net/mac80211/key.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 2007-2008  Johannes Berg <johannes@sipsolutions.net>
   6  * Copyright 2013-2014  Intel Mobile Communications GmbH
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/if_ether.h>
  14 #include <linux/etherdevice.h>
  15 #include <linux/list.h>
  16 #include <linux/rcupdate.h>
  17 #include <linux/rtnetlink.h>
  18 #include <linux/slab.h>
  19 #include <linux/export.h>
  20 #include <net/mac80211.h>
  21 #include <asm/unaligned.h>
  22 #include "ieee80211_i.h"
  23 #include "driver-ops.h"
  24 #include "debugfs_key.h"
  25 #include "aes_ccm.h"
  26 #include "aes_cmac.h"
  27
  28
  29 /**
  30  * DOC: Key handling basics
  31  *
  32  * Key handling in mac80211 is done based on per-interface (sub_if_data)
  33  * keys and per-station keys. Since each station belongs to an interface,
  34  * each station key also belongs to that interface.
  35  *
  36  * Hardware acceleration is done on a best-effort basis for algorithms
  37  * that are implemented in software,  for each key the hardware is asked
  38  * to enable that key for offloading but if it cannot do that the key is
  39  * simply kept for software encryption (unless it is for an algorithm
  40  * that isn't implemented in software).
  41  * There is currently no way of knowing whether a key is handled in SW
  42  * or HW except by looking into debugfs.
  43  *
  44  * All key management is internally protected by a mutex. Within all
  45  * other parts of mac80211, key references are, just as STA structure
  46  * references, protected by RCU. Note, however, that some things are
  47  * unprotected, namely the key->sta dereferences within the hardware
  48  * acceleration functions. This means that sta_info_destroy() must
  49  * remove the key which waits for an RCU grace period.
  50  */
  51
  52 static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
  53
  54 static void assert_key_lock(struct ieee80211_local *local)
  55 {
  56         lockdep_assert_held(&local->key_mtx);
  57 }
  58
  59 static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
  60 {
  61         /*
  62          * When this count is zero, SKB resizing for allocating tailroom
  63          * for IV or MMIC is skipped. But, this check has created two race
  64          * cases in xmit path while transiting from zero count to one:
  65          *
  66          * 1. SKB resize was skipped because no key was added but just before
  67          * the xmit key is added and SW encryption kicks off.
  68          *
  69          * 2. SKB resize was skipped because all the keys were hw planted but
  70          * just before xmit one of the key is deleted and SW encryption kicks
  71          * off.
  72          *
  73          * In both the above case SW encryption will find not enough space for
  74          * tailroom and exits with WARN_ON. (See WARN_ONs at wpa.c)
  75          *
  76          * Solution has been explained at
  77          * http://mid.gmane.org/1308590980.4322.19.camel@jlt3.sipsolutions.net
  78          */
  79
  80         if (!sdata->crypto_tx_tailroom_needed_cnt++) {
  81                 /*
  82                  * Flush all XMIT packets currently using HW encryption or no
  83                  * encryption at all if the count transition is from 0 -> 1.
  84                  */
  85                 synchronize_net();
  86         }
  87 }
  88
  89 static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
  90 {
  91         struct ieee80211_sub_if_data *sdata;
  92         struct sta_info *sta;
  93         int ret;
  94
  95         might_sleep();
  96
  97         if (key->flags & KEY_FLAG_TAINTED) {
  98                 /* If we get here, it's during resume and the key is
  99                  * tainted so shouldn't be used/programmed any more.
 100                  * However, its flags may still indicate that it was
 101                  * programmed into the device (since we're in resume)
 102                  * so clear that flag now to avoid trying to remove
 103                  * it again later.
 104                  */
 105                 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 106                 return -EINVAL;
 107         }
 108
 109         if (!key->local->ops->set_key)
 110                 goto out_unsupported;
 111
 112         assert_key_lock(key->local);
 113
 114         sta = key->sta;
 115
 116         /*
 117          * If this is a per-STA GTK, check if it
 118          * is supported; if not, return.
 119          */
 120         if (sta && !(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE) &&
 121             !(key->local->hw.flags & IEEE80211_HW_SUPPORTS_PER_STA_GTK))
 122                 goto out_unsupported;
 123
 124         if (sta && !sta->uploaded)
 125                 goto out_unsupported;
 126
 127         sdata = key->sdata;
 128         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
 129                 /*
 130                  * The driver doesn't know anything about VLAN interfaces.
 131                  * Hence, don't send GTKs for VLAN interfaces to the driver.
 132                  */
 133                 if (!(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE))
 134                         goto out_unsupported;
 135         }
 136
 137         ret = drv_set_key(key->local, SET_KEY, sdata,
 138                           sta ? &sta->sta : NULL, &key->conf);
 139
 140         if (!ret) {
 141                 key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
 142
 143                 if (!(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC))
 144                         sdata->crypto_tx_tailroom_needed_cnt--;
 145
 146                 WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 147                         (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
 148
 149                 return 0;
 150         }
 151
 152         if (ret != -ENOSPC && ret != -EOPNOTSUPP)
 153                 sdata_err(sdata,
 154                           "failed to set key (%d, %pM) to hardware (%d)\n",
 155                           key->conf.keyidx,
 156                           sta ? sta->sta.addr : bcast_addr, ret);
 157
 158  out_unsupported:
 159         switch (key->conf.cipher) {
 160         case WLAN_CIPHER_SUITE_WEP40:
 161         case WLAN_CIPHER_SUITE_WEP104:
 162         case WLAN_CIPHER_SUITE_TKIP:
 163         case WLAN_CIPHER_SUITE_CCMP:
 164         case WLAN_CIPHER_SUITE_AES_CMAC:
 165                 /* all of these we can do in software */
 166                 return 0;
 167         default:
 168                 return -EINVAL;
 169         }
 170 }
 171
 172 static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
 173 {
 174         struct ieee80211_sub_if_data *sdata;
 175         struct sta_info *sta;
 176         int ret;
 177
 178         might_sleep();
 179
 180         if (!key || !key->local->ops->set_key)
 181                 return;
 182
 183         assert_key_lock(key->local);
 184
 185         if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
 186                 return;
 187
 188         sta = key->sta;
 189         sdata = key->sdata;
 190
 191         if (!(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC))
 192                 increment_tailroom_need_count(sdata);
 193
 194         ret = drv_set_key(key->local, DISABLE_KEY, sdata,
 195                           sta ? &sta->sta : NULL, &key->conf);
 196
 197         if (ret)
 198                 sdata_err(sdata,
 199                           "failed to remove key (%d, %pM) from hardware (%d)\n",
 200                           key->conf.keyidx,
 201                           sta ? sta->sta.addr : bcast_addr, ret);
 202
 203         key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 204 }
 205
 206 static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,
 207                                         int idx, bool uni, bool multi)
 208 {
 209         struct ieee80211_key *key = NULL;
 210
 211         assert_key_lock(sdata->local);
 212
 213         if (idx >= 0 && idx < NUM_DEFAULT_KEYS)
 214                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 215
 216         if (uni) {
 217                 rcu_assign_pointer(sdata->default_unicast_key, key);
 218                 drv_set_default_unicast_key(sdata->local, sdata, idx);
 219         }
 220
 221         if (multi)
 222                 rcu_assign_pointer(sdata->default_multicast_key, key);
 223
 224         ieee80211_debugfs_key_update_default(sdata);
 225 }
 226
 227 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
 228                                bool uni, bool multi)
 229 {
 230         mutex_lock(&sdata->local->key_mtx);
 231         __ieee80211_set_default_key(sdata, idx, uni, multi);
 232         mutex_unlock(&sdata->local->key_mtx);
 233 }
 234
 235 static void
 236 __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
