On the Connection between Signcryption and One-pass Key Establishment

Key establishment between two parties that uses only one message transmission is referred to as one-pass key establishment (OPKE). OPKE provides the opportunity for very efficient constructions, even though they will typically provide a lower level of security than the corresponding multi-pass variants. In this paper, we explore the intuitive connection between signcryption and OPKE. By establishing a formal relationship between these two primitives, we show that with appropriate security notions, OPKE can be used as a signcryption KEM and vice versa. In order to establish the connection we explore the definitions of security for signcryption (KEM) and give new and generalised definitions. By making our generic constructions concrete we are able to provide new examples of signcryption KEMs and an OPKE protocol

Identity-Concealed Authenticated Encryption and Key Exchange

Identity concealment and zero-round trip time (0-RTT) connection are two of current research focuses in the design and analysis of secure transport protocols, like TLS1.3 and Google\u27s QUIC, in the client-server setting. In this work, we introduce a new primitive for identity-concealed authenticated encryption in the public-key setting, referred to as {higncryption, which can be viewed as a novel monolithic integration of public-key encryption, digital signature, and identity concealment. We present the security definitional framework for higncryption, and a conceptually simple (yet carefully designed) protocol construction. As a new primitive, higncryption can have many applications. In this work, we focus on its applications to 0-RTT authentication, showing higncryption is well suitable to and compatible with QUIC and OPTLS, and on its applications to identity-concealed authenticated key exchange (CAKE) and unilateral CAKE (UCAKE). In particular, we make a systematic study on applying and incorporating higncryption to TLS. Of independent interest is a new concise security definitional framework for CAKE and UCAKE proposed in this work, which unifies the traditional BR and (post-ID) frameworks, enjoys composability, and ensures very strong security guarantee. Along the way, we make a systematically comparative study with related protocols and mechanisms including Zheng\u27s signcryption, one-pass HMQV, QUIC, TLS1.3 and OPTLS, most of which are widely standardized or in use

Identity-Concealed Authenticated Encryption from Ring Learning With Errors (Full version)

Authenticated encryption (AE) is very suitable for a resources constrained environment for it needs less computational costs and AE has become one of the important technologies of modern communication security. Identity concealment is one of research focuses in design and analysis of current secure transport protocols (such as TLS1.3 and Google\u27s QUIC). In this paper, we present a provably secure identity-concealed authenticated encryption in the public-key setting over ideal lattices, referred to as RLWE-ICAE. Our scheme can be regarded as a parallel extension of higncryption scheme proposed by Zhao (CCS 2016), but in the lattice-based setting. RLWE-ICAE can be viewed as a monolithic integration of public-key encryption, key agreement over ideal lattices, identity concealment and digital signature. The security of RLWE-ICAE is directly relied on the Ring Learning with Errors (RLWE) assumption. Two concrete choices of parameters are provided in the end

Revisiting the Feasibility of Public Key Cryptography in Light of IIoT Communications

Digital certificates are regarded as the most secure and scalable way of implementing authentication services in the Internet today. They are used by most popular security protocols, including Transport Layer Security (TLS) and Datagram Transport Layer Security (DTLS). The lifecycle management of digital certificates relies on centralized Certification Authority (CA)-based Public Key Infrastructures (PKIs). However, the implementation of PKIs and certificate lifecycle management procedures in Industrial Internet of Things (IIoT) environments presents some challenges, mainly due to the high resource consumption that they imply and the lack of trust in the centralized CAs. This paper identifies and describes the main challenges to implement certificate-based public key cryptography in IIoT environments and it surveys the alternative approaches proposed so far in the literature to address these challenges. Most proposals rely on the introduction of a Trusted Third Party to aid the IIoT devices in tasks that exceed their capacity. The proposed alternatives are complementary and their application depends on the specific challenge to solve, the application scenario, and the capacities of the involved IIoT devices. This paper revisits all these alternatives in light of industrial communication models, identifying their strengths and weaknesses, and providing an in-depth comparative analysis.This work was financially supported by the European commission through ECSEL-JU 2018 program under the COMP4DRONES project (grant agreement N∘ 826610), with national financing from France, Spain, Italy, Netherlands, Austria, Czech, Belgium and Latvia. It was also partially supported by the Ayudas Cervera para Centros Tecnológicos grant of the Spanish Centre for the Development of Industrial Technology (CDTI) under the project EGIDA (CER-20191012), and in part by the Department of Economic Development and Competitiveness of the Basque Government through the project TRUSTIND—Creating Trust in the Industrial Digital Transformation (KK-2020/00054)

