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) 2018-2026 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_elems_parse_params params = { 72 .mode = cbss->channel->band == NL80211_BAND_S1GHZ ? 73 IEEE80211_CONN_MODE_S1G : 74 IEEE80211_CONN_MODE_HIGHEST, 75 .start = ies->data, 76 .len = ies->len, 77 .link_id = -1, 78 }; 79 struct ieee80211_rx_status *rx_status; 80 struct ieee802_11_elems *elems; 81 int clen, srlen; 82 83 /* This happens while joining an IBSS */ 84 if (!update_data) 85 return; 86 87 params.type = update_data->beacon ? 88 IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_BEACON : 89 IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_PROBE_RESP; 90 91 elems = ieee802_11_parse_elems_full(¶ms); 92 if (!elems) 93 return; 94 95 rx_status = update_data->rx_status; 96 97 if (update_data->beacon) 98 bss->device_ts_beacon = rx_status->device_timestamp; 99 else 100 bss->device_ts_presp = rx_status->device_timestamp; 101 102 if (elems->parse_error) { 103 if (update_data->beacon) 104 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON; 105 else 106 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP; 107 } else { 108 if (update_data->beacon) 109 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON; 110 else 111 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP; 112 } 113 114 /* save the ERP value so that it is available at association time */ 115 if (elems->erp_info && (!elems->parse_error || 116 !(bss->valid_data & IEEE80211_BSS_VALID_ERP))) { 117 bss->erp_value = elems->erp_info[0]; 118 bss->has_erp_value = true; 119 if (!elems->parse_error) 120 bss->valid_data |= IEEE80211_BSS_VALID_ERP; 121 } 122 123 /* replace old supported rates if we get new values */ 124 if (!elems->parse_error || 125 !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) { 126 srlen = 0; 127 if (elems->supp_rates) { 128 clen = IEEE80211_MAX_SUPP_RATES; 129 if (clen > elems->supp_rates_len) 130 clen = elems->supp_rates_len; 131 memcpy(bss->supp_rates, elems->supp_rates, clen); 132 srlen += clen; 133 } 134 if (elems->ext_supp_rates) { 135 clen = IEEE80211_MAX_SUPP_RATES - srlen; 136 if (clen > elems->ext_supp_rates_len) 137 clen = elems->ext_supp_rates_len; 138 memcpy(bss->supp_rates + srlen, elems->ext_supp_rates, 139 clen); 140 srlen += clen; 141 } 142 if (srlen) { 143 bss->supp_rates_len = srlen; 144 if (!elems->parse_error) 145 bss->valid_data |= IEEE80211_BSS_VALID_RATES; 146 } 147 } 148 149 if (!elems->parse_error || 150 !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) { 151 bss->wmm_used = elems->wmm_param || elems->wmm_info; 152 bss->uapsd_supported = is_uapsd_supported(elems); 153 if (!elems->parse_error) 154 bss->valid_data |= IEEE80211_BSS_VALID_WMM; 155 } 156 157 if (update_data->beacon) { 158 struct ieee80211_supported_band *sband = 159 local->hw.wiphy->bands[rx_status->band]; 160 if (!(rx_status->encoding == RX_ENC_HT) && 161 !(rx_status->encoding == RX_ENC_VHT)) 162 bss->beacon_rate = 163 &sband->bitrates[rx_status->rate_idx]; 164 } 165 166 if (elems->vht_cap_elem) 167 bss->vht_cap_info = 168 le32_to_cpu(elems->vht_cap_elem->vht_cap_info); 169 else 170 bss->vht_cap_info = 0; 171 172 kfree(elems); 173 } 174 175 struct ieee80211_bss * 176 ieee80211_bss_info_update(struct ieee80211_local *local, 177 struct ieee80211_rx_status *rx_status, 178 struct ieee80211_mgmt *mgmt, size_t len, 179 struct ieee80211_channel *channel) 180 { 181 bool beacon = ieee80211_is_beacon(mgmt->frame_control) || 182 ieee80211_is_s1g_beacon(mgmt->frame_control); 183 struct cfg80211_bss *cbss; 184 struct inform_bss_update_data update_data = { 185 .rx_status = rx_status, 186 .beacon = beacon, 187 }; 188 struct cfg80211_inform_bss bss_meta = { 189 .boottime_ns = rx_status->boottime_ns, 190 .drv_data = (void *)&update_data, 191 }; 192 bool signal_valid; 193 struct ieee80211_sub_if_data *scan_sdata; 194 195 if (rx_status->flag & RX_FLAG_NO_SIGNAL_VAL) 196 bss_meta.signal = 0; /* invalid signal indication */ 197 else if (ieee80211_hw_check(&local->hw, SIGNAL_DBM)) 198 bss_meta.signal = rx_status->signal * 100; 199 else if (ieee80211_hw_check(&local->hw, SIGNAL_UNSPEC)) 200 bss_meta.signal = (rx_status->signal * 100) / local->hw.max_signal; 201 202 bss_meta.chan = channel; 203 204 rcu_read_lock(); 205 scan_sdata = rcu_dereference(local->scan_sdata); 206 if (scan_sdata && scan_sdata->vif.type == NL80211_IFTYPE_STATION && 207 scan_sdata->vif.cfg.assoc && 208 ieee80211_have_rx_timestamp(rx_status)) { 209 struct ieee80211_bss_conf *link_conf = NULL; 210 211 /* for an MLO connection, set the TSF data only in case we have 212 * an indication on which of the links the frame was received 213 */ 214 if (ieee80211_vif_is_mld(&scan_sdata->vif)) { 215 s8 link_id = rx_status->link_id; 216 217 link_conf = 218 rcu_dereference(scan_sdata->vif.link_conf[link_id]); 219 } else { 220 link_conf = &scan_sdata->vif.bss_conf; 221 } 222 223 if (link_conf) { 224 bss_meta.parent_tsf = 225 ieee80211_calculate_rx_timestamp(&local->hw, 226 rx_status, 227 len + FCS_LEN, 228 24); 229 230 ether_addr_copy(bss_meta.parent_bssid, 231 link_conf->bssid); 232 } 233 } 234 rcu_read_unlock(); 235 236 cbss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, 237 mgmt, len, GFP_ATOMIC); 238 if (!cbss) 239 return NULL; 240 241 /* In case the signal is invalid update the