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, bool leak)
 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_RDEV_LOCK(rdev);
 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
 214         /*
 215          * OK. If this is invoked with "leak" then we can't
 216          * free this ... but we've cleaned it up anyway. The
 217          * driver failed to call the scan_done callback, so
 218          * all bets are off, it might still be trying to use
 219          * the scan request or not ... if it accesses the dev
 220          * in there (it shouldn't anyway) then it may crash.
 221          */
 222         if (!leak)
 223                 kfree(request);
 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         cfg80211_lock_rdev(rdev);
 234         ___cfg80211_scan_done(rdev, false);
 235         cfg80211_unlock_rdev(rdev);
 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         queue_work(cfg80211_wq, &wiphy_to_dev(request->wiphy)->scan_done_wk);
 245 }
 246 EXPORT_SYMBOL(cfg80211_scan_done);
 247
 248 void __cfg80211_sched_scan_results(struct work_struct *wk)
 249 {
 250         struct cfg80211_registered_device *rdev;
 251         struct cfg80211_sched_scan_request *request;
 252
 253         rdev = container_of(wk, struct cfg80211_registered_device,
 254                             sched_scan_results_wk);
 255
 256         request = rdev->sched_scan_req;
 257
 258         mutex_lock(&rdev->sched_scan_mtx);
 259
 260         /* we don't have sched_scan_req anymore if the scan is stopping */
 261         if (request) {
 262                 if (request->flags & NL80211_SCAN_FLAG_FLUSH) {
 263                         /* flush entries from previous scans */
 264                         spin_lock_bh(&rdev->bss_lock);
 265                         __cfg80211_bss_expire(rdev, request->scan_start);
 266                         spin_unlock_bh(&rdev->bss_lock);
 267                         request->scan_start =
 268                                 jiffies + msecs_to_jiffies(request->interval);
 269                 }
 270                 nl80211_send_sched_scan_results(rdev, request->dev);
 271         }
 272
 273         mutex_unlock(&rdev->sched_scan_mtx);
 274 }
 275
 276 void cfg80211_sched_scan_results(struct wiphy *wiphy)
 277 {
 278         trace_cfg80211_sched_scan_results(wiphy);
 279         /* ignore if we're not scanning */
 280         if (wiphy_to_dev(wiphy)->sched_scan_req)
 281                 queue_work(cfg80211_wq,
 282                            &wiphy_to_dev(wiphy)->sched_scan_results_wk);
 283 }
 284 EXPORT_SYMBOL(cfg80211_sched_scan_results);
 285
 286 void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
 287 {
 288         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
 289
 290         trace_cfg80211_sched_scan_stopped(wiphy);
 291
 292         mutex_lock(&rdev->sched_scan_mtx);
 293         __cfg80211_stop_sched_scan(rdev, true);
 294         mutex_unlock(&rdev->sched_scan_mtx);
 295 }
 296 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
 297
 298 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
 299                                bool driver_initiated)
 300 {
 301         struct net_device *dev;
 302
 303         lockdep_assert_held(&rdev->sched_scan_mtx);
 304
 305         if (!rdev->sched_scan_req)
 306                 return -ENOENT;
 307
 308         dev = rdev->sched_scan_req->dev;
 309
 310         if (!driver_initiated) {
 311                 int err = rdev_sched_scan_stop(rdev, dev);
 312                 if (err)
 313                         return err;
 314         }
 315
 316         nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED);
 317
 318         kfree(rdev->sched_scan_req);
 319         rdev->sched_scan_req = NULL;
 320
 321         return 0;
 322 }
 323
 324 void cfg80211_bss_age(struct cfg80211_registered_device *dev,
 325                       unsigned long age_secs)
 326 {
 327         struct cfg80211_internal_bss *bss;
 328         unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
 329
 330         spin_lock_bh(&dev->bss_lock);
 331         list_for_each_entry(bss, &dev->bss_list, list)
 332                 bss->ts -= age_jiffies;
 333         spin_unlock_bh(&dev->bss_lock);
 334 }
 335
 336 void cfg80211_bss_expire(struct cfg80211_registered_device *dev)
 337 {
 338         __cfg80211_bss_expire(dev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
 339 }
 340
 341 const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len)
 342 {
 343         while (len > 2 && ies[0] != eid) {
 344                 len -= ies[1] + 2;
 345                 ies += ies[1] + 2;
 346         }
 347         if (len < 2)
 348                 return NULL;
 349         if (len < 2 + ies[1])
 350                 return NULL;
 351         return ies;
 352 }
 353 EXPORT_SYMBOL(cfg80211_find_ie);
 354
 355 const u8 *cfg80211_find_vendor_ie(unsigned int oui, u8 oui_type,
 356                                   const u8 *ies, int len)
 357 {
 358         struct ieee80211_vendor_ie *ie;
 359         const u8 *pos = ies, *end = ies + len;
 360         int ie_oui;
 361
 362         while (pos < end) {
 363                 pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos,
 364                                        end - pos);
 365                 if (!pos)
 366                         return NULL;
 367
 368                 if (end - pos < sizeof(*ie))
 369                         return NULL;
 370
 371                 ie = (struct ieee80211_vendor_ie *)pos;
 372                 ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2];
 373                 if (ie_oui == oui && ie->oui_type == oui_type)
 374                         return pos;
 375
 376                 pos += 2 + ie->len;
 377         }
 378         return NULL;
 379 }
 380 EXPORT_SYMBOL(cfg80211_find_vendor_ie);
 381
 382 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
 383                    const u8 *ssid, size_t ssid_len)
 384 {
 385         const struct cfg80211_bss_ies *ies;
 386         const u8 *ssidie;
 387
 388         if (bssid && !ether_addr_equal(a->bssid, bssid))
 389                 return false;
 390
 391         if (!ssid)
 392                 return true;
 393
 394         ies = rcu_access_pointer(a->ies);
 395         if (!ies)
 396                 return false;
 397         ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
 398         if (!ssidie)
 399                 return false;
 400         if (ssidie[1] != ssid_len)
 401                 return false;
 402         return memcmp(ssidie + 2, ssid, ssid_len) == 0;
 403 }
 404
 405 /**
 406  * enum bss_compare_mode - BSS compare mode
