Can pf block illegal relay access attempts?

[Ladislav Bodnar]

On Friday 17 December 2004 14:14, Pyun YongHyeon wrote:
> On Fri, Dec 17, 2004 at 01:56:34PM +0800, Ladislav Bodnar wrote:
>  > Hi,
>  >
>  > Over the last 7 days my Postfix mail server received almost 80,000
>  > requests to relay mail to a third destination. Since it is not an open
>  > relay, it rejected all these requests, but it is still annoying to see
>  > this happening. The requests came from varying (almost 20,000
>  > different) IP addresses, but they had one thing in common - the
>  > destination address was always "$some-user-name"@infomagic.com.
>  >
>  > Is there a way to prevent these attempts to access the mail server at
>  > all? I only started using pf recently, so I still have a lot to learn,
>  > but I would appreciate any advice. Or is pf not the right tool for
>  > this?
>
> Try spamd in ports/mail.

Thank you for your suggestion.

I investigated spamd and found out that it blocks connections based on IP 
address only. Unfortunately, I generated almost 20,000 different IP 
addresses over the last 7 days, so I don't think the IP addresses I would 
block are valid. I am looking for a solution where a connection is refused 
based on the recipient's email address (which is always @infomagic.com). 

Basically I am wondering if pf can refused a connection based on some other 
criteria than IP address.

Thanks a lot.