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; 350 u32 *n_chans; 351 u32 flags = 0; 352 353 req = rcu_dereference_protected(local->scan_req, 354 lockdep_is_held(&local->mtx)); 355 356 if (test_bit(SCAN_HW_CANCELLED, &local->scanning)) 357 return false; 358 359 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 360 local->hw_scan_req->req.n_channels = req->n_channels; 361 362 for (i = 0; i < req->n_channels; i++) { 363 local->hw_scan_req->req.channels[i] = req->channels[i]; 364 bands_used |= BIT(req->channels[i]->band); 365 } 366 } else { 367 do { 368 if (local->hw_scan_band == NUM_NL80211_BANDS) 369 return false; 370 371 n_chans = &local->hw_scan_req->req.n_channels; 372 *n_chans = 0; 373 374 for (i = 0; i < req->n_channels; i++) { 375 if (req->channels[i]->band != 376 local->hw_scan_band) 377 continue; 378 local->hw_scan_req->req.channels[(*n_chans)++] = 379 req->channels[i]; 380 381 bands_used |= BIT(req->channels[i]->band); 382 } 383 384 local->hw_scan_band++; 385 } while (!*n_chans); 386 } 387 388 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 389 390 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 391 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 392 393 ielen = ieee80211_build_preq_ies(sdata, 394 (u8 *)local->hw_scan_req->req.ie, 395 local->hw_scan_ies_bufsize, 396 &local->hw_scan_req->ies, 397 req->ie, req->ie_len, 398 bands_used, req->rates, &chandef, 399 flags); 400 local->hw_scan_req->req.ie_len = ielen; 401 local->hw_scan_req->req.no_cck = req->no_cck; 402 ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr); 403 ether_addr_copy(local->hw_scan_req->req.mac_addr_mask, 404 req->mac_addr_mask); 405 ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid); 406 407 return true; 408 } 409 410 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) 411 { 412 struct ieee80211_local *local = hw_to_local(hw); 413 bool hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); 414 bool was_scanning = local->scanning; 415 struct cfg80211_scan_request *scan_req; 416 struct ieee80211_sub_if_data *scan_sdata; 417 struct ieee80211_sub_if_data *sdata; 418 419 lockdep_assert_held(&local->mtx); 420 421 /* 422 * It's ok to abort a not-yet-running scan (that 423 * we have one at all will be verified by checking 424 * local->scan_req next), but not to complete it 425 * successfully. 426 */ 427 if (WARN_ON(!local->scanning && !aborted)) 428 aborted = true; 429 430 if (WARN_ON(!local->scan_req)) 431 return; 432 433 scan_sdata = rcu_dereference_protected(local->scan_sdata, 434 lockdep_is_held(&local->mtx)); 435 436 if (hw_scan && !aborted && 437 !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) && 438 ieee80211_prep_hw_scan(scan_sdata)) { 439 int rc; 440 441 rc = drv_hw_scan(local, 442 rcu_dereference_protected(local->scan_sdata, 443 lockdep_is_held(&local->mtx)), 444 local->hw_scan_req); 445 446 if (rc == 0) 447 return; 448 449 /* HW scan failed and is going to be reported as aborted, 450 * so clear old scan info. 451 */ 452 memset(&local->scan_info, 0, sizeof(local->scan_info)); 453 aborted = true; 454 } 455 456 kfree(local->hw_scan_req); 457 local->hw_scan_req = NULL; 458 459 scan_req = rcu_dereference_protected(local->scan_req, 460 lockdep_is_held(&local->mtx)); 461 462 RCU_INIT_POINTER(local->scan_req, NULL); 463 RCU_INIT_POINTER(local->scan_sdata, NULL); 464 465 local->scanning = 0; 466 local->scan_chandef.chan = NULL; 467 468 synchronize_rcu(); 469 470 if (scan_req != local->int_scan_req) { 471 local->scan_info.aborted = aborted; 472 cfg80211_scan_done(scan_req, &local->scan_info); 473 } 474 475 /* Set power back to normal operating levels. */ 476 ieee80211_hw_config(local, 0); 477 478 if (!hw_scan && was_scanning) { 479 ieee80211_configure_filter(local); 480 drv_sw_scan_complete(local, scan_sdata); 481 ieee80211_offchannel_return(local); 482 } 483 484 ieee80211_recalc_idle(local); 485 486 ieee80211_mlme_notify_scan_completed(local); 487 ieee80211_ibss_notify_scan_completed(local); 488 489 /* Requeue all the work that might have been ignored while 490 * the scan was in progress; if there was none this will 491 * just be a no-op for the particular interface. 