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         int r;
 263
 264         if (!ie1 && !ie2)
 265                 return 0;
 266         if (!ie1 || !ie2)
 267                 return -1;
 268
 269         r = memcmp(ie1 + 2, ie2 + 2, min(ie1[1], ie2[1]));
 270         if (r == 0 && ie1[1] != ie2[1])
 271                 return ie2[1] - ie1[1];
 272         return r;
 273 }
 274
 275 static bool is_bss(struct cfg80211_bss *a,
 276                    const u8 *bssid,
 277                    const u8 *ssid, size_t ssid_len)
 278 {
 279         const u8 *ssidie;
 280
 281         if (bssid && compare_ether_addr(a->bssid, bssid))
 282                 return false;
 283
 284         if (!ssid)
 285                 return true;
 286
 287         ssidie = cfg80211_find_ie(WLAN_EID_SSID,
 288                                   a->information_elements,
 289                                   a->len_information_elements);
 290         if (!ssidie)
 291                 return false;
 292         if (ssidie[1] != ssid_len)
 293                 return false;
 294         return memcmp(ssidie + 2, ssid, ssid_len) == 0;
 295 }
 296
 297 static bool is_mesh_bss(struct cfg80211_bss *a)
 298 {
 299         const u8 *ie;
 300
 301         if (!WLAN_CAPABILITY_IS_STA_BSS(a->capability))
 302                 return false;
 303
 304         ie = cfg80211_find_ie(WLAN_EID_MESH_ID,
 305                               a->information_elements,
 306                               a->len_information_elements);
 307         if (!ie)
 308                 return false;
 309
 310         ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
 311                               a->information_elements,
 312                               a->len_information_elements);
 313         if (!ie)
 314                 return false;
 315
 316         return true;
 317 }
 318
 319 static bool is_mesh(struct cfg80211_bss *a,
 320                     const u8 *meshid, size_t meshidlen,
 321                     const u8 *meshcfg)
 322 {
 323         const u8 *ie;
 324
 325         if (!WLAN_CAPABILITY_IS_STA_BSS(a->capability))
 326                 return false;
 327
 328         ie = cfg80211_find_ie(WLAN_EID_MESH_ID,
 329                               a->information_elements,
 330                               a->len_information_elements);
 331         if (!ie)
 332                 return false;
 333         if (ie[1] != meshidlen)
 334                 return false;
 335         if (memcmp(ie + 2, meshid, meshidlen))
 336                 return false;
 337
 338         ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
 339                               a->information_elements,
 340                               a->len_information_elements);
 341         if (!ie)
 342                 return false;
 343         if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
 344                 return false;
 345
 346         /*
 347          * Ignore mesh capability (last two bytes of the IE) when
 348          * comparing since that may differ between stations taking
 349          * part in the same mesh.
 350          */
 351         return memcmp(ie + 2, meshcfg,
 352             sizeof(struct ieee80211_meshconf_ie) - 2) == 0;
 353 }
 354
 355 static int cmp_bss(struct cfg80211_bss *a,
 356                    struct cfg80211_bss *b)
 357 {
 358         int r;
 359
 360         if (a->channel != b->channel)
 361                 return b->channel->center_freq - a->channel->center_freq;
 362
 363         if (is_mesh_bss(a) && is_mesh_bss(b)) {
 364                 r = cmp_ies(WLAN_EID_MESH_ID,
 365                             a->information_elements,
 366                             a->len_information_elements,
 367                             b->information_elements,
 368                             b->len_information_elements);
 369                 if (r)
 370                         return r;
 371                 return cmp_ies(WLAN_EID_MESH_CONFIG,
 372                                a->information_elements,
 373                                a->len_information_elements,
 374                                b->information_elements,
 375                                b->len_information_elements);
 376         }
 377
 378         r = memcmp(a->bssid, b->bssid, ETH_ALEN);
 379         if (r)
 380                 return r;
 381
 382         return cmp_ies(WLAN_EID_SSID,
 383                        a->information_elements,
 384                        a->len_information_elements,
 385                        b->information_elements,
 386                        b->len_information_elements);
