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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);
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) 2018-2021 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.cfg.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 elems = ieee802_11_parse_elems(elements, len - baselen, false, cbss);
213 if (!elems)
214 return NULL;
215
216 /* In case the signal is invalid update the status */
217 signal_valid = channel == cbss->channel;
218 if (!signal_valid)
219 rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL;
220
221 bss = (void *)cbss->priv;
222 ieee80211_update_bss_from_elems(local, bss, elems, rx_status, beacon);
223 kfree(elems);
224
225 list_for_each_entry(non_tx_cbss, &cbss->nontrans_list, nontrans_list) {
226 non_tx_bss = (void *)non_tx_cbss->priv;
227
228 elems = ieee802_11_parse_elems(elements, len - baselen, false,
229 non_tx_cbss);
230 if (!elems)
231 continue;
232
233 ieee80211_update_bss_from_elems(local, non_tx_bss, elems,
234 rx_status, beacon);
235 kfree(elems);
236 }
237
238 return bss;
239}
240
241static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata,
242 u32 scan_flags, const u8 *da)
243{
244 if (!sdata)
245 return false;
246 /* accept broadcast for OCE */
247 if (scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP &&
248 is_broadcast_ether_addr(da))
249 return true;
250 if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
251 return true;
252 return ether_addr_equal(da, sdata->vif.addr);
253}
254
255void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb)
256{
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);
264
265 if (!ieee80211_is_probe_resp(mgmt->frame_control) &&
266 !ieee80211_is_beacon(mgmt->frame_control) &&
267 !ieee80211_is_s1g_beacon(mgmt->frame_control))
268 return;
269
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);
274 else
275 min_hdr_len = offsetof(struct ieee80211_ext,
276 u.s1g_beacon);
277 }
278
279 if (skb->len < min_hdr_len)
280 return;
281
282 sdata1 = rcu_dereference(local->scan_sdata);
283 sdata2 = rcu_dereference(local->sched_scan_sdata);
284
285 if (likely(!sdata1 && !sdata2))
286 return;
287
288 if (test_and_clear_bit(SCAN_BEACON_WAIT, &local->scanning)) {
289 /*
290 * we were passive scanning because of radar/no-IR, but
291 * the beacon/proberesp rx gives us an opportunity to upgrade
292 * to active scan
293 */
294 set_bit(SCAN_BEACON_DONE, &local->scanning);
295 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
296 }
297
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;
302
303 scan_req = rcu_dereference(local->scan_req);
304 sched_scan_req = rcu_dereference(local->sched_scan_req);
305
306 if (scan_req)
307 scan_req_flags = scan_req->flags;
308
309 if (sched_scan_req)
310 sched_scan_req_flags = sched_scan_req->flags;
311
312 /* ignore ProbeResp to foreign address or non-bcast (OCE)
313 * unless scanning with randomised address
314 */
315 if (!ieee80211_scan_accept_presp(sdata1, scan_req_flags,
316 mgmt->da) &&
317 !ieee80211_scan_accept_presp(sdata2, sched_scan_req_flags,
318 mgmt->da))
319 return;
320 }
321
322 channel = ieee80211_get_channel_khz(local->hw.wiphy,
323 ieee80211_rx_status_to_khz(rx_status));
324
325 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
326 return;
327
328 bss = ieee80211_bss_info_update(local, rx_status,
329 mgmt, skb->len,
330 channel);
331 if (bss)
332 ieee80211_rx_bss_put(local, bss);
333}
334
335static void
336ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef,
337 enum nl80211_bss_scan_width scan_width)
338{
339 memset(chandef, 0, sizeof(*chandef));
340 switch (scan_width) {
341 case NL80211_BSS_CHAN_WIDTH_5:
342 chandef->width = NL80211_CHAN_WIDTH_5;
343 break;
344 case NL80211_BSS_CHAN_WIDTH_10:
345 chandef->width = NL80211_CHAN_WIDTH_10;
346 break;
347 default:
348 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
349 break;
350 }
351}
352
353/* return false if no more work */
354static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data *sdata)
355{
356 struct ieee80211_local *local = sdata->local;
357 struct cfg80211_scan_request *req;
358 struct cfg80211_chan_def chandef;
359 u8 bands_used = 0;
360 int i, ielen, n_chans;
361 u32 flags = 0;
362
363 req = rcu_dereference_protected(local->scan_req,
364 lockdep_is_held(&local->mtx));
365
366 if (test_bit(SCAN_HW_CANCELLED, &local->scanning))
367 return false;
368
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);
373 }
374
375 n_chans = req->n_channels;
376 } else {
377 do {
378 if (local->hw_scan_band == NUM_NL80211_BANDS)
379 return false;
380
381 n_chans = 0;
382
383 for (i = 0; i < req->n_channels; i++) {
384 if (req->channels[i]->band !=
385 local->hw_scan_band)
386 continue;
387 local->hw_scan_req->req.channels[n_chans] =
388 req->channels[i];
389 n_chans++;
390 bands_used |= BIT(req->channels[i]->band);
391 }
392
393 local->hw_scan_band++;
394 } while (!n_chans);
395 }
396
397 local->hw_scan_req->req.n_channels = n_chans;
398 ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
399
400 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
401 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
402
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,
409 flags);
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,
414 req->mac_addr_mask);
415 ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid);
416
417 return true;
418}
419
420static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
421{
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;
428
429 lockdep_assert_held(&local->mtx);
430
431 /*
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
435 * successfully.