status */ 242 signal_valid = channel == cbss->channel; 243 if (!signal_valid) 244 rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL; 245 246 return (void *)cbss->priv; 247 } 248 249 static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata, 250 struct ieee80211_channel *channel, 251 u32 scan_flags, const u8 *da) 252 { 253 struct ieee80211_link_data *link_sdata; 254 u8 link_id; 255 256 if (!sdata) 257 return false; 258 259 /* accept broadcast on 6 GHz and for OCE */ 260 if (is_broadcast_ether_addr(da) && 261 (channel->band == NL80211_BAND_6GHZ || 262 scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP)) 263 return true; 264 265 if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 266 return true; 267 268 if (ether_addr_equal(da, sdata->vif.addr)) 269 return true; 270 271 for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) { 272 link_sdata = rcu_dereference(sdata->link[link_id]); 273 if (!link_sdata) 274 continue; 275 276 if (ether_addr_equal(da, link_sdata->conf->addr)) 277 return true; 278 } 279 280 return false; 281 } 282 283 void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb) 284 { 285 struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); 286 struct ieee80211_mgmt *mgmt = (void *)skb->data; 287 struct ieee80211_bss *bss; 288 struct ieee80211_channel *channel; 289 struct ieee80211_ext *ext; 290 size_t min_hdr_len = offsetof(struct ieee80211_mgmt, 291 u.probe_resp.variable); 292 293 if (!ieee80211_is_probe_resp(mgmt->frame_control) && 294 !ieee80211_is_beacon(mgmt->frame_control) && 295 !ieee80211_is_s1g_beacon(mgmt->frame_control)) 296 return; 297 298 if (ieee80211_is_s1g_beacon(mgmt->frame_control)) { 299 ext = (struct ieee80211_ext *)mgmt; 300 min_hdr_len = 301 offsetof(struct ieee80211_ext, u.s1g_beacon.variable) + 302 ieee80211_s1g_optional_len(ext->frame_control); 303 } 304 305 if (skb->len < min_hdr_len) 306 return; 307 308 if (test_and_clear_bit(SCAN_BEACON_WAIT, &local->scanning)) { 309 /* 310 * we were passive scanning because of radar/no-IR, but 311 * the beacon/proberesp rx gives us an opportunity to upgrade 312 * to active scan 313 */ 314 set_bit(SCAN_BEACON_DONE, &local->scanning); 315 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 0); 316 } 317 318 channel = ieee80211_get_channel_khz(local->hw.wiphy, 319 ieee80211_rx_status_to_khz(rx_status)); 320 321 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 322 return; 323 324 if (ieee80211_is_probe_resp(mgmt->frame_control)) { 325 struct ieee80211_sub_if_data *sdata1, *sdata2; 326 struct cfg80211_scan_request *scan_req; 327 struct cfg80211_sched_scan_request *sched_scan_req; 328 u32 scan_req_flags = 0, sched_scan_req_flags = 0; 329 330 sdata1 = rcu_dereference(local->scan_sdata); 331 sdata2 = rcu_dereference(local->sched_scan_sdata); 332 333 if (likely(!sdata1 && !sdata2)) 334 return; 335 336 scan_req = rcu_dereference(local->scan_req); 337 sched_scan_req = rcu_dereference(local->sched_scan_req); 338 339 if (scan_req) 340 scan_req_flags = scan_req->flags; 341 342 if (sched_scan_req) 343 sched_scan_req_flags = sched_scan_req->flags; 344 345 /* ignore ProbeResp to foreign address or non-bcast (OCE) 346 * unless scanning with randomised address 347 */ 348 if (!ieee80211_scan_accept_presp(sdata1, channel, 349 scan_req_flags, 350 mgmt->da) && 351 !ieee80211_scan_accept_presp(sdata2, channel, 352 sched_scan_req_flags, 353 mgmt->da)) 354 return; 355 } else { 356 /* 357 * Non-S1G beacons are expected only with broadcast address. 358 * S1G beacons only carry the SA so no DA check is required 359 * nor possible. 360 */ 361 if (!ieee80211_is_s1g_beacon(mgmt->frame_control) && 362 !is_broadcast_ether_addr(mgmt->da)) 363 return; 364 } 365 366 /* Do not update the BSS table in case of only monitor interfaces */ 367 if (local->open_count == local->monitors) 368 return; 369 370 bss = ieee80211_bss_info_update(local, rx_status, 371 mgmt, skb->len, 372 channel); 373 if (bss) 374 ieee80211_rx_bss_put(local, bss); 375 } 376 377 static void ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef) 378 { 379 memset(chandef, 0, sizeof(*chandef)); 380 381 chandef->width = NL80211_CHAN_WIDTH_20_NOHT; 382 } 383 384 /* return false if no more work */ 385 static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data *sdata) 386 { 387 struct ieee80211_local *local = sdata->local; 388 struct cfg80211_scan_request *req; 389 struct cfg80211_chan_def chandef; 390 u8 bands_used = 0; 391 int i, ielen; 392 u32 *n_chans; 393 u32 flags = 0; 394 395 req = rcu_dereference_protected(local->scan_req, 396 lockdep_is_held(&local->hw.wiphy->mtx)); 397 398 if (test_bit(SCAN_HW_CANCELLED, &local->scanning)) 399 return false; 400 401 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 402 local->hw_scan_req->req.n_channels = req->n_channels; 403 404 for (i = 0; i < req->n_channels; i++) { 405 local->hw_scan_req->req.channels[i] = req->channels[i]; 406 bands_used |= BIT(req->channels[i]->band); 407 } 408 } else { 409 do { 410 if (local->hw_scan_band == NUM_NL80211_BANDS) 411 return false; 412 413 n_chans = &local->hw_scan_req->req.n_channels; 414 *n_chans = 0; 415 416 for (i = 0; i < req->n_channels; i++) { 417 if (req->channels[i]->band != 418 local->hw_scan_band) 419 continue; 420 local->hw_scan_req->req.channels[(*n_chans)++] = 421 req->channels[i]; 422 423 bands_used |= BIT(req->channels[i]->band); 424 } 425 426 local->hw_scan_band++; 427 } while (!