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 #define IEEE80211_SCAN_RESULT_EXPIRE (30 * HZ) 61 62 static void bss_free(struct cfg80211_internal_bss *bss) 63 { 64 struct cfg80211_bss_ies *ies; 65 66 if (WARN_ON(atomic_read(&bss->hold))) 67 return; 68 69 ies = (void *)rcu_access_pointer(bss->pub.beacon_ies); 70 if (ies && !bss->pub.hidden_beacon_bss) 71 kfree_rcu(ies, rcu_head); 72 ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies); 73 if (ies) 74 kfree_rcu(ies, rcu_head); 75 76 /* 77 * This happens when the module is removed, it doesn't 78 * really matter any more save for completeness 79 */ 80 if (!list_empty(&bss->hidden_list)) 81 list_del(&bss->hidden_list); 82 83 kfree(bss); 84 } 85 86 static inline void bss_ref_get(struct cfg80211_registered_device *rdev, 87 struct cfg80211_internal_bss *bss) 88 { 89 lockdep_assert_held(&rdev->bss_lock); 90 91 bss->refcount++; 92 if (bss->pub.hidden_beacon_bss) { 93 bss = container_of(bss->pub.hidden_beacon_bss, 94 struct cfg80211_internal_bss, 95 pub); 96 bss->refcount++; 97 } 98 } 99 100 static inline void bss_ref_put(struct cfg80211_registered_device *rdev, 101 struct cfg80211_internal_bss *bss) 102 { 103 lockdep_assert_held(&rdev->bss_lock); 104 105 if (bss->pub.hidden_beacon_bss) { 106 struct cfg80211_internal_bss *hbss; 107 hbss = container_of(bss->pub.hidden_beacon_bss, 108 struct cfg80211_internal_bss, 109 pub); 110 hbss->refcount--; 111 if (hbss->refcount == 0) 112 bss_free(hbss); 113 } 114 bss->refcount--; 115 if (bss->refcount == 0) 116 bss_free(bss); 117 } 118 119 static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev, 120 struct cfg80211_internal_bss *bss) 121 { 122 lockdep_assert_held(&rdev->bss_lock); 123 124 if (!list_empty(&bss->hidden_list)) { 125 /* 126 * don't remove the beacon entry if it has 127 * probe responses associated with it 128 */ 129 if (!bss->pub.hidden_beacon_bss) 130 return false; 131 /* 132 * if it's a probe response entry break its 133 * link to the other entries in the group 134 */ 135 list_del_init(&bss->hidden_list); 136 } 137 138 list_del_init(&bss->list); 139 rb_erase(&bss->rbn, &rdev->bss_tree); 140 bss_ref_put(rdev, bss); 141 return true; 142 } 143 144 static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev, 145 unsigned long expire_time) 146 { 147 struct cfg80211_internal_bss *bss, *tmp; 148 bool expired = false; 149 150 lockdep_assert_held(&rdev->bss_lock); 151 152 list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) { 153 if (atomic_read(&bss->hold)) 154 continue; 155 if (!time_after(expire_time, bss->ts)) 156 continue; 157 158 if (__cfg80211_unlink_bss(rdev, bss)) 159 expired = true; 160 } 161 162 if (expired) 163 rdev->bss_generation++; 164 } 165 166 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev, 167 bool send_message) 168 { 169 struct cfg80211_scan_request *request; 170 struct wireless_dev *wdev; 171 struct sk_buff *msg; 172 #ifdef CONFIG_CFG80211_WEXT 173 union iwreq_data wrqu; 174 #endif 175 176 ASSERT_RTNL(); 177 178 if (rdev->scan_msg) { 179 nl80211_send_scan_result(rdev, rdev->scan_msg); 180 rdev->scan_msg = NULL; 181 return; 182 } 183 184 request = rdev->scan_req; 185 if (!request) 186 return; 187 188 wdev = request->wdev; 189 190 /* 191 * This must be before sending the other events! 192 * Otherwise, wpa_supplicant gets completely confused with 193 * wext events. 194 */ 195 if (wdev->netdev) 196 cfg80211_sme_scan_done(wdev->netdev); 197 198 if (!request->info.aborted && 199 request->flags & NL80211_SCAN_FLAG_FLUSH) { 200 /* flush entries from previous scans */ 201 spin_lock_bh(&rdev->bss_lock); 202 __cfg80211_bss_expire(rdev, request->scan_start); 203 spin_unlock_bh(&rdev->bss_lock); 204 } 205 206 msg = nl80211_build_scan_msg(rdev, wdev, request->info.aborted); 207 208 #ifdef CONFIG_CFG80211_WEXT 209 if (wdev->netdev && !request->info.aborted) { 210 memset(&wrqu, 0, sizeof(wrqu)); 211 212 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL); 213 } 214 #endif 215 216 if (wdev->netdev) 217 dev_put(wdev->netdev); 218 219 rdev->scan_req = NULL; 220 kfree(request); 221 222 if (!send_message) 223 rdev->scan_msg = msg; 224 else 225 nl80211_send_scan_result(rdev, msg); 226 } 227 228 void __cfg80211_scan_done(struct work_struct *wk) 229 { 230 struct cfg80211_registered_device *rdev; 231 232 rdev = container_of(wk, struct cfg80211_registered_device, 233 scan_done_wk); 234 235 rtnl_lock(); 236 ___cfg80211_scan_done(rdev, true); 237 rtnl_unlock(); 238 } 239 240 void cfg80211_scan_done(struct cfg80211_scan_request *request, 241 struct cfg80211_scan_info *info) 242 { 243 trace_cfg80211_scan_done(request, info); 244 WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req); 245 246 request->info = *info; 247 request->notified = true; 248 queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk); 249 } 250 EXPORT_SYMBOL(cfg80211_scan_done); 251 252 void __cfg80211_sched_scan_results(struct work_struct *wk) 253 { 254 struct cfg80211_registered_device *rdev; 255 struct cfg80211_sched_scan_request *request; 256 257 rdev = container_of(wk, struct cfg80211_registered_device, 258 sched_scan_results_wk); 259 260 rtnl_lock(); 261 262 request = rtnl_dereference(rdev->sched_scan_req); 263 264 /* we don't have sched_scan_req anymore if the scan is stopping */ 265 if (request) { 266 if (request->flags & NL80211_SCAN_FLAG_FLUSH) { 267 /* flush entries from previous scans */ 268 spin_lock_bh(&rdev->bss_lock); 269 __cfg80211_bss_expire(rdev, request->scan_start); 270 spin_unlock_bh(&rdev->bss_lock); 271 request->scan_start = jiffies; 272 } 273 nl80211_send_sched_scan_results(rdev, request->dev); 274 } 275 276 rtnl_unlock(); 277 } 278 279 void