Modelling, verification, and formal analysis of security properties in a P2P system

Abstract

We present a security analysis of the SPREADS 1 system, a distributed storage service based on a centralized peer-topeer architecture. We formally modelled the salient behavior of the actual system using ABCD, a high level specification language with a coloured Petri net semantics, which allowed the execution states of the system to be verified. We verified the behavior of the system in the presence of an external Dolev-Yao attacker, unearthing some replay attacks in the original system. Furthermore, since the implementation is also a formal model, we have been able to show that any execution of the model satisfies certain desirable security properties once these flaws are repaired.

Performance Evaluations of a BSP Algorithm for State Space Construction of Security Protocols

“…We have thus empirically verify our assumption: our methods execute significantly faster and achieve better network and memory use. It is encouraging because we think we can check larger protocols [12] secure P2P exchange of files using truth servers.…”

Evaluating a peer-to-peer storage system in presence of malicious peers

“…One is fully distributed and has been studied in this paper, an earlier version is based on a central MI service and has been considered in [3]. The sensitivity to attacks B and C is an argument in favour of the centralised version.…”

“…The system is currently provided to UbiStorage consumers as a box that is ready to plug on the consumer's network and is pre-installed with a Linux system running the peer-to-peer software as well as end-user services. In [3], the security of these protocols has been assessed from a qualitative point of view, resorting to a formal modelling of the protocols combined with automated model-checking of typical scenarios as well as a manual proof. Model-checking allowed to discover potential flaws based on replay attacks, fixes have been proposed and their quality checked again using modelchecking.…”

A BSP Algorithm for On-the-Fly Checking CTL* Formulas on Security Protocols

“…Finally, in the security domain, we will consider more complex protocols with branching and looping structures, as well as complex data types manipulations. In particular, we will consider protocols for secure storage distributed through peer-to-peer communication [19] because it is currently model using ABCD and generates large state spaces.…”