 407  * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
 408  * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
 409  * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
 410  */
 411 enum bss_compare_mode {
 412         BSS_CMP_REGULAR,
 413         BSS_CMP_HIDE_ZLEN,
 414         BSS_CMP_HIDE_NUL,
 415 };
 416
 417 static int cmp_bss(struct cfg80211_bss *a,
 418                    struct cfg80211_bss *b,
 419                    enum bss_compare_mode mode)
 420 {
 421         const struct cfg80211_bss_ies *a_ies, *b_ies;
 422         const u8 *ie1 = NULL;
 423         const u8 *ie2 = NULL;
 424         int i, r;
 425
 426         if (a->channel != b->channel)
 427                 return b->channel->center_freq - a->channel->center_freq;
 428
 429         a_ies = rcu_access_pointer(a->ies);
 430         if (!a_ies)
 431                 return -1;
 432         b_ies = rcu_access_pointer(b->ies);
 433         if (!b_ies)
 434                 return 1;
 435
 436         if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
 437                 ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
 438                                        a_ies->data, a_ies->len);
 439         if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
 440                 ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
 441                                        b_ies->data, b_ies->len);
 442         if (ie1 && ie2) {
 443                 int mesh_id_cmp;
 444
 445                 if (ie1[1] == ie2[1])
 446                         mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
 447                 else
 448                         mesh_id_cmp = ie2[1] - ie1[1];
 449
 450                 ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
 451                                        a_ies->data, a_ies->len);
 452                 ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
 453                                        b_ies->data, b_ies->len);
 454                 if (ie1 && ie2) {
 455                         if (mesh_id_cmp)
 456                                 return mesh_id_cmp;
 457                         if (ie1[1] != ie2[1])
 458                                 return ie2[1] - ie1[1];
 459                         return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
 460                 }
 461         }
 462
 463         /*
 464          * we can't use compare_ether_addr here since we need a < > operator.
 465          * The binary return value of compare_ether_addr isn't enough
 466          */
 467         r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
 468         if (r)
 469                 return r;
 470
 471         ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
 472         ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
 473
 474         if (!ie1 && !ie2)
 475                 return 0;
 476
 477         /*
 478          * Note that with "hide_ssid", the function returns a match if
 479          * the already-present BSS ("b") is a hidden SSID beacon for
 480          * the new BSS ("a").
 481          */
 482
 483         /* sort missing IE before (left of) present IE */
 484         if (!ie1)
 485                 return -1;
 486         if (!ie2)
 487                 return 1;
 488
 489         switch (mode) {
 490         case BSS_CMP_HIDE_ZLEN:
 491                 /*
 492                  * In ZLEN mode we assume the BSS entry we're
 493                  * looking for has a zero-length SSID. So if
 494                  * the one we're looking at right now has that,
 495                  * return 0. Otherwise, return the difference
 496                  * in length, but since we're looking for the
 497                  * 0-length it's really equivalent to returning
 498                  * the length of the one we're looking at.
 499                  *
 500                  * No content comparison is needed as we assume
 501                  * the content length is zero.
 502                  */
 503                 return ie2[1];
 504         case BSS_CMP_REGULAR:
 505         default:
 506                 /* sort by length first, then by contents */
 507                 if (ie1[1] != ie2[1])
 508                         return ie2[1] - ie1[1];
 509                 return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
 510         case BSS_CMP_HIDE_NUL:
 511                 if (ie1[1] != ie2[1])
 512                         return ie2[1] - ie1[1];
 513                 /* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
 514                 for (i = 0; i < ie2[1]; i++)
 515                         if (ie2[i + 2])
 516                                 return -1;
 517                 return 0;
 518         }
 519 }
 520
 521 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
 522                                       struct ieee80211_channel *channel,
 523                                       const u8 *bssid,
 524                                       const u8 *ssid, size_t ssid_len,
 525                                       u16 capa_mask, u16 capa_val)
 526 {
 527         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 528         struct cfg80211_internal_bss *bss, *res = NULL;
 529         unsigned long now = jiffies;
 530
 531         trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, capa_mask,
 532                                capa_val);
 533
 534         spin_lock_bh(&dev->bss_lock);
 535
 536         list_for_each_entry(bss, &dev->bss_list, list) {
 537                 if ((bss->pub.capability & capa_mask) != capa_val)
 538                         continue;
 539                 if (channel && bss->pub.channel != channel)
 540                         continue;
 541                 /* Don't get expired BSS structs */
 542                 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
 543                     !atomic_read(&bss->hold))
 544                         continue;
 545                 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
 546                         res = bss;
 547                         bss_ref_get(dev, res);
 548                         break;
 549                 }
 550         }
 551
 552         spin_unlock_bh(&dev->bss_lock);
 553         if (!res)
 554                 return NULL;
 555         trace_cfg80211_return_bss(&res->pub);
 556         return &res->pub;
 557 }
 558 EXPORT_SYMBOL(cfg80211_get_bss);
 559
 560 static void rb_insert_bss(struct cfg80211_registered_device *dev,
 561                           struct cfg80211_internal_bss *bss)
 562 {
 563         struct rb_node **p = &dev->bss_tree.rb_node;
 564         struct rb_node *parent = NULL;
 565         struct cfg80211_internal_bss *tbss;
