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v5.14.15
   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) 2018-2020 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
  58static void
  59ieee80211_update_bss_from_elems(struct ieee80211_local *local,
  60				struct ieee80211_bss *bss,
  61				struct ieee802_11_elems *elems,
  62				struct ieee80211_rx_status *rx_status,
  63				bool beacon)
  64{
 
 
 
 
 
 
 
 
  65	int clen, srlen;
  66
  67	if (beacon)
 
 
 
 
 
 
 
 
 
 
  68		bss->device_ts_beacon = rx_status->device_timestamp;
  69	else
  70		bss->device_ts_presp = rx_status->device_timestamp;
  71
  72	if (elems->parse_error) {
  73		if (beacon)
  74			bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON;
  75		else
  76			bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP;
  77	} else {
  78		if (beacon)
  79			bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON;
  80		else
  81			bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP;
  82	}
  83
  84	/* save the ERP value so that it is available at association time */
  85	if (elems->erp_info && (!elems->parse_error ||
  86				!(bss->valid_data & IEEE80211_BSS_VALID_ERP))) {
  87		bss->erp_value = elems->erp_info[0];
  88		bss->has_erp_value = true;
  89		if (!elems->parse_error)
  90			bss->valid_data |= IEEE80211_BSS_VALID_ERP;
  91	}
  92
  93	/* replace old supported rates if we get new values */
  94	if (!elems->parse_error ||
  95	    !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) {
  96		srlen = 0;
  97		if (elems->supp_rates) {
  98			clen = IEEE80211_MAX_SUPP_RATES;
  99			if (clen > elems->supp_rates_len)
 100				clen = elems->supp_rates_len;
 101			memcpy(bss->supp_rates, elems->supp_rates, clen);
 102			srlen += clen;
 103		}
 104		if (elems->ext_supp_rates) {
 105			clen = IEEE80211_MAX_SUPP_RATES - srlen;
 106			if (clen > elems->ext_supp_rates_len)
 107				clen = elems->ext_supp_rates_len;
 108			memcpy(bss->supp_rates + srlen, elems->ext_supp_rates,
 109			       clen);
 110			srlen += clen;
 111		}
 112		if (srlen) {
 113			bss->supp_rates_len = srlen;
 114			if (!elems->parse_error)
 115				bss->valid_data |= IEEE80211_BSS_VALID_RATES;
 116		}
 117	}
 118
 119	if (!elems->parse_error ||
 120	    !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) {
 121		bss->wmm_used = elems->wmm_param || elems->wmm_info;
 122		bss->uapsd_supported = is_uapsd_supported(elems);
 123		if (!elems->parse_error)
 124			bss->valid_data |= IEEE80211_BSS_VALID_WMM;
 125	}
 126
 127	if (beacon) {
 128		struct ieee80211_supported_band *sband =
 129			local->hw.wiphy->bands[rx_status->band];
 130		if (!(rx_status->encoding == RX_ENC_HT) &&
 131		    !(rx_status->encoding == RX_ENC_VHT))
 132			bss->beacon_rate =
 133				&sband->bitrates[rx_status->rate_idx];
 134	}
 135
 136	if (elems->vht_cap_elem)
 137		bss->vht_cap_info =
 138			le32_to_cpu(elems->vht_cap_elem->vht_cap_info);
 139	else
 140		bss->vht_cap_info = 0;
 
 
 141}
 142
 143struct ieee80211_bss *
 144ieee80211_bss_info_update(struct ieee80211_local *local,
 145			  struct ieee80211_rx_status *rx_status,
 146			  struct ieee80211_mgmt *mgmt, size_t len,
 147			  struct ieee80211_channel *channel)
 148{
 149	bool beacon = ieee80211_is_beacon(mgmt->frame_control) ||
 150		      ieee80211_is_s1g_beacon(mgmt->frame_control);
 151	struct cfg80211_bss *cbss, *non_tx_cbss;
 152	struct ieee80211_bss *bss, *non_tx_bss;
 
 
 
 153	struct cfg80211_inform_bss bss_meta = {
 154		.boottime_ns = rx_status->boottime_ns,
 
 155	};
 156	bool signal_valid;
 157	struct ieee80211_sub_if_data *scan_sdata;
 158	struct ieee802_11_elems elems;
 159	size_t baselen;
 160	u8 *elements;
 161
 162	if (rx_status->flag & RX_FLAG_NO_SIGNAL_VAL)
 163		bss_meta.signal = 0; /* invalid signal indication */
 164	else if (ieee80211_hw_check(&local->hw, SIGNAL_DBM))
 165		bss_meta.signal = rx_status->signal * 100;
 166	else if (ieee80211_hw_check(&local->hw, SIGNAL_UNSPEC))
 167		bss_meta.signal = (rx_status->signal * 100) / local->hw.max_signal;
 168
 169	bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_20;
 170	if (rx_status->bw == RATE_INFO_BW_5)
 171		bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_5;
 172	else if (rx_status->bw == RATE_INFO_BW_10)
 173		bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_10;
 174
 175	bss_meta.chan = channel;
 176
 177	rcu_read_lock();
 178	scan_sdata = rcu_dereference(local->scan_sdata);
 179	if (scan_sdata && scan_sdata->vif.type == NL80211_IFTYPE_STATION &&
 180	    scan_sdata->vif.bss_conf.assoc &&
 181	    ieee80211_have_rx_timestamp(rx_status)) {
 182		bss_meta.parent_tsf =
 183			ieee80211_calculate_rx_timestamp(local, rx_status,
 184							 len + FCS_LEN, 24);
 185		ether_addr_copy(bss_meta.parent_bssid,
 186				scan_sdata->vif.bss_conf.bssid);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 187	}
 188	rcu_read_unlock();
 189
 190	cbss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta,
 191					      mgmt, len, GFP_ATOMIC);
 192	if (!cbss)
 193		return NULL;
 194
 195	if (ieee80211_is_probe_resp(mgmt->frame_control)) {
 196		elements = mgmt->u.probe_resp.variable;
 197		baselen = offsetof(struct ieee80211_mgmt,
 198				   u.probe_resp.variable);
 199	} else if (ieee80211_is_s1g_beacon(mgmt->frame_control)) {
 200		struct ieee80211_ext *ext = (void *) mgmt;
 201
 202		baselen = offsetof(struct ieee80211_ext, u.s1g_beacon.variable);
 203		elements = ext->u.s1g_beacon.variable;
 204	} else {
 205		baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable);
 206		elements = mgmt->u.beacon.variable;
 207	}
 208
 209	if (baselen > len)
 210		return NULL;
 211
 212	ieee802_11_parse_elems(elements, len - baselen, false, &elems,
 213			       mgmt->bssid, cbss->bssid);
 214
 215	/* In case the signal is invalid update the status */
 216	signal_valid = channel == cbss->channel;
 217	if (!signal_valid)
 218		rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL;
 219
 220	bss = (void *)cbss->priv;
 221	ieee80211_update_bss_from_elems(local, bss, &elems, rx_status, beacon);
 222
 223	list_for_each_entry(non_tx_cbss, &cbss->nontrans_list, nontrans_list) {
 224		non_tx_bss = (void *)non_tx_cbss->priv;
 225
 226		ieee80211_update_bss_from_elems(local, non_tx_bss, &elems,
 227						rx_status, beacon);
 228	}
 229
 230	return bss;
 231}
 232
 233static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata,
 
