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

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Here is the source code for eu.europa.esig.dss.xades.signature.CounterSignatureBuilder.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 static eu.europa.esig.dss.XAdESNamespaces.XAdES;

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

import javax.xml.crypto.dsig.CanonicalizationMethod;

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

import eu.europa.esig.dss.DSSDocument;
import eu.europa.esig.dss.DSSXMLUtils;
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;
import eu.europa.esig.dss.xades.validation.XAdESSignature;

/**
 * This class provides the methods required to countersign a given signature and extend the existing signature with the generated
 * countersignature.
 */
public class CounterSignatureBuilder extends EnvelopedSignatureBuilder {

    private XAdESSignature toCounterSignXadesSignature;

    public CounterSignatureBuilder(final DSSDocument toCounterSignDocument,
            final XAdESSignature toCounterSignXadesSignature, final XAdESSignatureParameters parameters,
            final CertificateVerifier certificateVerifier) {

        super(parameters, toCounterSignDocument, certificateVerifier);
        this.toCounterSignXadesSignature = toCounterSignXadesSignature;
    }

    @Override
    protected List<DSSReference> createDefaultReferences() {

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

        final DSSReference dssReference = new DSSReference();
        dssReference.setId("cs-r-id-1");
        dssReference.setUri("#" + params.getToCounterSignSignatureValueId());
        dssReference.setType(xPathQueryHolder.XADES_COUNTERSIGNED_SIGNATURE);
        dssReference.setContents(detachedDocument);
        dssReference.setDigestMethodAlgorithm(params.getDigestAlgorithm());

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

        DSSTransform dssTransform = new DSSTransform();
        dssTransform.setAlgorithm(CanonicalizationMethod.EXCLUSIVE);
        dssTransform.setPerform(true);
        dssTransformList.add(dssTransform);

        dssReference.setTransforms(dssTransformList);

        references.add(dssReference);

        return references;
    }

    @Override
    protected Document buildRootDocumentDom() {
        return DSSXMLUtils.buildDOM();
    }

    @Override
    protected Node getParentNodeOfSignature() {
        return documentDom;
    }

    /**
     * This method incorporates a given countersignature value in the current signature XML DOM.
     *
     * @param counterSignatureValue
     * @return
     */
    @Override
    public DSSDocument signDocument(final byte[] counterSignatureValue) {

        if (!built) {
            build();
        }

        unsignedSignaturePropertiesDom = toCounterSignXadesSignature.getUnsignedSignaturePropertiesDom();
        final Document ownerDocument = toCounterSignXadesSignature.getSignatureElement().getOwnerDocument();
        if (unsignedSignaturePropertiesDom == null) {

            Element unsignedPropertiesDom = toCounterSignXadesSignature.getUnsignedPropertiesDom();
            if (unsignedPropertiesDom == null) {

                final Element qualifyingPropertiesDom = toCounterSignXadesSignature.getQualifyingPropertiesDom();
                // TODO-Vin (15/09/2014): add null check
                unsignedPropertiesDom = DSSXMLUtils.addElement(ownerDocument, qualifyingPropertiesDom, XAdES,
                        XADES_UNSIGNED_PROPERTIES);
            }
            unsignedSignaturePropertiesDom = DSSXMLUtils.addElement(ownerDocument, unsignedPropertiesDom, XAdES,
                    XADES_UNSIGNED_SIGNATURE_PROPERTIES);
        }

        final Element counterSignatureElement = DSSXMLUtils.addElement(ownerDocument,
                unsignedSignaturePropertiesDom, XAdES, XADES_COUNTER_SIGNATURE);
        final String signatureValueBase64Encoded = Base64.encodeBase64String(counterSignatureValue);
        final Text signatureValueNode = documentDom.createTextNode(signatureValueBase64Encoded);
        signatureValueDom.appendChild(signatureValueNode);

        final Node importedNode = ownerDocument.importNode(documentDom.getFirstChild(), true);
        counterSignatureElement.appendChild(importedNode);

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