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( 726 sizeof(*local->hw_scan_req) + 727 req->n_channels * sizeof(req->channels[0]) + 728 local->hw_scan_ies_bufsize, GFP_KERNEL); 729 if (!local->hw_scan_req) 730 return -ENOMEM; 731 732 local->hw_scan_req->req.ssids = req->ssids; 733 local->hw_scan_req->req.n_ssids = req->n_ssids; 734 ies = (u8 *)local->hw_scan_req + 735 sizeof(*local->hw_scan_req) + 736 req->n_channels * sizeof(req->channels[0]); 737 local->hw_scan_req->req.ie = ies; 738 local->hw_scan_req->req.flags = req->flags; 739 eth_broadcast_addr(local->hw_scan_req->req.bssid); 740 local->hw_scan_req->req.duration = req->duration; 741 local->hw_scan_req->req.duration_mandatory = 742 req->duration_mandatory; 743 744 local->hw_scan_band = 0; 745 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params; 746 local->hw_scan_req->req.scan_6ghz_params = 747 req->scan_6ghz_params; 748 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz; 749 750 /* 751 * After allocating local->hw_scan_req, we must 752 * go through until ieee80211_prep_hw_scan(), so 753 * anything that might be changed here and leave 754 * this function early must not go after this 755 * allocation. 756 */ 757 } 758 759 rcu_assign_pointer(local->scan_req, req); 760 rcu_assign_pointer(local->scan_sdata, sdata); 761 762 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 763 get_random_mask_addr(local->scan_addr, 764 req->mac_addr, 765 req->mac_addr_mask); 766 else 767 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN); 768 769 if (hw_scan) { 770 __set_bit(SCAN_HW_SCANNING, &local->scanning); 771 } else if ((req->n_channels == 1) && 772 (req->channels[0] == local->_oper_chandef.chan)) { 773 /* 774 * If we are scanning only on the operating channel 775 * then we do not need to stop normal activities 776 */ 777 unsigned long next_delay; 778 779 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning); 780 781 ieee80211_recalc_idle(local); 782 783 /* Notify driver scan is starting, keep order of operations 784 * same as normal software scan, in case that matters. */ 785 drv_sw_scan_start(local, sdata, local->scan_addr); 786 787 ieee80211_configure_filter(local); /* accept probe-responses */ 788 789 /* We need to ensure power level is at max for scanning. */ 790 ieee80211_hw_config(local, 0); 791 792 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR | 793 IEEE80211_CHAN_RADAR)) || 794 !req->n_ssids) { 795 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 796 if (req->n_ssids) 797 set_bit(SCAN_BEACON_WAIT, &local->scanning); 798 } else { 799 ieee80211_scan_state_send_probe(local, &next_delay); 800 next_delay = IEEE80211_CHANNEL_TIME; 801 } 802 803 /* Now, just wait a bit and we are all done! */ 804 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 805 next_delay); 806 return 0; 807 } else { 808 /* Do normal software scan */ 809 __set_bit(SCAN_SW_SCANNING, &local->scanning); 810 } 811 812 ieee80211_recalc_idle(local); 813 814 if (hw_scan) { 815 WARN_ON(!ieee80211_prep_hw_scan(sdata)); 816 rc = drv_hw_scan(local, sdata, local->hw_scan_req); 817 } else { 818 rc = ieee80211_start_sw_scan(local, sdata); 819 } 820 821 if (rc) { 822 kfree(local->hw_scan_req); 823 local->hw_scan_req = NULL; 824 local->scanning = 0; 825 826 ieee80211_recalc_idle(local); 827 828 local->scan_req = NULL; 829 RCU_INIT_POINTER(local->scan_sdata, NULL); 830 } 831 832 if (hw_scan && rc == 1) { 833 /* 834 * we can't fall back to software for P2P-GO 835 * as it must update NoA etc. 836 */ 837 if (ieee80211_vif_type_p2p(&sdata->vif) == 838 NL80211_IFTYPE_P2P_GO) 839 return -EOPNOTSUPP; 840 hw_scan = false; 841 goto again; 842 } 843 844 return rc; 845 } 846 847 static unsigned long 848 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) 849 { 850 /* 851 * TODO: channel switching also consumes quite some time, 852 * add that delay as well to get a better estimation 853 */ 854 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) 855 return IEEE80211_PASSIVE_CHANNEL_TIME; 856 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; 857 } 858 859 static void ieee80211_scan_state_decision(struct ieee80211_local *local, 860 unsigned long *next_delay) 861 { 862 bool associated = false; 863 bool tx_empty = true; 864 bool bad_latency; 865 struct ieee80211_sub_if_data *sdata; 866 struct ieee80211_channel *next_chan; 867 enum mac80211_scan_state next_scan_state; 868 struct cfg80211_scan_request *scan_req; 869 870 /* 871 * check if at least one STA interface is associated, 872 * check if at least one STA interface has pending tx frames 873 * and grab the lowest used beacon interval 874 */ 875 mutex_lock(&local->iflist_mtx); 876 list_for_each_entry(sdata, &local->interfaces, list) { 877 if (!ieee80211_sdata_running(sdata)) 878 continue; 879 880 if (sdata->vif.type == NL80211_IFTYPE_STATION) { 881 if (sdata->u.mgd.associated) { 882 associated = true; 883 884 if (!qdisc_all_tx_empty(sdata->dev)) { 885 tx_empty = false; 886 break; 887 } 888 } 889 } 890 } 891 mutex_unlock(&local->iflist_mtx); 892 893 scan_req = rcu_dereference_protected(local->scan_req, 894 lockdep_is_held(&local->mtx)); 895 896 next_chan = scan_req->channels[local->scan_channel_idx]; 897 898 /* 899 * we're currently scanning a different channel, let's 900 * see if we can scan another channel without interfering 901 * with the current traffic situation. 902 * 903 * Keep good latency, do not stay off-channel more than 125 ms. 904 */ 905 906 bad_latency = time_after(jiffies + 907 ieee80211_scan_get_channel_time(next_chan), 908 local->leave_oper_channel_time + HZ / 8); 909 910 if (associated && !tx_empty) { 911 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY) 912 next_scan_state = SCAN_ABORT; 913 else 914 next_scan_state = SCAN_SUSPEND; 915 } else if (associated && bad_latency) { 916 next_scan_state = SCAN_SUSPEND; 917 } else { 918 next_scan_state = SCAN_SET_CHANNEL; 919 } 920 921 local->next_scan_state = next_scan_state; 922 923 *next_delay = 0; 924 } 925 926 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, 927 unsigned long *next_delay) 928 { 929 int skip; 930 struct ieee80211_channel *chan; 931 enum nl80211_bss_scan_width oper_scan_width; 932 struct cfg80211_scan_request *scan_req; 933 934 scan_req = rcu_dereference_protected(local->scan_req, 935 lockdep_is_held(&local->mtx)); 936 937 skip = 0; 938 chan = scan_req->channels[local->scan_channel_idx]; 939 940 local->scan_chandef.chan = chan; 941 local->scan_chandef.center_freq1 = chan->center_freq; 942 local->scan_chandef.freq1_offset = chan->freq_offset; 943 local->scan_chandef.center_freq2 = 0; 944 945 /* For scanning on the S1G band, ignore scan_width (which is constant 946 * across all channels) for now since channel width is specific to each 947 * channel. Detect the required channel width here and likely revisit 948 * later. Maybe scan_width could be used to build the channel scan list? 949 */ 950 if (chan->band == NL80211_BAND_S1GHZ) { 951 local->scan_chandef.width = ieee80211_s1g_channel_width(chan); 952 goto set_channel; 953 } 954 955 switch (scan_req->scan_width) { 956 case NL80211_BSS_CHAN_WIDTH_5: 957 local->scan_chandef.width = NL80211_CHAN_WIDTH_5; 958 break; 959 case NL80211_BSS_CHAN_WIDTH_10: 960 local->scan_chandef.width = NL80211_CHAN_WIDTH_10; 961 break; 962 default: 963 case NL80211_BSS_CHAN_WIDTH_20: 964 /* If scanning on oper channel, use whatever channel-type 965 * is currently in use. 966 */ 967 oper_scan_width = cfg80211_chandef_to_scan_width( 968 &local->_oper_chandef); 969 if (chan == local->_oper_chandef.chan && 970 oper_scan_width == scan_req->scan_width) 971 local->scan_chandef = local->_oper_chandef; 972 else 973 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT; 974 break; 975 case NL80211_BSS_CHAN_WIDTH_1: 976 case NL80211_BSS_CHAN_WIDTH_2: 977 /* shouldn't get here, S1G handled above */ 978 WARN_ON(1); 979 break; 980 } 981 982 set_channel: 983 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) 984 skip = 1; 985 986 /* advance state machine to next channel/band */ 987 local->scan_channel_idx++; 988 989 if (skip) { 990 /* if we skip this channel return to the decision state */ 991 local->next_scan_state = SCAN_DECISION; 992 return; 993 } 994 995 /* 996 * Probe delay is used to update the NAV, cf. 11.1.3.2.2 997 * (which unfortunately doesn't say _why_ step a) is done, 998 * but it waits for the probe delay or until a frame is 999 * received - and the received frame would update the NAV). 1000 * For now, we do not support waiting until a frame is 1001 * received. 1002 * 1003 * In any case, it is not necessary for a passive scan. 1004 */ 1005 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) || 1006 !scan_req->n_ssids) { 1007 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 1008 local->next_scan_state = SCAN_DECISION; 1009 if (scan_req->n_ssids) 1010 set_bit(SCAN_BEACON_WAIT, &local->scanning); 1011 return; 1012 } 1013 1014 /* active scan, send probes */ 1015 *next_delay = IEEE80211_PROBE_DELAY; 1016 local->next_scan_state = SCAN_SEND_PROBE; 1017 } 1018 1019 static void ieee80211_scan_state_suspend(struct ieee80211_local *local, 1020 unsigned long *next_delay) 1021 { 1022 /* switch back to the operating channel */ 1023 local->scan_chandef.chan = NULL; 1024 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 1025 1026 /* disable PS */ 1027 ieee80211_offchannel_return(local); 1028 1029 *next_delay = HZ / 5; 1030 /* afterwards, resume scan & go to next channel */ 1031 local->next_scan_state = SCAN_RESUME; 1032 } 1033 1034 static void ieee80211_scan_state_resume(struct ieee80211_local *local, 1035 unsigned long *next_delay) 1036 { 1037 ieee80211_offchannel_stop_vifs(local); 1038 1039 if (local->ops->flush) { 1040 ieee80211_flush_queues(local, NULL, false); 1041 *next_delay = 0; 1042 } else 1043 *next_delay = HZ / 10; 1044 1045 /* remember when we left the operating channel */ 1046 local->leave_oper_channel_time = jiffies; 1047 1048 /* advance to the next channel to be scanned */ 1049 local->next_scan_state = SCAN_SET_CHANNEL; 1050 } 1051 1052 void ieee80211_scan_work(struct wiphy *wiphy, struct wiphy_work *work) 1053 { 1054 struct ieee80211_local *local = 1055 container_of(work, struct ieee80211_local, scan_work.work); 1056 struct ieee80211_sub_if_data *sdata; 1057 struct cfg80211_scan_request *scan_req; 1058 unsigned long next_delay = 0; 1059 bool aborted; 1060 1061 mutex_lock(&local->mtx); 1062 1063 if (!ieee80211_can_run_worker(local)) { 1064 aborted = true; 1065 goto out_complete; 1066 } 1067 1068 sdata = rcu_dereference_protected(local->scan_sdata, 1069 lockdep_is_held(&local->mtx)); 1070 scan_req = rcu_dereference_protected(local->scan_req, 1071 lockdep_is_held(&local->mtx)); 1072 1073 /* When scanning on-channel, the first-callback means completed. */ 1074 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) { 1075 