cfg80211/mac80211: make ieee80211_send_layer2_update a public function

Make ieee80211_send_layer2_update() a common function so other drivers
can re-use it.

Signed-off-by: Dedy Lansky <dlansky@codeaurora.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 45 insertions, 0 deletions

diff --git a/net/wireless/util.c b/net/wireless/util.c
index e0825a019e9f..7bdcfe19b3ef 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -1893,3 +1893,48 @@ EXPORT_SYMBOL(rfc1042_header);
 const unsigned char bridge_tunnel_header[] __aligned(2) =
         { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
 EXPORT_SYMBOL(bridge_tunnel_header);
+
+/* Layer 2 Update frame (802.2 Type 1 LLC XID Update response) */
+struct iapp_layer2_update {
+        u8 da[ETH_ALEN];        /* broadcast */
+        u8 sa[ETH_ALEN];        /* STA addr */
+        __be16 len;             /* 6 */
+        u8 dsap;                /* 0 */
+        u8 ssap;                /* 0 */
+        u8 control;
+        u8 xid_info[3];
+} __packed;
+
+void cfg80211_send_layer2_update(struct net_device *dev, const u8 *addr)
+{
+        struct iapp_layer2_update *msg;
+        struct sk_buff *skb;
+
+        /* Send Level 2 Update Frame to update forwarding tables in layer 2
+         * bridge devices */
+
+        skb = dev_alloc_skb(sizeof(*msg));
+        if (!skb)
+                return;
+        msg = skb_put(skb, sizeof(*msg));
+
+        /* 802.2 Type 1 Logical Link Control (LLC) Exchange Identifier (XID)
+         * Update response frame; IEEE Std 802.2-1998, 5.4.1.2.1 */
+
+        eth_broadcast_addr(msg->da);
+        ether_addr_copy(msg->sa, addr);
+        msg->len = htons(6);
+        msg->dsap = 0;
+        msg->ssap = 0x01;       /* NULL LSAP, CR Bit: Response */
+        msg->control = 0xaf;    /* XID response lsb.1111F101.
+                                 * F=0 (no poll command; unsolicited frame) */
+        msg->xid_info[0] = 0x81;        /* XID format identifier */
+        msg->xid_info[1] = 1;   /* LLC types/classes: Type 1 LLC */
+        msg->xid_info[2] = 0;   /* XID sender's receive window size (RW) */
+
+        skb->dev = dev;
+        skb->protocol = eth_type_trans(skb, dev);
+        memset(skb->cb, 0, sizeof(skb->cb));
+        netif_rx_ni(skb);
+}
+EXPORT_SYMBOL(cfg80211_send_layer2_update);