[linux-block.git] / net / mac80211 / util.c

/*
 * 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 "ieee80211_rate.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[] =
	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };

/* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
const unsigned char bridge_tunnel_header[] =
	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };

/* No encapsulation header if EtherType < 0x600 (=length) */
static const unsigned char eapol_header[] =
	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00, 0x88, 0x8e };


static int rate_list_match(const int *rate_list, int rate)
{
	int i;

	if (!rate_list)
		return 0;

	for (i = 0; rate_list[i] >= 0; i++)
		if (rate_list[i] == rate)
			return 1;

	return 0;
}

void ieee80211_prepare_rates(struct ieee80211_local *local,
			     struct ieee80211_hw_mode *mode)
{
	int i;

	for (i = 0; i < mode->num_rates; i++) {
		struct ieee80211_rate *rate = &mode->rates[i];

		rate->flags &= ~(IEEE80211_RATE_SUPPORTED |
				 IEEE80211_RATE_BASIC);

		if (local->supp_rates[mode->mode]) {
			if (!rate_list_match(local->supp_rates[mode->mode],
					     rate->rate))
				continue;
		}

		rate->flags |= IEEE80211_RATE_SUPPORTED;

		/* Use configured basic rate set if it is available. If not,
		 * use defaults that are sane for most cases. */
		if (local->basic_rates[mode->mode]) {
			if (rate_list_match(local->basic_rates[mode->mode],
					    rate->rate))
				rate->flags |= IEEE80211_RATE_BASIC;
		} else switch (mode->mode) {
		case MODE_IEEE80211A:
			if (rate->rate == 60 || rate->rate == 120 ||
			    rate->rate == 240)
				rate->flags |= IEEE80211_RATE_BASIC;
			break;
		case MODE_IEEE80211B:
			if (rate->rate == 10 || rate->rate == 20)
				rate->flags |= IEEE80211_RATE_BASIC;
			break;
		case MODE_IEEE80211G:
			if (rate->rate == 10 || rate->rate == 20 ||
			    rate->rate == 55 || rate->rate == 110)
				rate->flags |= IEEE80211_RATE_BASIC;
			break;
		case NUM_IEEE80211_MODES:
			/* not useful */
			break;
		}

		/* Set ERP and MANDATORY flags based on phymode */
		switch (mode->mode) {
		case MODE_IEEE80211A:
			if (rate->rate == 60 || rate->rate == 120 ||
			    rate->rate == 240)
				rate->flags |= IEEE80211_RATE_MANDATORY;
			break;
		case MODE_IEEE80211B:
			if (rate->rate == 10)
				rate->flags |= IEEE80211_RATE_MANDATORY;
			break;
		case MODE_IEEE80211G:
			if (rate->rate == 10 || rate->rate == 20 ||
			    rate->rate == 55 || rate->rate == 110 ||
			    rate->rate == 60 || rate->rate == 120 ||
			    rate->rate == 240)
				rate->flags |= IEEE80211_RATE_MANDATORY;
			break;
		case NUM_IEEE80211_MODES:
			/* not useful */
			break;
		}
		if (ieee80211_is_erp_rate(mode->mode, rate->rate))
			rate->flags |= IEEE80211_RATE_ERP;
	}
}

u8 *ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len)
{
	u16 fc;

	if (len < 24)
		return NULL;

	fc = le16_to_cpu(hdr->frame_control);

	switch (fc & IEEE80211_FCTL_FTYPE) {
	case IEEE80211_FTYPE_DATA:
		switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
		case IEEE80211_FCTL_TODS:
			return hdr->addr1;
		case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
			return NULL;
		case IEEE80211_FCTL_FROMDS:
			return hdr->addr2;
		case 0:
			return hdr->addr3;
		}
		break;
	case IEEE80211_FTYPE_MGMT:
		return hdr->addr3;
	case IEEE80211_FTYPE_CTL:
		if ((fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)
			return hdr->addr1;
		else
			return NULL;
	}

	return NULL;
}

int ieee80211_get_hdrlen(u16 fc)
{
	int hdrlen = 24;

