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) 2018-2020 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.bss_conf.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 ieee802_11_parse_elems(elements, len - baselen, false, &elems, 213 mgmt->bssid, cbss->bssid); 214 215 /* In case the signal is invalid update the status */ 216 signal_valid = channel == cbss->channel; 217 if (!signal_valid) 218 rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL; 219 220 bss = (void *)cbss->priv; 221 ieee80211_update_bss_from_elems(local, bss, &elems, rx_status, beacon); 222 223 list_for_each_entry(non_tx_cbss, &cbss->nontrans_list, nontrans_list) { 224 non_tx_bss = (void *)non_tx_cbss->priv; 225 226 ieee80211_update_bss_from_elems(local, non_tx_bss, &elems, 227 rx_status, beacon); 228 } 229 230 return bss; 231 } 232 233 static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata, 234 u32 scan_flags, const u8 *da) 235 { 236 if (!sdata) 237 return false; 238 /* accept broadcast for OCE */ 239 if (scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP && 240 is_broadcast_ether_addr(da)) 241 return true; 242 if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 243 return true; 244 return ether_addr_equal(da, sdata->vif.addr); 245 } 246 247 void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb) 248 { 249 struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); 250 struct ieee80211_sub_if_data *sdata1, *sdata2; 251 struct ieee80211_mgmt *mgmt = (void *)skb->data; 252 struct ieee80211_bss *bss; 253 struct ieee80211_channel *channel; 254 size_t min_hdr_len = offsetof(struct ieee80211_mgmt, 255 u.probe_resp.variable); 256 257 if (!ieee80211_is_probe_resp(mgmt->frame_control) && 258 !ieee80211_is_beacon(mgmt->frame_control) && 259 !ieee80211_is_s1g_beacon(mgmt->frame_control)) 260 return; 261 262 if (ieee80211_is_s1g_beacon(mgmt->frame_control)) { 263 if (ieee80211_is_s1g_short_beacon(mgmt->frame_control)) 264 min_hdr_len = offsetof(struct ieee80211_ext, 265 u.s1g_short_beacon.variable); 266 else 267 min_hdr_len = offsetof(struct ieee80211_ext, 268 u.s1g_beacon); 269 } 270 271 if (skb->len < min_hdr_len) 272 return; 273 274 sdata1 = rcu_dereference(local->scan_sdata); 275 sdata2 = rcu_dereference(local->sched_scan_sdata); 276 277 if (likely(!sdata1 && !sdata2)) 278 return; 279 280 if (ieee80211_is_probe_resp(mgmt->frame_control)) { 281 struct cfg80211_scan_request *scan_req; 282 struct cfg80211_sched_scan_request *sched_scan_req; 283 u32 scan_req_flags = 0, sched_scan_req_flags = 0; 284 285 scan_req = rcu_dereference(local->scan_req); 286 sched_scan_req = rcu_dereference(local->sched_scan_req); 287 288 if (scan_req) 289 scan_req_flags = scan_req->flags; 290 291 if (sched_scan_req) 292 sched_scan_req_flags = sched_scan_req->flags; 293 294 /* ignore ProbeResp to foreign address or non-bcast (OCE) 295 * unless scanning with randomised address 296 */ 297 if (!ieee80211_scan_accept_presp(sdata1, scan_req_flags, 298 mgmt->da) && 299 !ieee80211_scan_accept_presp(sdata2, sched_scan_req_flags, 300 mgmt->da)) 301 return; 302 } 303 304 channel = ieee80211_get_channel_khz(local->hw.wiphy, 305 ieee80211_rx_status_to_khz(rx_status)); 306 307 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 308 return; 309 310 bss = ieee80211_bss_info_update(local, rx_status, 311 mgmt, skb->len, 312 channel); 313 if (bss) 314 ieee80211_rx_bss_put(local, bss); 315 } 316 317 static void 318 ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef, 319 enum nl80211_bss_scan_width scan_width) 320 { 321 memset(chandef, 0, sizeof(*chandef)); 322 switch (scan_width) { 323 case NL80211_BSS_CHAN_WIDTH_5: 324 chandef->width = NL80211_CHAN_WIDTH_5; 325 break; 326 case NL80211_BSS_CHAN_WIDTH_10: 327 chandef->width = NL80211_CHAN_WIDTH_10; 328 break; 329 default: 330 chandef->width = NL80211_CHAN_WIDTH_20_NOHT; 331 break; 332 } 333 } 334 335 /* return false if no more work */ 336 static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data *sdata) 337 { 338 struct ieee80211_local *local = sdata->local; 339 struct cfg80211_scan_request *req; 340 struct cfg80211_chan_def chandef; 341 u8 bands_used = 0; 342 int i, ielen, n_chans; 343 u32 flags = 0; 344 345 req = rcu_dereference_protected(local->scan_req, 346 lockdep_is_held(&local->mtx)); 347 348 if (test_bit(SCAN_HW_CANCELLED, &local->scanning)) 349 return false; 350 351 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 352 for (i = 0; i < req->n_channels; i++) { 353 local->hw_scan_req->req.channels[i] = req->channels[i]; 354 bands_used |= BIT(req->channels[i]->band); 