jiebi/CodeConvo huggingface dataset:
Code change:
6.4. DNS resolvers that support DDR by responding to queries for <del> _dns.resolver.arpa SHOULD treat resolver.arpa as a locally served zone per RFC6303.  In practice, this means that resolvers SHOULD respond to queries of any type other than SVCB for _dns.resolver.arpa with NODATA and queries of any type for any domain name under </del> <ins> _dns.resolver.arpa MUST treat resolver.arpa as a locally served zone per RFC6303.  In practice, this means that resolvers SHOULD respond to queries of any type other than SVCB for _dns.resolver.arpa with NODATA and queries of any type for any domain name under </ins> resolver.arpa with NODATA. 6.5.

Related discussion:
text: Spoofing an SVCB to a bogus IP with an SVCB TTL of a few hours would be a very cheap 1 packet attack to keep the DNS client down for hours. This seems dangerous to implement. unencrypted DNS MUST NOT provide differentiated behavior based on the HTTP path alone, since an attacker could modify the "dohpath" parameter. For example, if a DoH resolver provides provides a filtering service for one URI path, and a non-filtered service for another URI path, [...] It seems likely that this advise will get ignored a lot, eg by people who have limited public IPs to use to spin up a DoH server, or who have to pay-per-IP. This advise seems more appropriate for local private IP DoH servers. So I would change this MUST NOT to SHOULD NOT for that reason. Unencrypted Resolver, clients applying Verified Discovery (Section 4.2) MUST validate that the IP address of the Unencrypted Resolver is covered by the SubjectAlternativeName of the Designated Resolver's TLS certificate. How would one obtain such a certificate via ACME? Since on the IP of the unencrypted resolver, there would be no HTTP server running? Additionally, if the client notices a failed verification of the Designated Resolver's TLS certificate, wouldn't it fallback to the Unencrypted Resolver? But now it may not? So this becomes a denial of service then ? to cases where the Unencrypted Resolver and Designated Resolver have the same IP address. Based on earlier text, this should read "the same non-public IP address". you use "unilateral probing" (draft-ietf-dprive-unilateral-probing) to just connect to the DoT or DoQ ports of the Unencrypted Resolver and see if you get anything back. It might be unauthenticated TLS but better than port 53? Special-Use Domain Names (SUDN) registry established by [RFC6761]. Why not pick URL As .local is already handled to not be forwarded by DNS forwarders. It would also not require an addition to SUDN. Even if someone was already using URL, it would not interfere with that usage because that usage would not be using SVCB records.
Code change:
6.4. DNS resolvers that support DDR by responding to queries for <del> _dns.resolver.arpa SHOULD treat resolver.arpa as a locally served zone per RFC6303.  In practice, this means that resolvers SHOULD respond to queries of any type other than SVCB for _dns.resolver.arpa with NODATA and queries of any type for any domain name under </del> <ins> _dns.resolver.arpa MUST treat resolver.arpa as a locally served zone per RFC6303.  In practice, this means that resolvers SHOULD respond to queries of any type other than SVCB for _dns.resolver.arpa with NODATA and queries of any type for any domain name under </ins> resolver.arpa with NODATA. 6.5.

