On the Duality of Probing and Fault Attacks

In this work we investigate the problem of simultaneous privacy and integrity protection in cryptographic circuits. We consider a white-box scenario with a powerful, yet limited attacker. A concise metric for the level of probing and fault security is introduced, which is directly related to the capabilities of a realistic attacker. In order to investigate the interrelation of probing and fault security we introduce a common mathematical framework based on the formalism of information and coding theory. The framework unifies the known linear masking schemes. We proof a central theorem about the properties of linear codes which leads to optimal secret sharing schemes. These schemes provide the lower bound for the number of masks needed to counteract an attacker with a given strength. The new formalism reveals an intriguing duality principle between the problems of probing and fault security, and provides a unified view on privacy and integrity protection using error detecting codes. Finally, we introduce a new class of linear tamper-resistant codes. These are eligible to preserve security against an attacker mounting simultaneous probing and fault attacks

New Paradigms for Access Control in Constrained Environments

International audienceThe Internet of Things (IoT) is here, more than 10 billion units are already connected and five times more devices are expected to be deployed in the next five years. Technological standarization and the management and fostering of rapid innovation by governments are among the main challenges of the IoT. However, security and privacy are the key to make the IoT reliable and trusted. Security mechanisms for the IoT should provide features such as scalability, interoperability and lightness. This paper adresses authentication and access control in the frame of the IoT. It presents Physical Unclonable Functions (PUF), which can provide cheap, secure, tamper-proof secret keys to authentify constrained M2M devices. To be successfully used in the IoT context, this technology needs to be embedded in a standardized identity and access management framework. On the other hand, Embedded Subscriber Identity Module (eSIM) can provide cellular connectivity with scalability, interoperability and standard compliant security protocols. The paper discusses an authorization scheme for a constrained resource server taking advantage of PUF and eSIM features. Concrete IoT uses cases are discussed (SCADA and building automation)

Secured Hardware Design - an Overview

Security is a prime concern in the design of a wide variety of embedded systems and security processors. So the customer security devices such as smart cards and security processors are prone to attack and there are on going research to protect these devices from attackers who intend to extract key information from these devices. Also an active attacker can induce errors during computation and exploit the faulty result to extract the key information embedded in the processor. Due to the design time issues weakness in the design is often revealed in the manufactured chips. Also because the post- manufacture security evaluation is time consuming and expensive, these security issues have to be considered at the design phase. This paper outlines some of the hardware attacks and provides a general idea of the process of these attacks

A HOLISTIC APPROACH FOR SECURITY REQUIREMENT SPECIFICATION FOR LOW-COST, DISTRIBUTED UBIQUITOUS SYSTEMS

The class of low-cost, distributed ubiquitous systems represents a computing mode where a system has small, inexpensive networked processing devices, distributed at all scales throughout business activities and everyday life. The unique features of such a class of ubiquitous systems make the security analysis different from that for the centralized computing paradigms. This paper presents a holistic approach for security requirement analysis for low cost, distributed ubiquitous systems. Rigorous security analysis needs both quantitative and qualitative approaches to produce the holistic view and the robust data regarding the security features that a system must have in order to meet users’ security expectations. Our framework can assist system administrators to specify key security properties for a low-cost, distributed ubiquitous system and to define the specific security requirements for such a system. We applied Bayesian network and stochastic process algebra to incorporate probabilistic analysis to the framework

Keeping Secrets in Hardware: the Microsoft Xbox(TM) Case Study

This paper discusses the hardware foundations of the cryptosystem employed by the Xbox(TM) video game console from Microsoft. A secret boot block overlay is buried within a system ASIC. This secret boot block decrypts and verifies portions of an external FLASH-type ROM. The presence of the secret boot block is camouflaged by a decoy boot block in the external ROM. The code contained within the secret boot block is transferred to the CPU in the clear over a set of high-speed busses where it can be extracted using simple custom hardware. The paper concludes with recommendations for improving the Xbox security system. One lesson of this study is that the use of a high-performance bus alone is not a sufficient security measure, given the advent of inexpensive, fast rapid prototyping services and high-performance FPGAs