Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Scanning implementation
4 *
5 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
6 * Copyright 2004, Instant802 Networks, Inc.
7 * Copyright 2005, Devicescape Software, Inc.
8 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
9 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
10 * Copyright 2013-2015 Intel Mobile Communications GmbH
11 * Copyright 2016-2017 Intel Deutschland GmbH
12 * Copyright (C) 2018-2021 Intel Corporation
13 */
14
15#include <linux/if_arp.h>
16#include <linux/etherdevice.h>
17#include <linux/rtnetlink.h>
18#include <net/sch_generic.h>
19#include <linux/slab.h>
20#include <linux/export.h>
21#include <linux/random.h>
22#include <net/mac80211.h>
23
24#include "ieee80211_i.h"
25#include "driver-ops.h"
26#include "mesh.h"
27
28#define IEEE80211_PROBE_DELAY (HZ / 33)
29#define IEEE80211_CHANNEL_TIME (HZ / 33)
30#define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 9)
31
32void ieee80211_rx_bss_put(struct ieee80211_local *local,
33 struct ieee80211_bss *bss)
34{
35 if (!bss)
36 return;
37 cfg80211_put_bss(local->hw.wiphy,
38 container_of((void *)bss, struct cfg80211_bss, priv));
39}
40
41static bool is_uapsd_supported(struct ieee802_11_elems *elems)
42{
43 u8 qos_info;
44
45 if (elems->wmm_info && elems->wmm_info_len == 7
46 && elems->wmm_info[5] == 1)
47 qos_info = elems->wmm_info[6];
48 else if (elems->wmm_param && elems->wmm_param_len == 24
49 && elems->wmm_param[5] == 1)
50 qos_info = elems->wmm_param[6];
51 else
52 /* no valid wmm information or parameter element found */
53 return false;
54
55 return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD;
56}
57
58static void
59ieee80211_update_bss_from_elems(struct ieee80211_local *local,
60 struct ieee80211_bss *bss,
61 struct ieee802_11_elems *elems,
62 struct ieee80211_rx_status *rx_status,
63 bool beacon)
64{
65 int clen, srlen;
66
67 if (beacon)
68 bss->device_ts_beacon = rx_status->device_timestamp;
69 else
70 bss->device_ts_presp = rx_status->device_timestamp;
71
72 if (elems->parse_error) {
73 if (beacon)
74 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON;
75 else
76 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP;
77 } else {
78 if (beacon)
79 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON;
80 else
81 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP;
82 }
83
84 /* save the ERP value so that it is available at association time */
85 if (elems->erp_info && (!elems->parse_error ||
86 !(bss->valid_data & IEEE80211_BSS_VALID_ERP))) {
87 bss->erp_value = elems->erp_info[0];
88 bss->has_erp_value = true;
89 if (!elems->parse_error)
90 bss->valid_data |= IEEE80211_BSS_VALID_ERP;
91 }
92
93 /* replace old supported rates if we get new values */
94 if (!elems->parse_error ||
95 !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) {
96 srlen = 0;
97 if (elems->supp_rates) {
98 clen = IEEE80211_MAX_SUPP_RATES;
99 if (clen > elems->supp_rates_len)
100 clen = elems->supp_rates_len;
101 memcpy(bss->supp_rates, elems->supp_rates, clen);
102 srlen += clen;
103 }
104 if (elems->ext_supp_rates) {
105 clen = IEEE80211_MAX_SUPP_RATES - srlen;
106 if (clen > elems->ext_supp_rates_len)
107 clen = elems->ext_supp_rates_len;
108 memcpy(bss->supp_rates + srlen, elems->ext_supp_rates,
109 clen);
110 srlen += clen;
111 }
112 if (srlen) {
113 bss->supp_rates_len = srlen;
114 if (!elems->parse_error)
115 bss->valid_data |= IEEE80211_BSS_VALID_RATES;
116 }
117 }
118
119 if (!elems->parse_error ||
120 !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) {
121 bss->wmm_used = elems->wmm_param || elems->wmm_info;
122 bss->uapsd_supported = is_uapsd_supported(elems);
123 if (!elems->parse_error)
124 bss->valid_data |= IEEE80211_BSS_VALID_WMM;
125 }
126
127 if (beacon) {
128 struct ieee80211_supported_band *sband =
129 local->hw.wiphy->bands[rx_status->band];
130 if (!(rx_status->encoding == RX_ENC_HT) &&
131 !(rx_status->encoding == RX_ENC_VHT))
132 bss->beacon_rate =
133 &sband->bitrates[rx_status->rate_idx];
134 }
135
136 if (elems->vht_cap_elem)
137 bss->vht_cap_info =
138 le32_to_cpu(elems->vht_cap_elem->vht_cap_info);
139 else
140 bss->vht_cap_info = 0;
141}
142
143struct ieee80211_bss *
144ieee80211_bss_info_update(struct ieee80211_local *local,
145 struct ieee80211_rx_status *rx_status,
146 struct ieee80211_mgmt *mgmt, size_t len,
147 struct ieee80211_channel *channel)
148{
149 bool beacon = ieee80211_is_beacon(mgmt->frame_control) ||
150 ieee80211_is_s1g_beacon(mgmt->frame_control);
151 struct cfg80211_bss *cbss, *non_tx_cbss;
152 struct ieee80211_bss *bss, *non_tx_bss;
153 struct cfg80211_inform_bss bss_meta = {
154 .boottime_ns = rx_status->boottime_ns,
155 };
156 bool signal_valid;
157 struct ieee80211_sub_if_data *scan_sdata;
158 struct ieee802_11_elems *elems;
159 size_t baselen;
160 u8 *elements;
161
162 if (rx_status->flag & RX_FLAG_NO_SIGNAL_VAL)
163 bss_meta.signal = 0; /* invalid signal indication */
164 else if (ieee80211_hw_check(&local->hw, SIGNAL_DBM))
165 bss_meta.signal = rx_status->signal * 100;
166 else if (ieee80211_hw_check(&local->hw, SIGNAL_UNSPEC))
167 bss_meta.signal = (rx_status->signal * 100) / local->hw.max_signal;
168
169 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_20;
170 if (rx_status->bw == RATE_INFO_BW_5)
171 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_5;
172 else if (rx_status->bw == RATE_INFO_BW_10)
173 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_10;
174
175 bss_meta.chan = channel;