	switch (fc & IEEE80211_FCTL_FTYPE) {
	case IEEE80211_FTYPE_DATA:
		if ((fc & IEEE80211_FCTL_FROMDS) && (fc & IEEE80211_FCTL_TODS))
			hdrlen = 30; /* Addr4 */
		/*
		 * The QoS Control field is two bytes and its presence is
		 * indicated by the IEEE80211_STYPE_QOS_DATA bit. Add 2 to
		 * hdrlen if that bit is set.
		 * This works by masking out the bit and shifting it to
		 * bit position 1 so the result has the value 0 or 2.
		 */
		hdrlen += (fc & IEEE80211_STYPE_QOS_DATA)
				>> (ilog2(IEEE80211_STYPE_QOS_DATA)-1);
		break;
	case IEEE80211_FTYPE_CTL:
		/*
		 * 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 & 0xE0) == 0xC0)
			hdrlen = 10;
		else
			hdrlen = 16;
		break;
	}

	return hdrlen;
}
EXPORT_SYMBOL(ieee80211_get_hdrlen);

int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
{
	const struct ieee80211_hdr *hdr = (const struct ieee80211_hdr *) skb->data;
	int hdrlen;

	if (unlikely(skb->len < 10))
		return 0;
	hdrlen = ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_control));
	if (unlikely(hdrlen > skb->len))
		return 0;
	return hdrlen;
}
EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);

int ieee80211_is_eapol(const struct sk_buff *skb, int hdrlen)
{
	if (unlikely(skb->len < 10))
		return 0;

	if (unlikely(skb->len >= hdrlen + sizeof(eapol_header) &&
		     memcmp(skb->data + hdrlen, eapol_header,
			    sizeof(eapol_header)) == 0))
		return 1;

	return 0;
}

void ieee80211_tx_set_iswep(struct ieee80211_txrx_data *tx)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;

	hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
	if (tx->u.tx.extra_frag) {
		struct ieee80211_hdr *fhdr;
		int i;
		for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
			fhdr = (struct ieee80211_hdr *)
				tx->u.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.phymode == MODE_IEEE80211A || 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, int if_id,
					size_t frame_len, int rate)
{
	struct ieee80211_local *local = hw_to_local(hw);
	struct net_device *bdev = dev_get_by_index(&init_net, if_id);
	struct ieee80211_sub_if_data *sdata;
	u16 dur;
	int erp;

	if (unlikely(!bdev))
		return 0;

	sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
	erp = ieee80211_is_erp_rate(hw->conf.phymode, rate);
	dur = ieee80211_frame_duration(local, frame_len, rate,
		       erp, sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE);

	dev_put(bdev);
	return cpu_to_le16(dur);
}
EXPORT_SYMBOL(ieee80211_generic_frame_duration);

__le16 ieee80211_rts_duration(struct ieee80211_hw *hw, int if_id,
			      size_t frame_len,
			      const struct ieee80211_tx_control *frame_txctl)
{
	struct ieee80211_local *local = hw_to_local(hw);
	struct ieee80211_rate *rate;
	struct net_device *bdev = dev_get_by_index(&init_net, if_id);
	struct ieee80211_sub_if_data *sdata;
	int short_preamble;
	int erp;
	u16 dur;

	if (unlikely(!bdev))
		return 0;

	sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
	short_preamble = sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE;

	rate = frame_txctl->rts_rate;
	erp = !!(rate->flags & IEEE80211_RATE_ERP);

	/* CTS duration */
	dur = ieee80211_frame_duration(local, 10, rate->rate,
				       erp, short_preamble);
	/* Data frame duration */
	dur += ieee80211_frame_duration(local, frame_len, rate->rate,
					erp, short_preamble);
	/* ACK duration */
	dur += ieee80211_frame_duration(local, 10, rate->rate,
					erp, short_preamble);

	dev_put(bdev);
	return cpu_to_le16(dur);
}
EXPORT_SYMBOL(ieee80211_rts_duration);

__le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw, int if_id,
				    size_t frame_len,
				    const struct ieee80211_tx_control *frame_txctl)
{
	struct ieee80211_local *local = hw_to_local(hw);
	struct ieee80211_rate *rate;
	struct net_device *bdev = dev_get_by_index(&init_net, if_id);
	struct ieee80211_sub_if_data *sdata;
	int short_preamble;
	int erp;
	u16 dur;

	if (unlikely(!bdev))
		return 0;

	sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
	short_preamble = sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE;

	rate = frame_txctl->rts_rate;
	erp = !!(rate->flags & IEEE80211_RATE_ERP);

