var ret []pkix.Extension

	if (len(template.DNSNames) > 0 || len(template.EmailAddresses) > 0 || len(template.IPAddresses) > 0 || len(template.URIs) > 0) &&
		!oidInExtensions(oidExtensionSubjectAltName, template.ExtraExtensions) {
		sanBytes, err := marshalSANs(template.DNSNames, template.EmailAddresses, template.IPAddresses, template.URIs)
		if err != nil {
			return nil, err
		}