1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Scanning implementation 4 * 5 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi> 6 * Copyright 2004, Instant802 Networks, Inc. 7 * Copyright 2005, Devicescape Software, Inc. 8 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> 9 * Copyright 2007, Michael Wu <flamingice@sourmilk.net> 10 * Copyright 2013-2015 Intel Mobile Communications GmbH 11 * Copyright 2016-2017 Intel Deutschland GmbH 12 * Copyright (C) 2018-2024 Intel Corporation 13 */ 14 15 #include <linux/if_arp.h> 16 #include <linux/etherdevice.h> 17 #include <linux/rtnetlink.h> 18 #include <net/sch_generic.h> 19 #include <linux/slab.h> 20 #include <linux/export.h> 21 #include <linux/random.h> 22 #include <net/mac80211.h> 23 24 #include "ieee80211_i.h" 25 #include "driver-ops.h" 26 #include "mesh.h" 27 28 #define IEEE80211_PROBE_DELAY (HZ / 33) 29 #define IEEE80211_CHANNEL_TIME (HZ / 33) 30 #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 9) 31 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.scan_width = NL80211_BSS_CHAN_WIDTH_20; 191 if (rx_status->bw == RATE_INFO_BW_5) 192 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_5; 193 else if (rx_status->bw == RATE_INFO_BW_10) 194 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_10; 195 196 bss_meta.chan = channel; 197 198 rcu_read_lock(); 199 scan_sdata = rcu_dereference(local->scan_sdata); 200 if (scan_sdata && scan_sdata->vif.type == NL80211_IFTYPE_STATION && 201 scan_sdata->vif.cfg.assoc && 202 ieee80211_have_rx_timestamp(rx_status)) { 203 bss_meta.parent_tsf = 204 ieee80211_calculate_rx_timestamp(local, rx_status, 205 len + FCS_LEN, 24); 206 ether_addr_copy(bss_meta.parent_bssid, 207 scan_sdata->vif.bss_conf.bssid); 208 } 209 rcu_read_unlock(); 210 211 cbss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, 212 mgmt, len, GFP_ATOMIC); 213 if (!cbss) 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 return (void *)cbss->priv; 222 } 223 224 static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata, 225 struct ieee80211_channel *channel, 226 u32 scan_flags, const u8 *da) 227 { 228 if (!sdata) 229 return false; 230 231 /* accept broadcast on 6 GHz and for OCE */ 232 if (is_broadcast_ether_addr(da) && 233 (channel->band == NL80211_BAND_6GHZ || 234 scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP)) 235 return true; 236 237 if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 238 return true; 239 return ether_addr_equal(da, sdata->vif.addr); 240 } 241 242 void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb) 243 { 244 struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); 245 struct ieee80211_sub_if_data *sdata1, *sdata2; 246 struct ieee80211_mgmt *mgmt = (void *)skb->data; 247 struct ieee80211_bss *bss; 248 struct ieee80211_channel *channel; 249 size_t min_hdr_len = offsetof(struct ieee80211_mgmt, 250 u.probe_resp.variable); 251 252 if (!ieee80211_is_probe_resp(mgmt->frame_control) && 253 !ieee80211_is_beacon(mgmt->frame_control) && 254 !ieee80211_is_s1g_beacon(mgmt->frame_control)) 255 return; 256 257 if (ieee80211_is_s1g_beacon(mgmt->frame_control)) { 258 if (ieee80211_is_s1g_short_beacon(mgmt->frame_control)) 259 min_hdr_len = offsetof(struct ieee80211_ext, 260 u.s1g_short_beacon.variable); 261 else 262 min_hdr_len = offsetof(struct ieee80211_ext, 263 u.s1g_beacon); 264 } 265 266 if (skb->len < min_hdr_len) 267 return; 268 269 sdata1 = rcu_dereference(local->scan_sdata); 270 sdata2 = rcu_dereference(local->sched_scan_sdata); 271 272 if (likely(!sdata1 && !sdata2)) 273 return; 274 275 if (test_and_clear_bit(SCAN_BEACON_WAIT, &local->scanning)) { 276 /* 277 * we were passive scanning because of radar/no-IR, but 278 * the beacon/proberesp rx gives us an opportunity to upgrade 279 * to active scan 280 */ 281 set_bit(SCAN_BEACON_DONE, &local->scanning); 282 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 0); 283 } 284 285 channel = ieee80211_get_channel_khz(local->hw.wiphy, 286 ieee80211_rx_status_to_khz(rx_status)); 287 288 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 289 return; 290 291 if (ieee80211_is_probe_resp(mgmt->frame_control)) { 292 struct cfg80211_scan_request *scan_req; 293 struct cfg80211_sched_scan_request *sched_scan_req; 294 u32 scan_req_flags = 0, sched_scan_req_flags = 0; 295 296 scan_req = rcu_dereference(local->scan_req); 297 sched_scan_req = rcu_dereference(local->sched_scan_req); 298 299 if (scan_req) 300 scan_req_flags = scan_req->flags; 301 302 if (sched_scan_req) 303 sched_scan_req_flags = sched_scan_req->flags; 304 305 /* ignore ProbeResp to foreign address or non-bcast (OCE) 306 * unless scanning with randomised address 307 */ 308 if (!ieee80211_scan_accept_presp(sdata1, channel, 309 scan_req_flags, 310 mgmt->da) && 311 !ieee80211_scan_accept_presp(sdata2, channel, 312 sched_scan_req_flags, 313 