// SPDX-License-Identifier: GPL-2.0-only

  /*
   * Copyright 2002-2005, Instant802 Networks, Inc.
   * Copyright 2005-2006, Devicescape Software, Inc.
   * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>

   * Copyright 2007-2008	Johannes Berg <johannes@sipsolutions.net>

   * Copyright 2013-2014  Intel Mobile Communications GmbH

   * Copyright 2015-2017	Intel Deutschland GmbH

   * Copyright 2018-2019  Intel Corporation

   */

  #include <linux/if_ether.h>
  #include <linux/etherdevice.h>
  #include <linux/list.h>

  #include <linux/rcupdate.h>

  #include <linux/rtnetlink.h>

  #include <linux/slab.h>

  #include <linux/export.h>

  #include <net/mac80211.h>

  #include <crypto/algapi.h>

  #include <asm/unaligned.h>

  #include "ieee80211_i.h"

  #include "driver-ops.h"

  #include "debugfs_key.h"
  #include "aes_ccm.h"

  #include "aes_cmac.h"

  #include "aes_gmac.h"

  #include "aes_gcm.h"

  /**
   * DOC: Key handling basics

   *
   * Key handling in mac80211 is done based on per-interface (sub_if_data)
   * keys and per-station keys. Since each station belongs to an interface,
   * each station key also belongs to that interface.
   *

   * Hardware acceleration is done on a best-effort basis for algorithms
   * that are implemented in software,  for each key the hardware is asked
   * to enable that key for offloading but if it cannot do that the key is
   * simply kept for software encryption (unless it is for an algorithm
   * that isn't implemented in software).
   * There is currently no way of knowing whether a key is handled in SW
   * or HW except by looking into debugfs.

   *

   * All key management is internally protected by a mutex. Within all
   * other parts of mac80211, key references are, just as STA structure
   * references, protected by RCU. Note, however, that some things are
   * unprotected, namely the key->sta dereferences within the hardware
   * acceleration functions. This means that sta_info_destroy() must
   * remove the key which waits for an RCU grace period.

   */
  
  static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };

  static void assert_key_lock(struct ieee80211_local *local)

  {

  	lockdep_assert_held(&local->key_mtx);

  }

  static void
  update_vlan_tailroom_need_count(struct ieee80211_sub_if_data *sdata, int delta)
  {
  	struct ieee80211_sub_if_data *vlan;
  
  	if (sdata->vif.type != NL80211_IFTYPE_AP)
  		return;

  	/* crypto_tx_tailroom_needed_cnt is protected by this */
  	assert_key_lock(sdata->local);

  	rcu_read_lock();
  
  	list_for_each_entry_rcu(vlan, &sdata->u.ap.vlans, u.vlan.list)

  		vlan->crypto_tx_tailroom_needed_cnt += delta;

  	rcu_read_unlock();

  }

  static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
  {
  	/*
  	 * When this count is zero, SKB resizing for allocating tailroom
  	 * for IV or MMIC is skipped. But, this check has created two race
  	 * cases in xmit path while transiting from zero count to one:
  	 *
  	 * 1. SKB resize was skipped because no key was added but just before
  	 * the xmit key is added and SW encryption kicks off.
  	 *
  	 * 2. SKB resize was skipped because all the keys were hw planted but
  	 * just before xmit one of the key is deleted and SW encryption kicks
  	 * off.
  	 *
  	 * In both the above case SW encryption will find not enough space for
  	 * tailroom and exits with WARN_ON. (See WARN_ONs at wpa.c)
  	 *
  	 * Solution has been explained at
  	 * http://mid.gmane.org/1308590980.4322.19.camel@jlt3.sipsolutions.net
  	 */

  	assert_key_lock(sdata->local);

  	update_vlan_tailroom_need_count(sdata, 1);

  	if (!sdata->crypto_tx_tailroom_needed_cnt++) {
  		/*
  		 * Flush all XMIT packets currently using HW encryption or no
  		 * encryption at all if the count transition is from 0 -> 1.
  		 */
  		synchronize_net();
  	}
  }

  static void decrease_tailroom_need_count(struct ieee80211_sub_if_data *sdata,
  					 int delta)
  {

  	assert_key_lock(sdata->local);

  	WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt < delta);
  
  	update_vlan_tailroom_need_count(sdata, -delta);
  	sdata->crypto_tx_tailroom_needed_cnt -= delta;
  }

  static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)

  {

  	struct ieee80211_sub_if_data *sdata = key->sdata;

  	struct sta_info *sta;

  	int ret = -EOPNOTSUPP;

  	might_sleep();

  	if (key->flags & KEY_FLAG_TAINTED) {
  		/* If we get here, it's during resume and the key is
  		 * tainted so shouldn't be used/programmed any more.
  		 * However, its flags may still indicate that it was
  		 * programmed into the device (since we're in resume)
  		 * so clear that flag now to avoid trying to remove
  		 * it again later.
  		 */

  		if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE &&
  		    !(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
  					 IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
  					 IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
  			increment_tailroom_need_count(sdata);

  		key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;

  		return -EINVAL;

  	}

  	if (!key->local->ops->set_key)

  		goto out_unsupported;

  	assert_key_lock(key->local);

  	sta = key->sta;

  	/*
  	 * If this is a per-STA GTK, check if it
  	 * is supported; if not, return.
  	 */
  	if (sta && !(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE) &&

