Paper 2021/034
Circuit-PSI with Linear Complexity via Relaxed Batch OPPRF
Nishanth Chandran and Divya Gupta and Akash Shah
Abstract
$P_0$ and $P_1$ hold sets $\mathsf{S}_{0}$ and $\mathsf{S}_{1}$ respectively and wish to securely compute a function $f$ over the set $\mathsf{S}_{0} \cap \mathsf{S}_{1}$ (e.g., cardinality, sum over associated attributes, or threshold intersection). Following a long line of work, Pinkas et al. ($\mathsf{PSTY}$, Eurocrypt 2019) showed how to construct a concretely efficient Circuit-PSI protocol with linear communication complexity. However, their protocol requires super-linear computation. In this work, we construct concretely efficient Circuit-PSI protocols with linear computational and communication cost. Further, our protocols are more performant than the state-of-the-art, $\mathsf{PSTY}$ -- we are $\approx 2.3\times$ more communication efficient and are up to $2.8\times$ faster. We obtain our improvements through a new primitive called Relaxed Batch Oblivious Programmable Pseudorandom Functions ($\mathsf{RBOPPRF}$) that can be seen as a strict generalization of Batch $\mathsf{OPPRF}$s that were used in $\mathsf{PSTY}$. We believe that this primitive could be of independent interest.
Metadata
- Available format(s)
- Category
- Cryptographic protocols
- Publication info
- Preprint.
- Keywords
- Private Set IntersectionSecure Computation
- Contact author(s)
- nichandr @ microsoft com,divya gupta @ microsoft com,t-akshah @ microsoft com
- History
- 2022-04-06: last of 2 revisions
- 2021-01-12: received
- See all versions
- Short URL
- https://ia.cr/2021/034
- License
-
CC BY