Related discussion:
text: To avoid name lookup deadlock, Designated Resolvers SHOULD follow the guidance in Section 10 of [RFC8484] regarding the avoidance of DNS- based references that block the completion of the TLS handshake. I find that reference to list more the issues than solutions that can be followed. The solution to use another DoH server is not really appropriate in most cases The client's other interface likely resides on other networks where its private DoH server cannot resolve the name of another network's private DoH server. It is also not easy to get an IP based certificate (eg SAN=ip) that is accepted by general webpki root stores. And things like OCSP stapling doesn't help if the target is malicious - they just would omit the stapling that proves against its malicious use. The only real advise usable from RFC8484 is "use the local unencrypted resolver to resolve the encrypted resolver". Might as well say that and remove the 8484 reference. as the protocol is mentioned throughout the document as interacting with this protocol. when accessing web content on a dual-stack network: A, AAAA, and HTTPS queries. Discovering a Designated Resolver as part of one of these queries, without having to add yet another query, minimizes the total number of queries clients send. I don't understand this paragraph. Once clients can send SVCB queries for web content, they already have had to do all the DDR/DNR related queries, so I don't understand the argument of "saving queries" ? Also, it is adding queries for a specific target, eg URL, and this cannot be "saved" either? What am I misunderstanding here? provides provides -> provides
We should reference Security Considerations, because if you don't have any validation, an attacker can point you to any server they want (someone other than the server you were configured with by DHCP, etc).
We can probably just remove this, not using it in implementations right now.
It's already done by the major public resolvers, and there is an RFC to support this (RFC 8738). The IP address validation is clearly important and a matter of WG consensus. Hopefully, this will push adoption of RFC 8738 by more ACME services.
We can reference the DNR section. The MUST NOT should only apply to DDR, but doesn't invalidate other ways of using the resolver.
Code change:
6.4. DNS resolvers that support DDR by responding to queries for <del> _dns.resolver.arpa SHOULD treat resolver.arpa as a locally served zone per RFC6303.  In practice, this means that resolvers SHOULD respond to queries of any type other than SVCB for _dns.resolver.arpa with NODATA and queries of any type for any domain name under </del> <ins> _dns.resolver.arpa MUST treat resolver.arpa as a locally served zone per RFC6303.  In practice, this means that resolvers SHOULD respond to queries of any type other than SVCB for _dns.resolver.arpa with NODATA and queries of any type for any domain name under </ins> resolver.arpa with NODATA. 6.5.

Related discussion:
text: If they are different, it can be a random attacker (see security considerations). The client may also have other better options to fall back to.
Agree, this should be simplified to say "even if you connect over a different IP address for any reason, still validate the original IP address"
There are definitely cases where the client can have directly selected their own resolver name, etc. We don't have to use the network resolver.
Correct, and that's why we need this document, and it was added to the IANA section.
Sure, we can make this a MUST.
It makes the attacker's job harder by requiring them to be persistent. Normal retransmission logic is fine too.
This is a direct outcome of the svcb-dns document. Spoofing SVCB shouldn't be enough to cause a DoS here, because we should continue to use the previously used encrypted DNS server while on this network (even if you get a bad SVCB packet).
For the security reasons, I think this needs to stay as a MUST NOT. However, if you differentiate based on hostname + path, you can still differentiate, it just isn't a differentiation that can be discovered by IP address queries.
Yes, you'd fall back to unencrypted resolution if you can't have a secure trusted connection for encrypted resolution.
Yes, but that part is SHOULD. Will fix.
I think that's just opportunistic DoT / DoQ. That's already specified.
.local is the SUDN for multicast DNS, but it is also squatted on by some internal networks. Following the patterns for URL, etc, .arpa is a much more appropriate name. This is what the group had consensus on years ago and has been deployed widely already.
I think we can say "as explained in RFC 8484, don't loop on the resolver name."
Sure, that's fine.
Yeah, this paragraph is old and can be removed.
Looks good! Just silly editorial nits
Code change:
In pseudocode, this procedure is as follows: <ins> The retains the HPKE context, "rctxt", so that it can encapsulate a response. </ins> 4.4. <del> Given an HPKE context, "context"; a request message, "request"; and a response, "response", generate an , "enc_response", as follows: </del> <ins> generate an , "enc_response", from a binary encoded HTTP response BINARY, "response".  The uses the HPKE receiver context, "rctxt", as the HPKE context, "context", as follows: </ins> Export a secret, "secret", from "context", using the string "message/bhttp response" as the "exporter_context" parameter to

