On Thu, Sep 29, 2022 at 04:11:35PM +0000, Slavko via Exim-users wrote:
> RFC 6376, section 4.2:
>
> Signers SHOULD NOT remove any DKIM-Signature header fields from
> messages they are signing, even if they know that the signatures
> cannot be verified.
SHOULD NOT is not "MUST NOT". Especially if the signatures are one's
own from a prior internal SMTP relay hop. And there is RFC policy,
there are times even good reasons to ignore "MUST NOT".
The imperative terms in RFCs are about what is necessary to be sure
to interoperate. If one is willing to occasionally risk not being
able to interoperate, one can freely ignore all RFC requirements,
at one's own risk.
--
Viktor.
