net/ipv4: Add helper to return path MTU based on fib result
Determine path MTU from a FIB lookup result. Logic is a distillation of
ip_dst_mtu_maybe_forward.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h
index 81d0f21..69c91d1 100644
--- a/include/net/ip_fib.h
+++ b/include/net/ip_fib.h
@@ -449,4 +449,6 @@ static inline void fib_proc_exit(struct net *net)
}
#endif
+u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr);
+
#endif /* _NET_FIB_H */
