/*

 * 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.*;

import java.util.Vector;

import sun.security.util.*;

import java.io.IOException;

import java.math.BigInteger;

/**

 * Implements the ASN.1 KRB_KDC_REQ type.

 *

 * <pre>{@code

 * KDC-REQ              ::= SEQUENCE {

 *      -- NOTE: first tag is [1], not [0]

 *      pvno            [1] INTEGER (5) ,

 *      msg-type        [2] INTEGER (10 -- AS -- | 12 -- TGS --),

 *      padata          [3] SEQUENCE OF PA-DATA OPTIONAL

 *                            -- NOTE: not empty --,

 *      req-body        [4] KDC-REQ-BODY

 * }

 * }</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 KDCReq {

    public KDCReqBody reqBody;

    public PAData[] pAData = null; //optional

    private int pvno;

    private int msgType;

    public KDCReq(PAData[] new_pAData, KDCReqBody new_reqBody,

            int req_type) throws IOException {

        pvno = Krb5.PVNO;

        msgType = req_type;

        if (new_pAData != null) {

            pAData = new PAData[new_pAData.length];

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

                if (new_pAData[i] == null) {

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

                } else {

                    pAData[i] = (PAData) new_pAData[i].clone();

                }

            }

        }

        reqBody = new_reqBody;

    }

    public KDCReq() {

    }

    public KDCReq(byte[] data, int req_type) throws Asn1Exception,

            IOException, KrbException {

        init(new DerValue(data), req_type);

    }

    /**

     * Creates an KDCReq object from a DerValue object and asn1 type.

     *

     * @param der a DER value of an KDCReq object.

     * @param req_type a encoded asn1 type 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 KrbErrException

     */

    public KDCReq(DerValue der, int req_type) throws Asn1Exception,

            IOException, KrbException {

        init(der, req_type);

    }

    /**

     * Initializes a KDCReq object from a DerValue.  The DER encoding

     * must be in the format specified by the KRB_KDC_REQ ASN.1 notation.

     *

     * @param encoding a DER-encoded KDCReq object.

     * @param req_type an int indicating whether it's KRB_AS_REQ or KRB_TGS_REQ type

     * @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 KrbException if an error occurs while constructing a Realm object,

     * or a Krb object from DER-encoded data.

     */

    protected void init(DerValue encoding, int req_type) throws Asn1Exception,

            IOException, KrbException {

        DerValue der, subDer;

        BigInteger bint;

        if ((encoding.getTag() & 0x1F) != req_type) {

            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() & 0x01F) == 0x01) {

            bint = subDer.getData().getBigInteger();

            this.pvno = bint.intValue();

            if (this.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() & 0x01F) == 0x02) {

            bint = subDer.getData().getBigInteger();

            this.msgType = bint.intValue();

            if (this.msgType != req_type) {

                throw new KrbApErrException(Krb5.KRB_AP_ERR_MSG_TYPE);

            }

        } else {

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

        }

        pAData = PAData.parseSequence(der.getData(), (byte) 0x03, true);

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

        if ((subDer.getTag() & 0x01F) == 0x04) {

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

            reqBody = new KDCReqBody(subsubDer, msgType);

        } else {

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

        }

    }

    /**

     * Encodes this object to a byte array.

     *

     * @return an byte array of encoded data.

     * @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) 0x01), temp);

        temp = new DerOutputStream();

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

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

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

        if (pAData != null && pAData.length > 0) {

            temp = new DerOutputStream();

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

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

            }

            bytes = new DerOutputStream();

            bytes.write(DerValue.tag_SequenceOf, temp);

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

                    true, (byte) 0x03), bytes);

        }

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

                true, (byte) 0x04), reqBody.asn1Encode(msgType));

        bytes = new DerOutputStream();

        bytes.write(DerValue.tag_Sequence, out);

        out = new DerOutputStream();

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

                true, (byte) msgType), bytes);

        return out.toByteArray();

    }

    public byte[] asn1EncodeReqBody() throws Asn1Exception, IOException {

        return reqBody.asn1Encode(msgType);

    }

}