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
  21 #define IEEE80211_SCAN_RESULT_EXPIRE    (15 * HZ)
  22
  23 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev, bool leak)
  24 {
  25         struct cfg80211_scan_request *request;
  26         struct net_device *dev;
  27 #ifdef CONFIG_CFG80211_WEXT
  28         union iwreq_data wrqu;
  29 #endif
  30
  31         ASSERT_RDEV_LOCK(rdev);
  32
  33         request = rdev->scan_req;
  34
  35         if (!request)
  36                 return;
  37
  38         dev = request->dev;
  39
  40         /*
  41          * This must be before sending the other events!
  42          * Otherwise, wpa_supplicant gets completely confused with
  43          * wext events.
  44          */
  45         cfg80211_sme_scan_done(dev);
  46
  47         if (request->aborted)
  48                 nl80211_send_scan_aborted(rdev, dev);
  49         else
  50                 nl80211_send_scan_done(rdev, dev);
  51
  52 #ifdef CONFIG_CFG80211_WEXT
  53         if (!request->aborted) {
  54                 memset(&wrqu, 0, sizeof(wrqu));
  55
  56                 wireless_send_event(dev, SIOCGIWSCAN, &wrqu, NULL);
  57         }
  58 #endif
  59
  60         dev_put(dev);
  61
  62         rdev->scan_req = NULL;
  63
  64         /*
  65          * OK. If this is invoked with "leak" then we can't
  66          * free this ... but we've cleaned it up anyway. The
  67          * driver failed to call the scan_done callback, so
  68          * all bets are off, it might still be trying to use
  69          * the scan request or not ... if it accesses the dev
  70          * in there (it shouldn't anyway) then it may crash.
  71          */
  72         if (!leak)
  73                 kfree(request);
  74 }
  75
  76 void __cfg80211_scan_done(struct work_struct *wk)
  77 {
  78         struct cfg80211_registered_device *rdev;
  79
  80         rdev = container_of(wk, struct cfg80211_registered_device,
  81                             scan_done_wk);
  82
  83         cfg80211_lock_rdev(rdev);
  84         ___cfg80211_scan_done(rdev, false);
  85         cfg80211_unlock_rdev(rdev);
  86 }
  87
  88 void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
  89 {
  90         WARN_ON(request != wiphy_to_dev(request->wiphy)->scan_req);
  91
  92         request->aborted = aborted;
  93         queue_work(cfg80211_wq, &wiphy_to_dev(request->wiphy)->scan_done_wk);
  94 }
  95 EXPORT_SYMBOL(cfg80211_scan_done);
  96
  97 void __cfg80211_sched_scan_results(struct work_struct *wk)
  98 {
  99         struct cfg80211_registered_device *rdev;
 100
 101         rdev = container_of(wk, struct cfg80211_registered_device,
 102                             sched_scan_results_wk);
 103
 104         mutex_lock(&rdev->sched_scan_mtx);
 105
 106         /* we don't have sched_scan_req anymore if the scan is stopping */
 107         if (rdev->sched_scan_req)
 108                 nl80211_send_sched_scan_results(rdev,
 109                                                 rdev->sched_scan_req->dev);
 110
 111         mutex_unlock(&rdev->sched_scan_mtx);
 112 }
 113
 114 void cfg80211_sched_scan_results(struct wiphy *wiphy)
 115 {
 116         /* ignore if we're not scanning */
 117         if (wiphy_to_dev(wiphy)->sched_scan_req)
 118                 queue_work(cfg80211_wq,
 119                            &wiphy_to_dev(wiphy)->sched_scan_results_wk);
 120 }
 121 EXPORT_SYMBOL(cfg80211_sched_scan_results);
 122
 123 void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
 124 {
 125         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
 126
 127         mutex_lock(&rdev->sched_scan_mtx);
 128         __cfg80211_stop_sched_scan(rdev, true);
 129         mutex_unlock(&rdev->sched_scan_mtx);
 130 }
 131 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
 132
 133 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
 134                                bool driver_initiated)
 135 {
 136         struct net_device *dev;
 137
 138         lockdep_assert_held(&rdev->sched_scan_mtx);
 139
 140         if (!rdev->sched_scan_req)
 141                 return -ENOENT;
 142
 143         dev = rdev->sched_scan_req->dev;
 144
 145         if (!driver_initiated) {
 146                 int err = rdev->ops->sched_scan_stop(&rdev->wiphy, dev);
 147                 if (err)
 148                         return err;
 149         }
 150
 151         nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED);
 152
 153         kfree(rdev->sched_scan_req);
 154         rdev->sched_scan_req = NULL;
 155
 156         return 0;
 157 }
 158
 159 static void bss_release(struct kref *ref)
 160 {
 161         struct cfg80211_internal_bss *bss;
 162
 163         bss = container_of(ref, struct cfg80211_internal_bss, ref);
 164         if (bss->pub.free_priv)
 165                 bss->pub.free_priv(&bss->pub);
 166
 167         if (bss->beacon_ies_allocated)
 168                 kfree(bss->pub.beacon_ies);
 169         if (bss->proberesp_ies_allocated)
 170                 kfree(bss->pub.proberesp_ies);
 171
 172         BUG_ON(atomic_read(&bss->hold));
 173
 174         kfree(bss);
 175 }
 176
 177 /* must hold dev->bss_lock! */
 178 void cfg80211_bss_age(struct cfg80211_registered_device *dev,
 179                       unsigned long age_secs)
 180 {
 181         struct cfg80211_internal_bss *bss;
 182         unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
 183
 184         list_for_each_entry(bss, &dev->bss_list, list) {
 185                 bss->ts -= age_jiffies;
 186         }
 187 }
 188
 189 /* must hold dev->bss_lock! */
 190 static void __cfg80211_unlink_bss(struct cfg80211_registered_device *dev,
 191                                   struct cfg80211_internal_bss *bss)
