Abstract: A method for cryptographic signature of a datum comprises determining: a signature point equal to the addition of elements equal to a derived first point and of number equal to a first scalar; a second scalar by subtracting, from the product of the first scalar and of a selected scalar, the product of a third and of a fourth scalar; another signature point equal to the addition of elements equal to a selected point and of number equal to the second scalar, and of elements equal to a derived second point and of number equal to the fourth scalar; and a signature portion based on a private key, on the first scalar, on a coordinate of the signature point and on the datum. The derived first and second point are respectively equal to the addition of elements equal to a generator point and of number equal to a fifth and to the third scalar.

Abstract: Disclosed is a method of verifying integrity of a pair of public and private cryptographic keys within the additive group of the integers modulo N, with N being the product of two primary numbers p and q, the method including: calculating a candidate private exponent d? corresponding to a private exponent d of the private key; and executing a test of integrity. The test of integrity includes a step for verifying the coherence of the candidate private exponent d? with respect to a public exponent e of the public key and to the numbers p and q, the verification step involving a first multiple modulo of the public exponent e of the public key and a second multiple modulo of the public exponent e of the public key.

Abstract: The invention relates to a touch interface comprising, on the one hand, an interfacial surface able to generate a haptic-feedback effect in response to a touch of said surface by a user, and, on the other hand, at least one piezoelectric actuator configured to generate, in said interfacial surface, at least one wave of ultrasonic frequency able to endow the particles of this surface with an elliptical movement having a movement component tangential to said surface, which component is denoted ut(t), and a movement component normal to said surface, which component is denoted un(t), wherein said wave of ultrasonic frequency is chosen so that the amplitude Ut of the tangential component ut(t) and the amplitude Un of the normal component un(t) are substantially equal.

Abstract: A system includes sensor-actuator units fixed onto a plate to be actuated according to at least one predetermined vibratory mode, each sensor-actuator unit having an electromechanical actuator and a deformation or vibratory speed sensor, wherein the electromechanical actuator and the sensor are colocated on the surface, that is to say that the measurement by the sensor is performed in immediate proximity to the electromechanical actuator, this proximity being such that the actuator and the sensor can respectively actuate and measure the same predetermined vibratory mode.

Abstract: A cryptographic method is provided. The cryptographic method comprises an initialisation phase for determining a provisional generator point G? equal to a first product G?=[d?]G, where d? is a first random scalar forming a secret key of N bits and G is a generator point of an elliptical curve, and determining a provisional key Q? equal to a second product Q?=[d?]Q, where Q is a point of the elliptical curve forming a public key. During an encryption phase a second random scalar forming a second secret key k of M bits, with M<N; a public key P is calculated such that P=[k]G?; a coordinate of an intermediate point SP1, of the elliptical curve, equal to a fourth product SP1=[k]Q?; at least one key by application of a derivation function (F1); and data (T1) are encrypted based on said at least one key.

Abstract: The invention proposes a novel type of infective countermeasure against fault injection attacks. Instead of determining the injected error before amplifying it, the novel countermeasure applies the same diffusion function to two intermediate ciphers obtained by executing a cryptographic operation on an input. The error is therefore amplified within the same intermediate ciphers, referred to as infective ciphers after diffusion. It is then possible to use diffusion functions which do not map the cipher 0 as an output equal to 0. A cipher recomposed from bits of undiffused ciphers is also generated. These infective and recomposed ciphers are XOR-combined to provide an output cipher. This approach makes it possible to adapt, by simple duplication of the pairs and associated specific diffusion functions, the protection offered by the countermeasure to a desired number of injected faults.

Abstract: A system includes sensor-actuator units fixed onto a plate to be actuated according to at least one predetermined vibratory mode, each sensor-actuator unit having an electromechanical actuator and a deformation or vibratory speed sensor, wherein the electromechanical actuator and the sensor are colocated on the surface, that is to say that the measurement by the sensor is performed in immediate proximity to the electromechanical actuator, this proximity being such that the actuator and the sensor can respectively actuate and measure the same predetermined vibratory mode.

Abstract: A cryptographic processing method comprises the following steps: obtaining a second number determined by adding to a first number the order of a finite group or a multiple of this order; determining a quotient and a remainder by dividing the second number by a random number; obtaining a third element equal to the combination of elements equal to a first element of the finite group and in number equal to the product of the quotient and the random number; obtaining a fourth element equal to the combination of elements equal to the first element and in number equal to the remainder; determining a second element by combining the third element and the fourth element.

Abstract: A cryptographic method is provided. The cryptographic method comprises an initialisation phase for determining a provisional generator point G? equal to a first product G?=[d?]G, where d? is a first random scalar forming a secret key of N bits and G is a generator point of an elliptical curve, and determining a provisional key Q? equal to a second product Q?=[d?]Q, where Q is a point of the elliptical curve forming a public key. During an encryption phase a second random scalar forming a second secret key k of M bits, with M<N; a public key P is calculated such that P=[k]G?; a coordinate of an intermediate point SP1, of the elliptical curve, equal to a fourth product SP1=[k]Q?; at least one key by application of a derivation function (F1); and data (T1) are encrypted based on said at least one key.

