Pileus Git - ~andy/linux/blob - net/wireless/scan.c

   1 /*
   2  * cfg80211 scan result handling
   3  *
   4  * Copyright 2008 Johannes Berg <johannes@sipsolutions.net>
   5  */
   6 #include <linux/kernel.h>
   7 #include <linux/slab.h>
   8 #include <linux/module.h>
   9 #include <linux/netdevice.h>
  10 #include <linux/wireless.h>
  11 #include <linux/nl80211.h>
  12 #include <linux/etherdevice.h>
  13 #include <net/arp.h>
  14 #include <net/cfg80211.h>
  15 #include <net/cfg80211-wext.h>
  16 #include <net/iw_handler.h>
  17 #include "core.h"
  18 #include "nl80211.h"
  19 #include "wext-compat.h"
  20 #include "rdev-ops.h"
  21
  22 /**
  23  * DOC: BSS tree/list structure
  24  *
  25  * At the top level, the BSS list is kept in both a list in each
  26  * registered device (@bss_list) as well as an RB-tree for faster
  27  * lookup. In the RB-tree, entries can be looked up using their
  28  * channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID
  29  * for other BSSes.
  30  *
  31  * Due to the possibility of hidden SSIDs, there's a second level
  32  * structure, the "hidden_list" and "hidden_beacon_bss" pointer.
  33  * The hidden_list connects all BSSes belonging to a single AP
  34  * that has a hidden SSID, and connects beacon and probe response
  35  * entries. For a probe response entry for a hidden SSID, the
  36  * hidden_beacon_bss pointer points to the BSS struct holding the
  37  * beacon's information.
  38  *
  39  * Reference counting is done for all these references except for
  40  * the hidden_list, so that a beacon BSS struct that is otherwise
  41  * not referenced has one reference for being on the bss_list and
  42  * one for each probe response entry that points to it using the
  43  * hidden_beacon_bss pointer. When a BSS struct that has such a
  44  * pointer is get/put, the refcount update is also propagated to
  45  * the referenced struct, this ensure that it cannot get removed
  46  * while somebody is using the probe response version.
  47  *
  48  * Note that the hidden_beacon_bss pointer never changes, due to
  49  * the reference counting. Therefore, no locking is needed for
  50  * it.
  51  *
  52  * Also note that the hidden_beacon_bss pointer is only relevant
  53  * if the driver uses something other than the IEs, e.g. private
  54  * data stored stored in the BSS struct, since the beacon IEs are
  55  * also linked into the probe response struct.
  56  */
  57
  58 #define IEEE80211_SCAN_RESULT_EXPIRE    (30 * HZ)
  59
  60 static void bss_free(struct cfg80211_internal_bss *bss)
  61 {
  62         struct cfg80211_bss_ies *ies;
  63
  64         if (WARN_ON(atomic_read(&bss->hold)))
  65                 return;
  66
  67         ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
  68         if (ies && !bss->pub.hidden_beacon_bss)
  69                 kfree_rcu(ies, rcu_head);
  70         ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
  71         if (ies)
  72                 kfree_rcu(ies, rcu_head);
  73
  74         /*
  75          * This happens when the module is removed, it doesn't
  76          * really matter any more save for completeness
  77          */
  78         if (!list_empty(&bss->hidden_list))
  79                 list_del(&bss->hidden_list);
  80
  81         kfree(bss);
  82 }
  83
  84 static inline void bss_ref_get(struct cfg80211_registered_device *dev,
  85                                struct cfg80211_internal_bss *bss)
  86 {
  87         lockdep_assert_held(&dev->bss_lock);
  88
  89         bss->refcount++;
  90         if (bss->pub.hidden_beacon_bss) {
  91                 bss = container_of(bss->pub.hidden_beacon_bss,
  92                                    struct cfg80211_internal_bss,
  93                                    pub);
  94                 bss->refcount++;
  95         }
  96 }
  97
  98 static inline void bss_ref_put(struct cfg80211_registered_device *dev,
  99                                struct cfg80211_internal_bss *bss)
 100 {
 101         lockdep_assert_held(&dev->bss_lock);
 102
 103         if (bss->pub.hidden_beacon_bss) {
 104                 struct cfg80211_internal_bss *hbss;
 105                 hbss = container_of(bss->pub.hidden_beacon_bss,
 106                                     struct cfg80211_internal_bss,
 107                                     pub);
 108                 hbss->refcount--;
 109                 if (hbss->refcount == 0)
 110                         bss_free(hbss);
 111         }
 112         bss->refcount--;
 113         if (bss->refcount == 0)
 114                 bss_free(bss);
 115 }
 116
 117 static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *dev,
 118                                   struct cfg80211_internal_bss *bss)
 119 {
 120         lockdep_assert_held(&dev->bss_lock);
 121
 122         if (!list_empty(&bss->hidden_list)) {
 123                 /*
 124                  * don't remove the beacon entry if it has
 125                  * probe responses associated with it
 126                  */
 127                 if (!bss->pub.hidden_beacon_bss)
 128                         return false;
 129                 /*
 130                  * if it's a probe response entry break its
 131                  * link to the other entries in the group
 132                  */
 133                 list_del_init(&bss->hidden_list);
 134         }
 135
 136         list_del_init(&bss->list);
 137         rb_erase(&bss->rbn, &dev->bss_tree);
 138         bss_ref_put(dev, bss);
 139         return true;
 140 }
 141
 142 static void __cfg80211_bss_expire(struct cfg80211_registered_device *dev,
 143                                   unsigned long expire_time)
 144 {
 145         struct cfg80211_internal_bss *bss, *tmp;
 146         bool expired = false;
 147
 148         lockdep_assert_held(&dev->bss_lock);
 149
 150         list_for_each_entry_safe(bss, tmp, &dev->bss_list, list) {
 151                 if (atomic_read(&bss->hold))
 152                         continue;
 153                 if (!time_after(expire_time, bss->ts))
 154                         continue;
 155
 156                 if (__cfg80211_unlink_bss(dev, bss))
 157                         expired = true;
 158         }
 159
 160         if (expired)
 161                 dev->bss_generation++;
 162 }
 163
 164 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev)
 165 {
 166         struct cfg80211_scan_request *request;
 167         struct wireless_dev *wdev;
 168 #ifdef CONFIG_CFG80211_WEXT
 169         union iwreq_data wrqu;
 170 #endif
 171
 172         ASSERT_RTNL();
 173
 174         request = rdev->scan_req;
 175
 176         if (!request)
 177                 return;
 178
 179         wdev = request->wdev;
 180
 181         /*
 182          * This must be before sending the other events!
