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Re: [Ietf-dkim] Question about lone CR / LF

John R Levine <johnl@taugh.com> Sat, 03 February 2024 22:10 UTC

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Date: Sat, 03 Feb 2024 17:10:03 -0500
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From: John R Levine <johnl@taugh.com>
To: "Murray S. Kucherawy" <superuser@gmail.com>
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Subject: Re: [Ietf-dkim] Question about lone CR / LF
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>> Unix MTAs strip out the CR in CRLF, often on the way in, so by the time
>> opendkim sees the message, the line endings are just LF.
>
> That might be true when it's handing a message to an LDA, but it's not true
> for SMTP ingress filters.  For milter, CRs are preserved in the body, so
> opendkim sees exactly what came in over the wire.
>
> https://pythonhosted.org/pymilter/milter_api/xxfi_body.html

It's probably more of an issue on the way out.  On my system all the DKIM 
and ARC signatures are applied before the message is handed to the MTA, 
and it's all \n line endings.

Regards,
John Levine, johnl@taugh.com, Taughannock Networks, Trumansburg NY
Please consider the environment before reading this e-mail. https://jl.ly

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