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 #define IEEE80211_SCAN_RESULT_EXPIRE    (30 * HZ)
  23
  24 static void bss_release(struct kref *ref)
  25 {
  26         struct cfg80211_internal_bss *bss;
  27
  28         bss = container_of(ref, struct cfg80211_internal_bss, ref);
  29
  30         if (WARN_ON(atomic_read(&bss->hold)))
  31                 return;
  32
  33         if (bss->pub.free_priv)
  34                 bss->pub.free_priv(&bss->pub);
  35
  36         if (bss->beacon_ies_allocated)
  37                 kfree(bss->pub.beacon_ies);
  38         if (bss->proberesp_ies_allocated)
  39                 kfree(bss->pub.proberesp_ies);
  40
  41         kfree(bss);
  42 }
  43
  44 /* must hold dev->bss_lock! */
  45 static void __cfg80211_unlink_bss(struct cfg80211_registered_device *dev,
  46                                   struct cfg80211_internal_bss *bss)
  47 {
  48         list_del_init(&bss->list);
  49         rb_erase(&bss->rbn, &dev->bss_tree);
  50         kref_put(&bss->ref, bss_release);
  51 }
  52
  53 /* must hold dev->bss_lock! */
  54 static void __cfg80211_bss_expire(struct cfg80211_registered_device *dev,
  55                                   unsigned long expire_time)
  56 {
  57         struct cfg80211_internal_bss *bss, *tmp;
  58         bool expired = false;
  59
  60         list_for_each_entry_safe(bss, tmp, &dev->bss_list, list) {
  61                 if (atomic_read(&bss->hold))
  62                         continue;
  63                 if (!time_after(expire_time, bss->ts))
  64                         continue;
  65
  66                 __cfg80211_unlink_bss(dev, bss);
  67                 expired = true;
  68         }
  69
  70         if (expired)
  71                 dev->bss_generation++;
  72 }
  73
  74 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev, bool leak)
  75 {
  76         struct cfg80211_scan_request *request;
  77         struct wireless_dev *wdev;
  78 #ifdef CONFIG_CFG80211_WEXT
  79         union iwreq_data wrqu;
  80 #endif
  81
  82         ASSERT_RDEV_LOCK(rdev);
  83
  84         request = rdev->scan_req;
  85
  86         if (!request)
  87                 return;
  88
  89         wdev = request->wdev;
  90
  91         /*
  92          * This must be before sending the other events!
  93          * Otherwise, wpa_supplicant gets completely confused with
  94          * wext events.
  95          */
  96         if (wdev->netdev)
  97                 cfg80211_sme_scan_done(wdev->netdev);
  98
  99         if (request->aborted) {
 100                 nl80211_send_scan_aborted(rdev, wdev);
 101         } else {
 102                 if (request->flags & NL80211_SCAN_FLAG_FLUSH) {
 103                         /* flush entries from previous scans */
 104                         spin_lock_bh(&rdev->bss_lock);
 105                         __cfg80211_bss_expire(rdev, request->scan_start);
 106                         spin_unlock_bh(&rdev->bss_lock);
 107                 }
 108                 nl80211_send_scan_done(rdev, wdev);
 109         }
 110
 111 #ifdef CONFIG_CFG80211_WEXT
 112         if (wdev->netdev && !request->aborted) {
 113                 memset(&wrqu, 0, sizeof(wrqu));
 114
 115                 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
 116         }
 117 #endif
 118
 119         if (wdev->netdev)
 120                 dev_put(wdev->netdev);
 121
 122         rdev->scan_req = NULL;
 123
 124         /*
 125          * OK. If this is invoked with "leak" then we can't
 126          * free this ... but we've cleaned it up anyway. The
 127          * driver failed to call the scan_done callback, so
 128          * all bets are off, it might still be trying to use
 129          * the scan request or not ... if it accesses the dev
 130          * in there (it shouldn't anyway) then it may crash.
 131          */
 132         if (!leak)
 133                 kfree(request);
 134 }
 135
 136 void __cfg80211_scan_done(struct work_struct *wk)
 137 {
 138         struct cfg80211_registered_device *rdev;
 139
 140         rdev = container_of(wk, struct cfg80211_registered_device,
 141                             scan_done_wk);
 142
 143         cfg80211_lock_rdev(rdev);
 144         ___cfg80211_scan_done(rdev, false);
 145         cfg80211_unlock_rdev(rdev);
 146 }
 147
 148 void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
 149 {
 150         trace_cfg80211_scan_done(request, aborted);
 151         WARN_ON(request != wiphy_to_dev(request->wiphy)->scan_req);
 152
 153         request->aborted = aborted;
 154         queue_work(cfg80211_wq, &wiphy_to_dev(request->wiphy)->scan_done_wk);
 155 }
 156 EXPORT_SYMBOL(cfg80211_scan_done);
 157
 158 void __cfg80211_sched_scan_results(struct work_struct *wk)
 159 {
 160         struct cfg80211_registered_device *rdev;
 161         struct cfg80211_sched_scan_request *request;
 162
 163         rdev = container_of(wk, struct cfg80211_registered_device,
 164                             sched_scan_results_wk);
 165
 166         request = rdev->sched_scan_req;
 167
 168         mutex_lock(&rdev->sched_scan_mtx);
 169
 170         /* we don't have sched_scan_req anymore if the scan is stopping */
 171         if (request) {
 172                 if (request->flags & NL80211_SCAN_FLAG_FLUSH) {
 173                         /* flush entries from previous scans */
 174                         spin_lock_bh(&rdev->bss_lock);
 175                         __cfg80211_bss_expire(rdev, request->scan_start);
 176                         spin_unlock_bh(&rdev->bss_lock);
 177                         request->scan_start =
 178                                 jiffies + msecs_to_jiffies(request->interval);
 179                 }
 180                 nl80211_send_sched_scan_results(rdev, request->dev);
 181         }
 182
 183         mutex_unlock(&rdev->sched_scan_mtx);
 184 }
 185
 186 void cfg80211_sched_scan_results(struct wiphy *wiphy)
 187 {
 188         trace_cfg80211_sched_scan_results(wiphy);
 189         /* ignore if we're not scanning */
 190         if (wiphy_to_dev(wiphy)->sched_scan_req)
 191                 queue_work(cfg80211_wq,
 192                            &wiphy_to_dev(wiphy)->sched_scan_results_wk);
 193 }
 194 EXPORT_SYMBOL(cfg80211_sched_scan_results);
 195
 196 void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
 197 {
 198         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
