net/wireless/scan.c

   1 /*
   2  * cfg80211 scan result handling
   3  *
   4  * Copyright 2008 Johannes Berg <johannes@sipsolutions.net>
   5  */
   6 #include <linux/kernel.h>
   7 #include <linux/slab.h>
   8 #include <linux/module.h>
   9 #include <linux/netdevice.h>
  10 #include <linux/wireless.h>
  11 #include <linux/nl80211.h>
  12 #include <linux/etherdevice.h>
  13 #include <net/arp.h>
  14 #include <net/cfg80211.h>
  15 #include <net/cfg80211-wext.h>
  16 #include <net/iw_handler.h>
  17 #include "core.h"
  18 #include "nl80211.h"
  19 #include "wext-compat.h"
  20
  21 #define IEEE80211_SCAN_RESULT_EXPIRE    (15 * HZ)
  22
  23 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev, bool leak)
  24 {
  25         struct cfg80211_scan_request *request;
  26         struct net_device *dev;
  27 #ifdef CONFIG_CFG80211_WEXT
  28         union iwreq_data wrqu;
  29 #endif
  30
  31         ASSERT_RDEV_LOCK(rdev);
  32
  33         request = rdev->scan_req;
  34
  35         if (!request)
  36                 return;
  37
  38         dev = request->dev;
  39
  40         /*
  41          * This must be before sending the other events!
  42          * Otherwise, wpa_supplicant gets completely confused with
  43          * wext events.
  44          */
  45         cfg80211_sme_scan_done(dev);
  46
  47         if (request->aborted)
  48                 nl80211_send_scan_aborted(rdev, dev);
  49         else
  50                 nl80211_send_scan_done(rdev, dev);
  51
  52 #ifdef CONFIG_CFG80211_WEXT
  53         if (!request->aborted) {
  54                 memset(&wrqu, 0, sizeof(wrqu));
  55
  56                 wireless_send_event(dev, SIOCGIWSCAN, &wrqu, NULL);
  57         }
  58 #endif
  59
  60         dev_put(dev);
  61
  62         rdev->scan_req = NULL;
  63
  64         /*
  65          * OK. If this is invoked with "leak" then we can't
  66          * free this ... but we've cleaned it up anyway. The
  67          * driver failed to call the scan_done callback, so
  68          * all bets are off, it might still be trying to use
  69          * the scan request or not ... if it accesses the dev
  70          * in there (it shouldn't anyway) then it may crash.
  71          */
  72         if (!leak)
  73                 kfree(request);
  74 }
  75
  76 void __cfg80211_scan_done(struct work_struct *wk)
  77 {
  78         struct cfg80211_registered_device *rdev;
  79
  80         rdev = container_of(wk, struct cfg80211_registered_device,
  81                             scan_done_wk);
  82
  83         cfg80211_lock_rdev(rdev);
  84         ___cfg80211_scan_done(rdev, false);
  85         cfg80211_unlock_rdev(rdev);
  86 }
  87
  88 void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
  89 {
  90         WARN_ON(request != wiphy_to_dev(request->wiphy)->scan_req);
  91
  92         request->aborted = aborted;
  93         queue_work(cfg80211_wq, &wiphy_to_dev(request->wiphy)->scan_done_wk);
  94 }
  95 EXPORT_SYMBOL(cfg80211_scan_done);
  96
  97 void __cfg80211_sched_scan_results(struct work_struct *wk)
  98 {
  99         struct cfg80211_registered_device *rdev;
 100
 101         rdev = container_of(wk, struct cfg80211_registered_device,
 102                             sched_scan_results_wk);
 103
 104         mutex_lock(&rdev->sched_scan_mtx);
 105
 106         /* we don't have sched_scan_req anymore if the scan is stopping */
 107         if (rdev->sched_scan_req)
 108                 nl80211_send_sched_scan_results(rdev,
 109                                                 rdev->sched_scan_req->dev);
 110
 111         mutex_unlock(&rdev->sched_scan_mtx);
 112 }
 113
 114 void cfg80211_sched_scan_results(struct wiphy *wiphy)
 115 {
 116         /* ignore if we're not scanning */
 117         if (wiphy_to_dev(wiphy)->sched_scan_req)
 118                 queue_work(cfg80211_wq,
 119                            &wiphy_to_dev(wiphy)->sched_scan_results_wk);
 120 }
 121 EXPORT_SYMBOL(cfg80211_sched_scan_results);
 122
 123 void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
 124 {
 125         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
 126
 127         mutex_lock(&rdev->sched_scan_mtx);
 128         __cfg80211_stop_sched_scan(rdev, true);
 129         mutex_unlock(&rdev->sched_scan_mtx);
 130 }
 131 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
 132
 133 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
 134                                bool driver_initiated)
 135 {
 136         struct net_device *dev;
 137
 138         lockdep_assert_held(&rdev->sched_scan_mtx);
 139
 140         if (!rdev->sched_scan_req)
 141                 return -ENOENT;
 142
 143         dev = rdev->sched_scan_req->dev;
 144
 145         if (!driver_initiated) {
 146                 int err = rdev->ops->sched_scan_stop(&rdev->wiphy, dev);
 147                 if (err)
 148                         return err;
 149         }
 150
 151         nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED);
 152
 153         kfree(rdev->sched_scan_req);
 154         rdev->sched_scan_req = NULL;
 155
 156         return 0;
 157 }
 158
 159 static void bss_release(struct kref *ref)
 160 {
 161         struct cfg80211_internal_bss *bss;
 162
 163         bss = container_of(ref, struct cfg80211_internal_bss, ref);
 164         if (bss->pub.free_priv)
 165                 bss->pub.free_priv(&bss->pub);
 166
 167         if (bss->beacon_ies_allocated)
 168                 kfree(bss->pub.beacon_ies);
 169         if (bss->proberesp_ies_allocated)
 170                 kfree(bss->pub.proberesp_ies);
 171
 172         BUG_ON(atomic_read(&bss->hold));
 173
 174         kfree(bss);
 175 }
 176
 177 /* must hold dev->bss_lock! */
 178 void cfg80211_bss_age(struct cfg80211_registered_device *dev,
 179                       unsigned long age_secs)
 180 {
 181         struct cfg80211_internal_bss *bss;
 182         unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
 183
