[linux-2.6-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/cfg80211.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_ATHEROS_TURBO:
			if (rate->rate == 120 || rate->rate == 240 ||
			    rate->rate == 480)
				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;
		}

		/* 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_ATHEROS_TURBO:
			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;
		}
		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)
{
	const struct ieee80211_hdr *hdr;
	u16 fc;
	int hdrlen;

	if (unlikely(skb->len < 10))
		return 0;

	hdr = (const struct ieee80211_hdr *) skb->data;
	fc = le16_to_cpu(hdr->frame_control);

	if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
		return 0;

	hdrlen = ieee80211_get_hdrlen(fc);

	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 ||
	    local->hw.conf.phymode == MODE_ATHEROS_TURBO) {
		/*
		 * 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
		 */
		/* FIX: Atheros Turbo may have different (shorter) duration? */
		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,
					size_t frame_len, int rate)
{
	struct ieee80211_local *local = hw_to_local(hw);
	u16 dur;
	int erp;

	erp = ieee80211_is_erp_rate(hw->conf.phymode, rate);
	dur = ieee80211_frame_duration(local, frame_len, rate,
				       erp, local->short_preamble);

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

__le16 ieee80211_rts_duration(struct ieee80211_hw *hw,
			      size_t frame_len,
			      const struct ieee80211_tx_control *frame_txctl)
{
	struct ieee80211_local *local = hw_to_local(hw);
	struct ieee80211_rate *rate;
	int short_preamble = local->short_preamble;
	int erp;
	u16 dur;

	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);

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

__le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw,
				    size_t frame_len,
				    const struct ieee80211_tx_control *frame_txctl)
{
	struct ieee80211_local *local = hw_to_local(hw);
	struct ieee80211_rate *rate;
	int short_preamble = local->short_preamble;
	int erp;
	u16 dur;

	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);
	}

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