1 files changed, 117 insertions, 23 deletions

diff --git a/net/mac80211/ieee80211.c b/net/mac80211/ieee80211.c
index 8b57eaa2a271..85f23fd866ad 100644
--- a/net/mac80211/ieee80211.c
+++ b/net/mac80211/ieee80211.c
@@ -57,6 +57,17 @@ static const unsigned char eapol_header[] =
 	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00, 0x88, 0x8e };
 
 
+/*
+ * For seeing transmitted packets on monitor interfaces
+ * we have a radiotap header too.
+ */
+struct ieee80211_tx_status_rtap_hdr {
+	struct ieee80211_radiotap_header hdr;
+	__le16 tx_flags;
+	u8 data_retries;
+} __attribute__ ((packed));
+
+
 static inline void ieee80211_include_sequence(struct ieee80211_sub_if_data *sdata,
 					      struct ieee80211_hdr *hdr)
 {
@@ -529,7 +540,7 @@ ieee80211_tx_h_fragment(struct ieee80211_txrx_data *tx)
 		/* reserve enough extra head and tail room for possible
 		 * encryption */
 		frag = frags[i] =
-			dev_alloc_skb(tx->local->hw.extra_tx_headroom +
+			dev_alloc_skb(tx->local->tx_headroom +
 				      frag_threshold +
 				      IEEE80211_ENCRYPT_HEADROOM +
 				      IEEE80211_ENCRYPT_TAILROOM);
@@ -538,8 +549,8 @@ ieee80211_tx_h_fragment(struct ieee80211_txrx_data *tx)
 		/* 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->hw.extra_tx_headroom +
-			IEEE80211_ENCRYPT_HEADROOM);
+		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)
@@ -1636,8 +1647,7 @@ static int ieee80211_master_start_xmit(struct sk_buff *skb,
 	}
 	osdata = IEEE80211_DEV_TO_SUB_IF(odev);
 
-	headroom = osdata->local->hw.extra_tx_headroom +
-		IEEE80211_ENCRYPT_HEADROOM;
+	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);
@@ -1833,7 +1843,7 @@ static int ieee80211_subif_start_xmit(struct sk_buff *skb,
 	 * build in headroom in __dev_alloc_skb() (linux/skbuff.h) and
 	 * alloc_skb() (net/core/skbuff.c)
 	 */
-	head_need = hdrlen + encaps_len + local->hw.extra_tx_headroom;
+	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
@@ -1920,9 +1930,9 @@ ieee80211_mgmt_start_xmit(struct sk_buff *skb, struct net_device *dev)
 		return 0;
 	}
 
-	if (skb_headroom(skb) < sdata->local->hw.extra_tx_headroom) {
-		if (pskb_expand_head(skb,
-		    sdata->local->hw.extra_tx_headroom, 0, GFP_ATOMIC)) {
+	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;
 		}
@@ -2061,12 +2071,12 @@ struct sk_buff * ieee80211_beacon_get(struct ieee80211_hw *hw, int if_id,
 	bh_len = ap->beacon_head_len;
 	bt_len = ap->beacon_tail_len;
 
-	skb = dev_alloc_skb(local->hw.extra_tx_headroom +
+	skb = dev_alloc_skb(local->tx_headroom +
 		bh_len + bt_len + 256 /* maximum TIM len */);
 	if (!skb)
 		return NULL;
 
-	skb_reserve(skb, local->hw.extra_tx_headroom);
+	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);
@@ -4498,6 +4508,9 @@ void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb,
 	struct ieee80211_local *local = hw_to_local(hw);
 	u16 frag, type;
 	u32 msg_type;
+	struct ieee80211_tx_status_rtap_hdr *rthdr;
+	struct ieee80211_sub_if_data *sdata;
+	int monitors;
 
 	if (!status) {
 		printk(KERN_ERR
@@ -4609,27 +4622,100 @@ void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb,
 			local->dot11FailedCount++;
 	}
 
-	if (!(status->control.flags & IEEE80211_TXCTL_REQ_TX_STATUS)
-	    || unlikely(!local->apdev)) {
+	msg_type = (status->flags & IEEE80211_TX_STATUS_ACK) ?
+		ieee80211_msg_tx_callback_ack : ieee80211_msg_tx_callback_fail;
+
+	/* this was a transmitted frame, but now we want to reuse it */
+	skb_orphan(skb);
+
+	if ((status->control.flags & IEEE80211_TXCTL_REQ_TX_STATUS) &&
+	    local->apdev) {
+		if (local->monitors) {
+			skb2 = skb_clone(skb, GFP_ATOMIC);
+		} else {
+			skb2 = skb;
+			skb = NULL;
+		}
+
+		if (skb2)
+			/* Send frame to hostapd */
+			ieee80211_rx_mgmt(local, skb2, NULL, msg_type);
+
+		if (!skb)
+			return;
+	}
+
+	if (!local->monitors) {
 		dev_kfree_skb(skb);
 		return;
 	}
 
