Merge commit 'c1e140bf79d817d4a7aa9932eb98b0359c87af33' from mac80211-next
[cascardo/linux.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  * Copyright 2013-2014  Intel Mobile Communications GmbH
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License version 2 as
13  * published by the Free Software Foundation.
14  */
15
16 #include <linux/delay.h>
17 #include <linux/slab.h>
18 #include <linux/if_ether.h>
19 #include <linux/skbuff.h>
20 #include <linux/if_arp.h>
21 #include <linux/etherdevice.h>
22 #include <linux/rtnetlink.h>
23 #include <net/mac80211.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_IBSS_JOIN_TIMEOUT (7 * HZ)
31
32 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
33 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
34 #define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
35
36 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
37
38 static struct beacon_data *
39 ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
40                            const int beacon_int, const u32 basic_rates,
41                            const u16 capability, u64 tsf,
42                            struct cfg80211_chan_def *chandef,
43                            bool *have_higher_than_11mbit,
44                            struct cfg80211_csa_settings *csa_settings)
45 {
46         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
47         struct ieee80211_local *local = sdata->local;
48         int rates_n = 0, i, ri;
49         struct ieee80211_mgmt *mgmt;
50         u8 *pos;
51         struct ieee80211_supported_band *sband;
52         u32 rate_flags, rates = 0, rates_added = 0;
53         struct beacon_data *presp;
54         int frame_len;
55         int shift;
56
57         /* Build IBSS probe response */
58         frame_len = sizeof(struct ieee80211_hdr_3addr) +
59                     12 /* struct ieee80211_mgmt.u.beacon */ +
60                     2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
61                     2 + 8 /* max Supported Rates */ +
62                     3 /* max DS params */ +
63                     4 /* IBSS params */ +
64                     5 /* Channel Switch Announcement */ +
65                     2 + (IEEE80211_MAX_SUPP_RATES - 8) +
66                     2 + sizeof(struct ieee80211_ht_cap) +
67                     2 + sizeof(struct ieee80211_ht_operation) +
68                     ifibss->ie_len;
69         presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
70         if (!presp)
71                 return NULL;
72
73         presp->head = (void *)(presp + 1);
74
75         mgmt = (void *) presp->head;
76         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
77                                           IEEE80211_STYPE_PROBE_RESP);
78         eth_broadcast_addr(mgmt->da);
79         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
80         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
81         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
82         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
83         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
84
85         pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
86
87         *pos++ = WLAN_EID_SSID;
88         *pos++ = ifibss->ssid_len;
89         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
90         pos += ifibss->ssid_len;
91
92         sband = local->hw.wiphy->bands[chandef->chan->band];
93         rate_flags = ieee80211_chandef_rate_flags(chandef);
94         shift = ieee80211_chandef_get_shift(chandef);
95         rates_n = 0;
96         if (have_higher_than_11mbit)
97                 *have_higher_than_11mbit = false;
98
99         for (i = 0; i < sband->n_bitrates; i++) {
100                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
101                         continue;
102                 if (sband->bitrates[i].bitrate > 110 &&
103                     have_higher_than_11mbit)
104                         *have_higher_than_11mbit = true;
105
106                 rates |= BIT(i);
107                 rates_n++;
108         }
109
110         *pos++ = WLAN_EID_SUPP_RATES;
111         *pos++ = min_t(int, 8, rates_n);
112         for (ri = 0; ri < sband->n_bitrates; ri++) {
113                 int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
114                                         5 * (1 << shift));
115                 u8 basic = 0;
116                 if (!(rates & BIT(ri)))
117                         continue;
118
119                 if (basic_rates & BIT(ri))
120                         basic = 0x80;
121                 *pos++ = basic | (u8) rate;
122                 if (++rates_added == 8) {
123                         ri++; /* continue at next rate for EXT_SUPP_RATES */
124                         break;
125                 }
126         }
127
128         if (sband->band == IEEE80211_BAND_2GHZ) {
129                 *pos++ = WLAN_EID_DS_PARAMS;
130                 *pos++ = 1;
131                 *pos++ = ieee80211_frequency_to_channel(
132                                 chandef->chan->center_freq);
133         }
134
135         *pos++ = WLAN_EID_IBSS_PARAMS;
136         *pos++ = 2;
137         /* FIX: set ATIM window based on scan results */
138         *pos++ = 0;
139         *pos++ = 0;
140
141         if (csa_settings) {
142                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
143                 *pos++ = 3;
144                 *pos++ = csa_settings->block_tx ? 1 : 0;
145                 *pos++ = ieee80211_frequency_to_channel(
146                                 csa_settings->chandef.chan->center_freq);
147                 presp->csa_counter_offsets[0] = (pos - presp->head);
148                 *pos++ = csa_settings->count;
149         }
150
151         /* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
152         if (rates_n > 8) {
153                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
154                 *pos++ = rates_n - 8;
155                 for (; ri < sband->n_bitrates; ri++) {
156                         int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
157                                                 5 * (1 << shift));
158                         u8 basic = 0;
159                         if (!(rates & BIT(ri)))
160                                 continue;
161
162                         if (basic_rates & BIT(ri))
163                                 basic = 0x80;
164                         *pos++ = basic | (u8) rate;
165                 }
166         }
167
168         if (ifibss->ie_len) {
169                 memcpy(pos, ifibss->ie, ifibss->ie_len);
170                 pos += ifibss->ie_len;
171         }
172
173         /* add HT capability and information IEs */
174         if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
175             chandef->width != NL80211_CHAN_WIDTH_5 &&
176             chandef->width != NL80211_CHAN_WIDTH_10 &&
177             sband->ht_cap.ht_supported) {
178                 struct ieee80211_sta_ht_cap ht_cap;
179
180                 memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
181                 ieee80211_apply_htcap_overrides(sdata, &ht_cap);
182
183                 pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
184                 /*
185                  * Note: According to 802.11n-2009 9.13.3.1, HT Protection
186                  * field and RIFS Mode are reserved in IBSS mode, therefore
187                  * keep them at 0
188                  */
189                 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
190                                                  chandef, 0);
191         }
192
193         if (local->hw.queues >= IEEE80211_NUM_ACS)
194                 pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
195
196         presp->head_len = pos - presp->head;
197         if (WARN_ON(presp->head_len > frame_len))
198                 goto error;
199
200         return presp;
201 error:
202         kfree(presp);
203         return NULL;
204 }
205
206 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
207                                       const u8 *bssid, const int beacon_int,
208                                       struct cfg80211_chan_def *req_chandef,
209                                       const u32 basic_rates,
