In this paper,we first propose a memristive chaotic system and implement it by circuit simulation.The chaotic dynamics and various attractors are analysed by using phase portrait,bifurcation diagram,and Lyapunov expon...In this paper,we first propose a memristive chaotic system and implement it by circuit simulation.The chaotic dynamics and various attractors are analysed by using phase portrait,bifurcation diagram,and Lyapunov exponents.In particular,the system has robust chaos in a wide parameter range and the initial value space,which is favourable to the security communication application.Consequently,we further explore its application in image encryption and present a new scheme.Before image processing,the external key is protected by the Grain-128a algorithm and the initial values of the memristive system are updated with the plain image.We not only perform random pixel extraction and masking with the chaotic cipher,but also use them as control parameters for Brownian motion to obtain the permutation matrix.In addition,multiplication on the finite field GF(2^(8))is added to further enhance the cryptography.Finally,the simulation results verify that the proposed image encryption scheme has better performance and higher security,which can effectively resist various attacks.展开更多
云存储为用户的数据管理带来了极大便捷,已成为数字经济的重要组成部分.然而,复杂多样的网络环境和不完全可信的第三方对用户隐私造成极大威胁.为保护用户隐私,通常先加密数据后存储,但传统加密技术生成的密文阻碍了后续数据检索.公钥...云存储为用户的数据管理带来了极大便捷,已成为数字经济的重要组成部分.然而,复杂多样的网络环境和不完全可信的第三方对用户隐私造成极大威胁.为保护用户隐私,通常先加密数据后存储,但传统加密技术生成的密文阻碍了后续数据检索.公钥可搜索加密(public-key encryption with keyword search,PEKS)技术在保障数据加密的同时,可提供保密检索功能,但由于常用关键词数量较少,传统PEKS方案易遭受关键词猜测攻击.公钥认证可搜索加密(public-key authenticated encryption with keyword search,PAEKS)在PEKS的基础上引入认证技术,可进一步提高安全性.然而,现有PAEKS方案大多基于国外密码算法设计,不符合我国密码技术自主创新的发展需求.基于国密SM9提出SM9-PAEKS方案,通过重新设计算法结构,将耗时运算转移至资源丰富的云端服务器,有效提升用户端检索效率.并在随机谕言模型下基于q-BDHI和Gap-q-BCAA1安全假设证明所提方案的安全性.最后理论分析和实验结果表明,与同类方案中通信代价最优的方案相比,SM9-PAEKS在仅增加96字节通信代价的情况下,总计算开销可至少降低约59.34%,其中关键词陷门生成的计算开销降低尤其显著,约为77.55%.有助于丰富国密算法的应用,同时可为云存储中数据加密与检索提供理论与技术支撑.展开更多
基金This work was supported by the National Natural Science Foundation of China(61203004)the Natural Science Foundation of Heilongjiang Province(F201220)the Heilongjiang Provincial Natural Science Foundation of Joint Guidance Project(LH2020F022).
文摘In this paper,we first propose a memristive chaotic system and implement it by circuit simulation.The chaotic dynamics and various attractors are analysed by using phase portrait,bifurcation diagram,and Lyapunov exponents.In particular,the system has robust chaos in a wide parameter range and the initial value space,which is favourable to the security communication application.Consequently,we further explore its application in image encryption and present a new scheme.Before image processing,the external key is protected by the Grain-128a algorithm and the initial values of the memristive system are updated with the plain image.We not only perform random pixel extraction and masking with the chaotic cipher,but also use them as control parameters for Brownian motion to obtain the permutation matrix.In addition,multiplication on the finite field GF(2^(8))is added to further enhance the cryptography.Finally,the simulation results verify that the proposed image encryption scheme has better performance and higher security,which can effectively resist various attacks.
文摘云存储为用户的数据管理带来了极大便捷,已成为数字经济的重要组成部分.然而,复杂多样的网络环境和不完全可信的第三方对用户隐私造成极大威胁.为保护用户隐私,通常先加密数据后存储,但传统加密技术生成的密文阻碍了后续数据检索.公钥可搜索加密(public-key encryption with keyword search,PEKS)技术在保障数据加密的同时,可提供保密检索功能,但由于常用关键词数量较少,传统PEKS方案易遭受关键词猜测攻击.公钥认证可搜索加密(public-key authenticated encryption with keyword search,PAEKS)在PEKS的基础上引入认证技术,可进一步提高安全性.然而,现有PAEKS方案大多基于国外密码算法设计,不符合我国密码技术自主创新的发展需求.基于国密SM9提出SM9-PAEKS方案,通过重新设计算法结构,将耗时运算转移至资源丰富的云端服务器,有效提升用户端检索效率.并在随机谕言模型下基于q-BDHI和Gap-q-BCAA1安全假设证明所提方案的安全性.最后理论分析和实验结果表明,与同类方案中通信代价最优的方案相比,SM9-PAEKS在仅增加96字节通信代价的情况下,总计算开销可至少降低约59.34%,其中关键词陷门生成的计算开销降低尤其显著,约为77.55%.有助于丰富国密算法的应用,同时可为云存储中数据加密与检索提供理论与技术支撑.
