private AttributeTable getSignedAttributes() {
ASN1EncodableVector vec = new ASN1EncodableVector();
addAttribute(vec, ScepObjectIdentifiers.ID_MESSAGE_TYPE,
new DERPrintableString(Integer.toString(messageType.getCode())));
addAttribute(vec, ScepObjectIdentifiers.ID_SENDER_NONCE,
new DEROctetString(senderNonce.getBytes()));
addAttribute(vec, ScepObjectIdentifiers.ID_TRANSACTION_ID,
new DERPrintableString(transactionId.getId()));
addAttribute(vec, ScepObjectIdentifiers.ID_FAILINFO,
new DERPrintableString(Integer.toString(failInfo.getCode())));
addAttribute(vec, ScepObjectIdentifiers.ID_PKI_STATUS,
new DERPrintableString(Integer.toString(pkiStatus.getCode())));
addAttribute(vec, ScepObjectIdentifiers.ID_RECIPIENT_NONCE,
new DEROctetString(recipientNonce.getBytes()));
addAttribute(vec, type, signedAttributes.get(type));