355 } 356 357 n_chans = req->n_channels; 358 } else { 359 do { 360 if (local->hw_scan_band == NUM_NL80211_BANDS) 361 return false; 362 363 n_chans = 0; 364 365 for (i = 0; i < req->n_channels; i++) { 366 if (req->channels[i]->band != 367 local->hw_scan_band) 368 continue; 369 local->hw_scan_req->req.channels[n_chans] = 370 req->channels[i]; 371 n_chans++; 372 bands_used |= BIT(req->channels[i]->band); 373 } 374 375 local->hw_scan_band++; 376 } while (!n_chans); 377 } 378 379 local->hw_scan_req->req.n_channels = n_chans; 380 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 381 382 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 383 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 384 385 ielen = ieee80211_build_preq_ies(sdata, 386 (u8 *)local->hw_scan_req->req.ie, 387 local->hw_scan_ies_bufsize, 388 &local->hw_scan_req->ies, 389 req->ie, req->ie_len, 390 bands_used, req->rates, &chandef, 391 flags); 392 local->hw_scan_req->req.ie_len = ielen; 393 local->hw_scan_req->req.no_cck = req->no_cck; 394 ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr); 395 ether_addr_copy(local->hw_scan_req->req.mac_addr_mask, 396 req->mac_addr_mask); 397 ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid); 398 399 return true; 400 } 401 402 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) 403 { 404 struct ieee80211_local *local = hw_to_local(hw); 405 bool hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); 406 bool was_scanning = local->scanning; 407 struct cfg80211_scan_request *scan_req; 408 struct ieee80211_sub_if_data *scan_sdata; 409 struct ieee80211_sub_if_data *sdata; 410 411 lockdep_assert_held(&local->mtx); 412 413 /* 414 * It's ok to abort a not-yet-running scan (that 415 * we have one at all will be verified by checking 416 * local->scan_req next), but not to complete it 417 * successfully. 418 */ 419 if (WARN_ON(!local->scanning && !aborted)) 420 aborted = true; 421 422 if (WARN_ON(!local->scan_req)) 423 return; 424 425 scan_sdata = rcu_dereference_protected(local->scan_sdata, 426 lockdep_is_held(&local->mtx)); 427 428 if (hw_scan && !aborted && 429 !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) && 430 ieee80211_prep_hw_scan(scan_sdata)) { 431 int rc; 432 433 rc = drv_hw_scan(local, 434 rcu_dereference_protected(local->scan_sdata, 435 lockdep_is_held(&local->mtx)), 436 local->hw_scan_req); 437 438 if (rc == 0) 439 return; 440 441 /* HW scan failed and is going to be reported as aborted, 442 * so clear old scan info. 443 */ 444 memset(&local->scan_info, 0, sizeof(local->scan_info)); 445 aborted = true; 446 } 447 448 kfree(local->hw_scan_req); 449 local->hw_scan_req = NULL; 450 451 scan_req = rcu_dereference_protected(local->scan_req, 452 lockdep_is_held(&local->mtx)); 453 454 if (scan_req != local->int_scan_req) { 455 local->scan_info.aborted = aborted; 456 cfg80211_scan_done(scan_req, &local->scan_info); 457 } 458 RCU_INIT_POINTER(local->scan_req, NULL); 459 RCU_INIT_POINTER(local->scan_sdata, NULL); 460 461 local->scanning = 0; 462 local->scan_chandef.chan = NULL; 463 464 /* Set power back to normal operating levels. */ 465 ieee80211_hw_config(local, 0); 466 467 if (!hw_scan) { 468 ieee80211_configure_filter(local); 469 drv_sw_scan_complete(local, scan_sdata); 470 ieee80211_offchannel_return(local); 471 } 472 473 ieee80211_recalc_idle(local); 474 475 ieee80211_mlme_notify_scan_completed(local); 476 ieee80211_ibss_notify_scan_completed(local); 477 478 /* Requeue all the work that might have been ignored while 479 * the scan was in progress; if there was none this will 480 * just be a no-op for the particular interface. 481 */ 482 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 483 if (ieee80211_sdata_running(sdata)) 484 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 485 } 486 487 if (was_scanning) 488 ieee80211_start_next_roc(local); 489 } 490 491 void ieee80211_scan_completed(struct ieee80211_hw *hw, 492 struct cfg80211_scan_info *info) 493 { 494 struct ieee80211_local *local = hw_to_local(hw); 495 496 trace_api_scan_completed(local, info->aborted); 497 498 set_bit(SCAN_COMPLETED, &local->scanning); 499 if (info->aborted) 500 set_bit(SCAN_ABORTED, &local->scanning); 501 502 memcpy(&local->scan_info, info, sizeof(*info)); 503 504 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0); 505 } 506 EXPORT_SYMBOL(ieee80211_scan_completed); 507 508 static int ieee80211_start_sw_scan(struct ieee80211_local *local, 509 struct ieee80211_sub_if_data *sdata) 510 { 511 /* Software scan is not supported in multi-channel cases */ 512 if (local->use_chanctx) 513 return -EOPNOTSUPP; 514 515 /* 516 * Hardware/driver doesn't support hw_scan, so use software 517 * scanning instead. First send a nullfunc frame with power save 518 * bit on so that AP will buffer the frames for us while we are not 519 * listening, then send probe requests to each channel and wait for 520 * the responses. After all channels are scanned, tune back to the 521 * original channel and send a nullfunc frame with power save bit 522 * off to trigger the AP to send us all the buffered frames. 