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
__ieee80211_sta_join_ibss(struct ieee80211_sub_if_data * sdata,const u8 * bssid,const int beacon_int,struct ieee80211_channel * chan,const u32 basic_rates,const u16 capability,u64 tsf)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 (compare_ether_addr(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 (channel_type > NL80211_CHAN_HT20 &&
86 !cfg80211_can_beacon_sec_chan(local->hw.wiphy, chan, channel_type))
87 channel_type = NL80211_CHAN_HT20;
88 if (!ieee80211_set_channel_type(local, sdata, channel_type)) {
89 /* can only fail due to HT40+/- mismatch */
90 channel_type = NL80211_CHAN_HT20;
91 WARN_ON(!ieee80211_set_channel_type(local, sdata,
92 NL80211_CHAN_HT20));
93 }
94 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
95
96 sband = local->hw.wiphy->bands[chan->band];
97
98 /* build supported rates array */
99 pos = supp_rates;
100 for (i = 0; i < sband->n_bitrates; i++) {
101 int rate = sband->bitrates[i].bitrate;
102 u8 basic = 0;
103 if (basic_rates & BIT(i))
104 basic = 0x80;
105 *pos++ = basic | (u8) (rate / 5);
106 }
107
108 /* Build IBSS probe response */
109 mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
110 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
111 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
112 IEEE80211_STYPE_PROBE_RESP);
113 memset(mgmt->da, 0xff, ETH_ALEN);
114 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
115 memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
116 mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
117 mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
118 mgmt->u.beacon.capab_info = cpu_to_le16(capability);
119
120 pos = skb_put(skb, 2 + ifibss->ssid_len);
121 *pos++ = WLAN_EID_SSID;
122 *pos++ = ifibss->ssid_len;
123 memcpy(pos, ifibss->ssid, ifibss->ssid_len);
124
125 rates = sband->n_bitrates;
126 if (rates > 8)
127 rates = 8;
128 pos = skb_put(skb, 2 + rates);
129 *pos++ = WLAN_EID_SUPP_RATES;
130 *pos++ = rates;
131 memcpy(pos, supp_rates, rates);
132
133 if (sband->band == IEEE80211_BAND_2GHZ) {
134 pos = skb_put(skb, 2 + 1);
135 *pos++ = WLAN_EID_DS_PARAMS;
136 *pos++ = 1;
137 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
138 }
139
140 pos = skb_put(skb, 2 + 2);
141 *pos++ = WLAN_EID_IBSS_PARAMS;
142 *pos++ = 2;
143 /* FIX: set ATIM window based on scan results */
144 *pos++ = 0;
145 *pos++ = 0;
146
147 if (sband->n_bitrates > 8) {
148 rates = sband->n_bitrates - 8;
149 pos = skb_put(skb, 2 + rates);
150 *pos++ = WLAN_EID_EXT_SUPP_RATES;
151 *pos++ = rates;
152 memcpy(pos, &supp_rates[8], rates);
153 }
154
155 if (ifibss->ie_len)
156 memcpy(skb_put(skb, ifibss->ie_len),
157 ifibss->ie, ifibss->ie_len);
158
159 /* add HT capability and information IEs */
160 if (channel_type && sband->ht_cap.ht_supported) {
161 pos = skb_put(skb, 4 +
162 sizeof(struct ieee80211_ht_cap) +
163 sizeof(struct ieee80211_ht_info));
164 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
165 sband->ht_cap.cap);
166 pos = ieee80211_ie_build_ht_info(pos,
167 &sband->ht_cap,
168 chan,
169 channel_type);
170 }
171
172 if (local->hw.queues >= 4) {
173 pos = skb_put(skb, 9);
174 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
175 *pos++ = 7; /* len */
176 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
177 *pos++ = 0x50;
178 *pos++ = 0xf2;
179 *pos++ = 2; /* WME */
180 *pos++ = 0; /* WME info */
181 *pos++ = 1; /* WME ver */
182 *pos++ = 0; /* U-APSD no in use */
183 }
184
185 rcu_assign_pointer(ifibss->presp, skb);
186
187 sdata->vif.bss_conf.beacon_int = beacon_int;
188 sdata->vif.bss_conf.basic_rates = basic_rates;
189 bss_change = BSS_CHANGED_BEACON_INT;
190 bss_change |= ieee80211_reset_erp_info(sdata);
191 bss_change |= BSS_CHANGED_BSSID;
192 bss_change |= BSS_CHANGED_BEACON;
193 bss_change |= BSS_CHANGED_BEACON_ENABLED;
194 bss_change |= BSS_CHANGED_BASIC_RATES;
195 bss_change |= BSS_CHANGED_HT;
196 bss_change |= BSS_CHANGED_IBSS;
197 sdata->vif.bss_conf.ibss_joined = true;
198 ieee80211_bss_info_change_notify(sdata, bss_change);
199
200 ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
201
202 ifibss->state = IEEE80211_IBSS_MLME_JOINED;
203 mod_timer(&ifibss->timer,
204 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
205
206 bss = cfg80211_inform_bss_frame(local->hw.wiphy, local->hw.conf.channel,
207 mgmt, skb->len, 0, GFP_KERNEL);
208 cfg80211_put_bss(bss);
209 netif_carrier_on(sdata->dev);
