[PATCH 297/510] Staging: batman-adv: best gw DHCP filter 802.1Q support

[Greg Kroah-Hartman]

From: Marek Lindner <lindner_marek at yahoo.de>

The DHCP filter inspects packets to determine whether or not to send
them via ethernet unicast. This patch adds 802.1Q (vlan) support for
this check.

Signed-off-by: Marek Lindner <lindner_marek at yahoo.de>
[sven.eckelmann at gmx.de: Rework on top of current version]
Signed-off-by: Sven Eckelmann <sven.eckelmann at gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh at suse.de>
---
 drivers/staging/batman-adv/gateway_client.c |    8 ++++++++
 1 files changed, 8 insertions(+), 0 deletions(-)

diff --git a/drivers/staging/batman-adv/gateway_client.c b/drivers/staging/batman-adv/gateway_client.c
index 3d4e109..fde1d8a 100644
--- a/drivers/staging/batman-adv/gateway_client.c
+++ b/drivers/staging/batman-adv/gateway_client.c
@@ -415,6 +415,14 @@ int gw_is_target(struct bat_priv *bat_priv, struct sk_buff *skb)
 	ethhdr = (struct ethhdr *)skb->data;
 	header_len += ETH_HLEN;
 
+	/* check for initial vlan header */
+	if (ntohs(ethhdr->h_proto) == ETH_P_8021Q) {
+		if (!pskb_may_pull(skb, header_len + VLAN_HLEN))
+			return 0;
+		ethhdr = (struct ethhdr *)(skb->data + VLAN_HLEN);
+		header_len += VLAN_HLEN;
+	}
+
 	/* check for ip header */
 	if (ntohs(ethhdr->h_proto) != ETH_P_IP)
 		return 0;
-- 
1.7.3.2