  	    !ieee80211_hw_check(&key->local->hw, SUPPORTS_PER_STA_GTK))

  		goto out_unsupported;

  	if (sta && !sta->uploaded)
  		goto out_unsupported;

  	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
  		/*
  		 * The driver doesn't know anything about VLAN interfaces.
  		 * Hence, don't send GTKs for VLAN interfaces to the driver.
  		 */

  		if (!(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
  			ret = 1;

  			goto out_unsupported;

  		}

  	}

  	ret = drv_set_key(key->local, SET_KEY, sdata,
  			  sta ? &sta->sta : NULL, &key->conf);

  	if (!ret) {

  		key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;

  		if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
  					 IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
  					 IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))

  			decrease_tailroom_need_count(sdata, 1);

  		WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
  			(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));

  		WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_MIC_SPACE) &&
  			(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC));

  		return 0;
  	}

  	if (ret != -ENOSPC && ret != -EOPNOTSUPP && ret != 1)

  		sdata_err(sdata,

  			  "failed to set key (%d, %pM) to hardware (%d)
  ",

  			  key->conf.keyidx,
  			  sta ? sta->sta.addr : bcast_addr, ret);

   out_unsupported:
  	switch (key->conf.cipher) {
  	case WLAN_CIPHER_SUITE_WEP40:
  	case WLAN_CIPHER_SUITE_WEP104:
  	case WLAN_CIPHER_SUITE_TKIP:
  	case WLAN_CIPHER_SUITE_CCMP:

  	case WLAN_CIPHER_SUITE_CCMP_256:

  	case WLAN_CIPHER_SUITE_AES_CMAC:

  	case WLAN_CIPHER_SUITE_BIP_CMAC_256:

  	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
  	case WLAN_CIPHER_SUITE_BIP_GMAC_256:

  	case WLAN_CIPHER_SUITE_GCMP:
  	case WLAN_CIPHER_SUITE_GCMP_256:

  		/* all of these we can do in software - if driver can */
  		if (ret == 1)
  			return 0;

  		if (ieee80211_hw_check(&key->local->hw, SW_CRYPTO_CONTROL))

  			return -EINVAL;

  		return 0;
  	default:
  		return -EINVAL;

  	}

  }
  
  static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
  {

  	struct ieee80211_sub_if_data *sdata;

  	struct sta_info *sta;

  	int ret;

  	might_sleep();

  	if (!key || !key->local->ops->set_key)

  		return;

  	assert_key_lock(key->local);
  
  	if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))

  		return;

  	sta = key->sta;

  	sdata = key->sdata;

  	if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
  				 IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
  				 IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))

  		increment_tailroom_need_count(sdata);

  	key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;

  	ret = drv_set_key(key->local, DISABLE_KEY, sdata,

  			  sta ? &sta->sta : NULL, &key->conf);

  
  	if (ret)

  		sdata_err(sdata,

  			  "failed to remove key (%d, %pM) from hardware (%d)
  ",

  			  key->conf.keyidx,
  			  sta ? sta->sta.addr : bcast_addr, ret);

  }

  int ieee80211_set_tx_key(struct ieee80211_key *key)
  {
  	struct sta_info *sta = key->sta;
  	struct ieee80211_local *local = key->local;

  
  	assert_key_lock(local);

  	sta->ptk_idx = key->conf.keyidx;

  	if (!ieee80211_hw_check(&local->hw, AMPDU_KEYBORDER_SUPPORT))
  		clear_sta_flag(sta, WLAN_STA_BLOCK_BA);

  	ieee80211_check_fast_xmit(sta);
  
  	return 0;
  }

  static void ieee80211_pairwise_rekey(struct ieee80211_key *old,
  				     struct ieee80211_key *new)

  {

  	struct ieee80211_local *local = new->local;
  	struct sta_info *sta = new->sta;
  	int i;

  	assert_key_lock(local);

  	if (new->conf.flags & IEEE80211_KEY_FLAG_NO_AUTO_TX) {
  		/* Extended Key ID key install, initial one or rekey */

  		if (sta->ptk_idx != INVALID_PTK_KEYIDX &&
  		    !ieee80211_hw_check(&local->hw, AMPDU_KEYBORDER_SUPPORT)) {

  			/* Aggregation Sessions with Extended Key ID must not
  			 * mix MPDUs with different keyIDs within one A-MPDU.

  			 * Tear down running Tx aggregation sessions and block
  			 * new Rx/Tx aggregation requests during rekey to

  			 * ensure there are no A-MPDUs when the driver is not
  			 * supporting A-MPDU key borders. (Blocking Tx only
  			 * would be sufficient but WLAN_STA_BLOCK_BA gets the
  			 * job done for the few ms we need it.)

