ing Cryptographic Protocols with Tree Automata ?

We investigate the applicability of symbolic exploration to the automatic verification of secrecy and authentication properties for time sensitive cryptographic protocols. Our formal specifications are given in multiset rewriting over first order atomic formulas enriched with constraints so as to uniformly model fresh name generation and validity condition of time stamps. Our verification appro...

A methodology is presented for using a general-purpose state enumeration tool, Mur', to analyze cryptographic and security-related protocols. We illustrate the feasibility of the approach by analyzing the Needham-Schroeder protocol, nding a known bug in a few seconds of computation time, and analyzing variants of Kerberos and the faulty TMN protocol used in another comparative study. The eecien...

Algorithms are commonly formalized as Turing machines, which are the basis for defining notions such as running time and space complexity; the exact formalism, however, is of no concern in this lecture. For our purposes, an algorithm A takes some input x ∈ {0, 1}∗, performs some computation, and outputs a value A(x). Running time and space complexity of an algorithm are measured as a function o...

In this note we ooer a perspective on the virtues and limitations of several logics for cryptographic protocols focusing primarily on the logics of authentication. We emphasize the scope limitations of these logics rather than their virtues because (1) we consider their virtues to be better understood and accepted than their limitations , and (2) we hope to stimulate further research that will ...

The universally composable symbolic analysis (UCSA) framework layers Dolev-Yao style symbolic analysis on top of the universally composable (UC) secure framework to construct computationally sound proofs of cryptographic protocol security. The original proposal of the UCSA framework by Canetti and Herzog (2004) focused on protocols that only use public key encryption to achieve 2-party mutual a...

We present principles for the design of cryptographic protocols. The principles are neither necessary nor sufficient for correctness. They are however helpful, in that adherence to them would have avoided a considerable number of published errors. Our principles are informal guidelines. They complement formal methods, but do not assume them. In order to demonstrate the actual applicability of t...

Several quantum process algebras have been proposed and successfully applied in verification of quantum cryptographic protocols. All of the bisimulations proposed so far for quantum processes in these process algebras are state-based, implying that they only compare individual quantum states, but not a combination of them. This paper remedies this problem by introducing a novel notion of distri...

In recent years, formal methods have been developed to analyze and verify cryptographic protocols. We will focus on protocols that rely on iteration or recursion. These protocols typically use special security tokens – such as numbers used only once, called nonces, or keys generated by a principal – to achieve their security assertions. The recursion depth of the computations in such protocols ...

Much attention has been paid to the design of languages for the speci cation of cryptographic protocols. However, the ability to specify their desired behavior correctly is also important; indeed many perceived protocol aws arise out of a misunderstanding of the protocol's requirements. In this talk we give a brief survey of the history of requirements speci cation in formal analysis of cryptog...