1. Field of the Invention
This invention relates generally to computer security systems, and relates more particularly to a system and method for managing and enforcing complex security requirements in a distributed computer network.
2. Description of the Background Art
Computer security issues have become more complex with the continual evolution of contemporary computer systems. As corporations utilize increasingly distributed and open computing environments, the security requirements of an enterprise typically grow accordingly. The complexity of employee, customer and partner access to critical information assets, while assuring proper security, has proven to be a major hurdle. For example, many organizations deploy applications that allow their external business partners, as well as their own internal employees, to access sensitive information resources within the enterprise. In the absence of adequate security measures, an enterprise may thus be subject to the risk of decreased security and confidentiality.
While most organizations focus their security concerns on protecting the internal network from the outside world, it is estimated that 80-90% of all corporate security breaches come from within an organization (source: Aberdeen Group, September 1997). This further underscores the need to specify and enforce an access control security policy within the enterprise network.
In today's complex business environment, specifying, stating, implementing and managing an enterprise access control policy may be both difficult and inefficient. When corporate data and applications revolved around a mainframe model, the problem of defining and managing access to corporate applications was relatively straightforward. Today, the complexity of business methods, as well as the complexity of distributed application architectures, may force companies to resort to manual, ineffective or highly custom approaches to access control in their attempts to implement the business process.
To secure a complex and distributed computer system, the system may typically employ a combination of encryption, authentication, and authorization technologies. Encryption is a means of sending information between participants in a manner that prevents other parties from reading the information. Authentication is a process of verifying a party's identity. Authorization is a technique for determining what actions a participant is allowed to perform.
Encryption and authentication are well-understood and have led to effective network security products, whereas authorization technology is not as well developed, and is often inadequate for many enterprises. The security approach of most companies today is to focus on the authentication of users to ensure that those users are part of the organization or a member of a select group. Authentication can be accomplished with a number of different approaches, from simple password or challenge response mechanisms to smart cards and biometric devices such as a fingerprint reader. Once users are authenticated, however, there is still a significant problem in managing and enforcing their set of privileges, which may be unique and vary widely between users. The same authentication mechanism can be used for every user, but different authorization mechanisms must be developed for most applications. Therefore, reliable and efficient access control is a much more difficult problem facing enterprises today.
Authentication mechanisms often work together with some sort of access control facility that can protect information resources from unauthorized users. Examples of network security products include firewalls, digital certificates, virtual private networks, and single sign-on systems. Some of these products provide limited support for resource-level authorization. For example, a firewall can screen access requests to an application or a database, but does not provide object-level authorization within an application or database. Single Sign-On (SSO) products, for example, maintain a list of resources an authenticated user can access by managing the login process to many different applications. However, firewalls, SSO and other related products are very limited in their ability to implement a sophisticated security policy characteristic of many of today's enterprises. They are limited to attempting to manage access at a login, or “launch level”, which is an all or nothing approach that inherently cannot implement a business-level policy.
A real-world security policy within a large enterprise is a detailed and dynamic knowledge base specific to that organization. The authorization privileges are specific to the constantly evolving set of users, applications, partners, and global policies that the enterprise puts in place to protect its key information resources. A security policy within a large enterprise can consist of tens or hundreds of thousands of individual rules that cover which users are authorized to access particular applications, perform various operations, or manage the delegation and transfer of tasks. Many of these policy rules that implement the business practice of the organization have to be hard coded within custom-built applications or stored in the database.
The key problem is that these policy rules are localized, scattered throughout the organization, and embedded in applications and databases. Such embedding is expensive and error-prone, and mitigates against efficient policy updates. An organization cannot effectively implement and manage the resulting policy. Inconsistencies arise and updates can quickly become unmanageable. Policy queries and analysis from a global perspective are nearly impossible. The resulting policy begins to diverge from the intended business practices of the organization. Compromises are made in the policy implementation at the department level, and auditors can quickly become frustrated.
The increasing security risks associated with the proliferation of distributed computing, including Intranet and Extranet applications, are prompting many organizations to explore a broad range of security solutions for controlling access to their important information assets. Although organizations have a number of solutions to choose from for authenticating users (determining and verifying who is attempting to gain access to the network or individual applications), there is little choice when it comes to controlling what users can do and when they can do it to the extent necessary to implement the kinds of complex security policies required by modern organizations. Organizations have been forced to choose between custom authorization solutions that are costly, error-prone, and difficult to manage, or third-party solutions that are very limited in their ability to control access to information across applications and databases.
A real-world security policy within a large organization is a detailed and dynamic knowledge base that determines which users are authorized to access particular applications, perform various operations or manage the delegation and transfer of tasks, as well as when and under what circumstances they are permitted to do so. Authorization privileges depend upon a constantly evolving set of users, applications, partners, and business polices that comprise the enterprise security policy. A typical enterprise environment consists of several thousand users, hundreds of applications, and a myriad of network resources, resulting in a security policy that can consist of tens or hundreds of thousands of interrelated policy rules.
