Faster enclave transitions for IO-intensive network applications

Process-based confidential computing enclaves such as Intel SGX have been proposed for protecting the confidentiality and integrity of network applications, without the overhead of virtualization. However, these solutions introduce other types of overhead, particularly the cost transitioning in and out of an enclave context. This makes the use of enclaves impractical for running IO-intensive applications, such as network packet processing. We build on ear- lier approaches to improve the IO performance of workloads in Intel SGX enclaves and propose the HotCall-Bundler library that helps reduce the cost of individual single enclave transitions and the total number of enclave transitions in trusted applications running in Intel SGX enclaves. We describe the implementation of the HotCall-Bundler library, evaluate its performance and demonstrate its practicality using the case study of Open vSwitch, a widely used software switch implementation

SGX-Bundler: speeding up enclave transitions for IO-intensive applications

Process-based confidential computing enclaves such as Intel SGX can be used to protect the confidentiality and integrity of workloads, without the overhead of virtualisation. However, they introduce a notable performance overhead, especially when it comes to transitions in and out of the enclave context. Such overhead makes the use of enclaves impractical for running IO-intensive applications, such as network packet processing or biological sequence analysis. We build on earlier approaches to improve the IO performance of work-loads in Intel SGX enclaves and propose the SGX-Bundler library, which helps reduce the cost of both individual single enclave transitions well as of the total number of enclave transitions in trusted applications running in Intel SGX enclaves. We describe the implementation of the SGX-Bundler library, evaluate its performance and demonstrate its practicality using the case study of Open vSwitch, a widely used software switch implementation

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

Contributions to Securing Software Updates in IoT

The Internet of Things (IoT) is a large network of connected devices. In IoT, devices can communicate with each other or back-end systems to transfer data or perform assigned tasks. Communication protocols used in IoT depend on target applications but usually require low bandwidth. On the other hand, IoT devices are constrained, having limited resources, including memory, power, and computational resources. Considering these limitations in IoT environments, it is difficult to implement best security practices. Consequently, network attacks can threaten devices or the data they transfer. Thus it is crucial to react quickly to emerging vulnerabilities. These vulnerabilities should be mitigated by firmware updates or other necessary updates securely. Since IoT devices usually connect to the network wirelessly, such updates can be performed Over-The-Air (OTA). This dissertation presents contributions to enable secure OTA software updates in IoT. In order to perform secure updates, vulnerabilities must first be identified and assessed. In this dissertation, first, we present our contribution to designing a maturity model for vulnerability handling. Next, we analyze and compare common communication protocols and security practices regarding energy consumption. Finally, we describe our designed lightweight protocol for OTA updates targeting constrained IoT devices. IoT devices and back-end systems often use incompatible protocols that are unable to interoperate securely. This dissertation also includes our contribution to designing a secure protocol translator for IoT. This translation is performed inside a Trusted Execution Environment (TEE) with TLS interception. This dissertation also contains our contribution to key management and key distribution in IoT networks. In performing secure software updates, the IoT devices can be grouped since the updates target a large number of devices. Thus, prior to deploying updates, a group key needs to be established among group members. In this dissertation, we present our designed secure group key establishment scheme. Symmetric key cryptography can help to save IoT device resources at the cost of increased key management complexity. This trade-off can be improved by integrating IoT networks with cloud computing and Software Defined Networking (SDN).In this dissertation, we use SDN in cloud networks to provision symmetric keys efficiently and securely. These pieces together help software developers and maintainers identify vulnerabilities, provision secret keys, and perform lightweight secure OTA updates. Furthermore, they help devices and systems with incompatible protocols to be able to interoperate

