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 = 270 jiffies + msecs_to_jiffies(request->interval); 271 } 272 nl80211_send_sched_scan_results(rdev, request->dev); 273 } 274 275 rtnl_unlock(); 276 } 277 278 void cfg80211_sched_scan_results(struct wiphy *wiphy) 279 { 280 trace_cfg80211_sched_scan_results(wiphy); 281 /* ignore if we're not scanning */ 282 283 if (rcu_access_pointer(wiphy_to_rdev(wiphy)->sched_scan_req)) 284 queue_work(cfg80211_wq, 285 &wiphy_to_rdev(wiphy)->sched_scan_results_wk); 286 } 287 EXPORT_SYMBOL(cfg80211_sched_scan_results); 288 289 void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy) 290 { 291 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 292 293 ASSERT_RTNL(); 294 295 trace_cfg80211_sched_scan_stopped(wiphy); 296 297 __cfg80211_stop_sched_scan(rdev, true); 298 } 299 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_rtnl); 300 301 void cfg80211_sched_scan_stopped(struct wiphy *wiphy) 302 { 303 rtnl_lock(); 304 cfg80211_sched_scan_stopped_rtnl(wiphy); 305 rtnl_unlock(); 306 } 307 EXPORT_SYMBOL(cfg80211_sched_scan_stopped); 308 309 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev, 310 bool driver_initiated) 311 { 312 struct cfg80211_sched_scan_request *sched_scan_req; 313 struct net_device *dev; 314 315 ASSERT_RTNL(); 316 317 if (!rdev->sched_scan_req) 318 return -ENOENT; 319 320 sched_scan_req = rtnl_dereference(rdev->sched_scan_req); 321 dev = sched_scan_req->dev; 322 323 if (!driver_initiated) { 324 int err = rdev_sched_scan_stop(rdev, dev); 325 if (err) 326 return err; 327 } 328 329 nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED); 330 331 RCU_INIT_POINTER(rdev->sched_scan_req, NULL); 332 kfree_rcu(sched_scan_req, rcu_head); 333 334 return 0; 335 } 336 337 void cfg80211_bss_age(struct cfg80211_registered_device *rdev, 338 unsigned long age_secs) 339 { 340 struct cfg80211_internal_bss *bss; 341 unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC); 342 343 spin_lock_bh(&rdev->bss_lock); 344 list_for_each_entry(bss, &rdev->bss_list, list) 345 bss->ts -= age_jiffies; 346 spin_unlock_bh(&rdev->bss_lock); 347 } 348 349 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev) 350 { 351 __cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE); 352 } 353 354 const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len) 355 { 356 while (len > 2 && ies[0] != eid) { 357 len -= ies[1] + 2; 358 ies += ies[1] + 2; 359 } 360 if (len < 2) 361 return NULL; 362 if (len < 2 + ies[1]) 363 return NULL; 364 return ies; 365 } 366 EXPORT_SYMBOL(cfg80211_find_ie); 367 368 const u8 *cfg80211_find_vendor_ie(unsigned int oui, u8 oui_type, 369 const u8 *ies, int len) 370 { 371 struct ieee80211_vendor_ie *ie; 372 const u8 *pos = ies, *end = ies + len; 373 int ie_oui; 374 375 while (pos < end) { 376 pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos, 377 end - pos); 378 if (!pos) 379 return NULL; 380 381 ie = (struct ieee80211_vendor_ie *)pos; 382 383 /* make sure we can access ie->len */ 384 BUILD_BUG_ON(offsetof(struct ieee80211_vendor_ie, len) != 1); 385 386 if (ie->len < sizeof(*ie)) 387 goto cont; 388 389 ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2]; 390 if (ie_oui == oui && ie->oui_type == oui_type) 391 return pos; 392 cont: 393 pos += 2 + ie->len; 394 } 395 return NULL; 396 } 397 EXPORT_SYMBOL(cfg80211_find_vendor_ie); 398 399 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid, 400 const u8 *ssid, size_t ssid_len) 401 { 402 const struct cfg80211_bss_ies *ies; 403 const u8 *ssidie; 404 405 if (bssid && !ether_addr_equal(a->bssid, bssid)) 406 return false; 407 408 if (!ssid) 409 return true; 410 411 ies = rcu_access_pointer(a->ies); 412 if (!ies) 413 return false; 414 ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 415 if (!ssidie) 416 return false; 417 if (ssidie[1] != ssid_len) 418 return false; 419 return memcmp(ssidie + 2, ssid, ssid_len) == 0; 420 } 421 422 /** 423 * enum bss_compare_mode - BSS compare mode 424 * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find) 425 * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode 426 * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode 427 */ 428 enum bss_compare_mode { 429 BSS_CMP_REGULAR, 430 BSS_CMP_HIDE_ZLEN, 431 BSS_CMP_HIDE_NUL, 432 }; 433 434 static int cmp_bss(struct cfg80211_bss *a, 435 struct cfg80211_bss *b, 436 enum bss_compare_mode mode) 437 { 438 const struct cfg80211_bss_ies *a_ies, *b_ies; 439 const u8 *ie1 = NULL; 440 const u8 *ie2 = NULL; 441 int i, r; 442 443 if (a->channel != b->channel) 444 return b->channel->center_freq - a->channel->center_freq; 445 446 a_ies = rcu_access_pointer(a->ies); 447 if (!a_ies) 448 return -1; 449 b_ies = rcu_access_pointer(b->ies); 450 if (!b_ies) 451 return 1; 452 453 if (WLAN_CAPABILITY_IS_STA_BSS(a->capability)) 454 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID, 455 a_ies->data, a_ies->len); 456 if (WLAN_CAPABILITY_IS_STA_BSS(b->capability)) 457 