With the popularity of the Internet of Vehicles(IoV),a large amount of data is being generated every day.How to securely share data between the IoV operator and various value-added service providers becomes one of the...With the popularity of the Internet of Vehicles(IoV),a large amount of data is being generated every day.How to securely share data between the IoV operator and various value-added service providers becomes one of the critical issues.Due to its flexible and efficient fine-grained access control feature,Ciphertext-Policy Attribute-Based Encryption(CP-ABE)is suitable for data sharing in IoV.However,there are many flaws in most existing CP-ABE schemes,such as attribute privacy leakage and key misuse.This paper proposes a Traceable and Revocable CP-ABE-based Data Sharing with Partially hidden policy for IoV(TRE-DSP).A partially hidden access structure is adopted to hide sensitive user attribute values,and attribute categories are sent along with the ciphertext to effectively avoid privacy exposure.In addition,key tracking and malicious user revocation are introduced with broadcast encryption to prevent key misuse.Since the main computation task is outsourced to the cloud,the burden of the user side is relatively low.Analysis of security and performance demonstrates that TRE-DSP is more secure and practical for data sharing in IoV.展开更多
Conditional proxy re-encryption(CPRE)is an effective cryptographic primitive language that enhances the access control mechanism and makes the delegation of decryption permissions more granular,but most of the attribu...Conditional proxy re-encryption(CPRE)is an effective cryptographic primitive language that enhances the access control mechanism and makes the delegation of decryption permissions more granular,but most of the attribute-based conditional proxy re-encryption(AB-CPRE)schemes proposed so far do not take into account the importance of user attributes.A weighted attribute-based conditional proxy re-encryption(WAB-CPRE)scheme is thus designed to provide more precise decryption rights delegation.By introducing the concept of weight attributes,the quantity of system attributes managed by the server is reduced greatly.At the same time,a weighted tree structure is constructed to simplify the expression of access structure effectively.With conditional proxy re-encryption,large amounts of data and complex computations are outsourced to cloud servers,so the data owner(DO)can revoke the user’s decryption rights directly with minimal costs.The scheme proposed achieves security against chosen plaintext attacks(CPA).Experimental simulation results demonstrated that the decryption time is within 6–9 ms,and it has a significant reduction in communication and computation cost on the user side with better functionality compared to other related schemes,which enables users to access cloud data on devices with limited resources.展开更多
The Internet of Vehicles(IoV)has evolved as an advancement over the conventional Vehicular Ad-hoc Networks(VANETs)in pursuing a more optimal intelligent transportation system that can provide various intelligent solut...The Internet of Vehicles(IoV)has evolved as an advancement over the conventional Vehicular Ad-hoc Networks(VANETs)in pursuing a more optimal intelligent transportation system that can provide various intelligent solutions and enable a variety of applications for vehicular traffic.Massive volumes of data are produced and communicated wirelessly among the different relayed entities in these vehicular networks,which might entice adversaries and endanger the system with a wide range of security attacks.To ensure the security of such a sensitive network,we proposed a distributed authentication mechanism for IoV based on blockchain technology as a distributed ledger with an ouroboros algorithm.Using timestamp and challenge-responsemechanisms,the proposed authentication model can withstand several security attacks such asMan-in-Middle(MiM)attacks,Distributed Denial of Service(DDoS)attacks,server spoofing attacks and more.The proposed method also provides a solution for single-point failure,forward secrecy,revocability,etc.We exhibit the security of our proposed model by using formal(mathematical)analysis and informal analysis.We used Random Oracle Model to perform themathematical analysis.In addition,we compared the communication cost,computation cost,and security of the proposed model with the related existing studies.We have verified the security of the model by using AVISPA tool simulation.The security analysis and computation analysis show that the proposed protocol is viable.展开更多
In most existing CP-ABE schemes, there is only one authority in the system and all the public keys and private keys are issued by this authority, which incurs ciphertext size and computation costs in the encryption an...In most existing CP-ABE schemes, there is only one authority in the system and all the public keys and private keys are issued by this authority, which incurs ciphertext size and computation costs in the encryption and decryption operations that depend at least linearly on the number of attributes involved in the access policy. We propose an efficient multi-authority CP-ABE scheme in which the authorities need not interact to generate public information during the system initialization phase. Our scheme has constant ciphertext length and a constant number of pairing computations. Our scheme can be proven CPA-secure in random oracle model under the decision q-BDHE assumption. When user's attributes revocation occurs, the scheme transfers most re-encryption work to the cloud service provider, reducing the data owner's computational cost on the premise of security. Finally the analysis and simulation result show that the schemes proposed in this thesis ensure the privacy and secure access of sensitive data stored in the cloud server, and be able to cope with the dynamic changes of users' access privileges in large-scale systems. Besides, the multi-authority ABE eliminates the key escrow problem, achieves the length of ciphertext optimization and enhances the effi ciency of the encryption and decryption operations.展开更多
