Blockchain-based platforms utilise cryptographic protocols to enforce the correct behaviour of users, as well guarantee a sufficient level protection against malicious adversaries. Cryptography is, however, an ever-evolving discipline, and any breakthrough would have immediate consequences on security blockchain-based applications. A possible threat currently under investigation is given by dev...

Lightweight cryptographic solutions are required to guarantee the security of Internet of Things (IoT) pervasiveness. Cryptographic primitives mandate a non-linear operation. The design of a lightweight, secure, non-linear 4 × 4 substitution box (S-box) suited to Internet of Things (IoT) applications is proposed in this work. The structure of the 4 × 4 S-box is devised in the finite fields GF (...

Hidden vector encryption (HVE), introduced by Boneh and Waters in TCC’07, is an expressive sub-class of predicate encryption, that allows conjunctive, subset, range and comparison queries over encrypted data. All existing HVE constructions in the cryptographic literature use bilinear pairings over either composite order or prime order groups. In this paper, we address the open problem of constr...

In 1992, A. Hiltgen [9] provided first constructions of provably (slightly) secure cryptographic primitives, namely feebly one-way functions. These functions are provably harder to invert than to compute, but the complexity (viewed as the circuit complexity over circuits with arbitrary binary gates) is amplified only by a constant factor (in Hiltgen’s works, the factor approaches 2). In traditi...

NIST’s Lightweight Cryptography Project ties selected crypto­ graphic algorithms to a profile, which captures the physical, performance and security characteristics of the target devices that run these algorithms. This contribution investigates the role of energy in the profile. For many of the important application domains of Lightweight Cryptography, the opera­ tion is intermittent, rather th...

While multiparty computations are becoming more and more efficient, their performance has not reached the needed level to be widely deployed for many applications. Nevertheless, the heterogeneous environment of modern computing needs this functionality to provide users their right to privacy. For a wide range of applications there is no need for complex computations, operations such as multipli...

The “Internet of Things” (IoT) promises ubiquitous, cheap, connected devices. Unfortunately, most of these devices are hastily developed and will never receive code updates. Part of the IoT’s security problem is cryptographic, but established cryptographic solutions seem too heavy or too inflexible to adapt to new use cases. Here we describe Strobe, a new lightweight framework for building both...