1/*
2 * INET		An implementation of the TCP/IP protocol suite for the LINUX
3 *		operating system.  NET  is implemented using the  BSD Socket
4 *		interface as the means of communication with the user level.
5 *
6 *		Definitions for the Ethernet handlers.
7 *
8 * Version:	@(#)eth.h	1.0.4	05/13/93
9 *
10 * Authors:	Ross Biro
11 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 *
13 *		Relocated to include/linux where it belongs by Alan Cox
14 *							<gw4pts@gw4pts.ampr.org>
15 *
16 *		This program is free software; you can redistribute it and/or
17 *		modify it under the terms of the GNU General Public License
18 *		as published by the Free Software Foundation; either version
19 *		2 of the License, or (at your option) any later version.
20 *
21 *	WARNING: This move may well be temporary. This file will get merged with others RSN.
22 *
23 */
24#ifndef _LINUX_ETHERDEVICE_H
25#define _LINUX_ETHERDEVICE_H
26
27#include <linux/if_ether.h>
28#include <linux/netdevice.h>
29#include <linux/random.h>
30
31#ifdef __KERNEL__
32extern int		eth_header(struct sk_buff *skb, struct net_device *dev,
33				   unsigned short type, void *daddr,
34				   void *saddr, unsigned len);
35extern int		eth_rebuild_header(struct sk_buff *skb);
36extern __be16		eth_type_trans(struct sk_buff *skb, struct net_device *dev);
37extern void		eth_header_cache_update(struct hh_cache *hh, struct net_device *dev,
38						unsigned char * haddr);
39extern int		eth_header_cache(struct neighbour *neigh,
40					 struct hh_cache *hh);
41
42extern struct net_device *alloc_etherdev(int sizeof_priv);
43static inline void eth_copy_and_sum (struct sk_buff *dest,
44				     const unsigned char *src,
45				     int len, int base)
46{
47	memcpy (dest->data, src, len);
48}
49
50/**
51 * is_zero_ether_addr - Determine if give Ethernet address is all zeros.
52 * @addr: Pointer to a six-byte array containing the Ethernet address
53 *
54 * Return true if the address is all zeroes.
55 */
56static inline int is_zero_ether_addr(const u8 *addr)
57{
58	return !(addr[0] | addr[1] | addr[2] | addr[3] | addr[4] | addr[5]);
59}
60
61/**
62 * is_multicast_ether_addr - Determine if the Ethernet address is a multicast.
63 * @addr: Pointer to a six-byte array containing the Ethernet address
64 *
65 * Return true if the address is a multicast address.
66 * By definition the broadcast address is also a multicast address.
67 */
68static inline int is_multicast_ether_addr(const u8 *addr)
69{
70	return (0x01 & addr[0]);
71}
72
73/**
74 * is_broadcast_ether_addr - Determine if the Ethernet address is broadcast
75 * @addr: Pointer to a six-byte array containing the Ethernet address
76 *
77 * Return true if the address is the broadcast address.
78 */
79static inline int is_broadcast_ether_addr(const u8 *addr)
80{
81	return (addr[0] & addr[1] & addr[2] & addr[3] & addr[4] & addr[5]) == 0xff;
82}
83
84/**
85 * is_valid_ether_addr - Determine if the given Ethernet address is valid
86 * @addr: Pointer to a six-byte array containing the Ethernet address
87 *
88 * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not
89 * a multicast address, and is not FF:FF:FF:FF:FF:FF.
90 *
91 * Return true if the address is valid.
92 */
93static inline int is_valid_ether_addr(const u8 *addr)
94{
95	/* FF:FF:FF:FF:FF:FF is a multicast address so we don't need to
96	 * explicitly check for it here. */
97	return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr);
98}
99
100/**
101 * random_ether_addr - Generate software assigned random Ethernet address
102 * @addr: Pointer to a six-byte array containing the Ethernet address
103 *
104 * Generate a random Ethernet address (MAC) that is not multicast
105 * and has the local assigned bit set.
106 */
107static inline void random_ether_addr(u8 *addr)
108{
109	get_random_bytes (addr, ETH_ALEN);
110	addr [0] &= 0xfe;	/* clear multicast bit */
111	addr [0] |= 0x02;	/* set local assignment bit (IEEE802) */
112}
113
114/**
115 * compare_ether_addr - Compare two Ethernet addresses
116 * @addr1: Pointer to a six-byte array containing the Ethernet address
117 * @addr2: Pointer other six-byte array containing the Ethernet address
118 *
119 * Compare two ethernet addresses, returns 0 if equal
120 */
121static inline unsigned compare_ether_addr(const u8 *addr1, const u8 *addr2)
122{
123	const u16 *a = (const u16 *) addr1;
124	const u16 *b = (const u16 *) addr2;
125
126	BUILD_BUG_ON(ETH_ALEN != 6);
127	return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) != 0;
128}
129#endif	/* __KERNEL__ */
130
131#endif	/* _LINUX_ETHERDEVICE_H */
132