net/mac80211/work.c

   1 /*
   2  * mac80211 work implementation
   3  *
   4  * Copyright 2003-2008, Jouni Malinen <j@w1.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  * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  */
  15
  16 #include <linux/delay.h>
  17 #include <linux/if_ether.h>
  18 #include <linux/skbuff.h>
  19 #include <linux/if_arp.h>
  20 #include <linux/etherdevice.h>
  21 #include <linux/crc32.h>
  22 #include <net/mac80211.h>
  23 #include <asm/unaligned.h>
  24
  25 #include "ieee80211_i.h"
  26 #include "rate.h"
  27
  28 #define IEEE80211_AUTH_TIMEOUT (HZ / 5)
  29 #define IEEE80211_AUTH_MAX_TRIES 3
  30 #define IEEE80211_ASSOC_TIMEOUT (HZ / 5)
  31 #define IEEE80211_ASSOC_MAX_TRIES 3
  32 #define IEEE80211_MAX_PROBE_TRIES 5
  33
  34 enum work_action {
  35         WORK_ACT_NONE,
  36         WORK_ACT_TIMEOUT,
  37         WORK_ACT_DONE,
  38 };
  39
  40
  41 /* utils */
  42 static inline void ASSERT_WORK_MTX(struct ieee80211_local *local)
  43 {
  44         WARN_ON(!mutex_is_locked(&local->work_mtx));
  45 }
  46
  47 /*
  48  * We can have multiple work items (and connection probing)
  49  * scheduling this timer, but we need to take care to only
  50  * reschedule it when it should fire _earlier_ than it was
  51  * asked for before, or if it's not pending right now. This
  52  * function ensures that. Note that it then is required to
  53  * run this function for all timeouts after the first one
  54  * has happened -- the work that runs from this timer will
  55  * do that.
  56  */
  57 static void run_again(struct ieee80211_local *local,
  58                       unsigned long timeout)
  59 {
  60         ASSERT_WORK_MTX(local);
  61
  62         if (!timer_pending(&local->work_timer) ||
  63             time_before(timeout, local->work_timer.expires))
  64                 mod_timer(&local->work_timer, timeout);
  65 }
  66
  67 static void work_free_rcu(struct rcu_head *head)
  68 {
  69         struct ieee80211_work *wk =
  70                 container_of(head, struct ieee80211_work, rcu_head);
  71
  72         kfree(wk);
  73 }
  74
  75 void free_work(struct ieee80211_work *wk)
  76 {
  77         call_rcu(&wk->rcu_head, work_free_rcu);
  78 }
  79
  80 static int ieee80211_compatible_rates(const u8 *supp_rates, int supp_rates_len,
  81                                       struct ieee80211_supported_band *sband,
  82                                       u32 *rates)
  83 {
  84         int i, j, count;
  85         *rates = 0;
  86         count = 0;
  87         for (i = 0; i < supp_rates_len; i++) {
  88                 int rate = (supp_rates[i] & 0x7F) * 5;
  89
  90                 for (j = 0; j < sband->n_bitrates; j++)
  91                         if (sband->bitrates[j].bitrate == rate) {
  92                                 *rates |= BIT(j);
  93                                 count++;
  94                                 break;
  95                         }
  96         }
  97
  98         return count;
  99 }
 100
 101 /* frame sending functions */
 102
 103 static void ieee80211_add_ht_ie(struct sk_buff *skb, const u8 *ht_info_ie,
 104                                 struct ieee80211_supported_band *sband,
 105                                 struct ieee80211_channel *channel,
 106                                 enum ieee80211_smps_mode smps)
 107 {
 108         struct ieee80211_ht_info *ht_info;
 109         u8 *pos;
 110         u32 flags = channel->flags;
 111         u16 cap = sband->ht_cap.cap;
 112         __le16 tmp;
 113
 114         if (!sband->ht_cap.ht_supported)
 115                 return;
 116
 117         if (!ht_info_ie)
 118                 return;
 119
 120         if (ht_info_ie[1] < sizeof(struct ieee80211_ht_info))
 121                 return;
 122
 123         ht_info = (struct ieee80211_ht_info *)(ht_info_ie + 2);
 124
 125         /* determine capability flags */
 126
 127         if (ieee80211_disable_40mhz_24ghz &&
 128             sband->band == IEEE80211_BAND_2GHZ) {
 129                 cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 130                 cap &= ~IEEE80211_HT_CAP_SGI_40;
 131         }
 132
 133         switch (ht_info->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) {
 134         case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
 135                 if (flags & IEEE80211_CHAN_NO_HT40PLUS) {
 136                         cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 137                         cap &= ~IEEE80211_HT_CAP_SGI_40;
 138                 }
 139                 break;
 140         case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
 141                 if (flags & IEEE80211_CHAN_NO_HT40MINUS) {
 142                         cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 143                         cap &= ~IEEE80211_HT_CAP_SGI_40;
 144                 }
 145                 break;
 146         }
 147
 148         /* set SM PS mode properly */
 149         cap &= ~IEEE80211_HT_CAP_SM_PS;
 150         switch (smps) {
 151         case IEEE80211_SMPS_AUTOMATIC:
 152         case IEEE80211_SMPS_NUM_MODES:
 153                 WARN_ON(1);
 154         case IEEE80211_SMPS_OFF:
 155                 cap |= WLAN_HT_CAP_SM_PS_DISABLED <<
 156                         IEEE80211_HT_CAP_SM_PS_SHIFT;
 157                 break;
 158         case IEEE80211_SMPS_STATIC:
 159                 cap |= WLAN_HT_CAP_SM_PS_STATIC <<
 160                         IEEE80211_HT_CAP_SM_PS_SHIFT;
 161                 break;
 162         case IEEE80211_SMPS_DYNAMIC:
 163                 cap |= WLAN_HT_CAP_SM_PS_DYNAMIC <<
 164                         IEEE80211_HT_CAP_SM_PS_SHIFT;
 165                 break;
 166         }
 167
 168         /* reserve and fill IE */
 169
 170         pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
 171         *pos++ = WLAN_EID_HT_CAPABILITY;
