rx.c 57.3 KB
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/*
 * Copyright 2002-2005, Instant802 Networks, Inc.
 * Copyright 2005-2006, Devicescape Software, Inc.
 * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
 * Copyright 2007	Johannes Berg <johannes@sipsolutions.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.
 */

#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
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#include <linux/rcupdate.h>
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#include <net/mac80211.h>
#include <net/ieee80211_radiotap.h>

#include "ieee80211_i.h"
#include "ieee80211_led.h"
#include "wep.h"
#include "wpa.h"
#include "tkip.h"
#include "wme.h"

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u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
				struct tid_ampdu_rx *tid_agg_rx,
				struct sk_buff *skb, u16 mpdu_seq_num,
				int bar_req);
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/*
 * monitor mode reception
 *
 * This function cleans up the SKB, i.e. it removes all the stuff
 * only useful for monitoring.
 */
static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
					   struct sk_buff *skb,
					   int rtap_len)
{
	skb_pull(skb, rtap_len);

	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
		if (likely(skb->len > FCS_LEN))
			skb_trim(skb, skb->len - FCS_LEN);
		else {
			/* driver bug */
			WARN_ON(1);
			dev_kfree_skb(skb);
			skb = NULL;
		}
	}

	return skb;
}

static inline int should_drop_frame(struct ieee80211_rx_status *status,
				    struct sk_buff *skb,
				    int present_fcs_len,
				    int radiotap_len)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;

	if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
		return 1;
	if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
		return 1;
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	if (((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_FTYPE)) ==
			cpu_to_le16(IEEE80211_FTYPE_CTL)) &&
	    ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE)) !=
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			cpu_to_le16(IEEE80211_STYPE_PSPOLL)) &&
	    ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE)) !=
			cpu_to_le16(IEEE80211_STYPE_BACK_REQ)))
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		return 1;
	return 0;
}

/*
 * This function copies a received frame to all monitor interfaces and
 * returns a cleaned-up SKB that no longer includes the FCS nor the
 * radiotap header the driver might have added.
 */
static struct sk_buff *
ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
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		     struct ieee80211_rx_status *status,
		     struct ieee80211_rate *rate)
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{
	struct ieee80211_sub_if_data *sdata;
	int needed_headroom = 0;
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	struct ieee80211_radiotap_header *rthdr;
	__le64 *rttsft = NULL;
	struct ieee80211_rtap_fixed_data {
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		u8 flags;
		u8 rate;
		__le16 chan_freq;
		__le16 chan_flags;
		u8 antsignal;
		u8 padding_for_rxflags;
		__le16 rx_flags;
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	} __attribute__ ((packed)) *rtfixed;
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	struct sk_buff *skb, *skb2;
	struct net_device *prev_dev = NULL;
	int present_fcs_len = 0;
	int rtap_len = 0;

	/*
	 * First, we may need to make a copy of the skb because
	 *  (1) we need to modify it for radiotap (if not present), and
	 *  (2) the other RX handlers will modify the skb we got.
	 *
	 * We don't need to, of course, if we aren't going to return
	 * the SKB because it has a bad FCS/PLCP checksum.
	 */
	if (status->flag & RX_FLAG_RADIOTAP)
		rtap_len = ieee80211_get_radiotap_len(origskb->data);
	else
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		/* room for radiotap header, always present fields and TSFT */
		needed_headroom = sizeof(*rthdr) + sizeof(*rtfixed) + 8;
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	if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
		present_fcs_len = FCS_LEN;

	if (!local->monitors) {
		if (should_drop_frame(status, origskb, present_fcs_len,
				      rtap_len)) {
			dev_kfree_skb(origskb);
			return NULL;
		}

		return remove_monitor_info(local, origskb, rtap_len);
	}

	if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
		/* only need to expand headroom if necessary */
		skb = origskb;
		origskb = NULL;

		/*
		 * This shouldn't trigger often because most devices have an
		 * RX header they pull before we get here, and that should
		 * be big enough for our radiotap information. We should
		 * probably export the length to drivers so that we can have
		 * them allocate enough headroom to start with.
		 */
		if (skb_headroom(skb) < needed_headroom &&
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		    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
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			dev_kfree_skb(skb);
			return NULL;
		}
	} else {
		/*
		 * Need to make a copy and possibly remove radiotap header
		 * and FCS from the original.
		 */
		skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);

		origskb = remove_monitor_info(local, origskb, rtap_len);

		if (!skb)
			return origskb;
	}

	/* if necessary, prepend radiotap information */
	if (!(status->flag & RX_FLAG_RADIOTAP)) {
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		rtfixed = (void *) skb_push(skb, sizeof(*rtfixed));
		rtap_len = sizeof(*rthdr) + sizeof(*rtfixed);
		if (status->flag & RX_FLAG_TSFT) {
			rttsft = (void *) skb_push(skb, sizeof(*rttsft));
			rtap_len += 8;
		}
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		rthdr = (void *) skb_push(skb, sizeof(*rthdr));
		memset(rthdr, 0, sizeof(*rthdr));
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		memset(rtfixed, 0, sizeof(*rtfixed));
		rthdr->it_present =
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			cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
				    (1 << IEEE80211_RADIOTAP_RATE) |
				    (1 << IEEE80211_RADIOTAP_CHANNEL) |
				    (1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL) |
				    (1 << IEEE80211_RADIOTAP_RX_FLAGS));
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		rtfixed->flags = 0;
		if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
			rtfixed->flags |= IEEE80211_RADIOTAP_F_FCS;

		if (rttsft) {
			*rttsft = cpu_to_le64(status->mactime);
			rthdr->it_present |=
				cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
		}
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		/* FIXME: when radiotap gets a 'bad PLCP' flag use it here */
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		rtfixed->rx_flags = 0;
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		if (status->flag &
		    (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
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			rtfixed->rx_flags |=
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				cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS);

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		rtfixed->rate = rate->bitrate / 5;
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		rtfixed->chan_freq = cpu_to_le16(status->freq);
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		if (status->band == IEEE80211_BAND_5GHZ)
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			rtfixed->chan_flags =
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				cpu_to_le16(IEEE80211_CHAN_OFDM |
					    IEEE80211_CHAN_5GHZ);
		else
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			rtfixed->chan_flags =
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				cpu_to_le16(IEEE80211_CHAN_DYN |
					    IEEE80211_CHAN_2GHZ);

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		rtfixed->antsignal = status->ssi;
		rthdr->it_len = cpu_to_le16(rtap_len);
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	}

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	skb_reset_mac_header(skb);
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	skb->ip_summed = CHECKSUM_UNNECESSARY;
	skb->pkt_type = PACKET_OTHERHOST;
	skb->protocol = htons(ETH_P_802_2);

	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
		if (!netif_running(sdata->dev))
			continue;

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		if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR)
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			continue;

		if (prev_dev) {
			skb2 = skb_clone(skb, GFP_ATOMIC);
			if (skb2) {
				skb2->dev = prev_dev;
				netif_rx(skb2);
			}
		}

		prev_dev = sdata->dev;
		sdata->dev->stats.rx_packets++;
		sdata->dev->stats.rx_bytes += skb->len;
	}

	if (prev_dev) {
		skb->dev = prev_dev;
		netif_rx(skb);
	} else
		dev_kfree_skb(skb);

	return origskb;
}


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static void ieee80211_parse_qos(struct ieee80211_txrx_data *rx)
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{
	u8 *data = rx->skb->data;
	int tid;

	/* does the frame have a qos control field? */
	if (WLAN_FC_IS_QOS_DATA(rx->fc)) {
		u8 *qc = data + ieee80211_get_hdrlen(rx->fc) - QOS_CONTROL_LEN;
		/* frame has qos control */
		tid = qc[0] & QOS_CONTROL_TID_MASK;
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		if (qc[0] & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
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			rx->flags |= IEEE80211_TXRXD_RX_AMSDU;
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		else
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			rx->flags &= ~IEEE80211_TXRXD_RX_AMSDU;
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	} else {
		if (unlikely((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT)) {
			/* Separate TID for management frames */
			tid = NUM_RX_DATA_QUEUES - 1;
		} else {
			/* no qos control present */
			tid = 0; /* 802.1d - Best Effort */
		}
	}
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	I802_DEBUG_INC(rx->local->wme_rx_queue[tid]);
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	/* only a debug counter, sta might not be assigned properly yet */
	if (rx->sta)
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		I802_DEBUG_INC(rx->sta->wme_rx_queue[tid]);

	rx->u.rx.queue = tid;
	/* Set skb->priority to 1d tag if highest order bit of TID is not set.
	 * For now, set skb->priority to 0 for other cases. */
	rx->skb->priority = (tid > 7) ? 0 : tid;
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}
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static void ieee80211_verify_ip_alignment(struct ieee80211_txrx_data *rx)
{
#ifdef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
	int hdrlen;

	if (!WLAN_FC_DATA_PRESENT(rx->fc))
		return;

