Trusted Computing Group Research Articles

Mitigating Software Integrity Attacks With Trusted Computing in a Time Distribution Network

Time Distribution Networks (TDNs) evolve as new technologies occur to ensure more accurate, reliable, and secure timing information. These networks typically exploit several distributed time servers, organized in a master-slave architecture, that communicate via dedicated timing protocols. From the security perspective, timing data must be protected since its modification or filtering can lead to grave consequences in different time-based contexts, such as health, energy, finance, or transportation. Thus, adequate countermeasures must be employed in all the stages and systems handling timing data from its calculation until it reaches the final users. We consider a TDN offering highly accurate (nanosecond level) time synchronization through specific time unit devices that exploit terrestrial atomic or rubidium clocks and Global Navigation Satellite Systems (GNSS) receivers. Such devices are appealing targets for attackers, who might exploit various attack vectors to compromise their functionality. We individuate three possible software integrity attacks against time devices, and we propose a solution to counter them by exploiting the cryptographic Trusted Platform Module (TPM), defined and supported by the Trusted Computing Group. We used remote attestation software for cloud environments, namely the Keylime framework, to verify (periodically) the software daemons running on the time devices (or their configuration) from a trusted node. Experiments performed on a dedicated testbed set up in the ROOT project with customized time unit devices from Seven Solutions (currently Orolia Spain) allow us to demonstrate that exploiting TPMs and remote attestation in the TDNs is not only helpful but is fundamental for discovering some attacks that would remain otherwise undetected. Our work helps thus TDN operators build more robust, accurate, and secure time synchronization services.

PCs Take a Page From Xbox With Pluton

Microsoft’s Pluton is dedicated silicon that aims to strengthen the security and integrity of PCs; it is derived from the Xbox One video game console SoC which was designed in partnership between Microsoft and AMD. Pluton implements and extends the functionality of the Trusted Computing Group’s (TCG) Trusted Platform Module 2.0, protects keys as they move around the SoC using dedicated silicon referred to as Secure Hardware Cryptography Key, and implements the TCG’s Device Identifier Composition Engine and Microsoft’s Robust Internet of Things specifications to perform strong device attestation with a hardware root of trust. While Microsoft is following Apple and Google’s lead by integrating special-purpose silicon for secure cryptographic operations, it is taking a different approach by leveraging existing open standards and technologies. Microsoft’s Windows 11 is designed for a world where all PCs feature Pluton.

Emulating Trusted Platform Module 2.0 on Raspberry Pi 2

A computer hijacked by a malware may pretend that it is normal as usual and retrieve secrets from storage of itself and other victim computers. By adopting trusted computing technology a computer’s former health status cannot be forged. Computers can thus detect the change of health status of a hijacked computer and prevent the leakage of the secrets. As Trusted Computing Group (TCG) proposed Trusted Platform Module (TPM) specification, IBM implemented software TPM (sTPM) and utilities for engineer who wants to learn the operating principle of TPM. Meanwhile, the blooming of tiny size, but powerful, computers, e.g. Raspberry Pi 2 (Rpi2), attract ones to develop some dedicated applications on the computers. In this article, we report the verified steps for installing new sTPM version on RPi2. After the installation, we also test the functionality and evaluate the performance of the sTPM with some major TPM Commands. The real behaviour of and the traffic between the host computer and the emulated TPM can thus be learned easily.

