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) 2018-2020 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.bss_conf.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 ieee802_11_parse_elems(elements, len - baselen, false, &elems,
213 mgmt->bssid, cbss->bssid);
215 /* In case the signal is invalid update the status */
216 signal_valid = channel == cbss->channel;
218 rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL;
220 bss = (void *)cbss->priv;
221 ieee80211_update_bss_from_elems(local, bss, &elems, rx_status, beacon);
223 list_for_each_entry(non_tx_cbss, &cbss->nontrans_list, nontrans_list) {
224 non_tx_bss = (void *)non_tx_cbss->priv;
226 ieee80211_update_bss_from_elems(local, non_tx_bss, &elems,
233 static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata,
234 u32 scan_flags, const u8 *da)
238 /* accept broadcast for OCE */
239 if (scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP &&
240 is_broadcast_ether_addr(da))
242 if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
244 return ether_addr_equal(da, sdata->vif.addr);
247 void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb)
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);
257 if (!ieee80211_is_probe_resp(mgmt->frame_control) &&
258 !ieee80211_is_beacon(mgmt->frame_control) &&
259 !ieee80211_is_s1g_beacon(mgmt->frame_control))
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);
267 min_hdr_len = offsetof(struct ieee80211_ext,
271 if (skb->len < min_hdr_len)
274 sdata1 = rcu_dereference(local->scan_sdata);
275 sdata2 = rcu_dereference(local->sched_scan_sdata);
277 if (likely(!sdata1 && !sdata2))
280 if (test_and_clear_bit(SCAN_BEACON_WAIT, &local->scanning)) {
282 * we were passive scanning because of radar/no-IR, but
283 * the beacon/proberesp rx gives us an opportunity to upgrade
286 set_bit(SCAN_BEACON_DONE, &local->scanning);
287 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
290 if (ieee80211_is_probe_resp(mgmt->frame_control)) {
291 struct cfg80211_scan_request *scan_req;
292 struct cfg80211_sched_scan_request *sched_scan_req;
293 u32 scan_req_flags = 0, sched_scan_req_flags = 0;
295 scan_req = rcu_dereference(local->scan_req);
296 sched_scan_req = rcu_dereference(local->sched_scan_req);
299 scan_req_flags = scan_req->flags;
302 sched_scan_req_flags = sched_scan_req->flags;
304 /* ignore ProbeResp to foreign address or non-bcast (OCE)
305 * unless scanning with randomised address
307 if (!ieee80211_scan_accept_presp(sdata1, scan_req_flags,
309 !ieee80211_scan_accept_presp(sdata2, sched_scan_req_flags,
314 channel = ieee80211_get_channel_khz(local->hw.wiphy,
315 ieee80211_rx_status_to_khz(rx_status));
317 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
320 bss = ieee80211_bss_info_update(local, rx_status,
324 ieee80211_rx_bss_put(local, bss);
328 ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef,
329 enum nl80211_bss_scan_width scan_width)
331 memset(chandef, 0, sizeof(*chandef));
332 switch (scan_width) {
333 case NL80211_BSS_CHAN_WIDTH_5:
334 chandef->width = NL80211_CHAN_WIDTH_5;
336 case NL80211_BSS_CHAN_WIDTH_10:
337 chandef->width = NL80211_CHAN_WIDTH_10;
340 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
345 /* return false if no more work */
346 static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data *sdata)
348 struct ieee80211_local *local = sdata->local;
349 struct cfg80211_scan_request *req;
350 struct cfg80211_chan_def chandef;
352 int i, ielen, n_chans;
355 req = rcu_dereference_protected(local->scan_req,
356 lockdep_is_held(&local->mtx));
358 if (test_bit(SCAN_HW_CANCELLED, &local->scanning))
361 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
362 for (i = 0; i < req->n_channels; i++) {
363 local->hw_scan_req->req.channels[i] = req->channels[i];
364 bands_used |= BIT(req->channels[i]->band);
367 n_chans = req->n_channels;
370 if (local->hw_scan_band == NUM_NL80211_BANDS)
375 for (i = 0; i < req->n_channels; i++) {
376 if (req->channels[i]->band !=
379 local->hw_scan_req->req.channels[n_chans] =
382 bands_used |= BIT(req->channels[i]->band);
385 local->hw_scan_band++;
