Hi Evgeniy, On 26.01.20 18:13, Evgeniy Berdnikov via Exim-users wrote: >> The original message did only contain: >> Subject, To, References, From, Message-ID, Date, MIME-Version, In-Reply-To, >> Content-Type, Content-Transfer-Encoding >> >> Those headers where not altered, however List-XXX-Headers where added and >> thus broke the initial signature (as these headers where included as).
> DKIM-compliant mailing list manager should add those headers to the top, > before DKIM signature. That is right, however often not the case. >> By checking more examples, I do not think that there is an generic approach >> to do this. > > Generic approach to verify original DKIM signature, drop if signature is > invalid, then strip out all DKIM headers. Then message may be modified > arbitrarily by mailing list manager. Finally, message can be signed again > (using DKIM key of this list) and forwarded to subscribers. I was looking for a way to do this already at sending time before the mailing list software is involved. Thanks for the RFC hints. Best regards, Thomas -- Thomas Freitag -- ## List details at https://lists.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