 192 {
 193         list_del_init(&bss->list);
 194         rb_erase(&bss->rbn, &dev->bss_tree);
 195         kref_put(&bss->ref, bss_release);
 196 }
 197
 198 /* must hold dev->bss_lock! */
 199 void cfg80211_bss_expire(struct cfg80211_registered_device *dev)
 200 {
 201         struct cfg80211_internal_bss *bss, *tmp;
 202         bool expired = false;
 203
 204         list_for_each_entry_safe(bss, tmp, &dev->bss_list, list) {
 205                 if (atomic_read(&bss->hold))
 206                         continue;
 207                 if (!time_after(jiffies, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE))
 208                         continue;
 209                 __cfg80211_unlink_bss(dev, bss);
 210                 expired = true;
 211         }
 212
 213         if (expired)
 214                 dev->bss_generation++;
 215 }
 216
 217 const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len)
 218 {
 219         while (len > 2 && ies[0] != eid) {
 220                 len -= ies[1] + 2;
 221                 ies += ies[1] + 2;
 222         }
 223         if (len < 2)
 224                 return NULL;
 225         if (len < 2 + ies[1])
 226                 return NULL;
 227         return ies;
 228 }
 229 EXPORT_SYMBOL(cfg80211_find_ie);
 230
 231 const u8 *cfg80211_find_vendor_ie(unsigned int oui, u8 oui_type,
 232                                   const u8 *ies, int len)
 233 {
 234         struct ieee80211_vendor_ie *ie;
 235         const u8 *pos = ies, *end = ies + len;
 236         int ie_oui;
 237
 238         while (pos < end) {
 239                 pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos,
 240                                        end - pos);
 241                 if (!pos)
 242                         return NULL;
 243
 244                 if (end - pos < sizeof(*ie))
 245                         return NULL;
 246
 247                 ie = (struct ieee80211_vendor_ie *)pos;
 248                 ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2];
 249                 if (ie_oui == oui && ie->oui_type == oui_type)
 250                         return pos;
 251
 252                 pos += 2 + ie->len;
 253         }
 254         return NULL;
 255 }
 256 EXPORT_SYMBOL(cfg80211_find_vendor_ie);
 257
 258 static int cmp_ies(u8 num, u8 *ies1, size_t len1, u8 *ies2, size_t len2)
 259 {
 260         const u8 *ie1 = cfg80211_find_ie(num, ies1, len1);
 261         const u8 *ie2 = cfg80211_find_ie(num, ies2, len2);
 262
 263         /* equal if both missing */
 264         if (!ie1 && !ie2)
 265                 return 0;
 266         /* sort missing IE before (left of) present IE */
 267         if (!ie1)
 268                 return -1;
 269         if (!ie2)
 270                 return 1;
 271
 272         /* sort by length first, then by contents */
 273         if (ie1[1] != ie2[1])
 274                 return ie2[1] - ie1[1];
 275         return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
 276 }
 277
 278 static bool is_bss(struct cfg80211_bss *a,
 279                    const u8 *bssid,
 280                    const u8 *ssid, size_t ssid_len)
 281 {
 282         const u8 *ssidie;
 283
 284         if (bssid && compare_ether_addr(a->bssid, bssid))
 285                 return false;
 286
 287         if (!ssid)
 288                 return true;
 289
 290         ssidie = cfg80211_find_ie(WLAN_EID_SSID,
 291                                   a->information_elements,
 292                                   a->len_information_elements);
 293         if (!ssidie)
 294                 return false;
 295         if (ssidie[1] != ssid_len)
 296                 return false;
 297         return memcmp(ssidie + 2, ssid, ssid_len) == 0;
 298 }
 299
 300 static bool is_mesh_bss(struct cfg80211_bss *a)
 301 {
 302         const u8 *ie;
 303
 304         if (!WLAN_CAPABILITY_IS_STA_BSS(a->capability))
 305                 return false;
 306
 307         ie = cfg80211_find_ie(WLAN_EID_MESH_ID,
 308                               a->information_elements,
 309                               a->len_information_elements);
 310         if (!ie)
 311                 return false;
 312
 313         ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
 314                               a->information_elements,
 315                               a->len_information_elements);
 316         if (!ie)
 317                 return false;
 318
 319         return true;
 320 }
 321
 322 static bool is_mesh(struct cfg80211_bss *a,
 323                     const u8 *meshid, size_t meshidlen,
 324                     const u8 *meshcfg)
 325 {
 326         const u8 *ie;
 327
 328         if (!WLAN_CAPABILITY_IS_STA_BSS(a->capability))
 329                 return false;
 330
 331         ie = cfg80211_find_ie(WLAN_EID_MESH_ID,
 332                               a->information_elements,
 333                               a->len_information_elements);
 334         if (!ie)
 335                 return false;
 336         if (ie[1] != meshidlen)
 337                 return false;
 338         if (memcmp(ie + 2, meshid, meshidlen))
 339                 return false;
 340
 341         ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
 342                               a->information_elements,
 343                               a->len_information_elements);
 344         if (!ie)
 345                 return false;
 346         if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
 347                 return false;
 348
 349         /*
 350          * Ignore mesh capability (last two bytes of the IE) when
 351          * comparing since that may differ between stations taking
 352          * part in the same mesh.
