mlme.c 70.7 KB
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/*
 * BSS client mode implementation
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 * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
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 * Copyright 2004, Instant802 Networks, Inc.
 * Copyright 2005, Devicescape Software, Inc.
 * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

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#include <linux/delay.h>
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#include <linux/if_ether.h>
#include <linux/skbuff.h>
#include <linux/if_arp.h>
#include <linux/etherdevice.h>
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#include <linux/rtnetlink.h>
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#include <linux/pm_qos_params.h>
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#include <linux/crc32.h>
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#include <linux/slab.h>
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#include <net/mac80211.h>
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#include <asm/unaligned.h>
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#include "ieee80211_i.h"
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#include "driver-ops.h"
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#include "rate.h"
#include "led.h"
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#define IEEE80211_MAX_NULLFUNC_TRIES 2
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#define IEEE80211_MAX_PROBE_TRIES 5
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/*
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 * Beacon loss timeout is calculated as N frames times the
 * advertised beacon interval.  This may need to be somewhat
 * higher than what hardware might detect to account for
 * delays in the host processing frames. But since we also
 * probe on beacon miss before declaring the connection lost
 * default to what we want.
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 */
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#define IEEE80211_BEACON_LOSS_COUNT	7

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/*
 * Time the connection can be idle before we probe
 * it to see if we can still talk to the AP.
 */
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#define IEEE80211_CONNECTION_IDLE_TIME	(30 * HZ)
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/*
 * Time we wait for a probe response after sending
 * a probe request because of beacon loss or for
 * checking the connection still works.
 */
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#define IEEE80211_PROBE_WAIT		(HZ / 2)
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/*
 * Weight given to the latest Beacon frame when calculating average signal
 * strength for Beacon frames received in the current BSS. This must be
 * between 1 and 15.
 */
#define IEEE80211_SIGNAL_AVE_WEIGHT	3

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/*
 * How many Beacon frames need to have been used in average signal strength
 * before starting to indicate signal change events.
 */
#define IEEE80211_SIGNAL_AVE_MIN_COUNT	4

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#define TMR_RUNNING_TIMER	0
#define TMR_RUNNING_CHANSW	1

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/*
 * All cfg80211 functions have to be called outside a locked
 * section so that they can acquire a lock themselves... This
 * is much simpler than queuing up things in cfg80211, but we
 * do need some indirection for that here.
 */
enum rx_mgmt_action {
	/* no action required */
	RX_MGMT_NONE,

	/* caller must call cfg80211_send_rx_auth() */
	RX_MGMT_CFG80211_AUTH,

	/* caller must call cfg80211_send_rx_assoc() */
	RX_MGMT_CFG80211_ASSOC,

	/* caller must call cfg80211_send_deauth() */
	RX_MGMT_CFG80211_DEAUTH,

	/* caller must call cfg80211_send_disassoc() */
	RX_MGMT_CFG80211_DISASSOC,

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	/* caller must tell cfg80211 about internal error */
	RX_MGMT_CFG80211_ASSOC_ERROR,
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};

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/* utils */
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static inline void ASSERT_MGD_MTX(struct ieee80211_if_managed *ifmgd)
{
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	lockdep_assert_held(&ifmgd->mtx);
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}

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/*
 * We can have multiple work items (and connection probing)
 * scheduling this timer, but we need to take care to only
 * reschedule it when it should fire _earlier_ than it was
 * asked for before, or if it's not pending right now. This
 * function ensures that. Note that it then is required to
 * run this function for all timeouts after the first one
 * has happened -- the work that runs from this timer will
 * do that.
 */
static void run_again(struct ieee80211_if_managed *ifmgd,
			     unsigned long timeout)
{
	ASSERT_MGD_MTX(ifmgd);

	if (!timer_pending(&ifmgd->timer) ||
	    time_before(timeout, ifmgd->timer.expires))
		mod_timer(&ifmgd->timer, timeout);
}

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void ieee80211_sta_reset_beacon_monitor(struct ieee80211_sub_if_data *sdata)
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{
	if (sdata->local->hw.flags & IEEE80211_HW_BEACON_FILTER)
		return;

	mod_timer(&sdata->u.mgd.bcn_mon_timer,
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		  round_jiffies_up(jiffies + sdata->u.mgd.beacon_timeout));
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}

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void ieee80211_sta_reset_conn_monitor(struct ieee80211_sub_if_data *sdata)
{
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	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;

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	if (sdata->local->hw.flags & IEEE80211_HW_CONNECTION_MONITOR)
		return;

	mod_timer(&sdata->u.mgd.conn_mon_timer,
		  round_jiffies_up(jiffies + IEEE80211_CONNECTION_IDLE_TIME));
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	ifmgd->probe_send_count = 0;
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}

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static int ecw2cw(int ecw)
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{
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	return (1 << ecw) - 1;
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}

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/*
 * ieee80211_enable_ht should be called only after the operating band
 * has been determined as ht configuration depends on the hw's
 * HT abilities for a specific band.
 */
static u32 ieee80211_enable_ht(struct ieee80211_sub_if_data *sdata,
			       struct ieee80211_ht_info *hti,
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			       const u8 *bssid, u16 ap_ht_cap_flags)
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{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_supported_band *sband;
	struct sta_info *sta;
	u32 changed = 0;
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	u16 ht_opmode;
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	bool enable_ht = true;
	enum nl80211_channel_type prev_chantype;
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	enum nl80211_channel_type channel_type = NL80211_CHAN_NO_HT;

	sband = local->hw.wiphy->bands[local->hw.conf.channel->band];

