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 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)589 static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata)
590 {
591 struct ieee80211_local *local = sdata->local;
592 struct ieee80211_sub_if_data *sdata_iter;
593 unsigned int link_id;
594
595 lockdep_assert_wiphy(local->hw.wiphy);
596
597 if (!ieee80211_is_radar_required(local))
598 return true;
599
600 if (!regulatory_pre_cac_allowed(local->hw.wiphy))
601 return false;
602
603 list_for_each_entry(sdata_iter, &local->interfaces, list) {
604 for_each_valid_link(&sdata_iter->wdev, link_id)
605 if (sdata_iter->wdev.links[link_id].cac_started)
606 return false;
607 }
608
609 return true;
610 }
611
ieee80211_can_scan(struct ieee80211_local * local,struct ieee80211_sub_if_data * sdata)612 static bool ieee80211_can_scan(struct ieee80211_local *local,
613 struct ieee80211_sub_if_data *sdata)
614 {
615 if (!__ieee80211_can_leave_ch(sdata))
616 return false;
617
618 if (!list_empty(&local->roc_list))
619 return false;
620
621 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
622 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL)
623 return false;
624
625 return true;
626 }
627
ieee80211_run_deferred_scan(struct ieee80211_local * local)628 void ieee80211_run_deferred_scan(struct ieee80211_local *local)
629 {
630 lockdep_assert_wiphy(local->hw.wiphy);
631
632 if (!local->scan_req || local->scanning)
633 return;
634
635 if (!ieee80211_can_scan(local,
636 rcu_dereference_protected(
637 local->scan_sdata,
638 lockdep_is_held(&local->hw.wiphy->mtx))))
639 return;
640
641 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work,
642 round_jiffies_relative(0));
643 }
644
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)645 static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata,
646 const u8 *src, const u8 *dst,
647 const u8 *ssid, size_t ssid_len,
648 const u8 *ie, size_t ie_len,
649 u32 ratemask, u32 flags, u32 tx_flags,
650 struct ieee80211_channel *channel)
651 {
652 struct sk_buff *skb;
653
654 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel,
655 ssid, ssid_len,
656 ie, ie_len, flags);
657
658 if (skb) {
659 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) {
660 struct ieee80211_hdr *hdr = (void *)skb->data;
661 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
662 u16 sn = get_random_u16();
663
664 info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO;
665 hdr->seq_ctrl =
666 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn));
667 }
668 IEEE80211_SKB_CB(skb)->flags |= tx_flags;
669 IEEE80211_SKB_CB(skb)->control.flags |= IEEE80211_TX_CTRL_DONT_USE_RATE_MASK;
670 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band);
671 }
672 }
673
ieee80211_scan_state_send_probe(struct ieee80211_local * local,unsigned long * next_delay)674 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
675 unsigned long *next_delay)
676 {
677 int i;
678 struct ieee80211_sub_if_data *sdata;
679 struct cfg80211_scan_request *scan_req;
680 enum nl80211_band band = local->hw.conf.chandef.chan->band;
681 u32 flags = 0, tx_flags;
682
683 scan_req = rcu_dereference_protected(local->scan_req,
684 lockdep_is_held(&local->hw.wiphy->mtx));
685
686 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
687 if (scan_req->no_cck)
688 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
689 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
690 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
691 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN)
692 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN;
693
694 sdata = rcu_dereference_protected(local->scan_sdata,
695 lockdep_is_held(&local->hw.wiphy->mtx));
696
697 for (i = 0; i < scan_req->n_ssids; i++)
698 ieee80211_send_scan_probe_req(
699 sdata, local->scan_addr, scan_req->bssid,
700 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len,
701 scan_req->ie, scan_req->ie_len,
702 scan_req->rates[band], flags,
703 tx_flags, local->hw.conf.chandef.chan);
704
705 /*
706 * After sending probe requests, wait for probe responses
707 * on the channel.
708 */
709 *next_delay = msecs_to_jiffies(scan_req->duration) >
710 IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME ?
711 msecs_to_jiffies(scan_req->duration) - IEEE80211_PROBE_DELAY :
712 IEEE80211_CHANNEL_TIME;
713 local->next_scan_state = SCAN_DECISION;
714 }
715
__ieee80211_start_scan(struct ieee80211_sub_if_data * sdata,struct cfg80211_scan_request * req)716 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
717 struct cfg80211_scan_request *req)
718 {
719 struct ieee80211_local *local = sdata->local;
720 bool hw_scan = local->ops->hw_scan;
721 int rc;
722
723 lockdep_assert_wiphy(local->hw.wiphy);
724
725 if (local->scan_req)
726 return -EBUSY;
727
728 /* For an MLO connection, if a link ID was specified, validate that it
729 * is indeed active.