 387 }
 388
 389 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
 390                                       struct ieee80211_channel *channel,
 391                                       const u8 *bssid,
 392                                       const u8 *ssid, size_t ssid_len,
 393                                       u16 capa_mask, u16 capa_val)
 394 {
 395         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 396         struct cfg80211_internal_bss *bss, *res = NULL;
 397         unsigned long now = jiffies;
 398
 399         spin_lock_bh(&dev->bss_lock);
 400
 401         list_for_each_entry(bss, &dev->bss_list, list) {
 402                 if ((bss->pub.capability & capa_mask) != capa_val)
 403                         continue;
 404                 if (channel && bss->pub.channel != channel)
 405                         continue;
 406                 /* Don't get expired BSS structs */
 407                 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
 408                     !atomic_read(&bss->hold))
 409                         continue;
 410                 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
 411                         res = bss;
 412                         kref_get(&res->ref);
 413                         break;
 414                 }
 415         }
 416
 417         spin_unlock_bh(&dev->bss_lock);
 418         if (!res)
 419                 return NULL;
 420         return &res->pub;
 421 }
 422 EXPORT_SYMBOL(cfg80211_get_bss);
 423
 424 struct cfg80211_bss *cfg80211_get_mesh(struct wiphy *wiphy,
 425                                        struct ieee80211_channel *channel,
 426                                        const u8 *meshid, size_t meshidlen,
 427                                        const u8 *meshcfg)
 428 {
 429         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 430         struct cfg80211_internal_bss *bss, *res = NULL;
 431
 432         spin_lock_bh(&dev->bss_lock);
 433
 434         list_for_each_entry(bss, &dev->bss_list, list) {
 435                 if (channel && bss->pub.channel != channel)
 436                         continue;
 437                 if (is_mesh(&bss->pub, meshid, meshidlen, meshcfg)) {
 438                         res = bss;
 439                         kref_get(&res->ref);
 440                         break;
 441                 }
 442         }
 443
 444         spin_unlock_bh(&dev->bss_lock);
 445         if (!res)
 446                 return NULL;
 447         return &res->pub;
 448 }
 449 EXPORT_SYMBOL(cfg80211_get_mesh);
 450
 451
 452 static void rb_insert_bss(struct cfg80211_registered_device *dev,
 453                           struct cfg80211_internal_bss *bss)
 454 {
 455         struct rb_node **p = &dev->bss_tree.rb_node;
 456         struct rb_node *parent = NULL;
 457         struct cfg80211_internal_bss *tbss;
 458         int cmp;
 459
 460         while (*p) {
 461                 parent = *p;
 462                 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
 463
 464                 cmp = cmp_bss(&bss->pub, &tbss->pub);
 465
 466                 if (WARN_ON(!cmp)) {
 467                         /* will sort of leak this BSS */
 468                         return;
 469                 }
 470
 471                 if (cmp < 0)
 472                         p = &(*p)->rb_left;
 473                 else
 474                         p = &(*p)->rb_right;
 475         }
 476
 477         rb_link_node(&bss->rbn, parent, p);
 478         rb_insert_color(&bss->rbn, &dev->bss_tree);
 479 }
 480
 481 static struct cfg80211_internal_bss *
 482 rb_find_bss(struct cfg80211_registered_device *dev,
 483             struct cfg80211_internal_bss *res)
 484 {
 485         struct rb_node *n = dev->bss_tree.rb_node;
 486         struct cfg80211_internal_bss *bss;
 487         int r;
 488
 489         while (n) {
 490                 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
 491                 r = cmp_bss(&res->pub, &bss->pub);
 492
 493                 if (r == 0)
 494                         return bss;
 495                 else if (r < 0)
 496                         n = n->rb_left;
 497                 else
 498                         n = n->rb_right;
 499         }
 500
 501         return NULL;
 502 }
 503
 504 static struct cfg80211_internal_bss *
 505 cfg80211_bss_update(struct cfg80211_registered_device *dev,
 506                     struct cfg80211_internal_bss *res)
 507 {
 508         struct cfg80211_internal_bss *found = NULL;
 509
 510         /*
 511          * The reference to "res" is donated to this function.