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID, 458 b_ies->data, b_ies->len); 459 if (ie1 && ie2) { 460 int mesh_id_cmp; 461 462 if (ie1[1] == ie2[1]) 463 mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]); 464 else 465 mesh_id_cmp = ie2[1] - ie1[1]; 466 467 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, 468 a_ies->data, a_ies->len); 469 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, 470 b_ies->data, b_ies->len); 471 if (ie1 && ie2) { 472 if (mesh_id_cmp) 473 return mesh_id_cmp; 474 if (ie1[1] != ie2[1]) 475 return ie2[1] - ie1[1]; 476 return memcmp(ie1 + 2, ie2 + 2, ie1[1]); 477 } 478 } 479 480 r = memcmp(a->bssid, b->bssid, sizeof(a->bssid)); 481 if (r) 482 return r; 483 484 ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len); 485 ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len); 486 487 if (!ie1 && !ie2) 488 return 0; 489 490 /* 491 * Note that with "hide_ssid", the function returns a match if 492 * the already-present BSS ("b") is a hidden SSID beacon for 493 * the new BSS ("a"). 494 */ 495 496 /* sort missing IE before (left of) present IE */ 497 if (!ie1) 498 return -1; 499 if (!ie2) 500 return 1; 501 502 switch (mode) { 503 case BSS_CMP_HIDE_ZLEN: 504 /* 505 * In ZLEN mode we assume the BSS entry we're 506 * looking for has a zero-length SSID. So if 507 * the one we're looking at right now has that, 508 * return 0. Otherwise, return the difference 509 * in length, but since we're looking for the 510 * 0-length it's really equivalent to returning 511 * the length of the one we're looking at. 512 * 513 * No content comparison is needed as we assume 514 * the content length is zero. 515 */ 516 return ie2[1]; 517 case BSS_CMP_REGULAR: 518 default: 519 /* sort by length first, then by contents */ 520 if (ie1[1] != ie2[1]) 521 return ie2[1] - ie1[1]; 522 return memcmp(ie1 + 2, ie2 + 2, ie1[1]); 523 case BSS_CMP_HIDE_NUL: 524 if (ie1[1] != ie2[1]) 525 return ie2[1] - ie1[1]; 526 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */ 527 for (i = 0; i < ie2[1]; i++) 528 if (ie2[i + 2]) 529 return -1; 530 return 0; 531 } 532 } 533 534 static bool cfg80211_bss_type_match(u16 capability, 535 enum ieee80211_band band, 536 enum ieee80211_bss_type bss_type) 537 { 538 bool ret = true; 539 u16 mask, val; 540 541 if (bss_type == IEEE80211_BSS_TYPE_ANY) 542 return ret; 543 544 if (band == IEEE80211_BAND_60GHZ) { 545 mask = WLAN_CAPABILITY_DMG_TYPE_MASK; 546 switch (bss_type) { 547 case IEEE80211_BSS_TYPE_ESS: 548 val = WLAN_CAPABILITY_DMG_TYPE_AP; 549 break; 550 case IEEE80211_BSS_TYPE_PBSS: 551 val = WLAN_CAPABILITY_DMG_TYPE_PBSS; 552 break; 553 case IEEE80211_BSS_TYPE_IBSS: 554 val = WLAN_CAPABILITY_DMG_TYPE_IBSS; 555 break; 556 default: 557 return false; 558 } 559 } else { 560 mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS; 561 switch (bss_type) { 562 case IEEE80211_BSS_TYPE_ESS: 563 val = WLAN_CAPABILITY_ESS; 564 break; 565 case IEEE80211_BSS_TYPE_IBSS: 566 val = WLAN_CAPABILITY_IBSS; 567 break; 568 case IEEE80211_BSS_TYPE_MBSS: 569 val = 0; 570 break; 571 default: 572 return false; 573 } 574 } 575 576 ret = ((capability & mask) == val); 577 return ret; 578 } 579 580 /* Returned bss is reference counted and must be cleaned up appropriately. */ 581 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy, 582 struct ieee80211_channel *channel, 583 const u8 *bssid, 584 const u8 *ssid, size_t ssid_len, 585 enum ieee80211_bss_type bss_type, 586 enum ieee80211_privacy privacy) 587 { 588 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 589 struct cfg80211_internal_bss *bss, *res = NULL; 590 unsigned long now = jiffies; 591 int bss_privacy; 592 593 trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type, 594 privacy); 595 596 spin_lock_bh(&rdev->bss_lock); 597 598 list_for_each_entry(bss, &rdev->bss_list, list) { 599 if (!cfg80211_bss_type_match(bss->pub.capability, 600 bss->pub.channel->band, bss_type)) 601 continue; 602 603 bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY); 604 if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) || 605 (privacy == IEEE80211_PRIVACY_OFF && bss_privacy)) 606 continue; 607 if (channel && bss->pub.channel != channel) 608 continue; 609 if (!is_valid_ether_addr(bss->pub.bssid)) 610 continue; 611 /* Don't get expired BSS structs */ 612 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) && 613 !atomic_read(&bss->hold)) 614 continue; 615 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) { 616 res = bss; 617 bss_ref_get(rdev, res); 618 break; 619 } 620 } 621 622 spin_unlock_bh(&rdev->bss_lock); 623 if (!res) 624 return NULL; 625 trace_cfg80211_return_bss(&res->pub); 626 return &res->pub; 627 } 628 EXPORT_SYMBOL(cfg80211_get_bss); 629 630 static void rb_insert_bss(struct cfg80211_registered_device *rdev, 631 struct cfg80211_internal_bss *bss) 632 { 633 struct rb_node **p = &rdev->bss_tree.rb_node; 634 struct rb_node *parent = NULL; 635 struct cfg80211_internal_bss *tbss; 636 int