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) 2018-2025 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
ieee80211_rx_bss_put(struct ieee80211_local * local,struct ieee80211_bss * bss)32 void 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
is_uapsd_supported(struct ieee802_11_elems * elems)41 static 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
58 struct inform_bss_update_data {
59 struct ieee80211_rx_status *rx_status;
60 bool beacon;
61 };
62
ieee80211_inform_bss(struct wiphy * wiphy,struct cfg80211_bss * cbss,const struct cfg80211_bss_ies * ies,void * data)63 void 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
163 struct ieee80211_bss *
ieee80211_bss_info_update(struct ieee80211_local * local,struct ieee80211_rx_status * rx_status,struct ieee80211_mgmt * mgmt,size_t len,struct ieee80211_channel * channel)164 ieee80211_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
ieee80211_scan_accept_presp(struct ieee80211_sub_if_data * sdata,struct ieee80211_channel * channel,u32 scan_flags,const u8 * da)239 static 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 struct ieee80211_link_data *link_sdata;
244 u8 link_id;
245
246 if (!sdata)
247 return false;
248
249 /* accept broadcast on 6 GHz and for OCE */
250 if (is_broadcast_ether_addr(da) &&
251 (channel->band == NL80211_BAND_6GHZ ||
252 scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP))
253 return true;
254
255 if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
256 return true;
257
258 if (ether_addr_equal(da, sdata->vif.addr))
259 return true;
260
261 for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) {
262 link_sdata = rcu_dereference(sdata->link[link_id]);
263 if (!link_sdata)
264 continue;
265
266 if (ether_addr_equal(da, link_sdata->conf->addr))
267 return true;
268 }
269
270 return false;
271 }
272
ieee80211_scan_rx(struct ieee80211_local * local,struct sk_buff * skb)273 void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb)
274 {
275 struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
276 struct ieee80211_mgmt *mgmt = (void *)skb->data;
277 struct ieee80211_bss *bss;
278 struct ieee80211_channel *channel;
279 struct ieee80211_ext *ext;
280 size_t min_hdr_len = offsetof(struct ieee80211_mgmt,
281 u.probe_resp.variable);
282
283 if (!ieee80211_is_probe_resp(mgmt->frame_control) &&
284 !ieee80211_is_beacon(mgmt->frame_control) &&
285 !ieee80211_is_s1g_beacon(mgmt->frame_control))
286 return;
287
288 if (ieee80211_is_s1g_beacon(mgmt->frame_control)) {
289 ext = (struct ieee80211_ext *)mgmt;
290 min_hdr_len =
291 offsetof(struct ieee80211_ext, u.s1g_beacon.variable) +
292 ieee80211_s1g_optional_len(ext->frame_control);
293 }
294
295 if (skb->len < min_hdr_len)
296 return;
297
298 if (test_and_clear_bit(SCAN_BEACON_WAIT, &local->scanning)) {
299 /*
300 * we were passive scanning because of radar/no-IR, but
301 * the beacon/proberesp rx gives us an opportunity to upgrade
302 * to active scan
303 */
304 set_bit(SCAN_BEACON_DONE, &local->scanning);
305 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 0);
306 }
307
308 channel = ieee80211_get_channel_khz(local->hw.wiphy,
309 ieee80211_rx_status_to_khz(rx_status));
310
311 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
312 return;
313
314 if (ieee80211_is_probe_resp(mgmt->frame_control)) {
315 struct ieee80211_sub_if_data *sdata1, *sdata2;
316 struct cfg80211_scan_request *scan_req;
317 struct cfg80211_sched_scan_request *sched_scan_req;
318 u32 scan_req_flags = 0, sched_scan_req_flags = 0;
319
320 sdata1 = rcu_dereference(local->scan_sdata);
321 sdata2 = rcu_dereference(local->sched_scan_sdata);
322
323 if (likely(!sdata1 && !sdata2))
324 return;
325
326 scan_req = rcu_dereference(local->scan_req);
327 sched_scan_req = rcu_dereference(local->sched_scan_req);
328
329 if (scan_req)
330 scan_req_flags = scan_req->flags;
331
332 if (sched_scan_req)
333 sched_scan_req_flags = sched_scan_req->flags;
334
335 /* ignore ProbeResp to foreign address or non-bcast (OCE)
336 * unless scanning with randomised address
337 */
338 if (!ieee80211_scan_accept_presp(sdata1, channel,
339 scan_req_flags,
340 mgmt->da) &&
341 !ieee80211_scan_accept_presp(sdata2, channel,
342 sched_scan_req_flags,
343 mgmt->da))
344 return;
345 } else {
346 /* Beacons are expected only with broadcast address */
347 if (!is_broadcast_ether_addr(mgmt->da))
348 return;
349 }
350
351 /* Do not update the BSS table in case of only monitor interfaces */
352 if (local->open_count == local->monitors)
353 return;
354
355 bss = ieee80211_bss_info_update(local, rx_status,
356 mgmt, skb->len,
357 channel);
358 if (bss)
359 ieee80211_rx_bss_put(local, bss);
360 }
361
ieee80211_prepare_scan_chandef(struct cfg80211_chan_def * chandef)362 static void ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef)