730 */
731 if (ieee80211_vif_is_mld(&sdata->vif) && req->tsf_report_link_id >= 0 &&
732 !(sdata->vif.active_links & BIT(req->tsf_report_link_id)))
733 return -EINVAL;
734
735 if (!__ieee80211_can_leave_ch(sdata))
736 return -EBUSY;
737
738 if (!ieee80211_can_scan(local, sdata)) {
739 /* wait for the work to finish/time out */
740 rcu_assign_pointer(local->scan_req, req);
741 rcu_assign_pointer(local->scan_sdata, sdata);
742 return 0;
743 }
744
745 again:
746 if (hw_scan) {
747 u8 *ies;
748
749 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len;
750
751 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
752 int i, n_bands = 0;
753 u8 bands_counted = 0;
754
755 for (i = 0; i < req->n_channels; i++) {
756 if (bands_counted & BIT(req->channels[i]->band))
757 continue;
758 bands_counted |= BIT(req->channels[i]->band);
759 n_bands++;
760 }
761
762 local->hw_scan_ies_bufsize *= n_bands;
763 }
764
765 local->hw_scan_req = kmalloc(struct_size(local->hw_scan_req,
766 req.channels,
767 req->n_channels) +
768 local->hw_scan_ies_bufsize,
769 GFP_KERNEL);
770 if (!local->hw_scan_req)
771 return -ENOMEM;
772
773 local->hw_scan_req->req.ssids = req->ssids;
774 local->hw_scan_req->req.n_ssids = req->n_ssids;
775 /* None of the channels are actually set
776 * up but let UBSAN know the boundaries.
777 */
778 local->hw_scan_req->req.n_channels = req->n_channels;
779
780 ies = (u8 *)local->hw_scan_req +
781 sizeof(*local->hw_scan_req) +
782 req->n_channels * sizeof(req->channels[0]);
783 local->hw_scan_req->req.ie = ies;
784 local->hw_scan_req->req.flags = req->flags;
785 eth_broadcast_addr(local->hw_scan_req->req.bssid);
786 local->hw_scan_req->req.duration = req->duration;
787 local->hw_scan_req->req.duration_mandatory =
788 req->duration_mandatory;
789 local->hw_scan_req->req.tsf_report_link_id =
790 req->tsf_report_link_id;
791
792 local->hw_scan_band = 0;
793 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params;
794 local->hw_scan_req->req.scan_6ghz_params =
795 req->scan_6ghz_params;
796 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz;
797
798 /*
799 * After allocating local->hw_scan_req, we must
800 * go through until ieee80211_prep_hw_scan(), so
801 * anything that might be changed here and leave
802 * this function early must not go after this
803 * allocation.
804 */
805 }
806
807 rcu_assign_pointer(local->scan_req, req);
808 rcu_assign_pointer(local->scan_sdata, sdata);
809
810 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
811 get_random_mask_addr(local->scan_addr,
812 req->mac_addr,
813 req->mac_addr_mask);
814 else
815 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN);
816
817 if (hw_scan) {
818 __set_bit(SCAN_HW_SCANNING, &local->scanning);
819 } else if ((req->n_channels == 1) &&
820 (req->channels[0] == local->hw.conf.chandef.chan)) {
821 /*
822 * If we are scanning only on the operating channel
823 * then we do not need to stop normal activities
824 */
825 unsigned long next_delay;
826
827 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
828
829 ieee80211_recalc_idle(local);
830
831 /* Notify driver scan is starting, keep order of operations
832 * same as normal software scan, in case that matters. */
833 drv_sw_scan_start(local, sdata, local->scan_addr);
834
835 ieee80211_configure_filter(local); /* accept probe-responses */
836
837 /* We need to ensure power level is at max for scanning. */
838 ieee80211_hw_conf_chan(local);
839
840 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR |
841 IEEE80211_CHAN_RADAR)) ||
842 !req->n_ssids) {
843 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
844 if (req->n_ssids)
845 set_bit(SCAN_BEACON_WAIT, &local->scanning);
846 } else {
847 ieee80211_scan_state_send_probe(local, &next_delay);
848 next_delay = IEEE80211_CHANNEL_TIME;
849 }
850
851 /* Now, just wait a bit and we are all done! */
852 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work,
853 next_delay);
854 return 0;
855 } else {
856 /* Do normal software scan */
857 __set_bit(SCAN_SW_SCANNING, &local->scanning);
858 }
859
860 ieee80211_recalc_idle(local);
861
862 if (hw_scan) {
863 WARN_ON(!ieee80211_prep_hw_scan(sdata));
864 rc = drv_hw_scan(local, sdata, local->hw_scan_req);
865 } else {
866 rc = ieee80211_start_sw_scan(local, sdata);
867 }
868
869 if (rc) {
870 kfree(local->hw_scan_req);
871 local->hw_scan_req = NULL;
872 local->scanning = 0;
873
874 ieee80211_recalc_idle(local);
875
876 local->scan_req = NULL;
877 RCU_INIT_POINTER(local->scan_sdata, NULL);
878 }
879
880 if (hw_scan && rc == 1) {
881 /*
882 * we can't fall back to software for P2P-GO
883 * as it must update NoA etc.
