Re: ezmlm and BATV

Bruce Guenter <[email protected]> writes:

> On Wed, Aug 01, 2007 at 03:15:18PM -0700, John Keith wrote:

>> I believe the BATV part of this discussion pertains to subscriber-only
>> (or variants of such) lists.  These lists try to match the envelope
>> sender address to a valid list subscriber, but that doesn't work if the
>> envelope sender is modified to something such as:
>> 
>>     [email protected]

>
> Which BATV are you referring to?

Hi Bruce,

Thanks for your reply.  

Here's one link I found:
http://tools.ietf.org/html/draft-levine-mass-batv-00

The ezmlm generation of envelope senders isn't an issue here -- I'm
talking about the envelope sender that arrives with the original
message when sent to the mlm.  

Here's what's happening: 

A subscriber joins a list with email address [email protected].  The
list is configured with -u, so that list posting is restricted to
subscribers to the list.  So far, so good.  We run thousands of lists
such as this (thanks to ezmlm!).

On the subscriber's side, they are constantly generating variants of
their email address (see above) that encode their original email address
with some unique hash-based information.  I believe the idea is to
automate bounce handling on their end (I don't use it, so I can't say
for sure).  But it makes some sense.

When this user decides to post a message to the list, ezmlm looks at the
envelope sender, [email protected], and rejects the
posting because that address does not exist in the subscriber list.  The
local part of the address has been modified (though the address is in
there somwhere).  The address is periodically and/or randomly
regenerated, so adding them to the allow list doesn't do the trick
either.

These users are insisting that we update ezmlm to either de-munge the
incoming envelope sender or to have ezmlm use the message "From" header
instead of the envelope sender when validating posting rights against
the subscriber list.

So I guess my question is: are we the only people receiving such
complaints?  We probably have about 200,000 subscribers across our list
base, which means there are bound to be a few BATV users in there.  This
may become more prevalent, which is one reason why I thought others on
this ezmlm list might know something or care about the outcome.


          - John