389 local->hw_scan_req->req.n_channels = n_chans;
390 ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
392 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
393 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
395 ielen = ieee80211_build_preq_ies(sdata,
396 (u8 *)local->hw_scan_req->req.ie,
397 local->hw_scan_ies_bufsize,
398 &local->hw_scan_req->ies,
399 req->ie, req->ie_len,
400 bands_used, req->rates, &chandef,
402 local->hw_scan_req->req.ie_len = ielen;
403 local->hw_scan_req->req.no_cck = req->no_cck;
404 ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr);
405 ether_addr_copy(local->hw_scan_req->req.mac_addr_mask,
407 ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid);
412 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
414 struct ieee80211_local *local = hw_to_local(hw);
415 bool hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning);
416 bool was_scanning = local->scanning;
417 struct cfg80211_scan_request *scan_req;
418 struct ieee80211_sub_if_data *scan_sdata;
419 struct ieee80211_sub_if_data *sdata;
421 lockdep_assert_held(&local->mtx);
424 * It's ok to abort a not-yet-running scan (that
425 * we have one at all will be verified by checking
426 * local->scan_req next), but not to complete it
429 if (WARN_ON(!local->scanning && !aborted))
432 if (WARN_ON(!local->scan_req))
435 scan_sdata = rcu_dereference_protected(local->scan_sdata,
436 lockdep_is_held(&local->mtx));
438 if (hw_scan && !aborted &&
439 !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) &&
440 ieee80211_prep_hw_scan(scan_sdata)) {
443 rc = drv_hw_scan(local,
444 rcu_dereference_protected(local->scan_sdata,
445 lockdep_is_held(&local->mtx)),
451 /* HW scan failed and is going to be reported as aborted,
452 * so clear old scan info.
454 memset(&local->scan_info, 0, sizeof(local->scan_info));
458 kfree(local->hw_scan_req);
459 local->hw_scan_req = NULL;
461 scan_req = rcu_dereference_protected(local->scan_req,
462 lockdep_is_held(&local->mtx));
464 if (scan_req != local->int_scan_req) {
465 local->scan_info.aborted = aborted;
466 cfg80211_scan_done(scan_req, &local->scan_info);
468 RCU_INIT_POINTER(local->scan_req, NULL);
469 RCU_INIT_POINTER(local->scan_sdata, NULL);
472 local->scan_chandef.chan = NULL;
474 /* Set power back to normal operating levels. */
475 ieee80211_hw_config(local, 0);
478 ieee80211_configure_filter(local);
479 drv_sw_scan_complete(local, scan_sdata);
480 ieee80211_offchannel_return(local);
483 ieee80211_recalc_idle(local);
485 ieee80211_mlme_notify_scan_completed(local);
486 ieee80211_ibss_notify_scan_completed(local);
488 /* Requeue all the work that might have been ignored while
489 * the scan was in progress; if there was none this will
490 * just be a no-op for the particular interface.
492 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
493 if (ieee80211_sdata_running(sdata))
494 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
498 ieee80211_start_next_roc(local);
501 void ieee80211_scan_completed(struct ieee80211_hw *hw,
502 struct cfg80211_scan_info *info)
504 struct ieee80211_local *local = hw_to_local(hw);
506 trace_api_scan_completed(local, info->aborted);
508 set_bit(SCAN_COMPLETED, &local->scanning);
510 set_bit(SCAN_ABORTED, &local->scanning);
512 memcpy(&local->scan_info, info, sizeof(*info));
514 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
516 EXPORT_SYMBOL(ieee80211_scan_completed);
518 static int ieee80211_start_sw_scan(struct ieee80211_local *local,
519 struct ieee80211_sub_if_data *sdata)
521 /* Software scan is not supported in multi-channel cases */
522 if (local->use_chanctx)
526 * Hardware/driver doesn't support hw_scan, so use software
527 * scanning instead. First send a nullfunc frame with power save
528 * bit on so that AP will buffer the frames for us while we are not
529 * listening, then send probe requests to each channel and wait for
530 * the responses. After all channels are scanned, tune back to the
531 * original channel and send a nullfunc frame with power save bit
532 * off to trigger the AP to send us all the buffered frames.