 353          */
 354         return memcmp(ie + 2, meshcfg,
 355             sizeof(struct ieee80211_meshconf_ie) - 2) == 0;
 356 }
 357
 358 static int cmp_bss_core(struct cfg80211_bss *a,
 359                         struct cfg80211_bss *b)
 360 {
 361         int r;
 362
 363         if (a->channel != b->channel)
 364                 return b->channel->center_freq - a->channel->center_freq;
 365
 366         if (is_mesh_bss(a) && is_mesh_bss(b)) {
 367                 r = cmp_ies(WLAN_EID_MESH_ID,
 368                             a->information_elements,
 369                             a->len_information_elements,
 370                             b->information_elements,
 371                             b->len_information_elements);
 372                 if (r)
 373                         return r;
 374                 return cmp_ies(WLAN_EID_MESH_CONFIG,
 375                                a->information_elements,
 376                                a->len_information_elements,
 377                                b->information_elements,
 378                                b->len_information_elements);
 379         }
 380
 381         return memcmp(a->bssid, b->bssid, ETH_ALEN);
 382 }
 383
 384 static int cmp_bss(struct cfg80211_bss *a,
 385                    struct cfg80211_bss *b)
 386 {
 387         int r;
 388
 389         r = cmp_bss_core(a, b);
 390         if (r)
 391                 return r;
 392
 393         return cmp_ies(WLAN_EID_SSID,
 394                        a->information_elements,
 395                        a->len_information_elements,
 396                        b->information_elements,
 397                        b->len_information_elements);
 398 }
 399
 400 static int cmp_hidden_bss(struct cfg80211_bss *a,
 401                    struct cfg80211_bss *b)
 402 {
 403         const u8 *ie1;
 404         const u8 *ie2;
 405         int i;
 406         int r;
 407
 408         r = cmp_bss_core(a, b);
 409         if (r)
 410                 return r;
 411
 412         ie1 = cfg80211_find_ie(WLAN_EID_SSID,
 413                         a->information_elements,
 414                         a->len_information_elements);
 415         ie2 = cfg80211_find_ie(WLAN_EID_SSID,
 416                         b->information_elements,
 417                         b->len_information_elements);
 418
 419         /* Key comparator must use same algorithm in any rb-tree
 420          * search function (order is important), otherwise ordering
 421          * of items in the tree is broken and search gives incorrect
 422          * results. This code uses same order as cmp_ies() does. */
 423
 424         /* sort missing IE before (left of) present IE */
 425         if (!ie1)
 426                 return -1;
 427         if (!ie2)
 428                 return 1;
 429
 430         /* zero-size SSID is used as an indication of the hidden bss */
 431         if (!ie2[1])
 432                 return 0;
 433
 434         /* sort by length first, then by contents */
 435         if (ie1[1] != ie2[1])
 436                 return ie2[1] - ie1[1];
 437
 438         /* zeroed SSID ie is another indication of a hidden bss */
 439         for (i = 0; i < ie2[1]; i++)
 440                 if (ie2[i + 2])
 441                         return -1;
 442
 443         return 0;
 444 }
 445
 446 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
 447                                       struct ieee80211_channel *channel,
 448                                       const u8 *bssid,
 449                                       const u8 *ssid, size_t ssid_len,
 450                                       u16 capa_mask, u16 capa_val)
 451 {
 452         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 453         struct cfg80211_internal_bss *bss, *res = NULL;
 454         unsigned long now = jiffies;
 455
 456         spin_lock_bh(&dev->bss_lock);
 457
 458         list_for_each_entry(bss, &dev->bss_list, list) {
 459                 if ((bss->pub.capability & capa_mask) != capa_val)
 460                         continue;
 461                 if (channel && bss->pub.channel != channel)
 462                         continue;
 463                 /* Don't get expired BSS structs */
 464                 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
 465                     !atomic_read(&bss->hold))
 466                         continue;
 467                 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
 468                         res = bss;
 469                         kref_get(&res->ref);
 470                         break;
 471                 }
 472         }
 473
 474         spin_unlock_bh(&dev->bss_lock);
 475         if (!res)
 476                 return NULL;
 477         return &res->pub;
 478 }
 479 EXPORT_SYMBOL(cfg80211_get_bss);
 480
 481 struct cfg80211_bss *cfg80211_get_mesh(struct wiphy *wiphy,
 482                                        struct ieee80211_channel *channel,
 483                                        const u8 *meshid, size_t meshidlen,
 484                                        const u8 *meshcfg)
 485 {
 486         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 487         struct cfg80211_internal_bss *bss, *res = NULL;
 488
 489         spin_lock_bh(&dev->bss_lock);
 490
 491         list_for_each_entry(bss, &dev->bss_list, list) {
 492                 if (channel && bss->pub.channel != channel)
 493                         continue;
 494                 if (is_mesh(&bss->pub, meshid, meshidlen, meshcfg)) {
 495                         res = bss;
 496                         kref_get(&res->ref);
 497                         break;
 498                 }
 499         }
 500
 501         spin_unlock_bh(&dev->bss_lock);
 502         if (!res)
 503                 return NULL;
 504         return &res->pub;
 505 }
 506 EXPORT_SYMBOL(cfg80211_get_mesh);
 507
 508
 509 static void rb_insert_bss(struct cfg80211_registered_device *dev,
 510                           struct cfg80211_internal_bss *bss)
 511 {
 512         struct rb_node **p = &dev->bss_tree.rb_node;
 513         struct rb_node *parent = NULL;
 514         struct cfg80211_internal_bss *tbss;
 515         int cmp;
 516
 517         while (*p) {
 518                 parent = *p;
 519                 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
 520
 521                 cmp = cmp_bss(&bss->pub, &tbss->pub);
 522
 523                 if (WARN_ON(!cmp)) {
 524                         /* will sort of leak this BSS */
 525                         return;
 526                 }
 527
 528                 if (cmp < 0)
 529                         p = &(*p)->rb_left;
 530                 else
 531                         p = &(*p)->rb_right;
 532         }
 533
 534         rb_link_node(&bss->rbn, parent, p);
 535         rb_insert_color(&bss->rbn, &dev->bss_tree);
 536 }
 537
 538 static struct cfg80211_internal_bss *
 539 rb_find_bss(struct cfg80211_registered_device *dev,
 540             struct cfg80211_internal_bss *res)
 541 {
 542         struct rb_node *n = dev->bss_tree.rb_node;
 543         struct cfg80211_internal_bss *bss;
 544         int r;
 545
 546         while (n) {
 547                 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
