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) 2018-2021 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 static void 59 ieee80211_update_bss_from_elems(struct ieee80211_local *local, 60 struct ieee80211_bss *bss, 61 struct ieee802_11_elems *elems, 62 struct ieee80211_rx_status *rx_status, 63 bool beacon) 64 { 65 int clen, srlen; 66 67 if (beacon) 68 bss->device_ts_beacon = rx_status->device_timestamp; 69 else 70 bss->device_ts_presp = rx_status->device_timestamp; 71 72 if (elems->parse_error) { 73 if (beacon) 74 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON; 75 else 76 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP; 77 } else { 78 if (beacon) 79 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON; 80 else 81 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP; 82 } 83 84 /* save the ERP value so that it is available at association time */ 85 if (elems->erp_info && (!elems->parse_error || 86 !(bss->valid_data & IEEE80211_BSS_VALID_ERP))) { 87 bss->erp_value = elems->erp_info[0]; 88 bss->has_erp_value = true; 89 if (!elems->parse_error) 90 bss->valid_data |= IEEE80211_BSS_VALID_ERP; 91 } 92 93 /* replace old supported rates if we get new values */ 94 if (!elems->parse_error || 95 !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) { 96 srlen = 0; 97 if (elems->supp_rates) { 98 clen = IEEE80211_MAX_SUPP_RATES; 99 if (clen > elems->supp_rates_len) 100 clen = elems->supp_rates_len; 101 memcpy(bss->supp_rates, elems->supp_rates, clen); 102 srlen += clen; 103 } 104 if (elems->ext_supp_rates) { 105 clen = IEEE80211_MAX_SUPP_RATES - srlen; 106 if (clen > elems->ext_supp_rates_len) 107 clen = elems->ext_supp_rates_len; 108 memcpy(bss->supp_rates + srlen, elems->ext_supp_rates, 109 clen); 110 srlen += clen; 111 } 112 if (srlen) { 113 bss->supp_rates_len = srlen; 114 if (!elems->parse_error) 115 bss->valid_data |= IEEE80211_BSS_VALID_RATES; 116 } 117 } 118 119 if (!elems->parse_error || 120 !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) { 121 bss->wmm_used = elems->wmm_param || elems->wmm_info; 122 bss->uapsd_supported = is_uapsd_supported(elems); 123 if (!elems->parse_error) 124 bss->valid_data |= IEEE80211_BSS_VALID_WMM; 125 } 126 127 if (beacon) { 128 struct ieee80211_supported_band *sband = 129 local->hw.wiphy->bands[rx_status->band]; 130 if (!(rx_status->encoding == RX_ENC_HT) && 131 !(rx_status->encoding == RX_ENC_VHT)) 132 bss->beacon_rate = 133 &sband->bitrates[rx_status->rate_idx]; 134 } 135 136 if (elems->vht_cap_elem) 137 bss->vht_cap_info = 138 le32_to_cpu(elems->vht_cap_elem->vht_cap_info); 139 else 140 bss->vht_cap_info = 0; 141 } 142 143 struct ieee80211_bss * 144 ieee80211_bss_info_update(struct ieee80211_local *local, 145 struct ieee80211_rx_status *rx_status, 146 struct ieee80211_mgmt *mgmt, size_t len, 147 struct ieee80211_channel *channel) 148 { 149 bool beacon = ieee80211_is_beacon(mgmt->frame_control) || 150 ieee80211_is_s1g_beacon(mgmt->frame_control); 151 struct cfg80211_bss *cbss, *non_tx_cbss; 152 struct ieee80211_bss *bss, *non_tx_bss; 153 struct cfg80211_inform_bss bss_meta = { 154 .boottime_ns = rx_status->boottime_ns, 155 }; 156 bool signal_valid; 157 struct ieee80211_sub_if_data *scan_sdata; 158 struct ieee802_11_elems *elems; 159 size_t baselen; 160 u8 *elements; 161 162 if (rx_status->flag & RX_FLAG_NO_SIGNAL_VAL) 163 bss_meta.signal = 0; /* invalid signal indication */ 164 else if (ieee80211_hw_check(&local->hw, SIGNAL_DBM)) 165 bss_meta.signal = rx_status->signal * 100; 166 else if (ieee80211_hw_check(&local->hw, SIGNAL_UNSPEC)) 167 bss_meta.signal = (rx_status->signal * 100) / local->hw.max_signal; 168 169 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_20; 170 if (rx_status->bw == RATE_INFO_BW_5) 171 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_5; 172 else if (rx_status->bw == RATE_INFO_BW_10) 173 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_10; 174 175 bss_meta.chan = channel; 176 177 rcu_read_lock(); 178 scan_sdata = rcu_dereference(local->scan_sdata); 179 if (scan_sdata && scan_sdata->vif.type == NL80211_IFTYPE_STATION && 180 scan_sdata->vif.cfg.assoc && 181 ieee80211_have_rx_timestamp(rx_status)) { 182 bss_meta.parent_tsf = 183 ieee80211_calculate_rx_timestamp(local, rx_status, 184 len + FCS_LEN, 24); 185 ether_addr_copy(bss_meta.parent_bssid, 186 scan_sdata->vif.bss_conf.bssid); 187 } 188 rcu_read_unlock(); 189 190 cbss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, 191 mgmt, len, GFP_ATOMIC); 192 if (!cbss) 193 return NULL; 194 195 if (ieee80211_is_probe_resp(mgmt->frame_control)) { 196 elements = mgmt->u.probe_resp.variable; 197 baselen = offsetof(struct ieee80211_mgmt, 198 u.probe_resp.variable); 199 } else if (ieee80211_is_s1g_beacon(mgmt->frame_control)) { 200 struct ieee80211_ext *ext = (void *) mgmt; 201 202 baselen = offsetof(struct ieee80211_ext, u.s1g_beacon.variable); 203 elements = ext->u.s1g_beacon.variable; 204 } else { 205 baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable); 206 elements = mgmt->u.beacon.variable; 207 } 208 209 if (baselen > len) 210 return NULL; 211 212 elems = ieee802_11_parse_elems(elements, len - baselen, false, cbss); 213 if (!elems) 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 bss = (void *)cbss->priv; 222 ieee80211_update_bss_from_elems(local, bss, elems, rx_status, beacon); 223 kfree(elems); 224 225 list_for_each_entry(non_tx_cbss, &cbss->nontrans_list, nontrans_list) { 226 non_tx_bss = (void *)non_tx_cbss->priv; 227 228 elems = ieee802_11_parse_elems(elements, len - baselen, false, 229 non_tx_cbss); 230 if (!elems) 231 continue; 232 233 ieee80211_update_bss_from_elems(local, non_tx_bss, elems, 234 rx_status, beacon); 235 kfree(elems); 236 } 237 238 return bss; 239 } 240 241 static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata, 242 u32 scan_flags, const u8 *da) 243 { 244 if (!sdata) 245 return false; 246 /* accept broadcast for OCE */ 247 if (scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP && 248 is_broadcast_ether_addr(da)) 249 return true; 250 if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 251 return true; 252 return ether_addr_equal(da, sdata->vif.addr); 253 } 254 255 void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb) 256 { 257 struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); 258 struct ieee80211_sub_if_data *sdata1, *sdata2; 259 struct ieee80211_mgmt *mgmt = (void *)skb->data; 260 struct ieee80211_bss *bss; 261 struct ieee80211_channel *channel; 262 size_t min_hdr_len = offsetof(struct ieee80211_mgmt, 263 u.probe_resp.variable); 264 265 if (!ieee80211_is_probe_resp(mgmt->frame_control) && 266 !ieee80211_is_beacon(mgmt->frame_control) && 267 !ieee80211_is_s1g_beacon(mgmt->frame_control)) 268 return; 269 270 if (ieee80211_is_s1g_beacon(mgmt->frame_control)) { 271 if (ieee80211_is_s1g_short_beacon(mgmt->frame_control)) 272 min_hdr_len = offsetof(struct ieee80211_ext, 273 u.s1g_short_beacon.variable); 274 else 275 min_hdr_len = offsetof(struct ieee80211_ext, 276 u.s1g_beacon); 277 } 278 279 if (skb->len < min_hdr_len) 280 return; 281 282 sdata1 = rcu_dereference(local->scan_sdata); 283 sdata2 = rcu_dereference(local->sched_scan_sdata); 284 285 if (likely(!sdata1 && !sdata2)) 286 return; 287 288 if (test_and_clear_bit(SCAN_BEACON_WAIT, &local->scanning)) { 289 /* 290 * we were passive scanning because of radar/no-IR, but 291 * the beacon/proberesp rx gives us an opportunity to upgrade 292 * to active scan 293 */ 294 set_bit(SCAN_BEACON_DONE, &local->scanning); 295 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0); 296 } 297 298 if (ieee80211_is_probe_resp(mgmt->frame_control)) { 299 struct cfg80211_scan_request *scan_req; 300 struct cfg80211_sched_scan_request *sched_scan_req; 301 u32 scan_req_flags = 0, sched_scan_req_flags = 0; 302 303 scan_req = rcu_dereference(local->scan_req); 304 sched_scan_req = rcu_dereference(local->sched_scan_req); 305 306 if (scan_req) 307 scan_req_flags = scan_req->flags; 308 309 if (sched_scan_req) 310 sched_scan_req_flags = sched_scan_req->flags; 311 312 /* ignore ProbeResp to foreign address or non-bcast (OCE) 313 * unless scanning with randomised address 314 */ 315 if (!ieee80211_scan_accept_presp(sdata1, scan_req_flags, 316 mgmt->da) && 317 !ieee80211_scan_accept_presp(sdata2, sched_scan_req_flags, 318 mgmt->da)) 319 return; 320 } 321 322 channel = ieee80211_get_channel_khz(local->hw.wiphy, 323 ieee80211_rx_status_to_khz(rx_status)); 324 325 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 326 return; 327 328 bss = ieee80211_bss_info_update(local, rx_status, 329 mgmt, skb->len, 330 channel); 331 if (bss) 332 ieee80211_rx_bss_put(local, bss); 333 } 334 335 static void 336 ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef, 337 enum nl80211_bss_scan_width scan_width) 338 { 339 memset(chandef, 0, sizeof(*chandef)); 340 switch (scan_width) { 341 case NL80211_BSS_CHAN_WIDTH_5: 342 chandef->width = NL80211_CHAN_WIDTH_5; 343 break; 344 case NL80211_BSS_CHAN_WIDTH_10: 345 chandef->width = NL80211_CHAN_WIDTH_10; 346 break; 347 default: 348 chandef->width = NL80211_CHAN_WIDTH_20_NOHT; 349 break; 350 } 351 } 352 353 /* return false if no more work */ 354 static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data *sdata) 355 { 356 struct ieee80211_local *local = sdata->local; 357 struct cfg80211_scan_request *req; 358 struct cfg80211_chan_def chandef; 359 u8 bands_used = 0; 360 int i, ielen, n_chans; 361 u32 flags = 0; 362 363 req = rcu_dereference_protected(local->scan_req, 364 lockdep_is_held(&local->mtx)); 365 366 if (test_bit(SCAN_HW_CANCELLED, &local->scanning)) 367 return false; 368 369 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 370 for (i = 0; i < req->n_channels; i++) { 371 local->hw_scan_req->req.channels[i] = req->channels[i]; 372 bands_used |= BIT(req->channels[i]->band); 373 } 374 375 n_chans = req->n_channels; 376 } else { 377 do { 378 if (local->hw_scan_band == NUM_NL80211_BANDS) 379 return false; 380 381 n_chans = 0; 382 383 for (i = 0; i < req->n_channels; i++) { 384 if (req->channels[i]->band != 385 local->hw_scan_band) 386 continue; 387 local->hw_scan_req->req.channels[n_chans] = 388 req->channels[i]; 389 n_chans++; 390 bands_used |= BIT(req->channels[i]->band); 391 } 392 393 local->hw_scan_band++; 394 } while (!n_chans); 395 } 396 397 local->hw_scan_req->req.n_channels = n_chans; 398 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 399 400 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 401 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 402 403 ielen = ieee80211_build_preq_ies(sdata, 404 (u8 *)local->hw_scan_req->req.ie, 405 local->hw_scan_ies_bufsize, 406 &local->hw_scan_req->ies, 407 req->ie, req->ie_len, 408 bands_used, req->rates, &chandef, 409 flags); 410 local->hw_scan_req->req.ie_len = ielen; 411 local->hw_scan_req->req.no_cck = req->no_cck; 412 ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr); 413 ether_addr_copy(local->hw_scan_req->req.mac_addr_mask, 414 req->mac_addr_mask); 415 ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid); 416 417 return true; 418 } 419 420 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) 421 { 422 struct ieee80211_local *local = hw_to_local(hw); 423 bool hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); 424 bool was_scanning = local->scanning; 425 struct cfg80211_scan_request *scan_req; 426 struct ieee80211_sub_if_data *scan_sdata; 427 struct ieee80211_sub_if_data *sdata; 428 429 lockdep_assert_held(&local->mtx); 430 431 /* 432 * It's ok to abort a not-yet-running scan (that 433 * we have one at all will be verified by checking 434 * local->scan_req next), but not to complete it 435 * successfully. 436 */ 437 if (WARN_ON(!local->scanning && !aborted)) 438 aborted = true; 439 440 if (WARN_ON(!local->scan_req)) 441 return; 442 443 scan_sdata = rcu_dereference_protected(local->scan_sdata, 444 lockdep_is_held(&local->mtx)); 445 446 if (hw_scan && !aborted && 447 !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) && 448 ieee80211_prep_hw_scan(scan_sdata)) { 449 int rc; 450 451 rc = drv_hw_scan(local, 452 rcu_dereference_protected(local->scan_sdata, 453 lockdep_is_held(&local->mtx)), 454 local->hw_scan_req); 455 456 if (rc == 0) 457 return; 458 459 /* HW scan failed and is going to be reported as aborted, 460 * so clear old scan info. 461 */ 462 memset(&local->scan_info, 0, sizeof(local->scan_info)); 463 aborted = true; 464 } 465 466 kfree(local->hw_scan_req); 467 local->hw_scan_req = NULL; 468 469 scan_req = rcu_dereference_protected(local->scan_req, 470 lockdep_is_held(&local->mtx)); 471 472 if (scan_req != local->int_scan_req) { 473 local->scan_info.aborted = aborted; 474 cfg80211_scan_done(scan_req, &local->scan_info); 475 } 476 RCU_INIT_POINTER(local->scan_req, NULL); 477 RCU_INIT_POINTER(local->scan_sdata, NULL); 478 479 local->scanning = 0; 480 local->scan_chandef.chan = NULL; 481 482 /* Set power back to normal operating levels. */ 483 ieee80211_hw_config(local, 0); 484 485 if (!hw_scan) { 486 ieee80211_configure_filter(local); 487 drv_sw_scan_complete(local, scan_sdata); 488 ieee80211_offchannel_return(local); 489 } 490 491 ieee80211_recalc_idle(local); 492 493 ieee80211_mlme_notify_scan_completed(local); 494 ieee80211_ibss_notify_scan_completed(local); 495 496 /* Requeue all the work that might have been ignored while 497 * the scan was in progress; if there was none this will 498 * just be a no-op for the particular interface. 499 */ 500 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 501 if (ieee80211_sdata_running(sdata)) 502 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 503 } 504 505 if (was_scanning) 506 ieee80211_start_next_roc(local); 507 } 508 509 void ieee80211_scan_completed(struct ieee80211_hw *hw, 510 struct cfg80211_scan_info *info) 511 { 512 struct ieee80211_local *local = hw_to_local(hw); 513 514 trace_api_scan_completed(local, info->aborted); 515 516 set_bit(SCAN_COMPLETED, &local->scanning); 517 if (info->aborted) 518 set_bit(SCAN_ABORTED, &local->scanning); 519 520 memcpy(&local->scan_info, info, sizeof(*info)); 521 522 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0); 523 } 524 EXPORT_SYMBOL(ieee80211_scan_completed); 525 526 static int ieee80211_start_sw_scan(struct ieee80211_local *local, 527 struct ieee80211_sub_if_data *sdata) 528 { 529 /* Software scan is not supported in multi-channel cases */ 530 if (local->use_chanctx) 531 return -EOPNOTSUPP; 532 533 /* 534 * Hardware/driver doesn't support hw_scan, so use software 535 * scanning instead. First send a nullfunc frame with power save 536 * bit on so that AP will buffer the frames for us while we are not 537 * listening, then send probe requests to each channel and wait for 538 * the responses. After all channels are scanned, tune back to the 539 * original channel and send a nullfunc frame with power save bit 540 * off to trigger the AP to send us all the buffered frames. 