Timed Spi- Calculus with Types for Secrecy and Authenticity

摘要

We present a discretely timed spi-calculus. A primitive for key compromise allows us to model key compromise attacks, thus going beyond the standard Dolev-Yao attacker model. A primitive for reading a global clock allows us to express protocols based on timestamps, which are common in practice. We accompany the timed spi-calculus with a type system, prove that well-typed protocols are robustly safe for secrecy and authenticity and present examples of well-typed protocols as well as an example where failure to typecheck reveals a (well-known) flaw.