*n_chans); 428 } 429 430 ieee80211_prepare_scan_chandef(&chandef); 431 432 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 433 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 434 435 ielen = ieee80211_build_preq_ies(sdata, 436 (u8 *)local->hw_scan_req->req.ie, 437 local->hw_scan_ies_bufsize, 438 &local->hw_scan_req->ies, 439 req->ie, req->ie_len, 440 bands_used, req->rates, &chandef, 441 flags); 442 if (ielen < 0) 443 return false; 444 local->hw_scan_req->req.ie_len = ielen; 445 local->hw_scan_req->req.no_cck = req->no_cck; 446 ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr); 447 ether_addr_copy(local->hw_scan_req->req.mac_addr_mask, 448 req->mac_addr_mask); 449 ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid); 450 451 return true; 452 } 453 454 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) 455 { 456 struct ieee80211_local *local = hw_to_local(hw); 457 bool hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); 458 bool was_scanning = local->scanning; 459 struct cfg80211_scan_request *scan_req; 460 struct ieee80211_sub_if_data *scan_sdata; 461 struct ieee80211_sub_if_data *sdata; 462 463 lockdep_assert_wiphy(local->hw.wiphy); 464 465 /* 466 * It's ok to abort a not-yet-running scan (that 467 * we have one at all will be verified by checking 468 * local->scan_req next), but not to complete it 469 * successfully. 470 */ 471 if (WARN_ON(!local->scanning && !aborted)) 472 aborted = true; 473 474 if (WARN_ON(!local->scan_req)) 475 return; 476 477 scan_sdata = rcu_dereference_protected(local->scan_sdata, 478 lockdep_is_held(&local->hw.wiphy->mtx)); 479 480 if (hw_scan && !aborted && 481 !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) && 482 ieee80211_prep_hw_scan(scan_sdata)) { 483 int rc; 484 485 rc = drv_hw_scan(local, 486 rcu_dereference_protected(local->scan_sdata, 487 lockdep_is_held(&local->hw.wiphy->mtx)), 488 local->hw_scan_req); 489 490 if (rc == 0) 491 return; 492 493 /* HW scan failed and is going to be reported as aborted, 494 * so clear old scan info. 495 */ 496 memset(&local->scan_info, 0, sizeof(local->scan_info)); 497 aborted = true; 498 } 499 500 kfree(local->hw_scan_req); 501 local->hw_scan_req = NULL; 502 503 scan_req = rcu_dereference_protected(local->scan_req, 504 lockdep_is_held(&local->hw.wiphy->mtx)); 505 506 RCU_INIT_POINTER(local->scan_req, NULL); 507 RCU_INIT_POINTER(local->scan_sdata, NULL); 508 509 local->scanning = 0; 510 local->scan_chandef.chan = NULL; 511 512 synchronize_rcu(); 513 514 if (scan_req != local->int_scan_req) { 515 local->scan_info.aborted = aborted; 516 cfg80211_scan_done(scan_req, &local->scan_info); 517 } 518 519 /* Set power back to normal operating levels. */ 520 ieee80211_hw_conf_chan(local); 521 522 if (!hw_scan && was_scanning) { 523 ieee80211_configure_filter(local); 524 drv_sw_scan_complete(local, scan_sdata); 525 ieee80211_offchannel_return(local); 526 } 527 528 ieee80211_recalc_idle(local); 529 530 ieee80211_mlme_notify_scan_completed(local); 531 ieee80211_ibss_notify_scan_completed(local); 532 533 /* Requeue all the work that might have been ignored while 534 * the scan was in progress; if there was none this will 535 * just be a no-op for the particular interface. 536 */ 537 list_for_each_entry(sdata, &local->interfaces, list) { 538 if (ieee80211_sdata_running(sdata)) 539 wiphy_work_queue(sdata->local->hw.wiphy, &sdata->work); 540 } 541 542 if (was_scanning) 543 ieee80211_start_next_roc(local); 544 } 545 546 void ieee80211_scan_completed(struct ieee80211_hw *hw, 547 struct cfg80211_scan_info *info) 548 { 549 struct ieee80211_local *local = hw_to_local(hw); 550 551 trace_api_scan_completed(local, info->aborted); 552 553 set_bit(SCAN_COMPLETED, &local->scanning); 554 if (info->aborted) 555 set_bit(SCAN_ABORTED, &local->scanning); 556 557 memcpy(&local->scan_info, info, sizeof(*info)); 558 559 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 0); 560 } 561 EXPORT_SYMBOL(ieee80211_scan_completed); 562 563 static int ieee80211_start_sw_scan(struct ieee80211_local *local, 564 struct ieee80211_sub_if_data *sdata) 565 { 566 /* Software scan is not supported in multi-channel cases */ 567 if (!local->emulate_chanctx) 568 return -EOPNOTSUPP; 569 570 /* 571 * Hardware/driver doesn't support hw_scan, so use software 572 * scanning instead. First send a nullfunc frame with power save 573 * bit on so that AP will buffer the frames for us while we are not 574 * listening, then send probe requests to each channel and wait for 575 * the responses. After all channels are scanned, tune back to the 576 * original channel and send a nullfunc frame with power save bit 577 * off to trigger the AP to send us all the buffered frames. 578 * 579 * Note that while local->sw_scanning is true everything else but 580 * nullfunc frames and probe requests will be dropped in 581 * ieee80211_tx_h_check_assoc(). 