541 * 542 * Note that while local->sw_scanning is true everything else but 543 * nullfunc frames and probe requests will be dropped in 544 * ieee80211_tx_h_check_assoc(). 545 */ 546 drv_sw_scan_start(local, sdata, local->scan_addr); 547 548 local->leave_oper_channel_time = jiffies; 549 local->next_scan_state = SCAN_DECISION; 550 local->scan_channel_idx = 0; 551 552 ieee80211_offchannel_stop_vifs(local); 553 554 /* ensure nullfunc is transmitted before leaving operating channel */ 555 ieee80211_flush_queues(local, NULL, false); 556 557 ieee80211_configure_filter(local); 558 559 /* We need to set power level at maximum rate for scanning. */ 560 ieee80211_hw_config(local, 0); 561 562 ieee80211_queue_delayed_work(&local->hw, 563 &local->scan_work, 0); 564 565 return 0; 566 } 567 568 static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata) 569 { 570 struct ieee80211_local *local = sdata->local; 571 struct ieee80211_sub_if_data *sdata_iter; 572 573 if (!ieee80211_is_radar_required(local)) 574 return true; 575 576 if (!regulatory_pre_cac_allowed(local->hw.wiphy)) 577 return false; 578 579 mutex_lock(&local->iflist_mtx); 580 list_for_each_entry(sdata_iter, &local->interfaces, list) { 581 if (sdata_iter->wdev.cac_started) { 582 mutex_unlock(&local->iflist_mtx); 583 return false; 584 } 585 } 586 mutex_unlock(&local->iflist_mtx); 587 588 return true; 589 } 590 591 static bool ieee80211_can_scan(struct ieee80211_local *local, 592 struct ieee80211_sub_if_data *sdata) 593 { 594 if (!__ieee80211_can_leave_ch(sdata)) 595 return false; 596 597 if (!list_empty(&local->roc_list)) 598 return false; 599 600 if (sdata->vif.type == NL80211_IFTYPE_STATION && 601 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL) 602 return false; 603 604 return true; 605 } 606 607 void ieee80211_run_deferred_scan(struct ieee80211_local *local) 608 { 609 lockdep_assert_held(&local->mtx); 610 611 if (!local->scan_req || local->scanning) 612 return; 613 614 if (!ieee80211_can_scan(local, 615 rcu_dereference_protected( 616 local->scan_sdata, 617 lockdep_is_held(&local->mtx)))) 618 return; 619 620 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 621 round_jiffies_relative(0)); 622 } 623 624 static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata, 625 const u8 *src, const u8 *dst, 626 const u8 *ssid, size_t ssid_len, 627 const u8 *ie, size_t ie_len, 628 u32 ratemask, u32 flags, u32 tx_flags, 629 struct ieee80211_channel *channel) 630 { 631 struct sk_buff *skb; 632 633 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel, 634 ssid, ssid_len, 635 ie, ie_len, flags); 636 637 if (skb) { 638 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) { 639 struct ieee80211_hdr *hdr = (void *)skb->data; 640 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 641 u16 sn = get_random_u32(); 642 643 info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO; 644 hdr->seq_ctrl = 645 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn)); 646 } 647 IEEE80211_SKB_CB(skb)->flags |= tx_flags; 648 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band); 649 } 650 } 651 652 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, 653 unsigned long *next_delay) 654 { 655 int i; 656 struct ieee80211_sub_if_data *sdata; 657 struct cfg80211_scan_request *scan_req; 658 enum nl80211_band band = local->hw.conf.chandef.chan->band; 659 u32 flags = 0, tx_flags; 660 661 scan_req = rcu_dereference_protected(local->scan_req, 662 lockdep_is_held(&local->mtx)); 663 664 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK; 665 if (scan_req->no_cck) 666 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE; 667 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 668 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 669 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN) 670 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN; 671 672 sdata = rcu_dereference_protected(local->scan_sdata, 673 lockdep_is_held(&local->mtx)); 674 675 for (i = 0; i < scan_req->n_ssids; i++) 676 ieee80211_send_scan_probe_req( 677 sdata, local->scan_addr, scan_req->bssid, 678 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len, 679 scan_req->ie, scan_req->ie_len, 680 scan_req->rates[band], flags, 681 tx_flags, local->hw.conf.chandef.chan); 682 683 /* 684 * After sending probe requests, wait for probe responses 685 * on the channel. 