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linux/net/mac80211/rx.c
Bruno Randolf 601ae7f25a mac80211: make rx radiotap header more flexible 
use hw flags and rx flags to determine which fields are present in the header
and use all available information from the driver.

make sure radiotap header starts at a naturally aligned address (mod 8) for
all radiotap fields.

Signed-off-by: Bruno Randolf <br1@einfach.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-05-14 16:29:49 -04:00

2302 lines
63 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/jiffies.h>
#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 "led.h"
#include "mesh.h"
#include "wep.h"
#include "wpa.h"
#include "tkip.h"
#include "wme.h"
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);
/*
* 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)) &&
((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE)) !=
cpu_to_le16(IEEE80211_STYPE_BACK_REQ)))
return 1;
return 0;
}
static int
ieee80211_rx_radiotap_len(struct ieee80211_local *local,
struct ieee80211_rx_status *status)
{
int len;
/* always present fields */
len = sizeof(struct ieee80211_radiotap_header) + 9;
if (status->flag & RX_FLAG_TSFT)
len += 8;
if (local->hw.flags & IEEE80211_HW_SIGNAL_DB ||
local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
len += 1;
if (local->hw.flags & IEEE80211_HW_NOISE_DBM)
len += 1;
if (len & 1) /* padding for RX_FLAGS if necessary */
len++;
/* make sure radiotap starts at a naturally aligned address */
if (len % 8)
len = roundup(len, 8);
return len;
}
/**
* ieee80211_add_rx_radiotap_header - add radiotap header
*
* add a radiotap header containing all the fields which the hardware provided.
*/
static void
ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
struct sk_buff *skb,
struct ieee80211_rx_status *status,
struct ieee80211_rate *rate,
int rtap_len)
{
struct ieee80211_radiotap_header *rthdr;
unsigned char *pos;
rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
memset(rthdr, 0, rtap_len);
/* radiotap header, set always present flags */
rthdr->it_present =
cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
(1 << IEEE80211_RADIOTAP_RATE) |
(1 << IEEE80211_RADIOTAP_CHANNEL) |
(1 << IEEE80211_RADIOTAP_ANTENNA) |
(1 << IEEE80211_RADIOTAP_RX_FLAGS));
rthdr->it_len = cpu_to_le16(rtap_len);
pos = (unsigned char *)(rthdr+1);
/* the order of the following fields is important */
/* IEEE80211_RADIOTAP_TSFT */
if (status->flag & RX_FLAG_TSFT) {
*(__le64 *)pos = cpu_to_le64(status->mactime);
rthdr->it_present |=
cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
pos += 8;
}
/* IEEE80211_RADIOTAP_FLAGS */
if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
*pos |= IEEE80211_RADIOTAP_F_FCS;
pos++;
/* IEEE80211_RADIOTAP_RATE */
*pos = rate->bitrate / 5;
pos++;
/* IEEE80211_RADIOTAP_CHANNEL */
*(__le16 *)pos = cpu_to_le16(status->freq);
pos += 2;
if (status->band == IEEE80211_BAND_5GHZ)
*(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
IEEE80211_CHAN_5GHZ);
else
*(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_DYN |
IEEE80211_CHAN_2GHZ);
pos += 2;
/* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
*pos = status->signal;
rthdr->it_present |=
cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
pos++;
}
/* IEEE80211_RADIOTAP_DBM_ANTNOISE */
if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
*pos = status->noise;
rthdr->it_present |=
cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
pos++;
}
/* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
/* IEEE80211_RADIOTAP_ANTENNA */
*pos = status->antenna;
pos++;
/* IEEE80211_RADIOTAP_DB_ANTSIGNAL */
if (local->hw.flags & IEEE80211_HW_SIGNAL_DB) {
*pos = status->signal;
rthdr->it_present |=
cpu_to_le32(1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL);
pos++;
}
/* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
/* IEEE80211_RADIOTAP_RX_FLAGS */
/* ensure 2 byte alignment for the 2 byte field as required */
if ((pos - (unsigned char *)rthdr) & 1)
pos++;
/* FIXME: when radiotap gets a 'bad PLCP' flag use it here */
if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
*(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS);
pos += 2;
}
/*
* 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_rate *rate)
{
struct ieee80211_sub_if_data *sdata;
int needed_headroom = 0;
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 the radiotap header based on driver features */
needed_headroom = ieee80211_rx_radiotap_len(local, status);
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))
ieee80211_add_rx_radiotap_header(local, skb, status, rate,
needed_headroom);
skb_reset_mac_header(skb);
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->vif.type != IEEE80211_IF_TYPE_MNTR)
