Re: [Ace] WGLC draft-ietf-ace-mqtt-tls-profile

[Marco Tiloca <[e-mail]>]

Hi,

Please, find below some comments. I think the document is overall well
written and in a good shape.

Best,
/Marco


[General]

* Refer the AIF adopted draft rather than the individual submission.

* Some references are included twice side by side, e.g. RFC 4949 and RFC
7800.


[Section 1]

* Add an inline reference to RFC 8446 for TLS 1.3. I think it's good
adding also references to CoAP and CBOR(-bis).


[Section 2.2.1]

* In the paragraph on "TLS:Known(RPK/PSK)-MQTT:none", the last two
sentences can clarify that they apply to TLS 1.2. As to the analogous
alternative provision of the token in PSK mode for TLS 1.3, that can
point to "identity" in the "identities" entry of "Pre-Shared Key"
ClientHello Extension.


[Section 2.2.4.1]

* Section 2.2.4 said that the two-byte integer length indicates the
amount of following bytes within Authentication Data. However this
section refers to the two-byte length as only the token length, i.e. it
does not seem to cover also the MAC/Signature (whose length might be
assumed from the used algorithm), even though that's still part of
Authentication Data. Could you please confirm or clarify?

* It's worth making it explicit that the PoP key is used to compute the
MAC or the client signature.

* s/and, the server/and the server

* Remove the final closed parenthesis.


[Section 2.2.4.2]

* Shouldn't the Authentication Data in the AUTH message from the server
start with a 2-byte server nonce length?

* Like for the AUTH message from the client, see the comment above for
Section 2.2.4.1 about what the 2-byte length covers (i.e., here too I
would have expected it to cover also the MAC/signature, not just the nonce).

* Like for the comment above for Section 2.2.4.1, it's worth making it
explicit that the PoP key is used to compute the MAC or the client
signature.


[Section 2.2.5]

* s/RS MUST verify/the RS MUST verify

* Please, add references for HS256 and Ed25519.


[Section 3]

* s/to all topic3/to all 'topic3'


[Section 6.1]

* s/as a UTF-8/is a UTF-8

================================


On 2020-09-01 22:54, Daniel Migault wrote:
> Hi, 
>
> This email starts a 2 weeks Working Group Last Call
> for draft-ietf-ace-mqtt-tls-profile. Please review the document
> available here [1] and provide your feed backs by September 15 2020.  
>
> Yours, 
> Jim and Daniel
>
> [1] https://datatracker.ietf.org/doc/draft-ietf-ace-mqtt-tls-profile/
>
>
> -- 
> Daniel Migault
> Ericsson
>
> _______________________________________________
> Ace mailing list
> [e-mail]
> https://www.ietf.org/mailman/listinfo/ace

-- 
Marco Tiloca
Ph.D., Senior Researcher

RISE Research Institutes of Sweden
Division ICT
Isafjordsgatan 22 / Kistagången 16
SE-164 40 Kista (Sweden)

Phone: [phone]
https://www.ri.se