SecurityManager.java revision 1714
0N/A * Copyright 1995-2006 Sun Microsystems, Inc. All Rights Reserved. 0N/A * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 0N/A * This code is free software; you can redistribute it and/or modify it 0N/A * under the terms of the GNU General Public License version 2 only, as 0N/A * published by the Free Software Foundation. Sun designates this 0N/A * particular file as subject to the "Classpath" exception as provided 0N/A * by Sun in the LICENSE file that accompanied this code. 0N/A * This code is distributed in the hope that it will be useful, but WITHOUT 0N/A * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 0N/A * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 0N/A * version 2 for more details (a copy is included in the LICENSE file that 0N/A * accompanied this code). 0N/A * You should have received a copy of the GNU General Public License version 0N/A * 2 along with this work; if not, write to the Free Software Foundation, 0N/A * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 0N/A * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 0N/A * CA 95054 USA or visit www.sun.com if you need additional information or 0N/A * have any questions. * The security manager is a class that allows * applications to implement a security policy. It allows an * application to determine, before performing a possibly unsafe or * sensitive operation, what the operation is and whether * it is being attempted in a security context that allows the * operation to be performed. The * application can allow or disallow the operation. * The <code>SecurityManager</code> class contains many methods with * names that begin with the word <code>check</code>. These methods * are called by various methods in the Java libraries before those * methods perform certain potentially sensitive operations. The * invocation of such a <code>check</code> method typically looks like this: * SecurityManager security = System.getSecurityManager(); * if (security != null) { * security.check<i>XXX</i>(argument, . . . ); * The security manager is thereby given an opportunity to prevent * completion of the operation by throwing an exception. A security * manager routine simply returns if the operation is permitted, but * throws a <code>SecurityException</code> if the operation is not * permitted. The only exception to this convention is * <code>checkTopLevelWindow</code>, which returns a * <code>boolean</code> value. * The current security manager is set by the * <code>setSecurityManager</code> method in class * <code>System</code>. The current security manager is obtained * by the <code>getSecurityManager</code> method. * {@link SecurityManager#checkPermission(java.security.Permission)} * determines whether an access request indicated by a specified * permission should be granted or denied. The * default implementation calls * AccessController.checkPermission(perm); * If a requested access is allowed, * <code>checkPermission</code> returns quietly. If denied, a * <code>SecurityException</code> is thrown. * As of Java 2 SDK v1.2, the default implementation of each of the other * <code>check</code> methods in <code>SecurityManager</code> is to * call the <code>SecurityManager checkPermission</code> method * to determine if the calling thread has permission to perform the requested * Note that the <code>checkPermission</code> method with * just a single permission argument always performs security checks * within the context of the currently executing thread. * Sometimes a security check that should be made within a given context * will actually need to be done from within a * <i>different</i> context (for example, from within a worker thread). * The {@link SecurityManager#getSecurityContext getSecurityContext} method * and the {@link SecurityManager#checkPermission(java.security.Permission, * java.lang.Object) checkPermission} * method that includes a context argument are provided * for this situation. The * <code>getSecurityContext</code> method returns a "snapshot" * of the current calling context. (The default implementation * returns an AccessControlContext object.) A sample call is * SecurityManager sm = System.getSecurityManager(); * if (sm != null) context = sm.getSecurityContext(); * The <code>checkPermission</code> method * that takes a context object in addition to a permission * makes access decisions based on that context, * rather than on that of the current execution thread. * Code within a different context can thus call that method, * passing the permission and the * previously-saved context object. A sample call, using the * SecurityManager <code>sm</code> obtained as in the previous example, * if (sm != null) sm.checkPermission(permission, context); * <p>Permissions fall into these categories: File, Socket, Net, * Security, Runtime, Property, AWT, Reflect, and Serializable. * The classes managing these various * permission categories are <code>java.io.FilePermission</code>, * <code>java.net.SocketPermission</code>, * <code>java.net.NetPermission</code>, * <code>java.security.SecurityPermission</code>, * <code>java.lang.RuntimePermission</code>, * <code>java.util.PropertyPermission</code>, * <code>java.awt.AWTPermission</code>, * <code>java.lang.reflect.ReflectPermission</code>, and * <code>java.io.SerializablePermission</code>. * <p>All but the first two (FilePermission and SocketPermission) are * subclasses of <code>java.security.BasicPermission</code>, which itself * is an abstract subclass of the * top-level class for permissions, which is * <code>java.security.Permission</code>. BasicPermission defines the * functionality needed for all permissions that contain a name * that follows the hierarchical property naming convention * (for example, "exitVM", "setFactory", "queuePrintJob", etc). * may appear at the end of the name, following a ".", or by itself, to * signify a wildcard match. For example: "a.