6 research outputs found
A Hybrid Analysis for Security Protocols with State
Cryptographic protocols rely on message-passing to coordinate activity among
principals. Each principal maintains local state in individual local sessions
only as needed to complete that session. However, in some protocols a principal
also uses state to coordinate its different local sessions. Sometimes the
non-local, mutable state is used as a means, for example with smart cards or
Trusted Platform Modules. Sometimes it is the purpose of running the protocol,
for example in commercial transactions.
Many richly developed tools and techniques, based on well-understood
foundations, are available for design and analysis of pure message-passing
protocols. But the presence of cross-session state poses difficulties for these
techniques.
In this paper we provide a framework for modeling stateful protocols. We
define a hybrid analysis method. It leverages theorem-proving---in this
instance, the PVS prover---for reasoning about computations over state. It
combines that with an "enrich-by-need" approach---embodied by CPSA---that
focuses on the message-passing part. As a case study we give a full analysis of
the Envelope Protocol, due to Mark Ryan
Dynamic epistemic verification of security protocols: framework and case study
We propose a dynamic epistemic framework for the verification of security protocols. First, we introduce a dynamic epistemic logic equipped with iteration and cryptographic supplements in which we can formalize and check (epistemic) requirements of security protocols. On top of this, we give a general guide how to go from a protocol specification to its representation in our framework. We demonstrate this by checking requirements of a simplified version of a protocol for confidential message comparison
Semantics and Logic for Security Protocols
Contains fulltext :
75885.pdf (author's version ) (Open Access)36 p
Semantics and logic for security protocols
This paper presents a sound BAN-like logic for reasoning about security protocols with theorem prover support. The logic has formulas for sending and receiving messages (with nonces, public and private encryptions etc.), and has both temporal and epistemic operators (describing the knowledge of participants). The logic’s semantics is based on strand spaces. Several (secrecy or authentication) formulas are proven in general and are applied to the Needham-Schroeder(-Lowe), bilateral key exchange and the Otway-Rees protocols, as illustrations.