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                 /* XXX: workaround */
 368                 res->hold = found->hold;
 369                 kref_put(&found->ref, bss_release);
 370                 found = res;
 371         } else if (found) {
 372                 kref_get(&found->ref);
 373                 found->pub.beacon_interval = res->pub.beacon_interval;
 374                 found->pub.tsf = res->pub.tsf;
 375                 found->pub.signal = res->pub.signal;
 376                 found->pub.capability = res->pub.capability;
 377                 found->ts = res->ts;
 378                 kref_put(&res->ref, bss_release);
 379         } else {
 380                 /* this "consumes" the reference */
 381                 list_add_tail(&res->list, &dev->bss_list);
 382                 rb_insert_bss(dev, res);
 383                 found = res;
 384         }
 385
 386         dev->bss_generation++;
 387         spin_unlock_bh(&dev->bss_lock);
 388
 389         kref_get(&found->ref);
 390         return found;
 391 }
 392
 393 struct cfg80211_bss *
 394 cfg80211_inform_bss_frame(struct wiphy *wiphy,
 395                           struct ieee80211_channel *channel,
 396                           struct ieee80211_mgmt *mgmt, size_t len,
 397                           s32 signal, gfp_t gfp)
 398 {
 399         struct cfg80211_internal_bss *res;
 400         size_t ielen = len - offsetof(struct ieee80211_mgmt,
 401                                       u.probe_resp.variable);
 402         bool overwrite;
 403         size_t privsz = wiphy->bss_priv_size;
 404
 405         if (WARN_ON(wiphy->signal_type == NL80211_BSS_SIGNAL_UNSPEC &&
 406                     (signal < 0 || signal > 100)))
 407                 return NULL;
 408
 409         if (WARN_ON(!mgmt || !wiphy ||
 410                     len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
 411                 return NULL;
 412
 413         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
 414         if (!res)
 415                 return NULL;
 416
 417         memcpy(res->pub.bssid, mgmt->bssid, ETH_ALEN);
 418         res->pub.channel = channel;
 419         res->pub.signal = signal;
 420         res->pub.tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
 421         res->pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
 422         res->pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
 423         /* point to after the private area */
 424         res->pub.information_elements = (u8 *)res + sizeof(*res) + privsz;
 425         memcpy(res->pub.information_elements, mgmt->u.probe_resp.variable, ielen);
 426         res->pub.len_information_elements = ielen;
 427
 428         kref_init(&res->ref);
 429
 430         overwrite = ieee80211_is_probe_resp(mgmt->frame_control);
 431
 432         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res, overwrite);
 433         if (!res)
 434                 return NULL;
 435
 436         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 437                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 438
 439         /* cfg80211_bss_update gives us a referenced result */
 440         return &res->pub;
 441 }
 442 EXPORT_SYMBOL(cfg80211_inform_bss_frame);
 443
 444 void cfg80211_put_bss(struct cfg80211_bss *pub)
 445 {
 446         struct cfg80211_internal_bss *bss;
 447
 448         if (!pub)
 449                 return;
 450
 451         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 452         kref_put(&bss->ref, bss_release);
 453 }
 454 EXPORT_SYMBOL(cfg80211_put_bss);
 455
 456 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
 457 {
 458         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 459         struct cfg80211_internal_bss *bss;
 460
 461         if (WARN_ON(!pub))
 462                 return;
 463
 464         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 465
 466         spin_lock_bh(&dev->bss_lock);
 467
 468         list_del(&bss->list);
 469         rb_erase(&bss->rbn, &dev->bss_tree);
 470
 471         spin_unlock_bh(&dev->bss_lock);
 472
 473         kref_put(&bss->ref, bss_release);
 474 }
 475 EXPORT_SYMBOL(cfg80211_unlink_bss);
 476
 477 void cfg80211_hold_bss(struct cfg80211_bss *pub)
 478 {
 479         struct cfg80211_internal_bss *bss;
 480
 481         if (!pub)
 482                 return;
 483
 484         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 485         bss->hold = true;
