Re: [Exim] Administrivia: Stop sending EICAR test strings

--On Monday, September 15, 2003 11:15:43 +0200 Giuliano Gavazzi
<eximlists@???> wrote:

>> Sorry, but my customers don't consider that to be useless at all.
>> Even those with dial-up links.
>
> Maybe my remark was not clear enough, but I do not doubt that your
> customers find it useful. Just that it is useful for *incoming* email, it
> is pointless for *outgoing* email.

But some of my customers have addresses on my server that are just
aliased to addresses at their primary ISP. The headers are still
quite usefull for them in that circumstance. Useful enough to keep
me from investigating ways to distinquish when an 'outgoing' message
is really leaving my servers and when it is looping back through
for some reason.

> I think there has been at least one post in the past reminding that it is
> possible to suppress these headers for outgoing only emails. I am not
> sure if this is doable for multiple recipients, where some are internal
> and some are not, but this is not really important, as long as you tag
> only emails that are coming from a non "local" source (where I include
> authenticated and relay-from sources).

I considered that; but I've found that some people actually like to
Bcc: themselves so that they can check the spam score on their outgoing
message to reduce the chance of accidentally causing a false positive
at their recipient's site.


> I do not understand what you mean, why would the message make its way
> back to your server unchanged?

Mailing list managers configured to not add headers or footers to
the body. Aliases that point from one domain to another (each with
its own server.)

>> If your ISP doesn't offer any sort of filtering, then you should ask
>> them why not; and consider changing ISPs. Or look for someone who
>> can provide you mail exchanger service that you can customize to your
>> own needs.
>
> If that was the case I would not be subscribed to this list, would I?

Not necessarily. You might be using Exim at work but have no direct
control over the MTA your dial-up uses at home.

> I use dialup to access *my* mail server only when I am off-site, and when
> this happens I usually cannot control all my lists subscription addresses
> thanks to the extra load due to excessive quoted text, extra and useless
> headers...

The only thing that can be done about excessive quoted text is attempt
to educate users. Headers you don't like can easily be deleted in your
mail server. (Or, better yet for your purposes, delete everything
except the headers you like.)

If you are using IMAP (and if I remember the IMAP spec right), it
should be possible for a MUA to only download those headers that it
actually wants to display; even when downloading the entire body to
be read. (There's no reason why an MUA would need to download the
Recieved: or Message-Id: headers unless you've asked to 'view all
headers'. The same probably applies to Envelope-to: and Return-path:
If it isn't doing reference-based threading, it could delay downloading
the References: and In-Reply-To: headers until you start to compose
a reply.)

I have no idea whether any existing MUAs work that way or not; but
it's an interesting idea for thin-pipe applications. (I would think
it would also be appreciated by users of handhelds and PDAs with
mail access.) I do know that better MUAs only download the specific
attachments that you ask to view - this includes only getting one
of the forms when multipart/alternative is used. (I.e., Given a
message with both text/plain and text/html, it will only download
the one that it is set to display by default; unless you explicitly
ask to see the other.)

> Anyway, I think I can get rid of those headers with headers remove (I
> will have a look at the docs) although I am not so keen in modifying
> incoming email.

Yes, you can. Quite easily if you have a list of headers you want
removed. I think you need a system or personal filter if you want
a header whitelist instead of a header blacklist.

If you're using Cyrus, I think you can do header removal in a Sieve
script; which would let you personalize it a bit more and make it
conditional on other factors if you like. Actually, you should
be able to do the same things with a personal Exim filter. I just
tend not to think about them since I deal mostly with virtual users
who only have mailbox access. (And since I'm using Cyrus with Sieve.)



-Pat