Trusted Computing and Secure Virtualization in Cloud Computing

Large-scale deployment and use of cloud computing in industry is accompanied and in the same time hampered by concerns regarding protection of data handled by cloud computing providers. One of the consequences of moving data processing and storage off company premises is that organizations have less control over their infrastructure. As a result, cloud service (CS) clients must trust that the CS provider is able to protect their data and infrastructure from both external and internal attacks. Currently however, such trust can only rely on organizational processes declared by the CS provider and can not be remotely verified and validated by an external party. Enabling the CS client to verify the integrity of the host where the virtual machine instance will run, as well as to ensure that the virtual machine image has not been tampered with, are some steps towards building trust in the CS provider. Having the tools to perform such verifications prior to the launch of the VM instance allows the CS clients to decide in runtime whether certain data should be stored- or calculations should be made on the VM instance offered by the CS provider. This thesis combines three components -- trusted computing, virtualization technology and cloud computing platforms -- to address issues of trust and security in public cloud computing environments. Of the three components, virtualization technology has had the longest evolution and is a cornerstone for the realization of cloud computing. Trusted computing is a recent industry initiative that aims to implement the root of trust in a hardware component, the trusted platform module. The initiative has been formalized in a set of specifications and is currently at version 1.2. Cloud computing platforms pool virtualized computing, storage and network resources in order to serve a large number of customers customers that use a multi-tenant multiplexing model to offer on-demand self-service over broad network. Open source cloud computing platforms are, similar to trusted computing, a fairly recent technology in active development. The issue of trust in public cloud environments is addressed by examining the state of the art within cloud computing security and subsequently addressing the issues of establishing trust in the launch of a generic virtual machine in a public cloud environment. As a result, the thesis proposes a trusted launch protocol that allows CS clients to verify and ensure the integrity of the VM instance at launch time, as well as the integrity of the host where the VM instance is launched. The protocol relies on the use of Trusted Platform Module (TPM) for key generation and data protection. The TPM also plays an essential part in the integrity attestation of the VM instance host. Along with a theoretical, platform-agnostic protocol, the thesis also describes a detailed implementation design of the protocol using the OpenStack cloud computing platform. In order the verify the implementability of the proposed protocol, a prototype implementation has built using a distributed deployment of OpenStack. While the protocol covers only the trusted launch procedure using generic virtual machine images, it presents a step aimed to contribute towards the creation of a secure and trusted public cloud computing environment

Chuchotage: In-line Software Network Protocol Translation for (D)TLS

The growing diversity of connected devices leads to complex network deployments, often made up of endpoints that implement in- compatible network application protocols. Communication between heterogeneous network protocols was traditionally enabled by hardware translators or gateways. However, such solutions are increasingly unfit to address the security, scalability, and latency requirements of modern software-driven deployments. To address these shortcomings we propose Chuchotage, a protocol translation architecture for secure and scalable machine-to-machine communication. Chuchotage enables in-line TLS interception and confidential protocol translation for software-defined networks. Translation is done in ephemeral, flow-specific Trusted Execution Environments and scales with the number of network flows. Our evaluation of Chuchotage implementing an HTTP to CoAP translation indicates a minimal transmission and translation overhead, allowing its integration with legacy or outdated deployments

