tx.c 53 KB
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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.
 *
 *
 * Transmit and frame generation functions.
 */

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/etherdevice.h>
#include <linux/bitmap.h>
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#include <linux/rcupdate.h>
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#include <net/net_namespace.h>
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#include <net/ieee80211_radiotap.h>
#include <net/cfg80211.h>
#include <net/mac80211.h>
#include <asm/unaligned.h>

#include "ieee80211_i.h"
#include "ieee80211_led.h"
#include "wep.h"
#include "wpa.h"
#include "wme.h"
#include "ieee80211_rate.h"

#define IEEE80211_TX_OK		0
#define IEEE80211_TX_AGAIN	1
#define IEEE80211_TX_FRAG_AGAIN	2

/* misc utils */

static inline void ieee80211_include_sequence(struct ieee80211_sub_if_data *sdata,
					      struct ieee80211_hdr *hdr)
{
	/* Set the sequence number for this frame. */
	hdr->seq_ctrl = cpu_to_le16(sdata->sequence);

	/* Increase the sequence number. */
	sdata->sequence = (sdata->sequence + 0x10) & IEEE80211_SCTL_SEQ;
}

#ifdef CONFIG_MAC80211_LOWTX_FRAME_DUMP
static void ieee80211_dump_frame(const char *ifname, const char *title,
				 const struct sk_buff *skb)
{
	const struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
	u16 fc;
	int hdrlen;
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	DECLARE_MAC_BUF(mac);
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	printk(KERN_DEBUG "%s: %s (len=%d)", ifname, title, skb->len);
	if (skb->len < 4) {
		printk("\n");
		return;
	}

	fc = le16_to_cpu(hdr->frame_control);
	hdrlen = ieee80211_get_hdrlen(fc);
	if (hdrlen > skb->len)
		hdrlen = skb->len;
	if (hdrlen >= 4)
		printk(" FC=0x%04x DUR=0x%04x",
		       fc, le16_to_cpu(hdr->duration_id));
	if (hdrlen >= 10)
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		printk(" A1=%s", print_mac(mac, hdr->addr1));
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	if (hdrlen >= 16)
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		printk(" A2=%s", print_mac(mac, hdr->addr2));
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	if (hdrlen >= 24)
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		printk(" A3=%s", print_mac(mac, hdr->addr3));
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	if (hdrlen >= 30)
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		printk(" A4=%s", print_mac(mac, hdr->addr4));
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	printk("\n");
}
#else /* CONFIG_MAC80211_LOWTX_FRAME_DUMP */
static inline void ieee80211_dump_frame(const char *ifname, const char *title,
					struct sk_buff *skb)
{
}
#endif /* CONFIG_MAC80211_LOWTX_FRAME_DUMP */

static u16 ieee80211_duration(struct ieee80211_txrx_data *tx, int group_addr,
			      int next_frag_len)
{
	int rate, mrate, erp, dur, i;
	struct ieee80211_rate *txrate = tx->u.tx.rate;
	struct ieee80211_local *local = tx->local;
	struct ieee80211_hw_mode *mode = tx->u.tx.mode;

	erp = txrate->flags & IEEE80211_RATE_ERP;

	/*
	 * data and mgmt (except PS Poll):
	 * - during CFP: 32768
	 * - during contention period:
	 *   if addr1 is group address: 0
	 *   if more fragments = 0 and addr1 is individual address: time to
	 *      transmit one ACK plus SIFS
	 *   if more fragments = 1 and addr1 is individual address: time to
	 *      transmit next fragment plus 2 x ACK plus 3 x SIFS
	 *
	 * IEEE 802.11, 9.6:
	 * - control response frame (CTS or ACK) shall be transmitted using the
	 *   same rate as the immediately previous frame in the frame exchange
	 *   sequence, if this rate belongs to the PHY mandatory rates, or else
	 *   at the highest possible rate belonging to the PHY rates in the
	 *   BSSBasicRateSet
	 */

	if ((tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL) {
		/* TODO: These control frames are not currently sent by
		 * 80211.o, but should they be implemented, this function
		 * needs to be updated to support duration field calculation.
		 *
		 * RTS: time needed to transmit pending data/mgmt frame plus
		 *    one CTS frame plus one ACK frame plus 3 x SIFS
		 * CTS: duration of immediately previous RTS minus time
		 *    required to transmit CTS and its SIFS
		 * ACK: 0 if immediately previous directed data/mgmt had
		 *    more=0, with more=1 duration in ACK frame is duration
		 *    from previous frame minus time needed to transmit ACK
		 *    and its SIFS
		 * PS Poll: BIT(15) | BIT(14) | aid
		 */
		return 0;
	}

	/* data/mgmt */
	if (0 /* FIX: data/mgmt during CFP */)
		return 32768;

	if (group_addr) /* Group address as the destination - no ACK */
		return 0;

	/* Individual destination address:
	 * IEEE 802.11, Ch. 9.6 (after IEEE 802.11g changes)
	 * CTS and ACK frames shall be transmitted using the highest rate in
	 * basic rate set that is less than or equal to the rate of the
	 * immediately previous frame and that is using the same modulation
	 * (CCK or OFDM). If no basic rate set matches with these requirements,
	 * the highest mandatory rate of the PHY that is less than or equal to
	 * the rate of the previous frame is used.
	 * Mandatory rates for IEEE 802.11g PHY: 1, 2, 5.5, 11, 6, 12, 24 Mbps
	 */
	rate = -1;
	mrate = 10; /* use 1 Mbps if everything fails */
	for (i = 0; i < mode->num_rates; i++) {
		struct ieee80211_rate *r = &mode->rates[i];
		if (r->rate > txrate->rate)
			break;

		if (IEEE80211_RATE_MODULATION(txrate->flags) !=
		    IEEE80211_RATE_MODULATION(r->flags))
			continue;

		if (r->flags & IEEE80211_RATE_BASIC)
			rate = r->rate;
		else if (r->flags & IEEE80211_RATE_MANDATORY)
			mrate = r->rate;
	}
	if (rate == -1) {
		/* No matching basic rate found; use highest suitable mandatory
		 * PHY rate */
		rate = mrate;
	}

	/* Time needed to transmit ACK
	 * (10 bytes + 4-byte FCS = 112 bits) plus SIFS; rounded up
	 * to closest integer */

	dur = ieee80211_frame_duration(local, 10, rate, erp,
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		       tx->sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE);
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	if (next_frag_len) {
		/* Frame is fragmented: duration increases with time needed to
		 * transmit next fragment plus ACK and 2 x SIFS. */
		dur *= 2; /* ACK + SIFS */
		/* next fragment */
		dur += ieee80211_frame_duration(local, next_frag_len,
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				txrate->rate, erp,
				tx->sdata->flags &
					IEEE80211_SDATA_SHORT_PREAMBLE);
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	}

	return dur;
}

static inline int __ieee80211_queue_stopped(const struct ieee80211_local *local,
					    int queue)
{
	return test_bit(IEEE80211_LINK_STATE_XOFF, &local->state[queue]);
}

static inline int __ieee80211_queue_pending(const struct ieee80211_local *local,
					    int queue)
{
	return test_bit(IEEE80211_LINK_STATE_PENDING, &local->state[queue]);
}

static int inline is_ieee80211_device(struct net_device *dev,
				      struct net_device *master)
{
	return (wdev_priv(dev->ieee80211_ptr) ==
		wdev_priv(master->ieee80211_ptr));
}

/* tx handlers */

static ieee80211_txrx_result
ieee80211_tx_h_check_assoc(struct ieee80211_txrx_data *tx)
{
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
	struct sk_buff *skb = tx->skb;
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
	u32 sta_flags;

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	if (unlikely(tx->flags & IEEE80211_TXRXD_TX_INJECTED))
		return TXRX_CONTINUE;

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	if (unlikely(tx->local->sta_sw_scanning) &&
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	    ((tx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
	     (tx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PROBE_REQ))
		return TXRX_DROP;

