1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * cfg80211 scan result handling 4 * 5 * Copyright 2008 Johannes Berg <johannes@sipsolutions.net> 6 * Copyright 2013-2014 Intel Mobile Communications GmbH 7 * Copyright 2016 Intel Deutschland GmbH 8 * Copyright (C) 2018-2019 Intel Corporation 9 */ 10 #include <linux/kernel.h> 11 #include <linux/slab.h> 12 #include <linux/module.h> 13 #include <linux/netdevice.h> 14 #include <linux/wireless.h> 15 #include <linux/nl80211.h> 16 #include <linux/etherdevice.h> 17 #include <net/arp.h> 18 #include <net/cfg80211.h> 19 #include <net/cfg80211-wext.h> 20 #include <net/iw_handler.h> 21 #include "core.h" 22 #include "nl80211.h" 23 #include "wext-compat.h" 24 #include "rdev-ops.h" 25 26 /** 27 * DOC: BSS tree/list structure 28 * 29 * At the top level, the BSS list is kept in both a list in each 30 * registered device (@bss_list) as well as an RB-tree for faster 31 * lookup. In the RB-tree, entries can be looked up using their 32 * channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID 33 * for other BSSes. 34 * 35 * Due to the possibility of hidden SSIDs, there's a second level 36 * structure, the "hidden_list" and "hidden_beacon_bss" pointer. 37 * The hidden_list connects all BSSes belonging to a single AP 38 * that has a hidden SSID, and connects beacon and probe response 39 * entries. For a probe response entry for a hidden SSID, the 40 * hidden_beacon_bss pointer points to the BSS struct holding the 41 * beacon's information. 42 * 43 * Reference counting is done for all these references except for 44 * the hidden_list, so that a beacon BSS struct that is otherwise 45 * not referenced has one reference for being on the bss_list and 46 * one for each probe response entry that points to it using the 47 * hidden_beacon_bss pointer. When a BSS struct that has such a 48 * pointer is get/put, the refcount update is also propagated to 49 * the referenced struct, this ensure that it cannot get removed 50 * while somebody is using the probe response version. 51 * 52 * Note that the hidden_beacon_bss pointer never changes, due to 53 * the reference counting. Therefore, no locking is needed for 54 * it. 55 * 56 * Also note that the hidden_beacon_bss pointer is only relevant 57 * if the driver uses something other than the IEs, e.g. private 58 * data stored stored in the BSS struct, since the beacon IEs are 59 * also linked into the probe response struct. 60 */ 61 62 /* 63 * Limit the number of BSS entries stored in mac80211. Each one is 64 * a bit over 4k at most, so this limits to roughly 4-5M of memory. 65 * If somebody wants to really attack this though, they'd likely 66 * use small beacons, and only one type of frame, limiting each of 67 * the entries to a much smaller size (in order to generate more 68 * entries in total, so overhead is bigger.) 69 */ 70 static int bss_entries_limit = 1000; 71 module_param(bss_entries_limit, int, 0644); 72 MODULE_PARM_DESC(bss_entries_limit, 73 "limit to number of scan BSS entries (per wiphy, default 1000)"); 74 75 #define IEEE80211_SCAN_RESULT_EXPIRE (30 * HZ) 76 77 static void bss_free(struct cfg80211_internal_bss *bss) 78 { 79 struct cfg80211_bss_ies *ies; 80 81 if (WARN_ON(atomic_read(&bss->hold))) 82 return; 83 84 ies = (void *)rcu_access_pointer(bss->pub.beacon_ies); 85 if (ies && !bss->pub.hidden_beacon_bss) 86 kfree_rcu(ies, rcu_head); 87 ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies); 88 if (ies) 89 kfree_rcu(ies, rcu_head); 90 91 /* 92 * This happens when the module is removed, it doesn't 93 * really matter any more save for completeness 94 */ 95 if (!list_empty(&bss->hidden_list)) 96 list_del(&bss->hidden_list); 97 98 kfree(bss); 99 } 100 101 static inline void bss_ref_get(struct cfg80211_registered_device *rdev, 102 struct cfg80211_internal_bss *bss) 103 { 104 lockdep_assert_held(&rdev->bss_lock); 105 106 bss->refcount++; 107 if (bss->pub.hidden_beacon_bss) { 108 bss = container_of(bss->pub.hidden_beacon_bss, 109 struct cfg80211_internal_bss, 110 pub); 111 bss->refcount++; 112 } 113 if (bss->pub.transmitted_bss) { 114 bss = container_of(bss->pub.transmitted_bss, 115 struct cfg80211_internal_bss, 116 pub); 117 bss->refcount++; 118 } 119 } 120 121 static inline void bss_ref_put(struct cfg80211_registered_device *rdev, 122 struct cfg80211_internal_bss *bss) 123 { 124 lockdep_assert_held(&rdev->bss_lock); 125 126 if (bss->pub.hidden_beacon_bss) { 127 struct cfg80211_internal_bss *hbss; 128 hbss = container_of(bss->pub.hidden_beacon_bss, 129 struct cfg80211_internal_bss, 130 pub); 131 hbss->refcount--; 132 if (hbss->refcount == 0) 133 bss_free(hbss); 134 } 135 136 if (bss->pub.transmitted_bss) { 137 struct cfg80211_internal_bss *tbss; 138 139 tbss = container_of(bss->pub.transmitted_bss, 140 struct cfg80211_internal_bss, 141 pub); 142 tbss->refcount--; 143 if (tbss->refcount == 0) 144 bss_free(tbss); 145 } 146 147 bss->refcount--; 148 if (bss->refcount == 0) 149 bss_free(bss); 150 } 151 152 static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev, 153 struct cfg80211_internal_bss *bss) 154 { 155 lockdep_assert_held(&rdev->bss_lock); 156 157 if (!list_empty(&bss->hidden_list)) { 158 /* 159 * don't remove the beacon entry if it has 160 * probe responses associated with it 161 */ 162 if (!bss->pub.hidden_beacon_bss) 163 return false; 164 /* 165 * if it's a probe response entry break its 166 * link to the other entries in the group 167 */ 168 list_del_init(&bss->hidden_list); 169 } 170 171 list_del_init(&bss->list); 172 list_del_init(&bss->pub.nontrans_list); 173 rb_erase(&bss->rbn, &rdev->bss_tree); 174 rdev->bss_entries--; 175 WARN_ONCE((rdev->bss_entries == 0) ^ list_empty(&rdev->bss_list), 176 "rdev bss entries[%d]/list[empty:%d] corruption\n", 177 rdev->bss_entries, list_empty(&rdev->bss_list)); 178 bss_ref_put(rdev, bss); 179 return true; 180 } 181 182 bool cfg80211_is_element_inherited(const struct element *elem, 183 const struct element *non_inherit_elem) 184 { 185 u8 id_len, ext_id_len, i, loop_len, id; 186 const u8 *list; 187 188 if (elem->id == WLAN_EID_MULTIPLE_BSSID) 189 return false; 190 191 if (!non_inherit_elem || non_inherit_elem->datalen < 2) 192 return true; 193 194 /* 195 * non inheritance element format is: 196 * ext ID (56) | IDs list len | list | extension IDs list len | list 197 * Both lists are optional. Both lengths are mandatory. 198 * This means valid length is: 199 * elem_len = 1 (extension ID) + 2 (list len fields) + list lengths 200 */ 201 id_len = non_inherit_elem->data[1]; 202 if (non_inherit_elem->datalen < 3 + id_len) 203 return true; 204 205 ext_id_len = non_inherit_elem->data[2 + id_len]; 206 if (non_inherit_elem->datalen < 3 + id_len + ext_id_len) 207 return true; 208 209 if (elem->id == WLAN_EID_EXTENSION) { 210 if (!ext_id_len) 211 return true; 212 loop_len = ext_id_len; 213 list = &non_inherit_elem->data[3 + id_len]; 214 id = elem->data[0]; 215 } else { 216 if (!id_len) 217 return true; 218 loop_len = id_len; 219 list = &non_inherit_elem->data[2]; 220 id = elem->id; 221 } 222 223 for (i = 0; i < loop_len; i++) { 224 if (list[i] == id) 225 return false; 226 } 227 228 return true; 229 } 230 EXPORT_SYMBOL(cfg80211_is_element_inherited); 231 232 static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen, 233 const u8 *subelement, size_t subie_len, 234 u8 *new_ie, gfp_t gfp) 235 { 236 u8 *pos, *tmp; 237 const u8 *tmp_old, *tmp_new; 238 const struct element *non_inherit_elem; 239 u8 *sub_copy; 240 241 /* copy subelement as we need to change its content to 242 * mark an ie after it is processed. 243 */ 244 sub_copy = kmemdup(subelement, subie_len, gfp); 245 if (!sub_copy) 246 return 0; 247 248 pos = &new_ie[0]; 249 250 /* set new ssid */ 251 tmp_new = cfg80211_find_ie(WLAN_EID_SSID, sub_copy, subie_len); 252 if (tmp_new) { 253 memcpy(pos, tmp_new, tmp_new[1] + 2); 254 pos += (tmp_new[1] + 2); 255 } 256 257 /* get non inheritance list if exists */ 258 non_inherit_elem = 259 cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE, 260 sub_copy, subie_len); 261 262 /* go through IEs in ie (skip SSID) and subelement, 263 * merge them into new_ie 264 */ 265 tmp_old = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen); 266 tmp_old = (tmp_old) ? tmp_old + tmp_old[1] + 2 : ie; 267 268 while (tmp_old + tmp_old[1] + 2 - ie <= ielen) { 269 if (tmp_old[0] == 0) { 270 tmp_old++; 271 continue; 272 } 273 274 if (tmp_old[0] == WLAN_EID_EXTENSION) 275 tmp = (u8 *)cfg80211_find_ext_ie(tmp_old[2], sub_copy, 276 subie_len); 277 else 278 tmp = (u8 *)cfg80211_find_ie(tmp_old[0], sub_copy, 279 subie_len); 280 281 if (!tmp) { 282 const struct element *old_elem = (void *)tmp_old; 283 284 /* ie in old ie but not in subelement */ 285 if (cfg80211_is_element_inherited(old_elem, 286 non_inherit_elem)) { 287 memcpy(pos, tmp_old, tmp_old[1] + 2); 288 pos += tmp_old[1] + 2; 289 } 290 } else { 291 /* ie in transmitting ie also in subelement, 292 * copy from subelement and flag the ie in subelement 293 * as copied (by setting eid field to WLAN_EID_SSID, 294 * which is skipped anyway). 