1 // SPDX-License-Identifier: GPL-2.0-only
3 * Scanning implementation
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) 2018-2021 Intel Corporation
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>
24 #include "ieee80211_i.h"
25 #include "driver-ops.h"
28 #define IEEE80211_PROBE_DELAY (HZ / 33)
29 #define IEEE80211_CHANNEL_TIME (HZ / 33)
30 #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 9)
32 void ieee80211_rx_bss_put(struct ieee80211_local *local,
33 struct ieee80211_bss *bss)
37 cfg80211_put_bss(local->hw.wiphy,
38 container_of((void *)bss, struct cfg80211_bss, priv));
41 static bool is_uapsd_supported(struct ieee802_11_elems *elems)
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];
52 /* no valid wmm information or parameter element found */
55 return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD;
59 ieee80211_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,
68 bss->device_ts_beacon = rx_status->device_timestamp;
70 bss->device_ts_presp = rx_status->device_timestamp;
72 if (elems->parse_error) {
74 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON;
76 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP;
79 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON;
81 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP;
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;
93 /* replace old supported rates if we get new values */
94 if (!elems->parse_error ||
95 !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) {
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);
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,
113 bss->supp_rates_len = srlen;
114 if (!elems->parse_error)
115 bss->valid_data |= IEEE80211_BSS_VALID_RATES;
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;
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))
133 &sband->bitrates[rx_status->rate_idx];
136 if (elems->vht_cap_elem)
138 le32_to_cpu(elems->vht_cap_elem->vht_cap_info);
140 bss->vht_cap_info = 0;
143 struct ieee80211_bss *
144 ieee80211_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)
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,
157 struct ieee80211_sub_if_data *scan_sdata;
158 struct ieee802_11_elems *elems;
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;
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;
175 bss_meta.chan = channel;
178 scan_sdata = rcu_dereference(local->scan_sdata);
179 if (scan_sdata && scan_sdata->vif.type == NL80211_IFTYPE_STATION &&
180 scan_sdata->vif.cfg.assoc &&
181 ieee80211_have_rx_timestamp(rx_status)) {
182 bss_meta.parent_tsf =
183 ieee80211_calculate_rx_timestamp(local, rx_status,
185 ether_addr_copy(bss_meta.parent_bssid,
186 scan_sdata->vif.bss_conf.bssid);
190 cbss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta,
191 mgmt, len, GFP_ATOMIC);
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;
202 baselen = offsetof(struct ieee80211_ext, u.s1g_beacon.variable);
203 elements = ext->u.s1g_beacon.variable;
205 baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable);
206 elements = mgmt->u.beacon.variable;
212 elems = ieee802_11_parse_elems(elements, len - baselen, false, cbss);
216 /* In case the signal is invalid update the status */
217 signal_valid = channel == cbss->channel;
219 rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL;
221 bss = (void *)cbss->priv;
222 ieee80211_update_bss_from_elems(local, bss, elems, rx_status, beacon);
225 list_for_each_entry(non_tx_cbss, &cbss->nontrans_list, nontrans_list) {
226 non_tx_bss = (void *)non_tx_cbss->priv;
228 elems = ieee802_11_parse_elems(elements, len - baselen, false,
233 ieee80211_update_bss_from_elems(local, non_tx_bss, elems,
241 static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata,
242 u32 scan_flags, const u8 *da)
246 /* accept broadcast for OCE */
247 if (scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP &&
248 is_broadcast_ether_addr(da))
250 if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
252 return ether_addr_equal(da, sdata->vif.addr);
255 void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb)
257 struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
258 struct ieee80211_sub_if_data *sdata1, *sdata2;
259 struct ieee80211_mgmt *mgmt = (void *)skb->data;
260 struct ieee80211_bss *bss;
261 struct ieee80211_channel *channel;
262 size_t min_hdr_len = offsetof(struct ieee80211_mgmt,
263 u.probe_resp.variable);
265 if (!ieee80211_is_probe_resp(mgmt->frame_control) &&
266 !ieee80211_is_beacon(mgmt->frame_control) &&
267 !ieee80211_is_s1g_beacon(mgmt->frame_control))
270 if (ieee80211_is_s1g_beacon(mgmt->frame_control)) {