492 */ 493 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 494 if (ieee80211_sdata_running(sdata)) 495 wiphy_work_queue(sdata->local->hw.wiphy, &sdata->work); 496 } 497 498 if (was_scanning) 499 ieee80211_start_next_roc(local); 500 } 501 502 void ieee80211_scan_completed(struct ieee80211_hw *hw, 503 struct cfg80211_scan_info *info) 504 { 505 struct ieee80211_local *local = hw_to_local(hw); 506 507 trace_api_scan_completed(local, info->aborted); 508 509 set_bit(SCAN_COMPLETED, &local->scanning); 510 if (info->aborted) 511 set_bit(SCAN_ABORTED, &local->scanning); 512 513 memcpy(&local->scan_info, info, sizeof(*info)); 514 515 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 0); 516 } 517 EXPORT_SYMBOL(ieee80211_scan_completed); 518 519 static int ieee80211_start_sw_scan(struct ieee80211_local *local, 520 struct ieee80211_sub_if_data *sdata) 521 { 522 /* Software scan is not supported in multi-channel cases */ 523 if (local->use_chanctx) 524 return -EOPNOTSUPP; 525 526 /* 527 * Hardware/driver doesn't support hw_scan, so use software 528 * scanning instead. First send a nullfunc frame with power save 529 * bit on so that AP will buffer the frames for us while we are not 530 * listening, then send probe requests to each channel and wait for 531 * the responses. After all channels are scanned, tune back to the 532 * original channel and send a nullfunc frame with power save bit 533 * off to trigger the AP to send us all the buffered frames. 534 * 535 * Note that while local->sw_scanning is true everything else but 536 * nullfunc frames and probe requests will be dropped in 537 * ieee80211_tx_h_check_assoc(). 538 */ 539 drv_sw_scan_start(local, sdata, local->scan_addr); 540 541 local->leave_oper_channel_time = jiffies; 542 local->next_scan_state = SCAN_DECISION; 543 local->scan_channel_idx = 0; 544 545 ieee80211_offchannel_stop_vifs(local); 546 547 /* ensure nullfunc is transmitted before leaving operating channel */ 548 ieee80211_flush_queues(local, NULL, false); 549 550 ieee80211_configure_filter(local); 551 552 /* We need to set power level at maximum rate for scanning. */ 553 ieee80211_hw_config(local, 0); 554 555 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 0); 556 557 return 0; 558 } 559 560 static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata) 561 { 562 struct ieee80211_local *local = sdata->local; 563 struct ieee80211_sub_if_data *sdata_iter; 564 565 if (!ieee80211_is_radar_required(local)) 566 return true; 567 568 if (!regulatory_pre_cac_allowed(local->hw.wiphy)) 569 return false; 570 571 mutex_lock(&local->iflist_mtx); 572 list_for_each_entry(sdata_iter, &local->interfaces, list) { 573 if (sdata_iter->wdev.cac_started) { 574 mutex_unlock(&local->iflist_mtx); 575 return false; 576 } 577 } 578 mutex_unlock(&local->iflist_mtx); 579 580 return true; 581 } 582 583 static bool ieee80211_can_scan(struct ieee80211_local *local, 584 struct ieee80211_sub_if_data *sdata) 585 { 586 if (!__ieee80211_can_leave_ch(sdata)) 587 return false; 588 589 if (!list_empty(&local->roc_list)) 590 return false; 591 592 if (sdata->vif.type == NL80211_IFTYPE_STATION && 593 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL) 594 return false; 595 596 return true; 597 } 598 599 void ieee80211_run_deferred_scan(struct ieee80211_local *local) 600 { 601 lockdep_assert_held(&local->mtx); 602 603 if (!local->scan_req || local->scanning) 604 return; 605 606 if (!ieee80211_can_scan(local, 607 rcu_dereference_protected( 608 local->scan_sdata, 609 lockdep_is_held(&local->mtx)))) 610 return; 611 612 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 613 round_jiffies_relative(0)); 614 } 615 616 static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata, 617 const u8 *src, const u8 *dst, 618 const u8 *ssid, size_t ssid_len, 619 const u8 *ie, size_t ie_len, 620 u32 ratemask, u32 flags, u32 tx_flags, 621 struct ieee80211_channel *channel) 622 { 623 struct sk_buff *skb; 624 625 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel, 626 ssid, ssid_len, 627 ie, ie_len, flags); 628 629 if (skb) { 630 