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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  * Copyright(c) 2016 Intel Deutschland GmbH
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License version 2 as
14  * published by the Free Software Foundation.
15  */
16 
17 #include <linux/delay.h>
18 #include <linux/slab.h>
19 #include <linux/if_ether.h>
20 #include <linux/skbuff.h>
21 #include <linux/if_arp.h>
22 #include <linux/etherdevice.h>
23 #include <linux/rtnetlink.h>
24 #include <net/mac80211.h>
25 
26 #include "ieee80211_i.h"
27 #include "driver-ops.h"
28 #include "rate.h"
29 
30 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
31 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
32 
33 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
34 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
35 #define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
36 
37 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
38 
39 static struct beacon_data *
ieee80211_ibss_build_presp(struct ieee80211_sub_if_data * sdata,const int beacon_int,const u32 basic_rates,const u16 capability,u64 tsf,struct cfg80211_chan_def * chandef,bool * have_higher_than_11mbit,struct cfg80211_csa_settings * csa_settings)40 ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
41 			   const int beacon_int, const u32 basic_rates,
42 			   const u16 capability, u64 tsf,
43 			   struct cfg80211_chan_def *chandef,
44 			   bool *have_higher_than_11mbit,
45 			   struct cfg80211_csa_settings *csa_settings)
46 {
47 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
48 	struct ieee80211_local *local = sdata->local;
49 	int rates_n = 0, i, ri;
50 	struct ieee80211_mgmt *mgmt;
51 	u8 *pos;
52 	struct ieee80211_supported_band *sband;
53 	u32 rate_flags, rates = 0, rates_added = 0;
54 	struct beacon_data *presp;
55 	int frame_len;
56 	int shift;
57 
58 	/* Build IBSS probe response */
59 	frame_len = sizeof(struct ieee80211_hdr_3addr) +
60 		    12 /* struct ieee80211_mgmt.u.beacon */ +
61 		    2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
62 		    2 + 8 /* max Supported Rates */ +
63 		    3 /* max DS params */ +
64 		    4 /* IBSS params */ +
65 		    5 /* Channel Switch Announcement */ +
66 		    2 + (IEEE80211_MAX_SUPP_RATES - 8) +
67 		    2 + sizeof(struct ieee80211_ht_cap) +
68 		    2 + sizeof(struct ieee80211_ht_operation) +
69 		    2 + sizeof(struct ieee80211_vht_cap) +
70 		    2 + sizeof(struct ieee80211_vht_operation) +
71 		    ifibss->ie_len;
72 	presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
73 	if (!presp)
74 		return NULL;
75 
76 	presp->head = (void *)(presp + 1);
77 
78 	mgmt = (void *) presp->head;
79 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
80 					  IEEE80211_STYPE_PROBE_RESP);
81 	eth_broadcast_addr(mgmt->da);
82 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
83 	memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
84 	mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
85 	mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
86 	mgmt->u.beacon.capab_info = cpu_to_le16(capability);
87 
88 	pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
89 
90 	*pos++ = WLAN_EID_SSID;
91 	*pos++ = ifibss->ssid_len;
92 	memcpy(pos, ifibss->ssid, ifibss->ssid_len);
93 	pos += ifibss->ssid_len;
94 
95 	sband = local->hw.wiphy->bands[chandef->chan->band];
96 	rate_flags = ieee80211_chandef_rate_flags(chandef);
97 	shift = ieee80211_chandef_get_shift(chandef);
98 	rates_n = 0;
99 	if (have_higher_than_11mbit)
100 		*have_higher_than_11mbit = false;
101 
102 	for (i = 0; i < sband->n_bitrates; i++) {
103 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
104 			continue;
105 		if (sband->bitrates[i].bitrate > 110 &&
106 		    have_higher_than_11mbit)
107 			*have_higher_than_11mbit = true;
108 
109 		rates |= BIT(i);
110 		rates_n++;
111 	}
112 
113 	*pos++ = WLAN_EID_SUPP_RATES;
114 	*pos++ = min_t(int, 8, rates_n);
115 	for (ri = 0; ri < sband->n_bitrates; ri++) {
116 		int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
117 					5 * (1 << shift));
118 		u8 basic = 0;
119 		if (!(rates & BIT(ri)))
120 			continue;
121 
122 		if (basic_rates & BIT(ri))
123 			basic = 0x80;
124 		*pos++ = basic | (u8) rate;
125 		if (++rates_added == 8) {
126 			ri++; /* continue at next rate for EXT_SUPP_RATES */
127 			break;
128 		}
129 	}
130 
131 	if (sband->band == NL80211_BAND_2GHZ) {
132 		*pos++ = WLAN_EID_DS_PARAMS;
133 		*pos++ = 1;
134 		*pos++ = ieee80211_frequency_to_channel(
135 				chandef->chan->center_freq);
136 	}
137 
138 	*pos++ = WLAN_EID_IBSS_PARAMS;
139 	*pos++ = 2;
140 	/* FIX: set ATIM window based on scan results */
141 	*pos++ = 0;
142 	*pos++ = 0;
143 
144 	if (csa_settings) {
145 		*pos++ = WLAN_EID_CHANNEL_SWITCH;
146 		*pos++ = 3;
147 		*pos++ = csa_settings->block_tx ? 1 : 0;
148 		*pos++ = ieee80211_frequency_to_channel(
149 				csa_settings->chandef.chan->center_freq);
150 		presp->csa_counter_offsets[0] = (pos - presp->head);
151 		*pos++ = csa_settings->count;
152 		presp->csa_current_counter = csa_settings->count;
153 	}
154 
155 	/* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
156 	if (rates_n > 8) {
157 		*pos++ = WLAN_EID_EXT_SUPP_RATES;
158 		*pos++ = rates_n - 8;
159 		for (; ri < sband->n_bitrates; ri++) {
160 			int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
161 						5 * (1 << shift));
162 			u8 basic = 0;
163 			if (!(rates & BIT(ri)))
164 				continue;
165 
166 			if (basic_rates & BIT(ri))
167 				basic = 0x80;
168 			*pos++ = basic | (u8) rate;
169 		}
170 	}
171 
172 	if (ifibss->ie_len) {
173 		memcpy(pos, ifibss->ie, ifibss->ie_len);
174 		pos += ifibss->ie_len;
175 	}
176 
177 	/* add HT capability and information IEs */
178 	if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
179 	    chandef->width != NL80211_CHAN_WIDTH_5 &&
180 	    chandef->width != NL80211_CHAN_WIDTH_10 &&
181 	    sband->ht_cap.ht_supported) {
182 		struct ieee80211_sta_ht_cap ht_cap;
183 
184 		memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
185 		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
186 
187 		pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
188 		/*
189 		 * Note: According to 802.11n-2009 9.13.3.1, HT Protection
190 		 * field and RIFS Mode are reserved in IBSS mode, therefore
191 		 * keep them at 0
192 		 */
193 		pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
194 						 chandef, 0, false);
195 
196 		/* add VHT capability and information IEs */
197 		if (chandef->width != NL80211_CHAN_WIDTH_20 &&
198 		    chandef->width != NL80211_CHAN_WIDTH_40 &&
199 		    sband->vht_cap.vht_supported) {
200 			pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
201 							 sband->vht_cap.cap);
202 			pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
203 							  chandef);
204 		}
205 	}
206 
207 	if (local->hw.queues >= IEEE80211_NUM_ACS)