271 if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
272 min_hdr_len = offsetof(struct ieee80211_ext,
273 u.s1g_short_beacon.variable);
275 min_hdr_len = offsetof(struct ieee80211_ext,
279 if (skb->len < min_hdr_len)
282 sdata1 = rcu_dereference(local->scan_sdata);
283 sdata2 = rcu_dereference(local->sched_scan_sdata);
285 if (likely(!sdata1 && !sdata2))
288 if (test_and_clear_bit(SCAN_BEACON_WAIT, &local->scanning)) {
290 * we were passive scanning because of radar/no-IR, but
291 * the beacon/proberesp rx gives us an opportunity to upgrade
294 set_bit(SCAN_BEACON_DONE, &local->scanning);
295 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
298 if (ieee80211_is_probe_resp(mgmt->frame_control)) {
299 struct cfg80211_scan_request *scan_req;
300 struct cfg80211_sched_scan_request *sched_scan_req;
301 u32 scan_req_flags = 0, sched_scan_req_flags = 0;
303 scan_req = rcu_dereference(local->scan_req);
304 sched_scan_req = rcu_dereference(local->sched_scan_req);
307 scan_req_flags = scan_req->flags;
310 sched_scan_req_flags = sched_scan_req->flags;
312 /* ignore ProbeResp to foreign address or non-bcast (OCE)
313 * unless scanning with randomised address
315 if (!ieee80211_scan_accept_presp(sdata1, scan_req_flags,
317 !ieee80211_scan_accept_presp(sdata2, sched_scan_req_flags,
322 channel = ieee80211_get_channel_khz(local->hw.wiphy,
323 ieee80211_rx_status_to_khz(rx_status));
325 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
328 bss = ieee80211_bss_info_update(local, rx_status,
332 ieee80211_rx_bss_put(local, bss);
336 ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef,
337 enum nl80211_bss_scan_width scan_width)
339 memset(chandef, 0, sizeof(*chandef));
340 switch (scan_width) {
341 case NL80211_BSS_CHAN_WIDTH_5:
342 chandef->width = NL80211_CHAN_WIDTH_5;
344 case NL80211_BSS_CHAN_WIDTH_10:
345 chandef->width = NL80211_CHAN_WIDTH_10;
348 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
353 /* return false if no more work */
354 static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data *sdata)
356 struct ieee80211_local *local = sdata->local;
357 struct cfg80211_scan_request *req;
358 struct cfg80211_chan_def chandef;
360 int i, ielen, n_chans;
363 req = rcu_dereference_protected(local->scan_req,
364 lockdep_is_held(&local->mtx));
366 if (test_bit(SCAN_HW_CANCELLED, &local->scanning))
369 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
370 for (i = 0; i < req->n_channels; i++) {
371 local->hw_scan_req->req.channels[i] = req->channels[i];
372 bands_used |= BIT(req->channels[i]->band);
375 n_chans = req->n_channels;
378 if (local->hw_scan_band == NUM_NL80211_BANDS)
383 for (i = 0; i < req->n_channels; i++) {
384 if (req->channels[i]->band !=
387 local->hw_scan_req->req.channels[n_chans] =
390 bands_used |= BIT(req->channels[i]->band);
393 local->hw_scan_band++;
397 local->hw_scan_req->req.n_channels = n_chans;
398 ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
400 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
401 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
403 ielen = ieee80211_build_preq_ies(sdata,
404 (u8 *)local->hw_scan_req->req.ie,
405 local->hw_scan_ies_bufsize,
406 &local->hw_scan_req->ies,
407 req->ie, req->ie_len,
408 bands_used, req->rates, &chandef,
410 local->hw_scan_req->req.ie_len = ielen;
411 local->hw_scan_req->req.no_cck = req->no_cck;
412 ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr);
413 ether_addr_copy(local->hw_scan_req->req.mac_addr_mask,
415 ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid);
420 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
422 struct ieee80211_local *local = hw_to_local(hw);
423 bool hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning);
424 bool was_scanning = local->scanning;
425 struct cfg80211_scan_request *scan_req;
426 struct ieee80211_sub_if_data *scan_sdata;
427 struct ieee80211_sub_if_data *sdata;
429 lockdep_assert_held(&local->mtx);
432 * It's ok to abort a not-yet-running scan (that
433 * we have one at all will be verified by checking
434 * local->scan_req next), but not to complete it
437 if (WARN_ON(!local->scanning && !aborted))
440 if (WARN_ON(!local->scan_req))
443 scan_sdata = rcu_dereference_protected(local->scan_sdata,
444 lockdep_is_held(&local->mtx));
446 if (hw_scan && !aborted &&
447 !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) &&
448 ieee80211_prep_hw_scan(scan_sdata)) {
451 rc = drv_hw_scan(local,
452 rcu_dereference_protected(local->scan_sdata,
453 lockdep_is_held(&local->mtx)),
459 /* HW scan failed and is going to be reported as aborted,
460 * so clear old scan info.
