雾计算中细粒度属性更新的外包计算访问控制方案

针对基于密文策略的属性加密(CP-ABE)在低时延需求较高的雾计算环境中,存在加解密开销大、属性更新效率低的问题,提出了一种雾计算中细粒度属性更新的外包计算访问控制方案,使用模加法一致性秘密(密钥)分享技术构建访问控制树,将加解密计算操作外包给雾节点,降低用户加解密开销;结合重加密机制,在雾节点建立组密钥二叉树对密文进...     

Secure personal data sharing in cloud computing using attribute-based broadcast encryption

The ciphertext-policy (CP) attribute-based encryption (ABE) (CP-ABE) emergings as a promising technology for allowing users to conveniently access data in cloud computing. Unfortunately, it suffers from several drawbacks such as decryption overhead, user revocation and privacy preserving. The authors proposed a new efficient and privacy-preserving attribute-based broadcast encryption (BE) (ABBE) named EP-ABBE, that can reduce the decryption computation overhead by partial decryption, and protect user privacy by obfuscating access policy of ciphertext and user's attributes. Based on EP-ABBE, a secure and flexible personal data sharing scheme in cloud computing was presented, in which the data owner can enjoy the flexibly of encrypting personal data using a specified access policy together with an implicit user index set. With the proposed scheme, efficient user revocation is achieved by dropping revoked user's index from the user index set, which is with very low computation cost. Moreover, the privacy of user can well be protected in the scheme. The security and performance analysis show that the scheme is secure, efficient and privacy-preserving.     

Attribute-Based Access Control with Efficient and Secure Attribute Revocation for Cloud Data Sharing Service

Nowadays, there is the tendency to outsource data to cloud storage servers for data sharing purposes. In fact, this makes access control for the outsourced data a challenging issue. Ciphertext-policy attribute-based encryption (CP-ABE) is a promising cryptographic solution for this challenge. It gives the data owner (DO) direct control on access policy and enforces the access policy cryptographically. However, the practical application of CP-ABE in the data sharing service also has its own inherent challenge with regard to attribute revocation. To address this challenge, we proposed an attribute-revocable CP-ABE scheme by taking advantages of the over-encryption mechanism and CP-ABE scheme and by considering the semi-trusted cloud service provider (CSP) that participates in decryption processes to issue decryption tokens for authorized users. We further presented the security and performance analysis in order to assess the effectiveness of the scheme. As compared with the existing attribute-revocable CP-ABE schemes, our attribute-revocable scheme is reasonably efficient and more secure to enable attribute-based access control over the outsourced data in the cloud data sharing service.     

属性可撤销且密文长度恒定的属性基加密方案

密文策略属性基加密（ciphertext-policy attribute-based encryption,CP-ABE）类似于基于角色访问控制,可以为云存储系统提供灵活细粒度的访问控制.但大多数CP-ABE方案中,密文长度与访问策略复杂度成正相关,系统属性同时被多个用户共享而导致属性难以被撤销.针对上述问题,本文提出一种支持属性撤销且密文长度恒定的属性基加密方案.该方案中每个用户的属性群密钥不能通用,可以有效抵抗撤销用户与未撤销用户的合谋攻击.为减少属性授权机构和数据拥有者的计算负担,属性撤销过程所需的计算量外包给数据服务管理者;同时该方案采用支持多值属性和通配符的"AND"门策略,实现了密文长度恒定.所提方案基于决策性q-BDHE（q-bilinear Diffie-Hellman exponent）假设对方案进行了选择明文攻击的安全性证明.最后对方案进行了理论分析与实验验证,分析结果表明本文方案可以有效抵制用户合谋攻击,增加了方案的安全性.同时所提方案在功能和计算效率方面具有一定优势,适用于实际应用情况.     

Data sharing scheme supporting secure outsourced computation in wireless body area network

How to effectively protect the security of data sharing in WBAN was a key problem to be solved urgently.The traditional CP-ABE mechanism had a 〝one to many〝 data security communication function which was suitable for access control in WBAN,but it had high computational complexity and did not support attribute revocation.Fully considering of limitations on computation and storage of sensor nodes and dynamic user attribute in WBAN,a CP-ABE scheme was proposed which was provably secure against CPA under the standard model and supported attributes revocation,outsourced encryption and decryption.Compared with the proposed schemes,the computation burden on senor nodes is greatly reduced and the user's attribution can be revoked immediately and fine grained while meeting the demand of its security in the proposed scheme.     

