This module defines the behaviour of the agent network interface
filter. A
The semantics of them and their exact signatures are explained below.
The purpose of the network interface filter is to allow for filtering of messages (accept or reject) receive and send. This is done on two levels:
The first level is at the transport entry / exit point, i.e. immediately after the receipt of the message before any message processing is done (accept_recv) and immediately before sending the message after all message processing is done (accept_send).
The second level is at the MPD entry / exit point, i.e. immediately after the basic message processing (accept_recv_pdu) / immediately before the basic message processing (accept_send_pdu).
Note that the network interface filter is something which is used
by the network interface implementation provided by the application
(
A network interface filter can e.g. be used during testing or for load
regulation. If the intended use is load regulation, see also
Legacy network interface filter modules used arguments on the form
port() = integer() > 0
pdu_type() = 'get-request' | 'get-next-request' | 'get-response' |
'set-request' | trap | 'get-bulk-request' | 'inform-request' |
report
See also the
Called at the reception of a message (before any processing has been done).
For the message to be discarded, the function must return false.
Called before the sending of a message (after all processing has been done).
For the message to be discarded, the function must return false.
Called after the basic message processing (MPD) has been done, but before the pdu is handed over to the master-agent for primary processing.
For the pdu to be discarded, the function must return false.
Called before the basic message processing (MPD) is done, when a pdu has been received from the master-agent.
For the message to be discarded all together, the function must return false.
Note that it is possible for this function to filter out targets
(but not to add its own) by returning an updated