1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * IBSS mode implementation
4  * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
5  * Copyright 2004, Instant802 Networks, Inc.
6  * Copyright 2005, Devicescape Software, Inc.
7  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
8  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
9  * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
10  * Copyright 2013-2014  Intel Mobile Communications GmbH
11  * Copyright(c) 2016 Intel Deutschland GmbH
12  * Copyright(c) 2018-2022 Intel Corporation
13  */
14 
15 #include <linux/delay.h>
16 #include <linux/slab.h>
17 #include <linux/if_ether.h>
18 #include <linux/skbuff.h>
19 #include <linux/if_arp.h>
20 #include <linux/etherdevice.h>
21 #include <linux/rtnetlink.h>
22 #include <net/mac80211.h>
23 
24 #include "ieee80211_i.h"
25 #include "driver-ops.h"
26 #include "rate.h"
27 
28 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
29 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
30 
31 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
32 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
33 #define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
34 
35 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
36 
37 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)38 ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
39 			   const int beacon_int, const u32 basic_rates,
40 			   const u16 capability, u64 tsf,
41 			   struct cfg80211_chan_def *chandef,
42 			   bool *have_higher_than_11mbit,
43 			   struct cfg80211_csa_settings *csa_settings)
44 {
45 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
46 	struct ieee80211_local *local = sdata->local;
47 	int rates_n = 0, i, ri;
48 	struct ieee80211_mgmt *mgmt;
49 	u8 *pos;
50 	struct ieee80211_supported_band *sband;
51 	u32 rate_flags, rates = 0, rates_added = 0;
52 	struct beacon_data *presp;
53 	int frame_len;
54 	int shift;
55 
56 	/* Build IBSS probe response */
57 	frame_len = sizeof(struct ieee80211_hdr_3addr) +
58 		    12 /* struct ieee80211_mgmt.u.beacon */ +
59 		    2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
60 		    2 + 8 /* max Supported Rates */ +
61 		    3 /* max DS params */ +
62 		    4 /* IBSS params */ +
63 		    5 /* Channel Switch Announcement */ +
64 		    2 + (IEEE80211_MAX_SUPP_RATES - 8) +
65 		    2 + sizeof(struct ieee80211_ht_cap) +
66 		    2 + sizeof(struct ieee80211_ht_operation) +
67 		    2 + sizeof(struct ieee80211_vht_cap) +
68 		    2 + sizeof(struct ieee80211_vht_operation) +
69 		    ifibss->ie_len;
70 	presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
71 	if (!presp)
72 		return NULL;
73 
74 	presp->head = (void *)(presp + 1);
75 
76 	mgmt = (void *) presp->head;
77 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
78 					  IEEE80211_STYPE_PROBE_RESP);
79 	eth_broadcast_addr(mgmt->da);
80 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
81 	memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
82 	mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
83 	mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
84 	mgmt->u.beacon.capab_info = cpu_to_le16(capability);
85 
86 	pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
87 
88 	*pos++ = WLAN_EID_SSID;
89 	*pos++ = ifibss->ssid_len;
90 	memcpy(pos, ifibss->ssid, ifibss->ssid_len);
91 	pos += ifibss->ssid_len;
92 
93 	sband = local->hw.wiphy->bands[chandef->chan->band];
94 	rate_flags = ieee80211_chandef_rate_flags(chandef);
95 	shift = ieee80211_chandef_get_shift(chandef);
96 	rates_n = 0;
97 	if (have_higher_than_11mbit)
98 		*have_higher_than_11mbit = false;
99 
100 	for (i = 0; i < sband->n_bitrates; i++) {
101 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
102 			continue;
103 		if (sband->bitrates[i].bitrate > 110 &&
104 		    have_higher_than_11mbit)
105 			*have_higher_than_11mbit = true;
106 
107 		rates |= BIT(i);
108 		rates_n++;
109 	}
110 
111 	*pos++ = WLAN_EID_SUPP_RATES;
112 	*pos++ = min_t(int, 8, rates_n);
113 	for (ri = 0; ri < sband->n_bitrates; ri++) {
114 		int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
115 					5 * (1 << shift));
116 		u8 basic = 0;
117 		if (!(rates & BIT(ri)))
118 			continue;
119 
120 		if (basic_rates & BIT(ri))
121 			basic = 0x80;
122 		*pos++ = basic | (u8) rate;
123 		if (++rates_added == 8) {
124 			ri++; /* continue at next rate for EXT_SUPP_RATES */
125 			break;
126 		}
127 	}
128 
129 	if (sband->band == NL80211_BAND_2GHZ) {
130 		*pos++ = WLAN_EID_DS_PARAMS;
131 		*pos++ = 1;
132 		*pos++ = ieee80211_frequency_to_channel(
133 				chandef->chan->center_freq);
134 	}
135 
136 	*pos++ = WLAN_EID_IBSS_PARAMS;
137 	*pos++ = 2;
138 	/* FIX: set ATIM window based on scan results */
139 	*pos++ = 0;
140 	*pos++ = 0;
141 
142 	if (csa_settings) {
143 		*pos++ = WLAN_EID_CHANNEL_SWITCH;
144 		*pos++ = 3;
145 		*pos++ = csa_settings->block_tx ? 1 : 0;
146 		*pos++ = ieee80211_frequency_to_channel(
147 				csa_settings->chandef.chan->center_freq);
148 		presp->cntdwn_counter_offsets[0] = (pos - presp->head);
149 		*pos++ = csa_settings->count;
150 		presp->cntdwn_current_counter = csa_settings->count;
151 	}
152 
153 	/* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
154 	if (rates_n > 8) {
155 		*pos++ = WLAN_EID_EXT_SUPP_RATES;
156 		*pos++ = rates_n - 8;
157 		for (; ri < sband->n_bitrates; ri++) {
158 			int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
159 						5 * (1 << shift));
160 			u8 basic = 0;
161 			if (!(rates & BIT(ri)))
162 				continue;
163 
164 			if (basic_rates & BIT(ri))
165 				basic = 0x80;
166 			*pos++ = basic | (u8) rate;
167 		}
168 	}
169 
170 	if (ifibss->ie_len) {
171 		memcpy(pos, ifibss->ie, ifibss->ie_len);
172 		pos += ifibss->ie_len;
173 	}
174 
175 	/* add HT capability and information IEs */
176 	if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
177 	    chandef->width != NL80211_CHAN_WIDTH_5 &&
178 	    chandef->width != NL80211_CHAN_WIDTH_10 &&
179 	    sband->ht_cap.ht_supported) {
180 		struct ieee80211_sta_ht_cap ht_cap;
181 
182 		memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
183 		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
184 
185 		pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
186 		/*
187 		 * Note: According to 802.11n-2009 9.13.3.1, HT Protection
188 		 * field and RIFS Mode are reserved in IBSS mode, therefore
189 		 * keep them at 0
190 		 */
191 		pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
192 						 chandef, 0, false);
193 
194 		/* add VHT capability and information IEs */
195 		if (chandef->width != NL80211_CHAN_WIDTH_20 &&
196 		    chandef->width != NL80211_CHAN_WIDTH_40 &&
197 		    sband->vht_cap.vht_supported) {
198 			pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