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1076 goto out_complete; 1077 } 1078 1079 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) { 1080 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1081 goto out_complete; 1082 } 1083 1084 if (!sdata || !scan_req) 1085 goto out; 1086 1087 if (!local->scanning) { 1088 int rc; 1089 1090 RCU_INIT_POINTER(local->scan_req, NULL); 1091 RCU_INIT_POINTER(local->scan_sdata, NULL); 1092 1093 rc = __ieee80211_start_scan(sdata, scan_req); 1094 if (rc) { 1095 /* need to complete scan in cfg80211 */ 1096 rcu_assign_pointer(local->scan_req, scan_req); 1097 aborted = true; 1098 goto out_complete; 1099 } else 1100 goto out; 1101 } 1102 1103 clear_bit(SCAN_BEACON_WAIT, &local->scanning); 1104 1105 /* 1106 * as long as no delay is required advance immediately 1107 * without scheduling a new work 1108 */ 1109 do { 1110 if (!ieee80211_sdata_running(sdata)) { 1111 aborted = true; 1112 goto out_complete; 1113 } 1114 1115 if (test_and_clear_bit(SCAN_BEACON_DONE, &local->scanning) && 1116 local->next_scan_state == SCAN_DECISION) 1117 local->next_scan_state = SCAN_SEND_PROBE; 1118 1119 switch (local->next_scan_state) { 1120 case SCAN_DECISION: 1121 /* if no more bands/channels left, complete scan */ 1122 if (local->scan_channel_idx >= scan_req->n_channels) { 1123 aborted = false; 1124 goto out_complete; 1125 } 1126 ieee80211_scan_state_decision(local, &next_delay); 1127 break; 1128 case SCAN_SET_CHANNEL: 1129 ieee80211_scan_state_set_channel(local, &next_delay); 1130 break; 1131 case SCAN_SEND_PROBE: 1132 ieee80211_scan_state_send_probe(local, &next_delay); 1133 break; 1134 case SCAN_SUSPEND: 1135 ieee80211_scan_state_suspend(local, &next_delay); 1136 break; 1137 case SCAN_RESUME: 1138 ieee80211_scan_state_resume(local, &next_delay); 1139 break; 1140 case SCAN_ABORT: 1141 aborted = true; 1142 goto out_complete; 1143 } 1144 } while (next_delay == 0); 1145 1146 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 1147 next_delay); 1148 goto out; 1149 1150 out_complete: 1151 __ieee80211_scan_completed(&local->hw, aborted); 1152 out: 1153 mutex_unlock(&local->mtx); 1154 } 1155 1156 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, 1157 struct cfg80211_scan_request *req) 1158 { 1159 int res; 1160 1161 mutex_lock(&sdata->local->mtx); 1162 res = __ieee80211_start_scan(sdata, req); 1163 mutex_unlock(&sdata->local->mtx); 1164 1165 return res; 1166 } 1167 1168 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata, 1169 const u8 *ssid, u8 ssid_len, 1170 struct ieee80211_channel **channels, 1171 unsigned int n_channels, 1172 enum nl80211_bss_scan_width scan_width) 1173 { 1174 struct ieee80211_local *local = sdata->local; 1175 int ret = -EBUSY, i, n_ch = 0; 1176 enum nl80211_band band; 1177 1178 mutex_lock(&local->mtx); 1179 1180 /* busy scanning */ 1181 if (local->scan_req) 1182 goto unlock; 1183 1184 /* fill internal scan request */ 1185 if (!channels) { 1186 int max_n; 1187 1188 for (band = 0; band < NUM_NL80211_BANDS; band++) { 1189 if (!local->hw.wiphy->bands[band] || 1190 band == NL80211_BAND_6GHZ) 1191 continue; 1192 1193 max_n = local->hw.wiphy->bands[band]->n_channels; 1194 for (i = 0; i < max_n; i++) { 1195 struct ieee80211_channel *tmp_ch = 1196 &local->hw.wiphy->bands[band]->channels[i]; 1197 1198 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR | 1199 IEEE80211_CHAN_DISABLED)) 1200 continue; 1201 1202 local->int_scan_req->channels[n_ch] = tmp_ch; 1203 n_ch++; 1204 } 1205 } 1206 1207 if (WARN_ON_ONCE(n_ch == 0)) 1208 goto unlock; 1209 1210 local->int_scan_req->n_channels = n_ch; 1211 } else { 1212 for (i = 0; i < n_channels; i++) { 1213 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR | 1214 IEEE80211_CHAN_DISABLED)) 1215 continue; 1216 1217 local->int_scan_req->channels[n_ch] = channels[i]; 1218 n_ch++; 1219 } 1220 1221 if (WARN_ON_ONCE(n_ch == 0)) 1222 goto unlock; 1223 1224 local->int_scan_req->n_channels = n_ch; 1225 } 1226 1227 local->int_scan_req->ssids = &local->scan_ssid; 1228 local->int_scan_req->n_ssids = 1; 1229 local->int_scan_req->scan_width = scan_width; 1230 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); 1231 local->int_scan_req->ssids[0].ssid_len = ssid_len; 1232 1233 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); 1234 unlock: 1235 mutex_unlock(&local->mtx); 1236 return ret; 1237 } 1238 1239 void ieee80211_scan_cancel(struct ieee80211_local *local) 1240 { 1241 /* ensure a new scan cannot be queued */ 1242 lockdep_assert_wiphy(local->hw.wiphy); 1243 1244 /* 1245 * We are canceling software scan, or deferred scan that was not 1246 * yet really started (see __ieee80211_start_scan ). 1247 * 1248 * Regarding hardware scan: 1249 * - we can not call __ieee80211_scan_completed() as when 1250 * SCAN_HW_SCANNING bit is set this function change 1251 * local->hw_scan_req to operate on 5G band, what race with 1252 * driver which can use local->hw_scan_req 1253 * 1254 * - we can not cancel scan_work since driver can schedule it 1255 * by ieee80211_scan_completed(..., true) to finish scan 1256 * 1257 * Hence we only call the cancel_hw_scan() callback, but the low-level 1258 * driver is still responsible for calling ieee80211_scan_completed() 1259 * after the scan was completed/aborted. 1260 */ 1261 1262 mutex_lock(&local->mtx); 1263 if (!local->scan_req) 1264 goto out; 1265 1266 /* 1267 * We have a scan running and the driver already reported completion, 1268 * but the worker hasn't run yet or is stuck on the mutex - mark it as 1269 * cancelled. 1270 */ 1271 if (test_bit(SCAN_HW_SCANNING, &local->scanning) && 1272 test_bit(SCAN_COMPLETED, &local->scanning)) { 1273 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1274 goto out; 1275 } 1276 1277 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) { 1278 /* 1279 * Make sure that __ieee80211_scan_completed doesn't trigger a 1280 * scan on another band. 1281 */ 1282 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1283 if (local->ops->cancel_hw_scan) 1284 drv_cancel_hw_scan(local, 1285 rcu_dereference_protected(local->scan_sdata, 1286 lockdep_is_held(&local->mtx))); 1287 goto out; 1288 } 1289 1290 wiphy_delayed_work_cancel(local->hw.wiphy, &local->scan_work); 1291 /* and clean up */ 1292 memset(&local->scan_info, 0, sizeof(local->scan_info)); 1293 __ieee80211_scan_completed(&local->hw, true); 1294 out: 1295 mutex_unlock(&local->mtx); 1296 } 1297 1298 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1299 struct cfg80211_sched_scan_request *req) 1300 { 1301 struct ieee80211_local *local = sdata->local; 1302 struct ieee80211_scan_ies sched_scan_ies = {}; 1303 struct cfg80211_chan_def chandef; 1304 int ret, i, iebufsz, num_bands = 0; 1305 u32 rate_masks[NUM_NL80211_BANDS] = {}; 1306 u8 bands_used = 0; 1307 u8 *ie; 1308 u32 flags = 0; 1309 1310 iebufsz = local->scan_ies_len + req->ie_len; 1311 1312 lockdep_assert_held(&local->mtx); 1313 1314 if (!local->ops->sched_scan_start) 1315 return -ENOTSUPP; 1316 1317 for (i = 0; i < NUM_NL80211_BANDS; i++) { 1318 if (local->hw.wiphy->bands[i]) { 1319 bands_used |= BIT(i); 1320 rate_masks[i] = (u32) -1; 1321 num_bands++; 1322 } 1323 } 1324 1325 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 1326 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 