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x86: kvm guest: pvclock vsyscall support
[linux-2.6.git] / net / mac80211 / ibss.c
blob5f3620f0bc0a651257aa53e28b91c4b2114be637
1 /*
2 * IBSS mode implementation
3 * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
4 * Copyright 2004, Instant802 Networks, Inc.
5 * Copyright 2005, Devicescape Software, Inc.
6 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
7 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
8 * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13 */
14
15 #include <linux/delay.h>
16 #include <linux/slab.h>
17 #include <linux/if_ether.h>
18 #include <linux/skbuff.h>
19 #include <linux/if_arp.h>
20 #include <linux/etherdevice.h>
21 #include <linux/rtnetlink.h>
22 #include <net/mac80211.h>
23
24 #include "ieee80211_i.h"
25 #include "driver-ops.h"
26 #include "rate.h"
27
28 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
29 #define IEEE80211_SCAN_INTERVAL_SLOW (15 * HZ)
30 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
31
32 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
33 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
34
35 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
36
37
38 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
39 const u8 *bssid, const int beacon_int,
40 struct ieee80211_channel *chan,
41 const u32 basic_rates,
42 const u16 capability, u64 tsf)
43 {
44 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
45 struct ieee80211_local *local = sdata->local;
46 int rates, i;
47 struct sk_buff *skb;
48 struct ieee80211_mgmt *mgmt;
49 u8 *pos;
50 struct ieee80211_supported_band *sband;
51 struct cfg80211_bss *bss;
52 u32 bss_change;
53 u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
54 enum nl80211_channel_type channel_type;
55
56 lockdep_assert_held(&ifibss->mtx);
57
58 /* Reset own TSF to allow time synchronization work. */
59 drv_reset_tsf(local, sdata);
60
61 skb = ifibss->skb;
62 RCU_INIT_POINTER(ifibss->presp, NULL);
63 synchronize_rcu();
64 skb->data = skb->head;
65 skb->len = 0;
66 skb_reset_tail_pointer(skb);
67 skb_reserve(skb, sdata->local->hw.extra_tx_headroom);
68
69 if (!ether_addr_equal(ifibss->bssid, bssid))
70 sta_info_flush(sdata->local, sdata);
71
72 /* if merging, indicate to driver that we leave the old IBSS */
73 if (sdata->vif.bss_conf.ibss_joined) {
74 sdata->vif.bss_conf.ibss_joined = false;
75 netif_carrier_off(sdata->dev);
76 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS);
77 }
78
79 memcpy(ifibss->bssid, bssid, ETH_ALEN);
80
81 sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
82
83 local->oper_channel = chan;
84 channel_type = ifibss->channel_type;
85 if (!cfg80211_can_beacon_sec_chan(local->hw.wiphy, chan, channel_type))
86 channel_type = NL80211_CHAN_HT20;
87 if (!ieee80211_set_channel_type(local, sdata, channel_type)) {
88 /* can only fail due to HT40+/- mismatch */
89 channel_type = NL80211_CHAN_HT20;
90 WARN_ON(!ieee80211_set_channel_type(local, sdata,
91 NL80211_CHAN_HT20));
92 }
93 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
94
95 sband = local->hw.wiphy->bands[chan->band];
96
97 /* build supported rates array */
98 pos = supp_rates;
99 for (i = 0; i < sband->n_bitrates; i++) {
100 int rate = sband->bitrates[i].bitrate;
101 u8 basic = 0;
102 if (basic_rates & BIT(i))
103 basic = 0x80;
104 *pos++ = basic | (u8) (rate / 5);
105 }
106
107 /* Build IBSS probe response */
108 mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
109 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
110 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
111 IEEE80211_STYPE_PROBE_RESP);
112 eth_broadcast_addr(mgmt->da);
113 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
114 memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
115 mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
116 mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
117 mgmt->u.beacon.capab_info = cpu_to_le16(capability);
118
119 pos = skb_put(skb, 2 + ifibss->ssid_len);
120 *pos++ = WLAN_EID_SSID;
121 *pos++ = ifibss->ssid_len;
122 memcpy(pos, ifibss->ssid, ifibss->ssid_len);
123
124 rates = sband->n_bitrates;
125 if (rates > 8)
126 rates = 8;
127 pos = skb_put(skb, 2 + rates);
128 *pos++ = WLAN_EID_SUPP_RATES;
129 *pos++ = rates;
130 memcpy(pos, supp_rates, rates);
131
132 if (sband->band == IEEE80211_BAND_2GHZ) {
133 pos = skb_put(skb, 2 + 1);
134 *pos++ = WLAN_EID_DS_PARAMS;
135 *pos++ = 1;
136 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
137 }
138
139 pos = skb_put(skb, 2 + 2);
140 *pos++ = WLAN_EID_IBSS_PARAMS;
141 *pos++ = 2;
142 /* FIX: set ATIM window based on scan results */
143 *pos++ = 0;
144 *pos++ = 0;
145
146 if (sband->n_bitrates > 8) {
147 rates = sband->n_bitrates - 8;
