[Mimedefang] md_check_against_smtp_server and md_graphdefang_log

[kd6lvw at yahoo.com]

--- On Fri, 3/22/13, James Curtis <jameswcurtis at hotmail.com> wrote:
> I'm trying to piece together a filter
> that logs and blocks traffic that is unnecessary.  I
> can't get md_graphdefang_log to put in an entry for items
> that are refused because of 'User unknown' responses. 

The problem is that when Sendmail has already determined an error has occurred based on its rulesets, the corresponding milter function is NOT called - thus there will be no such log entry for the above error unless your MD filter code determines that the user is unknown, not sendmail.

I don't know whether other MTAs (e.g. postfix) that have the milter interface behave similarly.

This means that the only things that MD will get to log are things that passed the MTA's checks.  In part, this makes sense in that there's no reason to call the milter if the MTA has already determined an error.