Patent application number | Description | Published |
20110119532 | METHOD OF DETECTING A FAULT ATTACK - A method of detecting a fault attack including generating a first signature of a first group of data values by performing a single commutative non-Boolean arithmetic operation between all the data values of the first group; generating a second set of data values by performing a permutation of the first set of data values; generating a second signature of the second group of data values by performing said single commutative non-Boolean arithmetic operation between all the data values of the second group; and comparing the first and second signatures to detect a fault attack. | 05-19-2011 |
20110119762 | METHOD AND APPARATUS FOR DETECTION OF A FAULT ATTACK - The invention concerns a method of detecting a fault attack including providing a plurality of blinding values; generating a first set of data elements including a first group of data elements and at least one additional data element generated by performing the exclusive OR between at least one data element in the first group and at least one of the blinding values; generating a second set of data elements corresponding to the exclusive OR between each data element of the first set and a selected one of the plurality of blinding values; generating a first signature by performing a commutative operation between each of the data elements of the first set; generating a second signature by performing the commutative operation between each of the data elements of the second set; and comparing the first and second signatures to detect a fault attack. | 05-19-2011 |
20110126085 | METHOD OF SIGNATURE VERIFICATION - A method of detecting a fault including generating at least one blinded data value based on at least one input value and at least one blinding parameter selected from a plurality of blinding parameters generating a first signature based on said at least one blinded data value; selecting, from a memory storing a plurality of reference signatures, one or more reference signatures and comparing said first signature with said one or more reference signatures in order to detect a fault. | 05-26-2011 |
20110222684 | PROTECTION OF REGISTERS AGAINST UNILATERAL DISTURBANCES - A method for protecting a key intended to be used by an electronic circuit in an encryption or decryption algorithm, including the steps of: submitting the key to a first function taking a selection value into account; storing all or part of the result of this function in at least two registers; when the key is called by the algorithm, reading the contents of said registers and submitting them to a second function taking into account all or part of the bits of the registers; and providing the result of the combination as an input for the algorithm, the second function being such that the provided result corresponds to the key. | 09-15-2011 |
20120106732 | CRYPTOGRAPHIC COUNTERMEASURE METHOD BY DERIVING A SECRET DATA - A method of protecting a circuit from attacks aiming to discover secret data used during the execution of a cryptographic calculation by the circuit, by, executing a transformation calculation implementing a bijective transformation function, receiving as input a secret data, and supplying a transformed data, executing a cryptographic calculation receiving as input a data to process and the transformed data, and executing an inverse transformation calculation receiving as input the result of the cryptographic calculation, and supplying a result that the cryptographic calculation would have supplied if it had been applied to the data to process and directly to the secret data, the data to process belong to a stream of a multiplicity of data, the transformed data being supplied as input to the cryptographic calculation for all the data of the stream. | 05-03-2012 |
20120284796 | PROTECTION OF A VOLATILE MEMORY AGAINST VIRUSES BY MODIFICATION OF THE CONTENT OF AN INSTRUCTION - A method for protecting a volatile memory against a virus, wherein: rights of writing, reading, or execution are assigned to certain areas of the memory; and a first list of opcodes for which the access to the areas is authorized or forbidden is associated with each of these areas. | 11-08-2012 |
20120284808 | PROTECTION OF A NON-VOLATILE MEMORY BY CHANGE OF INSTRUCTIONS - A method for protecting a volatile memory against a virus, wherein: rights of writing, reading, or execution are assigned to certain areas of the memory; and a first list of opcodes authorized or forbidden as a content of the areas is associated with each of these areas. | 11-08-2012 |