*" or "*" is valid, * "*a" or "a*b" is not valid. * <p>FilePermission and SocketPermission are subclasses of the * top-level class for permissions * (<code>java.security.Permission</code>). Classes like these * that have a more complicated name syntax than that used by * BasicPermission subclass directly from Permission rather than from * BasicPermission. For example, * for a <code>java.io.FilePermission</code> object, the permission name is * the path name of a file (or directory). * <p>Some of the permission classes have an "actions" list that tells * the actions that are permitted for the object. For example, * for a <code>java.io.FilePermission</code> object, the actions list * (such as "read, write") specifies which actions are granted for the * specified file (or for files in the specified directory). * <p>Other permission classes are for "named" permissions - * ones that contain a name but no actions list; you either have the * named permission or you don't. * <p>Note: There is also a <code>java.security.AllPermission</code> * permission that implies all permissions. It exists to simplify the work * of system administrators who might need to perform multiple * tasks that require all (or numerous) permissions. * Permissions in the JDK</a> for permission-related information. * This document includes, for example, a table listing the various SecurityManager * <code>check</code> methods and the permission(s) the default * implementation of each such method requires. * It also contains a table of all the version 1.2 methods * that require permissions, and for each such method tells * which permission it requires. * For more information about <code>SecurityManager</code> changes made in * the JDK and advice regarding porting of 1.1-style security managers, * @author Arthur van Hoff * @author Roland Schemers * @see java.lang.ClassLoader * @see java.lang.SecurityException * @see java.lang.SecurityManager#checkTopLevelWindow(java.lang.Object) * @see java.lang.System#getSecurityManager() getSecurityManager * @see java.lang.System#setSecurityManager(java.lang.SecurityManager) * @see java.security.AccessController AccessController * @see java.security.AccessControlContext AccessControlContext * @see java.security.AccessControlException AccessControlException * @see java.security.Permission * @see java.security.BasicPermission * @see java.io.FilePermission * @see java.net.SocketPermission * @see java.util.PropertyPermission * @see java.lang.RuntimePermission * @see java.awt.AWTPermission * @see java.security.Policy Policy * @see java.security.SecurityPermission SecurityPermission * @see java.security.ProtectionDomain * This field is <code>true</code> if there is a security check in * progress; <code>false</code> otherwise. * @deprecated This type of security checking is not recommended. * It is recommended that the <code>checkPermission</code> * Have we been initialized. Effective against finalizer attacks. * returns true if the current context has been granted AllPermission * Tests if there is a security check in progress. * @return the value of the <code>inCheck</code> field. This field * should contain <code>true</code> if a security check is * <code>false</code> otherwise. * @see java.lang.SecurityManager#inCheck * @deprecated This type of security checking is not recommended. * It is recommended that the <code>checkPermission</code> * Constructs a new <code>SecurityManager</code>. * <p> If there is a security manager already installed, this method first * calls the security manager's <code>checkPermission</code> method * with the <code>RuntimePermission("createSecurityManager")</code> * permission to ensure the calling thread has permission to create a new * This may result in throwing a <code>SecurityException</code>. * @exception java.lang.SecurityException if a security manager already * exists and its <code>checkPermission</code> method * doesn't allow creation of a new security manager. * @see java.lang.System#getSecurityManager() * @see #checkPermission(java.security.Permission) checkPermission * @see java.lang.RuntimePermission // ask the currently installed security manager if we (
"createSecurityManager"));
* Returns the current execution stack as an array of classes. * The length of the array is the number of methods on the execution * stack. The element at index <code>0</code> is the class of the * currently executing method, the element at index <code>1</code> is * the class of that method's caller, and so on. * @return the execution stack. * Returns the class loader of the most recently executing method from * a class defined using a non-system class loader. A non-system * class loader is defined as being a class loader that is not equal to * the system class loader (as returned * by {@link ClassLoader#getSystemClassLoader}) or one of its ancestors. * This method will return * <code>null</code> in the following three cases:<p> * <li>All methods on the execution stack are from classes * defined using the system class loader or one of its ancestors. * <li>All methods on the execution stack up to the first * (see {@link java.security.AccessController#doPrivileged}) * defined using the system class loader or one of its ancestors. * <li> A call to <code>checkPermission</code> with * <code>java.security.AllPermission</code> does not * result in a SecurityException. * @return the class loader of the most recent occurrence on the stack * of a method from a class defined using a non-system class * @deprecated This type of security checking is not recommended. * It is recommended that the <code>checkPermission</code> * @see