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DEFINITIONS
This source file includes following definitions.
- ieee80211_get_bssid
- ieee80211_hdrlen
- ieee80211_get_hdrlen_from_skb
- ieee80211_get_mesh_hdrlen
- ieee80211_tx_set_protected
- ieee80211_frame_duration
- ieee80211_generic_frame_duration
- ieee80211_rts_duration
- ieee80211_ctstoself_duration
- ieee80211_wake_queue
- ieee80211_stop_queue
- ieee80211_stop_queues
- ieee80211_queue_stopped
- ieee80211_wake_queues
- ieee80211_iterate_active_interfaces
- ieee80211_iterate_active_interfaces_atomic
- ieee802_11_parse_elems
- ieee80211_set_wmm_default
- ieee80211_tx_skb
- ieee80211_set_freq
- ieee80211_mandatory_rates
/*
* 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 <net/net_namespace.h>
#include <net/cfg80211.h>
#include <net/rtnetlink.h>
#include "ieee80211_i.h"
#include "rate.h"
#include "mesh.h"
#include "wme.h"
/* privid for wiphys to determine whether they belong to us or not */
void *mac80211_wiphy_privid = &mac80211_wiphy_privid;
/* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
/* Ethernet-II snap header (RFC1042 for most EtherTypes) */
const unsigned char rfc1042_header[] __aligned(2) =
{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
/* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
const unsigned char bridge_tunnel_header[] __aligned(2) =
{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
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;
}
unsigned int ieee80211_hdrlen(__le16 fc)
{
unsigned int hdrlen = 24;
if (ieee80211_is_data(fc)) {
if (ieee80211_has_a4(fc))
hdrlen = 30;
if (ieee80211_is_data_qos(fc))
hdrlen += IEEE80211_QOS_CTL_LEN;
goto out;
}
if (ieee80211_is_ctl(fc)) {
/*
* ACK and CTS are 10 bytes, all others 16. To see how
* to get this condition consider
* subtype mask: 0b0000000011110000 (0x00F0)
* ACK subtype: 0b0000000011010000 (0x00D0)
* CTS subtype: 0b0000000011000000 (0x00C0)
* bits that matter: ^^^ (0x00E0)
* value of those: 0b0000000011000000 (0x00C0)
*/
if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0))
hdrlen = 10;
else
hdrlen = 16;
}
out:
return hdrlen;
}
EXPORT_SYMBOL(ieee80211_hdrlen);
unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
{
const struct ieee80211_hdr *hdr = (const struct ieee80211_hdr *)skb->data;
unsigned int hdrlen;
if (unlikely(skb->len < 10))
return 0;
hdrlen = ieee80211_hdrlen(hdr->frame_control);
if (unlikely(hdrlen > skb->len))
return 0;
return hdrlen;
}
EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);
int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
{
int ae = meshhdr->flags & IEEE80211S_FLAGS_AE;
/* 7.1.3.5a.2 */
switch (ae) {
case 0:
return 6;
case 1:
return 12;
case 2:
return 18;
case 3:
return 24;
default:
return 6;
}
}
void ieee80211_tx_set_protected(struct ieee80211_tx_data *tx)
{
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
if (tx->extra_frag) {
struct ieee80211_hdr *fhdr;
int i;
for (i = 0; i < tx->num_extra_frag; i++) {
fhdr = (struct ieee80211_hdr *)
tx->extra_frag[i]->data;
fhdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
}
}
}
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; /* 17.3.2.3: T_PREAMBLE = 16 usec */
dur += 4; /* 17.3.2.3: T_SIGNAL = 4 usec */
dur += 4 * DIV_ROUND_UP((16 + 8 * (len + 4) + 6) * 10,
4 * rate); /* T_SYM x N_SYM */
} else {
/*
* 802.11b or 802.11g with 802.11b compatibility:
* 18.3.4: TXTIME = PreambleLength + PLCPHeaderTime +
* Ceiling(((LENGTH+PBCC)x8)/DATARATE). PBCC=0.