 172         *pos++ = sizeof(struct ieee80211_ht_cap);
 173         memset(pos, 0, sizeof(struct ieee80211_ht_cap));
 174
 175         /* capability flags */
 176         tmp = cpu_to_le16(cap);
 177         memcpy(pos, &tmp, sizeof(u16));
 178         pos += sizeof(u16);
 179
 180         /* AMPDU parameters */
 181         *pos++ = sband->ht_cap.ampdu_factor |
 182                  (sband->ht_cap.ampdu_density <<
 183                         IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT);
 184
 185         /* MCS set */
 186         memcpy(pos, &sband->ht_cap.mcs, sizeof(sband->ht_cap.mcs));
 187         pos += sizeof(sband->ht_cap.mcs);
 188
 189         /* extended capabilities */
 190         pos += sizeof(__le16);
 191
 192         /* BF capabilities */
 193         pos += sizeof(__le32);
 194
 195         /* antenna selection */
 196         pos += sizeof(u8);
 197 }
 198
 199 static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata,
 200                                  struct ieee80211_work *wk)
 201 {
 202         struct ieee80211_local *local = sdata->local;
 203         struct sk_buff *skb;
 204         struct ieee80211_mgmt *mgmt;
 205         u8 *pos;
 206         const u8 *ies;
 207         size_t offset = 0, noffset;
 208         int i, len, count, rates_len, supp_rates_len;
 209         u16 capab;
 210         struct ieee80211_supported_band *sband;
 211         u32 rates = 0;
 212
 213         sband = local->hw.wiphy->bands[wk->chan->band];
 214
 215         /*
 216          * Get all rates supported by the device and the AP as
 217          * some APs don't like getting a superset of their rates
 218          * in the association request (e.g. D-Link DAP 1353 in
 219          * b-only mode)...
 220          */
 221         rates_len = ieee80211_compatible_rates(wk->assoc.supp_rates,
 222                                                wk->assoc.supp_rates_len,
 223                                                sband, &rates);
 224
 225         skb = alloc_skb(local->hw.extra_tx_headroom +
 226                         sizeof(*mgmt) + /* bit too much but doesn't matter */
 227                         2 + wk->assoc.ssid_len + /* SSID */
 228                         4 + rates_len + /* (extended) rates */
 229                         4 + /* power capability */
 230                         2 + 2 * sband->n_channels + /* supported channels */
 231                         2 + sizeof(struct ieee80211_ht_cap) + /* HT */
 232                         wk->ie_len + /* extra IEs */
 233                         9, /* WMM */
 234                         GFP_KERNEL);
 235         if (!skb) {
 236                 printk(KERN_DEBUG "%s: failed to allocate buffer for assoc "
 237                        "frame\n", sdata->name);
 238                 return;
 239         }
 240         skb_reserve(skb, local->hw.extra_tx_headroom);
 241
 242         capab = WLAN_CAPABILITY_ESS;
 243
 244         if (sband->band == IEEE80211_BAND_2GHZ) {
 245                 if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE))
 246                         capab |= WLAN_CAPABILITY_SHORT_SLOT_TIME;
 247                 if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_PREAMBLE_INCAPABLE))
 248                         capab |= WLAN_CAPABILITY_SHORT_PREAMBLE;
 249         }
 250
 251         if (wk->assoc.capability & WLAN_CAPABILITY_PRIVACY)
 252                 capab |= WLAN_CAPABILITY_PRIVACY;
 253
 254         if ((wk->assoc.capability & WLAN_CAPABILITY_SPECTRUM_MGMT) &&
 255             (local->hw.flags & IEEE80211_HW_SPECTRUM_MGMT))
 256                 capab |= WLAN_CAPABILITY_SPECTRUM_MGMT;
 257
 258         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 259         memset(mgmt, 0, 24);
 260         memcpy(mgmt->da, wk->filter_ta, ETH_ALEN);
 261         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 262         memcpy(mgmt->bssid, wk->filter_ta, ETH_ALEN);
 263
 264         if (!is_zero_ether_addr(wk->assoc.prev_bssid)) {
 265                 skb_put(skb, 10);
 266                 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 267                                                   IEEE80211_STYPE_REASSOC_REQ);
 268                 mgmt->u.reassoc_req.capab_info = cpu_to_le16(capab);
 269                 mgmt->u.reassoc_req.listen_interval =
 270                                 cpu_to_le16(local->hw.conf.listen_interval);
 271                 memcpy(mgmt->u.reassoc_req.current_ap, wk->assoc.prev_bssid,
 272                        ETH_ALEN);
 273         } else {
 274                 skb_put(skb, 4);
 275                 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 276                                                   IEEE80211_STYPE_ASSOC_REQ);
 277                 mgmt->u.assoc_req.capab_info = cpu_to_le16(capab);
 278                 mgmt->u.assoc_req.listen_interval =
 279                                 cpu_to_le16(local->hw.conf.listen_interval);
 280         }
 281
 282         /* SSID */
 283         ies = pos = skb_put(skb, 2 + wk->assoc.ssid_len);
 284         *pos++ = WLAN_EID_SSID;
 285         *pos++ = wk->assoc.ssid_len;
 286         memcpy(pos, wk->assoc.ssid, wk->assoc.ssid_len);
 287
 288         /* add all rates which were marked to be used above */
 289         supp_rates_len = rates_len;
 290         if (supp_rates_len > 8)
 291                 supp_rates_len = 8;
 292
 293         len = sband->n_bitrates;
 294         pos = skb_put(skb, supp_rates_len + 2);
 295         *pos++ = WLAN_EID_SUPP_RATES;
 296         *pos++ = supp_rates_len;
 297
 298         count = 0;
 299         for (i = 0; i < sband->n_bitrates; i++) {
 300                 if (BIT(i) & rates) {
 301                         int rate = sband->bitrates[i].bitrate;
 302                         *pos++ = (u8) (rate / 5);
 303                         if (++count == 8)