 548                 r = cmp_bss(&res->pub, &bss->pub);
 549
 550                 if (r == 0)
 551                         return bss;
 552                 else if (r < 0)
 553                         n = n->rb_left;
 554                 else
 555                         n = n->rb_right;
 556         }
 557
 558         return NULL;
 559 }
 560
 561 static struct cfg80211_internal_bss *
 562 rb_find_hidden_bss(struct cfg80211_registered_device *dev,
 563             struct cfg80211_internal_bss *res)
 564 {
 565         struct rb_node *n = dev->bss_tree.rb_node;
 566         struct cfg80211_internal_bss *bss;
 567         int r;
 568
 569         while (n) {
 570                 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
 571                 r = cmp_hidden_bss(&res->pub, &bss->pub);
 572
 573                 if (r == 0)
 574                         return bss;
 575                 else if (r < 0)
 576                         n = n->rb_left;
 577                 else
 578                         n = n->rb_right;
 579         }
 580
 581         return NULL;
 582 }
 583
 584 static void
 585 copy_hidden_ies(struct cfg80211_internal_bss *res,
 586                  struct cfg80211_internal_bss *hidden)
 587 {
 588         if (unlikely(res->pub.beacon_ies))
 589                 return;
 590         if (WARN_ON(!hidden->pub.beacon_ies))
 591                 return;
 592
 593         res->pub.beacon_ies = kmalloc(hidden->pub.len_beacon_ies, GFP_ATOMIC);
 594         if (unlikely(!res->pub.beacon_ies))
 595                 return;
 596
 597         res->beacon_ies_allocated = true;
 598         res->pub.len_beacon_ies = hidden->pub.len_beacon_ies;
 599         memcpy(res->pub.beacon_ies, hidden->pub.beacon_ies,
 600                         res->pub.len_beacon_ies);
 601 }
 602
 603 static struct cfg80211_internal_bss *
 604 cfg80211_bss_update(struct cfg80211_registered_device *dev,
 605                     struct cfg80211_internal_bss *res)
 606 {
 607         struct cfg80211_internal_bss *found = NULL;
 608
 609         /*
 610          * The reference to "res" is donated to this function.
 611          */
 612
 613         if (WARN_ON(!res->pub.channel)) {
 614                 kref_put(&res->ref, bss_release);
 615                 return NULL;
 616         }
 617
 618         res->ts = jiffies;
 619
 620         spin_lock_bh(&dev->bss_lock);
 621
 622         found = rb_find_bss(dev, res);
 623
 624         if (found) {
 625                 found->pub.beacon_interval = res->pub.beacon_interval;
 626                 found->pub.tsf = res->pub.tsf;
 627                 found->pub.signal = res->pub.signal;
 628                 found->pub.capability = res->pub.capability;
 629                 found->ts = res->ts;
 630
 631                 /* Update IEs */
 632                 if (res->pub.proberesp_ies) {
 633                         size_t used = dev->wiphy.bss_priv_size + sizeof(*res);
 634                         size_t ielen = res->pub.len_proberesp_ies;
 635
 636                         if (found->pub.proberesp_ies &&
 637                             !found->proberesp_ies_allocated &&
 638                             ksize(found) >= used + ielen) {
 639                                 memcpy(found->pub.proberesp_ies,
 640                                        res->pub.proberesp_ies, ielen);
 641                                 found->pub.len_proberesp_ies = ielen;
 642                         } else {
 643                                 u8 *ies = found->pub.proberesp_ies;
 644
 645                                 if (found->proberesp_ies_allocated)
 646                                         ies = krealloc(ies, ielen, GFP_ATOMIC);
 647                                 else
 648                                         ies = kmalloc(ielen, GFP_ATOMIC);
 649
 650                                 if (ies) {
 651                                         memcpy(ies, res->pub.proberesp_ies,
 652                                                ielen);
 653                                         found->proberesp_ies_allocated = true;
 654                                         found->pub.proberesp_ies = ies;
 655                                         found->pub.len_proberesp_ies = ielen;
 656                                 }
 657                         }
 658
 659                         /* Override possible earlier Beacon frame IEs */
 660                         found->pub.information_elements =
 661                                 found->pub.proberesp_ies;
 662                         found->pub.len_information_elements =
 663                                 found->pub.len_proberesp_ies;
 664                 }
 665                 if (res->pub.beacon_ies) {
 666                         size_t used = dev->wiphy.bss_priv_size + sizeof(*res);
 667                         size_t ielen = res->pub.len_beacon_ies;
 668                         bool information_elements_is_beacon_ies =
 669                                 (found->pub.information_elements ==
 670                                  found->pub.beacon_ies);
 671
 672                         if (found->pub.beacon_ies &&
 673                             !found->beacon_ies_allocated &&
 674                             ksize(found) >= used + ielen) {
 675                                 memcpy(found->pub.beacon_ies,
 676                                        res->pub.beacon_ies, ielen);
 677                                 found->pub.len_beacon_ies = ielen;
 678                         } else {
 679                                 u8 *ies = found->pub.beacon_ies;
 680
 681                                 if (found->beacon_ies_allocated)
 682                                         ies = krealloc(ies, ielen, GFP_ATOMIC);
 683                                 else
 684                                         ies = kmalloc(ielen, GFP_ATOMIC);
 685
 686                                 if (ies) {
 687                                         memcpy(ies, res->pub.beacon_ies,
 688                                                ielen);
 689                                         found->beacon_ies_allocated = true;
 690                                         found->pub.beacon_ies = ies;
 691                                         found->pub.len_beacon_ies = ielen;
 692                                 }
 693                         }
 694
 695                         /* Override IEs if they were from a beacon before */
 696                         if (information_elements_is_beacon_ies) {
 697                                 found->pub.information_elements =
 698                                         found->pub.beacon_ies;
 699                                 found->pub.len_information_elements =
 700                                         found->pub.len_beacon_ies;
 701                         }
 702                 }
 703
 704                 kref_put(&res->ref, bss_release);
 705         } else {
 706                 struct cfg80211_internal_bss *hidden;
 707
 708                 /* First check if the beacon is a probe response from
 709                  * a hidden bss. If so, copy beacon ies (with nullified
 710                  * ssid) into the probe response bss entry (with real ssid).