210 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
211 }
212
ieee80211_sta_join_ibss(struct ieee80211_sub_if_data * sdata,struct ieee80211_bss * bss)213 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
214 struct ieee80211_bss *bss)
215 {
216 struct cfg80211_bss *cbss =
217 container_of((void *)bss, struct cfg80211_bss, priv);
218 struct ieee80211_supported_band *sband;
219 u32 basic_rates;
220 int i, j;
221 u16 beacon_int = cbss->beacon_interval;
222
223 lockdep_assert_held(&sdata->u.ibss.mtx);
224
225 if (beacon_int < 10)
226 beacon_int = 10;
227
228 sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
229
230 basic_rates = 0;
231
232 for (i = 0; i < bss->supp_rates_len; i++) {
233 int rate = (bss->supp_rates[i] & 0x7f) * 5;
234 bool is_basic = !!(bss->supp_rates[i] & 0x80);
235
236 for (j = 0; j < sband->n_bitrates; j++) {
237 if (sband->bitrates[j].bitrate == rate) {
238 if (is_basic)
239 basic_rates |= BIT(j);
240 break;
241 }
242 }
243 }
244
245 __ieee80211_sta_join_ibss(sdata, cbss->bssid,
246 beacon_int,
247 cbss->channel,
248 basic_rates,
249 cbss->capability,
250 cbss->tsf);
251 }
252
ieee80211_ibss_finish_sta(struct sta_info * sta,bool auth)253 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta,
254 bool auth)
255 __acquires(RCU)
256 {
257 struct ieee80211_sub_if_data *sdata = sta->sdata;
258 u8 addr[ETH_ALEN];
259
260 memcpy(addr, sta->sta.addr, ETH_ALEN);
261
262 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
263 wiphy_debug(sdata->local->hw.wiphy,
264 "Adding new IBSS station %pM (dev=%s)\n",
265 addr, sdata->name);
266 #endif
267
268 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
269 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
270 /* authorize the station only if the network is not RSN protected. If
271 * not wait for the userspace to authorize it */
272 if (!sta->sdata->u.ibss.control_port)
273 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
274
275 rate_control_rate_init(sta);
276
277 /* If it fails, maybe we raced another insertion? */
278 if (sta_info_insert_rcu(sta))
279 return sta_info_get(sdata, addr);
280 if (auth) {
281 #ifdef CONFIG_MAC80211_IBSS_DEBUG
282 printk(KERN_DEBUG "TX Auth SA=%pM DA=%pM BSSID=%pM"
283 "(auth_transaction=1)\n", sdata->vif.addr,
284 sdata->u.ibss.bssid, addr);
285 #endif
286 ieee80211_send_auth(sdata, 1, WLAN_AUTH_OPEN, NULL, 0,
287 addr, sdata->u.ibss.bssid, NULL, 0, 0);
288 }
289 return sta;
290 }
291
292 static struct sta_info *
ieee80211_ibss_add_sta(struct ieee80211_sub_if_data * sdata,const u8 * bssid,const u8 * addr,u32 supp_rates,bool auth)293 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
294 const u8 *bssid, const u8 *addr,
295 u32 supp_rates, bool auth)
296 __acquires(RCU)
297 {
298 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
299 struct ieee80211_local *local = sdata->local;
300 struct sta_info *sta;
301 int band = local->hw.conf.channel->band;
302
303 /*
304 * XXX: Consider removing the least recently used entry and
305 * allow new one to be added.
306 */
307 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
308 if (net_ratelimit())
309 printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n",
310 sdata->name, addr);
311 rcu_read_lock();
312 return NULL;
313 }
314
315 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
316 rcu_read_lock();
317 return NULL;
318 }
319
320 if (compare_ether_addr(bssid, sdata->u.ibss.bssid)) {
321 rcu_read_lock();
322 return NULL;
323 }
324
325 sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
326 if (!sta) {
327 rcu_read_lock();
328 return NULL;
329 }
330
331 sta->last_rx = jiffies;
332
333 /* make sure mandatory rates are always added */
334 sta->sta.supp_rates[band] = supp_rates |
335 ieee80211_mandatory_rates(local, band);
336
337 return ieee80211_ibss_finish_sta(sta, auth);
338 }
339
ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data * sdata,struct ieee80211_mgmt * mgmt,size_t len)340 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
341 struct ieee80211_mgmt *mgmt,
342 size_t len)
343 {
344 u16 auth_alg, auth_transaction;
345
346 lockdep_assert_held(&sdata->u.ibss.mtx);
347
348 if (len < 24 + 6)
349 return;
350
351 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
352 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
353
354 if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
355 return;
356 #ifdef CONFIG_MAC80211_IBSS_DEBUG
357 printk(KERN_DEBUG "%s: RX Auth SA=%pM DA=%pM BSSID=%pM."