 304                                 break;
 305                 }
 306         }
 307
 308         if (rates_len > count) {
 309                 pos = skb_put(skb, rates_len - count + 2);
 310                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 311                 *pos++ = rates_len - count;
 312
 313                 for (i++; i < sband->n_bitrates; i++) {
 314                         if (BIT(i) & rates) {
 315                                 int rate = sband->bitrates[i].bitrate;
 316                                 *pos++ = (u8) (rate / 5);
 317                         }
 318                 }
 319         }
 320
 321         if (capab & WLAN_CAPABILITY_SPECTRUM_MGMT) {
 322                 /* 1. power capabilities */
 323                 pos = skb_put(skb, 4);
 324                 *pos++ = WLAN_EID_PWR_CAPABILITY;
 325                 *pos++ = 2;
 326                 *pos++ = 0; /* min tx power */
 327                 *pos++ = wk->chan->max_power; /* max tx power */
 328
 329                 /* 2. supported channels */
 330                 /* TODO: get this in reg domain format */
 331                 pos = skb_put(skb, 2 * sband->n_channels + 2);
 332                 *pos++ = WLAN_EID_SUPPORTED_CHANNELS;
 333                 *pos++ = 2 * sband->n_channels;
 334                 for (i = 0; i < sband->n_channels; i++) {
 335                         *pos++ = ieee80211_frequency_to_channel(
 336                                         sband->channels[i].center_freq);
 337                         *pos++ = 1; /* one channel in the subband*/
 338                 }
 339         }
 340
 341         /* if present, add any custom IEs that go before HT */
 342         if (wk->ie_len && wk->ie) {
 343                 static const u8 before_ht[] = {
 344                         WLAN_EID_SSID,
 345                         WLAN_EID_SUPP_RATES,
 346                         WLAN_EID_EXT_SUPP_RATES,
 347                         WLAN_EID_PWR_CAPABILITY,
 348                         WLAN_EID_SUPPORTED_CHANNELS,
 349                         WLAN_EID_RSN,
 350                         WLAN_EID_QOS_CAPA,
 351                         WLAN_EID_RRM_ENABLED_CAPABILITIES,
 352                         WLAN_EID_MOBILITY_DOMAIN,
 353                         WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
 354                 };
 355                 noffset = ieee80211_ie_split(wk->ie, wk->ie_len,
 356                                              before_ht, ARRAY_SIZE(before_ht),
 357                                              offset);
 358                 pos = skb_put(skb, noffset - offset);
 359                 memcpy(pos, wk->ie + offset, noffset - offset);
 360                 offset = noffset;
 361         }
 362
 363         if (wk->assoc.use_11n && wk->assoc.wmm_used &&
 364             local->hw.queues >= 4)
 365                 ieee80211_add_ht_ie(skb, wk->assoc.ht_information_ie,
 366                                     sband, wk->chan, wk->assoc.smps);
 367
 368         /* if present, add any custom non-vendor IEs that go after HT */
 369         if (wk->ie_len && wk->ie) {
 370                 noffset = ieee80211_ie_split_vendor(wk->ie, wk->ie_len,
 371                                                     offset);
 372                 pos = skb_put(skb, noffset - offset);
 373                 memcpy(pos, wk->ie + offset, noffset - offset);
 374                 offset = noffset;
 375         }
 376
 377         if (wk->assoc.wmm_used && local->hw.queues >= 4) {
 378                 pos = skb_put(skb, 9);
 379                 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
 380                 *pos++ = 7; /* len */
 381                 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
 382                 *pos++ = 0x50;
 383                 *pos++ = 0xf2;
 384                 *pos++ = 2; /* WME */
 385                 *pos++ = 0; /* WME info */
 386                 *pos++ = 1; /* WME ver */
 387                 *pos++ = 0;
 388         }
 389
 390         /* add any remaining custom (i.e. vendor specific here) IEs */
 391         if (wk->ie_len && wk->ie) {
 392                 noffset = wk->ie_len;
 393                 pos = skb_put(skb, noffset - offset);
 394                 memcpy(pos, wk->ie + offset, noffset - offset);
 395         }
 396
 397         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 398         ieee80211_tx_skb(sdata, skb);
 399 }
 400
 401 static void ieee80211_remove_auth_bss(struct ieee80211_local *local,
 402                                       struct ieee80211_work *wk)
 403 {
 404         struct cfg80211_bss *cbss;
 405         u16 capa_val = WLAN_CAPABILITY_ESS;
 406
 407         if (wk->probe_auth.privacy)
 408                 capa_val |= WLAN_CAPABILITY_PRIVACY;
 409
 410         cbss = cfg80211_get_bss(local->hw.wiphy, wk->chan, wk->filter_ta,
 411                                 wk->probe_auth.ssid, wk->probe_auth.ssid_len,
 412                                 WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_PRIVACY,
 413                                 capa_val);
 414         if (!cbss)
 415                 return;
 416
 417         cfg80211_unlink_bss(local->hw.wiphy, cbss);
 418         cfg80211_put_bss(cbss);
 419 }
 420
 421 static enum work_action __must_check
 422 ieee80211_direct_probe(struct ieee80211_work *wk)
 423 {
 424         struct ieee80211_sub_if_data *sdata = wk->sdata;
 425         struct ieee80211_local *local = sdata->local;
 426
 427         wk->probe_auth.tries++;
 428         if (wk->probe_auth.tries > IEEE80211_AUTH_MAX_TRIES) {
 429                 printk(KERN_DEBUG "%s: direct probe to %pM timed out\n",
 430                        sdata->name, wk->filter_ta);
 431
 432                 /*
 433                  * Most likely AP is not in the range so remove the
 434                  * bss struct for that AP.
