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_tx_skb_tid_band(sdata, skb, 7, channel->band); 640 } 641 } 642 643 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, 644 unsigned long *next_delay) 645 { 646 int i; 647 struct ieee80211_sub_if_data *sdata; 648 struct cfg80211_scan_request *scan_req; 649 enum nl80211_band band = local->hw.conf.chandef.chan->band; 650 u32 flags = 0, tx_flags; 651 652 scan_req = rcu_dereference_protected(local->scan_req, 653 lockdep_is_held(&local->mtx)); 654 655 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK; 656 if (scan_req->no_cck) 657 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE; 658 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 659 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 660 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN) 661 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN; 662 663 sdata = rcu_dereference_protected(local->scan_sdata, 664 lockdep_is_held(&local->mtx)); 665 666 for (i = 0; i < scan_req->n_ssids; i++) 667 ieee80211_send_scan_probe_req( 668 sdata, local->scan_addr, scan_req->bssid, 669 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len, 670 scan_req->ie, scan_req->ie_len, 671 scan_req->rates[band], flags, 672 tx_flags, local->hw.conf.chandef.chan); 673 674 /* 675 * After sending probe requests, wait for probe responses 676 * on the channel. 677 */ 678 *next_delay = IEEE80211_CHANNEL_TIME; 679 local->next_scan_state = SCAN_DECISION; 680 } 681 682 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, 683 struct cfg80211_scan_request *req) 684 { 685 struct ieee80211_local *local = sdata->local; 686 bool hw_scan = local->ops->hw_scan; 687 int rc; 688 689 lockdep_assert_held(&local->mtx); 690 691 if (local->scan_req) 692 return -EBUSY; 693 694 if (!__ieee80211_can_leave_ch(sdata)) 695 return -EBUSY; 696 697 if (!ieee80211_can_scan(local, sdata)) { 698 /* wait for the work to finish/time out */ 699 rcu_assign_pointer(local->scan_req, req); 700 rcu_assign_pointer(local->scan_sdata, sdata); 701 return 0; 702 } 703 704 again: 705 if (hw_scan) { 706 u8 *ies; 707 708 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len; 709 710 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 711 int i, n_bands = 0; 712 u8 bands_counted = 0; 713 714 for (i = 0; i < req->n_channels; i++) { 715 if (bands_counted & BIT(req->channels[i]->band)) 716 continue; 717 bands_counted |= BIT(req->channels[i]->band); 718 n_bands++; 719 } 720 721 local->hw_scan_ies_bufsize *= n_bands; 722 } 723 724 local->hw_scan_req = kmalloc( 725 sizeof(*local->hw_scan_req) + 726 req->n_channels * sizeof(req->channels[0]) + 727 local->hw_scan_ies_bufsize, GFP_KERNEL); 728 if (!local->hw_scan_req) 729 return -ENOMEM; 730 731 local->hw_scan_req->req.ssids = req->ssids; 732 local->hw_scan_req->req.n_ssids = req->n_ssids; 733 ies = (u8 *)local->hw_scan_req + 734 sizeof(*local->hw_scan_req) + 735 req->n_channels * sizeof(req->channels[0]); 736 local->hw_scan_req->req.ie = ies; 737 local->hw_scan_req->req.flags = req->flags; 738 eth_broadcast_addr(local->hw_scan_req->req.bssid); 739 local->hw_scan_req->req.duration = req->duration; 740 local->hw_scan_req->req.duration_mandatory = 741 req->duration_mandatory; 742 743 local->hw_scan_band = 0; 744 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params; 745 local->hw_scan_req->req.scan_6ghz_params = 746 req->scan_6ghz_params; 747 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz; 748 749 /* 750 * After allocating local->hw_scan_req, we must 751 * go through until ieee80211_prep_hw_scan(), so 752 * anything that might be changed here and leave 753 * this function early must not go after this 754 * allocation. 