KEY_DOM_DSA_SUBPRIME
copy_bigint_attr(&subprime, KEY_DOM_DSA_SUBPRIME(dom));
bigint_attr_cleanup(KEY_DOM_DSA_SUBPRIME(domain));
rv = copy_bigint(KEY_DOM_DSA_SUBPRIME(domain),
KEY_DOM_DSA_SUBPRIME(old_domain_obj_p));