 237 {
 238         struct ieee80211_key *key = NULL;
 239
 240         assert_key_lock(sdata->local);
 241
 242         if (idx >= NUM_DEFAULT_KEYS &&
 243             idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
 244                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 245
 246         rcu_assign_pointer(sdata->default_mgmt_key, key);
 247
 248         ieee80211_debugfs_key_update_default(sdata);
 249 }
 250
 251 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
 252                                     int idx)
 253 {
 254         mutex_lock(&sdata->local->key_mtx);
 255         __ieee80211_set_default_mgmt_key(sdata, idx);
 256         mutex_unlock(&sdata->local->key_mtx);
 257 }
 258
 259
 260 static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
 261                                   struct sta_info *sta,
 262                                   bool pairwise,
 263                                   struct ieee80211_key *old,
 264                                   struct ieee80211_key *new)
 265 {
 266         int idx;
 267         bool defunikey, defmultikey, defmgmtkey;
 268
 269         /* caller must provide at least one old/new */
 270         if (WARN_ON(!new && !old))
 271                 return;
 272
 273         if (new)
 274                 list_add_tail(&new->list, &sdata->key_list);
 275
 276         WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
 277
 278         if (old)
 279                 idx = old->conf.keyidx;
 280         else
 281                 idx = new->conf.keyidx;
 282
 283         if (sta) {
 284                 if (pairwise) {
 285                         rcu_assign_pointer(sta->ptk[idx], new);
 286                         sta->ptk_idx = idx;
 287                 } else {
 288                         rcu_assign_pointer(sta->gtk[idx], new);
 289                         sta->gtk_idx = idx;
 290                 }
 291         } else {
 292                 defunikey = old &&
 293                         old == key_mtx_dereference(sdata->local,
 294                                                 sdata->default_unicast_key);
 295                 defmultikey = old &&
 296                         old == key_mtx_dereference(sdata->local,
 297                                                 sdata->default_multicast_key);
 298                 defmgmtkey = old &&
 299                         old == key_mtx_dereference(sdata->local,
 300                                                 sdata->default_mgmt_key);
 301
 302                 if (defunikey && !new)
 303                         __ieee80211_set_default_key(sdata, -1, true, false);
 304                 if (defmultikey && !new)
 305                         __ieee80211_set_default_key(sdata, -1, false, true);
 306                 if (defmgmtkey && !new)
 307                         __ieee80211_set_default_mgmt_key(sdata, -1);
 308
 309                 rcu_assign_pointer(sdata->keys[idx], new);
 310                 if (defunikey && new)
 311                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
 312                                                     true, false);
 313                 if (defmultikey && new)
 314                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
 315                                                     false, true);
 316                 if (defmgmtkey && new)
 317                         __ieee80211_set_default_mgmt_key(sdata,
 318                                                          new->conf.keyidx);
 319         }
 320
 321         if (old)
 322                 list_del(&old->list);
 323 }
 324
 325 struct ieee80211_key *
 326 ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
 327                     const u8 *key_data,
 328                     size_t seq_len, const u8 *seq,
 329                     const struct ieee80211_cipher_scheme *cs)
 330 {
 331         struct ieee80211_key *key;
 332         int i, j, err;
 333
 334         if (WARN_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS))
 335                 return ERR_PTR(-EINVAL);
 336
 337         key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
 338         if (!key)
 339                 return ERR_PTR(-ENOMEM);
 340
 341         /*
 342          * Default to software encryption; we'll later upload the
 343          * key to the hardware if possible.