cfg80211_sched_scan_results(struct wiphy *wiphy) 280 { 281 trace_cfg80211_sched_scan_results(wiphy); 282 /* ignore if we're not scanning */ 283 284 if (rcu_access_pointer(wiphy_to_rdev(wiphy)->sched_scan_req)) 285 queue_work(cfg80211_wq, 286 &wiphy_to_rdev(wiphy)->sched_scan_results_wk); 287 } 288 EXPORT_SYMBOL(cfg80211_sched_scan_results); 289 290 void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy) 291 { 292 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 293 294 ASSERT_RTNL(); 295 296 trace_cfg80211_sched_scan_stopped(wiphy); 297 298 __cfg80211_stop_sched_scan(rdev, true); 299 } 300 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_rtnl); 301 302 void cfg80211_sched_scan_stopped(struct wiphy *wiphy) 303 { 304 rtnl_lock(); 305 cfg80211_sched_scan_stopped_rtnl(wiphy); 306 rtnl_unlock(); 307 } 308 EXPORT_SYMBOL(cfg80211_sched_scan_stopped); 309 310 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev, 311 bool driver_initiated) 312 { 313 struct cfg80211_sched_scan_request *sched_scan_req; 314 struct net_device *dev; 315 316 ASSERT_RTNL(); 317 318 if (!rdev->sched_scan_req) 319 return -ENOENT; 320 321 sched_scan_req = rtnl_dereference(rdev->sched_scan_req); 322 dev = sched_scan_req->dev; 323 324 if (!driver_initiated) { 325 int err = rdev_sched_scan_stop(rdev, dev); 326 if (err) 327 return err; 328 } 329 330 nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED); 331 332 RCU_INIT_POINTER(rdev->sched_scan_req, NULL); 333 kfree_rcu(sched_scan_req, rcu_head); 334 335 return 0; 336 } 337 338 void cfg80211_bss_age(struct cfg80211_registered_device *rdev, 339 unsigned long age_secs) 340 { 341 struct cfg80211_internal_bss *bss; 342 unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC); 343 344 spin_lock_bh(&rdev->bss_lock); 345 list_for_each_entry(bss, &rdev->bss_list, list) 346 bss->ts -= age_jiffies; 347 spin_unlock_bh(&rdev->bss_lock); 348 } 349 350 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev) 351 { 352 __cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE); 353 } 354 355 const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len) 356 { 357 while (len > 2 && ies[0] != eid) { 358 len -= ies[1] + 2; 359 ies += ies[1] + 2; 360 } 361 if (len < 2) 362 return NULL; 363 if (len < 2 + ies[1]) 364 return NULL; 365 return ies; 366 } 367 EXPORT_SYMBOL(cfg80211_find_ie); 368 369 const u8 *cfg80211_find_vendor_ie(unsigned int oui, int oui_type, 370 const u8 *ies, int len) 371 { 372 struct ieee80211_vendor_ie *ie; 373 const u8 *pos = ies, *end = ies + len; 374 int ie_oui; 375 376 if (WARN_ON(oui_type > 0xff)) 377 return NULL; 378 379 while (pos < end) { 380 pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos, 381 end - pos); 382 if (!pos) 383 return NULL; 384 385 ie = (struct ieee80211_vendor_ie *)pos; 386 387 /* make sure we can access ie->len */ 388 BUILD_BUG_ON(offsetof(struct ieee80211_vendor_ie, len) != 1); 389 390 if (ie->len < sizeof(*ie)) 391 goto cont; 392 393 ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2]; 394 if (ie_oui == oui && 395 (oui_type < 0 || ie->oui_type == oui_type)) 396 return pos; 397 cont: 398 pos += 2 + ie->len; 399 } 400 return NULL; 401 } 402 EXPORT_SYMBOL(cfg80211_find_vendor_ie); 403 404 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid, 405 const u8 *ssid, size_t ssid_len) 406 { 407 const struct cfg80211_bss_ies *ies; 408 const u8 *ssidie; 409 410 if (bssid && !ether_addr_equal(a->bssid, bssid)) 411 return false; 412 413 if (!ssid) 414 return true; 415 416 ies = rcu_access_pointer(a->ies); 417 if (!ies) 418 return false; 419 ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 420 if (!ssidie) 421 return false; 422 if (ssidie[1] != ssid_len) 423 return false; 424 return memcmp(ssidie + 2, ssid, ssid_len) == 0; 425 } 426 427 /** 428 * enum bss_compare_mode - BSS compare mode 429 * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find) 430 * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode 431 * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode 432 */ 433 enum bss_compare_mode { 434 BSS_CMP_REGULAR, 435 BSS_CMP_HIDE_ZLEN, 436 BSS_CMP_HIDE_NUL, 437 }; 438 439 static int cmp_bss(struct cfg80211_bss *a, 440 struct cfg80211_bss *b, 441 enum bss_compare_mode mode) 442 { 443 const struct cfg80211_bss_ies *a_ies, *b_ies; 444 const u8 *ie1 = NULL; 445 const u8 *ie2 = NULL; 446 int i, r; 447 448 if (a->channel != b->channel) 449 return b->channel->center_freq - a->channel->center_freq; 450 451 a_ies = rcu_access_pointer(a->ies); 452 if (!a_ies) 453 return -1; 454 b_ies = rcu_access_pointer(b->ies); 455 if (!b_ies) 456 return 1; 457 458 if (WLAN_CAPABILITY_IS_STA_BSS(a->capability)) 459 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID, 460 a_ies->data, a_ies->len); 461 if (WLAN_CAPABILITY_IS_STA_BSS(b->capability)) 462 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID, 463 b_ies->data, b_ies->len); 464 if (ie1 && ie2) { 465 int mesh_id_cmp; 466 467 if (ie1[1] == ie2[1]) 468 mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]); 469 else 470 mesh_id_cmp = ie2[1] - ie1[1]; 471 472 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, 473 a_ies->data, a_ies->len); 474 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, 475 b_ies->data, b_ies->len); 476 if (ie1 && ie2) { 477 if (mesh_id_cmp) 478 return mesh_id_cmp; 479 if (ie1[1] != ie2[1]) 480 return ie2[1] - ie1[1]; 481 return memcmp(ie1 + 2, ie2 + 2, ie1[1]); 482 } 483 } 484 485 r = memcmp(a->bssid, b->bssid, sizeof(a->bssid)); 486 if (r) 487 return r; 488 489 ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len); 490 ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len); 491 492 if (!ie1 && !ie2) 493 return 0; 494 495 /* 496 * Note that with "hide_ssid", the function returns a match if 497 * the already-present BSS ("b") is a hidden SSID beacon for 498 * the new BSS ("a"). 