Formal Verification of Security Protocol Implementations: A Survey

Automated formal verification of security protocols has been mostly focused on analyzing high-level abstract models which, however, are significantly different from real protocol implementations written in programming languages. Recently, some researchers have started investigating techniques that bring automated formal proofs closer to real implementations. This paper surveys these attempts, focusing on approaches that target the application code that implements protocol logic, rather than the libraries that implement cryptography. According to these approaches, libraries are assumed to correctly implement some models. The aim is to derive formal proofs that, under this assumption, give assurance about the application code that implements the protocol logic. The two main approaches of model extraction and code generation are presented, along with the main techniques adopted for each approac

Compiling symbolic attacks to protocol implementation tests

Recently efficient model-checking tools have been developed to find flaws in security protocols specifications. These flaws can be interpreted as potential attacks scenarios but the feasability of these scenarios need to be confirmed at the implementation level. However, bridging the gap between an abstract attack scenario derived from a specification and a penetration test on real implementations of a protocol is still an open issue. This work investigates an architecture for automatically generating abstract attacks and converting them to concrete tests on protocol implementations. In particular we aim to improve previously proposed blackbox testing methods in order to discover automatically new attacks and vulnerabilities. As a proof of concept we have experimented our proposed architecture to detect a renegotiation vulnerability on some implementations of SSL/TLS, a protocol widely used for securing electronic transactions.Comment: In Proceedings SCSS 2012, arXiv:1307.802

miTLS: Verifying Protocol Implementations against Real-World Attacks

International audienceThe TLS Internet Standard, previously known as SSL, is the default protocol for encrypting communications between clients and servers on the Web. Hence, TLS routinely protects our sensitive emails, health records, and payment information against network-based eavesdropping and tampering. For the past 20 years, TLS security has been analyzed in various cryptographic and programming models to establish strong formal guarantees for various protocol configurations. However, TLS deployments are still often vulnerable to attacks and rely on security experts to fix the protocol implementations. The miTLS project intends to solve this apparent contradiction between published proofs and real-world attacks, which reveals a gap between TLS theory and practice. To this end, the authors developed a verified reference implementation and a cryptographic security proof that account for the protocol's low-level details. The resulting formal development sheds light on recent attacks, yields security guarantees for typical TLS usages, and informs the design of the protocol's next version

Knowledge Flow Analysis for Security Protocols

Knowledge flow analysis offers a simple and flexible way to find flaws in security protocols. A protocol is described by a collection of rules constraining the propagation of knowledge amongst principals. Because this characterization corresponds closely to informal descriptions of protocols, it allows a succinct and natural formalization; because it abstracts away message ordering, and handles communications between principals and applications of cryptographic primitives uniformly, it is readily represented in a standard logic. A generic framework in the Alloy modelling language is presented, and instantiated for two standard protocols, and a new key management scheme.Comment: 20 page

A formal methodology for integral security design and verification of network protocols

We propose a methodology for verifying security properties of network protocols at design level. It can be separated in two main parts: context and requirements analysis and informal verification; and formal representation and procedural verification. It is an iterative process where the early steps are simpler than the last ones. Therefore, the effort required for detecting flaws is proportional to the complexity of the associated attack. Thus, we avoid wasting valuable resources for simple flaws that can be detected early in the verification process. In order to illustrate the advantages provided by our methodology, we also analyze three real protocols

Optimistic Non-repudiation Protocol Analysis

The original publication is available at www.springerlink.com ; ISBN 978-3-540-72353-0 (Pring) 0302-9743 (Online) 1611-3349International audienceNon-repudiation protocols with session labels have a number of vulnerabilities. Recently Cederquist, Corin and Dashti have proposed an optimistic non-repudiation protocol that avoids altogether the use of session labels. We have specified and analysed this protocol using an extended version of the AVISPA Tool and one important fault has been discovered. We describe the protocol, the analysis method, show two attack traces that exploit the fault and propose a correction to the protocol