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) 2018-2023 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 u32 scan_flags, const u8 *da) 226 { 227 if (!sdata) 228 return false; 229 /* accept broadcast for OCE */ 230 if (scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP && 231 is_broadcast_ether_addr(da)) 232 return true; 233 if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 234 return true; 235 return ether_addr_equal(da, sdata->vif.addr); 236 } 237 238 void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb) 239 { 240 struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); 241 struct ieee80211_sub_if_data *sdata1, *sdata2; 242 struct ieee80211_mgmt *mgmt = (void *)skb->data; 243 struct ieee80211_bss *bss; 244 struct ieee80211_channel *channel; 245 size_t min_hdr_len = offsetof(struct ieee80211_mgmt, 246 u.probe_resp.variable); 247 248 if (!ieee80211_is_probe_resp(mgmt->frame_control) && 249 !ieee80211_is_beacon(mgmt->frame_control) && 250 !ieee80211_is_s1g_beacon(mgmt->frame_control)) 251 return; 252 253 if (ieee80211_is_s1g_beacon(mgmt->frame_control)) { 254 if (ieee80211_is_s1g_short_beacon(mgmt->frame_control)) 255 min_hdr_len = offsetof(struct ieee80211_ext, 256 u.s1g_short_beacon.variable); 257 else 258 min_hdr_len = offsetof(struct ieee80211_ext, 259 u.s1g_beacon); 260 } 261 262 if (skb->len < min_hdr_len) 263 return; 264 265 sdata1 = rcu_dereference(local->scan_sdata); 266 sdata2 = rcu_dereference(local->sched_scan_sdata); 267 268 if (likely(!sdata1 && !sdata2)) 269 return; 270 271 if (test_and_clear_bit(SCAN_BEACON_WAIT, &local->scanning)) { 272 /* 273 * we were passive scanning because of radar/no-IR, but 274 * the beacon/proberesp rx gives us an opportunity to upgrade 275 * to active scan 276 */ 277 set_bit(SCAN_BEACON_DONE, &local->scanning); 278 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0); 279 } 280 281 if (ieee80211_is_probe_resp(mgmt->frame_control)) { 282 struct cfg80211_scan_request *scan_req; 283 struct cfg80211_sched_scan_request *sched_scan_req; 284 u32 scan_req_flags = 0, sched_scan_req_flags = 0; 285 286 scan_req = rcu_dereference(local->scan_req); 287 sched_scan_req = rcu_dereference(local->sched_scan_req); 288 289 if (scan_req) 290 scan_req_flags = scan_req->flags; 291 292 if (sched_scan_req) 293 sched_scan_req_flags = sched_scan_req->flags; 294 295 /* ignore ProbeResp to foreign address or non-bcast (OCE) 296 * unless scanning with randomised address 297 */ 298 if (!ieee80211_scan_accept_presp(sdata1, scan_req_flags, 299 mgmt->da) && 300 !ieee80211_scan_accept_presp(sdata2, sched_scan_req_flags, 301 mgmt->da)) 302 return; 303 } 304 305 channel = ieee80211_get_channel_khz(local->hw.wiphy, 306 ieee80211_rx_status_to_khz(rx_status)); 307 308 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 309 return; 310 311 bss = ieee80211_bss_info_update(local, rx_status, 312 mgmt, skb->len, 313 channel); 314 if (bss) 315 ieee80211_rx_bss_put(local, bss); 316 } 317 318 static void 319 ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef, 320 enum nl80211_bss_scan_width scan_width) 321 { 322 memset(chandef, 0, sizeof(*chandef)); 323 switch (scan_width) { 324 case NL80211_BSS_CHAN_WIDTH_5: 325 chandef->width = NL80211_CHAN_WIDTH_5; 326 break; 327 case NL80211_BSS_CHAN_WIDTH_10: 328 chandef->width = NL80211_CHAN_WIDTH_10; 329 break; 330 default: 331 chandef->width = NL80211_CHAN_WIDTH_20_NOHT; 332 break; 333 } 334 } 335 336 /* return false if no more work */ 337 static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data *sdata) 338 { 339 struct ieee80211_local *local = sdata->local; 340 struct cfg80211_scan_request *req; 341 struct cfg80211_chan_def chandef; 342 u8 bands_used = 0; 343 int i, ielen, n_chans; 344 u32 flags = 0; 345 346 req = rcu_dereference_protected(local->scan_req, 347 lockdep_is_held(&local->mtx)); 348 349 if (test_bit(SCAN_HW_CANCELLED, &local->scanning)) 350 return false; 351 352 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 353 for (i = 0; i < req->n_channels; i++) { 354 local->hw_scan_req->req.channels[i] = req->channels[i]; 355 bands_used |= BIT(req->channels[i]->band); 356 } 357 358 n_chans = req->n_channels; 359 } else { 360 do { 361 if (local->hw_scan_band == NUM_NL80211_BANDS) 362 return false; 363 364 n_chans = 0; 365 366 for (i = 0; i < req->n_channels; i++) { 367 if (req->channels[i]->band != 368 local->hw_scan_band) 369 continue; 370 local->hw_scan_req->req.channels[n_chans] = 371 req->channels[i]; 372 n_chans++; 373 bands_used |= BIT(req->channels[i]->band); 374 } 375 376 local->hw_scan_band++; 