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Re: Scrub and fragments



On Tue, Nov 19, 2002 at 12:27:41PM +0100, henning@cvs.openbsd.org wrote:
> come one, spend a second on it. fragmented packets with the don't fragment
> bit set are invalid. that's so obvious.
Well, there's the case where fragments can be fragmented further, the
RFCs support that. The question is whether anyone would sanely set the
DF bit on a fragment to prevent _further_ fragmentation. You have to
consider fragmentation of fragments in context of PMTU and then compare
all of this to Linux NFS setting DF on all (unfragmented) packets, and
the reasons they do that (which is not fragmentation of fragments at
all).
> notheless you can just "scrub in all no-df".
That won't work for him, as the check in question happens before no-df
is applied.
Daniel