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