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                            bool send_message)
 166 {
 167         struct cfg80211_scan_request *request;
 168         struct wireless_dev *wdev;
 169         struct sk_buff *msg;
 170 #ifdef CONFIG_CFG80211_WEXT
 171         union iwreq_data wrqu;
 172 #endif
 173
 174         ASSERT_RTNL();
 175
 176         if (rdev->scan_msg) {
 177                 nl80211_send_scan_result(rdev, rdev->scan_msg);
 178                 rdev->scan_msg = NULL;
 179                 return;
 180         }
 181
 182         request = rdev->scan_req;
 183         if (!request)
 184                 return;
 185
 186         wdev = request->wdev;
 187
 188         /*
 189          * This must be before sending the other events!
 190          * Otherwise, wpa_supplicant gets completely confused with
 191          * wext events.
 192          */
 193         if (wdev->netdev)
 194                 cfg80211_sme_scan_done(wdev->netdev);
 195
 196         if (!request->aborted &&
 197             request->flags & NL80211_SCAN_FLAG_FLUSH) {
 198                 /* flush entries from previous scans */
 199                 spin_lock_bh(&rdev->bss_lock);
 200                 __cfg80211_bss_expire(rdev, request->scan_start);
 201                 spin_unlock_bh(&rdev->bss_lock);
 202         }
 203
 204         msg = nl80211_build_scan_msg(rdev, wdev, request->aborted);
 205
 206 #ifdef CONFIG_CFG80211_WEXT
 207         if (wdev->netdev && !request->aborted) {
 208                 memset(&wrqu, 0, sizeof(wrqu));
 209
 210                 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
 211         }
 212 #endif
 213
 214         if (wdev->netdev)
 215                 dev_put(wdev->netdev);
 216
 217         rdev->scan_req = NULL;
 218         kfree(request);
 219
 220         if (!send_message)
 221                 rdev->scan_msg = msg;
 222         else
 223                 nl80211_send_scan_result(rdev, msg);
 224 }
 225
 226 void __cfg80211_scan_done(struct work_struct *wk)
 227 {
 228         struct cfg80211_registered_device *rdev;
 229
 230         rdev = container_of(wk, struct cfg80211_registered_device,
 231                             scan_done_wk);
 232
 233         rtnl_lock();
 234         ___cfg80211_scan_done(rdev, true);
 235         rtnl_unlock();
 236 }
 237
 238 void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
 239 {
 240         trace_cfg80211_scan_done(request, aborted);
 241         WARN_ON(request != wiphy_to_dev(request->wiphy)->scan_req);
 242
 243         request->aborted = aborted;
 244         request->notified = true;
 245         queue_work(cfg80211_wq, &wiphy_to_dev(request->wiphy)->scan_done_wk);
 246 }
 247 EXPORT_SYMBOL(cfg80211_scan_done);
 248
 249 void __cfg80211_sched_scan_results(struct work_struct *wk)
 250 {
 251         struct cfg80211_registered_device *rdev;
 252         struct cfg80211_sched_scan_request *request;
 253
 254         rdev = container_of(wk, struct cfg80211_registered_device,
 255                             sched_scan_results_wk);
 256
 257         rtnl_lock();
 258
 259         request = rdev->sched_scan_req;
 260
 261         /* we don't have sched_scan_req anymore if the scan is stopping */
 262         if (request) {
 263                 if (request->flags & NL80211_SCAN_FLAG_FLUSH) {
 264                         /* flush entries from previous scans */
 265                         spin_lock_bh(&rdev->bss_lock);
 266                         __cfg80211_bss_expire(rdev, request->scan_start);
 267                         spin_unlock_bh(&rdev->bss_lock);
 268                         request->scan_start =
 269                                 jiffies + msecs_to_jiffies(request->interval);
 270                 }
 271                 nl80211_send_sched_scan_results(rdev, request->dev);
 272         }
 273
 274         rtnl_unlock();
 275 }
 276
 277 void cfg80211_sched_scan_results(struct wiphy *wiphy)
 278 {
 279         trace_cfg80211_sched_scan_results(wiphy);
 280         /* ignore if we're not scanning */
 281         if (wiphy_to_dev(wiphy)->sched_scan_req)
 282                 queue_work(cfg80211_wq,
 283                            &wiphy_to_dev(wiphy)->sched_scan_results_wk);
 284 }
 285 EXPORT_SYMBOL(cfg80211_sched_scan_results);
 286
 287 void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
 288 {
 289         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
 290
 291         trace_cfg80211_sched_scan_stopped(wiphy);
 292
 293         rtnl_lock();
 294         __cfg80211_stop_sched_scan(rdev, true);
 295         rtnl_unlock();
 296 }
 297 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
 298
 299 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
 300                                bool driver_initiated)
 301 {
 302         struct net_device *dev;
 303
 304         ASSERT_RTNL();
 305
 306         if (!rdev->sched_scan_req)
 307                 return -ENOENT;
 308
 309         dev = rdev->sched_scan_req->dev;
 310
 311         if (!driver_initiated) {
 312                 int err = rdev_sched_scan_stop(rdev, dev);
 313                 if (err)
 314                         return err;
 315         }
 316
 317         nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED);
 318
 319         kfree(rdev->sched_scan_req);
 320         rdev->sched_scan_req = NULL;
 321
 322         return 0;
 323 }
 324
 325 void cfg80211_bss_age(struct cfg80211_registered_device *dev,
 326                       unsigned long age_secs)
 327 {
 328         struct cfg80211_internal_bss *bss;
 329         unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
 330
 331         spin_lock_bh(&dev->bss_lock);
 332         list_for_each_entry(bss, &dev->bss_list, list)
 333                 bss->ts -= age_jiffies;
 334         spin_unlock_bh(&dev->bss_lock);
 335 }
 336
 337 void cfg80211_bss_expire(struct cfg80211_registered_device *dev)
 338 {
 339         __cfg80211_bss_expire(dev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
 340 }
 341
 342 const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len)
 343 {