 183          * Otherwise, wpa_supplicant gets completely confused with
 184          * wext events.
 185          */
 186         if (wdev->netdev)
 187                 cfg80211_sme_scan_done(wdev->netdev);
 188
 189         if (request->aborted) {
 190                 nl80211_send_scan_aborted(rdev, wdev);
 191         } else {
 192                 if (request->flags & NL80211_SCAN_FLAG_FLUSH) {
 193                         /* flush entries from previous scans */
 194                         spin_lock_bh(&rdev->bss_lock);
 195                         __cfg80211_bss_expire(rdev, request->scan_start);
 196                         spin_unlock_bh(&rdev->bss_lock);
 197                 }
 198                 nl80211_send_scan_done(rdev, wdev);
 199         }
 200
 201 #ifdef CONFIG_CFG80211_WEXT
 202         if (wdev->netdev && !request->aborted) {
 203                 memset(&wrqu, 0, sizeof(wrqu));
 204
 205                 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
 206         }
 207 #endif
 208
 209         if (wdev->netdev)
 210                 dev_put(wdev->netdev);
 211
 212         rdev->scan_req = NULL;
 213         kfree(request);
 214 }
 215
 216 void __cfg80211_scan_done(struct work_struct *wk)
 217 {
 218         struct cfg80211_registered_device *rdev;
 219
 220         rdev = container_of(wk, struct cfg80211_registered_device,
 221                             scan_done_wk);
 222
 223         rtnl_lock();
 224         ___cfg80211_scan_done(rdev);
 225         rtnl_unlock();
 226 }
 227
 228 void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
 229 {
 230         trace_cfg80211_scan_done(request, aborted);
 231         WARN_ON(request != wiphy_to_dev(request->wiphy)->scan_req);
 232
 233         request->aborted = aborted;
 234         request->notified = true;
 235         queue_work(cfg80211_wq, &wiphy_to_dev(request->wiphy)->scan_done_wk);
 236 }
 237 EXPORT_SYMBOL(cfg80211_scan_done);
 238
 239 void __cfg80211_sched_scan_results(struct work_struct *wk)
 240 {
 241         struct cfg80211_registered_device *rdev;
 242         struct cfg80211_sched_scan_request *request;
 243
 244         rdev = container_of(wk, struct cfg80211_registered_device,
 245                             sched_scan_results_wk);
 246
 247         rtnl_lock();
 248
 249         request = rdev->sched_scan_req;
 250
 251         /* we don't have sched_scan_req anymore if the scan is stopping */
 252         if (request) {
 253                 if (request->flags & NL80211_SCAN_FLAG_FLUSH) {
 254                         /* flush entries from previous scans */
 255                         spin_lock_bh(&rdev->bss_lock);
 256                         __cfg80211_bss_expire(rdev, request->scan_start);
 257                         spin_unlock_bh(&rdev->bss_lock);
 258                         request->scan_start =
 259                                 jiffies + msecs_to_jiffies(request->interval);
 260                 }
 261                 nl80211_send_sched_scan_results(rdev, request->dev);
 262         }
 263
 264         rtnl_unlock();
 265 }
 266
 267 void cfg80211_sched_scan_results(struct wiphy *wiphy)
 268 {
 269         trace_cfg80211_sched_scan_results(wiphy);
 270         /* ignore if we're not scanning */
 271         if (wiphy_to_dev(wiphy)->sched_scan_req)
 272                 queue_work(cfg80211_wq,
 273                            &wiphy_to_dev(wiphy)->sched_scan_results_wk);
 274 }
 275 EXPORT_SYMBOL(cfg80211_sched_scan_results);
 276
 277 void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
 278 {
 279         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
 280
 281         trace_cfg80211_sched_scan_stopped(wiphy);
 282
 283         rtnl_lock();
 284         __cfg80211_stop_sched_scan(rdev, true);
 285         rtnl_unlock();
 286 }
 287 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
 288
 289 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
 290                                bool driver_initiated)
 291 {
 292         struct net_device *dev;
 293
 294         ASSERT_RTNL();
 295
 296         if (!rdev->sched_scan_req)
 297                 return -ENOENT;
 298
 299         dev = rdev->sched_scan_req->dev;
 300
 301         if (!driver_initiated) {
 302                 int err = rdev_sched_scan_stop(rdev, dev);
 303                 if (err)
 304                         return err;
 305         }
 306
 307         nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED);
 308
 309         kfree(rdev->sched_scan_req);
 310         rdev->sched_scan_req = NULL;
 311
 312         return 0;
 313 }
 314
 315 void cfg80211_bss_age(struct cfg80211_registered_device *dev,
 316                       unsigned long age_secs)
 317 {
 318         struct cfg80211_internal_bss *bss;
 319         unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
 320
 321         spin_lock_bh(&dev->bss_lock);
 322         list_for_each_entry(bss, &dev->bss_list, list)
 323                 bss->ts -= age_jiffies;
 324         spin_unlock_bh(&dev->bss_lock);
 325 }
 326
 327 void cfg80211_bss_expire(struct cfg80211_registered_device *dev)
 328 {
 329         __cfg80211_bss_expire(dev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
 330 }
 331
 332 const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len)
 333 {
 334         while (len > 2 && ies[0] != eid) {
 335                 len -= ies[1] + 2;
 336                 ies += ies[1] + 2;
 337         }
 338         if (len < 2)
 339                 return NULL;
 340         if (len < 2 + ies[1])
 341                 return NULL;
 342         return ies;
 343 }
 344 EXPORT_SYMBOL(cfg80211_find_ie);
 345
 346 const u8 *cfg80211_find_vendor_ie(unsigned int oui, u8 oui_type,
 347                                   const u8 *ies, int len)
 348 {
 349         struct ieee80211_vendor_ie *ie;
 350         const u8 *pos = ies, *end = ies + len;
 351         int ie_oui;
 352
 353         while (pos < end) {
 354                 pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos,
 355                                        end - pos);
 356                 if (!pos)
 357                         return NULL;
 358
 359                 ie = (struct ieee80211_vendor_ie *)pos;
 360
 361                 /* make sure we can access ie->len */
 362                 BUILD_BUG_ON(offsetof(struct ieee80211_vendor_ie, len) != 1);
 363
 364                 if (ie->len < sizeof(*ie))
 365                         goto cont;
 366
 367                 ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2];
 368                 if (ie_oui == oui && ie->oui_type == oui_type)
 369                         return pos;
 370 cont:
 371                 pos += 2 + ie->len;
 372         }
 373         return NULL;
 374 }
 375 EXPORT_SYMBOL(cfg80211_find_vendor_ie);
 376
 377 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
 378                    const u8 *ssid, size_t ssid_len)
 379 {
 380         const struct cfg80211_bss_ies *ies;
