| /** |
| * 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.security; |
| |
| import java.util.LinkedList; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Set; |
| import java.util.HashSet; |
| import java.util.concurrent.ConcurrentHashMap; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| |
| |
| /** |
| * Class that caches the netgroups and inverts group-to-user map |
| * to user-to-group map |
| */ |
| public class NetgroupCache { |
| |
| private static final Log LOG = LogFactory.getLog(NetgroupCache.class); |
| |
| private static boolean netgroupToUsersMapUpdated = true; |
| private static Map<String, Set<String>> netgroupToUsersMap = |
| new ConcurrentHashMap<String, Set<String>>(); |
| |
| private static Map<String, Set<String>> userToNetgroupsMap = |
| new ConcurrentHashMap<String, Set<String>>(); |
| |
| |
| public void getNetgroups(final String user, |
| List<String> groups) { |
| if(netgroupToUsersMapUpdated) { |
| netgroupToUsersMapUpdated = false; // at the beginning to avoid race |
| //update userToNetgroupsMap |
| for(String netgroup : netgroupToUsersMap.keySet()) { |
| for(String netuser : netgroupToUsersMap.get(netgroup)) { |
| // add to userToNetgroupsMap |
| if(!userToNetgroupsMap.containsKey(netuser)) { |
| userToNetgroupsMap.put(netuser, new HashSet<String>()); |
| } |
| userToNetgroupsMap.get(netuser).add(netgroup); |
| } |
| } |
| } |
| if(userToNetgroupsMap.containsKey(user)) { |
| for(String netgroup : userToNetgroupsMap.get(user)) { |
| groups.add(netgroup); |
| } |
| } |
| } |
| |
| public List<String> getNetgroupNames() { |
| return new LinkedList<String>(netgroupToUsersMap.keySet()); |
| } |
| |
| public boolean isCached(String group) { |
| return netgroupToUsersMap.containsKey(group); |
| } |
| |
| public void clear() { |
| netgroupToUsersMap.clear(); |
| } |
| |
| public void add(String group, List<String> users) { |
| if(!isCached(group)) { |
| netgroupToUsersMap.put(group, new HashSet<String>()); |
| for(String user: users) { |
| netgroupToUsersMap.get(group).add(user); |
| } |
| } |
| netgroupToUsersMapUpdated = true; // at the end to avoid race |
| } |
| } |