 184         list_for_each_entry(bss, &dev->bss_list, list) {
 185                 bss->ts -= age_jiffies;
 186         }
 187 }
 188
 189 /* must hold dev->bss_lock! */
 190 static void __cfg80211_unlink_bss(struct cfg80211_registered_device *dev,
 191                                   struct cfg80211_internal_bss *bss)
 192 {
 193         list_del_init(&bss->list);
 194         rb_erase(&bss->rbn, &dev->bss_tree);
 195         kref_put(&bss->ref, bss_release);
 196 }
 197
 198 /* must hold dev->bss_lock! */
 199 void cfg80211_bss_expire(struct cfg80211_registered_device *dev)
 200 {
 201         struct cfg80211_internal_bss *bss, *tmp;
 202         bool expired = false;
 203
 204         list_for_each_entry_safe(bss, tmp, &dev->bss_list, list) {
 205                 if (atomic_read(&bss->hold))
 206                         continue;
 207                 if (!time_after(jiffies, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE))
 208                         continue;
 209                 __cfg80211_unlink_bss(dev, bss);
 210                 expired = true;
 211         }
 212
 213         if (expired)
 214                 dev->bss_generation++;
 215 }
 216
 217 const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len)
 218 {
 219         while (len > 2 && ies[0] != eid) {
 220                 len -= ies[1] + 2;
 221                 ies += ies[1] + 2;
 222         }
 223         if (len < 2)
 224                 return NULL;
 225         if (len < 2 + ies[1])
 226                 return NULL;
 227         return ies;
 228 }
 229 EXPORT_SYMBOL(cfg80211_find_ie);
 230
 231 const u8 *cfg80211_find_vendor_ie(unsigned int oui, u8 oui_type,
 232                                   const u8 *ies, int len)
 233 {
 234         struct ieee80211_vendor_ie *ie;
 235         const u8 *pos = ies, *end = ies + len;
 236         int ie_oui;
 237
 238         while (pos < end) {
 239                 pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos,
 240                                        end - pos);
 241                 if (!pos)
 242                         return NULL;
 243
 244                 if (end - pos < sizeof(*ie))
 245                         return NULL;
 246
 247                 ie = (struct ieee80211_vendor_ie *)pos;
 248                 ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2];
 249                 if (ie_oui == oui && ie->oui_type == oui_type)
 250                         return pos;
 251
 252                 pos += 2 + ie->len;
 253         }
 254         return NULL;
 255 }
 256 EXPORT_SYMBOL(cfg80211_find_vendor_ie);
 257
 258 static int cmp_ies(u8 num, u8 *ies1, size_t len1, u8 *ies2, size_t len2)
 259 {
 260         const u8 *ie1 = cfg80211_find_ie(num, ies1, len1);
 261         const u8 *ie2 = cfg80211_find_ie(num, ies2, len2);
 262
 263         /* equal if both missing */
 264         if (!ie1 && !ie2)
 265                 return 0;
 266         /* sort missing IE before (left of) present IE */
 267         if (!ie1)
 268                 return -1;
 269         if (!ie2)
 270                 return 1;
 271
 272         /* sort by length first, then by contents */
 273         if (ie1[1] != ie2[1])
 274                 return ie2[1] - ie1[1];
 275         return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
 276 }
 277
 278 static bool is_bss(struct cfg80211_bss *a,
 279                    const u8 *bssid,
 280                    const u8 *ssid, size_t ssid_len)
 281 {
 282         const u8 *ssidie;
 283
 284         if (bssid && compare_ether_addr(a->bssid, bssid))
 285                 return false;
 286
 287         if (!ssid)
 288                 return true;
 289
 290         ssidie = cfg80211_find_ie(WLAN_EID_SSID,
 291                                   a->information_elements,
 292                                   a->len_information_elements);
 293         if (!ssidie)
 294                 return false;
 295         if (ssidie[1] != ssid_len)
 296                 return false;
 297         return memcmp(ssidie + 2, ssid, ssid_len) == 0;
 298 }
 299
 300 static bool is_mesh_bss(struct cfg80211_bss *a)
 301 {
 302         const u8 *ie;
 303
 304         if (!WLAN_CAPABILITY_IS_STA_BSS(a->capability))
 305                 return false;
 306
 307         ie = cfg80211_find_ie(WLAN_EID_MESH_ID,
 308                               a->information_elements,
 309                               a->len_information_elements);
 310         if (!ie)
 311                 return false;
 312
 313         ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
 314                               a->information_elements,
 315                               a->len_information_elements);
 316         if (!ie)
 317                 return false;
 318
 319         return true;
 320 }
 321
 322 static bool is_mesh(struct cfg80211_bss *a,
 323                     const u8 *meshid, size_t meshidlen,
 324                     const u8 *meshcfg)
 325 {
 326         const u8 *ie;
 327
 328         if (!WLAN_CAPABILITY_IS_STA_BSS(a->capability))
 329                 return false;
 330
 331         ie = cfg80211_find_ie(WLAN_EID_MESH_ID,
 332                               a->information_elements,
 333                               a->len_information_elements);
 334         if (!ie)
 335                 return false;
 336         if (ie[1] != meshidlen)
 337                 return false;
 338         if (memcmp(ie + 2, meshid, meshidlen))
 339                 return false;
 340
 341         ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
 342                               a->information_elements,
 343                               a->len_information_elements);
 344         if (!ie)
 345                 return false;
 346         if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
 347                 return false;
 348
 349         /*
 350          * Ignore mesh capability (last two bytes of the IE) when
 351          * comparing since that may differ between stations taking
 352          * part in the same mesh.
