Trojan

About: Trojan is a research topic. Over the lifetime, 2028 publications have been published within this topic receiving 33209 citations.

R2D2: Runtime reassurance and detection of A2 Trojan

Abstract: With the globalization of semiconductor industry, hardware security issues have been gaining increasing attention. Among all hardware security threats, the insertion of hardware Trojans is one of the main concerns. Meanwhile, many current Trojan detection solutions follow the assumption that the hardware Trojan itself should be composed of digital logic. This assumption is invalidated by recently proposed analog Trojans which are extremely small and can detect rare events. This paper proposes a runtime hardware Trojan detection method which is geared towards detecting such advanced Trojans. The principle of this method is to guard a set of concerned signals, and initiate a hardware interrupt request when abnormal toggling events occur in these guarded signals. To prove the effectiveness of this method, we design a processor based on ARMv7-A&R ISA, and insert an analog Trojan into the processor. We fabricated the design in the SMIC 130 nm process and demonstrate the effectiveness of the proposed methodology.

Side channels as building blocks

Abstract: Since the introduction of the first side-channel analyses in academia about 15 years ago, several physical attacks have been presented that exploit side-channel leakages to break implementations of cryptographic algorithms. This article deals with the same physical property of electronic devices, but focuses on the art of tailoring it for constructive uses. More precisely, two scenarios, i.e., hardware Trojans and IP watermarking, are illustrated in which the designer of an electronic circuit can add functionality by considering side channels as part of the available design space. Both applications use the same concept, i.e., deliberately leaking a secret through a side channel while keeping the introduced side channel hidden from adversaries and attackers. This article provides a broad overview of the existing works for both applications and should serve as a comprehensible introduction to the underlying field of research. This includes many subtle details that have not been discussed in literature yet, including existing shortcomings and possible improvements to the existing works. The solutions summarized in this article provide general guidelines for theorists and practitioners to use side channels constructively to achieve designs that are robust against detection and removal. Furthermore, we present an entirely new design of a Trojan side-channel. This architecture demonstrates the potential of a Trojan side-channel that is neatly tailored to the targeted implementation. The new design removes all non-invasive starting points a third party could use to analyze or get access to the secret-channel.

Trojans in the Solar Neighborhood

Abstract: About 20% of stars in the solar vicinity are in the Hercules stream, a bundle of stars that move together with a velocity distinct from the Sun. Its origin is still uncertain. Here, we explore the possibility that Hercules is made of trojans, stars captured at L4, one the Lagrangian points of the stellar bar. Using GALAKOS--a high-resolution N-body simulation of the Galactic disk--we follow the motions of stars in the co-rotating frame of the bar and confirm previous studies on Hercules being formed by stars in co-rotation resonance with the bar. Unlike previous work, we demonstrate that the retrograde nature of trojan orbits causes the asymmetry in the radial velocity distribution, typical of Hercules in the solar vicinity. We show that trojans remain at capture for only a finite amount of time, before escaping L4 without being captured again. We anticipate that in the kinematic plane the Hercules stream will de-populate along the bar major axis and be visible at azimuthal angles behind the solar vicinity with a peak towards L4. This test can exclude the OLR origin of the Hercules stream and be validated by Gaia DR3 and DR4.

An Introduction to the Dynamics of Trojan Asteroids

Abstract: The dynamics of Trojan asteroids constitutes one of the richest fields of celestial mechanics, as a real application of the three-body problem. It involves the L 4 and L 5 Lagrange points and the conditions of stability around these two points. In this chapter we propose to present the fundamentals of the dynamics of Trojan asteroids. After a brief historical overview, we come back to the definitions and characteristics of the collinear Lagrange points L 1, L 2, and L 3, as well as the triangular ones, L 4 and L 5. We show how observational data of Trojan asteroids have confirmed the existence of real bodies librating around these two last points. Then we focus on the linearization of the equations of motion around L 4 and L 5 from a general and purely theoretical point of view. In addition, we show how qualitative results can be extracted to describe the properties of Trojan asteroids. We complete our study by summarizing many previous and up-to-date investigations, which focus on their dynamical behavior.

Insights into the mind of a trojan designer: the challenge to integrate a trojan into the bitstream

Abstract: The threat of inserting hardware Trojans during the design, production, or in-field poses a danger for integrated circuits in real-world applications. A particular critical case of hardware Trojans is the malicious manipulation of third-party FPGA configurations. In addition to attack vectors during the design process, FPGAs can be infiltrated in a non-invasive manner after shipment through alterations of the bitstream. First, we present an improved methodology for bitstream file format reversing. Second, we introduce a novel idea for Trojan insertion.