1327 1328 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL); 1329 if (!ie) { 1330 ret = -ENOMEM; 1331 goto out; 1332 } 1333 1334 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 1335 1336 ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz, 1337 &sched_scan_ies, req->ie, 1338 req->ie_len, bands_used, rate_masks, &chandef, 1339 flags); 1340 1341 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies); 1342 if (ret == 0) { 1343 rcu_assign_pointer(local->sched_scan_sdata, sdata); 1344 rcu_assign_pointer(local->sched_scan_req, req); 1345 } 1346 1347 kfree(ie); 1348 1349 out: 1350 if (ret) { 1351 /* Clean in case of failure after HW restart or upon resume. */ 1352 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1353 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1354 } 1355 1356 return ret; 1357 } 1358 1359 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1360 struct cfg80211_sched_scan_request *req) 1361 { 1362 struct ieee80211_local *local = sdata->local; 1363 int ret; 1364 1365 mutex_lock(&local->mtx); 1366 1367 if (rcu_access_pointer(local->sched_scan_sdata)) { 1368 mutex_unlock(&local->mtx); 1369 return -EBUSY; 1370 } 1371 1372 ret = __ieee80211_request_sched_scan_start(sdata, req); 1373 1374 mutex_unlock(&local->mtx); 1375 return ret; 1376 } 1377 1378 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local) 1379 { 1380 struct ieee80211_sub_if_data *sched_scan_sdata; 1381 int ret = -ENOENT; 1382 1383 mutex_lock(&local->mtx); 1384 1385 if (!local->ops->sched_scan_stop) { 1386 ret = -ENOTSUPP; 1387 goto out; 1388 } 1389 1390 /* We don't want to restart sched scan anymore. */ 1391 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1392 1393 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata, 1394 lockdep_is_held(&local->mtx)); 1395 if (sched_scan_sdata) { 1396 ret = drv_sched_scan_stop(local, sched_scan_sdata); 1397 if (!ret) 1398 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1399 } 1400 out: 1401 mutex_unlock(&local->mtx); 1402 1403 return ret; 1404 } 1405 1406 void ieee80211_sched_scan_results(struct ieee80211_hw *hw) 1407 { 1408 struct ieee80211_local *local = hw_to_local(hw); 1409 1410 trace_api_sched_scan_results(local); 1411 1412 cfg80211_sched_scan_results(hw->wiphy, 0); 1413 } 1414 EXPORT_SYMBOL(ieee80211_sched_scan_results); 1415 1416 void ieee80211_sched_scan_end(struct ieee80211_local *local) 1417 { 1418 mutex_lock(&local->mtx); 1419 1420 if (!rcu_access_pointer(local->sched_scan_sdata)) { 1421 mutex_unlock(&local->mtx); 1422 return; 1423 } 1424 1425 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1426 1427 /* If sched scan was aborted by the driver. */ 1428 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1429 1430 mutex_unlock(&local->mtx); 1431 1432 cfg80211_sched_scan_stopped_locked(local->hw.wiphy, 0); 1433 } 1434 1435 void ieee80211_sched_scan_stopped_work(struct wiphy *wiphy, 1436 struct wiphy_work *work) 1437 { 1438 struct ieee80211_local *local = 1439 container_of(work, struct ieee80211_local, 1440 sched_scan_stopped_work); 1441 1442 ieee80211_sched_scan_end(local); 1443 } 1444 1445 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw) 1446 { 1447 struct ieee80211_local *local = hw_to_local(hw); 1448 1449 trace_api_sched_scan_stopped(local); 1450 1451 /* 1452 * this shouldn't really happen, so for simplicity 1453 * simply ignore it, and let mac80211 reconfigure 1454 * the sched scan later on. 1455 */ 1456 if (local->in_reconfig) 1457 return; 1458 1459 wiphy_work_queue(hw->wiphy, &local->sched_scan_stopped_work); 1460 } 1461 EXPORT_SYMBOL(ieee80211_sched_scan_stopped); 1462