534 * Note that while local->sw_scanning is true everything else but
535 * nullfunc frames and probe requests will be dropped in
536 * ieee80211_tx_h_check_assoc().
538 drv_sw_scan_start(local, sdata, local->scan_addr);
540 local->leave_oper_channel_time = jiffies;
541 local->next_scan_state = SCAN_DECISION;
542 local->scan_channel_idx = 0;
544 ieee80211_offchannel_stop_vifs(local);
546 /* ensure nullfunc is transmitted before leaving operating channel */
547 ieee80211_flush_queues(local, NULL, false);
549 ieee80211_configure_filter(local);
551 /* We need to set power level at maximum rate for scanning. */
552 ieee80211_hw_config(local, 0);
554 ieee80211_queue_delayed_work(&local->hw,
555 &local->scan_work, 0);
560 static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata)
562 struct ieee80211_local *local = sdata->local;
563 struct ieee80211_sub_if_data *sdata_iter;
565 if (!ieee80211_is_radar_required(local))
568 if (!regulatory_pre_cac_allowed(local->hw.wiphy))
571 mutex_lock(&local->iflist_mtx);
572 list_for_each_entry(sdata_iter, &local->interfaces, list) {
573 if (sdata_iter->wdev.cac_started) {
574 mutex_unlock(&local->iflist_mtx);
578 mutex_unlock(&local->iflist_mtx);
583 static bool ieee80211_can_scan(struct ieee80211_local *local,
584 struct ieee80211_sub_if_data *sdata)
586 if (!__ieee80211_can_leave_ch(sdata))
589 if (!list_empty(&local->roc_list))
592 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
593 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL)
599 void ieee80211_run_deferred_scan(struct ieee80211_local *local)
601 lockdep_assert_held(&local->mtx);
603 if (!local->scan_req || local->scanning)
606 if (!ieee80211_can_scan(local,
607 rcu_dereference_protected(
609 lockdep_is_held(&local->mtx))))
612 ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
613 round_jiffies_relative(0));
616 static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata,
617 const u8 *src, const u8 *dst,
618 const u8 *ssid, size_t ssid_len,
619 const u8 *ie, size_t ie_len,
620 u32 ratemask, u32 flags, u32 tx_flags,
621 struct ieee80211_channel *channel)
625 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel,
630 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) {
631 struct ieee80211_hdr *hdr = (void *)skb->data;
632 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
633 u16 sn = get_random_u32();
635 info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO;
637 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn));
639 IEEE80211_SKB_CB(skb)->flags |= tx_flags;
640 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band);
644 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
645 unsigned long *next_delay)
648 struct ieee80211_sub_if_data *sdata;
649 struct cfg80211_scan_request *scan_req;
650 enum nl80211_band band = local->hw.conf.chandef.chan->band;
651 u32 flags = 0, tx_flags;
653 scan_req = rcu_dereference_protected(local->scan_req,
654 lockdep_is_held(&local->mtx));
656 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
657 if (scan_req->no_cck)
658 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
659 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
660 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
661 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN)
662 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN;
664 sdata = rcu_dereference_protected(local->scan_sdata,
665 lockdep_is_held(&local->mtx));
667 for (i = 0; i < scan_req->n_ssids; i++)
668 ieee80211_send_scan_probe_req(
669 sdata, local->scan_addr, scan_req->bssid,
670 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len,
671 scan_req->ie, scan_req->ie_len,
672 scan_req->rates[band], flags,
673 tx_flags, local->hw.conf.chandef.chan);
676 * After sending probe requests, wait for probe responses
679 *next_delay = IEEE80211_CHANNEL_TIME;
680 local->next_scan_state = SCAN_DECISION;
