run method

Implementation

@override
Future<AuditResult> run(TelnetTransport transport) async {
  final completer = Completer<AuditResult>();

  final subscription = transport.events.listen(
    (event) {
      if (!completer.isCompleted) {
        // If we get any response after our malformed sequence + AYT, it means server survived.
        completer.complete(
          AuditResult(
            name,
            AuditStatus.pass,
            'Server remained responsive after malformed IAC sequences. Received: ${event.type}',
          ),
        );
      }
    },
    onError: (error) {
      if (!completer.isCompleted) {
        completer.complete(
          AuditResult(
            name,
            AuditStatus.fail,
            'Connection error after malformed IAC sequences: $error',
          ),
        );
      }
    },
    onDone: () {
      if (!completer.isCompleted) {
        completer.complete(
          AuditResult(
            name,
            AuditStatus.fail,
            'Connection closed after malformed IAC sequences.',
          ),
        );
      }
    },
  );

  try {
    // 1. Partial IAC
    transport.write(Uint8List.fromList([255]));
    await Future.delayed(const Duration(milliseconds: 100));

    // 2. Invalid command (100)
    transport.write(Uint8List.fromList([255, 100]));
    await Future.delayed(const Duration(milliseconds: 100));

    // 3. Unclosed SB
    transport.write(Uint8List.fromList([255, 250, 1, 2, 3]));
    await Future.delayed(const Duration(milliseconds: 100));

    // 4. AYT to check responsiveness
    transport.write(Uint8List.fromList([255, 246]));

    return await completer.future.timeout(
      const Duration(seconds: 5),
      onTimeout: () {
        return AuditResult(
          name,
          AuditStatus.fail,
          'Timeout waiting for response after malformed sequences.',
        );
      },
    );
  } catch (e) {
    if (e is TimeoutException) {
      return AuditResult(
        name,
        AuditStatus.fail,
        'Timeout waiting for response after malformed sequences.',
      );
    }
    return AuditResult(
      name,
      AuditStatus.fail,
      'Exception during Malformed IAC probe: $e',
    );
  } finally {
    await subscription.cancel();
  }
}