 435                  */
 436                 ieee80211_remove_auth_bss(local, wk);
 437
 438                 return WORK_ACT_TIMEOUT;
 439         }
 440
 441         printk(KERN_DEBUG "%s: direct probe to %pM (try %d)\n",
 442                         sdata->name, wk->filter_ta, wk->probe_auth.tries);
 443
 444         /*
 445          * Direct probe is sent to broadcast address as some APs
 446          * will not answer to direct packet in unassociated state.
 447          */
 448         ieee80211_send_probe_req(sdata, NULL, wk->probe_auth.ssid,
 449                                  wk->probe_auth.ssid_len, NULL, 0);
 450
 451         wk->timeout = jiffies + IEEE80211_AUTH_TIMEOUT;
 452         run_again(local, wk->timeout);
 453
 454         return WORK_ACT_NONE;
 455 }
 456
 457
 458 static enum work_action __must_check
 459 ieee80211_authenticate(struct ieee80211_work *wk)
 460 {
 461         struct ieee80211_sub_if_data *sdata = wk->sdata;
 462         struct ieee80211_local *local = sdata->local;
 463
 464         wk->probe_auth.tries++;
 465         if (wk->probe_auth.tries > IEEE80211_AUTH_MAX_TRIES) {
 466                 printk(KERN_DEBUG "%s: authentication with %pM"
 467                        " timed out\n", sdata->name, wk->filter_ta);
 468
 469                 /*
 470                  * Most likely AP is not in the range so remove the
 471                  * bss struct for that AP.
 472                  */
 473                 ieee80211_remove_auth_bss(local, wk);
 474
 475                 return WORK_ACT_TIMEOUT;
 476         }
 477
 478         printk(KERN_DEBUG "%s: authenticate with %pM (try %d)\n",
 479                sdata->name, wk->filter_ta, wk->probe_auth.tries);
 480
 481         ieee80211_send_auth(sdata, 1, wk->probe_auth.algorithm, wk->ie,
 482                             wk->ie_len, wk->filter_ta, NULL, 0, 0);
 483         wk->probe_auth.transaction = 2;
 484
 485         wk->timeout = jiffies + IEEE80211_AUTH_TIMEOUT;
 486         run_again(local, wk->timeout);
 487
 488         return WORK_ACT_NONE;
 489 }
 490
 491 static enum work_action __must_check
 492 ieee80211_associate(struct ieee80211_work *wk)
 493 {
 494         struct ieee80211_sub_if_data *sdata = wk->sdata;
 495         struct ieee80211_local *local = sdata->local;
 496
 497         wk->assoc.tries++;
 498         if (wk->assoc.tries > IEEE80211_ASSOC_MAX_TRIES) {
 499                 printk(KERN_DEBUG "%s: association with %pM"
 500                        " timed out\n",
 501                        sdata->name, wk->filter_ta);
 502
 503                 /*
 504                  * Most likely AP is not in the range so remove the
 505                  * bss struct for that AP.
 506                  */
 507                 if (wk->assoc.bss)
 508                         cfg80211_unlink_bss(local->hw.wiphy, wk->assoc.bss);
 509
 510                 return WORK_ACT_TIMEOUT;
 511         }
 512
 513         printk(KERN_DEBUG "%s: associate with %pM (try %d)\n",
 514                sdata->name, wk->filter_ta, wk->assoc.tries);
 515         ieee80211_send_assoc(sdata, wk);
 516
 517         wk->timeout = jiffies + IEEE80211_ASSOC_TIMEOUT;
 518         run_again(local, wk->timeout);
 519
 520         return WORK_ACT_NONE;
 521 }
 522
 523 static enum work_action __must_check
 524 ieee80211_remain_on_channel_timeout(struct ieee80211_work *wk)
 525 {
 526         /*
 527          * First time we run, do nothing -- the generic code will
 528          * have switched to the right channel etc.