363 {
364 memset(chandef, 0, sizeof(*chandef));
365
366 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
367 }
368
369 /* return false if no more work */
ieee80211_prep_hw_scan(struct ieee80211_sub_if_data * sdata)370 static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data *sdata)
371 {
372 struct ieee80211_local *local = sdata->local;
373 struct cfg80211_scan_request *req;
374 struct cfg80211_chan_def chandef;
375 u8 bands_used = 0;
376 int i, ielen;
377 u32 *n_chans;
378 u32 flags = 0;
379
380 req = rcu_dereference_protected(local->scan_req,
381 lockdep_is_held(&local->hw.wiphy->mtx));
382
383 if (test_bit(SCAN_HW_CANCELLED, &local->scanning))
384 return false;
385
386 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
387 local->hw_scan_req->req.n_channels = req->n_channels;
388
389 for (i = 0; i < req->n_channels; i++) {
390 local->hw_scan_req->req.channels[i] = req->channels[i];
391 bands_used |= BIT(req->channels[i]->band);
392 }
393 } else {
394 do {
395 if (local->hw_scan_band == NUM_NL80211_BANDS)
396 return false;
397
398 n_chans = &local->hw_scan_req->req.n_channels;
399 *n_chans = 0;
400
401 for (i = 0; i < req->n_channels; i++) {
402 if (req->channels[i]->band !=
403 local->hw_scan_band)
404 continue;
405 local->hw_scan_req->req.channels[(*n_chans)++] =
406 req->channels[i];
407
408 bands_used |= BIT(req->channels[i]->band);
409 }
410
411 local->hw_scan_band++;
412 } while (!*n_chans);
413 }
414
415 ieee80211_prepare_scan_chandef(&chandef);
416
417 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
418 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
419
420 ielen = ieee80211_build_preq_ies(sdata,
421 (u8 *)local->hw_scan_req->req.ie,
422 local->hw_scan_ies_bufsize,
423 &local->hw_scan_req->ies,
424 req->ie, req->ie_len,
425 bands_used, req->rates, &chandef,
426 flags);
427 if (ielen < 0)
428 return false;
429 local->hw_scan_req->req.ie_len = ielen;
430 local->hw_scan_req->req.no_cck = req->no_cck;
431 ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr);
432 ether_addr_copy(local->hw_scan_req->req.mac_addr_mask,
433 req->mac_addr_mask);
434 ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid);
435
436 return true;
437 }
438
__ieee80211_scan_completed(struct ieee80211_hw * hw,bool aborted)439 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
440 {
441 struct ieee80211_local *local = hw_to_local(hw);
442 bool hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning);
443 bool was_scanning = local->scanning;
444 struct cfg80211_scan_request *scan_req;
445 struct ieee80211_sub_if_data *scan_sdata;
446 struct ieee80211_sub_if_data *sdata;
447
448 lockdep_assert_wiphy(local->hw.wiphy);
449
450 /*
451 * It's ok to abort a not-yet-running scan (that
452 * we have one at all will be verified by checking
453 * local->scan_req next), but not to complete it
454 * successfully.
455 */
456 if (WARN_ON(!local->scanning && !aborted))
457 aborted = true;
458
459 if (WARN_ON(!local->scan_req))
460 return;
461
462 scan_sdata = rcu_dereference_protected(local->scan_sdata,
463 lockdep_is_held(&local->hw.wiphy->mtx));
464
465 if (hw_scan && !aborted &&
466 !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) &&
467 ieee80211_prep_hw_scan(scan_sdata)) {
468 int rc;
469
470 rc = drv_hw_scan(local,
471 rcu_dereference_protected(local->scan_sdata,
472 lockdep_is_held(&local->hw.wiphy->mtx)),
473 local->hw_scan_req);
474
475 if (rc == 0)
476 return;
477
478 /* HW scan failed and is going to be reported as aborted,
479 * so clear old scan info.
480 */
481 memset(&local->scan_info, 0, sizeof(local->scan_info));
482 aborted = true;
483 }
484
485 kfree(local->hw_scan_req);
486 local->hw_scan_req = NULL;
487
488 scan_req = rcu_dereference_protected(local->scan_req,
489 lockdep_is_held(&local->hw.wiphy->mtx));
490
491 RCU_INIT_POINTER(local->scan_req, NULL);
492 RCU_INIT_POINTER(local->scan_sdata, NULL);
493
494 local->scanning = 0;
495 local->scan_chandef.chan = NULL;
496
497 synchronize_rcu();
498
499 if (scan_req != local->int_scan_req) {
500 local->scan_info.aborted = aborted;
501 cfg80211_scan_done(scan_req, &local->scan_info);
502 }
503
504 /* Set power back to normal operating levels. */
505 ieee80211_hw_conf_chan(local);
506
507 if (!hw_scan && was_scanning) {
508 ieee80211_configure_filter(local);
509 drv_sw_scan_complete(local, scan_sdata);
510 ieee80211_offchannel_return(local);
511 }
512
513 ieee80211_recalc_idle(local);
514
515 ieee80211_mlme_notify_scan_completed(local);
516 ieee80211_ibss_notify_scan_completed(local);
517
518 /* Requeue all the work that might have been ignored while
519 * the scan was in progress; if there was none this will
520 * just be a no-op for the particular interface.