Typically, organizations attempt to control access to the internals of in-house applications through policy rules that are hard-coded in the application or through stored procedure statements in the database. But as the number of applications and databases grows, this patchwork approach to authorization quickly gets out of hand. First, organizations must incur the costly and time-consuming overhead of developing customized security code for each application. But more importantly, once the code is developed and embedded in an application, the embedded policy rules become impossible to track, difficult to update, and nearly impossible to manage because they are scattered throughout the organization.
With an estimated 80 percent of all security breaches coming from authorized users (source: Forrester Research), advanced policy features and enforcement mechanisms are needed to control access to sensitive information assets. To implement an enterprise policy, organizations need a centralized policy and a powerful way to specify policy rules to give them adequate access control security. At the same time, they need a distributed authorization infrastructure to provide authorization services to all applications with performance and scalability for modern distributed network environments.
Therefore, for the foregoing reasons, an improved system and method are needed to protect the distributed networks of enterprises against unauthorized access to their valuable information assets by managing and enforcing the complex security policy requirements of the organization.
In the preferred embodiment, the system comprises a policy manager located on a server for managing and distributing a local client policy based on a global security policy, and an application guard located on a client or server associated with one or more clients for managing access to securable components as specified by the local client policy. The global policy specifies access privileges of the user to securable components. The policy manager may then distribute a local client policy based on the global policy to the client or server. An application guard located on the client or server then manages authorization requests to the securable components as specified by the local client policy. Each authorization request may be recorded in an audit log to keep track of the authorization requests, whether they were granted or denied, and other useful information.
The system and method of the present invention supports centralized management and distributed authorization. A central policy server stores and manages the policy rules in a centrally administered database. A powerful graphical user interface is used to create, manage, and customize the elements of a policy. Security rules can be specified by both novice and expert users. A dedicated authorization service is associated with one or more applications. The central policy server automatically distributes (over the network) only the relevant portion of the enterprise policy to each remote service. This distributed architecture ensures that authorization requests are not bottlenecked at a central service point and provides unlimited scalability and maximum performance, regardless of the number of applications or policy rules involved.
A more sophisticated security policy is possible because the application has the ability to evaluate access privileges upon every access to the information, during every transaction, and at every data request.
Therefore, the present invention more efficiently and effectively manages and protects computer applications, databases, and network resources against unauthorized access in a distributed computer network.
The present invention relates to an improvement in security techniques to protect computer systems against unauthorized access. The following description is presented to enable one of ordinary skill in the art to make and use the invention and is provided in the context of a patent application and its requirements. Various modifications to the preferred embodiment will be readily apparent to those skilled in the art and the generic principles herein may be applied to other embodiments. Thus, the present invention is not intended to be limited to the embodiment shown but is to be accorded the widest scope consistent with the principles and features described herein.
The present invention includes a system and method for managing and enforcing complex security requirements in a distributed computer network, and comprises a policy manager located on a server for managing and distributing a policy to a client, and an application guard located on the client, the application guard acting to grant or deny access to various components of the client, as specified by the policy.
Referring now to
Similarly client 116 may preferably include a central processing unit (CPU) 132, a read-only memory (ROM) 134, a random-access memory (RAM) 136, a non-volatile memory 138, an input device 140, and a display 142 all connected via a bus 144.
Server 112 preferably contains a program stored in non-volatile memory 124 for managing a policy or a set of rules and then distributing the policy to client 116 via link 114. Client 116 preferably contains a program stored in non-volatile memory 138 for granting or denying access to various components or resources of client 116, as specified by the policy distributed from server 112. For example, various components or resources of client 116 can include applications, functions or procedures within an application, data structures within an application, and database or file system objects referenced by an application.
Referring now to
An authorization policy preferably consists of four components, including objects, subjects, privileges, and conditions. Objects may be applications, or the operations within an application. Examples of objects include applications or methods, web pages, database tables or files, and menu items in a graphical user interface. The granularity of objects has a direct impact on the level of security achieved. The less information an object contains, it is less likely that a user has access to information not needed to perform his job function. On the other hand, the granularity of objects should be balanced against the ease of security management. The more information an object contains, the fewer objects that have to be protected, and the smaller the policy is.
Objects are preferably organized into an object hierarchy. If an object represents an application, then its children objects might represent the methods with the application. Similarly, if an object represents a database, then its children objects might represent the tables and views within the database.