20130016826 | PROTECTION OF A MODULAR EXPONENTIATION CALCULATION BY ADDITION OF A RANDOM QUANTITYAANM Teglia; YannickAACI BelcodeneAACO FRAAGP Teglia; Yannick Belcodene FR - A method for protecting a calculation, by an electronic circuit, of a modular exponentiation of a digital quantity, wherein: a first variable is initialized with a random quantity increased by once unit; a second variable is initialized with the product of the digital quantity by the random quantity; a third variable is initialized with the digital quantity; iteratively for all the bits at 1 of an exponent of the modular exponentiation, the first variable is updated by: a) multiplying its content by that of the third variable; and b) subtracting thereto the content of the second variable increased by the random quantity; and once all the bits of the exponent have been processed, the content of the first variable is decreased by the random quantity to provide the result of the modular exponentiation. | 01-17-2013 |
20130016827 | PROTECTION OF A CALCULATION ON AN ELLIPTIC CURVEAANM Teglia; YannickAACI BelcodeneAACO FRAAGP Teglia; Yannick Belcodene FR - A method for protecting a calculation on an elliptic curve, by an electronic circuit, wherein a point of an elliptic curve is multiplied by a digital quantity, comprising the steps of: initializing a first variable with a value which is a function of a random quantity; initializing at least a second variable with a value which is a function of the digital quantity; at least for a bit at 1 of the digital quantity, the first variable is updated by: a) subtracting a multiple of the random quantity; and b) adding the content of the second variable; and once all the bits of the digital quantity have been processed, subtracting from the first variable the product of the point to by the random quantity to provide the result. | 01-17-2013 |
20130016828 | PROTECTION OF A MODULAR EXPONENTIATION CALCULATION BY MULTIPLICATION BY A RANDOM QUANTITYAANM Teglia; YannickAACI BelcodeneAACO FRAAGP Teglia; Yannick Belcodene FR - A method for protecting a calculation, by an electronic circuit, of a modular exponentiation of a digital quantity, wherein: a first variable is initialized with a random quantity; at least one second variable is initialized with a value which is a function of the digital quantity; at least for a bit at 1 of an exponent of the modular exponentiation, the first variable is updated by: a) the quotient of its content and a power of the random quantity; and b) the product of its content by that of the second variable; and once all the exponent bits have been processed, the content of the first variable is divided by the random quantity to provide the result of the modular exponentiation. | 01-17-2013 |
20140079214 | CRYPTOGRAPHIC COUNTERMEASURE METHOD BY DERIVING A SECRET DATA - A method of protecting a circuit from attacks aiming to discover secret data used during the execution of a cryptographic calculation by the circuit, by, executing a transformation calculation implementing a bijective transformation function, receiving as input a secret data, and supplying a transformed data, executing a cryptographic calculation receiving as input a data to process and the transformed data, and executing an inverse transformation calculation receiving as input the result of the cryptographic calculation, and supplying a result that the cryptographic calculation would have supplied if it had been applied to the data to process and directly to the secret data, the data to process belong to a stream of a multiplicity of data, the transformed data being supplied as input to the cryptographic calculation for all the data of the stream. | 03-20-2014 |
20140366135 | DETECTION OF FAULT INJECTIONS IN A RANDOM NUMBER GENERATOR - A method for detecting a fault injection in a random number generation circuit, wherein a bit pattern is mixed to a bit stream originating from a noise source and the presence of this pattern is detected in a signal sampled downstream of the mix. | 12-11-2014 |
20140379770 | Secured Comparison Method of Two Operands and Corresponding Device - A first operation of comparison of the first initial operand with the second initial operand uses at least one comparison operator in such a way as to obtain a first final result word. A second operation of comparison of the second initial operand with the first initial operand uses the at least one comparison operator in such a way as to obtain a second final result word. Another operation checks the values of the bits of the two final result words in relation to a part at least of r combinations of reference values taken from possible combinations of values of these two final result words. These reference combinations represent a valid result of comparison of the two operands including an equality, a relationship of inferiority and a relationship of superiority between the two operands. | 12-25-2014 |
20150063561 | PROTECTION OF A CALCULATION AGAINST SIDE-CHANNEL ATTACKS - A method for protecting a ciphering algorithm executing looped operations on bits of a first quantity and on a first variable initialized by a second quantity, wherein, for each bit of the first quantity, a random number is added to the state of this bit to update a second variable maintained between two thresholds. | 03-05-2015 |