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	prev_chantype = sdata->vif.bss_conf.channel_type;

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	/* HT is not supported */
	if (!sband->ht_cap.ht_supported)
		enable_ht = false;

	/* check that channel matches the right operating channel */
	if (local->hw.conf.channel->center_freq !=
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	    ieee80211_channel_to_frequency(hti->control_chan, sband->band))
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		enable_ht = false;

	if (enable_ht) {
		channel_type = NL80211_CHAN_HT20;

		if (!(ap_ht_cap_flags & IEEE80211_HT_CAP_40MHZ_INTOLERANT) &&
		    (sband->ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) &&
		    (hti->ht_param & IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) {
			switch(hti->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) {
			case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
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				if (!(local->hw.conf.channel->flags &
				    IEEE80211_CHAN_NO_HT40PLUS))
					channel_type = NL80211_CHAN_HT40PLUS;
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				break;
			case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
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				if (!(local->hw.conf.channel->flags &
				    IEEE80211_CHAN_NO_HT40MINUS))
					channel_type = NL80211_CHAN_HT40MINUS;
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				break;
			}
		}
	}

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	if (local->tmp_channel)
		local->tmp_channel_type = channel_type;
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	if (!ieee80211_set_channel_type(local, sdata, channel_type)) {
		/* can only fail due to HT40+/- mismatch */
		channel_type = NL80211_CHAN_HT20;
		WARN_ON(!ieee80211_set_channel_type(local, sdata, channel_type));
	}
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	/* channel_type change automatically detected */
	ieee80211_hw_config(local, 0);
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	if (prev_chantype != channel_type) {
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		rcu_read_lock();
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		sta = sta_info_get(sdata, bssid);
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		if (sta)
			rate_control_rate_update(local, sband, sta,
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						 IEEE80211_RC_HT_CHANGED,
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						 channel_type);
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		rcu_read_unlock();
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	}
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	ht_opmode = le16_to_cpu(hti->operation_mode);
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	/* if bss configuration changed store the new one */
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	if (sdata->ht_opmode_valid != enable_ht ||
	    sdata->vif.bss_conf.ht_operation_mode != ht_opmode ||
	    prev_chantype != channel_type) {
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		changed |= BSS_CHANGED_HT;
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		sdata->vif.bss_conf.ht_operation_mode = ht_opmode;
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		sdata->ht_opmode_valid = enable_ht;
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	}

	return changed;
}

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/* frame sending functions */

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static void ieee80211_send_deauth_disassoc(struct ieee80211_sub_if_data *sdata,
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					   const u8 *bssid, u16 stype, u16 reason,
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					   void *cookie, bool send_frame)
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{
	struct ieee80211_local *local = sdata->local;
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	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
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	struct sk_buff *skb;
	struct ieee80211_mgmt *mgmt;
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	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*mgmt));
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	if (!skb) {
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		printk(KERN_DEBUG "%s: failed to allocate buffer for "
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		       "deauth/disassoc frame\n", sdata->name);
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		return;
	}
	skb_reserve(skb, local->hw.extra_tx_headroom);

	mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
	memset(mgmt, 0, 24);
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	memcpy(mgmt->da, bssid, ETH_ALEN);
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	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
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	memcpy(mgmt->bssid, bssid, ETH_ALEN);
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	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | stype);
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	skb_put(skb, 2);
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	/* u.deauth.reason_code == u.disassoc.reason_code */
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	mgmt->u.deauth.reason_code = cpu_to_le16(reason);

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	if (stype == IEEE80211_STYPE_DEAUTH)
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		if (cookie)
			__cfg80211_send_deauth(sdata->dev, (u8 *)mgmt, skb->len);
		else
			cfg80211_send_deauth(sdata->dev, (u8 *)mgmt, skb->len);
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	else
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		if (cookie)
			__cfg80211_send_disassoc(sdata->dev, (u8 *)mgmt, skb->len);
		else
			cfg80211_send_disassoc(sdata->dev, (u8 *)mgmt, skb->len);
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	if (!(ifmgd->flags & IEEE80211_STA_MFP_ENABLED))
		IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
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	if (send_frame)
		ieee80211_tx_skb(sdata, skb);
	else
		kfree_skb(skb);
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}

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void ieee80211_send_pspoll(struct ieee80211_local *local,
			   struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_pspoll *pspoll;
	struct sk_buff *skb;

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	skb = ieee80211_pspoll_get(&local->hw, &sdata->vif);
	if (!skb)
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		return;

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	pspoll = (struct ieee80211_pspoll *) skb->data;
	pspoll->frame_control |= cpu_to_le16(IEEE80211_FCTL_PM);
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	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
	ieee80211_tx_skb(sdata, skb);
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}