176
177 rcu_read_lock();
178 scan_sdata = rcu_dereference(local->scan_sdata);
179 if (scan_sdata && scan_sdata->vif.type == NL80211_IFTYPE_STATION &&
180 scan_sdata->vif.cfg.assoc &&
181 ieee80211_have_rx_timestamp(rx_status)) {
182 bss_meta.parent_tsf =
183 ieee80211_calculate_rx_timestamp(local, rx_status,
184 len + FCS_LEN, 24);
185 ether_addr_copy(bss_meta.parent_bssid,
186 scan_sdata->vif.bss_conf.bssid);
187 }
188 rcu_read_unlock();
189
190 cbss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta,
191 mgmt, len, GFP_ATOMIC);
192 if (!cbss)
193 return NULL;
194
195 if (ieee80211_is_probe_resp(mgmt->frame_control)) {
196 elements = mgmt->u.probe_resp.variable;
197 baselen = offsetof(struct ieee80211_mgmt,
198 u.probe_resp.variable);
199 } else if (ieee80211_is_s1g_beacon(mgmt->frame_control)) {
200 struct ieee80211_ext *ext = (void *) mgmt;
201
202 baselen = offsetof(struct ieee80211_ext, u.s1g_beacon.variable);
203 elements = ext->u.s1g_beacon.variable;
204 } else {
205 baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable);
206 elements = mgmt->u.beacon.variable;
207 }
208
209 if (baselen > len)
210 return NULL;
211
212 elems = ieee802_11_parse_elems(elements, len - baselen, false, cbss);
213 if (!elems)
214 return NULL;
215
216 /* In case the signal is invalid update the status */
217 signal_valid = channel == cbss->channel;
218 if (!signal_valid)
219 rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL;
220
221 bss = (void *)cbss->priv;
222 ieee80211_update_bss_from_elems(local, bss, elems, rx_status, beacon);
223 kfree(elems);
224
225 list_for_each_entry(non_tx_cbss, &cbss->nontrans_list, nontrans_list) {
226 non_tx_bss = (void *)non_tx_cbss->priv;
227
228 elems = ieee802_11_parse_elems(elements, len - baselen, false,
229 non_tx_cbss);
230 if (!elems)
231 continue;
232
233 ieee80211_update_bss_from_elems(local, non_tx_bss, elems,
234 rx_status, beacon);
235 kfree(elems);
236 }
237
238 return bss;
239}
240
241static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata,
242 u32 scan_flags, const u8 *da)
243{
244 if (!sdata)
245 return false;
246 /* accept broadcast for OCE */
247 if (scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP &&
248 is_broadcast_ether_addr(da))
249 return true;
250 if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
251 return true;
252 return ether_addr_equal(da, sdata->vif.addr);
253}
254
255void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb)
256{
257 struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
258 struct ieee80211_sub_if_data *sdata1, *sdata2;
259 struct ieee80211_mgmt *mgmt = (void *)skb->data;
260 struct ieee80211_bss *bss;
261 struct ieee80211_channel *channel;
262 size_t min_hdr_len = offsetof(struct ieee80211_mgmt,
263 u.probe_resp.variable);
264
265 if (!ieee80211_is_probe_resp(mgmt->frame_control) &&
266 !ieee80211_is_beacon(mgmt->frame_control) &&
267 !ieee80211_is_s1g_beacon(mgmt->frame_control))
268 return;
269
270 if (ieee80211_is_s1g_beacon(mgmt->frame_control)) {
271 if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
272 min_hdr_len = offsetof(struct ieee80211_ext,
273 u.s1g_short_beacon.variable);
274 else
275 min_hdr_len = offsetof(struct ieee80211_ext,
276 u.s1g_beacon);
277 }
278
279 if (skb->len < min_hdr_len)
280 return;
281
282 sdata1 = rcu_dereference(local->scan_sdata);
283 sdata2 = rcu_dereference(local->sched_scan_sdata);
284
285 if (likely(!sdata1 && !sdata2))
286 return;
287
288 if (test_and_clear_bit(SCAN_BEACON_WAIT, &local->scanning)) {
289 /*
290 * we were passive scanning because of radar/no-IR, but
291 * the beacon/proberesp rx gives us an opportunity to upgrade
292 * to active scan
293 */
294 set_bit(SCAN_BEACON_DONE, &local->scanning);
295 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
296 }
297
298 if (ieee80211_is_probe_resp(mgmt->frame_control)) {
299 struct cfg80211_scan_request *scan_req;
300 struct cfg80211_sched_scan_request *sched_scan_req;
301 u32 scan_req_flags = 0, sched_scan_req_flags = 0;
302
303 scan_req = rcu_dereference(local->scan_req);
304 sched_scan_req = rcu_dereference(local->sched_scan_req);
305
306 if (scan_req)
307 scan_req_flags = scan_req->flags;
308
309 if (sched_scan_req)
310 sched_scan_req_flags = sched_scan_req->flags;
311
312 /* ignore ProbeResp to foreign address or non-bcast (OCE)
313 * unless scanning with randomised address
314 */
315 if (!ieee80211_scan_accept_presp(sdata1, scan_req_flags,
316 mgmt->da) &&
317 !ieee80211_scan_accept_presp(sdata2, sched_scan_req_flags,
318 mgmt->da))
319 return;
320 }
321
322 channel = ieee80211_get_channel_khz(local->hw.wiphy,
323 ieee80211_rx_status_to_khz(rx_status));
324
325 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
326 return;
327
328 bss = ieee80211_bss_info_update(local, rx_status,
329 mgmt, skb->len,
330 channel);
331 if (bss)
332 ieee80211_rx_bss_put(local, bss);
333}
334
335static void
336ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef,
337 enum nl80211_bss_scan_width scan_width)
338{
339 memset(chandef, 0, sizeof(*chandef));
340 switch (scan_width) {
341 case NL80211_BSS_CHAN_WIDTH_5:
342 chandef->width = NL80211_CHAN_WIDTH_5;
343 break;
344 case NL80211_BSS_CHAN_WIDTH_10:
345 chandef->width = NL80211_CHAN_WIDTH_10;
346 break;
347 default:
348 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
349 break;
350 }
351}
352
353/* return false if no more work */
354static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data *sdata)
355{
356 struct ieee80211_local *local = sdata->local;
