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 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/**

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements. See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership. The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License. You may obtain a copy of the License at

 *

 * http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing,

 * software distributed under the License is distributed on an

 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

 * KIND, either express or implied. See the License for the

 * specific language governing permissions and limitations

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package com.sun.org.apache.xml.internal.security.keys.keyresolver.implementations;

import java.security.PublicKey;

import java.security.cert.X509Certificate;

import com.sun.org.apache.xml.internal.security.exceptions.XMLSecurityException;

import com.sun.org.apache.xml.internal.security.keys.content.keyvalues.DSAKeyValue;

import com.sun.org.apache.xml.internal.security.keys.keyresolver.KeyResolverSpi;

import com.sun.org.apache.xml.internal.security.keys.storage.StorageResolver;

import com.sun.org.apache.xml.internal.security.utils.Constants;

import com.sun.org.apache.xml.internal.security.utils.XMLUtils;

import org.w3c.dom.Element;

public class DSAKeyValueResolver extends KeyResolverSpi {

    private static final com.sun.org.slf4j.internal.Logger LOG =

        com.sun.org.slf4j.internal.LoggerFactory.getLogger(DSAKeyValueResolver.class);

    /**

     * Method engineResolvePublicKey

     *

     * @param element

     * @param baseURI

     * @param storage

     * @return null if no {@link PublicKey} could be obtained

     */

    public PublicKey engineLookupAndResolvePublicKey(

        Element element, String baseURI, StorageResolver storage

    ) {

        if (element == null) {

            return null;

        }

        Element dsaKeyElement = null;

        boolean isKeyValue =

            XMLUtils.elementIsInSignatureSpace(element, Constants._TAG_KEYVALUE);

        if (isKeyValue) {

            dsaKeyElement =

                XMLUtils.selectDsNode(element.getFirstChild(), Constants._TAG_DSAKEYVALUE, 0);

        } else if (XMLUtils.elementIsInSignatureSpace(element, Constants._TAG_DSAKEYVALUE)) {

            // this trick is needed to allow the RetrievalMethodResolver to eat a

            // ds:DSAKeyValue directly (without KeyValue)

            dsaKeyElement = element;

        }

        if (dsaKeyElement == null) {

            return null;

        }

        try {

            DSAKeyValue dsaKeyValue = new DSAKeyValue(dsaKeyElement, baseURI);

            PublicKey pk = dsaKeyValue.getPublicKey();

            return pk;

        } catch (XMLSecurityException ex) {

            LOG.debug(ex.getMessage(), ex);

            //do nothing

        }

        return null;

    }

    /** {@inheritDoc} */

    public X509Certificate engineLookupResolveX509Certificate(

        Element element, String baseURI, StorageResolver storage

    ) {

        return null;

    }

    /** {@inheritDoc} */

    public javax.crypto.SecretKey engineLookupAndResolveSecretKey(

        Element element, String baseURI, StorageResolver storage

    ) {

        return null;

    }

}