Restrict sending to one address from one IP?

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Restrict sending to one address from one IP?
\ Kenton Brede (29 May 2007)
. \ Noel Jones (29 May 2007)

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Subject:	Restrict sending to one address from one IP?
Group:	Postfix-users
From:	Kenton Brede
Date:	29 May 2007

I've got this situation in which I need to set up an address for
announcements. What I've done is create a Mailman list and set it to
only allow messages to notes sent from
daily. daily is actually an alias
set up in /etc/aliases pointed to /dev/null and is the return address.
I have postfix set up so that it will only receive mail for user
aliases in virtual_alias_maps. Also "mynetworks =
/etc/postfix/access" contains the machines that are allowed relay
access on our network.

The above setup prevents anyone outside our network, and not
explicitly allowed to relay, from sending messages to
notes. But the machines allowed relay privileges in
/etc/postfix/access, can spoof the sender as daily,
and send mail to notes.

Is it possible to restrict machines which are allowed to relay on our
network from sending to notes?

In short if I could restrict sending to notes from
the server itself, and allow no other machines period, it would be
great.
Thanks,
Kent