755 */ 756 } 757 758 rcu_assign_pointer(local->scan_req, req); 759 rcu_assign_pointer(local->scan_sdata, sdata); 760 761 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 762 get_random_mask_addr(local->scan_addr, 763 req->mac_addr, 764 req->mac_addr_mask); 765 else 766 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN); 767 768 if (hw_scan) { 769 __set_bit(SCAN_HW_SCANNING, &local->scanning); 770 } else if ((req->n_channels == 1) && 771 (req->channels[0] == local->_oper_chandef.chan)) { 772 /* 773 * If we are scanning only on the operating channel 774 * then we do not need to stop normal activities 775 */ 776 unsigned long next_delay; 777 778 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning); 779 780 ieee80211_recalc_idle(local); 781 782 /* Notify driver scan is starting, keep order of operations 783 * same as normal software scan, in case that matters. */ 784 drv_sw_scan_start(local, sdata, local->scan_addr); 785 786 ieee80211_configure_filter(local); /* accept probe-responses */ 787 788 /* We need to ensure power level is at max for scanning. */ 789 ieee80211_hw_config(local, 0); 790 791 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR | 792 IEEE80211_CHAN_RADAR)) || 793 !req->n_ssids) { 794 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 795 if (req->n_ssids) 796 set_bit(SCAN_BEACON_WAIT, &local->scanning); 797 } else { 798 ieee80211_scan_state_send_probe(local, &next_delay); 799 next_delay = IEEE80211_CHANNEL_TIME; 800 } 801 802 /* Now, just wait a bit and we are all done! */ 803 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 804 next_delay); 805 return 0; 806 } else { 807 /* Do normal software scan */ 808 __set_bit(SCAN_SW_SCANNING, &local->scanning); 809 } 810 811 ieee80211_recalc_idle(local); 812 813 if (hw_scan) { 814 WARN_ON(!ieee80211_prep_hw_scan(sdata)); 815 rc = drv_hw_scan(local, sdata, local->hw_scan_req); 816 } else { 817 rc = ieee80211_start_sw_scan(local, sdata); 818 } 819 820 if (rc) { 821 kfree(local->hw_scan_req); 822 local->hw_scan_req = NULL; 823 local->scanning = 0; 824 825 ieee80211_recalc_idle(local); 826 827 local->scan_req = NULL; 828 RCU_INIT_POINTER(local->scan_sdata, NULL); 829 } 830 831 if (hw_scan && rc == 1) { 832 /* 833 * we can't fall back to software for P2P-GO 834 * as it must update NoA etc. 835 */ 836 if (ieee80211_vif_type_p2p(&sdata->vif) == 837 NL80211_IFTYPE_P2P_GO) 838 return -EOPNOTSUPP; 839 hw_scan = false; 840 goto again; 841 } 842 843 return rc; 844 } 845 846 static unsigned long 847 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) 848 { 849 /* 850 * TODO: channel switching also consumes quite some time, 851 * add that delay as well to get a better estimation 852 */ 853 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) 854 return IEEE80211_PASSIVE_CHANNEL_TIME; 855 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; 856 } 857 858 static void ieee80211_scan_state_decision(struct ieee80211_local *local, 859 unsigned long *next_delay) 860 { 861 bool associated = false; 862 bool tx_empty = true; 863 bool bad_latency; 864 struct ieee80211_sub_if_data *sdata; 865 struct ieee80211_channel *next_chan; 866 enum mac80211_scan_state next_scan_state; 867 struct cfg80211_scan_request *scan_req; 868 869 /* 870 * check if at least one STA interface is associated, 871 * check if at least one STA interface has pending tx frames 872 * and grab the lowest used beacon interval 873 */ 874 mutex_lock(&local->iflist_mtx); 875 list_for_each_entry(sdata, &local->interfaces, list) { 876 if (!ieee80211_sdata_running(sdata)) 877 continue; 878 879 if (sdata->vif.type == NL80211_IFTYPE_STATION) { 880 if (sdata->u.mgd.associated) { 881 associated = true; 882 883 if (!qdisc_all_tx_empty(sdata->dev)) { 884 tx_empty = false; 885 break; 886 } 887 } 888 } 889 } 890 mutex_unlock(&local->iflist_mtx); 891 892 scan_req = rcu_dereference_protected(local->scan_req, 893 lockdep_is_held(&local->mtx)); 894 895 next_chan = scan_req->channels[local->scan_channel_idx]; 896 897 /* 898 * we're currently scanning a different channel, let's 899 * see if we can scan another channel without interfering 900 * with the current traffic situation. 901 * 902 * Keep good latency, do not stay off-channel more than 125 ms. 903 */ 904 905 bad_latency = time_after(jiffies + 906 ieee80211_scan_get_channel_time(next_chan), 907 local->leave_oper_channel_time + HZ / 8); 908 909 if (associated && !tx_empty) { 910 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY) 911 next_scan_state = SCAN_ABORT; 912 else 913 next_scan_state = SCAN_SUSPEND; 914 } else if (associated && bad_latency) { 915 next_scan_state = SCAN_SUSPEND; 916 } else { 917 next_scan_state = SCAN_SET_CHANNEL; 918 } 919 920 local->next_scan_state = next_scan_state; 921 922 *next_delay = 0; 923 } 924 925 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, 926 unsigned long *next_delay) 927 { 928 int skip; 929 struct ieee80211_channel *chan; 930 enum nl80211_bss_scan_width oper_scan_width; 931 struct cfg80211_scan_request *scan_req; 932 933 scan_req = rcu_dereference_protected(local->scan_req, 934 lockdep_is_held(&local->mtx)); 935 936 skip = 0; 937 chan = scan_req->channels[local->scan_channel_idx]; 938 939 local->scan_chandef.chan = chan; 940 local->scan_chandef.center_freq1 = chan->center_freq; 941 local->scan_chandef.freq1_offset = chan->freq_offset; 942 local->scan_chandef.center_freq2 = 0; 943 944 /* For scanning on the S1G band, ignore scan_width (which is constant 945 * across all channels) for now since channel width is specific to each 946 * channel. Detect the required channel width here and likely revisit 947 * later. Maybe scan_width could be used to build the channel scan list? 948 */ 949 if (chan->band == NL80211_BAND_S1GHZ) { 950 local->scan_chandef.width = ieee80211_s1g_channel_width(chan); 951 goto set_channel; 952 } 953 954 switch (scan_req->scan_width) { 955 case NL80211_BSS_CHAN_WIDTH_5: 956 local->scan_chandef.width = NL80211_CHAN_WIDTH_5; 957 break; 958 case NL80211_BSS_CHAN_WIDTH_10: 959 local->scan_chandef.width = NL80211_CHAN_WIDTH_10; 960 break; 961 default: 962 case NL80211_BSS_CHAN_WIDTH_20: 963 /* If scanning on oper channel, use whatever channel-type 964 * is currently in use. 965 */ 966 oper_scan_width = cfg80211_chandef_to_scan_width( 967 &local->_oper_chandef); 968 if (chan == local->_oper_chandef.chan && 969 oper_scan_width == scan_req->scan_width) 970 local->scan_chandef = local->_oper_chandef; 971 else 972 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT; 973 break; 974 case NL80211_BSS_CHAN_WIDTH_1: 975 case NL80211_BSS_CHAN_WIDTH_2: 976 /* shouldn't get here, S1G handled above */ 977 WARN_ON(1); 978 break; 979 } 980 981 