 234					u32 scan_flags, const u8 *da)
 235{
 236	if (!sdata)
 237		return false;
 238	/* accept broadcast for OCE */
 239	if (scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP &&
 240	    is_broadcast_ether_addr(da))
 
 
 241		return true;
 
 242	if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
 243		return true;
 244	return ether_addr_equal(da, sdata->vif.addr);
 245}
 246
 247void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb)
 248{
 249	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
 250	struct ieee80211_sub_if_data *sdata1, *sdata2;
 251	struct ieee80211_mgmt *mgmt = (void *)skb->data;
 252	struct ieee80211_bss *bss;
 253	struct ieee80211_channel *channel;
 254	size_t min_hdr_len = offsetof(struct ieee80211_mgmt,
 255				      u.probe_resp.variable);
 256
 257	if (!ieee80211_is_probe_resp(mgmt->frame_control) &&
 258	    !ieee80211_is_beacon(mgmt->frame_control) &&
 259	    !ieee80211_is_s1g_beacon(mgmt->frame_control))
 260		return;
 261
 262	if (ieee80211_is_s1g_beacon(mgmt->frame_control)) {
 263		if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
 264			min_hdr_len = offsetof(struct ieee80211_ext,
 265					       u.s1g_short_beacon.variable);
 266		else
 267			min_hdr_len = offsetof(struct ieee80211_ext,
 268					       u.s1g_beacon);
 269	}
 270
 271	if (skb->len < min_hdr_len)
 272		return;
 273
 274	sdata1 = rcu_dereference(local->scan_sdata);
 275	sdata2 = rcu_dereference(local->sched_scan_sdata);
 
 
 
 
 
 
 
 
 
 
 276
 277	if (likely(!sdata1 && !sdata2))
 278		return;
 279
 280	if (ieee80211_is_probe_resp(mgmt->frame_control)) {
 
 281		struct cfg80211_scan_request *scan_req;
 282		struct cfg80211_sched_scan_request *sched_scan_req;
 283		u32 scan_req_flags = 0, sched_scan_req_flags = 0;
 284
 
 
 
 
 
 
 285		scan_req = rcu_dereference(local->scan_req);
 286		sched_scan_req = rcu_dereference(local->sched_scan_req);
 287
 288		if (scan_req)
 289			scan_req_flags = scan_req->flags;
 290
 291		if (sched_scan_req)
 292			sched_scan_req_flags = sched_scan_req->flags;
 293
 294		/* ignore ProbeResp to foreign address or non-bcast (OCE)
 295		 * unless scanning with randomised address
 296		 */
 297		if (!ieee80211_scan_accept_presp(sdata1, scan_req_flags,
 
 298						 mgmt->da) &&
 299		    !ieee80211_scan_accept_presp(sdata2, sched_scan_req_flags,
 
 300						 mgmt->da))
 301			return;
 
 
 
 
 302	}
 303
 304	channel = ieee80211_get_channel_khz(local->hw.wiphy,
 305					ieee80211_rx_status_to_khz(rx_status));
 306
 307	if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 308		return;
 309
 310	bss = ieee80211_bss_info_update(local, rx_status,
 311					mgmt, skb->len,
 312					channel);
 313	if (bss)
 314		ieee80211_rx_bss_put(local, bss);
 315}
 316
 317static void
 318ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef,
 319			       enum nl80211_bss_scan_width scan_width)
 320{
 321	memset(chandef, 0, sizeof(*chandef));
 322	switch (scan_width) {
 323	case NL80211_BSS_CHAN_WIDTH_5:
 324		chandef->width = NL80211_CHAN_WIDTH_5;
 325		break;
 326	case NL80211_BSS_CHAN_WIDTH_10:
 327		chandef->width = NL80211_CHAN_WIDTH_10;
 328		break;
 329	default:
 330		chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
 331		break;
 332	}
 333}
 334
 335/* return false if no more work */
 336static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data *sdata)
 337{
 338	struct ieee80211_local *local = sdata->local;
 339	struct cfg80211_scan_request *req;
 340	struct cfg80211_chan_def chandef;
 341	u8 bands_used = 0;
 342	int i, ielen, n_chans;
 
 343	u32 flags = 0;
 344
 345	req = rcu_dereference_protected(local->scan_req,
 346					lockdep_is_held(&local->mtx));
 347
 348	if (test_bit(SCAN_HW_CANCELLED, &local->scanning))
 349		return false;
 350
 351	if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
 
 
 352		for (i = 0; i < req->n_channels; i++) {
 353			local->hw_scan_req->req.channels[i] = req->channels[i];
 354			bands_used |= BIT(req->channels[i]->band);
 355		}
 356
 357		n_chans = req->n_channels;
 358	} else {
 359		do {
 360			if (local->hw_scan_band == NUM_NL80211_BANDS)
 361				return false;
 362
 363			n_chans = 0;
 