884 */
885 if (ieee80211_vif_type_p2p(&sdata->vif) ==
886 NL80211_IFTYPE_P2P_GO)
887 return -EOPNOTSUPP;
888 hw_scan = false;
889 goto again;
890 }
891
892 return rc;
893 }
894
895 static unsigned long
ieee80211_scan_get_channel_time(struct ieee80211_channel * chan)896 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
897 {
898 /*
899 * TODO: channel switching also consumes quite some time,
900 * add that delay as well to get a better estimation
901 */
902 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR))
903 return IEEE80211_PASSIVE_CHANNEL_TIME;
904 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
905 }
906
ieee80211_scan_state_decision(struct ieee80211_local * local,unsigned long * next_delay)907 static void ieee80211_scan_state_decision(struct ieee80211_local *local,
908 unsigned long *next_delay)
909 {
910 bool associated = false;
911 bool tx_empty = true;
912 bool bad_latency;
913 struct ieee80211_sub_if_data *sdata;
914 struct ieee80211_channel *next_chan;
915 enum mac80211_scan_state next_scan_state;
916 struct cfg80211_scan_request *scan_req;
917
918 lockdep_assert_wiphy(local->hw.wiphy);
919
920 /*
921 * check if at least one STA interface is associated,
922 * check if at least one STA interface has pending tx frames
923 * and grab the lowest used beacon interval
924 */
925 list_for_each_entry(sdata, &local->interfaces, list) {
926 if (!ieee80211_sdata_running(sdata))
927 continue;
928
929 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
930 if (sdata->u.mgd.associated) {
931 associated = true;
932
933 if (!qdisc_all_tx_empty(sdata->dev)) {
934 tx_empty = false;
935 break;
936 }
937 }
938 }
939 }
940
941 scan_req = rcu_dereference_protected(local->scan_req,
942 lockdep_is_held(&local->hw.wiphy->mtx));
943
944 next_chan = scan_req->channels[local->scan_channel_idx];
945
946 /*
947 * we're currently scanning a different channel, let's
948 * see if we can scan another channel without interfering
949 * with the current traffic situation.
950 *
951 * Keep good latency, do not stay off-channel more than 125 ms.
952 */
953
954 bad_latency = time_after(jiffies +
955 ieee80211_scan_get_channel_time(next_chan),
956 local->leave_oper_channel_time + HZ / 8);
957
958 if (associated && !tx_empty) {
959 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY)
960 next_scan_state = SCAN_ABORT;
961 else
962 next_scan_state = SCAN_SUSPEND;
963 } else if (associated && bad_latency) {
964 next_scan_state = SCAN_SUSPEND;
965 } else {
966 next_scan_state = SCAN_SET_CHANNEL;
967 }
968
969 local->next_scan_state = next_scan_state;
970
971 *next_delay = 0;
972 }
973
ieee80211_scan_state_set_channel(struct ieee80211_local * local,unsigned long * next_delay)974 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
975 unsigned long *next_delay)
976 {
977 int skip;
978 struct ieee80211_channel *chan;
979 struct cfg80211_scan_request *scan_req;
980
981 scan_req = rcu_dereference_protected(local->scan_req,
982 lockdep_is_held(&local->hw.wiphy->mtx));
983
984 skip = 0;
985 chan = scan_req->channels[local->scan_channel_idx];
986
987 local->scan_chandef.chan = chan;
988 local->scan_chandef.center_freq1 = chan->center_freq;
989 local->scan_chandef.freq1_offset = chan->freq_offset;
990 local->scan_chandef.center_freq2 = 0;
991
992 /* For scanning on the S1G band, detect the channel width according to
993 * the channel being scanned.
