Abstract
The designs of applications for multilevel systems cannot merely duplicate those of the untrusted world. When applications are built on a high assurance base, they will be constrained by the underlying policy enforcement mechanism. Consideration must be given to the creation and management of multilevel data structures to rely upon the TCB\'s security policy enforcement services rather than build new access control services beyond the TCB perimeter.
The results of an analysis of the design of a general purpose fiule system developed to execute as an untrusted applicatioin on a high assurance TCB are presented. The design illustrates a number of solutions to problems resulting from a high assurance environment.
