A new secure oblivious transfer （OT） protocol from indistinguishability obfuscation （iO） is proposed in this paper. The candidate iO and a dual-mode cryptosystem are the main technical tools of this scheme. Garg e...A new secure oblivious transfer （OT） protocol from indistinguishability obfuscation （iO） is proposed in this paper. The candidate iO and a dual-mode cryptosystem are the main technical tools of this scheme. Garg et al. introduced a candidate construction of iO in 2013. Following their steps, a new k-out-of-1 OT protocol is presented here, and its realization from decisional Diffie-Hellman （DDH） is described in this paper, in which iO was combined with the dual-mode cryptosystem. The security of the scheme mainly relies on the indistinguishability of the obf-branches （corresponding to the two modes in dual-mode model）. This paper explores a new way for the application of iO.展开更多
Fully homomorphic encryption(FHE)is a powerful cryptographic primitive that allows anyone to compute on encrypted data using only public information.So far,most FHE schemes are CPA secure.In PKC 2017,Canetti et al.ext...Fully homomorphic encryption(FHE)is a powerful cryptographic primitive that allows anyone to compute on encrypted data using only public information.So far,most FHE schemes are CPA secure.In PKC 2017,Canetti et al.extended the generic transformation of Boneh,Canetti,Halevi and Katz to turn any multi-key identity-based FHE scheme into a CCA1-secure FHE scheme.Their main construction of multi-key identity-based FHE is from probabilistic indistinguishability obfuscation(PIO)and statistical trapdoor encryption.We show that the above multi-key identity-based FHE is not secure by giving an attack.Then we give a solution to avoid the attack and redesign a more succinct and efficient multi-key identity-based FHE scheme.Compared with the scheme of Canetti et al.,ours has smaller secret key of one identity and more efficient homomorphic operations.Thus we obtain a more efficient CCA1 secure FHE scheme.展开更多
基金supported by Opening Project of State Key Laboratory of Cryptology, Scientific Research and Postgraduate Training Cooperation Project-Scientific Research Base-New Theory of Block Cipher and Obfuscation and their Application Research, and Information Management and Professional Building of Information System
文摘A new secure oblivious transfer （OT） protocol from indistinguishability obfuscation （iO） is proposed in this paper. The candidate iO and a dual-mode cryptosystem are the main technical tools of this scheme. Garg et al. introduced a candidate construction of iO in 2013. Following their steps, a new k-out-of-1 OT protocol is presented here, and its realization from decisional Diffie-Hellman （DDH） is described in this paper, in which iO was combined with the dual-mode cryptosystem. The security of the scheme mainly relies on the indistinguishability of the obf-branches （corresponding to the two modes in dual-mode model）. This paper explores a new way for the application of iO.
基金supported by National Natural Science Foundation of China[grant number 61472414,61772514,61602061]National Key R&D Program of China(2017YFB1400700).
文摘Fully homomorphic encryption(FHE)is a powerful cryptographic primitive that allows anyone to compute on encrypted data using only public information.So far,most FHE schemes are CPA secure.In PKC 2017,Canetti et al.extended the generic transformation of Boneh,Canetti,Halevi and Katz to turn any multi-key identity-based FHE scheme into a CCA1-secure FHE scheme.Their main construction of multi-key identity-based FHE is from probabilistic indistinguishability obfuscation(PIO)and statistical trapdoor encryption.We show that the above multi-key identity-based FHE is not secure by giving an attack.Then we give a solution to avoid the attack and redesign a more succinct and efficient multi-key identity-based FHE scheme.Compared with the scheme of Canetti et al.,ours has smaller secret key of one identity and more efficient homomorphic operations.Thus we obtain a more efficient CCA1 secure FHE scheme.
