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/module.h>
   8 #include <linux/netdevice.h>
   9 #include <linux/wireless.h>
  10 #include <linux/nl80211.h>
  11 #include <linux/etherdevice.h>
  12 #include <net/arp.h>
  13 #include <net/cfg80211.h>
  14 #include <net/iw_handler.h>
  15 #include "core.h"
  16 #include "nl80211.h"
  17
  18 #define IEEE80211_SCAN_RESULT_EXPIRE    (10 * HZ)
  19
  20 void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
  21 {
  22         struct net_device *dev;
  23 #ifdef CONFIG_WIRELESS_EXT
  24         union iwreq_data wrqu;
  25 #endif
  26
  27         dev = dev_get_by_index(&init_net, request->ifidx);
  28         if (!dev)
  29                 goto out;
  30
  31         WARN_ON(request != wiphy_to_dev(request->wiphy)->scan_req);
  32         wiphy_to_dev(request->wiphy)->scan_req = NULL;
  33
  34         if (aborted)
  35                 nl80211_send_scan_aborted(wiphy_to_dev(request->wiphy), dev);
  36         else
  37                 nl80211_send_scan_done(wiphy_to_dev(request->wiphy), dev);
  38
  39 #ifdef CONFIG_WIRELESS_EXT
  40         if (!aborted) {
  41                 memset(&wrqu, 0, sizeof(wrqu));
  42
  43                 wireless_send_event(dev, SIOCGIWSCAN, &wrqu, NULL);
  44         }
  45 #endif
  46
  47         dev_put(dev);
  48
  49  out:
  50         kfree(request);
  51 }
  52 EXPORT_SYMBOL(cfg80211_scan_done);
  53
  54 static void bss_release(struct kref *ref)
  55 {
  56         struct cfg80211_internal_bss *bss;
  57
  58         bss = container_of(ref, struct cfg80211_internal_bss, ref);
  59         if (bss->pub.free_priv)
  60                 bss->pub.free_priv(&bss->pub);
  61         kfree(bss);
  62 }
  63
  64 /* must hold dev->bss_lock! */
  65 void cfg80211_bss_age(struct cfg80211_registered_device *dev,
  66                       unsigned long age_secs)
  67 {
  68         struct cfg80211_internal_bss *bss;
  69         unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
  70
  71         list_for_each_entry(bss, &dev->bss_list, list) {
  72                 bss->ts -= age_jiffies;
  73         }
  74 }
  75
  76 /* must hold dev->bss_lock! */
  77 void cfg80211_bss_expire(struct cfg80211_registered_device *dev)
  78 {
  79         struct cfg80211_internal_bss *bss, *tmp;
  80         bool expired = false;
  81
  82         list_for_each_entry_safe(bss, tmp, &dev->bss_list, list) {
  83                 if (bss->hold ||
  84                     !time_after(jiffies, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE))
  85                         continue;
  86                 list_del(&bss->list);
  87                 rb_erase(&bss->rbn, &dev->bss_tree);
  88                 kref_put(&bss->ref, bss_release);
  89                 expired = true;
  90         }
  91
  92         if (expired)
  93                 dev->bss_generation++;
  94 }
  95
  96 static u8 *find_ie(u8 num, u8 *ies, size_t len)
  97 {
  98         while (len > 2 && ies[0] != num) {
  99                 len -= ies[1] + 2;
 100                 ies += ies[1] + 2;
 101         }
 102         if (len < 2)
 103                 return NULL;
 104         if (len < 2 + ies[1])
 105                 return NULL;
 106         return ies;
 107 }
 108
 109 static int cmp_ies(u8 num, u8 *ies1, size_t len1, u8 *ies2, size_t len2)
 110 {
 111         const u8 *ie1 = find_ie(num, ies1, len1);
 112         const u8 *ie2 = find_ie(num, ies2, len2);
 113         int r;
 114
 115         if (!ie1 && !ie2)
 116                 return 0;
 117         if (!ie1)
 118                 return -1;
 119
 120         r = memcmp(ie1 + 2, ie2 + 2, min(ie1[1], ie2[1]));
 121         if (r == 0 && ie1[1] != ie2[1])
 122                 return ie2[1] - ie1[1];
 123         return r;
 124 }
 125
 126 static bool is_bss(struct cfg80211_bss *a,
 127                    const u8 *bssid,
 128                    const u8 *ssid, size_t ssid_len)
 129 {
 130         const u8 *ssidie;
 131
 132         if (bssid && compare_ether_addr(a->bssid, bssid))
 133                 return false;
 134
 135         if (!ssid)
 136                 return true;
 137
 138         ssidie = find_ie(WLAN_EID_SSID,
 139                          a->information_elements,
 140                          a->len_information_elements);
 141         if (!ssidie)
 142                 return false;
 143         if (ssidie[1] != ssid_len)
 144                 return false;
 145         return memcmp(ssidie + 2, ssid, ssid_len) == 0;
 146 }
 147
 148 static bool is_mesh(struct cfg80211_bss *a,
 149                     const u8 *meshid, size_t meshidlen,
 150                     const u8 *meshcfg)
 151 {
 152         const u8 *ie;
 153
 154         if (!is_zero_ether_addr(a->bssid))
 155                 return false;
 156
 157         ie = find_ie(WLAN_EID_MESH_ID,
 158                      a->information_elements,
 159                      a->len_information_elements);
 160         if (!ie)
 161                 return false;
 162         if (ie[1] != meshidlen)
 163                 return false;
 164         if (memcmp(ie + 2, meshid, meshidlen))
 165                 return false;
 166
 167         ie = find_ie(WLAN_EID_MESH_CONFIG,
 168                      a->information_elements,
 169                      a->len_information_elements);
 170         if (ie[1] != IEEE80211_MESH_CONFIG_LEN)
 171                 return false;
 172
 173         /*
 174          * Ignore mesh capability (last two bytes of the IE) when
 175          * comparing since that may differ between stations taking
 176          * part in the same mesh.
 177          */
 178         return memcmp(ie + 2, meshcfg, IEEE80211_MESH_CONFIG_LEN - 2) == 0;
 179 }
 180
 181 static int cmp_bss(struct cfg80211_bss *a,
 182                    struct cfg80211_bss *b)
 183 {
 184         int r;
 185
 186         if (a->channel != b->channel)
 187                 return b->channel->center_freq - a->channel->center_freq;
 188
 189         r = memcmp(a->bssid, b->bssid, ETH_ALEN);
 190         if (r)
 191                 return r;
 192
 193         if (is_zero_ether_addr(a->bssid)) {
 194                 r = cmp_ies(WLAN_EID_MESH_ID,
 195                             a->information_elements,
 196                             a->len_information_elements,
 197                             b->information_elements,
 198                             b->len_information_elements);
 199                 if (r)
 200                         return r;
 201                 return cmp_ies(WLAN_EID_MESH_CONFIG,
 202                                a->information_elements,
 203                                a->len_information_elements,
 204                                b->information_elements,
 205                                b->len_information_elements);
 206         }
 207
 208         return cmp_ies(WLAN_EID_SSID,
 209                        a->information_elements,
 210                        a->len_information_elements,
 211                        b->information_elements,
 212                        b->len_information_elements);
 213 }
 214
 215 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
 216                                       struct ieee80211_channel *channel,
 217                                       const u8 *bssid,
 218                                       const u8 *ssid, size_t ssid_len,
 219                                       u16 capa_mask, u16 capa_val)
 220 {
 221         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 222         struct cfg80211_internal_bss *bss, *res = NULL;
 223
 224         spin_lock_bh(&dev->bss_lock);
 225
 226         list_for_each_entry(bss, &dev->bss_list, list) {
