Thursday June 6
9:00AM, Aula Mutis
Prof. Srini Devadas (MIT)
Title: Towards Secure High-Performance Computer Architectures
Abstract: Recent work has shown that architectural isolation can be violated through software side channel attacks that exploit microarchitectural performance optimizations such as speculation to leak secrets. While turning off microarchitectural optimizations can preclude some classes of attacks, we argue that performance and security do not have be in conflict, provided processors are designed with security in mind.
We advocate designing processors to support enclaves, which are processes with an associated security policy, and espouse a principled hardware/software co-design approach to eliminating entire attack surfaces relevant to the security policy through microarchitectural isolation, rather than plugging attack-specific privacy leaks. As a case study of this approach, we describe both in-order and speculative processor designs that offer strong provable isolation of software modules running concurrently and sharing resources, even when large parts of the operating system are compromised. Open-source implementations of these processors will allow security properties to be independently verified. Finally, we describe the current limitations of this approach and future opportunities for research.
Bio: Srini Devadas is the Webster Professor of EECS at MIT where he has been on the faculty since 1988. His current research interests are in computer security, computer architecture and applied cryptography. Devadas received the 2015 ACM/IEEE Richard Newton award, the 2017 IEEE W. Wallace McDowell award and the 2018 IEEE Charles A. Desoer award for his research in secure hardware. He is a Fellow of the ACM and IEEE. Devadas is the author of “Programming for the Puzzled” (MIT Press, 2017), a book that builds a bridge between the recreational world of algorithmic puzzles and the pragmatic world of computer programming, teaching readers to program while solving puzzles. He is a MacVicar Faculty Fellow, an Everett Moore Baker and a Bose award recipient, considered MIT’s highest teaching honors.
Friday June 7
9:00 AM, Aula Mutis
Prof. Juan Garay (Texas A&M University)
Title: Foundational Aspects of Blockchain Protocols
Abstract: Decentralized cryptocurrencies such as Bitcoin have ignited much excitement, not only for their novel realization of central bank-free financial instruments, but also as an alternative approach to classical distributed computing problems, such as reaching agreement distributedly in the presence of potentially misbehaving parties, as well as to numerous other applications―contracts, reputation systems, name services, etc. The soundness and security of these applications, however, hinge on the thorough understanding of the fundamental properties of their underlying blockchain data structure, which parties (“miners”) maintain and try to extend by generating proofs of various kinds, “proofs of work” (PoW, aka “cryptographic puzzle”) perhaps being the most interesting ones.
In this talk we formulate such fundamental properties of the blockchain, and show how applications such as consensus and a robust public transaction ledger can be built “on top” of them, assuming the adversary’s hashing power is strictly less than ½. The above properties hold assuming that all parties―honest and adversarial―”wake up” and start computing at the same time, or, alternatively, that they compute on a common random string (the “genesis” block) only made available at the exact time when the protocol execution is to begin. We also address the question of whether such a trusted setup/behavioral assumption is necessary, answering it in the negative by presenting a Bitcoin-like blockchain protocol that is provably secure without trusted setup. A direct consequence of this last construction is that consensus can be solved directly by a blockchain protocol without trusted setup assuming an honest majority (in terms of computational power), in contrast to what is known in the classical distributed computing literature, an apparent contradiction that we also explain.
Most of this talk is based on joint work with Aggelos Kiayias (U. of Edinburgh), Nikos Leonardos (U. of Athens) and Giorgios Panagiotakos (U. of Edinburgh).
Bio: Since Fall ’17, Juan Garay is a full professor at Texas A&M University’s Computer Science & Engineering Department. Previously, after receiving his PhD in Computer Science from Penn State, he was a postdoc at the Weizmann Institute of Science (Israel), and held research positions at the IBM T.J. Watson Research Center, Bell Labs, AT&T Labs–Research, and Yahoo Research. His research interests include both foundational and applied aspects of cryptography and information security. He has published extensively in the areas of cryptography, network security, distributed computing, and algorithms; has been involved in the design, analysis and implementation of a variety of secure systems; and is the recipient of over two dozen patents. Dr. Garay has served on the program committees of numerous conferences and international panels—including co-chairing Crypto 2013 and 2014, the discipline’s premier conference. He is a Fellow of the International Association for Cryptologic Research (IACR).