With the in-depth application of new technologies such as big data in education fields,the storage and sharing model of student education records data still faces many challenges in terms of privacy protection and eff...With the in-depth application of new technologies such as big data in education fields,the storage and sharing model of student education records data still faces many challenges in terms of privacy protection and efficient transmission.In this paper,we propose a data security storage and sharing scheme based on consortium blockchain,which is a credible search scheme without verification.In our scheme,the implementation of data security storage is using the blockchain and storage server together.In detail,the smart contract provides protection for data keywords,the storage server stores data after data masking,and the blockchain ensures the traceability of query transactions.The need for precise privacy data is achieved by constructing a dictionary.Cryptographic techniques such as AES and RSA are used for encrypted storage of data,keywords,and digital signatures.Security analysis and performance evaluation shows that the availability,high efficiency,and privacy-preserving can be achieved.Meanwhile,this scheme has better robustness compared to other educational records data sharing models.展开更多
Unauthorized access to location information in location-based service is one of the most critical security threats to mobile Internet.In order to solve the problem of quality of location sharing while keeping privacy ...Unauthorized access to location information in location-based service is one of the most critical security threats to mobile Internet.In order to solve the problem of quality of location sharing while keeping privacy preserved,adaptive privacy preserved location sharing scheme called APPLSS is proposed,which is based on a new hierarchical ciphertext-policy attribute-based encryption algorithm.In the algorithm,attribute authority sets the attribute vector according to the attribute tags of registration from the location service providers.Then the attribute vector can be adaptively transformed into an access structure to control the encryption and decryption.The APPLSS offers a natural hierarchical mechanism in protecting location information when partially sharing it in mobile networks.It allows service providers access to end user’s sensitive location more flexibly,and satisfies a sufficient-but-no-more strategy.For end-users,the quality of service is obtained while no extra location privacy is leaked.To improve service response performance,outsourced decryption is deployed to avoid the bottlenecks of the service providers and location information providers.The performance analysis and experiments show that APPLSS is an efficient and practical location sharing scheme.展开更多
Searchable public key encryption is a useful cryptographic paradigm that enables an untrustworthy server to retrieve the encrypted data without revealing the contents of the data. It offers a promising solution to enc...Searchable public key encryption is a useful cryptographic paradigm that enables an untrustworthy server to retrieve the encrypted data without revealing the contents of the data. It offers a promising solution to encrypted data retrieval in cryptographic cloud storage. Certificateless public key cryptography (CLPKC) is a novel cryptographic primitive that has many merits. It overcomes the key escrow problem in identity-based cryptography (IBC) and the cumbersome certificate problem in conventional public key cryptography (PKC). Motivated by the appealing features of CLPKC, several certificateless encryption with keyword search (CLEKS) schemes have been presented in the literature. But, our cryptanalysis demonstrates that the previously proposed CLEKS frameworks suffer from the security vulnerability caused by the keyword guessing attack. To remedy the security weakness in the previous frameworks and provide resistance against both inside and outside keyword guessing attacks, we propose a new CLEKS framework. Under the new framework, we design a concrete CLEKS scheme and formally prove its security in the random oracle model. Compared with previous two CLEKS schemes, the proposed scheme has better overall performance while offering stronger security guarantee as it withstands the existing known types of keyword guessing attacks.展开更多
The m ajor advantages of EBS-based key rrkanagerrent scheme are its enhanced network survivability, high dynamic performance, and better support for network expansion. But it suffers from the collusion problem, which ...The m ajor advantages of EBS-based key rrkanagerrent scheme are its enhanced network survivability, high dynamic performance, and better support for network expansion. But it suffers from the collusion problem, which means it is prone to the cooperative attack of evicted members. A novel EBS-based collusion resistant group management scheme utilizing the construction of Ciphertext-Policy Attribute-Based Encryption （CP-ABE） is proposed. The new scheme satisfies the desired security properties, such as forward secrecy, backward secrecy and collusion secrecy. Compared with existing EBS-based key rmnagement scheme, the new scheme can resolve EBS collusion problem completely. Even all evicted members work together, and share their individual piece of information, they could not access to the new group key. In addition, our scheme is more efficient in terms of conmnication and computation overhead when the group size is large. It can be well controlled even in the case of large-scale application scenarios.展开更多
