/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.cxf.rs.security.xml;
import java.io.InputStream;
import java.security.PublicKey;
import java.security.cert.X509Certificate;
import javax.ws.rs.core.Response;
import javax.xml.stream.XMLStreamReader;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.apache.cxf.helpers.DOMUtils;
import org.apache.cxf.jaxrs.ext.RequestHandler;
import org.apache.cxf.jaxrs.model.ClassResourceInfo;
import org.apache.cxf.message.Message;
import org.apache.cxf.rs.security.common.CryptoLoader;
import org.apache.cxf.rs.security.common.TrustValidator;
import org.apache.cxf.staxutils.W3CDOMStreamReader;
import org.apache.cxf.ws.security.SecurityConstants;
import org.apache.ws.security.components.crypto.Crypto;
import org.apache.xml.security.exceptions.XMLSecurityException;
import org.apache.xml.security.keys.KeyInfo;
import org.apache.xml.security.signature.Reference;
import org.apache.xml.security.signature.XMLSignature;
import org.apache.xml.security.transforms.Transform;
import org.apache.xml.security.transforms.Transforms;
import org.apache.xml.security.utils.Constants;
public class XmlSigInHandler extends AbstractXmlSecInHandler implements RequestHandler {
private boolean removeSignature = true;
private boolean persistSignature = true;
public void setRemoveSignature(boolean remove) {
this.removeSignature = remove;
}
public void setPersistSignature(boolean persist) {
this.persistSignature = persist;
}
public Response handleRequest(Message message, ClassResourceInfo resourceClass) {
Document doc = getDocument(message);
if (doc == null) {
return null;
}
Element root = doc.getDocumentElement();
Element signatureElement = getSignatureElement(root);
if (signatureElement == null) {
throwFault("XML Signature is not available", null);
}
Crypto crypto = null;
try {
CryptoLoader loader = new CryptoLoader();
crypto = loader.getCrypto(message,
SecurityConstants.SIGNATURE_CRYPTO,
SecurityConstants.SIGNATURE_PROPERTIES);
if (crypto == null) {
crypto = loader.getCrypto(message,
SecurityConstants.ENCRYPT_CRYPTO,
SecurityConstants.ENCRYPT_PROPERTIES);
}
} catch (Exception ex) {
throwFault("Crypto can not be loaded", ex);
}
boolean valid = false;
Reference ref = null;
try {
XMLSignature signature = new XMLSignature(signatureElement, "");
// See also WSS4J SAMLUtil.getCredentialFromKeyInfo
KeyInfo keyInfo = signature.getKeyInfo();
X509Certificate cert = keyInfo.getX509Certificate();
if (cert != null) {
valid = signature.checkSignatureValue(cert);
} else {
PublicKey pk = keyInfo.getPublicKey();
if (pk != null) {
valid = signature.checkSignatureValue(pk);
}
}
// is this call redundant given that signature.checkSignatureValue uses References ?
ref = getReference(signature);
Element signedElement = validateReference(root, ref);
// validate trust
new TrustValidator().validateTrust(crypto, cert, keyInfo.getPublicKey());
if (persistSignature) {
message.setContent(XMLSignature.class, signature);
message.setContent(Element.class, signedElement);
}
} catch (Exception ex) {
throwFault("Signature validation failed", ex);
}
if (!valid) {
throwFault("Signature validation failed", null);
}
if (removeSignature) {
if (!isEnveloping(root)) {
Element signedEl = getSignedElement(root, ref);
signedEl.removeAttribute("ID");
root.removeChild(signatureElement);
} else {
Element actualBody = getActualBody(root);
Document newDoc = DOMUtils.createDocument();
newDoc.adoptNode(actualBody);
root = actualBody;
}
}
message.setContent(XMLStreamReader.class,
new W3CDOMStreamReader(root));
message.setContent(InputStream.class, null);
//TODO: If we have a SAML assertion header as well with holder-of-key or
// sender-vouches claims then we will need to store signature or parts of it
// to validate that saml assertion and this payload have been signed by the
// same key
return null;
}
private Element getActualBody(Element envelopingSigElement) {
Element objectNode = getNode(envelopingSigElement, Constants.SignatureSpecNS, "Object", 0);
if (objectNode == null) {
throwFault("Object envelope is not available", null);
}
Element node = DOMUtils.getFirstElement(objectNode);
if (node == null) {
throwFault("No signed data is found", null);
}
return node;
}
private Element getSignatureElement(Element sigParentElement) {
if (isEnveloping(sigParentElement)) {
return sigParentElement;
}
return DOMUtils.getFirstChildWithName(sigParentElement, Constants.SignatureSpecNS, "Signature");
}
protected boolean isEnveloping(Element root) {
return Constants.SignatureSpecNS.equals(root.getNamespaceURI())
&& "Signature".equals(root.getLocalName());
}
protected Reference getReference(XMLSignature sig) {
int count = sig.getSignedInfo().getLength();
if (count != 1) {
throwFault("Multiple Signature Reference are not currently supported", null);
}
try {
return sig.getSignedInfo().item(0);
} catch (XMLSecurityException ex) {
throwFault("Signature Reference is not available", ex);
}
return null;
}
protected Element validateReference(Element root, Reference ref) {
boolean enveloped = false;
String refId = ref.getURI();
if (!refId.startsWith("#") || refId.length() <= 1) {
throwFault("Only local Signature References are supported", null);
}
Element signedEl = getSignedElement(root, ref);
if (signedEl != null) {
enveloped = signedEl == root;
} else {
throwFault("Signature Reference ID is invalid", null);
}
Transforms transforms = null;
try {
transforms = ref.getTransforms();
} catch (XMLSecurityException ex) {
throwFault("Signature transforms can not be obtained", ex);
}
if (enveloped) {
boolean isEnveloped = false;
for (int i = 0; i < transforms.getLength(); i++) {
try {
Transform tr = transforms.item(i);
if (Transforms.TRANSFORM_ENVELOPED_SIGNATURE.equals(tr.getURI())) {
isEnveloped = true;
break;
}
} catch (Exception ex) {
throwFault("Problem accessing Transform instance", ex);
}
}
if (!isEnveloped) {
throwFault("Only enveloped signatures are currently supported", null);
}
}
return signedEl;
}
private Element getSignedElement(Element root, Reference ref) {
String rootId = root.getAttribute("ID");
String expectedID = ref.getURI().substring(1);
if (!expectedID.equals(rootId)) {
return (Element)DOMUtils.findChildWithAtt(root, null, "ID", expectedID);
} else {
return root;
}
}
}