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_GENERATE_IV) ||
 145                       (key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
 146                         sdata->crypto_tx_tailroom_needed_cnt--;
 147
 148                 WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 149                         (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
 150
 151                 return 0;
 152         }
 153
 154         if (ret != -ENOSPC && ret != -EOPNOTSUPP)
 155                 sdata_err(sdata,
 156                           "failed to set key (%d, %pM) to hardware (%d)\n",
 157                           key->conf.keyidx,
 158                           sta ? sta->sta.addr : bcast_addr, ret);
 159
 160  out_unsupported:
 161         switch (key->conf.cipher) {
 162         case WLAN_CIPHER_SUITE_WEP40:
 163         case WLAN_CIPHER_SUITE_WEP104:
 164         case WLAN_CIPHER_SUITE_TKIP:
 165         case WLAN_CIPHER_SUITE_CCMP:
 166         case WLAN_CIPHER_SUITE_AES_CMAC:
 167                 /* all of these we can do in software */
 168                 return 0;
 169         default:
 170                 return -EINVAL;
 171         }
 172 }
 173
 174 static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
 175 {
 176         struct ieee80211_sub_if_data *sdata;
 177         struct sta_info *sta;
 178         int ret;
 179
 180         might_sleep();
 181
 182         if (!key || !key->local->ops->set_key)
 183                 return;
 184
 185         assert_key_lock(key->local);
 186
 187         if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
 188                 return;
 189
 190         sta = key->sta;
 191         sdata = key->sdata;
 192
 193         if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
 194               (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) ||
 195               (key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
 196                 increment_tailroom_need_count(sdata);
 197
 198         ret = drv_set_key(key->local, DISABLE_KEY, sdata,
 199                           sta ? &sta->sta : NULL, &key->conf);
 200
 201         if (ret)
 202                 sdata_err(sdata,
 203                           "failed to remove key (%d, %pM) from hardware (%d)\n",
 204                           key->conf.keyidx,
 205                           sta ? sta->sta.addr : bcast_addr, ret);
 206
 207         key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 208 }
 209
 210 static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,
 211                                         int idx, bool uni, bool multi)
 212 {
 213         struct ieee80211_key *key = NULL;
 214
 215         assert_key_lock(sdata->local);
 216
 217         if (idx >= 0 && idx < NUM_DEFAULT_KEYS)
 218                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 219
 220         if (uni) {
 221                 rcu_assign_pointer(sdata->default_unicast_key, key);
 222                 drv_set_default_unicast_key(sdata->local, sdata, idx);
 223         }
 224
 225         if (multi)
 226                 rcu_assign_pointer(sdata->default_multicast_key, key);
 227
 228         ieee80211_debugfs_key_update_default(sdata);
 229 }
 230
 231 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
 232                                bool uni, bool multi)
 233 {
 234         mutex_lock(&sdata->local->key_mtx);
 235         __ieee80211_set_default_key(sdata, idx, uni, multi);
 236         mutex_unlock(&sdata->local->key_mtx);
 237 }
 238
 239 static void
 240 __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
 241 {
 242         struct ieee80211_key *key = NULL;
 243
 244         assert_key_lock(sdata->local);
 245
 246         if (idx >= NUM_DEFAULT_KEYS &&
 247             idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
 248                 key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 249
 250         rcu_assign_pointer(sdata->default_mgmt_key, key);
 251
 252         ieee80211_debugfs_key_update_default(sdata);
 253 }
 254
 255 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
 256                                     int idx)
 257 {
 258         mutex_lock(&sdata->local->key_mtx);
 259         __ieee80211_set_default_mgmt_key(sdata, idx);
 260         mutex_unlock(&sdata->local->key_mtx);
 261 }
 262
 263
 264 static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
 265                                   struct sta_info *sta,
 266                                   bool pairwise,
 267                                   struct ieee80211_key *old,
 268                                   struct ieee80211_key *new)
 269 {
 270         int idx;
 271         bool defunikey, defmultikey, defmgmtkey;
 272
 273         /* caller must provide at least one old/new */
 274         if (WARN_ON(!new && !old))
 275                 return;
 276
 277         if (new)
 278                 list_add_tail(&new->list, &sdata->key_list);
 279
