net/mac80211/util.c

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   5  * Copyright 2007       Johannes Berg <johannes@sipsolutions.net>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  * utilities for mac80211
  12  */
  13
  14 #include <net/mac80211.h>
  15 #include <linux/netdevice.h>
  16 #include <linux/types.h>
  17 #include <linux/slab.h>
  18 #include <linux/skbuff.h>
  19 #include <linux/etherdevice.h>
  20 #include <linux/if_arp.h>
  21 #include <linux/wireless.h>
  22 #include <linux/bitmap.h>
  23 #include <linux/crc32.h>
  24 #include <net/net_namespace.h>
  25 #include <net/cfg80211.h>
  26 #include <net/rtnetlink.h>
  27
  28 #include "ieee80211_i.h"
  29 #include "driver-ops.h"
  30 #include "rate.h"
  31 #include "mesh.h"
  32 #include "wme.h"
  33 #include "led.h"
  34 #include "wep.h"
  35
  36 /* privid for wiphys to determine whether they belong to us or not */
  37 void *mac80211_wiphy_privid = &mac80211_wiphy_privid;
  38
  39 struct ieee80211_hw *wiphy_to_ieee80211_hw(struct wiphy *wiphy)
  40 {
  41         struct ieee80211_local *local;
  42         BUG_ON(!wiphy);
  43
  44         local = wiphy_priv(wiphy);
  45         return &local->hw;
  46 }
  47 EXPORT_SYMBOL(wiphy_to_ieee80211_hw);
  48
  49 u8 *ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len,
  50                         enum nl80211_iftype type)
  51 {
  52         __le16 fc = hdr->frame_control;
  53
  54          /* drop ACK/CTS frames and incorrect hdr len (ctrl) */
  55         if (len < 16)
  56                 return NULL;
  57
  58         if (ieee80211_is_data(fc)) {
  59                 if (len < 24) /* drop incorrect hdr len (data) */
  60                         return NULL;
  61
  62                 if (ieee80211_has_a4(fc))
  63                         return NULL;
  64                 if (ieee80211_has_tods(fc))
  65                         return hdr->addr1;
  66                 if (ieee80211_has_fromds(fc))
  67                         return hdr->addr2;
  68
  69                 return hdr->addr3;
  70         }
  71
  72         if (ieee80211_is_mgmt(fc)) {
  73                 if (len < 24) /* drop incorrect hdr len (mgmt) */
  74                         return NULL;
  75                 return hdr->addr3;
  76         }
  77
  78         if (ieee80211_is_ctl(fc)) {
  79                 if(ieee80211_is_pspoll(fc))
  80                         return hdr->addr1;
  81
  82                 if (ieee80211_is_back_req(fc)) {
  83                         switch (type) {
  84                         case NL80211_IFTYPE_STATION:
  85                                 return hdr->addr2;
  86                         case NL80211_IFTYPE_AP:
  87                         case NL80211_IFTYPE_AP_VLAN:
  88                                 return hdr->addr1;
  89                         default:
  90                                 break; /* fall through to the return */
  91                         }
  92                 }
  93         }
  94
  95         return NULL;
  96 }
  97
  98 void ieee80211_tx_set_protected(struct ieee80211_tx_data *tx)
  99 {
 100         struct sk_buff *skb = tx->skb;
 101         struct ieee80211_hdr *hdr;
 102
 103         do {
 104                 hdr = (struct ieee80211_hdr *) skb->data;
 105                 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 106         } while ((skb = skb->next));
 107 }
 108
 109 int ieee80211_frame_duration(struct ieee80211_local *local, size_t len,
 110                              int rate, int erp, int short_preamble)
 111 {
 112         int dur;
 113
 114         /* calculate duration (in microseconds, rounded up to next higher
 115          * integer if it includes a fractional microsecond) to send frame of
 116          * len bytes (does not include FCS) at the given rate. Duration will
 117          * also include SIFS.
 118          *
 119          * rate is in 100 kbps, so divident is multiplied by 10 in the
 120          * DIV_ROUND_UP() operations.
 121          */
 122
 123         if (local->hw.conf.channel->band == IEEE80211_BAND_5GHZ || erp) {
 124                 /*
 125                  * OFDM:
 126                  *
 127                  * N_DBPS = DATARATE x 4
 128                  * N_SYM = Ceiling((16+8xLENGTH+6) / N_DBPS)
 129                  *      (16 = SIGNAL time, 6 = tail bits)
 130                  * TXTIME = T_PREAMBLE + T_SIGNAL + T_SYM x N_SYM + Signal Ext
 131                  *
 132                  * T_SYM = 4 usec
 133                  * 802.11a - 17.5.2: aSIFSTime = 16 usec
 134                  * 802.11g - 19.8.4: aSIFSTime = 10 usec +
 135                  *      signal ext = 6 usec
 136                  */
 137                 dur = 16; /* SIFS + signal ext */
 138                 dur += 16; /* 17.3.2.3: T_PREAMBLE = 16 usec */
 139                 dur += 4; /* 17.3.2.3: T_SIGNAL = 4 usec */
 140                 dur += 4 * DIV_ROUND_UP((16 + 8 * (len + 4) + 6) * 10,
 141                                         4 * rate); /* T_SYM x N_SYM */
 142         } else {
 143                 /*
 144                  * 802.11b or 802.11g with 802.11b compatibility:
 145                  * 18.3.4: TXTIME = PreambleLength + PLCPHeaderTime +
 146                  * Ceiling(((LENGTH+PBCC)x8)/DATARATE). PBCC=0.
