SAFE public projects git trees. - safe/jmp/linux-2.6/blob - net/mac80211/scan.c

   1 /*
   2  * Scanning implementation
   3  *
   4  * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
   5  * Copyright 2004, Instant802 Networks, Inc.
   6  * Copyright 2005, Devicescape Software, Inc.
   7  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   8  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 /* TODO:
  16  * figure out how to avoid that the "current BSS" expires
  17  * use cfg80211's BSS handling
  18  */
  19
  20 #include <linux/wireless.h>
  21 #include <linux/if_arp.h>
  22 #include <linux/rtnetlink.h>
  23 #include <net/mac80211.h>
  24 #include <net/iw_handler.h>
  25
  26 #include "ieee80211_i.h"
  27 #include "mesh.h"
  28
  29 #define IEEE80211_PROBE_DELAY (HZ / 33)
  30 #define IEEE80211_CHANNEL_TIME (HZ / 33)
  31 #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 5)
  32
  33 void ieee80211_rx_bss_list_init(struct ieee80211_local *local)
  34 {
  35         spin_lock_init(&local->bss_lock);
  36         INIT_LIST_HEAD(&local->bss_list);
  37 }
  38
  39 void ieee80211_rx_bss_list_deinit(struct ieee80211_local *local)
  40 {
  41         struct ieee80211_bss *bss, *tmp;
  42
  43         list_for_each_entry_safe(bss, tmp, &local->bss_list, list)
  44                 ieee80211_rx_bss_put(local, bss);
  45 }
  46
  47 struct ieee80211_bss *
  48 ieee80211_rx_bss_get(struct ieee80211_local *local, u8 *bssid, int freq,
  49                      u8 *ssid, u8 ssid_len)
  50 {
  51         struct ieee80211_bss *bss;
  52
  53         spin_lock_bh(&local->bss_lock);
  54         bss = local->bss_hash[STA_HASH(bssid)];
  55         while (bss) {
  56                 if (!bss_mesh_cfg(bss) &&
  57                     !memcmp(bss->bssid, bssid, ETH_ALEN) &&
  58                     bss->freq == freq &&
  59                     bss->ssid_len == ssid_len &&
  60                     (ssid_len == 0 || !memcmp(bss->ssid, ssid, ssid_len))) {
  61                         atomic_inc(&bss->users);
  62                         break;
  63                 }
  64                 bss = bss->hnext;
  65         }
  66         spin_unlock_bh(&local->bss_lock);
  67         return bss;
  68 }
  69
  70 /* Caller must hold local->bss_lock */
  71 static void __ieee80211_rx_bss_hash_add(struct ieee80211_local *local,
  72                                         struct ieee80211_bss *bss)
  73 {
  74         u8 hash_idx;
  75
  76         if (bss_mesh_cfg(bss))
  77                 hash_idx = mesh_id_hash(bss_mesh_id(bss),
  78                                         bss_mesh_id_len(bss));
  79         else
  80                 hash_idx = STA_HASH(bss->bssid);
  81
  82         bss->hnext = local->bss_hash[hash_idx];
  83         local->bss_hash[hash_idx] = bss;
  84 }
  85
  86 /* Caller must hold local->bss_lock */
  87 static void __ieee80211_rx_bss_hash_del(struct ieee80211_local *local,
  88                                         struct ieee80211_bss *bss)
  89 {
  90         struct ieee80211_bss *b, *prev = NULL;
  91         b = local->bss_hash[STA_HASH(bss->bssid)];
  92         while (b) {
  93                 if (b == bss) {
  94                         if (!prev)
  95                                 local->bss_hash[STA_HASH(bss->bssid)] =
  96                                         bss->hnext;
  97                         else
  98                                 prev->hnext = bss->hnext;
  99                         break;
 100                 }
 101                 prev = b;
 102                 b = b->hnext;
 103         }
 104 }
 105
 106 static struct ieee80211_bss *
 107 ieee80211_rx_bss_add(struct ieee80211_local *local, u8 *bssid, int freq,
 108                      u8 *ssid, u8 ssid_len)
 109 {
 110         struct ieee80211_bss *bss;
 111
 112         bss = kzalloc(sizeof(*bss), GFP_ATOMIC);
 113         if (!bss)
 114                 return NULL;
 115         atomic_set(&bss->users, 2);
 116         memcpy(bss->bssid, bssid, ETH_ALEN);
 117         bss->freq = freq;
 118         if (ssid && ssid_len <= IEEE80211_MAX_SSID_LEN) {
 119                 memcpy(bss->ssid, ssid, ssid_len);
 120                 bss->ssid_len = ssid_len;
 121         }
 122