210                                       const u16 capability, u64 tsf,
211                                       bool creator)
212 {
213         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
214         struct ieee80211_local *local = sdata->local;
215         struct ieee80211_mgmt *mgmt;
216         struct cfg80211_bss *bss;
217         u32 bss_change;
218         struct cfg80211_chan_def chandef;
219         struct ieee80211_channel *chan;
220         struct beacon_data *presp;
221         enum nl80211_bss_scan_width scan_width;
222         bool have_higher_than_11mbit;
223         bool radar_required;
224         int err;
225
226         sdata_assert_lock(sdata);
227
228         /* Reset own TSF to allow time synchronization work. */
229         drv_reset_tsf(local, sdata);
230
231         if (!ether_addr_equal(ifibss->bssid, bssid))
232                 sta_info_flush(sdata);
233
234         /* if merging, indicate to driver that we leave the old IBSS */
235         if (sdata->vif.bss_conf.ibss_joined) {
236                 sdata->vif.bss_conf.ibss_joined = false;
237                 sdata->vif.bss_conf.ibss_creator = false;
238                 sdata->vif.bss_conf.enable_beacon = false;
239                 netif_carrier_off(sdata->dev);
240                 ieee80211_bss_info_change_notify(sdata,
241                                                  BSS_CHANGED_IBSS |
242                                                  BSS_CHANGED_BEACON_ENABLED);
243                 drv_leave_ibss(local, sdata);
244         }
245
246         presp = rcu_dereference_protected(ifibss->presp,
247                                           lockdep_is_held(&sdata->wdev.mtx));
248         RCU_INIT_POINTER(ifibss->presp, NULL);
249         if (presp)
250                 kfree_rcu(presp, rcu_head);
251
252         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
253
254         /* make a copy of the chandef, it could be modified below. */
255         chandef = *req_chandef;
256         chan = chandef.chan;
257         if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
258                                      NL80211_IFTYPE_ADHOC)) {
259                 if (chandef.width == NL80211_CHAN_WIDTH_5 ||
260                     chandef.width == NL80211_CHAN_WIDTH_10 ||
261                     chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
262                     chandef.width == NL80211_CHAN_WIDTH_20) {
263                         sdata_info(sdata,
264                                    "Failed to join IBSS, beacons forbidden\n");
265                         return;
266                 }
267                 chandef.width = NL80211_CHAN_WIDTH_20;
268                 chandef.center_freq1 = chan->center_freq;
269                 /* check again for downgraded chandef */
270                 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
271                                              NL80211_IFTYPE_ADHOC)) {
272                         sdata_info(sdata,
273                                    "Failed to join IBSS, beacons forbidden\n");
274                         return;
275                 }
276         }
277
278         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
279                                             &chandef, NL80211_IFTYPE_ADHOC);
280         if (err < 0) {
281                 sdata_info(sdata,
282                            "Failed to join IBSS, invalid chandef\n");
283                 return;
284         }
285         if (err > 0 && !ifibss->userspace_handles_dfs) {
286                 sdata_info(sdata,
287                            "Failed to join IBSS, DFS channel without control program\n");
288                 return;
289         }
290
291         radar_required = err;
292
293         mutex_lock(&local->mtx);
294         if (ieee80211_vif_use_channel(sdata, &chandef,
295                                       ifibss->fixed_channel ?
296                                         IEEE80211_CHANCTX_SHARED :
297                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
298                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
299                 mutex_unlock(&local->mtx);
300                 return;
301         }
302         sdata->radar_required = radar_required;
303         mutex_unlock(&local->mtx);
304
305         memcpy(ifibss->bssid, bssid, ETH_ALEN);
306
307         presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
308                                            capability, tsf, &chandef,
309                                            &have_higher_than_11mbit, NULL);
310         if (!presp)
311                 return;
312
313         rcu_assign_pointer(ifibss->presp, presp);
314         mgmt = (void *)presp->head;
315
316         sdata->vif.bss_conf.enable_beacon = true;
317         sdata->vif.bss_conf.beacon_int = beacon_int;
318         sdata->vif.bss_conf.basic_rates = basic_rates;
319         sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
320         memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
321         bss_change = BSS_CHANGED_BEACON_INT;
322         bss_change |= ieee80211_reset_erp_info(sdata);
323         bss_change |= BSS_CHANGED_BSSID;
324         bss_change |= BSS_CHANGED_BEACON;
325         bss_change |= BSS_CHANGED_BEACON_ENABLED;
326         bss_change |= BSS_CHANGED_BASIC_RATES;
327         bss_change |= BSS_CHANGED_HT;
328         bss_change |= BSS_CHANGED_IBSS;
329         bss_change |= BSS_CHANGED_SSID;
330
331         /*
332          * In 5 GHz/802.11a, we can always use short slot time.
333          * (IEEE 802.11-2012 18.3.8.7)
334          *
335          * In 2.4GHz, we must always use long slots in IBSS for compatibility
336          * reasons.
337          * (IEEE 802.11-2012 19.4.5)
338          *
339          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
340          */
341         sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
342         bss_change |= BSS_CHANGED_ERP_SLOT;
343
344         /* cf. IEEE 802.11 9.2.12 */
345         if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit)
346                 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
347         else
348                 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
349
350         ieee80211_set_wmm_default(sdata, true);
351
352         sdata->vif.bss_conf.ibss_joined = true;
353         sdata->vif.bss_conf.ibss_creator = creator;
354
355         err = drv_join_ibss(local, sdata);
356         if (err) {
357                 sdata->vif.bss_conf.ibss_joined = false;
358                 sdata->vif.bss_conf.ibss_creator = false;
359                 sdata->vif.bss_conf.enable_beacon = false;
360                 sdata->vif.bss_conf.ssid_len = 0;
361                 RCU_INIT_POINTER(ifibss->presp, NULL);
362                 kfree_rcu(presp, rcu_head);
363                 mutex_lock(&local->mtx);
364                 ieee80211_vif_release_channel(sdata);
365                 mutex_unlock(&local->mtx);
366                 sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
367                            err);
368                 return;
369         }
370
371         ieee80211_bss_info_change_notify(sdata, bss_change);
372
373         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
374         mod_timer(&ifibss->timer,
375                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
376
377         scan_width = cfg80211_chandef_to_scan_width(&chandef);
378         bss = cfg80211_inform_bss_width_frame(local->hw.wiphy, chan,
379                                               scan_width, mgmt,
380                                               presp->head_len, 0, GFP_KERNEL);
381         cfg80211_put_bss(local->hw.wiphy, bss);
382         netif_carrier_on(sdata->dev);
383         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
384 }
385
386 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
387                                     struct ieee80211_bss *bss)
388 {
389         struct cfg80211_bss *cbss =
390                 container_of((void *)bss, struct cfg80211_bss, priv);
391         struct ieee80211_supported_band *sband;
392         struct cfg80211_chan_def chandef;
393         u32 basic_rates;
394         int i, j;
