/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. 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. For additional information regarding
* copyright in this work, please see the NOTICE file in the top level
* directory of this distribution.
*/
package org.apache.abdera.security.util.filters;
import org.apache.abdera.protocol.server.FilterChain;
import org.apache.abdera.protocol.server.RequestContext;
import org.apache.abdera.protocol.server.ResponseContext;
import org.apache.abdera.protocol.server.RequestContext.Scope;
import org.apache.abdera.security.Encryption;
import org.apache.abdera.security.EncryptionOptions;
import org.apache.abdera.security.util.Constants;
import org.apache.abdera.security.util.DHContext;
/**
* A filter implementation that allows requests to be encrypted using Diffie-Hellman
* key negotiation. A client first uses GET/HEAD/OPTIONS to get the servers DH
* information, then sends an encrypted request containing it's DH information.
* The server can then decrypt and process the request.
*
* Note: this is currently untested.
*/
public class DHEncryptedRequestFilter
extends AbstractEncryptedRequestFilter {
public DHEncryptedRequestFilter() {
super();
}
public DHEncryptedRequestFilter(String... methods) {
super(methods);
}
public void bootstrap(
RequestContext request) {}
public ResponseContext filter(
RequestContext request,
FilterChain chain) {
ResponseContext response = super.filter(request, chain);
String method = request.getMethod();
// include a Accept-Encryption header in the response to GET, HEAD and OPTIONS requests
// the header will specify all the information the client needs to construct
// it's own DH context and encrypt the request
if ("GET".equalsIgnoreCase(method) ||
"HEAD".equalsIgnoreCase(method) ||
"OPTIONS".equalsIgnoreCase(method)) {
DHContext context =
(DHContext) request.getAttribute(
Scope.SESSION,
"dhcontext");
if (context == null) {
context = new DHContext();
request.setAttribute(Scope.SESSION, "dhcontext", context);
}
response.setHeader(
Constants.ACCEPT_ENCRYPTION,
context.getRequestString());
}
return response;
}
protected Object initArg(RequestContext request) {
DHContext context =
(DHContext) request.getAttribute(
Scope.SESSION,
"dhcontext");
String dh = request.getHeader(Constants.CONTENT_ENCRYPTED);
if (context != null && dh != null && dh.length() > 0) {
try {
context.setPublicKey(dh);
} catch (Exception e) {}
}
return context;
}
protected EncryptionOptions initEncryptionOptions(
RequestContext request,
Encryption encryption,
Object arg) {
EncryptionOptions options = null;
if (arg != null && arg instanceof DHContext) {
try {
options = ((DHContext)arg).getEncryptionOptions(encryption);
} catch (Exception e) {}
}
return options;
}
}