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
As a special kind of digital signature, verifiably encrypted signatures are used as a building block to construct optimistic fair exchange. Many verifiably encrypted signature schemes have been proposed so far and mos...As a special kind of digital signature, verifiably encrypted signatures are used as a building block to construct optimistic fair exchange. Many verifiably encrypted signature schemes have been proposed so far and most of them were proven secure under certain complexity assumptions. In this paper, however, we find that although some schemes are secure in a single-user setting, they are not secure in a multi-user setting any more. We show that Zhang, et al. ＇ s scheme, Gorantla, et al. ＇ s scheme and Ming, et al. ＇ s scheme are vulnerable to key substitution attacks, where an adversary can generate new keys satisfying legitimate verifiably encrypted signatures created by the legitimate users. We also show that this kind of attacks can breach the fairness when they are used in fair exchange in a multi-user setting.展开更多
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.
基金Supported by the National High Technology Research and Development Programme of China （ No. 2008AA092301 ） and the National Natural Science Foundation of China （No. 50879014）.
文摘As a special kind of digital signature, verifiably encrypted signatures are used as a building block to construct optimistic fair exchange. Many verifiably encrypted signature schemes have been proposed so far and most of them were proven secure under certain complexity assumptions. In this paper, however, we find that although some schemes are secure in a single-user setting, they are not secure in a multi-user setting any more. We show that Zhang, et al. ＇ s scheme, Gorantla, et al. ＇ s scheme and Ming, et al. ＇ s scheme are vulnerable to key substitution attacks, where an adversary can generate new keys satisfying legitimate verifiably encrypted signatures created by the legitimate users. We also show that this kind of attacks can breach the fairness when they are used in fair exchange in a multi-user setting.