377 } while (!n_chans); 378 } 379 380 local->hw_scan_req->req.n_channels = n_chans; 381 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 382 383 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 384 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 385 386 ielen = ieee80211_build_preq_ies(sdata, 387 (u8 *)local->hw_scan_req->req.ie, 388 local->hw_scan_ies_bufsize, 389 &local->hw_scan_req->ies, 390 req->ie, req->ie_len, 391 bands_used, req->rates, &chandef, 392 flags); 393 local->hw_scan_req->req.ie_len = ielen; 394 local->hw_scan_req->req.no_cck = req->no_cck; 395 ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr); 396 ether_addr_copy(local->hw_scan_req->req.mac_addr_mask, 397 req->mac_addr_mask); 398 ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid); 399 400 return true; 401 } 402 403 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) 404 { 405 struct ieee80211_local *local = hw_to_local(hw); 406 bool hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); 407 bool was_scanning = local->scanning; 408 struct cfg80211_scan_request *scan_req; 409 struct ieee80211_sub_if_data *scan_sdata; 410 struct ieee80211_sub_if_data *sdata; 411 412 lockdep_assert_held(&local->mtx); 413 414 /* 415 * It's ok to abort a not-yet-running scan (that 416 * we have one at all will be verified by checking 417 * local->scan_req next), but not to complete it 418 * successfully. 419 */ 420 if (WARN_ON(!local->scanning && !aborted)) 421 aborted = true; 422 423 if (WARN_ON(!local->scan_req)) 424 return; 425 426 scan_sdata = rcu_dereference_protected(local->scan_sdata, 427 lockdep_is_held(&local->mtx)); 428 429 if (hw_scan && !aborted && 430 !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) && 431 ieee80211_prep_hw_scan(scan_sdata)) { 432 int rc; 433 434 rc = drv_hw_scan(local, 435 rcu_dereference_protected(local->scan_sdata, 436 lockdep_is_held(&local->mtx)), 437 local->hw_scan_req); 438 439 if (rc == 0) 440 return; 441 442 /* HW scan failed and is going to be reported as aborted, 443 * so clear old scan info. 444 */ 445 memset(&local->scan_info, 0, sizeof(local->scan_info)); 446 aborted = true; 447 } 448 449 kfree(local->hw_scan_req); 450 local->hw_scan_req = NULL; 451 452 scan_req = rcu_dereference_protected(local->scan_req, 453 lockdep_is_held(&local->mtx)); 454 455 RCU_INIT_POINTER(local->scan_req, NULL); 456 RCU_INIT_POINTER(local->scan_sdata, NULL); 457 458 local->scanning = 0; 459 local->scan_chandef.chan = NULL; 460 461 synchronize_rcu(); 462 463 if (scan_req != local->int_scan_req) { 464 local->scan_info.aborted = aborted; 465 cfg80211_scan_done(scan_req, &local->scan_info); 466 } 467 468 /* Set power back to normal operating levels. */ 469 ieee80211_hw_config(local, 0); 470 471 if (!hw_scan && was_scanning) { 472 ieee80211_configure_filter(local); 473 drv_sw_scan_complete(local, scan_sdata); 474 ieee80211_offchannel_return(local); 475 } 476 477 ieee80211_recalc_idle(local); 478 479 ieee80211_mlme_notify_scan_completed(local); 480 ieee80211_ibss_notify_scan_completed(local); 481 482 /* Requeue all the work that might have been ignored while 483 * the scan was in progress; if there was none this will 484 * just be a no-op for the particular interface. 485 */ 486 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 487 if (ieee80211_sdata_running(sdata)) 488 wiphy_work_queue(sdata->local->hw.wiphy, &sdata->work); 489 } 490 491 if (was_scanning) 492 ieee80211_start_next_roc(local); 493 } 494 495 void ieee80211_scan_completed(struct ieee80211_hw *hw, 496 struct cfg80211_scan_info *info) 497 { 498 struct ieee80211_local *local = hw_to_local(hw); 499 500 trace_api_scan_completed(local, info->aborted); 501 502 set_bit(SCAN_COMPLETED, &local->scanning); 503 if (info->aborted) 504 set_bit(SCAN_ABORTED, &local->scanning); 505 506 memcpy(&local->scan_info, info, sizeof(*info)); 507 508 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0); 509 } 510 EXPORT_SYMBOL(ieee80211_scan_completed); 511 512 static int ieee80211_start_sw_scan(struct ieee80211_local *local, 513 struct ieee80211_sub_if_data *sdata) 514 { 515 /* Software scan is not supported in multi-channel cases */ 516 if (local->use_chanctx) 517 return -EOPNOTSUPP; 518 519 /* 520 * Hardware/driver doesn't support hw_scan, so use software 521 * scanning instead. First send a nullfunc frame with power save 522 * bit on so that AP will buffer the frames for us while we are not 523 * listening, then send probe requests to each channel and wait for 524 * the responses. After all channels are scanned, tune back to the 525 * original channel and send a nullfunc frame with power save bit 526 * off to trigger the AP to send us all the buffered frames. 