Public key encryption scheme with keyword search （PEKS） enables us to search the encrypted data in a cloud server with a keyword, and no one can obtain any infor- mation about the encrypted data without the trapdoor...Public key encryption scheme with keyword search （PEKS） enables us to search the encrypted data in a cloud server with a keyword, and no one can obtain any infor- mation about the encrypted data without the trapdoor corresponding to the keyword. The PEKS is useful to keep the management of large data storages secure such as those in a cloud. In this paper, to protect against quantum computer attacks, we present a lattice-based identity-based encryption scheme with key- word search. We have proved that our scheme can achieve ciphertext indistinguishability in the random oracle model, and our scheme can also achieve trapdoor security. In particular, our scheme can designate a unique tester to test and return the search results, therefore it does not need a secure channel. To the best of our knowledge, our scheme is the first iden- tity-based encryption scheme with keyword search from lattice assumption.展开更多
Because of the concise functionality of oblivious transfer （OT） protocols, they have been widely used as building blocks in secure multiparty computation and high-level protocols. The security of OT protocols built ...Because of the concise functionality of oblivious transfer （OT） protocols, they have been widely used as building blocks in secure multiparty computation and high-level protocols. The security of OT protocols built upon classical number theoretic problems, such as the discrete logarithm and factoring, however, is threatened as a result of the huge progress in quantum computing. Therefore, post-quantum cryptography is needed for protocols based on classical problems, and several proposals for post-quantum OT protocols exist. However, most post-quantum cryptosystems present their security proof only in the context of classical adversaries, not in the quantum setting. In this paper, we close this gap and prove the security of the lattice-based OT protocol proposed by Peikert et al. （CRYPTO, 2008）, which is universally composably secure under the assumption of learning with errors hardness, in the quantum setting. We apply three general quantum security analysis frameworks. First, we apply the quantum lifting theorem proposed by Unruh （EUROCRYPT, 2010） to prove that the security of the lattice-based OT protocol can be lifted into the quantum world. Then, we apply two more security analysis frameworks specified for post-quantum cryptographic primitives, i.e., simple hybrid arguments （CRYPTO, 2011） and game-preserving reduction （PQCrypto, 2014）.展开更多
基金supported by the National Natural Science Foundation of China (No.61370203)China Postdoctoral Science Foundation Funded Project (No.2017M623008)+1 种基金Scientific Research Starting Project of SWPU (No.2017QHZ023)State Scholarship Foundation of China Scholarship Council (No.201708515149)
文摘Public key encryption scheme with keyword search （PEKS） enables us to search the encrypted data in a cloud server with a keyword, and no one can obtain any infor- mation about the encrypted data without the trapdoor corresponding to the keyword. The PEKS is useful to keep the management of large data storages secure such as those in a cloud. In this paper, to protect against quantum computer attacks, we present a lattice-based identity-based encryption scheme with key- word search. We have proved that our scheme can achieve ciphertext indistinguishability in the random oracle model, and our scheme can also achieve trapdoor security. In particular, our scheme can designate a unique tester to test and return the search results, therefore it does not need a secure channel. To the best of our knowledge, our scheme is the first iden- tity-based encryption scheme with keyword search from lattice assumption.
基金Project supported by the National Key R&D Program of China(No.2017YFB0802000)the National Natural Science Foundation of China(Nos.61672412,61472309,and 61572390)the China Scholarship Council(No.201406960041)
文摘Because of the concise functionality of oblivious transfer （OT） protocols, they have been widely used as building blocks in secure multiparty computation and high-level protocols. The security of OT protocols built upon classical number theoretic problems, such as the discrete logarithm and factoring, however, is threatened as a result of the huge progress in quantum computing. Therefore, post-quantum cryptography is needed for protocols based on classical problems, and several proposals for post-quantum OT protocols exist. However, most post-quantum cryptosystems present their security proof only in the context of classical adversaries, not in the quantum setting. In this paper, we close this gap and prove the security of the lattice-based OT protocol proposed by Peikert et al. （CRYPTO, 2008）, which is universally composably secure under the assumption of learning with errors hardness, in the quantum setting. We apply three general quantum security analysis frameworks. First, we apply the quantum lifting theorem proposed by Unruh （EUROCRYPT, 2010） to prove that the security of the lattice-based OT protocol can be lifted into the quantum world. Then, we apply two more security analysis frameworks specified for post-quantum cryptographic primitives, i.e., simple hybrid arguments （CRYPTO, 2011） and game-preserving reduction （PQCrypto, 2014）.