*
* 802.11 (DS): 15.3.3, 802.11b: 18.3.4
* aSIFSTime = 10 usec
* aPreambleLength = 144 usec or 72 usec with short preamble
* aPLCPHeaderLength = 48 usec or 24 usec with short preamble
*/
dur = 10; /* aSIFSTime = 10 usec */
dur += short_preamble ? (72 + 24) : (144 + 48);
dur += DIV_ROUND_UP(8 * (len + 4) * 10, rate);
}
return dur;
}
/* Exported duration function for driver use */
__le16 ieee80211_generic_frame_duration(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
size_t frame_len,
struct ieee80211_rate *rate)
{
struct ieee80211_local *local = hw_to_local(hw);
struct ieee80211_sub_if_data *sdata;
u16 dur;
int erp;
bool short_preamble = false;
erp = 0;
if (vif) {
sdata = vif_to_sdata(vif);
short_preamble = sdata->bss_conf.use_short_preamble;
if (sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
erp = rate->flags & IEEE80211_RATE_ERP_G;
}
dur = ieee80211_frame_duration(local, frame_len, rate->bitrate, erp,
short_preamble);
return cpu_to_le16(dur);
}
EXPORT_SYMBOL(ieee80211_generic_frame_duration);
__le16 ieee80211_rts_duration(struct ieee80211_hw *hw,
struct ieee80211_vif *vif, size_t frame_len,
const struct ieee80211_tx_info *frame_txctl)
{
struct ieee80211_local *local = hw_to_local(hw);
struct ieee80211_rate *rate;
struct ieee80211_sub_if_data *sdata;
bool short_preamble;
int erp;
u16 dur;
struct ieee80211_supported_band *sband;
sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
short_preamble = false;
rate = &sband->bitrates[frame_txctl->control.rts_cts_rate_idx];
erp = 0;
if (vif) {
sdata = vif_to_sdata(vif);
short_preamble = sdata->bss_conf.use_short_preamble;
if (sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
erp = rate->flags & IEEE80211_RATE_ERP_G;
}
/* CTS duration */
dur = ieee80211_frame_duration(local, 10, rate->bitrate,
erp, short_preamble);
/* Data frame duration */
dur += ieee80211_frame_duration(local, frame_len, rate->bitrate,
erp, short_preamble);
/* ACK duration */
dur += ieee80211_frame_duration(local, 10, rate->bitrate,
erp, short_preamble);
return cpu_to_le16(dur);
}
EXPORT_SYMBOL(ieee80211_rts_duration);
__le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
size_t frame_len,
const struct ieee80211_tx_info *frame_txctl)
{
struct ieee80211_local *local = hw_to_local(hw);
struct ieee80211_rate *rate;
struct ieee80211_sub_if_data *sdata;
bool short_preamble;
int erp;
u16 dur;
struct ieee80211_supported_band *sband;
sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
short_preamble = false;
rate = &sband->bitrates[frame_txctl->control.rts_cts_rate_idx];
erp = 0;
if (vif) {
sdata = vif_to_sdata(vif);
short_preamble = sdata->bss_conf.use_short_preamble;
if (sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
erp = rate->flags & IEEE80211_RATE_ERP_G;
}
/* Data frame duration */
dur = ieee80211_frame_duration(local, frame_len, rate->bitrate,
erp, short_preamble);
if (!(frame_txctl->flags & IEEE80211_TX_CTL_NO_ACK)) {
/* ACK duration */
dur += ieee80211_frame_duration(local, 10, rate->bitrate,
erp, short_preamble);
}
return cpu_to_le16(dur);
}
EXPORT_SYMBOL(ieee80211_ctstoself_duration);
void ieee80211_wake_queue(struct ieee80211_hw *hw, int queue)
{
struct ieee80211_local *local = hw_to_local(hw);
if (test_bit(queue, local->queues_pending)) {
set_bit(queue, local->queues_pending_run);
tasklet_schedule(&local->tx_pending_tasklet);
} else {
netif_wake_subqueue(local->mdev, queue);
}
}
EXPORT_SYMBOL(ieee80211_wake_queue);
void ieee80211_stop_queue(struct ieee80211_hw *hw, int queue)
{
struct ieee80211_local *local = hw_to_local(hw);