148 pos = skb_put(skb, 2 + rates);
149 *pos++ = WLAN_EID_EXT_SUPP_RATES;
150 *pos++ = rates;
151 memcpy(pos, &supp_rates[8], rates);
152 }
153
154 if (ifibss->ie_len)
155 memcpy(skb_put(skb, ifibss->ie_len),
156 ifibss->ie, ifibss->ie_len);
157
158 /* add HT capability and information IEs */
159 if (channel_type && sband->ht_cap.ht_supported) {
160 pos = skb_put(skb, 4 +
161 sizeof(struct ieee80211_ht_cap) +
162 sizeof(struct ieee80211_ht_operation));
163 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
164 sband->ht_cap.cap);
165 /*
166 * Note: According to 802.11n-2009 9.13.3.1, HT Protection
167 * field and RIFS Mode are reserved in IBSS mode, therefore
168 * keep them at 0
169 */
170 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
171 chan, channel_type, 0);
172 }
173
174 if (local->hw.queues >= IEEE80211_NUM_ACS) {
175 pos = skb_put(skb, 9);
176 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
177 *pos++ = 7; /* len */
178 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
179 *pos++ = 0x50;
180 *pos++ = 0xf2;
181 *pos++ = 2; /* WME */
182 *pos++ = 0; /* WME info */
183 *pos++ = 1; /* WME ver */
184 *pos++ = 0; /* U-APSD no in use */
185 }
186
187 rcu_assign_pointer(ifibss->presp, skb);
188
189 sdata->vif.bss_conf.beacon_int = beacon_int;
190 sdata->vif.bss_conf.basic_rates = basic_rates;
191 bss_change = BSS_CHANGED_BEACON_INT;
192 bss_change |= ieee80211_reset_erp_info(sdata);
193 bss_change |= BSS_CHANGED_BSSID;
194 bss_change |= BSS_CHANGED_BEACON;
195 bss_change |= BSS_CHANGED_BEACON_ENABLED;
196 bss_change |= BSS_CHANGED_BASIC_RATES;
197 bss_change |= BSS_CHANGED_HT;
198 bss_change |= BSS_CHANGED_IBSS;
199 sdata->vif.bss_conf.ibss_joined = true;
200 ieee80211_bss_info_change_notify(sdata, bss_change);
201
202 ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
203
204 ifibss->state = IEEE80211_IBSS_MLME_JOINED;
205 mod_timer(&ifibss->timer,
206 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
207
208 bss = cfg80211_inform_bss_frame(local->hw.wiphy, chan,
209 mgmt, skb->len, 0, GFP_KERNEL);
210 cfg80211_put_bss(bss);
211 netif_carrier_on(sdata->dev);
212 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
213 }
214
215 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
216 struct ieee80211_bss *bss)
217 {
218 struct cfg80211_bss *cbss =
219 container_of((void *)bss, struct cfg80211_bss, priv);
220 struct ieee80211_supported_band *sband;
221 u32 basic_rates;
222 int i, j;
223 u16 beacon_int = cbss->beacon_interval;
224
225 lockdep_assert_held(&sdata->u.ibss.mtx);
226
227 if (beacon_int < 10)
228 beacon_int = 10;
229
230 sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
231
232 basic_rates = 0;
233
234 for (i = 0; i < bss->supp_rates_len; i++) {
235 int rate = (bss->supp_rates[i] & 0x7f) * 5;
236 bool is_basic = !!(bss->supp_rates[i] & 0x80);
237
238 for (j = 0; j < sband->n_bitrates; j++) {
239 if (sband->bitrates[j].bitrate == rate) {
240 if (is_basic)
241 basic_rates |= BIT(j);
242 break;
243 }
244 }
245 }
246
247 __ieee80211_sta_join_ibss(sdata, cbss->bssid,
248 beacon_int,
249 cbss->channel,
250 basic_rates,
251 cbss->capability,
252 cbss->tsf);
253 }
254
255 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta,
256 bool auth)
257 __acquires(RCU)
258 {
259 struct ieee80211_sub_if_data *sdata = sta->sdata;
260 u8 addr[ETH_ALEN];
261
262 memcpy(addr, sta->sta.addr, ETH_ALEN);
263
264 ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
265
266 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
267 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
268 /* authorize the station only if the network is not RSN protected. If
269 * not wait for the userspace to authorize it */
270 if (!sta->sdata->u.ibss.control_port)
271 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
272
273 rate_control_rate_init(sta);
274
275 /* If it fails, maybe we raced another insertion? */
276 if (sta_info_insert_rcu(sta))
277 return sta_info_get(sdata, addr);
278 if (auth && !sdata->u.ibss.auth_frame_registrations) {
279 ibss_dbg(sdata,
280 "TX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=1)\n",
281 sdata->vif.addr, addr, sdata->u.ibss.bssid);
282 ieee80211_send_auth(sdata, 1, WLAN_AUTH_OPEN, NULL, 0,
283 addr, sdata->u.ibss.bssid, NULL, 0, 0);
284 }
285 return sta;
286 }
287
288 static struct sta_info *
289 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
290 const u8 *bssid, const u8 *addr,
291 u32 supp_rates, bool auth)
292 __acquires(RCU)
293 {
294 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
295 struct ieee80211_local *local = sdata->local;
296 struct sta_info *sta;
297 int band = local->oper_channel->band;
298
299 /*
300 * XXX: Consider removing the least recently used entry and
301 * allow new one to be added.