Attribute-based encryption is drawing more attention with its inherent attractive properties which are potential to be widely used in the newly developing cloud computing. However, one of the main obstacles for its ap...Attribute-based encryption is drawing more attention with its inherent attractive properties which are potential to be widely used in the newly developing cloud computing. However, one of the main obstacles for its application is how to revoke the attributes of the users, though some ABE schemes have realized revocation, they mostly focused on the user revocation that revokes the user＇s whole attributes, or attribute revocation under the indirect revocation model such that all the users＇ private keys will be affected by the revocation. In this paper, we define the model of CP-ABE supporting the attribute revocation under the direct revocation model, in which the revocation list is embed in the ciphertext and none of the users＇ private keys will be affected by the revocation process. Then we propose a generic construction, and prove its security with the decision q-BDHE assumption.展开更多
Distributed information systems require complex access control which depends upon attributes of protected data and access policies.Traditionally,to enforce the access control,a file server is used to store all data an...Distributed information systems require complex access control which depends upon attributes of protected data and access policies.Traditionally,to enforce the access control,a file server is used to store all data and act as a reference to check the user.Apparently,the drawback of this system is that the security is based on the file server and the data are stored in plaintext.Attribute-based encryption(ABE) is introduced first by Sahai and Waters and can enable an access control mechanism over encrypted data by specifying the users’ attributes. According to this mechanism,even though the file server is compromised,we can still keep the security of the data. Besides the access control,user may be deprived of the ability in some situation,for example paying TV.More previous ABE constructions are proven secure in the selective model of security that attacker must announce the target he intends to attack before seeing the public parameters.And few of previous ABE constructions realize revocation of the users’ key.This paper presents an ABE scheme that supports revocation and has full security in adaptive model.We adapt the dual system encryption technique recently introduced by Waters to ABE to realize full security.展开更多
Access control is a key mechanism to secure outsourced data in mobile clouds. Some existing solutions are proposed to enforce flexible access control on outsourced data or reduce the computations performed by mobile d...Access control is a key mechanism to secure outsourced data in mobile clouds. Some existing solutions are proposed to enforce flexible access control on outsourced data or reduce the computations performed by mobile devices. However, less attention has been paid to the efficiency of revocation when there are mobile devices needed to be revoked. In this paper, we put forward a new solution, referred to as flexible access control with outsourceable revocation(FACOR) for mobile clouds. The FACOR applies the attribute-based encryption to enable flexible access control on outsourced data, and allows mobile users to outsource the time-consuming encryption and decryption computations to proxies, with only requiring attributes authorization to be fully trusted. As an advantageous feature, FACOR provides an outsourceable revocation for mobile users to reduce the complicated attribute-based revocation operations. The security analysis shows that our FACOR scheme achieves data security against collusion attacks and unauthorized accesses from revoked users. Both theoretical and experimental results confirm that our proposed scheme greatly reliefs the mobile devices from heavy encryption and decryption computations, as well as the complicated revocation of access rights in mobile clouds.展开更多
Attribute revocation is inevitable and al- so important for Attribute-Based Encryption （ABE） in practice. However, little attention has been paid to this issue, and it retrains one of the rmin obsta-cles for the app...Attribute revocation is inevitable and al- so important for Attribute-Based Encryption （ABE） in practice. However, little attention has been paid to this issue, and it retrains one of the rmin obsta-cles for the application of ABE. Most of existing ABE schemes support attribute revocation work under indirect revocation model such that all the users＇ private keys will be affected when the revo-cation events occur. Though some ABE schemes have realized revocation under direct revocation model such that the revocation list is embedded in the ciphertext and none of the users＇ private keys will be affected by revocation, they mostly focused on the user revocation that revokes the user＇s whole attributes, or they can only be proven to be selectively secure. In this paper, we first define a model of adaptively secure ABE supporting the at- tribute revocation under direct revocation model. Then we propose a Key-Policy ABE （KP-ABE） scheme and a Ciphertext-Policy ABE （CP-ABE） scheme on composite order bilinear groups. Finally, we prove our schemes to be adaptively secure by employing the methodology of dual system eno cryption.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 propose ...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