 711                  * It is required basically for PSM implementation
 712                  * (probe responses do not contain tim ie) */
 713
 714                 /* TODO: The code is not trying to update existing probe
 715                  * response bss entries when beacon ies are
 716                  * getting changed. */
 717                 hidden = rb_find_hidden_bss(dev, res);
 718                 if (hidden)
 719                         copy_hidden_ies(res, hidden);
 720
 721                 /* this "consumes" the reference */
 722                 list_add_tail(&res->list, &dev->bss_list);
 723                 rb_insert_bss(dev, res);
 724                 found = res;
 725         }
 726
 727         dev->bss_generation++;
 728         spin_unlock_bh(&dev->bss_lock);
 729
 730         kref_get(&found->ref);
 731         return found;
 732 }
 733
 734 struct cfg80211_bss*
 735 cfg80211_inform_bss(struct wiphy *wiphy,
 736                     struct ieee80211_channel *channel,
 737                     const u8 *bssid,
 738                     u64 timestamp, u16 capability, u16 beacon_interval,
 739                     const u8 *ie, size_t ielen,
 740                     s32 signal, gfp_t gfp)
 741 {
 742         struct cfg80211_internal_bss *res;
 743         size_t privsz;
 744
 745         if (WARN_ON(!wiphy))
 746                 return NULL;
 747
 748         privsz = wiphy->bss_priv_size;
 749
 750         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
 751                         (signal < 0 || signal > 100)))
 752                 return NULL;
 753
 754         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
 755         if (!res)
 756                 return NULL;
 757
 758         memcpy(res->pub.bssid, bssid, ETH_ALEN);
 759         res->pub.channel = channel;
 760         res->pub.signal = signal;
 761         res->pub.tsf = timestamp;
 762         res->pub.beacon_interval = beacon_interval;
 763         res->pub.capability = capability;
 764         /*
 765          * Since we do not know here whether the IEs are from a Beacon or Probe
 766          * Response frame, we need to pick one of the options and only use it
 767          * with the driver that does not provide the full Beacon/Probe Response
 768          * frame. Use Beacon frame pointer to avoid indicating that this should
 769          * override the information_elements pointer should we have received an
 770          * earlier indication of Probe Response data.
 771          *
 772          * The initial buffer for the IEs is allocated with the BSS entry and
 773          * is located after the private area.
 774          */
 775         res->pub.beacon_ies = (u8 *)res + sizeof(*res) + privsz;
 776         memcpy(res->pub.beacon_ies, ie, ielen);
 777         res->pub.len_beacon_ies = ielen;
 778         res->pub.information_elements = res->pub.beacon_ies;
 779         res->pub.len_information_elements = res->pub.len_beacon_ies;
 780
 781         kref_init(&res->ref);
 782
 783         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res);
 784         if (!res)
 785                 return NULL;
 786
 787         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 788                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 789
 790         /* cfg80211_bss_update gives us a referenced result */
 791         return &res->pub;
 792 }
 793 EXPORT_SYMBOL(cfg80211_inform_bss);
 794
 795 struct cfg80211_bss *
 796 cfg80211_inform_bss_frame(struct wiphy *wiphy,
 797                           struct ieee80211_channel *channel,
 798                           struct ieee80211_mgmt *mgmt, size_t len,
 799                           s32 signal, gfp_t gfp)
 800 {
 801         struct cfg80211_internal_bss *res;
 802         size_t ielen = len - offsetof(struct ieee80211_mgmt,
 803                                       u.probe_resp.variable);
 804         size_t privsz;
 805
 806         if (WARN_ON(!mgmt))
 807                 return NULL;
 808
 809         if (WARN_ON(!wiphy))
 810                 return NULL;
 811
 812         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
 813                     (signal < 0 || signal > 100)))
 814                 return NULL;
 815
 816         if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
 817                 return NULL;
 818
 819         privsz = wiphy->bss_priv_size;
 820
 821         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
 822         if (!res)
 823                 return NULL;
 824
 825         memcpy(res->pub.bssid, mgmt->bssid, ETH_ALEN);
 826         res->pub.channel = channel;
 827         res->pub.signal = signal;
 828         res->pub.tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
 829         res->pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
 830         res->pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
 831         /*
 832          * The initial buffer for the IEs is allocated with the BSS entry and
 833          * is located after the private area.