mgmt->da)) 314 return; 315 } 316 317 bss = ieee80211_bss_info_update(local, rx_status, 318 mgmt, skb->len, 319 channel); 320 if (bss) 321 ieee80211_rx_bss_put(local, bss); 322 } 323 324 static void 325 ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef, 326 enum nl80211_bss_scan_width scan_width) 327 { 328 memset(chandef, 0, sizeof(*chandef)); 329 switch (scan_width) { 330 case NL80211_BSS_CHAN_WIDTH_5: 331 chandef->width = NL80211_CHAN_WIDTH_5; 332 break; 333 case NL80211_BSS_CHAN_WIDTH_10: 334 chandef->width = NL80211_CHAN_WIDTH_10; 335 break; 336 default: 337 chandef->width = NL80211_CHAN_WIDTH_20_NOHT; 338 break; 339 } 340 } 341 342 /* return false if no more work */ 343 static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data *sdata) 344 { 345 struct ieee80211_local *local = sdata->local; 346 struct cfg80211_scan_request *req; 347 struct cfg80211_chan_def chandef; 348 u8 bands_used = 0; 349 int i, ielen, n_chans; 350 u32 flags = 0; 351 352 req = rcu_dereference_protected(local->scan_req, 353 lockdep_is_held(&local->mtx)); 354 355 if (test_bit(SCAN_HW_CANCELLED, &local->scanning)) 356 return false; 357 358 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 359 for (i = 0; i < req->n_channels; i++) { 360 local->hw_scan_req->req.channels[i] = req->channels[i]; 361 bands_used |= BIT(req->channels[i]->band); 362 } 363 364 n_chans = req->n_channels; 365 } else { 366 do { 367 if (local->hw_scan_band == NUM_NL80211_BANDS) 368 return false; 369 370 n_chans = 0; 371 372 for (i = 0; i < req->n_channels; i++) { 373 if (req->channels[i]->band != 374 local->hw_scan_band) 375 continue; 376 local->hw_scan_req->req.channels[n_chans] = 377 req->channels[i]; 378 n_chans++; 379 bands_used |= BIT(req->channels[i]->band); 380 } 381 382 local->hw_scan_band++; 383 } while (!n_chans); 384 } 385 386 local->hw_scan_req->req.n_channels = n_chans; 387 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 388 389 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 390 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 391 392 ielen = ieee80211_build_preq_ies(sdata, 393 (u8 *)local->hw_scan_req->req.ie, 394 local->hw_scan_ies_bufsize, 395 &local->hw_scan_req->ies, 396 req->ie, req->ie_len, 397 bands_used, req->rates, &chandef, 398 flags); 399 local->hw_scan_req->req.ie_len = ielen; 400 local->hw_scan_req->req.no_cck = req->no_cck; 401 ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr); 402 ether_addr_copy(local->hw_scan_req->req.mac_addr_mask, 403 req->mac_addr_mask); 404 ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid); 405 406 return true; 407 } 408 409 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) 410 { 411 struct ieee80211_local *local = hw_to_local(hw); 412 bool hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); 413 bool was_scanning = local->scanning; 414 struct cfg80211_scan_request *scan_req; 415 struct ieee80211_sub_if_data *scan_sdata; 416 struct ieee80211_sub_if_data *sdata; 417 418 lockdep_assert_held(&local->mtx); 419 420 /* 421 * It's ok to abort a not-yet-running scan (that 422 * we have one at all will be verified by checking 423 * local->scan_req next), but not to complete it 424 * successfully. 425 */ 426 if (WARN_ON(!local->scanning && !aborted)) 427 aborted = true; 428 429 if (WARN_ON(!local->scan_req)) 430 return; 431 432 scan_sdata = rcu_dereference_protected(local->scan_sdata, 433 lockdep_is_held(&local->mtx)); 434 435 if (hw_scan && !aborted && 436 !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) && 437 ieee80211_prep_hw_scan(scan_sdata)) { 438 int rc; 439 440 rc = drv_hw_scan(local, 441 rcu_dereference_protected(local->scan_sdata, 442 lockdep_is_held(&local->mtx)), 443 local->hw_scan_req); 444 445 if (rc == 0) 446 return; 447 448 /* HW scan failed and is going to be reported as aborted, 449 * so clear old scan info. 450 */ 451 memset(&local->scan_info, 0, sizeof(local->scan_info)); 452 aborted = true; 453 } 454 455 kfree(local->hw_scan_req); 456 local->hw_scan_req = NULL; 457 458 scan_req = rcu_dereference_protected(local->scan_req, 459 lockdep_is_held(&local->mtx)); 460 461 RCU_INIT_POINTER(local->scan_req, NULL); 462 RCU_INIT_POINTER(local->scan_sdata, NULL); 463 464 local->scanning = 0; 465 local->scan_chandef.chan = NULL; 466 467 synchronize_rcu(); 468 469 if (scan_req != local->int_scan_req) { 470 local->scan_info.aborted = aborted; 471 cfg80211_scan_done(scan_req, &local->scan_info); 472 } 473 474 /* Set power back to normal operating levels. */ 475 ieee80211_hw_config(local, 0); 476 477 if (!hw_scan && was_scanning) { 478 ieee80211_configure_filter(local); 479 drv_sw_scan_complete(local, scan_sdata); 480 ieee80211_offchannel_return(local); 481 } 482 483 ieee80211_recalc_idle(local); 484 485 ieee80211_mlme_notify_scan_completed(local); 486 ieee80211_ibss_notify_scan_completed(local); 487 488 /* Requeue all the work that might have been ignored while 489 * the scan was in progress; if there was none this will 490 * just be a no-op for the particular interface. 