/**
* 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.ByteArrayInputStream;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.security.PrivateKey;
import java.security.cert.X509Certificate;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.security.auth.callback.CallbackHandler;
import javax.xml.stream.XMLStreamReader;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.apache.cxf.common.util.Base64Exception;
import org.apache.cxf.common.util.Base64Utility;
import org.apache.cxf.helpers.DOMUtils;
import org.apache.cxf.message.Message;
import org.apache.cxf.rs.security.common.CryptoLoader;
import org.apache.cxf.rs.security.common.SecurityUtils;
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.WSConstants;
import org.apache.ws.security.WSSecurityException;
import org.apache.ws.security.components.crypto.Crypto;
import org.apache.ws.security.util.WSSecurityUtil;
import org.apache.xml.security.encryption.XMLCipher;
import org.apache.xml.security.encryption.XMLEncryptionException;
import org.apache.xml.security.utils.Constants;
public abstract class AbstractXmlEncInHandler extends AbstractXmlSecInHandler {
private EncryptionProperties encProps;
public void decryptContent(Message message) {
Message outMs = message.getExchange().getOutMessage();
Message inMsg = outMs == null ? message : outMs.getExchange().getInMessage();
Document doc = getDocument(inMsg);
if (doc == null) {
return;
}
Element root = doc.getDocumentElement();
byte[] symmetricKeyBytes = getSymmetricKeyBytes(message, root);
String symKeyAlgo = getEncodingMethodAlgorithm(root);
if (encProps != null && encProps.getEncryptionSymmetricKeyAlgo() != null
&& !encProps.getEncryptionSymmetricKeyAlgo().equals(symKeyAlgo)) {
throwFault("Encryption Symmetric Key Algorithm is not supported", null);
}
byte[] decryptedPayload = null;
try {
decryptedPayload = decryptPayload(root, symmetricKeyBytes, symKeyAlgo);
} catch (Exception ex) {
throwFault("Payload can not be decrypted", ex);
}
Document payloadDoc = null;
try {
payloadDoc = DOMUtils.readXml(new InputStreamReader(new ByteArrayInputStream(decryptedPayload),
"UTF-8"));
} catch (Exception ex) {
throwFault("Payload document can not be created", ex);
}
message.setContent(XMLStreamReader.class,
new W3CDOMStreamReader(payloadDoc));
message.setContent(InputStream.class, null);
}
// Subclasses can overwrite it and return the bytes, assuming they know the actual key
protected byte[] getSymmetricKeyBytes(Message message, Element encDataElement) {
String cryptoKey = null;
String propKey = null;
if (SecurityUtils.isSignedAndEncryptedTwoWay(message)) {
cryptoKey = SecurityConstants.SIGNATURE_CRYPTO;
propKey = SecurityConstants.SIGNATURE_PROPERTIES;
} else {
cryptoKey = SecurityConstants.ENCRYPT_CRYPTO;
propKey = SecurityConstants.ENCRYPT_PROPERTIES;
}
Crypto crypto = null;
try {
crypto = new CryptoLoader().getCrypto(message, cryptoKey, propKey);
} catch (Exception ex) {
throwFault("Crypto can not be loaded", ex);
}
Element encKeyElement = getNode(encDataElement, WSConstants.ENC_NS, "EncryptedKey", 0);
if (encKeyElement == null) {
//TODO: support EncryptedData/ds:KeyInfo - the encrypted key is passed out of band
throwFault("EncryptedKey element is not available", null);
}
X509Certificate cert = loadCertificate(crypto, encKeyElement);
try {
new TrustValidator().validateTrust(crypto, cert, null);
} catch (Exception ex) {
throwFault(ex.getMessage(), ex);
}
// now start decrypting
String keyEncAlgo = getEncodingMethodAlgorithm(encKeyElement);
String digestAlgo = getDigestMethodAlgorithm(encKeyElement);
if (encProps != null) {
if (encProps.getEncryptionKeyTransportAlgo() != null
&& !encProps.getEncryptionKeyTransportAlgo().equals(keyEncAlgo)) {
throwFault("Key Transport Algorithm is not supported", null);
}
if (encProps.getEncryptionDigestAlgo() != null
&& (digestAlgo == null || !encProps.getEncryptionDigestAlgo().equals(digestAlgo))) {
throwFault("Digest Algorithm is not supported", null);
}
