Quick Start

Silent Shard Duo consists of two parties:

• Mobile SDK React Native
• An MPC server

There are 3 core MPC actions that you can perform:

• Keygen: Generate a new MPC wallet.
• Sign: Sign a message using the MPC wallet.
• Refresh: Refresh your wallet's secret data, without changing your address!

info

For a list of all supported actions go to Supported Features

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Quick Intuition

To get a quick intuition of the system let's take a look at a high-level diagram

info

The parties take part in a round based protocol and pass messages over Websockets

The best way to get started would be to run a local server and play with the SDK.

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Start the Server

Install Docker and the docker-compose.

For local setup, let's use this example docker-compose.yml

docker-compose.yml

version: '3.1'

services:

  db:
    image: postgres:14
    restart: always
    environment:
      POSTGRES_PASSWORD: sigpair
      POSTGRES_USER: sigpair
      POSTGRES_DB: sigpair
    ports:
      - 5432:5432

  sigpair:
    image: ghcr.io/silence-laboratories/duo-server:v2-latest
    restart: always
    environment:
      PGHOST: db
      PGUSER: sigpair
      PGDATABASE: sigpair
      PGPASSWORD: sigpair
    ports:
      - 8080:8080
    depends_on:
      - db

info

For details on the environment variables, please check the Duo Server section.

Now let's start the server by running

shell

docker-compose up

If everything was setup correctly, the server should be running with these logs

duo-server-1  | (timestamp) DEBUG duo_node: listening on 0.0.0.0:8080
duo-server-1  | (timestamp)  INFO duo_node: Server Public key: YOUR_SERVER_PUBLIC_KEY

Great! The server is now setup to perform MPC actions with our mobile.

To continue, please copy the public key logged by the server on startup (YOUR_SERVER_PUBLIC_KEY)

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Setup the Mobile SDK (React Native)

Create a new React Native project

npx react-native init SilentMPC

After the project is created, configure the @silencelaboratories/silent-shard-sdk as the installation guide.

Our package heavily encodes and decodes the String using Buffer objects, so let's add to the project.

yarn add buffer

Run the MPC operations

Import and Setup the SDK

Copy the following code to the App.tsx file and paste the previously copied server public key in place of YOUR_SERVER_PUBLIC_KEY

App.tsx

import * as React from 'react';
import { CloudWebSocketClient, EcdsaSession, type SessionConfig } from '@silencelaboratories/silent-shard-sdk';
import { Buffer } from 'buffer';

global.Buffer = Buffer;

// Set the Server URL
const CLOUD_NODE_URI = 'localhost:8080';
// Set the Server's verifying key.
const cloudVerifyingKey = 'YOUR_SERVER_PUBLIC_KEY';

export default function App() {
  React.useEffect(() => {
    // We will MPC functions here
    const test = async () => {
      const cloudClient = new CloudWebSocketClient(CLOUD_NODE_URI, false);

      // Create MPC session configuration
      const config: SessionConfig = {
        cloudVerifyingKey: cloudVerifyingKey,
        client: cloudClient,
      };
      // Initialize the session
      const session = new EcdsaSession(config);

      // Keygen
      const keyshare = await session.keygen();
      console.log('Generated keyshare: ', keyshare);

      // Get public key of newly generated wallet
      const publicKey = keyshare.publicKeyBase64;
      console.log('Generated public key: ', publicKey);

      // Keccak256 Hash("Trusted Third Parties are Security Holes")
      const messageHash = '53c48e76b32d4fb862249a81f0fc95da2d3b16bf53771cc03fd512ef5d4e6ed9';

      // Signature generation
      const signature = await session.sign({
        keyshare,
        messageHash,
        derivationPath: 'm',
      });

      console.log('Generated signature: ', signature);
    };
    test();
  }, []);

  return null;
}