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) { 631 struct ieee80211_hdr *hdr = (void *)skb->data; 632 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 633 u16 sn = get_random_u16(); 634 635 info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO; 636 hdr->seq_ctrl = 637 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn)); 638 } 639 IEEE80211_SKB_CB(skb)->flags |= tx_flags; 640 IEEE80211_SKB_CB(skb)->control.flags |= IEEE80211_TX_CTRL_DONT_USE_RATE_MASK; 641 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band); 642 } 643 } 644 645 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, 646 unsigned long *next_delay) 647 { 648 int i; 649 struct ieee80211_sub_if_data *sdata; 650 struct cfg80211_scan_request *scan_req; 651 enum nl80211_band band = local->hw.conf.chandef.chan->band; 652 u32 flags = 0, tx_flags; 653 654 scan_req = rcu_dereference_protected(local->scan_req, 655 lockdep_is_held(&local->mtx)); 656 657 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK; 658 if (scan_req->no_cck) 659 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE; 660 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 661 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 662 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN) 663 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN; 664 665 sdata = rcu_dereference_protected(local->scan_sdata, 666 lockdep_is_held(&local->mtx)); 667 668 for (i = 0; i < scan_req->n_ssids; i++) 669 ieee80211_send_scan_probe_req( 670 sdata, local->scan_addr, scan_req->bssid, 671 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len, 672 scan_req->ie, scan_req->ie_len, 673 scan_req->rates[band], flags, 674 tx_flags, local->hw.conf.chandef.chan); 675 676 /* 677 * After sending probe requests, wait for probe responses 678 * on the channel. 679 */ 680 *next_delay = IEEE80211_CHANNEL_TIME; 681 local->next_scan_state = SCAN_DECISION; 682 } 683 684 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, 685 struct cfg80211_scan_request *req) 686 { 687 struct ieee80211_local *local = sdata->local; 688 bool hw_scan = local->ops->hw_scan; 689 int rc; 690 691 lockdep_assert_held(&local->mtx); 692 693 if (local->scan_req) 694 return -EBUSY; 695 696 if (!__ieee80211_can_leave_ch(sdata)) 697 return -EBUSY; 698 699 if (!ieee80211_can_scan(local, sdata)) { 700 /* wait for the work to finish/time out */ 701 rcu_assign_pointer(local->scan_req, req); 702 rcu_assign_pointer(local->scan_sdata, sdata); 703 return 0; 704 } 705 706 again: 707 if (hw_scan) { 708 u8 *ies; 709 710 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len; 711 712 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 713 int i, n_bands = 0; 714 u8 bands_counted = 0; 715 716 for (i = 0; i < req->n_channels; i++) { 717 if (bands_counted & BIT(req->channels[i]->band)) 718 continue; 719 bands_counted |= BIT(req->channels[i]->band); 720 n_bands++; 721 } 722 723 local->hw_scan_ies_bufsize *= n_bands; 724 } 725 726 local->hw_scan_req = kmalloc(struct_size(local->hw_scan_req, 727 req.channels, 728 req->n_channels) + 729 local->hw_scan_ies_bufsize, 730 GFP_KERNEL); 731 if (!local->hw_scan_req) 732 return -ENOMEM; 733 734 local->hw_scan_req->req.ssids = req->ssids; 735 local->hw_scan_req->req.n_ssids = req->n_ssids; 736 /* None of the channels are actually set 737 * up but let UBSAN know the boundaries. 738 */ 739 local->hw_scan_req->req.n_channels = req->n_channels; 740 741 ies = (u8 *)local->hw_scan_req + 742 sizeof(*local->hw_scan_req) + 743 req->n_channels * sizeof(req->channels[0]); 744 local->hw_scan_req->req.ie = ies; 745 local->hw_scan_req->req.flags = req->flags; 746 eth_broadcast_addr(local->hw_scan_req->req.bssid); 747 local->hw_scan_req->req.duration = req->duration; 748 local->hw_scan_req->req.duration_mandatory = 749 req->duration_mandatory; 750 751 local->hw_scan_band = 0; 752 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params; 753 local->hw_scan_req->req.scan_6ghz_params = 754 req->scan_6ghz_params; 755 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz; 756 757 /* 758 * After allocating local->hw_scan_req, we must 759 * go through until ieee80211_prep_hw_scan(), so 760 * anything that might be changed here and leave 761 * this function early must not go after this 762 * allocation. 