SIGNATURE VERIFICATION APPARATUS, SIGNATURE VERIFICATION METHOD, PROGRAM, AND RECORDING MEDIUM

摘要

A signature verification apparatus including a signature acquisition unit configured to acquire a digital signature including first information generated based on a pair of multi-order multivariate polynomials F=(f1, . . . , fm) defined in a ring K, a signature key s which is an element of a set Kn, and a document M and a plurality of pieces of second information for verifying that the first information is generated using the signature key s based on the data M, the pair of multi-order multivariate polynomials F, and vectors y=(f1(s), . . . , fm(s)), and a signature verification unit configured to verify legitimacy of the document M by confirming whether or not the first information is restorable using the plurality of pieces of second information included in the digital signature. The pair of multivariate polynomials F and the vectors y are public keys.

主权项

1. A signature verification apparatus comprising:
a signature acquisition unit configured to acquire a digital signature including first information generated based on a pair of multi-order multivariate polynomials F=(f1, . . . , fm) defined in a ring K and a signature key s which is an element of a set Kn, and a plurality of pieces of second information for verifying that the first information is generated using the signature key s based on the data M, the pair of multi-order multivariate polynomials F, and vectors y=(f1(s), . . . , fm(s)); and a signature verification unit configured to verify legitimacy of the document M by confirming whether or not the first information is restorable using the plurality of pieces of second information included in the digital signature, wherein the pair of multivariate polynomials F and the vectors y are public keys, wherein the signature acquisition unit acquires a predetermined number of the pieces of second information, and wherein the signature verification unit restores the first information sequentially using the acquired predetermined number of pieces of second information and erases the second information unnecessary in a restoring process in an unnecessary stage at which the second information becomes unnecessary.