462 memset(&local->scan_info, 0, sizeof(local->scan_info));
466 kfree(local->hw_scan_req);
467 local->hw_scan_req = NULL;
469 scan_req = rcu_dereference_protected(local->scan_req,
470 lockdep_is_held(&local->mtx));
472 if (scan_req != local->int_scan_req) {
473 local->scan_info.aborted = aborted;
474 cfg80211_scan_done(scan_req, &local->scan_info);
476 RCU_INIT_POINTER(local->scan_req, NULL);
477 RCU_INIT_POINTER(local->scan_sdata, NULL);
480 local->scan_chandef.chan = NULL;
482 /* Set power back to normal operating levels. */
483 ieee80211_hw_config(local, 0);
486 ieee80211_configure_filter(local);
487 drv_sw_scan_complete(local, scan_sdata);
488 ieee80211_offchannel_return(local);
491 ieee80211_recalc_idle(local);
493 ieee80211_mlme_notify_scan_completed(local);
494 ieee80211_ibss_notify_scan_completed(local);
496 /* Requeue all the work that might have been ignored while
497 * the scan was in progress; if there was none this will
498 * just be a no-op for the particular interface.
500 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
501 if (ieee80211_sdata_running(sdata))
502 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
506 ieee80211_start_next_roc(local);
509 void ieee80211_scan_completed(struct ieee80211_hw *hw,
510 struct cfg80211_scan_info *info)
512 struct ieee80211_local *local = hw_to_local(hw);
514 trace_api_scan_completed(local, info->aborted);
516 set_bit(SCAN_COMPLETED, &local->scanning);
518 set_bit(SCAN_ABORTED, &local->scanning);
520 memcpy(&local->scan_info, info, sizeof(*info));
522 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
524 EXPORT_SYMBOL(ieee80211_scan_completed);
526 static int ieee80211_start_sw_scan(struct ieee80211_local *local,
527 struct ieee80211_sub_if_data *sdata)
529 /* Software scan is not supported in multi-channel cases */
530 if (local->use_chanctx)
534 * Hardware/driver doesn't support hw_scan, so use software
535 * scanning instead. First send a nullfunc frame with power save
536 * bit on so that AP will buffer the frames for us while we are not
537 * listening, then send probe requests to each channel and wait for
538 * the responses. After all channels are scanned, tune back to the
539 * original channel and send a nullfunc frame with power save bit
540 * off to trigger the AP to send us all the buffered frames.
542 * Note that while local->sw_scanning is true everything else but
543 * nullfunc frames and probe requests will be dropped in
544 * ieee80211_tx_h_check_assoc().
546 drv_sw_scan_start(local, sdata, local->scan_addr);
548 local->leave_oper_channel_time = jiffies;
549 local->next_scan_state = SCAN_DECISION;
550 local->scan_channel_idx = 0;
552 ieee80211_offchannel_stop_vifs(local);
554 /* ensure nullfunc is transmitted before leaving operating channel */
555 ieee80211_flush_queues(local, NULL, false);
557 ieee80211_configure_filter(local);
559 /* We need to set power level at maximum rate for scanning. */
560 ieee80211_hw_config(local, 0);
562 ieee80211_queue_delayed_work(&local->hw,
563 &local->scan_work, 0);
568 static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata)
570 struct ieee80211_local *local = sdata->local;
571 struct ieee80211_sub_if_data *sdata_iter;
573 if (!ieee80211_is_radar_required(local))
576 if (!regulatory_pre_cac_allowed(local->hw.wiphy))
579 mutex_lock(&local->iflist_mtx);
580 list_for_each_entry(sdata_iter, &local->interfaces, list) {
581 if (sdata_iter->wdev.cac_started) {
582 mutex_unlock(&local->iflist_mtx);
586 mutex_unlock(&local->iflist_mtx);
591 static bool ieee80211_can_scan(struct ieee80211_local *local,
592 struct ieee80211_sub_if_data *sdata)
594 if (!__ieee80211_can_leave_ch(sdata))
597 if (!list_empty(&local->roc_list))
600 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
601 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL)
607 void ieee80211_run_deferred_scan(struct ieee80211_local *local)
609 lockdep_assert_held(&local->mtx);
611 if (!local->scan_req || local->scanning)
614 if (!ieee80211_can_scan(local,
615 rcu_dereference_protected(
617 lockdep_is_held(&local->mtx))))
620 ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
621 round_jiffies_relative(0));
624 static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata,
625 const u8 *src, const u8 *dst,
626 const u8 *ssid, size_t ssid_len,
627 const u8 *ie, size_t ie_len,