IEEE Access Special Section Editorial: Trusted Computing

Trusted Computing (TC) is a technology developed and promoted by the Trusted Computing Group (TCG), and aims to enhance the overall security, privacy and trustworthiness of a variety of computing devices. The core of the trusted computing technologies of TCG is the Trusted Platform Module (TPM), a tamper-resistant module embedded in a platform, which is implemented by a TPM chip and designed to resist software attacks and moderate hardware attacks. TPM includes non-volatile storage, a set of Platform Configuration Registers (PCRs) and an engine for cryptographic operations. Based on TPM and TCG Software Stack (TSS), a suite of mechanisms can be realized, including memory curtaining, protected execution, secure I/O, sealed storage, platform measurement and remote attestation. As a fundamental secure computing module, TPM is the root trust module to establish security and trust in digital computing, communication and networking. Basically, it can support secure booting and trustworthy software installation, private data protection and Digital Rights Management (DRM), as well as remote attestation- based trusted communications and collaboration. There is significant research currently in the field of trusted computing, in both academia and industry. Recent efforts focus on TC module development and extension, trustworthy software assurance, Trusted Execution Environment (TEE), trusted collaboration and trusted storage. The recent advance of Intel Software Guard Extensions (Intel® SGX) offers hardware-assistant TEE, which allows user code execution in a private region of memory, called enclave, in an untrusted third party. This technology attracts special attention and motivates innovations of many applications.

EMULATING TRUSTED PLATFORM MODULE 2.0 ON RASPBERRY PI 2

A computer hijacked by a malware may pretend that it is normal as usual and retrieve secrets from storage of itself and other victim computers. By adopting trusted computing technology a computer’s former health status cannot be forged. Computers can thus detect the change of health status of a hijacked computer and prevent the leakage of the secrets. As Trusted Computing Group (TCG) proposed Trusted Platform Module (TPM) specification, IBM implemented software TPM (sTPM) and utilities for engineer who wants to learn the operating principle of TPM. Meanwhile, the blooming of tiny size, but powerful, computers, e.g. Raspberry Pi 2 (Rpi2), attract ones to develop some dedicated applications on the computers. In this article, we report the verified steps for installing new sTPM version on RPi2. After the installation, we also test the functionality and evaluate the performance of the sTPM with some major TPM Commands. The real behaviour of and the traffic between the host computer and the emulated TPM can thus be learned easily.

Mobile Network Security and Privacy in WSN

This paper discuss the term threats, attacks and vulnerabilities in Wireless Sensor Networks followed by a model that relates the three entities. Based on the model, a framework of Trusted Wireless Sensor node is presented consisting of two major sections which are platform security enhancement and Trusted Authentication protocol to enhance sensor nodes security features and confirm the fidelity of node joining the network respectively. The design of the framework is in line with Trusted Computing Group specifications toward trusted platform implementation. Finally, brief analysis on the proposed framework is presented.

Hybrid Trust Chain Security Model with Cloud Computing Based on Smart Grid

The paper proposes a hybrid trust chain model with cloud computing based on smart grid, for the purpose of enhancing the ability of smart grid cloud computing system to deal with most malicious attacks and reduce the security risk. The model merges the trust transfer model and the separation model, based on a set of trust chain establishment scheme defined by Trusted Computing Group (TCG), and improves the traditional chain and star trust model, in order to boot and establish a trusted secure computing environment. Proved by examples, the hybrid trust chain security model puts the security of cloud computing on the trusted computing platform, which has significant effects on improving the credibility of the computer system, increasing the security of the cloud foundation and ensuring the integrity of the information.

Design and implementation of an attestation protocol for measured dynamic behavior

Security of applications running on remote devices has become an essential need of enterprises. For this purpose, several software-based solutions have been proposed. However, it has been observed that software solutions are vulnerable to several kinds of attacks. Moreover, they cannot protect and monitor all parts of the system. To overcome this problem, researchers have proposed to monitor a target system from an isolated hardware and store system’s sensitive information in its tamper-proof memory locations. To realize such a solution, Trusted Computing Group (TCG) has proposed the specifications of a co-processor called Trusted Platform Module which is widely available in commodity hardware. Integrity Measurement Architecture is one of the well-known static techniques that brings TCG’s attestation from kernel to the application level. However, this method cannot measure runtime behavior of applications, which is necessary to detect runtime attacks such as buffer overflow and return-oriented programming. In this paper, we have extended the base work which aims to detect runtime vulnerabilities. Current high-level-based attestation protocol has been extended for dynamic behavior collection and verification, and the dynamic behavior is verified via several machine learning algorithms. Our results justify the use of this approach and show that a high rate detection was achieved for datasets of real-world vulnerabilities in the popular Firefox browser.

