1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Scanning implementation 4 * 5 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi> 6 * Copyright 2004, Instant802 Networks, Inc. 7 * Copyright 2005, Devicescape Software, Inc. 8 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> 9 * Copyright 2007, Michael Wu <flamingice@sourmilk.net> 10 * Copyright 2013-2015 Intel Mobile Communications GmbH 11 * Copyright 2016-2017 Intel Deutschland GmbH 12 * Copyright (C) 2018-2025 Intel Corporation 13 */ 14 15 #include <linux/if_arp.h> 16 #include <linux/etherdevice.h> 17 #include <linux/rtnetlink.h> 18 #include <net/sch_generic.h> 19 #include <linux/slab.h> 20 #include <linux/export.h> 21 #include <linux/random.h> 22 #include <net/mac80211.h> 23 24 #include "ieee80211_i.h" 25 #include "driver-ops.h" 26 #include "mesh.h" 27 28 #define IEEE80211_PROBE_DELAY (HZ / 33) 29 #define IEEE80211_CHANNEL_TIME (HZ / 33) 30 #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 9) 31 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 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 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 * 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 } 238 239 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 } 272 273 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 } 361 362 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 */ 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 } 438 439 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 } 530 531 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); 547 548 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 } 588 589 static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata, 590 struct cfg80211_scan_request *req) 591 { 592 struct ieee80211_local *local = sdata->local; 593 struct ieee80211_sub_if_data *sdata_iter; 594 unsigned int link_id; 595 596 lockdep_assert_wiphy(local->hw.wiphy); 597 598 if (!ieee80211_is_radar_required(local, req)) 599 return true; 600 601 if (!regulatory_pre_cac_allowed(local->hw.wiphy)) 602 return false; 603 604 list_for_each_entry(sdata_iter, &local->interfaces, list) { 605 for_each_valid_link(&sdata_iter->wdev, link_id) 606 if (sdata_iter->wdev.links[link_id].cac_started) 607 return false; 608 } 609 610 return true; 611 } 612 613 static bool ieee80211_can_scan(struct ieee80211_local *local, 614 struct ieee80211_sub_if_data *sdata, 615 struct cfg80211_scan_request *req) 616 { 617 if (!__ieee80211_can_leave_ch(sdata, req)) 618 return false; 619 620 if (!list_empty(&local->roc_list)) 621 return false; 622 623 if (sdata->vif.type == NL80211_IFTYPE_STATION && 624 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL) 625 return false; 626 627 return true; 628 } 629 630 void ieee80211_run_deferred_scan(struct ieee80211_local *local) 631 { 632 struct cfg80211_scan_request *req; 633 634 lockdep_assert_wiphy(local->hw.wiphy); 635 636 if (!local->scan_req || local->scanning) 637 return; 638 639 req = wiphy_dereference(local->hw.wiphy, local->scan_req); 640 if (!ieee80211_can_scan(local, 641 rcu_dereference_protected( 642 local->scan_sdata, 643 lockdep_is_held(&local->hw.wiphy->mtx)), 644 req)) 645 return; 646 647 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 648 round_jiffies_relative(0)); 649 } 650 651 static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata, 652 const u8 *src, const u8 *dst, 653 const u8 *ssid, size_t ssid_len, 654 const u8 *ie, size_t ie_len, 655 u32 ratemask, u32 flags, u32 