Wifi Authorization using Curl - php

Question

session_start();
function sendAuthorization($id, $minutes)
{
$unifiServer = "https://xxx.xxx.xxx.xxx:xxxx";
$unifiUser = "xxxxx";
$unifiPass = "xxxxx";
// Start Curl for login
$ch = curl_init();
// We are posting data
curl_setopt($ch, CURLOPT_POST, TRUE);
// Set up cookies
$cookie_file = "/tmp/unifi_cookie";
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookie_file);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookie_file);
// Allow Self Signed Certs
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);
// Force SSL3 only
curl_setopt($ch, CURLOPT_SSLVERSION, 3);
// Login to the UniFi controller
curl_setopt($ch, CURLOPT_URL, "$unifiServer/login");
curl_setopt($ch, CURLOPT_POSTFIELDS,
"login=login&username=$unifiUser&password=$unifiPass");
// send login command
curl_exec ($ch);
// Send user to authorize and the time allowed
$data = json_encode(array(
'cmd'=>'authorize-guest',
'mac'=>$id,
'minutes'=> $minutes));
// Send the command to the API
curl_setopt($ch, CURLOPT_URL, $unifiServer.'/api/cmd/stamgr');
curl_setopt($ch, CURLOPT_POSTFIELDS, 'json='.$data);
curl_exec ($ch);
// Logout of the UniFi Controller
curl_setopt($ch, CURLOPT_URL, $unifiServer.'/logout');
curl_exec ($ch);
curl_close ($ch);
unset($ch);
}
(thought I would add the code first)
would anyone out there know how to turn this around so that I could call the function so the user IS NOT authorized?
Im making a captive portal. this is a authorized.php page, but on this i would like to have a function which is unauthorize within this page, to call it if some information is missing.
Thanks,
Andrew