(ZOS) System Authorization Facility for role-based authorization

There are three choices we have when assigning roles: (1) WebSphere Application Server authorization, in which authorization management is performed within the WebSphere Administration using the Security role to user/group mapping panel of the administrative console. (2) The System Authorization Facility (SAF) for role-based authorization (WebSphere Authorization Facility for z/OS only option), which uses SAF authorization for Java 2 Platform Enterprise Edition (J2EE) roles. (3) External Authorization Provider using the pluggable JACC interfaces. When WAS is configured to use SAF Authorization, the authorization management is performed using SAF management facilities and the user or group to J2EE role Management within WebSphere Administration is ignored. SAF class of EJBROLE is used (for example, using the RACF EJBROLE profile) to control access by a client to J2EE roles in EJB and web applications, including the WAS administrative console application.

Important considerations when using SAF authorization: When we select SAF for authorization, there are several functional implications to subsequent authorization operations needed to consider:

• If SAF authorization is selected on the administrative console, it overrides any other authorization choice (such as, ISAM authorization). See Summary of controls for more information.

• When SAF authorization is enabled, authorization on any level is always performed by the operating system's security manager (RACF or equivalent product). That is, users need to be authenticated with a security manager (RACF) user ID or a SAF mapping module needs to be used.. See System Authorization Facility considerations for the operating system and application levels for more information.

• When SAF authorization is selected during systems customization, administrative EJBROLE profiles for all administrative roles are defined by the RACF jobs generated using the customization dialogs, and SAF authorization can be used as an authorization mechanism for all user registries. See z/OS Controlling access to console users when using a Local OS Registry for more information.

• When configuring SAF authorization, property, com.ibm.security.SAF.authorization is set to true and SAF EJBROLE profiles are used to control access to administrative roles. See Authorizing access to administrative roles for more information about authorizing access to administrative roles.

• When SAF authorization is enabled, any values in the console users and console groups are ignored. The Map security roles to users/groups functional panel in the administrative console is ignored. See Administrative roles and naming service authorization for more information.
• Everyone and All Authenticated are ignored since they are managed in RACF. See System Authorization Facility considerations for the operating system and application levels as well as Security role to user or group mapping for more information.

• When SAF authorization is enabled, the SAF EJBROLE profiles are used to control access to CosNaming functions. During security domain setup in the customization dialog, the CosNaming roles are defined by customization jobs. See Special considerations for controlling access to naming roles using SAF authorization for more information on CosNaming functions and SAF authorization as well as referencing Administrative roles and naming service authorization.

• When SAF authorization is enabled, SAF EJBROLE profiles are used to authorize J2EE roles. For non-local operating system registries, identity mapping must be in place to map WAS identities to SAF identities. See z/OS Controlling access to console users when using a Local OS Registry for more information
• SAF authorization for J2EE roles is a task that is independent of the application deployment process. See Assigning users and groups to roles for more information.

• The EJBROLE class should be RACLISTed. If the EJBROLE class is not RACLISTed, we must restart the application server to pick up changes made to profiles in the EJBROLE class.

• The Servlet 3.1 specification newly defines the role name ** which grants access for all authenticated users. By default, the authorization decision is made by the SAF.

• The com.ibm.websphere.security.delegateStarStarRoleAuthorization custom property defines whether the security code grants the access to all authenticated users when the role name is **.
  • true - The security code grants the access without interacting the pluggable authorization table.
  • false - The security code delegates the decision to the pluggable authorization table. This is the default value.

When we use SAF authorization, to make sure any changes in SAF to a user or group membership become effective immediately, call the purgeUserFromAuthCache SecurityAdmin mbean method for the modified user. Otherwise, the changes become effective when the cache is refreshed on a periodic basis. As an alternative, we can restart the server.

When SAF authorization is enabled, SAF EJBROLE profiles are used to authorize Java EE roles. For non-local operating system registries, identity mapping must be in place to map WAS identities to SAF identities.

To enable SAF authorization, see z/OS System Authorization Facility authorization for more information.

Define EJBROLES belongs to the application deployment process. If the user ID has at least READ access to the defined EJBROLE profile that corresponds to the Java EE role defined by the application, the user ID is considered to be in Role. (Do not be confused by the name EJBROLE. It is used for Java EE roles in both enterprise beans and Web applications.)

When an application deployer uses a role in the deployment descriptor of a component, the role name must be identical to the name of an EJBROLE profile. A security administrator defines EJBROLE profiles and permits SAF users or groups to the profiles. In order to be considered as eligible for a role, a user must have read access to the EJBROLE profile or must be connected to a SAF group that has read access.

