E-mail structures are potentially arbitrarily complicated. Cryptographic protection standards like S/MIME and OpenPGP or PGP/MIME are often applicable to some elements of some messages.
Last year's "E-Fail" attacks made it clear that trying to provide normal users with cryptographic protections on piecemeal parts of an e-mail message is a recipe for disaster, both from an implementation perspective and a user experience perspective. I've argued in more detail at  about the need to treat cryptographic protections at the message level, rather than at the subpart level.  https://dkg.fifthhorseman.net/blog/e-mail-cryptography.html This series makes "notmuch show" track and emit message-wide cryptographic state, providing an interface that simple clients that use "notmuch show" can rely on for their UI and UX. It doesn't yet apply this layer to the emacs interface, because at the moment many users of the emacs interface are nerds who are as likely to understand the intricacies of MIME structure as anyone, and for the moment, just augmenting the notmuch show schemata in a sensible way is enough of a chunk to bite off. (though i'd be happy to review and support the use of this per-message cryptographic state in notmuch-emacs if/when this lands!) I'd appreciate any review and feedback! Regards, --dkg _______________________________________________ notmuch mailing list firstname.lastname@example.org https://notmuchmail.org/mailman/listinfo/notmuch