Conference Paper

Computationally Sound Implementations of Equational Theories Against Passive Adversaries.

DCSSI, Paris, France; Loria/CNRS & INRIA Lorraine Projet Cassis, France; LSV/CNRS & INRIA Saclay Projet SECSI & ENS Cachan, France
DOI: 10.1007/11523468_53 Conference: Automata, Languages and Programming, 32nd International Colloquium, ICALP 2005, Lisbon, Portugal, July 11-15, 2005, Proceedings
Source: DBLP

ABSTRACT In this paper we study the link between formal and cryptographic models for security protocols in the presence of a passive adversary. In contrast to other works, we do not consider a fixed set of primitives but aim at re sults for an arbitrary equational theory. We define a framework for comparing a crypto- graphic implementation and its idealization w.r.t. various security notions. In par- ticular, we concentrate on the computational soundness of static equivale nce, a standard tool in cryptographic pi calculi. We present a soundness crite rion, which for many theories is not only sufficient but also necessary. Finally, we establish new soundness results for the Exclusive Or, as well as a theory of ciphers and lists.

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