The specification of a SAF profile prefix (previously referred to as a z/OS security domain) affects the specific EJBROLE profiles used by WAS for z/OS system resources when SAF authorization is chosen. When a SAF prefix is defined, the Java EE application EJBROLE profiles for the WAS for z/OS runtime are prefixed with the value of this property. This enables us to deploy the same application on different cells in the same sysplex, but have different user to role mappings if desired.

For example, the application has two Java EE role names: juniorTellers and seniorTellers. These are mixed case roles. In your SAF registry, we have an MVS group called JTELLER and STELLER and a MVS user ID called BANKADM. The JTELLER group is required to access to the juniorTellers role, and the STELLER group is required to access the seniorTellers role. The BANKADM user ID is required to access both roles.

We have two cells, both defined to use a SAF profile prefix. The prefixes are PRODCELL and TESTCELL, respectively. The TEST1 user ID should have access to both roles, but only in the test environment TESTCELL.

If we wanted to deploy the same application in both cells, we must define distinct profiles using a RACF (or equivalent security subsystem) as follows.

If RACF is used as our security server, enable this by issuing the following commands:

/* the EJBROLE class must be active, this step is done by the customization dialogs  */
SETROPTS CLASSACT(EJBROLE)

/* first define the roles in RACF */
RDEFINE EJBROLE PRODCELL.juniorTellers UACC(NONE)
RDEFINE EJBROLE PRODCELL.seniorTellers UACC(NONE)

RDEFINE EJBROLE TESTCELL.juniorTellers UACC(NONE)
RDEFINE EJBROLE TESTCELL.seniorTellers UACC(NONE)

/* permit the appropriate users and groups to the various roles */
PERMIT PRODCELL.juniorTellers CLASS(EJBROLE)  ID(JTELLER BANKADM) ACCESS(READ)
PERMIT PRODCELL.seniorTellers CLASS(EJBROLE)  ID(STELLER BANKADM) ACCESS(READ)

PERMIT TESTCELL.juniorTellers CLASS(EJBROLE)  ID(TEST1) ACCESS(READ)
PERMIT TESTCELL.seniorTellers CLASS(EJBROLE)  ID(TEST1) ACCESS(READ)

/* refresh the EJBROLE class in RACF *
SETROPTS RACLIST(EJBROLE) REFRESH"     

Grouping EJBROLES (GEJBROLE)

The SAF interface also supports a grouping class for the EJBROLE class. This grouping class is called GEJBROLE. It is particularly useful when we have a need to give access to the same users or groups for several roles.

The GEJBROLE grouping class provides a capability not natively available in other Java EE servers. Using the Java EE security model, if there are several components or applications that use different role names for similar functions, such as Hire, Promote, or GrantPayraise for managerial functions, there are several options:

• Adjust the application deployment descriptors so that they conform to the roles already defined in the enterprise, such as managers. This process is time consuming and error prone especially because it might require a readjustment of the deployment descriptor each time the application is changed or reinstalled.

• Define the EJBROLE profiles for each of the roles required by the application. Then, permit users and groups to access these roles. This process might be extensive for the administrator because the same users and groups might have permissions for several different profiles with similar meanings.

• Use the grouping class to avoid the worst issues with the other two options. We must still define EJBROLE profiles for each of the roles required by the application. Instead of permitting all of the same users and groups to use the new profiles, create a profile, such as supervisors, in the grouping class and add all of the new EJBROLE profiles to it. We can give permission in one place to every user and group that needs access to these roles, such as the supervisors profile. We can further avoid administrative work by adding the existing EJBROLE profile (Managers) to the grouping class profile (Supervisors).

Considerations when implementing GEJBROLES:

• Plan organizational role profiles in the RACF class GEJBROLEs.

• Create the access list by permitting user groups to the GEJBROLE profiles, then add roles to the GEJBROLE profiles.
• A GEJBROLE with only one EJBROLE is OK.
• Do not use a mixture of EJBROLE and GEJBROLE for permitting users to roles.

• If possible, permit users to GEJBROLE profiles only.
• Generally use GEJBROLE in preference to EJBROLE.

Subtopics

• System Authorization Facility user registries
  System Authorization Facility (SAF) user registries are used for several purposes in WAS for z/OS.

• Special considerations for controlling access to naming roles using SAF authorization
  There are special considerations in WAS for controlling access to naming roles.

• System Authorization Facility (SAF) delegation
  System Authorization Facility (SAF) delegation minimizes the need to store user Ids and passwords in many locations in the configuration.

Related:

Authorization technology