cmp; 637 638 while (*p) { 639 parent = *p; 640 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn); 641 642 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR); 643 644 if (WARN_ON(!cmp)) { 645 /* will sort of leak this BSS */ 646 return; 647 } 648 649 if (cmp < 0) 650 p = &(*p)->rb_left; 651 else 652 p = &(*p)->rb_right; 653 } 654 655 rb_link_node(&bss->rbn, parent, p); 656 rb_insert_color(&bss->rbn, &rdev->bss_tree); 657 } 658 659 static struct cfg80211_internal_bss * 660 rb_find_bss(struct cfg80211_registered_device *rdev, 661 struct cfg80211_internal_bss *res, 662 enum bss_compare_mode mode) 663 { 664 struct rb_node *n = rdev->bss_tree.rb_node; 665 struct cfg80211_internal_bss *bss; 666 int r; 667 668 while (n) { 669 bss = rb_entry(n, struct cfg80211_internal_bss, rbn); 670 r = cmp_bss(&res->pub, &bss->pub, mode); 671 672 if (r == 0) 673 return bss; 674 else if (r < 0) 675 n = n->rb_left; 676 else 677 n = n->rb_right; 678 } 679 680 return NULL; 681 } 682 683 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev, 684 struct cfg80211_internal_bss *new) 685 { 686 const struct cfg80211_bss_ies *ies; 687 struct cfg80211_internal_bss *bss; 688 const u8 *ie; 689 int i, ssidlen; 690 u8 fold = 0; 691 692 ies = rcu_access_pointer(new->pub.beacon_ies); 693 if (WARN_ON(!ies)) 694 return false; 695 696 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 697 if (!ie) { 698 /* nothing to do */ 699 return true; 700 } 701 702 ssidlen = ie[1]; 703 for (i = 0; i < ssidlen; i++) 704 fold |= ie[2 + i]; 705 706 if (fold) { 707 /* not a hidden SSID */ 708 return true; 709 } 710 711 /* This is the bad part ... */ 712 713 list_for_each_entry(bss, &rdev->bss_list, list) { 714 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid)) 715 continue; 716 if (bss->pub.channel != new->pub.channel) 717 continue; 718 if (bss->pub.scan_width != new->pub.scan_width) 719 continue; 720 if (rcu_access_pointer(bss->pub.beacon_ies)) 721 continue; 722 ies = rcu_access_pointer(bss->pub.ies); 723 if (!ies) 724 continue; 725 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); 726 if (!ie) 727 continue; 728 if (ssidlen && ie[1] != ssidlen) 729 continue; 730 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss)) 731 continue; 732 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list))) 733 list_del(&bss->hidden_list); 734 /* combine them */ 735 list_add(&bss->hidden_list, &new->hidden_list); 736 bss->pub.hidden_beacon_bss = &new->pub; 737 new->refcount += bss->refcount; 738 rcu_assign_pointer(bss->pub.beacon_ies, 739 new->pub.beacon_ies); 740 } 741 742 return true; 743 } 744 745 /* Returned bss is reference counted and must be cleaned up appropriately. */ 746 static struct cfg80211_internal_bss * 747 cfg80211_bss_update(struct cfg80211_registered_device *rdev, 748 struct cfg80211_internal_bss *tmp, 749 bool signal_valid) 750 { 751 struct cfg80211_internal_bss *found = NULL; 752 753 if (WARN_ON(!tmp->pub.channel)) 754 return NULL; 755 756 tmp->ts = jiffies; 757 758 spin_lock_bh(&rdev->bss_lock); 759 760 if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) { 761 spin_unlock_bh(&rdev->bss_lock); 762 return NULL; 763 } 764 765 found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR); 766 767 if (found) { 768 /* Update IEs */ 769 if (rcu_access_pointer(tmp->pub.proberesp_ies)) { 770 const struct cfg80211_bss_ies *old; 771 772 old = rcu_access_pointer(found->pub.proberesp_ies); 773 774 rcu_assign_pointer(found->pub.proberesp_ies, 775 tmp->pub.proberesp_ies); 776 /* Override possible earlier Beacon frame IEs */ 777 rcu_assign_pointer(found->pub.ies, 778 tmp->pub.proberesp_ies); 779 if (old) 780 kfree_rcu((struct cfg80211_bss_ies *)old, 781 rcu_head); 782 } else if (rcu_access_pointer(tmp->pub.beacon_ies)) { 783 const struct cfg80211_bss_ies *old; 784 struct cfg80211_internal_bss *bss; 785 786 if (found->pub.hidden_beacon_bss && 787 !list_empty(&found->hidden_list)) { 788 const struct cfg80211_bss_ies *f; 789 790 /* 791 * The found BSS struct is one of the probe 792 * response members of a group, but we're 793 * receiving a beacon (beacon_ies in the tmp 794 * bss is used). This can only mean that the 795 * AP changed its beacon from not having an 796 * SSID to showing it, which is confusing so 797 * drop this information. 798 */ 799 800 f = rcu_access_pointer(tmp->pub.beacon_ies); 801 kfree_rcu((struct cfg80211_bss_ies *)f, 802 rcu_head); 803 goto drop; 804 } 805 806 old = rcu_access_pointer(found->pub.beacon_ies); 807 808 rcu_assign_pointer(found->pub.beacon_ies, 809 tmp->pub.beacon_ies); 810 811 /* Override IEs if they were from a beacon before */ 812 if (old == rcu_access_pointer(found->pub.ies)) 813 rcu_assign_pointer(found->pub.ies, 814 tmp->pub.beacon_ies); 815 816 /* Assign beacon IEs to all sub entries */ 817 list_for_each_entry(bss, &found->hidden_list, 818 hidden_list) { 819 const struct cfg80211_bss_ies *ies; 820 821 ies = rcu_access_pointer(bss->pub.beacon_ies); 822 WARN_ON(ies != old); 823 824 rcu_assign_pointer(bss->pub.beacon_ies, 825 tmp->pub.beacon_ies); 826 } 827 828 if (old) 829 kfree_rcu((struct cfg80211_bss_ies *)old, 830 rcu_head); 831 } 832 833 found->pub.beacon_interval = tmp->pub.beacon_interval; 834 /* 835 * don't update the signal if beacon was heard on 836 * adjacent channel. 