199 							 sband->vht_cap.cap);
200 			pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
201 							  chandef);
202 		}
203 	}
204 
205 	if (local->hw.queues >= IEEE80211_NUM_ACS)
206 		pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
207 
208 	presp->head_len = pos - presp->head;
209 	if (WARN_ON(presp->head_len > frame_len))
210 		goto error;
211 
212 	return presp;
213 error:
214 	kfree(presp);
215 	return NULL;
216 }
217 
__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)218 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
219 				      const u8 *bssid, const int beacon_int,
220 				      struct cfg80211_chan_def *req_chandef,
221 				      const u32 basic_rates,
222 				      const u16 capability, u64 tsf,
223 				      bool creator)
224 {
225 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
226 	struct ieee80211_local *local = sdata->local;
227 	struct ieee80211_mgmt *mgmt;
228 	struct cfg80211_bss *bss;
229 	u32 bss_change;
230 	struct cfg80211_chan_def chandef;
231 	struct ieee80211_channel *chan;
232 	struct beacon_data *presp;
233 	struct cfg80211_inform_bss bss_meta = {};
234 	bool have_higher_than_11mbit;
235 	bool radar_required;
236 	int err;
237 
238 	sdata_assert_lock(sdata);
239 
240 	/* Reset own TSF to allow time synchronization work. */
241 	drv_reset_tsf(local, sdata);
242 
243 	if (!ether_addr_equal(ifibss->bssid, bssid))
244 		sta_info_flush(sdata);
245 
246 	/* if merging, indicate to driver that we leave the old IBSS */
247 	if (sdata->vif.cfg.ibss_joined) {
248 		sdata->vif.cfg.ibss_joined = false;
249 		sdata->vif.cfg.ibss_creator = false;
250 		sdata->vif.bss_conf.enable_beacon = false;
251 		netif_carrier_off(sdata->dev);
252 		ieee80211_bss_info_change_notify(sdata,
253 						 BSS_CHANGED_IBSS |
254 						 BSS_CHANGED_BEACON_ENABLED);
255 		drv_leave_ibss(local, sdata);
256 	}
257 
258 	presp = sdata_dereference(ifibss->presp, sdata);
259 	RCU_INIT_POINTER(ifibss->presp, NULL);
260 	if (presp)
261 		kfree_rcu(presp, rcu_head);
262 
263 	/* make a copy of the chandef, it could be modified below. */
264 	chandef = *req_chandef;
265 	chan = chandef.chan;
266 	if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
267 				     NL80211_IFTYPE_ADHOC)) {
268 		if (chandef.width == NL80211_CHAN_WIDTH_5 ||
269 		    chandef.width == NL80211_CHAN_WIDTH_10 ||
270 		    chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
271 		    chandef.width == NL80211_CHAN_WIDTH_20) {
272 			sdata_info(sdata,
273 				   "Failed to join IBSS, beacons forbidden\n");
274 			return;
275 		}
276 		chandef.width = NL80211_CHAN_WIDTH_20;
277 		chandef.center_freq1 = chan->center_freq;
278 		/* check again for downgraded chandef */
279 		if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
280 					     NL80211_IFTYPE_ADHOC)) {
281 			sdata_info(sdata,
282 				   "Failed to join IBSS, beacons forbidden\n");
283 			return;
284 		}
285 	}
286 
287 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
288 					    &chandef, NL80211_IFTYPE_ADHOC);
289 	if (err < 0) {
290 		sdata_info(sdata,
291 			   "Failed to join IBSS, invalid chandef\n");
292 		return;
293 	}
294 	if (err > 0 && !ifibss->userspace_handles_dfs) {
295 		sdata_info(sdata,
296 			   "Failed to join IBSS, DFS channel without control program\n");
297 		return;
298 	}
299 
300 	radar_required = err;
301 
302 	mutex_lock(&local->mtx);
303 	if (ieee80211_link_use_channel(&sdata->deflink, &chandef,
304 				       ifibss->fixed_channel ?
305 					IEEE80211_CHANCTX_SHARED :
306 					IEEE80211_CHANCTX_EXCLUSIVE)) {
307 		sdata_info(sdata, "Failed to join IBSS, no channel context\n");
308 		mutex_unlock(&local->mtx);
309 		return;
310 	}
311 	sdata->deflink.radar_required = radar_required;
312 	mutex_unlock(&local->mtx);
313 
314 	memcpy(ifibss->bssid, bssid, ETH_ALEN);
315 
316 	presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
317 					   capability, tsf, &chandef,
318 					   &have_higher_than_11mbit, NULL);
319 	if (!presp)
320 		return;
321 
322 	rcu_assign_pointer(ifibss->presp, presp);
323 	mgmt = (void *)presp->head;
324 
325 	sdata->vif.bss_conf.enable_beacon = true;
326 	sdata->vif.bss_conf.beacon_int = beacon_int;
327 	sdata->vif.bss_conf.basic_rates = basic_rates;
328 	sdata->vif.cfg.ssid_len = ifibss->ssid_len;
329 	memcpy(sdata->vif.cfg.ssid, ifibss->ssid, ifibss->ssid_len);
330 	bss_change = BSS_CHANGED_BEACON_INT;
331 	bss_change |= ieee80211_reset_erp_info(sdata);
332 	bss_change |= BSS_CHANGED_BSSID;
333 	bss_change |= BSS_CHANGED_BEACON;
334 	bss_change |= BSS_CHANGED_BEACON_ENABLED;
335 	bss_change |= BSS_CHANGED_BASIC_RATES;
336 	bss_change |= BSS_CHANGED_HT;
337 	bss_change |= BSS_CHANGED_IBSS;
338 	bss_change |= BSS_CHANGED_SSID;
339 
340 	/*
341 	 * In 5 GHz/802.11a, we can always use short slot time.
342 	 * (IEEE 802.11-2012 18.3.8.7)
343 	 *
344 	 * In 2.4GHz, we must always use long slots in IBSS for compatibility
345 	 * reasons.
346 	 * (IEEE 802.11-2012 19.4.5)
347 	 *
348 	 * HT follows these specifications (IEEE 802.11-2012 20.3.18)
349 	 */
350 	sdata->vif.bss_conf.use_short_slot = chan->band == NL80211_BAND_5GHZ;
351 	bss_change |= BSS_CHANGED_ERP_SLOT;
352 
353 	/* cf. IEEE 802.11 9.2.12 */
354 	sdata->deflink.operating_11g_mode =
355 		chan->band == NL80211_BAND_2GHZ && have_higher_than_11mbit;
356 
357 	ieee80211_set_wmm_default(&sdata->deflink, true, false);
358 
359 	sdata->vif.cfg.ibss_joined = true;
360 	sdata->vif.cfg.ibss_creator = creator;
361 
362 	err = drv_join_ibss(local, sdata);
363 	if (err) {
364 		sdata->vif.cfg.ibss_joined = false;
365 		sdata->vif.cfg.ibss_creator = false;
366 		sdata->vif.bss_conf.enable_beacon = false;
367 		sdata->vif.cfg.ssid_len = 0;
368 		RCU_INIT_POINTER(ifibss->presp, NULL);
369 		kfree_rcu(presp, rcu_head);
370 		mutex_lock(&local->mtx);
371 		ieee80211_link_release_channel(&sdata->deflink);
372 		mutex_unlock(&local->mtx);
373 		sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
374 			   err);
375 		return;
376 	}
377 
378 	ieee80211_bss_info_change_notify(sdata, bss_change);
379 
380 	ifibss->state = IEEE80211_IBSS_MLME_JOINED;
381 	mod_timer(&ifibss->timer,
382 		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
383 
384 	bss_meta.chan = chan;
385 	bss_meta.scan_width = cfg80211_chandef_to_scan_width(&chandef);
386 	bss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, mgmt,
387 					     presp->head_len, GFP_KERNEL);
388 
389 	cfg80211_put_bss(local->hw.wiphy, bss);
390 	netif_carrier_on(sdata->dev);
391 	cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
392 }
393 
ieee80211_sta_join_ibss(struct ieee80211_sub_if_data * sdata,struct ieee80211_bss * bss)394 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
395 				    struct ieee80211_bss *bss)
396 {
397 	struct cfg80211_bss *cbss =