 344          */
 345         key->conf.flags = 0;
 346         key->flags = 0;
 347
 348         key->conf.cipher = cipher;
 349         key->conf.keyidx = idx;
 350         key->conf.keylen = key_len;
 351         switch (cipher) {
 352         case WLAN_CIPHER_SUITE_WEP40:
 353         case WLAN_CIPHER_SUITE_WEP104:
 354                 key->conf.iv_len = IEEE80211_WEP_IV_LEN;
 355                 key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
 356                 break;
 357         case WLAN_CIPHER_SUITE_TKIP:
 358                 key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
 359                 key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
 360                 if (seq) {
 361                         for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
 362                                 key->u.tkip.rx[i].iv32 =
 363                                         get_unaligned_le32(&seq[2]);
 364                                 key->u.tkip.rx[i].iv16 =
 365                                         get_unaligned_le16(seq);
 366                         }
 367                 }
 368                 spin_lock_init(&key->u.tkip.txlock);
 369                 break;
 370         case WLAN_CIPHER_SUITE_CCMP:
 371                 key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
 372                 key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
 373                 if (seq) {
 374                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
 375                                 for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
 376                                         key->u.ccmp.rx_pn[i][j] =
 377                                                 seq[IEEE80211_CCMP_PN_LEN - j - 1];
 378                 }
 379                 /*
 380                  * Initialize AES key state here as an optimization so that
 381                  * it does not need to be initialized for every packet.
 382                  */
 383                 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(key_data);
 384                 if (IS_ERR(key->u.ccmp.tfm)) {
 385                         err = PTR_ERR(key->u.ccmp.tfm);
 386                         kfree(key);
 387                         return ERR_PTR(err);
 388                 }
 389                 break;
 390         case WLAN_CIPHER_SUITE_AES_CMAC:
 391                 key->conf.iv_len = 0;
 392                 key->conf.icv_len = sizeof(struct ieee80211_mmie);
 393                 if (seq)
 394                         for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
 395                                 key->u.aes_cmac.rx_pn[j] =
 396                                         seq[IEEE80211_CMAC_PN_LEN - j - 1];
 397                 /*
 398                  * Initialize AES key state here as an optimization so that
 399                  * it does not need to be initialized for every packet.
 400                  */
 401                 key->u.aes_cmac.tfm =
 402                         ieee80211_aes_cmac_key_setup(key_data);
 403                 if (IS_ERR(key->u.aes_cmac.tfm)) {
 404                         err = PTR_ERR(key->u.aes_cmac.tfm);
 405                         kfree(key);
 406                         return ERR_PTR(err);
 407                 }
 408                 break;
 409         default:
 410                 if (cs) {
 411                         size_t len = (seq_len > MAX_PN_LEN) ?
 412                                                 MAX_PN_LEN : seq_len;
 413
 414                         key->conf.iv_len = cs->hdr_len;
 415                         key->conf.icv_len = cs->mic_len;
 416                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
 417                                 for (j = 0; j < len; j++)
 418                                         key->u.gen.rx_pn[i][j] =
 419                                                         seq[len - j - 1];
 420                 }
 421         }
 422         memcpy(key->conf.key, key_data, key_len);
 423         INIT_LIST_HEAD(&key->list);
 424
 425         return key;
 426 }
 427
 428 static void ieee80211_key_free_common(struct ieee80211_key *key)
 429 {
 430         if (key->conf.cipher == WLAN_CIPHER_SUITE_CCMP)
 431                 ieee80211_aes_key_free(key->u.ccmp.tfm);
 432         if (key->conf.cipher == WLAN_CIPHER_SUITE_AES_CMAC)
 433                 ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
 434         kzfree(key);
 435 }
 436
 437 static void __ieee80211_key_destroy(struct ieee80211_key *key,
 438                                     bool delay_tailroom)
 439 {
 440         if (key->local)
 441                 ieee80211_key_disable_hw_accel(key);
 442
 443         if (key->local) {
 444                 struct ieee80211_sub_if_data *sdata = key->sdata;
 445
 446                 ieee80211_debugfs_key_remove(key);
 447
 448                 if (delay_tailroom) {
 449                         /* see ieee80211_delayed_tailroom_dec */
 450                         sdata->crypto_tx_tailroom_pending_dec++;
 451                         schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
 452                                               HZ/2);
 453                 } else {
 454                         sdata->crypto_tx_tailroom_needed_cnt--;
 455                 }
 456         }
 457
 458         ieee80211_key_free_common(key);
 459 }
 460
 461 static void ieee80211_key_destroy(struct ieee80211_key *key,
 462                                   bool delay_tailroom)
 463 {
 464         if (!key)
 465                 return;
 466
 467         /*
 468          * Synchronize so the TX path can no longer be using
 469          * this key before we free/remove it.
