SAFE public projects git trees. - safe/jmp/linux-2.6/blob - net/wireless/scan.c

   1 /*
   2  * cfg80211 scan result handling
   3  *
   4  * Copyright 2008 Johannes Berg <johannes@sipsolutions.net>
   5  */
   6 #include <linux/kernel.h>
   7 #include <linux/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 #include "wext-compat.h"
  18
  19 #define IEEE80211_SCAN_RESULT_EXPIRE    (15 * HZ)
  20
  21 void __cfg80211_scan_done(struct work_struct *wk)
  22 {
  23         struct cfg80211_registered_device *rdev;
  24         struct cfg80211_scan_request *request;
  25         struct net_device *dev;
  26 #ifdef CONFIG_WIRELESS_EXT
  27         union iwreq_data wrqu;
  28 #endif
  29
  30         rdev = container_of(wk, struct cfg80211_registered_device,
  31                             scan_done_wk);
  32
  33         mutex_lock(&rdev->mtx);
  34         request = rdev->scan_req;
  35
  36         dev = request->dev;
  37
  38         /*
  39          * This must be before sending the other events!
  40          * Otherwise, wpa_supplicant gets completely confused with
  41          * wext events.
  42          */
  43         cfg80211_sme_scan_done(dev);
  44
  45         if (request->aborted)
  46                 nl80211_send_scan_aborted(wiphy_to_dev(request->wiphy), dev);
  47         else
  48                 nl80211_send_scan_done(wiphy_to_dev(request->wiphy), dev);
  49
  50 #ifdef CONFIG_WIRELESS_EXT
  51         if (!request->aborted) {
  52                 memset(&wrqu, 0, sizeof(wrqu));
  53
  54                 wireless_send_event(dev, SIOCGIWSCAN, &wrqu, NULL);
  55         }
  56 #endif
  57
  58         dev_put(dev);
  59
  60         cfg80211_unlock_rdev(rdev);
  61         wiphy_to_dev(request->wiphy)->scan_req = NULL;
  62         kfree(request);
  63 }
  64
  65 void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
  66 {
  67         WARN_ON(request != wiphy_to_dev(request->wiphy)->scan_req);
  68
  69         request->aborted = aborted;
  70         schedule_work(&wiphy_to_dev(request->wiphy)->scan_done_wk);
  71 }
  72 EXPORT_SYMBOL(cfg80211_scan_done);
  73
  74 static void bss_release(struct kref *ref)
  75 {
  76         struct cfg80211_internal_bss *bss;
  77
  78         bss = container_of(ref, struct cfg80211_internal_bss, ref);
  79         if (bss->pub.free_priv)
  80                 bss->pub.free_priv(&bss->pub);
  81
  82         if (bss->ies_allocated)
  83                 kfree(bss->pub.information_elements);
  84
  85         BUG_ON(atomic_read(&bss->hold));
  86
  87         kfree(bss);
  88 }
  89
  90 /* must hold dev->bss_lock! */
  91 void cfg80211_bss_age(struct cfg80211_registered_device *dev,
  92                       unsigned long age_secs)
  93 {
  94         struct cfg80211_internal_bss *bss;
  95         unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
  96
  97         list_for_each_entry(bss, &dev->bss_list, list) {
  98                 bss->ts -= age_jiffies;
  99         }
 100 }
 101
 102 /* must hold dev->bss_lock! */
 103 void cfg80211_bss_expire(struct cfg80211_registered_device *dev)
 104 {
 105         struct cfg80211_internal_bss *bss, *tmp;
 106         bool expired = false;
 107
 108         list_for_each_entry_safe(bss, tmp, &dev->bss_list, list) {
 109                 if (atomic_read(&bss->hold))
 110                         continue;
 111                 if (!time_after(jiffies, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE))
 112                         continue;
 113                 list_del(&bss->list);
 114                 rb_erase(&bss->rbn, &dev->bss_tree);
 115                 kref_put(&bss->ref, bss_release);
 116                 expired = true;
 117         }
 118
 119         if (expired)
 120                 dev->bss_generation++;
 121 }
 122
 123 static u8 *find_ie(u8 num, u8 *ies, size_t len)
 124 {
 125         while (len > 2 && ies[0] != num) {
 126                 len -= ies[1] + 2;
 127                 ies += ies[1] + 2;
 128         }
 129         if (len < 2)
 130                 return NULL;
 131         if (len < 2 + ies[1])
