Chameleon: A Secure Cloud-Enabled and Queryable System with Elastic Properties

There are two dominant themes that have become increasingly more important in our technological society. First, the recurrent use of cloud-based solutions which provide infrastructures, computation platforms and storage as services. Secondly, the use of applicational large logs for analytics and operational monitoring in critical systems. Moreover, auditing activities, debugging of applications and inspection of events generated by errors or potential unexpected operations - including those generated as alerts by intrusion detection systems - are common situations where extensive logs must be analyzed, and easy access is required. More often than not, a part of the generated logs can be deemed as sensitive, requiring a privacy-enhancing and queryable solution. In this dissertation, our main goal is to propose a novel approach of storing encrypted critical data in an elastic and scalable cloud-based storage, focusing on handling JSONbased ciphered documents. To this end, we make use of Searchable and Homomorphic Encryption methods to allow operations on the ciphered documents. Additionally, our solution allows for the user to be near oblivious to our system’s internals, providing transparency while in use. The achieved end goal is a unified middleware system capable of providing improved system usability, privacy, and rich querying over the data. This previously mentioned objective is addressed while maintaining server-side auditable logs, allowing for searchable capabilities by the log owner or authorized users, with integrity and authenticity proofs. Our proposed solution, named Chameleon, provides rich querying facilities on ciphered data - including conjunctive keyword, ordering correlation and boolean queries - while supporting field searching and nested aggregations. The aforementioned operations allow our solution to provide data analytics upon ciphered JSON documents, using Elasticsearch as our storage and search engine.O uso recorrente de soluções baseadas em nuvem tornaram-se cada vez mais importantes na nossa sociedade. Tais soluções fornecem infraestruturas, computação e armazenamento como serviços, para alem do uso de logs volumosos de sistemas e aplicações para análise e monitoramento operacional em sistemas críticos. Atividades de auditoria, debugging de aplicações ou inspeção de eventos gerados por erros ou possíveis operações inesperadas - incluindo alertas por sistemas de detecção de intrusão - são situações comuns onde logs extensos devem ser analisados com facilidade. Frequentemente, parte dos logs gerados podem ser considerados confidenciais, exigindo uma solução que permite manter a confidencialidades dos dados durante procuras. Nesta dissertação, o principal objetivo é propor uma nova abordagem de armazenar logs críticos num armazenamento elástico e escalável baseado na cloud. A solução proposta suporta documentos JSON encriptados, fazendo uso de Searchable Encryption e métodos de criptografia homomórfica com provas de integridade e autenticação. O objetivo alcançado é um sistema de middleware unificado capaz de fornecer privacidade, integridade e autenticidade, mantendo registos auditáveis do lado do servidor e permitindo pesquisas pelo proprietário dos logs ou usuários autorizados. A solução proposta, Chameleon, visa fornecer recursos de consulta atuando em cima de dados cifrados - incluindo queries conjuntivas, de ordenação e booleanas - suportando pesquisas de campo e agregações aninhadas. As operações suportadas permitem à nossa solução suportar data analytics sobre documentos JSON cifrados, utilizando o Elasticsearch como armazenamento e motor de busca