208 		pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
209 
210 	presp->head_len = pos - presp->head;
211 	if (WARN_ON(presp->head_len > frame_len))
212 		goto error;
213 
214 	return presp;
215 error:
216 	kfree(presp);
217 	return NULL;
218 }
219 
__ieee80211_sta_join_ibss(struct ieee80211_sub_if_data * sdata,const u8 * bssid,const int beacon_int,struct cfg80211_chan_def * req_chandef,const u32 basic_rates,const u16 capability,u64 tsf,bool creator)220 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
221 				      const u8 *bssid, const int beacon_int,
222 				      struct cfg80211_chan_def *req_chandef,
223 				      const u32 basic_rates,
224 				      const u16 capability, u64 tsf,
225 				      bool creator)
226 {
227 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
228 	struct ieee80211_local *local = sdata->local;
229 	struct ieee80211_mgmt *mgmt;
230 	struct cfg80211_bss *bss;
231 	u32 bss_change;
232 	struct cfg80211_chan_def chandef;
233 	struct ieee80211_channel *chan;
234 	struct beacon_data *presp;
235 	struct cfg80211_inform_bss bss_meta = {};
236 	bool have_higher_than_11mbit;
237 	bool radar_required;
238 	int err;
239 
240 	sdata_assert_lock(sdata);
241 
242 	/* Reset own TSF to allow time synchronization work. */
243 	drv_reset_tsf(local, sdata);
244 
245 	if (!ether_addr_equal(ifibss->bssid, bssid))
246 		sta_info_flush(sdata);
247 
248 	/* if merging, indicate to driver that we leave the old IBSS */
249 	if (sdata->vif.bss_conf.ibss_joined) {
250 		sdata->vif.bss_conf.ibss_joined = false;
251 		sdata->vif.bss_conf.ibss_creator = false;
252 		sdata->vif.bss_conf.enable_beacon = false;
253 		netif_carrier_off(sdata->dev);
254 		ieee80211_bss_info_change_notify(sdata,
255 						 BSS_CHANGED_IBSS |
256 						 BSS_CHANGED_BEACON_ENABLED);
257 		drv_leave_ibss(local, sdata);
258 	}
259 
260 	presp = rcu_dereference_protected(ifibss->presp,
261 					  lockdep_is_held(&sdata->wdev.mtx));
262 	RCU_INIT_POINTER(ifibss->presp, NULL);
263 	if (presp)
264 		kfree_rcu(presp, rcu_head);
265 
266 	/* make a copy of the chandef, it could be modified below. */
267 	chandef = *req_chandef;
268 	chan = chandef.chan;
269 	if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
270 				     NL80211_IFTYPE_ADHOC)) {
271 		if (chandef.width == NL80211_CHAN_WIDTH_5 ||
272 		    chandef.width == NL80211_CHAN_WIDTH_10 ||
273 		    chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
274 		    chandef.width == NL80211_CHAN_WIDTH_20) {
275 			sdata_info(sdata,
276 				   "Failed to join IBSS, beacons forbidden\n");
277 			return;
278 		}
279 		chandef.width = NL80211_CHAN_WIDTH_20;
280 		chandef.center_freq1 = chan->center_freq;
281 		/* check again for downgraded chandef */
282 		if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
283 					     NL80211_IFTYPE_ADHOC)) {
284 			sdata_info(sdata,
285 				   "Failed to join IBSS, beacons forbidden\n");
286 			return;
287 		}
288 	}
289 
290 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
291 					    &chandef, NL80211_IFTYPE_ADHOC);
292 	if (err < 0) {
293 		sdata_info(sdata,
294 			   "Failed to join IBSS, invalid chandef\n");
295 		return;
296 	}
297 	if (err > 0 && !ifibss->userspace_handles_dfs) {
298 		sdata_info(sdata,
299 			   "Failed to join IBSS, DFS channel without control program\n");
300 		return;
301 	}
302 
303 	radar_required = err;
304 
305 	mutex_lock(&local->mtx);
306 	if (ieee80211_vif_use_channel(sdata, &chandef,
307 				      ifibss->fixed_channel ?
308 					IEEE80211_CHANCTX_SHARED :
309 					IEEE80211_CHANCTX_EXCLUSIVE)) {
310 		sdata_info(sdata, "Failed to join IBSS, no channel context\n");
311 		mutex_unlock(&local->mtx);
312 		return;
313 	}
314 	sdata->radar_required = radar_required;
315 	mutex_unlock(&local->mtx);
316 
317 	memcpy(ifibss->bssid, bssid, ETH_ALEN);
318 
319 	presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
320 					   capability, tsf, &chandef,
321 					   &have_higher_than_11mbit, NULL);
322 	if (!presp)
323 		return;
324 
325 	rcu_assign_pointer(ifibss->presp, presp);
326 	mgmt = (void *)presp->head;
327 
328 	sdata->vif.bss_conf.enable_beacon = true;
329 	sdata->vif.bss_conf.beacon_int = beacon_int;
330 	sdata->vif.bss_conf.basic_rates = basic_rates;
331 	sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
332 	memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
333 	bss_change = BSS_CHANGED_BEACON_INT;
334 	bss_change |= ieee80211_reset_erp_info(sdata);
335 	bss_change |= BSS_CHANGED_BSSID;
336 	bss_change |= BSS_CHANGED_BEACON;
337 	bss_change |= BSS_CHANGED_BEACON_ENABLED;
338 	bss_change |= BSS_CHANGED_BASIC_RATES;
339 	bss_change |= BSS_CHANGED_HT;
340 	bss_change |= BSS_CHANGED_IBSS;
341 	bss_change |= BSS_CHANGED_SSID;
342 
343 	/*
344 	 * In 5 GHz/802.11a, we can always use short slot time.
345 	 * (IEEE 802.11-2012 18.3.8.7)
346 	 *
347 	 * In 2.4GHz, we must always use long slots in IBSS for compatibility
348 	 * reasons.
349 	 * (IEEE 802.11-2012 19.4.5)
350 	 *
351 	 * HT follows these specifications (IEEE 802.11-2012 20.3.18)
352 	 */
353 	sdata->vif.bss_conf.use_short_slot = chan->band == NL80211_BAND_5GHZ;
354 	bss_change |= BSS_CHANGED_ERP_SLOT;
355 
356 	/* cf. IEEE 802.11 9.2.12 */
357 	if (chan->band == NL80211_BAND_2GHZ && have_higher_than_11mbit)
358 		sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
359 	else
360 		sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
361 
362 	ieee80211_set_wmm_default(sdata, true, false);
363 
364 	sdata->vif.bss_conf.ibss_joined = true;
365 	sdata->vif.bss_conf.ibss_creator = creator;
366 
367 	err = drv_join_ibss(local, sdata);
368 	if (err) {
369 		sdata->vif.bss_conf.ibss_joined = false;
370 		sdata->vif.bss_conf.ibss_creator = false;
371 		sdata->vif.bss_conf.enable_beacon = false;
372 		sdata->vif.bss_conf.ssid_len = 0;
373 		RCU_INIT_POINTER(ifibss->presp, NULL);
374 		kfree_rcu(presp, rcu_head);
375 		mutex_lock(&local->mtx);
376 		ieee80211_vif_release_channel(sdata);
377 		mutex_unlock(&local->mtx);
378 		sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
379 			   err);
380 		return;
381 	}
382 
383 	ieee80211_bss_info_change_notify(sdata, bss_change);
384 
385 	ifibss->state = IEEE80211_IBSS_MLME_JOINED;
386 	mod_timer(&ifibss->timer,
387 		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
388 
389 	bss_meta.chan = chan;
390 	bss_meta.scan_width = cfg80211_chandef_to_scan_width(&chandef);
391 	bss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, mgmt,
392 					     presp->head_len, GFP_KERNEL);
393 
394 	cfg80211_put_bss(local->hw.wiphy, bss);
395 	netif_carrier_on(sdata->dev);
396 	cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
397 }
398 
ieee80211_sta_join_ibss(struct ieee80211_sub_if_data * sdata,struct ieee80211_bss * bss)399 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
400 				    struct ieee80211_bss *bss)
401 {