 512          */
 513
 514         if (WARN_ON(!res->pub.channel)) {
 515                 kref_put(&res->ref, bss_release);
 516                 return NULL;
 517         }
 518
 519         res->ts = jiffies;
 520
 521         spin_lock_bh(&dev->bss_lock);
 522
 523         found = rb_find_bss(dev, res);
 524
 525         if (found) {
 526                 found->pub.beacon_interval = res->pub.beacon_interval;
 527                 found->pub.tsf = res->pub.tsf;
 528                 found->pub.signal = res->pub.signal;
 529                 found->pub.capability = res->pub.capability;
 530                 found->ts = res->ts;
 531
 532                 /* Update IEs */
 533                 if (res->pub.proberesp_ies) {
 534                         size_t used = dev->wiphy.bss_priv_size + sizeof(*res);
 535                         size_t ielen = res->pub.len_proberesp_ies;
 536
 537                         if (found->pub.proberesp_ies &&
 538                             !found->proberesp_ies_allocated &&
 539                             ksize(found) >= used + ielen) {
 540                                 memcpy(found->pub.proberesp_ies,
 541                                        res->pub.proberesp_ies, ielen);
 542                                 found->pub.len_proberesp_ies = ielen;
 543                         } else {
 544                                 u8 *ies = found->pub.proberesp_ies;
 545
 546                                 if (found->proberesp_ies_allocated)
 547                                         ies = krealloc(ies, ielen, GFP_ATOMIC);
 548                                 else
 549                                         ies = kmalloc(ielen, GFP_ATOMIC);
 550
 551                                 if (ies) {
 552                                         memcpy(ies, res->pub.proberesp_ies,
 553                                                ielen);
 554                                         found->proberesp_ies_allocated = true;
 555                                         found->pub.proberesp_ies = ies;
 556                                         found->pub.len_proberesp_ies = ielen;
 557                                 }
 558                         }
 559
 560                         /* Override possible earlier Beacon frame IEs */
 561                         found->pub.information_elements =
 562                                 found->pub.proberesp_ies;
 563                         found->pub.len_information_elements =
 564                                 found->pub.len_proberesp_ies;
 565                 }
 566                 if (res->pub.beacon_ies) {
 567                         size_t used = dev->wiphy.bss_priv_size + sizeof(*res);
 568                         size_t ielen = res->pub.len_beacon_ies;
 569                         bool information_elements_is_beacon_ies =
 570                                 (found->pub.information_elements ==
 571                                  found->pub.beacon_ies);
 572
 573                         if (found->pub.beacon_ies &&
 574                             !found->beacon_ies_allocated &&
 575                             ksize(found) >= used + ielen) {
 576                                 memcpy(found->pub.beacon_ies,
 577                                        res->pub.beacon_ies, ielen);
 578                                 found->pub.len_beacon_ies = ielen;
 579                         } else {
 580                                 u8 *ies = found->pub.beacon_ies;
 581
 582                                 if (found->beacon_ies_allocated)
 583                                         ies = krealloc(ies, ielen, GFP_ATOMIC);
 584                                 else
 585                                         ies = kmalloc(ielen, GFP_ATOMIC);
 586
 587                                 if (ies) {
 588                                         memcpy(ies, res->pub.beacon_ies,
 589                                                ielen);
 590                                         found->beacon_ies_allocated = true;
 591                                         found->pub.beacon_ies = ies;
 592                                         found->pub.len_beacon_ies = ielen;
 593                                 }
 594                         }
 595
 596                         /* Override IEs if they were from a beacon before */
 597                         if (information_elements_is_beacon_ies) {
 598                                 found->pub.information_elements =
 599                                         found->pub.beacon_ies;
 600                                 found->pub.len_information_elements =
 601                                         found->pub.len_beacon_ies;
 602                         }
 603                 }
 604
 605                 kref_put(&res->ref, bss_release);
 606         } else {
 607                 /* this "consumes" the reference */
 608                 list_add_tail(&res->list, &dev->bss_list);
 609                 rb_insert_bss(dev, res);
 610                 found = res;
 611         }
 612
 613         dev->bss_generation++;
 614         spin_unlock_bh(&dev->bss_lock);
 615
 616         kref_get(&found->ref);
 617         return found;
 618 }
 619
 620 struct cfg80211_bss*
 621 cfg80211_inform_bss(struct wiphy *wiphy,
 622                     struct ieee80211_channel *channel,
 623                     const u8 *bssid,
 624                     u64 timestamp, u16 capability, u16 beacon_interval,
 625                     const u8 *ie, size_t ielen,
 626                     s32 signal, gfp_t gfp)
 627 {
 628         struct cfg80211_internal_bss *res;
 629         size_t privsz;
 630
 631         if (WARN_ON(!wiphy))
 632                 return NULL;
 633
 634         privsz = wiphy->bss_priv_size;
 635
 636         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
 637                         (signal < 0 || signal > 100)))
 638                 return NULL;
 639
 640         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
 641         if (!res)
 642                 return NULL;
 643
 644         memcpy(res->pub.bssid, bssid, ETH_ALEN);
 645         res->pub.channel = channel;
 646         res->pub.signal = signal;
 647         res->pub.tsf = timestamp;
 648         res->pub.beacon_interval = beacon_interval;
 649         res->pub.capability = capability;
 650         /*
 651          * Since we do not know here whether the IEs are from a Beacon or Probe
 652          * Response frame, we need to pick one of the options and only use it
 653          * with the driver that does not provide the full Beacon/Probe Response
 654          * frame. Use Beacon frame pointer to avoid indicating that this should
 655          * override the information_elements pointer should we have received an
 656          * earlier indication of Probe Response data.