302 */
303 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
304 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
305 sdata->name, addr);
306 rcu_read_lock();
307 return NULL;
308 }
309
310 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
311 rcu_read_lock();
312 return NULL;
313 }
314
315 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
316 rcu_read_lock();
317 return NULL;
318 }
319
320 sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
321 if (!sta) {
322 rcu_read_lock();
323 return NULL;
324 }
325
326 sta->last_rx = jiffies;
327
328 /* make sure mandatory rates are always added */
329 sta->sta.supp_rates[band] = supp_rates |
330 ieee80211_mandatory_rates(local, band);
331
332 return ieee80211_ibss_finish_sta(sta, auth);
333 }
334
335 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
336 struct ieee80211_mgmt *mgmt,
337 size_t len)
338 {
339 u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
340
341 if (len < IEEE80211_DEAUTH_FRAME_LEN)
342 return;
343
344 ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
345 mgmt->sa, mgmt->da, mgmt->bssid, reason);
346 sta_info_destroy_addr(sdata, mgmt->sa);
347 }
348
349 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
350 struct ieee80211_mgmt *mgmt,
351 size_t len)
352 {
353 u16 auth_alg, auth_transaction;
354 struct sta_info *sta;
355 u8 deauth_frame_buf[IEEE80211_DEAUTH_FRAME_LEN];
356
357 lockdep_assert_held(&sdata->u.ibss.mtx);
358
359 if (len < 24 + 6)
360 return;
361
362 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
363 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
364
365 if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
366 return;
367 ibss_dbg(sdata,
368 "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
369 mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
370 sta_info_destroy_addr(sdata, mgmt->sa);
371 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false);
372 rcu_read_unlock();
373
374 /*
375 * if we have any problem in allocating the new station, we reply with a
376 * DEAUTH frame to tell the other end that we had a problem
377 */
378 if (!sta) {
379 ieee80211_send_deauth_disassoc(sdata, sdata->u.ibss.bssid,
380 IEEE80211_STYPE_DEAUTH,
381 WLAN_REASON_UNSPECIFIED, true,
382 deauth_frame_buf);
383 return;
384 }
385
386 /*
387 * IEEE 802.11 standard does not require authentication in IBSS
388 * networks and most implementations do not seem to use it.
389 * However, try to reply to authentication attempts if someone
390 * has actually implemented this.
