net/wireless/core.c

   1 /*
   2  * This is the linux wireless configuration interface.
   3  *
   4  * Copyright 2006-2010          Johannes Berg <johannes@sipsolutions.net>
   5  * Copyright 2013-2014  Intel Mobile Communications GmbH
   6  */
   7
   8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   9
  10 #include <linux/if.h>
  11 #include <linux/module.h>
  12 #include <linux/err.h>
  13 #include <linux/list.h>
  14 #include <linux/slab.h>
  15 #include <linux/nl80211.h>
  16 #include <linux/debugfs.h>
  17 #include <linux/notifier.h>
  18 #include <linux/device.h>
  19 #include <linux/etherdevice.h>
  20 #include <linux/rtnetlink.h>
  21 #include <linux/sched.h>
  22 #include <net/genetlink.h>
  23 #include <net/cfg80211.h>
  24 #include "nl80211.h"
  25 #include "core.h"
  26 #include "sysfs.h"
  27 #include "debugfs.h"
  28 #include "wext-compat.h"
  29 #include "rdev-ops.h"
  30
  31 /* name for sysfs, %d is appended */
  32 #define PHY_NAME "phy"
  33
  34 MODULE_AUTHOR("Johannes Berg");
  35 MODULE_LICENSE("GPL");
  36 MODULE_DESCRIPTION("wireless configuration support");
  37 MODULE_ALIAS_GENL_FAMILY(NL80211_GENL_NAME);
  38
  39 /* RCU-protected (and RTNL for writers) */
  40 LIST_HEAD(cfg80211_rdev_list);
  41 int cfg80211_rdev_list_generation;
  42
  43 /* for debugfs */
  44 static struct dentry *ieee80211_debugfs_dir;
  45
  46 /* for the cleanup, scan and event works */
  47 struct workqueue_struct *cfg80211_wq;
  48
  49 static bool cfg80211_disable_40mhz_24ghz;
  50 module_param(cfg80211_disable_40mhz_24ghz, bool, 0644);
  51 MODULE_PARM_DESC(cfg80211_disable_40mhz_24ghz,
  52                  "Disable 40MHz support in the 2.4GHz band");
  53
  54 struct cfg80211_registered_device *cfg80211_rdev_by_wiphy_idx(int wiphy_idx)
  55 {
  56         struct cfg80211_registered_device *result = NULL, *rdev;
  57
  58         ASSERT_RTNL();
  59
  60         list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
  61                 if (rdev->wiphy_idx == wiphy_idx) {
  62                         result = rdev;
  63                         break;
  64                 }
  65         }
  66
  67         return result;
  68 }
  69
  70 int get_wiphy_idx(struct wiphy *wiphy)
  71 {
  72         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
  73
  74         return rdev->wiphy_idx;
  75 }
  76
  77 struct wiphy *wiphy_idx_to_wiphy(int wiphy_idx)
  78 {
  79         struct cfg80211_registered_device *rdev;
  80
  81         ASSERT_RTNL();
  82
  83         rdev = cfg80211_rdev_by_wiphy_idx(wiphy_idx);
  84         if (!rdev)
  85                 return NULL;
  86         return &rdev->wiphy;
  87 }
  88
  89 static int cfg80211_dev_check_name(struct cfg80211_registered_device *rdev,
  90                                    const char *newname)
  91 {
  92         struct cfg80211_registered_device *rdev2;
  93         int wiphy_idx, taken = -1, digits;
  94
  95         ASSERT_RTNL();
  96
  97         /* prohibit calling the thing phy%d when %d is not its number */
  98         sscanf(newname, PHY_NAME "%d%n", &wiphy_idx, &taken);
  99         if (taken == strlen(newname) && wiphy_idx != rdev->wiphy_idx) {
 100                 /* count number of places needed to print wiphy_idx */
 101                 digits = 1;
 102                 while (wiphy_idx /= 10)
 103                         digits++;
 104                 /*
 105                  * deny the name if it is phy<idx> where <idx> is printed
 106                  * without leading zeroes. taken == strlen(newname) here
 107                  */
 108                 if (taken == strlen(PHY_NAME) + digits)
 109                         return -EINVAL;
 110         }
 111
 112         /* Ensure another device does not already have this name. */
 113         list_for_each_entry(rdev2, &cfg80211_rdev_list, list)
 114                 if (strcmp(newname, wiphy_name(&rdev2->wiphy)) == 0)
 115                         return -EINVAL;
 116
 117         return 0;
 118 }
 119
 120 int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
 121                         char *newname)
 122 {
 123         int result;
 124
 125         ASSERT_RTNL();
 126
 127         /* Ignore nop renames */
 128         if (strcmp(newname, wiphy_name(&rdev->wiphy)) == 0)
 129                 return 0;
 130
 131         result = cfg80211_dev_check_name(rdev, newname);
 132         if (result < 0)
 133                 return result;
 134
 135         result = device_rename(&rdev->wiphy.dev, newname);
 136         if (result)
 137                 return result;
 138
 139         if (rdev->wiphy.debugfsdir &&
 140             !debugfs_rename(rdev->wiphy.debugfsdir->d_parent,
 141                             rdev->wiphy.debugfsdir,
 142                             rdev->wiphy.debugfsdir->d_parent,
 143                             newname))
 144                 pr_err("failed to rename debugfs dir to %s!\n", newname);
 145
 146         nl80211_notify_wiphy(rdev, NL80211_CMD_NEW_WIPHY);
 147
 148         return 0;
 149 }
 150
 151 int cfg80211_switch_netns(struct cfg80211_registered_device *rdev,
 152                           struct net *net)
 153 {
 154         struct wireless_dev *wdev;
 155         int err = 0;
 156
 157         if (!(rdev->wiphy.flags & WIPHY_FLAG_NETNS_OK))
 158                 return -EOPNOTSUPP;
 159
 160         list_for_each_entry(wdev, &rdev->wdev_list, list) {
 161                 if (!wdev->netdev)
 162                         continue;
 163                 wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