java.lang.ClassLoader#getSystemClassLoader() getSystemClassLoader * @see #checkPermission(java.security.Permission) checkPermission * Returns the class of the most recently executing method from * a class defined using a non-system class loader. A non-system * class loader is defined as being a class loader that is not equal to * the system class loader (as returned * by {@link ClassLoader#getSystemClassLoader}) or one of its ancestors. * This method will return * <code>null</code> in the following three cases:<p> * <li>All methods on the execution stack are from classes * defined using the system class loader or one of its ancestors. * <li>All methods on the execution stack up to the first * (see {@link java.security.AccessController#doPrivileged}) * defined using the system class loader or one of its ancestors. * <li> A call to <code>checkPermission</code> with * <code>java.security.AllPermission</code> does not * result in a SecurityException. * @return the class of the most recent occurrence on the stack * of a method from a class defined using a non-system class * @deprecated This type of security checking is not recommended. * It is recommended that the <code>checkPermission</code> * @see java.lang.ClassLoader#getSystemClassLoader() getSystemClassLoader * @see #checkPermission(java.security.Permission) checkPermission * Returns the stack depth of the specified class. * @param name the fully qualified name of the class to search for. * @return the depth on the stack frame of the first occurrence of a * method from a class with the specified name; * <code>-1</code> if such a frame cannot be found. * @deprecated This type of security checking is not recommended. * It is recommended that the <code>checkPermission</code> * Returns the stack depth of the most recently executing method * from a class defined using a non-system class loader. A non-system * class loader is defined as being a class loader that is not equal to * the system class loader (as returned * by {@link ClassLoader#getSystemClassLoader}) or one of its ancestors. * This method will return * -1 in the following three cases:<p> * <li>All methods on the execution stack are from classes * defined using the system class loader or one of its ancestors. * <li>All methods on the execution stack up to the first * (see {@link java.security.AccessController#doPrivileged}) * defined using the system class loader or one of its ancestors. * <li> A call to <code>checkPermission</code> with * <code>java.security.AllPermission</code> does not * result in a SecurityException. * @return the depth on the stack frame of the most recent occurrence of * a method from a class defined using a non-system class loader. * @deprecated This type of security checking is not recommended. * It is recommended that the <code>checkPermission</code> * @see java.lang.ClassLoader#getSystemClassLoader() getSystemClassLoader * @see #checkPermission(java.security.Permission) checkPermission depth--;
// make sure we don't include ourself * Tests if a method from a class with the specified * name is on the execution stack. * @param name the fully qualified name of the class. * @return <code>true</code> if a method from a class with the specified * name is on the execution stack; <code>false</code> otherwise. * @deprecated This type of security checking is not recommended. * It is recommended that the <code>checkPermission</code> * Basically, tests if a method from a class defined using a * class loader is on the execution stack. * @return <code>true</code> if a call to <code>currentClassLoader</code> * has a non-null return value. * @deprecated This type of security checking is not recommended. * It is recommended that the <code>checkPermission</code> * @see #currentClassLoader() currentClassLoader * Creates an object that encapsulates the current execution * environment. The result of this method is used, for example, by the * three-argument <code>checkConnect</code> method and by the * two-argument <code>checkRead</code> method. * These methods are needed because a trusted method may be called * on to read a file or open a socket on behalf of another method. * The trusted method needs to determine if the other (possibly * untrusted) method would be allowed to perform the operation on its * <p> The default implementation of this method is to return * an <code>AccessControlContext</code> object. * @return an implementation-dependent object that encapsulates * sufficient information about the current execution environment * to perform some security checks later. * @see java.lang.SecurityManager#checkConnect(java.lang.String, int, * java.lang.Object) checkConnect * @see java.lang.SecurityManager#checkRead(java.lang.String, * java.lang.Object) checkRead * @see java.security.AccessControlContext AccessControlContext * Throws a <code>SecurityException</code> if the requested * access, specified by the given permission, is not permitted based * on the security policy currently in effect. * This method calls <code>AccessController.checkPermission</code> * with the given permission. * @param perm the requested permission. * @exception SecurityException if access is not permitted based on * the current security policy. * @exception NullPointerException if the permission argument is * Throws a <code>SecurityException</code> if the * specified security context is denied access to the resource * specified by the given permission. * The context must be a security * context returned by a previous call to * <code>getSecurityContext</code> and the access control * decision is based upon the configured security policy for * If <code>context</code> is an instance of * <code>AccessControlContext</code> then the * <code>AccessControlContext.checkPermission</code> method is * invoked with the specified permission. * If <code>context</code> is not an instance of * <code>AccessControlContext</code> then a * <code>SecurityException</code> is thrown. * @param perm the specified permission * @param context a system-dependent security context. * @exception SecurityException if the specified security context * is not an instance of <code>AccessControlContext</code> * (e.g., is <code>null</code>), or is denied access to the * resource specified by the given permission. * @exception NullPointerException if the permission argument is * @see java.lang.SecurityManager#getSecurityContext() * @see java.security.AccessControlContext#checkPermission(java.security.Permission) * Throws a <code>SecurityException</code> if the * calling thread is not allowed to create a new class loader. * This method calls <code>checkPermission</code> with the * <code>RuntimePermission("createClassLoader")</code> * If you override this method, then you should make a call to * <code>super.checkCreateClassLoader</code> * at the point the overridden method would normally throw an * @exception SecurityException if the calling thread does not * to create a new class loader. * @see java.lang.ClassLoader#ClassLoader() * @see #checkPermission(java.security.Permission) checkPermission * reference to the root thread group, used for the checkAccess * Throws a <code>SecurityException</code> if the * calling thread is not allowed to modify the thread argument. * This method is invoked for the current security manager by the * <code>stop</code>, <code>suspend</code>, <code>resume</code>, * <code>setPriority</code>, <code>setName</code>, and * <code>setDaemon</code> methods of class <code>Thread</code>. * If the thread argument is a system thread (belongs to * the thread group with a <code>null</code> parent) then * this method calls <code>checkPermission</code> with the * <code>RuntimePermission("modifyThread")</code> permission. * If the thread argument is <i>not</i> a system thread, * this method just returns silently. * Applications that want a stricter policy should override this * method. If this method is overridden, the method that overrides * it should additionally check to see if the calling thread has the * <code>RuntimePermission("modifyThread")</code> permission, and * if so, return silently. This is to ensure that code granted * that permission (such as the JDK itself) is allowed to * If this method is overridden, then * <code>super.checkAccess</code> should * be called by the first statement in the overridden method, or the * equivalent security check should be placed in the overridden method. * @param t the thread to be checked. * @exception SecurityException if the calling thread does not have * permission to modify the thread. * @exception NullPointerException if the thread argument is * @see java.lang.Thread#resume() resume * @see java.lang.Thread#setDaemon(boolean) setDaemon * @see java.lang.Thread#setName(java.lang.String) setName * @see java.lang.Thread#setPriority(int) setPriority * @see java.lang.Thread#stop() stop * @see java.lang.Thread#suspend() suspend * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to modify the thread group argument. * This method is invoked for the current security manager when a * new child thread or child thread group is created, and by the * <code>setDaemon</code>, <code>setMaxPriority</code>, * <code>stop</code>, <code>suspend</code>, <code>resume</code>, and * <code>destroy</code> methods of class <code>ThreadGroup</code>. * If the thread group argument is the system thread group ( * has a <code>null</code> parent) then * this method calls <code>checkPermission</code> with the * <code>RuntimePermission("modifyThreadGroup")</code> permission. * If the thread group argument is <i>not</i> the system thread group, * this method just returns silently. * Applications that want a stricter policy should override this * method. If this method is overridden, the method that overrides * it should additionally check to see if the calling thread has the * <code>RuntimePermission("modifyThreadGroup")</code> permission, and * if so, return silently. This is to ensure that code granted * that permission (such as the JDK itself) is allowed to * If this method is overridden, then * <code>super.checkAccess</code> should * be called by the first statement in the overridden method, or the * equivalent security check should be placed in the overridden method. * @param g the thread group to be checked. * @exception SecurityException if the calling thread does not have * permission to modify the thread group. * @exception NullPointerException if the thread group argument is * @see java.lang.ThreadGroup#destroy() destroy * @see java.lang.ThreadGroup#resume() resume * @see java.lang.ThreadGroup#setDaemon(boolean) setDaemon * @see java.lang.ThreadGroup#setMaxPriority(int) setMaxPriority * @see java.lang.ThreadGroup#stop() stop * @see java.lang.ThreadGroup#suspend() suspend * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to cause the Java Virtual Machine to * halt with the specified status code. * This method is invoked for the current security manager by the * <code>exit</code> method of class <code>Runtime</code>. A status * of <code>0</code> indicates success; other values indicate various * This method calls <code>checkPermission</code> with the * <code>RuntimePermission("exitVM."