/*

 * Copyright 2000-2006 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 sun.security.x509;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Enumeration;

import sun.security.util.Debug;

import sun.security.util.DerOutputStream;

import sun.security.util.DerValue;

import sun.security.util.ObjectIdentifier;

/**

 * This class represents the Inhibit Any-Policy Extension.

 *

 * <p>The inhibit any-policy extension can be used in certificates issued

 * to CAs. The inhibit any-policy indicates that the special any-policy

 * OID, with the value {2 5 29 32 0}, is not considered an explicit

 * match for other certificate policies.  The value indicates the number

 * of additional certificates that may appear in the path before any-

 * policy is no longer permitted.  For example, a value of one indicates

 * that any-policy may be processed in certificates issued by the sub-

 * ject of this certificate, but not in additional certificates in the

 * path.

 * <p>

 * This extension MUST be critical.

 * <p>

 * The ASN.1 syntax for this extension is:

 * <code><pre>

 * id-ce-inhibitAnyPolicy OBJECT IDENTIFIER ::=  { id-ce 54 }

 *

 * InhibitAnyPolicy ::= SkipCerts

 *

 * SkipCerts ::= INTEGER (0..MAX)

 * </pre></code>

 * @author Anne Anderson

 * @see CertAttrSet

 * @see Extension

 */

public class InhibitAnyPolicyExtension extends Extension

implements CertAttrSet<String> {

    private static final Debug debug = Debug.getInstance("certpath");

    /**

     * Identifier for this attribute, to be used with the

     * get, set, delete methods of Certificate, x509 type.

     */

    public static final String IDENT = "x509.info.extensions.InhibitAnyPolicy";

    /**

     * Object identifier for "any-policy"

     */

    public static ObjectIdentifier AnyPolicy_Id;

    static {

        try {

            AnyPolicy_Id = new ObjectIdentifier("2.5.29.32.0");

        } catch (IOException ioe) {

            // Should not happen

        }

    }

    /**

     * Attribute names.

     */

    public static final String NAME = "InhibitAnyPolicy";

    public static final String SKIP_CERTS = "skip_certs";

    // Private data members

    private int skipCerts = Integer.MAX_VALUE;

    // Encode this extension value

    private void encodeThis() throws IOException {

        DerOutputStream out = new DerOutputStream();

        out.putInteger(skipCerts);

        this.extensionValue = out.toByteArray();

    }

    /**

     * Default constructor for this object.

     *

     * @param skipCerts specifies the depth of the certification path.

     *                  Use value of -1 to request unlimited depth.

     */

    public InhibitAnyPolicyExtension(int skipCerts) throws IOException {

        if (skipCerts < -1)

            throw new IOException("Invalid value for skipCerts");

        if (skipCerts == -1)

            this.skipCerts = Integer.MAX_VALUE;

        else

            this.skipCerts = skipCerts;

        this.extensionId = PKIXExtensions.InhibitAnyPolicy_Id;

        critical = true;

        encodeThis();

    }

    /**

     * Create the extension from the passed DER encoded value of the same.

     *

     * @param critical criticality flag to use.  Must be true for this

     *                 extension.

     * @param value a byte array holding the DER-encoded extension value.

     * @exception ClassCastException if value is not an array of bytes

     * @exception IOException on error.

     */

    public InhibitAnyPolicyExtension(Boolean critical, Object value)

        throws IOException {

        this.extensionId = PKIXExtensions.InhibitAnyPolicy_Id;

        if (!critical.booleanValue())

            throw new IOException("Criticality cannot be false for " +

                                  "InhibitAnyPolicy");

        this.critical = critical.booleanValue();

        this.extensionValue = (byte[]) value;

        DerValue val = new DerValue(this.extensionValue);

        if (val.tag != DerValue.tag_Integer)

            throw new IOException("Invalid encoding of InhibitAnyPolicy: "

                                  + "data not integer");

        if (val.data == null)

            throw new IOException("Invalid encoding of InhibitAnyPolicy: "

                                  + "null data");

        int skipCertsValue = val.getInteger();

        if (skipCertsValue < -1)

            throw new IOException("Invalid value for skipCerts");

        if (skipCertsValue == -1) {

            this.skipCerts = Integer.MAX_VALUE;

        } else {

            this.skipCerts = skipCertsValue;

        }

    }

     /**

      * Return user readable form of extension.

      */

     public String toString() {

         String s = super.toString() + "InhibitAnyPolicy: " + skipCerts + "\n";

         return s;

     }

     /**

      * Encode this extension value to the output stream.

      *

      * @param out the DerOutputStream to encode the extension to.

      */

     public void encode(OutputStream out) throws IOException {

         DerOutputStream tmp = new DerOutputStream();

         if (extensionValue == null) {

             this.extensionId = PKIXExtensions.InhibitAnyPolicy_Id;

             critical = true;

             encodeThis();

         }

         super.encode(tmp);

         out.write(tmp.toByteArray());

     }

    /**

     * Set the attribute value.

     *

     * @param name name of attribute to set. Must be SKIP_CERTS.

     * @param obj  value to which attribute is to be set.  Must be Integer

     *             type.

     * @throws IOException on error

     */

    public void set(String name, Object obj) throws IOException {

        if (name.equalsIgnoreCase(SKIP_CERTS)) {

            if (!(obj instanceof Integer))

                throw new IOException("Attribute value should be of type Integer.");

            int skipCertsValue = ((Integer)obj).intValue();

            if (skipCertsValue < -1)

                throw new IOException("Invalid value for skipCerts");

            if (skipCertsValue == -1) {

                skipCerts = Integer.MAX_VALUE;

            } else {

                skipCerts = skipCertsValue;

            }

        } else

            throw new IOException("Attribute name not recognized by " +

                                  "CertAttrSet:InhibitAnyPolicy.");

        encodeThis();

    }

    /**

     * Get the attribute value.

     *

     * @param name name of attribute to get.  Must be SKIP_CERTS.

     * @returns value of the attribute.  In this case it will be of type

     *          Integer.

     * @throws IOException on error

     */

    public Object get(String name) throws IOException {

        if (name.equalsIgnoreCase(SKIP_CERTS))

            return (new Integer(skipCerts));

        else

            throw new IOException("Attribute name not recognized by " +

                                  "CertAttrSet:InhibitAnyPolicy.");

    }

    /**

     * Delete the attribute value.

     *

     * @param name name of attribute to delete. Must be SKIP_CERTS.

     * @throws IOException on error.  In this case, IOException will always be

     *                     thrown, because the only attribute, SKIP_CERTS, is

     *                     required.

     */

    public void delete(String name) throws IOException {

        if (name.equalsIgnoreCase(SKIP_CERTS))

            throw new IOException("Attribute " + SKIP_CERTS +

                                  " may not be deleted.");

        else

            throw new IOException("Attribute name not recognized by " +

                                  "CertAttrSet:InhibitAnyPolicy.");

    }

    /**

     * Return an enumeration of names of attributes existing within this

     * attribute.

     *

     * @returns enumeration of elements

     */

    public Enumeration<String> getElements() {

        AttributeNameEnumeration elements = new AttributeNameEnumeration();

        elements.addElement(SKIP_CERTS);

        return (elements.elements());

    }

    /**

     * Return the name of this attribute.

     *

     * @returns name of attribute.

     */

    public String getName() {

        return (NAME);

    }

}