Biblio
According to the information security requirements of the industrial control system and the technical features of the existing defense measures, a dynamic security control strategy based on trusted computing is proposed. According to the strategy, the Industrial Cyber-Physical System system information security solution is proposed, and the linkage verification mechanism between the internal fire control wall of the industrial control system, the intrusion detection system and the trusted connection server is provided. The information exchange of multiple network security devices is realized, which improves the comprehensive defense capability of the industrial control system, and because the trusted platform module is based on the hardware encryption, storage, and control protection mode, It overcomes the common problem that the traditional repairing and stitching technique based on pure software leads to easy breakage, and achieves the goal of significantly improving the safety of the industrial control system . At the end of the paper, the system analyzes the implementation of the proposed secure industrial control information security system based on the trustworthy calculation.
Cyber-physical systems (CPS) and their Internet of Things (IoT) components are repeatedly subject to various attacks targeting weaknesses in their firmware. For that reason emerges an imminent demand for secure update mechanisms that not only include specific systems but cover all parts of the critical infrastructure. In this paper we introduce a theoretical concept for a secure CPS device update and verification mechanism and provide information on handling hardware-based security incorporating trusted platform modules (TPM) on those CPS devices. We will describe secure communication channels by state of the art technology and also integrity measurement mechanisms to ensure the system is in a known state. In addition, a multi-level fail-over concept is presented, ensuring continuous patching to minimize the necessity of restarting those systems.
Software agents represent an assured computing paradigm that tends to emerge to be an elegant technology to solve present day problems. The eminent Scientific Community has proved us with the usage or implementation of software agent's usage approach that simplifies the proposed solution in various types to solve the traditional computing problems arise. The proof of the same is implemented in several applications that exist based on this area of technology where the software agents have maximum benefits but on the same hand absence of the suitable security mechanisms that endures for systems that are based on representation of barriers exists in the paradigm with respect to present day industry. As the application proposing present security mechanisms is not a trivial one as the agent based system builders or developers who are not often security experts as they subsequently do not count on the area of expertise. This paper presents a novel approach for protecting the infrastructure for solving the issues considered to be malicious host in mobile agent system by implementing a secure protocol to migrate agents from host to host relying in various elements based on the enhanced Trusted Platforms Modules (TPM) for processing data. We use enhanced extension to the Java Agent Development framework (JADE) in our proposed system and a migrating protocol is used to validate the proposed framework (AVASPA).
Cyber physical systems are the key innovation driver for many domains such as automotive, avionics, industrial process control, and factory automation. However, their interconnection potentially provides adversaries easy access to sensitive data, code, and configurations. If attackers gain control, material damage or even harm to people must be expected. To counteract data theft, system manipulation and cyber-attacks, security mechanisms must be embedded in the cyber physical system. Adding hardware security in the form of the standardized Trusted Platform Module (TPM) is a promising approach. At the same time, traditional dependability features such as safety, availability, and reliability have to be maintained. To determine the right balance between security and dependability it is essential to understand their interferences. This paper supports developers in identifying the implications of using TPMs on the dependability of their system.We highlight potential consequences of adding TPMs to cyber-physical systems by considering the resulting safety, reliability, and availability. Furthermore, we discuss the potential of enhancing the dependability of TPM services by applying traditional redundancy techniques.
Trustworthy operation of industrial control systems depends on secure and real-time code execution on the embedded programmable logic controllers (PLCs). The controllers monitor and control the critical infrastructures, such as electric power grids and healthcare platforms, and continuously report back the system status to human operators. We present Zeus, a contactless embedded controller security monitor to ensure its execution control flow integrity. Zeus leverages the electromagnetic emission by the PLC circuitry during the execution of the controller programs. Zeus's contactless execution tracking enables non-intrusive monitoring of security-critical controllers with tight real-time constraints. Those devices often cannot tolerate the cost and performance overhead that comes with additional traditional hardware or software monitoring modules. Furthermore, Zeus provides an air-gap between the monitor (trusted computing base) and the target (potentially compromised) PLC. This eliminates the possibility of the monitor infection by the same attack vectors. Zeus monitors for control flow integrity of the PLC program execution. Zeus monitors the communications between the human machine interface and the PLC, and captures the control logic binary uploads to the PLC. Zeus exercises its feasible execution paths, and fingerprints their emissions using an external electromagnetic sensor. Zeus trains a neural network for legitimate PLC executions, and uses it at runtime to identify the control flow based on PLC's electromagnetic emissions. We implemented Zeus on a commercial Allen Bradley PLC, which is widely used in industry, and evaluated it on real-world control program executions. Zeus was able to distinguish between different legitimate and malicious executions with 98.9% accuracy and with zero overhead on PLC execution by design.