+status)</code> permission. * If you override this method, then you should make a call to * <code>super.checkExit</code> * at the point the overridden method would normally throw an * @param status the exit status. * @exception SecurityException if the calling thread does not have * permission to halt the Java Virtual Machine with * @see java.lang.Runtime#exit(int) exit * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to create a subprocess. * This method is invoked for the current security manager by the * <code>exec</code> methods of class <code>Runtime</code>. * This method calls <code>checkPermission</code> with the * <code>FilePermission(cmd,"execute")</code> permission * if cmd is an absolute path, otherwise it calls * <code>checkPermission</code> with * <code>FilePermission("<<ALL FILES>>","execute")</code>. * If you override this method, then you should make a call to * <code>super.checkExec</code> * at the point the overridden method would normally throw an * @param cmd the specified system command. * @exception SecurityException if the calling thread does not have * permission to create a subprocess. * @exception NullPointerException if the <code>cmd</code> argument is * @see java.lang.Runtime#exec(java.lang.String) * @see java.lang.Runtime#exec(java.lang.String, java.lang.String[]) * @see java.lang.Runtime#exec(java.lang.String[]) * @see java.lang.Runtime#exec(java.lang.String[], java.lang.String[]) * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to dynamic link the library code * specified by the string argument file. The argument is either a * simple library name or a complete filename. * This method is invoked for the current security manager by * methods <code>load</code> and <code>loadLibrary</code> of class * This method calls <code>checkPermission</code> with the * <code>RuntimePermission("loadLibrary."+lib)</code> permission. * If you override this method, then you should make a call to * <code>super.checkLink</code> * at the point the overridden method would normally throw an * @param lib the name of the library. * @exception SecurityException if the calling thread does not have * permission to dynamically link the library. * @exception NullPointerException if the <code>lib</code> argument is * @see java.lang.Runtime#load(java.lang.String) * @see java.lang.Runtime#loadLibrary(java.lang.String) * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to read from the specified file * This method calls <code>checkPermission</code> with the * <code>RuntimePermission("readFileDescriptor")</code> * If you override this method, then you should make a call to * <code>super.checkRead</code> * at the point the overridden method would normally throw an * @param fd the system-dependent file descriptor. * @exception SecurityException if the calling thread does not have * permission to access the specified file descriptor. * @exception NullPointerException if the file descriptor argument is * @see java.io.FileDescriptor * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to read the file specified by the * This method calls <code>checkPermission</code> with the * <code>FilePermission(file,"read")</code> permission. * If you override this method, then you should make a call to * <code>super.checkRead</code> * at the point the overridden method would normally throw an * @param file the system-dependent file name. * @exception SecurityException if the calling thread does not have * permission to access the specified file. * @exception NullPointerException if the <code>file</code> argument is * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * specified security context is not allowed to read the file * specified by the string argument. The context must be a security * context returned by a previous call to * <code>getSecurityContext</code>. * <p> If <code>context</code> is an instance of * <code>AccessControlContext</code> then the * <code>AccessControlContext.checkPermission</code> method will * be invoked with the <code>FilePermission(file,"read")</code> permission. * <p> If <code>context</code> is not an instance of * <code>AccessControlContext</code> then a * <code>SecurityException</code> is thrown. * If you override this method, then you should make a call to * <code>super.checkRead</code> * at the point the overridden method would normally throw an * @param file the system-dependent filename. * @param context a system-dependent security context. * @exception SecurityException if the specified security context * is not an instance of <code>AccessControlContext</code> * (e.g., is <code>null</code>), or does not have permission * to read the specified file. * @exception NullPointerException if the <code>file</code> argument is * @see java.lang.SecurityManager#getSecurityContext() * @see java.security.AccessControlContext#checkPermission(java.security.Permission) * Throws a <code>SecurityException</code> if the * calling thread is not allowed to write to the specified file * This method calls <code>checkPermission</code> with the * <code>RuntimePermission("writeFileDescriptor")</code> * If you override this method, then you should make a call to * <code>super.checkWrite</code> * at the point the overridden method would normally throw an * @param fd the system-dependent file descriptor. * @exception SecurityException if the calling thread does not have * permission to access the specified file descriptor. * @exception NullPointerException if the file descriptor argument is * @see java.io.FileDescriptor * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to write to the file specified by * This method calls <code>checkPermission</code> with the * <code>FilePermission(file,"write")</code> permission. * If you override this method, then you should make a call to * <code>super.checkWrite</code> * at the point the overridden method would normally throw an * @param file the system-dependent filename. * @exception SecurityException if the calling thread does not * have permission to access the specified file. * @exception NullPointerException if the <code>file</code> argument is * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to delete