If a user is granted a certain privilege on a parent object, then he is automatically granted the privilege on all the children objects. Similarly, if a user is denied a certain privilege on a parent object, then he is automatically denied the privilege on all the children objects. In other words, privileges are inherited from parent to children objects. Privilege inheritance through the object hierarchy eases security management because rather than granting the same privilege to every child object, the privilege is granted once to the parent object, and if the privileges of an object change, the policy on all the children objects automatically reflect the changes made to the object.
Subjects may be users, or roles containing users, who access protected objects. Subjects correspond to users that have access to information in a system. Users can either be internal or external to a system. Users are authorized to access information in order to perform their job functions. Such access may be controlled so that a user gets access only to the information needed to perform his job function.
An object, such as an application or a database, typically has its own list of users. These are users who can log on to the object and be authenticated by the objects, sometimes through an external authentication server. In a large system, users are preferably maintained separately by one or more directory servers. Users are preferably extracted from objects or directory servers, and are maintained up-to-date by synchronizing with these objects and directory servers.
Alias users may also be supported. An alias of a user is another user who inherits all the privileges of the user under certain conditions. Alias facilitates authorization management by providing fine granularity of control on the propagation of privileges. For example, an alias of a user can be created to perform his job function while he is absent. The inheritance of privileges takes effect only when the user is absent. An alias implements the business requirements of delegation, where the privileges of a user can be delegated to another user under certain conditions. Conditional inheritance of privileges through an alias reduces the burden of security management, because it restricts privilege propagation to situations when certain conditions are satisfied.
Users of an object may be defined as being local to that object. In a typical system, the same user is often represented by different login identifications in different objects. This system may support the notion of a “global” user to capture this situation. Every global user is mapped to a set of local users, one per object. Global users facilitate the centralized management of users throughout the system, even if they are identified by different names in different objects.
A privilege defines the kinds of access that may be allowed on objects. In the preferred embodiment, a privilege is the right to perform a particular action on a specific object. The kinds of privileges that apply to an object depend on the type of the object. Examples of privileges include the right to execute an application, the right to download a web page, the right to query a database table, or the right to view a menu item.
Privileges are granted to users so they can accomplish tasks required for their job. A privilege should be granted to a user only when it is absolutely required for the user to accomplish a task. Excessive granting of unnecessary privileges may lead to compromised security. A user may receive a privilege in two different ways, privileges can be granted to users explicitly (for example, user SMITH can be granted the privilege to execute the payroll application), or privileges can be granted to a role (a named group of privileges), which is then granted to one or more users (for example, a role named “clerk” can be granted the privilege to, execute the payroll application, and user SMITH can be granted the clerk role).
Roles are named groups of privileges that are granted to users or other roles. Users granted to a role are the members of that role. A role is often used to represent the set of privileges needed to perform a job function.
The members of a role automatically inherit all the privileges granted or denied to the role. In addition, roles may be organized into a role hierarchy, where parent roles are granted to children roles. If a parent role is granted a privilege, then the children roles are automatically granted the privilege. Similarly, if a role is denied a privilege, then the children roles are automatically denied the privilege.
Roles of an object may be defined as being local to that object. In a typical system, the same role is often represented by different names in different objects. This system may support the notion of a “global” role to capture this situation. Every global role is mapped to a set of local roles, one per object. Global roles facilitate the centralized management of roles throughout the system, even if they are identified by different names in different objects.
Role membership may be further constrained by the notion of mutual exclusion. Two roles are mutually exclusive if no single user can be granted to both roles simultaneously. Role mutual exclusion implements a business requirement of separation of duty. For example, a submit_budget role and an approve_budget role should be mutually exclusive, because no user should be simultaneously authorized to perform both actions.
In a typical policy, there are preferably two types of access rules, a grant rule, and a deny rule. A grant rule states that a privilege on an object is granted to a subject under an optional constraint. A deny rule states that a privilege on an object is denied to a subject under an optional constraint. Additionally, a wild card “any” may be used as a privilege, object, or subject, meaning that any legitimate value could be substituted in its place.
An access request preferably consists of a privilege, an object, and a subject, representing the fact that the subject request authorization of the privilege on the object. An access request matches a grant rule if the privilege, object, and subject match those in the rule, and the constraint in the rule evaluates to “true.” An access request matches a deny rule if the privilege, object, and subject match those in the rule, and the constraint in the rule does not evaluate to “false.”
An access request is denied if there is a deny rule matching the request, or there are no access rules matching the request. An access request is granted if there are no deny rules matching the request, and there is a grant rule matching the request.
Conditions define the constraints on when objects and subjects can be accessed. The constraints in an access rule specifies further requirements on when the access rule is applicable. These requirements could be conditioned on properties of the object or the subject.
