/**
* 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.hadoop.yarn.server.webproxy.amfilter;
import java.io.IOException;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.HashSet;
import java.util.Set;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.yarn.server.webproxy.WebAppProxyServlet;
public class AmIpFilter implements Filter {
private static final Log LOG = LogFactory.getLog(AmIpFilter.class);
public static final String PROXY_HOST = "PROXY_HOST";
public static final String PROXY_URI_BASE = "PROXY_URI_BASE";
//update the proxy IP list about every 5 min
private static final long updateInterval = 5 * 60 * 1000;
private String proxyHost;
private Set<String> proxyAddresses = null;
private long lastUpdate;
private String proxyUriBase;
@Override
public void init(FilterConfig conf) throws ServletException {
proxyHost = conf.getInitParameter(PROXY_HOST);
proxyUriBase = conf.getInitParameter(PROXY_URI_BASE);
}
protected Set<String> getProxyAddresses() throws ServletException {
long now = System.currentTimeMillis();
synchronized(this) {
if(proxyAddresses == null || (lastUpdate + updateInterval) >= now) {
try {
proxyAddresses = new HashSet<String>();
for(InetAddress add : InetAddress.getAllByName(proxyHost)) {
proxyAddresses.add(add.getHostAddress());
}
lastUpdate = now;
} catch (UnknownHostException e) {
throw new ServletException("Could not locate "+proxyHost, e);
}
}
return proxyAddresses;
}
}
@Override
public void destroy() {
//Empty
}
@Override
public void doFilter(ServletRequest req, ServletResponse resp,
FilterChain chain) throws IOException, ServletException {
if(!(req instanceof HttpServletRequest)) {
throw new ServletException("This filter only works for HTTP/HTTPS");
}
HttpServletRequest httpReq = (HttpServletRequest)req;
HttpServletResponse httpResp = (HttpServletResponse)resp;
if(!getProxyAddresses().contains(httpReq.getRemoteAddr())) {
String redirectUrl = httpResp.encodeRedirectURL(proxyUriBase +
httpReq.getRequestURI());
httpResp.sendRedirect(redirectUrl);
return;
}
String user = null;
if (httpReq.getCookies() != null) {
for(Cookie c: httpReq.getCookies()) {
if(WebAppProxyServlet.PROXY_USER_COOKIE_NAME.equals(c.getName())){
user = c.getValue();
break;
}
}
}
if(user == null) {
LOG.warn("Could not find "+WebAppProxyServlet.PROXY_USER_COOKIE_NAME
+" cookie, so user will not be set");
chain.doFilter(req, resp);
} else {
final AmIpPrincipal principal = new AmIpPrincipal(user);
ServletRequest requestWrapper = new AmIpServletRequestWrapper(httpReq,
principal);
chain.doFilter(requestWrapper, resp);
}
}
}