 381         const u8 *ssidie;
 382
 383         if (bssid && !ether_addr_equal(a->bssid, bssid))
 384                 return false;
 385
 386         if (!ssid)
 387                 return true;
 388
 389         ies = rcu_access_pointer(a->ies);
 390         if (!ies)
 391                 return false;
 392         ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
 393         if (!ssidie)
 394                 return false;
 395         if (ssidie[1] != ssid_len)
 396                 return false;
 397         return memcmp(ssidie + 2, ssid, ssid_len) == 0;
 398 }
 399
 400 /**
 401  * enum bss_compare_mode - BSS compare mode
 402  * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
 403  * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
 404  * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
 405  */
 406 enum bss_compare_mode {
 407         BSS_CMP_REGULAR,
 408         BSS_CMP_HIDE_ZLEN,
 409         BSS_CMP_HIDE_NUL,
 410 };
 411
 412 static int cmp_bss(struct cfg80211_bss *a,
 413                    struct cfg80211_bss *b,
 414                    enum bss_compare_mode mode)
 415 {
 416         const struct cfg80211_bss_ies *a_ies, *b_ies;
 417         const u8 *ie1 = NULL;
 418         const u8 *ie2 = NULL;
 419         int i, r;
 420
 421         if (a->channel != b->channel)
 422                 return b->channel->center_freq - a->channel->center_freq;
 423
 424         a_ies = rcu_access_pointer(a->ies);
 425         if (!a_ies)
 426                 return -1;
 427         b_ies = rcu_access_pointer(b->ies);
 428         if (!b_ies)
 429                 return 1;
 430
 431         if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
 432                 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
 433                                        a_ies->data, a_ies->len);
 434         if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
 435                 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
 436                                        b_ies->data, b_ies->len);
 437         if (ie1 && ie2) {
 438                 int mesh_id_cmp;
 439
 440                 if (ie1[1] == ie2[1])
 441                         mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
 442                 else
 443                         mesh_id_cmp = ie2[1] - ie1[1];
 444
 445                 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
 446                                        a_ies->data, a_ies->len);
 447                 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
 448                                        b_ies->data, b_ies->len);
 449                 if (ie1 && ie2) {
 450                         if (mesh_id_cmp)
 451                                 return mesh_id_cmp;
 452                         if (ie1[1] != ie2[1])
 453                                 return ie2[1] - ie1[1];
 454                         return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
 455                 }
 456         }
 457
 458         r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
 459         if (r)
 460                 return r;
 461
 462         ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
 463         ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
 464
 465         if (!ie1 && !ie2)
 466                 return 0;
 467
 468         /*
 469          * Note that with "hide_ssid", the function returns a match if
 470          * the already-present BSS ("b") is a hidden SSID beacon for
 471          * the new BSS ("a").
 472          */
 473
 474         /* sort missing IE before (left of) present IE */
 475         if (!ie1)
 476                 return -1;
 477         if (!ie2)
 478                 return 1;
 479
 480         switch (mode) {
 481         case BSS_CMP_HIDE_ZLEN:
 482                 /*
 483                  * In ZLEN mode we assume the BSS entry we're
 484                  * looking for has a zero-length SSID. So if
 485                  * the one we're looking at right now has that,
 486                  * return 0. Otherwise, return the difference
 487                  * in length, but since we're looking for the
 488                  * 0-length it's really equivalent to returning
 489                  * the length of the one we're looking at.
 490                  *
 491                  * No content comparison is needed as we assume
 492                  * the content length is zero.
 493                  */
 494                 return ie2[1];
 495         case BSS_CMP_REGULAR:
 496         default:
 497                 /* sort by length first, then by contents */
 498                 if (ie1[1] != ie2[1])
 499                         return ie2[1] - ie1[1];
 500                 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
 501         case BSS_CMP_HIDE_NUL:
 502                 if (ie1[1] != ie2[1])
 503                         return ie2[1] - ie1[1];
 504                 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
 505                 for (i = 0; i < ie2[1]; i++)
 506                         if (ie2[i + 2])
 507                                 return -1;
 508                 return 0;
 509         }
 510 }
 511
 512 /* Returned bss is reference counted and must be cleaned up appropriately. */
 513 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
 514                                       struct ieee80211_channel *channel,
 515                                       const u8 *bssid,
 516                                       const u8 *ssid, size_t ssid_len,
 517                                       u16 capa_mask, u16 capa_val)
 518 {
 519         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 520         struct cfg80211_internal_bss *bss, *res = NULL;
 521         unsigned long now = jiffies;
 522
 523         trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, capa_mask,
 524                                capa_val);
 525
 526         spin_lock_bh(&dev->bss_lock);
 527
 528         list_for_each_entry(bss, &dev->bss_list, list) {
 529                 if ((bss->pub.capability & capa_mask) != capa_val)
 530                         continue;
 531                 if (channel && bss->pub.channel != channel)
 532                         continue;
 533                 /* Don't get expired BSS structs */
 534                 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
 535                     !atomic_read(&bss->hold))
 536                         continue;
 537                 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
 538                         res = bss;
 539                         bss_ref_get(dev, res);
 540                         break;
 541                 }
 542         }
 543
 544         spin_unlock_bh(&dev->bss_lock);
 545         if (!res)
 546                 return NULL;
 547         trace_cfg80211_return_bss(&res->pub);
 548         return &res->pub;
 549 }
