Скачивание файла конкретным пользователем

<?php
$key = 'dfdfdsfsd23';
$decrypted = $path . $decrypted;
$ekey = hash('SHA256', $key, true);
  srand(); $iv = mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC), MCRYPT_RAND);
  if (strlen($iv_base64 = rtrim(base64_encode($iv), '=')) != 22) return false;
  $encrypted = base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $ekey, $decrypted . md5($decrypted), MCRYPT_MODE_CBC, $iv));
  return $iv_base64 . $encrypted;

<?php
$key = 'dfdfdsfsd23';
$ekey = hash('SHA256', $key, true);
  $iv = base64_decode(substr($encrypted, 0, 22) . '==');
  $encrypted = substr($encrypted, 22);
  $decrypted = rtrim(mcrypt_decrypt(MCRYPT_RIJNDAEL_128, $ekey, base64_decode($encrypted), MCRYPT_MODE_CBC, $iv), "\0\4");
  $hash = substr($decrypted, -32);
  $decrypted = substr($decrypted, 0, -32);
  if (md5($decrypted) != $hash) return false;
  return $decrypted;