395         u16 beacon_int = cbss->beacon_interval;
396         const struct cfg80211_bss_ies *ies;
397         enum nl80211_channel_type chan_type;
398         u64 tsf;
399         u32 rate_flags;
400         int shift;
401
402         sdata_assert_lock(sdata);
403
404         if (beacon_int < 10)
405                 beacon_int = 10;
406
407         switch (sdata->u.ibss.chandef.width) {
408         case NL80211_CHAN_WIDTH_20_NOHT:
409         case NL80211_CHAN_WIDTH_20:
410         case NL80211_CHAN_WIDTH_40:
411                 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
412                 cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
413                 break;
414         case NL80211_CHAN_WIDTH_5:
415         case NL80211_CHAN_WIDTH_10:
416                 cfg80211_chandef_create(&chandef, cbss->channel,
417                                         NL80211_CHAN_WIDTH_20_NOHT);
418                 chandef.width = sdata->u.ibss.chandef.width;
419                 break;
420         default:
421                 /* fall back to 20 MHz for unsupported modes */
422                 cfg80211_chandef_create(&chandef, cbss->channel,
423                                         NL80211_CHAN_WIDTH_20_NOHT);
424                 break;
425         }
426
427         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
428         rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
429         shift = ieee80211_vif_get_shift(&sdata->vif);
430
431         basic_rates = 0;
432
433         for (i = 0; i < bss->supp_rates_len; i++) {
434                 int rate = bss->supp_rates[i] & 0x7f;
435                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
436
437                 for (j = 0; j < sband->n_bitrates; j++) {
438                         int brate;
439                         if ((rate_flags & sband->bitrates[j].flags)
440                             != rate_flags)
441                                 continue;
442
443                         brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
444                                              5 * (1 << shift));
445                         if (brate == rate) {
446                                 if (is_basic)
447                                         basic_rates |= BIT(j);
448                                 break;
449                         }
450                 }
451         }
452
453         rcu_read_lock();
454         ies = rcu_dereference(cbss->ies);
455         tsf = ies->tsf;
456         rcu_read_unlock();
457
458         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
459                                   beacon_int,
460                                   &chandef,
461                                   basic_rates,
462                                   cbss->capability,
463                                   tsf, false);
464 }
465
466 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
467                               struct cfg80211_csa_settings *csa_settings)
468 {
469         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
470         struct beacon_data *presp, *old_presp;
471         struct cfg80211_bss *cbss;
472         const struct cfg80211_bss_ies *ies;
473         u16 capability;
474         u64 tsf;
475         int ret = 0;
476
477         sdata_assert_lock(sdata);
478
479         capability = WLAN_CAPABILITY_IBSS;
480
481         if (ifibss->privacy)
482                 capability |= WLAN_CAPABILITY_PRIVACY;
483
484         cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
485                                 ifibss->bssid, ifibss->ssid,
486                                 ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
487                                 WLAN_CAPABILITY_PRIVACY,
488                                 capability);
489
490         if (WARN_ON(!cbss)) {
491                 ret = -EINVAL;
492                 goto out;
493         }
494
495         rcu_read_lock();
496         ies = rcu_dereference(cbss->ies);
497         tsf = ies->tsf;
498         rcu_read_unlock();
499         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
500
501         old_presp = rcu_dereference_protected(ifibss->presp,
502                                           lockdep_is_held(&sdata->wdev.mtx));
503
504         presp = ieee80211_ibss_build_presp(sdata,
505                                            sdata->vif.bss_conf.beacon_int,
506                                            sdata->vif.bss_conf.basic_rates,
507                                            capability, tsf, &ifibss->chandef,
508                                            NULL, csa_settings);
509         if (!presp) {
510                 ret = -ENOMEM;
511                 goto out;
512         }
513
514         rcu_assign_pointer(ifibss->presp, presp);
515         if (old_presp)
516                 kfree_rcu(old_presp, rcu_head);
517
518         return BSS_CHANGED_BEACON;
519  out:
520         return ret;
521 }
522
523 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
524 {
525         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
526         struct cfg80211_bss *cbss;
527         int err, changed = 0;
528         u16 capability;
529
530         sdata_assert_lock(sdata);
531
532         /* update cfg80211 bss information with the new channel */
533         if (!is_zero_ether_addr(ifibss->bssid)) {
534                 capability = WLAN_CAPABILITY_IBSS;
535
536                 if (ifibss->privacy)
537                         capability |= WLAN_CAPABILITY_PRIVACY;
538
539                 cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
540                                         ifibss->chandef.chan,
541                                         ifibss->bssid, ifibss->ssid,
542                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
543                                         WLAN_CAPABILITY_PRIVACY,
544                                         capability);
545                 /* XXX: should not really modify cfg80211 data */
546                 if (cbss) {
547                         cbss->channel = sdata->csa_chandef.chan;
548                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
549                 }
550         }
551
552         ifibss->chandef = sdata->csa_chandef;
553
554         /* generate the beacon */
555         err = ieee80211_ibss_csa_beacon(sdata, NULL);
556         if (err < 0)
557                 return err;
558
559         changed |= err;
560
561         return changed;
562 }
563
564 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
565 {
566         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
567
568         cancel_work_sync(&ifibss->csa_connection_drop_work);
569 }
570
571 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
572         __acquires(RCU)
573 {
574         struct ieee80211_sub_if_data *sdata = sta->sdata;
575         u8 addr[ETH_ALEN];
576
577         memcpy(addr, sta->sta.addr, ETH_ALEN);
578
579         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
580
581         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
582         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
583         /* authorize the station only if the network is not RSN protected. If
584          * not wait for the userspace to authorize it */
585         if (!sta->sdata->u.ibss.control_port)
586                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
587
588         rate_control_rate_init(sta);
589
590         /* If it fails, maybe we raced another insertion? */
591         if (sta_info_insert_rcu(sta))
592                 return sta_info_get(sdata, addr);
593         return sta;
594 }
595
596 static struct sta_info *
597 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
598                        const u8 *addr, u32 supp_rates)
599         __acquires(RCU)
600 {
601         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
602         struct ieee80211_local *local = sdata->local;
603         struct sta_info *sta;
604         struct ieee80211_chanctx_conf *chanctx_conf;
605         struct ieee80211_supported_band *sband;
606         enum nl80211_bss_scan_width scan_width;
607         int band;
608
609         /*
610          * XXX: Consider removing the least recently used entry and
611          *      allow new one to be added.