357 struct cfg80211_scan_request *req;
358 struct cfg80211_chan_def chandef;
359 u8 bands_used = 0;
360 int i, ielen, n_chans;
361 u32 flags = 0;
362
363 req = rcu_dereference_protected(local->scan_req,
364 lockdep_is_held(&local->mtx));
365
366 if (test_bit(SCAN_HW_CANCELLED, &local->scanning))
367 return false;
368
369 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
370 for (i = 0; i < req->n_channels; i++) {
371 local->hw_scan_req->req.channels[i] = req->channels[i];
372 bands_used |= BIT(req->channels[i]->band);
373 }
374
375 n_chans = req->n_channels;
376 } else {
377 do {
378 if (local->hw_scan_band == NUM_NL80211_BANDS)
379 return false;
380
381 n_chans = 0;
382
383 for (i = 0; i < req->n_channels; i++) {
384 if (req->channels[i]->band !=
385 local->hw_scan_band)
386 continue;
387 local->hw_scan_req->req.channels[n_chans] =
388 req->channels[i];
389 n_chans++;
390 bands_used |= BIT(req->channels[i]->band);
391 }
392
393 local->hw_scan_band++;
394 } while (!n_chans);
395 }
396
397 local->hw_scan_req->req.n_channels = n_chans;
398 ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
399
400 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
401 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
402
403 ielen = ieee80211_build_preq_ies(sdata,
404 (u8 *)local->hw_scan_req->req.ie,
405 local->hw_scan_ies_bufsize,
406 &local->hw_scan_req->ies,
407 req->ie, req->ie_len,
408 bands_used, req->rates, &chandef,
409 flags);
410 local->hw_scan_req->req.ie_len = ielen;
411 local->hw_scan_req->req.no_cck = req->no_cck;
412 ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr);
413 ether_addr_copy(local->hw_scan_req->req.mac_addr_mask,
414 req->mac_addr_mask);
415 ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid);
416
417 return true;
418}
419
420static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
421{
422 struct ieee80211_local *local = hw_to_local(hw);
423 bool hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning);
424 bool was_scanning = local->scanning;
425 struct cfg80211_scan_request *scan_req;
426 struct ieee80211_sub_if_data *scan_sdata;
427 struct ieee80211_sub_if_data *sdata;
428
429 lockdep_assert_held(&local->mtx);
430
431 /*
432 * It's ok to abort a not-yet-running scan (that
433 * we have one at all will be verified by checking
434 * local->scan_req next), but not to complete it
435 * successfully.
436 */
437 if (WARN_ON(!local->scanning && !aborted))
438 aborted = true;
439
440 if (WARN_ON(!local->scan_req))
441 return;
442
443 scan_sdata = rcu_dereference_protected(local->scan_sdata,
444 lockdep_is_held(&local->mtx));
445
446 if (hw_scan && !aborted &&
447 !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) &&
448 ieee80211_prep_hw_scan(scan_sdata)) {
449 int rc;
450
451 rc = drv_hw_scan(local,
452 rcu_dereference_protected(local->scan_sdata,
453 lockdep_is_held(&local->mtx)),
454 local->hw_scan_req);
455
456 if (rc == 0)
457 return;
458
459 /* HW scan failed and is going to be reported as aborted,
460 * so clear old scan info.
461 */
462 memset(&local->scan_info, 0, sizeof(local->scan_info));
463 aborted = true;
464 }
465
466 kfree(local->hw_scan_req);
467 local->hw_scan_req = NULL;
468
469 scan_req = rcu_dereference_protected(local->scan_req,
470 lockdep_is_held(&local->mtx));
471
472 if (scan_req != local->int_scan_req) {
473 local->scan_info.aborted = aborted;
474 cfg80211_scan_done(scan_req, &local->scan_info);
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 /* Set power back to normal operating levels. */
483 ieee80211_hw_config(local, 0);
484
485 if (!hw_scan) {
486 ieee80211_configure_filter(local);
487 drv_sw_scan_complete(local, scan_sdata);
488 ieee80211_offchannel_return(local);
489 }
490
491 ieee80211_recalc_idle(local);
492
493 ieee80211_mlme_notify_scan_completed(local);
494 ieee80211_ibss_notify_scan_completed(local);
495
496 /* Requeue all the work that might have been ignored while
497 * the scan was in progress; if there was none this will
498 * just be a no-op for the particular interface.
499 */
500 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
501 if (ieee80211_sdata_running(sdata))
502 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
503 }
504
505 if (was_scanning)
506 ieee80211_start_next_roc(local);
507}
508
509void ieee80211_scan_completed(struct ieee80211_hw *hw,
510 struct cfg80211_scan_info *info)
511{
512 struct ieee80211_local *local = hw_to_local(hw);
513
514 trace_api_scan_completed(local, info->aborted);
515
516 set_bit(SCAN_COMPLETED, &local->scanning);
517 if (info->aborted)
518 set_bit(SCAN_ABORTED, &local->scanning);
519
520 memcpy(&local->scan_info, info, sizeof(*info));
521
522 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
523}
524EXPORT_SYMBOL(ieee80211_scan_completed);
525
526static int ieee80211_start_sw_scan(struct ieee80211_local *local,
527 struct ieee80211_sub_if_data *sdata)
528{
529 /* Software scan is not supported in multi-channel cases */
530 if (local->use_chanctx)
531 return -EOPNOTSUPP;
532
533 /*
534 * Hardware/driver doesn't support hw_scan, so use software
535 * scanning instead. First send a nullfunc frame with power save
536 * bit on so that AP will buffer the frames for us while we are not
537 * listening, then send probe requests to each channel and wait for
538 * the responses. After all channels are scanned, tune back to the
539 * original channel and send a nullfunc frame with power save bit
540 * off to trigger the AP to send us all the buffered frames.
