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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_local_ether_addr - Determine if the Ethernet address is locally-assigned
75 * one (IEEE 802).
76 * @addr: Pointer to a six-byte array containing the Ethernet address
77 *
78 * Return true if the address is a local address.
79 */
80static inline int is_local_ether_addr(const u8 *addr)
81{
82 return (0x02 & addr[0]);
83}
84
85/**
86 * is_broadcast_ether_addr - Determine if the Ethernet address is broadcast
87 * @addr: Pointer to a six-byte array containing the Ethernet address
88 *
89 * Return true if the address is the broadcast address.
90 */
91static inline int is_broadcast_ether_addr(const u8 *addr)
92{
93 return (addr[0] & addr[1] & addr[2] & addr[3] & addr[4] & addr[5]) == 0xff;
94}
95
96/**
97 * is_valid_ether_addr - Determine if the given Ethernet address is valid
98 * @addr: Pointer to a six-byte array containing the Ethernet address
99 *
100 * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not
101 * a multicast address, and is not FF:FF:FF:FF:FF:FF.
102 *
103 * Return true if the address is valid.
104 */
105static inline int is_valid_ether_addr(const u8 *addr)
106{
107 /* FF:FF:FF:FF:FF:FF is a multicast address so we don't need to
108 * explicitly check for it here. */
109 return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr);
110}
111
112/**
113 * random_ether_addr - Generate software assigned random Ethernet address
114 * @addr: Pointer to a six-byte array containing the Ethernet address
115 *
116 * Generate a random Ethernet address (MAC) that is not multicast
117 * and has the local assigned bit set.
118 */
119static inline void random_ether_addr(u8 *addr)
120{
121 get_random_bytes (addr, ETH_ALEN);
122 addr [0] &= 0xfe; /* clear multicast bit */
123 addr [0] |= 0x02; /* set local assignment bit (IEEE802) */
124}
125
126/**
127 * compare_ether_addr - Compare two Ethernet addresses
128 * @addr1: Pointer to a six-byte array containing the Ethernet address
129 * @addr2: Pointer other six-byte array containing the Ethernet address
130 *
131 * Compare two ethernet addresses, returns 0 if equal
132 */
133static inline unsigned compare_ether_addr(const u8 *addr1, const u8 *addr2)
134{
135 const u16 *a = (const u16 *) addr1;
136 const u16 *b = (const u16 *) addr2;
137
138 BUILD_BUG_ON(ETH_ALEN != 6);
139 return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) != 0;
140}
141#endif /* __KERNEL__ */
142
143#endif /* _LINUX_ETHERDEVICE_H */