Rivellum uses CRYSTALS-Dilithium3 (ML-DSA-65, FIPS 204) as its sole signature scheme. All accounts are post-quantum secure by default.

Key Scheme

There is no hybrid mode or classical fallback. Every signature on Rivellum is post-quantum.

Single-Key Accounts

The default account type uses a single Dilithium keypair:

AccountAuth {
    scheme: KeyScheme::Dilithium,
    public_keys: vec![dilithium_pubkey],
    threshold: None,
    session_keys: vec![],
}

Multi-Signature Accounts

Multi-sig accounts require M-of-N Dilithium signatures:

AccountAuth {
    scheme: KeyScheme::DilithiumMultiSig { threshold: 2 },
    public_keys: vec![key_a, key_b, key_c],  // 2-of-3
    threshold: Some(2),
    session_keys: vec![],
}

• Threshold range: 1 to N (where N = number of keys)
• All keys must be valid Dilithium public keys (1,952 bytes each)
• Intents require at least threshold valid signatures

Session Keys

Session keys provide delegated signing authority with fine-grained policies:

SessionKey {
    public_key: PublicKey::Dilithium(key_bytes),
    policy: SessionKeyPolicy {
        allowed_contracts: vec![contract_addr],  // restrict to specific contracts
        max_fee_per_intent: 1_000_000,           // fee cap per intent
        expiration_ms: 1700000000000,            // absolute expiry timestamp
        max_calls: 100,                          // total invocations allowed
    },
    created_at_ms: 1699000000000,
    calls_used: 0,
    revoked: false,
}

Session Key Operations

Session keys are checked against their policy on every use:

• Must not be revoked
• Must not exceed max_calls
• Must not be past expiration_ms
• Target contract must be in allowed_contracts
• Fee must not exceed max_fee_per_intent

SDK Usage

The TypeScript AI SDK (@rivellum/ai-sdk) exposes RivellumAgent for AI-economy operations. Account authentication configuration (key scheme, session keys) is not wrapped by the SDK; query it directly via the HTTP API:

// Query account nonce
const nonce = await fetch(
  `https://rpc.rivellum.network/v1/nonce/${address}`
);
const data = await nonce.json();
console.log(`Nonce: ${data.nonce}`);

// Query balance  
const balance = await fetch(
  `https://rpc.rivellum.network/v1/balance/${address}`
);
const balanceData = await balance.json();
console.log(`Balance: ${balanceData.balance}`);

Or with curl:

curl https://rpc.rivellum.network/v1/nonce/0x1234.../
curl https://rpc.rivellum.network/v1/balance/0x1234.../

Security Considerations

• Dilithium3 is a NIST-standardized post-quantum signature scheme resistant to attacks from both classical and quantum computers
• Key sizes are larger than classical schemes (Ed25519), but security guarantees are significantly stronger
• Session keys limit blast radius: even if compromised, damage is bounded by policy constraints
• Multi-sig adds organizational security without sacrificing post-quantum properties