diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 444fe6f..95a3d1f 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -5604,6 +5604,10 @@ struct bpf_tunnel_key {
 	__u8 tunnel_ttl;
 	__u16 tunnel_ext;	/* Padding, future use. */
 	__u32 tunnel_label;
+	union {
+		__u32 local_ipv4;
+		__u32 local_ipv6[4];
+	};
 };
 
 /* user accessible mirror of in-kernel xfrm_state.