499 */ 500 501 /* sort missing IE before (left of) present IE */ 502 if (!ie1) 503 return -1; 504 if (!ie2) 505 return 1; 506 507 switch (mode) { 508 case BSS_CMP_HIDE_ZLEN: 509 /* 510 * In ZLEN mode we assume the BSS entry we're 511 * looking for has a zero-length SSID. So if 512 * the one we're looking at right now has that, 513 * return 0. Otherwise, return the difference 514 * in length, but since we're looking for the 515 * 0-length it's really equivalent to returning 516 * the length of the one we're looking at. 517 * 518 * No content comparison is needed as we assume 519 * the content length is zero. 520 */ 521 return ie2[1]; 522 case BSS_CMP_REGULAR: 523 default: 524 /* sort by length first, then by contents */ 525 if (ie1[1] != ie2[1]) 526 return ie2[1] - ie1[1]; 527 return memcmp(ie1 + 2, ie2 + 2, ie1[1]); 528 case BSS_CMP_HIDE_NUL: 529 if (ie1[1] != ie2[1]) 530 return ie2[1] - ie1[1]; 531 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */ 532 for (i = 0; i < ie2[1]; i++) 533 if (ie2[i + 2]) 534 return -1; 535 return 0; 536 } 537 } 538 539 static bool cfg80211_bss_type_match(u16 capability, 540 enum nl80211_band band, 541 enum ieee80211_bss_type bss_type) 542 { 543 bool ret = true; 544 u16 mask, val; 545 546 if (bss_type == IEEE80211_BSS_TYPE_ANY) 547 return ret; 548 549 if (band == NL80211_BAND_60GHZ) { 550 mask = WLAN_CAPABILITY_DMG_TYPE_MASK; 551 switch (bss_type) { 552 case IEEE80211_BSS_TYPE_ESS: 553 val = WLAN_CAPABILITY_DMG_TYPE_AP; 554 break; 555 case IEEE80211_BSS_TYPE_PBSS: 556 val = WLAN_CAPABILITY_DMG_TYPE_PBSS; 557 break; 558 case IEEE80211_BSS_TYPE_IBSS: 559 val = WLAN_CAPABILITY_DMG_TYPE_IBSS; 560 break; 561 default: 562 return false; 563 } 564 } else { 565 mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS; 566 switch (bss_type) { 567 case IEEE80211_BSS_TYPE_ESS: 568 val = WLAN_CAPABILITY_ESS; 569 break; 570 case IEEE80211_BSS_TYPE_IBSS: 571 val = WLAN_CAPABILITY_IBSS; 572 break; 573 case IEEE80211_BSS_TYPE_MBSS: 574 val = 0; 575 break; 576 default: 577 return false; 578 } 579 } 580 581 ret = ((capability & mask) == val); 582 return ret; 583 } 584 585 /* Returned bss is reference counted and must be cleaned up appropriately. */ 586 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy, 587 struct ieee80211_channel *channel, 588 const u8 *bssid, 589 const u8 *ssid, size_t ssid_len, 590 enum ieee80211_bss_type bss_type, 591 enum ieee80211_privacy privacy) 592 { 593 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 594 struct cfg80211_internal_bss *bss, *res = NULL; 595 unsigned long now = jiffies; 596 int bss_privacy; 597 598 trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type, 599 privacy); 600 601 spin_lock_bh(&rdev->bss_lock); 602 603 list_for_each_entry(bss, &rdev->bss_list, list) { 604 if (!cfg80211_bss_type_match(bss->pub.capability, 605 bss->pub.channel->band, bss_type)) 606 continue; 607 608 bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY); 609 if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) || 610 (privacy == IEEE80211_PRIVACY_OFF && bss_privacy)) 611 continue; 612 if (channel && bss->pub.channel != channel) 613 continue; 614 if (!is_valid_ether_addr(bss->pub.bssid)) 615 continue; 616 /* Don't get expired BSS structs */ 617 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) && 618 !atomic_read(&bss->hold)) 619 continue; 620 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) { 621 res = bss; 622 bss_ref_get(rdev, res); 623 break; 624 } 625 } 626 627 spin_unlock_bh(&rdev->bss_lock); 628 if (!res) 629 return NULL; 630 trace_cfg80211_return_bss(&res->pub); 631 return &res->pub; 632 } 633 EXPORT_SYMBOL(cfg80211_get_bss); 634 635 static void rb_insert_bss(struct cfg80211_registered_device *rdev, 636 struct cfg80211_internal_bss *bss) 637 { 638 struct rb_node **p = &rdev->bss_tree.rb_node; 639 struct rb_node *parent = NULL; 640 struct cfg80211_internal_bss *tbss; 641 int cmp; 642 643 while (*p) { 644 parent = *p; 645 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn); 646 647 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR); 648 649 if (WARN_ON(!cmp)) { 650 /* will sort of leak this BSS */ 651 return; 652 } 653 654 if (cmp < 0) 655 p = &(*p)->rb_left; 656 else 657 p = &(*p)->rb_right; 658 } 659 660 rb_link_node(&bss->rbn, parent, p); 661 rb_insert_color(&bss->rbn, &rdev->bss_tree); 662 } 663 664 static struct cfg80211_internal_bss * 665 rb_find_bss(struct cfg80211_registered_device *rdev, 666 struct cfg80211_internal_bss *res, 667 enum bss_compare_mode mode) 668 { 669 struct rb_node *n = rdev->bss_tree.rb_node; 670 struct cfg80211_internal_bss *bss; 671 int r; 672 673 while (n) { 674 bss = rb_entry(n, struct cfg80211_internal_bss, rbn); 675 r = cmp_bss(&res->pub, &bss->pub, mode); 676 677 if (r == 0) 678 return bss; 679 else if (r < 0) 680 n = n->rb_left; 681 else 682 n = n->rb_right; 683 } 684 685 return NULL; 686 } 687 688 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev, 689 struct cfg80211_internal_bss *new) 690 { 691 const struct cfg80211_bss_ies *ies; 692 struct cfg80211_internal_bss *bss; 693 const u8 *ie; 694 int i, ssidlen; 695 u8 fold = 0; 696 697 ies = rcu_access_pointer(new->pub.beacon_ies); 698 if (WARN_ON(!ies)) 699 return false; 700 701 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 702 if (!ie) { 703 /* nothing to do */ 704 return true; 705 } 706 707 ssidlen = ie[1]; 708 for (i = 0; i < ssidlen; i++) 709 fold |= ie[2 + i]; 710 711 if (fold) { 712 /* not a hidden SSID */ 713 return