541 *
542 * Note that while local->sw_scanning is true everything else but
543 * nullfunc frames and probe requests will be dropped in
544 * ieee80211_tx_h_check_assoc().
545 */
546 drv_sw_scan_start(local, sdata, local->scan_addr);
547
548 local->leave_oper_channel_time = jiffies;
549 local->next_scan_state = SCAN_DECISION;
550 local->scan_channel_idx = 0;
551
552 ieee80211_offchannel_stop_vifs(local);
553
554 /* ensure nullfunc is transmitted before leaving operating channel */
555 ieee80211_flush_queues(local, NULL, false);
556
557 ieee80211_configure_filter(local);
558
559 /* We need to set power level at maximum rate for scanning. */
560 ieee80211_hw_config(local, 0);
561
562 ieee80211_queue_delayed_work(&local->hw,
563 &local->scan_work, 0);
564
565 return 0;
566}
567
568static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata)
569{
570 struct ieee80211_local *local = sdata->local;
571 struct ieee80211_sub_if_data *sdata_iter;
572
573 if (!ieee80211_is_radar_required(local))
574 return true;
575
576 if (!regulatory_pre_cac_allowed(local->hw.wiphy))
577 return false;
578
579 mutex_lock(&local->iflist_mtx);
580 list_for_each_entry(sdata_iter, &local->interfaces, list) {
581 if (sdata_iter->wdev.cac_started) {
582 mutex_unlock(&local->iflist_mtx);
583 return false;
584 }
585 }
586 mutex_unlock(&local->iflist_mtx);
587
588 return true;
589}
590
591static bool ieee80211_can_scan(struct ieee80211_local *local,
592 struct ieee80211_sub_if_data *sdata)
593{
594 if (!__ieee80211_can_leave_ch(sdata))
595 return false;
596
597 if (!list_empty(&local->roc_list))
598 return false;
599
600 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
601 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL)
602 return false;
603
604 return true;
605}
606
607void ieee80211_run_deferred_scan(struct ieee80211_local *local)
608{
609 lockdep_assert_held(&local->mtx);
610
611 if (!local->scan_req || local->scanning)
612 return;
613
614 if (!ieee80211_can_scan(local,
615 rcu_dereference_protected(
616 local->scan_sdata,
617 lockdep_is_held(&local->mtx))))
618 return;
619
620 ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
621 round_jiffies_relative(0));
622}
623
624static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata,
625 const u8 *src, const u8 *dst,
626 const u8 *ssid, size_t ssid_len,
627 const u8 *ie, size_t ie_len,
628 u32 ratemask, u32 flags, u32 tx_flags,
629 struct ieee80211_channel *channel)
630{
631 struct sk_buff *skb;
632
633 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel,
634 ssid, ssid_len,
635 ie, ie_len, flags);
636
637 if (skb) {
638 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) {
639 struct ieee80211_hdr *hdr = (void *)skb->data;
640 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
641 u16 sn = get_random_u32();
642
643 info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO;
644 hdr->seq_ctrl =
645 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn));
646 }
647 IEEE80211_SKB_CB(skb)->flags |= tx_flags;
648 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band);
649 }
650}
651
652static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
653 unsigned long *next_delay)
654{
655 int i;
656 struct ieee80211_sub_if_data *sdata;
657 struct cfg80211_scan_request *scan_req;
658 enum nl80211_band band = local->hw.conf.chandef.chan->band;
659 u32 flags = 0, tx_flags;
660
661 scan_req = rcu_dereference_protected(local->scan_req,
662 lockdep_is_held(&local->mtx));
663
664 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
665 if (scan_req->no_cck)
666 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
667 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
668 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
669 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN)
670 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN;
671
672 sdata = rcu_dereference_protected(local->scan_sdata,
673 lockdep_is_held(&local->mtx));
674
675 for (i = 0; i < scan_req->n_ssids; i++)
676 ieee80211_send_scan_probe_req(
677 sdata, local->scan_addr, scan_req->bssid,
678 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len,
679 scan_req->ie, scan_req->ie_len,
680 scan_req->rates[band], flags,
681 tx_flags, local->hw.conf.chandef.chan);
682
683 /*
684 * After sending probe requests, wait for probe responses
685 * on the channel.
686 */
687 *next_delay = IEEE80211_CHANNEL_TIME;
688 local->next_scan_state = SCAN_DECISION;
689}
690
691static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
692 struct cfg80211_scan_request *req)
693{
694 struct ieee80211_local *local = sdata->local;
695 bool hw_scan = local->ops->hw_scan;
696 int rc;
697
698 lockdep_assert_held(&local->mtx);
699
700 if (local->scan_req)
701 return -EBUSY;
702
703 if (!__ieee80211_can_leave_ch(sdata))
704 return -EBUSY;
705
706 if (!ieee80211_can_scan(local, sdata)) {
707 /* wait for the work to finish/time out */
708 rcu_assign_pointer(local->scan_req, req);
709 rcu_assign_pointer(local->scan_sdata, sdata);
710 return 0;
711 }
712
713 again:
714 if (hw_scan) {
715 u8 *ies;
716
717 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len;
718
719 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
720 int i, n_bands = 0;
721 u8 bands_counted = 0;
722
723 for (i = 0; i < req->n_channels; i++) {
724 if (bands_counted & BIT(req->channels[i]->band))
725 continue;
726 bands_counted |= BIT(req->channels[i]->band);
727 n_bands++;
728 }
729
730 local->hw_scan_ies_bufsize *= n_bands;
731 }
732
733 local->hw_scan_req = kmalloc(
734 sizeof(*local->hw_scan_req) +
735 req->n_channels * sizeof(req->channels[0]) +
736 local->hw_scan_ies_bufsize, GFP_KERNEL);
737 if (!local->hw_scan_req)
738 return -ENOMEM;
739
740 local->hw_scan_req->req.ssids = req->ssids;
741 local->hw_scan_req->req.n_ssids = req->n_ssids;
742 ies = (u8 *)local->hw_scan_req +
743 sizeof(*local->hw_scan_req) +
744 req->n_channels * sizeof(req->channels[0]);
745 local->hw_scan_req->req.ie = ies;
746 local->hw_scan_req->req.flags = req->flags;
747 eth_broadcast_addr(local->hw_scan_req->req.bssid);
748 local->hw_scan_req->req.duration = req->duration;
749 local->hw_scan_req->req.duration_mandatory =
750 req->duration_mandatory;
751
752 local->hw_scan_band = 0;
753 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params;
754 local->hw_scan_req->req.scan_6ghz_params =
755 req->scan_6ghz_params;
756 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz;
757
758 /*
759 * After allocating local->hw_scan_req, we must
760 * go through until ieee80211_prep_hw_scan(), so
761 * anything that might be changed here and leave
762 * this function early must not go after this
763 * allocation.
