Author: Phil Pennock Date: To: Charlie CC: Exim-users Subject: Re: [exim] Technique for preventing multiple email addresses being
used?
On 2009-11-08 at 13:15 +1100, Charlie wrote: > I am receiving SMTP traffic sent to me from many guests in hotel through
> automatic SMTP redirection.
> We have a system whereby the hotel is allowed to send 'From' up to 200
> different email addresses each day.
> This works fine for the most part.
> Sometimes, though, a problem occurs. Someone using the hotel's IP address
> sends out a single spam email from 200 different email 'From' addresses
> within the space of about 10 minutes. This uses up the hotel's entire quota.
> My question is this: does Exim have some sort of built-in mechanism that can
> cope with, say, limiting the number of different email addresses that are
> allowed to be used by a particular IP address, per time period (e.g. 1
> hour).
Yes.
> Or is that asking way too much?
No.
You're looking for the term "ratelimit". You can search The Exim
Specification for that word, to see a couple of approaches, including a
top-level ratelimiting which can be applied to certain hosts, or the
"ratelimit" ACL condition for more complex requirements.