 486 }
 487 EXPORT_SYMBOL(cfg80211_hold_bss);
 488
 489 void cfg80211_unhold_bss(struct cfg80211_bss *pub)
 490 {
 491         struct cfg80211_internal_bss *bss;
 492
 493         if (!pub)
 494                 return;
 495
 496         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 497         bss->hold = false;
 498 }
 499 EXPORT_SYMBOL(cfg80211_unhold_bss);
 500
 501 #ifdef CONFIG_WIRELESS_EXT
 502 int cfg80211_wext_siwscan(struct net_device *dev,
 503                           struct iw_request_info *info,
 504                           union iwreq_data *wrqu, char *extra)
 505 {
 506         struct cfg80211_registered_device *rdev;
 507         struct wiphy *wiphy;
 508         struct iw_scan_req *wreq = NULL;
 509         struct cfg80211_scan_request *creq;
 510         int i, err, n_channels = 0;
 511         enum ieee80211_band band;
 512
 513         if (!netif_running(dev))
 514                 return -ENETDOWN;
 515
 516         rdev = cfg80211_get_dev_from_ifindex(dev->ifindex);
 517
 518         if (IS_ERR(rdev))
 519                 return PTR_ERR(rdev);
 520
 521         if (rdev->scan_req) {
 522                 err = -EBUSY;
 523                 goto out;
 524         }
 525
 526         wiphy = &rdev->wiphy;
 527
 528         for (band = 0; band < IEEE80211_NUM_BANDS; band++)
 529                 if (wiphy->bands[band])
 530                         n_channels += wiphy->bands[band]->n_channels;
 531
 532         creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
 533                        n_channels * sizeof(void *),
 534                        GFP_ATOMIC);
 535         if (!creq) {
 536                 err = -ENOMEM;
 537                 goto out;
 538         }
 539
 540         creq->wiphy = wiphy;
 541         creq->ifidx = dev->ifindex;
 542         creq->ssids = (void *)(creq + 1);
 543         creq->channels = (void *)(creq->ssids + 1);
 544         creq->n_channels = n_channels;
 545         creq->n_ssids = 1;
 546
 547         /* all channels */
 548         i = 0;
 549         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
 550                 int j;
 551                 if (!wiphy->bands[band])
 552                         continue;
 553                 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
 554                         creq->channels[i] = &wiphy->bands[band]->channels[j];
 555                         i++;
 556                 }
 557         }
 558
 559         /* translate scan request */
 560         if (wrqu->data.length == sizeof(struct iw_scan_req)) {
 561                 wreq = (struct iw_scan_req *)extra;
 562
 563                 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
 564                         if (wreq->essid_len > IEEE80211_MAX_SSID_LEN)
 565                                 return -EINVAL;
 566                         memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
 567                         creq->ssids[0].ssid_len = wreq->essid_len;
 568                 }
 569                 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
 570                         creq->n_ssids = 0;
 571         }
 572
 573         rdev->scan_req = creq;
 574         err = rdev->ops->scan(wiphy, dev, creq);
 575         if (err) {
 576                 rdev->scan_req = NULL;
 577                 kfree(creq);
 578         }
 579  out:
 580         cfg80211_put_dev(rdev);
 581         return err;
 582 }
 583 EXPORT_SYMBOL(cfg80211_wext_siwscan);
 584
 585 static void ieee80211_scan_add_ies(struct iw_request_info *info,
 586                                    struct cfg80211_bss *bss,
 587                                    char **current_ev, char *end_buf)
 588 {
 589         u8 *pos, *end, *next;
 590         struct iw_event iwe;
 591
 592         if (!bss->information_elements ||
 593             !bss->len_information_elements)
 594                 return;
 595
 596         /*
 597          * If needed, fragment the IEs buffer (at IE boundaries) into short
 598          * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
 599          */
 600         pos = bss->information_elements;
 601         end = pos + bss->len_information_elements;
 602
 603         while (end - pos > IW_GENERIC_IE_MAX) {
 604                 next = pos + 2 + pos[1];
 605                 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
 606                         next = next + 2 + next[1];
