On 2023-09-19 at 11:46:28 UTC-0400 (Tue, 19 Sep 2023 17:46:28 +0200) Alessandro Vesely via mailop <[email protected]> is rumored to have said:
Comparing the bounced message with the original, it turned out the angle brackets were removed from the From: address, which is legal since there was no display-name, but breaks signatures. Still no idea how that happened.
Removing brackets on addresses without display names is one of the things that Sendmail (in some common configurations...) does.
(A few years ago I was tasked with eliminating the DKIM signature damage being done in a custom milter chain that ultimately went through Sendmail delivery to local accounts (mbox or Maildir) or relayed via SMTP to GApps/MS365. Ultimately it required about a year of in-prod testing and iteratively creating a routine that reproduced all of the odd little Sendmail canonicalization/normalization quirks ahead of signing.)
-- Bill Cole [email protected] or [email protected] (AKA @grumpybozo and many *@billmail.scconsult.com addresses) Not Currently Available For Hire _______________________________________________ mailop mailing list [email protected] https://list.mailop.org/listinfo/mailop