	/*
	 * Drivers are required to align the payload data in a way that
	 * guarantees that the contained IP header is aligned to a four-
	 * byte boundary. In the case of regular frames, this simply means
	 * aligning the payload to a four-byte boundary (because either
	 * the IP header is directly contained, or IV/RFC1042 headers that
	 * have a length divisible by four are in front of it.
	 *
	 * With A-MSDU frames, however, the payload data address must
	 * yield two modulo four because there are 14-byte 802.3 headers
	 * within the A-MSDU frames that push the IP header further back
	 * to a multiple of four again. Thankfully, the specs were sane
	 * enough this time around to require padding each A-MSDU subframe
	 * to a length that is a multiple of four.
	 *
	 * Padding like atheros hardware adds which is inbetween the 802.11
	 * header and the payload is not supported, the driver is required
	 * to move the 802.11 header further back in that case.
	 */
	hdrlen = ieee80211_get_hdrlen(rx->fc);
	if (rx->flags & IEEE80211_TXRXD_RX_AMSDU)
		hdrlen += ETH_HLEN;
	WARN_ON_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3);
#endif
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}

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static u32 ieee80211_rx_load_stats(struct ieee80211_local *local,
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				   struct sk_buff *skb,
				   struct ieee80211_rx_status *status,
				   struct ieee80211_rate *rate)
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{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
	u32 load = 0, hdrtime;

	/* Estimate total channel use caused by this frame */

	/* 1 bit at 1 Mbit/s takes 1 usec; in channel_use values,
	 * 1 usec = 1/8 * (1080 / 10) = 13.5 */

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	if (status->band == IEEE80211_BAND_5GHZ ||
	    (status->band == IEEE80211_BAND_5GHZ &&
	     rate->flags & IEEE80211_RATE_ERP_G))
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		hdrtime = CHAN_UTIL_HDR_SHORT;
	else
		hdrtime = CHAN_UTIL_HDR_LONG;

	load = hdrtime;
	if (!is_multicast_ether_addr(hdr->addr1))
		load += hdrtime;

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	/* TODO: optimise again */
	load += skb->len * CHAN_UTIL_RATE_LCM / rate->bitrate;
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	/* Divide channel_use by 8 to avoid wrapping around the counter */
	load >>= CHAN_UTIL_SHIFT;

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	return load;
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}

/* rx handlers */

static ieee80211_txrx_result
ieee80211_rx_h_if_stats(struct ieee80211_txrx_data *rx)
{
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	if (rx->sta)
		rx->sta->channel_use_raw += rx->u.rx.load;
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	rx->sdata->channel_use_raw += rx->u.rx.load;
	return TXRX_CONTINUE;
}

static ieee80211_txrx_result
ieee80211_rx_h_passive_scan(struct ieee80211_txrx_data *rx)
{
	struct ieee80211_local *local = rx->local;
	struct sk_buff *skb = rx->skb;

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	if (unlikely(local->sta_hw_scanning))
		return ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status);

	if (unlikely(local->sta_sw_scanning)) {
		/* drop all the other packets during a software scan anyway */
		if (ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status)
		    != TXRX_QUEUED)
			dev_kfree_skb(skb);
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		return TXRX_QUEUED;
	}

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	if (unlikely(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) {
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		/* scanning finished during invoking of handlers */
		I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
		return TXRX_DROP;
	}

	return TXRX_CONTINUE;
}

static ieee80211_txrx_result
ieee80211_rx_h_check(struct ieee80211_txrx_data *rx)
{
	struct ieee80211_hdr *hdr;
	hdr = (struct ieee80211_hdr *) rx->skb->data;

	/* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
	if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
		if (unlikely(rx->fc & IEEE80211_FCTL_RETRY &&
			     rx->sta->last_seq_ctrl[rx->u.rx.queue] ==
			     hdr->seq_ctrl)) {
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			if (rx->flags & IEEE80211_TXRXD_RXRA_MATCH) {
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				rx->local->dot11FrameDuplicateCount++;
				rx->sta->num_duplicates++;
			}
			return TXRX_DROP;
		} else
			rx->sta->last_seq_ctrl[rx->u.rx.queue] = hdr->seq_ctrl;
	}

	if (unlikely(rx->skb->len < 16)) {
		I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
		return TXRX_DROP;
	}

	/* Drop disallowed frame classes based on STA auth/assoc state;
	 * IEEE 802.11, Chap 5.5.
	 *
	 * 80211.o does filtering only based on association state, i.e., it
	 * drops Class 3 frames from not associated stations. hostapd sends
	 * deauth/disassoc frames when needed. In addition, hostapd is
	 * responsible for filtering on both auth and assoc states.
	 */
	if (unlikely(((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA ||
		      ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL &&
		       (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)) &&
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		     rx->sdata->vif.type != IEEE80211_IF_TYPE_IBSS &&
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		     (!rx->sta || !(rx->sta->flags & WLAN_STA_ASSOC)))) {
		if ((!(rx->fc & IEEE80211_FCTL_FROMDS) &&
		     !(rx->fc & IEEE80211_FCTL_TODS) &&
		     (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)
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		    || !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
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			/* Drop IBSS frames and frames for other hosts
			 * silently. */
			return TXRX_DROP;
		}

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		return TXRX_DROP;
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	}

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	return TXRX_CONTINUE;
}


static ieee80211_txrx_result
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ieee80211_rx_h_decrypt(struct ieee80211_txrx_data *rx)
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{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
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	int keyidx;
	int hdrlen;
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	ieee80211_txrx_result result = TXRX_DROP;
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	struct ieee80211_key *stakey = NULL;
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	/*
	 * Key selection 101
	 *
	 * There are three types of keys:
	 *  - GTK (group keys)
	 *  - PTK (pairwise keys)
	 *  - STK (station-to-station pairwise keys)
	 *
	 * When selecting a key, we have to distinguish between multicast
	 * (including broadcast) and unicast frames, the latter can only
	 * use PTKs and STKs while the former always use GTKs. Unless, of
	 * course, actual WEP keys ("pre-RSNA") are used, then unicast
	 * frames can also use key indizes like GTKs. Hence, if we don't
	 * have a PTK/STK we check the key index for a WEP key.
	 *
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	 * Note that in a regular BSS, multicast frames are sent by the
	 * AP only, associated stations unicast the frame to the AP first
	 * which then multicasts it on their behalf.
	 *
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	 * There is also a slight problem in IBSS mode: GTKs are negotiated
	 * with each station, that is something we don't currently handle.
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	 * The spec seems to expect that one negotiates the same key with
	 * every station but there's no such requirement; VLANs could be
	 * possible.
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	 */

	if (!(rx->fc & IEEE80211_FCTL_PROTECTED))
		return TXRX_CONTINUE;
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	/*
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	 * No point in finding a key and decrypting if the frame is neither
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	 * addressed to us nor a multicast frame.
	 */
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	if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
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		return TXRX_CONTINUE;

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	if (rx->sta)
		stakey = rcu_dereference(rx->sta->key);

	if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
		rx->key = stakey;
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	} else {
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		/*
		 * The device doesn't give us the IV so we won't be
		 * able to look up the key. That's ok though, we
		 * don't need to decrypt the frame, we just won't
		 * be able to keep statistics accurate.
		 * Except for key threshold notifications, should
		 * we somehow allow the driver to tell us which key
		 * the hardware used if this flag is set?
		 */
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		if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
		    (rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED))
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			return TXRX_CONTINUE;

		hdrlen = ieee80211_get_hdrlen(rx->fc);

		if (rx->skb->len < 8 + hdrlen)
			return TXRX_DROP; /* TODO: count this? */

		/*
		 * no need to call ieee80211_wep_get_keyidx,
		 * it verifies a bunch of things we've done already
		 */
		keyidx = rx->skb->data[hdrlen + 3] >> 6;

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		rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
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		/*
		 * RSNA-protected unicast frames should always be sent with
		 * pairwise or station-to-station keys, but for WEP we allow
		 * using a key index as well.
		 */
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		if (rx->key && rx->key->conf.alg != ALG_WEP &&
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		    !is_multicast_ether_addr(hdr->addr1))
			rx->key = NULL;
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	}

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	if (rx->key) {
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		rx->key->tx_rx_count++;
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		/* TODO: add threshold stuff again */
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	} else {
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#ifdef CONFIG_MAC80211_DEBUG
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		if (net_ratelimit())
			printk(KERN_DEBUG "%s: RX protected frame,"
			       " but have no key\n", rx->dev->name);
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#endif /* CONFIG_MAC80211_DEBUG */
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		return TXRX_DROP;
	}

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	/* Check for weak IVs if possible */
	if (rx->sta && rx->key->conf.alg == ALG_WEP &&
	    ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) &&
	    (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED) ||
	     !(rx->u.rx.status->flag & RX_FLAG_DECRYPTED)) &&
	    ieee80211_wep_is_weak_iv(rx->skb, rx->key))
		rx->sta->wep_weak_iv_count++;