 164                 err = dev_change_net_namespace(wdev->netdev, net, "wlan%d");
 165                 if (err)
 166                         break;
 167                 wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
 168         }
 169
 170         if (err) {
 171                 /* failed -- clean up to old netns */
 172                 net = wiphy_net(&rdev->wiphy);
 173
 174                 list_for_each_entry_continue_reverse(wdev, &rdev->wdev_list,
 175                                                      list) {
 176                         if (!wdev->netdev)
 177                                 continue;
 178                         wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
 179                         err = dev_change_net_namespace(wdev->netdev, net,
 180                                                         "wlan%d");
 181                         WARN_ON(err);
 182                         wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
 183                 }
 184
 185                 return err;
 186         }
 187
 188         wiphy_net_set(&rdev->wiphy, net);
 189
 190         err = device_rename(&rdev->wiphy.dev, dev_name(&rdev->wiphy.dev));
 191         WARN_ON(err);
 192
 193         return 0;
 194 }
 195
 196 static void cfg80211_rfkill_poll(struct rfkill *rfkill, void *data)
 197 {
 198         struct cfg80211_registered_device *rdev = data;
 199
 200         rdev_rfkill_poll(rdev);
 201 }
 202
 203 void cfg80211_stop_p2p_device(struct cfg80211_registered_device *rdev,
 204                               struct wireless_dev *wdev)
 205 {
 206         ASSERT_RTNL();
 207
 208         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_P2P_DEVICE))
 209                 return;
 210
 211         if (!wdev->p2p_started)
 212                 return;
 213
 214         rdev_stop_p2p_device(rdev, wdev);
 215         wdev->p2p_started = false;
 216
 217         rdev->opencount--;
 218
 219         if (rdev->scan_req && rdev->scan_req->wdev == wdev) {
 220                 if (WARN_ON(!rdev->scan_req->notified))
 221                         rdev->scan_req->aborted = true;
 222                 ___cfg80211_scan_done(rdev, false);
 223         }
 224 }
 225
 226 void cfg80211_shutdown_all_interfaces(struct wiphy *wiphy)
 227 {
 228         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 229         struct wireless_dev *wdev;
 230
 231         ASSERT_RTNL();
 232
 233         list_for_each_entry(wdev, &rdev->wdev_list, list) {
 234                 if (wdev->netdev) {
 235                         dev_close(wdev->netdev);
 236                         continue;
 237                 }
 238                 /* otherwise, check iftype */
 239                 switch (wdev->iftype) {
 240                 case NL80211_IFTYPE_P2P_DEVICE:
 241                         cfg80211_stop_p2p_device(rdev, wdev);
 242                         break;
 243                 default:
 244                         break;
 245                 }
 246         }
 247 }
 248 EXPORT_SYMBOL_GPL(cfg80211_shutdown_all_interfaces);
 249
 250 static int cfg80211_rfkill_set_block(void *data, bool blocked)
 251 {
 252         struct cfg80211_registered_device *rdev = data;
 253
 254         if (!blocked)
 255                 return 0;
 256
 257         rtnl_lock();
 258         cfg80211_shutdown_all_interfaces(&rdev->wiphy);
 259         rtnl_unlock();
 260
 261         return 0;
 262 }
 263
 264 static void cfg80211_rfkill_sync_work(struct work_struct *work)
 265 {
 266         struct cfg80211_registered_device *rdev;
 267
 268         rdev = container_of(work, struct cfg80211_registered_device, rfkill_sync);
 269         cfg80211_rfkill_set_block(rdev, rfkill_blocked(rdev->rfkill));
 270 }
 271
 272 static void cfg80211_event_work(struct work_struct *work)
 273 {
 274         struct cfg80211_registered_device *rdev;
 275
 276         rdev = container_of(work, struct cfg80211_registered_device,
 277                             event_work);
 278
 279         rtnl_lock();
 280         cfg80211_process_rdev_events(rdev);
 281         rtnl_unlock();
 282 }
 283
 284 void cfg80211_destroy_ifaces(struct cfg80211_registered_device *rdev)
 285 {
 286         struct cfg80211_iface_destroy *item;
 287
 288         ASSERT_RTNL();
 289
 290         spin_lock_irq(&rdev->destroy_list_lock);
 291         while ((item = list_first_entry_or_null(&rdev->destroy_list,
 292                                                 struct cfg80211_iface_destroy,
 293                                                 list))) {
 294                 struct wireless_dev *wdev, *tmp;
 295                 u32 nlportid = item->nlportid;
 296
 297                 list_del(&item->list);
 298                 kfree(item);
 299                 spin_unlock_irq(&rdev->destroy_list_lock);
 300
 301                 list_for_each_entry_safe(wdev, tmp, &rdev->wdev_list, list) {
 302                         if (nlportid == wdev->owner_nlportid)
 303                                 rdev_del_virtual_intf(rdev, wdev);
 304                 }
 305
 306                 spin_lock_irq(&rdev->destroy_list_lock);
 307         }
 308         spin_unlock_irq(&rdev->destroy_list_lock);
 309 }
 310
 311 static void cfg80211_destroy_iface_wk(struct work_struct *work)
 312 {
 313         struct cfg80211_registered_device *rdev;
 314
 315         rdev = container_of(work, struct cfg80211_registered_device,
 316                             destroy_work);
 317
 318         rtnl_lock();
 319         cfg80211_destroy_ifaces(rdev);
 320         rtnl_unlock();
 321 }
 322
 323 /* exported functions */
