IJAM: Volume 29, No. 2 (2016)

Abstract. In this manuscript, we propose key-exposure free chameleon hash and chameleon signature scheme in the framework of Guillou-Quisquater (GQ) scheme [#!GQ!#]. This scheme provides more flexible construction of efficient key-exposure free chameleon hash and signature scheme. Moreover, one benefit of consequential the chameleon signature scheme is that the property of message hiding or message realization can be achieved without obstacle by the signer, i.e., the signer can efficiently prove which message was the original one if he desires. The proposed scheme presented in this article improve and extend the corresponding schemes of others several authors. It is also implemented in Mathematica 7.0.