Multi signature verification system, electronic signature attaching apparatus, data addition apparatus, and electronic signature verification apparatus

摘要

A multi signature verification system adds new additional data to original data with a signature attached thereto and verifies validity of the original data and the additional data. The system includes an electronic signature attaching apparatus (10) including an electronic signature attaching unit (11) attaching an electronic signature to original data previously created, acquired trapdoor hash value, and identification information, a data addition apparatus, and an electronic signature verification apparatus (30).