1 /* 2 * cfg80211 scan result handling 3 * 4 * Copyright 2008 Johannes Berg <johannes@sipsolutions.net> 5 * Copyright 2013-2014 Intel Mobile Communications GmbH 6 */ 7 #include <linux/kernel.h> 8 #include <linux/slab.h> 9 #include <linux/module.h> 10 #include <linux/netdevice.h> 11 #include <linux/wireless.h> 12 #include <linux/nl80211.h> 13 #include <linux/etherdevice.h> 14 #include <net/arp.h> 15 #include <net/cfg80211.h> 16 #include <net/cfg80211-wext.h> 17 #include <net/iw_handler.h> 18 #include "core.h" 19 #include "nl80211.h" 20 #include "wext-compat.h" 21 #include "rdev-ops.h" 22 23 /** 24 * DOC: BSS tree/list structure 25 * 26 * At the top level, the BSS list is kept in both a list in each 27 * registered device (@bss_list) as well as an RB-tree for faster 28 * lookup. In the RB-tree, entries can be looked up using their 29 * channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID 30 * for other BSSes. 31 * 32 * Due to the possibility of hidden SSIDs, there's a second level 33 * structure, the "hidden_list" and "hidden_beacon_bss" pointer. 34 * The hidden_list connects all BSSes belonging to a single AP 35 * that has a hidden SSID, and connects beacon and probe response 36 * entries. For a probe response entry for a hidden SSID, the 37 * hidden_beacon_bss pointer points to the BSS struct holding the 38 * beacon's information. 39 * 40 * Reference counting is done for all these references except for 41 * the hidden_list, so that a beacon BSS struct that is otherwise 42 * not referenced has one reference for being on the bss_list and 43 * one for each probe response entry that points to it using the 44 * hidden_beacon_bss pointer. When a BSS struct that has such a 45 * pointer is get/put, the refcount update is also propagated to 46 * the referenced struct, this ensure that it cannot get removed 47 * while somebody is using the probe response version. 48 * 49 * Note that the hidden_beacon_bss pointer never changes, due to 50 * the reference counting. Therefore, no locking is needed for 51 * it. 52 * 53 * Also note that the hidden_beacon_bss pointer is only relevant 54 * if the driver uses something other than the IEs, e.g. private 55 * data stored stored in the BSS struct, since the beacon IEs are 56 * also linked into the probe response struct. 57 */ 58 59 #define IEEE80211_SCAN_RESULT_EXPIRE (30 * HZ) 60 61 static void bss_free(struct cfg80211_internal_bss *bss) 62 { 63 struct cfg80211_bss_ies *ies; 64 65 if (WARN_ON(atomic_read(&bss->hold))) 66 return; 67 68 ies = (void *)rcu_access_pointer(bss->pub.beacon_ies); 69 if (ies && !bss->pub.hidden_beacon_bss) 70 kfree_rcu(ies, rcu_head); 71 ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies); 72 if (ies) 73 kfree_rcu(ies, rcu_head); 74 75 /* 76 * This happens when the module is removed, it doesn't 77 * really matter any more save for completeness 78 */ 79 if (!list_empty(&bss->hidden_list)) 80 list_del(&bss->hidden_list); 81 82 kfree(bss); 83 } 84 85 static inline void bss_ref_get(struct cfg80211_registered_device *rdev, 86 struct cfg80211_internal_bss *bss) 87 { 88 lockdep_assert_held(&rdev->bss_lock); 89 90 bss->refcount++; 91 if (bss->pub.hidden_beacon_bss) { 92 bss = container_of(bss->pub.hidden_beacon_bss, 93 struct cfg80211_internal_bss, 94 pub); 95 bss->refcount++; 96 } 97 } 98 99 static inline void bss_ref_put(struct cfg80211_registered_device *rdev, 100 struct cfg80211_internal_bss *bss) 101 { 102 lockdep_assert_held(&rdev->bss_lock); 103 104 if (bss->pub.hidden_beacon_bss) { 105 struct cfg80211_internal_bss *hbss; 106 hbss = container_of(bss->pub.hidden_beacon_bss, 107 struct cfg80211_internal_bss, 108 pub); 109 hbss->refcount--; 110 if (hbss->refcount == 0) 111 bss_free(hbss); 112 } 113 bss->refcount--; 114 if (bss->refcount == 0) 115 bss_free(bss); 116 } 117 118 static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev, 119 struct cfg80211_internal_bss *bss) 120 { 121 lockdep_assert_held(&rdev->bss_lock); 122 123 if (!list_empty(&bss->hidden_list)) { 124 /* 125 * don't remove the beacon entry if it has 126 * probe responses associated with it 127 */ 128 if (!bss->pub.hidden_beacon_bss) 129 return false; 130 /* 131 * if it's a probe response entry break its 132 * link to the other entries in the group 133 */ 134 list_del_init(&bss->hidden_list); 135 } 136 137 list_del_init(&bss->list); 138 rb_erase(&bss->rbn, &rdev->bss_tree); 139 bss_ref_put(rdev, bss); 140 return true; 141 } 142 143 static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev, 144 unsigned long expire_time) 145 { 146 struct cfg80211_internal_bss *bss, *tmp; 147 bool expired = false; 148 149 lockdep_assert_held(&rdev->bss_lock); 150 151 list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) { 152 if (atomic_read(&bss->hold)) 153 continue; 154 if (!time_after(expire_time, bss->ts)) 155 continue; 156 157 if (__cfg80211_unlink_bss(rdev, bss)) 158 expired = true; 159 } 160 161 if (expired) 162 rdev->bss_generation++; 163 } 164 165 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev, 166 bool send_message) 167 { 168 struct cfg80211_scan_request *request; 169 struct wireless_dev *wdev; 170 struct sk_buff *msg; 171 #ifdef CONFIG_CFG80211_WEXT 172 union iwreq_data wrqu; 173 #endif 174 175 ASSERT_RTNL(); 176 177 if (rdev->scan_msg) { 178 nl80211_send_scan_result(rdev, rdev->scan_msg); 179 rdev->scan_msg = NULL; 180 return; 181 } 182 183 request = rdev->scan_req; 184 if (!request) 185 return; 186 187 wdev = request->wdev; 188 189 /* 190 * This must be before sending the other events! 191 * Otherwise, wpa_supplicant gets completely confused with 192 * wext events. 