Gemalto Sa

Cp8 Technologies

Nds Corporation

Axalto S.a.

Bull Cp8

Louis Goubin

Jacques Patarin

Mehdi-Laurent Akkar

Aline Gouget

Aviad Kipnis

Pascal Paillier

Karine Villegas

Nicolas Courtois

Olivier Thanh-Khiet Ly

The invention relates to a method for generating a session key between two communicating electronic devices not requiring any prerecorded information in one of the two devices and enabling the authentication of one of said devices. The method uses a close collaboration between a symmetrical algorithm and an asymmetrical algorithm.

Method for establishing a secured communication without preliminary information share

An aim of this invention is to eliminate the risks of aggression 'DPA of the n order' attacks, for all n values, of cryptography electronic assemblies or systems with a secret or private key. The process according to this invention concerns a securing process for an electronic system using a cryptographic calculation procedure using a secret key. The process consists of masking intermediate results in input or output of at least one critical function for the said procedure.

Method for making safe an electronic cryptography assembly with a secret key

The method according to this invention concerns a method for automatically generating cryptographic algorithms with optional supplementary data, said algorithms comprising two different zones: external algorithm secrecy zone, in external parts of the algorithm exposed to side-channel analysis, and an internal purely cryptographic zone that is not exposed to side-channel analysis, such that in the algorithm secrecy zone, the code of the algorithm is locally made of random (or pseudo-random) and independent sequences of instructions and/or table-lookups chosen from some fixed set of instructions and random constants, with some fixed prescribed probability distribution, and such that the internal cryptographic security zone can be any cryptographic algorithm or method that handles algorithmic security only and does not have to be protected against side-channel attacks.

Method and apparatus for generating cryptographic sets of instructions automatically and code generator

The invention concerns a method to secure an electronic assembly implementing any algorithm against attacks by error introduction. The method according to the invention consists in performing an additional calculation using a verification function on at least one intermediate result in order to obtain a calculation signature and in performing a least once more all or part of the calculation in order to recalculate said signature and compare them in order to detect a possible error.

Method to secure an electronic assembly against attacks by error introduction

The invention concerns an automatic method to secure an electronic calculation assembly against attacks by error introduction or by radiation. The following are used: 1) Static information generated by the automatic process; 2) A dynamic part of the memory of the electronic system allocated by the automatic process; 3) Beacons and check points to mark out the code, introduced by the automatic process; 4) Beacon functions storing information in the dynamic memory; 5) History verification functions using the static information and the dynamic memory to check that no errors have been introduced.

Method to secure an electronic assembly executing any algorithm against attacks by error introduction

The invention relates to security for computer systems and a method for protecting computer systems, particularly those employing an encryption for the protection of sensitive information. A cryptographic algorithm is implemented in the protected system using Boolean operations and arithmetic operations wherein at least one variable is separated into several parts, in a Boolean separation using a Boolean operation, and in an arithmetic separation using an arithmetic operation. In order to switch from one of the operations to the other, a predetermined number of Boolean and arithmetic operations is performed on the parts and at least one random number, so that for each of the values appearing during the operation, there is no correlation with the variable.

Method for making a computer system implementing a cryptographic algorithm secure using Boolean operations and arithmetic operations and a corresponding embedded system

The invention provides for a cryptographic method for digital signature. A set Sof k polynomial functions P(x, . . . , x, y, . . . , y) are supplied as a public key, where k, v, and n are integers, x, . . . , xare n+v variables of a first type, and y, . . . , yare k variables of a second type, the set Sbeing obtained by applying a secret key operation on a given set Sof k polynomial functions P'(a, . . . , a, y, . . . , y), a, . . . , adesignating n+v variables including a set of n 'oil' and v 'vinegar' variables. A message to be signed is provided and submitted to a hash function to produce a series of k values b, . . . , b. These k values are substituted for the k variables y, . . . . , yof the set Sto produce a set Sof k polynomial functions P&#x2033;(a, . . . , a), and v values a&#x2032;, . . . , a&#x2032;, are selected for the v &#x201c;vinegar&#x201d; variables. A set of equations P&#x2033;(a, . . . , a&#x2032;)=0 is solved to obtain a solution for a&#x2032;, . . . , a&#x2032;and the secret key operation is applied to transform the solution to the digital signature.

Public-key signature methods and systems

The invention relates to a method for protecting one or more computer systems using the same secret key (Ks) cryptographic algorithm, characterized in that the way in which said calculation is performed depends, for each computer system and for each secret key, on secret data (Ds) stored in a secret area of the computer system or systems.

Method for making secure one or several computer installations using a common secret key algorithm, use of the method and a computer system utilizing the method

The invention concerns a method for protecting an electronic system implementing a cryptographic calculation process involving a modular exponentiation of a quantity (x), said modular exponentiation using a secret exponent (d), characterized in that said secret exponent is broken down into a plurality of k unpredictable values (d, d, . . . , d), the sum of which is equal to said secret exponent.

Growing community of inventors

Paris, France

Louis Goubin