 123         spin_lock_bh(&local->bss_lock);
 124         /* TODO: order by RSSI? */
 125         list_add_tail(&bss->list, &local->bss_list);
 126         __ieee80211_rx_bss_hash_add(local, bss);
 127         spin_unlock_bh(&local->bss_lock);
 128         return bss;
 129 }
 130
 131 #ifdef CONFIG_MAC80211_MESH
 132 static struct ieee80211_bss *
 133 ieee80211_rx_mesh_bss_get(struct ieee80211_local *local, u8 *mesh_id, int mesh_id_len,
 134                           u8 *mesh_cfg, int freq)
 135 {
 136         struct ieee80211_bss *bss;
 137
 138         spin_lock_bh(&local->bss_lock);
 139         bss = local->bss_hash[mesh_id_hash(mesh_id, mesh_id_len)];
 140         while (bss) {
 141                 if (bss_mesh_cfg(bss) &&
 142                     !memcmp(bss_mesh_cfg(bss), mesh_cfg, MESH_CFG_CMP_LEN) &&
 143                     bss->freq == freq &&
 144                     mesh_id_len == bss->mesh_id_len &&
 145                     (mesh_id_len == 0 || !memcmp(bss->mesh_id, mesh_id,
 146                                                  mesh_id_len))) {
 147                         atomic_inc(&bss->users);
 148                         break;
 149                 }
 150                 bss = bss->hnext;
 151         }
 152         spin_unlock_bh(&local->bss_lock);
 153         return bss;
 154 }
 155
 156 static struct ieee80211_bss *
 157 ieee80211_rx_mesh_bss_add(struct ieee80211_local *local, u8 *mesh_id, int mesh_id_len,
 158                           u8 *mesh_cfg, int mesh_config_len, int freq)
 159 {
 160         struct ieee80211_bss *bss;
 161
 162         if (mesh_config_len != IEEE80211_MESH_CONFIG_LEN)
 163                 return NULL;
 164
 165         bss = kzalloc(sizeof(*bss), GFP_ATOMIC);
 166         if (!bss)
 167                 return NULL;
 168
 169         bss->mesh_cfg = kmalloc(MESH_CFG_CMP_LEN, GFP_ATOMIC);
 170         if (!bss->mesh_cfg) {
 171                 kfree(bss);
 172                 return NULL;
 173         }
 174
 175         if (mesh_id_len && mesh_id_len <= IEEE80211_MAX_MESH_ID_LEN) {
 176                 bss->mesh_id = kmalloc(mesh_id_len, GFP_ATOMIC);
 177                 if (!bss->mesh_id) {
 178                         kfree(bss->mesh_cfg);
 179                         kfree(bss);
 180                         return NULL;
 181                 }
 182                 memcpy(bss->mesh_id, mesh_id, mesh_id_len);
 183         }
 184
 185         atomic_set(&bss->users, 2);
 186         memcpy(bss->mesh_cfg, mesh_cfg, MESH_CFG_CMP_LEN);
 187         bss->mesh_id_len = mesh_id_len;
 188         bss->freq = freq;
 189         spin_lock_bh(&local->bss_lock);
 190         /* TODO: order by RSSI? */
 191         list_add_tail(&bss->list, &local->bss_list);
 192         __ieee80211_rx_bss_hash_add(local, bss);
 193         spin_unlock_bh(&local->bss_lock);
 194         return bss;
 195 }
 196 #endif
 197
 198 static void ieee80211_rx_bss_free(struct ieee80211_bss *bss)
 199 {
 200         kfree(bss->ies);
 201         kfree(bss_mesh_id(bss));
 202         kfree(bss_mesh_cfg(bss));
 203         kfree(bss);
 204 }
 205
 206 void ieee80211_rx_bss_put(struct ieee80211_local *local,
 207                           struct ieee80211_bss *bss)
 208 {
 209         local_bh_disable();
 210         if (!atomic_dec_and_lock(&bss->users, &local->bss_lock)) {
 211                 local_bh_enable();
 212                 return;
 213         }
 214
 215         __ieee80211_rx_bss_hash_del(local, bss);
 216         list_del(&bss->list);
 217         spin_unlock_bh(&local->bss_lock);
 218         ieee80211_rx_bss_free(bss);
 219 }
 220
 221 struct ieee80211_bss *
 222 ieee80211_bss_info_update(struct ieee80211_local *local,
 223                           struct ieee80211_rx_status *rx_status,
 224                           struct ieee80211_mgmt *mgmt,
 225                           size_t len,
 226                           struct ieee802_11_elems *elems,
 227                           struct ieee80211_channel *channel,
 228                           bool beacon)
 229 {
 230         struct ieee80211_bss *bss;
 231         int clen, freq = channel->center_freq;
 232         enum cfg80211_signal_type sigtype = CFG80211_SIGNAL_TYPE_NONE;
 233         s32 signal = 0;
 234