295 * For vendor ie, compare OUI + type + subType to 296 * determine if they are the same ie. 297 */ 298 if (tmp_old[0] == WLAN_EID_VENDOR_SPECIFIC) { 299 if (!memcmp(tmp_old + 2, tmp + 2, 5)) { 300 /* same vendor ie, copy from 301 * subelement 302 */ 303 memcpy(pos, tmp, tmp[1] + 2); 304 pos += tmp[1] + 2; 305 tmp[0] = WLAN_EID_SSID; 306 } else { 307 memcpy(pos, tmp_old, tmp_old[1] + 2); 308 pos += tmp_old[1] + 2; 309 } 310 } else { 311 /* copy ie from subelement into new ie */ 312 memcpy(pos, tmp, tmp[1] + 2); 313 pos += tmp[1] + 2; 314 tmp[0] = WLAN_EID_SSID; 315 } 316 } 317 318 if (tmp_old + tmp_old[1] + 2 - ie == ielen) 319 break; 320 321 tmp_old += tmp_old[1] + 2; 322 } 323 324 /* go through subelement again to check if there is any ie not 325 * copied to new ie, skip ssid, capability, bssid-index ie 326 */ 327 tmp_new = sub_copy; 328 while (tmp_new + tmp_new[1] + 2 - sub_copy <= subie_len) { 329 if (!(tmp_new[0] == WLAN_EID_NON_TX_BSSID_CAP || 330 tmp_new[0] == WLAN_EID_SSID)) { 331 memcpy(pos, tmp_new, tmp_new[1] + 2); 332 pos += tmp_new[1] + 2; 333 } 334 if (tmp_new + tmp_new[1] + 2 - sub_copy == subie_len) 335 break; 336 tmp_new += tmp_new[1] + 2; 337 } 338 339 kfree(sub_copy); 340 return pos - new_ie; 341 } 342 343 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid, 344 const u8 *ssid, size_t ssid_len) 345 { 346 const struct cfg80211_bss_ies *ies; 347 const u8 *ssidie; 348 349 if (bssid && !ether_addr_equal(a->bssid, bssid)) 350 return false; 351 352 if (!ssid) 353 return true; 354 355 ies = rcu_access_pointer(a->ies); 356 if (!ies) 357 return false; 358 ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 359 if (!ssidie) 360 return false; 361 if (ssidie[1] != ssid_len) 362 return false; 363 return memcmp(ssidie + 2, ssid, ssid_len) == 0; 364 } 365 366 static int 367 cfg80211_add_nontrans_list(struct cfg80211_bss *trans_bss, 368 struct cfg80211_bss *nontrans_bss) 369 { 370 const u8 *ssid; 371 size_t ssid_len; 372 struct cfg80211_bss *bss = NULL; 373 374 rcu_read_lock(); 375 ssid = ieee80211_bss_get_ie(nontrans_bss, WLAN_EID_SSID); 376 if (!ssid) { 377 rcu_read_unlock(); 378 return -EINVAL; 379 } 380 ssid_len = ssid[1]; 381 ssid = ssid + 2; 382 rcu_read_unlock(); 383 384 /* check if nontrans_bss is in the list */ 385 list_for_each_entry(bss, &trans_bss->nontrans_list, nontrans_list) { 386 if (is_bss(bss, nontrans_bss->bssid, ssid, ssid_len)) 387 return 0; 388 } 389 390 /* add to the list */ 391 list_add_tail(&nontrans_bss->nontrans_list, &trans_bss->nontrans_list); 392 return 0; 393 } 394 395 static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev, 396 unsigned long expire_time) 397 { 398 struct cfg80211_internal_bss *bss, *tmp; 399 bool expired = false; 400 401 lockdep_assert_held(&rdev->bss_lock); 402 403 list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) { 404 if (atomic_read(&bss->hold)) 405 continue; 406 if (!time_after(expire_time, bss->ts)) 407 continue; 408 409 if (__cfg80211_unlink_bss(rdev, bss)) 410 expired = true; 411 } 412 413 if (expired) 414 rdev->bss_generation++; 415 } 416 417 static bool cfg80211_bss_expire_oldest(struct cfg80211_registered_device *rdev) 418 { 419 struct cfg80211_internal_bss *bss, *oldest = NULL; 420 bool ret; 421 422 lockdep_assert_held(&rdev->bss_lock); 423 424 list_for_each_entry(bss, &rdev->bss_list, list) { 425 if (atomic_read(&bss->hold)) 426 continue; 427 428 if (!list_empty(&bss->hidden_list) && 429 !bss->pub.hidden_beacon_bss) 430 continue; 431 432 if (oldest && time_before(oldest->ts, bss->ts)) 433 continue; 434 oldest = bss; 435 } 436 437 if (WARN_ON(!oldest)) 438 return false; 439 440 /* 441 * The callers make sure to increase rdev->bss_generation if anything 442 * gets removed (and a new entry added), so there's no need to also do 443 * it here. 444 */ 445 446 ret = __cfg80211_unlink_bss(rdev, oldest); 447 WARN_ON(!ret); 448 return ret; 449 } 450 451 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev, 452 bool send_message) 453 { 454 struct cfg80211_scan_request *request; 455 struct wireless_dev *wdev; 456 struct sk_buff *msg; 457 #ifdef CONFIG_CFG80211_WEXT 458 union iwreq_data wrqu; 459 #endif 460 461 ASSERT_RTNL(); 462 463 if (rdev->scan_msg) { 464 nl80211_send_scan_msg(rdev, rdev->scan_msg); 465 rdev->scan_msg = NULL; 466 return; 467 } 468 469 request = rdev->scan_req; 470 if (!request) 471 return; 472 473 wdev = request->wdev; 474 475 /* 476 * This must be before sending the other events! 477 * Otherwise, wpa_supplicant gets completely confused with 478 * wext events. 479 */ 480 if (wdev->netdev) 481 cfg80211_sme_scan_done(wdev->netdev); 482 483 if (!request->info.aborted && 484 request->flags & NL80211_SCAN_FLAG_FLUSH) { 485 /* flush entries from previous scans */ 486 spin_lock_bh(&rdev->bss_lock); 487 __cfg80211_bss_expire(rdev, request->scan_start); 488 spin_unlock_bh(&rdev->bss_lock); 489 } 490 491 msg = nl80211_build_scan_msg(rdev, wdev, request->info.aborted); 492 493 #ifdef CONFIG_CFG80211_WEXT 494 if (wdev->netdev && !request->info.aborted) { 495 memset(&wrqu, 0, sizeof(wrqu)); 496 497 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL); 498 } 499 #endif 500 501 if (wdev->netdev) 502 dev_put(wdev->netdev); 503 504 rdev->scan_req = NULL; 505 kfree(request); 506 507 if (!send_message) 508 rdev->scan_msg = msg; 509 else 510 nl80211_send_scan_msg(rdev, msg); 511 } 512 513 void __cfg80211_scan_done(struct work_struct *wk) 514 { 515 struct cfg80211_registered_device *rdev; 516 517 rdev = container_of(wk, struct cfg80211_registered_device, 518 scan_done_wk); 519 520 rtnl_lock(); 521 ___cfg80211_scan_done(rdev, true); 522 rtnl_unlock(); 523 } 524 525 void cfg80211_scan_done(struct cfg80211_scan_request *request, 526 struct cfg80211_scan_info *info) 527 { 528 trace_cfg80211_scan_done(request, info); 529 WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req); 530 531 request->info = *info; 532 request->notified = true; 533 queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk); 534 } 535 EXPORT_SYMBOL(cfg80211_scan_done); 536 537 void cfg80211_add_sched_scan_req(struct cfg80211_registered_device *rdev, 538 struct cfg80211_sched_scan_request *req) 539 { 540 ASSERT_RTNL(); 541 542 list_add_rcu(&req->list, &rdev->sched_scan_req_list); 543 } 544 545 static void cfg80211_del_sched_scan_req(struct cfg80211_registered_device *rdev, 546 struct cfg80211_sched_scan_request *req) 547 { 548 ASSERT_RTNL(); 549 550 list_del_rcu(&req->list); 551 kfree_rcu(req, rcu_head); 552 } 553 554 static struct cfg80211_sched_scan_request * 555 cfg80211_find_sched_scan_req(struct cfg80211_registered_device *rdev, u64 reqid) 556 { 557 struct cfg80211_sched_scan_request *pos; 558 559 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 560 561 list_for_each_entry_rcu(pos, &rdev->sched_scan_req_list, list) { 562 if (pos->reqid == reqid) 563 return pos; 564 } 565 return NULL; 566 } 567 568 /* 569 * Determines if a scheduled scan request can be handled. When a legacy 570 * scheduled scan is running no other scheduled scan is allowed regardless 571 * whether the request is for legacy or multi-support scan. When a multi-support 572 * scheduled scan is running a request for legacy scan is not allowed. In this 573 * case a request for multi-support scan can be handled if resources are 574 * available, ie. struct wiphy::max_sched_scan_reqs limit is not yet reached. 575 */ 576 int cfg80211_sched_scan_req_possible(struct cfg80211_registered_device *rdev, 577 bool want_multi) 578 { 579 struct cfg80211_sched_scan_request *pos; 580 int i = 0; 581 582 list_for_each_entry(pos, &rdev->sched_scan_req_list, list) { 583 /* request id zero means legacy in progress */ 584 if (!i && !pos->reqid) 585 return -EINPROGRESS; 586 i++; 587 } 588 589 if (i) { 590 /* no legacy allowed when multi request(s) are active */ 591 if (!want_multi) 592 return -EINPROGRESS; 593 594 /* resource limit reached */ 595 if (i == rdev->wiphy.max_sched_scan_reqs) 596 return -ENOSPC; 597 } 598 return 0; 599 } 600 601 void cfg80211_sched_scan_results_wk(struct work_struct *work) 602 { 603 struct cfg80211_registered_device *rdev; 604 struct cfg80211_sched_scan_request *req, *tmp; 605 606 rdev = container_of(work, struct cfg80211_registered_device, 607 sched_scan_res_wk); 608 609 rtnl_lock(); 610 list_for_each_entry_safe(req, tmp, &rdev->sched_scan_req_list, list) { 611 if (req->report_results) { 612 req->report_results = false; 613 if (req->flags & NL80211_SCAN_FLAG_FLUSH) { 614 /* flush entries from previous scans */ 615 spin_lock_bh(&rdev->bss_lock); 616 __cfg80211_bss_expire(rdev, req->scan_start); 617 spin_unlock_bh(&rdev->bss_lock); 618 req->scan_start = jiffies; 619 } 620 nl80211_send_sched_scan(req, 621 NL80211_CMD_SCHED_SCAN_RESULTS); 622 } 623 } 624 rtnl_unlock(); 625 } 626 627 void cfg80211_sched_scan_results(struct wiphy *wiphy, u64 reqid) 628 { 629 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 630 struct cfg80211_sched_scan_request *request; 631 632 trace_cfg80211_sched_scan_results(wiphy, reqid); 633 /* ignore if we're not scanning */ 634 635 rcu_read_lock(); 636 request = cfg80211_find_sched_scan_req(rdev, reqid); 637 if (request) { 638 request->report_results = true; 639 queue_work(cfg80211_wq, &rdev->sched_scan_res_wk); 640 } 641 rcu_read_unlock(); 642 } 643 EXPORT_SYMBOL(cfg80211_sched_scan_results); 644 645 void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy, u64 reqid) 646 { 647 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 648 649 ASSERT_RTNL(); 650 651 trace_cfg80211_sched_scan_stopped(wiphy, reqid); 652 653 __cfg80211_stop_sched_scan(rdev, reqid, true); 654 } 655 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_rtnl); 656 657 void cfg80211_sched_scan_stopped(struct wiphy *wiphy, u64 reqid) 658 { 659 rtnl_lock(); 660 cfg80211_sched_scan_stopped_rtnl(wiphy, reqid); 661 rtnl_unlock(); 662 } 663 EXPORT_SYMBOL(cfg80211_sched_scan_stopped); 664 665 int cfg80211_stop_sched_scan_req(struct cfg80211_registered_device *rdev, 666 struct cfg80211_sched_scan_request *req, 667 bool driver_initiated) 668 { 669 ASSERT_RTNL(); 670 671 if (!driver_initiated) { 672 int err = rdev_sched_scan_stop(rdev, req->dev, req->reqid); 673 if (err) 674 return err; 675 } 676 677 nl80211_send_sched_scan(req, NL80211_CMD_SCHED_SCAN_STOPPED); 678 679 cfg80211_del_sched_scan_req(rdev, req); 680 681 return 0; 682 } 683 684 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev, 685 u64 reqid, bool driver_initiated) 686 { 687 struct cfg80211_sched_scan_request *sched_scan_req; 688 689 ASSERT_RTNL(); 690 691 sched_scan_req = cfg80211_find_sched_scan_req(rdev, reqid); 692 if (!sched_scan_req) 693 return -ENOENT; 694 695 return cfg80211_stop_sched_scan_req(rdev, sched_scan_req, 696 driver_initiated); 697 } 698 699 void cfg80211_bss_age(struct cfg80211_registered_device *rdev, 700 unsigned long age_secs) 701 { 702 struct cfg80211_internal_bss *bss; 703 unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC); 704 705 spin_lock_bh(&rdev->bss_lock); 706 list_for_each_entry(bss, &rdev->bss_list, list) 707 bss->ts -= age_jiffies; 708 spin_unlock_bh(&rdev->bss_lock); 709 } 710 711 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev) 712 { 713 __cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE); 714 } 715 716 const struct element * 717 cfg80211_find_elem_match(u8 eid, const u8 *ies, unsigned int len, 718 const u8 *match, unsigned int match_len, 719 unsigned int match_offset) 720 { 721 const struct element *elem; 722 723 for_each_element_id(elem, eid, ies, len) { 724 if (elem->datalen >= match_offset + match_len && 725 !memcmp(elem->data + match_offset, match, match_len)) 726 return elem; 727 } 728 729 return NULL; 730 } 731 EXPORT_SYMBOL(cfg80211_find_elem_match); 732 733 const struct element *cfg80211_find_vendor_elem(unsigned int oui, int oui_type, 734 const u8 *ies, 735 unsigned int len) 736 { 737 const struct element *elem; 738 u8 match[] = { oui >> 16, oui >> 8, oui, oui_type }; 739 int match_len = (oui_type < 0) ? 3 : sizeof(match); 740 741 if (WARN_ON(oui_type > 0xff)) 742 return NULL; 743 744 elem = cfg80211_find_elem_match(WLAN_EID_VENDOR_SPECIFIC, ies, len, 745 match, match_len, 0); 746 747 if (!elem || elem->datalen < 4) 748 return NULL; 749 750 return elem; 751 } 752 EXPORT_SYMBOL(cfg80211_find_vendor_elem); 753 754 /** 755 * enum bss_compare_mode - BSS compare mode 756 * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find) 757 * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode 758 * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode 759 */ 760 enum bss_compare_mode { 761 BSS_CMP_REGULAR, 762 BSS_CMP_HIDE_ZLEN, 763 BSS_CMP_HIDE_NUL, 764 }; 765 766 static int cmp_bss(struct cfg80211_bss *a, 767 struct cfg80211_bss *b, 768 enum bss_compare_mode mode) 769 { 770 const struct cfg80211_bss_ies *a_ies, *b_ies; 771 const u8 *ie1 = NULL; 772 const u8 *ie2 = NULL; 773 int i, r; 774 775 if (a->channel != b->channel) 776 return b->channel->center_freq - a->channel->center_freq; 777 778 a_ies = rcu_access_pointer(a->ies); 779 if (!a_ies) 780 return -1; 781 b_ies = rcu_access_pointer(b->ies); 782 if (!b_ies) 783 return 1; 784 785 if (WLAN_CAPABILITY_IS_STA_BSS(a->capability)) 786 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID, 787 a_ies->data, a_ies->len); 788 if (WLAN_CAPABILITY_IS_STA_BSS(b->capability)) 789 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID, 790 b_ies->data, b_ies->len); 791 if (ie1 && ie2) { 792 int mesh_id_cmp; 793 794 if (ie1[1] == ie2[1]) 795 mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]); 796 else 797 mesh_id_cmp = ie2[1] - ie1[1]; 798 799 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, 800 a_ies->data, a_ies->len); 801 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, 802 b_ies->data, b_ies->len); 803 if (ie1 && ie2) { 804 if (mesh_id_cmp) 805 return mesh_id_cmp; 806 if (ie1[1] != ie2[1]) 807 return ie2[1] - ie1[1]; 808 return memcmp(ie1 + 2, ie2 + 2, ie1[1]); 809 } 810 } 811 812 r = memcmp(a->bssid, b->bssid, sizeof(a->bssid)); 813 if (r) 814 return r; 815 816 ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len); 817 ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len); 818 819 if (!ie1 && !ie2) 820 return 0; 821 822 /* 823 * Note that with "hide_ssid", the function returns a match if 824 * the already-present BSS ("b") is a hidden SSID beacon for 825 * the new BSS ("a"). 826 */ 827 828 /* sort missing IE before (left of) present IE */ 829 if (!ie1) 830 return -1; 831 if (!ie2) 832 return 1; 833 834 switch (mode) { 835 case BSS_CMP_HIDE_ZLEN: 836 /* 837 * In ZLEN mode we assume the BSS entry we're 838 * looking for has a zero-length SSID. So if 839 * the one we're looking at right now has that, 840 * return 0. Otherwise, return the difference 841 * in length, but since we're looking for the 842 * 0-length it's really equivalent to returning 843 * the length of the one we're looking at. 844 * 845 * No content comparison is needed as we assume 846 * the content length is zero. 847 */ 848 return ie2[1]; 849 case BSS_CMP_REGULAR: 850 default: 851 /* sort by length first, then by contents */ 852 if (ie1[1] != ie2[1]) 853 return ie2[1] - ie1[1]; 854 return memcmp(ie1 + 2, ie2 + 2, ie1[1]); 855 case BSS_CMP_HIDE_NUL: 856 if (ie1[1] != ie2[1]) 857 return ie2[1] - ie1[1]; 858 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */ 859 for (i = 0; i < ie2[1]; i++) 860 if (ie2[i + 2]) 861 return -1; 862 return 0; 863 } 864 } 865 866 static bool cfg80211_bss_type_match(u16 capability, 867 enum nl80211_band band, 868 enum ieee80211_bss_type bss_type) 869 { 870 bool ret = true; 871 u16 mask, val; 872 873 if (bss_type == IEEE80211_BSS_TYPE_ANY) 874 return ret; 875 876 if (band == NL80211_BAND_60GHZ) { 877 mask = WLAN_CAPABILITY_DMG_TYPE_MASK; 878 switch (bss_type) { 879 case IEEE80211_BSS_TYPE_ESS: 880 val = WLAN_CAPABILITY_DMG_TYPE_AP; 881 break; 882 case IEEE80211_BSS_TYPE_PBSS: 883 val = WLAN_CAPABILITY_DMG_TYPE_PBSS; 884 break; 885 case IEEE80211_BSS_TYPE_IBSS: 886 val = WLAN_CAPABILITY_DMG_TYPE_IBSS; 887 break; 888 default: 889 return false; 890 } 891 } else { 892 mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS; 893 switch (bss_type) { 894 case IEEE80211_BSS_TYPE_ESS: 895 val = WLAN_CAPABILITY_ESS; 896 break; 897 case IEEE80211_BSS_TYPE_IBSS: 898 val = WLAN_CAPABILITY_IBSS; 899 break; 900 case IEEE80211_BSS_TYPE_MBSS: 901 val = 0; 902 break; 903 default: 904 return false; 905 } 906 } 907 908 ret = ((capability & mask) == val); 909 return ret; 910 } 911 912 /* Returned bss is reference counted and must be cleaned up appropriately. */ 913 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy, 914 struct ieee80211_channel *channel, 915 const u8 *bssid, 916 const u8 *ssid, size_t ssid_len, 917 enum ieee80211_bss_type bss_type, 918 enum ieee80211_privacy privacy) 919 { 920 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 921 struct cfg80211_internal_bss *bss, *res = NULL; 922 unsigned long now = jiffies; 923 int bss_privacy; 924 925 trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type, 926 privacy); 927 928 spin_lock_bh(&rdev->bss_lock); 929 930 list_for_each_entry(bss, &rdev->bss_list, list) { 931 if (!cfg80211_bss_type_match(bss->pub.capability, 932 bss->pub.channel->band, bss_type)) 933 continue; 934 935 bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY); 936 if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) || 937 (privacy == IEEE80211_PRIVACY_OFF && bss_privacy)) 938 continue; 939 if (channel && bss->pub.channel != channel) 940 continue; 941 if (!is_valid_ether_addr(bss->pub.bssid)) 942 continue; 943 /* Don't get expired BSS structs */ 944 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) && 945 !atomic_read(&bss->hold)) 946 continue; 947 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) { 948 res = bss; 949 bss_ref_get(rdev, res); 950 break; 951 } 952 } 953 954 spin_unlock_bh(&rdev->bss_lock); 955 if (!res) 956 return NULL; 957 trace_cfg80211_return_bss(&res->pub); 958 return &res->pub; 959 } 960 EXPORT_SYMBOL(cfg80211_get_bss); 961 962 static void rb_insert_bss(struct cfg80211_registered_device *rdev, 963 struct cfg80211_internal_bss *bss) 964 { 965 struct rb_node **p = &rdev->bss_tree.rb_node; 966 struct rb_node *parent = NULL; 967 struct cfg80211_internal_bss *tbss; 968 int cmp; 969 970 while (*p) { 971 parent = *p; 972 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn); 973 974 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR); 975 976 if (WARN_ON(!cmp)) { 977 /* will sort of leak this BSS */ 978 return; 979 } 980 981 if (cmp < 0) 982 p = &(*p)->rb_left; 983 else 984 p = &(*p)->rb_right; 985 } 986 987 rb_link_node(&bss->rbn, parent, p); 988 rb_insert_color(&bss->rbn, &rdev->bss_tree); 989 } 990 991 static struct cfg80211_internal_bss * 992 rb_find_bss(struct cfg80211_registered_device *rdev, 993 struct cfg80211_internal_bss *res, 994 enum bss_compare_mode mode) 995 { 996 struct rb_node *n = rdev->bss_tree.rb_node; 997 struct cfg80211_internal_bss *bss; 998 int r; 999 1000 while (n) { 1001 bss = rb_entry(n, struct cfg80211_internal_bss, rbn); 1002 r = cmp_bss(&res->pub, &bss->pub, mode); 1003 1004 if (r == 0) 1005 return bss; 1006 else if (r < 0) 1007 n = n->rb_left; 1008 else 1009 n = n->rb_right; 1010 } 1011 1012 return NULL; 1013 } 1014 1015 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev, 1016 struct cfg80211_internal_bss *new) 1017 { 1018 const struct cfg80211_bss_ies *ies; 1019 struct cfg80211_internal_bss *bss; 1020 const u8 *ie; 1021 int i, ssidlen; 1022 u8 fold = 0; 1023 u32 n_entries = 0; 1024 1025 ies = rcu_access_pointer(new->pub.beacon_ies); 1026 if (WARN_ON(!ies)) 1027 return false; 1028 1029 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 1030 if (!ie) { 1031 /* nothing to do */ 1032 return true; 1033 } 1034 1035 ssidlen = ie[1]; 1036 for (i = 0; i < ssidlen; i++) 1037 fold |= ie[2 + i]; 1038 1039 if (fold) { 1040 /* not a hidden SSID */ 1041 return true; 1042 } 1043 1044 /* This is the bad part ... */ 1045 1046 list_for_each_entry(bss, &rdev->bss_list, list) { 1047 /* 1048 * we're iterating all the entries anyway, so take the 1049 * opportunity to validate the list length accounting 1050 */ 1051 n_entries++; 1052 1053 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid)) 1054 continue; 1055 if (bss->pub.channel != new->pub.channel) 1056 continue; 1057 if (bss->pub.scan_width != new->pub.scan_width) 1058 continue; 1059 if (rcu_access_pointer(bss->pub.beacon_ies)) 1060 continue; 1061 ies = rcu_access_pointer(bss->pub.ies); 1062 if (!ies) 1063 continue; 1064 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 1065 if (!ie) 1066 continue; 1067 if (ssidlen && ie[1] != ssidlen) 1068 continue; 1069 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss)) 1070 continue; 1071 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list))) 1072 list_del(&bss->hidden_list); 1073 /* combine them */ 1074 list_add(&bss->hidden_list, &new->hidden_list); 1075 bss->pub.hidden_beacon_bss = &new->pub; 1076 new->refcount += bss->refcount; 1077 rcu_assign_pointer(bss->pub.beacon_ies, 1078 new->pub.beacon_ies); 1079 } 1080 1081 WARN_ONCE(n_entries != rdev->bss_entries, 1082 "rdev bss entries[%d]/list[len:%d] corruption\n", 1083 rdev->bss_entries, n_entries); 1084 1085 return true; 1086 } 1087 1088 struct cfg80211_non_tx_bss { 1089 struct cfg80211_bss *tx_bss; 1090 u8 max_bssid_indicator; 1091 u8 bssid_index; 1092 }; 1093 1094 /* Returned bss is reference counted and must be cleaned up appropriately. */ 1095 static struct cfg80211_internal_bss * 1096 cfg80211_bss_update(struct cfg80211_registered_device *rdev, 1097 struct cfg80211_internal_bss *tmp, 1098 bool signal_valid) 1099 { 1100 struct cfg80211_internal_bss *found = NULL; 1101 1102 if (WARN_ON(!tmp->pub.channel)) 1103 return NULL; 1104 1105 tmp->ts = jiffies; 1106 1107 spin_lock_bh(&rdev->bss_lock); 1108 1109 if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) { 1110 spin_unlock_bh(&rdev->bss_lock); 1111 return NULL; 1112 } 1113 1114 found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR); 1115 1116 if (found) { 1117 /* Update IEs */ 1118 if (rcu_access_pointer(tmp->pub.proberesp_ies)) { 1119 const struct cfg80211_bss_ies *old; 1120 1121 old = rcu_access_pointer(found->pub.proberesp_ies); 1122 1123 rcu_assign_pointer(found->pub.proberesp_ies, 1124 tmp->pub.proberesp_ies); 1125 /* Override possible earlier Beacon frame IEs */ 1126 rcu_assign_pointer(found->pub.ies, 1127 tmp->pub.proberesp_ies); 1128 if (old) 1129 kfree_rcu((struct cfg80211_bss_ies *)old, 1130 rcu_head); 1131 } else if (rcu_access_pointer(tmp->pub.beacon_ies)) { 1132 const struct cfg80211_bss_ies *old; 1133 struct cfg80211_internal_bss *bss; 1134 1135 if (found->pub.hidden_beacon_bss && 1136 !list_empty(&found->hidden_list)) { 1137 const struct cfg80211_bss_ies *f; 1138 1139 /* 1140 * The found BSS struct is one of the probe 1141 * response members of a group, but we're 1142 * receiving a beacon (beacon_ies in the tmp 1143 * bss is used). This can only mean that the 1144 * AP changed its beacon from not having an 1145 * SSID to showing it, which is confusing so 1146 * drop this information. 1147 */ 1148 1149 f = rcu_access_pointer(tmp->pub.beacon_ies); 1150 kfree_rcu((struct cfg80211_bss_ies *)f, 1151 rcu_head); 1152 goto drop; 1153 } 1154 1155 old = rcu_access_pointer(found->pub.beacon_ies); 1156 1157 rcu_assign_pointer(found->pub.beacon_ies, 1158 tmp->pub.beacon_ies); 1159 1160 /* Override IEs if they were from a beacon before */ 1161 if (old == rcu_access_pointer(found->pub.ies)) 1162 rcu_assign_pointer(found->pub.ies, 1163 tmp->pub.beacon_ies); 1164 1165 /* Assign beacon IEs to all sub entries */ 1166 list_for_each_entry(bss, &found->hidden_list, 1167 hidden_list) { 1168 const struct cfg80211_bss_ies *ies; 1169 1170 ies = rcu_access_pointer(bss->pub.beacon_ies); 1171 WARN_ON(ies != old); 1172 1173 rcu_assign_pointer(bss->pub.beacon_ies, 1174 tmp->pub.beacon_ies); 1175 } 1176 1177 if (old) 1178 kfree_rcu((struct cfg80211_bss_ies *)old, 1179 rcu_head); 1180 } 1181 1182 found->pub.beacon_interval = tmp->pub.beacon_interval; 1183 /* 1184 * don't update the signal if beacon was heard on 1185 * adjacent channel. 1186 */ 1187 if (signal_valid) 1188 found->pub.signal = tmp->pub.signal; 1189 found->pub.capability = tmp->pub.capability; 1190 found->ts = tmp->ts; 1191 found->ts_boottime = tmp->ts_boottime; 1192 found->parent_tsf = tmp->parent_tsf; 1193 found->pub.chains = tmp->pub.chains; 1194 memcpy(found->pub.chain_signal, tmp->pub.chain_signal, 1195 IEEE80211_MAX_CHAINS); 1196 ether_addr_copy(found->parent_bssid, tmp->parent_bssid); 1197 found->pub.max_bssid_indicator = tmp->pub.max_bssid_indicator; 1198 found->pub.bssid_index = tmp->pub.bssid_index; 1199 } else { 1200 struct cfg80211_internal_bss *new; 1201 struct cfg80211_internal_bss *hidden; 1202 struct cfg80211_bss_ies *ies; 1203 1204 /* 1205 * create a copy -- the "res" variable that is passed in 1206 * is allocated on the stack since it's not needed in the 1207 * more common case of an update 1208 */ 1209 new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size, 1210 GFP_ATOMIC); 1211 if (!new) { 1212 ies = (void *)rcu_dereference(tmp->pub.beacon_ies); 1213 if (ies) 1214 kfree_rcu(ies, rcu_head); 1215 ies = (void *)rcu_dereference(tmp->pub.proberesp_ies); 1216 if (ies) 1217 kfree_rcu(ies, rcu_head); 1218 goto drop; 1219 } 1220 memcpy(new, tmp, sizeof(*new)); 1221 new->refcount = 1; 1222 INIT_LIST_HEAD(&new->hidden_list); 1223 INIT_LIST_HEAD(&new->pub.nontrans_list); 1224 1225 if (rcu_access_pointer(tmp->pub.proberesp_ies)) { 1226 hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN); 1227 if (!hidden) 1228 hidden = rb_find_bss(rdev, tmp, 1229 BSS_CMP_HIDE_NUL); 1230 if (hidden) { 1231 new->pub.hidden_beacon_bss = &hidden->pub; 1232 list_add(&new->hidden_list, 1233 &hidden->hidden_list); 1234 hidden->refcount++; 1235 rcu_assign_pointer(new->pub.beacon_ies, 1236 hidden->pub.beacon_ies); 1237 } 1238 } else { 1239 /* 1240 * Ok so we found a beacon, and don't have an entry. If 1241 * it's a beacon with hidden SSID, we might be in for an 1242 * expensive search for any probe responses that should 1243 * be grouped with this beacon for updates ... 