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	switch (rx->key->conf.alg) {
	case ALG_WEP:
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		result = ieee80211_crypto_wep_decrypt(rx);
		break;
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	case ALG_TKIP:
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		result = ieee80211_crypto_tkip_decrypt(rx);
		break;
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	case ALG_CCMP:
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		result = ieee80211_crypto_ccmp_decrypt(rx);
		break;
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	}

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	/* either the frame has been decrypted or will be dropped */
	rx->u.rx.status->flag |= RX_FLAG_DECRYPTED;

	return result;
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}

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static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta)
{
	struct ieee80211_sub_if_data *sdata;
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	DECLARE_MAC_BUF(mac);

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	sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);

	if (sdata->bss)
		atomic_inc(&sdata->bss->num_sta_ps);
	sta->flags |= WLAN_STA_PS;
	sta->pspoll = 0;
#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
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	printk(KERN_DEBUG "%s: STA %s aid %d enters power save mode\n",
	       dev->name, print_mac(mac, sta->addr), sta->aid);
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#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
}

static int ap_sta_ps_end(struct net_device *dev, struct sta_info *sta)
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	struct sk_buff *skb;
	int sent = 0;
	struct ieee80211_sub_if_data *sdata;
	struct ieee80211_tx_packet_data *pkt_data;
592
	DECLARE_MAC_BUF(mac);
593 594 595 596 597 598 599 600 601 602 603 604 605

	sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
	if (sdata->bss)
		atomic_dec(&sdata->bss->num_sta_ps);
	sta->flags &= ~(WLAN_STA_PS | WLAN_STA_TIM);
	sta->pspoll = 0;
	if (!skb_queue_empty(&sta->ps_tx_buf)) {
		if (local->ops->set_tim)
			local->ops->set_tim(local_to_hw(local), sta->aid, 0);
		if (sdata->bss)
			bss_tim_clear(local, sdata->bss, sta->aid);
	}
#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
606 607
	printk(KERN_DEBUG "%s: STA %s aid %d exits power save mode\n",
	       dev->name, print_mac(mac, sta->addr), sta->aid);
608 609 610 611 612
#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
	/* Send all buffered frames to the station */
	while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
		pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
		sent++;
613
		pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
614 615 616 617 618 619 620
		dev_queue_xmit(skb);
	}
	while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
		pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
		local->total_ps_buffered--;
		sent++;
#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
621
		printk(KERN_DEBUG "%s: STA %s aid %d send PS frame "
622
		       "since STA not sleeping anymore\n", dev->name,
623
		       print_mac(mac, sta->addr), sta->aid);
624
#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
625
		pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644
		dev_queue_xmit(skb);
	}

	return sent;
}

static ieee80211_txrx_result
ieee80211_rx_h_sta_process(struct ieee80211_txrx_data *rx)
{
	struct sta_info *sta = rx->sta;
	struct net_device *dev = rx->dev;
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;

	if (!sta)
		return TXRX_CONTINUE;

	/* Update last_rx only for IBSS packets which are for the current
	 * BSSID to avoid keeping the current IBSS network alive in cases where
	 * other STAs are using different BSSID. */
645
	if (rx->sdata->vif.type == IEEE80211_IF_TYPE_IBSS) {
646 647
		u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
						IEEE80211_IF_TYPE_IBSS);
648 649 650 651
		if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
			sta->last_rx = jiffies;
	} else
	if (!is_multicast_ether_addr(hdr->addr1) ||
652
	    rx->sdata->vif.type == IEEE80211_IF_TYPE_STA) {
653 654 655 656 657 658 659
		/* Update last_rx only for unicast frames in order to prevent
		 * the Probe Request frames (the only broadcast frames from a
		 * STA in infrastructure mode) from keeping a connection alive.
		 */
		sta->last_rx = jiffies;
	}

660
	if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
661 662 663 664
		return TXRX_CONTINUE;

	sta->rx_fragments++;
	sta->rx_bytes += rx->skb->len;
665 666 667
	sta->last_rssi = rx->u.rx.status->ssi;
	sta->last_signal = rx->u.rx.status->signal;
	sta->last_noise = rx->u.rx.status->noise;
668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710

	if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) {
		/* Change STA power saving mode only in the end of a frame
		 * exchange sequence */
		if ((sta->flags & WLAN_STA_PS) && !(rx->fc & IEEE80211_FCTL_PM))
			rx->u.rx.sent_ps_buffered += ap_sta_ps_end(dev, sta);
		else if (!(sta->flags & WLAN_STA_PS) &&
			 (rx->fc & IEEE80211_FCTL_PM))
			ap_sta_ps_start(dev, sta);
	}

	/* Drop data::nullfunc frames silently, since they are used only to
	 * control station power saving mode. */
	if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
	    (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_NULLFUNC) {
		I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
		/* Update counter and free packet here to avoid counting this
		 * as a dropped packed. */
		sta->rx_packets++;
		dev_kfree_skb(rx->skb);
		return TXRX_QUEUED;
	}

	return TXRX_CONTINUE;
} /* ieee80211_rx_h_sta_process */

static inline struct ieee80211_fragment_entry *
ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
			 unsigned int frag, unsigned int seq, int rx_queue,
			 struct sk_buff **skb)
{
	struct ieee80211_fragment_entry *entry;
	int idx;

	idx = sdata->fragment_next;
	entry = &sdata->fragments[sdata->fragment_next++];
	if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
		sdata->fragment_next = 0;

	if (!skb_queue_empty(&entry->skb_list)) {
#ifdef CONFIG_MAC80211_DEBUG
		struct ieee80211_hdr *hdr =
			(struct ieee80211_hdr *) entry->skb_list.next->data;
711 712
		DECLARE_MAC_BUF(mac);
		DECLARE_MAC_BUF(mac2);
713 714
		printk(KERN_DEBUG "%s: RX reassembly removed oldest "
		       "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
715
		       "addr1=%s addr2=%s\n",
716 717
		       sdata->dev->name, idx,
		       jiffies - entry->first_frag_time, entry->seq,
718 719
		       entry->last_frag, print_mac(mac, hdr->addr1),
		       print_mac(mac2, hdr->addr2));
720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784
#endif /* CONFIG_MAC80211_DEBUG */
		__skb_queue_purge(&entry->skb_list);
	}

	__skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
	*skb = NULL;
	entry->first_frag_time = jiffies;
	entry->seq = seq;
	entry->rx_queue = rx_queue;
	entry->last_frag = frag;
	entry->ccmp = 0;
	entry->extra_len = 0;

	return entry;
}

static inline struct ieee80211_fragment_entry *
ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
			  u16 fc, unsigned int frag, unsigned int seq,
			  int rx_queue, struct ieee80211_hdr *hdr)
{
	struct ieee80211_fragment_entry *entry;
	int i, idx;

	idx = sdata->fragment_next;
	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
		struct ieee80211_hdr *f_hdr;
		u16 f_fc;

		idx--;
		if (idx < 0)
			idx = IEEE80211_FRAGMENT_MAX - 1;

		entry = &sdata->fragments[idx];
		if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
		    entry->rx_queue != rx_queue ||
		    entry->last_frag + 1 != frag)
			continue;

		f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data;
		f_fc = le16_to_cpu(f_hdr->frame_control);

		if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) ||
		    compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
		    compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
			continue;

		if (entry->first_frag_time + 2 * HZ < jiffies) {
			__skb_queue_purge(&entry->skb_list);
			continue;
		}
		return entry;
	}

	return NULL;
}

static ieee80211_txrx_result
ieee80211_rx_h_defragment(struct ieee80211_txrx_data *rx)
{
	struct ieee80211_hdr *hdr;
	u16 sc;
	unsigned int frag, seq;
	struct ieee80211_fragment_entry *entry;
	struct sk_buff *skb;
785
	DECLARE_MAC_BUF(mac);
786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804

	hdr = (struct ieee80211_hdr *) rx->skb->data;
	sc = le16_to_cpu(hdr->seq_ctrl);
	frag = sc & IEEE80211_SCTL_FRAG;

	if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) ||
		   (rx->skb)->len < 24 ||
		   is_multicast_ether_addr(hdr->addr1))) {
		/* not fragmented */
		goto out;
	}
	I802_DEBUG_INC(rx->local->rx_handlers_fragments);

	seq = (sc & IEEE80211_SCTL_SEQ) >> 4;

	if (frag == 0) {
		/* This is the first fragment of a new frame. */
		entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
						 rx->u.rx.queue, &(rx->skb));
805
		if (rx->key && rx->key->conf.alg == ALG_CCMP &&
806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831
		    (rx->fc & IEEE80211_FCTL_PROTECTED)) {
			/* Store CCMP PN so that we can verify that the next
			 * fragment has a sequential PN value. */
			entry->ccmp = 1;
			memcpy(entry->last_pn,
			       rx->key->u.ccmp.rx_pn[rx->u.rx.queue],
			       CCMP_PN_LEN);
		}
		return TXRX_QUEUED;
	}