 657          *
 658          * The initial buffer for the IEs is allocated with the BSS entry and
 659          * is located after the private area.
 660          */
 661         res->pub.beacon_ies = (u8 *)res + sizeof(*res) + privsz;
 662         memcpy(res->pub.beacon_ies, ie, ielen);
 663         res->pub.len_beacon_ies = ielen;
 664         res->pub.information_elements = res->pub.beacon_ies;
 665         res->pub.len_information_elements = res->pub.len_beacon_ies;
 666
 667         kref_init(&res->ref);
 668
 669         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res);
 670         if (!res)
 671                 return NULL;
 672
 673         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 674                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 675
 676         /* cfg80211_bss_update gives us a referenced result */
 677         return &res->pub;
 678 }
 679 EXPORT_SYMBOL(cfg80211_inform_bss);
 680
 681 struct cfg80211_bss *
 682 cfg80211_inform_bss_frame(struct wiphy *wiphy,
 683                           struct ieee80211_channel *channel,
 684                           struct ieee80211_mgmt *mgmt, size_t len,
 685                           s32 signal, gfp_t gfp)
 686 {
 687         struct cfg80211_internal_bss *res;
 688         size_t ielen = len - offsetof(struct ieee80211_mgmt,
 689                                       u.probe_resp.variable);
 690         size_t privsz;
 691
 692         if (WARN_ON(!mgmt))
 693                 return NULL;
 694
 695         if (WARN_ON(!wiphy))
 696                 return NULL;
 697
 698         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
 699                     (signal < 0 || signal > 100)))
 700                 return NULL;
 701
 702         if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
 703                 return NULL;
 704
 705         privsz = wiphy->bss_priv_size;
 706
 707         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
 708         if (!res)
 709                 return NULL;
 710
 711         memcpy(res->pub.bssid, mgmt->bssid, ETH_ALEN);
 712         res->pub.channel = channel;
 713         res->pub.signal = signal;
 714         res->pub.tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
 715         res->pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
 716         res->pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
 717         /*
 718          * The initial buffer for the IEs is allocated with the BSS entry and
 719          * is located after the private area.
 720          */
 721         if (ieee80211_is_probe_resp(mgmt->frame_control)) {
 722                 res->pub.proberesp_ies = (u8 *) res + sizeof(*res) + privsz;
 723                 memcpy(res->pub.proberesp_ies, mgmt->u.probe_resp.variable,
 724                        ielen);
 725                 res->pub.len_proberesp_ies = ielen;
 726                 res->pub.information_elements = res->pub.proberesp_ies;
 727                 res->pub.len_information_elements = res->pub.len_proberesp_ies;
 728         } else {
 729                 res->pub.beacon_ies = (u8 *) res + sizeof(*res) + privsz;
 730                 memcpy(res->pub.beacon_ies, mgmt->u.beacon.variable, ielen);
 731                 res->pub.len_beacon_ies = ielen;
 732                 res->pub.information_elements = res->pub.beacon_ies;
 733                 res->pub.len_information_elements = res->pub.len_beacon_ies;
 734         }
 735
 736         kref_init(&res->ref);
 737
 738         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res);
 739         if (!res)
 740                 return NULL;
 741
 742         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 743                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 744
 745         /* cfg80211_bss_update gives us a referenced result */