402 	struct cfg80211_bss *cbss =
403 		container_of((void *)bss, struct cfg80211_bss, priv);
404 	struct ieee80211_supported_band *sband;
405 	struct cfg80211_chan_def chandef;
406 	u32 basic_rates;
407 	int i, j;
408 	u16 beacon_int = cbss->beacon_interval;
409 	const struct cfg80211_bss_ies *ies;
410 	enum nl80211_channel_type chan_type;
411 	u64 tsf;
412 	u32 rate_flags;
413 	int shift;
414 
415 	sdata_assert_lock(sdata);
416 
417 	if (beacon_int < 10)
418 		beacon_int = 10;
419 
420 	switch (sdata->u.ibss.chandef.width) {
421 	case NL80211_CHAN_WIDTH_20_NOHT:
422 	case NL80211_CHAN_WIDTH_20:
423 	case NL80211_CHAN_WIDTH_40:
424 		chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
425 		cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
426 		break;
427 	case NL80211_CHAN_WIDTH_5:
428 	case NL80211_CHAN_WIDTH_10:
429 		cfg80211_chandef_create(&chandef, cbss->channel,
430 					NL80211_CHAN_NO_HT);
431 		chandef.width = sdata->u.ibss.chandef.width;
432 		break;
433 	case NL80211_CHAN_WIDTH_80:
434 	case NL80211_CHAN_WIDTH_80P80:
435 	case NL80211_CHAN_WIDTH_160:
436 		chandef = sdata->u.ibss.chandef;
437 		chandef.chan = cbss->channel;
438 		break;
439 	default:
440 		/* fall back to 20 MHz for unsupported modes */
441 		cfg80211_chandef_create(&chandef, cbss->channel,
442 					NL80211_CHAN_NO_HT);
443 		break;
444 	}
445 
446 	sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
447 	rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
448 	shift = ieee80211_vif_get_shift(&sdata->vif);
449 
450 	basic_rates = 0;
451 
452 	for (i = 0; i < bss->supp_rates_len; i++) {
453 		int rate = bss->supp_rates[i] & 0x7f;
454 		bool is_basic = !!(bss->supp_rates[i] & 0x80);
455 
456 		for (j = 0; j < sband->n_bitrates; j++) {
457 			int brate;
458 			if ((rate_flags & sband->bitrates[j].flags)
459 			    != rate_flags)
460 				continue;
461 
462 			brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
463 					     5 * (1 << shift));
464 			if (brate == rate) {
465 				if (is_basic)
466 					basic_rates |= BIT(j);
467 				break;
468 			}
469 		}
470 	}
471 
472 	rcu_read_lock();
473 	ies = rcu_dereference(cbss->ies);
474 	tsf = ies->tsf;
475 	rcu_read_unlock();
476 
477 	__ieee80211_sta_join_ibss(sdata, cbss->bssid,
478 				  beacon_int,
479 				  &chandef,
480 				  basic_rates,
481 				  cbss->capability,
482 				  tsf, false);
483 }
484 
ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data * sdata,struct cfg80211_csa_settings * csa_settings)485 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
486 			      struct cfg80211_csa_settings *csa_settings)
487 {
488 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
489 	struct beacon_data *presp, *old_presp;
490 	struct cfg80211_bss *cbss;
491 	const struct cfg80211_bss_ies *ies;
492 	u16 capability = WLAN_CAPABILITY_IBSS;
493 	u64 tsf;
494 	int ret = 0;
495 
496 	sdata_assert_lock(sdata);
497 
498 	if (ifibss->privacy)
499 		capability |= WLAN_CAPABILITY_PRIVACY;
500 
501 	cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
502 				ifibss->bssid, ifibss->ssid,
503 				ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS,
504 				IEEE80211_PRIVACY(ifibss->privacy));
505 
506 	if (WARN_ON(!cbss)) {
507 		ret = -EINVAL;
508 		goto out;
509 	}
510 
511 	rcu_read_lock();
512 	ies = rcu_dereference(cbss->ies);
513 	tsf = ies->tsf;
514 	rcu_read_unlock();
515 	cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
516 
517 	old_presp = rcu_dereference_protected(ifibss->presp,
518 					  lockdep_is_held(&sdata->wdev.mtx));
519 
520 	presp = ieee80211_ibss_build_presp(sdata,
521 					   sdata->vif.bss_conf.beacon_int,
522 					   sdata->vif.bss_conf.basic_rates,
523 					   capability, tsf, &ifibss->chandef,
524 					   NULL, csa_settings);
525 	if (!presp) {
526 		ret = -ENOMEM;
527 		goto out;
528 	}
529 
530 	rcu_assign_pointer(ifibss->presp, presp);
531 	if (old_presp)
532 		kfree_rcu(old_presp, rcu_head);
533 
534 	return BSS_CHANGED_BEACON;
535  out:
536 	return ret;
537 }
538 
ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data * sdata)539 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
540 {
541 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
542 	struct cfg80211_bss *cbss;
543 	int err, changed = 0;
544 
545 	sdata_assert_lock(sdata);
546 
547 	/* update cfg80211 bss information with the new channel */
548 	if (!is_zero_ether_addr(ifibss->bssid)) {
549 		cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
550 					ifibss->chandef.chan,
551 					ifibss->bssid, ifibss->ssid,
552 					ifibss->ssid_len,
553 					IEEE80211_BSS_TYPE_IBSS,
554 					IEEE80211_PRIVACY(ifibss->privacy));
555 		/* XXX: should not really modify cfg80211 data */
556 		if (cbss) {
557 			cbss->channel = sdata->csa_chandef.chan;
558 			cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
559 		}
560 	}
561 
562 	ifibss->chandef = sdata->csa_chandef;
563 
564 	/* generate the beacon */
565 	err = ieee80211_ibss_csa_beacon(sdata, NULL);
566 	if (err < 0)
567 		return err;
568 
569 	changed |= err;
570 
571 	return changed;
572 }
573 
ieee80211_ibss_stop(struct ieee80211_sub_if_data * sdata)574 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
575 {
576 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
577 
578 	cancel_work_sync(&ifibss->csa_connection_drop_work);
579 }
580 
ieee80211_ibss_finish_sta(struct sta_info * sta)581 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
582 	__acquires(RCU)
583 {
584 	struct ieee80211_sub_if_data *sdata = sta->sdata;
585 	u8 addr[ETH_ALEN];
586 
587 	memcpy(addr, sta->sta.addr, ETH_ALEN);
588 
589 	ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
590 
591 	sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
592 	sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
593 	/* authorize the station only if the network is not RSN protected. If
594 	 * not wait for the userspace to authorize it */
595 	if (!sta->sdata->u.ibss.control_port)
596 		sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
597 
598 	rate_control_rate_init(sta);
599 
600 	/* If it fails, maybe we raced another insertion? */
601 	if (sta_info_insert_rcu(sta))
602 		return sta_info_get(sdata, addr);
603 	return sta;
604 }
605 
606 static struct sta_info *
ieee80211_ibss_add_sta(struct ieee80211_sub_if_data * sdata,const u8 * bssid,const u8 * addr,u32 supp_rates)607 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
608 		       const u8 *addr, u32 supp_rates)
609 	__acquires(RCU)
610 {
611 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
612 	struct ieee80211_local *local = sdata->local;
613 	struct sta_info *sta;
614 	struct ieee80211_chanctx_conf *chanctx_conf;
615 	struct ieee80211_supported_band *sband;
616 	enum nl80211_bss_scan_width scan_width;
617 	int band;
618 
619 	/*
620 	 * XXX: Consider removing the least recently used entry and
621 	 * 	allow new one to be added.
