Anonymous yet traceable strong designated verifier signature

Proceedings of Information Security - 21st International Conference, ISC 2018, Guildford, UK, September 9-12, 2018info:eu-repo/semantics/publishe

One Digit Checksum for Data Integrity Verification of Cloud-executed Homomorphic Encryption Operations

Homomorphic Encryption~(HE) is used in many fields including information storage, data protection, privacy preservation, blockchain, and authentication. HE allows an untrusted third party to perform algebraic operations on encrypted data. Protecting the results of HE against accidental or malicious tampering attacks is still an open research challenge. In this paper, we introduce a lightweight technique that allows a data owner to verify the integrity of HE results performed in the cloud. The proposed method is quick, simple, and applicable, as it depends on adding a single digit to the encrypted message before storing it in the cloud. This digit represents verification proof and it is later used to ensure a verifiable HE. Our technique can be integrated with any HE scheme that uses encryption with non-isolated plaintext

Security of Ubiquitous Computing Systems

The chapters in this open access book arise out of the EU Cost Action project Cryptacus, the objective of which was to improve and adapt existent cryptanalysis methodologies and tools to the ubiquitous computing framework. The cryptanalysis implemented lies along four axes: cryptographic models, cryptanalysis of building blocks, hardware and software security engineering, and security assessment of real-world systems. The authors are top-class researchers in security and cryptography, and the contributions are of value to researchers and practitioners in these domains. This book is open access under a CC BY license

Security of Ubiquitous Computing Systems

The chapters in this open access book arise out of the EU Cost Action project Cryptacus, the objective of which was to improve and adapt existent cryptanalysis methodologies and tools to the ubiquitous computing framework. The cryptanalysis implemented lies along four axes: cryptographic models, cryptanalysis of building blocks, hardware and software security engineering, and security assessment of real-world systems. The authors are top-class researchers in security and cryptography, and the contributions are of value to researchers and practitioners in these domains. This book is open access under a CC BY license

Programming the Demirci-Selçuk Meet-in-the-Middle Attack with Constraints

International audienceCryptanalysis with SAT/SMT, MILP and CP has increased in popularity among symmetric-key cryptanalysts and designers due to its high degree of automation. So far, this approach covers differential, linear, impossible differential, zero-correlation, and integral cryptanaly-sis. However, the Demirci-Selçuk meet-in-the-middle (DS-MITM) attack is one of the most sophisticated techniques that has not been automated with this approach. By an in-depth study of Derbez and Fouque's work on DS-MITM analysis with dedicated search algorithms, we identify the crux of the problem and present a method for automatic DS-MITM attack based on general constraint programming, which allows the crypt-analysts to state the problem at a high level without having to say how it should be solved. Our method is not only able to enumerate distin-guishers but can also partly automate the key-recovery process. This approach makes the DS-MITM cryptanalysis more straightforward and easier to follow, since the resolution of the problem is delegated to off-the-shelf constraint solvers and therefore decoupled from its formulation. We apply the method to SKINNY, TWINE, and LBlock, and we get the currently known best DS-MITM attacks on these ciphers. Moreover, to demonstrate the usefulness of our tool for the block cipher designers, we exhaustively evaluate the security of 8! = 40320 versions of LBlock instantiated with different words permutations in the F functions. It turns out that the permutation used in the original LBlock is one of the 64 permutations showing the strongest resistance against the DS-MITM attack. The whole process is accomplished on a PC in less than 2 hours. The same process is applied to TWINE, and similar results are obtained

Energy Supplies in the Countries from the Visegrad Group

The purpose of this Special Issue was to collect and present research results and experiences on energy supply in the Visegrad Group countries. This research considers both macroeconomic and microeconomic aspects. It was important to determine how the V4 countries deal with energy management, how they have undergone or are undergoing energy transformation and in what direction they are heading. The articles concerned aspects of the energy balance in the V4 countries compared to the EU, including the production of renewable energy, as well as changes in its individual sectors (transport and food production). The energy efficiency of low-emission vehicles in public transport and goods deliveries are also discussed, as well as the energy efficiency of farms and energy storage facilities and the impact of the energy sector on the quality of the environment

Management: A bibliography for NASA Managers

This bibliography lists 707 reports, articles and other documents introduced into the NASA scientific and technology information system in 1985. Items are selected and grouped according to their usefulness to the manager as manager. Citations are grouped into ten subject categories: human factors and personnel issues; management theory and techniques; industrial management and manufacturing; robotics and expert systems; computers and information management; research and development; economics, costs, and markets; logistics and operations management; reliability and quality control; and legality, legislation, and policy

Privacy-preserving Attestation for Virtualized Network Infrastructures

In multi-tenant cloud environments, physical resources are shared between various parties (called tenants) through the use of virtual machines (VMs). Tenants can verify the state of their VMs by means of deep-attestation: a process by which a (physical or virtual) Trusted Platform Module --TPM -- generates attestation quotes about the integrity state of the VMs. Unfortunately, most existing deep-attestation solutions are either: limited to single-tenant environments, in which tenant {privacy is irrelevant; are inefficient in terms of {linking VM attestations to hypervisor attestations; or provide privacy and/or linking, but at the cost of modifying the TPM hardware. In this paper, we propose a privacy preserving TPM-based deep-attestation solution in multi-tenant environments, which provably guarantees: (i) Inter-tenant privacy: a tenant is unaware of whether or not the physical machine hosting its VMs also contains other VMs (belonging to other tenants); (ii) Configuration privacy: the hypervisor\u27s configuration, used in the attestation process, remains private with respect to the tenants requiring a hypervisor attestation; and (iii) Layer linking: our protocol enables tenants to link hypervisors with the VMs, thus obtaining a guarantee that their VMs are running on specific physical machines. Our solution relies on vector commitments and ZK-SNARKs. We build on the security model of Arfaoui et al. and provide both formalizations of the properties we require and proofs that our scheme does, in fact attain them. Our protocol is scalable, and our implementation results prove that it is viable, even for a large number of VMs hosted on a single platform