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Relations among privacy notions for signcryption and key invisible "sign-then-encrypt"

Journal Article


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Abstract


  • Signcryption simultaneously offers authentication through

    unforgeability and confidentiality through indistinguishability against

    chosen ciphertext attacks by combining the functionality of digital signatures

    and public-key encryption into a single operation. Libert and

    Quisquater (PKC 2004) extended this set of basic requirements with the

    notions of ciphertext anonymity (or key privacy) and key invisibility to

    protect the identities of signcryption users and were able to prove that

    key invisibility implies ciphertext anonymity by imposing certain conditions

    on the underlying signcryption scheme.

    This paper revisits the relationship amongst privacy notions for signcryption.

    We prove that key invisibility implies ciphertext anonymity

    without any additional restrictions. More surprisingly, we prove that key

    invisibility also implies indistinguishability against chosen ciphertext attacks.

    This places key invisibility on the top of privacy hierarchy for

    public-key signcryption schemes.

    On the constructive side, we show that general “sign-then-encrypt”

    approach offers key invisibility if the underlying encryption scheme satisfies

    two existing security notions, indistinguishable against adaptive

    chosen ciphertext attacks and indistinguishability of keys against adaptive

    chosen ciphertext attacks. By this method we obtain the first key

    invisible signcryption construction in the standard model.

UOW Authors


  •   Wang, Yang (external author)
  •   Manulis, Mark (external author)
  •   Au, Man Ho Allen (external author)
  •   Susilo, Willy

Publication Date


  • 2013

Citation


  • Wang, Y., Manulis, M., Au, M. & Susilo, W. (2013). Relations among privacy notions for signcryption and key invisible "sign-then-encrypt". Lecture Notes in Computer Science, 7959 187-202. Brisbane, QLD Relations among privacy notions for signcryption and key invisible "sign-then-encrypt"

Scopus Eid


  • 2-s2.0-84884497322

Ro Full-text Url


  • http://ro.uow.edu.au/cgi/viewcontent.cgi?article=2331&context=eispapers

Ro Metadata Url


  • http://ro.uow.edu.au/eispapers/1322

Has Global Citation Frequency


Number Of Pages


  • 15

Start Page


  • 187

End Page


  • 202

Volume


  • 7959

Place Of Publication


  • Germany

Abstract


  • Signcryption simultaneously offers authentication through

    unforgeability and confidentiality through indistinguishability against

    chosen ciphertext attacks by combining the functionality of digital signatures

    and public-key encryption into a single operation. Libert and

    Quisquater (PKC 2004) extended this set of basic requirements with the

    notions of ciphertext anonymity (or key privacy) and key invisibility to

    protect the identities of signcryption users and were able to prove that

    key invisibility implies ciphertext anonymity by imposing certain conditions

    on the underlying signcryption scheme.

    This paper revisits the relationship amongst privacy notions for signcryption.

    We prove that key invisibility implies ciphertext anonymity

    without any additional restrictions. More surprisingly, we prove that key

    invisibility also implies indistinguishability against chosen ciphertext attacks.

    This places key invisibility on the top of privacy hierarchy for

    public-key signcryption schemes.

    On the constructive side, we show that general “sign-then-encrypt”

    approach offers key invisibility if the underlying encryption scheme satisfies

    two existing security notions, indistinguishable against adaptive

    chosen ciphertext attacks and indistinguishability of keys against adaptive

    chosen ciphertext attacks. By this method we obtain the first key

    invisible signcryption construction in the standard model.

UOW Authors


  •   Wang, Yang (external author)
  •   Manulis, Mark (external author)
  •   Au, Man Ho Allen (external author)
  •   Susilo, Willy

Publication Date


  • 2013

Citation


  • Wang, Y., Manulis, M., Au, M. & Susilo, W. (2013). Relations among privacy notions for signcryption and key invisible "sign-then-encrypt". Lecture Notes in Computer Science, 7959 187-202. Brisbane, QLD Relations among privacy notions for signcryption and key invisible "sign-then-encrypt"

Scopus Eid


  • 2-s2.0-84884497322

Ro Full-text Url


  • http://ro.uow.edu.au/cgi/viewcontent.cgi?article=2331&context=eispapers

Ro Metadata Url


  • http://ro.uow.edu.au/eispapers/1322

Has Global Citation Frequency


Number Of Pages


  • 15

Start Page


  • 187

End Page


  • 202

Volume


  • 7959

Place Of Publication


  • Germany