Path: utzoo!censor!geac!torsqnt!news-server.csri.toronto.edu!cs.utexas.edu!uunet!zaphod.mps.ohio-state.edu!julius.cs.uiuc.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: <1990Dec17.183615.3887@mp.cs.niu.edu> Date: 17 Dec 90 18:36:15 GMT References: <2766B2E7.276@tct.uucp> <1990Dec13.131236.25304@mp.cs.niu.edu> <1990Dec16.203543.22769@chinet.chi.il.us> Organization: Northern Illinois University Lines: 72 In article <1990Dec16.203543.22769@chinet.chi.il.us> les@chinet.chi.il.us (Leslie Mikesell) writes: >In article <1990Dec13.131236.25304@mp.cs.niu.edu> rickert@mp.cs.niu.edu (Neil Rickert) writes: > >> 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. > >I don't think I follow this. Can you give a real example? Do you For example, you have the Internet name 'chinet.chi.il.us' and the UUCP name of 'chinet'. Your system is prbably set up well enough to recognize both names as local. But not all systems are. Suppose you didn't recognize 'chinet.chi.il.us' as local. Then if I leave 'To: les@chinet.chi.il.us' on the header, and you reply to all header addresses, your mailer wouldn't recognize the address as local so would send it back to a relay for reinterpretation. If you were a UUCP neighbor of mine, I would automatically rewrite 'chinet.chi.il.us' as 'chinet.UUCP' on all header destined for you, until I was sure you could properly recognize the address as local. >If headers aren't munged, you will never see a From: uucpsite!user. The Maybe that's true from your site, but not from others. >sending site would just use a local form (if any). As long as you >can resolve the replies coming back through you, I see no problem with >munging to user%site@your.domain but it would be a lot nicer if someone I sure hope they have changed it by now. But the last time I tried, mail addressed to user%site bounced with host unknown, while mail addressed to site!user went though. The site was not 'chinet', but it was bounced by either 'oddjob' or 'gargoyle', which are forwarders for your domain. >had thought about inverting the mappings before the standards were written. >At least it's better than path!user@your.domain which is almost certain >to be munged and/or interpreted incorrectly if it is forwarded off the >internet (incorrectly isn't quite the right word since that type of address >doesn't have a defined meaning outside of SMTP, but if I hand it to a program >named "rmail" on a uucp machne, I wouldn't expect it to look past the first >"!".) Hey, we agree. I wouldn't send 'path!user@my.domain' via rmail unless I knew that it would work for that host. I might send 'path!user', or 'myuucpname!path!user', but I don't mix '@' and '!' in an address using UUCP transport unless I have verified that they will be recognized correctly by the receiving domain. -------------- Actually, if 'chinet' were a UUCP neighbor, and sent mail for me to relay to Internet, I would rewrite 'From: les@chinet.UUCP' as one of 'From: chinet!les@mp.cs.niu.edu', or 'From: les%chinet.UUCP@mp.cs.niu.edu' or 'From: les%chinet@mp.cs.niu.edu'. But it would be my choice, not yours. (I believe I am currently using the second of these forms). However, since 'chinet' is not my UUCP neighbor, I rewrite 'From: les@chinet.UUCP' as 'From: les@chinet.UUCP'. The difference is that for my UUCP neighbors I have an obligation of making their addresses useable by Internet hosts, and of providing a route back to them. But for a UUCP address which is not a neighbor, I have no such obligation to provide a return route. -- =*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*= Neil W. Rickert, Computer Science Northern Illinois Univ. DeKalb, IL 60115 +1-815-753-6940