Should env_To checksums work with greylisting?

Gary Mills mills@cc.UManitoba.CA
Mon Dec 8 02:34:13 UTC 2003

On Sun, Dec 07, 2003 at 07:19:31PM -0700, Vernon Schryver wrote:
> > From: Gary Mills <mills@cc.UManitoba.CA>
> > One thing that I noticed was mail to my spam trap addresses has also
> > been greatly reduced.  These addresses are all whitelisted by env_To
> > in the dccm client whitelist.  I'm wondering if mail to those addresses
> > is now being embargoed by DCC?  My spam traps issue automatic complaints
> > to the sender's ISP, so I'l like them to continue to work.  Is this no
> > longer possible?
> Dccm consults the local whitelist first, the greylist system second,
> and DCC servers third.  The first unambiguous white/black or accept/reject
> answer obtained rules and aborts later consultations (with some
> complications to allow initial, greylisted transmissions to be reported
> to and counted by the DCC).
> If your traps are whitelisted by the local or dccm whiteclnt files,
> then greylisting does not apply to listed addresses or other listed
> characteristics.

Yes, that's how I expected it to work.  However, there must be something
different going on with env_To checksums.  I assume that it has to do
with multiple recipients, only one of which is whitelisted.  I assume
that with greylisting, it's the entire message that's given the
temporary failure response.  The usual trojan spam engine doesn't
retry, so the mail disappears.  Would this be correct?

> Wasn't UManitoba.CA using the deprecated server-side DCC whitelists
> because of limitations in the sizes of IP address CIDR blocks for
> client-side whitelists?  I kludged large CIDR blocks into dccm whitelists
> in version 1.2.15.

Yep, although I didn't know they were deprecated.  I haven't tried the
client-side CIDR blocks yet.  Since we have two class B networks, this
should be pretty simple.  I'll give it a try once my other changes
have settled in.

-Gary Mills-    -Unix Support-    -U of M Academic Computing and Networking-

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