 364
 365			for (i = 0; i < req->n_channels; i++) {
 366				if (req->channels[i]->band !=
 367				    local->hw_scan_band)
 368					continue;
 369				local->hw_scan_req->req.channels[n_chans] =
 370							req->channels[i];
 371				n_chans++;
 372				bands_used |= BIT(req->channels[i]->band);
 373			}
 374
 375			local->hw_scan_band++;
 376		} while (!n_chans);
 377	}
 378
 379	local->hw_scan_req->req.n_channels = n_chans;
 380	ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
 381
 382	if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
 383		flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
 384
 385	ielen = ieee80211_build_preq_ies(sdata,
 386					 (u8 *)local->hw_scan_req->req.ie,
 387					 local->hw_scan_ies_bufsize,
 388					 &local->hw_scan_req->ies,
 389					 req->ie, req->ie_len,
 390					 bands_used, req->rates, &chandef,
 391					 flags);
 
 
 392	local->hw_scan_req->req.ie_len = ielen;
 393	local->hw_scan_req->req.no_cck = req->no_cck;
 394	ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr);
 395	ether_addr_copy(local->hw_scan_req->req.mac_addr_mask,
 396			req->mac_addr_mask);
 397	ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid);
 398
 399	return true;
 400}
 401
 402static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
 403{
 404	struct ieee80211_local *local = hw_to_local(hw);
 405	bool hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning);
 406	bool was_scanning = local->scanning;
 407	struct cfg80211_scan_request *scan_req;
 408	struct ieee80211_sub_if_data *scan_sdata;
 409	struct ieee80211_sub_if_data *sdata;
 410
 411	lockdep_assert_held(&local->mtx);
 412
 413	/*
 414	 * It's ok to abort a not-yet-running scan (that
 415	 * we have one at all will be verified by checking
 416	 * local->scan_req next), but not to complete it
 417	 * successfully.
 418	 */
 419	if (WARN_ON(!local->scanning && !aborted))
 420		aborted = true;
 421
 422	if (WARN_ON(!local->scan_req))
 423		return;
 424
 425	scan_sdata = rcu_dereference_protected(local->scan_sdata,
 426					       lockdep_is_held(&local->mtx));
 427
 428	if (hw_scan && !aborted &&
 429	    !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) &&
 430	    ieee80211_prep_hw_scan(scan_sdata)) {
 431		int rc;
 432
 433		rc = drv_hw_scan(local,
 434			rcu_dereference_protected(local->scan_sdata,
 435						  lockdep_is_held(&local->mtx)),
 436			local->hw_scan_req);
 437
 438		if (rc == 0)
 439			return;
 440
 441		/* HW scan failed and is going to be reported as aborted,
 442		 * so clear old scan info.
 443		 */
 444		memset(&local->scan_info, 0, sizeof(local->scan_info));
 445		aborted = true;
 446	}
 447
 448	kfree(local->hw_scan_req);
 449	local->hw_scan_req = NULL;
 450
 451	scan_req = rcu_dereference_protected(local->scan_req,
 452					     lockdep_is_held(&local->mtx));
 453
 454	if (scan_req != local->int_scan_req) {
 455		local->scan_info.aborted = aborted;
 456		cfg80211_scan_done(scan_req, &local->scan_info);
 457	}
 458	RCU_INIT_POINTER(local->scan_req, NULL);
 459	RCU_INIT_POINTER(local->scan_sdata, NULL);
 460
 461	local->scanning = 0;
 462	local->scan_chandef.chan = NULL;
 463
 
 
 
 
 
 
 
 464	/* Set power back to normal operating levels. */
 465	ieee80211_hw_config(local, 0);
 466
 467	if (!hw_scan) {
 468		ieee80211_configure_filter(local);
 469		drv_sw_scan_complete(local, scan_sdata);
 470		ieee80211_offchannel_return(local);
 471	}
 472
 473	ieee80211_recalc_idle(local);
 474
 475	ieee80211_mlme_notify_scan_completed(local);
 476	ieee80211_ibss_notify_scan_completed(local);
 477
 478	/* Requeue all the work that might have been ignored while
 479	 * the scan was in progress; if there was none this will
 480	 * just be a no-op for the particular interface.
 481	 */
 482	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 483		if (ieee80211_sdata_running(sdata))
 484			ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 485	}
 486
 487	if (was_scanning)
 488		ieee80211_start_next_roc(local);
 489}
 490
 491void ieee80211_scan_completed(struct ieee80211_hw *hw,
 492			      struct cfg80211_scan_info *info)
 493{
 494	struct ieee80211_local *local = hw_to_local(hw);
 495
 496	trace_api_scan_completed(local, info->aborted);
 497
 498	set_bit(SCAN_COMPLETED, &local->scanning);
 499	if (info->aborted)
 500		set_bit(SCAN_ABORTED, &local->scanning);
 501
 502	memcpy(&local->scan_info, info, sizeof(*info));
 503
 504	ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
 505}
 506EXPORT_SYMBOL(ieee80211_scan_completed);
 507
 508static int ieee80211_start_sw_scan(struct ieee80211_local *local,
 509				   struct ieee80211_sub_if_data *sdata)
 510{
 511	/* Software scan is not supported in multi-channel cases */
 512	if (local->use_chanctx)
 513		return -EOPNOTSUPP;
 514
 515	/*
 516	 * Hardware/driver doesn't support hw_scan, so use software
 517	 * scanning instead. First send a nullfunc frame with power save
 518	 * bit on so that AP will buffer the frames for us while we are not
 519	 * listening, then send probe requests to each channel and wait for
 520	 * the responses. After all channels are scanned, tune back to the
 521	 * original channel and send a nullfunc frame with power save bit
 522	 * off to trigger the AP to send us all the buffered frames.
 523	 *
 524	 * Note that while local->sw_scanning is true everything else but
 525	 * nullfunc frames and probe requests will be dropped in
 526	 * ieee80211_tx_h_check_assoc().
 527	 */
 528	drv_sw_scan_start(local, sdata, local->scan_addr);
 529
 530	local->leave_oper_channel_time = jiffies;
 531	local->next_scan_state = SCAN_DECISION;
 532	local->scan_channel_idx = 0;
 533
 534	ieee80211_offchannel_stop_vifs(local);
 535
 536	/* ensure nullfunc is transmitted before leaving operating channel */
 537	ieee80211_flush_queues(local, NULL, false);
 538
 539	ieee80211_configure_filter(local);
 540
 541	/* We need to set power level at maximum rate for scanning. */
 542	ieee80211_hw_config(local, 0);
 543
 544	ieee80211_queue_delayed_work(&local->hw,
 545				     &local->scan_work, 0);
 546
 547	return 0;
 548}
 549
 550static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata)
 551{
 552	struct ieee80211_local *local = sdata->local;
 553	struct ieee80211_sub_if_data *sdata_iter;
 