1244 */ 1245 if (!cfg80211_combine_bsses(rdev, new)) { 1246 kfree(new); 1247 goto drop; 1248 } 1249 } 1250 1251 if (rdev->bss_entries >= bss_entries_limit && 1252 !cfg80211_bss_expire_oldest(rdev)) { 1253 kfree(new); 1254 goto drop; 1255 } 1256 1257 /* This must be before the call to bss_ref_get */ 1258 if (tmp->pub.transmitted_bss) { 1259 struct cfg80211_internal_bss *pbss = 1260 container_of(tmp->pub.transmitted_bss, 1261 struct cfg80211_internal_bss, 1262 pub); 1263 1264 new->pub.transmitted_bss = tmp->pub.transmitted_bss; 1265 bss_ref_get(rdev, pbss); 1266 } 1267 1268 list_add_tail(&new->list, &rdev->bss_list); 1269 rdev->bss_entries++; 1270 rb_insert_bss(rdev, new); 1271 found = new; 1272 } 1273 1274 rdev->bss_generation++; 1275 bss_ref_get(rdev, found); 1276 spin_unlock_bh(&rdev->bss_lock); 1277 1278 return found; 1279 drop: 1280 spin_unlock_bh(&rdev->bss_lock); 1281 return NULL; 1282 } 1283 1284 /* 1285 * Update RX channel information based on the available frame payload 1286 * information. This is mainly for the 2.4 GHz band where frames can be received 1287 * from neighboring channels and the Beacon frames use the DSSS Parameter Set 1288 * element to indicate the current (transmitting) channel, but this might also 1289 * be needed on other bands if RX frequency does not match with the actual 1290 * operating channel of a BSS. 1291 */ 1292 static struct ieee80211_channel * 1293 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen, 1294 struct ieee80211_channel *channel, 1295 enum nl80211_bss_scan_width scan_width) 1296 { 1297 const u8 *tmp; 1298 u32 freq; 1299 int channel_number = -1; 1300 struct ieee80211_channel *alt_channel; 1301 1302 tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen); 1303 if (tmp && tmp[1] == 1) { 1304 channel_number = tmp[2]; 1305 } else { 1306 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen); 1307 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) { 1308 struct ieee80211_ht_operation *htop = (void *)(tmp + 2); 1309 1310 channel_number = htop->primary_chan; 1311 } 1312 } 1313 1314 if (channel_number < 0) { 1315 /* No channel information in frame payload */ 1316 return channel; 1317 } 1318 1319 freq = ieee80211_channel_to_frequency(channel_number, channel->band); 1320 alt_channel = ieee80211_get_channel(wiphy, freq); 1321 if (!alt_channel) { 1322 if (channel->band == NL80211_BAND_2GHZ) { 1323 /* 1324 * Better not allow unexpected channels when that could 1325 * be going beyond the 1-11 range (e.g., discovering 1326 * BSS on channel 12 when radio is configured for 1327 * channel 11. 1328 */ 1329 return NULL; 1330 } 1331 1332 /* No match for the payload channel number - ignore it */ 1333 return channel; 1334 } 1335 1336 if (scan_width == NL80211_BSS_CHAN_WIDTH_10 || 1337 scan_width == NL80211_BSS_CHAN_WIDTH_5) { 1338 /* 1339 * Ignore channel number in 5 and 10 MHz channels where there 1340 * may not be an n:1 or 1:n mapping between frequencies and 1341 * channel numbers. 1342 */ 1343 return channel; 1344 } 1345 1346 /* 1347 * Use the channel determined through the payload channel number 1348 * instead of the RX channel reported by the driver. 1349 */ 1350 if (alt_channel->flags & IEEE80211_CHAN_DISABLED) 1351 return NULL; 1352 return alt_channel; 1353 } 1354 1355 /* Returned bss is reference counted and must be cleaned up appropriately. */ 1356 static struct cfg80211_bss * 1357 cfg80211_inform_single_bss_data(struct wiphy *wiphy, 1358 struct cfg80211_inform_bss *data, 1359 enum cfg80211_bss_frame_type ftype, 1360 const u8 *bssid, u64 tsf, u16 capability, 1361 u16 beacon_interval, const u8 *ie, size_t ielen, 1362 struct cfg80211_non_tx_bss *non_tx_data, 1363 gfp_t gfp) 1364 { 1365 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1366 struct cfg80211_bss_ies *ies; 1367 struct ieee80211_channel *channel; 1368 struct cfg80211_internal_bss tmp = {}, *res; 1369 int bss_type; 1370 bool signal_valid; 1371 1372 if (WARN_ON(!wiphy)) 1373 return NULL; 1374 1375 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC && 1376 (data->signal < 0 || data->signal > 100))) 1377 return NULL; 1378 1379 channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan, 1380 data->scan_width); 1381 if (!channel) 1382 return NULL; 1383 1384 memcpy(tmp.pub.bssid, bssid, ETH_ALEN); 1385 tmp.pub.channel = channel; 1386 tmp.pub.scan_width = data->scan_width; 1387 tmp.pub.signal = data->signal; 1388 tmp.pub.beacon_interval = beacon_interval; 1389 tmp.pub.capability = capability; 1390 tmp.ts_boottime = data->boottime_ns; 1391 if (non_tx_data) { 1392 tmp.pub.transmitted_bss = non_tx_data->tx_bss; 1393 tmp.pub.bssid_index = non_tx_data->bssid_index; 1394 tmp.pub.max_bssid_indicator = non_tx_data->max_bssid_indicator; 1395 } 1396 1397 /* 1398 * If we do not know here whether the IEs are from a Beacon or Probe 1399 * Response frame, we need to pick one of the options and only use it 1400 * with the driver that does not provide the full Beacon/Probe Response 1401 * frame. Use Beacon frame pointer to avoid indicating that this should 1402 * override the IEs pointer should we have received an earlier 1403 * indication of Probe Response data. 1404 */ 1405 ies = kzalloc(sizeof(*ies) + ielen, gfp); 1406 if (!ies) 1407 return NULL; 1408 ies->len = ielen; 1409 ies->tsf = tsf; 1410 ies->from_beacon = false; 1411 memcpy(ies->data, ie, ielen); 1412 1413 switch (ftype) { 1414 case CFG80211_BSS_FTYPE_BEACON: 1415 ies->from_beacon = true; 1416 /* fall through */ 1417 case CFG80211_BSS_FTYPE_UNKNOWN: 1418 rcu_assign_pointer(tmp.pub.beacon_ies, ies); 1419 break; 1420 case CFG80211_BSS_FTYPE_PRESP: 1421 rcu_assign_pointer(tmp.pub.proberesp_ies, ies); 1422 break; 1423 } 1424 rcu_assign_pointer(tmp.pub.ies, ies); 1425 1426 signal_valid = abs(data->chan->center_freq - channel->center_freq) <= 1427 wiphy->max_adj_channel_rssi_comp; 1428 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid); 1429 if (!res) 1430 return NULL; 1431 1432 if (channel->band == NL80211_BAND_60GHZ) { 1433 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK; 1434 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP || 1435 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS) 1436 regulatory_hint_found_beacon(wiphy, channel, gfp); 1437 } else { 1438 if (res->pub.capability & WLAN_CAPABILITY_ESS) 1439 regulatory_hint_found_beacon(wiphy, channel, gfp); 1440 } 1441 1442 if (non_tx_data && non_tx_data->tx_bss) { 1443 /* this is a nontransmitting bss, we need to add it to 1444 * transmitting bss' list if it is not there 1445 */ 1446 if (cfg80211_add_nontrans_list(non_tx_data->tx_bss, 1447 &res->pub)) { 1448 if (__cfg80211_unlink_bss(rdev, res)) 1449 rdev->bss_generation++; 1450 } 1451 } 1452 1453 trace_cfg80211_return_bss(&res->pub); 1454 /* cfg80211_bss_update gives us a referenced result */ 1455 return &res->pub; 1456 } 1457 1458 static const struct element 1459 *cfg80211_get_profile_continuation(const u8 *ie, size_t ielen, 1460 const struct element *mbssid_elem, 1461 const struct element *sub_elem) 1462 { 1463 const u8 *mbssid_end = mbssid_elem->data + mbssid_elem->datalen; 1464 const struct element *next_mbssid; 1465 const struct element *next_sub; 1466 1467 next_mbssid = cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID, 1468 mbssid_end, 1469 ielen - (mbssid_end - ie)); 1470 1471 /* 1472 * If is is not the last subelement in current MBSSID IE or there isn't 1473 * a next MBSSID IE - profile is complete. 1474 */ 1475 if ((sub_elem->data + sub_elem->datalen < mbssid_end - 1) || 1476 !next_mbssid) 1477 return NULL; 1478 1479 /* For any length error, just return NULL */ 1480 1481 if (next_mbssid->datalen < 4) 1482 return NULL; 1483 1484 next_sub = (void *)&next_mbssid->data[1]; 1485 1486 if (next_mbssid->data + next_mbssid->datalen < 1487 next_sub->data + next_sub->datalen) 1488 return NULL; 1489 1490 if (next_sub->id != 0 || next_sub->datalen < 2) 1491 return NULL; 1492 1493 /* 1494 * Check if the first element in the next sub element is a start 1495 * of a new profile 1496 */ 1497 return next_sub->data[0] == WLAN_EID_NON_TX_BSSID_CAP ? 1498 NULL : next_mbssid; 1499 } 1500 1501 size_t cfg80211_merge_profile(const u8 *ie, size_t ielen, 1502 const struct element *mbssid_elem, 1503 const struct element *sub_elem, 1504 u8 *merged_ie, size_t max_copy_len) 1505 { 1506 size_t copied_len = sub_elem->datalen; 1507 const struct element *next_mbssid; 1508 1509 if (sub_elem->datalen > max_copy_len) 1510 return 0; 1511 1512 memcpy(merged_ie, sub_elem->data, sub_elem->datalen); 1513 1514 while ((next_mbssid = cfg80211_get_profile_continuation(ie, ielen, 1515 mbssid_elem, 1516 sub_elem))) { 1517 const struct element *next_sub = (void *)&next_mbssid->data[1]; 1518 1519 if (copied_len + next_sub->datalen > max_copy_len) 1520 break; 1521 memcpy(merged_ie + copied_len, next_sub->data, 1522 next_sub->datalen); 1523 copied_len += next_sub->datalen; 1524 } 1525 1526 return copied_len; 1527 } 1528 EXPORT_SYMBOL(cfg80211_merge_profile); 1529 1530 static void cfg80211_parse_mbssid_data(struct wiphy *wiphy, 1531 struct cfg80211_inform_bss *data, 1532 enum cfg80211_bss_frame_type ftype, 1533 const u8 *bssid, u64 tsf, 1534 u16 beacon_interval, const u8 *ie, 1535 size_t ielen, 1536 struct cfg80211_non_tx_bss *non_tx_data, 1537 gfp_t gfp) 1538 { 1539 const u8 *mbssid_index_ie; 1540 const struct element *elem, *sub; 1541 size_t new_ie_len; 1542 u8 new_bssid[ETH_ALEN]; 1543 u8 *new_ie, *profile; 1544 u64 seen_indices = 0; 1545 u16 capability; 1546 struct cfg80211_bss *bss; 1547 1548 if (!non_tx_data) 1549 return; 1550 if (!cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen)) 1551 return; 1552 if (!wiphy->support_mbssid) 1553 return; 1554 if (wiphy->support_only_he_mbssid && 1555 !cfg80211_find_ext_ie(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen)) 1556 return; 1557 1558 new_ie = kmalloc(IEEE80211_MAX_DATA_LEN, gfp); 1559 if (!new_ie) 1560 return; 1561 1562 profile = kmalloc(ielen, gfp); 1563 if (!profile) 1564 goto out; 1565 1566 for_each_element_id(elem, WLAN_EID_MULTIPLE_BSSID, ie, ielen) { 1567 if (elem->datalen < 4) 1568 continue; 1569 for_each_element(sub, elem->data + 1, elem->datalen - 1) { 1570 u8 profile_len; 1571 1572 if (sub->id != 0 || sub->datalen < 4) { 1573 /* not a valid BSS profile */ 1574 continue; 1575 } 1576 1577 if (sub->data[0] != WLAN_EID_NON_TX_BSSID_CAP || 1578 sub->data[1] != 2) { 1579 /* The first element within the Nontransmitted 1580 * BSSID Profile is not the Nontransmitted 1581 * BSSID Capability element. 