieee80211_key_destroy(old_key); |
d4e46a3d | 389 | |
ad0e2b5a | 390 | ieee80211_debugfs_key_add(key); |
db4d1169 | 391 | |
ad0e2b5a | 392 | ieee80211_key_enable_hw_accel(key); |
523d2f69 | 393 | |
ad0e2b5a | 394 | mutex_unlock(&sdata->local->key_mtx); |
1f5a7e47 JB |
395 | } |
396 | ||
3a245766 | 397 | static void __ieee80211_key_free(struct ieee80211_key *key) |
1f5a7e47 | 398 | { |
3b96766f JB |
399 | /* |
400 | * Replace key with nothingness if it was ever used. | |
401 | */ | |
3a245766 | 402 | if (key->sdata) |
3b96766f JB |
403 | __ieee80211_key_replace(key->sdata, key->sta, |
404 | key, NULL); | |
ad0e2b5a | 405 | __ieee80211_key_destroy(key); |
3b96766f | 406 | } |
d4e46a3d | 407 | |
32162a4d JM |
408 | void ieee80211_key_free(struct ieee80211_local *local, |
409 | struct ieee80211_key *key) | |
3b96766f | 410 | { |
3a245766 | 411 | if (!key) |
3b96766f JB |
412 | return; |
413 | ||
ad0e2b5a | 414 | mutex_lock(&local->key_mtx); |
3a245766 | 415 | __ieee80211_key_free(key); |
ad0e2b5a | 416 | mutex_unlock(&local->key_mtx); |
3a245766 JB |
417 | } |
418 | ||
ad0e2b5a | 419 | void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata) |
3a245766 JB |
420 | { |
421 | struct ieee80211_key *key; | |
11a843b7 | 422 | |
3a245766 | 423 | ASSERT_RTNL(); |
11a843b7 | 424 | |
9607e6b6 | 425 | if (WARN_ON(!ieee80211_sdata_running(sdata))) |
3a245766 | 426 | return; |
11a843b7 | 427 | |
ad0e2b5a | 428 | mutex_lock(&sdata->local->key_mtx); |
11a843b7 | 429 | |
ad0e2b5a JB |
430 | list_for_each_entry(key, &sdata->key_list, list) |
431 | ieee80211_key_enable_hw_accel(key); | |
3b96766f | 432 | |
ad0e2b5a | 433 | mutex_unlock(&sdata->local->key_mtx); |
11a843b7 JB |
434 | } |
435 | ||
ad0e2b5a | 436 | void ieee80211_disable_keys(struct ieee80211_sub_if_data *sdata) |
11a843b7 JB |
437 | { |
438 | struct ieee80211_key *key; | |
439 | ||
ad0e2b5a | 440 | ASSERT_RTNL(); |
db4d1169 | 441 | |
ad0e2b5a | 442 | mutex_lock(&sdata->local->key_mtx); |
11a843b7 | 443 | |
ad0e2b5a JB |
444 | list_for_each_entry(key, &sdata->key_list, list) |
445 | ieee80211_key_disable_hw_accel(key); | |
11a843b7 | 446 | |
ad0e2b5a | 447 | mutex_unlock(&sdata->local->key_mtx); |
3b96766f | 448 | } |
11a843b7 | 449 | |
3b96766f JB |
450 | void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata) |
451 | { | |
452 | struct ieee80211_key *key, *tmp; | |
db4d1169 | 453 | |
ad0e2b5a | 454 | mutex_lock(&sdata->local->key_mtx); |
3b96766f JB |
455 | |
456 | ieee80211_debugfs_key_remove_default(sdata); | |
3cfcf6ac | 457 | ieee80211_debugfs_key_remove_mgmt_default(sdata); |
3b96766f JB |
458 | |
459 | list_for_each_entry_safe(key, tmp, &sdata->key_list, list) | |
3a245766 | 460 | __ieee80211_key_free(key); |
3b96766f | 461 | |
ad0e2b5a | 462 | mutex_unlock(&sdata->local->key_mtx); |
11a843b7 | 463 | } |