 
 
 554
 555	if (!ieee80211_is_radar_required(local))
 556		return true;
 557
 558	if (!regulatory_pre_cac_allowed(local->hw.wiphy))
 559		return false;
 560
 561	mutex_lock(&local->iflist_mtx);
 562	list_for_each_entry(sdata_iter, &local->interfaces, list) {
 563		if (sdata_iter->wdev.cac_started) {
 564			mutex_unlock(&local->iflist_mtx);
 565			return false;
 566		}
 567	}
 568	mutex_unlock(&local->iflist_mtx);
 569
 570	return true;
 571}
 572
 573static bool ieee80211_can_scan(struct ieee80211_local *local,
 574			       struct ieee80211_sub_if_data *sdata)
 575{
 576	if (!__ieee80211_can_leave_ch(sdata))
 577		return false;
 578
 579	if (!list_empty(&local->roc_list))
 580		return false;
 581
 582	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
 583	    sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL)
 584		return false;
 585
 586	return true;
 587}
 588
 589void ieee80211_run_deferred_scan(struct ieee80211_local *local)
 590{
 591	lockdep_assert_held(&local->mtx);
 592
 593	if (!local->scan_req || local->scanning)
 594		return;
 595
 596	if (!ieee80211_can_scan(local,
 597				rcu_dereference_protected(
 598					local->scan_sdata,
 599					lockdep_is_held(&local->mtx))))
 600		return;
 601
 602	ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
 603				     round_jiffies_relative(0));
 604}
 605
 606static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata,
 607					  const u8 *src, const u8 *dst,
 608					  const u8 *ssid, size_t ssid_len,
 609					  const u8 *ie, size_t ie_len,
 610					  u32 ratemask, u32 flags, u32 tx_flags,
 611					  struct ieee80211_channel *channel)
 612{
 613	struct sk_buff *skb;
 614
 615	skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel,
 616					ssid, ssid_len,
 617					ie, ie_len, flags);
 618
 619	if (skb) {
 620		if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) {
 621			struct ieee80211_hdr *hdr = (void *)skb->data;
 622			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 623			u16 sn = get_random_u32();
 624
 625			info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO;
 626			hdr->seq_ctrl =
 627				cpu_to_le16(IEEE80211_SN_TO_SEQ(sn));
 628		}
 629		IEEE80211_SKB_CB(skb)->flags |= tx_flags;
 
 630		ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band);
 631	}
 632}
 633
 634static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
 635					    unsigned long *next_delay)
 636{
 637	int i;
 638	struct ieee80211_sub_if_data *sdata;
 639	struct cfg80211_scan_request *scan_req;
 640	enum nl80211_band band = local->hw.conf.chandef.chan->band;
 641	u32 flags = 0, tx_flags;
 642
 643	scan_req = rcu_dereference_protected(local->scan_req,
 644					     lockdep_is_held(&local->mtx));
 645
 646	tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
 647	if (scan_req->no_cck)
 648		tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
 649	if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
 650		flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
 651	if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN)
 652		flags |= IEEE80211_PROBE_FLAG_RANDOM_SN;
 653
 654	sdata = rcu_dereference_protected(local->scan_sdata,
 655					  lockdep_is_held(&local->mtx));
 656
 657	for (i = 0; i < scan_req->n_ssids; i++)
 658		ieee80211_send_scan_probe_req(
 659			sdata, local->scan_addr, scan_req->bssid,
 660			scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len,
 661			scan_req->ie, scan_req->ie_len,
 662			scan_req->rates[band], flags,
 663			tx_flags, local->hw.conf.chandef.chan);
 664
 665	/*
 666	 * After sending probe requests, wait for probe responses
 667	 * on the channel.
 668	 */
 669	*next_delay = IEEE80211_CHANNEL_TIME;
 
 
 
 670	local->next_scan_state = SCAN_DECISION;
 671}
 672
 673static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
 674				  struct cfg80211_scan_request *req)
 675{
 676	struct ieee80211_local *local = sdata->local;
 677	bool hw_scan = local->ops->hw_scan;
 678	int rc;
 679
 680	lockdep_assert_held(&local->mtx);
 681
 682	if (local->scan_req)
 683		return -EBUSY;
 684
 
 
 
 
 
 
 
 685	if (!__ieee80211_can_leave_ch(sdata))
 686		return -EBUSY;
 687
 688	if (!ieee80211_can_scan(local, sdata)) {
 689		/* wait for the work to finish/time out */
 690		rcu_assign_pointer(local->scan_req, req);
 691		rcu_assign_pointer(local->scan_sdata, sdata);
 692		return 0;
 693	}
 694
 695 again:
 696	if (hw_scan) {
 697		u8 *ies;
 698
 699		local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len;
 700
 701		if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
 702			int i, n_bands = 0;
 703			u8 bands_counted = 0;
 704
 705			for (i = 0; i < req->n_channels; i++) {
 706				if (bands_counted & BIT(req->channels[i]->band))
 707					continue;
 708				bands_counted |= BIT(req->channels[i]->band);
 709				n_bands++;
 710			}
 711
 712			local->hw_scan_ies_bufsize *= n_bands;
 713		}
 714
 715		local->hw_scan_req = kmalloc(
 716				sizeof(*local->hw_scan_req) +
 717				req->n_channels * sizeof(req->channels[0]) +
 718				local->hw_scan_ies_bufsize, GFP_KERNEL);
 
 719		if (!local->hw_scan_req)
 720			return -ENOMEM;
 721
 722		local->hw_scan_req->req.ssids = req->ssids;
 723		local->hw_scan_req->req.n_ssids = req->n_ssids;
 
 
 
 
 