527 * 528 * Note that while local->sw_scanning is true everything else but 529 * nullfunc frames and probe requests will be dropped in 530 * ieee80211_tx_h_check_assoc(). 531 */ 532 drv_sw_scan_start(local, sdata, local->scan_addr); 533 534 local->leave_oper_channel_time = jiffies; 535 local->next_scan_state = SCAN_DECISION; 536 local->scan_channel_idx = 0; 537 538 ieee80211_offchannel_stop_vifs(local); 539 540 /* ensure nullfunc is transmitted before leaving operating channel */ 541 ieee80211_flush_queues(local, NULL, false); 542 543 ieee80211_configure_filter(local); 544 545 /* We need to set power level at maximum rate for scanning. */ 546 ieee80211_hw_config(local, 0); 547 548 ieee80211_queue_delayed_work(&local->hw, 549 &local->scan_work, 0); 550 551 return 0; 552 } 553 554 static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata) 555 { 556 struct ieee80211_local *local = sdata->local; 557 struct ieee80211_sub_if_data *sdata_iter; 558 559 if (!ieee80211_is_radar_required(local)) 560 return true; 561 562 if (!regulatory_pre_cac_allowed(local->hw.wiphy)) 563 return false; 564 565 mutex_lock(&local->iflist_mtx); 566 list_for_each_entry(sdata_iter, &local->interfaces, list) { 567 if (sdata_iter->wdev.cac_started) { 568 mutex_unlock(&local->iflist_mtx); 569 return false; 570 } 571 } 572 mutex_unlock(&local->iflist_mtx); 573 574 return true; 575 } 576 577 static bool ieee80211_can_scan(struct ieee80211_local *local, 578 struct ieee80211_sub_if_data *sdata) 579 { 580 if (!__ieee80211_can_leave_ch(sdata)) 581 return false; 582 583 if (!list_empty(&local->roc_list)) 584 return false; 585 586 if (sdata->vif.type == NL80211_IFTYPE_STATION && 587 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL) 588 return false; 589 590 return true; 591 } 592 593 void ieee80211_run_deferred_scan(struct ieee80211_local *local) 594 { 595 lockdep_assert_held(&local->mtx); 596 597 if (!local->scan_req || local->scanning) 598 return; 599 600 if (!ieee80211_can_scan(local, 601 rcu_dereference_protected( 602 local->scan_sdata, 603 lockdep_is_held(&local->mtx)))) 604 return; 605 606 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 607 round_jiffies_relative(0)); 608 } 609 610 static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata, 611 const u8 *src, const u8 *dst, 612 const u8 *ssid, size_t ssid_len, 613 const u8 *ie, size_t ie_len, 614 u32 ratemask, u32 flags, u32 tx_flags, 615 struct ieee80211_channel *channel) 616 { 617 struct sk_buff *skb; 618 619 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel, 620 ssid, ssid_len, 621 ie, ie_len, flags); 622 623 if (skb) { 624 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) { 625 struct ieee80211_hdr *hdr = (void *)skb->data; 626 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 627 u16 sn = get_random_u16(); 628 629 info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO; 630 hdr->seq_ctrl = 631 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn)); 632 } 633 IEEE80211_SKB_CB(skb)->flags |= tx_flags; 634 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band); 635 } 636 } 637 638 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, 639 unsigned long *next_delay) 640 { 641 int i; 642 struct ieee80211_sub_if_data *sdata; 643 struct cfg80211_scan_request *scan_req; 644 enum nl80211_band band = local->hw.conf.chandef.chan->band; 645 u32 flags = 0, tx_flags; 646 647 scan_req = rcu_dereference_protected(local->scan_req, 648 lockdep_is_held(&local->mtx)); 649 650 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK; 651 if (scan_req->no_cck) 652 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE; 653 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 654 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 655 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN) 656 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN; 657 658 sdata = rcu_dereference_protected(local->scan_sdata, 659 lockdep_is_held(&local->mtx)); 660 661 for (i = 0; i < scan_req->n_ssids; i++) 662 ieee80211_send_scan_probe_req( 663 sdata, local->scan_addr, scan_req->bssid, 664 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len, 665 scan_req->ie, scan_req->ie_len, 666 scan_req->rates[band], flags, 667 tx_flags, local->hw.conf.chandef.chan); 668 669 /* 670 * After sending probe requests, wait for probe responses 671 * on the channel. 