Trust in IoT: dynamic remote attestation through efficient behavior capture

The Internet of Things (IoT) is a latest concept of machine-to-machine communication, that also gave birth to several information security problems. Many traditional software solutions fail to address these security issues such as trustworthiness of remote entities. Remote attestation is a technique given by Trusted Computing Group (TCG) to monitor and verify this trustworthiness. In this regard, various remote validation methods have been proposed. However, static techniques cannot provide resistance to recent attacks e.g. the latest Heartbleed bug, and the recent high profile glibc attack on Linux operating system. In this research, we have designed and implemented a lightweight Linux kernel security module for IoT devices that is scalable enough to monitor multiple applications in the kernel space. The newly built technique can measure and report multiple application’s static and dynamic behavior simultaneously. Verification of behavior of applications is performed via machine learning techniques. The result shows that deviating behavior can be detected successfully by the verifier.

Accountability in Cloud Computing by Means of Chain of Trust

Cloud computing offers various services in form of infrastructure, platform, and software to meet the consumer requirements. It is radically changing how information technology services are created, delivered, accessed, and managed. However, this swift has prompted concerns regarding security and privacy due to cloud computing characteristics such as the multi-tenancy, elasticity, and layered architecture. One of the major challenge is to offer accountability in cloud services across all the dependencies. When one entity relies on other entities for functioning, it creates a dependency in system and makes it difficult to sort out the responsible entity among them. In this paper, we analyze the problem of creating accountable cloud services. We utilize basic functionality provided by Trusted Computing Group (TCG) in form of chain of trust (CoT) by securely recording identities (of entities). We propose a solution that modifies existing chain of trust to build accountable cloud computing. We explore dependency relationship in building reliable chain of trust in cloud and define it for better implementation.

Security Analysis and Improvement of the TNC IF-T Protocol Binding for Tunneled EAP Methods

The TNC IF-T Protocol Binding for Tunneled EAP Methods (TIPBTEM) is specified by Trusted Computing Group (TCG) for TNC assessment (i.e., PlatformAuthentication) exchanges. Because the TIPBTEM includes Platform-Authentication in addition to the usual user authentication, it differs greatly from the traditional security protocols in terms of security requirements. To analyze the security of the TIPBTEM correctly, the extended strand space model (SSM) for trusted network access protocols is applied in this paper. And it is pointed out that the TIPBTEM cannot prevent manin-the-middle (MITM) attacks in some cases. To eliminate MITM attacks, the unsecure cases of the TIPBTEM are improved based on cryptographic binding. And then it is showed that these improved TIPBTEM cases can resist MITM attacks in the extended SSM.

Towards a New Framework for TPM Compliance Testing

Trusted Computing Group (TCG) has proposed the Trusted Computing (TC) concept. Subsequently, TC becomes a common base for many new computing platforms, called Trusted Platform (TP) architecture (hardware and software) that, practically, has a built-in trusted hardware component mounted at the hardware layer and a corresponding trusted software component installed at the operating system level. The trusted hardware component is called Trusted Platform Module (TPM) whose specification has been issued by TCG group and it is implemented by the industry as a tamper-resistant integrated circuit. In practice, the security of an IT TPM-enabled system relies on the correctness of its mounted TPM. Thus, TPM testing is urgently needed to assist in building confidence of the users on the security functionality provided by the TPM. This paper presents the state of the art of the modelling methods being used in the TPM compliance testing as well as it demonstrates some of the important attacks against TPM. Finally, the paper proposes new framework criteria for TPM Testing that aim at increasing the quality of TPM testing.

