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v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Scanning implementation
   4 *
   5 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
   6 * Copyright 2004, Instant802 Networks, Inc.
   7 * Copyright 2005, Devicescape Software, Inc.
   8 * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
   9 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
  10 * Copyright 2013-2015  Intel Mobile Communications GmbH
  11 * Copyright 2016-2017  Intel Deutschland GmbH
  12 * Copyright (C) 2018-2024 Intel Corporation
 
 
 
  13 */
  14
  15#include <linux/if_arp.h>
  16#include <linux/etherdevice.h>
  17#include <linux/rtnetlink.h>
  18#include <net/sch_generic.h>
  19#include <linux/slab.h>
  20#include <linux/export.h>
  21#include <linux/random.h>
  22#include <net/mac80211.h>
  23
  24#include "ieee80211_i.h"
  25#include "driver-ops.h"
  26#include "mesh.h"
  27
  28#define IEEE80211_PROBE_DELAY (HZ / 33)
  29#define IEEE80211_CHANNEL_TIME (HZ / 33)
  30#define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 9)
  31
  32void ieee80211_rx_bss_put(struct ieee80211_local *local,
  33			  struct ieee80211_bss *bss)
  34{
  35	if (!bss)
  36		return;
  37	cfg80211_put_bss(local->hw.wiphy,
  38			 container_of((void *)bss, struct cfg80211_bss, priv));
  39}
  40
  41static bool is_uapsd_supported(struct ieee802_11_elems *elems)
  42{
  43	u8 qos_info;
  44
  45	if (elems->wmm_info && elems->wmm_info_len == 7
  46	    && elems->wmm_info[5] == 1)
  47		qos_info = elems->wmm_info[6];
  48	else if (elems->wmm_param && elems->wmm_param_len == 24
  49		 && elems->wmm_param[5] == 1)
  50		qos_info = elems->wmm_param[6];
  51	else
  52		/* no valid wmm information or parameter element found */
  53		return false;
  54
  55	return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD;
  56}
  57
  58struct inform_bss_update_data {
  59	struct ieee80211_rx_status *rx_status;
  60	bool beacon;
  61};
  62
  63void ieee80211_inform_bss(struct wiphy *wiphy,
  64			  struct cfg80211_bss *cbss,
  65			  const struct cfg80211_bss_ies *ies,
  66			  void *data)
  67{
  68	struct ieee80211_local *local = wiphy_priv(wiphy);
  69	struct inform_bss_update_data *update_data = data;
  70	struct ieee80211_bss *bss = (void *)cbss->priv;
  71	struct ieee80211_rx_status *rx_status;
  72	struct ieee802_11_elems *elems;
  73	int clen, srlen;
 
 
 
 
 
  74
  75	/* This happens while joining an IBSS */
  76	if (!update_data)
  77		return;
 
 
 
  78
  79	elems = ieee802_11_parse_elems(ies->data, ies->len, false, NULL);
  80	if (!elems)
  81		return;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  82
  83	rx_status = update_data->rx_status;
  84
  85	if (update_data->beacon)
  86		bss->device_ts_beacon = rx_status->device_timestamp;
  87	else
  88		bss->device_ts_presp = rx_status->device_timestamp;
  89
  90	if (elems->parse_error) {
  91		if (update_data->beacon)
  92			bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON;
  93		else
  94			bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP;
  95	} else {
  96		if (update_data->beacon)
  97			bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON;
  98		else
  99			bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP;
 100	}
 101
 102	/* save the ERP value so that it is available at association time */
 103	if (elems->erp_info && (!elems->parse_error ||
 104				!(bss->valid_data & IEEE80211_BSS_VALID_ERP))) {
 105		bss->erp_value = elems->erp_info[0];
 106		bss->has_erp_value = true;
 107		if (!elems->parse_error)
 108			bss->valid_data |= IEEE80211_BSS_VALID_ERP;
 109	}
 110
 111	/* replace old supported rates if we get new values */
 112	if (!elems->parse_error ||
 113	    !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) {
 114		srlen = 0;
 115		if (elems->supp_rates) {
 116			clen = IEEE80211_MAX_SUPP_RATES;
 117			if (clen > elems->supp_rates_len)
 118				clen = elems->supp_rates_len;
 119			memcpy(bss->supp_rates, elems->supp_rates, clen);
 120			srlen += clen;
 121		}
 122		if (elems->ext_supp_rates) {
 123			clen = IEEE80211_MAX_SUPP_RATES - srlen;
 124			if (clen > elems->ext_supp_rates_len)
 125				clen = elems->ext_supp_rates_len;
 126			memcpy(bss->supp_rates + srlen, elems->ext_supp_rates,
 127			       clen);
 128			srlen += clen;
 129		}
 130		if (srlen) {
 131			bss->supp_rates_len = srlen;
 132			if (!elems->parse_error)
 133				bss->valid_data |= IEEE80211_BSS_VALID_RATES;
 134		}
 135	}
 136
 137	if (!elems->parse_error ||
 138	    !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) {
 139		bss->wmm_used = elems->wmm_param || elems->wmm_info;
 140		bss->uapsd_supported = is_uapsd_supported(elems);
 141		if (!elems->parse_error)
 142			bss->valid_data |= IEEE80211_BSS_VALID_WMM;
 143	}
 144
 145	if (update_data->beacon) {
 146		struct ieee80211_supported_band *sband =
 147			local->hw.wiphy->bands[rx_status->band];
 148		if (!(rx_status->encoding == RX_ENC_HT) &&
 149		    !(rx_status->encoding == RX_ENC_VHT))
 150			bss->beacon_rate =
 151				&sband->bitrates[rx_status->rate_idx];
 152	}
 153
 154	if (elems->vht_cap_elem)
 155		bss->vht_cap_info =
 156			le32_to_cpu(elems->vht_cap_elem->vht_cap_info);
 157	else
 158		bss->vht_cap_info = 0;
 159
 160	kfree(elems);
 161}
 162
 163struct ieee80211_bss *
 164ieee80211_bss_info_update(struct ieee80211_local *local,
 165			  struct ieee80211_rx_status *rx_status,
 166			  struct ieee80211_mgmt *mgmt, size_t len,
 167			  struct ieee80211_channel *channel)
 168{
 169	bool beacon = ieee80211_is_beacon(mgmt->frame_control) ||
 170		      ieee80211_is_s1g_beacon(mgmt->frame_control);
 171	struct cfg80211_bss *cbss;
 172	struct inform_bss_update_data update_data = {
 173		.rx_status = rx_status,
 174		.beacon = beacon,
 175	};
 176	struct cfg80211_inform_bss bss_meta = {
 177		.boottime_ns = rx_status->boottime_ns,
 178		.drv_data = (void *)&update_data,
 179	};
 180	bool signal_valid;
 181	struct ieee80211_sub_if_data *scan_sdata;
 182
 183	if (rx_status->flag & RX_FLAG_NO_SIGNAL_VAL)
 184		bss_meta.signal = 0; /* invalid signal indication */
 185	else if (ieee80211_hw_check(&local->hw, SIGNAL_DBM))
 186		bss_meta.signal = rx_status->signal * 100;
 187	else if (ieee80211_hw_check(&local->hw, SIGNAL_UNSPEC))
 188		bss_meta.signal = (rx_status->signal * 100) / local->hw.max_signal;
 189
 190	bss_meta.chan = channel;
 191
 192	rcu_read_lock();
 193	scan_sdata = rcu_dereference(local->scan_sdata);
 194	if (scan_sdata && scan_sdata->vif.type == NL80211_IFTYPE_STATION &&
 195	    scan_sdata->vif.cfg.assoc &&
 196	    ieee80211_have_rx_timestamp(rx_status)) {
 197		struct ieee80211_bss_conf *link_conf = NULL;
 198
 199		/* for an MLO connection, set the TSF data only in case we have
 200		 * an indication on which of the links the frame was received
 201		 */
 202		if (ieee80211_vif_is_mld(&scan_sdata->vif)) {
 203			if (rx_status->link_valid) {
 204				s8 link_id = rx_status->link_id;
 205
 206				link_conf =
 207					rcu_dereference(scan_sdata->vif.link_conf[link_id]);
 208			}
 209		} else {
 210			link_conf = &scan_sdata->vif.bss_conf;
 211		}
 212
 213		if (link_conf) {
 214			bss_meta.parent_tsf =
 215				ieee80211_calculate_rx_timestamp(local,
 216								 rx_status,
 217								 len + FCS_LEN,
 218								 24);
 219
 220			ether_addr_copy(bss_meta.parent_bssid,
 221					link_conf->bssid);
 222		}
 223	}
 224	rcu_read_unlock();
 225
 226	cbss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta,
 227					      mgmt, len, GFP_ATOMIC);
 228	if (!cbss)
 229		return NULL;
 230
 231	/* In case the signal is invalid update the status */
 232	signal_valid = channel == cbss->channel;
 233	if (!signal_valid)
 234		rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL;
 235
 236	return (void *)cbss->priv;
 237}
 238
 239static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata,
 240					struct ieee80211_channel *channel,
 241					u32 scan_flags, const u8 *da)
 242{
 243	if (!sdata)
 244		return false;
 245
 246	/* accept broadcast on 6 GHz and for OCE */
 247	if (is_broadcast_ether_addr(da) &&
 248	    (channel->band == NL80211_BAND_6GHZ ||
 249	     scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP))
 250		return true;
 251
 252	if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
 253		return true;
 254	return ether_addr_equal(da, sdata->vif.addr);
 255}
 256
 257void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb)
 258{
 259	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
 
 260	struct ieee80211_mgmt *mgmt = (void *)skb->data;
 261	struct ieee80211_bss *bss;
 
 262	struct ieee80211_channel *channel;
 263	size_t min_hdr_len = offsetof(struct ieee80211_mgmt,
 264				      u.probe_resp.variable);
 265
 266	if (!ieee80211_is_probe_resp(mgmt->frame_control) &&
 267	    !ieee80211_is_beacon(mgmt->frame_control) &&
 268	    !ieee80211_is_s1g_beacon(mgmt->frame_control))
 269		return;
 270
 271	if (ieee80211_is_s1g_beacon(mgmt->frame_control)) {
 272		if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
 273			min_hdr_len = offsetof(struct ieee80211_ext,
 274					       u.s1g_short_beacon.variable);
 275		else
 276			min_hdr_len = offsetof(struct ieee80211_ext,
 277					       u.s1g_beacon);
 278	}
 279
 280	if (skb->len < min_hdr_len)
 281		return;
 282
 283	if (test_and_clear_bit(SCAN_BEACON_WAIT, &local->scanning)) {
 284		/*
 285		 * we were passive scanning because of radar/no-IR, but
 286		 * the beacon/proberesp rx gives us an opportunity to upgrade
 287		 * to active scan
 288		 */
 289		set_bit(SCAN_BEACON_DONE, &local->scanning);
 290		wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 0);
 291	}
 292
 293	channel = ieee80211_get_channel_khz(local->hw.wiphy,
 294					    ieee80211_rx_status_to_khz(rx_status));
 295
 296	if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 297		return;
 298
 299	if (ieee80211_is_probe_resp(mgmt->frame_control)) {
 300		struct ieee80211_sub_if_data *sdata1, *sdata2;
 301		struct cfg80211_scan_request *scan_req;
 302		struct cfg80211_sched_scan_request *sched_scan_req;
 303		u32 scan_req_flags = 0, sched_scan_req_flags = 0;
 304
 305		sdata1 = rcu_dereference(local->scan_sdata);
 306		sdata2 = rcu_dereference(local->sched_scan_sdata);
 307
 308		if (likely(!sdata1 && !sdata2))
 309			return;
 310
 311		scan_req = rcu_dereference(local->scan_req);
 312		sched_scan_req = rcu_dereference(local->sched_scan_req);
 313
 314		if (scan_req)
 315			scan_req_flags = scan_req->flags;
 316
 317		if (sched_scan_req)
 318			sched_scan_req_flags = sched_scan_req->flags;
 319
 320		/* ignore ProbeResp to foreign address or non-bcast (OCE)
 321		 * unless scanning with randomised address
 322		 */
 323		if (!ieee80211_scan_accept_presp(sdata1, channel,
 324						 scan_req_flags,
 325						 mgmt->da) &&
 326		    !ieee80211_scan_accept_presp(sdata2, channel,
 327						 sched_scan_req_flags,
 328						 mgmt->da))
 329			return;
 
