Re: [Exim] callout suggestion

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Author: Chris Edwards
Date:  
To: exim-users
Subject: Re: [Exim] callout suggestion
On Mon, 23 Feb 2004, Philip Hazel wrote:

| I have to confess to brain fade. I thought Exim already used the
| message's actual sender when doing recipient callouts. However, when I
| look at the code, I see that it does not. I have been under this
| delusion for quite some time...


I asked this back in May:

http://www.exim.org/pipermail/exim-users/Week-of-Mon-20030512/053733.html



And David Woodhouse wrote:

| If, for example, I do recipient verification callouts for mail from
| +relay_hosts, I'm going to refuse to allow my relay_hosts to relay mail
| to the Exim list, because the Exim list doesn't accept MAIL FROM:<>, and
| with good reason. There are plenty of other addresses which only
| _receive_ but never send email, which will quite reasonable reject MAIL
| FROM:<> at RCPT time.


ooh - I'd never thought recipient verification callouts would be used for
for mail from +relay_hosts (outgoing mail).

We use the facility (as Nigel described) on our gatekeeper MXs as a "cheat"
to get the user db for some internal domains - to avoid sending bogus
bounces to forged senders. This works well.

But in the case of +relay_hosts, surely you are quite entitled to send the
local user a bounce as you (hopefully) already know the return-path is
valid ?

I'm just curious as to what situations recipient callouts are useful...

Chris


--
Chris Edwards, Glasgow University Computing Service