837 */ 838 if (signal_valid) 839 found->pub.signal = tmp->pub.signal; 840 found->pub.capability = tmp->pub.capability; 841 found->ts = tmp->ts; 842 } else { 843 struct cfg80211_internal_bss *new; 844 struct cfg80211_internal_bss *hidden; 845 struct cfg80211_bss_ies *ies; 846 847 /* 848 * create a copy -- the "res" variable that is passed in 849 * is allocated on the stack since it's not needed in the 850 * more common case of an update 851 */ 852 new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size, 853 GFP_ATOMIC); 854 if (!new) { 855 ies = (void *)rcu_dereference(tmp->pub.beacon_ies); 856 if (ies) 857 kfree_rcu(ies, rcu_head); 858 ies = (void *)rcu_dereference(tmp->pub.proberesp_ies); 859 if (ies) 860 kfree_rcu(ies, rcu_head); 861 goto drop; 862 } 863 memcpy(new, tmp, sizeof(*new)); 864 new->refcount = 1; 865 INIT_LIST_HEAD(&new->hidden_list); 866 867 if (rcu_access_pointer(tmp->pub.proberesp_ies)) { 868 hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN); 869 if (!hidden) 870 hidden = rb_find_bss(rdev, tmp, 871 BSS_CMP_HIDE_NUL); 872 if (hidden) { 873 new->pub.hidden_beacon_bss = &hidden->pub; 874 list_add(&new->hidden_list, 875 &hidden->hidden_list); 876 hidden->refcount++; 877 rcu_assign_pointer(new->pub.beacon_ies, 878 hidden->pub.beacon_ies); 879 } 880 } else { 881 /* 882 * Ok so we found a beacon, and don't have an entry. If 883 * it's a beacon with hidden SSID, we might be in for an 884 * expensive search for any probe responses that should 885 * be grouped with this beacon for updates ... 886 */ 887 if (!cfg80211_combine_bsses(rdev, new)) { 888 kfree(new); 889 goto drop; 890 } 891 } 892 893 list_add_tail(&new->list, &rdev->bss_list); 894 rb_insert_bss(rdev, new); 895 found = new; 896 } 897 898 rdev->bss_generation++; 899 bss_ref_get(rdev, found); 900 spin_unlock_bh(&rdev->bss_lock); 901 902 return found; 903 drop: 904 spin_unlock_bh(&rdev->bss_lock); 905 return NULL; 906 } 907 908 static struct ieee80211_channel * 909 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen, 910 struct ieee80211_channel *channel) 911 { 912 const u8 *tmp; 913 u32 freq; 914 int channel_number = -1; 915 916 tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen); 917 if (tmp && tmp[1] == 1) { 918 channel_number = tmp[2]; 919 } else { 920 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen); 921 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) { 922 struct ieee80211_ht_operation *htop = (void *)(tmp + 2); 923 924 channel_number = htop->primary_chan; 925 } 926 } 927 928 if (channel_number < 0) 929 return channel; 930 931 freq = ieee80211_channel_to_frequency(channel_number, channel->band); 932 channel = ieee80211_get_channel(wiphy, freq); 933 if (!channel) 934 return NULL; 935 if (channel->flags & IEEE80211_CHAN_DISABLED) 936 return NULL; 937 return channel; 938 } 939 940 /* Returned bss is reference counted and must be cleaned up appropriately. */ 941 struct cfg80211_bss* 942 cfg80211_inform_bss_width(struct wiphy *wiphy, 943 struct ieee80211_channel *rx_channel, 944 enum nl80211_bss_scan_width scan_width, 945 enum cfg80211_bss_frame_type ftype, 946 const u8 *bssid, u64 tsf, u16 capability, 947 u16 beacon_interval, const u8 *ie, size_t ielen, 948 s32 signal, gfp_t gfp) 949 { 950 struct cfg80211_bss_ies *ies; 951 struct ieee80211_channel *channel; 952 struct cfg80211_internal_bss tmp = {}, *res; 953 int bss_type; 954 bool signal_valid; 955 956 if (WARN_ON(!wiphy)) 957 return NULL; 958 959 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC && 960 (signal < 0 || signal > 100))) 961 return NULL; 962 963 channel = cfg80211_get_bss_channel(wiphy, ie, ielen, rx_channel); 964 if (!channel) 965 return NULL; 966 967 memcpy(tmp.pub.bssid, bssid, ETH_ALEN); 968 tmp.pub.channel = channel; 969 tmp.pub.scan_width = scan_width; 970 tmp.pub.signal = signal; 971 tmp.pub.beacon_interval = beacon_interval; 972 tmp.pub.capability = capability; 973 /* 974 * If we do not know here whether the IEs are from a Beacon or Probe 975 * Response frame, we need to pick one of the options and only use it 976 * with the driver that does not provide the full Beacon/Probe Response 977 * frame. Use Beacon frame pointer to avoid indicating that this should 978 * override the IEs pointer should we have received an earlier 979 * indication of Probe Response data. 980 */ 981 ies = kzalloc(sizeof(*ies) + ielen, gfp); 982 if (!ies) 983 return NULL; 984 ies->len = ielen; 985 ies->tsf = tsf; 986 ies->from_beacon = false; 987 memcpy(ies->data, ie, ielen); 988 989 switch (ftype) { 990 case CFG80211_BSS_FTYPE_BEACON: 991 ies->from_beacon = true; 992 /* fall through