the specified file. * This method is invoked for the current security manager by the * <code>delete</code> method of class <code>File</code>. * This method calls <code>checkPermission</code> with the * <code>FilePermission(file,"delete")</code> permission. * If you override this method, then you should make a call to * <code>super.checkDelete</code> * at the point the overridden method would normally throw an * @param file the system-dependent filename. * @exception SecurityException if the calling thread does not * have permission to delete the file. * @exception NullPointerException if the <code>file</code> argument is * @see java.io.File#delete() * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to open a socket connection to the * specified host and port number. * A port number of <code>-1</code> indicates that the calling * method is attempting to determine the IP address of the specified * This method calls <code>checkPermission</code> with the * <code>SocketPermission(host+":"+port,"connect")</code> permission if * the port is not equal to -1. If the port is equal to -1, then * it calls <code>checkPermission</code> with the * <code>SocketPermission(host,"resolve")</code> permission. * If you override this method, then you should make a call to * <code>super.checkConnect</code> * at the point the overridden method would normally throw an * @param host the host name port to connect to. * @param port the protocol port to connect to. * @exception SecurityException if the calling thread does not have * permission to open a socket connection to the specified * <code>host</code> and <code>port</code>. * @exception NullPointerException if the <code>host</code> argument is * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * specified security context is not allowed to open a socket * connection to the specified host and port number. * A port number of <code>-1</code> indicates that the calling * method is attempting to determine the IP address of the specified * <p> If <code>context</code> is not an instance of * <code>AccessControlContext</code> then a * <code>SecurityException</code> is thrown. * Otherwise, the port number is checked. If it is not equal * to -1, the <code>context</code>'s <code>checkPermission</code> * method is called with a * <code>SocketPermission(host+":"+port,"connect")</code> permission. * If the port is equal to -1, then * the <code>context</code>'s <code>checkPermission</code> method * <code>SocketPermission(host,"resolve")</code> permission. * If you override this method, then you should make a call to * <code>super.checkConnect</code> * at the point the overridden method would normally throw an * @param host the host name port to connect to. * @param port the protocol port to connect to. * @param context a system-dependent security context. * @exception SecurityException if the specified security context * is not an instance of <code>AccessControlContext</code> * (e.g., is <code>null</code>), or does not have permission * to open a socket connection to the specified * <code>host</code> and <code>port</code>. * @exception NullPointerException if the <code>host</code> argument is * @see java.lang.SecurityManager#getSecurityContext() * @see java.security.AccessControlContext#checkPermission(java.security.Permission) * Throws a <code>SecurityException</code> if the * calling thread is not allowed to wait for a connection request on * the specified local port number. * If port is not 0, this method calls * <code>checkPermission</code> with the * <code>SocketPermission("localhost:"+port,"listen")</code>. * If port is zero, this method calls <code>checkPermission</code> * with <code>SocketPermission("localhost:1024-","listen").</code> * If you override this method, then you should make a call to * <code>super.checkListen</code> * at the point the overridden method would normally throw an * @param port the local port. * @exception SecurityException if the calling thread does not have * permission to listen on the specified port. * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not permitted to accept a socket connection from * the specified host and port number. * This method is invoked for the current security manager by the * <code>accept</code> method of class <code>ServerSocket</code>. * This method calls <code>checkPermission</code> with the * <code>SocketPermission(host+":"+port,"accept")</code> permission. * If you override this method, then you should make a call to * <code>super.checkAccept</code> * at the point the overridden method would normally throw an * @param host the host name of the socket connection. * @param port the port number of the socket connection. * @exception SecurityException if the calling thread does not have * permission to accept the connection. * @exception NullPointerException if the <code>host</code> argument is * @see java.net.ServerSocket#accept() * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to use * This method calls <code>checkPermission</code> with the * <code>java.net.SocketPermission(maddr.getHostAddress(), * "accept,connect")</code> permission. * If you override this method, then you should make a call to * <code>super.checkMulticast</code> * at the point the overridden method would normally throw an * @param maddr Internet group address to be used. * @exception SecurityException if the calling thread is not allowed to * @exception NullPointerException if the address argument is * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to use * This method calls <code>checkPermission</code> with the * <code>java.net.SocketPermission(maddr.getHostAddress(), * "accept,connect")</code> permission. * If you override this method, then you should make a call to * <code>super.checkMulticast</code> * at the