# Kouichi Itoh, Kawasaki JP

## Kouichi Itoh, Kawasaki JP

Patent application number | Description | Published |
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20090003598 | ENCRYPTING APPARATUS FOR COMMON KEY CIPHER - The first route selection device re-arrays a plurality of extended key mask values at random according to the value of a random number generated by a random number generation device. An extended key operation device generates an exclusive logical OR of a plurality of the re-arrayed extended key mask values, a data string representing extended key and an input data string. The second route selection device re-arrays the data string of the exclusive logical OR by performing a re-array conversely with the first route selection device according to the value of the random number. A non-linear conversion device applies non-linear conversion to the re-arrayed data string and outputs a data string masked by a plurality of non-linear conversion mask values. The third route selection device re-arrays the masked data string by performing the same re-array as the first route selection device according to the value of the random number. | 01-01-2009 |

20100031055 | EMBEDDED DEVICE HAVING COUNTERMEASURE FUNCTION AGAINST FAULT ATTACK - A cryptographic processing device, comprising: a storage unit; initial setting unit for setting a value to be stored in the storage unit; Montgomery modular multiplication operation unit for performing a Montgomery modular multiplication operation plural times for a value set by the initial setting unit; and fault attack detection unit for determining whether or not a fault attack occurred for each of at least some parts of the Montgomery modular multiplication operations performed plural times. | 02-04-2010 |

20100183143 | CRYPTOGRAPHIC PROCESSING APPARATUS AND CRYPTOGRAPHIC PROCESSING METHOD - A cryptographic processing apparatus for performing arithmetic operation on an FL function and an FL | 07-22-2010 |

20100183144 | Cipher processing apparatus - A cipher processing apparatus for arithmetic operations of an FO function and an FL function comprising: an FL function operating unit for generating a 2N-bit output based on a first extension key; a partial function operating unit for generating an N-bit output based on second and third extension keys; an N-bit intermediate register for storing an output of the partial operating unit; a 2N-bit first data register for storing data based on the output of the FL function operating unit; and a controller for making the partial function operating unit perform six cycles, inputting an output of the intermediate register to the FL function operating unit, and storing the data based on the output of the FL function operating unit in the first data register, in a first case in which the FL function uses a result of an arithmetic operation of the FO function. | 07-22-2010 |

20100232601 | ELLIPTIC CURVE ARITHMETIC PROCESSING UNIT AND ELLIPTIC CURVE ARITHMETIC PROCESSING PROGRAM AND METHOD - An apparatus for executing cryptographic calculation on the basis of an elliptic point on an elliptic curve includes: a memory for storing a first value including a plurality of digits; and a processor for executing a process including: obtaining a second value representing a point on the elliptic curve; calculating output values by using a predetermined equation, each digit of the first value, and the second value; determining whether at least one of the second value and the output values indicates a point of infinity; terminating the calculation when at least one of the second value and the output values indicates the point at infinity; and completing calculation when both the second value and the output values do not indicate the point at infinity, so as to obtain a result of the cryptographic calculation. | 09-16-2010 |

20100232603 | DECRYPTION PROCESSOR AND DECRYPTION PROCESSING METHOD - A decryption processor for calculating a plaintext through decryption of a ciphertext c includes, a first part that calculates m′ | 09-16-2010 |

20100278332 | DATA CONVERSION FUNCTION PROCESSOR | 11-04-2010 |

20100278340 | ENCRYPTION DEVICE, ENCRYPTION METHOD AND STORAGE MEDIUM STORING ITS PROGRAM - When processing a data conversion function of a MISTY structure, such as the FO function of MISTY1, the logical calculation result t | 11-04-2010 |

20110007894 | CRYPTOGRAPHIC PROCESSING METHOD, COMPUTER READABLE STORAGE MEDIUM, AND CRYPTOGRAPHIC PROCESSING DEVICE - stores, in | 01-13-2011 |