} else if (!XMLCipher.RSA_OAEP.equals(keyEncAlgo)) {
// RSA OAEP is the required default Key Transport Algorithm
throwFault("Key Transport Algorithm is not supported", null);
}
Element cipherValue = getNode(encKeyElement, WSConstants.ENC_NS,
"CipherValue", 0);
if (cipherValue == null) {
throwFault("CipherValue element is not available", null);
}
try {
return decryptSymmetricKey(cipherValue.getTextContent().trim(),
cert,
crypto,
keyEncAlgo,
digestAlgo,
message);
} catch (Exception ex) {
throwFault(ex.getMessage(), ex);
}
return null;
}
private X509Certificate loadCertificate(Crypto crypto, Element encKeyElement) {
/**
* TODO: the following can be easily supported too
<X509SKI>31d97bd7</X509SKI>
<X509SubjectName>Subject of Certificate B</X509SubjectName>
*
*/
String keyIdentifierType = encProps != null ? encProps.getEncryptionKeyIdType() : null;
if (keyIdentifierType == null || keyIdentifierType.equals(SecurityUtils.X509_CERT)) {
Element certNode = getNode(encKeyElement,
Constants.SignatureSpecNS, "X509Certificate", 0);
if (certNode != null) {
try {
return SecurityUtils.loadX509Certificate(crypto, certNode);
} catch (Exception ex) {
throwFault("X509Certificate can not be created", ex);
}
}
}
if (keyIdentifierType == null || keyIdentifierType.equals(SecurityUtils.X509_ISSUER_SERIAL)) {
Element certNode = getNode(encKeyElement,
Constants.SignatureSpecNS, "X509IssuerSerial", 0);
if (certNode != null) {
try {
return SecurityUtils.loadX509IssuerSerial(crypto, certNode);
} catch (Exception ex) {
throwFault("X509Certificate can not be created", ex);
}
}
}
throwFault("Certificate is missing", null);
return null;
}
private String getEncodingMethodAlgorithm(Element parent) {
Element encMethod = getNode(parent, WSConstants.ENC_NS, "EncryptionMethod", 0);
if (encMethod == null) {
throwFault("EncryptionMethod element is not available", null);
}
return encMethod.getAttribute("Algorithm");
}
private String getDigestMethodAlgorithm(Element parent) {
Element encMethod = getNode(parent, WSConstants.ENC_NS, "EncryptionMethod", 0);
if (encMethod != null) {
Element digestMethod = getNode(encMethod, WSConstants.SIG_NS, "DigestMethod", 0);
if (digestMethod != null) {
return digestMethod.getAttributeNS(null, "Algorithm");
}
}
return null;
}
//TODO: Support symmetric keys if requested
protected byte[] decryptSymmetricKey(String base64EncodedKey,
X509Certificate cert,
Crypto crypto,
String keyEncAlgo,
Message message) throws WSSecurityException {
return decryptSymmetricKey(base64EncodedKey, cert, crypto, keyEncAlgo, null, message);
}
//TODO: Support symmetric keys if requested
protected byte[] decryptSymmetricKey(String base64EncodedKey,
X509Certificate cert,
Crypto crypto,
String keyEncAlgo,
String digestAlgo,
Message message) throws WSSecurityException {
CallbackHandler callback = SecurityUtils.getCallbackHandler(message, this.getClass());
PrivateKey key = null;
try {
key = crypto.getPrivateKey(cert, callback);
} catch (Exception ex) {
throwFault("Encrypted key can not be decrypted", ex);
}
Cipher cipher =
EncryptionUtils.initCipherWithKey(keyEncAlgo, digestAlgo, Cipher.DECRYPT_MODE, key);
try {
byte[] encryptedBytes = Base64Utility.decode(base64EncodedKey);
return cipher.doFinal(encryptedBytes);
} catch (Base64Exception ex) {
throwFault("Base64 decoding has failed", ex);
} catch (Exception ex) {
throwFault("Encrypted key can not be decrypted", ex);
}
return null;
}
protected byte[] decryptPayload(Element root,
byte[] secretKeyBytes,
String symEncAlgo) throws WSSecurityException {
SecretKey key = WSSecurityUtil.prepareSecretKey(symEncAlgo, secretKeyBytes);
try {
XMLCipher xmlCipher =
EncryptionUtils.initXMLCipher(symEncAlgo, XMLCipher.DECRYPT_MODE, key);
return xmlCipher.decryptToByteArray(root);
} catch (XMLEncryptionException ex) {
throw new WSSecurityException(
WSSecurityException.UNSUPPORTED_ALGORITHM, null, null, ex
);
}
}
public void setEncryptionProperties(EncryptionProperties properties) {
this.encProps = properties;
}
}