1 files changed, 118 insertions, 0 deletions
diff --git a/net/bridge/netfilter/ebtable_nat.c b/net/bridge/netfilter/ebtable_nat.c
new file mode 100644
index 000000000..9066f7f37
--- /dev/null
+++ b/net/bridge/netfilter/ebtable_nat.c
@@ -0,0 +1,118 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  ebtable_nat
+ *
+ *	Authors:
+ *	Bart De Schuymer <bdschuym@pandora.be>
+ *
+ *  April, 2002
+ *
+ */
+
+#include <linux/netfilter_bridge/ebtables.h>
+#include <uapi/linux/netfilter_bridge.h>
+#include <linux/module.h>
+
+#define NAT_VALID_HOOKS ((1 << NF_BR_PRE_ROUTING) | (1 << NF_BR_LOCAL_OUT) | \
+			 (1 << NF_BR_POST_ROUTING))
+
+static struct ebt_entries initial_chains[] = {
+	{
+		.name	= "PREROUTING",
+		.policy	= EBT_ACCEPT,
+	},
+	{
+		.name	= "OUTPUT",
+		.policy	= EBT_ACCEPT,
+	},
+	{
+		.name	= "POSTROUTING",
+		.policy	= EBT_ACCEPT,
+	}
+};
+
+static struct ebt_replace_kernel initial_table = {
+	.name		= "nat",
+	.valid_hooks	= NAT_VALID_HOOKS,
+	.entries_size	= 3 * sizeof(struct ebt_entries),
+	.hook_entry	= {
+		[NF_BR_PRE_ROUTING]	= &initial_chains[0],
+		[NF_BR_LOCAL_OUT]	= &initial_chains[1],
+		[NF_BR_POST_ROUTING]	= &initial_chains[2],
+	},
+	.entries	= (char *)initial_chains,
+};
+
+static const struct ebt_table frame_nat = {
+	.name		= "nat",
+	.table		= &initial_table,
+	.valid_hooks	= NAT_VALID_HOOKS,
+	.me		= THIS_MODULE,
+};
+
+static const struct nf_hook_ops ebt_ops_nat[] = {
+	{
+		.hook		= ebt_do_table,
+		.pf		= NFPROTO_BRIDGE,
+		.hooknum	= NF_BR_LOCAL_OUT,
+		.priority	= NF_BR_PRI_NAT_DST_OTHER,
+	},
+	{
+		.hook		= ebt_do_table,
+		.pf		= NFPROTO_BRIDGE,
+		.hooknum	= NF_BR_POST_ROUTING,
+		.priority	= NF_BR_PRI_NAT_SRC,
+	},
+	{
+		.hook		= ebt_do_table,
+		.pf		= NFPROTO_BRIDGE,
+		.hooknum	= NF_BR_PRE_ROUTING,
+		.priority	= NF_BR_PRI_NAT_DST_BRIDGED,
+	},
+};
+
+static int frame_nat_table_init(struct net *net)
+{
+	return ebt_register_table(net, &frame_nat, ebt_ops_nat);
+}
+
+static void __net_exit frame_nat_net_pre_exit(struct net *net)
+{
+	ebt_unregister_table_pre_exit(net, "nat");
+}
+
+static void __net_exit frame_nat_net_exit(struct net *net)
+{
+	ebt_unregister_table(net, "nat");
+}
+
+static struct pernet_operations frame_nat_net_ops = {
+	.exit = frame_nat_net_exit,
+	.pre_exit = frame_nat_net_pre_exit,
+};
+
+static int __init ebtable_nat_init(void)
+{
+	int ret = ebt_register_template(&frame_nat, frame_nat_table_init);
+
+	if (ret)
+		return ret;
+
+	ret = register_pernet_subsys(&frame_nat_net_ops);
+	if (ret) {
+		ebt_unregister_template(&frame_nat);
+		return ret;
+	}
+
+	return ret;
+}
+
+static void __exit ebtable_nat_fini(void)
+{
+	unregister_pernet_subsys(&frame_nat_net_ops);
+	ebt_unregister_template(&frame_nat);
+}
+
+module_init(ebtable_nat_init);
+module_exit(ebtable_nat_fini);
+MODULE_LICENSE("GPL");