- uses match-grouping;\r
- \r
-// struct ofp_match match; /* Packet metadata. Variable size. */\r
-// /* The variable size and padded match is always followed by:\r
-// * - Exactly 2 all-zero padding bytes, then\r
-// * - An Ethernet frame whose length is inferred from header.length.\r
-// * The padding bytes preceding the Ethernet frame ensure that the IP\r
-// * header (if any) following the Ethernet header is 32-bit aligned.\r
-// */\r