 280         WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);
 281
 282         if (old)
 283                 idx = old->conf.keyidx;
 284         else
 285                 idx = new->conf.keyidx;
 286
 287         if (sta) {
 288                 if (pairwise) {
 289                         rcu_assign_pointer(sta->ptk[idx], new);
 290                         sta->ptk_idx = idx;
 291                 } else {
 292                         rcu_assign_pointer(sta->gtk[idx], new);
 293                         sta->gtk_idx = idx;
 294                 }
 295         } else {
 296                 defunikey = old &&
 297                         old == key_mtx_dereference(sdata->local,
 298                                                 sdata->default_unicast_key);
 299                 defmultikey = old &&
 300                         old == key_mtx_dereference(sdata->local,
 301                                                 sdata->default_multicast_key);
 302                 defmgmtkey = old &&
 303                         old == key_mtx_dereference(sdata->local,
 304                                                 sdata->default_mgmt_key);
 305
 306                 if (defunikey && !new)
 307                         __ieee80211_set_default_key(sdata, -1, true, false);
 308                 if (defmultikey && !new)
 309                         __ieee80211_set_default_key(sdata, -1, false, true);
 310                 if (defmgmtkey && !new)
 311                         __ieee80211_set_default_mgmt_key(sdata, -1);
 312
 313                 rcu_assign_pointer(sdata->keys[idx], new);
 314                 if (defunikey && new)
 315                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
 316                                                     true, false);
 317                 if (defmultikey && new)
 318                         __ieee80211_set_default_key(sdata, new->conf.keyidx,
 319                                                     false, true);
 320                 if (defmgmtkey && new)
 321                         __ieee80211_set_default_mgmt_key(sdata,
 322                                                          new->conf.keyidx);
 323         }
 324
 325         if (old)
 326                 list_del(&old->list);
 327 }
 328
 329 struct ieee80211_key *
 330 ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
 331                     const u8 *key_data,
 332                     size_t seq_len, const u8 *seq,
 333                     const struct ieee80211_cipher_scheme *cs)
 334 {
 335         struct ieee80211_key *key;
 336         int i, j, err;
 337
 338         if (WARN_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS))
 339                 return ERR_PTR(-EINVAL);
 340
 341         key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
 342         if (!key)
 343                 return ERR_PTR(-ENOMEM);
 344
 345         /*
 346          * Default to software encryption; we'll later upload the
 347          * key to the hardware if possible.
 348          */
 349         key->conf.flags = 0;
 350         key->flags = 0;
 351
 352         key->conf.cipher = cipher;
 353         key->conf.keyidx = idx;
 354         key->conf.keylen = key_len;
 355         switch (cipher) {
 356         case WLAN_CIPHER_SUITE_WEP40:
 357         case WLAN_CIPHER_SUITE_WEP104:
 358                 key->conf.iv_len = IEEE80211_WEP_IV_LEN;
 359                 key->conf.icv_len = IEEE80211_WEP_ICV_LEN;
 360                 break;
 361         case WLAN_CIPHER_SUITE_TKIP:
 362                 key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
 363                 key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;
 364                 if (seq) {
 365                         for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
 366                                 key->u.tkip.rx[i].iv32 =
 367                                         get_unaligned_le32(&seq[2]);
 368                                 key->u.tkip.rx[i].iv16 =
 369                                         get_unaligned_le16(seq);
 370                         }
 371                 }
 372                 spin_lock_init(&key->u.tkip.txlock);
 373                 break;
 374         case WLAN_CIPHER_SUITE_CCMP:
 375                 key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
 376                 key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;
 377                 if (seq) {
 378                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
 379                                 for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)
 380                                         key->u.ccmp.rx_pn[i][j] =
 381                                                 seq[IEEE80211_CCMP_PN_LEN - j - 1];
 382                 }
 383                 /*
 384                  * Initialize AES key state here as an optimization so that
 385                  * it does not need to be initialized for every packet.