763 */ 764 } 765 766 rcu_assign_pointer(local->scan_req, req); 767 rcu_assign_pointer(local->scan_sdata, sdata); 768 769 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 770 get_random_mask_addr(local->scan_addr, 771 req->mac_addr, 772 req->mac_addr_mask); 773 else 774 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN); 775 776 if (hw_scan) { 777 __set_bit(SCAN_HW_SCANNING, &local->scanning); 778 } else if ((req->n_channels == 1) && 779 (req->channels[0] == local->_oper_chandef.chan)) { 780 /* 781 * If we are scanning only on the operating channel 782 * then we do not need to stop normal activities 783 */ 784 unsigned long next_delay; 785 786 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning); 787 788 ieee80211_recalc_idle(local); 789 790 /* Notify driver scan is starting, keep order of operations 791 * same as normal software scan, in case that matters. */ 792 drv_sw_scan_start(local, sdata, local->scan_addr); 793 794 ieee80211_configure_filter(local); /* accept probe-responses */ 795 796 /* We need to ensure power level is at max for scanning. */ 797 ieee80211_hw_config(local, 0); 798 799 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR | 800 IEEE80211_CHAN_RADAR)) || 801 !req->n_ssids) { 802 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 803 if (req->n_ssids) 804 set_bit(SCAN_BEACON_WAIT, &local->scanning); 805 } else { 806 ieee80211_scan_state_send_probe(local, &next_delay); 807 next_delay = IEEE80211_CHANNEL_TIME; 808 } 809 810 /* Now, just wait a bit and we are all done! */ 811 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 812 next_delay); 813 return 0; 814 } else { 815 /* Do normal software scan */ 816 __set_bit(SCAN_SW_SCANNING, &local->scanning); 817 } 818 819 ieee80211_recalc_idle(local); 820 821 if (hw_scan) { 822 WARN_ON(!ieee80211_prep_hw_scan(sdata)); 823 rc = drv_hw_scan(local, sdata, local->hw_scan_req); 824 } else { 825 rc = ieee80211_start_sw_scan(local, sdata); 826 } 827 828 if (rc) { 829 kfree(local->hw_scan_req); 830 local->hw_scan_req = NULL; 831 local->scanning = 0; 832 833 ieee80211_recalc_idle(local); 834 835 local->scan_req = NULL; 836 RCU_INIT_POINTER(local->scan_sdata, NULL); 837 } 838 839 if (hw_scan && rc == 1) { 840 /* 841 * we can't fall back to software for P2P-GO 842 * as it must update NoA etc. 843 */ 844 if (ieee80211_vif_type_p2p(&sdata->vif) == 845 NL80211_IFTYPE_P2P_GO) 846 return -EOPNOTSUPP; 847 hw_scan = false; 848 goto again; 849 } 850 851 return rc; 852 } 853 854 static unsigned long 855 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) 856 { 857 /* 858 * TODO: channel switching also consumes quite some time, 859 * add that delay as well to get a better estimation 860 */ 861 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) 862 return IEEE80211_PASSIVE_CHANNEL_TIME; 863 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; 864 } 865 866 static void ieee80211_scan_state_decision(struct ieee80211_local *local, 867 unsigned long *next_delay) 868 { 869 bool associated = false; 870 bool tx_empty = true; 871 bool bad_latency; 872 struct ieee80211_sub_if_data *sdata; 873 struct ieee80211_channel *next_chan; 874 enum mac80211_scan_state next_scan_state; 875 struct cfg80211_scan_request *scan_req; 876 877 /* 878 * check if at least one STA interface is associated, 879 * check if at least one STA interface has pending tx frames 880 * and grab the lowest used beacon interval 881 */ 882 mutex_lock(&local->iflist_mtx); 883 list_for_each_entry(sdata, &local->interfaces, list) { 884 if (!ieee80211_sdata_running(sdata)) 885 continue; 886 887 if (sdata->vif.type == NL80211_IFTYPE_STATION) { 888 if (sdata->u.mgd.associated) { 889 associated = true; 890 891 if (!qdisc_all_tx_empty(sdata->dev)) { 892 tx_empty = false; 893 break; 894 } 895 } 896 } 897 } 898 mutex_unlock(&local->iflist_mtx); 899 900 scan_req = rcu_dereference_protected(local->scan_req, 901 lockdep_is_held(&local->mtx)); 902 903 next_chan = scan_req->channels[local->scan_channel_idx]; 904 905 /* 906 * we're currently scanning a different channel, let's 907 * see if we can scan another channel without interfering 908 * with the current traffic situation. 