Re: [ietf-smtp] Stray <LF> in the middle of messages

John Levine <johnl@taugh.com> Sat, 06 June 2020 21:02 UTC

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Date: 6 Jun 2020 17:02:23 -0400
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From: "John Levine" <johnl@taugh.com>
To: ietf-smtp@ietf.org
Cc: paul@pscs.co.uk
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Subject: Re: [ietf-smtp] Stray <LF> in the middle of messages
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In article <4efb92cb-9657-15eb-11f5-b6057f691505@pscs.co.uk> you write:
> From personal experience - the mail server we publish *used* to treat 
>either LF or CRLF as a line ending. That stopped over 20 years ago 

I think that's the key observation. Back in ye olden days there might
have been real mail systems that send bare LF but I haven't seen one
in a long time.

I also agree with the observation that defects in the SMTP protocol
are a very reliable indicator that you're talking to spamware. That's
why after all these years greylisting is still fairly effective. About
40% of the hosts that I greylist never retry.

-- 
Regards,
John Levine, johnl@taugh.com, Primary Perpetrator of "The Internet for Dummies",
Please consider the environment before reading this e-mail. https://jl.ly