diff --git a/libc/include/net/ethernet.h b/libc/include/net/ethernet.h
index 47858b3..d5ba11f 100644
--- a/libc/include/net/ethernet.h
+++ b/libc/include/net/ethernet.h
@@ -29,7 +29,52 @@
 #ifndef _NET_ETHERNET_H_
 #define _NET_ETHERNET_H_
 
+#include <sys/cdefs.h>
+#include <sys/types.h>
+
 #include <linux/if_ether.h>
-#include <net/if_ether.h>
+
+#define ETHERTYPE_IP 0x0800
+#define ETHERTYPE_ARP 0x0806
+#define ETHERTYPE_REVARP 0x8035
+#define ETHERTYPE_VLAN 0x8100
+#define ETHERTYPE_IPX 0x8137
+#define ETHERTYPE_IPV6 0x86dd
+#define ETHERTYPE_LOOPBACK 0x9000
+
+#define ETHERTYPE_TRAIL 0x1000
+#define ETHERTYPE_NTRAILER 16
+
+/*
+ * Some basic Ethernet constants.
+ */
+#define	ETHER_ADDR_LEN	6	/* length of an Ethernet address */
+#define	ETHER_TYPE_LEN	2	/* length of the Ethernet type field */
+#define	ETHER_CRC_LEN	4	/* length of the Ethernet CRC */
+#define	ETHER_HDR_LEN	((ETHER_ADDR_LEN * 2) + ETHER_TYPE_LEN)
+#define	ETHER_MIN_LEN	64	/* minimum frame length, including CRC */
+#define	ETHER_MAX_LEN	1518	/* maximum frame length, including CRC */
+#define	ETHER_MAX_LEN_JUMBO 9018 /* maximum jumbo frame len, including CRC */
+
+/*
+ * Ethernet address - 6 octets
+ * this is only used by the ethers(3) functions.
+ */
+struct ether_addr {
+	u_int8_t ether_addr_octet[ETHER_ADDR_LEN];
+} __attribute__((__packed__));
+
+/*
+ * Structure of a 10Mb/s Ethernet header.
+ */
+struct	ether_header {
+	u_int8_t  ether_dhost[ETHER_ADDR_LEN];
+	u_int8_t  ether_shost[ETHER_ADDR_LEN];
+	u_int16_t ether_type;
+} __attribute__((__packed__));
+
+#define	ETHERMTU_JUMBO	(ETHER_MAX_LEN_JUMBO - ETHER_HDR_LEN - ETHER_CRC_LEN)
+#define	ETHERMTU	(ETHER_MAX_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
+#define	ETHERMIN	(ETHER_MIN_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
 
 #endif