sendmail access control

[Paul Howarth]

Justin Zygmont wrote:
> I was wondering if anyone that knows sendmail well enough to say if 
> something like this can work?
> 
> /etc/mail/access
> 
> 192.168.0.1        RELAY
> 192.168.0.2        RELAY
> 192.168.0.0/24        REJECT

Sendmail doesn't understand CIDR format in the access file. You'd need 
to use:

192.168.0	REJECT

> as it implies, I want to allow only certain hosts to send outgoing 
> email, while rejecting all others, even if authentication is used.  
> However internal email should still be allowed.
> 
> Is there a way to do it?

How would you propose to distinguish between "internal" and "outgoing" mail?

The easiest way of doing this is probably to run two mail servers, one 
handling only internal mail, accessible to all, and one capable of 
outgoing mail, available only to the selected few.

Paul.