683 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
684 struct cfg80211_scan_request *req)
686 struct ieee80211_local *local = sdata->local;
687 bool hw_scan = local->ops->hw_scan;
690 lockdep_assert_held(&local->mtx);
695 if (!__ieee80211_can_leave_ch(sdata))
698 if (!ieee80211_can_scan(local, sdata)) {
699 /* wait for the work to finish/time out */
700 rcu_assign_pointer(local->scan_req, req);
701 rcu_assign_pointer(local->scan_sdata, sdata);
709 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len;
711 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
713 u8 bands_counted = 0;
715 for (i = 0; i < req->n_channels; i++) {
716 if (bands_counted & BIT(req->channels[i]->band))
718 bands_counted |= BIT(req->channels[i]->band);
722 local->hw_scan_ies_bufsize *= n_bands;
725 local->hw_scan_req = kmalloc(
726 sizeof(*local->hw_scan_req) +
727 req->n_channels * sizeof(req->channels[0]) +
728 local->hw_scan_ies_bufsize, GFP_KERNEL);
729 if (!local->hw_scan_req)
732 local->hw_scan_req->req.ssids = req->ssids;
733 local->hw_scan_req->req.n_ssids = req->n_ssids;
734 ies = (u8 *)local->hw_scan_req +
735 sizeof(*local->hw_scan_req) +
736 req->n_channels * sizeof(req->channels[0]);
737 local->hw_scan_req->req.ie = ies;
738 local->hw_scan_req->req.flags = req->flags;
739 eth_broadcast_addr(local->hw_scan_req->req.bssid);
740 local->hw_scan_req->req.duration = req->duration;
741 local->hw_scan_req->req.duration_mandatory =
742 req->duration_mandatory;
744 local->hw_scan_band = 0;
745 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params;
746 local->hw_scan_req->req.scan_6ghz_params =
747 req->scan_6ghz_params;
748 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz;
751 * After allocating local->hw_scan_req, we must
752 * go through until ieee80211_prep_hw_scan(), so
753 * anything that might be changed here and leave
754 * this function early must not go after this
759 rcu_assign_pointer(local->scan_req, req);
760 rcu_assign_pointer(local->scan_sdata, sdata);
762 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
763 get_random_mask_addr(local->scan_addr,
767 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN);
770 __set_bit(SCAN_HW_SCANNING, &local->scanning);
771 } else if ((req->n_channels == 1) &&
772 (req->channels[0] == local->_oper_chandef.chan)) {
774 * If we are scanning only on the operating channel
775 * then we do not need to stop normal activities
777 unsigned long next_delay;
779 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
781 ieee80211_recalc_idle(local);
783 /* Notify driver scan is starting, keep order of operations
784 * same as normal software scan, in case that matters. */
785 drv_sw_scan_start(local, sdata, local->scan_addr);
787 ieee80211_configure_filter(local); /* accept probe-responses */
789 /* We need to ensure power level is at max for scanning. */
790 ieee80211_hw_config(local, 0);
792 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR |
793 IEEE80211_CHAN_RADAR)) ||
795 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
797 set_bit(SCAN_BEACON_WAIT, &local->scanning);
799 ieee80211_scan_state_send_probe(local, &next_delay);
800 next_delay = IEEE80211_CHANNEL_TIME;
803 /* Now, just wait a bit and we are all done! */
804 ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
808 /* Do normal software scan */
809 __set_bit(SCAN_SW_SCANNING, &local->scanning);
812 ieee80211_recalc_idle(local);
815 WARN_ON(!ieee80211_prep_hw_scan(sdata));
816 rc = drv_hw_scan(local, sdata, local->hw_scan_req);
818 rc = ieee80211_start_sw_scan(local, sdata);
822 kfree(local->hw_scan_req);
823 local->hw_scan_req = NULL;
826 ieee80211_recalc_idle(local);
828 local->scan_req = NULL;
829 RCU_INIT_POINTER(local->scan_sdata, NULL);
832 if (hw_scan && rc == 1) {
834 * we can't fall back to software for P2P-GO
835 * as it must update NoA etc.
