Poking around the Linux kernel source, my reading of net/ipv6/icmp.c's icmpv6_rcv() is that it checks the type byte before dispatching to icmpv6_echo_reply(), and inside icmpv6_echo_reply() I'm not seeing any checking of the code byte, so I'd assume (without testing) that it just constructs a normal echo reply. I also suspect that it just copies the incoming code value into the reply.
The only differentiation I see being made is between echo request (4443) and extended echo request (8335). Should be easy enough to test (after I get a few other things done). On Tue, Jun 6, 2023 at 9:30 PM Tal Mizrahi <tal.mizrahi....@gmail.com> wrote: > > Bob, Eric, > > Thanks for the feedback. > Defining a new code for ICMPv6 Echo rather than defining a new type > may be the right way to go. > Our main concern with this is that RFC 4443 defines what to do with an > unknown type, but does not define what to do with an unknown code. It > is not clear what existing implementations do when receiving an Echo > Request with an unknown code. That is why the current draft calls for > a new type. However, we are open to more feedback about this, and it > may end up being just a new code. > > Cheers, > Tal. > > On Tue, Jun 6, 2023 at 8:33 PM Eric Vyncke (evyncke) <evyn...@cisco.com> > wrote: > > > > Without any hat, I agree with Bob. > > > > This I-D should eventually go to 6MAN WG though (with my AD hat) > > > > -éric > > > > On 06/06/2023, 08:34, "Int-area on behalf of Bob Hinden" > > <int-area-boun...@ietf.org <mailto:int-area-boun...@ietf.org> on behalf of > > bob.hin...@gmail.com <mailto:bob.hin...@gmail.com>> wrote: > > > > > > Tal, > > > > > > I did a quick read of your draft. > > > > > > As noted in the draft this seems to be very similar to ICMPv6 Echo/Echo > > Reply. The change is to include the request packet in the response, not > > just the payload. > > > > > > While I don’t have any real opinion on the need for this, I do think it > > would be a lot simpler if the draft just defined a new Code field value for > > Echo Request/Reply that specified this behavior. Currently the Code field > > is set to zero, another value could specify this behavior. > > > > > > Deployment might be easier as I suspect ICMPv6 types other than the current > > definitions will be filtered in many places. > > > > > > Bob > > > > > > > > > > > > > > > On Jun 6, 2023, at 4:54 AM, Tal Mizrahi <tal.mizrahi....@gmail.com > > > <mailto:tal.mizrahi....@gmail.com>> wrote: > > > > > > Hi, > > > > > > New draft: > > > https://datatracker.ietf.org/doc/draft-mcb-intarea-icmpv6-loopback/ > > > <https://datatracker.ietf.org/doc/draft-mcb-intarea-icmpv6-loopback/> > > > > > > We have posted a new draft that proposes two new ICMPv6 message types: > > > Loopback Request and Reply. > > > ICMPv6 Loopback is very similar to Echo, except that after a Loopback > > > Request is sent, its corresponding Reply includes as much of the IPv6 > > > Loopback Request packet as possible, including the IPv6 header and > > > IPv6 extension headers and options if they are present. > > > > > > We believe that ICMPv6 Loopback can be very useful for returning IPv6 > > > options that were included in Request packet back to the sender, > > > including for example sending IOAM [RFC 9197] data from the Request > > > back to the sender, sending the SRH [RFC 8754] of the Request back to > > > the sender, as well as for in-progress / future protocols such as > > > draft-filsfils-spring-path-tracing and draft-kumar-ippm-ifa. > > > > > > We would be happy for feedback, as well as suggestions about whether > > > the INT-AREA WG is the right place to discuss this draft. > > > > > > Cheers, > > > Tal. > > > > > > _______________________________________________ > > > Int-area mailing list > > > Int-area@ietf.org <mailto:Int-area@ietf.org> > > > https://www.ietf.org/mailman/listinfo/int-area > > > <https://www.ietf.org/mailman/listinfo/int-area> > > > > > > > > > > > > -------------------------------------------------------------------- > IETF IPv6 working group mailing list > i...@ietf.org > Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 > -------------------------------------------------------------------- _______________________________________________ Int-area mailing list Int-area@ietf.org https://www.ietf.org/mailman/listinfo/int-area
