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                       (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
 145                         sdata->crypto_tx_tailroom_needed_cnt--;
 146
 147                 WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 148                         (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
 149
 150                 return 0;
 151         }
 152
 153         if (ret != -ENOSPC && ret != -EOPNOTSUPP)
 154                 sdata_err(sdata,
 155                           "failed to set key (%d, %pM) to hardware (%d)\n",
 156                           key->conf.keyidx,
 157                           sta ? sta->sta.addr : bcast_addr, ret);
 158
 159  out_unsupported:
 160         switch (key->conf.cipher) {
 161         case WLAN_CIPHER_SUITE_WEP40:
 162         case WLAN_CIPHER_SUITE_WEP104:
 163         case WLAN_CIPHER_SUITE_TKIP:
 164         case WLAN_CIPHER_SUITE_CCMP:
 165         case WLAN_CIPHER_SUITE_AES_CMAC:
 166                 /* all of these we can do in software */
 167                 return 0;
 168         default:
 169                 return -EINVAL;
 170         }
 171 }
 172
 173 static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
 174 {
 175         struct ieee80211_sub_if_data *sdata;
 176         struct sta_info *sta;
 177         int ret;
 178
 179         might_sleep();
 180
 181         if (!key || !key->local->ops->set_key)
 182                 return;
 183
 184         assert_key_lock(key->local);
 185
 186         if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
 187                 return;
 188
 189         sta = key->sta;
 190         sdata = key->sdata;
 191
 192         if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
 193               (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
 194                 increment_tailroom_need_count(sdata);
 195
 196         ret = drv_set_key(key->local, DISABLE_KEY, sdata,
 197                           sta ? &sta->sta : NULL, &key->conf);
 198
 199         if (ret)
 200                 sdata_err(sdata,
 201                           "failed to remove key (%d, %pM) from hardware (%d)\n",
 202                           key->conf.keyidx,
 203                           sta ? sta->sta.addr : bcast_addr, ret);
 204
 205         key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 206 }
 207
 208 static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,
 209                                         int idx, bool uni, bool multi)
 210 {
 211         struct ieee80211_key *key = NULL;
 212
 213         assert_key_lock(sdata->local);
 214
 215         if (idx >= 0 && idx < NUM_DEFAULT_KEYS)
 216                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 217
 218         if (uni) {
 219                 rcu_assign_pointer(sdata->default_unicast_key, key);
 220                 drv_set_default_unicast_key(sdata->local, sdata, idx);
 221         }
 222
 223         if (multi)
 224                 rcu_assign_pointer(sdata->default_multicast_key, key);
 225
 226         ieee80211_debugfs_key_update_default(sdata);
 227 }
 228
 229 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
 230                                bool uni, bool multi)
 231 {
 232         mutex_lock(&sdata->local->key_mtx);
 233         __ieee80211_set_default_key(sdata, idx, uni, multi);
 234         mutex_unlock(&sdata->local->key_mtx);
 235 }
 236
 237 static void
 238 __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
 239 {
 240         struct ieee80211_key *key = NULL;
 241
 242         assert_key_lock(sdata->local);
 243
 244         if (idx >= NUM_DEFAULT_KEYS &&
 245             idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
 246                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 247
 248         rcu_assign_pointer(sdata->default_mgmt_key, key);
 249
 250         ieee80211_debugfs_key_update_default(sdata);
 251 }
 252
 253 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
 254                                     int idx)
 255 {
 256         mutex_lock(&sdata->local->key_mtx);
 257         __ieee80211_set_default_mgmt_key(sdata, idx);
 258         mutex_unlock(&sdata->local->key_mtx);
 259 }
 260
 261
 262 static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
 263                                   struct sta_info *sta,
 264                                   bool pairwise,
 265                                   struct ieee80211_key *old,
 266                                   struct ieee80211_key *new)
 267 {
 268         int idx;
 269         bool defunikey, defmultikey, defmgmtkey;
 270
 271         /* caller must provide at least one old/new */
 272         if (WARN_ON(!new && !old))
 273                 return;
 274
 275         if (new)
 276                 list_add_tail(&new->list, &sdata->key_list);
 277
 278         WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