523 * 524 * Note that while local->sw_scanning is true everything else but 525 * nullfunc frames and probe requests will be dropped in 526 * ieee80211_tx_h_check_assoc(). 527 */ 528 drv_sw_scan_start(local, sdata, local->scan_addr); 529 530 local->leave_oper_channel_time = jiffies; 531 local->next_scan_state = SCAN_DECISION; 532 local->scan_channel_idx = 0; 533 534 ieee80211_offchannel_stop_vifs(local); 535 536 /* ensure nullfunc is transmitted before leaving operating channel */ 537 ieee80211_flush_queues(local, NULL, false); 538 539 ieee80211_configure_filter(local); 540 541 /* We need to set power level at maximum rate for scanning. */ 542 ieee80211_hw_config(local, 0); 543 544 ieee80211_queue_delayed_work(&local->hw, 545 &local->scan_work, 0); 546 547 return 0; 548 } 549 550 static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata) 551 { 552 struct ieee80211_local *local = sdata->local; 553 struct ieee80211_sub_if_data *sdata_iter; 554 555 if (!ieee80211_is_radar_required(local)) 556 return true; 557 558 if (!regulatory_pre_cac_allowed(local->hw.wiphy)) 559 return false; 560 561 mutex_lock(&local->iflist_mtx); 562 list_for_each_entry(sdata_iter, &local->interfaces, list) { 563 if (sdata_iter->wdev.cac_started) { 564 mutex_unlock(&local->iflist_mtx); 565 return false; 566 } 567 } 568 mutex_unlock(&local->iflist_mtx); 569 570 return true; 571 } 572 573 static bool ieee80211_can_scan(struct ieee80211_local *local, 574 struct ieee80211_sub_if_data *sdata) 575 { 576 if (!__ieee80211_can_leave_ch(sdata)) 577 return false; 578 579 if (!list_empty(&local->roc_list)) 580 return false; 581 582 if (sdata->vif.type == NL80211_IFTYPE_STATION && 583 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL) 584 return false; 585 586 return true; 587 } 588 589 void ieee80211_run_deferred_scan(struct ieee80211_local *local) 590 { 591 lockdep_assert_held(&local->mtx); 592 593 if (!local->scan_req || local->scanning) 594 return; 595 596 if (!ieee80211_can_scan(local, 597 rcu_dereference_protected( 598 local->scan_sdata, 599 lockdep_is_held(&local->mtx)))) 600 return; 601 602 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 603 round_jiffies_relative(0)); 604 } 605 606 static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata, 607 const u8 *src, const u8 *dst, 608 const u8 *ssid, size_t ssid_len, 609 const u8 *ie, size_t ie_len, 610 u32 ratemask, u32 flags, u32 tx_flags, 611 struct ieee80211_channel *channel) 612 { 613 struct sk_buff *skb; 614 615 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel, 616 ssid, ssid_len, 617 ie, ie_len, flags); 618 619 if (skb) { 620 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) { 621 struct ieee80211_hdr *hdr = (void *)skb->data; 622 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 623 u16 sn = get_random_u32(); 624 625 info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO; 626 hdr->seq_ctrl = 627 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn)); 628 } 629 IEEE80211_SKB_CB(skb)->flags |= tx_flags; 630 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band); 631 } 632 } 633 634 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, 635 unsigned long *next_delay) 636 { 637 int i; 638 struct ieee80211_sub_if_data *sdata; 639 struct cfg80211_scan_request *scan_req; 640 enum nl80211_band band = local->hw.conf.chandef.chan->band; 641 u32 flags = 0, tx_flags; 642 643 scan_req = rcu_dereference_protected(local->scan_req, 644 lockdep_is_held(&local->mtx)); 645 646 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK; 647 if (scan_req->no_cck) 648 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE; 649 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 650 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 651 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN) 652 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN; 653 654 sdata = rcu_dereference_protected(local->scan_sdata, 655 lockdep_is_held(&local->mtx)); 656 657 for (i = 0; i < scan_req->n_ssids; i++) 658 ieee80211_send_scan_probe_req( 659 sdata, local->scan_addr, scan_req->bssid, 660 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len, 661 scan_req->ie, scan_req->ie_len, 662 scan_req->rates[band], flags, 663 tx_flags, local->hw.conf.chandef.chan); 664 665 /* 666 * After sending probe requests, wait for probe responses 667 * on the channel. 