signal-password-helper.js

const { app, safeStorage } = require('electron');
const { join } = require('node:path');
const { readFileSync, writeFileSync } = require('node:fs');

const folder = join(app.getPath('appData'), 'Signal');
app.setPath('userData', folder);
app.setName('Signal');

app.on('ready', () => {
  const configPath = join(folder, 'config.json');

  const json = readFileSync(configPath, 'utf8');
  // Save backup
  writeFileSync(join(folder, 'config.json.bak'), json);

  const config = JSON.parse(json);
  if (!config.encryptedKey) {
    console.error('Already decrypted');
    app.quit(1);
    return;
  }
  const encryptedKey = Buffer.from(config.encryptedKey, 'hex');
  const decrypted = safeStorage.decryptString(encryptedKey);
  const newConfig = {
    ...config,
    encryptedKey: undefined,
    key: decrypted,
  };
  const newJson = JSON.stringify(newConfig, null, 2);
  writeFileSync(configPath, newJson);

  console.log('Success');
  app.quit();
})