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authorJohannes Berg <johannes@sipsolutions.net>2007-07-27 17:43:22 +0400
committerDavid S. Miller <davem@sunset.davemloft.net>2007-10-11 03:47:33 +0400
commite2ebc74d7e3d71600640db6fbb28cc2f362184c1 (patch)
tree7f9a830869b9f6157ee8235feb4953df7a639dbd /net/mac80211/tx.c
parent340e11f332c695c43f506e82b1d39d00716c5005 (diff)
downloadlinux-e2ebc74d7e3d71600640db6fbb28cc2f362184c1.tar.xz
[MAC80211]: split TX path into own file
Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Jiri Benc <jbenc@suse.cz> Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'net/mac80211/tx.c')
-rw-r--r--net/mac80211/tx.c1869
1 files changed, 1869 insertions, 0 deletions
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
new file mode 100644
index 000000000000..dc128b412eab
--- /dev/null
+++ b/net/mac80211/tx.c
@@ -0,0 +1,1869 @@
+/*
+ * 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>
+#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;
+
+ 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)
+ printk(" A1=" MAC_FMT, MAC_ARG(hdr->addr1));
+ if (hdrlen >= 16)
+ printk(" A2=" MAC_FMT, MAC_ARG(hdr->addr2));
+ if (hdrlen >= 24)
+ printk(" A3=" MAC_FMT, MAC_ARG(hdr->addr3));
+ if (hdrlen >= 30)
+ printk(" A4=" MAC_FMT, MAC_ARG(hdr->addr4));
+ 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,
+ local->short_preamble);
+
+ 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,
+ txrate->rate, erp,
+ local->short_preamble);
+ }
+
+ 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;
+
+ if (unlikely(tx->local->sta_scanning != 0) &&
+ ((tx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
+ (tx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PROBE_REQ))
+ return TXRX_DROP;
+
+ if (tx->u.tx.ps_buffered)
+ return TXRX_CONTINUE;
+
+ sta_flags = tx->sta ? tx->sta->flags : 0;
+
+ if (likely(tx->u.tx.unicast)) {
+ 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
+ printk(KERN_DEBUG "%s: dropped data frame to not "
+ "associated station " MAC_FMT "\n",
+ tx->dev->name, MAC_ARG(hdr->addr1));
+#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->local->allow_broadcast_always &&
+ tx->sdata->type != IEEE80211_IF_TYPE_IBSS)) {
+ /*
+ * No associated STAs - no need to send multicast
+ * frames.
+ */
+ return TXRX_DROP;
+ }
+ return TXRX_CONTINUE;
+ }
+
+ if (unlikely(!tx->u.tx.mgmt_interface && tx->sdata->ieee802_1x &&
+ !(sta_flags & WLAN_STA_AUTHORIZED))) {
+#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
+ printk(KERN_DEBUG "%s: dropped frame to " MAC_FMT
+ " (unauthorized port)\n", tx->dev->name,
+ MAC_ARG(hdr->addr1));
+#endif
+ I802_DEBUG_INC(tx->local->tx_handlers_drop_unauth_port);
+ return TXRX_DROP;
+ }
+
+ 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;
+
+ read_lock(&local->sub_if_lock);
+ list_for_each_entry(sdata, &local->sub_if_list, list) {
+ 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);
+ }
+ read_unlock(&local->sub_if_lock);
+
+ spin_lock_bh(&local->sta_lock);
+ 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);
+ }
+ spin_unlock_bh(&local->sta_lock);
+
+ local->total_ps_buffered = total;
+ printk(KERN_DEBUG "%s: PS buffers full - purged %d frames\n",
+ local->mdev->name, purged);
+}
+
+static inline ieee80211_txrx_result