764 */
765 }
766
767 rcu_assign_pointer(local->scan_req, req);
768 rcu_assign_pointer(local->scan_sdata, sdata);
769
770 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
771 get_random_mask_addr(local->scan_addr,
772 req->mac_addr,
773 req->mac_addr_mask);
774 else
775 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN);
776
777 if (hw_scan) {
778 __set_bit(SCAN_HW_SCANNING, &local->scanning);
779 } else if ((req->n_channels == 1) &&
780 (req->channels[0] == local->_oper_chandef.chan)) {
781 /*
782 * If we are scanning only on the operating channel
783 * then we do not need to stop normal activities
784 */
785 unsigned long next_delay;
786
787 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
788
789 ieee80211_recalc_idle(local);
790
791 /* Notify driver scan is starting, keep order of operations
792 * same as normal software scan, in case that matters. */
793 drv_sw_scan_start(local, sdata, local->scan_addr);
794
795 ieee80211_configure_filter(local); /* accept probe-responses */
796
797 /* We need to ensure power level is at max for scanning. */
798 ieee80211_hw_config(local, 0);
799
800 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR |
801 IEEE80211_CHAN_RADAR)) ||
802 !req->n_ssids) {
803 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
804 if (req->n_ssids)
805 set_bit(SCAN_BEACON_WAIT, &local->scanning);
806 } else {
807 ieee80211_scan_state_send_probe(local, &next_delay);
808 next_delay = IEEE80211_CHANNEL_TIME;
809 }
810
811 /* Now, just wait a bit and we are all done! */
812 ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
813 next_delay);
814 return 0;
815 } else {
816 /* Do normal software scan */
817 __set_bit(SCAN_SW_SCANNING, &local->scanning);
818 }
819
820 ieee80211_recalc_idle(local);
821
822 if (hw_scan) {
823 WARN_ON(!ieee80211_prep_hw_scan(sdata));
824 rc = drv_hw_scan(local, sdata, local->hw_scan_req);
825 } else {
826 rc = ieee80211_start_sw_scan(local, sdata);
827 }
828
829 if (rc) {
830 kfree(local->hw_scan_req);
831 local->hw_scan_req = NULL;
832 local->scanning = 0;
833
834 ieee80211_recalc_idle(local);
835
836 local->scan_req = NULL;
837 RCU_INIT_POINTER(local->scan_sdata, NULL);
838 }
839
840 if (hw_scan && rc == 1) {
841 /*
842 * we can't fall back to software for P2P-GO
843 * as it must update NoA etc.
844 */
845 if (ieee80211_vif_type_p2p(&sdata->vif) ==
846 NL80211_IFTYPE_P2P_GO)
847 return -EOPNOTSUPP;
848 hw_scan = false;
849 goto again;
850 }
851
852 return rc;
853}
854
855static unsigned long
856ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
857{
858 /*
859 * TODO: channel switching also consumes quite some time,
860 * add that delay as well to get a better estimation
861 */
862 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR))
863 return IEEE80211_PASSIVE_CHANNEL_TIME;
864 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
865}
866
867static void ieee80211_scan_state_decision(struct ieee80211_local *local,
868 unsigned long *next_delay)
869{
870 bool associated = false;
871 bool tx_empty = true;
872 bool bad_latency;
873 struct ieee80211_sub_if_data *sdata;
874 struct ieee80211_channel *next_chan;
875 enum mac80211_scan_state next_scan_state;
876 struct cfg80211_scan_request *scan_req;
877
878 /*
879 * check if at least one STA interface is associated,
880 * check if at least one STA interface has pending tx frames
881 * and grab the lowest used beacon interval
882 */
883 mutex_lock(&local->iflist_mtx);
884 list_for_each_entry(sdata, &local->interfaces, list) {
885 if (!ieee80211_sdata_running(sdata))
886 continue;
887
888 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
889 if (sdata->u.mgd.associated) {
890 associated = true;
891
892 if (!qdisc_all_tx_empty(sdata->dev)) {
893 tx_empty = false;
894 break;
895 }
896 }
897 }
898 }
899 mutex_unlock(&local->iflist_mtx);
900
901 scan_req = rcu_dereference_protected(local->scan_req,
902 lockdep_is_held(&local->mtx));
903
904 next_chan = scan_req->channels[local->scan_channel_idx];
905
906 /*
907 * we're currently scanning a different channel, let's
908 * see if we can scan another channel without interfering
909 * with the current traffic situation.
910 *
911 * Keep good latency, do not stay off-channel more than 125 ms.