 386                  */
 387                 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(key_data);
 388                 if (IS_ERR(key->u.ccmp.tfm)) {
 389                         err = PTR_ERR(key->u.ccmp.tfm);
 390                         kfree(key);
 391                         return ERR_PTR(err);
 392                 }
 393                 break;
 394         case WLAN_CIPHER_SUITE_AES_CMAC:
 395                 key->conf.iv_len = 0;
 396                 key->conf.icv_len = sizeof(struct ieee80211_mmie);
 397                 if (seq)
 398                         for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)
 399                                 key->u.aes_cmac.rx_pn[j] =
 400                                         seq[IEEE80211_CMAC_PN_LEN - j - 1];
 401                 /*
 402                  * Initialize AES key state here as an optimization so that
 403                  * it does not need to be initialized for every packet.
 404                  */
 405                 key->u.aes_cmac.tfm =
 406                         ieee80211_aes_cmac_key_setup(key_data);
 407                 if (IS_ERR(key->u.aes_cmac.tfm)) {
 408                         err = PTR_ERR(key->u.aes_cmac.tfm);
 409                         kfree(key);
 410                         return ERR_PTR(err);
 411                 }
 412                 break;
 413         default:
 414                 if (cs) {
 415                         size_t len = (seq_len > MAX_PN_LEN) ?
 416                                                 MAX_PN_LEN : seq_len;
 417
 418                         key->conf.iv_len = cs->hdr_len;
 419                         key->conf.icv_len = cs->mic_len;
 420                         for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
 421                                 for (j = 0; j < len; j++)
 422                                         key->u.gen.rx_pn[i][j] =
 423                                                         seq[len - j - 1];
 424                 }
 425         }
 426         memcpy(key->conf.key, key_data, key_len);
 427         INIT_LIST_HEAD(&key->list);
 428
 429         return key;
 430 }
 431
 432 static void ieee80211_key_free_common(struct ieee80211_key *key)
 433 {
 434         if (key->conf.cipher == WLAN_CIPHER_SUITE_CCMP)
 435                 ieee80211_aes_key_free(key->u.ccmp.tfm);
 436         if (key->conf.cipher == WLAN_CIPHER_SUITE_AES_CMAC)
 437                 ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
 438         kzfree(key);
 439 }
 440
 441 static void __ieee80211_key_destroy(struct ieee80211_key *key,
 442                                     bool delay_tailroom)
 443 {
 444         if (key->local)
 445                 ieee80211_key_disable_hw_accel(key);
 446
 447         if (key->local) {
 448                 struct ieee80211_sub_if_data *sdata = key->sdata;
 449
 450                 ieee80211_debugfs_key_remove(key);
 451
 452                 if (delay_tailroom) {
 453                         /* see ieee80211_delayed_tailroom_dec */
 454                         sdata->crypto_tx_tailroom_pending_dec++;
 455                         schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
 456                                               HZ/2);
 457                 } else {
 458                         sdata->crypto_tx_tailroom_needed_cnt--;
 459                 }
 460         }
 461
 462         ieee80211_key_free_common(key);
 463 }
 464
 465 static void ieee80211_key_destroy(struct ieee80211_key *key,
 466                                   bool delay_tailroom)
 467 {
 468         if (!key)
 469                 return;
 470
 471         /*
 472          * Synchronize so the TX path can no longer be using
 473          * this key before we free/remove it.
