mac80211: adding 802.11n essential A-MSDU Rx capability
This patch adds the ability to receive and handle A-MSDU frames.
Signed-off-by: Ron Rindjunsky <ron.rindjunsky@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 478d855..4525d73 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -243,6 +243,10 @@
u8 *qc = data + ieee80211_get_hdrlen(rx->fc) - QOS_CONTROL_LEN;
/* frame has qos control */
tid = qc[0] & QOS_CONTROL_TID_MASK;
+ if (qc[0] & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
+ rx->u.rx.amsdu_frame = 1;
+ else
+ rx->u.rx.amsdu_frame = 0;
} else {
if (unlikely((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT)) {
/* Separate TID for management frames */
@@ -1197,6 +1201,125 @@
}
static ieee80211_txrx_result
+ieee80211_rx_h_amsdu(struct ieee80211_txrx_data *rx)
+{
+ struct net_device *dev = rx->dev;
+ struct ieee80211_local *local = rx->local;
+ u16 fc, ethertype;
+ u8 *payload;
+ struct sk_buff *skb = rx->skb, *frame = NULL;
+ const struct ethhdr *eth;
+ int remaining, err;
+ u8 dst[ETH_ALEN];
+ u8 src[ETH_ALEN];
+ DECLARE_MAC_BUF(mac);
+
+ fc = rx->fc;
+ if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
+ return TXRX_CONTINUE;
+
+ if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
+ return TXRX_DROP;
+
+ if (!rx->u.rx.amsdu_frame)
+ return TXRX_CONTINUE;
+
+ err = ieee80211_data_to_8023(rx);
+ if (unlikely(err))
+ return TXRX_DROP;
+
+ skb->dev = dev;
+
+ dev->stats.rx_packets++;
+ dev->stats.rx_bytes += skb->len;
+
+ /* skip the wrapping header */
+ eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
+ if (!eth)
+ return TXRX_DROP;
+
+ while (skb != frame) {
+ u8 padding;
+ __be16 len = eth->h_proto;
+ unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
+
+ remaining = skb->len;
+ memcpy(dst, eth->h_dest, ETH_ALEN);
+ memcpy(src, eth->h_source, ETH_ALEN);
+
+ padding = ((4 - subframe_len) & 0x3);
+ /* the last MSDU has no padding */
+ if (subframe_len > remaining) {
+ printk(KERN_DEBUG "%s: wrong buffer size", dev->name);
+ return TXRX_DROP;
+ }
+
+ skb_pull(skb, sizeof(struct ethhdr));
+ /* if last subframe reuse skb */
+ if (remaining <= subframe_len + padding)
+ frame = skb;
+ else {
+ frame = dev_alloc_skb(local->hw.extra_tx_headroom +
+ subframe_len);
+
+ if (frame == NULL)
+ return TXRX_DROP;
+
+ skb_reserve(frame, local->hw.extra_tx_headroom +
+ sizeof(struct ethhdr));
+ memcpy(skb_put(frame, ntohs(len)), skb->data,
+ ntohs(len));
+
+ eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
+ padding);
+ if (!eth) {
+ printk(KERN_DEBUG "%s: wrong buffer size ",
+ dev->name);
+ dev_kfree_skb(frame);
+ return TXRX_DROP;
+ }
+ }
+
+ skb_set_network_header(frame, 0);
+ frame->dev = dev;
+ frame->priority = skb->priority;
+ rx->skb = frame;
+
+ if ((ieee80211_drop_802_1x_pae(rx, 0)) ||
+ (ieee80211_drop_unencrypted(rx, 0))) {
+ if (skb == frame) /* last frame */
+ return TXRX_DROP;
+ dev_kfree_skb(frame);
+ continue;
+ }
+
+ payload = frame->data;
+ ethertype = (payload[6] << 8) | payload[7];
+
+ if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
+ ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
+ compare_ether_addr(payload,
+ bridge_tunnel_header) == 0)) {
+ /* remove RFC1042 or Bridge-Tunnel
+ * encapsulation and replace EtherType */
+ skb_pull(frame, 6);
+ memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
+ memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
+ } else {
+ memcpy(skb_push(frame, sizeof(__be16)), &len,
+ sizeof(__be16));
+ memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
+ memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
+ }
+
+
+ ieee80211_deliver_skb(rx);
+ }
+
+ return TXRX_QUEUED;
+}
+
+static ieee80211_txrx_result
ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
{
struct net_device *dev = rx->dev;
@@ -1379,6 +1502,7 @@
* are not passed to user space by these functions
*/
ieee80211_rx_h_remove_qos_control,
+ ieee80211_rx_h_amsdu,
ieee80211_rx_h_data,
ieee80211_rx_h_mgmt,
NULL