 279
 280         if (old)
 281                 idx = old->conf.keyidx;
 282         else
 283                 idx = new->conf.keyidx;
 284
 285         if (sta) {
 286                 if (pairwise) {
 287                         rcu_assign_pointer(sta->ptk[idx], new);
 288                         sta->ptk_idx = idx;
 289                 } else {
 290                         rcu_assign_pointer(sta->gtk[idx], new);
 291                         sta->gtk_idx = idx;
 292                 }
 293         } else {
 294                 defunikey = old &&
 295                         old == key_mtx_dereference(sdata->local,
 296                                                 sdata->default_unicast_key);
 297                 defmultikey = old &&
 298                         old == key_mtx_dereference(sdata->local,
 299                                                 sdata->default_multicast_key);
 300                 defmgmtkey = old &&
 301                         old == key_mtx_dereference(sdata->local,
 302                                                 sdata->default_mgmt_key);
 303
 304                 if (defunikey && !new)
 305                         __ieee80211_set_default_key(sdata, -1, true, false);
 306                 if (defmultikey && !new)
 307                         __ieee80211_set_default_key(sdata, -1, false, true);
 308                 if (defmgmtkey && !new)
 309                         __ieee80211_set_default_mgmt_key(sdata, -1);
 310
 311                 rcu_assign_pointer(sdata->keys[idx], new);
 312                 if (defunikey && new)
 313                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
 314                                                     true, false);
 315                 if (defmultikey && new)
 316                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
 317                                                     false, true);
 318                 if (defmgmtkey && new)
 319                         __ieee80211_set_default_mgmt_key(sdata,
 320                                                          new->conf.keyidx);
 321         }
 322
 323         if (old)
 324                 list_del(&old->list);
 325 }
 326
 327 struct ieee80211_key *
 328 ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
 329                     const u8 *key_data,
 330                     size_t seq_len, const u8 *seq,
 331                     const struct ieee80211_cipher_scheme *cs)
 332 {
 333         struct ieee80211_key *key;
 334         int i, j, err;
 335
 336         if (WARN_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS))
 337                 return ERR_PTR(-EINVAL);
 338
 339         key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
 340         if (!key)
 341                 return ERR_PTR(-ENOMEM);
 342
 343         /*
 344          * Default to software encryption; we'll later upload the
 345          * key to the hardware if possible.
 346          */
 347         key->conf.flags = 0;
 348         key->flags = 0;
 349
 350         key->conf.cipher = cipher;
 351         key->conf.keyidx = idx;
 352         key->conf.keylen = key_len;
 353         switch (cipher) {
 354         case WLAN_CIPHER_SUITE_WEP40:
 355         case WLAN_CIPHER_SUITE_WEP104:
 356                 key->conf.iv_len = IEEE80211_WEP_IV_LEN;
 357                 key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
 358                 break;
 359         case WLAN_CIPHER_SUITE_TKIP:
 360                 key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
 361                 key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
 362                 if (seq) {
 363                         for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
 364                                 key->u.tkip.rx[i].iv32 =
 365                                         get_unaligned_le32(&seq[2]);
 366                                 key->u.tkip.rx[i].iv16 =
 367                                         get_unaligned_le16(seq);
 368                         }
 369                 }
 370                 spin_lock_init(&key->u.tkip.txlock);
 371                 break;
 372         case WLAN_CIPHER_SUITE_CCMP:
 373                 key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
 374                 key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
 375                 if (seq) {
 376                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
 377                                 for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
 378                                         key->u.ccmp.rx_pn[i][j] =
 379                                                 seq[IEEE80211_CCMP_PN_LEN - j - 1];
 380                 }
 381                 /*
 382                  * Initialize AES key state here as an optimization so that
 383                  * it does not need to be initialized for every packet.