 132                 return NULL;
 133         return ies;
 134 }
 135
 136 static int cmp_ies(u8 num, u8 *ies1, size_t len1, u8 *ies2, size_t len2)
 137 {
 138         const u8 *ie1 = find_ie(num, ies1, len1);
 139         const u8 *ie2 = find_ie(num, ies2, len2);
 140         int r;
 141
 142         if (!ie1 && !ie2)
 143                 return 0;
 144         if (!ie1 || !ie2)
 145                 return -1;
 146
 147         r = memcmp(ie1 + 2, ie2 + 2, min(ie1[1], ie2[1]));
 148         if (r == 0 && ie1[1] != ie2[1])
 149                 return ie2[1] - ie1[1];
 150         return r;
 151 }
 152
 153 static bool is_bss(struct cfg80211_bss *a,
 154                    const u8 *bssid,
 155                    const u8 *ssid, size_t ssid_len)
 156 {
 157         const u8 *ssidie;
 158
 159         if (bssid && compare_ether_addr(a->bssid, bssid))
 160                 return false;
 161
 162         if (!ssid)
 163                 return true;
 164
 165         ssidie = find_ie(WLAN_EID_SSID,
 166                          a->information_elements,
 167                          a->len_information_elements);
 168         if (!ssidie)
 169                 return false;
 170         if (ssidie[1] != ssid_len)
 171                 return false;
 172         return memcmp(ssidie + 2, ssid, ssid_len) == 0;
 173 }
 174
 175 static bool is_mesh(struct cfg80211_bss *a,
 176                     const u8 *meshid, size_t meshidlen,
 177                     const u8 *meshcfg)
 178 {
 179         const u8 *ie;
 180
 181         if (!is_zero_ether_addr(a->bssid))
 182                 return false;
 183
 184         ie = find_ie(WLAN_EID_MESH_ID,
 185                      a->information_elements,
 186                      a->len_information_elements);
 187         if (!ie)
 188                 return false;
 189         if (ie[1] != meshidlen)
 190                 return false;
 191         if (memcmp(ie + 2, meshid, meshidlen))
 192                 return false;
 193
 194         ie = find_ie(WLAN_EID_MESH_CONFIG,
 195                      a->information_elements,
 196                      a->len_information_elements);
 197         if (!ie)
 198                 return false;
 199         if (ie[1] != IEEE80211_MESH_CONFIG_LEN)
 200                 return false;
 201
 202         /*
 203          * Ignore mesh capability (last two bytes of the IE) when
 204          * comparing since that may differ between stations taking
 205          * part in the same mesh.
 206          */
 207         return memcmp(ie + 2, meshcfg, IEEE80211_MESH_CONFIG_LEN - 2) == 0;
 208 }
 209
 210 static int cmp_bss(struct cfg80211_bss *a,
 211                    struct cfg80211_bss *b)
 212 {
 213         int r;
 214
 215         if (a->channel != b->channel)
 216                 return b->channel->center_freq - a->channel->center_freq;
 217
 218         r = memcmp(a->bssid, b->bssid, ETH_ALEN);
 219         if (r)
 220                 return r;
 221
 222         if (is_zero_ether_addr(a->bssid)) {
 223                 r = cmp_ies(WLAN_EID_MESH_ID,
 224                             a->information_elements,
 225                             a->len_information_elements,
 226                             b->information_elements,
 227                             b->len_information_elements);
 228                 if (r)
 229                         return r;
 230                 return cmp_ies(WLAN_EID_MESH_CONFIG,
 231                                a->information_elements,
 232                                a->len_information_elements,
 233                                b->information_elements,
 234                                b->len_information_elements);
 235         }
 236
 237         return cmp_ies(WLAN_EID_SSID,
 238                        a->information_elements,
 239                        a->len_information_elements,
 240                        b->information_elements,
 241                        b->len_information_elements);
 242 }
 243
 244 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
 245                                       struct ieee80211_channel *channel,
