Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless
[~shefty/rdma-dev.git] / net / mac80211 / ibss.c
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 #include <asm/unaligned.h>
24
25 #include "ieee80211_i.h"
26 #include "driver-ops.h"
27 #include "rate.h"
28
29 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
30 #define IEEE80211_SCAN_INTERVAL_SLOW (15 * HZ)
31 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
32
33 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
34 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
35
36 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
37
38
39 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
40                                         struct ieee80211_mgmt *mgmt,
41                                         size_t len)
42 {
43         u16 auth_alg, auth_transaction;
44
45         lockdep_assert_held(&sdata->u.ibss.mtx);
46
47         if (len < 24 + 6)
48                 return;
49
50         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
51         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
52
53         /*
54          * IEEE 802.11 standard does not require authentication in IBSS
55          * networks and most implementations do not seem to use it.
56          * However, try to reply to authentication attempts if someone
57          * has actually implemented this.
58          */
59         if (auth_alg == WLAN_AUTH_OPEN && auth_transaction == 1)
60                 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0,
61                                     sdata->u.ibss.bssid, NULL, 0, 0);
62 }
63
64 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
65                                       const u8 *bssid, const int beacon_int,
66                                       struct ieee80211_channel *chan,
67                                       const u32 basic_rates,
68                                       const u16 capability, u64 tsf)
69 {
70         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
71         struct ieee80211_local *local = sdata->local;
72         int rates, i;
73         struct sk_buff *skb;
74         struct ieee80211_mgmt *mgmt;
75         u8 *pos;
76         struct ieee80211_supported_band *sband;
77         struct cfg80211_bss *bss;
78         u32 bss_change;
79         u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
80         enum nl80211_channel_type channel_type;
81
82         lockdep_assert_held(&ifibss->mtx);
83
84         /* Reset own TSF to allow time synchronization work. */
85         drv_reset_tsf(local, sdata);
86
87         skb = ifibss->skb;
88         RCU_INIT_POINTER(ifibss->presp, NULL);
89         synchronize_rcu();
90         skb->data = skb->head;
91         skb->len = 0;
92         skb_reset_tail_pointer(skb);
93         skb_reserve(skb, sdata->local->hw.extra_tx_headroom);
94
95         if (memcmp(ifibss->bssid, bssid, ETH_ALEN))
96                 sta_info_flush(sdata->local, sdata);
97
98         /* if merging, indicate to driver that we leave the old IBSS */
99         if (sdata->vif.bss_conf.ibss_joined) {
100                 sdata->vif.bss_conf.ibss_joined = false;
101                 netif_carrier_off(sdata->dev);
102                 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS);
103         }
104
105         memcpy(ifibss->bssid, bssid, ETH_ALEN);
106
107         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
108
109         local->oper_channel = chan;
110         channel_type = ifibss->channel_type;
111         if (channel_type > NL80211_CHAN_HT20 &&
112             !cfg80211_can_beacon_sec_chan(local->hw.wiphy, chan, channel_type))
113                 channel_type = NL80211_CHAN_HT20;
114         if (!ieee80211_set_channel_type(local, sdata, channel_type)) {
115                 /* can only fail due to HT40+/- mismatch */
116                 channel_type = NL80211_CHAN_HT20;
117                 WARN_ON(!ieee80211_set_channel_type(local, sdata,
118                                                     NL80211_CHAN_HT20));
119         }
120         ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
121
122         sband = local->hw.wiphy->bands[chan->band];
123
124         /* build supported rates array */
125         pos = supp_rates;
126         for (i = 0; i < sband->n_bitrates; i++) {
127                 int rate = sband->bitrates[i].bitrate;
128                 u8 basic = 0;
129                 if (basic_rates & BIT(i))
130                         basic = 0x80;
131                 *pos++ = basic | (u8) (rate / 5);
132         }
133
134         /* Build IBSS probe response */
135         mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
136         memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
137         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
138                                           IEEE80211_STYPE_PROBE_RESP);
139         memset(mgmt->da, 0xff, ETH_ALEN);
140         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
141         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
142         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
143         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
144         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
145
146         pos = skb_put(skb, 2 + ifibss->ssid_len);
147         *pos++ = WLAN_EID_SSID;
148         *pos++ = ifibss->ssid_len;
149         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
150
151         rates = sband->n_bitrates;
152         if (rates > 8)
153                 rates = 8;
154         pos = skb_put(skb, 2 + rates);
155         *pos++ = WLAN_EID_SUPP_RATES;
156         *pos++ = rates;
157         memcpy(pos, supp_rates, rates);
158
159         if (sband->band == IEEE80211_BAND_2GHZ) {
160                 pos = skb_put(skb, 2 + 1);
161                 *pos++ = WLAN_EID_DS_PARAMS;
162                 *pos++ = 1;
163                 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
164         }
165
166         pos = skb_put(skb, 2 + 2);
167         *pos++ = WLAN_EID_IBSS_PARAMS;
168         *pos++ = 2;