 324
 325 struct wiphy *wiphy_new_nm(const struct cfg80211_ops *ops, int sizeof_priv,
 326                            const char *requested_name)
 327 {
 328         static atomic_t wiphy_counter = ATOMIC_INIT(0);
 329
 330         struct cfg80211_registered_device *rdev;
 331         int alloc_size;
 332
 333         WARN_ON(ops->add_key && (!ops->del_key || !ops->set_default_key));
 334         WARN_ON(ops->auth && (!ops->assoc || !ops->deauth || !ops->disassoc));
 335         WARN_ON(ops->connect && !ops->disconnect);
 336         WARN_ON(ops->join_ibss && !ops->leave_ibss);
 337         WARN_ON(ops->add_virtual_intf && !ops->del_virtual_intf);
 338         WARN_ON(ops->add_station && !ops->del_station);
 339         WARN_ON(ops->add_mpath && !ops->del_mpath);
 340         WARN_ON(ops->join_mesh && !ops->leave_mesh);
 341
 342         alloc_size = sizeof(*rdev) + sizeof_priv;
 343
 344         rdev = kzalloc(alloc_size, GFP_KERNEL);
 345         if (!rdev)
 346                 return NULL;
 347
 348         rdev->ops = ops;
 349
 350         rdev->wiphy_idx = atomic_inc_return(&wiphy_counter);
 351
 352         if (unlikely(rdev->wiphy_idx < 0)) {
 353                 /* ugh, wrapped! */
 354                 atomic_dec(&wiphy_counter);
 355                 kfree(rdev);
 356                 return NULL;
 357         }
 358
 359         /* atomic_inc_return makes it start at 1, make it start at 0 */
 360         rdev->wiphy_idx--;
 361
 362         /* give it a proper name */
 363         if (requested_name && requested_name[0]) {
 364                 int rv;
 365
 366                 rtnl_lock();
 367                 rv = cfg80211_dev_check_name(rdev, requested_name);
 368
 369                 if (rv < 0) {
 370                         rtnl_unlock();
 371                         goto use_default_name;
 372                 }
 373
 374                 rv = dev_set_name(&rdev->wiphy.dev, "%s", requested_name);
 375                 rtnl_unlock();
 376                 if (rv)
 377                         goto use_default_name;
 378         } else {
 379 use_default_name:
 380                 /* NOTE:  This is *probably* safe w/out holding rtnl because of
 381                  * the restrictions on phy names.  Probably this call could
 382                  * fail if some other part of the kernel (re)named a device
 383                  * phyX.  But, might should add some locking and check return
 384                  * value, and use a different name if this one exists?
 385                  */
 386                 dev_set_name(&rdev->wiphy.dev, PHY_NAME "%d", rdev->wiphy_idx);
 387         }
 388
 389         INIT_LIST_HEAD(&rdev->wdev_list);
 390         INIT_LIST_HEAD(&rdev->beacon_registrations);
 391         spin_lock_init(&rdev->beacon_registrations_lock);
 392         spin_lock_init(&rdev->bss_lock);
 393         INIT_LIST_HEAD(&rdev->bss_list);
 394         INIT_WORK(&rdev->scan_done_wk, __cfg80211_scan_done);
 395         INIT_WORK(&rdev->sched_scan_results_wk, __cfg80211_sched_scan_results);
 396         INIT_DELAYED_WORK(&rdev->dfs_update_channels_wk,
 397                           cfg80211_dfs_channels_update_work);
 398 #ifdef CONFIG_CFG80211_WEXT
 399         rdev->wiphy.wext = &cfg80211_wext_handler;
 400 #endif
 401
 402         device_initialize(&rdev->wiphy.dev);
 403         rdev->wiphy.dev.class = &ieee80211_class;
 404         rdev->wiphy.dev.platform_data = rdev;
 405
 406         INIT_LIST_HEAD(&rdev->destroy_list);
 407         spin_lock_init(&rdev->destroy_list_lock);
 408         INIT_WORK(&rdev->destroy_work, cfg80211_destroy_iface_wk);
 409
 410 #ifdef CONFIG_CFG80211_DEFAULT_PS
 411         rdev->wiphy.flags |= WIPHY_FLAG_PS_ON_BY_DEFAULT;
 412 #endif
 413
 414         wiphy_net_set(&rdev->wiphy, &init_net);
 415
 416         rdev->rfkill_ops.set_block = cfg80211_rfkill_set_block;
 417         rdev->rfkill = rfkill_alloc(dev_name(&rdev->wiphy.dev),
 418                                    &rdev->wiphy.dev, RFKILL_TYPE_WLAN,
 419                                    &rdev->rfkill_ops, rdev);
 420
 421         if (!rdev->rfkill) {
 422                 kfree(rdev);
 423                 return NULL;
 424         }
 425
 426         INIT_WORK(&rdev->rfkill_sync, cfg80211_rfkill_sync_work);
 427         INIT_WORK(&rdev->conn_work, cfg80211_conn_work);
 428         INIT_WORK(&rdev->event_work, cfg80211_event_work);
 429
 430         init_waitqueue_head(&rdev->dev_wait);
 431
 432         /*
 433          * Initialize wiphy parameters to IEEE 802.11 MIB default values.
 434          * Fragmentation and RTS threshold are disabled by default with the
 435          * special -1 value.
 436          */
 437         rdev->wiphy.retry_short = 7;
 438         rdev->wiphy.retry_long = 4;
 439         rdev->wiphy.frag_threshold = (u32) -1;
 440         rdev->wiphy.rts_threshold = (u32) -1;
 441         rdev->wiphy.coverage_class = 0;
 442
 443         rdev->wiphy.max_num_csa_counters = 1;
 444
 445         return &rdev->wiphy;
 446 }
 447 EXPORT_SYMBOL(wiphy_new_nm);
 448
 449 static int wiphy_verify_combinations(struct wiphy *wiphy)
 450 {
 451         const struct ieee80211_iface_combination *c;
 452         int i, j;
 453
 454         for (i = 0; i < wiphy->n_iface_combinations; i++) {
 455                 u32 cnt = 0;
 456                 u16 all_iftypes = 0;
 457
 458                 c = &wiphy->iface_combinations[i];
 459
 460                 /*
 461                  * Combinations with just one interface aren't real,
 462                  * however we make an exception for DFS.