 246                                       const u8 *bssid,
 247                                       const u8 *ssid, size_t ssid_len,
 248                                       u16 capa_mask, u16 capa_val)
 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 ((bss->pub.capability & capa_mask) != capa_val)
 257                         continue;
 258                 if (channel && bss->pub.channel != channel)
 259                         continue;
 260                 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
 261                         res = bss;
 262                         kref_get(&res->ref);
 263                         break;
 264                 }
 265         }
 266
 267         spin_unlock_bh(&dev->bss_lock);
 268         if (!res)
 269                 return NULL;
 270         return &res->pub;
 271 }
 272 EXPORT_SYMBOL(cfg80211_get_bss);
 273
 274 struct cfg80211_bss *cfg80211_get_mesh(struct wiphy *wiphy,
 275                                        struct ieee80211_channel *channel,
 276                                        const u8 *meshid, size_t meshidlen,
 277                                        const u8 *meshcfg)
 278 {
 279         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 280         struct cfg80211_internal_bss *bss, *res = NULL;
 281
 282         spin_lock_bh(&dev->bss_lock);
 283
 284         list_for_each_entry(bss, &dev->bss_list, list) {
 285                 if (channel && bss->pub.channel != channel)
 286                         continue;
 287                 if (is_mesh(&bss->pub, meshid, meshidlen, meshcfg)) {
 288                         res = bss;
 289                         kref_get(&res->ref);
 290                         break;
 291                 }
 292         }
 293
 294         spin_unlock_bh(&dev->bss_lock);
 295         if (!res)
 296                 return NULL;
 297         return &res->pub;
 298 }
 299 EXPORT_SYMBOL(cfg80211_get_mesh);
 300
 301
 302 static void rb_insert_bss(struct cfg80211_registered_device *dev,
 303                           struct cfg80211_internal_bss *bss)
 304 {
 305         struct rb_node **p = &dev->bss_tree.rb_node;
 306         struct rb_node *parent = NULL;
 307         struct cfg80211_internal_bss *tbss;
 308         int cmp;
 309
 310         while (*p) {
 311                 parent = *p;
 312                 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
 313
 314                 cmp = cmp_bss(&bss->pub, &tbss->pub);
 315
 316                 if (WARN_ON(!cmp)) {
 317                         /* will sort of leak this BSS */
 318                         return;
 319                 }
 320
 321                 if (cmp < 0)
 322                         p = &(*p)->rb_left;
 323                 else
 324                         p = &(*p)->rb_right;
 325         }
 326
 327         rb_link_node(&bss->rbn, parent, p);
 328         rb_insert_color(&bss->rbn, &dev->bss_tree);
 329 }
 330
 331 static struct cfg80211_internal_bss *
 332 rb_find_bss(struct cfg80211_registered_device *dev,
 333             struct cfg80211_internal_bss *res)
 334 {
 335         struct rb_node *n = dev->bss_tree.rb_node;
 336         struct cfg80211_internal_bss *bss;
 337         int r;
 338
 339         while (n) {
 340                 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
 341                 r = cmp_bss(&res->pub, &bss->pub);
 342
 343                 if (r == 0)
 344                         return bss;
 345                 else if (r < 0)
 346                         n = n->rb_left;
 347                 else
 348                         n = n->rb_right;
 349         }
 350
 351         return NULL;
 352 }
 353
 354 static struct cfg80211_internal_bss *
 355 cfg80211_bss_update(struct cfg80211_registered_device *dev,
 356                     struct cfg80211_internal_bss *res,
 357                     bool overwrite)
 358 {
 359         struct cfg80211_internal_bss *found = NULL;
 360         const u8 *meshid, *meshcfg;
 361
 362         /*
 363          * The reference to "res" is donated to this function.
