Bilineaarsed kujutused formaalses krüptograafias
Date
2011
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Tartu Ülikool
Abstract
Krüptograafiliste protokollide turvalisuse testimiseks on loodud erinevad analüsaatorid. Osa neist põhineb predikaatloogika valemitel. Formaalses mudelis pole aga mugav realiseerida aritmeetilisi funktsioone. On kerge arvutada g^a, kui on teada nii g kui a väärtused, kuid protokollides on muutujad üldjuhul väärtustamata. Algebraliste struktuuride omadusi on vaja kirjeldada loogika valemite abil. Mõnede sellist liiki probleemidega on juba tegeldud. Näiteks on realiseeritud Diffie-Hellmani astendamine Horni valemitel põhineva analüsaatoriga ProVerif. Kahjuks see töötab vaid erinevate astendajate lõpliku arvu korral.
Peale astendamist pakuvad aga krüptograafia valdkonnale huvi ka muud algebralised struktuurid, nende hulgas ka bilineaarsed kujutused. Antud uurimistöö eesmärk oli realiseerida bilineaarsete kujutuste arvutamist analüsaatoriga ProVerif ning analüüsida moodustatud protokolliteisendaja abil mõningaid bilineaarseid kujutusi kasutavaid protokolle.
Bilinear mappings are quite powerful mathematical structures that can be used in cryptography. They allow constructing cryptographic primitives that would be otherwise ineffective or even impossible. In formal cryptography, the protocols are based on term algebras and process calculi, and can be represented through Horn clauses for analysis purposes. The security of these protocols can be tested with analyzers based on resolution methods. However, there are problems with realization of arithmetic operations. It is easy to compute g^a if the values of both g and a are known, but the values are usually undefned in the protocols. Some research works have been written about the representation of exponentiation in formal model, but there are still many things that should be done. In this work, an attempt to implement an analysis of bilinear mappings in formal cryptography has been done.
Bilinear mappings are quite powerful mathematical structures that can be used in cryptography. They allow constructing cryptographic primitives that would be otherwise ineffective or even impossible. In formal cryptography, the protocols are based on term algebras and process calculi, and can be represented through Horn clauses for analysis purposes. The security of these protocols can be tested with analyzers based on resolution methods. However, there are problems with realization of arithmetic operations. It is easy to compute g^a if the values of both g and a are known, but the values are usually undefned in the protocols. Some research works have been written about the representation of exponentiation in formal model, but there are still many things that should be done. In this work, an attempt to implement an analysis of bilinear mappings in formal cryptography has been done.