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 <linux/slab.h>
  23 #include <net/mac80211.h>
  24 #include <asm/unaligned.h>
  25
  26 #include "ieee80211_i.h"
  27 #include "rate.h"
  28
  29 #define IEEE80211_AUTH_TIMEOUT (HZ / 5)
  30 #define IEEE80211_AUTH_MAX_TRIES 3
  31 #define IEEE80211_ASSOC_TIMEOUT (HZ / 5)
  32 #define IEEE80211_ASSOC_MAX_TRIES 3
  33 #define IEEE80211_MAX_PROBE_TRIES 5
  34
  35 enum work_action {
  36         WORK_ACT_NONE,
  37         WORK_ACT_TIMEOUT,
  38         WORK_ACT_DONE,
  39 };
  40
  41
  42 /* utils */
  43 static inline void ASSERT_WORK_MTX(struct ieee80211_local *local)
  44 {
  45         WARN_ON(!mutex_is_locked(&local->work_mtx));
  46 }
  47
  48 /*
  49  * We can have multiple work items (and connection probing)
  50  * scheduling this timer, but we need to take care to only
  51  * reschedule it when it should fire _earlier_ than it was
  52  * asked for before, or if it's not pending right now. This
  53  * function ensures that. Note that it then is required to
  54  * run this function for all timeouts after the first one
  55  * has happened -- the work that runs from this timer will
  56  * do that.
  57  */
  58 static void run_again(struct ieee80211_local *local,
  59                       unsigned long timeout)
  60 {
  61         ASSERT_WORK_MTX(local);
  62
  63         if (!timer_pending(&local->work_timer) ||
  64             time_before(timeout, local->work_timer.expires))
  65                 mod_timer(&local->work_timer, timeout);
  66 }
  67
  68 static void work_free_rcu(struct rcu_head *head)
  69 {
  70         struct ieee80211_work *wk =
  71                 container_of(head, struct ieee80211_work, rcu_head);
  72
  73         kfree(wk);
  74 }
  75
  76 void free_work(struct ieee80211_work *wk)
  77 {
  78         call_rcu(&wk->rcu_head, work_free_rcu);
  79 }
  80
  81 static int ieee80211_compatible_rates(const u8 *supp_rates, int supp_rates_len,
  82                                       struct ieee80211_supported_band *sband,
  83                                       u32 *rates)
  84 {
  85         int i, j, count;
  86         *rates = 0;
  87         count = 0;
  88         for (i = 0; i < supp_rates_len; i++) {
  89                 int rate = (supp_rates[i] & 0x7F) * 5;
  90
  91                 for (j = 0; j < sband->n_bitrates; j++)
  92                         if (sband->bitrates[j].bitrate == rate) {
  93                                 *rates |= BIT(j);
  94                                 count++;
  95                                 break;
  96                         }
  97         }
  98
  99         return count;
 100 }
 101
 102 /* frame sending functions */
 103
 104 static void ieee80211_add_ht_ie(struct sk_buff *skb, const u8 *ht_info_ie,
 105                                 struct ieee80211_supported_band *sband,
 106                                 struct ieee80211_channel *channel,
 107                                 enum ieee80211_smps_mode smps)
 108 {
 109         struct ieee80211_ht_info *ht_info;
 110         u8 *pos;
 111         u32 flags = channel->flags;
 112         u16 cap = sband->ht_cap.cap;
 113         __le16 tmp;
 114
 115         if (!sband->ht_cap.ht_supported)
 116                 return;
 117
 118         if (!ht_info_ie)
 119                 return;
 120
 121         if (ht_info_ie[1] < sizeof(struct ieee80211_ht_info))
 122                 return;
 123
 124         ht_info = (struct ieee80211_ht_info *)(ht_info_ie + 2);
 125
 126         /* determine capability flags */
 127
 128         if (ieee80211_disable_40mhz_24ghz &&
 129             sband->band == IEEE80211_BAND_2GHZ) {
 130                 cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 131                 cap &= ~IEEE80211_HT_CAP_SGI_40;
 132         }
 133
 134         switch (ht_info->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) {
 135         case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
 136                 if (flags & IEEE80211_CHAN_NO_HT40PLUS) {
 137                         cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 138                         cap &= ~IEEE80211_HT_CAP_SGI_40;
 139                 }
 140                 break;
 141         case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
 142                 if (flags & IEEE80211_CHAN_NO_HT40MINUS) {
 143                         cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 144                         cap &= ~IEEE80211_HT_CAP_SGI_40;
 145                 }
 146                 break;
 147         }
 148
 149         /* set SM PS mode properly */
 150         cap &= ~IEEE80211_HT_CAP_SM_PS;
 151         switch (smps) {
 152         case IEEE80211_SMPS_AUTOMATIC:
 153         case IEEE80211_SMPS_NUM_MODES:
 154                 WARN_ON(1);
 155         case IEEE80211_SMPS_OFF:
 156                 cap |= WLAN_HT_CAP_SM_PS_DISABLED <<
 157                         IEEE80211_HT_CAP_SM_PS_SHIFT;
 158                 break;
 159         case IEEE80211_SMPS_STATIC:
 160                 cap |= WLAN_HT_CAP_SM_PS_STATIC <<
 161                         IEEE80211_HT_CAP_SM_PS_SHIFT;
 162                 break;
 163         case IEEE80211_SMPS_DYNAMIC:
 164                 cap |= WLAN_HT_CAP_SM_PS_DYNAMIC <<
 165                         IEEE80211_HT_CAP_SM_PS_SHIFT;
 166                 break;
 167         }
 168
 169         /* reserve and fill IE */
 170
 171         pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
 172         *pos++ = WLAN_EID_HT_CAPABILITY;
 173         *pos++ = sizeof(struct ieee80211_ht_cap);
 174         memset(pos, 0, sizeof(struct ieee80211_ht_cap));
 175
 176         /* capability flags */
 177         tmp = cpu_to_le16(cap);
 178         memcpy(pos, &tmp, sizeof(u16));
 179         pos += sizeof(u16);
 180
 181         /* AMPDU parameters */
 182         *pos++ = sband->ht_cap.ampdu_factor |
