| 摘要 |
The present invention makes it possible, in encrypted text matching, to avoid information leakage with regard to a plain source text and to ensure security. In the present invention, a system includes: a means for generating auxiliary data 1 and 2 for verifying that an encrypted text 1, which is input data that is encrypted and recorded in a storage device, and an encrypted text 2, which is input data to be matched that has been encrypted, match using the Hamming distance of the plain texts; and a means for unidirectionally converting at least one portion of the auxiliary data 2, unidirectionally converting intermediate data generated on the basis of the auxiliary data 1 and the difference between the encrypted text 1 and the encrypted text 2, and using the auxiliary data 2 and the results of the unidirectional conversion of the intermediate data to determine whether or not the Hamming distance of the plain texts corresponding to the difference between the encrypted text 1 and the encrypted text 2 is at or below a predetermined designated value. |