358 "(auth_transaction=%d)\n",
359 sdata->name, mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
360 #endif
361 sta_info_destroy_addr(sdata, mgmt->sa);
362 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false);
363 rcu_read_unlock();
364
365 /*
366 * IEEE 802.11 standard does not require authentication in IBSS
367 * networks and most implementations do not seem to use it.
368 * However, try to reply to authentication attempts if someone
369 * has actually implemented this.
370 */
371 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0,
372 mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0);
373 }
374
ieee80211_rx_bss_info(struct ieee80211_sub_if_data * sdata,struct ieee80211_mgmt * mgmt,size_t len,struct ieee80211_rx_status * rx_status,struct ieee802_11_elems * elems,bool beacon)375 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
376 struct ieee80211_mgmt *mgmt,
377 size_t len,
378 struct ieee80211_rx_status *rx_status,
379 struct ieee802_11_elems *elems,
380 bool beacon)
381 {
382 struct ieee80211_local *local = sdata->local;
383 int freq;
384 struct cfg80211_bss *cbss;
385 struct ieee80211_bss *bss;
386 struct sta_info *sta;
387 struct ieee80211_channel *channel;
388 u64 beacon_timestamp, rx_timestamp;
389 u32 supp_rates = 0;
390 enum ieee80211_band band = rx_status->band;
391 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
392 bool rates_updated = false;
393
394 if (elems->ds_params && elems->ds_params_len == 1)
395 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
396 band);
397 else
398 freq = rx_status->freq;
399
400 channel = ieee80211_get_channel(local->hw.wiphy, freq);
401
402 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
403 return;
404
405 if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
406 compare_ether_addr(mgmt->bssid, sdata->u.ibss.bssid) == 0) {
407
408 rcu_read_lock();
409 sta = sta_info_get(sdata, mgmt->sa);
410
411 if (elems->supp_rates) {
412 supp_rates = ieee80211_sta_get_rates(local, elems,
413 band);
414 if (sta) {
415 u32 prev_rates;
416
417 prev_rates = sta->sta.supp_rates[band];
418 /* make sure mandatory rates are always added */
419 sta->sta.supp_rates[band] = supp_rates |
420 ieee80211_mandatory_rates(local, band);
421
422 if (sta->sta.supp_rates[band] != prev_rates) {
423 #ifdef CONFIG_MAC80211_IBSS_DEBUG
424 printk(KERN_DEBUG
425 "%s: updated supp_rates set "
426 "for %pM based on beacon"
427 "/probe_resp (0x%x -> 0x%x)\n",
428 sdata->name, sta->sta.addr,
429 prev_rates,
430 sta->sta.supp_rates[band]);
431 #endif
432 rates_updated = true;
433 }
434 } else {
435 rcu_read_unlock();
436 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
437 mgmt->sa, supp_rates, true);
438 }
439 }
440
441 if (sta && elems->wmm_info)
442 set_sta_flag(sta, WLAN_STA_WME);
443
444 if (sta && elems->ht_info_elem && elems->ht_cap_elem &&
445 sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
446 /* we both use HT */
447 struct ieee80211_sta_ht_cap sta_ht_cap_new;
448 enum nl80211_channel_type channel_type =
449 ieee80211_ht_info_to_channel_type(
450 elems->ht_info_elem);
451
452 ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
453 elems->ht_cap_elem,
454 &sta_ht_cap_new);
455
456 /*
457 * fall back to HT20 if we don't use or use
458 * the other extension channel
459 */
460 if (!(channel_type == NL80211_CHAN_HT40MINUS ||
461 channel_type == NL80211_CHAN_HT40PLUS) ||
462 channel_type != sdata->u.ibss.channel_type)
463 sta_ht_cap_new.cap &=
464 ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
465
466 if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new,
467 sizeof(sta_ht_cap_new))) {
468 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new,
469 sizeof(sta_ht_cap_new));
470 rates_updated = true;
471 }
472 }
473
474 if (sta && rates_updated)
475 rate_control_rate_init(sta);
476
477 rcu_read_unlock();
478 }
479
480 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
481 channel, beacon);
482 if (!bss)
483 return;
484
485 cbss = container_of((void *)bss, struct cfg80211_bss, priv);
486
487 /* was just updated in ieee80211_bss_info_update */
488 beacon_timestamp = cbss->tsf;
489
490 /* check if we need to merge IBSS */
491
492 /* we use a fixed BSSID */
493 if (sdata->u.ibss.fixed_bssid)
494 goto put_bss;
495
496 /* not an IBSS */
497 if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
498 goto put_bss;
499
500 /* different channel */
501 if (cbss->channel != local->oper_channel)
502 goto put_bss;
503
504 /* different SSID */
505 if (elems->ssid_len != sdata->u.ibss.ssid_len ||
506 memcmp(elems->ssid, sdata->u.ibss.ssid,
507 sdata->u.ibss.ssid_len))
508 goto put_bss;
509
510 /* same BSSID */
511 if (compare_ether_addr(cbss->bssid, sdata->u.ibss.bssid) == 0)
512 goto put_bss;
513
514 if (rx_status->flag & RX_FLAG_MACTIME_MPDU) {
515 /*
516 * For correct IBSS merging we need mactime; since mactime is
517 * defined as the time the first data symbol of the frame hits
518 * the PHY, and the timestamp of the beacon is defined as "the
519 * time that the data symbol containing the first bit of the
520 * timestamp is transmitted to the PHY plus the transmitting
521 * STA's delays through its local PHY from the MAC-PHY
522 * interface to its interface with the WM" (802.11 11.1.2)
523 * - equals the time this bit arrives at the receiver - we have
524 * to take into account the offset between the two.