 199
 200         trace_cfg80211_sched_scan_stopped(wiphy);
 201
 202         mutex_lock(&rdev->sched_scan_mtx);
 203         __cfg80211_stop_sched_scan(rdev, true);
 204         mutex_unlock(&rdev->sched_scan_mtx);
 205 }
 206 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
 207
 208 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
 209                                bool driver_initiated)
 210 {
 211         struct net_device *dev;
 212
 213         lockdep_assert_held(&rdev->sched_scan_mtx);
 214
 215         if (!rdev->sched_scan_req)
 216                 return -ENOENT;
 217
 218         dev = rdev->sched_scan_req->dev;
 219
 220         if (!driver_initiated) {
 221                 int err = rdev_sched_scan_stop(rdev, dev);
 222                 if (err)
 223                         return err;
 224         }
 225
 226         nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED);
 227
 228         kfree(rdev->sched_scan_req);
 229         rdev->sched_scan_req = NULL;
 230
 231         return 0;
 232 }
 233
 234 /* must hold dev->bss_lock! */
 235 void cfg80211_bss_age(struct cfg80211_registered_device *dev,
 236                       unsigned long age_secs)
 237 {
 238         struct cfg80211_internal_bss *bss;
 239         unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
 240
 241         list_for_each_entry(bss, &dev->bss_list, list)
 242                 bss->ts -= age_jiffies;
 243 }
 244
 245 void cfg80211_bss_expire(struct cfg80211_registered_device *dev)
 246 {
 247         __cfg80211_bss_expire(dev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
 248 }
 249
 250 const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len)
 251 {
 252         while (len > 2 && ies[0] != eid) {
 253                 len -= ies[1] + 2;
 254                 ies += ies[1] + 2;
 255         }
 256         if (len < 2)
 257                 return NULL;
 258         if (len < 2 + ies[1])
 259                 return NULL;
 260         return ies;
 261 }
 262 EXPORT_SYMBOL(cfg80211_find_ie);
 263
 264 const u8 *cfg80211_find_vendor_ie(unsigned int oui, u8 oui_type,
 265                                   const u8 *ies, int len)
 266 {
 267         struct ieee80211_vendor_ie *ie;
 268         const u8 *pos = ies, *end = ies + len;
 269         int ie_oui;
 270
 271         while (pos < end) {
 272                 pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos,
 273                                        end - pos);
 274                 if (!pos)
 275                         return NULL;
 276
 277                 if (end - pos < sizeof(*ie))
 278                         return NULL;
 279
 280                 ie = (struct ieee80211_vendor_ie *)pos;
 281                 ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2];
 282                 if (ie_oui == oui && ie->oui_type == oui_type)
 283                         return pos;
 284
 285                 pos += 2 + ie->len;
 286         }
 287         return NULL;
 288 }
 289 EXPORT_SYMBOL(cfg80211_find_vendor_ie);
 290
 291 static int cmp_ies(u8 num, u8 *ies1, size_t len1, u8 *ies2, size_t len2)
 292 {
 293         const u8 *ie1 = cfg80211_find_ie(num, ies1, len1);
 294         const u8 *ie2 = cfg80211_find_ie(num, ies2, len2);
 295
 296         /* equal if both missing */
 297         if (!ie1 && !ie2)
 298                 return 0;
 299         /* sort missing IE before (left of) present IE */
 300         if (!ie1)
 301                 return -1;
 302         if (!ie2)
 303                 return 1;
 304
 305         /* sort by length first, then by contents */
 306         if (ie1[1] != ie2[1])
 307                 return ie2[1] - ie1[1];
 308         return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
 309 }
 310
 311 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
 312                    const u8 *ssid, size_t ssid_len)
 313 {
 314         const u8 *ssidie;
 315
 316         if (bssid && !ether_addr_equal(a->bssid, bssid))
 317                 return false;
 318
 319         if (!ssid)
 320                 return true;
 321
 322         ssidie = cfg80211_find_ie(WLAN_EID_SSID,
 323                                   a->information_elements,
 324                                   a->len_information_elements);
 325         if (!ssidie)
 326                 return false;
 327         if (ssidie[1] != ssid_len)
 328                 return false;
 329         return memcmp(ssidie + 2, ssid, ssid_len) == 0;
 330 }
 331
 332 static bool is_mesh_bss(struct cfg80211_bss *a)
 333 {
 334         const u8 *ie;
 335
 336         if (!WLAN_CAPABILITY_IS_STA_BSS(a->capability))
 337                 return false;
 338
 339         ie = cfg80211_find_ie(WLAN_EID_MESH_ID,
 340                               a->information_elements,
 341                               a->len_information_elements);
 342         if (!ie)
 343                 return false;
 344
 345         ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
 346                               a->information_elements,
 347                               a->len_information_elements);
 348         if (!ie)
 349                 return false;
 350
 351         return true;
 352 }
 353
 354 static bool is_mesh(struct cfg80211_bss *a,
 355                     const u8 *meshid, size_t meshidlen,
 356                     const u8 *meshcfg)
 357 {
 358         const u8 *ie;
 359
 360         if (!WLAN_CAPABILITY_IS_STA_BSS(a->capability))
 361                 return false;
 362
 363         ie = cfg80211_find_ie(WLAN_EID_MESH_ID,
 364                               a->information_elements,
 365                               a->len_information_elements);
 366         if (!ie)
 367                 return false;
 368         if (ie[1] != meshidlen)
 369                 return false;
 370         if (memcmp(ie + 2, meshid, meshidlen))
 371                 return false;
 372
 373         ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
 374                               a->information_elements,
 375                               a->len_information_elements);
 376         if (!ie)
 377                 return false;
 378         if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
 379                 return false;
 380
 381         /*
 382          * Ignore mesh capability (last two bytes of the IE) when
 383          * comparing since that may differ between stations taking
 384          * part in the same mesh.