	/* Data frame duration */
	dur = ieee80211_frame_duration(local, frame_len, rate->rate,
				       erp, short_preamble);
	if (!(frame_txctl->flags & IEEE80211_TXCTL_NO_ACK)) {
		/* ACK duration */
		dur += ieee80211_frame_duration(local, 10, rate->rate,
						erp, short_preamble);
	}

	dev_put(bdev);
	return cpu_to_le16(dur);
}
EXPORT_SYMBOL(ieee80211_ctstoself_duration);

struct ieee80211_rate *
ieee80211_get_rate(struct ieee80211_local *local, int phymode, int hw_rate)
{
	struct ieee80211_hw_mode *mode;
	int r;

	list_for_each_entry(mode, &local->modes_list, list) {
		if (mode->mode != phymode)
			continue;
		for (r = 0; r < mode->num_rates; r++) {
			struct ieee80211_rate *rate = &mode->rates[r];
			if (rate->val == hw_rate ||
			    (rate->flags & IEEE80211_RATE_PREAMBLE2 &&
			     rate->val2 == hw_rate))
				return rate;
		}
	}

	return NULL;
}

void ieee80211_wake_queue(struct ieee80211_hw *hw, int queue)
{
	struct ieee80211_local *local = hw_to_local(hw);

	if (test_and_clear_bit(IEEE80211_LINK_STATE_XOFF,
			       &local->state[queue])) {
		if (test_bit(IEEE80211_LINK_STATE_PENDING,
			     &local->state[queue]))
			tasklet_schedule(&local->tx_pending_tasklet);
		else
			if (!ieee80211_qdisc_installed(local->mdev)) {
				if (queue == 0)
					netif_wake_queue(local->mdev);
			} else
				__netif_schedule(local->mdev);
	}
}
EXPORT_SYMBOL(ieee80211_wake_queue);

void ieee80211_stop_queue(struct ieee80211_hw *hw, int queue)
{
	struct ieee80211_local *local = hw_to_local(hw);

	if (!ieee80211_qdisc_installed(local->mdev) && queue == 0)
		netif_stop_queue(local->mdev);
	set_bit(IEEE80211_LINK_STATE_XOFF, &local->state[queue]);
}
EXPORT_SYMBOL(ieee80211_stop_queue);

void ieee80211_start_queues(struct ieee80211_hw *hw)
{
	struct ieee80211_local *local = hw_to_local(hw);
	int i;

	for (i = 0; i < local->hw.queues; i++)
		clear_bit(IEEE80211_LINK_STATE_XOFF, &local->state[i]);
	if (!ieee80211_qdisc_installed(local->mdev))
		netif_start_queue(local->mdev);
}
EXPORT_SYMBOL(ieee80211_start_queues);

void ieee80211_stop_queues(struct ieee80211_hw *hw)
{
	int i;

	for (i = 0; i < hw->queues; i++)
		ieee80211_stop_queue(hw, i);
}
EXPORT_SYMBOL(ieee80211_stop_queues);

void ieee80211_wake_queues(struct ieee80211_hw *hw)
{
	int i;

	for (i = 0; i < hw->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,
							  int if_id),
					 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->type) {
		case IEEE80211_IF_TYPE_INVALID:
		case IEEE80211_IF_TYPE_MNTR:
		case IEEE80211_IF_TYPE_VLAN:
			continue;
		case IEEE80211_IF_TYPE_AP:
		case IEEE80211_IF_TYPE_STA:
		case IEEE80211_IF_TYPE_IBSS:
		case IEEE80211_IF_TYPE_WDS:
			break;
		}
		if (sdata->dev == local->mdev)
			continue;
		if (netif_running(sdata->dev))
			iterator(data, sdata->dev->dev_addr,
				 sdata->dev->ifindex);
	}

	rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(ieee80211_iterate_active_interfaces);
Commit	Line	Data
c2d1560a JB	1	/*
	2	* Copyright 2002-2005, Instant802 Networks, Inc.
	3	* Copyright 2005-2006, Devicescape Software, Inc.
	4	* Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
	5	* Copyright 2007 Johannes Berg <johannes@sipsolutions.net>
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*
	11	* utilities for mac80211
	12	*/
	13
	14	#include <net/mac80211.h>
	15	#include <linux/netdevice.h>
	16	#include <linux/types.h>
	17	#include <linux/slab.h>
	18	#include <linux/skbuff.h>
	19	#include <linux/etherdevice.h>
	20	#include <linux/if_arp.h>
	21	#include <linux/wireless.h>
	22	#include <linux/bitmap.h>
881d966b	23	#include <net/net_namespace.h>
c2d1560a	24	#include <net/cfg80211.h>
dabeb344	25	#include <net/rtnetlink.h>
c2d1560a JB	26
	27	#include "ieee80211_i.h"
	28	#include "ieee80211_rate.h"
	29	#include "wme.h"
	30
	31	/* privid for wiphys to determine whether they belong to us or not */
	32	void *mac80211_wiphy_privid = &mac80211_wiphy_privid;
	33
	34	/* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
	35	/* Ethernet-II snap header (RFC1042 for most EtherTypes) */
	36	const unsigned char rfc1042_header[] =
	37	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
	38
	39	/* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
	40	const unsigned char bridge_tunnel_header[] =
	41	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
	42
	43	/* No encapsulation header if EtherType < 0x600 (=length) */
	44	static const unsigned char eapol_header[] =
	45	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00, 0x88, 0x8e };
	46
	47
	48	static int rate_list_match(const int *rate_list, int rate)
	49	{
	50	int i;
	51
	52	if (!rate_list)
	53	return 0;
	54
	55	for (i = 0; rate_list[i] >= 0; i++)
	56	if (rate_list[i] == rate)
	57	return 1;
	58
	59	return 0;
	60	}
	61
	62	void ieee80211_prepare_rates(struct ieee80211_local *local,
	63	struct ieee80211_hw_mode *mode)
	64	{
	65	int i;
	66
	67	for (i = 0; i < mode->num_rates; i++) {
	68	struct ieee80211_rate *rate = &mode->rates[i];
	69
	70	rate->flags &= ~(IEEE80211_RATE_SUPPORTED \|
	71	IEEE80211_RATE_BASIC);
	72
	73	if (local->supp_rates[mode->mode]) {
	74	if (!rate_list_match(local->supp_rates[mode->mode],
	75	rate->rate))
	76	continue;
	77	}
	78
	79	rate->flags \|= IEEE80211_RATE_SUPPORTED;
	80
	81	/* Use configured basic rate set if it is available. If not,
	82	* use defaults that are sane for most cases. */
	83	if (local->basic_rates[mode->mode]) {
	84	if (rate_list_match(local->basic_rates[mode->mode],
	85	rate->rate))
	86	rate->flags \|= IEEE80211_RATE_BASIC;
	87	} else switch (mode->mode) {
	88	case MODE_IEEE80211A:
	89	if (rate->rate == 60 \|\| rate->rate == 120 \|\|
90	rate->rate == 240)
91	rate->flags \|= IEEE80211_RATE_BASIC;
92	break;
93	case MODE_IEEE80211B:
94	if (rate->rate == 10 \|\| rate->rate == 20)
95	rate->flags \|= IEEE80211_RATE_BASIC;
96	break;
c2d1560a JB	97	case MODE_IEEE80211G:
	98	if (rate->rate == 10 \|\| rate->rate == 20 \|\|
	99	rate->rate == 55 \|\| rate->rate == 110)
	100	rate->flags \|= IEEE80211_RATE_BASIC;
	101	break;