169         /* FIX: set ATIM window based on scan results */
170         *pos++ = 0;
171         *pos++ = 0;
172
173         if (sband->n_bitrates > 8) {
174                 rates = sband->n_bitrates - 8;
175                 pos = skb_put(skb, 2 + rates);
176                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
177                 *pos++ = rates;
178                 memcpy(pos, &supp_rates[8], rates);
179         }
180
181         if (ifibss->ie_len)
182                 memcpy(skb_put(skb, ifibss->ie_len),
183                        ifibss->ie, ifibss->ie_len);
184
185         /* add HT capability and information IEs */
186         if (channel_type && sband->ht_cap.ht_supported) {
187                 pos = skb_put(skb, 4 +
188                                    sizeof(struct ieee80211_ht_cap) +
189                                    sizeof(struct ieee80211_ht_info));
190                 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
191                                                 sband->ht_cap.cap);
192                 pos = ieee80211_ie_build_ht_info(pos,
193                                                  &sband->ht_cap,
194                                                  chan,
195                                                  channel_type);
196         }
197
198         if (local->hw.queues >= 4) {
199                 pos = skb_put(skb, 9);
200                 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
201                 *pos++ = 7; /* len */
202                 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
203                 *pos++ = 0x50;
204                 *pos++ = 0xf2;
205                 *pos++ = 2; /* WME */
206                 *pos++ = 0; /* WME info */
207                 *pos++ = 1; /* WME ver */
208                 *pos++ = 0; /* U-APSD no in use */
209         }
210
211         rcu_assign_pointer(ifibss->presp, skb);
212
213         sdata->vif.bss_conf.beacon_int = beacon_int;
214         sdata->vif.bss_conf.basic_rates = basic_rates;
215         bss_change = BSS_CHANGED_BEACON_INT;
216         bss_change |= ieee80211_reset_erp_info(sdata);
217         bss_change |= BSS_CHANGED_BSSID;
218         bss_change |= BSS_CHANGED_BEACON;
219         bss_change |= BSS_CHANGED_BEACON_ENABLED;
220         bss_change |= BSS_CHANGED_BASIC_RATES;
221         bss_change |= BSS_CHANGED_HT;
222         bss_change |= BSS_CHANGED_IBSS;
223         sdata->vif.bss_conf.ibss_joined = true;
224         ieee80211_bss_info_change_notify(sdata, bss_change);
225
226         ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
227
228         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
229         mod_timer(&ifibss->timer,
230                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
231
232         bss = cfg80211_inform_bss_frame(local->hw.wiphy, local->hw.conf.channel,
233                                         mgmt, skb->len, 0, GFP_KERNEL);
234         cfg80211_put_bss(bss);
235         netif_carrier_on(sdata->dev);
236         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
237 }
238
239 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
240                                     struct ieee80211_bss *bss)
241 {
242         struct cfg80211_bss *cbss =
243                 container_of((void *)bss, struct cfg80211_bss, priv);
244         struct ieee80211_supported_band *sband;
245         u32 basic_rates;
246         int i, j;
247         u16 beacon_int = cbss->beacon_interval;
248
249         lockdep_assert_held(&sdata->u.ibss.mtx);
250
251         if (beacon_int < 10)
252                 beacon_int = 10;
253
254         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
255
256         basic_rates = 0;
257
258         for (i = 0; i < bss->supp_rates_len; i++) {
259                 int rate = (bss->supp_rates[i] & 0x7f) * 5;
260                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
261
262                 for (j = 0; j < sband->n_bitrates; j++) {
263                         if (sband->bitrates[j].bitrate == rate) {
264                                 if (is_basic)
265                                         basic_rates |= BIT(j);
266                                 break;
267                         }
268                 }
269         }
270
271         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
272                                   beacon_int,
273                                   cbss->channel,
274                                   basic_rates,
275                                   cbss->capability,
276                                   cbss->tsf);
277 }
278
279 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
280         __acquires(RCU)
281 {
282         struct ieee80211_sub_if_data *sdata = sta->sdata;
283         u8 addr[ETH_ALEN];
284
285         memcpy(addr, sta->sta.addr, ETH_ALEN);
286
287 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
288         wiphy_debug(sdata->local->hw.wiphy,
289                     "Adding new IBSS station %pM (dev=%s)\n",
290                     addr, sdata->name);
291 #endif
292
293         sta_info_move_state(sta, IEEE80211_STA_AUTH);
294         sta_info_move_state(sta, IEEE80211_STA_ASSOC);
295         sta_info_move_state(sta, IEEE80211_STA_AUTHORIZED);
296
297         rate_control_rate_init(sta);
298
299         /* If it fails, maybe we raced another insertion? */
300         if (sta_info_insert_rcu(sta))
301                 return sta_info_get(sdata, addr);
302         return sta;
303 }
304
305 static struct sta_info *
306 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
307                        const u8 *bssid, const u8 *addr,
308                        u32 supp_rates)
309         __acquires(RCU)
310 {
311         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
312         struct ieee80211_local *local = sdata->local;
313         struct sta_info *sta;
314         int band = local->hw.conf.channel->band;
315
316         /*
317          * XXX: Consider removing the least recently used entry and
318          *      allow new one to be added.