491 */ 492 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 493 if (ieee80211_sdata_running(sdata)) 494 wiphy_work_queue(sdata->local->hw.wiphy, &sdata->work); 495 } 496 497 if (was_scanning) 498 ieee80211_start_next_roc(local); 499 } 500 501 void ieee80211_scan_completed(struct ieee80211_hw *hw, 502 struct cfg80211_scan_info *info) 503 { 504 struct ieee80211_local *local = hw_to_local(hw); 505 506 trace_api_scan_completed(local, info->aborted); 507 508 set_bit(SCAN_COMPLETED, &local->scanning); 509 if (info->aborted) 510 set_bit(SCAN_ABORTED, &local->scanning); 511 512 memcpy(&local->scan_info, info, sizeof(*info)); 513 514 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 0); 515 } 516 EXPORT_SYMBOL(ieee80211_scan_completed); 517 518 static int ieee80211_start_sw_scan(struct ieee80211_local *local, 519 struct ieee80211_sub_if_data *sdata) 520 { 521 /* Software scan is not supported in multi-channel cases */ 522 if (local->use_chanctx) 523 return -EOPNOTSUPP; 524 525 /* 526 * Hardware/driver doesn't support hw_scan, so use software 527 * scanning instead. First send a nullfunc frame with power save 528 * bit on so that AP will buffer the frames for us while we are not 529 * listening, then send probe requests to each channel and wait for 530 * the responses. After all channels are scanned, tune back to the 531 * original channel and send a nullfunc frame with power save bit 532 * off to trigger the AP to send us all the buffered frames. 533 * 534 * Note that while local->sw_scanning is true everything else but 535 * nullfunc frames and probe requests will be dropped in 536 * ieee80211_tx_h_check_assoc(). 537 */ 538 drv_sw_scan_start(local, sdata, local->scan_addr); 539 540 local->leave_oper_channel_time = jiffies; 541 local->next_scan_state = SCAN_DECISION; 542 local->scan_channel_idx = 0; 543 544 ieee80211_offchannel_stop_vifs(local); 545 546 /* ensure nullfunc is transmitted before leaving operating channel */ 547 ieee80211_flush_queues(local, NULL, false); 548 549 ieee80211_configure_filter(local); 550 551 /* We need to set power level at maximum rate for scanning. */ 552 ieee80211_hw_config(local, 0); 553 554 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 0); 555 556 return 0; 557 } 558 559 static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata) 560 { 561 struct ieee80211_local *local = sdata->local; 562 struct ieee80211_sub_if_data *sdata_iter; 563 564 if (!ieee80211_is_radar_required(local)) 565 return true; 566 567 if (!regulatory_pre_cac_allowed(local->hw.wiphy)) 568 return false; 569 570 mutex_lock(&local->iflist_mtx); 571 list_for_each_entry(sdata_iter, &local->interfaces, list) { 572 if (sdata_iter->wdev.cac_started) { 573 mutex_unlock(&local->iflist_mtx); 574 return false; 575 } 576 } 577 mutex_unlock(&local->iflist_mtx); 578 579 return true; 580 } 581 582 static bool ieee80211_can_scan(struct ieee80211_local *local, 583 struct ieee80211_sub_if_data *sdata) 584 { 585 if (!__ieee80211_can_leave_ch(sdata)) 586 return false; 587 588 if (!list_empty(&local->roc_list)) 589 return false; 590 591 if (sdata->vif.type == NL80211_IFTYPE_STATION && 592 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL) 593 return false; 594 595 return true; 596 } 597 598 void ieee80211_run_deferred_scan(struct ieee80211_local *local) 599 { 600 lockdep_assert_held(&local->mtx); 601 602 if (!local->scan_req || local->scanning) 603 return; 604 605 if (!ieee80211_can_scan(local, 606 rcu_dereference_protected( 607 local->scan_sdata, 608 lockdep_is_held(&local->mtx)))) 609 return; 610 611 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 612 round_jiffies_relative(0)); 613 } 614 615 static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata, 616 const u8 *src, const u8 *dst, 617 const u8 *ssid, size_t ssid_len, 618 const u8 *ie, size_t ie_len, 619 u32 ratemask, u32 flags, u32 tx_flags, 620 struct ieee80211_channel *channel) 621 { 622 struct sk_buff *skb; 623 624 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel, 625 ssid, ssid_len, 626 ie, ie_len, flags); 627 628 if (skb) { 629 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) { 630 struct ieee80211_hdr *hdr = (void *)skb->data; 631 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 632 u16 sn = get_random_u16(); 633 634 info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO; 635 hdr->seq_ctrl = 636 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn)); 637 } 638 IEEE80211_SKB_CB(skb)->flags |= tx_flags; 639 IEEE80211_SKB_CB(skb)->control.flags |= IEEE80211_TX_CTRL_SCAN_TX; 640 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band); 641 } 642 } 643 644 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, 