 463                  */
 464                 if (WARN_ON((c->max_interfaces < 2) && !c->radar_detect_widths))
 465                         return -EINVAL;
 466
 467                 /* Need at least one channel */
 468                 if (WARN_ON(!c->num_different_channels))
 469                         return -EINVAL;
 470
 471                 /*
 472                  * Put a sane limit on maximum number of different
 473                  * channels to simplify channel accounting code.
 474                  */
 475                 if (WARN_ON(c->num_different_channels >
 476                                 CFG80211_MAX_NUM_DIFFERENT_CHANNELS))
 477                         return -EINVAL;
 478
 479                 /* DFS only works on one channel. */
 480                 if (WARN_ON(c->radar_detect_widths &&
 481                             (c->num_different_channels > 1)))
 482                         return -EINVAL;
 483
 484                 if (WARN_ON(!c->n_limits))
 485                         return -EINVAL;
 486
 487                 for (j = 0; j < c->n_limits; j++) {
 488                         u16 types = c->limits[j].types;
 489
 490                         /* interface types shouldn't overlap */
 491                         if (WARN_ON(types & all_iftypes))
 492                                 return -EINVAL;
 493                         all_iftypes |= types;
 494
 495                         if (WARN_ON(!c->limits[j].max))
 496                                 return -EINVAL;
 497
 498                         /* Shouldn't list software iftypes in combinations! */
 499                         if (WARN_ON(wiphy->software_iftypes & types))
 500                                 return -EINVAL;
 501
 502                         /* Only a single P2P_DEVICE can be allowed */
 503                         if (WARN_ON(types & BIT(NL80211_IFTYPE_P2P_DEVICE) &&
 504                                     c->limits[j].max > 1))
 505                                 return -EINVAL;
 506
 507                         cnt += c->limits[j].max;
 508                         /*
 509                          * Don't advertise an unsupported type
 510                          * in a combination.
 511                          */
 512                         if (WARN_ON((wiphy->interface_modes & types) != types))
 513                                 return -EINVAL;
 514                 }
 515
 516                 /* You can't even choose that many! */
 517                 if (WARN_ON(cnt < c->max_interfaces))
 518                         return -EINVAL;
 519         }
 520
 521         return 0;
 522 }
 523
 524 int wiphy_register(struct wiphy *wiphy)
 525 {
 526         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 527         int res;
 528         enum ieee80211_band band;
 529         struct ieee80211_supported_band *sband;
 530         bool have_band = false;
 531         int i;
 532         u16 ifmodes = wiphy->interface_modes;
 533
 534 #ifdef CONFIG_PM
 535         if (WARN_ON(wiphy->wowlan &&
 536                     (wiphy->wowlan->flags & WIPHY_WOWLAN_GTK_REKEY_FAILURE) &&
 537                     !(wiphy->wowlan->flags & WIPHY_WOWLAN_SUPPORTS_GTK_REKEY)))
 538                 return -EINVAL;
 539         if (WARN_ON(wiphy->wowlan &&
 540                     !wiphy->wowlan->flags && !wiphy->wowlan->n_patterns &&
 541                     !wiphy->wowlan->tcp))
 542                 return -EINVAL;
 543 #endif
 544         if (WARN_ON((wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH) &&
 545                     (!rdev->ops->tdls_channel_switch ||
 546                      !rdev->ops->tdls_cancel_channel_switch)))
 547                 return -EINVAL;
 548
 549         /*
 550          * if a wiphy has unsupported modes for regulatory channel enforcement,
 551          * opt-out of enforcement checking
 552          */
 553         if (wiphy->interface_modes & ~(BIT(NL80211_IFTYPE_STATION) |
 554                                        BIT(NL80211_IFTYPE_P2P_CLIENT) |
 555                                        BIT(NL80211_IFTYPE_AP) |
 556                                        BIT(NL80211_IFTYPE_P2P_GO) |
 557                                        BIT(NL80211_IFTYPE_ADHOC) |
 558                                        BIT(NL80211_IFTYPE_P2P_DEVICE) |
 559                                        BIT(NL80211_IFTYPE_AP_VLAN) |
 560                                        BIT(NL80211_IFTYPE_MONITOR)))
 561                 wiphy->regulatory_flags |= REGULATORY_IGNORE_STALE_KICKOFF;
 562
 563         if (WARN_ON(wiphy->coalesce &&
 564                     (!wiphy->coalesce->n_rules ||
 565                      !wiphy->coalesce->n_patterns) &&
 566                     (!wiphy->coalesce->pattern_min_len ||
 567                      wiphy->coalesce->pattern_min_len >
 568                         wiphy->coalesce->pattern_max_len)))
 569                 return -EINVAL;
 570
 571         if (WARN_ON(wiphy->ap_sme_capa &&
 572                     !(wiphy->flags & WIPHY_FLAG_HAVE_AP_SME)))
 573                 return -EINVAL;
 574
 575         if (WARN_ON(wiphy->addresses && !wiphy->n_addresses))
 576                 return -EINVAL;
 577
 578         if (WARN_ON(wiphy->addresses &&
 579                     !is_zero_ether_addr(wiphy->perm_addr) &&
 580                     memcmp(wiphy->perm_addr, wiphy->addresses[0].addr,
 581                            ETH_ALEN)))
 582                 return -EINVAL;
 583
 584         if (WARN_ON(wiphy->max_acl_mac_addrs &&
 585                     (!(wiphy->flags & WIPHY_FLAG_HAVE_AP_SME) ||
 586                      !rdev->ops->set_mac_acl)))
 587                 return -EINVAL;
 588
 589         if (wiphy->addresses)
 590                 memcpy(wiphy->perm_addr, wiphy->addresses[0].addr, ETH_ALEN);
 591
 592         /* sanity check ifmodes */
 593         WARN_ON(!ifmodes);
 594         ifmodes &= ((1 << NUM_NL80211_IFTYPES) - 1) & ~1;
 595         if (WARN_ON(ifmodes != wiphy->interface_modes))
 596                 wiphy->interface_modes = ifmodes;
 597
 598         res = wiphy_verify_combinations(wiphy);
 599         if (res)
 600                 return res;
 601
 602         /* sanity check supported bands/channels */
 603         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
 604                 sband = wiphy->bands[band];
 605                 if (!sband)
 606                         continue;
 607
 608                 sband->band = band;
 609                 if (WARN_ON(!sband->n_channels))
 610                         return -EINVAL;
 611                 /*
 612                  * on 60gHz band, there are no legacy rates, so
 613                  * n_bitrates is 0
 614                  */
 615                 if (WARN_ON(band != IEEE80211_BAND_60GHZ &&
 616                             !sband->n_bitrates))
 617                         return -EINVAL;
 618
 619                 /*
 620                  * Since cfg80211_disable_40mhz_24ghz is global, we can
 621                  * modify the sband's ht data even if the driver uses a
 622                  * global structure for that.