 566         int cmp;
 567
 568         while (*p) {
 569                 parent = *p;
 570                 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
 571
 572                 cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
 573
 574                 if (WARN_ON(!cmp)) {
 575                         /* will sort of leak this BSS */
 576                         return;
 577                 }
 578
 579                 if (cmp < 0)
 580                         p = &(*p)->rb_left;
 581                 else
 582                         p = &(*p)->rb_right;
 583         }
 584
 585         rb_link_node(&bss->rbn, parent, p);
 586         rb_insert_color(&bss->rbn, &dev->bss_tree);
 587 }
 588
 589 static struct cfg80211_internal_bss *
 590 rb_find_bss(struct cfg80211_registered_device *dev,
 591             struct cfg80211_internal_bss *res,
 592             enum bss_compare_mode mode)
 593 {
 594         struct rb_node *n = dev->bss_tree.rb_node;
 595         struct cfg80211_internal_bss *bss;
 596         int r;
 597
 598         while (n) {
 599                 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
 600                 r = cmp_bss(&res->pub, &bss->pub, mode);
 601
 602                 if (r == 0)
 603                         return bss;
 604                 else if (r < 0)
 605                         n = n->rb_left;
 606                 else
 607                         n = n->rb_right;
 608         }
 609
 610         return NULL;
 611 }
 612
 613 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *dev,
 614                                    struct cfg80211_internal_bss *new)
 615 {
 616         const struct cfg80211_bss_ies *ies;
 617         struct cfg80211_internal_bss *bss;
 618         const u8 *ie;
 619         int i, ssidlen;
 620         u8 fold = 0;
 621
 622         ies = rcu_access_pointer(new->pub.beacon_ies);
 623         if (WARN_ON(!ies))
 624                 return false;
 625
 626         ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
 627         if (!ie) {
 628                 /* nothing to do */
 629                 return true;
 630         }
 631
 632         ssidlen = ie[1];
 633         for (i = 0; i < ssidlen; i++)
 634                 fold |= ie[2 + i];
 635
 636         if (fold) {
 637                 /* not a hidden SSID */
 638                 return true;
 639         }
 640
 641         /* This is the bad part ... */
 642
 643         list_for_each_entry(bss, &dev->bss_list, list) {
 644                 if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
 645                         continue;
 646                 if (bss->pub.channel != new->pub.channel)
 647                         continue;
 648                 if (rcu_access_pointer(bss->pub.beacon_ies))
 649                         continue;
 650                 ies = rcu_access_pointer(bss->pub.ies);
 651                 if (!ies)
 652                         continue;
 653                 ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
 654                 if (!ie)
 655                         continue;
 656                 if (ssidlen && ie[1] != ssidlen)
 657                         continue;
 658                 /* that would be odd ... */
 659                 if (bss->pub.beacon_ies)
 660                         continue;
 661                 if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
 662                         continue;
 663                 if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
 664                         list_del(&bss->hidden_list);
 665                 /* combine them */
 666                 list_add(&bss->hidden_list, &new->hidden_list);
 667                 bss->pub.hidden_beacon_bss = &new->pub;
 668                 new->refcount += bss->refcount;
 669                 rcu_assign_pointer(bss->pub.beacon_ies,
 670                                    new->pub.beacon_ies);
 671         }
 672
 673         return true;
 674 }
 675
 676 static struct cfg80211_internal_bss *
 677 cfg80211_bss_update(struct cfg80211_registered_device *dev,
 678                     struct cfg80211_internal_bss *tmp)
 679 {
 680         struct cfg80211_internal_bss *found = NULL;
 681
 682         if (WARN_ON(!tmp->pub.channel))
 683                 return NULL;
 684
 685         tmp->ts = jiffies;
 686
 687         spin_lock_bh(&dev->bss_lock);
 688
 689         if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
 690                 spin_unlock_bh(&dev->bss_lock);
 691                 return NULL;
 692         }
 693
 694         found = rb_find_bss(dev, tmp, BSS_CMP_REGULAR);
 695
 696         if (found) {
 697                 found->pub.beacon_interval = tmp->pub.beacon_interval;
 698                 found->pub.signal = tmp->pub.signal;
 699                 found->pub.capability = tmp->pub.capability;
 700                 found->ts = tmp->ts;
 701
 702                 /* Update IEs */
 703                 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
 704                         const struct cfg80211_bss_ies *old;
 705
 706                         old = rcu_access_pointer(found->pub.proberesp_ies);
 707
 708                         rcu_assign_pointer(found->pub.proberesp_ies,
 709                                            tmp->pub.proberesp_ies);
 710                         /* Override possible earlier Beacon frame IEs */
 711                         rcu_assign_pointer(found->pub.ies,
 712                                            tmp->pub.proberesp_ies);
 713                         if (old)
 714                                 kfree_rcu((struct cfg80211_bss_ies *)old,
 715                                           rcu_head);
 716                 } else if (rcu_access_pointer(tmp->pub.beacon_ies)) {
 717                         const struct cfg80211_bss_ies *old;
 718                         struct cfg80211_internal_bss *bss;
 719
 720                         if (found->pub.hidden_beacon_bss &&
 721                             !list_empty(&found->hidden_list)) {
 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                                 goto drop;
 732                         }
 733
 734                         old = rcu_access_pointer(found->pub.beacon_ies);
 735
 736                         rcu_assign_pointer(found->pub.beacon_ies,
 737                                            tmp->pub.beacon_ies);
 738
 739                         /* Override IEs if they were from a beacon before */
 740                         if (old == rcu_access_pointer(found->pub.ies))
 741                                 rcu_assign_pointer(found->pub.ies,
 742                                                    tmp->pub.beacon_ies);
