ENCRYPTED DATA VERIFICATION SYSTEM, METHOD AND RECORDING MEDIUM

摘要

The present invention makes it possible, in encrypted data verification, to avoid the leaking of information related to the original plaintext, thereby ensuring safety. The system of the present invention is provided with: means (103 in FIG. 1) for generating first and second auxiliary data for verifying whether or not the Hamming distance of a plaintext between a first encrypted data in which input data is encrypted and is recorded in a storage device, and a second encrypted data obtained by encrypting input data of a target to be checked is equal to or less than a predetermined value; and means (402 and 403 in FIG. 1) for taking the difference between the first encrypted data recorded in the storage device, and the second encrypted data, and determining, using the first and second auxiliary data, whether or not the Hamming distance of the plaintext corresponding to the difference between the first encrypted data and the second encrypted data is equal to or less than the predetermined value.

主权项

1. An encrypted data verification system comprising:
an auxiliary data generation apparatus configured to generate first and second auxiliary data that are used to verify, that a Hamming distance between a plaintext of a first encrypted data which is encrypted from input data and registered to a storage apparatus, and a plaintext of a second encrypted data which is encrypted from input data of a target to be verified, is a predetermined certain value or less, for the first encrypted data and the second encrypted data respectively; and a verification apparatus configured to obtain a difference between the first encrypted data that is registered to the storage apparatus and the second encrypted data that is obtained by encrypting the input data of the target to be verified, and determine whether or not the Hamming distance of the plaintexts, which corresponds to the difference between the first encrypted data and the second encrypted data, is the predetermined certain value or less, using the first and second auxiliary data.