319          */
320         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
321                 if (net_ratelimit())
322                         printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n",
323                                sdata->name, addr);
324                 rcu_read_lock();
325                 return NULL;
326         }
327
328         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
329                 rcu_read_lock();
330                 return NULL;
331         }
332
333         if (compare_ether_addr(bssid, sdata->u.ibss.bssid)) {
334                 rcu_read_lock();
335                 return NULL;
336         }
337
338         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
339         if (!sta) {
340                 rcu_read_lock();
341                 return NULL;
342         }
343
344         sta->last_rx = jiffies;
345
346         /* make sure mandatory rates are always added */
347         sta->sta.supp_rates[band] = supp_rates |
348                         ieee80211_mandatory_rates(local, band);
349
350         return ieee80211_ibss_finish_sta(sta);
351 }
352
353 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
354                                   struct ieee80211_mgmt *mgmt,
355                                   size_t len,
356                                   struct ieee80211_rx_status *rx_status,
357                                   struct ieee802_11_elems *elems,
358                                   bool beacon)
359 {
360         struct ieee80211_local *local = sdata->local;
361         int freq;
362         struct cfg80211_bss *cbss;
363         struct ieee80211_bss *bss;
364         struct sta_info *sta;
365         struct ieee80211_channel *channel;
366         u64 beacon_timestamp, rx_timestamp;
367         u32 supp_rates = 0;
368         enum ieee80211_band band = rx_status->band;
369         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
370         bool rates_updated = false;
371
372         if (elems->ds_params && elems->ds_params_len == 1)
373                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
374                                                       band);
375         else
376                 freq = rx_status->freq;
377
378         channel = ieee80211_get_channel(local->hw.wiphy, freq);
379
380         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
381                 return;
382
383         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
384             memcmp(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) {
385
386                 rcu_read_lock();
387                 sta = sta_info_get(sdata, mgmt->sa);
388
389                 if (elems->supp_rates) {
390                         supp_rates = ieee80211_sta_get_rates(local, elems,
391                                                              band);
392                         if (sta) {
393                                 u32 prev_rates;
394
395                                 prev_rates = sta->sta.supp_rates[band];
396                                 /* make sure mandatory rates are always added */
397                                 sta->sta.supp_rates[band] = supp_rates |
398                                         ieee80211_mandatory_rates(local, band);
399
400                                 if (sta->sta.supp_rates[band] != prev_rates) {
401 #ifdef CONFIG_MAC80211_IBSS_DEBUG
402                                         printk(KERN_DEBUG
403                                                 "%s: updated supp_rates set "
404                                                 "for %pM based on beacon"
405                                                 "/probe_resp (0x%x -> 0x%x)\n",
406                                                 sdata->name, sta->sta.addr,
407                                                 prev_rates,
408                                                 sta->sta.supp_rates[band]);
409 #endif
410                                         rates_updated = true;
411                                 }
412                         } else {
413                                 rcu_read_unlock();
414                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
415                                                 mgmt->sa, supp_rates);
416                         }
417                 }
418
419                 if (sta && elems->wmm_info)
420                         set_sta_flag(sta, WLAN_STA_WME);
421
422                 if (sta && elems->ht_info_elem && elems->ht_cap_elem &&
423                     sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
424                         /* we both use HT */
425                         struct ieee80211_sta_ht_cap sta_ht_cap_new;
426                         enum nl80211_channel_type channel_type =
427                                 ieee80211_ht_info_to_channel_type(
428                                                         elems->ht_info_elem);
429
430                         ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
431                                                           elems->ht_cap_elem,
432                                                           &sta_ht_cap_new);
433
434                         /*
435                          * fall back to HT20 if we don't use or use
436                          * the other extension channel
437                          */
438                         if ((channel_type == NL80211_CHAN_HT40MINUS ||