612          */
613         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
614                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
615                                     sdata->name, addr);
616                 rcu_read_lock();
617                 return NULL;
618         }
619
620         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
621                 rcu_read_lock();
622                 return NULL;
623         }
624
625         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
626                 rcu_read_lock();
627                 return NULL;
628         }
629
630         rcu_read_lock();
631         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
632         if (WARN_ON_ONCE(!chanctx_conf))
633                 return NULL;
634         band = chanctx_conf->def.chan->band;
635         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
636         rcu_read_unlock();
637
638         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
639         if (!sta) {
640                 rcu_read_lock();
641                 return NULL;
642         }
643
644         sta->last_rx = jiffies;
645
646         /* make sure mandatory rates are always added */
647         sband = local->hw.wiphy->bands[band];
648         sta->sta.supp_rates[band] = supp_rates |
649                         ieee80211_mandatory_rates(sband, scan_width);
650
651         return ieee80211_ibss_finish_sta(sta);
652 }
653
654 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
655 {
656         struct ieee80211_local *local = sdata->local;
657         int active = 0;
658         struct sta_info *sta;
659
660         sdata_assert_lock(sdata);
661
662         rcu_read_lock();
663
664         list_for_each_entry_rcu(sta, &local->sta_list, list) {
665                 if (sta->sdata == sdata &&
666                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
667                                jiffies)) {
668                         active++;
669                         break;
670                 }
671         }
672
673         rcu_read_unlock();
674
675         return active;
676 }
677
678 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
679 {
680         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
681         struct ieee80211_local *local = sdata->local;
682         struct cfg80211_bss *cbss;
683         struct beacon_data *presp;
684         struct sta_info *sta;
685         u16 capability;
686
687         if (!is_zero_ether_addr(ifibss->bssid)) {
688                 capability = WLAN_CAPABILITY_IBSS;
689
690                 if (ifibss->privacy)
691                         capability |= WLAN_CAPABILITY_PRIVACY;
692
693                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
694                                         ifibss->bssid, ifibss->ssid,
695                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
696                                         WLAN_CAPABILITY_PRIVACY,
697                                         capability);
698
699                 if (cbss) {
700                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
701                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
702                 }
703         }
704
705         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
706
707         sta_info_flush(sdata);
708
709         spin_lock_bh(&ifibss->incomplete_lock);
710         while (!list_empty(&ifibss->incomplete_stations)) {
711                 sta = list_first_entry(&ifibss->incomplete_stations,
712                                        struct sta_info, list);
713                 list_del(&sta->list);
714                 spin_unlock_bh(&ifibss->incomplete_lock);
715
716                 sta_info_free(local, sta);
717                 spin_lock_bh(&ifibss->incomplete_lock);
718         }
719         spin_unlock_bh(&ifibss->incomplete_lock);
720
721         netif_carrier_off(sdata->dev);
722
723         sdata->vif.bss_conf.ibss_joined = false;
724         sdata->vif.bss_conf.ibss_creator = false;
725         sdata->vif.bss_conf.enable_beacon = false;
726         sdata->vif.bss_conf.ssid_len = 0;
727
728         /* remove beacon */
729         presp = rcu_dereference_protected(ifibss->presp,
730                                           lockdep_is_held(&sdata->wdev.mtx));
731         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
732         if (presp)
733                 kfree_rcu(presp, rcu_head);
734
735         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
736         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
737                                                 BSS_CHANGED_IBSS);
738         drv_leave_ibss(local, sdata);
739         mutex_lock(&local->mtx);
740         ieee80211_vif_release_channel(sdata);
741         mutex_unlock(&local->mtx);
742 }
743
744 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
745 {
746         struct ieee80211_sub_if_data *sdata =
747                 container_of(work, struct ieee80211_sub_if_data,
748                              u.ibss.csa_connection_drop_work);
749
750         sdata_lock(sdata);
751
752         ieee80211_ibss_disconnect(sdata);
753         synchronize_rcu();
754         skb_queue_purge(&sdata->skb_queue);
755
756         /* trigger a scan to find another IBSS network to join */
757         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
758
759         sdata_unlock(sdata);
760 }
761
762 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
763 {
764         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
765         int err;
766
767         /* if the current channel is a DFS channel, mark the channel as
768          * unavailable.
769          */
770         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
771                                             &ifibss->chandef,
772                                             NL80211_IFTYPE_ADHOC);
773         if (err > 0)
774                 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
775                                      GFP_ATOMIC);
776 }
777
778 static bool
779 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
780                                   struct ieee802_11_elems *elems,
781                                   bool beacon)
782 {
783         struct cfg80211_csa_settings params;
784         struct ieee80211_csa_ie csa_ie;
785         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
786         enum nl80211_channel_type ch_type;
787         int err;
788         u32 sta_flags;
789
790         sdata_assert_lock(sdata);
791
792         sta_flags = IEEE80211_STA_DISABLE_VHT;
793         switch (ifibss->chandef.width) {
794         case NL80211_CHAN_WIDTH_5:
795         case NL80211_CHAN_WIDTH_10:
796         case NL80211_CHAN_WIDTH_20_NOHT:
797                 sta_flags |= IEEE80211_STA_DISABLE_HT;
798                 /* fall through */
799         case NL80211_CHAN_WIDTH_20:
800                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
801                 break;
802         default:
803                 break;
804         }
805
806         memset(&params, 0, sizeof(params));
807         memset(&csa_ie, 0, sizeof(csa_ie));
808         err = ieee80211_parse_ch_switch_ie(sdata, elems,
809                                            ifibss->chandef.chan->band,
810                                            sta_flags, ifibss->bssid, &csa_ie);
811         /* can't switch to destination channel, fail */
812         if (err < 0)
813                 goto disconnect;
814
815         /* did not contain a CSA */
816         if (err)
817                 return false;
818
819         /* channel switch is not supported, disconnect */
820         if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
821                 goto disconnect;
822
823         params.count = csa_ie.count;
824         params.chandef = csa_ie.chandef;
825
826         switch (ifibss->chandef.width) {
827         case NL80211_CHAN_WIDTH_20_NOHT:
828         case NL80211_CHAN_WIDTH_20:
829         case NL80211_CHAN_WIDTH_40:
830                 /* keep our current HT mode (HT20/HT40+/HT40-), even if
831                  * another mode  has been announced. The mode is not adopted
832                  * within the beacon while doing CSA and we should therefore
833                  * keep the mode which we announce.
