Public Key Encryption with Keyword Search(PEKS),an indispensable part of searchable encryption,is stock-intrade for both protecting data and providing operability of encrypted data.So far most of PEKS schemes have bee...Public Key Encryption with Keyword Search(PEKS),an indispensable part of searchable encryption,is stock-intrade for both protecting data and providing operability of encrypted data.So far most of PEKS schemes have been established on Identity-Based Cryptography(IBC) with key escrow problem inherently.Such problem severely restricts the promotion of IBC-based Public Key Infrastructure including PEKS component.Hence,Certificateless Public Key Cryptography(CLPKC) is efficient to remove such problem.CLPKC is introduced into PEKS,and a general model of Certificate/ess PEKS(CLPEKS) is formalized.In addition,a practical CLPEKS scheme is constructed with security and efficiency analyses.The proposal is secure channel free,and semantically secure against adaptive chosen keyword attack and keyword guessing attack.To illustrate the superiority,massive experiments are conducted on Enron Email dataset which is famous in information retrieval field.Compared with existed constructions,CLPEKS improves the efficiency in theory and removes the key escrow problem.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
Cloud Computing expands its usability to various fields that utilize data and store it in a common space that is required for computing and the purpose of analysis as like the IoT devices.These devices utilize the clo...Cloud Computing expands its usability to various fields that utilize data and store it in a common space that is required for computing and the purpose of analysis as like the IoT devices.These devices utilize the cloud for storing and retrieving data since the devices are not capable of storing processing data on its own.Cloud Computing provides various services to the users like the IaaS,PaaS and SaaS.The major drawback that is faced by cloud computing include the Utilization of Cloud services for the storage of data that could be accessed by all the users related to cloud.The use of Public Key Encryptions with keyword search(PEKS)provides security against the untrustworthy third-party search capability on publicly encryption keys without revealing the data’s contents.But the Security concerns of PEKs arise when Inside Keywords Guessing attacks(IKGA),is identified in the system due to the untrusted server presume the keyword in trapdoor.This issue could be solved by using various algorithms like the Certificateless Hashed Public Key Authenticated Encryption with Keyword Search(CL-HPAEKS)which utilizes the Modified Elliptic Curve Cryptography(MECC)along with the Mutation Centred flower pollinations algorithm(CM-FPA)that is used in enhancing the performance of the algorithm using the Optimization in keys.The additional use of Message Digests 5(MD5)hash function in the system enhances the security Level that is associated with the system.The system that is proposed achieves the security level performance of 96 percent and the effort consumed by the algorithm is less compared to the other encryption techniques.展开更多
Provable security has been widely used for analyzing the security of cryptosystems. Its main idea is to reduce the security to some well-defined computational assumption. The reduction process is called the security p...Provable security has been widely used for analyzing the security of cryptosystems. Its main idea is to reduce the security to some well-defined computational assumption. The reduction process is called the security proof. In this paper, we find a flaw in the security proof of BDOP-PEKS and PEKS-STAT, present a new conclusion for the security of BDOP-PEKS, and give a security proof. The flaw in the security proof of PEKS-STAT can be fixed in the same way. Finally we conclude some steps of security proof, and emphasize that the probability is as important as the construction.展开更多
The notion of searchable encrypted keywords introduced an elegant approach to retrieve encrypted data without the need of decryption. Since the introduction of this notion, there are two main searchable encrypted keyw...The notion of searchable encrypted keywords introduced an elegant approach to retrieve encrypted data without the need of decryption. Since the introduction of this notion, there are two main searchable encrypted keywords techniques, symmetric searchable encryption （SSE） and public key encryption with keyword search （PEKS）. Due to the complicated key management problem in SSE, a number of concrete PEKS constructions have been proposed to overcome it. However, the security of these PEKS schemes was only weakly defined in presence of outsider attacks;therefore they suffer from keyword guessing attacks from the database server as an insider. How to resist insider attacks remains a challenging problem. We propose the first searchable encrypted keywords against insider attacks （SEK-IA） framework to address this problem. The security model of SEK-IA under public key environment is rebuilt. We give a concrete SEK-IA construction featured with a constant-size trapdoor and the proposed scheme is formally proved to be secure against insider attacks. The performance evaluations show that the communication cost between the receiver and the server in our SEK-IA scheme remains constant, independent of the sender identity set size, and the receiver needs the minimized computational cost to generate a trapdoor to search the data from multiple senders.展开更多
Cloud computing facilitates convenient and on-demand network access to a centralized pool of resources.Currently,many users prefer to outsource data to the cloud in order to mitigate the burden of local storage.Howeve...Cloud computing facilitates convenient and on-demand network access to a centralized pool of resources.Currently,many users prefer to outsource data to the cloud in order to mitigate the burden of local storage.However,storing sensitive data on remote servers poses privacy challenges and is currently a source of concern.SE(Searchable Encryption)is a positive way to protect users sensitive data,while preserving search ability on the server side.SE allows the server to search encrypted data without leaking information in plaintext data.The two main branches of SE are SSE(Searchable Symmetric Encryption)and PEKS(Public key Encryption with Keyword Search).SSE allows only private key holders to produce ciphertexts and to create trapdoors for search,whereas PEKS enables a number of users who know the public key to produce ciphertexts but allows only the private key holder to create trapdoors.This article surveys the two main techniques of SE:SSE and PEKS.Different SE schemes are categorized and compared in terms of functionality,efficiency,and security.Moreover,we point out some valuable directions for future work on SE schemes.展开更多
基金This research was supported by the National Science Foundation of China for Funding Projects （61173089,61472298） and National Statistical Science Program of China（2013LZ46）.
