2026-07-24T17:55:54Z https://drops.dagstuhl.de/oai

oai:drops-oai.dagstuhl.de:7268 2024-03-06T10:39:43Z ddc:004 open_access

Type Abstraction for Relaxed Noninterference Cruz, Raimil Rezk, Tamara Serpette, Bernard Tanter, Éric type abstraction relaxed noninterference information flow control Information-flow security typing statically prevents confidential information to leak to public channels. The fundamental information flow property, known as noninterference, states that a public observer cannot learn anything from private data. As attractive as it is from a theoretical viewpoint, noninterference is impractical: real systems need to intentionally declassify some information, selectively. Among the different information flow approaches to declassification, a particularly expressive approach was proposed by Li and Zdancewic, enforcing a notion of relaxed noninterference by allowing programmers to specify declassification policies that capture the intended manner in which public information can be computed from private data. This paper shows how we can exploit the familiar notion of type abstraction to support expressive declassification policies in a simpler, yet more expressive manner. In particular, the type-based approach to declassification---which we develop in an object-oriented setting---addresses several issues and challenges with respect to prior work, including a simple notion of label ordering based on subtyping, support for recursive declassification policies, and a local, modular reasoning principle for relaxed noninterference. This work paves the way for integrating declassification policies in practical security-typed languages. Schloss Dagstuhl – Leibniz-Zentrum für Informatik Raimil Cruz and Tamara Rezk and Bernard Serpette and Éric Tanter 2017 Is Part Of LIPIcs, Volume 74, 31st European Conference on Object-Oriented Programming (ECOOP 2017) InProceedings Text doc-type:ResearchArticle publishedVersion application/pdf doi:10.4230/LIPIcs.ECOOP.2017.7 urn:nbn:de:0030-drops-72688 https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ECOOP.2017.7 eng https://creativecommons.org/licenses/by/3.0/legalcode