 364          */
 365
 366         if (WARN_ON(!res->pub.channel)) {
 367                 kref_put(&res->ref, bss_release);
 368                 return NULL;
 369         }
 370
 371         res->ts = jiffies;
 372
 373         if (is_zero_ether_addr(res->pub.bssid)) {
 374                 /* must be mesh, verify */
 375                 meshid = find_ie(WLAN_EID_MESH_ID, res->pub.information_elements,
 376                                  res->pub.len_information_elements);
 377                 meshcfg = find_ie(WLAN_EID_MESH_CONFIG,
 378                                   res->pub.information_elements,
 379                                   res->pub.len_information_elements);
 380                 if (!meshid || !meshcfg ||
 381                     meshcfg[1] != IEEE80211_MESH_CONFIG_LEN) {
 382                         /* bogus mesh */
 383                         kref_put(&res->ref, bss_release);
 384                         return NULL;
 385                 }
 386         }
 387
 388         spin_lock_bh(&dev->bss_lock);
 389
 390         found = rb_find_bss(dev, res);
 391
 392         if (found) {
 393                 found->pub.beacon_interval = res->pub.beacon_interval;
 394                 found->pub.tsf = res->pub.tsf;
 395                 found->pub.signal = res->pub.signal;
 396                 found->pub.capability = res->pub.capability;
 397                 found->ts = res->ts;
 398
 399                 /* overwrite IEs */
 400                 if (overwrite) {
 401                         size_t used = dev->wiphy.bss_priv_size + sizeof(*res);
 402                         size_t ielen = res->pub.len_information_elements;
 403
 404                         if (!found->ies_allocated && ksize(found) >= used + ielen) {
 405                                 memcpy(found->pub.information_elements,
 406                                        res->pub.information_elements, ielen);
 407                                 found->pub.len_information_elements = ielen;
 408                         } else {
 409                                 u8 *ies = found->pub.information_elements;
 410
 411                                 if (found->ies_allocated)
 412                                         ies = krealloc(ies, ielen, GFP_ATOMIC);
 413                                 else
 414                                         ies = kmalloc(ielen, GFP_ATOMIC);
 415
 416                                 if (ies) {
 417                                         memcpy(ies, res->pub.information_elements, ielen);
 418                                         found->ies_allocated = true;
 419                                         found->pub.information_elements = ies;
 420                                         found->pub.len_information_elements = ielen;
 421                                 }
 422                         }
 423                 }
 424
 425                 kref_put(&res->ref, bss_release);
 426         } else {
 427                 /* this "consumes" the reference */
 428                 list_add_tail(&res->list, &dev->bss_list);
 429                 rb_insert_bss(dev, res);
 430                 found = res;
 431         }
 432
 433         dev->bss_generation++;
 434         spin_unlock_bh(&dev->bss_lock);
 435
 436         kref_get(&found->ref);
 437         return found;
 438 }
 439
 440 struct cfg80211_bss*
 441 cfg80211_inform_bss(struct wiphy *wiphy,
 442                     struct ieee80211_channel *channel,
 443                     const u8 *bssid,
 444                     u64 timestamp, u16 capability, u16 beacon_interval,
 445                     const u8 *ie, size_t ielen,
 446                     s32 signal, gfp_t gfp)
 447 {
 448         struct cfg80211_internal_bss *res;
 449         size_t privsz;
 450
 451         if (WARN_ON(!wiphy))
 452                 return NULL;
 453
 454         privsz = wiphy->bss_priv_size;
 455
 456         if (WARN_ON(wiphy->signal_type == NL80211_BSS_SIGNAL_UNSPEC &&
 457                         (signal < 0 || signal > 100)))
 458                 return NULL;
 459
 460         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
 461         if (!res)
 462                 return NULL;
 463
 464         memcpy(res->pub.bssid, bssid, ETH_ALEN);
 465         res->pub.channel = channel;
 466         res->pub.signal = signal;
 467         res->pub.tsf = timestamp;
 468         res->pub.beacon_interval = beacon_interval;
 469         res->pub.capability = capability;
 470         /* point to after the private area */
 471         res->pub.information_elements = (u8 *)res + sizeof(*res) + privsz;
 472         memcpy(res->pub.information_elements, ie, ielen);
 473         res->pub.len_information_elements = ielen;
 474
 475         kref_init(&res->ref);
 476
 477         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res, 0);
 478         if (!res)
 479                 return NULL;
 480
 481         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 482                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 483
 484         /* cfg80211_bss_update gives us a referenced result */
 485         return &res->pub;
 486 }
 487 EXPORT_SYMBOL(cfg80211_inform_bss);
