/*

 * Copyright 2000-2003 Sun Microsystems, Inc.  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.  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.

 */

package java.security.cert;

import java.io.IOException;

import sun.misc.HexDumpEncoder;

import sun.security.util.DerValue;

/**

 * An immutable policy qualifier represented by the ASN.1 PolicyQualifierInfo

 * structure.

 *

 * <p>The ASN.1 definition is as follows:

 * <p><pre>

 *   PolicyQualifierInfo ::= SEQUENCE {

 *        policyQualifierId       PolicyQualifierId,

 *        qualifier               ANY DEFINED BY policyQualifierId }

 * </pre>

 * <p>

 * A certificate policies extension, if present in an X.509 version 3

 * certificate, contains a sequence of one or more policy information terms,

 * each of which consists of an object identifier (OID) and optional

 * qualifiers. In an end-entity certificate, these policy information terms

 * indicate the policy under which the certificate has been issued and the

 * purposes for which the certificate may be used. In a CA certificate, these

 * policy information terms limit the set of policies for certification paths

 * which include this certificate.

 * <p>

 * A <code>Set</code> of <code>PolicyQualifierInfo</code> objects are returned

 * by the {@link PolicyNode#getPolicyQualifiers PolicyNode.getPolicyQualifiers}

 * method. This allows applications with specific policy requirements to

 * process and validate each policy qualifier. Applications that need to

 * process policy qualifiers should explicitly set the

 * <code>policyQualifiersRejected</code> flag to false (by calling the

 * {@link PKIXParameters#setPolicyQualifiersRejected

 * PKIXParameters.setPolicyQualifiersRejected} method) before validating

 * a certification path.

 *

 * <p>Note that the PKIX certification path validation algorithm specifies

 * that any policy qualifier in a certificate policies extension that is

 * marked critical must be processed and validated. Otherwise the

 * certification path must be rejected. If the

 * <code>policyQualifiersRejected</code> flag is set to false, it is up to

 * the application to validate all policy qualifiers in this manner in order

 * to be PKIX compliant.

 *

 * <p><b>Concurrent Access</b>

 *

 * <p>All <code>PolicyQualifierInfo</code> objects must be immutable and

 * thread-safe. That is, multiple threads may concurrently invoke the

 * methods defined in this class on a single <code>PolicyQualifierInfo</code>

 * object (or more than one) with no ill effects. Requiring

 * <code>PolicyQualifierInfo</code> objects to be immutable and thread-safe

 * allows them to be passed around to various pieces of code without

 * worrying about coordinating access.

 *

 * @author      seth proctor

 * @author      Sean Mullan

 * @since       1.4

 */

public class PolicyQualifierInfo {

    private byte [] mEncoded;

    private String mId;

    private byte [] mData;

    private String pqiString;

    /**

     * Creates an instance of <code>PolicyQualifierInfo</code> from the

     * encoded bytes. The encoded byte array is copied on construction.

     *

     * @param encoded a byte array containing the qualifier in DER encoding

     * @exception IOException thrown if the byte array does not represent a

     * valid and parsable policy qualifier

     */

    public PolicyQualifierInfo(byte[] encoded) throws IOException {

        mEncoded = encoded.clone();

        DerValue val = new DerValue(mEncoded);

        if (val.tag != DerValue.tag_Sequence)

            throw new IOException("Invalid encoding for PolicyQualifierInfo");

        mId = (val.data.getDerValue()).getOID().toString();

        byte [] tmp = val.data.toByteArray();

        if (tmp == null) {

            mData = null;

        } else {

            mData = new byte[tmp.length];

            System.arraycopy(tmp, 0, mData, 0, tmp.length);

        }

    }

    /**

     * Returns the <code>policyQualifierId</code> field of this

     * <code>PolicyQualifierInfo</code>. The <code>policyQualifierId</code>

     * is an Object Identifier (OID) represented by a set of nonnegative

     * integers separated by periods.

     *

     * @return the OID (never <code>null</code>)

     */

    public final String getPolicyQualifierId() {

        return mId;

    }

    /**

     * Returns the ASN.1 DER encoded form of this

     * <code>PolicyQualifierInfo</code>.

     *

     * @return the ASN.1 DER encoded bytes (never <code>null</code>).

     * Note that a copy is returned, so the data is cloned each time

     * this method is called.

     */

    public final byte[] getEncoded() {

        return mEncoded.clone();

    }

    /**

     * Returns the ASN.1 DER encoded form of the <code>qualifier</code>

     * field of this <code>PolicyQualifierInfo</code>.

     *

     * @return the ASN.1 DER encoded bytes of the <code>qualifier</code>

     * field. Note that a copy is returned, so the data is cloned each

     * time this method is called.

     */

    public final byte[] getPolicyQualifier() {

        return (mData == null ? null : mData.clone());

    }

    /**

     * Return a printable representation of this

     * <code>PolicyQualifierInfo</code>.

     *

     * @return a <code>String</code> describing the contents of this

     *         <code>PolicyQualifierInfo</code>

     */

    public String toString() {

        if (pqiString != null)

            return pqiString;

        HexDumpEncoder enc = new HexDumpEncoder();

        StringBuffer sb = new StringBuffer();

        sb.append("PolicyQualifierInfo: [\n");

        sb.append("  qualifierID: " + mId + "\n");

        sb.append("  qualifier: " +

            (mData == null ? "null" : enc.encodeBuffer(mData)) + "\n");

        sb.append("]");

        pqiString = sb.toString();

        return pqiString;

    }

}