Hi!
Am Donnerstag 19 Juni 2025 um 10:48:53 +1000, schrieb David Gwynne 2,5K:
> you should be able to use tcpdump on your box to see the packets
> coming from the linux host. if you can find which interface the
> tunnel packets are entering the system with, then you should be
> able to catch some.
As far as I was able to observe, there are no packets coming in on vio0
/ gre0 - but I'll verify this evening.
> the only reason they would be sending an ipv6 destination options
> header is if they're using some mobile ipv6 semantics to send a
> Home Address option. OpenBSD does not implement support for the
> Home Address option, so we drop the packet before we get to the GRE
> input processing.
>
> the only other options specified for an ipv6 destination option header
> is for padding, and we do support that.
Tasillo from Freetransit replied the following, quoting verbatim:
"The relevant destination option that is being sent is the Tunnel
Encapsulation Limit, which is part of the GRE6 specification
(https://www.rfc-editor.org/rfc/rfc2473.html#section-6.6).
I would consider not processing that a bug in openbsd."
I'm in no position to judge his statement, regarding a possible bug,
especially since this is a little above my head ATM...
> can your provider disable that feature on their end?
They're looking for a knob :-)
--
Mit besten Wünschen /
With best wishes,
Manuel Kuklinski
