On Tue, Jul 06, 2021 at 12:56:50PM +0200, Xavier Beaudouin wrote:
> I currently have an appliance that misuse the null sender (mail
> from:<>) to send mail.
>
> Unfortunatly, this appliance is closed source
> and we can only setup : fixed ip address and recipient address on GUI
> (nothing else, even if I try to h4x0r the configuration file).
>
> Is there any good advice I can have to make the internal relay server
> which is postfix based to rewrite the null sender to something
> cleaner... but ONLY for the device that use postfix as internal relay
> server?
This requires a content filter or milter, that replaces the envelope
sender address for messages from the client IP address in question.
There is no built-in feature that performs sender address rewrites
conditional on the client IP address.
The milter should be easy to implement.
--
Viktor.