tx_flags, 656 struct ieee80211_channel *channel) 657 { 658 struct sk_buff *skb; 659 660 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel, 661 ssid, ssid_len, 662 ie, ie_len, flags); 663 664 if (skb) { 665 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) { 666 struct ieee80211_hdr *hdr = (void *)skb->data; 667 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 668 u16 sn = get_random_u16(); 669 670 info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO; 671 hdr->seq_ctrl = 672 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn)); 673 } 674 IEEE80211_SKB_CB(skb)->flags |= tx_flags; 675 IEEE80211_SKB_CB(skb)->control.flags |= IEEE80211_TX_CTRL_DONT_USE_RATE_MASK; 676 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band); 677 } 678 } 679 680 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, 681 unsigned long *next_delay) 682 { 683 int i; 684 struct ieee80211_sub_if_data *sdata; 685 struct cfg80211_scan_request *scan_req; 686 enum nl80211_band band = local->hw.conf.chandef.chan->band; 687 u32 flags = 0, tx_flags; 688 689 scan_req = rcu_dereference_protected(local->scan_req, 690 lockdep_is_held(&local->hw.wiphy->mtx)); 691 692 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK; 693 if (scan_req->no_cck) 694 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE; 695 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 696 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 697 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN) 698 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN; 699 700 sdata = rcu_dereference_protected(local->scan_sdata, 701 lockdep_is_held(&local->hw.wiphy->mtx)); 702 703 for (i = 0; i < scan_req->n_ssids; i++) 704 ieee80211_send_scan_probe_req( 705 sdata, local->scan_addr, scan_req->bssid, 706 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len, 707 scan_req->ie, scan_req->ie_len, 708 scan_req->rates[band], flags, 709 tx_flags, local->hw.conf.chandef.chan); 710 711 /* 712 * After sending probe requests, wait for probe responses 713 * on the channel. 714 */ 715 *next_delay = msecs_to_jiffies(scan_req->duration) > 716 IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME ? 717 msecs_to_jiffies(scan_req->duration) - IEEE80211_PROBE_DELAY : 718 IEEE80211_CHANNEL_TIME; 719 local->next_scan_state = SCAN_DECISION; 720 } 721 722 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, 723 struct cfg80211_scan_request *req) 724 { 725 struct ieee80211_local *local = sdata->local; 726 bool hw_scan = local->ops->hw_scan; 727 int rc; 728 729 lockdep_assert_wiphy(local->hw.wiphy); 730 731 if (local->scan_req) 732 return -EBUSY; 733 734 /* For an MLO connection, if a link ID was specified, validate that it 735 * is indeed active. 736 */ 737 if (ieee80211_vif_is_mld(&sdata->vif) && req->tsf_report_link_id >= 0 && 738 !(sdata->vif.active_links & BIT(req->tsf_report_link_id))) 739 return -EINVAL; 740 741 if (!__ieee80211_can_leave_ch(sdata, req)) 742 return -EBUSY; 743 744 if (!ieee80211_can_scan(local, sdata, req)) { 745 /* wait for the work to finish/time out */ 746 rcu_assign_pointer(local->scan_req, req); 747 rcu_assign_pointer(local->scan_sdata, sdata); 748 return 0; 749 } 750 751 again: 752 if (hw_scan) { 753 u8 *ies; 754 755 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len; 756 757 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 758 int i, n_bands = 0; 759 u8 bands_counted = 0; 760 761 for (i = 0; i < req->n_channels; i++) { 762 if (bands_counted & BIT(req->channels[i]->band)) 