439                              channel_type == NL80211_CHAN_HT40PLUS) &&
440                             channel_type != sdata->u.ibss.channel_type)
441                                 sta_ht_cap_new.cap &=
442                                         ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
443
444                         if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new,
445                                    sizeof(sta_ht_cap_new))) {
446                                 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new,
447                                        sizeof(sta_ht_cap_new));
448                                 rates_updated = true;
449                         }
450                 }
451
452                 if (sta && rates_updated)
453                         rate_control_rate_init(sta);
454
455                 rcu_read_unlock();
456         }
457
458         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
459                                         channel, beacon);
460         if (!bss)
461                 return;
462
463         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
464
465         /* was just updated in ieee80211_bss_info_update */
466         beacon_timestamp = cbss->tsf;
467
468         /* check if we need to merge IBSS */
469
470         /* we use a fixed BSSID */
471         if (sdata->u.ibss.fixed_bssid)
472                 goto put_bss;
473
474         /* not an IBSS */
475         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
476                 goto put_bss;
477
478         /* different channel */
479         if (cbss->channel != local->oper_channel)
480                 goto put_bss;
481
482         /* different SSID */
483         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
484             memcmp(elems->ssid, sdata->u.ibss.ssid,
485                                 sdata->u.ibss.ssid_len))
486                 goto put_bss;
487
488         /* same BSSID */
489         if (memcmp(cbss->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0)
490                 goto put_bss;
491
492         if (rx_status->flag & RX_FLAG_MACTIME_MPDU) {
493                 /*
494                  * For correct IBSS merging we need mactime; since mactime is
495                  * defined as the time the first data symbol of the frame hits
496                  * the PHY, and the timestamp of the beacon is defined as "the
497                  * time that the data symbol containing the first bit of the
498                  * timestamp is transmitted to the PHY plus the transmitting
499                  * STA's delays through its local PHY from the MAC-PHY
500                  * interface to its interface with the WM" (802.11 11.1.2)
501                  * - equals the time this bit arrives at the receiver - we have
502                  * to take into account the offset between the two.
503                  *
504                  * E.g. at 1 MBit that means mactime is 192 usec earlier
505                  * (=24 bytes * 8 usecs/byte) than the beacon timestamp.
506                  */
507                 int rate;
508
509                 if (rx_status->flag & RX_FLAG_HT)
510                         rate = 65; /* TODO: HT rates */
511                 else
512                         rate = local->hw.wiphy->bands[band]->
513                                 bitrates[rx_status->rate_idx].bitrate;
514
515                 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate);
516         } else {
517                 /*
518                  * second best option: get current TSF
519                  * (will return -1 if not supported)
520                  */
521                 rx_timestamp = drv_get_tsf(local, sdata);
522         }
523
524 #ifdef CONFIG_MAC80211_IBSS_DEBUG
525         printk(KERN_DEBUG "RX beacon SA=%pM BSSID="
526                "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
527                mgmt->sa, mgmt->bssid,
528                (unsigned long long)rx_timestamp,
529                (unsigned long long)beacon_timestamp,
530                (unsigned long long)(rx_timestamp - beacon_timestamp),
531                jiffies);
532 #endif
533
534         if (beacon_timestamp > rx_timestamp) {
535 #ifdef CONFIG_MAC80211_IBSS_DEBUG
536                 printk(KERN_DEBUG "%s: beacon TSF higher than "
537                        "local TSF - IBSS merge with BSSID %pM\n",
538                        sdata->name, mgmt->bssid);
539 #endif
540                 ieee80211_sta_join_ibss(sdata, bss);
541                 supp_rates = ieee80211_sta_get_rates(local, elems, band);
542                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
543                                        supp_rates);
544                 rcu_read_unlock();
545         }
546
547  put_bss:
548         ieee80211_rx_bss_put(local, bss);
549 }
550
551 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
552                               const u8 *bssid, const u8 *addr,
553                               u32 supp_rates)
554 {
555         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
556         struct ieee80211_local *local = sdata->local;
557         struct sta_info *sta;
558         int band = local->hw.conf.channel->band;
559
560         /*
561          * XXX: Consider removing the least recently used entry and
562          *      allow new one to be added.