693d454d JB	102	case NUM_IEEE80211_MODES:
	103	/* not useful */
	104	break;
c2d1560a JB	105	}
	106
	107	/* Set ERP and MANDATORY flags based on phymode */
	108	switch (mode->mode) {
	109	case MODE_IEEE80211A:
	110	if (rate->rate == 60 \|\| rate->rate == 120 \|\|
	111	rate->rate == 240)
	112	rate->flags \|= IEEE80211_RATE_MANDATORY;
	113	break;
	114	case MODE_IEEE80211B:
	115	if (rate->rate == 10)
	116	rate->flags \|= IEEE80211_RATE_MANDATORY;
	117	break;
c2d1560a JB	118	case MODE_IEEE80211G:
	119	if (rate->rate == 10 \|\| rate->rate == 20 \|\|
	120	rate->rate == 55 \|\| rate->rate == 110 \|\|
	121	rate->rate == 60 \|\| rate->rate == 120 \|\|
	122	rate->rate == 240)
	123	rate->flags \|= IEEE80211_RATE_MANDATORY;
	124	break;
693d454d JB	125	case NUM_IEEE80211_MODES:
	126	/* not useful */
	127	break;
c2d1560a JB	128	}
	129	if (ieee80211_is_erp_rate(mode->mode, rate->rate))
	130	rate->flags \|= IEEE80211_RATE_ERP;
	131	}
	132	}
	133
	134	u8 ieee80211_get_bssid(struct ieee80211_hdr hdr, size_t len)
	135	{
	136	u16 fc;
	137
	138	if (len < 24)
	139	return NULL;
	140
	141	fc = le16_to_cpu(hdr->frame_control);
	142
	143	switch (fc & IEEE80211_FCTL_FTYPE) {
	144	case IEEE80211_FTYPE_DATA:
	145	switch (fc & (IEEE80211_FCTL_TODS \| IEEE80211_FCTL_FROMDS)) {
	146	case IEEE80211_FCTL_TODS:
	147	return hdr->addr1;
	148	case (IEEE80211_FCTL_TODS \| IEEE80211_FCTL_FROMDS):
	149	return NULL;
	150	case IEEE80211_FCTL_FROMDS:
	151	return hdr->addr2;
	152	case 0:
	153	return hdr->addr3;
	154	}
	155	break;
	156	case IEEE80211_FTYPE_MGMT:
	157	return hdr->addr3;
	158	case IEEE80211_FTYPE_CTL:
	159	if ((fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)
	160	return hdr->addr1;
	161	else
	162	return NULL;
	163	}
	164
	165	return NULL;
	166	}
	167
	168	int ieee80211_get_hdrlen(u16 fc)
	169	{
	170	int hdrlen = 24;
	171
	172	switch (fc & IEEE80211_FCTL_FTYPE) {
	173	case IEEE80211_FTYPE_DATA:
	174	if ((fc & IEEE80211_FCTL_FROMDS) && (fc & IEEE80211_FCTL_TODS))
	175	hdrlen = 30; /* Addr4 */
	176	/*
	177	* The QoS Control field is two bytes and its presence is
	178	* indicated by the IEEE80211_STYPE_QOS_DATA bit. Add 2 to
	179	* hdrlen if that bit is set.
	180	* This works by masking out the bit and shifting it to
	181	* bit position 1 so the result has the value 0 or 2.
	182	*/
	183	hdrlen += (fc & IEEE80211_STYPE_QOS_DATA)
	184	>> (ilog2(IEEE80211_STYPE_QOS_DATA)-1);
	185	break;
	186	case IEEE80211_FTYPE_CTL:
	187	/*
	188	* ACK and CTS are 10 bytes, all others 16. To see how
	189	* to get this condition consider
	190	* subtype mask: 0b0000000011110000 (0x00F0)
	191	* ACK subtype: 0b0000000011010000 (0x00D0)
192	* CTS subtype: 0b0000000011000000 (0x00C0)
193	* bits that matter: ^^^ (0x00E0)
194	* value of those: 0b0000000011000000 (0x00C0)
195	*/
196	if ((fc & 0xE0) == 0xC0)
197	hdrlen = 10;
198	else
199	hdrlen = 16;
200	break;
201	}
202
203	return hdrlen;
204	}
205	EXPORT_SYMBOL(ieee80211_get_hdrlen);
206
207	int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
208	{
209	const struct ieee80211_hdr hdr = (const struct ieee80211_hdr ) skb->data;
210	int hdrlen;
211
212	if (unlikely(skb->len < 10))
213	return 0;
