A Trusted and Privacy-Enhanced In-Memory Data Store

The recent advent of hardware-based trusted execution environments provides isolated execution, protected from untrusted operating systems, allowing for the establishment of hardware-shielded trust computing base components. As the processor provides such a “shielded” trusted execution environment (TEE), their use will allow users to run appli cations securely, for example on the remote cloud servers, whose operating systems and hardware are exposed to potentially malicious remote attackers, non-controlled system administrators and staff from the cloud providers. On the other hand, Linux containers managed by Docker or Kubernetes are interesting solutions to provide lower resource footprints, faster and flexible startup times, and higher I/O performance, compared with virtual machines (VM) enabled by hypervisors. However, these solutions suffer from soft ware kernel mechanisms, easier to be compromised in confidentiality and integrity as sumptions of supported application data. In this dissertation we designed, implemented and evaluated a Trusted and Privacy-Enhanced In-Memory Data Store, making use of a hardware-shielded containerised OS-library to support its trust-ability assumptions. To support large datasets, requiring data to be mapped outside those hardware-enabled con tainers, our solution uses partial homomorphic encryption, allowing trusted operations executed in the protected execution environment to manage in-memory always-encrypted data, that can be or not mapped inside the TEE.Os recentes avanços de ambientes de execução confiáveis baseados em hardware fornecem execução isolada, protegida contra sistemas operativos não confiáveis, permitindo o estabelecimento de componentes base de computação de confiança protegidos por hardware. Como o processador fornece esses ambientes de execução confiável e "protegida" (TEE), o seu uso permitirá que os utilizadores executem aplicações com segurança, por exemplo em servidores cloud remotos, cujos sistemas operativos e hardware estão expostos a atacantes potencialmente maliciosos assim como administradores de sistema não controlados e membros empregados dos sistemas de cloud. Por outro lado, os containers Linux geridos por sistemas Docker ou Kubernetes são soluções interessantes para poupar recursos físicos, obter tempos de inicialização mais rápidos e flexíveis e maior desempenho de I/O (interfaces de entrada e saída), em comparação com as tradicionais máquinas virtuais (VM) activadas pelos hipervisores. No entanto, essas soluções sofrem com software e mecanismos de kernel mais fáceis de comprometerem os dados das aplicações na sua integridade e privacidade. Nesta dissertação projectamos, implementamos e avaliamos um Sistema de Armazenamento de Dados em Memória Confiável e Focado na Privacidade, utilizando uma biblioteca conteinerizada e protegida por hardware para suportar as suas suposições de capacidade de confiança. Para oferecer suporte para grandes conjuntos de dados, exigindo assim que os dados sejam mapeados fora dos containers seguros pelo hardware, a solução utiliza encriptação homomórfica parcial, permitindo que operações executadas no ambiente de execução protegido façam gestão de dados na memória que estão permanentemente cifrados, estando eles mapeados dentro ou fora dos containers seguros

A tale of two worlds:assessing the vulnerability of enclave shielding runtimes

status: publishe

Trustworthy Wireless Personal Area Networks

In the Internet of Things (IoT), everyday objects are equipped with the ability to compute and communicate. These smart things have invaded the lives of everyday people, being constantly carried or worn on our bodies, and entering into our homes, our healthcare, and beyond. This has given rise to wireless networks of smart, connected, always-on, personal things that are constantly around us, and have unfettered access to our most personal data as well as all of the other devices that we own and encounter throughout our day. It should, therefore, come as no surprise that our personal devices and data are frequent targets of ever-present threats. Securing these devices and networks, however, is challenging. In this dissertation, we outline three critical problems in the context of Wireless Personal Area Networks (WPANs) and present our solutions to these problems. First, I present our Trusted I/O solution (BASTION-SGX) for protecting sensitive user data transferred between wirelessly connected (Bluetooth) devices. This work shows how in-transit data can be protected from privileged threats, such as a compromised OS, on commodity systems. I present insights into the Bluetooth architecture, Intel’s Software Guard Extensions (SGX), and how a Trusted I/O solution can be engineered on commodity devices equipped with SGX. Second, I present our work on AMULET and how we successfully built a wearable health hub that can run multiple health applications, provide strong security properties, and operate on a single charge for weeks or even months at a time. I present the design and evaluation of our highly efficient event-driven programming model, the design of our low-power operating system, and developer tools for profiling ultra-low-power applications at compile time. Third, I present a new approach (VIA) that helps devices at the center of WPANs (e.g., smartphones) to verify the authenticity of interactions with other devices. This work builds on past work in anomaly detection techniques and shows how these techniques can be applied to Bluetooth network traffic. Specifically, we show how to create normality models based on fine- and course-grained insights from network traffic, which can be used to verify the authenticity of future interactions

