[Mimedefang] Not piggybacking HELO checks

[Philip Prindeville]

BTW:  Are there patches to support calling filter_helo directly, rather
than bundling it as part of filter_sender?

Here's why:  certain sites that don't get a lot of external mail but do
need to be "open" to the outside all the same (and no email addresses on
these machines are published in any way to the outside world) have
open security, i.e. they will answer a "EXPN" or "VRFY".

But they shouldn't do this if a connection comes in from a site we don't
trust, and indeed if we see a bogus HELO, I'd like to give a 5xx
response right then and there.

So... what's involved in getting mimedefang to look at and respond
to the HELO command directly?

Has anyone looked into this?

Thanks,

-Philip