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void ieee80211_send_nullfunc(struct ieee80211_local *local,
			     struct ieee80211_sub_if_data *sdata,
			     int powersave)
{
	struct sk_buff *skb;
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	struct ieee80211_hdr_3addr *nullfunc;
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	skb = ieee80211_nullfunc_get(&local->hw, &sdata->vif);
	if (!skb)
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		return;

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	nullfunc = (struct ieee80211_hdr_3addr *) skb->data;
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	if (powersave)
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		nullfunc->frame_control |= cpu_to_le16(IEEE80211_FCTL_PM);
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	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
	ieee80211_tx_skb(sdata, skb);
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}

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static void ieee80211_send_4addr_nullfunc(struct ieee80211_local *local,
					  struct ieee80211_sub_if_data *sdata)
{
	struct sk_buff *skb;
	struct ieee80211_hdr *nullfunc;
	__le16 fc;

	if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_STATION))
		return;

	skb = dev_alloc_skb(local->hw.extra_tx_headroom + 30);
	if (!skb) {
		printk(KERN_DEBUG "%s: failed to allocate buffer for 4addr "
		       "nullfunc frame\n", sdata->name);
		return;
	}
	skb_reserve(skb, local->hw.extra_tx_headroom);

	nullfunc = (struct ieee80211_hdr *) skb_put(skb, 30);
	memset(nullfunc, 0, 30);
	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_NULLFUNC |
			 IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
	nullfunc->frame_control = fc;
	memcpy(nullfunc->addr1, sdata->u.mgd.bssid, ETH_ALEN);
	memcpy(nullfunc->addr2, sdata->vif.addr, ETH_ALEN);
	memcpy(nullfunc->addr3, sdata->u.mgd.bssid, ETH_ALEN);
	memcpy(nullfunc->addr4, sdata->vif.addr, ETH_ALEN);

	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
	ieee80211_tx_skb(sdata, skb);
}

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/* spectrum management related things */
static void ieee80211_chswitch_work(struct work_struct *work)
{
	struct ieee80211_sub_if_data *sdata =
		container_of(work, struct ieee80211_sub_if_data, u.mgd.chswitch_work);
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;

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	if (!ieee80211_sdata_running(sdata))
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		return;

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	mutex_lock(&ifmgd->mtx);
	if (!ifmgd->associated)
		goto out;
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	sdata->local->oper_channel = sdata->local->csa_channel;
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	if (!sdata->local->ops->channel_switch) {
		/* call "hw_config" only if doing sw channel switch */
		ieee80211_hw_config(sdata->local,
			IEEE80211_CONF_CHANGE_CHANNEL);
	}
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	/* XXX: shouldn't really modify cfg80211-owned data! */
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	ifmgd->associated->channel = sdata->local->oper_channel;
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	ieee80211_wake_queues_by_reason(&sdata->local->hw,
					IEEE80211_QUEUE_STOP_REASON_CSA);
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 out:
	ifmgd->flags &= ~IEEE80211_STA_CSA_RECEIVED;
	mutex_unlock(&ifmgd->mtx);
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}

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void ieee80211_chswitch_done(struct ieee80211_vif *vif, bool success)
{
	struct ieee80211_sub_if_data *sdata;
	struct ieee80211_if_managed *ifmgd;

	sdata = vif_to_sdata(vif);
	ifmgd = &sdata->u.mgd;

	trace_api_chswitch_done(sdata, success);
	if (!success) {
		/*
		 * If the channel switch was not successful, stay
		 * around on the old channel. We currently lack
		 * good handling of this situation, possibly we
		 * should just drop the association.
		 */
		sdata->local->csa_channel = sdata->local->oper_channel;
	}

	ieee80211_queue_work(&sdata->local->hw, &ifmgd->chswitch_work);
}
EXPORT_SYMBOL(ieee80211_chswitch_done);

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static void ieee80211_chswitch_timer(unsigned long data)
{
	struct ieee80211_sub_if_data *sdata =
		(struct ieee80211_sub_if_data *) data;
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;

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	if (sdata->local->quiescing) {
		set_bit(TMR_RUNNING_CHANSW, &ifmgd->timers_running);
		return;
	}

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	ieee80211_queue_work(&sdata->local->hw, &ifmgd->chswitch_work);
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}

void ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
				      struct ieee80211_channel_sw_ie *sw_elem,
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				      struct ieee80211_bss *bss,
				      u64 timestamp)
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{
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	struct cfg80211_bss *cbss =
		container_of((void *)bss, struct cfg80211_bss, priv);
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	struct ieee80211_channel *new_ch;
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
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	int new_freq = ieee80211_channel_to_frequency(sw_elem->new_ch_num,
						      cbss->channel->band);
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	ASSERT_MGD_MTX(ifmgd);

	if (!ifmgd->associated)
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		return;

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	if (sdata->local->scanning)
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		return;

	/* Disregard subsequent beacons if we are already running a timer
	   processing a CSA */

	if (ifmgd->flags & IEEE80211_STA_CSA_RECEIVED)
		return;

	new_ch = ieee80211_get_channel(sdata->local->hw.wiphy, new_freq);
	if (!new_ch || new_ch->flags & IEEE80211_CHAN_DISABLED)
		return;

	sdata->local->csa_channel = new_ch;

