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12446c67fe
linux/net/mac80211/rx.c
Ron Rindjunsky 98f0b0a3a4 mac80211: pass in PS_POLL frames 
This patch fixes should_drop_frame function to pass in ps poll control
frames required for power save functioanlity. Interface types that do not
have interest for PS POLL frames now drop it in handler.

Signed-off-by: Ron Rindjunsky <ron.rindjunsky@intel.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:59:16 -08:00

1787 lines
50 KiB
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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>
#include <linux/rcupdate.h>
#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"
/*
* 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;
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)) !=
cpu_to_le16(IEEE80211_STYPE_PSPOLL)))
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,
struct ieee80211_rx_status *status)
{
struct ieee80211_sub_if_data *sdata;
struct ieee80211_rate *rate;
int needed_headroom = 0;
struct ieee80211_radiotap_header *rthdr;
__le64 *rttsft = NULL;
struct ieee80211_rtap_fixed_data {
u8 flags;
u8 rate;
__le16 chan_freq;
__le16 chan_flags;
u8 antsignal;
u8 padding_for_rxflags;
__le16 rx_flags;
} __attribute__ ((packed)) *rtfixed;
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
/* room for radiotap header, always present fields and TSFT */
needed_headroom = sizeof(*rthdr) + sizeof(*rtfixed) + 8;
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 &&
pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
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)) {
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;
}
rthdr = (void *) skb_push(skb, sizeof(*rthdr));
memset(rthdr, 0, sizeof(*rthdr));
memset(rtfixed, 0, sizeof(*rtfixed));
rthdr->it_present =
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));
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);
}
/* FIXME: when radiotap gets a 'bad PLCP' flag use it here */
rtfixed->rx_flags = 0;
if (status->flag &
(RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
rtfixed->rx_flags |=
cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS);
rate = ieee80211_get_rate(local, status->phymode,
status->rate);
if (rate)
rtfixed->rate = rate->rate / 5;
rtfixed->chan_freq = cpu_to_le16(status->freq);
if (status->phymode == MODE_IEEE80211A)
rtfixed->chan_flags =
cpu_to_le16(IEEE80211_CHAN_OFDM |
IEEE80211_CHAN_5GHZ);
else
rtfixed->chan_flags =
cpu_to_le16(IEEE80211_CHAN_DYN |
IEEE80211_CHAN_2GHZ);
rtfixed->antsignal = status->ssi;
rthdr->it_len = cpu_to_le16(rtap_len);
}
skb_set_mac_header(skb, 0);
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;
if (sdata->type != IEEE80211_IF_TYPE_MNTR)
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;
}
/* pre-rx handlers
*
* these don't have dev/sdata fields in the rx data
* The sta value should also not be used because it may
* be NULL even though a STA (in IBSS mode) will be added.
*/
static ieee80211_txrx_result
ieee80211_rx_h_parse_qos(struct ieee80211_txrx_data *rx)
{
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;
if (qc[0] & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
rx->flags |= IEEE80211_TXRXD_RX_AMSDU;
else
rx->flags &= ~IEEE80211_TXRXD_RX_AMSDU;
} 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 */
}
}
I802_DEBUG_INC(rx->local->wme_rx_queue[tid]);
/* only a debug counter, sta might not be assigned properly yet */
if (rx->sta)
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;
return TXRX_CONTINUE;
}
static ieee80211_txrx_result
ieee80211_rx_h_load_stats(struct ieee80211_txrx_data *rx)
{
struct ieee80211_local *local = rx->local;
struct sk_buff *skb = rx->skb;
