Hello everyone, I am trying to design a driver that will add an IPv4 option
to every outbound IPv4 packet. I have developed a WFP callout that allows me
to inspect each IP packet as flows through the network layer. At this point
I'd like to clone the netbuffer, add the option header and recalculate the
appropriate fields. However, I am stuck at one critical area. I need to
report to the higher layers that the MTU is reduced by the size of the option
header to ensure that the finished packets do not exceed the MTU. Since an
outbound network layer callout can not see IP fragments, I am concerned that
the packet will then be fragmented, thus invalidating the header that I
applied (each option is correlated to the data in the payload). Can any of
the forum gurus give me any advice?
Thanks!