436 */
437 if (WARN_ON(!local->scanning && !aborted))
438 aborted = true;
439
440 if (WARN_ON(!local->scan_req))
441 return;
442
443 scan_sdata = rcu_dereference_protected(local->scan_sdata,
444 lockdep_is_held(&local->mtx));
445
446 if (hw_scan && !aborted &&
447 !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) &&
448 ieee80211_prep_hw_scan(scan_sdata)) {
449 int rc;
450
451 rc = drv_hw_scan(local,
452 rcu_dereference_protected(local->scan_sdata,
453 lockdep_is_held(&local->mtx)),
454 local->hw_scan_req);
455
456 if (rc == 0)
457 return;
458
459 /* HW scan failed and is going to be reported as aborted,
460 * so clear old scan info.
461 */
462 memset(&local->scan_info, 0, sizeof(local->scan_info));
463 aborted = true;
464 }
465
466 kfree(local->hw_scan_req);
467 local->hw_scan_req = NULL;
468
469 scan_req = rcu_dereference_protected(local->scan_req,
470 lockdep_is_held(&local->mtx));
471
472 RCU_INIT_POINTER(local->scan_req, NULL);
473 RCU_INIT_POINTER(local->scan_sdata, NULL);
474
475 local->scanning = 0;
476 local->scan_chandef.chan = NULL;
477
478 synchronize_rcu();
479
480 if (scan_req != local->int_scan_req) {
481 local->scan_info.aborted = aborted;
482 cfg80211_scan_done(scan_req, &local->scan_info);
483 }
484
485 /* Set power back to normal operating levels. */
486 ieee80211_hw_config(local, 0);
487
488 if (!hw_scan && was_scanning) {
489 ieee80211_configure_filter(local);
490 drv_sw_scan_complete(local, scan_sdata);
491 ieee80211_offchannel_return(local);
492 }
493
494 ieee80211_recalc_idle(local);
495
496 ieee80211_mlme_notify_scan_completed(local);
497 ieee80211_ibss_notify_scan_completed(local);
498
499 /* Requeue all the work that might have been ignored while
500 * the scan was in progress; if there was none this will
501 * just be a no-op for the particular interface.
502 */
503 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
504 if (ieee80211_sdata_running(sdata))
505 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
506 }
507
508 if (was_scanning)
509 ieee80211_start_next_roc(local);
510}
511
512void ieee80211_scan_completed(struct ieee80211_hw *hw,
513 struct cfg80211_scan_info *info)
514{
515 struct ieee80211_local *local = hw_to_local(hw);
516
517 trace_api_scan_completed(local, info->aborted);
518
519 set_bit(SCAN_COMPLETED, &local->scanning);
520 if (info->aborted)
521 set_bit(SCAN_ABORTED, &local->scanning);
522
523 memcpy(&local->scan_info, info, sizeof(*info));
524
525 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
526}
527EXPORT_SYMBOL(ieee80211_scan_completed);
528
529static int ieee80211_start_sw_scan(struct ieee80211_local *local,
530 struct ieee80211_sub_if_data *sdata)
531{
532 /* Software scan is not supported in multi-channel cases */
533 if (local->use_chanctx)
534 return -EOPNOTSUPP;
535
536 /*
537 * Hardware/driver doesn't support hw_scan, so use software
538 * scanning instead. First send a nullfunc frame with power save
539 * bit on so that AP will buffer the frames for us while we are not
540 * listening, then send probe requests to each channel and wait for
541 * the responses. After all channels are scanned, tune back to the
542 * original channel and send a nullfunc frame with power save bit
543 * off to trigger the AP to send us all the buffered frames.