 384                  */
 385                 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(key_data);
 386                 if (IS_ERR(key->u.ccmp.tfm)) {
 387                         err = PTR_ERR(key->u.ccmp.tfm);
 388                         kfree(key);
 389                         return ERR_PTR(err);
 390                 }
 391                 break;
 392         case WLAN_CIPHER_SUITE_AES_CMAC:
 393                 key->conf.iv_len = 0;
 394                 key->conf.icv_len = sizeof(struct ieee80211_mmie);
 395                 if (seq)
 396                         for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
 397                                 key->u.aes_cmac.rx_pn[j] =
 398                                         seq[IEEE80211_CMAC_PN_LEN - j - 1];
 399                 /*
 400                  * Initialize AES key state here as an optimization so that
 401                  * it does not need to be initialized for every packet.
 402                  */
 403                 key->u.aes_cmac.tfm =
 404                         ieee80211_aes_cmac_key_setup(key_data);
 405                 if (IS_ERR(key->u.aes_cmac.tfm)) {
 406                         err = PTR_ERR(key->u.aes_cmac.tfm);
 407                         kfree(key);
 408                         return ERR_PTR(err);
 409                 }
 410                 break;
 411         default:
 412                 if (cs) {
 413                         size_t len = (seq_len > MAX_PN_LEN) ?
 414                                                 MAX_PN_LEN : seq_len;
 415
 416                         key->conf.iv_len = cs->hdr_len;
 417                         key->conf.icv_len = cs->mic_len;
 418                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
 419                                 for (j = 0; j < len; j++)
 420                                         key->u.gen.rx_pn[i][j] =
 421                                                         seq[len - j - 1];
 422                 }
 423         }
 424         memcpy(key->conf.key, key_data, key_len);
 425         INIT_LIST_HEAD(&key->list);
 426
 427         return key;
 428 }
 429
 430 static void ieee80211_key_free_common(struct ieee80211_key *key)
 431 {
 432         if (key->conf.cipher == WLAN_CIPHER_SUITE_CCMP)
 433                 ieee80211_aes_key_free(key->u.ccmp.tfm);
 434         if (key->conf.cipher == WLAN_CIPHER_SUITE_AES_CMAC)
 435                 ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
 436         kzfree(key);
 437 }
 438
 439 static void __ieee80211_key_destroy(struct ieee80211_key *key,
 440                                     bool delay_tailroom)
 441 {
 442         if (key->local)
 443                 ieee80211_key_disable_hw_accel(key);
 444
 445         if (key->local) {
 446                 struct ieee80211_sub_if_data *sdata = key->sdata;
 447
 448                 ieee80211_debugfs_key_remove(key);
 449
 450                 if (delay_tailroom) {
 451                         /* see ieee80211_delayed_tailroom_dec */
 452                         sdata->crypto_tx_tailroom_pending_dec++;
 453                         schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
 454                                               HZ/2);
 455                 } else {
 456                         sdata->crypto_tx_tailroom_needed_cnt--;
 457                 }
 458         }
 459
 460         ieee80211_key_free_common(key);
 461 }
 462
 463 static void ieee80211_key_destroy(struct ieee80211_key *key,
 464                                   bool delay_tailroom)
 465 {
 466         if (!key)
 467                 return;
 468
 469         /*
 470          * Synchronize so the TX path can no longer be using
 471          * this key before we free/remove it.
