Connection throttling POP3.

[David S. Madole]

> On Mon, 21 May 2007, Matthew Schumacher wrote:
>
>> List,
>>
>> And this spammer is racking up a zillion processes which 
is killing 
>> my machine.  I need a way to throttle this somehow where 
he is only 
>> allowed one connection per IP at a time, or perhaps a way 
to ignore 
>> them after so many invalid passwords.
>>
>> Anyone know of a way to do this?

If you are on Linux, you can do something like this, which I use for SSH for the same reasons:

iptables -A INPUT -p tcp --dport 22 \
         -m state --state NEW \
         -m recent --update --seconds 60 -j DROP

iptables -A INPUT -p tcp --dport 22 \
         -m state --state NEW \
         -m recent --set -j ACCEPT

This limits connections to once a minute.

David