Perhaps we should not be stripping attachments but encapsulating
the whole message with enough DKIM signed meta data to enable DKIM
processing to work a the far end after DKIM verifying the mailing
list input first. This gives you a trust chain.
Those are separate issues. We strip attachments because people send
messages that say "my kid's school play is tomorrow at 7 PM, tickets $5,
and here's a poster" and attach a 20MB powerpoint horror.
Wrapping messages to make them a one-message digest is 100% standards
compliant, and is one of the options in Mailman. The only problem is that
most MUAs render them unspeakably badly.
This is very well trodden ground. Look at the Mailman developers' list
where this has all been discussed to death.
Regards,
John Levine, johnl(_at_)taugh(_dot_)com, Taughannock Networks, Trumansburg NY
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