 147                  *
 148                  * 802.11 (DS): 15.3.3, 802.11b: 18.3.4
 149                  * aSIFSTime = 10 usec
 150                  * aPreambleLength = 144 usec or 72 usec with short preamble
 151                  * aPLCPHeaderLength = 48 usec or 24 usec with short preamble
 152                  */
 153                 dur = 10; /* aSIFSTime = 10 usec */
 154                 dur += short_preamble ? (72 + 24) : (144 + 48);
 155
 156                 dur += DIV_ROUND_UP(8 * (len + 4) * 10, rate);
 157         }
 158
 159         return dur;
 160 }
 161
 162 /* Exported duration function for driver use */
 163 __le16 ieee80211_generic_frame_duration(struct ieee80211_hw *hw,
 164                                         struct ieee80211_vif *vif,
 165                                         size_t frame_len,
 166                                         struct ieee80211_rate *rate)
 167 {
 168         struct ieee80211_local *local = hw_to_local(hw);
 169         struct ieee80211_sub_if_data *sdata;
 170         u16 dur;
 171         int erp;
 172         bool short_preamble = false;
 173
 174         erp = 0;
 175         if (vif) {
 176                 sdata = vif_to_sdata(vif);
 177                 short_preamble = sdata->vif.bss_conf.use_short_preamble;
 178                 if (sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
 179                         erp = rate->flags & IEEE80211_RATE_ERP_G;
 180         }
 181
 182         dur = ieee80211_frame_duration(local, frame_len, rate->bitrate, erp,
 183                                        short_preamble);
 184
 185         return cpu_to_le16(dur);
 186 }
 187 EXPORT_SYMBOL(ieee80211_generic_frame_duration);
 188
 189 __le16 ieee80211_rts_duration(struct ieee80211_hw *hw,
 190                               struct ieee80211_vif *vif, size_t frame_len,
 191                               const struct ieee80211_tx_info *frame_txctl)
 192 {
 193         struct ieee80211_local *local = hw_to_local(hw);
 194         struct ieee80211_rate *rate;
 195         struct ieee80211_sub_if_data *sdata;
 196         bool short_preamble;
 197         int erp;
 198         u16 dur;
 199         struct ieee80211_supported_band *sband;
 200
 201         sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
 202
 203         short_preamble = false;
 204
 205         rate = &sband->bitrates[frame_txctl->control.rts_cts_rate_idx];
 206
 207         erp = 0;
 208         if (vif) {
 209                 sdata = vif_to_sdata(vif);
 210                 short_preamble = sdata->vif.bss_conf.use_short_preamble;
 211                 if (sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
 212                         erp = rate->flags & IEEE80211_RATE_ERP_G;
 213         }
 214
 215         /* CTS duration */
 216         dur = ieee80211_frame_duration(local, 10, rate->bitrate,
 217                                        erp, short_preamble);
 218         /* Data frame duration */
 219         dur += ieee80211_frame_duration(local, frame_len, rate->bitrate,
 220                                         erp, short_preamble);
 221         /* ACK duration */
 222         dur += ieee80211_frame_duration(local, 10, rate->bitrate,
 223                                         erp, short_preamble);
 224
 225         return cpu_to_le16(dur);
 226 }
 227 EXPORT_SYMBOL(ieee80211_rts_duration);
 228
 229 __le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw,
 230                                     struct ieee80211_vif *vif,
 231                                     size_t frame_len,
 232                                     const struct ieee80211_tx_info *frame_txctl)
 233 {
 234         struct ieee80211_local *local = hw_to_local(hw);
 235         struct ieee80211_rate *rate;
 236         struct ieee80211_sub_if_data *sdata;
 237         bool short_preamble;
 238         int erp;
 239         u16 dur;
 240         struct ieee80211_supported_band *sband;
 241
 242         sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
 243
 244         short_preamble = false;
 245
 246         rate = &sband->bitrates[frame_txctl->control.rts_cts_rate_idx];
 247         erp = 0;
 248         if (vif) {
 249                 sdata = vif_to_sdata(vif);
 250                 short_preamble = sdata->vif.bss_conf.use_short_preamble;
 251                 if (sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
 252                         erp = rate->flags & IEEE80211_RATE_ERP_G;
 253         }
 254
 255         /* Data frame duration */
 256         dur = ieee80211_frame_duration(local, frame_len, rate->bitrate,
 257                                        erp, short_preamble);
 258         if (!(frame_txctl->flags & IEEE80211_TX_CTL_NO_ACK)) {
 259                 /* ACK duration */
 260                 dur += ieee80211_frame_duration(local, 10, rate->bitrate,
 261                                                 erp, short_preamble);
 262         }
 263
 264         return cpu_to_le16(dur);
 265 }
 266 EXPORT_SYMBOL(ieee80211_ctstoself_duration);
 267
 268 static void __ieee80211_wake_queue(struct ieee80211_hw *hw, int queue,
 269                                    enum queue_stop_reason reason)
 270 {
 271         struct ieee80211_local *local = hw_to_local(hw);
 272
 273         if (WARN_ON(queue >= hw->queues))
 274                 return;
 275
 276         __clear_bit(reason, &local->queue_stop_reasons[queue]);
 277
 278         if (local->queue_stop_reasons[queue] != 0)
 279                 /* someone still has this queue stopped */
 280                 return;
 281
 282         if (!skb_queue_empty(&local->pending[queue]))
 283                 tasklet_schedule(&local->tx_pending_tasklet);
 284 }
 285
 286 void ieee80211_wake_queue_by_reason(struct ieee80211_hw *hw, int queue,
 287                                     enum queue_stop_reason reason)
 288 {
 289         struct ieee80211_local *local = hw_to_local(hw);
 290         unsigned long flags;
 291
 292         spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
 293         __ieee80211_wake_queue(hw, queue, reason);
 294         spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
 295 }
 296
 297 void ieee80211_wake_queue(struct ieee80211_hw *hw, int queue)
 298 {
 299         ieee80211_wake_queue_by_reason(hw, queue,
 300                                        IEEE80211_QUEUE_STOP_REASON_DRIVER);
 301 }
 302 EXPORT_SYMBOL(ieee80211_wake_queue);
 303
 304 static void __ieee80211_stop_queue(struct ieee80211_hw *hw, int queue,
 305                                    enum queue_stop_reason reason)
 306 {
 307         struct ieee80211_local *local = hw_to_local(hw);
 308
 309         if (WARN_ON(queue >= hw->queues))
 310                 return;
 311
 312         __set_bit(reason, &local->queue_stop_reasons[queue]);
 313 }
 314
 315 void ieee80211_stop_queue_by_reason(struct ieee80211_hw *hw, int queue,
 316                                     enum queue_stop_reason reason)
 317 {
 318         struct ieee80211_local *local = hw_to_local(hw);
 319         unsigned long flags;
 320
 321         spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
 322         __ieee80211_stop_queue(hw, queue, reason);
 323         spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
 324 }
 325
 326 void ieee80211_stop_queue(struct ieee80211_hw *hw, int queue)
 327 {
 328         ieee80211_stop_queue_by_reason(hw, queue,
