private void armorApRequest()

in kerby-kerb/kerb-server/src/main/java/org/apache/kerby/kerberos/kerb/server/request/KdcRequest.java [305:360]
50 lines of code
7 McCabe index (conditional complexity)

    private void armorApRequest(KrbFastArmor fastArmor) throws KrbException {
        if (fastArmor.getArmorType() == ArmorType.ARMOR_AP_REQUEST) {
            ApReq apReq;
            try {
                apReq = KrbCodec.decode(fastArmor.getArmorValue(), ApReq.class);
            } catch (KrbException e) {
                String errMessage = "Decode ApReq failed. " + e.getMessage();
                LOG.error(errMessage);
                throw new KrbException(errMessage);
            }

            Ticket ticket = apReq.getTicket();
            EncryptionType encType = ticket.getEncryptedEncPart().getEType();
            EncryptionKey tgsKey = getTgsEntry().getKeys().get(encType);
            if (ticket.getTktvno() != KrbConstant.KRB_V5) {
                LOG.error(KrbErrorCode.KRB_AP_ERR_BADVERSION.getMessage());
                throw new KrbException(KrbErrorCode.KRB_AP_ERR_BADVERSION);
            }

            EncTicketPart encPart = null;
            try {
                encPart = EncryptionUtil.unseal(ticket.getEncryptedEncPart(),
                    tgsKey, KeyUsage.KDC_REP_TICKET, EncTicketPart.class);
            } catch (KrbException e) {
                String errMessage = "Unseal EncTicketPart failed. " + e.getMessage();
                LOG.error(errMessage);
                throw new KrbException(errMessage);
            }
            ticket.setEncPart(encPart);

            EncryptionKey encKey = ticket.getEncPart().getKey();
            setSessionKey(encKey);

            Authenticator authenticator = null;
            try {
                authenticator = EncryptionUtil.unseal(apReq.getEncryptedAuthenticator(),
                    encKey, KeyUsage.AP_REQ_AUTH, Authenticator.class);
            } catch (KrbException e) {
                String errMessage = "Unseal Authenticator failed. " + e.getMessage();
                LOG.error(errMessage);
                throw new KrbException(errMessage);
            }

            EncryptionKey armorKey = null;
            try {
                armorKey = FastUtil.cf2(authenticator.getSubKey(), "subkeyarmor",
                    encKey, "ticketarmor");
            } catch (KrbException e) {
                String errMessage = "Create armor key failed. " + e.getMessage();
                LOG.error(errMessage);
                throw new KrbException(errMessage);
            }

            setArmorKey(armorKey);
        }
    }