837 if (ieee80211_vif_type_p2p(&sdata->vif) ==
838 NL80211_IFTYPE_P2P_GO)
848 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
851 * TODO: channel switching also consumes quite some time,
852 * add that delay as well to get a better estimation
854 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR))
855 return IEEE80211_PASSIVE_CHANNEL_TIME;
856 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
859 static void ieee80211_scan_state_decision(struct ieee80211_local *local,
860 unsigned long *next_delay)
862 bool associated = false;
863 bool tx_empty = true;
865 struct ieee80211_sub_if_data *sdata;
866 struct ieee80211_channel *next_chan;
867 enum mac80211_scan_state next_scan_state;
868 struct cfg80211_scan_request *scan_req;
871 * check if at least one STA interface is associated,
872 * check if at least one STA interface has pending tx frames
873 * and grab the lowest used beacon interval
875 mutex_lock(&local->iflist_mtx);
876 list_for_each_entry(sdata, &local->interfaces, list) {
877 if (!ieee80211_sdata_running(sdata))
880 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
881 if (sdata->u.mgd.associated) {
884 if (!qdisc_all_tx_empty(sdata->dev)) {
891 mutex_unlock(&local->iflist_mtx);
893 scan_req = rcu_dereference_protected(local->scan_req,
894 lockdep_is_held(&local->mtx));
896 next_chan = scan_req->channels[local->scan_channel_idx];
899 * we're currently scanning a different channel, let's
900 * see if we can scan another channel without interfering
901 * with the current traffic situation.
903 * Keep good latency, do not stay off-channel more than 125 ms.
906 bad_latency = time_after(jiffies +
907 ieee80211_scan_get_channel_time(next_chan),
908 local->leave_oper_channel_time + HZ / 8);
910 if (associated && !tx_empty) {
911 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY)
912 next_scan_state = SCAN_ABORT;
914 next_scan_state = SCAN_SUSPEND;
915 } else if (associated && bad_latency) {
916 next_scan_state = SCAN_SUSPEND;
918 next_scan_state = SCAN_SET_CHANNEL;
921 local->next_scan_state = next_scan_state;
926 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
927 unsigned long *next_delay)
930 struct ieee80211_channel *chan;
931 enum nl80211_bss_scan_width oper_scan_width;
932 struct cfg80211_scan_request *scan_req;
934 scan_req = rcu_dereference_protected(local->scan_req,
935 lockdep_is_held(&local->mtx));
938 chan = scan_req->channels[local->scan_channel_idx];
940 local->scan_chandef.chan = chan;
941 local->scan_chandef.center_freq1 = chan->center_freq;
942 local->scan_chandef.freq1_offset = chan->freq_offset;
943 local->scan_chandef.center_freq2 = 0;
945 /* For scanning on the S1G band, ignore scan_width (which is constant
946 * across all channels) for now since channel width is specific to each
947 * channel. Detect the required channel width here and likely revisit
948 * later. Maybe scan_width could be used to build the channel scan list?
950 if (chan->band == NL80211_BAND_S1GHZ) {
951 local->scan_chandef.width = ieee80211_s1g_channel_width(chan);
955 switch (scan_req->scan_width) {
956 case NL80211_BSS_CHAN_WIDTH_5:
957 local->scan_chandef.width = NL80211_CHAN_WIDTH_5;
959 case NL80211_BSS_CHAN_WIDTH_10:
960 local->scan_chandef.width = NL80211_CHAN_WIDTH_10;
963 case NL80211_BSS_CHAN_WIDTH_20:
964 /* If scanning on oper channel, use whatever channel-type
965 * is currently in use.