391 */
392 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0,
393 mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0);
394 }
395
396 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
397 struct ieee80211_mgmt *mgmt,
398 size_t len,
399 struct ieee80211_rx_status *rx_status,
400 struct ieee802_11_elems *elems,
401 bool beacon)
402 {
403 struct ieee80211_local *local = sdata->local;
404 int freq;
405 struct cfg80211_bss *cbss;
406 struct ieee80211_bss *bss;
407 struct sta_info *sta;
408 struct ieee80211_channel *channel;
409 u64 beacon_timestamp, rx_timestamp;
410 u32 supp_rates = 0;
411 enum ieee80211_band band = rx_status->band;
412 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
413 bool rates_updated = false;
414
415 if (elems->ds_params && elems->ds_params_len == 1)
416 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
417 band);
418 else
419 freq = rx_status->freq;
420
421 channel = ieee80211_get_channel(local->hw.wiphy, freq);
422
423 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
424 return;
425
426 if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
427 ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
428
429 rcu_read_lock();
430 sta = sta_info_get(sdata, mgmt->sa);
431
432 if (elems->supp_rates) {
433 supp_rates = ieee80211_sta_get_rates(local, elems,
434 band, NULL);
435 if (sta) {
436 u32 prev_rates;
437
438 prev_rates = sta->sta.supp_rates[band];
439 /* make sure mandatory rates are always added */
440 sta->sta.supp_rates[band] = supp_rates |
441 ieee80211_mandatory_rates(local, band);
442
443 if (sta->sta.supp_rates[band] != prev_rates) {
444 ibss_dbg(sdata,
445 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
446 sta->sta.addr, prev_rates,
447 sta->sta.supp_rates[band]);
448 rates_updated = true;
449 }
450 } else {
451 rcu_read_unlock();
452 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
453 mgmt->sa, supp_rates, true);
454 }
455 }
456
457 if (sta && elems->wmm_info)
458 set_sta_flag(sta, WLAN_STA_WME);
459
460 if (sta && elems->ht_operation && elems->ht_cap_elem &&
461 sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
462 /* we both use HT */
463 struct ieee80211_sta_ht_cap sta_ht_cap_new;
464 enum nl80211_channel_type channel_type =
465 ieee80211_ht_oper_to_channel_type(
466 elems->ht_operation);
467
468 ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
469 elems->ht_cap_elem,
470 &sta_ht_cap_new);
471
472 /*
473 * fall back to HT20 if we don't use or use
474 * the other extension channel
475 */
476 if (!(channel_type == NL80211_CHAN_HT40MINUS ||
477 channel_type == NL80211_CHAN_HT40PLUS) ||
478 channel_type != sdata->u.ibss.channel_type)
479 sta_ht_cap_new.cap &=
480 ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
481
482 if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new,
483 sizeof(sta_ht_cap_new))) {
484 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new,
485 sizeof(sta_ht_cap_new));
486 rates_updated = true;
487 }
488 }
489
490 if (sta && rates_updated) {
491 drv_sta_rc_update(local, sdata, &sta->sta,
492 IEEE80211_RC_SUPP_RATES_CHANGED);
493 rate_control_rate_init(sta);
494 }
495
496 rcu_read_unlock();
497 }
498
499 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
500 channel, beacon);
501 if (!bss)
502 return;
503
504 cbss = container_of((void *)bss, struct cfg80211_bss, priv);
505
506 /* was just updated in ieee80211_bss_info_update */
507 beacon_timestamp = cbss->tsf;
508
509 /* check if we need to merge IBSS */
510
511 /* we use a fixed BSSID */
512 if (sdata->u.ibss.fixed_bssid)
513 goto put_bss;
514
515 /* not an IBSS */
516 if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
517 goto put_bss;
518
519 /* different channel */
520 if (cbss->channel != local->oper_channel)
521 goto put_bss;
522
523 /* different SSID */
524 if (elems->ssid_len != sdata->u.ibss.ssid_len ||
525 memcmp(elems->ssid, sdata->u.ibss.ssid,
526 sdata->u.ibss.ssid_len))
527 goto put_bss;
528
529 /* same BSSID */
530 if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
531 goto put_bss;
532
533 if (rx_status->flag & RX_FLAG_MACTIME_MPDU) {
534 /*
535 * For correct IBSS merging we need mactime; since mactime is
536 * defined as the time the first data symbol of the frame hits
537 * the PHY, and the timestamp of the beacon is defined as "the
538 * time that the data symbol containing the first bit of the
539 * timestamp is transmitted to the PHY plus the transmitting
540 * STA's delays through its local PHY from the MAC-PHY
541 * interface to its interface with the WM" (802.11 11.1.2)
542 * - equals the time this bit arrives at the receiver - we have
543 * to take into account the offset between the two.
544 *
545 * E.g. at 1 MBit that means mactime is 192 usec earlier
546 * (=24 bytes * 8 usecs/byte) than the beacon timestamp.
547 */
548 int rate;
549
550 if (rx_status->flag & RX_FLAG_HT)
551 rate = 65; /* TODO: HT rates */
552 else
553 rate = local->hw.wiphy->bands[band]->
554 bitrates[rx_status->rate_idx].bitrate;
555
556 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate);
557 } else {
558 /*
559 * second best option: get current TSF
560 * (will return -1 if not supported)
561 */
562 rx_timestamp = drv_get_tsf(local, sdata);
563 }
564
565 ibss_dbg(sdata,
566 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
567 mgmt->sa, mgmt->bssid,
568 (unsigned long long)rx_timestamp,
569 (unsigned long long)beacon_timestamp,
570 (unsigned long long)(rx_timestamp - beacon_timestamp),
571 jiffies);
572
573 if (beacon_timestamp > rx_timestamp) {
574 ibss_dbg(sdata,
575 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
576 mgmt->bssid);
577 ieee80211_sta_join_ibss(sdata, bss);
578 supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL);
579 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
580 supp_rates, true);
581 rcu_read_unlock();
582 }
583
584 put_bss:
585 ieee80211_rx_bss_put(local, bss);
586 }
587
588 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
589 const u8 *bssid, const u8 *addr,
590 u32 supp_rates)
591 {
592 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
593 struct ieee80211_local *local = sdata->local;
594 struct sta_info *sta;
595 int band = local->oper_channel->band;
596
597 /*
598 * XXX: Consider removing the least recently used entry and
599 * allow new one to be added.