 472          */
 473         synchronize_net();
 474
 475         __ieee80211_key_destroy(key, delay_tailroom);
 476 }
 477
 478 void ieee80211_key_free_unused(struct ieee80211_key *key)
 479 {
 480         WARN_ON(key->sdata || key->local);
 481         ieee80211_key_free_common(key);
 482 }
 483
 484 int ieee80211_key_link(struct ieee80211_key *key,
 485                        struct ieee80211_sub_if_data *sdata,
 486                        struct sta_info *sta)
 487 {
 488         struct ieee80211_local *local = sdata->local;
 489         struct ieee80211_key *old_key;
 490         int idx, ret;
 491         bool pairwise;
 492
 493         pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
 494         idx = key->conf.keyidx;
 495         key->local = sdata->local;
 496         key->sdata = sdata;
 497         key->sta = sta;
 498
 499         mutex_lock(&sdata->local->key_mtx);
 500
 501         if (sta && pairwise)
 502                 old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
 503         else if (sta)
 504                 old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);
 505         else
 506                 old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 507
 508         increment_tailroom_need_count(sdata);
 509
 510         ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
 511         ieee80211_key_destroy(old_key, true);
 512
 513         ieee80211_debugfs_key_add(key);
 514
 515         if (!local->wowlan) {
 516                 ret = ieee80211_key_enable_hw_accel(key);
 517                 if (ret)
 518                         ieee80211_key_free(key, true);
 519         } else {
 520                 ret = 0;
 521         }
 522
 523         mutex_unlock(&sdata->local->key_mtx);
 524
 525         return ret;
 526 }
 527
 528 void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
 529 {
 530         if (!key)
 531                 return;
 532
 533         /*
 534          * Replace key with nothingness if it was ever used.
 535          */
 536         if (key->sdata)
 537                 ieee80211_key_replace(key->sdata, key->sta,
 538                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 539                                 key, NULL);
 540         ieee80211_key_destroy(key, delay_tailroom);
 541 }
 542
 543 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
 544 {
 545         struct ieee80211_key *key;
 546
 547         ASSERT_RTNL();
 548
 549         if (WARN_ON(!ieee80211_sdata_running(sdata)))
 550                 return;
 551
 552         mutex_lock(&sdata->local->key_mtx);
 553
 554         sdata->crypto_tx_tailroom_needed_cnt = 0;
 555
 556         list_for_each_entry(key, &sdata->key_list, list) {
 557                 increment_tailroom_need_count(sdata);
 558                 ieee80211_key_enable_hw_accel(key);
 559         }
 560
 561         mutex_unlock(&sdata->local->key_mtx);
 562 }
 563
 564 void ieee80211_iter_keys(struct ieee80211_hw *hw,
 565                          struct ieee80211_vif *vif,
 566                          void (*iter)(struct ieee80211_hw *hw,
 567                                       struct ieee80211_vif *vif,
 568                                       struct ieee80211_sta *sta,
 569                                       struct ieee80211_key_conf *key,
 570                                       void *data),
 571                          void *iter_data)
 572 {
 573         struct ieee80211_local *local = hw_to_local(hw);
 574         struct ieee80211_key *key, *tmp;
 575         struct ieee80211_sub_if_data *sdata;
 576
 577         ASSERT_RTNL();
 578
 579         mutex_lock(&local->key_mtx);
 580         if (vif) {
 581                 sdata = vif_to_sdata(vif);
 582                 list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
 583                         iter(hw, &sdata->vif,
 584                              key->sta ? &key->sta->sta : NULL,
 585                              &key->conf, iter_data);
 586         } else {
 587                 list_for_each_entry(sdata, &local->interfaces, list)
 588                         list_for_each_entry_safe(key, tmp,
 589                                                  &sdata->key_list, list)
 590                                 iter(hw, &sdata->vif,
 591                                      key->sta ? &key->sta->sta : NULL,
 592                                      &key->conf, iter_data);
 593         }
 594         mutex_unlock(&local->key_mtx);
 595 }
 596 EXPORT_SYMBOL(ieee80211_iter_keys);
 597
 598 static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