20110013769 | ENCRYPTION APPARATUS HAVING COMMON KEY ENCRYPTION FUNCTION AND EMBEDDED APPARATUS - A common key block encryption apparatus for performing a nonlinear transformation with a multiplication executed in a binary field or a composite field includes a computing unit to execute a computation other than the nonlinear transformation with fixed value masked input data obtained by XORing input data with a fixed mask value, an XOR operation circuit to transform all input data into fixed value masked input data by XORing the input data with a fixed mask value and to transform the data into random value masked input data by XORing the input data with a random mask value in the multiplication, a multiplier to execute a multiplication based on the random value masked input data output from the XOR operation circuit, and a random value mask-to-fixed mask value transformation circuit to again transform the random value masked output data into fixed value masked output data and to output the data. | 01-20-2011 |

20110013770 | ENCRYPTING METHOD HAVING COUNTERMEASURE FUNCTION AGAINST POWER ANALYZING ATTACKS - Based on an encrypting method for performing an exponential remainder calculation y=a | 01-20-2011 |

20110075836 | METHOD AND APPARATUS FOR ELLIPTIC CURVE CRYPTOGRAPHIC PROCESSING - An apparatus includes a data storage to store a window table storing a table value with an index value mapped to the table value, the index value having same number of bits as a window width, the table value being a sum of a basic table value and a non-zero table correction value, the basic table value being obtained by multiplying a point G on an elliptic curve. An arithmetic processor generates the index value by reading from a scalar value at a bit position assigned to each bit of the window with the window being shifted, reads the table value from the window table according to the index value, and performs a doubling operation and an addition operation using the read table value. A corrector performs a correction on arithmetic results with a specific correction value responsive to the table correction value. | 03-31-2011 |

20110176673 | Encrypting apparatus - An encrypting apparatus includes a digest part using a SHA-2 algorithm of which a basic unit of operation is 32*Y (Y=1 or 2) bits. The digest part includes a shift register including a series of registers, and a predetermined number of adders performing an addition operation based on data stored in the shift register. The shift register includes a (32*Y)/X-bit register, where X=2 | 07-21-2011 |

20130022197 | RANDOM NUMBER GENERATOR, ENCRYPTION DEVICE, AND AUTHENTICATION DEVICE - A random number generator includes an exclusive-OR circuit, a random number determiner, and a random number generation instruction inhibitor. The exclusive-OR circuit obtains an exclusive-OR of outputs from a number of digital circuits. The random number determiner determines whether or not an output generated according to an instruction to generate random numbers is a random number for each of the digital circuits. The random number generation instruction inhibitor inhibits an instruction to generate random numbers to be provided to the digital circuits whose output generated according to the instruction is determined to be not a random number by the random number determiner. | 01-24-2013 |

20130039486 | CRYPTOGRAPHIC PROCESSING DEVICE AND CRYPTOGRAPHIC PROCESSING METHOD - A cryptographic processing device includes a private key storage unit which stores a private key d for elliptic curve cryptography, a random number generation unit which generates a b-bit random value s, and a processing unit. A bit string D is the private key d or a bit string obtained by modifying the private key d in such a way that a value of a most significant bit is 0, and a relation u=mk+b holds true for a length u of the bit string D, a window size k, and a positive integer m. The processing unit determines a signed k-bit window value w[i] corresponding to each i where 0≦i≦(m−1), a signed b-bit random value s[i] corresponding to each i, and a correction value g. The processing unit determines the above values under a certain constraint condition, while determining each random value s[i] to be +s or −s. | 02-14-2013 |

20130138710 | INDIVIDUAL-SPECIFIC INFORMATION GENERATION APPARATUS AND INDIVIDUAL-SPECIFIC INFORMATION GENERATION METHOD - The generation of individual-specific information having a good reliability and uniqueness is made possible with a little circuit scale. For this purpose, in an individual-specific information generation apparatus, a plurality of digital circuits are in the same circuit configuration. Each of the digital circuits outputs a fixed or a random number output value individually without their output with respect to a certain input being determined unambiguously among the digital circuits. In each of the digital circuit, an order is defined in advance. A random number judgment unit judges whether the output value is a random value or fixed, for each of the plurality of digital circuits. An individual-specific information generation unit generates the individual-specific information based on information of the order defined in the digital circuit judged by the random number judgment unit as having a fixed output value among the plurality of digital circuits and the output value. | 05-30-2013 |