600 */
601 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
602 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
603 sdata->name, addr);
604 return;
605 }
606
607 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
608 return;
609
610 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
611 return;
612
613 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
614 if (!sta)
615 return;
616
617 sta->last_rx = jiffies;
618
619 /* make sure mandatory rates are always added */
620 sta->sta.supp_rates[band] = supp_rates |
621 ieee80211_mandatory_rates(local, band);
622
623 spin_lock(&ifibss->incomplete_lock);
624 list_add(&sta->list, &ifibss->incomplete_stations);
625 spin_unlock(&ifibss->incomplete_lock);
626 ieee80211_queue_work(&local->hw, &sdata->work);
627 }
628
629 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
630 {
631 struct ieee80211_local *local = sdata->local;
632 int active = 0;
633 struct sta_info *sta;
634
635 lockdep_assert_held(&sdata->u.ibss.mtx);
636
637 rcu_read_lock();
638
639 list_for_each_entry_rcu(sta, &local->sta_list, list) {
640 if (sta->sdata == sdata &&
641 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
642 jiffies)) {
643 active++;
644 break;
645 }
646 }
647
648 rcu_read_unlock();
649
650 return active;
651 }
652
653 /*
654 * This function is called with state == IEEE80211_IBSS_MLME_JOINED
655 */
656
657 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
658 {
659 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
660
661 lockdep_assert_held(&ifibss->mtx);
662
663 mod_timer(&ifibss->timer,
664 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
665
666 ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
667
668 if (time_before(jiffies, ifibss->last_scan_completed +
669 IEEE80211_IBSS_MERGE_INTERVAL))
670 return;
671
672 if (ieee80211_sta_active_ibss(sdata))
673 return;
674
675 if (ifibss->fixed_channel)
676 return;
677
678 sdata_info(sdata,
679 "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
680
681 ieee80211_request_internal_scan(sdata,
682 ifibss->ssid, ifibss->ssid_len, NULL);
683 }
684
685 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
686 {
687 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
688 u8 bssid[ETH_ALEN];
689 u16 capability;
690 int i;
691
692 lockdep_assert_held(&ifibss->mtx);
693
694 if (ifibss->fixed_bssid) {
695 memcpy(bssid, ifibss->bssid, ETH_ALEN);
696 } else {
697 /* Generate random, not broadcast, locally administered BSSID. Mix in
698 * own MAC address to make sure that devices that do not have proper
699 * random number generator get different BSSID. */
700 get_random_bytes(bssid, ETH_ALEN);
701 for (i = 0; i < ETH_ALEN; i++)
702 bssid[i] ^= sdata->vif.addr[i];
703 bssid[0] &= ~0x01;
704 bssid[0] |= 0x02;
705 }
706
707 sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
708
709 capability = WLAN_CAPABILITY_IBSS;
710
711 if (ifibss->privacy)
712 capability |= WLAN_CAPABILITY_PRIVACY;
713 else
714 sdata->drop_unencrypted = 0;
715
716 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
717 ifibss->channel, ifibss->basic_rates,
718 capability, 0);
719 }
720
721 /*
722 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
723 */
724
725 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
726 {
727 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
728 struct ieee80211_local *local = sdata->local;
729 struct cfg80211_bss *cbss;
730 struct ieee80211_channel *chan = NULL;
731 const u8 *bssid = NULL;
732 int active_ibss;
733 u16 capability;
734
735 lockdep_assert_held(&ifibss->mtx);
736
737 active_ibss = ieee80211_sta_active_ibss(sdata);
738 ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
739
740 if (active_ibss)
741 return;
742
743 capability = WLAN_CAPABILITY_IBSS;
744 if (ifibss->privacy)
745 capability |= WLAN_CAPABILITY_PRIVACY;
746 if (ifibss->fixed_bssid)
747 bssid = ifibss->bssid;
748 if (ifibss->fixed_channel)
749 chan = ifibss->channel;
750 if (!is_zero_ether_addr(ifibss->bssid))
751 bssid = ifibss->bssid;
752 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
753 ifibss->ssid, ifibss->ssid_len,
754 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
755 capability);
756
757 if (cbss) {
758 struct ieee80211_bss *bss;
759
760 bss = (void *)cbss->priv;
761 ibss_dbg(sdata,
762 "sta_find_ibss: selected %pM current %pM\n",
763 cbss->bssid, ifibss->bssid);
764 sdata_info(sdata,
765 "Selected IBSS BSSID %pM based on configured SSID\n",
766 cbss->bssid);
767
768 ieee80211_sta_join_ibss(sdata, bss);
769 ieee80211_rx_bss_put(local, bss);
770 return;
771 }
772
773 ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
774
775 /* Selected IBSS not found in current scan results - try to scan */
776 if (time_after(jiffies, ifibss->last_scan_completed +
777 IEEE80211_SCAN_INTERVAL)) {
778 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
779
