Eric Lee / smarc-fsl-linux-kernel

15 Jul, 2010

1 commit

  • edf0e1fb0   netfilter: add CHECKSUM target ... Browse Code ยป

    This adds a `CHECKSUM' target, which can be used in the iptables mangle
    table.

    You can use this target to compute and fill in the checksum in
    a packet that lacks a checksum. This is particularly useful,
    if you need to work around old applications such as dhcp clients,
    that do not work well with checksum offloads, but don't want to
    disable checksum offload in your device.

    The problem happens in the field with virtualized applications.
    For reference, see Red Hat bz 605555, as well as
    http://www.spinics.net/lists/kvm/msg37660.html

    Typical expected use (helps old dhclient binary running in a VM):
    iptables -A POSTROUTING -t mangle -p udp --dport bootpc \
    -j CHECKSUM --checksum-fill

    Includes fixes by Jan Engelhardt

    Signed-off-by: Michael S. Tsirkin
    Signed-off-by: Patrick McHardy

    Michael S. Tsirkin