云存储环境下的密文安全共享机制

With the convenient of storing and sharing data in cloud storage environment,the concerns about data security arised as well.To achieve data security on untrusted servers,user usually stored the encrypted data on the cloud storage environment.How to build a cipertext-based access control scheme became a pot issue.For the access control problems of ciphertext in cloud storage environment,a CP-ABE based data sharing scheme was proposed.Novel key generation and distribution strategies were proposed to reduce the reliance on a trusted third party.Personal information was added in decryption key to resistant conclusion attacks at the same time.Moreover,key revocation scheme was proposed to provide the data backward secrecy.The security and implement analysis proves that proposed scheme is suit for the real application environment.     

具有隐私保护的细粒度智能家居远程数据安全更新方案

针对现存智能家居软件更新方案中存在的粗粒度访问控制、单点服务失效、用户解密效率低下等问题,该文提出一种具有隐私保护的细粒度智能家居远程数据安全更新方案。该方案通过属性基加密技术实现了细粒度访问控制,并结合区块链和星际文件系统(IPFS)技术对数据进行存储。通过对访问策略进行隐藏,构造出一种策略隐藏的密文策略基于属性加密(CP-ABE)算法,进一步保护了用户的隐私。此外,通过设计面向轻量级用户的外包解密算法,所提方案有效减轻了轻量级用户的计算负担,并结合区块链和智能合约技术实现了外包解密过程的公平支付。最后,基于判定的双线性迪菲赫尔曼 (DBDH)假设,证明了所提方案是选择明文攻击下的不可区分 (IND-CPA)安全的。仿真实验结果表明,所提方案与现有方案相比终端用户解密成本和通信开销明显降低。     

Efficient revocable attribute-based encryption scheme

In the existing solutions,the time-based scheme is difficult to achieve immediate revocation,and the third-party-based scheme often requires re-encryption,which needs large amount of calculation and doesn’t apply to mas-sive data.To solve the problem,an efficient and immediate CP-ABE scheme was proposed to support user and attribute lev-els revocation.The scheme was based on the classic LSSS access structure,introducing RSA key management mechanism and attribute authentication.By means of a semi-trusted third party,the user could be authenticated before decryption.Com-pared with the existing revocation schemes,The proposed scheme didn’t need the user to update the key or re-encrypt the ciphertext.The semi-trusted third party wasn’t required to update the RSA attribute authentication key.The scheme greatly reduced the amount of computation and traffic caused by revocation,while ensuring anti-collusion attacks and forward and backward security.Finally,the security analysis and experimental simulation show that the scheme has higher revocation ef-ficiency.     

云存储环境下无密钥托管可撤销属性基加密方案研究

属性基加密因其细粒度访问控制在云存储中得到广泛应用。但原始属性基加密方案存在密钥托管和属性撤销问题。为解决上述问题,该文提出一种密文策略的属性基加密方案。该方案中属性权威与中央控制通过安全两方计算技术构建无密钥托管密钥分发协议解决密钥托管问题。通过更新属性版本密钥的方式达到属性级用户撤销,同时通过中央控制可以实现系统级用户撤销。为减少用户解密过程的计算负担,将解密运算过程中复杂对运算外包给云服务商,提高解密效率。该文基于q-Parallel BDHE假设在随机预言机模型下对方案进行了选择访问结构明文攻击的安全性证明。最后从理论和实验两方面对所提方案的效率与功能性进行了分析。实验结果表明所提方案无密钥托管问题,且具有较高系统效率。     

Fine-grained data access control for distributed sensor networks

Distributed sensor networks are becoming a robust solution that allows users to directly access data generated by individual sensors. In many practical scenarios, fine-grained access control is a pivotal security requirement to enhance usability and protect sensitive sensor information from unauthorized access. Recently, there have been proposed many schemes to adapt public key cryptosystems into sensor systems consisting of high-end sensor nodes in order to enforce security policy efficiently. However, the drawback of these approaches is that the complexity of computation increases linear to the expressiveness of the access policy. Key-policy attribute-based encryption is a promising cryptographic solution to enforce fine-grained access policies on the sensor data. However, the problem of applying it to distributed sensor networks introduces several challenges with regard to the attribute and user revocation. In this paper, we propose an access control scheme using KP-ABE with efficient attribute and user revocation capability for distributed sensor networks that are composed of high-end sensor devices. They can be achieved by the proxy encryption mechanism which takes advantage of attribute-based encryption and selective group key distribution. The analysis results indicate that the proposed scheme achieves efficient user access control while requiring the same computation overhead at each sensor as the previous schemes.     