686 */ 687 *next_delay = IEEE80211_CHANNEL_TIME; 688 local->next_scan_state = SCAN_DECISION; 689 } 690 691 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, 692 struct cfg80211_scan_request *req) 693 { 694 struct ieee80211_local *local = sdata->local; 695 bool hw_scan = local->ops->hw_scan; 696 int rc; 697 698 lockdep_assert_held(&local->mtx); 699 700 if (local->scan_req) 701 return -EBUSY; 702 703 if (!__ieee80211_can_leave_ch(sdata)) 704 return -EBUSY; 705 706 if (!ieee80211_can_scan(local, sdata)) { 707 /* wait for the work to finish/time out */ 708 rcu_assign_pointer(local->scan_req, req); 709 rcu_assign_pointer(local->scan_sdata, sdata); 710 return 0; 711 } 712 713 again: 714 if (hw_scan) { 715 u8 *ies; 716 717 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len; 718 719 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 720 int i, n_bands = 0; 721 u8 bands_counted = 0; 722 723 for (i = 0; i < req->n_channels; i++) { 724 if (bands_counted & BIT(req->channels[i]->band)) 725 continue; 726 bands_counted |= BIT(req->channels[i]->band); 727 n_bands++; 728 } 729 730 local->hw_scan_ies_bufsize *= n_bands; 731 } 732 733 local->hw_scan_req = kmalloc( 734 sizeof(*local->hw_scan_req) + 735 req->n_channels * sizeof(req->channels[0]) + 736 local->hw_scan_ies_bufsize, GFP_KERNEL); 737 if (!local->hw_scan_req) 738 return -ENOMEM; 739 740 local->hw_scan_req->req.ssids = req->ssids; 741 local->hw_scan_req->req.n_ssids = req->n_ssids; 742 ies = (u8 *)local->hw_scan_req + 743 sizeof(*local->hw_scan_req) + 744 req->n_channels * sizeof(req->channels[0]); 745 local->hw_scan_req->req.ie = ies; 746 local->hw_scan_req->req.flags = req->flags; 747 eth_broadcast_addr(local->hw_scan_req->req.bssid); 748 local->hw_scan_req->req.duration = req->duration; 749 local->hw_scan_req->req.duration_mandatory = 750 req->duration_mandatory; 751 752 local->hw_scan_band = 0; 753 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params; 754 local->hw_scan_req->req.scan_6ghz_params = 755 req->scan_6ghz_params; 756 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz; 757 758 /* 759 * After allocating local->hw_scan_req, we must 760 * go through until ieee80211_prep_hw_scan(), so 761 * anything that might be changed here and leave 762 * this function early must not go after this 763 * allocation. 764 */ 765 } 766 767 rcu_assign_pointer(local->scan_req, req); 768 rcu_assign_pointer(local->scan_sdata, sdata); 769 770 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 771 get_random_mask_addr(local->scan_addr, 772 req->mac_addr, 773 req->mac_addr_mask); 774 else 775 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN); 776 777 if (hw_scan) { 778 __set_bit(SCAN_HW_SCANNING, &local->scanning); 779 } else if ((req->n_channels == 1) && 780 (req->channels[0] == local->_oper_chandef.chan)) { 781 /* 782 * If we are scanning only on the operating channel 783 * then we do not need to stop normal activities 784 */ 785 unsigned long next_delay; 786 787 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning); 788 789 ieee80211_recalc_idle(local); 790 791 /* Notify driver scan is starting, keep order of operations 792 * same as normal software scan, in case that matters. */ 793 drv_sw_scan_start(local, sdata, local->scan_addr); 794 795 ieee80211_configure_filter(local); /* accept probe-responses */ 796 797 /* We need to ensure power level is at max for scanning. */ 798 ieee80211_hw_config(local, 0); 799 800 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR | 801 IEEE80211_CHAN_RADAR)) || 802 !req->n_ssids) { 803 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 804 if (req->n_ssids) 805 set_bit(SCAN_BEACON_WAIT, &local->scanning); 806 } else { 807 ieee80211_scan_state_send_probe(local, &next_delay); 808 next_delay = IEEE80211_CHANNEL_TIME; 809 } 810 811 /* Now, just wait a bit and we are all done! */ 812 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 813 next_delay); 814 return 0; 815 } else { 816 /* Do normal software scan */ 817 __set_bit(SCAN_SW_SCANNING, &local->scanning); 818 } 819 820 ieee80211_recalc_idle(local); 821 822 if (hw_scan) { 823 WARN_ON(!ieee80211_prep_hw_scan(sdata)); 824 rc = drv_hw_scan(local, sdata, local->hw_scan_req); 825 } else { 826 rc = ieee80211_start_sw_scan(local, sdata); 827 } 828 829 if (rc) { 830 kfree(local->hw_scan_req); 831 local->hw_scan_req = NULL; 832 local->scanning = 0; 833 834 ieee80211_recalc_idle(local); 835 836 local->scan_req = NULL; 837 RCU_INIT_POINTER(local->scan_sdata, NULL); 838 } 839 840 if (hw_scan && rc == 1) { 841 /* 842 * we can't fall back to software for P2P-GO 843 * as it must update NoA etc. 844 */ 845 if (ieee80211_vif_type_p2p(&sdata->vif) == 