Re: [dane] Second WGLC draft-ietf-dane-smime

["John Levine" <[e-mail]>]

This draft is still a bad idea for all the reasons I described the
last time it came around.  Nothing has changed.

If you do publish it, I'd suggest much stronger language in the first
sentence of section 9 on security considerations.  The security model
for S/MIME certs has always been that the trust flows from the CA to
the user without involving the user's mail operator.  Now the domain
is the trust source for all of its users.  Sometimes that's
reasonable, sometimes not, and there's no way you can tell without
knowing information about the domain that's not in the DNS.

The fifth paragraph, on mail operator MITM attacks on user mail, is
also much too weak.  If the domain is a bank that is required by law
to archive its employee communications, MITM is reasonable.  If it's a
public mail operator that uses MITM to compile dossiers of user info
to sell to marketers, and to edit ads and web bugs into the messages
into mail before re-encrypting them, all without user permission, it's
not.  If the mail is from another user on the same system, it'll
re-sign the mail, too.  Of course, the mail operator will assure you
it's "required to be able to read everyone's encrypted email" by its
business plan.

R's,
John