20130287209 | ENCRYPTION PROCESSING DEVICE AND METHOD - A constant multiplier inputs a base and a modulo n, performs modular exponentiation modulo n with a prescribed constant as the exponent and with base a, and outputs the result of this calculation as base b. A personal key converter inputs a personal key d and calculates a personal key d′ as the quotient when d is divided by the prescribed constant. A correction key generator generates a correction key d″ as the remainder of the aforementioned division. A first modular exponentiation unit performs modular exponentiation base b with d′ as the exponent. A second modular exponentiation unit performs modular exponentiation base a with d″ as the exponent, and outputs a correction value. A correction calculation unit multiplies the outputs of the first and second modular exponentiation units and outputs the result as the encryption processing result. | 10-31-2013 |

20140016772 | ENCRYPTING DEVICE, ENCRYPTING METHOD, AND RECORDING MEDIUM - k bits from the least significant bit of the current secret key are retrieved, obtaining a binary window sequence. A binary bit string of concatenation of the random number to the more significant bits of the window sequence is obtained if the most significant bit of the window sequence is 0, subtracting a bit string from the current secret key to obtain a new secret key, or the bit string of a complement of the base number for the window sequence in binary system is calculated if the most significant bit of the window sequence is 1, obtaining a bit string by adding a minus sign to a bit string obtained by concatenating the random number to the more significant bits of the bit string, subtracting the bit string from the current secret key to obtain a new secret key. | 01-16-2014 |

20140019467 | METHOD AND APPARATUS FOR PROCESSING MASKED DATA - A disclosed method includes: generating a predetermined number of sets, wherein each of the sets includes n mask values and n is the number of attributes to be masked in a database; selecting, for each record of a plurality of records, which includes attribute values of the attributes to be masked, one set of the predetermined number of sets; and performing, for each record of the plurality of records, a predetermined operation for the selected one set of the n mask values and the attribute values of the attributes to be masked in the record to generate masked data for the plurality of records. | 01-16-2014 |

20140037089 | ENCRYPTION PROCESSING DEVICE AND METHOD - An encryption processing device includes: a memory configured to store a first secret key and a first agitation value operated with the first secret key; and a processor coupled to the memory and configured to: receive a first random number, generate a second agitation key based on the first secret key and the first agitation value, generate a first encryption information based on the second secret key and the first random number, update the first agitation value stored in the memory, and output the first agitation value and the first encryption information. | 02-06-2014 |

20140164785 | ENCRYPTION PROCESSING DEVICE AND AUTHENTICATION METHOD - An encryption processing device includes a memory configured to store a common key, and a processor configured to generate a random number which is an integer, to perform a bit transposition on the common key, the bit transposition being determined at least by the random number, to transmit the random number to another encryption processing device and to receive a response from the other encryption processing device, the response obtained by encryption using a common key stored in the other encryption processing device and a second randomized key generated by performing the bit transposition determined by the random number; and to authenticate the other encryption processing device either by comparing the response with the random number by decrypting the response with the common key, or by comparing the random number with the response by encrypting the random number with the common key. | 06-12-2014 |

20140181524 | AUTHENTICATION METHOD, AUTHENTICATION SYSTEM, AND AUTHENTICATION CHIP USING COMMON KEY CRYPTOGRAPHY - A method is disclosed for authenticating, by a processor that controls a parent device, a child device includes: authenticating the child device by making a comparison between a value obtained by operating, for a first response value, a third transform function, which is decided based on a number of a difference between the value set in an authentication chip of the parent device and the value set in an authentication chip of the child device, and the second response value, wherein a first and a second response values are obtained by operating a first and a second transform functions for output values generated by operating an encryption function for performing encryption for secret keys in authentication chips of the parent device and the child device, respectively. | 06-26-2014 |