nf_ct_nat_ext_add
struct nf_conn_nat *nf_ct_nat_ext_add(struct nf_conn *ct);
nat = nf_ct_nat_ext_add(ct);
EXPORT_SYMBOL_GPL(nf_ct_nat_ext_add);
nat = nf_ct_nat_ext_add(ct);
nat = nf_ct_nat_ext_add(ct);
if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct))