基于格的多授权密文属性加密方案

Multi-authority ciphertext-policy attributed-based encryption scheme from lattice

在综合分析现有基于密文策略属性加密方案的基础上,针对现有密文策略属性加密方案中单授权中心负担过重,以及基于传统BDH(bilinear Diffie-Hellman)困难假设的属性加密方案不能抵抗量子攻击的问题,结合格理论构造一个新的多授权中心密文属性基加密方案。该方案可实现多授权中心对用户属性的分散管理,方案使用格上的抽样算法为用户生成密钥,采用线性秘密共享方案来实现属性访问控制策略,支持“与、或与门限”运算。矩阵形式可以支持格上的并行算法,算法的效率更高,安全性证明规约至判定性带误差学习问题的难解性,安全性更满足云环境的要求。

Based on a comprehensive analysis of existing encryption schemes based on ciphertext strategy attributes,the existing ciphertext strategy attribute encryption schemes are bottlenecked by a single authorization center,and an attribute encryption scheme based on the difficult assumption of traditional BDH(bilinear Diffie-Hellman)that cannot resist quantum attacks.This paper combined with the lattice theory to construct a new multi-authorization center ciphertext attribute-based encryption scheme.The scheme could achieve decentralized management of user attributes by the multi-attribute authorization center.The scheme used the sampling algorithm on the grid to generate keys for users,adopted linear encoded sharing technology to achieve the attribute access control strategy,supported“and,or and threshold”operations.The form could support parallel algorithms on the grid,which made algorithm more efficient.Security proves the intractability of learning problems with inherent errors from the protocol to the decision,which better meets than satisfies the requirements for cloud environment.