563          */
564         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
565                 if (net_ratelimit())
566                         printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n",
567                                sdata->name, addr);
568                 return;
569         }
570
571         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
572                 return;
573
574         if (compare_ether_addr(bssid, sdata->u.ibss.bssid))
575                 return;
576
577         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
578         if (!sta)
579                 return;
580
581         sta->last_rx = jiffies;
582
583         /* make sure mandatory rates are always added */
584         sta->sta.supp_rates[band] = supp_rates |
585                         ieee80211_mandatory_rates(local, band);
586
587         spin_lock(&ifibss->incomplete_lock);
588         list_add(&sta->list, &ifibss->incomplete_stations);
589         spin_unlock(&ifibss->incomplete_lock);
590         ieee80211_queue_work(&local->hw, &sdata->work);
591 }
592
593 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
594 {
595         struct ieee80211_local *local = sdata->local;
596         int active = 0;
597         struct sta_info *sta;
598
599         lockdep_assert_held(&sdata->u.ibss.mtx);
600
601         rcu_read_lock();
602
603         list_for_each_entry_rcu(sta, &local->sta_list, list) {
604                 if (sta->sdata == sdata &&
605                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
606                                jiffies)) {
607                         active++;
608                         break;
609                 }
610         }
611
612         rcu_read_unlock();
613
614         return active;
615 }
616
617 /*
618  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
619  */
620
621 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
622 {
623         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
624
625         lockdep_assert_held(&ifibss->mtx);
626
627         mod_timer(&ifibss->timer,
628                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
629
630         ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
631
632         if (time_before(jiffies, ifibss->last_scan_completed +
633                        IEEE80211_IBSS_MERGE_INTERVAL))
634                 return;
635
636         if (ieee80211_sta_active_ibss(sdata))
637                 return;
638
639         if (ifibss->fixed_channel)
640                 return;
641
642         printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other "
643                "IBSS networks with same SSID (merge)\n", sdata->name);
644
645         ieee80211_request_internal_scan(sdata,
646                         ifibss->ssid, ifibss->ssid_len,
647                         ifibss->fixed_channel ? ifibss->channel : NULL);
648 }
649
650 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
651 {
652         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
653         u8 bssid[ETH_ALEN];
654         u16 capability;
655         int i;
656
657         lockdep_assert_held(&ifibss->mtx);
658
659         if (ifibss->fixed_bssid) {
660                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
661         } else {
662                 /* Generate random, not broadcast, locally administered BSSID. Mix in
663                  * own MAC address to make sure that devices that do not have proper
664                  * random number generator get different BSSID. */
665                 get_random_bytes(bssid, ETH_ALEN);
666                 for (i = 0; i < ETH_ALEN; i++)
667                         bssid[i] ^= sdata->vif.addr[i];
668                 bssid[0] &= ~0x01;
669                 bssid[0] |= 0x02;
670         }
671
672         printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n",
673                sdata->name, bssid);
674
675         capability = WLAN_CAPABILITY_IBSS;
676
677         if (ifibss->privacy)
678                 capability |= WLAN_CAPABILITY_PRIVACY;
679         else
680                 sdata->drop_unencrypted = 0;
681
682         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
683                                   ifibss->channel, ifibss->basic_rates,
684                                   capability, 0);
685 }
686
687 /*
688  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
689  */
690
691 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
692 {
693         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
694         struct ieee80211_local *local = sdata->local;
695         struct cfg80211_bss *cbss;
696         struct ieee80211_channel *chan = NULL;
697         const u8 *bssid = NULL;
698         int active_ibss;
699         u16 capability;
700
701         lockdep_assert_held(&ifibss->mtx);
702
703         active_ibss = ieee80211_sta_active_ibss(sdata);
704 #ifdef CONFIG_MAC80211_IBSS_DEBUG
705         printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n",
706                sdata->name, active_ibss);
707 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
708
709         if (active_ibss)
710                 return;
711
712         capability = WLAN_CAPABILITY_IBSS;
713         if (ifibss->privacy)
714                 capability |= WLAN_CAPABILITY_PRIVACY;
715         if (ifibss->fixed_bssid)
716                 bssid = ifibss->bssid;
717         if (ifibss->fixed_channel)
718                 chan = ifibss->channel;
719         if (!is_zero_ether_addr(ifibss->bssid))
720                 bssid = ifibss->bssid;
721         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
722                                 ifibss->ssid, ifibss->ssid_len,
723                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
724                                 capability);
725
726         if (cbss) {
727                 struct ieee80211_bss *bss;
728
729                 bss = (void *)cbss->priv;
730 #ifdef CONFIG_MAC80211_IBSS_DEBUG
731                 printk(KERN_DEBUG "   sta_find_ibss: selected %pM current "
732                        "%pM\n", cbss->bssid, ifibss->bssid);
733 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
734
735                 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM"
736                        " based on configured SSID\n",
737                        sdata->name, cbss->bssid);
738
739                 ieee80211_sta_join_ibss(sdata, bss);
740                 ieee80211_rx_bss_put(local, bss);
741                 return;
742         }
743
744 #ifdef CONFIG_MAC80211_IBSS_DEBUG
745         printk(KERN_DEBUG "   did not try to join ibss\n");
746 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
747
748         /* Selected IBSS not found in current scan results - try to scan */
749         if (time_after(jiffies, ifibss->last_scan_completed +
750                                         IEEE80211_SCAN_INTERVAL)) {
751                 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to "
752                        "join\n", sdata->name);
753
754                 ieee80211_request_internal_scan(sdata,
