(((c) & 0xff) << 8) | \
((d) & 0xff))
+/** Internet header length mask for version_ihl field */
+#define IPV4_HDR_IHL_MASK (0x0f)
+/**
+ * Internet header length field multiplier (IHL field specifies overall header
+ * length in number of 4-byte words)
+ */
+#define IPV4_IHL_MULTIPLIER (4)
+
/* Fragment Offset * Flags. */
#define IPV4_HDR_DF_SHIFT 14
#define IPV4_HDR_MF_SHIFT 13