Formal firewall conformance testing: an application of test and proof techniques

Abstract

This is the peer reviewed version of the following article: Brucker . D., Brügger L., and Wolff B. (2014), Formal firewall conformance testing: an application of test and proof techniques, Softw. Test. Verif. Reliab., 25, 34-71,, which has been published in final form at http://dx.doi.org/10.1002/stvr.1544. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving (http://olabout.wiley.com/WileyCDA/Section/id-820227.html#terms).eprints@whiterose.ac.uk https://eprints.whiterose.ac.uk/ Reuse Unless indicated otherwise, fulltext items are protected by copyright with all rights reserved. The copyright exception in section 29 of the Copyright, Designs and Patents Act 1988 allows the making of a single copy solely for the purpose of non-commercial research or private study within the limits of fair dealing. The publisher or other rights-holder may allow further reproduction and re-use of this version -refer to the White Rose Research Online record for this item. Where records identify the publisher as the copyright holder, users can verify any specific terms of use on the publisher's website. TakedownIf you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing eprints@whiterose.ac.uk including the URL of the record and the reason for the withdrawal request. SUMMARYFirewalls are an important means to secure critical ICT infrastructures. As configurable off-the-shelf products, the effectiveness of a firewall crucially depends on both the correctness of the implementation itself as well as the correct configuration. While testing the implementation can be done once by the manufacturer, the configuration needs to be tested for each application individually. This is particularly challenging as the configuration, implementing a firewall policy, is inherently complex, hard to understand, administrated by different stakeholders and thus difficult to validate. This paper presents a formal model of both stateless and stateful firewalls (packet filters), including NAT, to which a specification-based conformance test case generation approach is applied. Furthermore, a verified optimisation technique for this approach is presented: starting from a formal model for stateless firewalls, a collection of semantics-preserving policy transformation rules and an algorithm that optimizes the specification with respect of the number of test cases required for path coverage of the model are derived. We extend an existing approach that integrates verification and testing, that is, tests and proofs to support conformance testing of network policies. The presented approach is supported by a test framework that allows to test actual firewalls using the test cases generated on the basis of the formal model. Finally, a report on several larger case studies is presented.

Security Testing

“…Thus, we focus in this section on security testing techniques that allow to find these kind of vulnerabilities. For instance, we exclude techniques for ensuring the security of the underlying infrastructure such as the network configuration, as, e.g., discussed in [15,20] as well as model-based testing techniques (as discussed in Section 5.1) that are in particular useful for finding logical security flaws. While a holistic security testing strategy makes use of all available security testing strategies, we recommend to concentrate efforts first on techniques for the most common vulnerabilities.…”

Reasoning about firewall policies through refinement and composition

“…TypesCodes ::= (0,0) | (3,0) | (3,1) | (3,2) | (3,3) | (3,4) | (3,5) | (3,6) | (3,7) | (3,8) | (3,9) | (3,10) | (3,11) | (3,12) | (3,13) | (3,14) | (3,15) | (4,0) | (5,0) | (5,1) | (5,2) | (5,3) | (6,0) | (8,0) | (9,0) | (9,16) | (10,0) | (11,0) | (11,1) | (12,0) | (12,1) | (12,2)…”

Performance impact of commercial industrial firewalls on networked control systems

“…Several papers exist in the literature that focus on the performance analysis of firewalls [6][7][8][9]. Unfortunately, this kind of studies provide mean values of throughput and latency obtained for popular (standard) protocols such as TCP/IP, HTTP, FTP and so on, while they do not take into account those solutions adopted in industrial networks.…”