continue;
if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
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;
}
static void ieee80211_parse_qos(struct ieee80211_rx_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_RX_AMSDU;
else
rx->flags &= ~IEEE80211_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 */
}
}
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;
}
static void ieee80211_verify_ip_alignment(struct ieee80211_rx_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_RX_AMSDU)
hdrlen += ETH_HLEN;
WARN_ON_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3);
#endif
}
static u32 ieee80211_rx_load_stats(struct ieee80211_local *local,
struct sk_buff *skb,
struct ieee80211_rx_status *status,
struct ieee80211_rate *rate)
{
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 */
if (status->band == IEEE80211_BAND_5GHZ ||
(status->band == IEEE80211_BAND_5GHZ &&
rate->flags & IEEE80211_RATE_ERP_G))
hdrtime = CHAN_UTIL_HDR_SHORT;
else
hdrtime = CHAN_UTIL_HDR_LONG;
load = hdrtime;
if (!is_multicast_ether_addr(hdr->addr1))
load += hdrtime;
/* TODO: optimise again */
load += skb->len * CHAN_UTIL_RATE_LCM / rate->bitrate;
/* Divide channel_use by 8 to avoid wrapping around the counter */
load >>= CHAN_UTIL_SHIFT;
return load;
}
/* rx handlers */
static ieee80211_rx_result
ieee80211_rx_h_if_stats(struct ieee80211_rx_data *rx)
{
if (rx->sta)
rx->sta->channel_use_raw += rx->load;
rx->sdata->channel_use_raw += rx->load;
return RX_CONTINUE;
}
static ieee80211_rx_result
ieee80211_rx_h_passive_scan(struct ieee80211_rx_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->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->status)
!= RX_QUEUED)
dev_kfree_skb(skb);
return RX_QUEUED;
}
if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
/* scanning finished during invoking of handlers */
I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
return RX_DROP_UNUSABLE;
}
return RX_CONTINUE;
}
static ieee80211_rx_result
ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
{
int hdrlen = ieee80211_get_hdrlen(rx->fc);
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
#define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) {
if (!((rx->fc & IEEE80211_FCTL_FROMDS) &&
(rx->fc & IEEE80211_FCTL_TODS)))
return RX_DROP_MONITOR;
if (memcmp(hdr->addr4, rx->dev->dev_addr, ETH_ALEN) == 0)
return RX_DROP_MONITOR;
}
/* If there is not an established peer link and this is not a peer link
* establisment frame, beacon or probe, drop the frame.
*/
if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
struct ieee80211_mgmt *mgmt;
if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT)
return RX_DROP_MONITOR;
switch (rx->fc & IEEE80211_FCTL_STYPE) {
case IEEE80211_STYPE_ACTION:
mgmt = (struct ieee80211_mgmt *)hdr;
if (mgmt->u.action.category != PLINK_CATEGORY)
return RX_DROP_MONITOR;
/* fall through on else */
case IEEE80211_STYPE_PROBE_REQ:
case IEEE80211_STYPE_PROBE_RESP:
case IEEE80211_STYPE_BEACON:
return RX_CONTINUE;
break;
default:
return RX_DROP_MONITOR;
}
} else if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
is_multicast_ether_addr(hdr->addr1) &&
mesh_rmc_check(hdr->addr4, msh_h_get(hdr, hdrlen), rx->dev))
return RX_DROP_MONITOR;
#undef msh_h_get
return RX_CONTINUE;
}
static ieee80211_rx_result
ieee80211_rx_h_check(struct ieee80211_rx_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->queue] ==
hdr->seq_ctrl)) {
if (rx->flags & IEEE80211_RX_RA_MATCH) {
rx->local->dot11FrameDuplicateCount++;
rx->sta->num_duplicates++;
}
return RX_DROP_MONITOR;
} else
rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
}
if (unlikely(rx->skb->len < 16)) {
I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
return RX_DROP_MONITOR;
}
/* 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 (ieee80211_vif_is_mesh(&rx->sdata->vif))
return ieee80211_rx_mesh_check(rx);
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->vif.type != IEEE80211_IF_TYPE_IBSS &&
(!rx->sta || !test_sta_flags(rx->sta, 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_RX_RA_MATCH)) {
/* Drop IBSS frames and frames for other hosts
* silently. */
return RX_DROP_MONITOR;
}
return RX_DROP_MONITOR;
}
return RX_CONTINUE;
}
static ieee80211_rx_result
ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
{
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
int keyidx;
int hdrlen;
ieee80211_rx_result result = RX_DROP_UNUSABLE;
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 RX_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_RX_RA_MATCH))
return RX_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->status->flag & RX_FLAG_DECRYPTED) &&
(rx->status->flag & RX_FLAG_IV_STRIPPED))
