bls wasm context and private key converted to wasm implementation

package.json

@@ -41,6 +41,7 @@
     "@chainsafe/eth2.0-types": "^0.1.0",
     "@chainsafe/milagro-crypto-js": "0.1.3",
     "assert": "^1.4.1",
+    "bls-wasm": "^0.2.7",
     "js-sha256": "^0.9.0",
     "secure-random": "^1.1.1"
   },

src/context.ts

@@ -0,0 +1,21 @@
+// eslint-disable-next-line import/no-extraneous-dependencies
+import blsWasmWrapper from "@chainsafe/eth2-bls-wasm";
+
+let blsWrapper: typeof blsWasmWrapper | null = null;
+
+export async function init(): Promise<typeof blsWasmWrapper> {
+  await blsWasmWrapper.init();
+  blsWrapper = blsWasmWrapper;
+  return blsWrapper;
+}
+
+export function destroy(): void {
+  blsWrapper = null;
+}
+
+export function getContext(): typeof blsWasmWrapper{
+  if(blsWrapper) {
+    return blsWrapper;
+  }
+  throw new Error("BLS not initialized");
+}

src/privateKey.ts

@@ -1,63 +1,56 @@
-import {BIG} from "@chainsafe/milagro-crypto-js/src/big";
-import {FP_POINT_LENGTH, SECRET_KEY_LENGTH} from "./constants";
+import {SECRET_KEY_LENGTH} from "./constants";
 import assert from "assert";
-import ctx from "./ctx";
-import {padLeft} from "./helpers/utils";
-import {G2point} from "./helpers/g2point";
-import * as random from "secure-random";
-import {BLSSecretKey, Hash, Domain} from "@chainsafe/eth2.0-types";
+import {BLSSecretKey, Domain, Hash} from "@chainsafe/eth2.0-types";
+import {SecretKeyType, SignatureType} from "@chainsafe/eth2-bls-wasm";
+import {getContext} from "./context";
 
 export class PrivateKey {
 
-  private value: BIG;
+  private value: SecretKeyType;
 
-  public constructor(value: BIG) {
+  protected constructor(value: SecretKeyType) {
     this.value = value;
   }
 
   public static fromBytes(bytes: Uint8Array): PrivateKey {
     assert(bytes.length === SECRET_KEY_LENGTH, "Private key should have 32 bytes");
-    const value = Buffer.from(bytes);
-    return new PrivateKey(
-      ctx.BIG.frombytearray(
-        padLeft(
-          value,
-          48
-        ),
-        0
-      )
-    );
+    const context = getContext();
+    const secretKey = new context.SecretKey();
+    secretKey.deserialize(Buffer.from(bytes));
+    return new PrivateKey(secretKey);
   }
 
   public static fromHexString(value: string): PrivateKey {
-    return PrivateKey.fromBytes(
-      Buffer.from(value.replace("0x", ""), "hex")
-    );
+    value = value.replace("0x", "");
+    assert(value.length === SECRET_KEY_LENGTH * 2, "secret key must have 32 bytes");
+    const context = getContext();
+    return new PrivateKey(context.deserializeHexStrToSecretKey(value));
   }
 
   public static random(): PrivateKey {
-    return PrivateKey.fromBytes(random.randomBuffer(SECRET_KEY_LENGTH));
+    const context = getContext();
+    const secretKey = new context.SecretKey();
+    secretKey.setByCSPRNG();
+    return new PrivateKey(secretKey);
   }
 
-  public getValue(): BIG {
+  public getValue(): SecretKeyType {
     return this.value;
   }
 
-  public sign(message: G2point): G2point {
-    return message.mul(this.value);
+  public sign(message: Uint8Array): SignatureType {
+    return this.value.sign(message);
   }
 