672 */ 673 *next_delay = IEEE80211_CHANNEL_TIME; 674 local->next_scan_state = SCAN_DECISION; 675 } 676 677 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, 678 struct cfg80211_scan_request *req) 679 { 680 struct ieee80211_local *local = sdata->local; 681 bool hw_scan = local->ops->hw_scan; 682 int rc; 683 684 lockdep_assert_held(&local->mtx); 685 686 if (local->scan_req) 687 return -EBUSY; 688 689 if (!__ieee80211_can_leave_ch(sdata)) 690 return -EBUSY; 691 692 if (!ieee80211_can_scan(local, sdata)) { 693 /* wait for the work to finish/time out */ 694 rcu_assign_pointer(local->scan_req, req); 695 rcu_assign_pointer(local->scan_sdata, sdata); 696 return 0; 697 } 698 699 again: 700 if (hw_scan) { 701 u8 *ies; 702 703 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len; 704 705 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 706 int i, n_bands = 0; 707 u8 bands_counted = 0; 708 709 for (i = 0; i < req->n_channels; i++) { 710 if (bands_counted & BIT(req->channels[i]->band)) 711 continue; 712 bands_counted |= BIT(req->channels[i]->band); 713 n_bands++; 714 } 715 716 local->hw_scan_ies_bufsize *= n_bands; 717 } 718 719 local->hw_scan_req = kmalloc( 720 sizeof(*local->hw_scan_req) + 721 req->n_channels * sizeof(req->channels[0]) + 722 local->hw_scan_ies_bufsize, GFP_KERNEL); 723 if (!local->hw_scan_req) 724 return -ENOMEM; 725 726 local->hw_scan_req->req.ssids = req->ssids; 727 local->hw_scan_req->req.n_ssids = req->n_ssids; 728 ies = (u8 *)local->hw_scan_req + 729 sizeof(*local->hw_scan_req) + 730 req->n_channels * sizeof(req->channels[0]); 731 local->hw_scan_req->req.ie = ies; 732 local->hw_scan_req->req.flags = req->flags; 733 eth_broadcast_addr(local->hw_scan_req->req.bssid); 734 local->hw_scan_req->req.duration = req->duration; 735 local->hw_scan_req->req.duration_mandatory = 736 req->duration_mandatory; 737 738 local->hw_scan_band = 0; 739 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params; 740 local->hw_scan_req->req.scan_6ghz_params = 741 req->scan_6ghz_params; 742 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz; 743 744 /* 745 * After allocating local->hw_scan_req, we must 746 * go through until ieee80211_prep_hw_scan(), so 747 * anything that might be changed here and leave 748 * this function early must not go after this 749 * allocation. 750 */ 751 } 752 753 rcu_assign_pointer(local->scan_req, req); 754 rcu_assign_pointer(local->scan_sdata, sdata); 755 756 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 757 get_random_mask_addr(local->scan_addr, 758 req->mac_addr, 759 req->mac_addr_mask); 760 else 761 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN); 762 763 if (hw_scan) { 764 __set_bit(SCAN_HW_SCANNING, &local->scanning); 765 } else if ((req->n_channels == 1) && 766 (req->channels[0] == local->_oper_chandef.chan)) { 767 /* 768 * If we are scanning only on the operating channel 769 * then we do not need to stop normal activities 770 */ 771 unsigned long next_delay; 772 773 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning); 774 775 ieee80211_recalc_idle(local); 776 777 /* Notify driver scan is starting, keep order of operations 778 * same as normal software scan, in case that matters. */ 779 drv_sw_scan_start(local, sdata, local->scan_addr); 780 781 ieee80211_configure_filter(local); /* accept probe-responses */ 782 783 /* We need to ensure power level is at max for scanning. */ 784 ieee80211_hw_config(local, 0); 785 786 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR | 787 IEEE80211_CHAN_RADAR)) || 788 !req->n_ssids) { 789 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 790 if (req->n_ssids) 791 set_bit(SCAN_BEACON_WAIT, &local->scanning); 792 } else { 793 ieee80211_scan_state_send_probe(local, &next_delay); 794 next_delay = IEEE80211_CHANNEL_TIME; 795 } 796 797 /* Now, just wait a bit and we are all done! */ 798 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 799 next_delay); 800 return 0; 801 } else { 802 /* Do normal software scan */ 803 __set_bit(SCAN_SW_SCANNING, &local->scanning); 804 } 805 806 ieee80211_recalc_idle(local); 807 808 if (hw_scan) { 809 WARN_ON(!ieee80211_prep_hw_scan(sdata)); 810 rc = drv_hw_scan(local, sdata, local->hw_scan_req); 811 } else { 812 rc = ieee80211_start_sw_scan(local, sdata); 813 } 814 815 if (rc) { 816 kfree(local->hw_scan_req); 817 local->hw_scan_req = NULL; 818 local->scanning = 0; 819 820 ieee80211_recalc_idle(local); 821 822 local->scan_req = NULL; 823 RCU_INIT_POINTER(local->scan_sdata, NULL); 824 } 825 826 if (hw_scan && rc == 1) { 827 /* 828 * we can't fall back to software for P2P-GO 829 * as it must update NoA etc. 830 */ 831 if (ieee80211_vif_type_p2p(&sdata->vif) == 832 NL80211_IFTYPE_P2P_GO) 833 return -EOPNOTSUPP; 834 hw_scan = false; 835 goto again; 836 } 837 838 return rc; 839 } 840 841 static unsigned long 842 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) 843 { 844 /* 845 * TODO: channel switching also consumes quite some time, 846 * add that delay as well to get a better estimation 847 */ 848 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) 849 return IEEE80211_PASSIVE_CHANNEL_TIME; 850 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; 851 } 852 853 static void ieee80211_scan_state_decision(struct ieee80211_local *local, 854 unsigned long *next_delay) 855 { 856 bool associated = false; 857 bool tx_empty = true; 858 bool bad_latency; 859 struct ieee80211_sub_if_data *sdata; 860 struct ieee80211_channel *next_chan; 861 enum mac80211_scan_state next_scan_state; 862 struct cfg80211_scan_request *scan_req; 863 864 /* 865 * check if at least one STA interface is associated, 866 * check if at least one STA interface has pending tx frames 867 * and grab the lowest used beacon interval 868 */ 869 mutex_lock(&local->iflist_mtx); 870 list_for_each_entry(sdata, &local->interfaces, list) { 871 if (!ieee80211_sdata_running(sdata)) 872 continue; 873 874 if (sdata->vif.type == NL80211_IFTYPE_STATION) { 875 if (sdata->u.mgd.associated) { 876 associated = true; 877 878 if (!qdisc_all_tx_empty(sdata->dev)) { 879 tx_empty = false; 880 break; 881 } 882 } 883 } 884 } 885 mutex_unlock(&local->iflist_mtx); 886 887 scan_req = rcu_dereference_protected(local->scan_req, 888 lockdep_is_held(&local->mtx)); 889 890 next_chan = scan_req->channels[local->scan_channel_idx]; 891 892 /* 893 * we're currently scanning a different channel, let's 894 * see if we can scan another channel without interfering 895 * with the current traffic situation. 896 * 897 * Keep good latency, do not stay off-channel more than 125 ms. 898 */ 899 900 bad_latency = time_after(jiffies + 901 ieee80211_scan_get_channel_time(next_chan), 902 local->leave_oper_channel_time + HZ / 8); 903 904 if (associated && !tx_empty) { 905 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY) 906 next_scan_state = SCAN_ABORT; 907 else 908 next_scan_state = SCAN_SUSPEND; 909 } else if (associated && bad_latency) { 910 next_scan_state = SCAN_SUSPEND; 911 } else { 912 next_scan_state = SCAN_SET_CHANNEL; 913 } 914 915 local->next_scan_state = next_scan_state; 916 917 *next_delay = 0; 918 } 919 920 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, 921 unsigned long *next_delay) 922 { 923 int skip; 924 struct ieee80211_channel *chan; 925 enum nl80211_bss_scan_width oper_scan_width; 926 struct cfg80211_scan_request *scan_req; 927 928 scan_req = rcu_dereference_protected(local->scan_req, 929 lockdep_is_held(&local->mtx)); 930 931 skip = 0; 932 chan = scan_req->channels[local->scan_channel_idx]; 933 934 local->scan_chandef.chan = chan; 935 local->scan_chandef.center_freq1 = chan->center_freq; 936 local->scan_chandef.freq1_offset = chan->freq_offset; 937 local->scan_chandef.center_freq2 = 0; 938 939 /* For scanning on the S1G band, ignore scan_width (which is constant 940 * across all channels) for now since channel width is specific to each 941 * channel. Detect the required channel width here and likely revisit 942 * later. Maybe scan_width could be used to build the channel scan list? 943 */ 944 if (chan->band == NL80211_BAND_S1GHZ) { 945 local->scan_chandef.width = ieee80211_s1g_channel_width(chan); 946 goto set_channel; 947 } 948 949 switch (scan_req->scan_width) { 950 case NL80211_BSS_CHAN_WIDTH_5: 951 local->scan_chandef.width = NL80211_CHAN_WIDTH_5; 952 break; 953 case NL80211_BSS_CHAN_WIDTH_10: 954 local->scan_chandef.width = NL80211_CHAN_WIDTH_10; 955 break; 956 default: 957 case NL80211_BSS_CHAN_WIDTH_20: 958 /* If scanning on oper channel, use whatever channel-type 959 * is currently in use. 960 */ 961 oper_scan_width = cfg80211_chandef_to_scan_width( 962 &local->_oper_chandef); 963 if (chan == local->_oper_chandef.chan && 964 oper_scan_width == scan_req->scan_width) 965 local->scan_chandef = local->_oper_chandef; 966 else 967 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT; 968 break; 969 case NL80211_BSS_CHAN_WIDTH_1: 970 case NL80211_BSS_CHAN_WIDTH_2: 971 /* shouldn't get here, S1G handled above */ 972 WARN_ON(1); 973 break; 974 } 975 976 set_channel: 977 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) 978 skip = 1; 979 980 /* advance state machine to next channel/band */ 981 local->scan_channel_idx++; 982 983 if (skip) { 984 /* if we skip this channel return to the decision state */ 985 local->next_scan_state = SCAN_DECISION; 986 return; 987 } 988 989 /* 990 * Probe delay is used to update the NAV, cf. 11.1.3.2.2 991 * (which unfortunately doesn't say _why_ step a) is done, 992 * but it waits for the probe delay or until a frame is 993 * received - and the received frame would update the NAV). 