+ieee80211_tx_h_multicast_ps_buf(struct ieee80211_txrx_data *tx)
+{
+ /* 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 */
+ if ((tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING) &&
+ tx->sdata->type != IEEE80211_IF_TYPE_WDS &&
+ tx->sdata->bss && atomic_read(&tx->sdata->bss->num_sta_ps) &&
+ !(tx->fc & IEEE80211_FCTL_ORDER)) {
+ 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;
+ }
+
+ return TXRX_CONTINUE;
+}
+
+static inline ieee80211_txrx_result
+ieee80211_tx_h_unicast_ps_buf(struct ieee80211_txrx_data *tx)
+{
+ struct sta_info *sta = tx->sta;
+
+ 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
+ printk(KERN_DEBUG "STA " MAC_FMT " aid %d: PS buffer (entries "
+ "before %d)\n",
+ MAC_ARG(sta->addr), sta->aid,
+ 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()) {
+ printk(KERN_DEBUG "%s: STA " MAC_FMT " TX "
+ "buffer full - dropping oldest frame\n",
+ tx->dev->name, MAC_ARG(sta->addr));
+ }
+ 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)) {
+ printk(KERN_DEBUG "%s: STA " MAC_FMT " in PS mode, but pspoll "
+ "set -> send frame\n", tx->dev->name,
+ MAC_ARG(sta->addr));
+ }
+#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)
+{
+ if (unlikely(tx->u.tx.ps_buffered))
+ return TXRX_CONTINUE;
+
+ if (tx->u.tx.unicast)
+ 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)
+{
+ if (tx->sta)
+ tx->u.tx.control->key_idx = tx->sta->key_idx_compression;
+ else
+ tx->u.tx.control->key_idx = HW_KEY_IDX_INVALID;
+
+ if (unlikely(tx->u.tx.control->flags & IEEE80211_TXCTL_DO_NOT_ENCRYPT))
+ tx->key = NULL;
+ else if (tx->sta && tx->sta->key)
+ tx->key = tx->sta->key;
+ else if (tx->sdata->default_key)
+ tx->key = tx->sdata->default_key;
+ else if (tx->sdata->drop_unencrypted &&
+ !(tx->sdata->eapol && ieee80211_is_eapol(tx->skb))) {
+ I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
+ return TXRX_DROP;
+ } else
+ tx->key = NULL;
+
+ if (tx->key) {
+ tx->key->tx_rx_count++;
+ if (unlikely(tx->local->key_tx_rx_threshold &&
+ tx->key->tx_rx_count >
+ tx->local->key_tx_rx_threshold)) {
+ ieee80211_key_threshold_notify(tx->dev, tx->key,
+ tx->sta);
+ }
+ }
+
+ 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;
+
+ if (!tx->fragmented)
+ return TXRX_CONTINUE;
+
+ first = tx->skb;
+
+ hdrlen = ieee80211_get_hdrlen(tx->fc);
+ payload_len = first->len - hdrlen;
+ per_fragm = frag_threshold - hdrlen - FCS_LEN;
+ num_fragm = (payload_len + per_fragm - 1) / per_fragm;
+
+ 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 int wep_encrypt_skb(struct ieee80211_txrx_data *tx, struct sk_buff *skb)
+{
+ if (tx->key->force_sw_encrypt) {
+ if (ieee80211_wep_encrypt(tx->local, skb, tx->key))
+ return -1;
+ } else {
+ tx->u.tx.control->key_idx = tx->key->hw_key_idx;
+ if (tx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV) {
+ if (ieee80211_wep_add_iv(tx->local, skb, tx->key) ==
+ NULL)
+ return -1;
+ }
+ }
+ return 0;
+}
+
+static ieee80211_txrx_result
+ieee80211_tx_h_wep_encrypt(struct ieee80211_txrx_data *tx)
+{
+ struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
+ u16 fc;
+
+ fc = le16_to_cpu(hdr->frame_control);
+
+ if (!tx->key || tx->key->alg != ALG_WEP ||
+ ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
+ ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
+ (fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)))
