12.2. Handling Requests Previous topic Parent topic Child topic Next topic

After construction and initialisation, your instance will be called upon to handle requests that are sent to it. For each request received, the Handler.pm module will call ($result, $reason) = Radius::AuthXYZ->handle_request($p, $rp), where $p is a reference to the Radius::Radius packet received from the client, and $rp is an empty reply packet, ready for you to fill. Client.pm and Handler.pm will filter out duplicate requests, requests from unknown clients and requests with bad authenticators, so your handle_request will only be called for new, good requests from known clients. The contents of the request will have been unpacked into the Radius::Radius instance passed in as $p, so you can immediately start examining attributes and doing things.
handle_request returns an array. The first element is a result code, and the second is an optional reason message.
The result code from handle_request will indicate whether Handler.pm should automatically send the reply to the original requester:
  • If handle_request returns $main::ACCEPT, Handler.pm will send back $rp as an accept message appropriate to the type of request received (i.e. it will turn $rp into an Access-Accept if the original request was an Access-Request). In the case of Accounting-Request, this is the only result code that will cause a reply to be sent back.
  • If handle_request returns $main::REJECT, Handler.pm will send back $rp as a reject message appropriate to the type of request received (i.e. it will turn $rp into an Access-Reject if the original request was an Access-Request). In this case the reason message should be supplied.
  • If handle_request returns $main::CHALLENGE, Handler.pm will send back $rp as a Access-Challenge message.
  • If handle_request returns $main::IGNORE, Handler.pm will not send any reply back to the originating client. You should only use this if the request is to be completely ignored, or if your module undertakes to send its own reply some time in the future. If the Handler or Realm has more than one AuthBy handler module specified, it will continue calling handlers in the order in which they were specified until one returns something other than $main::IGNORE. You can change this behaviour with AuthByPolicy, for more information, see Section 3.25.16. AuthByPolicy.
Your handle_request function may want to use utility functions in Radius::Radius (see Radius.pm) to examine attributes in the incoming request, and to construct replies. There are some convenience routines in Client.pm for packing and sending replies to the original requester, such as
$p->{Client}->replyTo($rp, $p);
If your handler cannot successfully handle the request, perhaps due to some unforeseen event, software failure, system unavailability etc., it is common to not reply at all to the original request. This will usually force the original NAS to retransmit to another server as a fallback. You can do this by returning $main::IGNORE from handle_request.