 834          */
 835         if (ieee80211_is_probe_resp(mgmt->frame_control)) {
 836                 res->pub.proberesp_ies = (u8 *) res + sizeof(*res) + privsz;
 837                 memcpy(res->pub.proberesp_ies, mgmt->u.probe_resp.variable,
 838                        ielen);
 839                 res->pub.len_proberesp_ies = ielen;
 840                 res->pub.information_elements = res->pub.proberesp_ies;
 841                 res->pub.len_information_elements = res->pub.len_proberesp_ies;
 842         } else {
 843                 res->pub.beacon_ies = (u8 *) res + sizeof(*res) + privsz;
 844                 memcpy(res->pub.beacon_ies, mgmt->u.beacon.variable, ielen);
 845                 res->pub.len_beacon_ies = ielen;
 846                 res->pub.information_elements = res->pub.beacon_ies;
 847                 res->pub.len_information_elements = res->pub.len_beacon_ies;
 848         }
 849
 850         kref_init(&res->ref);
 851
 852         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res);
 853         if (!res)
 854                 return NULL;
 855
 856         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 857                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 858
 859         /* cfg80211_bss_update gives us a referenced result */
 860         return &res->pub;
 861 }
 862 EXPORT_SYMBOL(cfg80211_inform_bss_frame);
 863
 864 void cfg80211_put_bss(struct cfg80211_bss *pub)
 865 {
 866         struct cfg80211_internal_bss *bss;
 867
 868         if (!pub)
 869                 return;
 870
 871         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 872         kref_put(&bss->ref, bss_release);
 873 }
 874 EXPORT_SYMBOL(cfg80211_put_bss);
 875
 876 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
 877 {
 878         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 879         struct cfg80211_internal_bss *bss;
 880
 881         if (WARN_ON(!pub))
 882                 return;
 883
 884         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 885
 886         spin_lock_bh(&dev->bss_lock);
 887         if (!list_empty(&bss->list)) {
 888                 __cfg80211_unlink_bss(dev, bss);
 889                 dev->bss_generation++;
 890         }
 891         spin_unlock_bh(&dev->bss_lock);
 892 }
 893 EXPORT_SYMBOL(cfg80211_unlink_bss);
 894
 895 #ifdef CONFIG_CFG80211_WEXT
 896 int cfg80211_wext_siwscan(struct net_device *dev,
 897                           struct iw_request_info *info,
 898                           union iwreq_data *wrqu, char *extra)
 899 {
 900         struct cfg80211_registered_device *rdev;
 901         struct wiphy *wiphy;
 902         struct iw_scan_req *wreq = NULL;
 903         struct cfg80211_scan_request *creq = NULL;
 904         int i, err, n_channels = 0;
 905         enum ieee80211_band band;
 906
 907         if (!netif_running(dev))
 908                 return -ENETDOWN;
 909
 910         if (wrqu->data.length == sizeof(struct iw_scan_req))
 911                 wreq = (struct iw_scan_req *)extra;
 912
 913         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
 914
 915         if (IS_ERR(rdev))
 916                 return PTR_ERR(rdev);
 917
 918         if (rdev->scan_req) {
 919                 err = -EBUSY;
 920                 goto out;
 921         }
 922
 923         wiphy = &rdev->wiphy;
 924
 925         /* Determine number of channels, needed to allocate creq */
 926         if (wreq && wreq->num_channels)
 927                 n_channels = wreq->num_channels;
 928         else {
 929                 for (band = 0; band < IEEE80211_NUM_BANDS; band++)
 930                         if (wiphy->bands[band])
 931                                 n_channels += wiphy->bands[band]->n_channels;
 932         }
 933
 934         creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
 935                        n_channels * sizeof(void *),
 936                        GFP_ATOMIC);
 937         if (!creq) {
 938                 err = -ENOMEM;
 939                 goto out;
 940         }
 941
 942         creq->wiphy = wiphy;
 943         creq->dev = dev;
 944         /* SSIDs come after channels */
 945         creq->ssids = (void *)&creq->channels[n_channels];
 946         creq->n_channels = n_channels;
 947         creq->n_ssids = 1;
 948
 949         /* translate "Scan on frequencies" request */
 950         i = 0;
 951         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
 952                 int j;
 953
 954                 if (!wiphy->bands[band])
 955                         continue;
 956
 957                 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
 958                         /* ignore disabled channels */
 959                         if (wiphy->bands[band]->channels[j].flags &
 960                                                 IEEE80211_CHAN_DISABLED)
 961                                 continue;
 962
 963                         /* If we have a wireless request structure and the
 964                          * wireless request specifies frequencies, then search
 965                          * for the matching hardware channel.
 966                          */
 967                         if (wreq && wreq->num_channels) {
 968                                 int k;
 969                                 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
 970                                 for (k = 0; k < wreq->num_channels; k++) {
 971                                         int wext_freq = cfg80211_wext_freq(wiphy, &wreq->channel_list[k]);
 972                                         if (wext_freq == wiphy_freq)
 973                                                 goto wext_freq_found;
 974                                 }
 975                                 goto wext_freq_not_found;
 976                         }
 977
 978                 wext_freq_found:
 979                         creq->channels[i] = &wiphy->bands[band]->channels[j];
 980                         i++;
 981                 wext_freq_not_found: ;
 982                 }
 983         }
 984         /* No channels found? */
 985         if (!i) {
 986                 err = -EINVAL;
 987                 goto out;
 988         }
 989
 990         /* Set real number of channels specified in creq->channels[] */
 991         creq->n_channels = i;
 992
 993         /* translate "Scan for SSID" request */
 994         if (wreq) {
 995                 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
 996                         if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
 997                                 err = -EINVAL;
 998                                 goto out;
 999                         }
1000                         memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
1001                         creq->ssids[0].ssid_len = wreq->essid_len;
1002                 }
1003                 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
1004                         creq->n_ssids = 0;
1005         }
1006
1007         for (i = 0; i < IEEE80211_NUM_BANDS; i++)
1008                 if (wiphy->bands[i])
1009                         creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
1010
1011         rdev->scan_req = creq;
1012         err = rdev->ops->scan(wiphy, dev, creq);
1013         if (err) {
1014                 rdev->scan_req = NULL;
1015                 /* creq will be freed below */
1016         } else {