Critical resource sharing among multiple entities in a processing system is inevitable, which in turn calls for the presence of appropriate authentication and access control mechanisms. Generally speaking, these mechanisms are implemented via trusted software "policy checkers" that enforce certain high level application-specific "rules" to enforce a policy. Whether implemented as operating system modules or embedded inside the application ad hoc, these policy checkers expose additional attack surface in addition to the application logic. In order to protect application software from an adversary, modern secure processing platforms, such as Intel's Software Guard Extensions (SGX), employ principled hardware isolation to offer secure software containers or enclaves to execute trusted sensitive code with some integrity and privacy guarantees against a privileged software adversary. We extend this model further and propose using these hardware isolation mechanisms to shield the authentication and access control logic essential to policy checker software. While relying on the fundamental features of modern secure processors, our framework introduces productive software design guidelines which enable a guarded environment to execute sensitive policy checking code - hence enforcing application control flow integrity - and afford flexibility to the application designer to construct appropriate high-level policies to customize policy checker software.
We report on our discovery of an algorithmic flaw in the construction of primes for RSA key generation in a widely-used library of a major manufacturer of cryptographic hardware. The primes generated by the library suffer from a significant loss of entropy. We propose a practical factorization method for various key lengths including 1024 and 2048 bits. Our method requires no additional information except for the value of the public modulus and does not depend on a weak or a faulty random number generator. We devised an extension of Coppersmith's factorization attack utilizing an alternative form of the primes in question. The library in question is found in NIST FIPS 140-2 and CC\textasciitildeEAL\textasciitilde5+ certified devices used for a wide range of real-world applications, including identity cards, passports, Trusted Platform Modules, PGP and tokens for authentication or software signing. As the relevant library code was introduced in 2012 at the latest (and probably earlier), the impacted devices are now widespread. Tens of thousands of such keys were directly identified, many with significant impacts, especially for electronic identity documents, software signing, Trusted Computing and PGP. We estimate the number of affected devices to be in the order of at least tens of millions. The worst cases for the factorization of 1024 and 2048-bit keys are less than 3 CPU-months and 100 CPU-years on single core of common recent CPUs, respectively, while the expected time is half of that of the worst case. The attack can be parallelized on multiple CPUs. Worse still, all susceptible keys contain a strong fingerprint that is verifiable in microseconds on an ordinary laptop – meaning that all vulnerable keys can be quickly identified, even in very large datasets.
For industrial control systems, ensuring the software integrity of their devices is a key security requirement. A pure software-based attestation solution is highly desirable for protecting legacy field devices that lack hardware root of trust (e.g., Trusted Platform Module). However, for the large population of field devices with ARM processors, existing software-based attestation schemes either incur long attestation time or are insecure. In this paper, we design a novel memory stride technique that significantly reduces the attestation time while remaining secure against known attacks and their advanced variants on ARM platform. We analyze the scheme's security and performance based on the formal framework proposed by Armknecht et al. [7] (with a necessary change to ensure its applicability in practical settings). We also implement memory stride on two models of real-world power grid devices that are widely deployed today, and demonstrate its superior performance.
In this paper we investigate whether and how hardware-based roots of trust, namely Trusted Platform Modules (TPMs) can improve the security of the communication protocol OPC UA (Open Platform Communications Unified Architecture) under reasonable assumptions, i.e. the Dolev-Yao attacker model. Our analysis shows that TPMs may serve for generating (RNG) and securely storing cryptographic keys, as cryptocoprocessors for weak systems, as well as for remote attestation. We propose to include these TPM functions into OPC UA via so-called ConformanceUnits, which can serve as building blocks of profiles that are used by clients and servers for negotiating the parameters of a session. Eventually, we present first results regarding the performance of a client-server communication including an additional OPC UA server providing remote attestation of other OPC UA servers.
The Trusted Platform Module (TPM) is an international standard for a security chip that can be used for the management of cryptographic keys and for remote attestation. The specification of the most recent TPM 2.0 interfaces for direct anonymous attestation unfortunately has a number of severe shortcomings. First of all, they do not allow for security proofs (indeed, the published proofs are incorrect). Second, they provide a Diffie-Hellman oracle w.r.t. the secret key of the TPM, weakening the security and preventing forward anonymity of attestations. Fixes to these problems have been proposed, but they create new issues: they enable a fraudulent TPM to encode information into an attestation signature, which could be used to break anonymity or to leak the secret key. Furthermore, all proposed ways to remove the Diffie-Hellman oracle either strongly limit the functionality of the TPM or would require significant changes to the TPM 2.0 interfaces. In this paper we provide a better specification of the TPM 2.0 interfaces that addresses these problems and requires only minimal changes to the current TPM 2.0 commands. We then show how to use the revised interfaces to build q-SDH-and LRSW-based anonymous attestation schemes, and prove their security. We finally discuss how to obtain other schemes addressing different use cases such as key-binding for U-Prove and e-cash.