994 */
995 if (chan->band == NL80211_BAND_S1GHZ) {
996 local->scan_chandef.width = ieee80211_s1g_channel_width(chan);
997 goto set_channel;
998 }
999
1000 /* If scanning on oper channel, use whatever channel-type
1001 * is currently in use.
1002 */
1003 if (chan == local->hw.conf.chandef.chan)
1004 local->scan_chandef = local->hw.conf.chandef;
1005 else
1006 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
1007
1008 set_channel:
1009 if (ieee80211_hw_conf_chan(local))
1010 skip = 1;
1011
1012 /* advance state machine to next channel/band */
1013 local->scan_channel_idx++;
1014
1015 if (skip) {
1016 /* if we skip this channel return to the decision state */
1017 local->next_scan_state = SCAN_DECISION;
1018 return;
1019 }
1020
1021 /*
1022 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
1023 * (which unfortunately doesn't say _why_ step a) is done,
1024 * but it waits for the probe delay or until a frame is
1025 * received - and the received frame would update the NAV).
1026 * For now, we do not support waiting until a frame is
1027 * received.
1028 *
1029 * In any case, it is not necessary for a passive scan.
1030 */
1031 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) ||
1032 !scan_req->n_ssids) {
1033 *next_delay = max(msecs_to_jiffies(scan_req->duration),
1034 IEEE80211_PASSIVE_CHANNEL_TIME);
1035 local->next_scan_state = SCAN_DECISION;
1036 if (scan_req->n_ssids)
1037 set_bit(SCAN_BEACON_WAIT, &local->scanning);
1038 return;
1039 }
1040
1041 /* active scan, send probes */
1042 *next_delay = IEEE80211_PROBE_DELAY;
1043 local->next_scan_state = SCAN_SEND_PROBE;
1044 }
1045
ieee80211_scan_state_suspend(struct ieee80211_local * local,unsigned long * next_delay)1046 static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
1047 unsigned long *next_delay)
1048 {
1049 /* switch back to the operating channel */
1050 local->scan_chandef.chan = NULL;
1051 ieee80211_hw_conf_chan(local);
1052
1053 /* disable PS */
1054 ieee80211_offchannel_return(local);
1055
1056 *next_delay = HZ / 5;
1057 /* afterwards, resume scan & go to next channel */
1058 local->next_scan_state = SCAN_RESUME;
1059 }
1060
ieee80211_scan_state_resume(struct ieee80211_local * local,unsigned long * next_delay)1061 static void ieee80211_scan_state_resume(struct ieee80211_local *local,
1062 unsigned long *next_delay)
1063 {
1064 ieee80211_offchannel_stop_vifs(local);
1065
1066 if (local->ops->flush) {
1067 ieee80211_flush_queues(local, NULL, false);
1068 *next_delay = 0;
1069 } else
1070 *next_delay = HZ / 10;
1071
1072 /* remember when we left the operating channel */
1073 local->leave_oper_channel_time = jiffies;
1074
1075 /* advance to the next channel to be scanned */
1076 local->next_scan_state = SCAN_SET_CHANNEL;
1077 }
1078
ieee80211_scan_work(struct wiphy * wiphy,struct wiphy_work * work)1079 void ieee80211_scan_work(struct wiphy *wiphy, struct wiphy_work *work)
1080 {
1081 struct ieee80211_local *local =
1082 container_of(work, struct ieee80211_local, scan_work.work);
1083 struct ieee80211_sub_if_data *sdata;
1084 struct cfg80211_scan_request *scan_req;
1085 unsigned long next_delay = 0;
1086 bool aborted;
1087
1088 lockdep_assert_wiphy(local->hw.wiphy);
1089
1090 if (!ieee80211_can_run_worker(local)) {
1091 aborted = true;
1092 goto out_complete;
1093 }
1094
1095 sdata = rcu_dereference_protected(local->scan_sdata,
1096 lockdep_is_held(&local->hw.wiphy->mtx));
1097 scan_req = rcu_dereference_protected(local->scan_req,
1098 lockdep_is_held(&local->hw.wiphy->mtx));
1099
1100 /* When scanning on-channel, the first-callback means completed. */
1101 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) {
1102 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
1103 goto out_complete;
1104 }