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	if (sdata->local->ops->channel_switch) {
		/* use driver's channel switch callback */
		struct ieee80211_channel_switch ch_switch;
		memset(&ch_switch, 0, sizeof(ch_switch));
		ch_switch.timestamp = timestamp;
		if (sw_elem->mode) {
			ch_switch.block_tx = true;
			ieee80211_stop_queues_by_reason(&sdata->local->hw,
					IEEE80211_QUEUE_STOP_REASON_CSA);
		}
		ch_switch.channel = new_ch;
		ch_switch.count = sw_elem->count;
		ifmgd->flags |= IEEE80211_STA_CSA_RECEIVED;
		drv_channel_switch(sdata->local, &ch_switch);
		return;
	}

	/* channel switch handled in software */
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	if (sw_elem->count <= 1) {
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		ieee80211_queue_work(&sdata->local->hw, &ifmgd->chswitch_work);
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	} else {
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		if (sw_elem->mode)
			ieee80211_stop_queues_by_reason(&sdata->local->hw,
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					IEEE80211_QUEUE_STOP_REASON_CSA);
		ifmgd->flags |= IEEE80211_STA_CSA_RECEIVED;
		mod_timer(&ifmgd->chswitch_timer,
			  jiffies +
			  msecs_to_jiffies(sw_elem->count *
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					   cbss->beacon_interval));
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	}
}

static void ieee80211_handle_pwr_constr(struct ieee80211_sub_if_data *sdata,
					u16 capab_info, u8 *pwr_constr_elem,
					u8 pwr_constr_elem_len)
{
	struct ieee80211_conf *conf = &sdata->local->hw.conf;

	if (!(capab_info & WLAN_CAPABILITY_SPECTRUM_MGMT))
		return;

	/* Power constraint IE length should be 1 octet */
	if (pwr_constr_elem_len != 1)
		return;

	if ((*pwr_constr_elem <= conf->channel->max_power) &&
	    (*pwr_constr_elem != sdata->local->power_constr_level)) {
		sdata->local->power_constr_level = *pwr_constr_elem;
		ieee80211_hw_config(sdata->local, 0);
	}
}

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void ieee80211_enable_dyn_ps(struct ieee80211_vif *vif)
{
	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_conf *conf = &local->hw.conf;

	WARN_ON(sdata->vif.type != NL80211_IFTYPE_STATION ||
		!(local->hw.flags & IEEE80211_HW_SUPPORTS_PS) ||
		(local->hw.flags & IEEE80211_HW_SUPPORTS_DYNAMIC_PS));

	local->disable_dynamic_ps = false;
	conf->dynamic_ps_timeout = local->dynamic_ps_user_timeout;
}
EXPORT_SYMBOL(ieee80211_enable_dyn_ps);

void ieee80211_disable_dyn_ps(struct ieee80211_vif *vif)
{
	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_conf *conf = &local->hw.conf;

	WARN_ON(sdata->vif.type != NL80211_IFTYPE_STATION ||
		!(local->hw.flags & IEEE80211_HW_SUPPORTS_PS) ||
		(local->hw.flags & IEEE80211_HW_SUPPORTS_DYNAMIC_PS));

	local->disable_dynamic_ps = true;
	conf->dynamic_ps_timeout = 0;
	del_timer_sync(&local->dynamic_ps_timer);
	ieee80211_queue_work(&local->hw,
			     &local->dynamic_ps_enable_work);
}
EXPORT_SYMBOL(ieee80211_disable_dyn_ps);

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/* powersave */
static void ieee80211_enable_ps(struct ieee80211_local *local,
				struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_conf *conf = &local->hw.conf;

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	/*
	 * If we are scanning right now then the parameters will
	 * take effect when scan finishes.
	 */
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	if (local->scanning)
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		return;

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	if (conf->dynamic_ps_timeout > 0 &&
	    !(local->hw.flags & IEEE80211_HW_SUPPORTS_DYNAMIC_PS)) {
		mod_timer(&local->dynamic_ps_timer, jiffies +
			  msecs_to_jiffies(conf->dynamic_ps_timeout));
	} else {
		if (local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK)
			ieee80211_send_nullfunc(local, sdata, 1);
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		if ((local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK) &&
		    (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS))
			return;

		conf->flags |= IEEE80211_CONF_PS;
		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
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	}
}

static void ieee80211_change_ps(struct ieee80211_local *local)
{
	struct ieee80211_conf *conf = &local->hw.conf;

	if (local->ps_sdata) {
		ieee80211_enable_ps(local, local->ps_sdata);
	} else if (conf->flags & IEEE80211_CONF_PS) {
		conf->flags &= ~IEEE80211_CONF_PS;
		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
		del_timer_sync(&local->dynamic_ps_timer);
		cancel_work_sync(&local->dynamic_ps_enable_work);
	}
}

/* need to hold RTNL or interface lock */
585
void ieee80211_recalc_ps(struct ieee80211_local *local, s32 latency)
586 587 588
{
	struct ieee80211_sub_if_data *sdata, *found = NULL;
	int count = 0;
589
	int timeout;
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	if (!(local->hw.flags & IEEE80211_HW_SUPPORTS_PS)) {
		local->ps_sdata = NULL;
		return;
	}

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	if (!list_empty(&local->work_list)) {
		local->ps_sdata = NULL;
		goto change;
	}