 235         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
 236                 sigtype = CFG80211_SIGNAL_TYPE_MBM;
 237                 signal = rx_status->signal * 100;
 238         } else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC) {
 239                 sigtype = CFG80211_SIGNAL_TYPE_UNSPEC;
 240                 signal = (rx_status->signal * 100) / local->hw.max_signal;
 241         }
 242
 243         cfg80211_put_bss(
 244                 cfg80211_inform_bss_frame(local->hw.wiphy, channel,
 245                                           mgmt, len, signal, sigtype,
 246                                           GFP_ATOMIC));
 247
 248 #ifdef CONFIG_MAC80211_MESH
 249         if (elems->mesh_config)
 250                 bss = ieee80211_rx_mesh_bss_get(local, elems->mesh_id,
 251                                 elems->mesh_id_len, elems->mesh_config, freq);
 252         else
 253 #endif
 254                 bss = ieee80211_rx_bss_get(local, mgmt->bssid, freq,
 255                                            elems->ssid, elems->ssid_len);
 256         if (!bss) {
 257 #ifdef CONFIG_MAC80211_MESH
 258                 if (elems->mesh_config)
 259                         bss = ieee80211_rx_mesh_bss_add(local, elems->mesh_id,
 260                                 elems->mesh_id_len, elems->mesh_config,
 261                                 elems->mesh_config_len, freq);
 262                 else
 263 #endif
 264                         bss = ieee80211_rx_bss_add(local, mgmt->bssid, freq,
 265                                                   elems->ssid, elems->ssid_len);
 266                 if (!bss)
 267                         return NULL;
 268         } else {
 269 #if 0
 270                 /* TODO: order by RSSI? */
 271                 spin_lock_bh(&local->bss_lock);
 272                 list_move_tail(&bss->list, &local->bss_list);
 273                 spin_unlock_bh(&local->bss_lock);
 274 #endif
 275         }
 276
 277         /* save the ERP value so that it is available at association time */
 278         if (elems->erp_info && elems->erp_info_len >= 1) {
 279                 bss->erp_value = elems->erp_info[0];
 280                 bss->has_erp_value = 1;
 281         }
 282
 283         bss->beacon_int = le16_to_cpu(mgmt->u.beacon.beacon_int);
 284         bss->capability = le16_to_cpu(mgmt->u.beacon.capab_info);
 285
 286         if (elems->tim) {
 287                 struct ieee80211_tim_ie *tim_ie =
 288                         (struct ieee80211_tim_ie *)elems->tim;
 289                 bss->dtim_period = tim_ie->dtim_period;
 290         }
 291
 292         /* set default value for buggy APs */
 293         if (!elems->tim || bss->dtim_period == 0)
 294                 bss->dtim_period = 1;
 295
 296         bss->supp_rates_len = 0;
 297         if (elems->supp_rates) {
 298                 clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len;
 299                 if (clen > elems->supp_rates_len)
 300                         clen = elems->supp_rates_len;
 301                 memcpy(&bss->supp_rates[bss->supp_rates_len], elems->supp_rates,
 302                        clen);
 303                 bss->supp_rates_len += clen;
 304         }
 305         if (elems->ext_supp_rates) {
 306                 clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len;
 307                 if (clen > elems->ext_supp_rates_len)
 308                         clen = elems->ext_supp_rates_len;
 309                 memcpy(&bss->supp_rates[bss->supp_rates_len],
 310                        elems->ext_supp_rates, clen);
 311                 bss->supp_rates_len += clen;
 312         }
 313
 314         bss->band = rx_status->band;
 315
 316         bss->timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
 317         bss->last_update = jiffies;
 318         bss->signal = rx_status->signal;
 319         bss->noise = rx_status->noise;
 320         bss->qual = rx_status->qual;
 321         bss->wmm_used = elems->wmm_param || elems->wmm_info;
 322
 323         if (!beacon)
 324                 bss->last_probe_resp = jiffies;
 325
 326         /*
 327          * For probe responses, or if we don't have any information yet,
 328          * use the IEs from the beacon.
