[en] Covert timing channels in real-time systems allow
adversaries to not only exfiltrate application secrets but also to
mount timing inference based attacks. Much effort has been put
into improving real-time system predictability with the additional
benefit of reducing the former class of confidentiality attacks.
However, the more predictable the system behaves, the easier timing
inference based attacks become. Time-triggered scheduling
is particularly vulnerable to these types of attacks due to offline
constructed tables that are scheduled with clock synchronization
and OS-timer predictability. In this paper, we obfuscate timetriggered
scheduling to complicate timing inference based attacks
while maintaining strong protection against exfiltration attacks.