 227                 if ((bss->pub.capability & capa_mask) != capa_val)
 228                         continue;
 229                 if (channel && bss->pub.channel != channel)
 230                         continue;
 231                 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
 232                         res = bss;
 233                         kref_get(&res->ref);
 234                         break;
 235                 }
 236         }
 237
 238         spin_unlock_bh(&dev->bss_lock);
 239         if (!res)
 240                 return NULL;
 241         return &res->pub;
 242 }
 243 EXPORT_SYMBOL(cfg80211_get_bss);
 244
 245 struct cfg80211_bss *cfg80211_get_mesh(struct wiphy *wiphy,
 246                                        struct ieee80211_channel *channel,
 247                                        const u8 *meshid, size_t meshidlen,
 248                                        const u8 *meshcfg)
 249 {
 250         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 251         struct cfg80211_internal_bss *bss, *res = NULL;
 252
 253         spin_lock_bh(&dev->bss_lock);
 254
 255         list_for_each_entry(bss, &dev->bss_list, list) {
 256                 if (channel && bss->pub.channel != channel)
 257                         continue;
 258                 if (is_mesh(&bss->pub, meshid, meshidlen, meshcfg)) {
 259                         res = bss;
 260                         kref_get(&res->ref);
 261                         break;
 262                 }
 263         }
 264
 265         spin_unlock_bh(&dev->bss_lock);
 266         if (!res)
 267                 return NULL;
 268         return &res->pub;
 269 }
 270 EXPORT_SYMBOL(cfg80211_get_mesh);
 271
 272
 273 static void rb_insert_bss(struct cfg80211_registered_device *dev,
 274                           struct cfg80211_internal_bss *bss)
 275 {
 276         struct rb_node **p = &dev->bss_tree.rb_node;
 277         struct rb_node *parent = NULL;
 278         struct cfg80211_internal_bss *tbss;
 279         int cmp;
 280
 281         while (*p) {
 282                 parent = *p;
 283                 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
 284
 285                 cmp = cmp_bss(&bss->pub, &tbss->pub);
 286
 287                 if (WARN_ON(!cmp)) {
 288                         /* will sort of leak this BSS */
 289                         return;
 290                 }
 291
 292                 if (cmp < 0)
 293                         p = &(*p)->rb_left;
 294                 else
 295                         p = &(*p)->rb_right;
 296         }
 297
 298         rb_link_node(&bss->rbn, parent, p);
 299         rb_insert_color(&bss->rbn, &dev->bss_tree);
 300 }
 301
 302 static struct cfg80211_internal_bss *
 303 rb_find_bss(struct cfg80211_registered_device *dev,
 304             struct cfg80211_internal_bss *res)
 305 {
 306         struct rb_node *n = dev->bss_tree.rb_node;
 307         struct cfg80211_internal_bss *bss;
 308         int r;
 309
 310         while (n) {
 311                 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
 312                 r = cmp_bss(&res->pub, &bss->pub);
 313
 314                 if (r == 0)
 315                         return bss;
 316                 else if (r < 0)
 317                         n = n->rb_left;
 318                 else
 319                         n = n->rb_right;
 320         }
 321
 322         return NULL;
 323 }
 324
 325 static struct cfg80211_internal_bss *
 326 cfg80211_bss_update(struct cfg80211_registered_device *dev,
 327                     struct cfg80211_internal_bss *res,
 328                     bool overwrite)
 329 {
 330         struct cfg80211_internal_bss *found = NULL;
 331         const u8 *meshid, *meshcfg;
 332
 333         /*
 334          * The reference to "res" is donated to this function.
