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