 353          */
 354         return memcmp(ie + 2, meshcfg,
 355             sizeof(struct ieee80211_meshconf_ie) - 2) == 0;
 356 }
 357
 358 static int cmp_bss(struct cfg80211_bss *a,
 359                    struct cfg80211_bss *b)
 360 {
 361         int r;
 362
 363         if (a->channel != b->channel)
 364                 return b->channel->center_freq - a->channel->center_freq;
 365
 366         if (is_mesh_bss(a) && is_mesh_bss(b)) {
 367                 r = cmp_ies(WLAN_EID_MESH_ID,
 368                             a->information_elements,
 369                             a->len_information_elements,
 370                             b->information_elements,
 371                             b->len_information_elements);
 372                 if (r)
 373                         return r;
 374                 return cmp_ies(WLAN_EID_MESH_CONFIG,
 375                                a->information_elements,
 376                                a->len_information_elements,
 377                                b->information_elements,
 378                                b->len_information_elements);
 379         }
 380
 381         r = memcmp(a->bssid, b->bssid, ETH_ALEN);
 382         if (r)
 383                 return r;
 384
 385         return cmp_ies(WLAN_EID_SSID,
 386                        a->information_elements,
 387                        a->len_information_elements,
 388                        b->information_elements,
 389                        b->len_information_elements);
 390 }
 391
 392 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
 393                                       struct ieee80211_channel *channel,
 394                                       const u8 *bssid,
 395                                       const u8 *ssid, size_t ssid_len,
 396                                       u16 capa_mask, u16 capa_val)
 397 {
 398         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 399         struct cfg80211_internal_bss *bss, *res = NULL;
 400         unsigned long now = jiffies;
 401
 402         spin_lock_bh(&dev->bss_lock);
 403
 404         list_for_each_entry(bss, &dev->bss_list, list) {
 405                 if ((bss->pub.capability & capa_mask) != capa_val)
 406                         continue;
 407                 if (channel && bss->pub.channel != channel)
 408                         continue;
 409                 /* Don't get expired BSS structs */
 410                 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
 411                     !atomic_read(&bss->hold))
 412                         continue;
 413                 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
 414                         res = bss;
 415                         kref_get(&res->ref);
 416                         break;
 417                 }
 418         }
 419
 420         spin_unlock_bh(&dev->bss_lock);
 421         if (!res)
 422                 return NULL;
 423         return &res->pub;
 424 }
 425 EXPORT_SYMBOL(cfg80211_get_bss);
 426
 427 struct cfg80211_bss *cfg80211_get_mesh(struct wiphy *wiphy,
 428                                        struct ieee80211_channel *channel,
 429                                        const u8 *meshid, size_t meshidlen,
 430                                        const u8 *meshcfg)
 431 {
 432         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 433         struct cfg80211_internal_bss *bss, *res = NULL;
 434
 435         spin_lock_bh(&dev->bss_lock);
 436
 437         list_for_each_entry(bss, &dev->bss_list, list) {
 438                 if (channel && bss->pub.channel != channel)
 439                         continue;
 440                 if (is_mesh(&bss->pub, meshid, meshidlen, meshcfg)) {
 441                         res = bss;
 442                         kref_get(&res->ref);
 443                         break;
 444                 }
 445         }
 446
 447         spin_unlock_bh(&dev->bss_lock);
 448         if (!res)
 449                 return NULL;
 450         return &res->pub;
 451 }
 452 EXPORT_SYMBOL(cfg80211_get_mesh);
 453
 454
 455 static void rb_insert_bss(struct cfg80211_registered_device *dev,
 456                           struct cfg80211_internal_bss *bss)
 457 {
 458         struct rb_node **p = &dev->bss_tree.rb_node;
 459         struct rb_node *parent = NULL;
 460         struct cfg80211_internal_bss *tbss;
 461         int cmp;
 462
 463         while (*p) {
 464                 parent = *p;
 465                 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
 466
 467                 cmp = cmp_bss(&bss->pub, &tbss->pub);
 468
 469                 if (WARN_ON(!cmp)) {
 470                         /* will sort of leak this BSS */
 471                         return;
 472                 }
 473
 474                 if (cmp < 0)
 475                         p = &(*p)->rb_left;
 476                 else
 477                         p = &(*p)->rb_right;
 478         }
 479
 480         rb_link_node(&bss->rbn, parent, p);
 481         rb_insert_color(&bss->rbn, &dev->bss_tree);
 482 }
 483
 484 static struct cfg80211_internal_bss *
 485 rb_find_bss(struct cfg80211_registered_device *dev,
 486             struct cfg80211_internal_bss *res)
 487 {
 488         struct rb_node *n = dev->bss_tree.rb_node;
 489         struct cfg80211_internal_bss *bss;
 490         int r;
 491
 492         while (n) {
 493                 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
 494                 r = cmp_bss(&res->pub, &bss->pub);
 495
 496                 if (r == 0)
 497                         return bss;
 498                 else if (r < 0)
 499                         n = n->rb_left;
 500                 else
 501                         n = n->rb_right;
 502         }
 503
 504         return NULL;
 505 }
 506
 507 static struct cfg80211_internal_bss *
 508 cfg80211_bss_update(struct cfg80211_registered_device *dev,
 509                     struct cfg80211_internal_bss *res)
 510 {
 511         struct cfg80211_internal_bss *found = NULL;
 512
 513         /*
 514          * The reference to "res" is donated to this function.
