/*

 * Copyright (c) 2009, Oracle and/or its affiliates. All rights reserved.

 * 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

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package sun.security.krb5.internal.util;

import java.io.IOException;

import java.security.AccessController;

import sun.security.action.GetBooleanAction;

import sun.security.util.DerValue;

/**

 * Implements the ASN.1 KerberosString type.

 *

 * <pre>

 * KerberosString  ::= GeneralString (IA5String)

 * </pre>

 *

 * 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 final class KerberosString {

    /**

     * RFC 4120 defines KerberosString as GeneralString (IA5String), which

     * only includes ASCII characters. However, other implementations have been

     * known to use GeneralString to contain UTF-8 encoding. To interop

     * with these implementations, the following system property is defined.

     * When set as true, KerberosString is encoded as UTF-8. Note that this

     * only affects the byte encoding, the tag of the ASN.1 type is still

     * GeneralString.

     */

    public static final boolean MSNAME = AccessController.doPrivileged(

            new GetBooleanAction("sun.security.krb5.msinterop.kstring"));

    private final String s;

    public KerberosString(String s) {

        this.s = s;

    }

    public KerberosString(DerValue der) throws IOException {

        if (der.tag != DerValue.tag_GeneralString) {

            throw new IOException(

                "KerberosString's tag is incorrect: " + der.tag);

        }

        s = new String(der.getDataBytes(), MSNAME?"UTF8":"ASCII");

    }

    public String toString() {

        return s;

    }

    public DerValue toDerValue() throws IOException {

        // No need to cache the result since this method is

        // only called once.

        return new DerValue(DerValue.tag_GeneralString,

                s.getBytes(MSNAME?"UTF8":"ASCII"));

    }

}