  			 */
  			set_sta_flag(sta, WLAN_STA_BLOCK_BA);
  			mutex_lock(&sta->ampdu_mlme.mtx);
  			for (i = 0; i <  IEEE80211_NUM_TIDS; i++)
  				___ieee80211_stop_tx_ba_session(sta, i,
  								AGG_STOP_LOCAL_REQUEST);
  			mutex_unlock(&sta->ampdu_mlme.mtx);
  		}
  	} else if (old) {
  		/* Rekey without Extended Key ID.
  		 * Aggregation sessions are OK when running on SW crypto.
  		 * A broken remote STA may cause issues not observed with HW
  		 * crypto, though.
  		 */
  		if (!(old->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
  			return;

  		/* Stop Tx till we are on the new key */
  		old->flags |= KEY_FLAG_TAINTED;

  		ieee80211_clear_fast_xmit(sta);

  		if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION)) {
  			set_sta_flag(sta, WLAN_STA_BLOCK_BA);
  			ieee80211_sta_tear_down_BA_sessions(sta,
  							    AGG_STOP_LOCAL_REQUEST);
  		}

  		if (!wiphy_ext_feature_isset(local->hw.wiphy,
  					     NL80211_EXT_FEATURE_CAN_REPLACE_PTK0)) {
  			pr_warn_ratelimited("Rekeying PTK for STA %pM but driver can't safely do that.",
  					    sta->sta.addr);
  			/* Flushing the driver queues *may* help prevent
  			 * the clear text leaks and freezes.
  			 */

  			ieee80211_flush_queues(local, old->sdata, false);

  		}
  	}

  }
  
  static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,

  					int idx, bool uni, bool multi)

  {
  	struct ieee80211_key *key = NULL;

  	assert_key_lock(sdata->local);

  	if (idx >= 0 && idx < NUM_DEFAULT_KEYS)

  		key = key_mtx_dereference(sdata->local, sdata->keys[idx]);

  	if (uni) {

  		rcu_assign_pointer(sdata->default_unicast_key, key);

  		ieee80211_check_fast_xmit_iface(sdata);

  		if (sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
  			drv_set_default_unicast_key(sdata->local, sdata, idx);

  	}

  	if (multi)
  		rcu_assign_pointer(sdata->default_multicast_key, key);

  	ieee80211_debugfs_key_update_default(sdata);

  }

  void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
  			       bool uni, bool multi)

  {

  	mutex_lock(&sdata->local->key_mtx);

  	__ieee80211_set_default_key(sdata, idx, uni, multi);

  	mutex_unlock(&sdata->local->key_mtx);

  }

  static void
  __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx)
  {
  	struct ieee80211_key *key = NULL;

  	assert_key_lock(sdata->local);

  	if (idx >= NUM_DEFAULT_KEYS &&
  	    idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)

  		key = key_mtx_dereference(sdata->local, sdata->keys[idx]);

  
  	rcu_assign_pointer(sdata->default_mgmt_key, key);

  	ieee80211_debugfs_key_update_default(sdata);

  }
  
  void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,
  				    int idx)
  {

  	mutex_lock(&sdata->local->key_mtx);

  	__ieee80211_set_default_mgmt_key(sdata, idx);

  	mutex_unlock(&sdata->local->key_mtx);

  }

  static int ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,

  				  struct sta_info *sta,
  				  bool pairwise,
  				  struct ieee80211_key *old,
  				  struct ieee80211_key *new)

  {

  	int idx;

  	int ret = 0;

  	bool defunikey, defmultikey, defmgmtkey;

  	/* caller must provide at least one old/new */
  	if (WARN_ON(!new && !old))

  		return 0;

  	if (new)

  		list_add_tail_rcu(&new->list, &sdata->key_list);

  	WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx);

  	if (new && sta && pairwise) {
  		/* Unicast rekey needs special handling. With Extended Key ID
  		 * old is still NULL for the first rekey.
  		 */
  		ieee80211_pairwise_rekey(old, new);
  	}

  	if (old) {

  		idx = old->conf.keyidx;

  
  		if (old->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
  			ieee80211_key_disable_hw_accel(old);
  
  			if (new)
  				ret = ieee80211_key_enable_hw_accel(new);
  		}

  	} else {

  		/* new must be provided in case old is not */

  		idx = new->conf.keyidx;

  		if (!new->local->wowlan)

  			ret = ieee80211_key_enable_hw_accel(new);

  	}
  
  	if (ret)
  		return ret;

  	if (sta) {
  		if (pairwise) {
  			rcu_assign_pointer(sta->ptk[idx], new);

  			if (new &&
  			    !(new->conf.flags & IEEE80211_KEY_FLAG_NO_AUTO_TX)) {
  				sta->ptk_idx = idx;

  				clear_sta_flag(sta, WLAN_STA_BLOCK_BA);
  				ieee80211_check_fast_xmit(sta);
  			}

  		} else {
  			rcu_assign_pointer(sta->gtk[idx], new);

  		}

  		/* Only needed for transition from no key -> key.
  		 * Still triggers unnecessary when using Extended Key ID
  		 * and installing the second key ID the first time.
  		 */
  		if (new && !old)

  			ieee80211_check_fast_rx(sta);

  	} else {

  		defunikey = old &&
  			old == key_mtx_dereference(sdata->local,
  						sdata->default_unicast_key);
  		defmultikey = old &&
  			old == key_mtx_dereference(sdata->local,
  						sdata->default_multicast_key);
  		defmgmtkey = old &&
  			old == key_mtx_dereference(sdata->local,
  						sdata->default_mgmt_key);

  		if (defunikey && !new)
  			__ieee80211_set_default_key(sdata, -1, true, false);
  		if (defmultikey && !new)
  			__ieee80211_set_default_key(sdata, -1, false, true);

  		if (defmgmtkey && !new)
  			__ieee80211_set_default_mgmt_key(sdata, -1);

  
  		rcu_assign_pointer(sdata->keys[idx], new);

  		if (defunikey && new)
  			__ieee80211_set_default_key(sdata, new->conf.keyidx,
  						    true, false);
  		if (defmultikey && new)
  			__ieee80211_set_default_key(sdata, new->conf.keyidx,
  						    false, true);

  		if (defmgmtkey && new)
  			__ieee80211_set_default_mgmt_key(sdata,
  							 new->conf.keyidx);