 550 EXPORT_SYMBOL(cfg80211_get_bss);
 551
 552 static void rb_insert_bss(struct cfg80211_registered_device *dev,
 553                           struct cfg80211_internal_bss *bss)
 554 {
 555         struct rb_node **p = &dev->bss_tree.rb_node;
 556         struct rb_node *parent = NULL;
 557         struct cfg80211_internal_bss *tbss;
 558         int cmp;
 559
 560         while (*p) {
 561                 parent = *p;
 562                 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
 563
 564                 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
 565
 566                 if (WARN_ON(!cmp)) {
 567                         /* will sort of leak this BSS */
 568                         return;
 569                 }
 570
 571                 if (cmp < 0)
 572                         p = &(*p)->rb_left;
 573                 else
 574                         p = &(*p)->rb_right;
 575         }
 576
 577         rb_link_node(&bss->rbn, parent, p);
 578         rb_insert_color(&bss->rbn, &dev->bss_tree);
 579 }
 580
 581 static struct cfg80211_internal_bss *
 582 rb_find_bss(struct cfg80211_registered_device *dev,
 583             struct cfg80211_internal_bss *res,
 584             enum bss_compare_mode mode)
 585 {
 586         struct rb_node *n = dev->bss_tree.rb_node;
 587         struct cfg80211_internal_bss *bss;
 588         int r;
 589
 590         while (n) {
 591                 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
 592                 r = cmp_bss(&res->pub, &bss->pub, mode);
 593
 594                 if (r == 0)
 595                         return bss;
 596                 else if (r < 0)
 597                         n = n->rb_left;
 598                 else
 599                         n = n->rb_right;
 600         }
 601
 602         return NULL;
 603 }
 604
 605 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *dev,
 606                                    struct cfg80211_internal_bss *new)
 607 {
 608         const struct cfg80211_bss_ies *ies;
 609         struct cfg80211_internal_bss *bss;
 610         const u8 *ie;
 611         int i, ssidlen;
 612         u8 fold = 0;
 613
 614         ies = rcu_access_pointer(new->pub.beacon_ies);
 615         if (WARN_ON(!ies))
 616                 return false;
 617
 618         ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
 619         if (!ie) {
 620                 /* nothing to do */
 621                 return true;
 622         }
 623
 624         ssidlen = ie[1];
 625         for (i = 0; i < ssidlen; i++)
 626                 fold |= ie[2 + i];
 627
 628         if (fold) {
 629                 /* not a hidden SSID */
 630                 return true;
 631         }
 632
 633         /* This is the bad part ... */
 634
 635         list_for_each_entry(bss, &dev->bss_list, list) {
 636                 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
 637                         continue;
 638                 if (bss->pub.channel != new->pub.channel)
 639                         continue;
 640                 if (bss->pub.scan_width != new->pub.scan_width)
 641                         continue;
 642                 if (rcu_access_pointer(bss->pub.beacon_ies))
 643                         continue;
 644                 ies = rcu_access_pointer(bss->pub.ies);
 645                 if (!ies)
 646                         continue;
 647                 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
 648                 if (!ie)
 649                         continue;
 650                 if (ssidlen && ie[1] != ssidlen)
 651                         continue;
 652                 /* that would be odd ... */
 653                 if (bss->pub.beacon_ies)
 654                         continue;
 655                 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
 656                         continue;
 657                 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
 658                         list_del(&bss->hidden_list);
 659                 /* combine them */
 660                 list_add(&bss->hidden_list, &new->hidden_list);
 661                 bss->pub.hidden_beacon_bss = &new->pub;
 662                 new->refcount += bss->refcount;
 663                 rcu_assign_pointer(bss->pub.beacon_ies,
 664                                    new->pub.beacon_ies);
 665         }
 666
 667         return true;
 668 }
 669
 670 /* Returned bss is reference counted and must be cleaned up appropriately. */
 671 static struct cfg80211_internal_bss *
 672 cfg80211_bss_update(struct cfg80211_registered_device *dev,
 673                     struct cfg80211_internal_bss *tmp)
 674 {
 675         struct cfg80211_internal_bss *found = NULL;
 676
 677         if (WARN_ON(!tmp->pub.channel))
 678                 return NULL;
 679
 680         tmp->ts = jiffies;
 681
 682         spin_lock_bh(&dev->bss_lock);
 683
 684         if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
 685                 spin_unlock_bh(&dev->bss_lock);
 686                 return NULL;
 687         }
 688
 689         found = rb_find_bss(dev, tmp, BSS_CMP_REGULAR);
 690
 691         if (found) {
 692                 /* Update IEs */
 693                 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
 694                         const struct cfg80211_bss_ies *old;
 695
 696                         old = rcu_access_pointer(found->pub.proberesp_ies);
 697
 698                         rcu_assign_pointer(found->pub.proberesp_ies,
 699                                            tmp->pub.proberesp_ies);
 700                         /* Override possible earlier Beacon frame IEs */
 701                         rcu_assign_pointer(found->pub.ies,
 702                                            tmp->pub.proberesp_ies);
 703                         if (old)
 704                                 kfree_rcu((struct cfg80211_bss_ies *)old,
 705                                           rcu_head);
 706                 } else if (rcu_access_pointer(tmp->pub.beacon_ies)) {
 707                         const struct cfg80211_bss_ies *old;
 708                         struct cfg80211_internal_bss *bss;
 709
 710                         if (found->pub.hidden_beacon_bss &&
 711                             !list_empty(&found->hidden_list)) {
 712                                 const struct cfg80211_bss_ies *f;
 713
 714                                 /*
 715                                  * The found BSS struct is one of the probe
 716                                  * response members of a group, but we're
 717                                  * receiving a beacon (beacon_ies in the tmp
 718                                  * bss is used). This can only mean that the
 719                                  * AP changed its beacon from not having an
 720                                  * SSID to showing it, which is confusing so
 721                                  * drop this information.
