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