 329          */
 330         if (!bss->ies || !beacon) {
 331                 if (bss->ies == NULL || bss->ies_len < elems->total_len) {
 332                         kfree(bss->ies);
 333                         bss->ies = kmalloc(elems->total_len, GFP_ATOMIC);
 334                 }
 335                 if (bss->ies) {
 336                         memcpy(bss->ies, elems->ie_start, elems->total_len);
 337                         bss->ies_len = elems->total_len;
 338                 } else
 339                         bss->ies_len = 0;
 340         }
 341
 342         return bss;
 343 }
 344
 345 void ieee80211_rx_bss_remove(struct ieee80211_sub_if_data *sdata, u8 *bssid,
 346                              int freq, u8 *ssid, u8 ssid_len)
 347 {
 348         struct ieee80211_bss *bss;
 349         struct ieee80211_local *local = sdata->local;
 350
 351         bss = ieee80211_rx_bss_get(local, bssid, freq, ssid, ssid_len);
 352         if (bss) {
 353                 atomic_dec(&bss->users);
 354                 ieee80211_rx_bss_put(local, bss);
 355         }
 356 }
 357
 358 ieee80211_rx_result
 359 ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
 360                   struct ieee80211_rx_status *rx_status)
 361 {
 362         struct ieee80211_mgmt *mgmt;
 363         struct ieee80211_bss *bss;
 364         u8 *elements;
 365         struct ieee80211_channel *channel;
 366         size_t baselen;
 367         int freq;
 368         __le16 fc;
 369         bool presp, beacon = false;
 370         struct ieee802_11_elems elems;
 371
 372         if (skb->len < 2)
 373                 return RX_DROP_UNUSABLE;
 374
 375         mgmt = (struct ieee80211_mgmt *) skb->data;
 376         fc = mgmt->frame_control;
 377
 378         if (ieee80211_is_ctl(fc))
 379                 return RX_CONTINUE;
 380
 381         if (skb->len < 24)
 382                 return RX_DROP_MONITOR;
 383
 384         presp = ieee80211_is_probe_resp(fc);
 385         if (presp) {
 386                 /* ignore ProbeResp to foreign address */
 387                 if (memcmp(mgmt->da, sdata->dev->dev_addr, ETH_ALEN))
 388                         return RX_DROP_MONITOR;
 389
 390                 presp = true;
 391                 elements = mgmt->u.probe_resp.variable;
 392                 baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable);
 393         } else {
 394                 beacon = ieee80211_is_beacon(fc);
 395                 baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable);
 396                 elements = mgmt->u.beacon.variable;
 397         }
 398
 399         if (!presp && !beacon)
 400                 return RX_CONTINUE;
 401
 402         if (baselen > skb->len)
 403                 return RX_DROP_MONITOR;
 404
 405         ieee802_11_parse_elems(elements, skb->len - baselen, &elems);
 406
 407         if (elems.ds_params && elems.ds_params_len == 1)
 408                 freq = ieee80211_channel_to_frequency(elems.ds_params[0]);
 409         else
 410                 freq = rx_status->freq;
 411
 412         channel = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
 413
 414         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 415                 return RX_DROP_MONITOR;
 416
 417         bss = ieee80211_bss_info_update(sdata->local, rx_status,
 418                                         mgmt, skb->len, &elems,
 419                                         channel, beacon);
 420         if (bss)
 421                 ieee80211_rx_bss_put(sdata->local, bss);
 422
 423         dev_kfree_skb(skb);
 424         return RX_QUEUED;
 425 }
 426
 427 void ieee80211_send_nullfunc(struct ieee80211_local *local,
 428                                     struct ieee80211_sub_if_data *sdata,
 429                                     int powersave)
 430 {
 431         struct sk_buff *skb;
 432         struct ieee80211_hdr *nullfunc;
 433         __le16 fc;
 434
 435         skb = dev_alloc_skb(local->hw.extra_tx_headroom + 24);
 436         if (!skb) {
 437                 printk(KERN_DEBUG "%s: failed to allocate buffer for nullfunc "
 438                        "frame\n", sdata->dev->name);
 439                 return;
 440         }