Abstract: Disclosed is a method of verifying integrity of a pair of public and private cryptographic keys within the additive group of the integers modulo N, with N being the product of two primary numbers p and q, the method including: calculating a candidate private exponent d? corresponding to a private exponent d of the private key; and executing a test of integrity. The test of integrity includes a step for verifying the coherence of the candidate private exponent d? with respect to a public exponent e of the public key and to the numbers p and q, the verification step involving a first multiple modulo of the public exponent e of the public key and a second multiple modulo of the public exponent e of the public key.

Abstract: A method of executing a program by a processor, and an electronic entity including such a processor, the method includes the following steps: a calling program calling a subprogram and passing at least one parameter; the subprogram determining a return status indicator; the subprogram determining a return word by using a predetermined function to combine at least the return status indicator and the parameter; returning to the calling program with the determined return word as a result; and the calling program comparing the return word and a determined word determined by using the predetermined function to combine at least one possible value of the return status indicator and the parameter passed when calling the subprogram.

Abstract: A hand to mouth bite counting device is provided that may be worn on a hand, wrist or arm of a user to silently and continuously count the number of bites of food taken by the user. The bite counting device may include a sensing device that collects data corresponding to a sensed movement, and a processor that implements an algorithm to process the collected data and determine whether data collected within a given interval of time corresponds to a bite of food taken by the user. The processor derives a set of attributes from the data collected within the given interval of time to define the sensed movement. The device also provides feedback, goal setting functionality, and long-term statistics to serve as a dietary aid.

Abstract: Devices and methods for masking and unmasking sensitive data, based on a standard cryptographic algorithm defining a ciphering algorithm, and a deciphering algorithm using more resources than the ciphering algorithm are described. The masking of sensitive data is done by applying the deciphering algorithm to the sensitive data to obtain masked sensitive data. The unmasking of the masked sensitive data is done by applying the ciphering algorithm to the masked sensitive data to obtain sensitive data in plain form.

Abstract: Generation of a message m of order ?(n) for a test of the integrity of the generation of a pair of cryptographic keys within the multiplicative group of integers modulo n=p·q, including: —key pair generation including, to generate p and q: a random selection of candidate integers; and a primality test; —a first search of the multiplicative group of integers modulo p for a generator a; —a second search of the multiplicative group of integers modulo q for a generator b; —a third search for a number y, as message m, verifying: 1???n?1, where ?=a mod p and ?=b mod q, the first or second search being performed during the primality test.

Abstract: Disclosed is a secure electronic entity including a memory unit storing data in the form of multiplets and a processing module designed to receive data from an electronic device. The processing module is designed to determine a proof-of-integrity element in accordance with the data received and at least one portion of the stored multiplets, and to transmit the proof-of-integrity element to the electronic device. Also disclosed is a method for verifying the integrity of data stored in such a secure electronic entity.

Abstract: A secure element includes a boot program comprises instructions for the execution a startup step to determine if a non-volatile memory stores an active operating system, and, in the affirmative, to launch execution of the operating system, an authentication step of a updater device, as a function of first authentication data determined by a secure element and second authentication data received from the updater device, and, in response to the authentication step, a storage step of a new operating system received from the update, device in the non-volatile memory and an activation step of the new operating system, when said instructions are executed by a microprocessor.

Abstract: Method for generating a pair of public and private cryptographic keys in the additive group of integers modulo n, where n is the product of two prime numbers p and q, the method including the following steps: calculating a public exponent e for said public key, and calculating a private exponent d for said private key from said public exponent and said public modulus, where d·e=1 mod ?(n), ?(n) being the least common multiple between p-1 and q-1, characterized in that the method furthermore comprises a step: of checking to check that ?(n)=0 mod (p-1) and ?(n)=0 mod (q-1).

Abstract: Method of integrity verification of cryptographic key pairs, the method including an integrity test with: at least one first step implementing one of the private and public keys and an initial test datum, the first step making it possible to generate a first result, at least one second step implementing at least the first result and the key not used during the at least one first step, the second step making it possible to generate a second result, and a comparison of the second result and of the initial test datum, characterized in that the test is re-executed upon each positive comparison, and in that the test is executed at least 2 times.

Abstract: Devices and methods for masking and unmasking sensitive data, based on a standard cryptographic algorithm defining a ciphering algorithm, and a deciphering algorithm using more resources than the ciphering algorithm are described. The masking of sensitive data is done by applying the deciphering algorithm to the sensitive data to obtain masked sensitive data. The unmasking of the masked sensitive data is done by applying the ciphering algorithm to the masked sensitive data to obtain sensitive data in plain form.

Abstract: Method of integrity verification of public and private cryptographic key pairs in the additive group of integers modulo n, with n being the product of two prime numbers p and q, the method including the following steps: of computation (201), on the basis of the number n, of a public exponent e of the public key, and of a private exponent d of the private key, of two candidate factors p? and q? corresponding respectively to the numbers p and q, of verification (206) so as to verify the consistency of the private exponent with respect to the public exponent and to the number n, the verification step involving the candidate factors.