193 */ 194 if (wdev->netdev) 195 cfg80211_sme_scan_done(wdev->netdev); 196 197 if (!request->aborted && 198 request->flags & NL80211_SCAN_FLAG_FLUSH) { 199 /* flush entries from previous scans */ 200 spin_lock_bh(&rdev->bss_lock); 201 __cfg80211_bss_expire(rdev, request->scan_start); 202 spin_unlock_bh(&rdev->bss_lock); 203 } 204 205 msg = nl80211_build_scan_msg(rdev, wdev, request->aborted); 206 207 #ifdef CONFIG_CFG80211_WEXT 208 if (wdev->netdev && !request->aborted) { 209 memset(&wrqu, 0, sizeof(wrqu)); 210 211 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL); 212 } 213 #endif 214 215 if (wdev->netdev) 216 dev_put(wdev->netdev); 217 218 rdev->scan_req = NULL; 219 kfree(request); 220 221 if (!send_message) 222 rdev->scan_msg = msg; 223 else 224 nl80211_send_scan_result(rdev, msg); 225 } 226 227 void __cfg80211_scan_done(struct work_struct *wk) 228 { 229 struct cfg80211_registered_device *rdev; 230 231 rdev = container_of(wk, struct cfg80211_registered_device, 232 scan_done_wk); 233 234 rtnl_lock(); 235 ___cfg80211_scan_done(rdev, true); 236 rtnl_unlock(); 237 } 238 239 void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted) 240 { 241 trace_cfg80211_scan_done(request, aborted); 242 WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req); 243 244 request->aborted = aborted; 245 request->notified = true; 246 queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk); 247 } 248 EXPORT_SYMBOL(cfg80211_scan_done); 249 250 void __cfg80211_sched_scan_results(struct work_struct *wk) 251 { 252 struct cfg80211_registered_device *rdev; 253 struct cfg80211_sched_scan_request *request; 254 255 rdev = container_of(wk, struct cfg80211_registered_device, 256 sched_scan_results_wk); 257 258 rtnl_lock(); 259 260 request = rtnl_dereference(rdev->sched_scan_req); 261 262 /* we don't have sched_scan_req anymore if the scan is stopping */ 263 if (request) { 264 if (request->flags & NL80211_SCAN_FLAG_FLUSH) { 265 /* flush entries from previous scans */ 266 spin_lock_bh(&rdev->bss_lock); 267 __cfg80211_bss_expire(rdev, request->scan_start); 268 spin_unlock_bh(&rdev->bss_lock); 269 request->scan_start = jiffies; 270 } 271 nl80211_send_sched_scan_results(rdev, request->dev); 272 } 273 274 rtnl_unlock(); 275 } 276 277 void cfg80211_sched_scan_results(struct wiphy *wiphy) 278 { 279 trace_cfg80211_sched_scan_results(wiphy); 280 /* ignore if we're not scanning */ 281 282 if (rcu_access_pointer(wiphy_to_rdev(wiphy)->sched_scan_req)) 283 queue_work(cfg80211_wq, 284 &wiphy_to_rdev(wiphy)->sched_scan_results_wk); 285 } 286 EXPORT_SYMBOL(cfg80211_sched_scan_results); 287 288 void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy) 289 { 290 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 291 292 ASSERT_RTNL(); 293 294 trace_cfg80211_sched_scan_stopped(wiphy); 295 296 __cfg80211_stop_sched_scan(rdev, true); 297 } 298 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_rtnl); 299 300 void cfg80211_sched_scan_stopped(struct wiphy *wiphy) 301 { 302 rtnl_lock(); 303 cfg80211_sched_scan_stopped_rtnl(wiphy); 304 rtnl_unlock(); 305 } 306 EXPORT_SYMBOL(cfg80211_sched_scan_stopped); 307 308 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev, 309 bool driver_initiated) 310 { 311 struct cfg80211_sched_scan_request *sched_scan_req; 312 struct net_device *dev; 313 314 ASSERT_RTNL(); 315 316 if (!rdev->sched_scan_req) 317 return -ENOENT; 318 319 sched_scan_req = rtnl_dereference(rdev->sched_scan_req); 320 dev = sched_scan_req->dev; 321 322 if (!driver_initiated) { 323 int err = rdev_sched_scan_stop(rdev, dev); 324 if (err) 325 return err; 326 } 327 328 nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED); 329 330 RCU_INIT_POINTER(rdev->sched_scan_req, NULL); 331 kfree_rcu(sched_scan_req, rcu_head); 332 333 return 0; 334 } 335 336 void cfg80211_bss_age(struct cfg80211_registered_device *rdev, 337 unsigned long age_secs) 338 { 339 struct cfg80211_internal_bss *bss; 340 unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC); 341 342 spin_lock_bh(&rdev->bss_lock); 343 list_for_each_entry(bss, &rdev->bss_list, list) 344 bss->ts -= age_jiffies; 345 spin_unlock_bh(&rdev->bss_lock); 346 } 347 348 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev) 349 { 350 __cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE); 351 } 352 353 const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len) 354 { 355 while (len > 2 && ies[0] != eid) { 356 len -= ies[1] + 2; 357 ies += ies[1] + 2; 358 } 359 if (len < 2) 360 return NULL; 361 if (len < 2 + ies[1]) 362 return NULL; 363 return ies; 364 } 365 EXPORT_SYMBOL(cfg80211_find_ie); 366 367 const u8 *cfg80211_find_vendor_ie(unsigned int oui, int oui_type, 368 const u8 *ies, int len) 369 { 370 struct ieee80211_vendor_ie *ie; 371 const u8 *pos = ies, *end = ies + len; 372 int ie_oui; 373 374 if (WARN_ON(oui_type > 0xff)) 375 return NULL; 376 377 while (pos < end) { 378 pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos, 379 end - pos); 380 if (!pos) 381 return NULL; 382 383 ie = (struct ieee80211_vendor_ie *)pos; 384 385 /* make sure we can access ie->len */ 386 BUILD_BUG_ON(offsetof(struct ieee80211_vendor_ie, len) != 1); 387 388 if (ie->len < sizeof(*ie)) 389 goto cont; 390 391 ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2]; 392 if (ie_oui == oui && 393 (oui_type < 0 || ie->oui_type == oui_type)) 394 return pos; 395 cont: 396 pos += 2 + ie->len; 397 } 398 return NULL; 399 } 400 EXPORT_SYMBOL(cfg80211_find_vendor_ie); 401 402 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid, 403 const u8 *ssid, size_t ssid_len) 404 { 405 const struct cfg80211_bss_ies *ies; 406 const u8 *ssidie; 407 408 if (bssid && !ether_addr_equal(a->bssid, bssid)) 409 return false; 410 411 if (!ssid) 412 return true; 413 414 ies = rcu_access_pointer(a->ies); 415 if (!ies) 416 return false; 417 ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 418 if (!ssidie) 419 return false; 420 if (ssidie[1] != ssid_len) 421 return false; 422 return memcmp(ssidie + 2, ssid, ssid_len) == 0; 423 } 424 425 /** 426 * enum bss_compare_mode - BSS compare mode 427 * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find) 428 * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode 429 * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode 430 */ 431 enum bss_compare_mode { 432 BSS_CMP_REGULAR, 433 BSS_CMP_HIDE_ZLEN, 434 BSS_CMP_HIDE_NUL, 435 }; 436 437 static int cmp_bss(struct cfg80211_bss *a, 438 struct cfg80211_bss *b, 439 enum bss_compare_mode mode) 440 { 441 const struct cfg80211_bss_ies *a_ies, *b_ies; 442 const u8 *ie1 = NULL; 443 const u8 *ie2 = NULL; 444 int i, r; 445 446 if (a->channel != b->channel) 447 return b->channel->center_freq - a->channel->center_freq; 448 449 a_ies = rcu_access_pointer(a->ies); 450 if (!a_ies) 451 return -1; 452 b_ies = rcu_access_pointer(b->ies); 453 if (!b_ies) 454 return 1; 455 456 if (WLAN_CAPABILITY_IS_STA_BSS(a->capability)) 457 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID, 458 a_ies->data, a_ies->len); 459 if (WLAN_CAPABILITY_IS_STA_BSS(b->capability)) 460 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID, 461 b_ies->data, b_ies->len); 462 if (ie1 && ie2) { 463 int mesh_id_cmp; 464 465 if (ie1[1] == ie2[1]) 466 mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]); 467 else 468 mesh_id_cmp = ie2[1] - ie1[1]; 469 470 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, 471 a_ies->data, a_ies->len); 472 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, 473 b_ies->data, b_ies->len); 474 if (ie1 && ie2) { 475 if (mesh_id_cmp) 476 return mesh_id_cmp; 477 if (ie1[1] != ie2[1]) 478 return ie2[1] - ie1[1]; 479 return memcmp(ie1 + 2, ie2 + 2, ie1[1]); 480 } 481 } 482 483 r = memcmp(a->bssid, b->bssid, sizeof(a->bssid)); 484 if (r) 485 return r; 486 487 ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len); 488 ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len); 489 490 if (!ie1 && !ie2) 491 return 0; 492 493 /* 494 * Note that with "hide_ssid", the function returns a match if 495 * the already-present BSS ("b") is a hidden SSID beacon for 496 * the new BSS ("a"). 497 */ 498 499 /* sort missing IE before (left of) present IE */ 500 if (!ie1) 501 return -1; 502 if (!ie2) 503 return 1; 504 505 switch (mode) { 506 case BSS_CMP_HIDE_ZLEN: 507 /* 508 * In ZLEN mode we assume the BSS entry we're 509 * looking for has a zero-length SSID. So if 510 * the one we're looking at right now has that, 511 * return 0. Otherwise, return the difference 512 * in length, but since we're looking for the 513 * 0-length it's really equivalent to returning 514 * the length of the one we're looking at. 515 * 516 * No content comparison is needed as we assume 517 * the content length is zero. 518 */ 519 return ie2[1]; 520 case BSS_CMP_REGULAR: 521 default: 522 /* sort by length first, then by contents */ 523 if (ie1[1] != ie2[1]) 524 return ie2[1] - ie1[1]; 525 return memcmp(ie1 + 2, ie2 + 2, ie1[1]); 526 case BSS_CMP_HIDE_NUL: 527 if (ie1[1] != ie2[1]) 528 return ie2[1] - ie1[1]; 529 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */ 530 for (i = 0; i < ie2[1]; i++) 531 if (ie2[i + 2]) 532 return -1; 533 return 0; 534 } 535 } 536 537 static bool cfg80211_bss_type_match(u16 capability, 538 enum nl80211_band band, 539 enum ieee80211_bss_type bss_type) 540 { 541 bool ret = true; 542 u16 mask, val; 543 544 if (bss_type == IEEE80211_BSS_TYPE_ANY) 545 return ret; 546 547 if (band == NL80211_BAND_60GHZ) { 548 mask = WLAN_CAPABILITY_DMG_TYPE_MASK; 549 switch (bss_type) { 550 case IEEE80211_BSS_TYPE_ESS: 551 val = WLAN_CAPABILITY_DMG_TYPE_AP; 552 break; 553 case IEEE80211_BSS_TYPE_PBSS: 554 val = WLAN_CAPABILITY_DMG_TYPE_PBSS; 555 break; 556 case IEEE80211_BSS_TYPE_IBSS: 557 val = WLAN_CAPABILITY_DMG_TYPE_IBSS; 558 break; 559 default: 560 return false; 561 } 562 } else { 563 mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS; 564 switch (bss_type) { 565 case IEEE80211_BSS_TYPE_ESS: 566 val = WLAN_CAPABILITY_ESS; 567 break; 568 case IEEE80211_BSS_TYPE_IBSS: 569 val = WLAN_CAPABILITY_IBSS; 570 break; 571 case IEEE80211_BSS_TYPE_MBSS: 572 val = 0; 573 break; 574 default: 575 return false; 576 } 577 } 578 579 ret = ((capability & mask) == val); 580 return ret; 581 } 582 583 /* Returned bss is reference counted and must be cleaned up appropriately. */ 584 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy, 585 struct ieee80211_channel *channel, 586 const u8 *bssid, 587 const u8 *ssid, size_t ssid_len, 588 enum ieee80211_bss_type bss_type, 589 enum ieee80211_privacy privacy) 590 { 591 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 592 struct cfg80211_internal_bss *bss, *res = NULL; 593 unsigned long now = jiffies; 594 int bss_privacy; 595 596 trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type, 597 privacy); 598 599 spin_lock_bh(&rdev->bss_lock); 600 601 list_for_each_entry(bss, &rdev->bss_list, list) { 602 if (!cfg80211_bss_type_match(bss->pub.capability, 603 bss->pub.channel->band, bss_type)) 604 continue; 605 606 bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY); 607 if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) || 608 (privacy == IEEE80211_PRIVACY_OFF && bss_privacy)) 609 continue; 610 if (channel && bss->pub.channel != channel) 611 continue; 612 if (!is_valid_ether_addr(bss->pub.bssid)) 613 continue; 614 /* Don't get expired BSS structs */ 615 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) && 616 !atomic_read(&bss->hold)) 617 continue; 618 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) { 619 res = bss; 620 bss_ref_get(rdev, res); 621 break; 622 } 623 } 624 625 spin_unlock_bh(&rdev->bss_lock); 626 if (!res) 627 return NULL; 628 trace_cfg80211_return_bss(&res->pub); 629 return &res->pub; 630 } 631 EXPORT_SYMBOL(cfg80211_get_bss); 632 633 static void rb_insert_bss(struct cfg80211_registered_device *rdev, 634 struct cfg80211_internal_bss *bss) 635 { 636 struct rb_node **p = &rdev->bss_tree.rb_node; 637 struct rb_node *parent = NULL; 638 struct cfg80211_internal_bss *tbss; 639 int cmp; 640 641 while (*p) { 642 parent = *p; 643 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn); 644 645 