COMA: Communication and Obfuscation Management Architecture

TL;DR

COMA introduces a secure architecture for obfuscated circuits that eliminates key storage on untrusted chips, employs dynamic key changes, and offers secure communication methods, enhancing security and efficiency.

Contribution

It presents a novel architecture that manages obfuscation keys dynamically and secures communication, reducing area overhead and enabling new security features.

Findings

Reduces area overhead by 14% compared to existing solutions.

Enables unique chip authentication and activation as a service.

Provides two secure communication mechanisms with different performance-security trade-offs.

Abstract

In this paper, we introduce a novel Communication and Obfuscation Management Architecture (COMA) to handle the storage of the obfuscation key and to secure the communication to/from untrusted yet obfuscated circuits. COMA addresses three challenges related to the obfuscated circuits: First, it removes the need for the storage of the obfuscation unlock key at the untrusted chip. Second, it implements a mechanism by which the key sent for unlocking an obfuscated circuit changes after each activation (even for the same device), transforming the key into a dynamically changing license. Third, it protects the communication to/from the COMA protected device and additionally introduces two novel mechanisms for the exchange of data to/from COMA protected architectures: (1) a highly secure but slow double encryption, which is used for exchange of key and sensitive data (2) a high-performance and low-energy yet leaky encryption, secured by means of frequent key renewal. We demonstrate that compared to state-of-the-art key management architectures, COMA reduces the area overhead by 14%, while allowing additional features including unique chip authentication, enabling activation as a service (for IoT devices), reducing the side channel threats on key management architecture, and providing two new means of secure communication to/from an untrusted chip.