set_channel: 982 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) 983 skip = 1; 984 985 /* advance state machine to next channel/band */ 986 local->scan_channel_idx++; 987 988 if (skip) { 989 /* if we skip this channel return to the decision state */ 990 local->next_scan_state = SCAN_DECISION; 991 return; 992 } 993 994 /* 995 * Probe delay is used to update the NAV, cf. 11.1.3.2.2 996 * (which unfortunately doesn't say _why_ step a) is done, 997 * but it waits for the probe delay or until a frame is 998 * received - and the received frame would update the NAV). 999 * For now, we do not support waiting until a frame is 1000 * received. 1001 * 1002 * In any case, it is not necessary for a passive scan. 1003 */ 1004 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) || 1005 !scan_req->n_ssids) { 1006 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 1007 local->next_scan_state = SCAN_DECISION; 1008 if (scan_req->n_ssids) 1009 set_bit(SCAN_BEACON_WAIT, &local->scanning); 1010 return; 1011 } 1012 1013 /* active scan, send probes */ 1014 *next_delay = IEEE80211_PROBE_DELAY; 1015 local->next_scan_state = SCAN_SEND_PROBE; 1016 } 1017 1018 static void ieee80211_scan_state_suspend(struct ieee80211_local *local, 1019 unsigned long *next_delay) 1020 { 1021 /* switch back to the operating channel */ 1022 local->scan_chandef.chan = NULL; 1023 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 1024 1025 /* disable PS */ 1026 ieee80211_offchannel_return(local); 1027 1028 *next_delay = HZ / 5; 1029 /* afterwards, resume scan & go to next channel */ 1030 local->next_scan_state = SCAN_RESUME; 1031 } 1032 1033 static void ieee80211_scan_state_resume(struct ieee80211_local *local, 1034 unsigned long *next_delay) 1035 { 1036 ieee80211_offchannel_stop_vifs(local); 1037 1038 if (local->ops->flush) { 1039 ieee80211_flush_queues(local, NULL, false); 1040 *next_delay = 0; 1041 } else 1042 *next_delay = HZ / 10; 1043 1044 /* remember when we left the operating channel */ 1045 local->leave_oper_channel_time = jiffies; 1046 1047 /* advance to the next channel to be scanned */ 1048 local->next_scan_state = SCAN_SET_CHANNEL; 1049 } 1050 1051 void ieee80211_scan_work(struct wiphy *wiphy, struct wiphy_work *work) 1052 { 1053 struct ieee80211_local *local = 1054 container_of(work, struct ieee80211_local, scan_work.work); 1055 struct ieee80211_sub_if_data *sdata; 1056 struct cfg80211_scan_request *scan_req; 1057 unsigned long next_delay = 0; 1058 bool aborted; 1059 1060 mutex_lock(&local->mtx); 1061 1062 if (!ieee80211_can_run_worker(local)) { 1063 aborted = true; 1064 goto out_complete; 1065 } 1066 1067 sdata = rcu_dereference_protected(local->scan_sdata, 1068 lockdep_is_held(&local->mtx)); 1069 scan_req = rcu_dereference_protected(local->scan_req, 1070 lockdep_is_held(&local->mtx)); 1071 1072 /* When scanning on-channel, the first-callback means completed. */ 1073 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) { 1074 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1075 goto out_complete; 1076 } 1077 1078 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) { 1079 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1080 goto out_complete; 1081 } 1082 1083 if (!sdata || !scan_req) 1084 goto out; 1085 1086 if (!local->scanning) { 1087 int rc; 1088 1089 RCU_INIT_POINTER(local->scan_req, NULL); 1090 RCU_INIT_POINTER(local->scan_sdata, NULL); 1091 1092 rc = __ieee80211_start_scan(sdata, scan_req); 1093 