to assign */ 993 case CFG80211_BSS_FTYPE_UNKNOWN: 994 rcu_assign_pointer(tmp.pub.beacon_ies, ies); 995 break; 996 case CFG80211_BSS_FTYPE_PRESP: 997 rcu_assign_pointer(tmp.pub.proberesp_ies, ies); 998 break; 999 } 1000 rcu_assign_pointer(tmp.pub.ies, ies); 1001 1002 signal_valid = abs(rx_channel->center_freq - channel->center_freq) <= 1003 wiphy->max_adj_channel_rssi_comp; 1004 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid); 1005 if (!res) 1006 return NULL; 1007 1008 if (channel->band == IEEE80211_BAND_60GHZ) { 1009 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK; 1010 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP || 1011 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS) 1012 regulatory_hint_found_beacon(wiphy, channel, gfp); 1013 } else { 1014 if (res->pub.capability & WLAN_CAPABILITY_ESS) 1015 regulatory_hint_found_beacon(wiphy, channel, gfp); 1016 } 1017 1018 trace_cfg80211_return_bss(&res->pub); 1019 /* cfg80211_bss_update gives us a referenced result */ 1020 return &res->pub; 1021 } 1022 EXPORT_SYMBOL(cfg80211_inform_bss_width); 1023 1024 /* Returned bss is reference counted and must be cleaned up appropriately. */ 1025 struct cfg80211_bss * 1026 cfg80211_inform_bss_width_frame(struct wiphy *wiphy, 1027 struct ieee80211_channel *rx_channel, 1028 enum nl80211_bss_scan_width scan_width, 1029 struct ieee80211_mgmt *mgmt, size_t len, 1030 s32 signal, gfp_t gfp) 1031 { 1032 struct cfg80211_internal_bss tmp = {}, *res; 1033 struct cfg80211_bss_ies *ies; 1034 struct ieee80211_channel *channel; 1035 bool signal_valid; 1036 size_t ielen = len - offsetof(struct ieee80211_mgmt, 1037 u.probe_resp.variable); 1038 int bss_type; 1039 1040 BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) != 1041 offsetof(struct ieee80211_mgmt, u.beacon.variable)); 1042 1043 trace_cfg80211_inform_bss_width_frame(wiphy, rx_channel, scan_width, mgmt, 1044 len, signal); 1045 1046 if (WARN_ON(!mgmt)) 1047 return NULL; 1048 1049 if (WARN_ON(!wiphy)) 1050 return NULL; 1051 1052 if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC && 1053 (signal < 0 || signal > 100))) 1054 return NULL; 1055 1056 if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable))) 1057 return NULL; 1058 1059 channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable, 1060 ielen, rx_channel); 1061 if (!channel) 1062 return NULL; 1063 1064 ies = kzalloc(sizeof(*ies) + ielen, gfp); 1065 if (!ies) 1066 return NULL; 1067 ies->len = ielen; 1068 ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp); 1069 ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control); 1070 memcpy(ies->data, mgmt->u.probe_resp.variable, ielen); 1071 1072 if (ieee80211_is_probe_resp(mgmt->frame_control)) 1073 rcu_assign_pointer(tmp.pub.proberesp_ies, ies); 1074 else 1075 rcu_assign_pointer(tmp.pub.beacon_ies, ies); 1076 rcu_assign_pointer(tmp.pub.ies, ies); 1077 1078 memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN); 1079 tmp.pub.channel = channel; 1080 tmp.pub.scan_width = scan_width; 1081 tmp.pub.signal = signal; 1082 tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int); 1083 tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info); 1084 1085 signal_valid = abs(rx_channel->center_freq - channel->center_freq) <= 1086 wiphy->max_adj_channel_rssi_comp; 1087 res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid); 1088 if (!res) 1089 return NULL; 1090 1091 if (channel->band == IEEE80211_BAND_60GHZ) { 1092 bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK; 1093 if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP || 1094 bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS) 1095 regulatory_hint_found_beacon(wiphy, channel, gfp); 1096 } else { 1097 if (res->pub.capability & WLAN_CAPABILITY_ESS) 1098 regulatory_hint_found_beacon(wiphy, channel, gfp); 1099 } 1100 1101 trace_cfg80211_return_bss(&res->pub); 1102 /* cfg80211_bss_update gives us a referenced result */ 1103 return &res->pub; 1104 } 1105 EXPORT_SYMBOL(cfg80211_inform_bss_width_frame); 1106 1107 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 1108 { 1109 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1110 struct cfg80211_internal_bss *bss; 1111 1112 if (!pub) 1113 return; 1114 1115 bss = container_of(pub, struct cfg80211_internal_bss, pub); 1116 1117 spin_lock_bh(&rdev->bss_lock); 1118 bss_ref_get(rdev, bss); 1119 spin_unlock_bh(&rdev->bss_lock); 1120 } 1121 EXPORT_SYMBOL(cfg80211_ref_bss); 1122 1123 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 1124 { 1125 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1126 struct cfg80211_internal_bss *bss; 1127 1128 if (!pub) 1129 return; 1130 1131 bss = container_of(pub, struct cfg80211_internal_bss, pub); 1132 1133 spin_lock_bh(&rdev->bss_lock); 1134 bss_ref_put(rdev, bss); 1135 spin_unlock_bh(&rdev->bss_lock); 1136 } 1137 EXPORT_SYMBOL(cfg80211_put_bss); 1138 1139 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) 1140 { 1141 