Abstract: Provided is a method for securely transferring data element values stored in a first device to a second device, where each stored data element value being encrypted with a storage key (KSi). It includes mutually agreeing on a short term session key (STK), determining, for each stored data element value an ephemeral key as a sub-sequence of a pseudorandom sequence (bsi) derived from the short term session key (STK), encrypting, each stored data element values using said ephemeral key, decrypting, each data element value encrypted with an ephemeral key, using the storage key (KSi), to obtain KSi-decrypted data element values, transferring said KSi-decrypted data element values from the first device to the second device, obtaining, by the second device, the ephemeral keys from the short term session key (STK), and decrypting the transferred data element values using the obtained ephemeral key.

Abstract: Protection of a data file to be used by a white-box cryptography software application installed in memory of a device to prevent the malevolent use of a digital copy of the data file by a white-box cryptography (WBC) software application installed in memory of another device. The mechanism includes extracting an unique identifier for the device from the environment of the device and modifying data in the data file according to the unique identifier, the available white-box cryptography software application includes a software security layer to retrieve the unique identifier from the environment of the device in which the software application is installed and to use this unique identifier in combination with the stored data file when executing, the result of the execution being correct only in case where the correct unique identifier has been extracted by the executed WBC software application.

Abstract: The present invention relates to a method to protect a data file to be used by a white-box cryptography software application installed in memory of a device to prevent the malevolent use of a digital copy of the data file by a white-box cryptography software application installed in memory of another device, said method comprising the steps of extracting an unique identifier for the device from the environment of the device and modifying data in the data file according to the unique identifier, the available white-box cryptography software application being such that it comprises a software security layer adapted to, when the WBC software application is executed, retrieve the unique identifier from the environment of the device in which it is installed and to use this unique identifier in combination with the stored data file in its execution, the result of the execution being correct only in case where the correct unique identifier has been extracted by the executed WBC software application.

Abstract: The present invention relates to a method of securing by a first processor of a securing device, a software code performing, when executed by an execution device, a sensitive operation performing accesses to a plurality of look-up tables (T0, T1, . . . Tn), wherein said software code comprises first sequences of instructions performing said accesses, said method comprising the steps of: a) generating (S1) a packed table (T) gathering said look-up tables (T0, T1, . . .

Abstract: The method for protecting a cryptography circuit from attacks aiming to discover a secret datum (Di, K) used during execution by the circuit of a cryptography algorithm comprising the application (22) of at least one cryptographic operation (Oi) to the data (Di), said data belonging to a first mathematical structure (E) having at least one group structure and provided with at least one binary operation, is characterized in that it comprises a step (OPi) for protecting said cryptographic operation, comprising applying (20) to said data (Di) at least one first reversible homomorphism (Mi), compatible with said binary operation, before applying (22) said cryptographic operation (Oi), and applying (24) at least one second hornornorphisrn (Mi?1), opposite the first homomorphism (Mi), after applying said cryptographic operation (Oi).

Abstract: The method for protecting a cryptography circuit from attacks aiming to discover a secret datum (Di, K) used during execution by the circuit of a cryptography algorithm comprising the application (22) of at least one cryptographic operation (Oi) to the data (Di), said data belonging to a first mathematical structure (E) having at least one group structure and provided with at least one binary operation, is characterized in that it comprises a step (OPi) for protecting said cryptographic operation, comprising applying (20) to said data (Di) at least one first reversible homomorphism (Mi), compatible with said binary operation, before applying (22) said cryptographic operation (Oi), and applying (24) at least one second hornornorphisrn (Mi?1), opposite the first homomorphism (Mi), after applying said cryptographic operation (Oi).

Abstract: This method is characterized in that it includes the following steps, a step for establishing a key root database in the transmitter and said at least one receiver, a step for generating in the transmitter a sequence of bits called an index, a step for having this index bit sequence transmitted by the transmitter to the receiver, and a step for having the key extracted from the index and from the key root database by the transmitter and said at least one receiver.