There have been several instances where response from kernel
has overrun the stack buffer from the caller. Avoid future problems
by passing a size argument.
Also drop the unused peer and group arguments to rtnl_talk.
Added 'ip fou...' commands to enable/disable UDP ports for doing
foo-over-udp and Generic UDP Encapsulation variant. Arguments are port
number to bind to and IP protocol to map to port (for direct FOU).
Examples:
ip fou add port 7777 gue
ip fou add port 8888 ipproto 4
The first command creates a GUE port, the second creates a direct FOU
port for IPIP (receive payload is a assumed to be an IPv4 packet).
Signed-off-by: Tom Herbert <therbert@google.com>