 724		ies = (u8 *)local->hw_scan_req +
 725			sizeof(*local->hw_scan_req) +
 726			req->n_channels * sizeof(req->channels[0]);
 727		local->hw_scan_req->req.ie = ies;
 728		local->hw_scan_req->req.flags = req->flags;
 729		eth_broadcast_addr(local->hw_scan_req->req.bssid);
 730		local->hw_scan_req->req.duration = req->duration;
 731		local->hw_scan_req->req.duration_mandatory =
 732			req->duration_mandatory;
 
 
 733
 734		local->hw_scan_band = 0;
 735		local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params;
 736		local->hw_scan_req->req.scan_6ghz_params =
 737			req->scan_6ghz_params;
 738		local->hw_scan_req->req.scan_6ghz = req->scan_6ghz;
 739
 740		/*
 741		 * After allocating local->hw_scan_req, we must
 742		 * go through until ieee80211_prep_hw_scan(), so
 743		 * anything that might be changed here and leave
 744		 * this function early must not go after this
 745		 * allocation.
 746		 */
 747	}
 748
 749	rcu_assign_pointer(local->scan_req, req);
 750	rcu_assign_pointer(local->scan_sdata, sdata);
 751
 752	if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
 753		get_random_mask_addr(local->scan_addr,
 754				     req->mac_addr,
 755				     req->mac_addr_mask);
 756	else
 757		memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN);
 758
 759	if (hw_scan) {
 760		__set_bit(SCAN_HW_SCANNING, &local->scanning);
 761	} else if ((req->n_channels == 1) &&
 762		   (req->channels[0] == local->_oper_chandef.chan)) {
 763		/*
 764		 * If we are scanning only on the operating channel
 765		 * then we do not need to stop normal activities
 766		 */
 767		unsigned long next_delay;
 768
 769		__set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
 770
 771		ieee80211_recalc_idle(local);
 772
 773		/* Notify driver scan is starting, keep order of operations
 774		 * same as normal software scan, in case that matters. */
 775		drv_sw_scan_start(local, sdata, local->scan_addr);
 776
 777		ieee80211_configure_filter(local); /* accept probe-responses */
 778
 779		/* We need to ensure power level is at max for scanning. */
 780		ieee80211_hw_config(local, 0);
 781
 782		if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR |
 783						IEEE80211_CHAN_RADAR)) ||
 784		    !req->n_ssids) {
 785			next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
 
 
 786		} else {
 787			ieee80211_scan_state_send_probe(local, &next_delay);
 788			next_delay = IEEE80211_CHANNEL_TIME;
 789		}
 790
 791		/* Now, just wait a bit and we are all done! */
 792		ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
 793					     next_delay);
 794		return 0;
 795	} else {
 796		/* Do normal software scan */
 797		__set_bit(SCAN_SW_SCANNING, &local->scanning);
 798	}
 799
 800	ieee80211_recalc_idle(local);
 801
 802	if (hw_scan) {
 803		WARN_ON(!ieee80211_prep_hw_scan(sdata));
 804		rc = drv_hw_scan(local, sdata, local->hw_scan_req);
 805	} else {
 806		rc = ieee80211_start_sw_scan(local, sdata);
 807	}
 808
 809	if (rc) {
 810		kfree(local->hw_scan_req);
 811		local->hw_scan_req = NULL;
 812		local->scanning = 0;
 813
 814		ieee80211_recalc_idle(local);
 815
 816		local->scan_req = NULL;
 817		RCU_INIT_POINTER(local->scan_sdata, NULL);
 818	}
 819
 820	if (hw_scan && rc == 1) {
 821		/*
 822		 * we can't fall back to software for P2P-GO
 823		 * as it must update NoA etc.
 824		 */
 825		if (ieee80211_vif_type_p2p(&sdata->vif) ==
 826				NL80211_IFTYPE_P2P_GO)
 827			return -EOPNOTSUPP;
 828		hw_scan = false;
 829		goto again;
 830	}
 831
 832	return rc;
 833}
 834
 835static unsigned long
 836ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
 837{
 838	/*
 839	 * TODO: channel switching also consumes quite some time,
 840	 * add that delay as well to get a better estimation
 841	 */
 842	if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR))
 843		return IEEE80211_PASSIVE_CHANNEL_TIME;
 844	return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
 845}
 846
 847static void ieee80211_scan_state_decision(struct ieee80211_local *local,
 848					  unsigned long *next_delay)
 849{
 850	bool associated = false;
 851	bool tx_empty = true;
 852	bool bad_latency;
 853	struct ieee80211_sub_if_data *sdata;
 854	struct ieee80211_channel *next_chan;
 855	enum mac80211_scan_state next_scan_state;
 856	struct cfg80211_scan_request *scan_req;
 857
 