+ return TXRX_CONTINUE;
+
+ tx->u.tx.control->iv_len = WEP_IV_LEN;
+ tx->u.tx.control->icv_len = WEP_ICV_LEN;
+ ieee80211_tx_set_iswep(tx);
+
+ if (wep_encrypt_skb(tx, tx->skb) < 0) {
+ I802_DEBUG_INC(tx->local->tx_handlers_drop_wep);
+ return TXRX_DROP;
+ }
+
+ if (tx->u.tx.extra_frag) {
+ int i;
+ for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
+ if (wep_encrypt_skb(tx, tx->u.tx.extra_frag[i]) < 0) {
+ I802_DEBUG_INC(tx->local->
+ tx_handlers_drop_wep);
+ return TXRX_DROP;
+ }
+ }
+ }
+
+ return TXRX_CONTINUE;
+}
+
+static ieee80211_txrx_result
+ieee80211_tx_h_rate_ctrl(struct ieee80211_txrx_data *tx)
+{
+ struct rate_control_extra extra;
+
+ memset(&extra, 0, sizeof(extra));
+ extra.mode = tx->u.tx.mode;
+ extra.mgmt_data = tx->sdata &&
+ tx->sdata->type == IEEE80211_IF_TYPE_MGMT;
+ extra.ethertype = tx->ethertype;
+
+ tx->u.tx.rate = rate_control_get_rate(tx->local, tx->dev, tx->skb,
+ &extra);
+ if (unlikely(extra.probe != NULL)) {
+ tx->u.tx.control->flags |= IEEE80211_TXCTL_RATE_CTRL_PROBE;
+ tx->u.tx.probe_last_frag = 1;
+ tx->u.tx.control->alt_retry_rate = tx->u.tx.rate->val;
+ tx->u.tx.rate = extra.probe;
+ } else {
+ tx->u.tx.control->alt_retry_rate = -1;
+ }
+ if (!tx->u.tx.rate)
+ return TXRX_DROP;
+ if (tx->u.tx.mode->mode == MODE_IEEE80211G &&
+ tx->sdata->use_protection && tx->fragmented &&
+ extra.nonerp) {
+ tx->u.tx.last_frag_rate = tx->u.tx.rate;
+ tx->u.tx.probe_last_frag = extra.probe ? 1 : 0;
+
+ tx->u.tx.rate = extra.nonerp;
+ tx->u.tx.control->rate = extra.nonerp;
+ 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;
+ if ((tx->u.tx.rate->flags & IEEE80211_RATE_PREAMBLE2) &&
+ tx->local->short_preamble &&
+ (!tx->sta || (tx->sta->flags & WLAN_STA_SHORT_PREAMBLE))) {
+ tx->u.tx.short_preamble = 1;
+ tx->u.tx.control->tx_rate = tx->u.tx.rate->val2;
+ }
+
+ 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;
+ u16 dur;
+ struct ieee80211_tx_control *control = tx->u.tx.control;
+ struct ieee80211_hw_mode *mode = tx->u.tx.mode;
+
+ 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->retry_limit =
+ tx->local->long_retry_limit;
+ } else {
+ control->retry_limit =
+ tx->local->short_retry_limit;
+ }
+ } else {
+ control->retry_limit = 1;
+ }
+
+ if (tx->fragmented) {
+ /* 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) &&
+ tx->u.tx.unicast && tx->sdata->use_protection &&
+ !(control->flags & IEEE80211_TXCTL_USE_RTS_CTS))
+ control->flags |= IEEE80211_TXCTL_USE_CTS_PROTECT;
+
+ /* 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),
+ tx->fragmented ? tx->u.tx.extra_frag[0]->len :
+ 0);
+ 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_ATHEROS_TURBO ||
+ mode->mode == MODE_ATHEROS_TURBOG ||
+ (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,
+ ieee80211_tx_h_tkip_encrypt,
+ ieee80211_tx_h_ccmp_encrypt,
+ ieee80211_tx_h_wep_encrypt,
+ 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
+__ieee80211_parse_tx_radiotap(
+ struct ieee80211_txrx_data *tx,
+ struct sk_buff *skb, struct ieee80211_tx_control *control)
+{
+ /*
+ * 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);
+
+ /*
+ * default control situation for all injected packets
+ * FIXME: this does not suit all usage cases, expand to allow control
+ */
+
+ control->retry_limit = 1; /* no retry */