1582 */ 1583 continue; 1584 } 1585 1586 memset(profile, 0, ielen); 1587 profile_len = cfg80211_merge_profile(ie, ielen, 1588 elem, 1589 sub, 1590 profile, 1591 ielen); 1592 1593 /* found a Nontransmitted BSSID Profile */ 1594 mbssid_index_ie = cfg80211_find_ie 1595 (WLAN_EID_MULTI_BSSID_IDX, 1596 profile, profile_len); 1597 if (!mbssid_index_ie || mbssid_index_ie[1] < 1 || 1598 mbssid_index_ie[2] == 0 || 1599 mbssid_index_ie[2] > 46) { 1600 /* No valid Multiple BSSID-Index element */ 1601 continue; 1602 } 1603 1604 if (seen_indices & BIT(mbssid_index_ie[2])) 1605 /* We don't support legacy split of a profile */ 1606 net_dbg_ratelimited("Partial info for BSSID index %d\n", 1607 mbssid_index_ie[2]); 1608 1609 seen_indices |= BIT(mbssid_index_ie[2]); 1610 1611 non_tx_data->bssid_index = mbssid_index_ie[2]; 1612 non_tx_data->max_bssid_indicator = elem->data[0]; 1613 1614 cfg80211_gen_new_bssid(bssid, 1615 non_tx_data->max_bssid_indicator, 1616 non_tx_data->bssid_index, 1617 new_bssid); 1618 memset(new_ie, 0, IEEE80211_MAX_DATA_LEN); 1619 new_ie_len = cfg80211_gen_new_ie(ie, ielen, 1620 profile, 1621 profile_len, new_ie, 1622 gfp); 1623 if (!new_ie_len) 1624 continue; 1625 1626 capability = get_unaligned_le16(profile + 2); 1627 bss = cfg80211_inform_single_bss_data(wiphy, data, 1628 ftype, 1629 new_bssid, tsf, 1630 capability, 1631 beacon_interval, 1632 new_ie, 1633 new_ie_len, 1634 non_tx_data, 1635 gfp); 1636 if (!bss) 1637 break; 1638 cfg80211_put_bss(wiphy, bss); 1639 } 1640 } 1641 1642 out: 1643 kfree(new_ie); 1644 kfree(profile); 1645 } 1646 1647 struct cfg80211_bss * 1648 cfg80211_inform_bss_data(struct wiphy *wiphy, 1649 struct cfg80211_inform_bss *data, 1650 enum cfg80211_bss_frame_type ftype, 1651 const u8 *bssid, u64 tsf, u16 capability, 1652 u16 beacon_interval, const u8 *ie, size_t ielen, 1653 gfp_t gfp) 1654 { 1655 struct cfg80211_bss *res; 1656 struct cfg80211_non_tx_bss non_tx_data; 1657 1658 res = cfg80211_inform_single_bss_data(wiphy, data, ftype, bssid, tsf, 1659 capability, beacon_interval, ie, 1660 ielen, NULL, gfp); 1661 non_tx_data.tx_bss = res; 1662 cfg80211_parse_mbssid_data(wiphy, data, ftype, bssid, tsf, 1663 beacon_interval, ie, ielen, &non_tx_data, 1664 gfp); 1665 return res; 1666 } 1667 EXPORT_SYMBOL(cfg80211_inform_bss_data); 1668 1669 static void 1670 cfg80211_parse_mbssid_frame_data(struct wiphy *wiphy, 1671 struct cfg80211_inform_bss *data, 1672 struct ieee80211_mgmt *mgmt, size_t len, 1673 struct cfg80211_non_tx_bss *non_tx_data, 1674 gfp_t gfp) 1675 { 1676 enum cfg80211_bss_frame_type ftype; 1677 const u8 *ie = mgmt->u.probe_resp.variable; 1678 size_t ielen = len - offsetof(struct ieee80211_mgmt, 1679 u.probe_resp.variable); 1680 1681 ftype = ieee80211_is_beacon(mgmt->frame_control) ? 1682 CFG80211_BSS_FTYPE_BEACON : CFG80211_BSS_FTYPE_PRESP; 1683 1684 cfg80211_parse_mbssid_data(wiphy, data, ftype, mgmt->bssid, 1685 le64_to_cpu(mgmt->u.probe_resp.timestamp), 1686 le16_to_cpu(mgmt->u.probe_resp.beacon_int), 1687 ie, ielen, non_tx_data, gfp); 1688 } 1689 1690 static void 1691 cfg80211_update_notlisted_nontrans(struct wiphy *wiphy, 1692 struct cfg80211_bss *nontrans_bss, 1693 struct ieee80211_mgmt *mgmt, size_t len, 1694 gfp_t gfp) 1695 { 1696 u8 *ie, *new_ie, *pos; 1697 const u8 *nontrans_ssid, *trans_ssid, *mbssid; 1698 size_t ielen = len - offsetof(struct ieee80211_mgmt, 1699 u.probe_resp.variable); 1700 size_t new_ie_len; 1701 struct cfg80211_bss_ies *new_ies; 1702 const struct cfg80211_bss_ies *old; 1703 u8 cpy_len; 1704 1705 ie = mgmt->u.probe_resp.variable; 1706 1707 new_ie_len = ielen; 1708 trans_ssid = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen); 1709 if (!trans_ssid) 1710 return; 1711 new_ie_len -= trans_ssid[1]; 1712 mbssid = cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen); 1713 if (!mbssid) 1714 return; 1715 new_ie_len -= mbssid[1]; 1716 rcu_read_lock(); 1717 nontrans_ssid = ieee80211_bss_get_ie(nontrans_bss, WLAN_EID_SSID); 1718 if (!nontrans_ssid) { 1719 rcu_read_unlock(); 1720 return; 1721 } 1722 new_ie_len += nontrans_ssid[1]; 1723 rcu_read_unlock(); 1724 1725 /* generate new ie for nontrans BSS 1726 * 1. replace SSID with nontrans BSS' SSID 1727 * 2. skip MBSSID IE 1728 */ 1729 new_ie = kzalloc(new_ie_len, gfp); 1730 if (!new_ie) 1731 return; 1732 new_ies = kzalloc(sizeof(*new_ies) + new_ie_len, gfp); 1733 if (!new_ies) 1734 goto out_free; 1735 1736 pos = new_ie; 1737 1738 /* copy the nontransmitted SSID */ 1739 cpy_len = nontrans_ssid[1] + 2; 1740 memcpy(pos, nontrans_ssid, cpy_len); 1741 pos += cpy_len; 1742 /* copy the IEs between SSID and MBSSID */ 1743 cpy_len = trans_ssid[1] + 2; 1744 memcpy(pos, (trans_ssid + cpy_len), (mbssid - (trans_ssid + cpy_len))); 1745 pos += (mbssid - (trans_ssid + cpy_len)); 1746 /* copy the IEs after MBSSID */ 1747 cpy_len = mbssid[1] + 2; 1748 memcpy(pos, mbssid + cpy_len, ((ie + ielen) - (mbssid + cpy_len))); 1749 1750 /* update ie */ 1751 new_ies->len = new_ie_len; 1752 new_ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp); 1753 new_ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control); 1754 memcpy(new_ies->data, new_ie, new_ie_len); 1755 if (ieee80211_is_probe_resp(mgmt->frame_control)) { 1756 old = rcu_access_pointer(nontrans_bss->proberesp_ies); 1757 rcu_assign_pointer(nontrans_bss->proberesp_ies, new_ies); 1758 rcu_assign_pointer(nontrans_bss->ies, new_ies); 1759 if (old) 1760 kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head); 1761 } else { 1762 old = rcu_access_pointer(nontrans_bss->beacon_ies); 1763 rcu_assign_pointer(nontrans_bss->beacon_ies, new_ies); 1764 rcu_assign_pointer(nontrans_bss->ies, new_ies); 1765 if (old) 1766 kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head); 1767 } 1768 1769 out_free: 1770 kfree(new_ie); 1771 } 1772 1773 /* cfg80211_inform_bss_width_frame helper */ 1774 static struct cfg80211_bss * 1775 cfg80211_inform_single_bss_frame_data(struct wiphy *wiphy, 1776 struct cfg80211_inform_bss *data, 1777 struct ieee80211_mgmt *mgmt, size_t len, 1778 struct cfg80211_non_tx_bss *non_tx_data, 1779 gfp_t gfp) 1780 { 1781 struct cfg80211_internal_bss tmp = {}, *res; 1782 struct cfg80211_bss_ies *ies; 1783 struct ieee80211_channel *channel; 1784 bool signal_valid; 1785 size_t ielen = len - offsetof(struct ieee80211_mgmt, 1786 u.probe_resp.variable); 1787 int bss_type; 1788 1789 BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) != 1790 offsetof(struct ieee80211_mgmt, u.beacon.variable)); 1791 1792 trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len); 1793 1794 if (WARN_ON(!mgmt)) 1795 return NULL; 1796 1797 if (WARN_ON(!wiphy)) 1798 return NULL; 1799 1800 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC && 1801 (data->signal < 0 || data->signal > 100))) 1802 return NULL; 1803 1804 if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable))) 1805 return NULL; 1806 1807 channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable, 1808 ielen, data->chan, data->scan_width); 1809 if (!channel) 1810 return NULL; 1811 1812 ies = kzalloc(sizeof(*ies) + ielen, gfp); 1813 if (!ies) 1814 return NULL; 1815 ies->len = ielen; 1816 ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp); 1817 ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control); 1818 memcpy(ies->data, mgmt->u.probe_resp.variable, ielen); 1819 1820 if (ieee80211_is_probe_resp(mgmt->frame_control)) 1821 rcu_assign_pointer(tmp.pub.proberesp_ies, ies); 1822 else 1823 rcu_assign_pointer(tmp.pub.beacon_ies, ies); 1824 rcu_assign_pointer(tmp.pub.ies, ies); 1825 1826 memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN); 1827 tmp.pub.channel = channel; 1828 tmp.pub.scan_width = data->scan_width; 1829 tmp.pub.signal = data->signal; 1830 tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int); 1831 tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info); 1832 tmp.ts_boottime = data->boottime_ns; 1833 tmp.parent_tsf = data->parent_tsf; 1834 tmp.pub.chains = data->chains; 1835 memcpy(tmp.pub.chain_signal, data->chain_signal, IEEE80211_MAX_CHAINS); 1836 ether_addr_copy(tmp.parent_bssid, data->parent_bssid); 1837 if (non_tx_data) { 1838 tmp.pub.transmitted_bss = non_tx_data->tx_bss; 1839 tmp.pub.bssid_index = non_tx_data->bssid_index; 1840 tmp.pub.max_bssid_indicator = non_tx_data->max_bssid_indicator; 1841 } 1842 1843 signal_valid = abs(data->chan->center_freq - channel->center_freq) <= 1844 wiphy->max_adj_channel_rssi_comp; 1845 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid); 1846 if (!res) 1847 return NULL; 1848 1849 if (channel->band == NL80211_BAND_60GHZ) { 1850 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK; 1851 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP || 1852 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS) 1853 regulatory_hint_found_beacon(wiphy, channel, gfp); 1854 } else { 1855 if (res->pub.capability & WLAN_CAPABILITY_ESS) 1856 regulatory_hint_found_beacon(wiphy, channel, gfp); 1857 } 1858 1859 trace_cfg80211_return_bss(&res->pub); 1860 /* cfg80211_bss_update gives us a referenced result */ 1861 return &res->pub; 1862 } 1863 1864 struct cfg80211_bss * 1865 cfg80211_inform_bss_frame_data(struct wiphy *wiphy, 1866 struct cfg80211_inform_bss *data, 1867 struct ieee80211_mgmt *mgmt, size_t len, 1868 gfp_t gfp) 1869 { 1870 struct cfg80211_bss *res, *tmp_bss; 1871 const u8 *ie = mgmt->u.probe_resp.variable; 1872 const struct cfg80211_bss_ies *ies1, *ies2; 1873 size_t ielen = len - offsetof(struct ieee80211_mgmt, 1874 u.probe_resp.variable); 1875 struct cfg80211_non_tx_bss non_tx_data; 1876 1877 res = cfg80211_inform_single_bss_frame_data(wiphy, data, mgmt, 1878 len, NULL, gfp); 1879 if (!res || !wiphy->support_mbssid || 1880 !cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen)) 1881 return res; 1882 if (wiphy->support_only_he_mbssid && 1883 !cfg80211_find_ext_ie(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen)) 1884 return res; 1885 1886 non_tx_data.tx_bss = res; 1887 /* process each non-transmitting bss */ 1888 cfg80211_parse_mbssid_frame_data(wiphy, data, mgmt, len, 1889 &non_tx_data, gfp); 1890 1891 /* check if the res has other nontransmitting bss which is not 1892 * in MBSSID IE 1893 */ 1894 ies1 = rcu_access_pointer(res->ies); 1895 1896 /* go through nontrans_list, if the timestamp of the BSS is 1897 * earlier than the timestamp of the transmitting BSS then 1898 * update it 1899 */ 1900 list_for_each_entry(tmp_bss, &res->nontrans_list, 1901 nontrans_list) { 1902 ies2 = rcu_access_pointer(tmp_bss->ies); 1903 if (ies2->tsf < ies1->tsf) 1904 cfg80211_update_notlisted_nontrans(wiphy, tmp_bss, 1905 mgmt, len, gfp); 1906 } 1907 1908 return res; 1909 } 1910 EXPORT_SYMBOL(cfg80211_inform_bss_frame_data); 1911 1912 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 1913 { 1914 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1915 struct cfg80211_internal_bss *bss; 1916 1917 if (!pub) 1918 return; 1919 1920 bss = container_of(pub, struct cfg80211_internal_bss, pub); 1921 1922 spin_lock_bh(&rdev->bss_lock); 1923 bss_ref_get(rdev, bss); 1924 spin_unlock_bh(&rdev->bss_lock); 1925 } 1926 EXPORT_SYMBOL(cfg80211_ref_bss); 1927 1928 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 1929 { 1930 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1931 struct cfg80211_internal_bss *bss; 1932 1933 if (!pub) 1934 return; 1935 1936 bss = container_of(pub, struct cfg80211_internal_bss, pub); 1937 1938 spin_lock_bh(&rdev->bss_lock); 1939 bss_ref_put(rdev, bss); 1940 spin_unlock_bh(&rdev->bss_lock); 1941 } 1942 EXPORT_SYMBOL(cfg80211_put_bss); 1943 1944 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 1945 { 1946 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1947 struct cfg80211_internal_bss *bss, *tmp1; 1948 struct cfg80211_bss *nontrans_bss, *tmp; 1949 1950 if (WARN_ON(!pub)) 1951 return; 1952 1953 bss = container_of(pub, struct cfg80211_internal_bss, pub); 1954 1955 spin_lock_bh(&rdev->bss_lock); 1956 if (list_empty(&bss->list)) 1957 goto out; 1958 1959 list_for_each_entry_safe(nontrans_bss, tmp, 1960 &pub->nontrans_list, 1961 nontrans_list) { 1962 tmp1 = container_of(nontrans_bss, 1963 struct cfg80211_internal_bss, pub); 1964 if (__cfg80211_unlink_bss(rdev, tmp1)) 1965 rdev->bss_generation++; 1966 } 1967 1968 if (__cfg80211_unlink_bss(rdev, bss)) 1969 rdev->bss_generation++; 1970 out: 1971 spin_unlock_bh(&rdev->bss_lock); 1972 } 1973 EXPORT_SYMBOL(cfg80211_unlink_bss); 1974 1975 #ifdef CONFIG_CFG80211_WEXT 1976 static struct cfg80211_registered_device * 1977 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex) 1978 { 1979 struct cfg80211_registered_device *rdev; 1980 struct net_device *dev; 1981 1982 ASSERT_RTNL(); 1983 1984 dev = dev_get_by_index(net, ifindex); 1985 if (!dev) 1986 return ERR_PTR(-ENODEV); 1987 if (dev->ieee80211_ptr) 1988 rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy); 1989 else 1990 rdev = ERR_PTR(-ENODEV); 1991 dev_put(dev); 1992 return rdev; 1993 } 1994 1995 int cfg80211_wext_siwscan(struct net_device *dev, 1996 struct iw_request_info *info, 1997 union iwreq_data *wrqu, char *extra) 1998 { 1999 struct cfg80211_registered_device *rdev; 2000 struct wiphy *wiphy; 2001 struct iw_scan_req *wreq = NULL; 2002 struct cfg80211_scan_request *creq = NULL; 2003 int i, err, n_channels = 0; 2004 enum nl80211_band band; 2005 2006 if (!netif_running(dev)) 2007 return -ENETDOWN; 2008 2009 if (wrqu->data.length == sizeof(struct iw_scan_req)) 2010 wreq = (struct iw_scan_req *)extra; 2011 2012 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex); 2013 2014 if (IS_ERR(rdev)) 2015 return PTR_ERR(rdev); 2016 2017 if (rdev->scan_req || rdev->scan_msg) { 2018 err = -EBUSY; 2019 goto out; 2020 } 2021 2022 wiphy = &rdev->wiphy; 2023 2024 /* Determine number of channels, needed to allocate creq */ 2025 if (wreq && wreq->num_channels) 2026 n_channels = wreq->num_channels; 2027 else 2028 n_channels = ieee80211_get_num_supported_channels(wiphy); 2029 2030 creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) + 2031 n_channels * sizeof(void *), 2032 GFP_ATOMIC); 2033 if (!creq) { 2034 err = -ENOMEM; 2035 goto out; 2036 } 2037 2038 creq->wiphy = wiphy; 2039 creq->wdev = dev->ieee80211_ptr; 2040 /* SSIDs come after channels */ 2041 creq->ssids = (void *)&creq->channels[n_channels]; 2042 creq->n_channels = n_channels; 2043 creq->n_ssids = 1; 2044 creq->scan_start = jiffies; 2045 2046 /* translate "Scan on frequencies" request */ 2047 i = 0; 2048 for (band = 0; band < NUM_NL80211_BANDS; band++) { 2049 int j; 2050 2051 if (!wiphy->bands[band]) 2052 continue; 2053 2054 for (j = 0; j < wiphy->bands[band]->n_channels; j++) { 2055 /* ignore disabled channels */ 2056 if (wiphy->bands[band]->channels[j].flags & 2057 IEEE80211_CHAN_DISABLED) 2058 continue; 2059 2060 /* If we have a wireless request structure and the 2061 * wireless request specifies frequencies, then search 2062 * for the matching hardware channel. 2063 */ 2064 if (wreq && wreq->num_channels) { 2065 int k; 2066 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq; 2067 for (k = 0; k < wreq->num_channels; k++) { 2068 struct iw_freq *freq = 2069 &wreq->channel_list[k]; 2070 int wext_freq = 2071 cfg80211_wext_freq(freq); 2072 2073 if (wext_freq == wiphy_freq) 2074 goto wext_freq_found; 2075 } 2076 goto wext_freq_not_found; 2077 } 2078 2079 wext_freq_found: 2080 creq->channels[i] = &wiphy->bands[band]->channels[j]; 2081 i++; 2082 wext_freq_not_found: ; 2083 } 2084 } 2085 /* No channels found? */ 2086 if (!i) { 2087 err = -EINVAL; 2088 goto out; 2089 } 2090 2091 /* Set real number of channels specified in creq->channels[] */ 2092 creq->n_channels = i; 2093 2094 /* translate "Scan for SSID" request */ 2095 if (wreq) { 2096 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) { 2097 if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) { 2098 err = -EINVAL; 2099 goto out; 2100 } 2101 memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len); 2102 creq->ssids[0].ssid_len = wreq->essid_len; 2103 } 2104 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE) 2105 creq->n_ssids = 0; 2106 } 2107 2108 for (i = 0; i < NUM_NL80211_BANDS; i++) 2109 if (wiphy->bands[i]) 2110 creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1; 2111 2112 eth_broadcast_addr(creq->bssid); 2113 2114 rdev->scan_req = creq; 2115 err = rdev_scan(rdev, creq); 2116 if (err) { 2117 rdev->scan_req = NULL; 2118 /* creq will be freed below */ 2119 } else { 2120 nl80211_send_scan_start(rdev, dev->ieee80211_ptr); 2121 /* creq now owned by driver */ 2122 creq = NULL; 2123 dev_hold(dev); 2124 } 2125 out: 2126 kfree(creq); 2127 return err; 2128 } 2129 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan); 2130 2131 static char *ieee80211_scan_add_ies(struct iw_request_info *info, 2132 const struct cfg80211_bss_ies *ies, 2133 char *current_ev, char *end_buf) 2134 { 2135 const u8 *pos, *end, *next; 2136 struct iw_event iwe; 2137 2138 if (!ies) 2139 return current_ev; 2140 2141 /* 2142 * If needed, fragment the IEs buffer (at IE boundaries) into short 2143 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages. 2144 */ 2145 pos = ies->data; 2146 end = pos + ies->len; 2147 2148 while (end - pos > IW_GENERIC_IE_MAX) { 2149 next = pos + 2 + pos[1]; 2150 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX) 2151 next = next + 2 + next[1]; 2152 2153 memset(&iwe, 0, sizeof(iwe)); 2154 iwe.cmd = IWEVGENIE; 2155 iwe.u.data.length = next - pos; 2156 current_ev = iwe_stream_add_point_check(info, current_ev, 2157 end_buf, &iwe, 2158 (void *)pos); 2159 if (IS_ERR(current_ev)) 2160 return current_ev; 2161 pos = next; 2162 } 2163 2164 if (end > pos) { 2165 memset(&iwe, 0, sizeof(iwe)); 2166 iwe.cmd = IWEVGENIE; 2167 iwe.u.data.length = end - pos; 2168 current_ev = iwe_stream_add_point_check(info, current_ev, 