 623                  */
 624                 if (cfg80211_disable_40mhz_24ghz &&
 625                     band == IEEE80211_BAND_2GHZ &&
 626                     sband->ht_cap.ht_supported) {
 627                         sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 628                         sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SGI_40;
 629                 }
 630
 631                 /*
 632                  * Since we use a u32 for rate bitmaps in
 633                  * ieee80211_get_response_rate, we cannot
 634                  * have more than 32 legacy rates.
 635                  */
 636                 if (WARN_ON(sband->n_bitrates > 32))
 637                         return -EINVAL;
 638
 639                 for (i = 0; i < sband->n_channels; i++) {
 640                         sband->channels[i].orig_flags =
 641                                 sband->channels[i].flags;
 642                         sband->channels[i].orig_mag = INT_MAX;
 643                         sband->channels[i].orig_mpwr =
 644                                 sband->channels[i].max_power;
 645                         sband->channels[i].band = band;
 646                 }
 647
 648                 have_band = true;
 649         }
 650
 651         if (!have_band) {
 652                 WARN_ON(1);
 653                 return -EINVAL;
 654         }
 655
 656 #ifdef CONFIG_PM
 657         if (WARN_ON(rdev->wiphy.wowlan && rdev->wiphy.wowlan->n_patterns &&
 658                     (!rdev->wiphy.wowlan->pattern_min_len ||
 659                      rdev->wiphy.wowlan->pattern_min_len >
 660                                 rdev->wiphy.wowlan->pattern_max_len)))
 661                 return -EINVAL;
 662 #endif
 663
 664         /* check and set up bitrates */
 665         ieee80211_set_bitrate_flags(wiphy);
 666
 667         rdev->wiphy.features |= NL80211_FEATURE_SCAN_FLUSH;
 668
 669         rtnl_lock();
 670         res = device_add(&rdev->wiphy.dev);
 671         if (res) {
 672                 rtnl_unlock();
 673                 return res;
 674         }
 675
 676         /* set up regulatory info */
 677         wiphy_regulatory_register(wiphy);
 678
 679         list_add_rcu(&rdev->list, &cfg80211_rdev_list);
 680         cfg80211_rdev_list_generation++;
 681
 682         /* add to debugfs */
 683         rdev->wiphy.debugfsdir =
 684                 debugfs_create_dir(wiphy_name(&rdev->wiphy),
 685                                    ieee80211_debugfs_dir);
 686         if (IS_ERR(rdev->wiphy.debugfsdir))
 687                 rdev->wiphy.debugfsdir = NULL;
 688
 689         cfg80211_debugfs_rdev_add(rdev);
 690         nl80211_notify_wiphy(rdev, NL80211_CMD_NEW_WIPHY);
 691
 692         if (wiphy->regulatory_flags & REGULATORY_CUSTOM_REG) {
 693                 struct regulatory_request request;
 694
 695                 request.wiphy_idx = get_wiphy_idx(wiphy);
 696                 request.initiator = NL80211_REGDOM_SET_BY_DRIVER;
 697                 request.alpha2[0] = '9';
 698                 request.alpha2[1] = '9';
 699
 700                 nl80211_send_reg_change_event(&request);
 701         }
 702
 703         rdev->wiphy.registered = true;
 704         rtnl_unlock();
 705
 706         res = rfkill_register(rdev->rfkill);
 707         if (res) {
 708                 rfkill_destroy(rdev->rfkill);
 709                 rdev->rfkill = NULL;
 710                 wiphy_unregister(&rdev->wiphy);
 711                 return res;
 712         }
 713
 714         return 0;
 715 }
 716 EXPORT_SYMBOL(wiphy_register);
 717
 718 void wiphy_rfkill_start_polling(struct wiphy *wiphy)
 719 {
 720         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 721
 722         if (!rdev->ops->rfkill_poll)
 723                 return;
 724         rdev->rfkill_ops.poll = cfg80211_rfkill_poll;
 725         rfkill_resume_polling(rdev->rfkill);
 726 }
 727 EXPORT_SYMBOL(wiphy_rfkill_start_polling);
 728
 729 void wiphy_rfkill_stop_polling(struct wiphy *wiphy)
 730 {
 731         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 732
 733         rfkill_pause_polling(rdev->rfkill);
 734 }
 735 EXPORT_SYMBOL(wiphy_rfkill_stop_polling);
 736
 737 void wiphy_unregister(struct wiphy *wiphy)
 738 {
 739         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 740
 741         wait_event(rdev->dev_wait, ({
 742                 int __count;
 743                 rtnl_lock();
 744                 __count = rdev->opencount;
 745                 rtnl_unlock();
 746                 __count == 0; }));
 747
 748         if (rdev->rfkill)
 749                 rfkill_unregister(rdev->rfkill);
 750
 751         rtnl_lock();
 752         nl80211_notify_wiphy(rdev, NL80211_CMD_DEL_WIPHY);
 753         rdev->wiphy.registered = false;
 754
 755         WARN_ON(!list_empty(&rdev->wdev_list));
 756
 757         /*
 758          * First remove the hardware from everywhere, this makes
 759          * it impossible to find from userspace.