true; 714 } 715 716 /* This is the bad part ... */ 717 718 list_for_each_entry(bss, &rdev->bss_list, list) { 719 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid)) 720 continue; 721 if (bss->pub.channel != new->pub.channel) 722 continue; 723 if (bss->pub.scan_width != new->pub.scan_width) 724 continue; 725 if (rcu_access_pointer(bss->pub.beacon_ies)) 726 continue; 727 ies = rcu_access_pointer(bss->pub.ies); 728 if (!ies) 729 continue; 730 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 731 if (!ie) 732 continue; 733 if (ssidlen && ie[1] != ssidlen) 734 continue; 735 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss)) 736 continue; 737 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list))) 738 list_del(&bss->hidden_list); 739 /* combine them */ 740 list_add(&bss->hidden_list, &new->hidden_list); 741 bss->pub.hidden_beacon_bss = &new->pub; 742 new->refcount += bss->refcount; 743 rcu_assign_pointer(bss->pub.beacon_ies, 744 new->pub.beacon_ies); 745 } 746 747 return true; 748 } 749 750 /* Returned bss is reference counted and must be cleaned up appropriately. */ 751 static struct cfg80211_internal_bss * 752 cfg80211_bss_update(struct cfg80211_registered_device *rdev, 753 struct cfg80211_internal_bss *tmp, 754 bool signal_valid) 755 { 756 struct cfg80211_internal_bss *found = NULL; 757 758 if (WARN_ON(!tmp->pub.channel)) 759 return NULL; 760 761 tmp->ts = jiffies; 762 763 spin_lock_bh(&rdev->bss_lock); 764 765 if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) { 766 spin_unlock_bh(&rdev->bss_lock); 767 return NULL; 768 } 769 770 found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR); 771 772 if (found) { 773 /* Update IEs */ 774 if (rcu_access_pointer(tmp->pub.proberesp_ies)) { 775 const struct cfg80211_bss_ies *old; 776 777 old = rcu_access_pointer(found->pub.proberesp_ies); 778 779 rcu_assign_pointer(found->pub.proberesp_ies, 780 tmp->pub.proberesp_ies); 781 /* Override possible earlier Beacon frame IEs */ 782 rcu_assign_pointer(found->pub.ies, 783 tmp->pub.proberesp_ies); 784 if (old) 785 kfree_rcu((struct cfg80211_bss_ies *)old, 786 rcu_head); 787 } else if (rcu_access_pointer(tmp->pub.beacon_ies)) { 788 const struct cfg80211_bss_ies *old; 789 struct cfg80211_internal_bss *bss; 790 791 if (found->pub.hidden_beacon_bss && 792 !list_empty(&found->hidden_list)) { 793 const struct cfg80211_bss_ies *f; 794 795 /* 796 * The found BSS struct is one of the probe 797 * response members of a group, but we're 798 * receiving a beacon (beacon_ies in the tmp 799 * bss is used). This can only mean that the 800 * AP changed its beacon from not having an 801 * SSID to showing it, which is confusing so 802 * drop this information. 803 */ 804 805 f = rcu_access_pointer(tmp->pub.beacon_ies); 806 kfree_rcu((struct cfg80211_bss_ies *)f, 807 rcu_head); 808 goto drop; 809 } 810 811 old = rcu_access_pointer(found->pub.beacon_ies); 812 813 rcu_assign_pointer(found->pub.beacon_ies, 814 tmp->pub.beacon_ies); 815 816 /* Override IEs if they were from a beacon before */ 817 if (old == rcu_access_pointer(found->pub.ies)) 818 rcu_assign_pointer(found->pub.ies, 819 tmp->pub.beacon_ies); 820 821 /* Assign beacon IEs to all sub entries */ 822 list_for_each_entry(bss, &found->hidden_list, 823 hidden_list) { 824 const struct cfg80211_bss_ies *ies; 825 826 ies = rcu_access_pointer(bss->pub.beacon_ies); 827 WARN_ON(ies != old); 828 829 rcu_assign_pointer(bss->pub.beacon_ies, 830 tmp->pub.beacon_ies); 831 } 832 833 if (old) 834 kfree_rcu((struct cfg80211_bss_ies *)old, 835 rcu_head); 836 } 837 838 found->pub.beacon_interval = tmp->pub.beacon_interval; 839 /* 840 * don't update the signal if beacon was heard on 841 * adjacent channel. 842 */ 843 if (signal_valid) 844 found->pub.signal = tmp->pub.signal; 845 found->pub.capability = tmp->pub.capability; 846 found->ts = tmp->ts; 847 found->ts_boottime = tmp->ts_boottime; 848 found->parent_tsf = tmp->parent_tsf; 849 ether_addr_copy(found->parent_bssid, tmp->parent_bssid); 850 } else { 851 struct cfg80211_internal_bss *new; 852 struct cfg80211_internal_bss *hidden; 853 struct cfg80211_bss_ies *ies; 854 855 /* 856 * create a copy -- the "res" variable that is passed in 857 * is allocated on the stack since it's not needed in the 858 * more common case of an update 859 */ 860 new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size, 861 GFP_ATOMIC); 862 if (!new) { 863 ies = (void *)rcu_dereference(tmp->pub.beacon_ies); 864 if (ies) 865 kfree_rcu(ies, rcu_head); 866 ies = (void *)rcu_dereference(tmp->pub.proberesp_ies); 867 if (ies) 868 kfree_rcu(ies, rcu_head); 869 goto drop; 870 } 871 memcpy(new, tmp, sizeof(*new)); 872 new->refcount = 1; 873 INIT_LIST_HEAD(&new->hidden_list); 874 875 if (rcu_access_pointer(tmp->pub.proberesp_ies)) { 876 hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN); 877 if (!hidden) 878 hidden = rb_find_bss(rdev, tmp, 879 BSS_CMP_HIDE_NUL); 880 if (hidden) { 881 new->pub.hidden_beacon_bss = &hidden->pub; 882 list_add(&new->hidden_list, 883 &hidden->hidden_list); 884 hidden->refcount++; 885 rcu_assign_pointer(new->pub.beacon_ies, 886 hidden->pub.beacon_ies); 887 } 888 } else { 889 /* 890 * Ok so we found a beacon, and don't have an entry. If 891 * it's a beacon with hidden SSID, we might be in for an 892 * expensive search for any probe responses that should 893 * be grouped with this beacon for updates ... 