 470          */
 471         synchronize_net();
 472
 473         __ieee80211_key_destroy(key, delay_tailroom);
 474 }
 475
 476 void ieee80211_key_free_unused(struct ieee80211_key *key)
 477 {
 478         WARN_ON(key->sdata || key->local);
 479         ieee80211_key_free_common(key);
 480 }
 481
 482 int ieee80211_key_link(struct ieee80211_key *key,
 483                        struct ieee80211_sub_if_data *sdata,
 484                        struct sta_info *sta)
 485 {
 486         struct ieee80211_local *local = sdata->local;
 487         struct ieee80211_key *old_key;
 488         int idx, ret;
 489         bool pairwise;
 490
 491         pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
 492         idx = key->conf.keyidx;
 493         key->local = sdata->local;
 494         key->sdata = sdata;
 495         key->sta = sta;
 496
 497         mutex_lock(&sdata->local->key_mtx);
 498
 499         if (sta && pairwise)
 500                 old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
 501         else if (sta)
 502                 old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);
 503         else
 504                 old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 505
 506         increment_tailroom_need_count(sdata);
 507
 508         ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
 509         ieee80211_key_destroy(old_key, true);
 510
 511         ieee80211_debugfs_key_add(key);
 512
 513         if (!local->wowlan) {
 514                 ret = ieee80211_key_enable_hw_accel(key);
 515                 if (ret)
 516                         ieee80211_key_free(key, true);
 517         } else {
 518                 ret = 0;
 519         }
 520
 521         mutex_unlock(&sdata->local->key_mtx);
 522
 523         return ret;
 524 }
 525
 526 void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
 527 {
 528         if (!key)
 529                 return;
 530
 531         /*
 532          * Replace key with nothingness if it was ever used.
 533          */
 534         if (key->sdata)
 535                 ieee80211_key_replace(key->sdata, key->sta,
 536                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 537                                 key, NULL);
 538         ieee80211_key_destroy(key, delay_tailroom);
 539 }
 540
 541 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
 542 {
 543         struct ieee80211_key *key;
 544
 545         ASSERT_RTNL();
 546
 547         if (WARN_ON(!ieee80211_sdata_running(sdata)))
 548                 return;
 549
 550         mutex_lock(&sdata->local->key_mtx);
 551
 552         sdata->crypto_tx_tailroom_needed_cnt = 0;
 553
 554         list_for_each_entry(key, &sdata->key_list, list) {
 555                 increment_tailroom_need_count(sdata);
 556                 ieee80211_key_enable_hw_accel(key);
 557         }
 558
 559         mutex_unlock(&sdata->local->key_mtx);
 560 }
 561
 562 void ieee80211_iter_keys(struct ieee80211_hw *hw,
 563                          struct ieee80211_vif *vif,
 564                          void (*iter)(struct ieee80211_hw *hw,
 565                                       struct ieee80211_vif *vif,
 566                                       struct ieee80211_sta *sta,
 567                                       struct ieee80211_key_conf *key,
 568                                       void *data),
 569                          void *iter_data)
 570 {
 571         struct ieee80211_local *local = hw_to_local(hw);
 572         struct ieee80211_key *key, *tmp;
 573         struct ieee80211_sub_if_data *sdata;
 574
 575         ASSERT_RTNL();
 576
 577         mutex_lock(&local->key_mtx);
 578         if (vif) {
 579                 sdata = vif_to_sdata(vif);
 580                 list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
 581                         iter(hw, &sdata->vif,
 582                              key->sta ? &key->sta->sta : NULL,
 583                              &key->conf, iter_data);
 584         } else {
 585                 list_for_each_entry(sdata, &local->interfaces, list)
 586                         list_for_each_entry_safe(key, tmp,
 587                                                  &sdata->key_list, list)
 588                                 iter(hw, &sdata->vif,
 589                                      key->sta ? &key->sta->sta : NULL,
 590                                      &key->conf, iter_data);
 591         }
 592         mutex_unlock(&local->key_mtx);
 593 }
 594 EXPORT_SYMBOL(ieee80211_iter_keys);
 595
 596 static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
