Restrict connections by SSID

  • As more and more people start to deploy RADIUSdesk there are always new places and ways RADIUSdesk are being deployed.
  • One such a deployment required that:
    • There be some restrictions imposed based on the SSID which the user connected to.
    • A user will be allowed to connect to one or more SSIDs.
    • This restriction will not depend or require that the packet comes from a certain vendor's equipment.
    • We have an easy way to manage the list of SSIDs.
  • With the list of requirements, a quick fix was out of the question.

How does a quick-fix look

  • We assume the incoming packet comes from a Ruckus Zonedirector.
  • The incoming packet will then contain a Ruckus specific AVP for SSID:
Ruckus-SSID = "Test2"
  • We can then simply add a private check attribute per user: That Ruckus-SSID(AVP) == (Operator) Test2(Value).
  • This unfortunately limits us to one value, one vendor and we have no easy way to get a list of all the SSIDs.

Since the quick fix did not fulfill all our desires we invented something which does: The SSIDs applet

The SSID applet

  • The SSID applet lives under Menu→Realms and Providers→SSIDs.
  • This is the place where you Create Read Update and Delete (CRUD) the pool of SSIDs.

  • Once we have our pool of SSIDs we can attach one or more to either a Voucher or Permanent user.

  • This feature is a NON disruptive feature. This means that there are no harm done if you do not use it.

How do we do it?

  • This section is for the technical minded who like to know how things work.
  • We added two internal AVPs:
    • Rd-Ssid-Check
    • Rd-Ssid-Value
  • We also added a user_ssids table to the SQL database where the username and SSIDs which the specific username are allowed to connect from is kept.
  • This mapping is managed through the RADIUSdesk front-end.
  • Rd-Ssid-Check is added to a Permanent User or Voucher's name in the radcheck table with a value of 1 to enforse SSID restrictions.
  • We use the Rd-Ssid-Value internal AVP to store the value of the SSID which we filter out of the incoming RADIUS Auth packet's Called-Station-Id.
  • This will typically be in the format of [MAC address] : [SSID].
  • Below is the logic we added to the policy.conf file.
  • Here we grab the SSID if available
RADIUSdesk_rewrite_called_station_id {
    if(Called-Station-Id =~ /^([0-9a-f]{2})[-:]?([0-9a-f]{2})[-:.]?([0-9a-f]{2})[-:]?([0-9a-f]{2})[-:.]?([0-9a-f]{2})[-:]?([0-9a-f]{2})[-:]?([-a-z0-9_. ]*)?/i){
            update control {
                Rd-Ssid-Value := "%{7}"
	else {
    else {
  • Here we check if we need to enforce this SSID check
RADIUSdesk_user_ssid_check {
    #__We check if the user is flagged to only connect through certain SSIDs (Rd-Ssid-Check == 1)_
    #__If so we try to find the SSID and see if this ssid is allowed for the specific user________
    #If it is present....
        #If it is == 1
        if("%{control:Rd-Ssid-Check}" == 1){
                if("%{sql:SELECT COUNT(*) FROM user_ssids WHERE username= '%{request:User-Name}' AND ssidname= '%{control:Rd-Ssid-Value}'}" > 0){
                else {
                    update reply {
                         Reply-Message := "User %{request:User-Name} has not permission to connect through SSID: %{control:Rd-Ssid-Value}"
           else {
               update reply{
                   Reply-Message := "No SSID available to evaluate SSID restriction"