Secure Authentication and Privacy-Preserving Techniques in Vehicular Ad-hoc NETworks (VANETs)

In the last decade, there has been growing interest in Vehicular Ad Hoc NETworks (VANETs). Today car manufacturers have already started to equip vehicles with sophisticated sensors that can provide many assistive features such as front collision avoidance, automatic lane tracking, partial autonomous driving, suggestive lane changing, and so on. Such technological advancements are enabling the adoption of VANETs not only to provide safer and more comfortable driving experience but also provide many other useful services to the driver as well as passengers of a vehicle. However, privacy, authentication and secure message dissemination are some of the main issues that need to be thoroughly addressed and solved for the widespread adoption/deployment of VANETs. Given the importance of these issues, researchers have spent a lot of effort in these areas over the last decade. We present an overview of the following issues that arise in VANETs: privacy, authentication, and secure message dissemination. Then we present a comprehensive review of various solutions proposed in the last 10 years which address these issues. Our survey sheds light on some open issues that need to be addressed in the future

Towards Enhanced Usability of IT Security Mechanisms - How to Design Usable IT Security Mechanisms Using the Example of Email Encryption

Nowadays, advanced security mechanisms exist to protect data, systems, and networks. Most of these mechanisms are effective, and security experts can handle them to achieve a sufficient level of security for any given system. However, most of these systems have not been designed with focus on good usability for the average end user. Today, the average end user often struggles with understanding and using security mecha-nisms. Other security mechanisms are simply annoying for end users. As the overall security of any system is only as strong as the weakest link in this system, bad usability of IT security mechanisms may result in operating errors, resulting in inse-cure systems. Buying decisions of end users may be affected by the usability of security mechanisms. Hence, software provid-ers may decide to better have no security mechanism then one with a bad usability. Usability of IT security mechanisms is one of the most underestimated properties of applications and sys-tems. Even IT security itself is often only an afterthought. Hence, usability of security mechanisms is often the after-thought of an afterthought. This paper presents some guide-lines that should help software developers to improve end user usability of security-related mechanisms, and analyzes com-mon applications based on these guidelines. Based on these guidelines, the usability of email encryption is analyzed and an email encryption solution with increased usability is presented. The approach is based on an automated key and trust man-agement. The compliance of the proposed email encryption solution with the presented guidelines for usable security mechanisms is evaluated

Critical Perspectives on Provable Security: Fifteen Years of Another Look Papers

We give an overview of our critiques of “proofs” of security and a guide to our papers on the subject that have appeared over the past decade and a half. We also provide numerous additional examples and a few updates and errata