780 ieee80211_request_internal_scan(sdata,
781 ifibss->ssid, ifibss->ssid_len,
782 ifibss->fixed_channel ? ifibss->channel : NULL);
783 } else {
784 int interval = IEEE80211_SCAN_INTERVAL;
785
786 if (time_after(jiffies, ifibss->ibss_join_req +
787 IEEE80211_IBSS_JOIN_TIMEOUT)) {
788 if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) {
789 ieee80211_sta_create_ibss(sdata);
790 return;
791 }
792 sdata_info(sdata, "IBSS not allowed on %d MHz\n",
793 local->oper_channel->center_freq);
794
795 /* No IBSS found - decrease scan interval and continue
796 * scanning. */
797 interval = IEEE80211_SCAN_INTERVAL_SLOW;
798 }
799
800 mod_timer(&ifibss->timer,
801 round_jiffies(jiffies + interval));
802 }
803 }
804
805 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
806 struct sk_buff *req)
807 {
808 struct ieee80211_mgmt *mgmt = (void *)req->data;
809 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
810 struct ieee80211_local *local = sdata->local;
811 int tx_last_beacon, len = req->len;
812 struct sk_buff *skb;
813 struct ieee80211_mgmt *resp;
814 struct sk_buff *presp;
815 u8 *pos, *end;
816
817 lockdep_assert_held(&ifibss->mtx);
818
819 presp = rcu_dereference_protected(ifibss->presp,
820 lockdep_is_held(&ifibss->mtx));
821
822 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
823 len < 24 + 2 || !presp)
824 return;
825
826 tx_last_beacon = drv_tx_last_beacon(local);
827
828 ibss_dbg(sdata,
829 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
830 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
831
832 if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
833 return;
834
835 if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
836 !is_broadcast_ether_addr(mgmt->bssid))
837 return;
838
839 end = ((u8 *) mgmt) + len;
840 pos = mgmt->u.probe_req.variable;
841 if (pos[0] != WLAN_EID_SSID ||
842 pos + 2 + pos[1] > end) {
843 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
844 mgmt->sa);
845 return;
846 }
847 if (pos[1] != 0 &&
848 (pos[1] != ifibss->ssid_len ||
849 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
850 /* Ignore ProbeReq for foreign SSID */
851 return;
852 }
853
854 /* Reply with ProbeResp */
855 skb = skb_copy(presp, GFP_KERNEL);
856 if (!skb)
857 return;
858
859 resp = (struct ieee80211_mgmt *) skb->data;
860 memcpy(resp->da, mgmt->sa, ETH_ALEN);
861 ibss_dbg(sdata, "Sending ProbeResp to %pM\n", resp->da);
862 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
863 ieee80211_tx_skb(sdata, skb);
864 }
865
866 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
867 struct ieee80211_mgmt *mgmt,
868 size_t len,
869 struct ieee80211_rx_status *rx_status)
870 {
871 size_t baselen;
872 struct ieee802_11_elems elems;
873
874 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
875 if (baselen > len)
876 return;
877
878 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
879 &elems);
880
881 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
882 }
883
884 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
885 struct ieee80211_mgmt *mgmt,
886 size_t len,
887 struct ieee80211_rx_status *rx_status)
888 {
889 size_t baselen;
890 struct ieee802_11_elems elems;
891
892 /* Process beacon from the current BSS */
893 baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
894 if (baselen > len)
895 return;
896
897 ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
898
899 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
900 }
901
902 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
903 struct sk_buff *skb)
904 {
905 struct ieee80211_rx_status *rx_status;
906 struct ieee80211_mgmt *mgmt;
907 u16 fc;
908
909 rx_status = IEEE80211_SKB_RXCB(skb);
910 mgmt = (struct ieee80211_mgmt *) skb->data;
911 fc = le16_to_cpu(mgmt->frame_control);
912
913 mutex_lock(&sdata->u.ibss.mtx);
914
915 if (!sdata->u.ibss.ssid_len)
916 goto mgmt_out; /* not ready to merge yet */
917
918 switch (fc & IEEE80211_FCTL_STYPE) {
919 case IEEE80211_STYPE_PROBE_REQ:
920 ieee80211_rx_mgmt_probe_req(sdata, skb);
921 break;
922 case IEEE80211_STYPE_PROBE_RESP:
923 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
924 rx_status);
925 break;
926 case IEEE80211_STYPE_BEACON:
927 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
928 rx_status);
929 break;
930 case IEEE80211_STYPE_AUTH:
931 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
932 break;
933 case IEEE80211_STYPE_DEAUTH:
934 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
935 break;
936 }
937
938 mgmt_out:
939 mutex_unlock(&sdata->u.ibss.mtx);
940 }
941
942 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
943 {
944 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
945 struct sta_info *sta;
946
947 mutex_lock(&ifibss->mtx);
948
949 /*
950 * Work could be scheduled after scan or similar
951 * when we aren't even joined (or trying) with a
952 * network.