云辅助医疗物联网系统是智慧医疗领域发展的新趋势,患者隐私数据通常以密态的形式外包存储于云端,这将导致数据拥有者失去对自身数据的控制权限,并带来数据检索不便.针对上述问题,本文提出了一种支持策略隐藏的可搜索属性加密方案,结合...云辅助医疗物联网系统是智慧医疗领域发展的新趋势,患者隐私数据通常以密态的形式外包存储于云端,这将导致数据拥有者失去对自身数据的控制权限,并带来数据检索不便.针对上述问题,本文提出了一种支持策略隐藏的可搜索属性加密方案,结合密文策略属性加密与公钥可搜索加密的优势,确保云辅助(cloud-assisted Internet of Medical Things,IoMT)系统中共享数据的机密性,实现了敏感数据的细粒度访问控制并支持关键字搜索.并且,利用在线/离线加密和外包解密等方法降低了资源受限设备的计算开销,使得密文策略的属性加密方案可以在云辅助IoMT系统中实施.同时,引入策略隐藏技术,将属性加密访问策略中的属性值隐藏于密文中,防止数据拥有者的隐私泄露.在安全性方面,证明本方案的密文信息在选定访问结构和选择明文攻击下具有不可区分性,以及陷门信息在选择关键字攻击下具有不可区分性.最后,利用JPBC(Javapairing-based cryptography)密码库对本方案与其他相关方案在功能特性、通信开销和计算开销等方面进行对比,结果表明本方案在密钥生成和加密阶段计算效率更高且存储开销更低.展开更多
Despite that existing data sharing systems in online social networks （OSNs） propose to encrypt data before sharing, the multiparty access control of encrypted data has become a challenging issue. In this paper, we p...Despite that existing data sharing systems in online social networks （OSNs） propose to encrypt data before sharing, the multiparty access control of encrypted data has become a challenging issue. In this paper, we propose a secure data sharing scheme in 0SNs based on ciphertext-policy attribute- based proxy re-encryption and secret sharing. In order to protect users＇ sensitive data, our scheme allows users to customize access policies of their data and then outsource encrypted data to the OSNs service provider. Our scheme presents a multiparty access control model, which enables the disseminator to update the access policy of ciphertext if their attributes satisfy the existing access policy. Further, we present a partial decryption construction in which the computation overhead of user is largely reduced by delegating most of the decryption operations to the OSNs service provider. We also provide checkability on the results returned from the OSNs service provider to guarantee the correctness of partial decrypted ciphertext. Moreover, our scheme presents an efficient attribute revocation method that achieves both forward and backward secrecy. The security and performance analysis results indicate that the proposed scheme is secure and efficient in OSNs.展开更多
基金The research work was supported by the National Key Research and Development Plan in China(Grant No.2020YFB1005500)Key Project Plan of Blockchain in Ministry of Education of the People’s Republic of China(Grant No.2020KJ010802)Natural Science Foundation of Beijing Municipality(Grant No.M21034).
文摘With the in-depth application of new technologies such as big data in education fields,the storage and sharing model of student education records data still faces many challenges in terms of privacy protection and efficient transmission.In this paper,we propose a data security storage and sharing scheme based on consortium blockchain,which is a credible search scheme without verification.In our scheme,the implementation of data security storage is using the blockchain and storage server together.In detail,the smart contract provides protection for data keywords,the storage server stores data after data masking,and the blockchain ensures the traceability of query transactions.The need for precise privacy data is achieved by constructing a dictionary.Cryptographic techniques such as AES and RSA are used for encrypted storage of data,keywords,and digital signatures.Security analysis and performance evaluation shows that the availability,high efficiency,and privacy-preserving can be achieved.Meanwhile,this scheme has better robustness compared to other educational records data sharing models.
基金supported by the National Natural Science and Foundation of China(61572521)Research and Innovation term of Engineering University of PAP(KYTD201805).
文摘Unauthorized access to location information in location-based service is one of the most critical security threats to mobile Internet.In order to solve the problem of quality of location sharing while keeping privacy preserved,adaptive privacy preserved location sharing scheme called APPLSS is proposed,which is based on a new hierarchical ciphertext-policy attribute-based encryption algorithm.In the algorithm,attribute authority sets the attribute vector according to the attribute tags of registration from the location service providers.Then the attribute vector can be adaptively transformed into an access structure to control the encryption and decryption.The APPLSS offers a natural hierarchical mechanism in protecting location information when partially sharing it in mobile networks.It allows service providers access to end user’s sensitive location more flexibly,and satisfies a sufficient-but-no-more strategy.For end-users,the quality of service is obtained while no extra location privacy is leaked.To improve service response performance,outsourced decryption is deployed to avoid the bottlenecks of the service providers and location information providers.The performance analysis and experiments show that APPLSS is an efficient and practical location sharing scheme.
