1 /* 2 * cfg80211 scan result handling 3 * 4 * Copyright 2008 Johannes Berg <johannes@sipsolutions.net> 5 * Copyright 2013-2014 Intel Mobile Communications GmbH 6 * Copyright 2016 Intel Deutschland GmbH 7 */ 8 #include <linux/kernel.h> 9 #include <linux/slab.h> 10 #include <linux/module.h> 11 #include <linux/netdevice.h> 12 #include <linux/wireless.h> 13 #include <linux/nl80211.h> 14 #include <linux/etherdevice.h> 15 #include <net/arp.h> 16 #include <net/cfg80211.h> 17 #include <net/cfg80211-wext.h> 18 #include <net/iw_handler.h> 19 #include "core.h" 20 #include "nl80211.h" 21 #include "wext-compat.h" 22 #include "rdev-ops.h" 23 24 /** 25 * DOC: BSS tree/list structure 26 * 27 * At the top level, the BSS list is kept in both a list in each 28 * registered device (@bss_list) as well as an RB-tree for faster 29 * lookup. In the RB-tree, entries can be looked up using their 30 * channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID 31 * for other BSSes. 32 * 33 * Due to the possibility of hidden SSIDs, there's a second level 34 * structure, the "hidden_list" and "hidden_beacon_bss" pointer. 35 * The hidden_list connects all BSSes belonging to a single AP 36 * that has a hidden SSID, and connects beacon and probe response 37 * entries. For a probe response entry for a hidden SSID, the 38 * hidden_beacon_bss pointer points to the BSS struct holding the 39 * beacon's information. 40 * 41 * Reference counting is done for all these references except for 42 * the hidden_list, so that a beacon BSS struct that is otherwise 43 * not referenced has one reference for being on the bss_list and 44 * one for each probe response entry that points to it using the 45 * hidden_beacon_bss pointer. When a BSS struct that has such a 46 * pointer is get/put, the refcount update is also propagated to 47 * the referenced struct, this ensure that it cannot get removed 48 * while somebody is using the probe response version. 49 * 50 * Note that the hidden_beacon_bss pointer never changes, due to 51 * the reference counting. Therefore, no locking is needed for 52 * it. 53 * 54 * Also note that the hidden_beacon_bss pointer is only relevant 55 * if the driver uses something other than the IEs, e.g. private 56 * data stored stored in the BSS struct, since the beacon IEs are 57 * also linked into the probe response struct. 58 */ 59 60 /* 61 * Limit the number of BSS entries stored in mac80211. Each one is 62 * a bit over 4k at most, so this limits to roughly 4-5M of memory. 63 * If somebody wants to really attack this though, they'd likely 64 * use small beacons, and only one type of frame, limiting each of 65 * the entries to a much smaller size (in order to generate more 66 * entries in total, so overhead is bigger.) 67 */ 68 static int bss_entries_limit = 1000; 69 module_param(bss_entries_limit, int, 0644); 70 MODULE_PARM_DESC(bss_entries_limit, 71 "limit to number of scan BSS entries (per wiphy, default 1000)"); 72 73 #define IEEE80211_SCAN_RESULT_EXPIRE (30 * HZ) 74 75 static void bss_free(struct cfg80211_internal_bss *bss) 76 { 77 struct cfg80211_bss_ies *ies; 78 79 if (WARN_ON(atomic_read(&bss->hold))) 80 return; 81 82 ies = (void *)rcu_access_pointer(bss->pub.beacon_ies); 83 if (ies && !bss->pub.hidden_beacon_bss) 84 kfree_rcu(ies, rcu_head); 85 ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies); 86 if (ies) 87 kfree_rcu(ies, rcu_head); 88 89 /* 90 * This happens when the module is removed, it doesn't 91 * really matter any more save for completeness 92 */ 93 if (!list_empty(&bss->hidden_list)) 94 list_del(&bss->hidden_list); 95 96 kfree(bss); 97 } 98 99 static inline void bss_ref_get(struct cfg80211_registered_device *rdev, 100 struct cfg80211_internal_bss *bss) 101 { 102 lockdep_assert_held(&rdev->bss_lock); 103 104 bss->refcount++; 105 if (bss->pub.hidden_beacon_bss) { 106 bss = container_of(bss->pub.hidden_beacon_bss, 107 struct cfg80211_internal_bss, 108 pub); 109 bss->refcount++; 110 } 111 } 112 113 static inline void bss_ref_put(struct cfg80211_registered_device *rdev, 114 struct cfg80211_internal_bss *bss) 115 { 116 lockdep_assert_held(&rdev->bss_lock); 117 118 if (bss->pub.hidden_beacon_bss) { 119 struct cfg80211_internal_bss *hbss; 120 hbss = container_of(bss->pub.hidden_beacon_bss, 121 struct cfg80211_internal_bss, 122 pub); 123 hbss->refcount--; 124 if (hbss->refcount == 0) 125 bss_free(hbss); 126 } 127 bss->refcount--; 128 if (bss->refcount == 0) 129 bss_free(bss); 130 } 131 132 static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev, 133 struct cfg80211_internal_bss *bss) 134 { 135 lockdep_assert_held(&rdev->bss_lock); 136 137 if (!list_empty(&bss->hidden_list)) { 138 /* 139 * don't remove the beacon entry if it has 140 * probe responses associated with it 141 */ 142 if (!bss->pub.hidden_beacon_bss) 143 return false; 144 /* 145 * if it's a probe response entry break its 146 * link to the other entries in the group 147 */ 148 list_del_init(&bss->hidden_list); 149 } 150 151 list_del_init(&bss->list); 152 rb_erase(&bss->rbn, &rdev->bss_tree); 153 rdev->bss_entries--; 154 WARN_ONCE((rdev->bss_entries == 0) ^ list_empty(&rdev->bss_list), 155 "rdev bss entries[%d]/list[empty:%d] corruption\n", 156 rdev->bss_entries, list_empty(&rdev->bss_list)); 157 bss_ref_put(rdev, bss); 158 return true; 159 } 160 161 static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev, 162 unsigned long expire_time) 163 { 164 struct cfg80211_internal_bss *bss, *tmp; 165 bool expired = false; 166 167 lockdep_assert_held(&rdev->bss_lock); 168 169 list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) { 170 if (atomic_read(&bss->hold)) 171 continue; 172 if (!time_after(expire_time, bss->ts)) 173 continue; 174 175 if (__cfg80211_unlink_bss(rdev, bss)) 176 expired = true; 177 } 178 179 if (expired) 180 rdev->bss_generation++; 181 } 182 183 static bool cfg80211_bss_expire_oldest(struct cfg80211_registered_device *rdev) 184 { 185 struct cfg80211_internal_bss *bss, *oldest = NULL; 186 bool ret; 187 188 lockdep_assert_held(&rdev->bss_lock); 189 190 list_for_each_entry(bss, &rdev->bss_list, list) { 191 if (atomic_read(&bss->hold)) 192 continue; 193 194 if (!list_empty(&bss->hidden_list) && 195 !bss->pub.hidden_beacon_bss) 196 continue; 197 198 if (oldest && time_before(oldest->ts, bss->ts)) 199 continue; 200 oldest = bss; 201 } 202 203 if (WARN_ON(!oldest)) 204 return false; 205 206 /* 207 * The callers make sure to increase rdev->bss_generation if anything 208 * gets removed (and a new entry added), so there's no need to also do 209 * it here. 210 */ 211 212 ret = __cfg80211_unlink_bss(rdev, oldest); 213 WARN_ON(!ret); 214 return ret; 215 } 216 217 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev, 218 bool send_message) 219 { 220 struct cfg80211_scan_request *request; 221 struct wireless_dev *wdev; 222 struct sk_buff *msg; 223 #ifdef CONFIG_CFG80211_WEXT 224 union iwreq_data wrqu; 225 #endif 226 227 ASSERT_RTNL(); 228 229 if (rdev->scan_msg) { 230 nl80211_send_scan_msg(rdev, rdev->scan_msg); 231 rdev->scan_msg = NULL; 232 return; 233 } 234 235 request = rdev->scan_req; 236 if (!request) 237 return; 238 239 wdev = request->wdev; 240 241 /* 242 * This must be before sending the other events! 