 
 
 330	} else {
 331		/* Beacons are expected only with broadcast address */
 332		if (!is_broadcast_ether_addr(mgmt->da))
 333			return;
 334	}
 335
 336	/* Do not update the BSS table in case of only monitor interfaces */
 337	if (local->open_count == local->monitors)
 
 
 
 
 
 
 338		return;
 339
 340	bss = ieee80211_bss_info_update(local, rx_status,
 341					mgmt, skb->len,
 342					channel);
 343	if (bss)
 344		ieee80211_rx_bss_put(local, bss);
 345}
 346
 347static void ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef)
 
 
 348{
 349	memset(chandef, 0, sizeof(*chandef));
 350
 351	chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
 
 
 
 
 
 
 
 
 
 352}
 353
 354/* return false if no more work */
 355static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data *sdata)
 356{
 357	struct ieee80211_local *local = sdata->local;
 358	struct cfg80211_scan_request *req;
 359	struct cfg80211_chan_def chandef;
 360	u8 bands_used = 0;
 361	int i, ielen;
 362	u32 *n_chans;
 363	u32 flags = 0;
 364
 365	req = rcu_dereference_protected(local->scan_req,
 366					lockdep_is_held(&local->hw.wiphy->mtx));
 367
 368	if (test_bit(SCAN_HW_CANCELLED, &local->scanning))
 369		return false;
 370
 371	if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
 372		local->hw_scan_req->req.n_channels = req->n_channels;
 373
 374		for (i = 0; i < req->n_channels; i++) {
 375			local->hw_scan_req->req.channels[i] = req->channels[i];
 376			bands_used |= BIT(req->channels[i]->band);
 377		}
 
 
 378	} else {
 379		do {
 380			if (local->hw_scan_band == NUM_NL80211_BANDS)
 381				return false;
 382
 383			n_chans = &local->hw_scan_req->req.n_channels;
 384			*n_chans = 0;
 385
 386			for (i = 0; i < req->n_channels; i++) {
 387				if (req->channels[i]->band !=
 388				    local->hw_scan_band)
 389					continue;
 390				local->hw_scan_req->req.channels[(*n_chans)++] =
 391							req->channels[i];
 392
 393				bands_used |= BIT(req->channels[i]->band);
 394			}
 395
 396			local->hw_scan_band++;
 397		} while (!*n_chans);
 398	}
 399
 400	ieee80211_prepare_scan_chandef(&chandef);
 
 401
 402	if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
 403		flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
 404
 405	ielen = ieee80211_build_preq_ies(sdata,
 406					 (u8 *)local->hw_scan_req->req.ie,
 407					 local->hw_scan_ies_bufsize,
 408					 &local->hw_scan_req->ies,
 409					 req->ie, req->ie_len,
 410					 bands_used, req->rates, &chandef,
 411					 flags);
 412	if (ielen < 0)
 413		return false;
 414	local->hw_scan_req->req.ie_len = ielen;
 415	local->hw_scan_req->req.no_cck = req->no_cck;
 416	ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr);
 417	ether_addr_copy(local->hw_scan_req->req.mac_addr_mask,
 418			req->mac_addr_mask);
 419	ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid);
 420
 421	return true;
 422}
 423
 424static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
 425{
 426	struct ieee80211_local *local = hw_to_local(hw);
 427	bool hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning);
 428	bool was_scanning = local->scanning;
 429	struct cfg80211_scan_request *scan_req;
 430	struct ieee80211_sub_if_data *scan_sdata;
 431	struct ieee80211_sub_if_data *sdata;
 432
 433	lockdep_assert_wiphy(local->hw.wiphy);
 434
 435	/*
 436	 * It's ok to abort a not-yet-running scan (that
 437	 * we have one at all will be verified by checking
 438	 * local->scan_req next), but not to complete it
 439	 * successfully.
 440	 */
 441	if (WARN_ON(!local->scanning && !aborted))
 442		aborted = true;
 443
 444	if (WARN_ON(!local->scan_req))
 445		return;
 446
 447	scan_sdata = rcu_dereference_protected(local->scan_sdata,
 448					       lockdep_is_held(&local->hw.wiphy->mtx));
 449
 450	if (hw_scan && !aborted &&
 451	    !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) &&
 452	    ieee80211_prep_hw_scan(scan_sdata)) {
 453		int rc;
 454
 455		rc = drv_hw_scan(local,
 456			rcu_dereference_protected(local->scan_sdata,
 457						  lockdep_is_held(&local->hw.wiphy->mtx)),
 458			local->hw_scan_req);
 459
 460		if (rc == 0)
 461			return;
 462
 463		/* HW scan failed and is going to be reported as aborted,
 464		 * so clear old scan info.
 465		 */
 466		memset(&local->scan_info, 0, sizeof(local->scan_info));
 467		aborted = true;
 468	}
 469
 470	kfree(local->hw_scan_req);
 471	local->hw_scan_req = NULL;
 472
 473	scan_req = rcu_dereference_protected(local->scan_req,
 474					     lockdep_is_held(&local->hw.wiphy->mtx));
 475
 
 
 
 
 476	RCU_INIT_POINTER(local->scan_req, NULL);
 
 
 
 477	RCU_INIT_POINTER(local->scan_sdata, NULL);
 478
 479	local->scanning = 0;
 480	local->scan_chandef.chan = NULL;
 481
 482	synchronize_rcu();
 483
 484	if (scan_req != local->int_scan_req) {
 485		local->scan_info.aborted = aborted;
 486		cfg80211_scan_done(scan_req, &local->scan_info);
 487	}
 488
 489	/* Set power back to normal operating levels. */
 490	ieee80211_hw_conf_chan(local);
 491
 492	if (!hw_scan && was_scanning) {
 493		ieee80211_configure_filter(local);
 494		drv_sw_scan_complete(local, scan_sdata);
 495		ieee80211_offchannel_return(local);
 496	}
 497
 498	ieee80211_recalc_idle(local);
 499
 500	ieee80211_mlme_notify_scan_completed(local);
 501	ieee80211_ibss_notify_scan_completed(local);
 502
 503	/* Requeue all the work that might have been ignored while
 504	 * the scan was in progress; if there was none this will
 505	 * just be a no-op for the particular interface.
 506	 */
 507	list_for_each_entry(sdata, &local->interfaces, list) {
 508		if (ieee80211_sdata_running(sdata))
 509			wiphy_work_queue(sdata->local->hw.wiphy, &sdata->work);
 510	}
 511
 512	if (was_scanning)
 513		ieee80211_start_next_roc(local);
 514}
 515
 516void ieee80211_scan_completed(struct ieee80211_hw *hw,
 517			      struct cfg80211_scan_info *info)
 518{
 519	struct ieee80211_local *local = hw_to_local(hw);
 520
 521	trace_api_scan_completed(local, info->aborted);
 522
 523	set_bit(SCAN_COMPLETED, &local->scanning);
 524	if (info->aborted)
 525		set_bit(SCAN_ABORTED, &local->scanning);
 526
 527	memcpy(&local->scan_info, info, sizeof(*info));
 528
 529	wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 0);
 530}
 531EXPORT_SYMBOL(ieee80211_scan_completed);
 532
 533static int ieee80211_start_sw_scan(struct ieee80211_local *local,
 534				   struct ieee80211_sub_if_data *sdata)
 535{
 536	/* Software scan is not supported in multi-channel cases */
 537	if (!local->emulate_chanctx)
 538		return -EOPNOTSUPP;
 539
 540	/*
 541	 * Hardware/driver doesn't support hw_scan, so use software
 542	 * scanning instead. First send a nullfunc frame with power save
 543	 * bit on so that AP will buffer the frames for us while we are not
 544	 * listening, then send probe requests to each channel and wait for
 545	 * the responses. After all channels are scanned, tune back to the
 546	 * original channel and send a nullfunc frame with power save bit
 547	 * off to trigger the AP to send us all the buffered frames.
 548	 *
 549	 * Note that while local->sw_scanning is true everything else but
 550	 * nullfunc frames and probe requests will be dropped in
 551	 * ieee80211_tx_h_check_assoc().
 552	 */
 553	drv_sw_scan_start(local, sdata, local->scan_addr);
 554
 555	local->leave_oper_channel_time = jiffies;
 556	local->next_scan_state = SCAN_DECISION;
 557	local->scan_channel_idx = 0;
 558
 559	ieee80211_offchannel_stop_vifs(local);
 560
 561	/* ensure nullfunc is transmitted before leaving operating channel */
 562	ieee80211_flush_queues(local, NULL, false);
 563
 564	ieee80211_configure_filter(local);
 565
 566	/* We need to set power level at maximum rate for scanning. */
 567	ieee80211_hw_conf_chan(local);
 568
 569	wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 0);
 
