198 lines
7.9 KiB
Java
198 lines
7.9 KiB
Java
/* AccessController.java --- Access control context and permission checker
|
|
Copyright (C) 2001, 2004 Free Software Foundation, Inc.
|
|
|
|
This file is part of GNU Classpath.
|
|
|
|
GNU Classpath is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2, or (at your option)
|
|
any later version.
|
|
|
|
GNU Classpath is distributed in the hope that it will be useful, but
|
|
WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with GNU Classpath; see the file COPYING. If not, write to the
|
|
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
|
02111-1307 USA.
|
|
|
|
Linking this library statically or dynamically with other modules is
|
|
making a combined work based on this library. Thus, the terms and
|
|
conditions of the GNU General Public License cover the whole
|
|
combination.
|
|
|
|
As a special exception, the copyright holders of this library give you
|
|
permission to link this library with independent modules to produce an
|
|
executable, regardless of the license terms of these independent
|
|
modules, and to copy and distribute the resulting executable under
|
|
terms of your choice, provided that you also meet, for each linked
|
|
independent module, the terms and conditions of the license of that
|
|
module. An independent module is a module which is not derived from
|
|
or based on this library. If you modify this library, you may extend
|
|
this exception to your version of the library, but you are not
|
|
obligated to do so. If you do not wish to do so, delete this
|
|
exception statement from your version. */
|
|
|
|
package java.security;
|
|
|
|
/**
|
|
* Access control context and permission checker.
|
|
* Can check permissions in the access control context of the current thread
|
|
* through the <code>checkPermission()</code> method.
|
|
* Manipulates the access control context for code that needs to be executed
|
|
* the protection domain of the calling class (by explicitly ignoring the
|
|
* context of the calling code) in the <code>doPrivileged()</code> methods.
|
|
* And provides a <code>getContext()</code> method which gives the access
|
|
* control context of the current thread that can be used for checking
|
|
* permissions at a later time and/or in another thread.
|
|
* <p>
|
|
* XXX - Mostly a stub implementation at the moment. Needs native support
|
|
* from the VM to function correctly. XXX - Do not forget to think about
|
|
* how to handle <code>java.lang.reflect.Method.invoke()</code> on the
|
|
* <code>doPrivileged()</code> methods.
|
|
*
|
|
* @author Mark Wielaard (mark@klomp.org)
|
|
* @since 1.2
|
|
*/
|
|
public final class AccessController
|
|
{
|
|
/**
|
|
* This class only has static methods so there is no public contructor.
|
|
*/
|
|
private AccessController()
|
|
{
|
|
}
|
|
|
|
/**
|
|
* Checks wether the access control context of the current thread allows
|
|
* the given Permission. Throws an <code>AccessControlException</code>
|
|
* when the permission is not allowed in the current context. Otherwise
|
|
* returns silently without throwing an exception.
|
|
*
|
|
* @param perm the permission to be checked.
|
|
* @exception AccessControlException thrown if the current context does not
|
|
* allow the given permission.
|
|
*/
|
|
public static void checkPermission(Permission perm)
|
|
throws AccessControlException
|
|
{
|
|
getContext().checkPermission(perm);
|
|
}
|
|
|
|
/**
|
|
* Calls the <code>run()</code> method of the given action with as
|
|
* (initial) access control context only the protection domain of the
|
|
* calling class. Calls to <code>checkPermission()</code> in the
|
|
* <code>run()</code> method ignore all earlier protection domains of
|
|
* classes in the call chain. Note that the protection domains of classes
|
|
* called by the code in the <code>run()</code> method are not ignored.
|
|
*
|
|
* @param action the <code>PrivilegedAction</code> whose <code>run()</code>
|
|
* should be be called.
|
|
* @return the result of the <code>action.run()</code> method.
