1 files changed, 66 insertions, 0 deletions
diff --git a/src/include/ipxe/ethernet.h b/src/include/ipxe/ethernet.h
index 5799092a2..7e49655a3 100644
--- a/src/include/ipxe/ethernet.h
+++ b/src/include/ipxe/ethernet.h
@@ -11,6 +11,72 @@ FILE_LICENCE ( GPL2_OR_LATER );
 
 #include <stdint.h>
 
+/**
+ * Check if Ethernet address is all zeroes
+ *
+ * @v addr		Ethernet address
+ * @ret is_zero		Address is all zeroes
+ */
+static inline int is_zero_ether_addr ( const void *addr ) {
+	const uint8_t *addr_bytes = addr;
+
+	return ( ! ( addr_bytes[0] | addr_bytes[1] | addr_bytes[2] |
+		     addr_bytes[3] | addr_bytes[4] | addr_bytes[5] ) );
+}
+
+/**
+ * Check if Ethernet address is a multicast address
+ *
+ * @v addr		Ethernet address
+ * @ret is_mcast	Address is a multicast address
+ *
+ * Note that the broadcast address is also a multicast address.
+ */
+static inline int is_multicast_ether_addr ( const void *addr ) {
+	const uint8_t *addr_bytes = addr;
+
+	return ( addr_bytes[0] & 0x01 );
+}
+
+/**
+ * Check if Ethernet address is locally assigned
+ *
+ * @v addr		Ethernet address
+ * @ret is_local	Address is locally assigned
+ */
+static inline int is_local_ether_addr ( const void *addr ) {
+	const uint8_t *addr_bytes = addr;
+
+	return ( addr_bytes[0] & 0x02 );
+}
+
+/**
+ * Check if Ethernet address is the broadcast address
+ *
+ * @v addr		Ethernet address
+ * @ret is_bcast	Address is the broadcast address
+ */
+static inline int is_broadcast_ether_addr ( const void *addr ) {
+	const uint8_t *addr_bytes = addr;
+
+	return ( ( addr_bytes[0] & addr_bytes[1] & addr_bytes[2] &
+		   addr_bytes[3] & addr_bytes[4] & addr_bytes[5] ) == 0xff );
+}
+
+/**
+ * Check if Ethernet address is valid
+ *
+ * @v addr		Ethernet address
+ * @ret is_valid	Address is valid
+ *
+ * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is
+ * not a multicast address, and is not ff:ff:ff:ff:ff:ff.
+ */
+static inline int is_valid_ether_addr ( const void *addr ) {
+	return ( ( ! is_multicast_ether_addr ( addr ) ) &&
+		 ( ! is_zero_ether_addr ( addr ) ) );
+}
+
 extern void eth_init_addr ( const void *hw_addr, void *ll_addr );
 extern const char * eth_ntoa ( const void *ll_addr );
 extern int eth_mc_hash ( unsigned int af, const void *net_addr,