Attribute-based encryption(ABE) supports the fine-grained sharing of encrypted data.In some common designs,attributes are managed by an attribute authority that is supposed to be fully trustworthy.This concept implies...Attribute-based encryption(ABE) supports the fine-grained sharing of encrypted data.In some common designs,attributes are managed by an attribute authority that is supposed to be fully trustworthy.This concept implies that the attribute authority can access all encrypted data,which is known as the key escrow problem.In addition,because all access privileges are defined over a single attribute universe and attributes are shared among multiple data users,the revocation of users is inefficient for the existing ABE scheme.In this paper,we propose a novel scheme that solves the key escrow problem and supports efficient user revocation.First,an access controller is introduced into the existing scheme,and then,secret keys are generated corporately by the attribute authority and access controller.Second,an efficient user revocation mechanism is achieved using a version key that supports forward and backward security.The analysis proves that our scheme is secure and efficient in user authorization and revocation.展开更多
With the advent of cloud storage, users can share their own data in the remote cloud as a group. To ensure the security of stored data and the normal operation of public auditing, once a user is revoked from the user ...With the advent of cloud storage, users can share their own data in the remote cloud as a group. To ensure the security of stored data and the normal operation of public auditing, once a user is revoked from the user group, the data files he signed should be resigned by other legal users in the group. In this paper, we propose a new re-signature scheme utilizing backup files to rebuild data which can resist the collusion between the cloud and revoked users, and we use Shamir Secret Sharing Scheme to encrypt data in the multi-managers system which can separate the authority of the group managers. Moreover, our scheme is more practical because we do not need managers to be online all the time. Performance evaluation shows that our mechanism can improve the efficiency of the process of data re-signature.展开更多
Incorporating electric vehicles into smart grid,vehicle-to-Grid(V2G) makes it feasible to charge for large-scale electric vehicles,and in turn support electric vehicles,as mobile and distributed storage units,to disch...Incorporating electric vehicles into smart grid,vehicle-to-Grid(V2G) makes it feasible to charge for large-scale electric vehicles,and in turn support electric vehicles,as mobile and distributed storage units,to discharge to smart grid.In order to provide reliable and efficient services,the operator of V2 G networks needs to monitor realtime status of every plug-in electric vehicle(PEV) and then evaluate current electricity storage capability.Anonymity,aggregation and dynamic management are three basic but crucial characteristics of which the services of V2 G networks should be.However,few of existing authentication schemes for V2 G networks could satisfy them simultaneously.In this paper,we propose a secure and efficient authentication scheme with privacy-preserving for V2 G networks.The scheme makes the charging/discharging station authenticate PEVs anonymously and manage them dynamically.Moreover,the monitoring data collected by the charging/discharging station could be sent to a local aggregator(LAG)in batch mode.In particular,time overheads during verification stage are independent with the number of involved PEVs,and there is no need to update the membership certificate and key pair before PEV logs out.展开更多
Among several post quantum primitives proposed in the past few decades, lattice-based cryptography is considered as the most promising one, due to its underlying rich combinatorial structure, and the worst-case to ave...Among several post quantum primitives proposed in the past few decades, lattice-based cryptography is considered as the most promising one, due to its underlying rich combinatorial structure, and the worst-case to average-case reductions. The first lattice-based group signature scheme with verifier-local revocation(VLR) is treated as the first quantum-resistant scheme supported member revocation, and was put forward by Langlois et al. This VLR group signature(VLR-GS) has group public key size of O(nm log N log q), and a signature size of O(tm log N log q log β). Nguyen et al. constructed a simple efficient group signature from lattice, with significant advantages in bit-size of both the group public key and the signature. Based on their work, we present a VLR-GS scheme with group public key size of O(nm log q) and signature size of O(tm log q). Our group signature has notable advantages: support of membership revocation, and short in both the public key size and the signature size.展开更多
Vehicular Ad-hoc NETworks(VANETs)enable cooperative behaviors in vehicular environments and are seen as an integral component of Intelligent Transportation Systems(ITSs).The security of VANETs is crucial for their suc...Vehicular Ad-hoc NETworks(VANETs)enable cooperative behaviors in vehicular environments and are seen as an integral component of Intelligent Transportation Systems(ITSs).The security of VANETs is crucial for their successful deployment and widespread adoption.A critical aspect of preserving the security and privacy of VANETs is the efficient revocation of the ability of misbehaving or malicious vehicles to participate in the network.This is usually achieved by revoking the validity of the digital certificates of the offending nodes and by maintaining and distributing an accurate Certificate Revocation List(CRL).The immediate revocation of misbehaving vehicles is of prime importance for the safety of other vehicles and users.In this paper,we present a decentralized revocation approach based on Shamir’s secret sharing to revoke misbehaving vehicles with very low delays.Besides enhancing VANETs’security,our proposed protocol limits the size of the revocation list to the number of the revoked vehicles.Consequently,the authentication process is more efficient,and the communication overhead is reduced.We experimentally evaluate our protocol to demonstrate that it provides a reliable solution to the scalability,efficiency and security of VANETs.展开更多