 599                                       struct list_head *keys)
 600 {
 601         struct ieee80211_key *key, *tmp;
 602
 603         sdata->crypto_tx_tailroom_needed_cnt -=
 604                 sdata->crypto_tx_tailroom_pending_dec;
 605         sdata->crypto_tx_tailroom_pending_dec = 0;
 606
 607         ieee80211_debugfs_key_remove_mgmt_default(sdata);
 608
 609         list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
 610                 ieee80211_key_replace(key->sdata, key->sta,
 611                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 612                                 key, NULL);
 613                 list_add_tail(&key->list, keys);
 614         }
 615
 616         ieee80211_debugfs_key_update_default(sdata);
 617 }
 618
 619 void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
 620                          bool force_synchronize)
 621 {
 622         struct ieee80211_local *local = sdata->local;
 623         struct ieee80211_sub_if_data *vlan;
 624         struct ieee80211_key *key, *tmp;
 625         LIST_HEAD(keys);
 626
 627         cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
 628
 629         mutex_lock(&local->key_mtx);
 630
 631         ieee80211_free_keys_iface(sdata, &keys);
 632
 633         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 634                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 635                         ieee80211_free_keys_iface(vlan, &keys);
 636         }
 637
 638         if (!list_empty(&keys) || force_synchronize)
 639                 synchronize_net();
 640         list_for_each_entry_safe(key, tmp, &keys, list)
 641                 __ieee80211_key_destroy(key, false);
 642
 643         WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
 644                      sdata->crypto_tx_tailroom_pending_dec);
 645         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 646                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 647                         WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
 648                                      vlan->crypto_tx_tailroom_pending_dec);
 649         }
 650
 651         mutex_unlock(&local->key_mtx);
 652 }
 653
 654 void ieee80211_free_sta_keys(struct ieee80211_local *local,
 655                              struct sta_info *sta)
 656 {
 657         struct ieee80211_key *key;
 658         int i;
 659
 660         mutex_lock(&local->key_mtx);
 661         for (i = 0; i < ARRAY_SIZE(sta->gtk); i++) {
 662                 key = key_mtx_dereference(local, sta->gtk[i]);
 663                 if (!key)
 664                         continue;
 665                 ieee80211_key_replace(key->sdata, key->sta,
 666                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 667                                 key, NULL);
 668                 __ieee80211_key_destroy(key, true);
 669         }
 670
 671         for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
 672                 key = key_mtx_dereference(local, sta->ptk[i]);
 673                 if (!key)
 674                         continue;
 675                 ieee80211_key_replace(key->sdata, key->sta,
 676                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 677                                 key, NULL);
 678                 __ieee80211_key_destroy(key, true);
 679         }
 680
 681         mutex_unlock(&local->key_mtx);
 682 }
 683
 684 void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
 685 {
 686         struct ieee80211_sub_if_data *sdata;
 687
 688         sdata = container_of(wk, struct ieee80211_sub_if_data,
 689                              dec_tailroom_needed_wk.work);
 690
 691         /*
 692          * The reason for the delayed tailroom needed decrementing is to
 693          * make roaming faster: during roaming, all keys are first deleted
 694          * and then new keys are installed. The first new key causes the
 695          * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
 696          * the cost of synchronize_net() (which can be slow). Avoid this
 697          * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
 698          * key removal for a while, so if we roam the value is larger than
 699          * zero and no 0->1 transition happens.
 700          *
 701          * The cost is that if the AP switching was from an AP with keys
 702          * to one without, we still allocate tailroom while it would no
 703          * longer be needed. However, in the typical (fast) roaming case
 704          * within an ESS this usually won't happen.
