Blocking Delivery Status Notifications?

[Remco Barendse]

On Tue, 15 Oct 2002, Julian Field wrote:

> At 11:38 15/10/2002, you wrote:
> >Isn't it possible to have MailScanner reset the DSN flag in the envelope
> >as an option ? (Maybe grep and delete the DSN enabling part)?
> >
> >It's very annoying that people from outside can see who / when reads their
> >e-mails especially with e-mails that are quitly forwarded to laptops  or
> >mobile phones! Think other ppl must have this problem as well?
>
> But that's the whole point of using DSN's. They are there so that the
> sender is notified if there is a delay delivering their message.

Hmmm indeed, hadn't even thought of that yet. This will complicate the
matter as DSN for undeliverable / delayed messages should be allowed but
not 'Your message has been successfully delivered to' or 'Your message has
been read by XX on XX' or 'Your message to XX was being deleted without
being read bla bla'.

A very annoying sideeffect of these DSN messages is that spam very often
uses the DSN feature to check on the addresses or to harvest more e-mail
adresses to send more spam. The e-mail adresses intended only for internal
use now also get spammed or when a message is adressed to a mailinglist
all members happily make their e-mail adresses publicly available.

Would it be possible to make the text of these DSN messages a string that
can be included sort of in a 'virus messages to be silently dropped' way
if it isn't possible to mess about with the DSN status in the
message headers?
This way (in this case Exchange) would still generate these 3 types DSN's
but they would never get delivered :)

>
> >I have tried to make the modification in the Makefile of the SRPM but this
> >is not so easy either.
>
> Read the man page for rpmbuild (or just rpm if you haven't got rpmbuild).
> You can do a "rpm -bp" to expand all the source code into
> /usr/src/redhat/BUILD. Then go in and tweak the makefile as you need to,
> then "rpm -bi --short-circuit" which will do the compilation and
> installation without attempting to redo the "-bp" stage.
>
> >On Fri, 30 Aug 2002, Julian Field wrote:
> > >  From the Bat Book (O'Reilly sendmail book), if you rebuild sendmail with
> > > ENVDEF=   -DDSN=0
> > > in your Makefile, it should disable all DSN support.
> > >
> > > You will probably find your Makefile in one of the obj.* directories in the
> > > sendmail build tree. Build it once using the defaults (as that will also
> > > create the sendmail Makefile specific to your system), then tweak the
> > > Makefile and rebuild just the sendmail binary.
> > >
> > > At 10:48 30/08/2002, you wrote:
> > > >Hi!
> > > >
> > > >I am using a linux box which is connected to the internet as a relay
> > > >to/from an Exchange 2000 server.
> > > >
> > > >I would like to completely disable (block) all outgoing DSN (Read Receipt
> > > >and DSN messages (your message has been successfully delivered to blah
> > > >blah).
> > > >
> > > >Is there a way to reset the flags on the incoming e-mail to prevent
> > > >Exchange from sending these messages?
> > > >
> > > >I tried to disable this 'feature' in Exchange 2000 first but it doesn't
> > > >seem possible.
> > > >
> > > >Also I would like to disable to non-delivery messages. We have lots of ND
> > > >messages as a result of spam to invalid e-mail adresses.
> > > >
> > > >Thanks for any input given!
> > > >
> > > >Best regards,
> > > >Remco
>
> --
> Julian Field                Teaching Systems Manager
> jkf at ecs.soton.ac.uk         Dept. of Electronics & Computer Science
> Tel. 023 8059 2817          University of Southampton
>                              Southampton SO17 1BJ
>
>