COMA: Communication and Obfuscation Management Architecture


Kimia Zamiri Azar, Farnoud Farahmand, Hadi Mardani Kamali, Shervin Roshanisefat, and Houman Homayoun, George Mason University; William Diehl, Virginia Tech; Kris Gaj and Avesta Sasan, George Mason University


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 attack on key management architecture, and providing two new means of the secure communication to/from an COMA-secured untrusted chip.

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@inproceedings {242034,
author = {Kimia Zamiri Azar and Farnoud Farahmand and Hadi Mardani Kamali and Shervin Roshanisefat and Houman Homayoun and William Diehl and Kris Gaj and Avesta Sasan},
title = {{COMA}: Communication and Obfuscation Management Architecture},
booktitle = {22nd International Symposium on Research in Attacks, Intrusions and Defenses (RAID 2019)},
year = {2019},
isbn = {978-1-939133-07-6},
address = {Chaoyang District, Beijing},
pages = {181--195},
url = {},
publisher = {USENIX Association},
month = sep