912 */
913
914 bad_latency = time_after(jiffies +
915 ieee80211_scan_get_channel_time(next_chan),
916 local->leave_oper_channel_time + HZ / 8);
917
918 if (associated && !tx_empty) {
919 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY)
920 next_scan_state = SCAN_ABORT;
921 else
922 next_scan_state = SCAN_SUSPEND;
923 } else if (associated && bad_latency) {
924 next_scan_state = SCAN_SUSPEND;
925 } else {
926 next_scan_state = SCAN_SET_CHANNEL;
927 }
928
929 local->next_scan_state = next_scan_state;
930
931 *next_delay = 0;
932}
933
934static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
935 unsigned long *next_delay)
936{
937 int skip;
938 struct ieee80211_channel *chan;
939 enum nl80211_bss_scan_width oper_scan_width;
940 struct cfg80211_scan_request *scan_req;
941
942 scan_req = rcu_dereference_protected(local->scan_req,
943 lockdep_is_held(&local->mtx));
944
945 skip = 0;
946 chan = scan_req->channels[local->scan_channel_idx];
947
948 local->scan_chandef.chan = chan;
949 local->scan_chandef.center_freq1 = chan->center_freq;
950 local->scan_chandef.freq1_offset = chan->freq_offset;
951 local->scan_chandef.center_freq2 = 0;
952
953 /* For scanning on the S1G band, ignore scan_width (which is constant
954 * across all channels) for now since channel width is specific to each
955 * channel. Detect the required channel width here and likely revisit
956 * later. Maybe scan_width could be used to build the channel scan list?
957 */
958 if (chan->band == NL80211_BAND_S1GHZ) {
959 local->scan_chandef.width = ieee80211_s1g_channel_width(chan);
960 goto set_channel;
961 }
962
963 switch (scan_req->scan_width) {
964 case NL80211_BSS_CHAN_WIDTH_5:
965 local->scan_chandef.width = NL80211_CHAN_WIDTH_5;
966 break;
967 case NL80211_BSS_CHAN_WIDTH_10:
968 local->scan_chandef.width = NL80211_CHAN_WIDTH_10;
969 break;
970 default:
971 case NL80211_BSS_CHAN_WIDTH_20:
972 /* If scanning on oper channel, use whatever channel-type
973 * is currently in use.
974 */
975 oper_scan_width = cfg80211_chandef_to_scan_width(
976 &local->_oper_chandef);
977 if (chan == local->_oper_chandef.chan &&
978 oper_scan_width == scan_req->scan_width)
979 local->scan_chandef = local->_oper_chandef;
980 else
981 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
982 break;
983 case NL80211_BSS_CHAN_WIDTH_1:
984 case NL80211_BSS_CHAN_WIDTH_2:
985 /* shouldn't get here, S1G handled above */
986 WARN_ON(1);
987 break;
988 }
989
990set_channel:
991 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL))
992 skip = 1;
993
994 /* advance state machine to next channel/band */
995 local->scan_channel_idx++;
996
997 if (skip) {
998 /* if we skip this channel return to the decision state */
999 local->next_scan_state = SCAN_DECISION;
1000 return;
1001 }
1002
1003 /*
1004 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
1005 * (which unfortunately doesn't say _why_ step a) is done,
1006 * but it waits for the probe delay or until a frame is
1007 * received - and the received frame would update the NAV).
1008 * For now, we do not support waiting until a frame is
1009 * received.
1010 *
1011 * In any case, it is not necessary for a passive scan.
1012 */
1013 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) ||
1014 !scan_req->n_ssids) {
1015 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
1016 local->next_scan_state = SCAN_DECISION;
1017 if (scan_req->n_ssids)
1018 set_bit(SCAN_BEACON_WAIT, &local->scanning);
1019 return;
1020 }
1021
1022 /* active scan, send probes */
1023 *next_delay = IEEE80211_PROBE_DELAY;
1024 local->next_scan_state = SCAN_SEND_PROBE;
1025}
1026
1027static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
1028 unsigned long *next_delay)
1029{
1030 /* switch back to the operating channel */
1031 local->scan_chandef.chan = NULL;
1032 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
1033
1034 /* disable PS */
1035 ieee80211_offchannel_return(local);
1036
1037 *next_delay = HZ / 5;
1038 /* afterwards, resume scan & go to next channel */
1039 local->next_scan_state = SCAN_RESUME;
1040}
1041
1042static void ieee80211_scan_state_resume(struct ieee80211_local *local,
1043 unsigned long *next_delay)
1044{
1045 ieee80211_offchannel_stop_vifs(local);
1046
1047 if (local->ops->flush) {
1048 ieee80211_flush_queues(local, NULL, false);
1049 *next_delay = 0;
1050 } else
1051 *next_delay = HZ / 10;
1052
1053 /* remember when we left the operating channel */
1054 local->leave_oper_channel_time = jiffies;
1055
1056 /* advance to the next channel to be scanned */
1057 local->next_scan_state = SCAN_SET_CHANNEL;
1058}
1059
1060void ieee80211_scan_work(struct work_struct *work)
1061{
1062 struct ieee80211_local *local =
1063 container_of(work, struct ieee80211_local, scan_work.work);
1064 struct ieee80211_sub_if_data *sdata;
1065 struct cfg80211_scan_request *scan_req;
1066 unsigned long next_delay = 0;
1067 bool aborted;
1068
1069 mutex_lock(&local->mtx);
1070
1071 if (!ieee80211_can_run_worker(local)) {
1072 aborted = true;
1073 goto out_complete;
1074 }
1075
1076 sdata = rcu_dereference_protected(local->scan_sdata,
1077 lockdep_is_held(&local->mtx));
1078 scan_req = rcu_dereference_protected(local->scan_req,
1079 lockdep_is_held(&local->mtx));
1080
1081 /* When scanning on-channel, the first-callback means completed. */
1082 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) {
1083 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