return RX_CONTINUE;
hdrlen = ieee80211_get_hdrlen(rx->fc);
if (rx->skb->len < 8 + hdrlen)
return RX_DROP_UNUSABLE; /* 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 RX_DROP_MONITOR;
}
/* Check for weak IVs if possible */
if (rx->sta && rx->key->conf.alg == ALG_WEP &&
((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) &&
(!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
!(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->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 = sta->sdata;
if (sdata->bss)
atomic_inc(&sdata->bss->num_sta_ps);
set_and_clear_sta_flags(sta, WLAN_STA_PS, WLAN_STA_PSPOLL);
#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 = sta->sdata;
if (sdata->bss)
atomic_dec(&sdata->bss->num_sta_ps);
clear_sta_flags(sta, WLAN_STA_PS | WLAN_STA_PSPOLL);
if (!skb_queue_empty(&sta->ps_tx_buf))
sta_info_clear_tim_bit(sta);
#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_rx_result
ieee80211_rx_h_sta_process(struct ieee80211_rx_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 RX_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->vif.type == IEEE80211_IF_TYPE_IBSS) {
u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
IEEE80211_IF_TYPE_IBSS);
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->vif.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.
* Mesh beacons will update last_rx when if they are found to
* match the current local configuration when processed.
*/
sta->last_rx = jiffies;
}
if (!(rx->flags & IEEE80211_RX_RA_MATCH))
return RX_CONTINUE;
sta->rx_fragments++;
sta->rx_bytes += rx->skb->len;
sta->last_signal = rx->status->signal;
sta->last_qual = rx->status->qual;
sta->last_noise = rx->status->noise;
if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) {
/* Change STA power saving mode only in the end of a frame
* exchange sequence */
if (test_sta_flags(sta, WLAN_STA_PS) &&
!(rx->fc & IEEE80211_FCTL_PM))
rx->sent_ps_buffered += ap_sta_ps_end(dev, sta);
else if (!test_sta_flags(sta, 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 RX_QUEUED;
}
return RX_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 (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
__skb_queue_purge(&entry->skb_list);
continue;
}
return entry;
}
return NULL;
}
static ieee80211_rx_result
ieee80211_rx_h_defragment(struct ieee80211_rx_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->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->queue],
CCMP_PN_LEN);
}
return RX_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->queue, hdr);
if (!entry) {
I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
return RX_DROP_MONITOR;
}
/* 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 RX_DROP_UNUSABLE;
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->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 RX_DROP_UNUSABLE;
}
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 RX_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 RX_DROP_UNUSABLE;
}
}
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_RX_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 RX_CONTINUE;
}
static ieee80211_rx_result
ieee80211_rx_h_ps_poll(struct ieee80211_rx_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_RX_RA_MATCH)))
return RX_CONTINUE;
if ((sdata->vif.type != IEEE80211_IF_TYPE_AP) &&
(sdata->vif.type != IEEE80211_IF_TYPE_VLAN))
return RX_DROP_UNUSABLE;
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.
*/
set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
#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);
else
hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
dev_queue_xmit(skb);
if (no_pending_pkts)
sta_info_clear_tim_bit(rx->sta);
#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
} else if (!rx->sent_ps_buffered) {
/*
* FIXME: This can be the result of a race condition between
* us expiring a frame and the station polling for it.
* Should we send it a null-func frame indicating we
* have nothing buffered for it?
*/
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 RX_DROP that would
* count as an dropped frame. */
dev_kfree_skb(rx->skb);
return RX_QUEUED;
}
static ieee80211_rx_result
ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_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 RX_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 RX_CONTINUE;
}
static int
ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
{
if (unlikely(!rx->sta ||
!test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED))) {
#ifdef CONFIG_MAC80211_DEBUG
if (net_ratelimit())
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_rx_data *rx)
{
/*
* Pass through unencrypted frames if the hardware has
* decrypted them already.