525 *
526 * E.g. at 1 MBit that means mactime is 192 usec earlier
527 * (=24 bytes * 8 usecs/byte) than the beacon timestamp.
528 */
529 int rate;
530
531 if (rx_status->flag & RX_FLAG_HT)
532 rate = 65; /* TODO: HT rates */
533 else
534 rate = local->hw.wiphy->bands[band]->
535 bitrates[rx_status->rate_idx].bitrate;
536
537 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate);
538 } else {
539 /*
540 * second best option: get current TSF
541 * (will return -1 if not supported)
542 */
543 rx_timestamp = drv_get_tsf(local, sdata);
544 }
545
546 #ifdef CONFIG_MAC80211_IBSS_DEBUG
547 printk(KERN_DEBUG "RX beacon SA=%pM BSSID="
548 "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
549 mgmt->sa, mgmt->bssid,
550 (unsigned long long)rx_timestamp,
551 (unsigned long long)beacon_timestamp,
552 (unsigned long long)(rx_timestamp - beacon_timestamp),
553 jiffies);
554 #endif
555
556 if (beacon_timestamp > rx_timestamp) {
557 #ifdef CONFIG_MAC80211_IBSS_DEBUG
558 printk(KERN_DEBUG "%s: beacon TSF higher than "
559 "local TSF - IBSS merge with BSSID %pM\n",
560 sdata->name, mgmt->bssid);
561 #endif
562 ieee80211_sta_join_ibss(sdata, bss);
563 supp_rates = ieee80211_sta_get_rates(local, elems, band);
564 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
565 supp_rates, true);
566 rcu_read_unlock();
567 }
568
569 put_bss:
570 ieee80211_rx_bss_put(local, bss);
571 }
572
ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data * sdata,const u8 * bssid,const u8 * addr,u32 supp_rates)573 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
574 const u8 *bssid, const u8 *addr,
575 u32 supp_rates)
576 {
577 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
578 struct ieee80211_local *local = sdata->local;
579 struct sta_info *sta;
580 int band = local->hw.conf.channel->band;
581
582 /*
583 * XXX: Consider removing the least recently used entry and
584 * allow new one to be added.
