I’m looking at some Ethernet bridging code which sits above Ethernet drivers
(an en-en filter). When the bridge doesn’t know which interface to send an
Ethernet packet to it broadcasts it to all interfaces. It does this without
any copying by using a new npkt_t for each interface and pointing them to
the same packet data. Only when all interfaces have finished with the packet
data is the original npkt released.
The problem I have is that it appears that the (big) IP stack is modifying
some of the packet data - which of course affects all other interfaces using
the same data.
Does the IP stack modify the packet contents of data passed up ?
Is there any way of stopping it ?
Thanks in advance