846 NL80211_IFTYPE_P2P_GO) 847 return -EOPNOTSUPP; 848 hw_scan = false; 849 goto again; 850 } 851 852 return rc; 853 } 854 855 static unsigned long 856 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) 857 { 858 /* 859 * TODO: channel switching also consumes quite some time, 860 * add that delay as well to get a better estimation 861 */ 862 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) 863 return IEEE80211_PASSIVE_CHANNEL_TIME; 864 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; 865 } 866 867 static void ieee80211_scan_state_decision(struct ieee80211_local *local, 868 unsigned long *next_delay) 869 { 870 bool associated = false; 871 bool tx_empty = true; 872 bool bad_latency; 873 struct ieee80211_sub_if_data *sdata; 874 struct ieee80211_channel *next_chan; 875 enum mac80211_scan_state next_scan_state; 876 struct cfg80211_scan_request *scan_req; 877 878 /* 879 * check if at least one STA interface is associated, 880 * check if at least one STA interface has pending tx frames 881 * and grab the lowest used beacon interval 882 */ 883 mutex_lock(&local->iflist_mtx); 884 list_for_each_entry(sdata, &local->interfaces, list) { 885 if (!ieee80211_sdata_running(sdata)) 886 continue; 887 888 if (sdata->vif.type == NL80211_IFTYPE_STATION) { 889 if (sdata->u.mgd.associated) { 890 associated = true; 891 892 if (!qdisc_all_tx_empty(sdata->dev)) { 893 tx_empty = false; 894 break; 895 } 896 } 897 } 898 } 899 mutex_unlock(&local->iflist_mtx); 900 901 scan_req = rcu_dereference_protected(local->scan_req, 902 lockdep_is_held(&local->mtx)); 903 904 next_chan = scan_req->channels[local->scan_channel_idx]; 905 906 /* 907 * we're currently scanning a different channel, let's 908 * see if we can scan another channel without interfering 909 * with the current traffic situation. 910 * 911 * Keep good latency, do not stay off-channel more than 125 ms. 912 */ 913 914 bad_latency = time_after(jiffies + 915 ieee80211_scan_get_channel_time(next_chan), 916 local->leave_oper_channel_time + HZ / 8); 917 918 if (associated && !tx_empty) { 919 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY) 920 next_scan_state = SCAN_ABORT; 921 else 922 next_scan_state = SCAN_SUSPEND; 923 } else if (associated && bad_latency) { 924 next_scan_state = SCAN_SUSPEND; 925 } else { 926 next_scan_state = SCAN_SET_CHANNEL; 927 } 928 929 local->next_scan_state = next_scan_state; 930 931 *next_delay = 0; 932 } 933 934 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, 935 unsigned long *next_delay) 936 { 937 int skip; 938 struct ieee80211_channel *chan; 939 enum nl80211_bss_scan_width oper_scan_width; 940 struct cfg80211_scan_request *scan_req; 941 942 scan_req = rcu_dereference_protected(local->scan_req, 943 lockdep_is_held(&local->mtx)); 944 945 skip = 0; 946 chan = scan_req->channels[local->scan_channel_idx]; 947 948 local->scan_chandef.chan = chan; 949 local->scan_chandef.center_freq1 = chan->center_freq; 950 local->scan_chandef.freq1_offset = chan->freq_offset; 951 local->scan_chandef.center_freq2 = 0; 952 953 /* For scanning on the S1G band, ignore scan_width (which is constant 954 * across all channels) for now since channel width is specific to each 955 * channel. Detect the required channel width here and likely revisit 956 * later. Maybe scan_width could be used to build the channel scan list? 957 */ 958 if (chan->band == NL80211_BAND_S1GHZ) { 959 local->scan_chandef.width = ieee80211_s1g_channel_width(chan); 960 goto set_channel; 961 } 962 963 switch (scan_req->scan_width) { 964 case NL80211_BSS_CHAN_WIDTH_5: 965 local->scan_chandef.width = NL80211_CHAN_WIDTH_5; 966 break; 967 case NL80211_BSS_CHAN_WIDTH_10: 968 local->scan_chandef.width = NL80211_CHAN_WIDTH_10; 969 break; 970 default: 971 case NL80211_BSS_CHAN_WIDTH_20: 972 /* If scanning on oper channel, use whatever channel-type 973 * is currently in use. 974 */ 975 oper_scan_width = cfg80211_chandef_to_scan_width( 976 &local->_oper_chandef); 977 if (chan == local->_oper_chandef.chan && 978 oper_scan_width == scan_req->scan_width) 979 local->scan_chandef = local->_oper_chandef; 980 else 981 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT; 982 break; 983 case NL80211_BSS_CHAN_WIDTH_1: 984 case NL80211_BSS_CHAN_WIDTH_2: 985 /* shouldn't get here, S1G handled above */ 986 WARN_ON(1); 987 break; 988 } 989 990 set_channel: 991 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) 992 skip = 1; 993 994 /* advance state machine to next channel/band */ 995 local->scan_channel_idx++; 996 997 if (skip) { 998 /* if we skip this channel return to the decision state */ 999 local->next_scan_state = SCAN_DECISION; 1000 return; 1001 } 1002 1003 /* 1004 * Probe delay is used to update the NAV, cf. 11.1.3.2.2 1005 * (which unfortunately doesn't say _why_ step a) is done, 1006 * but it waits for the probe delay or until a frame is 1007 * received - and the received frame would update the NAV). 