 344         while (len > 2 && ies[0] != eid) {
 345                 len -= ies[1] + 2;
 346                 ies += ies[1] + 2;
 347         }
 348         if (len < 2)
 349                 return NULL;
 350         if (len < 2 + ies[1])
 351                 return NULL;
 352         return ies;
 353 }
 354 EXPORT_SYMBOL(cfg80211_find_ie);
 355
 356 const u8 *cfg80211_find_vendor_ie(unsigned int oui, u8 oui_type,
 357                                   const u8 *ies, int len)
 358 {
 359         struct ieee80211_vendor_ie *ie;
 360         const u8 *pos = ies, *end = ies + len;
 361         int ie_oui;
 362
 363         while (pos < end) {
 364                 pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos,
 365                                        end - pos);
 366                 if (!pos)
 367                         return NULL;
 368
 369                 ie = (struct ieee80211_vendor_ie *)pos;
 370
 371                 /* make sure we can access ie->len */
 372                 BUILD_BUG_ON(offsetof(struct ieee80211_vendor_ie, len) != 1);
 373
 374                 if (ie->len < sizeof(*ie))
 375                         goto cont;
 376
 377                 ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2];
 378                 if (ie_oui == oui && ie->oui_type == oui_type)
 379                         return pos;
 380 cont:
 381                 pos += 2 + ie->len;
 382         }
 383         return NULL;
 384 }
 385 EXPORT_SYMBOL(cfg80211_find_vendor_ie);
 386
 387 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
 388                    const u8 *ssid, size_t ssid_len)
 389 {
 390         const struct cfg80211_bss_ies *ies;
 391         const u8 *ssidie;
 392
 393         if (bssid && !ether_addr_equal(a->bssid, bssid))
 394                 return false;
 395
 396         if (!ssid)
 397                 return true;
 398
 399         ies = rcu_access_pointer(a->ies);
 400         if (!ies)
 401                 return false;
 402         ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
 403         if (!ssidie)
 404                 return false;
 405         if (ssidie[1] != ssid_len)
 406                 return false;
 407         return memcmp(ssidie + 2, ssid, ssid_len) == 0;
 408 }
 409
 410 /**
 411  * enum bss_compare_mode - BSS compare mode
 412  * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
 413  * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
 414  * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
 415  */
 416 enum bss_compare_mode {
 417         BSS_CMP_REGULAR,
 418         BSS_CMP_HIDE_ZLEN,
 419         BSS_CMP_HIDE_NUL,
 420 };
 421
 422 static int cmp_bss(struct cfg80211_bss *a,
 423                    struct cfg80211_bss *b,
 424                    enum bss_compare_mode mode)
 425 {
 426         const struct cfg80211_bss_ies *a_ies, *b_ies;
 427         const u8 *ie1 = NULL;
 428         const u8 *ie2 = NULL;
 429         int i, r;
 430
 431         if (a->channel != b->channel)
 432                 return b->channel->center_freq - a->channel->center_freq;
 433
 434         a_ies = rcu_access_pointer(a->ies);
 435         if (!a_ies)
 436                 return -1;
 437         b_ies = rcu_access_pointer(b->ies);
 438         if (!b_ies)
 439                 return 1;
 440
 441         if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
 442                 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
 443                                        a_ies->data, a_ies->len);
 444         if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
 445                 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
 446                                        b_ies->data, b_ies->len);
 447         if (ie1 && ie2) {
 448                 int mesh_id_cmp;
 449
 450                 if (ie1[1] == ie2[1])
 451                         mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
 452                 else
 453                         mesh_id_cmp = ie2[1] - ie1[1];
 454
 455                 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
 456                                        a_ies->data, a_ies->len);
 457                 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
 458                                        b_ies->data, b_ies->len);
 459                 if (ie1 && ie2) {
 460                         if (mesh_id_cmp)
 461                                 return mesh_id_cmp;
 462                         if (ie1[1] != ie2[1])
 463                                 return ie2[1] - ie1[1];
 464                         return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
 465                 }
 466         }
 467
 468         r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
 469         if (r)
 470                 return r;
 471
 472         ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
 473         ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
 474
 475         if (!ie1 && !ie2)
 476                 return 0;
 477
 478         /*
 479          * Note that with "hide_ssid", the function returns a match if
 480          * the already-present BSS ("b") is a hidden SSID beacon for
 481          * the new BSS ("a").
 482          */
 483
 484         /* sort missing IE before (left of) present IE */
 485         if (!ie1)
 486                 return -1;
 487         if (!ie2)
 488                 return 1;
 489
 490         switch (mode) {
 491         case BSS_CMP_HIDE_ZLEN:
 492                 /*
 493                  * In ZLEN mode we assume the BSS entry we're
 494                  * looking for has a zero-length SSID. So if
 495                  * the one we're looking at right now has that,
 496                  * return 0. Otherwise, return the difference
 497                  * in length, but since we're looking for the
 498                  * 0-length it's really equivalent to returning
 499                  * the length of the one we're looking at.
 500                  *
 501                  * No content comparison is needed as we assume
 502                  * the content length is zero.