 607
 608                 memset(&iwe, 0, sizeof(iwe));
 609                 iwe.cmd = IWEVGENIE;
 610                 iwe.u.data.length = next - pos;
 611                 *current_ev = iwe_stream_add_point(info, *current_ev,
 612                                                    end_buf, &iwe, pos);
 613
 614                 pos = next;
 615         }
 616
 617         if (end > pos) {
 618                 memset(&iwe, 0, sizeof(iwe));
 619                 iwe.cmd = IWEVGENIE;
 620                 iwe.u.data.length = end - pos;
 621                 *current_ev = iwe_stream_add_point(info, *current_ev,
 622                                                    end_buf, &iwe, pos);
 623         }
 624 }
 625
 626 static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
 627 {
 628         unsigned long end = jiffies;
 629
 630         if (end >= start)
 631                 return jiffies_to_msecs(end - start);
 632
 633         return jiffies_to_msecs(end + (MAX_JIFFY_OFFSET - start) + 1);
 634 }
 635
 636 static char *
 637 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
 638               struct cfg80211_internal_bss *bss, char *current_ev,
 639               char *end_buf)
 640 {
 641         struct iw_event iwe;
 642         u8 *buf, *cfg, *p;
 643         u8 *ie = bss->pub.information_elements;
 644         int rem = bss->pub.len_information_elements, i, sig;
 645         bool ismesh = false;
 646
 647         memset(&iwe, 0, sizeof(iwe));
 648         iwe.cmd = SIOCGIWAP;
 649         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
 650         memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
 651         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
 652                                           IW_EV_ADDR_LEN);
 653
 654         memset(&iwe, 0, sizeof(iwe));
 655         iwe.cmd = SIOCGIWFREQ;
 656         iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
 657         iwe.u.freq.e = 0;
 658         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
 659                                           IW_EV_FREQ_LEN);
 660
 661         memset(&iwe, 0, sizeof(iwe));
 662         iwe.cmd = SIOCGIWFREQ;
 663         iwe.u.freq.m = bss->pub.channel->center_freq;
 664         iwe.u.freq.e = 6;
 665         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
 666                                           IW_EV_FREQ_LEN);
 667
 668         if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
 669                 memset(&iwe, 0, sizeof(iwe));
 670                 iwe.cmd = IWEVQUAL;
 671                 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
 672                                      IW_QUAL_NOISE_INVALID |
 673                                      IW_QUAL_QUAL_UPDATED;
 674                 switch (wiphy->signal_type) {
 675                 case CFG80211_SIGNAL_TYPE_MBM:
 676                         sig = bss->pub.signal / 100;
 677                         iwe.u.qual.level = sig;
 678                         iwe.u.qual.updated |= IW_QUAL_DBM;
 679                         if (sig < -110)         /* rather bad */
 680                                 sig = -110;
 681                         else if (sig > -40)     /* perfect */
 682                                 sig = -40;
 683                         /* will give a range of 0 .. 70 */
 684                         iwe.u.qual.qual = sig + 110;
 685                         break;
 686                 case CFG80211_SIGNAL_TYPE_UNSPEC:
 687                         iwe.u.qual.level = bss->pub.signal;
 688                         /* will give range 0 .. 100 */
 689                         iwe.u.qual.qual = bss->pub.signal;
 690                         break;
 691                 default:
 692                         /* not reached */
 693                         break;
 694                 }
 695                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
 696                                                   &iwe, IW_EV_QUAL_LEN);
 697         }
 698
 699         memset(&iwe, 0, sizeof(iwe));
 700         iwe.cmd = SIOCGIWENCODE;
 701         if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
 702                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
 703         else
 704                 iwe.u.data.flags = IW_ENCODE_DISABLED;
 705         iwe.u.data.length = 0;
 706         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
