/*
 * 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 java.util.Vector;
import sun.security.util.*;
import java.io.IOException;
import java.math.BigInteger;

/**
 * Implements the ASN.1 KRB_KDC_REQ type.
 *
 * <xmp>
 * 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
 * }
 * </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 KDCReq {
        public KDCReqBody reqBody;

        private int pvno;
        private int msgType;
        private PAData[] pAData = null; //optional

        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.
         * @exceptoin 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);
                subDer = der.getData().getDerValue();
                if ((subDer.getTag() & 0x01F) == 0x03) {
                        DerValue subsubDer = subDer.getData().getDerValue();
                        if (subsubDer.getTag() != DerValue.tag_SequenceOf) {
                                throw new Asn1Exception(Krb5.ASN1_BAD_ID);
                        }
                        Vector<PAData> v = new Vector<PAData> ();
                        while (subsubDer.getData().available() > 0) {
                                v.addElement(new PAData(subsubDer.getData().getDerValue()));
                        }
                        if (v.size() > 0) {
                                pAData = new PAData[v.size()];
                                v.copyInto(pAData);
                        }
                }
                else pAData = null;
                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);
        }

}