582 */ 583 drv_sw_scan_start(local, sdata, local->scan_addr); 584 585 local->leave_oper_channel_time = jiffies; 586 local->next_scan_state = SCAN_DECISION; 587 local->scan_channel_idx = 0; 588 589 ieee80211_offchannel_stop_vifs(local); 590 591 /* ensure nullfunc is transmitted before leaving operating channel */ 592 ieee80211_flush_queues(local, NULL, false); 593 594 ieee80211_configure_filter(local); 595 596 /* We need to set power level at maximum rate for scanning. */ 597 ieee80211_hw_conf_chan(local); 598 599 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 0); 600 601 return 0; 602 } 603 604 static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata, 605 struct cfg80211_scan_request *req) 606 { 607 struct ieee80211_local *local = sdata->local; 608 struct ieee80211_sub_if_data *sdata_iter; 609 unsigned int link_id; 610 611 lockdep_assert_wiphy(local->hw.wiphy); 612 613 if (!ieee80211_is_radar_required(local, req)) 614 return true; 615 616 if (!regulatory_pre_cac_allowed(local->hw.wiphy)) 617 return false; 618 619 list_for_each_entry(sdata_iter, &local->interfaces, list) { 620 for_each_valid_link(&sdata_iter->wdev, link_id) 621 if (sdata_iter->wdev.links[link_id].cac_started) 622 return false; 623 } 624 625 return true; 626 } 627 628 static bool ieee80211_can_scan(struct ieee80211_local *local, 629 struct ieee80211_sub_if_data *sdata, 630 struct cfg80211_scan_request *req) 631 { 632 if (!__ieee80211_can_leave_ch(sdata, req)) 633 return false; 634 635 if (!list_empty(&local->roc_list)) 636 return false; 637 638 if (sdata->vif.type == NL80211_IFTYPE_STATION && 639 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL) 640 return false; 641 642 return true; 643 } 644 645 void ieee80211_run_deferred_scan(struct ieee80211_local *local) 646 { 647 struct cfg80211_scan_request *req; 648 649 lockdep_assert_wiphy(local->hw.wiphy); 650 651 if (!local->scan_req || local->scanning) 652 return; 653 654 req = wiphy_dereference(local->hw.wiphy, local->scan_req); 655 if (!ieee80211_can_scan(local, 656 rcu_dereference_protected( 657 local->scan_sdata, 658 lockdep_is_held(&local->hw.wiphy->mtx)), 659 req)) 660 return; 661 662 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 663 round_jiffies_relative(0)); 664 } 665 666 static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata, 667 const u8 *src, const u8 *dst, 668 const u8 *ssid, size_t ssid_len, 669 const u8 *ie, size_t ie_len, 670 u32 ratemask, u32 flags, u32 tx_flags, 671 struct ieee80211_channel *channel) 672 { 673 struct sk_buff *skb; 674 675 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel, 676 ssid, ssid_len, 677 ie, ie_len, flags); 678 679 if (skb) { 680 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) { 681 struct ieee80211_hdr *hdr = (void *)skb->data; 682 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 683 u16 sn = get_random_u16(); 684 685 info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO; 686 hdr->seq_ctrl = 687 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn)); 688 } 689 IEEE80211_SKB_CB(skb)->flags |= tx_flags; 690 IEEE80211_SKB_CB(skb)->control.flags |= IEEE80211_TX_CTRL_DONT_USE_RATE_MASK; 691 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band); 692 } 693 } 694 695 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, 696 unsigned long *next_delay) 697 { 698 int i; 699 struct ieee80211_sub_if_data *sdata; 700 struct cfg80211_scan_request *scan_req; 701 enum nl80211_band band = local->hw.conf.chandef.chan->band; 702 u32 flags = 0, tx_flags; 703 704 scan_req = rcu_dereference_protected(local->scan_req, 705 lockdep_is_held(&local->hw.wiphy->mtx)); 706 707 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK; 708 if (scan_req->no_cck) 709 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE; 710 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 711 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 712 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN) 713 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN; 714 715 sdata = rcu_dereference_protected(local->scan_sdata, 716 lockdep_is_held(&local->hw.wiphy->mtx)); 717 718 for (i = 0; i < scan_req->n_ssids; i++) 719 ieee80211_send_scan_probe_req( 720 sdata, local->scan_addr, scan_req->bssid, 721 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len, 722 scan_req->ie, scan_req->ie_len, 723 scan_req->rates[band], flags, 724 tx_flags, local->hw.conf.chandef.chan); 725 726 /* 727 * After sending probe requests, wait for probe responses 728 * on the channel. 729 */ 730 *next_delay = msecs_to_jiffies(scan_req->duration) > 731 IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME ? 732 msecs_to_jiffies(scan_req->duration) - IEEE80211_PROBE_DELAY : 733 IEEE80211_CHANNEL_TIME; 734 local->next_scan_state = SCAN_DECISION; 735 } 736 737 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, 738 struct cfg80211_scan_request *req) 739 { 740 struct ieee80211_local *local = sdata->local; 741 bool hw_scan = local->ops->hw_scan; 742 int rc; 743 744 lockdep_assert_wiphy(local->hw.wiphy); 745 746 if (local->scan_req) 747 return -EBUSY; 748 749 /* For an MLO connection, if a link ID was specified, validate that it 750 * is indeed active. 751 */ 752 if (ieee80211_vif_is_mld(&sdata->vif) && req->tsf_report_link_id >= 0 && 753 !(sdata->vif.active_links & BIT(req->tsf_report_link_id))) 754 return -EINVAL; 755 756 if (!