Related discussion:
text: Why is it that media type registration is a journey of discovery each and every time? It's like the coastline paradox: the closer you get, the more detail resolves. Also, each requirement makes sense in isolation, but if you need an entire RFC to explain it, maybe something has gone wrong.
no strong feelings on this one.
Code change:
triggering Initial packet.  This is in cleartext to be readable for the server, but authenticated later in the token. <ins> RSCIL: The retry source connection ID length. </ins> Original Destination Connection ID: This also in cleartext and authenticated later. <ins> Retry Source Connection ID: This also in cleartext and authenticated later. </ins> Opaque Data: This data MUST contain encrypted information that allows the retry service to validate the client's IP address, in accordance <del> with the QUIC specification.  It MUST also encode a secure hash of the original destination connection ID field to verify that this field has not been edited. </del> <ins> with the QUIC specification.  It MUST also provide a cryptographically secure means to validate the integrity of the entire token. </ins> Upon receipt of an Initial packet with a token that begins with '0', the retry service MUST validate the token in accordance with the QUIC <del> specification.  It must also verify that the secure hash of the Connect ID is correct.  If incorrect, the token is invalid. </del> <ins> specification. </ins> In active mode, the service MUST issue Retry packets for all Client initial packets that contain no token, or a token that has the first bit set to '1'.  It MUST NOT forward the packet to the server.  The service MUST validate all tokens with the first bit set to '0'.  If successful, the service MUST forward the packet with the token <del> intact.  If unsuccessful, it MUST drop the packet. </del> <ins> intact.  If unsuccessful, it MUST drop the packet.  The Retry Service MAY send an Initial Packet containing a CONNECTION_CLOSE frame with the INVALID_TOKEN error code when dropping the packet. </ins> Note that this scheme has a performance drawback.  When the retry service is in active mode, clients with a token from a NEW_TOKEN

Related discussion:
text: After thinking it through, various XOR schemes were extremely vulnerable to manipulation, so I went with a brute force approach.
The server now needs to include this field. For the no-shared state service, we just need language that the Retry service needs to encode enough information validate the packet DCID as well and drop if it fails validation. If it does, the server MUST use the packet DCID in the retrysourceconnection_id TP. For the shared state service, the retry source connection ID is going to have to be in the token. We might be able to compress this by xoring some fields; I'll think about it.
Code change:
2.4.4. <del> The "length" function extension provides a way to compute the length of a value and make that available for further processing in the filter expression: </del> <ins> The "length()" function extension provides a way to compute the length of a value and make that available for further processing in the filter expression: </ins> Its only argument is an instance of "ValueType" (possibly taken from a singular query, as in the example above).  The result also is an

Related discussion:
text: Use parentheses as an indication that something is a function. Also, don't confuse the reader by alluding to potential future alternatives to value(). Reviewers: is this an improvement? It's a draft PR for now until we decide the change is worthwhile.
I think we'll need to explain the () notation, which should be familiar to C programmers but not necessarily to people who grew up on other languages. I also think we have a few more examples that point to hypothetical functions, such as , , .
I don't think there's a great point at which to explain that notation and, based on your observation, I'm going off the idea.
NAME Let's see how pans out before taking the current PR any further. Once I remove the function parentheses, the two PRs are changing the same text.
would be the place.
NAME As you suggested, I introduced this in 1.1, but near the start since it's notation rather than terminology. I did a regexp search to find and fix the remaining examples (your list was complete). In doing so, I found the strange markup and removed the backticks since there was no good reason for them.
We could do the fun() explanation and completeness search in a separate PR.
Code change:
An endpoint MAY send ACK-FREQUENCY frames multiple times during a connection and with different values. <del> 4. An endpoint could receive an ACK-FREQUENCY frame with either or both Time Tolerance and Packet Tolerance values specified.  In addition, the endpoint will have committed a max_ack_delay value to the peer, </del> <ins> An endpoint will have committed a max_ack_delay value to the peer, </ins> which specifies the maximum amount of time by which the endpoint will <del> delay sending acknowledgments; see Section XX of QUIC-TRANSPORT. </del> <ins> delay sending acknowledgments.  When the endpoint receives an ACK- FREQUENCY frame, it MUST update this maximum time to the value proposed by the peer in the Update Max Ack Delay field. </ins> <del> The endpoint MUST send an acknowledgement when any of the three thresholds are met.  Doing so results in the fewest acknowledgements possible within the sender's tolerance and honors the receiver's commitment. loss and batch section describes exceptions to this strategy. </del> <ins> 5. On receiving an ACK-FREQUENCY frame, an endpoint will have an updated maximum delay for sending an acknowledgement, and a packet threshold as well.  The endpoint MUST send an acknowledgement when either of the two thresholds are met. loss and batch section describes exceptions to this strategy. </ins> An endpoint is expected to bundle acknowledgements when possible. Every time an acknowledgement is sent, bundled or otherwise, all counters and timers related to delaying of acknowledgments are reset. <del> 4.1. </del> <ins> 5.1. </ins> To expedite loss detection, endpoints SHOULD send an acknowledgement immediately on receiving an ack-eliciting packet that is out of