Zero trust architecture is an end-to-end approach for server resources and data security which contains identity authentication,access control,dynamic evaluation,and so on.This work focuses on authentication technolog...Zero trust architecture is an end-to-end approach for server resources and data security which contains identity authentication,access control,dynamic evaluation,and so on.This work focuses on authentication technology in the zero trust network.In this paper,a Traceable Universal Designated Verifier Signature(TUDVS) is used to construct a privacy-preserving authentication scheme for zero trust architecture.Specifically,when a client requests access to server resources,we want to protect the client's access privacy which means that the server administrator cannot disclose the client's access behavior to any third party.In addition,the security of the proposed scheme is proved and its efficiency is analyzed.Finally,TUDVS is applied to the single packet authorization scenario of the zero trust architecture to prove the practicability of the proposed scheme.展开更多
Up to now, how to construct an efficient secure group signature scheme, which needs not to reset the system when some group members' signing keys are exposed, is still a difficult problem. A construction concernin...Up to now, how to construct an efficient secure group signature scheme, which needs not to reset the system when some group members' signing keys are exposed, is still a difficult problem. A construction concerning revocation of group members is an ideal one if it satisfies forward security which makes it more attractive for not sacrificing the security of past signatures of deleted members. This paper analyses the problem and gives a construction in which the group manager can be un-trustworthy. The scheme is efficient even when the number of revoked members is large.展开更多
How to find efficient and secure member- ship revocation algorithms is one of the most important issues standing in the way of real-world applications of group signatures. In this paper, the proof of knowledge of divi...How to find efficient and secure member- ship revocation algorithms is one of the most important issues standing in the way of real-world applications of group signatures. In this paper, the proof of knowledge of divisibility is given and a novel membership revocation method in ACJT group signature scheme is proposed： the group manager issues the product E of the public keys of current members in the group, when a group member wants to sign, he should not only proves that he has a membership certificate, but also proves that the public key in his certificate divides exactly the public key product E with zero knowledge. The proposed method is efficient since the group manager only needs one division and one exponentiation when a group member is deleted, while the signing and verifying procedure are independent of the number of current group members and excluded members, as well as the original group public key and membership certificates needn＇t be changed.展开更多
In recent years,several random key pre-distribution schemes have been proposed to bootstrap keys for encryption,but the problem of key and node revocation has received relatively little attention.In this paper,based o...In recent years,several random key pre-distribution schemes have been proposed to bootstrap keys for encryption,but the problem of key and node revocation has received relatively little attention.In this paper,based on a random key pre-distribution scheme using clustering,we present a novel random key revoca-tion protocol,which is suitable for large scale networks greatly and removes compromised information efficiently.The revocation protocol can guarantee network security by using less memory consumption and communication load,and combined by centralized and distributed revoca-tion,having virtues of timeliness and veracity for revoca-tion at the same time.展开更多
基金supported by the National Natural Science Foundation of China(No.62272076)。
文摘With the popularity of the Internet of Vehicles(IoV),a large amount of data is being generated every day.How to securely share data between the IoV operator and various value-added service providers becomes one of the critical issues.Due to its flexible and efficient fine-grained access control feature,Ciphertext-Policy Attribute-Based Encryption(CP-ABE)is suitable for data sharing in IoV.However,there are many flaws in most existing CP-ABE schemes,such as attribute privacy leakage and key misuse.This paper proposes a Traceable and Revocable CP-ABE-based Data Sharing with Partially hidden policy for IoV(TRE-DSP).A partially hidden access structure is adopted to hide sensitive user attribute values,and attribute categories are sent along with the ciphertext to effectively avoid privacy exposure.In addition,key tracking and malicious user revocation are introduced with broadcast encryption to prevent key misuse.Since the main computation task is outsourced to the cloud,the burden of the user side is relatively low.Analysis of security and performance demonstrates that TRE-DSP is more secure and practical for data sharing in IoV.