 329                                        IEEE80211_QUEUE_STOP_REASON_DRIVER);
 330 }
 331 EXPORT_SYMBOL(ieee80211_stop_queue);
 332
 333 void ieee80211_add_pending_skb(struct ieee80211_local *local,
 334                                struct sk_buff *skb)
 335 {
 336         struct ieee80211_hw *hw = &local->hw;
 337         unsigned long flags;
 338         int queue = skb_get_queue_mapping(skb);
 339         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 340
 341         if (WARN_ON(!info->control.vif)) {
 342                 kfree_skb(skb);
 343                 return;
 344         }
 345
 346         spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
 347         __ieee80211_stop_queue(hw, queue, IEEE80211_QUEUE_STOP_REASON_SKB_ADD);
 348         __skb_queue_tail(&local->pending[queue], skb);
 349         __ieee80211_wake_queue(hw, queue, IEEE80211_QUEUE_STOP_REASON_SKB_ADD);
 350         spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
 351 }
 352
 353 int ieee80211_add_pending_skbs(struct ieee80211_local *local,
 354                                struct sk_buff_head *skbs)
 355 {
 356         struct ieee80211_hw *hw = &local->hw;
 357         struct sk_buff *skb;
 358         unsigned long flags;
 359         int queue, ret = 0, i;
 360
 361         spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
 362         for (i = 0; i < hw->queues; i++)
 363                 __ieee80211_stop_queue(hw, i,
 364                         IEEE80211_QUEUE_STOP_REASON_SKB_ADD);
 365
 366         while ((skb = skb_dequeue(skbs))) {
 367                 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 368
 369                 if (WARN_ON(!info->control.vif)) {
 370                         kfree_skb(skb);
 371                         continue;
 372                 }
 373
 374                 ret++;
 375                 queue = skb_get_queue_mapping(skb);
 376                 __skb_queue_tail(&local->pending[queue], skb);
 377         }
 378
 379         for (i = 0; i < hw->queues; i++)
 380                 __ieee80211_wake_queue(hw, i,
 381                         IEEE80211_QUEUE_STOP_REASON_SKB_ADD);
 382         spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
 383
 384         return ret;
 385 }
 386
 387 void ieee80211_stop_queues_by_reason(struct ieee80211_hw *hw,
 388                                     enum queue_stop_reason reason)
 389 {
 390         struct ieee80211_local *local = hw_to_local(hw);
 391         unsigned long flags;
 392         int i;
 393
 394         spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
 395
 396         for (i = 0; i < hw->queues; i++)
 397                 __ieee80211_stop_queue(hw, i, reason);
 398
 399         spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
 400 }
 401
 402 void ieee80211_stop_queues(struct ieee80211_hw *hw)
 403 {
 404         ieee80211_stop_queues_by_reason(hw,
 405                                         IEEE80211_QUEUE_STOP_REASON_DRIVER);
 406 }
 407 EXPORT_SYMBOL(ieee80211_stop_queues);
 408
 409 int ieee80211_queue_stopped(struct ieee80211_hw *hw, int queue)
 410 {
 411         struct ieee80211_local *local = hw_to_local(hw);
 412         unsigned long flags;
 413         int ret;
 414
 415         if (WARN_ON(queue >= hw->queues))
 416                 return true;
 417
 418         spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
 419         ret = !!local->queue_stop_reasons[queue];
 420         spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
 421         return ret;
 422 }
 423 EXPORT_SYMBOL(ieee80211_queue_stopped);
 424
 425 void ieee80211_wake_queues_by_reason(struct ieee80211_hw *hw,
 426                                      enum queue_stop_reason reason)
 427 {
 428         struct ieee80211_local *local = hw_to_local(hw);
 429         unsigned long flags;
 430         int i;
 431
 432         spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
 433
 434         for (i = 0; i < hw->queues; i++)
 435                 __ieee80211_wake_queue(hw, i, reason);
 436
 437         spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
 438 }
 439
 440 void ieee80211_wake_queues(struct ieee80211_hw *hw)
 441 {
 442         ieee80211_wake_queues_by_reason(hw, IEEE80211_QUEUE_STOP_REASON_DRIVER);
 443 }
 444 EXPORT_SYMBOL(ieee80211_wake_queues);
 445
 446 void ieee80211_iterate_active_interfaces(
 447         struct ieee80211_hw *hw,
 448         void (*iterator)(void *data, u8 *mac,
 449                          struct ieee80211_vif *vif),
 450         void *data)
 451 {
 452         struct ieee80211_local *local = hw_to_local(hw);
 453         struct ieee80211_sub_if_data *sdata;
 454
 455         mutex_lock(&local->iflist_mtx);
 456
 457         list_for_each_entry(sdata, &local->interfaces, list) {
 458                 switch (sdata->vif.type) {
 459                 case __NL80211_IFTYPE_AFTER_LAST:
 460                 case NL80211_IFTYPE_UNSPECIFIED:
 461                 case NL80211_IFTYPE_MONITOR:
 462                 case NL80211_IFTYPE_AP_VLAN:
 463                         continue;
 464                 case NL80211_IFTYPE_AP:
 465                 case NL80211_IFTYPE_STATION:
 466                 case NL80211_IFTYPE_ADHOC:
 467                 case NL80211_IFTYPE_WDS:
 468                 case NL80211_IFTYPE_MESH_POINT:
 469                         break;
 470                 }
 471                 if (ieee80211_sdata_running(sdata))
 472                         iterator(data, sdata->vif.addr,
 473                                  &sdata->vif);
 474         }
 475
 476         mutex_unlock(&local->iflist_mtx);
 477 }
 478 EXPORT_SYMBOL_GPL(ieee80211_iterate_active_interfaces);
 479
 480 void ieee80211_iterate_active_interfaces_atomic(
 481         struct ieee80211_hw *hw,
 482         void (*iterator)(void *data, u8 *mac,
 483                          struct ieee80211_vif *vif),
 484         void *data)
 485 {
 486         struct ieee80211_local *local = hw_to_local(hw);
 487         struct ieee80211_sub_if_data *sdata;
 488
 489         rcu_read_lock();
 490
 491         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 492                 switch (sdata->vif.type) {
 493                 case __NL80211_IFTYPE_AFTER_LAST:
 494                 case NL80211_IFTYPE_UNSPECIFIED:
 495                 case NL80211_IFTYPE_MONITOR:
 496                 case NL80211_IFTYPE_AP_VLAN:
 497                         continue;
 498                 case NL80211_IFTYPE_AP:
 499                 case NL80211_IFTYPE_STATION:
 500                 case NL80211_IFTYPE_ADHOC:
 501                 case NL80211_IFTYPE_WDS:
 502                 case NL80211_IFTYPE_MESH_POINT:
 503                         break;
 504                 }
 505                 if (ieee80211_sdata_running(sdata))
 506                         iterator(data, sdata->vif.addr,
 507                                  &sdata->vif);
 508         }
 509
 510         rcu_read_unlock();
 511 }
 512 EXPORT_SYMBOL_GPL(ieee80211_iterate_active_interfaces_atomic);
 513
 514 /*
 515  * Nothing should have been stuffed into the workqueue during
 516  * the suspend->resume cycle. If this WARN is seen then there
 517  * is a bug with either the driver suspend or something in
 518  * mac80211 stuffing into the workqueue which we haven't yet
 519  * cleared during mac80211's suspend cycle.