 474          */
 475         synchronize_net();
 476
 477         __ieee80211_key_destroy(key, delay_tailroom);
 478 }
 479
 480 void ieee80211_key_free_unused(struct ieee80211_key *key)
 481 {
 482         WARN_ON(key->sdata || key->local);
 483         ieee80211_key_free_common(key);
 484 }
 485
 486 int ieee80211_key_link(struct ieee80211_key *key,
 487                        struct ieee80211_sub_if_data *sdata,
 488                        struct sta_info *sta)
 489 {
 490         struct ieee80211_local *local = sdata->local;
 491         struct ieee80211_key *old_key;
 492         int idx, ret;
 493         bool pairwise;
 494
 495         pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
 496         idx = key->conf.keyidx;
 497         key->local = sdata->local;
 498         key->sdata = sdata;
 499         key->sta = sta;
 500
 501         mutex_lock(&sdata->local->key_mtx);
 502
 503         if (sta && pairwise)
 504                 old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);
 505         else if (sta)
 506                 old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);
 507         else
 508                 old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);
 509
 510         increment_tailroom_need_count(sdata);
 511
 512         ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
 513         ieee80211_key_destroy(old_key, true);
 514
 515         ieee80211_debugfs_key_add(key);
 516
 517         if (!local->wowlan) {
 518                 ret = ieee80211_key_enable_hw_accel(key);
 519                 if (ret)
 520                         ieee80211_key_free(key, true);
 521         } else {
 522                 ret = 0;
 523         }
 524
 525         mutex_unlock(&sdata->local->key_mtx);
 526
 527         return ret;
 528 }
 529
 530 void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
 531 {
 532         if (!key)
 533                 return;
 534
 535         /*
 536          * Replace key with nothingness if it was ever used.
 537          */
 538         if (key->sdata)
 539                 ieee80211_key_replace(key->sdata, key->sta,
 540                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 541                                 key, NULL);
 542         ieee80211_key_destroy(key, delay_tailroom);
 543 }
 544
 545 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
 546 {
 547         struct ieee80211_key *key;
 548
 549         ASSERT_RTNL();
 550
 551         if (WARN_ON(!ieee80211_sdata_running(sdata)))
 552                 return;
 553
 554         mutex_lock(&sdata->local->key_mtx);
 555
 556         sdata->crypto_tx_tailroom_needed_cnt = 0;
 557
 558         list_for_each_entry(key, &sdata->key_list, list) {
 559                 increment_tailroom_need_count(sdata);
 560                 ieee80211_key_enable_hw_accel(key);
 561         }
 562
 563         mutex_unlock(&sdata->local->key_mtx);
 564 }
 565
 566 void ieee80211_iter_keys(struct ieee80211_hw *hw,
 567                          struct ieee80211_vif *vif,
 568                          void (*iter)(struct ieee80211_hw *hw,
 569                                       struct ieee80211_vif *vif,
 570                                       struct ieee80211_sta *sta,
 571                                       struct ieee80211_key_conf *key,
 572                                       void *data),
 573                          void *iter_data)
 574 {
 575         struct ieee80211_local *local = hw_to_local(hw);
 576         struct ieee80211_key *key, *tmp;
 577         struct ieee80211_sub_if_data *sdata;
 578
 579         ASSERT_RTNL();
 580
 581         mutex_lock(&local->key_mtx);
 582         if (vif) {
 583                 sdata = vif_to_sdata(vif);
 584                 list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
 585                         iter(hw, &sdata->vif,
 586                              key->sta ? &key->sta->sta : NULL,
 587                              &key->conf, iter_data);
 588         } else {
 589                 list_for_each_entry(sdata, &local->interfaces, list)
 590                         list_for_each_entry_safe(key, tmp,
 591                                                  &sdata->key_list, list)
 592                                 iter(hw, &sdata->vif,
 593                                      key->sta ? &key->sta->sta : NULL,
 594                                      &key->conf, iter_data);
 595         }
 596         mutex_unlock(&local->key_mtx);
 597 }
 598 EXPORT_SYMBOL(ieee80211_iter_keys);
 599
 600 static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