TREDIS – A Trusted Full-Fledged SGX-Enabled REDIS Solution

Currently, offloading storage and processing capacity to cloud servers is a growing trend among web-enabled services managing big datasets. This happens because high storage capacity and powerful processors are expensive, whilst cloud services provide cheaper, ongoing, elastic, and reliable solutions. The problem with this cloud-based out sourced solutions are that they are highly accessible through the Internet, which is good, but therefore can be considerably exposed to attacks, out of users’ control. By exploring subtle vulnerabilities present in cloud-enabled applications, management functions, op erating systems and hypervisors, an attacker may compromise the supported systems, thus compromising the privacy of sensitive user data hosted and managed in it. These attacks can be motivated by malicious purposes such as espionage, blackmail, identity theft, or harassment. A solution to this problem is processing data without exposing it to untrusted components, such as vulnerable OS components, which might be compromised by an attacker. In this thesis, we do a research on existent technologies capable of enabling appli cations to trusted environments, in order to adopt such approaches to our solution as a way to help deploy unmodified applications on top of Intel-SGX, with overheads com parable to applications designed to use this kind of technology, and also conducting an experimental evaluation to better understand how they impact our system. Thus, we present TREDIS - a Trusted Full-Fledged REDIS Key-Value Store solution, implemented as a full-fledged solution to be offered as a Trusted Cloud-enabled Platform as a Service, which includes the possibility to support a secure REDIS-cluster architecture supported by docker-virtualized services running in SGX-enabled instances, with operations run ning on always-encrypted in-memory datasets.A transição de suporte de aplicações com armazenamento e processamento em servidores cloud é uma tendência que tem vindo a aumentar, principalmente quando se precisam de gerir grandes conjuntos de dados. Comparativamente a soluções com licenciamento privado, as soluções de computação e armazenamento de dados em nuvens de serviços são capazes de oferecer opções mais baratas, de alta disponibilidade, elásticas e relativa mente confiáveis. Estas soluções fornecidas por terceiros são facilmente acessíveis através da Internet, sendo operadas em regime de outsourcing da sua operação, o que é bom, mas que por isso ficam consideravelmente expostos a ataques e fora do controle dos utiliza dores em relação às reais condições de confiabilidade, segurança e privacidade de dados. Ao explorar subtilmente vulnerabilidades presentes nas aplicações, funções de sistemas operativos (SOs), bibliotecas de virtualização de serviços de SOs ou hipervisores, um ata cante pode comprometer os sistemas e quebrar a privacidade de dados sensíveis. Estes ataques podem ser motivados por fins maliciosos como espionagem, chantagem, roubo de identidade ou assédio e podem ser desencadeados por intrusões (a partir de atacantes externos) ou por ações maliciosas ou incorretas de atacantes internos (podendo estes atuar com privilégios de administradores de sistemas). Uma solução para este problema passa por armazenar e processar a informação sem que existam exposições face a componentes não confiáveis. Nesta dissertação estudamos e avaliamos experimentalmente diversas tecnologias que permitem a execução de aplicações com isolamento em ambientes de execução confiá vel suportados em hardware Intel-SGX, de modo a perceber melhor como funcionam e como adaptá-las à nossa solução. Para isso, realizámos uma avaliação focada na utilização dessas tecnologias com virtualização em contentores isolados executando em hardware confiável, que usámos na concepção da nossa solução. Posto isto, apresentamos a nossa solução TREDIS - um sistema Key-Value Store confiável baseado em tecnologia REDIS, com garantias de integridade da execução e de privacidade de dados, concebida para ser usada como uma "Plataforma como Serviço"para gestão e armazenamento resiliente de dados na nuvem. Isto inclui a possibilidade de suportar uma arquitetura segura com garantias de resiliência semelhantes à arquitetura de replicação em cluster na solução original REDIS, mas em que os motores de execução de nós e a proteção de memória do cluster é baseado em contentores docker isolados e virtualizados em instâncias SGX, sendo os dados mantidos sempre cifrados em memória

Intel TDX Demystified: A Top-Down Approach

Intel Trust Domain Extensions (TDX) is a new architectural extension in the 4th Generation Intel Xeon Scalable Processor that supports confidential computing. TDX allows the deployment of virtual machines in the Secure-Arbitration Mode (SEAM) with encrypted CPU state and memory, integrity protection, and remote attestation. TDX aims to enforce hardware-assisted isolation for virtual machines and minimize the attack surface exposed to host platforms, which are considered to be untrustworthy or adversarial in the confidential computing's new threat model. TDX can be leveraged by regulated industries or sensitive data holders to outsource their computations and data with end-to-end protection in public cloud infrastructure. This paper aims to provide a comprehensive understanding of TDX to potential adopters, domain experts, and security researchers looking to leverage the technology for their own purposes. We adopt a top-down approach, starting with high-level security principles and moving to low-level technical details of TDX. Our analysis is based on publicly available documentation and source code, offering insights from security researchers outside of Intel

SoK: Confidential Quartet - Comparison of Platforms for Virtualization-Based Confidential Computing