645 unsigned long *next_delay) 646 { 647 int i; 648 struct ieee80211_sub_if_data *sdata; 649 struct cfg80211_scan_request *scan_req; 650 enum nl80211_band band = local->hw.conf.chandef.chan->band; 651 u32 flags = 0, tx_flags; 652 653 scan_req = rcu_dereference_protected(local->scan_req, 654 lockdep_is_held(&local->mtx)); 655 656 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK; 657 if (scan_req->no_cck) 658 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE; 659 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 660 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 661 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN) 662 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN; 663 664 sdata = rcu_dereference_protected(local->scan_sdata, 665 lockdep_is_held(&local->mtx)); 666 667 for (i = 0; i < scan_req->n_ssids; i++) 668 ieee80211_send_scan_probe_req( 669 sdata, local->scan_addr, scan_req->bssid, 670 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len, 671 scan_req->ie, scan_req->ie_len, 672 scan_req->rates[band], flags, 673 tx_flags, local->hw.conf.chandef.chan); 674 675 /* 676 * After sending probe requests, wait for probe responses 677 * on the channel. 678 */ 679 *next_delay = IEEE80211_CHANNEL_TIME; 680 local->next_scan_state = SCAN_DECISION; 681 } 682 683 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, 684 struct cfg80211_scan_request *req) 685 { 686 struct ieee80211_local *local = sdata->local; 687 bool hw_scan = local->ops->hw_scan; 688 int rc; 689 690 lockdep_assert_held(&local->mtx); 691 692 if (local->scan_req) 693 return -EBUSY; 694 695 if (!__ieee80211_can_leave_ch(sdata)) 696 return -EBUSY; 697 698 if (!ieee80211_can_scan(local, sdata)) { 699 /* wait for the work to finish/time out */ 700 rcu_assign_pointer(local->scan_req, req); 701 rcu_assign_pointer(local->scan_sdata, sdata); 702 return 0; 703 } 704 705 again: 706 if (hw_scan) { 707 u8 *ies; 708 709 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len; 710 711 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 712 int i, n_bands = 0; 713 u8 bands_counted = 0; 714 715 for (i = 0; i < req->n_channels; i++) { 716 if (bands_counted & BIT(req->channels[i]->band)) 717 continue; 718 bands_counted |= BIT(req->channels[i]->band); 719 n_bands++; 720 } 721 722 local->hw_scan_ies_bufsize *= n_bands; 723 } 724 725 local->hw_scan_req = kmalloc(struct_size(local->hw_scan_req, 726 req.channels, 727 req->n_channels) + 728 local->hw_scan_ies_bufsize, 729 GFP_KERNEL); 730 if (!local->hw_scan_req) 731 return -ENOMEM; 732 733 local->hw_scan_req->req.ssids = req->ssids; 734 local->hw_scan_req->req.n_ssids = req->n_ssids; 735 /* None of the channels are actually set 736 * up but let UBSAN know the boundaries. 737 */ 738 local->hw_scan_req->req.n_channels = req->n_channels; 739 740 ies = (u8 *)local->hw_scan_req + 741 sizeof(*local->hw_scan_req) + 742 req->n_channels * sizeof(req->channels[0]); 743 local->hw_scan_req->req.ie = ies; 744 local->hw_scan_req->req.flags = req->flags; 745 eth_broadcast_addr(local->hw_scan_req->req.bssid); 746 local->hw_scan_req->req.duration = req->duration; 747 local->hw_scan_req->req.duration_mandatory = 748 req->duration_mandatory; 749 750 local->hw_scan_band = 0; 751 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params; 752 local->hw_scan_req->req.scan_6ghz_params = 753 req->scan_6ghz_params; 754 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz; 755 756 /* 757 * After allocating local->hw_scan_req, we must 758 * go through until ieee80211_prep_hw_scan(), so 759 * anything that might be changed here and leave 760 * this function early must not go after this 761 * allocation. 762 */ 763 } 764 765 rcu_assign_pointer(local->scan_req, req); 766 rcu_assign_pointer(local->scan_sdata, sdata); 767 768 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 769 get_random_mask_addr(local->scan_addr, 770 req->mac_addr, 771 req->mac_addr_mask); 772 else 773 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN); 774 775 if (hw_scan) { 776 __set_bit(SCAN_HW_SCANNING, &local->scanning); 777 } else if ((req->n_channels == 1) && 778 (req->channels[0] == local->_oper_chandef.chan)) { 779 /* 780 * If we are scanning only on the operating channel 781 * then we do not need to stop normal activities 782 */ 783 unsigned long next_delay; 784 785 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning); 786 787 ieee80211_recalc_idle(local); 788 789 /* Notify driver scan is starting, keep order of operations 790 * same as normal software scan, in case that matters. */ 791 drv_sw_scan_start(local, sdata, local->scan_addr); 792 793 ieee80211_configure_filter(local); /* accept probe-responses */ 794 795 /* We need to ensure power level is at max for scanning. */ 796 ieee80211_hw_config(local, 0); 797 798 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR | 799 IEEE80211_CHAN_RADAR)) || 800 !req->n_ssids) { 801 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 802 if (req->n_ssids) 803 set_bit(SCAN_BEACON_WAIT, &local->scanning); 804 } else { 805 ieee80211_scan_state_send_probe(local, &next_delay); 806 next_delay = IEEE80211_CHANNEL_TIME; 807 } 808 809 /* Now, just wait a bit and we are all done! */ 810 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 811 next_delay); 812 return 0; 813 } else { 814 /* Do normal software scan */ 815 __set_bit(SCAN_SW_SCANNING, &local->scanning); 816 } 817 818 ieee80211_recalc_idle(local); 819 820 if (hw_scan) { 821 WARN_ON(!ieee80211_prep_hw_scan(sdata)); 822 rc = drv_hw_scan(local, sdata, local->hw_scan_req); 823 } else { 824 rc = ieee80211_start_sw_scan(local, sdata); 825 } 826 827 if (rc) { 828 kfree(local->hw_scan_req); 829 local->hw_scan_req = NULL; 830 local->scanning = 0; 831 832 ieee80211_recalc_idle(local); 833 834 local->scan_req = NULL; 835 RCU_INIT_POINTER(local->scan_sdata, NULL); 836 } 837 838 if (hw_scan && rc == 1) { 839 /* 840 * we can't fall back to software for P2P-GO 841 * as it must update NoA etc. 842 */ 843 if (ieee80211_vif_type_p2p(&sdata->vif) == 844 NL80211_IFTYPE_P2P_GO) 845 return -EOPNOTSUPP; 846 hw_scan = false; 847 goto again; 848 } 849 850 return rc; 851 } 852 853 static unsigned long 854 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) 855 { 856 /* 857 * TODO: channel switching also consumes quite some time, 858 * add that delay as well to get a better estimation 859 */ 860 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) 861 return IEEE80211_PASSIVE_CHANNEL_TIME; 862 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; 863 } 864 865 static void ieee80211_scan_state_decision(struct ieee80211_local *local, 866 unsigned long *next_delay) 867 { 868 bool associated = false; 869 bool tx_empty = true; 870 bool bad_latency; 871 struct ieee80211_sub_if_data *sdata; 872 struct ieee80211_channel *next_chan; 873 enum mac80211_scan_state next_scan_state; 874 struct cfg80211_scan_request *scan_req; 875 876 /* 877 * check if at least one STA interface is associated, 878 * check if at least one STA interface has pending tx frames 879 * and grab the lowest used beacon interval 880 */ 881 mutex_lock(&local->iflist_mtx); 882 list_for_each_entry(sdata, &local->interfaces, list) { 883 if (!ieee80211_sdata_running(sdata)) 884 continue; 885 886 if (sdata->vif.type == NL80211_IFTYPE_STATION) { 887 if (sdata->u.mgd.associated) { 888 associated = true; 889 890 if (!qdisc_all_tx_empty(sdata->dev)) { 891 tx_empty = false; 892 break; 893 } 894 } 895 } 896 } 897 mutex_unlock(&local->iflist_mtx); 898 899 scan_req = rcu_dereference_protected(local->scan_req, 900 lockdep_is_held(&local->mtx)); 901 902 next_chan = scan_req->channels[local->scan_channel_idx]; 903 904 /* 905 * we're currently scanning a different channel, let's 906 * see if we can scan another channel without interfering 907 * with the current traffic situation. 908 * 909 * Keep good latency, do not stay off-channel more than 125 ms. 910 */ 911 912 bad_latency = time_after(jiffies + 913 ieee80211_scan_get_channel_time(next_chan), 914 local->leave_oper_channel_time + HZ / 8); 915 916 if (associated && !tx_empty) { 917 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY) 918 next_scan_state = SCAN_ABORT; 919 else 920 next_scan_state = SCAN_SUSPEND; 921 } else if (associated && bad_latency) { 922 next_scan_state = SCAN_SUSPEND; 923 } else { 924 next_scan_state = SCAN_SET_CHANNEL; 925 } 926 927 local->next_scan_state = next_scan_state; 928 929 *next_delay = 0; 930 } 931 932 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, 933 unsigned long *next_delay) 934 { 935 int skip; 936 struct ieee80211_channel *chan; 937 enum nl80211_bss_scan_width oper_scan_width; 938 struct cfg80211_scan_request *scan_req; 939 940 scan_req = rcu_dereference_protected(local->scan_req, 941 lockdep_is_held(&local->mtx)); 942 943 skip = 0; 944 chan = scan_req->channels[local->scan_channel_idx]; 945 946 local->scan_chandef.chan = chan; 947 local->scan_chandef.center_freq1 = chan->center_freq; 948 local->scan_chandef.freq1_offset = chan->freq_offset; 949 local->scan_chandef.center_freq2 = 0; 950 951 /* For scanning on the S1G band, ignore scan_width (which is constant 952 * across all channels) for now since channel width is specific to each 953 * channel. Detect the required channel width here and likely revisit 954 * later. Maybe scan_width could be used to build the channel scan list? 955 */ 956 if (chan->band == NL80211_BAND_S1GHZ) { 957 local->scan_chandef.width = ieee80211_s1g_channel_width(chan); 958 goto set_channel; 959 } 960 961 switch (scan_req->scan_width) { 962 case NL80211_BSS_CHAN_WIDTH_5: 963 local->scan_chandef.width = NL80211_CHAN_WIDTH_5; 964 break; 965 case