243 * Otherwise, wpa_supplicant gets completely confused with 244 * wext events. 245 */ 246 if (wdev->netdev) 247 cfg80211_sme_scan_done(wdev->netdev); 248 249 if (!request->info.aborted && 250 request->flags & NL80211_SCAN_FLAG_FLUSH) { 251 /* flush entries from previous scans */ 252 spin_lock_bh(&rdev->bss_lock); 253 __cfg80211_bss_expire(rdev, request->scan_start); 254 spin_unlock_bh(&rdev->bss_lock); 255 } 256 257 msg = nl80211_build_scan_msg(rdev, wdev, request->info.aborted); 258 259 #ifdef CONFIG_CFG80211_WEXT 260 if (wdev->netdev && !request->info.aborted) { 261 memset(&wrqu, 0, sizeof(wrqu)); 262 263 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL); 264 } 265 #endif 266 267 if (wdev->netdev) 268 dev_put(wdev->netdev); 269 270 rdev->scan_req = NULL; 271 kfree(request); 272 273 if (!send_message) 274 rdev->scan_msg = msg; 275 else 276 nl80211_send_scan_msg(rdev, msg); 277 } 278 279 void __cfg80211_scan_done(struct work_struct *wk) 280 { 281 struct cfg80211_registered_device *rdev; 282 283 rdev = container_of(wk, struct cfg80211_registered_device, 284 scan_done_wk); 285 286 rtnl_lock(); 287 ___cfg80211_scan_done(rdev, true); 288 rtnl_unlock(); 289 } 290 291 void cfg80211_scan_done(struct cfg80211_scan_request *request, 292 struct cfg80211_scan_info *info) 293 { 294 trace_cfg80211_scan_done(request, info); 295 WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req); 296 297 request->info = *info; 298 request->notified = true; 299 queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk); 300 } 301 EXPORT_SYMBOL(cfg80211_scan_done); 302 303 void cfg80211_add_sched_scan_req(struct cfg80211_registered_device *rdev, 304 struct cfg80211_sched_scan_request *req) 305 { 306 ASSERT_RTNL(); 307 308 list_add_rcu(&req->list, &rdev->sched_scan_req_list); 309 } 310 311 static void cfg80211_del_sched_scan_req(struct cfg80211_registered_device *rdev, 312 struct cfg80211_sched_scan_request *req) 313 { 314 ASSERT_RTNL(); 315 316 list_del_rcu(&req->list); 317 kfree_rcu(req, rcu_head); 318 } 319 320 static struct cfg80211_sched_scan_request * 321 cfg80211_find_sched_scan_req(struct cfg80211_registered_device *rdev, u64 reqid) 322 { 323 struct cfg80211_sched_scan_request *pos; 324 325 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 326 327 list_for_each_entry_rcu(pos, &rdev->sched_scan_req_list, list) { 328 if (pos->reqid == reqid) 329 return pos; 330 } 331 return NULL; 332 } 333 334 /* 335 * Determines if a scheduled scan request can be handled. When a legacy 336 * scheduled scan is running no other scheduled scan is allowed regardless 337 * whether the request is for legacy or multi-support scan. When a multi-support 338 * scheduled scan is running a request for legacy scan is not allowed. In this 339 * case a request for multi-support scan can be handled if resources are 340 * available, ie. struct wiphy::max_sched_scan_reqs limit is not yet reached. 341 */ 342 int cfg80211_sched_scan_req_possible(struct cfg80211_registered_device *rdev, 343 bool want_multi) 344 { 345 struct cfg80211_sched_scan_request *pos; 346 int i = 0; 347 348 list_for_each_entry(pos, &rdev->sched_scan_req_list, list) { 349 /* request id zero means legacy in progress */ 350 if (!i && !pos->reqid) 351 return -EINPROGRESS; 352 i++; 353 } 354 355 if (i) { 356 /* no legacy allowed when multi request(s) are active */ 357 if (!want_multi) 358 return -EINPROGRESS; 359 360 /* resource limit reached */ 361 if (i == rdev->wiphy.max_sched_scan_reqs) 362 return -ENOSPC; 363 } 364 return 0; 365 } 366 367 void cfg80211_sched_scan_results_wk(struct work_struct *work) 368 { 369 struct cfg80211_registered_device *rdev; 370 struct cfg80211_sched_scan_request *req, *tmp; 371 372 rdev = container_of(work, struct cfg80211_registered_device, 373 sched_scan_res_wk); 374 375 rtnl_lock(); 376 list_for_each_entry_safe(req, tmp, &rdev->sched_scan_req_list, list) { 377 if (req->report_results) { 378 req->report_results = false; 379 if (req->flags & NL80211_SCAN_FLAG_FLUSH) { 380 /* flush entries from previous scans */ 381 spin_lock_bh(&rdev->bss_lock); 382 __cfg80211_bss_expire(rdev, req->scan_start); 383 spin_unlock_bh(&rdev->bss_lock); 384 req->scan_start = jiffies; 385 } 386 nl80211_send_sched_scan(req, 387 NL80211_CMD_SCHED_SCAN_RESULTS); 388 } 389 } 390 rtnl_unlock(); 391 } 392 393 void cfg80211_sched_scan_results(struct wiphy *wiphy, u64 reqid) 394 { 395 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 396 struct cfg80211_sched_scan_request *request; 397 398 trace_cfg80211_sched_scan_results(wiphy, reqid); 399 /* ignore if we're not scanning */ 400 401 rcu_read_lock(); 402 request = cfg80211_find_sched_scan_req(rdev, reqid); 403 if (request) { 404 request->report_results = true; 405 queue_work(cfg80211_wq, &rdev->sched_scan_res_wk); 406 } 407 rcu_read_unlock(); 408 } 409 EXPORT_SYMBOL(cfg80211_sched_scan_results); 410 411 void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy, u64 reqid) 412 { 413 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 414 415 ASSERT_RTNL(); 416 417 trace_cfg80211_sched_scan_stopped(wiphy, reqid); 418 419 __cfg80211_stop_sched_scan(rdev, reqid, true); 420 } 421 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_rtnl); 422 423 void cfg80211_sched_scan_stopped(struct wiphy *wiphy, u64 reqid) 424 { 425 rtnl_lock(); 426 cfg80211_sched_scan_stopped_rtnl(wiphy, reqid); 427 rtnl_unlock(); 428 } 429 EXPORT_SYMBOL(cfg80211_sched_scan_stopped); 430 431 int cfg80211_stop_sched_scan_req(struct cfg80211_registered_device *rdev, 432 struct cfg80211_sched_scan_request *req, 433 bool driver_initiated) 434 { 435 ASSERT_RTNL(); 436 437 if (!driver_initiated) { 438 int err = rdev_sched_scan_stop(rdev, req->dev, req->reqid); 439 if (err) 440 return err; 441 } 442 443 nl80211_send_sched_scan(req, NL80211_CMD_SCHED_SCAN_STOPPED); 444 445 cfg80211_del_sched_scan_req(rdev, req); 