An approach to Separation of Duties validation for MILS security configurations

Separation of duties (SoD) is an important concept aimed to constrain the excessive powers of subjects regarding system assets and control functions. Ensuring the fact that SoD is properly implemented for the particular task may require the individual approach in every given case.
This paper proposes an approach to SoD validation conducted by the analysis of the security configuration of MILS-based solution. The security policy based on object capabilities is considered for this purpose. For this security policy two basic issues should be met. The first issue is the enough expressivity of the security policy. It is addressed with demonstration of particular examples of usage scenarios. The second issue regards the conditions under which the security problem remains tractable. Solving this issue in context of specifically defined SoD criteria is at the core of this research.
The approach is implemented for the security configurations of Kaspersky Security System.