544 *
545 * Note that while local->sw_scanning is true everything else but
546 * nullfunc frames and probe requests will be dropped in
547 * ieee80211_tx_h_check_assoc().
548 */
549 drv_sw_scan_start(local, sdata, local->scan_addr);
550
551 local->leave_oper_channel_time = jiffies;
552 local->next_scan_state = SCAN_DECISION;
553 local->scan_channel_idx = 0;
554
555 ieee80211_offchannel_stop_vifs(local);
556
557 /* ensure nullfunc is transmitted before leaving operating channel */
558 ieee80211_flush_queues(local, NULL, false);
559
560 ieee80211_configure_filter(local);
561
562 /* We need to set power level at maximum rate for scanning. */
563 ieee80211_hw_config(local, 0);
564
565 ieee80211_queue_delayed_work(&local->hw,
566 &local->scan_work, 0);
567
568 return 0;
569}
570
571static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata)
572{
573 struct ieee80211_local *local = sdata->local;
574 struct ieee80211_sub_if_data *sdata_iter;
575
576 if (!ieee80211_is_radar_required(local))
577 return true;
578
579 if (!regulatory_pre_cac_allowed(local->hw.wiphy))
580 return false;
581
582 mutex_lock(&local->iflist_mtx);
583 list_for_each_entry(sdata_iter, &local->interfaces, list) {
584 if (sdata_iter->wdev.cac_started) {
585 mutex_unlock(&local->iflist_mtx);
586 return false;
587 }
588 }
589 mutex_unlock(&local->iflist_mtx);
590
591 return true;
592}
593
594static bool ieee80211_can_scan(struct ieee80211_local *local,
595 struct ieee80211_sub_if_data *sdata)
596{
597 if (!__ieee80211_can_leave_ch(sdata))
598 return false;
599
600 if (!list_empty(&local->roc_list))
601 return false;
602
603 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
604 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL)
605 return false;
606
607 return true;
608}
609
610void ieee80211_run_deferred_scan(struct ieee80211_local *local)
611{
612 lockdep_assert_held(&local->mtx);
613
614 if (!local->scan_req || local->scanning)
615 return;
616
617 if (!ieee80211_can_scan(local,
618 rcu_dereference_protected(
619 local->scan_sdata,
620 lockdep_is_held(&local->mtx))))
621 return;
622
623 ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
624 round_jiffies_relative(0));
625}
626
627static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata,
628 const u8 *src, const u8 *dst,
629 const u8 *ssid, size_t ssid_len,
630 const u8 *ie, size_t ie_len,
631 u32 ratemask, u32 flags, u32 tx_flags,
632 struct ieee80211_channel *channel)
633{
634 struct sk_buff *skb;
635
636 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel,
637 ssid, ssid_len,
638 ie, ie_len, flags);
639
640 if (skb) {
641 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) {
642 struct ieee80211_hdr *hdr = (void *)skb->data;
643 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
644 u16 sn = get_random_u16();
645
646 info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO;
647 hdr->seq_ctrl =
648 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn));
649 }
650 IEEE80211_SKB_CB(skb)->flags |= tx_flags;
651 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band);
652 }
653}
654
655static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
656 unsigned long *next_delay)
657{
658 int i;
659 struct ieee80211_sub_if_data *sdata;
660 struct cfg80211_scan_request *scan_req;
661 enum nl80211_band band = local->hw.conf.chandef.chan->band;
662 u32 flags = 0, tx_flags;
663
664 scan_req = rcu_dereference_protected(local->scan_req,
665 lockdep_is_held(&local->mtx));
666
667 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
668 if (scan_req->no_cck)
669 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
670 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
671 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
672 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN)
673 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN;
674
675 sdata = rcu_dereference_protected(local->scan_sdata,
676 lockdep_is_held(&local->mtx));
677
678 for (i = 0; i < scan_req->n_ssids; i++)
679 ieee80211_send_scan_probe_req(
680 sdata, local->scan_addr, scan_req->bssid,
681 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len,
682 scan_req->ie, scan_req->ie_len,
683 scan_req->rates[band], flags,
684 tx_flags, local->hw.conf.chandef.chan);
685
686 /*
687 * After sending probe requests, wait for probe responses
688 * on the channel.