 335          */
 336
 337         if (WARN_ON(!res->pub.channel)) {
 338                 kref_put(&res->ref, bss_release);
 339                 return NULL;
 340         }
 341
 342         res->ts = jiffies;
 343
 344         if (is_zero_ether_addr(res->pub.bssid)) {
 345                 /* must be mesh, verify */
 346                 meshid = find_ie(WLAN_EID_MESH_ID, res->pub.information_elements,
 347                                  res->pub.len_information_elements);
 348                 meshcfg = find_ie(WLAN_EID_MESH_CONFIG,
 349                                   res->pub.information_elements,
 350                                   res->pub.len_information_elements);
 351                 if (!meshid || !meshcfg ||
 352                     meshcfg[1] != IEEE80211_MESH_CONFIG_LEN) {
 353                         /* bogus mesh */
 354                         kref_put(&res->ref, bss_release);
 355                         return NULL;
 356                 }
 357         }
 358
 359         spin_lock_bh(&dev->bss_lock);
 360
 361         found = rb_find_bss(dev, res);
 362
 363         if (found && overwrite) {
 364                 list_replace(&found->list, &res->list);
 365                 rb_replace_node(&found->rbn, &res->rbn,
 366                                 &dev->bss_tree);
 367                 kref_put(&found->ref, bss_release);
 368                 found = res;
 369         } else if (found) {
 370                 kref_get(&found->ref);
 371                 found->pub.beacon_interval = res->pub.beacon_interval;
 372                 found->pub.tsf = res->pub.tsf;
 373                 found->pub.signal = res->pub.signal;
 374                 found->pub.capability = res->pub.capability;
 375                 found->ts = res->ts;
 376                 kref_put(&res->ref, bss_release);
 377         } else {
 378                 /* this "consumes" the reference */
 379                 list_add_tail(&res->list, &dev->bss_list);
 380                 rb_insert_bss(dev, res);
 381                 found = res;
 382         }
 383
 384         dev->bss_generation++;
 385         spin_unlock_bh(&dev->bss_lock);
 386
 387         kref_get(&found->ref);
 388         return found;
 389 }
 390
 391 struct cfg80211_bss *
 392 cfg80211_inform_bss_frame(struct wiphy *wiphy,
 393                           struct ieee80211_channel *channel,
 394                           struct ieee80211_mgmt *mgmt, size_t len,
 395                           s32 signal, gfp_t gfp)
 396 {
 397         struct cfg80211_internal_bss *res;
 398         size_t ielen = len - offsetof(struct ieee80211_mgmt,
 399                                       u.probe_resp.variable);
 400         bool overwrite;
 401         size_t privsz = wiphy->bss_priv_size;
 402
 403         if (WARN_ON(wiphy->signal_type == NL80211_BSS_SIGNAL_UNSPEC &&
 404                     (signal < 0 || signal > 100)))
 405                 return NULL;
 406
 407         if (WARN_ON(!mgmt || !wiphy ||
 408                     len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
 409                 return NULL;
 410
 411         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
 412         if (!res)
 413                 return NULL;
 414
 415         memcpy(res->pub.bssid, mgmt->bssid, ETH_ALEN);
 416         res->pub.channel = channel;
 417         res->pub.signal = signal;
 418         res->pub.tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
 419         res->pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
 420         res->pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
 421         /* point to after the private area */
 422         res->pub.information_elements = (u8 *)res + sizeof(*res) + privsz;
 423         memcpy(res->pub.information_elements, mgmt->u.probe_resp.variable, ielen);
 424         res->pub.len_information_elements = ielen;
 425
 426         kref_init(&res->ref);
 427
 428         overwrite = ieee80211_is_probe_resp(mgmt->frame_control);
 429
 430         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res, overwrite);
 431         if (!res)
 432                 return NULL;
 433
 434         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 435                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 436
 437         /* cfg80211_bss_update gives us a referenced result */
 438         return &res->pub;
 439 }
 440 EXPORT_SYMBOL(cfg80211_inform_bss_frame);
 441
 442 void cfg80211_put_bss(struct cfg80211_bss *pub)
 443 {
 444         struct cfg80211_internal_bss *bss;
 445
 446         if (!pub)
 447                 return;
 448
 449         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 450         kref_put(&bss->ref, bss_release);