 707                                           &iwe, "");
 708
 709         while (rem >= 2) {
 710                 /* invalid data */
 711                 if (ie[1] > rem - 2)
 712                         break;
 713
 714                 switch (ie[0]) {
 715                 case WLAN_EID_SSID:
 716                         memset(&iwe, 0, sizeof(iwe));
 717                         iwe.cmd = SIOCGIWESSID;
 718                         iwe.u.data.length = ie[1];
 719                         iwe.u.data.flags = 1;
 720                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
 721                                                           &iwe, ie + 2);
 722                         break;
 723                 case WLAN_EID_MESH_ID:
 724                         memset(&iwe, 0, sizeof(iwe));
 725                         iwe.cmd = SIOCGIWESSID;
 726                         iwe.u.data.length = ie[1];
 727                         iwe.u.data.flags = 1;
 728                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
 729                                                           &iwe, ie + 2);
 730                         break;
 731                 case WLAN_EID_MESH_CONFIG:
 732                         ismesh = true;
 733                         if (ie[1] != IEEE80211_MESH_CONFIG_LEN)
 734                                 break;
 735                         buf = kmalloc(50, GFP_ATOMIC);
 736                         if (!buf)
 737                                 break;
 738                         cfg = ie + 2;
 739                         memset(&iwe, 0, sizeof(iwe));
 740                         iwe.cmd = IWEVCUSTOM;
 741                         sprintf(buf, "Mesh network (version %d)", cfg[0]);
 742                         iwe.u.data.length = strlen(buf);
 743                         current_ev = iwe_stream_add_point(info, current_ev,
 744                                                           end_buf,
 745                                                           &iwe, buf);
 746                         sprintf(buf, "Path Selection Protocol ID: "
 747                                 "0x%02X%02X%02X%02X", cfg[1], cfg[2], cfg[3],
 748                                                         cfg[4]);
 749                         iwe.u.data.length = strlen(buf);
 750                         current_ev = iwe_stream_add_point(info, current_ev,
 751                                                           end_buf,
 752                                                           &iwe, buf);
 753                         sprintf(buf, "Path Selection Metric ID: "
 754                                 "0x%02X%02X%02X%02X", cfg[5], cfg[6], cfg[7],
 755                                                         cfg[8]);
 756                         iwe.u.data.length = strlen(buf);
 757                         current_ev = iwe_stream_add_point(info, current_ev,
 758                                                           end_buf,
 759                                                           &iwe, buf);
 760                         sprintf(buf, "Congestion Control Mode ID: "
 761                                 "0x%02X%02X%02X%02X", cfg[9], cfg[10],
 762                                                         cfg[11], cfg[12]);
 763                         iwe.u.data.length = strlen(buf);
 764                         current_ev = iwe_stream_add_point(info, current_ev,
 765                                                           end_buf,
 766                                                           &iwe, buf);
 767                         sprintf(buf, "Channel Precedence: "
 768                                 "0x%02X%02X%02X%02X", cfg[13], cfg[14],
 769                                                         cfg[15], cfg[16]);
 770                         iwe.u.data.length = strlen(buf);
 771                         current_ev = iwe_stream_add_point(info, current_ev,
 772                                                           end_buf,
 773                                                           &iwe, buf);
 774                         kfree(buf);
 775                         break;
 776                 case WLAN_EID_SUPP_RATES:
 777                 case WLAN_EID_EXT_SUPP_RATES:
 778                         /* display all supported rates in readable format */
 779                         p = current_ev + iwe_stream_lcp_len(info);
 780
 781                         memset(&iwe, 0, sizeof(iwe));