  	}

  	if (old)

  		list_del_rcu(&old->list);

  
  	return 0;

  }

  struct ieee80211_key *
  ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
  		    const u8 *key_data,
  		    size_t seq_len, const u8 *seq,
  		    const struct ieee80211_cipher_scheme *cs)

  {
  	struct ieee80211_key *key;

  	int i, j, err;

  	if (WARN_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS))
  		return ERR_PTR(-EINVAL);

  
  	key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);

  	if (!key)

  		return ERR_PTR(-ENOMEM);

  
  	/*
  	 * Default to software encryption; we'll later upload the
  	 * key to the hardware if possible.
  	 */

  	key->conf.flags = 0;
  	key->flags = 0;

  	key->conf.cipher = cipher;

  	key->conf.keyidx = idx;
  	key->conf.keylen = key_len;

  	switch (cipher) {
  	case WLAN_CIPHER_SUITE_WEP40:
  	case WLAN_CIPHER_SUITE_WEP104:

  		key->conf.iv_len = IEEE80211_WEP_IV_LEN;
  		key->conf.icv_len = IEEE80211_WEP_ICV_LEN;

  		break;

  	case WLAN_CIPHER_SUITE_TKIP:

  		key->conf.iv_len = IEEE80211_TKIP_IV_LEN;
  		key->conf.icv_len = IEEE80211_TKIP_ICV_LEN;

  		if (seq) {

  			for (i = 0; i < IEEE80211_NUM_TIDS; i++) {

  				key->u.tkip.rx[i].iv32 =
  					get_unaligned_le32(&seq[2]);
  				key->u.tkip.rx[i].iv16 =
  					get_unaligned_le16(seq);
  			}
  		}

  		spin_lock_init(&key->u.tkip.txlock);

  		break;

  	case WLAN_CIPHER_SUITE_CCMP:

  		key->conf.iv_len = IEEE80211_CCMP_HDR_LEN;
  		key->conf.icv_len = IEEE80211_CCMP_MIC_LEN;

  		if (seq) {

  			for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)

  				for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++)

  					key->u.ccmp.rx_pn[i][j] =

  						seq[IEEE80211_CCMP_PN_LEN - j - 1];

  		}

  		/*
  		 * Initialize AES key state here as an optimization so that
  		 * it does not need to be initialized for every packet.
  		 */

  		key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
  			key_data, key_len, IEEE80211_CCMP_MIC_LEN);
  		if (IS_ERR(key->u.ccmp.tfm)) {
  			err = PTR_ERR(key->u.ccmp.tfm);
  			kfree(key);
  			return ERR_PTR(err);
  		}
  		break;
  	case WLAN_CIPHER_SUITE_CCMP_256:
  		key->conf.iv_len = IEEE80211_CCMP_256_HDR_LEN;
  		key->conf.icv_len = IEEE80211_CCMP_256_MIC_LEN;
  		for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
  			for (j = 0; j < IEEE80211_CCMP_256_PN_LEN; j++)
  				key->u.ccmp.rx_pn[i][j] =
  					seq[IEEE80211_CCMP_256_PN_LEN - j - 1];
  		/* Initialize AES key state here as an optimization so that
  		 * it does not need to be initialized for every packet.
  		 */
  		key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(
  			key_data, key_len, IEEE80211_CCMP_256_MIC_LEN);

  		if (IS_ERR(key->u.ccmp.tfm)) {
  			err = PTR_ERR(key->u.ccmp.tfm);

  			kfree(key);

  			return ERR_PTR(err);

  		}

  		break;
  	case WLAN_CIPHER_SUITE_AES_CMAC:

  	case WLAN_CIPHER_SUITE_BIP_CMAC_256:

  		key->conf.iv_len = 0;

  		if (cipher == WLAN_CIPHER_SUITE_AES_CMAC)
  			key->conf.icv_len = sizeof(struct ieee80211_mmie);
  		else
  			key->conf.icv_len = sizeof(struct ieee80211_mmie_16);

  		if (seq)

  			for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++)

  				key->u.aes_cmac.rx_pn[j] =

  					seq[IEEE80211_CMAC_PN_LEN - j - 1];

  		/*
  		 * Initialize AES key state here as an optimization so that
  		 * it does not need to be initialized for every packet.
  		 */
  		key->u.aes_cmac.tfm =

  			ieee80211_aes_cmac_key_setup(key_data, key_len);

  		if (IS_ERR(key->u.aes_cmac.tfm)) {
  			err = PTR_ERR(key->u.aes_cmac.tfm);

  			kfree(key);

  			return ERR_PTR(err);

  		}

  		break;

