Research On The Strong Designated Verifier Signature Scheme

Normally,the digital signature has the public verifiability;every body can check the legitimacy of the digital signature.However,the signed message(such as: medical privacy and shopping information)sometimes may be involved with some signer's privacy information,if the signature of these messages is verified in public,the privacy information of signer will be leaked,and bringing a bad influence to the signer.The designated verifier signature had solved this problem very well.In the designated verifier signature,the signer(Alice)designates a reliable verifier to verify the signature's validity.the designated verifier(Bob)cannot prove the validity of signature to any third party,and also cannot make any third party believe that the signature is generated by the signer,as the designated verifier also can generate a valid signature of this message.To avoid the signature information being intercepted by intermediaries,the strong designated verifier signature(SDVS)was proposed,it refer to only the one who owns the designated verifier's private key can verify the signature's correctness,and the designated verifier can also simulate a signature,which has same distribution with the original signature.The strong designated verifier signature not only can ensure the correction of signature,but also can protect the signer's privacy.Hence,the strong designated verifier signature has an important effect in protecting the privacy of the signer.This article will carry on the research from three aspects: the non-delegatability of the signature power;the heterogeneous strong designated verifier signature;the certificateless SDVPS with resisting collusion attacks,and achieve three aspects result as follows:1.For the flaws of dissatisfing the non-delegatablity and strongness in the non-delegatable strong designated verifier signature scheme proposed by Zhang et al,an improved strong designated verifier signature scheme with non-delegatablity was put forward.The improved scheme satisfies the strongness and the non-delegatablity.2.Inspired by the thought of heterogeneous signcryption,a heterogeneous bi-directional strong designated verifier signature scheme was proposed,namely the strong designated verifier signature scheme was carried out between the public key infrastructure(PKI)and the identity-based cryptography(IBC)two sets cryptographic systems.The proposed scheme not only satisfied the security requirements of strong designated verifier signature scheme,but didn't include the non-delegatability.3.Analyzed the security of the certificateless proxy signature scheme which was proposed by Xiaohong Liu,and found that it was vulnerable to suffer from the malicious KGC's attack,the collusion attack between original signer and KGC,and the collusion attack between proxysigner and KGC.To get over the above flaws,an improved certificateless proxy signature scheme was proposed.and combining the certificateless proxy signature with the idea of strong designated verifier signature to propose a certificateless strong designated verifier proxy signature scheme.The security analysis showed that the proposed scheme could withstand two types of enemy attacks and the collusion attack,and it also satisfied the security requirements of strong designated verifier signature.