open-standards/sandbox/sandbox-rs/crates/sandbox-tee/examples/attested_efficiency.rs

//! End-to-end: a completed coding task's measured energy is attested inside a TEE,
//! committed into an `efficiency/1` receipt, and then independently re-verified
//! from scratch — deriving the honest trust level, never asserting it. This is the
//! whole frontier composed in one runnable flow.
//!
//!   cargo run -p sandbox-tee --example attested_efficiency

use ed25519_dalek::SigningKey;
use jcp_efficiency::{verify as verify_efficiency, Efficiency};
use jcp_schema::{ContentId, Energy};
use sandbox_tee::energy::{
    attest_energy, verify_attested_energy, AttestTrust, CounterClass, EnergyStatement,
};
use sandbox_tee::provider::LocalSnpProvider;
use sandbox_tee::Grounding;

fn main() {
    // ── 1. A coding task completed: 900 accepted tokens over a 2 s window, and the
    //       on-device meter read 117 mJ. (A RAPL figure — a real sensor reading,
    //       but platform-self-reported.)
    let energy_uj: u64 = 117_000;
    let window_ns: u64 = 2_000_000_000;
    let tokens_out: u64 = 900;

    // ── 2. A verifier issues a fresh nonce; we attest the reading inside a TEE. The
    //       LocalSnpProvider mints a real ECDSA-P384 report — software-grounded.
    let nonce = [0x5au8; 32];
    let measurement = [0x11u8; 48];
    let provider = LocalSnpProvider::new(measurement, 7);
    let statement = EnergyStatement {
        counter: CounterClass::Rapl,
        energy_uj,
        window_ns,
        nonce,
    };
    let attested = attest_energy(statement, &provider).expect("attest the reading");

    // ── 3. Seal the efficiency/1 receipt, committing to the attestation by content id.
    let sk = SigningKey::from_bytes(&[0xefu8; 32]);
    let steward = "did:jcp:attested-efficiency-demo";
    let eff = Efficiency {
        task: "fix-auth-bug".into(),
        completed: true,
        verdict: "tests-pass".into(),
        tokens_in: tokens_out * 8,
        tokens_out,
        energy: Energy::modeled(energy_uj),
        wall_ns: window_ns,
        value_uusd: Some(5_000_000),
        energy_attestation: None,
    }
    .with_energy_attestation(&attested.report);
    let envelope = eff.seal(0, &ContentId([0u8; 32]), &sk, steward);

    println!(
        "sealed efficiency/1 for '{}' — {} µJ over {} accepted tokens\n",
        eff.task, energy_uj, tokens_out
    );

    // ── 4. A relying party runs the COMPOSED verification, from scratch:
    // (a) the receipt verifies under the steward key.
    let rec = verify_efficiency(&envelope, steward, &sk.verifying_key().to_bytes())
        .expect("efficiency/1 verifies");
    // (b) its commitment resolves to the attestation we hold.
    let commitment = rec
        .energy_attestation
        .as_deref()
        .expect("receipt carries an attestation commitment");
    let resolved = ContentId::of_bytes(&attested.report).to_hex();
    assert_eq!(commitment, resolved, "commitment must match the attestation");
    // (c) the attestation verifies — deriving the honest trust level from evidence.
    let trust = verify_attested_energy(
        &attested,
        measurement,
        &nonce,
        &provider.vcek(),
        Grounding::Software,
    )
    .expect("attestation verifies");
    // (d) the attested joules equal the sealed joules.
    assert_eq!(
        attested.statement.energy_uj, rec.energy_uj,
        "attested energy must match the receipt"
    );

    println!("composed verification ✓");
    println!("  receipt          : verified under the steward key");
    println!("  commitment       : matches the attestation ({}…)", &commitment[..16]);
    println!(
        "  attested energy  : {} µJ  ==  receipt energy {} µJ",
        attested.statement.energy_uj, rec.energy_uj
    );
    println!("  nonce            : fresh (matches the issued challenge)");
    println!("  efficiency       : {} µJ / accepted token", rec.uj_per_accepted_token);
    println!("  TRUST LEVEL      : {trust:?}");
    println!();

    // ── 5. The honesty the whole exercise turns on.
    assert_eq!(trust, AttestTrust::IntegrityAttested);
    println!(
        "This is IntegrityAttested, not PhysicallyRooted: a software-grounded report\n\
         over a platform-self-reported counter (RAPL) attests an honest *relay* inside\n\
         a measured environment — not a reading rooted independently of the platform.\n\
         (Not a claim that RAPL is inaccurate: it is a real sensor reading; nothing\n\
         binds it to the sensor.) An independent root needs a dedicated sensor signed\n\
         at the source (a shunt) on confidential hardware — derived here, never asserted."
    );

    // Prove tampering is caught: rewrite the sealed energy figure downstream.
    let mut forged = attested.clone();
    forged.statement.energy_uj = 1;
    assert!(
        verify_attested_energy(&forged, measurement, &nonce, &provider.vcek(), Grounding::Software)
            .is_err(),
        "a tampered energy figure must fail attestation verification"
    );
    println!("\n(a tampered joule figure fails attestation verification — checked.)");
}