|
|
*/
|
|
public static Object doPrivileged(PrivilegedAction action)
|
|
{
|
|
return action.run();
|
|
}
|
|
|
|
/**
|
|
* Calls the <code>run()</code> method of the given action with as
|
|
* (initial) access control context the given context combined with the
|
|
* protection domain of the calling class. Calls to
|
|
* <code>checkPermission()</code> in the <code>run()</code> method ignore
|
|
* all earlier protection domains of classes in the call chain, but add
|
|
* checks for the protection domains given in the supplied context.
|
|
*
|
|
* @param action the <code>PrivilegedAction</code> whose <code>run()</code>
|
|
* should be be called.
|
|
* @param context the <code>AccessControlContext</code> whose protection
|
|
* domains should be added to the protection domain of the calling class.
|
|
* @return the result of the <code>action.run()</code> method.
|
|
*/
|
|
public static Object doPrivileged(PrivilegedAction action,
|
|
AccessControlContext context)
|
|
{
|
|
return action.run();
|
|
}
|
|
|
|
/**
|
|
* Calls the <code>run()</code> method of the given action with as
|
|
* (initial) access control context only the protection domain of the
|
|
* calling class. Calls to <code>checkPermission()</code> in the
|
|
* <code>run()</code> method ignore all earlier protection domains of
|
|
* classes in the call chain. Note that the protection domains of classes
|
|
* called by the code in the <code>run()</code> method are not ignored.
|
|
* If the <code>run()</code> method throws an exception then this method
|
|
* will wrap that exception in an <code>PrivilegedActionException</code>.
|
|
*
|
|
* @param action the <code>PrivilegedExceptionAction</code> whose
|
|
* <code>run()</code> should be be called.
|
|
* @return the result of the <code>action.run()</code> method.
|
|
* @exception PrivilegedActionException wrapped around any exception that
|
|
* is thrown in the <code>run()</code> method.
|
|
*/
|
|
public static Object doPrivileged(PrivilegedExceptionAction action)
|
|
throws PrivilegedActionException
|
|
{
|
|
|
|
try
|
|
{
|
|
return action.run();
|
|
}
|
|
catch (Exception e)
|
|
{
|
|
throw new PrivilegedActionException(e);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Calls the <code>run()</code> method of the given action with as
|
|
* (initial) access control context the given context combined with the
|
|
* protection domain of the calling class. Calls to
|
|
* <code>checkPermission()</code> in the <code>run()</code> method ignore
|
|
* all earlier protection domains of classes in the call chain, but add
|
|
* checks for the protection domains given in the supplied context.
|
|
* If the <code>run()</code> method throws an exception then this method
|
|
* will wrap that exception in an <code>PrivilegedActionException</code>.
|
|
*
|
|
* @param action the <code>PrivilegedExceptionAction</code> whose
|
|
* <code>run()</code> should be be called.
|
|
* @param context the <code>AccessControlContext</code> whose protection
|
|
* domains should be added to the protection domain of the calling class.
|
|
* @return the result of the <code>action.run()</code> method.
|
|
* @exception PrivilegedActionException wrapped around any exception that
|
|
* is thrown in the <code>run()</code> method.
|
|
*/
|
|
public static Object doPrivileged(PrivilegedExceptionAction action,
|
|
AccessControlContext context)
|
|
throws PrivilegedActionException
|
|
{
|
|
|
|
try
|
|
{
|
|
return action.run();
|
|
}
|
|
catch (Exception e)
|
|
{
|
|
throw new PrivilegedActionException(e);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Returns the complete access control context of the current thread.
|
|
* <p>
|
|
* XXX - Should this include all the protection domains in the call chain
|
|
* or only the domains till the last <code>doPrivileged()</code> call?
|
|
* <p>
|
|
* XXX - needs native support. Currently returns an empty context.
|
|
*/
|
|
public static AccessControlContext getContext()
|
|
{
|
|
// For now just return an new empty context
|
|
return new AccessControlContext(new ProtectionDomain[0]);
|
|
}
|
|
}
|