Спосіб захисту програмно-конфігурованої мережі від атак

В магістерській дисертації розглядається спосіб захисту програмно-конфігурованих мереж, проце процес якого базується на читання потокових таблиць перемикачів, їх аналізі нейронною мереж і запис результату в блокчейн мережу. Як практична сторона реалізований програмний продукт, змодельовує трафік мережі і виконує її аналіз і блокування відповідних злочинних нод. Прогр дозволяє захистити мережу від атак на відмову шляхом встановлення блокуючих потокових прав Програмний продукт включає реалізаці. Програмна реалізація виконанна на комбінації мов, щ включає Java, Python, javascriptThe master's thesis considers a method for protecting software-configured networks, the process of which is based on reading switch flow tables, analyzing them with a neural network, and recording the result in a blockchain network. As a practical aspect, a software product is implemented that models network traffic and performs its analysis and blocking of corresponding criminal nodes. The program allows protecting the network from denial-of-service attacks by setting up blocking flow rules. The software product includes an implementation. The software implementation is done using a combination of languages, including Java, Python, and Javascript

Cybersecurity for industrial Internet of Things: architecture, models and lessons learned

Modern industrial systems now, more than ever, require secure and efficient ways of communication. The trend of making connected, smart architectures is beginning to show in various fields of the industry such as manufacturing and logistics. The number of IoT (Internet of Things) devices used in such systems is naturally increasing and industry leaders want to define business processes which are reliable, reproducible, and can be effortlessly monitored. With the rise in number of connected industrial systems, the number of used IoT devices also grows and with that some challenges arise. Cybersecurity in these types of systems is crucial for their wide adoption. Without safety in communication and threat detection and prevention techniques, it can be very difficult to use smart, connected systems in the industry setting. In this paper we describe two real-world examples of such systems while focusing on our architectural choices and lessons learned. We demonstrate our vision for implementing a connected industrial system with secure data flow and threat detection and mitigation strategies on real-world data and IoT devices. While our system is not an off-the-shelf product, our architecture design and results show advantages of using technologies such as Deep Learning for threat detection and Blockchain enhanced communication in industrial IoT systems and how these technologies can be implemented. We demonstrate empirical results of various components of our system and also the performance of our system as-a-whole

Systems Support for Trusted Execution Environments

Cloud computing has become a default choice for data processing by both large corporations and individuals due to its economy of scale and ease of system management. However, the question of trust and trustoworthy computing inside the Cloud environments has been long neglected in practice and further exacerbated by the proliferation of AI and its use for processing of sensitive user data. Attempts to implement the mechanisms for trustworthy computing in the cloud have previously remained theoretical due to lack of hardware primitives in the commodity CPUs, while a combination of Secure Boot, TPMs, and virtualization has seen only limited adoption. The situation has changed in 2016, when Intel introduced the Software Guard Extensions (SGX) and its enclaves to the x86 ISA CPUs: for the first time, it became possible to build trustworthy applications relying on a commonly available technology. However, Intel SGX posed challenges to the practitioners who discovered the limitations of this technology, from the limited support of legacy applications and integration of SGX enclaves into the existing system, to the performance bottlenecks on communication, startup, and memory utilization. In this thesis, our goal is enable trustworthy computing in the cloud by relying on the imperfect SGX promitives. To this end, we develop and evaluate solutions to issues stemming from limited systems support of Intel SGX: we investigate the mechanisms for runtime support of POSIX applications with SCONE, an efficient SGX runtime library developed with performance limitations of SGX in mind. We further develop this topic with FFQ, which is a concurrent queue for SCONE's asynchronous system call interface. ShieldBox is our study of interplay of kernel bypass and trusted execution technologies for NFV, which also tackles the problem of low-latency clocks inside enclave. The two last systems, Clemmys and T-Lease are built on a more recent SGXv2 ISA extension. In Clemmys, SGXv2 allows us to significantly reduce the startup time of SGX-enabled functions inside a Function-as-a-Service platform. Finally, in T-Lease we solve the problem of trusted time by introducing a trusted lease primitive for distributed systems. We perform evaluation of all of these systems and prove that they can be practically utilized in existing systems with minimal overhead, and can be combined with both legacy systems and other SGX-based solutions. In the course of the thesis, we enable trusted computing for individual applications, high-performance network functions, and distributed computing framework, making a <vision of trusted cloud computing a reality