 782                         iwe.cmd = SIOCGIWRATE;
 783                         /* Those two flags are ignored... */
 784                         iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
 785
 786                         for (i = 0; i < ie[1]; i++) {
 787                                 iwe.u.bitrate.value =
 788                                         ((ie[i + 2] & 0x7f) * 500000);
 789                                 p = iwe_stream_add_value(info, current_ev, p,
 790                                                 end_buf, &iwe, IW_EV_PARAM_LEN);
 791                         }
 792                         current_ev = p;
 793                         break;
 794                 }
 795                 rem -= ie[1] + 2;
 796                 ie += ie[1] + 2;
 797         }
 798
 799         if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS)
 800             || ismesh) {
 801                 memset(&iwe, 0, sizeof(iwe));
 802                 iwe.cmd = SIOCGIWMODE;
 803                 if (ismesh)
 804                         iwe.u.mode = IW_MODE_MESH;
 805                 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
 806                         iwe.u.mode = IW_MODE_MASTER;
 807                 else
 808                         iwe.u.mode = IW_MODE_ADHOC;
 809                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
 810                                                   &iwe, IW_EV_UINT_LEN);
 811         }
 812
 813         buf = kmalloc(30, GFP_ATOMIC);
 814         if (buf) {
 815                 memset(&iwe, 0, sizeof(iwe));
 816                 iwe.cmd = IWEVCUSTOM;
 817                 sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->pub.tsf));
 818                 iwe.u.data.length = strlen(buf);
 819                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
 820                                                   &iwe, buf);
 821                 memset(&iwe, 0, sizeof(iwe));
 822                 iwe.cmd = IWEVCUSTOM;
 823                 sprintf(buf, " Last beacon: %ums ago",
 824                         elapsed_jiffies_msecs(bss->ts));
 825                 iwe.u.data.length = strlen(buf);
 826                 current_ev = iwe_stream_add_point(info, current_ev,
 827                                                   end_buf, &iwe, buf);
 828                 kfree(buf);
 829         }
 830
 831         ieee80211_scan_add_ies(info, &bss->pub, &current_ev, end_buf);
 832
 833         return current_ev;
 834 }
 835
 836
 837 static int ieee80211_scan_results(struct cfg80211_registered_device *dev,
 838                                   struct iw_request_info *info,
 839                                   char *buf, size_t len)
 840 {
 841         char *current_ev = buf;
 842         char *end_buf = buf + len;
 843         struct cfg80211_internal_bss *bss;
 844
 845         spin_lock_bh(&dev->bss_lock);
 846         cfg80211_bss_expire(dev);
 847
 848         list_for_each_entry(bss, &dev->bss_list, list) {
 849                 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
 850                         spin_unlock_bh(&dev->bss_lock);
 851                         return -E2BIG;
 852                 }
 853                 current_ev = ieee80211_bss(&dev->wiphy, info, bss,
 854                                            current_ev, end_buf);
 855         }
 856         spin_unlock_bh(&dev->bss_lock);
 857         return current_ev - buf;
 858 }
 859
 860
 861 int cfg80211_wext_giwscan(struct net_device *dev,
 862                           struct iw_request_info *info,
 863                           struct iw_point *data, char *extra)
 864 {
 865         struct cfg80211_registered_device *rdev;
 866         int res;
 867
 868         if (!netif_running(dev))
 869                 return -ENETDOWN;
 870
 871         rdev = cfg80211_get_dev_from_ifindex(dev->ifindex);
 872
 873         if (IS_ERR(rdev))
 874                 return PTR_ERR(rdev);
 875
 876         if (rdev->scan_req) {
 877                 res = -EAGAIN;
 878                 goto out;
 879         }
 880
 881         res = ieee80211_scan_results(rdev, info, extra, data->length);
 882         data->length = 0;
 883         if (res >= 0) {
 884                 data->length = res;
 885                 res = 0;
 886         }
 887
 888  out:
 889         cfg80211_put_dev(rdev);
 890         return res;
 891 }
 892 EXPORT_SYMBOL(cfg80211_wext_giwscan);
 893 #endif