Message: fmt.Sprintf(
					"certificateRef %v/%v not accessible to a Gateway in namespace %q (missing a ReferenceGrant?)",
					tls.CertificateRefs[0].Name, credNs, namespace,
				),
			}
		}
		out.CredentialName = cred
	case k8s.TLSModePassthrough:
		out.Mode = istio.ServerTLSSettings_PASSTHROUGH
		if isAutoPassthrough {
			out.Mode = istio.ServerTLSSettings_AUTO_PASSTHROUGH
		}
	}
	return out, nil
}