基金Programs for Science and Technology Development of Henan Province,grant number 242102210152The Fundamental Research Funds for the Universities of Henan Province,grant number NSFRF240620+1 种基金Key Scientific Research Project of Henan Higher Education Institutions,grant number 24A520015Henan Key Laboratory of Network Cryptography Technology,grant number LNCT2022-A11.
文摘Conditional proxy re-encryption(CPRE)is an effective cryptographic primitive language that enhances the access control mechanism and makes the delegation of decryption permissions more granular,but most of the attribute-based conditional proxy re-encryption(AB-CPRE)schemes proposed so far do not take into account the importance of user attributes.A weighted attribute-based conditional proxy re-encryption(WAB-CPRE)scheme is thus designed to provide more precise decryption rights delegation.By introducing the concept of weight attributes,the quantity of system attributes managed by the server is reduced greatly.At the same time,a weighted tree structure is constructed to simplify the expression of access structure effectively.With conditional proxy re-encryption,large amounts of data and complex computations are outsourced to cloud servers,so the data owner(DO)can revoke the user’s decryption rights directly with minimal costs.The scheme proposed achieves security against chosen plaintext attacks(CPA).Experimental simulation results demonstrated that the decryption time is within 6–9 ms,and it has a significant reduction in communication and computation cost on the user side with better functionality compared to other related schemes,which enables users to access cloud data on devices with limited resources.
基金This work was supported by the Ministry of Science and Technology of Taiwan,R.O.C.,under Grant MOST 110-2622-E-468-002 and 110-2218-E-468-001-MBK.
文摘The Internet of Vehicles(IoV)has evolved as an advancement over the conventional Vehicular Ad-hoc Networks(VANETs)in pursuing a more optimal intelligent transportation system that can provide various intelligent solutions and enable a variety of applications for vehicular traffic.Massive volumes of data are produced and communicated wirelessly among the different relayed entities in these vehicular networks,which might entice adversaries and endanger the system with a wide range of security attacks.To ensure the security of such a sensitive network,we proposed a distributed authentication mechanism for IoV based on blockchain technology as a distributed ledger with an ouroboros algorithm.Using timestamp and challenge-responsemechanisms,the proposed authentication model can withstand several security attacks such asMan-in-Middle(MiM)attacks,Distributed Denial of Service(DDoS)attacks,server spoofing attacks and more.The proposed method also provides a solution for single-point failure,forward secrecy,revocability,etc.We exhibit the security of our proposed model by using formal(mathematical)analysis and informal analysis.We used Random Oracle Model to perform themathematical analysis.In addition,we compared the communication cost,computation cost,and security of the proposed model with the related existing studies.We have verified the security of the model by using AVISPA tool simulation.The security analysis and computation analysis show that the proposed protocol is viable.
