Java 2 security is a programming model that is very pervasive and
has a huge impact on application development.
Before you begin
It is disabled by default, but is enabled
automatically when global security is enabled. However, Java 2 security is
orthogonal to Java 2 Platform, Enterprise Edition (J2EE) role-based security;
you can disable or enable it independently of Global Security.
However,
it does provide an extra level of access control protection on top of the
J2EE role-based authorization. It particularly addresses the protection of
system resources and application programming interfaces (API). Administrators
need to consider the benefits against the risks of disabling Java 2 security.
The
following recommendations are provided to help enable Java 2 security in a
test or production environment:
- Make sure the application is developed with the Java 2 security programming
model. Developers have to know whether or not the APIs that are used in the
applications are protected by Java 2 security. It is very important that the
required permissions for the APIs used are declared in the policy file (was.policy),
or the application fails to run when Java 2 security is enabled. Developers
can reference the Web site for Development Kit APIs that are protected by
Java 2 security. See the Programming model and decisions section of the Security: Resources for learning topic to visit this Web
site.
- Make sure that migrated applications from previous releases are given
the required permissions. Because Java 2 security is not supported or partially
supported in previous WebSphere Application Server releases, applications
developed prior to Version 5 most likely are not using the Java 2 security
programming model. No easy way to find out all the required permissions for
the application is available. The following are activities you can perform
to determine the extra permissions that are required by an application:
- Code review and code inspection
- Application documentation review
- Sandbox testing of migrated enterprise applications with Java 2 security
enabled in a preproduction environment. Enable tracing in WebSphere Java 2
security manager to help determine the missing permissions in the application
policy file. The trace specification is: com.ibm.ws.security.core.SecurityManager=all=enabled.
- Use the com.ibm.websphere.java2secman.norethrow system property to aid
debugging. Do not use this property in a production environment.
The default permission set for applications
is the recommended permission set that is defined in the J2EE 1.3 Specification.
The default is declared in the app_server_root/profiles/profile_name/config/cells/cell_name/nodes/node_name/app.policy policy file with permissions
defined in the Development Kit (JAVA_HOME/jre/lib/security/java.policy)
policy file that grant permissions to everyone. However, applications are
denied permissions that are declared in the profiles/profile_name/config/cells/cell_name/filter.policy file.
Permissions that are declared in the filter.policy file are filtered
for applications during the permission check.
Define the
required permissions for an application in a was.policy file and
embed the was.policy file in the application enterprise archive (EAR)
file as YOURAPP.ear/META-INF/was.policy, see Configuring Java 2 security policy files for details.
The following
steps describe how to enforce Java 2 security on the cell level for WebSphere
Application Server Network Deployment and the server level for WebSphere Application
Server and WebSphere Application Server Express:
What to do next
You can enforce Java 2 security
on the server level for WebSphere Application Server Network Deployment by
completing the following steps:
- Click Servers > Application servers > server_name.
- Under Security, click Server security.
- Under Additional properties, click Server-level security.
- Select the Enforce Java 2 security option.
- Click OK or Apply.
- Click Save to save the changes.
- Restart the server for the changes to take effect.
The Java 2 security manager is enhanced to dump the Java 2 security
permissions that are granted to all classes on the call stack when an application
is denied access to a resource. The java.security.AccessControlException exception
is created. However, this tracing capability is disabled by default. You can
enable this capability by specifying the server trace service with the
com.ibm.ws.security.core.SecurityManager=all=enabled trace
specification. When the exception is created, the trace dump provides hints
to determine whether the application is missing permissions or the product
runtime code or the third-party libraries that are used are not properly marked
as
privileged when accessing Java 2 security-protected resources.
See the
Security Problem
Determination Guide for details.