point the overridden method would normally throw an * @param maddr Internet group address to be used. * @param ttl value in use, if it is multicast send. * Note: this particular implementation does not use the ttl * @exception SecurityException if the calling thread is not allowed to * @exception NullPointerException if the address argument is * @deprecated Use #checkPermission(java.security.Permission) instead * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to access or modify the system * This method is used by the <code>getProperties</code> and * <code>setProperties</code> methods of class <code>System</code>. * This method calls <code>checkPermission</code> with the * <code>PropertyPermission("*", "read,write")</code> permission. * If you override this method, then you should make a call to * <code>super.checkPropertiesAccess</code> * at the point the overridden method would normally throw an * @exception SecurityException if the calling thread does not have * permission to access or modify the system properties. * @see java.lang.System#getProperties() * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to access the system property with * the specified <code>key</code> name. * This method is used by the <code>getProperty</code> method of * class <code>System</code>. * This method calls <code>checkPermission</code> with the * <code>PropertyPermission(key, "read")</code> permission. * If you override this method, then you should make a call to * <code>super.checkPropertyAccess</code> * at the point the overridden method would normally throw an * @param key a system property key. * @exception SecurityException if the calling thread does not have * permission to access the specified system property. * @exception NullPointerException if the <code>key</code> argument is * @exception IllegalArgumentException if <code>key</code> is empty. * @see java.lang.System#getProperty(java.lang.String) * @see #checkPermission(java.security.Permission) checkPermission * Returns <code>false</code> if the calling * thread is not trusted to bring up the top-level window indicated * by the <code>window</code> argument. In this case, the caller can * still decide to show the window, but the window should include * some sort of visual warning. If the method returns * <code>true</code>, then the window can be shown without any * See class <code>Window</code> for more information on trusted and * <code>checkPermission</code> with the * <code>AWTPermission("showWindowWithoutWarningBanner")</code> permission, * and returns <code>true</code> if a SecurityException is not thrown, * otherwise it returns <code>false</code>. * If you override this method, then you should make a call to * <code>super.checkTopLevelWindow</code> * at the point the overridden method would normally return * <code>false</code>, and the value of * <code>super.checkTopLevelWindow</code> should * @param window the new window that is being created. * @return <code>true</code> if the calling thread is trusted to put up * top-level windows; <code>false</code> otherwise. * @exception NullPointerException if the <code>window</code> argument is * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to initiate a print job request. * <code>checkPermission</code> with the * <code>RuntimePermission("queuePrintJob")</code> permission. * If you override this method, then you should make a call to * <code>super.checkPrintJobAccess</code> * at the point the overridden method would normally throw an * @exception SecurityException if the calling thread does not have * permission to initiate a print job request. * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to access the system clipboard. * This method calls <code>checkPermission</code> with the * <code>AWTPermission("accessClipboard")</code> * If you override this method, then you should make a call to * <code>super.checkSystemClipboardAccess</code> * at the point the overridden method would normally throw an * @exception SecurityException if the calling thread does not have * permission to access the system clipboard. * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to access the AWT event queue. * This method calls <code>checkPermission</code> with the * <code>AWTPermission("accessEventQueue")</code> permission. * If you override this method, then you should make a call to * <code>super.checkAwtEventQueueAccess</code> * at the point the overridden method would normally throw an * @exception SecurityException if the calling thread does not have * permission to access the AWT event queue. * @see #checkPermission(java.security.Permission) checkPermission * We have an initial invalid bit (initially false) for the class * variables which tell if the cache is valid. If the underlying * java.security.Security property changes via setProperty(), the * Security class uses reflection to change the variable and thus * Locking is handled by synchronization to the * Note that cache invalidation as a result of the property change * happens without using these locks, so there may be a delay between * when a thread updates the property and when other threads updates * Throws a <code>SecurityException</code> if the * calling thread is not allowed to access the package specified by * This method is used by the <code>loadClass</code> method of class * This method first gets a list of * restricted packages by obtaining a comma-separated list from * <code>java.security.Security.getProperty("package.access")</code>, * and checks to see if <code>pkg</code> starts with or equals * any of the restricted packages. If it does, then * <code>checkPermission</code> gets called with the * <code>RuntimePermission("accessClassInPackage."+pkg)</code> * If this method is overridden, then * <code>super.checkPackageAccess</code> should be called * as the first line in the overridden method. * @param pkg the package name. * @exception SecurityException if the calling thread does not have * permission to access the specified package. * @exception NullPointerException if the package name argument is * @see java.lang.ClassLoader#loadClass(java.lang.String, boolean) * @see java.security.Security#getProperty getProperty * @see #checkPermission(java.security.Permission) checkPermission * Do we need to update our property array? // Using a snapshot of packageAccess -- don't care if static field // changes afterwards; array contents won't change. * Traverse the list of packages, check for any matches. break;
