[PATCH nf-next v7 6/8] netfilter:nf_flow_table_ip: Support bridge family flow offload

[wenxu@xxxxxxxxx]

From: wenxu <wenxu@xxxxxxxxx>

With nf_conntrack_bridge function. The bridge family can do
conntrack it self. The flow offload function based on the
conntrack. This patch a bridge family operation in
nf_flow_table_ip.

Signed-off-by: wenxu <wenxu@xxxxxxxxx>
---
v7: rebase with upstream fix

 net/netfilter/nf_flow_table_ip.c | 64 ++++++++++++++++++++++++++++++++++++++--
 1 file changed, 62 insertions(+), 2 deletions(-)

diff --git a/net/netfilter/nf_flow_table_ip.c b/net/netfilter/nf_flow_table_ip.c
index 1c598af..6336f32 100644
--- a/net/netfilter/nf_flow_table_ip.c
+++ b/net/netfilter/nf_flow_table_ip.c
@@ -267,23 +267,59 @@ static int nf_flow_ipv4_xmit(struct flow_offload *flow, struct sk_buff *skb,
 	return NF_STOLEN;
 }
 
+static int  nf_flow_bridge_xmit(struct flow_offload *flow, struct sk_buff *skb,
+				enum flow_offload_tuple_dir dir)
+{
+	struct net_device *outdev;
+	u16 vlan_tag, vlan_proto;
+
+	vlan_tag = flow->tuplehash[dir].tuple.dst.dst_port.dst_vlan_tag;
+	vlan_proto = flow->tuplehash[dir].tuple.dst.dst_port.vlan_proto;
+	outdev = flow->tuplehash[dir].tuple.dst.dst_port.dev;
+	skb->dev = outdev;
+
+	if (vlan_tag)
+		__vlan_hwaccel_put_tag(skb, htons(vlan_proto), vlan_tag);
+	else
+		__vlan_hwaccel_clear_tag(skb);
+
+	skb_push(skb, ETH_HLEN);
+	if (!is_skb_forwardable(skb->dev, skb))
+		goto drop;
+
+	dev_queue_xmit(skb);
+	return NF_STOLEN;
+
+drop:
+	kfree_skb(skb);
+	return NF_STOLEN;
+}
+
 unsigned int
 nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb,
 			const struct nf_hook_state *state)
 {
 	struct flow_offload_tuple_rhash *tuplehash;
 	struct nf_flowtable *flow_table = priv;
+	int family = flow_table->type->family;
 	struct flow_offload_tuple tuple = {};
 	enum flow_offload_tuple_dir dir;
 	struct flow_offload *flow;
 	unsigned int thoff;
+	int ret;
 
 	if (skb->protocol != htons(ETH_P_IP))
 		return NF_ACCEPT;
 
+	if (family != NFPROTO_BRIDGE && family != NFPROTO_IPV4)
+		return NF_ACCEPT;
+
 	if (nf_flow_tuple_ip(skb, state->in, &tuple) < 0)
 		return NF_ACCEPT;
 
+	if (family == NFPROTO_BRIDGE && skb_vlan_tag_present(skb))
+		tuple.vlan_tag = skb_vlan_tag_get_id(skb);
+
 	tuplehash = flow_offload_lookup(flow_table, &tuple);
 	if (tuplehash == NULL)
 		return NF_ACCEPT;
@@ -305,8 +341,16 @@ static int nf_flow_ipv4_xmit(struct flow_offload *flow, struct sk_buff *skb,
 		return NF_DROP;
 
 	flow->timeout = (u32)jiffies + NF_FLOW_TIMEOUT;
+	switch (family) {
+	case NFPROTO_IPV4:
+		ret = nf_flow_ipv4_xmit(flow, skb, state, dir);
+		break;
+	case NFPROTO_BRIDGE:
+		ret = nf_flow_bridge_xmit(flow, skb, dir);
+		break;
+	}
 
-	return nf_flow_ipv4_xmit(flow, skb, state, dir);
+	return ret;
 }
 EXPORT_SYMBOL_GPL(nf_flow_offload_ip_hook);
 
@@ -511,16 +555,24 @@ static int nf_flow_ipv6_xmit(struct flow_offload *flow, struct sk_buff *skb,
 {
 	struct flow_offload_tuple_rhash *tuplehash;
 	struct nf_flowtable *flow_table = priv;
+	int family = flow_table->type->family;
 	struct flow_offload_tuple tuple = {};
 	enum flow_offload_tuple_dir dir;
 	struct flow_offload *flow;
+	int ret;
 
 	if (skb->protocol != htons(ETH_P_IPV6))
 		return NF_ACCEPT;
 
+	if (family != NFPROTO_BRIDGE && family != NFPROTO_IPV6)
+		return NF_ACCEPT;
+
 	if (nf_flow_tuple_ipv6(skb, state->in, &tuple) < 0)
 		return NF_ACCEPT;
 
+	if (family == NFPROTO_BRIDGE && skb_vlan_tag_present(skb))
+		tuple.vlan_tag = skb_vlan_tag_get_id(skb);
+
 	tuplehash = flow_offload_lookup(flow_table, &tuple);
 	if (tuplehash == NULL)
 		return NF_ACCEPT;
@@ -542,7 +594,15 @@ static int nf_flow_ipv6_xmit(struct flow_offload *flow, struct sk_buff *skb,
 		return NF_DROP;
 
 	flow->timeout = (u32)jiffies + NF_FLOW_TIMEOUT;
+	switch (family) {
+	case NFPROTO_IPV6:
+		ret = nf_flow_ipv6_xmit(flow, skb, state, dir);
+		break;
+	case NFPROTO_BRIDGE:
+		ret = nf_flow_bridge_xmit(flow, skb, dir);
+		break;
+	}
 
-	return nf_flow_ipv6_xmit(flow, skb, state, dir);
+	return ret;
 }
 EXPORT_SYMBOL_GPL(nf_flow_offload_ipv6_hook);
-- 
1.8.3.1