__ieee80211_can_leave_ch(sdata, req)) 757 return -EBUSY; 758 759 if (!ieee80211_can_scan(local, sdata, req)) { 760 /* wait for the work to finish/time out */ 761 rcu_assign_pointer(local->scan_req, req); 762 rcu_assign_pointer(local->scan_sdata, sdata); 763 return 0; 764 } 765 766 again: 767 if (hw_scan) { 768 u8 *ies; 769 770 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len; 771 772 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 773 int i, n_bands = 0; 774 u8 bands_counted = 0; 775 776 for (i = 0; i < req->n_channels; i++) { 777 if (bands_counted & BIT(req->channels[i]->band)) 778 continue; 779 bands_counted |= BIT(req->channels[i]->band); 780 n_bands++; 781 } 782 783 local->hw_scan_ies_bufsize *= n_bands; 784 } 785 786 local->hw_scan_req = kmalloc(struct_size(local->hw_scan_req, 787 req.channels, 788 req->n_channels) + 789 local->hw_scan_ies_bufsize, 790 GFP_KERNEL); 791 if (!local->hw_scan_req) 792 return -ENOMEM; 793 794 local->hw_scan_req->req.ssids = req->ssids; 795 local->hw_scan_req->req.n_ssids = req->n_ssids; 796 /* None of the channels are actually set 797 * up but let UBSAN know the boundaries. 798 */ 799 local->hw_scan_req->req.n_channels = req->n_channels; 800 801 ies = (u8 *)local->hw_scan_req + 802 sizeof(*local->hw_scan_req) + 803 req->n_channels * sizeof(req->channels[0]); 804 local->hw_scan_req->req.ie = ies; 805 local->hw_scan_req->req.flags = req->flags; 806 eth_broadcast_addr(local->hw_scan_req->req.bssid); 807 local->hw_scan_req->req.duration = req->duration; 808 local->hw_scan_req->req.duration_mandatory = 809 req->duration_mandatory; 810 local->hw_scan_req->req.tsf_report_link_id = 811 req->tsf_report_link_id; 812 813 local->hw_scan_band = 0; 814 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params; 815 local->hw_scan_req->req.scan_6ghz_params = 816 req->scan_6ghz_params; 817 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz; 818 local->hw_scan_req->req.first_part = req->first_part; 819 820 /* 821 * After allocating local->hw_scan_req, we must 822 * go through until ieee80211_prep_hw_scan(), so 823 * anything that might be changed here and leave 824 * this function early must not go after this 825 * allocation. 826 */ 827 } 828 829 rcu_assign_pointer(local->scan_req, req); 830 rcu_assign_pointer(local->scan_sdata, sdata); 831 832 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 833 get_random_mask_addr(local->scan_addr, 834 req->mac_addr, 835 req->mac_addr_mask); 836 else 837 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN); 838 839 if (hw_scan) { 840 __set_bit(SCAN_HW_SCANNING, &local->scanning); 841 } else if ((req->n_channels == 1) && 842 (req->channels[0] == local->hw.conf.chandef.chan)) { 843 /* 844 * If we are scanning only on the operating channel 845 * then we do not need to stop normal activities 846 */ 847 unsigned long next_delay; 848 849 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning); 850 851 ieee80211_recalc_idle(local); 852 853 /* Notify driver scan is starting, keep order of operations 854 * same as normal software scan, in case that matters. */ 855 drv_sw_scan_start(local, sdata, local->scan_addr); 856 857 ieee80211_configure_filter(local); /* accept probe-responses */ 858 859 /* We need to ensure power level is at max for scanning. */ 860 ieee80211_hw_conf_chan(local); 861 862 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR | 863 IEEE80211_CHAN_RADAR)) || 864 !req->n_ssids) { 865 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 866 if (req->n_ssids) 867 set_bit(SCAN_BEACON_WAIT, &local->scanning); 868 } else { 869 ieee80211_scan_state_send_probe(local, &next_delay); 870 next_delay = IEEE80211_CHANNEL_TIME; 871 } 872 873 /* Now, just wait a bit and we are all done! */ 874 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 875 next_delay); 876 return 0; 877 } else { 878 /* Do normal software scan */ 879 __set_bit(SCAN_SW_SCANNING, &local->scanning); 880 } 881 882 ieee80211_recalc_idle(local); 883 884 if (hw_scan) { 885 WARN_ON(!ieee80211_prep_hw_scan(sdata)); 886 rc = drv_hw_scan(local, sdata, local->hw_scan_req); 887 } else { 888 rc = ieee80211_start_sw_scan(local, sdata); 889 } 890 891 if (rc) { 892 kfree(local->hw_scan_req); 893 local->hw_scan_req = NULL; 894 local->scanning = 0; 895 896 ieee80211_recalc_idle(local); 897 898 local->scan_req = NULL; 899 RCU_INIT_POINTER(local->scan_sdata, NULL); 900 } 901 902 if (hw_scan && rc == 1) { 903 /* 904 * we can't fall back to software for P2P-GO 905 * as it must update NoA etc. 906 */ 907 if (ieee80211_vif_type_p2p(&sdata->vif) == 908 NL80211_IFTYPE_P2P_GO) 909 return -EOPNOTSUPP; 910 hw_scan = false; 911 goto again; 912 } 913 914 return rc; 915 } 916 917 static unsigned long 918 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) 919 { 920 /* 921 * TODO: channel switching also consumes quite some time, 922 * add that delay as well to get a better estimation 923 */ 924 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) 925 return IEEE80211_PASSIVE_CHANNEL_TIME; 926 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; 927 } 928 929 static void ieee80211_scan_state_decision(struct ieee80211_local *local, 930 unsigned long *next_delay) 931 { 932 bool associated = false; 933 bool tx_empty = true; 934 bool bad_latency; 935 struct ieee80211_sub_if_data *sdata; 936 struct ieee80211_channel *next_chan; 937 enum mac80211_scan_state next_scan_state; 938 struct cfg80211_scan_request *scan_req; 939 940 lockdep_assert_wiphy(local->hw.wiphy); 941 942 /* 943 * check if at least one STA interface is associated, 944 * check if at least one STA interface has pending tx frames 945 * and grab the lowest used beacon interval 946 */ 947 list_for_each_entry(sdata, &local->interfaces, list) { 948 if (!ieee80211_sdata_running(sdata)) 949 continue; 950 951 if (sdata->vif.type == NL80211_IFTYPE_STATION) { 952 if (sdata->u.mgd.associated) { 953 associated = true; 954 955 if (!qdisc_all_tx_empty(sdata->dev)) { 956 tx_empty = false; 957 break; 958 } 959 } 960 } 961 } 962 963 scan_req = rcu_dereference_protected(local->scan_req, 964 lockdep_is_held(&local->hw.wiphy->mtx)); 965 966 next_chan = scan_req->channels[local->scan_channel_idx]; 967 968 /* 969 * we're currently scanning a different channel, let's 970 * see if we can scan another channel without interfering 971 * with the current traffic situation. 