stealth-address-kit

Uses the arkworks-rs suite of libraries, and utilities from rln

Existing Implementations

1. ark_bn254
2. ark_bls_12_381
3. ark_bls_12_377
4. secp256k1
5. secp256r1

Usage

use stealth_address_kit::{StealthAddressOnCurve};
use ark_bn254::Bn254; // or ark_bls_12_381::Bls12_381 or ark_bls_12_377::Bls12_377, stealth_address_kit::Secp256k1, stealth_address_kit::Secp256r1

fn main() {
    let (spending_key, spending_public_key) = Bn254::random_keypair();
    let (viewing_key, viewing_public_key) = Bn254::random_keypair();

    // generate ephemeral keypair
    let (ephemeral_private_key, ephemeral_public_key) = Bn254::random_keypair();

    let (stealth_commitment, view_tag) = Bn254::generate_stealth_commitment(viewing_public_key, spending_public_key, ephemeral_private_key);

    let stealth_private_key_opt = Bn254::generate_stealth_private_key(ephemeral_public_key, viewing_key, spending_key, view_tag);

    if stealth_private_key_opt.is_none() {
        panic!("View tags did not match");
    }

    let derived_commitment = Bn254::derive_public_key(stealth_private_key_opt.unwrap());
    assert_eq!(derived_commitment, stealth_commitment);
}

Adding a new curve

1. Add the curve to the Cargo.toml file, as a feature
2. Create a new module in the src directory, with the curve name, suffixed by _impl.rs
3. Implement the StealthAddressOnCurve trait for the curve
4. Add the curve to the lib.rs file, in the mod declaration
5. Add the curve to the FFI API, in the ffi.rs file
6. Add the curve to the README
7. Add the curve to the nightly release workflow

Building and Testing

1. Building cargo build --release --features <bn254/bls12_381/bls12_377/secp256k1/secp256r1>

2. Testing cargo test --release --features <bn254/bls12_381/bls12_377/secp256k1/secp256r1>

FFI Api

The exposed FFI API supports all curves, prefixed by the curve name. Ensure that the correct feature is enabled when building the library.

Precompiled Libraries

Check out the nightly releases.

Attribution

• The original circuits for rln are located here, by the PSE group
• Inspired by the erc-5564 eip and the poc by Nerolation.