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
u32 load = 0, hdrtime;
struct ieee80211_rate *rate;
struct ieee80211_hw_mode *mode = local->hw.conf.mode;
int i;
/* Estimate total channel use caused by this frame */
if (unlikely(mode->num_rates < 0))
return TXRX_CONTINUE;
rate = &mode->rates[0];
for (i = 0; i < mode->num_rates; i++) {
if (mode->rates[i].val == rx->u.rx.status->rate) {
rate = &mode->rates[i];
break;
}
}
/* 1 bit at 1 Mbit/s takes 1 usec; in channel_use values,
* 1 usec = 1/8 * (1080 / 10) = 13.5 */
if (mode->mode == MODE_IEEE80211A ||
(mode->mode == MODE_IEEE80211G &&
rate->flags & IEEE80211_RATE_ERP))
hdrtime = CHAN_UTIL_HDR_SHORT;
else
hdrtime = CHAN_UTIL_HDR_LONG;
load = hdrtime;
if (!is_multicast_ether_addr(hdr->addr1))
load += hdrtime;
load += skb->len * rate->rate_inv;
/* Divide channel_use by 8 to avoid wrapping around the counter */
load >>= CHAN_UTIL_SHIFT;
local->channel_use_raw += load;
rx->u.rx.load = load;
return TXRX_CONTINUE;
}
ieee80211_rx_handler ieee80211_rx_pre_handlers[] =
{
ieee80211_rx_h_parse_qos,
ieee80211_rx_h_load_stats,
NULL
};
/* rx handlers */
static ieee80211_txrx_result
ieee80211_rx_h_if_stats(struct ieee80211_txrx_data *rx)
{
if (rx->sta)
rx->sta->channel_use_raw += rx->u.rx.load;
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;
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);
return TXRX_QUEUED;
}
if (unlikely(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) {
/* 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)) {
if (rx->flags & IEEE80211_TXRXD_RXRA_MATCH) {
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;
}
if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
rx->skb->pkt_type = PACKET_OTHERHOST;
else if (compare_ether_addr(rx->dev->dev_addr, hdr->addr1) == 0)
rx->skb->pkt_type = PACKET_HOST;
else if (is_multicast_ether_addr(hdr->addr1)) {
if (is_broadcast_ether_addr(hdr->addr1))
rx->skb->pkt_type = PACKET_BROADCAST;
else
rx->skb->pkt_type = PACKET_MULTICAST;
} else
rx->skb->pkt_type = PACKET_OTHERHOST;
/* 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)) &&
rx->sdata->type != IEEE80211_IF_TYPE_IBSS &&
(!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)
|| !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
/* Drop IBSS frames and frames for other hosts
* silently. */
return TXRX_DROP;
}
return TXRX_DROP;
}
return TXRX_CONTINUE;
}
static ieee80211_txrx_result
ieee80211_rx_h_decrypt(struct ieee80211_txrx_data *rx)
{
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
int keyidx;
int hdrlen;
ieee80211_txrx_result result = TXRX_DROP;
struct ieee80211_key *stakey = NULL;
/*
* 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.
*
* 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.
*
* There is also a slight problem in IBSS mode: GTKs are negotiated
* with each station, that is something we don't currently handle.
* The spec seems to expect that one negotiates the same key with
* every station but there's no such requirement; VLANs could be
* possible.
*/
if (!(rx->fc & IEEE80211_FCTL_PROTECTED))
return TXRX_CONTINUE;
/*
* No point in finding a key and decrypting if the frame is neither
* addressed to us nor a multicast frame.
*/
if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
return TXRX_CONTINUE;
if (rx->sta)
stakey = rcu_dereference(rx->sta->key);
if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
rx->key = stakey;
} else {
/*
* 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?
*/
if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED))
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;
rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
/*
* 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.