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR); 646 647 if (WARN_ON(!cmp)) { 648 /* will sort of leak this BSS */ 649 return; 650 } 651 652 if (cmp < 0) 653 p = &(*p)->rb_left; 654 else 655 p = &(*p)->rb_right; 656 } 657 658 rb_link_node(&bss->rbn, parent, p); 659 rb_insert_color(&bss->rbn, &rdev->bss_tree); 660 } 661 662 static struct cfg80211_internal_bss * 663 rb_find_bss(struct cfg80211_registered_device *rdev, 664 struct cfg80211_internal_bss *res, 665 enum bss_compare_mode mode) 666 { 667 struct rb_node *n = rdev->bss_tree.rb_node; 668 struct cfg80211_internal_bss *bss; 669 int r; 670 671 while (n) { 672 bss = rb_entry(n, struct cfg80211_internal_bss, rbn); 673 r = cmp_bss(&res->pub, &bss->pub, mode); 674 675 if (r == 0) 676 return bss; 677 else if (r < 0) 678 n = n->rb_left; 679 else 680 n = n->rb_right; 681 } 682 683 return NULL; 684 } 685 686 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev, 687 struct cfg80211_internal_bss *new) 688 { 689 const struct cfg80211_bss_ies *ies; 690 struct cfg80211_internal_bss *bss; 691 const u8 *ie; 692 int i, ssidlen; 693 u8 fold = 0; 694 695 ies = rcu_access_pointer(new->pub.beacon_ies); 696 if (WARN_ON(!ies)) 697 return false; 698 699 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 700 if (!ie) { 701 /* nothing to do */ 702 return true; 703 } 704 705 ssidlen = ie[1]; 706 for (i = 0; i < ssidlen; i++) 707 fold |= ie[2 + i]; 708 709 if (fold) { 710 /* not a hidden SSID */ 711 return true; 712 } 713 714 /* This is the bad part ... */ 715 716 list_for_each_entry(bss, &rdev->bss_list, list) { 717 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid)) 718 continue; 719 if (bss->pub.channel != new->pub.channel) 720 continue; 721 if (bss->pub.scan_width != new->pub.scan_width) 722 continue; 723 if (rcu_access_pointer(bss->pub.beacon_ies)) 724 continue; 725 ies = rcu_access_pointer(bss->pub.ies); 726 if (!ies) 727 continue; 728 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 729 if (!ie) 730 continue; 731 if (ssidlen && ie[1] != ssidlen) 732 continue; 733 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss)) 734 continue; 735 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list))) 736 list_del(&bss->hidden_list); 737 /* combine them */ 738 list_add(&bss->hidden_list, &new->hidden_list); 739 bss->pub.hidden_beacon_bss = &new->pub; 740 new->refcount += bss->refcount; 741 rcu_assign_pointer(bss->pub.beacon_ies, 742 new->pub.beacon_ies); 743 } 744 745 return true; 746 } 747 748 /* Returned bss is reference counted and must be cleaned up appropriately. */ 749 static struct cfg80211_internal_bss * 750 cfg80211_bss_update(struct cfg80211_registered_device *rdev, 751 struct cfg80211_internal_bss *tmp, 752 bool signal_valid) 753 { 754 struct cfg80211_internal_bss *found = NULL; 755 756 if (WARN_ON(!tmp->pub.channel)) 757 return NULL; 758 759 tmp->ts = jiffies; 760 761 spin_lock_bh(&rdev->bss_lock); 762 763 if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) { 764 spin_unlock_bh(&rdev->bss_lock); 765 return NULL; 766 } 767 768 found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR); 769 770 if (found) { 771 /* Update IEs */ 772 if (rcu_access_pointer(tmp->pub.proberesp_ies)) { 773 const struct cfg80211_bss_ies *old; 774 775 old = rcu_access_pointer(found->pub.proberesp_ies); 776 777 rcu_assign_pointer(found->pub.proberesp_ies, 778 tmp->pub.proberesp_ies); 779 /* Override possible earlier Beacon frame IEs */ 780 rcu_assign_pointer(found->pub.ies, 781 tmp->pub.proberesp_ies); 782 if (old) 783 kfree_rcu((struct cfg80211_bss_ies *)old, 784 rcu_head); 785 } else if (rcu_access_pointer(tmp->pub.beacon_ies)) { 786 const struct cfg80211_bss_ies *old; 787 struct cfg80211_internal_bss *bss; 788 789 if (found->pub.hidden_beacon_bss && 790 !list_empty(&found->hidden_list)) { 791 const struct cfg80211_bss_ies *f; 792 793 /* 794 * The found BSS struct is one of the probe 795 * response members of a group, but we're 796 * receiving a beacon (beacon_ies in the tmp 797 * bss is used). This can only mean that the 798 * AP changed its beacon from not having an 799 * SSID to showing it, which is confusing so 800 * drop this information. 801 */ 802 803 f = rcu_access_pointer(tmp->pub.beacon_ies); 804 kfree_rcu((struct cfg80211_bss_ies *)f, 805 rcu_head); 806 goto drop; 807 } 808 809 old = rcu_access_pointer(found->pub.beacon_ies); 810 811 rcu_assign_pointer(found->pub.beacon_ies, 812 tmp->pub.beacon_ies); 813 814 /* Override IEs if they were from a beacon before */ 815 if (old == rcu_access_pointer(found->pub.ies)) 816 rcu_assign_pointer(found->pub.ies, 817 tmp->pub.beacon_ies); 818 819 /* Assign beacon IEs to all sub entries */ 820 list_for_each_entry(bss, &found->hidden_list, 821 hidden_list) { 822 const struct cfg80211_bss_ies *ies; 823 824 ies = rcu_access_pointer(bss->pub.beacon_ies); 825 WARN_ON(ies != old); 826 827 rcu_assign_pointer(bss->pub.beacon_ies, 828 tmp->pub.beacon_ies); 829 } 830 831 if (old) 832 kfree_rcu((struct cfg80211_bss_ies *)old, 833 rcu_head); 834 } 835 836 found->pub.beacon_interval = tmp->pub.beacon_interval; 837 /* 838 * don't update the signal if beacon was heard on 839 * adjacent channel. 