953 */
954 if (!ifibss->ssid_len)
955 goto out;
956
957 spin_lock_bh(&ifibss->incomplete_lock);
958 while (!list_empty(&ifibss->incomplete_stations)) {
959 sta = list_first_entry(&ifibss->incomplete_stations,
960 struct sta_info, list);
961 list_del(&sta->list);
962 spin_unlock_bh(&ifibss->incomplete_lock);
963
964 ieee80211_ibss_finish_sta(sta, true);
965 rcu_read_unlock();
966 spin_lock_bh(&ifibss->incomplete_lock);
967 }
968 spin_unlock_bh(&ifibss->incomplete_lock);
969
970 switch (ifibss->state) {
971 case IEEE80211_IBSS_MLME_SEARCH:
972 ieee80211_sta_find_ibss(sdata);
973 break;
974 case IEEE80211_IBSS_MLME_JOINED:
975 ieee80211_sta_merge_ibss(sdata);
976 break;
977 default:
978 WARN_ON(1);
979 break;
980 }
981
982 out:
983 mutex_unlock(&ifibss->mtx);
984 }
985
986 static void ieee80211_ibss_timer(unsigned long data)
987 {
988 struct ieee80211_sub_if_data *sdata =
989 (struct ieee80211_sub_if_data *) data;
990 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
991 struct ieee80211_local *local = sdata->local;
992
993 if (local->quiescing) {
994 ifibss->timer_running = true;
995 return;
996 }
997
998 ieee80211_queue_work(&local->hw, &sdata->work);
999 }
1000
1001 #ifdef CONFIG_PM
1002 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
1003 {
1004 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1005
1006 if (del_timer_sync(&ifibss->timer))
1007 ifibss->timer_running = true;
1008 }
1009
1010 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
1011 {
1012 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1013
1014 if (ifibss->timer_running) {
1015 add_timer(&ifibss->timer);
1016 ifibss->timer_running = false;
1017 }
1018 }
1019 #endif
1020
1021 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1022 {
1023 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1024
1025 setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1026 (unsigned long) sdata);
1027 mutex_init(&ifibss->mtx);
1028 INIT_LIST_HEAD(&ifibss->incomplete_stations);
1029 spin_lock_init(&ifibss->incomplete_lock);
1030 }
1031
1032 /* scan finished notification */
1033 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1034 {
1035 struct ieee80211_sub_if_data *sdata;
1036
1037 mutex_lock(&local->iflist_mtx);
1038 list_for_each_entry(sdata, &local->interfaces, list) {
1039 if (!ieee80211_sdata_running(sdata))
1040 continue;
1041 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1042 continue;
1043 sdata->u.ibss.last_scan_completed = jiffies;
1044 ieee80211_queue_work(&local->hw, &sdata->work);
1045 }
1046 mutex_unlock(&local->iflist_mtx);
1047 }
1048
1049 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1050 struct cfg80211_ibss_params *params)
1051 {
1052 struct sk_buff *skb;
1053 u32 changed = 0;
1054
1055 skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1056 sizeof(struct ieee80211_hdr_3addr) +
1057 12 /* struct ieee80211_mgmt.u.beacon */ +
1058 2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1059 2 + 8 /* max Supported Rates */ +
1060 3 /* max DS params */ +
1061 4 /* IBSS params */ +
1062 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1063 2 + sizeof(struct ieee80211_ht_cap) +
1064 2 + sizeof(struct ieee80211_ht_operation) +
1065 params->ie_len);
1066 if (!skb)
1067 return -ENOMEM;
1068
1069 mutex_lock(&sdata->u.ibss.mtx);
1070
1071 if (params->bssid) {
1072 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1073 sdata->u.ibss.fixed_bssid = true;
1074 } else
1075 sdata->u.ibss.fixed_bssid = false;
1076
1077 sdata->u.ibss.privacy = params->privacy;
1078 sdata->u.ibss.control_port = params->control_port;
1079 sdata->u.ibss.basic_rates = params->basic_rates;
1080 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1081 sizeof(params->mcast_rate));
1082
1083 sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1084
1085 sdata->u.ibss.channel = params->channel;
1086 sdata->u.ibss.channel_type = params->channel_type;
