Thanks, Russ. And, yes, my comment about knowing when the experiment is over and what the results are... was something of a rant, and I agree that I can't think of anything useful to say. Sigh.
Anyway, thanks for addressing my comments. Barry On Mon, Dec 16, 2019 at 1:11 PM Russ Housley <hous...@vigilsec.com> wrote: > > Barry: > > You do not call for a response, but I want you to know that your comments are > being addressed. > > > ---------------------------------------------------------------------- > > COMMENT: > > ---------------------------------------------------------------------- > > > >> From the shepherd writeup: > > > > There was concern raised that no one has reported implementation > > of this draft. The document has experimental status and that helped > > gain working group consensus to move it forward. > > > > ...and... > > > > The document has been reviewed and is supported by a few > > working group members. Not everyone in the group agrees > > that it is needed, > > > > This seems to imply that making it Experimental was a tactic to get it > > through > > the working group, and that concerns me a bit, though not enough to get to > > DISCUSS. I would be happier if there were some discussion in the document > > about how we would determine that it is, indeed, needed and useful, and > > when we > > might know that we should move it to Standards Track or else abandon it. > > > > Unfortunately, I suspect the answer to that is that we won’t know until we > > have > > quantum computers to mount attacks with, and that won’t be until certain > > places > > freeze over. I realize that preparing for maybe someday having quantum > > computers and what they might someday do is an exercise that not everyone > > will > > want to spend time working on and implementing. > > I do not think we can add anything to the document. As was said on the email > thread on the TLS mail list, there is a plan to use it by the US government. > Others have not said one way or the other. > > > Some editorial comments, for which no reply is necessary: > > > > — Section 4 — > > > > Since the > > "tls_cert_with_extern_psk" extension is intended to be used only with > > initial handshakes, it MUST NOT be sent alongside the "early_data" > > extension. > > > > What happens if it is? Should this say that if they appear together the > > server > > aborts the handshake with an "illegal_parameter" alert? > > I added a paragraph: > > If the client includes both the "tls_cert_with_extern_psk" extension > and the "early_data" extension, then the server MUST terminate the > connection with an "illegal_parameter" alert. > > > The hash algorithm MUST > > be set when the PSK is established, with a default of SHA-256. > > > > If it MUST be set, how is there a default? > > This is stated in RFC 8446 in Section 4.2.11. > > > — Section 5 — > > > > If the server responds with a HelloRetryRequest > > message, then the client sends another ClientHello message as > > described in Section 4.1.2 of [RFC8446], including the same > > "tls_cert_with_extern_psk" extension as the original ClientHello > > message or abort the handshake. > > > > “, or aborts” (the comma closes the comma before “including”, and “aborts” > > is > > parallel to “sends”). > > Fixed. > > > — Section 5.1 — > > > > Most of those extension are > > not impacted in any way. This section discusses the impacts on the > > other extensions. > > > > Make it “those extensions”. And I would rephrase the second sentence as, > > “This > > section discusses the impacts on the extensions that are affected.” > > I suggest: > > Section 4 lists the extensions that are required to accompany the > "tls_cert_with_extern_psk" extension. Most of those extension are > used in the usual manner. This section discusses the impacts on the > extensions that are affected the presence of the > "tls_cert_with_extern_psk" extension. > > > The "psk_key_exchange_modes" extension restricts both the > > use of PSKs offered in this ClientHello and those which the server > > might supply via a subsequent NewSessionTicket. > > > > “Use of” needs to be factored out of the “both” clause: > > NEW > > ...restricts the use of both the PSKs offered in this ClientHello > > and those that the server might supply... > > END > > I accepted you better wording. > > > — Section 7 — > > > > the external PSKs and searching the resulting small set of > > possibilities, rather than brute force searching the whole key space. > > > > “and search”, and “brute-force” > > I accepted you better wording. > > > The reasoning is explained in [K2016] (see > > Section 4.2). > > > > I suggest “The reasoning is explained in Section 4.2 of [K2016].” > > Otherwise it > > sounds like you should see 4.2 of this doc (and I think the html links will > > be > > generated better this way). > > I accepted you better wording. > > > This specification does not require that external PSK is known only > > > > “that the external PSK” > > I added the missing article. > > Russ > > _______________________________________________ TLS mailing list TLS@ietf.org https://www.ietf.org/mailman/listinfo/tls