840 */ 841 if (signal_valid) 842 found->pub.signal = tmp->pub.signal; 843 found->pub.capability = tmp->pub.capability; 844 found->ts = tmp->ts; 845 found->ts_boottime = tmp->ts_boottime; 846 } else { 847 struct cfg80211_internal_bss *new; 848 struct cfg80211_internal_bss *hidden; 849 struct cfg80211_bss_ies *ies; 850 851 /* 852 * create a copy -- the "res" variable that is passed in 853 * is allocated on the stack since it's not needed in the 854 * more common case of an update 855 */ 856 new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size, 857 GFP_ATOMIC); 858 if (!new) { 859 ies = (void *)rcu_dereference(tmp->pub.beacon_ies); 860 if (ies) 861 kfree_rcu(ies, rcu_head); 862 ies = (void *)rcu_dereference(tmp->pub.proberesp_ies); 863 if (ies) 864 kfree_rcu(ies, rcu_head); 865 goto drop; 866 } 867 memcpy(new, tmp, sizeof(*new)); 868 new->refcount = 1; 869 INIT_LIST_HEAD(&new->hidden_list); 870 871 if (rcu_access_pointer(tmp->pub.proberesp_ies)) { 872 hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN); 873 if (!hidden) 874 hidden = rb_find_bss(rdev, tmp, 875 BSS_CMP_HIDE_NUL); 876 if (hidden) { 877 new->pub.hidden_beacon_bss = &hidden->pub; 878 list_add(&new->hidden_list, 879 &hidden->hidden_list); 880 hidden->refcount++; 881 rcu_assign_pointer(new->pub.beacon_ies, 882 hidden->pub.beacon_ies); 883 } 884 } else { 885 /* 886 * Ok so we found a beacon, and don't have an entry. If 887 * it's a beacon with hidden SSID, we might be in for an 888 * expensive search for any probe responses that should 889 * be grouped with this beacon for updates ... 890 */ 891 if (!cfg80211_combine_bsses(rdev, new)) { 892 kfree(new); 893 goto drop; 894 } 895 } 896 897 list_add_tail(&new->list, &rdev->bss_list); 898 rb_insert_bss(rdev, new); 899 found = new; 900 } 901 902 rdev->bss_generation++; 903 bss_ref_get(rdev, found); 904 spin_unlock_bh(&rdev->bss_lock); 905 906 return found; 907 drop: 908 spin_unlock_bh(&rdev->bss_lock); 909 return NULL; 910 } 911 912 static struct ieee80211_channel * 913 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen, 914 struct ieee80211_channel *channel) 915 { 916 const u8 *tmp; 917 u32 freq; 918 int channel_number = -1; 919 920 tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen); 921 if (tmp && tmp[1] == 1) { 922 channel_number = tmp[2]; 923 } else { 924 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen); 925 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) { 926 struct ieee80211_ht_operation *htop = (void *)(tmp + 2); 927 928 channel_number = htop->primary_chan; 929 } 930 } 931 932 if (channel_number < 0) 933 return channel; 934 935 freq = ieee80211_channel_to_frequency(channel_number, channel->band); 936 channel = ieee80211_get_channel(wiphy, freq); 937 if (!channel) 938 return NULL; 939 if (channel->flags & IEEE80211_CHAN_DISABLED) 940 return NULL; 941 return channel; 942 } 943 944 /* Returned bss is reference counted and must be cleaned up appropriately. */ 945 struct cfg80211_bss * 946 cfg80211_inform_bss_data(struct wiphy *wiphy, 947 struct cfg80211_inform_bss *data, 948 enum cfg80211_bss_frame_type ftype, 949 const u8 *bssid, u64 tsf, u16 capability, 950 u16 beacon_interval, const u8 *ie, size_t ielen, 951 gfp_t gfp) 952 { 953 struct cfg80211_bss_ies *ies; 954 struct ieee80211_channel *channel; 955 struct cfg80211_internal_bss tmp = {}, *res; 956 int bss_type; 957 bool signal_valid; 958 959 if (WARN_ON(!wiphy)) 960 return NULL; 961 962 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC && 963 (data->signal < 0 || data->signal > 100))) 964 return NULL; 965 966 channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan); 967 if (!channel) 968 return NULL; 969 970 memcpy(tmp.pub.bssid, bssid, ETH_ALEN); 971 tmp.pub.channel = channel; 972 tmp.pub.scan_width = data->scan_width; 973 tmp.pub.signal = data->signal; 974 tmp.pub.beacon_interval = beacon_interval; 975 tmp.pub.capability = capability; 976 tmp.ts_boottime = data->boottime_ns; 977 978 /* 979 * If we do not know here whether the IEs are from a Beacon or Probe 980 * Response frame, we need to pick one of the options and only use it 981 * with the driver that does not provide the full Beacon/Probe Response 982 * frame. Use Beacon frame pointer to avoid indicating that this should 983 * override the IEs pointer should we have received an earlier 984 * indication of Probe Response data. 985 */ 986 ies = kzalloc(sizeof(*ies) + ielen, gfp); 987 if (!ies) 988 return NULL; 989 ies->len = ielen; 990 ies->tsf = tsf; 991 ies->from_beacon = false; 992 memcpy(ies->data, ie, ielen); 993 994 switch (ftype) { 995 case CFG80211_BSS_FTYPE_BEACON: 996 ies->from_beacon = true; 997 /* fall through to assign */ 998 case CFG80211_BSS_FTYPE_UNKNOWN: 999 rcu_assign_pointer(tmp.pub.beacon_ies, ies); 1000 break; 1001 case CFG80211_BSS_FTYPE_PRESP: 1002 rcu_assign_pointer(tmp.pub.proberesp_ies, ies); 1003 break; 1004 } 1005 rcu_assign_pointer(tmp.pub.ies, ies); 1006 1007 signal_valid = abs(data->chan->center_freq - channel->center_freq) <= 1008 wiphy->max_adj_channel_rssi_comp; 1009 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid); 1010 if (!res) 1011 return NULL; 1012 1013 if (channel->band == NL80211_BAND_60GHZ) { 1014 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK; 1015 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP || 1016 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS) 1017 regulatory_hint_found_beacon(wiphy, channel, gfp); 1018 } else { 1019 if (res->pub.capability & WLAN_CAPABILITY_ESS) 1020 regulatory_hint_found_beacon(wiphy, channel, gfp); 1021 } 1022 1023 trace_cfg80211_return_bss(&res->pub); 1024 /* cfg80211_bss_update gives us a referenced result */ 1025 return &res->pub; 1026 } 1027 EXPORT_SYMBOL(cfg80211_inform_bss_data); 1028 1029 /* cfg80211_inform_bss_width_frame helper */ 1030 struct cfg80211_bss * 1031 cfg80211_inform_bss_frame_data(struct wiphy *wiphy, 1032 struct cfg80211_inform_bss *data, 1033 struct ieee80211_mgmt *mgmt, size_t len, 1034 gfp_t gfp) 1035 1036 { 1037 struct cfg80211_internal_bss tmp = {}, *res; 1038 struct cfg80211_bss_ies *ies; 1039 struct ieee80211_channel *channel; 1040 bool signal_valid; 1041 size_t ielen = len - offsetof(struct ieee80211_mgmt, 1042 u.probe_resp.variable); 1043 int bss_type; 1044 1045 BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) != 1046 offsetof(struct ieee80211_mgmt, u.beacon.variable)); 1047 1048 trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len); 1049 1050 if (WARN_ON(!mgmt)) 1051 return NULL; 1052 1053 if (WARN_ON(!wiphy)) 1054 return NULL; 1055 1056 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC && 1057 (data->signal < 0 || data->signal > 100))) 