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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

 * under the License.

 */

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

import java.io.ByteArrayInputStream;

import java.io.IOException;

import java.io.InputStream;

import java.security.PrivateKey;

import java.security.PublicKey;

import java.security.cert.X509Certificate;

import javax.crypto.SecretKey;

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

import com.sun.org.apache.xml.internal.security.parser.XMLParserException;

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

import org.w3c.dom.Document;

import org.w3c.dom.Element;

/**

 * This class is an abstract class to resolve a Key of some kind given a KeyInfo element.

 *

 * If you want the your KeyResolver, at firstly you must extend this class, and register

 * as following in config.xml

 * <PRE>

 *  <KeyResolver URI="http://www.w3.org/2000/09/xmldsig#KeyValue"

 *   JAVACLASS="MyPackage.MyKeyValueImpl"//gt;

 * </PRE>

 *

 * Extensions of this class must be thread-safe.

 */

public abstract class KeyResolverSpi {

    /**

     * This method returns whether the KeyResolverSpi is able to perform the requested action.

     *

     * @param element

     * @param baseURI

     * @param storage

     * @return whether the KeyResolverSpi is able to perform the requested action.

     */

    protected abstract boolean engineCanResolve(Element element, String baseURI, StorageResolver storage);

    /**

     * Method engineResolvePublicKey

     *

     * @param element

     * @param baseURI

     * @param storage

     * @param secureValidation

     * @return resolved public key from the registered from the element.

     *

     * @throws KeyResolverException

     */

    protected abstract PublicKey engineResolvePublicKey(

        Element element, String baseURI, StorageResolver storage, boolean secureValidation

    ) throws KeyResolverException;

    /**

     * Method engineLookupAndResolvePublicKey

     *

     * @param element

     * @param baseURI

     * @param storage

     * @param secureValidation

     * @return resolved public key from the registered from the element.

     *

     * @throws KeyResolverException

     */

    public PublicKey engineLookupAndResolvePublicKey(

        Element element, String baseURI, StorageResolver storage, boolean secureValidation

    ) throws KeyResolverException {

        if (!engineCanResolve(element, baseURI, storage)) {

            return null;

        }

        return engineResolvePublicKey(element, baseURI, storage, secureValidation);

    }

    /**

     * Method engineResolveCertificate

     *

     * @param element

     * @param baseURI

     * @param storage

     * @param secureValidation

     * @return resolved X509Certificate key from the registered from the elements

     *

     * @throws KeyResolverException

     */

    protected abstract X509Certificate engineResolveX509Certificate(

        Element element, String baseURI, StorageResolver storage, boolean secureValidation

    ) throws KeyResolverException;

    /**

     * Method engineLookupResolveX509Certificate

     *

     * @param element

     * @param baseURI

     * @param storage

     * @param secureValidation

     * @return resolved X509Certificate key from the registered from the elements

     *

     * @throws KeyResolverException

     */

    public X509Certificate engineLookupResolveX509Certificate(

        Element element, String baseURI, StorageResolver storage, boolean secureValidation

    ) throws KeyResolverException {

        if (!engineCanResolve(element, baseURI, storage)) {

            return null;

        }

        return engineResolveX509Certificate(element, baseURI, storage, secureValidation);

    }

    /**

     * Method engineResolveSecretKey

     *

     * @param element

     * @param baseURI

     * @param storage

     * @param secureValidation

     * @return resolved SecretKey key from the registered from the elements

     *

     * @throws KeyResolverException

     */

    protected abstract SecretKey engineResolveSecretKey(

        Element element, String baseURI, StorageResolver storage, boolean secureValidation

    ) throws KeyResolverException;

    /**

     * Method engineLookupAndResolveSecretKey

     *

     * @param element

     * @param baseURI

     * @param storage

     * @param secureValidation

     * @return resolved SecretKey key from the registered from the elements

     *

     * @throws KeyResolverException

     */

    public SecretKey engineLookupAndResolveSecretKey(

        Element element, String baseURI, StorageResolver storage, boolean secureValidation

    ) throws KeyResolverException {

        if (!engineCanResolve(element, baseURI, storage)) {

            return null;

        }

        return engineResolveSecretKey(element, baseURI, storage, secureValidation);

    }

    /**

     * Method engineResolvePrivateKey

     *

     * @param element

     * @param baseURI

     * @param storage

     * @param secureValidation

     * @return resolved PrivateKey key from the registered from the elements

     *

     * @throws KeyResolverException

     */

    protected abstract PrivateKey engineResolvePrivateKey(

        Element element, String baseURI, StorageResolver storage, boolean secureValidation

    ) throws KeyResolverException;

    /**

     * Method engineLookupAndResolvePrivateKey

     *

     * @param element

     * @param baseURI

     * @param storage

     * @param secureValidation

     * @return resolved PrivateKey key from the registered from the elements

     *

     * @throws KeyResolverException

     */

    public PrivateKey engineLookupAndResolvePrivateKey(

        Element element, String baseURI, StorageResolver storage, boolean secureValidation

    ) throws KeyResolverException {

        if (!engineCanResolve(element, baseURI, storage)) {

            return null;

        }

        return engineResolvePrivateKey(element, baseURI, storage, secureValidation);

    }

    /**

     * Parses a byte array and returns the parsed Element.

     *

     * @param bytes

     * @return the Document Element after parsing bytes

     * @throws KeyResolverException if something goes wrong

     */

    protected static Element getDocFromBytes(byte[] bytes, boolean secureValidation) throws KeyResolverException {

        try (InputStream is = new ByteArrayInputStream(bytes)) {

            Document doc = XMLUtils.read(is, secureValidation);

            return doc.getDocumentElement();

        } catch (XMLParserException ex) {

            throw new KeyResolverException(ex);

        } catch (IOException ex) {

            throw new KeyResolverException(ex);

        }

    }

}