eu.europa.esig.dss.xades.signature.EnvelopingSignatureBuilder.java Source code

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Here is the source code for eu.europa.esig.dss.xades.signature.EnvelopingSignatureBuilder.java

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/**
 * DSS - Digital Signature Services
 * Copyright (C) 2015 European Commission, provided under the CEF programme
 *
 * This file is part of the "DSS - Digital Signature Services" project.
 *
 * This library 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 library 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 library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */
package eu.europa.esig.dss.xades.signature;

import java.util.ArrayList;
import java.util.List;

import javax.xml.crypto.dsig.CanonicalizationMethod;
import javax.xml.crypto.dsig.XMLSignature;

import org.apache.commons.codec.binary.Base64;
import org.w3c.dom.Element;
import org.w3c.dom.Text;

import eu.europa.esig.dss.DSSDocument;
import eu.europa.esig.dss.DSSException;
import eu.europa.esig.dss.DSSXMLUtils;
import eu.europa.esig.dss.EncryptionAlgorithm;
import eu.europa.esig.dss.InMemoryDocument;
import eu.europa.esig.dss.MimeType;
import eu.europa.esig.dss.validation.CertificateVerifier;
import eu.europa.esig.dss.xades.DSSReference;
import eu.europa.esig.dss.xades.DSSTransform;
import eu.europa.esig.dss.xades.XAdESSignatureParameters;

/**
 * This class handles the specifics of the enveloping XML signature
 *
 */
class EnvelopingSignatureBuilder extends XAdESSignatureBuilder {

    /**
     * The default constructor for EnvelopingSignatureBuilder. The enveloped signature uses by default the inclusive
     * method of canonicalization.
     *  @param params  The set of parameters relating to the structure and process of the creation or extension of the
     *                electronic signature.
     * @param origDoc The original document to sign.
     * @param certificateVerifier
     */
    public EnvelopingSignatureBuilder(final XAdESSignatureParameters params, final DSSDocument origDoc,
            final CertificateVerifier certificateVerifier) {

        super(params, origDoc, certificateVerifier);
        setCanonicalizationMethods(params, CanonicalizationMethod.INCLUSIVE);
    }

    /**
     * This method creates the first reference (this is a reference to the file to sign) witch is specific for each form
     * of signature. Here, the value of the URI is an unique identifier to the base64 encoded data (file). The data are
     * included in the signature XML.
     *
     * @throws DSSException
     */
    @Override
    protected void incorporateReferences() throws DSSException {

        final List<DSSReference> references = params.getReferences();
        for (final DSSReference reference : references) {

            incorporateReference(reference);
        }
    }

    @Override
    protected List<DSSReference> createDefaultReferences() {

        final List<DSSReference> references = new ArrayList<DSSReference>();

        //<ds:Reference Id="signed-data-ref" Type="http://www.w3.org/2000/09/xmldsig#Object" URI="#signed-data-idfc5ff27ee49763d9ba88ba5bbc49f732">
        final DSSReference reference = new DSSReference();
        reference.setId("r-id-1");
        reference.setType(HTTP_WWW_W3_ORG_2000_09_XMLDSIG_OBJECT);
        reference.setUri("#o-id-1");
        reference.setContents(detachedDocument);
        reference.setDigestMethodAlgorithm(params.getDigestAlgorithm());

        final List<DSSTransform> transforms = new ArrayList<DSSTransform>();

        final DSSTransform transform = new DSSTransform();
        transform.setAlgorithm(CanonicalizationMethod.BASE64);

        transforms.add(transform);
        reference.setTransforms(transforms);
        references.add(reference);

        return references;
    }

    @Override
    protected DSSDocument transformReference(final DSSReference reference) {

        return reference.getContents();
    }

    /**
     * Adds signature value to the signature and returns XML signature (InMemoryDocument)
     *
     * @param signatureValue
     * @return
     * @throws DSSException
     */
    @Override
    public DSSDocument signDocument(final byte[] signatureValue) throws DSSException {
        if (!built) {
            build();
        }

        final EncryptionAlgorithm encryptionAlgorithm = params.getEncryptionAlgorithm();
        final byte[] signatureValueBytes = DSSSignatureUtils.convertToXmlDSig(encryptionAlgorithm, signatureValue);
        final String signatureValueBase64Encoded = Base64.encodeBase64String(signatureValueBytes);
        final Text signatureValueNode = documentDom.createTextNode(signatureValueBase64Encoded);
        signatureValueDom.appendChild(signatureValueNode);

        final List<DSSReference> references = params.getReferences();
        for (final DSSReference reference : references) {

            // <ds:Object>
            final String base64EncodedOriginalDocument = reference.getContents().getBase64Encoded();
            final Element objectDom = DSSXMLUtils.addTextElement(documentDom, signatureDom, XMLSignature.XMLNS,
                    DS_OBJECT, base64EncodedOriginalDocument);
            final String id = reference.getUri().substring(1);
            objectDom.setAttribute(ID, id);
        }

        byte[] documentBytes = DSSXMLUtils.transformDomToByteArray(documentDom);
        final InMemoryDocument inMemoryDocument = new InMemoryDocument(documentBytes);
        inMemoryDocument.setMimeType(MimeType.XML);
        return inMemoryDocument;
    }
}