jiebi/CodeConvo huggingface dataset:
Code change:
Reference: [[this document]] <del> 9.7. </del> <ins> 9.8. </ins> The IANA Registries established in this document is defined as "Expert Review".  This section gives some general guidelines for what

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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:
Reference: [[this document]] <del> 9.7. </del> <ins> 9.8. </ins> The IANA Registries established in this document is defined as "Expert Review".  This section gives some general guidelines for what

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:
Reference: [[this document]] <del> 9.7. </del> <ins> 9.8. </ins> The IANA Registries established in this document is defined as "Expert Review".  This section gives some general guidelines for what

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:
Reference: [[this document]] <del> 9.7. </del> <ins> 9.8. </ins> The IANA Registries established in this document is defined as "Expert Review".  This section gives some general guidelines for what

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:
A PreSharedKey proposal is invalid if any of the following is true: The "psktype" in the PreSharedKeyID struct is not set to <del> "external". </del> <ins> "resumption" and the "usage" is "reinit" or "branch". </ins> The "psk_nonce" is not of length "KDF.Nh".

Related discussion:
text: Also covers the PSK part of
Interim 2022-05-26: Ready to go once merge conflicts are resolved.
The collection of structs could be less chatty. Suggest PreSharedKeys is only used once, can be inlined in GroupSecrets Use GroupContext for the internals of GroupInfo
Note: was fixed in In , we did: So only the following remain: Use GroupContext for the internals of GroupInfo
currently described at time of use. In the "Pre-Shared Keys" section, we should just specify that it must always be a fresh value of length The ReInit provisions require , but those for branching do not. Presumably these should be the same? Currently, the processing rules for PreSharedKey proposal says “MUST be external”. This seems overly restrictive; for example, it rules out the scenario in Figure 8. Suggest “MUST NOT be branch/reinit” instead.
Code change:
relatively short period of time, clients have an indication that the credential might have been created without the user's knowledge.  Due to the asynchronous nature of MLS, however, there may be transient <del> inconsistencies in a user's device set, so correlating users' clients </del> <ins> inconsistencies in a user's client set, so correlating users' clients </ins> across groups is more of a detection mechanism than a prevention mechanism.

Related discussion:
text: Particularly in multi-device scenarios (where a user has more than one device), we should recommend that clients correlate the set of devices of each user across groups. This would make it much harder for a malicious AS to issue fake device credentials for a particular user because clients would expect the credential to appear in all groups of which the user is a member. If a device credential does not appear in all groups after a while, clients have an indication that the credential might have been created without the user's knowledge. This should however only be a recommendation since it might not be a desirable property in all scenarios. In practical terms, users might also need some time to add their new device to all of the groups, therefore a grace period might be needed. Taking the latter into account, correlating users' devices across groups is more of a detection mechanism than a prevention mechanism.
"In many uses of MLS, there are multiple MLS clients which represent a single user (for example a human user with a mobile and desktop version of an application). Often the same set of clients is represented in exactly the same list groups. In applications where this is the case, clients can compare the set of devices of each user across groups. This would make it much harder for a malicious AS to issue fake device credentials for a particular user because clients would expect the credential to appear in all groups of which the user is a member. If a device credential does not appear in all groups after some relatively short period of time, clients have an indication that the credential might have been created without the user's knowledge. As this may take some time, correlating users' devices across groups is more of a detection mechanism than a prevention mechanism."
I lightly edited NAME prose and turned it into PR .
Made a quick pass. I think we should stick with "clients" rather than "devices".
Code change:
ServerConfiguration format. The semantics of this message are to establish a shared state between <del> the client and server for use with the "known_configuration" extension with the key specified in key and with the handshake </del> <ins> the client and server for use with the "early_data" extension with the key specified in "static_key_share" and with the handshake </ins> parameters negotiated by this handshake. When the ServerConfiguration message is sent, the server MUST also send a Certificate message and a CertificateVerify message, even if <del> the "known_configuration" extension was used for this handshake, thus </del> <ins> the "early_data" extension was used for this handshake, thus </ins> requiring a signature over the configuration before it can be used by the client.  Clients MUST NOT rely on the ServerConfiguration message until successfully receiving and processing the server's Certificate,

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text: Cleaned up references to knownconfiguration extension (merged into earlydata in draft-08)
Code change:
If the answer contains valid bundle groups, discard any ICE components for the "m=" sections that will be bundled onto the primary ICE components in each bundle, and begin muxing these "m=" <del> sections accordingly, as described in RFC8843. </del> <ins> sections accordingly, as described in I-D.ietf-mmusic-rfc8843-bis. </ins> If the description is of type "answer" and there are still remaining candidates in the ICE candidate pool, discard them.