 529          */
 530         if (!wk->remain.started) {
 531                 wk->remain.started = true;
 532                 wk->timeout = jiffies + msecs_to_jiffies(wk->remain.duration);
 533
 534                 cfg80211_ready_on_channel(wk->sdata->dev, (u64)wk, wk->chan,
 535                                           wk->chan_type, wk->remain.duration,
 536                                           GFP_KERNEL);
 537
 538                 return WORK_ACT_NONE;
 539         }
 540
 541         return WORK_ACT_TIMEOUT;
 542 }
 543
 544 static void ieee80211_auth_challenge(struct ieee80211_work *wk,
 545                                      struct ieee80211_mgmt *mgmt,
 546                                      size_t len)
 547 {
 548         struct ieee80211_sub_if_data *sdata = wk->sdata;
 549         u8 *pos;
 550         struct ieee802_11_elems elems;
 551
 552         pos = mgmt->u.auth.variable;
 553         ieee802_11_parse_elems(pos, len - (pos - (u8 *) mgmt), &elems);
 554         if (!elems.challenge)
 555                 return;
 556         ieee80211_send_auth(sdata, 3, wk->probe_auth.algorithm,
 557                             elems.challenge - 2, elems.challenge_len + 2,
 558                             wk->filter_ta, wk->probe_auth.key,
 559                             wk->probe_auth.key_len, wk->probe_auth.key_idx);
 560         wk->probe_auth.transaction = 4;
 561 }
 562
 563 static enum work_action __must_check
 564 ieee80211_rx_mgmt_auth(struct ieee80211_work *wk,
 565                        struct ieee80211_mgmt *mgmt, size_t len)
 566 {
 567         u16 auth_alg, auth_transaction, status_code;
 568
 569         if (wk->type != IEEE80211_WORK_AUTH)
 570                 return WORK_ACT_NONE;
 571
 572         if (len < 24 + 6)
 573                 return WORK_ACT_NONE;
 574
 575         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 576         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 577         status_code = le16_to_cpu(mgmt->u.auth.status_code);
 578
 579         if (auth_alg != wk->probe_auth.algorithm ||
 580             auth_transaction != wk->probe_auth.transaction)
 581                 return WORK_ACT_NONE;
 582
 583         if (status_code != WLAN_STATUS_SUCCESS) {
 584                 printk(KERN_DEBUG "%s: %pM denied authentication (status %d)\n",
 585                        wk->sdata->name, mgmt->sa, status_code);
 586                 return WORK_ACT_DONE;
 587         }
 588
 589         switch (wk->probe_auth.algorithm) {
 590         case WLAN_AUTH_OPEN:
 591         case WLAN_AUTH_LEAP:
 592         case WLAN_AUTH_FT:
 593                 break;
 594         case WLAN_AUTH_SHARED_KEY:
 595                 if (wk->probe_auth.transaction != 4) {
 596                         ieee80211_auth_challenge(wk, mgmt, len);
 597                         /* need another frame */
 598                         return WORK_ACT_NONE;
 599                 }
 600                 break;
 601         default:
 602                 WARN_ON(1);
 603                 return WORK_ACT_NONE;
 604         }
 605
 606         printk(KERN_DEBUG "%s: authenticated\n", wk->sdata->name);
 607         return WORK_ACT_DONE;
 608 }
 609
 610 static enum work_action __must_check
 611 ieee80211_rx_mgmt_assoc_resp(struct ieee80211_work *wk,
 612                              struct ieee80211_mgmt *mgmt, size_t len,
 613                              bool reassoc)
 614 {
 615         struct ieee80211_sub_if_data *sdata = wk->sdata;
 616         struct ieee80211_local *local = sdata->local;
 617         u16 capab_info, status_code, aid;
 618         struct ieee802_11_elems elems;
 619         u8 *pos;
 620
 621         /*
 622          * AssocResp and ReassocResp have identical structure, so process both
 623          * of them in this function.