689 */
690 *next_delay = IEEE80211_CHANNEL_TIME;
691 local->next_scan_state = SCAN_DECISION;
692}
693
694static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
695 struct cfg80211_scan_request *req)
696{
697 struct ieee80211_local *local = sdata->local;
698 bool hw_scan = local->ops->hw_scan;
699 int rc;
700
701 lockdep_assert_held(&local->mtx);
702
703 if (local->scan_req)
704 return -EBUSY;
705
706 if (!__ieee80211_can_leave_ch(sdata))
707 return -EBUSY;
708
709 if (!ieee80211_can_scan(local, sdata)) {
710 /* wait for the work to finish/time out */
711 rcu_assign_pointer(local->scan_req, req);
712 rcu_assign_pointer(local->scan_sdata, sdata);
713 return 0;
714 }
715
716 again:
717 if (hw_scan) {
718 u8 *ies;
719
720 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len;
721
722 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
723 int i, n_bands = 0;
724 u8 bands_counted = 0;
725
726 for (i = 0; i < req->n_channels; i++) {
727 if (bands_counted & BIT(req->channels[i]->band))
728 continue;
729 bands_counted |= BIT(req->channels[i]->band);
730 n_bands++;
731 }
732
733 local->hw_scan_ies_bufsize *= n_bands;
734 }
735
736 local->hw_scan_req = kmalloc(
737 sizeof(*local->hw_scan_req) +
738 req->n_channels * sizeof(req->channels[0]) +
739 local->hw_scan_ies_bufsize, GFP_KERNEL);
740 if (!local->hw_scan_req)
741 return -ENOMEM;
742
743 local->hw_scan_req->req.ssids = req->ssids;
744 local->hw_scan_req->req.n_ssids = req->n_ssids;
745 ies = (u8 *)local->hw_scan_req +
746 sizeof(*local->hw_scan_req) +
747 req->n_channels * sizeof(req->channels[0]);
748 local->hw_scan_req->req.ie = ies;
749 local->hw_scan_req->req.flags = req->flags;
750 eth_broadcast_addr(local->hw_scan_req->req.bssid);
751 local->hw_scan_req->req.duration = req->duration;
752 local->hw_scan_req->req.duration_mandatory =
753 req->duration_mandatory;
754
755 local->hw_scan_band = 0;
756 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params;
757 local->hw_scan_req->req.scan_6ghz_params =
758 req->scan_6ghz_params;
759 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz;
760
761 /*
762 * After allocating local->hw_scan_req, we must
763 * go through until ieee80211_prep_hw_scan(), so
764 * anything that might be changed here and leave
765 * this function early must not go after this
766 * allocation.
767 */
768 }
769
770 rcu_assign_pointer(local->scan_req, req);
771 rcu_assign_pointer(local->scan_sdata, sdata);
772
773 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
774 get_random_mask_addr(local->scan_addr,
775 req->mac_addr,
776 req->mac_addr_mask);
777 else
778 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN);
779
780 if (hw_scan) {
781 __set_bit(SCAN_HW_SCANNING, &local->scanning);
782 } else if ((req->n_channels == 1) &&
783 (req->channels[0] == local->_oper_chandef.chan)) {
784 /*
785 * If we are scanning only on the operating channel
786 * then we do not need to stop normal activities
787 */
788 unsigned long next_delay;
789
790 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
791
792 ieee80211_recalc_idle(local);
793
794 /* Notify driver scan is starting, keep order of operations
795 * same as normal software scan, in case that matters. */
796 drv_sw_scan_start(local, sdata, local->scan_addr);
797
798 ieee80211_configure_filter(local); /* accept probe-responses */
799
800 /* We need to ensure power level is at max for scanning. */
801 ieee80211_hw_config(local, 0);
802
803 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR |
804 IEEE80211_CHAN_RADAR)) ||
805 !req->n_ssids) {
806 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
807 if (req->n_ssids)
808 set_bit(SCAN_BEACON_WAIT, &local->scanning);
809 } else {
810 ieee80211_scan_state_send_probe(local, &next_delay);
811 next_delay = IEEE80211_CHANNEL_TIME;
812 }
813
814 /* Now, just wait a bit and we are all done! */
815 ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
816 next_delay);
817 return 0;
818 } else {
819 /* Do normal software scan */
820 __set_bit(SCAN_SW_SCANNING, &local->scanning);
821 }
822
823 ieee80211_recalc_idle(local);
824
825 if (hw_scan) {
826 WARN_ON(!ieee80211_prep_hw_scan(sdata));
827 rc = drv_hw_scan(local, sdata, local->hw_scan_req);
828 } else {
829 rc = ieee80211_start_sw_scan(local, sdata);
830 }
831
832 if (rc) {
833 kfree(local->hw_scan_req);
834 local->hw_scan_req = NULL;
835 local->scanning = 0;
836
837 ieee80211_recalc_idle(local);
838
839 local->scan_req = NULL;
840 RCU_INIT_POINTER(local->scan_sdata, NULL);
841 }
842
843 if (hw_scan && rc == 1) {
844 /*
845 * we can't fall back to software for P2P-GO
846 * as it must update NoA etc.