Practical Isolated Searchable Encryption in a Trusted Computing Environment

Cloud computing has become a standard computational paradigm due its numerous advantages, including high availability, elasticity, and ubiquity. Both individual users and companies are adopting more of its services, but not without loss of privacy and control. Outsourcing data and computations to a remote server implies trusting its owners, a problem many end-users are aware. Recent news have proven data stored on Cloud servers is susceptible to leaks from the provider, third-party attackers, or even from government surveillance programs, exposing users’ private data. Different approaches to tackle these problems have surfaced throughout the years. Naïve solutions involve storing data encrypted on the server, decrypting it only on the client-side. Yet, this imposes a high overhead on the client, rendering such schemes impractical. Searchable Symmetric Encryption (SSE) has emerged as a novel research topic in recent years, allowing efficient querying and updating over encrypted datastores in Cloud servers, while retaining privacy guarantees. Still, despite relevant recent advances, existing SSE schemes still make a critical trade-off between efficiency, security, and query expressiveness, thus limiting their adoption as a viable technology, particularly in large-scale scenarios. New technologies providing Isolated Execution Environments (IEEs) may help improve SSE literature. These technologies allow applications to be run remotely with privacy guarantees, in isolation from other, possibly privileged, processes inside the CPU, such as the operating system kernel. Prominent example technologies are Intel SGX and ARM TrustZone, which are being made available in today’s commodity CPUs. In this thesis we study these new trusted hardware technologies in depth, while exploring their application to the problem of searching over encrypted data, primarily focusing in SGX. In more detail, we study the application of IEEs in SSE schemes, improving their efficiency, security, and query expressiveness. We design, implement, and evaluate three new SSE schemes for different query types, namely Boolean queries over text, similarity queries over image datastores, and multimodal queries over text and images. These schemes can support queries combining different media formats simultaneously, envisaging applications such as privacy-enhanced medical diagnosis and management of electronic-healthcare records, or confidential photograph catalogues, running without the danger of privacy breaks in Cloud-based provisioned services

Service-oriented models for audiovisual content storage

What are the important topics to understand if involved with storage services to hold digital audiovisual content? This report takes a look at how content is created and moves into and out of storage; the storage service value networks and architectures found now and expected in the future; what sort of data transfer is expected to and from an audiovisual archive; what transfer protocols to use; and a summary of security and interface issues

Cyber Security of Critical Infrastructures

Critical infrastructures are vital assets for public safety, economic welfare, and the national security of countries. The vulnerabilities of critical infrastructures have increased with the widespread use of information technologies. As Critical National Infrastructures are becoming more vulnerable to cyber-attacks, their protection becomes a significant issue for organizations as well as nations. The risks to continued operations, from failing to upgrade aging infrastructure or not meeting mandated regulatory regimes, are considered highly significant, given the demonstrable impact of such circumstances. Due to the rapid increase of sophisticated cyber threats targeting critical infrastructures with significant destructive effects, the cybersecurity of critical infrastructures has become an agenda item for academics, practitioners, and policy makers. A holistic view which covers technical, policy, human, and behavioural aspects is essential to handle cyber security of critical infrastructures effectively. Moreover, the ability to attribute crimes to criminals is a vital element of avoiding impunity in cyberspace. In this book, both research and practical aspects of cyber security considerations in critical infrastructures are presented. Aligned with the interdisciplinary nature of cyber security, authors from academia, government, and industry have contributed 13 chapters. The issues that are discussed and analysed include cybersecurity training, maturity assessment frameworks, malware analysis techniques, ransomware attacks, security solutions for industrial control systems, and privacy preservation methods

Enabling Data Security and Privacy for Database Services in the Cloud

Substantial advances in cloud technologies have made outsourcing data to the cloud highly beneficial today (e.g., costs savings, scalability, provisioning time). However, strong concerns from private companies and public institutions about the security of the outsourced data still hamper the adoption of cloud solutions. This reluctance is fed by frequent massive data breaches either caused by external attacks against cloud service providers or by negligent or opaque practices from the service provider itself. For broader adoption of cloud services, this dissertation addresses the data security and privacy concerns in the cloud setting. The goal is to ensure security and privacy of outsourced data while maintaining the ability to execute queries efficiently. Security/privacy comes at a cost of functionality/performance. Therefore, we seek for a proper balance in the space of security, privacy, functionality, and performance. This dissertation works the problems of range query execution over encrypted data, privacy preserving data mining in the context of environmental sustainability studies, and access privacy in the cloud. To enable efficient and secure range query processing over traditional databases, we introduce PINED-RQ, a highly efficient and differentially private range query execution framework that constructs a novel differentially private index over an outsourced database. Second, this dissertation presents a comprehensive study of the environmental sustainability metrics. Our contributions in this context are twofold: 1) to better evaluate the environmental impacts of the industrial processes privately, we formally define privacy preserving certification paradigm and develop a framework that enables untrusted third party to certify parties based on a well agreed upon set of criteria. 2) to explore the privacy concerns over publicizing the industrial activities in the form of life cycle assessment (LCA) computations, which is a standard way of evaluating an impact of a product and service. This dissertation initiates a study to explore privacy and security challenges that prevent organizations from making public disclosures about their activities. Finally, this dissertation explores access privacy in the cloud setting. We design and develop TaoStore, a highly efficient and practical cloud data store, which secures data confidentiality and hides access patterns from adversaries. Additionally, we propose a new ORAM security model, called aaob-security, which considers completely asynchronous network communication and concurrent processing of requests. This dissertation shows that it is possible to deliver practical and high-performance data services in the cloud without sacrificing securityand privacy if the requirements of each application are analyzed correctly and a correct balance is found in the space of security, privacy, functionality, and performance