+ control->key_idx = -1; /* no encryption key */
+ control->flags &= ~(IEEE80211_TXCTL_USE_RTS_CTS |
+ IEEE80211_TXCTL_USE_CTS_PROTECT);
+ control->flags |= IEEE80211_TXCTL_DO_NOT_ENCRYPT |
+ IEEE80211_TXCTL_NO_ACK;
+ control->antenna_sel_tx = 0; /* default to default antenna */
+
+ /*
+ * 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];
+
+ if (r->rate > target_rate)
+ continue;
+
+ control->rate = r;
+
+ if (r->flags & IEEE80211_RATE_PREAMBLE2)
+ control->tx_rate = r->val2;
+ else
+ control->tx_rate = r->val;
+
+ /* end on exact match */
+ if (r->rate == target_rate)
+ i = mode->num_rates;
+ }
+ 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);
+ }
+ break;
+
+ 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;
+}
+
+static ieee80211_txrx_result inline
+__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);
+ struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
+ 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);
+ tx->sta = sta_info_get(local, hdr->addr1);
+ tx->fc = le16_to_cpu(hdr->frame_control);
+
+ /*
+ * set defaults for things that can be set by
+ * injected radiotap headers
+ */
+ control->power_level = local->hw.conf.power_level;
+ control->antenna_sel_tx = local->hw.conf.antenna_sel_tx;
+ if (local->sta_antenna_sel != STA_ANTENNA_SEL_AUTO && tx->sta)
+ control->antenna_sel_tx = tx->sta->antenna_sel_tx;
+
+ /* process and remove the injection radiotap header */
+ sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+ if (unlikely(sdata->type == IEEE80211_IF_TYPE_MNTR)) {
+ if (__ieee80211_parse_tx_radiotap(tx, skb, control) ==
+ TXRX_DROP) {
+ return TXRX_DROP;
+ }
+ /*
+ * we removed the radiotap header after this point,
+ * we filled control with what we could use
+ * set to the actual ieee header now
+ */
+ hdr = (struct ieee80211_hdr *) skb->data;
+ res = TXRX_QUEUED; /* indication it was monitor packet */
+ }
+
+ tx->u.tx.control = control;
+ tx->u.tx.unicast = !is_multicast_ether_addr(hdr->addr1);
+ if (is_multicast_ether_addr(hdr->addr1))
+ control->flags |= IEEE80211_TXCTL_NO_ACK;
+ else
+ control->flags &= ~IEEE80211_TXCTL_NO_ACK;
+ tx->fragmented = local->fragmentation_threshold <
+ IEEE80211_MAX_FRAG_THRESHOLD && tx->u.tx.unicast &&
+ skb->len + FCS_LEN > local->fragmentation_threshold &&
+ (!local->ops->set_frag_threshold);
+ 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;
+ }
+ 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
+ * finished with it. */
+static int inline ieee80211_tx_prepare(struct ieee80211_txrx_data *tx,
+ struct sk_buff *skb,
+ struct net_device *mdev,
+ struct ieee80211_tx_control *control)
+{
+ struct ieee80211_tx_packet_data *pkt_data;
+ struct net_device *dev;
+
+ pkt_data = (struct ieee80211_tx_packet_data *)skb->cb;
+ dev = dev_get_by_index(pkt_data->ifindex);
+ if (unlikely(dev && !is_ieee80211_device(dev, mdev))) {
+ dev_put(dev);
+ dev = NULL;
+ }
+ if (unlikely(!dev))
+ return -ENODEV;
+ __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) {
+ ieee80211_dump_frame(local->mdev->name, "TX to low-level driver", skb);
+ 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;
+ if (tx->u.tx.probe_last_frag)
+ control->flags |=
+ IEEE80211_TXCTL_RATE_CTRL_PROBE;
+ else
+ control->flags &=
+ ~IEEE80211_TXCTL_RATE_CTRL_PROBE;
+ }
+
+ ieee80211_dump_frame(local->mdev->name,