	/* This is a fragment for a frame that should already be pending in
	 * fragment cache. Add this fragment to the end of the pending entry.
	 */
	entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq,
					  rx->u.rx.queue, hdr);
	if (!entry) {
		I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
		return TXRX_DROP;
	}

	/* Verify that MPDUs within one MSDU have sequential PN values.
	 * (IEEE 802.11i, 8.3.3.4.5) */
	if (entry->ccmp) {
		int i;
		u8 pn[CCMP_PN_LEN], *rpn;
832
		if (!rx->key || rx->key->conf.alg != ALG_CCMP)
833 834 835 836 837 838 839 840 841
			return TXRX_DROP;
		memcpy(pn, entry->last_pn, CCMP_PN_LEN);
		for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
			pn[i]++;
			if (pn[i])
				break;
		}
		rpn = rx->key->u.ccmp.rx_pn[rx->u.rx.queue];
		if (memcmp(pn, rpn, CCMP_PN_LEN) != 0) {
842 843
			if (net_ratelimit())
				printk(KERN_DEBUG "%s: defrag: CCMP PN not "
844
				       "sequential A2=%s"
845 846
				       " PN=%02x%02x%02x%02x%02x%02x "
				       "(expected %02x%02x%02x%02x%02x%02x)\n",
847
				       rx->dev->name, print_mac(mac, hdr->addr2),
848 849 850
				       rpn[0], rpn[1], rpn[2], rpn[3], rpn[4],
				       rpn[5], pn[0], pn[1], pn[2], pn[3],
				       pn[4], pn[5]);
851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880
			return TXRX_DROP;
		}
		memcpy(entry->last_pn, pn, CCMP_PN_LEN);
	}

	skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc));
	__skb_queue_tail(&entry->skb_list, rx->skb);
	entry->last_frag = frag;
	entry->extra_len += rx->skb->len;
	if (rx->fc & IEEE80211_FCTL_MOREFRAGS) {
		rx->skb = NULL;
		return TXRX_QUEUED;
	}

	rx->skb = __skb_dequeue(&entry->skb_list);
	if (skb_tailroom(rx->skb) < entry->extra_len) {
		I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
		if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
					      GFP_ATOMIC))) {
			I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
			__skb_queue_purge(&entry->skb_list);
			return TXRX_DROP;
		}
	}
	while ((skb = __skb_dequeue(&entry->skb_list))) {
		memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
		dev_kfree_skb(skb);
	}

	/* Complete frame has been reassembled - process it now */
881
	rx->flags |= IEEE80211_TXRXD_FRAGMENTED;
882 883 884 885 886 887 888 889 890 891 892 893 894 895

 out:
	if (rx->sta)
		rx->sta->rx_packets++;
	if (is_multicast_ether_addr(hdr->addr1))
		rx->local->dot11MulticastReceivedFrameCount++;
	else
		ieee80211_led_rx(rx->local);
	return TXRX_CONTINUE;
}

static ieee80211_txrx_result
ieee80211_rx_h_ps_poll(struct ieee80211_txrx_data *rx)
{
896
	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
897 898
	struct sk_buff *skb;
	int no_pending_pkts;
899
	DECLARE_MAC_BUF(mac);
900 901 902 903

	if (likely(!rx->sta ||
		   (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL ||
		   (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL ||
904
		   !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)))
905 906
		return TXRX_CONTINUE;

907 908
	if ((sdata->vif.type != IEEE80211_IF_TYPE_AP) &&
	    (sdata->vif.type != IEEE80211_IF_TYPE_VLAN))
909 910
		return TXRX_DROP;

911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928
	skb = skb_dequeue(&rx->sta->tx_filtered);
	if (!skb) {
		skb = skb_dequeue(&rx->sta->ps_tx_buf);
		if (skb)
			rx->local->total_ps_buffered--;
	}
	no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
		skb_queue_empty(&rx->sta->ps_tx_buf);

	if (skb) {
		struct ieee80211_hdr *hdr =
			(struct ieee80211_hdr *) skb->data;

		/* tell TX path to send one frame even though the STA may
		 * still remain is PS mode after this frame exchange */
		rx->sta->pspoll = 1;

#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
929 930
		printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n",
		       print_mac(mac, rx->sta->addr), rx->sta->aid,
931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952
		       skb_queue_len(&rx->sta->ps_tx_buf));
#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */

		/* Use MoreData flag to indicate whether there are more
		 * buffered frames for this STA */
		if (no_pending_pkts) {
			hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
			rx->sta->flags &= ~WLAN_STA_TIM;
		} else
			hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);

		dev_queue_xmit(skb);

		if (no_pending_pkts) {
			if (rx->local->ops->set_tim)
				rx->local->ops->set_tim(local_to_hw(rx->local),
						       rx->sta->aid, 0);
			if (rx->sdata->bss)
				bss_tim_clear(rx->local, rx->sdata->bss, rx->sta->aid);
		}
#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
	} else if (!rx->u.rx.sent_ps_buffered) {
953
		printk(KERN_DEBUG "%s: STA %s sent PS Poll even "
954
		       "though there is no buffered frames for it\n",
955
		       rx->dev->name, print_mac(mac, rx->sta->addr));
956 957 958 959 960 961 962 963 964 965 966
#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */

	}

	/* Free PS Poll skb here instead of returning TXRX_DROP that would
	 * count as an dropped frame. */
	dev_kfree_skb(rx->skb);

	return TXRX_QUEUED;
}

967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986
static ieee80211_txrx_result
ieee80211_rx_h_remove_qos_control(struct ieee80211_txrx_data *rx)
{
	u16 fc = rx->fc;
	u8 *data = rx->skb->data;
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) data;

	if (!WLAN_FC_IS_QOS_DATA(fc))
		return TXRX_CONTINUE;

	/* remove the qos control field, update frame type and meta-data */
	memmove(data + 2, data, ieee80211_get_hdrlen(fc) - 2);
	hdr = (struct ieee80211_hdr *) skb_pull(rx->skb, 2);
	/* change frame type to non QOS */
	rx->fc = fc &= ~IEEE80211_STYPE_QOS_DATA;
	hdr->frame_control = cpu_to_le16(fc);

	return TXRX_CONTINUE;
}

987
static int
988
ieee80211_802_1x_port_control(struct ieee80211_txrx_data *rx)
989
{
990 991
	if (unlikely(rx->sdata->ieee802_1x_pac &&
		     (!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED)))) {
992
#ifdef CONFIG_MAC80211_DEBUG
993 994
		printk(KERN_DEBUG "%s: dropped frame "
		       "(unauthorized port)\n", rx->dev->name);
995
#endif /* CONFIG_MAC80211_DEBUG */
996
		return -EACCES;
997 998
	}

999
	return 0;
1000 1001
}

1002
static int
1003
ieee80211_drop_unencrypted(struct ieee80211_txrx_data *rx)
1004
{
1005
	/*
1006 1007
	 * Pass through unencrypted frames if the hardware has
	 * decrypted them already.
1008
	 */
1009
	if (rx->u.rx.status->flag & RX_FLAG_DECRYPTED)
1010
		return 0;
1011 1012 1013 1014 1015

	/* Drop unencrypted frames if key is set. */
	if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) &&
		     (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
		     (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
1016
		     (rx->key || rx->sdata->drop_unencrypted))) {
1017 1018 1019
		if (net_ratelimit())
			printk(KERN_DEBUG "%s: RX non-WEP frame, but expected "
			       "encryption\n", rx->dev->name);
1020
		return -EACCES;
1021
	}
1022
	return 0;
1023 1024
}

1025 1026
static int
ieee80211_data_to_8023(struct ieee80211_txrx_data *rx)
1027 1028 1029 1030 1031 1032 1033
{
	struct net_device *dev = rx->dev;
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
	u16 fc, hdrlen, ethertype;
	u8 *payload;
	u8 dst[ETH_ALEN];
	u8 src[ETH_ALEN];
1034
	struct sk_buff *skb = rx->skb;
1035
	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1036 1037 1038 1039
	DECLARE_MAC_BUF(mac);
	DECLARE_MAC_BUF(mac2);
	DECLARE_MAC_BUF(mac3);
	DECLARE_MAC_BUF(mac4);
1040 1041 1042 1043

	fc = rx->fc;

	if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1044
		return -1;
1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063

	hdrlen = ieee80211_get_hdrlen(fc);