894 */ 895 if (!cfg80211_combine_bsses(rdev, new)) { 896 kfree(new); 897 goto drop; 898 } 899 } 900 901 list_add_tail(&new->list, &rdev->bss_list); 902 rb_insert_bss(rdev, new); 903 found = new; 904 } 905 906 rdev->bss_generation++; 907 bss_ref_get(rdev, found); 908 spin_unlock_bh(&rdev->bss_lock); 909 910 return found; 911 drop: 912 spin_unlock_bh(&rdev->bss_lock); 913 return NULL; 914 } 915 916 static struct ieee80211_channel * 917 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen, 918 struct ieee80211_channel *channel) 919 { 920 const u8 *tmp; 921 u32 freq; 922 int channel_number = -1; 923 924 tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen); 925 if (tmp && tmp[1] == 1) { 926 channel_number = tmp[2]; 927 } else { 928 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen); 929 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) { 930 struct ieee80211_ht_operation *htop = (void *)(tmp + 2); 931 932 channel_number = htop->primary_chan; 933 } 934 } 935 936 if (channel_number < 0) 937 return channel; 938 939 freq = ieee80211_channel_to_frequency(channel_number, channel->band); 940 channel = ieee80211_get_channel(wiphy, freq); 941 if (!channel) 942 return NULL; 943 if (channel->flags & IEEE80211_CHAN_DISABLED) 944 return NULL; 945 return channel; 946 } 947 948 /* Returned bss is reference counted and must be cleaned up appropriately. */ 949 struct cfg80211_bss * 950 cfg80211_inform_bss_data(struct wiphy *wiphy, 951 struct cfg80211_inform_bss *data, 952 enum cfg80211_bss_frame_type ftype, 953 const u8 *bssid, u64 tsf, u16 capability, 954 u16 beacon_interval, const u8 *ie, size_t ielen, 955 gfp_t gfp) 956 { 957 struct cfg80211_bss_ies *ies; 958 struct ieee80211_channel *channel; 959 struct cfg80211_internal_bss tmp = {}, *res; 960 int bss_type; 961 bool signal_valid; 962 963 if (WARN_ON(!wiphy)) 964 return NULL; 965 966 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC && 967 (data->signal < 0 || data->signal > 100))) 968 return NULL; 969 970 channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan); 971 if (!channel) 972 return NULL; 973 974 memcpy(tmp.pub.bssid, bssid, ETH_ALEN); 975 tmp.pub.channel = channel; 976 tmp.pub.scan_width = data->scan_width; 977 tmp.pub.signal = data->signal; 978 tmp.pub.beacon_interval = beacon_interval; 979 tmp.pub.capability = capability; 980 tmp.ts_boottime = data->boottime_ns; 981 982 /* 983 * If we do not know here whether the IEs are from a Beacon or Probe 984 * Response frame, we need to pick one of the options and only use it 985 * with the driver that does not provide the full Beacon/Probe Response 986 * frame. Use Beacon frame pointer to avoid indicating that this should 987 * override the IEs pointer should we have received an earlier 988 * indication of Probe Response data. 989 */ 990 ies = kzalloc(sizeof(*ies) + ielen, gfp); 991 if (!ies) 992 return NULL; 993 ies->len = ielen; 994 ies->tsf = tsf; 995 ies->from_beacon = false; 996 memcpy(ies->data, ie, ielen); 997 998 switch (ftype) { 999 case CFG80211_BSS_FTYPE_BEACON: 1000 ies->from_beacon = true; 1001 /* fall through to assign */ 1002 case CFG80211_BSS_FTYPE_UNKNOWN: 1003 rcu_assign_pointer(tmp.pub.beacon_ies, ies); 1004 break; 1005 case CFG80211_BSS_FTYPE_PRESP: 1006 rcu_assign_pointer(tmp.pub.proberesp_ies, ies); 1007 break; 1008 } 1009 rcu_assign_pointer(tmp.pub.ies, ies); 1010 1011 signal_valid = abs(data->chan->center_freq - channel->center_freq) <= 1012 wiphy->max_adj_channel_rssi_comp; 1013 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid); 1014 if (!res) 1015 return NULL; 1016 1017 if (channel->band == NL80211_BAND_60GHZ) { 1018 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK; 1019 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP || 1020 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS) 1021 regulatory_hint_found_beacon(wiphy, channel, gfp); 1022 } else { 1023 if (res->pub.capability & WLAN_CAPABILITY_ESS) 1024 regulatory_hint_found_beacon(wiphy, channel, gfp); 1025 } 1026 1027 trace_cfg80211_return_bss(&res->pub); 1028 /* cfg80211_bss_update gives us a referenced result */ 1029 return &res->pub; 1030 } 1031 EXPORT_SYMBOL(cfg80211_inform_bss_data); 1032 1033 /* cfg80211_inform_bss_width_frame helper */ 1034 struct cfg80211_bss * 1035 cfg80211_inform_bss_frame_data(struct wiphy *wiphy, 1036 struct cfg80211_inform_bss *data, 1037 struct ieee80211_mgmt *mgmt, size_t len, 1038 gfp_t gfp) 1039 1040 { 1041 struct cfg80211_internal_bss tmp = {}, *res; 1042 struct cfg80211_bss_ies *ies; 1043 struct ieee80211_channel *channel; 1044 bool signal_valid; 1045 size_t ielen = len - offsetof(struct ieee80211_mgmt, 1046 u.probe_resp.variable); 1047 int bss_type; 1048 1049 BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) != 1050 offsetof(struct ieee80211_mgmt, u.beacon.variable)); 1051 1052 trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len); 1053 1054 if (WARN_ON(!mgmt)) 1055 return NULL; 1056 1057 if (WARN_ON(!wiphy)) 1058 return NULL; 1059 1060 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC && 1061 (data->signal < 0 || data->signal > 100))) 1062 return NULL; 1063 1064 if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable))) 1065 return NULL; 1066 1067 channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable, 1068 ielen, data->chan); 1069 if (!channel) 1070 return NULL; 1071 1072 ies = kzalloc(sizeof(*ies) + ielen, gfp); 1073 if (!ies) 1074 return NULL; 1075 ies->len = ielen; 1076 ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp); 1077 ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control); 1078 memcpy(ies->data, mgmt->u.probe_resp.variable, ielen); 1079 1080 if (ieee80211_is_probe_resp(mgmt->frame_control)) 1081 rcu_assign_pointer(tmp.pub.proberesp_ies, ies); 1082 else 1083 rcu_assign_pointer(tmp.pub.beacon_ies, ies); 1084 rcu_assign_pointer(tmp.pub.ies, ies); 1085 1086 memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN); 1087 tmp.pub.channel = channel; 1088 tmp.pub.scan_width = data->scan_width; 1089 tmp.pub.signal = data->signal; 1090 tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int); 1091 tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info); 1092 tmp.ts_boottime = data->boottime_ns; 1093 tmp.parent_tsf = data->parent_tsf; 1094 ether_addr_copy(tmp.parent_bssid, data->parent_bssid); 1095 1096 signal_valid = abs(data->chan->center_freq - channel->center_freq) <= 1097 wiphy->max_adj_channel_rssi_comp; 1098 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid); 1099 if (!res) 1100 return NULL; 1101 1102 if (channel->band == NL80211_BAND_60GHZ) { 1103 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK; 1104 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP || 1105 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS) 1106 regulatory_hint_found_beacon(wiphy, channel, gfp); 1107 } else { 1108 if (res->pub.capability & WLAN_CAPABILITY_ESS) 1109 regulatory_hint_found_beacon(wiphy, channel, gfp); 1110 } 1111 1112 trace_cfg80211_return_bss(&res->pub); 1113 /* cfg80211_bss_update gives us a referenced result */ 1114 return &res->pub; 1115 } 1116 EXPORT_SYMBOL(cfg80211_inform_bss_frame_data); 1117 1118 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 1119 { 1120 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1121 struct cfg80211_internal_bss *bss; 1122 1123 if (!pub) 1124 return; 1125 1126 bss = container_of(pub, struct cfg80211_internal_bss, pub); 1127 1128 spin_lock_bh(&rdev->bss_lock); 1129 bss_ref_get(rdev, bss); 1130 spin_unlock_bh(&rdev->bss_lock); 1131 } 1132 EXPORT_SYMBOL(cfg80211_ref_bss); 1133 1134 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 1135 { 1136 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1137 struct cfg80211_internal_bss *bss; 1138 1139 if (!pub) 1140 return; 1141 1142 bss = container_of(pub, struct cfg80211_internal_bss, pub); 1143 1144 spin_lock_bh(&rdev->bss_lock); 1145 bss_ref_put(rdev, bss); 1146 spin_unlock_bh(&rdev->bss_lock); 1147 } 1148 EXPORT_SYMBOL(cfg80211_put_bss); 1149 1150 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 1151 { 1152 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1153 struct cfg80211_internal_bss *bss; 1154 1155 if (WARN_ON(!pub)) 1156 return; 1157 1158 bss = container_of(pub, struct cfg80211_internal_bss, pub); 1159 1160 spin_lock_bh(&rdev->bss_lock); 1161 if (!list_empty(&bss->list)) { 1162 if (__cfg80211_unlink_bss(rdev, bss)) 1163 rdev->bss_generation++; 1164 } 1165 spin_unlock_bh(&rdev->bss_lock); 1166 } 1167 EXPORT_SYMBOL(cfg80211_unlink_bss); 1168 1169 #ifdef CONFIG_CFG80211_WEXT 1170 static struct cfg80211_registered_device * 1171 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex) 1172 { 1173 struct cfg80211_registered_device *rdev; 1174 struct net_device *dev; 1175 1176 ASSERT_RTNL(); 1177 1178 dev = dev_get_by_index(net, ifindex); 1179 if (!dev) 1180 return ERR_PTR(-ENODEV); 1181 if (dev->ieee80211_ptr) 1182 rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy); 1183 else 1184 rdev = ERR_PTR(-ENODEV); 1185 dev_put(dev); 1186 return rdev; 1187 } 1188 1189 int cfg80211_wext_siwscan(struct net_device *dev, 1190 struct iw_request_info *info, 1191 union iwreq_data *wrqu, char *extra) 1192 { 1193 struct cfg80211_registered_device *rdev; 1194 struct wiphy *wiphy; 1195 struct iw_scan_req *wreq = NULL; 1196 struct cfg80211_scan_request *creq = NULL; 1197 int i, err, n_channels = 0; 1198 enum nl80211_band band; 1199 1200 if (!netif_running(dev)) 1201 return -ENETDOWN; 1202 1203 if (wrqu->data.length == sizeof(struct iw_scan_req)) 1204 wreq = (struct iw_scan_req *)extra; 1205 1206 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex); 1207 1208 if (IS_ERR(rdev)) 1209 return PTR_ERR(rdev); 1210 1211 if (rdev->scan_req || rdev->scan_msg) { 1212 err = -EBUSY; 1213 goto out; 1214 } 1215 1216 wiphy = &rdev->wiphy; 1217 1218 /* Determine number of channels, needed to allocate creq */ 1219 if (wreq && wreq->num_channels) 1220 n_channels = wreq->num_channels; 1221 else 1222 n_channels = ieee80211_get_num_supported_channels(wiphy); 1223 1224 creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) + 1225 n_channels * sizeof(void *), 1226 GFP_ATOMIC); 1227 if (!creq) { 1228 err = -ENOMEM; 1229 goto out; 1230 } 1231 1232 creq->wiphy = wiphy; 1233 creq->wdev = dev->ieee80211_ptr; 1234 /* SSIDs come after channels */ 1235 creq->ssids = (void *)&creq->channels[n_channels]; 1236 creq->n_channels = n_channels; 1237 creq->n_ssids = 1; 1238 creq->scan_start = jiffies; 1239 1240 /* translate "Scan on frequencies" request */ 1241 i = 0; 1242 for (band = 0; band < NUM_NL80211_BANDS; band++) { 1243 int j; 1244 1245 if (!wiphy->bands[band]) 1246 continue; 1247 1248 for (j = 0; j < wiphy->bands[band]->n_channels; j++) { 1249 /* ignore disabled channels */ 1250 if (wiphy->bands[band]->channels[j].flags & 1251 IEEE80211_CHAN_DISABLED) 1252 continue; 1253 1254 /* If we have a wireless request structure and the 1255 * wireless request specifies frequencies, then search 1256 * for the matching hardware channel. 