/*

 * 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.util.*;

import sun.security.krb5.Asn1Exception;

import java.util.Vector;

import java.io.IOException;

import sun.security.krb5.internal.ccache.CCacheOutputStream;

/**

 * In RFC4120, the ASN.1 AuthorizationData is defined as:

 *

 * AuthorizationData            ::= SEQUENCE OF SEQUENCE {

 *              ad-type         [0] Int32,

 *              ad-data         [1] OCTET STRING

 * }

 *

 * Here, two classes are used to implement it and they can be represented as follows:

 *

 * AuthorizationData ::= SEQUENCE OF AuthorizationDataEntry

 * AuthorizationDataEntry ::= SEQUENCE {

 *              ad-type[0]  Int32,

 *              ad-data[1]  OCTET STRING

 * }

 */

public class AuthorizationData implements Cloneable {

    private AuthorizationDataEntry[] entry = null;

    private AuthorizationData() {

    }

    public AuthorizationData(AuthorizationDataEntry[] new_entries)

            throws IOException {

        if (new_entries != null) {

            entry = new AuthorizationDataEntry[new_entries.length];

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

                if (new_entries[i] == null) {

                    throw new IOException("Cannot create an AuthorizationData");

                } else {

                    entry[i] = (AuthorizationDataEntry) new_entries[i].clone();

                }

            }

        }

    }

    public AuthorizationData(AuthorizationDataEntry new_entry) {

        entry = new AuthorizationDataEntry[1];

        entry[0] = new_entry;

    }

    public Object clone() {

        AuthorizationData new_authorizationData =

                new AuthorizationData();

        if (entry != null) {

            new_authorizationData.entry =

                    new AuthorizationDataEntry[entry.length];

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

                new_authorizationData.entry[i] =

                        (AuthorizationDataEntry) entry[i].clone();

            }

        }

        return new_authorizationData;

    }

    /**

     * Constructs a new <code>AuthorizationData,</code> instance.

     * @param der 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.

     */

    public AuthorizationData(DerValue der) throws Asn1Exception, IOException {

        Vector<AuthorizationDataEntry> v = new Vector<>();

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

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

        }

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

            v.addElement(new AuthorizationDataEntry(der.getData().getDerValue()));

        }

        if (v.size() > 0) {

            entry = new AuthorizationDataEntry[v.size()];

            v.copyInto(entry);

        }

    }

    /**

     * Encodes an <code>AuthorizationData</code> object.

     * @return byte array of encoded <code>AuthorizationData</code> 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();

        DerValue[] der = new DerValue[entry.length];

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

            der[i] = new DerValue(entry[i].asn1Encode());

        }

        bytes.putSequence(der);

        return bytes.toByteArray();

    }

    /**

     * Parse (unmarshal) an <code>AuthorizationData</code> object from a DER input stream.

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

     * a constructed sequence and uses explicitly tagged 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.

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

     * @param explicitTag tag number.

     * @param optional indicates if this data field is optional

     * @return an instance of AuthorizationData.

     *

     */

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

        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 AuthorizationData(subDer);

        }

    }

    /**

     * Writes <code>AuthorizationData</code> data fields to a output stream.

     *

     * @param cos a <code>CCacheOutputStream</code> to be written to.

     * @exception IOException if an I/O exception occurs.

     */

    public void writeAuth(CCacheOutputStream cos) throws IOException {

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

            entry[i].writeEntry(cos);

        }

    }

    public String toString() {

        String retVal = "AuthorizationData:\n";

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

            retVal += entry[i].toString();

        }

        return retVal;

    }

    public int count() {

        return entry.length;

    }

    public AuthorizationDataEntry item(int i) {

        return (AuthorizationDataEntry)entry[i].clone();

    }

}