  	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
  	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
  		key->conf.iv_len = 0;
  		key->conf.icv_len = sizeof(struct ieee80211_mmie_16);
  		if (seq)
  			for (j = 0; j < IEEE80211_GMAC_PN_LEN; j++)
  				key->u.aes_gmac.rx_pn[j] =
  					seq[IEEE80211_GMAC_PN_LEN - j - 1];
  		/* Initialize AES key state here as an optimization so that
  		 * it does not need to be initialized for every packet.
  		 */
  		key->u.aes_gmac.tfm =
  			ieee80211_aes_gmac_key_setup(key_data, key_len);
  		if (IS_ERR(key->u.aes_gmac.tfm)) {
  			err = PTR_ERR(key->u.aes_gmac.tfm);
  			kfree(key);
  			return ERR_PTR(err);
  		}
  		break;

  	case WLAN_CIPHER_SUITE_GCMP:
  	case WLAN_CIPHER_SUITE_GCMP_256:
  		key->conf.iv_len = IEEE80211_GCMP_HDR_LEN;
  		key->conf.icv_len = IEEE80211_GCMP_MIC_LEN;
  		for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++)
  			for (j = 0; j < IEEE80211_GCMP_PN_LEN; j++)
  				key->u.gcmp.rx_pn[i][j] =
  					seq[IEEE80211_GCMP_PN_LEN - j - 1];
  		/* Initialize AES key state here as an optimization so that
  		 * it does not need to be initialized for every packet.
  		 */
  		key->u.gcmp.tfm = ieee80211_aes_gcm_key_setup_encrypt(key_data,
  								      key_len);
  		if (IS_ERR(key->u.gcmp.tfm)) {
  			err = PTR_ERR(key->u.gcmp.tfm);
  			kfree(key);
  			return ERR_PTR(err);
  		}
  		break;

  	default:
  		if (cs) {

  			if (seq_len && seq_len != cs->pn_len) {
  				kfree(key);
  				return ERR_PTR(-EINVAL);
  			}

  
  			key->conf.iv_len = cs->hdr_len;
  			key->conf.icv_len = cs->mic_len;
  			for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)

  				for (j = 0; j < seq_len; j++)

  					key->u.gen.rx_pn[i][j] =

  							seq[seq_len - j - 1];

  			key->flags |= KEY_FLAG_CIPHER_SCHEME;

  		}

  	}

  	memcpy(key->conf.key, key_data, key_len);
  	INIT_LIST_HEAD(&key->list);

  	return key;
  }

  static void ieee80211_key_free_common(struct ieee80211_key *key)
  {

  	switch (key->conf.cipher) {
  	case WLAN_CIPHER_SUITE_CCMP:

  	case WLAN_CIPHER_SUITE_CCMP_256:

  		ieee80211_aes_key_free(key->u.ccmp.tfm);

  		break;
  	case WLAN_CIPHER_SUITE_AES_CMAC:

  	case WLAN_CIPHER_SUITE_BIP_CMAC_256:

  		ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);

  		break;

  	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
  	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
  		ieee80211_aes_gmac_key_free(key->u.aes_gmac.tfm);
  		break;

  	case WLAN_CIPHER_SUITE_GCMP:
  	case WLAN_CIPHER_SUITE_GCMP_256:
  		ieee80211_aes_gcm_key_free(key->u.gcmp.tfm);
  		break;
  	}

  	kzfree(key);

  }

  static void __ieee80211_key_destroy(struct ieee80211_key *key,
  				    bool delay_tailroom)

  {

  	if (key->local) {

  		struct ieee80211_sub_if_data *sdata = key->sdata;

  		ieee80211_debugfs_key_remove(key);

  
  		if (delay_tailroom) {
  			/* see ieee80211_delayed_tailroom_dec */
  			sdata->crypto_tx_tailroom_pending_dec++;
  			schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
  					      HZ/2);
  		} else {

  			decrease_tailroom_need_count(sdata, 1);

  		}

  	}

  	ieee80211_key_free_common(key);
  }

  static void ieee80211_key_destroy(struct ieee80211_key *key,
  				  bool delay_tailroom)
  {
  	if (!key)
  		return;
  
  	/*

  	 * Synchronize so the TX path and rcu key iterators
  	 * can no longer be using this key before we free/remove it.

  	 */
  	synchronize_net();
  
  	__ieee80211_key_destroy(key, delay_tailroom);
  }

  void ieee80211_key_free_unused(struct ieee80211_key *key)
  {
  	WARN_ON(key->sdata || key->local);
  	ieee80211_key_free_common(key);

  }

  static bool ieee80211_key_identical(struct ieee80211_sub_if_data *sdata,
  				    struct ieee80211_key *old,
  				    struct ieee80211_key *new)
  {
  	u8 tkip_old[WLAN_KEY_LEN_TKIP], tkip_new[WLAN_KEY_LEN_TKIP];
  	u8 *tk_old, *tk_new;
  
  	if (!old || new->conf.keylen != old->conf.keylen)
  		return false;
  
  	tk_old = old->conf.key;
  	tk_new = new->conf.key;
  
  	/*
  	 * In station mode, don't compare the TX MIC key, as it's never used
  	 * and offloaded rekeying may not care to send it to the host. This
  	 * is the case in iwlwifi, for example.
  	 */
  	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
  	    new->conf.cipher == WLAN_CIPHER_SUITE_TKIP &&
  	    new->conf.keylen == WLAN_KEY_LEN_TKIP &&
  	    !(new->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
  		memcpy(tkip_old, tk_old, WLAN_KEY_LEN_TKIP);
  		memcpy(tkip_new, tk_new, WLAN_KEY_LEN_TKIP);
  		memset(tkip_old + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
  		memset(tkip_new + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8);
  		tk_old = tkip_old;
  		tk_new = tkip_new;
  	}
  
  	return !crypto_memneq(tk_old, tk_new, new->conf.keylen);
  }

  int ieee80211_key_link(struct ieee80211_key *key,
  		       struct ieee80211_sub_if_data *sdata,
  		       struct sta_info *sta)