909 * 910 * Keep good latency, do not stay off-channel more than 125 ms. 911 */ 912 913 bad_latency = time_after(jiffies + 914 ieee80211_scan_get_channel_time(next_chan), 915 local->leave_oper_channel_time + HZ / 8); 916 917 if (associated && !tx_empty) { 918 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY) 919 next_scan_state = SCAN_ABORT; 920 else 921 next_scan_state = SCAN_SUSPEND; 922 } else if (associated && bad_latency) { 923 next_scan_state = SCAN_SUSPEND; 924 } else { 925 next_scan_state = SCAN_SET_CHANNEL; 926 } 927 928 local->next_scan_state = next_scan_state; 929 930 *next_delay = 0; 931 } 932 933 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, 934 unsigned long *next_delay) 935 { 936 int skip; 937 struct ieee80211_channel *chan; 938 enum nl80211_bss_scan_width oper_scan_width; 939 struct cfg80211_scan_request *scan_req; 940 941 scan_req = rcu_dereference_protected(local->scan_req, 942 lockdep_is_held(&local->mtx)); 943 944 skip = 0; 945 chan = scan_req->channels[local->scan_channel_idx]; 946 947 local->scan_chandef.chan = chan; 948 local->scan_chandef.center_freq1 = chan->center_freq; 949 local->scan_chandef.freq1_offset = chan->freq_offset; 950 local->scan_chandef.center_freq2 = 0; 951 952 /* For scanning on the S1G band, ignore scan_width (which is constant 953 * across all channels) for now since channel width is specific to each 954 * channel. Detect the required channel width here and likely revisit 955 * later. Maybe scan_width could be used to build the channel scan list? 956 */ 957 if (chan->band == NL80211_BAND_S1GHZ) { 958 local->scan_chandef.width = ieee80211_s1g_channel_width(chan); 959 goto set_channel; 960 } 961 962 switch (scan_req->scan_width) { 963 case NL80211_BSS_CHAN_WIDTH_5: 964 local->scan_chandef.width = NL80211_CHAN_WIDTH_5; 965 break; 966 case NL80211_BSS_CHAN_WIDTH_10: 967 local->scan_chandef.width = NL80211_CHAN_WIDTH_10; 968 break; 969 default: 970 case NL80211_BSS_CHAN_WIDTH_20: 971 /* If scanning on oper channel, use whatever channel-type 972 * is currently in use. 973 */ 974 oper_scan_width = cfg80211_chandef_to_scan_width( 975 &local->_oper_chandef); 976 if (chan == local->_oper_chandef.chan && 977 oper_scan_width == scan_req->scan_width) 978 local->scan_chandef = local->_oper_chandef; 979 else 980 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT; 981 break; 982 case NL80211_BSS_CHAN_WIDTH_1: 983 case NL80211_BSS_CHAN_WIDTH_2: 984 /* shouldn't get here, S1G handled above */ 985 WARN_ON(1); 986 break; 987 } 988 989 set_channel: 990 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) 991 skip = 1; 992 993 /* advance state machine to next channel/band */ 994 local->scan_channel_idx++; 995 996 if (skip) { 997 /* if we skip this channel return to the decision state */ 998 local->next_scan_state = SCAN_DECISION; 999 return; 1000 } 1001 1002 /* 1003 * Probe delay is used to update the NAV, cf. 11.1.3.2.2 1004 * (which unfortunately doesn't say _why_ step a) is done, 1005 * but it waits for the probe delay or until a frame is 1006 * received - and the received frame would update the NAV). 1007 * For now, we do not support waiting until a frame is 1008 * received. 1009 * 1010 * In any case, it is not necessary for a passive scan. 1011 */ 1012 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) || 1013 !scan_req->n_ssids) { 1014 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 1015 local->next_scan_state = SCAN_DECISION; 1016 if (scan_req->n_ssids) 1017 set_bit(SCAN_BEACON_WAIT, &local->scanning); 1018 return; 1019 } 1020 1021 /* active scan, send probes */ 1022 *next_delay = IEEE80211_PROBE_DELAY; 1023 local->next_scan_state = SCAN_SEND_PROBE; 1024 } 1025 1026 static void ieee80211_scan_state_suspend(struct ieee80211_local *local, 1027 unsigned long *next_delay) 1028 { 1029 /* switch back to the operating channel */ 1030 local->scan_chandef.chan = NULL; 1031 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 1032 1033 /* disable