763 continue; 764 bands_counted |= BIT(req->channels[i]->band); 765 n_bands++; 766 } 767 768 local->hw_scan_ies_bufsize *= n_bands; 769 } 770 771 local->hw_scan_req = kmalloc(struct_size(local->hw_scan_req, 772 req.channels, 773 req->n_channels) + 774 local->hw_scan_ies_bufsize, 775 GFP_KERNEL); 776 if (!local->hw_scan_req) 777 return -ENOMEM; 778 779 local->hw_scan_req->req.ssids = req->ssids; 780 local->hw_scan_req->req.n_ssids = req->n_ssids; 781 /* None of the channels are actually set 782 * up but let UBSAN know the boundaries. 783 */ 784 local->hw_scan_req->req.n_channels = req->n_channels; 785 786 ies = (u8 *)local->hw_scan_req + 787 sizeof(*local->hw_scan_req) + 788 req->n_channels * sizeof(req->channels[0]); 789 local->hw_scan_req->req.ie = ies; 790 local->hw_scan_req->req.flags = req->flags; 791 eth_broadcast_addr(local->hw_scan_req->req.bssid); 792 local->hw_scan_req->req.duration = req->duration; 793 local->hw_scan_req->req.duration_mandatory = 794 req->duration_mandatory; 795 local->hw_scan_req->req.tsf_report_link_id = 796 req->tsf_report_link_id; 797 798 local->hw_scan_band = 0; 799 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params; 800 local->hw_scan_req->req.scan_6ghz_params = 801 req->scan_6ghz_params; 802 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz; 803 local->hw_scan_req->req.first_part = req->first_part; 804 805 /* 806 * After allocating local->hw_scan_req, we must 807 * go through until ieee80211_prep_hw_scan(), so 808 * anything that might be changed here and leave 809 * this function early must not go after this 810 * allocation. 811 */ 812 } 813 814 rcu_assign_pointer(local->scan_req, req); 815 rcu_assign_pointer(local->scan_sdata, sdata); 816 817 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 818 get_random_mask_addr(local->scan_addr, 819 req->mac_addr, 820 req->mac_addr_mask); 821 else 822 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN); 823 824 if (hw_scan) { 825 __set_bit(SCAN_HW_SCANNING, &local->scanning); 826 } else if ((req->n_channels == 1) && 827 (req->channels[0] == local->hw.conf.chandef.chan)) { 828 /* 829 * If we are scanning only on the operating channel 830 * then we do not need to stop normal activities 831 */ 832 unsigned long next_delay; 833 834 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning); 835 836 ieee80211_recalc_idle(local); 837 838 /* Notify driver scan is starting, keep order of operations 839 * same as normal software scan, in case that matters. */ 840 drv_sw_scan_start(local, sdata, local->scan_addr); 841 842 ieee80211_configure_filter(local); /* accept probe-responses */ 843 844 /* We need to ensure power level is at max for scanning. */ 845 ieee80211_hw_conf_chan(local); 846 847 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR | 848 IEEE80211_CHAN_RADAR)) || 849 !req->n_ssids) { 850 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 851 if (req->n_ssids) 852 set_bit(SCAN_BEACON_WAIT, &local->scanning); 853 } else { 854 ieee80211_scan_state_send_probe(local, &next_delay); 855 next_delay = IEEE80211_CHANNEL_TIME; 856 } 857 858 /* Now, just wait a bit and we are all done! */ 859 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 860 next_delay); 861 return 0; 862 } else { 863 /* Do normal software scan */ 864 __set_bit(SCAN_SW_SCANNING, &local->scanning); 865 } 866 867 ieee80211_recalc_idle(local); 868 869 if (hw_scan) { 870 WARN_ON(!ieee80211_prep_hw_scan(sdata)); 871 rc = drv_hw_scan(local, sdata, local->hw_scan_req); 