/*
* $Header: /home/cvs/jakarta-commons/httpclient/src/test/org/apache/commons/httpclient/server/ProxyAuthRequestHandler.java,v 1.1.2.2 2004/02/22 18:21:18 olegk Exp $
* $Revision: 1.1.2.2 $
* $Date: 2004/02/22 18:21:18 $
*
* ====================================================================
*
* Copyright 1999-2004 The Apache Software Foundation
*
* Licensed 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
* [Additional notices, if required by prior licensing conditions]
*
*/
package org.apache.commons.httpclient.server;
import java.io.IOException;
import org.apache.commons.httpclient.Credentials;
import org.apache.commons.httpclient.Header;
import org.apache.commons.httpclient.auth.AuthenticationException;
import org.apache.commons.httpclient.auth.BasicScheme;
import org.apache.commons.httpclient.auth.HttpAuthenticator;
import org.apache.commons.httpclient.auth.MalformedChallengeException;
/**
* This request handler guards access to a proxy when used in a
* request handler chain. It checks the headers for valid credentials
* and performs the authentication handshake if necessary.
*
* @author Ortwin Glueck
*/
public class ProxyAuthRequestHandler implements HttpRequestHandler {
private Credentials credentials;
/**
* TODO replace creds parameter with a class specific to an auth scheme encapsulating all required information for a specific scheme
* @param creds
*/
public ProxyAuthRequestHandler(Credentials creds) {
if (creds == null) throw new IllegalArgumentException("Credentials can not be null");
this.credentials = creds;
}
public boolean processRequest(SimpleHttpServerConnection conn)
throws IOException {
Header[] headers = conn.getHeaders();
Header clientAuth = findHeader(headers, HttpAuthenticator.PROXY_AUTH_RESP);
if (clientAuth != null) {
boolean ok = checkAuthorization(clientAuth);
if (ok) conn.connectionKeepAlive();
return !ok;
} else {
performHandshake(conn);
}
return true;
}
/**
* @param conn
*/
private void performHandshake(SimpleHttpServerConnection conn) throws IOException {
Header challenge = createChallenge();
ResponseWriter out = conn.getWriter();
out.println("HTTP/1.1 407 Proxy Authentication Required");
out.print(challenge.toExternalForm());
out.print(new Header("Proxy-Connection", "Keep-Alive").toExternalForm());
out.print(new Header("Content-Length", "0").toExternalForm());
out.println();
out.flush();
conn.connectionKeepAlive();
}
/**
*
* @return
*/
private Header createChallenge() {
Header header = new Header();
header.setName(HttpAuthenticator.PROXY_AUTH);
//TODO add more auth schemes
String challenge = "basic realm=test";
header.setValue(challenge);
return header;
}
/**
* Checks if the credentials provided by the client match the required credentials
* @return true if the client is authorized, false if not.
* @param clientAuth
*/
private boolean checkAuthorization(Header clientAuth) {
// TODO Auto-generated method stub
BasicScheme scheme;
try {
scheme = new BasicScheme("basic realm=test");
String expectedAuthString = scheme.authenticate(credentials, null, null);
return expectedAuthString.equals(clientAuth.getValue());
} catch (MalformedChallengeException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (AuthenticationException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return false;
}
private Header findHeader(Header[] headers, String name) {
for(int i=0; i<headers.length; i++) {
Header header = headers[i];
if (header.getName().equalsIgnoreCase(name)) return header;
}
return null;
}
}