1058 return NULL; 1059 1060 if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable))) 1061 return NULL; 1062 1063 channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable, 1064 ielen, data->chan); 1065 if (!channel) 1066 return NULL; 1067 1068 ies = kzalloc(sizeof(*ies) + ielen, gfp); 1069 if (!ies) 1070 return NULL; 1071 ies->len = ielen; 1072 ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp); 1073 ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control); 1074 memcpy(ies->data, mgmt->u.probe_resp.variable, ielen); 1075 1076 if (ieee80211_is_probe_resp(mgmt->frame_control)) 1077 rcu_assign_pointer(tmp.pub.proberesp_ies, ies); 1078 else 1079 rcu_assign_pointer(tmp.pub.beacon_ies, ies); 1080 rcu_assign_pointer(tmp.pub.ies, ies); 1081 1082 memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN); 1083 tmp.pub.channel = channel; 1084 tmp.pub.scan_width = data->scan_width; 1085 tmp.pub.signal = data->signal; 1086 tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int); 1087 tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info); 1088 tmp.ts_boottime = data->boottime_ns; 1089 1090 signal_valid = abs(data->chan->center_freq - channel->center_freq) <= 1091 wiphy->max_adj_channel_rssi_comp; 1092 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid); 1093 if (!res) 1094 return NULL; 1095 1096 if (channel->band == NL80211_BAND_60GHZ) { 1097 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK; 1098 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP || 1099 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS) 1100 regulatory_hint_found_beacon(wiphy, channel, gfp); 1101 } else { 1102 if (res->pub.capability & WLAN_CAPABILITY_ESS) 1103 regulatory_hint_found_beacon(wiphy, channel, gfp); 1104 } 1105 1106 trace_cfg80211_return_bss(&res->pub); 1107 /* cfg80211_bss_update gives us a referenced result */ 1108 return &res->pub; 1109 } 1110 EXPORT_SYMBOL(cfg80211_inform_bss_frame_data); 1111 1112 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 1113 { 1114 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1115 struct cfg80211_internal_bss *bss; 1116 1117 if (!pub) 1118 return; 1119 1120 bss = container_of(pub, struct cfg80211_internal_bss, pub); 1121 1122 spin_lock_bh(&rdev->bss_lock); 1123 bss_ref_get(rdev, bss); 1124 spin_unlock_bh(&rdev->bss_lock); 1125 } 1126 EXPORT_SYMBOL(cfg80211_ref_bss); 1127 1128 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 1129 { 1130 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1131 struct cfg80211_internal_bss *bss; 1132 1133 if (!pub) 1134 return; 1135 1136 bss = container_of(pub, struct cfg80211_internal_bss, pub); 1137 1138 spin_lock_bh(&rdev->bss_lock); 1139 bss_ref_put(rdev, bss); 1140 spin_unlock_bh(&rdev->bss_lock); 1141 } 1142 EXPORT_SYMBOL(cfg80211_put_bss); 1143 1144 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 1145 { 1146 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1147 struct cfg80211_internal_bss *bss; 1148 1149 if (WARN_ON(!pub)) 1150 return; 1151 1152 bss = container_of(pub, struct cfg80211_internal_bss, pub); 1153 1154 spin_lock_bh(&rdev->bss_lock); 1155 if (!list_empty(&bss->list)) { 1156 if (__cfg80211_unlink_bss(rdev, bss)) 1157 rdev->bss_generation++; 1158 } 1159 spin_unlock_bh(&rdev->bss_lock); 1160 } 1161 EXPORT_SYMBOL(cfg80211_unlink_bss); 1162 1163 #ifdef CONFIG_CFG80211_WEXT 1164 static struct cfg80211_registered_device * 1165 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex) 1166 { 1167 struct cfg80211_registered_device *rdev; 1168 struct net_device *dev; 1169 1170 ASSERT_RTNL(); 1171 1172 dev = dev_get_by_index(net, ifindex); 1173 if (!dev) 1174 return ERR_PTR(-ENODEV); 1175 if (dev->ieee80211_ptr) 1176 rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy); 1177 else 1178 rdev = ERR_PTR(-ENODEV); 1179 dev_put(dev); 1180 return rdev; 1181 } 1182 1183 int cfg80211_wext_siwscan(struct net_device *dev, 1184 struct iw_request_info *info, 1185 union iwreq_data *wrqu, char *extra) 1186 { 1187 struct cfg80211_registered_device *rdev; 1188 struct wiphy *wiphy; 1189 struct iw_scan_req *wreq = NULL; 1190 struct cfg80211_scan_request *creq = NULL; 1191 int i, err, n_channels = 0; 1192 enum nl80211_band band; 1193 1194 if (!netif_running(dev)) 1195 return -ENETDOWN; 1196 1197 if (wrqu->data.length == sizeof(struct iw_scan_req)) 1198 wreq = (struct iw_scan_req *)extra; 1199 1200 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex); 1201 1202 if (IS_ERR(rdev)) 1203 return PTR_ERR(rdev); 1204 1205 if (rdev->scan_req || rdev->scan_msg) { 1206 err = -EBUSY; 1207 goto out; 1208 } 1209 1210 wiphy = &rdev->wiphy; 1211 1212 /* Determine number of channels, needed to allocate creq */ 1213 if (wreq && wreq->num_channels) 1214 n_channels = wreq->num_channels; 1215 else 1216 n_channels = ieee80211_get_num_supported_channels(wiphy); 1217 1218 creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) + 1219 n_channels * sizeof(void *), 1220 GFP_ATOMIC); 1221 if (!creq) { 1222 err = -ENOMEM; 1223 goto out; 1224 } 1225 1226 creq->wiphy = wiphy; 1227 creq->wdev = dev->ieee80211_ptr; 1228 /* SSIDs come after channels */ 1229 creq->ssids = (void *)&creq->channels[n_channels]; 1230 creq->n_channels = n_channels; 1231 creq->n_ssids = 1; 1232 creq->scan_start = jiffies; 1233 1234 /* translate "Scan on frequencies" request */ 1235 i = 0; 1236 for (band = 0; band < NUM_NL80211_BANDS; band++) { 1237 int j; 1238 1239 if (!wiphy->bands[band]) 1240 continue; 1241 1242 for (j = 0; j < wiphy->bands[band]->n_channels; j++) { 1243 /* ignore disabled channels */ 1244 if (wiphy->bands[band]->channels[j].flags & 1245 IEEE80211_CHAN_DISABLED) 1246 continue; 1247 1248 /* If we have a wireless request structure and the 1249 * wireless request specifies frequencies, then search 1250 * for the matching hardware channel. 