Trust and integrity in distributed systems

In the last decades, we have witnessed an exploding growth of the Internet. The massive adoption of distributed systems on the Internet allows users to offload their computing intensive work to remote servers, e.g. cloud. In this context, distributed systems are pervasively used in a number of difference scenarios, such as web-based services that receive and process data, cloud nodes where company data and processes are executed, and softwarised networks that process packets. In these systems, all the computing entities need to trust each other and co-operate in order to work properly. While the communication channels can be well protected by protocols like TLS or IPsec, the problem lies in the expected behaviour of the remote computing platforms, because they are not under the direct control of end users and do not offer any guarantee that they will behave as agreed. For example, the remote party may use non-legitimate services for its own convenience (e.g. illegally storing received data and routed packets), or the remote system may misbehave due to an attack (e.g. changing deployed services). This is especially important because most of these computing entities need to expose interfaces towards the Internet, which makes them easier to be attacked. Hence, software-based security solutions alone are insufficient to deal with the current scenario of distributed systems. They must be coupled with stronger means such as hardware-assisted protection. In order to allow the nodes in distributed system to trust each other, their integrity must be presented and assessed to predict their behaviour. The remote attestation technique of trusted computing was proposed to specifically deal with the integrity issue of remote entities, e.g. whether the platform is compromised with bootkit attacks or cracked kernel and services. This technique relies on a hardware chip called Trusted Platform Module (TPM), which is available in most business class laptops, desktops and servers. The TPM plays as the hardware root of trust, which provides a special set of capabilities that allows a physical platform to present its integrity state. With a TPM equipped in the motherboard, the remote attestation is the procedure that a physical node provides hardware-based proof of the software components loaded in this platform, which can be evaluated by other entities to conclude its integrity state. Thanks to the hardware TPM, the remote attestation procedure is resistant to software attacks. However, even though the availability of this chip is high, its actual usage is low. The major reason is that trusted computing has very little flexibility, since its goal is to provide strong integrity guarantees. For instance, remote attestation result is positive if and only if the software components loaded in the platform are expected and loaded in a specific order, which limits its applicability in real-world scenarios. For such reasons, this technique is especially hard to be applied on software services running in application layer, that are loaded in random order and constantly updated. Because of this, current remote attestation techniques provide incomplete solution. They only focus on the boot phase of physical platforms but not on the services, not to mention the services running in virtual instances. This work first proposes a new remote attestation framework with the capability of presenting and evaluating the integrity state not only of the boot phase of physical platforms but also of software services at load time, e.g. whether the software is legitimate or not. The framework allows users to know and understand the integrity state of the whole life cycle of the services they are interacting with, thus the users can make informed decision whether to send their data or trust the received results. Second, based on the remote attestation framework this thesis proposes a method to bind the identity of secure channel endpoint to a specific physical platform and its integrity state. Secure channels are extensively adopted in distributed systems to protect data transmitted from one platform to another. However, they do not convey any information about the integrity state of the platform or the service that generates and receives this data, which leaves ample space for various attacks. With the binding of the secure channel endpoint and the hardware TPM, users are protected from relay attacks (with hardware-based identity) and malicious or cracked platform and software (with remote attestation). Third, with the help of the remote attestation framework, this thesis introduces a new method to include the integrity state of software services running in virtual containers in the evidence generated by the hardware TPM. This solution is especially important for softwarised network environments. Softwarised network was proposed to provide dynamic and flexible network deployment which is an ever complex task nowadays. Its main idea is to switch hardware appliances to softwarised network functions running inside virtual instances, that are full-fledged computational systems and accessible from the Internet, thus their integrity is at stake. Unfortunately, currently remote attestation work is not able to provide hardware-based integrity evidence for software services running inside virtual instances, because the direct link between the internal of virtual instances and hardware root of trust is missing. With the solution proposed in this thesis, the integrity state of the softwarised network functions running in virtual containers can be presented and evaluated with hardware-based evidence, implying the integrity of the whole softwarised network. The proposed remote attestation framework, trusted channel and trusted softwarised network are implemented in separate working prototypes. Their performance was evaluated and proved to be excellent, allowing them to be applied in real-world scenarios. Moreover, the implementation also exposes various APIs to simplify future integration with different management platforms, such as OpenStack and OpenMANO

