Early Review of draft-ietf-tokbind-tls13-00
|Requested revision||No specific revision (document currently at 03)|
|Team||Security Area Directorate (secdir)|
|Requested by||Leif Johansson|
|I-D last updated||2018-03-29|
Secdir Early review of -00
by Stephen Kent
The WG would like early review from somebody in the TLS1.3 community.
|Reviewed revision||00 (document currently at 03)|
SECDIR *early* review of draft-ietf-tokbind-tls13-00 I have reviewed this document as part of the security directorate's ongoing effort to review all IETF documents being processed by the IESG.These comments were written with the intent of improving security requirements and considerations in IETF drafts.Comments not addressed in last call may be included in AD reviews during the IESG review.Document editors and WG chairs should treat these comments just like any other last call comments. This (very brief) document defines how to negotiate Token Binding for TLS v1.3. Existing IETF documents (IDs) define this protocol and how to negotiate it capability only for earlier versions of TLS. The first question that comes to mind is why there is a need for a new ID, instead of adding text to draft-ietf-tokbind-negotiation-10. I realize that draft-ietf-tokbind-negotiation-10 is in last call, but the text here is so small that it seems overkill to create a separate RFC. I’m guessing that the argument is that this document references TLS 1.3, which is not yet an RFC, and thus the author is trying to avoid creating a down reference problem with draft-ietf-tokbind-negotiation-10. Right? Section 2 notes that the format of the extension is the same as defined in draft-ietf-tokbind-negotiation-10, so nothing new there. The section cites two differences from the behavior in draft-ietf-tokbind-negotiation-10, which are described in just two sentences. Section 3 adds one paragraph to deal with 0-RTT, a TLS 1.3 feature not present in earlier versions.Section 4 is non-normative, but, presumably useful. The security concerns are asserted to be the same as for draft-ietf-tokbind-negotiation-10, plus a sentence discussing why the 0-RTT exclusion avoids other potential security concerns. So, if folks don’t want to delay publication of draft-ietf-tokbind-negotiation-10, I guess this is OK as a separate document, updating that RFC.