398 		container_of((void *)bss, struct cfg80211_bss, priv);
399 	struct ieee80211_supported_band *sband;
400 	struct cfg80211_chan_def chandef;
401 	u32 basic_rates;
402 	int i, j;
403 	u16 beacon_int = cbss->beacon_interval;
404 	const struct cfg80211_bss_ies *ies;
405 	enum nl80211_channel_type chan_type;
406 	u64 tsf;
407 	u32 rate_flags;
408 	int shift;
409 
410 	sdata_assert_lock(sdata);
411 
412 	if (beacon_int < 10)
413 		beacon_int = 10;
414 
415 	switch (sdata->u.ibss.chandef.width) {
416 	case NL80211_CHAN_WIDTH_20_NOHT:
417 	case NL80211_CHAN_WIDTH_20:
418 	case NL80211_CHAN_WIDTH_40:
419 		chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
420 		cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
421 		break;
422 	case NL80211_CHAN_WIDTH_5:
423 	case NL80211_CHAN_WIDTH_10:
424 		cfg80211_chandef_create(&chandef, cbss->channel,
425 					NL80211_CHAN_NO_HT);
426 		chandef.width = sdata->u.ibss.chandef.width;
427 		break;
428 	case NL80211_CHAN_WIDTH_80:
429 	case NL80211_CHAN_WIDTH_80P80:
430 	case NL80211_CHAN_WIDTH_160:
431 		chandef = sdata->u.ibss.chandef;
432 		chandef.chan = cbss->channel;
433 		break;
434 	default:
435 		/* fall back to 20 MHz for unsupported modes */
436 		cfg80211_chandef_create(&chandef, cbss->channel,
437 					NL80211_CHAN_NO_HT);
438 		break;
439 	}
440 
441 	sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
442 	rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
443 	shift = ieee80211_vif_get_shift(&sdata->vif);
444 
445 	basic_rates = 0;
446 
447 	for (i = 0; i < bss->supp_rates_len; i++) {
448 		int rate = bss->supp_rates[i] & 0x7f;
449 		bool is_basic = !!(bss->supp_rates[i] & 0x80);
450 
451 		for (j = 0; j < sband->n_bitrates; j++) {
452 			int brate;
453 			if ((rate_flags & sband->bitrates[j].flags)
454 			    != rate_flags)
455 				continue;
456 
457 			brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
458 					     5 * (1 << shift));
459 			if (brate == rate) {
460 				if (is_basic)
461 					basic_rates |= BIT(j);
462 				break;
463 			}
464 		}
465 	}
466 
467 	rcu_read_lock();
468 	ies = rcu_dereference(cbss->ies);
469 	tsf = ies->tsf;
470 	rcu_read_unlock();
471 
472 	__ieee80211_sta_join_ibss(sdata, cbss->bssid,
473 				  beacon_int,
474 				  &chandef,
475 				  basic_rates,
476 				  cbss->capability,
477 				  tsf, false);
478 }
479 
ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data * sdata,struct cfg80211_csa_settings * csa_settings)480 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
481 			      struct cfg80211_csa_settings *csa_settings)
482 {
483 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
484 	struct beacon_data *presp, *old_presp;
485 	struct cfg80211_bss *cbss;
486 	const struct cfg80211_bss_ies *ies;
487 	u16 capability = WLAN_CAPABILITY_IBSS;
488 	u64 tsf;
489 
490 	sdata_assert_lock(sdata);
491 
492 	if (ifibss->privacy)
493 		capability |= WLAN_CAPABILITY_PRIVACY;
494 
495 	cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
496 				ifibss->bssid, ifibss->ssid,
497 				ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS,
498 				IEEE80211_PRIVACY(ifibss->privacy));
499 
500 	if (WARN_ON(!cbss))
501 		return -EINVAL;
502 
503 	rcu_read_lock();
504 	ies = rcu_dereference(cbss->ies);
505 	tsf = ies->tsf;
506 	rcu_read_unlock();
507 	cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
508 
509 	old_presp = sdata_dereference(ifibss->presp, sdata);
510 
511 	presp = ieee80211_ibss_build_presp(sdata,
512 					   sdata->vif.bss_conf.beacon_int,
513 					   sdata->vif.bss_conf.basic_rates,
514 					   capability, tsf, &ifibss->chandef,
515 					   NULL, csa_settings);
516 	if (!presp)
517 		return -ENOMEM;
518 
519 	rcu_assign_pointer(ifibss->presp, presp);
520 	if (old_presp)
521 		kfree_rcu(old_presp, rcu_head);
522 
523 	return BSS_CHANGED_BEACON;
524 }
525 
ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data * sdata)526 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
527 {
528 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
529 	struct cfg80211_bss *cbss;
530 
531 	sdata_assert_lock(sdata);
532 
533 	/* When not connected/joined, sending CSA doesn't make sense. */
534 	if (ifibss->state != IEEE80211_IBSS_MLME_JOINED)
535 		return -ENOLINK;
536 
537 	/* update cfg80211 bss information with the new channel */
538 	if (!is_zero_ether_addr(ifibss->bssid)) {
539 		cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
540 					ifibss->chandef.chan,
541 					ifibss->bssid, ifibss->ssid,
542 					ifibss->ssid_len,
543 					IEEE80211_BSS_TYPE_IBSS,
544 					IEEE80211_PRIVACY(ifibss->privacy));
545 		/* XXX: should not really modify cfg80211 data */
546 		if (cbss) {
547 			cbss->channel = sdata->deflink.csa_chandef.chan;
548 			cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
549 		}
550 	}
551 
552 	ifibss->chandef = sdata->deflink.csa_chandef;
553 
554 	/* generate the beacon */
555 	return ieee80211_ibss_csa_beacon(sdata, NULL);
556 }
557 
ieee80211_ibss_stop(struct ieee80211_sub_if_data * sdata)558 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
559 {
560 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
561 
562 	cancel_work_sync(&ifibss->csa_connection_drop_work);
563 }
564 
ieee80211_ibss_finish_sta(struct sta_info * sta)565 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
566 	__acquires(RCU)
567 {
568 	struct ieee80211_sub_if_data *sdata = sta->sdata;
569 	u8 addr[ETH_ALEN];
570 
571 	memcpy(addr, sta->sta.addr, ETH_ALEN);
572 
573 	ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
574 
575 	sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
576 	sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
577 	/* authorize the station only if the network is not RSN protected. If
578 	 * not wait for the userspace to authorize it */
579 	if (!sta->sdata->u.ibss.control_port)
580 		sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
581 
582 	rate_control_rate_init(sta);
583 
584 	/* If it fails, maybe we raced another insertion? */
585 	if (sta_info_insert_rcu(sta))
586 		return sta_info_get(sdata, addr);
587 	return sta;
588 }
589 
590 static struct sta_info *
ieee80211_ibss_add_sta(struct ieee80211_sub_if_data * sdata,const u8 * bssid,const u8 * addr,u32 supp_rates)591 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
592 		       const u8 *addr, u32 supp_rates)
593 	__acquires(RCU)
594 {
595 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
596 	struct ieee80211_local *local = sdata->local;
597 	struct sta_info *sta;
598 	struct ieee80211_chanctx_conf *chanctx_conf;
599 	struct ieee80211_supported_band *sband;
600 	enum nl80211_bss_scan_width scan_width;
601 	int band;
602 
603 	/*
604 	 * XXX: Consider removing the least recently used entry and
605 	 * 	allow new one to be added.
