基于子分组的身份基多重签名方案

Robust Subgroup ID-based Multi-signature Scheme

目前应用于共识机制场景下的多重签名方案默认签名者为诚实实体,因此在恶意节点存在时无法保证签名安全有效。为了结合身份基密码体制与多重签名的优势,并提高多重签名在共识机制应用中对抗场景下的鲁棒性,文中提出了一种基于子分组的身份基多重签名方案。该签名方案中由不固定的随机子分组合作生成代表整个群组的多重签名,并且在签名聚合前须验证所有子分组签名的有效性。该方案生成多重签名所需的双线性对运算与子分组成员数量有关,以一定的效率为代价提升了方案的安全性;定义了基于子分组的身份基多重签名的鲁棒性,并给出了对该方案的相应证明;在随机预言模型下,证明了所提方案在适应性选择消息攻击下是不可伪造的,其安全性基于CDH问题的困难假设。

The existing multi-signature scheme applied in the consensus mechanism scenario defaults that the signers are honest entities,so the security and validity of the signature could not be guaranteed when malicious nodes existed.In order to improve the robustness of multi-signature in the typical adversarial scenarios in consensus protocols,this paper proposes an ID-based multi-signature scheme based on the advantages of the ID-based cryptography system.In this signature scheme,non-fixed subgroup generates randomly cooperated to generate multi-signatures representing the entire group,and the validity of all subgroup signatures must be verified before signature aggregation.The bilinear pairings required by this scheme to generate multi-signatures are related to the number of subgroup members,which improve the security of the scheme at the cost of certain efficiency.This paper introduces a notion of robustness for robust subgroup ID-based multi-signatures,and the corresponding proof of the proposed scheme is given.Furthermore,under the random oracle model,relying on the hardness of the computational Diffie-Helman(CDH)problem,the scheme is proved is proved to be unforgeable under adaptive selection message attack.In addition,theoretical analysis and prototype implementation of the signature scheme are carried out,and the experimental results are compared with the performance of relevant signature schemes.