 
 858	/*
 859	 * check if at least one STA interface is associated,
 860	 * check if at least one STA interface has pending tx frames
 861	 * and grab the lowest used beacon interval
 862	 */
 863	mutex_lock(&local->iflist_mtx);
 864	list_for_each_entry(sdata, &local->interfaces, list) {
 865		if (!ieee80211_sdata_running(sdata))
 866			continue;
 867
 868		if (sdata->vif.type == NL80211_IFTYPE_STATION) {
 869			if (sdata->u.mgd.associated) {
 870				associated = true;
 871
 872				if (!qdisc_all_tx_empty(sdata->dev)) {
 873					tx_empty = false;
 874					break;
 875				}
 876			}
 877		}
 878	}
 879	mutex_unlock(&local->iflist_mtx);
 880
 881	scan_req = rcu_dereference_protected(local->scan_req,
 882					     lockdep_is_held(&local->mtx));
 883
 884	next_chan = scan_req->channels[local->scan_channel_idx];
 885
 886	/*
 887	 * we're currently scanning a different channel, let's
 888	 * see if we can scan another channel without interfering
 889	 * with the current traffic situation.
 890	 *
 891	 * Keep good latency, do not stay off-channel more than 125 ms.
 892	 */
 893
 894	bad_latency = time_after(jiffies +
 895				 ieee80211_scan_get_channel_time(next_chan),
 896				 local->leave_oper_channel_time + HZ / 8);
 897
 898	if (associated && !tx_empty) {
 899		if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY)
 900			next_scan_state = SCAN_ABORT;
 901		else
 902			next_scan_state = SCAN_SUSPEND;
 903	} else if (associated && bad_latency) {
 904		next_scan_state = SCAN_SUSPEND;
 905	} else {
 906		next_scan_state = SCAN_SET_CHANNEL;
 907	}
 908
 909	local->next_scan_state = next_scan_state;
 910
 911	*next_delay = 0;
 912}
 913
 914static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
 915					     unsigned long *next_delay)
 916{
 917	int skip;
 918	struct ieee80211_channel *chan;
 919	enum nl80211_bss_scan_width oper_scan_width;
 920	struct cfg80211_scan_request *scan_req;
 921
 922	scan_req = rcu_dereference_protected(local->scan_req,
 923					     lockdep_is_held(&local->mtx));
 924
 925	skip = 0;
 926	chan = scan_req->channels[local->scan_channel_idx];
 927
 928	local->scan_chandef.chan = chan;
 929	local->scan_chandef.center_freq1 = chan->center_freq;
 930	local->scan_chandef.freq1_offset = chan->freq_offset;
 931	local->scan_chandef.center_freq2 = 0;
 932
 933	/* For scanning on the S1G band, ignore scan_width (which is constant
 934	 * across all channels) for now since channel width is specific to each
 935	 * channel. Detect the required channel width here and likely revisit
 936	 * later. Maybe scan_width could be used to build the channel scan list?
 937	 */
 938	if (chan->band == NL80211_BAND_S1GHZ) {
 939		local->scan_chandef.width = ieee80211_s1g_channel_width(chan);
 940		goto set_channel;
 941	}
 942
 943	switch (scan_req->scan_width) {
 944	case NL80211_BSS_CHAN_WIDTH_5:
 945		local->scan_chandef.width = NL80211_CHAN_WIDTH_5;
 946		break;
 947	case NL80211_BSS_CHAN_WIDTH_10:
 948		local->scan_chandef.width = NL80211_CHAN_WIDTH_10;
 949		break;
 950	default:
 951	case NL80211_BSS_CHAN_WIDTH_20:
 952		/* If scanning on oper channel, use whatever channel-type
 953		 * is currently in use.
 954		 */
 955		oper_scan_width = cfg80211_chandef_to_scan_width(
 956					&local->_oper_chandef);
 957		if (chan == local->_oper_chandef.chan &&
 958		    oper_scan_width == scan_req->scan_width)
 959			local->scan_chandef = local->_oper_chandef;
 960		else
 961			local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
 962		break;
 963	case NL80211_BSS_CHAN_WIDTH_1:
 964	case NL80211_BSS_CHAN_WIDTH_2:
 965		/* shouldn't get here, S1G handled above */
 966		WARN_ON(1);
 967		break;
 968	}
 969
 970set_channel:
 971	if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL))
 972		skip = 1;
 973
 974	/* advance state machine to next channel/band */
 975	local->scan_channel_idx++;
 976
 977	if (skip) {
 978		/* if we skip this channel return to the decision state */
 979		local->next_scan_state = SCAN_DECISION;
 980		return;
 981	}
 982
 983	/*
 984	 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
 985	 * (which unfortunately doesn't say _why_ step a) is done,
 986	 * but it waits for the probe delay or until a frame is
 987	 * received - and the received frame would update the NAV).
 988	 * For now, we do not support waiting until a frame is
 989	 * received.
 990	 *
 991	 * In any case, it is not necessary for a passive scan.
 992	 */
 993	if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) ||
 994	    !scan_req->n_ssids) {
 995		*next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
 
 996		local->next_scan_state = SCAN_DECISION;
 
 
 997		return;
 998	}
 999
1000	/* active scan, send probes */
1001	*next_delay = IEEE80211_PROBE_DELAY;
1002	local->next_scan_state = SCAN_SEND_PROBE;
1003}
1004
1005static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
1006					 unsigned long *next_delay)
1007{
1008	/* switch back to the operating channel */
1009	local->scan_chandef.chan = NULL;
1010	ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
1011
1012	/* disable PS */
1013	ieee80211_offchannel_return(local);
1014
1015	*next_delay = HZ / 5;
1016	/* afterwards, resume scan & go to next channel */
1017	local->next_scan_state = SCAN_RESUME;
1018}
1019
1020static void ieee80211_scan_state_resume(struct ieee80211_local *local,
1021					unsigned long *next_delay)
1022{
1023	ieee80211_offchannel_stop_vifs(local);
1024
1025	if (local->ops->flush) {
1026		ieee80211_flush_queues(local, NULL, false);
1027		*next_delay = 0;
1028	} else
1029		*next_delay = HZ / 10;
1030
1031	/* remember when we left the operating channel */
1032	local->leave_oper_channel_time = jiffies;
1033
1034	/* advance to the next channel to be scanned */
1035	local->next_scan_state = SCAN_SET_CHANNEL;
1036}
1037
1038void ieee80211_scan_work(struct work_struct *work)
1039{
1040	struct ieee80211_local *local =
1041		container_of(work, struct ieee80211_local, scan_work.work);
1042	struct ieee80211_sub_if_data *sdata;
1043	struct cfg80211_scan_request *scan_req;
1044	unsigned long next_delay = 0;
1045	bool aborted;
1046
1047	mutex_lock(&local->mtx);
1048
1049	if (!ieee80211_can_run_worker(local)) {
1050		aborted = true;
1051		goto out_complete;
1052	}
1053
1054	sdata = rcu_dereference_protected(local->scan_sdata,
1055					  lockdep_is_held(&local->mtx));
1056	scan_req = rcu_dereference_protected(local->scan_req,
1057					     lockdep_is_held(&local->mtx));
1058
1059	/* When scanning on-channel, the first-callback means completed. */
1060	if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) {
1061		aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
1062		goto out_complete;
1063	}
1064
1065	if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) {
1066		aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
1067		goto out_complete;
1068	}
1069
1070	if (!sdata || !scan_req)
1071		goto out;
1072
1073	if (!local->scanning) {
1074		int rc;
1075
1076		RCU_INIT_POINTER(local->scan_req, NULL);
1077		RCU_INIT_POINTER(local->scan_sdata, NULL);
1078
1079		rc = __ieee80211_start_scan(sdata, scan_req);
1080		if (rc) {
1081			/* need to complete scan in cfg80211 */
1082			rcu_assign_pointer(local->scan_req, scan_req);
1083			aborted = true;
1084			goto out_complete;
1085		} else
1086			goto out;
1087	}
1088
 