 743
 744                         /* Assign beacon IEs to all sub entries */
 745                         list_for_each_entry(bss, &found->hidden_list,
 746                                             hidden_list) {
 747                                 const struct cfg80211_bss_ies *ies;
 748
 749                                 ies = rcu_access_pointer(bss->pub.beacon_ies);
 750                                 WARN_ON(ies != old);
 751
 752                                 rcu_assign_pointer(bss->pub.beacon_ies,
 753                                                    tmp->pub.beacon_ies);
 754                         }
 755
 756                         if (old)
 757                                 kfree_rcu((struct cfg80211_bss_ies *)old,
 758                                           rcu_head);
 759                 }
 760         } else {
 761                 struct cfg80211_internal_bss *new;
 762                 struct cfg80211_internal_bss *hidden;
 763                 struct cfg80211_bss_ies *ies;
 764
 765                 /*
 766                  * create a copy -- the "res" variable that is passed in
 767                  * is allocated on the stack since it's not needed in the
 768                  * more common case of an update
 769                  */
 770                 new = kzalloc(sizeof(*new) + dev->wiphy.bss_priv_size,
 771                               GFP_ATOMIC);
 772                 if (!new) {
 773                         ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
 774                         if (ies)
 775                                 kfree_rcu(ies, rcu_head);
 776                         ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
 777                         if (ies)
 778                                 kfree_rcu(ies, rcu_head);
 779                         goto drop;
 780                 }
 781                 memcpy(new, tmp, sizeof(*new));
 782                 new->refcount = 1;
 783                 INIT_LIST_HEAD(&new->hidden_list);
 784
 785                 if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
 786                         hidden = rb_find_bss(dev, tmp, BSS_CMP_HIDE_ZLEN);
 787                         if (!hidden)
 788                                 hidden = rb_find_bss(dev, tmp,
 789                                                      BSS_CMP_HIDE_NUL);
 790                         if (hidden) {
 791                                 new->pub.hidden_beacon_bss = &hidden->pub;
 792                                 list_add(&new->hidden_list,
 793                                          &hidden->hidden_list);
 794                                 hidden->refcount++;
 795                                 rcu_assign_pointer(new->pub.beacon_ies,
 796                                                    hidden->pub.beacon_ies);
 797                         }
 798                 } else {
 799                         /*
 800                          * Ok so we found a beacon, and don't have an entry. If
 801                          * it's a beacon with hidden SSID, we might be in for an
 802                          * expensive search for any probe responses that should
 803                          * be grouped with this beacon for updates ...
 804                          */
 805                         if (!cfg80211_combine_bsses(dev, new)) {
 806                                 kfree(new);
 807                                 goto drop;
 808                         }
 809                 }
 810
 811                 list_add_tail(&new->list, &dev->bss_list);
 812                 rb_insert_bss(dev, new);
 813                 found = new;
 814         }
 815
 816         dev->bss_generation++;
 817         bss_ref_get(dev, found);
 818         spin_unlock_bh(&dev->bss_lock);
 819
 820         return found;
 821  drop:
 822         spin_unlock_bh(&dev->bss_lock);
 823         return NULL;
 824 }
 825
 826 static struct ieee80211_channel *
 827 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
 828                          struct ieee80211_channel *channel)
 829 {
 830         const u8 *tmp;
 831         u32 freq;
 832         int channel_number = -1;
 833
 834         tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen);
 835         if (tmp && tmp[1] == 1) {
 836                 channel_number = tmp[2];
 837         } else {
 838                 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen);
 839                 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) {
 840                         struct ieee80211_ht_operation *htop = (void *)(tmp + 2);
 841
 842                         channel_number = htop->primary_chan;
 843                 }
 844         }
 845
 846         if (channel_number < 0)
 847                 return channel;
 848
 849         freq = ieee80211_channel_to_frequency(channel_number, channel->band);
 850         channel = ieee80211_get_channel(wiphy, freq);
 851         if (!channel)
 852                 return NULL;
 853         if (channel->flags & IEEE80211_CHAN_DISABLED)
 854                 return NULL;
 855         return channel;
 856 }
 857
 858 struct cfg80211_bss*
 859 cfg80211_inform_bss(struct wiphy *wiphy,
 860                     struct ieee80211_channel *channel,
 861                     const u8 *bssid, u64 tsf, u16 capability,
 862                     u16 beacon_interval, const u8 *ie, size_t ielen,
 863                     s32 signal, gfp_t gfp)
 864 {
 865         struct cfg80211_bss_ies *ies;
 866         struct cfg80211_internal_bss tmp = {}, *res;
 867
 868         if (WARN_ON(!wiphy))
 869                 return NULL;
 870
 871         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
 872                         (signal < 0 || signal > 100)))
 873                 return NULL;
 874
 875         channel = cfg80211_get_bss_channel(wiphy, ie, ielen, channel);
 876         if (!channel)
 877                 return NULL;
 878
 879         memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
 880         tmp.pub.channel = channel;
 881         tmp.pub.signal = signal;
 882         tmp.pub.beacon_interval = beacon_interval;
 883         tmp.pub.capability = capability;
 884         /*
 885          * Since we do not know here whether the IEs are from a Beacon or Probe
 886          * Response frame, we need to pick one of the options and only use it
 887          * with the driver that does not provide the full Beacon/Probe Response
 888          * frame. Use Beacon frame pointer to avoid indicating that this should
 889          * override the IEs pointer should we have received an earlier
 890          * indication of Probe Response data.