 746         return &res->pub;
 747 }
 748 EXPORT_SYMBOL(cfg80211_inform_bss_frame);
 749
 750 void cfg80211_put_bss(struct cfg80211_bss *pub)
 751 {
 752         struct cfg80211_internal_bss *bss;
 753
 754         if (!pub)
 755                 return;
 756
 757         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 758         kref_put(&bss->ref, bss_release);
 759 }
 760 EXPORT_SYMBOL(cfg80211_put_bss);
 761
 762 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
 763 {
 764         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 765         struct cfg80211_internal_bss *bss;
 766
 767         if (WARN_ON(!pub))
 768                 return;
 769
 770         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 771
 772         spin_lock_bh(&dev->bss_lock);
 773         if (!list_empty(&bss->list)) {
 774                 __cfg80211_unlink_bss(dev, bss);
 775                 dev->bss_generation++;
 776         }
 777         spin_unlock_bh(&dev->bss_lock);
 778 }
 779 EXPORT_SYMBOL(cfg80211_unlink_bss);
 780
 781 #ifdef CONFIG_CFG80211_WEXT
 782 int cfg80211_wext_siwscan(struct net_device *dev,
 783                           struct iw_request_info *info,
 784                           union iwreq_data *wrqu, char *extra)
 785 {
 786         struct cfg80211_registered_device *rdev;
 787         struct wiphy *wiphy;
 788         struct iw_scan_req *wreq = NULL;
 789         struct cfg80211_scan_request *creq = NULL;
 790         int i, err, n_channels = 0;
 791         enum ieee80211_band band;
 792
 793         if (!netif_running(dev))
 794                 return -ENETDOWN;
 795
 796         if (wrqu->data.length == sizeof(struct iw_scan_req))
 797                 wreq = (struct iw_scan_req *)extra;
 798
 799         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
 800
 801         if (IS_ERR(rdev))
 802                 return PTR_ERR(rdev);
 803
 804         if (rdev->scan_req) {
 805                 err = -EBUSY;
 806                 goto out;
 807         }
 808
 809         wiphy = &rdev->wiphy;
 810
 811         /* Determine number of channels, needed to allocate creq */
 812         if (wreq && wreq->num_channels)
 813                 n_channels = wreq->num_channels;
 814         else {
 815                 for (band = 0; band < IEEE80211_NUM_BANDS; band++)
 816                         if (wiphy->bands[band])
 817                                 n_channels += wiphy->bands[band]->n_channels;
 818         }
 819
 820         creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
 821                        n_channels * sizeof(void *),
 822                        GFP_ATOMIC);
 823         if (!creq) {
 824                 err = -ENOMEM;
 825                 goto out;
 826         }
 827
 828         creq->wiphy = wiphy;
 829         creq->dev = dev;
 830         /* SSIDs come after channels */
 831         creq->ssids = (void *)&creq->channels[n_channels];
 832         creq->n_channels = n_channels;
 833         creq->n_ssids = 1;
 834
 835         /* translate "Scan on frequencies" request */
 836         i = 0;
 837         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
 838                 int j;
 839
 840                 if (!wiphy->bands[band])
 841                         continue;
 842
 843                 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
 844                         /* ignore disabled channels */
 845                         if (wiphy->bands[band]->channels[j].flags &
 846                                                 IEEE80211_CHAN_DISABLED)
 847                                 continue;
 848
 849                         /* If we have a wireless request structure and the
 850                          * wireless request specifies frequencies, then search
 851                          * for the matching hardware channel.