-	msg_type = (status->flags & IEEE80211_TX_STATUS_ACK) ?
-		ieee80211_msg_tx_callback_ack : ieee80211_msg_tx_callback_fail;
+	/* send frame to monitor interfaces now */
 
-	/* skb was the original skb used for TX. Clone it and give the clone
-	 * to netif_rx(). Free original skb. */
-	skb2 = skb_copy(skb, GFP_ATOMIC);
-	if (!skb2) {
+	if (skb_headroom(skb) < sizeof(*rthdr)) {
+		printk(KERN_ERR "ieee80211_tx_status: headroom too small\n");
 		dev_kfree_skb(skb);
 		return;
 	}
-	dev_kfree_skb(skb);
-	skb = skb2;
 
-	/* Send frame to hostapd */
-	ieee80211_rx_mgmt(local, skb, NULL, msg_type);
+	rthdr = (struct ieee80211_tx_status_rtap_hdr*)
+				skb_push(skb, sizeof(*rthdr));
+
+	memset(rthdr, 0, sizeof(*rthdr));
+	rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
+	rthdr->hdr.it_present =
+		cpu_to_le32((1 << IEEE80211_RADIOTAP_TX_FLAGS) |
+			    (1 << IEEE80211_RADIOTAP_DATA_RETRIES));
+
+	if (!(status->flags & IEEE80211_TX_STATUS_ACK) &&
+	    !is_multicast_ether_addr(hdr->addr1))
+		rthdr->tx_flags |= cpu_to_le16(IEEE80211_RADIOTAP_F_TX_FAIL);
+
+	if ((status->control.flags & IEEE80211_TXCTL_USE_RTS_CTS) &&
+	    (status->control.flags & IEEE80211_TXCTL_USE_CTS_PROTECT))
+		rthdr->tx_flags |= cpu_to_le16(IEEE80211_RADIOTAP_F_TX_CTS);
+	else if (status->control.flags & IEEE80211_TXCTL_USE_RTS_CTS)
+		rthdr->tx_flags |= cpu_to_le16(IEEE80211_RADIOTAP_F_TX_RTS);
+
+	rthdr->data_retries = status->retry_count;
+
+	read_lock(&local->sub_if_lock);
+	monitors = local->monitors;
+	list_for_each_entry(sdata, &local->sub_if_list, list) {
+		/*
+		 * Using the monitors counter is possibly racy, but
+		 * if the value is wrong we simply either clone the skb
+		 * once too much or forget sending it to one monitor iface
+		 * The latter case isn't nice but fixing the race is much
+		 * more complicated.
+		 */
+		if (!monitors || !skb)
+			goto out;
+
+		if (sdata->type == IEEE80211_IF_TYPE_MNTR) {
+			if (!netif_running(sdata->dev))
+				continue;
+			monitors--;
+			if (monitors)
+				skb2 = skb_clone(skb, GFP_KERNEL);
+			else
+				skb2 = NULL;
+			skb->dev = sdata->dev;
+			/* XXX: is this sufficient for BPF? */
+			skb_set_mac_header(skb, 0);
+			skb->ip_summed = CHECKSUM_UNNECESSARY;
+			skb->pkt_type = PACKET_OTHERHOST;
+			skb->protocol = htons(ETH_P_802_2);
+			memset(skb->cb, 0, sizeof(skb->cb));
+			netif_rx(skb);
+			skb = skb2;
+			break;
+		}
+	}
+ out:
+	read_unlock(&local->sub_if_lock);
+	if (skb)
+		dev_kfree_skb(skb);
 }
 EXPORT_SYMBOL(ieee80211_tx_status);
 
@@ -4926,6 +5012,14 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
 		goto fail_workqueue;
 	}
 
+	/*
+	 * The hardware needs headroom for sending the frame,
+	 * and we need some headroom for passing the frame to monitor
+	 * interfaces, but never both at the same time.
+	 */
+	local->tx_headroom = max(local->hw.extra_tx_headroom,
+				 sizeof(struct ieee80211_tx_status_rtap_hdr));
+
 	debugfs_hw_add(local);
 
 	local->hw.conf.beacon_int = 1000;