	/* convert IEEE 802.11 header + possible LLC headers into Ethernet
	 * header
	 * IEEE 802.11 address fields:
	 * ToDS FromDS Addr1 Addr2 Addr3 Addr4
	 *   0     0   DA    SA    BSSID n/a
	 *   0     1   DA    BSSID SA    n/a
	 *   1     0   BSSID SA    DA    n/a
	 *   1     1   RA    TA    DA    SA
	 */

	switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
	case IEEE80211_FCTL_TODS:
		/* BSSID SA DA */
		memcpy(dst, hdr->addr3, ETH_ALEN);
		memcpy(src, hdr->addr2, ETH_ALEN);

1064 1065
		if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_AP &&
			     sdata->vif.type != IEEE80211_IF_TYPE_VLAN)) {
1066 1067
			if (net_ratelimit())
				printk(KERN_DEBUG "%s: dropped ToDS frame "
1068
				       "(BSSID=%s SA=%s DA=%s)\n",
1069
				       dev->name,
1070 1071 1072
				       print_mac(mac, hdr->addr1),
				       print_mac(mac2, hdr->addr2),
				       print_mac(mac3, hdr->addr3));
1073
			return -1;
1074 1075 1076 1077 1078 1079 1080
		}
		break;
	case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
		/* RA TA DA SA */
		memcpy(dst, hdr->addr3, ETH_ALEN);
		memcpy(src, hdr->addr4, ETH_ALEN);

1081
		if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_WDS)) {
1082 1083
			if (net_ratelimit())
				printk(KERN_DEBUG "%s: dropped FromDS&ToDS "
1084
				       "frame (RA=%s TA=%s DA=%s SA=%s)\n",
1085
				       rx->dev->name,
1086 1087 1088 1089
				       print_mac(mac, hdr->addr1),
				       print_mac(mac2, hdr->addr2),
				       print_mac(mac3, hdr->addr3),
				       print_mac(mac4, hdr->addr4));
1090
			return -1;
1091 1092 1093 1094 1095 1096 1097
		}
		break;
	case IEEE80211_FCTL_FROMDS:
		/* DA BSSID SA */
		memcpy(dst, hdr->addr1, ETH_ALEN);
		memcpy(src, hdr->addr3, ETH_ALEN);

1098
		if (sdata->vif.type != IEEE80211_IF_TYPE_STA ||
1099 1100
		    (is_multicast_ether_addr(dst) &&
		     !compare_ether_addr(src, dev->dev_addr)))
1101
			return -1;
1102 1103 1104 1105 1106 1107
		break;
	case 0:
		/* DA SA BSSID */
		memcpy(dst, hdr->addr1, ETH_ALEN);
		memcpy(src, hdr->addr2, ETH_ALEN);

1108
		if (sdata->vif.type != IEEE80211_IF_TYPE_IBSS) {
1109
			if (net_ratelimit()) {
1110 1111 1112 1113 1114 1115
				printk(KERN_DEBUG "%s: dropped IBSS frame "
				       "(DA=%s SA=%s BSSID=%s)\n",
				       dev->name,
				       print_mac(mac, hdr->addr1),
				       print_mac(mac2, hdr->addr2),
				       print_mac(mac3, hdr->addr3));
1116
			}
1117
			return -1;
1118 1119 1120 1121 1122 1123 1124 1125 1126
		}
		break;
	}

	if (unlikely(skb->len - hdrlen < 8)) {
		if (net_ratelimit()) {
			printk(KERN_DEBUG "%s: RX too short data frame "
			       "payload\n", dev->name);
		}
1127
		return -1;
1128 1129
	}

1130
	payload = skb->data + hdrlen;
1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143
	ethertype = (payload[6] << 8) | payload[7];

	if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
		    ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
		   compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
		/* remove RFC1042 or Bridge-Tunnel encapsulation and
		 * replace EtherType */
		skb_pull(skb, hdrlen + 6);
		memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
		memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
	} else {
		struct ethhdr *ehdr;
		__be16 len;
1144

1145 1146 1147 1148 1149 1150 1151
		skb_pull(skb, hdrlen);
		len = htons(skb->len);
		ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
		memcpy(ehdr->h_dest, dst, ETH_ALEN);
		memcpy(ehdr->h_source, src, ETH_ALEN);
		ehdr->h_proto = len;
	}
1152 1153
	return 0;
}
1154

1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182
/*
 * requires that rx->skb is a frame with ethernet header
 */
static bool ieee80211_frame_allowed(struct ieee80211_txrx_data *rx)
{
	static const u8 pae_group_addr[ETH_ALEN]
		= { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;

	/*
	 * Allow EAPOL frames to us/the PAE group address regardless
	 * of whether the frame was encrypted or not.
	 */
	if (ehdr->h_proto == htons(ETH_P_PAE) &&
	    (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
	     compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
		return true;

	if (ieee80211_802_1x_port_control(rx) ||
	    ieee80211_drop_unencrypted(rx))
		return false;

	return true;
}

/*
 * requires that rx->skb is a frame with ethernet header
 */
1183 1184 1185 1186 1187 1188 1189
static void
ieee80211_deliver_skb(struct ieee80211_txrx_data *rx)
{
	struct net_device *dev = rx->dev;
	struct ieee80211_local *local = rx->local;
	struct sk_buff *skb, *xmit_skb;
	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1190 1191
	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
	struct sta_info *dsta;
1192

1193 1194
	skb = rx->skb;
	xmit_skb = NULL;
1195

1196 1197
	if (local->bridge_packets && (sdata->vif.type == IEEE80211_IF_TYPE_AP ||
				      sdata->vif.type == IEEE80211_IF_TYPE_VLAN) &&
1198
	    (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
1199 1200 1201 1202 1203
		if (is_multicast_ether_addr(ehdr->h_dest)) {
			/*
			 * send multicast frames both to higher layers in
			 * local net stack and back to the wireless medium
			 */
1204 1205
			xmit_skb = skb_copy(skb, GFP_ATOMIC);
			if (!xmit_skb && net_ratelimit())
1206 1207 1208 1209
				printk(KERN_DEBUG "%s: failed to clone "
				       "multicast frame\n", dev->name);
		} else {
			dsta = sta_info_get(local, skb->data);
1210 1211 1212 1213 1214 1215
			if (dsta && dsta->dev == dev) {
				/*
				 * The destination station is associated to
				 * this AP (in this VLAN), so send the frame
				 * directly to it and do not pass it to local
				 * net stack.
1216
				 */
1217
				xmit_skb = skb;
1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231
				skb = NULL;
			}
			if (dsta)
				sta_info_put(dsta);
		}
	}

	if (skb) {
		/* deliver to local stack */
		skb->protocol = eth_type_trans(skb, dev);
		memset(skb->cb, 0, sizeof(skb->cb));
		netif_rx(skb);
	}

1232
	if (xmit_skb) {
1233
		/* send to wireless media */
1234
		xmit_skb->protocol = htons(ETH_P_802_3);
1235 1236
		skb_reset_network_header(xmit_skb);
		skb_reset_mac_header(xmit_skb);
1237
		dev_queue_xmit(xmit_skb);
1238
	}
1239 1240
}

1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261
static ieee80211_txrx_result
ieee80211_rx_h_amsdu(struct ieee80211_txrx_data *rx)
{
	struct net_device *dev = rx->dev;
	struct ieee80211_local *local = rx->local;
	u16 fc, ethertype;
	u8 *payload;
	struct sk_buff *skb = rx->skb, *frame = NULL;
	const struct ethhdr *eth;
	int remaining, err;
	u8 dst[ETH_ALEN];
	u8 src[ETH_ALEN];
	DECLARE_MAC_BUF(mac);

	fc = rx->fc;
	if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
		return TXRX_CONTINUE;

	if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
		return TXRX_DROP;

1262
	if (!(rx->flags & IEEE80211_TXRXD_RX_AMSDU))
1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320
		return TXRX_CONTINUE;

	err = ieee80211_data_to_8023(rx);
	if (unlikely(err))
		return TXRX_DROP;

	skb->dev = dev;

	dev->stats.rx_packets++;
	dev->stats.rx_bytes += skb->len;

	/* skip the wrapping header */
	eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
	if (!eth)
		return TXRX_DROP;

	while (skb != frame) {
		u8 padding;
		__be16 len = eth->h_proto;
		unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);

		remaining = skb->len;
		memcpy(dst, eth->h_dest, ETH_ALEN);
		memcpy(src, eth->h_source, ETH_ALEN);

		padding = ((4 - subframe_len) & 0x3);
		/* the last MSDU has no padding */
		if (subframe_len > remaining) {
			printk(KERN_DEBUG "%s: wrong buffer size", dev->name);
			return TXRX_DROP;
		}

		skb_pull(skb, sizeof(struct ethhdr));
		/* if last subframe reuse skb */
		if (remaining <= subframe_len + padding)
			frame = skb;
		else {
			frame = dev_alloc_skb(local->hw.extra_tx_headroom +
					      subframe_len);

			if (frame == NULL)
				return TXRX_DROP;

			skb_reserve(frame, local->hw.extra_tx_headroom +
				    sizeof(struct ethhdr));
			memcpy(skb_put(frame, ntohs(len)), skb->data,
				ntohs(len));

			eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
							padding);
			if (!eth) {
				printk(KERN_DEBUG "%s: wrong buffer size ",
				       dev->name);
				dev_kfree_skb(frame);
				return TXRX_DROP;
			}
		}