1257 */ 1258 if (wreq && wreq->num_channels) { 1259 int k; 1260 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq; 1261 for (k = 0; k < wreq->num_channels; k++) { 1262 struct iw_freq *freq = 1263 &wreq->channel_list[k]; 1264 int wext_freq = 1265 cfg80211_wext_freq(freq); 1266 1267 if (wext_freq == wiphy_freq) 1268 goto wext_freq_found; 1269 } 1270 goto wext_freq_not_found; 1271 } 1272 1273 wext_freq_found: 1274 creq->channels[i] = &wiphy->bands[band]->channels[j]; 1275 i++; 1276 wext_freq_not_found: ; 1277 } 1278 } 1279 /* No channels found? */ 1280 if (!i) { 1281 err = -EINVAL; 1282 goto out; 1283 } 1284 1285 /* Set real number of channels specified in creq->channels[] */ 1286 creq->n_channels = i; 1287 1288 /* translate "Scan for SSID" request */ 1289 if (wreq) { 1290 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) { 1291 if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) { 1292 err = -EINVAL; 1293 goto out; 1294 } 1295 memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len); 1296 creq->ssids[0].ssid_len = wreq->essid_len; 1297 } 1298 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE) 1299 creq->n_ssids = 0; 1300 } 1301 1302 for (i = 0; i < NUM_NL80211_BANDS; i++) 1303 if (wiphy->bands[i]) 1304 creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1; 1305 1306 eth_broadcast_addr(creq->bssid); 1307 1308 rdev->scan_req = creq; 1309 err = rdev_scan(rdev, creq); 1310 if (err) { 1311 rdev->scan_req = NULL; 1312 /* creq will be freed below */ 1313 } else { 1314 nl80211_send_scan_start(rdev, dev->ieee80211_ptr); 1315 /* creq now owned by driver */ 1316 creq = NULL; 1317 dev_hold(dev); 1318 } 1319 out: 1320 kfree(creq); 1321 return err; 1322 } 1323 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan); 1324 1325 static char *ieee80211_scan_add_ies(struct iw_request_info *info, 1326 const struct cfg80211_bss_ies *ies, 1327 char *current_ev, char *end_buf) 1328 { 1329 const u8 *pos, *end, *next; 1330 struct iw_event iwe; 1331 1332 if (!ies) 1333 return current_ev; 1334 1335 /* 1336 * If needed, fragment the IEs buffer (at IE boundaries) into short 1337 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages. 1338 */ 1339 pos = ies->data; 1340 end = pos + ies->len; 1341 1342 while (end - pos > IW_GENERIC_IE_MAX) { 1343 next = pos + 2 + pos[1]; 1344 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX) 1345 next = next + 2 + next[1]; 1346 1347 memset(&iwe, 0, sizeof(iwe)); 1348 iwe.cmd = IWEVGENIE; 1349 iwe.u.data.length = next - pos; 1350 current_ev = iwe_stream_add_point_check(info, current_ev, 1351 end_buf, &iwe, 1352 (void *)pos); 1353 if (IS_ERR(current_ev)) 1354 return current_ev; 1355 pos = next; 1356 } 1357 1358 if (end > pos) { 1359 memset(&iwe, 0, sizeof(iwe)); 1360 iwe.cmd = IWEVGENIE; 1361 iwe.u.data.length = end - pos; 1362 current_ev = iwe_stream_add_point_check(info, current_ev, 1363 end_buf, &iwe, 1364 (void *)pos); 1365 if (IS_ERR(current_ev)) 1366 return current_ev; 1367 } 1368 1369 return current_ev; 1370 } 1371 1372 static char * 1373 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info, 1374 struct cfg80211_internal_bss *bss, char *current_ev, 1375 char *end_buf) 1376 { 1377 const struct cfg80211_bss_ies *ies; 1378 struct iw_event iwe; 1379 const u8 *ie; 1380 u8 buf[50]; 1381 u8 *cfg, *p, *tmp; 1382 int rem, i, sig; 1383 bool ismesh = false; 1384 1385 memset(&iwe, 0, sizeof(iwe)); 1386 iwe.cmd = SIOCGIWAP; 1387 iwe.u.ap_addr.sa_family = ARPHRD_ETHER; 1388 memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN); 1389 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 1390 IW_EV_ADDR_LEN); 1391 if (IS_ERR(current_ev)) 1392 return current_ev; 1393 1394 memset(&iwe, 0, sizeof(iwe)); 1395 iwe.cmd = SIOCGIWFREQ; 1396 iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq); 1397 iwe.u.freq.e = 0; 1398 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 1399 IW_EV_FREQ_LEN); 1400 if (IS_ERR(current_ev)) 1401 return current_ev; 1402 1403 memset(&iwe, 0, sizeof(iwe)); 1404 iwe.cmd = SIOCGIWFREQ; 1405 iwe.u.freq.m = bss->pub.channel->center_freq; 1406 iwe.u.freq.e = 6; 1407 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 1408 IW_EV_FREQ_LEN); 1409 if (IS_ERR(current_ev)) 1410 return current_ev; 1411 1412 if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) { 1413 memset(&iwe, 0, sizeof(iwe)); 1414 iwe.cmd = IWEVQUAL; 1415 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED | 1416 IW_QUAL_NOISE_INVALID | 1417 IW_QUAL_QUAL_UPDATED; 1418 switch (wiphy->signal_type) { 1419 case CFG80211_SIGNAL_TYPE_MBM: 1420 sig = bss->pub.signal / 100; 1421 iwe.u.qual.level = sig; 1422 iwe.u.qual.updated |= IW_QUAL_DBM; 1423 if (sig < -110) /* rather bad */ 1424 sig = -110; 1425 else if (sig > -40) /* perfect */ 1426 sig = -40; 1427 /* will give a range of 0 .. 70 */ 1428 iwe.u.qual.qual = sig + 110; 1429 break; 1430 case CFG80211_SIGNAL_TYPE_UNSPEC: 1431 iwe.u.qual.level = bss->pub.signal; 1432 /* will give range 0 .. 100 */ 1433 iwe.u.qual.qual = bss->pub.signal; 1434 break; 1435 default: 1436 /* not reached */ 1437 break; 1438 } 1439 current_ev = iwe_stream_add_event_check(info, current_ev, 1440 end_buf, &iwe, 1441 IW_EV_QUAL_LEN); 1442 if (IS_ERR(current_ev)) 1443 return current_ev; 1444 } 1445 1446 memset(&iwe, 0, sizeof(iwe)); 1447 iwe.cmd = SIOCGIWENCODE; 1448 if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY) 1449 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY; 1450 else 1451 iwe.u.data.flags = IW_ENCODE_DISABLED; 1452 iwe.u.data.length = 0; 1453 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf, 1454 &iwe, ""); 1455 if (IS_ERR(current_ev)) 1456 return current_ev; 1457 1458 rcu_read_lock(); 1459 ies = rcu_dereference(bss->pub.ies); 1460 rem = ies->len; 1461 ie = ies->data; 1462 1463 while (rem >= 2) { 1464 /* invalid data */ 1465 if (ie[1] > rem - 2) 1466 break; 1467 1468 switch (ie[0]) { 1469 case WLAN_EID_SSID: 1470 memset(&iwe, 0, sizeof(iwe)); 1471 iwe.cmd = SIOCGIWESSID; 1472 iwe.u.data.length = ie[1]; 1473 iwe.u.data.flags = 1; 1474 current_ev = iwe_stream_add_point_check(info, 1475 current_ev, 1476 end_buf, &iwe, 1477 (u8 *)ie + 2); 1478 if (IS_ERR(current_ev)) 1479 goto unlock; 1480 break; 1481 case WLAN_EID_MESH_ID: 1482 memset(&iwe, 0, sizeof(iwe)); 1483 iwe.cmd = SIOCGIWESSID; 