gnu@sun.uucp (John Gilmore) (02/24/84)
From: eric%ucbarpa@Berkeley.ARPA (Eric Allman) Subject: Re: "Return-Path" vs. "From" Gosh Chris, I'm awfully sorry that I have tried to do the right thing instead of perpetuating the insanity that has characterized (and sadly, continues to characterize) the UNIX mail system. Sendmail passes the information it gets from the received envelope into the transmitted envelope. If the mailer is a program rather than an SMTP channel, the "envelope" consists of the command line arguments. Unfortunately the information provided by uucp in the "envelope" is often wrong. This causes the "From " line and the "From:" line to differ, which is very confusing to the end-users, mail-readers, etc. For mail generated on the Arpanet and relayed to Sun via uucp, the From: line is right (or at least can be munged to be right, by adding ".arpa"), but the "From " line often claims the message is from "daemon" or "uucp" or whatever user happened to do something that started this uucp connection. E.g.: From uucp Thu Feb 23 00:27:47 1984 From: Ed Pattermann <PATTERMANN@SUMEX-AIM.ARPA> To: "sun!gnu@shasta"@SUMEX-AIM.ARPA For mail which has been passed solely thru uucp sites, the "From " line is clearly correct, since the "From:" line has not been maintained at (all) intermediate sites. E.g.: From dual!allegra!cbosgd!fair Thu Feb 23 17:01:34 1984 From: dual!cbosgd!fair The win would have been to make the envelope right for all uucp traffic, (which it already was for strictly-uucp traffic) and have sendmail fix the From: line to match the "From " line. This has not been done -- yet. Is there a uucp/mail expert in the house who can tell us WHY the envelope is "uucp" or some user, instead of the right thing?
fair@ucbvax.UUCP (Erik E. Fair) (02/26/84)
Uh, I have a small nit to pick with John Gilmore. The example he used for showing the proper interpretation of `correct' mail headers from the UUCP land was wrong: >>For mail which has been passed solely thru uucp sites, the "From " line >>is clearly correct, since the "From:" line has not been maintained at >>(all) intermediate sites. E.g.: >> From dual!allegra!cbosgd!fair Thu Feb 23 17:01:34 1984 >> From: dual!cbosgd!fair >> >>The win would have been to make the envelope right for all uucp >>traffic, (which it already was for strictly-uucp traffic) and have >>sendmail fix the From: line to match the "From " line. This has not >>been done -- yet. Is there a uucp/mail expert in the house who can tell >>us WHY the envelope is "uucp" or some user, instead of the right thing? I have been many things in my time, but never have I been cbosgd!fair. I'm dual!fair or ucbvax!fair or fair@ucb-arpa.ARPA. The problem is that some 4.2 BSD sites out there are running bogus versions of sendmail which puts out the return address in the envelope in domain format. It gets worse when the letter passes through a working sendmail sites, because they try and undo the damage, and only succeed in hiding it. That letter there started life From dual!fair cbosgd changed that to From cbosgd!fair@dual.UUCP and allegra changed that to From dual!allegra!cbosgd!fair It gets really fun when someone tries to reply to that. This bug has been fixed by steve@nbires.UUCP, tjt@masscomp.UUCP, postmaster@uwisc-rsch.ARPA, and eric@BERKELEY.ARPA Some by my prodding them, some not. If you spot one of these, complain until it gets fixed, because all mail passing through the suspect site will have bogus return addreses, and only the silly people who keep the entire routing map in their heads (like me) will be able to get anything through the Emails. (Mark Horton, are you listening? Do I have to beat this to death?) Please, Help Stamp Out Sendmail Errors by sending your tax deductible contributions to Save the Network Box 10.2.0.78 Berkeley, California 94720 Thank you. Erik E. Fair ucbvax!fair fair@ucb-arpa.ARPA P.S. For those on USENET: 10.2.0.78 is ucbvax's ARPANET address. :-)
chris@umcp-cs.UUCP (02/27/84)
Well, on our system the uucp "envelope" info is usually wrong
because uux uses getpwuid(getuid())->pw_name, but it is invoked
on behalf of the fake user "mmdf" when MMDF dequeues UUCP channel
mail.
--
In-Real-Life: Chris Torek, Univ of MD Comp Sci
UUCP: {seismo,allegra,brl-bmd}!umcp-cs!chris
CSNet: chris@umcp-cs ARPA: chris.umcp-cs@CSNet-Relaytjt@kobold.UUCP (02/27/84)
For anyone who is interested:
I fixed the sendmail bug described by Erik Fair (sending out domain
based address in the unix-style "From " line) by switching from the
4.1c version of sendmail to the 4.2 version. Looking at the Version.c
file indicated that this was explicitly fixed and is not an artifact of
an aberrant configuration file.
--
Tom Teixeira, Massachusetts Computer Corporation. Westford MA
...!{ihnp4,harpo,decvax}!masscomp!tjt (617) 692-6200 x275gjm@ihnp4.UUCP (Gary J. Murakami) (02/28/84)
Last time I looked at cbosgd's config file, my analysis agreed with Erik Fair's analysis of the situation. Empirical evidence seems to point out that the path reversal problem still exists at more than one host. Part of the problem stems from the inconsistent treatment of a!b@c. Unfortunately the 4.2 distribution contains config files that do a considerable amount of header munging, and more hacking will probably make matters worse. Sendmail is still a mixed blessing, however some of us hope to eventually fix the (few) cursed parts. Gary Murakami AT&T Bell Laboratories ihnp4!gjm
tjt@kobold.UUCP (02/29/84)
Although I missed Rob Pike's "cat -v considered harmful" talk at the
Toronto USENIX conference, I understood he mentioned that the current
trend in arcane command switches would no double lead to an extension
language for cat. It occurred to me the other day after wrestling with
configuration files that sendmail must be the aforementioned extension
language (where is TECO now that we need you?).
--
Tom Teixeira, Massachusetts Computer Corporation. Westford MA
...!{ihnp4,harpo,decvax}!masscomp!tjt (617) 692-6200 x275