 488
 489 struct cfg80211_bss *
 490 cfg80211_inform_bss_frame(struct wiphy *wiphy,
 491                           struct ieee80211_channel *channel,
 492                           struct ieee80211_mgmt *mgmt, size_t len,
 493                           s32 signal, gfp_t gfp)
 494 {
 495         struct cfg80211_internal_bss *res;
 496         size_t ielen = len - offsetof(struct ieee80211_mgmt,
 497                                       u.probe_resp.variable);
 498         bool overwrite;
 499         size_t privsz = wiphy->bss_priv_size;
 500
 501         if (WARN_ON(wiphy->signal_type == NL80211_BSS_SIGNAL_UNSPEC &&
 502                     (signal < 0 || signal > 100)))
 503                 return NULL;
 504
 505         if (WARN_ON(!mgmt || !wiphy ||
 506                     len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
 507                 return NULL;
 508
 509         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
 510         if (!res)
 511                 return NULL;
 512
 513         memcpy(res->pub.bssid, mgmt->bssid, ETH_ALEN);
 514         res->pub.channel = channel;
 515         res->pub.signal = signal;
 516         res->pub.tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
 517         res->pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
 518         res->pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
 519         /* point to after the private area */
 520         res->pub.information_elements = (u8 *)res + sizeof(*res) + privsz;
 521         memcpy(res->pub.information_elements, mgmt->u.probe_resp.variable, ielen);
 522         res->pub.len_information_elements = ielen;
 523
 524         kref_init(&res->ref);
 525
 526         overwrite = ieee80211_is_probe_resp(mgmt->frame_control);
 527
 528         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res, overwrite);
 529         if (!res)
 530                 return NULL;
 531
 532         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 533                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 534
 535         /* cfg80211_bss_update gives us a referenced result */
 536         return &res->pub;
 537 }
 538 EXPORT_SYMBOL(cfg80211_inform_bss_frame);
 539
 540 void cfg80211_put_bss(struct cfg80211_bss *pub)
 541 {
 542         struct cfg80211_internal_bss *bss;
 543
 544         if (!pub)
 545                 return;
 546
 547         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 548         kref_put(&bss->ref, bss_release);
 549 }
 550 EXPORT_SYMBOL(cfg80211_put_bss);
 551
 552 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
 553 {
 554         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 555         struct cfg80211_internal_bss *bss;
 556
 557         if (WARN_ON(!pub))
 558                 return;
 559
 560         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 561
 562         spin_lock_bh(&dev->bss_lock);
 563
 564         list_del(&bss->list);
 565         dev->bss_generation++;
 566         rb_erase(&bss->rbn, &dev->bss_tree);
 567
 568         spin_unlock_bh(&dev->bss_lock);
 569
 570         kref_put(&bss->ref, bss_release);
 571 }
 572 EXPORT_SYMBOL(cfg80211_unlink_bss);
 573
 574 #ifdef CONFIG_WIRELESS_EXT
 575 int cfg80211_wext_siwscan(struct net_device *dev,
 576                           struct iw_request_info *info,
 577                           union iwreq_data *wrqu, char *extra)
 578 {
 579         struct cfg80211_registered_device *rdev;
 580         struct wiphy *wiphy;
 581         struct iw_scan_req *wreq = NULL;
 582         struct cfg80211_scan_request *creq;
 583         int i, err, n_channels = 0;
 584         enum ieee80211_band band;
 585
 586         if (!netif_running(dev))
 587                 return -ENETDOWN;
 588
 589         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
 590
 591         if (IS_ERR(rdev))
 592                 return PTR_ERR(rdev);
 593
 594         if (rdev->scan_req) {
 595                 err = -EBUSY;
 596                 goto out;
 597         }
 598
 599         wiphy = &rdev->wiphy;
 600
 601         for (band = 0; band < IEEE80211_NUM_BANDS; band++)
 602                 if (wiphy->bands[band])
 603                         n_channels += wiphy->bands[band]->n_channels;
 604
 605         creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
 606                        n_channels * sizeof(void *),
 607                        GFP_ATOMIC);
 608         if (!creq) {
 609                 err = -ENOMEM;
 610                 goto out;
 611         }
 612
 613         creq->wiphy = wiphy;
 614         creq->dev = dev;
 615         /* SSIDs come after channels */
 616         creq->ssids = (void *)&creq->channels[n_channels];
 617         creq->n_channels = n_channels;
 618         creq->n_ssids = 1;
 619
 620         /* all channels */
 621         i = 0;
 622         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
 623                 int j;
 624                 if (!wiphy->bands[band])
 625                         continue;
 626                 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
 627                         creq->channels[i] = &wiphy->bands[band]->channels[j];