601
	list_for_each_entry(sdata, &local->interfaces, list) {
602
		if (!ieee80211_sdata_running(sdata))
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			continue;
		if (sdata->vif.type != NL80211_IFTYPE_STATION)
			continue;
		found = sdata;
		count++;
	}

610
	if (count == 1 && found->u.mgd.powersave &&
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	    found->u.mgd.associated &&
612
	    found->u.mgd.associated->beacon_ies &&
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	    !(found->u.mgd.flags & (IEEE80211_STA_BEACON_POLL |
				    IEEE80211_STA_CONNECTION_POLL))) {
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		struct ieee80211_conf *conf = &local->hw.conf;
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		s32 beaconint_us;

		if (latency < 0)
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			latency = pm_qos_request(PM_QOS_NETWORK_LATENCY);
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		beaconint_us = ieee80211_tu_to_usec(
					found->vif.bss_conf.beacon_int);

624
		timeout = local->dynamic_ps_forced_timeout;
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		if (timeout < 0) {
			/*
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			 * Go to full PSM if the user configures a very low
			 * latency requirement.
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			 * The 2000 second value is there for compatibility
			 * until the PM_QOS_NETWORK_LATENCY is configured
			 * with real values.
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			 */
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			if (latency > (1900 * USEC_PER_MSEC) &&
			    latency != (2000 * USEC_PER_SEC))
635
				timeout = 0;
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			else
				timeout = 100;
638
		}
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		local->dynamic_ps_user_timeout = timeout;
		if (!local->disable_dynamic_ps)
			conf->dynamic_ps_timeout =
				local->dynamic_ps_user_timeout;
643

644
		if (beaconint_us > latency) {
645
			local->ps_sdata = NULL;
646
		} else {
647
			struct ieee80211_bss *bss;
648
			int maxslp = 1;
649
			u8 dtimper;
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			bss = (void *)found->u.mgd.associated->priv;
			dtimper = bss->dtim_period;

			/* If the TIM IE is invalid, pretend the value is 1 */
			if (!dtimper)
				dtimper = 1;
			else if (dtimper > 1)
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				maxslp = min_t(int, dtimper,
						    latency / beaconint_us);

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			local->hw.conf.max_sleep_period = maxslp;
662
			local->hw.conf.ps_dtim_period = dtimper;
663
			local->ps_sdata = found;
664
		}
665
	} else {
666
		local->ps_sdata = NULL;
667
	}
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 change:
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	ieee80211_change_ps(local);
}

void ieee80211_dynamic_ps_disable_work(struct work_struct *work)
{
	struct ieee80211_local *local =
		container_of(work, struct ieee80211_local,
			     dynamic_ps_disable_work);

	if (local->hw.conf.flags & IEEE80211_CONF_PS) {
		local->hw.conf.flags &= ~IEEE80211_CONF_PS;
		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
	}

	ieee80211_wake_queues_by_reason(&local->hw,
					IEEE80211_QUEUE_STOP_REASON_PS);
}

void ieee80211_dynamic_ps_enable_work(struct work_struct *work)
{
	struct ieee80211_local *local =
		container_of(work, struct ieee80211_local,
			     dynamic_ps_enable_work);
	struct ieee80211_sub_if_data *sdata = local->ps_sdata;
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	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
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	/* can only happen when PS was just disabled anyway */
	if (!sdata)
		return;

	if (local->hw.conf.flags & IEEE80211_CONF_PS)
		return;

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	if ((local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK) &&
	    (!(ifmgd->flags & IEEE80211_STA_NULLFUNC_ACKED)))
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		ieee80211_send_nullfunc(local, sdata, 1);

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	if (!((local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS) &&
	      (local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK)) ||
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	    (ifmgd->flags & IEEE80211_STA_NULLFUNC_ACKED)) {
		ifmgd->flags &= ~IEEE80211_STA_NULLFUNC_ACKED;
		local->hw.conf.flags |= IEEE80211_CONF_PS;
		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
	}
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}

void ieee80211_dynamic_ps_timer(unsigned long data)
{
	struct ieee80211_local *local = (void *) data;

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	if (local->quiescing || local->suspended)
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		return;

723
	ieee80211_queue_work(&local->hw, &local->dynamic_ps_enable_work);
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}

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/* MLME */
727
static void ieee80211_sta_wmm_params(struct ieee80211_local *local,
728
				     struct ieee80211_sub_if_data *sdata,
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				     u8 *wmm_param, size_t wmm_param_len)
{
	struct ieee80211_tx_queue_params params;
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	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
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	size_t left;
	int count;
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	u8 *pos, uapsd_queues = 0;
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	if (!local->ops->conf_tx)
		return;

740
	if (local->hw.queues < 4)
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		return;

	if (!wmm_param)
		return;

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	if (wmm_param_len < 8 || wmm_param[5] /* version */ != 1)
		return;
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	if (ifmgd->flags & IEEE80211_STA_UAPSD_ENABLED)
750
		uapsd_queues = local->uapsd_queues;
751