 570
 571	return 0;
 572}
 573
 574static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata)
 575{
 576	struct ieee80211_local *local = sdata->local;
 577	struct ieee80211_sub_if_data *sdata_iter;
 578	unsigned int link_id;
 579
 580	lockdep_assert_wiphy(local->hw.wiphy);
 581
 582	if (!ieee80211_is_radar_required(local))
 583		return true;
 584
 585	if (!regulatory_pre_cac_allowed(local->hw.wiphy))
 586		return false;
 587
 588	list_for_each_entry(sdata_iter, &local->interfaces, list) {
 589		for_each_valid_link(&sdata_iter->wdev, link_id)
 590			if (sdata_iter->wdev.links[link_id].cac_started)
 591				return false;
 592	}
 593
 594	return true;
 595}
 596
 597static bool ieee80211_can_scan(struct ieee80211_local *local,
 598			       struct ieee80211_sub_if_data *sdata)
 599{
 600	if (!__ieee80211_can_leave_ch(sdata))
 601		return false;
 602
 603	if (!list_empty(&local->roc_list))
 604		return false;
 605
 606	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
 607	    sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL)
 608		return false;
 609
 610	return true;
 611}
 612
 613void ieee80211_run_deferred_scan(struct ieee80211_local *local)
 614{
 615	lockdep_assert_wiphy(local->hw.wiphy);
 616
 617	if (!local->scan_req || local->scanning)
 618		return;
 619
 620	if (!ieee80211_can_scan(local,
 621				rcu_dereference_protected(
 622					local->scan_sdata,
 623					lockdep_is_held(&local->hw.wiphy->mtx))))
 624		return;
 625
 626	wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work,
 627				 round_jiffies_relative(0));
 628}
 629
 630static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata,
 631					  const u8 *src, const u8 *dst,
 632					  const u8 *ssid, size_t ssid_len,
 633					  const u8 *ie, size_t ie_len,
 634					  u32 ratemask, u32 flags, u32 tx_flags,
 635					  struct ieee80211_channel *channel)
 636{
 637	struct sk_buff *skb;
 638
 639	skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel,
 640					ssid, ssid_len,
 641					ie, ie_len, flags);
 642
 643	if (skb) {
 644		if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) {
 645			struct ieee80211_hdr *hdr = (void *)skb->data;
 646			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 647			u16 sn = get_random_u16();
 648
 649			info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO;
 650			hdr->seq_ctrl =
 651				cpu_to_le16(IEEE80211_SN_TO_SEQ(sn));
 652		}
 653		IEEE80211_SKB_CB(skb)->flags |= tx_flags;
 654		IEEE80211_SKB_CB(skb)->control.flags |= IEEE80211_TX_CTRL_DONT_USE_RATE_MASK;
 655		ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band);
 656	}
 657}
 658
 659static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
 660					    unsigned long *next_delay)
 661{
 662	int i;
 663	struct ieee80211_sub_if_data *sdata;
 664	struct cfg80211_scan_request *scan_req;
 665	enum nl80211_band band = local->hw.conf.chandef.chan->band;
 666	u32 flags = 0, tx_flags;
 667
 668	scan_req = rcu_dereference_protected(local->scan_req,
 669					     lockdep_is_held(&local->hw.wiphy->mtx));
 670
 671	tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
 672	if (scan_req->no_cck)
 673		tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
 674	if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
 675		flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
 676	if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN)
 677		flags |= IEEE80211_PROBE_FLAG_RANDOM_SN;
 678
 679	sdata = rcu_dereference_protected(local->scan_sdata,
 680					  lockdep_is_held(&local->hw.wiphy->mtx));
 681
 682	for (i = 0; i < scan_req->n_ssids; i++)
 683		ieee80211_send_scan_probe_req(
 684			sdata, local->scan_addr, scan_req->bssid,
 685			scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len,
 686			scan_req->ie, scan_req->ie_len,
 687			scan_req->rates[band], flags,
 688			tx_flags, local->hw.conf.chandef.chan);
 689
 690	/*
 691	 * After sending probe requests, wait for probe responses
 692	 * on the channel.
 693	 */
 694	*next_delay = msecs_to_jiffies(scan_req->duration) >
 695		      IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME ?
 696		      msecs_to_jiffies(scan_req->duration) - IEEE80211_PROBE_DELAY :
 697		      IEEE80211_CHANNEL_TIME;
 698	local->next_scan_state = SCAN_DECISION;
 699}
 700
 701static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
 702				  struct cfg80211_scan_request *req)
 703{
 704	struct ieee80211_local *local = sdata->local;
 705	bool hw_scan = local->ops->hw_scan;
 706	int rc;
 707
 708	lockdep_assert_wiphy(local->hw.wiphy);
 709
 710	if (local->scan_req)
 711		return -EBUSY;
 712
 713	/* For an MLO connection, if a link ID was specified, validate that it
 714	 * is indeed active.
 715	 */
 716	if (ieee80211_vif_is_mld(&sdata->vif) && req->tsf_report_link_id >= 0 &&
 717	    !(sdata->vif.active_links & BIT(req->tsf_report_link_id)))
 718		return -EINVAL;
 719
 720	if (!__ieee80211_can_leave_ch(sdata))
 721		return -EBUSY;
 722
 723	if (!ieee80211_can_scan(local, sdata)) {
 724		/* wait for the work to finish/time out */
 725		rcu_assign_pointer(local->scan_req, req);
 726		rcu_assign_pointer(local->scan_sdata, sdata);
 727		return 0;
 728	}
 729
 730 again:
 731	if (hw_scan) {
 732		u8 *ies;
 733
 734		local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len;
 735
 736		if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
 737			int i, n_bands = 0;
 738			u8 bands_counted = 0;
 739
 740			for (i = 0; i < req->n_channels; i++) {
 741				if (bands_counted & BIT(req->channels[i]->band))
 742					continue;
 743				bands_counted |= BIT(req->channels[i]->band);
 744				n_bands++;
 745			}
 746
 747			local->hw_scan_ies_bufsize *= n_bands;
 748		}
 749
 750		local->hw_scan_req = kmalloc(struct_size(local->hw_scan_req,
 751							 req.channels,
 752							 req->n_channels) +
 753					     local->hw_scan_ies_bufsize,
 754					     GFP_KERNEL);
 755		if (!local->hw_scan_req)
 756			return -ENOMEM;
 757
 758		local->hw_scan_req->req.ssids = req->ssids;
 759		local->hw_scan_req->req.n_ssids = req->n_ssids;
 760		/* None of the channels are actually set
 761		 * up but let UBSAN know the boundaries.
 762		 */
 763		local->hw_scan_req->req.n_channels = req->n_channels;
 764
 765		ies = (u8 *)local->hw_scan_req +
 766			sizeof(*local->hw_scan_req) +
 767			req->n_channels * sizeof(req->channels[0]);
 768		local->hw_scan_req->req.ie = ies;
 769		local->hw_scan_req->req.flags = req->flags;
 770		eth_broadcast_addr(local->hw_scan_req->req.bssid);
 771		local->hw_scan_req->req.duration = req->duration;
 772		local->hw_scan_req->req.duration_mandatory =
 773			req->duration_mandatory;
 774		local->hw_scan_req->req.tsf_report_link_id =
 775			req->tsf_report_link_id;
 776
 777		local->hw_scan_band = 0;
 778		local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params;
 779		local->hw_scan_req->req.scan_6ghz_params =
 780			req->scan_6ghz_params;
 781		local->hw_scan_req->req.scan_6ghz = req->scan_6ghz;
 782
 783		/*
 784		 * After allocating local->hw_scan_req, we must
 785		 * go through until ieee80211_prep_hw_scan(), so
 786		 * anything that might be changed here and leave
 787		 * this function early must not go after this
 788		 * allocation.
 789		 */
 790	}
 791
 792	rcu_assign_pointer(local->scan_req, req);
 793	rcu_assign_pointer(local->scan_sdata, sdata);
 794
 795	if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
 796		get_random_mask_addr(local->scan_addr,
 797				     req->mac_addr,
 798				     req->mac_addr_mask);
 799	else
 800		memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN);
 801
 802	if (hw_scan) {
 803		__set_bit(SCAN_HW_SCANNING, &local->scanning);
 804	} else if ((req->n_channels == 1) &&
 805		   (req->channels[0] == local->hw.conf.chandef.chan)) {
 806		/*
 807		 * If we are scanning only on the operating channel
 808		 * then we do not need to stop normal activities
 809		 */
 810		unsigned long next_delay;
 811
 812		__set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
 813
 814		ieee80211_recalc_idle(local);
 815
 816		/* Notify driver scan is starting, keep order of operations
 817		 * same as normal software scan, in case that matters. */
 818		drv_sw_scan_start(local, sdata, local->scan_addr);
 819
 820		ieee80211_configure_filter(local); /* accept probe-responses */
 821
 822		/* We need to ensure power level is at max for scanning. */
 823		ieee80211_hw_conf_chan(local);
 824
 825		if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR |
 826						IEEE80211_CHAN_RADAR)) ||
 827		    !req->n_ssids) {
 828			next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
 829			if (req->n_ssids)
 830				set_bit(SCAN_BEACON_WAIT, &local->scanning);
 831		} else {
 832			ieee80211_scan_state_send_probe(local, &next_delay);
 833			next_delay = IEEE80211_CHANNEL_TIME;
 834		}
 835
 836		/* Now, just wait a bit and we are all done! */
 837		wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work,
 838					 next_delay);
 839		return 0;
 840	} else {
 841		/* Do normal software scan */
 842		__set_bit(SCAN_SW_SCANNING, &local->scanning);
 843	}
 844
 845	ieee80211_recalc_idle(local);
 846
 847	if (hw_scan) {
 848		WARN_ON(!ieee80211_prep_hw_scan(sdata));
 849		rc = drv_hw_scan(local, sdata, local->hw_scan_req);
 850	} else {
 851		rc = ieee80211_start_sw_scan(local, sdata);
 852	}
 853
 854	if (rc) {
 855		kfree(local->hw_scan_req);
 856		local->hw_scan_req = NULL;
 857		local->scanning = 0;
 858
 859		ieee80211_recalc_idle(local);
 860
 861		local->scan_req = NULL;
 862		RCU_INIT_POINTER(local->scan_sdata, NULL);
 863	}
 864
 865	if (hw_scan && rc == 1) {
 866		/*
 867		 * we can't fall back to software for P2P-GO
 868		 * as it must update NoA etc.
 869		 */
 870		if (ieee80211_vif_type_p2p(&sdata->vif) ==
 871				NL80211_IFTYPE_P2P_GO)
 872			return -EOPNOTSUPP;
 873		hw_scan = false;
 874		goto again;
 875	}
 876
 877	return rc;
 878}
 879
 880static unsigned long
 881ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
 882{
 883	/*
 884	 * TODO: channel switching also consumes quite some time,
 885	 * add that delay as well to get a better estimation
 886	 */
 887	if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR))
 888		return IEEE80211_PASSIVE_CHANNEL_TIME;
 889	return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
 890}
 891
 892static void ieee80211_scan_state_decision(struct ieee80211_local *local,
 893					  unsigned long *next_delay)
 894{
 895	bool associated = false;
 896	bool tx_empty = true;
 897	bool bad_latency;
 898	struct ieee80211_sub_if_data *sdata;
 899	struct ieee80211_channel *next_chan;
 900	enum mac80211_scan_state next_scan_state;
 901	struct cfg80211_scan_request *scan_req;
 902
 903	lockdep_assert_wiphy(local->hw.wiphy);
 904
 905	/*
 906	 * check if at least one STA interface is associated,
 907	 * check if at least one STA interface has pending tx frames
 908	 * and grab the lowest used beacon interval
 909	 */
 
 910	list_for_each_entry(sdata, &local->interfaces, list) {
 911		if (!ieee80211_sdata_running(sdata))
 912			continue;
 913
 914		if (sdata->vif.type == NL80211_IFTYPE_STATION) {
 915			if (sdata->u.mgd.associated) {
 916				associated = true;
 917
 918				if (!qdisc_all_tx_empty(sdata->dev)) {
 919					tx_empty = false;
 920					break;
 921				}
 922			}
 923		}
 924	}
 
 925
 926	scan_req = rcu_dereference_protected(local->scan_req,
 927					     lockdep_is_held(&local->hw.wiphy->mtx));
 928
 929	next_chan = scan_req->channels[local->scan_channel_idx];
 930
 931	/*
 932	 * we're currently scanning a different channel, let's
 933	 * see if we can scan another channel without interfering
 934	 * with the current traffic situation.
 935	 *
 936	 * Keep good latency, do not stay off-channel more than 125 ms.
 937	 */
 938
 939	bad_latency = time_after(jiffies +
 940				 ieee80211_scan_get_channel_time(next_chan),
 941				 local->leave_oper_channel_time + HZ / 8);
 942
 943	if (associated && !tx_empty) {
 944		if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY)
 945			next_scan_state = SCAN_ABORT;
 946		else
 947			next_scan_state = SCAN_SUSPEND;
 948	} else if (associated && bad_latency) {
 949		next_scan_state = SCAN_SUSPEND;
 950	} else {
 951		next_scan_state = SCAN_SET_CHANNEL;
 952	}
 953
 954	local->next_scan_state = next_scan_state;
 955
 956	*next_delay = 0;
 957}
 958
 959static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
 960					     unsigned long *next_delay)
 961{
 962	int skip;
 963	struct ieee80211_channel *chan;
 
 964	struct cfg80211_scan_request *scan_req;
 965
 966	scan_req = rcu_dereference_protected(local->scan_req,
 967					     lockdep_is_held(&local->hw.wiphy->mtx));
 968
 969	skip = 0;
 970	chan = scan_req->channels[local->scan_channel_idx];
 971
 972	local->scan_chandef.chan = chan;
 973	local->scan_chandef.center_freq1 = chan->center_freq;
 974	local->scan_chandef.freq1_offset = chan->freq_offset;
 975	local->scan_chandef.center_freq2 = 0;
 976
 977	/* For scanning on the S1G band, detect the channel width according to
 978	 * the channel being scanned.
 979	 */
 980	if (chan->band == NL80211_BAND_S1GHZ) {
 981		local->scan_chandef.width = ieee80211_s1g_channel_width(chan);
 982		goto set_channel;
 
 
 
 
 
 
 
 
 
 
 
