• Sven Eckelmann's avatar
    batman-adv: Calculate correct size for merged packets · ae361ce1
    Sven Eckelmann authored
    The routing algorithm must be able to decide if a fragment can be merged with
    the missing part and still be passed to a forwarding interface. The fragments
    can only differ by one byte in case that the original payload had an uneven
    length. In that situation the sender has to inform all possible receivers that
    the tail is one byte longer using the flag UNI_FRAG_LARGETAIL.
    
    The combination of UNI_FRAG_LARGETAIL and UNI_FRAG_HEAD flag makes it possible
    to calculate the correct length for even and uneven sized payloads.
    
    The original formula missed to add the unicast header at all and forgot to
    remove the fragment header of the second fragment. This made the results highly
    unreliable and only useful for machines with large differences between the
    configured MTUs.
    Reported-by: default avatarRussell Senior <russell@personaltelco.net>
    Reported-by: default avatarMarek Lindner <lindner_marek@yahoo.de>
    Signed-off-by: default avatarSven Eckelmann <sven@narfation.org>
    ae361ce1
packet.h 3.66 KB