nat64_compose_ip6 (&ip6_saddr, &ip4->src_address, bibe->fib_index);
ste = nat64_db_st_entry_create (db, bibe, &ip6_saddr, &saddr.ip4, 0);
nat64_compose_ip6 (&ip6_saddr, &ip4->src_address, bibe->fib_index);
ste = nat64_db_st_entry_create (db, bibe, &ip6_saddr, &saddr.ip4, 0);