1084 goto out_complete;
1085 }
1086
1087 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) {
1088 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
1089 goto out_complete;
1090 }
1091
1092 if (!sdata || !scan_req)
1093 goto out;
1094
1095 if (!local->scanning) {
1096 int rc;
1097
1098 RCU_INIT_POINTER(local->scan_req, NULL);
1099 RCU_INIT_POINTER(local->scan_sdata, NULL);
1100
1101 rc = __ieee80211_start_scan(sdata, scan_req);
1102 if (rc) {
1103 /* need to complete scan in cfg80211 */
1104 rcu_assign_pointer(local->scan_req, scan_req);
1105 aborted = true;
1106 goto out_complete;
1107 } else
1108 goto out;
1109 }
1110
1111 clear_bit(SCAN_BEACON_WAIT, &local->scanning);
1112
1113 /*
1114 * as long as no delay is required advance immediately
1115 * without scheduling a new work
1116 */
1117 do {
1118 if (!ieee80211_sdata_running(sdata)) {
1119 aborted = true;
1120 goto out_complete;
1121 }
1122
1123 if (test_and_clear_bit(SCAN_BEACON_DONE, &local->scanning) &&
1124 local->next_scan_state == SCAN_DECISION)
1125 local->next_scan_state = SCAN_SEND_PROBE;
1126
1127 switch (local->next_scan_state) {
1128 case SCAN_DECISION:
1129 /* if no more bands/channels left, complete scan */
1130 if (local->scan_channel_idx >= scan_req->n_channels) {
1131 aborted = false;
1132 goto out_complete;
1133 }
1134 ieee80211_scan_state_decision(local, &next_delay);
1135 break;
1136 case SCAN_SET_CHANNEL:
1137 ieee80211_scan_state_set_channel(local, &next_delay);
1138 break;
1139 case SCAN_SEND_PROBE:
1140 ieee80211_scan_state_send_probe(local, &next_delay);
1141 break;
1142 case SCAN_SUSPEND:
1143 ieee80211_scan_state_suspend(local, &next_delay);
1144 break;
1145 case SCAN_RESUME:
1146 ieee80211_scan_state_resume(local, &next_delay);
1147 break;
1148 case SCAN_ABORT:
1149 aborted = true;
1150 goto out_complete;
1151 }
1152 } while (next_delay == 0);
1153
1154 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay);
1155 goto out;
1156
1157out_complete:
1158 __ieee80211_scan_completed(&local->hw, aborted);
1159out:
1160 mutex_unlock(&local->mtx);
1161}
1162
1163int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
1164 struct cfg80211_scan_request *req)
1165{
1166 int res;
1167
1168 mutex_lock(&sdata->local->mtx);
1169 res = __ieee80211_start_scan(sdata, req);
1170 mutex_unlock(&sdata->local->mtx);
1171
1172 return res;
1173}
1174
1175int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
1176 const u8 *ssid, u8 ssid_len,
1177 struct ieee80211_channel **channels,
1178 unsigned int n_channels,
1179 enum nl80211_bss_scan_width scan_width)
1180{
1181 struct ieee80211_local *local = sdata->local;
1182 int ret = -EBUSY, i, n_ch = 0;
1183 enum nl80211_band band;
1184
1185 mutex_lock(&local->mtx);
1186
1187 /* busy scanning */
1188 if (local->scan_req)
1189 goto unlock;
1190
1191 /* fill internal scan request */
1192 if (!channels) {
1193 int max_n;
1194
1195 for (band = 0; band < NUM_NL80211_BANDS; band++) {
1196 if (!local->hw.wiphy->bands[band] ||
1197 band == NL80211_BAND_6GHZ)
1198 continue;
1199
1200 max_n = local->hw.wiphy->bands[band]->n_channels;
1201 for (i = 0; i < max_n; i++) {
1202 struct ieee80211_channel *tmp_ch =
1203 &local->hw.wiphy->bands[band]->channels[i];
1204
1205 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR |
1206 IEEE80211_CHAN_DISABLED))
1207 continue;
1208
1209 local->int_scan_req->channels[n_ch] = tmp_ch;
1210 n_ch++;
1211 }
1212 }
1213
1214 if (WARN_ON_ONCE(n_ch == 0))
1215 goto unlock;
1216
1217 local->int_scan_req->n_channels = n_ch;
1218 } else {
1219 for (i = 0; i < n_channels; i++) {
1220 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR |
1221 IEEE80211_CHAN_DISABLED))
1222 continue;
1223
1224 local->int_scan_req->channels[n_ch] = channels[i];
1225 n_ch++;
1226 }
1227
1228 if (WARN_ON_ONCE(n_ch == 0))
1229 goto unlock;
1230
1231 local->int_scan_req->n_channels = n_ch;
1232 }
1233
1234 local->int_scan_req->ssids = &local->scan_ssid;
1235 local->int_scan_req->n_ssids = 1;
1236 local->int_scan_req->scan_width = scan_width;
1237 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
1238 local->int_scan_req->ssids[0].ssid_len = ssid_len;
1239
1240 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
1241 unlock:
1242 mutex_unlock(&local->mtx);
1243 return ret;
1244}
1245
1246/*
1247 * Only call this function when a scan can't be queued -- under RTNL.
1248 */
1249void ieee80211_scan_cancel(struct ieee80211_local *local)
1250{
1251 /*
1252 * We are canceling software scan, or deferred scan that was not
1253 * yet really started (see __ieee80211_start_scan ).
1254 *
1255 * Regarding hardware scan:
1256 * - we can not call __ieee80211_scan_completed() as when
1257 * SCAN_HW_SCANNING bit is set this function change
1258 * local->hw_scan_req to operate on 5G band, what race with
1259 * driver which can use local->hw_scan_req
1260 *
1261 * - we can not cancel scan_work since driver can schedule it
1262 * by ieee80211_scan_completed(..., true) to finish scan
1263 *
1264 * Hence we only call the cancel_hw_scan() callback, but the low-level
1265 * driver is still responsible for calling ieee80211_scan_completed()
1266 * after the scan was completed/aborted.
1267 */
1268
1269 mutex_lock(&local->mtx);
1270 if (!local->scan_req)
1271 goto out;
1272
1273 /*
1274 * We have a scan running and the driver already reported completion,
1275 * but the worker hasn't run yet or is stuck on the mutex - mark it as
1276 * cancelled.
