| /** |
| * 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.sqoop.util; |
| |
| import java.security.Permission; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| |
| /** |
| * A SecurityManager used to run subprocesses and disallow certain actions. |
| * |
| * This specifically disallows System.exit(). |
| * |
| * This SecurityManager will also check with any existing SecurityManager as |
| * to the validity of any permissions. The SubprocessSecurityManager should be |
| * installed with the install() method, which will retain a handle to any |
| * previously-installed SecurityManager instance. |
| * |
| * When this SecurityManager is no longer necessary, the uninstall() method |
| * should be used which reinstates the previous SecurityManager as the active |
| * SecurityManager. |
| */ |
| public class SubprocessSecurityManager extends SecurityManager { |
| |
| public static final Log LOG = LogFactory.getLog( |
| SubprocessSecurityManager.class.getName()); |
| |
| private SecurityManager parentSecurityManager; |
| private boolean installed; |
| private boolean allowReplacement; |
| |
| public SubprocessSecurityManager() { |
| this.installed = false; |
| this.allowReplacement = false; |
| } |
| |
| /** |
| * Install this SecurityManager and retain a reference to any |
| * previously-installed SecurityManager. |
| */ |
| public void install() { |
| LOG.debug("Installing subprocess security manager"); |
| this.parentSecurityManager = System.getSecurityManager(); |
| System.setSecurityManager(this); |
| this.installed = true; |
| } |
| |
| /** |
| * Restore an existing SecurityManager, uninstalling this one. |
| */ |
| public void uninstall() { |
| if (this.installed) { |
| LOG.debug("Uninstalling subprocess security manager"); |
| this.allowReplacement = true; |
| System.setSecurityManager(this.parentSecurityManager); |
| } |
| } |
| |
| @Override |
| /** |
| * Disallow the capability to call System.exit() or otherwise |
| * terminate the JVM. |
| */ |
| public void checkExit(int status) { |
| LOG.debug("Rejecting System.exit call with status=" + status); |
| throw new org.apache.sqoop.util.ExitSecurityException(status); |
| } |
| |
| @Override |
| /** |
| * Check a particular permission. Checks with this SecurityManager |
| * as well as any previously-installed manager. |
| * |
| * @param perm the Permission to check; must not be null. |
| */ |
| public void checkPermission(Permission perm) { |
| if (null != this.parentSecurityManager) { |
| // Check if the prior SecurityManager would have rejected this. |
| parentSecurityManager.checkPermission(perm); |
| } |
| |
| if (!allowReplacement && perm.getName().equals("setSecurityManager")) { |
| throw new SecurityException("Cannot replace security manager"); |
| } |
| } |
| |
| } |
| |