994 * For now, we do not support waiting until a frame is 995 * received. 996 * 997 * In any case, it is not necessary for a passive scan. 998 */ 999 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) || 1000 !scan_req->n_ssids) { 1001 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 1002 local->next_scan_state = SCAN_DECISION; 1003 if (scan_req->n_ssids) 1004 set_bit(SCAN_BEACON_WAIT, &local->scanning); 1005 return; 1006 } 1007 1008 /* active scan, send probes */ 1009 *next_delay = IEEE80211_PROBE_DELAY; 1010 local->next_scan_state = SCAN_SEND_PROBE; 1011 } 1012 1013 static void ieee80211_scan_state_suspend(struct ieee80211_local *local, 1014 unsigned long *next_delay) 1015 { 1016 /* switch back to the operating channel */ 1017 local->scan_chandef.chan = NULL; 1018 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 1019 1020 /* disable PS */ 1021 ieee80211_offchannel_return(local); 1022 1023 *next_delay = HZ / 5; 1024 /* afterwards, resume scan & go to next channel */ 1025 local->next_scan_state = SCAN_RESUME; 1026 } 1027 1028 static void ieee80211_scan_state_resume(struct ieee80211_local *local, 1029 unsigned long *next_delay) 1030 { 1031 ieee80211_offchannel_stop_vifs(local); 1032 1033 if (local->ops->flush) { 1034 ieee80211_flush_queues(local, NULL, false); 1035 *next_delay = 0; 1036 } else 1037 *next_delay = HZ / 10; 1038 1039 /* remember when we left the operating channel */ 1040 local->leave_oper_channel_time = jiffies; 1041 1042 /* advance to the next channel to be scanned */ 1043 local->next_scan_state = SCAN_SET_CHANNEL; 1044 } 1045 1046 void ieee80211_scan_work(struct work_struct *work) 1047 { 1048 struct ieee80211_local *local = 1049 container_of(work, struct ieee80211_local, scan_work.work); 1050 struct ieee80211_sub_if_data *sdata; 1051 struct cfg80211_scan_request *scan_req; 1052 unsigned long next_delay = 0; 1053 bool aborted; 1054 1055 mutex_lock(&local->mtx); 1056 1057 if (!ieee80211_can_run_worker(local)) { 1058 aborted = true; 1059 goto out_complete; 1060 } 1061 1062 sdata = rcu_dereference_protected(local->scan_sdata, 1063 lockdep_is_held(&local->mtx)); 1064 scan_req = rcu_dereference_protected(local->scan_req, 1065 lockdep_is_held(&local->mtx)); 1066 1067 /* When scanning on-channel, the first-callback means completed. */ 1068 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) { 1069 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1070 goto out_complete; 1071 } 1072 1073 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) { 1074 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1075 goto out_complete; 1076 } 1077 1078 if (!sdata || !scan_req) 1079 goto out; 1080 1081 if (!local->scanning) { 1082 int rc; 1083 1084 RCU_INIT_POINTER(local->scan_req, NULL); 1085 RCU_INIT_POINTER(local->scan_sdata, NULL); 1086 1087 rc = __ieee80211_start_scan(sdata, scan_req); 1088 if (rc) { 1089 /* need to complete scan in cfg80211 */ 1090 rcu_assign_pointer(local->scan_req, scan_req); 1091 aborted = true; 1092 goto out_complete; 1093 } else 1094 goto out; 1095 } 1096 1097 clear_bit(SCAN_BEACON_WAIT, &local->scanning); 1098 1099 /* 1100 * as long as no delay is required advance immediately 1101 * without scheduling a new work 1102 */ 1103 do { 1104 if (!ieee80211_sdata_running(sdata)) { 1105 aborted = true; 1106 goto out_complete; 1107 } 1108 1109 if (test_and_clear_bit(SCAN_BEACON_DONE, &local->scanning) && 1110 local->next_scan_state == SCAN_DECISION) 1111 local->next_scan_state = SCAN_SEND_PROBE; 1112 1113 switch (local->next_scan_state) { 1114 case SCAN_DECISION: 1115 /* if no more bands/channels left, complete scan */ 1116 if (local->scan_channel_idx >= scan_req->n_channels) { 1117 aborted = false; 1118 goto out_complete; 1119 } 1120 ieee80211_scan_state_decision(local, &next_delay); 1121 break; 1122 case SCAN_SET_CHANNEL: 1123 ieee80211_scan_state_set_channel(local, &next_delay); 1124 break; 1125 case SCAN_SEND_PROBE: 1126 ieee80211_scan_state_send_probe(local, &next_delay); 1127 break; 1128 case SCAN_SUSPEND: 1129 ieee80211_scan_state_suspend(local, &next_delay); 1130 break; 1131 case SCAN_RESUME: 1132 ieee80211_scan_state_resume(local, &next_delay); 1133 break; 1134 case SCAN_ABORT: 1135 