Re: Terrapin

[Sam Hartman <hartmans-ietf%mit.edu@localhost>]

>>>>> "Alexandre" == Alexandre Becoulet <alexandre.becoulet%free.fr@localhost> writes:

    Alexandre> Niels Möller wrote:

    >> One subtlety if resetting sequence number to zero is that it
    >> risks breaking MSG_UNIMPLEMENTED (since seqno may get ambiguous
    >> in some cases, e.g., if for some reason there are multiple
    >> keyexchanges only few packets apart). So please keep this in
    >> mind.


So, I think what you are saying is that  if msg_unimplemented is sent
under a different key (and thus sequence number space if we reset) than
the unimplemented message, then  there is ambiguity.

I.E.

client: some unknown message
client: newkeys
server: newkeys
server: msg_unimplemented

But why not just flush the pipeline of any unimplemented messages prior
to sending newkeys on the server side?
I.E. an msg_unimplemented needs to be sent under the key that the
unknown message was sent under?