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