585 */
586 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
587 if (net_ratelimit())
588 printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n",
589 sdata->name, addr);
590 return;
591 }
592
593 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
594 return;
595
596 if (compare_ether_addr(bssid, sdata->u.ibss.bssid))
597 return;
598
599 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
600 if (!sta)
601 return;
602
603 sta->last_rx = jiffies;
604
605 /* make sure mandatory rates are always added */
606 sta->sta.supp_rates[band] = supp_rates |
607 ieee80211_mandatory_rates(local, band);
608
609 spin_lock(&ifibss->incomplete_lock);
610 list_add(&sta->list, &ifibss->incomplete_stations);
611 spin_unlock(&ifibss->incomplete_lock);
612 ieee80211_queue_work(&local->hw, &sdata->work);
613 }
614
ieee80211_sta_active_ibss(struct ieee80211_sub_if_data * sdata)615 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
616 {
617 struct ieee80211_local *local = sdata->local;
618 int active = 0;
619 struct sta_info *sta;
620
621 lockdep_assert_held(&sdata->u.ibss.mtx);
622
623 rcu_read_lock();
624
625 list_for_each_entry_rcu(sta, &local->sta_list, list) {
626 if (sta->sdata == sdata &&
627 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
628 jiffies)) {
629 active++;
630 break;
631 }
632 }
633
634 rcu_read_unlock();
635
636 return active;
637 }
638
639 /*
640 * This function is called with state == IEEE80211_IBSS_MLME_JOINED
641 */
642
ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data * sdata)643 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
644 {
645 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
646
647 lockdep_assert_held(&ifibss->mtx);
648
649 mod_timer(&ifibss->timer,
650 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
651
652 ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
653
654 if (time_before(jiffies, ifibss->last_scan_completed +
655 IEEE80211_IBSS_MERGE_INTERVAL))
656 return;
657
658 if (ieee80211_sta_active_ibss(sdata))
659 return;
660
661 if (ifibss->fixed_channel)
662 return;
663
664 printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other "
665 "IBSS networks with same SSID (merge)\n", sdata->name);
666
667 ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
668 NULL);
669 }
670
ieee80211_sta_create_ibss(struct ieee80211_sub_if_data * sdata)671 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
672 {
673 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
674 u8 bssid[ETH_ALEN];
675 u16 capability;
676 int i;
677
678 lockdep_assert_held(&ifibss->mtx);
679
680 if (ifibss->fixed_bssid) {
681 memcpy(bssid, ifibss->bssid, ETH_ALEN);
682 } else {
683 /* Generate random, not broadcast, locally administered BSSID. Mix in
684 * own MAC address to make sure that devices that do not have proper
685 * random number generator get different BSSID. */
686 get_random_bytes(bssid, ETH_ALEN);
687 for (i = 0; i < ETH_ALEN; i++)
688 bssid[i] ^= sdata->vif.addr[i];
689 bssid[0] &= ~0x01;
690 bssid[0] |= 0x02;
691 }
692
693 printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n",
694 sdata->name, bssid);
695
696 capability = WLAN_CAPABILITY_IBSS;
697
698 if (ifibss->privacy)
699 capability |= WLAN_CAPABILITY_PRIVACY;
700 else
701 sdata->drop_unencrypted = 0;
702
703 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
704 ifibss->channel, ifibss->basic_rates,
705 capability, 0);
706 }
707
708 /*
709 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
710 */
711
ieee80211_sta_find_ibss(struct ieee80211_sub_if_data * sdata)712 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
713 {
714 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
715 struct ieee80211_local *local = sdata->local;
716 struct cfg80211_bss *cbss;
717 struct ieee80211_channel *chan = NULL;
718 const u8 *bssid = NULL;
719 int active_ibss;
720 u16 capability;
721
722 lockdep_assert_held(&ifibss->mtx);
723
724 active_ibss = ieee80211_sta_active_ibss(sdata);
725 #ifdef CONFIG_MAC80211_IBSS_DEBUG
726 printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n",
727 sdata->name, active_ibss);
728 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
729
730 if (active_ibss)
731 return;
732
733 capability = WLAN_CAPABILITY_IBSS;
734 if (ifibss->privacy)
735 capability |= WLAN_CAPABILITY_PRIVACY;
736 if (ifibss->fixed_bssid)
737 bssid = ifibss->bssid;
738 if (ifibss->fixed_channel)
739 chan = ifibss->channel;
740 if (!is_zero_ether_addr(ifibss->bssid))
741 bssid = ifibss->bssid;
742 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
743 ifibss->ssid, ifibss->ssid_len,
744 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
745 capability);
746
747 if (cbss) {
748 struct ieee80211_bss *bss;
749
750 bss = (void *)cbss->priv;
751 #ifdef CONFIG_MAC80211_IBSS_DEBUG
752 printk(KERN_DEBUG " sta_find_ibss: selected %pM current "
753 "%pM\n", cbss->bssid, ifibss->bssid);
754 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
755
756 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM"
757 " based on configured SSID\n",
758 sdata->name, cbss->bssid);
759
760 ieee80211_sta_join_ibss(sdata, bss);
761 ieee80211_rx_bss_put(local, bss);
762 return;
763 }
764
765 #ifdef CONFIG_MAC80211_IBSS_DEBUG
766 printk(KERN_DEBUG " did not try to join ibss\n");
767 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
768
769 /* Selected IBSS not found in current scan results - try to scan */
770 if (time_after(jiffies, ifibss->last_scan_completed +
771 IEEE80211_SCAN_INTERVAL)) {
772 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to "
773 "join\n", sdata->name);
