Static Analysis of Processes for No Read-Up and No Write-Down

We study a variant of the no read-up/no write-down security property of Bell and LaPadula for processes in the -calculus. Once processes are given levels of security clearance, we statically check that a process at a high level never sends names to processes at a lower level. The static check is based on a Control Flow Analysis for the -calculus that establishes a super-set of the set of names to which a given name may be bound and of the set of names that may be sent and received along a given channel, taking into account its directionality. The static check is shown to imply the natural dynamic condition.