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	if (tx->flags & IEEE80211_TXRXD_TXPS_BUFFERED)
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		return TXRX_CONTINUE;

	sta_flags = tx->sta ? tx->sta->flags : 0;

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	if (likely(tx->flags & IEEE80211_TXRXD_TXUNICAST)) {
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		if (unlikely(!(sta_flags & WLAN_STA_ASSOC) &&
			     tx->sdata->type != IEEE80211_IF_TYPE_IBSS &&
			     (tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)) {
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
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			DECLARE_MAC_BUF(mac);
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			printk(KERN_DEBUG "%s: dropped data frame to not "
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			       "associated station %s\n",
			       tx->dev->name, print_mac(mac, hdr->addr1));
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#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
			I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc);
			return TXRX_DROP;
		}
	} else {
		if (unlikely((tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
			     tx->local->num_sta == 0 &&
			     tx->sdata->type != IEEE80211_IF_TYPE_IBSS)) {
			/*
			 * No associated STAs - no need to send multicast
			 * frames.
			 */
			return TXRX_DROP;
		}
		return TXRX_CONTINUE;
	}

	return TXRX_CONTINUE;
}

static ieee80211_txrx_result
ieee80211_tx_h_sequence(struct ieee80211_txrx_data *tx)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;

	if (ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_control)) >= 24)
		ieee80211_include_sequence(tx->sdata, hdr);

	return TXRX_CONTINUE;
}

/* This function is called whenever the AP is about to exceed the maximum limit
 * of buffered frames for power saving STAs. This situation should not really
 * happen often during normal operation, so dropping the oldest buffered packet
 * from each queue should be OK to make some room for new frames. */
static void purge_old_ps_buffers(struct ieee80211_local *local)
{
	int total = 0, purged = 0;
	struct sk_buff *skb;
	struct ieee80211_sub_if_data *sdata;
	struct sta_info *sta;

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	/*
	 * virtual interfaces are protected by RCU
	 */
	rcu_read_lock();

	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
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		struct ieee80211_if_ap *ap;
		if (sdata->dev == local->mdev ||
		    sdata->type != IEEE80211_IF_TYPE_AP)
			continue;
		ap = &sdata->u.ap;
		skb = skb_dequeue(&ap->ps_bc_buf);
		if (skb) {
			purged++;
			dev_kfree_skb(skb);
		}
		total += skb_queue_len(&ap->ps_bc_buf);
	}
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	rcu_read_unlock();
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	read_lock_bh(&local->sta_lock);
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	list_for_each_entry(sta, &local->sta_list, list) {
		skb = skb_dequeue(&sta->ps_tx_buf);
		if (skb) {
			purged++;
			dev_kfree_skb(skb);
		}
		total += skb_queue_len(&sta->ps_tx_buf);
	}
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	read_unlock_bh(&local->sta_lock);
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	local->total_ps_buffered = total;
	printk(KERN_DEBUG "%s: PS buffers full - purged %d frames\n",
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	       wiphy_name(local->hw.wiphy), purged);
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}

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static ieee80211_txrx_result
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ieee80211_tx_h_multicast_ps_buf(struct ieee80211_txrx_data *tx)
{
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	/*
	 * broadcast/multicast frame
	 *
	 * If any of the associated stations is in power save mode,
	 * the frame is buffered to be sent after DTIM beacon frame.
	 * This is done either by the hardware or us.
	 */

	/* not AP/IBSS or ordered frame */
	if (!tx->sdata->bss || (tx->fc & IEEE80211_FCTL_ORDER))
		return TXRX_CONTINUE;

	/* no stations in PS mode */
	if (!atomic_read(&tx->sdata->bss->num_sta_ps))
		return TXRX_CONTINUE;

	/* buffered in mac80211 */
	if (tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING) {
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		if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
			purge_old_ps_buffers(tx->local);
		if (skb_queue_len(&tx->sdata->bss->ps_bc_buf) >=
		    AP_MAX_BC_BUFFER) {
			if (net_ratelimit()) {
				printk(KERN_DEBUG "%s: BC TX buffer full - "
				       "dropping the oldest frame\n",
				       tx->dev->name);
			}
			dev_kfree_skb(skb_dequeue(&tx->sdata->bss->ps_bc_buf));
		} else
			tx->local->total_ps_buffered++;
		skb_queue_tail(&tx->sdata->bss->ps_bc_buf, tx->skb);
		return TXRX_QUEUED;
	}

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	/* buffered in hardware */
	tx->u.tx.control->flags |= IEEE80211_TXCTL_SEND_AFTER_DTIM;

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	return TXRX_CONTINUE;
}

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static ieee80211_txrx_result
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ieee80211_tx_h_unicast_ps_buf(struct ieee80211_txrx_data *tx)
{
	struct sta_info *sta = tx->sta;
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	DECLARE_MAC_BUF(mac);
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	if (unlikely(!sta ||
		     ((tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT &&
		      (tx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PROBE_RESP)))
		return TXRX_CONTINUE;

	if (unlikely((sta->flags & WLAN_STA_PS) && !sta->pspoll)) {
		struct ieee80211_tx_packet_data *pkt_data;
#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
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		printk(KERN_DEBUG "STA %s aid %d: PS buffer (entries "
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		       "before %d)\n",
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		       print_mac(mac, sta->addr), sta->aid,
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		       skb_queue_len(&sta->ps_tx_buf));
#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
		sta->flags |= WLAN_STA_TIM;
		if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
			purge_old_ps_buffers(tx->local);
		if (skb_queue_len(&sta->ps_tx_buf) >= STA_MAX_TX_BUFFER) {
			struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf);
			if (net_ratelimit()) {
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				printk(KERN_DEBUG "%s: STA %s TX "
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				       "buffer full - dropping oldest frame\n",
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				       tx->dev->name, print_mac(mac, sta->addr));
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			}
			dev_kfree_skb(old);
		} else
			tx->local->total_ps_buffered++;
		/* Queue frame to be sent after STA sends an PS Poll frame */
		if (skb_queue_empty(&sta->ps_tx_buf)) {
			if (tx->local->ops->set_tim)
				tx->local->ops->set_tim(local_to_hw(tx->local),
						       sta->aid, 1);
			if (tx->sdata->bss)
				bss_tim_set(tx->local, tx->sdata->bss, sta->aid);
		}
		pkt_data = (struct ieee80211_tx_packet_data *)tx->skb->cb;
		pkt_data->jiffies = jiffies;
		skb_queue_tail(&sta->ps_tx_buf, tx->skb);
		return TXRX_QUEUED;
	}
#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
	else if (unlikely(sta->flags & WLAN_STA_PS)) {
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		printk(KERN_DEBUG "%s: STA %s in PS mode, but pspoll "
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		       "set -> send frame\n", tx->dev->name,
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		       print_mac(mac, sta->addr));
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	}
#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
	sta->pspoll = 0;

	return TXRX_CONTINUE;
}

static ieee80211_txrx_result
ieee80211_tx_h_ps_buf(struct ieee80211_txrx_data *tx)
{
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	if (unlikely(tx->flags & IEEE80211_TXRXD_TXPS_BUFFERED))
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		return TXRX_CONTINUE;

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	if (tx->flags & IEEE80211_TXRXD_TXUNICAST)
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		return ieee80211_tx_h_unicast_ps_buf(tx);
	else
		return ieee80211_tx_h_multicast_ps_buf(tx);
}

static ieee80211_txrx_result
ieee80211_tx_h_select_key(struct ieee80211_txrx_data *tx)
{
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	struct ieee80211_key *key;
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	u16 fc = tx->fc;
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	if (unlikely(tx->u.tx.control->flags & IEEE80211_TXCTL_DO_NOT_ENCRYPT))
		tx->key = NULL;
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	else if (tx->sta && (key = rcu_dereference(tx->sta->key)))
		tx->key = key;
	else if ((key = rcu_dereference(tx->sdata->default_key)))
		tx->key = key;
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	else if (tx->sdata->drop_unencrypted &&
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		 !(tx->u.tx.control->flags & IEEE80211_TXCTL_EAPOL_FRAME) &&
		 !(tx->flags & IEEE80211_TXRXD_TX_INJECTED)) {
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		I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
		return TXRX_DROP;
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	} else
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		tx->key = NULL;

	if (tx->key) {
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		u16 ftype, stype;

