Hi,
I think there is a bug in handling of sender_dependent_default_transport_maps
within smtpd when default_transport is set to error:...
I'm configuring postfix as follows using default_transport and
sender_dependent_default_transport_maps to reject all external
outgoing mail, unless the envelope sender comes from a particular
domain (yanofsky.org):
default_transport = error:External delivery disabled
sender_dependent_default_transport_maps = inline:{
@yanofsky.org=smtp:[smtp-relay.gmail.com]:587 }
This works correctly for messages sent locally though the sendmail
command. But it doesn't work for messages that come in through smtpd.
The problem is that smtpd rejects all external outgoing messages after
the RCPT command, even when the sender is from @yanofsky.org.
Looking at the smtpd source code, the problem seems to be that instead
of smtpd calling the resolve_clnt_query_from() function which takes
the sender into account, it always calls the resolve_clnt_query()
function, which ignores the message sender.
The exact point of failure happens in the
strcmp(STR(reply->transport), MAIL_SERVICE_ERROR) check inside the
check_rcpt_maps() function when it is called by
check_recipient_rcpt_maps(), which is called by smtpd_check_rcpt(),
The problem looks like it could be straightforward to fix if the
resolve_clnt_query() call inside smtpd were changed to
resolve_clnt_query_from(), but I haven't tried making this change yet,
and I don't know what other effects this might have.
Other notes: I'm running postfix-3.1.1, and the exact smtpd failure message is:
Jun 14 17:40:51 jumpy postfix/smtpd[31276]: NOQUEUE: reject: RCPT from
jumpy[2600:3c03::f03c:91ff:fe55:105d]: 550 5.1.1
<russ+t...@yanofsky.org>: Recipient address rejected: External
delivery disabled; from=<russ+t...@yanofsky.org>
to=<russ+t...@yanofsky.org> proto=ESMTP helo=<jumpy>