 385          */
 386         return memcmp(ie + 2, meshcfg,
 387                       sizeof(struct ieee80211_meshconf_ie) - 2) == 0;
 388 }
 389
 390 static int cmp_bss_core(struct cfg80211_bss *a, struct cfg80211_bss *b)
 391 {
 392         int r;
 393
 394         if (a->channel != b->channel)
 395                 return b->channel->center_freq - a->channel->center_freq;
 396
 397         if (is_mesh_bss(a) && is_mesh_bss(b)) {
 398                 r = cmp_ies(WLAN_EID_MESH_ID,
 399                             a->information_elements,
 400                             a->len_information_elements,
 401                             b->information_elements,
 402                             b->len_information_elements);
 403                 if (r)
 404                         return r;
 405                 return cmp_ies(WLAN_EID_MESH_CONFIG,
 406                                a->information_elements,
 407                                a->len_information_elements,
 408                                b->information_elements,
 409                                b->len_information_elements);
 410         }
 411
 412         /*
 413          * we can't use compare_ether_addr here since we need a < > operator.
 414          * The binary return value of compare_ether_addr isn't enough
 415          */
 416         return memcmp(a->bssid, b->bssid, sizeof(a->bssid));
 417 }
 418
 419 static int cmp_bss(struct cfg80211_bss *a,
 420                    struct cfg80211_bss *b)
 421 {
 422         int r;
 423
 424         r = cmp_bss_core(a, b);
 425         if (r)
 426                 return r;
 427
 428         return cmp_ies(WLAN_EID_SSID,
 429                        a->information_elements,
 430                        a->len_information_elements,
 431                        b->information_elements,
 432                        b->len_information_elements);
 433 }
 434
 435 static int cmp_hidden_bss(struct cfg80211_bss *a, struct cfg80211_bss *b)
 436 {
 437         const u8 *ie1;
 438         const u8 *ie2;
 439         int i;
 440         int r;
 441
 442         r = cmp_bss_core(a, b);
 443         if (r)
 444                 return r;
 445
 446         ie1 = cfg80211_find_ie(WLAN_EID_SSID,
 447                                a->information_elements,
 448                                a->len_information_elements);
 449         ie2 = cfg80211_find_ie(WLAN_EID_SSID,
 450                                b->information_elements,
 451                                b->len_information_elements);
 452
 453         /*
 454          * Key comparator must use same algorithm in any rb-tree
 455          * search function (order is important), otherwise ordering
 456          * of items in the tree is broken and search gives incorrect
 457          * results. This code uses same order as cmp_ies() does.
 458          *
 459          * Note that due to the differring behaviour with hidden SSIDs
 460          * this function only works when "b" is the tree element and
 461          * "a" is the key we're looking for.
 462          */
 463
 464         /* sort missing IE before (left of) present IE */
 465         if (!ie1)
 466                 return -1;
 467         if (!ie2)
 468                 return 1;
 469
 470         /* zero-size SSID is used as an indication of the hidden bss */
 471         if (!ie2[1])
 472                 return 0;
 473
 474         /* sort by length first, then by contents */
 475         if (ie1[1] != ie2[1])
 476                 return ie2[1] - ie1[1];
 477
 478         /*
 479          * zeroed SSID ie is another indication of a hidden bss;
 480          * if it isn't zeroed just return the regular sort value
 481          * to find the next candidate
 482          */
 483         for (i = 0; i < ie2[1]; i++)
 484                 if (ie2[i + 2])
 485                         return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
 486
 487         return 0;
 488 }
 489
 490 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
 491                                       struct ieee80211_channel *channel,
 492                                       const u8 *bssid,
 493                                       const u8 *ssid, size_t ssid_len,
 494                                       u16 capa_mask, u16 capa_val)
 495 {
 496         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 497         struct cfg80211_internal_bss *bss, *res = NULL;
 498         unsigned long now = jiffies;
 499
 500         trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, capa_mask,
 501                                capa_val);
 502
 503         spin_lock_bh(&dev->bss_lock);
 504
 505         list_for_each_entry(bss, &dev->bss_list, list) {
 506                 if ((bss->pub.capability & capa_mask) != capa_val)
 507                         continue;
 508                 if (channel && bss->pub.channel != channel)
 509                         continue;
 510                 /* Don't get expired BSS structs */
 511                 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
 512                     !atomic_read(&bss->hold))
 513                         continue;
 514                 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
 515                         res = bss;
 516                         kref_get(&res->ref);
 517                         break;
 518                 }
 519         }
 520
 521         spin_unlock_bh(&dev->bss_lock);
 522         if (!res)
 523                 return NULL;
 524         trace_cfg80211_return_bss(&res->pub);
 525         return &res->pub;
 526 }
 527 EXPORT_SYMBOL(cfg80211_get_bss);
 528
 529 struct cfg80211_bss *cfg80211_get_mesh(struct wiphy *wiphy,
 530                                        struct ieee80211_channel *channel,
 531                                        const u8 *meshid, size_t meshidlen,
 532                                        const u8 *meshcfg)
 533 {
 534         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 535         struct cfg80211_internal_bss *bss, *res = NULL;
 536
 537         spin_lock_bh(&dev->bss_lock);
 538
 539         list_for_each_entry(bss, &dev->bss_list, list) {
 540                 if (channel && bss->pub.channel != channel)
 541                         continue;
 542                 if (is_mesh(&bss->pub, meshid, meshidlen, meshcfg)) {
 543                         res = bss;
 544                         kref_get(&res->ref);
 545                         break;
 546                 }
 547         }
 548
 549         spin_unlock_bh(&dev->bss_lock);
 550         if (!res)
 551                 return NULL;
 552         return &res->pub;
 553 }
 554 EXPORT_SYMBOL(cfg80211_get_mesh);
 555
 556
 557 static void rb_insert_bss(struct cfg80211_registered_device *dev,
 558                           struct cfg80211_internal_bss *bss)
 559 {
 560         struct rb_node **p = &dev->bss_tree.rb_node;
 561         struct rb_node *parent = NULL;
 562         struct cfg80211_internal_bss *tbss;
 563         int cmp;
 564
 565         while (*p) {
 566                 parent = *p;
 567                 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
 568
 569                 cmp = cmp_bss(&bss->pub, &tbss->pub);
 570
 571                 if (WARN_ON(!cmp)) {
 572                         /* will sort of leak this BSS */
 573                         return;
 574                 }
 575
 576                 if (cmp < 0)
 577                         p = &(*p)->rb_left;
 578                 else
 579                         p = &(*p)->rb_right;
 580         }
 581
 582         rb_link_node(&bss->rbn, parent, p);
 583         rb_insert_color(&bss->rbn, &dev->bss_tree);