基金supported by National Natural Science Foundation of China under Grant No.60873231Natural Science Foundation of Jiangsu Province under Grant No.BK2009426+1 种基金Major State Basic Research Development Program of China under Grant No.2011CB302903Key University Science Research Project of Jiangsu Province under Grant No.11KJA520002
文摘In most existing CP-ABE schemes, there is only one authority in the system and all the public keys and private keys are issued by this authority, which incurs ciphertext size and computation costs in the encryption and decryption operations that depend at least linearly on the number of attributes involved in the access policy. We propose an efficient multi-authority CP-ABE scheme in which the authorities need not interact to generate public information during the system initialization phase. Our scheme has constant ciphertext length and a constant number of pairing computations. Our scheme can be proven CPA-secure in random oracle model under the decision q-BDHE assumption. When user's attributes revocation occurs, the scheme transfers most re-encryption work to the cloud service provider, reducing the data owner's computational cost on the premise of security. Finally the analysis and simulation result show that the schemes proposed in this thesis ensure the privacy and secure access of sensitive data stored in the cloud server, and be able to cope with the dynamic changes of users' access privileges in large-scale systems. Besides, the multi-authority ABE eliminates the key escrow problem, achieves the length of ciphertext optimization and enhances the effi ciency of the encryption and decryption operations.
文摘Attribute-based encryption is drawing more attention with its inherent attractive properties which are potential to be widely used in the newly developing cloud computing. However, one of the main obstacles for its application is how to revoke the attributes of the users, though some ABE schemes have realized revocation, they mostly focused on the user revocation that revokes the user＇s whole attributes, or attribute revocation under the indirect revocation model such that all the users＇ private keys will be affected by the revocation. In this paper, we define the model of CP-ABE supporting the attribute revocation under the direct revocation model, in which the revocation list is embed in the ciphertext and none of the users＇ private keys will be affected by the revocation process. Then we propose a generic construction, and prove its security with the decision q-BDHE assumption.
基金the National Natural Science Foundation of China(No.60972034)
文摘Distributed information systems require complex access control which depends upon attributes of protected data and access policies.Traditionally,to enforce the access control,a file server is used to store all data and act as a reference to check the user.Apparently,the drawback of this system is that the security is based on the file server and the data are stored in plaintext.Attribute-based encryption(ABE) is introduced first by Sahai and Waters and can enable an access control mechanism over encrypted data by specifying the users’ attributes. According to this mechanism,even though the file server is compromised,we can still keep the security of the data. Besides the access control,user may be deprived of the ability in some situation,for example paying TV.More previous ABE constructions are proven secure in the selective model of security that attacker must announce the target he intends to attack before seeing the public parameters.And few of previous ABE constructions realize revocation of the users’ key.This paper presents an ABE scheme that supports revocation and has full security in adaptive model.We adapt the dual system encryption technique recently introduced by Waters to ABE to realize full security.
基金supported in part by National High-Tech Research and Development Program of China(“863” Program)under Grant No.2015AA016004National Natural Science Foundation of China under Grants No.61173154,61272451,61572380
文摘Access control is a key mechanism to secure outsourced data in mobile clouds. Some existing solutions are proposed to enforce flexible access control on outsourced data or reduce the computations performed by mobile devices. However, less attention has been paid to the efficiency of revocation when there are mobile devices needed to be revoked. In this paper, we put forward a new solution, referred to as flexible access control with outsourceable revocation(FACOR) for mobile clouds. The FACOR applies the attribute-based encryption to enable flexible access control on outsourced data, and allows mobile users to outsource the time-consuming encryption and decryption computations to proxies, with only requiring attributes authorization to be fully trusted. As an advantageous feature, FACOR provides an outsourceable revocation for mobile users to reduce the complicated attribute-based revocation operations. The security analysis shows that our FACOR scheme achieves data security against collusion attacks and unauthorized accesses from revoked users. Both theoretical and experimental results confirm that our proposed scheme greatly reliefs the mobile devices from heavy encryption and decryption computations, as well as the complicated revocation of access rights in mobile clouds.
文摘Attribute revocation is inevitable and al- so important for Attribute-Based Encryption （ABE） in practice. However, little attention has been paid to this issue, and it retrains one of the rmin obsta-cles for the application of ABE. Most of existing ABE schemes support attribute revocation work under indirect revocation model such that all the users＇ private keys will be affected when the revo-cation events occur. Though some ABE schemes have realized revocation under direct revocation model such that the revocation list is embedded in the ciphertext and none of the users＇ private keys will be affected by revocation, they mostly focused on the user revocation that revokes the user＇s whole attributes, or they can only be proven to be selectively secure. In this paper, we first define a model of adaptively secure ABE supporting the at- tribute revocation under direct revocation model. Then we propose a Key-Policy ABE （KP-ABE） scheme and a Ciphertext-Policy ABE （CP-ABE） scheme on composite order bilinear groups. Finally, we prove our schemes to be adaptively secure by employing the methodology of dual system eno cryption.