 503                  */
 504                 return ie2[1];
 505         case BSS_CMP_REGULAR:
 506         default:
 507                 /* sort by length first, then by contents */
 508                 if (ie1[1] != ie2[1])
 509                         return ie2[1] - ie1[1];
 510                 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
 511         case BSS_CMP_HIDE_NUL:
 512                 if (ie1[1] != ie2[1])
 513                         return ie2[1] - ie1[1];
 514                 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
 515                 for (i = 0; i < ie2[1]; i++)
 516                         if (ie2[i + 2])
 517                                 return -1;
 518                 return 0;
 519         }
 520 }
 521
 522 /* Returned bss is reference counted and must be cleaned up appropriately. */
 523 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
 524                                       struct ieee80211_channel *channel,
 525                                       const u8 *bssid,
 526                                       const u8 *ssid, size_t ssid_len,
 527                                       u16 capa_mask, u16 capa_val)
 528 {
 529         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 530         struct cfg80211_internal_bss *bss, *res = NULL;
 531         unsigned long now = jiffies;
 532
 533         trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, capa_mask,
 534                                capa_val);
 535
 536         spin_lock_bh(&dev->bss_lock);
 537
 538         list_for_each_entry(bss, &dev->bss_list, list) {
 539                 if ((bss->pub.capability & capa_mask) != capa_val)
 540                         continue;
 541                 if (channel && bss->pub.channel != channel)
 542                         continue;
 543                 /* Don't get expired BSS structs */
 544                 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
 545                     !atomic_read(&bss->hold))
 546                         continue;
 547                 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
 548                         res = bss;
 549                         bss_ref_get(dev, res);
 550                         break;
 551                 }
 552         }
 553
 554         spin_unlock_bh(&dev->bss_lock);
 555         if (!res)
 556                 return NULL;
 557         trace_cfg80211_return_bss(&res->pub);
 558         return &res->pub;
 559 }
 560 EXPORT_SYMBOL(cfg80211_get_bss);
 561
 562 static void rb_insert_bss(struct cfg80211_registered_device *dev,
 563                           struct cfg80211_internal_bss *bss)
 564 {
 565         struct rb_node **p = &dev->bss_tree.rb_node;
 566         struct rb_node *parent = NULL;
 567         struct cfg80211_internal_bss *tbss;
 568         int cmp;
 569
 570         while (*p) {
 571                 parent = *p;
 572                 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
 573
 574                 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
 575
 576                 if (WARN_ON(!cmp)) {
 577                         /* will sort of leak this BSS */
 578                         return;
 579                 }
 580
 581                 if (cmp < 0)
 582                         p = &(*p)->rb_left;
 583                 else
 584                         p = &(*p)->rb_right;
 585         }
 586
 587         rb_link_node(&bss->rbn, parent, p);
 588         rb_insert_color(&bss->rbn, &dev->bss_tree);
 589 }
 590
 591 static struct cfg80211_internal_bss *
 592 rb_find_bss(struct cfg80211_registered_device *dev,
 593             struct cfg80211_internal_bss *res,
 594             enum bss_compare_mode mode)
 595 {
 596         struct rb_node *n = dev->bss_tree.rb_node;
 597         struct cfg80211_internal_bss *bss;
 598         int r;
 599
 600         while (n) {
 601                 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
 602                 r = cmp_bss(&res->pub, &bss->pub, mode);
 603
 604                 if (r == 0)
 605                         return bss;
 606                 else if (r < 0)
 607                         n = n->rb_left;
 608                 else
 609                         n = n->rb_right;
 610         }
 611
 612         return NULL;
 613 }
 614
 615 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *dev,
 616                                    struct cfg80211_internal_bss *new)
 617 {
 618         const struct cfg80211_bss_ies *ies;
 619         struct cfg80211_internal_bss *bss;
 620         const u8 *ie;
 621         int i, ssidlen;
 622         u8 fold = 0;
 623
 624         ies = rcu_access_pointer(new->pub.beacon_ies);
 625         if (WARN_ON(!ies))
 626                 return false;
 627
 628         ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
 629         if (!ie) {
 630                 /* nothing to do */
 631                 return true;
 632         }
 633
 634         ssidlen = ie[1];
 635         for (i = 0; i < ssidlen; i++)
 636                 fold |= ie[2 + i];
 637
 638         if (fold) {
 639                 /* not a hidden SSID */
 640                 return true;
 641         }
 642
 643         /* This is the bad part ... */
 644
 645         list_for_each_entry(bss, &dev->bss_list, list) {
 646                 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
 647                         continue;
 648                 if (bss->pub.channel != new->pub.channel)
 649                         continue;
 650                 if (bss->pub.scan_width != new->pub.scan_width)
 651                         continue;
 652                 if (rcu_access_pointer(bss->pub.beacon_ies))
 653                         continue;
 654                 ies = rcu_access_pointer(bss->pub.ies);
 655                 if (!ies)
 656                         continue;
 657                 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
 658                 if (!ie)
 659                         continue;
 660                 if (ssidlen && ie[1] != ssidlen)
 661                         continue;
 662                 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
 663                         continue;
 664                 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
 665                         list_del(&bss->hidden_list);
 666                 /* combine them */
 667                 list_add(&bss->hidden_list, &new->hidden_list);
 668                 bss->pub.hidden_beacon_bss = &new->pub;
 669                 new->refcount += bss->refcount;
 670                 rcu_assign_pointer(bss->pub.beacon_ies,
 671                                    new->pub.beacon_ies);
 672         }
 673
 674         return true;
 675 }
 676
 677 /* Returned bss is reference counted and must be cleaned up appropriately. */
 678 static struct cfg80211_internal_bss *
 679 cfg80211_bss_update(struct cfg80211_registered_device *dev,
 680                     struct cfg80211_internal_bss *tmp,
 681                     bool signal_valid)
 682 {
 683         struct cfg80211_internal_bss *found = NULL;
 684
 685         if (WARN_ON(!tmp->pub.channel))
 686                 return NULL;
 687
 688         tmp->ts = jiffies;
 689
 690         spin_lock_bh(&dev->bss_lock);
 691
 692         if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
 693                 spin_unlock_bh(&dev->bss_lock);
 694                 return NULL;
 695         }
 696
 697         found = rb_find_bss(dev, tmp, BSS_CMP_REGULAR);
 698
 699         if (found) {
 700                 /* Update IEs */
 701                 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
 702                         const struct cfg80211_bss_ies *old;
 703
 704                         old = rcu_access_pointer(found->pub.proberesp_ies);
 705
 706                         rcu_assign_pointer(found->pub.proberesp_ies,
 707                                            tmp->pub.proberesp_ies);
 708                         /* Override possible earlier Beacon frame IEs */
 709                         rcu_assign_pointer(found->pub.ies,
 710                                            tmp->pub.proberesp_ies);
 711                         if (old)
 712                                 kfree_rcu((struct cfg80211_bss_ies *)old,
 713                                           rcu_head);
 714                 } else if (rcu_access_pointer(tmp->pub.beacon_ies)) {
 715                         const struct cfg80211_bss_ies *old;
 716                         struct cfg80211_internal_bss *bss;
 717
 718                         if (found->pub.hidden_beacon_bss &&
 719                             !list_empty(&found->hidden_list)) {
 720                                 const struct cfg80211_bss_ies *f;
 721
 722                                 /*
 723                                  * The found BSS struct is one of the probe
 724                                  * response members of a group, but we're
 725                                  * receiving a beacon (beacon_ies in the tmp
 726                                  * bss is used). This can only mean that the
 727                                  * AP changed its beacon from not having an
 728                                  * SSID to showing it, which is confusing so
 729                                  * drop this information.