 584 }
 585
 586 static struct cfg80211_internal_bss *
 587 rb_find_bss(struct cfg80211_registered_device *dev,
 588             struct cfg80211_internal_bss *res)
 589 {
 590         struct rb_node *n = dev->bss_tree.rb_node;
 591         struct cfg80211_internal_bss *bss;
 592         int r;
 593
 594         while (n) {
 595                 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
 596                 r = cmp_bss(&res->pub, &bss->pub);
 597
 598                 if (r == 0)
 599                         return bss;
 600                 else if (r < 0)
 601                         n = n->rb_left;
 602                 else
 603                         n = n->rb_right;
 604         }
 605
 606         return NULL;
 607 }
 608
 609 static struct cfg80211_internal_bss *
 610 rb_find_hidden_bss(struct cfg80211_registered_device *dev,
 611                    struct cfg80211_internal_bss *res)
 612 {
 613         struct rb_node *n = dev->bss_tree.rb_node;
 614         struct cfg80211_internal_bss *bss;
 615         int r;
 616
 617         while (n) {
 618                 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
 619                 r = cmp_hidden_bss(&res->pub, &bss->pub);
 620
 621                 if (r == 0)
 622                         return bss;
 623                 else if (r < 0)
 624                         n = n->rb_left;
 625                 else
 626                         n = n->rb_right;
 627         }
 628
 629         return NULL;
 630 }
 631
 632 static void
 633 copy_hidden_ies(struct cfg80211_internal_bss *res,
 634                 struct cfg80211_internal_bss *hidden)
 635 {
 636         if (unlikely(res->pub.beacon_ies))
 637                 return;
 638         if (WARN_ON(!hidden->pub.beacon_ies))
 639                 return;
 640
 641         res->pub.beacon_ies = kmalloc(hidden->pub.len_beacon_ies, GFP_ATOMIC);
 642         if (unlikely(!res->pub.beacon_ies))
 643                 return;
 644
 645         res->beacon_ies_allocated = true;
 646         res->pub.len_beacon_ies = hidden->pub.len_beacon_ies;
 647         memcpy(res->pub.beacon_ies, hidden->pub.beacon_ies,
 648                res->pub.len_beacon_ies);
 649 }
 650
 651 static struct cfg80211_internal_bss *
 652 cfg80211_bss_update(struct cfg80211_registered_device *dev,
 653                     struct cfg80211_internal_bss *res)
 654 {
 655         struct cfg80211_internal_bss *found = NULL;
 656
 657         /*
 658          * The reference to "res" is donated to this function.
 659          */
 660
 661         if (WARN_ON(!res->pub.channel)) {
 662                 kref_put(&res->ref, bss_release);
 663                 return NULL;
 664         }
 665
 666         res->ts = jiffies;
 667
 668         spin_lock_bh(&dev->bss_lock);
 669
 670         found = rb_find_bss(dev, res);
 671
 672         if (found) {
 673                 found->pub.beacon_interval = res->pub.beacon_interval;
 674                 found->pub.tsf = res->pub.tsf;
 675                 found->pub.signal = res->pub.signal;
 676                 found->pub.capability = res->pub.capability;
 677                 found->ts = res->ts;
 678
 679                 /* Update IEs */
 680                 if (res->pub.proberesp_ies) {
 681                         size_t used = dev->wiphy.bss_priv_size + sizeof(*res);
 682                         size_t ielen = res->pub.len_proberesp_ies;
 683
 684                         if (found->pub.proberesp_ies &&
 685                             !found->proberesp_ies_allocated &&
 686                             ksize(found) >= used + ielen) {
 687                                 memcpy(found->pub.proberesp_ies,
 688                                        res->pub.proberesp_ies, ielen);
 689                                 found->pub.len_proberesp_ies = ielen;
 690                         } else {
 691                                 u8 *ies = found->pub.proberesp_ies;
 692
 693                                 if (found->proberesp_ies_allocated)
 694                                         ies = krealloc(ies, ielen, GFP_ATOMIC);
 695                                 else
 696                                         ies = kmalloc(ielen, GFP_ATOMIC);
 697
 698                                 if (ies) {
 699                                         memcpy(ies, res->pub.proberesp_ies,
 700                                                ielen);
 701                                         found->proberesp_ies_allocated = true;
 702                                         found->pub.proberesp_ies = ies;
 703                                         found->pub.len_proberesp_ies = ielen;
 704                                 }
 705                         }
 706
 707                         /* Override possible earlier Beacon frame IEs */
 708                         found->pub.information_elements =
 709                                 found->pub.proberesp_ies;
 710                         found->pub.len_information_elements =
 711                                 found->pub.len_proberesp_ies;
 712                 }
 713
 714                 if (res->pub.beacon_ies) {
 715                         size_t used = dev->wiphy.bss_priv_size + sizeof(*res);
 716                         size_t ielen = res->pub.len_beacon_ies;
 717                         bool information_elements_is_beacon_ies =
 718                                 (found->pub.information_elements ==
 719                                  found->pub.beacon_ies);
 720
 721                         if (found->pub.beacon_ies &&
 722                             !found->beacon_ies_allocated &&
 723                             ksize(found) >= used + ielen) {
 724                                 memcpy(found->pub.beacon_ies,
 725                                        res->pub.beacon_ies, ielen);
 726                                 found->pub.len_beacon_ies = ielen;
 727                         } else {
 728                                 u8 *ies = found->pub.beacon_ies;
 729
 730                                 if (found->beacon_ies_allocated)
 731                                         ies = krealloc(ies, ielen, GFP_ATOMIC);
 732                                 else
 733                                         ies = kmalloc(ielen, GFP_ATOMIC);
 734
 735                                 if (ies) {
 736                                         memcpy(ies, res->pub.beacon_ies,
 737                                                ielen);
 738                                         found->beacon_ies_allocated = true;
 739                                         found->pub.beacon_ies = ies;
 740                                         found->pub.len_beacon_ies = ielen;
 741                                 }
 742                         }
 743
 744                         /* Override IEs if they were from a beacon before */
 745                         if (information_elements_is_beacon_ies) {
 746                                 found->pub.information_elements =
 747                                         found->pub.beacon_ies;
 748                                 found->pub.len_information_elements =
 749                                         found->pub.len_beacon_ies;
 750                         }
 751                 }
 752
 753                 kref_put(&res->ref, bss_release);
 754         } else {
 755                 struct cfg80211_internal_bss *hidden;
 756
 757                 /* First check if the beacon is a probe response from
 758                  * a hidden bss. If so, copy beacon ies (with nullified
 759                  * ssid) into the probe response bss entry (with real ssid).
