SYSTEM, METHOD AND PROGRAM FOR VERIFYING EXISTENCE OF EACH EXPONENTIAL COEFFICIENT OF POWER-RESIDUE PRODUCT OF PROBABILITY DISCLOSURE KEY CRYPTOGRAM IN SECTION

摘要

PROBLEM TO BE SOLVED: To verify that the value of each exponential coefficient of a power- residue product of a probability disclosure key cryptogram is present in a specified range while hiding the value of the exponential coefficient.;SOLUTION: An input part 201 inputs a probability disclosure key ciphering type disclosure key 205, a variable 206 for determining the upper limit value and lower limit value of a specified section, a cryptogram row 207, an exponential coefficient row 208, and a safe variable 209. An arithmetic processing part 202 generates a power-residue product 221 on the basis of the exponential coefficient row 208 of the cryptogram row 207 and verification sentences 222 to 225 for judging whether the values of respective exponential coefficients exist in the section specified by the variable 206 or not on the verification side without eliminating the difficulty of deciphering the value of the row 208 used for the generation of the product 221. An output part 203 outputs a verification message 204 containing the product 221 and the verification sentences 222 to 225.;COPYRIGHT: (C)2003,JPO