834                  */
835                 ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
836                 cfg80211_chandef_create(&params.chandef, params.chandef.chan,
837                                         ch_type);
838                 break;
839         case NL80211_CHAN_WIDTH_5:
840         case NL80211_CHAN_WIDTH_10:
841                 if (params.chandef.width != ifibss->chandef.width) {
842                         sdata_info(sdata,
843                                    "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
844                                    ifibss->bssid,
845                                    params.chandef.chan->center_freq,
846                                    params.chandef.width,
847                                    params.chandef.center_freq1,
848                                    params.chandef.center_freq2);
849                         goto disconnect;
850                 }
851                 break;
852         default:
853                 /* should not happen, sta_flags should prevent VHT modes. */
854                 WARN_ON(1);
855                 goto disconnect;
856         }
857
858         if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
859                                      NL80211_IFTYPE_ADHOC)) {
860                 sdata_info(sdata,
861                            "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
862                            ifibss->bssid,
863                            params.chandef.chan->center_freq,
864                            params.chandef.width,
865                            params.chandef.center_freq1,
866                            params.chandef.center_freq2);
867                 goto disconnect;
868         }
869
870         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
871                                             &params.chandef,
872                                             NL80211_IFTYPE_ADHOC);
873         if (err < 0)
874                 goto disconnect;
875         if (err > 0 && !ifibss->userspace_handles_dfs) {
876                 /* IBSS-DFS only allowed with a control program */
877                 goto disconnect;
878         }
879
880         params.radar_required = err;
881
882         if (cfg80211_chandef_identical(&params.chandef,
883                                        &sdata->vif.bss_conf.chandef)) {
884                 ibss_dbg(sdata,
885                          "received csa with an identical chandef, ignoring\n");
886                 return true;
887         }
888
889         /* all checks done, now perform the channel switch. */
890         ibss_dbg(sdata,
891                  "received channel switch announcement to go to channel %d MHz\n",
892                  params.chandef.chan->center_freq);
893
894         params.block_tx = !!csa_ie.mode;
895
896         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
897                                      &params))
898                 goto disconnect;
899
900         ieee80211_ibss_csa_mark_radar(sdata);
901
902         return true;
903 disconnect:
904         ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
905         ieee80211_queue_work(&sdata->local->hw,
906                              &ifibss->csa_connection_drop_work);
907
908         ieee80211_ibss_csa_mark_radar(sdata);
909
910         return true;
911 }
912
913 static void
914 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
915                                 struct ieee80211_mgmt *mgmt, size_t len,
916                                 struct ieee80211_rx_status *rx_status,
917                                 struct ieee802_11_elems *elems)
918 {
919         int required_len;
920
921         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
922                 return;
923
924         /* CSA is the only action we handle for now */
925         if (mgmt->u.action.u.measurement.action_code !=
926             WLAN_ACTION_SPCT_CHL_SWITCH)
927                 return;
928
929         required_len = IEEE80211_MIN_ACTION_SIZE +
930                        sizeof(mgmt->u.action.u.chan_switch);
931         if (len < required_len)
932                 return;
933
934         if (!sdata->vif.csa_active)
935                 ieee80211_ibss_process_chanswitch(sdata, elems, false);
936 }
937
938 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
939                                           struct ieee80211_mgmt *mgmt,
940                                           size_t len)
941 {
942         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
943
944         if (len < IEEE80211_DEAUTH_FRAME_LEN)
945                 return;
946
947         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
948                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
949         sta_info_destroy_addr(sdata, mgmt->sa);
950 }
951
952 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
953                                         struct ieee80211_mgmt *mgmt,
954                                         size_t len)
955 {
956         u16 auth_alg, auth_transaction;
957
958         sdata_assert_lock(sdata);
959
960         if (len < 24 + 6)
961                 return;
962
963         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
964         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
965
966         ibss_dbg(sdata,
967                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
968                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
969
970         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
971                 return;
972
973         /*
974          * IEEE 802.11 standard does not require authentication in IBSS
975          * networks and most implementations do not seem to use it.
976          * However, try to reply to authentication attempts if someone
977          * has actually implemented this.
978          */
979         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
980                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
981 }
982
983 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
984                                   struct ieee80211_mgmt *mgmt, size_t len,
985                                   struct ieee80211_rx_status *rx_status,
986                                   struct ieee802_11_elems *elems)
987 {
988         struct ieee80211_local *local = sdata->local;
989         struct cfg80211_bss *cbss;
990         struct ieee80211_bss *bss;
991         struct sta_info *sta;
992         struct ieee80211_channel *channel;
993         u64 beacon_timestamp, rx_timestamp;
994         u32 supp_rates = 0;
995         enum ieee80211_band band = rx_status->band;
996         enum nl80211_bss_scan_width scan_width;
997         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
998         bool rates_updated = false;
999
1000         channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1001         if (!channel)
1002                 return;
1003
1004         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
1005             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
1006
1007                 rcu_read_lock();
1008                 sta = sta_info_get(sdata, mgmt->sa);
1009
1010                 if (elems->supp_rates) {
1011                         supp_rates = ieee80211_sta_get_rates(sdata, elems,
1012                                                              band, NULL);
1013                         if (sta) {
1014                                 u32 prev_rates;
1015
1016                                 prev_rates = sta->sta.supp_rates[band];
1017                                 /* make sure mandatory rates are always added */
1018                                 scan_width = NL80211_BSS_CHAN_WIDTH_20;
1019                                 if (rx_status->flag & RX_FLAG_5MHZ)
1020                                         scan_width = NL80211_BSS_CHAN_WIDTH_5;
1021                                 if (rx_status->flag & RX_FLAG_10MHZ)
1022                                         scan_width = NL80211_BSS_CHAN_WIDTH_10;
1023
1024                                 sta->sta.supp_rates[band] = supp_rates |
1025                                         ieee80211_mandatory_rates(sband,
1026                                                                   scan_width);
1027                                 if (sta->sta.supp_rates[band] != prev_rates) {
1028                                         ibss_dbg(sdata,
1029                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1030                                                  sta->sta.addr, prev_rates,
1031                                                  sta->sta.supp_rates[band]);
1032                                         rates_updated = true;
1033                                 }
1034                         } else {
1035                                 rcu_read_unlock();
1036                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1037                                                 mgmt->sa, supp_rates);
1038                         }
1039                 }
1040
1041                 if (sta && elems->wmm_info)
1042                         sta->sta.wme = true;
1043
1044                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
1045                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1046                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1047                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1048                         /* we both use HT */
1049                         struct ieee80211_ht_cap htcap_ie;
1050                         struct cfg80211_chan_def chandef;
1051
1052                         ieee80211_ht_oper_to_chandef(channel,
1053                                                      elems->ht_operation,
1054                                                      &chandef);
1055
1056                         memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1057
1058                         /*