A critical literature review of security and privacy in smart home healthcare schemes adopting IoT & blockchain: problems, challenges and solutions

Protecting private data in smart homes, a popular Internet-of-Things (IoT) application, remains a significant data security and privacy challenge due to the large-scale development and distributed nature of IoT networks. Recently, smart healthcare has leveraged smart home systems, thereby compounding security concerns in terms of the confidentiality of sensitive and private data and by extension the privacy of the data owner. However, PoA-based Blockchain DLT has emerged as a promising solution for protecting private data from indiscriminate use and thereby preserving the privacy of individuals residing in IoT-enabled smart homes. This review elicits some concerns, issues, and problems that have hindered the adoption of blockchain and IoT (BCoT) in some domains and suggests requisite solutions using the aging-in-place scenario. Implementation issues with BCoT were examined as well as the combined challenges BCoT can pose when utilised for security gains. The study discusses recent findings, opportunities, and barriers, and provide recommendations that could facilitate the continuous growth of blockchain application in healthcare. Lastly, the study then explored the potential of using a PoA-based permission blockchain with an applicable consent-based privacy model for decision-making in the information disclosure process, including the use of publisher-subscriber contracts for fine-grained access control to ensure secure data processing and sharing, as well as ethical trust in personal information disclosure, as a solution direction. The proposed authorisation framework could guarantee data ownership, conditional access management, scalable and tamper-proof data storage, and a more resilient system against threat models such as interception and insider attacks