606 	 */
607 	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
608 		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
609 				    sdata->name, addr);
610 		rcu_read_lock();
611 		return NULL;
612 	}
613 
614 	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
615 		rcu_read_lock();
616 		return NULL;
617 	}
618 
619 	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
620 		rcu_read_lock();
621 		return NULL;
622 	}
623 
624 	rcu_read_lock();
625 	chanctx_conf = rcu_dereference(sdata->vif.bss_conf.chanctx_conf);
626 	if (WARN_ON_ONCE(!chanctx_conf))
627 		return NULL;
628 	band = chanctx_conf->def.chan->band;
629 	scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
630 	rcu_read_unlock();
631 
632 	sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
633 	if (!sta) {
634 		rcu_read_lock();
635 		return NULL;
636 	}
637 
638 	/* make sure mandatory rates are always added */
639 	sband = local->hw.wiphy->bands[band];
640 	sta->sta.deflink.supp_rates[band] = supp_rates |
641 			ieee80211_mandatory_rates(sband, scan_width);
642 
643 	return ieee80211_ibss_finish_sta(sta);
644 }
645 
ieee80211_sta_active_ibss(struct ieee80211_sub_if_data * sdata)646 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
647 {
648 	struct ieee80211_local *local = sdata->local;
649 	int active = 0;
650 	struct sta_info *sta;
651 
652 	sdata_assert_lock(sdata);
653 
654 	rcu_read_lock();
655 
656 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
657 		unsigned long last_active = ieee80211_sta_last_active(sta);
658 
659 		if (sta->sdata == sdata &&
660 		    time_is_after_jiffies(last_active +
661 					  IEEE80211_IBSS_MERGE_INTERVAL)) {
662 			active++;
663 			break;
664 		}
665 	}
666 
667 	rcu_read_unlock();
668 
669 	return active;
670 }
671 
ieee80211_ibss_disconnect(struct ieee80211_sub_if_data * sdata)672 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
673 {
674 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
675 	struct ieee80211_local *local = sdata->local;
676 	struct cfg80211_bss *cbss;
677 	struct beacon_data *presp;
678 	struct sta_info *sta;
679 
680 	if (!is_zero_ether_addr(ifibss->bssid)) {
681 		cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
682 					ifibss->bssid, ifibss->ssid,
683 					ifibss->ssid_len,
684 					IEEE80211_BSS_TYPE_IBSS,
685 					IEEE80211_PRIVACY(ifibss->privacy));
686 
687 		if (cbss) {
688 			cfg80211_unlink_bss(local->hw.wiphy, cbss);
689 			cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
690 		}
691 	}
692 
693 	ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
694 
695 	sta_info_flush(sdata);
696 
697 	spin_lock_bh(&ifibss->incomplete_lock);
698 	while (!list_empty(&ifibss->incomplete_stations)) {
699 		sta = list_first_entry(&ifibss->incomplete_stations,
700 				       struct sta_info, list);
701 		list_del(&sta->list);
702 		spin_unlock_bh(&ifibss->incomplete_lock);
703 
704 		sta_info_free(local, sta);
705 		spin_lock_bh(&ifibss->incomplete_lock);
706 	}
707 	spin_unlock_bh(&ifibss->incomplete_lock);
708 
709 	netif_carrier_off(sdata->dev);
710 
711 	sdata->vif.cfg.ibss_joined = false;
712 	sdata->vif.cfg.ibss_creator = false;
713 	sdata->vif.bss_conf.enable_beacon = false;
714 	sdata->vif.cfg.ssid_len = 0;
715 
716 	/* remove beacon */
717 	presp = sdata_dereference(ifibss->presp, sdata);
718 	RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
719 	if (presp)
720 		kfree_rcu(presp, rcu_head);
721 
722 	clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
723 	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
724 						BSS_CHANGED_IBSS);
725 	drv_leave_ibss(local, sdata);
726 	mutex_lock(&local->mtx);
727 	ieee80211_link_release_channel(&sdata->deflink);
728 	mutex_unlock(&local->mtx);
729 }
730 
ieee80211_csa_connection_drop_work(struct work_struct * work)731 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
732 {
733 	struct ieee80211_sub_if_data *sdata =
734 		container_of(work, struct ieee80211_sub_if_data,
735 			     u.ibss.csa_connection_drop_work);
736 
737 	sdata_lock(sdata);
738 
739 	ieee80211_ibss_disconnect(sdata);
740 	synchronize_rcu();
741 	skb_queue_purge(&sdata->skb_queue);
742 
743 	/* trigger a scan to find another IBSS network to join */
744 	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
745 
746 	sdata_unlock(sdata);
747 }
748 
ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data * sdata)749 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
750 {
751 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
752 	int err;
753 
754 	/* if the current channel is a DFS channel, mark the channel as
755 	 * unavailable.
756 	 */
757 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
758 					    &ifibss->chandef,
759 					    NL80211_IFTYPE_ADHOC);
760 	if (err > 0)
761 		cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
762 				     GFP_ATOMIC);
763 }
764 
765 static bool
ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data * sdata,struct ieee802_11_elems * elems,bool beacon)766 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
767 				  struct ieee802_11_elems *elems,
768 				  bool beacon)
769 {
770 	struct cfg80211_csa_settings params;
771 	struct ieee80211_csa_ie csa_ie;
772 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
773 	enum nl80211_channel_type ch_type;
774 	int err;
775 	ieee80211_conn_flags_t conn_flags;
776 	u32 vht_cap_info = 0;
777 
778 	sdata_assert_lock(sdata);
779 
780 	conn_flags = IEEE80211_CONN_DISABLE_VHT;
781 
782 	switch (ifibss->chandef.width) {
783 	case NL80211_CHAN_WIDTH_5:
784 	case NL80211_CHAN_WIDTH_10:
785 	case NL80211_CHAN_WIDTH_20_NOHT:
786 		conn_flags |= IEEE80211_CONN_DISABLE_HT;
787 		fallthrough;
788 	case NL80211_CHAN_WIDTH_20:
789 		conn_flags |= IEEE80211_CONN_DISABLE_40MHZ;
790 		break;
791 	default:
792 		break;
793 	}
794 
795 	if (elems->vht_cap_elem)
796 		vht_cap_info = le32_to_cpu(elems->vht_cap_elem->vht_cap_info);
797 
798 	memset(&params, 0, sizeof(params));
799 	err = ieee80211_parse_ch_switch_ie(sdata, elems,
800 					   ifibss->chandef.chan->band,
801 					   vht_cap_info,
802 					   conn_flags, ifibss->bssid, &csa_ie);
803 	/* can't switch to destination channel, fail */
804 	if (err < 0)
805 		goto disconnect;
806 
807 	/* did not contain a CSA */
808 	if (err)
809 		return false;
810 
811 	/* channel switch is not supported, disconnect */
812 	if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
813 		goto disconnect;
814 
815 	params.count = csa_ie.count;
816 	params.chandef = csa_ie.chandef;
817 
818 	switch (ifibss->chandef.width) {
819 	case NL80211_CHAN_WIDTH_20_NOHT:
820 	case NL80211_CHAN_WIDTH_20:
821 	case NL80211_CHAN_WIDTH_40:
822 		/* keep our current HT mode (HT20/HT40+/HT40-), even if
823 		 * another mode  has been announced. The mode is not adopted
824 		 * within the beacon while doing CSA and we should therefore
825 		 * keep the mode which we announce.
826 		 */
827 		ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
828 		cfg80211_chandef_create(&params.chandef, params.chandef.chan,
829 					ch_type);
830 		break;
831 	case NL80211_CHAN_WIDTH_5:
832 	case NL80211_CHAN_WIDTH_10:
833 		if (params.chandef.width != ifibss->chandef.width) {
834 			sdata_info(sdata,
835 				   "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
836 				   ifibss->bssid,
837 				   params.chandef.chan->center_freq,
838 				   params.chandef.width,
839 				   params.chandef.center_freq1,
840 				   params.chandef.center_freq2);
841 			goto disconnect;
842 		}
843 		break;
844 	default:
845 		/* should not happen, conn_flags should prevent VHT modes. */
846 		WARN_ON(1);
847 		goto disconnect;
848 	}
849 
850 	if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
851 				     NL80211_IFTYPE_ADHOC)) {
852 		sdata_info(sdata,
853 			   "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
854 			   ifibss->bssid,
855 			   params.chandef.chan->center_freq,
856 			   params.chandef.width,
857 			   params.chandef.center_freq1,
858 			   params.chandef.center_freq2);
859 		goto disconnect;
860 	}
861 
862 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
863 					    &params.chandef,
864 					    NL80211_IFTYPE_ADHOC);
865 	if (err < 0)
866 		goto disconnect;
867 	if (err > 0 && !ifibss->userspace_handles_dfs) {
868 		/* IBSS-DFS only allowed with a control program */
869 		goto disconnect;
870 	}
871 
872 	params.radar_required = err;
873 
874 	if (cfg80211_chandef_identical(&params.chandef,
875 				       &sdata->vif.bss_conf.chandef)) {
876 		ibss_dbg(sdata,
877 			 "received csa with an identical chandef, ignoring\n");
878 		return true;
879 	}
880 
881 	/* all checks done, now perform the channel switch. */
882 	ibss_dbg(sdata,
883 		 "received channel switch announcement to go to channel %d MHz\n",
884 		 params.chandef.chan->center_freq);
885 
886 	params.block_tx = !!csa_ie.mode;
887 
888 	if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
889 				     &params))
890 		goto disconnect;
891 
892 	ieee80211_ibss_csa_mark_radar(sdata);
893 
894 	return true;
895 disconnect:
896 	ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
897 	ieee80211_queue_work(&sdata->local->hw,
898 			     &ifibss->csa_connection_drop_work);
899 
900 	ieee80211_ibss_csa_mark_radar(sdata);
901 
902 	return true;
903 }
904 
905 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)906 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
907 				struct ieee80211_mgmt *mgmt, size_t len,
908 				struct ieee80211_rx_status *rx_status,
909 				struct ieee802_11_elems *elems)
910 {
911 	int required_len;
912 
913 	if (len < IEEE80211_MIN_ACTION_SIZE + 1)
914 		return;
915 
916 	/* CSA is the only action we handle for now */
917 	if (mgmt->u.action.u.measurement.action_code !=
918 	    WLAN_ACTION_SPCT_CHL_SWITCH)
919 		return;
920 
921 	required_len = IEEE80211_MIN_ACTION_SIZE +
922 		       sizeof(mgmt->u.action.u.chan_switch);
923 	if (len < required_len)
924 		return;
925 
926 	if (!sdata->vif.bss_conf.csa_active)
927 		ieee80211_ibss_process_chanswitch(sdata, elems, false);
928 }
929 
ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data * sdata,struct ieee80211_mgmt * mgmt,size_t len)930 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
931 					  struct ieee80211_mgmt *mgmt,
932 					  size_t len)
933 {
934 	u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
935 
936 	if (len < IEEE80211_DEAUTH_FRAME_LEN)
937 		return;
938 
939 	ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
940 	ibss_dbg(sdata, "\tBSSID=%pM (reason: %d)\n", mgmt->bssid, reason);
941 	sta_info_destroy_addr(sdata, mgmt->sa);
942 }
943 
ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data * sdata,struct ieee80211_mgmt * mgmt,size_t len)944 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
945 					struct ieee80211_mgmt *mgmt,
946 					size_t len)
947 {
948 	u16 auth_alg, auth_transaction;
949 
950 	sdata_assert_lock(sdata);
951 
952 	if (len < 24 + 6)
953 		return;
954 
955 	auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
956 	auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
957 
958 	ibss_dbg(sdata, "RX Auth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
959 	ibss_dbg(sdata, "\tBSSID=%pM (auth_transaction=%d)\n",
960 		 mgmt->bssid, auth_transaction);
961 
962 	if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
963 		return;
964 
965 	/*
966 	 * IEEE 802.11 standard does not require authentication in IBSS
967 	 * networks and most implementations do not seem to use it.