 760                  * It is required basically for PSM implementation
 761                  * (probe responses do not contain tim ie) */
 762
 763                 /* TODO: The code is not trying to update existing probe
 764                  * response bss entries when beacon ies are
 765                  * getting changed. */
 766                 hidden = rb_find_hidden_bss(dev, res);
 767                 if (hidden)
 768                         copy_hidden_ies(res, hidden);
 769
 770                 /* this "consumes" the reference */
 771                 list_add_tail(&res->list, &dev->bss_list);
 772                 rb_insert_bss(dev, res);
 773                 found = res;
 774         }
 775
 776         dev->bss_generation++;
 777         spin_unlock_bh(&dev->bss_lock);
 778
 779         kref_get(&found->ref);
 780         return found;
 781 }
 782
 783 static struct ieee80211_channel *
 784 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
 785                          struct ieee80211_channel *channel)
 786 {
 787         const u8 *tmp;
 788         u32 freq;
 789         int channel_number = -1;
 790
 791         tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen);
 792         if (tmp && tmp[1] == 1) {
 793                 channel_number = tmp[2];
 794         } else {
 795                 tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen);
 796                 if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) {
 797                         struct ieee80211_ht_operation *htop = (void *)(tmp + 2);
 798
 799                         channel_number = htop->primary_chan;
 800                 }
 801         }
 802
 803         if (channel_number < 0)
 804                 return channel;
 805
 806         freq = ieee80211_channel_to_frequency(channel_number, channel->band);
 807         channel = ieee80211_get_channel(wiphy, freq);
 808         if (!channel)
 809                 return NULL;
 810         if (channel->flags & IEEE80211_CHAN_DISABLED)
 811                 return NULL;
 812         return channel;
 813 }
 814
 815 struct cfg80211_bss*
 816 cfg80211_inform_bss(struct wiphy *wiphy,
 817                     struct ieee80211_channel *channel,
 818                     const u8 *bssid, u64 tsf, u16 capability,
 819                     u16 beacon_interval, const u8 *ie, size_t ielen,
 820                     s32 signal, gfp_t gfp)
 821 {
 822         struct cfg80211_internal_bss *res;
 823         size_t privsz;
 824
 825         if (WARN_ON(!wiphy))
 826                 return NULL;
 827
 828         privsz = wiphy->bss_priv_size;
 829
 830         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
 831                         (signal < 0 || signal > 100)))
 832                 return NULL;
 833
 834         channel = cfg80211_get_bss_channel(wiphy, ie, ielen, channel);
 835         if (!channel)
 836                 return NULL;
 837
 838         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
 839         if (!res)
 840                 return NULL;
 841
 842         memcpy(res->pub.bssid, bssid, ETH_ALEN);
 843         res->pub.channel = channel;
 844         res->pub.signal = signal;
 845         res->pub.tsf = tsf;
 846         res->pub.beacon_interval = beacon_interval;
 847         res->pub.capability = capability;
 848         /*
 849          * Since we do not know here whether the IEs are from a Beacon or Probe
 850          * Response frame, we need to pick one of the options and only use it
 851          * with the driver that does not provide the full Beacon/Probe Response
 852          * frame. Use Beacon frame pointer to avoid indicating that this should
 853          * override the information_elements pointer should we have received an
 854          * earlier indication of Probe Response data.
 855          *
 856          * The initial buffer for the IEs is allocated with the BSS entry and
 857          * is located after the private area.
 858          */
 859         res->pub.beacon_ies = (u8 *)res + sizeof(*res) + privsz;
 860         memcpy(res->pub.beacon_ies, ie, ielen);
 861         res->pub.len_beacon_ies = ielen;
 862         res->pub.information_elements = res->pub.beacon_ies;
 863         res->pub.len_information_elements = res->pub.len_beacon_ies;
 864
 865         kref_init(&res->ref);
 866
 867         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res);
 868         if (!res)
 869                 return NULL;
 870
 871         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 872                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 873
 874         trace_cfg80211_return_bss(&res->pub);
 875         /* cfg80211_bss_update gives us a referenced result */
 876         return &res->pub;
 877 }
 878 EXPORT_SYMBOL(cfg80211_inform_bss);
 879
 880 struct cfg80211_bss *
 881 cfg80211_inform_bss_frame(struct wiphy *wiphy,
 882                           struct ieee80211_channel *channel,
 883                           struct ieee80211_mgmt *mgmt, size_t len,
 884                           s32 signal, gfp_t gfp)
 885 {
 886         struct cfg80211_internal_bss *res;
 887         size_t ielen = len - offsetof(struct ieee80211_mgmt,
 888                                       u.probe_resp.variable);
 889         size_t privsz;
 890
 891         BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
 892                         offsetof(struct ieee80211_mgmt, u.beacon.variable));
 893
 894         trace_cfg80211_inform_bss_frame(wiphy, channel, mgmt, len, signal);
 895
 896         if (WARN_ON(!mgmt))
 897                 return NULL;
 898
 899         if (WARN_ON(!wiphy))
 900                 return NULL;
 901
 902         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
 903                     (signal < 0 || signal > 100)))
 904                 return NULL;
 905
 906         if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
 907                 return NULL;
 908
 909         privsz = wiphy->bss_priv_size;
 910
 911         channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable,
 912                                            ielen, channel);
 913         if (!channel)
 914                 return NULL;
 915
 916         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
 917         if (!res)
 918                 return NULL;
 919
 920         memcpy(res->pub.bssid, mgmt->bssid, ETH_ALEN);
 921         res->pub.channel = channel;
 922         res->pub.signal = signal;
 923         res->pub.tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
 924         res->pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
 925         res->pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
 926         /*
 927          * The initial buffer for the IEs is allocated with the BSS entry and
 928          * is located after the private area.