755                                 ifibss->ssid, ifibss->ssid_len,
756                                 ifibss->fixed_channel ? ifibss->channel : NULL);
757         } else {
758                 int interval = IEEE80211_SCAN_INTERVAL;
759
760                 if (time_after(jiffies, ifibss->ibss_join_req +
761                                IEEE80211_IBSS_JOIN_TIMEOUT)) {
762                         if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) {
763                                 ieee80211_sta_create_ibss(sdata);
764                                 return;
765                         }
766                         printk(KERN_DEBUG "%s: IBSS not allowed on"
767                                " %d MHz\n", sdata->name,
768                                local->hw.conf.channel->center_freq);
769
770                         /* No IBSS found - decrease scan interval and continue
771                          * scanning. */
772                         interval = IEEE80211_SCAN_INTERVAL_SLOW;
773                 }
774
775                 mod_timer(&ifibss->timer,
776                           round_jiffies(jiffies + interval));
777         }
778 }
779
780 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
781                                         struct sk_buff *req)
782 {
783         struct ieee80211_mgmt *mgmt = (void *)req->data;
784         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
785         struct ieee80211_local *local = sdata->local;
786         int tx_last_beacon, len = req->len;
787         struct sk_buff *skb;
788         struct ieee80211_mgmt *resp;
789         struct sk_buff *presp;
790         u8 *pos, *end;
791
792         lockdep_assert_held(&ifibss->mtx);
793
794         presp = rcu_dereference_protected(ifibss->presp,
795                                           lockdep_is_held(&ifibss->mtx));
796
797         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
798             len < 24 + 2 || !presp)
799                 return;
800
801         tx_last_beacon = drv_tx_last_beacon(local);
802
803 #ifdef CONFIG_MAC80211_IBSS_DEBUG
804         printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM"
805                " (tx_last_beacon=%d)\n",
806                sdata->name, mgmt->sa, mgmt->da,
807                mgmt->bssid, tx_last_beacon);
808 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
809
810         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
811                 return;
812
813         if (memcmp(mgmt->bssid, ifibss->bssid, ETH_ALEN) != 0 &&
814             memcmp(mgmt->bssid, "\xff\xff\xff\xff\xff\xff", ETH_ALEN) != 0)
815                 return;
816
817         end = ((u8 *) mgmt) + len;
818         pos = mgmt->u.probe_req.variable;
819         if (pos[0] != WLAN_EID_SSID ||
820             pos + 2 + pos[1] > end) {
821 #ifdef CONFIG_MAC80211_IBSS_DEBUG
822                 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq "
823                        "from %pM\n",
824                        sdata->name, mgmt->sa);
825 #endif
826                 return;
827         }
828         if (pos[1] != 0 &&
829             (pos[1] != ifibss->ssid_len ||
830              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
831                 /* Ignore ProbeReq for foreign SSID */
832                 return;
833         }
834
835         /* Reply with ProbeResp */
836         skb = skb_copy(presp, GFP_KERNEL);
837         if (!skb)
838                 return;
839
840         resp = (struct ieee80211_mgmt *) skb->data;
841         memcpy(resp->da, mgmt->sa, ETH_ALEN);
842 #ifdef CONFIG_MAC80211_IBSS_DEBUG
843         printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n",
844                sdata->name, resp->da);
845 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
846         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
847         ieee80211_tx_skb(sdata, skb);
848 }
849
850 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
851                                          struct ieee80211_mgmt *mgmt,
852                                          size_t len,
853                                          struct ieee80211_rx_status *rx_status)
854 {
855         size_t baselen;
856         struct ieee802_11_elems elems;
857
858         if (memcmp(mgmt->da, sdata->vif.addr, ETH_ALEN))
859                 return; /* ignore ProbeResp to foreign address */
860
861         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
862         if (baselen > len)
863                 return;
864
865         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
866                                 &elems);
867
868         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
869 }
870
871 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
872                                      struct ieee80211_mgmt *mgmt,
873                                      size_t len,
874                                      struct ieee80211_rx_status *rx_status)
875 {
876         size_t baselen;
877         struct ieee802_11_elems elems;
878
879         /* Process beacon from the current BSS */
880         baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
881         if (baselen > len)
882                 return;
883
884         ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
885
886         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
887 }
888
889 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
890                                    struct sk_buff *skb)
891 {
892         struct ieee80211_rx_status *rx_status;
893         struct ieee80211_mgmt *mgmt;
894         u16 fc;
895
896         rx_status = IEEE80211_SKB_RXCB(skb);
897         mgmt = (struct ieee80211_mgmt *) skb->data;
898         fc = le16_to_cpu(mgmt->frame_control);
899
900         mutex_lock(&sdata->u.ibss.mtx);
901
902         if (!sdata->u.ibss.ssid_len)
903                 goto mgmt_out; /* not ready to merge yet */
904
905         switch (fc & IEEE80211_FCTL_STYPE) {
906         case IEEE80211_STYPE_PROBE_REQ:
907                 ieee80211_rx_mgmt_probe_req(sdata, skb);
908                 break;
909         case IEEE80211_STYPE_PROBE_RESP:
910                 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
911                                              rx_status);
912                 break;
913         case IEEE80211_STYPE_BEACON:
914                 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
915                                          rx_status);
916                 break;
917         case IEEE80211_STYPE_AUTH:
918                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
919                 break;
920         }
921
922  mgmt_out:
923         mutex_unlock(&sdata->u.ibss.mtx);
924 }
925
926 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
927 {
928         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
929         struct sta_info *sta;
930
931         mutex_lock(&ifibss->mtx);
932
933         /*
934          * Work could be scheduled after scan or similar
935          * when we aren't even joined (or trying) with a
936          * network.
