Paper 2019/928

Blockchain-enabled Cryptographically-secure Hardware Obfuscation

Fatemeh Ganji, Shahin Tajik, Jean-Pierre Seifert, and Domenic Forte

Abstract

Among numerous applications, besides cryptocurrencies, the Blockchain offers inherent properties beneficial for the management of supply chains, where data is shared between trusted and untrusted parties. Electronics supply chain serves as a prime example of such chains, where one of the major players, i.e., a foundry, can be untrusted. Hardware obfuscation techniques, namely logic locking, and IC camouflaging have been developed to mislead an adversary aiming at reverse- engineering and Intellectual Property (IP) piracy. However, virtually all existing hardware obfuscation schemes developed over the last decade have been shown to be vulnerable to various attacks. The success of these attacks has been relying on either a lack of thorough, cryptographically-secure obfuscation schemes or an incorrect assumption widely made, i.e., the existence of an ideal tamper- and read-proof memory to store the key. To overcome these shortcomings, this paper proposes a novel, Blockchain-enabled, cryptographically-secure hardware obfuscation schemes being compatible with current circuit synthesis and fabrication tools. In this regard, rather than solely monitoring the supply chain via the Blockchain, the security of the obfuscation is guaranteed by Proof-of-Stack Blockchain protocols and witness encryption schemes. Furthermore, with the help of our construction, we can realize one-time and pay-per-use hardware, where a user can use the electronic circuit for a limited amount of time.