847 */
848 if (ieee80211_vif_type_p2p(&sdata->vif) ==
849 NL80211_IFTYPE_P2P_GO)
850 return -EOPNOTSUPP;
851 hw_scan = false;
852 goto again;
853 }
854
855 return rc;
856}
857
858static unsigned long
859ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
860{
861 /*
862 * TODO: channel switching also consumes quite some time,
863 * add that delay as well to get a better estimation
864 */
865 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR))
866 return IEEE80211_PASSIVE_CHANNEL_TIME;
867 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
868}
869
870static void ieee80211_scan_state_decision(struct ieee80211_local *local,
871 unsigned long *next_delay)
872{
873 bool associated = false;
874 bool tx_empty = true;
875 bool bad_latency;
876 struct ieee80211_sub_if_data *sdata;
877 struct ieee80211_channel *next_chan;
878 enum mac80211_scan_state next_scan_state;
879 struct cfg80211_scan_request *scan_req;
880
881 /*
882 * check if at least one STA interface is associated,
883 * check if at least one STA interface has pending tx frames
884 * and grab the lowest used beacon interval
885 */
886 mutex_lock(&local->iflist_mtx);
887 list_for_each_entry(sdata, &local->interfaces, list) {
888 if (!ieee80211_sdata_running(sdata))
889 continue;
890
891 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
892 if (sdata->u.mgd.associated) {
893 associated = true;
894
895 if (!qdisc_all_tx_empty(sdata->dev)) {
896 tx_empty = false;
897 break;
898 }
899 }
900 }
901 }
902 mutex_unlock(&local->iflist_mtx);
903
904 scan_req = rcu_dereference_protected(local->scan_req,
905 lockdep_is_held(&local->mtx));
906
907 next_chan = scan_req->channels[local->scan_channel_idx];
908
909 /*
910 * we're currently scanning a different channel, let's
911 * see if we can scan another channel without interfering
912 * with the current traffic situation.
913 *
914 * Keep good latency, do not stay off-channel more than 125 ms.
915 */
916
917 bad_latency = time_after(jiffies +
918 ieee80211_scan_get_channel_time(next_chan),
919 local->leave_oper_channel_time + HZ / 8);
920
921 if (associated && !tx_empty) {
922 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY)
923 next_scan_state = SCAN_ABORT;
924 else
925 next_scan_state = SCAN_SUSPEND;
926 } else if (associated && bad_latency) {
927 next_scan_state = SCAN_SUSPEND;
928 } else {
929 next_scan_state = SCAN_SET_CHANNEL;
930 }
931
932 local->next_scan_state = next_scan_state;
933
934 *next_delay = 0;
935}
936
937static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
938 unsigned long *next_delay)
939{
940 int skip;
941 struct ieee80211_channel *chan;
942 enum nl80211_bss_scan_width oper_scan_width;
943 struct cfg80211_scan_request *scan_req;
944
945 scan_req = rcu_dereference_protected(local->scan_req,
946 lockdep_is_held(&local->mtx));
947
948 skip = 0;
949 chan = scan_req->channels[local->scan_channel_idx];
950
951 local->scan_chandef.chan = chan;
952 local->scan_chandef.center_freq1 = chan->center_freq;
953 local->scan_chandef.freq1_offset = chan->freq_offset;
954 local->scan_chandef.center_freq2 = 0;
955
956 /* For scanning on the S1G band, ignore scan_width (which is constant
957 * across all channels) for now since channel width is specific to each
958 * channel. Detect the required channel width here and likely revisit
959 * later. Maybe scan_width could be used to build the channel scan list?
960 */
961 if (chan->band == NL80211_BAND_S1GHZ) {
962 local->scan_chandef.width = ieee80211_s1g_channel_width(chan);
963 goto set_channel;
964 }
965
966 switch (scan_req->scan_width) {
967 case NL80211_BSS_CHAN_WIDTH_5:
968 local->scan_chandef.width = NL80211_CHAN_WIDTH_5;
969 break;
970 case NL80211_BSS_CHAN_WIDTH_10:
971 local->scan_chandef.width = NL80211_CHAN_WIDTH_10;
972 break;
973 default:
974 case NL80211_BSS_CHAN_WIDTH_20:
975 /* If scanning on oper channel, use whatever channel-type
976 * is currently in use.