622 	 */
623 	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
624 		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
625 				    sdata->name, addr);
626 		rcu_read_lock();
627 		return NULL;
628 	}
629 
630 	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
631 		rcu_read_lock();
632 		return NULL;
633 	}
634 
635 	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
636 		rcu_read_lock();
637 		return NULL;
638 	}
639 
640 	rcu_read_lock();
641 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
642 	if (WARN_ON_ONCE(!chanctx_conf))
643 		return NULL;
644 	band = chanctx_conf->def.chan->band;
645 	scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
646 	rcu_read_unlock();
647 
648 	sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
649 	if (!sta) {
650 		rcu_read_lock();
651 		return NULL;
652 	}
653 
654 	/* make sure mandatory rates are always added */
655 	sband = local->hw.wiphy->bands[band];
656 	sta->sta.supp_rates[band] = supp_rates |
657 			ieee80211_mandatory_rates(sband, scan_width);
658 
659 	return ieee80211_ibss_finish_sta(sta);
660 }
661 
ieee80211_sta_active_ibss(struct ieee80211_sub_if_data * sdata)662 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
663 {
664 	struct ieee80211_local *local = sdata->local;
665 	int active = 0;
666 	struct sta_info *sta;
667 
668 	sdata_assert_lock(sdata);
669 
670 	rcu_read_lock();
671 
672 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
673 		unsigned long last_active = ieee80211_sta_last_active(sta);
674 
675 		if (sta->sdata == sdata &&
676 		    time_is_after_jiffies(last_active +
677 					  IEEE80211_IBSS_MERGE_INTERVAL)) {
678 			active++;
679 			break;
680 		}
681 	}
682 
683 	rcu_read_unlock();
684 
685 	return active;
686 }
687 
ieee80211_ibss_disconnect(struct ieee80211_sub_if_data * sdata)688 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
689 {
690 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
691 	struct ieee80211_local *local = sdata->local;
692 	struct cfg80211_bss *cbss;
693 	struct beacon_data *presp;
694 	struct sta_info *sta;
695 
696 	if (!is_zero_ether_addr(ifibss->bssid)) {
697 		cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
698 					ifibss->bssid, ifibss->ssid,
699 					ifibss->ssid_len,
700 					IEEE80211_BSS_TYPE_IBSS,
701 					IEEE80211_PRIVACY(ifibss->privacy));
702 
703 		if (cbss) {
704 			cfg80211_unlink_bss(local->hw.wiphy, cbss);
705 			cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
706 		}
707 	}
708 
709 	ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
710 
711 	sta_info_flush(sdata);
712 
713 	spin_lock_bh(&ifibss->incomplete_lock);
714 	while (!list_empty(&ifibss->incomplete_stations)) {
715 		sta = list_first_entry(&ifibss->incomplete_stations,
716 				       struct sta_info, list);
717 		list_del(&sta->list);
718 		spin_unlock_bh(&ifibss->incomplete_lock);
719 
720 		sta_info_free(local, sta);
721 		spin_lock_bh(&ifibss->incomplete_lock);
722 	}
723 	spin_unlock_bh(&ifibss->incomplete_lock);
724 
725 	netif_carrier_off(sdata->dev);
726 
727 	sdata->vif.bss_conf.ibss_joined = false;
728 	sdata->vif.bss_conf.ibss_creator = false;
729 	sdata->vif.bss_conf.enable_beacon = false;
730 	sdata->vif.bss_conf.ssid_len = 0;
731 
732 	/* remove beacon */
733 	presp = rcu_dereference_protected(ifibss->presp,
734 					  lockdep_is_held(&sdata->wdev.mtx));
735 	RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
736 	if (presp)
737 		kfree_rcu(presp, rcu_head);
738 
739 	clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
740 	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
741 						BSS_CHANGED_IBSS);
742 	drv_leave_ibss(local, sdata);
743 	mutex_lock(&local->mtx);
744 	ieee80211_vif_release_channel(sdata);
745 	mutex_unlock(&local->mtx);
746 }
747 
ieee80211_csa_connection_drop_work(struct work_struct * work)748 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
749 {
750 	struct ieee80211_sub_if_data *sdata =
751 		container_of(work, struct ieee80211_sub_if_data,
752 			     u.ibss.csa_connection_drop_work);
753 
754 	sdata_lock(sdata);
755 
756 	ieee80211_ibss_disconnect(sdata);
757 	synchronize_rcu();
758 	skb_queue_purge(&sdata->skb_queue);
759 
760 	/* trigger a scan to find another IBSS network to join */
761 	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
762 
763 	sdata_unlock(sdata);
764 }
765 
ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data * sdata)766 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
767 {
768 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
769 	int err;
770 
771 	/* if the current channel is a DFS channel, mark the channel as
772 	 * unavailable.
773 	 */
774 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
775 					    &ifibss->chandef,
776 					    NL80211_IFTYPE_ADHOC);
777 	if (err > 0)
778 		cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
779 				     GFP_ATOMIC);
780 }
781 
782 static bool
ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data * sdata,struct ieee802_11_elems * elems,bool beacon)783 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
784 				  struct ieee802_11_elems *elems,
785 				  bool beacon)
786 {
787 	struct cfg80211_csa_settings params;
788 	struct ieee80211_csa_ie csa_ie;
789 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
790 	enum nl80211_channel_type ch_type;
791 	int err;
792 	u32 sta_flags;
793 
794 	sdata_assert_lock(sdata);
795 
796 	sta_flags = IEEE80211_STA_DISABLE_VHT;
797 	switch (ifibss->chandef.width) {
798 	case NL80211_CHAN_WIDTH_5:
799 	case NL80211_CHAN_WIDTH_10:
800 	case NL80211_CHAN_WIDTH_20_NOHT:
801 		sta_flags |= IEEE80211_STA_DISABLE_HT;
802 		/* fall through */
803 	case NL80211_CHAN_WIDTH_20:
804 		sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
805 		break;
806 	default:
807 		break;
808 	}
809 
810 	memset(&params, 0, sizeof(params));
811 	memset(&csa_ie, 0, sizeof(csa_ie));
812 	err = ieee80211_parse_ch_switch_ie(sdata, elems,
813 					   ifibss->chandef.chan->band,
814 					   sta_flags, ifibss->bssid, &csa_ie);
815 	/* can't switch to destination channel, fail */
816 	if (err < 0)
817 		goto disconnect;
818 
819 	/* did not contain a CSA */
820 	if (err)
821 		return false;
822 
823 	/* channel switch is not supported, disconnect */
824 	if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
825 		goto disconnect;
826 
827 	params.count = csa_ie.count;
828 	params.chandef = csa_ie.chandef;
829 
830 	switch (ifibss->chandef.width) {
831 	case NL80211_CHAN_WIDTH_20_NOHT:
832 	case NL80211_CHAN_WIDTH_20:
833 	case NL80211_CHAN_WIDTH_40:
834 		/* keep our current HT mode (HT20/HT40+/HT40-), even if
835 		 * another mode  has been announced. The mode is not adopted
836 		 * within the beacon while doing CSA and we should therefore
837 		 * keep the mode which we announce.
838 		 */
839 		ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
840 		cfg80211_chandef_create(&params.chandef, params.chandef.chan,
841 					ch_type);
842 		break;
843 	case NL80211_CHAN_WIDTH_5:
844 	case NL80211_CHAN_WIDTH_10:
845 		if (params.chandef.width != ifibss->chandef.width) {
846 			sdata_info(sdata,
847 				   "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
848 				   ifibss->bssid,
849 				   params.chandef.chan->center_freq,
850 				   params.chandef.width,
851 				   params.chandef.center_freq1,
852 				   params.chandef.center_freq2);
853 			goto disconnect;
854 		}
855 		break;
856 	default:
857 		/* should not happen, sta_flags should prevent VHT modes. */
858 		WARN_ON(1);
859 		goto disconnect;
860 	}
861 
862 	if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
863 				     NL80211_IFTYPE_ADHOC)) {
864 		sdata_info(sdata,
865 			   "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
866 			   ifibss->bssid,
867 			   params.chandef.chan->center_freq,
868 			   params.chandef.width,
869 			   params.chandef.center_freq1,
870 			   params.chandef.center_freq2);
871 		goto disconnect;
872 	}
873 
874 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
875 					    &params.chandef,
876 					    NL80211_IFTYPE_ADHOC);
877 	if (err < 0)
878 		goto disconnect;
879 	if (err > 0 && !ifibss->userspace_handles_dfs) {
880 		/* IBSS-DFS only allowed with a control program */
881 		goto disconnect;
882 	}
883 
884 	params.radar_required = err;
885 
886 	if (cfg80211_chandef_identical(&params.chandef,
887 				       &sdata->vif.bss_conf.chandef)) {
888 		ibss_dbg(sdata,
889 			 "received csa with an identical chandef, ignoring\n");
890 		return true;
891 	}
892 
893 	/* all checks done, now perform the channel switch. */
894 	ibss_dbg(sdata,
895 		 "received channel switch announcement to go to channel %d MHz\n",
896 		 params.chandef.chan->center_freq);
897 
898 	params.block_tx = !!csa_ie.mode;
899 
900 	if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
901 				     &params))
902 		goto disconnect;
903 
904 	ieee80211_ibss_csa_mark_radar(sdata);
905 
906 	return true;
907 disconnect:
908 	ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
909 	ieee80211_queue_work(&sdata->local->hw,
910 			     &ifibss->csa_connection_drop_work);
911 
912 	ieee80211_ibss_csa_mark_radar(sdata);
913 
914 	return true;
915 }
916 
917 static void
ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data * sdata,struct ieee80211_mgmt * mgmt,size_t len,struct ieee80211_rx_status * rx_status,struct ieee802_11_elems * elems)918 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
919 				struct ieee80211_mgmt *mgmt, size_t len,
920 				struct ieee80211_rx_status *rx_status,
921 				struct ieee802_11_elems *elems)
922 {
923 	int required_len;
924 
925 	if (len < IEEE80211_MIN_ACTION_SIZE + 1)
926 		return;
927 
928 	/* CSA is the only action we handle for now */
929 	if (mgmt->u.action.u.measurement.action_code !=
930 	    WLAN_ACTION_SPCT_CHL_SWITCH)
931 		return;
932 
933 	required_len = IEEE80211_MIN_ACTION_SIZE +
934 		       sizeof(mgmt->u.action.u.chan_switch);
935 	if (len < required_len)
936 		return;
937 
938 	if (!sdata->vif.csa_active)
939 		ieee80211_ibss_process_chanswitch(sdata, elems, false);
940 }
941 
ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data * sdata,struct ieee80211_mgmt * mgmt,size_t len)942 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
943 					  struct ieee80211_mgmt *mgmt,
944 					  size_t len)
945 {
946 	u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
947 
948 	if (len < IEEE80211_DEAUTH_FRAME_LEN)
949 		return;
950 
951 	ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
952 		 mgmt->sa, mgmt->da, mgmt->bssid, reason);
953 	sta_info_destroy_addr(sdata, mgmt->sa);
954 }
955 
ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data * sdata,struct ieee80211_mgmt * mgmt,size_t len)956 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
957 					struct ieee80211_mgmt *mgmt,
958 					size_t len)
959 {
960 	u16 auth_alg, auth_transaction;
961 
962 	sdata_assert_lock(sdata);
963 
964 	if (len < 24 + 6)
965 		return;
966 
967 	auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
968 	auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
969 
970 	ibss_dbg(sdata,
971 		 "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
972 		 mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
973 
974 	if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
975 		return;
976 
977 	/*
978 	 * IEEE 802.11 standard does not require authentication in IBSS
979 	 * networks and most implementations do not seem to use it.