 
 983	}
 984
 985	/* If scanning on oper channel, use whatever channel-type
 986	 * is currently in use.
 987	 */
 988	if (chan == local->hw.conf.chandef.chan)
 989		local->scan_chandef = local->hw.conf.chandef;
 990	else
 991		local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
 992
 993set_channel:
 994	if (ieee80211_hw_conf_chan(local))
 995		skip = 1;
 996
 997	/* advance state machine to next channel/band */
 998	local->scan_channel_idx++;
 999
1000	if (skip) {
1001		/* if we skip this channel return to the decision state */
1002		local->next_scan_state = SCAN_DECISION;
1003		return;
1004	}
1005
1006	/*
1007	 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
1008	 * (which unfortunately doesn't say _why_ step a) is done,
1009	 * but it waits for the probe delay or until a frame is
1010	 * received - and the received frame would update the NAV).
1011	 * For now, we do not support waiting until a frame is
1012	 * received.
1013	 *
1014	 * In any case, it is not necessary for a passive scan.
1015	 */
1016	if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) ||
1017	    !scan_req->n_ssids) {
1018		*next_delay = max(msecs_to_jiffies(scan_req->duration),
1019				  IEEE80211_PASSIVE_CHANNEL_TIME);
1020		local->next_scan_state = SCAN_DECISION;
1021		if (scan_req->n_ssids)
1022			set_bit(SCAN_BEACON_WAIT, &local->scanning);
1023		return;
1024	}
1025
1026	/* active scan, send probes */
1027	*next_delay = IEEE80211_PROBE_DELAY;
1028	local->next_scan_state = SCAN_SEND_PROBE;
1029}
1030
1031static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
1032					 unsigned long *next_delay)
1033{
1034	/* switch back to the operating channel */
1035	local->scan_chandef.chan = NULL;
1036	ieee80211_hw_conf_chan(local);
1037
1038	/* disable PS */
1039	ieee80211_offchannel_return(local);
1040
1041	*next_delay = HZ / 5;
1042	/* afterwards, resume scan & go to next channel */
1043	local->next_scan_state = SCAN_RESUME;
1044}
1045
1046static void ieee80211_scan_state_resume(struct ieee80211_local *local,
1047					unsigned long *next_delay)
1048{
1049	ieee80211_offchannel_stop_vifs(local);
1050
1051	if (local->ops->flush) {
1052		ieee80211_flush_queues(local, NULL, false);
1053		*next_delay = 0;
1054	} else
1055		*next_delay = HZ / 10;
1056
1057	/* remember when we left the operating channel */
1058	local->leave_oper_channel_time = jiffies;
1059
1060	/* advance to the next channel to be scanned */
1061	local->next_scan_state = SCAN_SET_CHANNEL;
1062}
1063
1064void ieee80211_scan_work(struct wiphy *wiphy, struct wiphy_work *work)
1065{
1066	struct ieee80211_local *local =
1067		container_of(work, struct ieee80211_local, scan_work.work);
1068	struct ieee80211_sub_if_data *sdata;
1069	struct cfg80211_scan_request *scan_req;
1070	unsigned long next_delay = 0;
1071	bool aborted;
1072
1073	lockdep_assert_wiphy(local->hw.wiphy);
1074
1075	if (!ieee80211_can_run_worker(local)) {
1076		aborted = true;
1077		goto out_complete;
1078	}
1079
1080	sdata = rcu_dereference_protected(local->scan_sdata,
1081					  lockdep_is_held(&local->hw.wiphy->mtx));
1082	scan_req = rcu_dereference_protected(local->scan_req,
1083					     lockdep_is_held(&local->hw.wiphy->mtx));
1084
1085	/* When scanning on-channel, the first-callback means completed. */
1086	if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) {
1087		aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
1088		goto out_complete;
1089	}
1090
1091	if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) {
1092		aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
1093		goto out_complete;
1094	}
1095
1096	if (!sdata || !scan_req)
1097		return;
1098
1099	if (!local->scanning) {
1100		int rc;
1101
1102		RCU_INIT_POINTER(local->scan_req, NULL);
1103		RCU_INIT_POINTER(local->scan_sdata, NULL);
1104
1105		rc = __ieee80211_start_scan(sdata, scan_req);
1106		if (!rc)
1107			return;
1108		/* need to complete scan in cfg80211 */
1109		rcu_assign_pointer(local->scan_req, scan_req);
1110		aborted = true;
1111		goto out_complete;
 
1112	}
1113
1114	clear_bit(SCAN_BEACON_WAIT, &local->scanning);
1115
1116	/*
1117	 * as long as no delay is required advance immediately
1118	 * without scheduling a new work
1119	 */
1120	do {
1121		if (!ieee80211_sdata_running(sdata)) {
1122			aborted = true;
1123			goto out_complete;
1124		}
1125
1126		if (test_and_clear_bit(SCAN_BEACON_DONE, &local->scanning) &&
1127		    local->next_scan_state == SCAN_DECISION)
1128			local->next_scan_state = SCAN_SEND_PROBE;
1129
1130		switch (local->next_scan_state) {
1131		case SCAN_DECISION:
1132			/* if no more bands/channels left, complete scan */
1133			if (local->scan_channel_idx >= scan_req->n_channels) {
1134				aborted = false;
1135				goto out_complete;
1136			}
1137			ieee80211_scan_state_decision(local, &next_delay);
1138			break;
1139		case SCAN_SET_CHANNEL:
1140			ieee80211_scan_state_set_channel(local, &next_delay);
1141			break;
1142		case SCAN_SEND_PROBE:
1143			ieee80211_scan_state_send_probe(local, &next_delay);
1144			break;
1145		case SCAN_SUSPEND:
1146			ieee80211_scan_state_suspend(local, &next_delay);
1147			break;
1148		case SCAN_RESUME:
1149			ieee80211_scan_state_resume(local, &next_delay);
1150			break;
1151		case SCAN_ABORT:
1152			aborted = true;
1153			goto out_complete;
1154		}
1155	} while (next_delay == 0);
1156
1157	wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work,
1158				 next_delay);
1159	return;
1160
1161out_complete:
1162	__ieee80211_scan_completed(&local->hw, aborted);
 
 
1163}
1164
1165int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
1166			   struct cfg80211_scan_request *req)
1167{
1168	lockdep_assert_wiphy(sdata->local->hw.wiphy);
 
 
 
 
1169
1170	return __ieee80211_start_scan(sdata, req);
1171}
1172
1173int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
1174				const u8 *ssid, u8 ssid_len,
1175				struct ieee80211_channel **channels,
1176				unsigned int n_channels)
 
1177{
1178	struct ieee80211_local *local = sdata->local;
1179	int i, n_ch = 0;
1180	enum nl80211_band band;
1181
1182	lockdep_assert_wiphy(local->hw.wiphy);
1183
1184	/* busy scanning */
1185	if (local->scan_req)
1186		return -EBUSY;
1187
1188	/* fill internal scan request */
1189	if (!channels) {
1190		int max_n;
1191
1192		for (band = 0; band < NUM_NL80211_BANDS; band++) {
1193			if (!local->hw.wiphy->bands[band] ||
1194			    band == NL80211_BAND_6GHZ)
1195				continue;
1196
1197			max_n = local->hw.wiphy->bands[band]->n_channels;
1198			for (i = 0; i < max_n; i++) {
1199				struct ieee80211_channel *tmp_ch =
1200				    &local->hw.wiphy->bands[band]->channels[i];
1201
1202				if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR |
1203						     IEEE80211_CHAN_DISABLED) ||
1204				    !cfg80211_wdev_channel_allowed(&sdata->wdev,
1205								   tmp_ch))
1206					continue;
1207
1208				local->int_scan_req->channels[n_ch] = tmp_ch;
1209				n_ch++;
1210			}
1211		}
1212
1213		if (WARN_ON_ONCE(n_ch == 0))
1214			return -EINVAL;
1215
1216		local->int_scan_req->n_channels = n_ch;
1217	} else {
1218		for (i = 0; i < n_channels; i++) {
1219			if (channels[i]->flags & (IEEE80211_CHAN_NO_IR |
1220						  IEEE80211_CHAN_DISABLED) ||
1221			    !cfg80211_wdev_channel_allowed(&sdata->wdev,
1222							   channels[i]))
1223				continue;
1224
1225			local->int_scan_req->channels[n_ch] = channels[i];
1226			n_ch++;
1227		}
1228
1229		if (n_ch == 0)
1230			return -EINVAL;
1231
1232		local->int_scan_req->n_channels = n_ch;
1233	}
1234
1235	local->int_scan_req->ssids = &local->scan_ssid;
1236	local->int_scan_req->n_ssids = 1;
 
1237	memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
1238	local->int_scan_req->ssids[0].ssid_len = ssid_len;
1239
1240	return __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
 
 
 
1241}
1242
 
 
 
1243void ieee80211_scan_cancel(struct ieee80211_local *local)
1244{
1245	/* ensure a new scan cannot be queued */
1246	lockdep_assert_wiphy(local->hw.wiphy);
1247
1248	/*
1249	 * We are canceling software scan, or deferred scan that was not
1250	 * yet really started (see __ieee80211_start_scan ).
1251	 *
1252	 * Regarding hardware scan:
1253	 * - we can not call  __ieee80211_scan_completed() as when
1254	 *   SCAN_HW_SCANNING bit is set this function change
1255	 *   local->hw_scan_req to operate on 5G band, what race with
1256	 *   driver which can use local->hw_scan_req
1257	 *
1258	 * - we can not cancel scan_work since driver can schedule it
1259	 *   by ieee80211_scan_completed(..., true) to finish scan
1260	 *
1261	 * Hence we only call the cancel_hw_scan() callback, but the low-level
1262	 * driver is still responsible for calling ieee80211_scan_completed()
1263	 * after the scan was completed/aborted.
1264	 */
1265
 
1266	if (!local->scan_req)
1267		return;
1268
1269	/*
1270	 * We have a scan running and the driver already reported completion,
1271	 * but the worker hasn't run yet or is stuck on the mutex - mark it as
1272	 * cancelled.
1273	 */
1274	if (test_bit(SCAN_HW_SCANNING, &local->scanning) &&
1275	    test_bit(SCAN_COMPLETED, &local->scanning)) {
1276		set_bit(SCAN_HW_CANCELLED, &local->scanning);
1277		return;
1278	}
1279
1280	if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
1281		/*
1282		 * Make sure that __ieee80211_scan_completed doesn't trigger a
1283		 * scan on another band.
1284		 */
1285		set_bit(SCAN_HW_CANCELLED, &local->scanning);
1286		if (local->ops->cancel_hw_scan)
1287			drv_cancel_hw_scan(local,
1288				rcu_dereference_protected(local->scan_sdata,
1289						lockdep_is_held(&local->hw.wiphy->mtx)));
1290		return;
1291	}
1292
1293	wiphy_delayed_work_cancel(local->hw.wiphy, &local->scan_work);
 
 
 
 
 
1294	/* and clean up */
1295	memset(&local->scan_info, 0, sizeof(local->scan_info));
1296	__ieee80211_scan_completed(&local->hw, true);
 
 
1297}
1298
1299int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1300					struct cfg80211_sched_scan_request *req)
1301{
1302	struct ieee80211_local *local = sdata->local;
1303	struct ieee80211_scan_ies sched_scan_ies = {};
1304	struct cfg80211_chan_def chandef;
1305	int ret, i, iebufsz, num_bands = 0;
1306	u32 rate_masks[NUM_NL80211_BANDS] = {};
1307	u8 bands_used = 0;
1308	u8 *ie;
1309	u32 flags = 0;
1310
1311	lockdep_assert_wiphy(local->hw.wiphy);
1312
1313	iebufsz = local->scan_ies_len + req->ie_len;
1314
 
 
1315	if (!local->ops->sched_scan_start)
1316		return -EOPNOTSUPP;
1317
1318	for (i = 0; i < NUM_NL80211_BANDS; i++) {
1319		if (local->hw.wiphy->bands[i]) {
1320			bands_used |= BIT(i);
1321			rate_masks[i] = (u32) -1;
1322			num_bands++;
1323		}
1324	}
1325
1326	if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
1327		flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
1328
1329	ie = kcalloc(iebufsz, num_bands, GFP_KERNEL);
1330	if (!ie) {
1331		ret = -ENOMEM;
1332		goto out;
1333	}
1334
1335	ieee80211_prepare_scan_chandef(&chandef);
1336
1337	ret = ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz,
1338				       &sched_scan_ies, req->ie,
1339				       req->ie_len, bands_used, rate_masks,
1340				       &chandef, flags);
1341	if (ret < 0)
1342		goto error;
1343
1344	ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
1345	if (ret == 0) {
1346		rcu_assign_pointer(local->sched_scan_sdata, sdata);
1347		rcu_assign_pointer(local->sched_scan_req, req);
1348	}
1349
1350error:
1351	kfree(ie);
 