968 	 * However, try to reply to authentication attempts if someone
969 	 * has actually implemented this.
970 	 */
971 	ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
972 			    mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
973 }
974 
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)975 static void ieee80211_update_sta_info(struct ieee80211_sub_if_data *sdata,
976 				      struct ieee80211_mgmt *mgmt, size_t len,
977 				      struct ieee80211_rx_status *rx_status,
978 				      struct ieee802_11_elems *elems,
979 				      struct ieee80211_channel *channel)
980 {
981 	struct sta_info *sta;
982 	enum nl80211_band band = rx_status->band;
983 	enum nl80211_bss_scan_width scan_width;
984 	struct ieee80211_local *local = sdata->local;
985 	struct ieee80211_supported_band *sband;
986 	bool rates_updated = false;
987 	u32 supp_rates = 0;
988 
989 	if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
990 		return;
991 
992 	if (!ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid))
993 		return;
994 
995 	sband = local->hw.wiphy->bands[band];
996 	if (WARN_ON(!sband))
997 		return;
998 
999 	rcu_read_lock();
1000 	sta = sta_info_get(sdata, mgmt->sa);
1001 
1002 	if (elems->supp_rates) {
1003 		supp_rates = ieee80211_sta_get_rates(sdata, elems,
1004 						     band, NULL);
1005 		if (sta) {
1006 			u32 prev_rates;
1007 
1008 			prev_rates = sta->sta.deflink.supp_rates[band];
1009 			/* make sure mandatory rates are always added */
1010 			scan_width = NL80211_BSS_CHAN_WIDTH_20;
1011 			if (rx_status->bw == RATE_INFO_BW_5)
1012 				scan_width = NL80211_BSS_CHAN_WIDTH_5;
1013 			else if (rx_status->bw == RATE_INFO_BW_10)
1014 				scan_width = NL80211_BSS_CHAN_WIDTH_10;
1015 
1016 			sta->sta.deflink.supp_rates[band] = supp_rates |
1017 				ieee80211_mandatory_rates(sband, scan_width);
1018 			if (sta->sta.deflink.supp_rates[band] != prev_rates) {
1019 				ibss_dbg(sdata,
1020 					 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1021 					 sta->sta.addr, prev_rates,
1022 					 sta->sta.deflink.supp_rates[band]);
1023 				rates_updated = true;
1024 			}
1025 		} else {
1026 			rcu_read_unlock();
1027 			sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1028 						     mgmt->sa, supp_rates);
1029 		}
1030 	}
1031 
1032 	if (sta && !sta->sta.wme &&
1033 	    (elems->wmm_info || elems->s1g_capab) &&
1034 	    local->hw.queues >= IEEE80211_NUM_ACS) {
1035 		sta->sta.wme = true;
1036 		ieee80211_check_fast_xmit(sta);
1037 	}
1038 
1039 	if (sta && elems->ht_operation && elems->ht_cap_elem &&
1040 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1041 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1042 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1043 		/* we both use HT */
1044 		struct ieee80211_ht_cap htcap_ie;
1045 		struct cfg80211_chan_def chandef;
1046 		enum ieee80211_sta_rx_bandwidth bw = sta->sta.deflink.bandwidth;
1047 
1048 		cfg80211_chandef_create(&chandef, channel, NL80211_CHAN_NO_HT);
1049 		ieee80211_chandef_ht_oper(elems->ht_operation, &chandef);
1050 
1051 		memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1052 		rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
1053 								   &htcap_ie,
1054 								   &sta->deflink);
1055 
1056 		if (elems->vht_operation && elems->vht_cap_elem &&
1057 		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20 &&
1058 		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_40) {
1059 			/* we both use VHT */
1060 			struct ieee80211_vht_cap cap_ie;
1061 			struct ieee80211_sta_vht_cap cap = sta->sta.deflink.vht_cap;
1062 			u32 vht_cap_info =
1063 				le32_to_cpu(elems->vht_cap_elem->vht_cap_info);
1064 
1065 			ieee80211_chandef_vht_oper(&local->hw, vht_cap_info,
1066 						   elems->vht_operation,
1067 						   elems->ht_operation,
1068 						   &chandef);
1069 			memcpy(&cap_ie, elems->vht_cap_elem, sizeof(cap_ie));
1070 			ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
1071 							    &cap_ie,
1072 							    &sta->deflink);
1073 			if (memcmp(&cap, &sta->sta.deflink.vht_cap, sizeof(cap)))
1074 				rates_updated |= true;
1075 		}
1076 
1077 		if (bw != sta->sta.deflink.bandwidth)
1078 			rates_updated |= true;
1079 
1080 		if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
1081 						 &chandef))
1082 			WARN_ON_ONCE(1);
1083 	}
1084 
1085 	if (sta && rates_updated) {
1086 		u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
1087 		u8 rx_nss = sta->sta.deflink.rx_nss;
1088 
1089 		/* Force rx_nss recalculation */
1090 		sta->sta.deflink.rx_nss = 0;
1091 		rate_control_rate_init(sta);
1092 		if (sta->sta.deflink.rx_nss != rx_nss)
1093 			changed |= IEEE80211_RC_NSS_CHANGED;
1094 
1095 		drv_sta_rc_update(local, sdata, &sta->sta, changed);
1096 	}
1097 
1098 	rcu_read_unlock();
1099 }
1100 
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)1101 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1102 				  struct ieee80211_mgmt *mgmt, size_t len,
1103 				  struct ieee80211_rx_status *rx_status,
1104 				  struct ieee802_11_elems *elems)
1105 {
1106 	struct ieee80211_local *local = sdata->local;
1107 	struct cfg80211_bss *cbss;
1108 	struct ieee80211_bss *bss;
1109 	struct ieee80211_channel *channel;
1110 	u64 beacon_timestamp, rx_timestamp;
1111 	u32 supp_rates = 0;
1112 	enum nl80211_band band = rx_status->band;
1113 
1114 	channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1115 	if (!channel)
1116 		return;
1117 
1118 	ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
1119 
1120 	bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, channel);
1121 	if (!bss)
1122 		return;
1123 
1124 	cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1125 
1126 	/* same for beacon and probe response */
1127 	beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1128 
1129 	/* check if we need to merge IBSS */
1130 
1131 	/* not an IBSS */
1132 	if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1133 		goto put_bss;
1134 
1135 	/* different channel */
1136 	if (sdata->u.ibss.fixed_channel &&
1137 	    sdata->u.ibss.chandef.chan != cbss->channel)
1138 		goto put_bss;
1139 
1140 	/* different SSID */
1141 	if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1142 	    memcmp(elems->ssid, sdata->u.ibss.ssid,
1143 				sdata->u.ibss.ssid_len))
1144 		goto put_bss;
1145 
1146 	/* process channel switch */
1147 	if (sdata->vif.bss_conf.csa_active ||
1148 	    ieee80211_ibss_process_chanswitch(sdata, elems, true))
1149 		goto put_bss;
1150 
1151 	/* same BSSID */
1152 	if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1153 		goto put_bss;
1154 
1155 	/* we use a fixed BSSID */
1156 	if (sdata->u.ibss.fixed_bssid)
1157 		goto put_bss;
1158 
1159 	if (ieee80211_have_rx_timestamp(rx_status)) {
1160 		/* time when timestamp field was received */
1161 		rx_timestamp =
1162 			ieee80211_calculate_rx_timestamp(local, rx_status,
1163 							 len + FCS_LEN, 24);
1164 	} else {
1165 		/*
1166 		 * second best option: get current TSF
1167 		 * (will return -1 if not supported)
1168 		 */
1169 		rx_timestamp = drv_get_tsf(local, sdata);
1170 	}
1171 
1172 	ibss_dbg(sdata, "RX beacon SA=%pM BSSID=%pM TSF=0x%llx\n",
1173 		 mgmt->sa, mgmt->bssid,
1174 		 (unsigned long long)rx_timestamp);