*/
if (rx->key && rx->key->conf.alg != ALG_WEP &&
!is_multicast_ether_addr(hdr->addr1))
rx->key = NULL;
}
if (rx->key) {
rx->key->tx_rx_count++;
/* TODO: add threshold stuff again */
} else {
#ifdef CONFIG_MAC80211_DEBUG
if (net_ratelimit())
printk(KERN_DEBUG "%s: RX protected frame,"
" but have no key\n", rx->dev->name);
#endif /* CONFIG_MAC80211_DEBUG */
return TXRX_DROP;
}
/* 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++;
switch (rx->key->conf.alg) {
case ALG_WEP:
result = ieee80211_crypto_wep_decrypt(rx);
break;
case ALG_TKIP:
result = ieee80211_crypto_tkip_decrypt(rx);
break;
case ALG_CCMP:
result = ieee80211_crypto_ccmp_decrypt(rx);
break;
}
/* either the frame has been decrypted or will be dropped */
rx->u.rx.status->flag |= RX_FLAG_DECRYPTED;
return result;
}
static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta)
{
struct ieee80211_sub_if_data *sdata;
DECLARE_MAC_BUF(mac);
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
printk(KERN_DEBUG "%s: STA %s aid %d enters power save mode\n",
dev->name, print_mac(mac, sta->addr), sta->aid);
#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;
DECLARE_MAC_BUF(mac);
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
printk(KERN_DEBUG "%s: STA %s aid %d exits power save mode\n",
dev->name, print_mac(mac, sta->addr), sta->aid);
#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++;
pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
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
printk(KERN_DEBUG "%s: STA %s aid %d send PS frame "
"since STA not sleeping anymore\n", dev->name,
print_mac(mac, sta->addr), sta->aid);
#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
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. */
if (rx->sdata->type == IEEE80211_IF_TYPE_IBSS) {
u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len);
if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
sta->last_rx = jiffies;
} else
if (!is_multicast_ether_addr(hdr->addr1) ||
rx->sdata->type == IEEE80211_IF_TYPE_STA) {
/* 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;
}
if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
return TXRX_CONTINUE;
sta->rx_fragments++;
sta->rx_bytes += rx->skb->len;
sta->last_rssi = rx->u.rx.status->ssi;
sta->last_signal = rx->u.rx.status->signal;
sta->last_noise = rx->u.rx.status->noise;
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;
DECLARE_MAC_BUF(mac);
DECLARE_MAC_BUF(mac2);
printk(KERN_DEBUG "%s: RX reassembly removed oldest "
"fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
"addr1=%s addr2=%s\n",
sdata->dev->name, idx,
jiffies - entry->first_frag_time, entry->seq,
entry->last_frag, print_mac(mac, hdr->addr1),
print_mac(mac2, hdr->addr2));
#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;
DECLARE_MAC_BUF(mac);
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));
if (rx->key && rx->key->conf.alg == ALG_CCMP &&
(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;
if (!rx->key || rx->key->conf.alg != ALG_CCMP)
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) {
if (net_ratelimit())
printk(KERN_DEBUG "%s: defrag: CCMP PN not "
"sequential A2=%s"
" PN=%02x%02x%02x%02x%02x%02x "
"(expected %02x%02x%02x%02x%02x%02x)\n",
rx->dev->name, print_mac(mac, hdr->addr2),
rpn[0], rpn[1], rpn[2], rpn[3], rpn[4],
rpn[5], pn[0], pn[1], pn[2], pn[3],
pn[4], pn[5]);
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 */
rx->flags |= IEEE80211_TXRXD_FRAGMENTED;
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)
{
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
struct sk_buff *skb;
int no_pending_pkts;
DECLARE_MAC_BUF(mac);
if (likely(!rx->sta ||
(rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL ||
(rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL ||
!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)))
return TXRX_CONTINUE;
if ((sdata->type != IEEE80211_IF_TYPE_AP) &&
(sdata->type != IEEE80211_IF_TYPE_VLAN))
return TXRX_DROP;
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
printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n",
print_mac(mac, rx->sta->addr), rx->sta->aid,
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) {
printk(KERN_DEBUG "%s: STA %s sent PS Poll even "
"though there is no buffered frames for it\n",
rx->dev->name, print_mac(mac, rx->sta->addr));
#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;
}
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;
}
static int
ieee80211_drop_802_1x_pae(struct ieee80211_txrx_data *rx, int hdrlen)
{
if (rx->sdata->eapol && ieee80211_is_eapol(rx->skb, hdrlen) &&
rx->sdata->type != IEEE80211_IF_TYPE_STA &&
(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
return 0;
if (unlikely(rx->sdata->ieee802_1x &&
(rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
(rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
(!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED)) &&
!ieee80211_is_eapol(rx->skb, hdrlen))) {
#ifdef CONFIG_MAC80211_DEBUG
printk(KERN_DEBUG "%s: dropped frame "
"(unauthorized port)\n", rx->dev->name);
#endif /* CONFIG_MAC80211_DEBUG */
return -EACCES;
}
return 0;
}
static int
ieee80211_drop_unencrypted(struct ieee80211_txrx_data *rx, int hdrlen)
{
/*
* Pass through unencrypted frames if the hardware has
* decrypted them already.
