Compared to the classical cryptography, lattice-based cryptography is more secure, flexible and simple, and it is believed to be secure against quantum computers. In this paper, an efficient signature scheme is proposed from the ring learning with errors (R-LWE), which avoids sampling from discrete Gaussians and has the characteristics of the much simpler description etc. Then, the scheme is im...

We use the learning with errors (LWE) problem to build a new simple and provably secure key exchange scheme. The basic idea of the construction can be viewed as certain extension of DiffieHellman problem with errors. The mathematical structure behind comes from the commutativity of computing a bilinear form in two different ways due to the associativity of the matrix multiplications: (x ×A) × y...

Ring learning-with-errors (RLWE)-based encryption scheme is a lattice-based cryptographic algorithm that constitutes one of the most promising candidates for Post-Quantum Cryptography (PQC) standardization due to its efficient implementation and low computational complexity. xmlns:xlink="http:/...

GGH13, CLT13 and GGH15 of multilinear maps suffer from zeroizing attacks. In this paper, we present a new construction of multilinear maps using a variant of ring-LWE (vRLWE). Furthermore, we also present two new variants of vRLWE, which respectively support the applications of multipartite key exchange and witness encryption. At the same time, we also present a new variant of GGH13 using matri...

We devise a virtual black-box (VBB) obfuscator for querying whether set elements are stored within Bloom filters, with security based on the Ring Learning With Errors (RLWE) problem and strongly universal hash functions. Our construction uses an abstracted encoding scheme that we instantiate using the Gentry, Gorbunov and Halevi (GGH15) multilinear map, with an explicit security reduction to RL...

During the last years public-key encryption schemes based on the hardness of ring-LWE have gained significant popularity. For realworld security applications assuming strong adversary models, a number of practical issues still need to be addressed. In this work we thus present an instance of ring-LWE encryption that is protected against active attacks (i.e., adaptive chosen-ciphertext attacks) ...

Many lattice based cryptosystems are based on the Ring learning with errors (Ring-LWE) problem. The most critical and computationally intensive operation of these Ring-LWE based cryptosystems is polynomial multiplication over rings. In this paper, we exploit the number theoretic transform (NTT) to build a family of scalable polynomial multiplier architectures, which provide designers with a tra...

A key-homomorphic pseudorandom function (PRF) family {Fs : D → R} allows one to efficiently compute the value Fs+t(x) given Fs(x) and Ft(x). Such functions have many applications, such as distributing the operation of a key-distribution center and updatable symmetric encryption. The only known construction of key-homomorphic PRFs without random oracles, due to Boneh et al. (CRYPTO 2013), is bas...

We describe new arithmetic coding techniques and side-channel blinding countermeasures for lattice-based cryptography. Using these techniques we develop a practical, compact, and more quantum-resistant variant of the BLISS Ring-LWE Signature Scheme. We first show how the BLISS hash-based random oracle can be modified to be more secure against quantum preimage attacks while optimising signature ...