521 */
522 list_for_each_entry(sdata, &local->interfaces, list) {
523 if (ieee80211_sdata_running(sdata))
524 wiphy_work_queue(sdata->local->hw.wiphy, &sdata->work);
525 }
526
527 if (was_scanning)
528 ieee80211_start_next_roc(local);
529 }
530
ieee80211_scan_completed(struct ieee80211_hw * hw,struct cfg80211_scan_info * info)531 void ieee80211_scan_completed(struct ieee80211_hw *hw,
532 struct cfg80211_scan_info *info)
533 {
534 struct ieee80211_local *local = hw_to_local(hw);
535
536 trace_api_scan_completed(local, info->aborted);
537
538 set_bit(SCAN_COMPLETED, &local->scanning);
539 if (info->aborted)
540 set_bit(SCAN_ABORTED, &local->scanning);
541
542 memcpy(&local->scan_info, info, sizeof(*info));
543
544 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 0);
545 }
546 EXPORT_SYMBOL(ieee80211_scan_completed);
547
ieee80211_start_sw_scan(struct ieee80211_local * local,struct ieee80211_sub_if_data * sdata)548 static int ieee80211_start_sw_scan(struct ieee80211_local *local,
549 struct ieee80211_sub_if_data *sdata)
550 {
551 /* Software scan is not supported in multi-channel cases */
552 if (!local->emulate_chanctx)
553 return -EOPNOTSUPP;
554
555 /*
556 * Hardware/driver doesn't support hw_scan, so use software
557 * scanning instead. First send a nullfunc frame with power save
558 * bit on so that AP will buffer the frames for us while we are not
559 * listening, then send probe requests to each channel and wait for
560 * the responses. After all channels are scanned, tune back to the
561 * original channel and send a nullfunc frame with power save bit
562 * off to trigger the AP to send us all the buffered frames.
563 *
564 * Note that while local->sw_scanning is true everything else but
565 * nullfunc frames and probe requests will be dropped in
566 * ieee80211_tx_h_check_assoc().
567 */
568 drv_sw_scan_start(local, sdata, local->scan_addr);
569
570 local->leave_oper_channel_time = jiffies;
571 local->next_scan_state = SCAN_DECISION;
572 local->scan_channel_idx = 0;
573
574 ieee80211_offchannel_stop_vifs(local);
575
576 /* ensure nullfunc is transmitted before leaving operating channel */
577 ieee80211_flush_queues(local, NULL, false);
578
579 ieee80211_configure_filter(local);
580
581 /* We need to set power level at maximum rate for scanning. */
582 ieee80211_hw_conf_chan(local);
583
584 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 0);
585
586 return 0;
587 }
588
__ieee80211_can_leave_ch(struct ieee80211_sub_if_data * sdata,struct cfg80211_scan_request * req)589 static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata,
590 struct cfg80211_scan_request *req)
591 {
592 struct ieee80211_local *local = sdata->local;
593 struct ieee80211_sub_if_data *sdata_iter;
594 unsigned int link_id;
595
596 lockdep_assert_wiphy(local->hw.wiphy);
597
598 if (!ieee80211_is_radar_required(local, req))
599 return true;
600
601 if (!regulatory_pre_cac_allowed(local->hw.wiphy))
602 return false;
603
604 list_for_each_entry(sdata_iter, &local->interfaces, list) {
605 for_each_valid_link(&sdata_iter->wdev, link_id)
606 if (sdata_iter->wdev.links[link_id].cac_started)
607 return false;
608 }
609
610 return true;
611 }
612
ieee80211_can_scan(struct ieee80211_local * local,struct ieee80211_sub_if_data * sdata,struct cfg80211_scan_request * req)613 static bool ieee80211_can_scan(struct ieee80211_local *local,
614 struct ieee80211_sub_if_data *sdata,
615 struct cfg80211_scan_request *req)
616 {
617 if (!__ieee80211_can_leave_ch(sdata, req))
618 return false;
619
620 if (!list_empty(&local->roc_list))
621 return false;
622
623 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
624 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL)
625 return false;
626
627 return true;
628 }
629
ieee80211_run_deferred_scan(struct ieee80211_local * local)630 void ieee80211_run_deferred_scan(struct ieee80211_local *local)
631 {
632 struct cfg80211_scan_request *req;
633
634 lockdep_assert_wiphy(local->hw.wiphy);
635
636 if (!local->scan_req || local->scanning)
637 return;
638
639 req = wiphy_dereference(local->hw.wiphy, local->scan_req);
640 if (!ieee80211_can_scan(local,
641 rcu_dereference_protected(
642 local->scan_sdata,
643 lockdep_is_held(&local->hw.wiphy->mtx)),
644 req))
645 return;
646
647 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work,
648 round_jiffies_relative(0));
649 }
650
ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data * sdata,const u8 * src,const u8 * dst,const u8 * ssid,size_t ssid_len,const u8 * ie,size_t ie_len,u32 ratemask,u32 flags,u32 tx_flags,struct ieee80211_channel * channel)651 static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata,
652 const u8 *src, const u8 *dst,
653 const u8 *ssid, size_t ssid_len,
654 const u8 *ie, size_t ie_len,
655 u32 ratemask, u32 flags, u32 tx_flags,
656 struct ieee80211_channel *channel)
657 {
658 struct sk_buff *skb;
659
660 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel,
661 ssid, ssid_len,
662 ie, ie_len, flags);
663
664 if (skb) {
665 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) {
666 struct ieee80211_hdr *hdr = (void *)skb->data;
667 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
668 u16 sn = get_random_u16();
669
670 info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO;
671 hdr->seq_ctrl =
672 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn));
673 }
674 IEEE80211_SKB_CB(skb)->flags |= tx_flags;
675 IEEE80211_SKB_CB(skb)->control.flags |= IEEE80211_TX_CTRL_DONT_USE_RATE_MASK;
676 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band);
677 }
678 }
679
ieee80211_scan_state_send_probe(struct ieee80211_local * local,unsigned long * next_delay)680 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
681 unsigned long *next_delay)
682 {
683 int i;
684 struct ieee80211_sub_if_data *sdata;
685 struct cfg80211_scan_request *scan_req;
686 enum nl80211_band band = local->hw.conf.chandef.chan->band;
687 u32 flags = 0, tx_flags;
688
689 scan_req = rcu_dereference_protected(local->scan_req,
690 lockdep_is_held(&local->hw.wiphy->mtx));
691
692 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
693 if (scan_req->no_cck)
694 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
695 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
696 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
697 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN)
698 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN;
699
700 sdata = rcu_dereference_protected(local->scan_sdata,
701 lockdep_is_held(&local->hw.wiphy->mtx));
702
703 for (i = 0; i < scan_req->n_ssids; i++)
704 ieee80211_send_scan_probe_req(
705 sdata, local->scan_addr, scan_req->bssid,
706 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len,
707 scan_req->ie, scan_req->ie_len,
708 scan_req->rates[band], flags,
709 tx_flags, local->hw.conf.chandef.chan);
710
711 /*
712 * After sending probe requests, wait for probe responses
713 * on the channel.
