Attestation

Attestation proves a node’s hardware/software integrity before it joins the cluster. It is optional (A5): dev/small deployments work without hardware attestation.

Providers

Software attestation (dev/test)

SoftwareAttestation generates a SHA-256 hash of the running binary and OS information, bound to a nonce:

quote = SHA-256(binary_hash || os || arch || nonce)
signature = quote  (self-signed — intentionally weak)

Weakness: only proves the binary hasn’t been modified at rest. Does not prove the platform is trustworthy. A compromised system can forge a quote.

Use case: dev, testing, CI. Clearly marked as dev-only.

TPM attestation (production, feature-gated)

TpmAttestation uses TPM 2.0 to produce a cryptographically signed quote of the platform’s boot state:

• Uses the TPM’s Attestation Identity Key (AIK)
• Quote includes the nonce (prevents replay)
• Signature is verifiable against the AIK public key
• Requires a TPM 2.0 chip and the tss feature

Use case: production, high-security environments.

Verification

#![allow(unused)]
fn main() {
pub fn verify_software_attestation(
    result: &AttestationResult,
    expected_nonce: &[u8],
) -> Result<(), SecurityError>
}

Checks:

1. The quote matches the expected value (binary_hash + os + arch + nonce)
2. The signature matches the quote (self-signed for software)
3. The nonce matches (prevents replay)

Tampering with any field after attestation causes verification to fail.

Attestation result

#![allow(unused)]
fn main() {
pub struct AttestationResult {
    pub node_id: NodeId,
    pub binary_hash: [u8; 32],
    pub os: String,
    pub arch: String,
    pub quote: Vec<u8>,
    pub signature: Vec<u8>,
    pub provider: AttestationProvider,
}
}

The provider field indicates whether software or TPM attestation was used, allowing the enrollment ceremony to reject weak attestation in production environments.