 730                                  */
 731
 732                                 f = rcu_access_pointer(tmp->pub.beacon_ies);
 733                                 kfree_rcu((struct cfg80211_bss_ies *)f,
 734                                           rcu_head);
 735                                 goto drop;
 736                         }
 737
 738                         old = rcu_access_pointer(found->pub.beacon_ies);
 739
 740                         rcu_assign_pointer(found->pub.beacon_ies,
 741                                            tmp->pub.beacon_ies);
 742
 743                         /* Override IEs if they were from a beacon before */
 744                         if (old == rcu_access_pointer(found->pub.ies))
 745                                 rcu_assign_pointer(found->pub.ies,
 746                                                    tmp->pub.beacon_ies);
 747
 748                         /* Assign beacon IEs to all sub entries */
 749                         list_for_each_entry(bss, &found->hidden_list,
 750                                             hidden_list) {
 751                                 const struct cfg80211_bss_ies *ies;
 752
 753                                 ies = rcu_access_pointer(bss->pub.beacon_ies);
 754                                 WARN_ON(ies != old);
 755
 756                                 rcu_assign_pointer(bss->pub.beacon_ies,
 757                                                    tmp->pub.beacon_ies);
 758                         }
 759
 760                         if (old)
 761                                 kfree_rcu((struct cfg80211_bss_ies *)old,
 762                                           rcu_head);
 763                 }
 764
 765                 found->pub.beacon_interval = tmp->pub.beacon_interval;
 766                 /*
 767                  * don't update the signal if beacon was heard on
 768                  * adjacent channel.
 769                  */
 770                 if (signal_valid)
 771                         found->pub.signal = tmp->pub.signal;
 772                 found->pub.capability = tmp->pub.capability;
 773                 found->ts = tmp->ts;
 774         } else {
 775                 struct cfg80211_internal_bss *new;
 776                 struct cfg80211_internal_bss *hidden;
 777                 struct cfg80211_bss_ies *ies;
 778
 779                 /*
 780                  * create a copy -- the "res" variable that is passed in
 781                  * is allocated on the stack since it's not needed in the
 782                  * more common case of an update
 783                  */
 784                 new = kzalloc(sizeof(*new) + dev->wiphy.bss_priv_size,
 785                               GFP_ATOMIC);
 786                 if (!new) {
 787                         ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
 788                         if (ies)
 789                                 kfree_rcu(ies, rcu_head);
 790                         ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
 791                         if (ies)
 792                                 kfree_rcu(ies, rcu_head);
 793                         goto drop;
 794                 }
 795                 memcpy(new, tmp, sizeof(*new));
 796                 new->refcount = 1;
 797                 INIT_LIST_HEAD(&new->hidden_list);
 798
 799                 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
 800                         hidden = rb_find_bss(dev, tmp, BSS_CMP_HIDE_ZLEN);
 801                         if (!hidden)
 802                                 hidden = rb_find_bss(dev, tmp,
 803                                                      BSS_CMP_HIDE_NUL);
 804                         if (hidden) {
 805                                 new->pub.hidden_beacon_bss = &hidden->pub;
 806                                 list_add(&new->hidden_list,
 807                                          &hidden->hidden_list);
 808                                 hidden->refcount++;
 809                                 rcu_assign_pointer(new->pub.beacon_ies,
 810                                                    hidden->pub.beacon_ies);
 811                         }
 812                 } else {
 813                         /*
 814                          * Ok so we found a beacon, and don't have an entry. If
 815                          * it's a beacon with hidden SSID, we might be in for an
 816                          * expensive search for any probe responses that should
 817                          * be grouped with this beacon for updates ...