 929          */
 930         if (ieee80211_is_probe_resp(mgmt->frame_control)) {
 931                 res->pub.proberesp_ies = (u8 *) res + sizeof(*res) + privsz;
 932                 memcpy(res->pub.proberesp_ies, mgmt->u.probe_resp.variable,
 933                        ielen);
 934                 res->pub.len_proberesp_ies = ielen;
 935                 res->pub.information_elements = res->pub.proberesp_ies;
 936                 res->pub.len_information_elements = res->pub.len_proberesp_ies;
 937         } else {
 938                 res->pub.beacon_ies = (u8 *) res + sizeof(*res) + privsz;
 939                 memcpy(res->pub.beacon_ies, mgmt->u.beacon.variable, ielen);
 940                 res->pub.len_beacon_ies = ielen;
 941                 res->pub.information_elements = res->pub.beacon_ies;
 942                 res->pub.len_information_elements = res->pub.len_beacon_ies;
 943         }
 944
 945         kref_init(&res->ref);
 946
 947         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res);
 948         if (!res)
 949                 return NULL;
 950
 951         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 952                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 953
 954         trace_cfg80211_return_bss(&res->pub);
 955         /* cfg80211_bss_update gives us a referenced result */
 956         return &res->pub;
 957 }
 958 EXPORT_SYMBOL(cfg80211_inform_bss_frame);
 959
 960 void cfg80211_ref_bss(struct cfg80211_bss *pub)
 961 {
 962         struct cfg80211_internal_bss *bss;
 963
 964         if (!pub)
 965                 return;
 966
 967         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 968         kref_get(&bss->ref);
 969 }
 970 EXPORT_SYMBOL(cfg80211_ref_bss);
 971
 972 void cfg80211_put_bss(struct cfg80211_bss *pub)
 973 {
 974         struct cfg80211_internal_bss *bss;
 975
 976         if (!pub)
 977                 return;
 978
 979         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 980         kref_put(&bss->ref, bss_release);
 981 }
 982 EXPORT_SYMBOL(cfg80211_put_bss);
 983
 984 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
 985 {
 986         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 987         struct cfg80211_internal_bss *bss;
 988
 989         if (WARN_ON(!pub))
 990                 return;
 991
 992         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 993
 994         spin_lock_bh(&dev->bss_lock);
 995         if (!list_empty(&bss->list)) {
 996                 __cfg80211_unlink_bss(dev, bss);
 997                 dev->bss_generation++;
 998         }
 999         spin_unlock_bh(&dev->bss_lock);
1000 }
1001 EXPORT_SYMBOL(cfg80211_unlink_bss);
1002
1003 #ifdef CONFIG_CFG80211_WEXT
1004 int cfg80211_wext_siwscan(struct net_device *dev,
1005                           struct iw_request_info *info,
1006                           union iwreq_data *wrqu, char *extra)
1007 {
1008         struct cfg80211_registered_device *rdev;
1009         struct wiphy *wiphy;
1010         struct iw_scan_req *wreq = NULL;
1011         struct cfg80211_scan_request *creq = NULL;
1012         int i, err, n_channels = 0;
1013         enum ieee80211_band band;
1014
1015         if (!netif_running(dev))
1016                 return -ENETDOWN;
1017
1018         if (wrqu->data.length == sizeof(struct iw_scan_req))
1019                 wreq = (struct iw_scan_req *)extra;
1020
1021         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1022
1023         if (IS_ERR(rdev))
1024                 return PTR_ERR(rdev);
1025
1026         if (rdev->scan_req) {
1027                 err = -EBUSY;
1028                 goto out;
1029         }
1030
1031         wiphy = &rdev->wiphy;
1032
1033         /* Determine number of channels, needed to allocate creq */
1034         if (wreq && wreq->num_channels)
1035                 n_channels = wreq->num_channels;
1036         else {
1037                 for (band = 0; band < IEEE80211_NUM_BANDS; band++)
1038                         if (wiphy->bands[band])
1039                                 n_channels += wiphy->bands[band]->n_channels;
1040         }
1041
1042         creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
1043                        n_channels * sizeof(void *),
1044                        GFP_ATOMIC);
1045         if (!creq) {
1046                 err = -ENOMEM;
1047                 goto out;
1048         }
1049
1050         creq->wiphy = wiphy;
1051         creq->wdev = dev->ieee80211_ptr;
1052         /* SSIDs come after channels */
1053         creq->ssids = (void *)&creq->channels[n_channels];
1054         creq->n_channels = n_channels;
1055         creq->n_ssids = 1;
1056         creq->scan_start = jiffies;
1057
1058         /* translate "Scan on frequencies" request */
1059         i = 0;
1060         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1061                 int j;
1062
1063                 if (!wiphy->bands[band])
1064                         continue;
1065
1066                 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
1067                         /* ignore disabled channels */
1068                         if (wiphy->bands[band]->channels[j].flags &
1069                                                 IEEE80211_CHAN_DISABLED)
1070                                 continue;
1071
1072                         /* If we have a wireless request structure and the
1073                          * wireless request specifies frequencies, then search
1074                          * for the matching hardware channel.