 601                                       struct list_head *keys)
 602 {
 603         struct ieee80211_key *key, *tmp;
 604
 605         sdata->crypto_tx_tailroom_needed_cnt -=
 606                 sdata->crypto_tx_tailroom_pending_dec;
 607         sdata->crypto_tx_tailroom_pending_dec = 0;
 608
 609         ieee80211_debugfs_key_remove_mgmt_default(sdata);
 610
 611         list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
 612                 ieee80211_key_replace(key->sdata, key->sta,
 613                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 614                                 key, NULL);
 615                 list_add_tail(&key->list, keys);
 616         }
 617
 618         ieee80211_debugfs_key_update_default(sdata);
 619 }
 620
 621 void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
 622                          bool force_synchronize)
 623 {
 624         struct ieee80211_local *local = sdata->local;
 625         struct ieee80211_sub_if_data *vlan;
 626         struct ieee80211_key *key, *tmp;
 627         LIST_HEAD(keys);
 628
 629         cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
 630
 631         mutex_lock(&local->key_mtx);
 632
 633         ieee80211_free_keys_iface(sdata, &keys);
 634
 635         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 636                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 637                         ieee80211_free_keys_iface(vlan, &keys);
 638         }
 639
 640         if (!list_empty(&keys) || force_synchronize)
 641                 synchronize_net();
 642         list_for_each_entry_safe(key, tmp, &keys, list)
 643                 __ieee80211_key_destroy(key, false);
 644
 645         WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
 646                      sdata->crypto_tx_tailroom_pending_dec);
 647         if (sdata->vif.type == NL80211_IFTYPE_AP) {
 648                 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 649                         WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
 650                                      vlan->crypto_tx_tailroom_pending_dec);
 651         }
 652
 653         mutex_unlock(&local->key_mtx);
 654 }
 655
 656 void ieee80211_free_sta_keys(struct ieee80211_local *local,
 657                              struct sta_info *sta)
 658 {
 659         struct ieee80211_key *key;
 660         int i;
 661
 662         mutex_lock(&local->key_mtx);
 663         for (i = 0; i < ARRAY_SIZE(sta->gtk); i++) {
 664                 key = key_mtx_dereference(local, sta->gtk[i]);
 665                 if (!key)
 666                         continue;
 667                 ieee80211_key_replace(key->sdata, key->sta,
 668                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 669                                 key, NULL);
 670                 __ieee80211_key_destroy(key, true);
 671         }
 672
 673         for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
 674                 key = key_mtx_dereference(local, sta->ptk[i]);
 675                 if (!key)
 676                         continue;
 677                 ieee80211_key_replace(key->sdata, key->sta,
 678                                 key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
 679                                 key, NULL);
 680                 __ieee80211_key_destroy(key, true);
 681         }
 682
 683         mutex_unlock(&local->key_mtx);
 684 }
 685
 686 void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
 687 {
 688         struct ieee80211_sub_if_data *sdata;
 689
 690         sdata = container_of(wk, struct ieee80211_sub_if_data,
 691                              dec_tailroom_needed_wk.work);
 692
 693         /*
 694          * The reason for the delayed tailroom needed decrementing is to
 695          * make roaming faster: during roaming, all keys are first deleted
 696          * and then new keys are installed. The first new key causes the
 697          * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
 698          * the cost of synchronize_net() (which can be slow). Avoid this
 699          * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
 700          * key removal for a while, so if we roam the value is larger than
 701          * zero and no 0->1 transition happens.
 702          *
 703          * The cost is that if the AP switching was from an AP with keys
 704          * to one without, we still allocate tailroom while it would no
 705          * longer be needed. However, in the typical (fast) roaming case
 706          * within an ESS this usually won't happen.