 597                                       struct list_head *keys)
 598 {
 599         struct ieee80211_key *key, *tmp;
 600
 601         sdata->crypto_tx_tailroom_needed_cnt -=
 602                 sdata->crypto_tx_tailroom_pending_dec;
 603         sdata->crypto_tx_tailroom_pending_dec = 0;
 604
 605         ieee80211_debugfs_key_remove_mgmt_default(sdata);
 606
 607         list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
 608                 ieee80211_key_replace(key->sdata, key->sta,
 609                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 610                                 key, NULL);
 611                 list_add_tail(&key->list, keys);
 612         }
 613
 614         ieee80211_debugfs_key_update_default(sdata);
 615 }
 616
 617 void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
 618                          bool force_synchronize)
 619 {
 620         struct ieee80211_local *local = sdata->local;
 621         struct ieee80211_sub_if_data *vlan;
 622         struct ieee80211_key *key, *tmp;
 623         LIST_HEAD(keys);
 624
 625         cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
 626
 627         mutex_lock(&local->key_mtx);
 628
 629         ieee80211_free_keys_iface(sdata, &keys);
 630
 631         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 632                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 633                         ieee80211_free_keys_iface(vlan, &keys);
 634         }
 635
 636         if (!list_empty(&keys) || force_synchronize)
 637                 synchronize_net();
 638         list_for_each_entry_safe(key, tmp, &keys, list)
 639                 __ieee80211_key_destroy(key, false);
 640
 641         WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
 642                      sdata->crypto_tx_tailroom_pending_dec);
 643         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 644                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 645                         WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
 646                                      vlan->crypto_tx_tailroom_pending_dec);
 647         }
 648
 649         mutex_unlock(&local->key_mtx);
 650 }
 651
 652 void ieee80211_free_sta_keys(struct ieee80211_local *local,
 653                              struct sta_info *sta)
 654 {
 655         struct ieee80211_key *key;
 656         int i;
 657
 658         mutex_lock(&local->key_mtx);
 659         for (i = 0; i < ARRAY_SIZE(sta->gtk); i++) {
 660                 key = key_mtx_dereference(local, sta->gtk[i]);
 661                 if (!key)
 662                         continue;
 663                 ieee80211_key_replace(key->sdata, key->sta,
 664                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 665                                 key, NULL);
 666                 __ieee80211_key_destroy(key, true);
 667         }
 668
 669         for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
 670                 key = key_mtx_dereference(local, sta->ptk[i]);
 671                 if (!key)
 672                         continue;
 673                 ieee80211_key_replace(key->sdata, key->sta,
 674                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 675                                 key, NULL);
 676                 __ieee80211_key_destroy(key, true);
 677         }
 678
 679         mutex_unlock(&local->key_mtx);
 680 }
 681
 682 void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
 683 {
 684         struct ieee80211_sub_if_data *sdata;
 685
 686         sdata = container_of(wk, struct ieee80211_sub_if_data,
 687                              dec_tailroom_needed_wk.work);
 688
 689         /*
 690          * The reason for the delayed tailroom needed decrementing is to
 691          * make roaming faster: during roaming, all keys are first deleted
 692          * and then new keys are installed. The first new key causes the
 693          * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
 694          * the cost of synchronize_net() (which can be slow). Avoid this
 695          * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
 696          * key removal for a while, so if we roam the value is larger than
 697          * zero and no 0->1 transition happens.
 698          *
 699          * The cost is that if the AP switching was from an AP with keys
 700          * to one without, we still allocate tailroom while it would no
 701          * longer be needed. However, in the typical (fast) roaming case
 702          * within an ESS this usually won't happen.