Related discussion:
text: This PR changes a few things: Introduces a TP for negotiating extension use Changes to Makes the fields required Specifies invalid values
I'm merging this, let's address issues in later PRs.
I think it'll be easier to make both parameters required. Not doing so saves 1 to 2 bytes, which is really not much in a frame I expect will be sent a few times a connection. Also, I think 0 should be an invalid value for both params, and 1 should be invalid for the number of packets, though I can see someone arguing that point.
addresses these issues, with the exception that 1 is allowed for packet tolerance. I think that's actually useful for some startup schemes, so we shouldn't disallow it.
Code change:
"rrc" extension to the "TLS ExtensionType Values" registry as described in tbl-ext. <del> 8. </del> <ins> 9. </ins> Issues against this document are tracked at https://github.com/tlswg/ dtls-rrc/issues <del> 9. </del> <ins> 10. </ins> We would like to thank Achim Kraus, Hanno Becker, Hanno Boeck, Manuel Pegourie-Gonnard, Mohit Sahni and Rich Salz for their input to this

Related discussion:
text: and
For example, allow multiple outstanding path_challenge messages to cater for potential packet loss.
We want to limit the application data sent to a reasonable threshold while we run the RRC.
RFC 9000, section 8 "address validation" (second paragraph, last line): 3 times the amount of data received.
Here is the text: Address Validation Address validation ensures that an endpoint cannot be used for a traffic amplification attack. In such an attack, a packet is sent to a server with spoofed source address information that identifies a victim. If a server generates more or larger packets in response to that packet, the attacker can use the server to send more data toward the victim than it would be able to send on its own. The primary defense against amplification attacks is verifying that a peer is able to receive packets at the transport address that it claims. Therefore, after receiving packets from an address that is not yet validated, an endpoint MUST limit the amount of data it sends to the unvalidated address to three times the amount of data received from that address. This limit on the size of responses is known as the anti-amplification limit.
Code change:
8.2.2. <del> message </del> <ins> application </ins> <del> access-token-response </del> <ins> private-token-response </ins> N/A

Related discussion:
text: I also moved from the message namespace to the application namespace. The difference is helpfully summarized .
I see in the current draft that they register and . Since "token" is a very broad term, I'm wondering if something slightly more specific to Privacy Pass such as and might be reasonable?
If we make it more specific, it should be "private" instead of "privacy", to be "private-token" and align with the auth scheme. There's a fair amount of deployment on these types today, so this would be a relatively large change, or servers would need to tolerate both versions.
I'm in favor of making this change and having issuers support both for a little while.
Cool, that would work. NAME want to make the proposed update?
Will do!
NAME PR's up!
Looks good!
Code change:
For a KeyPackageRef, the "value" input is the encoded KeyPackage, and the ciphersuite specified in the KeyPackage determines the KDF used. <del> For a LeafNodeRef, the "value" input is the LeafNode object for the leaf node in question.  For a ProposalRef, the "value" input is the MLSMessageContentAuth carrying the proposal.  In the latter two cases, the KDF is determined by the group's ciphersuite. </del> <ins> For a ProposalRef, the "value" input is the MLSMessageContentAuth carrying the proposal.  In the latter two cases, the KDF is determined by the group's ciphersuite. </ins> 6.3.

