Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!newstop!sun!amdcad!dgcad!gary
From: gary@proa.sv.dg.com (Gary Bridgewater)
Newsgroups: comp.mail.uucp
Subject: Re: internet/uucp mail
Message-ID: <658804371.13790@proa.sv.dg.com>
Date: 17 Nov 90 01:12:51 GMT
References: <1990Nov15.033214.27771@beach.csulb.edu> <1990Nov15.205028.4567@beach.csulb.edu>
Organization: Data General SDD, Sunnyvale, CA
Lines: 44

In article <1990Nov15.205028.4567@beach.csulb.edu> ericp@beach.csulb.edu (Eric Pederson  CSE) writes:

>I found through experimenting that user%dest.uucp@bigcorp.com worked
>ok.  My only problem now is that mail I recieve from UUCP sites here
>have a From: header like dest!user@bigcorp.com, which if I try to 'r'eply
>to, give the uux 101 unknown mailer error again.

Of course it is no help to you, but, "bigcorp" has a broken .cf file if they
are abusing addresses like this.  Their outgoing "From:" address rewriter
should not be blindly appending their domain address - it should check to see if
the current addresses is in "!" form and, if so, either 1) leave it alone, or
2) PRE-pend their UUCP address if they have one.  This would leave the
address as replyable to.   Some number of sites do this awful thing - please
stop.

>Obviously my sendmail.cf is going to have to be modified.  Does anyone
>happen to have some sendmail rules that will handle
>uucpdest!user@knownhost.com by routing to knownhost.com first via SMTP?

Or you can just hand-type over the bogus address.
It's hard to answer your question without knowing what kind of an address
your site prefers.  Are you a UUCP only site or are you connected to the
backbone in some manner?  Is "knownhost" different from "bigcorp"? Did we
go from the pseudo-specific to the pseudo-generic?

A UUCP onlu site, when presented with uucpdest!user@knownhost.com address, has
to punt this to its smart upstream forwarder via smart!knownhost.com!uucpdest!user.

A site connected to the backbone via some intermediate host (like we are, via
relay.cs.net) needs to find out from their postmaster what sort of syntax works,
e.g. @connectedhost.com:knownhost.com!uucpdest!user. But ask the postmaster (of
connectedhost.com) since this is a somewhat religious thing.

Smarter hosts and MX based hosts should just be able to send the answer back to
bighost.com and let it worry about it since it generated it in the first place -
you could try rewriting it as @bighost.com:uucpdest!user or user%uucpdest@bighost.com
but that does not generalize to user%uucphop!uucpdest@bighost.com.

But the bottom line is - you should not be getting mail with ambiguous From:
addresses.  Hosts that act as gateways are required to generate consistent
addresses.
-- 
Gary Bridgewater, Data General Corporation, Sunnyvale California
gary@sv.dg.com or {amdahl,aeras,amdcad}!dgcad!gary
C++ - it's the right thing to do.