967 oper_scan_width = cfg80211_chandef_to_scan_width(
968 &local->_oper_chandef);
969 if (chan == local->_oper_chandef.chan &&
970 oper_scan_width == scan_req->scan_width)
971 local->scan_chandef = local->_oper_chandef;
973 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
975 case NL80211_BSS_CHAN_WIDTH_1:
976 case NL80211_BSS_CHAN_WIDTH_2:
977 /* shouldn't get here, S1G handled above */
983 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL))
986 /* advance state machine to next channel/band */
987 local->scan_channel_idx++;
990 /* if we skip this channel return to the decision state */
991 local->next_scan_state = SCAN_DECISION;
996 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
997 * (which unfortunately doesn't say _why_ step a) is done,
998 * but it waits for the probe delay or until a frame is
999 * received - and the received frame would update the NAV).
1000 * For now, we do not support waiting until a frame is
1003 * In any case, it is not necessary for a passive scan.
1005 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) ||
1006 !scan_req->n_ssids) {
1007 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
1008 local->next_scan_state = SCAN_DECISION;
1009 if (scan_req->n_ssids)
1010 set_bit(SCAN_BEACON_WAIT, &local->scanning);
1014 /* active scan, send probes */
1015 *next_delay = IEEE80211_PROBE_DELAY;
1016 local->next_scan_state = SCAN_SEND_PROBE;
1019 static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
1020 unsigned long *next_delay)
1022 /* switch back to the operating channel */
1023 local->scan_chandef.chan = NULL;
1024 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
1027 ieee80211_offchannel_return(local);
1029 *next_delay = HZ / 5;
1030 /* afterwards, resume scan & go to next channel */
1031 local->next_scan_state = SCAN_RESUME;
1034 static void ieee80211_scan_state_resume(struct ieee80211_local *local,
1035 unsigned long *next_delay)
1037 ieee80211_offchannel_stop_vifs(local);
1039 if (local->ops->flush) {
1040 ieee80211_flush_queues(local, NULL, false);
1043 *next_delay = HZ / 10;
1045 /* remember when we left the operating channel */
1046 local->leave_oper_channel_time = jiffies;
1048 /* advance to the next channel to be scanned */
1049 local->next_scan_state = SCAN_SET_CHANNEL;
1052 void ieee80211_scan_work(struct work_struct *work)
1054 struct ieee80211_local *local =
1055 container_of(work, struct ieee80211_local, scan_work.work);
1056 struct ieee80211_sub_if_data *sdata;
1057 struct cfg80211_scan_request *scan_req;
1058 unsigned long next_delay = 0;
1061 mutex_lock(&local->mtx);
1063 if (!ieee80211_can_run_worker(local)) {
1068 sdata = rcu_dereference_protected(local->scan_sdata,
1069 lockdep_is_held(&local->mtx));
1070 scan_req = rcu_dereference_protected(local->scan_req,
1071 lockdep_is_held(&local->mtx));
1073 /* When scanning on-channel, the first-callback means completed. */
1074 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) {
1075 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
1079 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) {
1080 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
1084 if (!sdata || !scan_req)
1087 if (!local->scanning) {
1090 RCU_INIT_POINTER(local->scan_req, NULL);
1091 RCU_INIT_POINTER(local->scan_sdata, NULL);
1093 rc = __ieee80211_start_scan(sdata, scan_req);
1095 /* need to complete scan in cfg80211 */
1096 rcu_assign_pointer(local->scan_req, scan_req);
1103 clear_bit(SCAN_BEACON_WAIT, &local->scanning);
1106 * as long as no delay is required advance immediately
1107 * without scheduling a new work
1110 if (!ieee80211_sdata_running(sdata)) {
1115 if (test_and_clear_bit(SCAN_BEACON_DONE, &local->scanning) &&
1116 local->next_scan_state == SCAN_DECISION)
1117 local->next_scan_state = SCAN_SEND_PROBE;
1119 switch (local->next_scan_state) {
1121 /* if no more bands/channels left, complete scan */
1122 if (local->scan_channel_idx >= scan_req->n_channels) {
1126 ieee80211_scan_state_decision(local, &next_delay);
