Milter-greylist

Hello,

I work for Universitat Pompeu Fabra, a medium size university from 
Barcelona. We have been using milter-greylist for more than a year with 
a great success, eliminating about the 80% of the incoming spam. Thank 
you guys!

One of the features we miss is the ability to control the amount  of  
messages that users and pc's from our network can send each day, because 
sometimes compromised accounts or virus-infected machines send spam 
through our mail servers. We have been evaluating Policyd [1] for 
message accounting, but it's seems a waste of resources to store again 
the traffic information as we already have it in milter-greylist.

The syntax in greylist.conf could be something like this:

# Each "normal-user" can only send e-mails to 1000 destinations each day
# and the sum of all the messages cannot be over 500MB
racl greylist from list "normal-user" accounting period 24h 
message-count-limit 1000 message-size-limit 500MB msg "Daily limit 
exceeded"

# Each "normal-pc" can only send 200 e-mails/hour. When it reach the limit
# we ask to send later until the beginning of the next period.
racl greylist list "normal-pc" accounting period 1h message-count-limit 
200 msg "Hourly limit reached. Try later"

# Each machine coming from a "problematic-domain" can only send 10 
e-mails/hour.
# When it reach the limit we ask to send later until the beginning of 
the next period.
racl greylist list "problematic-domains" accounting period 1h 
message-count-limit 10

What do you think?

Regards,
Jorge

[1] 
http://www.policyd.org/tiki-index.php?page=Accounting&structure=Documentation