752
	count = wmm_param[6] & 0x0f;
753
	if (count == ifmgd->wmm_last_param_set)
754
		return;
755
	ifmgd->wmm_last_param_set = count;
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	pos = wmm_param + 8;
	left = wmm_param_len - 8;

	memset(&params, 0, sizeof(params));

	local->wmm_acm = 0;
	for (; left >= 4; left -= 4, pos += 4) {
		int aci = (pos[0] >> 5) & 0x03;
		int acm = (pos[0] >> 4) & 0x01;
766
		bool uapsd = false;
767 768 769
		int queue;

		switch (aci) {
770
		case 1: /* AC_BK */
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			queue = 3;
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			if (acm)
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				local->wmm_acm |= BIT(1) | BIT(2); /* BK/- */
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			if (uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_BK)
				uapsd = true;
776
			break;
777
		case 2: /* AC_VI */
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			queue = 1;
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			if (acm)
780
				local->wmm_acm |= BIT(4) | BIT(5); /* CL/VI */
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			if (uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_VI)
				uapsd = true;
783
			break;
784
		case 3: /* AC_VO */
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			queue = 0;
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			if (acm)
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				local->wmm_acm |= BIT(6) | BIT(7); /* VO/NC */
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			if (uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_VO)
				uapsd = true;
790
			break;
791
		case 0: /* AC_BE */
792
		default:
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			queue = 2;
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			if (acm)
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				local->wmm_acm |= BIT(0) | BIT(3); /* BE/EE */
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			if (uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_BE)
				uapsd = true;
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			break;
		}

		params.aifs = pos[0] & 0x0f;
		params.cw_max = ecw2cw((pos[1] & 0xf0) >> 4);
		params.cw_min = ecw2cw(pos[1] & 0x0f);
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		params.txop = get_unaligned_le16(pos + 2);
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		params.uapsd = uapsd;

807
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
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		wiphy_debug(local->hw.wiphy,
			    "WMM queue=%d aci=%d acm=%d aifs=%d "
			    "cWmin=%d cWmax=%d txop=%d uapsd=%d\n",
			    queue, aci, acm,
			    params.aifs, params.cw_min, params.cw_max,
			    params.txop, params.uapsd);
814
#endif
815
		if (drv_conf_tx(local, queue, &params))
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			wiphy_debug(local->hw.wiphy,
				    "failed to set TX queue parameters for queue %d\n",
				    queue);
819
	}
820 821

	/* enable WMM or activate new settings */
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	sdata->vif.bss_conf.qos = true;
	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_QOS);
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}

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static u32 ieee80211_handle_bss_capability(struct ieee80211_sub_if_data *sdata,
					   u16 capab, bool erp_valid, u8 erp)
828
{
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	struct ieee80211_bss_conf *bss_conf = &sdata->vif.bss_conf;
830
	u32 changed = 0;
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	bool use_protection;
	bool use_short_preamble;
	bool use_short_slot;

	if (erp_valid) {
		use_protection = (erp & WLAN_ERP_USE_PROTECTION) != 0;
		use_short_preamble = (erp & WLAN_ERP_BARKER_PREAMBLE) == 0;
	} else {
		use_protection = false;
		use_short_preamble = !!(capab & WLAN_CAPABILITY_SHORT_PREAMBLE);
	}

	use_short_slot = !!(capab & WLAN_CAPABILITY_SHORT_SLOT_TIME);
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	if (sdata->local->hw.conf.channel->band == IEEE80211_BAND_5GHZ)
		use_short_slot = true;
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	if (use_protection != bss_conf->use_cts_prot) {
		bss_conf->use_cts_prot = use_protection;
		changed |= BSS_CHANGED_ERP_CTS_PROT;
850
	}
851

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	if (use_short_preamble != bss_conf->use_short_preamble) {
		bss_conf->use_short_preamble = use_short_preamble;
854
		changed |= BSS_CHANGED_ERP_PREAMBLE;
855
	}
856

857 858 859
	if (use_short_slot != bss_conf->use_short_slot) {
		bss_conf->use_short_slot = use_short_slot;
		changed |= BSS_CHANGED_ERP_SLOT;
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	}

	return changed;
}

865
static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata,
866
				     struct cfg80211_bss *cbss,
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				     u32 bss_info_changed)
868
{
869
	struct ieee80211_bss *bss = (void *)cbss->priv;
870
	struct ieee80211_local *local = sdata->local;
871
	struct ieee80211_bss_conf *bss_conf = &sdata->vif.bss_conf;
872

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	bss_info_changed |= BSS_CHANGED_ASSOC;
874
	/* set timing information */
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	bss_conf->beacon_int = cbss->beacon_interval;
	bss_conf->timestamp = cbss->tsf;
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	bss_info_changed |= BSS_CHANGED_BEACON_INT;
	bss_info_changed |= ieee80211_handle_bss_capability(sdata,
880
		cbss->capability, bss->has_erp_value, bss->erp_value);
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	sdata->u.mgd.beacon_timeout = usecs_to_jiffies(ieee80211_tu_to_usec(
		IEEE80211_BEACON_LOSS_COUNT * bss_conf->beacon_int));

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	sdata->u.mgd.associated = cbss;
	memcpy(sdata->u.mgd.bssid, cbss->bssid, ETH_ALEN);
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	sdata->u.mgd.flags |= IEEE80211_STA_RESET_SIGNAL_AVE;