 628                         i++;
 629                 }
 630         }
 631
 632         /* translate scan request */
 633         if (wrqu->data.length == sizeof(struct iw_scan_req)) {
 634                 wreq = (struct iw_scan_req *)extra;
 635
 636                 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
 637                         if (wreq->essid_len > IEEE80211_MAX_SSID_LEN)
 638                                 return -EINVAL;
 639                         memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
 640                         creq->ssids[0].ssid_len = wreq->essid_len;
 641                 }
 642                 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
 643                         creq->n_ssids = 0;
 644         }
 645
 646         rdev->scan_req = creq;
 647         err = rdev->ops->scan(wiphy, dev, creq);
 648         if (err) {
 649                 rdev->scan_req = NULL;
 650                 kfree(creq);
 651         } else {
 652                 nl80211_send_scan_start(rdev, dev);
 653                 dev_hold(dev);
 654         }
 655  out:
 656         cfg80211_unlock_rdev(rdev);
 657         return err;
 658 }
 659 EXPORT_SYMBOL_GPL(cfg80211_wext_siwscan);
 660
 661 static void ieee80211_scan_add_ies(struct iw_request_info *info,
 662                                    struct cfg80211_bss *bss,
 663                                    char **current_ev, char *end_buf)
 664 {
 665         u8 *pos, *end, *next;
 666         struct iw_event iwe;
 667
 668         if (!bss->information_elements ||
 669             !bss->len_information_elements)
 670                 return;
 671
 672         /*
 673          * If needed, fragment the IEs buffer (at IE boundaries) into short
 674          * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
 675          */
 676         pos = bss->information_elements;
 677         end = pos + bss->len_information_elements;
 678
 679         while (end - pos > IW_GENERIC_IE_MAX) {
 680                 next = pos + 2 + pos[1];
 681                 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
 682                         next = next + 2 + next[1];
 683
 684                 memset(&iwe, 0, sizeof(iwe));
 685                 iwe.cmd = IWEVGENIE;
 686                 iwe.u.data.length = next - pos;
 687                 *current_ev = iwe_stream_add_point(info, *current_ev,
 688                                                    end_buf, &iwe, pos);
 689
 690                 pos = next;
 691         }
 692
 693         if (end > pos) {
 694                 memset(&iwe, 0, sizeof(iwe));
 695                 iwe.cmd = IWEVGENIE;
 696                 iwe.u.data.length = end - pos;
 697                 *current_ev = iwe_stream_add_point(info, *current_ev,
 698                                                    end_buf, &iwe, pos);
 699         }
 700 }
 701
 702 static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
 703 {
 704         unsigned long end = jiffies;
 705
 706         if (end >= start)
 707                 return jiffies_to_msecs(end - start);
 708
 709         return jiffies_to_msecs(end + (MAX_JIFFY_OFFSET - start) + 1);
 710 }
 711
 712 static char *
 713 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
 714               struct cfg80211_internal_bss *bss, char *current_ev,
 715               char *end_buf)
 716 {
 717         struct iw_event iwe;
 718         u8 *buf, *cfg, *p;
 719         u8 *ie = bss->pub.information_elements;
 720         int rem = bss->pub.len_information_elements, i, sig;
 721         bool ismesh = false;
 722
 723         memset(&iwe, 0, sizeof(iwe));
 724         iwe.cmd = SIOCGIWAP;
 725         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
 726         memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
 727         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
 728                                           IW_EV_ADDR_LEN);
 729
 730         memset(&iwe, 0, sizeof(iwe));
 731         iwe.cmd = SIOCGIWFREQ;
 732         iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
 733         iwe.u.freq.e = 0;
 734         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
 735                                           IW_EV_FREQ_LEN);
 736
 737         memset(&iwe, 0, sizeof(iwe));
 738         iwe.cmd = SIOCGIWFREQ;
 739         iwe.u.freq.m = bss->pub.channel->center_freq;
 740         iwe.u.freq.e = 6;
 741         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
 742                                           IW_EV_FREQ_LEN);
 743
 744         if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
 745                 memset(&iwe, 0, sizeof(iwe));
 746                 iwe.cmd = IWEVQUAL;
 747                 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
 748                                      IW_QUAL_NOISE_INVALID |
 749                                      IW_QUAL_QUAL_UPDATED;
 750                 switch (wiphy->signal_type) {
 751                 case CFG80211_SIGNAL_TYPE_MBM:
 752                         sig = bss->pub.signal / 100;
 753                         iwe.u.qual.level = sig;