// No need to continue; only need to check this once * Throws a <code>SecurityException</code> if the * calling thread is not allowed to define classes in the package * specified by the argument. * This method is used by the <code>loadClass</code> method of some * This method first gets a list of restricted packages by * obtaining a comma-separated list from a call to * <code>java.security.Security.getProperty("package.definition")</code>, * and checks to see if <code>pkg</code> starts with or equals * any of the restricted packages. If it does, then * <code>checkPermission</code> gets called with the * <code>RuntimePermission("defineClassInPackage."+pkg)</code> * If this method is overridden, then * <code>super.checkPackageDefinition</code> should be called * as the first line in the overridden method. * @param pkg the package name. * @exception SecurityException if the calling thread does not have * permission to define classes in the specified package. * @see java.lang.ClassLoader#loadClass(java.lang.String, boolean) * @see java.security.Security#getProperty getProperty * @see #checkPermission(java.security.Permission) checkPermission * Do we need to update our property array? // Using a snapshot of packageDefinition -- don't care if static // field changes afterwards; array contents won't change. * Traverse the list of packages, check for any matches. break;
// No need to continue; only need to check this once * Throws a <code>SecurityException</code> if the * calling thread is not allowed to set the socket factory used by * <code>ServerSocket</code> or <code>Socket</code>, or the stream * handler factory used by <code>URL</code>. * This method calls <code>checkPermission</code> with the * <code>RuntimePermission("setFactory")</code> permission. * If you override this method, then you should make a call to * <code>super.checkSetFactory</code> * at the point the overridden method would normally throw an * @exception SecurityException if the calling thread does not have * permission to specify a socket factory or a stream * @see java.net.ServerSocket#setSocketFactory(java.net.SocketImplFactory) setSocketFactory * @see java.net.Socket#setSocketImplFactory(java.net.SocketImplFactory) setSocketImplFactory * @see java.net.URL#setURLStreamHandlerFactory(java.net.URLStreamHandlerFactory) setURLStreamHandlerFactory * @see #checkPermission(java.security.Permission) checkPermission * Throws a <code>SecurityException</code> if the * calling thread is not allowed to access members. * The default policy is to allow access to PUBLIC members, as well * as access to classes that have the same class loader as the caller. * In all other cases, this method calls <code>checkPermission</code> * with the <code>RuntimePermission("accessDeclaredMembers") * If this method is overridden, then a call to * <code>super.checkMemberAccess</code> cannot be made, * as the default implementation of <code>checkMemberAccess</code> * relies on the code being checked being at a stack depth of * @param clazz the class that reflection is to be performed on. * @param which type of access, PUBLIC or DECLARED. * @exception SecurityException if the caller does not have * permission to access members. * @exception NullPointerException if the <code>clazz</code> argument is * @see java.lang.reflect.Member * @see #checkPermission(java.security.Permission) checkPermission * stack depth of 4 should be the caller of one of the * methods in java.lang.Class that invoke checkMember * access. The stack should look like: * java.lang.Class.someReflectionAPI [2] * java.lang.Class.checkMemberAccess [1] * SecurityManager.checkMemberAccess [0] * Determines whether the permission with the specified permission target * name should be granted or denied. * <p> If the requested permission is allowed, this method returns * quietly. If denied, a SecurityException is raised. * <p> This method creates a <code>SecurityPermission</code> object for * the given permission target name and calls <code>checkPermission</code> * <p> See the documentation for * <code>{@link java.security.SecurityPermission}</code> for * a list of possible permission target names. * <p> If you override this method, then you should make a call to * <code>super.checkSecurityAccess</code> * at the point the overridden method would normally throw an * @param target the target name of the <code>SecurityPermission</code>. * @exception SecurityException if the calling thread does not have * permission for the requested access. * @exception NullPointerException if <code>target</code> is null. * @exception IllegalArgumentException if <code>target</code> is empty. * @see #checkPermission(java.security.Permission) checkPermission * Returns the thread group into which to instantiate any new * thread being created at the time this is being called. * By default, it returns the thread group of the current * thread. This should be overridden by a specific security * manager to return the appropriate thread group. * @return ThreadGroup that new threads are instantiated into * @see java.lang.ThreadGroup