668 */ 669 *next_delay = IEEE80211_CHANNEL_TIME; 670 local->next_scan_state = SCAN_DECISION; 671 } 672 673 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, 674 struct cfg80211_scan_request *req) 675 { 676 struct ieee80211_local *local = sdata->local; 677 bool hw_scan = local->ops->hw_scan; 678 int rc; 679 680 lockdep_assert_held(&local->mtx); 681 682 if (local->scan_req) 683 return -EBUSY; 684 685 if (!__ieee80211_can_leave_ch(sdata)) 686 return -EBUSY; 687 688 if (!ieee80211_can_scan(local, sdata)) { 689 /* wait for the work to finish/time out */ 690 rcu_assign_pointer(local->scan_req, req); 691 rcu_assign_pointer(local->scan_sdata, sdata); 692 return 0; 693 } 694 695 again: 696 if (hw_scan) { 697 u8 *ies; 698 699 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len; 700 701 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 702 int i, n_bands = 0; 703 u8 bands_counted = 0; 704 705 for (i = 0; i < req->n_channels; i++) { 706 if (bands_counted & BIT(req->channels[i]->band)) 707 continue; 708 bands_counted |= BIT(req->channels[i]->band); 709 n_bands++; 710 } 711 712 local->hw_scan_ies_bufsize *= n_bands; 713 } 714 715 local->hw_scan_req = kmalloc( 716 sizeof(*local->hw_scan_req) + 717 req->n_channels * sizeof(req->channels[0]) + 718 local->hw_scan_ies_bufsize, GFP_KERNEL); 719 if (!local->hw_scan_req) 720 return -ENOMEM; 721 722 local->hw_scan_req->req.ssids = req->ssids; 723 local->hw_scan_req->req.n_ssids = req->n_ssids; 724 ies = (u8 *)local->hw_scan_req + 725 sizeof(*local->hw_scan_req) + 726 req->n_channels * sizeof(req->channels[0]); 727 local->hw_scan_req->req.ie = ies; 728 local->hw_scan_req->req.flags = req->flags; 729 eth_broadcast_addr(local->hw_scan_req->req.bssid); 730 local->hw_scan_req->req.duration = req->duration; 731 local->hw_scan_req->req.duration_mandatory = 732 req->duration_mandatory; 733 734 local->hw_scan_band = 0; 735 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params; 736 local->hw_scan_req->req.scan_6ghz_params = 737 req->scan_6ghz_params; 738 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz; 739 740 /* 741 * After allocating local->hw_scan_req, we must 742 * go through until ieee80211_prep_hw_scan(), so 743 * anything that might be changed here and leave 744 * this function early must not go after this 745 * allocation. 746 */ 747 } 748 749 rcu_assign_pointer(local->scan_req, req); 750 rcu_assign_pointer(local->scan_sdata, sdata); 751 752 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 753 get_random_mask_addr(local->scan_addr, 754 req->mac_addr, 755 req->mac_addr_mask); 756 else 757 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN); 758 759 if (hw_scan) { 760 __set_bit(SCAN_HW_SCANNING, &local->scanning); 761 } else if ((req->n_channels == 1) && 762 (req->channels[0] == local->_oper_chandef.chan)) { 763 /* 764 * If we are scanning only on the operating channel 765 * then we do not need to stop normal activities 766 */ 767 unsigned long next_delay; 768 769 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning); 770 771 ieee80211_recalc_idle(local); 772 773 /* Notify driver scan is starting, keep order of operations 774 * same as normal software scan, in case that matters. */ 775 drv_sw_scan_start(local, sdata, local->scan_addr); 776 777 ieee80211_configure_filter(local); /* accept probe-responses */ 778 779 /* We need to ensure power level is at max for scanning. */ 780 ieee80211_hw_config(local, 0); 781 782 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR | 783 IEEE80211_CHAN_RADAR)) || 784 !req->n_ssids) { 785 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 786 } else { 787 ieee80211_scan_state_send_probe(local, &next_delay); 788 next_delay = IEEE80211_CHANNEL_TIME; 789 } 790 791 /* Now, just wait a bit and we are all done! */ 792 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 793 next_delay); 794 return 0; 795 } else { 796 /* Do normal software scan */ 797 __set_bit(SCAN_SW_SCANNING, &local->scanning); 798 } 799 800 ieee80211_recalc_idle(local); 801 802 if (hw_scan) { 803 WARN_ON(!ieee80211_prep_hw_scan(sdata)); 804 rc = drv_hw_scan(local, sdata, local->hw_scan_req); 805 } else { 806 rc = ieee80211_start_sw_scan(local, sdata); 807 } 808 809 if (rc) { 810 kfree(local->hw_scan_req); 811 