1352out:
1353	if (ret) {
1354		/* Clean in case of failure after HW restart or upon resume. */
1355		RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1356		RCU_INIT_POINTER(local->sched_scan_req, NULL);
1357	}
1358
1359	return ret;
1360}
1361
1362int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1363				       struct cfg80211_sched_scan_request *req)
1364{
1365	struct ieee80211_local *local = sdata->local;
 
1366
1367	lockdep_assert_wiphy(local->hw.wiphy);
1368
1369	if (rcu_access_pointer(local->sched_scan_sdata))
 
1370		return -EBUSY;
 
 
 
1371
1372	return __ieee80211_request_sched_scan_start(sdata, req);
 
1373}
1374
1375int ieee80211_request_sched_scan_stop(struct ieee80211_local *local)
1376{
1377	struct ieee80211_sub_if_data *sched_scan_sdata;
1378	int ret = -ENOENT;
1379
1380	lockdep_assert_wiphy(local->hw.wiphy);
1381
1382	if (!local->ops->sched_scan_stop)
1383		return -EOPNOTSUPP;
 
 
1384
1385	/* We don't want to restart sched scan anymore. */
1386	RCU_INIT_POINTER(local->sched_scan_req, NULL);
1387
1388	sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata,
1389						lockdep_is_held(&local->hw.wiphy->mtx));
1390	if (sched_scan_sdata) {
1391		ret = drv_sched_scan_stop(local, sched_scan_sdata);
1392		if (!ret)
1393			RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1394	}
 
 
1395
1396	return ret;
1397}
1398
1399void ieee80211_sched_scan_results(struct ieee80211_hw *hw)
1400{
1401	struct ieee80211_local *local = hw_to_local(hw);
1402
1403	trace_api_sched_scan_results(local);
1404
1405	cfg80211_sched_scan_results(hw->wiphy, 0);
1406}
1407EXPORT_SYMBOL(ieee80211_sched_scan_results);
1408
1409void ieee80211_sched_scan_end(struct ieee80211_local *local)
1410{
1411	lockdep_assert_wiphy(local->hw.wiphy);
1412
1413	if (!rcu_access_pointer(local->sched_scan_sdata))
 
1414		return;
 
1415
1416	RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1417
1418	/* If sched scan was aborted by the driver. */
1419	RCU_INIT_POINTER(local->sched_scan_req, NULL);
1420
1421	cfg80211_sched_scan_stopped_locked(local->hw.wiphy, 0);
 
 
1422}
1423
1424void ieee80211_sched_scan_stopped_work(struct wiphy *wiphy,
1425				       struct wiphy_work *work)
1426{
1427	struct ieee80211_local *local =
1428		container_of(work, struct ieee80211_local,
1429			     sched_scan_stopped_work);
1430
1431	ieee80211_sched_scan_end(local);
1432}
1433
1434void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
1435{
1436	struct ieee80211_local *local = hw_to_local(hw);
1437
1438	trace_api_sched_scan_stopped(local);
1439
1440	/*
1441	 * this shouldn't really happen, so for simplicity
1442	 * simply ignore it, and let mac80211 reconfigure
1443	 * the sched scan later on.
1444	 */
1445	if (local->in_reconfig)
1446		return;
1447
1448	wiphy_work_queue(hw->wiphy, &local->sched_scan_stopped_work);
1449}
1450EXPORT_SYMBOL(ieee80211_sched_scan_stopped);
v4.17
 
   1/*
   2 * Scanning implementation
   3 *
   4 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.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 2013-2015  Intel Mobile Communications GmbH
  10 * Copyright 2016-2017  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/if_arp.h>
  18#include <linux/etherdevice.h>
  19#include <linux/rtnetlink.h>
  20#include <net/sch_generic.h>
  21#include <linux/slab.h>
  22#include <linux/export.h>
 
  23#include <net/mac80211.h>
  24
  25#include "ieee80211_i.h"
  26#include "driver-ops.h"
  27#include "mesh.h"
  28
  29#define IEEE80211_PROBE_DELAY (HZ / 33)
  30#define IEEE80211_CHANNEL_TIME (HZ / 33)
  31#define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 9)
  32
  33void ieee80211_rx_bss_put(struct ieee80211_local *local,
  34			  struct ieee80211_bss *bss)
  35{
  36	if (!bss)
  37		return;
  38	cfg80211_put_bss(local->hw.wiphy,
  39			 container_of((void *)bss, struct cfg80211_bss, priv));
  40}
  41
  42static bool is_uapsd_supported(struct ieee802_11_elems *elems)
  43{
  44	u8 qos_info;
  45
  46	if (elems->wmm_info && elems->wmm_info_len == 7
  47	    && elems->wmm_info[5] == 1)
  48		qos_info = elems->wmm_info[6];
  49	else if (elems->wmm_param && elems->wmm_param_len == 24
  50		 && elems->wmm_param[5] == 1)
  51		qos_info = elems->wmm_param[6];
  52	else
  53		/* no valid wmm information or parameter element found */
  54		return false;
  55
  56	return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD;
  57}
  58
  59struct ieee80211_bss *
  60ieee80211_bss_info_update(struct ieee80211_local *local,
  61			  struct ieee80211_rx_status *rx_status,
  62			  struct ieee80211_mgmt *mgmt, size_t len,
  63			  struct ieee802_11_elems *elems,
  64			  struct ieee80211_channel *channel)
  65{
  66	bool beacon = ieee80211_is_beacon(mgmt->frame_control);
  67	struct cfg80211_bss *cbss;
  68	struct ieee80211_bss *bss;
 
 
 
 
 
  69	int clen, srlen;
  70	struct cfg80211_inform_bss bss_meta = {
  71		.boottime_ns = rx_status->boottime_ns,
  72	};
  73	bool signal_valid;
  74	struct ieee80211_sub_if_data *scan_sdata;
  75
  76	if (rx_status->flag & RX_FLAG_NO_SIGNAL_VAL)
  77		bss_meta.signal = 0; /* invalid signal indication */
  78	else if (ieee80211_hw_check(&local->hw, SIGNAL_DBM))
  79		bss_meta.signal = rx_status->signal * 100;
  80	else if (ieee80211_hw_check(&local->hw, SIGNAL_UNSPEC))
  81		bss_meta.signal = (rx_status->signal * 100) / local->hw.max_signal;
  82
  83	bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_20;
  84	if (rx_status->bw == RATE_INFO_BW_5)
  85		bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_5;
  86	else if (rx_status->bw == RATE_INFO_BW_10)
  87		bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_10;
  88
  89	bss_meta.chan = channel;
  90
  91	rcu_read_lock();
  92	scan_sdata = rcu_dereference(local->scan_sdata);
  93	if (scan_sdata && scan_sdata->vif.type == NL80211_IFTYPE_STATION &&
  94	    scan_sdata->vif.bss_conf.assoc &&
  95	    ieee80211_have_rx_timestamp(rx_status)) {
  96		bss_meta.parent_tsf =
  97			ieee80211_calculate_rx_timestamp(local, rx_status,
  98							 len + FCS_LEN, 24);
  99		ether_addr_copy(bss_meta.parent_bssid,
 100				scan_sdata->vif.bss_conf.bssid);
 101	}
 102	rcu_read_unlock();
 103
 104	cbss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta,
 105					      mgmt, len, GFP_ATOMIC);
 106	if (!cbss)
 107		return NULL;
 108	/* In case the signal is invalid update the status */
 109	signal_valid = abs(channel->center_freq - cbss->channel->center_freq)
 110		<= local->hw.wiphy->max_adj_channel_rssi_comp;
 111	if (!signal_valid)
 112		rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL;
 113
 114	bss = (void *)cbss->priv;
 115
 116	if (beacon)
 117		bss->device_ts_beacon = rx_status->device_timestamp;
 118	else
 119		bss->device_ts_presp = rx_status->device_timestamp;
 120
 121	if (elems->parse_error) {
 122		if (beacon)
 123			bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON;
 124		else
 125			bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP;
 126	} else {
 127		if (beacon)
 128			bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON;
 129		else
 130			bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP;
 131	}
 132
 133	/* save the ERP value so that it is available at association time */
 134	if (elems->erp_info && (!elems->parse_error ||
 135				!(bss->valid_data & IEEE80211_BSS_VALID_ERP))) {
 136		bss->erp_value = elems->erp_info[0];
 137		bss->has_erp_value = true;
 138		if (!elems->parse_error)
 139			bss->valid_data |= IEEE80211_BSS_VALID_ERP;
 140	}
 141
 142	/* replace old supported rates if we get new values */
 143	if (!elems->parse_error ||
 144	    !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) {
 145		srlen = 0;
 146		if (elems->supp_rates) {
 147			clen = IEEE80211_MAX_SUPP_RATES;
 148			if (clen > elems->supp_rates_len)
 149				clen = elems->supp_rates_len;
 150			memcpy(bss->supp_rates, elems->supp_rates, clen);
 151			srlen += clen;
 152		}
 153		if (elems->ext_supp_rates) {
 154			clen = IEEE80211_MAX_SUPP_RATES - srlen;
 155			if (clen > elems->ext_supp_rates_len)
 156				clen = elems->ext_supp_rates_len;
 157			memcpy(bss->supp_rates + srlen, elems->ext_supp_rates,
 158			       clen);
 159			srlen += clen;
 160		}
 161		if (srlen) {
 162			bss->supp_rates_len = srlen;
 163			if (!elems->parse_error)
 164				bss->valid_data |= IEEE80211_BSS_VALID_RATES;
 165		}
 166	}
 167
 168	if (!elems->parse_error ||
 169	    !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) {
 170		bss->wmm_used = elems->wmm_param || elems->wmm_info;
 171		bss->uapsd_supported = is_uapsd_supported(elems);
 172		if (!elems->parse_error)
 173			bss->valid_data |= IEEE80211_BSS_VALID_WMM;
 174	}
 175
 176	if (beacon) {
 177		struct ieee80211_supported_band *sband =
 178			local->hw.wiphy->bands[rx_status->band];
 179		if (!(rx_status->encoding == RX_ENC_HT) &&
 180		    !(rx_status->encoding == RX_ENC_VHT))
 181			bss->beacon_rate =
 182				&sband->bitrates[rx_status->rate_idx];
 183	}
 184
 185	return bss;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 186}
 187
 188static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata,
 
 189					u32 scan_flags, const u8 *da)
 190{
 191	if (!sdata)
 192		return false;
 193	/* accept broadcast for OCE */
 194	if (scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP &&
 195	    is_broadcast_ether_addr(da))
 
 
 196		return true;
 
 197	if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
 198		return true;
 199	return ether_addr_equal(da, sdata->vif.addr);
 200}
 201
 202void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb)
 203{
 204	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
 205	struct ieee80211_sub_if_data *sdata1, *sdata2;
 206	struct ieee80211_mgmt *mgmt = (void *)skb->data;
 207	struct ieee80211_bss *bss;
 208	u8 *elements;
 209	struct ieee80211_channel *channel;
 210	size_t baselen;
 211	struct ieee802_11_elems elems;
 212
 213	if (skb->len < 24 ||
 214	    (!ieee80211_is_probe_resp(mgmt->frame_control) &&
 215	     !ieee80211_is_beacon(mgmt->frame_control)))
 216		return;
 217
 218	sdata1 = rcu_dereference(local->scan_sdata);
 219	sdata2 = rcu_dereference(local->sched_scan_sdata);
 
 
 
 
 
 
 220
 221	if (likely(!sdata1 && !sdata2))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 222		return;
 223
 224	if (ieee80211_is_probe_resp(mgmt->frame_control)) {
 
 225		struct cfg80211_scan_request *scan_req;
 226		struct cfg80211_sched_scan_request *sched_scan_req;
 227		u32 scan_req_flags = 0, sched_scan_req_flags = 0;
 228
 
 
 
 
 