 183                  (sband->ht_cap.ampdu_density <<
 184                         IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT);
 185
 186         /* MCS set */
 187         memcpy(pos, &sband->ht_cap.mcs, sizeof(sband->ht_cap.mcs));
 188         pos += sizeof(sband->ht_cap.mcs);
 189
 190         /* extended capabilities */
 191         pos += sizeof(__le16);
 192
 193         /* BF capabilities */
 194         pos += sizeof(__le32);
 195
 196         /* antenna selection */
 197         pos += sizeof(u8);
 198 }
 199
 200 static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata,
 201                                  struct ieee80211_work *wk)
 202 {
 203         struct ieee80211_local *local = sdata->local;
 204         struct sk_buff *skb;
 205         struct ieee80211_mgmt *mgmt;
 206         u8 *pos, qos_info;
 207         const u8 *ies;
 208         size_t offset = 0, noffset;
 209         int i, len, count, rates_len, supp_rates_len;
 210         u16 capab;
 211         struct ieee80211_supported_band *sband;
 212         u32 rates = 0;
 213
 214         sband = local->hw.wiphy->bands[wk->chan->band];
 215
 216         /*
 217          * Get all rates supported by the device and the AP as
 218          * some APs don't like getting a superset of their rates
 219          * in the association request (e.g. D-Link DAP 1353 in
 220          * b-only mode)...
 221          */
 222         rates_len = ieee80211_compatible_rates(wk->assoc.supp_rates,
 223                                                wk->assoc.supp_rates_len,
 224                                                sband, &rates);
 225
 226         skb = alloc_skb(local->hw.extra_tx_headroom +
 227                         sizeof(*mgmt) + /* bit too much but doesn't matter */
 228                         2 + wk->assoc.ssid_len + /* SSID */
 229                         4 + rates_len + /* (extended) rates */
 230                         4 + /* power capability */
 231                         2 + 2 * sband->n_channels + /* supported channels */
 232                         2 + sizeof(struct ieee80211_ht_cap) + /* HT */
 233                         wk->ie_len + /* extra IEs */
 234                         9, /* WMM */
 235                         GFP_KERNEL);
 236         if (!skb) {
 237                 printk(KERN_DEBUG "%s: failed to allocate buffer for assoc "
 238                        "frame\n", sdata->name);
 239                 return;
 240         }
 241         skb_reserve(skb, local->hw.extra_tx_headroom);
 242
 243         capab = WLAN_CAPABILITY_ESS;
 244
 245         if (sband->band == IEEE80211_BAND_2GHZ) {
 246                 if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE))
 247                         capab |= WLAN_CAPABILITY_SHORT_SLOT_TIME;
 248                 if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_PREAMBLE_INCAPABLE))
 249                         capab |= WLAN_CAPABILITY_SHORT_PREAMBLE;
 250         }
 251
 252         if (wk->assoc.capability & WLAN_CAPABILITY_PRIVACY)
 253                 capab |= WLAN_CAPABILITY_PRIVACY;
 254
 255         if ((wk->assoc.capability & WLAN_CAPABILITY_SPECTRUM_MGMT) &&
 256             (local->hw.flags & IEEE80211_HW_SPECTRUM_MGMT))
 257                 capab |= WLAN_CAPABILITY_SPECTRUM_MGMT;
 258
 259         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 260         memset(mgmt, 0, 24);
 261         memcpy(mgmt->da, wk->filter_ta, ETH_ALEN);
 262         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 263         memcpy(mgmt->bssid, wk->filter_ta, ETH_ALEN);
 264
 265         if (!is_zero_ether_addr(wk->assoc.prev_bssid)) {
 266                 skb_put(skb, 10);
 267                 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 268                                                   IEEE80211_STYPE_REASSOC_REQ);
 269                 mgmt->u.reassoc_req.capab_info = cpu_to_le16(capab);
 270                 mgmt->u.reassoc_req.listen_interval =
 271                                 cpu_to_le16(local->hw.conf.listen_interval);
 272                 memcpy(mgmt->u.reassoc_req.current_ap, wk->assoc.prev_bssid,
 273                        ETH_ALEN);
 274         } else {
 275                 skb_put(skb, 4);
 276                 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 277                                                   IEEE80211_STYPE_ASSOC_REQ);
 278                 mgmt->u.assoc_req.capab_info = cpu_to_le16(capab);
 279                 mgmt->u.assoc_req.listen_interval =
 280                                 cpu_to_le16(local->hw.conf.listen_interval);
 281         }
 282
 283         /* SSID */
 284         ies = pos = skb_put(skb, 2 + wk->assoc.ssid_len);
 285         *pos++ = WLAN_EID_SSID;
 286         *pos++ = wk->assoc.ssid_len;
 287         memcpy(pos, wk->assoc.ssid, wk->assoc.ssid_len);
 288
 289         /* add all rates which were marked to be used above */
 290         supp_rates_len = rates_len;
 291         if (supp_rates_len > 8)
 292                 supp_rates_len = 8;
 293
 294         len = sband->n_bitrates;
 295         pos = skb_put(skb, supp_rates_len + 2);
 296         *pos++ = WLAN_EID_SUPP_RATES;
 297         *pos++ = supp_rates_len;
 298
 299         count = 0;
 300         for (i = 0; i < sband->n_bitrates; i++) {
 301                 if (BIT(i) & rates) {
 302                         int rate = sband->bitrates[i].bitrate;
 303                         *pos++ = (u8) (rate / 5);
 304                         if (++count == 8)
 305                                 break;
 306                 }
 307         }
 308
 309         if (rates_len > count) {
 310                 pos = skb_put(skb, rates_len - count + 2);
 311                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 312                 *pos++ = rates_len - count;
 313
 314                 for (i++; i < sband->n_bitrates; i++) {
