NegTokenInit negInit = new NegTokenInit(mechToken);
        byte[] krbToken = negInit.getMechanismToken();


        Path p = Files.createTempFile("fakeserver", ".keytab");
        try {
            Files.write(p, keyTab);
            KeyTab kt = KeyTab.getInstance(p.toFile());

            Assume.assumeTrue("Kerberos problem, clockskew?", false);
        }
    }


    public static Subject getInitiatorSubject ( KeyTab keytab, final KerberosPrincipal principal ) throws Asn1Exception, KrbException, IOException {
        KerberosTicket ticket = getKerberosTicket(keytab, principal);
        Set<Object> privCreds = new HashSet<>();
        privCreds.add(ticket);

/* HMACT64 keyed hashing algorithm
 * Copyright (C) 2003 "Eric Glass" <jcifs at samba dot org>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,

/* HMACT64 keyed hashing algorithm
 * Copyright (C) 2003 "Eric Glass" <jcifs at samba dot org>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,

     * 
     * This will require that a keytab is configured in this service.
     * 
     * 
     */
    public JAASAuthenticator () {
        this("jcifs");
    }


    /**
     * Create an authenticator using the given JAAS service
     * 
     * This will require that a keytab is configured in this service.
     * 
     * @param serviceName

import java.security.Key;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;

import javax.security.auth.Subject;
import javax.security.auth.kerberos.KerberosKey;
import javax.security.auth.kerberos.KeyTab;
import javax.security.auth.login.LoginContext;
import javax.security.auth.login.LoginException;


@SuppressWarnings ( "javadoc" )
public class KerberosCredentials {

    private Subject subject;