 703          */
 704
 705         mutex_lock(&sdata->local->key_mtx);
 706         sdata->crypto_tx_tailroom_needed_cnt -=
 707                 sdata->crypto_tx_tailroom_pending_dec;
 708         sdata->crypto_tx_tailroom_pending_dec = 0;
 709         mutex_unlock(&sdata->local->key_mtx);
 710 }
 711
 712 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
 713                                 const u8 *replay_ctr, gfp_t gfp)
 714 {
 715         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 716
 717         trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
 718
 719         cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
 720 }
 721 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
 722
 723 void ieee80211_get_key_tx_seq(struct ieee80211_key_conf *keyconf,
 724                               struct ieee80211_key_seq *seq)
 725 {
 726         struct ieee80211_key *key;
 727         u64 pn64;
 728
 729         if (WARN_ON(!(keyconf->flags & IEEE80211_KEY_FLAG_GENERATE_IV)))
 730                 return;
 731
 732         key = container_of(keyconf, struct ieee80211_key, conf);
 733
 734         switch (key->conf.cipher) {
 735         case WLAN_CIPHER_SUITE_TKIP:
 736                 seq->tkip.iv32 = key->u.tkip.tx.iv32;
 737                 seq->tkip.iv16 = key->u.tkip.tx.iv16;
 738                 break;
 739         case WLAN_CIPHER_SUITE_CCMP:
 740                 pn64 = atomic64_read(&key->u.ccmp.tx_pn);
 741                 seq->ccmp.pn[5] = pn64;
 742                 seq->ccmp.pn[4] = pn64 >> 8;
 743                 seq->ccmp.pn[3] = pn64 >> 16;
 744                 seq->ccmp.pn[2] = pn64 >> 24;
 745                 seq->ccmp.pn[1] = pn64 >> 32;
 746                 seq->ccmp.pn[0] = pn64 >> 40;
 747                 break;
 748         case WLAN_CIPHER_SUITE_AES_CMAC:
 749                 pn64 = atomic64_read(&key->u.aes_cmac.tx_pn);
 750                 seq->ccmp.pn[5] = pn64;
 751                 seq->ccmp.pn[4] = pn64 >> 8;
 752                 seq->ccmp.pn[3] = pn64 >> 16;
 753                 seq->ccmp.pn[2] = pn64 >> 24;
 754                 seq->ccmp.pn[1] = pn64 >> 32;
 755                 seq->ccmp.pn[0] = pn64 >> 40;
 756                 break;
 757         default:
 758                 WARN_ON(1);
 759         }
 760 }
 761 EXPORT_SYMBOL(ieee80211_get_key_tx_seq);
 762
 763 void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
 764                               int tid, struct ieee80211_key_seq *seq)
 765 {
 766         struct ieee80211_key *key;
 767         const u8 *pn;
 768
 769         key = container_of(keyconf, struct ieee80211_key, conf);
 770
 771         switch (key->conf.cipher) {
 772         case WLAN_CIPHER_SUITE_TKIP:
 773                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
 774                         return;
 775                 seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
 776                 seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
 777                 break;
 778         case WLAN_CIPHER_SUITE_CCMP:
 779                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
 780                         return;
 781                 if (tid < 0)
 782                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
 783                 else
 784                         pn = key->u.ccmp.rx_pn[tid];
 785                 memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);
 786                 break;
 787         case WLAN_CIPHER_SUITE_AES_CMAC:
 788                 if (WARN_ON(tid != 0))
 789                         return;
 790                 pn = key->u.aes_cmac.rx_pn;
 791                 memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);
 792                 break;
 793         }
 794 }
 795 EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
 796
 797 void ieee80211_set_key_tx_seq(struct ieee80211_key_conf *keyconf,
 798                               struct ieee80211_key_seq *seq)
 799 {
 800         struct ieee80211_key *key;
 801         u64 pn64;
 802
 803         key = container_of(keyconf, struct ieee80211_key, conf);
 804
 805         switch (key->conf.cipher) {
 806         case WLAN_CIPHER_SUITE_TKIP:
 807                 key->u.tkip.tx.iv32 = seq->tkip.iv32;
 808                 key->u.tkip.tx.iv16 = seq->tkip.iv16;
 809                 break;
 810         case WLAN_CIPHER_SUITE_CCMP:
 811                 pn64 = (u64)seq->ccmp.pn[5] |
 812                        ((u64)seq->ccmp.pn[4] << 8) |
 813                        ((u64)seq->ccmp.pn[3] << 16) |
