[Mailman-Users] How to accept mail from a single IP / DNS name only for a given list

[Adam McGreggor]

On Tue, Dec 30, 2008 at 02:10:45PM -0500, Emmett Perdue wrote:
> 1st, forgive me if this has been answered before. I have searched high  
> and low and can not find an answer to my question.
> 
> How can I setup a list so that mail can be accepted ONLY from 1 IP  
> address? As an example I have a list named abc at 123.com and it is setup  
> as an announce list only accepting mail from 1 user with an address of 
> bob at 123.com .  How can I set this list up so that even if the mail appears 
> to come  from bob at 123.com the email will post to the list ONLY if 
> bob at 123.com's  email came from bobspc.123.com which has an an IP address of 
> 123.456.789.246

Sounds like the sort of thing to be handled by an MTA rule/ACL.

(nb: §3 of http://www.rfc-editor.org/rfc/rfc2606.txt)