 315                         if (BIT(i) & rates) {
 316                                 int rate = sband->bitrates[i].bitrate;
 317                                 *pos++ = (u8) (rate / 5);
 318                         }
 319                 }
 320         }
 321
 322         if (capab & WLAN_CAPABILITY_SPECTRUM_MGMT) {
 323                 /* 1. power capabilities */
 324                 pos = skb_put(skb, 4);
 325                 *pos++ = WLAN_EID_PWR_CAPABILITY;
 326                 *pos++ = 2;
 327                 *pos++ = 0; /* min tx power */
 328                 *pos++ = wk->chan->max_power; /* max tx power */
 329
 330                 /* 2. supported channels */
 331                 /* TODO: get this in reg domain format */
 332                 pos = skb_put(skb, 2 * sband->n_channels + 2);
 333                 *pos++ = WLAN_EID_SUPPORTED_CHANNELS;
 334                 *pos++ = 2 * sband->n_channels;
 335                 for (i = 0; i < sband->n_channels; i++) {
 336                         *pos++ = ieee80211_frequency_to_channel(
 337                                         sband->channels[i].center_freq);
 338                         *pos++ = 1; /* one channel in the subband*/
 339                 }
 340         }
 341
 342         /* if present, add any custom IEs that go before HT */
 343         if (wk->ie_len && wk->ie) {
 344                 static const u8 before_ht[] = {
 345                         WLAN_EID_SSID,
 346                         WLAN_EID_SUPP_RATES,
 347                         WLAN_EID_EXT_SUPP_RATES,
 348                         WLAN_EID_PWR_CAPABILITY,
 349                         WLAN_EID_SUPPORTED_CHANNELS,
 350                         WLAN_EID_RSN,
 351                         WLAN_EID_QOS_CAPA,
 352                         WLAN_EID_RRM_ENABLED_CAPABILITIES,
 353                         WLAN_EID_MOBILITY_DOMAIN,
 354                         WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
 355                 };
 356                 noffset = ieee80211_ie_split(wk->ie, wk->ie_len,
 357                                              before_ht, ARRAY_SIZE(before_ht),
 358                                              offset);
 359                 pos = skb_put(skb, noffset - offset);
 360                 memcpy(pos, wk->ie + offset, noffset - offset);
 361                 offset = noffset;
 362         }
 363
 364         if (wk->assoc.use_11n && wk->assoc.wmm_used &&
 365             local->hw.queues >= 4)
 366                 ieee80211_add_ht_ie(skb, wk->assoc.ht_information_ie,
 367                                     sband, wk->chan, wk->assoc.smps);
 368
 369         /* if present, add any custom non-vendor IEs that go after HT */
 370         if (wk->ie_len && wk->ie) {
 371                 noffset = ieee80211_ie_split_vendor(wk->ie, wk->ie_len,
 372                                                     offset);
 373                 pos = skb_put(skb, noffset - offset);
 374                 memcpy(pos, wk->ie + offset, noffset - offset);
 375                 offset = noffset;
 376         }
 377
 378         if (wk->assoc.wmm_used && local->hw.queues >= 4) {
 379                 if (wk->assoc.uapsd_used) {
 380                         qos_info = local->uapsd_queues;
 381                         qos_info |= (local->uapsd_max_sp_len <<
 382                                      IEEE80211_WMM_IE_STA_QOSINFO_SP_SHIFT);
 383                 } else {
 384                         qos_info = 0;
 385                 }
 386
 387                 pos = skb_put(skb, 9);
 388                 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
 389                 *pos++ = 7; /* len */
 390                 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
 391                 *pos++ = 0x50;
 392                 *pos++ = 0xf2;
 393                 *pos++ = 2; /* WME */
 394                 *pos++ = 0; /* WME info */
 395                 *pos++ = 1; /* WME ver */
 396                 *pos++ = qos_info;
 397         }
 398
 399         /* add any remaining custom (i.e. vendor specific here) IEs */
 400         if (wk->ie_len && wk->ie) {
 401                 noffset = wk->ie_len;
 402                 pos = skb_put(skb, noffset - offset);
 403                 memcpy(pos, wk->ie + offset, noffset - offset);
 404         }
 405
 406         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 407         ieee80211_tx_skb(sdata, skb);
 408 }
 409
 410 static void ieee80211_remove_auth_bss(struct ieee80211_local *local,
 411                                       struct ieee80211_work *wk)
 412 {
 413         struct cfg80211_bss *cbss;
 414         u16 capa_val = WLAN_CAPABILITY_ESS;
 415
 416         if (wk->probe_auth.privacy)
 417                 capa_val |= WLAN_CAPABILITY_PRIVACY;
 418
 419         cbss = cfg80211_get_bss(local->hw.wiphy, wk->chan, wk->filter_ta,
 420                                 wk->probe_auth.ssid, wk->probe_auth.ssid_len,
 421                                 WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_PRIVACY,
 422                                 capa_val);
 423         if (!cbss)
 424                 return;
 425
 426         cfg80211_unlink_bss(local->hw.wiphy, cbss);
 427         cfg80211_put_bss(cbss);
 428 }
 429
 430 static enum work_action __must_check
 431 ieee80211_direct_probe(struct ieee80211_work *wk)
 432 {
 433         struct ieee80211_sub_if_data *sdata = wk->sdata;
 434         struct ieee80211_local *local = sdata->local;
 435
 436         wk->probe_auth.tries++;
 437         if (wk->probe_auth.tries > IEEE80211_AUTH_MAX_TRIES) {
 438                 printk(KERN_DEBUG "%s: direct probe to %pM timed out\n",
 439                        sdata->name, wk->filter_ta);
 440
 441                 /*
 442                  * Most likely AP is not in the range so remove the
 443                  * bss struct for that AP.