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		tx->key->tx_rx_count++;
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		/* TODO: add threshold stuff again */
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		switch (tx->key->conf.alg) {
		case ALG_WEP:
			ftype = fc & IEEE80211_FCTL_FTYPE;
			stype = fc & IEEE80211_FCTL_STYPE;

			if (ftype == IEEE80211_FTYPE_MGMT &&
			    stype == IEEE80211_STYPE_AUTH)
				break;
		case ALG_TKIP:
		case ALG_CCMP:
			if (!WLAN_FC_DATA_PRESENT(fc))
				tx->key = NULL;
			break;
		}
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	}

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	if (!tx->key || !(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
		tx->u.tx.control->flags |= IEEE80211_TXCTL_DO_NOT_ENCRYPT;

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	return TXRX_CONTINUE;
}

static ieee80211_txrx_result
ieee80211_tx_h_fragment(struct ieee80211_txrx_data *tx)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
	size_t hdrlen, per_fragm, num_fragm, payload_len, left;
	struct sk_buff **frags, *first, *frag;
	int i;
	u16 seq;
	u8 *pos;
	int frag_threshold = tx->local->fragmentation_threshold;

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	if (!(tx->flags & IEEE80211_TXRXD_FRAGMENTED))
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		return TXRX_CONTINUE;

	first = tx->skb;

	hdrlen = ieee80211_get_hdrlen(tx->fc);
	payload_len = first->len - hdrlen;
	per_fragm = frag_threshold - hdrlen - FCS_LEN;
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	num_fragm = DIV_ROUND_UP(payload_len, per_fragm);
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	frags = kzalloc(num_fragm * sizeof(struct sk_buff *), GFP_ATOMIC);
	if (!frags)
		goto fail;

	hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
	seq = le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ;
	pos = first->data + hdrlen + per_fragm;
	left = payload_len - per_fragm;
	for (i = 0; i < num_fragm - 1; i++) {
		struct ieee80211_hdr *fhdr;
		size_t copylen;

		if (left <= 0)
			goto fail;

		/* reserve enough extra head and tail room for possible
		 * encryption */
		frag = frags[i] =
			dev_alloc_skb(tx->local->tx_headroom +
				      frag_threshold +
				      IEEE80211_ENCRYPT_HEADROOM +
				      IEEE80211_ENCRYPT_TAILROOM);
		if (!frag)
			goto fail;
		/* Make sure that all fragments use the same priority so
		 * that they end up using the same TX queue */
		frag->priority = first->priority;
		skb_reserve(frag, tx->local->tx_headroom +
				  IEEE80211_ENCRYPT_HEADROOM);
		fhdr = (struct ieee80211_hdr *) skb_put(frag, hdrlen);
		memcpy(fhdr, first->data, hdrlen);
		if (i == num_fragm - 2)
			fhdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREFRAGS);
		fhdr->seq_ctrl = cpu_to_le16(seq | ((i + 1) & IEEE80211_SCTL_FRAG));
		copylen = left > per_fragm ? per_fragm : left;
		memcpy(skb_put(frag, copylen), pos, copylen);

		pos += copylen;
		left -= copylen;
	}
	skb_trim(first, hdrlen + per_fragm);

	tx->u.tx.num_extra_frag = num_fragm - 1;
	tx->u.tx.extra_frag = frags;

	return TXRX_CONTINUE;

 fail:
	printk(KERN_DEBUG "%s: failed to fragment frame\n", tx->dev->name);
	if (frags) {
		for (i = 0; i < num_fragm - 1; i++)
			if (frags[i])
				dev_kfree_skb(frags[i]);
		kfree(frags);
	}
	I802_DEBUG_INC(tx->local->tx_handlers_drop_fragment);
	return TXRX_DROP;
}

static ieee80211_txrx_result
566
ieee80211_tx_h_encrypt(struct ieee80211_txrx_data *tx)
567
{
568
	if (!tx->key)
569
570
		return TXRX_CONTINUE;

571
572
573
574
575
576
577
	switch (tx->key->conf.alg) {
	case ALG_WEP:
		return ieee80211_crypto_wep_encrypt(tx);
	case ALG_TKIP:
		return ieee80211_crypto_tkip_encrypt(tx);
	case ALG_CCMP:
		return ieee80211_crypto_ccmp_encrypt(tx);
578
579
	}

580
581
582
	/* not reached */
	WARN_ON(1);
	return TXRX_DROP;
583
584
585
586
587
}

static ieee80211_txrx_result
ieee80211_tx_h_rate_ctrl(struct ieee80211_txrx_data *tx)
{
588
	struct rate_selection rsel;
589

590
	if (likely(!tx->u.tx.rate)) {
591
592
593
		rate_control_get_rate(tx->dev, tx->u.tx.mode, tx->skb, &rsel);
		tx->u.tx.rate = rsel.rate;
		if (unlikely(rsel.probe != NULL)) {
594
595
596
597
			tx->u.tx.control->flags |=
				IEEE80211_TXCTL_RATE_CTRL_PROBE;
			tx->flags |= IEEE80211_TXRXD_TXPROBE_LAST_FRAG;
			tx->u.tx.control->alt_retry_rate = tx->u.tx.rate->val;
598
			tx->u.tx.rate = rsel.probe;
599
600
601
602
603
604
		} else
			tx->u.tx.control->alt_retry_rate = -1;

		if (!tx->u.tx.rate)
			return TXRX_DROP;
	} else
605
		tx->u.tx.control->alt_retry_rate = -1;
606

607
	if (tx->u.tx.mode->mode == MODE_IEEE80211G &&
608
	    (tx->sdata->flags & IEEE80211_SDATA_USE_PROTECTION) &&
609
	    (tx->flags & IEEE80211_TXRXD_FRAGMENTED) && rsel.nonerp) {
610
		tx->u.tx.last_frag_rate = tx->u.tx.rate;
611
		if (rsel.probe)
612
613
614
			tx->flags &= ~IEEE80211_TXRXD_TXPROBE_LAST_FRAG;
		else
			tx->flags |= IEEE80211_TXRXD_TXPROBE_LAST_FRAG;
615
616
		tx->u.tx.rate = rsel.nonerp;
		tx->u.tx.control->rate = rsel.nonerp;
617
618
619
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621
622
623
624
625
626
627
628
629
630
		tx->u.tx.control->flags &= ~IEEE80211_TXCTL_RATE_CTRL_PROBE;
	} else {
		tx->u.tx.last_frag_rate = tx->u.tx.rate;
		tx->u.tx.control->rate = tx->u.tx.rate;
	}
	tx->u.tx.control->tx_rate = tx->u.tx.rate->val;

	return TXRX_CONTINUE;
}

static ieee80211_txrx_result
ieee80211_tx_h_misc(struct ieee80211_txrx_data *tx)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
631
	u16 fc = le16_to_cpu(hdr->frame_control);
632
633
634
635
	u16 dur;
	struct ieee80211_tx_control *control = tx->u.tx.control;
	struct ieee80211_hw_mode *mode = tx->u.tx.mode;

636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
	if (!control->retry_limit) {
		if (!is_multicast_ether_addr(hdr->addr1)) {
			if (tx->skb->len + FCS_LEN > tx->local->rts_threshold
			    && tx->local->rts_threshold <
					IEEE80211_MAX_RTS_THRESHOLD) {
				control->flags |=
					IEEE80211_TXCTL_USE_RTS_CTS;
				control->flags |=
					IEEE80211_TXCTL_LONG_RETRY_LIMIT;
				control->retry_limit =
					tx->local->long_retry_limit;
			} else {
				control->retry_limit =
					tx->local->short_retry_limit;
			}
651
		} else {
652
			control->retry_limit = 1;
653
654
655
		}
	}