980 	 * However, try to reply to authentication attempts if someone
981 	 * has actually implemented this.
982 	 */
983 	ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
984 			    mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
985 }
986 
ieee80211_update_sta_info(struct ieee80211_sub_if_data * sdata,struct ieee80211_mgmt * mgmt,size_t len,struct ieee80211_rx_status * rx_status,struct ieee802_11_elems * elems,struct ieee80211_channel * channel)987 static void ieee80211_update_sta_info(struct ieee80211_sub_if_data *sdata,
988 				      struct ieee80211_mgmt *mgmt, size_t len,
989 				      struct ieee80211_rx_status *rx_status,
990 				      struct ieee802_11_elems *elems,
991 				      struct ieee80211_channel *channel)
992 {
993 	struct sta_info *sta;
994 	enum nl80211_band band = rx_status->band;
995 	enum nl80211_bss_scan_width scan_width;
996 	struct ieee80211_local *local = sdata->local;
997 	struct ieee80211_supported_band *sband;
998 	bool rates_updated = false;
999 	u32 supp_rates = 0;
1000 
1001 	if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1002 		return;
1003 
1004 	if (!ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid))
1005 		return;
1006 
1007 	sband = local->hw.wiphy->bands[band];
1008 	if (WARN_ON(!sband))
1009 		return;
1010 
1011 	rcu_read_lock();
1012 	sta = sta_info_get(sdata, mgmt->sa);
1013 
1014 	if (elems->supp_rates) {
1015 		supp_rates = ieee80211_sta_get_rates(sdata, elems,
1016 						     band, NULL);
1017 		if (sta) {
1018 			u32 prev_rates;
1019 
1020 			prev_rates = sta->sta.supp_rates[band];
1021 			/* make sure mandatory rates are always added */
1022 			scan_width = NL80211_BSS_CHAN_WIDTH_20;
1023 			if (rx_status->flag & RX_FLAG_5MHZ)
1024 				scan_width = NL80211_BSS_CHAN_WIDTH_5;
1025 			if (rx_status->flag & RX_FLAG_10MHZ)
1026 				scan_width = NL80211_BSS_CHAN_WIDTH_10;
1027 
1028 			sta->sta.supp_rates[band] = supp_rates |
1029 				ieee80211_mandatory_rates(sband, scan_width);
1030 			if (sta->sta.supp_rates[band] != prev_rates) {
1031 				ibss_dbg(sdata,
1032 					 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1033 					 sta->sta.addr, prev_rates,
1034 					 sta->sta.supp_rates[band]);
1035 				rates_updated = true;
1036 			}
1037 		} else {
1038 			rcu_read_unlock();
1039 			sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1040 						     mgmt->sa, supp_rates);
1041 		}
1042 	}
1043 
1044 	if (sta && !sta->sta.wme &&
1045 	    elems->wmm_info && local->hw.queues >= IEEE80211_NUM_ACS) {
1046 		sta->sta.wme = true;
1047 		ieee80211_check_fast_xmit(sta);
1048 	}
1049 
1050 	if (sta && elems->ht_operation && elems->ht_cap_elem &&
1051 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1052 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1053 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1054 		/* we both use HT */
1055 		struct ieee80211_ht_cap htcap_ie;
1056 		struct cfg80211_chan_def chandef;
1057 		enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
1058 
1059 		cfg80211_chandef_create(&chandef, channel, NL80211_CHAN_NO_HT);
1060 		ieee80211_chandef_ht_oper(elems->ht_operation, &chandef);
1061 
1062 		memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1063 		rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
1064 								   &htcap_ie,
1065 								   sta);
1066 
1067 		if (elems->vht_operation && elems->vht_cap_elem &&
1068 		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20 &&
1069 		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_40) {
1070 			/* we both use VHT */
1071 			struct ieee80211_vht_cap cap_ie;
1072 			struct ieee80211_sta_vht_cap cap = sta->sta.vht_cap;
1073 
1074 			ieee80211_chandef_vht_oper(elems->vht_operation,
1075 						   &chandef);
1076 			memcpy(&cap_ie, elems->vht_cap_elem, sizeof(cap_ie));
1077 			ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
1078 							    &cap_ie, sta);
1079 			if (memcmp(&cap, &sta->sta.vht_cap, sizeof(cap)))
1080 				rates_updated |= true;
1081 		}
1082 
1083 		if (bw != sta->sta.bandwidth)
1084 			rates_updated |= true;
1085 
1086 		if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
1087 						 &chandef))
1088 			WARN_ON_ONCE(1);
1089 	}
1090 
1091 	if (sta && rates_updated) {
1092 		u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
1093 		u8 rx_nss = sta->sta.rx_nss;
1094 
1095 		/* Force rx_nss recalculation */
1096 		sta->sta.rx_nss = 0;
1097 		rate_control_rate_init(sta);
1098 		if (sta->sta.rx_nss != rx_nss)
1099 			changed |= IEEE80211_RC_NSS_CHANGED;
1100 
1101 		drv_sta_rc_update(local, sdata, &sta->sta, changed);
1102 	}
1103 
1104 	rcu_read_unlock();
1105 }
1106 
ieee80211_rx_bss_info(struct ieee80211_sub_if_data * sdata,struct ieee80211_mgmt * mgmt,size_t len,struct ieee80211_rx_status * rx_status,struct ieee802_11_elems * elems)1107 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1108 				  struct ieee80211_mgmt *mgmt, size_t len,
1109 				  struct ieee80211_rx_status *rx_status,
1110 				  struct ieee802_11_elems *elems)
1111 {
1112 	struct ieee80211_local *local = sdata->local;
1113 	struct cfg80211_bss *cbss;
1114 	struct ieee80211_bss *bss;
1115 	struct ieee80211_channel *channel;
1116 	u64 beacon_timestamp, rx_timestamp;
1117 	u32 supp_rates = 0;
1118 	enum nl80211_band band = rx_status->band;
1119 
1120 	channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1121 	if (!channel)
1122 		return;
1123 
1124 	ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
1125 
1126 	bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1127 					channel);
1128 	if (!bss)
1129 		return;
1130 
1131 	cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1132 
1133 	/* same for beacon and probe response */
1134 	beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1135 
1136 	/* check if we need to merge IBSS */
1137 
1138 	/* not an IBSS */
1139 	if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1140 		goto put_bss;
1141 
1142 	/* different channel */
1143 	if (sdata->u.ibss.fixed_channel &&
1144 	    sdata->u.ibss.chandef.chan != cbss->channel)
1145 		goto put_bss;
1146 
1147 	/* different SSID */
1148 	if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1149 	    memcmp(elems->ssid, sdata->u.ibss.ssid,
1150 				sdata->u.ibss.ssid_len))
1151 		goto put_bss;
1152 
1153 	/* process channel switch */
1154 	if (sdata->vif.csa_active ||
1155 	    ieee80211_ibss_process_chanswitch(sdata, elems, true))
1156 		goto put_bss;
1157 
1158 	/* same BSSID */
1159 	if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1160 		goto put_bss;
1161 
1162 	/* we use a fixed BSSID */
1163 	if (sdata->u.ibss.fixed_bssid)
1164 		goto put_bss;
1165 
1166 	if (ieee80211_have_rx_timestamp(rx_status)) {
1167 		/* time when timestamp field was received */
1168 		rx_timestamp =
1169 			ieee80211_calculate_rx_timestamp(local, rx_status,
1170 							 len + FCS_LEN, 24);
1171 	} else {
1172 		/*
1173 		 * second best option: get current TSF
1174 		 * (will return -1 if not supported)
1175 		 */
1176 		rx_timestamp = drv_get_tsf(local, sdata);
1177 	}
1178 
1179 	ibss_dbg(sdata,
1180 		 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1181 		 mgmt->sa, mgmt->bssid,
1182 		 (unsigned long long)rx_timestamp,
1183 		 (unsigned long long)beacon_timestamp,
1184 		 (unsigned long long)(rx_timestamp - beacon_timestamp),
1185 		 jiffies);
1186 
1187 	if (beacon_timestamp > rx_timestamp) {
1188 		ibss_dbg(sdata,
1189 			 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1190 			 mgmt->bssid);
1191 		ieee80211_sta_join_ibss(sdata, bss);
1192 		supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1193 		ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1194 				       supp_rates);
1195 		rcu_read_unlock();
1196 	}
1197 
1198  put_bss:
1199 	ieee80211_rx_bss_put(local, bss);
1200 }
1201 
ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data * sdata,const u8 * bssid,const u8 * addr,u32 supp_rates)1202 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1203 			      const u8 *bssid, const u8 *addr,
1204 			      u32 supp_rates)
1205 {
1206 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1207 	struct ieee80211_local *local = sdata->local;
1208 	struct sta_info *sta;
1209 	struct ieee80211_chanctx_conf *chanctx_conf;
1210 	struct ieee80211_supported_band *sband;
1211 	enum nl80211_bss_scan_width scan_width;
1212 	int band;
1213 
1214 	/*
1215 	 * XXX: Consider removing the least recently used entry and
1216 	 * 	allow new one to be added.
