Techniques to reduce the TCB of an OS (Statusvortrag)

Datum

20.05.2011

Zeit

11:00 - 12:00

Sprecher

Bernhard Kauer

Zugehörigkeit

Institut für Systemarchitektur, Lehrstuhl Betriebssysteme

Sprache

en

Hauptthema

Informatik

Andere Themen

Informatik

Beschreibung

Operating systems are large and very seldom bug free. Thus they have a large TCB which can be exploited by an attacker. One reason for the ever increasing size of operating systems is that old applications have to be supported forever. The availability of virtualization features in CPUs allows solve this issue by moving legacy code into virtual machines. However, current virtualization environments have the same properties as OSes: they are itself large and error prone. To increase the security of the virtual machines, we build a virtualization environment from scratch that aimed for a minimal TCB. In this talk I will introduce the problem and present my contributions that lead to the TCB of NOVA that is approximately an order of magnitude smaller than that of existing virtualization environments. I will describe how OSLO can be used to remove the boot-code from the TCB, how new implementation techniques minimize the TCB of the VMM as well as the multi-server environment and how an external debugger can be used for to debug the system in a TCB-friendly way. Betreuer: Prof. Dr. Hermann Härtig Fachreferent: Prof. Dr. Christoph Fetzer

Letztmalig verändert: 20.05.2011, 09:35:25