公开(公告)号：US20200076614A1

公开(公告)日：2020-03-05

申请号：US16467957

申请日：2017-12-06

Applicant: GEMALTO SA

Inventor： Mariya GEORGIEVA ,  Aline GOUGET

IPC: H04L9/32 ,  H04L9/00 ,  H04L9/30 ,  H04L9/08

Abstract: The present invention relates to a method of generating a secure RSA key by a server comprising the steps of: •generating (S1) a private RSA key d and a RSA modulus integer N; •splitting (S2) the secret key integer d in j key shares dJ of length n, with j in [1, J], J being an integer, and such that d=d1+d2+ . . . +dJ mod phi(N), with each key share dj being equal to (dj(0) . . . dj(i) . . . dj(n/b−1)) with each key share component dj(i) in {0 . . . 2{circumflex over ( )}b−1} and i in [0, n/b−1], b being an integer inferior to n and phi the Euler's totient function; •encrypting (S3) with a fully homomorphic encryption (FHE) algorithm each key share component dj(i) of the private RSA key d by using a Fully Homomorphic Encryption secret key ps of a set Ss comprising the index couple (i,j), to generate an encrypted key share component edj(i) of said secure RSA key, said set Ss being a set of integer couples, among a predetermined integer number u of disjoint sets {S1, S2 Ss, Ss+1, . . . Su} generated such that: U{Ss}={(i,j) such that i in [0, n/b−1], j in [1, J]} and each said set among {S1, . . . Su} being associated with a Fully Homomorphic Encryption (FHE) secret key.

公开(公告)号：US20170279600A1

公开(公告)日：2017-09-28

申请号：US15078869

申请日：2016-03-23

Applicant: GEMALTO SA

Inventor： Mariya GEORGIEVA ,  Frederic De Portzamparc

IPC: H04L9/00 ,  H04L9/30 ,  G06F7/72

CPC classification number: H04L9/003 ,  G06F7/726 ,  H04L9/3026 ,  H04L9/304

Abstract: A system, method and computer-readable storage medium for decrypting a code c using a modified Extended Euclidean Algorithm (EEA) having an iteration loop independent of the Hamming weight of inputs to the EEA and performing a fixed number of operations regardless of the inputs to the EEA thereby protecting a cryptographic device performing the decryption from side-channel attacks.

公开(公告)号：US20180367305A1

公开(公告)日：2018-12-20

申请号：US16060977

申请日：2016-12-09

Applicant: GEMALTO SA

Inventor： Aline GOUGET ,  Mariya GEORGIEVA

IPC: H04L9/30 ,  G07C13/00 ,  H04L9/32

Abstract: A method for operating an attribute assertion device having a processor and memory to create an unlinkable digital signature-equivalent of an assertion message that is verifiable—by a service provider receiving the unlinkable digital signature-equivalent—as being generated from a digital signature of a known attribute provider having a public key PKAP. Operating the processor of the attribute assertion device to transform a digital signature of the attribute message into an unlinkable digital signature-equivalent using a one-way transformation of the signature, with the transformation process using a random value generated by the attribute assertion device and a challenge provided by the service provider.