dcrouter/test/suite/security/test.authorization.ts

import { tap, expect } from '@git.zone/tstest/tapbundle';
import * as plugins from '../../../ts/plugins.js';
import * as net from 'net';
import { startTestServer, stopTestServer } from '../../helpers/server.loader.js'
import type { ITestServer } from '../../helpers/server.loader.js';

const TEST_PORT = 2525;
let testServer: ITestServer;

tap.test('setup - start test server', async (toolsArg) => {
  testServer = await startTestServer({ port: TEST_PORT });
  await toolsArg.delayFor(1000);
});

tap.test('Authorization - Valid sender domain', async (tools) => {
  const done = tools.defer();
  
  const socket = net.createConnection({
    host: 'localhost',
    port: TEST_PORT,
    timeout: 30000
  });
  
  let dataBuffer = '';
  let step = 'greeting';
  
  socket.on('data', (data) => {
    dataBuffer += data.toString();
    console.log('Server response:', data.toString());
    
    if (step === 'greeting' && dataBuffer.includes('220 ')) {
      step = 'ehlo';
      socket.write('EHLO localhost\r\n');
      dataBuffer = '';
    } else if (step === 'ehlo' && dataBuffer.includes('250')) {
      step = 'mail';
      // Use valid sender domain (localhost)
      socket.write('MAIL FROM:<test@localhost>\r\n');
      dataBuffer = '';
    } else if (step === 'mail' && dataBuffer.includes('250')) {
      step = 'rcpt';
      socket.write('RCPT TO:<recipient@example.com>\r\n');
      dataBuffer = '';
    } else if (step === 'rcpt') {
      // Valid sender should be accepted
      const accepted = dataBuffer.includes('250');
      console.log(`Valid sender domain ${accepted ? 'accepted' : 'rejected'}`);
      
      expect(accepted).toEqual(true);
      
      socket.write('QUIT\r\n');
      socket.end();
      done.resolve();
    }
  });
  
  socket.on('error', (err) => {
    console.error('Socket error:', err);
    done.reject(err);
  });
  
  await done.promise;
});

tap.test('Authorization - External sender domain', async (tools) => {
  const done = tools.defer();
  
  const socket = net.createConnection({
    host: 'localhost',
    port: TEST_PORT,
    timeout: 30000
  });
  
  let dataBuffer = '';
  let step = 'greeting';
  
  socket.on('data', (data) => {
    dataBuffer += data.toString();
    console.log('Server response:', data.toString());
    
    if (step === 'greeting' && dataBuffer.includes('220 ')) {
      step = 'ehlo';
      socket.write('EHLO external.com\r\n');
      dataBuffer = '';
    } else if (step === 'ehlo' && dataBuffer.includes('250')) {
      step = 'mail';
      // Use external sender domain
      socket.write('MAIL FROM:<test@external.com>\r\n');
      dataBuffer = '';
    } else if (step === 'mail') {
      if (dataBuffer.includes('250')) {
        step = 'rcpt';
        socket.write('RCPT TO:<recipient@example.com>\r\n');
        dataBuffer = '';
      } else if (dataBuffer.includes('530')) {
        // Authentication required
        console.log('External sender requires authentication');
        expect(true).toEqual(true);
        
        socket.write('QUIT\r\n');
        socket.end();
        done.resolve();
      } else if (dataBuffer.includes('550') || dataBuffer.includes('553')) {
        // Rejected for policy reasons
        console.log('External sender rejected by policy');
        expect(true).toEqual(true);
        
        socket.write('QUIT\r\n');
        socket.end();
        done.resolve();
      }
    } else if (step === 'rcpt') {
      // Check response
      const accepted = dataBuffer.includes('250');
      const authRequired = dataBuffer.includes('530');
      const rejected = dataBuffer.includes('550') || dataBuffer.includes('553');
      
      console.log(`External sender: accepted=${accepted}, authRequired=${authRequired}, rejected=${rejected}`);
      expect(accepted || authRequired || rejected).toEqual(true);
      
      socket.write('QUIT\r\n');
      socket.end();
      done.resolve();
    }
  });
  
  socket.on('error', (err) => {
    console.error('Socket error:', err);
    done.reject(err);
  });
  
  await done.promise;
});

tap.test('Authorization - Relay attempt rejection', async (tools) => {
  const done = tools.defer();
  
  const socket = net.createConnection({
    host: 'localhost',
    port: TEST_PORT,
    timeout: 30000
  });
  
  let dataBuffer = '';
  let step = 'greeting';
  
  socket.on('data', (data) => {
    dataBuffer += data.toString();
    console.log('Server response:', data.toString());
    
