# 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 |