crlnumberextension.java

来自「This is a resource based on j2me embedde」· Java 代码 · 共 220 行

/*
 * @(#)CRLNumberExtension.java	1.14 06/10/10
 *
 * Copyright  1990-2008 Sun Microsystems, Inc. All Rights Reserved.  
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER  
 *   
 * This program 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.   
 *   
 * This program 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 at /legal/license.txt).   
 *   
 * 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 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.InputStream;
import java.io.OutputStream;
import java.lang.reflect.Array;
import java.math.BigInteger;
import java.util.Enumeration;

import sun.security.util.*;

/**
 * Represent the CRL Number Extension.
 *
 * <p>This extension, if present, conveys a monotonically increasing
 * sequence number for each CRL issued by a given CA through a specific
 * CA X.500 Directory entry or CRL distribution point. This extension
 * allows users to easily determine when a particular CRL supersedes
 * another CRL.
 *
 * @author Hemma Prafullchandra
 * @version 1.7
 * @see Extension
 * @see CertAttrSet
 */
public class CRLNumberExtension extends Extension
implements CertAttrSet {

    /**
     * Attribute name.
     */
    public static final String NAME = "CRLNumber";
    public static final String NUMBER = "value";

    private BigInteger crlNumber = null;

    // Encode this extension value
    private void encodeThis() throws IOException {
        if (crlNumber == null) {
            this.extensionValue = null;
            return;
        }
        DerOutputStream os = new DerOutputStream();
        os.putInteger(this.crlNumber);
        this.extensionValue = os.toByteArray();
    }

    /**
     * Create a CRLNumberExtension with the integer value .
     * The criticality is set to false.
     *
     * @param crlNum the value to be set for the extension.
     */
    public CRLNumberExtension(int crlNum) throws IOException {
        this.crlNumber = BigInteger.valueOf(crlNum);
        this.extensionId = PKIXExtensions.CRLNumber_Id;
        this.critical = false;
        encodeThis();
    }

    /**
     * Create a CRLNumberExtension with the BigInteger value .
     * The criticality is set to false.
     *
     * @param crlNum the value to be set for the extension.
     */
    public CRLNumberExtension(BigInteger crlNum) throws IOException {
        this.crlNumber = crlNum;
        this.extensionId = PKIXExtensions.CRLNumber_Id;
        this.critical = false;
        encodeThis();
    }

    /**
     * Create the extension from the passed DER encoded value of the same.
     *
     * @param critical true if the extension is to be treated as critical.
     * @param value Array of DER encoded bytes of the actual value.
     * @exception IOException on error.
     */
    public CRLNumberExtension(Boolean critical, Object value)
    throws IOException {
        this.extensionId = PKIXExtensions.CRLNumber_Id;
        this.critical = critical.booleanValue();

        int len = Array.getLength(value);
	byte[] extValue = new byte[len];
	for (int i = 0; i < len; i++) {
	  extValue[i] = Array.getByte(value, i);
	}
        this.extensionValue = extValue;
        DerValue val = new DerValue(extValue);
        this.crlNumber = val.getBigInteger();
    }

    /**
     * Set the attribute value.
     */
    public void set(String name, Object obj) throws IOException {
	if (name.equalsIgnoreCase(NUMBER)) {
            if (!(obj instanceof BigInteger)) {
	        throw new IOException("Attribute must be of type BigInteger.");
	    }
            crlNumber = (BigInteger)obj;
	} else {
	  throw new IOException("Attribute name not recognized by"
                                + " CertAttrSet:CRLNumber.");
	}
        encodeThis();
    }

    /**
     * Get the attribute value.
     */
    public Object get(String name) throws IOException {
	if (name.equalsIgnoreCase(NUMBER)) {
            if (crlNumber == null) return null;
            else return crlNumber;
	} else {
	  throw new IOException("Attribute name not recognized by"
                                + " CertAttrSet:CRLNumber.");
	}
    }

    /**
     * Delete the attribute value.
     */
    public void delete(String name) throws IOException {
	if (name.equalsIgnoreCase(NUMBER)) {
            crlNumber = null;
	} else {
	  throw new IOException("Attribute name not recognized by"
                                + " CertAttrSet:CRLNumber.");
	}
        encodeThis();
    }

    /**
     * Returns a printable representation of the CRLNumberExtension.
     */
    public String toString() {
        String s = super.toString() + "CRL Number: " +
                   ((crlNumber == null) ? "" : Debug.toHexString(crlNumber))
                   + "\n";
        return (s);
    }

    /**
     * Decode the extension from the InputStream.
     *
     * @param in the InputStream to unmarshal the contents from.
     * @exception IOException on decoding or validity errors.
     */
    public void decode(InputStream in) throws IOException {
        throw new IOException("Method not to be called directly.");
    }

    /**
     * Write the extension to the DerOutputStream.
     *
     * @param out the DerOutputStream to write the extension to.
     * @exception IOException on encoding errors.
     */
    public void encode(OutputStream out) throws IOException {
       DerOutputStream	tmp = new DerOutputStream();

       if (this.extensionValue == null) {
           this.extensionId = PKIXExtensions.CRLNumber_Id;
           this.critical = true;
           encodeThis();
       }
       super.encode(tmp);
       out.write(tmp.toByteArray());
    }

    /**
     * Return an enumeration of names of attributes existing within this
     * attribute.
     */
    public Enumeration getElements() {
        AttributeNameEnumeration elements = new AttributeNameEnumeration();
        elements.addElement(NUMBER);
	return (elements.elements());
    }

    /**
     * Return the name of this attribute.
     */
    public String getName() {
        return (NAME);
    }
}