Abstract: A ciphertext comparison method according to an embodiment is performed by a processor in a computing apparatus, and the method includes an operation of segmenting a first ciphertext and a second ciphertext into m part bitstreams (in this instance, m is a natural number satisfying 1<m), respectively; an operation of extracting a value corresponding to a j?1th part bitstream (in this instance, j=i+1, i is a natural number satisfying 0?i?m?1) of the first ciphertext and a j?1th part bitstream of the second ciphertext, as a jth intermediate value between a first value and a second value in a first lookup table including the first value and the second value of which Hamming weights are identical; an operation extracting a value corresponding to the jth intermediate value and a j?1th result value, as a jth result value between a third value and a fourth value in a second lookup table including the third value and the fourth value of which Hamming weights are identical; and in a case of j?m, an operation of repea

Abstract: The present disclosure according to at least one embodiment provides a method of processing operations of a polynomial-based security algorithm, the method being performed by a computing system. The method comprises identifying a plurality of operations using secret information in the polynomial-based security algorithm, generating a random index to be applied to the identified operations, and performing the operations using the random index.

Abstract: Disclosed is a fault injection attack method including determining a trigger start point in time based on an input signal for a crypto device; determining a trigger end point in time based on an output signal of the crypto device; setting a trigger based on the trigger start point in time and the trigger end point in time; and performing a fault injection attack based on the set trigger.

Abstract: A method for preventing side-channel attack according to an embodiment includes generating an order table which includes a position index value for each bit value of a bit string that is secret information to be generated through a decryption algorithm of an Nth Degree Truncated Polynomial Ring Units (NTRU) LPRime algorithm, shuffling a sort order of the position index value for the each bit value in the order table based on a random number, determining a generation order for the each bit value according to the sort order of the position index value for the each bit value in the order table, and generating the secret information through the decryption algorithm. The secret information is generated by generating the each bit value according to the determined generation order.

Abstract: A method for performing a matrix multiplication operation being secure against side-channel attacks according to one embodiment, which is performed by a computing device comprising one or more processors and a memory storing one or more programs to be executed by the one or more processors, includes shuffling an order of execution of multiplication operations between elements of a first matrix and elements of a second matrix for a matrix multiplication operation between the first matrix and the second matrix; and performing the matrix multiplication operation based on the shuffled order of execution.

Abstract: Disclosed is a fault injection attack method including determining a trigger start point in time based on an input signal for a crypto device; determining a trigger end point in time based on an output signal of the crypto device; setting a trigger based on the trigger start point in time and the trigger end point in time; and performing a fault injection attack based on the set trigger.

Abstract: A method for preventing side-channel attack according to an embodiment includes generating an order table which includes a position index value for each bit value of a bit string that is secret information to be generated through a decryption algorithm of an Nth Degree Truncated Polynomial Ring Units (NTRU) LPRime algorithm, shuffling a sort order of the position index value for the each bit value in the order table based on a random number, determining a generation order for the each bit value according to the sort order of the position index value for the each bit value in the order table, and generating the secret information through the decryption algorithm. The secret information is generated by generating the each bit value according to the determined generation order.

Abstract: A method for performing a matrix multiplication operation being secure against side-channel attacks according to one embodiment, which is performed by a computing device comprising one or more processors and a memory storing one or more programs to be executed by the one or more processors, includes shuffling an order of execution of multiplication operations between elements of a first matrix and elements of a second matrix for a matrix multiplication operation between the first matrix and the second matrix; and performing the matrix multiplication operation based on the shuffled order of execution.

Abstract: Provided is a scalar multiplication method unified with a simple power analysis (SPA) resistant left-to-right recording in a crypto system based on an elliptic curve and a pairing. The scalar multiplication method includes: recording an L-digit secret key k? from a radix-r n-digit secret key k by comparing two successive elements with each other from the most significant digit with duplication allowed in order to generate the L-digit secret key k?; and performing scalar multiplication between the secret key k and a point P on an elliptic curve to output a scalar multiplication value Q=kP using the secret key k?.