A delegation based cross trusted domain direct anonymous attestation scheme

Direct Anonymous Attestation (DAA) is a complex cryptographic protocol for remote attestation and provides both signer authentication and privacy. It was adopted by the Trusted Computing Group (TCG) as a technical standard. However, the DAA scheme in TCG specifications is designed for the single trusted domain attestation, and cannot be deployed in different trusted domain directly. It limits its application range in mobile networks, cloud computing, Internet of Things networks when users and authentication servers belong to different domains. Based on delegation of the trusted relationship, a new cross trusted domain direct anonymous attestation scheme is proposed in this paper. The proxy signature is used for trusted relationship delegation among different domains, and the DAA method is used for the computation platform authentication when a trusted platform accessing different trusted domains. Then the authentication protocol is designed and analyzed under Canetti–Krawczyk (CK) model for the platform remote attestation. The further analysis shows that our proposal can resist platform masquerade attacks and replay attacks, and the authentication protocol is provably secure. The security of the DAA remote attestation system is enhanced by the session key agreement. Finally, a prototype implementation and some experiments are given, the results show that the proposed scheme is effective and suitable for cross domain applications.

On the provable security of TPM2.0 cryptography APIs

Trusted platform module (TPM), core of trusted computing technique, is one of the most prevalent security chips in the world. In 2013, Trusted Computing Group formally upgraded TPM specification to version 2.0, and introduced a comprehensive and powerful trusted computing technique architecture. However, the new specification is rather complex and thus error prone, which makes it necessary to evaluate TPM2.0's security. In this paper, we focus on cryptography subsystem of TPM2.0. We define the first computation model of TPM2.0 cryptography APIs, and prove their security in this strong model using game sequence and simulation. This proof provides high level confidence on security guarantee of TPM2.0 cryptography subsystem. We also carry out experiments on these APIs and compare them with previous version. The experiment shows that flexibility of TPM2.0 does not reduce its performance, meanwhile, real TPM2.0 product still needs to be improved.

An efficient anonymous remote attestation scheme for trusted computing based on improved CPK

The platform remote attestation (RA) is one of the main features of trusted computing platform proposed by the trusted computing group (TCG). The privacy certificate authority (CA) solution of RA requires users to pay for multiple certificates, and the direct anonymous attestation (DAA) solution leads to inefficiency. TCG RA also suffers from limitations of platform configuration privacy. This paper proposed a RA scheme based on an improved combined public key cryptography (ICPK) (abbreviated to RA-ICPK). RA-ICPK is a certificate-less scheme without using public key infrastructure CA signature or DAA signature, which combines commitment scheme, zero-knowledge proof and ring signature (RS) to own the property of unforgeability and privacy. RA-ICPK is mainly based on elliptic curve cryptography without bilinear pair computing, and only carries out zero-knowledge proof one time. RA-ICPK need not depend on trusted third parties to check trusted platform modules identity and integrity values revocations.

DESIGN AND IMPLEMENTATION OF THE TPM USER AUTHENTICATION MODEL

The Trusted Computing Group (TCG) has introduced the Trusted Platform Module (TPM) as a solution to assure end users of their privacy and confidentiality. Although the TPM is designed to prevent software attacks, the TPM itself is vulnerable to physical attacks that could enable intruders to gain access to confidential data. In general, the TPM provides an ID and implements a password identification technique to prevent unauthorized users from gaining access to the TPM. The TPM user authentication is carried out by the TPM itself, which exposes the TPM to direct risk as highly skilled intruders can break the authentication line of defence and gain access to the TPM. The process of encrypting and decrypting information, especially when asymmetric algorithms are used, is viewed as a process that consumes time and resources, which decreases the speed of the computer. In order to solve the problems, a TPM User Authentication Model (TPM-UAM) that can provide the TPM with a higher level of security and resistance against physical attacks has been proposed as we proposed in our previous research paper (Alshar’e et al., 2014). The technique is based on biometric authentication to prove the identity of the users and to allow the process of authentication to happen at an independent platform using virtualization that will keep the TPM out of reach until a user is completely verified and approved. The TPM-UAM is able to provide a more satisfactory level of confidence for data and processes that can be rated as highly confidential and private. The model was successfully developed and tested and the results confirmed the model efficiency and ability to secure TPM and all functions have been confirmed to be working perfectly according to what they were designed for. This paper describes the design and implementation of TPM-UAM system based on the proposed authentication model, virtualization has been implemented to create authentication platform to prevent direct interaction with TPM and biometrics has been implemented to verify identities and supervise running TPM, the system testing results in confirming the system functionality and ability to secure and protect TPM.

