/**
* 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.List;
import org.w3c.dom.Element;
import eu.europa.esig.dss.DSSException;
import eu.europa.esig.dss.DomUtils;
import eu.europa.esig.dss.SignatureLevel;
import eu.europa.esig.dss.XAdESNamespaces;
import eu.europa.esig.dss.utils.Utils;
import eu.europa.esig.dss.validation.CertificateVerifier;
import eu.europa.esig.dss.validation.DefaultAdvancedSignature;
import eu.europa.esig.dss.validation.SignatureCryptographicVerification;
import eu.europa.esig.dss.validation.ValidationContext;
import eu.europa.esig.dss.x509.CertificateToken;
import eu.europa.esig.dss.x509.RevocationToken;
import eu.europa.esig.dss.x509.crl.CRLToken;
import eu.europa.esig.dss.x509.ocsp.OCSPToken;
/**
* LT profile of XAdES signature
*
*/
public class XAdESLevelBaselineLT extends XAdESLevelBaselineT {
/**
* The default constructor for XAdESLevelBaselineLT.
*/
public XAdESLevelBaselineLT(final CertificateVerifier certificateVerifier) {
super(certificateVerifier);
}
/**
* Adds <CertificateValues> and <RevocationValues> segments to <UnsignedSignatureProperties>.<br>
* An XML electronic signature MAY contain at most one:<br>
* - CertificateValues element and<br>
* - RevocationValues element.
*
* @see XAdESLevelX#extendSignatureTag()
*/
@Override
protected void extendSignatureTag() throws DSSException {
assertExtendSignaturePossible();
super.extendSignatureTag();
if (xadesSignature.hasLTAProfile()) {
return;
}
/**
* In all cases the -LT level need to be regenerated.
*/
checkSignatureIntegrity();
final ValidationContext valContext = xadesSignature.getSignatureValidationContext(certificateVerifier);
removeOldCertificateValues();
removeOldRevocationValues();
final List<CertificateToken> toIncludeCertificates = getToIncludeCertificateTokens(valContext);
incorporateCertificateValues(unsignedSignaturePropertiesDom, toIncludeCertificates);
incorporateRevocationValues(unsignedSignaturePropertiesDom, valContext);
/**
* Certificate(s), revocation data where added, XAdES signature certificate source must be reset.
*/
xadesSignature.resetCertificateSource();
xadesSignature.resetRevocationSources();
}
/**
* This method checks the signature integrity and throws a {@code DSSException} if the signature is broken.
*
* @throws eu.europa.esig.dss.DSSException
*/
protected void checkSignatureIntegrity() throws DSSException {
final SignatureCryptographicVerification signatureCryptographicVerification = xadesSignature.getSignatureCryptographicVerification();
if (!signatureCryptographicVerification.isSignatureIntact()) {
final String errorMessage = signatureCryptographicVerification.getErrorMessage();
throw new DSSException("Cryptographic signature verification has failed" + (errorMessage.isEmpty() ? "." : (" / " + errorMessage)));
}
}
/**
* This method removes old revocation values from the unsigned signature properties element.
*/
private void removeOldRevocationValues() {
final Element toRemove = xadesSignature.getRevocationValues();
if (toRemove != null) {
unsignedSignaturePropertiesDom.removeChild(toRemove);
xadesSignature.resetRevocationSources();
}
}
/**
* This method removes old certificates values from the unsigned signature properties element.
*/
private void removeOldCertificateValues() {
final Element toRemove = xadesSignature.getCertificateValues();
if (toRemove != null) {
unsignedSignaturePropertiesDom.removeChild(toRemove);
xadesSignature.resetCertificateSource();
}
}
/**
* This method incorporates revocation values.
*
* @param parentDom
* @param validationContext
*/
protected void incorporateRevocationValues(final Element parentDom, final ValidationContext validationContext) {
// <xades:RevocationValues>
final DefaultAdvancedSignature.RevocationDataForInclusion revocationsForInclusion = xadesSignature.getRevocationDataForInclusion(validationContext);
if (!revocationsForInclusion.isEmpty()) {
final Element revocationValuesDom = DomUtils.addElement(documentDom, parentDom, XAdESNamespaces.XAdES, "xades:RevocationValues");
incorporateCrlTokens(revocationValuesDom, revocationsForInclusion.crlTokens);
incorporateOcspTokens(revocationValuesDom, revocationsForInclusion.ocspTokens);
}
}
private void incorporateCrlTokens(final Element parentDom, final List<CRLToken> crlTokens) {
if (crlTokens.isEmpty()) {
return;
}
// ...<xades:CRLValues/>
final Element crlValuesDom = DomUtils.addElement(documentDom, parentDom, XAdESNamespaces.XAdES, "xades:CRLValues");
for (final RevocationToken revocationToken : crlTokens) {
final byte[] encodedCRL = revocationToken.getEncoded();
final String base64EncodedCRL = Utils.toBase64(encodedCRL);
DomUtils.addTextElement(documentDom, crlValuesDom, XAdESNamespaces.XAdES, "xades:EncapsulatedCRLValue", base64EncodedCRL);
}
}
private void incorporateOcspTokens(Element parentDom, final List<OCSPToken> ocspTokens) {
if (ocspTokens.isEmpty()) {
return;
}
// ...<xades:OCSPValues>
// .........<xades:EncapsulatedOCSPValue>MIIERw...
final Element ocspValuesDom = DomUtils.addElement(documentDom, parentDom, XAdESNamespaces.XAdES, "xades:OCSPValues");
for (final RevocationToken revocationToken : ocspTokens) {
final byte[] encodedOCSP = revocationToken.getEncoded();
final String base64EncodedOCSP = Utils.toBase64(encodedOCSP);
DomUtils.addTextElement(documentDom, ocspValuesDom, XAdESNamespaces.XAdES, "xades:EncapsulatedOCSPValue", base64EncodedOCSP);
}
}
/**
* Checks if the extension is possible.
*/
private void assertExtendSignaturePossible() throws DSSException {
final SignatureLevel signatureLevel = params.getSignatureLevel();
if (SignatureLevel.XAdES_BASELINE_LT.equals(signatureLevel) && xadesSignature.hasLTAProfile()) {
final String exceptionMessage = "Cannot extend signature. The signedData is already extended with [%s].";
throw new DSSException(String.format(exceptionMessage, "XAdES LTA"));
}
}
}