  {
  	struct ieee80211_key *old_key;

  	int idx = key->conf.keyidx;
  	bool pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
  	/*
  	 * We want to delay tailroom updates only for station - in that
  	 * case it helps roaming speed, but in other cases it hurts and
  	 * can cause warnings to appear.
  	 */
  	bool delay_tailroom = sdata->vif.type == NL80211_IFTYPE_STATION;

  	int ret = -EOPNOTSUPP;

  	mutex_lock(&sdata->local->key_mtx);

  	if (sta && pairwise) {
  		struct ieee80211_key *alt_key;

  		old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]);

  		alt_key = key_mtx_dereference(sdata->local, sta->ptk[idx ^ 1]);
  
  		/* The rekey code assumes that the old and new key are using
  		 * the same cipher. Enforce the assumption for pairwise keys.
  		 */

  		if ((alt_key && alt_key->conf.cipher != key->conf.cipher) ||
  		    (old_key && old_key->conf.cipher != key->conf.cipher))

  			goto out;
  	} else if (sta) {

  		old_key = key_mtx_dereference(sdata->local, sta->gtk[idx]);

  	} else {

  		old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]);

  	}
  
  	/* Non-pairwise keys must also not switch the cipher on rekey */
  	if (!pairwise) {

  		if (old_key && old_key->conf.cipher != key->conf.cipher)

  			goto out;
  	}

  	/*
  	 * Silently accept key re-installation without really installing the
  	 * new version of the key to avoid nonce reuse or replay issues.
  	 */

  	if (ieee80211_key_identical(sdata, old_key, key)) {

  		ieee80211_key_free_unused(key);
  		ret = 0;
  		goto out;
  	}
  
  	key->local = sdata->local;
  	key->sdata = sdata;
  	key->sta = sta;

  	increment_tailroom_need_count(sdata);

  	ret = ieee80211_key_replace(sdata, sta, pairwise, old_key, key);

  	if (!ret) {
  		ieee80211_debugfs_key_add(key);
  		ieee80211_key_destroy(old_key, delay_tailroom);

  	} else {

  		ieee80211_key_free(key, delay_tailroom);

  	}

   out:

  	mutex_unlock(&sdata->local->key_mtx);

  
  	return ret;

  }

  void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)

  {

  	if (!key)
  		return;

  	/*
  	 * Replace key with nothingness if it was ever used.
  	 */

  	if (key->sdata)

  		ieee80211_key_replace(key->sdata, key->sta,

  				key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
  				key, NULL);

  	ieee80211_key_destroy(key, delay_tailroom);

  }

  void ieee80211_reenable_keys(struct ieee80211_sub_if_data *sdata)

  {
  	struct ieee80211_key *key;

  	struct ieee80211_sub_if_data *vlan;

  	ASSERT_RTNL();

  	mutex_lock(&sdata->local->key_mtx);
  
  	sdata->crypto_tx_tailroom_needed_cnt = 0;

  	sdata->crypto_tx_tailroom_pending_dec = 0;

  
  	if (sdata->vif.type == NL80211_IFTYPE_AP) {

  		list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) {

  			vlan->crypto_tx_tailroom_needed_cnt = 0;

  			vlan->crypto_tx_tailroom_pending_dec = 0;
  		}
  	}
  
  	if (ieee80211_sdata_running(sdata)) {
  		list_for_each_entry(key, &sdata->key_list, list) {
  			increment_tailroom_need_count(sdata);
  			ieee80211_key_enable_hw_accel(key);
  		}

  	}
  
  	mutex_unlock(&sdata->local->key_mtx);
  }

  void ieee80211_iter_keys(struct ieee80211_hw *hw,
  			 struct ieee80211_vif *vif,
  			 void (*iter)(struct ieee80211_hw *hw,
  				      struct ieee80211_vif *vif,
  				      struct ieee80211_sta *sta,
  				      struct ieee80211_key_conf *key,
  				      void *data),
  			 void *iter_data)
  {
  	struct ieee80211_local *local = hw_to_local(hw);

  	struct ieee80211_key *key, *tmp;

  	struct ieee80211_sub_if_data *sdata;
  
  	ASSERT_RTNL();
  
  	mutex_lock(&local->key_mtx);
  	if (vif) {
  		sdata = vif_to_sdata(vif);

  		list_for_each_entry_safe(key, tmp, &sdata->key_list, list)

  			iter(hw, &sdata->vif,
  			     key->sta ? &key->sta->sta : NULL,
  			     &key->conf, iter_data);
  	} else {
  		list_for_each_entry(sdata, &local->interfaces, list)

  			list_for_each_entry_safe(key, tmp,
  						 &sdata->key_list, list)

  				iter(hw, &sdata->vif,
  				     key->sta ? &key->sta->sta : NULL,
  				     &key->conf, iter_data);
  	}
  	mutex_unlock(&local->key_mtx);
  }
  EXPORT_SYMBOL(ieee80211_iter_keys);

  static void
  _ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
  			 struct ieee80211_sub_if_data *sdata,
  			 void (*iter)(struct ieee80211_hw *hw,
  				      struct ieee80211_vif *vif,
  				      struct ieee80211_sta *sta,
  				      struct ieee80211_key_conf *key,
  				      void *data),
  			 void *iter_data)
  {
  	struct ieee80211_key *key;
  
