X509_VERIFY_PARAM_get_flags
bak_flags = X509_VERIFY_PARAM_get_flags(tls_vpm);
unsigned long flags = vpm == NULL ? 0 : X509_VERIFY_PARAM_get_flags(vpm);
unsigned long X509_VERIFY_PARAM_get_flags(const X509_VERIFY_PARAM *param);
((x) == NULL || X509_VERIFY_PARAM_get_flags(X509_STORE_get0_param(x)) == 0)
&& (X509_VERIFY_PARAM_get_flags(vpm) & X509_V_FLAG_USE_CHECK_TIME) == 0
&& (X509_VERIFY_PARAM_get_flags(vpm) & X509_V_FLAG_NO_CHECK_TIME) != 0;