Authors:
Rosario Giustolisi
1
;
Vincenzo Iovino
2
and
Gabriele Lenzini
2
Affiliations:
1
IT University of Copenhagen, Denmark
;
2
University of Luxembourg, Luxembourg
Keyword(s):
Privacy-Preserving Verifiability, Electronic Exam Protocols, Analysis of Security and Privacy.
Related
Ontology
Subjects/Areas/Topics:
Formal Methods for Security
;
Information and Systems Security
;
Security in Information Systems
;
Security Protocols
;
Security Requirements
;
Security Verification and Validation
Abstract:
We introduce the notion of privacy-preserving verifiability for security protocols. It holds when a protocol admits a verifiability test that does not reveal, to the verifier that runs it, more pieces of information about the protocol’s execution than those required to run the test. Our definition of privacy-preserving verifiability is general and applies to cryptographic protocols as well as to human security protocols. In this paper we exemplify it in the domain of e-exams. We prove that the notion is meaningful by studying an existing exam protocol that is verifiable but whose verifiability tests are not privacy-preserving. We prove that the notion is applicable: we review the protocol using functional encryption so that it admits a verifiability test that preserves privacy according to our definition. We analyse, in ProVerif, that the verifiability holds despite malicious parties and that the new protocol maintains all the security properties of the original protocol, so proving
that our privacy-preserving verifiability can be achieved starting from existing security.
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