Confidential computing allows processing sensitive workloads in securely isolated spaces. Following earlier adop- tion of process-based approaches to isolation, vendors are now enabling hardware and firmware support for virtualization-based confidential computing on several server platforms. Due to variations in the technology stack, threat model, implemen-tation and functionality, the available solutions offer somewhat different capabilities, trade-offs and security guarantees. In this paper we review, compare and contextualize four virtualization-based confidential computing technologies for enterprise server platforms - AMD SEV, ARM CCA, IBM PEF and Intel TDX

Defense in Depth of Resource-Constrained Devices

The emergent next generation of computing, the so-called Internet of Things (IoT), presents significant challenges to security, privacy, and trust. The devices commonly used in IoT scenarios are often resource-constrained with reduced computational strength, limited power consumption, and stringent availability requirements. Additionally, at least in the consumer arena, time-to-market is often prioritized at the expense of quality assurance and security. An initial lack of standards has compounded the problems arising from this rapid development. However, the explosive growth in the number and types of IoT devices has now created a multitude of competing standards and technology silos resulting in a highly fragmented threat model. Tens of billions of these devices have been deployed in consumers\u27 homes and industrial settings. From smart toasters and personal health monitors to industrial controls in energy delivery networks, these devices wield significant influence on our daily lives. They are privy to highly sensitive, often personal data and responsible for real-world, security-critical, physical processes. As such, these internet-connected things are highly valuable and vulnerable targets for exploitation. Current security measures, such as reactionary policies and ad hoc patching, are not adequate at this scale. This thesis presents a multi-layered, defense in depth, approach to preventing and mitigating a myriad of vulnerabilities associated with the above challenges. To secure the pre-boot environment, we demonstrate a hardware-based secure boot process for devices lacking secure memory. We introduce a novel implementation of remote attestation backed by blockchain technologies to address hardware and software integrity concerns for the long-running, unsupervised, and rarely patched systems found in industrial IoT settings. Moving into the software layer, we present a unique method of intraprocess memory isolation as a barrier to several prevalent classes of software vulnerabilities. Finally, we exhibit work on network analysis and intrusion detection for the low-power, low-latency, and low-bandwidth wireless networks common to IoT applications. By targeting these areas of the hardware-software stack, we seek to establish a trustworthy system that extends from power-on through application runtime

LightBox: Full-stack Protected Stateful Middlebox at Lightning Speed

Running off-site software middleboxes at third-party service providers has been a popular practice. However, routing large volumes of raw traffic, which may carry sensitive information, to a remote site for processing raises severe security concerns. Prior solutions often abstract away important factors pertinent to real-world deployment. In particular, they overlook the significance of metadata protection and stateful processing. Unprotected traffic metadata like low-level headers, size and count, can be exploited to learn supposedly encrypted application contents. Meanwhile, tracking the states of 100,000s of flows concurrently is often indispensable in production-level middleboxes deployed at real networks. We present LightBox, the first system that can drive off-site middleboxes at near-native speed with stateful processing and the most comprehensive protection to date. Built upon commodity trusted hardware, Intel SGX, LightBox is the product of our systematic investigation of how to overcome the inherent limitations of secure enclaves using domain knowledge and customization. First, we introduce an elegant virtual network interface that allows convenient access to fully protected packets at line rate without leaving the enclave, as if from the trusted source network. Second, we provide complete flow state management for efficient stateful processing, by tailoring a set of data structures and algorithms optimized for the highly constrained enclave space. Extensive evaluations demonstrate that LightBox, with all security benefits, can achieve 10Gbps packet I/O, and that with case studies on three stateful middleboxes, it can operate at near-native speed.Comment: Accepted at ACM CCS 201

Trusted Execution Development: Designing a Secure, High-Performance Remote Attestation Protocol

Intel Software Guard Extensions (SGX) are a Trusted Execution Environment (TEE) technology that allow programs to protect execution process and data from other processes on the platform. We propose a method to combine SGX attestation with Transport Layer Security (TLS). Doing so will combine guarantees about the program, runtime environment, and machine identity into a normal TLS handshake. We implemented a basic server using SGX/TLS and provide performance details and lessons learned during development