 722                                  */
 723
 724                                 f = rcu_access_pointer(tmp->pub.beacon_ies);
 725                                 kfree_rcu((struct cfg80211_bss_ies *)f,
 726                                           rcu_head);
 727                                 goto drop;
 728                         }
 729
 730                         old = rcu_access_pointer(found->pub.beacon_ies);
 731
 732                         rcu_assign_pointer(found->pub.beacon_ies,
 733                                            tmp->pub.beacon_ies);
 734
 735                         /* Override IEs if they were from a beacon before */
 736                         if (old == rcu_access_pointer(found->pub.ies))
 737                                 rcu_assign_pointer(found->pub.ies,
 738                                                    tmp->pub.beacon_ies);
 739
 740                         /* Assign beacon IEs to all sub entries */
 741                         list_for_each_entry(bss, &found->hidden_list,
 742                                             hidden_list) {
 743                                 const struct cfg80211_bss_ies *ies;
 744
 745                                 ies = rcu_access_pointer(bss->pub.beacon_ies);
 746                                 WARN_ON(ies != old);
 747
 748                                 rcu_assign_pointer(bss->pub.beacon_ies,
 749                                                    tmp->pub.beacon_ies);
 750                         }
 751
 752                         if (old)
 753                                 kfree_rcu((struct cfg80211_bss_ies *)old,
 754                                           rcu_head);
 755                 }
 756
 757                 found->pub.beacon_interval = tmp->pub.beacon_interval;
 758                 found->pub.signal = tmp->pub.signal;
 759                 found->pub.capability = tmp->pub.capability;
 760                 found->ts = tmp->ts;
 761         } else {
 762                 struct cfg80211_internal_bss *new;
 763                 struct cfg80211_internal_bss *hidden;
 764                 struct cfg80211_bss_ies *ies;
 765
 766                 /*
 767                  * create a copy -- the "res" variable that is passed in
 768                  * is allocated on the stack since it's not needed in the
 769                  * more common case of an update
 770                  */
 771                 new = kzalloc(sizeof(*new) + dev->wiphy.bss_priv_size,
 772                               GFP_ATOMIC);
 773                 if (!new) {
 774                         ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
 775                         if (ies)
 776                                 kfree_rcu(ies, rcu_head);
 777                         ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
 778                         if (ies)
 779                                 kfree_rcu(ies, rcu_head);
 780                         goto drop;
 781                 }
 782                 memcpy(new, tmp, sizeof(*new));
 783                 new->refcount = 1;
 784                 INIT_LIST_HEAD(&new->hidden_list);
 785
 786                 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
 787                         hidden = rb_find_bss(dev, tmp, BSS_CMP_HIDE_ZLEN);
 788                         if (!hidden)
 789                                 hidden = rb_find_bss(dev, tmp,
 790                                                      BSS_CMP_HIDE_NUL);
 791                         if (hidden) {
 792                                 new->pub.hidden_beacon_bss = &hidden->pub;
 793                                 list_add(&new->hidden_list,
 794                                          &hidden->hidden_list);
 795                                 hidden->refcount++;
 796                                 rcu_assign_pointer(new->pub.beacon_ies,
 797                                                    hidden->pub.beacon_ies);
 798                         }
 799                 } else {
 800                         /*
 801                          * Ok so we found a beacon, and don't have an entry. If
 802                          * it's a beacon with hidden SSID, we might be in for an
 803                          * expensive search for any probe responses that should
 804                          * be grouped with this beacon for updates ...
 805                          */
 806                         if (!cfg80211_combine_bsses(dev, new)) {
 807                                 kfree(new);
 808                                 goto drop;
 809                         }
 810                 }
 811
 812                 list_add_tail(&new->list, &dev->bss_list);
 813                 rb_insert_bss(dev, new);
 814                 found = new;
 815         }
 816
 817         dev->bss_generation++;
 818         bss_ref_get(dev, found);
 819         spin_unlock_bh(&dev->bss_lock);
 820
 821         return found;
 822  drop:
 823         spin_unlock_bh(&dev->bss_lock);
 824         return NULL;
 825 }
 826
 827 static struct ieee80211_channel *
 828 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
 829                          struct ieee80211_channel *channel)
 830 {
 831         const u8 *tmp;
 832         u32 freq;
 833         int channel_number = -1;
 834
 835         tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen);
 836         if (tmp && tmp[1] == 1) {
 837                 channel_number = tmp[2];
 838         } else {
 839                 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen);
 840                 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) {
 841                         struct ieee80211_ht_operation *htop = (void *)(tmp + 2);
 842
 843                         channel_number = htop->primary_chan;
 844                 }
 845         }
 846
 847         if (channel_number < 0)
 848                 return channel;
 849
 850         freq = ieee80211_channel_to_frequency(channel_number, channel->band);
 851         channel = ieee80211_get_channel(wiphy, freq);
 852         if (!channel)
 853                 return NULL;
 854         if (channel->flags & IEEE80211_CHAN_DISABLED)
 855                 return NULL;
 856         return channel;
 857 }
 858
 859 /* Returned bss is reference counted and must be cleaned up appropriately. */
 860 struct cfg80211_bss*
 861 cfg80211_inform_bss_width(struct wiphy *wiphy,
 862                           struct ieee80211_channel *channel,
 863                           enum nl80211_bss_scan_width scan_width,
 864                           const u8 *bssid, u64 tsf, u16 capability,
 865                           u16 beacon_interval, const u8 *ie, size_t ielen,
 866                           s32 signal, gfp_t gfp)
 867 {
 868         struct cfg80211_bss_ies *ies;
 869         struct cfg80211_internal_bss tmp = {}, *res;
 870
 871         if (WARN_ON(!wiphy))
 872                 return NULL;
 873
 874         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
 875                         (signal < 0 || signal > 100)))
 876                 return NULL;
 877
 878         channel = cfg80211_get_bss_channel(wiphy, ie, ielen, channel);
 879         if (!channel)
 880                 return NULL;
 881
 882         memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
 883         tmp.pub.channel = channel;
 884         tmp.pub.scan_width = scan_width;
 885         tmp.pub.signal = signal;
 886         tmp.pub.beacon_interval = beacon_interval;
 887         tmp.pub.capability = capability;
 888         /*
 889          * Since we do not know here whether the IEs are from a Beacon or Probe
 890          * Response frame, we need to pick one of the options and only use it
 891          * with the driver that does not provide the full Beacon/Probe Response
 892          * frame. Use Beacon frame pointer to avoid indicating that this should
 893          * override the IEs pointer should we have received an earlier
 894          * indication of Probe Response data.