628 u32 ratemask, u32 flags, u32 tx_flags,
629 struct ieee80211_channel *channel)
633 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel,
638 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) {
639 struct ieee80211_hdr *hdr = (void *)skb->data;
640 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
641 u16 sn = get_random_u32();
643 info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO;
645 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn));
647 IEEE80211_SKB_CB(skb)->flags |= tx_flags;
648 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band);
652 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
653 unsigned long *next_delay)
656 struct ieee80211_sub_if_data *sdata;
657 struct cfg80211_scan_request *scan_req;
658 enum nl80211_band band = local->hw.conf.chandef.chan->band;
659 u32 flags = 0, tx_flags;
661 scan_req = rcu_dereference_protected(local->scan_req,
662 lockdep_is_held(&local->mtx));
664 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
665 if (scan_req->no_cck)
666 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
667 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
668 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
669 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN)
670 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN;
672 sdata = rcu_dereference_protected(local->scan_sdata,
673 lockdep_is_held(&local->mtx));
675 for (i = 0; i < scan_req->n_ssids; i++)
676 ieee80211_send_scan_probe_req(
677 sdata, local->scan_addr, scan_req->bssid,
678 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len,
679 scan_req->ie, scan_req->ie_len,
680 scan_req->rates[band], flags,
681 tx_flags, local->hw.conf.chandef.chan);
684 * After sending probe requests, wait for probe responses
687 *next_delay = IEEE80211_CHANNEL_TIME;
688 local->next_scan_state = SCAN_DECISION;
691 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
692 struct cfg80211_scan_request *req)
694 struct ieee80211_local *local = sdata->local;
695 bool hw_scan = local->ops->hw_scan;
698 lockdep_assert_held(&local->mtx);
703 if (!__ieee80211_can_leave_ch(sdata))
706 if (!ieee80211_can_scan(local, sdata)) {
707 /* wait for the work to finish/time out */
708 rcu_assign_pointer(local->scan_req, req);
709 rcu_assign_pointer(local->scan_sdata, sdata);
717 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len;
719 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
721 u8 bands_counted = 0;
723 for (i = 0; i < req->n_channels; i++) {
724 if (bands_counted & BIT(req->channels[i]->band))
726 bands_counted |= BIT(req->channels[i]->band);
730 local->hw_scan_ies_bufsize *= n_bands;
733 local->hw_scan_req = kmalloc(
734 sizeof(*local->hw_scan_req) +
735 req->n_channels * sizeof(req->channels[0]) +
736 local->hw_scan_ies_bufsize, GFP_KERNEL);
737 if (!local->hw_scan_req)
740 local->hw_scan_req->req.ssids = req->ssids;
741 local->hw_scan_req->req.n_ssids = req->n_ssids;
742 ies = (u8 *)local->hw_scan_req +
743 sizeof(*local->hw_scan_req) +
744 req->n_channels * sizeof(req->channels[0]);
745 local->hw_scan_req->req.ie = ies;
746 local->hw_scan_req->req.flags = req->flags;
747 eth_broadcast_addr(local->hw_scan_req->req.bssid);
748 local->hw_scan_req->req.duration = req->duration;
749 local->hw_scan_req->req.duration_mandatory =
750 req->duration_mandatory;
752 local->hw_scan_band = 0;
753 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params;
754 local->hw_scan_req->req.scan_6ghz_params =
755 req->scan_6ghz_params;
756 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz;
759 * After allocating local->hw_scan_req, we must
760 * go through until ieee80211_prep_hw_scan(), so
761 * anything that might be changed here and leave
762 * this function early must not go after this
767 rcu_assign_pointer(local->scan_req, req);
768 rcu_assign_pointer(local->scan_sdata, sdata);
770 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
771 get_random_mask_addr(local->scan_addr,
775 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN);
778 __set_bit(SCAN_HW_SCANNING, &local->scanning);
779 } else if ((req->n_channels == 1) &&
780 (req->channels[0] == local->_oper_chandef.chan)) {
782 * If we are scanning only on the operating channel
783 * then we do not need to stop normal activities
785 unsigned long next_delay;
