jiebi/CodeConvo huggingface dataset:
Code change:
Implementations MUST either abandon an association or re-key prior to allowing the sequence number to wrap. <del> Implementations MUST NOT allow the epoch to wrap, but instead MUST establish a new association, terminating the old association. </del> 4.2.2. When receiving protected DTLS records, the recipient does not have a full epoch or sequence number value in the record and so there is <del> some opportunity for ambiguity.  Because the full epoch and sequence number are used to compute the per-record nonce, failure to reconstruct these values leads to failure to deprotect the record, and so implementations MAY use a mechanism of their choice to determine the full values.  This section provides an algorithm which is comparatively simple and which implementations are RECOMMENDED to follow. </del> <ins> some opportunity for ambiguity.  Because the full sequence number is used to compute the per-record nonce and the epoch determines the keys, failure to reconstruct these values leads to failure to deprotect the record, and so implementations MAY use a mechanism of their choice to determine the full values.  This section provides an algorithm which is comparatively simple and which implementations are RECOMMENDED to follow. </ins> If the epoch bits match those of the current epoch, then implementations SHOULD reconstruct the sequence number by computing

Related discussion:
text: NAME I don't think (D)TLS 1.3 puts any limits on ChaCha20 so my understanding is understanding is that the total number of packets can be protected in the current drafts is ChaCha20 2^64 (2^48 2^16) AES-GCM 2^40.5 (2^24.5 2^16) AES-GCM 2^39 (2^23 * 2^16)
NAME I am all for changing this now. I made a PR that change epoch from uint16 to uint32. As you say, it seems like a pretty easy change to do. Is uint32 the right size?
Unless you think we should do uint64. NAME NAME what would we have to do to make this change?
URL Magnus Westerlund thinks uint64 would be a safer bet.Michael Tüxen suggest to wrap the uint16 epoch instead. That might be an easier solution. I don't see a direct problem in DTLSPlaintext, ACK message, or recordsequencenumber with a uint16 epoch that is allowed to wrap like: 4, 5, ... 2^16-1, 4, 5, ... 2^16-1, 4, 5, ...
NAME NAME NAME since it's through the IESG we would need to at least raise that this change was made after they had approved it. I suspect that doing some kind of 2-week heads up to the WG/IESG that we want to make the change before landing it. But, if we do that or something more drastic that's really up to NAME
I want to point out that allowing wrapping per may not be the best solution if one considers to use the DTLS epoch as part of the input to the TLS exporter as suggested in . Then one want an input that doesn't wrap, and then to ensure that one doesn't practically run into any limits, then an uint64 would be better. An unit32 appears to be sufficient for a quite extreme use case with minimal messages size (which is one DTLS record with 4 byte user message) and high bandwidth (10 Gbps) sustained over a period of more than 5 years before the epoch would wrap.
Code change:
Implementations MUST either abandon an association or re-key prior to allowing the sequence number to wrap. <del> Implementations MUST NOT allow the epoch to wrap, but instead MUST establish a new association, terminating the old association. </del> 4.2.2. When receiving protected DTLS records, the recipient does not have a full epoch or sequence number value in the record and so there is <del> some opportunity for ambiguity.  Because the full epoch and sequence number are used to compute the per-record nonce, failure to reconstruct these values leads to failure to deprotect the record, and so implementations MAY use a mechanism of their choice to determine the full values.  This section provides an algorithm which is comparatively simple and which implementations are RECOMMENDED to follow. </del> <ins> some opportunity for ambiguity.  Because the full sequence number is used to compute the per-record nonce and the epoch determines the keys, failure to reconstruct these values leads to failure to deprotect the record, and so implementations MAY use a mechanism of their choice to determine the full values.  This section provides an algorithm which is comparatively simple and which implementations are RECOMMENDED to follow. </ins> If the epoch bits match those of the current epoch, then implementations SHOULD reconstruct the sequence number by computing

Related discussion:
text: With such long lifetimes we think mutual reauthentication, rekeying of the SCTP-AUTH key, and forcing attackers to dynamic key exfiltration [RFC7624] are required features. I still think should be done. 2^40.5 packets is quite limiting.
Seems OK.Thanks -- this LGTM. We'll need to do a brief consensus call given the type of change.
Code change:
6.5.1. SHOULD include a "Date" header field in Encapsulated Requests, unless <del> the does not use "Date" for anti-replay purposes. </del> <ins> the has prior knowledge that indicates that the does not use "Date" for anti-replay purposes. </ins> Though HTTP requests often do not include a "Date" header field, the value of this field might be used by a server to limit the amount of