1017                 nl80211_send_scan_start(rdev, dev);
1018                 /* creq now owned by driver */
1019                 creq = NULL;
1020                 dev_hold(dev);
1021         }
1022  out:
1023         kfree(creq);
1024         cfg80211_unlock_rdev(rdev);
1025         return err;
1026 }
1027 EXPORT_SYMBOL_GPL(cfg80211_wext_siwscan);
1028
1029 static void ieee80211_scan_add_ies(struct iw_request_info *info,
1030                                    struct cfg80211_bss *bss,
1031                                    char **current_ev, char *end_buf)
1032 {
1033         u8 *pos, *end, *next;
1034         struct iw_event iwe;
1035
1036         if (!bss->information_elements ||
1037             !bss->len_information_elements)
1038                 return;
1039
1040         /*
1041          * If needed, fragment the IEs buffer (at IE boundaries) into short
1042          * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
1043          */
1044         pos = bss->information_elements;
1045         end = pos + bss->len_information_elements;
1046
1047         while (end - pos > IW_GENERIC_IE_MAX) {
1048                 next = pos + 2 + pos[1];
1049                 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
1050                         next = next + 2 + next[1];
1051
1052                 memset(&iwe, 0, sizeof(iwe));
1053                 iwe.cmd = IWEVGENIE;
1054                 iwe.u.data.length = next - pos;
1055                 *current_ev = iwe_stream_add_point(info, *current_ev,
1056                                                    end_buf, &iwe, pos);
1057
1058                 pos = next;
1059         }
1060
1061         if (end > pos) {
1062                 memset(&iwe, 0, sizeof(iwe));
1063                 iwe.cmd = IWEVGENIE;
1064                 iwe.u.data.length = end - pos;
1065                 *current_ev = iwe_stream_add_point(info, *current_ev,
1066                                                    end_buf, &iwe, pos);
1067         }
1068 }
1069
1070 static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
1071 {
1072         unsigned long end = jiffies;
1073
1074         if (end >= start)
1075                 return jiffies_to_msecs(end - start);
1076
1077         return jiffies_to_msecs(end + (MAX_JIFFY_OFFSET - start) + 1);
1078 }
1079
1080 static char *
1081 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
1082               struct cfg80211_internal_bss *bss, char *current_ev,
1083               char *end_buf)
1084 {
1085         struct iw_event iwe;
1086         u8 *buf, *cfg, *p;
1087         u8 *ie = bss->pub.information_elements;
1088         int rem = bss->pub.len_information_elements, i, sig;
1089         bool ismesh = false;
1090
1091         memset(&iwe, 0, sizeof(iwe));
1092         iwe.cmd = SIOCGIWAP;
1093         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
1094         memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
1095         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1096                                           IW_EV_ADDR_LEN);
1097
1098         memset(&iwe, 0, sizeof(iwe));
1099         iwe.cmd = SIOCGIWFREQ;
1100         iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
1101         iwe.u.freq.e = 0;
1102         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1103                                           IW_EV_FREQ_LEN);
1104
1105         memset(&iwe, 0, sizeof(iwe));
1106         iwe.cmd = SIOCGIWFREQ;
1107         iwe.u.freq.m = bss->pub.channel->center_freq;
1108         iwe.u.freq.e = 6;
1109         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1110                                           IW_EV_FREQ_LEN);
1111
1112         if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
1113                 memset(&iwe, 0, sizeof(iwe));
1114                 iwe.cmd = IWEVQUAL;
1115                 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
1116                                      IW_QUAL_NOISE_INVALID |
1117                                      IW_QUAL_QUAL_UPDATED;
1118                 switch (wiphy->signal_type) {
1119                 case CFG80211_SIGNAL_TYPE_MBM:
1120                         sig = bss->pub.signal / 100;
1121                         iwe.u.qual.level = sig;
1122                         iwe.u.qual.updated |= IW_QUAL_DBM;
1123                         if (sig < -110)         /* rather bad */
1124                                 sig = -110;
1125                         else if (sig > -40)     /* perfect */
1126                                 sig = -40;
1127                         /* will give a range of 0 .. 70 */
1128                         iwe.u.qual.qual = sig + 110;
1129                         break;
1130                 case CFG80211_SIGNAL_TYPE_UNSPEC:
1131                         iwe.u.qual.level = bss->pub.signal;
1132                         /* will give range 0 .. 100 */
1133                         iwe.u.qual.qual = bss->pub.signal;
1134                         break;
1135                 default:
1136                         /* not reached */
1137                         break;
1138                 }
1139                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1140                                                   &iwe, IW_EV_QUAL_LEN);
1141         }
1142
1143         memset(&iwe, 0, sizeof(iwe));
1144         iwe.cmd = SIOCGIWENCODE;
1145         if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
1146                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
1147         else
1148                 iwe.u.data.flags = IW_ENCODE_DISABLED;
1149         iwe.u.data.length = 0;
1150         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1151                                           &iwe, "");
1152
1153         while (rem >= 2) {
1154                 /* invalid data */
1155                 if (ie[1] > rem - 2)
1156                         break;
1157
1158                 switch (ie[0]) {
1159                 case WLAN_EID_SSID:
1160                         memset(&iwe, 0, sizeof(iwe));
1161                         iwe.cmd = SIOCGIWESSID;
1162                         iwe.u.data.length = ie[1];
1163                         iwe.u.data.flags = 1;
1164                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1165                                                           &iwe, ie + 2);
1166                         break;
1167                 case WLAN_EID_MESH_ID:
1168                         memset(&iwe, 0, sizeof(iwe));
1169                         iwe.cmd = SIOCGIWESSID;
1170                         iwe.u.data.length = ie[1];
1171                         iwe.u.data.flags = 1;
1172                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1173                                                           &iwe, ie + 2);
1174                         break;
1175                 case WLAN_EID_MESH_CONFIG:
1176                         ismesh = true;
1177                         if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
1178                                 break;
1179                         buf = kmalloc(50, GFP_ATOMIC);
1180                         if (!buf)
1181                                 break;
1182                         cfg = ie + 2;
1183                         memset(&iwe, 0, sizeof(iwe));
1184                         iwe.cmd = IWEVCUSTOM;
1185                         sprintf(buf, "Mesh Network Path Selection Protocol ID: "
1186                                 "0x%02X", cfg[0]);
