Encrypt theFuture.

// VRIL-KEM KeyGen — Post-Quantum Key Encapsulation
// Security: 384-bit quantum / 256-bit classical
// MLWE parameters: n=4096, q=12289, k=7, η=3

pub struct VrilKemParams {
    pub const N: usize = 4096,     // ring dimension
    pub const Q: u32   = 12289,    // NTT-friendly prime
    pub const K: usize = 7,         // module rank
    pub const ETA: u8 = 3,          // CBD noise parameter
}

pub fn vril_kem_keypair() -> Result<KeyPair> {
    let mut rng = VrilSecureRng::new();
    // 1. Sample A matrix (uniform random, NTT domain)
    let a = PolyMatrix::sample_uniform(&rng, 7)?;
    // 2. HI-Gaussian secret + error (7-layer Fibonacci-weighted)
    let s = PolyVec::sample_hi_gaussian(&rng, 3)?;
    let e = PolyVec::sample_hi_gaussian(&rng, 3)?;
    // 3. Compute public key: b = A·s + e
    let b = a.ntt_mul(&s).add(&e);
    // 4. Apply 7-iteration CVKDF to secret key
    let sk_omega = s.cvkdf_apply();  // Ω = f^7(sk)
    Ok(KeyPair { pk: (a, b), sk: sk_omega })
}

// CVKDF: 7-layer Fibonacci geometric compression
// Depths: [14,9,5,3,2,1,1] | Weights: [1,1,2,3,5,8,13]
fn cvkdf_apply(&self) -> PolyVec {
    let fib   = [1,1,2,3,5,8,13];
    let depth = [14,9,5,3,2,1,1];
    let mut r = self.clone();
    for i in 0..7 { r = r.compress_inward(depth[i], fib[i]); }
    r
}