if (rc) { 1094 /* need to complete scan in cfg80211 */ 1095 rcu_assign_pointer(local->scan_req, scan_req); 1096 aborted = true; 1097 goto out_complete; 1098 } else 1099 goto out; 1100 } 1101 1102 clear_bit(SCAN_BEACON_WAIT, &local->scanning); 1103 1104 /* 1105 * as long as no delay is required advance immediately 1106 * without scheduling a new work 1107 */ 1108 do { 1109 if (!ieee80211_sdata_running(sdata)) { 1110 aborted = true; 1111 goto out_complete; 1112 } 1113 1114 if (test_and_clear_bit(SCAN_BEACON_DONE, &local->scanning) && 1115 local->next_scan_state == SCAN_DECISION) 1116 local->next_scan_state = SCAN_SEND_PROBE; 1117 1118 switch (local->next_scan_state) { 1119 case SCAN_DECISION: 1120 /* if no more bands/channels left, complete scan */ 1121 if (local->scan_channel_idx >= scan_req->n_channels) { 1122 aborted = false; 1123 goto out_complete; 1124 } 1125 ieee80211_scan_state_decision(local, &next_delay); 1126 break; 1127 case SCAN_SET_CHANNEL: 1128 ieee80211_scan_state_set_channel(local, &next_delay); 1129 break; 1130 case SCAN_SEND_PROBE: 1131 ieee80211_scan_state_send_probe(local, &next_delay); 1132 break; 1133 case SCAN_SUSPEND: 1134 ieee80211_scan_state_suspend(local, &next_delay); 1135 break; 1136 case SCAN_RESUME: 1137 ieee80211_scan_state_resume(local, &next_delay); 1138 break; 1139 case SCAN_ABORT: 1140 aborted = true; 1141 goto out_complete; 1142 } 1143 } while (next_delay == 0); 1144 1145 wiphy_delayed_work_queue(local->hw.wiphy, &local->scan_work, 1146 next_delay); 1147 goto out; 1148 1149 out_complete: 1150 __ieee80211_scan_completed(&local->hw, aborted); 1151 out: 1152 mutex_unlock(&local->mtx); 1153 } 1154 1155 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, 1156 struct cfg80211_scan_request *req) 1157 { 1158 int res; 1159 1160 mutex_lock(&sdata->local->mtx); 1161 res = __ieee80211_start_scan(sdata, req); 1162 mutex_unlock(&sdata->local->mtx); 1163 1164 return res; 1165 } 1166 1167 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata, 1168 const u8 *ssid, u8 ssid_len, 1169 struct ieee80211_channel **channels, 1170 unsigned int n_channels, 1171 enum nl80211_bss_scan_width scan_width) 1172 { 1173 struct ieee80211_local *local = sdata->local; 1174 int ret = -EBUSY, i, n_ch = 0; 1175 enum nl80211_band band; 1176 1177 mutex_lock(&local->mtx); 1178 1179 /* busy scanning */ 1180 if (local->scan_req) 1181 goto unlock; 1182 1183 /* fill internal scan request */ 1184 if (!channels) { 1185 int max_n; 1186 1187 for (band = 0; band < NUM_NL80211_BANDS; band++) { 1188 if (!local->hw.wiphy->bands[band] || 1189 band == NL80211_BAND_6GHZ) 1190 continue; 1191 1192 max_n = local->hw.wiphy->bands[band]->n_channels; 1193 for (i = 0; i < max_n; i++) { 1194 struct ieee80211_channel *tmp_ch = 1195 &local->hw.wiphy->bands[band]->channels[i]; 1196 1197 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR | 1198 IEEE80211_CHAN_DISABLED)) 1199 continue; 1200 1201 local->int_scan_req->channels[n_ch] = tmp_ch; 1202 n_ch++; 1203 } 1204 } 1205 1206 if (WARN_ON_ONCE(n_ch == 0)) 1207 goto unlock; 1208 1209 local->int_scan_req->n_channels = n_ch; 1210 } else { 1211 for (i = 0; i < n_channels; i++) { 1212 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR | 1213 IEEE80211_CHAN_DISABLED)) 1214 continue; 1215 1216 local->int_scan_req->channels[n_ch] = channels[i]; 1217 n_ch++; 1218 } 1219 1220 if (WARN_ON_ONCE(n_ch == 0)) 1221 goto unlock; 1222 1223 local->int_scan_req->n_channels = n_ch; 1224 } 