 
1089	/*
1090	 * as long as no delay is required advance immediately
1091	 * without scheduling a new work
1092	 */
1093	do {
1094		if (!ieee80211_sdata_running(sdata)) {
1095			aborted = true;
1096			goto out_complete;
1097		}
1098
 
 
 
 
1099		switch (local->next_scan_state) {
1100		case SCAN_DECISION:
1101			/* if no more bands/channels left, complete scan */
1102			if (local->scan_channel_idx >= scan_req->n_channels) {
1103				aborted = false;
1104				goto out_complete;
1105			}
1106			ieee80211_scan_state_decision(local, &next_delay);
1107			break;
1108		case SCAN_SET_CHANNEL:
1109			ieee80211_scan_state_set_channel(local, &next_delay);
1110			break;
1111		case SCAN_SEND_PROBE:
1112			ieee80211_scan_state_send_probe(local, &next_delay);
1113			break;
1114		case SCAN_SUSPEND:
1115			ieee80211_scan_state_suspend(local, &next_delay);
1116			break;
1117		case SCAN_RESUME:
1118			ieee80211_scan_state_resume(local, &next_delay);
1119			break;
1120		case SCAN_ABORT:
1121			aborted = true;
1122			goto out_complete;
1123		}
1124	} while (next_delay == 0);
1125
1126	ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay);
1127	goto out;
 
1128
1129out_complete:
1130	__ieee80211_scan_completed(&local->hw, aborted);
1131out:
1132	mutex_unlock(&local->mtx);
1133}
1134
1135int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
1136			   struct cfg80211_scan_request *req)
1137{
1138	int res;
1139
1140	mutex_lock(&sdata->local->mtx);
1141	res = __ieee80211_start_scan(sdata, req);
1142	mutex_unlock(&sdata->local->mtx);
1143
1144	return res;
1145}
1146
1147int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
1148				const u8 *ssid, u8 ssid_len,
1149				struct ieee80211_channel **channels,
1150				unsigned int n_channels,
1151				enum nl80211_bss_scan_width scan_width)
1152{
1153	struct ieee80211_local *local = sdata->local;
1154	int ret = -EBUSY, i, n_ch = 0;
1155	enum nl80211_band band;
1156
1157	mutex_lock(&local->mtx);
1158
1159	/* busy scanning */
1160	if (local->scan_req)
1161		goto unlock;
1162
1163	/* fill internal scan request */
1164	if (!channels) {
1165		int max_n;
1166
1167		for (band = 0; band < NUM_NL80211_BANDS; band++) {
1168			if (!local->hw.wiphy->bands[band] ||
1169			    band == NL80211_BAND_6GHZ)
1170				continue;
1171
1172			max_n = local->hw.wiphy->bands[band]->n_channels;
1173			for (i = 0; i < max_n; i++) {
1174				struct ieee80211_channel *tmp_ch =
1175				    &local->hw.wiphy->bands[band]->channels[i];
1176
1177				if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR |
1178						     IEEE80211_CHAN_DISABLED))
 
 
1179					continue;
1180
1181				local->int_scan_req->channels[n_ch] = tmp_ch;
1182				n_ch++;
1183			}
1184		}
1185
1186		if (WARN_ON_ONCE(n_ch == 0))
1187			goto unlock;
1188
1189		local->int_scan_req->n_channels = n_ch;
1190	} else {
1191		for (i = 0; i < n_channels; i++) {
1192			if (channels[i]->flags & (IEEE80211_CHAN_NO_IR |
1193						  IEEE80211_CHAN_DISABLED))
 
 
1194				continue;
1195
1196			local->int_scan_req->channels[n_ch] = channels[i];
1197			n_ch++;
1198		}
1199
1200		if (WARN_ON_ONCE(n_ch == 0))
1201			goto unlock;
1202
1203		local->int_scan_req->n_channels = n_ch;
1204	}
1205
1206	local->int_scan_req->ssids = &local->scan_ssid;
1207	local->int_scan_req->n_ssids = 1;
1208	local->int_scan_req->scan_width = scan_width;
1209	memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
1210	local->int_scan_req->ssids[0].ssid_len = ssid_len;
1211
1212	ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
1213 unlock:
1214	mutex_unlock(&local->mtx);
1215	return ret;
1216}
1217
1218/*
1219 * Only call this function when a scan can't be queued -- under RTNL.
1220 */
1221void ieee80211_scan_cancel(struct ieee80211_local *local)
1222{
 
 
 