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); 1142 struct cfg80211_internal_bss *bss; 1143 1144 if (WARN_ON(!pub)) 1145 return; 1146 1147 bss = container_of(pub, struct cfg80211_internal_bss, pub); 1148 1149 spin_lock_bh(&rdev->bss_lock); 1150 if (!list_empty(&bss->list)) { 1151 if (__cfg80211_unlink_bss(rdev, bss)) 1152 rdev->bss_generation++; 1153 } 1154 spin_unlock_bh(&rdev->bss_lock); 1155 } 1156 EXPORT_SYMBOL(cfg80211_unlink_bss); 1157 1158 #ifdef CONFIG_CFG80211_WEXT 1159 static struct cfg80211_registered_device * 1160 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex) 1161 { 1162 struct cfg80211_registered_device *rdev; 1163 struct net_device *dev; 1164 1165 ASSERT_RTNL(); 1166 1167 dev = dev_get_by_index(net, ifindex); 1168 if (!dev) 1169 return ERR_PTR(-ENODEV); 1170 if (dev->ieee80211_ptr) 1171 rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy); 1172 else 1173 rdev = ERR_PTR(-ENODEV); 1174 dev_put(dev); 1175 return rdev; 1176 } 1177 1178 int cfg80211_wext_siwscan(struct net_device *dev, 1179 struct iw_request_info *info, 1180 union iwreq_data *wrqu, char *extra) 1181 { 1182 struct cfg80211_registered_device *rdev; 1183 struct wiphy *wiphy; 1184 struct iw_scan_req *wreq = NULL; 1185 struct cfg80211_scan_request *creq = NULL; 1186 int i, err, n_channels = 0; 1187 enum ieee80211_band band; 1188 1189 if (!netif_running(dev)) 1190 return -ENETDOWN; 1191 1192 if (wrqu->data.length == sizeof(struct iw_scan_req)) 1193 wreq = (struct iw_scan_req *)extra; 1194 1195 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex); 1196 1197 if (IS_ERR(rdev)) 1198 return PTR_ERR(rdev); 1199 1200 if (rdev->scan_req || rdev->scan_msg) { 1201 err = -EBUSY; 1202 goto out; 1203 } 1204 1205 wiphy = &rdev->wiphy; 1206 1207 /* Determine number of channels, needed to allocate creq */ 1208 if (wreq && wreq->num_channels) 1209 n_channels = wreq->num_channels; 1210 else 1211 n_channels = ieee80211_get_num_supported_channels(wiphy); 1212 1213 creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) + 1214 n_channels * sizeof(void *), 1215 GFP_ATOMIC); 1216 if (!creq) { 1217 err = -ENOMEM; 1218 goto out; 1219 } 1220 1221 creq->wiphy = wiphy; 1222 creq->wdev = dev->ieee80211_ptr; 1223 /* SSIDs come after channels */ 1224 creq->ssids = (void *)&creq->channels[n_channels]; 1225 creq->n_channels = n_channels; 1226 creq->n_ssids = 1; 1227 creq->scan_start = jiffies; 1228 1229 /* translate "Scan on frequencies" request */ 1230 i = 0; 1231 for (band = 0; band < IEEE80211_NUM_BANDS; band++) { 1232 int j; 1233 1234 if (!wiphy->bands[band]) 1235 continue; 1236 1237 for (j = 0; j < wiphy->bands[band]->n_channels; j++) { 1238 /* ignore disabled channels */ 1239 if (wiphy->bands[band]->channels[j].flags & 1240 IEEE80211_CHAN_DISABLED) 1241 continue; 1242 1243 /* If we have a wireless request structure and the 1244 * wireless request specifies frequencies, then search 1245 * for the matching hardware channel. 1246 */ 1247 if (wreq && wreq->num_channels) { 1248 int k; 1249 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq; 1250 for (k = 0; k < wreq->num_channels; k++) { 1251 struct iw_freq *freq = 1252 &wreq->channel_list[k]; 1253 int wext_freq = 1254 cfg80211_wext_freq(freq); 1255 1256 if (wext_freq == wiphy_freq) 1257 goto wext_freq_found; 1258 } 1259 goto wext_freq_not_found; 1260 } 1261 1262 wext_freq_found: 1263 creq->channels[i] = &wiphy->bands[band]->channels[j]; 1264 i++; 1265 wext_freq_not_found: ; 1266 } 1267 } 1268 /* No channels found? */ 1269 if (!i) { 1270 err = -EINVAL; 1271 goto out; 1272 } 1273 1274 /* Set real number of channels specified in creq->channels[] */ 1275 creq->n_channels = i; 1276 1277 /* translate "Scan for SSID" request */ 1278 if (wreq) { 1279 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) { 1280 if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) { 1281 err = -EINVAL; 1282 goto out; 1283 } 1284 memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len); 1285 creq->ssids[0].ssid_len = wreq->essid_len; 1286 } 1287 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE) 1288 creq->n_ssids = 0; 1289 } 1290 1291 for (i = 0; i < IEEE80211_NUM_BANDS; i++) 1292 if (wiphy->bands[i]) 1293 creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1; 1294 1295 rdev->scan_req = creq; 1296 err = rdev_scan(rdev, creq); 1297 if (err) { 1298 rdev->scan_req = NULL; 1299 /* creq will be freed below */ 1300 } else { 1301 nl80211_send_scan_start(rdev, dev->ieee80211_ptr); 1302 /* creq now owned by driver */ 1303 creq = NULL; 1304 dev_hold(dev); 1305 } 1306 out: 1307 kfree(creq); 1308 return err; 1309 } 1310 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan); 1311 1312 static char *ieee80211_scan_add_ies(struct iw_request_info *info, 1313 const struct cfg80211_bss_ies *ies, 1314 char *current_ev, char *end_buf) 1315 { 1316 const u8 *pos, *end, *next; 1317 struct iw_event iwe; 1318 1319 if (!ies) 1320 return current_ev; 1321 1322 /* 1323 * If needed, fragment