872 } else { 873 rc = ieee80211_start_sw_scan(local, sdata); 874 } 875 876 if (rc) { 877 kfree(local->hw_scan_req); 878 local->hw_scan_req = NULL; 879 local->scanning = 0; 880 881 ieee80211_recalc_idle(local); 882 883 local->scan_req = NULL; 884 RCU_INIT_POINTER(local->scan_sdata, NULL); 885 } 886 887 if (hw_scan && rc == 1) { 888 /* 889 * we can't fall back to software for P2P-GO 890 * as it must update NoA etc. 891 */ 892 if (ieee80211_vif_type_p2p(&sdata->vif) == 893 NL80211_IFTYPE_P2P_GO) 894 return -EOPNOTSUPP; 895 hw_scan = false; 896 goto again; 897 } 898 899 return rc; 900 } 901 902 static unsigned long 903 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) 904 { 905 /* 906 * TODO: channel switching also consumes quite some time, 907 * add that delay as well to get a better estimation 908 */ 909 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) 910 return IEEE80211_PASSIVE_CHANNEL_TIME; 911 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; 912 } 913 914 static void ieee80211_scan_state_decision(struct ieee80211_local *local, 915 unsigned long *next_delay) 916 { 917 bool associated = false; 918 bool tx_empty = true; 919 bool bad_latency; 920 struct ieee80211_sub_if_data *sdata; 921 struct ieee80211_channel *next_chan; 922 enum mac80211_scan_state next_scan_state; 923 struct cfg80211_scan_request *scan_req; 924 925 lockdep_assert_wiphy(local->hw.wiphy); 926 927 /* 928 * check if at least one STA interface is associated, 929 * check if at least one STA interface has pending tx frames 930 * and grab the lowest used beacon interval 931 */ 932 list_for_each_entry(sdata, &local->interfaces, list) { 933 if (!ieee80211_sdata_running(sdata)) 934 continue; 935 936 if (sdata->vif.type == NL80211_IFTYPE_STATION) { 937 if (sdata->u.mgd.associated) { 938 associated = true; 939 940 if (!qdisc_all_tx_empty(sdata->dev)) { 941 tx_empty = false; 942 break; 943 } 944 } 945 } 946 } 947 948 scan_req = rcu_dereference_protected(local->scan_req, 949 lockdep_is_held(&local->hw.wiphy->mtx)); 950 951 next_chan = scan_req->channels[local->scan_channel_idx]; 952 953 /* 954 * we're currently scanning a different channel, let's 955 * see if we can scan another channel without interfering 956 * with the current traffic situation. 957 * 958 * Keep good latency, do not stay off-channel more than 125 ms. 959 */ 960 961 bad_latency = time_after(jiffies + 962 ieee80211_scan_get_channel_time(next_chan), 963 local->leave_oper_channel_time + HZ / 8); 964 965 if (associated && !tx_empty) { 966 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY) 967 next_scan_state = SCAN_ABORT; 968 else 969 next_scan_state = SCAN_SUSPEND; 970 } else if (associated && bad_latency) { 971 next_scan_state = SCAN_SUSPEND; 972 } else { 973 next_scan_state = SCAN_SET_CHANNEL; 974 } 975 976 local->next_scan_state = next_scan_state; 977 978 *next_delay = 0; 979 } 980 981 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, 982 unsigned long *next_delay) 983 { 984 int skip; 985 struct ieee80211_channel *chan; 986 struct cfg80211_scan_request *scan_req; 987 988 scan_req = rcu_dereference_protected(local->scan_req, 989 lockdep_is_held(&local->hw.wiphy->mtx)); 990 991 skip = 0; 992 chan = scan_req->channels[local->scan_channel_idx]; 993 994 local->scan_chandef.chan = chan; 995 local->scan_chandef.center_freq1 = chan->center_freq; 996 local->scan_chandef.freq1_offset = chan->freq_offset; 997 local->scan_chandef.center_freq2 = 0; 998 999 /* For scanning on the S1G band, detect the channel width according to 1000 * the channel being scanned. 