 444                  */
 445                 ieee80211_remove_auth_bss(local, wk);
 446
 447                 return WORK_ACT_TIMEOUT;
 448         }
 449
 450         printk(KERN_DEBUG "%s: direct probe to %pM (try %d)\n",
 451                         sdata->name, wk->filter_ta, wk->probe_auth.tries);
 452
 453         /*
 454          * Direct probe is sent to broadcast address as some APs
 455          * will not answer to direct packet in unassociated state.
 456          */
 457         ieee80211_send_probe_req(sdata, NULL, wk->probe_auth.ssid,
 458                                  wk->probe_auth.ssid_len, NULL, 0);
 459
 460         wk->timeout = jiffies + IEEE80211_AUTH_TIMEOUT;
 461         run_again(local, wk->timeout);
 462
 463         return WORK_ACT_NONE;
 464 }
 465
 466
 467 static enum work_action __must_check
 468 ieee80211_authenticate(struct ieee80211_work *wk)
 469 {
 470         struct ieee80211_sub_if_data *sdata = wk->sdata;
 471         struct ieee80211_local *local = sdata->local;
 472
 473         wk->probe_auth.tries++;
 474         if (wk->probe_auth.tries > IEEE80211_AUTH_MAX_TRIES) {
 475                 printk(KERN_DEBUG "%s: authentication with %pM"
 476                        " timed out\n", sdata->name, wk->filter_ta);
 477
 478                 /*
 479                  * Most likely AP is not in the range so remove the
 480                  * bss struct for that AP.
 481                  */
 482                 ieee80211_remove_auth_bss(local, wk);
 483
 484                 return WORK_ACT_TIMEOUT;
 485         }
 486
 487         printk(KERN_DEBUG "%s: authenticate with %pM (try %d)\n",
 488                sdata->name, wk->filter_ta, wk->probe_auth.tries);
 489
 490         ieee80211_send_auth(sdata, 1, wk->probe_auth.algorithm, wk->ie,
 491                             wk->ie_len, wk->filter_ta, NULL, 0, 0);
 492         wk->probe_auth.transaction = 2;
 493
 494         wk->timeout = jiffies + IEEE80211_AUTH_TIMEOUT;
 495         run_again(local, wk->timeout);
 496
 497         return WORK_ACT_NONE;
 498 }
 499
 500 static enum work_action __must_check
 501 ieee80211_associate(struct ieee80211_work *wk)
 502 {
 503         struct ieee80211_sub_if_data *sdata = wk->sdata;
 504         struct ieee80211_local *local = sdata->local;
 505
 506         wk->assoc.tries++;
 507         if (wk->assoc.tries > IEEE80211_ASSOC_MAX_TRIES) {
 508                 printk(KERN_DEBUG "%s: association with %pM"
 509                        " timed out\n",
 510                        sdata->name, wk->filter_ta);
 511
 512                 /*
 513                  * Most likely AP is not in the range so remove the
 514                  * bss struct for that AP.
 515                  */
 516                 if (wk->assoc.bss)
 517                         cfg80211_unlink_bss(local->hw.wiphy, wk->assoc.bss);
 518
 519                 return WORK_ACT_TIMEOUT;
 520         }
 521
 522         printk(KERN_DEBUG "%s: associate with %pM (try %d)\n",
 523                sdata->name, wk->filter_ta, wk->assoc.tries);
 524         ieee80211_send_assoc(sdata, wk);
 525
 526         wk->timeout = jiffies + IEEE80211_ASSOC_TIMEOUT;
 527         run_again(local, wk->timeout);
 528
 529         return WORK_ACT_NONE;
 530 }
 531
 532 static enum work_action __must_check
 533 ieee80211_remain_on_channel_timeout(struct ieee80211_work *wk)
 534 {
 535         /*
 536          * First time we run, do nothing -- the generic code will
 537          * have switched to the right channel etc.