Related discussion:
text: This seems to be a layer of indirection that doesn't add any value to implementation.
The Credentials section claims there is an epoch id field in key packages. I don't think that actually exists. My apologies if this is a duplicate issue.
Addressed in but may need to be pulled out depending on the fate of that PR
contains all of the Proposals that were previously sent within the same epoch. This seems unnecessary, since all members should have them anyway. The list of in the actual message should be enough for members to parse and validate a message. We should discuss if we can de-duplicate this, since the list of Proposals might be quite long.
The current definition of is as follows; Maybe this issue is obsolete?
Seems it is now obsolete indeed.
I don't have a strong opinion on this question, but this change seems sensible to me. The use of LeafNodeRef requires either (a) a linear scan through the tree, which is time-expensive in large trees, or (b) keeping an index that maps LeafNodeRef values to indices, which is storage-intensive in large trees. IIRC, the change to LeafNodeRef was made in the context of NAME work to make the tree description less tied to the array representation. In general, that is the right thing to do, and it's good that we did it. But we still have leaf indices anyway, for . Since we still have the concept, we might as well use it where it makes sense. And it certainly seems to me like and make sense, since they are internal to the protocol. In case folks are worried about the application-facing API -- MLS stacks can certainly be more intelligent, e.g., exposing or or . But they can do that regardless of this PR.
Code change:
that the epoch secret is confidential to the members in the current epoch. <del> For each Commit that adds one or more members to the group, there is a single corresponding Welcome message.  The Welcome message provides all the new members with the information they need to initialize </del> <ins> For each Commit that adds one or more members to the group, there are one or more corresponding Welcome messages.  Each Welcome message provides new members with the information they need to initialize </ins> their views of the key schedule and ratchet tree, so that these views align with the views held by other members of the group in this epoch.

Related discussion:
text: For example, if you use OpenSSL to validate the chain it does not take a chain as input. It takes a collection of certificates, a set of trusted root certs, and the leaf you want to validate. I believe not making this change has a higher complexity.
I'm sorry I missed this previously, but this requirement was a source of trouble in TLS and was removed in RFC 8446, which allows extra certificates in the middle. Was there a conscious decision to be more strict here.
I don't recall this ever being discussed. I think it was just added and nobody ever objected.
NAME can you elaborate a little bit? The way I read it the requirement is just that there is a valid signature chain, i.e. that one certificate signs the next and so on.
NAME - I deliberately reverted to the original TLS level of strictness here, in hopes that in starting over with a new ecosystem we could reset things to a cleaner state. Do you think there are legitimate reasons for violating the strict rule, or is it just a common misconfiguration in TLS servers? I would not really be inclined to accommodate the latter. NAME - I believe what NAME is envisioning are cases where there are multiple valid chains, say via old and new versions of an intermediate certificate. So you might do something like provide a "chain" of the form (leaf, oldintermediate, newintermediate), with the idea that the client could verify using whichever one makes it happy.
NAME take a look at the comment I left on the PR. I can see your point about starting over as being valid, but one thing that also caught my eye in the TLS RFC was language around allowing a root CA to be left out of the chain since those could potentially already exist in a local trust store.
I see. Thanks NAME for the clarification. Maybe we can phrase it in such a way that whatever the credential includes (added intermediary certificates or left-out root certificates) in the end the local client MUST be able to create a continuous certificate chain from the leaf to the root. Do we need to define how the client does that? Since we're already pushing everything else related to authentication into the AS, I'm inclined to say no.