214	hdrlen = ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_control));
215	if (unlikely(hdrlen > skb->len))
216	return 0;
217	return hdrlen;
218	}
219	EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);
220
76ee65bf	221	int ieee80211_is_eapol(const struct sk_buff *skb, int hdrlen)
c2d1560a	222	{
c2d1560a JB	223	if (unlikely(skb->len < 10))
	224	return 0;
	225
c2d1560a JB	226	if (unlikely(skb->len >= hdrlen + sizeof(eapol_header) &&
	227	memcmp(skb->data + hdrlen, eapol_header,
	228	sizeof(eapol_header)) == 0))
	229	return 1;
	230
	231	return 0;
	232	}
	233
	234	void ieee80211_tx_set_iswep(struct ieee80211_txrx_data *tx)
	235	{
	236	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) tx->skb->data;
	237
	238	hdr->frame_control \|= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
	239	if (tx->u.tx.extra_frag) {
	240	struct ieee80211_hdr *fhdr;
	241	int i;
	242	for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
	243	fhdr = (struct ieee80211_hdr *)
	244	tx->u.tx.extra_frag[i]->data;
	245	fhdr->frame_control \|= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
	246	}
	247	}
	248	}
	249
	250	int ieee80211_frame_duration(struct ieee80211_local *local, size_t len,
	251	int rate, int erp, int short_preamble)
	252	{
	253	int dur;
	254
	255	/* calculate duration (in microseconds, rounded up to next higher
	256	* integer if it includes a fractional microsecond) to send frame of
	257	* len bytes (does not include FCS) at the given rate. Duration will
	258	* also include SIFS.
	259	*
	260	* rate is in 100 kbps, so divident is multiplied by 10 in the
	261	* DIV_ROUND_UP() operations.
	262	*/
	263
b708e610	264	if (local->hw.conf.phymode == MODE_IEEE80211A \|\| erp) {
c2d1560a JB	265	/*
	266	* OFDM:
	267	*
	268	* N_DBPS = DATARATE x 4
	269	* N_SYM = Ceiling((16+8xLENGTH+6) / N_DBPS)
	270	* (16 = SIGNAL time, 6 = tail bits)
	271	* TXTIME = T_PREAMBLE + T_SIGNAL + T_SYM x N_SYM + Signal Ext
	272	*
	273	* T_SYM = 4 usec
	274	* 802.11a - 17.5.2: aSIFSTime = 16 usec
	275	* 802.11g - 19.8.4: aSIFSTime = 10 usec +
	276	* signal ext = 6 usec
	277	*/
c2d1560a JB	278	dur = 16; /* SIFS + signal ext */
	279	dur += 16; /* 17.3.2.3: T_PREAMBLE = 16 usec */
	280	dur += 4; /* 17.3.2.3: T_SIGNAL = 4 usec */
	281	dur += 4 * DIV_ROUND_UP((16 + 8 * (len + 4) + 6) * 10,
	282	4 * rate); /* T_SYM x N_SYM */
	283	} else {
	284	/*
	285	* 802.11b or 802.11g with 802.11b compatibility:
	286	* 18.3.4: TXTIME = PreambleLength + PLCPHeaderTime +
	287	* Ceiling(((LENGTH+PBCC)x8)/DATARATE). PBCC=0.
	288	*
	289	* 802.11 (DS): 15.3.3, 802.11b: 18.3.4
	290	* aSIFSTime = 10 usec
	291	* aPreambleLength = 144 usec or 72 usec with short preamble
	292	* aPLCPHeaderLength = 48 usec or 24 usec with short preamble
	293	*/
	294	dur = 10; /* aSIFSTime = 10 usec */
	295	dur += short_preamble ? (72 + 24) : (144 + 48);
	296
	297	dur += DIV_ROUND_UP(8 * (len + 4) * 10, rate);
	298	}
	299
	300	return dur;
	301	}
	302
	303	/* Exported duration function for driver use */
7e9ed188	304	__le16 ieee80211_generic_frame_duration(struct ieee80211_hw *hw, int if_id,
c2d1560a JB	305	size_t frame_len, int rate)
	306	{
	307	struct ieee80211_local *local = hw_to_local(hw);