 538          */
 539         if (!wk->started) {
 540                 wk->timeout = jiffies + msecs_to_jiffies(wk->remain.duration);
 541
 542                 cfg80211_ready_on_channel(wk->sdata->dev, (unsigned long) wk,
 543                                           wk->chan, wk->chan_type,
 544                                           wk->remain.duration, GFP_KERNEL);
 545
 546                 return WORK_ACT_NONE;
 547         }
 548
 549         return WORK_ACT_TIMEOUT;
 550 }
 551
 552 static void ieee80211_auth_challenge(struct ieee80211_work *wk,
 553                                      struct ieee80211_mgmt *mgmt,
 554                                      size_t len)
 555 {
 556         struct ieee80211_sub_if_data *sdata = wk->sdata;
 557         u8 *pos;
 558         struct ieee802_11_elems elems;
 559
 560         pos = mgmt->u.auth.variable;
 561         ieee802_11_parse_elems(pos, len - (pos - (u8 *) mgmt), &elems);
 562         if (!elems.challenge)
 563                 return;
 564         ieee80211_send_auth(sdata, 3, wk->probe_auth.algorithm,
 565                             elems.challenge - 2, elems.challenge_len + 2,
 566                             wk->filter_ta, wk->probe_auth.key,
 567                             wk->probe_auth.key_len, wk->probe_auth.key_idx);
 568         wk->probe_auth.transaction = 4;
 569 }
 570
 571 static enum work_action __must_check
 572 ieee80211_rx_mgmt_auth(struct ieee80211_work *wk,
 573                        struct ieee80211_mgmt *mgmt, size_t len)
 574 {
 575         u16 auth_alg, auth_transaction, status_code;
 576
 577         if (wk->type != IEEE80211_WORK_AUTH)
 578                 return WORK_ACT_NONE;
 579
 580         if (len < 24 + 6)
 581                 return WORK_ACT_NONE;
 582
 583         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 584         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 585         status_code = le16_to_cpu(mgmt->u.auth.status_code);
 586
 587         if (auth_alg != wk->probe_auth.algorithm ||
 588             auth_transaction != wk->probe_auth.transaction)
 589                 return WORK_ACT_NONE;
 590
 591         if (status_code != WLAN_STATUS_SUCCESS) {
 592                 printk(KERN_DEBUG "%s: %pM denied authentication (status %d)\n",
 593                        wk->sdata->name, mgmt->sa, status_code);
 594                 return WORK_ACT_DONE;
 595         }
 596
 597         switch (wk->probe_auth.algorithm) {
 598         case WLAN_AUTH_OPEN:
 599         case WLAN_AUTH_LEAP:
 600         case WLAN_AUTH_FT:
 601                 break;
 602         case WLAN_AUTH_SHARED_KEY:
 603                 if (wk->probe_auth.transaction != 4) {
 604                         ieee80211_auth_challenge(wk, mgmt, len);
 605                         /* need another frame */
 606                         return WORK_ACT_NONE;
 607                 }
 608                 break;
 609         default:
 610                 WARN_ON(1);
 611                 return WORK_ACT_NONE;
 612         }
 613
 614         printk(KERN_DEBUG "%s: authenticated\n", wk->sdata->name);
 615         return WORK_ACT_DONE;
 616 }
 617
 618 static enum work_action __must_check
 619 ieee80211_rx_mgmt_assoc_resp(struct ieee80211_work *wk,
 620                              struct ieee80211_mgmt *mgmt, size_t len,
 621                              bool reassoc)
 622 {
 623         struct ieee80211_sub_if_data *sdata = wk->sdata;
 624         struct ieee80211_local *local = sdata->local;
 625         u16 capab_info, status_code, aid;
 626         struct ieee802_11_elems elems;
 627         u8 *pos;
 628
 629         /*
 630          * AssocResp and ReassocResp have identical structure, so process both
 631          * of them in this function.
 632          */
 633
 634         if (len < 24 + 6)
 635                 return WORK_ACT_NONE;
 636
 637         capab_info = le16_to_cpu(mgmt->u.assoc_resp.capab_info);
 638         status_code = le16_to_cpu(mgmt->u.assoc_resp.status_code);
 639         aid = le16_to_cpu(mgmt->u.assoc_resp.aid);
 640
 641         printk(KERN_DEBUG "%s: RX %sssocResp from %pM (capab=0x%x "
 642                "status=%d aid=%d)\n",
 643                sdata->name, reassoc ? "Rea" : "A", mgmt->sa,
 644                capab_info, status_code, (u16)(aid & ~(BIT(15) | BIT(14))));
 645
 646         pos = mgmt->u.assoc_resp.variable;
 647         ieee802_11_parse_elems(pos, len - (pos - (u8 *) mgmt), &elems);
 648
 649         if (status_code == WLAN_STATUS_ASSOC_REJECTED_TEMPORARILY &&
 650             elems.timeout_int && elems.timeout_int_len == 5 &&
 651             elems.timeout_int[0] == WLAN_TIMEOUT_ASSOC_COMEBACK) {
 652                 u32 tu, ms;
 653                 tu = get_unaligned_le32(elems.timeout_int + 1);
 654                 ms = tu * 1024 / 1000;
 655                 printk(KERN_DEBUG "%s: %pM rejected association temporarily; "
 656                        "comeback duration %u TU (%u ms)\n",
 657                        sdata->name, mgmt->sa, tu, ms);
 658                 wk->timeout = jiffies + msecs_to_jiffies(ms);
 659                 if (ms > IEEE80211_ASSOC_TIMEOUT)
 660                         run_again(local, wk->timeout);
 661                 return WORK_ACT_NONE;
 662         }
 663
 664         if (status_code != WLAN_STATUS_SUCCESS)
 665                 printk(KERN_DEBUG "%s: %pM denied association (code=%d)\n",
