Sam Varshavchik wrote:
Jeff Potter writes:
Hi All,
I'm wondering if there's any way that Courier can do this:
1. Receive a message on SMTP
2. After getting ".<CR><LF>", but before responding "250 Ok"...
3. Attempt to deliver the mail: if there are delivery instructions in
a .courier file, run them.
4. If one of the delivery instructions generates a hard error, on the
SMPT layer respond with "5xx Unable to deliver message, local
delivery instructions failed."
I know that Courier can check if dash-extension addresses are
existent if the homedir is o+rx, but what I'm hoping is that this can
be extended to actually *running* the users delivery instructions so
that any DSNs that do get generated, get generated out the SMTP layer
so that invalid from addresses don't cause double bounces to my local
postmaster account.
Doable?
There's a similar facility that provides for executing a restricted
maildrop recipe, which can examine the message's contents, and
selectively accept or reject the message.
It's rather difficult/tricky to set up.
Begin by reading the localmailfilter man page. All of it. Paragraph
by paragraph.
I looked at this previously and it does not seem to fit my bill completely.
Can I whitelist postmaster@ and abuse@ unconditionally? Or does "accept
message onconditionally" only apply to the contentfilter but blocklists
are still applied? I think the latter, as blocklists are applied earlier
in the SMTP phase.
If I understand the manpage correct, these filters are not run for
messages submitted on the MSA port?
Martijn