-  public signMessage(message: Hash, domain: Domain): G2point {
-    return G2point.hashToG2(message, domain).mul(this.value);
+  public signMessage(message: Hash, domain: Domain): SignatureType {
+    return this.value.signHashWithDomain(Buffer.concat([message, domain]));
   }
 
   public toBytes(): BLSSecretKey {
-    const buffer = Buffer.alloc(FP_POINT_LENGTH, 0);
-    this.value.tobytearray(buffer, 0);
-    return buffer.slice(FP_POINT_LENGTH - SECRET_KEY_LENGTH);
+    return Buffer.from(this.value.serialize());
   }
 
   public toHexString(): string {
-    return `0x${this.toBytes().toString("hex")}`;
+    return `0x${this.value.serializeToHexStr()}`;
   }
 }

test/unit/context.test.ts

@@ -0,0 +1,20 @@
+import {init, getContext, destroy} from "../../src/context";
+import {expect} from "chai";
+
+describe("bls wasm constext", function () {
+
+  afterEach(() => {
+    destroy();
+  });
+
+  it("initializes and works", async function () {
+    await init();
+    expect(getContext().getCurveOrder())
+      .to.be.equal("52435875175126190479447740508185965837690552500527637822603658699938581184513");
+  });
+
+  it("throws if context not initialized", async function () {
+    expect(() => getContext().getCurveOrder()).to.throw();
+  });
+
+});

test/unit/privateKey.test.ts

@@ -1,22 +1,40 @@
 import {PrivateKey} from "../../src/privateKey";
 import {expect} from "chai";
 import {SECRET_KEY_LENGTH} from "../../src/constants";
+import {destroy, init} from "../../src/context";
 
-describe('privateKey', function() {
+describe("privateKey", function() {
 
-    it('should generate random private key', function () {
-        const privateKey1 = PrivateKey.random();
-        const privateKey2 = PrivateKey.random();
-        expect(privateKey1).to.not.be.equal(privateKey2);
-    });
+  before(async function () {
+    await init();
+  });
 
-    it('should export private key to hex string', function () {
-        const privateKey = '0x9a88071ff0634f6515c7699c97d069dc4b2fa28455f6b457e92d1c1302f0c6bb';
-        expect(PrivateKey.fromHexString(privateKey).toHexString()).to.be.equal(privateKey);
-    });
+  after(function () {
+    destroy();
+  });
 
-    it('should export private key to bytes', function () {
-        expect(PrivateKey.random().toBytes().length).to.be.equal(SECRET_KEY_LENGTH);
-    });
+  it("should generate random private key", function () {
+    const privateKey1 = PrivateKey.random();
+    const privateKey2 = PrivateKey.random();
+    expect(privateKey1.toHexString()).to.not.be.equal(privateKey2.toHexString());
+  });
+
+  it("should export private key to hex string", function () {
+    const privateKey = "0x07656fd676da43883d163f49566c72b9cbf0a5a294f26808c807700732456da7";
+
+    expect(PrivateKey.fromHexString(privateKey).toHexString()).to.be.equal(privateKey);
+
+    const privateKey2 = "07656fd676da43883d163f49566c72b9cbf0a5a294f26808c807700732456da7";
+
+    expect(PrivateKey.fromHexString(privateKey2).toHexString()).to.be.equal(privateKey);
+  });
+
+  it("should export private key to bytes", function () {
+    expect(PrivateKey.random().toBytes().length).to.be.equal(SECRET_KEY_LENGTH);
+  });
+  
+  it("should not accept too short private key", function () {
+    expect(() => PrivateKey.fromHexString("0x2123")).to.throw();
+  });
 
 });

tsconfig.build.json

@@ -0,0 +1,10 @@
+{
+  "extends": "../../tsconfig",
+  "include": ["src"],
+  "compilerOptions": {
+    "typeRoots": [
+      "src/@types",
+      "../../node_modules/@types"
+    ]
+  }
+}

tsconfig.json

@@ -1,6 +1,6 @@
 {
   "extends": "../../tsconfig",
-  "include": ["src"],
+  "include": ["src", "test"],
   "compilerOptions": {
     "typeRoots": [
       "src/@types",