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text: and
To resolve WGLC comments: URL it was agreed to incorporate a reference to this text in 8843bis: URL That text ended up in s7.6.
When draft-8843bis is given an RFC number, this draft should reference the new RFC. Hi, Eventhough I would not like to make more changes than necessary, I am fine with "3PCC Considerations". However, your suggested text is very difficult to understand in some places, so let me give it a try. (The first paragraph is generic, the second SIP specific, and the third BUNDLE specific.) 3PCC Considerations In some 3PCC scenarios a new session will be established between an endpoint that is currently part of an ongoing session and an endpoint that is currently not part of an ongoing session. The endpoint that is part of a session will generate a subsequent offer that will be forwarded to the other endpoint by a 3PCC controller. The endpoint that is not part of a session will process the offer as an initial offer. The Session Initiation Protocol (SIP) [RFC3261] allows a User Agent Client (UAC) to send a re-INVITE request without an SDP body (sometimes referred to as an empty re-INVITE). In such cases, the User Agent Server (UAS) will include an SDP offer in the associated 200 OK response. If the UAS is a part of an ongoing session, it will include a subsequent offer in the 200 OK response. The offer will be received by a 3PCC controller (UAC) and then forwarded to another User Agent (UA). If the UA is not part of an ongoing session, it will process the offer as an initial offer. When the BUNDLE mechanism is used, an initial BUNDLE offer is constructed using different rules than subsequent BUNDLE offers, and it cannot be assumed that a UA is able to correctly process a subsequent offer as an initial offer. Therefore, the 3PCC controller SHOULD rewrite the subsequent offer into a valid initial offer, following the procedures in (Section 7.2), before it forwards the offer to a UA.
Code change:
If the answer contains valid bundle groups, discard any ICE components for the "m=" sections that will be bundled onto the primary ICE components in each bundle, and begin muxing these "m=" <del> sections accordingly, as described in RFC8843. </del> <ins> sections accordingly, as described in I-D.ietf-mmusic-rfc8843-bis. </ins> If the description is of type "answer" and there are still remaining candidates in the ICE candidate pool, discard them.

Related discussion:
text: In the rewritten offer the 3PCC controller will set the port value to zero (and include an SDP 'bundle-only' attribute) for each "m=" section within the BUNDLE group, excluding the offerer-tagged "m=" section. __ From: Roman Shpount Sent: Tuesday, November 2, 2021 6:33 PM To: Christer Holmberg Cc: Justin Uberti ; Justin Uberti ; RTCWeb IETF Subject: Re: [rtcweb] Working Group Last Call for draft-uberti-rtcweb-rfc8829bis-URL How about we replace the SIP Considerations with: 3PCC Considerations In some 3PCC scenarios, an offer generated during an ongoing session, i.e., a subsequent offer, will be used by a 3PCC controller to establish a new session and forwarded as an initial offer to another endpoint that is currently not part of a session. For example, the Session Initiation Protocol (SIP) [RFC3261] allows a User Agent Client (UAC) to send a re-INVITE request without an SDP body (sometimes referred to as an empty re-INVITE). In such cases, the User Agent Server (UAS) will include an SDP offer in the associated 200 OK response. If UAS is a part of an ongoing session, it will include a subsequent offer in the 200 OK response. The offer will be received by a 3PCC controller (UAC) and then forwarded to another User Agent (UA) as an initial offer. When the BUNDLE mechanism is used, an initial BUNDLE offer is constructed using different rules than subsequent BUNDLE offers. It cannot be assumed that a subsequent offer is a valid initial offer and that the endpoint that expects an initial offer will properly process such a subsequent offer. Therefore, the 3PCC controller SHOULD rewrite the subsequent offer into a valid initial offer before it is used to establish a new session. To make the subsequent offer a valid initial offer, 3PCC will need to modify all the non-tagged m= lines to include the bundle-only attribute and set the m= line port to zero.
Code change:
If the answer contains valid bundle groups, discard any ICE components for the "m=" sections that will be bundled onto the primary ICE components in each bundle, and begin muxing these "m=" <del> sections accordingly, as described in RFC8843. </del> <ins> sections accordingly, as described in I-D.ietf-mmusic-rfc8843-bis. </ins> If the description is of type "answer" and there are still remaining candidates in the ICE candidate pool, discard them.