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text: Comment by NAME In How does a client know this? Preconfiguration ? Are we talking ms? sec? minutes? Any advise to implementers ?
It can't be less than 2s, because the granularity of the field doesn't permit detecting anything finer than 1s. I've done what I can.
This still does not seem to address: Maybe just cut off the “unless” part if there is no signal for this? Paul
NAME also included URL which I think should address your concern:
Thanks. That commit does address the issue, mostly. I guess it moves it do an unspecified provisioning layer :P Paul
Code change:
9.8. <del> IANA has added the media type "application/edhoc" to the "Media Types" registry. </del> <ins> IANA has added the media types "application/edhoc+cbor-seq" and "application/cid-edhoc+cbor-seq" to the "Media Types" registry. 9.8.1. </ins> Type name: application <del> Subtype name: edhoc </del> <ins> Subtype name: edhoc+cbor-seq </ins> Required parameters: N/A

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text: Signed-off-by: David Navarro
NAME NAME and others: Any response to John's comment?
NAME I included John's suggestion in the PR.
Looks good to me. Other opinions?
As specified in section , the payload in some CoAP messages can be an EDHOC message prepended by either a C_x identifier or "true". The draft states: However, the payload is actually a CBOR Sequence as defined by . Thus, we could define and use a new media type "application/edhoc+cbor-seq". Note that the usage of the Content-Format option is optional.
Makes sense to me. NAME NAME others: Comments? Good that you bring up the optionality of Content-Format, we should stress that in this text. The discussion in Hackathon also reminded me about the common-option-compression which NAME presented in the May 12 interim 2021 - how to replace the Uri-Path: "/.well-known/edhoc" with a, say, integer valued CoAP option.
Makes a lot of sense to me, too.
I find this distinction good and the solution consequential, still open for comments.
Code change:
9.1. <ins> IANA has created a new registry titled "EDHOC Exporter Label" under the new heading "EDHOC".  The registration procedure is "Expert Review".  The columns of the registry are Label, Description, and Reference.  All columns are text strings.  The initial contents of the registry are: 9.2. </ins> IANA has created a new registry titled "EDHOC Cipher Suites" under the new heading "EDHOC".  The registration procedure is "Expert Review".  The columns of the registry are Value, Array, Description, and Reference, where Value is an integer and the other columns are text strings.  The initial contents of the registry are: <del> 9.2. </del> <ins> 9.3. </ins> IANA has created a new registry entitled "EDHOC Method Type" under the new heading "EDHOC".  The registration procedure is "Expert

Related discussion:
text: (Last two commits on wrong branch.)
The prototype of EDHOC-Exporter() has remained EDHOC-Exporter(label, length), while it should be EDHOC-Exporter(label, context, length) as per Alternative 3 discussed in issue URL Correct?
Thanks NAME your comment is addressed in the latest commit. I merge this now.
The text use both the terms "session" and "protocol instance", would be good to settle for one term.
Just chose one, I don't think this needs an issue
In the security considerations "session" makes most sense to me. There is also the term "connection". I will make a proposal.
The spec should likely forbid multiple calls to the EDHOC-Exporter interface with the same label, in order to prevent the same key being reused. Discussed with NAME and NAME
Good catch. Yes, we should have some text about that, but it should probably more be a requirement on the application using EDHOC that on EDHOC itself. Two different application should defintly not use the same label. The same application might rederive the same key several times as long as it keep track of its AEAD nonces and replay window. I thought that we had already IANA registry proposed for this, but that is not the case. We should probably have one. If we have a IANA registry the labels get more fixed and it might be that we need a context input parameter as well.
If we make a IANA registrer for labels, I think we need to let the application add additional information in some way. Two alternatives: We make an IANA register for label prefixes, and let the application append information to the label prefix. This was recently planned for EAP-TLS (and methods built on EAP-TLS) but was changes because the TLS export labels are not really ment to be labels. This would not change the current exporter interface. We expand the interface with a context parameter. This is similar to the TLS exporter. A problem with the TLS exporter is that some implementations decided to not even support context.
NAME how is the context parameter intended to be used? Could you give an example? Would this be some sort of "salt" when deriving the key?
Don't register labels, register label prefixes.
Code change:
9.1. <ins> IANA has created a new registry titled "EDHOC Exporter Label" under the new heading "EDHOC".  The registration procedure is "Expert Review".  The columns of the registry are Label, Description, and Reference.  All columns are text strings.  The initial contents of the registry are: 9.2. </ins> IANA has created a new registry titled "EDHOC Cipher Suites" under the new heading "EDHOC".  The registration procedure is "Expert Review".  The columns of the registry are Value, Array, Description, and Reference, where Value is an integer and the other columns are text strings.  The initial contents of the registry are: <del> 9.2. </del> <ins> 9.3. </ins> IANA has created a new registry entitled "EDHOC Method Type" under the new heading "EDHOC".  The registration procedure is "Expert