1105
1106 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) {
1107 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
1108 goto out_complete;
1109 }
1110
1111 if (!sdata || !scan_req)
1112 return;
1113
1114 if (!local->scanning) {
1115 int rc;
1116
1117 RCU_INIT_POINTER(local->scan_req, NULL);
1118 RCU_INIT_POINTER(local->scan_sdata, NULL);
1119
1120 rc = __ieee80211_start_scan(sdata, scan_req);
1121 if (!rc)
1122 return;
1123 /* need to complete scan in cfg80211 */
1124 rcu_assign_pointer(local->scan_req, scan_req);
1125 aborted = true;
1126 goto out_complete;
1127 }
1128
1129 clear_bit(SCAN_BEACON_WAIT, &local->scanning);
1130
1131 /*
1132 * as long as no delay is required advance immediately
1133 * without scheduling a new work
1134 */
1135 do {
1136 if (!ieee80211_sdata_running(sdata)) {
1137 aborted = true;
1138 goto out_complete;
1139 }
1140
1141 if (test_and_clear_bit(SCAN_BEACON_DONE, &local->scanning) &&
1142 local->next_scan_state == SCAN_DECISION)
1143 local->next_scan_state = SCAN_SEND_PROBE;
1144
1145 switch (local->next_scan_state) {
1146 case SCAN_DECISION:
1147 /* if no more bands/channels left, complete scan */
1148 if (local->scan_channel_idx >= scan_req->n_channels) {
1149 aborted = false;
1150 goto out_complete;
1151 }
1152 ieee80211_scan_state_decision(local, &next_delay);
1153 break;
1154 case SCAN_SET_CHANNEL:
1155 ieee80211_scan_state_set_channel(local, &next_delay);
1156 break;
1157 case SCAN_SEND_PROBE:
1158 ieee80211_scan_state_send_probe(local, &next_delay);
1159 break;
1160 case SCAN_SUSPEND:
1161 ieee80211_scan_state_suspend(local, &next_delay);
1162 break;
1163 case SCAN_RESUME:
1164 ieee80211_scan_state_resume(local, &next_delay);
1165 break;
1166 case SCAN_ABORT:
1167 aborted = true;
1168 goto out_complete;
1169 }
1170 } while (next_delay == 0);
1171
1172 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work,
1173 next_delay);
1174 return;
1175
1176 out_complete:
1177 __ieee80211_scan_completed(&local->hw, aborted);
1178 }
1179
ieee80211_request_scan(struct ieee80211_sub_if_data * sdata,struct cfg80211_scan_request * req)1180 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
1181 struct cfg80211_scan_request *req)
1182 {
1183 lockdep_assert_wiphy(sdata->local->hw.wiphy);
1184
1185 return __ieee80211_start_scan(sdata, req);
1186 }
1187
ieee80211_request_ibss_scan(struct ieee80211_sub_if_data * sdata,const u8 * ssid,u8 ssid_len,struct ieee80211_channel ** channels,unsigned int n_channels)1188 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
1189 const u8 *ssid, u8 ssid_len,
1190 struct ieee80211_channel **channels,
1191 unsigned int n_channels)
1192 {
1193 struct ieee80211_local *local = sdata->local;
1194 int i, n_ch = 0;
1195 enum nl80211_band band;
1196
1197 lockdep_assert_wiphy(local->hw.wiphy);
1198
1199 /* busy scanning */
1200 if (local->scan_req)
1201 return -EBUSY;
1202
1203 /* fill internal scan request */
1204 if (!channels) {
1205 int max_n;
1206
1207 for (band = 0; band < NUM_NL80211_BANDS; band++) {
1208 if (!local->hw.wiphy->bands[band] ||
1209 band == NL80211_BAND_6GHZ)
1210 continue;
1211
1212 max_n = local->hw.wiphy->bands[band]->n_channels;
1213 for (i = 0; i < max_n; i++) {
1214 struct ieee80211_channel *tmp_ch =
1215 &local->hw.wiphy->bands[band]->channels[i];
1216
1217 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR |
1218 IEEE80211_CHAN_DISABLED) ||
1219 !cfg80211_wdev_channel_allowed(&sdata->wdev,
1220 tmp_ch))
1221 continue;
1222
1223 local->int_scan_req->channels[n_ch] = tmp_ch;
1224 n_ch++;
1225 }
1226 }
1227
1228 if (WARN_ON_ONCE(n_ch == 0))
1229 return -EINVAL;
1230
1231 local->int_scan_req->n_channels = n_ch;
1232 } else {
1233 for (i = 0; i < n_channels; i++) {