 451 }
 452 EXPORT_SYMBOL(cfg80211_put_bss);
 453
 454 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
 455 {
 456         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 457         struct cfg80211_internal_bss *bss;
 458
 459         if (WARN_ON(!pub))
 460                 return;
 461
 462         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 463
 464         spin_lock_bh(&dev->bss_lock);
 465
 466         list_del(&bss->list);
 467         rb_erase(&bss->rbn, &dev->bss_tree);
 468
 469         spin_unlock_bh(&dev->bss_lock);
 470
 471         kref_put(&bss->ref, bss_release);
 472 }
 473 EXPORT_SYMBOL(cfg80211_unlink_bss);
 474
 475 void cfg80211_hold_bss(struct cfg80211_bss *pub)
 476 {
 477         struct cfg80211_internal_bss *bss;
 478
 479         if (!pub)
 480                 return;
 481
 482         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 483         bss->hold = true;
 484 }
 485 EXPORT_SYMBOL(cfg80211_hold_bss);
 486
 487 void cfg80211_unhold_bss(struct cfg80211_bss *pub)
 488 {
 489         struct cfg80211_internal_bss *bss;
 490
 491         if (!pub)
 492                 return;
 493
 494         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 495         bss->hold = false;
 496 }
 497 EXPORT_SYMBOL(cfg80211_unhold_bss);
 498
 499 #ifdef CONFIG_WIRELESS_EXT
 500 int cfg80211_wext_siwscan(struct net_device *dev,
 501                           struct iw_request_info *info,
 502                           union iwreq_data *wrqu, char *extra)
 503 {
 504         struct cfg80211_registered_device *rdev;
 505         struct wiphy *wiphy;
 506         struct iw_scan_req *wreq = NULL;
 507         struct cfg80211_scan_request *creq;
 508         int i, err, n_channels = 0;
 509         enum ieee80211_band band;
 510
 511         if (!netif_running(dev))
 512                 return -ENETDOWN;
 513
 514         rdev = cfg80211_get_dev_from_ifindex(dev->ifindex);
 515
 516         if (IS_ERR(rdev))
 517                 return PTR_ERR(rdev);
 518
 519         if (rdev->scan_req) {
 520                 err = -EBUSY;
 521                 goto out;
 522         }
 523
 524         wiphy = &rdev->wiphy;
 525
 526         for (band = 0; band < IEEE80211_NUM_BANDS; band++)
 527                 if (wiphy->bands[band])
 528                         n_channels += wiphy->bands[band]->n_channels;
 529
 530         creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
 531                        n_channels * sizeof(void *),
 532                        GFP_ATOMIC);
 533         if (!creq) {
 534                 err = -ENOMEM;
 535                 goto out;
 536         }
 537
 538         creq->wiphy = wiphy;
 539         creq->ifidx = dev->ifindex;
 540         creq->ssids = (void *)(creq + 1);
 541         creq->channels = (void *)(creq->ssids + 1);
 542         creq->n_channels = n_channels;
 543         creq->n_ssids = 1;
 544
 545         /* all channels */
 546         i = 0;
 547         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
 548                 int j;
 549                 if (!wiphy->bands[band])
 550                         continue;
 551                 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
 552                         creq->channels[i] = &wiphy->bands[band]->channels[j];
 553                         i++;
 554                 }
 555         }
 556
 557         /* translate scan request */
 558         if (wrqu->data.length == sizeof(struct iw_scan_req)) {
 559                 wreq = (struct iw_scan_req *)extra;
 560
 561                 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
 562                         if (wreq->essid_len > IEEE80211_MAX_SSID_LEN)
 563                                 return -EINVAL;
 564                         memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
 565                         creq->ssids[0].ssid_len = wreq->essid_len;
 566                 }
 567                 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
 568                         creq->n_ssids = 0;
 569         }
 570
 571         rdev->scan_req = creq;
 572         err = rdev->ops->scan(wiphy, dev, creq);
 573         if (err) {
 574                 rdev->scan_req = NULL;
 575                 kfree(creq);
 576         }
 577  out:
 578         cfg80211_put_dev(rdev);
 579         return err;
 580 }
 581 EXPORT_SYMBOL(cfg80211_wext_siwscan);
 582
 583 static void ieee80211_scan_add_ies(struct iw_request_info *info,
 584                                    struct cfg80211_bss *bss,
 585                                    char **current_ev, char *end_buf)
 586 {
 587         u8 *pos, *end, *next;
