library.policy file permissions
Java™ 2 security uses several policy files to determine the granted permission for each Java program.
For the list of available policy files that are supported by WebSphere® Application Server, see Java 2 security policy files.
The library.policy file is the template for shared libraries (Java library classes). Multiple enterprise applications can define and use shared libraries. Refer to Managing shared libraries for information on how to define and manage the shared libraries.
If the default permissions for a shared library (union of the permissions defined in the java.policy file, the app.policy file and the library.policy file) are enough, no action is required. The default library policy is picked up automatically. If a specific change is required to share a library in the cell, update the library.policy file.
Syntax errors in the policy files cause the application server to fail. Edit these policy files carefully.
To extract the policy file, use a command prompt to enter the following command using the appropriate variable values for your environment:The previous two lines were split onto two lines for illustrative purposes only.
node_name/library.policy c:/temp/test/library.policy]
node_name/library.policy /temp/test/library.policy]
node_name/library.policy /temp/test/library.policy]
Edit the extracted library.policy file with the Policy Tool. For more information, see Using PolicyTool to edit policy files for Java 2 security.
To check in the policy file, use a command prompt to enter the following command using the appropriate variable values for your environment:An updated library.policy is applied to shared libraries after the servers restart.
c:/temp/test/library.policy $obj
temp/test/library.policy $obj
temp/test/library.policy $obj
Example
The union of the permission that is contained in the java.policy file, the app.policy file, and the library.policy file are applied to the shared libraries. The library.policy file is managed by configuration and file replication services.
Changes made in the file are replicated to other nodes in the cell.
grant { };
grant { };
If the shared library in a cell requires permissions that are not defined as defaults in thejava.policy file, the app.policy file and the library.policy file, update the library.policy file. The missing permission causes the java.security.AccessControlException exception. The missing permission is listed in the exception data.
java.security.AccessControlException: access denied (java.io.FilePermission app_server_root/lib/mail-impl.jar read)The previous lines are split into two lines for illustrative purposes only. The app_server_root variable represents your installation directory.
java.security.AccessControlException: access denied (java.io.FilePermission
app_server_rootBase/lib/mail-impl.jar read)
The
previous lines are split into two lines for illustrative purposes
only.When a Java program receives this exception and adding this permission is justified, add a permission to the library.policy file.
grant { permission java.io.FilePermission "app_server_root/lib/mail-impl.jar", "read"; };The previous lines are split into two lines for illustrative purposes only. The app_server_root variable represents your installation directory.
grant codeBase "file:user_client_installed_location" { permission
java.io.FilePermission "app_server_rootBase/lib/mail-impl.jar", "read"; };
The previous lines are split into two lines for illustrative
purposes onlyTo decide whether to add a permission, refer to Access control exception for Java 2 security.
Restart the related Java processes for the changes in the library.policy file to become effective.