[exim] Re: Can Exim drop TCP connections instead of properly…

Top Page
Delete this message
Reply to this message
Author: Jeremy Harris
Date:  
To: exim-users
Subject: [exim] Re: Can Exim drop TCP connections instead of properly closing them?
On 23/07/2023 11:04, Paweł Zuzelski via Exim-users wrote:
> Is it possible for Exim to drop the TCP connection instead of properly
> rejecting the message? I don't see any option like that in ACLs.


No. Exim really operates at SMTP and TLS levels rather than TCP.

Also: if you did a proper close on the TCP connection (to release
resources at your end) this will inform the peer, letting them
release their resource. You are asking, effectively, for a
firewall-level action.

> For some connections (like obvious attempt to send spam or probing for
> open relays) I would like Exim to just drop the connection without ever
> properly closing it, so that the client wastes memory waiting for the
> time out.


Why not just delay, with the SMTP connection held open.
Spammers do tend to time out their ends pretty quickly;
unless you are a high-volume site the resource at your end is
not large.
--
Cheers,
Jeremy


--
## subscription configuration (requires account):
## https://lists.exim.org/mailman3/postorius/lists/exim-users.lists.exim.org/
## unsubscribe (doesn't require an account):
## exim-users-unsubscribe@???
## Exim details at http://www.exim.org/
## Please use the Wiki with this list - http://wiki.exim.org/