netif_stop_subqueue(local->mdev, queue);
}
EXPORT_SYMBOL(ieee80211_stop_queue);
void ieee80211_stop_queues(struct ieee80211_hw *hw)
{
int i;
for (i = 0; i < ieee80211_num_queues(hw); i++)
ieee80211_stop_queue(hw, i);
}
EXPORT_SYMBOL(ieee80211_stop_queues);
int ieee80211_queue_stopped(struct ieee80211_hw *hw, int queue)
{
struct ieee80211_local *local = hw_to_local(hw);
return __netif_subqueue_stopped(local->mdev, queue);
}
EXPORT_SYMBOL(ieee80211_queue_stopped);
void ieee80211_wake_queues(struct ieee80211_hw *hw)
{
int i;
for (i = 0; i < hw->queues + hw->ampdu_queues; i++)
ieee80211_wake_queue(hw, i);
}
EXPORT_SYMBOL(ieee80211_wake_queues);
void ieee80211_iterate_active_interfaces(
struct ieee80211_hw *hw,
void (*iterator)(void *data, u8 *mac,
struct ieee80211_vif *vif),
void *data)
{
struct ieee80211_local *local = hw_to_local(hw);
struct ieee80211_sub_if_data *sdata;
rtnl_lock();
list_for_each_entry(sdata, &local->interfaces, list) {
switch (sdata->vif.type) {
case __NL80211_IFTYPE_AFTER_LAST:
case NL80211_IFTYPE_UNSPECIFIED:
case NL80211_IFTYPE_MONITOR:
case NL80211_IFTYPE_AP_VLAN:
continue;
case NL80211_IFTYPE_AP:
case NL80211_IFTYPE_STATION:
case NL80211_IFTYPE_ADHOC:
case NL80211_IFTYPE_WDS:
case NL80211_IFTYPE_MESH_POINT:
break;
}
if (netif_running(sdata->dev))
iterator(data, sdata->dev->dev_addr,
&sdata->vif);
}
rtnl_unlock();
}
EXPORT_SYMBOL_GPL(ieee80211_iterate_active_interfaces);
void ieee80211_iterate_active_interfaces_atomic(
struct ieee80211_hw *hw,
void (*iterator)(void *data, u8 *mac,
struct ieee80211_vif *vif),
void *data)
{
struct ieee80211_local *local = hw_to_local(hw);
struct ieee80211_sub_if_data *sdata;
rcu_read_lock();
list_for_each_entry_rcu(sdata, &local->interfaces, list) {
switch (sdata->vif.type) {
case __NL80211_IFTYPE_AFTER_LAST:
case NL80211_IFTYPE_UNSPECIFIED:
case NL80211_IFTYPE_MONITOR:
case NL80211_IFTYPE_AP_VLAN:
continue;
case NL80211_IFTYPE_AP:
case NL80211_IFTYPE_STATION:
case NL80211_IFTYPE_ADHOC:
case NL80211_IFTYPE_WDS:
case NL80211_IFTYPE_MESH_POINT:
break;
}
if (netif_running(sdata->dev))
iterator(data, sdata->dev->dev_addr,
&sdata->vif);
}
rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(ieee80211_iterate_active_interfaces_atomic);
void ieee802_11_parse_elems(u8 *start, size_t len,
struct ieee802_11_elems *elems)
{
size_t left = len;
u8 *pos = start;
memset(elems, 0, sizeof(*elems));
elems->ie_start = start;
elems->total_len = len;
while (left >= 2) {
u8 id, elen;
id = *pos++;
elen = *pos++;
left -= 2;
if (elen > left)
return;
switch (id) {
case WLAN_EID_SSID:
elems->ssid = pos;
elems->ssid_len = elen;
break;
case WLAN_EID_SUPP_RATES:
elems->supp_rates = pos;
elems->supp_rates_len = elen;
break;
case WLAN_EID_FH_PARAMS:
elems->fh_params = pos;
elems->fh_params_len = elen;
break;
case WLAN_EID_DS_PARAMS:
elems->ds_params = pos;
elems->ds_params_len = elen;
break;
case WLAN_EID_CF_PARAMS:
elems->cf_params = pos;
elems->cf_params_len = elen;
break;
case WLAN_EID_TIM:
elems->tim = pos;
elems->tim_len = elen;
break;
case WLAN_EID_IBSS_PARAMS:
elems->ibss_params = pos;
elems->ibss_params_len = elen;
break;
case WLAN_EID_CHALLENGE:
elems->challenge = pos;
elems->challenge_len = elen;
break;
case WLAN_EID_WPA:
if (elen >= 4 && pos[0] == 0x00 && pos[1] == 0x50 &&
pos[2] == 0xf2) {
/* Microsoft OUI (00:50:F2) */
if (pos[3] == 1) {
/* OUI Type 1 - WPA IE */
elems->wpa = pos;
elems->wpa_len = elen;
} else if (elen >= 5 && pos[3] == 2) {
if (pos[4] == 0) {
elems->wmm_info = pos;
elems->wmm_info_len = elen;
} else if (pos[4] == 1) {
elems->wmm_param = pos;