 895          */
 896         ies = kmalloc(sizeof(*ies) + ielen, gfp);
 897         if (!ies)
 898                 return NULL;
 899         ies->len = ielen;
 900         ies->tsf = tsf;
 901         memcpy(ies->data, ie, ielen);
 902
 903         rcu_assign_pointer(tmp.pub.beacon_ies, ies);
 904         rcu_assign_pointer(tmp.pub.ies, ies);
 905
 906         res = cfg80211_bss_update(wiphy_to_dev(wiphy), &tmp);
 907         if (!res)
 908                 return NULL;
 909
 910         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 911                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 912
 913         trace_cfg80211_return_bss(&res->pub);
 914         /* cfg80211_bss_update gives us a referenced result */
 915         return &res->pub;
 916 }
 917 EXPORT_SYMBOL(cfg80211_inform_bss_width);
 918
 919 /* Returned bss is reference counted and must be cleaned up appropriately. */
 920 struct cfg80211_bss *
 921 cfg80211_inform_bss_width_frame(struct wiphy *wiphy,
 922                                 struct ieee80211_channel *channel,
 923                                 enum nl80211_bss_scan_width scan_width,
 924                                 struct ieee80211_mgmt *mgmt, size_t len,
 925                                 s32 signal, gfp_t gfp)
 926 {
 927         struct cfg80211_internal_bss tmp = {}, *res;
 928         struct cfg80211_bss_ies *ies;
 929         size_t ielen = len - offsetof(struct ieee80211_mgmt,
 930                                       u.probe_resp.variable);
 931
 932         BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
 933                         offsetof(struct ieee80211_mgmt, u.beacon.variable));
 934
 935         trace_cfg80211_inform_bss_width_frame(wiphy, channel, scan_width, mgmt,
 936                                               len, signal);
 937
 938         if (WARN_ON(!mgmt))
 939                 return NULL;
 940
 941         if (WARN_ON(!wiphy))
 942                 return NULL;
 943
 944         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
 945                     (signal < 0 || signal > 100)))
 946                 return NULL;
 947
 948         if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
 949                 return NULL;
 950
 951         channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable,
 952                                            ielen, channel);
 953         if (!channel)
 954                 return NULL;
 955
 956         ies = kmalloc(sizeof(*ies) + ielen, gfp);
 957         if (!ies)
 958                 return NULL;
 959         ies->len = ielen;
 960         ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
 961         memcpy(ies->data, mgmt->u.probe_resp.variable, ielen);
 962
 963         if (ieee80211_is_probe_resp(mgmt->frame_control))
 964                 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
 965         else
 966                 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
 967         rcu_assign_pointer(tmp.pub.ies, ies);
 968
 969         memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN);
 970         tmp.pub.channel = channel;
 971         tmp.pub.scan_width = scan_width;
 972         tmp.pub.signal = signal;
 973         tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
 974         tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
 975
 976         res = cfg80211_bss_update(wiphy_to_dev(wiphy), &tmp);
 977         if (!res)
 978                 return NULL;
 979
 980         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 981                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 982
 983         trace_cfg80211_return_bss(&res->pub);
 984         /* cfg80211_bss_update gives us a referenced result */
 985         return &res->pub;
 986 }
 987 EXPORT_SYMBOL(cfg80211_inform_bss_width_frame);
 988
 989 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
 990 {
 991         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 992         struct cfg80211_internal_bss *bss;
 993
 994         if (!pub)
 995                 return;
 996
 997         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 998
 999         spin_lock_bh(&dev->bss_lock);
1000         bss_ref_get(dev, bss);
1001         spin_unlock_bh(&dev->bss_lock);
1002 }
1003 EXPORT_SYMBOL(cfg80211_ref_bss);
1004
1005 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1006 {
1007         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
1008         struct cfg80211_internal_bss *bss;
1009
1010         if (!pub)
1011                 return;
1012
1013         bss = container_of(pub, struct cfg80211_internal_bss, pub);
1014
1015         spin_lock_bh(&dev->bss_lock);
1016         bss_ref_put(dev, bss);
1017         spin_unlock_bh(&dev->bss_lock);
1018 }
1019 EXPORT_SYMBOL(cfg80211_put_bss);
1020
1021 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1022 {
1023         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
1024         struct cfg80211_internal_bss *bss;
1025
1026         if (WARN_ON(!pub))
1027                 return;
1028
1029         bss = container_of(pub, struct cfg80211_internal_bss, pub);
1030
1031         spin_lock_bh(&dev->bss_lock);
1032         if (!list_empty(&bss->list)) {
1033                 if (__cfg80211_unlink_bss(dev, bss))
1034                         dev->bss_generation++;
1035         }
1036         spin_unlock_bh(&dev->bss_lock);
1037 }
1038 EXPORT_SYMBOL(cfg80211_unlink_bss);
1039
1040 #ifdef CONFIG_CFG80211_WEXT
1041 static struct cfg80211_registered_device *
1042 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
1043 {
1044         struct cfg80211_registered_device *rdev;
1045         struct net_device *dev;
1046
1047         ASSERT_RTNL();
1048
1049         dev = dev_get_by_index(net, ifindex);
1050         if (!dev)
1051                 return ERR_PTR(-ENODEV);
1052         if (dev->ieee80211_ptr)
1053                 rdev = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
1054         else
1055                 rdev = ERR_PTR(-ENODEV);
1056         dev_put(dev);
1057         return rdev;
1058 }
1059
1060 int cfg80211_wext_siwscan(struct net_device *dev,
1061                           struct iw_request_info *info,
1062                           union iwreq_data *wrqu, char *extra)
1063 {
1064         struct cfg80211_registered_device *rdev;
1065         struct wiphy *wiphy;
1066         struct iw_scan_req *wreq = NULL;
1067         struct cfg80211_scan_request *creq = NULL;
1068         int i, err, n_channels = 0;
1069         enum ieee80211_band band;
1070
1071         if (!netif_running(dev))
1072                 return -ENETDOWN;
1073
1074         if (wrqu->data.length == sizeof(struct iw_scan_req))
1075                 wreq = (struct iw_scan_req *)extra;
1076
1077         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1078
1079         if (IS_ERR(rdev))
1080                 return PTR_ERR(rdev);
1081
1082         if (rdev->scan_req) {
1083                 err = -EBUSY;
1084                 goto out;
1085         }
1086
1087         wiphy = &rdev->wiphy;
1088
1089         /* Determine number of channels, needed to allocate creq */
1090         if (wreq && wreq->num_channels)
1091                 n_channels = wreq->num_channels;
1092         else
1093                 n_channels = ieee80211_get_num_supported_channels(wiphy);
1094
1095         creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
1096                        n_channels * sizeof(void *),
1097                        GFP_ATOMIC);
1098         if (!creq) {
1099                 err = -ENOMEM;
1100                 goto out;
1101         }
1102
1103         creq->wiphy = wiphy;
1104         creq->wdev = dev->ieee80211_ptr;
1105         /* SSIDs come after channels */
1106         creq->ssids = (void *)&creq->channels[n_channels];
1107         creq->n_channels = n_channels;
1108         creq->n_ssids = 1;
1109         creq->scan_start = jiffies;
1110
1111         /* translate "Scan on frequencies" request */
1112         i = 0;
1113         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1114                 int j;
1115
1116                 if (!wiphy->bands[band])
1117                         continue;
1118
1119                 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
1120                         /* ignore disabled channels */
1121                         if (wiphy->bands[band]->channels[j].flags &
1122                                                 IEEE80211_CHAN_DISABLED)
1123                                 continue;
1124
1125                         /* If we have a wireless request structure and the
1126                          * wireless request specifies frequencies, then search
1127                          * for the matching hardware channel.