 520  */
 521 static bool ieee80211_can_queue_work(struct ieee80211_local *local)
 522 {
 523         if (WARN(local->suspended && !local->resuming,
 524                  "queueing ieee80211 work while going to suspend\n"))
 525                 return false;
 526
 527         return true;
 528 }
 529
 530 void ieee80211_queue_work(struct ieee80211_hw *hw, struct work_struct *work)
 531 {
 532         struct ieee80211_local *local = hw_to_local(hw);
 533
 534         if (!ieee80211_can_queue_work(local))
 535                 return;
 536
 537         queue_work(local->workqueue, work);
 538 }
 539 EXPORT_SYMBOL(ieee80211_queue_work);
 540
 541 void ieee80211_queue_delayed_work(struct ieee80211_hw *hw,
 542                                   struct delayed_work *dwork,
 543                                   unsigned long delay)
 544 {
 545         struct ieee80211_local *local = hw_to_local(hw);
 546
 547         if (!ieee80211_can_queue_work(local))
 548                 return;
 549
 550         queue_delayed_work(local->workqueue, dwork, delay);
 551 }
 552 EXPORT_SYMBOL(ieee80211_queue_delayed_work);
 553
 554 void ieee802_11_parse_elems(u8 *start, size_t len,
 555                             struct ieee802_11_elems *elems)
 556 {
 557         ieee802_11_parse_elems_crc(start, len, elems, 0, 0);
 558 }
 559
 560 u32 ieee802_11_parse_elems_crc(u8 *start, size_t len,
 561                                struct ieee802_11_elems *elems,
 562                                u64 filter, u32 crc)
 563 {
 564         size_t left = len;
 565         u8 *pos = start;
 566         bool calc_crc = filter != 0;
 567
 568         memset(elems, 0, sizeof(*elems));
 569         elems->ie_start = start;
 570         elems->total_len = len;
 571
 572         while (left >= 2) {
 573                 u8 id, elen;
 574
 575                 id = *pos++;
 576                 elen = *pos++;
 577                 left -= 2;
 578
 579                 if (elen > left)
 580                         break;
 581
 582                 if (calc_crc && id < 64 && (filter & (1ULL << id)))
 583                         crc = crc32_be(crc, pos - 2, elen + 2);
 584
 585                 switch (id) {
 586                 case WLAN_EID_SSID:
 587                         elems->ssid = pos;
 588                         elems->ssid_len = elen;
 589                         break;
 590                 case WLAN_EID_SUPP_RATES:
 591                         elems->supp_rates = pos;
 592                         elems->supp_rates_len = elen;
 593                         break;
 594                 case WLAN_EID_FH_PARAMS:
 595                         elems->fh_params = pos;
 596                         elems->fh_params_len = elen;
 597                         break;
 598                 case WLAN_EID_DS_PARAMS:
 599                         elems->ds_params = pos;
 600                         elems->ds_params_len = elen;
 601                         break;
 602                 case WLAN_EID_CF_PARAMS:
 603                         elems->cf_params = pos;
 604                         elems->cf_params_len = elen;
 605                         break;
 606                 case WLAN_EID_TIM:
 607                         if (elen >= sizeof(struct ieee80211_tim_ie)) {
 608                                 elems->tim = (void *)pos;
 609                                 elems->tim_len = elen;
 610                         }
 611                         break;
 612                 case WLAN_EID_IBSS_PARAMS:
 613                         elems->ibss_params = pos;
 614                         elems->ibss_params_len = elen;
 615                         break;
 616                 case WLAN_EID_CHALLENGE:
 617                         elems->challenge = pos;
 618                         elems->challenge_len = elen;
 619                         break;
 620                 case WLAN_EID_VENDOR_SPECIFIC:
 621                         if (elen >= 4 && pos[0] == 0x00 && pos[1] == 0x50 &&
 622                             pos[2] == 0xf2) {
 623                                 /* Microsoft OUI (00:50:F2) */
 624
 625                                 if (calc_crc)
 626                                         crc = crc32_be(crc, pos - 2, elen + 2);
 627
 628                                 if (pos[3] == 1) {
 629                                         /* OUI Type 1 - WPA IE */
 630                                         elems->wpa = pos;
 631                                         elems->wpa_len = elen;
 632                                 } else if (elen >= 5 && pos[3] == 2) {
 633                                         /* OUI Type 2 - WMM IE */
 634                                         if (pos[4] == 0) {
 635                                                 elems->wmm_info = pos;
 636                                                 elems->wmm_info_len = elen;
 637                                         } else if (pos[4] == 1) {
 638                                                 elems->wmm_param = pos;
 639                                                 elems->wmm_param_len = elen;
 640                                         }
 641                                 }
 642                         }
 643                         break;
 644                 case WLAN_EID_RSN:
 645                         elems->rsn = pos;
 646                         elems->rsn_len = elen;
 647                         break;
 648                 case WLAN_EID_ERP_INFO:
 649                         elems->erp_info = pos;
 650                         elems->erp_info_len = elen;
 651                         break;
 652                 case WLAN_EID_EXT_SUPP_RATES:
 653                         elems->ext_supp_rates = pos;
 654                         elems->ext_supp_rates_len = elen;
 655                         break;
 656                 case WLAN_EID_HT_CAPABILITY:
 657                         if (elen >= sizeof(struct ieee80211_ht_cap))
 658                                 elems->ht_cap_elem = (void *)pos;
 659                         break;
 660                 case WLAN_EID_HT_INFORMATION:
 661                         if (elen >= sizeof(struct ieee80211_ht_info))
 662                                 elems->ht_info_elem = (void *)pos;
 663                         break;
 664                 case WLAN_EID_MESH_ID:
 665                         elems->mesh_id = pos;
 666                         elems->mesh_id_len = elen;
 667                         break;
 668                 case WLAN_EID_MESH_CONFIG:
 669                         if (elen >= sizeof(struct ieee80211_meshconf_ie))
 670                                 elems->mesh_config = (void *)pos;
 671                         break;
 672                 case WLAN_EID_PEER_LINK:
 673                         elems->peer_link = pos;
 674                         elems->peer_link_len = elen;
 675                         break;
 676                 case WLAN_EID_PREQ:
 677                         elems->preq = pos;
 678                         elems->preq_len = elen;
 679                         break;
 680                 case WLAN_EID_PREP:
 681                         elems->prep = pos;
 682                         elems->prep_len = elen;
 683                         break;
 684                 case WLAN_EID_PERR:
 685                         elems->perr = pos;
 686                         elems->perr_len = elen;
 687                         break;
 688                 case WLAN_EID_RANN:
 689                         if (elen >= sizeof(struct ieee80211_rann_ie))
 690                                 elems->rann = (void *)pos;
 691                         break;
 692                 case WLAN_EID_CHANNEL_SWITCH:
 693                         elems->ch_switch_elem = pos;
 694                         elems->ch_switch_elem_len = elen;
 695                         break;
 696                 case WLAN_EID_QUIET:
 697                         if (!elems->quiet_elem) {
 698                                 elems->quiet_elem = pos;
 699                                 elems->quiet_elem_len = elen;
 700                         }
 701                         elems->num_of_quiet_elem++;
 702                         break;
 703                 case WLAN_EID_COUNTRY:
 704                         elems->country_elem = pos;
 705                         elems->country_elem_len = elen;
 706                         break;
 707                 case WLAN_EID_PWR_CONSTRAINT:
 708                         elems->pwr_constr_elem = pos;
 709                         elems->pwr_constr_elem_len = elen;
 710                         break;
 711                 case WLAN_EID_TIMEOUT_INTERVAL:
 712                         elems->timeout_int = pos;
 713                         elems->timeout_int_len = elen;
 714                         break;
 715                 default:
 716                         break;
 717                 }
 718
 719                 left -= elen;
 720                 pos += elen;
 721         }
 722
 723         return crc;
 724 }
 725
 726 void ieee80211_set_wmm_default(struct ieee80211_sub_if_data *sdata)
 727 {
 728         struct ieee80211_local *local = sdata->local;
 729         struct ieee80211_tx_queue_params qparam;
 730         int queue;
 731         bool use_11b;
 732         int aCWmin, aCWmax;
 733
 734         if (!local->ops->conf_tx)
 735                 return;
 736
 737         memset(&qparam, 0, sizeof(qparam));
 738
 739         use_11b = (local->hw.conf.channel->band == IEEE80211_BAND_2GHZ) &&
 740                  !(sdata->flags & IEEE80211_SDATA_OPERATING_GMODE);
 741
 742         for (queue = 0; queue < local_to_hw(local)->queues; queue++) {
 743                 /* Set defaults according to 802.11-2007 Table 7-37 */
 744                 aCWmax = 1023;
 745                 if (use_11b)
 746                         aCWmin = 31;
 747                 else
 748                         aCWmin = 15;
 749
 750                 switch (queue) {
 751                 case 3: /* AC_BK */
 752                         qparam.cw_max = aCWmax;
 753                         qparam.cw_min = aCWmin;
 754                         qparam.txop = 0;
 755                         qparam.aifs = 7;
 756                         break;
 757                 default: /* never happens but let's not leave undefined */
 758                 case 2: /* AC_BE */
 759                         qparam.cw_max = aCWmax;
 760                         qparam.cw_min = aCWmin;
 761                         qparam.txop = 0;
 762                         qparam.aifs = 3;
 763                         break;
 764                 case 1: /* AC_VI */
 765                         qparam.cw_max = aCWmin;
 766                         qparam.cw_min = (aCWmin + 1) / 2 - 1;
 767                         if (use_11b)
 768                                 qparam.txop = 6016/32;
 769                         else
 770                                 qparam.txop = 3008/32;
 771                         qparam.aifs = 2;
 772                         break;
 773                 case 0: /* AC_VO */
 774                         qparam.cw_max = (aCWmin + 1) / 2 - 1;
 775                         qparam.cw_min = (aCWmin + 1) / 4 - 1;
 776                         if (use_11b)
 777                                 qparam.txop = 3264/32;
 778                         else
 779                                 qparam.txop = 1504/32;
 780                         qparam.aifs = 2;
 781                         break;
 782                 }
 783
 784                 drv_conf_tx(local, queue, &qparam);
 785         }
 786 }
 787
 788 void ieee80211_sta_def_wmm_params(struct ieee80211_sub_if_data *sdata,
 789                                   const size_t supp_rates_len,
 790                                   const u8 *supp_rates)
 791 {
 792         struct ieee80211_local *local = sdata->local;
 793         int i, have_higher_than_11mbit = 0;
 794
 795         /* cf. IEEE 802.11 9.2.12 */
 796         for (i = 0; i < supp_rates_len; i++)
 797                 if ((supp_rates[i] & 0x7f) * 5 > 110)
 798                         have_higher_than_11mbit = 1;
 799
 800         if (local->hw.conf.channel->band == IEEE80211_BAND_2GHZ &&
 801             have_higher_than_11mbit)
 802                 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
 803         else
 804                 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 805
 806         ieee80211_set_wmm_default(sdata);
 807 }
 808
 809 u32 ieee80211_mandatory_rates(struct ieee80211_local *local,
 810                               enum ieee80211_band band)
 811 {
 812         struct ieee80211_supported_band *sband;
 813         struct ieee80211_rate *bitrates;
 814         u32 mandatory_rates;
 815         enum ieee80211_rate_flags mandatory_flag;
 816         int i;
 817
 818         sband = local->hw.wiphy->bands[band];
 819         if (!sband) {
 820                 WARN_ON(1);
 821                 sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
 822         }
 823
 824         if (band == IEEE80211_BAND_2GHZ)