Related discussion:
text: The motivation for "context" or "label postfixes" is to increase the flexibility for the application. Restricting the application to IANA registered labels is very limiting. An application might want to use the EDHOC exporter to derive a number of keys and we should encourage that. The alternative is that the application needs to implement its own key derivation, which might be less secure and might be outside of the TEE. I called it "context" just because TLS calls the paramater in its exporter context.
"Be like TLS" is of course a good motivation. Technically, a label prefix is not different from a context, it just saves the need to separate prefix and suffix.
(And of course there is nothing wrong with multiple calls with the same label; the application has a "right to forget" :-)
The solutions should be equal when it comes to security. The choice should be made based on what is easiest for implementators and apllications using EDHOC. Alt 1. We make an IANA register for label prefixes: "OSCORE Master Secret" "OSCORE Master Salt" The Export function stays the same: EDHOC-Exporter(label, length) = EDHOC-KDF(PRK4x3m, TH4, label, length) An application is allowed to append things to the label prefix: "OSCORE Master Secret" "OSCORE Master Secret PickleRick" Alt 2. We make an IANA register for labels: label = "OSCORE Master Secret" label = "OSCORE Master Salt" The Export function needs to change: EDHOC-Exporter(label, ctx, length) = EDHOC-KDF(PRK4x3m, TH4, [label, ctx] , length) An application is not allowed to append things to the label and uses the ctx instead: label = "OSCORE Master Secret" ctx = "" label = "OSCORE Master Secret" ctx = "PickleRick"
No major opinion. Alt 2 breaks the test vector for the OSCORE security context. It would be good to get more input.
Any preference NAME NAME NAME ?
If desired the CTX is more convenient it can always be added in a wrapper on top of EDHOC-Exporter(). (I assume re-use of label+ctx in Alt 2 is equivalent to re-use of label in Alt 1?)
I prefer to have explicitly specified.
Code change:
9.1. <ins> IANA has created a new registry titled "EDHOC Exporter Label" under the new heading "EDHOC".  The registration procedure is "Expert Review".  The columns of the registry are Label, Description, and Reference.  All columns are text strings.  The initial contents of the registry are: 9.2. </ins> IANA has created a new registry titled "EDHOC Cipher Suites" under the new heading "EDHOC".  The registration procedure is "Expert Review".  The columns of the registry are Value, Array, Description, and Reference, where Value is an integer and the other columns are text strings.  The initial contents of the registry are: <del> 9.2. </del> <ins> 9.3. </ins> IANA has created a new registry entitled "EDHOC Method Type" under the new heading "EDHOC".  The registration procedure is "Expert

Related discussion:
text: We can pass to the concatenation of and . When is undefined/empty, test vectors are not affected. I guess this is what NAME is referring to?
label is a CBOR byte string. While alt 2 use an CBOR array. Definging alt2 as a wrapper seems more complication in my view.
Would be good if people stated alt 1. or alt 2. or made a concrete suggestion for alt 3.
Alt 3 (CBOR sequence) We make an IANA register for labels: label = "OSCORE Master Secret" label = "OSCORE Master Salt" The Export function needs to change: EDHOC-Exporter(label, ctx, length) = EDHOC-KDF(PRK4x3m, TH4, labelcontext, length) where is a CBOR sequence: If you want to keep the test vectors intact, then you could make optional in the CDDL, but not sure how to specify an optional parameter in the interface definition.
Thanks. That is a valid alt 3. but ctx should probably be a bstr
I don't think keeping the test vectors intact is an important goal at all. Let's decide on what is simplest for a user of the exporter interface.
Something like that, yes. Later post do differentiate the type of "label" and "ctx" and in light of that and changing test vectors Alt3 seems clean.
I am fine with alt 3. I can start making PR for that unless somebody has different ideas. I don't alt 1 is a good alternative anymore as is restricts context to being a unicode string. Which would require some base64 encoding or similar for a general context.
Please review alt. 3 as specified in . Unless there are any comments we would like to merge this.
This is included in -07 so I close the issue.
Comment by Martin Disch in URL "The draft does a good job of pointing to the right places in RFC 8152, but I still ended up trying to understand another ~100 page document just to implement the few constructs I actually needed." Should we provide more details about COSE constructs, e.g. in appendix A.2?
(pasting my response from the mailing list here for completeness) Thanks for following up on this. Yes, in my opinion expanding on the COSE constructs would be helpful.
Code change:
9.1. <ins> IANA has created a new registry titled "EDHOC Exporter Label" under the new heading "EDHOC".  The registration procedure is "Expert Review".  The columns of the registry are Label, Description, and Reference.  All columns are text strings.  The initial contents of the registry are: 9.2. </ins> IANA has created a new registry titled "EDHOC Cipher Suites" under the new heading "EDHOC".  The registration procedure is "Expert Review".  The columns of the registry are Value, Array, Description, and Reference, where Value is an integer and the other columns are text strings.  The initial contents of the registry are: <del> 9.2. </del> <ins> 9.3. </ins> IANA has created a new registry entitled "EDHOC Method Type" under the new heading "EDHOC".  The registration procedure is "Expert