1277 */
1278 if (test_bit(SCAN_HW_SCANNING, &local->scanning) &&
1279 test_bit(SCAN_COMPLETED, &local->scanning)) {
1280 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1281 goto out;
1282 }
1283
1284 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
1285 /*
1286 * Make sure that __ieee80211_scan_completed doesn't trigger a
1287 * scan on another band.
1288 */
1289 set_bit(SCAN_HW_CANCELLED, &local->scanning);
1290 if (local->ops->cancel_hw_scan)
1291 drv_cancel_hw_scan(local,
1292 rcu_dereference_protected(local->scan_sdata,
1293 lockdep_is_held(&local->mtx)));
1294 goto out;
1295 }
1296
1297 /*
1298 * If the work is currently running, it must be blocked on
1299 * the mutex, but we'll set scan_sdata = NULL and it'll
1300 * simply exit once it acquires the mutex.
1301 */
1302 cancel_delayed_work(&local->scan_work);
1303 /* and clean up */
1304 memset(&local->scan_info, 0, sizeof(local->scan_info));
1305 __ieee80211_scan_completed(&local->hw, true);
1306out:
1307 mutex_unlock(&local->mtx);
1308}
1309
1310int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1311 struct cfg80211_sched_scan_request *req)
1312{
1313 struct ieee80211_local *local = sdata->local;
1314 struct ieee80211_scan_ies sched_scan_ies = {};
1315 struct cfg80211_chan_def chandef;
1316 int ret, i, iebufsz, num_bands = 0;
1317 u32 rate_masks[NUM_NL80211_BANDS] = {};
1318 u8 bands_used = 0;
1319 u8 *ie;
1320 u32 flags = 0;
1321
1322 iebufsz = local->scan_ies_len + req->ie_len;
1323
1324 lockdep_assert_held(&local->mtx);
1325
1326 if (!local->ops->sched_scan_start)
1327 return -ENOTSUPP;
1328
1329 for (i = 0; i < NUM_NL80211_BANDS; i++) {
1330 if (local->hw.wiphy->bands[i]) {
1331 bands_used |= BIT(i);
1332 rate_masks[i] = (u32) -1;
1333 num_bands++;
1334 }
1335 }
1336
1337 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
1338 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
1339
1340 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL);
1341 if (!ie) {
1342 ret = -ENOMEM;
1343 goto out;
1344 }
1345
1346 ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
1347
1348 ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz,
1349 &sched_scan_ies, req->ie,
1350 req->ie_len, bands_used, rate_masks, &chandef,
1351 flags);
1352
1353 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
1354 if (ret == 0) {
1355 rcu_assign_pointer(local->sched_scan_sdata, sdata);
1356 rcu_assign_pointer(local->sched_scan_req, req);
1357 }
1358
1359 kfree(ie);
1360
1361out:
1362 if (ret) {
1363 /* Clean in case of failure after HW restart or upon resume. */
1364 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1365 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1366 }
1367
1368 return ret;
1369}
1370
1371int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
1372 struct cfg80211_sched_scan_request *req)
1373{
1374 struct ieee80211_local *local = sdata->local;
1375 int ret;
1376
1377 mutex_lock(&local->mtx);
1378
1379 if (rcu_access_pointer(local->sched_scan_sdata)) {
1380 mutex_unlock(&local->mtx);
1381 return -EBUSY;
1382 }
1383
1384 ret = __ieee80211_request_sched_scan_start(sdata, req);
1385
1386 mutex_unlock(&local->mtx);
1387 return ret;
1388}
1389
1390int 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 mutex_lock(&local->mtx);
1396
1397 if (!local->ops->sched_scan_stop) {
1398 ret = -ENOTSUPP;
1399 goto out;
1400 }
1401
1402 /* We don't want to restart sched scan anymore. */
1403 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1404
1405 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata,
1406 lockdep_is_held(&local->mtx));
1407 if (sched_scan_sdata) {
1408 ret = drv_sched_scan_stop(local, sched_scan_sdata);
1409 if (!ret)
1410 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1411 }
1412out:
1413 mutex_unlock(&local->mtx);
1414
1415 return ret;
1416}
1417
1418void ieee80211_sched_scan_results(struct ieee80211_hw *hw)
1419{
1420 struct ieee80211_local *local = hw_to_local(hw);
1421
1422 trace_api_sched_scan_results(local);
1423
1424 cfg80211_sched_scan_results(hw->wiphy, 0);
1425}
1426EXPORT_SYMBOL(ieee80211_sched_scan_results);
1427
1428void ieee80211_sched_scan_end(struct ieee80211_local *local)
1429{
1430 mutex_lock(&local->mtx);
1431
1432 if (!rcu_access_pointer(local->sched_scan_sdata)) {
1433 mutex_unlock(&local->mtx);
1434 return;
1435 }
1436
1437 RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
1438
1439 /* If sched scan was aborted by the driver. */
1440 RCU_INIT_POINTER(local->sched_scan_req, NULL);
1441
1442 mutex_unlock(&local->mtx);
1443
1444 cfg80211_sched_scan_stopped(local->hw.wiphy, 0);
1445}
1446
1447void ieee80211_sched_scan_stopped_work(struct work_struct *work)
1448{
1449 struct ieee80211_local *local =
1450 container_of(work, struct ieee80211_local,
1451 sched_scan_stopped_work);
1452
1453 ieee80211_sched_scan_end(local);
1454}
1455
1456void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
1457{
1458 struct ieee80211_local *local = hw_to_local(hw);
1459
1460 trace_api_sched_scan_stopped(local);
1461
1462 /*
1463 * this shouldn't really happen, so for simplicity
1464 * simply ignore it, and let mac80211 reconfigure
1465 * the sched scan later on.
1466 */
1467 if (local->in_reconfig)
1468 return;
1469
1470 schedule_work(&local->sched_scan_stopped_work);
1471}
1472EXPORT_SYMBOL(ieee80211_sched_scan_stopped);