 754                         iwe.u.qual.updated |= IW_QUAL_DBM;
 755                         if (sig < -110)         /* rather bad */
 756                                 sig = -110;
 757                         else if (sig > -40)     /* perfect */
 758                                 sig = -40;
 759                         /* will give a range of 0 .. 70 */
 760                         iwe.u.qual.qual = sig + 110;
 761                         break;
 762                 case CFG80211_SIGNAL_TYPE_UNSPEC:
 763                         iwe.u.qual.level = bss->pub.signal;
 764                         /* will give range 0 .. 100 */
 765                         iwe.u.qual.qual = bss->pub.signal;
 766                         break;
 767                 default:
 768                         /* not reached */
 769                         break;
 770                 }
 771                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
 772                                                   &iwe, IW_EV_QUAL_LEN);
 773         }
 774
 775         memset(&iwe, 0, sizeof(iwe));
 776         iwe.cmd = SIOCGIWENCODE;
 777         if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
 778                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
 779         else
 780                 iwe.u.data.flags = IW_ENCODE_DISABLED;
 781         iwe.u.data.length = 0;
 782         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
 783                                           &iwe, "");
 784
 785         while (rem >= 2) {
 786                 /* invalid data */
 787                 if (ie[1] > rem - 2)
 788                         break;
 789
 790                 switch (ie[0]) {
 791                 case WLAN_EID_SSID:
 792                         memset(&iwe, 0, sizeof(iwe));
 793                         iwe.cmd = SIOCGIWESSID;
 794                         iwe.u.data.length = ie[1];
 795                         iwe.u.data.flags = 1;
 796                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
 797                                                           &iwe, ie + 2);
 798                         break;
 799                 case WLAN_EID_MESH_ID:
 800                         memset(&iwe, 0, sizeof(iwe));
 801                         iwe.cmd = SIOCGIWESSID;
 802                         iwe.u.data.length = ie[1];
 803                         iwe.u.data.flags = 1;
 804                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
 805                                                           &iwe, ie + 2);
 806                         break;
 807                 case WLAN_EID_MESH_CONFIG:
 808                         ismesh = true;
 809                         if (ie[1] != IEEE80211_MESH_CONFIG_LEN)
 810                                 break;
 811                         buf = kmalloc(50, GFP_ATOMIC);
 812                         if (!buf)
 813                                 break;
 814                         cfg = ie + 2;
 815                         memset(&iwe, 0, sizeof(iwe));
 816                         iwe.cmd = IWEVCUSTOM;
 817                         sprintf(buf, "Mesh network (version %d)", cfg[0]);
 818                         iwe.u.data.length = strlen(buf);
 819                         current_ev = iwe_stream_add_point(info, current_ev,
 820                                                           end_buf,
 821                                                           &iwe, buf);
 822                         sprintf(buf, "Path Selection Protocol ID: "
 823                                 "0x%02X%02X%02X%02X", cfg[1], cfg[2], cfg[3],
 824                                                         cfg[4]);
 825                         iwe.u.data.length = strlen(buf);
 826                         current_ev = iwe_stream_add_point(info, current_ev,
 827                                                           end_buf,
 828                                                           &iwe, buf);
 829                         sprintf(buf, "Path Selection Metric ID: "
 830                                 "0x%02X%02X%02X%02X", cfg[5], cfg[6], cfg[7],
 831                                                         cfg[8]);
 832                         iwe.u.data.length = strlen(buf);
 833                         current_ev = iwe_stream_add_point(info, current_ev,
 834                                                           end_buf,
 835                                                           &iwe, buf);
 836                         sprintf(buf, "Congestion Control Mode ID: "
 837                                 "0x%02X%02X%02X%02X", cfg[9], cfg[10],
 838                                                         cfg[11], cfg[12]);
 839                         iwe.u.data.length = strlen(buf);
 840                         current_ev = iwe_stream_add_point(info, current_ev,
 841                                                           end_buf,
 842                                                           &iwe, buf);
 843                         sprintf(buf, "Channel Precedence: "
 844                                 "0x%02X%02X%02X%02X", cfg[13], cfg[14],
 845                                                         cfg[15], cfg[16]);