+ "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,
+ struct ieee80211_tx_control *control, int mgmt)
+{
+ 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;
+ }
+
+ res_prepare = __ieee80211_tx_prepare(&tx, skb, dev, control);
+
+ if (res_prepare == TXRX_DROP) {
+ dev_kfree_skb(skb);
+ return 0;
+ }
+
+ sta = tx.sta;
+ tx.u.tx.mgmt_interface = mgmt;
+ tx.u.tx.mode = local->hw.conf.mode;
+
+ if (res_prepare == TXRX_QUEUED) { /* if it was an injected packet */
+ res = TXRX_CONTINUE;
+ } else {
+ for (handler = local->tx_handlers; *handler != NULL;
+ handler++) {
+ res = (*handler)(&tx);
+ if (res != TXRX_CONTINUE)
+ break;
+ }
+ }
+
+ 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);
+ 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;
+ store->last_frag_rate_ctrl_probe = tx.u.tx.probe_last_frag;
+ }
+ 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);
+ 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)
+ odev = dev_get_by_index(pkt_data->ifindex);
+ 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;
+ if (pkt_data->req_tx_status)
+ control.flags |= IEEE80211_TXCTL_REQ_TX_STATUS;
+ if (pkt_data->do_not_encrypt)
+ control.flags |= IEEE80211_TXCTL_DO_NOT_ENCRYPT;
+ if (pkt_data->requeue)
+ control.flags |= IEEE80211_TXCTL_REQUEUE;
+ control.queue = pkt_data->queue;
+
+ ret = ieee80211_tx(odev, skb, &control,
+ control.type == IEEE80211_IF_TYPE_MGMT);
+ 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;
+ u16 len;
+
+ /*
+ * there must be a radiotap header at the
+ * start in this case
+ */
+ if (unlikely(prthdr->it_version)) {
+ /* only version 0 is supported */
+ dev_kfree_skb(skb);
+ return NETDEV_TX_OK;
+ }
+
+ skb->dev = local->mdev;
+
+ pkt_data = (struct ieee80211_tx_packet_data *)skb->cb;
+ memset(pkt_data, 0, sizeof(*pkt_data));
+ pkt_data->ifindex = dev->ifindex;
+ pkt_data->mgmt_iface = 0;
+ pkt_data->do_not_encrypt = 1;
+
+ /* above needed because we set skb device to master */
+
+ /*
+ * 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
+ */
+ len = le16_to_cpu(get_unaligned(&prthdr->it_len));
+ skb_set_mac_header(skb, len);
+ skb_set_network_header(skb, len + sizeof(struct ieee80211_hdr));
+ skb_set_transport_header(skb, len + sizeof(struct ieee80211_hdr));
+
+ /*
+ * pass the radiotap header up to
+ * the next stage intact
+ */
+ dev_queue_xmit(skb);
+
+ return NETDEV_TX_OK;
+}
+
+/**
+ * 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;
+ int nh_pos, h_pos, no_encrypt = 0;
+ struct sta_info *sta;
+
+ 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];
+ /* TODO: handling for 802.1x authorized/unauthorized port */
+ fc = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA;
+
+ if (likely(sdata->type == IEEE80211_IF_TYPE_AP ||
+ sdata->type == IEEE80211_IF_TYPE_VLAN)) {
+ 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;
+ } else if (sdata->type == IEEE80211_IF_TYPE_WDS) {
+ 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;
+ } else if (sdata->type == IEEE80211_IF_TYPE_STA) {
+ 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;
+ } else if (sdata->type == IEEE80211_IF_TYPE_IBSS) {
+ /* 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;
+ } else {
+ ret = 0;
+ goto fail;
+ }
+
+ /* receiver is QoS enabled, use a QoS type frame */
+ sta = sta_info_get(local, hdr.addr1);
