Module consensus 

Ringtail Consensus Integration for ZAP

Implements threshold lattice-based signing compatible with the Ringtail protocol. Uses ML-DSA (FIPS 204) lattice cryptography for post-quantum security.

Protocol Overview

Ringtail is a threshold signature scheme based on lattice cryptography:

• Round 1: Parties generate commitment matrices D and MACs
• Round 2: Verify MACs, compute response shares z_i
• Finalize: Combiner aggregates shares into final signature (c, z, Delta)

Example

use zap::consensus::{RingtailConsensus, AgentConsensus};

// Create threshold signing party
let mut party = RingtailConsensus::new(0, 3, 2); // party 0 of 3, threshold 2
party.connect_peers(vec!["peer1:9999".into(), "peer2:9999".into()]).await?;

// Sign a message
let round1 = party.sign_round1(b"message").await?;
// ... exchange with other parties ...
let round2 = party.sign_round2(vec![round1, peer1_r1, peer2_r1]).await?;
// ... combiner finalizes ...
let sig = party.finalize(vec![round2, peer1_r2, peer2_r2]).await?;

Structs

AgentConsensus

Simplified agent consensus for response voting

PeerConnection

Connection to a peer party

Poly

Ring polynomial represented as coefficients mod Q

QueryState

Query state for agent consensus voting

RingtailConsensus

Ringtail-compatible consensus for ZAP agents

RingtailSignature

Ringtail threshold signature

Round1Output

Round 1 output from a party

Round2Output

Round 2 output from a party

Constants

COMBINER_ID

Combiner party ID

DBAR

Commitment dimension Dbar

DEFAULT_PARTIES

Default number of parties

DEFAULT_THRESHOLD

Default threshold for 3-of-3 signing

KAPPA

Challenge weight (Hamming weight of challenge polynomial)

KEY_SIZE

Key size in bytes (256 bits)

LOG_N

Log of ring dimension

M

Matrix dimension M (rows)

N

Matrix dimension N (columns)

NU

Rounding parameter Nu

PHI

Ring dimension (2^LOG_N)

Q

Prime modulus Q (48-bit NTT-friendly)

XI

Rounding parameter Xi

Type Aliases

PolyMatrix

Matrix of ring polynomials

PolyVector

Vector of ring polynomials