the IEs buffer (at IE boundaries) into short 1324 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages. 1325 */ 1326 pos = ies->data; 1327 end = pos + ies->len; 1328 1329 while (end - pos > IW_GENERIC_IE_MAX) { 1330 next = pos + 2 + pos[1]; 1331 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX) 1332 next = next + 2 + next[1]; 1333 1334 memset(&iwe, 0, sizeof(iwe)); 1335 iwe.cmd = IWEVGENIE; 1336 iwe.u.data.length = next - pos; 1337 current_ev = iwe_stream_add_point_check(info, current_ev, 1338 end_buf, &iwe, 1339 (void *)pos); 1340 if (IS_ERR(current_ev)) 1341 return current_ev; 1342 pos = next; 1343 } 1344 1345 if (end > pos) { 1346 memset(&iwe, 0, sizeof(iwe)); 1347 iwe.cmd = IWEVGENIE; 1348 iwe.u.data.length = end - pos; 1349 current_ev = iwe_stream_add_point_check(info, current_ev, 1350 end_buf, &iwe, 1351 (void *)pos); 1352 if (IS_ERR(current_ev)) 1353 return current_ev; 1354 } 1355 1356 return current_ev; 1357 } 1358 1359 static char * 1360 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info, 1361 struct cfg80211_internal_bss *bss, char *current_ev, 1362 char *end_buf) 1363 { 1364 const struct cfg80211_bss_ies *ies; 1365 struct iw_event iwe; 1366 const u8 *ie; 1367 u8 buf[50]; 1368 u8 *cfg, *p, *tmp; 1369 int rem, i, sig; 1370 bool ismesh = false; 1371 1372 memset(&iwe, 0, sizeof(iwe)); 1373 iwe.cmd = SIOCGIWAP; 1374 iwe.u.ap_addr.sa_family = ARPHRD_ETHER; 1375 memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN); 1376 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 1377 IW_EV_ADDR_LEN); 1378 if (IS_ERR(current_ev)) 1379 return current_ev; 1380 1381 memset(&iwe, 0, sizeof(iwe)); 1382 iwe.cmd = SIOCGIWFREQ; 1383 iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq); 1384 iwe.u.freq.e = 0; 1385 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 1386 IW_EV_FREQ_LEN); 1387 if (IS_ERR(current_ev)) 1388 return current_ev; 1389 1390 memset(&iwe, 0, sizeof(iwe)); 1391 iwe.cmd = SIOCGIWFREQ; 1392 iwe.u.freq.m = bss->pub.channel->center_freq; 1393 iwe.u.freq.e = 6; 1394 current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe, 1395 IW_EV_FREQ_LEN); 1396 if (IS_ERR(current_ev)) 1397 return current_ev; 1398 1399 if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) { 1400 memset(&iwe, 0, sizeof(iwe)); 1401 iwe.cmd = IWEVQUAL; 1402 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED | 1403 IW_QUAL_NOISE_INVALID | 1404 IW_QUAL_QUAL_UPDATED; 1405 switch (wiphy->signal_type) { 1406 case CFG80211_SIGNAL_TYPE_MBM: 1407 sig = bss->pub.signal / 100; 1408 iwe.u.qual.level = sig; 1409 iwe.u.qual.updated |= IW_QUAL_DBM; 1410 if (sig < -110) /* rather bad */ 1411 sig = -110; 1412 else if (sig > -40) /* perfect */ 1413 sig = -40; 1414 /* will give a range of 0 .. 70 */ 1415 iwe.u.qual.qual = sig + 110; 1416 break; 1417 case CFG80211_SIGNAL_TYPE_UNSPEC: 1418 iwe.u.qual.level = bss->pub.signal; 1419 /* will give range 0 .. 100 */ 1420 iwe.u.qual.qual = bss->pub.signal; 1421 break; 1422 default: 1423 /* not reached */ 1424 break; 1425 } 1426 current_ev = iwe_stream_add_event_check(info, current_ev, 1427 end_buf, &iwe, 1428 IW_EV_QUAL_LEN); 1429 if (IS_ERR(current_ev)) 1430 return current_ev; 1431 } 1432 1433 memset(&iwe, 0, sizeof(iwe)); 1434 iwe.cmd = SIOCGIWENCODE; 1435 if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY) 1436 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY; 1437 else 1438 iwe.u.data.flags = IW_ENCODE_DISABLED; 1439 iwe.u.data.length = 0; 1440 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf, 1441 &iwe, ""); 1442 if (IS_ERR(current_ev)) 1443 return current_ev; 1444 1445 rcu_read_lock(); 1446 ies = rcu_dereference(bss->pub.ies); 1447 rem = ies->len; 1448 ie = ies->data; 1449 1450 while (rem >= 2) { 1451 /* invalid data */ 1452 if (ie[1] > rem - 2) 1453 break; 1454 1455 switch (ie[0]) { 1456 case WLAN_EID_SSID: 1457 memset(&iwe, 0, sizeof(iwe)); 1458 iwe.cmd = SIOCGIWESSID; 1459 iwe.u.data.length = ie[1]; 1460 iwe.u.data.flags = 1; 1461 current_ev = iwe_stream_add_point_check(info, 1462 current_ev, 1463 end_buf, &iwe, 1464 (u8 *)ie + 2); 1465 if (IS_ERR(current_ev)) 1466 goto unlock; 1467 break; 1468 case WLAN_EID_MESH_ID: 1469 memset(&iwe, 0, sizeof(iwe)); 1470 iwe.cmd = SIOCGIWESSID; 1471 iwe.u.data.length = ie[1]; 1472 iwe.u.data.flags = 1; 1473 current_ev = iwe_stream_add_point_check(info, 1474 current_ev, 1475 end_buf, &iwe, 1476 (u8 *)ie + 2); 1477 if (IS_ERR(current_ev)) 1478 goto unlock; 1479 break; 1480 case WLAN_EID_MESH_CONFIG: 1481 ismesh = true; 1482 if (ie[1] != sizeof(struct ieee80211_meshconf_ie)) 1483 break; 1484 cfg = (u8 *)ie + 2; 1485 memset(&iwe, 0, sizeof(iwe)); 1486 iwe.cmd = IWEVCUSTOM; 1487 sprintf(buf, "Mesh Network Path Selection Protocol ID: " 1488 "0x%02X", cfg[0]); 1489 iwe.u.data.length = strlen(buf); 1490 current_ev = iwe_stream_add_point_check(info, 1491 current_ev, 1492 end_buf, 1493 &iwe, buf); 1494 if (IS_ERR(current_ev)) 1495 goto unlock; 1496 sprintf(buf, "Path