446 447 return 0; 448 } 449 450 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev, 451 u64 reqid, bool driver_initiated) 452 { 453 struct cfg80211_sched_scan_request *sched_scan_req; 454 455 ASSERT_RTNL(); 456 457 sched_scan_req = cfg80211_find_sched_scan_req(rdev, reqid); 458 if (!sched_scan_req) 459 return -ENOENT; 460 461 return cfg80211_stop_sched_scan_req(rdev, sched_scan_req, 462 driver_initiated); 463 } 464 465 void cfg80211_bss_age(struct cfg80211_registered_device *rdev, 466 unsigned long age_secs) 467 { 468 struct cfg80211_internal_bss *bss; 469 unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC); 470 471 spin_lock_bh(&rdev->bss_lock); 472 list_for_each_entry(bss, &rdev->bss_list, list) 473 bss->ts -= age_jiffies; 474 spin_unlock_bh(&rdev->bss_lock); 475 } 476 477 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev) 478 { 479 __cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE); 480 } 481 482 const u8 *cfg80211_find_ie_match(u8 eid, const u8 *ies, int len, 483 const u8 *match, int match_len, 484 int match_offset) 485 { 486 /* match_offset can't be smaller than 2, unless match_len is 487 * zero, in which case match_offset must be zero as well. 488 */ 489 if (WARN_ON((match_len && match_offset < 2) || 490 (!match_len && match_offset))) 491 return NULL; 492 493 while (len >= 2 && len >= ies[1] + 2) { 494 if ((ies[0] == eid) && 495 (ies[1] + 2 >= match_offset + match_len) && 496 !memcmp(ies + match_offset, match, match_len)) 497 return ies; 498 499 len -= ies[1] + 2; 500 ies += ies[1] + 2; 501 } 502 503 return NULL; 504 } 505 EXPORT_SYMBOL(cfg80211_find_ie_match); 506 507 const u8 *cfg80211_find_vendor_ie(unsigned int oui, int oui_type, 508 const u8 *ies, int len) 509 { 510 const u8 *ie; 511 u8 match[] = { oui >> 16, oui >> 8, oui, oui_type }; 512 int match_len = (oui_type < 0) ? 3 : sizeof(match); 513 514 if (WARN_ON(oui_type > 0xff)) 515 return NULL; 516 517 ie = cfg80211_find_ie_match(WLAN_EID_VENDOR_SPECIFIC, ies, len, 518 match, match_len, 2); 519 520 if (ie && (ie[1] < 4)) 521 return NULL; 522 523 return ie; 524 } 525 EXPORT_SYMBOL(cfg80211_find_vendor_ie); 526 527 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid, 528 const u8 *ssid, size_t ssid_len) 529 { 530 const struct cfg80211_bss_ies *ies; 531 const u8 *ssidie; 532 533 if (bssid && !ether_addr_equal(a->bssid, bssid)) 534 return false; 535 536 if (!ssid) 537 return true; 538 539 ies = rcu_access_pointer(a->ies); 540 if (!ies) 541 return false; 542 ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 543 if (!ssidie) 544 return false; 545 if (ssidie[1] != ssid_len) 546 return false; 547 return memcmp(ssidie + 2, ssid, ssid_len) == 0; 548 } 549 550 /** 551 * enum bss_compare_mode - BSS compare mode 552 * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find) 553 * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode 554 * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode 555 */ 556 enum bss_compare_mode { 557 BSS_CMP_REGULAR, 558 BSS_CMP_HIDE_ZLEN, 559 BSS_CMP_HIDE_NUL, 560 }; 561 562 static int cmp_bss(struct cfg80211_bss *a, 563 struct cfg80211_bss *b, 564 enum bss_compare_mode mode) 565 { 566 const struct cfg80211_bss_ies *a_ies, *b_ies; 567 const u8 *ie1 = NULL; 568 const u8 *ie2 = NULL; 569 int i, r; 570 571 if (a->channel != b->channel) 572 return b->channel->center_freq - a->channel->center_freq; 573 574 a_ies = rcu_access_pointer(a->ies); 575 if (!a_ies) 576 return -1; 577 b_ies = rcu_access_pointer(b->ies); 578 if (!b_ies) 579 return 1; 580 581 if (WLAN_CAPABILITY_IS_STA_BSS(a->capability)) 582 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID, 583 a_ies->data, a_ies->len); 584 if (WLAN_CAPABILITY_IS_STA_BSS(b->capability)) 585 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID, 586 b_ies->data, b_ies->len); 587 if (ie1 && ie2) { 588 int mesh_id_cmp; 589 590 if (ie1[1] == ie2[1]) 591 mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]); 592 else 593 mesh_id_cmp = ie2[1] - ie1[1]; 594 595 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, 596 a_ies->data, a_ies->len); 597 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, 598 b_ies->data, b_ies->len); 599 if (ie1 && ie2) { 600 if (mesh_id_cmp) 601 return mesh_id_cmp; 602 if (ie1[1] != ie2[1]) 603 return ie2[1] - ie1[1]; 604 return memcmp(ie1 + 2, ie2 + 2, ie1[1]); 605 } 606 } 607 608 r = memcmp(a->bssid, b->bssid, sizeof(a->bssid)); 609 if (r) 610 return r; 611 612 ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len); 613 ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len); 614 615 if (!ie1 && !ie2) 616 return 0; 617 618 /* 619 * Note that with "hide_ssid", the function returns a match if 620 * the already-present BSS ("b") is a hidden SSID beacon for 621 * the new BSS ("a"). 622 */ 623 624 /* sort missing IE before (left of) present IE */ 625 if (!ie1) 626 return -1; 627 if (!ie2) 628 return 1; 629 630 switch (mode) { 631 case BSS_CMP_HIDE_ZLEN: 632 /* 633 * In ZLEN mode we assume the BSS entry we're 634 * looking for has a zero-length SSID. So if 635 * the one we're looking at right now has that, 636 * return 0. Otherwise, return the difference 637 * in length, but since we're looking for the 638 * 0-length it's really equivalent to returning 639 * the length of the one we're looking at. 640 * 641 * No content comparison is needed as we assume 642 * the content length is zero. 643 */ 644 return ie2[1]; 645 case BSS_CMP_REGULAR: 646 default: 647 /* sort by length first, then by contents */ 648 if (ie1[1] != ie2[1]) 649 return ie2[1] - ie1[1]; 650 return memcmp(ie1 + 2, ie2 + 2, ie1[1]); 651 case BSS_CMP_HIDE_NUL: 652 if (ie1[1] != ie2[1]) 653 return ie2[1] - ie1[1]; 654 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */ 655 for (i = 0; i < ie2[1]; i++) 656 if (ie2[i + 2]) 657 return -1; 658 return 0; 659 } 660 } 661 662 static bool cfg80211_bss_type_match(u16 capability, 663 enum nl80211_band band, 664 enum ieee80211_bss_type bss_type) 665 { 666 bool ret = true; 667 u16 mask, val; 668 669 if (bss_type == IEEE80211_BSS_TYPE_ANY) 670 return ret; 671 672 if (band == NL80211_BAND_60GHZ) { 673 mask = WLAN_CAPABILITY_DMG_TYPE_MASK; 674 switch (bss_type) { 675 case IEEE80211_BSS_TYPE_ESS: 676 val = WLAN_CAPABILITY_DMG_TYPE_AP; 677 break; 678 case IEEE80211_BSS_TYPE_PBSS: 679 val = WLAN_CAPABILITY_DMG_TYPE_PBSS; 680 break; 681 case IEEE80211_BSS_TYPE_IBSS: 682 val = WLAN_CAPABILITY_DMG_TYPE_IBSS; 683 break; 684 default: 685 return false; 686 } 687 } else { 688 mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS; 