Trusted mobile model based on DTE technology

Due to increasing demands for mobile security, the Trusted Computing Group organized a special group--Mobile Phone Working Group (MPWG) to deal with mobile security specification business. Though M...

A USER PROTECTION MODEL FOR THE TRUSTED COMPUTING ENVIRONMENT

Information security presents a huge challenge for both individuals and organizations. The Trusted Computing Group (TCG) has introduced the Trusted Platform Module (TPM) as a solution to end-users to ensure their privacy and confidentiality. TPM has the role of being the root of trust for systems and users by providing protected storage that is accessible only within TPM and thus, protects computers against unwanted access. TPM is designed to prevent software attacks with minimal consideration being given toward physical attacks. Therefore, TPM focus on PIN password identification to control the physical presence of a user. The PIN Password method is not the ideal user verification method. Evil Maid is one of the attacking methods where a piece of code can be loaded and hidden in the boot loader before loading TPM. The code will then collects confidential information at the next boot and store it or send it to attackers via the network. In order to solve this problem, a number of solutions have been proposed. However, most of these solutions does not provide sufficient level of protection to TPM. In this study we introduce the TPM User Authentication Model (TPM-UAM) that could assist in protecting TPM against physical attack and thus increase the security of the computer system. The proposed model has been evaluated through a focus group discussion consisting of a number of experts. The expert panel has confirmed that the proposed model is sufficient to provide expected level of protection to the TPM and to assist in preventing physical attack against TPM.

Analysis of two authorization protocols using Colored Petri Nets

To prevent unauthorized access to protected trusted platform module (TPM) objects, authorization protocols, such as the object-specific authorization protocol (OSAP), have been introduced by the trusted computing group (TCG). By using OSAP, processes trying to gain access to the protected TPM objects need to prove their knowledge of relevant authorization data before access to the objects can be granted. Chen and Ryan's 2009 analysis has demonstrated OSAP's authentication vulnerability in sessions with shared authorization data. They also proposed the Session Key Authorization Protocol (SKAP) with fewer stages as an alternative to OSAP. Chen and Ryan's analysis of SKAP using ProVerif proves the authentication property. The purpose of this paper was to examine the usefulness of Colored Petri Nets (CPN) and CPN Tools for security analysis. Using OSAP and SKAP as case studies, we construct intruder and authentication property models in CPN. CPN Tools is used to verify the authentication property using a Dolev---Yao-based model. Verification of the authentication property in both models using the state space tool produces results consistent with those of Chen and Ryan.

Towards a trusted HDFS storage platform: Mitigating threats to Hadoop infrastructures using hardware-accelerated encryption with TPM-rooted key protection

As a follow-on to the authors' previous work, this paper further expands on the concept of creating a trusted Apache Hadoop Distributed File System (HDFS). We discuss our motivation and evaluate a threat model for HDFS, and address a set of common security concerns within HDFS through infrastructure and software involving data-at-rest encryption and integrity validation. To accomplish these goals, we make use of technology from the Trusted Computing Group, such as the pervasively available Trusted Platform Module. In addition, we discuss our design considerations in building an encryption framework for Hadoop in a trustworthy manner, and describe the results of our experiments creating an encryption scheme for Hadoop utilizing hardware key protections and AES-NI for encryption acceleration. As part of this design we evaluate the recently implemented crypto framework for Hadoop and independently test the performance claims of AES-NI regarding mitigating performance overhead.