Re: 6MAN WG Last Call:draft-ietf-6man-overlap-fragment-01.txt

[Thomas Narten <narten at us.ibm.com>]

Vishwas Manral <vishwas.ietf at gmail.com> writes:

> Hi Christian,

> Ok. I think to make it more generic we can call it a middlebox instead
> of a firewall alone.

> The text could be :

> "IPv6 nodes or middleboxes that receive a fragment that overlaps with
> a previously received fragment MUST cease the reassembly process and
> MUST discard the previously received fragments  with the same IPv6
> Source Address, IPv6 Destination Address and Fragment
> Identification."

Except now it can be read to apply to devices that shouldn't be
required to do this, i.e., those that are not attempting to reassemble
anything...

How about something like:

    When reassembling an IPv6 datagram, if one or more its constituent
    fragments is determined to be an overlapping fragment, the entire
    datagram (and any constituent fragments -- including those not yet
    received), MUST be silently discarded.

Thomas