Implement the size field.

include/grub/net/ethernet.h

@@ -1,11 +1,31 @@
 #ifndef GRUB_NET_ETHERNET_HEADER
 #define GRUB_NET_ETHERNET_HEADER	1
 #include <grub/misc.h>
-struct etherhdr {
+#define LLCADDRMASK 0x7f
+
+struct etherhdr
+{
   grub_uint8_t dst[6];
   grub_uint8_t src[6];
   grub_uint16_t type;
-} __attribute__ ((packed))  ;
+} __attribute__ ((packed));
+
+#define PCP (x) x & 0xe000 
+#define CFI (x) x & 0x1000
+#define VID (x) x & 0x0fff
+
+struct llchdr
+{
+grub_uint8_t dsap;
+grub_uint8_t ssap;
+grub_uint8_t ctrl;
+} __attribute__ ((packed));
+
+struct snaphdr
+{
+grub_uint8_t oui[3]; 
+grub_uint16_t type;
+} __attribute__ ((packed));
 
 void ethernet_ini(void);
 void ethernet_fini(void);