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
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 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
ieee80211_scan_rx(struct ieee80211_local * local,struct sk_buff * skb)257 void 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
ieee80211_prepare_scan_chandef(struct cfg80211_chan_def * chandef)347 static 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 */
ieee80211_prep_hw_scan(struct ieee80211_sub_if_data * sdata)355 static 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
__ieee80211_scan_completed(struct ieee80211_hw * hw,bool aborted)424 static 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
ieee80211_scan_completed(struct ieee80211_hw * hw,struct cfg80211_scan_info * info)516 void 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 }
531 EXPORT_SYMBOL(ieee80211_scan_completed);
532
ieee80211_start_sw_scan(struct ieee80211_local * local,struct ieee80211_sub_if_data * sdata)533 static 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
__ieee80211_can_leave_ch(struct ieee80211_sub_if_data * sdata)574 static 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
ieee80211_can_scan(struct ieee80211_local * local,struct ieee80211_sub_if_data * sdata)597 static 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
ieee80211_run_deferred_scan(struct ieee80211_local * local)613 void 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
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)630 static 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
ieee80211_scan_state_send_probe(struct ieee80211_local * local,unsigned long * next_delay)659 static 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
__ieee80211_start_scan(struct ieee80211_sub_if_data * sdata,struct cfg80211_scan_request * req)701 static 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
880 static unsigned long
ieee80211_scan_get_channel_time(struct ieee80211_channel * chan)881 ieee80211_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
ieee80211_scan_state_decision(struct ieee80211_local * local,unsigned long * next_delay)892 static 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
ieee80211_scan_state_set_channel(struct ieee80211_local * local,unsigned long * next_delay)959 static 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
993 set_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
ieee80211_scan_state_suspend(struct ieee80211_local * local,unsigned long * next_delay)1031 static 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
ieee80211_scan_state_resume(struct ieee80211_local * local,unsigned long * next_delay)1046 static 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
ieee80211_scan_work(struct wiphy * wiphy,struct wiphy_work * work)1064 void 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
1161 out_complete:
1162 __ieee80211_scan_completed(&local->hw, aborted);
1163 }
1164
ieee80211_request_scan(struct ieee80211_sub_if_data * sdata,struct cfg80211_scan_request * req)1165 int 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
ieee80211_request_ibss_scan(struct ieee80211_sub_if_data * sdata,const u8 * ssid,u8 ssid_len,struct ieee80211_channel ** channels,unsigned int n_channels)1173 int 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 ret = -EBUSY, 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 goto unlock;
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 continue;
1205
1206 local->int_scan_req->channels[n_ch] = tmp_ch;
1207 n_ch++;
1208 }
1209 }
1210
1211 if (WARN_ON_ONCE(n_ch == 0))
1212 goto unlock;
1213
1214 local->int_scan_req->n_channels = n_ch;
1215 } else {
1216 for (i = 0; i < n_channels; i++) {
1217 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR |
1218 IEEE80211_CHAN_DISABLED))
1219 continue;
1220
1221 local->int_scan_req->channels[n_ch] = channels[i];
1222 n_ch++;
1223 }
1224
1225 if (WARN_ON_ONCE(n_ch == 0))
1226 goto unlock;
1227
1228 local->int_scan_req->n_channels = n_ch;
1229 }
1230
1231 local->int_scan_req->ssids = &local->scan_ssid;
1232 local->int_scan_req->n_ssids = 1;
1233 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
1234 local->int_scan_req->ssids[0].ssid_len = ssid_len;
1235
1236 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
1237 unlock:
1238 return ret;
1239 }
1240
ieee80211_scan_cancel(struct ieee80211_local * local)1241 void ieee80211_scan_cancel(struct ieee80211_local *local)
1242 {
1243 /* ensure a new scan cannot be queued */
1244 lockdep_assert_wiphy(local->hw.wiphy);
1245
1246 /*
1247 * We are canceling software scan, or deferred scan that was not
1248 * yet really started (see __ieee80211_start_scan ).
1249 *
1250 * Regarding hardware scan:
1251 * - we can not call __ieee80211_scan_completed() as when
1252 * SCAN_HW_SCANNING bit is set this function change
1253 * local->hw_scan_req to operate on 5G band, what race with
1254 * driver which can use local->hw_scan_req
1255 *
1256 * - we can not cancel scan_work since driver can schedule it
1257 * by ieee80211_scan_completed(..., true) to finish scan
1258 *
1259 * Hence we only call the cancel_hw_scan() callback, but the low-level
1260 * driver is still responsible for calling ieee80211_scan_completed()
1261 * after the scan was completed/aborted.
1262 */
1263
1264 if (!local->scan_req)
1265 return;
1266
1267 /*
1268 * We have a scan running and the driver already reported completion,
1269 * but the worker hasn't run yet or is stuck on the mutex - mark it as
1270 * cancelled.
1271 */
1272 if (test_bit(SCAN_HW_SCANNING, &local->scanning) &&
1273 test_bit(SCAN_COMPLETED, &local->scanning)) {
1274 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1275 return;
1276 }
1277
1278 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
1279 /*
1280 * Make sure that __ieee80211_scan_completed doesn't trigger a
1281 * scan on another band.