Proposal and evaluation of authentication protocols for Smart Grid networks

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Elétrica, 2018.Uma rede Smart Grid (ou rede elétrica inteligente) representa a evolução das redes elétricas tradicionais, tornada possível graças à integração das tecnologias da informação e das comunicações com a infraestrutura elétrica. Esta integração propicia o surgimento de novos serviços, tornando a rede elétrica mais eficiente, gerando também novos desafios a serem atendidos, dentre eles a segurança do sistema. A rede SG deve garantir a confiabilidade, a integridade e a privacidade dos dados armazenados ou em transito pelo sistema, o que leva à necessidade de autenticação e controle de acesso, obrigando a todo usuário ou dispositivo a se autenticar e a realizar somente operações autorizadas. A autenticação de usuários e dispositivos é um processo muito importante para a rede SG, e os protocolos usados para esse fim devem ser capazes de proteção contra possiveis ataques (por exemplo, Man-in-the-Middle - MITM, repetição, Denegação de Serviço - DoS). Por outro lado, a autorização é tratada em conjunto com a autenticação e relacionada com as politicas de controle de acesso do sistema. Uma parte essencial para criar os protocolos de autenticação seguros envolve os esquemas de ciframento. O uso de um ou a combinação de vários esquemas afeta diretamente o desempenho do protocolo. Cada dia novos esquemas são propostos, e seu emprego nos protocolos de autenticação melhora o desempenho do sistema em comparação aos protocolos já propostos no mesmo cenário. Neste trabalho são propostos 3 (três) protocolos de autenticação seguros e de custo adequado para os cenários descritos a seguir: - Autenticação dos empregados das empresas de fornecimento de energia que procuram acesso ao sistema de forma remota; - Autenticação de Smart Meters numa Infraestrutura de medição avançada (AMI, do inglês Advanced Metering Infrastructure) baseada em nuvem computacional; e - Autenticação de veículos elétricos em uma rede V2G (do inglês, Vehicle-to-Grid). Cada um dos cenários tem caraterísticas particulares que são refletidas no projeto dos protocolos propostos. Além disso, todos os protocolos propostos neste trabalho garantem a autenticação mutua entre todas as entidades e a proteção da privacidade, confidencialidade e integridade dos dados do sistema. Uma comparação dos custos de comunicação e computação é apresentada entre os protocolos propostos neste trabalho e protocolos desenvolvidos por outros autores para cada um dos cenários. Os resultados das comparações mostram que os protocolos propostos neste trabalho têm, na maioria dos casos, o melhor desempenho computacional e de comunicações, sendo assim uma ótima escolha para a sua implementação nas redes SG. A validação formal dos protocolos propostos por meio da ferramenta AVISPA é realizada, permitindo verificar o atendimento a requisitos de segurança.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES).A Smart Grid network (or inteligent electrical network) represents the evolution of traditional electrical networks, made possible due to the integration of information and communication technologies with the electrical power grid. This integration generates new services and improves the efficiency of the electrical power grid, while new challenges appear and must be solved, including the security of the system. The SG network must assure reliability, integrity and privacy of the data stored or in trnsit in the system, leading to the need for authentication and access control, thus all users and devices must authenticate and accomplish only authorized operations. The authentication of users and devices is a very important process for the SG network, and the protocols used for this task must be able to protect against possible attacks (for example, Man- in-the-Middle - MITM, repetição, Denegação de Serviço – DoS). On the other hand, authorization is treated jointly with authentication and related to policies of access control to the system. An essential part of creating secure authentication protocols involves encryption schemes. The use of one or the combination of several schemes directly affects protocol performance. Each day new schemas are proposed, and their utilization in the authentication protocols improves the performance of the system compared to the protocols already proposed in the same scenario. In this work 3 (three) secure and cost-effective authentication protocols are proposed, for the following scenarios: - Authentication of employees of energy suply enterprises, looking for remote or local access to the system; - Authentication of Smart Meters in an Advanced Metering Infrastructure based on cloud computing; and - Authentication of electrical vehicles in a V2G (“Vehicle-to-Grid”) network. Each scenario has specific characteristics, that are reflected on the design of the proposed protocols. Moreover, such protocols assure mutual authentication among entities as well as the protection of privacy, confidentiality and integrity of system data. A comparison considering communication and computing costs is presented, involving proposed protocols and other previously published protocols, for each scenario. The results show that the proposed protocols have, in most cases, the best performance, thus constituting good choices for future implementation in SG networks. The formal validation of the proposed protocols by the use of AVISPA tool is realized, allowing to verify the compliance with security requirements