PS */ 1034 ieee80211_offchannel_return(local); 1035 1036 *next_delay = HZ / 5; 1037 /* afterwards, resume scan & go to next channel */ 1038 local->next_scan_state = SCAN_RESUME; 1039 } 1040 1041 static void ieee80211_scan_state_resume(struct ieee80211_local *local, 1042 unsigned long *next_delay) 1043 { 1044 ieee80211_offchannel_stop_vifs(local); 1045 1046 if (local->ops->flush) { 1047 ieee80211_flush_queues(local, NULL, false); 1048 *next_delay = 0; 1049 } else 1050 *next_delay = HZ / 10; 1051 1052 /* remember when we left the operating channel */ 1053 local->leave_oper_channel_time = jiffies; 1054 1055 /* advance to the next channel to be scanned */ 1056 local->next_scan_state = SCAN_SET_CHANNEL; 1057 } 1058 1059 void ieee80211_scan_work(struct wiphy *wiphy, struct wiphy_work *work) 1060 { 1061 struct ieee80211_local *local = 1062 container_of(work, struct ieee80211_local, scan_work.work); 1063 struct ieee80211_sub_if_data *sdata; 1064 struct cfg80211_scan_request *scan_req; 1065 unsigned long next_delay = 0; 1066 bool aborted; 1067 1068 mutex_lock(&local->mtx); 1069 1070 if (!ieee80211_can_run_worker(local)) { 1071 aborted = true; 1072 goto out_complete; 1073 } 1074 1075 sdata = rcu_dereference_protected(local->scan_sdata, 1076 lockdep_is_held(&local->mtx)); 1077 scan_req = rcu_dereference_protected(local->scan_req, 1078 lockdep_is_held(&local->mtx)); 1079 1080 /* When scanning on-channel, the first-callback means completed. */ 1081 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) { 1082 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1083 goto out_complete; 1084 } 1085 1086 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) { 1087 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1088 goto out_complete; 1089 } 1090 1091 if (!sdata || !scan_req) 1092 goto out; 1093 1094 if (!local->scanning) { 1095 int rc; 1096 1097 RCU_INIT_POINTER(local->scan_req, NULL); 1098 RCU_INIT_POINTER(local->scan_sdata, NULL); 1099 1100 rc = __ieee80211_start_scan(sdata, scan_req); 1101 if (rc) { 1102 /* need to complete scan in cfg80211 */ 1103 rcu_assign_pointer(local->scan_req, scan_req); 1104 aborted = true; 1105 goto out_complete; 1106 } else 1107 goto out; 1108 } 1109 1110 clear_bit(SCAN_BEACON_WAIT, &local->scanning); 1111 1112 /* 1113 * as long as no delay is required advance immediately 1114 * without scheduling a new work 1115 */ 1116 do { 1117 if (!ieee80211_sdata_running(sdata)) { 1118 aborted = true; 1119 goto out_complete; 1120 } 1121 1122 if (test_and_clear_bit(SCAN_BEACON_DONE, &local->scanning) && 1123 local->next_scan_state == SCAN_DECISION) 1124 local->next_scan_state = SCAN_SEND_PROBE; 1125 1126 switch (local->next_scan_state) { 1127 case SCAN_DECISION: 1128 /* if no more bands/channels left, complete scan */ 1129 if (local->scan_channel_idx >= scan_req->n_channels) { 1130 aborted = false; 1131 goto out_complete; 1132 } 1133 ieee80211_scan_state_decision(local, &next_delay); 1134 break; 1135 case SCAN_SET_CHANNEL: 1136 ieee80211_scan_state_set_channel(local, &next_delay); 1137 break; 1138 case SCAN_SEND_PROBE: 1139 ieee80211_scan_state_send_probe(local, &next_delay); 1140 break; 1141 case SCAN_SUSPEND: 1142 ieee80211_scan_state_suspend(local, &next_delay); 1143 break; 1144 case SCAN_RESUME: 1145 ieee80211_scan_state_resume(local, &next_delay); 1146 break; 1147 case SCAN_ABORT: 1148 aborted = true; 1149 goto out_complete; 1150 } 1151 } while (next_delay == 0); 1152 1153 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 1154 next_delay); 1155 goto out; 1156 1157 out_complete: 1158 __ieee80211_scan_completed(&local->hw, aborted); 1159 out: 1160 mutex_unlock(&local->mtx); 1161 } 1162 1163 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, 1164 struct cfg80211_scan_request *req) 1165 { 1166 int res; 1167 1168 mutex_lock(&sdata->local->mtx); 1169 res = __ieee80211_start_scan(sdata, req); 1170 mutex_unlock(&sdata->local->mtx); 1171 1172 return res; 1173 } 1174 1175 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata, 1176 const u8 *ssid, u8 ssid_len, 1177 struct ieee80211_channel **channels, 1178 unsigned int n_channels, 1179 enum