基金supported by the National Natural Science Foundation of China under Grant No.61272519the Specialized Research Fund for the Doctoral Program of Higher Education under Grant No.20120005110017the 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.
基金supported by the NSFC(61173141,U1536206,61232016, U1405254,61373133,61502242,61572258)BK20150925+3 种基金Fund of Jiangsu Engineering Center of Network Monitoring(KJR1402)Fund of MOE Internet Innovation Platform(KJRP1403)CICAEETthe PAPD fund
文摘Attribute-based encryption(ABE) supports the fine-grained sharing of encrypted data.In some common designs,attributes are managed by an attribute authority that is supposed to be fully trustworthy.This concept implies that the attribute authority can access all encrypted data,which is known as the key escrow problem.In addition,because all access privileges are defined over a single attribute universe and attributes are shared among multiple data users,the revocation of users is inefficient for the existing ABE scheme.In this paper,we propose a novel scheme that solves the key escrow problem and supports efficient user revocation.First,an access controller is introduced into the existing scheme,and then,secret keys are generated corporately by the attribute authority and access controller.Second,an efficient user revocation mechanism is achieved using a version key that supports forward and backward security.The analysis proves that our scheme is secure and efficient in user authorization and revocation.
基金Supported by the National Natural Science Foundation of China(61572390)the National Key Research and Development Program of China(2017YFB0802000)+1 种基金the National Natural Science Foundation of Ningbo City(201601HJ-B01382)the Open Foundation of Key Laboratory of Cognitive Radio and Information Processing of Ministry of Education(Guilin University of Electronic Technology)(CRKL160202)
文摘With the advent of cloud storage, users can share their own data in the remote cloud as a group. To ensure the security of stored data and the normal operation of public auditing, once a user is revoked from the user group, the data files he signed should be resigned by other legal users in the group. In this paper, we propose a new re-signature scheme utilizing backup files to rebuild data which can resist the collusion between the cloud and revoked users, and we use Shamir Secret Sharing Scheme to encrypt data in the multi-managers system which can separate the authority of the group managers. Moreover, our scheme is more practical because we do not need managers to be online all the time. Performance evaluation shows that our mechanism can improve the efficiency of the process of data re-signature.
基金the Natural Science Foundation of China(61102056,61201132)Fundamental Research Funds for the Central Universities of China(K5051301013)the 111 Project of China(B08038)
文摘Incorporating electric vehicles into smart grid,vehicle-to-Grid(V2G) makes it feasible to charge for large-scale electric vehicles,and in turn support electric vehicles,as mobile and distributed storage units,to discharge to smart grid.In order to provide reliable and efficient services,the operator of V2 G networks needs to monitor realtime status of every plug-in electric vehicle(PEV) and then evaluate current electricity storage capability.Anonymity,aggregation and dynamic management are three basic but crucial characteristics of which the services of V2 G networks should be.However,few of existing authentication schemes for V2 G networks could satisfy them simultaneously.In this paper,we propose a secure and efficient authentication scheme with privacy-preserving for V2 G networks.The scheme makes the charging/discharging station authenticate PEVs anonymously and manage them dynamically.Moreover,the monitoring data collected by the charging/discharging station could be sent to a local aggregator(LAG)in batch mode.In particular,time overheads during verification stage are independent with the number of involved PEVs,and there is no need to update the membership certificate and key pair before PEV logs out.