 707          */
 708
 709         mutex_lock(&sdata->local->key_mtx);
 710         sdata->crypto_tx_tailroom_needed_cnt -=
 711                 sdata->crypto_tx_tailroom_pending_dec;
 712         sdata->crypto_tx_tailroom_pending_dec = 0;
 713         mutex_unlock(&sdata->local->key_mtx);
 714 }
 715
 716 void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
 717                                 const u8 *replay_ctr, gfp_t gfp)
 718 {
 719         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 720
 721         trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
 722
 723         cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
 724 }
 725 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);
 726
 727 void ieee80211_get_key_tx_seq(struct ieee80211_key_conf *keyconf,
 728                               struct ieee80211_key_seq *seq)
 729 {
 730         struct ieee80211_key *key;
 731         u64 pn64;
 732
 733         if (WARN_ON(!(keyconf->flags & IEEE80211_KEY_FLAG_GENERATE_IV)))
 734                 return;
 735
 736         key = container_of(keyconf, struct ieee80211_key, conf);
 737
 738         switch (key->conf.cipher) {
 739         case WLAN_CIPHER_SUITE_TKIP:
 740                 seq->tkip.iv32 = key->u.tkip.tx.iv32;
 741                 seq->tkip.iv16 = key->u.tkip.tx.iv16;
 742                 break;
 743         case WLAN_CIPHER_SUITE_CCMP:
 744                 pn64 = atomic64_read(&key->u.ccmp.tx_pn);
 745                 seq->ccmp.pn[5] = pn64;
 746                 seq->ccmp.pn[4] = pn64 >> 8;
 747                 seq->ccmp.pn[3] = pn64 >> 16;
 748                 seq->ccmp.pn[2] = pn64 >> 24;
 749                 seq->ccmp.pn[1] = pn64 >> 32;
 750                 seq->ccmp.pn[0] = pn64 >> 40;
 751                 break;
 752         case WLAN_CIPHER_SUITE_AES_CMAC:
 753                 pn64 = atomic64_read(&key->u.aes_cmac.tx_pn);
 754                 seq->ccmp.pn[5] = pn64;
 755                 seq->ccmp.pn[4] = pn64 >> 8;
 756                 seq->ccmp.pn[3] = pn64 >> 16;
 757                 seq->ccmp.pn[2] = pn64 >> 24;
 758                 seq->ccmp.pn[1] = pn64 >> 32;
 759                 seq->ccmp.pn[0] = pn64 >> 40;
 760                 break;
 761         default:
 762                 WARN_ON(1);
 763         }
 764 }
 765 EXPORT_SYMBOL(ieee80211_get_key_tx_seq);
 766
 767 void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
 768                               int tid, struct ieee80211_key_seq *seq)
 769 {
 770         struct ieee80211_key *key;
 771         const u8 *pn;
 772
 773         key = container_of(keyconf, struct ieee80211_key, conf);
 774
 775         switch (key->conf.cipher) {
 776         case WLAN_CIPHER_SUITE_TKIP:
 777                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
 778                         return;
 779                 seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
 780                 seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
 781                 break;
 782         case WLAN_CIPHER_SUITE_CCMP:
 783                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
 784                         return;
 785                 if (tid < 0)
 786                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
 787                 else
 788                         pn = key->u.ccmp.rx_pn[tid];
 789                 memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);
 790                 break;
 791         case WLAN_CIPHER_SUITE_AES_CMAC:
 792                 if (WARN_ON(tid != 0))
 793                         return;
 794                 pn = key->u.aes_cmac.rx_pn;
 795                 memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);
 796                 break;
 797         }
 798 }
 799 EXPORT_SYMBOL(ieee80211_get_key_rx_seq);
 800
 801 void ieee80211_set_key_tx_seq(struct ieee80211_key_conf *keyconf,
 802                               struct ieee80211_key_seq *seq)
 803 {
 804         struct ieee80211_key *key;
 805         u64 pn64;
 806
 807         key = container_of(keyconf, struct ieee80211_key, conf);
 808
 809         switch (key->conf.cipher) {
 810         case WLAN_CIPHER_SUITE_TKIP:
 811                 key->u.tkip.tx.iv32 = seq->tkip.iv32;
 812                 key->u.tkip.tx.iv16 = seq->tkip.iv16;
 813                 break;
 814         case WLAN_CIPHER_SUITE_CCMP:
 815                 pn64 = (u64)seq->ccmp.pn[5] |
 816                        ((u64)seq->ccmp.pn[4] << 8) |
 817                        ((u64)seq->ccmp.pn[3] << 16) |
 818                        ((u64)seq->ccmp.pn[2] << 24) |