714 */
715 *next_delay = msecs_to_jiffies(scan_req->duration) >
716 IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME ?
717 msecs_to_jiffies(scan_req->duration) - IEEE80211_PROBE_DELAY :
718 IEEE80211_CHANNEL_TIME;
719 local->next_scan_state = SCAN_DECISION;
720 }
721
__ieee80211_start_scan(struct ieee80211_sub_if_data * sdata,struct cfg80211_scan_request * req)722 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
723 struct cfg80211_scan_request *req)
724 {
725 struct ieee80211_local *local = sdata->local;
726 bool hw_scan = local->ops->hw_scan;
727 int rc;
728
729 lockdep_assert_wiphy(local->hw.wiphy);
730
731 if (local->scan_req)
732 return -EBUSY;
733
734 /* For an MLO connection, if a link ID was specified, validate that it
735 * is indeed active.
736 */
737 if (ieee80211_vif_is_mld(&sdata->vif) && req->tsf_report_link_id >= 0 &&
738 !(sdata->vif.active_links & BIT(req->tsf_report_link_id)))
739 return -EINVAL;
740
741 if (!__ieee80211_can_leave_ch(sdata, req))
742 return -EBUSY;
743
744 if (!ieee80211_can_scan(local, sdata, req)) {
745 /* wait for the work to finish/time out */
746 rcu_assign_pointer(local->scan_req, req);
747 rcu_assign_pointer(local->scan_sdata, sdata);
748 return 0;
749 }
750
751 again:
752 if (hw_scan) {
753 u8 *ies;
754
755 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len;
756
757 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
758 int i, n_bands = 0;
759 u8 bands_counted = 0;
760
761 for (i = 0; i < req->n_channels; i++) {
762 if (bands_counted & BIT(req->channels[i]->band))
763 continue;
764 bands_counted |= BIT(req->channels[i]->band);
765 n_bands++;
766 }
767
768 local->hw_scan_ies_bufsize *= n_bands;
769 }
770
771 local->hw_scan_req = kmalloc(struct_size(local->hw_scan_req,
772 req.channels,
773 req->n_channels) +
774 local->hw_scan_ies_bufsize,
775 GFP_KERNEL);
776 if (!local->hw_scan_req)
777 return -ENOMEM;
778
779 local->hw_scan_req->req.ssids = req->ssids;
780 local->hw_scan_req->req.n_ssids = req->n_ssids;
781 /* None of the channels are actually set
782 * up but let UBSAN know the boundaries.
783 */
784 local->hw_scan_req->req.n_channels = req->n_channels;
785
786 ies = (u8 *)local->hw_scan_req +
787 sizeof(*local->hw_scan_req) +
788 req->n_channels * sizeof(req->channels[0]);
789 local->hw_scan_req->req.ie = ies;
790 local->hw_scan_req->req.flags = req->flags;
791 eth_broadcast_addr(local->hw_scan_req->req.bssid);
792 local->hw_scan_req->req.duration = req->duration;
793 local->hw_scan_req->req.duration_mandatory =
794 req->duration_mandatory;
795 local->hw_scan_req->req.tsf_report_link_id =
796 req->tsf_report_link_id;
797
798 local->hw_scan_band = 0;
799 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params;
800 local->hw_scan_req->req.scan_6ghz_params =
801 req->scan_6ghz_params;
802 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz;
803 local->hw_scan_req->req.first_part = req->first_part;
804
805 /*
806 * After allocating local->hw_scan_req, we must
807 * go through until ieee80211_prep_hw_scan(), so
808 * anything that might be changed here and leave
809 * this function early must not go after this
810 * allocation.