*/
if (rx->u.rx.status->flag & RX_FLAG_DECRYPTED)
return 0;
/* 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 &&
(rx->key || rx->sdata->drop_unencrypted) &&
(rx->sdata->eapol == 0 ||
!ieee80211_is_eapol(rx->skb, hdrlen)))) {
if (net_ratelimit())
printk(KERN_DEBUG "%s: RX non-WEP frame, but expected "
"encryption\n", rx->dev->name);
return -EACCES;
}
return 0;
}
static int
ieee80211_data_to_8023(struct ieee80211_txrx_data *rx)
{
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];
struct sk_buff *skb = rx->skb;
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
DECLARE_MAC_BUF(mac);
DECLARE_MAC_BUF(mac2);
DECLARE_MAC_BUF(mac3);
DECLARE_MAC_BUF(mac4);
fc = rx->fc;
if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
return -1;
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);
if (unlikely(sdata->type != IEEE80211_IF_TYPE_AP &&
sdata->type != IEEE80211_IF_TYPE_VLAN)) {
if (net_ratelimit())
printk(KERN_DEBUG "%s: dropped ToDS frame "
"(BSSID=%s SA=%s DA=%s)\n",
dev->name,
print_mac(mac, hdr->addr1),
print_mac(mac2, hdr->addr2),
print_mac(mac3, hdr->addr3));
return -1;
}
break;
case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
/* RA TA DA SA */
memcpy(dst, hdr->addr3, ETH_ALEN);
memcpy(src, hdr->addr4, ETH_ALEN);
if (unlikely(sdata->type != IEEE80211_IF_TYPE_WDS)) {
if (net_ratelimit())
printk(KERN_DEBUG "%s: dropped FromDS&ToDS "
"frame (RA=%s TA=%s DA=%s SA=%s)\n",
rx->dev->name,
print_mac(mac, hdr->addr1),
print_mac(mac2, hdr->addr2),
print_mac(mac3, hdr->addr3),
print_mac(mac4, hdr->addr4));
return -1;
}
break;
case IEEE80211_FCTL_FROMDS:
/* DA BSSID SA */
memcpy(dst, hdr->addr1, ETH_ALEN);
memcpy(src, hdr->addr3, ETH_ALEN);
if (sdata->type != IEEE80211_IF_TYPE_STA ||
(is_multicast_ether_addr(dst) &&
!compare_ether_addr(src, dev->dev_addr)))
return -1;
break;
case 0:
/* DA SA BSSID */
memcpy(dst, hdr->addr1, ETH_ALEN);
memcpy(src, hdr->addr2, ETH_ALEN);
if (sdata->type != IEEE80211_IF_TYPE_IBSS) {
if (net_ratelimit()) {
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));
}
return -1;
}
break;
}
if (unlikely(skb->len - hdrlen < 8)) {
if (net_ratelimit()) {
printk(KERN_DEBUG "%s: RX too short data frame "
"payload\n", dev->name);
}
return -1;
}
payload = skb->data + hdrlen;
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;
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;
}
return 0;
}
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);
skb = rx->skb;
xmit_skb = NULL;
if (local->bridge_packets && (sdata->type == IEEE80211_IF_TYPE_AP
|| sdata->type == IEEE80211_IF_TYPE_VLAN) &&
(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
if (is_multicast_ether_addr(skb->data)) {
/* send multicast frames both to higher layers in
* local net stack and back to the wireless media */
xmit_skb = skb_copy(skb, GFP_ATOMIC);
if (!xmit_skb && net_ratelimit())
printk(KERN_DEBUG "%s: failed to clone "
"multicast frame\n", dev->name);
} else {
struct sta_info *dsta;
dsta = sta_info_get(local, skb->data);
if (dsta && !dsta->dev) {
if (net_ratelimit())
printk(KERN_DEBUG "Station with null "
"dev structure!\n");
} else if (dsta && dsta->dev == dev) {
/* Destination station is associated to this
* AP, so send the frame directly to it and
* do not pass the frame to local net stack.
