Affiliations: Department of Computer Science and Engineering, Zhangzhou Normal University, Fujian, 363000, P. R. China | State Key Laboratory of Information Security, Institute of Software of Chinese Academy of Sciences, Beijing 100080, P. R. China | Department of Computer Science and Engineering, Shanghai Jiao Tong University, Shanghai 200030, P. R. China | State Key Laboratory of Integrated Service Networks, Xidian University, Xi'an, Shaanxi, 710071, P. R. China, e-mail: zjhuang@stju.edu.cn | Department of Computer Science and Engineering, Shanghai Jiao Tong University, Shanghai 200030, P. R. China, e-mail: kfchen@stju.edu.cn | State Key Laboratory of Integrated Service Networks, Xidian University, Xi'an, Shaanxi, 710071, P. R. China, e-mail: ymwang@xidian.edu.cn
Abstract: This paper introduces a new concept of convertible user designating confirmer partially blind signature, in which only the designated confirmer (designated by the user) and the user can verify and confirm the validity of given signatures and convert given signatures into publicly verifiable ones. We give a formal definition for it and propose a concrete provably secure scheme with a proof of security and a brief analysis of efficiency. Assuming the intractabilities of the Discrete Logarithm Problem and the ROS-Problem, the proposed scheme is unforgeable under adaptive chosen-message attack.
Keywords: cryptography, digital signature, partially blind signature, user designating confirmer signature, convertible
Journal: Informatica, vol. 17, no. 3, pp. 347-362, 2006