 624          */
 625
 626         if (len < 24 + 6)
 627                 return WORK_ACT_NONE;
 628
 629         capab_info = le16_to_cpu(mgmt->u.assoc_resp.capab_info);
 630         status_code = le16_to_cpu(mgmt->u.assoc_resp.status_code);
 631         aid = le16_to_cpu(mgmt->u.assoc_resp.aid);
 632
 633         printk(KERN_DEBUG "%s: RX %sssocResp from %pM (capab=0x%x "
 634                "status=%d aid=%d)\n",
 635                sdata->name, reassoc ? "Rea" : "A", mgmt->sa,
 636                capab_info, status_code, (u16)(aid & ~(BIT(15) | BIT(14))));
 637
 638         pos = mgmt->u.assoc_resp.variable;
 639         ieee802_11_parse_elems(pos, len - (pos - (u8 *) mgmt), &elems);
 640
 641         if (status_code == WLAN_STATUS_ASSOC_REJECTED_TEMPORARILY &&
 642             elems.timeout_int && elems.timeout_int_len == 5 &&
 643             elems.timeout_int[0] == WLAN_TIMEOUT_ASSOC_COMEBACK) {
 644                 u32 tu, ms;
 645                 tu = get_unaligned_le32(elems.timeout_int + 1);
 646                 ms = tu * 1024 / 1000;
 647                 printk(KERN_DEBUG "%s: %pM rejected association temporarily; "
 648                        "comeback duration %u TU (%u ms)\n",
 649                        sdata->name, mgmt->sa, tu, ms);
 650                 wk->timeout = jiffies + msecs_to_jiffies(ms);
 651                 if (ms > IEEE80211_ASSOC_TIMEOUT)
 652                         run_again(local, wk->timeout);
 653                 return WORK_ACT_NONE;
 654         }
 655
 656         if (status_code != WLAN_STATUS_SUCCESS)
 657                 printk(KERN_DEBUG "%s: %pM denied association (code=%d)\n",
 658                        sdata->name, mgmt->sa, status_code);
 659         else
 660                 printk(KERN_DEBUG "%s: associated\n", sdata->name);
 661
 662         return WORK_ACT_DONE;
 663 }
 664
 665 static enum work_action __must_check
 666 ieee80211_rx_mgmt_probe_resp(struct ieee80211_work *wk,
 667                              struct ieee80211_mgmt *mgmt, size_t len,
 668                              struct ieee80211_rx_status *rx_status)
 669 {
 670         struct ieee80211_sub_if_data *sdata = wk->sdata;
 671         struct ieee80211_local *local = sdata->local;
 672         size_t baselen;
 673
 674         ASSERT_WORK_MTX(local);
 675
 676         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
 677         if (baselen > len)
 678                 return WORK_ACT_NONE;
 679
 680         printk(KERN_DEBUG "%s: direct probe responded\n", sdata->name);
 681         return WORK_ACT_DONE;
 682 }
 683
 684 static void ieee80211_work_rx_queued_mgmt(struct ieee80211_local *local,
 685                                           struct sk_buff *skb)
 686 {
 687         struct ieee80211_rx_status *rx_status;
 688         struct ieee80211_mgmt *mgmt;
 689         struct ieee80211_work *wk;
 690         enum work_action rma = WORK_ACT_NONE;
 691         u16 fc;
 692
 693         rx_status = (struct ieee80211_rx_status *) skb->cb;
 694         mgmt = (struct ieee80211_mgmt *) skb->data;
 695         fc = le16_to_cpu(mgmt->frame_control);
 696
 697         mutex_lock(&local->work_mtx);
 698
 699         list_for_each_entry(wk, &local->work_list, list) {
 700                 const u8 *bssid = NULL;
 701
 702                 switch (wk->type) {
 703                 case IEEE80211_WORK_DIRECT_PROBE:
 704                 case IEEE80211_WORK_AUTH:
 705                 case IEEE80211_WORK_ASSOC:
 706                         bssid = wk->filter_ta;
 707                         break;
 708                 default:
 709                         continue;
 710                 }
 711
 712                 /*
 713                  * Before queuing, we already verified mgmt->sa,
 714                  * so this is needed just for matching.
 715                  */
 716                 if (compare_ether_addr(bssid, mgmt->bssid))
 717                         continue;
 718
 719                 switch (fc & IEEE80211_FCTL_STYPE) {
 720                 case IEEE80211_STYPE_PROBE_RESP:
 721                         rma = ieee80211_rx_mgmt_probe_resp(wk, mgmt, skb->len,
 722                                                            rx_status);
 723                         break;
 724                 case IEEE80211_STYPE_AUTH:
 725                         rma = ieee80211_rx_mgmt_auth(wk, mgmt, skb->len);
 726                         break;
 727                 case IEEE80211_STYPE_ASSOC_RESP:
 728                         rma = ieee80211_rx_mgmt_assoc_resp(wk, mgmt,
 729                                                            skb->len, false);
 730                         break;
 731                 case IEEE80211_STYPE_REASSOC_RESP:
 732                         rma = ieee80211_rx_mgmt_assoc_resp(wk, mgmt,
 733                                                            skb->len, true);
 734                         break;
 735                 default:
 736                         WARN_ON(1);
 737                 }
 738                 /*
 739                  * We've processed this frame for that work, so it can't
 740                  * belong to another work struct.
 741                  * NB: this is also required for correctness for 'rma'!
 742                  */
 743                 break;
 744         }
 745
 746         switch (rma) {
 747         case WORK_ACT_NONE:
 748                 break;
 749         case WORK_ACT_DONE:
 750                 list_del_rcu(&wk->list);
 751                 break;
 752         default:
 753                 WARN(1, "unexpected: %d", rma);
 754         }
 755
 756         mutex_unlock(&local->work_mtx);
 757
 758         if (rma != WORK_ACT_DONE)
 759                 goto out;
 760
 761         switch (wk->done(wk, skb)) {
 762         case WORK_DONE_DESTROY:
 763                 free_work(wk);
 764                 break;
 765         case WORK_DONE_REQUEUE:
 766                 synchronize_rcu();
 767                 wk->started = false; /* restart */
 768                 mutex_lock(&local->work_mtx);
 769                 list_add_tail(&wk->list, &local->work_list);
 770                 mutex_unlock(&local->work_mtx);
 771         }
 772
 773  out:
 774         kfree_skb(skb);
 775 }
 776
 777 static void ieee80211_work_timer(unsigned long data)
 778 {
 779         struct ieee80211_local *local = (void *) data;
 780
 781         if (local->quiescing)
 782                 return;
 783
 784         ieee80211_queue_work(&local->hw, &local->work_work);
 785 }
 786
 787 static void ieee80211_work_work(struct work_struct *work)
 788 {
 789         struct ieee80211_local *local =
 790                 container_of(work, struct ieee80211_local, work_work);
 791         struct sk_buff *skb;
 792         struct ieee80211_work *wk, *tmp;
 793         LIST_HEAD(free_work);
 794         enum work_action rma;
 795         bool remain_off_channel = false;
 796
 797         if (local->scanning)
 798                 return;
 799
 800         /*
 801          * ieee80211_queue_work() should have picked up most cases,
 802          * here we'll pick the the rest.