+ if (sta) {
+ if (sta->flags & WLAN_STA_WME) {
+ fc |= IEEE80211_STYPE_QOS_DATA;
+ hdrlen += 2;
+ }
+ sta_info_put(sta);
+ }
+
+ 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;
+ }
+ memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
+ 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;
+ pkt_data->mgmt_iface = (sdata->type == IEEE80211_IF_TYPE_MGMT);
+ pkt_data->do_not_encrypt = no_encrypt;
+
+ skb->dev = local->mdev;
+ sdata->stats.tx_packets++;
+ sdata->stats.tx_bytes += skb->len;
+
+ /* 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;
+}
+
+/*
+ * This is the transmit routine for the 802.11 type interfaces
+ * called by upper layers of the linux networking
+ * stack when it has a frame to transmit
+ */
+int ieee80211_mgmt_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ struct ieee80211_sub_if_data *sdata;
+ struct ieee80211_tx_packet_data *pkt_data;
+ struct ieee80211_hdr *hdr;
+ u16 fc;
+
+ sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+
+ if (skb->len < 10) {
+ dev_kfree_skb(skb);
+ return 0;
+ }
+
+ if (skb_headroom(skb) < sdata->local->tx_headroom) {
+ if (pskb_expand_head(skb, sdata->local->tx_headroom,
+ 0, GFP_ATOMIC)) {
+ dev_kfree_skb(skb);
+ return 0;
+ }
+ }
+
+ hdr = (struct ieee80211_hdr *) skb->data;
+ fc = le16_to_cpu(hdr->frame_control);
+
+ pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
+ memset(pkt_data, 0, sizeof(struct ieee80211_tx_packet_data));
+ pkt_data->ifindex = sdata->dev->ifindex;
+ pkt_data->mgmt_iface = (sdata->type == IEEE80211_IF_TYPE_MGMT);
+
+ skb->priority = 20; /* use hardcoded priority for mgmt TX queue */
+ skb->dev = sdata->local->mdev;
+
+ /*
+ * We're using the protocol field of the the frame control header
+ * to request TX callback for hostapd. BIT(1) is checked.
+ */
+ if ((fc & BIT(1)) == BIT(1)) {
+ pkt_data->req_tx_status = 1;
+ fc &= ~BIT(1);
+ hdr->frame_control = cpu_to_le16(fc);
+ }
+
+ pkt_data->do_not_encrypt = !(fc & IEEE80211_FCTL_PROTECTED);
+
+ sdata->stats.tx_packets++;
+ sdata->stats.tx_bytes += skb->len;
+
+ dev_queue_xmit(skb);
+
+ return 0;
+}
+
+/* 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;
+ tx.u.tx.probe_last_frag = store->last_frag_rate_ctrl_probe;
+ 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. */
+ spin_lock_bh(&local->sta_lock);
+ 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 */
+ }
+ spin_unlock_bh(&local->sta_lock);
+}
+
+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;
+ struct ieee80211_rate *rate;
+ struct rate_control_extra extra;
+ u8 *b_head, *b_tail;
+ int bh_len, bt_len;
+
+ bdev = dev_get_by_index(if_id);
+ 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);
+
+ ieee80211_include_sequence(sdata, (struct ieee80211_hdr *)skb->data);
+
+ ieee80211_beacon_add_tim(local, ap, skb);
+
+ if (b_tail) {
+ memcpy(skb_put(skb, bt_len), b_tail, bt_len);
+ }
+
+ if (control) {
+ memset(&extra, 0, sizeof(extra));
+ extra.mode = local->oper_hw_mode;
+
+ rate = rate_control_get_rate(local, local->mdev, skb, &extra);
+ if (!rate) {
+ if (net_ratelimit()) {
+ printk(KERN_DEBUG "%s: ieee80211_beacon_get: no rate "
+ "found\n", local->mdev->name);
+ }
+ dev_kfree_skb(skb);
+ return NULL;
+ }
+
+ control->tx_rate = (local->short_preamble &&
+ (rate->flags & IEEE80211_RATE_PREAMBLE2)) ?