656
	if (tx->flags & IEEE80211_TXRXD_FRAGMENTED) {
657
658
659
660
661
662
663
664
665
666
667
668
		/* Do not use multiple retry rates when sending fragmented
		 * frames.
		 * TODO: The last fragment could still use multiple retry
		 * rates. */
		control->alt_retry_rate = -1;
	}

	/* Use CTS protection for unicast frames sent using extended rates if
	 * there are associated non-ERP stations and RTS/CTS is not configured
	 * for the frame. */
	if (mode->mode == MODE_IEEE80211G &&
	    (tx->u.tx.rate->flags & IEEE80211_RATE_ERP) &&
669
	    (tx->flags & IEEE80211_TXRXD_TXUNICAST) &&
670
	    (tx->sdata->flags & IEEE80211_SDATA_USE_PROTECTION) &&
671
672
673
	    !(control->flags & IEEE80211_TXCTL_USE_RTS_CTS))
		control->flags |= IEEE80211_TXCTL_USE_CTS_PROTECT;

674
675
676
677
678
	/* Transmit data frames using short preambles if the driver supports
	 * short preambles at the selected rate and short preambles are
	 * available on the network at the current point in time. */
	if (((fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) &&
	    (tx->u.tx.rate->flags & IEEE80211_RATE_PREAMBLE2) &&
679
	    (tx->sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE) &&
680
681
682
683
	    (!tx->sta || (tx->sta->flags & WLAN_STA_SHORT_PREAMBLE))) {
		tx->u.tx.control->tx_rate = tx->u.tx.rate->val2;
	}

684
685
686
687
	/* Setup duration field for the first fragment of the frame. Duration
	 * for remaining fragments will be updated when they are being sent
	 * to low-level driver in ieee80211_tx(). */
	dur = ieee80211_duration(tx, is_multicast_ether_addr(hdr->addr1),
688
689
				 (tx->flags & IEEE80211_TXRXD_FRAGMENTED) ?
				 tx->u.tx.extra_frag[0]->len : 0);
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
	hdr->duration_id = cpu_to_le16(dur);

	if ((control->flags & IEEE80211_TXCTL_USE_RTS_CTS) ||
	    (control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)) {
		struct ieee80211_rate *rate;

		/* Do not use multiple retry rates when using RTS/CTS */
		control->alt_retry_rate = -1;

		/* Use min(data rate, max base rate) as CTS/RTS rate */
		rate = tx->u.tx.rate;
		while (rate > mode->rates &&
		       !(rate->flags & IEEE80211_RATE_BASIC))
			rate--;

		control->rts_cts_rate = rate->val;
		control->rts_rate = rate;
	}

	if (tx->sta) {
		tx->sta->tx_packets++;
		tx->sta->tx_fragments++;
		tx->sta->tx_bytes += tx->skb->len;
		if (tx->u.tx.extra_frag) {
			int i;
			tx->sta->tx_fragments += tx->u.tx.num_extra_frag;
			for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
				tx->sta->tx_bytes +=
					tx->u.tx.extra_frag[i]->len;
			}
		}
	}

	return TXRX_CONTINUE;
}

static ieee80211_txrx_result
ieee80211_tx_h_load_stats(struct ieee80211_txrx_data *tx)
{
	struct ieee80211_local *local = tx->local;
	struct ieee80211_hw_mode *mode = tx->u.tx.mode;
	struct sk_buff *skb = tx->skb;
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
	u32 load = 0, hdrtime;

	/* TODO: this could be part of tx_status handling, so that the number
	 * of retries would be known; TX rate should in that case be stored
	 * somewhere with the packet */

	/* 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 (mode->mode == MODE_IEEE80211A ||
	    (mode->mode == MODE_IEEE80211G &&
	     tx->u.tx.rate->flags & IEEE80211_RATE_ERP))
		hdrtime = CHAN_UTIL_HDR_SHORT;
	else
		hdrtime = CHAN_UTIL_HDR_LONG;

	load = hdrtime;
	if (!is_multicast_ether_addr(hdr->addr1))
		load += hdrtime;

	if (tx->u.tx.control->flags & IEEE80211_TXCTL_USE_RTS_CTS)
		load += 2 * hdrtime;
	else if (tx->u.tx.control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)
		load += hdrtime;

	load += skb->len * tx->u.tx.rate->rate_inv;

	if (tx->u.tx.extra_frag) {
		int i;
		for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
			load += 2 * hdrtime;
			load += tx->u.tx.extra_frag[i]->len *
				tx->u.tx.rate->rate;
		}
	}

	/* Divide channel_use by 8 to avoid wrapping around the counter */
	load >>= CHAN_UTIL_SHIFT;
	local->channel_use_raw += load;
	if (tx->sta)
		tx->sta->channel_use_raw += load;
	tx->sdata->channel_use_raw += load;

	return TXRX_CONTINUE;
}

/* TODO: implement register/unregister functions for adding TX/RX handlers
 * into ordered list */

ieee80211_tx_handler ieee80211_tx_handlers[] =
{
	ieee80211_tx_h_check_assoc,
	ieee80211_tx_h_sequence,
	ieee80211_tx_h_ps_buf,
	ieee80211_tx_h_select_key,
	ieee80211_tx_h_michael_mic_add,
	ieee80211_tx_h_fragment,
792
	ieee80211_tx_h_encrypt,
793
794
795
796
797
798
799
800
801
802
803
804
805
	ieee80211_tx_h_rate_ctrl,
	ieee80211_tx_h_misc,
	ieee80211_tx_h_load_stats,
	NULL
};

/* actual transmit path */

/*
 * deal with packet injection down monitor interface
 * with Radiotap Header -- only called for monitor mode interface
 */
static ieee80211_txrx_result
806
807
__ieee80211_parse_tx_radiotap(struct ieee80211_txrx_data *tx,
			      struct sk_buff *skb)
808
809
810
811
812
813
814
815
816
817
818
819
820
821
{
	/*
	 * this is the moment to interpret and discard the radiotap header that
	 * must be at the start of the packet injected in Monitor mode
	 *
	 * Need to take some care with endian-ness since radiotap
	 * args are little-endian
	 */

	struct ieee80211_radiotap_iterator iterator;
	struct ieee80211_radiotap_header *rthdr =
		(struct ieee80211_radiotap_header *) skb->data;
	struct ieee80211_hw_mode *mode = tx->local->hw.conf.mode;
	int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len);
822
	struct ieee80211_tx_control *control = tx->u.tx.control;
823

824
825
826
	control->flags |= IEEE80211_TXCTL_DO_NOT_ENCRYPT;
	tx->flags |= IEEE80211_TXRXD_TX_INJECTED;
	tx->flags &= ~IEEE80211_TXRXD_FRAGMENTED;
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858

	/*
	 * for every radiotap entry that is present
	 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
	 * entries present, or -EINVAL on error)
	 */

	while (!ret) {
		int i, target_rate;

		ret = ieee80211_radiotap_iterator_next(&iterator);

		if (ret)
			continue;

		/* see if this argument is something we can use */
		switch (iterator.this_arg_index) {
		/*
		 * You must take care when dereferencing iterator.this_arg
		 * for multibyte types... the pointer is not aligned.  Use
		 * get_unaligned((type *)iterator.this_arg) to dereference
		 * iterator.this_arg for type "type" safely on all arches.
		*/
		case IEEE80211_RADIOTAP_RATE:
			/*
			 * radiotap rate u8 is in 500kbps units eg, 0x02=1Mbps
			 * ieee80211 rate int is in 100kbps units eg, 0x0a=1Mbps
			 */
			target_rate = (*iterator.this_arg) * 5;
			for (i = 0; i < mode->num_rates; i++) {
				struct ieee80211_rate *r = &mode->rates[i];

