The Least Privilege Separation Kernel (LPSK) is part of the Trusted Computing Exemplar (TCX) project. Separation kernels may be used to partition resources in support of the enforcement of mandatory security policies. The LPSK provides services that allow each subject to access resources configured as part of its domain. To ensure permanence of information the LPSK requires a storage hierarchy for its data resources. This thesis describes the design for a LPSK storage hierarchy based on existing LPSK requirements. The design was implemented in a Linux environment to produce a storage hierarchy prototype. Implementation of the prototype proceeded in keeping with principles for developmental security which include minimization, modularity, and hierarchical dependencies. The LPSK storage hierarchy external interfaces belong in three distinct categories: The configuration interfaces are used to construct the storage hierarchy and its contents in a non-LPSK context, initialization interfaces associate data segment handles with data segments that are exported to LPSK subjects, and runtime interfaces support the reading and writing to secondary storage data segments exported to non-LPSK subjects. Testing showed that storage hierarchy interfaces behaved according to specification. This study shows that a storage hierarchy prototype can be designed and implemented based on the LPSK functional specification.
Irvine, Cynthia E. Clark, Paul C.
Naval Postgraduate School (U.S.)
Naval Postgraduate School
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