 666                        sdata->name, mgmt->sa, status_code);
 667         else
 668                 printk(KERN_DEBUG "%s: associated\n", sdata->name);
 669
 670         return WORK_ACT_DONE;
 671 }
 672
 673 static enum work_action __must_check
 674 ieee80211_rx_mgmt_probe_resp(struct ieee80211_work *wk,
 675                              struct ieee80211_mgmt *mgmt, size_t len,
 676                              struct ieee80211_rx_status *rx_status)
 677 {
 678         struct ieee80211_sub_if_data *sdata = wk->sdata;
 679         struct ieee80211_local *local = sdata->local;
 680         size_t baselen;
 681
 682         ASSERT_WORK_MTX(local);
 683
 684         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
 685         if (baselen > len)
 686                 return WORK_ACT_NONE;
 687
 688         printk(KERN_DEBUG "%s: direct probe responded\n", sdata->name);
 689         return WORK_ACT_DONE;
 690 }
 691
 692 static void ieee80211_work_rx_queued_mgmt(struct ieee80211_local *local,
 693                                           struct sk_buff *skb)
 694 {
 695         struct ieee80211_rx_status *rx_status;
 696         struct ieee80211_mgmt *mgmt;
 697         struct ieee80211_work *wk;
 698         enum work_action rma = WORK_ACT_NONE;
 699         u16 fc;
 700
 701         rx_status = (struct ieee80211_rx_status *) skb->cb;
 702         mgmt = (struct ieee80211_mgmt *) skb->data;
 703         fc = le16_to_cpu(mgmt->frame_control);
 704
 705         mutex_lock(&local->work_mtx);
 706
 707         list_for_each_entry(wk, &local->work_list, list) {
 708                 const u8 *bssid = NULL;
 709
 710                 switch (wk->type) {
 711                 case IEEE80211_WORK_DIRECT_PROBE:
 712                 case IEEE80211_WORK_AUTH:
 713                 case IEEE80211_WORK_ASSOC:
 714                         bssid = wk->filter_ta;
 715                         break;
 716                 default:
 717                         continue;
 718                 }
 719
 720                 /*
 721                  * Before queuing, we already verified mgmt->sa,
 722                  * so this is needed just for matching.
 723                  */
 724                 if (compare_ether_addr(bssid, mgmt->bssid))
 725                         continue;
 726
 727                 switch (fc & IEEE80211_FCTL_STYPE) {
 728                 case IEEE80211_STYPE_PROBE_RESP:
 729                         rma = ieee80211_rx_mgmt_probe_resp(wk, mgmt, skb->len,
 730                                                            rx_status);
 731                         break;
 732                 case IEEE80211_STYPE_AUTH:
 733                         rma = ieee80211_rx_mgmt_auth(wk, mgmt, skb->len);
 734                         break;
 735                 case IEEE80211_STYPE_ASSOC_RESP:
 736                         rma = ieee80211_rx_mgmt_assoc_resp(wk, mgmt,
 737                                                            skb->len, false);
 738                         break;
 739                 case IEEE80211_STYPE_REASSOC_RESP:
 740                         rma = ieee80211_rx_mgmt_assoc_resp(wk, mgmt,
 741                                                            skb->len, true);
 742                         break;
 743                 default:
 744                         WARN_ON(1);
 745                 }
 746                 /*
 747                  * We've processed this frame for that work, so it can't
 748                  * belong to another work struct.
 749                  * NB: this is also required for correctness for 'rma'!
 750                  */
 751                 break;
 752         }
 753
 754         switch (rma) {
 755         case WORK_ACT_NONE:
 756                 break;
 757         case WORK_ACT_DONE:
 758                 list_del_rcu(&wk->list);
 759                 break;
 760         default:
 761                 WARN(1, "unexpected: %d", rma);
 762         }
 763
 764         mutex_unlock(&local->work_mtx);
 765
 766         if (rma != WORK_ACT_DONE)
 767                 goto out;
 768
 769         switch (wk->done(wk, skb)) {
 770         case WORK_DONE_DESTROY:
 771                 free_work(wk);
 772                 break;
 773         case WORK_DONE_REQUEUE:
 774                 synchronize_rcu();
 775                 wk->started = false; /* restart */
 776                 mutex_lock(&local->work_mtx);
 777                 list_add_tail(&wk->list, &local->work_list);
 778                 mutex_unlock(&local->work_mtx);
 779         }
 780
 781  out:
 782         kfree_skb(skb);
 783 }
 784
 785 static void ieee80211_work_timer(unsigned long data)
 786 {
 787         struct ieee80211_local *local = (void *) data;
 788
 789         if (local->quiescing)
 790                 return;
 791
 792         ieee80211_queue_work(&local->hw, &local->work_work);
 793 }
 794
 795 static void ieee80211_work_work(struct work_struct *work)
 796 {
 797         struct ieee80211_local *local =
 798                 container_of(work, struct ieee80211_local, work_work);
 799         struct sk_buff *skb;
 800         struct ieee80211_work *wk, *tmp;
 801         LIST_HEAD(free_work);
 802         enum work_action rma;
 803         bool remain_off_channel = false;
 804
 805         if (local->scanning)
 806                 return;
 807
 808         /*
 809          * ieee80211_queue_work() should have picked up most cases,
 810          * here we'll pick the the rest.