 891          */
 892         ies = kmalloc(sizeof(*ies) + ielen, gfp);
 893         if (!ies)
 894                 return NULL;
 895         ies->len = ielen;
 896         ies->tsf = tsf;
 897         memcpy(ies->data, ie, ielen);
 898
 899         rcu_assign_pointer(tmp.pub.beacon_ies, ies);
 900         rcu_assign_pointer(tmp.pub.ies, ies);
 901
 902         res = cfg80211_bss_update(wiphy_to_dev(wiphy), &tmp);
 903         if (!res)
 904                 return NULL;
 905
 906         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 907                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 908
 909         trace_cfg80211_return_bss(&res->pub);
 910         /* cfg80211_bss_update gives us a referenced result */
 911         return &res->pub;
 912 }
 913 EXPORT_SYMBOL(cfg80211_inform_bss);
 914
 915 struct cfg80211_bss *
 916 cfg80211_inform_bss_frame(struct wiphy *wiphy,
 917                           struct ieee80211_channel *channel,
 918                           struct ieee80211_mgmt *mgmt, size_t len,
 919                           s32 signal, gfp_t gfp)
 920 {
 921         struct cfg80211_internal_bss tmp = {}, *res;
 922         struct cfg80211_bss_ies *ies;
 923         size_t ielen = len - offsetof(struct ieee80211_mgmt,
 924                                       u.probe_resp.variable);
 925
 926         BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
 927                         offsetof(struct ieee80211_mgmt, u.beacon.variable));
 928
 929         trace_cfg80211_inform_bss_frame(wiphy, channel, mgmt, len, signal);
 930
 931         if (WARN_ON(!mgmt))
 932                 return NULL;
 933
 934         if (WARN_ON(!wiphy))
 935                 return NULL;
 936
 937         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
 938                     (signal < 0 || signal > 100)))
 939                 return NULL;
 940
 941         if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
 942                 return NULL;
 943
 944         channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable,
 945                                            ielen, channel);
 946         if (!channel)
 947                 return NULL;
 948
 949         ies = kmalloc(sizeof(*ies) + ielen, gfp);
 950         if (!ies)
 951                 return NULL;
 952         ies->len = ielen;
 953         ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
 954         memcpy(ies->data, mgmt->u.probe_resp.variable, ielen);
 955
 956         if (ieee80211_is_probe_resp(mgmt->frame_control))
 957                 rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
 958         else
 959                 rcu_assign_pointer(tmp.pub.beacon_ies, ies);
 960         rcu_assign_pointer(tmp.pub.ies, ies);
 961
 962         memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN);
 963         tmp.pub.channel = channel;
 964         tmp.pub.signal = signal;
 965         tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
 966         tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
 967
 968         res = cfg80211_bss_update(wiphy_to_dev(wiphy), &tmp);
 969         if (!res)
 970                 return NULL;
 971
 972         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 973                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 974
 975         trace_cfg80211_return_bss(&res->pub);
 976         /* cfg80211_bss_update gives us a referenced result */
 977         return &res->pub;
 978 }
 979 EXPORT_SYMBOL(cfg80211_inform_bss_frame);
 980
 981 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
 982 {
 983         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 984         struct cfg80211_internal_bss *bss;
 985
 986         if (!pub)
 987                 return;
 988
 989         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 990
 991         spin_lock_bh(&dev->bss_lock);
 992         bss_ref_get(dev, bss);
 993         spin_unlock_bh(&dev->bss_lock);
 994 }
 995 EXPORT_SYMBOL(cfg80211_ref_bss);
 996
 997 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
 998 {
 999         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
1000         struct cfg80211_internal_bss *bss;
1001
1002         if (!pub)
1003                 return;
1004
1005         bss = container_of(pub, struct cfg80211_internal_bss, pub);
1006
1007         spin_lock_bh(&dev->bss_lock);
1008         bss_ref_put(dev, bss);
1009         spin_unlock_bh(&dev->bss_lock);
1010 }
1011 EXPORT_SYMBOL(cfg80211_put_bss);
1012
1013 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
1014 {
1015         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
1016         struct cfg80211_internal_bss *bss;
1017
1018         if (WARN_ON(!pub))
1019                 return;
1020
1021         bss = container_of(pub, struct cfg80211_internal_bss, pub);
1022
1023         spin_lock_bh(&dev->bss_lock);
1024         if (!list_empty(&bss->list)) {
1025                 if (__cfg80211_unlink_bss(dev, bss))
1026                         dev->bss_generation++;
1027         }
1028         spin_unlock_bh(&dev->bss_lock);
1029 }
1030 EXPORT_SYMBOL(cfg80211_unlink_bss);
1031
1032 #ifdef CONFIG_CFG80211_WEXT
1033 int cfg80211_wext_siwscan(struct net_device *dev,
1034                           struct iw_request_info *info,
1035                           union iwreq_data *wrqu, char *extra)
1036 {
1037         struct cfg80211_registered_device *rdev;
1038         struct wiphy *wiphy;
1039         struct iw_scan_req *wreq = NULL;
1040         struct cfg80211_scan_request *creq = NULL;
1041         int i, err, n_channels = 0;
1042         enum ieee80211_band band;
1043
1044         if (!netif_running(dev))
1045                 return -ENETDOWN;
1046
1047         if (wrqu->data.length == sizeof(struct iw_scan_req))
1048                 wreq = (struct iw_scan_req *)extra;
1049
1050         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1051
1052         if (IS_ERR(rdev))
1053                 return PTR_ERR(rdev);
1054
1055         if (rdev->scan_req) {
1056                 err = -EBUSY;
1057                 goto out;
1058         }
1059
1060         wiphy = &rdev->wiphy;
1061
1062         /* Determine number of channels, needed to allocate creq */
1063         if (wreq && wreq->num_channels)
1064                 n_channels = wreq->num_channels;
1065         else {
