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1

Implementation of Pairing-Based Cryptographic Trust Infrastructure in Mobile Environment

Hyla T., El Fray I, Maćków W., Pejaś J.

Przegląd Elektrotechniczny

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2015

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R. 91, nr 2

93-97

EN

Current trends in information system design show that users should have access to services provided by information system offered on their mobile devices. Because many information systems store sensitive information, appropriate protection mechanisms must be deployed. This paper presents the software libraries (APIs) that can be used to implement pairing-based systems on mobile devices. Variety of mobile devices causes that is necessary to design a generic trust infrastructure that will allow to implement efficiently a system that uses parings. There are two basic paradigms that can be used: client-server or cloud-based. The analysis of pros and cons of the architectures showed that it is faster and easier to implement pairing application using cloud-based approach mainly because of the lower number of components required to implement, e.g., the library containing pairing calculations must be only prepared for one operating system instead of many that are using different technologies. The tests conducted using cloud-based demonstrator showed, that in case of documents signing and verification with auxiliary server instead of the mobile device, the pairing calculation time is marginally short in relation to the required to retrieve documents from a remote location.

PL

Aktualne trendy w projektowaniu systemów informacyjnych pokazują, że użytkownik powinien mieć dostęp do usług systemów IT za pomocą urządzeń mobilnych. W przypadku przechowywania informacji wrażliwej w systemach informacyjnych muszą być wdrożone odpowiednie mechanizmy zabezpieczeń. W artykule zaprezentowano biblioteki programowe (API), umożliwiające implementacje systemów wykorzystujących odwzorowania dwuliniowe na urządzeniach mobilnych. Różnorodność urządzeń mobilnych powoduje, że konieczne jest zaprojektowanie ogólnej infrastruktury zaufania, w szczególności przy założeniu wykorzystania odwzorowań dwuliniowych. W artykule zostały przeanalizowane dwa podstawowe podejścia bazujące na modelu klient-serwer i modelu bazującym na chmurze. Testy bazujące na demonstratorze wykorzystującym model chmury pokazały, że czas obliczeń odwzorowania przy podpisywaniu i weryfikowaniu podpisu cyfrowego jest bardzo mały w stosunku do czasu pobierania plików ze zdalnych serwerów.

2

Uogólnione struktury uprawnień z hierarchią

Pragacz A.

Studia Bezpieczeństwa Narodowego

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2014

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R. 4, Nr 6

299--316

PL

Struktury dostępu są używane przy zagadnieniach bezpieczeństwa związanych z sytuacjami gdzie jeden lub więcej podmiotów próbuje uzyskać pewien zasób. Przedstawimy uogólnienie struktur dostępu na przypadek wielu zasobów, co pozwala na zgrabne ujęcie schematów progowych i hierarchicznych. Zaprezentujemy też użycie tzw. iloczynu dwuliniowego, deﬁniowanego w grupie punktów n-torsyjnych krzywej eliptycznej nad ciałem skończonym na dwóch przykładowych hierarchicznych schematach przydzielania kluczy.

EN

Access structures are used in cases associated with situations when one or more entities are trying to get a resource. We will present a generalization to the case of access structures many resources, which allows for a nice description of thresholds and hierarchical schemes. We will also present the use of the so-called bilinear product, deﬁned in the group of n-torsion points of an elliptic curve over a ﬁnite ﬁeld on two exemplary hierarchical allocation key schemes.

3

Enhanced ID-based signature scheme

Pomykała J.

Przegląd Elektrotechniczny

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2014

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R. 90, nr 2

113--116

EN

In the paper we present the design of new digital signature protocol with the secretly hidden warning in the Gap Diffie-Hellman group. The proposed scheme is the extended Id based protocol applying the idea of Schnorr signature and the subliminal channel defined by Simmons.

PL

W pracy przedstawiono projekt nowego protokołu cyfrowego podpisu z ukrytym ostrzeżeniem wykorzystujący grupę DiffiegoHellmana z luką obliczeniowo-decyzyjną. Proponowany schemat jest oparty na rozszerzonym protokole podpisu bazującego na tożsamości i wykorzystuje schemat C. P Schnorra i ideę kanału podprogowego zainicjowaną przez G. Simmonsa.

4

Cryptanalysis and Improvement of a Certificateless Multi-proxy Signature Scheme

Tian M., Yang W., Huang L.

Fundamenta Informaticae

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2014

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Vol. 129, nr 4

365--375

EN

Certificateless cryptography is a new type of public key cryptography,which removes the certificate management problem in traditional public key cryptography and the key escrow problem in identity-based public key cryptography. Multi-proxy signature is an extension of proxy signature, which allows an original signer authorizing a group of proxy signers and only the cooperation of all proxy signers in the group can create valid proxy signatures on behalf of the original signer. Recently, Jin andWen combined certificateless cryptographywith multi-proxy signature, and proposed a model as well as a concrete scheme of certificateless multi-proxy signature. They claimed that their scheme is provably secure in their security model. Unfortunately, in this paper by giving two attacks, we will show that their certificateless multi-proxy signature scheme can be broken. The first attack indicates their security model is flawed and the second attack indicates their certificateless multi-proxy signature scheme is insecure. Possible improvements are also suggested to prevent these attacks.

5

An efficient and provably - secure digital signature scheme based on elliptic curve bilinear pairings

Islam S. K. H., Biswas G. P.

Theoretical and Applied Informatics

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2012

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Vol. 24, No. 2

109-118

EN

We proposed an efficient and secure digital signature scheme using elliptic curve cryptography (ECC) and bilinear pairings in this paper. The proposed scheme employs the general cryptographic hash function (i.e., SHA-1) instead of map-to-point function, because the map-to-point is a cost-intensive operation and it is usually implemented as a probabilistic algorithm. Further, our scheme is computationally efficient as one bilinear paring and three elliptic curve scalar point multiplication operations are executed for signature generation and verification, and thus the scheme requires much lesser computation cost than other related schemes. In addition, in the random oracle model, our scheme is proven to be existential unforgeable against the adaptive chosen message and identity attacks (EUF-CMA) based on a variation of the collusion attack algorithm with ktraitors (k-CAA3) problem.

6

Anonymous signer verifiable encrypted signature from bilinear pairing

Pomykała J., Trabszys T.

Control and Cybernetics

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2009

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Vol. 38, no 3

705-712

EN

In this paper we propose and prove the security of the new cryptographic primitive called the Anonymous Signer Verifiable Encrypted Signature (ASVES), joining the idea of the group signature and the verifiable encrypted signature. It satisfies the traditional requirements of the group signature (unforgeability, anonymity, unlinkability, traceability) and the opacity condition known from the verifiable encrypted signatures. The corresponding scheme may be applied for the fair exchange protocols. Our construction is based on bilinear pairings, defined in the Gap Diffie-Hellman groups.

7

Directed threshold signcryption scheme from bilinear pairing under sole control of designated signcrypter

Pejaś J.

Metody Informatyki Stosowanej

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2008

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nr 4 (Tom 17)

161--172

EN

The paper presents a new ID-based directed threshold signcryption scheme derived from a bilinear pairing and a gap Diffie-Hellman groups. This scheme (called ID-DTS-DS) combines the functionalities of signature and encryption and allows a designated signcrypter to prepare an encrypted and a signed message in cooperation of an authorized subset of shareholders being in a possession of the shares related to a signcrypter’s private key. Furthermore, our scheme guarantees that an encryption and a signature process can be successfully finished only under a signcrypter’s sole control. We analyze the security of the ID-DTS-DS scheme and show its correctness, verifiable directedness, public non-repudiation verifiability, confidentiality and unforgeability.