local->hw_scan_req = NULL; 812 local->scanning = 0; 813 814 ieee80211_recalc_idle(local); 815 816 local->scan_req = NULL; 817 RCU_INIT_POINTER(local->scan_sdata, NULL); 818 } 819 820 if (hw_scan && rc == 1) { 821 /* 822 * we can't fall back to software for P2P-GO 823 * as it must update NoA etc. 824 */ 825 if (ieee80211_vif_type_p2p(&sdata->vif) == 826 NL80211_IFTYPE_P2P_GO) 827 return -EOPNOTSUPP; 828 hw_scan = false; 829 goto again; 830 } 831 832 return rc; 833 } 834 835 static unsigned long 836 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) 837 { 838 /* 839 * TODO: channel switching also consumes quite some time, 840 * add that delay as well to get a better estimation 841 */ 842 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) 843 return IEEE80211_PASSIVE_CHANNEL_TIME; 844 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; 845 } 846 847 static void ieee80211_scan_state_decision(struct ieee80211_local *local, 848 unsigned long *next_delay) 849 { 850 bool associated = false; 851 bool tx_empty = true; 852 bool bad_latency; 853 struct ieee80211_sub_if_data *sdata; 854 struct ieee80211_channel *next_chan; 855 enum mac80211_scan_state next_scan_state; 856 struct cfg80211_scan_request *scan_req; 857 858 /* 859 * check if at least one STA interface is associated, 860 * check if at least one STA interface has pending tx frames 861 * and grab the lowest used beacon interval 862 */ 863 mutex_lock(&local->iflist_mtx); 864 list_for_each_entry(sdata, &local->interfaces, list) { 865 if (!ieee80211_sdata_running(sdata)) 866 continue; 867 868 if (sdata->vif.type == NL80211_IFTYPE_STATION) { 869 if (sdata->u.mgd.associated) { 870 associated = true; 871 872 if (!qdisc_all_tx_empty(sdata->dev)) { 873 tx_empty = false; 874 break; 875 } 876 } 877 } 878 } 879 mutex_unlock(&local->iflist_mtx); 880 881 scan_req = rcu_dereference_protected(local->scan_req, 882 lockdep_is_held(&local->mtx)); 883 884 next_chan = scan_req->channels[local->scan_channel_idx]; 885 886 /* 887 * we're currently scanning a different channel, let's 888 * see if we can scan another channel without interfering 889 * with the current traffic situation. 890 * 891 * Keep good latency, do not stay off-channel more than 125 ms. 892 */ 893 894 bad_latency = time_after(jiffies + 895 ieee80211_scan_get_channel_time(next_chan), 896 local->leave_oper_channel_time + HZ / 8); 897 898 if (associated && !tx_empty) { 899 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY) 900 next_scan_state = SCAN_ABORT; 901 else 902 next_scan_state = SCAN_SUSPEND; 903 } else if (associated && bad_latency) { 904 next_scan_state = SCAN_SUSPEND; 905 } else { 906 next_scan_state = SCAN_SET_CHANNEL; 907 } 908 909 local->next_scan_state = next_scan_state; 910 911 *next_delay = 0; 912 } 913 914 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, 915 unsigned long *next_delay) 916 { 917 int skip; 918 struct ieee80211_channel *chan; 919 enum nl80211_bss_scan_width oper_scan_width; 920 struct cfg80211_scan_request *scan_req; 921 922 scan_req = rcu_dereference_protected(local->scan_req, 923 lockdep_is_held(&local->mtx)); 924 925 skip = 0; 926 chan = scan_req->channels[local->scan_channel_idx]; 927 928 local->scan_chandef.chan = chan; 929 local->scan_chandef.center_freq1 = chan->center_freq; 930 local->scan_chandef.freq1_offset = chan->freq_offset; 931 local->scan_chandef.center_freq2 = 0; 932 933 /* For scanning on the S1G band, ignore scan_width (which is constant 934 * across all channels) for now since channel width is specific to each 935 * channel. Detect the required channel width here and likely revisit 936 * later. Maybe scan_width could be used to build the channel scan list? 937 */ 938 if (chan->band == NL80211_BAND_S1GHZ) { 939 local->scan_chandef.width = ieee80211_s1g_channel_width(chan); 940 goto set_channel; 941 } 942 943 switch (scan_req->scan_width) { 944 case NL80211_BSS_CHAN_WIDTH_5: 945 local->scan_chandef.width = NL80211_CHAN_WIDTH_5; 946 break; 947 case NL80211_BSS_CHAN_WIDTH_10: 948 local->scan_chandef.width = NL80211_CHAN_WIDTH_10; 949 break; 950 default: 951 case NL80211_BSS_CHAN_WIDTH_20: 952 /* If scanning on oper channel, use whatever channel-type 953 * is currently in use. 954 */ 955 oper_scan_width = cfg80211_chandef_to_scan_width( 956 &local->_oper_chandef); 957 if (chan == local->_oper_chandef.chan && 958 oper_scan_width == scan_req->scan_width) 959 local->scan_chandef = local->_oper_chandef; 960 else 961 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT; 962 break; 963 case NL80211_BSS_CHAN_WIDTH_1: 964 case NL80211_BSS_CHAN_WIDTH_2: 965 /* shouldn't get here, S1G handled above */ 966 WARN_ON(1); 967 break; 968 } 969 970 set_channel: 971 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) 972 skip = 1; 973 974 /* advance state machine to next channel/band */ 975 local->scan_channel_idx++; 976 977 if (skip) { 978 /* if we skip this channel return to the decision state */ 979 local->next_scan_state = SCAN_DECISION; 980 return; 981 } 982 983 /* 984 * Probe delay is used to update the NAV, cf. 11.1.3.2.2 985 * (which unfortunately doesn't say _why_ step a) is done, 986 * but it waits for the probe delay or until a frame is 987 * received - and the received frame would update the NAV). 