 760          */
 761         debugfs_remove_recursive(rdev->wiphy.debugfsdir);
 762         list_del_rcu(&rdev->list);
 763         synchronize_rcu();
 764
 765         /*
 766          * If this device got a regulatory hint tell core its
 767          * free to listen now to a new shiny device regulatory hint
 768          */
 769         wiphy_regulatory_deregister(wiphy);
 770
 771         cfg80211_rdev_list_generation++;
 772         device_del(&rdev->wiphy.dev);
 773
 774         rtnl_unlock();
 775
 776         flush_work(&rdev->scan_done_wk);
 777         cancel_work_sync(&rdev->conn_work);
 778         flush_work(&rdev->event_work);
 779         cancel_delayed_work_sync(&rdev->dfs_update_channels_wk);
 780         flush_work(&rdev->destroy_work);
 781
 782 #ifdef CONFIG_PM
 783         if (rdev->wiphy.wowlan_config && rdev->ops->set_wakeup)
 784                 rdev_set_wakeup(rdev, false);
 785 #endif
 786         cfg80211_rdev_free_wowlan(rdev);
 787         cfg80211_rdev_free_coalesce(rdev);
 788 }
 789 EXPORT_SYMBOL(wiphy_unregister);
 790
 791 void cfg80211_dev_free(struct cfg80211_registered_device *rdev)
 792 {
 793         struct cfg80211_internal_bss *scan, *tmp;
 794         struct cfg80211_beacon_registration *reg, *treg;
 795         rfkill_destroy(rdev->rfkill);
 796         list_for_each_entry_safe(reg, treg, &rdev->beacon_registrations, list) {
 797                 list_del(&reg->list);
 798                 kfree(reg);
 799         }
 800         list_for_each_entry_safe(scan, tmp, &rdev->bss_list, list)
 801                 cfg80211_put_bss(&rdev->wiphy, &scan->pub);
 802         kfree(rdev);
 803 }
 804
 805 void wiphy_free(struct wiphy *wiphy)
 806 {
 807         put_device(&wiphy->dev);
 808 }
 809 EXPORT_SYMBOL(wiphy_free);
 810
 811 void wiphy_rfkill_set_hw_state(struct wiphy *wiphy, bool blocked)
 812 {
 813         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 814
 815         if (rfkill_set_hw_state(rdev->rfkill, blocked))
 816                 schedule_work(&rdev->rfkill_sync);
 817 }
 818 EXPORT_SYMBOL(wiphy_rfkill_set_hw_state);
 819
 820 void cfg80211_unregister_wdev(struct wireless_dev *wdev)
 821 {
 822         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
 823
 824         ASSERT_RTNL();
 825
 826         if (WARN_ON(wdev->netdev))
 827                 return;
 828
 829         list_del_rcu(&wdev->list);
 830         rdev->devlist_generation++;
 831
 832         switch (wdev->iftype) {
 833         case NL80211_IFTYPE_P2P_DEVICE:
 834                 cfg80211_stop_p2p_device(rdev, wdev);
 835                 break;
 836         default:
 837                 WARN_ON_ONCE(1);
 838                 break;
 839         }
 840 }
 841 EXPORT_SYMBOL(cfg80211_unregister_wdev);
 842
 843 static const struct device_type wiphy_type = {
 844         .name   = "wlan",
 845 };
 846
 847 void cfg80211_update_iface_num(struct cfg80211_registered_device *rdev,
 848                                enum nl80211_iftype iftype, int num)
 849 {
 850         ASSERT_RTNL();
 851
 852         rdev->num_running_ifaces += num;
 853         if (iftype == NL80211_IFTYPE_MONITOR)
 854                 rdev->num_running_monitor_ifaces += num;
 855 }
 856
 857 void __cfg80211_leave(struct cfg80211_registered_device *rdev,
 858                       struct wireless_dev *wdev)
 859 {
 860         struct net_device *dev = wdev->netdev;
 861
 862         ASSERT_RTNL();
 863         ASSERT_WDEV_LOCK(wdev);
 864
 865         switch (wdev->iftype) {
 866         case NL80211_IFTYPE_ADHOC:
 867                 __cfg80211_leave_ibss(rdev, dev, true);
 868                 break;
 869         case NL80211_IFTYPE_P2P_CLIENT:
 870         case NL80211_IFTYPE_STATION:
 871                 if (rdev->sched_scan_req && dev == rdev->sched_scan_req->dev)
 872                         __cfg80211_stop_sched_scan(rdev, false);
 873
 874 #ifdef CONFIG_CFG80211_WEXT
 875                 kfree(wdev->wext.ie);
 876                 wdev->wext.ie = NULL;
 877                 wdev->wext.ie_len = 0;
 878                 wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
 879 #endif
 880                 cfg80211_disconnect(rdev, dev,
 881                                     WLAN_REASON_DEAUTH_LEAVING, true);
 882                 break;
 883         case NL80211_IFTYPE_MESH_POINT:
 884                 __cfg80211_leave_mesh(rdev, dev);
 885                 break;
 886         case NL80211_IFTYPE_AP:
 887         case NL80211_IFTYPE_P2P_GO:
 888                 __cfg80211_stop_ap(rdev, dev, true);
 889                 break;
 890         case NL80211_IFTYPE_OCB:
 891                 __cfg80211_leave_ocb(rdev, dev);
 892                 break;
 893         case NL80211_IFTYPE_WDS:
 894                 /* must be handled by mac80211/driver, has no APIs */
 895                 break;
 896         case NL80211_IFTYPE_P2P_DEVICE:
 897                 /* cannot happen, has no netdev */
 898                 break;
 899         case NL80211_IFTYPE_AP_VLAN:
 900         case NL80211_IFTYPE_MONITOR:
 901                 /* nothing to do */
 902                 break;
 903         case NL80211_IFTYPE_UNSPECIFIED:
 904         case NUM_NL80211_IFTYPES:
 905                 /* invalid */
 906                 break;
 907         }
 908 }
 909
 910 void cfg80211_leave(struct cfg80211_registered_device *rdev,
 911                     struct wireless_dev *wdev)
 912 {
 913         wdev_lock(wdev);
 914         __cfg80211_leave(rdev, wdev);
 915         wdev_unlock(wdev);
 916 }
 917
 918 void cfg80211_stop_iface(struct wiphy *wiphy, struct wireless_dev *wdev,
 919                          gfp_t gfp)
 920 {
 921         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 922         struct cfg80211_event *ev;
 923         unsigned long flags;
 924
 925         trace_cfg80211_stop_iface(wiphy, wdev);
 926