1066                 for (band = 0; band < IEEE80211_NUM_BANDS; band++)
1067                         if (wiphy->bands[band])
1068                                 n_channels += wiphy->bands[band]->n_channels;
1069         }
1070
1071         creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
1072                        n_channels * sizeof(void *),
1073                        GFP_ATOMIC);
1074         if (!creq) {
1075                 err = -ENOMEM;
1076                 goto out;
1077         }
1078
1079         creq->wiphy = wiphy;
1080         creq->wdev = dev->ieee80211_ptr;
1081         /* SSIDs come after channels */
1082         creq->ssids = (void *)&creq->channels[n_channels];
1083         creq->n_channels = n_channels;
1084         creq->n_ssids = 1;
1085         creq->scan_start = jiffies;
1086
1087         /* translate "Scan on frequencies" request */
1088         i = 0;
1089         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1090                 int j;
1091
1092                 if (!wiphy->bands[band])
1093                         continue;
1094
1095                 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
1096                         /* ignore disabled channels */
1097                         if (wiphy->bands[band]->channels[j].flags &
1098                                                 IEEE80211_CHAN_DISABLED)
1099                                 continue;
1100
1101                         /* If we have a wireless request structure and the
1102                          * wireless request specifies frequencies, then search
1103                          * for the matching hardware channel.
1104                          */
1105                         if (wreq && wreq->num_channels) {
1106                                 int k;
1107                                 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
1108                                 for (k = 0; k < wreq->num_channels; k++) {
1109                                         int wext_freq = cfg80211_wext_freq(wiphy, &wreq->channel_list[k]);
1110                                         if (wext_freq == wiphy_freq)
1111                                                 goto wext_freq_found;
1112                                 }
1113                                 goto wext_freq_not_found;
1114                         }
1115
1116                 wext_freq_found:
1117                         creq->channels[i] = &wiphy->bands[band]->channels[j];
1118                         i++;
1119                 wext_freq_not_found: ;
1120                 }
1121         }
1122         /* No channels found? */
1123         if (!i) {
1124                 err = -EINVAL;
1125                 goto out;
1126         }
1127
1128         /* Set real number of channels specified in creq->channels[] */
1129         creq->n_channels = i;
1130
1131         /* translate "Scan for SSID" request */
1132         if (wreq) {
1133                 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
1134                         if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
1135                                 err = -EINVAL;
1136                                 goto out;
1137                         }
1138                         memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
1139                         creq->ssids[0].ssid_len = wreq->essid_len;
1140                 }
1141                 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
1142                         creq->n_ssids = 0;
1143         }
1144
1145         for (i = 0; i < IEEE80211_NUM_BANDS; i++)
1146                 if (wiphy->bands[i])
1147                         creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
1148
1149         rdev->scan_req = creq;
1150         err = rdev_scan(rdev, creq);
1151         if (err) {
1152                 rdev->scan_req = NULL;
1153                 /* creq will be freed below */
1154         } else {
1155                 nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
1156                 /* creq now owned by driver */
1157                 creq = NULL;
1158                 dev_hold(dev);
1159         }
1160  out:
1161         kfree(creq);
1162         cfg80211_unlock_rdev(rdev);
1163         return err;
1164 }
1165 EXPORT_SYMBOL_GPL(cfg80211_wext_siwscan);
1166
1167 static void ieee80211_scan_add_ies(struct iw_request_info *info,
1168                                    const struct cfg80211_bss_ies *ies,
1169                                    char **current_ev, char *end_buf)
1170 {
1171         const u8 *pos, *end, *next;
1172         struct iw_event iwe;
1173
1174         if (!ies)
1175                 return;
1176
1177         /*
1178          * If needed, fragment the IEs buffer (at IE boundaries) into short
1179          * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
1180          */
1181         pos = ies->data;
1182         end = pos + ies->len;
1183
1184         while (end - pos > IW_GENERIC_IE_MAX) {
1185                 next = pos + 2 + pos[1];
1186                 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
1187                         next = next + 2 + next[1];
1188
1189                 memset(&iwe, 0, sizeof(iwe));
1190                 iwe.cmd = IWEVGENIE;
1191                 iwe.u.data.length = next - pos;
1192                 *current_ev = iwe_stream_add_point(info, *current_ev,
1193                                                    end_buf, &iwe,
1194                                                    (void *)pos);
1195
1196                 pos = next;
1197         }
1198
1199         if (end > pos) {
1200                 memset(&iwe, 0, sizeof(iwe));
1201                 iwe.cmd = IWEVGENIE;
1202                 iwe.u.data.length = end - pos;
1203                 *current_ev = iwe_stream_add_point(info, *current_ev,
1204                                                    end_buf, &iwe,
1205                                                    (void *)pos);
1206         }
1207 }
1208
1209 static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
1210 {
1211         unsigned long end = jiffies;
1212
1213         if (end >= start)
1214                 return jiffies_to_msecs(end - start);
1215
1216         return jiffies_to_msecs(end + (MAX_JIFFY_OFFSET - start) + 1);
1217 }
1218
1219 static char *
1220 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