Related discussion:
text: But I also sympathize with not wanting to duplicate what is already defined in another RFC (and possibly getting it wrong, as Carsten points out). Considering that there are quite a few implementers already and besides mine you have only received one other similar comment, maybe this isn't an issue for a meaningful majority. In any case, the draft has made great strides already in terms of accessibility and is in a good state now, so I don't see improvements in this area as an absolute necessity.
The two COSE constructs that are used in EHDOC, and are fairly simple. They don't use the recursive structure or embed . I think it is possible to add some additional clarifications on the structure of the COSE messages in the EHDOC draft without having to copy too much text from RFC 8152. As part of a thesis I built a proof-of-concept implementation of EDHOC in the Rust programming language available at URL The naming of the repository is due to the subject being both EDHOC and OSCORE on embedded devices, but the following refers only to the EDHOC implementation. It's based on draft-selander-ace-cose-ecdhe-14 and as such, sadly, outdated. Since it was just one part of the overall work, I only managed to implement the subset I needed, which is RPK and the signature-signature based scheme (corresponding to what draft-selander-lake-edhoc calls method 0). I also took some other shortcuts, such as not supporting auxiliary data. Fortunately, test vectors were about to be introduced just around the time I was working on it, so I've been able to successfully verify my implementation against them when John shared them with me for some preliminary testing. Since I didn't have any prior experience implementing this kind of software, I would definitely consider it more of an experiment, but it's out there and it works, in case it can be useful to anybody. I'm convinced that EDHOC will be valuable particularly in the context of OSCORE, possibly even beyond that. As for the draft itself, I would like to mention one aspect that I think could be improved from the perspective of an implementer. Part of the promise of EDHOC is that it's simple and lightweight due to reusing COSE.
Code change:
9.1. <ins> IANA has created a new registry titled "EDHOC Exporter Label" under the new heading "EDHOC".  The registration procedure is "Expert Review".  The columns of the registry are Label, Description, and Reference.  All columns are text strings.  The initial contents of the registry are: 9.2. </ins> IANA has created a new registry titled "EDHOC Cipher Suites" under the new heading "EDHOC".  The registration procedure is "Expert Review".  The columns of the registry are Value, Array, Description, and Reference, where Value is an integer and the other columns are text strings.  The initial contents of the registry are: <del> 9.2. </del> <ins> 9.3. </ins> IANA has created a new registry entitled "EDHOC Method Type" under the new heading "EDHOC".  The registration procedure is "Expert

Related discussion:
text: That is certainly the case, but breaks down somewhat when working on a system where no fully featured library for it is available. This was the case for me and I personally found it difficult to quickly figure out which aspects of COSE I needed to implement. The draft does a good job of pointing to the right places in RFC 8152, but I still ended up trying to understand another ~100 page document just to implement the few constructs I actually needed. I know the authors are aware of this and there has been some effort to inline more information directly in the specification, which I greatly appreciate. It would be very nice to have an entirely self-contained document to work with. But I have to again point out my lack of experience in that area, it's entirely possible that this draft is in fact much better than others in this regard and I just don't know it yet. With that I would like to support the adoption and am looking forward to seeing how it develops. Kind regards, Martin
Code change:
4.2. If an interaction response-interact-finish method is associated with <del> the current request, the AS MUST follow the appropriate method at upon completion of interaction in order to signal the client instance to continue, except for some limited error cases discussed below.  If a finish method is not available, the AS SHOULD instruct the RO to </del> <ins> the current request, the AS MUST follow the appropriate method upon completion of interaction in order to signal the client instance to continue, except for some limited error cases discussed below.  If a finish method is not available, the AS SHOULD instruct the RO to </ins> return to the client instance upon completion. The AS MUST create an interaction reference and associate that

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text: Just two minor typos I stumbled across.
Built To edit notification comments on pull requests, go to your .
Code change:
boot, or immutable hardware/ROM. It is also important that the appraisal policy was itself obtained <del> securely.  As such, if appraisal policies for a Relying Party or for a Verifier can be configured via a network protocol, the ability to create Evidence about the integrity of the entity providing the appraisal policy needs to be considered. </del> <ins> securely.  If an attacker can configure appraisal policies for a Relying Party or for a Verifier, then integrity of the process is compromised. </ins> The security of conveyed information may be applied at different layers, whether by a conveyance protocol, or an information encoding

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text: ` Does this mean to imply that bogus policy can’t be installed by sneakernet, e.g., on a usb thumb drive??
I don't think the 'via a network protocol' is necessary. The consideration is simply that policies have security considerations that are out of scope of the architecture.