Java 2 security policy files

 

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The J2EE V1.3 specification has a well-defined programming model of responsibilities between the container providers and the application code. Using Java 2 security manager to help enforce this programming model is recommended. Certain operations are not supported in the application code because such operations interfere with the behavior and operation of the containers. The Java 2 security manager is used in the product to enforce responsibilities of the container and the application code.

WebSphere Application Server provides support for policy file management. A number of policy files in the product are either static or dynamic. Dynamic policy is a template of permissions for a particular type of resource. No relative code base is defined in the dynamic policy template. The code base is dynamically calculated from the deployment and run-time data.

 

Static policy files

Policy file Location
java.policy install_root/java/jre/lib/security/java.policy.

Default permissions granted to all classes. The policy of this file applies to all the processes launched by WebSphere Application Server.

server.policy install_root/profiles/profile/properties/server.policy.

Default permissions granted to all the product servers.

client.policy install_root/profiles/profile/properties/client.policy.

Default permissions for all of the product client containers and applets on a node.

The static policy files are not managed by configuration and file replication services. Changes made in these files are local and are not replicated to other nodes in the Network Deployment cell.

 

Dynamic policy files

Policy file Location
spi.policy

install_root/profiles/profile/config/cells/cell/nodes/node/spi.policy

This template is for the Service Provider Interface (SPI) or the third-party resources that are embedded in the product. Examples of SPI are the Java Message Service (JMS) in MQ Series and JDBC drivers. The code base for the embedded resources are dynamically determined from the configuration (resources.xml file) and run-time data, and permissions that are defined in the spi.policy files are automatically applied to these resources and JAR files specified in the class path of a ResourceAdapter. The default permission of the spi.policy file is java.security.AllPermissions.

library.policy

install_root/profiles/profile/config/cells/cell/nodes/node/library.policy

This template is for the library (Java library classes). We can define a shared library to use in multiple product applications. The default permission of the library.policy is empty.

app.policy

install_root/profiles/profile/config/cells/cell/nodes/node/app.policy

The app.policy file defines the default permissions that are granted to all the enterprise applications running on node in cell.

was.policy

install_root/config/cells/cell/applications/ear_file_name/deployments/appname/META-INF/was.policy

This template is for application-specific permissions. The was.policy file is embedded in the EAR file.

ra.xml rar_file_name/META-INF/was.policy.RAR.

This file can have a permission specification that is defined in the ra.xml file. The ra.xml file is embedded in the RAR file.

Note: Grant entries that are specified in the app.policy and was.policy files must have a code base defined. If grant entries are specified without a code base, the policy files are not loaded properly and the application can fail. If the intent is to grant the permissions to all applications, use file:${application} as a code base in the grant entry.

 

Syntax of the policy file

A policy file contains several policy entries. The following example depicts each policy entry format:

grant [codebase <Codebase>] {
permission <Permission>;
permission <Permission>;
permission <Permission>;
};

<CodeBase>: A URL.
For example, "file:${java.home}/lib/tools.jar"
When [codebase <Codebase>] is not specified, listed
permissions are applied to everything.
If URL ends with a JAR file name, only the classes in the
JAR file belong to the codebase.
If URL ends with "/", only the class files in the specified
directory belong to the codebase.
If URL ends with "*", all JAR and class files in the specified
directory belong to the codebase.
If URL ends with "-", all JAR and class files in the specified
directory and its subdirectories belong to the codebase.
<Permissions>: Consists from
Permission Type : class name of the permission
Target Name : name specifying the target
Actions : actions allowed on target
For example,
java.io.FilePermission "/tmp/xxx", "read,write"

Refer to developer kit specifications for the details of each permission.

 

Syntax of dynamic policy

We can define permissions for specific types of resources in dynamic policy files for an enterprise application. This action is achieved by using product-reserved symbols. The reserved symbol scope depends on where it is defined. If you define the permissions in app.policy, the symbol applies to all the resources on all of the enterprise applications that run on node. If you define the permissions in the META-INF/was.policy file, the symbol applies only to the specific enterprise application. Valid symbols for the code base are listed in the following table:

Symbol Meaning
file:${application} Permissions apply to all resources within the application
file:${jars} Permissions apply to all utility Java archive (JAR) files within the application
file:${ejbComponent} Permissions apply to Enterprise JavaBeans (EJB) resources within the application
file:${webComponent} Permissions apply to Web resources within the application
file:${connectorComponent} Permissions apply to connector resources within the application

Other than these entries specified by the code base symbols, one can specify the module name for a granular setting. For example:

grant codeBase "file:DefaultWebApplication.war" {
permission java.security.SecurityPermission "printIdentity";
};

grant codeBase "file:IncCMP11.jar" {
permission java.io.FilePermission "${user.install.root}${/}bin${/}DefaultDB${/}-", "read,write,delete";
};

Use a relative code base only in the META-INF/was.policy file.