Constraints are preferably expressions formed from conditions and Boolean operators NOT, AND, and OR. Three kinds of built-in conditions may be used: 1) relational operations =, < >, <, <=, >, >= on integers; 2) relational operations =, < >, LIKE, NOTLIKE on strings (the operator LIKE takes a string and a pattern and evaluates to true if the string matches the pattern, the operator NOTLIKE is the negation of LIKE); and 3) set operations IN, NOTIN (the operator IN on integers takes an integer and a set of integers and evaluates to “true” if the integer is in the set, the operator IN on strings is similarly defined, and the operator NOTIN is the negation of IN).
In addition to built-in conditions, users of system 110 may declare custom evaluation functions, which are customer-defined conditions. System 110 may provide an Application Programming Interface (API) for invoking customer-supplied code to evaluate custom evaluation functions. For example, an evaluation function could access a remote database to validate certain properties of the object. Another evaluation function could invoke an external server to authenticate the subject.
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In the
Graphical user interface (GUI) 410 provides a user-friendly set of menu options or management services 412 to fully operate the policy manager. Programs controlled by the menu options may include navigation 414, search 416, distribution 418, edit 420, query 422, and log viewer 424. The operation of these programs are further discussed below in conjunction with
After the policy rules are created or modified using management station 212, they may then be distributed to appropriate clients 116. Management station 212 includes a communication interface 434 in order to pass information between various other components in system 110.
Prior to when the policy rules are distributed, a parser/type checker 428 preferably reviews and reconstructs the policy rules to make sure that they are syntactically and semantically correct according to a predefined policy language. The policy rules pass through a database layer (DB layer) 430 and an open database connectivity layer (ODBC) 432 before being stored as enterprise policy 224. DB layer 430 formats the policy rules into standard database storage tables, and ODBC 432 provides a common interface to various vendor-specific databases.
Enterprise policy 224 is then passed to distributor 214. An optimizer program 436 within distributor 214 determines which application guard 310 needs to receive which policy rules. A differ program 438 determines what type of changes were made to optimized policy 222, and then distributes only the changed policy rules or local client policy 318 to the appropriate application guards 310 through an ODBC layer 440 and a communication interface 442, which enforce access control to local applications and data.
Since the application guards 310 can be distributed among various clients 116, and each application guard 310 has its own specific local client policy 318, the system provides scalability.
Distributor 214 may also be used to optimize administrative policy 226 into an optimized administrative policy or local administrative policy 228 for use with application guard 426 in management station 212.
Referring now to
Application guard 310 supports transactional access control by allowing an application to be aware of the authorization service and to make authorization requests at each and every user interaction, data request, or business-level transaction. In addition, the design and integration of application guard 310 is fundamental to providing access control to business-level objects within an application since the authorization services have visibility to those named policy objects within the application.
In the
In the
Users have the option of implementing application guard 310 locally to application 312, as a service running on the same system as application 312, or as a remote authorization service through a remote procedure call to another server. The advantage of the latter design to would be to offload the application server from handling authorization services or allowing a single authorization server to handle a multiple number of applications. A local implementation would provide maximum performance and minimize any network traffic overhead.
As seen in
The application guard authorization service of the present invention introduces virtually no performance overhead to an existing application 312. The policy rules developed at policy manager 210 are compiled into an optimized form before being distributed to the target application guards 310. This optimized form only distributes attributes relevant to that application guard 310, so that access requests may be evaluated by reviewing only a few rules rather than frequently analyzing the potentially large policy rule base.
Referring back to
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Next, in step 720, the system administrator installs application guards 310 onto client systems 116, as well as installing local client policies 318 onto client systems 116. Then at step 722, the system administrator registers plug-ins 522 into application guards 318 to allow for additional capabilities in order to process authorization requests based on customized code.
Referring now to
In the
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After analyzing and viewing rules or policies, at step 1014 the system administrator may exit from analyze policy 816.
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The invention has been explained above with reference to a preferred embodiment. Other embodiments will be apparent to those skilled in the art in light of this disclosure. For example, the present invention may readily be implemented using configurations other than those described in the preferred embodiment above. Additionally, the present invention may effectively be used in conjunction with systems other than the one described above as the preferred embodiment. Therefore, these and other variations upon the preferred embodiments are intended to be covered by the present invention, which is limited only by the appended claims.
The present application is a continuation of U.S. patent application Ser. No. 09/248,788, entitled, “SYSTEM AND METHOD FOR MAINTAINING SECURITY IN A DISTRIBUTED COMPUTER NETWORK,” filed Feb. 12, 1999 now U.S. Pat. No. 6,158,010, which is related to, and claim priority in, U.S. Provisional Patent Application Ser. No. 60/105,963, entitled “System And Method For Maintaining Security In A Distributed Computer Network,” filed on Oct. 28, 1998.
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Number | Date | Country | |
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Child | 09721557 | US |