TRCL-3691 v4-client: Add signing function for push (#233)

* Add native function to sign push notification token registration payload

* Bump version

* Fix

* Clean up

* Clean up

.gitignore

@@ -0,0 +1 @@
+.idea

v4-client-js/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@dydxprotocol/v4-client-js",
-  "version": "1.3.1",
+  "version": "1.3.2",
   "description": "General client library for the new dYdX system (v4 decentralized)",
   "main": "build/src/index.js",
   "scripts": {

v4-client-js/src/clients/native.ts

@@ -16,7 +16,7 @@ import Long from 'long';
 import { BECH32_PREFIX, GAS_MULTIPLIER, NOBLE_BECH32_PREFIX } from '../lib/constants';
 import { UserError } from '../lib/errors';
 import { ByteArrayEncoding, encodeJson } from '../lib/helpers';
-import { deriveHDKeyFromEthereumSignature } from '../lib/onboarding';
+import { deriveHDKeyFromEthereumSignature, deriveHDKeyFromMnemonic } from '../lib/onboarding';
 import { NetworkOptimizer } from '../network_optimizer';
 import { CompositeClient, MarketInfo } from './composite-client';
 import {
@@ -147,6 +147,12 @@ export async function connectWallet(mnemonic: string): Promise<string> {
     globalThis.wallet = await LocalWallet.fromMnemonic(mnemonic, BECH32_PREFIX);
     globalThis.nobleWallet = await LocalWallet.fromMnemonic(mnemonic, NOBLE_BECH32_PREFIX);
 
+    const { privateKey, publicKey } = deriveHDKeyFromMnemonic(mnemonic);
+    globalThis.hdKey = {
+      privateKey,
+      publicKey,
+    };
+
     try {
       await globalThis.nobleClient?.connect(globalThis.nobleWallet);
     } catch (e) {
@@ -1306,6 +1312,34 @@ export async function signCompliancePayload(payload: string): Promise<string> {
   }
 }
 
+export async function signPushNotificationTokenRegistrationPayload(payload: string): Promise<string> {
+  try {
+    const json = JSON.parse(payload);
+    const message = json.message;
+    if (message === undefined) {
+      throw new UserError('message is not set');
+    }
+    if (!globalThis.hdKey?.privateKey || !globalThis.hdKey?.publicKey) {
+      throw new Error('Missing hdKey');
+    }
+
+    const timestampInSeconds = Math.floor(Date.now() / 1000);
+    const messageToSign: string = `${message}:REGISTER_TOKEN"${''}:${timestampInSeconds}`;
+    const messageHash = sha256(Buffer.from(messageToSign));
+
+    const signed = await Secp256k1.createSignature(messageHash, globalThis.hdKey.privateKey);
+    const signedMessage = signed.toFixedLength();
+
+    return encodeJson({
+      signedMessage: Buffer.from(signedMessage).toString('base64'),
+      publicKey: Buffer.from(globalThis.hdKey.publicKey).toString('base64'),
+      timestamp: timestampInSeconds,
+    });
+  } catch (error) {
+    return wrappedError(error);
+  }
+}
+
 export async function setSelectedGasDenom(gasDenom: string): Promise<string> {
   try {
     const client = globalThis.client;

v4-client-js/src/lib/onboarding.ts

@@ -27,19 +27,11 @@ export const exportMnemonicAndPrivateKey = (
   publicKey: Uint8Array | null;
 } => {
   const mnemonic = entropyToMnemonic(entropy, wordlist);
-  const seed = mnemonicToSeedSync(mnemonic);
-
-  const hdkey = HDKey.fromMasterSeed(seed);
-  const derivedHdkey = hdkey.derive(path);
-
-  if (!hdkey.privateKey) {
-    throw new Error('null hd key');
-  }
-
+  const { privateKey, publicKey } = deriveHDKeyFromMnemonic(mnemonic, path);
   return {
     mnemonic,
-    privateKey: derivedHdkey.privateKey,
-    publicKey: derivedHdkey.publicKey,
+    privateKey,
+    publicKey,
   };
 };
 
@@ -67,3 +59,38 @@ export const deriveHDKeyFromEthereumSignature = (
   const entropy = keccak256(rsValues);
   return exportMnemonicAndPrivateKey(entropy);
 };
+
+/**
+ * @description Derive priv/pub keys from mnemonic and BIP44 HD path
+ *
+ * @url https://github.com/confio/cosmos-hd-key-derivation-spec#bip44
+ *
+ * @param mnemonic used to generate seed
+ *
+ * @param path BIP44 HD Path. Default is The Cosmos Hub path
+ *
+ * @throws Error if the hdkey does not exist
+ *
+ * @returns Priv/pub keys
+ */
+export const deriveHDKeyFromMnemonic = (
+  mnemonic: string,
+  path: string = "m/44'/118'/0'/0/0",
+): {
+  privateKey: Uint8Array | null;
+  publicKey: Uint8Array | null;
+} => {
+  const seed = mnemonicToSeedSync(mnemonic);
+
+  const hdkey = HDKey.fromMasterSeed(seed);
+  const derivedHdkey = hdkey.derive(path);
+
+  if (!hdkey.privateKey) {
+    throw new Error('null hd key');
+  }
+
+  return {
+    privateKey: derivedHdkey.privateKey,
+    publicKey: derivedHdkey.publicKey,
+  };
+};