1484 iwe.u.data.length = ie[1]; 1485 iwe.u.data.flags = 1; 1486 current_ev = iwe_stream_add_point_check(info, 1487 current_ev, 1488 end_buf, &iwe, 1489 (u8 *)ie + 2); 1490 if (IS_ERR(current_ev)) 1491 goto unlock; 1492 break; 1493 case WLAN_EID_MESH_CONFIG: 1494 ismesh = true; 1495 if (ie[1] != sizeof(struct ieee80211_meshconf_ie)) 1496 break; 1497 cfg = (u8 *)ie + 2; 1498 memset(&iwe, 0, sizeof(iwe)); 1499 iwe.cmd = IWEVCUSTOM; 1500 sprintf(buf, "Mesh Network Path Selection Protocol ID: " 1501 "0x%02X", cfg[0]); 1502 iwe.u.data.length = strlen(buf); 1503 current_ev = iwe_stream_add_point_check(info, 1504 current_ev, 1505 end_buf, 1506 &iwe, buf); 1507 if (IS_ERR(current_ev)) 1508 goto unlock; 1509 sprintf(buf, "Path Selection Metric ID: 0x%02X", 1510 cfg[1]); 1511 iwe.u.data.length = strlen(buf); 1512 current_ev = iwe_stream_add_point_check(info, 1513 current_ev, 1514 end_buf, 1515 &iwe, buf); 1516 if (IS_ERR(current_ev)) 1517 goto unlock; 1518 sprintf(buf, "Congestion Control Mode ID: 0x%02X", 1519 cfg[2]); 1520 iwe.u.data.length = strlen(buf); 1521 current_ev = iwe_stream_add_point_check(info, 1522 current_ev, 1523 end_buf, 1524 &iwe, buf); 1525 if (IS_ERR(current_ev)) 1526 goto unlock; 1527 sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]); 1528 iwe.u.data.length = strlen(buf); 1529 current_ev = iwe_stream_add_point_check(info, 1530 current_ev, 1531 end_buf, 1532 &iwe, buf); 1533 if (IS_ERR(current_ev)) 1534 goto unlock; 1535 sprintf(buf, "Authentication ID: 0x%02X", cfg[4]); 1536 iwe.u.data.length = strlen(buf); 1537 current_ev = iwe_stream_add_point_check(info, 1538 current_ev, 1539 end_buf, 1540 &iwe, buf); 1541 if (IS_ERR(current_ev)) 1542 goto unlock; 1543 sprintf(buf, "Formation Info: 0x%02X", cfg[5]); 1544 iwe.u.data.length = strlen(buf); 1545 current_ev = iwe_stream_add_point_check(info, 1546 current_ev, 1547 end_buf, 1548 &iwe, buf); 1549 if (IS_ERR(current_ev)) 1550 goto unlock; 1551 sprintf(buf, "Capabilities: 0x%02X", cfg[6]); 1552 iwe.u.data.length = strlen(buf); 1553 current_ev = iwe_stream_add_point_check(info, 1554 current_ev, 1555 end_buf, 1556 &iwe, buf); 1557 if (IS_ERR(current_ev)) 1558 goto unlock; 1559 break; 1560 case WLAN_EID_SUPP_RATES: 1561 case WLAN_EID_EXT_SUPP_RATES: 1562 /* display all supported rates in readable format */ 1563 p = current_ev + iwe_stream_lcp_len(info); 1564 1565 memset(&iwe, 0, sizeof(iwe)); 1566 iwe.cmd = SIOCGIWRATE; 1567 /* Those two flags are ignored... */ 1568 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0; 1569 1570 for (i = 0; i < ie[1]; i++) { 1571 iwe.u.bitrate.value = 1572 ((ie[i + 2] & 0x7f) * 500000); 1573 tmp = p; 1574 p = iwe_stream_add_value(info, current_ev, p, 1575 end_buf, &iwe, 1576 IW_EV_PARAM_LEN); 1577 if (p == tmp) { 1578 current_ev = ERR_PTR(-E2BIG); 1579 goto unlock; 1580 } 1581 } 1582 current_ev = p; 1583 break; 1584 } 1585 rem -= ie[1] + 2; 1586 ie += ie[1] + 2; 1587 } 1588 1589 if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) || 1590 ismesh) { 1591 memset(&iwe, 0, sizeof(iwe)); 1592 iwe.cmd = SIOCGIWMODE; 1593 if (ismesh) 1594 iwe.u.mode = IW_MODE_MESH; 1595 else if (bss->pub.capability & WLAN_CAPABILITY_ESS) 1596 iwe.u.mode = IW_MODE_MASTER; 1597 else 1598 iwe.u.mode = IW_MODE_ADHOC; 1599 current_ev = iwe_stream_add_event_check(info, current_ev, 1600 end_buf, &iwe, 1601 IW_EV_UINT_LEN); 1602 if (IS_ERR(current_ev)) 1603 goto unlock; 1604 } 1605 1606 memset(&iwe, 0, sizeof(iwe)); 1607 iwe.cmd = IWEVCUSTOM; 1608 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf)); 1609 iwe.u.data.length = strlen(buf); 1610 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf, 1611 &iwe, buf); 1612 if (IS_ERR(current_ev)) 1613 goto unlock; 1614 memset(&iwe, 0, sizeof(iwe)); 1615 iwe.cmd = IWEVCUSTOM; 1616 sprintf(buf, " Last beacon: %ums ago", 1617 elapsed_jiffies_msecs(bss->ts)); 1618 iwe.u.data.length = strlen(buf); 1619 current_ev = iwe_stream_add_point_check(info, current_ev, 1620 end_buf, &iwe, buf); 1621 if (IS_ERR(current_ev)) 1622 goto unlock; 1623 1624 current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf); 1625 1626 unlock: 1627 rcu_read_unlock(); 1628 return current_ev; 1629 } 1630 1631 1632 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev, 1633 struct iw_request_info *info, 1634 char *buf, size_t len) 1635 { 1636 char *current_ev = buf; 1637 char *end_buf = buf + len; 1638 struct cfg80211_internal_bss *bss; 1639 int err = 0; 1640 1641 spin_lock_bh(&rdev->bss_lock); 1642 cfg80211_bss_expire(rdev); 1643 1644 list_for_each_entry(bss, &rdev->bss_list, list) { 1645 if (buf + len - current_ev <= IW_EV_ADDR_LEN) { 1646 err = -E2BIG; 1647 break; 1648 } 1649 current_ev = ieee80211_bss(&rdev->wiphy, info, bss, 1650 current_ev, end_buf); 1651 if (IS_ERR(current_ev)) { 1652 err = PTR_ERR(current_ev); 1653 break; 1654 } 1655 } 1656 spin_unlock_bh(&rdev->bss_lock); 1657 1658 if (err) 1659 return err; 1660 return current_ev - buf; 1661 } 1662 1663 1664 int cfg80211_wext_giwscan(struct net_device *dev, 1665 struct iw_request_info *info, 1666 struct iw_point *data, char *extra) 1667 { 1668 struct cfg80211_registered_device *rdev; 1669 int res; 1670 1671 if (!netif_running(dev)) 1672 return -ENETDOWN; 1673 1674 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex); 1675 1676 if (IS_ERR(rdev)) 1677 return PTR_ERR(rdev); 1678 1679 if (rdev->scan_req || rdev->scan_msg) 1680 return -EAGAIN; 1681 1682 res = ieee80211_scan_results(rdev, info, extra, data->length); 1683 data->length = 0; 1684 if (res >= 0) { 1685 data->length = res; 1686 res = 0; 1687 } 1688 1689 return res; 1690 } 1691 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan); 1692 #endif 1693