988 * For now, we do not support waiting until a frame is 989 * received. 990 * 991 * In any case, it is not necessary for a passive scan. 992 */ 993 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) || 994 !scan_req->n_ssids) { 995 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 996 local->next_scan_state = SCAN_DECISION; 997 return; 998 } 999 1000 /* active scan, send probes */ 1001 *next_delay = IEEE80211_PROBE_DELAY; 1002 local->next_scan_state = SCAN_SEND_PROBE; 1003 } 1004 1005 static void ieee80211_scan_state_suspend(struct ieee80211_local *local, 1006 unsigned long *next_delay) 1007 { 1008 /* switch back to the operating channel */ 1009 local->scan_chandef.chan = NULL; 1010 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 1011 1012 /* disable PS */ 1013 ieee80211_offchannel_return(local); 1014 1015 *next_delay = HZ / 5; 1016 /* afterwards, resume scan & go to next channel */ 1017 local->next_scan_state = SCAN_RESUME; 1018 } 1019 1020 static void ieee80211_scan_state_resume(struct ieee80211_local *local, 1021 unsigned long *next_delay) 1022 { 1023 ieee80211_offchannel_stop_vifs(local); 1024 1025 if (local->ops->flush) { 1026 ieee80211_flush_queues(local, NULL, false); 1027 *next_delay = 0; 1028 } else 1029 *next_delay = HZ / 10; 1030 1031 /* remember when we left the operating channel */ 1032 local->leave_oper_channel_time = jiffies; 1033 1034 /* advance to the next channel to be scanned */ 1035 local->next_scan_state = SCAN_SET_CHANNEL; 1036 } 1037 1038 void ieee80211_scan_work(struct work_struct *work) 1039 { 1040 struct ieee80211_local *local = 1041 container_of(work, struct ieee80211_local, scan_work.work); 1042 struct ieee80211_sub_if_data *sdata; 1043 struct cfg80211_scan_request *scan_req; 1044 unsigned long next_delay = 0; 1045 bool aborted; 1046 1047 mutex_lock(&local->mtx); 1048 1049 if (!ieee80211_can_run_worker(local)) { 1050 aborted = true; 1051 goto out_complete; 1052 } 1053 1054 sdata = rcu_dereference_protected(local->scan_sdata, 1055 lockdep_is_held(&local->mtx)); 1056 scan_req = rcu_dereference_protected(local->scan_req, 1057 lockdep_is_held(&local->mtx)); 1058 1059 /* When scanning on-channel, the first-callback means completed. */ 1060 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) { 1061 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1062 goto out_complete; 1063 } 1064 1065 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) { 1066 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1067 goto out_complete; 1068 } 1069 1070 if (!sdata || !scan_req) 1071 goto out; 1072 1073 if (!local->scanning) { 1074 int rc; 1075 1076 RCU_INIT_POINTER(local->scan_req, NULL); 1077 RCU_INIT_POINTER(local->scan_sdata, NULL); 1078 1079 rc = __ieee80211_start_scan(sdata, scan_req); 1080 if (rc) { 1081 /* need to complete scan in cfg80211 */ 1082 rcu_assign_pointer(local->scan_req, scan_req); 1083 aborted = true; 1084 goto out_complete; 1085 } else 1086 goto out; 1087 } 1088 1089 /* 1090 * as long as no delay is required advance immediately 1091 * without scheduling a new work 1092 */ 1093 do { 1094 if (!ieee80211_sdata_running(sdata)) { 1095 aborted = true; 1096 goto out_complete; 1097 } 1098 1099 switch (local->next_scan_state) { 1100 case SCAN_DECISION: 1101 /* if no more bands/channels left, complete scan */ 1102 if (local->scan_channel_idx >= scan_req->n_channels) { 1103 aborted = false; 1104 goto out_complete; 1105 } 1106 ieee80211_scan_state_decision(local, &next_delay); 1107 break; 1108 case SCAN_SET_CHANNEL: 1109 ieee80211_scan_state_set_channel(local, &next_delay); 1110 break; 1111 case SCAN_SEND_PROBE: 1112 ieee80211_scan_state_send_probe(local, &next_delay); 1113 break; 1114 case SCAN_SUSPEND: 1115 ieee80211_scan_state_suspend(local, &next_delay); 1116 break; 1117 case SCAN_RESUME: 1118 ieee80211_scan_state_resume(local, &next_delay); 1119 break; 1120 case SCAN_ABORT: 