Pseudonymization and its Application to Cloud-based eHealth Systems

Responding to the security and privacy issues of information systems, we propose a novel pseudonym solution. This pseudonym solution has provable security to protect the identities of users by employing user-generated pseudonyms. It also provides an encryption scheme to protect the security of the users’ data stored in the public network. Moreover, the pseudonym solution also provides the authentication of pseudonyms without disclosing the users’ identity information. Thus the dependences on powerful trusted third parties and on the trustworthiness of system administrators may be appreciably alleviated. Electronic healthcare systems (eHealth systems), as one kind of everyday information system, with the ability to store and share patients’ health data efficiently, have to manage in-formation of an extremely personal nature. As a consequence of known cases of abuse and attacks, the security of the health data and the privacy of patients are a great concern for many people and thus becoming obstacles to the acceptance and spread of eHealth systems. In this thesis, we survey current eHealth systems in both research and practice, analyzing potential threats to the security and privacy. Cloud-based eHealth systems, in particular, enable applications with many new features in data storing and sharing. We analyze the new issues on security and privacy when cloud technology is introduced into eHealth systems. We demonstrate that our proposed pseudonym solution can be successfully applied to cloud-based eHealth systems. Firstly, we utilize the pseudonym scheme and encryption scheme for storing and retrieving the electronic health records (EHR) in the cloud. The identities of patients and the confidentiality of EHR contents are provably guaranteed by advanced cryptographic algorithms. Secondly, we utilize the pseudonym solution to protect the privacy of patients from the health insurance companies. Only necessary information about patients is disclosed to the health insurance companies, without interrupting the cur-rent normal business processes of health insurance. At last, based on the pseudonym solution, we propose a new procedure for the secondary use of the health data. The new procedure protects the privacy of patients properly and enables patients’ full control and clear consent over their health data to be secondarily used. A prototypical application of a cloud-based eHealth system implementing our proposed solution is presented in order to exhibit the practicability of the solution and to provide intuitive experiences. Some performance estimations of the proposed solution based on the implementation are also provided.Um gewisse Sicherheits- und Datenschutzdefizite heutiger Informationssysteme zu beheben, stellen wir eine neuartige Pseudonymisierungslösung vor, die benutzergenerierte Pseudonyme verwendet und die Identitäten der Pseudonyminhaber nachweisbar wirksam schützt. Sie beinhaltet neben der Pseudonymisierung auch ein Verschlüsselungsverfahren für den Schutz der Vertraulichkeit der Benutzerdaten, wenn diese öffentlich gespeichert werden. Weiterhin bietet sie ein Verfahren zur Authentisierung von Pseudonymen, das ohne die Offenbarung von Benutzeridentitäten auskommt. Dadurch können Abhängigkeiten von vertrauenswürdigen dritten Stellen (trusted third parties) oder von vertrauenswürdigen Systemadministratoren deutlich verringert werden. Elektronische Gesundheitssysteme (eHealth-Systeme) sind darauf ausgelegt, Patientendaten effizient zu speichern und bereitzustellen. Solche Daten haben ein extrem hohes Schutzbedürfnis, und bekannte Fälle von Angriffen auf die Vertraulichkeit der Daten durch Privilegienmissbrauch und externe Attacken haben dazu geführt, dass die Sorge um den Schutz von Gesundheitsdaten und Patientenidentitäten zu einem großen Hindernis für die Verbreitung und Akzeptanz von eHealth-Systemen geworden ist. In dieser Dissertation betrachten wir gegenwärtige eHealth-Systeme in Forschung und Praxis hinsichtlich möglicher Bedrohungen für Sicherheit und Vertraulichkeit der gespeicherten Daten. Besondere Beachtung finden cloudbasierte eHealth-Systeme, die Anwendungen mit neuartigen Konzepten zur Datenspeicherung und -bereitstellung ermöglichen. Wir analysieren Sicherheits- und Vertraulichkeitsproblematiken, die sich beim Einsatz von Cloud-Technologie in eHealth-Systemen ergeben. Wir zeigen, dass unsere Pseudonymisierungslösung erfolgreich auf cloudbasierte eHealth-Systeme angewendet werden kann. Dabei werden zunächst das Pseudonymisierungs- und das Verschlüsselungsverfahren bei der Speicherung und beim Abruf von elektronischen Gesundheitsdatensätzen (electronic health records, EHR) in der Cloud eingesetzt. Die Vertraulichkeit von Patientenidentitäten und EHR-Inhalten werden dabei durch den Einsatz moderner kryptografischer Algorithmen nachweisbar garantiert. Weiterhin setzen wir die Pseudonymisierungslösung zum Schutz der Privatsphäre der Patienten gegenüber Krankenversicherungsunternehmen ein. Letzteren werden lediglich genau diejenigen Patienteninformationen offenbart, die für den störungsfreien Ablauf ihrer Geschäftsprozesse nötig sind. Schließen schlagen wir eine neuartige Vorgehensweise für die Zweitverwertung der im eHealth-System gespeicherten Daten vor, die die Pseudonymisierungslösung verwendet. Diese Vorgehensweise bietet den Patienten angemessenen Schutz für ihre Privatsphäre und volle Kontrolle darüber, welche Daten für eine Zweitverwertung (z.B. für Forschungszwecke) freigegeben werden. Es wird ein prototypisches, cloudbasiertes eHealth-System vorgestellt, das die Pseudonymisierungslösung implementiert, um deren Praktikabilität zu demonstrieren und intuitive Erfahrungen zu vermitteln. Weiterhin werden, basierend auf der Implementierung, einige Abschätzungen der Performanz der Pseudonymisierungslösung angegeben

RISC-Vコンピュータシステムに基づくシリコンレベルの信頼ルートを有する信頼できる実行環境

電気通信大学202