1217 	 */
1218 	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1219 		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1220 				    sdata->name, addr);
1221 		return;
1222 	}
1223 
1224 	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1225 		return;
1226 
1227 	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1228 		return;
1229 
1230 	rcu_read_lock();
1231 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1232 	if (WARN_ON_ONCE(!chanctx_conf)) {
1233 		rcu_read_unlock();
1234 		return;
1235 	}
1236 	band = chanctx_conf->def.chan->band;
1237 	scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1238 	rcu_read_unlock();
1239 
1240 	sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1241 	if (!sta)
1242 		return;
1243 
1244 	/* make sure mandatory rates are always added */
1245 	sband = local->hw.wiphy->bands[band];
1246 	sta->sta.supp_rates[band] = supp_rates |
1247 			ieee80211_mandatory_rates(sband, scan_width);
1248 
1249 	spin_lock(&ifibss->incomplete_lock);
1250 	list_add(&sta->list, &ifibss->incomplete_stations);
1251 	spin_unlock(&ifibss->incomplete_lock);
1252 	ieee80211_queue_work(&local->hw, &sdata->work);
1253 }
1254 
ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data * sdata)1255 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1256 {
1257 	struct ieee80211_local *local = sdata->local;
1258 	struct sta_info *sta, *tmp;
1259 	unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1260 	unsigned long exp_rsn = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1261 
1262 	mutex_lock(&local->sta_mtx);
1263 
1264 	list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1265 		unsigned long last_active = ieee80211_sta_last_active(sta);
1266 
1267 		if (sdata != sta->sdata)
1268 			continue;
1269 
1270 		if (time_is_before_jiffies(last_active + exp_time) ||
1271 		    (time_is_before_jiffies(last_active + exp_rsn) &&
1272 		     sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1273 			sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1274 				sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1275 				"not authorized " : "", sta->sta.addr);
1276 
1277 			WARN_ON(__sta_info_destroy(sta));
1278 		}
1279 	}
1280 
1281 	mutex_unlock(&local->sta_mtx);
1282 }
1283 
1284 /*
1285  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1286  */
1287 
ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data * sdata)1288 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1289 {
1290 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1291 	enum nl80211_bss_scan_width scan_width;
1292 
1293 	sdata_assert_lock(sdata);
1294 
1295 	mod_timer(&ifibss->timer,
1296 		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1297 
1298 	ieee80211_ibss_sta_expire(sdata);
1299 
1300 	if (time_before(jiffies, ifibss->last_scan_completed +
1301 		       IEEE80211_IBSS_MERGE_INTERVAL))
1302 		return;
1303 
1304 	if (ieee80211_sta_active_ibss(sdata))
1305 		return;
1306 
1307 	if (ifibss->fixed_channel)
1308 		return;
1309 
1310 	sdata_info(sdata,
1311 		   "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1312 
1313 	scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1314 	ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1315 				    NULL, 0, scan_width);
1316 }
1317 
ieee80211_sta_create_ibss(struct ieee80211_sub_if_data * sdata)1318 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1319 {
1320 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1321 	u8 bssid[ETH_ALEN];
1322 	u16 capability;
1323 	int i;
1324 
1325 	sdata_assert_lock(sdata);
1326 
1327 	if (ifibss->fixed_bssid) {
1328 		memcpy(bssid, ifibss->bssid, ETH_ALEN);
1329 	} else {
1330 		/* Generate random, not broadcast, locally administered BSSID. Mix in
1331 		 * own MAC address to make sure that devices that do not have proper
1332 		 * random number generator get different BSSID. */
1333 		get_random_bytes(bssid, ETH_ALEN);
1334 		for (i = 0; i < ETH_ALEN; i++)
1335 			bssid[i] ^= sdata->vif.addr[i];
1336 		bssid[0] &= ~0x01;
1337 		bssid[0] |= 0x02;
1338 	}
1339 
1340 	sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1341 
1342 	capability = WLAN_CAPABILITY_IBSS;
1343 
1344 	if (ifibss->privacy)
1345 		capability |= WLAN_CAPABILITY_PRIVACY;
1346 
1347 	__ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1348 				  &ifibss->chandef, ifibss->basic_rates,
1349 				  capability, 0, true);
1350 }
1351 
ibss_setup_channels(struct wiphy * wiphy,struct ieee80211_channel ** channels,unsigned int channels_max,u32 center_freq,u32 width)1352 static unsigned ibss_setup_channels(struct wiphy *wiphy,
1353 				    struct ieee80211_channel **channels,
1354 				    unsigned int channels_max,
1355 				    u32 center_freq, u32 width)
1356 {
1357 	struct ieee80211_channel *chan = NULL;
1358 	unsigned int n_chan = 0;
1359 	u32 start_freq, end_freq, freq;
1360 
1361 	if (width <= 20) {
1362 		start_freq = center_freq;
1363 		end_freq = center_freq;
1364 	} else {
1365 		start_freq = center_freq - width / 2 + 10;
1366 		end_freq = center_freq + width / 2 - 10;
1367 	}
1368 
1369 	for (freq = start_freq; freq <= end_freq; freq += 20) {
1370 		chan = ieee80211_get_channel(wiphy, freq);
1371 		if (!chan)
1372 			continue;
1373 		if (n_chan >= channels_max)
1374 			return n_chan;
1375 
1376 		channels[n_chan] = chan;
1377 		n_chan++;
1378 	}
1379 
1380 	return n_chan;
1381 }
1382 
1383 static unsigned int
ieee80211_ibss_setup_scan_channels(struct wiphy * wiphy,const struct cfg80211_chan_def * chandef,struct ieee80211_channel ** channels,unsigned int channels_max)1384 ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
1385 				   const struct cfg80211_chan_def *chandef,
1386 				   struct ieee80211_channel **channels,
1387 				   unsigned int channels_max)
1388 {
1389 	unsigned int n_chan = 0;
1390 	u32 width, cf1, cf2 = 0;
1391 
1392 	switch (chandef->width) {
1393 	case NL80211_CHAN_WIDTH_40:
1394 		width = 40;
1395 		break;
1396 	case NL80211_CHAN_WIDTH_80P80:
1397 		cf2 = chandef->center_freq2;
1398 		/* fall through */
1399 	case NL80211_CHAN_WIDTH_80:
1400 		width = 80;
1401 		break;
1402 	case NL80211_CHAN_WIDTH_160:
1403 		width = 160;
1404 		break;
1405 	default:
1406 		width = 20;
1407 		break;
1408 	}
1409 
1410 	cf1 = chandef->center_freq1;
1411 
1412 	n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
1413 
1414 	if (cf2)
1415 		n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
1416 					      channels_max - n_chan, cf2,
1417 					      width);
1418 
1419 	return n_chan;
1420 }
1421 
1422 /*
1423  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1424  */
1425 
ieee80211_sta_find_ibss(struct ieee80211_sub_if_data * sdata)1426 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1427 {
1428 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1429 	struct ieee80211_local *local = sdata->local;
1430 	struct cfg80211_bss *cbss;
1431 	struct ieee80211_channel *chan = NULL;
1432 	const u8 *bssid = NULL;
1433 	enum nl80211_bss_scan_width scan_width;
1434 	int active_ibss;
1435 
1436 	sdata_assert_lock(sdata);
1437 
1438 	active_ibss = ieee80211_sta_active_ibss(sdata);
1439 	ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1440 
1441 	if (active_ibss)
1442 		return;
1443 
1444 	if (ifibss->fixed_bssid)
1445 		bssid = ifibss->bssid;
1446 	if (ifibss->fixed_channel)
1447 		chan = ifibss->chandef.chan;
1448 	if (!is_zero_ether_addr(ifibss->bssid))
1449 		bssid = ifibss->bssid;