 811          */
 812         if (WARN(local->suspended, "work scheduled while going to suspend\n"))
 813                 return;
 814
 815         /* first process frames to avoid timing out while a frame is pending */
 816         while ((skb = skb_dequeue(&local->work_skb_queue)))
 817                 ieee80211_work_rx_queued_mgmt(local, skb);
 818
 819         ieee80211_recalc_idle(local);
 820
 821         mutex_lock(&local->work_mtx);
 822
 823         list_for_each_entry_safe(wk, tmp, &local->work_list, list) {
 824                 bool started = wk->started;
 825
 826                 /* mark work as started if it's on the current off-channel */
 827                 if (!started && local->tmp_channel &&
 828                     wk->chan == local->tmp_channel &&
 829                     wk->chan_type == local->tmp_channel_type) {
 830                         started = true;
 831                         wk->timeout = jiffies;
 832                 }
 833
 834                 if (!started && !local->tmp_channel) {
 835                         /*
 836                          * TODO: could optimize this by leaving the
 837                          *       station vifs in awake mode if they
 838                          *       happen to be on the same channel as
 839                          *       the requested channel
 840                          */
 841                         ieee80211_offchannel_stop_beaconing(local);
 842                         ieee80211_offchannel_stop_station(local);
 843
 844                         local->tmp_channel = wk->chan;
 845                         local->tmp_channel_type = wk->chan_type;
 846                         ieee80211_hw_config(local, 0);
 847                         started = true;
 848                         wk->timeout = jiffies;
 849                 }
 850
 851                 /* don't try to work with items that aren't started */
 852                 if (!started)
 853                         continue;
 854
 855                 if (time_is_after_jiffies(wk->timeout)) {
 856                         /*
 857                          * This work item isn't supposed to be worked on
 858                          * right now, but take care to adjust the timer
 859                          * properly.
 860                          */
 861                         run_again(local, wk->timeout);
 862                         continue;
 863                 }
 864
 865                 switch (wk->type) {
 866                 default:
 867                         WARN_ON(1);
 868                         /* nothing */
 869                         rma = WORK_ACT_NONE;
 870                         break;
 871                 case IEEE80211_WORK_ABORT:
 872                         rma = WORK_ACT_TIMEOUT;
 873                         break;
 874                 case IEEE80211_WORK_DIRECT_PROBE:
 875                         rma = ieee80211_direct_probe(wk);
 876                         break;
 877                 case IEEE80211_WORK_AUTH:
 878                         rma = ieee80211_authenticate(wk);
 879                         break;
 880                 case IEEE80211_WORK_ASSOC:
 881                         rma = ieee80211_associate(wk);
 882                         break;
 883                 case IEEE80211_WORK_REMAIN_ON_CHANNEL:
 884                         rma = ieee80211_remain_on_channel_timeout(wk);
 885                         break;
 886                 }
 887
 888                 wk->started = started;
 889
 890                 switch (rma) {
 891                 case WORK_ACT_NONE:
 892                         /* might have changed the timeout */
 893                         run_again(local, wk->timeout);
 894                         break;
 895                 case WORK_ACT_TIMEOUT:
 896                         list_del_rcu(&wk->list);
 897                         synchronize_rcu();
 898                         list_add(&wk->list, &free_work);
 899                         break;
 900                 default:
 901                         WARN(1, "unexpected: %d", rma);
 902                 }
 903         }
 904
 905         list_for_each_entry(wk, &local->work_list, list) {
 906                 if (!wk->started)
 907                         continue;
 908                 if (wk->chan != local->tmp_channel)
 909                         continue;
 910                 if (wk->chan_type != local->tmp_channel_type)
 911                         continue;
 912                 remain_off_channel = true;
 913         }
 914
 915         if (!remain_off_channel && local->tmp_channel) {
 916                 local->tmp_channel = NULL;
 917                 ieee80211_hw_config(local, 0);
 918                 ieee80211_offchannel_return(local, true);
 919                 /* give connection some time to breathe */
 920                 run_again(local, jiffies + HZ/2);
 921         }
 922
 923         if (list_empty(&local->work_list) && local->scan_req)
 924                 ieee80211_queue_delayed_work(&local->hw,
 925                                              &local->scan_work,
 926                                              round_jiffies_relative(0));
 927
 928         mutex_unlock(&local->work_mtx);
 929
 930         ieee80211_recalc_idle(local);
 931
 932         list_for_each_entry_safe(wk, tmp, &free_work, list) {
 933                 wk->done(wk, NULL);
 934                 list_del(&wk->list);
 935                 kfree(wk);
 936         }
 937 }
 938
 939 void ieee80211_add_work(struct ieee80211_work *wk)
 940 {
 941         struct ieee80211_local *local;
 942
 943         if (WARN_ON(!wk->chan))
 944                 return;