1187                         iwe.u.data.length = strlen(buf);
1188                         current_ev = iwe_stream_add_point(info, current_ev,
1189                                                           end_buf,
1190                                                           &iwe, buf);
1191                         sprintf(buf, "Path Selection Metric ID: 0x%02X",
1192                                 cfg[1]);
1193                         iwe.u.data.length = strlen(buf);
1194                         current_ev = iwe_stream_add_point(info, current_ev,
1195                                                           end_buf,
1196                                                           &iwe, buf);
1197                         sprintf(buf, "Congestion Control Mode ID: 0x%02X",
1198                                 cfg[2]);
1199                         iwe.u.data.length = strlen(buf);
1200                         current_ev = iwe_stream_add_point(info, current_ev,
1201                                                           end_buf,
1202                                                           &iwe, buf);
1203                         sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
1204                         iwe.u.data.length = strlen(buf);
1205                         current_ev = iwe_stream_add_point(info, current_ev,
1206                                                           end_buf,
1207                                                           &iwe, buf);
1208                         sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
1209                         iwe.u.data.length = strlen(buf);
1210                         current_ev = iwe_stream_add_point(info, current_ev,
1211                                                           end_buf,
1212                                                           &iwe, buf);
1213                         sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
1214                         iwe.u.data.length = strlen(buf);
1215                         current_ev = iwe_stream_add_point(info, current_ev,
1216                                                           end_buf,
1217                                                           &iwe, buf);
1218                         sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
1219                         iwe.u.data.length = strlen(buf);
1220                         current_ev = iwe_stream_add_point(info, current_ev,
1221                                                           end_buf,
1222                                                           &iwe, buf);
1223                         kfree(buf);
1224                         break;
1225                 case WLAN_EID_SUPP_RATES:
1226                 case WLAN_EID_EXT_SUPP_RATES:
1227                         /* display all supported rates in readable format */
1228                         p = current_ev + iwe_stream_lcp_len(info);
1229
1230                         memset(&iwe, 0, sizeof(iwe));
1231                         iwe.cmd = SIOCGIWRATE;
1232                         /* Those two flags are ignored... */
1233                         iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
1234
1235                         for (i = 0; i < ie[1]; i++) {
1236                                 iwe.u.bitrate.value =
1237                                         ((ie[i + 2] & 0x7f) * 500000);
1238                                 p = iwe_stream_add_value(info, current_ev, p,
1239                                                 end_buf, &iwe, IW_EV_PARAM_LEN);
1240                         }
1241                         current_ev = p;
1242                         break;
1243                 }
1244                 rem -= ie[1] + 2;
1245                 ie += ie[1] + 2;
1246         }
1247
1248         if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
1249             ismesh) {
1250                 memset(&iwe, 0, sizeof(iwe));
1251                 iwe.cmd = SIOCGIWMODE;
1252                 if (ismesh)
1253                         iwe.u.mode = IW_MODE_MESH;
1254                 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
1255                         iwe.u.mode = IW_MODE_MASTER;
1256                 else
1257                         iwe.u.mode = IW_MODE_ADHOC;
1258                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1259                                                   &iwe, IW_EV_UINT_LEN);
1260         }
1261
1262         buf = kmalloc(30, GFP_ATOMIC);
1263         if (buf) {
1264                 memset(&iwe, 0, sizeof(iwe));
1265                 iwe.cmd = IWEVCUSTOM;
1266                 sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->pub.tsf));
1267                 iwe.u.data.length = strlen(buf);
1268                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1269                                                   &iwe, buf);
1270                 memset(&iwe, 0, sizeof(iwe));
1271                 iwe.cmd = IWEVCUSTOM;
1272                 sprintf(buf, " Last beacon: %ums ago",
1273                         elapsed_jiffies_msecs(bss->ts));
1274                 iwe.u.data.length = strlen(buf);
1275                 current_ev = iwe_stream_add_point(info, current_ev,
1276                                                   end_buf, &iwe, buf);
1277                 kfree(buf);
1278         }
1279
1280         ieee80211_scan_add_ies(info, &bss->pub, &current_ev, end_buf);
1281
1282         return current_ev;
1283 }
1284
1285
1286 static int ieee80211_scan_results(struct cfg80211_registered_device *dev,
1287                                   struct iw_request_info *info,
1288                                   char *buf, size_t len)
1289 {
1290         char *current_ev = buf;
1291         char *end_buf = buf + len;
1292         struct cfg80211_internal_bss *bss;
1293
1294         spin_lock_bh(&dev->bss_lock);
1295         cfg80211_bss_expire(dev);
1296
1297         list_for_each_entry(bss, &dev->bss_list, list) {
1298                 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
1299                         spin_unlock_bh(&dev->bss_lock);
1300                         return -E2BIG;
1301                 }
1302                 current_ev = ieee80211_bss(&dev->wiphy, info, bss,
1303                                            current_ev, end_buf);
1304         }
1305         spin_unlock_bh(&dev->bss_lock);
1306         return current_ev - buf;
1307 }
1308
1309
1310 int cfg80211_wext_giwscan(struct net_device *dev,
1311                           struct iw_request_info *info,
1312                           struct iw_point *data, char *extra)
1313 {
1314         struct cfg80211_registered_device *rdev;
1315         int res;
1316
1317         if (!netif_running(dev))
1318                 return -ENETDOWN;
1319
1320         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1321
1322         if (IS_ERR(rdev))
1323                 return PTR_ERR(rdev);
1324
1325         if (rdev->scan_req) {
1326                 res = -EAGAIN;
1327                 goto out;
1328         }
1329
1330         res = ieee80211_scan_results(rdev, info, extra, data->length);
1331         data->length = 0;
1332         if (res >= 0) {
1333                 data->length = res;
1334                 res = 0;
1335         }
1336
1337  out:
1338         cfg80211_unlock_rdev(rdev);
1339         return res;
1340 }
1341 EXPORT_SYMBOL_GPL(cfg80211_wext_giwscan);
1342 #endif