| 摘要 |
PROBLEM TO BE SOLVED: To provide an arithmetic device for cipher that has resistance to simple electric power analysis of selection document type of (n-1) input type, and has high arithmetic efficiency. SOLUTION: An input section 11 inputs a message M as the base of modulo exponentiation calculation, private power (d), and modulus (n). A preprocessing section 12 multiplies the message M itself to determine conversion data. An arithmetic section 2 for cipher sets the conversion data as an arithmetic object, and performs the modulo exponentiation calculation under the modulus (n) by right-face arithmetic procedure based on the power (d) except the lowest bit. A post-processing section 13 performs modulo multiplication calculation of the arithmetic result and the message M under the modulus (n) when LSB of the (d) is 1, and performs the same modulo multiplication calculation as a dummy calculation when the LSB of the (d) is 0. An output section 14 outputs, as a final result, the arithmetic result of the post-processing section 13 (when the LSB of the (d) is 1) or the arithmetic result of the arithmetic section 2 for cipher (when the LSB of the (d) is 0). COPYRIGHT: (C)2010,JPO&INPIT
|
