Megacommit to straigthen out ETHER_ mess.

I'm pretty convinced after looking at this that the majority of our
drivers are confused about the in/exclusion of ETHER_CRC_LEN :-(

1 files changed, 56 insertions, 6 deletions

diff --git a/sys/net/ethernet.h b/sys/net/ethernet.h
index 487849e..6cd539e 100644
--- a/sys/net/ethernet.h
+++ b/sys/net/ethernet.h
@@ -1,13 +1,63 @@
 /*
  * Fundamental constants relating to ethernet.
  *
- * $Id$
+ * $Id: ethernet.h,v 1.1 1996/08/05 14:02:38 phk Exp $
  *
  */
 
+#ifndef _NET_ETHERNET_H_
+#define _NET_ETHERNET_H_
+
+/*
+ * The number of bytes in an ethernet (MAC) address.
+ */
 #define	ETHER_ADDR_LEN		6
-#define ETHER_TYPE_LEN		2
-#define	ETHER_CRC_LENGTH	4
-#define	ETHER_HDR_SIZE		(ETHER_ADDR_LEN*2+ETHER_TYPE_LEN)
-#define ETHER_MIN_LEN		64
-#define ETHER_MAX_LEN		1518
+
+/*
+ * The number of bytes in the type field.
+ */
+#define	ETHER_TYPE_LEN		2
+
+/*
+ * The number of bytes in the trailing CRC field.
+ */
+#define	ETHER_CRC_LEN		4
+
+/*
+ * The length of the combined header.
+ */
+#define	ETHER_HDR_LEN		(ETHER_ADDR_LEN*2+ETHER_TYPE_LEN)
+
+/*
+ * The minimum packet length.
+ */
+#define	ETHER_MIN_LEN		64
+
+/*
+ * The maximum packet length.
+ */
+#define	ETHER_MAX_LEN		1518
+
+/*
+ * A macro to validate a length with
+ */
+#define	ETHER_IS_VALID_LEN(foo)	\
+	((foo) >= ETHER_MIN_LEN && (foo) <= ETHER_MAX_LEN)
+
+/*
+ * Structure of a 10Mb/s Ethernet header.
+ */
+struct	ether_header {
+	u_char	ether_dhost[ETHER_ADDR_LEN];
+	u_char	ether_shost[ETHER_ADDR_LEN];
+	u_short	ether_type;
+};
+
+/*
+ * Structure of a 48-bit Ethernet address.
+ */
+struct	ether_addr {
+	u_char octet[ETHER_ADDR_LEN];
+};
+
+#endif