881d966b	308	struct net_device *bdev = dev_get_by_index(&init_net, if_id);
7e9ed188	309	struct ieee80211_sub_if_data *sdata;
c2d1560a JB	310	u16 dur;
	311	int erp;
	312
7e9ed188 DD	313	if (unlikely(!bdev))
	314	return 0;
	315
	316	sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
c2d1560a JB	317	erp = ieee80211_is_erp_rate(hw->conf.phymode, rate);
c2d1560a JB	318	dur = ieee80211_frame_duration(local, frame_len, rate,
13262ffd	319	erp, sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE);
c2d1560a	320
7e9ed188	321	dev_put(bdev);
c2d1560a JB	322	return cpu_to_le16(dur);
	323	}
	324	EXPORT_SYMBOL(ieee80211_generic_frame_duration);
	325
7e9ed188	326	__le16 ieee80211_rts_duration(struct ieee80211_hw *hw, int if_id,
c2d1560a JB	327	size_t frame_len,
	328	const struct ieee80211_tx_control *frame_txctl)
	329	{
	330	struct ieee80211_local *local = hw_to_local(hw);
	331	struct ieee80211_rate *rate;
881d966b	332	struct net_device *bdev = dev_get_by_index(&init_net, if_id);
7e9ed188 DD	333	struct ieee80211_sub_if_data *sdata;
7e9ed188 DD	334	int short_preamble;
c2d1560a JB	335	int erp;
	336	u16 dur;
	337
7e9ed188 DD	338	if (unlikely(!bdev))
	339	return 0;
	340
	341	sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
13262ffd	342	short_preamble = sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE;
7e9ed188	343
c2d1560a JB	344	rate = frame_txctl->rts_rate;
	345	erp = !!(rate->flags & IEEE80211_RATE_ERP);
	346
	347	/* CTS duration */
	348	dur = ieee80211_frame_duration(local, 10, rate->rate,
	349	erp, short_preamble);
	350	/* Data frame duration */
	351	dur += ieee80211_frame_duration(local, frame_len, rate->rate,
	352	erp, short_preamble);
	353	/* ACK duration */
	354	dur += ieee80211_frame_duration(local, 10, rate->rate,
	355	erp, short_preamble);
	356
7e9ed188	357	dev_put(bdev);
c2d1560a JB	358	return cpu_to_le16(dur);
	359	}
	360	EXPORT_SYMBOL(ieee80211_rts_duration);
	361
7e9ed188	362	__le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw, int if_id,
c2d1560a JB	363	size_t frame_len,
	364	const struct ieee80211_tx_control *frame_txctl)
	365	{
	366	struct ieee80211_local *local = hw_to_local(hw);
	367	struct ieee80211_rate *rate;
881d966b	368	struct net_device *bdev = dev_get_by_index(&init_net, if_id);
7e9ed188 DD	369	struct ieee80211_sub_if_data *sdata;
7e9ed188 DD	370	int short_preamble;
c2d1560a JB	371	int erp;
	372	u16 dur;
	373
7e9ed188 DD	374	if (unlikely(!bdev))
	375	return 0;
	376
	377	sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
13262ffd	378	short_preamble = sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE;
7e9ed188	379
c2d1560a JB	380	rate = frame_txctl->rts_rate;
	381	erp = !!(rate->flags & IEEE80211_RATE_ERP);
	382
	383	/* Data frame duration */
	384	dur = ieee80211_frame_duration(local, frame_len, rate->rate,
	385	erp, short_preamble);
	386	if (!(frame_txctl->flags & IEEE80211_TXCTL_NO_ACK)) {
	387	/* ACK duration */
	388	dur += ieee80211_frame_duration(local, 10, rate->rate,
	389	erp, short_preamble);
	390	}
	391
7e9ed188	392	dev_put(bdev);
c2d1560a JB	393	return cpu_to_le16(dur);
	394	}
	395	EXPORT_SYMBOL(ieee80211_ctstoself_duration);
	396
	397	struct ieee80211_rate *
