ARM OpenVM Noir: Transfer Auth Circuit

This repository contains a Noir-based implementation of the Transfer Authorization logic for the Anoma Resource Machine (ARM).

This code is almost a translation of the Rust-based OpenVM implementation found in the official Anoma repository: arm-openvm/arm_core/src/transfer_auth.rs.

Performance Benchmarks

By writing this logic directly as a Noir circuit and proving it with Barretenberg, we bypass the overhead of the zkVM instruction set architecture.

Hardware Specifications:

• CPU: AMD Ryzen™ 9 6900HX (20 MB cache, 8 cores, up to 4.90 GHz)

Proving Times (CPU):

• Noir (This Repo): 1.968s (Note: This excludes 1527 ms for computing the proving key).
• OpenVM: 51.985s

This represents a ~26.4x speedup in proving time.

Prerequisites

To compile, execute, and prove this circuit, you will need the Noir toolchain (nargo) and the Barretenberg prover CLI (bb).

1. Install Noirup to get nargo:

   curl -L https://raw.githubusercontent.com/noir-lang/noirup/main/install | bash
   noirup

2. Install bbup to get the Barretenberg CLI (bb):

   curl -L https://raw.githubusercontent.com/AztecProtocol/aztec-packages/refs/heads/next/barretenberg/bbup/install | bash
   bbup

Testing

To run the inline tests (including the ephemeral wrap, ephemeral unwrap, persistent consume, and persistent create tests):

nargo test

Compilation and Execution

Before generating proofs, you must compile the circuit into an intermediate representation (ACIR) and execute it to generate the witness.

1. Compile the circuit:

   nargo compile

   This generates ./target/arm_openvm_noir.json.
2. Execute the circuit to generate the witness:

   nargo execute

   This generates the witness file at ./target/arm_openvm_noir.gz.

Proving

We use Barretenberg with the Ultraplonk backend to generate EVM-compatible proofs.

Option 1: Prove and write the Verification Key If this is your first time proving, or if the circuit has changed, you will want to write the verification key (vk) alongside the proof:

bb prove -b ./target/arm_openvm_noir.json -w ./target/arm_openvm_noir.gz -t evm --write_vk -o target

Option 2: Standard Prove If you already have the verification key generated and just need to generate a new proof for a new witness:

bb prove -b ./target/arm_openvm_noir.json -w ./target/arm_openvm_noir.gz -t evm -o target

Both commands will output a proof file in the ./target/ directory.