Combining Zero-Knowledge Proofs on RDF graphs (W3C Verifiable Credentials)

based on the cryptographic work of Lovesh Harchandani

We use dock/crypto as a submodule for proof of knowledge of BBS+ signature, LegoGroth16 range proof and Accumulator non-membership.

Repository Structure

• benches/ a sample benchmark of of the MT-based and schema-based approach.
• data/ the Verifiable Credential (VC) and Verifiable Presentation (VP) that are being generated when running the examples.
• dock/crypto/ the submodule that provides the cryptographic functions.
• src/ source code.
  • bin/ examples that you can execute.
  • poc/ proof of concept implementations of the different procedures (issue,prove,verify) in two versions: model theory (MT)-based (no suffix) and schema-based ("_schema" suffix).
  • rdf4zkp functions for encoding RDF to field representations.
  • zkp4rdf functions for transforming zkp related variables and values to RDF.
• vocab/ the vocabulary used to describe the proofs.
  • zkp-o.ttl general terms for zero-knowledge proofs.
  • zkp-o-spok.ttl terms for Schnorr proofs of knowledge (of discrete log).
  • zkp-o-bbs.ttl terms for BBS+ proof of knowledge of signature.
  • zkp-o-lg16.ttl terms for LegoGroth16 proof of numeric bounds.
  • zkp-o-uacc.ttl terms for Univeral Accumulator proof of set (non-)membership.

Run it yourself

# set up the repo
git clone <repo-url>
cd <repo>
git submodule update --init --recursive

# using RDF model theory (MT)-based transformation
cargo run --bin issuer
cargo run --bin prover
cargo run --bin verifier

# using schema-based transformation
cargo run --bin issuer_schema
cargo run --bin prover_schema
cargo run --bin verifier_schema

# benchmark the performance difference
cargo bench

We used the rust compiler rustc 1.66.0 (69f9c33d7 2022-12-12). Just in case that is relevant at some point in time.

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This is a proof of concept, not a library.