1321
		skb_reset_network_header(frame);
1322 1323 1324 1325 1326 1327 1328 1329
		frame->dev = dev;
		frame->priority = skb->priority;
		rx->skb = frame;

		payload = frame->data;
		ethertype = (payload[6] << 8) | payload[7];

		if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1330 1331 1332
			    ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
			   compare_ether_addr(payload,
					      bridge_tunnel_header) == 0)) {
1333 1334 1335 1336 1337 1338
			/* remove RFC1042 or Bridge-Tunnel
			 * encapsulation and replace EtherType */
			skb_pull(frame, 6);
			memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
			memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
		} else {
1339 1340
			memcpy(skb_push(frame, sizeof(__be16)),
			       &len, sizeof(__be16));
1341 1342 1343 1344
			memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
			memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
		}

1345 1346 1347 1348 1349 1350
		if (!ieee80211_frame_allowed(rx)) {
			if (skb == frame) /* last frame */
				return TXRX_DROP;
			dev_kfree_skb(frame);
			continue;
		}
1351 1352 1353 1354 1355 1356 1357

		ieee80211_deliver_skb(rx);
	}

	return TXRX_QUEUED;
}

1358 1359 1360 1361 1362
static ieee80211_txrx_result
ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
{
	struct net_device *dev = rx->dev;
	u16 fc;
1363
	int err;
1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375

	fc = rx->fc;
	if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
		return TXRX_CONTINUE;

	if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
		return TXRX_DROP;

	err = ieee80211_data_to_8023(rx);
	if (unlikely(err))
		return TXRX_DROP;

1376 1377 1378
	if (!ieee80211_frame_allowed(rx))
		return TXRX_DROP;

1379 1380 1381 1382 1383 1384
	rx->skb->dev = dev;

	dev->stats.rx_packets++;
	dev->stats.rx_bytes += rx->skb->len;

	ieee80211_deliver_skb(rx);
1385 1386 1387 1388

	return TXRX_QUEUED;
}

1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431
static ieee80211_txrx_result
ieee80211_rx_h_ctrl(struct ieee80211_txrx_data *rx)
{
	struct ieee80211_local *local = rx->local;
	struct ieee80211_hw *hw = &local->hw;
	struct sk_buff *skb = rx->skb;
	struct ieee80211_bar *bar = (struct ieee80211_bar *) skb->data;
	struct tid_ampdu_rx *tid_agg_rx;
	u16 start_seq_num;
	u16 tid;

	if (likely((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL))
		return TXRX_CONTINUE;

	if ((rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BACK_REQ) {
		if (!rx->sta)
			return TXRX_CONTINUE;
		tid = le16_to_cpu(bar->control) >> 12;
		tid_agg_rx = &(rx->sta->ampdu_mlme.tid_rx[tid]);
		if (tid_agg_rx->state != HT_AGG_STATE_OPERATIONAL)
			return TXRX_CONTINUE;

		start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;

		/* reset session timer */
		if (tid_agg_rx->timeout) {
			unsigned long expires =
				jiffies + (tid_agg_rx->timeout / 1000) * HZ;
			mod_timer(&tid_agg_rx->session_timer, expires);
		}

		/* manage reordering buffer according to requested */
		/* sequence number */
		rcu_read_lock();
		ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
						 start_seq_num, 1);
		rcu_read_unlock();
		return TXRX_DROP;
	}

	return TXRX_CONTINUE;
}

1432 1433 1434 1435 1436
static ieee80211_txrx_result
ieee80211_rx_h_mgmt(struct ieee80211_txrx_data *rx)
{
	struct ieee80211_sub_if_data *sdata;

1437
	if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
1438 1439 1440
		return TXRX_DROP;

	sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1441 1442
	if ((sdata->vif.type == IEEE80211_IF_TYPE_STA ||
	     sdata->vif.type == IEEE80211_IF_TYPE_IBSS) &&
1443
	    !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
1444
		ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->u.rx.status);
1445 1446 1447
	else
		return TXRX_DROP;

1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461
	return TXRX_QUEUED;
}

static inline ieee80211_txrx_result __ieee80211_invoke_rx_handlers(
				struct ieee80211_local *local,
				ieee80211_rx_handler *handlers,
				struct ieee80211_txrx_data *rx,
				struct sta_info *sta)
{
	ieee80211_rx_handler *handler;
	ieee80211_txrx_result res = TXRX_DROP;

	for (handler = handlers; *handler != NULL; handler++) {
		res = (*handler)(rx);
J
Johannes Berg 已提交
1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472

		switch (res) {
		case TXRX_CONTINUE:
			continue;
		case TXRX_DROP:
			I802_DEBUG_INC(local->rx_handlers_drop);
			if (sta)
				sta->rx_dropped++;
			break;
		case TXRX_QUEUED:
			I802_DEBUG_INC(local->rx_handlers_queued);
1473 1474
			break;
		}
J
Johannes Berg 已提交
1475
		break;
1476 1477
	}

J
Johannes Berg 已提交
1478
	if (res == TXRX_DROP)
1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498
		dev_kfree_skb(rx->skb);
	return res;
}

static inline void ieee80211_invoke_rx_handlers(struct ieee80211_local *local,
						ieee80211_rx_handler *handlers,
						struct ieee80211_txrx_data *rx,
						struct sta_info *sta)
{
	if (__ieee80211_invoke_rx_handlers(local, handlers, rx, sta) ==
	    TXRX_CONTINUE)
		dev_kfree_skb(rx->skb);
}

static void ieee80211_rx_michael_mic_report(struct net_device *dev,
					    struct ieee80211_hdr *hdr,
					    struct sta_info *sta,
					    struct ieee80211_txrx_data *rx)
{
	int keyidx, hdrlen;
1499 1500
	DECLARE_MAC_BUF(mac);
	DECLARE_MAC_BUF(mac2);
1501 1502 1503 1504 1505 1506 1507

	hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb);
	if (rx->skb->len >= hdrlen + 4)
		keyidx = rx->skb->data[hdrlen + 3] >> 6;
	else
		keyidx = -1;

1508 1509
	if (net_ratelimit())
		printk(KERN_DEBUG "%s: TKIP hwaccel reported Michael MIC "
1510 1511 1512
		       "failure from %s to %s keyidx=%d\n",
		       dev->name, print_mac(mac, hdr->addr2),
		       print_mac(mac2, hdr->addr1), keyidx);
1513 1514

	if (!sta) {
1515 1516 1517 1518
		/*
		 * Some hardware seem to generate incorrect Michael MIC
		 * reports; ignore them to avoid triggering countermeasures.
		 */
1519 1520
		if (net_ratelimit())
			printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1521 1522
			       "error for unknown address %s\n",
			       dev->name, print_mac(mac, hdr->addr2));
1523 1524 1525 1526
		goto ignore;
	}

	if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) {
1527 1528
		if (net_ratelimit())
			printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1529
			       "error for a frame with no PROTECTED flag (src "
1530
			       "%s)\n", dev->name, print_mac(mac, hdr->addr2));
1531 1532 1533
		goto ignore;
	}

1534
	if (rx->sdata->vif.type == IEEE80211_IF_TYPE_AP && keyidx) {
1535 1536 1537 1538 1539 1540
		/*
		 * APs with pairwise keys should never receive Michael MIC
		 * errors for non-zero keyidx because these are reserved for
		 * group keys and only the AP is sending real multicast
		 * frames in the BSS.
		 */
J
Johannes Berg 已提交
1541 1542 1543
		if (net_ratelimit())
			printk(KERN_DEBUG "%s: ignored Michael MIC error for "
			       "a frame with non-zero keyidx (%d)"
1544 1545
			       " (src %s)\n", dev->name, keyidx,
			       print_mac(mac, hdr->addr2));
J
Johannes Berg 已提交
1546
		goto ignore;
1547 1548 1549 1550 1551
	}

	if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
	    ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
	     (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)) {
1552 1553 1554
		if (net_ratelimit())
			printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
			       "error for a frame that cannot be encrypted "
1555 1556
			       "(fc=0x%04x) (src %s)\n",
			       dev->name, rx->fc, print_mac(mac, hdr->addr2));
1557 1558 1559
		goto ignore;
	}

