[TLS] comments on draft-subcerts

[Sofía Celi <[e-mail]>]

Dear, list,

Sorry for sending this past the last call.

Few comments on the draft, which are:

- On Section 1:

"For clarity, we will refer to the certificate issued by the CA as a
"certificate", or "delegation certificate", and the one issued by the
operator as a "delegated credential" or "DC"."

I think this sentence can be their own paragraph, so it does not get
lost with the rest of the text. It will be good to clarify as well the
usage of 'credential', 'delegation', 'delegator' terms used through out
the document. It will be really nice to clarify the term 'credential' as
it sometimes seems to be used to refer to 'delegated credential', and
sometimes to the 'Credential' struct.

- On section 7.3

"Delegated credentials do not provide any additional form of early
revocation. Since it is short lived, the expiry of the delegated
credential would revoke the credential. Revocation of the long term
private key that signs the delegated credential also implicitly
revokes the delegated credential."

Not sure how the implicit revocation will work. It is my understanding
that the sole way to check that a DC is revoked is by verifying its
valid time, and this is the way that renders it 'invalid'.
Maybe, the DC is valid until it expires regardless if the long-term
private key is revoked, as I don't see a way to mark the DC invalid when
the long-term private key revokes. But perhaps, I'm understanding this
incorrectly.

In that case, how the DC signed by a revoked key will be treated? Should
it wait until they expire to render them completely explicitly invalid?


I have other minor editorial changes that I'll send as a PR.

Thanks!





-- 
Sofía Celi
@claucece
http://claucece.github.io/
Cryptographic research and implementation at many places, but mainly at
Cloudflare
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