811 */
812 }
813
814 rcu_assign_pointer(local->scan_req, req);
815 rcu_assign_pointer(local->scan_sdata, sdata);
816
817 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
818 get_random_mask_addr(local->scan_addr,
819 req->mac_addr,
820 req->mac_addr_mask);
821 else
822 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN);
823
824 if (hw_scan) {
825 __set_bit(SCAN_HW_SCANNING, &local->scanning);
826 } else if ((req->n_channels == 1) &&
827 (req->channels[0] == local->hw.conf.chandef.chan)) {
828 /*
829 * If we are scanning only on the operating channel
830 * then we do not need to stop normal activities
831 */
832 unsigned long next_delay;
833
834 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
835
836 ieee80211_recalc_idle(local);
837
838 /* Notify driver scan is starting, keep order of operations
839 * same as normal software scan, in case that matters. */
840 drv_sw_scan_start(local, sdata, local->scan_addr);
841
842 ieee80211_configure_filter(local); /* accept probe-responses */
843
844 /* We need to ensure power level is at max for scanning. */
845 ieee80211_hw_conf_chan(local);
846
847 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR |
848 IEEE80211_CHAN_RADAR)) ||
849 !req->n_ssids) {
850 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
851 if (req->n_ssids)
852 set_bit(SCAN_BEACON_WAIT, &local->scanning);
853 } else {
854 ieee80211_scan_state_send_probe(local, &next_delay);
855 next_delay = IEEE80211_CHANNEL_TIME;
856 }
857
858 /* Now, just wait a bit and we are all done! */
859 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work,
860 next_delay);
861 return 0;
862 } else {
863 /* Do normal software scan */
864 __set_bit(SCAN_SW_SCANNING, &local->scanning);
865 }
866
867 ieee80211_recalc_idle(local);
868
869 if (hw_scan) {
870 WARN_ON(!ieee80211_prep_hw_scan(sdata));
871 rc = drv_hw_scan(local, sdata, local->hw_scan_req);
872 } else {
873 rc = ieee80211_start_sw_scan(local, sdata);
874 }
875
876 if (rc) {
877 kfree(local->hw_scan_req);
878 local->hw_scan_req = NULL;
879 local->scanning = 0;
880
881 ieee80211_recalc_idle(local);
882
883 local->scan_req = NULL;
884 RCU_INIT_POINTER(local->scan_sdata, NULL);
885 }
886
887 if (hw_scan && rc == 1) {
888 /*
889 * we can't fall back to software for P2P-GO
890 * as it must update NoA etc.
891 */
892 if (ieee80211_vif_type_p2p(&sdata->vif) ==
893 NL80211_IFTYPE_P2P_GO)
894 return -EOPNOTSUPP;
895 hw_scan = false;
896 goto again;
897 }
898
899 return rc;
900 }
901
902 static unsigned long
ieee80211_scan_get_channel_time(struct ieee80211_channel * chan)903 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
904 {
905 /*
906 * TODO: channel switching also consumes quite some time,
907 * add that delay as well to get a better estimation
908 */
909 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR))
910 return IEEE80211_PASSIVE_CHANNEL_TIME;
911 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
912 }
913
ieee80211_scan_state_decision(struct ieee80211_local * local,unsigned long * next_delay)914 static void ieee80211_scan_state_decision(struct ieee80211_local *local,
915 unsigned long *next_delay)
916 {
917 bool associated = false;
918 bool tx_empty = true;
919 bool bad_latency;
920 struct ieee80211_sub_if_data *sdata;
921 struct ieee80211_channel *next_chan;
922 enum mac80211_scan_state next_scan_state;
923 struct cfg80211_scan_request *scan_req;
924
925 lockdep_assert_wiphy(local->hw.wiphy);
926
927 /*
928 * check if at least one STA interface is associated,
929 * check if at least one STA interface has pending tx frames
930 * and grab the lowest used beacon interval
931 */
932 list_for_each_entry(sdata, &local->interfaces, list) {
933 if (!ieee80211_sdata_running(sdata))
934 continue;
935
936 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
937 if (sdata->u.mgd.associated) {
938 associated = true;
939
940 if (!qdisc_all_tx_empty(sdata->dev)) {
941 tx_empty = false;
942 break;
943 }
944 }
945 }
946 }
947
948 scan_req = rcu_dereference_protected(local->scan_req,
949 lockdep_is_held(&local->hw.wiphy->mtx));
950
951 next_chan = scan_req->channels[local->scan_channel_idx];
952
953 /*
954 * we're currently scanning a different channel, let's
955 * see if we can scan another channel without interfering
956 * with the current traffic situation.
957 *
958 * Keep good latency, do not stay off-channel more than 125 ms.
959 */
960
961 bad_latency = time_after(jiffies +
962 ieee80211_scan_get_channel_time(next_chan),
963 local->leave_oper_channel_time + HZ / 8);
964
965 if (associated && !tx_empty) {
966 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY)
967 next_scan_state = SCAN_ABORT;
968 else
969 next_scan_state = SCAN_SUSPEND;
970 } else if (associated && bad_latency) {
971 next_scan_state = SCAN_SUSPEND;
972 } else {
973 next_scan_state = SCAN_SET_CHANNEL;
974 }
975
976 local->next_scan_state = next_scan_state;
977
978 *next_delay = 0;
979 }
980
ieee80211_scan_state_set_channel(struct ieee80211_local * local,unsigned long * next_delay)981 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
982 unsigned long *next_delay)
983 {
984 int skip;
985 struct ieee80211_channel *chan;
986 struct cfg80211_scan_request *scan_req;
987
988 scan_req = rcu_dereference_protected(local->scan_req,
989 lockdep_is_held(&local->hw.wiphy->mtx));
990
991 skip = 0;
992 chan = scan_req->channels[local->scan_channel_idx];
993
994 local->scan_chandef.chan = chan;
995 local->scan_chandef.center_freq1 = chan->center_freq;
996 local->scan_chandef.freq1_offset = chan->freq_offset;
997 local->scan_chandef.center_freq2 = 0;
998
999 /* For scanning on the S1G band, detect the channel width according to
1000 * the channel being scanned.
1001 */
1002 if (chan->band == NL80211_BAND_S1GHZ) {
1003 local->scan_chandef.width = ieee80211_s1g_channel_width(chan);
1004 goto set_channel;
1005 }
1006
1007 /* If scanning on oper channel, use whatever channel-type
1008 * is currently in use.
