/*
* 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.
*
* utilities for mac80211
*/
#include <net/mac80211.h>
#include <linux/netdevice.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/etherdevice.h>
#include <linux/if_arp.h>
#include <linux/wireless.h>
#include <linux/bitmap.h>
#include <linux/crc32.h>
#include <net/net_namespace.h>
#include <net/cfg80211.h>
#include <net/rtnetlink.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
#include "rate.h"
#include "mesh.h"
#include "wme.h"
#include "led.h"
#include "wep.h"
/* privid for wiphys to determine whether they belong to us or not */
void *mac80211_wiphy_privid = &mac80211_wiphy_privid;
struct ieee80211_hw *wiphy_to_ieee80211_hw(struct wiphy *wiphy)
{
struct ieee80211_local *local;
BUG_ON(!wiphy);
local = wiphy_priv(wiphy);
return &local->hw;
}
EXPORT_SYMBOL(wiphy_to_ieee80211_hw);
u8 *ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len,
enum nl80211_iftype type)
{
__le16 fc = hdr->frame_control;
/* drop ACK/CTS frames and incorrect hdr len (ctrl) */
if (len < 16)
return NULL;
if (ieee80211_is_data(fc)) {
if (len < 24) /* drop incorrect hdr len (data) */
return NULL;
if (ieee80211_has_a4(fc))
return NULL;
if (ieee80211_has_tods(fc))
return hdr->addr1;
if (ieee80211_has_fromds(fc))
return hdr->addr2;
return hdr->addr3;
}
if (ieee80211_is_mgmt(fc)) {
if (len < 24) /* drop incorrect hdr len (mgmt) */
return NULL;
return hdr->addr3;
}
if (ieee80211_is_ctl(fc)) {
if(ieee80211_is_pspoll(fc))
return hdr->addr1;
if (ieee80211_is_back_req(fc)) {
switch (type) {
case NL80211_IFTYPE_STATION:
return hdr->addr2;
case NL80211_IFTYPE_AP:
case NL80211_IFTYPE_AP_VLAN:
return hdr->addr1;
default:
break; /* fall through to the return */
}
}
}
return NULL;
}
void ieee80211_tx_set_protected(struct ieee80211_tx_data *tx)
{
struct sk_buff *skb = tx->skb;
struct ieee80211_hdr *hdr;
do {
hdr = (struct ieee80211_hdr *) skb->data;
hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
} while ((skb = skb->next));
}
int ieee80211_frame_duration(struct ieee80211_local *local, size_t len,
int rate, int erp, int short_preamble)
{
int dur;
/* calculate duration (in microseconds, rounded up to next higher
* integer if it includes a fractional microsecond) to send frame of
* len bytes (does not include FCS) at the given rate. Duration will
* also include SIFS.
*
* rate is in 100 kbps, so divident is multiplied by 10 in the
* DIV_ROUND_UP() operations.
*/
if (local->hw.conf.channel->band == IEEE80211_BAND_5GHZ || erp) {
/*
* OFDM:
*
* N_DBPS = DATARATE x 4
* N_SYM = Ceiling((16+8xLENGTH+6) / N_DBPS)
* (16 = SIGNAL time, 6 = tail bits)
* TXTIME = T_PREAMBLE + T_SIGNAL + T_SYM x N_SYM + Signal Ext
*
* T_SYM = 4 usec
* 802.11a - 17.5.2: aSIFSTime = 16 usec
* 802.11g - 19.8.4: aSIFSTime = 10 usec +
* signal ext = 6 usec
*/
dur = 16; /* SIFS + signal ext */
dur += 16;