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1. (WO2018060094) METHOD TO COUNTER DCA ATTACKS OF ORDER 2 AND HIGHER ON TABLE-BASED IMPLEMENTATIONS

Pub. No.:    WO/2018/060094    International Application No.:    PCT/EP2017/074062
Publication Date: Fri Apr 06 01:59:59 CEST 2018 International Filing Date: Sat Sep 23 01:59:59 CEST 2017
IPC: H04L 9/00
H04L 9/06
Applicants: GEMALTO SA
Inventors: GOUGET, Aline
Title: METHOD TO COUNTER DCA ATTACKS OF ORDER 2 AND HIGHER ON TABLE-BASED IMPLEMENTATIONS
Abstract:
The present invention relates to a method to counter DCA attacks of order 2 and higher order applied on an encoded table-based (TCabi,j) implementation of block-cipher of a cryptographic algorithm to be applied to a message (m), said method comprising the steps of: - translating a cryptographic algorithm block-cipher to be applied on a message (m) into a series of look-up tables (Tabi,j), - applying secret invertible encodings to get a series of look-up tables (TCi,j), - computing message-dependent masking values, comprising the computation of at least two shares of masking value (mmask1, mmask2) for the input of the table network based on at least two different message derivation functions (F1, F2), - re-randomizing the tables (TCi,j) using the computed message-dependent masking values (mmask1,mmask2), - computing rounds to be applied on the message (m) based on the randomized network of tables (TCi,j).