 825                 mandatory_flag = IEEE80211_RATE_MANDATORY_B;
 826         else
 827                 mandatory_flag = IEEE80211_RATE_MANDATORY_A;
 828
 829         bitrates = sband->bitrates;
 830         mandatory_rates = 0;
 831         for (i = 0; i < sband->n_bitrates; i++)
 832                 if (bitrates[i].flags & mandatory_flag)
 833                         mandatory_rates |= BIT(i);
 834         return mandatory_rates;
 835 }
 836
 837 void ieee80211_send_auth(struct ieee80211_sub_if_data *sdata,
 838                          u16 transaction, u16 auth_alg,
 839                          u8 *extra, size_t extra_len, const u8 *bssid,
 840                          const u8 *key, u8 key_len, u8 key_idx)
 841 {
 842         struct ieee80211_local *local = sdata->local;
 843         struct sk_buff *skb;
 844         struct ieee80211_mgmt *mgmt;
 845         int err;
 846
 847         skb = dev_alloc_skb(local->hw.extra_tx_headroom +
 848                             sizeof(*mgmt) + 6 + extra_len);
 849         if (!skb) {
 850                 printk(KERN_DEBUG "%s: failed to allocate buffer for auth "
 851                        "frame\n", sdata->name);
 852                 return;
 853         }
 854         skb_reserve(skb, local->hw.extra_tx_headroom);
 855
 856         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24 + 6);
 857         memset(mgmt, 0, 24 + 6);
 858         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 859                                           IEEE80211_STYPE_AUTH);
 860         memcpy(mgmt->da, bssid, ETH_ALEN);
 861         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 862         memcpy(mgmt->bssid, bssid, ETH_ALEN);
 863         mgmt->u.auth.auth_alg = cpu_to_le16(auth_alg);
 864         mgmt->u.auth.auth_transaction = cpu_to_le16(transaction);
 865         mgmt->u.auth.status_code = cpu_to_le16(0);
 866         if (extra)
 867                 memcpy(skb_put(skb, extra_len), extra, extra_len);
 868
 869         if (auth_alg == WLAN_AUTH_SHARED_KEY && transaction == 3) {
 870                 mgmt->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 871                 err = ieee80211_wep_encrypt(local, skb, key, key_len, key_idx);
 872                 WARN_ON(err);
 873         }
 874
 875         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 876         ieee80211_tx_skb(sdata, skb);
 877 }
 878
 879 int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer,
 880                              const u8 *ie, size_t ie_len,
 881                              enum ieee80211_band band)
 882 {
 883         struct ieee80211_supported_band *sband;
 884         u8 *pos;
 885         size_t offset = 0, noffset;
 886         int supp_rates_len, i;
 887
 888         sband = local->hw.wiphy->bands[band];
 889
 890         pos = buffer;
 891
 892         supp_rates_len = min_t(int, sband->n_bitrates, 8);
 893
 894         *pos++ = WLAN_EID_SUPP_RATES;
 895         *pos++ = supp_rates_len;
 896
 897         for (i = 0; i < supp_rates_len; i++) {
 898                 int rate = sband->bitrates[i].bitrate;
 899                 *pos++ = (u8) (rate / 5);
 900         }
 901
 902         /* insert "request information" if in custom IEs */
 903         if (ie && ie_len) {
 904                 static const u8 before_extrates[] = {
 905                         WLAN_EID_SSID,
 906                         WLAN_EID_SUPP_RATES,
 907                         WLAN_EID_REQUEST,
 908                 };
 909                 noffset = ieee80211_ie_split(ie, ie_len,
 910                                              before_extrates,
 911                                              ARRAY_SIZE(before_extrates),
 912                                              offset);
 913                 memcpy(pos, ie + offset, noffset - offset);
 914                 pos += noffset - offset;
 915                 offset = noffset;
 916         }
 917
 918         if (sband->n_bitrates > i) {
 919                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 920                 *pos++ = sband->n_bitrates - i;
 921
 922                 for (; i < sband->n_bitrates; i++) {
 923                         int rate = sband->bitrates[i].bitrate;
 924                         *pos++ = (u8) (rate / 5);
 925                 }
 926         }
 927
 928         /* insert custom IEs that go before HT */
 929         if (ie && ie_len) {
 930                 static const u8 before_ht[] = {
 931                         WLAN_EID_SSID,
 932                         WLAN_EID_SUPP_RATES,
 933                         WLAN_EID_REQUEST,
 934                         WLAN_EID_EXT_SUPP_RATES,
 935                         WLAN_EID_DS_PARAMS,
 936                         WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
 937                 };
 938                 noffset = ieee80211_ie_split(ie, ie_len,
 939                                              before_ht, ARRAY_SIZE(before_ht),
 940                                              offset);
 941                 memcpy(pos, ie + offset, noffset - offset);
 942                 pos += noffset - offset;
 943                 offset = noffset;
 944         }
 945
 946         if (sband->ht_cap.ht_supported) {
 947                 u16 cap = sband->ht_cap.cap;
 948                 __le16 tmp;
 949
 950                 if (ieee80211_disable_40mhz_24ghz &&
 951                     sband->band == IEEE80211_BAND_2GHZ) {
 952                         cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 953                         cap &= ~IEEE80211_HT_CAP_SGI_40;
 954                 }
 955
 956                 *pos++ = WLAN_EID_HT_CAPABILITY;
 957                 *pos++ = sizeof(struct ieee80211_ht_cap);
 958                 memset(pos, 0, sizeof(struct ieee80211_ht_cap));
 959                 tmp = cpu_to_le16(cap);
 960                 memcpy(pos, &tmp, sizeof(u16));
 961                 pos += sizeof(u16);
 962                 *pos++ = sband->ht_cap.ampdu_factor |
 963                          (sband->ht_cap.ampdu_density <<
 964                                 IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT);
 965                 memcpy(pos, &sband->ht_cap.mcs, sizeof(sband->ht_cap.mcs));
 966                 pos += sizeof(sband->ht_cap.mcs);
 967                 pos += 2 + 4 + 1; /* ext info, BF cap, antsel */
 968         }
 969
 970         /*
 971          * If adding more here, adjust code in main.c
 972          * that calculates local->scan_ies_len.