elems->wmm_param_len = elen;
}
}
}
break;
case WLAN_EID_RSN:
elems->rsn = pos;
elems->rsn_len = elen;
break;
case WLAN_EID_ERP_INFO:
elems->erp_info = pos;
elems->erp_info_len = elen;
break;
case WLAN_EID_EXT_SUPP_RATES:
elems->ext_supp_rates = pos;
elems->ext_supp_rates_len = elen;
break;
case WLAN_EID_HT_CAPABILITY:
elems->ht_cap_elem = pos;
elems->ht_cap_elem_len = elen;
break;
case WLAN_EID_HT_EXTRA_INFO:
elems->ht_info_elem = pos;
elems->ht_info_elem_len = elen;
break;
case WLAN_EID_MESH_ID:
elems->mesh_id = pos;
elems->mesh_id_len = elen;
break;
case WLAN_EID_MESH_CONFIG:
elems->mesh_config = pos;
elems->mesh_config_len = elen;
break;
case WLAN_EID_PEER_LINK:
elems->peer_link = pos;
elems->peer_link_len = elen;
break;
case WLAN_EID_PREQ:
elems->preq = pos;
elems->preq_len = elen;
break;
case WLAN_EID_PREP:
elems->prep = pos;
elems->prep_len = elen;
break;
case WLAN_EID_PERR:
elems->perr = pos;
elems->perr_len = elen;
break;
case WLAN_EID_CHANNEL_SWITCH:
elems->ch_switch_elem = pos;
elems->ch_switch_elem_len = elen;
break;
case WLAN_EID_QUIET:
if (!elems->quiet_elem) {
elems->quiet_elem = pos;
elems->quiet_elem_len = elen;
}
elems->num_of_quiet_elem++;
break;
case WLAN_EID_COUNTRY:
elems->country_elem = pos;
elems->country_elem_len = elen;
break;
case WLAN_EID_PWR_CONSTRAINT:
elems->pwr_constr_elem = pos;
elems->pwr_constr_elem_len = elen;
break;
default:
break;
}
left -= elen;
pos += elen;
}
}
void ieee80211_set_wmm_default(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_tx_queue_params qparam;
int i;
if (!local->ops->conf_tx)
return;
memset(&qparam, 0, sizeof(qparam));
qparam.aifs = 2;
if (local->hw.conf.channel->band == IEEE80211_BAND_2GHZ &&
!(sdata->flags & IEEE80211_SDATA_OPERATING_GMODE))
qparam.cw_min = 31;
else
qparam.cw_min = 15;
qparam.cw_max = 1023;
qparam.txop = 0;
for (i = 0; i < local_to_hw(local)->queues; i++)
local->ops->conf_tx(local_to_hw(local), i, &qparam);
}
void ieee80211_tx_skb(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
int encrypt)
{
skb->dev = sdata->local->mdev;
skb_set_mac_header(skb, 0);
skb_set_network_header(skb, 0);
skb_set_transport_header(skb, 0);
skb->iif = sdata->dev->ifindex;
skb->do_not_encrypt = !encrypt;
dev_queue_xmit(skb);
}
int ieee80211_set_freq(struct ieee80211_sub_if_data *sdata, int freqMHz)
{
int ret = -EINVAL;
struct ieee80211_channel *chan;
struct ieee80211_local *local = sdata->local;
chan = ieee80211_get_channel(local->hw.wiphy, freqMHz);
if (chan && !(chan->flags & IEEE80211_CHAN_DISABLED)) {
if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
chan->flags & IEEE80211_CHAN_NO_IBSS) {
printk(KERN_DEBUG "%s: IBSS not allowed on frequency "
"%d MHz\n", sdata->dev->name, chan->center_freq);
return ret;
}
local->oper_channel = chan;
if (local->sw_scanning || local->hw_scanning)
ret = 0;
else
ret = ieee80211_hw_config(local);
rate_control_clear(local);
}
return ret;
}
u64 ieee80211_mandatory_rates(struct ieee80211_local *local,
enum ieee80211_band band)
{
struct ieee80211_supported_band *sband;
struct ieee80211_rate *bitrates;
u64 mandatory_rates;
enum ieee80211_rate_flags mandatory_flag;
int i;
sband = local->hw.wiphy->bands[band];
if (!sband) {
WARN_ON(1);
sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
}
if (band == IEEE80211_BAND_2GHZ)
mandatory_flag = IEEE80211_RATE_MANDATORY_B;
else
mandatory_flag = IEEE80211_RATE_MANDATORY_A;
bitrates = sband->bitrates;
mandatory_rates = 0;
for (i = 0; i < sband->n_bitrates; i++)
if (bitrates[i].flags & mandatory_flag)
mandatory_rates |= BIT(i);
return mandatory_rates;
}