1175 	ibss_dbg(sdata, "\tBCN=0x%llx diff=%lld @%lu\n",
1176 		 (unsigned long long)beacon_timestamp,
1177 		 (unsigned long long)(rx_timestamp - beacon_timestamp),
1178 		 jiffies);
1179 
1180 	if (beacon_timestamp > rx_timestamp) {
1181 		ibss_dbg(sdata,
1182 			 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1183 			 mgmt->bssid);
1184 		ieee80211_sta_join_ibss(sdata, bss);
1185 		supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1186 		ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1187 				       supp_rates);
1188 		rcu_read_unlock();
1189 	}
1190 
1191  put_bss:
1192 	ieee80211_rx_bss_put(local, bss);
1193 }
1194 
ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data * sdata,const u8 * bssid,const u8 * addr,u32 supp_rates)1195 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1196 			      const u8 *bssid, const u8 *addr,
1197 			      u32 supp_rates)
1198 {
1199 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1200 	struct ieee80211_local *local = sdata->local;
1201 	struct sta_info *sta;
1202 	struct ieee80211_chanctx_conf *chanctx_conf;
1203 	struct ieee80211_supported_band *sband;
1204 	enum nl80211_bss_scan_width scan_width;
1205 	int band;
1206 
1207 	/*
1208 	 * XXX: Consider removing the least recently used entry and
1209 	 * 	allow new one to be added.
1210 	 */
1211 	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1212 		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1213 				    sdata->name, addr);
1214 		return;
1215 	}
1216 
1217 	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1218 		return;
1219 
1220 	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1221 		return;
1222 
1223 	rcu_read_lock();
1224 	chanctx_conf = rcu_dereference(sdata->vif.bss_conf.chanctx_conf);
1225 	if (WARN_ON_ONCE(!chanctx_conf)) {
1226 		rcu_read_unlock();
1227 		return;
1228 	}
1229 	band = chanctx_conf->def.chan->band;
1230 	scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1231 	rcu_read_unlock();
1232 
1233 	sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1234 	if (!sta)
1235 		return;
1236 
1237 	/* make sure mandatory rates are always added */
1238 	sband = local->hw.wiphy->bands[band];
1239 	sta->sta.deflink.supp_rates[band] = supp_rates |
1240 			ieee80211_mandatory_rates(sband, scan_width);
1241 
1242 	spin_lock(&ifibss->incomplete_lock);
1243 	list_add(&sta->list, &ifibss->incomplete_stations);
1244 	spin_unlock(&ifibss->incomplete_lock);
1245 	ieee80211_queue_work(&local->hw, &sdata->work);
1246 }
1247 
ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data * sdata)1248 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1249 {
1250 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1251 	struct ieee80211_local *local = sdata->local;
1252 	struct sta_info *sta, *tmp;
1253 	unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1254 	unsigned long exp_rsn = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1255 
1256 	mutex_lock(&local->sta_mtx);
1257 
1258 	list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1259 		unsigned long last_active = ieee80211_sta_last_active(sta);
1260 
1261 		if (sdata != sta->sdata)
1262 			continue;
1263 
1264 		if (time_is_before_jiffies(last_active + exp_time) ||
1265 		    (time_is_before_jiffies(last_active + exp_rsn) &&
1266 		     sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1267 			u8 frame_buf[IEEE80211_DEAUTH_FRAME_LEN];
1268 
1269 			sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1270 				sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1271 				"not authorized " : "", sta->sta.addr);
1272 
1273 			ieee80211_send_deauth_disassoc(sdata, sta->sta.addr,
1274 						       ifibss->bssid,
1275 						       IEEE80211_STYPE_DEAUTH,
1276 						       WLAN_REASON_DEAUTH_LEAVING,
1277 						       true, frame_buf);
1278 			WARN_ON(__sta_info_destroy(sta));
1279 		}
1280 	}
1281 
1282 	mutex_unlock(&local->sta_mtx);
1283 }
1284 
1285 /*
1286  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1287  */
1288 
ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data * sdata)1289 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1290 {
1291 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1292 	enum nl80211_bss_scan_width scan_width;
1293 
1294 	sdata_assert_lock(sdata);
1295 
1296 	mod_timer(&ifibss->timer,
1297 		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1298 
1299 	ieee80211_ibss_sta_expire(sdata);
1300 
1301 	if (time_before(jiffies, ifibss->last_scan_completed +
1302 		       IEEE80211_IBSS_MERGE_INTERVAL))
1303 		return;
1304 
1305 	if (ieee80211_sta_active_ibss(sdata))
1306 		return;
1307 
1308 	if (ifibss->fixed_channel)
1309 		return;
1310 
1311 	sdata_info(sdata,
1312 		   "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1313 
1314 	scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1315 	ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1316 				    NULL, 0, scan_width);
1317 }
1318 
ieee80211_sta_create_ibss(struct ieee80211_sub_if_data * sdata)1319 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1320 {
1321 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1322 	u8 bssid[ETH_ALEN];
1323 	u16 capability;
1324 	int i;
1325 
1326 	sdata_assert_lock(sdata);
1327 
1328 	if (ifibss->fixed_bssid) {
1329 		memcpy(bssid, ifibss->bssid, ETH_ALEN);
1330 	} else {
1331 		/* Generate random, not broadcast, locally administered BSSID. Mix in
1332 		 * own MAC address to make sure that devices that do not have proper
1333 		 * random number generator get different BSSID. */
1334 		get_random_bytes(bssid, ETH_ALEN);
1335 		for (i = 0; i < ETH_ALEN; i++)
1336 			bssid[i] ^= sdata->vif.addr[i];
1337 		bssid[0] &= ~0x01;
1338 		bssid[0] |= 0x02;
1339 	}
1340 
1341 	sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1342 
1343 	capability = WLAN_CAPABILITY_IBSS;
1344 
1345 	if (ifibss->privacy)
1346 		capability |= WLAN_CAPABILITY_PRIVACY;
1347 
1348 	__ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1349 				  &ifibss->chandef, ifibss->basic_rates,
1350 				  capability, 0, true);
1351 }
1352 
ibss_setup_channels(struct wiphy * wiphy,struct ieee80211_channel ** channels,unsigned int channels_max,u32 center_freq,u32 width)1353 static unsigned int ibss_setup_channels(struct wiphy *wiphy,
1354 					struct ieee80211_channel **channels,
1355 					unsigned int channels_max,
1356 					u32 center_freq, u32 width)
1357 {
1358 	struct ieee80211_channel *chan = NULL;
1359 	unsigned int n_chan = 0;
1360 	u32 start_freq, end_freq, freq;
1361 
1362 	if (width <= 20) {
1363 		start_freq = center_freq;
1364 		end_freq = center_freq;
1365 	} else {
1366 		start_freq = center_freq - width / 2 + 10;
1367 		end_freq = center_freq + width / 2 - 10;
1368 	}
1369 
1370 	for (freq = start_freq; freq <= end_freq; freq += 20) {
1371 		chan = ieee80211_get_channel(wiphy, freq);
1372 		if (!chan)
1373 			continue;
1374 		if (n_chan >= channels_max)
1375 			return n_chan;
1376 
1377 		channels[n_chan] = chan;
1378 		n_chan++;
1379 	}
1380 
1381 	return n_chan;
1382 }
1383 
1384 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)1385 ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
1386 				   const struct cfg80211_chan_def *chandef,
1387 				   struct ieee80211_channel **channels,