1223	/*
1224	 * We are canceling software scan, or deferred scan that was not
1225	 * yet really started (see __ieee80211_start_scan ).
1226	 *
1227	 * Regarding hardware scan:
1228	 * - we can not call  __ieee80211_scan_completed() as when
1229	 *   SCAN_HW_SCANNING bit is set this function change
1230	 *   local->hw_scan_req to operate on 5G band, what race with
1231	 *   driver which can use local->hw_scan_req
1232	 *
1233	 * - we can not cancel scan_work since driver can schedule it
1234	 *   by ieee80211_scan_completed(..., true) to finish scan
1235	 *
1236	 * Hence we only call the cancel_hw_scan() callback, but the low-level
1237	 * driver is still responsible for calling ieee80211_scan_completed()
1238	 * after the scan was completed/aborted.
1239	 */
1240
1241	mutex_lock(&local->mtx);
1242	if (!local->scan_req)
1243		goto out;
1244
1245	/*
1246	 * We have a scan running and the driver already reported completion,
1247	 * but the worker hasn't run yet or is stuck on the mutex - mark it as
1248	 * cancelled.
1249	 */
1250	if (test_bit(SCAN_HW_SCANNING, &local->scanning) &&
1251	    test_bit(SCAN_COMPLETED, &local->scanning)) {
1252		set_bit(SCAN_HW_CANCELLED, &local->scanning);
1253		goto out;
1254	}
1255
1256	if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
1257		/*
1258		 * Make sure that __ieee80211_scan_completed doesn't trigger a
1259		 * scan on another band.
1260		 */
1261		set_bit(SCAN_HW_CANCELLED, &local->scanning);
1262		if (local->ops->cancel_hw_scan)
1263			drv_cancel_hw_scan(local,
1264				rcu_dereference_protected(local->scan_sdata,
1265						lockdep_is_held(&local->mtx)));
1266		goto out;
1267	}
1268
1269	/*
1270	 * If the work is currently running, it must be blocked on
1271	 * the mutex, but we'll set scan_sdata = NULL and it'll
1272	 * simply exit once it acquires the mutex.
1273	 */
1274	cancel_delayed_work(&local->scan_work);
1275	/* and clean up */
1276	memset(&local->scan_info, 0, sizeof(local->scan_info));
1277	__ieee80211_scan_completed(&local->hw, true);
1278out:
1279	mutex_unlock(&local->mtx);
1280}
1281
1282int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1283					struct cfg80211_sched_scan_request *req)
1284{
1285	struct ieee80211_local *local = sdata->local;
1286	struct ieee80211_scan_ies sched_scan_ies = {};
1287	struct cfg80211_chan_def chandef;
1288	int ret, i, iebufsz, num_bands = 0;
1289	u32 rate_masks[NUM_NL80211_BANDS] = {};
1290	u8 bands_used = 0;
1291	u8 *ie;
1292	u32 flags = 0;
1293
1294	iebufsz = local->scan_ies_len + req->ie_len;
1295
1296	lockdep_assert_held(&local->mtx);
1297
1298	if (!local->ops->sched_scan_start)
1299		return -ENOTSUPP;
1300
1301	for (i = 0; i < NUM_NL80211_BANDS; i++) {
1302		if (local->hw.wiphy->bands[i]) {
1303			bands_used |= BIT(i);
1304			rate_masks[i] = (u32) -1;
1305			num_bands++;
1306		}
1307	}
1308
1309	if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
1310		flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
1311
1312	ie = kcalloc(iebufsz, num_bands, GFP_KERNEL);
1313	if (!ie) {
1314		ret = -ENOMEM;
1315		goto out;
1316	}
1317
1318	ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
1319
1320	ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz,
1321				 &sched_scan_ies, req->ie,
1322				 req->ie_len, bands_used, rate_masks, &chandef,
1323				 flags);
 
 
1324
1325	ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
1326	if (ret == 0) {
1327		rcu_assign_pointer(local->sched_scan_sdata, sdata);
1328		rcu_assign_pointer(local->sched_scan_req, req);
1329	}
1330
 
1331	kfree(ie);
1332
1333out:
1334	if (ret) {
1335		/* Clean in case of failure after HW restart or upon resume. */
1336		RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1337		RCU_INIT_POINTER(local->sched_scan_req, NULL);
1338	}
1339
1340	return ret;
1341}
1342
1343int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1344				       struct cfg80211_sched_scan_request *req)
1345{
1346	struct ieee80211_local *local = sdata->local;
1347	int ret;
1348
1349	mutex_lock(&local->mtx);
1350
1351	if (rcu_access_pointer(local->sched_scan_sdata)) {
1352		mutex_unlock(&local->mtx);
1353		return -EBUSY;
1354	}
1355
1356	ret = __ieee80211_request_sched_scan_start(sdata, req);
1357
1358	mutex_unlock(&local->mtx);
1359	return ret;
1360}
1361
1362int ieee80211_request_sched_scan_stop(struct ieee80211_local *local)
1363{
1364	struct ieee80211_sub_if_data *sched_scan_sdata;
1365	int ret = -ENOENT;
1366
1367	mutex_lock(&local->mtx);
1368
1369	if (!local->ops->sched_scan_stop) {
1370		ret = -ENOTSUPP;
1371		goto out;
1372	}
1373
1374	/* We don't want to restart sched scan anymore. */
1375	RCU_INIT_POINTER(local->sched_scan_req, NULL);
1376
1377	sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata,
1378						lockdep_is_held(&local->mtx));
1379	if (sched_scan_sdata) {
1380		ret = drv_sched_scan_stop(local, sched_scan_sdata);
1381		if (!ret)
1382			RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1383	}
1384out:
1385	mutex_unlock(&local->mtx);
1386
1387	return ret;
1388}
1389
1390void ieee80211_sched_scan_results(struct ieee80211_hw *hw)
1391{
1392	struct ieee80211_local *local = hw_to_local(hw);
1393
1394	trace_api_sched_scan_results(local);
1395
1396	cfg80211_sched_scan_results(hw->wiphy, 0);
1397}
1398EXPORT_SYMBOL(ieee80211_sched_scan_results);
1399
1400void ieee80211_sched_scan_end(struct ieee80211_local *local)
1401{
1402	mutex_lock(&local->mtx);
1403
1404	if (!rcu_access_pointer(local->sched_scan_sdata)) {
1405		mutex_unlock(&local->mtx);
1406		return;
1407	}
1408
1409	RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1410
1411	/* If sched scan was aborted by the driver. */
1412	RCU_INIT_POINTER(local->sched_scan_req, NULL);
1413
1414	mutex_unlock(&local->mtx);
1415
1416	cfg80211_sched_scan_stopped(local->hw.wiphy, 0);
1417}
1418
1419void ieee80211_sched_scan_stopped_work(struct work_struct *work)
 
1420{
1421	struct ieee80211_local *local =
1422		container_of(work, struct ieee80211_local,
1423			     sched_scan_stopped_work);
1424
1425	ieee80211_sched_scan_end(local);
1426}
1427
1428void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
1429{
1430	struct ieee80211_local *local = hw_to_local(hw);
1431
1432	trace_api_sched_scan_stopped(local);
1433
1434	/*
1435	 * this shouldn't really happen, so for simplicity
1436	 * simply ignore it, and let mac80211 reconfigure
1437	 * the sched scan later on.
1438	 */
1439	if (local->in_reconfig)
1440		return;
1441
1442	schedule_work(&local->sched_scan_stopped_work);
1443}
1444EXPORT_SYMBOL(ieee80211_sched_scan_stopped);
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);