Patent application number | Description | Published |
20100287386 | SECURE INTEGRATED CIRCUIT COMPRISING MEANS FOR DISCLOSING COUNTERPART MASK VALUES - An integrated circuit includes a communication interface circuit, a cryptographic algorithm, a countermeasure configured to protect the cryptographic algorithm against side-channel attacks, and a mask generator configured to provide the countermeasure with mask values. The integrated circuit is configured to execute a specific command requiring the disclosure of mask values used by the countermeasures to protect the cryptographic algorithm during a cryptographic session, and, in response to such a command, to send the mask values through the communication interface circuit. | 11-11-2010 |
20110246119 | PROCESS FOR TESTING THE RESISTANCE OF AN INTEGRATED CIRCUIT TO A SIDE CHANNEL ANALYSIS - A process for testing an integrated circuit includes collecting a set of points of a physical property while the integrated circuit is executing a multiplication, dividing the set of points into a plurality subsets of lateral points, calculating an estimation of the value of the physical property for each subset, and applying to the subset of lateral points a step of horizontal transversal statistical processing by using the estimations of the value of the physical property, to verify a hypothesis about the variables manipulated by the integrated circuit. | 10-06-2011 |
20110246789 | INTEGRATED CIRCUIT PROTECTED AGAINST HORIZONTAL SIDE CHANNEL ANALYSIS - An integrated circuit including a multiplication function configured to execute a multiplication operation of two binary words x and y including a plurality of basic multiplication steps of components xi of word x by components yj of word y is described. The multiplication function of the integrated circuit is configured to execute two successive multiplications by modifying, in a random or pseudo-random manner, an order in which the basic multiplication steps of components xi by components yj are executed. | 10-06-2011 |
20130055025 | MICROPROCESSOR PROTECTED AGAINST MEMORY DUMP - A microprocessor including a memory and a central processing unit configured to sign a binary word written in the memory, and during the reading of a binary word in the memory, verify the signature of the binary word and, if the signature is invalid, launching a protective action of the memory. According to the invention, the central processing unit is configured to execute a write instruction of a binary word accompanied by an invalid signature in a memory zone, so that a later read of the memory zone by the central processing unit launches the protective action. | 02-28-2013 |
20140351603 | ENCRYPTION PROCESS PROTECTED AGAINST SIDE CHANNEL ATTACKS - The invention relates to a symmetric encryption process executed by a microcircuit to transform a message into an encrypted message from a secret key, the process including a first round, intermediary rounds, and a last round. According to the invention, the process includes several executions of the first round and of the last round, and a number of executions of at least one intermediary round, the number of executions being less than the number of executions of the first and last rounds. The invention is particularly applicable to DES, Triple DES, and AES processes. | 11-27-2014 |
20140355758 | METHOD OF GENERATING PRIME NUMBERS PROVEN SUITABLE FOR CHIP CARDS - The invention relates to a method for generating a prime number, implemented in an electronic device, the method including steps of calculating a candidate prime number having a number of bits, using the formula: Pr=2P·R+1, where P is a prime number and R is an integer, applying the Pocklington primality test to the candidate prime number, rejecting the candidate prime number if it fails the Pocklington test, generating the integer from an invertible number belonging to a set of invertible elements modulo the product of numbers belonging to a group of small prime numbers greater than 2, so that the candidate prime number is not divisible by any number of the group, the prime number P having a number of bits equal, to within one bit, to half or a third of the number of bits of the candidate prime number. | 12-04-2014 |
20140358980 | METHOD OF GENERATING PROVEN PRIME NUMBERS SUITABLE FOR BEING IMPLEMENTED IN A SMART CARD - The invention relates to a method for generating a prime number, implemented in an electronic device, the method including steps of generating a prime number from another prime number using the formula Pr=2P·R+1, where P is a prime number having a number of bits lower than that of the candidate prime number, and R is an integer, and applying the Pocklington primality test to the candidate prime number, the candidate prime number being proven if it passes the Pocklington test. According to the invention, the size in number of bits of the candidate prime number is equal to three times the size of the prime number, to within one unit, the generated candidate prime number being retained as candidate prime number only if the quotient of the integer division of the integer by the prime number is odd. | 12-04-2014 |
20150339102 | Cryptography Method Comprising an Operation of Multiplication by a Scalar or an Exponentiation - A cryptographic data processing method, implemented in an electronic device including a processor, the method including steps of providing a point of an elliptic curve in a Galois field, and a whole number, and of calculating a scalar product of the point by the number, the coordinates of the point and the number having a size greater than the size of words that may be processed directly by the processor, the scalar multiplication of the point by the number including steps of: storing scalar multiples of the point multiplied-by the number 2 raised to a power belonging to a series of whole numbers, setting a resulting point for each non-zero bit of the first number, adding the resulting point and one of the stored multiple points, and providing at the output of the processor the resulting point as result of the scalar product. | 11-26-2015 |