CryptoDB
Bingsheng Zhang
Affiliation: National and Kapodistrian University of Athens
Publications
Year
Venue
Title
2020
ASIACRYPT
Crowd Verifiable Zero-Knowledge and End-to-end Verifiable Multiparty Computation
📺
Abstract
Auditing a secure multiparty computation (MPC) protocol
entails the validation of the protocol transcript
by a third party that is otherwise untrusted.
In this work we introduce the concept of end-to-end verifiable
MPC (VMPC), that requires the validation to provide a correctness
guarantee even in the setting that all servers, trusted setup
primitives and all the client systems utilized by the input-providing
users of the MPC protocol are subverted by an adversary.
To instantiate VMPC, we introduce a new concept in the setting of
zero-knowlegde protocols that we term crowd verifiable zero-knowledge
(CVZK). A CVZK protocol enables a prover to convince a set of verifiers
about a certain statement, even though each one individually contributes
a small amount of entropy for verification and some of them are adversarially
controlled. Given CVZK, we present a VMPC protocol that
is based on discrete-logarithm related assumptions.
At the high level of adversity that VMPC is meant to withstand,
it is infeasible to ensure perfect correctness,
thus we investigate the classes of functions and
verifiability relations that are feasible in our framework, and
present a number of possible applications the underlying
functions of which can be implemented via VMPC.
Coauthors
- Foteini Baldimtsi (2)
- Prastudy Fauzi (1)
- Aggelos Kiayias (5)
- Helger Lipmaa (1)
- Thomas Zacharias (5)