Biblio

The notion of integrated circuit split manufacturing which delegates the front-end-of-line (FEOL) and back-end-of-line (BEOL) parts to different foundries, is to prevent overproduction, piracy of the intellectual property (IP), or targeted insertion of hardware Trojans by adversaries in the FEOL facility. In this work, we challenge the security promise of split manufacturing by formulating various layout-level placement and routing hints as vector- and image-based features. We construct a sophisticated deep neural network which can infer the missing BEOL connections with high accuracy. Compared with the publicly available network-flow attack [1], for the same set of ISCAS-85benchmarks, we achieve 1.21× accuracy when splitting on M1 and 1.12× accuracy when splitting on M3 with less than 1% running time.

The design process of smart Consumer Electronics (CE) devices heavily relies on reusable Intellectual Property (IP) cores of Digital Signal Processor (DSP) and Multimedia Processor (MP). On the other hand, due to strict competition and rivalry between IP vendors, the problem of ownership conflict and IP piracy is surging. Therefore, to design a secured smart CE device, protection of DSP/MP IP core is essential. Embedding a robust IP owner's signature can protect an IP core from ownership abuse and forgery. This paper presents a covert signature embedding process for DSP/MP IP core at Register-transfer level (RTL). The secret marks of the signature are distributed over the entire design such that it provides higher robustness. For example for 8th order FIR filter, it incurs only between 6% and 3% area overhead for maximum and minimum size signature respectively compared to the non-signature FIR RTL design but with significantly enhanced security.

Due to globalization of Integrated Circuit (IC) design flow, Intellectual Property (IP) cores have increasingly become susceptible to various hardware threats such as Trojan insertion, piracy, overbuilding etc. An IP core can be secured against these threats using functional obfuscation based security mechanism. This paper presents a functional obfuscation of digital signal processing (DSP) core for consumer electronics systems using a novel IP core locking block (ILB) logic that leverages the structure of flip-flops and combinational circuits. These ILBs perform the locking of the functionality of a DSP design and actuate the correct functionality only on application of a valid key sequence. In existing approaches so far, executing exhaustive trials are sufficient to extract the valid keys from an obfuscated design. However, proposed work is capable of hindering the extraction of valid keys even on exhaustive trials, unless successfully applied in the first attempt only. In other words, the proposed work drastically reduces the probability of obtaining valid key of a functionally obfuscated design in exhaustive trials. Experimental results indicate that the proposed approach achieves higher security and lower design overhead than previous works.

Security of transient fault secured IP cores against piracy, false claim of ownership can be achieved during high level synthesis, especially when handling DSP or multimedia cores. Though watermarking that involves implanting a vendor defined signature onto the design can be useful, however research has shown its limitations such as less designer control, high overhead due to extreme dependency on signature size, combination and encoding rule. This paper proposes an alternative paradigm called `hardware steganography' where hidden additional designer's constraints are implanted in a fault secured IP core using entropy thresholding. In proposed hardware steganography, concealed information in the form of additional edges having a specific entropy value is embedded in the colored interval graph (CIG). This is a signature free approach and ensures high designer control (more robustness and stronger proof of authorship) as well as lower overhead than watermarking schemes used for DSP based IP cores.

Locking the functionality of an integrated circuit (IC) thwarts attacks such as intellectual property (IP) piracy, hardware Trojans, overbuilding, and counterfeiting. Although functional locking has been extensively investigated, locking the performance of an IC has been little explored. In this paper, we develop provably-secure performance locking, where only on applying the correct key the IC shows superior performance; for an incorrect key, the performance of the IC degrades significantly. This leads to a new business model, where the companies can design a single IC capable of different performances for different users. We develop mathematical definitions of security and theoretically, and experimentally prove the security against the state-of-the-art-attacks. We implemented performance locking on a FabScalar microprocessor, achieving a degradation in instructions per clock cycle (IPC) of up to 77% on applying an incorrect key, with an overhead of 0.6%, 0.2%, and 0% for area, power, and delay, respectively.

Reliance on off-site untrusted fabrication facilities has given rise to several threats such as intellectual property (IP) piracy, overbuilding and hardware Trojans. Logic locking is a promising defense technique against such malicious activities that is effected at the silicon layer. Over the past decade, several logic locking defenses and attacks have been presented, thereby, enhancing the state-of-the-art. Nevertheless, there has been little research aiming to demonstrate the applicability of logic locking with large-scale multi-million-gate industrial designs consisting of multiple IP blocks with different security requirements. In this work, we take on this challenge to successfully lock a multi-million-gate system-on-chip (SoC) provided by DARPA by taking it all the way to GDSII layout. We analyze how specific features, constraints, and security requirements of an IP block can be leveraged to lock its functionality in the most appropriate way. We show that the blocks of an SoC can be locked in a customized manner at 0.5%, 15.3%, and 1.5% chip-level overhead in power, performance, and area, respectively.