1001 */ 1002 if (chan->band == NL80211_BAND_S1GHZ) { 1003 local->scan_chandef.width = ieee80211_s1g_channel_width(chan); 1004 goto set_channel; 1005 } 1006 1007 /* If scanning on oper channel, use whatever channel-type 1008 * is currently in use. 1009 */ 1010 if (chan == local->hw.conf.chandef.chan) 1011 local->scan_chandef = local->hw.conf.chandef; 1012 else 1013 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT; 1014 1015 set_channel: 1016 if (ieee80211_hw_conf_chan(local)) 1017 skip = 1; 1018 1019 /* advance state machine to next channel/band */ 1020 local->scan_channel_idx++; 1021 1022 if (skip) { 1023 /* if we skip this channel return to the decision state */ 1024 local->next_scan_state = SCAN_DECISION; 1025 return; 1026 } 1027 1028 /* 1029 * Probe delay is used to update the NAV, cf. 11.1.3.2.2 1030 * (which unfortunately doesn't say _why_ step a) is done, 1031 * but it waits for the probe delay or until a frame is 1032 * received - and the received frame would update the NAV). 1033 * For now, we do not support waiting until a frame is 1034 * received. 1035 * 1036 * In any case, it is not necessary for a passive scan. 1037 */ 1038 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) || 1039 !scan_req->n_ssids) { 1040 *next_delay = max(msecs_to_jiffies(scan_req->duration), 1041 IEEE80211_PASSIVE_CHANNEL_TIME); 1042 local->next_scan_state = SCAN_DECISION; 1043 if (scan_req->n_ssids) 1044 set_bit(SCAN_BEACON_WAIT, &local->scanning); 1045 return; 1046 } 1047 1048 /* active scan, send probes */ 1049 *next_delay = IEEE80211_PROBE_DELAY; 1050 local->next_scan_state = SCAN_SEND_PROBE; 1051 } 1052 1053 static void ieee80211_scan_state_suspend(struct ieee80211_local *local, 1054 unsigned long *next_delay) 1055 { 1056 /* switch back to the operating channel */ 1057 local->scan_chandef.chan = NULL; 1058 ieee80211_hw_conf_chan(local); 1059 1060 /* disable PS */ 1061 ieee80211_offchannel_return(local); 1062 1063 *next_delay = HZ / 5; 1064 /* afterwards, resume scan & go to next channel */ 1065 local->next_scan_state = SCAN_RESUME; 1066 } 1067 1068 static void ieee80211_scan_state_resume(struct ieee80211_local *local, 1069 unsigned long *next_delay) 1070 { 1071 ieee80211_offchannel_stop_vifs(local); 1072 1073 if (local->ops->flush) { 1074 ieee80211_flush_queues(local, NULL, false); 1075 *next_delay = 0; 1076 } else 1077 *next_delay = HZ / 10; 1078 1079 /* remember when we left the operating channel */ 1080 local->leave_oper_channel_time = jiffies; 1081 1082 /* advance to the next channel to be scanned */ 1083 local->next_scan_state = SCAN_SET_CHANNEL; 1084 } 1085 1086 void ieee80211_scan_work(struct wiphy *wiphy, struct wiphy_work *work) 1087 { 1088 struct ieee80211_local *local = 1089 container_of(work, struct ieee80211_local, scan_work.work); 1090 struct ieee80211_sub_if_data *sdata; 1091 struct cfg80211_scan_request *scan_req; 1092 unsigned long next_delay = 0; 1093 bool aborted; 1094 1095 lockdep_assert_wiphy(local->hw.wiphy); 1096 1097 if (!ieee80211_can_run_worker(local)) { 1098 aborted = true; 1099 goto out_complete; 1100 } 1101 1102 sdata = rcu_dereference_protected(local->scan_sdata, 1103 lockdep_is_held(&local->hw.wiphy->mtx)); 1104 scan_req = rcu_dereference_protected(local->scan_req, 1105 lockdep_is_held(&local->hw.wiphy->mtx)); 1106 1107 /* When scanning on-channel, the first-callback means completed. */ 1108 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) { 1109 