 515          */
 516
 517         if (WARN_ON(!res->pub.channel)) {
 518                 kref_put(&res->ref, bss_release);
 519                 return NULL;
 520         }
 521
 522         res->ts = jiffies;
 523
 524         spin_lock_bh(&dev->bss_lock);
 525
 526         found = rb_find_bss(dev, res);
 527
 528         if (found) {
 529                 found->pub.beacon_interval = res->pub.beacon_interval;
 530                 found->pub.tsf = res->pub.tsf;
 531                 found->pub.signal = res->pub.signal;
 532                 found->pub.capability = res->pub.capability;
 533                 found->ts = res->ts;
 534
 535                 /* Update IEs */
 536                 if (res->pub.proberesp_ies) {
 537                         size_t used = dev->wiphy.bss_priv_size + sizeof(*res);
 538                         size_t ielen = res->pub.len_proberesp_ies;
 539
 540                         if (found->pub.proberesp_ies &&
 541                             !found->proberesp_ies_allocated &&
 542                             ksize(found) >= used + ielen) {
 543                                 memcpy(found->pub.proberesp_ies,
 544                                        res->pub.proberesp_ies, ielen);
 545                                 found->pub.len_proberesp_ies = ielen;
 546                         } else {
 547                                 u8 *ies = found->pub.proberesp_ies;
 548
 549                                 if (found->proberesp_ies_allocated)
 550                                         ies = krealloc(ies, ielen, GFP_ATOMIC);
 551                                 else
 552                                         ies = kmalloc(ielen, GFP_ATOMIC);
 553
 554                                 if (ies) {
 555                                         memcpy(ies, res->pub.proberesp_ies,
 556                                                ielen);
 557                                         found->proberesp_ies_allocated = true;
 558                                         found->pub.proberesp_ies = ies;
 559                                         found->pub.len_proberesp_ies = ielen;
 560                                 }
 561                         }
 562
 563                         /* Override possible earlier Beacon frame IEs */
 564                         found->pub.information_elements =
 565                                 found->pub.proberesp_ies;
 566                         found->pub.len_information_elements =
 567                                 found->pub.len_proberesp_ies;
 568                 }
 569                 if (res->pub.beacon_ies) {
 570                         size_t used = dev->wiphy.bss_priv_size + sizeof(*res);
 571                         size_t ielen = res->pub.len_beacon_ies;
 572                         bool information_elements_is_beacon_ies =
 573                                 (found->pub.information_elements ==
 574                                  found->pub.beacon_ies);
 575
 576                         if (found->pub.beacon_ies &&
 577                             !found->beacon_ies_allocated &&
 578                             ksize(found) >= used + ielen) {
 579                                 memcpy(found->pub.beacon_ies,
 580                                        res->pub.beacon_ies, ielen);
 581                                 found->pub.len_beacon_ies = ielen;
 582                         } else {
 583                                 u8 *ies = found->pub.beacon_ies;
 584
 585                                 if (found->beacon_ies_allocated)
 586                                         ies = krealloc(ies, ielen, GFP_ATOMIC);
 587                                 else
 588                                         ies = kmalloc(ielen, GFP_ATOMIC);
 589
 590                                 if (ies) {
 591                                         memcpy(ies, res->pub.beacon_ies,
 592                                                ielen);
 593                                         found->beacon_ies_allocated = true;
 594                                         found->pub.beacon_ies = ies;
 595                                         found->pub.len_beacon_ies = ielen;
 596                                 }
 597                         }
 598
 599                         /* Override IEs if they were from a beacon before */
 600                         if (information_elements_is_beacon_ies) {
 601                                 found->pub.information_elements =
 602                                         found->pub.beacon_ies;
 603                                 found->pub.len_information_elements =
 604                                         found->pub.len_beacon_ies;
 605                         }
 606                 }
 607
 608                 kref_put(&res->ref, bss_release);
 609         } else {
 610                 /* this "consumes" the reference */
 611                 list_add_tail(&res->list, &dev->bss_list);
 612                 rb_insert_bss(dev, res);
 613                 found = res;
 614         }
 615
 616         dev->bss_generation++;
 617         spin_unlock_bh(&dev->bss_lock);
 618
 619         kref_get(&found->ref);
 620         return found;
 621 }
 622
 623 struct cfg80211_bss*
 624 cfg80211_inform_bss(struct wiphy *wiphy,
 625                     struct ieee80211_channel *channel,
 626                     const u8 *bssid,
 627                     u64 timestamp, u16 capability, u16 beacon_interval,
 628                     const u8 *ie, size_t ielen,
 629                     s32 signal, gfp_t gfp)
 630 {
 631         struct cfg80211_internal_bss *res;
 632         size_t privsz;
 633
 634         if (WARN_ON(!wiphy))
 635                 return NULL;
 636
 637         privsz = wiphy->bss_priv_size;
 638
 639         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
 640                         (signal < 0 || signal > 100)))
 641                 return NULL;
 642
 643         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
 644         if (!res)
 645                 return NULL;
 646
 647         memcpy(res->pub.bssid, bssid, ETH_ALEN);
 648         res->pub.channel = channel;
 649         res->pub.signal = signal;
 650         res->pub.tsf = timestamp;
 651         res->pub.beacon_interval = beacon_interval;
 652         res->pub.capability = capability;
 653         /*
 654          * Since we do not know here whether the IEs are from a Beacon or Probe
 655          * Response frame, we need to pick one of the options and only use it
 656          * with the driver that does not provide the full Beacon/Probe Response
 657          * frame. Use Beacon frame pointer to avoid indicating that this should
 658          * override the information_elements pointer should we have received an
 659          * earlier indication of Probe Response data.
