key4.fp_proto = FIB_PROTOCOL_IP4;
key4.fp_addr.ip4.as_u32 = fib_prefix.fp_addr.ip4.as_u32;
t = hash_get_mem (hm->dst_by_ip4, &key4);
key4.fp_proto = FIB_PROTOCOL_IP4;
key4.fp_addr.ip4.as_u32 = fib_prefix.fp_addr.ip4.as_u32;
t = hash_get_mem (hm->dst_by_ip4, &key4);