 973          */
 974
 975         /* add any remaining custom IEs */
 976         if (ie && ie_len) {
 977                 noffset = ie_len;
 978                 memcpy(pos, ie + offset, noffset - offset);
 979                 pos += noffset - offset;
 980         }
 981
 982         return pos - buffer;
 983 }
 984
 985 void ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
 986                               const u8 *ssid, size_t ssid_len,
 987                               const u8 *ie, size_t ie_len)
 988 {
 989         struct ieee80211_local *local = sdata->local;
 990         struct sk_buff *skb;
 991         struct ieee80211_mgmt *mgmt;
 992         u8 *pos;
 993
 994         skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*mgmt) + 200 +
 995                             ie_len);
 996         if (!skb) {
 997                 printk(KERN_DEBUG "%s: failed to allocate buffer for probe "
 998                        "request\n", sdata->name);
 999                 return;
1000         }
1001         skb_reserve(skb, local->hw.extra_tx_headroom);
1002
1003         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
1004         memset(mgmt, 0, 24);
1005         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1006                                           IEEE80211_STYPE_PROBE_REQ);
1007         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
1008         if (dst) {
1009                 memcpy(mgmt->da, dst, ETH_ALEN);
1010                 memcpy(mgmt->bssid, dst, ETH_ALEN);
1011         } else {
1012                 memset(mgmt->da, 0xff, ETH_ALEN);
1013                 memset(mgmt->bssid, 0xff, ETH_ALEN);
1014         }
1015         pos = skb_put(skb, 2 + ssid_len);
1016         *pos++ = WLAN_EID_SSID;
1017         *pos++ = ssid_len;
1018         memcpy(pos, ssid, ssid_len);
1019         pos += ssid_len;
1020
1021         skb_put(skb, ieee80211_build_preq_ies(local, pos, ie, ie_len,
1022                                               local->hw.conf.channel->band));
1023
1024         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1025         ieee80211_tx_skb(sdata, skb);
1026 }
1027
1028 u32 ieee80211_sta_get_rates(struct ieee80211_local *local,
1029                             struct ieee802_11_elems *elems,
1030                             enum ieee80211_band band)
1031 {
1032         struct ieee80211_supported_band *sband;
1033         struct ieee80211_rate *bitrates;
1034         size_t num_rates;
1035         u32 supp_rates;
1036         int i, j;
1037         sband = local->hw.wiphy->bands[band];
1038
1039         if (!sband) {
1040                 WARN_ON(1);
1041                 sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
1042         }
1043
1044         bitrates = sband->bitrates;
1045         num_rates = sband->n_bitrates;
1046         supp_rates = 0;
1047         for (i = 0; i < elems->supp_rates_len +
1048                      elems->ext_supp_rates_len; i++) {
1049                 u8 rate = 0;
1050                 int own_rate;
1051                 if (i < elems->supp_rates_len)
1052                         rate = elems->supp_rates[i];
1053                 else if (elems->ext_supp_rates)
1054                         rate = elems->ext_supp_rates
1055                                 [i - elems->supp_rates_len];
1056                 own_rate = 5 * (rate & 0x7f);
1057                 for (j = 0; j < num_rates; j++)
1058                         if (bitrates[j].bitrate == own_rate)
1059                                 supp_rates |= BIT(j);
1060         }
1061         return supp_rates;
1062 }
1063
1064 void ieee80211_stop_device(struct ieee80211_local *local)
1065 {
1066         ieee80211_led_radio(local, false);
1067
1068         cancel_work_sync(&local->reconfig_filter);
1069         drv_stop(local);
1070
1071         flush_workqueue(local->workqueue);
1072 }
1073
1074 int ieee80211_reconfig(struct ieee80211_local *local)
1075 {
1076         struct ieee80211_hw *hw = &local->hw;
1077         struct ieee80211_sub_if_data *sdata;
1078         struct ieee80211_if_init_conf conf;
1079         struct sta_info *sta;
1080         unsigned long flags;
1081         int res;
1082
1083         if (local->suspended)
1084                 local->resuming = true;
1085
1086         /* restart hardware */
1087         if (local->open_count) {
1088                 res = drv_start(local);
1089
1090                 ieee80211_led_radio(local, true);
1091         }
1092
1093         /* add interfaces */
1094         list_for_each_entry(sdata, &local->interfaces, list) {
1095                 if (sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
1096                     sdata->vif.type != NL80211_IFTYPE_MONITOR &&
1097                     ieee80211_sdata_running(sdata)) {
1098                         conf.vif = &sdata->vif;
1099                         conf.type = sdata->vif.type;
1100                         conf.mac_addr = sdata->vif.addr;
1101                         res = drv_add_interface(local, &conf);
1102                 }
1103         }
1104
1105         /* add STAs back */
1106         if (local->ops->sta_notify) {
1107                 spin_lock_irqsave(&local->sta_lock, flags);
1108                 list_for_each_entry(sta, &local->sta_list, list) {
1109                         sdata = sta->sdata;
1110                         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1111                                 sdata = container_of(sdata->bss,
1112                                              struct ieee80211_sub_if_data,
1113                                              u.ap);
1114
1115                         drv_sta_notify(local, sdata, STA_NOTIFY_ADD,
1116                                        &sta->sta);
1117                 }
1118                 spin_unlock_irqrestore(&local->sta_lock, flags);
1119         }
1120
1121         /* Clear Suspend state so that ADDBA requests can be processed */
1122
1123         rcu_read_lock();
1124
1125         if (hw->flags & IEEE80211_HW_AMPDU_AGGREGATION) {
1126                 list_for_each_entry_rcu(sta, &local->sta_list, list) {
1127                         clear_sta_flags(sta, WLAN_STA_SUSPEND);
1128                 }
1129         }
1130
1131         rcu_read_unlock();
1132
1133         /* setup RTS threshold */
1134         drv_set_rts_threshold(local, hw->wiphy->rts_threshold);
1135
1136         /* reconfigure hardware */
1137         ieee80211_hw_config(local, ~0);
1138
1139         ieee80211_configure_filter(local);
1140
1141         /* Finally also reconfigure all the BSS information */
1142         list_for_each_entry(sdata, &local->interfaces, list) {
1143                 u32 changed = ~0;
1144                 if (!ieee80211_sdata_running(sdata))
1145                         continue;
1146                 switch (sdata->vif.type) {
1147                 case NL80211_IFTYPE_STATION:
1148                         /* disable beacon change bits */
1149                         changed &= ~(BSS_CHANGED_BEACON |
1150                                      BSS_CHANGED_BEACON_ENABLED);
1151                         /* fall through */
1152                 case NL80211_IFTYPE_ADHOC:
1153                 case NL80211_IFTYPE_AP:
1154                 case NL80211_IFTYPE_MESH_POINT:
1155                         ieee80211_bss_info_change_notify(sdata, changed);
1156                         break;
1157                 case NL80211_IFTYPE_WDS:
1158                         break;
1159                 case NL80211_IFTYPE_AP_VLAN:
1160                 case NL80211_IFTYPE_MONITOR:
1161                         /* ignore virtual */
1162                         break;
1163                 case NL80211_IFTYPE_UNSPECIFIED:
1164                 case __NL80211_IFTYPE_AFTER_LAST:
1165                         WARN_ON(1);
1166                         break;
1167                 }
1168         }
1169
1170         /* add back keys */
1171         list_for_each_entry(sdata, &local->interfaces, list)
1172                 if (ieee80211_sdata_running(sdata))
1173                         ieee80211_enable_keys(sdata);
1174
1175         ieee80211_wake_queues_by_reason(hw,
1176                         IEEE80211_QUEUE_STOP_REASON_SUSPEND);
1177
1178         /*
1179          * If this is for hw restart things are still running.