*/
if (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)))
return -EACCES;
return 0;
}
static int
ieee80211_data_to_8023(struct ieee80211_rx_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);
if (ieee80211_vif_is_mesh(&sdata->vif)) {
int meshhdrlen = ieee80211_get_mesh_hdrlen(
(struct ieee80211s_hdr *) (skb->data + hdrlen));
/* Copy on cb:
* - mesh header: to be used for mesh forwarding
* decision. It will also be used as mesh header template at
* tx.c:ieee80211_subif_start_xmit() if interface
* type is mesh and skb->pkt_type == PACKET_OTHERHOST
* - ta: to be used if a RERR needs to be sent.
*/
memcpy(skb->cb, skb->data + hdrlen, meshhdrlen);
memcpy(MESH_PREQ(skb), hdr->addr2, ETH_ALEN);
hdrlen += meshhdrlen;
}
/* 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->vif.type != IEEE80211_IF_TYPE_AP &&
sdata->vif.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->vif.type != IEEE80211_IF_TYPE_WDS &&
sdata->vif.type != IEEE80211_IF_TYPE_MESH_POINT)) {
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->vif.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->vif.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;
}
/*
* requires that rx->skb is a frame with ethernet header
*/
static bool ieee80211_frame_allowed(struct ieee80211_rx_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
*/
static void
ieee80211_deliver_skb(struct ieee80211_rx_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);
struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
struct sta_info *dsta;
skb = rx->skb;
xmit_skb = NULL;
if (local->bridge_packets && (sdata->vif.type == IEEE80211_IF_TYPE_AP ||
sdata->vif.type == IEEE80211_IF_TYPE_VLAN) &&
(rx->flags & IEEE80211_RX_RA_MATCH)) {
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
*/
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 {
dsta = sta_info_get(local, skb->data);
if (dsta && dsta->sdata->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.
*/
xmit_skb = skb;
skb = NULL;
}
}
}
/* Mesh forwarding */
if (ieee80211_vif_is_mesh(&sdata->vif)) {
u8 *mesh_ttl = &((struct ieee80211s_hdr *)skb->cb)->ttl;
(*mesh_ttl)--;
if (is_multicast_ether_addr(skb->data)) {
if (*mesh_ttl > 0) {
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
xmit_skb->pkt_type = PACKET_OTHERHOST;
} else
IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.sta,
dropped_frames_ttl);
} else if (skb->pkt_type != PACKET_OTHERHOST &&
compare_ether_addr(dev->dev_addr, skb->data) != 0) {
if (*mesh_ttl == 0) {
IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.sta,
dropped_frames_ttl);
dev_kfree_skb(skb);
skb = NULL;
} else {
xmit_skb = skb;
xmit_skb->pkt_type = PACKET_OTHERHOST;
if (!(dev->flags & IFF_PROMISC))
skb = NULL;
}
}
}
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_reset_network_header(xmit_skb);
skb_reset_mac_header(xmit_skb);
dev_queue_xmit(xmit_skb);
}
}
static ieee80211_rx_result
ieee80211_rx_h_amsdu(struct ieee80211_rx_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 RX_CONTINUE;
if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
return RX_DROP_MONITOR;
if (!(rx->flags & IEEE80211_RX_AMSDU))
return RX_CONTINUE;
err = ieee80211_data_to_8023(rx);
if (unlikely(err))
return RX_DROP_UNUSABLE;
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 RX_DROP_UNUSABLE;
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 RX_DROP_UNUSABLE;
}
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 RX_DROP_UNUSABLE;
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 RX_DROP_UNUSABLE;
}
}
skb_reset_network_header(frame);
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 &&
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);
}
if (!ieee80211_frame_allowed(rx)) {
if (skb == frame) /* last frame */
return RX_DROP_UNUSABLE;
dev_kfree_skb(frame);
continue;
}
ieee80211_deliver_skb(rx);
}
return RX_QUEUED;
}
static ieee80211_rx_result
ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
{
struct net_device *dev = rx->dev;
u16 fc;
int err;
fc = rx->fc;
if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
return RX_CONTINUE;
if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
return RX_DROP_MONITOR;
err = ieee80211_data_to_8023(rx);
if (unlikely(err))
return RX_DROP_UNUSABLE;
if (!ieee80211_frame_allowed(rx))
return RX_DROP_MONITOR;
rx->skb->dev = dev;
dev->stats.rx_packets++;
dev->stats.rx_bytes += rx->skb->len;
ieee80211_deliver_skb(rx);
return RX_QUEUED;
}
static ieee80211_rx_result
ieee80211_rx_h_ctrl(struct ieee80211_rx_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 RX_CONTINUE;
if ((rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BACK_REQ) {
if (!rx->sta)
return RX_CONTINUE;
tid = le16_to_cpu(bar->control) >> 12;
if (rx->sta->ampdu_mlme.tid_state_rx[tid]
!= HT_AGG_STATE_OPERATIONAL)
return RX_CONTINUE;
tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
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 RX_DROP_UNUSABLE;