1075                          */
1076                         if (wreq && wreq->num_channels) {
1077                                 int k;
1078                                 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
1079                                 for (k = 0; k < wreq->num_channels; k++) {
1080                                         int wext_freq = cfg80211_wext_freq(wiphy, &wreq->channel_list[k]);
1081                                         if (wext_freq == wiphy_freq)
1082                                                 goto wext_freq_found;
1083                                 }
1084                                 goto wext_freq_not_found;
1085                         }
1086
1087                 wext_freq_found:
1088                         creq->channels[i] = &wiphy->bands[band]->channels[j];
1089                         i++;
1090                 wext_freq_not_found: ;
1091                 }
1092         }
1093         /* No channels found? */
1094         if (!i) {
1095                 err = -EINVAL;
1096                 goto out;
1097         }
1098
1099         /* Set real number of channels specified in creq->channels[] */
1100         creq->n_channels = i;
1101
1102         /* translate "Scan for SSID" request */
1103         if (wreq) {
1104                 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
1105                         if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
1106                                 err = -EINVAL;
1107                                 goto out;
1108                         }
1109                         memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
1110                         creq->ssids[0].ssid_len = wreq->essid_len;
1111                 }
1112                 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
1113                         creq->n_ssids = 0;
1114         }
1115
1116         for (i = 0; i < IEEE80211_NUM_BANDS; i++)
1117                 if (wiphy->bands[i])
1118                         creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
1119
1120         rdev->scan_req = creq;
1121         err = rdev_scan(rdev, creq);
1122         if (err) {
1123                 rdev->scan_req = NULL;
1124                 /* creq will be freed below */
1125         } else {
1126                 nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
1127                 /* creq now owned by driver */
1128                 creq = NULL;
1129                 dev_hold(dev);
1130         }
1131  out:
1132         kfree(creq);
1133         cfg80211_unlock_rdev(rdev);
1134         return err;
1135 }
1136 EXPORT_SYMBOL_GPL(cfg80211_wext_siwscan);
1137
1138 static void ieee80211_scan_add_ies(struct iw_request_info *info,
1139                                    struct cfg80211_bss *bss,
1140                                    char **current_ev, char *end_buf)
1141 {
1142         u8 *pos, *end, *next;
1143         struct iw_event iwe;
1144
1145         if (!bss->information_elements ||
1146             !bss->len_information_elements)
1147                 return;
1148
1149         /*
1150          * If needed, fragment the IEs buffer (at IE boundaries) into short
1151          * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
1152          */
1153         pos = bss->information_elements;
1154         end = pos + bss->len_information_elements;
1155
1156         while (end - pos > IW_GENERIC_IE_MAX) {
1157                 next = pos + 2 + pos[1];
1158                 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
1159                         next = next + 2 + next[1];
1160
1161                 memset(&iwe, 0, sizeof(iwe));
1162                 iwe.cmd = IWEVGENIE;
1163                 iwe.u.data.length = next - pos;
1164                 *current_ev = iwe_stream_add_point(info, *current_ev,
1165                                                    end_buf, &iwe, pos);
1166
1167                 pos = next;
1168         }
1169
1170         if (end > pos) {
1171                 memset(&iwe, 0, sizeof(iwe));
1172                 iwe.cmd = IWEVGENIE;
1173                 iwe.u.data.length = end - pos;
1174                 *current_ev = iwe_stream_add_point(info, *current_ev,
1175                                                    end_buf, &iwe, pos);
1176         }
1177 }
1178
1179 static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
1180 {
1181         unsigned long end = jiffies;
1182
1183         if (end >= start)
1184                 return jiffies_to_msecs(end - start);
1185
1186         return jiffies_to_msecs(end + (MAX_JIFFY_OFFSET - start) + 1);
1187 }
1188
1189 static char *
1190 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
1191               struct cfg80211_internal_bss *bss, char *current_ev,
1192               char *end_buf)
1193 {
1194         struct iw_event iwe;
1195         u8 *buf, *cfg, *p;
1196         u8 *ie = bss->pub.information_elements;
1197         int rem = bss->pub.len_information_elements, i, sig;
1198         bool ismesh = false;
1199
1200         memset(&iwe, 0, sizeof(iwe));
1201         iwe.cmd = SIOCGIWAP;
1202         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
1203         memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
1204         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1205                                           IW_EV_ADDR_LEN);
1206
1207         memset(&iwe, 0, sizeof(iwe));
1208         iwe.cmd = SIOCGIWFREQ;
1209         iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
1210         iwe.u.freq.e = 0;
1211         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1212                                           IW_EV_FREQ_LEN);
1213
1214         memset(&iwe, 0, sizeof(iwe));
1215         iwe.cmd = SIOCGIWFREQ;
1216         iwe.u.freq.m = bss->pub.channel->center_freq;
1217         iwe.u.freq.e = 6;
1218         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1219                                           IW_EV_FREQ_LEN);
1220
1221         if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
1222                 memset(&iwe, 0, sizeof(iwe));
1223                 iwe.cmd = IWEVQUAL;
1224                 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
1225                                      IW_QUAL_NOISE_INVALID |
1226                                      IW_QUAL_QUAL_UPDATED;
1227                 switch (wiphy->signal_type) {
1228                 case CFG80211_SIGNAL_TYPE_MBM:
1229                         sig = bss->pub.signal / 100;
1230                         iwe.u.qual.level = sig;
1231                         iwe.u.qual.updated |= IW_QUAL_DBM;
1232                         if (sig < -110)         /* rather bad */
1233                                 sig = -110;
1234                         else if (sig > -40)     /* perfect */
1235                                 sig = -40;
1236                         /* will give a range of 0 .. 70 */
1237                         iwe.u.qual.qual = sig + 110;
1238                         break;
1239                 case CFG80211_SIGNAL_TYPE_UNSPEC:
1240                         iwe.u.qual.level = bss->pub.signal;
1241                         /* will give range 0 .. 100 */
1242                         iwe.u.qual.qual = bss->pub.signal;
1243                         break;
1244                 default:
1245                         /* not reached */
1246                         break;
1247                 }
1248                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1249                                                   &iwe, IW_EV_QUAL_LEN);
1250         }
1251
1252         memset(&iwe, 0, sizeof(iwe));
1253         iwe.cmd = SIOCGIWENCODE;
1254         if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
1255                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
1256         else
1257                 iwe.u.data.flags = IW_ENCODE_DISABLED;
1258         iwe.u.data.length = 0;
1259         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1260                                           &iwe, "");
1261
1262         while (rem >= 2) {
1263                 /* invalid data */
1264                 if (ie[1] > rem - 2)
1265                         break;
1266
1267                 switch (ie[0]) {
1268                 case WLAN_EID_SSID:
1269                         memset(&iwe, 0, sizeof(iwe));
1270                         iwe.cmd = SIOCGIWESSID;
1271                         iwe.u.data.length = ie[1];
1272                         iwe.u.data.flags = 1;
1273                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1274                                                           &iwe, ie + 2);