689 switch (bss_type) { 690 case IEEE80211_BSS_TYPE_ESS: 691 val = WLAN_CAPABILITY_ESS; 692 break; 693 case IEEE80211_BSS_TYPE_IBSS: 694 val = WLAN_CAPABILITY_IBSS; 695 break; 696 case IEEE80211_BSS_TYPE_MBSS: 697 val = 0; 698 break; 699 default: 700 return false; 701 } 702 } 703 704 ret = ((capability & mask) == val); 705 return ret; 706 } 707 708 /* Returned bss is reference counted and must be cleaned up appropriately. */ 709 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy, 710 struct ieee80211_channel *channel, 711 const u8 *bssid, 712 const u8 *ssid, size_t ssid_len, 713 enum ieee80211_bss_type bss_type, 714 enum ieee80211_privacy privacy) 715 { 716 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 717 struct cfg80211_internal_bss *bss, *res = NULL; 718 unsigned long now = jiffies; 719 int bss_privacy; 720 721 trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type, 722 privacy); 723 724 spin_lock_bh(&rdev->bss_lock); 725 726 list_for_each_entry(bss, &rdev->bss_list, list) { 727 if (!cfg80211_bss_type_match(bss->pub.capability, 728 bss->pub.channel->band, bss_type)) 729 continue; 730 731 bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY); 732 if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) || 733 (privacy == IEEE80211_PRIVACY_OFF && bss_privacy)) 734 continue; 735 if (channel && bss->pub.channel != channel) 736 continue; 737 if (!is_valid_ether_addr(bss->pub.bssid)) 738 continue; 739 /* Don't get expired BSS structs */ 740 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) && 741 !atomic_read(&bss->hold)) 742 continue; 743 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) { 744 res = bss; 745 bss_ref_get(rdev, res); 746 break; 747 } 748 } 749 750 spin_unlock_bh(&rdev->bss_lock); 751 if (!res) 752 return NULL; 753 trace_cfg80211_return_bss(&res->pub); 754 return &res->pub; 755 } 756 EXPORT_SYMBOL(cfg80211_get_bss); 757 758 static void rb_insert_bss(struct cfg80211_registered_device *rdev, 759 struct cfg80211_internal_bss *bss) 760 { 761 struct rb_node **p = &rdev->bss_tree.rb_node; 762 struct rb_node *parent = NULL; 763 struct cfg80211_internal_bss *tbss; 764 int cmp; 765 766 while (*p) { 767 parent = *p; 768 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn); 769 770 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR); 771 772 if (WARN_ON(!cmp)) { 773 /* will sort of leak this BSS */ 774 return; 775 } 776 777 if (cmp < 0) 778 p = &(*p)->rb_left; 779 else 780 p = &(*p)->rb_right; 781 } 782 783 rb_link_node(&bss->rbn, parent, p); 784 rb_insert_color(&bss->rbn, &rdev->bss_tree); 785 } 786 787 static struct cfg80211_internal_bss * 788 rb_find_bss(struct cfg80211_registered_device *rdev, 789 struct cfg80211_internal_bss *res, 790 enum bss_compare_mode mode) 791 { 792 struct rb_node *n = rdev->bss_tree.rb_node; 793 struct cfg80211_internal_bss *bss; 794 int r; 795 796 while (n) { 797 bss = rb_entry(n, struct cfg80211_internal_bss, rbn); 798 r = cmp_bss(&res->pub, &bss->pub, mode); 799 800 if (r == 0) 801 return bss; 802 else if (r < 0) 803 n = n->rb_left; 804 else 805 n = n->rb_right; 806 } 807 808 return NULL; 809 } 810 811 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev, 812 struct cfg80211_internal_bss *new) 813 { 814 const struct cfg80211_bss_ies *ies; 815 struct cfg80211_internal_bss *bss; 816 const u8 *ie; 817 int i, ssidlen; 818 u8 fold = 0; 819 u32 n_entries = 0; 820 821 ies = rcu_access_pointer(new->pub.beacon_ies); 822 if (WARN_ON(!ies)) 823 return false; 824 825 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 826 if (!ie) { 827 /* nothing to do */ 828 return true; 829 } 830 831 ssidlen = ie[1]; 832 for (i = 0; i < ssidlen; i++) 833 fold |= ie[2 + i]; 834 835 if (fold) { 836 /* not a hidden SSID */ 837 return true; 838 } 839 840 /* This is the bad part ... */ 841 842 list_for_each_entry(bss, &rdev->bss_list, list) { 843 /* 844 * we're iterating all the entries anyway, so take the 845 * opportunity to validate the list length accounting 846 */ 847 n_entries++; 848 849 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid)) 850 continue; 851 if (bss->pub.channel != new->pub.channel) 852 continue; 853 if (bss->pub.scan_width != new->pub.scan_width) 854 continue; 855 if (rcu_access_pointer(bss->pub.beacon_ies)) 856 continue; 857 ies = rcu_access_pointer(bss->pub.ies); 858 if (!ies) 859 continue; 860 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 861 if (!ie) 862 continue; 863 if (ssidlen && ie[1] != ssidlen) 864 continue; 865 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss)) 866 continue; 867 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list))) 868 list_del(&bss->hidden_list); 869 /* combine them */ 870 list_add(&bss->hidden_list, &new->hidden_list); 871 bss->pub.hidden_beacon_bss = &new->pub; 872 new->refcount += bss->refcount; 873 rcu_assign_pointer(bss->pub.beacon_ies, 874 new->pub.beacon_ies); 875 } 876 877 WARN_ONCE(n_entries != rdev->bss_entries, 878 "rdev bss entries[%d]/list[len:%d] corruption\n", 879 rdev->bss_entries, n_entries); 880 881 return true; 882 } 883 884 /* Returned bss is reference counted and must be cleaned up appropriately. */ 885 static struct cfg80211_internal_bss * 886 cfg80211_bss_update(struct cfg80211_registered_device *rdev, 887 struct cfg80211_internal_bss *tmp, 888 bool signal_valid) 889 { 890 struct cfg80211_internal_bss *found = NULL; 891 892 if (WARN_ON(!tmp->pub.channel)) 893 return NULL; 894 895 tmp->ts = jiffies; 896 897 spin_lock_bh(&rdev->bss_lock); 898 899 if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) { 900 spin_unlock_bh(&rdev->bss_lock); 901 return NULL; 902 } 903 904 found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR); 905 906 if (found) { 907 /* Update IEs */ 908 if (rcu_access_pointer(tmp->pub.proberesp_ies)) { 909 const struct cfg80211_bss_ies *old; 910 911 old = rcu_access_pointer(found->pub.proberesp_ies); 912 913 rcu_assign_pointer(found->pub.proberesp_ies, 914 tmp->pub.proberesp_ies); 915 /* Override possible earlier Beacon frame IEs */ 916 rcu_assign_pointer(found->pub.ies, 917 tmp->pub.proberesp_ies); 918 if (old) 919 kfree_rcu((struct cfg80211_bss_ies *)old, 920 rcu_head); 921 } else if (rcu_access_pointer(tmp->pub.beacon_ies)) { 922 const struct cfg80211_bss_ies *old; 923 struct cfg80211_internal_bss *bss; 924 925 if (found->pub.hidden_beacon_bss && 926 !list_empty(&found->hidden_list)) { 927 const struct cfg80211_bss_ies *f; 928 929 /* 930 * The found BSS struct is one of the probe 931 * response members of a group, but we're 932 * receiving a beacon (beacon_ies in the tmp 933 * bss is used). This can only mean that the 934 * AP changed its beacon from not having an 935 * SSID to showing it, which is confusing so 936 * drop this information. 