859
860
861
862
				if (r->rate == target_rate) {
					tx->u.tx.rate = r;
					break;
				}
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
			}
			break;

		case IEEE80211_RADIOTAP_ANTENNA:
			/*
			 * radiotap uses 0 for 1st ant, mac80211 is 1 for
			 * 1st ant
			 */
			control->antenna_sel_tx = (*iterator.this_arg) + 1;
			break;

		case IEEE80211_RADIOTAP_DBM_TX_POWER:
			control->power_level = *iterator.this_arg;
			break;

		case IEEE80211_RADIOTAP_FLAGS:
			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
				/*
				 * this indicates that the skb we have been
				 * handed has the 32-bit FCS CRC at the end...
				 * we should react to that by snipping it off
				 * because it will be recomputed and added
				 * on transmission
				 */
				if (skb->len < (iterator.max_length + FCS_LEN))
					return TXRX_DROP;

				skb_trim(skb, skb->len - FCS_LEN);
			}
892
893
894
895
896
			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
				control->flags &=
					~IEEE80211_TXCTL_DO_NOT_ENCRYPT;
			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
				tx->flags |= IEEE80211_TXRXD_FRAGMENTED;
897
898
			break;

899
900
901
902
903
904
		/*
		 * Please update the file
		 * Documentation/networking/mac80211-injection.txt
		 * when parsing new fields here.
		 */

905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
		default:
			break;
		}
	}

	if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
		return TXRX_DROP;

	/*
	 * remove the radiotap header
	 * iterator->max_length was sanity-checked against
	 * skb->len by iterator init
	 */
	skb_pull(skb, iterator.max_length);

	return TXRX_CONTINUE;
}

923
924
925
926
/*
 * initialises @tx
 */
static ieee80211_txrx_result
927
928
929
930
931
932
__ieee80211_tx_prepare(struct ieee80211_txrx_data *tx,
		       struct sk_buff *skb,
		       struct net_device *dev,
		       struct ieee80211_tx_control *control)
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
933
	struct ieee80211_hdr *hdr;
934
935
936
937
938
939
940
941
942
943
	struct ieee80211_sub_if_data *sdata;
	ieee80211_txrx_result res = TXRX_CONTINUE;

	int hdrlen;

	memset(tx, 0, sizeof(*tx));
	tx->skb = skb;
	tx->dev = dev; /* use original interface */
	tx->local = local;
	tx->sdata = IEEE80211_DEV_TO_SUB_IF(dev);
944
	tx->u.tx.control = control;
945
	/*
946
947
	 * Set this flag (used below to indicate "automatic fragmentation"),
	 * it will be cleared/left by radiotap as desired.
948
	 */
949
	tx->flags |= IEEE80211_TXRXD_FRAGMENTED;
950
951
952
953

	/* process and remove the injection radiotap header */
	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	if (unlikely(sdata->type == IEEE80211_IF_TYPE_MNTR)) {
954
		if (__ieee80211_parse_tx_radiotap(tx, skb) == TXRX_DROP)
955
			return TXRX_DROP;
956

957
		/*
958
959
960
		 * __ieee80211_parse_tx_radiotap has now removed
		 * the radiotap header that was present and pre-filled
		 * 'tx' with tx control information.
961
962
963
		 */
	}

964
965
	hdr = (struct ieee80211_hdr *) skb->data;

966
967
	tx->sta = sta_info_get(local, hdr->addr1);
	tx->fc = le16_to_cpu(hdr->frame_control);
968

969
970
	if (is_multicast_ether_addr(hdr->addr1)) {
		tx->flags &= ~IEEE80211_TXRXD_TXUNICAST;
971
		control->flags |= IEEE80211_TXCTL_NO_ACK;
972
973
	} else {
		tx->flags |= IEEE80211_TXRXD_TXUNICAST;
974
		control->flags &= ~IEEE80211_TXCTL_NO_ACK;
975
	}
976
977
978
979
980
981
982
983
984
985

	if (tx->flags & IEEE80211_TXRXD_FRAGMENTED) {
		if ((tx->flags & IEEE80211_TXRXD_TXUNICAST) &&
		    skb->len + FCS_LEN > local->fragmentation_threshold &&
		    !local->ops->set_frag_threshold)
			tx->flags |= IEEE80211_TXRXD_FRAGMENTED;
		else
			tx->flags &= ~IEEE80211_TXRXD_FRAGMENTED;
	}

986
987
988
989
990
991
	if (!tx->sta)
		control->flags |= IEEE80211_TXCTL_CLEAR_DST_MASK;
	else if (tx->sta->clear_dst_mask) {
		control->flags |= IEEE80211_TXCTL_CLEAR_DST_MASK;
		tx->sta->clear_dst_mask = 0;
	}
992

993
994
995
996
997
998
999
1000
1001
1002
1003
	hdrlen = ieee80211_get_hdrlen(tx->fc);
	if (skb->len > hdrlen + sizeof(rfc1042_header) + 2) {
		u8 *pos = &skb->data[hdrlen + sizeof(rfc1042_header)];
		tx->ethertype = (pos[0] << 8) | pos[1];
	}
	control->flags |= IEEE80211_TXCTL_FIRST_FRAGMENT;

	return res;
}

/* Device in tx->dev has a reference added; use dev_put(tx->dev) when
1004
1005
1006
1007
1008
1009
1010
1011
 * finished with it.
 *
 * NB: @tx is uninitialised when passed in here
 */
static int ieee80211_tx_prepare(struct ieee80211_txrx_data *tx,
				struct sk_buff *skb,
				struct net_device *mdev,
				struct ieee80211_tx_control *control)
1012
1013
1014
1015
1016
{
	struct ieee80211_tx_packet_data *pkt_data;
	struct net_device *dev;

	pkt_data = (struct ieee80211_tx_packet_data *)skb->cb;
1017
	dev = dev_get_by_index(&init_net, pkt_data->ifindex);
1018
1019
1020
1021
1022
1023
	if (unlikely(dev && !is_ieee80211_device(dev, mdev))) {
		dev_put(dev);
		dev = NULL;
	}
	if (unlikely(!dev))
		return -ENODEV;
1024
	/* initialises tx with control */
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
	__ieee80211_tx_prepare(tx, skb, dev, control);
	return 0;
}

static int __ieee80211_tx(struct ieee80211_local *local, struct sk_buff *skb,
			  struct ieee80211_txrx_data *tx)
{
	struct ieee80211_tx_control *control = tx->u.tx.control;
	int ret, i;

	if (!ieee80211_qdisc_installed(local->mdev) &&
	    __ieee80211_queue_stopped(local, 0)) {
		netif_stop_queue(local->mdev);
		return IEEE80211_TX_AGAIN;
	}
	if (skb) {
1041
1042
		ieee80211_dump_frame(wiphy_name(local->hw.wiphy),
				     "TX to low-level driver", skb);
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
		ret = local->ops->tx(local_to_hw(local), skb, control);
		if (ret)
			return IEEE80211_TX_AGAIN;
		local->mdev->trans_start = jiffies;
		ieee80211_led_tx(local, 1);
	}
	if (tx->u.tx.extra_frag) {
		control->flags &= ~(IEEE80211_TXCTL_USE_RTS_CTS |
				    IEEE80211_TXCTL_USE_CTS_PROTECT |
				    IEEE80211_TXCTL_CLEAR_DST_MASK |
				    IEEE80211_TXCTL_FIRST_FRAGMENT);
		for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
			if (!tx->u.tx.extra_frag[i])
				continue;
			if (__ieee80211_queue_stopped(local, control->queue))
				return IEEE80211_TX_FRAG_AGAIN;
			if (i == tx->u.tx.num_extra_frag) {
				control->tx_rate = tx->u.tx.last_frag_hwrate;
				control->rate = tx->u.tx.last_frag_rate;
1062
				if (tx->flags & IEEE80211_TXRXD_TXPROBE_LAST_FRAG)
1063
1064
1065
1066
1067
1068
1069
					control->flags |=
						IEEE80211_TXCTL_RATE_CTRL_PROBE;
				else
					control->flags &=
						~IEEE80211_TXCTL_RATE_CTRL_PROBE;
			}