 660          *
 661          * The initial buffer for the IEs is allocated with the BSS entry and
 662          * is located after the private area.
 663          */
 664         res->pub.beacon_ies = (u8 *)res + sizeof(*res) + privsz;
 665         memcpy(res->pub.beacon_ies, ie, ielen);
 666         res->pub.len_beacon_ies = ielen;
 667         res->pub.information_elements = res->pub.beacon_ies;
 668         res->pub.len_information_elements = res->pub.len_beacon_ies;
 669
 670         kref_init(&res->ref);
 671
 672         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res);
 673         if (!res)
 674                 return NULL;
 675
 676         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 677                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 678
 679         /* cfg80211_bss_update gives us a referenced result */
 680         return &res->pub;
 681 }
 682 EXPORT_SYMBOL(cfg80211_inform_bss);
 683
 684 struct cfg80211_bss *
 685 cfg80211_inform_bss_frame(struct wiphy *wiphy,
 686                           struct ieee80211_channel *channel,
 687                           struct ieee80211_mgmt *mgmt, size_t len,
 688                           s32 signal, gfp_t gfp)
 689 {
 690         struct cfg80211_internal_bss *res;
 691         size_t ielen = len - offsetof(struct ieee80211_mgmt,
 692                                       u.probe_resp.variable);
 693         size_t privsz;
 694
 695         if (WARN_ON(!mgmt))
 696                 return NULL;
 697
 698         if (WARN_ON(!wiphy))
 699                 return NULL;
 700
 701         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
 702                     (signal < 0 || signal > 100)))
 703                 return NULL;
 704
 705         if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
 706                 return NULL;
 707
 708         privsz = wiphy->bss_priv_size;
 709
 710         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
 711         if (!res)
 712                 return NULL;
 713
 714         memcpy(res->pub.bssid, mgmt->bssid, ETH_ALEN);
 715         res->pub.channel = channel;
 716         res->pub.signal = signal;
 717         res->pub.tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
 718         res->pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
 719         res->pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
 720         /*
 721          * The initial buffer for the IEs is allocated with the BSS entry and
 722          * is located after the private area.
 723          */
 724         if (ieee80211_is_probe_resp(mgmt->frame_control)) {
 725                 res->pub.proberesp_ies = (u8 *) res + sizeof(*res) + privsz;
 726                 memcpy(res->pub.proberesp_ies, mgmt->u.probe_resp.variable,
 727                        ielen);
 728                 res->pub.len_proberesp_ies = ielen;
 729                 res->pub.information_elements = res->pub.proberesp_ies;
 730                 res->pub.len_information_elements = res->pub.len_proberesp_ies;
 731         } else {
 732                 res->pub.beacon_ies = (u8 *) res + sizeof(*res) + privsz;
 733                 memcpy(res->pub.beacon_ies, mgmt->u.beacon.variable, ielen);
 734                 res->pub.len_beacon_ies = ielen;
 735                 res->pub.information_elements = res->pub.beacon_ies;
 736                 res->pub.len_information_elements = res->pub.len_beacon_ies;
 737         }
 738
 739         kref_init(&res->ref);
 740
 741         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res);
 742         if (!res)
 743                 return NULL;
 744
 745         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 746                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 747
 748         /* cfg80211_bss_update gives us a referenced result */
 749         return &res->pub;
 750 }
 751 EXPORT_SYMBOL(cfg80211_inform_bss_frame);
 752
 753 void cfg80211_put_bss(struct cfg80211_bss *pub)
 754 {
 755         struct cfg80211_internal_bss *bss;
 756
 757         if (!pub)
 758                 return;
 759
 760         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 761         kref_put(&bss->ref, bss_release);
 762 }
 763 EXPORT_SYMBOL(cfg80211_put_bss);
 764
 765 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
 766 {
 767         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 768         struct cfg80211_internal_bss *bss;
 769
 770         if (WARN_ON(!pub))
 771                 return;
 772
 773         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 774
 775         spin_lock_bh(&dev->bss_lock);
 776         if (!list_empty(&bss->list)) {
 777                 __cfg80211_unlink_bss(dev, bss);
 778                 dev->bss_generation++;
 779         }
 780         spin_unlock_bh(&dev->bss_lock);
 781 }
 782 EXPORT_SYMBOL(cfg80211_unlink_bss);
 783
 784 #ifdef CONFIG_CFG80211_WEXT
 785 int cfg80211_wext_siwscan(struct net_device *dev,
 786                           struct iw_request_info *info,
 787                           union iwreq_data *wrqu, char *extra)
 788 {
 789         struct cfg80211_registered_device *rdev;
 790         struct wiphy *wiphy;
 791         struct iw_scan_req *wreq = NULL;
 792         struct cfg80211_scan_request *creq = NULL;
 793         int i, err, n_channels = 0;
 794         enum ieee80211_band band;
 795
 796         if (!netif_running(dev))
 797                 return -ENETDOWN;
 798
 799         if (wrqu->data.length == sizeof(struct iw_scan_req))
 800                 wreq = (struct iw_scan_req *)extra;
 801
 802         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
 803
 804         if (IS_ERR(rdev))
 805                 return PTR_ERR(rdev);
 806
 807         if (rdev->scan_req) {
 808                 err = -EBUSY;
 809                 goto out;
 810         }
 811
 812         wiphy = &rdev->wiphy;
 813
 814         /* Determine number of channels, needed to allocate creq */
 815         if (wreq && wreq->num_channels)
 816                 n_channels = wreq->num_channels;
 817         else {
 818                 for (band = 0; band < IEEE80211_NUM_BANDS; band++)
 819                         if (wiphy->bands[band])
