ENCODED TEXT CHECKING SYSTEM, METHOD, AND PROGRAM

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.