1234 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR |
1235 IEEE80211_CHAN_DISABLED) ||
1236 !cfg80211_wdev_channel_allowed(&sdata->wdev,
1237 channels[i]))
1238 continue;
1239
1240 local->int_scan_req->channels[n_ch] = channels[i];
1241 n_ch++;
1242 }
1243
1244 if (n_ch == 0)
1245 return -EINVAL;
1246
1247 local->int_scan_req->n_channels = n_ch;
1248 }
1249
1250 local->int_scan_req->ssids = &local->scan_ssid;
1251 local->int_scan_req->n_ssids = 1;
1252 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
1253 local->int_scan_req->ssids[0].ssid_len = ssid_len;
1254
1255 return __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
1256 }
1257
ieee80211_scan_cancel(struct ieee80211_local * local)1258 void ieee80211_scan_cancel(struct ieee80211_local *local)
1259 {
1260 /* ensure a new scan cannot be queued */
1261 lockdep_assert_wiphy(local->hw.wiphy);
1262
1263 /*
1264 * We are canceling software scan, or deferred scan that was not
1265 * yet really started (see __ieee80211_start_scan ).
1266 *
1267 * Regarding hardware scan:
1268 * - we can not call __ieee80211_scan_completed() as when
1269 * SCAN_HW_SCANNING bit is set this function change
1270 * local->hw_scan_req to operate on 5G band, what race with
1271 * driver which can use local->hw_scan_req
1272 *
1273 * - we can not cancel scan_work since driver can schedule it
1274 * by ieee80211_scan_completed(..., true) to finish scan
1275 *
1276 * Hence we only call the cancel_hw_scan() callback, but the low-level
1277 * driver is still responsible for calling ieee80211_scan_completed()
1278 * after the scan was completed/aborted.
1279 */
1280
1281 if (!local->scan_req)
1282 return;
1283
1284 /*
1285 * We have a scan running and the driver already reported completion,
1286 * but the worker hasn't run yet or is stuck on the mutex - mark it as
1287 * cancelled.
1288 */
1289 if (test_bit(SCAN_HW_SCANNING, &local->scanning) &&
1290 test_bit(SCAN_COMPLETED, &local->scanning)) {
1291 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1292 return;
1293 }
1294
1295 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
1296 /*
1297 * Make sure that __ieee80211_scan_completed doesn't trigger a
1298 * scan on another band.
1299 */
1300 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1301 if (local->ops->cancel_hw_scan)
1302 drv_cancel_hw_scan(local,
1303 rcu_dereference_protected(local->scan_sdata,
1304 lockdep_is_held(&local->hw.wiphy->mtx)));
1305 return;
1306 }
1307
1308 wiphy_delayed_work_cancel(local->hw.wiphy, &local->scan_work);
1309 /* and clean up */
1310 memset(&local->scan_info, 0, sizeof(local->scan_info));
1311 __ieee80211_scan_completed(&local->hw, true);
1312 }
1313
__ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data * sdata,struct cfg80211_sched_scan_request * req)1314 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1315 struct cfg80211_sched_scan_request *req)
1316 {
1317 struct ieee80211_local *local = sdata->local;
1318 struct ieee80211_scan_ies sched_scan_ies = {};
1319 struct cfg80211_chan_def chandef;
1320 int ret, i, iebufsz, num_bands = 0;
1321 u32 rate_masks[NUM_NL80211_BANDS] = {};
1322 u8 bands_used = 0;
1323 u8 *ie;
1324 u32 flags = 0;
1325
1326 lockdep_assert_wiphy(local->hw.wiphy);
1327
1328 iebufsz = local->scan_ies_len + req->ie_len;
1329
1330 if (!local->ops->sched_scan_start)
1331 return -EOPNOTSUPP;
1332
1333 for (i = 0; i < NUM_NL80211_BANDS; i++) {
1334 if (local->hw.wiphy->bands[i]) {
1335 bands_used |= BIT(i);
1336 rate_masks[i] = (u32) -1;
1337 num_bands++;
1338 }
1339 }
1340
1341 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
1342 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
1343
1344 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL);
1345 if (!ie) {
1346 ret = -ENOMEM;
1347 goto out;
