metamask-extension/app/scripts/phishing-detect.js

import querystring from 'querystring';
import { EventEmitter } from 'events';
import dnode from 'dnode';
import PortStream from 'extension-port-stream';
import extension from 'extensionizer';
import { setupMultiplex } from './lib/stream-utils';
import { getEnvironmentType } from './lib/util';
import ExtensionPlatform from './platforms/extension';

document.addEventListener('DOMContentLoaded', start);

function start() {
  const hash = window.location.hash.substring(1);
  const suspect = querystring.parse(hash);

  document.getElementById('csdbLink').href = `https://cryptoscamdb.org/search`;

  global.platform = new ExtensionPlatform();

  const extensionPort = extension.runtime.connect({
    name: getEnvironmentType(),
  });
  const connectionStream = new PortStream(extensionPort);
  const mx = setupMultiplex(connectionStream);
  setupControllerConnection(
    mx.createStream('controller'),
    (err, metaMaskController) => {
      if (err) {
        return;
      }

      const continueLink = document.getElementById('unsafe-continue');
      continueLink.addEventListener('click', () => {
        metaMaskController.safelistPhishingDomain(suspect.hostname);
        window.location.href = suspect.href;
      });
    },
  );
}

function setupControllerConnection(connectionStream, cb) {
  const eventEmitter = new EventEmitter();
  // the "weak: false" option is for nodejs only (eg unit tests)
  // it is a workaround for node v12 support
  const metaMaskControllerDnode = dnode(
    {
      sendUpdate(state) {
        eventEmitter.emit('update', state);
      },
    },
    { weak: false },
  );
  connectionStream.pipe(metaMaskControllerDnode).pipe(connectionStream);
  metaMaskControllerDnode.once('remote', (backgroundConnection) =>
    cb(null, backgroundConnection),
  );
}