1070
			ieee80211_dump_frame(wiphy_name(local->hw.wiphy),
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
					     "TX to low-level driver",
					     tx->u.tx.extra_frag[i]);
			ret = local->ops->tx(local_to_hw(local),
					    tx->u.tx.extra_frag[i],
					    control);
			if (ret)
				return IEEE80211_TX_FRAG_AGAIN;
			local->mdev->trans_start = jiffies;
			ieee80211_led_tx(local, 1);
			tx->u.tx.extra_frag[i] = NULL;
		}
		kfree(tx->u.tx.extra_frag);
		tx->u.tx.extra_frag = NULL;
	}
	return IEEE80211_TX_OK;
}

static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb,
1089
			struct ieee80211_tx_control *control)
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	struct sta_info *sta;
	ieee80211_tx_handler *handler;
	struct ieee80211_txrx_data tx;
	ieee80211_txrx_result res = TXRX_DROP, res_prepare;
	int ret, i;

	WARN_ON(__ieee80211_queue_pending(local, control->queue));

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

1105
	/* initialises tx */
1106
1107
1108
1109
1110
1111
1112
	res_prepare = __ieee80211_tx_prepare(&tx, skb, dev, control);

	if (res_prepare == TXRX_DROP) {
		dev_kfree_skb(skb);
		return 0;
	}

1113
1114
1115
1116
1117
1118
	/*
	 * key references are protected using RCU and this requires that
	 * we are in a read-site RCU section during receive processing
	 */
	rcu_read_lock();

1119
1120
1121
	sta = tx.sta;
	tx.u.tx.mode = local->hw.conf.mode;

1122
1123
1124
1125
1126
	for (handler = local->tx_handlers; *handler != NULL;
	     handler++) {
		res = (*handler)(&tx);
		if (res != TXRX_CONTINUE)
			break;
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
	}

	skb = tx.skb; /* handlers are allowed to change skb */

	if (sta)
		sta_info_put(sta);

	if (unlikely(res == TXRX_DROP)) {
		I802_DEBUG_INC(local->tx_handlers_drop);
		goto drop;
	}

	if (unlikely(res == TXRX_QUEUED)) {
		I802_DEBUG_INC(local->tx_handlers_queued);
1141
		rcu_read_unlock();
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
		return 0;
	}

	if (tx.u.tx.extra_frag) {
		for (i = 0; i < tx.u.tx.num_extra_frag; i++) {
			int next_len, dur;
			struct ieee80211_hdr *hdr =
				(struct ieee80211_hdr *)
				tx.u.tx.extra_frag[i]->data;

			if (i + 1 < tx.u.tx.num_extra_frag) {
				next_len = tx.u.tx.extra_frag[i + 1]->len;
			} else {
				next_len = 0;
				tx.u.tx.rate = tx.u.tx.last_frag_rate;
				tx.u.tx.last_frag_hwrate = tx.u.tx.rate->val;
			}
			dur = ieee80211_duration(&tx, 0, next_len);
			hdr->duration_id = cpu_to_le16(dur);
		}
	}

retry:
	ret = __ieee80211_tx(local, skb, &tx);
	if (ret) {
		struct ieee80211_tx_stored_packet *store =
			&local->pending_packet[control->queue];

		if (ret == IEEE80211_TX_FRAG_AGAIN)
			skb = NULL;
		set_bit(IEEE80211_LINK_STATE_PENDING,
			&local->state[control->queue]);
		smp_mb();
		/* When the driver gets out of buffers during sending of
		 * fragments and calls ieee80211_stop_queue, there is
		 * a small window between IEEE80211_LINK_STATE_XOFF and
		 * IEEE80211_LINK_STATE_PENDING flags are set. If a buffer
		 * gets available in that window (i.e. driver calls
		 * ieee80211_wake_queue), we would end up with ieee80211_tx
		 * called with IEEE80211_LINK_STATE_PENDING. Prevent this by
		 * continuing transmitting here when that situation is
		 * possible to have happened. */
		if (!__ieee80211_queue_stopped(local, control->queue)) {
			clear_bit(IEEE80211_LINK_STATE_PENDING,
				  &local->state[control->queue]);
			goto retry;
		}
		memcpy(&store->control, control,
		       sizeof(struct ieee80211_tx_control));
		store->skb = skb;
		store->extra_frag = tx.u.tx.extra_frag;
		store->num_extra_frag = tx.u.tx.num_extra_frag;
		store->last_frag_hwrate = tx.u.tx.last_frag_hwrate;
		store->last_frag_rate = tx.u.tx.last_frag_rate;
1196
1197
		store->last_frag_rate_ctrl_probe =
			!!(tx.flags & IEEE80211_TXRXD_TXPROBE_LAST_FRAG);
1198
	}
1199
	rcu_read_unlock();
1200
1201
1202
1203
1204
1205
1206
1207
1208
	return 0;

 drop:
	if (skb)
		dev_kfree_skb(skb);
	for (i = 0; i < tx.u.tx.num_extra_frag; i++)
		if (tx.u.tx.extra_frag[i])
			dev_kfree_skb(tx.u.tx.extra_frag[i]);
	kfree(tx.u.tx.extra_frag);
1209
	rcu_read_unlock();
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
	return 0;
}

/* device xmit handlers */

int ieee80211_master_start_xmit(struct sk_buff *skb,
				struct net_device *dev)
{
	struct ieee80211_tx_control control;
	struct ieee80211_tx_packet_data *pkt_data;
	struct net_device *odev = NULL;
	struct ieee80211_sub_if_data *osdata;
	int headroom;
	int ret;

	/*
	 * copy control out of the skb so other people can use skb->cb
	 */
	pkt_data = (struct ieee80211_tx_packet_data *)skb->cb;
	memset(&control, 0, sizeof(struct ieee80211_tx_control));

	if (pkt_data->ifindex)
1232
		odev = dev_get_by_index(&init_net, pkt_data->ifindex);
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
	if (unlikely(odev && !is_ieee80211_device(odev, dev))) {
		dev_put(odev);
		odev = NULL;
	}
	if (unlikely(!odev)) {
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
		printk(KERN_DEBUG "%s: Discarded packet with nonexistent "
		       "originating device\n", dev->name);
#endif
		dev_kfree_skb(skb);
		return 0;
	}
	osdata = IEEE80211_DEV_TO_SUB_IF(odev);

	headroom = osdata->local->tx_headroom + IEEE80211_ENCRYPT_HEADROOM;
	if (skb_headroom(skb) < headroom) {
		if (pskb_expand_head(skb, headroom, 0, GFP_ATOMIC)) {
			dev_kfree_skb(skb);
			dev_put(odev);
			return 0;
		}
	}

	control.ifindex = odev->ifindex;
	control.type = osdata->type;
1258
	if (pkt_data->flags & IEEE80211_TXPD_REQ_TX_STATUS)
1259
		control.flags |= IEEE80211_TXCTL_REQ_TX_STATUS;
1260
	if (pkt_data->flags & IEEE80211_TXPD_DO_NOT_ENCRYPT)
1261
		control.flags |= IEEE80211_TXCTL_DO_NOT_ENCRYPT;
1262
	if (pkt_data->flags & IEEE80211_TXPD_REQUEUE)
1263
		control.flags |= IEEE80211_TXCTL_REQUEUE;
1264
1265
	if (pkt_data->flags & IEEE80211_TXPD_EAPOL_FRAME)
		control.flags |= IEEE80211_TXCTL_EAPOL_FRAME;
1266
1267
	control.queue = pkt_data->queue;

1268
	ret = ieee80211_tx(odev, skb, &control);
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
	dev_put(odev);

	return ret;
}

int ieee80211_monitor_start_xmit(struct sk_buff *skb,
				 struct net_device *dev)
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	struct ieee80211_tx_packet_data *pkt_data;
	struct ieee80211_radiotap_header *prthdr =
		(struct ieee80211_radiotap_header *)skb->data;
1281
	u16 len_rthdr;
1282