1450 	cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1451 				ifibss->ssid, ifibss->ssid_len,
1452 				IEEE80211_BSS_TYPE_IBSS,
1453 				IEEE80211_PRIVACY(ifibss->privacy));
1454 
1455 	if (cbss) {
1456 		struct ieee80211_bss *bss;
1457 
1458 		bss = (void *)cbss->priv;
1459 		ibss_dbg(sdata,
1460 			 "sta_find_ibss: selected %pM current %pM\n",
1461 			 cbss->bssid, ifibss->bssid);
1462 		sdata_info(sdata,
1463 			   "Selected IBSS BSSID %pM based on configured SSID\n",
1464 			   cbss->bssid);
1465 
1466 		ieee80211_sta_join_ibss(sdata, bss);
1467 		ieee80211_rx_bss_put(local, bss);
1468 		return;
1469 	}
1470 
1471 	/* if a fixed bssid and a fixed freq have been provided create the IBSS
1472 	 * directly and do not waste time scanning
1473 	 */
1474 	if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1475 		sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1476 			   bssid);
1477 		ieee80211_sta_create_ibss(sdata);
1478 		return;
1479 	}
1480 
1481 
1482 	ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1483 
1484 	/* Selected IBSS not found in current scan results - try to scan */
1485 	if (time_after(jiffies, ifibss->last_scan_completed +
1486 					IEEE80211_SCAN_INTERVAL)) {
1487 		struct ieee80211_channel *channels[8];
1488 		unsigned int num;
1489 
1490 		sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1491 
1492 		scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1493 
1494 		if (ifibss->fixed_channel) {
1495 			num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
1496 								 &ifibss->chandef,
1497 								 channels,
1498 								 ARRAY_SIZE(channels));
1499 			ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1500 						    ifibss->ssid_len, channels,
1501 						    num, scan_width);
1502 		} else {
1503 			ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1504 						    ifibss->ssid_len, NULL,
1505 						    0, scan_width);
1506 		}
1507 	} else {
1508 		int interval = IEEE80211_SCAN_INTERVAL;
1509 
1510 		if (time_after(jiffies, ifibss->ibss_join_req +
1511 			       IEEE80211_IBSS_JOIN_TIMEOUT))
1512 			ieee80211_sta_create_ibss(sdata);
1513 
1514 		mod_timer(&ifibss->timer,
1515 			  round_jiffies(jiffies + interval));
1516 	}
1517 }
1518 
ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data * sdata,struct sk_buff * req)1519 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1520 					struct sk_buff *req)
1521 {
1522 	struct ieee80211_mgmt *mgmt = (void *)req->data;
1523 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1524 	struct ieee80211_local *local = sdata->local;
1525 	int tx_last_beacon, len = req->len;
1526 	struct sk_buff *skb;
1527 	struct beacon_data *presp;
1528 	u8 *pos, *end;
1529 
1530 	sdata_assert_lock(sdata);
1531 
1532 	presp = rcu_dereference_protected(ifibss->presp,
1533 					  lockdep_is_held(&sdata->wdev.mtx));
1534 
1535 	if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1536 	    len < 24 + 2 || !presp)
1537 		return;
1538 
1539 	tx_last_beacon = drv_tx_last_beacon(local);
1540 
1541 	ibss_dbg(sdata,
1542 		 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1543 		 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1544 
1545 	if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1546 		return;
1547 
1548 	if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1549 	    !is_broadcast_ether_addr(mgmt->bssid))
1550 		return;
1551 
1552 	end = ((u8 *) mgmt) + len;
1553 	pos = mgmt->u.probe_req.variable;
1554 	if (pos[0] != WLAN_EID_SSID ||
1555 	    pos + 2 + pos[1] > end) {
1556 		ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1557 			 mgmt->sa);
1558 		return;
1559 	}
1560 	if (pos[1] != 0 &&
1561 	    (pos[1] != ifibss->ssid_len ||
1562 	     memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1563 		/* Ignore ProbeReq for foreign SSID */
1564 		return;
1565 	}
1566 
1567 	/* Reply with ProbeResp */
1568 	skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1569 	if (!skb)
1570 		return;
1571 
1572 	skb_reserve(skb, local->tx_headroom);
1573 	memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1574 
1575 	memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1576 	ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1577 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1578 
1579 	/* avoid excessive retries for probe request to wildcard SSIDs */
1580 	if (pos[1] == 0)
1581 		IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1582 
1583 	ieee80211_tx_skb(sdata, skb);
1584 }
1585 
1586 static
ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data * sdata,struct ieee80211_mgmt * mgmt,size_t len,struct ieee80211_rx_status * rx_status)1587 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1588 				    struct ieee80211_mgmt *mgmt, size_t len,
1589 				    struct ieee80211_rx_status *rx_status)
1590 {
1591 	size_t baselen;
1592 	struct ieee802_11_elems elems;
1593 
1594 	BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1595 		     offsetof(typeof(mgmt->u.beacon), variable));
1596 
1597 	/*
1598 	 * either beacon or probe_resp but the variable field is at the
1599 	 * same offset
1600 	 */
1601 	baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1602 	if (baselen > len)
1603 		return;
1604 
1605 	ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1606 			       false, &elems);
1607 
1608 	ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1609 }
1610 
ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb)1611 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1612 				   struct sk_buff *skb)
1613 {
1614 	struct ieee80211_rx_status *rx_status;
1615 	struct ieee80211_mgmt *mgmt;
1616 	u16 fc;
1617 	struct ieee802_11_elems elems;
1618 	int ies_len;
1619 
1620 	rx_status = IEEE80211_SKB_RXCB(skb);
1621 	mgmt = (struct ieee80211_mgmt *) skb->data;
1622 	fc = le16_to_cpu(mgmt->frame_control);
1623 
1624 	sdata_lock(sdata);
1625 
1626 	if (!sdata->u.ibss.ssid_len)
1627 		goto mgmt_out; /* not ready to merge yet */
1628 
1629 	switch (fc & IEEE80211_FCTL_STYPE) {
1630 	case IEEE80211_STYPE_PROBE_REQ:
1631 		ieee80211_rx_mgmt_probe_req(sdata, skb);
1632 		break;
1633 	case IEEE80211_STYPE_PROBE_RESP:
1634 	case IEEE80211_STYPE_BEACON:
1635 		ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1636 					       rx_status);
1637 		break;
1638 	case IEEE80211_STYPE_AUTH:
1639 		ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1640 		break;
1641 	case IEEE80211_STYPE_DEAUTH:
1642 		ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1643 		break;
1644 	case IEEE80211_STYPE_ACTION:
1645 		switch (mgmt->u.action.category) {
1646 		case WLAN_CATEGORY_SPECTRUM_MGMT:
1647 			ies_len = skb->len -
1648 				  offsetof(struct ieee80211_mgmt,
1649 					   u.action.u.chan_switch.variable);
1650 
1651 			if (ies_len < 0)
1652 				break;
1653 
1654 			ieee802_11_parse_elems(
1655 				mgmt->u.action.u.chan_switch.variable,
1656 				ies_len, true, &elems);
1657 
1658 			if (elems.parse_error)
1659 				break;
1660 
1661 			ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1662 							rx_status, &elems);
1663 			break;
1664 		}
1665 	}
1666 
1667  mgmt_out:
1668 	sdata_unlock(sdata);
1669 }
1670 
ieee80211_ibss_work(struct ieee80211_sub_if_data * sdata)1671 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1672 {
1673 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1674 	struct sta_info *sta;
1675 
1676 	sdata_lock(sdata);
1677 
1678 	/*
1679 	 * Work could be scheduled after scan or similar
1680 	 * when we aren't even joined (or trying) with a
1681 	 * network.