    if (step === 'greeting' && dataBuffer.includes('220 ')) {
      step = 'ehlo';
      socket.write('EHLO external.com\r\n');
      dataBuffer = '';
    } else if (step === 'ehlo' && dataBuffer.includes('250')) {
      step = 'mail';
      // External sender
      socket.write('MAIL FROM:<test@external.com>\r\n');
      dataBuffer = '';
    } else if (step === 'mail') {
      if (dataBuffer.includes('250')) {
        step = 'rcpt';
        // Try to relay to another external domain (should be rejected)
        socket.write('RCPT TO:<recipient@another-external.com>\r\n');
        dataBuffer = '';
      } else {
        // MAIL FROM already rejected
        console.log('External sender rejected at MAIL FROM');
        expect(true).toEqual(true);
        
        socket.write('QUIT\r\n');
        socket.end();
        done.resolve();
      }
    } else if (step === 'rcpt') {
      // Relay attempt should be rejected
      const rejected = dataBuffer.includes('550') || 
                      dataBuffer.includes('553') || 
                      dataBuffer.includes('530') ||
                      dataBuffer.includes('554');
      
      console.log(`Relay attempt ${rejected ? 'properly rejected' : 'unexpectedly accepted'}`);
      expect(rejected).toEqual(true);
      
      socket.write('QUIT\r\n');
      socket.end();
      done.resolve();
    }
  });
  
  socket.on('error', (err) => {
    console.error('Socket error:', err);
    done.reject(err);
  });
  
  await done.promise;
});

tap.test('Authorization - IP-based restrictions', async (tools) => {
  const done = tools.defer();
  
  const socket = net.createConnection({
    host: 'localhost',
    port: TEST_PORT,
    timeout: 30000
  });
  
  let dataBuffer = '';
  let step = 'greeting';
  
  socket.on('data', (data) => {
    dataBuffer += data.toString();
    console.log('Server response:', data.toString());
    
    if (step === 'greeting' && dataBuffer.includes('220 ')) {
      step = 'ehlo';
      // Use IP address in EHLO
      socket.write('EHLO [127.0.0.1]\r\n');
      dataBuffer = '';
    } else if (step === 'ehlo' && dataBuffer.includes('250')) {
      step = 'mail';
      socket.write('MAIL FROM:<test@localhost>\r\n');
      dataBuffer = '';
    } else if (step === 'mail' && dataBuffer.includes('250')) {
      step = 'rcpt';
      socket.write('RCPT TO:<recipient@example.com>\r\n');
      dataBuffer = '';
    } else if (step === 'rcpt') {
      // Localhost IP should typically be accepted
      const accepted = dataBuffer.includes('250');
      const rejected = dataBuffer.includes('550') || dataBuffer.includes('553');
      
      console.log(`IP-based authorization: ${accepted ? 'accepted' : 'rejected'}`);
      expect(accepted || rejected).toEqual(true); // Either is valid based on server config
      
      socket.write('QUIT\r\n');
      socket.end();
      done.resolve();
    }
  });
  
  socket.on('error', (err) => {
    console.error('Socket error:', err);
    done.reject(err);
  });
  
  await done.promise;
});

tap.test('Authorization - Case sensitivity in addresses', async (tools) => {
  const done = tools.defer();
  
  const socket = net.createConnection({
    host: 'localhost',
    port: TEST_PORT,
    timeout: 30000
  });
  
  let dataBuffer = '';
  let step = 'greeting';
  
  socket.on('data', (data) => {
    dataBuffer += data.toString();
    console.log('Server response:', data.toString());
    
    if (step === 'greeting' && dataBuffer.includes('220 ')) {
      step = 'ehlo';
      socket.write('EHLO localhost\r\n');
      dataBuffer = '';
    } else if (step === 'ehlo' && dataBuffer.includes('250')) {
      step = 'mail';
      // Use mixed case in email address
      socket.write('MAIL FROM:<TeSt@LoCaLhOsT>\r\n');
      dataBuffer = '';
    } else if (step === 'mail' && dataBuffer.includes('250')) {
      step = 'rcpt';
      // Mixed case recipient
      socket.write('RCPT TO:<ReCiPiEnT@ExAmPlE.cOm>\r\n');
      dataBuffer = '';
    } else if (step === 'rcpt') {
      // Email addresses should be case-insensitive
      const accepted = dataBuffer.includes('250');
      console.log(`Mixed case addresses ${accepted ? 'accepted' : 'rejected'}`);
      
      expect(accepted).toEqual(true);
      
      socket.write('QUIT\r\n');
      socket.end();
      done.resolve();
    }
  });
  
  socket.on('error', (err) => {
    console.error('Socket error:', err);
    done.reject(err);
  });
  
  await done.promise;
});

tap.test('cleanup - stop test server', async () => {
  await stopTestServer(testServer);
});

tap.start();