A TrustZone-assisted secure silicon on a co-design framework

Dissertação de mestrado em Engenharia Eletrónica Industrial e ComputadoresEmbedded systems were for a long time, single-purpose and closed systems, characterized by hardware resource constraints and real-time requirements. Nowadays, their functionality is ever-growing, coupled with an increasing complexity and heterogeneity. Embedded applications increasingly demand employment of general-purpose operating systems (GPOSs) to handle operator interfaces and general-purpose computing tasks, while simultaneously ensuring the strict timing requirements. Virtualization, which enables multiple operating systems (OSs) to run on top of the same hardware platform, is gaining momentum in the embedded systems arena, driven by the growing interest in consolidating and isolating multiple and heterogeneous environments. The penalties incurred by classic virtualization approaches is pushing research towards hardware-assisted solutions. Among the existing commercial off-the-shelf (COTS) technologies for virtualization, ARM TrustZone technology is gaining momentum due to the supremacy and lower cost of TrustZone-enabled processors. Programmable system-on-chips (SoCs) are becoming leading players in the embedded systems space, because the combination of a plethora of hard resources with programmable logic enables the efficient implementation of systems that perfectly fit the heterogeneous nature of embedded applications. Moreover, novel disruptive approaches make use of field-programmable gate array (FPGA) technology to enhance virtualization mechanisms. This master’s thesis proposes a hardware-software co-design framework for easing the economy of addressing the new generation of embedded systems requirements. ARM TrustZone is exploited to implement the root-of-trust of a virtualization-based architecture that allows the execution of a GPOS side-by-side with a real-time OS (RTOS). RTOS services were offloaded to hardware, so that it could present simultaneous improvements on performance and determinism. Instead of focusing in a concrete application, the goal is to provide a complete framework, specifically tailored for Zynq-base devices, that developers can use to accelerate a bunch of distinct applications across different embedded industries.Os sistemas embebidos foram, durante muitos anos, sistemas com um simples e único propósito, caracterizados por recursos de hardware limitados e com cariz de tempo real. Hoje em dia, o número de funcionalidades começa a escalar, assim como o grau de complexidade e heterogeneidade. As aplicações embebidas exigem cada vez mais o uso de sistemas operativos (OSs) de uso geral (GPOS) para lidar com interfaces gráficas e tarefas de computação de propósito geral. Porém, os seus requisitos primordiais de tempo real mantém-se. A virtualização permite que vários sistemas operativos sejam executados na mesma plataforma de hardware. Impulsionada pelo crescente interesse em consolidar e isolar ambientes múltiplos e heterogéneos, a virtualização tem ganho uma crescente relevância no domínio dos sistemas embebidos. As adversidades que advém das abordagens de virtualização clássicas estão a direcionar estudos no âmbito de soluções assistidas por hardware. Entre as tecnologias comerciais existentes, a tecnologia ARM TrustZone está a ganhar muita relevância devido à supremacia e ao menor custo dos processadores que suportam esta tecnologia. Plataformas hibridas, que combinam processadores com lógica programável, estão em crescente penetração no domínio dos sistemas embebidos pois, disponibilizam um enorme conjunto de recursos que se adequam perfeitamente à natureza heterogénea dos sistemas atuais. Além disso, existem soluções recentes que fazem uso da tecnologia de FPGA para melhorar os mecanismos de virtualização. Esta dissertação propõe uma framework baseada em hardware-software de modo a cumprir os requisitos da nova geração de sistemas embebidos. A tecnologia TrustZone é explorada para implementar uma arquitetura que permite a execução de um GPOS lado-a-lado com um sistemas operativo de tempo real (RTOS). Os serviços disponibilizados pelo RTOS são migrados para hardware, para melhorar o desempenho e determinismo do OS. Em vez de focar numa aplicação concreta, o objetivo é fornecer uma framework especificamente adaptada para dispositivos baseados em System-on-chips Zynq, de forma a que developers possam usar para acelerar um vasto número de aplicações distintas em diferentes setores