937 */ 938 939 f = rcu_access_pointer(tmp->pub.beacon_ies); 940 kfree_rcu((struct cfg80211_bss_ies *)f, 941 rcu_head); 942 goto drop; 943 } 944 945 old = rcu_access_pointer(found->pub.beacon_ies); 946 947 rcu_assign_pointer(found->pub.beacon_ies, 948 tmp->pub.beacon_ies); 949 950 /* Override IEs if they were from a beacon before */ 951 if (old == rcu_access_pointer(found->pub.ies)) 952 rcu_assign_pointer(found->pub.ies, 953 tmp->pub.beacon_ies); 954 955 /* Assign beacon IEs to all sub entries */ 956 list_for_each_entry(bss, &found->hidden_list, 957 hidden_list) { 958 const struct cfg80211_bss_ies *ies; 959 960 ies = rcu_access_pointer(bss->pub.beacon_ies); 961 WARN_ON(ies != old); 962 963 rcu_assign_pointer(bss->pub.beacon_ies, 964 tmp->pub.beacon_ies); 965 } 966 967 if (old) 968 kfree_rcu((struct cfg80211_bss_ies *)old, 969 rcu_head); 970 } 971 972 found->pub.beacon_interval = tmp->pub.beacon_interval; 973 /* 974 * don't update the signal if beacon was heard on 975 * adjacent channel. 976 */ 977 if (signal_valid) 978 found->pub.signal = tmp->pub.signal; 979 found->pub.capability = tmp->pub.capability; 980 found->ts = tmp->ts; 981 found->ts_boottime = tmp->ts_boottime; 982 found->parent_tsf = tmp->parent_tsf; 983 ether_addr_copy(found->parent_bssid, tmp->parent_bssid); 984 } else { 985 struct cfg80211_internal_bss *new; 986 struct cfg80211_internal_bss *hidden; 987 struct cfg80211_bss_ies *ies; 988 989 /* 990 * create a copy -- the "res" variable that is passed in 991 * is allocated on the stack since it's not needed in the 992 * more common case of an update 993 */ 994 new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size, 995 GFP_ATOMIC); 996 if (!new) { 997 ies = (void *)rcu_dereference(tmp->pub.beacon_ies); 998 if (ies) 999 kfree_rcu(ies, rcu_head); 1000 ies = (void *)rcu_dereference(tmp->pub.proberesp_ies); 1001 if (ies) 1002 kfree_rcu(ies, rcu_head); 1003 goto drop; 1004 } 1005 memcpy(new, tmp, sizeof(*new)); 1006 new->refcount = 1; 1007 INIT_LIST_HEAD(&new->hidden_list); 1008 1009 if (rcu_access_pointer(tmp->pub.proberesp_ies)) { 1010 hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN); 1011 if (!hidden) 1012 hidden = rb_find_bss(rdev, tmp, 1013 BSS_CMP_HIDE_NUL); 1014 if (hidden) { 1015 new->pub.hidden_beacon_bss = &hidden->pub; 1016 list_add(&new->hidden_list, 1017 &hidden->hidden_list); 1018 hidden->refcount++; 1019 rcu_assign_pointer(new->pub.beacon_ies, 1020 hidden->pub.beacon_ies); 1021 } 1022 } else { 1023 /* 1024 * Ok so we found a beacon, and don't have an entry. If 1025 * it's a beacon with hidden SSID, we might be in for an 1026 * expensive search for any probe responses that should 1027 * be grouped with this beacon for updates ... 1028 */ 1029 if (!cfg80211_combine_bsses(rdev, new)) { 1030 kfree(new); 1031 goto drop; 1032 } 1033 } 1034 1035 if (rdev->bss_entries >= bss_entries_limit && 1036 !cfg80211_bss_expire_oldest(rdev)) { 1037 kfree(new); 1038 goto drop; 1039 } 1040 1041 list_add_tail(&new->list, &rdev->bss_list); 1042 rdev->bss_entries++; 1043 rb_insert_bss(rdev, new); 1044 found = new; 1045 } 1046 1047 rdev->bss_generation++; 1048 bss_ref_get(rdev, found); 1049 spin_unlock_bh(&rdev->bss_lock); 1050 1051 return found; 1052 drop: 1053 spin_unlock_bh(&rdev->bss_lock); 1054 return NULL; 1055 } 1056 1057 static struct ieee80211_channel * 1058 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen, 1059 struct ieee80211_channel *channel) 1060 { 1061 const u8 *tmp; 1062 u32 freq; 1063 int channel_number = -1; 1064 1065 tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen); 1066 if (tmp && tmp[1] == 1) { 1067 channel_number = tmp[2]; 1068 } else { 1069 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen); 1070 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) { 1071 struct ieee80211_ht_operation *htop = (void *)(tmp + 2); 1072 1073 channel_number = htop->primary_chan; 1074 } 1075 } 1076 1077 if (channel_number < 0) 1078 return channel; 1079 1080 freq = ieee80211_channel_to_frequency(channel_number, channel->band); 1081 channel = ieee80211_get_channel(wiphy, freq); 1082 if (!channel) 1083 return NULL; 1084 if (channel->flags & IEEE80211_CHAN_DISABLED) 1085 return NULL; 1086 return channel; 1087 } 1088 1089 /* Returned bss is reference counted and must be cleaned up appropriately. */ 1090 struct cfg80211_bss * 1091 cfg80211_inform_bss_data(struct wiphy *wiphy, 1092 struct cfg80211_inform_bss *data, 1093 enum cfg80211_bss_frame_type ftype, 1094 const u8 *bssid, u64 tsf, u16 capability, 1095 u16 beacon_interval, const u8 *ie, size_t ielen, 1096 gfp_t gfp) 1097 { 1098 struct cfg80211_bss_ies *ies; 1099 struct ieee80211_channel *channel; 1100 struct cfg80211_internal_bss tmp = {}, *res; 1101 int bss_type; 1102 bool signal_valid; 1103 1104 if (WARN_ON(!wiphy)) 1105 return NULL; 1106 1107 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC && 1108 (data->signal < 0 || data->signal > 100))) 1109 return NULL; 1110 1111 channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan); 1112 if (!channel) 1113 return NULL; 1114 1115 memcpy(tmp.pub.bssid, bssid, ETH_ALEN); 1116 tmp.pub.channel = channel; 1117 tmp.pub.scan_width = data->scan_width; 1118 tmp.pub.signal = data->signal; 1119 tmp.pub.beacon_interval = beacon_interval; 1120 tmp.pub.capability = capability; 1121 tmp.ts_boottime = data->boottime_ns; 1122 1123 /* 1124 * If we do not know here whether the IEs are from a Beacon or Probe 1125 * Response frame, we need to pick one of the options and only use it 1126 * with the driver that does not provide the full Beacon/Probe Response 1127 * frame. Use Beacon frame pointer to avoid indicating that this should 1128 * override the IEs pointer should we have received an earlier 1129 * indication of Probe Response data. 1130 */ 1131 ies = kzalloc(sizeof(*ies) + ielen, gfp); 1132 if (!ies) 1133 return NULL; 1134 ies->len = ielen; 1135 ies->tsf = tsf; 1136 ies->from_beacon = false; 1137 memcpy(ies->data, ie, ielen); 1138 1139 switch (ftype) { 1140 case CFG80211_BSS_FTYPE_BEACON: 1141 ies->from_beacon = true; 1142 /* fall through to assign */ 1143 case CFG80211_BSS_FTYPE_UNKNOWN: 1144 rcu_assign_pointer(tmp.pub.beacon_ies, ies); 1145 break; 1146 case CFG80211_BSS_FTYPE_PRESP: 1147 rcu_assign_pointer(tmp.pub.proberesp_ies, ies); 1148 break; 1149 } 1150 rcu_assign_pointer(tmp.pub.ies, ies); 