972 * 973 * Keep good latency, do not stay off-channel more than 125 ms. 974 */ 975 976 bad_latency = time_after(jiffies + 977 ieee80211_scan_get_channel_time(next_chan), 978 local->leave_oper_channel_time + HZ / 8); 979 980 if (associated && !tx_empty) { 981 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY) 982 next_scan_state = SCAN_ABORT; 983 else 984 next_scan_state = SCAN_SUSPEND; 985 } else if (associated && bad_latency) { 986 next_scan_state = SCAN_SUSPEND; 987 } else { 988 next_scan_state = SCAN_SET_CHANNEL; 989 } 990 991 local->next_scan_state = next_scan_state; 992 993 *next_delay = 0; 994 } 995 996 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, 997 unsigned long *next_delay) 998 { 999 int skip; 1000 struct ieee80211_channel *chan; 1001 struct cfg80211_scan_request *scan_req; 1002 1003 scan_req = rcu_dereference_protected(local->scan_req, 1004 lockdep_is_held(&local->hw.wiphy->mtx)); 1005 1006 skip = 0; 1007 chan = scan_req->channels[local->scan_channel_idx]; 1008 1009 local->scan_chandef.chan = chan; 1010 local->scan_chandef.center_freq1 = chan->center_freq; 1011 local->scan_chandef.freq1_offset = chan->freq_offset; 1012 local->scan_chandef.center_freq2 = 0; 1013 1014 /* For S1G, only scan the 1MHz primaries. */ 1015 if (chan->band == NL80211_BAND_S1GHZ) { 1016 local->scan_chandef.width = NL80211_CHAN_WIDTH_1; 1017 local->scan_chandef.s1g_primary_2mhz = false; 1018 goto set_channel; 1019 } 1020 1021 /* 1022 * If scanning on oper channel, use whatever channel-type 1023 * is currently in use. 1024 */ 1025 if (chan == local->hw.conf.chandef.chan) 1026 local->scan_chandef = local->hw.conf.chandef; 1027 else 1028 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT; 1029 1030 set_channel: 1031 if (ieee80211_hw_conf_chan(local)) 1032 skip = 1; 1033 1034 /* advance state machine to next channel/band */ 1035 local->scan_channel_idx++; 1036 1037 if (skip) { 1038 /* if we skip this channel return to the decision state */ 1039 local->next_scan_state = SCAN_DECISION; 1040 return; 1041 } 1042 1043 /* 1044 * Probe delay is used to update the NAV, cf. 11.1.3.2.2 1045 * (which unfortunately doesn't say _why_ step a) is done, 1046 * but it waits for the probe delay or until a frame is 1047 * received - and the received frame would update the NAV). 1048 * For now, we do not support waiting until a frame is 1049 * received. 1050 * 1051 * In any case, it is not necessary for a passive scan. 1052 */ 1053 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) || 1054 !scan_req->n_ssids) { 1055 *next_delay = max(msecs_to_jiffies(scan_req->duration), 1056 IEEE80211_PASSIVE_CHANNEL_TIME); 1057 local->next_scan_state = SCAN_DECISION; 1058 if (scan_req->n_ssids) 1059 set_bit(SCAN_BEACON_WAIT, &local->scanning); 1060 return; 1061 } 1062 1063 /* active scan, send probes */ 1064 *next_delay = IEEE80211_PROBE_DELAY; 1065 local->next_scan_state = SCAN_SEND_PROBE; 1066 } 1067 1068 static void ieee80211_scan_state_suspend(struct ieee80211_local *local, 1069 unsigned long *next_delay) 1070 { 1071 /* switch back to the operating channel */ 1072 local->scan_chandef.chan = NULL; 1073 ieee80211_hw_conf_chan(local); 1074 1075 /* disable PS */ 1076 ieee80211_offchannel_return(local); 1077 1078 *next_delay = HZ / 5; 1079 /* afterwards, resume scan & go to next channel */ 1080 local->next_scan_state = SCAN_RESUME; 1081 } 1082 1083 static void ieee80211_scan_state_resume(struct ieee80211_local *local, 1084 unsigned long *next_delay) 1085 { 1086 ieee80211_offchannel_stop_vifs(local); 1087 1088 if (local->ops->flush) { 1089 ieee80211_flush_queues(local, NULL, false); 1090 *next_delay = 0; 1091 } else 1092 *next_delay = HZ / 10; 1093 1094 /* remember when we left the operating channel */ 1095 local->leave_oper_channel_time = jiffies; 1096 1097 /* advance to the next channel to be scanned */ 1098 local->next_scan_state = SCAN_SET_CHANNEL; 1099 } 1100 1101 void ieee80211_scan_work(struct wiphy *wiphy, struct wiphy_work *work) 1102 { 1103 struct ieee80211_local *local = 1104 container_of(work, struct ieee80211_local, scan_work.work); 1105 struct ieee80211_sub_if_data *sdata; 1106 struct cfg80211_scan_request *scan_req; 1107 unsigned long next_delay = 0; 1108 bool aborted; 1109 1110 lockdep_assert_wiphy(local->hw.wiphy); 1111 1112 if (!ieee80211_can_run_worker(local)) { 1113 aborted = true; 1114 goto out_complete; 1115 } 1116 1117 sdata = rcu_dereference_protected(local->scan_sdata, 1118 lockdep_is_held(&local->hw.wiphy->mtx)); 1119 scan_req = rcu_dereference_protected(local->scan_req, 1120 lockdep_is_held(&local->hw.wiphy->mtx)); 1121 1122 /* When scanning