/*

 * 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.  Sun designates this

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

 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.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.*;

import sun.security.util.*;

import java.io.IOException;

import java.math.BigInteger;

/**

 * Implements the ASN.1 AP-REQ type.

 *

 * <xmp>

 * AP-REQ               ::= [APPLICATION 14] SEQUENCE {

 *      pvno            [0] INTEGER (5),

 *      msg-type        [1] INTEGER (14),

 *      ap-options      [2] APOptions,

 *      ticket          [3] Ticket,

 *      authenticator   [4] EncryptedData -- Authenticator

 * }

 * </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 APReq {

    public int pvno;

    public int msgType;

    public APOptions apOptions;

    public Ticket ticket;

    public EncryptedData authenticator;

    public APReq(

            APOptions new_apOptions,

            Ticket new_ticket,

            EncryptedData new_authenticator) {

        pvno = Krb5.PVNO;

        msgType = Krb5.KRB_AP_REQ;

        apOptions = new_apOptions;

        ticket = new_ticket;

        authenticator = new_authenticator;

    }

    public APReq(byte[] data) throws Asn1Exception, IOException, KrbApErrException, RealmException {

        init(new DerValue(data));

    }

    public APReq(DerValue encoding) throws Asn1Exception, IOException, KrbApErrException, RealmException {

        init(encoding);

    }

    /**

     * Initializes an APReq 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,

            IOException, KrbApErrException, RealmException {

        DerValue der, subDer;

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

                || (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);

        }

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

        if (pvno != Krb5.PVNO) {

            throw new KrbApErrException(Krb5.KRB_AP_ERR_BADVERSION);

        }

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

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

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

        }

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

        if (msgType != Krb5.KRB_AP_REQ) {

            throw new KrbApErrException(Krb5.KRB_AP_ERR_MSG_TYPE);

        }

        apOptions = APOptions.parse(der.getData(), (byte) 0x02, false);

        ticket = Ticket.parse(der.getData(), (byte) 0x03, false);

        authenticator = EncryptedData.parse(der.getData(), (byte) 0x04, false);

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

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

        }

    }

    /**

     * Encodes an APReq object.

     * @return byte array of encoded APReq 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();

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

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

        temp = new DerOutputStream();

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

        bytes.write(DerValue.createTag(DerValue.TAG_CONTEXT, true, (byte) 0x01), temp);

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

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

        bytes.write(DerValue.createTag(DerValue.TAG_CONTEXT, true, (byte) 0x04), authenticator.asn1Encode());

        temp = new DerOutputStream();

        temp.write(DerValue.tag_Sequence, bytes);

        DerOutputStream apreq = new DerOutputStream();

        apreq.write(DerValue.createTag(DerValue.TAG_APPLICATION, true, (byte) 0x0E), temp);

        return apreq.toByteArray();

    }

}