1682 	 */
1683 	if (!ifibss->ssid_len)
1684 		goto out;
1685 
1686 	spin_lock_bh(&ifibss->incomplete_lock);
1687 	while (!list_empty(&ifibss->incomplete_stations)) {
1688 		sta = list_first_entry(&ifibss->incomplete_stations,
1689 				       struct sta_info, list);
1690 		list_del(&sta->list);
1691 		spin_unlock_bh(&ifibss->incomplete_lock);
1692 
1693 		ieee80211_ibss_finish_sta(sta);
1694 		rcu_read_unlock();
1695 		spin_lock_bh(&ifibss->incomplete_lock);
1696 	}
1697 	spin_unlock_bh(&ifibss->incomplete_lock);
1698 
1699 	switch (ifibss->state) {
1700 	case IEEE80211_IBSS_MLME_SEARCH:
1701 		ieee80211_sta_find_ibss(sdata);
1702 		break;
1703 	case IEEE80211_IBSS_MLME_JOINED:
1704 		ieee80211_sta_merge_ibss(sdata);
1705 		break;
1706 	default:
1707 		WARN_ON(1);
1708 		break;
1709 	}
1710 
1711  out:
1712 	sdata_unlock(sdata);
1713 }
1714 
ieee80211_ibss_timer(unsigned long data)1715 static void ieee80211_ibss_timer(unsigned long data)
1716 {
1717 	struct ieee80211_sub_if_data *sdata =
1718 		(struct ieee80211_sub_if_data *) data;
1719 
1720 	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1721 }
1722 
ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data * sdata)1723 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1724 {
1725 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1726 
1727 	setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1728 		    (unsigned long) sdata);
1729 	INIT_LIST_HEAD(&ifibss->incomplete_stations);
1730 	spin_lock_init(&ifibss->incomplete_lock);
1731 	INIT_WORK(&ifibss->csa_connection_drop_work,
1732 		  ieee80211_csa_connection_drop_work);
1733 }
1734 
1735 /* scan finished notification */
ieee80211_ibss_notify_scan_completed(struct ieee80211_local * local)1736 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1737 {
1738 	struct ieee80211_sub_if_data *sdata;
1739 
1740 	mutex_lock(&local->iflist_mtx);
1741 	list_for_each_entry(sdata, &local->interfaces, list) {
1742 		if (!ieee80211_sdata_running(sdata))
1743 			continue;
1744 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1745 			continue;
1746 		sdata->u.ibss.last_scan_completed = jiffies;
1747 	}
1748 	mutex_unlock(&local->iflist_mtx);
1749 }
1750 
ieee80211_ibss_join(struct ieee80211_sub_if_data * sdata,struct cfg80211_ibss_params * params)1751 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1752 			struct cfg80211_ibss_params *params)
1753 {
1754 	u32 changed = 0;
1755 	u32 rate_flags;
1756 	struct ieee80211_supported_band *sband;
1757 	enum ieee80211_chanctx_mode chanmode;
1758 	struct ieee80211_local *local = sdata->local;
1759 	int radar_detect_width = 0;
1760 	int i;
1761 	int ret;
1762 
1763 	ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1764 					    &params->chandef,
1765 					    sdata->wdev.iftype);
1766 	if (ret < 0)
1767 		return ret;
1768 
1769 	if (ret > 0) {
1770 		if (!params->userspace_handles_dfs)
1771 			return -EINVAL;
1772 		radar_detect_width = BIT(params->chandef.width);
1773 	}
1774 
1775 	chanmode = (params->channel_fixed && !ret) ?
1776 		IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1777 
1778 	mutex_lock(&local->chanctx_mtx);
1779 	ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1780 					   radar_detect_width);
1781 	mutex_unlock(&local->chanctx_mtx);
1782 	if (ret < 0)
1783 		return ret;
1784 
1785 	if (params->bssid) {
1786 		memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1787 		sdata->u.ibss.fixed_bssid = true;
1788 	} else
1789 		sdata->u.ibss.fixed_bssid = false;
1790 
1791 	sdata->u.ibss.privacy = params->privacy;
1792 	sdata->u.ibss.control_port = params->control_port;
1793 	sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1794 	sdata->u.ibss.basic_rates = params->basic_rates;
1795 	sdata->u.ibss.last_scan_completed = jiffies;
1796 
1797 	/* fix basic_rates if channel does not support these rates */
1798 	rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1799 	sband = local->hw.wiphy->bands[params->chandef.chan->band];
1800 	for (i = 0; i < sband->n_bitrates; i++) {
1801 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1802 			sdata->u.ibss.basic_rates &= ~BIT(i);
1803 	}
1804 	memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1805 	       sizeof(params->mcast_rate));
1806 
1807 	sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1808 
1809 	sdata->u.ibss.chandef = params->chandef;
1810 	sdata->u.ibss.fixed_channel = params->channel_fixed;
1811 
1812 	if (params->ie) {
1813 		sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1814 					   GFP_KERNEL);
1815 		if (sdata->u.ibss.ie)
1816 			sdata->u.ibss.ie_len = params->ie_len;
1817 	}
1818 
1819 	sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1820 	sdata->u.ibss.ibss_join_req = jiffies;
1821 
1822 	memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1823 	sdata->u.ibss.ssid_len = params->ssid_len;
1824 
1825 	memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1826 	       sizeof(sdata->u.ibss.ht_capa));
1827 	memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1828 	       sizeof(sdata->u.ibss.ht_capa_mask));
1829 
1830 	/*
1831 	 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1832 	 * reserved, but an HT STA shall protect HT transmissions as though
1833 	 * the HT Protection field were set to non-HT mixed mode.
1834 	 *
1835 	 * In an IBSS, the RIFS Mode field of the HT Operation element is
1836 	 * also reserved, but an HT STA shall operate as though this field
1837 	 * were set to 1.
1838 	 */
1839 
1840 	sdata->vif.bss_conf.ht_operation_mode |=
1841 		  IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1842 		| IEEE80211_HT_PARAM_RIFS_MODE;
1843 
1844 	changed |= BSS_CHANGED_HT;
1845 	ieee80211_bss_info_change_notify(sdata, changed);
1846 
1847 	sdata->smps_mode = IEEE80211_SMPS_OFF;
1848 	sdata->needed_rx_chains = local->rx_chains;
1849 
1850 	ieee80211_queue_work(&local->hw, &sdata->work);
1851 
1852 	return 0;
1853 }
1854 
ieee80211_ibss_leave(struct ieee80211_sub_if_data * sdata)1855 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1856 {
1857 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1858 
1859 	ieee80211_ibss_disconnect(sdata);
1860 	ifibss->ssid_len = 0;
1861 	eth_zero_addr(ifibss->bssid);
1862 
1863 	/* remove beacon */
1864 	kfree(sdata->u.ibss.ie);
1865 
1866 	/* on the next join, re-program HT parameters */
1867 	memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1868 	memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1869 
1870 	synchronize_rcu();
1871 
1872 	skb_queue_purge(&sdata->skb_queue);
1873 
1874 	del_timer_sync(&sdata->u.ibss.timer);
1875 
1876 	return 0;
1877 }
1878