977 */
978 oper_scan_width = cfg80211_chandef_to_scan_width(
979 &local->_oper_chandef);
980 if (chan == local->_oper_chandef.chan &&
981 oper_scan_width == scan_req->scan_width)
982 local->scan_chandef = local->_oper_chandef;
983 else
984 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
985 break;
986 case NL80211_BSS_CHAN_WIDTH_1:
987 case NL80211_BSS_CHAN_WIDTH_2:
988 /* shouldn't get here, S1G handled above */
989 WARN_ON(1);
990 break;
991 }
992
993set_channel:
994 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL))
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 = IEEE80211_PASSIVE_CHANNEL_TIME;
1019 local->next_scan_state = SCAN_DECISION;
1020 if (scan_req->n_ssids)
1021 set_bit(SCAN_BEACON_WAIT, &local->scanning);
1022 return;
1023 }
1024
1025 /* active scan, send probes */
1026 *next_delay = IEEE80211_PROBE_DELAY;
1027 local->next_scan_state = SCAN_SEND_PROBE;
1028}
1029
1030static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
1031 unsigned long *next_delay)
1032{
1033 /* switch back to the operating channel */
1034 local->scan_chandef.chan = NULL;
1035 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
1036
1037 /* disable PS */
1038 ieee80211_offchannel_return(local);
1039
1040 *next_delay = HZ / 5;
1041 /* afterwards, resume scan & go to next channel */
1042 local->next_scan_state = SCAN_RESUME;
1043}
1044
1045static void ieee80211_scan_state_resume(struct ieee80211_local *local,
1046 unsigned long *next_delay)
1047{
1048 ieee80211_offchannel_stop_vifs(local);
1049
1050 if (local->ops->flush) {
1051 ieee80211_flush_queues(local, NULL, false);
1052 *next_delay = 0;
1053 } else
1054 *next_delay = HZ / 10;
1055
1056 /* remember when we left the operating channel */
1057 local->leave_oper_channel_time = jiffies;
1058
1059 /* advance to the next channel to be scanned */
1060 local->next_scan_state = SCAN_SET_CHANNEL;
1061}
1062
1063void ieee80211_scan_work(struct work_struct *work)
1064{
1065 struct ieee80211_local *local =
1066 container_of(work, struct ieee80211_local, scan_work.work);
1067 struct ieee80211_sub_if_data *sdata;
1068 struct cfg80211_scan_request *scan_req;
1069 unsigned long next_delay = 0;
1070 bool aborted;
1071
1072 mutex_lock(&local->mtx);
1073
1074 if (!ieee80211_can_run_worker(local)) {
1075 aborted = true;
1076 goto out_complete;
1077 }
1078
1079 sdata = rcu_dereference_protected(local->scan_sdata,
1080 lockdep_is_held(&local->mtx));
1081 scan_req = rcu_dereference_protected(local->scan_req,
1082 lockdep_is_held(&local->mtx));
1083
1084 /* When scanning on-channel, the first-callback means completed. */
1085 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) {
1086 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
1087 goto out_complete;
1088 }
1089
1090 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) {
1091 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
1092 goto out_complete;
1093 }
1094
1095 if (!sdata || !scan_req)
1096 goto out;
1097
1098 if (!local->scanning) {
1099 int rc;
1100
1101 RCU_INIT_POINTER(local->scan_req, NULL);
1102 RCU_INIT_POINTER(local->scan_sdata, NULL);
1103
1104 rc = __ieee80211_start_scan(sdata, scan_req);
1105 if (rc) {
1106 /* need to complete scan in cfg80211 */
1107 rcu_assign_pointer(local->scan_req, scan_req);
1108 aborted = true;
1109 goto out_complete;
1110 } else
1111 goto out;
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 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay);
1158 goto out;
1159
1160out_complete:
1161 __ieee80211_scan_completed(&local->hw, aborted);
1162out:
1163 mutex_unlock(&local->mtx);
1164}
1165
1166int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
1167 struct cfg80211_scan_request *req)
1168{
1169 int res;
1170
1171 mutex_lock(&sdata->local->mtx);
1172 res = __ieee80211_start_scan(sdata, req);
1173 mutex_unlock(&sdata->local->mtx);
1174
1175 return res;