2169 end_buf, &iwe, 2170 (void *)pos); 2171 if (IS_ERR(current_ev)) 2172 return current_ev; 2173 } 2174 2175 return current_ev; 2176 } 2177 2178 static char * 2179 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info, 2180 struct cfg80211_internal_bss *bss, char *current_ev, 2181 char *end_buf) 2182 { 2183 const struct cfg80211_bss_ies *ies; 2184 struct iw_event iwe; 2185 const u8 *ie; 2186 u8 buf[50]; 2187 u8 *cfg, *p, *tmp; 2188 int rem, i, sig; 2189 bool ismesh = false; 2190 2191 memset(&iwe, 0, sizeof(iwe)); 2192 iwe.cmd = SIOCGIWAP; 2193 iwe.u.ap_addr.sa_family = ARPHRD_ETHER; 2194 memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN); 2195 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 2196 IW_EV_ADDR_LEN); 2197 if (IS_ERR(current_ev)) 2198 return current_ev; 2199 2200 memset(&iwe, 0, sizeof(iwe)); 2201 iwe.cmd = SIOCGIWFREQ; 2202 iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq); 2203 iwe.u.freq.e = 0; 2204 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 2205 IW_EV_FREQ_LEN); 2206 if (IS_ERR(current_ev)) 2207 return current_ev; 2208 2209 memset(&iwe, 0, sizeof(iwe)); 2210 iwe.cmd = SIOCGIWFREQ; 2211 iwe.u.freq.m = bss->pub.channel->center_freq; 2212 iwe.u.freq.e = 6; 2213 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 2214 IW_EV_FREQ_LEN); 2215 if (IS_ERR(current_ev)) 2216 return current_ev; 2217 2218 if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) { 2219 memset(&iwe, 0, sizeof(iwe)); 2220 iwe.cmd = IWEVQUAL; 2221 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED | 2222 IW_QUAL_NOISE_INVALID | 2223 IW_QUAL_QUAL_UPDATED; 2224 switch (wiphy->signal_type) { 2225 case CFG80211_SIGNAL_TYPE_MBM: 2226 sig = bss->pub.signal / 100; 2227 iwe.u.qual.level = sig; 2228 iwe.u.qual.updated |= IW_QUAL_DBM; 2229 if (sig < -110) /* rather bad */ 2230 sig = -110; 2231 else if (sig > -40) /* perfect */ 2232 sig = -40; 2233 /* will give a range of 0 .. 70 */ 2234 iwe.u.qual.qual = sig + 110; 2235 break; 2236 case CFG80211_SIGNAL_TYPE_UNSPEC: 2237 iwe.u.qual.level = bss->pub.signal; 2238 /* will give range 0 .. 100 */ 2239 iwe.u.qual.qual = bss->pub.signal; 2240 break; 2241 default: 2242 /* not reached */ 2243 break; 2244 } 2245 current_ev = iwe_stream_add_event_check(info, current_ev, 2246 end_buf, &iwe, 2247 IW_EV_QUAL_LEN); 2248 if (IS_ERR(current_ev)) 2249 return current_ev; 2250 } 2251 2252 memset(&iwe, 0, sizeof(iwe)); 2253 iwe.cmd = SIOCGIWENCODE; 2254 if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY) 2255 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY; 2256 else 2257 iwe.u.data.flags = IW_ENCODE_DISABLED; 2258 iwe.u.data.length = 0; 2259 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf, 2260 &iwe, ""); 2261 if (IS_ERR(current_ev)) 2262 return current_ev; 2263 2264 rcu_read_lock(); 2265 ies = rcu_dereference(bss->pub.ies); 2266 rem = ies->len; 2267 ie = ies->data; 2268 2269 while (rem >= 2) { 2270 /* invalid data */ 2271 if (ie[1] > rem - 2) 2272 break; 2273 2274 switch (ie[0]) { 2275 case WLAN_EID_SSID: 2276 memset(&iwe, 0, sizeof(iwe)); 2277 iwe.cmd = SIOCGIWESSID; 2278 iwe.u.data.length = ie[1]; 2279 iwe.u.data.flags = 1; 2280 current_ev = iwe_stream_add_point_check(info, 2281 current_ev, 2282 end_buf, &iwe, 2283 (u8 *)ie + 2); 2284 if (IS_ERR(current_ev)) 2285 goto unlock; 2286 break; 2287 case WLAN_EID_MESH_ID: 2288 memset(&iwe, 0, sizeof(iwe)); 2289 iwe.cmd = SIOCGIWESSID; 2290 iwe.u.data.length = ie[1]; 2291 iwe.u.data.flags = 1; 2292 current_ev = iwe_stream_add_point_check(info, 2293 current_ev, 2294 end_buf, &iwe, 2295 (u8 *)ie + 2); 2296 if (IS_ERR(current_ev)) 2297 goto unlock; 2298 break; 2299 case WLAN_EID_MESH_CONFIG: 2300 ismesh = true; 2301 if (ie[1] != sizeof(struct ieee80211_meshconf_ie)) 2302 break; 2303 cfg = (u8 *)ie + 2; 2304 memset(&iwe, 0, sizeof(iwe)); 2305 iwe.cmd = IWEVCUSTOM; 2306 sprintf(buf, "Mesh Network Path Selection Protocol ID: " 2307 "0x%02X", cfg[0]); 2308 iwe.u.data.length = strlen(buf); 2309 current_ev = iwe_stream_add_point_check(info, 2310 current_ev, 2311 end_buf, 2312 &iwe, buf); 2313 if (IS_ERR(current_ev)) 2314 goto unlock; 2315 sprintf(buf, "Path Selection Metric ID: 0x%02X", 2316 cfg[1]); 2317 iwe.u.data.length = strlen(buf); 2318 current_ev = iwe_stream_add_point_check(info, 2319 current_ev, 2320 end_buf, 2321 &iwe, buf); 2322 if (IS_ERR(current_ev)) 2323 goto unlock; 2324 sprintf(buf, "Congestion Control Mode ID: 0x%02X", 2325 cfg[2]); 2326 iwe.u.data.length = strlen(buf); 2327 current_ev = iwe_stream_add_point_check(info, 2328 current_ev, 2329 end_buf, 2330 &iwe, buf); 2331 if (IS_ERR(current_ev)) 2332 goto unlock; 2333 sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]); 2334 iwe.u.data.length = strlen(buf); 2335 current_ev = iwe_stream_add_point_check(info, 2336 current_ev, 2337 end_buf, 2338 &iwe, buf); 2339 if (IS_ERR(current_ev)) 2340 goto unlock; 2341 sprintf(buf, "Authentication ID: 0x%02X", cfg[4]); 2342 iwe.u.data.length = strlen(buf); 2343 current_ev = iwe_stream_add_point_check(info, 2344 current_ev, 2345 end_buf, 2346 &iwe, buf); 2347 if (IS_ERR(current_ev)) 2348 goto unlock; 2349 sprintf(buf, "Formation Info: 0x%02X", cfg[5]); 2350 iwe.u.data.length = strlen(buf); 2351 current_ev = iwe_stream_add_point_check(info, 2352 current_ev, 2353 end_buf, 2354 &iwe, buf); 2355 if (IS_ERR(current_ev)) 2356 goto unlock; 2357 sprintf(buf, "Capabilities: 0x%02X", cfg[6]); 2358 iwe.u.data.length = strlen(buf); 2359 current_ev = iwe_stream_add_point_check(info, 2360 current_ev, 2361 end_buf, 2362 &iwe, buf); 2363 if (IS_ERR(current_ev)) 2364 goto unlock; 2365 break; 2366 case WLAN_EID_SUPP_RATES: 2367 case WLAN_EID_EXT_SUPP_RATES: 2368 /* display all supported rates in readable format */ 2369 p = current_ev + iwe_stream_lcp_len(info); 2370 2371 memset(&iwe, 0, sizeof(iwe)); 2372 iwe.cmd = SIOCGIWRATE; 2373 /* Those two flags are ignored... */ 2374 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0; 2375 2376 for (i = 0; i < ie[1]; i++) { 2377 iwe.u.bitrate.value = 2378 ((ie[i + 2] & 0x7f) * 500000); 2379 tmp = p; 2380 p = iwe_stream_add_value(info, current_ev, p, 2381 end_buf, &iwe, 2382 IW_EV_PARAM_LEN); 2383 if (p == tmp) { 2384 current_ev = ERR_PTR(-E2BIG); 2385 goto unlock; 2386 } 2387 } 2388 current_ev = p; 2389 break; 2390 } 2391 rem -= ie[1] + 2; 2392 ie += ie[1] + 2; 2393 } 2394 2395 if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) || 2396 ismesh) { 2397 memset(&iwe, 0, sizeof(iwe)); 2398 iwe.cmd = SIOCGIWMODE; 2399 if (ismesh) 2400 iwe.u.mode = IW_MODE_MESH; 2401 else if (bss->pub.capability & WLAN_CAPABILITY_ESS) 2402 iwe.u.mode = IW_MODE_MASTER; 2403 else 2404 iwe.u.mode = IW_MODE_ADHOC; 2405 current_ev = iwe_stream_add_event_check(info, current_ev, 2406 end_buf, &iwe, 2407 IW_EV_UINT_LEN); 2408 if (IS_ERR(current_ev)) 2409 goto unlock; 2410 } 2411 2412 memset(&iwe, 0, sizeof(iwe)); 2413 iwe.cmd = IWEVCUSTOM; 2414 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf)); 2415 iwe.u.data.length = strlen(buf); 2416 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf, 2417 &iwe, buf); 2418 if (IS_ERR(current_ev)) 2419 goto unlock; 2420 memset(&iwe, 0, sizeof(iwe)); 2421 iwe.cmd = IWEVCUSTOM; 2422 sprintf(buf, " Last beacon: %ums ago", 2423 elapsed_jiffies_msecs(bss->ts)); 2424 iwe.u.data.length = strlen(buf); 2425 current_ev = iwe_stream_add_point_check(info, current_ev, 2426 end_buf, &iwe, buf); 2427 if (IS_ERR(current_ev)) 2428 goto unlock; 2429 2430 current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf); 2431 2432 unlock: 2433 rcu_read_unlock(); 2434 return current_ev; 2435 } 2436 2437 2438 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev, 2439 struct iw_request_info *info, 2440 char *buf, size_t len) 2441 { 2442 char *current_ev = buf; 2443 char *end_buf = buf + len; 2444 struct cfg80211_internal_bss *bss; 2445 int err = 0; 2446 2447 spin_lock_bh(&rdev->bss_lock); 2448 cfg80211_bss_expire(rdev); 2449 2450 list_for_each_entry(bss, &rdev->bss_list, list) { 2451 if (buf + len - current_ev <= IW_EV_ADDR_LEN) { 2452 err = -E2BIG; 2453 break; 2454 } 2455 current_ev = ieee80211_bss(&rdev->wiphy, info, bss, 2456 current_ev, end_buf); 2457 if (IS_ERR(current_ev)) { 2458 err = PTR_ERR(current_ev); 2459 break; 2460 } 2461 } 2462 spin_unlock_bh(&rdev->bss_lock); 2463 2464 if (err) 2465 return err; 2466 return current_ev - buf; 2467 } 2468 2469 2470 int cfg80211_wext_giwscan(struct net_device *dev, 2471 struct iw_request_info *info, 2472 struct iw_point *data, char *extra) 2473 { 2474 struct cfg80211_registered_device *rdev; 2475 int res; 2476 2477 if (!netif_running(dev)) 2478 return -ENETDOWN; 2479 2480 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex); 2481 2482 if (IS_ERR(rdev)) 2483 return PTR_ERR(rdev); 2484 2485 if (rdev->scan_req || rdev->scan_msg) 2486 return -EAGAIN; 2487 2488 res = ieee80211_scan_results(rdev, info, extra, data->length); 2489 data->length = 0; 2490 if (res >= 0) { 2491 data->length = res; 2492 res = 0; 2493 } 2494 2495 return res; 2496 } 2497 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan); 2498 #endif 2499