 852                          */
 853                         if (wreq && wreq->num_channels) {
 854                                 int k;
 855                                 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
 856                                 for (k = 0; k < wreq->num_channels; k++) {
 857                                         int wext_freq = cfg80211_wext_freq(wiphy, &wreq->channel_list[k]);
 858                                         if (wext_freq == wiphy_freq)
 859                                                 goto wext_freq_found;
 860                                 }
 861                                 goto wext_freq_not_found;
 862                         }
 863
 864                 wext_freq_found:
 865                         creq->channels[i] = &wiphy->bands[band]->channels[j];
 866                         i++;
 867                 wext_freq_not_found: ;
 868                 }
 869         }
 870         /* No channels found? */
 871         if (!i) {
 872                 err = -EINVAL;
 873                 goto out;
 874         }
 875
 876         /* Set real number of channels specified in creq->channels[] */
 877         creq->n_channels = i;
 878
 879         /* translate "Scan for SSID" request */
 880         if (wreq) {
 881                 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
 882                         if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
 883                                 err = -EINVAL;
 884                                 goto out;
 885                         }
 886                         memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
 887                         creq->ssids[0].ssid_len = wreq->essid_len;
 888                 }
 889                 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
 890                         creq->n_ssids = 0;
 891         }
 892
 893         for (i = 0; i < IEEE80211_NUM_BANDS; i++)
 894                 if (wiphy->bands[i])
 895                         creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
 896
 897         rdev->scan_req = creq;
 898         err = rdev->ops->scan(wiphy, dev, creq);
 899         if (err) {
 900                 rdev->scan_req = NULL;
 901                 /* creq will be freed below */
 902         } else {
 903                 nl80211_send_scan_start(rdev, dev);
 904                 /* creq now owned by driver */
 905                 creq = NULL;
 906                 dev_hold(dev);
 907         }
 908  out:
 909         kfree(creq);
 910         cfg80211_unlock_rdev(rdev);
 911         return err;
 912 }
 913 EXPORT_SYMBOL_GPL(cfg80211_wext_siwscan);
 914
 915 static void ieee80211_scan_add_ies(struct iw_request_info *info,
 916                                    struct cfg80211_bss *bss,
 917                                    char **current_ev, char *end_buf)
 918 {
 919         u8 *pos, *end, *next;
 920         struct iw_event iwe;
 921
 922         if (!bss->information_elements ||
 923             !bss->len_information_elements)
 924                 return;
 925
 926         /*
 927          * If needed, fragment the IEs buffer (at IE boundaries) into short
 928          * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
 929          */
 930         pos = bss->information_elements;
 931         end = pos + bss->len_information_elements;
 932
 933         while (end - pos > IW_GENERIC_IE_MAX) {
 934                 next = pos + 2 + pos[1];
 935                 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
 936                         next = next + 2 + next[1];
 937
 938                 memset(&iwe, 0, sizeof(iwe));
 939                 iwe.cmd = IWEVGENIE;
 940                 iwe.u.data.length = next - pos;
 941                 *current_ev = iwe_stream_add_point(info, *current_ev,
 942                                                    end_buf, &iwe, pos);
 943
 944                 pos = next;
 945         }
 946
 947         if (end > pos) {
 948                 memset(&iwe, 0, sizeof(iwe));
 949                 iwe.cmd = IWEVGENIE;
 950                 iwe.u.data.length = end - pos;
 951                 *current_ev = iwe_stream_add_point(info, *current_ev,
 952                                                    end_buf, &iwe, pos);
 953         }
 954 }
 955
 956 static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
 957 {
 958         unsigned long end = jiffies;
 959
 960         if (end >= start)
 961                 return jiffies_to_msecs(end - start);
 962
 963         return jiffies_to_msecs(end + (MAX_JIFFY_OFFSET - start) + 1);
 964 }
 965
 966 static char *
 967 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
 968               struct cfg80211_internal_bss *bss, char *current_ev,
 969               char *end_buf)
 970 {
 971         struct iw_event iwe;
 972         u8 *buf, *cfg, *p;
 973         u8 *ie = bss->pub.information_elements;
 974         int rem = bss->pub.len_information_elements, i, sig;
 975         bool ismesh = false;
 976
 977         memset(&iwe, 0, sizeof(iwe));
 978         iwe.cmd = SIOCGIWAP;
 979         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
 980         memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
 981         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
 982                                           IW_EV_ADDR_LEN);
 983
 984         memset(&iwe, 0, sizeof(iwe));
 985         iwe.cmd = SIOCGIWFREQ;
 986         iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
 987         iwe.u.freq.e = 0;
 988         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
 989                                           IW_EV_FREQ_LEN);
 990
 991         memset(&iwe, 0, sizeof(iwe));
 992         iwe.cmd = SIOCGIWFREQ;