J
Johannes Berg 已提交
1560
	mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr);
1561 1562 1563 1564 1565 1566 1567 1568 1569 1570
 ignore:
	dev_kfree_skb(rx->skb);
	rx->skb = NULL;
}

ieee80211_rx_handler ieee80211_rx_handlers[] =
{
	ieee80211_rx_h_if_stats,
	ieee80211_rx_h_passive_scan,
	ieee80211_rx_h_check,
1571
	ieee80211_rx_h_decrypt,
1572
	ieee80211_rx_h_sta_process,
1573 1574 1575 1576 1577 1578 1579 1580
	ieee80211_rx_h_defragment,
	ieee80211_rx_h_ps_poll,
	ieee80211_rx_h_michael_mic_verify,
	/* this must be after decryption - so header is counted in MPDU mic
	 * must be before pae and data, so QOS_DATA format frames
	 * are not passed to user space by these functions
	 */
	ieee80211_rx_h_remove_qos_control,
1581
	ieee80211_rx_h_amsdu,
1582
	ieee80211_rx_h_data,
1583
	ieee80211_rx_h_ctrl,
1584 1585 1586 1587 1588 1589
	ieee80211_rx_h_mgmt,
	NULL
};

/* main receive path */

1590 1591 1592 1593 1594 1595
static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
				u8 *bssid, struct ieee80211_txrx_data *rx,
				struct ieee80211_hdr *hdr)
{
	int multicast = is_multicast_ether_addr(hdr->addr1);

1596
	switch (sdata->vif.type) {
1597 1598 1599 1600
	case IEEE80211_IF_TYPE_STA:
		if (!bssid)
			return 0;
		if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1601
			if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1602
				return 0;
1603
			rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1604 1605 1606
		} else if (!multicast &&
			   compare_ether_addr(sdata->dev->dev_addr,
					      hdr->addr1) != 0) {
1607
			if (!(sdata->dev->flags & IFF_PROMISC))
1608
				return 0;
1609
			rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1610 1611 1612 1613 1614 1615
		}
		break;
	case IEEE80211_IF_TYPE_IBSS:
		if (!bssid)
			return 0;
		if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1616
			if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1617
				return 0;
1618
			rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1619 1620 1621
		} else if (!multicast &&
			   compare_ether_addr(sdata->dev->dev_addr,
					      hdr->addr1) != 0) {
1622
			if (!(sdata->dev->flags & IFF_PROMISC))
1623
				return 0;
1624
			rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1625 1626 1627 1628
		} else if (!rx->sta)
			rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
							 bssid, hdr->addr2);
		break;
J
Johannes Berg 已提交
1629
	case IEEE80211_IF_TYPE_VLAN:
1630 1631 1632 1633 1634 1635 1636
	case IEEE80211_IF_TYPE_AP:
		if (!bssid) {
			if (compare_ether_addr(sdata->dev->dev_addr,
					       hdr->addr1))
				return 0;
		} else if (!ieee80211_bssid_match(bssid,
					sdata->dev->dev_addr)) {
1637
			if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1638
				return 0;
1639
			rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1640
		}
1641 1642
		if (sdata->dev == sdata->local->mdev &&
		    !(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653
			/* do not receive anything via
			 * master device when not scanning */
			return 0;
		break;
	case IEEE80211_IF_TYPE_WDS:
		if (bssid ||
		    (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
			return 0;
		if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
			return 0;
		break;
J
Johannes Berg 已提交
1654 1655 1656
	case IEEE80211_IF_TYPE_MNTR:
		/* take everything */
		break;
1657
	case IEEE80211_IF_TYPE_INVALID:
J
Johannes Berg 已提交
1658 1659 1660
		/* should never get here */
		WARN_ON(1);
		break;
1661 1662 1663 1664 1665
	}

	return 1;
}

1666
/*
1667 1668
 * This is the actual Rx frames handler. as it blongs to Rx path it must
 * be called with rcu_read_lock protection.
1669
 */
1670 1671 1672
static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
					 struct sk_buff *skb,
					 struct ieee80211_rx_status *status,
1673 1674
					 u32 load,
					 struct ieee80211_rate *rate)
1675 1676 1677 1678 1679 1680 1681
{
	struct ieee80211_local *local = hw_to_local(hw);
	struct ieee80211_sub_if_data *sdata;
	struct sta_info *sta;
	struct ieee80211_hdr *hdr;
	struct ieee80211_txrx_data rx;
	u16 type;
1682
	int prepares;
J
Johannes Berg 已提交
1683 1684 1685
	struct ieee80211_sub_if_data *prev = NULL;
	struct sk_buff *skb_new;
	u8 *bssid;
1686 1687 1688 1689 1690 1691 1692

	hdr = (struct ieee80211_hdr *) skb->data;
	memset(&rx, 0, sizeof(rx));
	rx.skb = skb;
	rx.local = local;

	rx.u.rx.status = status;
1693
	rx.u.rx.load = load;
1694
	rx.u.rx.rate = rate;
1695
	rx.fc = le16_to_cpu(hdr->frame_control);
1696
	type = rx.fc & IEEE80211_FCTL_FTYPE;
1697

1698
	if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT)
1699 1700
		local->dot11ReceivedFragmentCount++;

1701 1702 1703 1704 1705
	sta = rx.sta = sta_info_get(local, hdr->addr2);
	if (sta) {
		rx.dev = rx.sta->dev;
		rx.sdata = IEEE80211_DEV_TO_SUB_IF(rx.dev);
	}
1706 1707 1708 1709 1710 1711

	if ((status->flag & RX_FLAG_MMIC_ERROR)) {
		ieee80211_rx_michael_mic_report(local->mdev, hdr, sta, &rx);
		goto end;
	}

Z
Zhu Yi 已提交
1712
	if (unlikely(local->sta_sw_scanning || local->sta_hw_scanning))
1713
		rx.flags |= IEEE80211_TXRXD_RXIN_SCAN;
1714

1715 1716 1717
	ieee80211_parse_qos(&rx);
	ieee80211_verify_ip_alignment(&rx);

1718 1719
	skb = rx.skb;

J
Johannes Berg 已提交
1720
	if (sta && !(sta->flags & (WLAN_STA_WDS | WLAN_STA_ASSOC_AP)) &&
1721 1722
	    !atomic_read(&local->iff_promiscs) &&
	    !is_multicast_ether_addr(hdr->addr1)) {
1723
		rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1724
		ieee80211_invoke_rx_handlers(local, local->rx_handlers, &rx,
1725
					     rx.sta);
J
Johannes Berg 已提交
1726 1727 1728 1729
		sta_info_put(sta);
		return;
	}

1730
	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1731 1732 1733
		if (!netif_running(sdata->dev))
			continue;

1734
		if (sdata->vif.type == IEEE80211_IF_TYPE_MNTR)
1735 1736
			continue;

1737
		bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
1738
		rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1739
		prepares = prepare_for_handlers(sdata, bssid, &rx, hdr);
1740 1741 1742
		/* prepare_for_handlers can change sta */
		sta = rx.sta;

1743
		if (!prepares)
1744
			continue;
J
Johannes Berg 已提交
1745

J
Johannes Berg 已提交
1746 1747 1748 1749 1750 1751 1752 1753 1754
		/*
		 * frame is destined for this interface, but if it's not
		 * also for the previous one we handle that after the
		 * loop to avoid copying the SKB once too much
		 */

		if (!prev) {
			prev = sdata;
			continue;
J
Johannes Berg 已提交
1755
		}
J
Johannes Berg 已提交
1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766

		/*
		 * frame was destined for the previous interface
		 * so invoke RX handlers for it
		 */

		skb_new = skb_copy(skb, GFP_ATOMIC);
		if (!skb_new) {
			if (net_ratelimit())
				printk(KERN_DEBUG "%s: failed to copy "
				       "multicast frame for %s",
1767 1768
				       wiphy_name(local->hw.wiphy),
				       prev->dev->name);
J
Johannes Berg 已提交
1769 1770
			continue;
		}
1771
		rx.fc = le16_to_cpu(hdr->frame_control);
J
Johannes Berg 已提交
1772 1773 1774 1775 1776
		rx.skb = skb_new;
		rx.dev = prev->dev;
		rx.sdata = prev;
		ieee80211_invoke_rx_handlers(local, local->rx_handlers,
					     &rx, sta);
J
Johannes Berg 已提交
1777
		prev = sdata;
1778
	}
J
Johannes Berg 已提交
1779
	if (prev) {
1780
		rx.fc = le16_to_cpu(hdr->frame_control);
J
Johannes Berg 已提交
1781 1782 1783 1784 1785 1786 1787
		rx.skb = skb;
		rx.dev = prev->dev;
		rx.sdata = prev;
		ieee80211_invoke_rx_handlers(local, local->rx_handlers,
					     &rx, sta);
	} else
		dev_kfree_skb(skb);
1788

J
Johannes Berg 已提交
1789
 end:
1790 1791 1792
	if (sta)
		sta_info_put(sta);
}
1793