1009 */
1010 if (chan == local->hw.conf.chandef.chan)
1011 local->scan_chandef = local->hw.conf.chandef;
1012 else
1013 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
1014
1015 set_channel:
1016 if (ieee80211_hw_conf_chan(local))
1017 skip = 1;
1018
1019 /* advance state machine to next channel/band */
1020 local->scan_channel_idx++;
1021
1022 if (skip) {
1023 /* if we skip this channel return to the decision state */
1024 local->next_scan_state = SCAN_DECISION;
1025 return;
1026 }
1027
1028 /*
1029 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
1030 * (which unfortunately doesn't say _why_ step a) is done,
1031 * but it waits for the probe delay or until a frame is
1032 * received - and the received frame would update the NAV).
1033 * For now, we do not support waiting until a frame is
1034 * received.
1035 *
1036 * In any case, it is not necessary for a passive scan.
1037 */
1038 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) ||
1039 !scan_req->n_ssids) {
1040 *next_delay = max(msecs_to_jiffies(scan_req->duration),
1041 IEEE80211_PASSIVE_CHANNEL_TIME);
1042 local->next_scan_state = SCAN_DECISION;
1043 if (scan_req->n_ssids)
1044 set_bit(SCAN_BEACON_WAIT, &local->scanning);
1045 return;
1046 }
1047
1048 /* active scan, send probes */
1049 *next_delay = IEEE80211_PROBE_DELAY;
1050 local->next_scan_state = SCAN_SEND_PROBE;
1051 }
1052
ieee80211_scan_state_suspend(struct ieee80211_local * local,unsigned long * next_delay)1053 static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
1054 unsigned long *next_delay)
1055 {
1056 /* switch back to the operating channel */
1057 local->scan_chandef.chan = NULL;
1058 ieee80211_hw_conf_chan(local);
1059
1060 /* disable PS */
1061 ieee80211_offchannel_return(local);
1062
1063 *next_delay = HZ / 5;
1064 /* afterwards, resume scan & go to next channel */
1065 local->next_scan_state = SCAN_RESUME;
1066 }
1067
ieee80211_scan_state_resume(struct ieee80211_local * local,unsigned long * next_delay)1068 static void ieee80211_scan_state_resume(struct ieee80211_local *local,
1069 unsigned long *next_delay)
1070 {
1071 ieee80211_offchannel_stop_vifs(local);
1072
1073 if (local->ops->flush) {
1074 ieee80211_flush_queues(local, NULL, false);
1075 *next_delay = 0;
1076 } else
1077 *next_delay = HZ / 10;
1078
1079 /* remember when we left the operating channel */
1080 local->leave_oper_channel_time = jiffies;
1081
1082 /* advance to the next channel to be scanned */
1083 local->next_scan_state = SCAN_SET_CHANNEL;
1084 }
1085
ieee80211_scan_work(struct wiphy * wiphy,struct wiphy_work * work)1086 void ieee80211_scan_work(struct wiphy *wiphy, struct wiphy_work *work)
1087 {
1088 struct ieee80211_local *local =
1089 container_of(work, struct ieee80211_local, scan_work.work);
1090 struct ieee80211_sub_if_data *sdata;
1091 struct cfg80211_scan_request *scan_req;
1092 unsigned long next_delay = 0;
1093 bool aborted;
1094
1095 lockdep_assert_wiphy(local->hw.wiphy);
1096
1097 if (!ieee80211_can_run_worker(local)) {
1098 aborted = true;
1099 goto out_complete;
1100 }
1101
1102 sdata = rcu_dereference_protected(local->scan_sdata,
1103 lockdep_is_held(&local->hw.wiphy->mtx));
1104 scan_req = rcu_dereference_protected(local->scan_req,
1105 lockdep_is_held(&local->hw.wiphy->mtx));
1106
1107 /* When scanning on-channel, the first-callback means completed. */
1108 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) {
1109 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
1110 goto out_complete;
1111 }
1112
1113 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) {
1114 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
1115 goto out_complete;
1116 }
1117
1118 if (!sdata || !scan_req)
1119 return;
1120
1121 if (!local->scanning) {
1122 int rc;
1123
1124 RCU_INIT_POINTER(local->scan_req, NULL);
1125 RCU_INIT_POINTER(local->scan_sdata, NULL);
1126
1127 rc = __ieee80211_start_scan(sdata, scan_req);
1128 if (!rc)
1129 return;
1130 /* need to complete scan in cfg80211 */
1131 rcu_assign_pointer(local->scan_req, scan_req);
1132 aborted = true;
1133 goto out_complete;
1134 }
1135
1136 clear_bit(SCAN_BEACON_WAIT, &local->scanning);
1137
1138 /*
1139 * as long as no delay is required advance immediately
1140 * without scheduling a new work
1141 */
1142 do {
1143 if (!ieee80211_sdata_running(sdata)) {
1144 aborted = true;
1145 goto out_complete;
1146 }
1147
1148 if (test_and_clear_bit(SCAN_BEACON_DONE, &local->scanning) &&
1149 local->next_scan_state == SCAN_DECISION)
1150 local->next_scan_state = SCAN_SEND_PROBE;
1151
1152 switch (local->next_scan_state) {
1153 case SCAN_DECISION:
1154 /* if no more bands/channels left, complete scan */
1155 if (local->scan_channel_idx >= scan_req->n_channels) {