 818                          */
 819                         if (!cfg80211_combine_bsses(dev, new)) {
 820                                 kfree(new);
 821                                 goto drop;
 822                         }
 823                 }
 824
 825                 list_add_tail(&new->list, &dev->bss_list);
 826                 rb_insert_bss(dev, new);
 827                 found = new;
 828         }
 829
 830         dev->bss_generation++;
 831         bss_ref_get(dev, found);
 832         spin_unlock_bh(&dev->bss_lock);
 833
 834         return found;
 835  drop:
 836         spin_unlock_bh(&dev->bss_lock);
 837         return NULL;
 838 }
 839
 840 static struct ieee80211_channel *
 841 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
 842                          struct ieee80211_channel *channel)
 843 {
 844         const u8 *tmp;
 845         u32 freq;
 846         int channel_number = -1;
 847
 848         tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen);
 849         if (tmp && tmp[1] == 1) {
 850                 channel_number = tmp[2];
 851         } else {
 852                 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen);
 853                 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) {
 854                         struct ieee80211_ht_operation *htop = (void *)(tmp + 2);
 855
 856                         channel_number = htop->primary_chan;
 857                 }
 858         }
 859
 860         if (channel_number < 0)
 861                 return channel;
 862
 863         freq = ieee80211_channel_to_frequency(channel_number, channel->band);
 864         channel = ieee80211_get_channel(wiphy, freq);
 865         if (!channel)
 866                 return NULL;
 867         if (channel->flags & IEEE80211_CHAN_DISABLED)
 868                 return NULL;
 869         return channel;
 870 }
 871
 872 /* Returned bss is reference counted and must be cleaned up appropriately. */
 873 struct cfg80211_bss*
 874 cfg80211_inform_bss_width(struct wiphy *wiphy,
 875                           struct ieee80211_channel *rx_channel,
 876                           enum nl80211_bss_scan_width scan_width,
 877                           const u8 *bssid, u64 tsf, u16 capability,
 878                           u16 beacon_interval, const u8 *ie, size_t ielen,
 879                           s32 signal, gfp_t gfp)
 880 {
 881         struct cfg80211_bss_ies *ies;
 882         struct ieee80211_channel *channel;
 883         struct cfg80211_internal_bss tmp = {}, *res;
 884
 885         if (WARN_ON(!wiphy))
 886                 return NULL;
 887
 888         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
 889                         (signal < 0 || signal > 100)))
 890                 return NULL;
 891
 892         channel = cfg80211_get_bss_channel(wiphy, ie, ielen, rx_channel);
 893         if (!channel)
 894                 return NULL;
 895
 896         memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
 897         tmp.pub.channel = channel;
 898         tmp.pub.scan_width = scan_width;
 899         tmp.pub.signal = signal;
 900         tmp.pub.beacon_interval = beacon_interval;
 901         tmp.pub.capability = capability;
 902         /*
 903          * Since we do not know here whether the IEs are from a Beacon or Probe
 904          * Response frame, we need to pick one of the options and only use it
 905          * with the driver that does not provide the full Beacon/Probe Response
 906          * frame. Use Beacon frame pointer to avoid indicating that this should
 907          * override the IEs pointer should we have received an earlier
 908          * indication of Probe Response data.
 909          */
 910         ies = kmalloc(sizeof(*ies) + ielen, gfp);
 911         if (!ies)
 912                 return NULL;
 913         ies->len = ielen;
 914         ies->tsf = tsf;
 915         memcpy(ies->data, ie, ielen);
 916
 917         rcu_assign_pointer(tmp.pub.beacon_ies, ies);
 918         rcu_assign_pointer(tmp.pub.ies, ies);
 919
 920         res = cfg80211_bss_update(wiphy_to_dev(wiphy), &tmp,
 921                                   rx_channel == channel);
 922         if (!res)
 923                 return NULL;
 924
 925         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 926                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 927
 928         trace_cfg80211_return_bss(&res->pub);
 929         /* cfg80211_bss_update gives us a referenced result */
 930         return &res->pub;
 931 }
 932 EXPORT_SYMBOL(cfg80211_inform_bss_width);
 933
 934 /* Returned bss is reference counted and must be cleaned up appropriately. */
 935 struct cfg80211_bss *
 936 cfg80211_inform_bss_width_frame(struct wiphy *wiphy,
 937                                 struct ieee80211_channel *rx_channel,
 938                                 enum nl80211_bss_scan_width scan_width,
 939                                 struct ieee80211_mgmt *mgmt, size_t len,
 940                                 s32 signal, gfp_t gfp)
 941 {
 942         struct cfg80211_internal_bss tmp = {}, *res;
 943         struct cfg80211_bss_ies *ies;
 944         struct ieee80211_channel *channel;
 945         size_t ielen = len - offsetof(struct ieee80211_mgmt,
 946                                       u.probe_resp.variable);
 947
 948         BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
 949                         offsetof(struct ieee80211_mgmt, u.beacon.variable));
 950
 951         trace_cfg80211_inform_bss_width_frame(wiphy, rx_channel, scan_width, mgmt,
 952                                               len, signal);
 953
 954         if (WARN_ON(!mgmt))
 955                 return NULL;
 956
 957         if (WARN_ON(!wiphy))
 958                 return NULL;
 959
 960         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
 961                     (signal < 0 || signal > 100)))
 962                 return NULL;
 963
 964         if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
 965                 return NULL;
 966
 967         channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable,
 968                                            ielen, rx_channel);
 969         if (!channel)
 970                 return NULL;
 971
 972         ies = kmalloc(sizeof(*ies) + ielen, gfp);
 973         if (!ies)