1388 				   unsigned int channels_max)
1389 {
1390 	unsigned int n_chan = 0;
1391 	u32 width, cf1, cf2 = 0;
1392 
1393 	switch (chandef->width) {
1394 	case NL80211_CHAN_WIDTH_40:
1395 		width = 40;
1396 		break;
1397 	case NL80211_CHAN_WIDTH_80P80:
1398 		cf2 = chandef->center_freq2;
1399 		fallthrough;
1400 	case NL80211_CHAN_WIDTH_80:
1401 		width = 80;
1402 		break;
1403 	case NL80211_CHAN_WIDTH_160:
1404 		width = 160;
1405 		break;
1406 	default:
1407 		width = 20;
1408 		break;
1409 	}
1410 
1411 	cf1 = chandef->center_freq1;
1412 
1413 	n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
1414 
1415 	if (cf2)
1416 		n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
1417 					      channels_max - n_chan, cf2,
1418 					      width);
1419 
1420 	return n_chan;
1421 }
1422 
1423 /*
1424  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1425  */
1426 
ieee80211_sta_find_ibss(struct ieee80211_sub_if_data * sdata)1427 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1428 {
1429 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1430 	struct ieee80211_local *local = sdata->local;
1431 	struct cfg80211_bss *cbss;
1432 	struct ieee80211_channel *chan = NULL;
1433 	const u8 *bssid = NULL;
1434 	enum nl80211_bss_scan_width scan_width;
1435 	int active_ibss;
1436 
1437 	sdata_assert_lock(sdata);
1438 
1439 	active_ibss = ieee80211_sta_active_ibss(sdata);
1440 	ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1441 
1442 	if (active_ibss)
1443 		return;
1444 
1445 	if (ifibss->fixed_bssid)
1446 		bssid = ifibss->bssid;
1447 	if (ifibss->fixed_channel)
1448 		chan = ifibss->chandef.chan;
1449 	if (!is_zero_ether_addr(ifibss->bssid))
1450 		bssid = ifibss->bssid;
1451 	cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1452 				ifibss->ssid, ifibss->ssid_len,
1453 				IEEE80211_BSS_TYPE_IBSS,
1454 				IEEE80211_PRIVACY(ifibss->privacy));
1455 
1456 	if (cbss) {
1457 		struct ieee80211_bss *bss;
1458 
1459 		bss = (void *)cbss->priv;
1460 		ibss_dbg(sdata,
1461 			 "sta_find_ibss: selected %pM current %pM\n",
1462 			 cbss->bssid, ifibss->bssid);
1463 		sdata_info(sdata,
1464 			   "Selected IBSS BSSID %pM based on configured SSID\n",
1465 			   cbss->bssid);
1466 
1467 		ieee80211_sta_join_ibss(sdata, bss);
1468 		ieee80211_rx_bss_put(local, bss);
1469 		return;
1470 	}
1471 
1472 	/* if a fixed bssid and a fixed freq have been provided create the IBSS
1473 	 * directly and do not waste time scanning
1474 	 */
1475 	if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1476 		sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1477 			   bssid);
1478 		ieee80211_sta_create_ibss(sdata);
1479 		return;
1480 	}
1481 
1482 
1483 	ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1484 
1485 	/* Selected IBSS not found in current scan results - try to scan */
1486 	if (time_after(jiffies, ifibss->last_scan_completed +
1487 					IEEE80211_SCAN_INTERVAL)) {
1488 		struct ieee80211_channel *channels[8];
1489 		unsigned int num;
1490 
1491 		sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1492 
1493 		scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1494 
1495 		if (ifibss->fixed_channel) {
1496 			num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
1497 								 &ifibss->chandef,
1498 								 channels,
1499 								 ARRAY_SIZE(channels));
1500 			ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1501 						    ifibss->ssid_len, channels,
1502 						    num, scan_width);
1503 		} else {
1504 			ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1505 						    ifibss->ssid_len, NULL,
1506 						    0, scan_width);
1507 		}
1508 	} else {
1509 		int interval = IEEE80211_SCAN_INTERVAL;
1510 
1511 		if (time_after(jiffies, ifibss->ibss_join_req +
1512 			       IEEE80211_IBSS_JOIN_TIMEOUT))
1513 			ieee80211_sta_create_ibss(sdata);
1514 
1515 		mod_timer(&ifibss->timer,
1516 			  round_jiffies(jiffies + interval));
1517 	}
1518 }
1519 
ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data * sdata,struct sk_buff * req)1520 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1521 					struct sk_buff *req)
1522 {
1523 	struct ieee80211_mgmt *mgmt = (void *)req->data;
1524 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1525 	struct ieee80211_local *local = sdata->local;
1526 	int tx_last_beacon, len = req->len;
1527 	struct sk_buff *skb;
1528 	struct beacon_data *presp;
1529 	u8 *pos, *end;
1530 
1531 	sdata_assert_lock(sdata);
1532 
1533 	presp = sdata_dereference(ifibss->presp, sdata);
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, "RX ProbeReq SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
1542 	ibss_dbg(sdata, "\tBSSID=%pM (tx_last_beacon=%d)\n",
1543 		 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 	skb_put_data(skb, 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 	elems = ieee802_11_parse_elems(mgmt->u.probe_resp.variable,
1606 				       len - baselen, false, NULL);
1607 
1608 	if (elems) {
1609 		ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, elems);
1610 		kfree(elems);
1611 	}
1612 }
1613 
ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb)1614 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1615 				   struct sk_buff *skb)
1616 {
1617 	struct ieee80211_rx_status *rx_status;
1618 	struct ieee80211_mgmt *mgmt;
1619 	u16 fc;
1620 	struct ieee802_11_elems *elems;
1621 	int ies_len;
1622 
1623 	rx_status = IEEE80211_SKB_RXCB(skb);
1624 	mgmt = (struct ieee80211_mgmt *) skb->data;
1625 	fc = le16_to_cpu(mgmt->frame_control);
1626 
1627 	sdata_lock(sdata);
1628 
1629 	if (!sdata->u.ibss.ssid_len)
1630 		goto mgmt_out; /* not ready to merge yet */
1631 
1632 	switch (fc & IEEE80211_FCTL_STYPE) {
1633 	case IEEE80211_STYPE_PROBE_REQ:
1634 		ieee80211_rx_mgmt_probe_req(sdata, skb);
1635 		break;
1636 	case IEEE80211_STYPE_PROBE_RESP:
1637 	case IEEE80211_STYPE_BEACON:
1638 		ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1639 					       rx_status);
1640 		break;
1641 	case IEEE80211_STYPE_AUTH:
1642 		ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1643 		break;
1644 	case IEEE80211_STYPE_DEAUTH:
1645 		ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1646 		break;
1647 	case IEEE80211_STYPE_ACTION:
1648 		switch (mgmt->u.action.category) {
1649 		case WLAN_CATEGORY_SPECTRUM_MGMT:
1650 			ies_len = skb->len -
1651 				  offsetof(struct ieee80211_mgmt,
1652 					   u.action.u.chan_switch.variable);
1653 
1654 			if (ies_len < 0)
1655 				break;
1656 
1657 			elems = ieee802_11_parse_elems(
1658 				mgmt->u.action.u.chan_switch.variable,
1659 				ies_len, true, NULL);
1660 
1661 			if (elems && !elems->parse_error)
1662 				ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt,
1663 								skb->len,
1664 								rx_status,
1665 								elems);
1666 			kfree(elems);
1667 			break;
1668 		}
1669 	}
1670 
1671  mgmt_out:
1672 	sdata_unlock(sdata);
1673 }
1674 
ieee80211_ibss_work(struct ieee80211_sub_if_data * sdata)1675 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1676 {
1677 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1678 	struct sta_info *sta;
1679 
1680 	sdata_lock(sdata);
1681 
1682 	/*
1683 	 * Work could be scheduled after scan or similar
1684 	 * when we aren't even joined (or trying) with a
1685 	 * network.