1128 case SCAN_SET_CHANNEL:
1129 ieee80211_scan_state_set_channel(local, &next_delay);
1131 case SCAN_SEND_PROBE:
1132 ieee80211_scan_state_send_probe(local, &next_delay);
1135 ieee80211_scan_state_suspend(local, &next_delay);
1138 ieee80211_scan_state_resume(local, &next_delay);
1144 } while (next_delay == 0);
1146 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay);
1150 __ieee80211_scan_completed(&local->hw, aborted);
1152 mutex_unlock(&local->mtx);
1155 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
1156 struct cfg80211_scan_request *req)
1160 mutex_lock(&sdata->local->mtx);
1161 res = __ieee80211_start_scan(sdata, req);
1162 mutex_unlock(&sdata->local->mtx);
1167 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
1168 const u8 *ssid, u8 ssid_len,
1169 struct ieee80211_channel **channels,
1170 unsigned int n_channels,
1171 enum nl80211_bss_scan_width scan_width)
1173 struct ieee80211_local *local = sdata->local;
1174 int ret = -EBUSY, i, n_ch = 0;
1175 enum nl80211_band band;
1177 mutex_lock(&local->mtx);
1180 if (local->scan_req)
1183 /* fill internal scan request */
1187 for (band = 0; band < NUM_NL80211_BANDS; band++) {
1188 if (!local->hw.wiphy->bands[band] ||
1189 band == NL80211_BAND_6GHZ)
1192 max_n = local->hw.wiphy->bands[band]->n_channels;
1193 for (i = 0; i < max_n; i++) {
1194 struct ieee80211_channel *tmp_ch =
1195 &local->hw.wiphy->bands[band]->channels[i];
1197 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR |
1198 IEEE80211_CHAN_DISABLED))
1201 local->int_scan_req->channels[n_ch] = tmp_ch;
1206 if (WARN_ON_ONCE(n_ch == 0))
1209 local->int_scan_req->n_channels = n_ch;
1211 for (i = 0; i < n_channels; i++) {
1212 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR |
1213 IEEE80211_CHAN_DISABLED))
1216 local->int_scan_req->channels[n_ch] = channels[i];
1220 if (WARN_ON_ONCE(n_ch == 0))
1223 local->int_scan_req->n_channels = n_ch;
1226 local->int_scan_req->ssids = &local->scan_ssid;
1227 local->int_scan_req->n_ssids = 1;
1228 local->int_scan_req->scan_width = scan_width;
1229 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
1230 local->int_scan_req->ssids[0].ssid_len = ssid_len;
1232 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
1234 mutex_unlock(&local->mtx);
1239 * Only call this function when a scan can't be queued -- under RTNL.
1241 void ieee80211_scan_cancel(struct ieee80211_local *local)
1244 * We are canceling software scan, or deferred scan that was not
1245 * yet really started (see __ieee80211_start_scan ).
1247 * Regarding hardware scan:
1248 * - we can not call __ieee80211_scan_completed() as when
1249 * SCAN_HW_SCANNING bit is set this function change
1250 * local->hw_scan_req to operate on 5G band, what race with
1251 * driver which can use local->hw_scan_req
1253 * - we can not cancel scan_work since driver can schedule it
1254 * by ieee80211_scan_completed(..., true) to finish scan
1256 * Hence we only call the cancel_hw_scan() callback, but the low-level
1257 * driver is still responsible for calling ieee80211_scan_completed()
1258 * after the scan was completed/aborted.
1261 mutex_lock(&local->mtx);
1262 if (!local->scan_req)
1266 * We have a scan running and the driver already reported completion,
1267 * but the worker hasn't run yet or is stuck on the mutex - mark it as
1270 if (test_bit(SCAN_HW_SCANNING, &local->scanning) &&
1271 test_bit(SCAN_COMPLETED, &local->scanning)) {
1272 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1276 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
1278 * Make sure that __ieee80211_scan_completed doesn't trigger a
1279 * scan on another band.
1281 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1282 if (local->ops->cancel_hw_scan)
1283 drv_cancel_hw_scan(local,
1284 rcu_dereference_protected(local->scan_sdata,
1285 lockdep_is_held(&local->mtx)));
1290 * If the work is currently running, it must be blocked on
1291 * the mutex, but we'll set scan_sdata = NULL and it'll
1292 * simply exit once it acquires the mutex.
