Path: utzoo!mnetor!tmsoft!torsqnt!news-server.csri.toronto.edu!rutgers!cs.utexas.edu!uunet!maverick.ksu.ksu.edu!ux1.cso.uiuc.edu!mp.cs.niu.edu!rickert
From: rickert@mp.cs.niu.edu (Neil Rickert)
Newsgroups: comp.mail.misc
Subject: Re: Which headers may Sendmail re-write?
Message-ID: <1990Dec18.152151.29598@mp.cs.niu.edu>
Date: 18 Dec 90 15:21:51 GMT
References: <2766B2E7.276@tct.uucp> <1990Dec13.131236.25304@mp.cs.niu.edu> <276D0D6A.6581@tct.uucp>
Organization: Northern Illinois University
Lines: 61

In article <276D0D6A.6581@tct.uucp> chip@tct.uucp (Chip Salzenberg) writes:
>According to rickert@mp.cs.niu.edu (Neil Rickert):
>>In article <2766B2E7.276@tct.uucp> chip@tct.uucp (Chip Salzenberg) writes:
>>>
>>>2.  A message passing through your domain on its way to my domain
>>>    should be left alone, without ANY modifications to the message
>>>    AT ALL except for the envelope.
>>>
>>
>>Sure.  And when I relay Internet mail to 'uucpnode', and a user on
>>'uucpnode' does a R(eply), my machine gets to relay a lot of the
>>uucpnode's local mail back to it, since that node doesn't understand
>>the form of address on the header so sends it to its forwarding relay
>>for interpretation.
>
>Assuming that the 'uucpnode' to which Mr. Rickert refers is a
>UUCP-only site that doesn't understand RFC822 addresses, then it is
>true by definition that an RFC822 address field will be unrepliable
>when it arrives at 'uucpnode.'
>
>However, the policy that Mr. Rickert supports -- pessimistically
>rewriting all mail headers for the greatest common denominator,
>namely, stock Unix /bin/mail -- disinfranchises all those UUCP sites
>who have registered domains under the Internet DNS.
>
 No where did you get the idea that I support "pessimistically rewriting
all mail headers for the greats common denominator"  -- I never said that,
and I don't practice that.  Just because I support the premise that at
times they should be rewritten, don't jump to the conclusion that I
always do so.  For example, I have a UUCP neighbor, with uucp name of
'earth'.  (This is NOT the earth.UUCP in the maps).  If you send mail to
say 'root@geol.niu.edu', and it arrives at my site with headers:
 To: root@geol.niu.edu
 From: chip@tct.uucp
then it will be forwarded to earth!root with exactly the same headers.
If, on the other hand, you address your message to 'root@earth.uucp'
and it reaches my site, it won't finish up at the geology department at
all - it will go the the 'earth.uucp' on the maps.

 Please don't jump to conclusions and put words in my mouth that I never said.

>Furthermore, 'uucpnode' may not be the final destination of the
>message.  It is not a good idea to assume anything about the final
>site based simply on the identity of the next hop in a bang path.
>
>I contend that rewriting "user@host.valid.domain" into
>"host.valid.domain!user" in the *header* is a Bad Thing because:
>
 If I see mail with a header address 'user@host.valid.domain', and I am
forwarding it to a host which does not understand RFC822 addresses, I WILL
rewrite that as 'host.valid.domain!user'.  The fact that uucpnode may not
be the final destination is AN IMPORTANT PART of the reason.  For 'uucpnode'
is very likely to blindly stick 'uucpnode!' in front of the address.  This
totally massacres the RFC822 format address, but does no serious harm to the
form changed into bang notation.

-- 
=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=
  Neil W. Rickert, Computer Science               <rickert@cs.niu.edu>
  Northern Illinois Univ.
  DeKalb, IL 60115                                   +1-815-753-6940