1121 aborted = true; 1122 goto out_complete; 1123 } 1124 } while (next_delay == 0); 1125 1126 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay); 1127 goto out; 1128 1129 out_complete: 1130 __ieee80211_scan_completed(&local->hw, aborted); 1131 out: 1132 mutex_unlock(&local->mtx); 1133 } 1134 1135 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, 1136 struct cfg80211_scan_request *req) 1137 { 1138 int res; 1139 1140 mutex_lock(&sdata->local->mtx); 1141 res = __ieee80211_start_scan(sdata, req); 1142 mutex_unlock(&sdata->local->mtx); 1143 1144 return res; 1145 } 1146 1147 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata, 1148 const u8 *ssid, u8 ssid_len, 1149 struct ieee80211_channel **channels, 1150 unsigned int n_channels, 1151 enum nl80211_bss_scan_width scan_width) 1152 { 1153 struct ieee80211_local *local = sdata->local; 1154 int ret = -EBUSY, i, n_ch = 0; 1155 enum nl80211_band band; 1156 1157 mutex_lock(&local->mtx); 1158 1159 /* busy scanning */ 1160 if (local->scan_req) 1161 goto unlock; 1162 1163 /* fill internal scan request */ 1164 if (!channels) { 1165 int max_n; 1166 1167 for (band = 0; band < NUM_NL80211_BANDS; band++) { 1168 if (!local->hw.wiphy->bands[band] || 1169 band == NL80211_BAND_6GHZ) 1170 continue; 1171 1172 max_n = local->hw.wiphy->bands[band]->n_channels; 1173 for (i = 0; i < max_n; i++) { 1174 struct ieee80211_channel *tmp_ch = 1175 &local->hw.wiphy->bands[band]->channels[i]; 1176 1177 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR | 1178 IEEE80211_CHAN_DISABLED)) 1179 continue; 1180 1181 local->int_scan_req->channels[n_ch] = tmp_ch; 1182 n_ch++; 1183 } 1184 } 1185 1186 if (WARN_ON_ONCE(n_ch == 0)) 1187 goto unlock; 1188 1189 local->int_scan_req->n_channels = n_ch; 1190 } else { 1191 for (i = 0; i < n_channels; i++) { 1192 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR | 1193 IEEE80211_CHAN_DISABLED)) 1194 continue; 1195 1196 local->int_scan_req->channels[n_ch] = channels[i]; 1197 n_ch++; 1198 } 1199 1200 if (WARN_ON_ONCE(n_ch == 0)) 1201 goto unlock; 1202 1203 local->int_scan_req->n_channels = n_ch; 1204 } 1205 1206 local->int_scan_req->ssids = &local->scan_ssid; 1207 local->int_scan_req->n_ssids = 1; 1208 local->int_scan_req->scan_width = scan_width; 1209 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); 1210 local->int_scan_req->ssids[0].ssid_len = ssid_len; 1211 1212 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); 1213 unlock: 1214 mutex_unlock(&local->mtx); 1215 return ret; 1216 } 1217 1218 /* 1219 * Only call this function when a scan can't be queued -- under RTNL. 1220 */ 1221 void ieee80211_scan_cancel(struct ieee80211_local *local) 1222 { 1223 /* 1224 * We are canceling software scan, or deferred scan that was not 1225 * yet really started (see __ieee80211_start_scan ). 1226 * 1227 * Regarding hardware scan: 1228 * - we can not call __ieee80211_scan_completed() as when 1229 * SCAN_HW_SCANNING bit is set this function change 1230 * local->hw_scan_req to operate on 5G band, what race with 1231 * driver which can use local->hw_scan_req 1232 * 1233 * - we can not cancel scan_work since driver can schedule it 1234 * by ieee80211_scan_completed(..., true) to finish scan 1235 * 1236 * Hence we only call the cancel_hw_scan() callback, but the low-level 1237 * driver is still responsible for calling ieee80211_scan_completed() 1238 * after the scan was completed/aborted. 1239 */ 1240 1241 mutex_lock(&local->mtx); 1242 if (!local->scan_req) 1243 goto out; 1244 1245 /* 1246 * We have a scan running and the driver already reported completion, 1247 * but the worker hasn't run yet or is stuck on the mutex - mark it as 1248 * cancelled. 1249 */ 1250 if (test_bit(SCAN_HW_SCANNING, &local->scanning) && 1251 test_bit(SCAN_COMPLETED, &local->scanning)) { 1252 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1253 goto out; 1254 } 1255 1256 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) { 1257 /* 1258 * Make sure that __ieee80211_scan_completed doesn't trigger a 1259 * scan on another band. 1260 */ 1261 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1262 if (local->ops->cancel_hw_scan) 1263 drv_cancel_hw_scan(local, 1264 rcu_dereference_protected(local->scan_sdata, 1265 lockdep_is_held(&local->mtx))); 1266 goto out; 1267 } 1268 1269 /* 1270 * If the work is currently running, it must be blocked on 1271 * the mutex, but we'll set scan_sdata = NULL and it'll 1272 * simply exit once it acquires the mutex. 