aborted = true; 1136 goto out_complete; 1137 } 1138 } while (next_delay == 0); 1139 1140 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay); 1141 goto out; 1142 1143 out_complete: 1144 __ieee80211_scan_completed(&local->hw, aborted); 1145 out: 1146 mutex_unlock(&local->mtx); 1147 } 1148 1149 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, 1150 struct cfg80211_scan_request *req) 1151 { 1152 int res; 1153 1154 mutex_lock(&sdata->local->mtx); 1155 res = __ieee80211_start_scan(sdata, req); 1156 mutex_unlock(&sdata->local->mtx); 1157 1158 return res; 1159 } 1160 1161 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata, 1162 const u8 *ssid, u8 ssid_len, 1163 struct ieee80211_channel **channels, 1164 unsigned int n_channels, 1165 enum nl80211_bss_scan_width scan_width) 1166 { 1167 struct ieee80211_local *local = sdata->local; 1168 int ret = -EBUSY, i, n_ch = 0; 1169 enum nl80211_band band; 1170 1171 mutex_lock(&local->mtx); 1172 1173 /* busy scanning */ 1174 if (local->scan_req) 1175 goto unlock; 1176 1177 /* fill internal scan request */ 1178 if (!channels) { 1179 int max_n; 1180 1181 for (band = 0; band < NUM_NL80211_BANDS; band++) { 1182 if (!local->hw.wiphy->bands[band] || 1183 band == NL80211_BAND_6GHZ) 1184 continue; 1185 1186 max_n = local->hw.wiphy->bands[band]->n_channels; 1187 for (i = 0; i < max_n; i++) { 1188 struct ieee80211_channel *tmp_ch = 1189 &local->hw.wiphy->bands[band]->channels[i]; 1190 1191 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR | 1192 IEEE80211_CHAN_DISABLED)) 1193 continue; 1194 1195 local->int_scan_req->channels[n_ch] = tmp_ch; 1196 n_ch++; 1197 } 1198 } 1199 1200 if (WARN_ON_ONCE(n_ch == 0)) 1201 goto unlock; 1202 1203 local->int_scan_req->n_channels = n_ch; 1204 } else { 1205 for (i = 0; i < n_channels; i++) { 1206 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR | 1207 IEEE80211_CHAN_DISABLED)) 1208 continue; 1209 1210 local->int_scan_req->channels[n_ch] = channels[i]; 1211 n_ch++; 1212 } 1213 1214 if (WARN_ON_ONCE(n_ch == 0)) 1215 goto unlock; 1216 1217 local->int_scan_req->n_channels = n_ch; 1218 } 1219 1220 local->int_scan_req->ssids = &local->scan_ssid; 1221 local->int_scan_req->n_ssids = 1; 1222 local->int_scan_req->scan_width = scan_width; 1223 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); 1224 local->int_scan_req->ssids[0].ssid_len = ssid_len; 1225 1226 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); 1227 unlock: 1228 mutex_unlock(&local->mtx); 1229 return ret; 1230 } 1231 1232 void ieee80211_scan_cancel(struct ieee80211_local *local) 1233 { 1234 /* ensure a new scan cannot be queued */ 1235 lockdep_assert_wiphy(local->hw.wiphy); 1236 1237 /* 1238 * We are canceling software scan, or deferred scan that was not 1239 * yet really started (see __ieee80211_start_scan ). 1240 * 1241 * Regarding hardware scan: 1242 * - we can not call __ieee80211_scan_completed() as when 1243 * SCAN_HW_SCANNING bit is set this function change 1244 * local->hw_scan_req to operate on 5G band, what race with 1245 * driver which can use local->hw_scan_req 1246 * 1247 * - we can not cancel scan_work since driver can schedule it 1248 * by ieee80211_scan_completed(..., true) to finish scan 1249 * 1250 * Hence we only call the cancel_hw_scan() callback, but the low-level 1251 * driver is still responsible for calling ieee80211_scan_completed() 1252 * after the scan was completed/aborted. 1253 */ 1254 1255 mutex_lock(&local->mtx); 1256 if (!local->scan_req) 1257 goto out; 1258 1259 /* 1260 * We have a scan running and the driver already reported completion, 1261 * but the worker hasn't run yet or is stuck on the mutex - mark it as 1262 * cancelled. 1263 */ 1264 if (test_bit(SCAN_HW_SCANNING, &local->scanning) && 1265 test_bit(SCAN_COMPLETED, &local->scanning)) { 1266 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1267 goto out; 1268 } 1269 1270 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) { 1271 /* 1272 * Make sure that __ieee80211_scan_completed doesn't trigger a 1273 * scan on another band. 1274 */ 1275 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1276 if (local->ops->cancel_hw_scan) 1277 drv_cancel_hw_scan(local, 1278 rcu_dereference_protected(local->scan_sdata, 1279 lockdep_is_held(&local->mtx))); 1280 goto out; 1281 } 1282 1283 /* 1284 * If the work is currently running, it must be blocked on 1285 * the mutex, but we'll set scan_sdata = NULL and it'll 1286 * simply exit once it acquires the mutex. 