 820                                 n_channels += wiphy->bands[band]->n_channels;
 821         }
 822
 823         creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
 824                        n_channels * sizeof(void *),
 825                        GFP_ATOMIC);
 826         if (!creq) {
 827                 err = -ENOMEM;
 828                 goto out;
 829         }
 830
 831         creq->wiphy = wiphy;
 832         creq->dev = dev;
 833         /* SSIDs come after channels */
 834         creq->ssids = (void *)&creq->channels[n_channels];
 835         creq->n_channels = n_channels;
 836         creq->n_ssids = 1;
 837
 838         /* translate "Scan on frequencies" request */
 839         i = 0;
 840         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
 841                 int j;
 842
 843                 if (!wiphy->bands[band])
 844                         continue;
 845
 846                 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
 847                         /* ignore disabled channels */
 848                         if (wiphy->bands[band]->channels[j].flags &
 849                                                 IEEE80211_CHAN_DISABLED)
 850                                 continue;
 851
 852                         /* If we have a wireless request structure and the
 853                          * wireless request specifies frequencies, then search
 854                          * for the matching hardware channel.
 855                          */
 856                         if (wreq && wreq->num_channels) {
 857                                 int k;
 858                                 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
 859                                 for (k = 0; k < wreq->num_channels; k++) {
 860                                         int wext_freq = cfg80211_wext_freq(wiphy, &wreq->channel_list[k]);
 861                                         if (wext_freq == wiphy_freq)
 862                                                 goto wext_freq_found;
 863                                 }
 864                                 goto wext_freq_not_found;
 865                         }
 866
 867                 wext_freq_found:
 868                         creq->channels[i] = &wiphy->bands[band]->channels[j];
 869                         i++;
 870                 wext_freq_not_found: ;
 871                 }
 872         }
 873         /* No channels found? */
 874         if (!i) {
 875                 err = -EINVAL;
 876                 goto out;
 877         }
 878
 879         /* Set real number of channels specified in creq->channels[] */
 880         creq->n_channels = i;
 881
 882         /* translate "Scan for SSID" request */
 883         if (wreq) {
 884                 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
 885                         if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
 886                                 err = -EINVAL;
 887                                 goto out;
 888                         }
 889                         memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
 890                         creq->ssids[0].ssid_len = wreq->essid_len;
 891                 }
 892                 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
 893                         creq->n_ssids = 0;
 894         }
 895
 896         for (i = 0; i < IEEE80211_NUM_BANDS; i++)
 897                 if (wiphy->bands[i])
 898                         creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
 899
 900         rdev->scan_req = creq;
 901         err = rdev->ops->scan(wiphy, dev, creq);
 902         if (err) {
 903                 rdev->scan_req = NULL;
 904                 /* creq will be freed below */
 905         } else {
 906                 nl80211_send_scan_start(rdev, dev);
 907                 /* creq now owned by driver */
 908                 creq = NULL;
 909                 dev_hold(dev);
 910         }
 911  out:
 912         kfree(creq);
 913         cfg80211_unlock_rdev(rdev);
 914         return err;
 915 }
 916 EXPORT_SYMBOL_GPL(cfg80211_wext_siwscan);
 917
 918 static void ieee80211_scan_add_ies(struct iw_request_info *info,
 919                                    struct cfg80211_bss *bss,
 920                                    char **current_ev, char *end_buf)
 921 {
 922         u8 *pos, *end, *next;
 923         struct iw_event iwe;
 924
 925         if (!bss->information_elements ||
 926             !bss->len_information_elements)
 927                 return;
 928
 929         /*
 930          * If needed, fragment the IEs buffer (at IE boundaries) into short
 931          * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
 932          */
 933         pos = bss->information_elements;
 934         end = pos + bss->len_information_elements;
 935
 936         while (end - pos > IW_GENERIC_IE_MAX) {
 937                 next = pos + 2 + pos[1];
 938                 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
 939                         next = next + 2 + next[1];
 940
 941                 memset(&iwe, 0, sizeof(iwe));
 942                 iwe.cmd = IWEVGENIE;
 943                 iwe.u.data.length = next - pos;
 944                 *current_ev = iwe_stream_add_point(info, *current_ev,
 945                                                    end_buf, &iwe, pos);
 946
 947                 pos = next;
 948         }
 949
 950         if (end > pos) {
 951                 memset(&iwe, 0, sizeof(iwe));
 952                 iwe.cmd = IWEVGENIE;
 953                 iwe.u.data.length = end - pos;
 954                 *current_ev = iwe_stream_add_point(info, *current_ev,
 955                                                    end_buf, &iwe, pos);
 956         }
 957 }
 958
 959 static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
 960 {
 961         unsigned long end = jiffies;
 962
 963         if (end >= start)
 964                 return jiffies_to_msecs(end - start);
 965
 966         return jiffies_to_msecs(end + (MAX_JIFFY_OFFSET - start) + 1);
 967 }
 968
 969 static char *
 970 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
 971               struct cfg80211_internal_bss *bss, char *current_ev,
 972               char *end_buf)