 
 229		scan_req = rcu_dereference(local->scan_req);
 230		sched_scan_req = rcu_dereference(local->sched_scan_req);
 231
 232		if (scan_req)
 233			scan_req_flags = scan_req->flags;
 234
 235		if (sched_scan_req)
 236			sched_scan_req_flags = sched_scan_req->flags;
 237
 238		/* ignore ProbeResp to foreign address or non-bcast (OCE)
 239		 * unless scanning with randomised address
 240		 */
 241		if (!ieee80211_scan_accept_presp(sdata1, scan_req_flags,
 
 242						 mgmt->da) &&
 243		    !ieee80211_scan_accept_presp(sdata2, sched_scan_req_flags,
 
 244						 mgmt->da))
 245			return;
 246
 247		elements = mgmt->u.probe_resp.variable;
 248		baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable);
 249	} else {
 250		baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable);
 251		elements = mgmt->u.beacon.variable;
 
 252	}
 253
 254	if (baselen > skb->len)
 255		return;
 256
 257	ieee802_11_parse_elems(elements, skb->len - baselen, false, &elems);
 258
 259	channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
 260
 261	if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 262		return;
 263
 264	bss = ieee80211_bss_info_update(local, rx_status,
 265					mgmt, skb->len, &elems,
 266					channel);
 267	if (bss)
 268		ieee80211_rx_bss_put(local, bss);
 269}
 270
 271static void
 272ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef,
 273			       enum nl80211_bss_scan_width scan_width)
 274{
 275	memset(chandef, 0, sizeof(*chandef));
 276	switch (scan_width) {
 277	case NL80211_BSS_CHAN_WIDTH_5:
 278		chandef->width = NL80211_CHAN_WIDTH_5;
 279		break;
 280	case NL80211_BSS_CHAN_WIDTH_10:
 281		chandef->width = NL80211_CHAN_WIDTH_10;
 282		break;
 283	default:
 284		chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
 285		break;
 286	}
 287}
 288
 289/* return false if no more work */
 290static bool ieee80211_prep_hw_scan(struct ieee80211_local *local)
 291{
 
 292	struct cfg80211_scan_request *req;
 293	struct cfg80211_chan_def chandef;
 294	u8 bands_used = 0;
 295	int i, ielen, n_chans;
 
 
 296
 297	req = rcu_dereference_protected(local->scan_req,
 298					lockdep_is_held(&local->mtx));
 299
 300	if (test_bit(SCAN_HW_CANCELLED, &local->scanning))
 301		return false;
 302
 303	if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
 
 
 304		for (i = 0; i < req->n_channels; i++) {
 305			local->hw_scan_req->req.channels[i] = req->channels[i];
 306			bands_used |= BIT(req->channels[i]->band);
 307		}
 308
 309		n_chans = req->n_channels;
 310	} else {
 311		do {
 312			if (local->hw_scan_band == NUM_NL80211_BANDS)
 313				return false;
 314
 315			n_chans = 0;
 
 316
 317			for (i = 0; i < req->n_channels; i++) {
 318				if (req->channels[i]->band !=
 319				    local->hw_scan_band)
 320					continue;
 321				local->hw_scan_req->req.channels[n_chans] =
 322							req->channels[i];
 323				n_chans++;
 324				bands_used |= BIT(req->channels[i]->band);
 325			}
 326
 327			local->hw_scan_band++;
 328		} while (!n_chans);
 329	}
 330
 331	local->hw_scan_req->req.n_channels = n_chans;
 332	ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
 333
 334	ielen = ieee80211_build_preq_ies(local,
 
 
 
 335					 (u8 *)local->hw_scan_req->req.ie,
 336					 local->hw_scan_ies_bufsize,
 337					 &local->hw_scan_req->ies,
 338					 req->ie, req->ie_len,
 339					 bands_used, req->rates, &chandef);
 
 
 
 340	local->hw_scan_req->req.ie_len = ielen;
 341	local->hw_scan_req->req.no_cck = req->no_cck;
 342	ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr);
 343	ether_addr_copy(local->hw_scan_req->req.mac_addr_mask,
 344			req->mac_addr_mask);
 345	ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid);
 346
 347	return true;
 348}
 349
 350static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
 351{
 352	struct ieee80211_local *local = hw_to_local(hw);
 353	bool hw_scan = local->ops->hw_scan;
 354	bool was_scanning = local->scanning;
 355	struct cfg80211_scan_request *scan_req;
 356	struct ieee80211_sub_if_data *scan_sdata;
 357	struct ieee80211_sub_if_data *sdata;
 358
 359	lockdep_assert_held(&local->mtx);
 360
 361	/*
 362	 * It's ok to abort a not-yet-running scan (that
 363	 * we have one at all will be verified by checking
 364	 * local->scan_req next), but not to complete it
 365	 * successfully.
 366	 */
 367	if (WARN_ON(!local->scanning && !aborted))
 368		aborted = true;
 369
 370	if (WARN_ON(!local->scan_req))
 371		return;
 372
 
 
 
 373	if (hw_scan && !aborted &&
 374	    !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) &&
 375	    ieee80211_prep_hw_scan(local)) {
 376		int rc;
 377
 378		rc = drv_hw_scan(local,
 379			rcu_dereference_protected(local->scan_sdata,
 380						  lockdep_is_held(&local->mtx)),
 381			local->hw_scan_req);
 382
 383		if (rc == 0)
 384			return;
 385
 386		/* HW scan failed and is going to be reported as aborted,
 387		 * so clear old scan info.
 388		 */
 389		memset(&local->scan_info, 0, sizeof(local->scan_info));
 390		aborted = true;
 391	}
 392
 393	kfree(local->hw_scan_req);
 394	local->hw_scan_req = NULL;
 395
 396	scan_req = rcu_dereference_protected(local->scan_req,
 397					     lockdep_is_held(&local->mtx));
 398
 399	if (scan_req != local->int_scan_req) {
 400		local->scan_info.aborted = aborted;
 401		cfg80211_scan_done(scan_req, &local->scan_info);
 402	}
 403	RCU_INIT_POINTER(local->scan_req, NULL);
 404
 405	scan_sdata = rcu_dereference_protected(local->scan_sdata,
 406					       lockdep_is_held(&local->mtx));
 407	RCU_INIT_POINTER(local->scan_sdata, NULL);
 408
 409	local->scanning = 0;
 410	local->scan_chandef.chan = NULL;
 411
 
 
 
 
 
 
 
 412	/* Set power back to normal operating levels. */
 413	ieee80211_hw_config(local, 0);
 414
 415	if (!hw_scan) {
 416		ieee80211_configure_filter(local);
 417		drv_sw_scan_complete(local, scan_sdata);
 418		ieee80211_offchannel_return(local);
 419	}
 420
 421	ieee80211_recalc_idle(local);
 422
 423	ieee80211_mlme_notify_scan_completed(local);
 424	ieee80211_ibss_notify_scan_completed(local);
 425
 426	/* Requeue all the work that might have been ignored while
 427	 * the scan was in progress; if there was none this will
 428	 * just be a no-op for the particular interface.
 429	 */
 430	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 431		if (ieee80211_sdata_running(sdata))
 432			ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 433	}
 434
 435	if (was_scanning)
 436		ieee80211_start_next_roc(local);
 437}
 438
 439void ieee80211_scan_completed(struct ieee80211_hw *hw,
 440			      struct cfg80211_scan_info *info)
 441{
 442	struct ieee80211_local *local = hw_to_local(hw);
 443
 444	trace_api_scan_completed(local, info->aborted);
 445
 446	set_bit(SCAN_COMPLETED, &local->scanning);
 447	if (info->aborted)
 448		set_bit(SCAN_ABORTED, &local->scanning);
 449
 450	memcpy(&local->scan_info, info, sizeof(*info));
 451
 452	ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
 453}
 454EXPORT_SYMBOL(ieee80211_scan_completed);
 455
 456static int ieee80211_start_sw_scan(struct ieee80211_local *local,
 457				   struct ieee80211_sub_if_data *sdata)
 458{
 459	/* Software scan is not supported in multi-channel cases */
 460	if (local->use_chanctx)
 461		return -EOPNOTSUPP;
 462
 463	/*
 464	 * Hardware/driver doesn't support hw_scan, so use software
 465	 * scanning instead. First send a nullfunc frame with power save
 466	 * bit on so that AP will buffer the frames for us while we are not
 467	 * listening, then send probe requests to each channel and wait for
 468	 * the responses. After all channels are scanned, tune back to the
 469	 * original channel and send a nullfunc frame with power save bit
 470	 * off to trigger the AP to send us all the buffered frames.
 471	 *
 472	 * Note that while local->sw_scanning is true everything else but
 473	 * nullfunc frames and probe requests will be dropped in
 474	 * ieee80211_tx_h_check_assoc().
 475	 */
 476	drv_sw_scan_start(local, sdata, local->scan_addr);
 477
 478	local->leave_oper_channel_time = jiffies;
 479	local->next_scan_state = SCAN_DECISION;
 480	local->scan_channel_idx = 0;
 481
 482	ieee80211_offchannel_stop_vifs(local);
 483
 484	/* ensure nullfunc is transmitted before leaving operating channel */
 485	ieee80211_flush_queues(local, NULL, false);
 486
 487	ieee80211_configure_filter(local);
 488
 489	/* We need to set power level at maximum rate for scanning. */
 490	ieee80211_hw_config(local, 0);
 491
 492	ieee80211_queue_delayed_work(&local->hw,
 493				     &local->scan_work, 0);
 494
 495	return 0;
 496}
 497
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 498static bool ieee80211_can_scan(struct ieee80211_local *local,
 499			       struct ieee80211_sub_if_data *sdata)
 500{
 501	if (ieee80211_is_radar_required(local))
 502		return false;
 503
 504	if (!list_empty(&local->roc_list))
 505		return false;
 506
 507	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
 508	    sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL)
 509		return false;
 510
 511	return true;
 512}
 513
 514void ieee80211_run_deferred_scan(struct ieee80211_local *local)
 515{
 516	lockdep_assert_held(&local->mtx);
 517
 518	if (!local->scan_req || local->scanning)
 519		return;
 520
 521	if (!ieee80211_can_scan(local,
 522				rcu_dereference_protected(
 523					local->scan_sdata,
 524					lockdep_is_held(&local->mtx))))
 525		return;
 526
 527	ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
 528				     round_jiffies_relative(0));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 529}
 530
 531static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
 532					    unsigned long *next_delay)
 533{
 534	int i;
 535	struct ieee80211_sub_if_data *sdata;
 536	struct cfg80211_scan_request *scan_req;
 537	enum nl80211_band band = local->hw.conf.chandef.chan->band;
 538	u32 tx_flags;
 539
 540	scan_req = rcu_dereference_protected(local->scan_req,
 541					     lockdep_is_held(&local->mtx));
 542
 543	tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
 544	if (scan_req->no_cck)
 545		tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
 
 
 
 
 546
 547	sdata = rcu_dereference_protected(local->scan_sdata,
 548					  lockdep_is_held(&local->mtx));
 549
 550	for (i = 0; i < scan_req->n_ssids; i++)
 551		ieee80211_send_probe_req(
 552			sdata, local->scan_addr, scan_req->bssid,
 553			scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len,
 554			scan_req->ie, scan_req->ie_len,
 555			scan_req->rates[band], false,
 556			tx_flags, local->hw.conf.chandef.chan, true);
 557
 558	/*
 559	 * After sending probe requests, wait for probe responses
 560	 * on the channel.
 561	 */
 562	*next_delay = IEEE80211_CHANNEL_TIME;
 
 
 
 563	local->next_scan_state = SCAN_DECISION;
 564}
 565
 566static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
 567				  struct cfg80211_scan_request *req)
 568{
 569	struct ieee80211_local *local = sdata->local;
 
 570	int rc;
 571
 572	lockdep_assert_held(&local->mtx);
 573
 574	if (local->scan_req || ieee80211_is_radar_required(local))
 
 
 
 
 
 
 
 
 
 
 575		return -EBUSY;
 576
 577	if (!ieee80211_can_scan(local, sdata)) {
 578		/* wait for the work to finish/time out */
 579		rcu_assign_pointer(local->scan_req, req);
 580		rcu_assign_pointer(local->scan_sdata, sdata);
 581		return 0;
 582	}
 583
 584	if (local->ops->hw_scan) {
 