云计算中一种紧凑型的外包访问控制方案

密文策略的属性加密是实现云平台上安全的访问控制方案的最佳选择。然而,在大多数密文策略的属性加密方案中,用户密钥长度与属性的个数之间成线性关系;用户的解密时间与访问结构的复杂度成正比关系。为了减少用户密钥的存储和解密计算开销,本文提出一种面向云计算平台的紧凑型的外包访问控制方案。方案中的访问结构可以支持“与”、“或”以及“门限”三种策略。它仅采用简单的哈希和异或运算就可以验证用户外包解密返回的数据是否正确。在随机预言机模型中,基于aMSE-DDH难题,证明了方案是选择密文攻击安全的。分析表明,本文方案能够安全的实现云计算环境下的访问控制,尤其当用户终端设备受限时实现的访问控制。      

云端数据访问控制中基于中间代理的用户撤销新方法

基于属性的加密机制是云端大数据细粒度访问控制的重要方法,其中的用户撤销是访问控制的重要一环,但现有的用户撤销方法因为仅仅重新加密对称密钥或者需要重新加密原始数据,所以存在安全性差或效率低的问题。针对上述问题,提出了一种基于中间代理的用户撤销方法,来解决在细粒度访问控制环境下用户撤销所带来的安全和效率问题。该用户撤销方法主要思想是利用中间代理辅助处理原始密文,继而由用户完成转化后密文的解密。由于用户没有单独解密密文的能力,因此不需要重新加密共享数据,从而在用户撤销后保证了数据的安全性,又解决了效率问题。理论分析以及实验结果表明,所提出的方法相较现有方法能够在细粒度访问控制环境下达到安全且高效的用户撤销。     

Access control scheme with attribute revocation for SWIM

Access control scheme is proposed for System Wide Information Management (SWIM) to address the problem of attribute revocation in practical applications. Based on the attribute based encryption (ABE), this scheme introduces the proxy re-encryption mechanism and key encrypting key (KEK) tree to realize fine-grained access control with attribute revocation. This paper defines the attributes according to the status quo of civil aviation. Compared with some other schemes proposed before, this scheme not only shortens the length of ciphertext (CT) and private key but also improves the efficiency of encryption and decryption. The scheme can resist collusion attacks and ensure the security of data in SWIM.     

Attribute-based encryption scheme supporting attribute revocation in cloud storage environment

Attribute-based encryption (ABE) scheme is widely used in the cloud storage due to its fine-grained access control.Each attribute in ABE may be shared by multiple users at the same time.Therefore,how to achieve attribute-level user revocation is currently facing an important challenge.Through research,it has been found that some attribute-level user revocation schemes currently can’t resist the collusion attack between the revoked user and the existing user.To solve this problem,an attribute-based encryption scheme that supported the immediate attribute revocation was proposed.The scheme could achieve attribute-level user revocation and could effectively resist collusion attacks between the revoked users and the existing users.At the same time,this scheme outsourced complex decryption calculations to cloud service providers with powerful computing ability,which reduced the computational burden of the data user.The scheme was proved secure based on computational Diffie-Hellman assumption in the standard model.Finally,the functionality and efficiency of the proposed scheme were analyzed and verified.The experimental results show that the proposed scheme can safely implement attribute-level user revocation and has the ability to quickly decrypt,which greatly improves the system efficiency.     