1151 1152 signal_valid = abs(data->chan->center_freq - channel->center_freq) <= 1153 wiphy->max_adj_channel_rssi_comp; 1154 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid); 1155 if (!res) 1156 return NULL; 1157 1158 if (channel->band == NL80211_BAND_60GHZ) { 1159 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK; 1160 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP || 1161 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS) 1162 regulatory_hint_found_beacon(wiphy, channel, gfp); 1163 } else { 1164 if (res->pub.capability & WLAN_CAPABILITY_ESS) 1165 regulatory_hint_found_beacon(wiphy, channel, gfp); 1166 } 1167 1168 trace_cfg80211_return_bss(&res->pub); 1169 /* cfg80211_bss_update gives us a referenced result */ 1170 return &res->pub; 1171 } 1172 EXPORT_SYMBOL(cfg80211_inform_bss_data); 1173 1174 /* cfg80211_inform_bss_width_frame helper */ 1175 struct cfg80211_bss * 1176 cfg80211_inform_bss_frame_data(struct wiphy *wiphy, 1177 struct cfg80211_inform_bss *data, 1178 struct ieee80211_mgmt *mgmt, size_t len, 1179 gfp_t gfp) 1180 1181 { 1182 struct cfg80211_internal_bss tmp = {}, *res; 1183 struct cfg80211_bss_ies *ies; 1184 struct ieee80211_channel *channel; 1185 bool signal_valid; 1186 size_t ielen = len - offsetof(struct ieee80211_mgmt, 1187 u.probe_resp.variable); 1188 int bss_type; 1189 1190 BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) != 1191 offsetof(struct ieee80211_mgmt, u.beacon.variable)); 1192 1193 trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len); 1194 1195 if (WARN_ON(!mgmt)) 1196 return NULL; 1197 1198 if (WARN_ON(!wiphy)) 1199 return NULL; 1200 1201 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC && 1202 (data->signal < 0 || data->signal > 100))) 1203 return NULL; 1204 1205 if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable))) 1206 return NULL; 1207 1208 channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable, 1209 ielen, data->chan); 1210 if (!channel) 1211 return NULL; 1212 1213 ies = kzalloc(sizeof(*ies) + ielen, gfp); 1214 if (!ies) 1215 return NULL; 1216 ies->len = ielen; 1217 ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp); 1218 ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control); 1219 memcpy(ies->data, mgmt->u.probe_resp.variable, ielen); 1220 1221 if (ieee80211_is_probe_resp(mgmt->frame_control)) 1222 rcu_assign_pointer(tmp.pub.proberesp_ies, ies); 1223 else 1224 rcu_assign_pointer(tmp.pub.beacon_ies, ies); 1225 rcu_assign_pointer(tmp.pub.ies, ies); 1226 1227 memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN); 1228 tmp.pub.channel = channel; 1229 tmp.pub.scan_width = data->scan_width; 1230 tmp.pub.signal = data->signal; 1231 tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int); 1232 tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info); 1233 tmp.ts_boottime = data->boottime_ns; 1234 tmp.parent_tsf = data->parent_tsf; 1235 ether_addr_copy(tmp.parent_bssid, data->parent_bssid); 1236 1237 signal_valid = abs(data->chan->center_freq - channel->center_freq) <= 1238 wiphy->max_adj_channel_rssi_comp; 1239 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid); 1240 if (!res) 1241 return NULL; 1242 1243 if (channel->band == NL80211_BAND_60GHZ) { 1244 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK; 1245 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP || 1246 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS) 1247 regulatory_hint_found_beacon(wiphy, channel, gfp); 1248 } else { 1249 if (res->pub.capability & WLAN_CAPABILITY_ESS) 1250 regulatory_hint_found_beacon(wiphy, channel, gfp); 1251 } 1252 1253 trace_cfg80211_return_bss(&res->pub); 1254 /* cfg80211_bss_update gives us a referenced result */ 1255 return &res->pub; 1256 } 1257 EXPORT_SYMBOL(cfg80211_inform_bss_frame_data); 1258 1259 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 1260 { 1261 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1262 struct cfg80211_internal_bss *bss; 1263 1264 if (!pub) 1265 return; 1266 1267 bss = container_of(pub, struct cfg80211_internal_bss, pub); 1268 1269 spin_lock_bh(&rdev->bss_lock); 1270 bss_ref_get(rdev, bss); 1271 spin_unlock_bh(&rdev->bss_lock); 1272 } 1273 EXPORT_SYMBOL(cfg80211_ref_bss); 1274 1275 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 1276 { 1277 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1278 struct cfg80211_internal_bss *bss; 1279 1280 if (!pub) 1281 return; 1282 1283 bss = container_of(pub, struct cfg80211_internal_bss, pub); 1284 1285 spin_lock_bh(&rdev->bss_lock); 1286 bss_ref_put(rdev, bss); 1287 spin_unlock_bh(&rdev->bss_lock); 1288 } 1289 EXPORT_SYMBOL(cfg80211_put_bss); 1290 1291 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 1292 { 1293 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1294 struct cfg80211_internal_bss *bss; 1295 1296 if (WARN_ON(!pub)) 1297 return; 1298 1299 bss = container_of(pub, struct cfg80211_internal_bss, pub); 1300 1301 spin_lock_bh(&rdev->bss_lock); 1302 if (!list_empty(&bss->list)) { 1303 if (__cfg80211_unlink_bss(rdev, bss)) 1304 rdev->bss_generation++; 1305 } 1306 spin_unlock_bh(&rdev->bss_lock); 1307 } 1308 EXPORT_SYMBOL(cfg80211_unlink_bss); 1309 1310 #ifdef CONFIG_CFG80211_WEXT 1311 static struct cfg80211_registered_device * 1312 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex) 1313 { 1314 struct cfg80211_registered_device *rdev; 1315 struct net_device *dev; 1316 1317 ASSERT_RTNL(); 1318 1319 dev = dev_get_by_index(net, ifindex); 1320 if (!dev) 1321 return ERR_PTR(-ENODEV); 1322 if (dev->ieee80211_ptr) 1323 rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy); 1324 else 1325 rdev = ERR_PTR(-ENODEV); 1326 dev_put(dev); 1327 return rdev; 1328 } 1329 1330 int cfg80211_wext_siwscan(struct net_device *dev, 1331 struct iw_request_info *info, 1332 union iwreq_data *wrqu, char *extra) 1333 { 1334 struct cfg80211_registered_device *rdev; 1335 struct wiphy *wiphy; 1336 struct iw_scan_req *wreq = NULL; 1337 struct cfg80211_scan_request *creq = NULL; 1338 int i, err, n_channels = 0; 1339 enum nl80211_band band; 1340 1341 if (!netif_running(dev)) 1342 return -ENETDOWN; 1343 1344 if (wrqu->data.length == sizeof(struct iw_scan_req)) 1345 wreq = (struct iw_scan_req *)extra; 1346 1347 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex); 1348 1349 if (IS_ERR(rdev)) 1350 return PTR_ERR(rdev); 1351 1352 if (rdev->scan_req || rdev->scan_msg) { 1353 err = -EBUSY; 1354 goto out; 1355 } 1356 1357 wiphy = &rdev->wiphy; 1358 1359 /* Determine number of channels, needed to allocate creq */ 