J2EE agents can protect a variety of hosted J2EE applications, which can in turn require policy implementation that varies greatly from application to application. The security infrastructure of J2EE provides declarative as well as programmatic security that is platform-independent and is supported by all the J2EE-compliant deployment containers. For details on how to use the declarative and programmatic security of the J2EE platform, refer to J2EE documentation, available at http://java.sun.com/j2ee
The way J2EE agents are used has not changed significantly in the 2.2 release. The agents perform more effectively and efficiently in this release, but the basic functions are the same.
J2EE agents help enable role-to-principal mapping for protected J2EE applications with Access Manager principals. Thus at runtime, when a J2EE policy is evaluated, it is done against the information available in Access Manager. Using this functionality, administrators can configure their hosted J2EE applications to be protected by the agent, which provides real security services and also other key features such as single sign-on. Apart from enabling the J2EE security for hosted applications, the J2EE agents also provide complete support for Access Manager based URL policies for enforcing access control over web resources hosted in the deployment container.
The following examples demonstrate how the J2EE agents can be put to use:
Consider a web-based application that facilitates the auction of various kinds of merchandise between interested parties. A simple implementation for such an application will require the users to be in one of three abstract roles, namely Buyer, Seller, or Administrator. Buyers in this application will have access to web pages that display the listed auction items, whereas the Sellers may have access to web pages that allow them to list their merchandise for new auctions. The Administrators may have access to yet another set of web pages that allow them to finalize or cancel existing auctions in whatever state they may be in. Using the deployment descriptors, the application developer can express this intent by protecting such components using abstract security role names. These abstract role names in turn can be mapped to real principals in a J2EE agent. For example, the role Buyer may be mapped to an Access Manager role called Employee, the role Seller to an Access Manager role called Vendor, and the role Administrator to an Access Manager role called Admin. The abstract role names used by the application developer can be used to protect the necessary web pages and any specialized Enterprise JavaBeans (EJB) components from unauthorized access by using declarative as well as programmatic security. Once this application is deployed and configured, the agent will ensure that only the authorized personnel get access to these protected resources. For example, access to the pages meant for Sellers to list their merchandise for auctions will be granted to user Deepak only if this user belongs to the Access Manager role called Vendor. Similarly, users Scott and Gina can place bids on this listed item only if they belong to the role called Buyer. Once the auction period expires, the auction can be finalized by user Krishnendu only if he is in the role called Admin.
A web-based commerce application may have a variety of specialized EJB components that offer a spectrum of services to clients. For instance, there could be a specialized component that enables the creation of purchase orders. Similarly, there could be a specialized component that allows the approval of purchase orders. While such components provide the basic business services for the application to function, the very nature of tasks that they accomplish requires a security policy to enforce appropriate use of such services. Using the deployment descriptors, the application vendor or developer can express this intent by protecting such components using abstract security role names. For example, a developer can create a role called Buyer to protect the component that allows the creation of a purchase order and a role called Approver to protect the component that enables the approval of a purchase order. While these roles convey the intent of an application developer to enforce such security policies, they will not be useful unless these abstract role names are mapped to real life principals such as actual users or actual roles that reside in Access Manager. The J2EE agent enables the container to enforce such a runtime linkage of abstract security roles to real life principals. Once the agent is installed and configured, the application security roles can be mapped to real principals. For example, the role Buyer is mapped to an Access Manager role called Staff, and the role Approver is mapped to an Access Manager role called Manager. Thus when user Arvind tries to access the application's protected resources to create a purchase order, the agent allows this access only if this user is a member of the mapped role Staff. Similarly, a user Jamie may wish to approve this purchase order, which will be allowed by the agent only if this user is a member of the mapped role Manager.
A content-based web application can offer pay per-view services. The application may be partitioned into two domains: the public domain that is accessible to anonymous users, and the private domain that is accessible only to the subscribers of this particular service. Furthermore, the protected domain of this application can also be subject to strict conditions based on how the user has authenticated, the time of day, IP address-based conditions and so on. Using Access Manager based URL policies for web resources, an administrator specifies such complex policies for the application resources, which are evaluated by the agent in order to ensure that access to these resources is granted only when all conditions are satisfied. An administrator can set policies that govern access to these resources at any level of granularity, such as that for a single user or for an entire organization. For example, one such policy may govern access to certain resources in such a manner that the user must belong to a particular LDAP Group called Customer and that the time of the day be between 9:00 am and 5:00 p.m. Thus, if user Rajeev attempts to access this resource, the agent allows access only if this user is a member of the LDAP Group Customer, and if the time of day is between 9:00 am and 5:00 p.m.