title: Is it safe to trust $_SERVER['REMOTE_ADDR']?
body: <p>Is it safe to trust <code>$_SERVER['REMOTE_ADDR']</code>? Can it be substituted by changing the header of request or something like that?</p>
  
  <p>Is it safe to write something like that?</p>
  
  <pre><code>if ($_SERVER['REMOTE_ADDR'] == '222.222.222.222') { // my ip address
      $grant_all_admin_rights = true;
  }
  </code></pre>