We propose $μ$Leech, a new embedded trusted platform module for next generation power scavenging devices. Such power scavenging devices are already widely deployed. For instance, the Square point-of-sale reader uses the microphone/speaker interface of a smartphone for communications and as power supply. While such devices are used as trusted devices in security critical applications in the wild, they have not been properly evaluated yet. $μ$Leech can securely store keys and provide cryptographic services to any connected smart phone. Our design also facilitates physical security analysis by providing interfaces to facilitate acquisition of power traces and clock manipulation attacks. Thus $μ$Leech empowers security researchers to analyze leakage in next generation embedded and IoT devices and to evaluate countermeasures before deployment.
High accurate time synchronization is very important for many applications and industrial environments. In a computer network, synchronization of time for connected devices is provided by the Precision Time Protocol (PTP), which in principal allows for device time synchronization down to microsecond level. However, PTP and network infrastructures are vulnerable to cyber-attacks, which can de-synchronize an entire network, leading to potentially devastating consequences. This paper will focus on the issue of internal attacks on time synchronization networks and discuss how counter-measures based on public key infrastructures, trusted platform modules, network intrusion detection systems and time synchronization supervisors can be adopted to defeat or at least detect such internal attacks.
The urgent task of the organization of confidential calculations in crucial objects of informatization on the basis of domestic TPM technologies (Trusted Platform Module) is considered. The corresponding recommendations and architectural concepts of the special hardware TPM module (Trusted Platform Module) which is built in a computing platform are proposed and realize a so-called ``root of trust''. As a result it gave the organization the confidential calculations on the basis of domestic electronic base.
Most security software tools try to detect malicious components by cryptographic hashes, signatures or based on their behavior. The former, is a widely adopted approach based on Integrity Measurement Architecture (IMA) enabling appraisal and attestation of system components. The latter, however, may induce a very long time until misbehavior of a component leads to a successful detection. Another approach is a Dynamic Runtime Attestation (DRA) based on the comparison of binary code loaded in the memory and well-known references. Since DRA is a complex approach, involving multiple related components and often complex attestation strategies, a flexible and extensible architecture is needed. In a cooperation project an architecture was designed and a Proof of Concept (PoC) successfully developed and evaluated. To achieve needed flexibility and extensibility, the implementation facilitates central components providing attestation strategies (guidelines). These guidelines define and implement the necessary steps for all relevant attestation operations, i.e. measurement, reference generation and verification.
Creating and implementing fault-tolerant distributed algorithms is a challenging task in highly safety-critical industries. Using formal methods supports design and development of complex algorithms. However, formal methods are often perceived as an unjustifiable overhead. This paper presents the experience and insights when using TLA+ and PlusCal to model and develop fault-tolerant and safety-critical modules for TAS Control Platform, a platform for railway control applications up to safety integrity level (SIL) 4. We show how formal methods helped us improve the correctness of the algorithms, improved development efficiency and how part of the gap between model and implementation has been closed by translation to C code. Additionally, we describe how we gained trust in the formal model and tools by following a specific design process called property-driven design, which also implicitly addresses software quality metrics such as code coverage metrics.
Securing their critical documents on the cloud from data threats is a major challenge faced by organizations today. Controlling and limiting access to such documents requires a robust and trustworthy access control mechanism. In this paper, we propose a semantically rich access control system that employs an access broker module to evaluate access decisions based on rules generated using the organizations confidentiality policies. The proposed system analyzes the multi-valued attributes of the user making the request and the requested document that is stored on a cloud service platform, before making an access decision. Furthermore, our system guarantees an end-to-end oblivious data transaction between the organization and the cloud service provider using oblivious storage techniques. Thus, an organization can use our system to secure their documents as well as obscure their access pattern details from an untrusted cloud service provider.
This paper presents the foundations of secured and trusted architecture for the Internet of Things platforms, based on Secure Elements (SE). Some IoT networks could be managed by service providers, dealing with smart grids or healthcare. Many platforms are using DTLS or TLS protocols. Therefore SEs running such stacks could provide strong mutual authentication and secure communications. Three future research directions are illustrated by previous experiments. TLS/DTLS SE servers for objects, CoAP DTLS clients for SIM modules, and RACS authorization servers based on SE TLS servers.
Cyber-physical system integrity requires both hardware and software security. Many of the cyber attacks are successful as they are designed to selectively target a specific hardware or software component in an embedded system and trigger its failure. Existing security measures also use attack vector models and isolate the malicious component as a counter-measure. Isolated security primitives do not provide the overall trust required in an embedded system. Trust enhancements are proposed to a hardware security platform, where the trust specifications are implemented in both software and hardware. This distribution of trust makes it difficult for a hardware-only or software-only attack to cripple the system. The proposed approach is applied to a smart grid application consisting of third-party soft IP cores, where an attack on this module can result in a blackout. System integrity is preserved in the event of an attack and the anomalous behavior of the IP core is recorded by a supervisory module. The IP core also provides a snapshot of its trust metric, which is logged for further diagnostics.