 441         skb_reserve(skb, local->hw.extra_tx_headroom);
 442
 443         nullfunc = (struct ieee80211_hdr *) skb_put(skb, 24);
 444         memset(nullfunc, 0, 24);
 445         fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_NULLFUNC |
 446                          IEEE80211_FCTL_TODS);
 447         if (powersave)
 448                 fc |= cpu_to_le16(IEEE80211_FCTL_PM);
 449         nullfunc->frame_control = fc;
 450         memcpy(nullfunc->addr1, sdata->u.sta.bssid, ETH_ALEN);
 451         memcpy(nullfunc->addr2, sdata->dev->dev_addr, ETH_ALEN);
 452         memcpy(nullfunc->addr3, sdata->u.sta.bssid, ETH_ALEN);
 453
 454         ieee80211_tx_skb(sdata, skb, 0);
 455 }
 456
 457 void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
 458 {
 459         struct ieee80211_local *local = hw_to_local(hw);
 460         struct ieee80211_sub_if_data *sdata;
 461
 462         if (WARN_ON(!local->hw_scanning && !local->sw_scanning))
 463                 return;
 464
 465         if (WARN_ON(!local->scan_req))
 466                 return;
 467
 468         if (local->scan_req != &local->int_scan_req)
 469                 cfg80211_scan_done(local->scan_req, aborted);
 470         local->scan_req = NULL;
 471
 472         local->last_scan_completed = jiffies;
 473
 474         if (local->hw_scanning) {
 475                 local->hw_scanning = false;
 476                 /*
 477                  * Somebody might have requested channel change during scan
 478                  * that we won't have acted upon, try now. ieee80211_hw_config
 479                  * will set the flag based on actual changes.
 480                  */
 481                 ieee80211_hw_config(local, 0);
 482                 goto done;
 483         }
 484
 485         local->sw_scanning = false;
 486         ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 487
 488         netif_tx_lock_bh(local->mdev);
 489         netif_addr_lock(local->mdev);
 490         local->filter_flags &= ~FIF_BCN_PRBRESP_PROMISC;
 491         local->ops->configure_filter(local_to_hw(local),
 492                                      FIF_BCN_PRBRESP_PROMISC,
 493                                      &local->filter_flags,
 494                                      local->mdev->mc_count,
 495                                      local->mdev->mc_list);
 496
 497         netif_addr_unlock(local->mdev);
 498         netif_tx_unlock_bh(local->mdev);
 499
 500         mutex_lock(&local->iflist_mtx);
 501         list_for_each_entry(sdata, &local->interfaces, list) {
 502                 if (!netif_running(sdata->dev))
 503                         continue;
 504
 505                 /* Tell AP we're back */
 506                 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
 507                         if (sdata->u.sta.flags & IEEE80211_STA_ASSOCIATED) {
 508                                 ieee80211_send_nullfunc(local, sdata, 0);
 509                                 netif_tx_wake_all_queues(sdata->dev);
 510                         }
 511                 } else
 512                         netif_tx_wake_all_queues(sdata->dev);
 513
 514                 /* re-enable beaconing */
 515                 if (sdata->vif.type == NL80211_IFTYPE_AP ||
 516                     sdata->vif.type == NL80211_IFTYPE_ADHOC ||
 517                     sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
 518                         ieee80211_if_config(sdata,
 519                                             IEEE80211_IFCC_BEACON_ENABLED);
 520         }
 521         mutex_unlock(&local->iflist_mtx);
 522
 523  done:
 524         ieee80211_mlme_notify_scan_completed(local);
 525         ieee80211_mesh_notify_scan_completed(local);
 526 }
 527 EXPORT_SYMBOL(ieee80211_scan_completed);
 528
 529 void ieee80211_scan_work(struct work_struct *work)
 530 {
 531         struct ieee80211_local *local =
 532                 container_of(work, struct ieee80211_local, scan_work.work);
 533         struct ieee80211_sub_if_data *sdata = local->scan_sdata;
 534         struct ieee80211_channel *chan;
 535         int skip, i;
 536         unsigned long next_delay = 0;
 537
 538         /*
 539          * Avoid re-scheduling when the sdata is going away.
