Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!lll-lcc!styx!ptsfa!vixie!paul From: paul@vixie.UUCP (Paul Vixie Esq) Newsgroups: comp.mail.misc,comp.mail.uucp Subject: Re: whether to prefix myhost! onto the From: or not.. Message-ID: <610@vixie.UUCP> Date: Thu, 30-Apr-87 03:09:51 EDT Article-I.D.: vixie.610 Posted: Thu Apr 30 03:09:51 1987 Date-Received: Sat, 2-May-87 06:31:22 EDT References: <604@vixie.UUCP> <4323@auspyr.UUCP> <606@vixie.UUCP> <608@vixie.UUCP> <1596@munnari.oz> Reply-To: paul@vixie.UUCP (Paul Vixie Esq) Organization: Vixie Enterprises, San Francisco Lines: 72 Xref: mnetor comp.mail.misc:245 comp.mail.uucp:516 In article <1596@munnari.oz> kre@munnari.oz (Robert Elz) writes: >But those addresses are always "user@host...domain" where domain is one >of the legal top level domains, and most certainly "UUCP" isn't one >of them. Worse, .UUCP is used inside a lot of sendmail.cf as the "mock domain" for UUCP traffic. .UUX is the newer method, but many .UUCP .cf's still exist. Beware! (Said paul@vixie.UUCP... ugh...) >For addresses in "host!host!...!user" form, in the From_ or From: line, >you *must* add your own hostname, as that's all that makes the >address sensible. Wait, wait. If I get mail with a From: line whose content is "a!b!c", then (according to the RFCs) the mail came from a user ON MY MACHINE who likes to log in as "a!b!c". Assuming that it came from "a" who talks to "b" who in turn has a user who logs in as "c" is charitable, though often also self- serving. I begin to wonder if it wouldn't be better to rewrite into c@b ? No, that won't work -- unless "b" is a known domain name. Anything you do with "a!b!c" is optional, non-standard, and likely to work spasmodically -- if at all. As I said in another article, the path may be "a!b!d!e" and be WRONG because "c" did the right thing. Now, the From_ line, on the other hand, Usually Has The Right Path In It. This is because it's Supposed To Have A Path In It, Not An Address Like The From: Line. If your mail user-agent insists on using From:, either make your transport agent able to understand domains, or change your user agent to make it reply to From_ addresses. If you don't have source, get smail, or write some simple shell scripts, or complain to your vendor, or don't use reply (type the address yourself). >[...] your own host, >which is the only uucp name that you can be certain of by itself. To be fair, I can usually be certain of my immediate UUCP neighbors also. >[...] ones who have been misguided by those who believe (rightly) that >domains are the only way this mess can survive, but who have gotten >ahead of themselves and assumed that anything can be made a domain >at random. Several interpretations here: if "anything" means a forwarding host, then you have a valid complaint. Suddenly assuming that all addresses will be in domain-format is foolish -- like I said, though, the From_ line is there.. If by "anything" you mean some ADDRESS being processed, you still have a valid complaint. Rewriting addresses is evil, even if you are correcting a bang-path to look like a domain. Better to send it back undeliverable... >So, if you find a legal domain name, leave it alone. I agree. >If you don't then the address should be kept in old style uucp format, >and the local host name should be added. I disagree -- send it back, undeliverable. >At least people who route their >mail through rational hosts will have it work. This puts quite a load on the word "rational". I'd say that with the coming onslaught of X.400 (when all the HP and IBM and other computers in the world suddenly join the Internet), we'd better get cracking on making domains work. We don't have 15 years to get thing into shape -- we have about two. Maybe three. -- Paul A. Vixie {ptsfa, crash, winfree}!vixie!paul 329 Noe Street dual!ptsfa!vixie!paul@ucbvax.Berkeley.EDU San Francisco CA 94116 paul@vixie.UUCP (415) 864-7013