eu.europa.esig.dss.tsl.sha2.AbstractTrustedListWithSha2Predicate Maven / Gradle / Ivy
/**
* 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.tsl.sha2;
import eu.europa.esig.dss.enumerations.DigestAlgorithm;
import eu.europa.esig.dss.model.DSSDocument;
import eu.europa.esig.dss.model.Digest;
import eu.europa.esig.dss.spi.DSSUtils;
import eu.europa.esig.dss.utils.Utils;
import eu.europa.esig.dss.xml.utils.DomUtils;
import eu.europa.esig.dss.xades.definition.tsl.TrustedListNamespace;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import java.util.Date;
import java.util.function.Predicate;
/**
* This is an abstract implementation of a Predicate for a Trusted List document with sha2 processing,
* containing common utility methods for a Trusted List validation
*
*/
public abstract class AbstractTrustedListWithSha2Predicate implements Predicate {
private static final Logger LOG = LoggerFactory.getLogger(AbstractTrustedListWithSha2Predicate.class);
/** The default sha2 digest algorithm defined in ETSI TS 119 612 */
protected static final DigestAlgorithm SHA2_ALGORITHM = DigestAlgorithm.SHA256;
/** The path to reach a tl:NextUpdate element */
protected static final String NEXT_UPDATE_PATH = "./tl:SchemeInformation/tl:NextUpdate";
static {
DomUtils.registerNamespace(TrustedListNamespace.NS);
}
/**
* Default constructor
*/
protected AbstractTrustedListWithSha2Predicate() {
// empty
}
/**
* This method computes {@code Digest} on the given {@code DSSDocument}'s content
*
* @param document {@link DSSDocument} to compute digest on
* @return {@link Digest}
*/
protected Digest getOriginalDocumentDigest(DSSDocument document) {
if (document == null) {
return null;
}
byte[] digest = document.getDigestValue(SHA2_ALGORITHM);
return new Digest(SHA2_ALGORITHM, digest);
}
/**
* This method parses the {@code sha2Document} and returns the {@code Digest}
*
* @param sha2Document {@link DSSDocument} representing a sha2 document
* @return {@link Digest}
*/
protected Digest getSha2Digest(DSSDocument sha2Document) {
if (sha2Document == null) {
return null;
}
byte[] sha2DocumentBinaries = DSSUtils.toByteArray(sha2Document);
// NOTE: not explicitly defined in the standard, but all known implementations use HEX encoded digest
String sha2DocumentStr = new String(sha2DocumentBinaries);
if (Utils.isHexEncoded(sha2DocumentStr)) {
sha2DocumentBinaries = Utils.fromHex(sha2DocumentStr);
}
return new Digest(SHA2_ALGORITHM, sha2DocumentBinaries);
}
/**
* This method retrieves a NextUpdate date value from the provided Trusted List document
*
* @param tlDocument {@link DSSDocument} representing a cached Trusted List
* @return {@link Date} NextUpdate (when defined)
*/
protected Date getNextUpdate(DSSDocument tlDocument) {
if (!DomUtils.isDOM(tlDocument)) {
LOG.warn("The document is not XML! Unable to extract NextUpdate.");
}
try {
Document documentDom = DomUtils.buildDOM(tlDocument);
Element nextUpdateElement = DomUtils.getElement(documentDom.getDocumentElement(), NEXT_UPDATE_PATH);
if (nextUpdateElement != null) {
String nextUpdate = nextUpdateElement.getTextContent();
if (Utils.isStringNotEmpty(nextUpdate)) {
nextUpdate = Utils.trim(nextUpdate);
return DSSUtils.parseRFCDate(nextUpdate);
} else if (LOG.isDebugEnabled()) {
LOG.debug("NextUpdate element has an empty content.");
}
} else {
LOG.warn("No NextUpdate element found!");
}
} catch (Exception e) {
String errorMessage = "An error occurred on NextUpdate extraction. Reason : {}";
if (LOG.isDebugEnabled()) {
LOG.warn(errorMessage, e.getMessage(), e);
} else {
LOG.warn(errorMessage, e.getMessage());
}
}
return null;
}
}