Thanks for your feedback. Most of these are editorial comments and so I think they're my decision as editor about which ones to take absent some instruction from the chairs.
On Tue, Apr 4, 2023 at 10:43 PM Rob Sayre <say...@gmail.com> wrote: > Hi, > > I'm still not sure about the list/vector rename. Aside from that, here's > what I found: > > > It tightens some requirements and contains > > updated text in areas which were found to be unclear as well as other > > editorial improvements. > > "It contains clarifications and tightened requirements." [let's assume > some things were unclear and that editorial improvements are clarifications] > Not all editorial improvements are clarifications. > > > Forbid negotiating TLS 1.0 and 1.1 as they are now deprecated by > [RFC8996]. > > I know what's meant here, but deprecated does not mean forbidden. I think > you want to say "NOT RECOMMENDED" in RFC 2119 words, and give a brief > reason for that. [but keep reading] > This isn't normative text. However 8996 is entitled "Deprecating TLS 1.0 and TLS 1.1" so I think this is fine. > > The protocol does not provide any forward secrecy guarantees for this > data. > > The server's behavior determines what forward secrecy > > guarantees, if any, apply (see Section 8.1). This behavior is > > not communicated to the client as part of the protocol. > > Therefore, absent out-of-band knowledge of the server's behavior, > > the client should assume that this data is not forward secret. > > Here, you use the term "out-of-band", but the PSK text replaced > "out-of-band" with "external[ly]". I can't tell whether this usage is > intentional. > It is. The PSKs here are resumption PSKs. They're not external. The out of band in question is knowledge about the server behavior. > > > Because TLS 1.3 forbids renegotiation, if a server has negotiated TLS > > 1.3 and receives a ClientHello at any other time, it MUST terminate > > "TLS 1.3 forbids renegotiation. If a server has negotiated TLS 1.3 and > receives a ClientHello at any other time, it MUST terminate..." > > [No starting sentences with "Because"] > I believe this is editor discretion. > > > Note that [RFC8996] and Appendix E.5 forbid the negotation of TLS > > versions below 1.2; implementations which do not follow that guidance > > MUST behave as described above. > > I think this makes my "NOT RECOMMENDED" suggestion above correct. A > forbidden "MUST NOT" wouldn't need this text. > I don't understand this argument. The point of this text is that people are forbidden to do previous versions by 8996, but we know some people won't so this is backup guidance. I think this is fine. > > > Unless otherwise specified, trailing data is forbidden. > > That is, senders MUST NOT include data after the structure in the > > "extension_data" field. > > This doesn't seem like "MUST NOT", since it could be "otherwise > specified". I think there needs to be a harsher choice made here, or just > leave it out. > This is actually fairly standard language. > > When processing an extension, receivers MUST > > abort the handshake with a "decode_error" alert if there is data left > > over after parsing the structure. This does not apply if the > > receiver does not implement or is configured to ignore an extension. > > Again, doesn't seem like a "MUST". But the following text says "This does > not apply", without clarifying what "this" is. > I don't follow your argument here either. It's a MUST for any extension you understand. Obviously, if you don't understand it, you can't comply with this. I'll attempt to clarify. > > After checking ServerHello.random to determine if the server > > handshake message is a ServerHello or HelloRetryRequest, clients MUST > > check for this extension prior to processing the rest of the > > ServerHello. This will require clients to parse the ServerHello in ... > > Another "this". Here, I think the text means "This requirement...", but > usually a rewrite can fix these ambiguities. > I don't think this one is unclear. > > In the absence of some other specification to the > > contrary, servers which are authenticating with an external PSK MUST > > NOT send the CertificateRequest message either in the main handshake > > or request post-handshake authentication. [RFC8773] provides an > > extension to permit this, but has not received the level of analysis > > as this specification. > > Another one of these "In the absence of..." paragraphs. Maybe these are > intentional? They still sound really redundant to me. > They're intentional because we know there is actually such an RFC, but you have to actually use it. > > With a 128-bit key as in AES-128, rekeying 2^64 times has a high > > probability of key reuse within a given connection. Note that even... > > It's almost always possible to drop "Note that..." > It is possible, but I prefer to leave it as-is. > The rest of this paragraph is really heavy on em dashes, and needs to be > rewritten. Some of them seem to be parentheticals, but I would try to > rewrite it as short sentences. > I'll take a look. > > Note that it is common practice in some protocols to use the same > > Another "Note that" > See above. > > > Note that purely deterministic ECC signatures such as deterministic > ECDSA and EdDSA ... > > ... > > > If the resumption_master_secret has been > > compromised, a resumption handshake with EC(DHE) gives protection > > against passive attackers and a full handshake with EC(DHE) gives > > protection against active attackers. > > Here, you mean "resumption_secret". > Thanks. Good catch. > > > Note: This specification does not currently permit the server to send > > The old text was better. No "Note:". > > The "currently" part seems like the wrong thing to write in an immutable > document. Maybe "TLS 1.3 does not currently..."? > I don't think this is a problem. > > > In the absence of some other specification to the contrary, > implementations... > > I must be missing the conversation on this stuff. How could anyone write a > spec if every requirement was prefaced with "in the absence of some other > specification to the contrary..." > The purpose of this text is to signpost that we know that there might be or in fact is is such a specification, as opposed to other requirements which we don't have any reason to think that about. > > > Amplifying existing information leaks caused by side effects like > > caching. An attacker... > > Not a complete sentence here. I think it's just a typo. > Thanks. Will fix. -Ekr > > thanks, > Rob > > > > On Tue, Apr 4, 2023 at 7:32 PM Stephen Farrell <stephen.farr...@cs.tcd.ie> > wrote: > >> >> Hiya, >> >> On 05/04/2023 02:47, Sean Turner wrote: >> > A post IETF 116 bump to make sure folks get their reviews in. If you >> > look at the diffs from RFC 8446 you can see not that much has >> > changed. We will also take “I read it and it looks good” response. >> >> I looked at the diff between 8446bis-07 and 8446 and it seems >> fine to me. My only comment is that C.4 says one "SHOULD NOT >> reuse a key share" - I'd be happier if that was a "MUST NOT" >> but understand if we stick with SHOULD NOT. If there were a >> good reference showing that it's quite feasible to never >> deliberately re-use a key share, even at scale, that'd be a fine >> addition. (I don't have such a reference to offer, >> sorry;-) >> >> Cheers, >> S. >> _______________________________________________ >> TLS mailing list >> TLS@ietf.org >> https://www.ietf.org/mailman/listinfo/tls >> > _______________________________________________ > TLS mailing list > TLS@ietf.org > https://www.ietf.org/mailman/listinfo/tls >
_______________________________________________ TLS mailing list TLS@ietf.org https://www.ietf.org/mailman/listinfo/tls