基金the National Natural Science Foundations of China(Nos.61472309,61672412,61572390and 61402353)the 111 Project(No.B08038)Research Program of Anhui Education Committee(Nos.KJ2016A626,KJ2016A627)
文摘Among several post quantum primitives proposed in the past few decades, lattice-based cryptography is considered as the most promising one, due to its underlying rich combinatorial structure, and the worst-case to average-case reductions. The first lattice-based group signature scheme with verifier-local revocation(VLR) is treated as the first quantum-resistant scheme supported member revocation, and was put forward by Langlois et al. This VLR group signature(VLR-GS) has group public key size of O(nm log N log q), and a signature size of O(tm log N log q log β). Nguyen et al. constructed a simple efficient group signature from lattice, with significant advantages in bit-size of both the group public key and the signature. Based on their work, we present a VLR-GS scheme with group public key size of O(nm log q) and signature size of O(tm log q). Our group signature has notable advantages: support of membership revocation, and short in both the public key size and the signature size.
文摘Vehicular Ad-hoc NETworks(VANETs)enable cooperative behaviors in vehicular environments and are seen as an integral component of Intelligent Transportation Systems(ITSs).The security of VANETs is crucial for their successful deployment and widespread adoption.A critical aspect of preserving the security and privacy of VANETs is the efficient revocation of the ability of misbehaving or malicious vehicles to participate in the network.This is usually achieved by revoking the validity of the digital certificates of the offending nodes and by maintaining and distributing an accurate Certificate Revocation List(CRL).The immediate revocation of misbehaving vehicles is of prime importance for the safety of other vehicles and users.In this paper,we present a decentralized revocation approach based on Shamir’s secret sharing to revoke misbehaving vehicles with very low delays.Besides enhancing VANETs’security,our proposed protocol limits the size of the revocation list to the number of the revoked vehicles.Consequently,the authentication process is more efficient,and the communication overhead is reduced.We experimentally evaluate our protocol to demonstrate that it provides a reliable solution to the scalability,efficiency and security of VANETs.
基金supported in part by the National Natural Science Foundation of China(No.61702067)in part by the Natural Science Foundation of Chongqing(No.cstc2020jcyj-msxmX0343).
文摘Zero trust architecture is an end-to-end approach for server resources and data security which contains identity authentication,access control,dynamic evaluation,and so on.This work focuses on authentication technology in the zero trust network.In this paper,a Traceable Universal Designated Verifier Signature(TUDVS) is used to construct a privacy-preserving authentication scheme for zero trust architecture.Specifically,when a client requests access to server resources,we want to protect the client's access privacy which means that the server administrator cannot disclose the client's access behavior to any third party.In addition,the security of the proposed scheme is proved and its efficiency is analyzed.Finally,TUDVS is applied to the single packet authorization scenario of the zero trust architecture to prove the practicability of the proposed scheme.
基金the National Natural Science Foundation of China (No.60673081)the National Grand Foundation Research 863 Program of China (No.2006 AA01Z417).
文摘Up to now, how to construct an efficient secure group signature scheme, which needs not to reset the system when some group members' signing keys are exposed, is still a difficult problem. A construction concerning revocation of group members is an ideal one if it satisfies forward security which makes it more attractive for not sacrificing the security of past signatures of deleted members. This paper analyses the problem and gives a construction in which the group manager can be un-trustworthy. The scheme is efficient even when the number of revoked members is large.
基金supported in part by the National Nature Science Foundation of China under Grant No. 60473027
文摘How to find efficient and secure member- ship revocation algorithms is one of the most important issues standing in the way of real-world applications of group signatures. In this paper, the proof of knowledge of divisibility is given and a novel membership revocation method in ACJT group signature scheme is proposed： the group manager issues the product E of the public keys of current members in the group, when a group member wants to sign, he should not only proves that he has a membership certificate, but also proves that the public key in his certificate divides exactly the public key product E with zero knowledge. The proposed method is efficient since the group manager only needs one division and one exponentiation when a group member is deleted, while the signing and verifying procedure are independent of the number of current group members and excluded members, as well as the original group public key and membership certificates needn＇t be changed.
基金supported by the Ministry of Education Doctor Foundation in China under Grant No. 20050699037
文摘In recent years,several random key pre-distribution schemes have been proposed to bootstrap keys for encryption,but the problem of key and node revocation has received relatively little attention.In this paper,based on a random key pre-distribution scheme using clustering,we present a novel random key revoca-tion protocol,which is suitable for large scale networks greatly and removes compromised information efficiently.The revocation protocol can guarantee network security by using less memory consumption and communication load,and combined by centralized and distributed revoca-tion,having virtues of timeliness and veracity for revoca-tion at the same time.
