Duplicate body checksum...

Vernon Schryver <vjs@calcite.rhyolite.com> writes:

> Is there some way to use dccproc to reject spam without filtering
> in the MUA such as with the gnus filters described in that web page?

Probably, using something like dccproc piped into maildrop or the
other way 'round.  I need to look at the changes you made in the most
recent version for regexps and such.

> If you must mess with the MUA, why not do it all in the MUA and not
> mess with the MTA by having the MUA pipe the message through dccproc
> and using the threshold mechanism in version 1.0.43, as in
> `dccproc -w ~/whiteclnt -c CMN,20`  and using the dccproc exit code?

This new -c option is something I need to look at; I'm still running
1.0.42.  I just wanted to get something quick-n-dirty running to see
how DCC performed.  When I get a bit, I'll get 1.0.43 and try and do
something a bit less hackish.  

On the other hand, it's kinda convenient to have the .qmail part which
invokes DCC separate from the MUA, so in the first part I can add the
header, and the second I can decide what to do.   If I were an ISP,
I'd want to configure my mailserver to run dccproc on all my messages,
and then let users decide what to do based on the header.  I'm talking
about this now with some folks with whom I help run an ISP.

Right now, I'm too new to DCC to feel comfortable making rejections
automatic.

> 
> On the other hand, is there a way to have qmail pay attention to
> the dccproc exit code with something like
> 
>  |preline /usr/local/bin/dccproc -w $USER/.dcc/whiteclnt -c CMN,50 | ...
> 
> (I've no real notion what "|preline" does, so that probably makes no sense
> except perhaps by analogy)

Preline pretty much just adds the mbox style "From ..." line to a
message, so dccproc can find that field.  I can have qmail pay
attention to return codes; DJB (qmail's author) has his own idea about
exit codes, so I could always wrap in a script if needed; or use
maildrop.   But if it *did* understand at least a non-zero exit code,
the ".qmail" (kinda like .forward) file could be simplified to:

  |preline /usr/local/bin/dccproc -w $USER/.dcc/whiteclnt -c CMN,50
  ./Maildir/

What this says is first run the message through dccproc.  If you get a
zero exit, then run the message into the Maildir; if non-zero, don't
do anything further with the message.  The one thing this would miss
out on is putting the X-DCC line into the message since processing the
.qmail file only depends on on the exit code, it's not using the pipe
as a true content filter. For that, I can use my redelivery hack or
maildrop and its friends. 

Again, sounds like I really need to look at 1.0.43 pronto!

Thanks.