 846                         iwe.u.data.length = strlen(buf);
 847                         current_ev = iwe_stream_add_point(info, current_ev,
 848                                                           end_buf,
 849                                                           &iwe, buf);
 850                         kfree(buf);
 851                         break;
 852                 case WLAN_EID_SUPP_RATES:
 853                 case WLAN_EID_EXT_SUPP_RATES:
 854                         /* display all supported rates in readable format */
 855                         p = current_ev + iwe_stream_lcp_len(info);
 856
 857                         memset(&iwe, 0, sizeof(iwe));
 858                         iwe.cmd = SIOCGIWRATE;
 859                         /* Those two flags are ignored... */
 860                         iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
 861
 862                         for (i = 0; i < ie[1]; i++) {
 863                                 iwe.u.bitrate.value =
 864                                         ((ie[i + 2] & 0x7f) * 500000);
 865                                 p = iwe_stream_add_value(info, current_ev, p,
 866                                                 end_buf, &iwe, IW_EV_PARAM_LEN);
 867                         }
 868                         current_ev = p;
 869                         break;
 870                 }
 871                 rem -= ie[1] + 2;
 872                 ie += ie[1] + 2;
 873         }
 874
 875         if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS)
 876             || ismesh) {
 877                 memset(&iwe, 0, sizeof(iwe));
 878                 iwe.cmd = SIOCGIWMODE;
 879                 if (ismesh)
 880                         iwe.u.mode = IW_MODE_MESH;
 881                 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
 882                         iwe.u.mode = IW_MODE_MASTER;
 883                 else
 884                         iwe.u.mode = IW_MODE_ADHOC;
 885                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
 886                                                   &iwe, IW_EV_UINT_LEN);
 887         }
 888
 889         buf = kmalloc(30, GFP_ATOMIC);
 890         if (buf) {
 891                 memset(&iwe, 0, sizeof(iwe));
 892                 iwe.cmd = IWEVCUSTOM;
 893                 sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->pub.tsf));
 894                 iwe.u.data.length = strlen(buf);
 895                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
 896                                                   &iwe, buf);
 897                 memset(&iwe, 0, sizeof(iwe));
 898                 iwe.cmd = IWEVCUSTOM;
 899                 sprintf(buf, " Last beacon: %ums ago",
 900                         elapsed_jiffies_msecs(bss->ts));
 901                 iwe.u.data.length = strlen(buf);
 902                 current_ev = iwe_stream_add_point(info, current_ev,
 903                                                   end_buf, &iwe, buf);
 904                 kfree(buf);
 905         }
 906
 907         ieee80211_scan_add_ies(info, &bss->pub, &current_ev, end_buf);
 908
 909         return current_ev;
 910 }
 911
 912
 913 static int ieee80211_scan_results(struct cfg80211_registered_device *dev,
 914                                   struct iw_request_info *info,
 915                                   char *buf, size_t len)
 916 {
 917         char *current_ev = buf;
 918         char *end_buf = buf + len;
 919         struct cfg80211_internal_bss *bss;
 920
 921         spin_lock_bh(&dev->bss_lock);
 922         cfg80211_bss_expire(dev);
 923
 924         list_for_each_entry(bss, &dev->bss_list, list) {
 925                 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
 926                         spin_unlock_bh(&dev->bss_lock);
 927                         return -E2BIG;
 928                 }
 929                 current_ev = ieee80211_bss(&dev->wiphy, info, bss,
 930                                            current_ev, end_buf);
 931         }
 932         spin_unlock_bh(&dev->bss_lock);
 933         return current_ev - buf;
 934 }
 935
 936
 937 int cfg80211_wext_giwscan(struct net_device *dev,
 938                           struct iw_request_info *info,
 939                           struct iw_point *data, char *extra)
 940 {
 941         struct cfg80211_registered_device *rdev;
 942         int res;
 943
 944         if (!netif_running(dev))
 945                 return -ENETDOWN;
 946
 947         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
 948
 949         if (IS_ERR(rdev))
 950                 return PTR_ERR(rdev);
 951
 952         if (rdev->scan_req) {
 953                 res = -EAGAIN;
 954                 goto out;
 955         }
 956
 957         res = ieee80211_scan_results(rdev, info, extra, data->length);
 958         data->length = 0;
 959         if (res >= 0) {
 960                 data->length = res;
 961                 res = 0;
 962         }
 963
 964  out:
 965         cfg80211_unlock_rdev(rdev);
 966         return res;
 967 }
 968 EXPORT_SYMBOL_GPL(cfg80211_wext_giwscan);
 969 #endif