 945
 946         if (WARN_ON(!wk->sdata))
 947                 return;
 948
 949         if (WARN_ON(!wk->done))
 950                 return;
 951
 952         if (WARN_ON(!ieee80211_sdata_running(wk->sdata)))
 953                 return;
 954
 955         wk->started = false;
 956
 957         local = wk->sdata->local;
 958         mutex_lock(&local->work_mtx);
 959         list_add_tail(&wk->list, &local->work_list);
 960         mutex_unlock(&local->work_mtx);
 961
 962         ieee80211_queue_work(&local->hw, &local->work_work);
 963 }
 964
 965 void ieee80211_work_init(struct ieee80211_local *local)
 966 {
 967         mutex_init(&local->work_mtx);
 968         INIT_LIST_HEAD(&local->work_list);
 969         setup_timer(&local->work_timer, ieee80211_work_timer,
 970                     (unsigned long)local);
 971         INIT_WORK(&local->work_work, ieee80211_work_work);
 972         skb_queue_head_init(&local->work_skb_queue);
 973 }
 974
 975 void ieee80211_work_purge(struct ieee80211_sub_if_data *sdata)
 976 {
 977         struct ieee80211_local *local = sdata->local;
 978         struct ieee80211_work *wk;
 979
 980         mutex_lock(&local->work_mtx);
 981         list_for_each_entry(wk, &local->work_list, list) {
 982                 if (wk->sdata != sdata)
 983                         continue;
 984                 wk->type = IEEE80211_WORK_ABORT;
 985                 wk->started = true;
 986                 wk->timeout = jiffies;
 987         }
 988         mutex_unlock(&local->work_mtx);
 989
 990         /* run cleanups etc. */
 991         ieee80211_work_work(&local->work_work);
 992
 993         mutex_lock(&local->work_mtx);
 994         list_for_each_entry(wk, &local->work_list, list) {
 995                 if (wk->sdata != sdata)
 996                         continue;
 997                 WARN_ON(1);
 998                 break;
 999         }
1000         mutex_unlock(&local->work_mtx);
1001 }
1002
1003 ieee80211_rx_result ieee80211_work_rx_mgmt(struct ieee80211_sub_if_data *sdata,
1004                                            struct sk_buff *skb)
1005 {
1006         struct ieee80211_local *local = sdata->local;
1007         struct ieee80211_mgmt *mgmt;
1008         struct ieee80211_work *wk;
1009         u16 fc;
1010
1011         if (skb->len < 24)
1012                 return RX_DROP_MONITOR;
1013
1014         mgmt = (struct ieee80211_mgmt *) skb->data;
1015         fc = le16_to_cpu(mgmt->frame_control);
1016
1017         list_for_each_entry_rcu(wk, &local->work_list, list) {
1018                 if (sdata != wk->sdata)
1019                         continue;
1020                 if (compare_ether_addr(wk->filter_ta, mgmt->sa))
1021                         continue;
1022                 if (compare_ether_addr(wk->filter_ta, mgmt->bssid))
1023                         continue;
1024
1025                 switch (fc & IEEE80211_FCTL_STYPE) {
1026                 case IEEE80211_STYPE_AUTH:
1027                 case IEEE80211_STYPE_PROBE_RESP:
1028                 case IEEE80211_STYPE_ASSOC_RESP:
1029                 case IEEE80211_STYPE_REASSOC_RESP:
1030                         skb_queue_tail(&local->work_skb_queue, skb);
1031                         ieee80211_queue_work(&local->hw, &local->work_work);
1032                         return RX_QUEUED;
1033                 }
1034         }
1035
1036         return RX_CONTINUE;
1037 }
1038
1039 static enum work_done_result ieee80211_remain_done(struct ieee80211_work *wk,
1040                                                    struct sk_buff *skb)
1041 {
1042         /*
1043          * We are done serving the remain-on-channel command.
1044          */
1045         cfg80211_remain_on_channel_expired(wk->sdata->dev, (unsigned long) wk,
1046                                            wk->chan, wk->chan_type,
1047                                            GFP_KERNEL);
1048
1049         return WORK_DONE_DESTROY;
1050 }
1051
1052 int ieee80211_wk_remain_on_channel(struct ieee80211_sub_if_data *sdata,
1053                                    struct ieee80211_channel *chan,
1054                                    enum nl80211_channel_type channel_type,
1055                                    unsigned int duration, u64 *cookie)
1056 {
1057         struct ieee80211_work *wk;
1058
1059         wk = kzalloc(sizeof(*wk), GFP_KERNEL);
1060         if (!wk)
1061                 return -ENOMEM;
1062
1063         wk->type = IEEE80211_WORK_REMAIN_ON_CHANNEL;
1064         wk->chan = chan;
1065         wk->chan_type = channel_type;
1066         wk->sdata = sdata;
1067         wk->done = ieee80211_remain_done;
1068
1069         wk->remain.duration = duration;
1070
1071         *cookie = (unsigned long) wk;
1072
1073         ieee80211_add_work(wk);
1074
1075         return 0;
1076 }
1077
1078 int ieee80211_wk_cancel_remain_on_channel(struct ieee80211_sub_if_data *sdata,
1079                                           u64 cookie)
1080 {
1081         struct ieee80211_local *local = sdata->local;
1082         struct ieee80211_work *wk, *tmp;
1083         bool found = false;
1084
1085         mutex_lock(&local->work_mtx);
1086         list_for_each_entry_safe(wk, tmp, &local->work_list, list) {
1087                 if ((unsigned long) wk == cookie) {
1088                         wk->timeout = jiffies;
1089                         found = true;
1090                         break;
1091                 }
1092         }
1093         mutex_unlock(&local->work_mtx);
1094
1095         if (!found)
1096                 return -ENOENT;
1097
1098         ieee80211_queue_work(&local->hw, &local->work_work);
1099
1100         return 0;
1101 }