1686 	 */
1687 	if (!ifibss->ssid_len)
1688 		goto out;
1689 
1690 	spin_lock_bh(&ifibss->incomplete_lock);
1691 	while (!list_empty(&ifibss->incomplete_stations)) {
1692 		sta = list_first_entry(&ifibss->incomplete_stations,
1693 				       struct sta_info, list);
1694 		list_del(&sta->list);
1695 		spin_unlock_bh(&ifibss->incomplete_lock);
1696 
1697 		ieee80211_ibss_finish_sta(sta);
1698 		rcu_read_unlock();
1699 		spin_lock_bh(&ifibss->incomplete_lock);
1700 	}
1701 	spin_unlock_bh(&ifibss->incomplete_lock);
1702 
1703 	switch (ifibss->state) {
1704 	case IEEE80211_IBSS_MLME_SEARCH:
1705 		ieee80211_sta_find_ibss(sdata);
1706 		break;
1707 	case IEEE80211_IBSS_MLME_JOINED:
1708 		ieee80211_sta_merge_ibss(sdata);
1709 		break;
1710 	default:
1711 		WARN_ON(1);
1712 		break;
1713 	}
1714 
1715  out:
1716 	sdata_unlock(sdata);
1717 }
1718 
ieee80211_ibss_timer(struct timer_list * t)1719 static void ieee80211_ibss_timer(struct timer_list *t)
1720 {
1721 	struct ieee80211_sub_if_data *sdata =
1722 		from_timer(sdata, t, u.ibss.timer);
1723 
1724 	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1725 }
1726 
ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data * sdata)1727 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1728 {
1729 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1730 
1731 	timer_setup(&ifibss->timer, ieee80211_ibss_timer, 0);
1732 	INIT_LIST_HEAD(&ifibss->incomplete_stations);
1733 	spin_lock_init(&ifibss->incomplete_lock);
1734 	INIT_WORK(&ifibss->csa_connection_drop_work,
1735 		  ieee80211_csa_connection_drop_work);
1736 }
1737 
1738 /* scan finished notification */
ieee80211_ibss_notify_scan_completed(struct ieee80211_local * local)1739 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1740 {
1741 	struct ieee80211_sub_if_data *sdata;
1742 
1743 	mutex_lock(&local->iflist_mtx);
1744 	list_for_each_entry(sdata, &local->interfaces, list) {
1745 		if (!ieee80211_sdata_running(sdata))
1746 			continue;
1747 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1748 			continue;
1749 		sdata->u.ibss.last_scan_completed = jiffies;
1750 	}
1751 	mutex_unlock(&local->iflist_mtx);
1752 }
1753 
ieee80211_ibss_join(struct ieee80211_sub_if_data * sdata,struct cfg80211_ibss_params * params)1754 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1755 			struct cfg80211_ibss_params *params)
1756 {
1757 	u32 changed = 0;
1758 	u32 rate_flags;
1759 	struct ieee80211_supported_band *sband;
1760 	enum ieee80211_chanctx_mode chanmode;
1761 	struct ieee80211_local *local = sdata->local;
1762 	int radar_detect_width = 0;
1763 	int i;
1764 	int ret;
1765 
1766 	if (params->chandef.chan->freq_offset) {
1767 		/* this may work, but is untested */
1768 		return -EOPNOTSUPP;
1769 	}
1770 
1771 	ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1772 					    &params->chandef,
1773 					    sdata->wdev.iftype);
1774 	if (ret < 0)
1775 		return ret;
1776 
1777 	if (ret > 0) {
1778 		if (!params->userspace_handles_dfs)
1779 			return -EINVAL;
1780 		radar_detect_width = BIT(params->chandef.width);
1781 	}
1782 
1783 	chanmode = (params->channel_fixed && !ret) ?
1784 		IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1785 
1786 	mutex_lock(&local->chanctx_mtx);
1787 	ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1788 					   radar_detect_width);
1789 	mutex_unlock(&local->chanctx_mtx);
1790 	if (ret < 0)
1791 		return ret;
1792 
1793 	if (params->bssid) {
1794 		memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1795 		sdata->u.ibss.fixed_bssid = true;
1796 	} else
1797 		sdata->u.ibss.fixed_bssid = false;
1798 
1799 	sdata->u.ibss.privacy = params->privacy;
1800 	sdata->u.ibss.control_port = params->control_port;
1801 	sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1802 	sdata->u.ibss.basic_rates = params->basic_rates;
1803 	sdata->u.ibss.last_scan_completed = jiffies;
1804 
1805 	/* fix basic_rates if channel does not support these rates */
1806 	rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1807 	sband = local->hw.wiphy->bands[params->chandef.chan->band];
1808 	for (i = 0; i < sband->n_bitrates; i++) {
1809 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1810 			sdata->u.ibss.basic_rates &= ~BIT(i);
1811 	}
1812 	memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1813 	       sizeof(params->mcast_rate));
1814 
1815 	sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1816 
1817 	sdata->u.ibss.chandef = params->chandef;
1818 	sdata->u.ibss.fixed_channel = params->channel_fixed;
1819 
1820 	if (params->ie) {
1821 		sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1822 					   GFP_KERNEL);
1823 		if (sdata->u.ibss.ie)
1824 			sdata->u.ibss.ie_len = params->ie_len;
1825 	}
1826 
1827 	sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1828 	sdata->u.ibss.ibss_join_req = jiffies;
1829 
1830 	memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1831 	sdata->u.ibss.ssid_len = params->ssid_len;
1832 
1833 	memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1834 	       sizeof(sdata->u.ibss.ht_capa));
1835 	memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1836 	       sizeof(sdata->u.ibss.ht_capa_mask));
1837 
1838 	/*
1839 	 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1840 	 * reserved, but an HT STA shall protect HT transmissions as though
1841 	 * the HT Protection field were set to non-HT mixed mode.
1842 	 *
1843 	 * In an IBSS, the RIFS Mode field of the HT Operation element is
1844 	 * also reserved, but an HT STA shall operate as though this field
1845 	 * were set to 1.
1846 	 */
1847 
1848 	sdata->vif.bss_conf.ht_operation_mode |=
1849 		  IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1850 		| IEEE80211_HT_PARAM_RIFS_MODE;
1851 
1852 	changed |= BSS_CHANGED_HT | BSS_CHANGED_MCAST_RATE;
1853 	ieee80211_link_info_change_notify(sdata, &sdata->deflink, changed);
1854 
1855 	sdata->deflink.smps_mode = IEEE80211_SMPS_OFF;
1856 	sdata->deflink.needed_rx_chains = local->rx_chains;
1857 	sdata->control_port_over_nl80211 = params->control_port_over_nl80211;
1858 
1859 	ieee80211_queue_work(&local->hw, &sdata->work);
1860 
1861 	return 0;
1862 }
1863 
ieee80211_ibss_leave(struct ieee80211_sub_if_data * sdata)1864 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1865 {
1866 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1867 
1868 	ieee80211_ibss_disconnect(sdata);
1869 	ifibss->ssid_len = 0;
1870 	eth_zero_addr(ifibss->bssid);
1871 
1872 	/* remove beacon */
1873 	kfree(sdata->u.ibss.ie);
1874 	sdata->u.ibss.ie = NULL;
1875 	sdata->u.ibss.ie_len = 0;
1876 
1877 	/* on the next join, re-program HT parameters */
1878 	memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1879 	memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1880 
1881 	synchronize_rcu();
1882 
1883 	skb_queue_purge(&sdata->skb_queue);
1884 
1885 	del_timer_sync(&sdata->u.ibss.timer);
1886 
1887 	return 0;
1888 }
1889