NL80211_BSS_CHAN_WIDTH_10: 966 local->scan_chandef.width = NL80211_CHAN_WIDTH_10; 967 break; 968 default: 969 case NL80211_BSS_CHAN_WIDTH_20: 970 /* If scanning on oper channel, use whatever channel-type 971 * is currently in use. 972 */ 973 oper_scan_width = cfg80211_chandef_to_scan_width( 974 &local->_oper_chandef); 975 if (chan == local->_oper_chandef.chan && 976 oper_scan_width == scan_req->scan_width) 977 local->scan_chandef = local->_oper_chandef; 978 else 979 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT; 980 break; 981 case NL80211_BSS_CHAN_WIDTH_1: 982 case NL80211_BSS_CHAN_WIDTH_2: 983 /* shouldn't get here, S1G handled above */ 984 WARN_ON(1); 985 break; 986 } 987 988 set_channel: 989 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) 990 skip = 1; 991 992 /* advance state machine to next channel/band */ 993 local->scan_channel_idx++; 994 995 if (skip) { 996 /* if we skip this channel return to the decision state */ 997 local->next_scan_state = SCAN_DECISION; 998 return; 999 } 1000 1001 /* 1002 * Probe delay is used to update the NAV, cf. 11.1.3.2.2 1003 * (which unfortunately doesn't say _why_ step a) is done, 1004 * but it waits for the probe delay or until a frame is 1005 * received - and the received frame would update the NAV). 1006 * For now, we do not support waiting until a frame is 1007 * received. 1008 * 1009 * In any case, it is not necessary for a passive scan. 1010 */ 1011 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) || 1012 !scan_req->n_ssids) { 1013 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 1014 local->next_scan_state = SCAN_DECISION; 1015 if (scan_req->n_ssids) 1016 set_bit(SCAN_BEACON_WAIT, &local->scanning); 1017 return; 1018 } 1019 1020 /* active scan, send probes */ 1021 *next_delay = IEEE80211_PROBE_DELAY; 1022 local->next_scan_state = SCAN_SEND_PROBE; 1023 } 1024 1025 static void ieee80211_scan_state_suspend(struct ieee80211_local *local, 1026 unsigned long *next_delay) 1027 { 1028 /* switch back to the operating channel */ 1029 local->scan_chandef.chan = NULL; 1030 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 1031 1032 /* disable PS */ 1033 ieee80211_offchannel_return(local); 1034 1035 *next_delay = HZ / 5; 1036 /* afterwards, resume scan & go to next channel */ 1037 local->next_scan_state = SCAN_RESUME; 1038 } 1039 1040 static void ieee80211_scan_state_resume(struct ieee80211_local *local, 1041 unsigned long *next_delay) 1042 { 1043 ieee80211_offchannel_stop_vifs(local); 1044 1045 if (local->ops->flush) { 1046 ieee80211_flush_queues(local, NULL, false); 1047 *next_delay = 0; 1048 } else 1049 *next_delay = HZ / 10; 1050 1051 /* remember when we left the operating channel */ 1052 local->leave_oper_channel_time = jiffies; 1053 1054 /* advance to the next channel to be scanned */ 1055 local->next_scan_state = SCAN_SET_CHANNEL; 1056 } 1057 1058 void ieee80211_scan_work(struct wiphy *wiphy, struct wiphy_work *work) 1059 { 1060 struct ieee80211_local *local = 1061 container_of(work, struct ieee80211_local, scan_work.work); 1062 struct ieee80211_sub_if_data *sdata; 1063 struct cfg80211_scan_request *scan_req; 1064 unsigned long next_delay = 0; 1065 bool aborted; 1066 1067 mutex_lock(&local->mtx); 1068 1069 if (!ieee80211_can_run_worker(local)) { 1070 aborted = true; 1071 goto out_complete; 1072 } 1073 1074 sdata = rcu_dereference_protected(local->scan_sdata, 1075 lockdep_is_held(&local->mtx)); 1076 scan_req = rcu_dereference_protected(local->scan_req, 1077 lockdep_is_held(&local->mtx)); 1078 1079 /* When scanning on-channel, the first-callback means completed. */ 1080 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) { 1081 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1082 goto out_complete; 1083 } 1084 1085 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) { 1086 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1087 goto out_complete; 1088 } 1089 1090 if (!sdata || !scan_req) 1091 goto out; 1092 1093 if (!local->scanning) { 1094 int rc; 1095 1096 RCU_INIT_POINTER(local->scan_req, NULL); 1097 RCU_INIT_POINTER(local->scan_sdata, NULL); 1098 1099 rc = __ieee80211_start_scan(sdata, scan_req); 1100 if (rc) { 1101 /* need to complete scan in cfg80211 */ 1102 rcu_assign_pointer(local->scan_req, scan_req); 1103 aborted = true; 1104 goto out_complete; 1105 } else 1106 goto out; 1107 } 1108 1109 clear_bit(SCAN_BEACON_WAIT, &local->scanning); 1110 1111 /* 1112 * as long as no delay is required advance immediately 1113 * without scheduling a new work 1114 */ 1115 do { 1116 if (!ieee80211_sdata_running(sdata)) { 1117 aborted = true; 1118 goto out_complete; 1119 } 1120 1121 if (test_and_clear_bit(SCAN_BEACON_DONE, &local->scanning) && 1122 local->next_scan_state == SCAN_DECISION) 1123 local->next_scan_state = SCAN_SEND_PROBE; 1124 1125 switch (local->next_scan_state) { 1126 case