VIA — Communication-Efficient Single-Server PIR

A pure-Rust implementation of the VIA family · paper: Liu, Wang & Zhang (2025)

Private Information Retrieval lets a client fetch the i-th record of a server-held database while keeping i hidden from the server, from a single server, with no non-collusion assumption. VIA does this with a logarithmic-depth DMux tree for query expansion and (in VIA-C) a low-noise LWE→RLWE conversion for query compression.

Intro to VIA

The scheme as a chain of forced moves, with examples.

Abstract Architecture

A map of VIA's components, how they stack, and how a query flows through them.

Rust Implementation

The via-rs codebase as built: the crate map, the primitive→paper cross-reference, and build/test status.

Parameters

Analysis of the security and correctness of VIA's parameters in the paper (broken) and in the code (fixed, adding overhead).

Audit

A severity-ranked correctness/security audit of VIA-C and VIA-B, each finding adversarially re-validated against the paper and the pinned code.

Scope: VIA-C and VIA-B are implemented (VIA-B behind the via-b cargo feature); plain VIA is not yet implemented. See the repository and its README for build & test instructions.