Abstract: Concerning the signature security problem in reality, based on the Waters'technology, a universal designated verifier signcryption scheme in the standard model was proposed. Signcryption is a cryptographic primitive which performs encryption and signature in a single logical step. Universal designated verifier signature allowed a signature holder who had a signature of a signer, to convince a designated verifier that he was in possession of a signer's signature, while the verifier could not transfer such conviction to anyone else, only allowed the designated verifier to verify the existence of the signature. The scheme by combining universal designated verifier and signcryption eliminated the signer and signture holders for signature transmission required for a secure channel. Under the assumption of Computational Bilinear Diffie-Hellman (CBDH) problem, the scheme was proved to be safe. Compared with the existing schemes, the proposed scheme has better computational efficiency.

Key words: signcryption, universal designated verifier, standard model, bilinear pairings

摘要： 针对现实中签名的安全问题，提出了基于Waters技术的标准模型下安全的广义指定验证者签密方案。签密能够在一个逻辑步骤内同时完成加密和签名的功能。在广义指定验证者签名中，签名持有者即其拥有签名者的签名，能够确认一个指定验证者使其拥有这个签名，而指定验证者不能转移这种认定给其他任何人，仅指定的验证者能够验证签名的存在性。该方案通过广义指定验证者和签密的结合，消除了签名者和签名持有者在签名传输时所需的安全通道。在计算性线性Diffie-Hellman问题假设下，该方案被证明是安全的。和现有的方案相比，所提方案具有较高的计算效率。

关键词: 签密, 广义指定验证者, 标准模型, 双线性对