Research On Digital Signatures With Verification Right Control

The digital signature is a special product of electronic information age. It is an effective method to guaranteeing the authenticity, integrity and non-repudiation of electronic information. There is a kind of special digital siganture, which provide special functionality to control the verification rights of the signatures, can be used to protect the secret informaion of signer and named as digital signatures with verification right control. This special digital signature can be used to insure the fairness of information interaction in the opening internet circumstance. Digital signatures with verification right control such as designated verifier signatures, limited verifier signatures and conditionally verifiable signatures are studied in this paper and the main works are as follows:The development of digital signatures with verification right control is described. Especially, the application background, advantages and flaws of some typical schemes such as designated verifier signatures, limited verifier signatures and conditionally verifiable signatures are presented.A new digital signature scheme is proposed, which is named as limited multi-verifier signatures. The new scheme provides the functionality that only one signature computation can limit multiple verifiers to verify the validity of the signature. Therefore, the limitation of only one limited verifier in generic limited verifier signatures schemes is offseted. The new scheme supports denial protocol and the desired security notions are achieved. Moreover, this scheme has higher efficiency than performing generic limited single verifier signatures multiple times.Based on some practice application requirments, another new digital signature scheme is proposed, which is named as limited confederate verifier signatures. The new scheme not only can hide the messege, but also allows that the signature can be verified iff all the designated verifiers cooperate. The siganture generated by this new scheme is short, and the size of the signature does not grow with the number of verifiers. Moreover, the scheme is proved toachieve the desired security request under the random oracle model.