Feature-complete for implementing real crypto

examples/dilithium.rs

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+//! Example of simplified Dilithium with q=8380417
+
+use gwrizienn::{
+	matrix::Matrix,
+	ntt::{Ntt, NttInv},
+	ring::Ring,
+	vector::Vector,
+	*,
+};
+
+// Implement Zq
+ring!(Zq, u32, u64, i64, 8380417);
+
+// Implement Rq = Zq/(x^256+1)
+// zeta=1753 is the first 512-th root of unity mod q
+poly!(Rq, 256, Zq, u32, u64, u32, u64, 8380417, 1753);
+
+fn high_bits<const N: usize>(mut v: Vector<Rq, N>) -> Vector<Rq, N> {
+	for vi in v.0.iter_mut() {
+		for vij in vi.0.iter_mut() {
+			vij.0 -= vij.0 % 190464;
+		}
+	}
+	v
+}
+
+fn main() {
+	let mut rng = rand::thread_rng();
+	let uniform = Zq::uniform();
+	let ball_c = Zq::uniform_ball(1);
+	let ball_s = Zq::uniform_ball(2);
+	let ball_y = Zq::uniform_ball(131071);
+
+	// generate secret key
+	let a = Matrix::<Rq, 4, 4>::random(uniform, &mut rng);
+	let s1 = Vector::<Rq, 4>::random(ball_s, &mut rng);
+	let s2 = Vector::<Rq, 4>::random(ball_s, &mut rng);
+	// random value for signing
+	let y = Vector::<Rq, 4>::random(ball_y, &mut rng);
+	// challenge
+	let c = Rq::random(ball_c, &mut rng);
+
+	// use NTT for fast multiplication
+	let a = a.ntt();
+	let s1 = s1.ntt();
+	let s2 = s2.ntt();
+	let y = y.ntt();
+	let c = c.ntt();
+
+	// generate public key
+	let t = &a * &s1 + s2;
+	// commitment
+	let w = &a * &y;
+	// proof
+	let z = y + s1 * &c;
+
+	// verify
+	assert_eq!(
+		high_bits((&a * &z - t * &c).ntt_inv()),
+		high_bits(w.ntt_inv())
+	);
+
+	// let uniform = Zq::uniform();
+	// let ball_c = Zq::uniform_ball(1);
+	// let ball_s = Zq::uniform_ball(2);
+	// let ball_y = Zq::uniform_ball(131071);
+	//
+	// let a = Matrix::<Rq, 4, 4>::random(uniform, &mut rng).ntt();
+	// let s1 = Vector::<Rq, 4>::random(ball_s, &mut rng).ntt();
+	// let s2 = Vector::<Rq, 4>::random(ball_s, &mut rng).ntt();
+	// let y = Vector::<Rq, 4>::random(ball_y, &mut rng).ntt();
+	// let c = Rq::random(ball_c, &mut rng).ntt();
+	//
+	// let t = &a * &s1 + s2;
+	// let w = &a * &y;
+	// let z = y + s1 * &c;
+}