On Wed, Oct 26, 2011 at 03:53:49PM -0700, Jesse Gross wrote: > On Wed, Oct 26, 2011 at 3:36 PM, Ben Pfaff <b...@nicira.com> wrote: > > On Wed, Oct 26, 2011 at 03:34:10PM -0700, Jesse Gross wrote: > >> On Wed, Oct 26, 2011 at 2:59 PM, Ben Pfaff <b...@nicira.com> wrote: > >> > Navindra Yadav pointed out in a discussion over on an ONF issue tracker > >> > that first/later fragment isn't as useful with IPv6: the TCP/UDP port > >> > numbers aren't necessarily in the first fragment, because other > >> > intermediate extension headers can follow the fragment header. > >> > > >> > Any idea what we should do about this? > >> > >> This is always true, even for IPv4. ??You could have a fragment that is > >> split very quickly after the IP header or simply a truncated packet. > > > > I don't understand yet. ??An IP fragment is always at least 8 bytes long. > > The TCP and UDP port numbers are in the first 8 bytes of the TCP and UDP > > headers, respectively. ??So won't the first IP fragment of a complete TCP > > or UDP packet always contain the TCP and UDP port numbers? > > I suppose that's true but the way that we parse headers unless you > have the entire L4 header we won't read any of it. Also, clearly a > packet can be truncated at any point. > > Regardless, I think my main point stands which is that we're simply > reporting what is there and it's up to the controller to make a > decision on what to do with a first fragment with no L4 header. We > will report it as EtherType=IPv6, frag=first, nexthdr=NEXTDR_NONE so > all of the information is there.
Fair enough. _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