 819                        ((u64)seq->ccmp.pn[1] << 32) |
 820                        ((u64)seq->ccmp.pn[0] << 40);
 821                 atomic64_set(&key->u.ccmp.tx_pn, pn64);
 822                 break;
 823         case WLAN_CIPHER_SUITE_AES_CMAC:
 824                 pn64 = (u64)seq->aes_cmac.pn[5] |
 825                        ((u64)seq->aes_cmac.pn[4] << 8) |
 826                        ((u64)seq->aes_cmac.pn[3] << 16) |
 827                        ((u64)seq->aes_cmac.pn[2] << 24) |
 828                        ((u64)seq->aes_cmac.pn[1] << 32) |
 829                        ((u64)seq->aes_cmac.pn[0] << 40);
 830                 atomic64_set(&key->u.aes_cmac.tx_pn, pn64);
 831                 break;
 832         default:
 833                 WARN_ON(1);
 834                 break;
 835         }
 836 }
 837 EXPORT_SYMBOL_GPL(ieee80211_set_key_tx_seq);
 838
 839 void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
 840                               int tid, struct ieee80211_key_seq *seq)
 841 {
 842         struct ieee80211_key *key;
 843         u8 *pn;
 844
 845         key = container_of(keyconf, struct ieee80211_key, conf);
 846
 847         switch (key->conf.cipher) {
 848         case WLAN_CIPHER_SUITE_TKIP:
 849                 if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
 850                         return;
 851                 key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
 852                 key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
 853                 break;
 854         case WLAN_CIPHER_SUITE_CCMP:
 855                 if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
 856                         return;
 857                 if (tid < 0)
 858                         pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
 859                 else
 860                         pn = key->u.ccmp.rx_pn[tid];
 861                 memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
 862                 break;
 863         case WLAN_CIPHER_SUITE_AES_CMAC:
 864                 if (WARN_ON(tid != 0))
 865                         return;
 866                 pn = key->u.aes_cmac.rx_pn;
 867                 memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
 868                 break;
 869         default:
 870                 WARN_ON(1);
 871                 break;
 872         }
 873 }
 874 EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
 875
 876 void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
 877 {
 878         struct ieee80211_key *key;
 879
 880         key = container_of(keyconf, struct ieee80211_key, conf);
 881
 882         assert_key_lock(key->local);
 883
 884         /*
 885          * if key was uploaded, we assume the driver will/has remove(d)
 886          * it, so adjust bookkeeping accordingly
 887          */
 888         if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
 889                 key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 890
 891                 if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
 892                       (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) ||
 893                       (key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
 894                         increment_tailroom_need_count(key->sdata);
 895         }
 896
 897         ieee80211_key_free(key, false);
 898 }
 899 EXPORT_SYMBOL_GPL(ieee80211_remove_key);
 900
 901 struct ieee80211_key_conf *
 902 ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
 903                         struct ieee80211_key_conf *keyconf)
 904 {
 905         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 906         struct ieee80211_local *local = sdata->local;
 907         struct ieee80211_key *key;
 908         int err;
 909
 910         if (WARN_ON(!local->wowlan))
 911                 return ERR_PTR(-EINVAL);
 912
 913         if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
 914                 return ERR_PTR(-EINVAL);
 915
 916         key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
 917                                   keyconf->keylen, keyconf->key,
 918                                   0, NULL, NULL);
 919         if (IS_ERR(key))
 920                 return ERR_CAST(key);
 921
 922         if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
 923                 key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
 924
 925         err = ieee80211_key_link(key, sdata, NULL);
 926         if (err)
 927                 return ERR_PTR(err);
 928
 929         return &key->conf;
 930 }
 931 EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);