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/*
* Copyright (c) 2005, 2006, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code 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 General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
import java.io.*;
import java.util.*;
import java.security.MessageDigest;
import javax.xml.crypto.*;
import javax.xml.crypto.dsig.*;
import javax.xml.crypto.dsig.dom.DOMValidateContext;
import javax.xml.crypto.dom.*;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.DocumentBuilder;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.Element;
/**
* This is a class which performs xml signature validation upon request
*/
class SignatureValidator {
private File dir;
SignatureValidator(File base) {
dir = base;
}
boolean validate(String fn, KeySelector ks, boolean cache)
throws Exception {
return validate(fn, ks, null, cache);
}
boolean validate(String fn, KeySelector ks, URIDereferencer ud,
boolean cache) throws Exception {
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
dbf.setNamespaceAware(true);
dbf.setValidating(false);
Document doc = dbf.newDocumentBuilder().parse(new File(dir, fn));
NodeList nl =
doc.getElementsByTagNameNS(XMLSignature.XMLNS, "Signature");
if (nl.getLength() == 0) {
throw new Exception("Couldn't find signature Element");
}
Element sigElement = (Element) nl.item(0);
DOMValidateContext vc = new DOMValidateContext(ks, sigElement);
vc.setBaseURI(dir.toURI().toString());
if (cache) {
vc.setProperty("javax.xml.crypto.dsig.cacheReference", Boolean.TRUE);
}
XMLSignatureFactory factory = XMLSignatureFactory.getInstance();
XMLSignature signature = factory.unmarshalXMLSignature(vc);
if (ud != null) {
vc.setURIDereferencer(ud);
}
boolean coreValidity = signature.validate(vc);
// Check reference cache
if (cache) {
Iterator<Reference> i =
signature.getSignedInfo().getReferences().iterator();
for (int j = 0; i.hasNext(); j++) {
Reference ref = i.next();
if (!digestInputEqual(ref)) {
throw new Exception
("cached data for Reference[" + j + "] is not correct");
}
// check that dereferenced data does not contain comment nodes
if (ref.getURI() == "") {
System.out.println("checking deref data");
@SuppressWarnings("unchecked")
NodeSetData<Node> data =
(NodeSetData<Node>)ref.getDereferencedData();
for (Node n : data) {
if (n.getNodeType() == Node.COMMENT_NODE) {
throw new Exception("dereferenced data for " +
" Reference[" + j + " contains comment node");
}
}
}
}
}
return coreValidity;
}
private boolean digestInputEqual(Reference ref) throws Exception {
MessageDigest md = MessageDigest.getInstance("SHA1");
InputStream is = ref.getDigestInputStream();
int nbytes;
byte[] buf = new byte[256];
while ((nbytes = is.read(buf, 0, buf.length)) != -1) {
md.update(buf, 0, nbytes);
}
return Arrays.equals(md.digest(), ref.getDigestValue());
}
}
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