1221               struct cfg80211_internal_bss *bss, char *current_ev,
1222               char *end_buf)
1223 {
1224         const struct cfg80211_bss_ies *ies;
1225         struct iw_event iwe;
1226         const u8 *ie;
1227         u8 *buf, *cfg, *p;
1228         int rem, i, sig;
1229         bool ismesh = false;
1230
1231         memset(&iwe, 0, sizeof(iwe));
1232         iwe.cmd = SIOCGIWAP;
1233         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
1234         memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
1235         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1236                                           IW_EV_ADDR_LEN);
1237
1238         memset(&iwe, 0, sizeof(iwe));
1239         iwe.cmd = SIOCGIWFREQ;
1240         iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
1241         iwe.u.freq.e = 0;
1242         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1243                                           IW_EV_FREQ_LEN);
1244
1245         memset(&iwe, 0, sizeof(iwe));
1246         iwe.cmd = SIOCGIWFREQ;
1247         iwe.u.freq.m = bss->pub.channel->center_freq;
1248         iwe.u.freq.e = 6;
1249         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1250                                           IW_EV_FREQ_LEN);
1251
1252         if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
1253                 memset(&iwe, 0, sizeof(iwe));
1254                 iwe.cmd = IWEVQUAL;
1255                 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
1256                                      IW_QUAL_NOISE_INVALID |
1257                                      IW_QUAL_QUAL_UPDATED;
1258                 switch (wiphy->signal_type) {
1259                 case CFG80211_SIGNAL_TYPE_MBM:
1260                         sig = bss->pub.signal / 100;
1261                         iwe.u.qual.level = sig;
1262                         iwe.u.qual.updated |= IW_QUAL_DBM;
1263                         if (sig < -110)         /* rather bad */
1264                                 sig = -110;
1265                         else if (sig > -40)     /* perfect */
1266                                 sig = -40;
1267                         /* will give a range of 0 .. 70 */
1268                         iwe.u.qual.qual = sig + 110;
1269                         break;
1270                 case CFG80211_SIGNAL_TYPE_UNSPEC:
1271                         iwe.u.qual.level = bss->pub.signal;
1272                         /* will give range 0 .. 100 */
1273                         iwe.u.qual.qual = bss->pub.signal;
1274                         break;
1275                 default:
1276                         /* not reached */
1277                         break;
1278                 }
1279                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1280                                                   &iwe, IW_EV_QUAL_LEN);
1281         }
1282
1283         memset(&iwe, 0, sizeof(iwe));
1284         iwe.cmd = SIOCGIWENCODE;
1285         if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
1286                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
1287         else
1288                 iwe.u.data.flags = IW_ENCODE_DISABLED;
1289         iwe.u.data.length = 0;
1290         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1291                                           &iwe, "");
1292
1293         rcu_read_lock();
1294         ies = rcu_dereference(bss->pub.ies);
1295         rem = ies->len;
1296         ie = ies->data;
1297
1298         while (rem >= 2) {
1299                 /* invalid data */
1300                 if (ie[1] > rem - 2)
1301                         break;
1302
1303                 switch (ie[0]) {
1304                 case WLAN_EID_SSID:
1305                         memset(&iwe, 0, sizeof(iwe));
1306                         iwe.cmd = SIOCGIWESSID;
1307                         iwe.u.data.length = ie[1];
1308                         iwe.u.data.flags = 1;
1309                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1310                                                           &iwe, (u8 *)ie + 2);
1311                         break;
1312                 case WLAN_EID_MESH_ID:
1313                         memset(&iwe, 0, sizeof(iwe));
1314                         iwe.cmd = SIOCGIWESSID;
1315                         iwe.u.data.length = ie[1];
1316                         iwe.u.data.flags = 1;
1317                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1318                                                           &iwe, (u8 *)ie + 2);
1319                         break;
1320                 case WLAN_EID_MESH_CONFIG:
1321                         ismesh = true;
1322                         if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
1323                                 break;
1324                         buf = kmalloc(50, GFP_ATOMIC);
1325                         if (!buf)
1326                                 break;
1327                         cfg = (u8 *)ie + 2;
1328                         memset(&iwe, 0, sizeof(iwe));
1329                         iwe.cmd = IWEVCUSTOM;
1330                         sprintf(buf, "Mesh Network Path Selection Protocol ID: "
1331                                 "0x%02X", cfg[0]);
1332                         iwe.u.data.length = strlen(buf);
1333                         current_ev = iwe_stream_add_point(info, current_ev,
1334                                                           end_buf,
1335                                                           &iwe, buf);
1336                         sprintf(buf, "Path Selection Metric ID: 0x%02X",
1337                                 cfg[1]);
1338                         iwe.u.data.length = strlen(buf);
1339                         current_ev = iwe_stream_add_point(info, current_ev,
1340                                                           end_buf,
1341                                                           &iwe, buf);
1342                         sprintf(buf, "Congestion Control Mode ID: 0x%02X",
1343                                 cfg[2]);
1344                         iwe.u.data.length = strlen(buf);
1345                         current_ev = iwe_stream_add_point(info, current_ev,
1346                                                           end_buf,
1347                                                           &iwe, buf);