1156 aborted = false;
1157 goto out_complete;
1158 }
1159 ieee80211_scan_state_decision(local, &next_delay);
1160 break;
1161 case SCAN_SET_CHANNEL:
1162 ieee80211_scan_state_set_channel(local, &next_delay);
1163 break;
1164 case SCAN_SEND_PROBE:
1165 ieee80211_scan_state_send_probe(local, &next_delay);
1166 break;
1167 case SCAN_SUSPEND:
1168 ieee80211_scan_state_suspend(local, &next_delay);
1169 break;
1170 case SCAN_RESUME:
1171 ieee80211_scan_state_resume(local, &next_delay);
1172 break;
1173 case SCAN_ABORT:
1174 aborted = true;
1175 goto out_complete;
1176 }
1177 } while (next_delay == 0);
1178
1179 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work,
1180 next_delay);
1181 return;
1182
1183 out_complete:
1184 __ieee80211_scan_completed(&local->hw, aborted);
1185 }
1186
ieee80211_request_scan(struct ieee80211_sub_if_data * sdata,struct cfg80211_scan_request * req)1187 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
1188 struct cfg80211_scan_request *req)
1189 {
1190 lockdep_assert_wiphy(sdata->local->hw.wiphy);
1191
1192 return __ieee80211_start_scan(sdata, req);
1193 }
1194
ieee80211_request_ibss_scan(struct ieee80211_sub_if_data * sdata,const u8 * ssid,u8 ssid_len,struct ieee80211_channel ** channels,unsigned int n_channels)1195 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
1196 const u8 *ssid, u8 ssid_len,
1197 struct ieee80211_channel **channels,
1198 unsigned int n_channels)
1199 {
1200 struct ieee80211_local *local = sdata->local;
1201 int i, n_ch = 0;
1202 enum nl80211_band band;
1203
1204 lockdep_assert_wiphy(local->hw.wiphy);
1205
1206 /* busy scanning */
1207 if (local->scan_req)
1208 return -EBUSY;
1209
1210 /* fill internal scan request */
1211 if (!channels) {
1212 int max_n;
1213
1214 for (band = 0; band < NUM_NL80211_BANDS; band++) {
1215 if (!local->hw.wiphy->bands[band] ||
1216 band == NL80211_BAND_6GHZ)
1217 continue;
1218
1219 max_n = local->hw.wiphy->bands[band]->n_channels;
1220 for (i = 0; i < max_n; i++) {
1221 struct ieee80211_channel *tmp_ch =
1222 &local->hw.wiphy->bands[band]->channels[i];
1223
1224 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR |
1225 IEEE80211_CHAN_DISABLED) ||
1226 !cfg80211_wdev_channel_allowed(&sdata->wdev,
1227 tmp_ch))
1228 continue;
1229
1230 local->int_scan_req->channels[n_ch] = tmp_ch;
1231 n_ch++;
1232 }
1233 }
1234
1235 if (WARN_ON_ONCE(n_ch == 0))
1236 return -EINVAL;
1237
1238 local->int_scan_req->n_channels = n_ch;
1239 } else {
1240 for (i = 0; i < n_channels; i++) {
1241 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR |
1242 IEEE80211_CHAN_DISABLED) ||
1243 !cfg80211_wdev_channel_allowed(&sdata->wdev,
1244 channels[i]))
1245 continue;
1246
1247 local->int_scan_req->channels[n_ch] = channels[i];
1248 n_ch++;
1249 }
1250
1251 if (n_ch == 0)
1252 return -EINVAL;
1253
1254 local->int_scan_req->n_channels = n_ch;
1255 }
1256
1257 local->int_scan_req->ssids = &local->scan_ssid;
1258 local->int_scan_req->n_ssids = 1;
1259 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
1260 local->int_scan_req->ssids[0].ssid_len = ssid_len;
1261
1262 return __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
1263 }
1264
ieee80211_scan_cancel(struct ieee80211_local * local)1265 void ieee80211_scan_cancel(struct ieee80211_local *local)
1266 {
1267 /* ensure a new scan cannot be queued */
1268 lockdep_assert_wiphy(local->hw.wiphy);
1269
1270 /*
1271 * We are canceling software scan, or deferred scan that was not
1272 * yet really started (see __ieee80211_start_scan ).
1273 *
1274 * Regarding hardware scan:
1275 * - we can not call __ieee80211_scan_completed() as when
1276 * SCAN_HW_SCANNING bit is set this function change
1277 * local->hw_scan_req to operate on 5G band, what race with
1278 * driver which can use local->hw_scan_req
1279 *
1280 * - we can not cancel scan_work since driver can schedule it
1281 * by ieee80211_scan_completed(..., true) to finish scan
1282 *
1283 * Hence we only call the cancel_hw_scan() callback, but the low-level
1284 * driver is still responsible for calling ieee80211_scan_completed()
1285 * after the scan was completed/aborted.
1286 */
1287
1288 if (!local->scan_req)
1289 return;
1290
1291 /*
1292 * We have a scan running and the driver already reported completion,
1293 * but the worker hasn't run yet or is stuck on the mutex - mark it as
1294 * cancelled.
1295 */
1296 if (test_bit(SCAN_HW_SCANNING, &local->scanning) &&
1297 test_bit(SCAN_COMPLETED, &local->scanning)) {
1298 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1299 return;
1300 }
1301
1302 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
1303 /*
1304 * Make sure that __ieee80211_scan_completed doesn't trigger a
1305 * scan on another band.
