Re: [exim] Defer mail for time

On 2008-12-24 at 11:05 +0200, Brent Clark wrote:
> Would anyone know how to defer mail from an address, but based on time
> of the day.
>
> Basically Ive been asked by management to defer all from gmail, facebook
> etc, between 8 and 5pm.

[ disclosure: I work for a company probably affected by this policy ]

So, there's a quandary here. Email is exchanged between consenting
systems operating under local rules. You're entitled to not accept
email which you don't want and nobody can say otherwise.

Yet email is built on cooperation and resources provided to others on
the basis of that cooperation.

Forcing mail to queue up on other peoples systems when it is legitimate
is basically using other people's disk-space, unpaid, to implement local
policy. That's abusive. You might ask for sign-off from your company's
legal counsel about the matter of deliberately consuming the resources
of others for purposes other than the purpose provided (storage for your
policy, instead of hand-off) without notice, recompense etc.

My non-lawyer understanding is that as an employee, you have a lot more
protection against legal issues if you have, in writing, a sign-off from
legal counsel; any issues then lay with management and the legal
counsel. Push-back in this manner may cause reconsideration and it
would never come to actually needing anything on paper -- carefully word
the issue and you'd never even need to ask for something on paper, once
legal counsel realise what's been asked for.

If you go ahead with this anyway, then please make sure that this defer
policy is in your ACLs *AFTER* all the checks which would normally lead
to rejection -- you should still send 5xx permanent failures, allowing
the remote site to discard mail or have their abuse systems get feedback
and maybe filter out some of the 4xx temp-failed messages. You should
be deferring *only* what would otherwise be accepted, not what would
otherwise be rejected. You can do this by putting the defer ACL clause
just before the final accept in the ACL.

Regards,
-Phil