 705          */
 706
 707         mutex_lock(&sdata->local->key_mtx);
 708         sdata->crypto_tx_tailroom_needed_cnt -=
 709                 sdata->crypto_tx_tailroom_pending_dec;
 710         sdata->crypto_tx_tailroom_pending_dec = 0;
 711         mutex_unlock(&sdata->local->key_mtx);
 712 }
 713
 714 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
 715                                 const u8 *replay_ctr, gfp_t gfp)
 716 {
 717         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 718
 719         trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
 720
 721         cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
 722 }
 723 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
 724
 725 void ieee80211_get_key_tx_seq(struct ieee80211_key_conf *keyconf,
 726                               struct ieee80211_key_seq *seq)
 727 {
 728         struct ieee80211_key *key;
 729         u64 pn64;
 730
 731         if (WARN_ON(!(keyconf->flags & IEEE80211_KEY_FLAG_GENERATE_IV)))
 732                 return;
 733
 734         key = container_of(keyconf, struct ieee80211_key, conf);
 735
 736         switch (key->conf.cipher) {
 737         case WLAN_CIPHER_SUITE_TKIP:
 738                 seq->tkip.iv32 = key->u.tkip.tx.iv32;
 739                 seq->tkip.iv16 = key->u.tkip.tx.iv16;
 740                 break;
 741         case WLAN_CIPHER_SUITE_CCMP:
 742                 pn64 = atomic64_read(&key->u.ccmp.tx_pn);
 743                 seq->ccmp.pn[5] = pn64;
 744                 seq->ccmp.pn[4] = pn64 >> 8;
 745                 seq->ccmp.pn[3] = pn64 >> 16;
 746                 seq->ccmp.pn[2] = pn64 >> 24;
 747                 seq->ccmp.pn[1] = pn64 >> 32;
 748                 seq->ccmp.pn[0] = pn64 >> 40;
 749                 break;
 750         case WLAN_CIPHER_SUITE_AES_CMAC:
 751                 pn64 = atomic64_read(&key->u.aes_cmac.tx_pn);
 752                 seq->ccmp.pn[5] = pn64;
 753                 seq->ccmp.pn[4] = pn64 >> 8;
 754                 seq->ccmp.pn[3] = pn64 >> 16;
 755                 seq->ccmp.pn[2] = pn64 >> 24;
 756                 seq->ccmp.pn[1] = pn64 >> 32;
 757                 seq->ccmp.pn[0] = pn64 >> 40;
 758                 break;
 759         default:
 760                 WARN_ON(1);
 761         }
 762 }
 763 EXPORT_SYMBOL(ieee80211_get_key_tx_seq);
 764
 765 void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
 766                               int tid, struct ieee80211_key_seq *seq)
 767 {
 768         struct ieee80211_key *key;
 769         const u8 *pn;
 770
 771         key = container_of(keyconf, struct ieee80211_key, conf);
 772
 773         switch (key->conf.cipher) {
 774         case WLAN_CIPHER_SUITE_TKIP:
 775                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
 776                         return;
 777                 seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
 778                 seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
 779                 break;
 780         case WLAN_CIPHER_SUITE_CCMP:
 781                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
 782                         return;
 783                 if (tid < 0)
 784                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
 785                 else
 786                         pn = key->u.ccmp.rx_pn[tid];
 787                 memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);
 788                 break;
 789         case WLAN_CIPHER_SUITE_AES_CMAC:
 790                 if (WARN_ON(tid != 0))
 791                         return;
 792                 pn = key->u.aes_cmac.rx_pn;
 793                 memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);
 794                 break;
 795         }
 796 }
 797 EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
 798
 799 void ieee80211_set_key_tx_seq(struct ieee80211_key_conf *keyconf,
 800                               struct ieee80211_key_seq *seq)
 801 {
 802         struct ieee80211_key *key;
 803         u64 pn64;
 804
 805         key = container_of(keyconf, struct ieee80211_key, conf);
 806
 807         switch (key->conf.cipher) {
 808         case WLAN_CIPHER_SUITE_TKIP:
 809                 key->u.tkip.tx.iv32 = seq->tkip.iv32;
 810                 key->u.tkip.tx.iv16 = seq->tkip.iv16;
 811                 break;
 812         case WLAN_CIPHER_SUITE_CCMP:
 813                 pn64 = (u64)seq->ccmp.pn[5] |
 814                        ((u64)seq->ccmp.pn[4] << 8) |
 815                        ((u64)seq->ccmp.pn[3] << 16) |