SCAN_DECISION: 1127 /* if no more bands/channels left, complete scan */ 1128 if (local->scan_channel_idx >= scan_req->n_channels) { 1129 aborted = false; 1130 goto out_complete; 1131 } 1132 ieee80211_scan_state_decision(local, &next_delay); 1133 break; 1134 case SCAN_SET_CHANNEL: 1135 ieee80211_scan_state_set_channel(local, &next_delay); 1136 break; 1137 case SCAN_SEND_PROBE: 1138 ieee80211_scan_state_send_probe(local, &next_delay); 1139 break; 1140 case SCAN_SUSPEND: 1141 ieee80211_scan_state_suspend(local, &next_delay); 1142 break; 1143 case SCAN_RESUME: 1144 ieee80211_scan_state_resume(local, &next_delay); 1145 break; 1146 case SCAN_ABORT: 1147 aborted = true; 1148 goto out_complete; 1149 } 1150 } while (next_delay == 0); 1151 1152 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 1153 next_delay); 1154 goto out; 1155 1156 out_complete: 1157 __ieee80211_scan_completed(&local->hw, aborted); 1158 out: 1159 mutex_unlock(&local->mtx); 1160 } 1161 1162 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, 1163 struct cfg80211_scan_request *req) 1164 { 1165 int res; 1166 1167 mutex_lock(&sdata->local->mtx); 1168 res = __ieee80211_start_scan(sdata, req); 1169 mutex_unlock(&sdata->local->mtx); 1170 1171 return res; 1172 } 1173 1174 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata, 1175 const u8 *ssid, u8 ssid_len, 1176 struct ieee80211_channel **channels, 1177 unsigned int n_channels, 1178 enum nl80211_bss_scan_width scan_width) 1179 { 1180 struct ieee80211_local *local = sdata->local; 1181 int ret = -EBUSY, i, n_ch = 0; 1182 enum nl80211_band band; 1183 1184 mutex_lock(&local->mtx); 1185 1186 /* busy scanning */ 1187 if (local->scan_req) 1188 goto unlock; 1189 1190 /* fill internal scan request */ 1191 if (!channels) { 1192 int max_n; 1193 1194 for (band = 0; band < NUM_NL80211_BANDS; band++) { 1195 if (!local->hw.wiphy->bands[band] || 1196 band == NL80211_BAND_6GHZ) 1197 continue; 1198 1199 max_n = local->hw.wiphy->bands[band]->n_channels; 1200 for (i = 0; i < max_n; i++) { 1201 struct ieee80211_channel *tmp_ch = 1202 &local->hw.wiphy->bands[band]->channels[i]; 1203 1204 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR | 1205 IEEE80211_CHAN_DISABLED)) 1206 continue; 1207 1208 local->int_scan_req->channels[n_ch] = tmp_ch; 1209 n_ch++; 1210 } 1211 } 1212 1213 if (WARN_ON_ONCE(n_ch == 0)) 1214 goto unlock; 1215 1216 local->int_scan_req->n_channels = n_ch; 1217 } else { 1218 for (i = 0; i < n_channels; i++) { 1219 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR | 1220 IEEE80211_CHAN_DISABLED)) 1221 continue; 1222 1223 local->int_scan_req->channels[n_ch] = channels[i]; 1224 n_ch++; 1225 } 1226 1227 if (WARN_ON_ONCE(n_ch == 0)) 1228 goto unlock; 1229 1230 local->int_scan_req->n_channels = n_ch; 1231 } 1232 1233 local->int_scan_req->ssids = &local->scan_ssid; 1234 local->int_scan_req->n_ssids = 1; 1235 local->int_scan_req->scan_width = scan_width; 1236 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); 1237 local->int_scan_req->ssids[0].ssid_len = ssid_len; 1238 1239 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); 1240 unlock: 1241 mutex_unlock(&local->mtx); 1242 return ret; 1243 } 1244 1245 void ieee80211_scan_cancel(struct ieee80211_local *local) 1246 { 1247 /* ensure a new scan cannot be queued */ 1248 lockdep_assert_wiphy(local->hw.wiphy); 1249 1250 /* 1251 * We are canceling software scan, or deferred scan that was not 1252 * yet really started (see __ieee80211_start_scan ). 1253 * 1254 * Regarding hardware scan: 1255 * - we can not call __ieee80211_scan_completed() as when 1256 * SCAN_HW_SCANNING bit is set this function change 1257 * local->hw_scan_req to operate on 5G band, what race with 1258 * driver which can use local->hw_scan_req 1259 * 1260 * - we can not cancel scan_work since driver can schedule it 1261 * by ieee80211_scan_completed(..., true) to finish scan 1262 * 1263 * Hence we only call the cancel_hw_scan() callback, but the low-level 1264 * driver is still responsible for calling ieee80211_scan_completed() 1265 * after the scan was completed/aborted. 1266 */ 1267 1268 mutex_lock(&local->mtx); 1269 if (!local->scan_req) 1270 goto out; 1271 1272 /* 1273 * We have a scan running and the driver already reported completion, 1274 * but the worker hasn't run yet or is stuck on the mutex - mark it as 1275 * cancelled. 