1348                         sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
1349                         iwe.u.data.length = strlen(buf);
1350                         current_ev = iwe_stream_add_point(info, current_ev,
1351                                                           end_buf,
1352                                                           &iwe, buf);
1353                         sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
1354                         iwe.u.data.length = strlen(buf);
1355                         current_ev = iwe_stream_add_point(info, current_ev,
1356                                                           end_buf,
1357                                                           &iwe, buf);
1358                         sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
1359                         iwe.u.data.length = strlen(buf);
1360                         current_ev = iwe_stream_add_point(info, current_ev,
1361                                                           end_buf,
1362                                                           &iwe, buf);
1363                         sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
1364                         iwe.u.data.length = strlen(buf);
1365                         current_ev = iwe_stream_add_point(info, current_ev,
1366                                                           end_buf,
1367                                                           &iwe, buf);
1368                         kfree(buf);
1369                         break;
1370                 case WLAN_EID_SUPP_RATES:
1371                 case WLAN_EID_EXT_SUPP_RATES:
1372                         /* display all supported rates in readable format */
1373                         p = current_ev + iwe_stream_lcp_len(info);
1374
1375                         memset(&iwe, 0, sizeof(iwe));
1376                         iwe.cmd = SIOCGIWRATE;
1377                         /* Those two flags are ignored... */
1378                         iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
1379
1380                         for (i = 0; i < ie[1]; i++) {
1381                                 iwe.u.bitrate.value =
1382                                         ((ie[i + 2] & 0x7f) * 500000);
1383                                 p = iwe_stream_add_value(info, current_ev, p,
1384                                                 end_buf, &iwe, IW_EV_PARAM_LEN);
1385                         }
1386                         current_ev = p;
1387                         break;
1388                 }
1389                 rem -= ie[1] + 2;
1390                 ie += ie[1] + 2;
1391         }
1392
1393         if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
1394             ismesh) {
1395                 memset(&iwe, 0, sizeof(iwe));
1396                 iwe.cmd = SIOCGIWMODE;
1397                 if (ismesh)
1398                         iwe.u.mode = IW_MODE_MESH;
1399                 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
1400                         iwe.u.mode = IW_MODE_MASTER;
1401                 else
1402                         iwe.u.mode = IW_MODE_ADHOC;
1403                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1404                                                   &iwe, IW_EV_UINT_LEN);
1405         }
1406
1407         buf = kmalloc(30, GFP_ATOMIC);
1408         if (buf) {
1409                 memset(&iwe, 0, sizeof(iwe));
1410                 iwe.cmd = IWEVCUSTOM;
1411                 sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
1412                 iwe.u.data.length = strlen(buf);
1413                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1414                                                   &iwe, buf);
1415                 memset(&iwe, 0, sizeof(iwe));
1416                 iwe.cmd = IWEVCUSTOM;
1417                 sprintf(buf, " Last beacon: %ums ago",
1418                         elapsed_jiffies_msecs(bss->ts));
1419                 iwe.u.data.length = strlen(buf);
1420                 current_ev = iwe_stream_add_point(info, current_ev,
1421                                                   end_buf, &iwe, buf);
1422                 kfree(buf);
1423         }
1424
1425         ieee80211_scan_add_ies(info, ies, &current_ev, end_buf);
1426         rcu_read_unlock();
1427
1428         return current_ev;
1429 }
1430
1431
1432 static int ieee80211_scan_results(struct cfg80211_registered_device *dev,
1433                                   struct iw_request_info *info,
1434                                   char *buf, size_t len)
1435 {
1436         char *current_ev = buf;
1437         char *end_buf = buf + len;
1438         struct cfg80211_internal_bss *bss;
1439
1440         spin_lock_bh(&dev->bss_lock);
1441         cfg80211_bss_expire(dev);
1442
1443         list_for_each_entry(bss, &dev->bss_list, list) {
1444                 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
1445                         spin_unlock_bh(&dev->bss_lock);
1446                         return -E2BIG;
1447                 }
1448                 current_ev = ieee80211_bss(&dev->wiphy, info, bss,
1449                                            current_ev, end_buf);
1450         }
1451         spin_unlock_bh(&dev->bss_lock);
1452         return current_ev - buf;
1453 }
1454
1455
1456 int cfg80211_wext_giwscan(struct net_device *dev,
1457                           struct iw_request_info *info,
1458                           struct iw_point *data, char *extra)
1459 {
1460         struct cfg80211_registered_device *rdev;
1461         int res;
1462
1463         if (!netif_running(dev))
1464                 return -ENETDOWN;
1465
1466         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1467
1468         if (IS_ERR(rdev))
1469                 return PTR_ERR(rdev);
1470
1471         if (rdev->scan_req) {
1472                 res = -EAGAIN;
1473                 goto out;
1474         }
1475
1476         res = ieee80211_scan_results(rdev, info, extra, data->length);
1477         data->length = 0;
1478         if (res >= 0) {
1479                 data->length = res;
1480                 res = 0;
1481         }
1482
1483  out:
1484         cfg80211_unlock_rdev(rdev);
1485         return res;
1486 }
1487 EXPORT_SYMBOL_GPL(cfg80211_wext_giwscan);
1488 #endif