*/
xmit_skb = skb;
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);
}
if (xmit_skb) {
/* send to wireless media */
xmit_skb->protocol = htons(ETH_P_802_3);
skb_set_network_header(xmit_skb, 0);
skb_set_mac_header(xmit_skb, 0);
dev_queue_xmit(xmit_skb);
}
}
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;
if (!(rx->flags & IEEE80211_TXRXD_RX_AMSDU))
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;
}
}
skb_set_network_header(frame, 0);
frame->dev = dev;
frame->priority = skb->priority;
rx->skb = frame;
if ((ieee80211_drop_802_1x_pae(rx, 0)) ||
(ieee80211_drop_unencrypted(rx, 0))) {
if (skb == frame) /* last frame */
return TXRX_DROP;
dev_kfree_skb(frame);
continue;
}
payload = frame->data;
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(frame, 6);
memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
} else {
memcpy(skb_push(frame, sizeof(__be16)), &len,
sizeof(__be16));
memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
}
ieee80211_deliver_skb(rx);
}
return TXRX_QUEUED;
}
static ieee80211_txrx_result
ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
{
struct net_device *dev = rx->dev;
u16 fc;
int err, hdrlen;
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;
hdrlen = ieee80211_get_hdrlen(fc);
if ((ieee80211_drop_802_1x_pae(rx, hdrlen)) ||
(ieee80211_drop_unencrypted(rx, hdrlen)))
return TXRX_DROP;
err = ieee80211_data_to_8023(rx);
if (unlikely(err))
return TXRX_DROP;
rx->skb->dev = dev;
dev->stats.rx_packets++;
dev->stats.rx_bytes += rx->skb->len;
ieee80211_deliver_skb(rx);
return TXRX_QUEUED;
}
static ieee80211_txrx_result
ieee80211_rx_h_mgmt(struct ieee80211_txrx_data *rx)
{
struct ieee80211_sub_if_data *sdata;
if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
return TXRX_DROP;
sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
if ((sdata->type == IEEE80211_IF_TYPE_STA ||
sdata->type == IEEE80211_IF_TYPE_IBSS) &&
!(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->u.rx.status);
else
return TXRX_DROP;
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);
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);
break;
}
break;
}
if (res == TXRX_DROP)
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;
DECLARE_MAC_BUF(mac);
DECLARE_MAC_BUF(mac2);
hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb);
if (rx->skb->len >= hdrlen + 4)
keyidx = rx->skb->data[hdrlen + 3] >> 6;
else
keyidx = -1;
if (net_ratelimit())
printk(KERN_DEBUG "%s: TKIP hwaccel reported Michael MIC "
"failure from %s to %s keyidx=%d\n",
dev->name, print_mac(mac, hdr->addr2),
print_mac(mac2, hdr->addr1), keyidx);
if (!sta) {
/*
* Some hardware seem to generate incorrect Michael MIC
* reports; ignore them to avoid triggering countermeasures.
*/
if (net_ratelimit())
printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
"error for unknown address %s\n",
dev->name, print_mac(mac, hdr->addr2));
goto ignore;
}
if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) {
if (net_ratelimit())
printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
"error for a frame with no PROTECTED flag (src "
"%s)\n", dev->name, print_mac(mac, hdr->addr2));
goto ignore;
}
if (rx->sdata->type == IEEE80211_IF_TYPE_AP && keyidx) {
/*
* 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.
