parentUser := "tls:" + certificate.Subject.CommonName

	claims[expClaim] = UTCNow().Add(expiry).Unix()
	claims[subClaim] = certificate.Subject.CommonName
	claims[audClaim] = certificate.Subject.Organization
	claims[issClaim] = certificate.Issuer.CommonName
	claims[parentClaim] = parentUser
	secretKey, err := getTokenSigningKey()
	if err != nil {
		writeSTSErrorResponse(ctx, w, ErrSTSInternalError, err)
		return