1276 */ 1277 if (test_bit(SCAN_HW_SCANNING, &local->scanning) && 1278 test_bit(SCAN_COMPLETED, &local->scanning)) { 1279 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1280 goto out; 1281 } 1282 1283 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) { 1284 /* 1285 * Make sure that __ieee80211_scan_completed doesn't trigger a 1286 * scan on another band. 1287 */ 1288 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1289 if (local->ops->cancel_hw_scan) 1290 drv_cancel_hw_scan(local, 1291 rcu_dereference_protected(local->scan_sdata, 1292 lockdep_is_held(&local->mtx))); 1293 goto out; 1294 } 1295 1296 wiphy_delayed_work_cancel(local->hw.wiphy, &local->scan_work); 1297 /* and clean up */ 1298 memset(&local->scan_info, 0, sizeof(local->scan_info)); 1299 __ieee80211_scan_completed(&local->hw, true); 1300 out: 1301 mutex_unlock(&local->mtx); 1302 } 1303 1304 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1305 struct cfg80211_sched_scan_request *req) 1306 { 1307 struct ieee80211_local *local = sdata->local; 1308 struct ieee80211_scan_ies sched_scan_ies = {}; 1309 struct cfg80211_chan_def chandef; 1310 int ret, i, iebufsz, num_bands = 0; 1311 u32 rate_masks[NUM_NL80211_BANDS] = {}; 1312 u8 bands_used = 0; 1313 u8 *ie; 1314 u32 flags = 0; 1315 1316 iebufsz = local->scan_ies_len + req->ie_len; 1317 1318 lockdep_assert_held(&local->mtx); 1319 1320 if (!local->ops->sched_scan_start) 1321 return -ENOTSUPP; 1322 1323 for (i = 0; i < NUM_NL80211_BANDS; i++) { 1324 if (local->hw.wiphy->bands[i]) { 1325 bands_used |= BIT(i); 1326 rate_masks[i] = (u32) -1; 1327 num_bands++; 1328 } 1329 } 1330 1331 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 1332 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 1333 1334 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL); 1335 if (!ie) { 1336 ret = -ENOMEM; 1337 goto out; 1338 } 1339 1340 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 1341 1342 ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz, 1343 &sched_scan_ies, req->ie, 1344 req->ie_len, bands_used, rate_masks, &chandef, 1345 flags); 1346 1347 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies); 1348 if (ret == 0) { 1349 rcu_assign_pointer(local->sched_scan_sdata, sdata); 1350 rcu_assign_pointer(local->sched_scan_req, req); 1351 } 1352 1353 kfree(ie); 1354 1355 out: 1356 if (ret) { 1357 /* Clean in case of failure after HW restart or upon resume. */ 1358 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1359 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1360 } 1361 1362 return ret; 1363 } 1364 1365 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1366 struct cfg80211_sched_scan_request *req) 1367 { 1368 struct ieee80211_local *local = sdata->local; 1369 int ret; 1370 1371 mutex_lock(&local->mtx); 1372 1373 if (rcu_access_pointer(local->sched_scan_sdata)) { 1374 mutex_unlock(&local->mtx); 1375 return -EBUSY; 1376 } 1377 1378 ret = __ieee80211_request_sched_scan_start(sdata, req); 1379 1380 mutex_unlock(&local->mtx); 1381 return ret; 1382 } 1383 1384 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local) 1385 { 1386 struct ieee80211_sub_if_data *sched_scan_sdata; 1387 int ret = -ENOENT; 1388 1389 mutex_lock(&local->mtx); 1390 1391 if (!local->ops->sched_scan_stop) { 1392 ret = -ENOTSUPP; 1393 goto out; 1394 } 1395 1396 /* We don't want to restart sched scan anymore. */ 1397 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1398 1399 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata, 1400 lockdep_is_held(&local->mtx)); 1401 if (sched_scan_sdata) { 1402 ret = drv_sched_scan_stop(local, sched_scan_sdata); 1403 if (!ret) 1404 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1405 } 1406 out: 1407 mutex_unlock(&local->mtx); 1408 1409 return ret; 1410 } 1411 1412 void ieee80211_sched_scan_results(struct ieee80211_hw *hw) 1413 { 1414 struct ieee80211_local *local = hw_to_local(hw); 1415 1416 trace_api_sched_scan_results(local); 1417 1418 cfg80211_sched_scan_results(hw->wiphy, 0); 1419 } 1420 EXPORT_SYMBOL(ieee80211_sched_scan_results); 1421 1422 void ieee80211_sched_scan_end(struct ieee80211_local *local) 1423 { 1424 mutex_lock(&local->mtx); 1425 1426 if (!rcu_access_pointer(local->sched_scan_sdata)) { 1427 mutex_unlock(&local->mtx); 1428 return; 1429 } 1430 1431 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1432 1433 /* If sched scan was aborted by the driver. */ 1434 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1435 1436 mutex_unlock(&local->mtx); 1437 1438 cfg80211_sched_scan_stopped_locked(local->hw.wiphy, 0); 1439 } 1440 1441 void ieee80211_sched_scan_stopped_work(struct wiphy *wiphy, 1442 struct wiphy_work *work) 1443 { 1444 struct ieee80211_local *local = 1445 container_of(work, struct ieee80211_local, 1446 sched_scan_stopped_work); 1447 1448 ieee80211_sched_scan_end(local); 1449 } 1450 1451 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw) 1452 { 1453 struct ieee80211_local *local = hw_to_local(hw); 1454 1455 trace_api_sched_scan_stopped(local); 1456 1457 /* 1458 * this shouldn't really happen, so for simplicity 1459 * simply ignore it, and let mac80211 reconfigure 1460 * the sched scan later on. 1461 */ 1462 if (local->in_reconfig) 1463 return; 1464 1465 wiphy_work_queue(hw->wiphy, &local->sched_scan_stopped_work); 1466 } 1467 EXPORT_SYMBOL(ieee80211_sched_scan_stopped); 1468