Leakage-Resilient Zero Knowledge and its Applications
Speaker: Abhishek Jain , UCLA
Date: April 22 2011
Time: 10:30AM to 12:00PM
Location: 32-G449 Patil/Kiva
Host: Shafi Goldwasser, CSAIL, MIT
Contact: Be Blackburn , 3-6098, imbe@mit.edu
Relevant URL: We initiate a study of zero knowledge proof systems in the presence
of side-channel attacks. Specifically, we consider a setting
where a cheating verifier is allowed to obtain arbitrary
bounded leakage on the entire state (including the witness and
the random coins) of the prover during the entire protocol
execution. We formalize a meaningful definition of
leakage-resilient zero knowledge (LR-ZK) proof system, that
intuitively guarantees that "the protocol does not yield
anything beyond the validity of the statement and the leakage
obtained by the verifier."
We give a construction of LR-ZK interactive proof system
based on general assumptions. To the best of our knowledge,
this is the first instance of a cryptographic protocol where
the adversary is allowed to perform leakage attacks during
the protocol execution (in contrast, prior work only focused
on leakage-resilient primitives such as encryption, or
leakage-resilient devices, or leakage prior to the protocol
execution). Next, we give an LR-NIZK argument system based
on standard assumptions.
Finally, we
demonstrate the usefulness of our notions by giving two
concrete applications: (1) We show how to do UC secure
computation in the "leaky token model" (i.e., where an
adversary in possession of a token can obtain arbitrary
bounded leakage on the entire state of the token) based on
standard assumptions. (2) Next, we give a new construction
of fully leakage-resilient signatures in the bounded leakage
model (as well as the continual leakage model) based on
standard assumptions. In contrast to the recent
constructions of fully leakage resilient signatures, our
scheme is also secure in the noisy leakage model.
Joint work with Sanjam Garg and Amit Sahai.
See other events that are part of CIS Seminars 2010/2011
See other events happening in April 2011