787 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
789 ieee80211_recalc_idle(local);
791 /* Notify driver scan is starting, keep order of operations
792 * same as normal software scan, in case that matters. */
793 drv_sw_scan_start(local, sdata, local->scan_addr);
795 ieee80211_configure_filter(local); /* accept probe-responses */
797 /* We need to ensure power level is at max for scanning. */
798 ieee80211_hw_config(local, 0);
800 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR |
801 IEEE80211_CHAN_RADAR)) ||
803 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
805 set_bit(SCAN_BEACON_WAIT, &local->scanning);
807 ieee80211_scan_state_send_probe(local, &next_delay);
808 next_delay = IEEE80211_CHANNEL_TIME;
811 /* Now, just wait a bit and we are all done! */
812 ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
816 /* Do normal software scan */
817 __set_bit(SCAN_SW_SCANNING, &local->scanning);
820 ieee80211_recalc_idle(local);
823 WARN_ON(!ieee80211_prep_hw_scan(sdata));
824 rc = drv_hw_scan(local, sdata, local->hw_scan_req);
826 rc = ieee80211_start_sw_scan(local, sdata);
830 kfree(local->hw_scan_req);
831 local->hw_scan_req = NULL;
834 ieee80211_recalc_idle(local);
836 local->scan_req = NULL;
837 RCU_INIT_POINTER(local->scan_sdata, NULL);
840 if (hw_scan && rc == 1) {
842 * we can't fall back to software for P2P-GO
843 * as it must update NoA etc.
845 if (ieee80211_vif_type_p2p(&sdata->vif) ==
846 NL80211_IFTYPE_P2P_GO)
856 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
859 * TODO: channel switching also consumes quite some time,
860 * add that delay as well to get a better estimation
862 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR))
863 return IEEE80211_PASSIVE_CHANNEL_TIME;
864 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
867 static void ieee80211_scan_state_decision(struct ieee80211_local *local,
868 unsigned long *next_delay)
870 bool associated = false;
871 bool tx_empty = true;
873 struct ieee80211_sub_if_data *sdata;
874 struct ieee80211_channel *next_chan;
875 enum mac80211_scan_state next_scan_state;
876 struct cfg80211_scan_request *scan_req;
879 * check if at least one STA interface is associated,
880 * check if at least one STA interface has pending tx frames
881 * and grab the lowest used beacon interval
883 mutex_lock(&local->iflist_mtx);
884 list_for_each_entry(sdata, &local->interfaces, list) {
885 if (!ieee80211_sdata_running(sdata))
888 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
889 if (sdata->u.mgd.associated) {
892 if (!qdisc_all_tx_empty(sdata->dev)) {
899 mutex_unlock(&local->iflist_mtx);
901 scan_req = rcu_dereference_protected(local->scan_req,
902 lockdep_is_held(&local->mtx));
904 next_chan = scan_req->channels[local->scan_channel_idx];
907 * we're currently scanning a different channel, let's
908 * see if we can scan another channel without interfering
909 * with the current traffic situation.
911 * Keep good latency, do not stay off-channel more than 125 ms.
914 bad_latency = time_after(jiffies +
915 ieee80211_scan_get_channel_time(next_chan),
916 local->leave_oper_channel_time + HZ / 8);
918 if (associated && !tx_empty) {
919 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY)
920 next_scan_state = SCAN_ABORT;
922 next_scan_state = SCAN_SUSPEND;
923 } else if (associated && bad_latency) {
924 next_scan_state = SCAN_SUSPEND;
926 next_scan_state = SCAN_SET_CHANNEL;
929 local->next_scan_state = next_scan_state;
934 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
935 unsigned long *next_delay)
938 struct ieee80211_channel *chan;
939 enum nl80211_bss_scan_width oper_scan_width;
940 struct cfg80211_scan_request *scan_req;
942 scan_req = rcu_dereference_protected(local->scan_req,
943 lockdep_is_held(&local->mtx));
946 chan = scan_req->channels[local->scan_channel_idx];
948 local->scan_chandef.chan = chan;
949 local->scan_chandef.center_freq1 = chan->center_freq;
950 local->scan_chandef.freq1_offset = chan->freq_offset;
951 local->scan_chandef.center_freq2 = 0;
953 /* For scanning on the S1G band, ignore scan_width (which is constant
954 * across all channels) for now since channel width is specific to each
955 * channel. Detect the required channel width here and likely revisit
956 * later. Maybe scan_width could be used to build the channel scan list?