774
775 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
776 ifibss->ssid_len, chan);
777 } else {
778 int interval = IEEE80211_SCAN_INTERVAL;
779
780 if (time_after(jiffies, ifibss->ibss_join_req +
781 IEEE80211_IBSS_JOIN_TIMEOUT)) {
782 if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) {
783 ieee80211_sta_create_ibss(sdata);
784 return;
785 }
786 printk(KERN_DEBUG "%s: IBSS not allowed on"
787 " %d MHz\n", sdata->name,
788 local->hw.conf.channel->center_freq);
789
790 /* No IBSS found - decrease scan interval and continue
791 * scanning. */
792 interval = IEEE80211_SCAN_INTERVAL_SLOW;
793 }
794
795 mod_timer(&ifibss->timer,
796 round_jiffies(jiffies + interval));
797 }
798 }
799
ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data * sdata,struct sk_buff * req)800 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
801 struct sk_buff *req)
802 {
803 struct ieee80211_mgmt *mgmt = (void *)req->data;
804 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
805 struct ieee80211_local *local = sdata->local;
806 int tx_last_beacon, len = req->len;
807 struct sk_buff *skb;
808 struct ieee80211_mgmt *resp;
809 struct sk_buff *presp;
810 u8 *pos, *end;
811
812 lockdep_assert_held(&ifibss->mtx);
813
814 presp = rcu_dereference_protected(ifibss->presp,
815 lockdep_is_held(&ifibss->mtx));
816
817 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
818 len < 24 + 2 || !presp)
819 return;
820
821 tx_last_beacon = drv_tx_last_beacon(local);
822
823 #ifdef CONFIG_MAC80211_IBSS_DEBUG
824 printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM"
825 " (tx_last_beacon=%d)\n",
826 sdata->name, mgmt->sa, mgmt->da,
827 mgmt->bssid, tx_last_beacon);
828 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
829
830 if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
831 return;
832
833 if (compare_ether_addr(mgmt->bssid, ifibss->bssid) != 0 &&
834 !is_broadcast_ether_addr(mgmt->bssid))
835 return;
836
837 end = ((u8 *) mgmt) + len;
838 pos = mgmt->u.probe_req.variable;
839 if (pos[0] != WLAN_EID_SSID ||
840 pos + 2 + pos[1] > end) {
841 #ifdef CONFIG_MAC80211_IBSS_DEBUG
842 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq "
843 "from %pM\n",
844 sdata->name, mgmt->sa);
845 #endif
846 return;
847 }
848 if (pos[1] != 0 &&
849 (pos[1] != ifibss->ssid_len ||
850 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
851 /* Ignore ProbeReq for foreign SSID */
852 return;
853 }
854
855 /* Reply with ProbeResp */
856 skb = skb_copy(presp, GFP_KERNEL);
857 if (!skb)
858 return;
859
860 resp = (struct ieee80211_mgmt *) skb->data;
861 memcpy(resp->da, mgmt->sa, ETH_ALEN);
862 #ifdef CONFIG_MAC80211_IBSS_DEBUG
863 printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n",
864 sdata->name, resp->da);
865 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
866 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
867 ieee80211_tx_skb(sdata, skb);
868 }
869
ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data * sdata,struct ieee80211_mgmt * mgmt,size_t len,struct ieee80211_rx_status * rx_status)870 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
871 struct ieee80211_mgmt *mgmt,
872 size_t len,
873 struct ieee80211_rx_status *rx_status)
874 {
875 size_t baselen;
876 struct ieee802_11_elems elems;
877
878 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
879 if (baselen > len)
880 return;
881
882 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
883 &elems);
884
885 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
886 }
887
ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data * sdata,struct ieee80211_mgmt * mgmt,size_t len,struct ieee80211_rx_status * rx_status)888 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
889 struct ieee80211_mgmt *mgmt,
890 size_t len,
891 struct ieee80211_rx_status *rx_status)
892 {
893 size_t baselen;
894 struct ieee802_11_elems elems;
895
896 /* Process beacon from the current BSS */
897 baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
898 if (baselen > len)
899 return;
900
901 ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
902
903 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
904 }
905
ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb)906 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
907 struct sk_buff *skb)
908 {
909 struct ieee80211_rx_status *rx_status;
910 struct ieee80211_mgmt *mgmt;
911 u16 fc;
912
913 rx_status = IEEE80211_SKB_RXCB(skb);
914 mgmt = (struct ieee80211_mgmt *) skb->data;
915 fc = le16_to_cpu(mgmt->frame_control);
916
917 mutex_lock(&sdata->u.ibss.mtx);
918
919 if (!sdata->u.ibss.ssid_len)
920 goto mgmt_out; /* not ready to merge yet */
921
922 switch (fc & IEEE80211_FCTL_STYPE) {
923 case IEEE80211_STYPE_PROBE_REQ:
924 ieee80211_rx_mgmt_probe_req(sdata, skb);
925 break;
926 case IEEE80211_STYPE_PROBE_RESP:
927 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
928 rx_status);
929 break;
930 case IEEE80211_STYPE_BEACON:
931 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
932 rx_status);
933 break;
934 case IEEE80211_STYPE_AUTH:
935 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
936 break;
937 }
938
939 mgmt_out:
940 mutex_unlock(&sdata->u.ibss.mtx);
941 }
942
ieee80211_ibss_work(struct ieee80211_sub_if_data * sdata)943 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
944 {
945 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
946 struct sta_info *sta;
947
948 mutex_lock(&ifibss->mtx);
949
950 /*
951 * Work could be scheduled after scan or similar
952 * when we aren't even joined (or trying) with a
953 * network.