*/
if (net_ratelimit())
printk(KERN_DEBUG "%s: ignored Michael MIC error for "
"a frame with non-zero keyidx (%d)"
" (src %s)\n", dev->name, keyidx,
print_mac(mac, hdr->addr2));
goto ignore;
}
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)) {
if (net_ratelimit())
printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
"error for a frame that cannot be encrypted "
"(fc=0x%04x) (src %s)\n",
dev->name, rx->fc, print_mac(mac, hdr->addr2));
goto ignore;
}
mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr);
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,
ieee80211_rx_h_decrypt,
ieee80211_rx_h_sta_process,
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,
ieee80211_rx_h_amsdu,
ieee80211_rx_h_data,
ieee80211_rx_h_mgmt,
NULL
};
/* main receive path */
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);
switch (sdata->type) {
case IEEE80211_IF_TYPE_STA:
if (!bssid)
return 0;
if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
return 0;
rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
} else if (!multicast &&
compare_ether_addr(sdata->dev->dev_addr,
hdr->addr1) != 0) {
if (!(sdata->dev->flags & IFF_PROMISC))
return 0;
rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
}
break;
case IEEE80211_IF_TYPE_IBSS:
if (!bssid)
return 0;
if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
return 0;
rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
} else if (!multicast &&
compare_ether_addr(sdata->dev->dev_addr,
hdr->addr1) != 0) {
if (!(sdata->dev->flags & IFF_PROMISC))
return 0;
rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
} else if (!rx->sta)
rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
bssid, hdr->addr2);
break;
case IEEE80211_IF_TYPE_VLAN:
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)) {
if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
return 0;
rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
}
if (sdata->dev == sdata->local->mdev &&
!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
/* 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;
case IEEE80211_IF_TYPE_MNTR:
/* take everything */
break;
case IEEE80211_IF_TYPE_INVALID:
/* should never get here */
WARN_ON(1);
break;
}
return 1;
}
/*
* 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);
struct ieee80211_sub_if_data *sdata;
struct sta_info *sta;
struct ieee80211_hdr *hdr;
struct ieee80211_txrx_data rx;
u16 type;
int prepres;
struct ieee80211_sub_if_data *prev = NULL;
struct sk_buff *skb_new;
u8 *bssid;
int hdrlen;
/*
* 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.
*/
skb = ieee80211_rx_monitor(local, skb, status);
if (!skb) {
rcu_read_unlock();
return;
}
hdr = (struct ieee80211_hdr *) skb->data;
memset(&rx, 0, sizeof(rx));
rx.skb = skb;
rx.local = local;
rx.u.rx.status = status;
rx.fc = le16_to_cpu(hdr->frame_control);
type = rx.fc & IEEE80211_FCTL_FTYPE;
/*
* Drivers are required to align the payload data to a four-byte
* boundary, so the last two bits of the address where it starts
* may not be set. The header is required to be directly before
* the payload data, 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);
WARN_ON_ONCE(((unsigned long)(skb->data + hdrlen)) & 3);
if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT)
local->dot11ReceivedFragmentCount++;
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);
}
if ((status->flag & RX_FLAG_MMIC_ERROR)) {
ieee80211_rx_michael_mic_report(local->mdev, hdr, sta, &rx);
goto end;
}
if (unlikely(local->sta_sw_scanning || local->sta_hw_scanning))
rx.flags |= IEEE80211_TXRXD_RXIN_SCAN;
if (__ieee80211_invoke_rx_handlers(local, local->rx_pre_handlers, &rx,
sta) != TXRX_CONTINUE)
goto end;
skb = rx.skb;
if (sta && !(sta->flags & (WLAN_STA_WDS | WLAN_STA_ASSOC_AP)) &&
!atomic_read(&local->iff_promiscs) &&
!is_multicast_ether_addr(hdr->addr1)) {
rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
ieee80211_invoke_rx_handlers(local, local->rx_handlers, &rx,
rx.sta);
sta_info_put(sta);
rcu_read_unlock();
return;
}
bssid = ieee80211_get_bssid(hdr, skb->len);
list_for_each_entry_rcu(sdata, &local->interfaces, list) {
if (!netif_running(sdata->dev))
continue;
if (sdata->type == IEEE80211_IF_TYPE_MNTR)
continue;
rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
prepres = prepare_for_handlers(sdata, bssid, &rx, hdr);
/* prepare_for_handlers can change sta */
sta = rx.sta;
if (!prepres)
continue;
/*
* 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;
}
/*
* 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",
wiphy_name(local->hw.wiphy),
prev->dev->name);
continue;
}
rx.skb = skb_new;
rx.dev = prev->dev;
rx.sdata = prev;
ieee80211_invoke_rx_handlers(local, local->rx_handlers,
&rx, sta);
prev = sdata;
}
if (prev) {
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);
end:
rcu_read_unlock();
if (sta)
sta_info_put(sta);
}
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);
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