1008 * For now, we do not support waiting until a frame is 1009 * received. 1010 * 1011 * In any case, it is not necessary for a passive scan. 1012 */ 1013 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) || 1014 !scan_req->n_ssids) { 1015 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 1016 local->next_scan_state = SCAN_DECISION; 1017 if (scan_req->n_ssids) 1018 set_bit(SCAN_BEACON_WAIT, &local->scanning); 1019 return; 1020 } 1021 1022 /* active scan, send probes */ 1023 *next_delay = IEEE80211_PROBE_DELAY; 1024 local->next_scan_state = SCAN_SEND_PROBE; 1025 } 1026 1027 static void ieee80211_scan_state_suspend(struct ieee80211_local *local, 1028 unsigned long *next_delay) 1029 { 1030 /* switch back to the operating channel */ 1031 local->scan_chandef.chan = NULL; 1032 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 1033 1034 /* disable PS */ 1035 ieee80211_offchannel_return(local); 1036 1037 *next_delay = HZ / 5; 1038 /* afterwards, resume scan & go to next channel */ 1039 local->next_scan_state = SCAN_RESUME; 1040 } 1041 1042 static void ieee80211_scan_state_resume(struct ieee80211_local *local, 1043 unsigned long *next_delay) 1044 { 1045 ieee80211_offchannel_stop_vifs(local); 1046 1047 if (local->ops->flush) { 1048 ieee80211_flush_queues(local, NULL, false); 1049 *next_delay = 0; 1050 } else 1051 *next_delay = HZ / 10; 1052 1053 /* remember when we left the operating channel */ 1054 local->leave_oper_channel_time = jiffies; 1055 1056 /* advance to the next channel to be scanned */ 1057 local->next_scan_state = SCAN_SET_CHANNEL; 1058 } 1059 1060 void ieee80211_scan_work(struct work_struct *work) 1061 { 1062 struct ieee80211_local *local = 1063 container_of(work, struct ieee80211_local, scan_work.work); 1064 struct ieee80211_sub_if_data *sdata; 1065 struct cfg80211_scan_request *scan_req; 1066 unsigned long next_delay = 0; 1067 bool aborted; 1068 1069 mutex_lock(&local->mtx); 1070 1071 if (!ieee80211_can_run_worker(local)) { 1072 aborted = true; 1073 goto out_complete; 1074 } 1075 1076 sdata = rcu_dereference_protected(local->scan_sdata, 1077 lockdep_is_held(&local->mtx)); 1078 scan_req = rcu_dereference_protected(local->scan_req, 1079 lockdep_is_held(&local->mtx)); 1080 1081 /* When scanning on-channel, the first-callback means completed. */ 1082 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) { 1083 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1084 goto out_complete; 1085 } 1086 1087 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) { 1088 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1089 goto out_complete; 1090 } 1091 1092 if (!sdata || !scan_req) 1093 goto out; 1094 1095 if (!local->scanning) { 1096 int rc; 1097 1098 RCU_INIT_POINTER(local->scan_req, NULL); 1099 RCU_INIT_POINTER(local->scan_sdata, NULL); 1100 1101 rc = __ieee80211_start_scan(sdata, scan_req); 1102 if (rc) { 1103 /* need to complete scan in cfg80211 */ 1104 rcu_assign_pointer(local->scan_req, scan_req); 1105 aborted = true; 1106 goto out_complete; 1107 } else 1108 goto out; 1109 } 1110 1111 clear_bit(SCAN_BEACON_WAIT, &local->scanning); 1112 1113 /* 1114 * as long as no delay is required advance immediately 1115 * without scheduling a new work 1116 */ 1117 do { 1118 if (!ieee80211_sdata_running(sdata)) { 1119 aborted = true; 1120 goto out_complete; 1121 } 1122 1123 if (test_and_clear_bit(SCAN_BEACON_DONE, &local->scanning) && 1124 local->next_scan_state == SCAN_DECISION) 1125 local->next_scan_state = SCAN_SEND_PROBE; 1126 1127 switch (local->next_scan_state) { 1128 case SCAN_DECISION: 1129 /* if no more bands/channels left, complete scan */ 1130 if (local->scan_channel_idx >= scan_req->n_channels) { 1131 aborted = false; 1132 goto out_complete; 1133 } 1134 ieee80211_scan_state_decision(local, &next_delay); 1135 break; 1136 case SCAN_SET_CHANNEL: 1137 ieee80211_scan_state_set_channel(local, &next_delay); 1138 break; 1139 case SCAN_SEND_PROBE: 1140 ieee80211_scan_state_send_probe(local, &next_delay); 1141 break; 1142 case SCAN_SUSPEND: 1143 ieee80211_scan_state_suspend(local, &next_delay); 1144 break; 1145 case SCAN_RESUME: 1146 ieee80211_scan_state_resume(local, &next_delay); 1147 break; 1148 case SCAN_ABORT: 1149 aborted = true; 1150 goto out_complete; 1151 } 1152 } while (next_delay == 0); 1153 1154 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 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 /* 1247 * Only call this function when a scan can't be queued -- under RTNL. 1248 */ 1249 void ieee80211_scan_cancel(struct ieee80211_local *local) 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 /* 1298 * If the work is currently running, it must be blocked on 1299 * the mutex, but we'll set scan_sdata = NULL and it'll 1300 * simply exit once it acquires the mutex. 