Linear Declassification

  • Yûta Kaneko
  • Naoki Kobayashi
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4960)


We propose a new notion of declassification policy called linear declassification. Linear declassification controls not only which functions may be applied to declassify high-security values, but also how often the declassification functions may be applied. We present a linear type system which guarantees that well-typed programs never violate linear declassification policies. To state a formal security property guaranteed by the linear declassification, we also introduce linear relaxed non-interference as an extension of Li and Zdancewic’s relaxed non-interference. An application of the linear relaxed non-interference to quantitative information flow analysis is also discussed.


Security Policy Security Level Operational Semantic Information Leakage Security Variable 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Yûta Kaneko
    • 1
  • Naoki Kobayashi
    • 1
  1. 1.Graduate School of Information SciencesTohoku University 

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