> On Dec 6, 2018, at 2:59 AM, Ole Troan <[email protected]> wrote:
>
> Joe,
>
> I think you misunderstand.
Read this text. Tell me what part of it you do not understand regarding nodes
THAT DO NOT SUPPORT an option (if “skipping over” isn’t not supported, then
what is it?):
The Option Type identifiers are internally encoded such that their
highest-order 2 bits specify the action that must be taken if the processing
IPv6 node does not recognize the Option Type:
00 - skip over this option and continue processing the header.
** 01 - discard the packet.
** 10 - discard the packet and, regardless of whether or not the packet's
Destination Address was a multicast address, send an ICMP Parameter Problem,
Code 2, message to the packet's Source Address, pointing to the unrecognized
Option Type.
** 11 - discard the packet and, only if the packet's Destination Address was
not a multicast address, send an ICMP Parameter Problem, Code 2, message to the
packet's Source Address, pointing to the unrecognized Option Type.
>> I’m talking about a conflict in the text of 8200 - which has those fields as
>> required to support - and 7045, which says they can be silently ignored.
>
> 8200 says:
> If the router is explicitly configured to process the HBH header it MUST
> adhere to the option flag 2 high order bits.
> Otherwise it MUST forward the packet.
>
> There is no conflict.
The conflict is in the issue of “not supported”. Skipping over headers means
they’re not supported, but it’s not possible to “NOT SUPPORT” them two
different ways - one silent, one that *requires* action.
Joe
_______________________________________________
OPSEC mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/opsec
