• Herbert Xu's avatar
    [NET]: Allow forwarding of ip_summed except CHECKSUM_COMPLETE · 35fc92a9
    Herbert Xu authored
    Right now Xen has a horrible hack that lets it forward packets with
    partial checksums.  One of the reasons that CHECKSUM_PARTIAL and
    CHECKSUM_COMPLETE were added is so that we can get rid of this hack
    (where it creates two extra bits in the skbuff to essentially mirror
    ip_summed without being destroyed by the forwarding code).
    I had forgotten that I've already gone through all the deivce drivers
    last time around to make sure that they're looking at ip_summed ==
    CHECKSUM_PARTIAL rather than ip_summed != 0 on transmit.  In any case,
    I've now done that again so it should definitely be safe.
    Unfortunately nobody has yet added any code to update CHECKSUM_COMPLETE
    values on forward so we I'm setting that to CHECKSUM_NONE.  This should
    be safe to remove for bridging but I'd like to check that code path
    So here is the patch that lets us get rid of the hack by preserving
    ip_summed (mostly) on forwarded packets.
    Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>