ietf-smtp
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Re: Bounce/System Notification Address Verification

2005-06-29 23:11:23

From: "Claus Assmann" <ietf-smtp(_at_)esmtp(_dot_)org>

On Tue, Jun 28, 2005, Claus Assmann wrote:

On Tue, Jun 28, 2005, Hector Santos wrote:

20040311 14:35:45 C: MAIL FROM: <>
20040311 14:35:46 S: 250 2.5.0 Address Ok.
20040311 14:35:46 C: RCPT TO: 
<r(_dot_)e(_dot_)sonneveld(_at_)sonnection(_dot_)nl>

Why does your system send a space after the colon?

Is this not worth an answer?

Sorry, I started it, put in my draft folder but forgot to get back to it.

I thougt you were talking about the above sonnection.nl host  as an
explanation or reason for the CBV failure at Rolf's site.  I checked that
and it was fine.  It didn't fail with the space.

Let's see whether your CBV still does that.

It seems it does: the direct mail was not accepted:

Recipient: <hsantos(_at_)santronics(_dot_)com>
Remote-MTA: 208.247.131.9
Reason: 550 Return Path not verifiable.

Well, the return path is just working fine (even sourceforge
with its callback has no problem with it).

I see now you were talking about your own SendMail server at esmtp.org.

AFIK, no server freaks out with the space. But nonetheless, it is not
consistent with the 2821 RCPT TO ABNF.   I already updated our CBV for the
next update. Thanks for pointing it out.

Let me get your logs... for this address of yours?  
ietf-smtp(_at_)esmtp(_dot_)org  ???
The only thing I found for esmtp.org domain was this following log which is
our WCSAP processor run from WCSMTP:

20050629 00:08:53 version    : 2.01 / 1.62
20050629 00:08:53 calltype   : SMTP
20050629 00:08:53 state      : rcpt
20050629 00:08:53 cip        : 63.195.85.27
20050629 00:08:53 cdn        : zardoc.esmtp.org
20050629 00:08:53 from       : <ca+envelope(_at_)esmtp(_dot_)org>
20050629 00:08:53 rcpt       : <hsantos(_at_)santronics(_dot_)com>
20050629 00:08:53 testorder  : FLT RBL SPF CEP CBV
20050629 00:08:54 sapfilter  : pass (time:78)
20050629 00:08:54 saprbl     : testing 27.85.195.63.sbl.spamhaus.org
20050629 00:08:54 saprbl     : testing 27.85.195.63.list.dsbl.org
20050629 00:08:54 saprbl     : testing 27.85.195.63.bl.spamcop.net
20050629 00:08:54 saprbl     : pass (time:266)
20050629 00:08:54 sapspf     : none (time:141)
20050629 00:08:54 sapcep     : test from=esmtp.org
20050629 00:08:54 sapcep     : test cdn=zardoc.esmtp.org
20050629 00:08:54 sapcep     : none (time:187)
20050629 00:08:54 sapcbv     : total mx records: 1
20050629 00:08:54 try mx     : zardoc.esmtp.org ip: 63.195.85.27
20050629 00:08:54 # connecting to 63.195.85.27
20050629 00:08:55 S: 220 zardoc.esmtp.org ESMTP sendmail X.0.0.Alpha4.0
20050629 00:08:55 C: NOOP WCSAP v2.01 Wildcat! Sender
                                Authentication Protocol
http://www.santronics.com
20050629 00:08:55 S: 250 2.0.0 Ok.
20050629 00:08:55 C: HELO mail.winserver.com
20050629 00:08:55 S: 250 zardoc.esmtp.org Hi there
20050629 00:08:55 C: MAIL FROM: <>
20050629 00:08:55 S: 501 5.1.7 Bad sender's mailbox address syntax.
20050629 00:08:55 sapcbv     : 501
20050629 00:08:55 result     : reject (0)
20050629 00:08:55 smtp code  : 550
20050629 00:08:55 reason     : Rejected by WCSAP CBV

If this session is yours, then it was CBV rejected due not honoring a NULL
mail from:

But the reason according to your server is the space in the MAIL FROM: <>
command as a syntax error.

Ok, wow!!!

You better reconsider being more relaxed with that MAIL FROM: strict syntax
I'm sure you will get hit by other servers

Unless you are saying this should be 100% honored and used for rejection?

I just ran a grep on May 2005 logs for incoming sessions looking for similar
syntax.

Out of 132,636 incoming transactions,  35360 transactions had a

            "MAIL FROM:sp<address>"

format.

Definitely use the standard for outgoing.   But parsing the space in
incoming messages is critical otherwise you will really get a lot of
rejections based on this.

Here are just three different servers out that accept the space.  You are
the first server that had this strict syntax problem.

Comcast.net

220 foon.sendmail.com ESMTP Sendmail Switch-3.1.7/Switch-3.1.7; Wed, 29 Jun
2005
 23:01:41 -0700
helo hdev1
250 foon.sendmail.com Hello adsl-10-44-25.mia.bellsouth.net [65.10.44.25],
pleas
ed to meet you
mail from: <>
250 2.1.0 <>... Sender ok

Sendmail.Com

220 sccrmxc16.comcast.net - Maillennium ESMTP/MULTIBOX sccrmxc16 #206
helo hdev1
250 sccrmxc16.comcast.net
mail from: <>
250 ok

Tony's EXIM machine

220-ppsw-0.csi.cam.ac.uk (mx.cam.ac.uk [131.111.8.140]:25) ESMTP Exim
4.51+ppsw+
3 Thu, 30 Jun 2005 07:03:15 +0100
220 This is the Electronic Mail Service of the Chancellor, Masters, and
Scholars
 of the University of Cambridge
helo hdev1
250 ppsw-0.csi.cam.ac.uk Hello adsl-10-44-25.mia.bellsouth.net [65.10.44.25]
mail from: <>
250 OK

--
Hector Santos, Santronics Software, Inc.
http://www.santronics.com






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