 927         ev = kzalloc(sizeof(*ev), gfp);
 928         if (!ev)
 929                 return;
 930
 931         ev->type = EVENT_STOPPED;
 932
 933         spin_lock_irqsave(&wdev->event_lock, flags);
 934         list_add_tail(&ev->list, &wdev->event_list);
 935         spin_unlock_irqrestore(&wdev->event_lock, flags);
 936         queue_work(cfg80211_wq, &rdev->event_work);
 937 }
 938 EXPORT_SYMBOL(cfg80211_stop_iface);
 939
 940 static int cfg80211_netdev_notifier_call(struct notifier_block *nb,
 941                                          unsigned long state, void *ptr)
 942 {
 943         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 944         struct wireless_dev *wdev = dev->ieee80211_ptr;
 945         struct cfg80211_registered_device *rdev;
 946
 947         if (!wdev)
 948                 return NOTIFY_DONE;
 949
 950         rdev = wiphy_to_rdev(wdev->wiphy);
 951
 952         WARN_ON(wdev->iftype == NL80211_IFTYPE_UNSPECIFIED);
 953
 954         switch (state) {
 955         case NETDEV_POST_INIT:
 956                 SET_NETDEV_DEVTYPE(dev, &wiphy_type);
 957                 break;
 958         case NETDEV_REGISTER:
 959                 /*
 960                  * NB: cannot take rdev->mtx here because this may be
 961                  * called within code protected by it when interfaces
 962                  * are added with nl80211.
 963                  */
 964                 mutex_init(&wdev->mtx);
 965                 INIT_LIST_HEAD(&wdev->event_list);
 966                 spin_lock_init(&wdev->event_lock);
 967                 INIT_LIST_HEAD(&wdev->mgmt_registrations);
 968                 spin_lock_init(&wdev->mgmt_registrations_lock);
 969
 970                 wdev->identifier = ++rdev->wdev_id;
 971                 list_add_rcu(&wdev->list, &rdev->wdev_list);
 972                 rdev->devlist_generation++;
 973                 /* can only change netns with wiphy */
 974                 dev->features |= NETIF_F_NETNS_LOCAL;
 975
 976                 if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
 977                                       "phy80211")) {
 978                         pr_err("failed to add phy80211 symlink to netdev!\n");
 979                 }
 980                 wdev->netdev = dev;
 981 #ifdef CONFIG_CFG80211_WEXT
 982                 wdev->wext.default_key = -1;
 983                 wdev->wext.default_mgmt_key = -1;
 984                 wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
 985 #endif
 986
 987                 if (wdev->wiphy->flags & WIPHY_FLAG_PS_ON_BY_DEFAULT)
 988                         wdev->ps = true;
 989                 else
 990                         wdev->ps = false;
 991                 /* allow mac80211 to determine the timeout */
 992                 wdev->ps_timeout = -1;
 993
 994                 if ((wdev->iftype == NL80211_IFTYPE_STATION ||
 995                      wdev->iftype == NL80211_IFTYPE_P2P_CLIENT ||
 996                      wdev->iftype == NL80211_IFTYPE_ADHOC) && !wdev->use_4addr)
 997                         dev->priv_flags |= IFF_DONT_BRIDGE;
 998                 break;
 999         case NETDEV_GOING_DOWN:
1000                 cfg80211_leave(rdev, wdev);
1001                 break;
1002         case NETDEV_DOWN:
1003                 cfg80211_update_iface_num(rdev, wdev->iftype, -1);
1004                 if (rdev->scan_req && rdev->scan_req->wdev == wdev) {
1005                         if (WARN_ON(!rdev->scan_req->notified))
1006                                 rdev->scan_req->aborted = true;
1007                         ___cfg80211_scan_done(rdev, false);
1008                 }
1009
1010                 if (WARN_ON(rdev->sched_scan_req &&
1011                             rdev->sched_scan_req->dev == wdev->netdev)) {
1012                         __cfg80211_stop_sched_scan(rdev, false);
1013                 }
1014
1015                 rdev->opencount--;
1016                 wake_up(&rdev->dev_wait);
1017                 break;
1018         case NETDEV_UP:
1019                 cfg80211_update_iface_num(rdev, wdev->iftype, 1);
1020                 wdev_lock(wdev);
1021                 switch (wdev->iftype) {
1022 #ifdef CONFIG_CFG80211_WEXT
1023                 case NL80211_IFTYPE_ADHOC:
1024                         cfg80211_ibss_wext_join(rdev, wdev);
1025                         break;
1026                 case NL80211_IFTYPE_STATION:
1027                         cfg80211_mgd_wext_connect(rdev, wdev);
1028                         break;
1029 #endif
1030 #ifdef CONFIG_MAC80211_MESH
1031                 case NL80211_IFTYPE_MESH_POINT:
1032                         {
1033                                 /* backward compat code... */
1034                                 struct mesh_setup setup;
1035                                 memcpy(&setup, &default_mesh_setup,
1036                                                 sizeof(setup));
1037                                  /* back compat only needed for mesh_id */
1038                                 setup.mesh_id = wdev->ssid;
1039                                 setup.mesh_id_len = wdev->mesh_id_up_len;
1040                                 if (wdev->mesh_id_up_len)
1041                                         __cfg80211_join_mesh(rdev, dev,
1042                                                         &setup,
1043                                                         &default_mesh_config);
1044                                 break;
1045                         }
1046 #endif
1047                 default:
1048                         break;
1049                 }
1050                 wdev_unlock(wdev);
1051                 rdev->opencount++;
1052
1053                 /*
1054                  * Configure power management to the driver here so that its
1055                  * correctly set also after interface type changes etc.