937          */
938         if (!ifibss->ssid_len)
939                 goto out;
940
941         spin_lock_bh(&ifibss->incomplete_lock);
942         while (!list_empty(&ifibss->incomplete_stations)) {
943                 sta = list_first_entry(&ifibss->incomplete_stations,
944                                        struct sta_info, list);
945                 list_del(&sta->list);
946                 spin_unlock_bh(&ifibss->incomplete_lock);
947
948                 ieee80211_ibss_finish_sta(sta);
949                 rcu_read_unlock();
950                 spin_lock_bh(&ifibss->incomplete_lock);
951         }
952         spin_unlock_bh(&ifibss->incomplete_lock);
953
954         switch (ifibss->state) {
955         case IEEE80211_IBSS_MLME_SEARCH:
956                 ieee80211_sta_find_ibss(sdata);
957                 break;
958         case IEEE80211_IBSS_MLME_JOINED:
959                 ieee80211_sta_merge_ibss(sdata);
960                 break;
961         default:
962                 WARN_ON(1);
963                 break;
964         }
965
966  out:
967         mutex_unlock(&ifibss->mtx);
968 }
969
970 static void ieee80211_ibss_timer(unsigned long data)
971 {
972         struct ieee80211_sub_if_data *sdata =
973                 (struct ieee80211_sub_if_data *) data;
974         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
975         struct ieee80211_local *local = sdata->local;
976
977         if (local->quiescing) {
978                 ifibss->timer_running = true;
979                 return;
980         }
981
982         ieee80211_queue_work(&local->hw, &sdata->work);
983 }
984
985 #ifdef CONFIG_PM
986 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
987 {
988         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
989
990         if (del_timer_sync(&ifibss->timer))
991                 ifibss->timer_running = true;
992 }
993
994 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
995 {
996         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
997
998         if (ifibss->timer_running) {
999                 add_timer(&ifibss->timer);
1000                 ifibss->timer_running = false;
1001         }
1002 }
1003 #endif
1004
1005 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1006 {
1007         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1008
1009         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1010                     (unsigned long) sdata);
1011         mutex_init(&ifibss->mtx);
1012         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1013         spin_lock_init(&ifibss->incomplete_lock);
1014 }
1015
1016 /* scan finished notification */
1017 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1018 {
1019         struct ieee80211_sub_if_data *sdata;
1020
1021         mutex_lock(&local->iflist_mtx);
1022         list_for_each_entry(sdata, &local->interfaces, list) {
1023                 if (!ieee80211_sdata_running(sdata))
1024                         continue;
1025                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1026                         continue;
1027                 sdata->u.ibss.last_scan_completed = jiffies;
1028                 ieee80211_queue_work(&local->hw, &sdata->work);
1029         }
1030         mutex_unlock(&local->iflist_mtx);
1031 }
1032
1033 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1034                         struct cfg80211_ibss_params *params)
1035 {
1036         struct sk_buff *skb;
1037         u32 changed = 0;
1038
1039         skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1040                             sizeof(struct ieee80211_hdr_3addr) +
1041                             12 /* struct ieee80211_mgmt.u.beacon */ +
1042                             2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1043                             2 + 8 /* max Supported Rates */ +
1044                             3 /* max DS params */ +
1045                             4 /* IBSS params */ +
1046                             2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1047                             2 + sizeof(struct ieee80211_ht_cap) +
1048                             2 + sizeof(struct ieee80211_ht_info) +
1049                             params->ie_len);
1050         if (!skb)
1051                 return -ENOMEM;
1052
1053         mutex_lock(&sdata->u.ibss.mtx);
1054
1055         if (params->bssid) {
1056                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1057                 sdata->u.ibss.fixed_bssid = true;
1058         } else
1059                 sdata->u.ibss.fixed_bssid = false;
1060
1061         sdata->u.ibss.privacy = params->privacy;
1062         sdata->u.ibss.basic_rates = params->basic_rates;
1063         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1064                sizeof(params->mcast_rate));
1065
1066         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1067
1068         sdata->u.ibss.channel = params->channel;
1069         sdata->u.ibss.channel_type = params->channel_type;
1070         sdata->u.ibss.fixed_channel = params->channel_fixed;
1071