1176}
1177
1178int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
1179 const u8 *ssid, u8 ssid_len,
1180 struct ieee80211_channel **channels,
1181 unsigned int n_channels,
1182 enum nl80211_bss_scan_width scan_width)
1183{
1184 struct ieee80211_local *local = sdata->local;
1185 int ret = -EBUSY, i, n_ch = 0;
1186 enum nl80211_band band;
1187
1188 mutex_lock(&local->mtx);
1189
1190 /* busy scanning */
1191 if (local->scan_req)
1192 goto unlock;
1193
1194 /* fill internal scan request */
1195 if (!channels) {
1196 int max_n;
1197
1198 for (band = 0; band < NUM_NL80211_BANDS; band++) {
1199 if (!local->hw.wiphy->bands[band] ||
1200 band == NL80211_BAND_6GHZ)
1201 continue;
1202
1203 max_n = local->hw.wiphy->bands[band]->n_channels;
1204 for (i = 0; i < max_n; i++) {
1205 struct ieee80211_channel *tmp_ch =
1206 &local->hw.wiphy->bands[band]->channels[i];
1207
1208 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR |
1209 IEEE80211_CHAN_DISABLED))
1210 continue;
1211
1212 local->int_scan_req->channels[n_ch] = tmp_ch;
1213 n_ch++;
1214 }
1215 }
1216
1217 if (WARN_ON_ONCE(n_ch == 0))
1218 goto unlock;
1219
1220 local->int_scan_req->n_channels = n_ch;
1221 } else {
1222 for (i = 0; i < n_channels; i++) {
1223 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR |
1224 IEEE80211_CHAN_DISABLED))
1225 continue;
1226
1227 local->int_scan_req->channels[n_ch] = channels[i];
1228 n_ch++;
1229 }
1230
1231 if (WARN_ON_ONCE(n_ch == 0))
1232 goto unlock;
1233
1234 local->int_scan_req->n_channels = n_ch;
1235 }
1236
1237 local->int_scan_req->ssids = &local->scan_ssid;
1238 local->int_scan_req->n_ssids = 1;
1239 local->int_scan_req->scan_width = scan_width;
1240 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
1241 local->int_scan_req->ssids[0].ssid_len = ssid_len;
1242
1243 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
1244 unlock:
1245 mutex_unlock(&local->mtx);
1246 return ret;
1247}
1248
1249/*
1250 * Only call this function when a scan can't be queued -- under RTNL.
1251 */
1252void ieee80211_scan_cancel(struct ieee80211_local *local)
1253{
1254 /*
1255 * We are canceling software scan, or deferred scan that was not
1256 * yet really started (see __ieee80211_start_scan ).
1257 *
1258 * Regarding hardware scan:
1259 * - we can not call __ieee80211_scan_completed() as when
1260 * SCAN_HW_SCANNING bit is set this function change
1261 * local->hw_scan_req to operate on 5G band, what race with
1262 * driver which can use local->hw_scan_req
1263 *
1264 * - we can not cancel scan_work since driver can schedule it
1265 * by ieee80211_scan_completed(..., true) to finish scan
1266 *
1267 * Hence we only call the cancel_hw_scan() callback, but the low-level
1268 * driver is still responsible for calling ieee80211_scan_completed()
1269 * after the scan was completed/aborted.
1270 */
1271
1272 mutex_lock(&local->mtx);
1273 if (!local->scan_req)
1274 goto out;
1275
1276 /*
1277 * We have a scan running and the driver already reported completion,
1278 * but the worker hasn't run yet or is stuck on the mutex - mark it as
1279 * cancelled.
1280 */
1281 if (test_bit(SCAN_HW_SCANNING, &local->scanning) &&
1282 test_bit(SCAN_COMPLETED, &local->scanning)) {
1283 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1284 goto out;
1285 }
1286
1287 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
1288 /*
1289 * Make sure that __ieee80211_scan_completed doesn't trigger a
1290 * scan on another band.
1291 */
1292 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1293 if (local->ops->cancel_hw_scan)
1294 drv_cancel_hw_scan(local,
1295 rcu_dereference_protected(local->scan_sdata,
1296 lockdep_is_held(&local->mtx)));
1297 goto out;
1298 }
1299
1300 /*
1301 * If the work is currently running, it must be blocked on
1302 * the mutex, but we'll set scan_sdata = NULL and it'll
1303 * simply exit once it acquires the mutex.