1225 1226 local->int_scan_req->ssids = &local->scan_ssid; 1227 local->int_scan_req->n_ssids = 1; 1228 local->int_scan_req->scan_width = scan_width; 1229 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); 1230 local->int_scan_req->ssids[0].ssid_len = ssid_len; 1231 1232 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); 1233 unlock: 1234 mutex_unlock(&local->mtx); 1235 return ret; 1236 } 1237 1238 void ieee80211_scan_cancel(struct ieee80211_local *local) 1239 { 1240 /* ensure a new scan cannot be queued */ 1241 lockdep_assert_wiphy(local->hw.wiphy); 1242 1243 /* 1244 * We are canceling software scan, or deferred scan that was not 1245 * yet really started (see __ieee80211_start_scan ). 1246 * 1247 * Regarding hardware scan: 1248 * - we can not call __ieee80211_scan_completed() as when 1249 * SCAN_HW_SCANNING bit is set this function change 1250 * local->hw_scan_req to operate on 5G band, what race with 1251 * driver which can use local->hw_scan_req 1252 * 1253 * - we can not cancel scan_work since driver can schedule it 1254 * by ieee80211_scan_completed(..., true) to finish scan 1255 * 1256 * Hence we only call the cancel_hw_scan() callback, but the low-level 1257 * driver is still responsible for calling ieee80211_scan_completed() 1258 * after the scan was completed/aborted. 1259 */ 1260 1261 mutex_lock(&local->mtx); 1262 if (!local->scan_req) 1263 goto out; 1264 1265 /* 1266 * We have a scan running and the driver already reported completion, 1267 * but the worker hasn't run yet or is stuck on the mutex - mark it as 1268 * cancelled. 1269 */ 1270 if (test_bit(SCAN_HW_SCANNING, &local->scanning) && 1271 test_bit(SCAN_COMPLETED, &local->scanning)) { 1272 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1273 goto out; 1274 } 1275 1276 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) { 1277 /* 1278 * Make sure that __ieee80211_scan_completed doesn't trigger a 1279 * scan on another band. 1280 */ 1281 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1282 if (local->ops->cancel_hw_scan) 1283 drv_cancel_hw_scan(local, 1284 rcu_dereference_protected(local->scan_sdata, 1285 lockdep_is_held(&local->mtx))); 1286 goto out; 1287 } 1288 1289 wiphy_delayed_work_cancel(local->hw.wiphy, &local->scan_work); 1290 /* and clean up */ 1291 memset(&local->scan_info, 0, sizeof(local->scan_info)); 1292 __ieee80211_scan_completed(&local->hw, true); 1293 out: 1294 mutex_unlock(&local->mtx); 1295 } 1296 1297 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1298 struct cfg80211_sched_scan_request *req) 1299 { 1300 struct ieee80211_local *local = sdata->local; 1301 struct ieee80211_scan_ies sched_scan_ies = {}; 1302 struct cfg80211_chan_def chandef; 1303 int ret, i, iebufsz, num_bands = 0; 1304 u32 rate_masks[NUM_NL80211_BANDS] = {}; 1305 u8 bands_used = 0; 1306 u8 *ie; 1307 u32 flags = 0; 1308 1309 iebufsz = local->scan_ies_len + req->ie_len; 1310 1311 lockdep_assert_held(&local->mtx); 1312 1313 if (!local->ops->sched_scan_start) 1314 return -ENOTSUPP; 1315 1316 for (i = 0; i < NUM_NL80211_BANDS; i++) { 1317 if (local->hw.wiphy->bands[i]) { 1318 bands_used |= BIT(i); 1319 rate_masks[i] = (u32) -1; 1320 num_bands++; 1321 } 1322 } 1323 1324 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 1325 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 1326 1327 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL); 1328 if (!ie) { 1329 ret = -ENOMEM; 1330 goto out; 1331 } 1332 1333 