 585		u8 *ies;
 586
 587		local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len;
 588
 589		if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
 590			int i, n_bands = 0;
 591			u8 bands_counted = 0;
 592
 593			for (i = 0; i < req->n_channels; i++) {
 594				if (bands_counted & BIT(req->channels[i]->band))
 595					continue;
 596				bands_counted |= BIT(req->channels[i]->band);
 597				n_bands++;
 598			}
 599
 600			local->hw_scan_ies_bufsize *= n_bands;
 601		}
 602
 603		local->hw_scan_req = kmalloc(
 604				sizeof(*local->hw_scan_req) +
 605				req->n_channels * sizeof(req->channels[0]) +
 606				local->hw_scan_ies_bufsize, GFP_KERNEL);
 
 607		if (!local->hw_scan_req)
 608			return -ENOMEM;
 609
 610		local->hw_scan_req->req.ssids = req->ssids;
 611		local->hw_scan_req->req.n_ssids = req->n_ssids;
 
 
 
 
 
 612		ies = (u8 *)local->hw_scan_req +
 613			sizeof(*local->hw_scan_req) +
 614			req->n_channels * sizeof(req->channels[0]);
 615		local->hw_scan_req->req.ie = ies;
 616		local->hw_scan_req->req.flags = req->flags;
 617		eth_broadcast_addr(local->hw_scan_req->req.bssid);
 618		local->hw_scan_req->req.duration = req->duration;
 619		local->hw_scan_req->req.duration_mandatory =
 620			req->duration_mandatory;
 
 
 621
 622		local->hw_scan_band = 0;
 
 
 
 
 623
 624		/*
 625		 * After allocating local->hw_scan_req, we must
 626		 * go through until ieee80211_prep_hw_scan(), so
 627		 * anything that might be changed here and leave
 628		 * this function early must not go after this
 629		 * allocation.
 630		 */
 631	}
 632
 633	rcu_assign_pointer(local->scan_req, req);
 634	rcu_assign_pointer(local->scan_sdata, sdata);
 635
 636	if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
 637		get_random_mask_addr(local->scan_addr,
 638				     req->mac_addr,
 639				     req->mac_addr_mask);
 640	else
 641		memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN);
 642
 643	if (local->ops->hw_scan) {
 644		__set_bit(SCAN_HW_SCANNING, &local->scanning);
 645	} else if ((req->n_channels == 1) &&
 646		   (req->channels[0] == local->_oper_chandef.chan)) {
 647		/*
 648		 * If we are scanning only on the operating channel
 649		 * then we do not need to stop normal activities
 650		 */
 651		unsigned long next_delay;
 652
 653		__set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
 654
 655		ieee80211_recalc_idle(local);
 656
 657		/* Notify driver scan is starting, keep order of operations
 658		 * same as normal software scan, in case that matters. */
 659		drv_sw_scan_start(local, sdata, local->scan_addr);
 660
 661		ieee80211_configure_filter(local); /* accept probe-responses */
 662
 663		/* We need to ensure power level is at max for scanning. */
 664		ieee80211_hw_config(local, 0);
 665
 666		if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR |
 667						IEEE80211_CHAN_RADAR)) ||
 668		    !req->n_ssids) {
 669			next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
 
 
 670		} else {
 671			ieee80211_scan_state_send_probe(local, &next_delay);
 672			next_delay = IEEE80211_CHANNEL_TIME;
 673		}
 674
 675		/* Now, just wait a bit and we are all done! */
 676		ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
 677					     next_delay);
 678		return 0;
 679	} else {
 680		/* Do normal software scan */
 681		__set_bit(SCAN_SW_SCANNING, &local->scanning);
 682	}
 683
 684	ieee80211_recalc_idle(local);
 685
 686	if (local->ops->hw_scan) {
 687		WARN_ON(!ieee80211_prep_hw_scan(local));
 688		rc = drv_hw_scan(local, sdata, local->hw_scan_req);
 689	} else {
 690		rc = ieee80211_start_sw_scan(local, sdata);
 691	}
 692
 693	if (rc) {
 694		kfree(local->hw_scan_req);
 695		local->hw_scan_req = NULL;
 696		local->scanning = 0;
 697
 698		ieee80211_recalc_idle(local);
 699
 700		local->scan_req = NULL;
 701		RCU_INIT_POINTER(local->scan_sdata, NULL);
 702	}
 703
 
 
 
 
 
 
 
 
 
 
 
 
 704	return rc;
 705}
 706
 707static unsigned long
 708ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
 709{
 710	/*
 711	 * TODO: channel switching also consumes quite some time,
 712	 * add that delay as well to get a better estimation
 713	 */
 714	if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR))
 715		return IEEE80211_PASSIVE_CHANNEL_TIME;
 716	return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
 717}
 718
 719static void ieee80211_scan_state_decision(struct ieee80211_local *local,
 720					  unsigned long *next_delay)
 721{
 722	bool associated = false;
 723	bool tx_empty = true;
 724	bool bad_latency;
 725	struct ieee80211_sub_if_data *sdata;
 726	struct ieee80211_channel *next_chan;
 727	enum mac80211_scan_state next_scan_state;
 728	struct cfg80211_scan_request *scan_req;
 729
 
 
 730	/*
 731	 * check if at least one STA interface is associated,
 732	 * check if at least one STA interface has pending tx frames
 733	 * and grab the lowest used beacon interval
 734	 */
 735	mutex_lock(&local->iflist_mtx);
 736	list_for_each_entry(sdata, &local->interfaces, list) {
 737		if (!ieee80211_sdata_running(sdata))
 738			continue;
 739
 740		if (sdata->vif.type == NL80211_IFTYPE_STATION) {
 741			if (sdata->u.mgd.associated) {
 742				associated = true;
 743
 744				if (!qdisc_all_tx_empty(sdata->dev)) {
 745					tx_empty = false;
 746					break;
 747				}
 748			}
 749		}
 750	}
 751	mutex_unlock(&local->iflist_mtx);
 752
 753	scan_req = rcu_dereference_protected(local->scan_req,
 754					     lockdep_is_held(&local->mtx));
 755
 756	next_chan = scan_req->channels[local->scan_channel_idx];
 757
 758	/*
 759	 * we're currently scanning a different channel, let's
 760	 * see if we can scan another channel without interfering
 761	 * with the current traffic situation.
 762	 *
 763	 * Keep good latency, do not stay off-channel more than 125 ms.
 764	 */
 765
 766	bad_latency = time_after(jiffies +
 767				 ieee80211_scan_get_channel_time(next_chan),
 768				 local->leave_oper_channel_time + HZ / 8);
 769
 770	if (associated && !tx_empty) {
 771		if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY)
 772			next_scan_state = SCAN_ABORT;
 773		else
 774			next_scan_state = SCAN_SUSPEND;
 775	} else if (associated && bad_latency) {
 776		next_scan_state = SCAN_SUSPEND;
 777	} else {
 778		next_scan_state = SCAN_SET_CHANNEL;
 779	}
 780
 781	local->next_scan_state = next_scan_state;
 782
 783	*next_delay = 0;
 784}
 785
 786static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
 787					     unsigned long *next_delay)
 788{
 789	int skip;
 790	struct ieee80211_channel *chan;
 791	enum nl80211_bss_scan_width oper_scan_width;
 792	struct cfg80211_scan_request *scan_req;
 793
 794	scan_req = rcu_dereference_protected(local->scan_req,
 795					     lockdep_is_held(&local->mtx));
 796
 797	skip = 0;
 798	chan = scan_req->channels[local->scan_channel_idx];
 799
 800	local->scan_chandef.chan = chan;
 801	local->scan_chandef.center_freq1 = chan->center_freq;
 
 802	local->scan_chandef.center_freq2 = 0;
 803	switch (scan_req->scan_width) {
 804	case NL80211_BSS_CHAN_WIDTH_5:
 805		local->scan_chandef.width = NL80211_CHAN_WIDTH_5;
 806		break;
 807	case NL80211_BSS_CHAN_WIDTH_10:
 808		local->scan_chandef.width = NL80211_CHAN_WIDTH_10;
 809		break;
 810	case NL80211_BSS_CHAN_WIDTH_20:
 811		/* If scanning on oper channel, use whatever channel-type
 812		 * is currently in use.
 813		 */
 814		oper_scan_width = cfg80211_chandef_to_scan_width(
 815					&local->_oper_chandef);
 816		if (chan == local->_oper_chandef.chan &&
 817		    oper_scan_width == scan_req->scan_width)
 818			local->scan_chandef = local->_oper_chandef;
 819		else
 820			local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
 821		break;
 822	}
 823
 824	if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL))
 
 
 
 
 
 
 
 
 
 825		skip = 1;
 826
 827	/* advance state machine to next channel/band */
 828	local->scan_channel_idx++;
 829
 830	if (skip) {
 831		/* if we skip this channel return to the decision state */
 832		local->next_scan_state = SCAN_DECISION;
 833		return;
 834	}
 835
 836	/*
 837	 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
 838	 * (which unfortunately doesn't say _why_ step a) is done,
 839	 * but it waits for the probe delay or until a frame is
 840	 * received - and the received frame would update the NAV).
 841	 * For now, we do not support waiting until a frame is
 842	 * received.
 843	 *
 844	 * In any case, it is not necessary for a passive scan.
 845	 */
 846	if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) ||
 847	    !scan_req->n_ssids) {
 848		*next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
 
 849		local->next_scan_state = SCAN_DECISION;
 
 
 850		return;
 851	}
 852
 853	/* active scan, send probes */
 854	*next_delay = IEEE80211_PROBE_DELAY;
 855	local->next_scan_state = SCAN_SEND_PROBE;
 856}
 857
 858static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
 859					 unsigned long *next_delay)
 860{
 861	/* switch back to the operating channel */
 862	local->scan_chandef.chan = NULL;
 863	ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 864
 865	/* disable PS */
 866	ieee80211_offchannel_return(local);
 867
 868	*next_delay = HZ / 5;
 869	/* afterwards, resume scan & go to next channel */
 870	local->next_scan_state = SCAN_RESUME;
 871}
 872
 873static void ieee80211_scan_state_resume(struct ieee80211_local *local,
 874					unsigned long *next_delay)
 875{
 876	ieee80211_offchannel_stop_vifs(local);
 877
 878	if (local->ops->flush) {
 879		ieee80211_flush_queues(local, NULL, false);
 880		*next_delay = 0;
 881	} else
 882		*next_delay = HZ / 10;
 883
 884	/* remember when we left the operating channel */
 885	local->leave_oper_channel_time = jiffies;
 886
 887	/* advance to the next channel to be scanned */
 888	local->next_scan_state = SCAN_SET_CHANNEL;
 889}
 890
 891void ieee80211_scan_work(struct work_struct *work)
 892{
 893	struct ieee80211_local *local =
 894		container_of(work, struct ieee80211_local, scan_work.work);
 895	struct ieee80211_sub_if_data *sdata;
 896	struct cfg80211_scan_request *scan_req;
 897	unsigned long next_delay = 0;
 898	bool aborted;
 899
 900	mutex_lock(&local->mtx);
 901
 902	if (!ieee80211_can_run_worker(local)) {
 903		aborted = true;
 904		goto out_complete;
 905	}
 906
 907	sdata = rcu_dereference_protected(local->scan_sdata,
 908					  lockdep_is_held(&local->mtx));
 909	scan_req = rcu_dereference_protected(local->scan_req,
 910					     lockdep_is_held(&local->mtx));
 911
 912	/* When scanning on-channel, the first-callback means completed. */
 913	if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) {
 914		aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
 915		goto out_complete;
 916	}
 917
 918	if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) {
 919		aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
 920		goto out_complete;
 921	}
 922
 923	if (!sdata || !scan_req)
 924		goto out;
 925
 926	if (!local->scanning) {
 927		int rc;
 928
 929		RCU_INIT_POINTER(local->scan_req, NULL);
 930		RCU_INIT_POINTER(local->scan_sdata, NULL);
 931
 932		rc = __ieee80211_start_scan(sdata, scan_req);
 933		if (rc) {
 934			/* need to complete scan in cfg80211 */
 935			rcu_assign_pointer(local->scan_req, scan_req);
 936			aborted = true;
 937			goto out_complete;
 938		} else
 939			goto out;
 940	}
 941
 
