org.elasticsearch

Class SecureSM

java.lang.Object

java.lang.SecurityManager

org.elasticsearch.SecureSM

public class SecureSM
extends SecurityManager

Extension of SecurityManager that works around a few design flaws in Java Security.

There are a few major problems that require custom SecurityManager logic to fix:

• exitVM permission is implicitly granted to all code by the default Policy implementation. For a server app, this is not wanted.
• ThreadGroups are not enforced by default, instead only system threads are protected out of box by modifyThread/modifyThreadGroup. Applications are encouraged to override the logic here to implement a stricter policy.
• System threads are not even really protected, because if the system uses ThreadPools, modifyThread is abused by its shutdown checks. This means a thread must have modifyThread to even terminate its own pool, leaving system threads unprotected.

This class throws exception on exitVM calls, and provides a whitelist where calls from exit are allowed.

Additionally it enforces threadgroup security with the following rules:

• modifyThread and modifyThreadGroup are required for any thread access checks: with these permissions, access is granted as long as the thread group is the same or an ancestor (sourceGroup.parentOf(targetGroup) == true).
• code without these permissions can do very little, except to interrupt itself. It may not even create new threads.
• very special cases (like test runners) that have ThreadPermission can violate threadgroup security rules.

If java security debugging (java.security.debug) is enabled, and this SecurityManager is installed, it will emit additional debugging information when threadgroup access checks fail.

See Also:

SecurityManager.checkAccess(Thread), SecurityManager.checkAccess(ThreadGroup), http://cs.oswego.edu/pipermail/concurrency-interest/2009-August/006508.html

Field Summary

Fields inherited from class java.lang.SecurityManager

inCheck

Constructor Summary

Constructors

Constructor and Description
SecureSM() Creates a new security manager where no packages can exit nor halt the virtual machine.
SecureSM(String[] packagesThatCanExit) Creates a new security manager with the specified list of packages being the only packages that can exit or halt the virtual machine.

Method Summary

Methods

Modifier and Type	Method and Description
void	checkAccess(Thread t)
void	checkAccess(ThreadGroup g)
void	checkExit(int status)
protected void	checkThreadAccess(Thread t)
protected void	checkThreadGroupAccess(ThreadGroup g)
static SecureSM	createTestSecureSM() Creates a new security manager with a standard set of test packages being the only packages that can exit or halt the virtual machine.
protected void	innerCheckExit(int status) The "Uwe Schindler" algorithm.

Methods inherited from class java.lang.SecurityManager

checkAccept, checkAwtEventQueueAccess, checkConnect, checkConnect, checkCreateClassLoader, checkDelete, checkExec, checkLink, checkListen, checkMemberAccess, checkMulticast, checkMulticast, checkPackageAccess, checkPackageDefinition, checkPermission, checkPermission, checkPrintJobAccess, checkPropertiesAccess, checkPropertyAccess, checkRead, checkRead, checkRead, checkSecurityAccess, checkSetFactory, checkSystemClipboardAccess, checkTopLevelWindow, checkWrite, checkWrite, classDepth, classLoaderDepth, currentClassLoader, currentLoadedClass, getClassContext, getInCheck, getSecurityContext, getThreadGroup, inClass, inClassLoader

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SecureSM

public SecureSM()

Creates a new security manager where no packages can exit nor halt the virtual machine.

SecureSM

public SecureSM(String[] packagesThatCanExit)

Creates a new security manager with the specified list of packages being the only packages that can exit or halt the virtual machine.

Parameters:

packagesThatCanExit - the list of packages that can exit or halt the virtual machine

Method Detail

createTestSecureSM

public static SecureSM createTestSecureSM()

Creates a new security manager with a standard set of test packages being the only packages that can exit or halt the virtual machine. The packages that can exit are

org.apache.maven.surefire.booter. com.carrotsearch.ant.tasks.junit4. org.eclipse.internal.junit.runner. com.intellij.rt.execution.junit.

Returns:

an instance of SecureSM where test packages can halt or exit the virtual machine

checkAccess

public void checkAccess(Thread t)

Overrides:

checkAccess in class SecurityManager

checkAccess

public void checkAccess(ThreadGroup g)

Overrides:

checkAccess in class SecurityManager

checkThreadAccess

protected void checkThreadAccess(Thread t)

checkThreadGroupAccess

protected void checkThreadGroupAccess(ThreadGroup g)

checkExit

public void checkExit(int status)

Overrides:

checkExit in class SecurityManager

innerCheckExit

protected void innerCheckExit(int status)

The "Uwe Schindler" algorithm.