 588         struct iw_event iwe;
 589
 590         if (!bss->information_elements ||
 591             !bss->len_information_elements)
 592                 return;
 593
 594         /*
 595          * If needed, fragment the IEs buffer (at IE boundaries) into short
 596          * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
 597          */
 598         pos = bss->information_elements;
 599         end = pos + bss->len_information_elements;
 600
 601         while (end - pos > IW_GENERIC_IE_MAX) {
 602                 next = pos + 2 + pos[1];
 603                 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
 604                         next = next + 2 + next[1];
 605
 606                 memset(&iwe, 0, sizeof(iwe));
 607                 iwe.cmd = IWEVGENIE;
 608                 iwe.u.data.length = next - pos;
 609                 *current_ev = iwe_stream_add_point(info, *current_ev,
 610                                                    end_buf, &iwe, pos);
 611
 612                 pos = next;
 613         }
 614
 615         if (end > pos) {
 616                 memset(&iwe, 0, sizeof(iwe));
 617                 iwe.cmd = IWEVGENIE;
 618                 iwe.u.data.length = end - pos;
 619                 *current_ev = iwe_stream_add_point(info, *current_ev,
 620                                                    end_buf, &iwe, pos);
 621         }
 622 }
 623
 624 static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
 625 {
 626         unsigned long end = jiffies;
 627
 628         if (end >= start)
 629                 return jiffies_to_msecs(end - start);
 630
 631         return jiffies_to_msecs(end + (MAX_JIFFY_OFFSET - start) + 1);
 632 }
 633
 634 static char *
 635 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
 636               struct cfg80211_internal_bss *bss, char *current_ev,
 637               char *end_buf)
 638 {
 639         struct iw_event iwe;
 640         u8 *buf, *cfg, *p;
 641         u8 *ie = bss->pub.information_elements;
 642         int rem = bss->pub.len_information_elements, i, sig;
 643         bool ismesh = false;
 644
 645         memset(&iwe, 0, sizeof(iwe));
 646         iwe.cmd = SIOCGIWAP;
 647         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
 648         memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
 649         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
 650                                           IW_EV_ADDR_LEN);
 651
 652         memset(&iwe, 0, sizeof(iwe));
 653         iwe.cmd = SIOCGIWFREQ;
 654         iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
 655         iwe.u.freq.e = 0;
 656         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
 657                                           IW_EV_FREQ_LEN);
 658
 659         memset(&iwe, 0, sizeof(iwe));
 660         iwe.cmd = SIOCGIWFREQ;
 661         iwe.u.freq.m = bss->pub.channel->center_freq;
 662         iwe.u.freq.e = 6;
 663         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
 664                                           IW_EV_FREQ_LEN);
 665
 666         if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
 667                 memset(&iwe, 0, sizeof(iwe));
 668                 iwe.cmd = IWEVQUAL;
 669                 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
 670                                      IW_QUAL_NOISE_INVALID |
 671                                      IW_QUAL_QUAL_UPDATED;
 672                 switch (wiphy->signal_type) {
 673                 case CFG80211_SIGNAL_TYPE_MBM:
 674                         sig = bss->pub.signal / 100;
 675                         iwe.u.qual.level = sig;
 676                         iwe.u.qual.updated |= IW_QUAL_DBM;
 677                         if (sig < -110)         /* rather bad */
 678                                 sig = -110;
 679                         else if (sig > -40)     /* perfect */
 680                                 sig = -40;
 681                         /* will give a range of 0 .. 70 */
 682                         iwe.u.qual.qual = sig + 110;
 683                         break;
 684                 case CFG80211_SIGNAL_TYPE_UNSPEC:
 685                         iwe.u.qual.level = bss->pub.signal;
 686                         /* will give range 0 .. 100 */
 687                         iwe.u.qual.qual = bss->pub.signal;
 688                         break;
 689                 default:
 690                         /* not reached */
 691                         break;
 692                 }
 693                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
 694                                                   &iwe, IW_EV_QUAL_LEN);