 993         iwe.u.freq.m = bss->pub.channel->center_freq;
 994         iwe.u.freq.e = 6;
 995         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
 996                                           IW_EV_FREQ_LEN);
 997
 998         if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
 999                 memset(&iwe, 0, sizeof(iwe));
1000                 iwe.cmd = IWEVQUAL;
1001                 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
1002                                      IW_QUAL_NOISE_INVALID |
1003                                      IW_QUAL_QUAL_UPDATED;
1004                 switch (wiphy->signal_type) {
1005                 case CFG80211_SIGNAL_TYPE_MBM:
1006                         sig = bss->pub.signal / 100;
1007                         iwe.u.qual.level = sig;
1008                         iwe.u.qual.updated |= IW_QUAL_DBM;
1009                         if (sig < -110)         /* rather bad */
1010                                 sig = -110;
1011                         else if (sig > -40)     /* perfect */
1012                                 sig = -40;
1013                         /* will give a range of 0 .. 70 */
1014                         iwe.u.qual.qual = sig + 110;
1015                         break;
1016                 case CFG80211_SIGNAL_TYPE_UNSPEC:
1017                         iwe.u.qual.level = bss->pub.signal;
1018                         /* will give range 0 .. 100 */
1019                         iwe.u.qual.qual = bss->pub.signal;
1020                         break;
1021                 default:
1022                         /* not reached */
1023                         break;
1024                 }
1025                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1026                                                   &iwe, IW_EV_QUAL_LEN);
1027         }
1028
1029         memset(&iwe, 0, sizeof(iwe));
1030         iwe.cmd = SIOCGIWENCODE;
1031         if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
1032                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
1033         else
1034                 iwe.u.data.flags = IW_ENCODE_DISABLED;
1035         iwe.u.data.length = 0;
1036         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1037                                           &iwe, "");
1038
1039         while (rem >= 2) {
1040                 /* invalid data */
1041                 if (ie[1] > rem - 2)
1042                         break;
1043
1044                 switch (ie[0]) {
1045                 case WLAN_EID_SSID:
1046                         memset(&iwe, 0, sizeof(iwe));
1047                         iwe.cmd = SIOCGIWESSID;
1048                         iwe.u.data.length = ie[1];
1049                         iwe.u.data.flags = 1;
1050                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1051                                                           &iwe, ie + 2);
1052                         break;
1053                 case WLAN_EID_MESH_ID:
1054                         memset(&iwe, 0, sizeof(iwe));
1055                         iwe.cmd = SIOCGIWESSID;
1056                         iwe.u.data.length = ie[1];
1057                         iwe.u.data.flags = 1;
1058                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1059                                                           &iwe, ie + 2);
1060                         break;
1061                 case WLAN_EID_MESH_CONFIG:
1062                         ismesh = true;
1063                         if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
1064                                 break;
1065                         buf = kmalloc(50, GFP_ATOMIC);
1066                         if (!buf)
1067                                 break;
1068                         cfg = ie + 2;
1069                         memset(&iwe, 0, sizeof(iwe));
1070                         iwe.cmd = IWEVCUSTOM;
1071                         sprintf(buf, "Mesh Network Path Selection Protocol ID: "
1072                                 "0x%02X", cfg[0]);
1073                         iwe.u.data.length = strlen(buf);
1074                         current_ev = iwe_stream_add_point(info, current_ev,
1075                                                           end_buf,
1076                                                           &iwe, buf);
1077                         sprintf(buf, "Path Selection Metric ID: 0x%02X",
1078                                 cfg[1]);
1079                         iwe.u.data.length = strlen(buf);
1080                         current_ev = iwe_stream_add_point(info, current_ev,
1081                                                           end_buf,
1082                                                           &iwe, buf);
1083                         sprintf(buf, "Congestion Control Mode ID: 0x%02X",
1084                                 cfg[2]);
1085                         iwe.u.data.length = strlen(buf);
1086                         current_ev = iwe_stream_add_point(info, current_ev,
1087                                                           end_buf,
1088                                                           &iwe, buf);
1089                         sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
1090                         iwe.u.data.length = strlen(buf);
1091                         current_ev = iwe_stream_add_point(info, current_ev,
1092                                                           end_buf,
1093                                                           &iwe, buf);
1094                         sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
1095                         iwe.u.data.length = strlen(buf);
1096                         current_ev = iwe_stream_add_point(info, current_ev,
