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/**

 * 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

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

import java.security.KeyFactory;

import java.security.NoSuchAlgorithmException;

import java.security.PublicKey;

import java.security.spec.InvalidKeySpecException;

import java.security.spec.X509EncodedKeySpec;

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

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

import com.sun.org.apache.xml.internal.security.utils.Signature11ElementProxy;

import org.w3c.dom.Document;

import org.w3c.dom.Element;

/**

 * Provides content model support for the {@code dsig11:DEREncodedKeyvalue} element.

 *

 */

public class DEREncodedKeyValue extends Signature11ElementProxy implements KeyInfoContent {

    /** JCA algorithm key types supported by this implementation. */

    private static final String supportedKeyTypes[] = { "RSA", "DSA", "EC"};

    /**

     * Constructor DEREncodedKeyValue

     *

     * @param element

     * @param baseURI

     * @throws XMLSecurityException

     */

    public DEREncodedKeyValue(Element element, String baseURI) throws XMLSecurityException {

        super(element, baseURI);

    }

    /**

     * Constructor DEREncodedKeyValue

     *

     * @param doc

     * @param publicKey

     * @throws XMLSecurityException

     */

    public DEREncodedKeyValue(Document doc, PublicKey publicKey) throws XMLSecurityException {

        super(doc);

        this.addBase64Text(getEncodedDER(publicKey));

    }

    /**

     * Constructor DEREncodedKeyValue

     *

     * @param doc

     * @param encodedKey

     */

    public DEREncodedKeyValue(Document doc, byte[] encodedKey) {

        super(doc);

        this.addBase64Text(encodedKey);

    }

    /**

     * Sets the {@code Id} attribute

     *

     * @param id ID

     */

    public void setId(String id) {

        setLocalIdAttribute(Constants._ATT_ID, id);

    }

    /**

     * Returns the {@code Id} attribute

     *

     * @return the {@code Id} attribute

     */

    public String getId() {

        return getLocalAttribute(Constants._ATT_ID);

    }

    /** {@inheritDoc} */

    public String getBaseLocalName() {

        return Constants._TAG_DERENCODEDKEYVALUE;

    }

    /**

     * Method getPublicKey

     *

     * @return the public key

     * @throws XMLSecurityException

     */

    public PublicKey getPublicKey() throws XMLSecurityException {

        byte[] encodedKey = getBytesFromTextChild();

        // Iterate over the supported key types until one produces a public key.

        for (String keyType : supportedKeyTypes) {

            try {

                KeyFactory keyFactory = KeyFactory.getInstance(keyType);

                X509EncodedKeySpec keySpec = new X509EncodedKeySpec(encodedKey);

                PublicKey publicKey = keyFactory.generatePublic(keySpec);

                if (publicKey != null) {

                    return publicKey;

                }

            } catch (NoSuchAlgorithmException e) { //NOPMD

                // Do nothing, try the next type

            } catch (InvalidKeySpecException e) { //NOPMD

                // Do nothing, try the next type

            }

        }

        throw new XMLSecurityException("DEREncodedKeyValue.UnsupportedEncodedKey");

    }

    /**

     * Method getEncodedDER

     *

     * @return the public key

     * @throws XMLSecurityException

     */

    protected byte[] getEncodedDER(PublicKey publicKey) throws XMLSecurityException {

        try {

            KeyFactory keyFactory = KeyFactory.getInstance(publicKey.getAlgorithm());

            X509EncodedKeySpec keySpec = keyFactory.getKeySpec(publicKey, X509EncodedKeySpec.class);

            return keySpec.getEncoded();

        } catch (NoSuchAlgorithmException e) {

            Object exArgs[] = { publicKey.getAlgorithm(), publicKey.getFormat(), publicKey.getClass().getName() };

            throw new XMLSecurityException(e, "DEREncodedKeyValue.UnsupportedPublicKey", exArgs);

        } catch (InvalidKeySpecException e) {

            Object exArgs[] = { publicKey.getAlgorithm(), publicKey.getFormat(), publicKey.getClass().getName() };

            throw new XMLSecurityException(e, "DEREncodedKeyValue.UnsupportedPublicKey", exArgs);

        }

    }

}