基金supported by the National Natural Science Foundation of China under Grant Nos. 61772009 and U1736112the Natural Science Foundation of Jiangsu Province under Grant Nos. BK20161511 and BK20181304
文摘Searchable public key encryption is a useful cryptographic paradigm that enables an untrustworthy server to retrieve the encrypted data without revealing the contents of the data. It offers a promising solution to encrypted data retrieval in cryptographic cloud storage. Certificateless public key cryptography (CLPKC) is a novel cryptographic primitive that has many merits. It overcomes the key escrow problem in identity-based cryptography (IBC) and the cumbersome certificate problem in conventional public key cryptography (PKC). Motivated by the appealing features of CLPKC, several certificateless encryption with keyword search (CLEKS) schemes have been presented in the literature. But, our cryptanalysis demonstrates that the previously proposed CLEKS frameworks suffer from the security vulnerability caused by the keyword guessing attack. To remedy the security weakness in the previous frameworks and provide resistance against both inside and outside keyword guessing attacks, we propose a new CLEKS framework. Under the new framework, we design a concrete CLEKS scheme and formally prove its security in the random oracle model. Compared with previous two CLEKS schemes, the proposed scheme has better overall performance while offering stronger security guarantee as it withstands the existing known types of keyword guessing attacks.
基金Acknowledgements The authors would like to thank the reviewers for their detailed reviews and constructive comments, which have helped improve the quality of this paper. This work was supported by the National Natural Science Foundation of China under Crant No. 60873231, the Natural Science Foundation of Jiangsu Province under Grant No. BK2009426, Major State Basic Research Development Program of China under Cwant No.2011CB302903 and Key University Science Research Project of Jiangsu Province under Crant No. 11KJA520002.
文摘The m ajor advantages of EBS-based key rrkanagerrent scheme are its enhanced network survivability, high dynamic performance, and better support for network expansion. But it suffers from the collusion problem, which means it is prone to the cooperative attack of evicted members. A novel EBS-based collusion resistant group management scheme utilizing the construction of Ciphertext-Policy Attribute-Based Encryption （CP-ABE） is proposed. The new scheme satisfies the desired security properties, such as forward secrecy, backward secrecy and collusion secrecy. Compared with existing EBS-based key rmnagement scheme, the new scheme can resolve EBS collusion problem completely. Even all evicted members work together, and share their individual piece of information, they could not access to the new group key. In addition, our scheme is more efficient in terms of conmnication and computation overhead when the group size is large. It can be well controlled even in the case of large-scale application scenarios.
文摘云辅助医疗物联网系统是智慧医疗领域发展的新趋势,患者隐私数据通常以密态的形式外包存储于云端,这将导致数据拥有者失去对自身数据的控制权限,并带来数据检索不便.针对上述问题,本文提出了一种支持策略隐藏的可搜索属性加密方案,结合密文策略属性加密与公钥可搜索加密的优势,确保云辅助(cloud-assisted Internet of Medical Things,IoMT)系统中共享数据的机密性,实现了敏感数据的细粒度访问控制并支持关键字搜索.并且,利用在线/离线加密和外包解密等方法降低了资源受限设备的计算开销,使得密文策略的属性加密方案可以在云辅助IoMT系统中实施.同时,引入策略隐藏技术,将属性加密访问策略中的属性值隐藏于密文中,防止数据拥有者的隐私泄露.在安全性方面,证明本方案的密文信息在选定访问结构和选择明文攻击下具有不可区分性,以及陷门信息在选择关键字攻击下具有不可区分性.最后,利用JPBC(Javapairing-based cryptography)密码库对本方案与其他相关方案在功能特性、通信开销和计算开销等方面进行对比,结果表明本方案在密钥生成和加密阶段计算效率更高且存储开销更低.
基金This work has been supported by the National Natural Science Foundation of China under Grant No.61272519,the Specialized Research Fund for the Doctoral Program of Higher Education under Grant No.20120005110017,and the National Key Technology R&D Program under Grant No.2012BAH06B02
文摘Despite that existing data sharing systems in online social networks （OSNs） propose to encrypt data before sharing, the multiparty access control of encrypted data has become a challenging issue. In this paper, we propose a secure data sharing scheme in 0SNs based on ciphertext-policy attribute- based proxy re-encryption and secret sharing. In order to protect users＇ sensitive data, our scheme allows users to customize access policies of their data and then outsource encrypted data to the OSNs service provider. Our scheme presents a multiparty access control model, which enables the disseminator to update the access policy of ciphertext if their attributes satisfy the existing access policy. Further, we present a partial decryption construction in which the computation overhead of user is largely reduced by delegating most of the decryption operations to the OSNs service provider. We also provide checkability on the results returned from the OSNs service provider to guarantee the correctness of partial decrypted ciphertext. Moreover, our scheme presents an efficient attribute revocation method that achieves both forward and backward secrecy. The security and performance analysis results indicate that the proposed scheme is secure and efficient in OSNs.