 540          */
 541         if (!netif_running(sdata->dev))
 542                 return;
 543
 544         switch (local->scan_state) {
 545         case SCAN_SET_CHANNEL:
 546                 /* if no more bands/channels left, complete scan */
 547                 if (local->scan_channel_idx >= local->scan_req->n_channels) {
 548                         ieee80211_scan_completed(local_to_hw(local), false);
 549                         return;
 550                 }
 551                 skip = 0;
 552                 chan = local->scan_req->channels[local->scan_channel_idx];
 553
 554                 if (chan->flags & IEEE80211_CHAN_DISABLED ||
 555                     (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
 556                      chan->flags & IEEE80211_CHAN_NO_IBSS))
 557                         skip = 1;
 558
 559                 if (!skip) {
 560                         local->scan_channel = chan;
 561                         if (ieee80211_hw_config(local,
 562                                                 IEEE80211_CONF_CHANGE_CHANNEL))
 563                                 skip = 1;
 564                 }
 565
 566                 /* advance state machine to next channel/band */
 567                 local->scan_channel_idx++;
 568
 569                 if (skip)
 570                         break;
 571
 572                 next_delay = IEEE80211_PROBE_DELAY +
 573                              usecs_to_jiffies(local->hw.channel_change_time);
 574                 local->scan_state = SCAN_SEND_PROBE;
 575                 break;
 576         case SCAN_SEND_PROBE:
 577                 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
 578                 local->scan_state = SCAN_SET_CHANNEL;
 579
 580                 if (local->scan_channel->flags & IEEE80211_CHAN_PASSIVE_SCAN ||
 581                     !local->scan_req->n_ssids)
 582                         break;
 583                 for (i = 0; i < local->scan_req->n_ssids; i++)
 584                         ieee80211_send_probe_req(
 585                                 sdata, NULL,
 586                                 local->scan_req->ssids[i].ssid,
 587                                 local->scan_req->ssids[i].ssid_len);
 588                 next_delay = IEEE80211_CHANNEL_TIME;
 589                 break;
 590         }
 591
 592         queue_delayed_work(local->hw.workqueue, &local->scan_work,
 593                            next_delay);
 594 }
 595
 596
 597 int ieee80211_start_scan(struct ieee80211_sub_if_data *scan_sdata,
 598                          struct cfg80211_scan_request *req)
 599 {
 600         struct ieee80211_local *local = scan_sdata->local;
 601         struct ieee80211_sub_if_data *sdata;
 602
 603         if (!req)
 604                 return -EINVAL;
 605
 606         if (local->scan_req && local->scan_req != req)
 607                 return -EBUSY;
 608
 609         local->scan_req = req;
 610
 611         /* MLME-SCAN.request (page 118)  page 144 (11.1.3.1)
 612          * BSSType: INFRASTRUCTURE, INDEPENDENT, ANY_BSS
 613          * BSSID: MACAddress
 614          * SSID
 615          * ScanType: ACTIVE, PASSIVE
 616          * ProbeDelay: delay (in microseconds) to be used prior to transmitting
 617          *    a Probe frame during active scanning
 618          * ChannelList
 619          * MinChannelTime (>= ProbeDelay), in TU
 620          * MaxChannelTime: (>= MinChannelTime), in TU
 621          */
 622
 623          /* MLME-SCAN.confirm
 624           * BSSDescriptionSet
 625           * ResultCode: SUCCESS, INVALID_PARAMETERS
 626          */
 627
 628         if (local->sw_scanning || local->hw_scanning) {
 629                 if (local->scan_sdata == scan_sdata)
 630                         return 0;
