RSBAC

RSBAC (Rule Set Based Access Control) is an open source access control framework for current Linux kernels, which has been in stable production use since January 2000 (version 1.0.9a).

Features

*Free open source (GPL) Linux kernel security extension.
*Independent of governments and big companies.
*Several well-known and new security models, e.g. MAC, ACL and RC.
*On-access virus scanning with Dazuko interface.
*Detailed control over individual user and program network accesses.
*Fully access controlled kernel level user management.
*Any combination of security models possible.
*Easily extensible: write your own model for runtime registration.
*Support for latest kernels.
*Stable for production use.
*Very easily portable to other operating systems.

RSBAC

The RSBAC system architecture has been derived and extended from the Generalized Framework for Access Control (GFAC) by Marshall Abrams and Leonard La Padula.

In his essay Rule Set Modeling of a Trusted Computer System, Leonard LaPadula describes how the Generalized Framework for Access Control (GFAC) approach could be implemented in the Unix System V operating system. He introduced the clear separation between Access Enforcement Facility (AEF), Access Decision Facility (ADF) with Access Control Rules (ACR) and Access Control Information (ACI).

The AEF as part of the system call function calls the ADF, which uses ACI and the rules to return a decision and a set of new ACI attribute values. The decision is then enforced by the AEF, which also sets the new attribute values and, in case of allowed access, provides object access to the subject.

This structure requires all security relevant system calls to be extended by AEF interception, and it needs a well defined interface between AEF and ADF. For better modeling, a set of request types was used, in which all system call functionalities were to be expressed. The general structure of the GFAC has also been included in the ISO standard 10181-3 Security frameworks for open systems: Access control framework and into the OpenGroup standard Authorization (AZN) API.

The first RSBAC prototype followed La Padula’s suggestions and implemented some access control policies briefly described there, namely MAC, FC and SIM, as well as the Privacy Model by Simone Fischer-Hübner.

Many aspects of the system have changed a lot since then, e.g. the current framework supports more object types, includes generic list management and network access control, contains several additional security models and supports runtime registration of decision modules and system calls for their administration.

See also

*PaX
*Security-Enhanced Linux
*grsecurity
*Mandatory access control
*Computer security

External links

* [http://www.rsbac.org/ RSBAC homepage]
* [http://www.acsa-admin.org/secshelf/book001/09.pdf Leonard LaPadula's essay on GFAC]
* [http://gentoo-wiki.com/Access_Control_Comparison_Table Gentoo Wiki Access Control Comparison Table]