1301 */ 1302 cancel_delayed_work(&local->scan_work); 1303 /* and clean up */ 1304 memset(&local->scan_info, 0, sizeof(local->scan_info)); 1305 __ieee80211_scan_completed(&local->hw, true); 1306 out: 1307 mutex_unlock(&local->mtx); 1308 } 1309 1310 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1311 struct cfg80211_sched_scan_request *req) 1312 { 1313 struct ieee80211_local *local = sdata->local; 1314 struct ieee80211_scan_ies sched_scan_ies = {}; 1315 struct cfg80211_chan_def chandef; 1316 int ret, i, iebufsz, num_bands = 0; 1317 u32 rate_masks[NUM_NL80211_BANDS] = {}; 1318 u8 bands_used = 0; 1319 u8 *ie; 1320 u32 flags = 0; 1321 1322 iebufsz = local->scan_ies_len + req->ie_len; 1323 1324 lockdep_assert_held(&local->mtx); 1325 1326 if (!local->ops->sched_scan_start) 1327 return -ENOTSUPP; 1328 1329 for (i = 0; i < NUM_NL80211_BANDS; i++) { 1330 if (local->hw.wiphy->bands[i]) { 1331 bands_used |= BIT(i); 1332 rate_masks[i] = (u32) -1; 1333 num_bands++; 1334 } 1335 } 1336 1337 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 1338 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 1339 1340 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL); 1341 if (!ie) { 1342 ret = -ENOMEM; 1343 goto out; 1344 } 1345 1346 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 1347 1348 ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz, 1349 &sched_scan_ies, req->ie, 1350 req->ie_len, bands_used, rate_masks, &chandef, 1351 flags); 1352 1353 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies); 1354 if (ret == 0) { 1355 rcu_assign_pointer(local->sched_scan_sdata, sdata); 1356 rcu_assign_pointer(local->sched_scan_req, req); 1357 } 1358 1359 kfree(ie); 1360 1361 out: 1362 if (ret) { 1363 /* Clean in case of failure after HW restart or upon resume. */ 1364 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1365 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1366 } 1367 1368 return ret; 1369 } 1370 1371 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1372 struct cfg80211_sched_scan_request *req) 1373 { 1374 struct ieee80211_local *local = sdata->local; 1375 int ret; 1376 1377 mutex_lock(&local->mtx); 1378 1379 if (rcu_access_pointer(local->sched_scan_sdata)) { 1380 mutex_unlock(&local->mtx); 1381 return -EBUSY; 1382 } 1383 1384 ret = __ieee80211_request_sched_scan_start(sdata, req); 1385 1386 mutex_unlock(&local->mtx); 1387 return ret; 1388 } 1389 1390 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local) 1391 { 1392 struct ieee80211_sub_if_data *sched_scan_sdata; 1393 int ret = -ENOENT; 1394 1395 mutex_lock(&local->mtx); 1396 1397 if (!local->ops->sched_scan_stop) { 1398 ret = -ENOTSUPP; 1399 goto out; 1400 } 1401 1402 /* We don't want to restart sched scan anymore. */ 1403 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1404 1405 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata, 1406 lockdep_is_held(&local->mtx)); 1407 if (sched_scan_sdata) { 1408 ret = drv_sched_scan_stop(local, sched_scan_sdata); 1409 if (!ret) 1410 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1411 } 1412 out: 1413 mutex_unlock(&local->mtx); 1414 1415 return ret; 1416 } 1417 1418 void ieee80211_sched_scan_results(struct ieee80211_hw *hw) 1419 { 1420 struct ieee80211_local *local = hw_to_local(hw); 1421 1422 trace_api_sched_scan_results(local); 1423 1424 cfg80211_sched_scan_results(hw->wiphy, 0); 1425 } 1426 EXPORT_SYMBOL(ieee80211_sched_scan_results); 1427 1428 void ieee80211_sched_scan_end(struct ieee80211_local *local) 1429 { 1430 mutex_lock(&local->mtx); 1431 1432 if (!rcu_access_pointer(local->sched_scan_sdata)) { 1433 mutex_unlock(&local->mtx); 1434 return; 1435 } 1436 1437 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1438 1439 /* If sched scan was aborted by the driver. */ 1440 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1441 1442 mutex_unlock(&local->mtx); 1443 1444 cfg80211_sched_scan_stopped(local->hw.wiphy, 0); 1445 } 1446 1447 void ieee80211_sched_scan_stopped_work(struct work_struct *work) 1448 { 1449 struct ieee80211_local *local = 1450 container_of(work, struct ieee80211_local, 1451 sched_scan_stopped_work); 1452 1453 ieee80211_sched_scan_end(local); 1454 } 1455 1456 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw) 1457 { 1458 struct ieee80211_local *local = hw_to_local(hw); 1459 1460 trace_api_sched_scan_stopped(local); 1461 1462 /* 1463 * this shouldn't really happen, so for simplicity 1464 * simply ignore it, and let mac80211 reconfigure 1465 * the sched scan later on. 1466 */ 1467 if (local->in_reconfig) 1468 return; 1469 1470 schedule_work(&local->sched_scan_stopped_work); 1471 } 1472 EXPORT_SYMBOL(ieee80211_sched_scan_stopped); 1473