Contactless Electromagnetic Active Attack on Ring Oscillator Based True Random Number Generator

International audienceTrue random number generators (TRNGs) are ubiquitous in data security as one of basic cryptographic primitives. They are primarily used as generators of con fidential keys, to initialize vectors, to pad values, but also as random masks generators in some side channel attacks countermeasures. As such, they must have good statistical properties, be unpredictable and robust against attacks. This paper presents a contactless and local active attack on ring oscillators (ROs) based TRNGs using electromagnetic fields. Experiments show that in a TRNG featuring fifty ROs, the impact of a local electromagnetic emanation on the ROs is so strong, that it is possible to lock them on the injected signal and thus to control the monobit bias of the TRNG output even when low power electromagnetic fields are exploited. These results confi rm practically that the electromagnetic waves used for harmonic signal injection may represent a serious security threat for secure circuits that embed RO-based TRNG

Electromagnetic Transmission of Intellectual Property Data to Protect FPGA Designs

International audienceOver the past 10 years, the designers of intellectual properties(IP) have faced increasing threats including cloning, counterfeiting, andreverse-engineering. This is now a critical issue for the microelectronicsindustry. The design of a secure, efficient, lightweight protection scheme fordesign data is a serious challenge for the hardware security community. In thiscontext, this chapter presents two ultra-lightweight transmitters using sidechannel leakage based on electromagnetic emanation to send embedded IPidentity discreetly and quickl

ElectroMagnetic Analysis and Fault Injection onto Secure Circuits

International audienceImplementation attacks are a major threat to hardware cryptographic implementations. These attacks exploit the correlation existing between the computed data and variables such as computation time, consumed power, and electromagnetic (EM) emissions. Recently, the EM channel has been proven as an effective passive and active attack technique against secure implementations. In this paper, we review the recent results obtained on this subject, with a particular focus on EM as a fault injection tool

Design and validation of a platform for electromagnetic fault injection

Security is acknowledged as one of the main challenges in the design and deployment of embedded circuits. Devices need to operate on-the-field safely and correctly, even when at physical reach of potential adversaries. One of the most powerful techniques to compromise the correct functioning of a device are fault injection attacks. They enable an active adversary to trigger errors on a circuit in order to bypass security features or to gain knowledge of security-sensitive information. There are several methods to induce such errors. In this work we focus on the injection of faults through the electromagnetic (EM) channel. In particular, we document our efforts towards building a suitable platform for EM pulse injection. We design a pulse injection circuit that can provide currents over 20 A to an EM injector in order to generate abrupt variations of the EM field on the vicinity of a circuit. We validate the suitability of our platform by applying a well-know attack on an embedded 8-bit microcontroller implementing the AES block cipher. In particular, we show how to extract the AES secret cryptographic keys stored in the device by careful injection of faults during the encryption operations and simple analysis of the erroneous outputs.Peer ReviewedPostprint (published version

A PUF based on transient effect ring oscillator and insensitive to locking phenomenon

International audienceThis paper presents a new silicon physical unclonable function (PUF) based on a transient effect ring oscillator (TERO). The proposed PUF has state of the art PUF characteristics with a good ratio of PUF response variability to response length. Unlike RO-PUF, it is not sensitive to the locking phenomenon, which challenges the use of ring oscillators for the design of both PUF and TRNG. The novel architecture using differential structures guarantees high stability of the TERO-PUF. The area of the TERO-PUF is relatively high, but is still comparable with other PUF designs. However, since the same piece of hardware can be used for both PUF and random number generation, the proposed principle offers an interesting low area mixed solution

On the assumption of mutual independence of jitter realizations in P-TRNG stochastic models

International audienceSecurity in true random number generation in cryptography is based on entropy per bit at the generator output. The entropy is evaluated using stochastic models. Several recent works propose stochastic models based on assumptions related to selected physical analog phenomena such as noise or jittery signal and on the knowledge of the principle of randomness extraction from the obtained analog signal. However, these assumptions simplify often considerably the underlying analog processes, which include several noise sources. In this paper, we present a new comprehensive multilevel approach, which enables to build the stochastic model based on detailed analysis of noise sources starting at transistor level and on conversion of the noise to the clock jitter exploited at the generator level. Using this approach, we can estimate proportion of the jitter coming only from the thermal noise, which is included in the total clock jitter

Teaching FPGA Security

International audienceTeaching FPGA security to electrical engineering students is new at graduate level. It requires a wide field of knowledge and a lot of time. This paper describes a compact course on FPGA security that is available to electrical engineering master's students at the Saint-Etienne Institute of Telecom, University of Lyon, France. It is intended for instructors who wish to design a new course on this topic. The paper reviews the motivation for the course, the pedagogical issues involved, the curriculum, the lab materials and tools used, and the results. Details are provided on two original lab sessions, in particular, a compact lab that requires students to perform differential power analysis of FPGA implementation of the AES symmetric cipher. The paper gives numerous relevant references to allow the reader to prepare a similar curriculum

Side-channel attacks and countermeasures in the design of secure IC's devices for cryptographic applications

Abstract--- A lot of devices which are daily used have to guarantee the retention of sensible data. Sensible data are ciphered by a secure key by which only the key holder can get the data. For this reason, to protect the cipher key against possible attacks becomes a main issue. The research activities in hardware cryptography are involved in finding new countermeasures against various attack scenarios and, in the same time, in studying new attack methodologies. During the PhD, three different logic families to counteract Power Analysis were presented and a novel class of attacks was studied. Moreover, two different activities related to Random Numbers Generators have been addressed