 
 942	/*
 943	 * as long as no delay is required advance immediately
 944	 * without scheduling a new work
 945	 */
 946	do {
 947		if (!ieee80211_sdata_running(sdata)) {
 948			aborted = true;
 949			goto out_complete;
 950		}
 951
 
 
 
 
 952		switch (local->next_scan_state) {
 953		case SCAN_DECISION:
 954			/* if no more bands/channels left, complete scan */
 955			if (local->scan_channel_idx >= scan_req->n_channels) {
 956				aborted = false;
 957				goto out_complete;
 958			}
 959			ieee80211_scan_state_decision(local, &next_delay);
 960			break;
 961		case SCAN_SET_CHANNEL:
 962			ieee80211_scan_state_set_channel(local, &next_delay);
 963			break;
 964		case SCAN_SEND_PROBE:
 965			ieee80211_scan_state_send_probe(local, &next_delay);
 966			break;
 967		case SCAN_SUSPEND:
 968			ieee80211_scan_state_suspend(local, &next_delay);
 969			break;
 970		case SCAN_RESUME:
 971			ieee80211_scan_state_resume(local, &next_delay);
 972			break;
 973		case SCAN_ABORT:
 974			aborted = true;
 975			goto out_complete;
 976		}
 977	} while (next_delay == 0);
 978
 979	ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay);
 980	goto out;
 
 981
 982out_complete:
 983	__ieee80211_scan_completed(&local->hw, aborted);
 984out:
 985	mutex_unlock(&local->mtx);
 986}
 987
 988int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
 989			   struct cfg80211_scan_request *req)
 990{
 991	int res;
 992
 993	mutex_lock(&sdata->local->mtx);
 994	res = __ieee80211_start_scan(sdata, req);
 995	mutex_unlock(&sdata->local->mtx);
 996
 997	return res;
 998}
 999
1000int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
1001				const u8 *ssid, u8 ssid_len,
1002				struct ieee80211_channel **channels,
1003				unsigned int n_channels,
1004				enum nl80211_bss_scan_width scan_width)
1005{
1006	struct ieee80211_local *local = sdata->local;
1007	int ret = -EBUSY, i, n_ch = 0;
1008	enum nl80211_band band;
1009
1010	mutex_lock(&local->mtx);
1011
1012	/* busy scanning */
1013	if (local->scan_req)
1014		goto unlock;
1015
1016	/* fill internal scan request */
1017	if (!channels) {
1018		int max_n;
1019
1020		for (band = 0; band < NUM_NL80211_BANDS; band++) {
1021			if (!local->hw.wiphy->bands[band])
 
1022				continue;
1023
1024			max_n = local->hw.wiphy->bands[band]->n_channels;
1025			for (i = 0; i < max_n; i++) {
1026				struct ieee80211_channel *tmp_ch =
1027				    &local->hw.wiphy->bands[band]->channels[i];
1028
1029				if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR |
1030						     IEEE80211_CHAN_DISABLED))
 
 
1031					continue;
1032
1033				local->int_scan_req->channels[n_ch] = tmp_ch;
1034				n_ch++;
1035			}
1036		}
1037
1038		if (WARN_ON_ONCE(n_ch == 0))
1039			goto unlock;
1040
1041		local->int_scan_req->n_channels = n_ch;
1042	} else {
1043		for (i = 0; i < n_channels; i++) {
1044			if (channels[i]->flags & (IEEE80211_CHAN_NO_IR |
1045						  IEEE80211_CHAN_DISABLED))
 
 
1046				continue;
1047
1048			local->int_scan_req->channels[n_ch] = channels[i];
1049			n_ch++;
1050		}
1051
1052		if (WARN_ON_ONCE(n_ch == 0))
1053			goto unlock;
1054
1055		local->int_scan_req->n_channels = n_ch;
1056	}
1057
1058	local->int_scan_req->ssids = &local->scan_ssid;
1059	local->int_scan_req->n_ssids = 1;
1060	local->int_scan_req->scan_width = scan_width;
1061	memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
1062	local->int_scan_req->ssids[0].ssid_len = ssid_len;
1063
1064	ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
1065 unlock:
1066	mutex_unlock(&local->mtx);
1067	return ret;
1068}
1069
1070/*
1071 * Only call this function when a scan can't be queued -- under RTNL.
1072 */
1073void ieee80211_scan_cancel(struct ieee80211_local *local)
1074{
 
 
 
1075	/*
1076	 * We are canceling software scan, or deferred scan that was not
1077	 * yet really started (see __ieee80211_start_scan ).
1078	 *
1079	 * Regarding hardware scan:
1080	 * - we can not call  __ieee80211_scan_completed() as when
1081	 *   SCAN_HW_SCANNING bit is set this function change
1082	 *   local->hw_scan_req to operate on 5G band, what race with
1083	 *   driver which can use local->hw_scan_req
1084	 *
1085	 * - we can not cancel scan_work since driver can schedule it
1086	 *   by ieee80211_scan_completed(..., true) to finish scan
1087	 *
1088	 * Hence we only call the cancel_hw_scan() callback, but the low-level
1089	 * driver is still responsible for calling ieee80211_scan_completed()
1090	 * after the scan was completed/aborted.
1091	 */
1092
1093	mutex_lock(&local->mtx);
1094	if (!local->scan_req)
1095		goto out;
1096
1097	/*
1098	 * We have a scan running and the driver already reported completion,
1099	 * but the worker hasn't run yet or is stuck on the mutex - mark it as
1100	 * cancelled.
1101	 */
1102	if (test_bit(SCAN_HW_SCANNING, &local->scanning) &&
1103	    test_bit(SCAN_COMPLETED, &local->scanning)) {
1104		set_bit(SCAN_HW_CANCELLED, &local->scanning);
1105		goto out;
1106	}
1107
1108	if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
1109		/*
1110		 * Make sure that __ieee80211_scan_completed doesn't trigger a
1111		 * scan on another band.
1112		 */
1113		set_bit(SCAN_HW_CANCELLED, &local->scanning);
1114		if (local->ops->cancel_hw_scan)
1115			drv_cancel_hw_scan(local,
1116				rcu_dereference_protected(local->scan_sdata,
1117						lockdep_is_held(&local->mtx)));
1118		goto out;
1119	}
1120
1121	/*
1122	 * If the work is currently running, it must be blocked on
1123	 * the mutex, but we'll set scan_sdata = NULL and it'll
1124	 * simply exit once it acquires the mutex.
1125	 */
1126	cancel_delayed_work(&local->scan_work);
1127	/* and clean up */
1128	memset(&local->scan_info, 0, sizeof(local->scan_info));
1129	__ieee80211_scan_completed(&local->hw, true);
1130out:
1131	mutex_unlock(&local->mtx);
1132}
1133
1134int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1135					struct cfg80211_sched_scan_request *req)
1136{
1137	struct ieee80211_local *local = sdata->local;
1138	struct ieee80211_scan_ies sched_scan_ies = {};
1139	struct cfg80211_chan_def chandef;
1140	int ret, i, iebufsz, num_bands = 0;
1141	u32 rate_masks[NUM_NL80211_BANDS] = {};
1142	u8 bands_used = 0;
1143	u8 *ie;
 
 
 
1144
1145	iebufsz = local->scan_ies_len + req->ie_len;
1146
1147	lockdep_assert_held(&local->mtx);
1148
1149	if (!local->ops->sched_scan_start)
1150		return -ENOTSUPP;
1151
1152	for (i = 0; i < NUM_NL80211_BANDS; i++) {
1153		if (local->hw.wiphy->bands[i]) {
1154			bands_used |= BIT(i);
1155			rate_masks[i] = (u32) -1;
1156			num_bands++;
1157		}
1158	}
1159
1160	ie = kzalloc(num_bands * iebufsz, GFP_KERNEL);
 
 
 
1161	if (!ie) {
1162		ret = -ENOMEM;
1163		goto out;
1164	}
1165
1166	ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
1167
1168	ieee80211_build_preq_ies(local, ie, num_bands * iebufsz,
1169				 &sched_scan_ies, req->ie,
1170				 req->ie_len, bands_used, rate_masks, &chandef);
 
 
 
1171
1172	ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
1173	if (ret == 0) {
1174		rcu_assign_pointer(local->sched_scan_sdata, sdata);
1175		rcu_assign_pointer(local->sched_scan_req, req);
1176	}
1177
 
1178	kfree(ie);
1179
1180out:
1181	if (ret) {
1182		/* Clean in case of failure after HW restart or upon resume. */
1183		RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1184		RCU_INIT_POINTER(local->sched_scan_req, NULL);
1185	}
1186
1187	return ret;
1188}
1189
1190int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1191				       struct cfg80211_sched_scan_request *req)
1192{
1193	struct ieee80211_local *local = sdata->local;
1194	int ret;
1195
1196	mutex_lock(&local->mtx);
1197
1198	if (rcu_access_pointer(local->sched_scan_sdata)) {
1199		mutex_unlock(&local->mtx);
1200		return -EBUSY;
1201	}
1202
1203	ret = __ieee80211_request_sched_scan_start(sdata, req);
1204
1205	mutex_unlock(&local->mtx);
1206	return ret;
1207}
1208
1209int ieee80211_request_sched_scan_stop(struct ieee80211_local *local)
1210{
1211	struct ieee80211_sub_if_data *sched_scan_sdata;
1212	int ret = -ENOENT;
1213
1214	mutex_lock(&local->mtx);
1215
1216	if (!local->ops->sched_scan_stop) {
1217		ret = -ENOTSUPP;
1218		goto out;
1219	}
1220
1221	/* We don't want to restart sched scan anymore. */
1222	RCU_INIT_POINTER(local->sched_scan_req, NULL);
1223
1224	sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata,
1225						lockdep_is_held(&local->mtx));
1226	if (sched_scan_sdata) {
1227		ret = drv_sched_scan_stop(local, sched_scan_sdata);
1228		if (!ret)
1229			RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1230	}
1231out:
1232	mutex_unlock(&local->mtx);
1233
1234	return ret;
1235}
1236
1237void ieee80211_sched_scan_results(struct ieee80211_hw *hw)
1238{
1239	struct ieee80211_local *local = hw_to_local(hw);
1240
1241	trace_api_sched_scan_results(local);
1242
1243	cfg80211_sched_scan_results(hw->wiphy, 0);
1244}
1245EXPORT_SYMBOL(ieee80211_sched_scan_results);
1246
1247void ieee80211_sched_scan_end(struct ieee80211_local *local)
1248{
1249	mutex_lock(&local->mtx);
1250
1251	if (!rcu_access_pointer(local->sched_scan_sdata)) {
1252		mutex_unlock(&local->mtx);
1253		return;
1254	}
1255
1256	RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1257
1258	/* If sched scan was aborted by the driver. */
1259	RCU_INIT_POINTER(local->sched_scan_req, NULL);
1260
1261	mutex_unlock(&local->mtx);
1262
1263	cfg80211_sched_scan_stopped(local->hw.wiphy, 0);
1264}
1265
1266void ieee80211_sched_scan_stopped_work(struct work_struct *work)
 
1267{
1268	struct ieee80211_local *local =
1269		container_of(work, struct ieee80211_local,
1270			     sched_scan_stopped_work);
1271
1272	ieee80211_sched_scan_end(local);
1273}
1274
1275void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
1276{
1277	struct ieee80211_local *local = hw_to_local(hw);
1278
1279	trace_api_sched_scan_stopped(local);
1280
1281	/*
1282	 * this shouldn't really happen, so for simplicity
1283	 * simply ignore it, and let mac80211 reconfigure
1284	 * the sched scan later on.
1285	 */
1286	if (local->in_reconfig)
1287		return;
1288
1289	schedule_work(&local->sched_scan_stopped_work);
1290}
1291EXPORT_SYMBOL(ieee80211_sched_scan_stopped);