tgs.Task.java Source code

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Here is the source code for tgs.Task.java

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/*
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package tgs;

import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.Socket;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.crypto.Cipher;
import javax.crypto.SealedObject;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import m18.kerberos.as.TicketTCTGS;
import m18.kerberos.exceptions.BadChecksumException;
import m18.kerberos.exceptions.BadTimestampException;
import m18.kerberos.tgs.AuthenticatorTGS;
import m18.kerberos.tgs.KCS;
import m18.kerberos.tgs.TGSReply;
import m18.kerberos.tgs.TGSRequest;
import m18.kerberos.tgs.TicketCS;
import org.joda.time.DateTime;
import org.joda.time.Period;

/**
 *
 * @author Thibault
 */
public class Task implements Runnable {
    private Socket cSock;
    private ObjectOutputStream oos;
    private ObjectInputStream ois;

    private SecretKey KCTGS;

    public Task(Socket s) {
        cSock = s;
    }

    @Override
    public void run() {
        try {
            oos = new ObjectOutputStream(cSock.getOutputStream());
            ois = new ObjectInputStream(cSock.getInputStream());

            // Chargement cl symtrique KTGS
            SecretKey KTGS = new SecretKeySpec("cisco123".getBytes(), "DES");

            // Rcupration de l'objet
            TGSRequest TGSreq = (TGSRequest) ois.readObject();

            // Dcryptage de l'objet TGSRequest avec la cl symtrique KTGS
            Cipher cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
            cipher.init(Cipher.DECRYPT_MODE, KTGS);
            TicketTCTGS ticket = (TicketTCTGS) TGSreq.getTicket().getObject(cipher);

            // Rcupration cl de session KCTGS
            KCTGS = ticket.getKctgsSessionKey();

            // Reinitialisation du cipher avec la KCTGS
            cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
            cipher.init(Cipher.DECRYPT_MODE, KCTGS);

            // Dcryptage de l'authentificateur
            AuthenticatorTGS auth = (AuthenticatorTGS) TGSreq.getAuthenticator().getObject(cipher);

            // Vrification checksum
            if (auth.getClientName().hashCode() != auth.getChecksum())
                throw new BadChecksumException();

            // Verification timestamp
            DateTime valid = new DateTime(ticket.getTimeValid().getTime());
            DateTime current = new DateTime(auth.getCurrentTime().getTime());
            Period diff = new Period(valid, current);
            if (diff.getHours() > 8)
                throw new BadTimestampException();

            // Construction TGS Reply
            SecretKey kcsKey = new SecretKeySpec("cisco456".getBytes(), "DES");
            SecretKey KS = new SecretKeySpec("cisco789".getBytes(), "DES");

            KCS kcs = new KCS();
            kcs.setClientName(auth.getClientName());
            kcs.setValidity(ticket.getTimeValid());
            kcs.setKcs(kcsKey);
            cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
            cipher.init(Cipher.ENCRYPT_MODE, KS);
            SealedObject soKCS = new SealedObject(kcs, cipher);

            TicketCS tick = new TicketCS();
            tick.setService(TGSreq.getService());
            tick.setKCS(soKCS);

            cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
            cipher.init(Cipher.ENCRYPT_MODE, KCTGS);

            SealedObject soKCSkeyOnly = new SealedObject(kcsKey, cipher);

            TGSReply TGSrep = new TGSReply();
            TGSrep.setKCSkey(soKCSkeyOnly);
            TGSrep.setTicket(tick);

            oos.writeObject(TGSrep);

        } catch (BadChecksumException ex) {
            System.out.println("BadCheckSumExc");
        } catch (BadTimestampException ex) {
            System.out.println("BadTimeStampExc");
        } catch (Exception ex) {
            Logger.getLogger(Task.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}