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1110 goto out_complete; 1111 } 1112 1113 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) { 1114 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1115 goto out_complete; 1116 } 1117 1118 if (!sdata || !scan_req) 1119 return; 1120 1121 if (!local->scanning) { 1122 int rc; 1123 1124 RCU_INIT_POINTER(local->scan_req, NULL); 1125 RCU_INIT_POINTER(local->scan_sdata, NULL); 1126 1127 rc = __ieee80211_start_scan(sdata, scan_req); 1128 if (!rc) 1129 return; 1130 /* need to complete scan in cfg80211 */ 1131 rcu_assign_pointer(local->scan_req, scan_req); 1132 aborted = true; 1133 goto out_complete; 1134 } 1135 1136 clear_bit(SCAN_BEACON_WAIT, &local->scanning); 1137 1138 /* 1139 * as long as no delay is required advance immediately 1140 * without scheduling a new work 1141 */ 1142 do { 1143 if (!ieee80211_sdata_running(sdata)) { 1144 aborted = true; 1145 goto out_complete; 1146 } 1147 1148 if (test_and_clear_bit(SCAN_BEACON_DONE, &local->scanning) && 1149 local->next_scan_state == SCAN_DECISION) 1150 local->next_scan_state = SCAN_SEND_PROBE; 1151 1152 switch (local->next_scan_state) { 1153 case SCAN_DECISION: 1154 /* if no more bands/channels left, complete scan */ 1155 if (local->scan_channel_idx >= scan_req->n_channels) { 1156 aborted = false; 1157 goto out_complete; 1158 } 1159 ieee80211_scan_state_decision(local, &next_delay); 1160 break; 1161 case SCAN_SET_CHANNEL: 1162 ieee80211_scan_state_set_channel(local, &next_delay); 1163 break; 1164 case SCAN_SEND_PROBE: 1165 ieee80211_scan_state_send_probe(local, &next_delay); 1166 break; 1167 case SCAN_SUSPEND: 1168 ieee80211_scan_state_suspend(local, &next_delay); 1169 break; 1170 case SCAN_RESUME: 1171 ieee80211_scan_state_resume(local, &next_delay); 1172 break; 1173 case SCAN_ABORT: 1174 aborted = true; 1175 goto out_complete; 1176 } 1177 } while (next_delay == 0); 1178 1179 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 1180 next_delay); 1181 return; 1182 1183 out_complete: 1184 __ieee80211_scan_completed(&local->hw, aborted); 1185 } 1186 1187 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, 1188 struct cfg80211_scan_request *req) 1189 { 1190 lockdep_assert_wiphy(sdata->local->hw.wiphy); 1191 1192 return __ieee80211_start_scan(sdata, req); 1193 } 1194 1195 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata, 1196 const u8 *ssid, u8 ssid_len, 1197 struct ieee80211_channel **channels, 1198 unsigned int n_channels) 1199 { 1200 struct ieee80211_local *local = sdata->local; 1201 int i, n_ch = 0; 1202 enum nl80211_band band; 1203 1204 lockdep_assert_wiphy(local->hw.wiphy); 1205 1206 /* busy scanning */ 1207 if (local->scan_req) 1208 return -EBUSY; 1209 1210 /* fill internal scan request */ 1211 if (!channels) { 1212 int max_n; 1213 1214 for (band = 0; band < NUM_NL80211_BANDS; band++) { 1215 if (!local->hw.wiphy->bands[band] || 1216 band == NL80211_BAND_6GHZ) 1217 continue; 1218 1219 max_n = local->hw.wiphy->bands[band]->n_channels; 1220 for (i = 0; i < max_n; i++) { 1221 struct ieee80211_channel *tmp_ch = 1222 &local->hw.wiphy->bands[band]->channels[i]; 1223 1224 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR | 1225 IEEE80211_CHAN_DISABLED) || 1226 !cfg80211_wdev_channel_allowed(&sdata->wdev, 1227 tmp_ch)) 1228 continue; 1229 1230 local->int_scan_req->channels[n_ch] = tmp_ch; 1231 n_ch++; 1232 } 1233 } 1234 1235 if (WARN_ON_ONCE(n_ch == 0)) 1236 return -EINVAL; 1237 1238 local->int_scan_req->n_channels = n_ch; 1239 } else { 1240 for (i = 0; i < n_channels; i++) { 1241 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR | 1242 IEEE80211_CHAN_DISABLED) || 1243 !cfg80211_wdev_channel_allowed(&sdata->wdev, 1244 channels[i])) 1245 continue; 1246 1247 local->int_scan_req->channels[n_ch] = channels[i]; 1248 n_ch++; 1249 } 1250 1251 if (n_ch == 0) 1252 return -EINVAL; 1253 1254 local->int_scan_req->n_channels = n_ch; 1255 } 1256 1257 local->int_scan_req->ssids = &local->scan_ssid; 1258 local->int_scan_req->n_ssids = 1; 1259 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); 1260 local->int_scan_req->ssids[0].ssid_len = ssid_len; 1261 1262 return __ieee80211_start_scan(sdata, sdata->local->int_scan_req); 1263 } 1264 1265 void ieee80211_scan_cancel(struct ieee80211_local *local) 1266 { 1267 /* ensure a new scan cannot be queued */ 1268 lockdep_assert_wiphy(local->hw.wiphy); 1269 1270 /* 1271 * We are canceling software scan, or deferred scan that was not 1272 * yet really started (see __ieee80211_start_scan ). 1273 * 1274 * Regarding hardware scan: 1275 * - we can not call __ieee80211_scan_completed() as when 1276 * SCAN_HW_SCANNING bit is set this function change 1277 * local->hw_scan_req to operate on 5G band, what race with 1278 * driver which can use local->hw_scan_req 1279 * 1280 * - we can not cancel scan_work since driver can schedule it 1281 * by ieee80211_scan_completed(..., true) to finish scan 1282 * 1283 * Hence we only call the cancel_hw_scan() callback, but the low-level 1284 * driver is still responsible for calling ieee80211_scan_completed() 1285 * after the scan was completed/aborted. 1286 */ 1287 1288 if (!local->scan_req) 1289 return; 1290 1291 /* 1292 * We have a scan running and the driver already reported completion, 1293 * but the worker hasn't run yet or is stuck on the mutex - mark it as 1294 * cancelled. 1295 */ 1296 if (test_bit(SCAN_HW_SCANNING, &local->scanning) && 1297 test_bit(SCAN_COMPLETED, &local->scanning)) { 1298 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1299 return; 1300 } 1301 1302 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) { 1303 /* 1304 * Make sure that __ieee80211_scan_completed doesn't trigger a 1305 * scan on another band. 1306 */ 1307 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1308 if (local->ops->cancel_hw_scan) 1309 drv_cancel_hw_scan(local, 1310 rcu_dereference_protected(local->scan_sdata, 1311 lockdep_is_held(&local->hw.wiphy->mtx))); 1312 return; 1313 } 1314 1315 wiphy_delayed_work_cancel(local->hw.wiphy, &local->scan_work); 1316 /* and clean up */ 1317 memset(&local->scan_info, 0, sizeof(local->scan_info)); 1318 __ieee80211_scan_completed(&local->hw, true); 1319 } 1320 1321 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1322 struct cfg80211_sched_scan_request *req) 1323 { 1324 struct ieee80211_local *local = sdata->local; 1325 struct ieee80211_scan_ies sched_scan_ies = {}; 1326 struct cfg80211_chan_def chandef; 1327 int ret, i, iebufsz, num_bands = 0; 1328 u32 rate_masks[NUM_NL80211_BANDS] = {}; 1329 u8 bands_used = 0; 1330 u8 *ie; 1331 u32 flags = 0; 1332 1333 lockdep_assert_wiphy(local->hw.wiphy); 1334 1335 iebufsz = local->scan_ies_len + req->ie_len; 1336 1337 if (!local->ops->sched_scan_start) 1338 return -EOPNOTSUPP; 1339 1340 for (i = 0; i < NUM_NL80211_BANDS; i++) { 1341 if (local->hw.wiphy->bands[i]) { 1342 bands_used |= BIT(i); 1343 rate_masks[i] = (u32) -1; 1344 num_bands++; 1345 } 1346 } 1347 1348 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 1349 