954 */
955 if (!ifibss->ssid_len)
956 goto out;
957
958 spin_lock_bh(&ifibss->incomplete_lock);
959 while (!list_empty(&ifibss->incomplete_stations)) {
960 sta = list_first_entry(&ifibss->incomplete_stations,
961 struct sta_info, list);
962 list_del(&sta->list);
963 spin_unlock_bh(&ifibss->incomplete_lock);
964
965 ieee80211_ibss_finish_sta(sta, true);
966 rcu_read_unlock();
967 spin_lock_bh(&ifibss->incomplete_lock);
968 }
969 spin_unlock_bh(&ifibss->incomplete_lock);
970
971 switch (ifibss->state) {
972 case IEEE80211_IBSS_MLME_SEARCH:
973 ieee80211_sta_find_ibss(sdata);
974 break;
975 case IEEE80211_IBSS_MLME_JOINED:
976 ieee80211_sta_merge_ibss(sdata);
977 break;
978 default:
979 WARN_ON(1);
980 break;
981 }
982
983 out:
984 mutex_unlock(&ifibss->mtx);
985 }
986
ieee80211_ibss_timer(unsigned long data)987 static void ieee80211_ibss_timer(unsigned long data)
988 {
989 struct ieee80211_sub_if_data *sdata =
990 (struct ieee80211_sub_if_data *) data;
991 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
992 struct ieee80211_local *local = sdata->local;
993
994 if (local->quiescing) {
995 ifibss->timer_running = true;
996 return;
997 }
998
999 ieee80211_queue_work(&local->hw, &sdata->work);
1000 }
1001
1002 #ifdef CONFIG_PM
ieee80211_ibss_quiesce(struct ieee80211_sub_if_data * sdata)1003 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
1004 {
1005 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1006
1007 if (del_timer_sync(&ifibss->timer))
1008 ifibss->timer_running = true;
1009 }
1010
ieee80211_ibss_restart(struct ieee80211_sub_if_data * sdata)1011 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
1012 {
1013 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1014
1015 if (ifibss->timer_running) {
1016 add_timer(&ifibss->timer);
1017 ifibss->timer_running = false;
1018 }
1019 }
1020 #endif
1021
ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data * sdata)1022 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1023 {
1024 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1025
1026 setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1027 (unsigned long) sdata);
1028 mutex_init(&ifibss->mtx);
1029 INIT_LIST_HEAD(&ifibss->incomplete_stations);
1030 spin_lock_init(&ifibss->incomplete_lock);
1031 }
1032
1033 /* scan finished notification */
ieee80211_ibss_notify_scan_completed(struct ieee80211_local * local)1034 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1035 {
1036 struct ieee80211_sub_if_data *sdata;
1037
1038 mutex_lock(&local->iflist_mtx);
1039 list_for_each_entry(sdata, &local->interfaces, list) {
1040 if (!ieee80211_sdata_running(sdata))
1041 continue;
1042 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1043 continue;
1044 sdata->u.ibss.last_scan_completed = jiffies;
1045 ieee80211_queue_work(&local->hw, &sdata->work);
1046 }
1047 mutex_unlock(&local->iflist_mtx);
1048 }
1049
ieee80211_ibss_join(struct ieee80211_sub_if_data * sdata,struct cfg80211_ibss_params * params)1050 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1051 struct cfg80211_ibss_params *params)
1052 {
1053 struct sk_buff *skb;
1054 u32 changed = 0;
1055
1056 skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1057 sizeof(struct ieee80211_hdr_3addr) +
1058 12 /* struct ieee80211_mgmt.u.beacon */ +
1059 2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1060 2 + 8 /* max Supported Rates */ +
1061 3 /* max DS params */ +
1062 4 /* IBSS params */ +
1063 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1064 2 + sizeof(struct ieee80211_ht_cap) +
1065 2 + sizeof(struct ieee80211_ht_info) +
1066 params->ie_len);
1067 if (!skb)
1068 return -ENOMEM;
1069
1070 mutex_lock(&sdata->u.ibss.mtx);
1071
1072 if (params->bssid) {
1073 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1074 sdata->u.ibss.fixed_bssid = true;
1075 } else
1076 sdata->u.ibss.fixed_bssid = false;
1077
1078 sdata->u.ibss.privacy = params->privacy;
1079 sdata->u.ibss.control_port = params->control_port;
1080 sdata->u.ibss.basic_rates = params->basic_rates;
1081 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1082 sizeof(params->mcast_rate));
1083