1306 */
1307 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1308 if (local->ops->cancel_hw_scan)
1309 drv_cancel_hw_scan(local,
1310 rcu_dereference_protected(local->scan_sdata,
1311 lockdep_is_held(&local->hw.wiphy->mtx)));
1312 return;
1313 }
1314
1315 wiphy_delayed_work_cancel(local->hw.wiphy, &local->scan_work);
1316 /* and clean up */
1317 memset(&local->scan_info, 0, sizeof(local->scan_info));
1318 __ieee80211_scan_completed(&local->hw, true);
1319 }
1320
__ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data * sdata,struct cfg80211_sched_scan_request * req)1321 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1322 struct cfg80211_sched_scan_request *req)
1323 {
1324 struct ieee80211_local *local = sdata->local;
1325 struct ieee80211_scan_ies sched_scan_ies = {};
1326 struct cfg80211_chan_def chandef;
1327 int ret, i, iebufsz, num_bands = 0;
1328 u32 rate_masks[NUM_NL80211_BANDS] = {};
1329 u8 bands_used = 0;
1330 u8 *ie;
1331 u32 flags = 0;
1332
1333 lockdep_assert_wiphy(local->hw.wiphy);
1334
1335 iebufsz = local->scan_ies_len + req->ie_len;
1336
1337 if (!local->ops->sched_scan_start)
1338 return -EOPNOTSUPP;
1339
1340 for (i = 0; i < NUM_NL80211_BANDS; i++) {
1341 if (local->hw.wiphy->bands[i]) {
1342 bands_used |= BIT(i);
1343 rate_masks[i] = (u32) -1;
1344 num_bands++;
1345 }
1346 }
1347
1348 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
1349 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
1350
1351 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL);
1352 if (!ie) {
1353 ret = -ENOMEM;
1354 goto out;
1355 }
1356
1357 ieee80211_prepare_scan_chandef(&chandef);
1358
1359 ret = ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz,
1360 &sched_scan_ies, req->ie,
1361 req->ie_len, bands_used, rate_masks,
1362 &chandef, flags);
1363 if (ret < 0)
1364 goto error;
1365
1366 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
1367 if (ret == 0) {
1368 rcu_assign_pointer(local->sched_scan_sdata, sdata);
1369 rcu_assign_pointer(local->sched_scan_req, req);
1370 }
1371
1372 error:
1373 kfree(ie);
1374 out:
1375 if (ret) {
1376 /* Clean in case of failure after HW restart or upon resume. */
1377 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1378 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1379 }
1380
1381 return ret;
1382 }
1383
ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data * sdata,struct cfg80211_sched_scan_request * req)1384 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1385 struct cfg80211_sched_scan_request *req)
1386 {
1387 struct ieee80211_local *local = sdata->local;
1388
1389 lockdep_assert_wiphy(local->hw.wiphy);
1390
1391 if (rcu_access_pointer(local->sched_scan_sdata))
1392 return -EBUSY;
1393
1394 return __ieee80211_request_sched_scan_start(sdata, req);
1395 }
1396
ieee80211_request_sched_scan_stop(struct ieee80211_local * local)1397 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local)
1398 {
1399 struct ieee80211_sub_if_data *sched_scan_sdata;
1400 int ret = -ENOENT;
1401
1402 lockdep_assert_wiphy(local->hw.wiphy);
1403
1404 if (!local->ops->sched_scan_stop)
1405 return -EOPNOTSUPP;
1406
1407 /* We don't want to restart sched scan anymore. */
1408 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1409
1410 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata,
1411 lockdep_is_held(&local->hw.wiphy->mtx));
1412 if (sched_scan_sdata) {
1413 ret = drv_sched_scan_stop(local, sched_scan_sdata);
1414 if (!ret)
1415 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1416 }
1417
1418 return ret;
1419 }
1420
ieee80211_sched_scan_results(struct ieee80211_hw * hw)1421 void 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 }
1429 EXPORT_SYMBOL(ieee80211_sched_scan_results);
1430
ieee80211_sched_scan_end(struct ieee80211_local * local)1431 void ieee80211_sched_scan_end(struct ieee80211_local *local)
1432 {
1433 lockdep_assert_wiphy(local->hw.wiphy);
1434
1435 if (!rcu_access_pointer(local->sched_scan_sdata))
1436 return;
1437
1438 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1439
1440 /* If sched scan was aborted by the driver. */
1441 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1442
1443 cfg80211_sched_scan_stopped_locked(local->hw.wiphy, 0);
1444 }
1445
ieee80211_sched_scan_stopped_work(struct wiphy * wiphy,struct wiphy_work * work)1446 void ieee80211_sched_scan_stopped_work(struct wiphy *wiphy,
1447 struct wiphy_work *work)
1448 {
1449 struct ieee80211_local *local =
1450 container_of(work, struct ieee80211_local,
1451 sched_scan_stopped_work);
1452
1453 ieee80211_sched_scan_end(local);
1454 }
1455
ieee80211_sched_scan_stopped(struct ieee80211_hw * hw)1456 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
1457 {
1458 struct ieee80211_local *local = hw_to_local(hw);
1459
1460 trace_api_sched_scan_stopped(local);
1461
1462 /*
1463 * this shouldn't really happen, so for simplicity
1464 * simply ignore it, and let mac80211 reconfigure
1465 * the sched scan later on.
1466 */
1467 if (local->in_reconfig)
1468 return;
1469
1470 wiphy_work_queue(hw->wiphy, &local->sched_scan_stopped_work);
1471 }
1472 EXPORT_SYMBOL(ieee80211_sched_scan_stopped);
1473