 974                 return NULL;
 975         ies->len = ielen;
 976         ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
 977         memcpy(ies->data, mgmt->u.probe_resp.variable, ielen);
 978
 979         if (ieee80211_is_probe_resp(mgmt->frame_control))
 980                 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
 981         else
 982                 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
 983         rcu_assign_pointer(tmp.pub.ies, ies);
 984
 985         memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN);
 986         tmp.pub.channel = channel;
 987         tmp.pub.scan_width = scan_width;
 988         tmp.pub.signal = signal;
 989         tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
 990         tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
 991
 992         res = cfg80211_bss_update(wiphy_to_dev(wiphy), &tmp,
 993                                   rx_channel == channel);
 994         if (!res)
 995                 return NULL;
 996
 997         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 998                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 999
1000         trace_cfg80211_return_bss(&res->pub);
1001         /* cfg80211_bss_update gives us a referenced result */
1002         return &res->pub;
1003 }
1004 EXPORT_SYMBOL(cfg80211_inform_bss_width_frame);
1005
1006 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1007 {
1008         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
1009         struct cfg80211_internal_bss *bss;
1010
1011         if (!pub)
1012                 return;
1013
1014         bss = container_of(pub, struct cfg80211_internal_bss, pub);
1015
1016         spin_lock_bh(&dev->bss_lock);
1017         bss_ref_get(dev, bss);
1018         spin_unlock_bh(&dev->bss_lock);
1019 }
1020 EXPORT_SYMBOL(cfg80211_ref_bss);
1021
1022 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1023 {
1024         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
1025         struct cfg80211_internal_bss *bss;
1026
1027         if (!pub)
1028                 return;
1029
1030         bss = container_of(pub, struct cfg80211_internal_bss, pub);
1031
1032         spin_lock_bh(&dev->bss_lock);
1033         bss_ref_put(dev, bss);
1034         spin_unlock_bh(&dev->bss_lock);
1035 }
1036 EXPORT_SYMBOL(cfg80211_put_bss);
1037
1038 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1039 {
1040         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
1041         struct cfg80211_internal_bss *bss;
1042
1043         if (WARN_ON(!pub))
1044                 return;
1045
1046         bss = container_of(pub, struct cfg80211_internal_bss, pub);
1047
1048         spin_lock_bh(&dev->bss_lock);
1049         if (!list_empty(&bss->list)) {
1050                 if (__cfg80211_unlink_bss(dev, bss))
1051                         dev->bss_generation++;
1052         }
1053         spin_unlock_bh(&dev->bss_lock);
1054 }
1055 EXPORT_SYMBOL(cfg80211_unlink_bss);
1056
1057 #ifdef CONFIG_CFG80211_WEXT
1058 static struct cfg80211_registered_device *
1059 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
1060 {
1061         struct cfg80211_registered_device *rdev;
1062         struct net_device *dev;
1063
1064         ASSERT_RTNL();
1065
1066         dev = dev_get_by_index(net, ifindex);
1067         if (!dev)
1068                 return ERR_PTR(-ENODEV);
1069         if (dev->ieee80211_ptr)
1070                 rdev = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
1071         else
1072                 rdev = ERR_PTR(-ENODEV);
1073         dev_put(dev);
1074         return rdev;
1075 }
1076
1077 int cfg80211_wext_siwscan(struct net_device *dev,
1078                           struct iw_request_info *info,
1079                           union iwreq_data *wrqu, char *extra)
1080 {
1081         struct cfg80211_registered_device *rdev;
1082         struct wiphy *wiphy;
1083         struct iw_scan_req *wreq = NULL;
1084         struct cfg80211_scan_request *creq = NULL;
1085         int i, err, n_channels = 0;
1086         enum ieee80211_band band;
1087
1088         if (!netif_running(dev))
1089                 return -ENETDOWN;
1090
1091         if (wrqu->data.length == sizeof(struct iw_scan_req))
1092                 wreq = (struct iw_scan_req *)extra;
1093
1094         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1095
1096         if (IS_ERR(rdev))
1097                 return PTR_ERR(rdev);
1098
1099         if (rdev->scan_req || rdev->scan_msg) {
1100                 err = -EBUSY;
1101                 goto out;
1102         }
1103
1104         wiphy = &rdev->wiphy;
1105
1106         /* Determine number of channels, needed to allocate creq */
1107         if (wreq && wreq->num_channels)
1108                 n_channels = wreq->num_channels;
1109         else
1110                 n_channels = ieee80211_get_num_supported_channels(wiphy);
1111
1112         creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
1113                        n_channels * sizeof(void *),
1114                        GFP_ATOMIC);
1115         if (!creq) {
1116                 err = -ENOMEM;
1117                 goto out;
1118         }
1119
1120         creq->wiphy = wiphy;
1121         creq->wdev = dev->ieee80211_ptr;
1122         /* SSIDs come after channels */
1123         creq->ssids = (void *)&creq->channels[n_channels];
1124         creq->n_channels = n_channels;
1125         creq->n_ssids = 1;
1126         creq->scan_start = jiffies;
1127
1128         /* translate "Scan on frequencies" request */
1129         i = 0;
1130         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1131                 int j;
1132
1133                 if (!wiphy->bands[band])
1134                         continue;
1135
1136                 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
1137                         /* ignore disabled channels */
1138                         if (wiphy->bands[band]->channels[j].flags &
1139                                                 IEEE80211_CHAN_DISABLED)
1140                                 continue;
1141
1142                         /* If we have a wireless request structure and the
1143                          * wireless request specifies frequencies, then search
1144                          * for the matching hardware channel.
