MULTIPLE-SIGNATURE MANAGEMENT DEVICE, MULTIPLE-SIGNATURE GENERATION DEVICE, MULTIPLE-SIGNATURE MANAGEMENT PROGRAM, AND MULTIPLE-SIGNATURE GENERATION PROGRAM

摘要

PROBLEM TO BE SOLVED: To reduce a region needed for generation and verification processing for an electronic signature and to easily verify the electronic signature even when a key for the electronic signature becomes unnecessary or when the key needs to be updated. SOLUTION: A multiple signature device which manages multiple signatures generated by a plurality of signers for inputted document data is equipped with a decision section 104 which decides whether signature information of a specified signer is included and a signature erasure section 104 which erases the sign information of the specified signer from the multiple signatures based upon intermediate information generated by a hash function H from a document during the signature generation by the specified signer when it is decided that the signature information of the specified signer is included among the multiple signatures. COPYRIGHT: (C)2006,JPO&NCIPI