  	list_for_each_entry_rcu(key, &sdata->key_list, list) {
  		/* skip keys of station in removal process */
  		if (key->sta && key->sta->removed)
  			continue;
  		if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
  			continue;
  
  		iter(hw, &sdata->vif,
  		     key->sta ? &key->sta->sta : NULL,
  		     &key->conf, iter_data);
  	}
  }
  
  void ieee80211_iter_keys_rcu(struct ieee80211_hw *hw,
  			     struct ieee80211_vif *vif,
  			     void (*iter)(struct ieee80211_hw *hw,
  					  struct ieee80211_vif *vif,
  					  struct ieee80211_sta *sta,
  					  struct ieee80211_key_conf *key,
  					  void *data),
  			     void *iter_data)
  {
  	struct ieee80211_local *local = hw_to_local(hw);
  	struct ieee80211_sub_if_data *sdata;
  
  	if (vif) {
  		sdata = vif_to_sdata(vif);
  		_ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
  	} else {
  		list_for_each_entry_rcu(sdata, &local->interfaces, list)
  			_ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data);
  	}
  }
  EXPORT_SYMBOL(ieee80211_iter_keys_rcu);

  static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
  				      struct list_head *keys)

  {
  	struct ieee80211_key *key, *tmp;

  	decrease_tailroom_need_count(sdata,
  				     sdata->crypto_tx_tailroom_pending_dec);

  	sdata->crypto_tx_tailroom_pending_dec = 0;

  	ieee80211_debugfs_key_remove_mgmt_default(sdata);

  	list_for_each_entry_safe(key, tmp, &sdata->key_list, list) {
  		ieee80211_key_replace(key->sdata, key->sta,
  				key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
  				key, NULL);

  		list_add_tail(&key->list, keys);

  	}

  	ieee80211_debugfs_key_update_default(sdata);

  }

  void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
  			 bool force_synchronize)
  {
  	struct ieee80211_local *local = sdata->local;
  	struct ieee80211_sub_if_data *vlan;

  	struct ieee80211_sub_if_data *master;

  	struct ieee80211_key *key, *tmp;
  	LIST_HEAD(keys);
  
  	cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
  
  	mutex_lock(&local->key_mtx);
  
  	ieee80211_free_keys_iface(sdata, &keys);
  
  	if (sdata->vif.type == NL80211_IFTYPE_AP) {
  		list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
  			ieee80211_free_keys_iface(vlan, &keys);

  	}

  	if (!list_empty(&keys) || force_synchronize)
  		synchronize_net();
  	list_for_each_entry_safe(key, tmp, &keys, list)
  		__ieee80211_key_destroy(key, false);

  	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
  		if (sdata->bss) {
  			master = container_of(sdata->bss,
  					      struct ieee80211_sub_if_data,
  					      u.ap);
  
  			WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt !=
  				     master->crypto_tx_tailroom_needed_cnt);
  		}
  	} else {
  		WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
  			     sdata->crypto_tx_tailroom_pending_dec);
  	}

  	if (sdata->vif.type == NL80211_IFTYPE_AP) {
  		list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
  			WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
  				     vlan->crypto_tx_tailroom_pending_dec);
  	}

  	mutex_unlock(&local->key_mtx);

  }

  void ieee80211_free_sta_keys(struct ieee80211_local *local,
  			     struct sta_info *sta)
  {

  	struct ieee80211_key *key;

  	int i;
  
  	mutex_lock(&local->key_mtx);

  	for (i = 0; i < ARRAY_SIZE(sta->gtk); i++) {

  		key = key_mtx_dereference(local, sta->gtk[i]);
  		if (!key)
  			continue;
  		ieee80211_key_replace(key->sdata, key->sta,
  				key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
  				key, NULL);

  		__ieee80211_key_destroy(key, key->sdata->vif.type ==
  					NL80211_IFTYPE_STATION);

  	}

  	for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
  		key = key_mtx_dereference(local, sta->ptk[i]);
  		if (!key)
  			continue;

  		ieee80211_key_replace(key->sdata, key->sta,
  				key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
  				key, NULL);

  		__ieee80211_key_destroy(key, key->sdata->vif.type ==
  					NL80211_IFTYPE_STATION);

  	}

  
  	mutex_unlock(&local->key_mtx);
  }

  void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
  {
  	struct ieee80211_sub_if_data *sdata;
  
  	sdata = container_of(wk, struct ieee80211_sub_if_data,
  			     dec_tailroom_needed_wk.work);
  
  	/*
  	 * The reason for the delayed tailroom needed decrementing is to
  	 * make roaming faster: during roaming, all keys are first deleted
  	 * and then new keys are installed. The first new key causes the
  	 * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes
  	 * the cost of synchronize_net() (which can be slow). Avoid this
  	 * by deferring the crypto_tx_tailroom_needed_cnt decrementing on
  	 * key removal for a while, so if we roam the value is larger than
  	 * zero and no 0->1 transition happens.
  	 *
  	 * The cost is that if the AP switching was from an AP with keys
  	 * to one without, we still allocate tailroom while it would no
  	 * longer be needed. However, in the typical (fast) roaming case
  	 * within an ESS this usually won't happen.
  	 */
  
  	mutex_lock(&sdata->local->key_mtx);

  	decrease_tailroom_need_count(sdata,
  				     sdata->crypto_tx_tailroom_pending_dec);

  	sdata->crypto_tx_tailroom_pending_dec = 0;
  	mutex_unlock(&sdata->local->key_mtx);
  }