1145                          */
1146                         if (wreq && wreq->num_channels) {
1147                                 int k;
1148                                 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
1149                                 for (k = 0; k < wreq->num_channels; k++) {
1150                                         int wext_freq = cfg80211_wext_freq(wiphy, &wreq->channel_list[k]);
1151                                         if (wext_freq == wiphy_freq)
1152                                                 goto wext_freq_found;
1153                                 }
1154                                 goto wext_freq_not_found;
1155                         }
1156
1157                 wext_freq_found:
1158                         creq->channels[i] = &wiphy->bands[band]->channels[j];
1159                         i++;
1160                 wext_freq_not_found: ;
1161                 }
1162         }
1163         /* No channels found? */
1164         if (!i) {
1165                 err = -EINVAL;
1166                 goto out;
1167         }
1168
1169         /* Set real number of channels specified in creq->channels[] */
1170         creq->n_channels = i;
1171
1172         /* translate "Scan for SSID" request */
1173         if (wreq) {
1174                 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
1175                         if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
1176                                 err = -EINVAL;
1177                                 goto out;
1178                         }
1179                         memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
1180                         creq->ssids[0].ssid_len = wreq->essid_len;
1181                 }
1182                 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
1183                         creq->n_ssids = 0;
1184         }
1185
1186         for (i = 0; i < IEEE80211_NUM_BANDS; i++)
1187                 if (wiphy->bands[i])
1188                         creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
1189
1190         rdev->scan_req = creq;
1191         err = rdev_scan(rdev, creq);
1192         if (err) {
1193                 rdev->scan_req = NULL;
1194                 /* creq will be freed below */
1195         } else {
1196                 nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
1197                 /* creq now owned by driver */
1198                 creq = NULL;
1199                 dev_hold(dev);
1200         }
1201  out:
1202         kfree(creq);
1203         return err;
1204 }
1205 EXPORT_SYMBOL_GPL(cfg80211_wext_siwscan);
1206
1207 static void ieee80211_scan_add_ies(struct iw_request_info *info,
1208                                    const struct cfg80211_bss_ies *ies,
1209                                    char **current_ev, char *end_buf)
1210 {
1211         const u8 *pos, *end, *next;
1212         struct iw_event iwe;
1213
1214         if (!ies)
1215                 return;
1216
1217         /*
1218          * If needed, fragment the IEs buffer (at IE boundaries) into short
1219          * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
1220          */
1221         pos = ies->data;
1222         end = pos + ies->len;
1223
1224         while (end - pos > IW_GENERIC_IE_MAX) {
1225                 next = pos + 2 + pos[1];
1226                 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
1227                         next = next + 2 + next[1];
1228
1229                 memset(&iwe, 0, sizeof(iwe));
1230                 iwe.cmd = IWEVGENIE;
1231                 iwe.u.data.length = next - pos;
1232                 *current_ev = iwe_stream_add_point(info, *current_ev,
1233                                                    end_buf, &iwe,
1234                                                    (void *)pos);
1235
1236                 pos = next;
1237         }
1238
1239         if (end > pos) {
1240                 memset(&iwe, 0, sizeof(iwe));
1241                 iwe.cmd = IWEVGENIE;
1242                 iwe.u.data.length = end - pos;
1243                 *current_ev = iwe_stream_add_point(info, *current_ev,
1244                                                    end_buf, &iwe,
1245                                                    (void *)pos);
1246         }
1247 }
1248
1249 static char *
1250 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
1251               struct cfg80211_internal_bss *bss, char *current_ev,
1252               char *end_buf)
1253 {
1254         const struct cfg80211_bss_ies *ies;
1255         struct iw_event iwe;
1256         const u8 *ie;
1257         u8 *buf, *cfg, *p;
1258         int rem, i, sig;
1259         bool ismesh = false;
1260
1261         memset(&iwe, 0, sizeof(iwe));
1262         iwe.cmd = SIOCGIWAP;
1263         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
1264         memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
1265         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1266                                           IW_EV_ADDR_LEN);
1267
1268         memset(&iwe, 0, sizeof(iwe));
1269         iwe.cmd = SIOCGIWFREQ;
1270         iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
1271         iwe.u.freq.e = 0;
1272         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1273                                           IW_EV_FREQ_LEN);
1274
1275         memset(&iwe, 0, sizeof(iwe));
1276         iwe.cmd = SIOCGIWFREQ;
1277         iwe.u.freq.m = bss->pub.channel->center_freq;
1278         iwe.u.freq.e = 6;
1279         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1280                                           IW_EV_FREQ_LEN);
1281
1282         if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
1283                 memset(&iwe, 0, sizeof(iwe));
1284                 iwe.cmd = IWEVQUAL;
1285                 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
1286                                      IW_QUAL_NOISE_INVALID |
1287                                      IW_QUAL_QUAL_UPDATED;
1288                 switch (wiphy->signal_type) {
1289                 case CFG80211_SIGNAL_TYPE_MBM:
1290                         sig = bss->pub.signal / 100;
1291                         iwe.u.qual.level = sig;
1292                         iwe.u.qual.updated |= IW_QUAL_DBM;
1293                         if (sig < -110)         /* rather bad */
1294                                 sig = -110;
1295                         else if (sig > -40)     /* perfect */
1296                                 sig = -40;
1297                         /* will give a range of 0 .. 70 */
1298                         iwe.u.qual.qual = sig + 110;
1299                         break;
1300                 case CFG80211_SIGNAL_TYPE_UNSPEC:
1301                         iwe.u.qual.level = bss->pub.signal;
1302                         /* will give range 0 .. 100 */
1303                         iwe.u.qual.qual = bss->pub.signal;
1304                         break;
1305                 default:
1306                         /* not reached */
1307                         break;
1308                 }
1309                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1310                                                   &iwe, IW_EV_QUAL_LEN);
1311         }
1312
1313         memset(&iwe, 0, sizeof(iwe));
1314         iwe.cmd = SIOCGIWENCODE;
1315         if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
1316                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
1317         else
1318                 iwe.u.data.flags = IW_ENCODE_DISABLED;
1319         iwe.u.data.length = 0;
1320         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1321                                           &iwe, "");
1322
1323         rcu_read_lock();
1324         ies = rcu_dereference(bss->pub.ies);
1325         rem = ies->len;
1326         ie = ies->data;
1327
1328         while (rem >= 2) {
1329                 /* invalid data */
1330                 if (ie[1] > rem - 2)
1331                         break;
1332
1333                 switch (ie[0]) {
1334                 case WLAN_EID_SSID:
1335                         memset(&iwe, 0, sizeof(iwe));
1336                         iwe.cmd = SIOCGIWESSID;
1337                         iwe.u.data.length = ie[1];
1338                         iwe.u.data.flags = 1;
