[Mimedefang] hiding email addresses on server

Lucas Albers admin at cs.montana.edu
Tue Dec 23 02:05:31 EST 2003

I recently subscribed to a public mailing list.
Within 15 minutes of my first posting I was bombarded with virus's and spam.
I set my reply to address to something like
email+mailing-list854u3y at mydomain.edu

So i knew the address had been harvested from my post to the mail list.
This made me angry, yet again, so I considered the following idea.

If you set a certain reply-to address in your header, mimedefang on
outgoing mail will rewrite your from address and reply address to an email
protected format.

I set my reply to address to:
albersl+debian-users at debian.lists.org+NOPUBLIC+5DAYEXPIRE@cs.montana.edu

So in the outgoing mail it looks at the reply-to address and realizes it
needs to rewrite it, for mail that is sent to that mailing list, only.

So it rewrites the address to:
debian-user.lists.debian.org-88AJFB at cs.montana.edu
and sets my reply to address to:
aabbEMAIL-PROTECTED88AJFB at cs.montana.edu

This is how it works,
The from address only works for mail sent from the mailing list. The reply
to address works for N numer of days from the first time it is published,
then it expires.

It only has to maintain a hash for valid email addresses and hash for
valid email addresses from certain mailing lists.

Have to make sure you don't have collistions.
How to handle if the mailing list moves to another machine.
How to handle mail that is cc-ed to you through the reply-to address?
Should accept....

Out on a limb again?

--Computer Science System Administrator
--Security Administrator,College of Engineering
--Montana State University-Bozeman,Montana

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