| <?php | 
 | function generateRandomString($length = 96) { | 
 |     $characters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'; | 
 |     $charactersLength = strlen($characters); | 
 |     $randomString = ''; | 
 |     for ($i = 0; $i < $length; $i++) { | 
 |         $randomString .= $characters[rand(0, $charactersLength - 1)]; | 
 |     } | 
 |     return $randomString; | 
 | } | 
 |  | 
 | function getClientIP():string | 
 | { | 
 |     $keys=array('HTTP_CLIENT_IP','HTTP_X_FORWARDED_FOR','HTTP_X_FORWARDED','HTTP_FORWARDED_FOR','HTTP_FORWARDED','REMOTE_ADDR'); | 
 |     foreach($keys as $k) | 
 |     { | 
 |         if (!empty($_SERVER[$k]) && filter_var($_SERVER[$k], FILTER_VALIDATE_IP)) | 
 |         { | 
 |             return $_SERVER[$k]; | 
 |         } | 
 |     } | 
 |     return false; | 
 | } | 
 | ?> |