1097                                                           end_buf,
1098                                                           &iwe, buf);
1099                         sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
1100                         iwe.u.data.length = strlen(buf);
1101                         current_ev = iwe_stream_add_point(info, current_ev,
1102                                                           end_buf,
1103                                                           &iwe, buf);
1104                         sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
1105                         iwe.u.data.length = strlen(buf);
1106                         current_ev = iwe_stream_add_point(info, current_ev,
1107                                                           end_buf,
1108                                                           &iwe, buf);
1109                         kfree(buf);
1110                         break;
1111                 case WLAN_EID_SUPP_RATES:
1112                 case WLAN_EID_EXT_SUPP_RATES:
1113                         /* display all supported rates in readable format */
1114                         p = current_ev + iwe_stream_lcp_len(info);
1115
1116                         memset(&iwe, 0, sizeof(iwe));
1117                         iwe.cmd = SIOCGIWRATE;
1118                         /* Those two flags are ignored... */
1119                         iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
1120
1121                         for (i = 0; i < ie[1]; i++) {
1122                                 iwe.u.bitrate.value =
1123                                         ((ie[i + 2] & 0x7f) * 500000);
1124                                 p = iwe_stream_add_value(info, current_ev, p,
1125                                                 end_buf, &iwe, IW_EV_PARAM_LEN);
1126                         }
1127                         current_ev = p;
1128                         break;
1129                 }
1130                 rem -= ie[1] + 2;
1131                 ie += ie[1] + 2;
1132         }
1133
1134         if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
1135             ismesh) {
1136                 memset(&iwe, 0, sizeof(iwe));
1137                 iwe.cmd = SIOCGIWMODE;
1138                 if (ismesh)
1139                         iwe.u.mode = IW_MODE_MESH;
1140                 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
1141                         iwe.u.mode = IW_MODE_MASTER;
1142                 else
1143                         iwe.u.mode = IW_MODE_ADHOC;
1144                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1145                                                   &iwe, IW_EV_UINT_LEN);
1146         }
1147
1148         buf = kmalloc(30, GFP_ATOMIC);
1149         if (buf) {
1150                 memset(&iwe, 0, sizeof(iwe));
1151                 iwe.cmd = IWEVCUSTOM;
1152                 sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->pub.tsf));
1153                 iwe.u.data.length = strlen(buf);
1154                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1155                                                   &iwe, buf);
1156                 memset(&iwe, 0, sizeof(iwe));
1157                 iwe.cmd = IWEVCUSTOM;
1158                 sprintf(buf, " Last beacon: %ums ago",
1159                         elapsed_jiffies_msecs(bss->ts));
1160                 iwe.u.data.length = strlen(buf);
1161                 current_ev = iwe_stream_add_point(info, current_ev,
1162                                                   end_buf, &iwe, buf);
1163                 kfree(buf);
1164         }
1165
1166         ieee80211_scan_add_ies(info, &bss->pub, &current_ev, end_buf);
1167
1168         return current_ev;
1169 }
1170
1171
1172 static int ieee80211_scan_results(struct cfg80211_registered_device *dev,
1173                                   struct iw_request_info *info,
1174                                   char *buf, size_t len)
1175 {
1176         char *current_ev = buf;
1177         char *end_buf = buf + len;
1178         struct cfg80211_internal_bss *bss;
1179
1180         spin_lock_bh(&dev->bss_lock);
1181         cfg80211_bss_expire(dev);
1182
1183         list_for_each_entry(bss, &dev->bss_list, list) {
1184                 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
1185                         spin_unlock_bh(&dev->bss_lock);
1186                         return -E2BIG;
1187                 }
1188                 current_ev = ieee80211_bss(&dev->wiphy, info, bss,
1189                                            current_ev, end_buf);
1190         }
1191         spin_unlock_bh(&dev->bss_lock);
1192         return current_ev - buf;
1193 }
1194
1195
1196 int cfg80211_wext_giwscan(struct net_device *dev,
1197                           struct iw_request_info *info,
1198                           struct iw_point *data, char *extra)
1199 {
1200         struct cfg80211_registered_device *rdev;
1201         int res;
1202
1203         if (!netif_running(dev))
1204                 return -ENETDOWN;
1205
1206         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1207
1208         if (IS_ERR(rdev))
1209                 return PTR_ERR(rdev);
1210
1211         if (rdev->scan_req) {
1212                 res = -EAGAIN;
1213                 goto out;
1214         }
1215
1216         res = ieee80211_scan_results(rdev, info, extra, data->length);
1217         data->length = 0;
1218         if (res >= 0) {
1219                 data->length = res;
1220                 res = 0;
1221         }
1222
1223  out:
1224         cfg80211_unlock_rdev(rdev);
1225         return res;
1226 }
1227 EXPORT_SYMBOL_GPL(cfg80211_wext_giwscan);
1228 #endif