}
return RX_CONTINUE;
}
static ieee80211_rx_result
ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
{
struct ieee80211_sub_if_data *sdata;
if (!(rx->flags & IEEE80211_RX_RA_MATCH))
return RX_DROP_MONITOR;
sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
if ((sdata->vif.type == IEEE80211_IF_TYPE_STA ||
sdata->vif.type == IEEE80211_IF_TYPE_IBSS ||
sdata->vif.type == IEEE80211_IF_TYPE_MESH_POINT) &&
!(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->status);
else
return RX_DROP_MONITOR;
return RX_QUEUED;
}
static void ieee80211_rx_michael_mic_report(struct net_device *dev,
struct ieee80211_hdr *hdr,
struct ieee80211_rx_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 (!rx->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->vif.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;
}
/* TODO: use IEEE80211_RX_FRAGMENTED */
static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
{
struct ieee80211_sub_if_data *sdata;
struct ieee80211_local *local = rx->local;
struct ieee80211_rtap_hdr {
struct ieee80211_radiotap_header hdr;
u8 flags;
u8 rate;
__le16 chan_freq;
__le16 chan_flags;
} __attribute__ ((packed)) *rthdr;
struct sk_buff *skb = rx->skb, *skb2;
struct net_device *prev_dev = NULL;
struct ieee80211_rx_status *status = rx->status;
if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
goto out_free_skb;
if (skb_headroom(skb) < sizeof(*rthdr) &&
pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
goto out_free_skb;
rthdr = (void *)skb_push(skb, sizeof(*rthdr));
memset(rthdr, 0, sizeof(*rthdr));
rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
rthdr->hdr.it_present =
cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
(1 << IEEE80211_RADIOTAP_RATE) |
(1 << IEEE80211_RADIOTAP_CHANNEL));
rthdr->rate = rx->rate->bitrate / 5;
rthdr->chan_freq = cpu_to_le16(status->freq);
if (status->band == IEEE80211_BAND_5GHZ)
rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
IEEE80211_CHAN_5GHZ);
else
rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
IEEE80211_CHAN_2GHZ);
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->vif.type != IEEE80211_IF_TYPE_MNTR ||
!(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
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);
skb = NULL;
} else
goto out_free_skb;
rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
return;
out_free_skb:
dev_kfree_skb(skb);
}
typedef ieee80211_rx_result (*ieee80211_rx_handler)(struct ieee80211_rx_data *);
static 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_ctrl,
ieee80211_rx_h_mgmt,
NULL
};
static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
struct ieee80211_rx_data *rx,
struct sk_buff *skb)
{
ieee80211_rx_handler *handler;
ieee80211_rx_result res = RX_DROP_MONITOR;
rx->skb = skb;
rx->sdata = sdata;
rx->dev = sdata->dev;
for (handler = ieee80211_rx_handlers; *handler != NULL; handler++) {
res = (*handler)(rx);
switch (res) {
case RX_CONTINUE:
continue;
case RX_DROP_UNUSABLE:
case RX_DROP_MONITOR:
I802_DEBUG_INC(sdata->local->rx_handlers_drop);
if (rx->sta)
rx->sta->rx_dropped++;
break;
case RX_QUEUED:
I802_DEBUG_INC(sdata->local->rx_handlers_queued);
break;
}
break;
}
switch (res) {
case RX_CONTINUE:
case RX_DROP_MONITOR:
ieee80211_rx_cooked_monitor(rx);
break;
case RX_DROP_UNUSABLE:
dev_kfree_skb(rx->skb);
break;
}
}
/* main receive path */
static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
u8 *bssid, struct ieee80211_rx_data *rx,
struct ieee80211_hdr *hdr)
{
int multicast = is_multicast_ether_addr(hdr->addr1);
switch (sdata->vif.type) {
case IEEE80211_IF_TYPE_STA:
if (!bssid)
return 0;
if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
if (!(rx->flags & IEEE80211_RX_IN_SCAN))
return 0;
rx->flags &= ~IEEE80211_RX_RA_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_RX_RA_MATCH;
}
break;
case IEEE80211_IF_TYPE_IBSS:
if (!bssid)
return 0;
if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT &&
(rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BEACON)
return 1;
else if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
if (!(rx->flags & IEEE80211_RX_IN_SCAN))
return 0;
rx->flags &= ~IEEE80211_RX_RA_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_RX_RA_MATCH;
} else if (!rx->sta)
rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
bssid, hdr->addr2);
break;
case IEEE80211_IF_TYPE_MESH_POINT:
if (!multicast &&
compare_ether_addr(sdata->dev->dev_addr,
hdr->addr1) != 0) {
if (!(sdata->dev->flags & IFF_PROMISC))
return 0;
rx->flags &= ~IEEE80211_RX_RA_MATCH;
}
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_RX_IN_SCAN))
return 0;
rx->flags &= ~IEEE80211_RX_RA_MATCH;
}
if (sdata->dev == sdata->local->mdev &&
!(rx->flags & IEEE80211_RX_IN_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 actual Rx frames handler. as it blongs to Rx path it must
* be called with rcu_read_lock protection.