The incorporation of security mechanisms to protect spacecraft's TT&c; payload links is becoming a constant requirement in many space missions. More advanced mission concepts will allow spacecrafts to have higher levels of autonomy, which includes performing key management operations independently of control centers. This is especially beneficial to support missions operating distantly from Earth. In order to support such levels of autonomy, key agreement is one approach that allows spacecrafts to establish new cryptographic keys as they deem necessary. This work introduces an approach based on a trusted platform module that allows for key agreement to be performed with minimal computational efforts and protocol iterations. Besides, it allows for opportunistic control center reporting while avoiding man-in-the-middle and replay attacks.
Ensuring security in the military applications of IoT is a big challenge. The main reasons for this state of affairs is that the sensor nodes of the network are usually mobile, use wireless links, have a small processing power and have a little energy resources. The paper presents the solution for cryptographic protection of transmission between sensor nodes in the data link layer and for cryptographic protection of data stored in the sensor node resources. For this purpose, the Trusted Platform Module (TPM) was used. The proposed solution makes it possible to build secure and fault tolerant sensor network. The following aspects were presented in the paper: the model of such a network, applied security solutions, analysis of the security in the network and selected investigation results of such a network were presented.
Cloud platforms can leverage Trusted Platform Modules to help provide assurance to clients that cloud-based Web services are trustworthy and behave as expected. We discuss a variety of approaches to providing this assurance, and we implement one approach based on the concept of a trustworthy certificate authority. TaoCA, our prototype implementation, links cryptographic attestations from a cloud platform, including a Trusted Platform Module, with existing TLS-based authentication mechanisms. TaoCA is designed to enable certificate authorities, browser vendors, system administrators, and end users to define and enforce a range of trust policies for web services. Evaluation of the prototype implementation demonstrates the feasibility of the design, illustrates performance tradeoffs, and serves as an end-to-end, proof-of-concept evaluation of underlying trustworthy computing abstractions. The proposed approach can be deployed incrementally and provides new benefits while retaining compatibility with the existing public key infrastructure used for TLS.
Notions like security, trust, and privacy are crucial in the digital environment and in the future, with the advent of technologies like the Internet of Things (IoT) and Cyber-Physical Systems (CPS), their importance is only going to increase. Trust has different definitions, some situations rely on real-world relationships between entities while others depend on robust technologies to gain trust after deployment. In this paper we focus on these robust technologies, their evolution in past decades and their scope in the near future. The evolution of robust trust technologies has involved diverse approaches, as a consequence trust is defined, understood and ascertained differently across heterogeneous domains and technologies. In this paper we look at digital trust technologies from the point of view of security and examine how they are making secure computing an attainable reality. The paper also revisits and analyses the Trusted Platform Module (TPM), Secure Elements (SE), Hypervisors and Virtualisation, Intel TXT, Trusted Execution Environments (TEE) like GlobalPlatform TEE, Intel SGX, along with Host Card Emulation, and Encrypted Execution Environment (E3). In our analysis we focus on these technologies and their application to the emerging domains of the IoT and CPS.
This paper has presented an approach of vTPM (virtual Trusted Platform Module) Dynamic Trust Extension (DTE) to satisfy the requirements of frequent migrations. With DTE, vTPM is a delegation of the capability of signing attestation data from the underlying pTPM (physical TPM), with one valid time token issued by an Authentication Server (AS). DTE maintains a strong association between vTPM and its underlying pTPM, and has clear distinguishability between vTPM and pTPM because of the different security strength of the two types of TPM. In DTE, there is no need for vTPM to re-acquire Identity Key (IK) certificate(s) after migration, and pTPM can have a trust revocation in real time. Furthermore, DTE can provide forward security. Seen from the performance measurements of its prototype, DTE is feasible.
Users of modern data-processing services such as tax preparation or genomic screening are forced to trust them with data that the users wish to keep secret. Ryoan protects secret data while it is processed by services that the data owner does not trust. Accomplishing this goal in a distributed setting is difficult because the user has no control over the service providers or the computational platform. Confining code to prevent it from leaking secrets is notoriously difficult, but Ryoan benefits from new hardware and a request-oriented data model. Ryoan provides a distributed sandbox, leveraging hardware enclaves (e.g., Intel's software guard extensions (SGX) [15]) to protect sandbox instances from potentially malicious computing platforms. The protected sandbox instances confine untrusted data-processing modules to prevent leakage of the user's input data. Ryoan is designed for a request-oriented data model, where confined modules only process input once and do not persist state about the input. We present the design and prototype implementation of Ryoan and evaluate it on a series of challenging problems including email filtering, heath analysis, image processing and machine translation.