 814                        ((u64)seq->ccmp.pn[2] << 24) |
 815                        ((u64)seq->ccmp.pn[1] << 32) |
 816                        ((u64)seq->ccmp.pn[0] << 40);
 817                 atomic64_set(&key->u.ccmp.tx_pn, pn64);
 818                 break;
 819         case WLAN_CIPHER_SUITE_AES_CMAC:
 820                 pn64 = (u64)seq->aes_cmac.pn[5] |
 821                        ((u64)seq->aes_cmac.pn[4] << 8) |
 822                        ((u64)seq->aes_cmac.pn[3] << 16) |
 823                        ((u64)seq->aes_cmac.pn[2] << 24) |
 824                        ((u64)seq->aes_cmac.pn[1] << 32) |
 825                        ((u64)seq->aes_cmac.pn[0] << 40);
 826                 atomic64_set(&key->u.aes_cmac.tx_pn, pn64);
 827                 break;
 828         default:
 829                 WARN_ON(1);
 830                 break;
 831         }
 832 }
 833 EXPORT_SYMBOL_GPL(ieee80211_set_key_tx_seq);
 834
 835 void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
 836                               int tid, struct ieee80211_key_seq *seq)
 837 {
 838         struct ieee80211_key *key;
 839         u8 *pn;
 840
 841         key = container_of(keyconf, struct ieee80211_key, conf);
 842
 843         switch (key->conf.cipher) {
 844         case WLAN_CIPHER_SUITE_TKIP:
 845                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
 846                         return;
 847                 key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
 848                 key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
 849                 break;
 850         case WLAN_CIPHER_SUITE_CCMP:
 851                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
 852                         return;
 853                 if (tid < 0)
 854                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
 855                 else
 856                         pn = key->u.ccmp.rx_pn[tid];
 857                 memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
 858                 break;
 859         case WLAN_CIPHER_SUITE_AES_CMAC:
 860                 if (WARN_ON(tid != 0))
 861                         return;
 862                 pn = key->u.aes_cmac.rx_pn;
 863                 memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
 864                 break;
 865         default:
 866                 WARN_ON(1);
 867                 break;
 868         }
 869 }
 870 EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
 871
 872 void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
 873 {
 874         struct ieee80211_key *key;
 875
 876         key = container_of(keyconf, struct ieee80211_key, conf);
 877
 878         assert_key_lock(key->local);
 879
 880         /*
 881          * if key was uploaded, we assume the driver will/has remove(d)
 882          * it, so adjust bookkeeping accordingly
 883          */
 884         if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
 885                 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 886
 887                 if (!(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC))
 888                         increment_tailroom_need_count(key->sdata);
 889         }
 890
 891         ieee80211_key_free(key, false);
 892 }
 893 EXPORT_SYMBOL_GPL(ieee80211_remove_key);
 894
 895 struct ieee80211_key_conf *
 896 ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
 897                         struct ieee80211_key_conf *keyconf)
 898 {
 899         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 900         struct ieee80211_local *local = sdata->local;
 901         struct ieee80211_key *key;
 902         int err;
 903
 904         if (WARN_ON(!local->wowlan))
 905                 return ERR_PTR(-EINVAL);
 906
 907         if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
 908                 return ERR_PTR(-EINVAL);
 909
 910         key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
 911                                   keyconf->keylen, keyconf->key,
 912                                   0, NULL, NULL);
 913         if (IS_ERR(key))
 914                 return ERR_CAST(key);
 915
 916         if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
 917                 key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
 918
 919         err = ieee80211_key_link(key, sdata, NULL);
 920         if (err)
 921                 return ERR_PTR(err);
 922
 923         return &key->conf;
 924 }
 925 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);