+#ifdef __KERNEL__
+#include <linux/skbuff.h>
+
+static inline struct icmp6hdr *icmp6_hdr(const struct sk_buff *skb)
+{
+ return (struct icmp6hdr *)skb_transport_header(skb);
+}
+#endif
+
+#define ICMPV6_ROUTER_PREF_LOW 0x3
+#define ICMPV6_ROUTER_PREF_MEDIUM 0x0
+#define ICMPV6_ROUTER_PREF_HIGH 0x1
+#define ICMPV6_ROUTER_PREF_INVALID 0x2