Paper 2012/469

Perfect Keyword Privacy in PEKS Systems

Mototsugu Nishioka

Abstract

This paper presents a new security notion, called \emph{perfect keyword privacy (PKP)}, for non-interactive public-key encryption with keyword search (PEKS) \cite{bcop04}. Although the conventional security notion for PEKS guarantees that a searchable ciphertext leaks no information about keywords, it gives no guarantee concerning leakage of a keyword from the trapdoor. PKP is a notion for overcoming this fatal deficiency. Since the trapdoor has verification functionality, the popular concept of ``indistinguishability'' is inadequate for capturing the notion of keyword privacy from the trapdoor. Hence, our formalization of PKP depends on the idea of formalizing a perfectly one-way hash function \cite{can97,cmr98}. We also present \emph{IND-PKP security} as a useful notion for showing that a given PEKS scheme has PKP. Furthermore, we present PKP+ and IND-PKP+ as enhanced notions of PKP and IND-PKP, respectively. Finally, we present several instances of an IND-PKP or IND-PKP+ secure PEKS scheme, in either the random oracle model or the standard model.

Metadata
Available format(s)
PDF
Category
Public-key cryptography
Publication info
Published elsewhere. Full version of ProvSec 2012 paper
Keywords
PEKSperfectly one-way hash function
Contact author(s)
mototsugu nishioka rc @ hitachi com
History
2012-08-18: received
Short URL
https://ia.cr/2012/469
License
Creative Commons Attribution
CC BY

BibTeX

@misc{cryptoeprint:2012/469,
      author = {Mototsugu Nishioka},
      title = {Perfect Keyword Privacy in PEKS Systems},
      howpublished = {Cryptology ePrint Archive, Paper 2012/469},
      year = {2012},
      note = {\url{https://eprint.iacr.org/2012/469}},
      url = {https://eprint.iacr.org/2012/469}
}
Note: In order to protect the privacy of readers, eprint.iacr.org does not use cookies or embedded third party content.