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 1350 1351 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL); 1352 if (!ie) { 1353 ret = -ENOMEM; 1354 goto out; 1355 } 1356 1357 ieee80211_prepare_scan_chandef(&chandef); 1358 1359 ret = ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz, 1360 &sched_scan_ies, req->ie, 1361 req->ie_len, bands_used, rate_masks, 1362 &chandef, flags); 1363 if (ret < 0) 1364 goto error; 1365 1366 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies); 1367 if (ret == 0) { 1368 rcu_assign_pointer(local->sched_scan_sdata, sdata); 1369 rcu_assign_pointer(local->sched_scan_req, req); 1370 } 1371 1372 error: 1373 kfree(ie); 1374 out: 1375 if (ret) { 1376 /* Clean in case of failure after HW restart or upon resume. */ 1377 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1378 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1379 } 1380 1381 return ret; 1382 } 1383 1384 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1385 struct cfg80211_sched_scan_request *req) 1386 { 1387 struct ieee80211_local *local = sdata->local; 1388 1389 lockdep_assert_wiphy(local->hw.wiphy); 1390 1391 if (rcu_access_pointer(local->sched_scan_sdata)) 1392 return -EBUSY; 1393 1394 return __ieee80211_request_sched_scan_start(sdata, req); 1395 } 1396 1397 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local) 1398 { 1399 struct ieee80211_sub_if_data *sched_scan_sdata; 1400 int ret = -ENOENT; 1401 1402 lockdep_assert_wiphy(local->hw.wiphy); 1403 1404 if (!local->ops->sched_scan_stop) 1405 return -EOPNOTSUPP; 1406 1407 /* We don't want to restart sched scan anymore. */ 1408 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1409 1410 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata, 1411 lockdep_is_held(&local->hw.wiphy->mtx)); 1412 if (sched_scan_sdata) { 1413 ret = drv_sched_scan_stop(local, sched_scan_sdata); 1414 if (!ret) 1415 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1416 } 1417 1418 return ret; 1419 } 1420 1421 void ieee80211_sched_scan_results(struct ieee80211_hw *hw) 1422 { 1423 struct ieee80211_local *local = hw_to_local(hw); 1424 1425 trace_api_sched_scan_results(local); 1426 1427 cfg80211_sched_scan_results(hw->wiphy, 0); 1428 } 1429 EXPORT_SYMBOL(ieee80211_sched_scan_results); 1430 1431 void ieee80211_sched_scan_end(struct ieee80211_local *local) 1432 { 1433 lockdep_assert_wiphy(local->hw.wiphy); 1434 1435 if (!rcu_access_pointer(local->sched_scan_sdata)) 1436 return; 1437 1438 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1439 1440 /* If sched scan was aborted by the driver. */ 1441 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1442 1443 cfg80211_sched_scan_stopped_locked(local->hw.wiphy, 0); 1444 } 1445 1446 void ieee80211_sched_scan_stopped_work(struct wiphy *wiphy, 1447 struct wiphy_work *work) 1448 { 1449 struct ieee80211_local *local = 1450 container_of(work, struct ieee80211_local, 1451 sched_scan_stopped_work); 1452 1453 ieee80211_sched_scan_end(local); 1454 } 1455 1456 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw) 1457 { 1458 struct ieee80211_local *local = hw_to_local(hw); 1459 1460 trace_api_sched_scan_stopped(local); 1461 1462 /* 1463 * this shouldn't really happen, so for simplicity 1464 * simply ignore it, and let mac80211 reconfigure 1465 * the sched scan later on. 1466 */ 1467 if (local->in_reconfig) 1468 return; 1469 1470 wiphy_work_queue(hw->wiphy, &local->sched_scan_stopped_work); 1471 } 1472 EXPORT_SYMBOL(ieee80211_sched_scan_stopped); 1473