 695         }
 696
 697         memset(&iwe, 0, sizeof(iwe));
 698         iwe.cmd = SIOCGIWENCODE;
 699         if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
 700                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
 701         else
 702                 iwe.u.data.flags = IW_ENCODE_DISABLED;
 703         iwe.u.data.length = 0;
 704         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
 705                                           &iwe, "");
 706
 707         while (rem >= 2) {
 708                 /* invalid data */
 709                 if (ie[1] > rem - 2)
 710                         break;
 711
 712                 switch (ie[0]) {
 713                 case WLAN_EID_SSID:
 714                         memset(&iwe, 0, sizeof(iwe));
 715                         iwe.cmd = SIOCGIWESSID;
 716                         iwe.u.data.length = ie[1];
 717                         iwe.u.data.flags = 1;
 718                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
 719                                                           &iwe, ie + 2);
 720                         break;
 721                 case WLAN_EID_MESH_ID:
 722                         memset(&iwe, 0, sizeof(iwe));
 723                         iwe.cmd = SIOCGIWESSID;
 724                         iwe.u.data.length = ie[1];
 725                         iwe.u.data.flags = 1;
 726                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
 727                                                           &iwe, ie + 2);
 728                         break;
 729                 case WLAN_EID_MESH_CONFIG:
 730                         ismesh = true;
 731                         if (ie[1] != IEEE80211_MESH_CONFIG_LEN)
 732                                 break;
 733                         buf = kmalloc(50, GFP_ATOMIC);
 734                         if (!buf)
 735                                 break;
 736                         cfg = ie + 2;
 737                         memset(&iwe, 0, sizeof(iwe));
 738                         iwe.cmd = IWEVCUSTOM;
 739                         sprintf(buf, "Mesh network (version %d)", cfg[0]);
 740                         iwe.u.data.length = strlen(buf);
 741                         current_ev = iwe_stream_add_point(info, current_ev,
 742                                                           end_buf,
 743                                                           &iwe, buf);
 744                         sprintf(buf, "Path Selection Protocol ID: "
 745                                 "0x%02X%02X%02X%02X", cfg[1], cfg[2], cfg[3],
 746                                                         cfg[4]);
 747                         iwe.u.data.length = strlen(buf);
 748                         current_ev = iwe_stream_add_point(info, current_ev,
 749                                                           end_buf,
 750                                                           &iwe, buf);
 751                         sprintf(buf, "Path Selection Metric ID: "
 752                                 "0x%02X%02X%02X%02X", cfg[5], cfg[6], cfg[7],
 753                                                         cfg[8]);
 754                         iwe.u.data.length = strlen(buf);
 755                         current_ev = iwe_stream_add_point(info, current_ev,
 756                                                           end_buf,
 757                                                           &iwe, buf);
 758                         sprintf(buf, "Congestion Control Mode ID: "
 759                                 "0x%02X%02X%02X%02X", cfg[9], cfg[10],
 760                                                         cfg[11], cfg[12]);
 761                         iwe.u.data.length = strlen(buf);
 762                         current_ev = iwe_stream_add_point(info, current_ev,
 763                                                           end_buf,
 764                                                           &iwe, buf);
 765                         sprintf(buf, "Channel Precedence: "
 766                                 "0x%02X%02X%02X%02X", cfg[13], cfg[14],
 767                                                         cfg[15], cfg[16]);
 768                         iwe.u.data.length = strlen(buf);
 769                         current_ev = iwe_stream_add_point(info, current_ev,
 770                                                           end_buf,
 771                                                           &iwe, buf);
 772                         kfree(buf);
 773                         break;
 774                 case WLAN_EID_SUPP_RATES:
 775                 case WLAN_EID_EXT_SUPP_RATES:
