[NTLUG:Discuss] mail server ... general question ...

[Fred James]

(general question because I don't know enough specifics yet)

The question is dropping incoming mail that does not have at least one 
recipient listed who's domain matches one in a list of domains.

The assumption is that the mail server software lacks any feature that 
would provide this capability.

The only two approaches I have been able to think of:
(1) Server receives mail and calls a program/script to validate the 
domain, waiting for a drop/pass return value.
     (a) Seems an unlikely approach without extensive modifications to 
the mail server software.
(2) Filter the incoming data stream, before it reaches the mail server 
software, dropping all invalid messages.

Does that sound right so far?

Actually, what we seem to be dealing with is a denial of service attack 
followed by, or couple with, the remailing of spam.

Sorry I cannot be more specific just yet - that's all the details I have 
so far - do they sound right, do you think?

Thanks in advance to anyone who would care to share any insight(s) on 
this kind of thing.


-- 
...make every program a filter...