1282 */
1283 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1284 if (local->ops->cancel_hw_scan)
1285 drv_cancel_hw_scan(local,
1286 rcu_dereference_protected(local->scan_sdata,
1287 lockdep_is_held(&local->hw.wiphy->mtx)));
1288 return;
1289 }
1290
1291 wiphy_delayed_work_cancel(local->hw.wiphy, &local->scan_work);
1292 /* and clean up */
1293 memset(&local->scan_info, 0, sizeof(local->scan_info));
1294 __ieee80211_scan_completed(&local->hw, true);
1295 }
1296
__ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data * sdata,struct cfg80211_sched_scan_request * req)1297 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1298 struct cfg80211_sched_scan_request *req)
1299 {
1300 struct ieee80211_local *local = sdata->local;
1301 struct ieee80211_scan_ies sched_scan_ies = {};
1302 struct cfg80211_chan_def chandef;
1303 int ret, i, iebufsz, num_bands = 0;
1304 u32 rate_masks[NUM_NL80211_BANDS] = {};
1305 u8 bands_used = 0;
1306 u8 *ie;
1307 u32 flags = 0;
1308
1309 lockdep_assert_wiphy(local->hw.wiphy);
1310
1311 iebufsz = local->scan_ies_len + req->ie_len;
1312
1313 if (!local->ops->sched_scan_start)
1314 return -EOPNOTSUPP;
1315
1316 for (i = 0; i < NUM_NL80211_BANDS; i++) {
1317 if (local->hw.wiphy->bands[i]) {
1318 bands_used |= BIT(i);
1319 rate_masks[i] = (u32) -1;
1320 num_bands++;
1321 }
1322 }
1323
1324 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
1325 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
1326
1327 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL);
1328 if (!ie) {
1329 ret = -ENOMEM;
1330 goto out;
1331 }
1332
1333 ieee80211_prepare_scan_chandef(&chandef);
1334
1335 ret = ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz,
1336 &sched_scan_ies, req->ie,
1337 req->ie_len, bands_used, rate_masks,
1338 &chandef, flags);
1339 if (ret < 0)
1340 goto error;
1341
1342 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
1343 if (ret == 0) {
1344 rcu_assign_pointer(local->sched_scan_sdata, sdata);
1345 rcu_assign_pointer(local->sched_scan_req, req);
1346 }
1347
1348 error:
1349 kfree(ie);
1350 out:
1351 if (ret) {
1352 /* Clean in case of failure after HW restart or upon resume. */
1353 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1354 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1355 }
1356
1357 return ret;
1358 }
1359
ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data * sdata,struct cfg80211_sched_scan_request * req)1360 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1361 struct cfg80211_sched_scan_request *req)
1362 {
1363 struct ieee80211_local *local = sdata->local;
1364
1365 lockdep_assert_wiphy(local->hw.wiphy);
1366
1367 if (rcu_access_pointer(local->sched_scan_sdata))
1368 return -EBUSY;
1369
1370 return __ieee80211_request_sched_scan_start(sdata, req);
1371 }
1372
ieee80211_request_sched_scan_stop(struct ieee80211_local * local)1373 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local)
1374 {
1375 struct ieee80211_sub_if_data *sched_scan_sdata;
1376 int ret = -ENOENT;
1377
1378 lockdep_assert_wiphy(local->hw.wiphy);
1379
1380 if (!local->ops->sched_scan_stop)
1381 return -EOPNOTSUPP;
1382
1383 /* We don't want to restart sched scan anymore. */
1384 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1385
1386 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata,
1387 lockdep_is_held(&local->hw.wiphy->mtx));
1388 if (sched_scan_sdata) {
1389 ret = drv_sched_scan_stop(local, sched_scan_sdata);
1390 if (!ret)
1391 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1392 }
1393
1394 return ret;
1395 }
1396
ieee80211_sched_scan_results(struct ieee80211_hw * hw)1397 void ieee80211_sched_scan_results(struct ieee80211_hw *hw)
1398 {
1399 struct ieee80211_local *local = hw_to_local(hw);
1400
1401 trace_api_sched_scan_results(local);
1402
1403 cfg80211_sched_scan_results(hw->wiphy, 0);
1404 }
1405 EXPORT_SYMBOL(ieee80211_sched_scan_results);
1406
ieee80211_sched_scan_end(struct ieee80211_local * local)1407 void ieee80211_sched_scan_end(struct ieee80211_local *local)
1408 {
1409 lockdep_assert_wiphy(local->hw.wiphy);
1410
1411 if (!rcu_access_pointer(local->sched_scan_sdata))
1412 return;
1413
1414 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1415
1416 /* If sched scan was aborted by the driver. */
1417 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1418
1419 cfg80211_sched_scan_stopped_locked(local->hw.wiphy, 0);
1420 }
1421
ieee80211_sched_scan_stopped_work(struct wiphy * wiphy,struct wiphy_work * work)1422 void ieee80211_sched_scan_stopped_work(struct wiphy *wiphy,
1423 struct wiphy_work *work)
1424 {
1425 struct ieee80211_local *local =
1426 container_of(work, struct ieee80211_local,
1427 sched_scan_stopped_work);
1428
1429 ieee80211_sched_scan_end(local);
1430 }
1431
ieee80211_sched_scan_stopped(struct ieee80211_hw * hw)1432 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
1433 {
1434 struct ieee80211_local *local = hw_to_local(hw);
1435
1436 trace_api_sched_scan_stopped(local);
1437
1438 /*
1439 * this shouldn't really happen, so for simplicity
1440 * simply ignore it, and let mac80211 reconfigure
1441 * the sched scan later on.
1442 */
1443 if (local->in_reconfig)
1444 return;
1445
1446 wiphy_work_queue(hw->wiphy, &local->sched_scan_stopped_work);
1447 }
1448 EXPORT_SYMBOL(ieee80211_sched_scan_stopped);
1449