958 if (chan->band == NL80211_BAND_S1GHZ) {
959 local->scan_chandef.width = ieee80211_s1g_channel_width(chan);
963 switch (scan_req->scan_width) {
964 case NL80211_BSS_CHAN_WIDTH_5:
965 local->scan_chandef.width = NL80211_CHAN_WIDTH_5;
967 case NL80211_BSS_CHAN_WIDTH_10:
968 local->scan_chandef.width = NL80211_CHAN_WIDTH_10;
971 case NL80211_BSS_CHAN_WIDTH_20:
972 /* If scanning on oper channel, use whatever channel-type
973 * is currently in use.
975 oper_scan_width = cfg80211_chandef_to_scan_width(
976 &local->_oper_chandef);
977 if (chan == local->_oper_chandef.chan &&
978 oper_scan_width == scan_req->scan_width)
979 local->scan_chandef = local->_oper_chandef;
981 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
983 case NL80211_BSS_CHAN_WIDTH_1:
984 case NL80211_BSS_CHAN_WIDTH_2:
985 /* shouldn't get here, S1G handled above */
991 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL))
994 /* advance state machine to next channel/band */
995 local->scan_channel_idx++;
998 /* if we skip this channel return to the decision state */
999 local->next_scan_state = SCAN_DECISION;
1004 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
1005 * (which unfortunately doesn't say _why_ step a) is done,
1006 * but it waits for the probe delay or until a frame is
1007 * received - and the received frame would update the NAV).
1008 * For now, we do not support waiting until a frame is
1011 * In any case, it is not necessary for a passive scan.
1013 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) ||
1014 !scan_req->n_ssids) {
1015 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
1016 local->next_scan_state = SCAN_DECISION;
1017 if (scan_req->n_ssids)
1018 set_bit(SCAN_BEACON_WAIT, &local->scanning);
1022 /* active scan, send probes */
1023 *next_delay = IEEE80211_PROBE_DELAY;
1024 local->next_scan_state = SCAN_SEND_PROBE;
1027 static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
1028 unsigned long *next_delay)
1030 /* switch back to the operating channel */
1031 local->scan_chandef.chan = NULL;
1032 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
1035 ieee80211_offchannel_return(local);
1037 *next_delay = HZ / 5;
1038 /* afterwards, resume scan & go to next channel */
1039 local->next_scan_state = SCAN_RESUME;
1042 static void ieee80211_scan_state_resume(struct ieee80211_local *local,
1043 unsigned long *next_delay)
1045 ieee80211_offchannel_stop_vifs(local);
1047 if (local->ops->flush) {
1048 ieee80211_flush_queues(local, NULL, false);
1051 *next_delay = HZ / 10;
1053 /* remember when we left the operating channel */
1054 local->leave_oper_channel_time = jiffies;
1056 /* advance to the next channel to be scanned */
1057 local->next_scan_state = SCAN_SET_CHANNEL;
1060 void ieee80211_scan_work(struct work_struct *work)
1062 struct ieee80211_local *local =
1063 container_of(work, struct ieee80211_local, scan_work.work);
1064 struct ieee80211_sub_if_data *sdata;
1065 struct cfg80211_scan_request *scan_req;
1066 unsigned long next_delay = 0;
1069 mutex_lock(&local->mtx);
1071 if (!ieee80211_can_run_worker(local)) {
1076 sdata = rcu_dereference_protected(local->scan_sdata,
1077 lockdep_is_held(&local->mtx));
1078 scan_req = rcu_dereference_protected(local->scan_req,
1079 lockdep_is_held(&local->mtx));
1081 /* When scanning on-channel, the first-callback means completed. */
1082 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) {
1083 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
1087 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) {
1088 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
1092 if (!sdata || !scan_req)
1095 if (!local->scanning) {
1098 RCU_INIT_POINTER(local->scan_req, NULL);
1099 RCU_INIT_POINTER(local->scan_sdata, NULL);
1101 rc = __ieee80211_start_scan(sdata, scan_req);
1103 /* need to complete scan in cfg80211 */
1104 rcu_assign_pointer(local->scan_req, scan_req);
1111 clear_bit(SCAN_BEACON_WAIT, &local->scanning);
1114 * as long as no delay is required advance immediately