 973 {
 974         struct iw_event iwe;
 975         u8 *buf, *cfg, *p;
 976         u8 *ie = bss->pub.information_elements;
 977         int rem = bss->pub.len_information_elements, i, sig;
 978         bool ismesh = false;
 979
 980         memset(&iwe, 0, sizeof(iwe));
 981         iwe.cmd = SIOCGIWAP;
 982         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
 983         memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
 984         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
 985                                           IW_EV_ADDR_LEN);
 986
 987         memset(&iwe, 0, sizeof(iwe));
 988         iwe.cmd = SIOCGIWFREQ;
 989         iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
 990         iwe.u.freq.e = 0;
 991         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
 992                                           IW_EV_FREQ_LEN);
 993
 994         memset(&iwe, 0, sizeof(iwe));
 995         iwe.cmd = SIOCGIWFREQ;
 996         iwe.u.freq.m = bss->pub.channel->center_freq;
 997         iwe.u.freq.e = 6;
 998         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
 999                                           IW_EV_FREQ_LEN);
1000
1001         if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
1002                 memset(&iwe, 0, sizeof(iwe));
1003                 iwe.cmd = IWEVQUAL;
1004                 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
1005                                      IW_QUAL_NOISE_INVALID |
1006                                      IW_QUAL_QUAL_UPDATED;
1007                 switch (wiphy->signal_type) {
1008                 case CFG80211_SIGNAL_TYPE_MBM:
1009                         sig = bss->pub.signal / 100;
1010                         iwe.u.qual.level = sig;
1011                         iwe.u.qual.updated |= IW_QUAL_DBM;
1012                         if (sig < -110)         /* rather bad */
1013                                 sig = -110;
1014                         else if (sig > -40)     /* perfect */
1015                                 sig = -40;
1016                         /* will give a range of 0 .. 70 */
1017                         iwe.u.qual.qual = sig + 110;
1018                         break;
1019                 case CFG80211_SIGNAL_TYPE_UNSPEC:
1020                         iwe.u.qual.level = bss->pub.signal;
1021                         /* will give range 0 .. 100 */
1022                         iwe.u.qual.qual = bss->pub.signal;
1023                         break;
1024                 default:
1025                         /* not reached */
1026                         break;
1027                 }
1028                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1029                                                   &iwe, IW_EV_QUAL_LEN);
1030         }
1031
1032         memset(&iwe, 0, sizeof(iwe));
1033         iwe.cmd = SIOCGIWENCODE;
1034         if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
1035                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
1036         else
1037                 iwe.u.data.flags = IW_ENCODE_DISABLED;
1038         iwe.u.data.length = 0;
1039         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1040                                           &iwe, "");
1041
1042         while (rem >= 2) {
1043                 /* invalid data */
1044                 if (ie[1] > rem - 2)
1045                         break;
1046
1047                 switch (ie[0]) {
1048                 case WLAN_EID_SSID:
1049                         memset(&iwe, 0, sizeof(iwe));
1050                         iwe.cmd = SIOCGIWESSID;
1051                         iwe.u.data.length = ie[1];
1052                         iwe.u.data.flags = 1;
1053                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1054                                                           &iwe, ie + 2);
1055                         break;
1056                 case WLAN_EID_MESH_ID:
1057                         memset(&iwe, 0, sizeof(iwe));
1058                         iwe.cmd = SIOCGIWESSID;
1059                         iwe.u.data.length = ie[1];
1060                         iwe.u.data.flags = 1;
1061                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1062                                                           &iwe, ie + 2);
1063                         break;
1064                 case WLAN_EID_MESH_CONFIG:
1065                         ismesh = true;
1066                         if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
1067                                 break;
1068                         buf = kmalloc(50, GFP_ATOMIC);
1069                         if (!buf)
1070                                 break;
1071                         cfg = ie + 2;
1072                         memset(&iwe, 0, sizeof(iwe));
1073                         iwe.cmd = IWEVCUSTOM;
1074                         sprintf(buf, "Mesh Network Path Selection Protocol ID: "
1075                                 "0x%02X", cfg[0]);
1076                         iwe.u.data.length = strlen(buf);
1077                         current_ev = iwe_stream_add_point(info, current_ev,
1078                                                           end_buf,
1079                                                           &iwe, buf);
1080                         sprintf(buf, "Path Selection Metric ID: 0x%02X",
1081                                 cfg[1]);
1082                         iwe.u.data.length = strlen(buf);
1083                         current_ev = iwe_stream_add_point(info, current_ev,
1084                                                           end_buf,
1085                                                           &iwe, buf);
1086                         sprintf(buf, "Congestion Control Mode ID: 0x%02X",
1087                                 cfg[2]);
1088                         iwe.u.data.length = strlen(buf);
1089                         current_ev = iwe_stream_add_point(info, current_ev,
1090                                                           end_buf,
1091                                                           &iwe, buf);
1092                         sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