一种适用于工业控制系统的加密传输方案

随着工业物联网(IoT)、云计算等信息技术与工业控制系统(ICS)的整合,工业数据的安全正面临着极大风险。为了能在这样一个复杂的分布式环境中保护数据的机密性和完整性,该文采用基于属性的加密(ABE)算法,设计一种集数据加密、访问控制、解密外包、数据验证为一体的通信方案,同时具有密文长度恒定的特点。最后,从正确性、安全性和性能开销3个方面对方案进行详细的分析,并通过仿真验证得出该算法具有低解密开销的优势。     

数据外包环境下一种支持撤销的属性基加密方案

In order to support fine-grained attribute revocation in data outsourcing systems,an attribute-based encryption scheme with efficient revocation in indirect revocation model was proposed.The model of ABE supporting attribute revocation was given,and a concrete scheme was constructed which proved its security under the standard model.Compared to the existing related schemes,the size of ciphertext and private/secret key is reduced,and the new scheme achieves fine-grained and immediate attribute revocation which is more suitable for the practical applications.     

支持属性撤销的可验证多关键词搜索加密方案

近年来,可搜索加密技术及细粒度访问控制的属性加密在云存储环境下得到广泛应用。考虑到现存的基于属性的可搜索加密方案存在仅支持单关键词搜索而不支持属性撤销的问题,以及单关键词搜索可能造成返回搜索结果部分错误并导致计算和宽带资源浪费的缺陷,该文提出一种支持属性撤销的可验证多关键词搜索加密方案。该方案允许用户检测云服务器搜索结果的正确性,同时在细粒度访问控制结构中支持用户属性的撤销,且在属性撤销过程中不需要更新密钥和重加密密文。该文在随机预言机模型下基于判定性线性假设被证明具有抵抗选择关键词集攻击安全性及关键词隐私性,同时从理论和实验两方面分析验证了该方案具有较高的计算效率与存储效率。     

可验证外包解密的离线/在线属性基加密方案

属性基加密可以为雾-云计算中的数据提供机密性保护和细粒度访问控制,但雾-云计算系统中的移动设备难以承担属性基加密的繁重计算负担。为解决该问题,该文提出一种可验证外包解密的离线/在线属性基加密方案。该方案能够实现离线/在线的密钥生成和数据加密,同时支持可验证外包解密。然后,给出方案的选择明文攻击的安全证明和可验证性的安全证明。之后,该文将转换阶段所需双线性对的计算量降为恒定常数。最后,从理论和实验两方面对所提方案进行性能分析,实验结果表明该方案是有效且实用的。     

Secure communication in CloudIoT through design of a lightweight authentication and session key agreement scheme

Internet of Things (IoT) is a newly emerged paradigm where multiple embedded devices, known as things, are connected via the Internet to collect, share, and analyze data from the environment. In order to overcome the limited storage and processing capacity constraint of IoT devices, it is now possible to integrate them with cloud servers as large resource pools. Such integration, though bringing applicability of IoT in many domains, raises concerns regarding the authentication of these devices while establishing secure communications to cloud servers. Recently, Kumari et al proposed an authentication scheme based on elliptic curve cryptography (ECC) for IoT and cloud servers and claimed that it satisfies all security requirements and is secure against various attacks. In this paper, we first prove that the scheme of Kumari et al is susceptible to various attacks, including the replay attack and stolen-verifier attack. We then propose a lightweight authentication protocol for secure communication of IoT embedded devices and cloud servers. The proposed scheme is proved to provide essential security requirements such as mutual authentication, device anonymity, and perfect forward secrecy and is robust against security attacks. We also formally verify the security of the proposed protocol using BAN logic and also the Scyther tool. We also evaluate the computation and communication costs of the proposed scheme and demonstrate that the proposed scheme incurs minimum computation and communication overhead, compared to related schemes, making it suitable for IoT environments with low processing and storage capacity.     

Ciphertext-Policy Attribute Based Encryption Supporting Any Monotone Access Structures Without Escrow

Ciphertext policy attribute-based encryp-tion (CP-ABE) is becoming a new primitive for fine-grained access control. It neither produces multiple en-crypted copies of the same data nor suffers from the severe burden of key distribution and management. The escrow problem that the central authority could decrypt any ci-phertexts addressed to all the specific users is still a chal-lenge for CP-ABE mechanism. One new CP-ABE scheme without escrow is proposed, and furthermore the proposed scheme achieves fully security in the standard model. The performance and security analysis results indicate that the proposed CP-ABE scheme is extremely appropriate for cloud storage system.