A compile-time model for safe information flow in object-oriented databases

Security is an important topic for Object-oriented databases (OODB). Discretionary authorization models do not provide the high assurance provided by Mandatory models, the latter ones, however, are too rigid for commercial applications. Therefore discretionary, information-flow control models are needed, especially when transactions containing general methods invocations are considered. This paper first reviews existing security models for object-oriented databases with and without information-flow control. Previous models relied on the run-time checks of every message transferred in the system. This paper uses a simple transaction model and a compile-time approach and presents algorithms for flow control which are applied at Rule-administration and Compile times, thus saving considerable run-time overhead. A proof for correctness is given, and the performance implications are discussed.