1059                          * fall back to HT20 if we don't use or use
1060                          * the other extension channel
1061                          */
1062                         if (chandef.center_freq1 !=
1063                             sdata->u.ibss.chandef.center_freq1)
1064                                 htcap_ie.cap_info &=
1065                                         cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
1066
1067                         rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(
1068                                                 sdata, sband, &htcap_ie, sta);
1069                 }
1070
1071                 if (sta && rates_updated) {
1072                         u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
1073                         u8 rx_nss = sta->sta.rx_nss;
1074
1075                         /* Force rx_nss recalculation */
1076                         sta->sta.rx_nss = 0;
1077                         rate_control_rate_init(sta);
1078                         if (sta->sta.rx_nss != rx_nss)
1079                                 changed |= IEEE80211_RC_NSS_CHANGED;
1080
1081                         drv_sta_rc_update(local, sdata, &sta->sta, changed);
1082                 }
1083
1084                 rcu_read_unlock();
1085         }
1086
1087         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1088                                         channel);
1089         if (!bss)
1090                 return;
1091
1092         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1093
1094         /* same for beacon and probe response */
1095         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1096
1097         /* check if we need to merge IBSS */
1098
1099         /* not an IBSS */
1100         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1101                 goto put_bss;
1102
1103         /* different channel */
1104         if (sdata->u.ibss.fixed_channel &&
1105             sdata->u.ibss.chandef.chan != cbss->channel)
1106                 goto put_bss;
1107
1108         /* different SSID */
1109         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1110             memcmp(elems->ssid, sdata->u.ibss.ssid,
1111                                 sdata->u.ibss.ssid_len))
1112                 goto put_bss;
1113
1114         /* process channel switch */
1115         if (sdata->vif.csa_active ||
1116             ieee80211_ibss_process_chanswitch(sdata, elems, true))
1117                 goto put_bss;
1118
1119         /* same BSSID */
1120         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1121                 goto put_bss;
1122
1123         /* we use a fixed BSSID */
1124         if (sdata->u.ibss.fixed_bssid)
1125                 goto put_bss;
1126
1127         if (ieee80211_have_rx_timestamp(rx_status)) {
1128                 /* time when timestamp field was received */
1129                 rx_timestamp =
1130                         ieee80211_calculate_rx_timestamp(local, rx_status,
1131                                                          len + FCS_LEN, 24);
1132         } else {
1133                 /*
1134                  * second best option: get current TSF
1135                  * (will return -1 if not supported)
1136                  */
1137                 rx_timestamp = drv_get_tsf(local, sdata);
1138         }
1139
1140         ibss_dbg(sdata,
1141                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1142                  mgmt->sa, mgmt->bssid,
1143                  (unsigned long long)rx_timestamp,
1144                  (unsigned long long)beacon_timestamp,
1145                  (unsigned long long)(rx_timestamp - beacon_timestamp),
1146                  jiffies);
1147
1148         if (beacon_timestamp > rx_timestamp) {
1149                 ibss_dbg(sdata,
1150                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1151                          mgmt->bssid);
1152                 ieee80211_sta_join_ibss(sdata, bss);
1153                 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1154                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1155                                        supp_rates);
1156                 rcu_read_unlock();
1157         }
1158
1159  put_bss:
1160         ieee80211_rx_bss_put(local, bss);
1161 }
1162
1163 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1164                               const u8 *bssid, const u8 *addr,
1165                               u32 supp_rates)
1166 {
1167         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1168         struct ieee80211_local *local = sdata->local;
1169         struct sta_info *sta;
1170         struct ieee80211_chanctx_conf *chanctx_conf;
1171         struct ieee80211_supported_band *sband;
1172         enum nl80211_bss_scan_width scan_width;
1173         int band;
1174
1175         /*
1176          * XXX: Consider removing the least recently used entry and
1177          *      allow new one to be added.
1178          */
1179         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1180                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1181                                     sdata->name, addr);
1182                 return;
1183         }
1184
1185         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1186                 return;
1187
1188         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1189                 return;
1190
1191         rcu_read_lock();
1192         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1193         if (WARN_ON_ONCE(!chanctx_conf)) {
1194                 rcu_read_unlock();
1195                 return;
1196         }
1197         band = chanctx_conf->def.chan->band;
1198         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1199         rcu_read_unlock();
1200
1201         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1202         if (!sta)
1203                 return;
1204
1205         sta->last_rx = jiffies;
1206
1207         /* make sure mandatory rates are always added */
1208         sband = local->hw.wiphy->bands[band];
1209         sta->sta.supp_rates[band] = supp_rates |
1210                         ieee80211_mandatory_rates(sband, scan_width);
1211
1212         spin_lock(&ifibss->incomplete_lock);
1213         list_add(&sta->list, &ifibss->incomplete_stations);
1214         spin_unlock(&ifibss->incomplete_lock);
1215         ieee80211_queue_work(&local->hw, &sdata->work);
1216 }
1217
1218 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1219 {
1220         struct ieee80211_local *local = sdata->local;
1221         struct sta_info *sta, *tmp;
1222         unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1223         unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1224
1225         mutex_lock(&local->sta_mtx);
1226
1227         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1228                 if (sdata != sta->sdata)
1229                         continue;
1230
1231                 if (time_after(jiffies, sta->last_rx + exp_time) ||
1232                     (time_after(jiffies, sta->last_rx + exp_rsn_time) &&
1233                      sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1234                         sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1235                                 sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1236                                 "not authorized " : "", sta->sta.addr);
1237
1238                         WARN_ON(__sta_info_destroy(sta));
1239                 }
1240         }
1241
1242         mutex_unlock(&local->sta_mtx);
1243 }
1244
1245 /*
1246  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1247  */
1248
1249 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1250 {
1251         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1252         enum nl80211_bss_scan_width scan_width;
1253
1254         sdata_assert_lock(sdata);
1255
1256         mod_timer(&ifibss->timer,
1257                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1258
1259         ieee80211_ibss_sta_expire(sdata);
1260
1261         if (time_before(jiffies, ifibss->last_scan_completed +
1262                        IEEE80211_IBSS_MERGE_INTERVAL))
1263                 return;
1264
1265         if (ieee80211_sta_active_ibss(sdata))
1266                 return;
1267
1268         if (ifibss->fixed_channel)
1269                 return;
1270
1271         sdata_info(sdata,
1272                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1273
1274         scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1275         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1276                                     NULL, scan_width);
1277 }
1278
1279 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1280 {
1281         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1282         u8 bssid[ETH_ALEN];
1283         u16 capability;
1284         int i;
1285
1286         sdata_assert_lock(sdata);
1287
1288         if (ifibss->fixed_bssid) {
1289                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
1290         } else {
1291                 /* Generate random, not broadcast, locally administered BSSID. Mix in
1292                  * own MAC address to make sure that devices that do not have proper
1293                  * random number generator get different BSSID. */
1294                 get_random_bytes(bssid, ETH_ALEN);
1295                 for (i = 0; i < ETH_ALEN; i++)
1296                         bssid[i] ^= sdata->vif.addr[i];
1297                 bssid[0] &= ~0x01;
1298                 bssid[0] |= 0x02;
1299         }
1300
1301         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1302
1303         capability = WLAN_CAPABILITY_IBSS;
1304
1305         if (ifibss->privacy)
1306                 capability |= WLAN_CAPABILITY_PRIVACY;
1307         else
1308                 sdata->drop_unencrypted = 0;
1309
