Secret data matching device, computer-readable recording medium storing program for updating secret data, and secret data updating method

摘要

A secret data matching device includes a memory unit for storing a first secret vector obtained by concealing a first data set and a key data using a determination matrix; an obtaining unit for obtaining a second secret vector by concealing a second data set using the determination matrix; a calculating unit for calculating a residue vector which is a residue when the determination matrix is a modulus, from a difference between the first and second secret vectors; a determination unit for determining whether the first and second data sets are approximate based on the residue vector; an extracting unit for extracting the key data from the residue vector when the first data set and the second data set are approximate; a creating unit for generating a third secret vector by combining the key data and the second secret vector; and a storing unit for storing the third secret vector.