david@ms.uky.edu (David Herron -- One of the vertebrae) (03/14/89)
Someone call the protocol police! Script started on Mon Mar 13 16:45:18 1989 You have mail. | 1 - s:david --> telnet wpafb-fdl.arpa smtp Trying... Connected to wpafb-fdl.arpa. Escape character is '^]'. 220 HYPER-LINK VAX/VMS Simple Mail Transfer Service ready. helo e.ms.uky.edu -----> 501 Syntax error in parameters or arguments. mail from:<david@ms.uky.edu> 250 Requested mail action okay, completed. rcpt to:<edwardsrl@wpafb-fdl.arpa> 250 Requested mail action okay, completed. data 354 Start mail input; end with <CRLF>.<CRLF>. From: david@ms.uky.edu To: edwardsrl@wpafl-fdl.arpa Subject: test I'm demonstrating to comp.protocols.tcp-ip that your mailer is broken. . 250 Requested mail action okay, completed. quit 221 HYPER-LINK VAX/VMS Service closing transmission channel. Connection closed by foreign host. | 2 - s:david --> script done on Mon Mar 13 16:47:07 1989 The marked line is in error. I just checked in RFC-821 to make certain and it says in section 4.1.1 that the HELO command and an affirmative reply are necessary to ensure that both mailers are in sync. Further in section 4.3 in the COMMAND-REPLY SEQUENCES, the only allowable "Success" reply is a "250", "501" is an "Error" reply. -- <-- David Herron; an MMDF guy <david@ms.uky.edu> <-- ska: David le casse\*' {rutgers,uunet}!ukma!david, david@UKMA.BITNET <-- <-- For a good time send mail to somebody@ms.uky.edu
brunner@CACFS.ARMY.MIL (Thomas Eric Brunner) (03/15/89)
David, Don't take this too seriously, the nic's smtp service, which advises that one not worry and be happy views an unargumentative "helo" similarly: 220-SRI-NIC.ARPA SMTP Service 6.1 at Tue, 14 Mar 89 08:52:36 PST 220 Don't Worry. helo 500 Missing required argument: helo as does, of course, a.isi.edu... For all I know this is a feature of TOPS-20, as both of these two hosts are DEC-20s running TOPS-20, and version 6.1 of their SMTP implementation, emulated on VMS hosts :-). Eric P.S. Ignore bogus return address, fixing mailer, use brunner@spam.istc.sri.com for best results
mrc@SUMEX-AIM.STANFORD.EDU (Mark Crispin) (03/16/89)
I wrote the TOPS-20 SMTP server. I think that ISI and GUNTER-ADAM run their own homebrew server, but all other 20's run mine. Some, such as the NIC, have hacked their servers; the "Don't Worry." was originally "Please report any problems to Bug-MAISER@WSMR-SIMTEL20.ARMY.MIL." ... At the time I wrote it (1982) I endeavored to make it conform to the standards as published in RFC-821. I also believed in thorough syntax checking. I was already warned that some Unix systems used a bogus form of A-D-L: <@foo:@bar:rag@zap> instead of the correct <@foo,@bar:rag@zap> and that many omitted the "@zap" part as well if "zap" .eq. server-host. I made allowances for these external bugs. However, I believed that this did not imply license for new SMTP clients to violate SMTP in other ways. So, I require a HELO before a MAIL, a MAIL before a RCPT, and a RCPT before a DATA. I also check the argument for the HELO, but no HELO is ever rejected unless the argument is missing (a client bug), syntactically bad (a client bug), or it the argument equals the local name and the connection isn't coming from the local host (a client and/or network "mirroring" bug, the latter being quite common in NCP days). My worst "crime" in all of this was my firm insistance that a NEWLINE that ended an SMTP command was a CR followed immediately by a LF. No bare CR's, bare LF's, LFCR's, CR NUL's, etc. etc. need apply. About once a month, I get a message from some guy *insisting* that my server is broken, and it turns out he's sending bare LF's for newlines because his sendmail.cf is broken. How do I feel today? I don't care. Nobody seems to care whether or not the protocols conform to specifications as long as they interoperate (which, I guess, is the bottom line) so everybody just makes allowances for the zillions of new bugs except for stubborn twerps like me who don't want to be bothered to remove all my own syntax checking code and just tell the guys "it's your bug, fix your client!!" Then, when things like an Internet Worm hit, we're unaffected and happily networking until they take down the net on us...... :-) -- Mark -- -------