on-channel, the first-callback means completed. */ 1123 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) { 1124 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1125 goto out_complete; 1126 } 1127 1128 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) { 1129 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1130 goto out_complete; 1131 } 1132 1133 if (!sdata || !scan_req) 1134 return; 1135 1136 if (!local->scanning) { 1137 int rc; 1138 1139 RCU_INIT_POINTER(local->scan_req, NULL); 1140 RCU_INIT_POINTER(local->scan_sdata, NULL); 1141 1142 rc = __ieee80211_start_scan(sdata, scan_req); 1143 if (!rc) 1144 return; 1145 /* need to complete scan in cfg80211 */ 1146 rcu_assign_pointer(local->scan_req, scan_req); 1147 aborted = true; 1148 goto out_complete; 1149 } 1150 1151 clear_bit(SCAN_BEACON_WAIT, &local->scanning); 1152 1153 /* 1154 * as long as no delay is required advance immediately 1155 * without scheduling a new work 1156 */ 1157 do { 1158 if (!ieee80211_sdata_running(sdata)) { 1159 aborted = true; 1160 goto out_complete; 1161 } 1162 1163 if (test_and_clear_bit(SCAN_BEACON_DONE, &local->scanning) && 1164 local->next_scan_state == SCAN_DECISION) 1165 local->next_scan_state = SCAN_SEND_PROBE; 1166 1167 switch (local->next_scan_state) { 1168 case SCAN_DECISION: 1169 /* if no more bands/channels left, complete scan */ 1170 if (local->scan_channel_idx >= scan_req->n_channels) { 1171 aborted = false; 1172 goto out_complete; 1173 } 1174 ieee80211_scan_state_decision(local, &next_delay); 1175 break; 1176 case SCAN_SET_CHANNEL: 1177 ieee80211_scan_state_set_channel(local, &next_delay); 1178 break; 1179 case SCAN_SEND_PROBE: 1180 ieee80211_scan_state_send_probe(local, &next_delay); 1181 break; 1182 case SCAN_SUSPEND: 1183 ieee80211_scan_state_suspend(local, &next_delay); 1184 break; 1185 case SCAN_RESUME: 1186 ieee80211_scan_state_resume(local, &next_delay); 1187 break; 1188 case SCAN_ABORT: 1189 aborted = true; 1190 goto out_complete; 1191 } 1192 } while (next_delay == 0); 1193 1194 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 1195 next_delay); 1196 return; 1197 1198 out_complete: 1199 __ieee80211_scan_completed(&local->hw, aborted); 1200 } 1201 1202 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, 1203 struct cfg80211_scan_request *req) 1204 { 1205 lockdep_assert_wiphy(sdata->local->hw.wiphy); 1206 1207 return __ieee80211_start_scan(sdata, req); 1208 } 1209 1210 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata, 1211 const u8 *ssid, u8 ssid_len, 1212 struct ieee80211_channel **channels, 1213 unsigned int n_channels) 1214 { 1215 struct ieee80211_local *local = sdata->local; 1216 int i, n_ch = 0; 1217 enum nl80211_band band; 1218 1219 lockdep_assert_wiphy(local->hw.wiphy); 1220 1221 /* busy scanning */ 1222 if (local->scan_req) 1223 return -EBUSY; 1224 1225 /* fill internal scan request */ 1226 if (!channels) { 1227 int max_n; 1228 1229 for (band = 0; band < NUM_NL80211_BANDS; band++) { 1230 if (!local->hw.wiphy->bands[band] || 1231 band == NL80211_BAND_6GHZ || 1232 band == NL80211_BAND_S1GHZ) 1233 continue; 1234 1235 max_n = local->hw.wiphy->bands[band]->n_channels; 1236 for (i = 0; i < max_n; i++) { 1237 struct ieee80211_channel *tmp_ch = 1238 &local->hw.wiphy->bands[band]->channels[i]; 1239 1240 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR | 1241 IEEE80211_CHAN_DISABLED) || 1242 !cfg80211_wdev_channel_allowed(&sdata->wdev, 1243 tmp_ch)) 1244 continue; 1245 1246 local->int_scan_req->channels[n_ch] = tmp_ch; 1247 n_ch++; 1248 } 1249 } 1250 1251 if (n_ch == 0) 1252 return -EINVAL; 1253 1254 local->int_scan_req->n_channels = n_ch; 1255 } else { 1256 for (i = 0; i < n_channels; i++) { 1257 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR | 1258 IEEE80211_CHAN_DISABLED) || 1259 !cfg80211_wdev_channel_allowed(&sdata->wdev, 1260 channels[i])) 1261 continue; 1262 1263 local->int_scan_req->channels[n_ch] = channels[i]; 1264 n_ch++; 1265 } 1266 1267 if (n_ch == 0) 1268 return -EINVAL; 1269 1270 local->int_scan_req->n_channels = n_ch; 1271 } 1272 1273 local->int_scan_req->ssids = &local->scan_ssid; 1274 local->int_scan_req->n_ssids = 1; 1275 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); 1276 local->int_scan_req->ssids[0].ssid_len = ssid_len; 1277 1278 return __ieee80211_start_scan(sdata, sdata->local->int_scan_req); 1279 } 1280 1281 void ieee80211_scan_cancel(struct ieee80211_local *local) 1282 { 1283 /* ensure a new scan cannot be queued */ 1284 lockdep_assert_wiphy(local->hw.wiphy); 1285 1286 /* 1287 * We are canceling software scan, or deferred scan that was not 1288 * yet really started (see __ieee80211_start_scan ). 1289 * 1290 * Regarding hardware scan: 1291 * - we can not call __ieee80211_scan_completed() as when 1292 * SCAN_HW_SCANNING bit is set this function change 1293 * local->hw_scan_req to operate on 5G band, what race with 1294 * driver which can use local->hw_scan_req 1295 * 1296 * - we can not cancel scan_work since driver can schedule it 1297 * by ieee80211_scan_completed(..., true) to finish scan 1298 * 1299 * Hence we only call the cancel_hw_scan() callback, but the low-level 1300 * driver is still responsible for calling ieee80211_scan_completed() 1301 * after the scan was completed/aborted. 