 803          */
 804         if (WARN(local->suspended, "work scheduled while going to suspend\n"))
 805                 return;
 806
 807         /* first process frames to avoid timing out while a frame is pending */
 808         while ((skb = skb_dequeue(&local->work_skb_queue)))
 809                 ieee80211_work_rx_queued_mgmt(local, skb);
 810
 811         ieee80211_recalc_idle(local);
 812
 813         mutex_lock(&local->work_mtx);
 814
 815         list_for_each_entry_safe(wk, tmp, &local->work_list, list) {
 816                 /* mark work as started if it's on the current off-channel */
 817                 if (!wk->started && local->tmp_channel &&
 818                     wk->chan == local->tmp_channel &&
 819                     wk->chan_type == local->tmp_channel_type) {
 820                         wk->started = true;
 821                 }
 822
 823                 if (!wk->started && !local->tmp_channel) {
 824                         /*
 825                          * TODO: could optimize this by leaving the
 826                          *       station vifs in awake mode if they
 827                          *       happen to be on the same channel as
 828                          *       the requested channel
 829                          */
 830                         ieee80211_offchannel_stop_beaconing(local);
 831                         ieee80211_offchannel_stop_station(local);
 832
 833                         local->tmp_channel = wk->chan;
 834                         local->tmp_channel_type = wk->chan_type;
 835                         ieee80211_hw_config(local, 0);
 836                         wk->started = true;
 837                         wk->timeout = jiffies;
 838                 }
 839
 840                 /* don't try to work with items that aren't started */
 841                 if (!wk->started)
 842                         continue;
 843
 844                 if (time_is_after_jiffies(wk->timeout)) {
 845                         /*
 846                          * This work item isn't supposed to be worked on
 847                          * right now, but take care to adjust the timer
 848                          * properly.
 849                          */
 850                         run_again(local, wk->timeout);
 851                         continue;
 852                 }
 853
 854                 switch (wk->type) {
 855                 default:
 856                         WARN_ON(1);
 857                         /* nothing */
 858                         rma = WORK_ACT_NONE;
 859                         break;
 860                 case IEEE80211_WORK_ABORT:
 861                         rma = WORK_ACT_TIMEOUT;
 862                 case IEEE80211_WORK_DIRECT_PROBE:
 863                         rma = ieee80211_direct_probe(wk);
 864                         break;
 865                 case IEEE80211_WORK_AUTH:
 866                         rma = ieee80211_authenticate(wk);
 867                         break;
 868                 case IEEE80211_WORK_ASSOC:
 869                         rma = ieee80211_associate(wk);
 870                         break;
 871                 case IEEE80211_WORK_REMAIN_ON_CHANNEL:
 872                         rma = ieee80211_remain_on_channel_timeout(wk);
 873                         break;
 874                 }
 875
 876                 switch (rma) {
 877                 case WORK_ACT_NONE:
 878                         /* might have changed the timeout */
 879                         run_again(local, wk->timeout);
 880                         break;
 881                 case WORK_ACT_TIMEOUT:
 882                         list_del_rcu(&wk->list);
 883                         synchronize_rcu();
 884                         list_add(&wk->list, &free_work);
 885                         break;
 886                 default:
 887                         WARN(1, "unexpected: %d", rma);
 888                 }
 889         }
 890
 891         list_for_each_entry(wk, &local->work_list, list) {
 892                 if (!wk->started)
 893                         continue;
 894                 if (wk->chan != local->tmp_channel)
 895                         continue;
 896                 if (wk->chan_type != local->tmp_channel_type)
 897                         continue;
 898                 remain_off_channel = true;
 899         }
 900
 901         if (!remain_off_channel && local->tmp_channel) {
 902                 local->tmp_channel = NULL;
 903                 ieee80211_hw_config(local, 0);
 904                 ieee80211_offchannel_return(local, true);
 905                 /* give connection some time to breathe */
 906                 run_again(local, jiffies + HZ/2);
 907         }
 908
 909         if (list_empty(&local->work_list) && local->scan_req)
 910                 ieee80211_queue_delayed_work(&local->hw,
 911                                              &local->scan_work,
 912                                              round_jiffies_relative(0));
 913
 914         mutex_unlock(&local->work_mtx);
 915
 916         ieee80211_recalc_idle(local);
 917
 918         list_for_each_entry_safe(wk, tmp, &free_work, list) {
 919                 wk->done(wk, NULL);
 920                 list_del(&wk->list);
 921                 kfree(wk);
 922         }
 923 }
 924
 925 void ieee80211_add_work(struct ieee80211_work *wk)
 926 {
 927         struct ieee80211_local *local;
 928
 929         if (WARN_ON(!wk->chan))
 930                 return;
 931
 932         if (WARN_ON(!wk->sdata))
 933                 return;