nl80211_bss_scan_width scan_width) 1180 { 1181 struct ieee80211_local *local = sdata->local; 1182 int ret = -EBUSY, i, n_ch = 0; 1183 enum nl80211_band band; 1184 1185 mutex_lock(&local->mtx); 1186 1187 /* busy scanning */ 1188 if (local->scan_req) 1189 goto unlock; 1190 1191 /* fill internal scan request */ 1192 if (!channels) { 1193 int max_n; 1194 1195 for (band = 0; band < NUM_NL80211_BANDS; band++) { 1196 if (!local->hw.wiphy->bands[band] || 1197 band == NL80211_BAND_6GHZ) 1198 continue; 1199 1200 max_n = local->hw.wiphy->bands[band]->n_channels; 1201 for (i = 0; i < max_n; i++) { 1202 struct ieee80211_channel *tmp_ch = 1203 &local->hw.wiphy->bands[band]->channels[i]; 1204 1205 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR | 1206 IEEE80211_CHAN_DISABLED)) 1207 continue; 1208 1209 local->int_scan_req->channels[n_ch] = tmp_ch; 1210 n_ch++; 1211 } 1212 } 1213 1214 if (WARN_ON_ONCE(n_ch == 0)) 1215 goto unlock; 1216 1217 local->int_scan_req->n_channels = n_ch; 1218 } else { 1219 for (i = 0; i < n_channels; i++) { 1220 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR | 1221 IEEE80211_CHAN_DISABLED)) 1222 continue; 1223 1224 local->int_scan_req->channels[n_ch] = channels[i]; 1225 n_ch++; 1226 } 1227 1228 if (WARN_ON_ONCE(n_ch == 0)) 1229 goto unlock; 1230 1231 local->int_scan_req->n_channels = n_ch; 1232 } 1233 1234 local->int_scan_req->ssids = &local->scan_ssid; 1235 local->int_scan_req->n_ssids = 1; 1236 local->int_scan_req->scan_width = scan_width; 1237 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); 1238 local->int_scan_req->ssids[0].ssid_len = ssid_len; 1239 1240 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); 1241 unlock: 1242 mutex_unlock(&local->mtx); 1243 return ret; 1244 } 1245 1246 void ieee80211_scan_cancel(struct ieee80211_local *local) 1247 { 1248 /* ensure a new scan cannot be queued */ 1249 lockdep_assert_wiphy(local->hw.wiphy); 1250 1251 /* 1252 * We are canceling software scan, or deferred scan that was not 1253 * yet really started (see __ieee80211_start_scan ). 1254 * 1255 * Regarding hardware scan: 1256 * - we can not call __ieee80211_scan_completed() as when 1257 * SCAN_HW_SCANNING bit is set this function change 1258 * local->hw_scan_req to operate on 5G band, what race with 1259 * driver which can use local->hw_scan_req 1260 * 1261 * - we can not cancel scan_work since driver can schedule it 1262 * by ieee80211_scan_completed(..., true) to finish scan 1263 * 1264 * Hence we only call the cancel_hw_scan() callback, but the low-level 1265 * driver is still responsible for calling ieee80211_scan_completed() 1266 * after the scan was completed/aborted. 1267 */ 1268 1269 mutex_lock(&local->mtx); 1270 if (!local->scan_req) 1271 goto out; 1272 1273 /* 1274 * We have a scan running and the driver already reported completion, 1275 * but the worker hasn't run yet or is stuck on the mutex - mark it as 1276 * cancelled. 1277 */ 1278 if (test_bit(SCAN_HW_SCANNING, &local->scanning) && 1279 test_bit(SCAN_COMPLETED, &local->scanning)) { 1280 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1281 goto out; 1282 } 1283 1284 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) { 1285 /* 1286 * Make sure that __ieee80211_scan_completed doesn't trigger a 1287 * scan on another band. 1288 */ 1289 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1290 if (local->ops->cancel_hw_scan) 1291 drv_cancel_hw_scan(local, 1292 rcu_dereference_protected(local->scan_sdata, 1293 lockdep_is_held(&local->mtx))); 1294 goto out; 1295 } 1296 1297 wiphy_delayed_work_cancel(local->hw.wiphy, &local->scan_work); 1298 /* and clean up */ 1299 memset(&local->scan_info, 0, sizeof(local->scan_info)); 1300 __ieee80211_scan_completed(&local->hw, true); 1301 out: 1302 mutex_unlock(&local->mtx); 1303 } 1304 1305 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1306 struct cfg80211_sched_scan_request *req) 1307 { 1308 struct ieee80211_local *local = sdata->local; 1309 struct ieee80211_scan_ies sched_scan_ies = {}; 1310 struct cfg80211_chan_def chandef; 1311 int ret, i, iebufsz, num_bands = 0; 1312 u32 rate_masks[NUM_NL80211_BANDS] = {}; 1313 u8 