摘要:
A method of secure cryptographic calculation includes formulating a first list of first random quantities, formulating a first non-linear substitution operator masked with at least part of the first list, and formulating a second list determined from the first list. The second list includes second random quantities respectively determined from the first random quantities. A second non-linear substitution operator masked with at least part of the second list is formulated. At least two successive implementations of a cryptographic calculation algorithm are performed that includes N rounds of calculations carried out successively to obtain output data based on input data and of a secret key, with a data path of the cryptographic calculation algorithm being masked.
摘要:
A method and a circuit for masking a digital word by application of a random bijection, including applying at least one first operation including selecting a non-disjoint subset of the word having its position and size depending on a first random quantity, and assigning to each bit of the subset, the state of the bit having a symmetrical position with respect to the middle of the subset, to obtain a masked digital quantity.
摘要:
A method and a circuit for detecting a loss in the equiprobable character of a first output bit flow originating from at least one first element of normalization of an initial bit flow, including analyzing the flow rate of the normalization element.
摘要:
A processor for executing a Rijndeal algorithm which applies a plurality of encryption rounds to a data block array in order to obtain an array of identical size, each round involving a key block array and a data block substitution table, wherein said processor comprises: a first input register (102) containing an input data block column; an output register (111) containing an output data block column or an intermediate block column; a second input register (101) containing a key block column or the intermediate data blocks; a block substitution element (104) receiving the data one block at a time following the selection (103) thereof in the first register and providing, for each block, a column of blocks; an element (109) applying a cyclic permutation to the substitution circuit column blocks; and an Exclusive-OR combination element (110) combining the permutation circuit column blocks with the content of the second register, the result of said combination being loaded into the output register.
摘要:
A method and an element of ciphering by an integrated processor of data to be stored in a memory, including applying a ciphering algorithm which is a function of a key specific to the integrated circuit and of an initialization vector, and of memorizing at least the ciphered data, the initialization vector depending at least on the address of storage of the data in the memory.
摘要:
A method for protecting the execution of a main program against possible traps, including, on occurrence of an instruction from the main program, starting a time counter of a given count according to next instructions of the main program, and executing, once the counter has reached its count, at least one instruction of a secondary program from which the result of the main program depends.
摘要:
A method for protecting a generation, by an electronic circuit, of at least one prime number by testing the prime character of successive candidate numbers, including: for each candidate number: the calculation of a reference number involving at least one first random number, and at least one primality test based on modular exponentiation calculations; and for a candidate number having successfully passed the primality test: a test of consistency between the candidate number and its reference number.
摘要:
A method and a circuit for detecting a possible loss of the equiprobable character of a first output bit flow originating from at least one first normalization element of an initial bit flow, consisting of submitting the initial flow to at least one second normalization element of a nature different from the first one, pairing, bit to bit, the flows originating from the two elements, and checking the equidistribution of the different state pairs.
摘要:
A method and a circuit for masking a digital word by application of a random bijection, including applying at least one first operation including selecting a non-disjoint subset of the word having its position and size depending on a first random quantity, and assigning to each bit of the subset, the state of the bit having a symmetrical position with respect to the middle of the subset, to obtain a masked digital quantity.
摘要:
A method and an element of ciphering by an integrated processor of data to be stored in a memory, including applying a ciphering algorithm which is a function of a key specific to the integrated circuit and of an initialization vector, and of memorizing at least the ciphered data, the initialization vector depending at least on the address of storage of the data in the memory.