Several product-reserved symbols are defined to associate the permission lists to a specific type of resources.

Symbol Meaning
file:${application} Permissions apply to all resources within the application
file:${jars} Permissions apply to all utility JAR files within the application
file:${ejbComponent} Permissions apply to enterprise beans resources within the application
file:${webComponent} Permissions apply to Web resources within the application
file:${connectorComponent} Permissions apply to connector resources both within the application and in stand-alone connector resources.
Five embedded symbols are provided to specify the path and the name for the java.io.FilePermission permission. These symbols enable flexible permission specification. The absolute file path is fixed after the installation of the application.

Symbol Meaning
${app.installed.path} Path where the application is installed
${was.module.path} Path where the module is installed
${current.cell.name} Current cell name
${current.node.name} Current node name
${current.server.name} Current server name

Note: Do not use the ${was.module.path} in the ${application} entry.

Carefully determine where to add a new permission. An incorrectly specified permission causes an AccessControlException exception. Because dynamic policy resolves the code base at run time, determining which policy file has a problem is difficult. Add a permission only to the necessary resources. For example, use ${ejbcomponent}, and etc instead of ${application}, and update the was.policy file instead of app.policy, if possible.

 

Static policy filtering

Limited static policy filtering support exists. If app.policy and the was.policy file have permissions that are defined in the filter.policy file with the keyword, filterMask, the run time removes the permissions from the applications and an audit message is logged. However, if the permissions that are defined in the app.policy and the was.policy files are compound permissions, for example, java.security.AllPermission, the permission is not removed, but a warning message is written to the log file. The policy filtering only supports Developer Kit permissions, (the permissions package name begins with java or javax).

Run-time policy filtering support is provided to force stricter filtering. If app.policy and the was.policy file have permissions that are defined in the filter.policy file with the keyword, runtimeFilterMask, the run time removes the permissions from the applications no matter what permissions are granted to the application. For example, even if a was.policy file has the java.security.AllPermission permission granted to one of its modules, specified permissions such as runtimeFilterMask are removed from the granted permission during run time.

If the Issue Permission Warning flag in the Global Security panel is enabled and if app.policy and the was.policy file contain custom permissions (non-Developer Kit permissions, where the permissions package name begins with java or javax), a warning message logs. The permission is not removed. If the AllPermission permission is listed in app.policy and the was.policy file, a warning message logs.

 

Policy file editing

Using the policy tool provided by the Developer Kit (install_root/java/jre/bin/policytool), to edit the previous policy files is recommended. For Network Deployment, extract the policy files from the repository before editing. After the policy file is extracted, use the policy tool to edit the file. Check the modified policy files into the repository and synchronize them with other nodes.

If syntax errors exist in the policy files, the enterprise application or the server process might fail to start. Be cautious when editing these policy files. For example, if a policy has a trailing space in the policy permission target name, the policy fails to parse the permission properly in the IBM Developer Kit, Java Technology Edition V1.4.2. In the following example, note the space before the last quote: * \"*\" "

grant {
permission javax.security.auth.PrivateCredentialPermission
"javax.resource.spi.security.PasswordCredential * \"*\" ","read";
};

If the permission is in a policy file loaded by the IBM Developer Kit, Java Technology Edition V1.4.2 policy tool, the following message might display:

Errors have occurred while opening the policy configuration.
View the warning log for more information. or the following message might display in warning log:

Warning: Invalid argument(s) for constructor:
javax.security.auth.PrivateCredentialPermission.

To fix this problem, edit the permission and remove the trailing space. When the trailing space is removed, the permission loads properly. The following code sample shows the corrected permission:

grant {
permission javax.security.auth.PrivateCredentialPermission
"javax.resource.spi.security.PasswordCredential * \"*\"","read";
}

 

Troubleshoot

To debug the dynamic policy, choose one of three ways to generate the detail report of the AccessControlException exception.

  • Trace (Configured by RAS trace). Enables traces with the trace specification: Attention: The following command is one continuous line

    com.ibm.ws.security.policy.*=all=enabled:
    com.ibm.ws.security.core.SecurityManager=all=enabled

  • Trace (Configured by property). Specifies a Java java.security.debug property . Valid values for the java.security.debug property are as follows:

    • Access. Print all debug information including required permission, code, stack, and code base location.

    • Stack. Print debug information including, required permission, code, and stack.

    • Failure. Print debug information including required permission and code.

  • ffdc. Enable ffdc, modify the ffdcRun.properties file by changing Level=4and LAE=true. Look for an Access Violation keyword in the log file.


 

Related Tasks

Configuring Java 2 security
Using PolicyTool to edit policy files

 

See Also


Java 2 security