文摘Public Key Encryption with Keyword Search(PEKS),an indispensable part of searchable encryption,is stock-intrade for both protecting data and providing operability of encrypted data.So far most of PEKS schemes have been established on Identity-Based Cryptography(IBC) with key escrow problem inherently.Such problem severely restricts the promotion of IBC-based Public Key Infrastructure including PEKS component.Hence,Certificateless Public Key Cryptography(CLPKC) is efficient to remove such problem.CLPKC is introduced into PEKS,and a general model of Certificate/ess PEKS(CLPEKS) is formalized.In addition,a practical CLPEKS scheme is constructed with security and efficiency analyses.The proposal is secure channel free,and semantically secure against adaptive chosen keyword attack and keyword guessing attack.To illustrate the superiority,massive experiments are conducted on Enron Email dataset which is famous in information retrieval field.Compared with existed constructions,CLPEKS improves the efficiency in theory and removes the key escrow problem.
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.
文摘Cloud Computing expands its usability to various fields that utilize data and store it in a common space that is required for computing and the purpose of analysis as like the IoT devices.These devices utilize the cloud for storing and retrieving data since the devices are not capable of storing processing data on its own.Cloud Computing provides various services to the users like the IaaS,PaaS and SaaS.The major drawback that is faced by cloud computing include the Utilization of Cloud services for the storage of data that could be accessed by all the users related to cloud.The use of Public Key Encryptions with keyword search(PEKS)provides security against the untrustworthy third-party search capability on publicly encryption keys without revealing the data’s contents.But the Security concerns of PEKs arise when Inside Keywords Guessing attacks(IKGA),is identified in the system due to the untrusted server presume the keyword in trapdoor.This issue could be solved by using various algorithms like the Certificateless Hashed Public Key Authenticated Encryption with Keyword Search(CL-HPAEKS)which utilizes the Modified Elliptic Curve Cryptography(MECC)along with the Mutation Centred flower pollinations algorithm(CM-FPA)that is used in enhancing the performance of the algorithm using the Optimization in keys.The additional use of Message Digests 5(MD5)hash function in the system enhances the security Level that is associated with the system.The system that is proposed achieves the security level performance of 96 percent and the effort consumed by the algorithm is less compared to the other encryption techniques.
基金Supported by the National Natural Science Foundation of China (60473021)
文摘Provable security has been widely used for analyzing the security of cryptosystems. Its main idea is to reduce the security to some well-defined computational assumption. The reduction process is called the security proof. In this paper, we find a flaw in the security proof of BDOP-PEKS and PEKS-STAT, present a new conclusion for the security of BDOP-PEKS, and give a security proof. The flaw in the security proof of PEKS-STAT can be fixed in the same way. Finally we conclude some steps of security proof, and emphasize that the probability is as important as the construction.
基金This work is supported by the National Natural Science Foundation of China under Grant Nos. 61300181 and 61502044, and the Fundamental Research Funds for the Central Universities of China under Grant No. 2015RC23.
文摘The notion of searchable encrypted keywords introduced an elegant approach to retrieve encrypted data without the need of decryption. Since the introduction of this notion, there are two main searchable encrypted keywords techniques, symmetric searchable encryption （SSE） and public key encryption with keyword search （PEKS）. Due to the complicated key management problem in SSE, a number of concrete PEKS constructions have been proposed to overcome it. However, the security of these PEKS schemes was only weakly defined in presence of outsider attacks;therefore they suffer from keyword guessing attacks from the database server as an insider. How to resist insider attacks remains a challenging problem. We propose the first searchable encrypted keywords against insider attacks （SEK-IA） framework to address this problem. The security model of SEK-IA under public key environment is rebuilt. We give a concrete SEK-IA construction featured with a constant-size trapdoor and the proposed scheme is formally proved to be secure against insider attacks. The performance evaluations show that the communication cost between the receiver and the server in our SEK-IA scheme remains constant, independent of the sender identity set size, and the receiver needs the minimized computational cost to generate a trapdoor to search the data from multiple senders.
基金The National Natural Science Foundation of China(No.61372103)the Natural Science Foundation of Jiangsu Province(No.BK20201265)the National Engineering Research Center of Classified Protection and Safeguard Technology for Cyber security(No.C21640-2).
基金This work is supported by Guangxi Cooperative Innovation Center of Cloud Computing and Big Data(No.YD16506)。
文摘Cloud computing facilitates convenient and on-demand network access to a centralized pool of resources.Currently,many users prefer to outsource data to the cloud in order to mitigate the burden of local storage.However,storing sensitive data on remote servers poses privacy challenges and is currently a source of concern.SE(Searchable Encryption)is a positive way to protect users sensitive data,while preserving search ability on the server side.SE allows the server to search encrypted data without leaking information in plaintext data.The two main branches of SE are SSE(Searchable Symmetric Encryption)and PEKS(Public key Encryption with Keyword Search).SSE allows only private key holders to produce ciphertexts and to create trapdoors for search,whereas PEKS enables a number of users who know the public key to produce ciphertexts but allows only the private key holder to create trapdoors.This article surveys the two main techniques of SE:SSE and PEKS.Different SE schemes are categorized and compared in terms of functionality,efficiency,and security.Moreover,we point out some valuable directions for future work on SE schemes.