1180          * We may want to change that later, however.
1181          */
1182         if (!local->suspended)
1183                 return 0;
1184
1185 #ifdef CONFIG_PM
1186         /* first set suspended false, then resuming */
1187         local->suspended = false;
1188         mb();
1189         local->resuming = false;
1190
1191         list_for_each_entry(sdata, &local->interfaces, list) {
1192                 switch(sdata->vif.type) {
1193                 case NL80211_IFTYPE_STATION:
1194                         ieee80211_sta_restart(sdata);
1195                         break;
1196                 case NL80211_IFTYPE_ADHOC:
1197                         ieee80211_ibss_restart(sdata);
1198                         break;
1199                 case NL80211_IFTYPE_MESH_POINT:
1200                         ieee80211_mesh_restart(sdata);
1201                         break;
1202                 default:
1203                         break;
1204                 }
1205         }
1206
1207         add_timer(&local->sta_cleanup);
1208
1209         spin_lock_irqsave(&local->sta_lock, flags);
1210         list_for_each_entry(sta, &local->sta_list, list)
1211                 mesh_plink_restart(sta);
1212         spin_unlock_irqrestore(&local->sta_lock, flags);
1213 #else
1214         WARN_ON(1);
1215 #endif
1216         return 0;
1217 }
1218
1219 static int check_mgd_smps(struct ieee80211_if_managed *ifmgd,
1220                           enum ieee80211_smps_mode *smps_mode)
1221 {
1222         if (ifmgd->associated) {
1223                 *smps_mode = ifmgd->ap_smps;
1224
1225                 if (*smps_mode == IEEE80211_SMPS_AUTOMATIC) {
1226                         if (ifmgd->powersave)
1227                                 *smps_mode = IEEE80211_SMPS_DYNAMIC;
1228                         else
1229                                 *smps_mode = IEEE80211_SMPS_OFF;
1230                 }
1231
1232                 return 1;
1233         }
1234
1235         return 0;
1236 }
1237
1238 /* must hold iflist_mtx */
1239 void ieee80211_recalc_smps(struct ieee80211_local *local,
1240                            struct ieee80211_sub_if_data *forsdata)
1241 {
1242         struct ieee80211_sub_if_data *sdata;
1243         enum ieee80211_smps_mode smps_mode = IEEE80211_SMPS_OFF;
1244         int count = 0;
1245
1246         if (forsdata)
1247                 WARN_ON(!mutex_is_locked(&forsdata->u.mgd.mtx));
1248
1249         WARN_ON(!mutex_is_locked(&local->iflist_mtx));
1250
1251         /*
1252          * This function could be improved to handle multiple
1253          * interfaces better, but right now it makes any
1254          * non-station interfaces force SM PS to be turned
1255          * off. If there are multiple station interfaces it
1256          * could also use the best possible mode, e.g. if
1257          * one is in static and the other in dynamic then
1258          * dynamic is ok.
1259          */
1260
1261         list_for_each_entry(sdata, &local->interfaces, list) {
1262                 if (!netif_running(sdata->dev))
1263                         continue;
1264                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1265                         goto set;
1266                 if (sdata != forsdata) {
1267                         /*
1268                          * This nested is ok -- we are holding the iflist_mtx
1269                          * so can't get here twice or so. But it's required
1270                          * since normally we acquire it first and then the
1271                          * iflist_mtx.
1272                          */
1273                         mutex_lock_nested(&sdata->u.mgd.mtx, SINGLE_DEPTH_NESTING);
1274                         count += check_mgd_smps(&sdata->u.mgd, &smps_mode);
1275                         mutex_unlock(&sdata->u.mgd.mtx);
1276                 } else
1277                         count += check_mgd_smps(&sdata->u.mgd, &smps_mode);
1278
1279                 if (count > 1) {
1280                         smps_mode = IEEE80211_SMPS_OFF;
1281                         break;
1282                 }
1283         }
1284
1285         if (smps_mode == local->smps_mode)
1286                 return;
1287
1288  set:
1289         local->smps_mode = smps_mode;
1290         /* changed flag is auto-detected for this */
1291         ieee80211_hw_config(local, 0);
1292 }
1293
1294 static bool ieee80211_id_in_list(const u8 *ids, int n_ids, u8 id)
1295 {
1296         int i;
1297
1298         for (i = 0; i < n_ids; i++)
1299                 if (ids[i] == id)
1300                         return true;
1301         return false;
1302 }
1303
1304 /**
1305  * ieee80211_ie_split - split an IE buffer according to ordering
1306  *
1307  * @ies: the IE buffer
1308  * @ielen: the length of the IE buffer
1309  * @ids: an array with element IDs that are allowed before
1310  *      the split
1311  * @n_ids: the size of the element ID array
1312  * @offset: offset where to start splitting in the buffer
1313  *
1314  * This function splits an IE buffer by updating the @offset
1315  * variable to point to the location where the buffer should be
1316  * split.
1317  *
1318  * It assumes that the given IE buffer is well-formed, this
1319  * has to be guaranteed by the caller!
1320  *
1321  * It also assumes that the IEs in the buffer are ordered
1322  * correctly, if not the result of using this function will not
1323  * be ordered correctly either, i.e. it does no reordering.
1324  *
1325  * The function returns the offset where the next part of the
1326  * buffer starts, which may be @ielen if the entire (remainder)
1327  * of the buffer should be used.
1328  */
1329 size_t ieee80211_ie_split(const u8 *ies, size_t ielen,
1330                           const u8 *ids, int n_ids, size_t offset)
1331 {
1332         size_t pos = offset;
1333
1334         while (pos < ielen && ieee80211_id_in_list(ids, n_ids, ies[pos]))
1335                 pos += 2 + ies[pos + 1];
1336
1337         return pos;
1338 }
1339
1340 size_t ieee80211_ie_split_vendor(const u8 *ies, size_t ielen, size_t offset)
1341 {
1342         size_t pos = offset;
1343
1344         while (pos < ielen && ies[pos] != WLAN_EID_VENDOR_SPECIFIC)
1345                 pos += 2 + ies[pos + 1];
1346
1347         return pos;
1348 }