1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
	/* check for not even having the fixed radiotap header part */
	if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
		goto fail; /* too short to be possibly valid */

	/* is it a header version we can trust to find length from? */
	if (unlikely(prthdr->it_version))
		goto fail; /* only version 0 is supported */

	/* then there must be a radiotap header with a length we can use */
	len_rthdr = ieee80211_get_radiotap_len(skb->data);

	/* does the skb contain enough to deliver on the alleged length? */
	if (unlikely(skb->len < len_rthdr))
		goto fail; /* skb too short for claimed rt header extent */
1297
1298
1299
1300
1301

	skb->dev = local->mdev;

	pkt_data = (struct ieee80211_tx_packet_data *)skb->cb;
	memset(pkt_data, 0, sizeof(*pkt_data));
1302
	/* needed because we set skb device to master */
1303
	pkt_data->ifindex = dev->ifindex;
1304

1305
	pkt_data->flags |= IEEE80211_TXPD_DO_NOT_ENCRYPT;
1306
1307
1308
1309
1310
1311
1312

	/*
	 * fix up the pointers accounting for the radiotap
	 * header still being in there.  We are being given
	 * a precooked IEEE80211 header so no need for
	 * normal processing
	 */
1313
	skb_set_mac_header(skb, len_rthdr);
1314
	/*
1315
1316
	 * these are just fixed to the end of the rt area since we
	 * don't have any better information and at this point, nobody cares
1317
	 */
1318
1319
	skb_set_network_header(skb, len_rthdr);
	skb_set_transport_header(skb, len_rthdr);
1320

1321
1322
	/* pass the radiotap header up to the next stage intact */
	dev_queue_xmit(skb);
1323
	return NETDEV_TX_OK;
1324
1325
1326
1327

fail:
	dev_kfree_skb(skb);
	return NETDEV_TX_OK; /* meaning, we dealt with the skb */
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
}

/**
 * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type
 * subinterfaces (wlan#, WDS, and VLAN interfaces)
 * @skb: packet to be sent
 * @dev: incoming interface
 *
 * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will
 * not be freed, and caller is responsible for either retrying later or freeing
 * skb).
 *
 * This function takes in an Ethernet header and encapsulates it with suitable
 * IEEE 802.11 header based on which interface the packet is coming in. The
 * encapsulated packet will then be passed to master interface, wlan#.11, for
 * transmission (through low-level driver).
 */
int ieee80211_subif_start_xmit(struct sk_buff *skb,
			       struct net_device *dev)
{
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	struct ieee80211_tx_packet_data *pkt_data;
	struct ieee80211_sub_if_data *sdata;
	int ret = 1, head_need;
	u16 ethertype, hdrlen, fc;
	struct ieee80211_hdr hdr;
	const u8 *encaps_data;
	int encaps_len, skip_header_bytes;
1356
	int nh_pos, h_pos;
1357
	struct sta_info *sta;
1358
	u32 sta_flags = 0;
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375

	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	if (unlikely(skb->len < ETH_HLEN)) {
		printk(KERN_DEBUG "%s: short skb (len=%d)\n",
		       dev->name, skb->len);
		ret = 0;
		goto fail;
	}

	nh_pos = skb_network_header(skb) - skb->data;
	h_pos = skb_transport_header(skb) - skb->data;

	/* convert Ethernet header to proper 802.11 header (based on
	 * operation mode) */
	ethertype = (skb->data[12] << 8) | skb->data[13];
	fc = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA;

1376
1377
1378
	switch (sdata->type) {
	case IEEE80211_IF_TYPE_AP:
	case IEEE80211_IF_TYPE_VLAN:
1379
1380
1381
1382
1383
1384
		fc |= IEEE80211_FCTL_FROMDS;
		/* DA BSSID SA */
		memcpy(hdr.addr1, skb->data, ETH_ALEN);
		memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
		memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
		hdrlen = 24;
1385
1386
		break;
	case IEEE80211_IF_TYPE_WDS:
1387
1388
1389
1390
1391
1392
1393
		fc |= IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS;
		/* RA TA DA SA */
		memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
		memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
		memcpy(hdr.addr3, skb->data, ETH_ALEN);
		memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
		hdrlen = 30;
1394
1395
		break;
	case IEEE80211_IF_TYPE_STA:
1396
1397
1398
1399
1400
1401
		fc |= IEEE80211_FCTL_TODS;
		/* BSSID SA DA */
		memcpy(hdr.addr1, sdata->u.sta.bssid, ETH_ALEN);
		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
		memcpy(hdr.addr3, skb->data, ETH_ALEN);
		hdrlen = 24;
1402
1403
		break;
	case IEEE80211_IF_TYPE_IBSS:
1404
1405
1406
1407
1408
		/* DA SA BSSID */
		memcpy(hdr.addr1, skb->data, ETH_ALEN);
		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
		memcpy(hdr.addr3, sdata->u.sta.bssid, ETH_ALEN);
		hdrlen = 24;
1409
1410
		break;
	default:
1411
1412
1413
1414
1415
1416
		ret = 0;
		goto fail;
	}

	sta = sta_info_get(local, hdr.addr1);
	if (sta) {
1417
		sta_flags = sta->flags;
1418
1419
1420
		sta_info_put(sta);
	}

1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
	/* receiver is QoS enabled, use a QoS type frame */
	if (sta_flags & WLAN_STA_WME) {
		fc |= IEEE80211_STYPE_QOS_DATA;
		hdrlen += 2;
	}

	/*
	 * If port access control is enabled, drop frames to unauthorised
	 * stations unless they are EAPOL frames from the local station.
	 */
	if (unlikely(sdata->ieee802_1x_pac &&
		     !(sta_flags & WLAN_STA_AUTHORIZED) &&
		     !(ethertype == ETH_P_PAE &&
		       compare_ether_addr(dev->dev_addr,
					  skb->data + ETH_ALEN) == 0))) {
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
		DECLARE_MAC_BUF(mac);

		if (net_ratelimit())
			printk(KERN_DEBUG "%s: dropped frame to %s"
			       " (unauthorized port)\n", dev->name,
			       print_mac(mac, hdr.addr1));
#endif

		I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);

		ret = 0;
		goto fail;
	}

1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
	hdr.frame_control = cpu_to_le16(fc);
	hdr.duration_id = 0;
	hdr.seq_ctrl = 0;

	skip_header_bytes = ETH_HLEN;
	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
		encaps_data = bridge_tunnel_header;
		encaps_len = sizeof(bridge_tunnel_header);
		skip_header_bytes -= 2;
	} else if (ethertype >= 0x600) {
		encaps_data = rfc1042_header;
		encaps_len = sizeof(rfc1042_header);
		skip_header_bytes -= 2;
	} else {
		encaps_data = NULL;
		encaps_len = 0;
	}

	skb_pull(skb, skip_header_bytes);
	nh_pos -= skip_header_bytes;
	h_pos -= skip_header_bytes;

	/* TODO: implement support for fragments so that there is no need to
	 * reallocate and copy payload; it might be enough to support one
	 * extra fragment that would be copied in the beginning of the frame
	 * data.. anyway, it would be nice to include this into skb structure
	 * somehow
	 *
	 * There are few options for this:
	 * use skb->cb as an extra space for 802.11 header
	 * allocate new buffer if not enough headroom
	 * make sure that there is enough headroom in every skb by increasing
	 * build in headroom in __dev_alloc_skb() (linux/skbuff.h) and
	 * alloc_skb() (net/core/skbuff.c)
	 */
	head_need = hdrlen + encaps_len + local->tx_headroom;
	head_need -= skb_headroom(skb);