1302 */ 1303 1304 if (!local->scan_req) 1305 return; 1306 1307 /* 1308 * We have a scan running and the driver already reported completion, 1309 * but the worker hasn't run yet or is stuck on the mutex - mark it as 1310 * cancelled. 1311 */ 1312 if (test_bit(SCAN_HW_SCANNING, &local->scanning) && 1313 test_bit(SCAN_COMPLETED, &local->scanning)) { 1314 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1315 return; 1316 } 1317 1318 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) { 1319 /* 1320 * Make sure that __ieee80211_scan_completed doesn't trigger a 1321 * scan on another band. 1322 */ 1323 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1324 if (local->ops->cancel_hw_scan) 1325 drv_cancel_hw_scan(local, 1326 rcu_dereference_protected(local->scan_sdata, 1327 lockdep_is_held(&local->hw.wiphy->mtx))); 1328 return; 1329 } 1330 1331 wiphy_delayed_work_cancel(local->hw.wiphy, &local->scan_work); 1332 /* and clean up */ 1333 memset(&local->scan_info, 0, sizeof(local->scan_info)); 1334 __ieee80211_scan_completed(&local->hw, true); 1335 } 1336 1337 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1338 struct cfg80211_sched_scan_request *req) 1339 { 1340 struct ieee80211_local *local = sdata->local; 1341 struct ieee80211_scan_ies sched_scan_ies = {}; 1342 struct cfg80211_chan_def chandef; 1343 int ret, i, iebufsz, num_bands = 0; 1344 u32 rate_masks[NUM_NL80211_BANDS] = {}; 1345 u8 bands_used = 0; 1346 u8 *ie; 1347 u32 flags = 0; 1348 1349 lockdep_assert_wiphy(local->hw.wiphy); 1350 1351 iebufsz = local->scan_ies_len + req->ie_len; 1352 1353 if (!local->ops->sched_scan_start) 1354 return -EOPNOTSUPP; 1355 1356 for (i = 0; i < NUM_NL80211_BANDS; i++) { 1357 if (local->hw.wiphy->bands[i]) { 1358 bands_used |= BIT(i); 1359 rate_masks[i] = (u32) -1; 1360 num_bands++; 1361 } 1362 } 1363 1364 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 1365 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 1366 1367 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL); 1368 if (!ie) { 1369 ret = -ENOMEM; 1370 goto out; 1371 } 1372 1373 ieee80211_prepare_scan_chandef(&chandef); 1374 1375 ret = ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz, 1376 &sched_scan_ies, req->ie, 1377 req->ie_len, bands_used, rate_masks, 1378 &chandef, flags); 1379 if (ret < 0) 1380 goto error; 1381 1382 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies); 1383 if (ret == 0) { 1384 rcu_assign_pointer(local->sched_scan_sdata, sdata); 1385 rcu_assign_pointer(local->sched_scan_req, req); 1386 } 1387 1388 error: 1389 kfree(ie); 1390 out: 1391 if (ret) { 1392 /* Clean in case of failure after HW restart or upon resume. */ 1393 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1394 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1395 } 1396 1397 return ret; 1398 } 1399 1400 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1401 struct cfg80211_sched_scan_request *req) 1402 { 1403 struct ieee80211_local *local = sdata->local; 1404 1405 lockdep_assert_wiphy(local->hw.wiphy); 1406 1407 if (rcu_access_pointer(local->sched_scan_sdata)) 1408 return -EBUSY; 1409 1410 return __ieee80211_request_sched_scan_start(sdata, req); 1411 } 1412 1413 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local) 1414 { 1415 struct ieee80211_sub_if_data *sched_scan_sdata; 1416 int ret = -ENOENT; 1417 1418 lockdep_assert_wiphy(local->hw.wiphy); 1419 1420 if (!local->ops->sched_scan_stop) 1421 return -EOPNOTSUPP; 1422 1423 /* We don't want to restart sched scan anymore. */ 1424 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1425 1426 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata, 1427 lockdep_is_held(&local->hw.wiphy->mtx)); 1428 if (sched_scan_sdata) { 1429 ret = drv_sched_scan_stop(local, sched_scan_sdata); 1430 if (!ret) 1431 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1432 } 1433 1434 return ret; 1435 } 1436 1437 void ieee80211_sched_scan_results(struct ieee80211_hw *hw) 1438 { 1439 struct ieee80211_local *local = hw_to_local(hw); 1440 1441 trace_api_sched_scan_results(local); 1442 1443 cfg80211_sched_scan_results(hw->wiphy, 0); 1444 } 1445 EXPORT_SYMBOL(ieee80211_sched_scan_results); 1446 1447 void ieee80211_sched_scan_end(struct ieee80211_local *local) 1448 { 1449 lockdep_assert_wiphy(local->hw.wiphy); 1450 1451 if (!rcu_access_pointer(local->sched_scan_sdata)) 1452 return; 1453 1454 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1455 1456 /* If sched scan was aborted by the driver. */ 1457 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1458 1459 cfg80211_sched_scan_stopped_locked(local->hw.wiphy, 0); 1460 } 1461 1462 void ieee80211_sched_scan_stopped_work(struct wiphy *wiphy, 1463 struct wiphy_work *work) 1464 { 1465 struct ieee80211_local *local = 1466 container_of(work, struct ieee80211_local, 1467 sched_scan_stopped_work); 1468 1469 ieee80211_sched_scan_end(local); 1470 } 1471 1472 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw) 1473 { 1474 struct ieee80211_local *local = hw_to_local(hw); 1475 1476 trace_api_sched_scan_stopped(local); 1477 1478 /* 1479 * this shouldn't really happen, so for simplicity 1480 * simply ignore it, and let mac80211 reconfigure 1481 * the sched scan later on. 1482 */ 1483 if (local->in_reconfig) 1484 return; 1485 1486 wiphy_work_queue(hw->wiphy, &local->sched_scan_stopped_work); 1487 } 1488 EXPORT_SYMBOL(ieee80211_sched_scan_stopped); 1489