aboutsummaryrefslogtreecommitdiffstats
path: root/net/bridge/br_netfilter.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/bridge/br_netfilter.c')
-rw-r--r--net/bridge/br_netfilter.c32
1 files changed, 32 insertions, 0 deletions
diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c
index ef1fe281ca11..a8361c7cdf81 100644
--- a/net/bridge/br_netfilter.c
+++ b/net/bridge/br_netfilter.c
@@ -892,6 +892,38 @@ static unsigned int ip_sabotage_in(const struct nf_hook_ops *ops,
return NF_ACCEPT;
}
+/* This is called when br_netfilter has called into iptables/netfilter,
+ * and DNAT has taken place on a bridge-forwarded packet.
+ *
+ * neigh->output has created a new MAC header, with local br0 MAC
+ * as saddr.
+ *
+ * This restores the original MAC saddr of the bridged packet
+ * before invoking bridge forward logic to transmit the packet.
+ */
+static void br_nf_pre_routing_finish_bridge_slow(struct sk_buff *skb)
+{
+ struct nf_bridge_info *nf_bridge = skb->nf_bridge;
+
+ skb_pull(skb, ETH_HLEN);
+ nf_bridge->mask &= ~BRNF_BRIDGED_DNAT;
+
+ skb_copy_to_linear_data_offset(skb, -(ETH_HLEN-ETH_ALEN),
+ skb->nf_bridge->data, ETH_HLEN-ETH_ALEN);
+ skb->dev = nf_bridge->physindev;
+ br_handle_frame_finish(skb);
+}
+
+int br_nf_prerouting_finish_bridge(struct sk_buff *skb)
+{
+ if (skb->nf_bridge && (skb->nf_bridge->mask & BRNF_BRIDGED_DNAT)) {
+ br_nf_pre_routing_finish_bridge_slow(skb);
+ return 1;
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(br_nf_prerouting_finish_bridge);
+
void br_netfilter_enable(void)
{
}