Naming roles
The J2EE role-based authorization concept has been extended to protect the WebSphere CosNaming service.
CosNaming security offers increased granularity of security control over CosNaming functions. CosNaming functions are available on CosNaming servers such as the WebSphere Application Server. They affect the content of the WebSphere Name Space. There are generally two ways in which client programs will result in CosNaming calls. The first is through the JNDI interfaces. The second is CORBA clients invoking CosNaming methods directly.
Four security roles are introduced: CosNamingRead, CosNamingWrite, CosNamingCreate, and CosNamingDelete. The name of the four roles are the same with WebSphere Advanced Edition Version 4.0.2. However, the roles now have authority level from low to high as follows...
- CosNamingRead. Users who have been assigned the CosNamingRead role will be allowed to do queries of the WebSphere Name Space, such as through the JNDI "lookup" method. The special-subject Everyone is the default policy for this role.
- CosNamingWrite. Users who have been assigned the CosNamingWrite role will be allowed to do write operations such as JNDI "bind", "rebind", or "unbind", plus CosNamingRead operations. The special-subject AllAuthenticated is the default policy for this role.
- CosNamingCreate. Users who have been assigned the CosNamingCreate role will be allowed to create new objects in the Name Space through such operations as JNDI "createSubcontext", plus CosNamingWrite operations. The special-subject AllAuthenticated is the default policy for this role.
- CosNamingDelete. And finally users who have been assigned CosNamingDelete role will be able to destroy objects in the Name Space, for example using the JNDI "destroySubcontext" method, as well as CosNamingCreate operations. The special-subject AllAuthenticated is the default policy for this role.
Users, groups, or the special subjects AllAuthenticated and Everyone can be added or removed to or from the Naming roles from the WebSphere web based administrative console at anytime. However, a server restart is required for the changes to take effect. A best practice is to map a group(s) or one of the special-subjects, rather than specific users, to Naming roles because it is more flexible and easier to administer in the long run. By mapping a group to an Naming role, adding or removing users to or from the group occurs outside of WebSphere and does not require a server restart for the change to take effect.
If a user is assigned a particular naming role and that user is a member of a group that has been assigned a different naming role, the user will be granted the most permissive access between the role he was assigned and the role his group was assigned. For example, assume that user MyUser has been assigned the CosNamingRead role. Also, assume that group MyGroup has been assigned the CosNamingCreate role. If MyUser is a member of MyGroup, MyUser will be assigned the CosNamingCreate role because he is a member of MyGroup. If MyUser were not a member of MyGroup, he would be assigned the CosNamingRead role.
The CosNaming authorization policy is only enforced when global security is enabled. When global security is enabled, attempts to do CosNaming operations without the proper role assignment will result in a org.omg.CORBA.NO_PERMISSION exception from the CosNaming Server.
In the previous release (Version 4.0.2) of the product, each CosNaming function is assigned to only one role. Therefore, users who have been assigned CosNamingCreate role will not be able to query the Name Space unless they have also been assigned CosNamingRead. In most cases a creator would need to be assigned three roles: CosNamingRead, CosNamingWrite, and CosNamingCreate. This has been changed in the release. The CosNamingRead and CosNamingWrite roles assignment for the creator example in above have been included in CosNamingCreate role. In most of the cases, WAS administrators do not have to change the roles assignment for every user or group when they move to this release from previous one.
Although the ability exist to greatly restrict access to the Name space by changing the default policy, doing so may result in unexpected org.omg.CORBA.NO_PERMISSION exceptions at run time. Typically, J2EE applications access the Name space and the identity they use is that of the user that authenticated to WAS when they access the J2EE application. Unless the J2EE application provider clearly communicates the expected Naming roles, care should be taken when changing the default naming authorization policy.