/*

 * 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.Asn1Exception;

import sun.security.krb5.internal.util.KerberosFlags;

import sun.security.util.*;

import java.io.IOException;

/**

 * Implements the ASN.1 APOptions type.

 *

 * <pre>{@code

 * APOptions    ::= KerberosFlags

 *      -- reserved(0),

 *      -- use-session-key(1),

 *      -- mutual-required(2)

 *

 * KerberosFlags   ::= BIT STRING (SIZE (32..MAX))

 *              -- minimum number of bits shall be sent,

 *              -- but no fewer than 32

 *

 * }</pre>

 * <p>

 * This definition reflects the Network Working Group RFC4120

 * specification available at

 * <a href="http://www.ietf.org/rfc/rfc4120.txt">

 * http://www.ietf.org/rfc/rfc4120.txt</a>.

 */

public class APOptions extends KerberosFlags {

    public APOptions() {

        super(Krb5.AP_OPTS_MAX + 1);

    }

    public APOptions(int oneBit) throws Asn1Exception {

        super(Krb5.AP_OPTS_MAX + 1);

        set(oneBit, true);

    }

    public APOptions(int size, byte[] data) throws Asn1Exception {

        super(size, data);

        if ((size > data.length * BITS_PER_UNIT) || (size > Krb5.AP_OPTS_MAX + 1)) {

            throw new Asn1Exception(Krb5.BITSTRING_BAD_LENGTH);

        }

    }

    public APOptions(boolean[] data) throws Asn1Exception {

        super(data);

        if (data.length > Krb5.AP_OPTS_MAX + 1) {

            throw new Asn1Exception(Krb5.BITSTRING_BAD_LENGTH);

        }

    }

    public APOptions(DerValue encoding) throws IOException, Asn1Exception {

        this(encoding.getUnalignedBitString(true).toBooleanArray());

    }

    /**

     * Parse (unmarshal) an APOptions from a DER input stream.  This form

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

     * a constructed sequence and uses explicitly tagged type.

     *

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

     * @param explicitTag tag number.

     * @param optional indicate if this data field is optional.

     * @return an instance of APOptions.

     * @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 static APOptions 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 APOptions(subDer);

        }

    }

}