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 1334 1335 ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz, 1336 &sched_scan_ies, req->ie, 1337 req->ie_len, bands_used, rate_masks, &chandef, 1338 flags); 1339 1340 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies); 1341 if (ret == 0) { 1342 rcu_assign_pointer(local->sched_scan_sdata, sdata); 1343 rcu_assign_pointer(local->sched_scan_req, req); 1344 } 1345 1346 kfree(ie); 1347 1348 out: 1349 if (ret) { 1350 /* Clean in case of failure after HW restart or upon resume. */ 1351 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1352 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1353 } 1354 1355 return ret; 1356 } 1357 1358 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1359 struct cfg80211_sched_scan_request *req) 1360 { 1361 struct ieee80211_local *local = sdata->local; 1362 int ret; 1363 1364 mutex_lock(&local->mtx); 1365 1366 if (rcu_access_pointer(local->sched_scan_sdata)) { 1367 mutex_unlock(&local->mtx); 1368 return -EBUSY; 1369 } 1370 1371 ret = __ieee80211_request_sched_scan_start(sdata, req); 1372 1373 mutex_unlock(&local->mtx); 1374 return ret; 1375 } 1376 1377 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local) 1378 { 1379 struct ieee80211_sub_if_data *sched_scan_sdata; 1380 int ret = -ENOENT; 1381 1382 mutex_lock(&local->mtx); 1383 1384 if (!local->ops->sched_scan_stop) { 1385 ret = -ENOTSUPP; 1386 goto out; 1387 } 1388 1389 /* We don't want to restart sched scan anymore. */ 1390 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1391 1392 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata, 1393 lockdep_is_held(&local->mtx)); 1394 if (sched_scan_sdata) { 1395 ret = drv_sched_scan_stop(local, sched_scan_sdata); 1396 if (!ret) 1397 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1398 } 1399 out: 1400 mutex_unlock(&local->mtx); 1401 1402 return ret; 1403 } 1404 1405 void ieee80211_sched_scan_results(struct ieee80211_hw *hw) 1406 { 1407 struct ieee80211_local *local = hw_to_local(hw); 1408 1409 trace_api_sched_scan_results(local); 1410 1411 cfg80211_sched_scan_results(hw->wiphy, 0); 1412 } 1413 EXPORT_SYMBOL(ieee80211_sched_scan_results); 1414 1415 void ieee80211_sched_scan_end(struct ieee80211_local *local) 1416 { 1417 mutex_lock(&local->mtx); 1418 1419 if (!rcu_access_pointer(local->sched_scan_sdata)) { 1420 mutex_unlock(&local->mtx); 1421 return; 1422 } 1423 1424 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1425 1426 /* If sched scan was aborted by the driver. */ 1427 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1428 1429 mutex_unlock(&local->mtx); 1430 1431 cfg80211_sched_scan_stopped_locked(local->hw.wiphy, 0); 1432 } 1433 1434 void ieee80211_sched_scan_stopped_work(struct wiphy *wiphy, 1435 struct wiphy_work *work) 1436 { 1437 struct ieee80211_local *local = 1438 container_of(work, struct ieee80211_local, 1439 sched_scan_stopped_work); 1440 1441 ieee80211_sched_scan_end(local); 1442 } 1443 1444 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw) 1445 { 1446 struct ieee80211_local *local = hw_to_local(hw); 1447 1448 trace_api_sched_scan_stopped(local); 1449 1450 /* 1451 * this shouldn't really happen, so for simplicity 1452 * simply ignore it, and let mac80211 reconfigure 1453 * the sched scan later on. 1454 */ 1455 if (local->in_reconfig) 1456 return; 1457 1458 wiphy_work_queue(hw->wiphy, &local->sched_scan_stopped_work); 1459 } 1460 EXPORT_SYMBOL(ieee80211_sched_scan_stopped); 1461