1128                          */
1129                         if (wreq && wreq->num_channels) {
1130                                 int k;
1131                                 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
1132                                 for (k = 0; k < wreq->num_channels; k++) {
1133                                         int wext_freq = cfg80211_wext_freq(wiphy, &wreq->channel_list[k]);
1134                                         if (wext_freq == wiphy_freq)
1135                                                 goto wext_freq_found;
1136                                 }
1137                                 goto wext_freq_not_found;
1138                         }
1139
1140                 wext_freq_found:
1141                         creq->channels[i] = &wiphy->bands[band]->channels[j];
1142                         i++;
1143                 wext_freq_not_found: ;
1144                 }
1145         }
1146         /* No channels found? */
1147         if (!i) {
1148                 err = -EINVAL;
1149                 goto out;
1150         }
1151
1152         /* Set real number of channels specified in creq->channels[] */
1153         creq->n_channels = i;
1154
1155         /* translate "Scan for SSID" request */
1156         if (wreq) {
1157                 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
1158                         if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
1159                                 err = -EINVAL;
1160                                 goto out;
1161                         }
1162                         memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
1163                         creq->ssids[0].ssid_len = wreq->essid_len;
1164                 }
1165                 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
1166                         creq->n_ssids = 0;
1167         }
1168
1169         for (i = 0; i < IEEE80211_NUM_BANDS; i++)
1170                 if (wiphy->bands[i])
1171                         creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
1172
1173         rdev->scan_req = creq;
1174         err = rdev_scan(rdev, creq);
1175         if (err) {
1176                 rdev->scan_req = NULL;
1177                 /* creq will be freed below */
1178         } else {
1179                 nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
1180                 /* creq now owned by driver */
1181                 creq = NULL;
1182                 dev_hold(dev);
1183         }
1184  out:
1185         kfree(creq);
1186         return err;
1187 }
1188 EXPORT_SYMBOL_GPL(cfg80211_wext_siwscan);
1189
1190 static void ieee80211_scan_add_ies(struct iw_request_info *info,
1191                                    const struct cfg80211_bss_ies *ies,
1192                                    char **current_ev, char *end_buf)
1193 {
1194         const u8 *pos, *end, *next;
1195         struct iw_event iwe;
1196
1197         if (!ies)
1198                 return;
1199
1200         /*
1201          * If needed, fragment the IEs buffer (at IE boundaries) into short
1202          * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
1203          */
1204         pos = ies->data;
1205         end = pos + ies->len;
1206
1207         while (end - pos > IW_GENERIC_IE_MAX) {
1208                 next = pos + 2 + pos[1];
1209                 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
1210                         next = next + 2 + next[1];
1211
1212                 memset(&iwe, 0, sizeof(iwe));
1213                 iwe.cmd = IWEVGENIE;
1214                 iwe.u.data.length = next - pos;
1215                 *current_ev = iwe_stream_add_point(info, *current_ev,
1216                                                    end_buf, &iwe,
1217                                                    (void *)pos);
1218
1219                 pos = next;
1220         }
1221
1222         if (end > pos) {
1223                 memset(&iwe, 0, sizeof(iwe));
1224                 iwe.cmd = IWEVGENIE;
1225                 iwe.u.data.length = end - pos;
1226                 *current_ev = iwe_stream_add_point(info, *current_ev,
1227                                                    end_buf, &iwe,
1228                                                    (void *)pos);
1229         }
1230 }
1231
1232 static char *
1233 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
1234               struct cfg80211_internal_bss *bss, char *current_ev,
1235               char *end_buf)
1236 {
1237         const struct cfg80211_bss_ies *ies;
1238         struct iw_event iwe;
1239         const u8 *ie;
1240         u8 *buf, *cfg, *p;
1241         int rem, i, sig;
1242         bool ismesh = false;
1243
1244         memset(&iwe, 0, sizeof(iwe));
1245         iwe.cmd = SIOCGIWAP;
1246         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
1247         memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
1248         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1249                                           IW_EV_ADDR_LEN);
1250
1251         memset(&iwe, 0, sizeof(iwe));
1252         iwe.cmd = SIOCGIWFREQ;
1253         iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
1254         iwe.u.freq.e = 0;
1255         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1256                                           IW_EV_FREQ_LEN);
1257
1258         memset(&iwe, 0, sizeof(iwe));
1259         iwe.cmd = SIOCGIWFREQ;
1260         iwe.u.freq.m = bss->pub.channel->center_freq;
1261         iwe.u.freq.e = 6;
1262         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1263                                           IW_EV_FREQ_LEN);
1264
1265         if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
1266                 memset(&iwe, 0, sizeof(iwe));
1267                 iwe.cmd = IWEVQUAL;
1268                 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
1269                                      IW_QUAL_NOISE_INVALID |
1270                                      IW_QUAL_QUAL_UPDATED;
1271                 switch (wiphy->signal_type) {
1272                 case CFG80211_SIGNAL_TYPE_MBM:
1273                         sig = bss->pub.signal / 100;
1274                         iwe.u.qual.level = sig;
1275                         iwe.u.qual.updated |= IW_QUAL_DBM;
1276                         if (sig < -110)         /* rather bad */
1277                                 sig = -110;
1278                         else if (sig > -40)     /* perfect */
1279                                 sig = -40;
1280                         /* will give a range of 0 .. 70 */
1281                         iwe.u.qual.qual = sig + 110;
1282                         break;
1283                 case CFG80211_SIGNAL_TYPE_UNSPEC:
1284                         iwe.u.qual.level = bss->pub.signal;
1285                         /* will give range 0 .. 100 */
1286                         iwe.u.qual.qual = bss->pub.signal;
1287                         break;
1288                 default:
1289                         /* not reached */
1290                         break;
1291                 }
1292                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1293                                                   &iwe, IW_EV_QUAL_LEN);
1294         }
1295
1296         memset(&iwe, 0, sizeof(iwe));
1297         iwe.cmd = SIOCGIWENCODE;
1298         if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
1299                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
1300         else
1301                 iwe.u.data.flags = IW_ENCODE_DISABLED;
1302         iwe.u.data.length = 0;
1303         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1304                                           &iwe, "");
1305
1306         rcu_read_lock();
1307         ies = rcu_dereference(bss->pub.ies);
1308         rem = ies->len;
1309         ie = ies->data;
1310
1311         while (rem >= 2) {
1312                 /* invalid data */
1313                 if (ie[1] > rem - 2)
1314                         break;
1315
1316                 switch (ie[0]) {
1317                 case WLAN_EID_SSID:
1318                         memset(&iwe, 0, sizeof(iwe));
1319                         iwe.cmd = SIOCGIWESSID;
1320                         iwe.u.data.length = ie[1];
1321                         iwe.u.data.flags = 1;
1322                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1323                                                           &iwe, (u8 *)ie + 2);
