Thanks for the information. I have now made sure that the message is converted
to printed-quotable before DKIM signing.
That results in DKIM verification pass but the message now is limited to 76
character length and each line longer than 76 characters ends with a '=' and a
line break for the lest of the line.
What appropriate MIME heards and ESMTP attributes are expected to not violate
RFCs so that the 8bit message can pass the DKIM verification as well?
----------------------------------------
> Date: Thu, 19 Nov 2015 12:53:08 -0800
> Subject: Re: DKIM Signature fails
> From: yahoogro...@lazygranch.xyz
> To: postfix-users@postfix.org
>
> Ignore my comment. I was thinking s/mime. Sorry about that.
>
>
> Original Message
> From: Wietse Venema
> Sent: Thursday, November 19, 2015 12:33 PM
> To: Postfix users
> Reply To: Postfix users
> Subject: Re: DKIM Signature fails
>
> yahoogro...@lazygranch.xyz:
>> I get the body hash failure on plain text.
>
> To send 8bit mail, you must provide appropriate MIME headers and
> ESMTP attributes, otherwise you violate email RFCs, and there is
> no guarantee whatsoever.
>
> In addition, it is wise to convert 8bit mail to quoted-printable
> before signing it, unless you are 100% certain that all MTAs in
> the path announce support for 8BITMIME. Otherwise a MIME-compliant
> MTA will break your DKIM signatures.
>
> Wietse