1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812
#define SEQ_MODULO 0x1000
#define SEQ_MASK   0xfff

static inline int seq_less(u16 sq1, u16 sq2)
{
	return (((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1));
}

static inline u16 seq_inc(u16 sq)
{
	return ((sq + 1) & SEQ_MASK);
}

static inline u16 seq_sub(u16 sq1, u16 sq2)
{
	return ((sq1 - sq2) & SEQ_MASK);
}


1813 1814 1815 1816
/*
 * As it function blongs to Rx path it must be called with
 * the proper rcu_read_lock protection for its flow.
 */
1817 1818 1819 1820 1821 1822 1823 1824 1825 1826
u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
				struct tid_ampdu_rx *tid_agg_rx,
				struct sk_buff *skb, u16 mpdu_seq_num,
				int bar_req)
{
	struct ieee80211_local *local = hw_to_local(hw);
	struct ieee80211_rx_status status;
	u16 head_seq_num, buf_size;
	int index;
	u32 pkt_load;
1827 1828
	struct ieee80211_supported_band *sband;
	struct ieee80211_rate *rate;
1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858

	buf_size = tid_agg_rx->buf_size;
	head_seq_num = tid_agg_rx->head_seq_num;

	/* frame with out of date sequence number */
	if (seq_less(mpdu_seq_num, head_seq_num)) {
		dev_kfree_skb(skb);
		return 1;
	}

	/* if frame sequence number exceeds our buffering window size or
	 * block Ack Request arrived - release stored frames */
	if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
		/* new head to the ordering buffer */
		if (bar_req)
			head_seq_num = mpdu_seq_num;
		else
			head_seq_num =
				seq_inc(seq_sub(mpdu_seq_num, buf_size));
		/* release stored frames up to new head to stack */
		while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
			index = seq_sub(tid_agg_rx->head_seq_num,
				tid_agg_rx->ssn)
				% tid_agg_rx->buf_size;

			if (tid_agg_rx->reorder_buf[index]) {
				/* release the reordered frames to stack */
				memcpy(&status,
					tid_agg_rx->reorder_buf[index]->cb,
					sizeof(status));
1859 1860
				sband = local->hw.wiphy->bands[status.band];
				rate = &sband->bitrates[status.rate_idx];
1861 1862
				pkt_load = ieee80211_rx_load_stats(local,
						tid_agg_rx->reorder_buf[index],
1863
						&status, rate);
1864 1865
				__ieee80211_rx_handle_packet(hw,
					tid_agg_rx->reorder_buf[index],
1866
					&status, pkt_load, rate);
1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905
				tid_agg_rx->stored_mpdu_num--;
				tid_agg_rx->reorder_buf[index] = NULL;
			}
			tid_agg_rx->head_seq_num =
				seq_inc(tid_agg_rx->head_seq_num);
		}
		if (bar_req)
			return 1;
	}

	/* now the new frame is always in the range of the reordering */
	/* buffer window */
	index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
				% tid_agg_rx->buf_size;
	/* check if we already stored this frame */
	if (tid_agg_rx->reorder_buf[index]) {
		dev_kfree_skb(skb);
		return 1;
	}

	/* if arrived mpdu is in the right order and nothing else stored */
	/* release it immediately */
	if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
			tid_agg_rx->stored_mpdu_num == 0) {
		tid_agg_rx->head_seq_num =
			seq_inc(tid_agg_rx->head_seq_num);
		return 0;
	}

	/* put the frame in the reordering buffer */
	tid_agg_rx->reorder_buf[index] = skb;
	tid_agg_rx->stored_mpdu_num++;
	/* release the buffer until next missing frame */
	index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
						% tid_agg_rx->buf_size;
	while (tid_agg_rx->reorder_buf[index]) {
		/* release the reordered frame back to stack */
		memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
			sizeof(status));
1906 1907
		sband = local->hw.wiphy->bands[status.band];
		rate = &sband->bitrates[status.rate_idx];
1908 1909
		pkt_load = ieee80211_rx_load_stats(local,
					tid_agg_rx->reorder_buf[index],
1910
					&status, rate);
1911
		__ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
1912
					     &status, pkt_load, rate);
1913 1914 1915 1916 1917 1918 1919 1920 1921
		tid_agg_rx->stored_mpdu_num--;
		tid_agg_rx->reorder_buf[index] = NULL;
		tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
		index =	seq_sub(tid_agg_rx->head_seq_num,
			tid_agg_rx->ssn) % tid_agg_rx->buf_size;
	}
	return 1;
}

1922 1923
static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
				     struct sk_buff *skb)
1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952
{
	struct ieee80211_hw *hw = &local->hw;
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
	struct sta_info *sta;
	struct tid_ampdu_rx *tid_agg_rx;
	u16 fc, sc;
	u16 mpdu_seq_num;
	u8 ret = 0, *qc;
	int tid;

	sta = sta_info_get(local, hdr->addr2);
	if (!sta)
		return ret;

	fc = le16_to_cpu(hdr->frame_control);

	/* filter the QoS data rx stream according to
	 * STA/TID and check if this STA/TID is on aggregation */
	if (!WLAN_FC_IS_QOS_DATA(fc))
		goto end_reorder;

	qc = skb->data + ieee80211_get_hdrlen(fc) - QOS_CONTROL_LEN;
	tid = qc[0] & QOS_CONTROL_TID_MASK;
	tid_agg_rx = &(sta->ampdu_mlme.tid_rx[tid]);

	if (tid_agg_rx->state != HT_AGG_STATE_OPERATIONAL)
		goto end_reorder;

	/* null data frames are excluded */
1953
	if (unlikely(fc & IEEE80211_STYPE_NULLFUNC))
1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983
		goto end_reorder;

	/* new un-ordered ampdu frame - process it */

	/* reset session timer */
	if (tid_agg_rx->timeout) {
		unsigned long expires =
			jiffies + (tid_agg_rx->timeout / 1000) * HZ;
		mod_timer(&tid_agg_rx->session_timer, expires);
	}

	/* if this mpdu is fragmented - terminate rx aggregation session */
	sc = le16_to_cpu(hdr->seq_ctrl);
	if (sc & IEEE80211_SCTL_FRAG) {
		ieee80211_sta_stop_rx_ba_session(sta->dev, sta->addr,
			tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
		ret = 1;
		goto end_reorder;
	}

	/* according to mpdu sequence number deal with reordering buffer */
	mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
	ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
						mpdu_seq_num, 0);
end_reorder:
	if (sta)
		sta_info_put(sta);
	return ret;
}

1984 1985 1986 1987 1988 1989 1990 1991 1992
/*
 * This is the receive path handler. It is called by a low level driver when an
 * 802.11 MPDU is received from the hardware.
 */
void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
		    struct ieee80211_rx_status *status)
{
	struct ieee80211_local *local = hw_to_local(hw);
	u32 pkt_load;
1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
	struct ieee80211_rate *rate = NULL;
	struct ieee80211_supported_band *sband;

	if (status->band < 0 ||
	    status->band > IEEE80211_NUM_BANDS) {
		WARN_ON(1);
		return;
	}

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

	if (!sband ||
	    status->rate_idx < 0 ||
	    status->rate_idx >= sband->n_bitrates) {
		WARN_ON(1);
		return;
	}

	rate = &sband->bitrates[status->rate_idx];
2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025

	/*
	 * key references and virtual interfaces are protected using RCU
	 * and this requires that we are in a read-side RCU section during
	 * receive processing
	 */
	rcu_read_lock();

	/*
	 * Frames with failed FCS/PLCP checksum are not returned,
	 * all other frames are returned without radiotap header
	 * if it was previously present.
	 * Also, frames with less than 16 bytes are dropped.
	 */
2026
	skb = ieee80211_rx_monitor(local, skb, status, rate);
2027 2028 2029 2030 2031
	if (!skb) {
		rcu_read_unlock();
		return;
	}

2032
	pkt_load = ieee80211_rx_load_stats(local, skb, status, rate);
2033
	local->channel_use_raw += pkt_load;
2034

2035
	if (!ieee80211_rx_reorder_ampdu(local, skb))
2036
		__ieee80211_rx_handle_packet(hw, skb, status, pkt_load, rate);
2037 2038 2039

	rcu_read_unlock();
}
2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058
EXPORT_SYMBOL(__ieee80211_rx);

/* This is a version of the rx handler that can be called from hard irq
 * context. Post the skb on the queue and schedule the tasklet */
void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
			  struct ieee80211_rx_status *status)
{
	struct ieee80211_local *local = hw_to_local(hw);

	BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));

	skb->dev = local->mdev;
	/* copy status into skb->cb for use by tasklet */
	memcpy(skb->cb, status, sizeof(*status));
	skb->pkt_type = IEEE80211_RX_MSG;
	skb_queue_tail(&local->skb_queue, skb);
	tasklet_schedule(&local->tasklet);
}
EXPORT_SYMBOL(ieee80211_rx_irqsafe);