	/* We are going to modify skb data, so make a copy of it if happens to
	 * be cloned. This could happen, e.g., with Linux bridge code passing
	 * us broadcast frames. */

	if (head_need > 0 || skb_cloned(skb)) {
#if 0
		printk(KERN_DEBUG "%s: need to reallocate buffer for %d bytes "
		       "of headroom\n", dev->name, head_need);
#endif

		if (skb_cloned(skb))
			I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
		else
			I802_DEBUG_INC(local->tx_expand_skb_head);
		/* Since we have to reallocate the buffer, make sure that there
		 * is enough room for possible WEP IV/ICV and TKIP (8 bytes
		 * before payload and 12 after). */
		if (pskb_expand_head(skb, (head_need > 0 ? head_need + 8 : 8),
				     12, GFP_ATOMIC)) {
			printk(KERN_DEBUG "%s: failed to reallocate TX buffer"
			       "\n", dev->name);
			goto fail;
		}
	}

	if (encaps_data) {
		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
		nh_pos += encaps_len;
		h_pos += encaps_len;
	}
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532

	if (fc & IEEE80211_STYPE_QOS_DATA) {
		__le16 *qos_control;

		qos_control = (__le16*) skb_push(skb, 2);
		memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
		/*
		 * Maybe we could actually set some fields here, for now just
		 * initialise to zero to indicate no special operation.
		 */
		*qos_control = 0;
	} else
		memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);

1533
1534
1535
1536
1537
1538
	nh_pos += hdrlen;
	h_pos += hdrlen;

	pkt_data = (struct ieee80211_tx_packet_data *)skb->cb;
	memset(pkt_data, 0, sizeof(struct ieee80211_tx_packet_data));
	pkt_data->ifindex = dev->ifindex;
1539
1540
	if (ethertype == ETH_P_PAE)
		pkt_data->flags |= IEEE80211_TXPD_EAPOL_FRAME;
1541
1542

	skb->dev = local->mdev;
1543
1544
	dev->stats.tx_packets++;
	dev->stats.tx_bytes += skb->len;
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	/* Update skb pointers to various headers since this modified frame
	 * is going to go through Linux networking code that may potentially
	 * need things like pointer to IP header. */
	skb_set_mac_header(skb, 0);
	skb_set_network_header(skb, nh_pos);
	skb_set_transport_header(skb, h_pos);

	dev->trans_start = jiffies;
	dev_queue_xmit(skb);

	return 0;

 fail:
	if (!ret)
		dev_kfree_skb(skb);

	return ret;
}

/* helper functions for pending packets for when queues are stopped */

void ieee80211_clear_tx_pending(struct ieee80211_local *local)
{
	int i, j;
	struct ieee80211_tx_stored_packet *store;

	for (i = 0; i < local->hw.queues; i++) {
		if (!__ieee80211_queue_pending(local, i))
			continue;
		store = &local->pending_packet[i];
		kfree_skb(store->skb);
		for (j = 0; j < store->num_extra_frag; j++)
			kfree_skb(store->extra_frag[j]);
		kfree(store->extra_frag);
		clear_bit(IEEE80211_LINK_STATE_PENDING, &local->state[i]);
	}
}

void ieee80211_tx_pending(unsigned long data)
{
	struct ieee80211_local *local = (struct ieee80211_local *)data;
	struct net_device *dev = local->mdev;
	struct ieee80211_tx_stored_packet *store;
	struct ieee80211_txrx_data tx;
	int i, ret, reschedule = 0;

	netif_tx_lock_bh(dev);
	for (i = 0; i < local->hw.queues; i++) {
		if (__ieee80211_queue_stopped(local, i))
			continue;
		if (!__ieee80211_queue_pending(local, i)) {
			reschedule = 1;
			continue;
		}
		store = &local->pending_packet[i];
		tx.u.tx.control = &store->control;
		tx.u.tx.extra_frag = store->extra_frag;
		tx.u.tx.num_extra_frag = store->num_extra_frag;
		tx.u.tx.last_frag_hwrate = store->last_frag_hwrate;
		tx.u.tx.last_frag_rate = store->last_frag_rate;
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		tx.flags = 0;
		if (store->last_frag_rate_ctrl_probe)
			tx.flags |= IEEE80211_TXRXD_TXPROBE_LAST_FRAG;
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		ret = __ieee80211_tx(local, store->skb, &tx);
		if (ret) {
			if (ret == IEEE80211_TX_FRAG_AGAIN)
				store->skb = NULL;
		} else {
			clear_bit(IEEE80211_LINK_STATE_PENDING,
				  &local->state[i]);
			reschedule = 1;
		}
	}
	netif_tx_unlock_bh(dev);
	if (reschedule) {
		if (!ieee80211_qdisc_installed(dev)) {
			if (!__ieee80211_queue_stopped(local, 0))
				netif_wake_queue(dev);
		} else
			netif_schedule(dev);
	}
}

/* functions for drivers to get certain frames */

static void ieee80211_beacon_add_tim(struct ieee80211_local *local,
				     struct ieee80211_if_ap *bss,
				     struct sk_buff *skb)
{
	u8 *pos, *tim;
	int aid0 = 0;
	int i, have_bits = 0, n1, n2;

	/* Generate bitmap for TIM only if there are any STAs in power save
	 * mode. */
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	read_lock_bh(&local->sta_lock);
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	if (atomic_read(&bss->num_sta_ps) > 0)
		/* in the hope that this is faster than
		 * checking byte-for-byte */
		have_bits = !bitmap_empty((unsigned long*)bss->tim,
					  IEEE80211_MAX_AID+1);

	if (bss->dtim_count == 0)
		bss->dtim_count = bss->dtim_period - 1;
	else
		bss->dtim_count--;

	tim = pos = (u8 *) skb_put(skb, 6);
	*pos++ = WLAN_EID_TIM;
	*pos++ = 4;
	*pos++ = bss->dtim_count;
	*pos++ = bss->dtim_period;

	if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf))
		aid0 = 1;

	if (have_bits) {
		/* Find largest even number N1 so that bits numbered 1 through
		 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
		 * (N2 + 1) x 8 through 2007 are 0. */
		n1 = 0;
		for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
			if (bss->tim[i]) {
				n1 = i & 0xfe;
				break;
			}
		}
		n2 = n1;
		for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
			if (bss->tim[i]) {
				n2 = i;
				break;
			}
		}

		/* Bitmap control */
		*pos++ = n1 | aid0;
		/* Part Virt Bitmap */
		memcpy(pos, bss->tim + n1, n2 - n1 + 1);

		tim[1] = n2 - n1 + 4;
		skb_put(skb, n2 - n1);
	} else {
		*pos++ = aid0; /* Bitmap control */
		*pos++ = 0; /* Part Virt Bitmap */
	}
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	read_unlock_bh(&local->sta_lock);
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}

struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw, int if_id,
				     struct ieee80211_tx_control *control)
{
	struct ieee80211_local *local = hw_to_local(hw);
	struct sk_buff *skb;
	struct net_device *bdev;
	struct ieee80211_sub_if_data *sdata = NULL;
	struct ieee80211_if_ap *ap = NULL;
1703
	struct rate_selection rsel;
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	u8 *b_head, *b_tail;
	int bh_len, bt_len;

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	bdev = dev_get_by_index(&init_net, if_id);
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	if (bdev) {
		sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
		ap = &sdata->u.ap;
		dev_put(bdev);
	}

	if (!ap || sdata->type != IEEE80211_IF_TYPE_AP ||
	    !ap->beacon_head) {
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
		if (net_ratelimit())
			printk(KERN_DEBUG "no beacon data avail for idx=%d "
			       "(%s)\n", if_id, bdev ? bdev->name : "N/A");
#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
		return NULL;
	}

	/* Assume we are generating the normal beacon locally */
	b_head = ap->beacon_head;
	b_tail = ap->beacon_tail;
	bh_len = ap->beacon_head_len;
	bt_len = ap->beacon_tail_len;

	skb = dev_alloc_skb(local->tx_headroom +
		bh_len + bt_len + 256 /* maximum TIM len */);
	if (!skb)
		return NULL;

	skb_reserve(skb, local->tx_headroom);
	memcpy(skb_put(skb, bh_len), b_head, bh_len);