KeyDescriptorMetaDataBuilder.java

/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2008, Red Hat Middleware LLC, and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.picketlink.identity.federation.api.saml.v2.metadata;

import static org.picketlink.identity.federation.core.util.StringUtil.isNotNull;

import java.math.BigInteger;

import org.picketlink.identity.federation.PicketLinkLogger;
import org.picketlink.identity.federation.PicketLinkLoggerFactory;
import org.picketlink.identity.federation.core.saml.v2.constants.JBossSAMLConstants;
import org.picketlink.identity.federation.core.saml.v2.constants.JBossSAMLURIConstants;
import org.picketlink.identity.federation.saml.v2.metadata.KeyDescriptorType;
import org.picketlink.identity.federation.saml.v2.metadata.KeyTypes;
import org.picketlink.identity.xmlsec.w3.xmlenc.EncryptionMethodType;
import org.picketlink.identity.xmlsec.w3.xmlenc.EncryptionMethodType.EncryptionMethod;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;

/**
 * MetaDataBuilder for the KeyDescriptor
 *
 * @author Anil.Saldhana@redhat.com
 * @since Apr 20, 2009
 */
public class KeyDescriptorMetaDataBuilder {
    
    private static final PicketLinkLogger logger = PicketLinkLoggerFactory.getLogger();
    
    /**
     * Create a Key Descriptor
     *
     * @param keyInfo
     * @param algorithm
     * @param keySize
     * @param isSigningKey Whether the key is for signing
     * @param isEncryptionKey Whether the key is for encryption
     * @throws {@link IllegalArgumentException} when keyinfo is null
     * @throws {@link IllegalArgumentException} when both the parameters "isSigningKey" and "isEncryptionKey" are same
     * @return
     */
    public static KeyDescriptorType createKeyDescriptor(Element keyInfo, String algorithm, int keySize, boolean isSigningKey,
            boolean isEncryptionKey) {
        if (keyInfo == null)
            throw logger.nullArgumentError("keyInfo");

        if (isSigningKey == isEncryptionKey)
            throw logger.shouldNotBeTheSameError("Only one of isSigningKey and isEncryptionKey should be true");

        KeyDescriptorType keyDescriptor = new KeyDescriptorType();

        if (isNotNull(algorithm)) {
            EncryptionMethodType encryptionMethod = new EncryptionMethodType(algorithm);

            encryptionMethod.setEncryptionMethod(new EncryptionMethod(BigInteger.valueOf(keySize), null));

            keyDescriptor.addEncryptionMethod(encryptionMethod);
        }

        if (isSigningKey)
            keyDescriptor.setUse(KeyTypes.SIGNING);
        if (isEncryptionKey)
            keyDescriptor.setUse(KeyTypes.ENCRYPTION);

        keyDescriptor.setKeyInfo(keyInfo);

        return keyDescriptor;
    }

    /**
     * Create a key descriptor that specifies an algorithm but does not specify whether the key is for signing or encryption
     *
     * @param keyInfo
     * @param algorithm
     * @param keySize
     * @return
     */
    public static KeyDescriptorType createKeyDescriptor(Element keyInfo, String algorithm, int keySize) {
        if (keyInfo == null)
            throw logger.nullArgumentError("keyInfo");
        KeyDescriptorType keyDescriptor = new KeyDescriptorType();

        if (isNotNull(algorithm)) {
            EncryptionMethodType encryptionMethod = new EncryptionMethodType(algorithm);

            encryptionMethod.setEncryptionMethod(new EncryptionMethod(BigInteger.valueOf(keySize), null));

            keyDescriptor.addEncryptionMethod(encryptionMethod);
        }
        keyDescriptor.setKeyInfo(keyInfo);

        return keyDescriptor;
    }
    
    public static KeyDescriptorType createKeyDescriptor(Element keyDescriptorElement) {
        if (keyDescriptorElement == null)
            throw logger.nullArgumentError("keyDescriptorElement");
        
        KeyDescriptorType keyDescriptor = new KeyDescriptorType();
        
        String use = keyDescriptorElement.getAttribute("use");
        if (use != null && !use.isEmpty()) { 
            keyDescriptor.setUse(KeyTypes.fromValue(use));
        }
        
        Element keyInfoElement = (Element)keyDescriptorElement.getElementsByTagNameNS(JBossSAMLURIConstants.XMLDSIG_NSURI.get(), JBossSAMLConstants.KEY_INFO.get()).item(0);
        keyDescriptor.setKeyInfo(keyInfoElement);
        
        NodeList nl = keyDescriptorElement.getElementsByTagNameNS(JBossSAMLURIConstants.METADATA_NSURI.get(), "EncryptionMethod");
        for (int i = 0; i < nl.getLength(); i++) {
            String algo = ((Element)nl.item(i)).getAttribute("Algorithm");
            keyDescriptor.addEncryptionMethod(new EncryptionMethodType(algo));
        }
        
        return keyDescriptor;
    }
    
}