 816                        ((u64)seq->ccmp.pn[2] << 24) |
 817                        ((u64)seq->ccmp.pn[1] << 32) |
 818                        ((u64)seq->ccmp.pn[0] << 40);
 819                 atomic64_set(&key->u.ccmp.tx_pn, pn64);
 820                 break;
 821         case WLAN_CIPHER_SUITE_AES_CMAC:
 822                 pn64 = (u64)seq->aes_cmac.pn[5] |
 823                        ((u64)seq->aes_cmac.pn[4] << 8) |
 824                        ((u64)seq->aes_cmac.pn[3] << 16) |
 825                        ((u64)seq->aes_cmac.pn[2] << 24) |
 826                        ((u64)seq->aes_cmac.pn[1] << 32) |
 827                        ((u64)seq->aes_cmac.pn[0] << 40);
 828                 atomic64_set(&key->u.aes_cmac.tx_pn, pn64);
 829                 break;
 830         default:
 831                 WARN_ON(1);
 832                 break;
 833         }
 834 }
 835 EXPORT_SYMBOL_GPL(ieee80211_set_key_tx_seq);
 836
 837 void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
 838                               int tid, struct ieee80211_key_seq *seq)
 839 {
 840         struct ieee80211_key *key;
 841         u8 *pn;
 842
 843         key = container_of(keyconf, struct ieee80211_key, conf);
 844
 845         switch (key->conf.cipher) {
 846         case WLAN_CIPHER_SUITE_TKIP:
 847                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
 848                         return;
 849                 key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
 850                 key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
 851                 break;
 852         case WLAN_CIPHER_SUITE_CCMP:
 853                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
 854                         return;
 855                 if (tid < 0)
 856                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
 857                 else
 858                         pn = key->u.ccmp.rx_pn[tid];
 859                 memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
 860                 break;
 861         case WLAN_CIPHER_SUITE_AES_CMAC:
 862                 if (WARN_ON(tid != 0))
 863                         return;
 864                 pn = key->u.aes_cmac.rx_pn;
 865                 memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
 866                 break;
 867         default:
 868                 WARN_ON(1);
 869                 break;
 870         }
 871 }
 872 EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
 873
 874 void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
 875 {
 876         struct ieee80211_key *key;
 877
 878         key = container_of(keyconf, struct ieee80211_key, conf);
 879
 880         assert_key_lock(key->local);
 881
 882         /*
 883          * if key was uploaded, we assume the driver will/has remove(d)
 884          * it, so adjust bookkeeping accordingly
 885          */
 886         if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
 887                 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 888
 889                 if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
 890                       (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
 891                         increment_tailroom_need_count(key->sdata);
 892         }
 893
 894         ieee80211_key_free(key, false);
 895 }
 896 EXPORT_SYMBOL_GPL(ieee80211_remove_key);
 897
 898 struct ieee80211_key_conf *
 899 ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
 900                         struct ieee80211_key_conf *keyconf)
 901 {
 902         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 903         struct ieee80211_local *local = sdata->local;
 904         struct ieee80211_key *key;
 905         int err;
 906
 907         if (WARN_ON(!local->wowlan))
 908                 return ERR_PTR(-EINVAL);
 909
 910         if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
 911                 return ERR_PTR(-EINVAL);
 912
 913         key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
 914                                   keyconf->keylen, keyconf->key,
 915                                   0, NULL, NULL);
 916         if (IS_ERR(key))
 917                 return ERR_CAST(key);
 918
 919         if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
 920                 key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
 921
 922         err = ieee80211_key_link(key, sdata, NULL);
 923         if (err)
 924                 return ERR_PTR(err);
 925
 926         return &key->conf;
 927 }
 928 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);