[Greylist-users] Re: GroupWise is the Devil

[Philip Kizer]

Scott Nelson <scott at spamwolf.com> wrote:
>Note that even if this bug is fixed, there will still be a lot
>of broken mailers for a long time.

It's a given there's a few really broken ones, hopefully only a very few
like Groupwise.


>The solution is to fail the DATA with a 4xx /as well/ if there
>was at least one RCPT that was 4xx.

If you check out the URLs marius posted, you'll see the Groupwise SMTP
exchange with the destination system looked like this:

  220 megatron.alpha1.net. ESMTP Sendmail 8.1
  EHLO apcis7.tamu.edu.
  250-megatron.alpha1.net. Hello cis-gw.tamu.
  MAIL FROM: <philip-kizer at cis-gw.tamu.edu>
  250 2.1.0 <philip-kizer at cis-gw.tamu.edu>
  RCPT TO: <marius at alpha1.net>
  451 4.7.1 Please try again later (TEMPFAIL
  Quit
  221 2.0.0 megatron.alpha1.net closing conn

That did not even leave an option of responding to the DATA phase with a
4xx since it didn't begin one.  Groupwise is just broken, such as per
RFC2821, notably sections 4.2.1 and 4.5.4.1 ("mail that cannot be
transmitted immediately MUST be queued and ... retried", as opposed their
taking a 451+4.7.1 and immediately turning it into a message claiming there
was a "551 No valid recipients" response).


-philip

-- 
Philip Kizer, Senior Lead Systems Engineer, Texas A&M University
USENIX Liaison to Texas A&M University         <usenix at tamu.edu>
Texas A&M CIS Operating Systems Group, Unix   <pckizer at tamu.edu>