1310         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1311                                   &ifibss->chandef, ifibss->basic_rates,
1312                                   capability, 0, true);
1313 }
1314
1315 /*
1316  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1317  */
1318
1319 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1320 {
1321         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1322         struct ieee80211_local *local = sdata->local;
1323         struct cfg80211_bss *cbss;
1324         struct ieee80211_channel *chan = NULL;
1325         const u8 *bssid = NULL;
1326         enum nl80211_bss_scan_width scan_width;
1327         int active_ibss;
1328         u16 capability;
1329
1330         sdata_assert_lock(sdata);
1331
1332         active_ibss = ieee80211_sta_active_ibss(sdata);
1333         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1334
1335         if (active_ibss)
1336                 return;
1337
1338         capability = WLAN_CAPABILITY_IBSS;
1339         if (ifibss->privacy)
1340                 capability |= WLAN_CAPABILITY_PRIVACY;
1341         if (ifibss->fixed_bssid)
1342                 bssid = ifibss->bssid;
1343         if (ifibss->fixed_channel)
1344                 chan = ifibss->chandef.chan;
1345         if (!is_zero_ether_addr(ifibss->bssid))
1346                 bssid = ifibss->bssid;
1347         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1348                                 ifibss->ssid, ifibss->ssid_len,
1349                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
1350                                 capability);
1351
1352         if (cbss) {
1353                 struct ieee80211_bss *bss;
1354
1355                 bss = (void *)cbss->priv;
1356                 ibss_dbg(sdata,
1357                          "sta_find_ibss: selected %pM current %pM\n",
1358                          cbss->bssid, ifibss->bssid);
1359                 sdata_info(sdata,
1360                            "Selected IBSS BSSID %pM based on configured SSID\n",
1361                            cbss->bssid);
1362
1363                 ieee80211_sta_join_ibss(sdata, bss);
1364                 ieee80211_rx_bss_put(local, bss);
1365                 return;
1366         }
1367
1368         /* if a fixed bssid and a fixed freq have been provided create the IBSS
1369          * directly and do not waste time scanning
1370          */
1371         if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1372                 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1373                            bssid);
1374                 ieee80211_sta_create_ibss(sdata);
1375                 return;
1376         }
1377
1378
1379         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1380
1381         /* Selected IBSS not found in current scan results - try to scan */
1382         if (time_after(jiffies, ifibss->last_scan_completed +
1383                                         IEEE80211_SCAN_INTERVAL)) {
1384                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1385
1386                 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1387                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1388                                             ifibss->ssid_len, chan,
1389                                             scan_width);
1390         } else {
1391                 int interval = IEEE80211_SCAN_INTERVAL;
1392
1393                 if (time_after(jiffies, ifibss->ibss_join_req +
1394                                IEEE80211_IBSS_JOIN_TIMEOUT))
1395                         ieee80211_sta_create_ibss(sdata);
1396
1397                 mod_timer(&ifibss->timer,
1398                           round_jiffies(jiffies + interval));
1399         }
1400 }
1401
1402 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1403                                         struct sk_buff *req)
1404 {
1405         struct ieee80211_mgmt *mgmt = (void *)req->data;
1406         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1407         struct ieee80211_local *local = sdata->local;
1408         int tx_last_beacon, len = req->len;
1409         struct sk_buff *skb;
1410         struct beacon_data *presp;
1411         u8 *pos, *end;
1412
1413         sdata_assert_lock(sdata);
1414
1415         presp = rcu_dereference_protected(ifibss->presp,
1416                                           lockdep_is_held(&sdata->wdev.mtx));
1417
1418         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1419             len < 24 + 2 || !presp)
1420                 return;
1421
1422         tx_last_beacon = drv_tx_last_beacon(local);
1423
1424         ibss_dbg(sdata,
1425                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1426                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1427
1428         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1429                 return;
1430
1431         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1432             !is_broadcast_ether_addr(mgmt->bssid))
1433                 return;
1434
1435         end = ((u8 *) mgmt) + len;
1436         pos = mgmt->u.probe_req.variable;
1437         if (pos[0] != WLAN_EID_SSID ||
1438             pos + 2 + pos[1] > end) {
1439                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1440                          mgmt->sa);
1441                 return;
1442         }
1443         if (pos[1] != 0 &&
1444             (pos[1] != ifibss->ssid_len ||
1445              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1446                 /* Ignore ProbeReq for foreign SSID */
1447                 return;
1448         }
1449
1450         /* Reply with ProbeResp */
1451         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1452         if (!skb)
1453                 return;
1454
1455         skb_reserve(skb, local->tx_headroom);
1456         memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1457
1458         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1459         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1460         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1461
1462         /* avoid excessive retries for probe request to wildcard SSIDs */
1463         if (pos[1] == 0)
1464                 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1465
1466         ieee80211_tx_skb(sdata, skb);
1467 }
1468
1469 static
1470 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1471                                     struct ieee80211_mgmt *mgmt, size_t len,
1472                                     struct ieee80211_rx_status *rx_status)
1473 {
1474         size_t baselen;
1475         struct ieee802_11_elems elems;
1476
1477         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1478                      offsetof(typeof(mgmt->u.beacon), variable));
1479
1480         /*
1481          * either beacon or probe_resp but the variable field is at the
1482          * same offset
1483          */
1484         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1485         if (baselen > len)
1486                 return;
1487
1488         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1489                                false, &elems);
1490
1491         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1492 }
1493
1494 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1495                                    struct sk_buff *skb)
1496 {
1497         struct ieee80211_rx_status *rx_status;
1498         struct ieee80211_mgmt *mgmt;
1499         u16 fc;
1500         struct ieee802_11_elems elems;
1501         int ies_len;
1502
1503         rx_status = IEEE80211_SKB_RXCB(skb);
1504         mgmt = (struct ieee80211_mgmt *) skb->data;
1505         fc = le16_to_cpu(mgmt->frame_control);
1506
1507         sdata_lock(sdata);
1508
1509         if (!sdata->u.ibss.ssid_len)
1510                 goto mgmt_out; /* not ready to merge yet */
1511
1512         switch (fc & IEEE80211_FCTL_STYPE) {
1513         case IEEE80211_STYPE_PROBE_REQ:
1514                 ieee80211_rx_mgmt_probe_req(sdata, skb);
1515                 break;
1516         case IEEE80211_STYPE_PROBE_RESP:
1517         case IEEE80211_STYPE_BEACON:
1518                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1519                                                rx_status);
1520                 break;
1521         case IEEE80211_STYPE_AUTH:
1522                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1523                 break;
1524         case IEEE80211_STYPE_DEAUTH:
1525                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1526                 break;
1527         case IEEE80211_STYPE_ACTION:
1528                 switch (mgmt->u.action.category) {
1529                 case WLAN_CATEGORY_SPECTRUM_MGMT:
1530                         ies_len = skb->len -
1531                                   offsetof(struct ieee80211_mgmt,
1532                                            u.action.u.chan_switch.variable);
1533
1534                         if (ies_len < 0)
1535                                 break;
1536
1537                         ieee802_11_parse_elems(
1538                                 mgmt->u.action.u.chan_switch.variable,
1539                                 ies_len, true, &elems);
1540
1541                         if (elems.parse_error)
1542                                 break;
1543
1544                         ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1545                                                         rx_status, &elems);
1546                         break;
1547                 }
1548         }
1549
1550  mgmt_out:
1551         sdata_unlock(sdata);
1552 }
1553
1554 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1555 {
1556         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1557         struct sta_info *sta;
1558
1559         sdata_lock(sdata);
1560
1561         /*
1562          * Work could be scheduled after scan or similar
1563          * when we aren't even joined (or trying) with a
1564          * network.