1287 */ 1288 cancel_delayed_work(&local->scan_work); 1289 /* and clean up */ 1290 memset(&local->scan_info, 0, sizeof(local->scan_info)); 1291 __ieee80211_scan_completed(&local->hw, true); 1292 out: 1293 mutex_unlock(&local->mtx); 1294 } 1295 1296 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1297 struct cfg80211_sched_scan_request *req) 1298 { 1299 struct ieee80211_local *local = sdata->local; 1300 struct ieee80211_scan_ies sched_scan_ies = {}; 1301 struct cfg80211_chan_def chandef; 1302 int ret, i, iebufsz, num_bands = 0; 1303 u32 rate_masks[NUM_NL80211_BANDS] = {}; 1304 u8 bands_used = 0; 1305 u8 *ie; 1306 u32 flags = 0; 1307 1308 iebufsz = local->scan_ies_len + req->ie_len; 1309 1310 lockdep_assert_held(&local->mtx); 1311 1312 if (!local->ops->sched_scan_start) 1313 return -ENOTSUPP; 1314 1315 for (i = 0; i < NUM_NL80211_BANDS; i++) { 1316 if (local->hw.wiphy->bands[i]) { 1317 bands_used |= BIT(i); 1318 rate_masks[i] = (u32) -1; 1319 num_bands++; 1320 } 1321 } 1322 1323 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 1324 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 1325 1326 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL); 1327 if (!ie) { 1328 ret = -ENOMEM; 1329 goto out; 1330 } 1331 1332 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 1333 1334 ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz, 1335 &sched_scan_ies, req->ie, 1336 req->ie_len, bands_used, rate_masks, &chandef, 1337 flags); 1338 1339 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies); 1340 if (ret == 0) { 1341 rcu_assign_pointer(local->sched_scan_sdata, sdata); 1342 rcu_assign_pointer(local->sched_scan_req, req); 1343 } 1344 1345 kfree(ie); 1346 1347 out: 1348 if (ret) { 1349 /* Clean in case of failure after HW restart or upon resume. */ 1350 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1351 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1352 } 1353 1354 return ret; 1355 } 1356 1357 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1358 struct cfg80211_sched_scan_request *req) 1359 { 1360 struct ieee80211_local *local = sdata->local; 1361 int ret; 1362 1363 mutex_lock(&local->mtx); 1364 1365 if (rcu_access_pointer(local->sched_scan_sdata)) { 1366 mutex_unlock(&local->mtx); 1367 return -EBUSY; 1368 } 1369 1370 ret = __ieee80211_request_sched_scan_start(sdata, req); 1371 1372 mutex_unlock(&local->mtx); 1373 return ret; 1374 } 1375 1376 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local) 1377 { 1378 struct ieee80211_sub_if_data *sched_scan_sdata; 1379 int ret = -ENOENT; 1380 1381 mutex_lock(&local->mtx); 1382 1383 if (!local->ops->sched_scan_stop) { 1384 ret = -ENOTSUPP; 1385 goto out; 1386 } 1387 1388 /* We don't want to restart sched scan anymore. */ 1389 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1390 1391 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata, 1392 lockdep_is_held(&local->mtx)); 1393 if (sched_scan_sdata) { 1394 ret = drv_sched_scan_stop(local, sched_scan_sdata); 1395 if (!ret) 1396 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1397 } 1398 out: 1399 mutex_unlock(&local->mtx); 1400 1401 return ret; 1402 } 1403 1404 void ieee80211_sched_scan_results(struct ieee80211_hw *hw) 1405 { 1406 struct ieee80211_local *local = hw_to_local(hw); 1407 1408 trace_api_sched_scan_results(local); 1409 1410 cfg80211_sched_scan_results(hw->wiphy, 0); 1411 } 1412 EXPORT_SYMBOL(ieee80211_sched_scan_results); 1413 1414 void ieee80211_sched_scan_end(struct ieee80211_local *local) 1415 { 1416 mutex_lock(&local->mtx); 1417 1418 if (!rcu_access_pointer(local->sched_scan_sdata)) { 1419 mutex_unlock(&local->mtx); 1420 return; 1421 } 1422 1423 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1424 1425 /* If sched scan was aborted by the driver. */ 1426 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1427 1428 mutex_unlock(&local->mtx); 1429 1430 cfg80211_sched_scan_stopped(local->hw.wiphy, 0); 1431 } 1432 1433 void ieee80211_sched_scan_stopped_work(struct work_struct *work) 1434 { 1435 struct ieee80211_local *local = 1436 container_of(work, struct ieee80211_local, 1437 sched_scan_stopped_work); 1438 1439 ieee80211_sched_scan_end(local); 1440 } 1441 1442 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw) 1443 { 1444 struct ieee80211_local *local = hw_to_local(hw); 1445 1446 trace_api_sched_scan_stopped(local); 1447 1448 /* 1449 * this shouldn't really happen, so for simplicity 1450 * simply ignore it, and let mac80211 reconfigure 1451 * the sched scan later on. 1452 */ 1453 if (local->in_reconfig) 1454 return; 1455 1456 schedule_work(&local->sched_scan_stopped_work); 1457 } 1458 EXPORT_SYMBOL(ieee80211_sched_scan_stopped); 1459