1348 }
1349
1350 ieee80211_prepare_scan_chandef(&chandef);
1351
1352 ret = ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz,
1353 &sched_scan_ies, req->ie,
1354 req->ie_len, bands_used, rate_masks,
1355 &chandef, flags);
1356 if (ret < 0)
1357 goto error;
1358
1359 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
1360 if (ret == 0) {
1361 rcu_assign_pointer(local->sched_scan_sdata, sdata);
1362 rcu_assign_pointer(local->sched_scan_req, req);
1363 }
1364
1365 error:
1366 kfree(ie);
1367 out:
1368 if (ret) {
1369 /* Clean in case of failure after HW restart or upon resume. */
1370 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1371 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1372 }
1373
1374 return ret;
1375 }
1376
ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data * sdata,struct cfg80211_sched_scan_request * req)1377 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1378 struct cfg80211_sched_scan_request *req)
1379 {
1380 struct ieee80211_local *local = sdata->local;
1381
1382 lockdep_assert_wiphy(local->hw.wiphy);
1383
1384 if (rcu_access_pointer(local->sched_scan_sdata))
1385 return -EBUSY;
1386
1387 return __ieee80211_request_sched_scan_start(sdata, req);
1388 }
1389
ieee80211_request_sched_scan_stop(struct ieee80211_local * local)1390 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local)
1391 {
1392 struct ieee80211_sub_if_data *sched_scan_sdata;
1393 int ret = -ENOENT;
1394
1395 lockdep_assert_wiphy(local->hw.wiphy);
1396
1397 if (!local->ops->sched_scan_stop)
1398 return -EOPNOTSUPP;
1399
1400 /* We don't want to restart sched scan anymore. */
1401 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1402
1403 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata,
1404 lockdep_is_held(&local->hw.wiphy->mtx));
1405 if (sched_scan_sdata) {
1406 ret = drv_sched_scan_stop(local, sched_scan_sdata);
1407 if (!ret)
1408 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1409 }
1410
1411 return ret;
1412 }
1413
ieee80211_sched_scan_results(struct ieee80211_hw * hw)1414 void ieee80211_sched_scan_results(struct ieee80211_hw *hw)
1415 {
1416 struct ieee80211_local *local = hw_to_local(hw);
1417
1418 trace_api_sched_scan_results(local);
1419
1420 cfg80211_sched_scan_results(hw->wiphy, 0);
1421 }
1422 EXPORT_SYMBOL(ieee80211_sched_scan_results);
1423
ieee80211_sched_scan_end(struct ieee80211_local * local)1424 void ieee80211_sched_scan_end(struct ieee80211_local *local)
1425 {
1426 lockdep_assert_wiphy(local->hw.wiphy);
1427
1428 if (!rcu_access_pointer(local->sched_scan_sdata))
1429 return;
1430
1431 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1432
1433 /* If sched scan was aborted by the driver. */
1434 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1435
1436 cfg80211_sched_scan_stopped_locked(local->hw.wiphy, 0);
1437 }
1438
ieee80211_sched_scan_stopped_work(struct wiphy * wiphy,struct wiphy_work * work)1439 void ieee80211_sched_scan_stopped_work(struct wiphy *wiphy,
1440 struct wiphy_work *work)
1441 {
1442 struct ieee80211_local *local =
1443 container_of(work, struct ieee80211_local,
1444 sched_scan_stopped_work);
1445
1446 ieee80211_sched_scan_end(local);
1447 }
1448
ieee80211_sched_scan_stopped(struct ieee80211_hw * hw)1449 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
1450 {
1451 struct ieee80211_local *local = hw_to_local(hw);
1452
1453 trace_api_sched_scan_stopped(local);
1454
1455 /*
1456 * this shouldn't really happen, so for simplicity
1457 * simply ignore it, and let mac80211 reconfigure
1458 * the sched scan later on.
1459 */
1460 if (local->in_reconfig)
1461 return;
1462
1463 wiphy_work_queue(hw->wiphy, &local->sched_scan_stopped_work);
1464 }
1465 EXPORT_SYMBOL(ieee80211_sched_scan_stopped);
1466