1304 */
1305 cancel_delayed_work(&local->scan_work);
1306 /* and clean up */
1307 memset(&local->scan_info, 0, sizeof(local->scan_info));
1308 __ieee80211_scan_completed(&local->hw, true);
1309out:
1310 mutex_unlock(&local->mtx);
1311}
1312
1313int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1314 struct cfg80211_sched_scan_request *req)
1315{
1316 struct ieee80211_local *local = sdata->local;
1317 struct ieee80211_scan_ies sched_scan_ies = {};
1318 struct cfg80211_chan_def chandef;
1319 int ret, i, iebufsz, num_bands = 0;
1320 u32 rate_masks[NUM_NL80211_BANDS] = {};
1321 u8 bands_used = 0;
1322 u8 *ie;
1323 u32 flags = 0;
1324
1325 iebufsz = local->scan_ies_len + req->ie_len;
1326
1327 lockdep_assert_held(&local->mtx);
1328
1329 if (!local->ops->sched_scan_start)
1330 return -ENOTSUPP;
1331
1332 for (i = 0; i < NUM_NL80211_BANDS; i++) {
1333 if (local->hw.wiphy->bands[i]) {
1334 bands_used |= BIT(i);
1335 rate_masks[i] = (u32) -1;
1336 num_bands++;
1337 }
1338 }
1339
1340 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
1341 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
1342
1343 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL);
1344 if (!ie) {
1345 ret = -ENOMEM;
1346 goto out;
1347 }
1348
1349 ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
1350
1351 ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz,
1352 &sched_scan_ies, req->ie,
1353 req->ie_len, bands_used, rate_masks, &chandef,
1354 flags);
1355
1356 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
1357 if (ret == 0) {
1358 rcu_assign_pointer(local->sched_scan_sdata, sdata);
1359 rcu_assign_pointer(local->sched_scan_req, req);
1360 }
1361
1362 kfree(ie);
1363
1364out:
1365 if (ret) {
1366 /* Clean in case of failure after HW restart or upon resume. */
1367 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1368 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1369 }
1370
1371 return ret;
1372}
1373
1374int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1375 struct cfg80211_sched_scan_request *req)
1376{
1377 struct ieee80211_local *local = sdata->local;
1378 int ret;
1379
1380 mutex_lock(&local->mtx);
1381
1382 if (rcu_access_pointer(local->sched_scan_sdata)) {
1383 mutex_unlock(&local->mtx);
1384 return -EBUSY;
1385 }
1386
1387 ret = __ieee80211_request_sched_scan_start(sdata, req);
1388
1389 mutex_unlock(&local->mtx);
1390 return ret;
1391}
1392
1393int ieee80211_request_sched_scan_stop(struct ieee80211_local *local)
1394{
1395 struct ieee80211_sub_if_data *sched_scan_sdata;
1396 int ret = -ENOENT;
1397
1398 mutex_lock(&local->mtx);
1399
1400 if (!local->ops->sched_scan_stop) {
1401 ret = -ENOTSUPP;
1402 goto out;
1403 }
1404
1405 /* We don't want to restart sched scan anymore. */
1406 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1407
1408 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata,
1409 lockdep_is_held(&local->mtx));
1410 if (sched_scan_sdata) {
1411 ret = drv_sched_scan_stop(local, sched_scan_sdata);
1412 if (!ret)
1413 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1414 }
1415out:
1416 mutex_unlock(&local->mtx);
1417
1418 return ret;
1419}
1420
1421void ieee80211_sched_scan_results(struct ieee80211_hw *hw)
1422{
1423 struct ieee80211_local *local = hw_to_local(hw);
1424
1425 trace_api_sched_scan_results(local);
1426
1427 cfg80211_sched_scan_results(hw->wiphy, 0);
1428}
1429EXPORT_SYMBOL(ieee80211_sched_scan_results);
1430
1431void ieee80211_sched_scan_end(struct ieee80211_local *local)
1432{
1433 mutex_lock(&local->mtx);
1434
1435 if (!rcu_access_pointer(local->sched_scan_sdata)) {
1436 mutex_unlock(&local->mtx);
1437 return;
1438 }
1439
1440 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1441
1442 /* If sched scan was aborted by the driver. */
1443 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1444
1445 mutex_unlock(&local->mtx);
1446
1447 cfg80211_sched_scan_stopped(local->hw.wiphy, 0);
1448}
1449
1450void ieee80211_sched_scan_stopped_work(struct work_struct *work)
1451{
1452 struct ieee80211_local *local =
1453 container_of(work, struct ieee80211_local,
1454 sched_scan_stopped_work);
1455
1456 ieee80211_sched_scan_end(local);
1457}
1458
1459void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
1460{
1461 struct ieee80211_local *local = hw_to_local(hw);
1462
1463 trace_api_sched_scan_stopped(local);
1464
1465 /*
1466 * this shouldn't really happen, so for simplicity
1467 * simply ignore it, and let mac80211 reconfigure
1468 * the sched scan later on.
1469 */
1470 if (local->in_reconfig)
1471 return;
1472
1473 schedule_work(&local->sched_scan_stopped_work);
1474}
1475EXPORT_SYMBOL(ieee80211_sched_scan_stopped);