1339                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1340                                                           &iwe, (u8 *)ie + 2);
1341                         break;
1342                 case WLAN_EID_MESH_ID:
1343                         memset(&iwe, 0, sizeof(iwe));
1344                         iwe.cmd = SIOCGIWESSID;
1345                         iwe.u.data.length = ie[1];
1346                         iwe.u.data.flags = 1;
1347                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1348                                                           &iwe, (u8 *)ie + 2);
1349                         break;
1350                 case WLAN_EID_MESH_CONFIG:
1351                         ismesh = true;
1352                         if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
1353                                 break;
1354                         buf = kmalloc(50, GFP_ATOMIC);
1355                         if (!buf)
1356                                 break;
1357                         cfg = (u8 *)ie + 2;
1358                         memset(&iwe, 0, sizeof(iwe));
1359                         iwe.cmd = IWEVCUSTOM;
1360                         sprintf(buf, "Mesh Network Path Selection Protocol ID: "
1361                                 "0x%02X", cfg[0]);
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, "Path Selection Metric ID: 0x%02X",
1367                                 cfg[1]);
1368                         iwe.u.data.length = strlen(buf);
1369                         current_ev = iwe_stream_add_point(info, current_ev,
1370                                                           end_buf,
1371                                                           &iwe, buf);
1372                         sprintf(buf, "Congestion Control Mode ID: 0x%02X",
1373                                 cfg[2]);
1374                         iwe.u.data.length = strlen(buf);
1375                         current_ev = iwe_stream_add_point(info, current_ev,
1376                                                           end_buf,
1377                                                           &iwe, buf);
1378                         sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
1379                         iwe.u.data.length = strlen(buf);
1380                         current_ev = iwe_stream_add_point(info, current_ev,
1381                                                           end_buf,
1382                                                           &iwe, buf);
1383                         sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
1384                         iwe.u.data.length = strlen(buf);
1385                         current_ev = iwe_stream_add_point(info, current_ev,
1386                                                           end_buf,
1387                                                           &iwe, buf);
1388                         sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
1389                         iwe.u.data.length = strlen(buf);
1390                         current_ev = iwe_stream_add_point(info, current_ev,
1391                                                           end_buf,
1392                                                           &iwe, buf);
1393                         sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
1394                         iwe.u.data.length = strlen(buf);
1395                         current_ev = iwe_stream_add_point(info, current_ev,
1396                                                           end_buf,
1397                                                           &iwe, buf);
1398                         kfree(buf);
1399                         break;
1400                 case WLAN_EID_SUPP_RATES:
1401                 case WLAN_EID_EXT_SUPP_RATES:
1402                         /* display all supported rates in readable format */
1403                         p = current_ev + iwe_stream_lcp_len(info);
1404
1405                         memset(&iwe, 0, sizeof(iwe));
1406                         iwe.cmd = SIOCGIWRATE;
1407                         /* Those two flags are ignored... */
1408                         iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
1409
1410                         for (i = 0; i < ie[1]; i++) {
1411                                 iwe.u.bitrate.value =
1412                                         ((ie[i + 2] & 0x7f) * 500000);
1413                                 p = iwe_stream_add_value(info, current_ev, p,
1414                                                 end_buf, &iwe, IW_EV_PARAM_LEN);
1415                         }
1416                         current_ev = p;
1417                         break;
1418                 }
1419                 rem -= ie[1] + 2;
1420                 ie += ie[1] + 2;
1421         }
1422
1423         if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
1424             ismesh) {
1425                 memset(&iwe, 0, sizeof(iwe));
1426                 iwe.cmd = SIOCGIWMODE;
1427                 if (ismesh)
1428                         iwe.u.mode = IW_MODE_MESH;
1429                 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
1430                         iwe.u.mode = IW_MODE_MASTER;
1431                 else
1432                         iwe.u.mode = IW_MODE_ADHOC;
1433                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1434                                                   &iwe, IW_EV_UINT_LEN);
1435         }
1436
1437         buf = kmalloc(31, GFP_ATOMIC);
1438         if (buf) {
1439                 memset(&iwe, 0, sizeof(iwe));
1440                 iwe.cmd = IWEVCUSTOM;
1441                 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
1442                 iwe.u.data.length = strlen(buf);
1443                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1444                                                   &iwe, buf);
1445                 memset(&iwe, 0, sizeof(iwe));
1446                 iwe.cmd = IWEVCUSTOM;
1447                 sprintf(buf, " Last beacon: %ums ago",
1448                         elapsed_jiffies_msecs(bss->ts));
1449                 iwe.u.data.length = strlen(buf);
1450                 current_ev = iwe_stream_add_point(info, current_ev,
1451                                                   end_buf, &iwe, buf);
1452                 kfree(buf);
1453         }
1454
1455         ieee80211_scan_add_ies(info, ies, &current_ev, end_buf);
1456         rcu_read_unlock();
1457
1458         return current_ev;
1459 }
1460
1461
1462 static int ieee80211_scan_results(struct cfg80211_registered_device *dev,
1463                                   struct iw_request_info *info,
1464                                   char *buf, size_t len)
1465 {
1466         char *current_ev = buf;
1467         char *end_buf = buf + len;
1468         struct cfg80211_internal_bss *bss;
1469
1470         spin_lock_bh(&dev->bss_lock);
1471         cfg80211_bss_expire(dev);
1472
1473         list_for_each_entry(bss, &dev->bss_list, list) {
1474                 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
1475                         spin_unlock_bh(&dev->bss_lock);
1476                         return -E2BIG;
1477                 }
1478                 current_ev = ieee80211_bss(&dev->wiphy, info, bss,
1479                                            current_ev, end_buf);
1480         }
1481         spin_unlock_bh(&dev->bss_lock);
1482         return current_ev - buf;
1483 }
1484
1485
1486 int cfg80211_wext_giwscan(struct net_device *dev,
1487                           struct iw_request_info *info,
1488                           struct iw_point *data, char *extra)
1489 {
1490         struct cfg80211_registered_device *rdev;
1491         int res;
1492
1493         if (!netif_running(dev))
1494                 return -ENETDOWN;
1495
1496         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1497
1498         if (IS_ERR(rdev))
1499                 return PTR_ERR(rdev);
1500
1501         if (rdev->scan_req || rdev->scan_msg)
1502                 return -EAGAIN;
1503
1504         res = ieee80211_scan_results(rdev, info, extra, data->length);
1505         data->length = 0;
1506         if (res >= 0) {
1507                 data->length = res;
1508                 res = 0;
1509         }
1510
1511         return res;
1512 }
1513 EXPORT_SYMBOL_GPL(cfg80211_wext_giwscan);
1514 #endif