1275                         break;
1276                 case WLAN_EID_MESH_ID:
1277                         memset(&iwe, 0, sizeof(iwe));
1278                         iwe.cmd = SIOCGIWESSID;
1279                         iwe.u.data.length = ie[1];
1280                         iwe.u.data.flags = 1;
1281                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1282                                                           &iwe, ie + 2);
1283                         break;
1284                 case WLAN_EID_MESH_CONFIG:
1285                         ismesh = true;
1286                         if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
1287                                 break;
1288                         buf = kmalloc(50, GFP_ATOMIC);
1289                         if (!buf)
1290                                 break;
1291                         cfg = ie + 2;
1292                         memset(&iwe, 0, sizeof(iwe));
1293                         iwe.cmd = IWEVCUSTOM;
1294                         sprintf(buf, "Mesh Network Path Selection Protocol ID: "
1295                                 "0x%02X", cfg[0]);
1296                         iwe.u.data.length = strlen(buf);
1297                         current_ev = iwe_stream_add_point(info, current_ev,
1298                                                           end_buf,
1299                                                           &iwe, buf);
1300                         sprintf(buf, "Path Selection Metric ID: 0x%02X",
1301                                 cfg[1]);
1302                         iwe.u.data.length = strlen(buf);
1303                         current_ev = iwe_stream_add_point(info, current_ev,
1304                                                           end_buf,
1305                                                           &iwe, buf);
1306                         sprintf(buf, "Congestion Control Mode ID: 0x%02X",
1307                                 cfg[2]);
1308                         iwe.u.data.length = strlen(buf);
1309                         current_ev = iwe_stream_add_point(info, current_ev,
1310                                                           end_buf,
1311                                                           &iwe, buf);
1312                         sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
1313                         iwe.u.data.length = strlen(buf);
1314                         current_ev = iwe_stream_add_point(info, current_ev,
1315                                                           end_buf,
1316                                                           &iwe, buf);
1317                         sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
1318                         iwe.u.data.length = strlen(buf);
1319                         current_ev = iwe_stream_add_point(info, current_ev,
1320                                                           end_buf,
1321                                                           &iwe, buf);
1322                         sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
1323                         iwe.u.data.length = strlen(buf);
1324                         current_ev = iwe_stream_add_point(info, current_ev,
1325                                                           end_buf,
1326                                                           &iwe, buf);
1327                         sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
1328                         iwe.u.data.length = strlen(buf);
1329                         current_ev = iwe_stream_add_point(info, current_ev,
1330                                                           end_buf,
1331                                                           &iwe, buf);
1332                         kfree(buf);
1333                         break;
1334                 case WLAN_EID_SUPP_RATES:
1335                 case WLAN_EID_EXT_SUPP_RATES:
1336                         /* display all supported rates in readable format */
1337                         p = current_ev + iwe_stream_lcp_len(info);
1338
1339                         memset(&iwe, 0, sizeof(iwe));
1340                         iwe.cmd = SIOCGIWRATE;
1341                         /* Those two flags are ignored... */
1342                         iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
1343
1344                         for (i = 0; i < ie[1]; i++) {
1345                                 iwe.u.bitrate.value =
1346                                         ((ie[i + 2] & 0x7f) * 500000);
1347                                 p = iwe_stream_add_value(info, current_ev, p,
1348                                                 end_buf, &iwe, IW_EV_PARAM_LEN);
1349                         }
1350                         current_ev = p;
1351                         break;
1352                 }
1353                 rem -= ie[1] + 2;
1354                 ie += ie[1] + 2;
1355         }
1356
1357         if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
1358             ismesh) {
1359                 memset(&iwe, 0, sizeof(iwe));
1360                 iwe.cmd = SIOCGIWMODE;
1361                 if (ismesh)
1362                         iwe.u.mode = IW_MODE_MESH;
1363                 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
1364                         iwe.u.mode = IW_MODE_MASTER;
1365                 else
1366                         iwe.u.mode = IW_MODE_ADHOC;
1367                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1368                                                   &iwe, IW_EV_UINT_LEN);
1369         }
1370
1371         buf = kmalloc(30, GFP_ATOMIC);
1372         if (buf) {
1373                 memset(&iwe, 0, sizeof(iwe));
1374                 iwe.cmd = IWEVCUSTOM;
1375                 sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->pub.tsf));
1376                 iwe.u.data.length = strlen(buf);
1377                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1378                                                   &iwe, buf);
1379                 memset(&iwe, 0, sizeof(iwe));
1380                 iwe.cmd = IWEVCUSTOM;
1381                 sprintf(buf, " Last beacon: %ums ago",
1382                         elapsed_jiffies_msecs(bss->ts));
1383                 iwe.u.data.length = strlen(buf);
1384                 current_ev = iwe_stream_add_point(info, current_ev,
1385                                                   end_buf, &iwe, buf);
1386                 kfree(buf);
1387         }
1388
1389         ieee80211_scan_add_ies(info, &bss->pub, &current_ev, end_buf);
1390
1391         return current_ev;
1392 }
1393
1394
1395 static int ieee80211_scan_results(struct cfg80211_registered_device *dev,
1396                                   struct iw_request_info *info,
1397                                   char *buf, size_t len)
1398 {
1399         char *current_ev = buf;
1400         char *end_buf = buf + len;
1401         struct cfg80211_internal_bss *bss;
1402
1403         spin_lock_bh(&dev->bss_lock);
1404         cfg80211_bss_expire(dev);
1405
1406         list_for_each_entry(bss, &dev->bss_list, list) {
1407                 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
1408                         spin_unlock_bh(&dev->bss_lock);
1409                         return -E2BIG;
1410                 }
1411                 current_ev = ieee80211_bss(&dev->wiphy, info, bss,
1412                                            current_ev, end_buf);
1413         }
1414         spin_unlock_bh(&dev->bss_lock);
1415         return current_ev - buf;
1416 }
1417
1418
1419 int cfg80211_wext_giwscan(struct net_device *dev,
1420                           struct iw_request_info *info,
1421                           struct iw_point *data, char *extra)
1422 {
1423         struct cfg80211_registered_device *rdev;
1424         int res;
1425
1426         if (!netif_running(dev))
1427                 return -ENETDOWN;
1428
1429         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1430
1431         if (IS_ERR(rdev))
1432                 return PTR_ERR(rdev);
1433
1434         if (rdev->scan_req) {
1435                 res = -EAGAIN;
1436                 goto out;
1437         }
1438
1439         res = ieee80211_scan_results(rdev, info, extra, data->length);
1440         data->length = 0;
1441         if (res >= 0) {
1442                 data->length = res;
1443                 res = 0;
1444         }
1445
1446  out:
1447         cfg80211_unlock_rdev(rdev);
1448         return res;
1449 }
1450 EXPORT_SYMBOL_GPL(cfg80211_wext_giwscan);
1451 #endif