+ rate->val2 : rate->val;
+ control->antenna_sel_tx = local->hw.conf.antenna_sel_tx;
+ control->power_level = local->hw.conf.power_level;
+ control->flags |= IEEE80211_TXCTL_NO_ACK;
+ control->retry_limit = 1;
+ control->flags |= IEEE80211_TXCTL_CLEAR_DST_MASK;
+ }
+
+ ap->num_beacons++;
+ return skb;
+}
+EXPORT_SYMBOL(ieee80211_beacon_get);
+
+void ieee80211_rts_get(struct ieee80211_hw *hw,
+ const void *frame, size_t frame_len,
+ const struct ieee80211_tx_control *frame_txctl,
+ struct ieee80211_rts *rts)
+{
+ const struct ieee80211_hdr *hdr = frame;
+ u16 fctl;
+
+ fctl = IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS;
+ rts->frame_control = cpu_to_le16(fctl);
+ rts->duration = ieee80211_rts_duration(hw, frame_len, frame_txctl);
+ memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
+ memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
+}
+EXPORT_SYMBOL(ieee80211_rts_get);
+
+void ieee80211_ctstoself_get(struct ieee80211_hw *hw,
+ const void *frame, size_t frame_len,
+ const struct ieee80211_tx_control *frame_txctl,
+ struct ieee80211_cts *cts)
+{
+ const struct ieee80211_hdr *hdr = frame;
+ u16 fctl;
+
+ fctl = IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS;
+ cts->frame_control = cpu_to_le16(fctl);
+ cts->duration = ieee80211_ctstoself_duration(hw, frame_len, frame_txctl);
+ memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
+}
+EXPORT_SYMBOL(ieee80211_ctstoself_get);
+
+struct sk_buff *
+ieee80211_get_buffered_bc(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 sta_info *sta;
+ ieee80211_tx_handler *handler;
+ struct ieee80211_txrx_data tx;
+ ieee80211_txrx_result res = TXRX_DROP;
+ struct net_device *bdev;
+ struct ieee80211_sub_if_data *sdata;
+ struct ieee80211_if_ap *bss = NULL;
+
+ bdev = dev_get_by_index(if_id);
+ if (bdev) {
+ sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
+ bss = &sdata->u.ap;
+ dev_put(bdev);
+ }
+ if (!bss || sdata->type != IEEE80211_IF_TYPE_AP || !bss->beacon_head)
+ return NULL;
+
+ if (bss->dtim_count != 0)
+ return NULL; /* send buffered bc/mc only after DTIM beacon */
+ memset(control, 0, sizeof(*control));
+ while (1) {
+ skb = skb_dequeue(&bss->ps_bc_buf);
+ if (!skb)
+ return NULL;
+ local->total_ps_buffered--;
+
+ if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) {
+ struct ieee80211_hdr *hdr =
+ (struct ieee80211_hdr *) skb->data;
+ /* more buffered multicast/broadcast frames ==> set
+ * MoreData flag in IEEE 802.11 header to inform PS
+ * STAs */
+ hdr->frame_control |=
+ cpu_to_le16(IEEE80211_FCTL_MOREDATA);
+ }
+
+ if (ieee80211_tx_prepare(&tx, skb, local->mdev, control) == 0)
+ break;
+ dev_kfree_skb_any(skb);
+ }
+ sta = tx.sta;
+ tx.u.tx.ps_buffered = 1;
+
+ for (handler = local->tx_handlers; *handler != NULL; handler++) {
+ res = (*handler)(&tx);
+ if (res == TXRX_DROP || res == TXRX_QUEUED)
+ break;
+ }
+ dev_put(tx.dev);
+ skb = tx.skb; /* handlers are allowed to change skb */
+
+ if (res == TXRX_DROP) {
+ I802_DEBUG_INC(local->tx_handlers_drop);
+ dev_kfree_skb(skb);
+ skb = NULL;
+ } else if (res == TXRX_QUEUED) {
+ I802_DEBUG_INC(local->tx_handlers_queued);
+ skb = NULL;
+ }
+
+ if (sta)
+ sta_info_put(sta);
+
+ return skb;
+}
+EXPORT_SYMBOL(ieee80211_get_buffered_bc);