1115 * without scheduling a new work
1118 if (!ieee80211_sdata_running(sdata)) {
1123 if (test_and_clear_bit(SCAN_BEACON_DONE, &local->scanning) &&
1124 local->next_scan_state == SCAN_DECISION)
1125 local->next_scan_state = SCAN_SEND_PROBE;
1127 switch (local->next_scan_state) {
1129 /* if no more bands/channels left, complete scan */
1130 if (local->scan_channel_idx >= scan_req->n_channels) {
1134 ieee80211_scan_state_decision(local, &next_delay);
1136 case SCAN_SET_CHANNEL:
1137 ieee80211_scan_state_set_channel(local, &next_delay);
1139 case SCAN_SEND_PROBE:
1140 ieee80211_scan_state_send_probe(local, &next_delay);
1143 ieee80211_scan_state_suspend(local, &next_delay);
1146 ieee80211_scan_state_resume(local, &next_delay);
1152 } while (next_delay == 0);
1154 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay);
1158 __ieee80211_scan_completed(&local->hw, aborted);
1160 mutex_unlock(&local->mtx);
1163 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
1164 struct cfg80211_scan_request *req)
1168 mutex_lock(&sdata->local->mtx);
1169 res = __ieee80211_start_scan(sdata, req);
1170 mutex_unlock(&sdata->local->mtx);
1175 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
1176 const u8 *ssid, u8 ssid_len,
1177 struct ieee80211_channel **channels,
1178 unsigned int n_channels,
1179 enum nl80211_bss_scan_width scan_width)
1181 struct ieee80211_local *local = sdata->local;
1182 int ret = -EBUSY, i, n_ch = 0;
1183 enum nl80211_band band;
1185 mutex_lock(&local->mtx);
1188 if (local->scan_req)
1191 /* fill internal scan request */
1195 for (band = 0; band < NUM_NL80211_BANDS; band++) {
1196 if (!local->hw.wiphy->bands[band] ||
1197 band == NL80211_BAND_6GHZ)
1200 max_n = local->hw.wiphy->bands[band]->n_channels;
1201 for (i = 0; i < max_n; i++) {
1202 struct ieee80211_channel *tmp_ch =
1203 &local->hw.wiphy->bands[band]->channels[i];
1205 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR |
1206 IEEE80211_CHAN_DISABLED))
1209 local->int_scan_req->channels[n_ch] = tmp_ch;
1214 if (WARN_ON_ONCE(n_ch == 0))
1217 local->int_scan_req->n_channels = n_ch;
1219 for (i = 0; i < n_channels; i++) {
1220 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR |
1221 IEEE80211_CHAN_DISABLED))
1224 local->int_scan_req->channels[n_ch] = channels[i];
1228 if (WARN_ON_ONCE(n_ch == 0))
1231 local->int_scan_req->n_channels = n_ch;
1234 local->int_scan_req->ssids = &local->scan_ssid;
1235 local->int_scan_req->n_ssids = 1;
1236 local->int_scan_req->scan_width = scan_width;
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;
1240 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
1242 mutex_unlock(&local->mtx);
1247 * Only call this function when a scan can't be queued -- under RTNL.
1249 void ieee80211_scan_cancel(struct ieee80211_local *local)
1252 * We are canceling software scan, or deferred scan that was not
1253 * yet really started (see __ieee80211_start_scan ).
1255 * Regarding hardware scan:
1256 * - we can not call __ieee80211_scan_completed() as when
1257 * SCAN_HW_SCANNING bit is set this function change
1258 * local->hw_scan_req to operate on 5G band, what race with
1259 * driver which can use local->hw_scan_req
1261 * - we can not cancel scan_work since driver can schedule it
1262 * by ieee80211_scan_completed(..., true) to finish scan
1264 * Hence we only call the cancel_hw_scan() callback, but the low-level
1265 * driver is still responsible for calling ieee80211_scan_completed()
1266 * after the scan was completed/aborted.
1269 mutex_lock(&local->mtx);
1270 if (!local->scan_req)
1274 * We have a scan running and the driver already reported completion,
1275 * but the worker hasn't run yet or is stuck on the mutex - mark it as
1278 if (test_bit(SCAN_HW_SCANNING, &local->scanning) &&
1279 test_bit(SCAN_COMPLETED, &local->scanning)) {
1280 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1284 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
1286 * Make sure that __ieee80211_scan_completed doesn't trigger a
1287 * scan on another band.