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	/* just to be sure */
	sdata->u.mgd.flags &= ~(IEEE80211_STA_CONNECTION_POLL |
				IEEE80211_STA_BEACON_POLL);

894
	ieee80211_led_assoc(local, 1);
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	if (local->hw.flags & IEEE80211_HW_NEED_DTIM_PERIOD)
		bss_conf->dtim_period = bss->dtim_period;
	else
		bss_conf->dtim_period = 0;

901
	bss_conf->assoc = 1;
902 903 904 905 906
	/*
	 * For now just always ask the driver to update the basic rateset
	 * when we have associated, we aren't checking whether it actually
	 * changed or not.
	 */
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	bss_info_changed |= BSS_CHANGED_BASIC_RATES;
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	/* And the BSSID changed - we're associated now */
	bss_info_changed |= BSS_CHANGED_BSSID;

912 913
	/* Tell the driver to monitor connection quality (if supported) */
	if ((local->hw.flags & IEEE80211_HW_SUPPORTS_CQM_RSSI) &&
914
	    bss_conf->cqm_rssi_thold)
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		bss_info_changed |= BSS_CHANGED_CQM;

917 918 919 920 921 922
	/* Enable ARP filtering */
	if (bss_conf->arp_filter_enabled != sdata->arp_filter_state) {
		bss_conf->arp_filter_enabled = sdata->arp_filter_state;
		bss_info_changed |= BSS_CHANGED_ARP_FILTER;
	}

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	ieee80211_bss_info_change_notify(sdata, bss_info_changed);
924

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	mutex_lock(&local->iflist_mtx);
	ieee80211_recalc_ps(local, -1);
927
	ieee80211_recalc_smps(local);
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928
	mutex_unlock(&local->iflist_mtx);
929

930
	netif_tx_start_all_queues(sdata->dev);
931
	netif_carrier_on(sdata->dev);
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}

934
static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
935
				   bool remove_sta, bool tx)
936
{
937
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
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	struct ieee80211_local *local = sdata->local;
	struct sta_info *sta;
940
	u32 changed = 0, config_changed = 0;
941
	u8 bssid[ETH_ALEN];
942

943 944
	ASSERT_MGD_MTX(ifmgd);

945 946 947
	if (WARN_ON(!ifmgd->associated))
		return;

948
	memcpy(bssid, ifmgd->associated->bssid, ETH_ALEN);
949

950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965
	ifmgd->associated = NULL;
	memset(ifmgd->bssid, 0, ETH_ALEN);

	/*
	 * we need to commit the associated = NULL change because the
	 * scan code uses that to determine whether this iface should
	 * go to/wake up from powersave or not -- and could otherwise
	 * wake the queues erroneously.
	 */
	smp_mb();

	/*
	 * Thus, we can only afterwards stop the queues -- to account
	 * for the case where another CPU is finishing a scan at this
	 * time -- we don't want the scan code to enable queues.
	 */
966

967
	netif_tx_stop_all_queues(sdata->dev);
968 969
	netif_carrier_off(sdata->dev);

970
	mutex_lock(&local->sta_mtx);
971
	sta = sta_info_get(sdata, bssid);
972
	if (sta) {
973
		set_sta_flags(sta, WLAN_STA_BLOCK_BA);
974
		ieee80211_sta_tear_down_BA_sessions(sta, tx);
975
	}
976
	mutex_unlock(&local->sta_mtx);
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978 979 980
	changed |= ieee80211_reset_erp_info(sdata);

	ieee80211_led_assoc(local, 0);
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	changed |= BSS_CHANGED_ASSOC;
	sdata->vif.bss_conf.assoc = false;
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984 985
	ieee80211_set_wmm_default(sdata);

986
	/* channel(_type) changes are handled by ieee80211_hw_config */
987
	WARN_ON(!ieee80211_set_channel_type(local, sdata, NL80211_CHAN_NO_HT));
988

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	/* on the next assoc, re-program HT parameters */
	sdata->ht_opmode_valid = false;

992 993
	local->power_constr_level = 0;

994 995 996
	del_timer_sync(&local->dynamic_ps_timer);
	cancel_work_sync(&local->dynamic_ps_enable_work);

997 998 999 1000
	if (local->hw.conf.flags & IEEE80211_CONF_PS) {
		local->hw.conf.flags &= ~IEEE80211_CONF_PS;
		config_changed |= IEEE80211_CONF_CHANGE_PS;
	}
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1001

1002
	ieee80211_hw_config(local, config_changed);
1003

1004 1005 1006 1007 1008 1009
	/* Disable ARP filtering */
	if (sdata->vif.bss_conf.arp_filter_enabled) {
		sdata->vif.bss_conf.arp_filter_enabled = false;
		changed |= BSS_CHANGED_ARP_FILTER;
	}

1010 1011
	/* The BSSID (not really interesting) and HT changed */
	changed |= BSS_CHANGED_BSSID | BSS_CHANGED_HT;
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	ieee80211_bss_info_change_notify(sdata, changed);
1013