 934
 935         if (WARN_ON(!wk->done))
 936                 return;
 937
 938         wk->started = false;
 939
 940         local = wk->sdata->local;
 941         mutex_lock(&local->work_mtx);
 942         list_add_tail(&wk->list, &local->work_list);
 943         mutex_unlock(&local->work_mtx);
 944
 945         ieee80211_queue_work(&local->hw, &local->work_work);
 946 }
 947
 948 void ieee80211_work_init(struct ieee80211_local *local)
 949 {
 950         mutex_init(&local->work_mtx);
 951         INIT_LIST_HEAD(&local->work_list);
 952         setup_timer(&local->work_timer, ieee80211_work_timer,
 953                     (unsigned long)local);
 954         INIT_WORK(&local->work_work, ieee80211_work_work);
 955         skb_queue_head_init(&local->work_skb_queue);
 956 }
 957
 958 void ieee80211_work_purge(struct ieee80211_sub_if_data *sdata)
 959 {
 960         struct ieee80211_local *local = sdata->local;
 961         struct ieee80211_work *wk;
 962
 963         mutex_lock(&local->work_mtx);
 964         list_for_each_entry(wk, &local->work_list, list) {
 965                 if (wk->sdata != sdata)
 966                         continue;
 967                 wk->type = IEEE80211_WORK_ABORT;
 968                 wk->started = true;
 969                 wk->timeout = jiffies;
 970         }
 971         mutex_unlock(&local->work_mtx);
 972
 973         /* run cleanups etc. */
 974         ieee80211_work_work(&local->work_work);
 975
 976         mutex_lock(&local->work_mtx);
 977         list_for_each_entry(wk, &local->work_list, list) {
 978                 if (wk->sdata != sdata)
 979                         continue;
 980                 WARN_ON(1);
 981                 break;
 982         }
 983         mutex_unlock(&local->work_mtx);
 984 }
 985
 986 ieee80211_rx_result ieee80211_work_rx_mgmt(struct ieee80211_sub_if_data *sdata,
 987                                            struct sk_buff *skb)
 988 {
 989         struct ieee80211_local *local = sdata->local;
 990         struct ieee80211_mgmt *mgmt;
 991         struct ieee80211_work *wk;
 992         u16 fc;
 993
 994         if (skb->len < 24)
 995                 return RX_DROP_MONITOR;
 996
 997         mgmt = (struct ieee80211_mgmt *) skb->data;
 998         fc = le16_to_cpu(mgmt->frame_control);
 999
1000         list_for_each_entry_rcu(wk, &local->work_list, list) {
1001                 if (sdata != wk->sdata)
1002                         continue;
1003                 if (compare_ether_addr(wk->filter_ta, mgmt->sa))
1004                         continue;
1005                 if (compare_ether_addr(wk->filter_ta, mgmt->bssid))
1006                         continue;
1007
1008                 switch (fc & IEEE80211_FCTL_STYPE) {
1009                 case IEEE80211_STYPE_AUTH:
1010                 case IEEE80211_STYPE_PROBE_RESP:
1011                 case IEEE80211_STYPE_ASSOC_RESP:
1012                 case IEEE80211_STYPE_REASSOC_RESP:
1013                 case IEEE80211_STYPE_DEAUTH:
1014                 case IEEE80211_STYPE_DISASSOC:
1015                         skb_queue_tail(&local->work_skb_queue, skb);
1016                         ieee80211_queue_work(&local->hw, &local->work_work);
1017                         return RX_QUEUED;
1018                 }
1019         }
1020
1021         return RX_CONTINUE;
1022 }
1023
1024 static enum work_done_result ieee80211_remain_done(struct ieee80211_work *wk,
1025                                                    struct sk_buff *skb)
1026 {
1027         /*
1028          * We are done serving the remain-on-channel command.
1029          */
1030         cfg80211_remain_on_channel_expired(wk->sdata->dev, (u64)wk,
1031                                            wk->chan, wk->chan_type,
1032                                            GFP_KERNEL);
1033
1034         return WORK_DONE_DESTROY;
1035 }
1036
1037 int ieee80211_wk_remain_on_channel(struct ieee80211_sub_if_data *sdata,
1038                                    struct ieee80211_channel *chan,
1039                                    enum nl80211_channel_type channel_type,
1040                                    unsigned int duration, u64 *cookie)
1041 {
1042         struct ieee80211_work *wk;
1043
1044         wk = kzalloc(sizeof(*wk), GFP_KERNEL);
1045         if (!wk)
1046                 return -ENOMEM;
1047
1048         wk->type = IEEE80211_WORK_REMAIN_ON_CHANNEL;
1049         wk->chan = chan;
1050         wk->chan_type = channel_type;
1051         wk->sdata = sdata;
1052         wk->done = ieee80211_remain_done;
1053
1054         wk->remain.duration = duration;
1055
1056         *cookie = (u64)wk;
1057
1058         ieee80211_add_work(wk);
1059
1060         return 0;
1061 }
1062
1063 int ieee80211_wk_cancel_remain_on_channel(struct ieee80211_sub_if_data *sdata,
1064                                           u64 cookie)
1065 {
1066         struct ieee80211_local *local = sdata->local;
1067         struct ieee80211_work *wk, *tmp;
1068         bool found = false;
1069
1070         mutex_lock(&local->work_mtx);
1071         list_for_each_entry_safe(wk, tmp, &local->work_list, list) {
1072                 if ((u64)wk == cookie) {
1073                         wk->timeout = jiffies;
1074                         found = true;
1075                         break;
1076                 }
1077         }
1078         mutex_unlock(&local->work_mtx);
1079
1080         if (!found)
1081                 return -ENOENT;
1082
1083         ieee80211_queue_work(&local->hw, &local->work_work);
1084
1085         return 0;
1086 }