Secrecy by Witness-Functions on Increasing Protocols

TL;DR

This paper introduces a novel formal method for static analysis of cryptographic protocols to ensure secrecy, by verifying that the security level of each component does not decrease during protocol execution.

Contribution

It presents a new witness-function-based approach for analyzing protocol secrecy and applies it to an amended Woo-Lam protocol as a case study.

Findings

The method successfully verifies secrecy properties of the analyzed protocol.

It detects potential security level reductions in protocol components.

The approach provides a systematic way to ensure protocol secrecy.

Abstract

In this paper, we present a new formal method to analyze cryptographic protocols statically for the property of secrecy. It consists in inspecting the level of security of every component in the protocol and making sure that it does not diminish during its life cycle. If yes, it concludes that the protocol keeps its secret inputs. We analyze in this paper an amended version of the Woo-Lam protocol using this new method.