/*

 * 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.EncryptedData;

import sun.security.krb5.Asn1Exception;

import sun.security.krb5.RealmException;

import sun.security.util.*;

import java.util.Vector;

import java.io.IOException;

import java.math.BigInteger;

/**

 * Implements the ASN.1 Authenticator type.

 *

 * <xmp>

 * KRB-CRED     ::= [APPLICATION 22] SEQUENCE {

 *      pvno            [0] INTEGER (5),

 *      msg-type        [1] INTEGER (22),

 *      tickets         [2] SEQUENCE OF Ticket,

 *      enc-part        [3] EncryptedData -- EncKrbCredPart

 * }

 * </xmp>

 *

 * <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 KRBCred {

    public Ticket[] tickets = null;

    public EncryptedData encPart;

    private int pvno;

    private int msgType;

    public KRBCred(Ticket[] new_tickets, EncryptedData new_encPart) throws IOException {

        pvno = Krb5.PVNO;

        msgType = Krb5.KRB_CRED;

        if (new_tickets != null) {

            tickets = new Ticket[new_tickets.length];

            for (int i = 0; i < new_tickets.length; i++) {

                if (new_tickets[i] == null) {

                    throw new IOException("Cannot create a KRBCred");

                } else {

                    tickets[i] = (Ticket) new_tickets[i].clone();

                }

            }

        }

        encPart = new_encPart;

    }

    public KRBCred(byte[] data) throws Asn1Exception,

            RealmException, KrbApErrException, IOException {

        init(new DerValue(data));

    }

    public KRBCred(DerValue encoding) throws Asn1Exception,

            RealmException, KrbApErrException, IOException {

        init(encoding);

    }

    /**

     * Initializes an KRBCred 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 {

        if (((encoding.getTag() & (byte) 0x1F) != (byte) 0x16)

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

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

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

        }

        DerValue der, subDer;

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

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

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

        }

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

        if ((subDer.getTag() & 0x1F) == 0x00) {

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

            if (pvno != Krb5.PVNO) {

                throw new KrbApErrException(Krb5.KRB_AP_ERR_BADVERSION);

            }

        } else {

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

        }

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

        if ((subDer.getTag() & 0x1F) == 0x01) {

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

            if (msgType != Krb5.KRB_CRED) {

                throw new KrbApErrException(Krb5.KRB_AP_ERR_MSG_TYPE);

            }

        } else {

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

        }

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

        if ((subDer.getTag() & 0x1F) == 0x02) {

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

            if (subsubDer.getTag() != DerValue.tag_SequenceOf) {

                throw new Asn1Exception(Krb5.ASN1_BAD_ID);

            }

            while (subsubDer.getData().available() > 0) {

                v.addElement(new Ticket(subsubDer.getData().getDerValue()));

            }

            if (v.size() > 0) {

                tickets = new Ticket[v.size()];

                v.copyInto(tickets);

            }

        } else {

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

        }

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

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

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

        }

    }

    /**

     * Encodes an KRBCred object.

     * @return the data of encoded EncAPRepPart 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 temp, bytes, out;

        temp = new DerOutputStream();

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

        out = new DerOutputStream();

        out.write(DerValue.createTag(DerValue.TAG_CONTEXT,

                true, (byte) 0x00), temp);

        temp = new DerOutputStream();

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

        out.write(DerValue.createTag(DerValue.TAG_CONTEXT,

                true, (byte) 0x01), temp);

        temp = new DerOutputStream();

        for (int i = 0; i < tickets.length; i++) {

            temp.write(tickets[i].asn1Encode());

        }

        bytes = new DerOutputStream();

        bytes.write(DerValue.tag_SequenceOf, temp);

        out.write(DerValue.createTag(DerValue.TAG_CONTEXT,

                true, (byte) 0x02), bytes);

        out.write(DerValue.createTag(DerValue.TAG_CONTEXT,

                true, (byte) 0x03), encPart.asn1Encode());

        bytes = new DerOutputStream();

        bytes.write(DerValue.tag_Sequence, out);

        out = new DerOutputStream();

        out.write(DerValue.createTag(DerValue.TAG_APPLICATION,

                true, (byte) 0x16), bytes);

        return out.toByteArray();

    }

}