QuickBlox signature generation

$body="application_id=$app_id&auth_key=$auth_key&device[platform]=$device_platform&device[udid]=$device_udid&nonce=$nonce&timestamp=$timestamp&user[login]=$user_login&user[owner_id]=$owner_id&user[password]=$user_password";
$signature = hash_hmac('sha1',$body,$auth_secret);