Paper 2022/370
Efficient NIZKs from LWE via Polynomial Reconstruction and ``MPC in the Head"
Riddhi Ghosal and Paul Lou and Amit Sahai
Abstract
All existing methods of building non-interactive zero-knowledge (NIZK) arguments for $\mathsf{NP}$ from the Learning With Errors (LWE) assumption have relied on instantiating the Fiat-Shamir paradigm on a parallel repetition of an underlying honest-verifier zero knowledge (HVZK) $\Sigma$ protocol, via an appropriately built correlation-intractable (CI) hash function from LWE. This technique has inherent efficiency losses that arise from parallel repetition. In this work, we build the first NIZK argument for $\mathsf{NP}$ from the LWE assumption that does not rely on parallel repetition. Instead, we show how to make use of the more efficient ``MPC in the Head'' technique for building an underlying honest-verifier protocol upon which to apply the Fiat-Shamir paradigm. The key to making this possible is a new construction of CI hash functions from LWE, using efficient algorithms for polynomial reconstruction as the main technical tool. We stress that our work provides a new and more efficient ``base construction'' for building LWE-based NIZK arguments for $\mathsf{NP}$. Our protocol can be the building block around which other efficiency-focused bootstrapping techniques can be applied, such as the bootstrapping technique of Gentry et al. (Journal of Cryptology 2015).
Metadata
- Available format(s)
- Category
- Cryptographic protocols
- Publication info
- Preprint.
- Contact author(s)
- riddhi @ cs ucla edu,pslou @ cs ucla edu,sahai @ cs ucla edu
- History
- 2022-06-01: revised
- 2022-03-22: received
- See all versions
- Short URL
- https://ia.cr/2022/370
- License
-
CC BY