1289 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1290 if (local->ops->cancel_hw_scan)
1291 drv_cancel_hw_scan(local,
1292 rcu_dereference_protected(local->scan_sdata,
1293 lockdep_is_held(&local->mtx)));
1298 * If the work is currently running, it must be blocked on
1299 * the mutex, but we'll set scan_sdata = NULL and it'll
1300 * simply exit once it acquires the mutex.
1302 cancel_delayed_work(&local->scan_work);
1304 memset(&local->scan_info, 0, sizeof(local->scan_info));
1305 __ieee80211_scan_completed(&local->hw, true);
1307 mutex_unlock(&local->mtx);
1310 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1311 struct cfg80211_sched_scan_request *req)
1313 struct ieee80211_local *local = sdata->local;
1314 struct ieee80211_scan_ies sched_scan_ies = {};
1315 struct cfg80211_chan_def chandef;
1316 int ret, i, iebufsz, num_bands = 0;
1317 u32 rate_masks[NUM_NL80211_BANDS] = {};
1322 iebufsz = local->scan_ies_len + req->ie_len;
1324 lockdep_assert_held(&local->mtx);
1326 if (!local->ops->sched_scan_start)
1329 for (i = 0; i < NUM_NL80211_BANDS; i++) {
1330 if (local->hw.wiphy->bands[i]) {
1331 bands_used |= BIT(i);
1332 rate_masks[i] = (u32) -1;
1337 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
1338 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
1340 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL);
1346 ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
1348 ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz,
1349 &sched_scan_ies, req->ie,
1350 req->ie_len, bands_used, rate_masks, &chandef,
1353 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
1355 rcu_assign_pointer(local->sched_scan_sdata, sdata);
1356 rcu_assign_pointer(local->sched_scan_req, req);
1363 /* Clean in case of failure after HW restart or upon resume. */
1364 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1365 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1371 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1372 struct cfg80211_sched_scan_request *req)
1374 struct ieee80211_local *local = sdata->local;
1377 mutex_lock(&local->mtx);
1379 if (rcu_access_pointer(local->sched_scan_sdata)) {
1380 mutex_unlock(&local->mtx);
1384 ret = __ieee80211_request_sched_scan_start(sdata, req);
1386 mutex_unlock(&local->mtx);
1390 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local)
1392 struct ieee80211_sub_if_data *sched_scan_sdata;
1395 mutex_lock(&local->mtx);
1397 if (!local->ops->sched_scan_stop) {
1402 /* We don't want to restart sched scan anymore. */
1403 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1405 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata,
1406 lockdep_is_held(&local->mtx));
1407 if (sched_scan_sdata) {
1408 ret = drv_sched_scan_stop(local, sched_scan_sdata);
1410 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1413 mutex_unlock(&local->mtx);
1418 void ieee80211_sched_scan_results(struct ieee80211_hw *hw)
1420 struct ieee80211_local *local = hw_to_local(hw);
1422 trace_api_sched_scan_results(local);
1424 cfg80211_sched_scan_results(hw->wiphy, 0);
1426 EXPORT_SYMBOL(ieee80211_sched_scan_results);
1428 void ieee80211_sched_scan_end(struct ieee80211_local *local)
1430 mutex_lock(&local->mtx);
1432 if (!rcu_access_pointer(local->sched_scan_sdata)) {
1433 mutex_unlock(&local->mtx);
1437 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1439 /* If sched scan was aborted by the driver. */
1440 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1442 mutex_unlock(&local->mtx);
1444 cfg80211_sched_scan_stopped(local->hw.wiphy, 0);
1447 void ieee80211_sched_scan_stopped_work(struct work_struct *work)
1449 struct ieee80211_local *local =
1450 container_of(work, struct ieee80211_local,
1451 sched_scan_stopped_work);
1453 ieee80211_sched_scan_end(local);
1456 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
1458 struct ieee80211_local *local = hw_to_local(hw);
1460 trace_api_sched_scan_stopped(local);
1463 * this shouldn't really happen, so for simplicity
1464 * simply ignore it, and let mac80211 reconfigure
1465 * the sched scan later on.
1467 if (local->in_reconfig)
1470 schedule_work(&local->sched_scan_stopped_work);
1472 EXPORT_SYMBOL(ieee80211_sched_scan_stopped);