1087 sdata->u.ibss.fixed_channel = params->channel_fixed;
1088
1089 /* fix ourselves to that channel now already */
1090 if (params->channel_fixed) {
1091 sdata->local->oper_channel = params->channel;
1092 if (!ieee80211_set_channel_type(sdata->local, sdata,
1093 params->channel_type)) {
1094 mutex_unlock(&sdata->u.ibss.mtx);
1095 kfree_skb(skb);
1096 return -EINVAL;
1097 }
1098 }
1099
1100 if (params->ie) {
1101 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1102 GFP_KERNEL);
1103 if (sdata->u.ibss.ie)
1104 sdata->u.ibss.ie_len = params->ie_len;
1105 }
1106
1107 sdata->u.ibss.skb = skb;
1108 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1109 sdata->u.ibss.ibss_join_req = jiffies;
1110
1111 memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN);
1112 sdata->u.ibss.ssid_len = params->ssid_len;
1113
1114 mutex_unlock(&sdata->u.ibss.mtx);
1115
1116 mutex_lock(&sdata->local->mtx);
1117 ieee80211_recalc_idle(sdata->local);
1118 mutex_unlock(&sdata->local->mtx);
1119
1120 /*
1121 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1122 * reserved, but an HT STA shall protect HT transmissions as though
1123 * the HT Protection field were set to non-HT mixed mode.
1124 *
1125 * In an IBSS, the RIFS Mode field of the HT Operation element is
1126 * also reserved, but an HT STA shall operate as though this field
1127 * were set to 1.
1128 */
1129
1130 sdata->vif.bss_conf.ht_operation_mode |=
1131 IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1132 | IEEE80211_HT_PARAM_RIFS_MODE;
1133
1134 changed |= BSS_CHANGED_HT;
1135 ieee80211_bss_info_change_notify(sdata, changed);
1136
1137 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1138
1139 return 0;
1140 }
1141
1142 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1143 {
1144 struct sk_buff *skb;
1145 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1146 struct ieee80211_local *local = sdata->local;
1147 struct cfg80211_bss *cbss;
1148 u16 capability;
1149 int active_ibss;
1150 struct sta_info *sta;
1151
1152 mutex_lock(&sdata->u.ibss.mtx);
1153
1154 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1155 memset(sdata->u.ibss.bssid, 0, ETH_ALEN);
1156 sdata->u.ibss.ssid_len = 0;
1157
1158 active_ibss = ieee80211_sta_active_ibss(sdata);
1159
1160 if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1161 capability = WLAN_CAPABILITY_IBSS;
1162
1163 if (ifibss->privacy)
1164 capability |= WLAN_CAPABILITY_PRIVACY;
1165
1166 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel,
1167 ifibss->bssid, ifibss->ssid,
1168 ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1169 WLAN_CAPABILITY_PRIVACY,
1170 capability);
1171
1172 if (cbss) {
1173 cfg80211_unlink_bss(local->hw.wiphy, cbss);
1174 cfg80211_put_bss(cbss);
1175 }
1176 }
1177
1178 sta_info_flush(sdata->local, sdata);
1179
1180 spin_lock_bh(&ifibss->incomplete_lock);
1181 while (!list_empty(&ifibss->incomplete_stations)) {
1182 sta = list_first_entry(&ifibss->incomplete_stations,
1183 struct sta_info, list);
1184 list_del(&sta->list);
1185 spin_unlock_bh(&ifibss->incomplete_lock);
1186
1187 sta_info_free(local, sta);
1188 spin_lock_bh(&ifibss->incomplete_lock);
1189 }
1190 spin_unlock_bh(&ifibss->incomplete_lock);
1191
1192 netif_carrier_off(sdata->dev);
1193
1194 /* remove beacon */
1195 kfree(sdata->u.ibss.ie);
1196 skb = rcu_dereference_protected(sdata->u.ibss.presp,
1197 lockdep_is_held(&sdata->u.ibss.mtx));
1198 RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1199 sdata->vif.bss_conf.ibss_joined = false;
1200 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1201 BSS_CHANGED_IBSS);
1202 synchronize_rcu();
1203 kfree_skb(skb);
1204
1205 skb_queue_purge(&sdata->skb_queue);
1206
1207 del_timer_sync(&sdata->u.ibss.timer);
1208
1209 mutex_unlock(&sdata->u.ibss.mtx);
1210
1211 mutex_lock(&local->mtx);
1212 ieee80211_recalc_idle(sdata->local);
1213 mutex_unlock(&local->mtx);
1214
1215 return 0;
1216 }
Linus' kernel tree