netfilter: flow table support for the mixed IPv4/IPv6 family

This patch adds the IPv6 flow table type, that implements the datapath
flow table to forward IPv6 traffic.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

3 files changed, 57 insertions, 0 deletions

diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig
index 264ce877ef49..272803079bf2 100644
--- a/net/netfilter/Kconfig
+++ b/net/netfilter/Kconfig
@@ -657,6 +657,14 @@ endif # NF_TABLES_NETDEV
 
 endif # NF_TABLES
 
+config NF_FLOW_TABLE_INET
+	select NF_FLOW_TABLE
+	tristate "Netfilter flow table mixed IPv4/IPv6 module"
+	help
+          This option adds the flow table mixed IPv4/IPv6 support.
+
+	  To compile it as a module, choose M here.
+
 config NF_FLOW_TABLE
 	tristate "Netfilter flow table module"
 	help
diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile
index 2930f2b854be..061365875cde 100644
--- a/net/netfilter/Makefile
+++ b/net/netfilter/Makefile
@@ -111,6 +111,7 @@ obj-$(CONFIG_NFT_FWD_NETDEV)	+= nft_fwd_netdev.o
 
 # flow table infrastructure
 obj-$(CONFIG_NF_FLOW_TABLE)	+= nf_flow_table.o
+obj-$(CONFIG_NF_FLOW_TABLE_INET) += nf_flow_table_inet.o
 
 # generic X tables 
 obj-$(CONFIG_NETFILTER_XTABLES) += x_tables.o xt_tcpudp.o
diff --git a/net/netfilter/nf_flow_table_inet.c b/net/netfilter/nf_flow_table_inet.c
new file mode 100644
index 000000000000..281209aeba8f
--- /dev/null
+++ b/net/netfilter/nf_flow_table_inet.c
@@ -0,0 +1,48 @@
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/netfilter.h>
+#include <linux/rhashtable.h>
+#include <net/netfilter/nf_flow_table.h>
+#include <net/netfilter/nf_tables.h>
+
+static unsigned int
+nf_flow_offload_inet_hook(void *priv, struct sk_buff *skb,
+			  const struct nf_hook_state *state)
+{
+	switch (skb->protocol) {
+	case htons(ETH_P_IP):
+		return nf_flow_offload_ip_hook(priv, skb, state);
+	case htons(ETH_P_IPV6):
+		return nf_flow_offload_ipv6_hook(priv, skb, state);
+	}
+
+	return NF_ACCEPT;
+}
+
+static struct nf_flowtable_type flowtable_inet = {
+	.family		= NFPROTO_INET,
+	.params		= &nf_flow_offload_rhash_params,
+	.gc		= nf_flow_offload_work_gc,
+	.hook		= nf_flow_offload_inet_hook,
+	.owner		= THIS_MODULE,
+};
+
+static int __init nf_flow_inet_module_init(void)
+{
+	nft_register_flowtable_type(&flowtable_inet);
+
+	return 0;
+}
+
+static void __exit nf_flow_inet_module_exit(void)
+{
+	nft_unregister_flowtable_type(&flowtable_inet);
+}
+
+module_init(nf_flow_inet_module_init);
+module_exit(nf_flow_inet_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
+MODULE_ALIAS_NF_FLOWTABLE(1); /* NFPROTO_INET */