1072         /* fix ourselves to that channel now already */
1073         if (params->channel_fixed) {
1074                 sdata->local->oper_channel = params->channel;
1075                 if (!ieee80211_set_channel_type(sdata->local, sdata,
1076                                                params->channel_type)) {
1077                         mutex_unlock(&sdata->u.ibss.mtx);
1078                         kfree_skb(skb);
1079                         return -EINVAL;
1080                 }
1081         }
1082
1083         if (params->ie) {
1084                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1085                                            GFP_KERNEL);
1086                 if (sdata->u.ibss.ie)
1087                         sdata->u.ibss.ie_len = params->ie_len;
1088         }
1089
1090         sdata->u.ibss.skb = skb;
1091         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1092         sdata->u.ibss.ibss_join_req = jiffies;
1093
1094         memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN);
1095         sdata->u.ibss.ssid_len = params->ssid_len;
1096
1097         mutex_unlock(&sdata->u.ibss.mtx);
1098
1099         mutex_lock(&sdata->local->mtx);
1100         ieee80211_recalc_idle(sdata->local);
1101         mutex_unlock(&sdata->local->mtx);
1102
1103         /*
1104          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1105          * reserved, but an HT STA shall protect HT transmissions as though
1106          * the HT Protection field were set to non-HT mixed mode.
1107          *
1108          * In an IBSS, the RIFS Mode field of the HT Operation element is
1109          * also reserved, but an HT STA shall operate as though this field
1110          * were set to 1.
1111          */
1112
1113         sdata->vif.bss_conf.ht_operation_mode |=
1114                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1115                 | IEEE80211_HT_PARAM_RIFS_MODE;
1116
1117         changed |= BSS_CHANGED_HT;
1118         ieee80211_bss_info_change_notify(sdata, changed);
1119
1120         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1121
1122         return 0;
1123 }
1124
1125 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1126 {
1127         struct sk_buff *skb;
1128         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1129         struct ieee80211_local *local = sdata->local;
1130         struct cfg80211_bss *cbss;
1131         u16 capability;
1132         int active_ibss;
1133         struct sta_info *sta;
1134
1135         mutex_lock(&sdata->u.ibss.mtx);
1136
1137         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1138         memset(sdata->u.ibss.bssid, 0, ETH_ALEN);
1139         sdata->u.ibss.ssid_len = 0;
1140
1141         active_ibss = ieee80211_sta_active_ibss(sdata);
1142
1143         if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1144                 capability = WLAN_CAPABILITY_IBSS;
1145
1146                 if (ifibss->privacy)
1147                         capability |= WLAN_CAPABILITY_PRIVACY;
1148
1149                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel,
1150                                         ifibss->bssid, ifibss->ssid,
1151                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1152                                         WLAN_CAPABILITY_PRIVACY,
1153                                         capability);
1154
1155                 if (cbss) {
1156                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
1157                         cfg80211_put_bss(cbss);
1158                 }
1159         }
1160
1161         sta_info_flush(sdata->local, sdata);
1162
1163         spin_lock_bh(&ifibss->incomplete_lock);
1164         while (!list_empty(&ifibss->incomplete_stations)) {
1165                 sta = list_first_entry(&ifibss->incomplete_stations,
1166                                        struct sta_info, list);
1167                 list_del(&sta->list);
1168                 spin_unlock_bh(&ifibss->incomplete_lock);
1169
1170                 sta_info_free(local, sta);
1171                 spin_lock_bh(&ifibss->incomplete_lock);
1172         }
1173         spin_unlock_bh(&ifibss->incomplete_lock);
1174
1175         netif_carrier_off(sdata->dev);
1176
1177         /* remove beacon */
1178         kfree(sdata->u.ibss.ie);
1179         skb = rcu_dereference_protected(sdata->u.ibss.presp,
1180                                         lockdep_is_held(&sdata->u.ibss.mtx));
1181         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1182         sdata->vif.bss_conf.ibss_joined = false;
1183         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1184                                                 BSS_CHANGED_IBSS);
1185         synchronize_rcu();
1186         kfree_skb(skb);
1187
1188         skb_queue_purge(&sdata->skb_queue);
1189
1190         del_timer_sync(&sdata->u.ibss.timer);
1191
1192         mutex_unlock(&sdata->u.ibss.mtx);
1193
1194         mutex_lock(&local->mtx);
1195         ieee80211_recalc_idle(sdata->local);
1196         mutex_unlock(&local->mtx);
1197
1198         return 0;
1199 }