frost/frost-ristretto255/src/tests.rs

use rand::thread_rng;

use crate::*;

mod vectors;

use vectors::*;

/// This is testing that Shamir's secret sharing to compute and arbitrary
/// value is working.
#[test]
fn check_share_generation_ristretto255_sha512() {
    let mut rng = thread_rng();

    let secret = frost::keys::Secret::<Ristretto255Sha512>::random(&mut rng);

    let secret_shares = frost::keys::generate_secret_shares(&secret, 5, 3, rng).unwrap();

    for secret_share in secret_shares.iter() {
        assert_eq!(secret_share.verify(), Ok(()));
    }

    assert_eq!(
        frost::keys::reconstruct_secret::<Ristretto255Sha512>(secret_shares).unwrap(),
        secret
    )
}

#[test]
fn check_sign_with_test_vectors() {
    let (
        group_public,
        key_packages,
        _message,
        message_bytes,
        signer_nonces,
        signer_commitments,
        group_binding_factor_input,
        group_binding_factor,
        signature_shares,
        signature_bytes,
    ) = parse_test_vectors();

    type R = Ristretto255Sha512;

    ////////////////////////////////////////////////////////////////////////////
    // Key generation
    ////////////////////////////////////////////////////////////////////////////

    for key_package in key_packages.values() {
        assert_eq!(
            *key_package.public(),
            frost::keys::Public::from(*key_package.secret_share())
        );
    }

    /////////////////////////////////////////////////////////////////////////////
    // Round 1: generating nonces and signing commitments for each participant
    /////////////////////////////////////////////////////////////////////////////

    for (i, _) in signer_commitments.clone() {
        // compute nonce commitments from nonces
        let nonces = signer_nonces.get(&i).unwrap();
        let nonce_commitments = signer_commitments.get(&i).unwrap();

        assert_eq!(
            &frost::round1::NonceCommitment::from(nonces.hiding()),
            nonce_commitments.hiding()
        );

        assert_eq!(
            &frost::round1::NonceCommitment::from(nonces.binding()),
            nonce_commitments.binding()
        );
    }

    /////////////////////////////////////////////////////////////////////////////
    // Round 2: each participant generates their signature share
    /////////////////////////////////////////////////////////////////////////////

    let signer_commitments_vec = signer_commitments
        .into_iter()
        .map(|(_, signing_commitments)| signing_commitments)
        .collect();

    let signing_package = frost::SigningPackage::new(signer_commitments_vec, message_bytes);

    assert_eq!(signing_package.rho_preimage(), group_binding_factor_input);

    let rho: frost::Rho<R> = (&signing_package).into();

    assert_eq!(rho, group_binding_factor);

    let mut our_signature_shares: Vec<frost::round2::SignatureShare<R>> = Vec::new();

    // Each participant generates their signature share
    for index in signer_nonces.keys() {
        let key_package = &key_packages[index];
        let nonces = &signer_nonces[index];

        // Each participant generates their signature share.
        let signature_share = frost::round2::sign(&signing_package, nonces, key_package).unwrap();

        our_signature_shares.push(signature_share);
    }

    for sig_share in our_signature_shares.clone() {
        assert_eq!(sig_share, signature_shares[sig_share.index()]);
    }

    let signer_pubkeys = key_packages
        .into_iter()
        .map(|(i, key_package)| (i, *key_package.public()))
        .collect();

    let pubkey_package = frost::keys::PublicKeyPackage {
        signer_pubkeys,
        group_public,
    };

    ////////////////////////////////////////////////////////////////////////////
    // Aggregation:  collects the signing shares from all participants,
    // generates the final signature.
    ////////////////////////////////////////////////////////////////////////////

    // Aggregate the FROST signature from test vector sig shares
    let group_signature_result = frost::aggregate(
        &signing_package,
        &signature_shares
            .values()
            .cloned()
            .collect::<Vec<frost::round2::SignatureShare<R>>>(),
        &pubkey_package,
    );

    // Check that the aggregation passed signature share verification and generation
    assert!(group_signature_result.is_ok());

    // Check that the generated signature matches the test vector signature
    let group_signature = group_signature_result.unwrap();
    assert_eq!(group_signature.to_bytes().to_vec(), signature_bytes);

    // Aggregate the FROST signature from our signature shares
    let group_signature_result =
        frost::aggregate(&signing_package, &our_signature_shares, &pubkey_package);

    // Check that the aggregation passed signature share verification and generation
    assert!(group_signature_result.is_ok());

    // Check that the generated signature matches the test vector signature
    let group_signature = group_signature_result.unwrap();
    assert_eq!(group_signature.to_bytes().to_vec(), signature_bytes);
}