1251 */ 1252 if (wreq && wreq->num_channels) { 1253 int k; 1254 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq; 1255 for (k = 0; k < wreq->num_channels; k++) { 1256 struct iw_freq *freq = 1257 &wreq->channel_list[k]; 1258 int wext_freq = 1259 cfg80211_wext_freq(freq); 1260 1261 if (wext_freq == wiphy_freq) 1262 goto wext_freq_found; 1263 } 1264 goto wext_freq_not_found; 1265 } 1266 1267 wext_freq_found: 1268 creq->channels[i] = &wiphy->bands[band]->channels[j]; 1269 i++; 1270 wext_freq_not_found: ; 1271 } 1272 } 1273 /* No channels found? */ 1274 if (!i) { 1275 err = -EINVAL; 1276 goto out; 1277 } 1278 1279 /* Set real number of channels specified in creq->channels[] */ 1280 creq->n_channels = i; 1281 1282 /* translate "Scan for SSID" request */ 1283 if (wreq) { 1284 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) { 1285 if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) { 1286 err = -EINVAL; 1287 goto out; 1288 } 1289 memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len); 1290 creq->ssids[0].ssid_len = wreq->essid_len; 1291 } 1292 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE) 1293 creq->n_ssids = 0; 1294 } 1295 1296 for (i = 0; i < NUM_NL80211_BANDS; i++) 1297 if (wiphy->bands[i]) 1298 creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1; 1299 1300 eth_broadcast_addr(creq->bssid); 1301 1302 rdev->scan_req = creq; 1303 err = rdev_scan(rdev, creq); 1304 if (err) { 1305 rdev->scan_req = NULL; 1306 /* creq will be freed below */ 1307 } else { 1308 nl80211_send_scan_start(rdev, dev->ieee80211_ptr); 1309 /* creq now owned by driver */ 1310 creq = NULL; 1311 dev_hold(dev); 1312 } 1313 out: 1314 kfree(creq); 1315 return err; 1316 } 1317 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan); 1318 1319 static char *ieee80211_scan_add_ies(struct iw_request_info *info, 1320 const struct cfg80211_bss_ies *ies, 1321 char *current_ev, char *end_buf) 1322 { 1323 const u8 *pos, *end, *next; 1324 struct iw_event iwe; 1325 1326 if (!ies) 1327 return current_ev; 1328 1329 /* 1330 * If needed, fragment the IEs buffer (at IE boundaries) into short 1331 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages. 1332 */ 1333 pos = ies->data; 1334 end = pos + ies->len; 1335 1336 while (end - pos > IW_GENERIC_IE_MAX) { 1337 next = pos + 2 + pos[1]; 1338 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX) 1339 next = next + 2 + next[1]; 1340 1341 memset(&iwe, 0, sizeof(iwe)); 1342 iwe.cmd = IWEVGENIE; 1343 iwe.u.data.length = next - pos; 1344 current_ev = iwe_stream_add_point_check(info, current_ev, 1345 end_buf, &iwe, 1346 (void *)pos); 1347 if (IS_ERR(current_ev)) 1348 return current_ev; 1349 pos = next; 1350 } 1351 1352 if (end > pos) { 1353 memset(&iwe, 0, sizeof(iwe)); 1354 iwe.cmd = IWEVGENIE; 1355 iwe.u.data.length = end - pos; 1356 current_ev = iwe_stream_add_point_check(info, current_ev, 1357 end_buf, &iwe, 1358 (void *)pos); 1359 if (IS_ERR(current_ev)) 1360 return current_ev; 1361 } 1362 1363 return current_ev; 1364 } 1365 1366 static char * 1367 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info, 1368 struct cfg80211_internal_bss *bss, char *current_ev, 1369 char *end_buf) 1370 { 1371 const struct cfg80211_bss_ies *ies; 1372 struct iw_event iwe; 1373 const u8 *ie; 1374 u8 buf[50]; 1375 u8 *cfg, *p, *tmp; 1376 int rem, i, sig; 1377 bool ismesh = false; 1378 1379 memset(&iwe, 0, sizeof(iwe)); 1380 iwe.cmd = SIOCGIWAP; 1381 iwe.u.ap_addr.sa_family = ARPHRD_ETHER; 1382 memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN); 1383 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 1384 IW_EV_ADDR_LEN); 1385 if (IS_ERR(current_ev)) 1386 return current_ev; 1387 1388 memset(&iwe, 0, sizeof(iwe)); 1389 iwe.cmd = SIOCGIWFREQ; 1390 iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq); 1391 iwe.u.freq.e = 0; 1392 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 1393 IW_EV_FREQ_LEN); 1394 if (IS_ERR(current_ev)) 1395 return current_ev; 1396 1397 memset(&iwe, 0, sizeof(iwe)); 1398 iwe.cmd = SIOCGIWFREQ; 1399 iwe.u.freq.m = bss->pub.channel->center_freq; 1400 iwe.u.freq.e = 6; 1401 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 1402 IW_EV_FREQ_LEN); 1403 if (IS_ERR(current_ev)) 1404 return current_ev; 1405 1406 if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) { 1407 memset(&iwe, 0, sizeof(iwe)); 1408 iwe.cmd = IWEVQUAL; 1409 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED | 1410 IW_QUAL_NOISE_INVALID | 1411 IW_QUAL_QUAL_UPDATED; 1412 switch (wiphy->signal_type) { 1413 case CFG80211_SIGNAL_TYPE_MBM: 1414 sig = bss->pub.signal / 100; 1415 iwe.u.qual.level = sig; 1416 iwe.u.qual.updated |= IW_QUAL_DBM; 1417 if (sig < -110) /* rather bad */ 1418 sig = -110; 1419 else if (sig > -40) /* perfect */ 1420 sig = -40; 1421 /* will give a range of 0 .. 70 */ 1422 iwe.u.qual.qual = sig + 110; 1423 break; 1424 case CFG80211_SIGNAL_TYPE_UNSPEC: 1425 iwe.u.qual.level = bss->pub.signal; 1426 /* will give range 0 .. 100 */ 1427 iwe.u.qual.qual = bss->pub.signal; 1428 break; 1429 default: 1430 /* not reached */ 1431 break; 1432 } 1433 current_ev = iwe_stream_add_event_check(info, current_ev, 1434 end_buf, &iwe, 1435 IW_EV_QUAL_LEN); 1436 if (IS_ERR(current_ev)) 1437 return current_ev; 1438 } 1439 1440 memset(&iwe, 0, sizeof(iwe)); 1441 iwe.cmd = SIOCGIWENCODE; 1442 if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY) 1443 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY; 1444 else 1445 iwe.u.data.flags = IW_ENCODE_DISABLED; 1446 iwe.u.data.length = 0; 1447 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf, 1448 &iwe, ""); 1449 if (IS_ERR(current_ev)) 1450 return current_ev; 1451 1452 rcu_read_lock(); 1453 ies = rcu_dereference(bss->pub.ies); 1454 rem = ies->len; 1455 ie = ies->data; 1456 1457 while (rem >= 2) { 1458 /* invalid data */ 1459 if (ie[1] > rem - 2) 1460 break; 1461 1462 switch (ie[0]) { 1463 case WLAN_EID_SSID: 1464 memset(&iwe, 0, sizeof(iwe)); 1465 iwe.cmd = SIOCGIWESSID; 1466 iwe.u.data.length = ie[1]; 1467 iwe.u.data.flags = 1; 1468 