 776                         /* display all supported rates in readable format */
 777                         p = current_ev + iwe_stream_lcp_len(info);
 778
 779                         memset(&iwe, 0, sizeof(iwe));
 780                         iwe.cmd = SIOCGIWRATE;
 781                         /* Those two flags are ignored... */
 782                         iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
 783
 784                         for (i = 0; i < ie[1]; i++) {
 785                                 iwe.u.bitrate.value =
 786                                         ((ie[i + 2] & 0x7f) * 500000);
 787                                 p = iwe_stream_add_value(info, current_ev, p,
 788                                                 end_buf, &iwe, IW_EV_PARAM_LEN);
 789                         }
 790                         current_ev = p;
 791                         break;
 792                 }
 793                 rem -= ie[1] + 2;
 794                 ie += ie[1] + 2;
 795         }
 796
 797         if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS)
 798             || ismesh) {
 799                 memset(&iwe, 0, sizeof(iwe));
 800                 iwe.cmd = SIOCGIWMODE;
 801                 if (ismesh)
 802                         iwe.u.mode = IW_MODE_MESH;
 803                 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
 804                         iwe.u.mode = IW_MODE_MASTER;
 805                 else
 806                         iwe.u.mode = IW_MODE_ADHOC;
 807                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
 808                                                   &iwe, IW_EV_UINT_LEN);
 809         }
 810
 811         buf = kmalloc(30, GFP_ATOMIC);
 812         if (buf) {
 813                 memset(&iwe, 0, sizeof(iwe));
 814                 iwe.cmd = IWEVCUSTOM;
 815                 sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->pub.tsf));
 816                 iwe.u.data.length = strlen(buf);
 817                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
 818                                                   &iwe, buf);
 819                 memset(&iwe, 0, sizeof(iwe));
 820                 iwe.cmd = IWEVCUSTOM;
 821                 sprintf(buf, " Last beacon: %ums ago",
 822                         elapsed_jiffies_msecs(bss->ts));
 823                 iwe.u.data.length = strlen(buf);
 824                 current_ev = iwe_stream_add_point(info, current_ev,
 825                                                   end_buf, &iwe, buf);
 826                 kfree(buf);
 827         }
 828
 829         ieee80211_scan_add_ies(info, &bss->pub, &current_ev, end_buf);
 830
 831         return current_ev;
 832 }
 833
 834
 835 static int ieee80211_scan_results(struct cfg80211_registered_device *dev,
 836                                   struct iw_request_info *info,
 837                                   char *buf, size_t len)
 838 {
 839         char *current_ev = buf;
 840         char *end_buf = buf + len;
 841         struct cfg80211_internal_bss *bss;
 842
 843         spin_lock_bh(&dev->bss_lock);
 844         cfg80211_bss_expire(dev);
 845
 846         list_for_each_entry(bss, &dev->bss_list, list) {
 847                 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
 848                         spin_unlock_bh(&dev->bss_lock);
 849                         return -E2BIG;
 850                 }
 851                 current_ev = ieee80211_bss(&dev->wiphy, info, bss,
 852                                            current_ev, end_buf);
 853         }
 854         spin_unlock_bh(&dev->bss_lock);
 855         return current_ev - buf;
 856 }
 857
 858
 859 int cfg80211_wext_giwscan(struct net_device *dev,
 860                           struct iw_request_info *info,
 861                           struct iw_point *data, char *extra)
 862 {
 863         struct cfg80211_registered_device *rdev;
 864         int res;
 865
 866         if (!netif_running(dev))
 867                 return -ENETDOWN;
 868
 869         rdev = cfg80211_get_dev_from_ifindex(dev->ifindex);
 870
 871         if (IS_ERR(rdev))
 872                 return PTR_ERR(rdev);
 873
 874         if (rdev->scan_req) {
 875                 res = -EAGAIN;
 876                 goto out;
 877         }
 878
 879         res = ieee80211_scan_results(rdev, info, extra, data->length);
 880         data->length = 0;
 881         if (res >= 0) {
 882                 data->length = res;
 883                 res = 0;
 884         }
 885
 886  out:
 887         cfg80211_put_dev(rdev);
 888         return res;
 889 }
 890 EXPORT_SYMBOL(cfg80211_wext_giwscan);
 891 #endif