1294 cancel_delayed_work(&local->scan_work);
1296 memset(&local->scan_info, 0, sizeof(local->scan_info));
1297 __ieee80211_scan_completed(&local->hw, true);
1299 mutex_unlock(&local->mtx);
1302 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1303 struct cfg80211_sched_scan_request *req)
1305 struct ieee80211_local *local = sdata->local;
1306 struct ieee80211_scan_ies sched_scan_ies = {};
1307 struct cfg80211_chan_def chandef;
1308 int ret, i, iebufsz, num_bands = 0;
1309 u32 rate_masks[NUM_NL80211_BANDS] = {};
1314 iebufsz = local->scan_ies_len + req->ie_len;
1316 lockdep_assert_held(&local->mtx);
1318 if (!local->ops->sched_scan_start)
1321 for (i = 0; i < NUM_NL80211_BANDS; i++) {
1322 if (local->hw.wiphy->bands[i]) {
1323 bands_used |= BIT(i);
1324 rate_masks[i] = (u32) -1;
1329 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
1330 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
1332 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL);
1338 ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
1340 ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz,
1341 &sched_scan_ies, req->ie,
1342 req->ie_len, bands_used, rate_masks, &chandef,
1345 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
1347 rcu_assign_pointer(local->sched_scan_sdata, sdata);
1348 rcu_assign_pointer(local->sched_scan_req, req);
1355 /* Clean in case of failure after HW restart or upon resume. */
1356 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1357 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1363 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1364 struct cfg80211_sched_scan_request *req)
1366 struct ieee80211_local *local = sdata->local;
1369 mutex_lock(&local->mtx);
1371 if (rcu_access_pointer(local->sched_scan_sdata)) {
1372 mutex_unlock(&local->mtx);
1376 ret = __ieee80211_request_sched_scan_start(sdata, req);
1378 mutex_unlock(&local->mtx);
1382 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local)
1384 struct ieee80211_sub_if_data *sched_scan_sdata;
1387 mutex_lock(&local->mtx);
1389 if (!local->ops->sched_scan_stop) {
1394 /* We don't want to restart sched scan anymore. */
1395 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1397 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata,
1398 lockdep_is_held(&local->mtx));
1399 if (sched_scan_sdata) {
1400 ret = drv_sched_scan_stop(local, sched_scan_sdata);
1402 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1405 mutex_unlock(&local->mtx);
1410 void ieee80211_sched_scan_results(struct ieee80211_hw *hw)
1412 struct ieee80211_local *local = hw_to_local(hw);
1414 trace_api_sched_scan_results(local);
1416 cfg80211_sched_scan_results(hw->wiphy, 0);
1418 EXPORT_SYMBOL(ieee80211_sched_scan_results);
1420 void ieee80211_sched_scan_end(struct ieee80211_local *local)
1422 mutex_lock(&local->mtx);
1424 if (!rcu_access_pointer(local->sched_scan_sdata)) {
1425 mutex_unlock(&local->mtx);
1429 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1431 /* If sched scan was aborted by the driver. */
1432 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1434 mutex_unlock(&local->mtx);
1436 cfg80211_sched_scan_stopped(local->hw.wiphy, 0);
1439 void ieee80211_sched_scan_stopped_work(struct work_struct *work)
1441 struct ieee80211_local *local =
1442 container_of(work, struct ieee80211_local,
1443 sched_scan_stopped_work);
1445 ieee80211_sched_scan_end(local);
1448 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
1450 struct ieee80211_local *local = hw_to_local(hw);
1452 trace_api_sched_scan_stopped(local);
1455 * this shouldn't really happen, so for simplicity
1456 * simply ignore it, and let mac80211 reconfigure
1457 * the sched scan later on.
1459 if (local->in_reconfig)
1462 schedule_work(&local->sched_scan_stopped_work);
1464 EXPORT_SYMBOL(ieee80211_sched_scan_stopped);