High-Assurance Cryptographic Hardware from Untrusted Components
Vasilios Mavroudis
Abstract:
The semiconductor industry is fully globalized and integrated circuits (ICs) are commonly defined, designed and fabricated in different premises across the world. This reduces production costs, but also exposes ICs to supply chain attacks, where insiders introduce malicious circuitry into the final products. Additionally, despite extensive post-fabrication testing, it is not uncommon for ICs with subtle fabrication errors to make it into production systems. While many systems may be able to tolerate a few byzantine components, this is not the case for cryptographic hardware, storing and computing on confidential data. For this reason, many error and backdoor detection techniques have been proposed over the years. So far all attempts have been either quickly circumvented, or come with unrealistically high manufacturing costs and complexity.
In this talk, we will present a practical high-assurance architecture that uses commercial off-the-shelf (COTS) hardware, and provides strong security guarantees, even in the presence of multiple malicious or faulty components. The key idea is to combine protective-redundancy with modern threshold cryptographic techniques to build a system tolerant to hardware trojans and errors. We will also demonstrate our Hardware Security Module that provides the highest level of assurance possible with COTS components. Specifically, we employ more than a hundred COTS secure crypto-coprocessors, verified to FIPS140-2 Level 4 tamper-resistance standards, and use them to realize high-confidentiality random number generation, key derivation, public key decryption and signing. Our experiments show a reasonable computational overhead (less than 1% for both Decryption and Signing) and an exponential increase in backdoor-tolerance as more ICs are added. This talk is based on our CCS 2017 paper and the project website is: https://backdoortolerance.org
Bio:
Vasilios Mavroudis is a Doctoral Researcher in the Information Security Group at University College London, where he studies the security and privacy aspects of digital ecosystems with a focus on emerging technologies and previously unknown attack vectors. In cooperation with industrial partners, he recently released a prototype of a high-assurance cryptographic hardware architecture that maintains its security properties even in the presence of malicious hardware components. Moreover, his study on ultrasound tracking received wide-spread attention and is considered the seminal work on the security of that ecosystem.