1324                         break;
1325                 case WLAN_EID_MESH_ID:
1326                         memset(&iwe, 0, sizeof(iwe));
1327                         iwe.cmd = SIOCGIWESSID;
1328                         iwe.u.data.length = ie[1];
1329                         iwe.u.data.flags = 1;
1330                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1331                                                           &iwe, (u8 *)ie + 2);
1332                         break;
1333                 case WLAN_EID_MESH_CONFIG:
1334                         ismesh = true;
1335                         if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
1336                                 break;
1337                         buf = kmalloc(50, GFP_ATOMIC);
1338                         if (!buf)
1339                                 break;
1340                         cfg = (u8 *)ie + 2;
1341                         memset(&iwe, 0, sizeof(iwe));
1342                         iwe.cmd = IWEVCUSTOM;
1343                         sprintf(buf, "Mesh Network Path Selection Protocol ID: "
1344                                 "0x%02X", cfg[0]);
1345                         iwe.u.data.length = strlen(buf);
1346                         current_ev = iwe_stream_add_point(info, current_ev,
1347                                                           end_buf,
1348                                                           &iwe, buf);
1349                         sprintf(buf, "Path Selection Metric ID: 0x%02X",
1350                                 cfg[1]);
1351                         iwe.u.data.length = strlen(buf);
1352                         current_ev = iwe_stream_add_point(info, current_ev,
1353                                                           end_buf,
1354                                                           &iwe, buf);
1355                         sprintf(buf, "Congestion Control Mode ID: 0x%02X",
1356                                 cfg[2]);
1357                         iwe.u.data.length = strlen(buf);
1358                         current_ev = iwe_stream_add_point(info, current_ev,
1359                                                           end_buf,
1360                                                           &iwe, buf);
1361                         sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
1362                         iwe.u.data.length = strlen(buf);
1363                         current_ev = iwe_stream_add_point(info, current_ev,
1364                                                           end_buf,
1365                                                           &iwe, buf);
1366                         sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
1367                         iwe.u.data.length = strlen(buf);
1368                         current_ev = iwe_stream_add_point(info, current_ev,
1369                                                           end_buf,
1370                                                           &iwe, buf);
1371                         sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
1372                         iwe.u.data.length = strlen(buf);
1373                         current_ev = iwe_stream_add_point(info, current_ev,
1374                                                           end_buf,
1375                                                           &iwe, buf);
1376                         sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
1377                         iwe.u.data.length = strlen(buf);
1378                         current_ev = iwe_stream_add_point(info, current_ev,
1379                                                           end_buf,
1380                                                           &iwe, buf);
1381                         kfree(buf);
1382                         break;
1383                 case WLAN_EID_SUPP_RATES:
1384                 case WLAN_EID_EXT_SUPP_RATES:
1385                         /* display all supported rates in readable format */
1386                         p = current_ev + iwe_stream_lcp_len(info);
1387
1388                         memset(&iwe, 0, sizeof(iwe));
1389                         iwe.cmd = SIOCGIWRATE;
1390                         /* Those two flags are ignored... */
1391                         iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
1392
1393                         for (i = 0; i < ie[1]; i++) {
1394                                 iwe.u.bitrate.value =
1395                                         ((ie[i + 2] & 0x7f) * 500000);
1396                                 p = iwe_stream_add_value(info, current_ev, p,
1397                                                 end_buf, &iwe, IW_EV_PARAM_LEN);
1398                         }
1399                         current_ev = p;
1400                         break;
1401                 }
1402                 rem -= ie[1] + 2;
1403                 ie += ie[1] + 2;
1404         }
1405
1406         if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
1407             ismesh) {
1408                 memset(&iwe, 0, sizeof(iwe));
1409                 iwe.cmd = SIOCGIWMODE;
1410                 if (ismesh)
1411                         iwe.u.mode = IW_MODE_MESH;
1412                 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
1413                         iwe.u.mode = IW_MODE_MASTER;
1414                 else
1415                         iwe.u.mode = IW_MODE_ADHOC;
1416                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1417                                                   &iwe, IW_EV_UINT_LEN);
1418         }
1419
1420         buf = kmalloc(31, GFP_ATOMIC);
1421         if (buf) {
1422                 memset(&iwe, 0, sizeof(iwe));
1423                 iwe.cmd = IWEVCUSTOM;
1424                 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
1425                 iwe.u.data.length = strlen(buf);
1426                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1427                                                   &iwe, buf);
1428                 memset(&iwe, 0, sizeof(iwe));
1429                 iwe.cmd = IWEVCUSTOM;
1430                 sprintf(buf, " Last beacon: %ums ago",
1431                         elapsed_jiffies_msecs(bss->ts));
1432                 iwe.u.data.length = strlen(buf);
1433                 current_ev = iwe_stream_add_point(info, current_ev,
1434                                                   end_buf, &iwe, buf);
1435                 kfree(buf);
1436         }
1437
1438         ieee80211_scan_add_ies(info, ies, &current_ev, end_buf);
1439         rcu_read_unlock();
1440
1441         return current_ev;
1442 }
1443
1444
1445 static int ieee80211_scan_results(struct cfg80211_registered_device *dev,
1446                                   struct iw_request_info *info,
1447                                   char *buf, size_t len)
1448 {
1449         char *current_ev = buf;
1450         char *end_buf = buf + len;
1451         struct cfg80211_internal_bss *bss;
1452
1453         spin_lock_bh(&dev->bss_lock);
1454         cfg80211_bss_expire(dev);
1455
1456         list_for_each_entry(bss, &dev->bss_list, list) {
1457                 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
1458                         spin_unlock_bh(&dev->bss_lock);
1459                         return -E2BIG;
1460                 }
1461                 current_ev = ieee80211_bss(&dev->wiphy, info, bss,
1462                                            current_ev, end_buf);
1463         }
1464         spin_unlock_bh(&dev->bss_lock);
1465         return current_ev - buf;
1466 }
1467
1468
1469 int cfg80211_wext_giwscan(struct net_device *dev,
1470                           struct iw_request_info *info,
1471                           struct iw_point *data, char *extra)
1472 {
1473         struct cfg80211_registered_device *rdev;
1474         int res;
1475
1476         if (!netif_running(dev))
1477                 return -ENETDOWN;
1478
1479         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1480
1481         if (IS_ERR(rdev))
1482                 return PTR_ERR(rdev);
1483
1484         if (rdev->scan_req)
1485                 return -EAGAIN;
1486
1487         res = ieee80211_scan_results(rdev, info, extra, data->length);
1488         data->length = 0;
1489         if (res >= 0) {
1490                 data->length = res;
1491                 res = 0;
1492         }
1493
1494         return res;
1495 }
1496 EXPORT_SYMBOL_GPL(cfg80211_wext_giwscan);
1497 #endif