	398	ieee80211_get_rate(struct ieee80211_local *local, int phymode, int hw_rate)
	399	{
	400	struct ieee80211_hw_mode *mode;
	401	int r;
	402
	403	list_for_each_entry(mode, &local->modes_list, list) {
	404	if (mode->mode != phymode)
	405	continue;
	406	for (r = 0; r < mode->num_rates; r++) {
	407	struct ieee80211_rate *rate = &mode->rates[r];
	408	if (rate->val == hw_rate \|\|
	409	(rate->flags & IEEE80211_RATE_PREAMBLE2 &&
	410	rate->val2 == hw_rate))
	411	return rate;
	412	}
	413	}
	414
	415	return NULL;
	416	}
	417
	418	void ieee80211_wake_queue(struct ieee80211_hw *hw, int queue)
	419	{
	420	struct ieee80211_local *local = hw_to_local(hw);
	421
	422	if (test_and_clear_bit(IEEE80211_LINK_STATE_XOFF,
	423	&local->state[queue])) {
	424	if (test_bit(IEEE80211_LINK_STATE_PENDING,
	425	&local->state[queue]))
	426	tasklet_schedule(&local->tx_pending_tasklet);
	427	else
	428	if (!ieee80211_qdisc_installed(local->mdev)) {
	429	if (queue == 0)
	430	netif_wake_queue(local->mdev);
	431	} else
	432	__netif_schedule(local->mdev);
	433	}
	434	}
	435	EXPORT_SYMBOL(ieee80211_wake_queue);
	436
	437	void ieee80211_stop_queue(struct ieee80211_hw *hw, int queue)
	438	{
	439	struct ieee80211_local *local = hw_to_local(hw);
	440
	441	if (!ieee80211_qdisc_installed(local->mdev) && queue == 0)
	442	netif_stop_queue(local->mdev);
	443	set_bit(IEEE80211_LINK_STATE_XOFF, &local->state[queue]);
	444	}
	445	EXPORT_SYMBOL(ieee80211_stop_queue);
	446
	447	void ieee80211_start_queues(struct ieee80211_hw *hw)
	448	{
	449	struct ieee80211_local *local = hw_to_local(hw);
	450	int i;
	451
	452	for (i = 0; i < local->hw.queues; i++)
	453	clear_bit(IEEE80211_LINK_STATE_XOFF, &local->state[i]);
	454	if (!ieee80211_qdisc_installed(local->mdev))
	455	netif_start_queue(local->mdev);
	456	}
457	EXPORT_SYMBOL(ieee80211_start_queues);
458
459	void ieee80211_stop_queues(struct ieee80211_hw *hw)
460	{
461	int i;
462
463	for (i = 0; i < hw->queues; i++)
464	ieee80211_stop_queue(hw, i);
465	}
466	EXPORT_SYMBOL(ieee80211_stop_queues);
467
468	void ieee80211_wake_queues(struct ieee80211_hw *hw)
469	{
470	int i;
471
472	for (i = 0; i < hw->queues; i++)
473	ieee80211_wake_queue(hw, i);
474	}
475	EXPORT_SYMBOL(ieee80211_wake_queues);
dabeb344 JB	476
	477	void ieee80211_iterate_active_interfaces(struct ieee80211_hw *hw,
	478	void (iterator)(void data, u8 *mac,
	479	int if_id),
	480	void *data)
	481	{
	482	struct ieee80211_local *local = hw_to_local(hw);
	483	struct ieee80211_sub_if_data *sdata;
	484
e38bad47	485	rcu_read_lock();
dabeb344	486
e38bad47	487	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
dabeb344 JB	488	switch (sdata->type) {
	489	case IEEE80211_IF_TYPE_INVALID:
	490	case IEEE80211_IF_TYPE_MNTR:
	491	case IEEE80211_IF_TYPE_VLAN:
	492	continue;
	493	case IEEE80211_IF_TYPE_AP:
	494	case IEEE80211_IF_TYPE_STA:
	495	case IEEE80211_IF_TYPE_IBSS:
	496	case IEEE80211_IF_TYPE_WDS:
	497	break;
	498	}
	499	if (sdata->dev == local->mdev)
	500	continue;
	501	if (netif_running(sdata->dev))
	502	iterator(data, sdata->dev->dev_addr,
	503	sdata->dev->ifindex);
	504	}
e38bad47 JB	505
e38bad47 JB	506	rcu_read_unlock();
dabeb344 JB	507	}
dabeb344 JB	508	EXPORT_SYMBOL_GPL(ieee80211_iterate_active_interfaces);