Selection Metric ID: 0x%02X", 1497 cfg[1]); 1498 iwe.u.data.length = strlen(buf); 1499 current_ev = iwe_stream_add_point_check(info, 1500 current_ev, 1501 end_buf, 1502 &iwe, buf); 1503 if (IS_ERR(current_ev)) 1504 goto unlock; 1505 sprintf(buf, "Congestion Control Mode ID: 0x%02X", 1506 cfg[2]); 1507 iwe.u.data.length = strlen(buf); 1508 current_ev = iwe_stream_add_point_check(info, 1509 current_ev, 1510 end_buf, 1511 &iwe, buf); 1512 if (IS_ERR(current_ev)) 1513 goto unlock; 1514 sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]); 1515 iwe.u.data.length = strlen(buf); 1516 current_ev = iwe_stream_add_point_check(info, 1517 current_ev, 1518 end_buf, 1519 &iwe, buf); 1520 if (IS_ERR(current_ev)) 1521 goto unlock; 1522 sprintf(buf, "Authentication ID: 0x%02X", cfg[4]); 1523 iwe.u.data.length = strlen(buf); 1524 current_ev = iwe_stream_add_point_check(info, 1525 current_ev, 1526 end_buf, 1527 &iwe, buf); 1528 if (IS_ERR(current_ev)) 1529 goto unlock; 1530 sprintf(buf, "Formation Info: 0x%02X", cfg[5]); 1531 iwe.u.data.length = strlen(buf); 1532 current_ev = iwe_stream_add_point_check(info, 1533 current_ev, 1534 end_buf, 1535 &iwe, buf); 1536 if (IS_ERR(current_ev)) 1537 goto unlock; 1538 sprintf(buf, "Capabilities: 0x%02X", cfg[6]); 1539 iwe.u.data.length = strlen(buf); 1540 current_ev = iwe_stream_add_point_check(info, 1541 current_ev, 1542 end_buf, 1543 &iwe, buf); 1544 if (IS_ERR(current_ev)) 1545 goto unlock; 1546 break; 1547 case WLAN_EID_SUPP_RATES: 1548 case WLAN_EID_EXT_SUPP_RATES: 1549 /* display all supported rates in readable format */ 1550 p = current_ev + iwe_stream_lcp_len(info); 1551 1552 memset(&iwe, 0, sizeof(iwe)); 1553 iwe.cmd = SIOCGIWRATE; 1554 /* Those two flags are ignored... */ 1555 iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0; 1556 1557 for (i = 0; i < ie[1]; i++) { 1558 iwe.u.bitrate.value = 1559 ((ie[i + 2] & 0x7f) * 500000); 1560 tmp = p; 1561 p = iwe_stream_add_value(info, current_ev, p, 1562 end_buf, &iwe, 1563 IW_EV_PARAM_LEN); 1564 if (p == tmp) { 1565 current_ev = ERR_PTR(-E2BIG); 1566 goto unlock; 1567 } 1568 } 1569 current_ev = p; 1570 break; 1571 } 1572 rem -= ie[1] + 2; 1573 ie += ie[1] + 2; 1574 } 1575 1576 if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) || 1577 ismesh) { 1578 memset(&iwe, 0, sizeof(iwe)); 1579 iwe.cmd = SIOCGIWMODE; 1580 if (ismesh) 1581 iwe.u.mode = IW_MODE_MESH; 1582 else if (bss->pub.capability & WLAN_CAPABILITY_ESS) 1583 iwe.u.mode = IW_MODE_MASTER; 1584 else 1585 iwe.u.mode = IW_MODE_ADHOC; 1586 current_ev = iwe_stream_add_event_check(info, current_ev, 1587 end_buf, &iwe, 1588 IW_EV_UINT_LEN); 1589 if (IS_ERR(current_ev)) 1590 goto unlock; 1591 } 1592 1593 memset(&iwe, 0, sizeof(iwe)); 1594 iwe.cmd = IWEVCUSTOM; 1595 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf)); 1596 iwe.u.data.length = strlen(buf); 1597 current_ev = iwe_stream_add_point_check(info, current_ev, end_buf, 1598 &iwe, buf); 1599 if (IS_ERR(current_ev)) 1600 goto unlock; 1601 memset(&iwe, 0, sizeof(iwe)); 1602 iwe.cmd = IWEVCUSTOM; 1603 sprintf(buf, " Last beacon: %ums ago", 1604 elapsed_jiffies_msecs(bss->ts)); 1605 iwe.u.data.length = strlen(buf); 1606 current_ev = iwe_stream_add_point_check(info, current_ev, 1607 end_buf, &iwe, buf); 1608 if (IS_ERR(current_ev)) 1609 goto unlock; 1610 1611 current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf); 1612 1613 unlock: 1614 rcu_read_unlock(); 1615 return current_ev; 1616 } 1617 1618 1619 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev, 1620 struct iw_request_info *info, 1621 char *buf, size_t len) 1622 { 1623 char *current_ev = buf; 1624 char *end_buf = buf + len; 1625 struct cfg80211_internal_bss *bss; 1626 int err = 0; 1627 1628 spin_lock_bh(&rdev->bss_lock); 1629 cfg80211_bss_expire(rdev); 1630 1631 list_for_each_entry(bss, &rdev->bss_list, list) { 1632 if (buf + len - current_ev <= IW_EV_ADDR_LEN) { 1633 err = -E2BIG; 1634 break; 1635 } 1636 current_ev = ieee80211_bss(&rdev->wiphy, info, bss, 1637 current_ev, end_buf); 1638 if (IS_ERR(current_ev)) { 1639 err = PTR_ERR(current_ev); 1640 break; 1641 } 1642 } 1643 spin_unlock_bh(&rdev->bss_lock); 1644 1645 if (err) 1646 return err; 1647 return current_ev - buf; 1648 } 1649 1650 1651 int cfg80211_wext_giwscan(struct net_device *dev, 1652 struct iw_request_info *info, 1653 struct iw_point *data, char *extra) 1654 { 1655 struct cfg80211_registered_device *rdev; 1656 int res; 1657 1658 if (!netif_running(dev)) 1659 return -ENETDOWN; 1660 1661 rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex); 1662 1663 if (IS_ERR(rdev)) 1664 return PTR_ERR(rdev); 1665 1666 if (rdev->scan_req || rdev->scan_msg) 1667 return -EAGAIN; 1668 1669 res = ieee80211_scan_results(rdev, info, extra, data->length); 1670 data->length = 0; 1671 if (res >= 0) { 1672 data->length = res; 1673 res = 0; 1674 } 1675 1676 return res; 1677 } 1678 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan); 1679 #endif 1680