1014 1015
	if (remove_sta)
		sta_info_destroy_addr(sdata, bssid);
1016 1017 1018 1019 1020

	del_timer_sync(&sdata->u.mgd.conn_mon_timer);
	del_timer_sync(&sdata->u.mgd.bcn_mon_timer);
	del_timer_sync(&sdata->u.mgd.timer);
	del_timer_sync(&sdata->u.mgd.chswitch_timer);
1021
}
1022

1023 1024 1025 1026 1027 1028 1029 1030
void ieee80211_sta_rx_notify(struct ieee80211_sub_if_data *sdata,
			     struct ieee80211_hdr *hdr)
{
	/*
	 * We can postpone the mgd.timer whenever receiving unicast frames
	 * from AP because we know that the connection is working both ways
	 * at that time. But multicast frames (and hence also beacons) must
	 * be ignored here, because we need to trigger the timer during
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	 * data idle periods for sending the periodic probe request to the
	 * AP we're connected to.
1033
	 */
1034 1035 1036
	if (is_multicast_ether_addr(hdr->addr1))
		return;

1037
	ieee80211_sta_reset_conn_monitor(sdata);
1038
}
1039

1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069
static void ieee80211_reset_ap_probe(struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;

	if (!(ifmgd->flags & (IEEE80211_STA_BEACON_POLL |
			      IEEE80211_STA_CONNECTION_POLL)))
	    return;

	ifmgd->flags &= ~(IEEE80211_STA_CONNECTION_POLL |
			  IEEE80211_STA_BEACON_POLL);
	mutex_lock(&sdata->local->iflist_mtx);
	ieee80211_recalc_ps(sdata->local, -1);
	mutex_unlock(&sdata->local->iflist_mtx);

	if (sdata->local->hw.flags & IEEE80211_HW_CONNECTION_MONITOR)
		return;

	/*
	 * We've received a probe response, but are not sure whether
	 * we have or will be receiving any beacons or data, so let's
	 * schedule the timers again, just in case.
	 */
	ieee80211_sta_reset_beacon_monitor(sdata);

	mod_timer(&ifmgd->conn_mon_timer,
		  round_jiffies_up(jiffies +
				   IEEE80211_CONNECTION_IDLE_TIME));
}

void ieee80211_sta_tx_notify(struct ieee80211_sub_if_data *sdata,
1070
			     struct ieee80211_hdr *hdr, bool ack)
1071
{
1072
	if (!ieee80211_is_data(hdr->frame_control))
1073 1074
	    return;

1075 1076
	if (ack)
		ieee80211_sta_reset_conn_monitor(sdata);
1077 1078 1079

	if (ieee80211_is_nullfunc(hdr->frame_control) &&
	    sdata->u.mgd.probe_send_count > 0) {
1080 1081 1082 1083
		if (ack)
			sdata->u.mgd.probe_send_count = 0;
		else
			sdata->u.mgd.nullfunc_failed = true;
1084 1085 1086 1087
		ieee80211_queue_work(&sdata->local->hw, &sdata->work);
	}
}

1088 1089 1090 1091
static void ieee80211_mgd_probe_ap_send(struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	const u8 *ssid;
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	u8 *dst = ifmgd->associated->bssid;
	u8 unicast_limit = max(1, IEEE80211_MAX_PROBE_TRIES - 3);

	/*
	 * Try sending broadcast probe requests for the last three
	 * probe requests after the first ones failed since some
	 * buggy APs only support broadcast probe requests.
	 */
	if (ifmgd->probe_send_count >= unicast_limit)
		dst = NULL;
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1103 1104 1105 1106 1107 1108 1109
	/*
	 * When the hardware reports an accurate Tx ACK status, it's
	 * better to send a nullfunc frame instead of a probe request,
	 * as it will kick us off the AP quickly if we aren't associated
	 * anymore. The timeout will be reset if the frame is ACKed by
	 * the AP.
	 */
1110 1111
	if (sdata->local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS) {
		ifmgd->nullfunc_failed = false;
1112
		ieee80211_send_nullfunc(sdata->local, sdata, 0);
1113
	} else {
1114 1115 1116
		ssid = ieee80211_bss_get_ie(ifmgd->associated, WLAN_EID_SSID);
		ieee80211_send_probe_req(sdata, dst, ssid + 2, ssid[1], NULL, 0);
	}
1117 1118 1119 1120 1121 1122

	ifmgd->probe_send_count++;
	ifmgd->probe_timeout = jiffies + IEEE80211_PROBE_WAIT;
	run_again(ifmgd, ifmgd->probe_timeout);
}

1123 1124
static void ieee80211_mgd_probe_ap(struct ieee80211_sub_if_data *sdata,
				   bool beacon)
1125 1126
{
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
1127
	bool already = false;
1128

1129
	if (!ieee80211_sdata_running(sdata))
1130 1131
		return;

1132 1133 1134
	if (sdata->local->scanning)
		return;

1135 1136 1137
	if (sdata->local->tmp_channel)
		return;

1138 1139 1140 1141 1142
	mutex_lock(&ifmgd->mtx);

	if (!ifmgd->associated)
		goto out;

1143
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1144 1145
	if (beacon && net_ratelimit())
		printk(KERN_DEBUG "%s: detected beacon loss from AP "
1146
		       "- sending probe request\n", sdata->name);
1147
#endif
1148

1149 1150 1151