| /** |
| * 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 |
| * <p> |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * <p> |
| * 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.security; |
| |
| import org.apache.hadoop.security.authentication.server.AuthenticationFilter; |
| import org.apache.hadoop.security.authorize.AuthorizationException; |
| import org.apache.hadoop.security.authorize.ProxyUsers; |
| import org.apache.hadoop.util.HttpExceptionUtils; |
| import org.apache.http.NameValuePair; |
| import org.apache.http.client.utils.URLEncodedUtils; |
| |
| import javax.servlet.FilterChain; |
| import javax.servlet.ServletException; |
| import javax.servlet.http.HttpServletRequest; |
| import javax.servlet.http.HttpServletRequestWrapper; |
| import javax.servlet.http.HttpServletResponse; |
| import java.io.IOException; |
| import java.nio.charset.Charset; |
| import java.util.List; |
| |
| /** |
| * Extend the function of {@link AuthenticationFilter} to |
| * support authorizing proxy user. If the query string |
| * contains doAs parameter, then check the proxy user, |
| * otherwise do the next filter. |
| */ |
| public class AuthenticationWithProxyUserFilter extends AuthenticationFilter { |
| |
| /** |
| * Constant used in URL's query string to perform a proxy user request, the |
| * value of the <code>DO_AS</code> parameter is the user the request will be |
| * done on behalf of. |
| */ |
| private static final String DO_AS = "doAs"; |
| |
| private static final Charset UTF8_CHARSET = Charset.forName("UTF-8"); |
| |
| |
| /** |
| * This method provide the ability to do pre/post tasks |
| * in filter chain. Override this method to authorize |
| * proxy user between AuthenticationFilter and next filter. |
| * @param filterChain the filter chain object. |
| * @param request the request object. |
| * @param response the response object. |
| * |
| * @throws IOException |
| * @throws ServletException |
| */ |
| @Override |
| protected void doFilter(FilterChain filterChain, HttpServletRequest request, |
| HttpServletResponse response) throws IOException, ServletException { |
| |
| // authorize proxy user before calling next filter. |
| String proxyUser = getDoAs(request); |
| if (proxyUser != null) { |
| UserGroupInformation realUser = |
| UserGroupInformation.createRemoteUser(request.getRemoteUser()); |
| UserGroupInformation proxyUserInfo = |
| UserGroupInformation.createProxyUser(proxyUser, realUser); |
| |
| try { |
| ProxyUsers.authorize(proxyUserInfo, request.getRemoteAddr()); |
| } catch (AuthorizationException ex) { |
| HttpExceptionUtils.createServletExceptionResponse(response, |
| HttpServletResponse.SC_FORBIDDEN, ex); |
| // stop filter chain if there is an Authorization Exception. |
| return; |
| } |
| |
| final UserGroupInformation finalProxyUser = proxyUserInfo; |
| // Change the remote user after proxy user is authorized. |
| request = new HttpServletRequestWrapper(request) { |
| @Override |
| public String getRemoteUser() { |
| return finalProxyUser.getUserName(); |
| } |
| }; |
| |
| } |
| filterChain.doFilter(request, response); |
| } |
| |
| /** |
| * Get proxy user from query string. |
| * @param request the request object |
| * @return proxy user |
| */ |
| public static String getDoAs(HttpServletRequest request) { |
| String queryString = request.getQueryString(); |
| if (queryString == null) { |
| return null; |
| } |
| List<NameValuePair> list = URLEncodedUtils.parse(queryString, UTF8_CHARSET); |
| if (list != null) { |
| for (NameValuePair nv : list) { |
| if (DO_AS.equalsIgnoreCase(nv.getName())) { |
| return nv.getValue(); |
| } |
| } |
| } |
| return null; |
| } |
| } |