bands_used = 0; 1314 u8 *ie; 1315 u32 flags = 0; 1316 1317 iebufsz = local->scan_ies_len + req->ie_len; 1318 1319 lockdep_assert_held(&local->mtx); 1320 1321 if (!local->ops->sched_scan_start) 1322 return -ENOTSUPP; 1323 1324 for (i = 0; i < NUM_NL80211_BANDS; i++) { 1325 if (local->hw.wiphy->bands[i]) { 1326 bands_used |= BIT(i); 1327 rate_masks[i] = (u32) -1; 1328 num_bands++; 1329 } 1330 } 1331 1332 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 1333 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 1334 1335 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL); 1336 if (!ie) { 1337 ret = -ENOMEM; 1338 goto out; 1339 } 1340 1341 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 1342 1343 ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz, 1344 &sched_scan_ies, req->ie, 1345 req->ie_len, bands_used, rate_masks, &chandef, 1346 flags); 1347 1348 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies); 1349 if (ret == 0) { 1350 rcu_assign_pointer(local->sched_scan_sdata, sdata); 1351 rcu_assign_pointer(local->sched_scan_req, req); 1352 } 1353 1354 kfree(ie); 1355 1356 out: 1357 if (ret) { 1358 /* Clean in case of failure after HW restart or upon resume. */ 1359 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1360 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1361 } 1362 1363 return ret; 1364 } 1365 1366 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1367 struct cfg80211_sched_scan_request *req) 1368 { 1369 struct ieee80211_local *local = sdata->local; 1370 int ret; 1371 1372 mutex_lock(&local->mtx); 1373 1374 if (rcu_access_pointer(local->sched_scan_sdata)) { 1375 mutex_unlock(&local->mtx); 1376 return -EBUSY; 1377 } 1378 1379 ret = __ieee80211_request_sched_scan_start(sdata, req); 1380 1381 mutex_unlock(&local->mtx); 1382 return ret; 1383 } 1384 1385 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local) 1386 { 1387 struct ieee80211_sub_if_data *sched_scan_sdata; 1388 int ret = -ENOENT; 1389 1390 mutex_lock(&local->mtx); 1391 1392 if (!local->ops->sched_scan_stop) { 1393 ret = -ENOTSUPP; 1394 goto out; 1395 } 1396 1397 /* We don't want to restart sched scan anymore. */ 1398 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1399 1400 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata, 1401 lockdep_is_held(&local->mtx)); 1402 if (sched_scan_sdata) { 1403 ret = drv_sched_scan_stop(local, sched_scan_sdata); 1404 if (!ret) 1405 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1406 } 1407 out: 1408 mutex_unlock(&local->mtx); 1409 1410 return ret; 1411 } 1412 1413 void ieee80211_sched_scan_results(struct ieee80211_hw *hw) 1414 { 1415 struct ieee80211_local *local = hw_to_local(hw); 1416 1417 trace_api_sched_scan_results(local); 1418 1419 cfg80211_sched_scan_results(hw->wiphy, 0); 1420 } 1421 EXPORT_SYMBOL(ieee80211_sched_scan_results); 1422 1423 void ieee80211_sched_scan_end(struct ieee80211_local *local) 1424 { 1425 mutex_lock(&local->mtx); 1426 1427 if (!rcu_access_pointer(local->sched_scan_sdata)) { 1428 mutex_unlock(&local->mtx); 1429 return; 1430 } 1431 1432 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1433 1434 /* If sched scan was aborted by the driver. */ 1435 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1436 1437 mutex_unlock(&local->mtx); 1438 1439 cfg80211_sched_scan_stopped_locked(local->hw.wiphy, 0); 1440 } 1441 1442 void ieee80211_sched_scan_stopped_work(struct wiphy *wiphy, 1443 struct wiphy_work *work) 1444 { 1445 struct ieee80211_local *local = 1446 container_of(work, struct ieee80211_local, 1447 sched_scan_stopped_work); 1448 1449 ieee80211_sched_scan_end(local); 1450 } 1451 1452 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw) 1453 { 1454 struct ieee80211_local *local = hw_to_local(hw); 1455 1456 trace_api_sched_scan_stopped(local); 1457 1458 /* 1459 * this shouldn't really happen, so for simplicity 1460 * simply ignore it, and let mac80211 reconfigure 1461 * the sched scan later on. 1462 */ 1463 if (local->in_reconfig) 1464 return; 1465 1466 wiphy_work_queue(hw->wiphy, &local->sched_scan_stopped_work); 1467 } 1468 EXPORT_SYMBOL(ieee80211_sched_scan_stopped); 1469