Thanks Wietse, I've been reading up and I'll start testing with the parameter allow_untrusted_routing and I'll let you know how I get on.
On Wed, Mar 24, 2021 at 12:44 PM Wietse Venema <wie...@porcupine.org> wrote: > Paul Fowler: > > Hi Jaroslaw, > > > > Yes I think your correct. > > > > Just some further into, if I add the sender's IP to mynetworks then it > will > > accept the email with a special character "!" in the local part. > > So it seems postfix can accept special characters, I'm just not sure how > to > > allow this for every sender. > > allow_untrusted_routing (default: no) > Forward mail with sender-specified routing > (user[@%!]remote[@%!]site) > from untrusted clients to destinations matching $relay_domains. > > By default, this feature is turned off. This closes a nasty open > relay > loophole where a backup MX host can be tricked into forwarding > junk > mail to a primary MX host which then spams it out to the world. > > This parameter also controls if non-local addresses with > sender-speci- > fied routing can match Postfix access tables. By default, > such > addresses cannot match Postfix access tables, because the > address is > ambiguous. > > Wietse >