1360 if (wreq && wreq->num_channels) 1361 n_channels = wreq->num_channels; 1362 else 1363 n_channels = ieee80211_get_num_supported_channels(wiphy); 1364 1365 creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) + 1366 n_channels * sizeof(void *), 1367 GFP_ATOMIC); 1368 if (!creq) { 1369 err = -ENOMEM; 1370 goto out; 1371 } 1372 1373 creq->wiphy = wiphy; 1374 creq->wdev = dev->ieee80211_ptr; 1375 /* SSIDs come after channels */ 1376 creq->ssids = (void *)&creq->channels[n_channels]; 1377 creq->n_channels = n_channels; 1378 creq->n_ssids = 1; 1379 creq->scan_start = jiffies; 1380 1381 /* translate "Scan on frequencies" request */ 1382 i = 0; 1383 for (band = 0; band < NUM_NL80211_BANDS; band++) { 1384 int j; 1385 1386 if (!wiphy->bands[band]) 1387 continue; 1388 1389 for (j = 0; j < wiphy->bands[band]->n_channels; j++) { 1390 /* ignore disabled channels */ 1391 if (wiphy->bands[band]->channels[j].flags & 1392 IEEE80211_CHAN_DISABLED) 1393 continue; 1394 1395 /* If we have a wireless request structure and the 1396 * wireless request specifies frequencies, then search 1397 * for the matching hardware channel. 1398 */ 1399 if (wreq && wreq->num_channels) { 1400 int k; 1401 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq; 1402 for (k = 0; k < wreq->num_channels; k++) { 1403 struct iw_freq *freq = 1404 &wreq->channel_list[k]; 1405 int wext_freq = 1406 cfg80211_wext_freq(freq); 1407 1408 if (wext_freq == wiphy_freq) 1409 goto wext_freq_found; 1410 } 1411 goto wext_freq_not_found; 1412 } 1413 1414 wext_freq_found: 1415 creq->channels[i] = &wiphy->bands[band]->channels[j]; 1416 i++; 1417 wext_freq_not_found: ; 1418 } 1419 } 1420 /* No channels found? */ 1421 if (!i) { 1422 err = -EINVAL; 1423 goto out; 1424 } 1425 1426 /* Set real number of channels specified in creq->channels[] */ 1427 creq->n_channels = i; 1428 1429 /* translate "Scan for SSID" request */ 1430 if (wreq) { 1431 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) { 1432 if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) { 1433 err = -EINVAL; 1434 goto out; 1435 } 1436 memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len); 1437 creq->ssids[0].ssid_len = wreq->essid_len; 1438 } 1439 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE) 1440 creq->n_ssids = 0; 1441 } 1442 1443 for (i = 0; i < NUM_NL80211_BANDS; i++) 1444 if (wiphy->bands[i]) 1445 creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1; 1446 1447 eth_broadcast_addr(creq->bssid); 1448 1449 rdev->scan_req = creq; 1450 err = rdev_scan(rdev, creq); 1451 if (err) { 1452 rdev->scan_req = NULL; 1453 /* creq will be freed below */ 1454 } else { 1455 nl80211_send_scan_start(rdev, dev->ieee80211_ptr); 1456 /* creq now owned by driver */ 1457 creq = NULL; 1458 dev_hold(dev); 1459 } 1460 out: 1461 kfree(creq); 1462 return err; 1463 } 1464 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan); 1465 1466 static char *ieee80211_scan_add_ies(struct iw_request_info *info, 1467 const struct cfg80211_bss_ies *ies, 1468 char *current_ev, char *end_buf) 1469 { 1470 const u8 *pos, *end, *next; 1471 struct iw_event iwe; 1472 1473 if (!ies) 1474 return current_ev; 1475 1476 /* 1477 * If needed, fragment the IEs buffer (at IE boundaries) into short 1478 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages. 1479 */ 1480 pos = ies->data; 1481 end = pos + ies->len; 1482 1483 while (end - pos > IW_GENERIC_IE_MAX) { 1484 next = pos + 2 + pos[1]; 1485 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX) 1486 next = next + 2 + next[1]; 1487 1488 memset(&iwe, 0, sizeof(iwe)); 1489 iwe.cmd = IWEVGENIE; 1490 iwe.u.data.length = next - pos; 1491 current_ev = iwe_stream_add_point_check(info, current_ev, 1492 end_buf, &iwe, 1493 (void *)pos); 1494 if (IS_ERR(current_ev)) 1495 return current_ev; 1496 pos = next; 1497 } 1498 1499 if (end > pos) { 1500 memset(&iwe, 0, sizeof(iwe)); 1501 iwe.cmd = IWEVGENIE; 1502 iwe.u.data.length = end - pos; 1503 current_ev = iwe_stream_add_point_check(info, current_ev, 1504 end_buf, &iwe, 1505 (void *)pos); 1506 if (IS_ERR(current_ev)) 1507 return current_ev; 1508 } 1509 1510 return current_ev; 1511 } 1512 1513 static char * 1514 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info, 1515 struct cfg80211_internal_bss *bss, char *current_ev, 1516 char *end_buf) 1517 { 1518 const struct cfg80211_bss_ies *ies; 1519 struct iw_event iwe; 1520 const u8 *ie; 1521 u8 buf[50]; 1522 u8 *cfg, *p, *tmp; 1523 int rem, i, sig; 1524 bool ismesh = false; 1525 1526 memset(&iwe, 0, sizeof(iwe)); 1527 iwe.cmd = SIOCGIWAP; 1528 iwe.u.ap_addr.sa_family = ARPHRD_ETHER; 1529 memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN); 1530 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 1531 IW_EV_ADDR_LEN); 1532 if (IS_ERR(current_ev)) 1533 return current_ev; 1534 1535 memset(&iwe, 0, sizeof(iwe)); 1536 iwe.cmd = SIOCGIWFREQ; 1537 iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq); 1538 iwe.u.freq.e = 0; 1539 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 1540 IW_EV_FREQ_LEN); 1541 if (IS_ERR(current_ev)) 1542 return current_ev; 1543 1544 memset(&iwe, 0, sizeof(iwe)); 1545 iwe.cmd = SIOCGIWFREQ; 1546 iwe.u.freq.m = bss->pub.channel->center_freq; 1547 iwe.u.freq.e = 6; 1548 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 1549 IW_EV_FREQ_LEN); 1550 if (IS_ERR(current_ev)) 1551 return current_ev; 1552 1553 if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) { 1554 memset(&iwe, 0, sizeof(iwe)); 1555 iwe.cmd = IWEVQUAL; 1556 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED | 1557 IW_QUAL_NOISE_INVALID | 1558 IW_QUAL_QUAL_UPDATED; 1559 switch (wiphy->signal_type) { 1560 case CFG80211_SIGNAL_TYPE_MBM: 1561 sig = bss->pub.signal / 100; 1562 iwe.u.qual.level = sig; 1563 iwe.u.qual.updated |= IW_QUAL_DBM; 1564 if (sig < -110) /* rather bad */ 1565 sig = -110; 1566 else if (sig > -40) /* perfect */ 1567 sig = -40; 1568 /* will give a range of 0 .. 70 */ 1569 iwe.u.qual.qual = sig + 110; 1570 break; 1571 case CFG80211_SIGNAL_TYPE_UNSPEC: 1572 iwe.u.qual.level = bss->pub.signal; 1573 /* will give range 0 .. 