current_ev = iwe_stream_add_point_check(info, 1469 current_ev, 1470 end_buf, &iwe, 1471 (u8 *)ie + 2); 1472 if (IS_ERR(current_ev)) 1473 goto unlock; 1474 break; 1475 case WLAN_EID_MESH_ID: 1476 memset(&iwe, 0, sizeof(iwe)); 1477 iwe.cmd = SIOCGIWESSID; 1478 iwe.u.data.length = ie[1]; 1479 iwe.u.data.flags = 1; 1480 current_ev = iwe_stream_add_point_check(info, 1481 current_ev, 1482 end_buf, &iwe, 1483 (u8 *)ie + 2); 1484 if (IS_ERR(current_ev)) 1485 goto unlock; 1486 break; 1487 case WLAN_EID_MESH_CONFIG: 1488 ismesh = true; 1489 if (ie[1] != sizeof(struct ieee80211_meshconf_ie)) 1490 break; 1491 cfg = (u8 *)ie + 2; 1492 memset(&iwe, 0, sizeof(iwe)); 1493 iwe.cmd = IWEVCUSTOM; 1494 sprintf(buf, "Mesh Network Path Selection Protocol ID: " 1495 "0x%02X", cfg[0]); 1496 iwe.u.data.length = strlen(buf); 1497 current_ev = iwe_stream_add_point_check(info, 1498 current_ev, 1499 end_buf, 1500 &iwe, buf); 1501 if (IS_ERR(current_ev)) 1502 goto unlock; 1503 sprintf(buf, "Path Selection Metric ID: 0x%02X", 1504 cfg[1]); 1505 iwe.u.data.length = strlen(buf); 1506 current_ev = iwe_stream_add_point_check(info, 1507 current_ev, 1508 end_buf, 1509 &iwe, buf); 1510 if (IS_ERR(current_ev)) 1511 goto unlock; 1512 sprintf(buf, "Congestion Control Mode ID: 0x%02X", 1513 cfg[2]); 1514 iwe.u.data.length = strlen(buf); 1515 current_ev = iwe_stream_add_point_check(info, 1516 current_ev, 1517 end_buf, 1518 &iwe, buf); 1519 if (IS_ERR(current_ev)) 1520 goto unlock; 1521 sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]); 1522 iwe.u.data.length = strlen(buf); 1523 current_ev = iwe_stream_add_point_check(info, 1524 current_ev, 1525 end_buf, 1526 &iwe, buf); 1527 if (IS_ERR(current_ev)) 1528 goto unlock; 1529 sprintf(buf, "Authentication ID: 0x%02X", cfg[4]); 1530 iwe.u.data.length = strlen(buf); 1531 current_ev = iwe_stream_add_point_check(info, 1532 current_ev, 1533 end_buf, 1534 &iwe, buf); 1535 if (IS_ERR(current_ev)) 1536 goto unlock; 1537 sprintf(buf, "Formation Info: 0x%02X", cfg[5]); 1538 iwe.u.data.length = strlen(buf); 1539 current_ev = iwe_stream_add_point_check(info, 1540 current_ev, 1541 end_buf, 1542 &iwe, buf); 1543 if (IS_ERR(current_ev)) 1544 goto unlock; 1545 sprintf(buf, "Capabilities: 0x%02X", cfg[6]); 1546 iwe.u.data.length = strlen(buf); 1547 current_ev = iwe_stream_add_point_check(info, 1548 current_ev, 1549 end_buf, 1550 &iwe, buf); 1551 if (IS_ERR(current_ev)) 1552 goto unlock; 1553 break; 1554 case WLAN_EID_SUPP_RATES: 1555 case WLAN_EID_EXT_SUPP_RATES: 1556 /* display all supported rates in readable format */ 1557 p = current_ev + iwe_stream_lcp_len(info); 1558 1559 memset(&iwe, 0, sizeof(iwe)); 1560 iwe.cmd = SIOCGIWRATE; 1561 /* Those two flags are ignored... */ 1562 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0; 1563 1564 for (i = 0; i < ie[1]; i++) { 1565 iwe.u.bitrate.value = 1566 ((ie[i + 2] & 0x7f) * 500000); 1567 tmp = p; 1568 p = iwe_stream_add_value(info, current_ev, p, 1569 end_buf, &iwe, 1570 IW_EV_PARAM_LEN); 1571 if (p == tmp) { 1572 current_ev = ERR_PTR(-E2BIG); 1573 goto unlock; 1574 } 1575 } 1576 current_ev = p; 1577 break; 1578 } 1579 rem -= ie[1] + 2; 1580 ie += ie[1] + 2; 1581 } 1582 1583 if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) || 1584 ismesh) { 1585 memset(&iwe, 0, sizeof(iwe)); 1586 iwe.cmd = SIOCGIWMODE; 1587 if (ismesh) 1588 iwe.u.mode = IW_MODE_MESH; 1589 else if (bss->pub.capability & WLAN_CAPABILITY_ESS) 1590 iwe.u.mode = IW_MODE_MASTER; 1591 else 1592 iwe.u.mode = IW_MODE_ADHOC; 1593 current_ev = iwe_stream_add_event_check(info, current_ev, 1594 end_buf, &iwe, 1595 IW_EV_UINT_LEN); 1596 if (IS_ERR(current_ev)) 1597 goto unlock; 1598 } 1599 1600 memset(&iwe, 0, sizeof(iwe)); 1601 iwe.cmd = IWEVCUSTOM; 1602 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf)); 1603 iwe.u.data.length = strlen(buf); 1604 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf, 1605 &iwe, buf); 1606 if (IS_ERR(current_ev)) 1607 goto unlock; 1608 memset(&iwe, 0, sizeof(iwe)); 1609 iwe.cmd = IWEVCUSTOM; 1610 sprintf(buf, " Last beacon: %ums ago", 1611 elapsed_jiffies_msecs(bss->ts)); 1612 iwe.u.data.length = strlen(buf); 1613 current_ev = iwe_stream_add_point_check(info, current_ev, 1614 end_buf, &iwe, buf); 1615 if (IS_ERR(current_ev)) 1616 goto unlock; 1617 1618 current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf); 1619 1620 unlock: 1621 rcu_read_unlock(); 1622 return current_ev; 1623 } 1624 1625 1626 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev, 1627 struct iw_request_info *info, 1628 char *buf, size_t len) 1629 { 1630 char *current_ev = buf; 1631 char *end_buf = buf + len; 1632 struct cfg80211_internal_bss *bss; 1633 int err = 0; 1634 1635 spin_lock_bh(&rdev->bss_lock); 1636 cfg80211_bss_expire(rdev); 1637 1638 list_for_each_entry(bss, &rdev->bss_list, list) { 1639 if (buf + len - current_ev <= IW_EV_ADDR_LEN) { 1640 err = -E2BIG; 1641 break; 1642 } 1643 current_ev = ieee80211_bss(&rdev->wiphy, info, bss, 1644 current_ev, end_buf); 1645 if (IS_ERR(current_ev)) { 1646 err = PTR_ERR(current_ev); 1647 break; 1648 } 1649 } 1650 spin_unlock_bh(&rdev->bss_lock); 1651 1652 if (err) 1653 return err; 1654 return current_ev - buf; 1655 } 1656 1657 1658 int cfg80211_wext_giwscan(struct net_device *dev, 1659 struct iw_request_info *info, 1660 struct iw_point *data, char *extra) 1661 { 1662 struct cfg80211_registered_device *rdev; 1663 int res; 1664 1665 if (!netif_running(dev)) 1666 return -ENETDOWN; 1667 1668 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex); 1669 1670 if (IS_ERR(rdev)) 1671 return PTR_ERR(rdev); 1672 1673 if (rdev->scan_req || rdev->scan_msg) 1674 return -EAGAIN; 1675 1676 res = ieee80211_scan_results(rdev, info, extra, data->length); 1677 data->length = 0; 1678 if (res >= 0) { 1679 data->length = res; 1680 res = 0; 1681 } 1682 1683 return res; 1684 } 1685 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan); 1686 #endif 1687