  
  void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid,
  				const u8 *replay_ctr, gfp_t gfp)
  {
  	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
  
  	trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr);
  
  	cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp);
  }
  EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify);

  void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf,
  			      int tid, struct ieee80211_key_seq *seq)
  {
  	struct ieee80211_key *key;
  	const u8 *pn;
  
  	key = container_of(keyconf, struct ieee80211_key, conf);
  
  	switch (key->conf.cipher) {
  	case WLAN_CIPHER_SUITE_TKIP:

  		if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))

  			return;
  		seq->tkip.iv32 = key->u.tkip.rx[tid].iv32;
  		seq->tkip.iv16 = key->u.tkip.rx[tid].iv16;
  		break;
  	case WLAN_CIPHER_SUITE_CCMP:

  	case WLAN_CIPHER_SUITE_CCMP_256:

  		if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))

  			return;
  		if (tid < 0)

  			pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];

  		else
  			pn = key->u.ccmp.rx_pn[tid];

  		memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN);

  		break;
  	case WLAN_CIPHER_SUITE_AES_CMAC:

  	case WLAN_CIPHER_SUITE_BIP_CMAC_256:

  		if (WARN_ON(tid != 0))
  			return;
  		pn = key->u.aes_cmac.rx_pn;

  		memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN);

  		break;

  	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
  	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
  		if (WARN_ON(tid != 0))
  			return;
  		pn = key->u.aes_gmac.rx_pn;
  		memcpy(seq->aes_gmac.pn, pn, IEEE80211_GMAC_PN_LEN);
  		break;

  	case WLAN_CIPHER_SUITE_GCMP:
  	case WLAN_CIPHER_SUITE_GCMP_256:
  		if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
  			return;
  		if (tid < 0)
  			pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
  		else
  			pn = key->u.gcmp.rx_pn[tid];
  		memcpy(seq->gcmp.pn, pn, IEEE80211_GCMP_PN_LEN);
  		break;

  	}
  }
  EXPORT_SYMBOL(ieee80211_get_key_rx_seq);

  void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf,
  			      int tid, struct ieee80211_key_seq *seq)
  {
  	struct ieee80211_key *key;
  	u8 *pn;
  
  	key = container_of(keyconf, struct ieee80211_key, conf);
  
  	switch (key->conf.cipher) {
  	case WLAN_CIPHER_SUITE_TKIP:
  		if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS))
  			return;
  		key->u.tkip.rx[tid].iv32 = seq->tkip.iv32;
  		key->u.tkip.rx[tid].iv16 = seq->tkip.iv16;
  		break;
  	case WLAN_CIPHER_SUITE_CCMP:

  	case WLAN_CIPHER_SUITE_CCMP_256:

  		if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
  			return;
  		if (tid < 0)
  			pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS];
  		else
  			pn = key->u.ccmp.rx_pn[tid];
  		memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN);
  		break;
  	case WLAN_CIPHER_SUITE_AES_CMAC:

  	case WLAN_CIPHER_SUITE_BIP_CMAC_256:

  		if (WARN_ON(tid != 0))
  			return;
  		pn = key->u.aes_cmac.rx_pn;
  		memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN);
  		break;

  	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
  	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
  		if (WARN_ON(tid != 0))
  			return;
  		pn = key->u.aes_gmac.rx_pn;
  		memcpy(pn, seq->aes_gmac.pn, IEEE80211_GMAC_PN_LEN);
  		break;

  	case WLAN_CIPHER_SUITE_GCMP:
  	case WLAN_CIPHER_SUITE_GCMP_256:
  		if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS))
  			return;
  		if (tid < 0)
  			pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS];
  		else
  			pn = key->u.gcmp.rx_pn[tid];
  		memcpy(pn, seq->gcmp.pn, IEEE80211_GCMP_PN_LEN);
  		break;

  	default:
  		WARN_ON(1);
  		break;
  	}
  }
  EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq);
  
  void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
  {
  	struct ieee80211_key *key;
  
  	key = container_of(keyconf, struct ieee80211_key, conf);
  
  	assert_key_lock(key->local);
  
  	/*
  	 * if key was uploaded, we assume the driver will/has remove(d)
  	 * it, so adjust bookkeeping accordingly
  	 */
  	if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
  		key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;

  		if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
  					 IEEE80211_KEY_FLAG_PUT_MIC_SPACE |
  					 IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))

  			increment_tailroom_need_count(key->sdata);
  	}
  
  	ieee80211_key_free(key, false);
  }
  EXPORT_SYMBOL_GPL(ieee80211_remove_key);
  
  struct ieee80211_key_conf *
  ieee80211_gtk_rekey_add(struct ieee80211_vif *vif,
  			struct ieee80211_key_conf *keyconf)
  {
  	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
  	struct ieee80211_local *local = sdata->local;
  	struct ieee80211_key *key;
  	int err;
  
  	if (WARN_ON(!local->wowlan))
  		return ERR_PTR(-EINVAL);
  
  	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
  		return ERR_PTR(-EINVAL);
  
  	key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx,
  				  keyconf->keylen, keyconf->key,

  				  0, NULL, NULL);

  	if (IS_ERR(key))

  		return ERR_CAST(key);

  
  	if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED)
  		key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT;
  
  	err = ieee80211_key_link(key, sdata, NULL);
  	if (err)
  		return ERR_PTR(err);
  
  	return &key->conf;
  }
  EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add);