*/
static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
struct sk_buff *skb,
struct ieee80211_rx_status *status,
u32 load,
struct ieee80211_rate *rate)
{
struct ieee80211_local *local = hw_to_local(hw);
struct ieee80211_sub_if_data *sdata;
struct ieee80211_hdr *hdr;
struct ieee80211_rx_data rx;
u16 type;
int prepares;
struct ieee80211_sub_if_data *prev = NULL;
struct sk_buff *skb_new;
u8 *bssid;
hdr = (struct ieee80211_hdr *) skb->data;
memset(&rx, 0, sizeof(rx));
rx.skb = skb;
rx.local = local;
rx.status = status;
rx.load = load;
rx.rate = rate;
rx.fc = le16_to_cpu(hdr->frame_control);
type = rx.fc & IEEE80211_FCTL_FTYPE;
if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT)
local->dot11ReceivedFragmentCount++;
rx.sta = sta_info_get(local, hdr->addr2);
if (rx.sta) {
rx.sdata = rx.sta->sdata;
rx.dev = rx.sta->sdata->dev;
}
if ((status->flag & RX_FLAG_MMIC_ERROR)) {
ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx);
return;
}
if (unlikely(local->sta_sw_scanning || local->sta_hw_scanning))
rx.flags |= IEEE80211_RX_IN_SCAN;
ieee80211_parse_qos(&rx);
ieee80211_verify_ip_alignment(&rx);
skb = rx.skb;
list_for_each_entry_rcu(sdata, &local->interfaces, list) {
if (!netif_running(sdata->dev))
continue;
if (sdata->vif.type == IEEE80211_IF_TYPE_MNTR)
continue;
bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
rx.flags |= IEEE80211_RX_RA_MATCH;
prepares = prepare_for_handlers(sdata, bssid, &rx, hdr);
if (!prepares)
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.fc = le16_to_cpu(hdr->frame_control);
ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
prev = sdata;
}
if (prev) {
rx.fc = le16_to_cpu(hdr->frame_control);
ieee80211_invoke_rx_handlers(prev, &rx, skb);
} else
dev_kfree_skb(skb);
}
#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);
}
/*
* As it function blongs to Rx path it must be called with
* the proper rcu_read_lock protection for its flow.
*/
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;
struct ieee80211_supported_band *sband;
struct ieee80211_rate *rate;
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));
sband = local->hw.wiphy->bands[status.band];
rate = &sband->bitrates[status.rate_idx];
pkt_load = ieee80211_rx_load_stats(local,
tid_agg_rx->reorder_buf[index],
&status, rate);
__ieee80211_rx_handle_packet(hw,
tid_agg_rx->reorder_buf[index],
&status, pkt_load, rate);
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));
sband = local->hw.wiphy->bands[status.band];
rate = &sband->bitrates[status.rate_idx];
pkt_load = ieee80211_rx_load_stats(local,
tid_agg_rx->reorder_buf[index],
&status, rate);
__ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
&status, pkt_load, rate);
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;
}
static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
struct sk_buff *skb)
{
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;
if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
goto end_reorder;
tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
/* null data frames are excluded */
if (unlikely(fc & IEEE80211_STYPE_NULLFUNC))
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->sdata->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:
return ret;
}
/*
* 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;
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];
/*
* 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, rate);
if (!skb) {
rcu_read_unlock();
return;
}
pkt_load = ieee80211_rx_load_stats(local, skb, status, rate);
local->channel_use_raw += pkt_load;
if (!ieee80211_rx_reorder_ampdu(local, skb))
__ieee80211_rx_handle_packet(hw, skb, status, pkt_load, rate);
rcu_read_unlock();
}
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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