Ordered Merkle Tree a Versatile Data-Structure for Security Kernels

Hidden undesired functionality is an unavoidable reality in any complex hardware or software component. Undesired functionality — deliberately introduced Trojan horses or accidentally introduced bugs — in any component of a system can be exploited by attackers to exert control over the system. This poses a serious security risk to systems — especially in the ever growing number of systems based on networks of computers. The approach adopted in this dissertation to secure systems seeks immunity from hidden functionality. Specifcally, if a minimal trusted computing base (TCB) for any system can be identifed, and if we can eliminate hidden functionality in the TCB, all desired assurances regarding the operation of the system can be guaranteed. More specifcally, the desired assurances are guaranteed even if undesired functionality may exist in every component of the system outside the TCB. A broad goal of this dissertation is to characterize the TCB for various systems as a set of functions executed by a trusted security kernel. Some constraints are deliberately imposed on the security kernel functionality to reduce the risk of hidden functionality inside the security kernel. In the security model adopted in this dissertation, any system is seen as an interconnection of subsystems, where each subsystem is associated with a security kernel. The security kernel for a subsystem performs only the bare minimal tasks required to assure the integrity of the tasks performed by the subsystem. Even while the security kernel functionality may be different for each system/subsystem, it is essential to identify reusable components of the functionality that are suitable for a wide range of systems. The contribution of the research is a versatile data-structure — Ordered Merkle Tree (OMT), which can act as the reusable component of various security kernels. The utility of OMT is illustrated by designing security kernels for subsystems participating in, 1) a remote fle storage system, 2) a generic content distribution system, 3) generic look-up servers, 4) mobile ad-hoc networks and 5) the Internet’s routing infrastructure based on the border gateway protocol (BGP)

An Implementation of Multitask Scheduling Algorithm for VXWworks

The application of real time multitasking on a single processor increases day by day and its implementation complexity also increases. The real time systems have raised many scheduling issues, Such as Hierarchical scheduling and resource sharing. While hypothesis turns out to be more developed, but the implementation of real time multitasking systems still to be a challenge for designers. In embedded real-time operating systems (RTOS), As the number of tasks increases the complexity of Scheduling also increases, it will lead missing of task deadline. To overcome this type of problems we have designed and simulated Round-robin scheduling (RR), Rate Monotonic scheduling (RMS), and Earliest Deadline First scheduling (EDF) algorithms by using single Portable Operating System Interface (POSIX) timer in Wind River Vxworks 6.9.The communication among the tasks could be established by using semaphores. The purpose of the implementation of these scheduling algorithms is: We would like to verify the various task scheduling schemes and develop a novel task scheduling scheme if required for proposed Vxworks based DAC system. During implementation of Multitask Scheduler, we have also implemented some basic scheduling algorithms. We present details of the implementation of Round-robin scheduling (RR), Rate Monotonic scheduling (RMS), and Earliest Deadline First scheduling (EDF) algorithms

Using Context and Interactions to Verify User-Intended Network Requests

Client-side malware can attack users by tampering with applications or user interfaces to generate requests that users did not intend. We propose Verified Intention (VInt), which ensures a network request, as received by a service, is user-intended. VInt is based on "seeing what the user sees" (context). VInt screenshots the user interface as the user interacts with a security-sensitive form. There are two main components. First, VInt ensures output integrity and authenticity by validating the context, ensuring the user sees correctly rendered information. Second, VInt extracts user-intended inputs from the on-screen user-provided inputs, with the assumption that a human user checks what they entered. Using the user-intended inputs, VInt deems a request to be user-intended if the request is generated properly from the user-intended inputs while the user is shown the correct information. VInt is implemented using image analysis and Optical Character Recognition (OCR). Our evaluation shows that VInt is accurate and efficient

Evaluation of Windows Servers Security Under ICMP and TCP Denial of Service Attacks

Securing server from Distributed denial of service (DDoS) attacks is a challenging task for network operators. DDOS attacks are known to reduce the performance of web based applications and reduce the number of legitimate client connections. In this thesis, we evaluate performance of a Windows server 2003 under these attacks. In this thesis, we also evaluate and compare effectiveness of three different protection mechanisms, namely SYN Cache, SYN Cookie and SYN proxy protection methods, to protect against TCP SYN DDoS attacks. It is found that the SYN attack protection at the server is more effective at lower loads of SYN attack traffic, whereas the SYN cookies protection is more effective at higher loads compared to other methods