100 */ 1574 iwe.u.qual.qual = bss->pub.signal; 1575 break; 1576 default: 1577 /* not reached */ 1578 break; 1579 } 1580 current_ev = iwe_stream_add_event_check(info, current_ev, 1581 end_buf, &iwe, 1582 IW_EV_QUAL_LEN); 1583 if (IS_ERR(current_ev)) 1584 return current_ev; 1585 } 1586 1587 memset(&iwe, 0, sizeof(iwe)); 1588 iwe.cmd = SIOCGIWENCODE; 1589 if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY) 1590 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY; 1591 else 1592 iwe.u.data.flags = IW_ENCODE_DISABLED; 1593 iwe.u.data.length = 0; 1594 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf, 1595 &iwe, ""); 1596 if (IS_ERR(current_ev)) 1597 return current_ev; 1598 1599 rcu_read_lock(); 1600 ies = rcu_dereference(bss->pub.ies); 1601 rem = ies->len; 1602 ie = ies->data; 1603 1604 while (rem >= 2) { 1605 /* invalid data */ 1606 if (ie[1] > rem - 2) 1607 break; 1608 1609 switch (ie[0]) { 1610 case WLAN_EID_SSID: 1611 memset(&iwe, 0, sizeof(iwe)); 1612 iwe.cmd = SIOCGIWESSID; 1613 iwe.u.data.length = ie[1]; 1614 iwe.u.data.flags = 1; 1615 current_ev = iwe_stream_add_point_check(info, 1616 current_ev, 1617 end_buf, &iwe, 1618 (u8 *)ie + 2); 1619 if (IS_ERR(current_ev)) 1620 goto unlock; 1621 break; 1622 case WLAN_EID_MESH_ID: 1623 memset(&iwe, 0, sizeof(iwe)); 1624 iwe.cmd = SIOCGIWESSID; 1625 iwe.u.data.length = ie[1]; 1626 iwe.u.data.flags = 1; 1627 current_ev = iwe_stream_add_point_check(info, 1628 current_ev, 1629 end_buf, &iwe, 1630 (u8 *)ie + 2); 1631 if (IS_ERR(current_ev)) 1632 goto unlock; 1633 break; 1634 case WLAN_EID_MESH_CONFIG: 1635 ismesh = true; 1636 if (ie[1] != sizeof(struct ieee80211_meshconf_ie)) 1637 break; 1638 cfg = (u8 *)ie + 2; 1639 memset(&iwe, 0, sizeof(iwe)); 1640 iwe.cmd = IWEVCUSTOM; 1641 sprintf(buf, "Mesh Network Path Selection Protocol ID: " 1642 "0x%02X", cfg[0]); 1643 iwe.u.data.length = strlen(buf); 1644 current_ev = iwe_stream_add_point_check(info, 1645 current_ev, 1646 end_buf, 1647 &iwe, buf); 1648 if (IS_ERR(current_ev)) 1649 goto unlock; 1650 sprintf(buf, "Path Selection Metric ID: 0x%02X", 1651 cfg[1]); 1652 iwe.u.data.length = strlen(buf); 1653 current_ev = iwe_stream_add_point_check(info, 1654 current_ev, 1655 end_buf, 1656 &iwe, buf); 1657 if (IS_ERR(current_ev)) 1658 goto unlock; 1659 sprintf(buf, "Congestion Control Mode ID: 0x%02X", 1660 cfg[2]); 1661 iwe.u.data.length = strlen(buf); 1662 current_ev = iwe_stream_add_point_check(info, 1663 current_ev, 1664 end_buf, 1665 &iwe, buf); 1666 if (IS_ERR(current_ev)) 1667 goto unlock; 1668 sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]); 1669 iwe.u.data.length = strlen(buf); 1670 current_ev = iwe_stream_add_point_check(info, 1671 current_ev, 1672 end_buf, 1673 &iwe, buf); 1674 if (IS_ERR(current_ev)) 1675 goto unlock; 1676 sprintf(buf, "Authentication ID: 0x%02X", cfg[4]); 1677 iwe.u.data.length = strlen(buf); 1678 current_ev = iwe_stream_add_point_check(info, 1679 current_ev, 1680 end_buf, 1681 &iwe, buf); 1682 if (IS_ERR(current_ev)) 1683 goto unlock; 1684 sprintf(buf, "Formation Info: 0x%02X", cfg[5]); 1685 iwe.u.data.length = strlen(buf); 1686 current_ev = iwe_stream_add_point_check(info, 1687 current_ev, 1688 end_buf, 1689 &iwe, buf); 1690 if (IS_ERR(current_ev)) 1691 goto unlock; 1692 sprintf(buf, "Capabilities: 0x%02X", cfg[6]); 1693 iwe.u.data.length = strlen(buf); 1694 current_ev = iwe_stream_add_point_check(info, 1695 current_ev, 1696 end_buf, 1697 &iwe, buf); 1698 if (IS_ERR(current_ev)) 1699 goto unlock; 1700 break; 1701 case WLAN_EID_SUPP_RATES: 1702 case WLAN_EID_EXT_SUPP_RATES: 1703 /* display all supported rates in readable format */ 1704 p = current_ev + iwe_stream_lcp_len(info); 1705 1706 memset(&iwe, 0, sizeof(iwe)); 1707 iwe.cmd = SIOCGIWRATE; 1708 /* Those two flags are ignored... */ 1709 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0; 1710 1711 for (i = 0; i < ie[1]; i++) { 1712 iwe.u.bitrate.value = 1713 ((ie[i + 2] & 0x7f) * 500000); 1714 tmp = p; 1715 p = iwe_stream_add_value(info, current_ev, p, 1716 end_buf, &iwe, 1717 IW_EV_PARAM_LEN); 1718 if (p == tmp) { 1719 current_ev = ERR_PTR(-E2BIG); 1720 goto unlock; 1721 } 1722 } 1723 current_ev = p; 1724 break; 1725 } 1726 rem -= ie[1] + 2; 1727 ie += ie[1] + 2; 1728 } 1729 1730 if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) || 1731 ismesh) { 1732 memset(&iwe, 0, sizeof(iwe)); 1733 iwe.cmd = SIOCGIWMODE; 1734 if (ismesh) 1735 iwe.u.mode = IW_MODE_MESH; 1736 else if (bss->pub.capability & WLAN_CAPABILITY_ESS) 1737 iwe.u.mode = IW_MODE_MASTER; 1738 else 1739 iwe.u.mode = IW_MODE_ADHOC; 1740 current_ev = iwe_stream_add_event_check(info, current_ev, 1741 end_buf, &iwe, 1742 IW_EV_UINT_LEN); 1743 if (IS_ERR(current_ev)) 1744 goto unlock; 1745 } 1746 1747 memset(&iwe, 0, sizeof(iwe)); 1748 iwe.cmd = IWEVCUSTOM; 1749 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf)); 1750 iwe.u.data.length = strlen(buf); 1751 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf, 1752 &iwe, buf); 1753 if (IS_ERR(current_ev)) 1754 goto unlock; 1755 memset(&iwe, 0, sizeof(iwe)); 1756 iwe.cmd = IWEVCUSTOM; 1757 sprintf(buf, " Last beacon: %ums ago", 1758 elapsed_jiffies_msecs(bss->ts)); 1759 iwe.u.data.length = strlen(buf); 1760 current_ev = iwe_stream_add_point_check(info, current_ev, 1761 end_buf, &iwe, buf); 1762 if (IS_ERR(current_ev)) 1763 goto unlock; 1764 1765 current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf); 1766 1767 unlock: 1768 rcu_read_unlock(); 1769 return current_ev; 1770 } 1771 1772 1773 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev, 1774 struct iw_request_info *info, 1775 char *buf, size_t len) 1776 { 1777 char *current_ev = buf; 1778 char *end_buf = buf + len; 1779 struct cfg80211_internal_bss *bss; 1780 int err = 0; 1781 1782 spin_lock_bh(&rdev->bss_lock); 1783 cfg80211_bss_expire(rdev); 1784 1785 list_for_each_entry(bss, &rdev->bss_list, list) { 1786 if (buf + len - current_ev <= IW_EV_ADDR_LEN) { 1787 err = -E2BIG; 1788 break; 1789 } 1790 current_ev = ieee80211_bss(&rdev->wiphy, info, bss, 1791 current_ev, end_buf); 1792 if (IS_ERR(current_ev)) { 1793 err = PTR_ERR(current_ev); 1794 break; 1795 } 1796 } 1797 spin_unlock_bh(&rdev->bss_lock); 1798 1799 if (err) 1800 return err; 1801 return current_ev - buf; 1802 } 1803 1804 1805 int cfg80211_wext_giwscan(struct net_device *dev, 1806 struct iw_request_info *info, 1807 struct iw_point *data, char *extra) 1808 { 1809 struct cfg80211_registered_device *rdev; 1810 int res; 1811 1812 if (!netif_running(dev)) 1813 return -ENETDOWN; 1814 1815 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex); 1816 1817 if (IS_ERR(rdev)) 1818 return PTR_ERR(rdev); 1819 1820 if (rdev->scan_req || rdev->scan_msg) 1821 return -EAGAIN; 1822 1823 res = ieee80211_scan_results(rdev, info, extra, data->length); 1824 data->length = 0; 1825 if (res >= 0) { 1826 data->length = res; 1827 res = 0; 1828 } 1829 1830 return res; 1831 } 1832 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan); 1833 #endif 1834