1056                  */
1057                 if ((wdev->iftype == NL80211_IFTYPE_STATION ||
1058                      wdev->iftype == NL80211_IFTYPE_P2P_CLIENT) &&
1059                     rdev->ops->set_power_mgmt)
1060                         if (rdev_set_power_mgmt(rdev, dev, wdev->ps,
1061                                                 wdev->ps_timeout)) {
1062                                 /* assume this means it's off */
1063                                 wdev->ps = false;
1064                         }
1065                 break;
1066         case NETDEV_UNREGISTER:
1067                 /*
1068                  * It is possible to get NETDEV_UNREGISTER
1069                  * multiple times. To detect that, check
1070                  * that the interface is still on the list
1071                  * of registered interfaces, and only then
1072                  * remove and clean it up.
1073                  */
1074                 if (!list_empty(&wdev->list)) {
1075                         sysfs_remove_link(&dev->dev.kobj, "phy80211");
1076                         list_del_rcu(&wdev->list);
1077                         rdev->devlist_generation++;
1078                         cfg80211_mlme_purge_registrations(wdev);
1079 #ifdef CONFIG_CFG80211_WEXT
1080                         kzfree(wdev->wext.keys);
1081 #endif
1082                 }
1083                 /*
1084                  * synchronise (so that we won't find this netdev
1085                  * from other code any more) and then clear the list
1086                  * head so that the above code can safely check for
1087                  * !list_empty() to avoid double-cleanup.
1088                  */
1089                 synchronize_rcu();
1090                 INIT_LIST_HEAD(&wdev->list);
1091                 /*
1092                  * Ensure that all events have been processed and
1093                  * freed.
1094                  */
1095                 cfg80211_process_wdev_events(wdev);
1096
1097                 if (WARN_ON(wdev->current_bss)) {
1098                         cfg80211_unhold_bss(wdev->current_bss);
1099                         cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
1100                         wdev->current_bss = NULL;
1101                 }
1102                 break;
1103         case NETDEV_PRE_UP:
1104                 if (!(wdev->wiphy->interface_modes & BIT(wdev->iftype)))
1105                         return notifier_from_errno(-EOPNOTSUPP);
1106                 if (rfkill_blocked(rdev->rfkill))
1107                         return notifier_from_errno(-ERFKILL);
1108                 break;
1109         default:
1110                 return NOTIFY_DONE;
1111         }
1112
1113         return NOTIFY_OK;
1114 }
1115
1116 static struct notifier_block cfg80211_netdev_notifier = {
1117         .notifier_call = cfg80211_netdev_notifier_call,
1118 };
1119
1120 static void __net_exit cfg80211_pernet_exit(struct net *net)
1121 {
1122         struct cfg80211_registered_device *rdev;
1123
1124         rtnl_lock();
1125         list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
1126                 if (net_eq(wiphy_net(&rdev->wiphy), net))
1127                         WARN_ON(cfg80211_switch_netns(rdev, &init_net));
1128         }
1129         rtnl_unlock();
1130 }
1131
1132 static struct pernet_operations cfg80211_pernet_ops = {
1133         .exit = cfg80211_pernet_exit,
1134 };
1135
1136 static int __init cfg80211_init(void)
1137 {
1138         int err;
1139
1140         err = register_pernet_device(&cfg80211_pernet_ops);
1141         if (err)
1142                 goto out_fail_pernet;
1143
1144         err = wiphy_sysfs_init();
1145         if (err)
1146                 goto out_fail_sysfs;
1147
1148         err = register_netdevice_notifier(&cfg80211_netdev_notifier);
1149         if (err)
1150                 goto out_fail_notifier;
1151
1152         err = nl80211_init();
1153         if (err)
1154                 goto out_fail_nl80211;
1155
1156         ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
1157
1158         err = regulatory_init();
1159         if (err)
1160                 goto out_fail_reg;
1161
1162         cfg80211_wq = create_singlethread_workqueue("cfg80211");
1163         if (!cfg80211_wq) {
1164                 err = -ENOMEM;
1165                 goto out_fail_wq;
1166         }
1167
1168         return 0;
1169
1170 out_fail_wq:
1171         regulatory_exit();
1172 out_fail_reg:
1173         debugfs_remove(ieee80211_debugfs_dir);
1174 out_fail_nl80211:
1175         unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1176 out_fail_notifier:
1177         wiphy_sysfs_exit();
1178 out_fail_sysfs:
1179         unregister_pernet_device(&cfg80211_pernet_ops);
1180 out_fail_pernet:
1181         return err;
1182 }
1183 subsys_initcall(cfg80211_init);
1184
1185 static void __exit cfg80211_exit(void)
1186 {
1187         debugfs_remove(ieee80211_debugfs_dir);
1188         nl80211_exit();
1189         unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1190         wiphy_sysfs_exit();
1191         regulatory_exit();
1192         unregister_pernet_device(&cfg80211_pernet_ops);
1193         destroy_workqueue(cfg80211_wq);
1194 }
1195 module_exit(cfg80211_exit);