1093                         iwe.u.data.length = strlen(buf);
1094                         current_ev = iwe_stream_add_point(info, current_ev,
1095                                                           end_buf,
1096                                                           &iwe, buf);
1097                         sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
1098                         iwe.u.data.length = strlen(buf);
1099                         current_ev = iwe_stream_add_point(info, current_ev,
1100                                                           end_buf,
1101                                                           &iwe, buf);
1102                         sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
1103                         iwe.u.data.length = strlen(buf);
1104                         current_ev = iwe_stream_add_point(info, current_ev,
1105                                                           end_buf,
1106                                                           &iwe, buf);
1107                         sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
1108                         iwe.u.data.length = strlen(buf);
1109                         current_ev = iwe_stream_add_point(info, current_ev,
1110                                                           end_buf,
1111                                                           &iwe, buf);
1112                         kfree(buf);
1113                         break;
1114                 case WLAN_EID_SUPP_RATES:
1115                 case WLAN_EID_EXT_SUPP_RATES:
1116                         /* display all supported rates in readable format */
1117                         p = current_ev + iwe_stream_lcp_len(info);
1118
1119                         memset(&iwe, 0, sizeof(iwe));
1120                         iwe.cmd = SIOCGIWRATE;
1121                         /* Those two flags are ignored... */
1122                         iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
1123
1124                         for (i = 0; i < ie[1]; i++) {
1125                                 iwe.u.bitrate.value =
1126                                         ((ie[i + 2] & 0x7f) * 500000);
1127                                 p = iwe_stream_add_value(info, current_ev, p,
1128                                                 end_buf, &iwe, IW_EV_PARAM_LEN);
1129                         }
1130                         current_ev = p;
1131                         break;
1132                 }
1133                 rem -= ie[1] + 2;
1134                 ie += ie[1] + 2;
1135         }
1136
1137         if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
1138             ismesh) {
1139                 memset(&iwe, 0, sizeof(iwe));
1140                 iwe.cmd = SIOCGIWMODE;
1141                 if (ismesh)
1142                         iwe.u.mode = IW_MODE_MESH;
1143                 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
1144                         iwe.u.mode = IW_MODE_MASTER;
1145                 else
1146                         iwe.u.mode = IW_MODE_ADHOC;
1147                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1148                                                   &iwe, IW_EV_UINT_LEN);
1149         }
1150
1151         buf = kmalloc(30, GFP_ATOMIC);
1152         if (buf) {
1153                 memset(&iwe, 0, sizeof(iwe));
1154                 iwe.cmd = IWEVCUSTOM;
1155                 sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->pub.tsf));
1156                 iwe.u.data.length = strlen(buf);
1157                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1158                                                   &iwe, buf);
1159                 memset(&iwe, 0, sizeof(iwe));
1160                 iwe.cmd = IWEVCUSTOM;
1161                 sprintf(buf, " Last beacon: %ums ago",
1162                         elapsed_jiffies_msecs(bss->ts));
1163                 iwe.u.data.length = strlen(buf);
1164                 current_ev = iwe_stream_add_point(info, current_ev,
1165                                                   end_buf, &iwe, buf);
1166                 kfree(buf);
1167         }
1168
1169         ieee80211_scan_add_ies(info, &bss->pub, &current_ev, end_buf);
1170
1171         return current_ev;
1172 }
1173
1174
1175 static int ieee80211_scan_results(struct cfg80211_registered_device *dev,
1176                                   struct iw_request_info *info,
1177                                   char *buf, size_t len)
1178 {
1179         char *current_ev = buf;
1180         char *end_buf = buf + len;
1181         struct cfg80211_internal_bss *bss;
1182
1183         spin_lock_bh(&dev->bss_lock);
1184         cfg80211_bss_expire(dev);
1185
1186         list_for_each_entry(bss, &dev->bss_list, list) {
1187                 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
1188                         spin_unlock_bh(&dev->bss_lock);
1189                         return -E2BIG;
1190                 }
1191                 current_ev = ieee80211_bss(&dev->wiphy, info, bss,
1192                                            current_ev, end_buf);
1193         }
1194         spin_unlock_bh(&dev->bss_lock);
1195         return current_ev - buf;
1196 }
1197
1198
1199 int cfg80211_wext_giwscan(struct net_device *dev,
1200                           struct iw_request_info *info,
1201                           struct iw_point *data, char *extra)
1202 {
1203         struct cfg80211_registered_device *rdev;
1204         int res;
1205
1206         if (!netif_running(dev))
1207                 return -ENETDOWN;
1208
1209         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1210
1211         if (IS_ERR(rdev))
1212                 return PTR_ERR(rdev);
1213
1214         if (rdev->scan_req) {
1215                 res = -EAGAIN;
1216                 goto out;
1217         }
1218
1219         res = ieee80211_scan_results(rdev, info, extra, data->length);
1220         data->length = 0;
1221         if (res >= 0) {
1222                 data->length = res;
1223                 res = 0;
1224         }
1225
1226  out:
1227         cfg80211_unlock_rdev(rdev);
1228         return res;
1229 }
1230 EXPORT_SYMBOL_GPL(cfg80211_wext_giwscan);
1231 #endif