Related discussion:
text: _ Roman Shpount Christer Holmberg > wrote: Hi, What about something like this: OLD: “The Session Initiation Protocol (SIP) [RFC3261] allows a User Agent Client (UAC) to send a re-INVITE request without an SDP body (sometimes referred to as an empty re-INVITE). In such cases, the User Agent Server (UAS) will include an SDP Offer in the associated 200 OK response. This is typically used for 3rd Party Call Control (3PCC) scenarios. >From a BUNDLE perspective, such SDP Offer SHOULD be generated using the procedures defined in Section 7.2.” NEW: “The Session Initiation Protocol (SIP) [RFC3261] allows a User Agent Client (UAC) to send a re-INVITE request without an SDP body (sometimes referred to as an empty re-INVITE). In such cases, the User Agent Server (UAS) will include an SDP offer in the associated 200 OK response. This is typically used for 3rd Party Call Control (3PCC) scenarios. In some 3PCC scenarios the UAS will be part of an ongoing session, and will therefore include a subsequent offer in the 200 OK responses. The offer will be received by a 3PCC controller (UAC) and then forwarded as an initial offer to another User Agent (UA) that is currently not part of a session. When the BUNDLE mechanism is used, as an initial BUNDLE offer look different than a subsequent BUNDLE offer, it cannot be assumed that a UA that expects an initial offer will be able to properly process a subsequent offer.
Code change:
If the answer contains valid bundle groups, discard any ICE components for the "m=" sections that will be bundled onto the primary ICE components in each bundle, and begin muxing these "m=" <del> sections accordingly, as described in RFC8843. </del> <ins> sections accordingly, as described in I-D.ietf-mmusic-rfc8843-bis. </ins> If the description is of type "answer" and there are still remaining candidates in the ICE candidate pool, discard them.

Related discussion:
text: Therefore, the 3PCC controller needs to act as a Back-To-Back User Agent (B2BUA), and when it receives the subsequent offer it needs to rewrite it into an initial offer before it is forwarded to such UA.” Regards, Christer From: Roman Shpount > Sent: tiistai 2. marraskuuta 2021 10.41 To: Justin Uberti > Cc: Christer Holmberg >; Justin Uberti >; RTCWeb IETF > Subject: Re: [rtcweb] Working Group Last Call for draft-uberti-rtcweb-rfc8829bis-URL The PROBLEM is that we have two endpoints, where one sends a subsequent offer, and the other one expects an initial offer. What do you normally do when you have that kind of problem? You use an SBC/B2BUA. In this case that SBC/B2BUA would be the 3PCC controller. So, my suggestion would be to remove the SHOULD text from 8843bis, and simply add a note somewhere (in 8843bis and/or 8829bis) which describes the issue and says that the 3GPP controller needs to modify the offer accordingly. Roman, thoughts on this? If the 3PCC is going to rewrite the offer SDP anyway then maybe adding a=bundle-only isn't the end of the world. I am not opposed to this idea. 3PCC typically knows that the subsequent offer is going to be used as initial, and should be able to rewrite the offer to make it valid. We can change SIP Considerations section in 8843bis (URL), remove the SHOULD, and specify that 3PCC controller should fix the offer. We can then reference this note from 8829bis or restate the same guidance. Roman Shpount
Not seeing any objections for a month then once -02 is submitted we will progress this towards our AD. spt
Code change:
of the first ClientHelloInner via the derived ech_hrr_key by modifying HPKE setup as follows: <del> Clients then encrypt the second ClientHelloInner using this new HPKE context.  In doing so, the encrypted value is also authenticated by ech_hrr_key.  The rationale for this is described in flow-hrr-hijack. </del> <ins> The "info" parameter to SetupPSKS is the concatenation of "tls ech", a zero byte, and the serialized ECHConfig.  Clients then encrypt the second ClientHelloInner using this new HPKE context.  In doing so, the encrypted value is also authenticated by ech_hrr_key.  The rationale for this is described in flow-hrr-hijack. </ins> Client-facing servers perform the corresponding process when decrypting second ClientHelloInner messages.  In particular, upon

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text: The spec describes an optional trial decryption mode, but most of the text contradicts it. This PR fixes the text up and tries to unify their processing models. In doing so, it flips the error handling from decrypterror to fallback to be consistent. This, combined with the ClientHelloOuterAAD change, plugs an active sticking out attack for free. It also makes easier because GREASE configid collisions with real configids are now harmless. Along the way, NAME and NAME observed that we're not authenticating the ECHConfig at all. (It used to be authenticated by way of the configid, which was a digest.) Instead, just pass the ECHConfig into the info field of the HPKE context. They also noticed the server rule about PSKs on ClientHelloOuter didn't work with GREASE. Instead, we can simply remove it.
This matches the acceptance signal length, and we've already accepted that probability of collision.