 631                 return -EBUSY;
 632         }
 633
 634         if (local->ops->hw_scan) {
 635                 int rc;
 636
 637                 local->hw_scanning = true;
 638                 rc = local->ops->hw_scan(local_to_hw(local), req);
 639                 if (rc) {
 640                         local->hw_scanning = false;
 641                         return rc;
 642                 }
 643                 local->scan_sdata = scan_sdata;
 644                 return 0;
 645         }
 646
 647         local->sw_scanning = true;
 648
 649         mutex_lock(&local->iflist_mtx);
 650         list_for_each_entry(sdata, &local->interfaces, list) {
 651                 if (!netif_running(sdata->dev))
 652                         continue;
 653
 654                 /* disable beaconing */
 655                 if (sdata->vif.type == NL80211_IFTYPE_AP ||
 656                     sdata->vif.type == NL80211_IFTYPE_ADHOC ||
 657                     sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
 658                         ieee80211_if_config(sdata,
 659                                             IEEE80211_IFCC_BEACON_ENABLED);
 660
 661                 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
 662                         if (sdata->u.sta.flags & IEEE80211_STA_ASSOCIATED) {
 663                                 netif_tx_stop_all_queues(sdata->dev);
 664                                 ieee80211_send_nullfunc(local, sdata, 1);
 665                         }
 666                 } else
 667                         netif_tx_stop_all_queues(sdata->dev);
 668         }
 669         mutex_unlock(&local->iflist_mtx);
 670
 671         local->scan_state = SCAN_SET_CHANNEL;
 672         local->scan_channel_idx = 0;
 673         local->scan_sdata = scan_sdata;
 674         local->scan_req = req;
 675
 676         netif_addr_lock_bh(local->mdev);
 677         local->filter_flags |= FIF_BCN_PRBRESP_PROMISC;
 678         local->ops->configure_filter(local_to_hw(local),
 679                                      FIF_BCN_PRBRESP_PROMISC,
 680                                      &local->filter_flags,
 681                                      local->mdev->mc_count,
 682                                      local->mdev->mc_list);
 683         netif_addr_unlock_bh(local->mdev);
 684
 685         /* TODO: start scan as soon as all nullfunc frames are ACKed */
 686         queue_delayed_work(local->hw.workqueue, &local->scan_work,
 687                            IEEE80211_CHANNEL_TIME);
 688
 689         return 0;
 690 }
 691
 692
 693 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
 694                            struct cfg80211_scan_request *req)
 695 {
 696         struct ieee80211_local *local = sdata->local;
 697         struct ieee80211_if_sta *ifsta;
 698
 699         if (!req)
 700                 return -EINVAL;
 701
 702         if (local->scan_req && local->scan_req != req)
 703                 return -EBUSY;
 704
 705         local->scan_req = req;
 706
 707         if (sdata->vif.type != NL80211_IFTYPE_STATION)
 708                 return ieee80211_start_scan(sdata, req);
 709
 710         /*
 711          * STA has a state machine that might need to defer scanning
 712          * while it's trying to associate/authenticate, therefore we
 713          * queue it up to the state machine in that case.
 714          */
 715
 716         if (local->sw_scanning || local->hw_scanning) {
 717                 if (local->scan_sdata == sdata)
 718                         return 0;
 719                 return -EBUSY;
 720         }
 721
 722         ifsta = &sdata->u.sta;
 723         set_bit(IEEE80211_STA_REQ_SCAN, &ifsta->request);
 724         queue_work(local->hw.workqueue, &ifsta->work);
 725
 726         return 0;
 727 }