The OpenFlow 1.0 specification supports matching the IP address and
opcode in ARP messages. The datapath already supports this, so this
commit merely exposes that through the OpenFlow module.
NOTE: OVS at this point is not wire-compatible with OpenFlow 1.0
until the final commit in this OpenFlow 1.0 set.
On some system, at least, one must include <sys/types.h> before
<netinet/in.h>, and <netinet/in.h> before <arpa/inet.h> or <net/if.h>.
From Jean Tourrilhes <jt@hpl.hp.com>.
The ability to match the IP addresses in ARP packets allows for fine-grained
control of ARP processing. Some forthcoming changes to allow in-band
control to operate over L3 requires this support if we don't want to
allow overly broad rules regarding ARPs to always be white-listed.
Unfortunately, OpenFlow does not support this sort of processing yet, so
we must treat OpenFlow ARP rules as having wildcarded those L3 fields.