[Mimedefang] Adding support for learning our addresses

[Philip Prindeville]

David F. Skoll wrote:

>>One other thing I thought about: what about detecting spammers, and
>>then looking up the CIDR block that their address belongs to, and adding
>>it to a blacklist automatically in filter_relay()?
>>    
>>
>
>Too many false-positives.  We own a measly 8 IP addresses where our
>colo box sits.  If you block us because someone on our class C was bad,
>that's unfair.
>  
>

Ok, how about this proposal:

Rather than blocking the entire network (CIDR block) automatically, at 
least blacklisting
the individual address for 3-5 days?

I see a lot of cases where I'll reject email from ratware, and then 20 
minutes or an hour
or a day later, they reconnect and try to send it again (I'm sending 
them a 5xx and not a
45x response, too).

-Philip