1273 */ 1274 cancel_delayed_work(&local->scan_work); 1275 /* and clean up */ 1276 memset(&local->scan_info, 0, sizeof(local->scan_info)); 1277 __ieee80211_scan_completed(&local->hw, true); 1278 out: 1279 mutex_unlock(&local->mtx); 1280 } 1281 1282 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1283 struct cfg80211_sched_scan_request *req) 1284 { 1285 struct ieee80211_local *local = sdata->local; 1286 struct ieee80211_scan_ies sched_scan_ies = {}; 1287 struct cfg80211_chan_def chandef; 1288 int ret, i, iebufsz, num_bands = 0; 1289 u32 rate_masks[NUM_NL80211_BANDS] = {}; 1290 u8 bands_used = 0; 1291 u8 *ie; 1292 u32 flags = 0; 1293 1294 iebufsz = local->scan_ies_len + req->ie_len; 1295 1296 lockdep_assert_held(&local->mtx); 1297 1298 if (!local->ops->sched_scan_start) 1299 return -ENOTSUPP; 1300 1301 for (i = 0; i < NUM_NL80211_BANDS; i++) { 1302 if (local->hw.wiphy->bands[i]) { 1303 bands_used |= BIT(i); 1304 rate_masks[i] = (u32) -1; 1305 num_bands++; 1306 } 1307 } 1308 1309 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 1310 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 1311 1312 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL); 1313 if (!ie) { 1314 ret = -ENOMEM; 1315 goto out; 1316 } 1317 1318 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 1319 1320 ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz, 1321 &sched_scan_ies, req->ie, 1322 req->ie_len, bands_used, rate_masks, &chandef, 1323 flags); 1324 1325 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies); 1326 if (ret == 0) { 1327 rcu_assign_pointer(local->sched_scan_sdata, sdata); 1328 rcu_assign_pointer(local->sched_scan_req, req); 1329 } 1330 1331 kfree(ie); 1332 1333 out: 1334 if (ret) { 1335 /* Clean in case of failure after HW restart or upon resume. */ 1336 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1337 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1338 } 1339 1340 return ret; 1341 } 1342 1343 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1344 struct cfg80211_sched_scan_request *req) 1345 { 1346 struct ieee80211_local *local = sdata->local; 1347 int ret; 1348 1349 mutex_lock(&local->mtx); 1350 1351 if (rcu_access_pointer(local->sched_scan_sdata)) { 1352 mutex_unlock(&local->mtx); 1353 return -EBUSY; 1354 } 1355 1356 ret = __ieee80211_request_sched_scan_start(sdata, req); 1357 1358 mutex_unlock(&local->mtx); 1359 return ret; 1360 } 1361 1362 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local) 1363 { 1364 struct ieee80211_sub_if_data *sched_scan_sdata; 1365 int ret = -ENOENT; 1366 1367 mutex_lock(&local->mtx); 1368 1369 if (!local->ops->sched_scan_stop) { 1370 ret = -ENOTSUPP; 1371 goto out; 1372 } 1373 1374 /* We don't want to restart sched scan anymore. */ 1375 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1376 1377 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata, 1378 lockdep_is_held(&local->mtx)); 1379 if (sched_scan_sdata) { 1380 ret = drv_sched_scan_stop(local, sched_scan_sdata); 1381 if (!ret) 1382 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1383 } 1384 out: 1385 mutex_unlock(&local->mtx); 1386 1387 return ret; 1388 } 1389 1390 void ieee80211_sched_scan_results(struct ieee80211_hw *hw) 1391 { 1392 struct ieee80211_local *local = hw_to_local(hw); 1393 1394 trace_api_sched_scan_results(local); 1395 1396 cfg80211_sched_scan_results(hw->wiphy, 0); 1397 } 1398 EXPORT_SYMBOL(ieee80211_sched_scan_results); 1399 1400 void ieee80211_sched_scan_end(struct ieee80211_local *local) 1401 { 1402 mutex_lock(&local->mtx); 1403 1404 if (!rcu_access_pointer(local->sched_scan_sdata)) { 1405 mutex_unlock(&local->mtx); 1406 return; 1407 } 1408 1409 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1410 1411 /* If sched scan was aborted by the driver. */ 1412 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1413 1414 mutex_unlock(&local->mtx); 1415 1416 cfg80211_sched_scan_stopped(local->hw.wiphy, 0); 1417 } 1418 1419 void ieee80211_sched_scan_stopped_work(struct work_struct *work) 1420 { 1421 struct ieee80211_local *local = 1422 container_of(work, struct ieee80211_local, 1423 sched_scan_stopped_work); 1424 1425 ieee80211_sched_scan_end(local); 1426 } 1427 1428 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw) 1429 { 1430 struct ieee80211_local *local = hw_to_local(hw); 1431 1432 trace_api_sched_scan_stopped(local); 1433 1434 /* 1435 * this shouldn't really happen, so for simplicity 1436 * simply ignore it, and let mac80211 reconfigure 1437 * the sched scan later on. 1438 */ 1439 if (local->in_reconfig) 1440 return; 1441 1442 schedule_work(&local->sched_scan_stopped_work); 1443 } 1444 EXPORT_SYMBOL(ieee80211_sched_scan_stopped); 1445