1084 sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1085
1086 sdata->u.ibss.channel = params->channel;
1087 sdata->u.ibss.channel_type = params->channel_type;
1088 sdata->u.ibss.fixed_channel = params->channel_fixed;
1089
1090 /* fix ourselves to that channel now already */
1091 if (params->channel_fixed) {
1092 sdata->local->oper_channel = params->channel;
1093 if (!ieee80211_set_channel_type(sdata->local, sdata,
1094 params->channel_type)) {
1095 mutex_unlock(&sdata->u.ibss.mtx);
1096 kfree_skb(skb);
1097 return -EINVAL;
1098 }
1099 }
1100
1101 if (params->ie) {
1102 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1103 GFP_KERNEL);
1104 if (sdata->u.ibss.ie)
1105 sdata->u.ibss.ie_len = params->ie_len;
1106 }
1107
1108 sdata->u.ibss.skb = skb;
1109 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1110 sdata->u.ibss.ibss_join_req = jiffies;
1111
1112 memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1113 sdata->u.ibss.ssid_len = params->ssid_len;
1114
1115 mutex_unlock(&sdata->u.ibss.mtx);
1116
1117 mutex_lock(&sdata->local->mtx);
1118 ieee80211_recalc_idle(sdata->local);
1119 mutex_unlock(&sdata->local->mtx);
1120
1121 /*
1122 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1123 * reserved, but an HT STA shall protect HT transmissions as though
1124 * the HT Protection field were set to non-HT mixed mode.
1125 *
1126 * In an IBSS, the RIFS Mode field of the HT Operation element is
1127 * also reserved, but an HT STA shall operate as though this field
1128 * were set to 1.
1129 */
1130
1131 sdata->vif.bss_conf.ht_operation_mode |=
1132 IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1133 | IEEE80211_HT_PARAM_RIFS_MODE;
1134
1135 changed |= BSS_CHANGED_HT;
1136 ieee80211_bss_info_change_notify(sdata, changed);
1137
1138 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1139
1140 return 0;
1141 }
1142
ieee80211_ibss_leave(struct ieee80211_sub_if_data * sdata)1143 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1144 {
1145 struct sk_buff *skb;
1146 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1147 struct ieee80211_local *local = sdata->local;
1148 struct cfg80211_bss *cbss;
1149 u16 capability;
1150 int active_ibss;
1151 struct sta_info *sta;
1152
1153 mutex_lock(&sdata->u.ibss.mtx);
1154
1155 active_ibss = ieee80211_sta_active_ibss(sdata);
1156
1157 if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1158 capability = WLAN_CAPABILITY_IBSS;
1159
1160 if (ifibss->privacy)
1161 capability |= WLAN_CAPABILITY_PRIVACY;
1162
1163 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel,
1164 ifibss->bssid, ifibss->ssid,
1165 ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1166 WLAN_CAPABILITY_PRIVACY,
1167 capability);
1168
1169 if (cbss) {
1170 cfg80211_unlink_bss(local->hw.wiphy, cbss);
1171 cfg80211_put_bss(cbss);
1172 }
1173 }
1174
1175 ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
1176 memset(ifibss->bssid, 0, ETH_ALEN);
1177 ifibss->ssid_len = 0;
1178
1179 sta_info_flush(sdata->local, sdata);
1180
1181 spin_lock_bh(&ifibss->incomplete_lock);
1182 while (!list_empty(&ifibss->incomplete_stations)) {
1183 sta = list_first_entry(&ifibss->incomplete_stations,
1184 struct sta_info, list);
1185 list_del(&sta->list);
1186 spin_unlock_bh(&ifibss->incomplete_lock);
1187
1188 sta_info_free(local, sta);
1189 spin_lock_bh(&ifibss->incomplete_lock);
1190 }
1191 spin_unlock_bh(&ifibss->incomplete_lock);
1192
1193 netif_carrier_off(sdata->dev);
1194
1195 /* remove beacon */
1196 kfree(sdata->u.ibss.ie);
1197 skb = rcu_dereference_protected(sdata->u.ibss.presp,
1198 lockdep_is_held(&sdata->u.ibss.mtx));
1199 RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1200 sdata->vif.bss_conf.ibss_joined = false;
1201 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1202 BSS_CHANGED_IBSS);
1203 synchronize_rcu();
1204 kfree_skb(skb);
1205
1206 skb_queue_purge(&sdata->skb_queue);
1207
1208 del_timer_sync(&sdata->u.ibss.timer);
1209
1210 mutex_unlock(&sdata->u.ibss.mtx);
1211
1212 mutex_lock(&local->mtx);
1213 ieee80211_recalc_idle(sdata->local);
1214 mutex_unlock(&local->mtx);
1215
1216 return 0;
1217 }
1218