Mecanismos dinâmicos de segurança para redes softwarizadas e virtualizadas

The relationship between attackers and defenders has traditionally been asymmetric, with attackers having time as an upper hand to devise an exploit that compromises the defender. The push towards the Cloudification of the world makes matters more challenging, as it lowers the cost of an attack, with a de facto standardization on a set of protocols. The discovery of a vulnerability now has a broader impact on various verticals (business use cases), while previously, some were in a segregated protocol stack requiring independent vulnerability research. Furthermore, defining a perimeter within a cloudified system is non-trivial, whereas before, the dedicated equipment already created a perimeter. This proposal takes the newer technologies of network softwarization and virtualization, both Cloud-enablers, to create new dynamic security mechanisms that address this asymmetric relationship using novel Moving Target Defense (MTD) approaches. The effective use of the exploration space, combined with the reconfiguration capabilities of frameworks like Network Function Virtualization (NFV) and Management and Orchestration (MANO), should allow for adjusting defense levels dynamically to achieve the required security as defined by the currently acceptable risk. The optimization tasks and integration tasks of this thesis explore these concepts. Furthermore, the proposed novel mechanisms were evaluated in real-world use cases, such as 5G networks or other Network Slicing enabled infrastructures.A relação entre atacantes e defensores tem sido tradicionalmente assimétrica, com os atacantes a terem o tempo como vantagem para conceberem uma exploração que comprometa o defensor. O impulso para a Cloudificação do mundo torna a situação mais desafiante, pois reduz o custo de um ataque, com uma padronização de facto sobre um conjunto de protocolos. A descoberta de uma vulnerabilidade tem agora um impacto mais amplo em várias verticais (casos de uso empresarial), enquanto anteriormente, alguns estavam numa pilha de protocolos segregados que exigiam uma investigação independente das suas vulnerabilidades. Além disso, a definição de um perímetro dentro de um sistema Cloud não é trivial, enquanto antes, o equipamento dedicado já criava um perímetro. Esta proposta toma as mais recentes tecnologias de softwarização e virtualização da rede, ambas facilitadoras da Cloud, para criar novos mecanismos dinâmicos de segurança que incidem sobre esta relação assimétrica utilizando novas abordagens de Moving Target Defense (MTD). A utilização eficaz do espaço de exploração, combinada com as capacidades de reconfiguração de frameworks como Network Function Virtualization (NFV) e Management and Orchestration (MANO), deverá permitir ajustar dinamicamente os níveis de defesa para alcançar a segurança necessária, tal como definida pelo risco actualmente aceitável. As tarefas de optimização e de integração desta tese exploram estes conceitos. Além disso, os novos mecanismos propostos foram avaliados em casos de utilização no mundo real, tais como redes 5G ou outras infraestruturas de Network Slicing.Programa Doutoral em Engenharia Informátic

Cyber-Storms Come from Clouds: Security of Cloud Computing in the IoT Era

The Internet of Things (IoT) is rapidly changing our society to a world where every "thing" is connected to the Internet, making computing pervasive like never before. This tsunami of connectivity and data collection relies more and more on the Cloud, where data analytics and intelligence actually reside. Cloud computing has indeed revolutionized the way computational resources and services can be used and accessed, implementing the concept of utility computing whose advantages are undeniable for every business. However, despite the benefits in terms of flexibility, economic savings, and support of new services, its widespread adoption is hindered by the security issues arising with its usage. From a security perspective, the technological revolution introduced by IoT and Cloud computing can represent a disaster, as each object might become inherently remotely hackable and, as a consequence, controllable by malicious actors. While the literature mostly focuses on security of IoT and Cloud computing as separate entities, in this article we provide an up-to-date and well-structured survey of the security issues of Cloud computing in the IoT era. We give a clear picture of where security issues occur and what their potential impact is. As a result, we claim that it is not enough to secure IoT devices, as cyber-storms come from Clouds