1565          */
1566         if (!ifibss->ssid_len)
1567                 goto out;
1568
1569         spin_lock_bh(&ifibss->incomplete_lock);
1570         while (!list_empty(&ifibss->incomplete_stations)) {
1571                 sta = list_first_entry(&ifibss->incomplete_stations,
1572                                        struct sta_info, list);
1573                 list_del(&sta->list);
1574                 spin_unlock_bh(&ifibss->incomplete_lock);
1575
1576                 ieee80211_ibss_finish_sta(sta);
1577                 rcu_read_unlock();
1578                 spin_lock_bh(&ifibss->incomplete_lock);
1579         }
1580         spin_unlock_bh(&ifibss->incomplete_lock);
1581
1582         switch (ifibss->state) {
1583         case IEEE80211_IBSS_MLME_SEARCH:
1584                 ieee80211_sta_find_ibss(sdata);
1585                 break;
1586         case IEEE80211_IBSS_MLME_JOINED:
1587                 ieee80211_sta_merge_ibss(sdata);
1588                 break;
1589         default:
1590                 WARN_ON(1);
1591                 break;
1592         }
1593
1594  out:
1595         sdata_unlock(sdata);
1596 }
1597
1598 static void ieee80211_ibss_timer(unsigned long data)
1599 {
1600         struct ieee80211_sub_if_data *sdata =
1601                 (struct ieee80211_sub_if_data *) data;
1602
1603         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1604 }
1605
1606 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1607 {
1608         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1609
1610         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1611                     (unsigned long) sdata);
1612         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1613         spin_lock_init(&ifibss->incomplete_lock);
1614         INIT_WORK(&ifibss->csa_connection_drop_work,
1615                   ieee80211_csa_connection_drop_work);
1616 }
1617
1618 /* scan finished notification */
1619 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1620 {
1621         struct ieee80211_sub_if_data *sdata;
1622
1623         mutex_lock(&local->iflist_mtx);
1624         list_for_each_entry(sdata, &local->interfaces, list) {
1625                 if (!ieee80211_sdata_running(sdata))
1626                         continue;
1627                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1628                         continue;
1629                 sdata->u.ibss.last_scan_completed = jiffies;
1630                 ieee80211_queue_work(&local->hw, &sdata->work);
1631         }
1632         mutex_unlock(&local->iflist_mtx);
1633 }
1634
1635 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1636                         struct cfg80211_ibss_params *params)
1637 {
1638         u32 changed = 0;
1639         u32 rate_flags;
1640         struct ieee80211_supported_band *sband;
1641         enum ieee80211_chanctx_mode chanmode;
1642         struct ieee80211_local *local = sdata->local;
1643         int radar_detect_width = 0;
1644         int i;
1645         int ret;
1646
1647         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1648                                             &params->chandef,
1649                                             sdata->wdev.iftype);
1650         if (ret < 0)
1651                 return ret;
1652
1653         if (ret > 0) {
1654                 if (!params->userspace_handles_dfs)
1655                         return -EINVAL;
1656                 radar_detect_width = BIT(params->chandef.width);
1657         }
1658
1659         chanmode = (params->channel_fixed && !ret) ?
1660                 IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1661
1662         mutex_lock(&local->chanctx_mtx);
1663         ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1664                                            radar_detect_width);
1665         mutex_unlock(&local->chanctx_mtx);
1666         if (ret < 0)
1667                 return ret;
1668
1669         if (params->bssid) {
1670                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1671                 sdata->u.ibss.fixed_bssid = true;
1672         } else
1673                 sdata->u.ibss.fixed_bssid = false;
1674
1675         sdata->u.ibss.privacy = params->privacy;
1676         sdata->u.ibss.control_port = params->control_port;
1677         sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1678         sdata->u.ibss.basic_rates = params->basic_rates;
1679         sdata->u.ibss.last_scan_completed = jiffies;
1680
1681         /* fix basic_rates if channel does not support these rates */
1682         rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1683         sband = local->hw.wiphy->bands[params->chandef.chan->band];
1684         for (i = 0; i < sband->n_bitrates; i++) {
1685                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1686                         sdata->u.ibss.basic_rates &= ~BIT(i);
1687         }
1688         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1689                sizeof(params->mcast_rate));
1690
1691         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1692
1693         sdata->u.ibss.chandef = params->chandef;
1694         sdata->u.ibss.fixed_channel = params->channel_fixed;
1695
1696         if (params->ie) {
1697                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1698                                            GFP_KERNEL);
1699                 if (sdata->u.ibss.ie)
1700                         sdata->u.ibss.ie_len = params->ie_len;
1701         }
1702
1703         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1704         sdata->u.ibss.ibss_join_req = jiffies;
1705
1706         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1707         sdata->u.ibss.ssid_len = params->ssid_len;
1708
1709         memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1710                sizeof(sdata->u.ibss.ht_capa));
1711         memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1712                sizeof(sdata->u.ibss.ht_capa_mask));
1713
1714         /*
1715          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1716          * reserved, but an HT STA shall protect HT transmissions as though
1717          * the HT Protection field were set to non-HT mixed mode.
1718          *
1719          * In an IBSS, the RIFS Mode field of the HT Operation element is
1720          * also reserved, but an HT STA shall operate as though this field
1721          * were set to 1.
1722          */
1723
1724         sdata->vif.bss_conf.ht_operation_mode |=
1725                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1726                 | IEEE80211_HT_PARAM_RIFS_MODE;
1727
1728         changed |= BSS_CHANGED_HT;
1729         ieee80211_bss_info_change_notify(sdata, changed);
1730
1731         sdata->smps_mode = IEEE80211_SMPS_OFF;
1732         sdata->needed_rx_chains = local->rx_chains;
1733
1734         ieee80211_queue_work(&local->hw, &sdata->work);
1735
1736         return 0;
1737 }
1738
1739 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1740 {
1741         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1742
1743         ieee80211_ibss_disconnect(sdata);
1744         ifibss->ssid_len = 0;
1745         memset(ifibss->bssid, 0, ETH_ALEN);
1746
1747         /* remove beacon */
1748         kfree(sdata->u.ibss.ie);
1749
1750         /* on the next join, re-program HT parameters */
1751         memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1752         memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1753
1754         synchronize_rcu();
1755
1756         skb_queue_purge(&sdata->skb_queue);
1757
1758         del_timer_sync(&sdata->u.ibss.timer);
1759
1760         return 0;
1761 }