Initial Commit

packages/security-stack/crypto/crypto-sodium/src/primitives/ristretto255/ristretto255.test.ts

@@ -0,0 +1,82 @@
+import { beforeAll, describe, expect, it } from "@suaveplan/testing/runner";
+import { sodiumReady } from "../../init/init.js";
+import { ristretto255 } from "./ristretto255.js";
+
+describe("ristretto255", () => {
+    beforeAll(async () => {
+        await sodiumReady();
+    }, 30_000);
+
+    it("random() produces 32-byte group element", {
+        timeout: 30_000,
+    }, async () => {
+        const p = await ristretto255.random();
+        expect(p.length).toBe(32);
+    });
+
+    it("random() produces different elements each call", {
+        timeout: 30_000,
+    }, async () => {
+        const p = await ristretto255.random();
+        const q = await ristretto255.random();
+        expect(p).not.toEqual(q);
+    });
+
+    it("fromHash() maps 64 bytes to a group element", {
+        timeout: 30_000,
+    }, async () => {
+        const hash = new Uint8Array(64).fill(0x42);
+        const point = await ristretto255.fromHash(hash);
+        expect(point.length).toBe(32);
+    });
+
+    it("add(p, q) is commutative: add(p,q) == add(q,p)", {
+        timeout: 30_000,
+    }, async () => {
+        const p = await ristretto255.random();
+        const q = await ristretto255.random();
+        const pq = await ristretto255.add(p, q);
+        const qp = await ristretto255.add(q, p);
+        expect(pq).toEqual(qp);
+    });
+
+    it("add then sub is identity", { timeout: 30_000 }, async () => {
+        const p = await ristretto255.random();
+        const q = await ristretto255.random();
+        const sum = await ristretto255.add(p, q);
+        const back = await ristretto255.sub(sum, q);
+        expect(back).toEqual(p);
+    });
+
+    it("mul scalar*point produces a 32-byte element", {
+        timeout: 30_000,
+    }, async () => {
+        const p = await ristretto255.random();
+        // Use a small non-zero scalar
+        const scalar = new Uint8Array(32);
+        scalar[0] = 2;
+        const result = await ristretto255.mul(scalar, p);
+        expect(result.length).toBe(32);
+    });
+
+    it("toBytes returns a copy of the point", { timeout: 30_000 }, async () => {
+        const p = await ristretto255.random();
+        const bytes = await ristretto255.toBytes(p);
+        expect(bytes).toEqual(p);
+        // Mutation of result doesn't affect original
+        bytes[0] ^= 0xff;
+        expect(bytes).not.toEqual(p);
+    });
+
+    it("fromBytes accepts a valid point", { timeout: 30_000 }, async () => {
+        const p = await ristretto255.random();
+        const back = await ristretto255.fromBytes(p);
+        expect(back).toEqual(p);
+    });
+
+    it("fromBytes throws for invalid point", { timeout: 30_000 }, async () => {
+        // High-bit patterns outside the ristretto255 field are not valid points
+        const bad = new Uint8Array(32).fill(0xff);
+        await expect(ristretto255.fromBytes(bad)).rejects.toThrow(RangeError);
+    });
+});