/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/*

 *

 *  (C) Copyright IBM Corp. 1999 All Rights Reserved.

 *  Copyright 1997 The Open Group Research Institute.  All rights reserved.

 */

package sun.security.krb5.internal;

import sun.security.krb5.PrincipalName;

import sun.security.krb5.EncryptedData;

import sun.security.krb5.Asn1Exception;

import sun.security.krb5.Realm;

import sun.security.krb5.RealmException;

import sun.security.util.*;

import java.io.IOException;

import java.math.BigInteger;

/**

 * Implements the ASN.1 Ticket type.

 *

 * <pre>{@code

 * Ticket               ::= [APPLICATION 1] SEQUENCE {

 *      tkt-vno         [0] INTEGER (5),

 *      realm           [1] Realm,

 *      sname           [2] PrincipalName,

 *      enc-part        [3] EncryptedData -- EncTicketPart

 * }

 * }</pre>

 *

 * <p>

 * This definition reflects the Network Working Group RFC 4120

 * specification available at

 * <a href="http://www.ietf.org/rfc/rfc4120.txt">

 * http://www.ietf.org/rfc/rfc4120.txt</a>.

 */

public class Ticket implements Cloneable {

    public int tkt_vno;

    public PrincipalName sname;

    public EncryptedData encPart;

    private Ticket() {

    }

    public Object clone() {

        Ticket new_ticket = new Ticket();

        new_ticket.sname = (PrincipalName)sname.clone();

        new_ticket.encPart = (EncryptedData)encPart.clone();

        new_ticket.tkt_vno = tkt_vno;

        return new_ticket;

    }

    public Ticket(

                  PrincipalName new_sname,

                  EncryptedData new_encPart

                      ) {

        tkt_vno = Krb5.TICKET_VNO;

        sname = new_sname;

        encPart = new_encPart;

    }

    public Ticket(byte[] data) throws Asn1Exception,

    RealmException, KrbApErrException, IOException {

        init(new DerValue(data));

    }

    public Ticket(DerValue encoding) throws Asn1Exception,

    RealmException, KrbApErrException, IOException {

        init(encoding);

    }

    /**

     * Initializes a Ticket object.

     * @param encoding a single DER-encoded value.

     * @exception Asn1Exception if an error occurs while decoding an ASN1 encoded data.

     * @exception IOException if an I/O error occurs while reading encoded data.

     * @exception KrbApErrException if the value read from the DER-encoded data stream does not match the pre-defined value.

     * @exception RealmException if an error occurs while parsing a Realm object.

     */

    private void init(DerValue encoding) throws Asn1Exception,

    RealmException, KrbApErrException, IOException {

        DerValue der;

        DerValue subDer;

        if (((encoding.getTag() & (byte)0x1F) != Krb5.KRB_TKT)

            || (encoding.isApplication() != true)

            || (encoding.isConstructed() != true))

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

        der = encoding.getData().getDerValue();

        if (der.getTag() != DerValue.tag_Sequence)

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

        subDer = der.getData().getDerValue();

        if ((subDer.getTag() & (byte)0x1F) != (byte)0x00)

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

        tkt_vno = subDer.getData().getBigInteger().intValue();

        if (tkt_vno != Krb5.TICKET_VNO)

            throw new KrbApErrException(Krb5.KRB_AP_ERR_BADVERSION);

        Realm srealm = Realm.parse(der.getData(), (byte)0x01, false);

        sname = PrincipalName.parse(der.getData(), (byte)0x02, false, srealm);

        encPart = EncryptedData.parse(der.getData(), (byte)0x03, false);

        if (der.getData().available() > 0)

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

    }

    /**

     * Encodes a Ticket object.

     * @return byte array of encoded ticket object.

     * @exception Asn1Exception if an error occurs while decoding an ASN1 encoded data.

     * @exception IOException if an I/O error occurs while reading encoded data.

     */

    public byte[] asn1Encode() throws Asn1Exception, IOException {

        DerOutputStream bytes = new DerOutputStream();

        DerOutputStream temp = new DerOutputStream();

        DerValue[] der = new DerValue[4];

        temp.putInteger(BigInteger.valueOf(tkt_vno));

        bytes.write(DerValue.createTag(DerValue.TAG_CONTEXT, true, (byte)0x00), temp);

        bytes.write(DerValue.createTag(DerValue.TAG_CONTEXT, true, (byte)0x01), sname.getRealm().asn1Encode());

        bytes.write(DerValue.createTag(DerValue.TAG_CONTEXT, true, (byte)0x02), sname.asn1Encode());

        bytes.write(DerValue.createTag(DerValue.TAG_CONTEXT, true, (byte)0x03), encPart.asn1Encode());

        temp = new DerOutputStream();

        temp.write(DerValue.tag_Sequence, bytes);

        DerOutputStream ticket = new DerOutputStream();

        ticket.write(DerValue.createTag(DerValue.TAG_APPLICATION, true, (byte)0x01), temp);

        return ticket.toByteArray();

    }

    /**

     * Parse (unmarshal) a Ticket from a DER input stream.  This form

     * parsing might be used when expanding a value which is part of

     * a constructed sequence and uses explicitly tagged type.

     *

     * @exception Asn1Exception on error.

     * @param data the Der input stream value, which contains one or more marshaled value.

     * @param explicitTag tag number.

     * @param optional indicate if this data field is optional

     * @return an instance of Ticket.

     */

    public static Ticket parse(DerInputStream data, byte explicitTag, boolean optional) throws Asn1Exception, IOException, RealmException, KrbApErrException {

        if ((optional) && (((byte)data.peekByte() & (byte)0x1F)!= explicitTag))

            return null;

        DerValue der = data.getDerValue();

        if (explicitTag != (der.getTag() & (byte)0x1F))  {

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

        }

        else {

            DerValue subDer = der.getData().getDerValue();

            return new Ticket(subDer);

        }

    }

}