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.
6 * Definitions for the Ethernet handlers.
8 * Version: @(#)eth.h 1.0.4 05/13/93
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
13 * Relocated to include/linux where it belongs by Alan Cox
14 * <gw4pts@gw4pts.ampr.org>
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.
21 * WARNING: This move may well be temporary. This file will get merged with others RSN.
24 #ifndef _LINUX_ETHERDEVICE_H
25 #define _LINUX_ETHERDEVICE_H
27 #include <linux/if_ether.h>
28 #include <linux/netdevice.h>
29 #include <linux/random.h>
32 extern int eth_header(struct sk_buff *skb, struct net_device *dev,
33 unsigned short type, void *daddr,
34 void *saddr, unsigned len);
35 extern int eth_rebuild_header(struct sk_buff *skb);
36 extern __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev);
37 extern void eth_header_cache_update(struct hh_cache *hh, struct net_device *dev,
38 unsigned char * haddr);
39 extern int eth_header_cache(struct neighbour *neigh,
42 extern struct net_device *alloc_etherdev(int sizeof_priv);
45 * is_zero_ether_addr - Determine if give Ethernet address is all zeros.
46 * @addr: Pointer to a six-byte array containing the Ethernet address
48 * Return true if the address is all zeroes.
50 static inline int is_zero_ether_addr(const u8 *addr)
52 return !(addr[0] | addr[1] | addr[2] | addr[3] | addr[4] | addr[5]);
56 * is_multicast_ether_addr - Determine if the Ethernet address is a multicast.
57 * @addr: Pointer to a six-byte array containing the Ethernet address
59 * Return true if the address is a multicast address.
60 * By definition the broadcast address is also a multicast address.
62 static inline int is_multicast_ether_addr(const u8 *addr)
64 return (0x01 & addr[0]);
68 * is_local_ether_addr - Determine if the Ethernet address is locally-assigned
70 * @addr: Pointer to a six-byte array containing the Ethernet address
72 * Return true if the address is a local address.
74 static inline int is_local_ether_addr(const u8 *addr)
76 return (0x02 & addr[0]);
80 * is_broadcast_ether_addr - Determine if the Ethernet address is broadcast
81 * @addr: Pointer to a six-byte array containing the Ethernet address
83 * Return true if the address is the broadcast address.
85 static inline int is_broadcast_ether_addr(const u8 *addr)
87 return (addr[0] & addr[1] & addr[2] & addr[3] & addr[4] & addr[5]) == 0xff;
91 * is_valid_ether_addr - Determine if the given Ethernet address is valid
92 * @addr: Pointer to a six-byte array containing the Ethernet address
94 * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not
95 * a multicast address, and is not FF:FF:FF:FF:FF:FF.
97 * Return true if the address is valid.
99 static inline int is_valid_ether_addr(const u8 *addr)
101 /* FF:FF:FF:FF:FF:FF is a multicast address so we don't need to
102 * explicitly check for it here. */
103 return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr);
107 * random_ether_addr - Generate software assigned random Ethernet address
108 * @addr: Pointer to a six-byte array containing the Ethernet address
110 * Generate a random Ethernet address (MAC) that is not multicast
111 * and has the local assigned bit set.
113 static inline void random_ether_addr(u8 *addr)
115 get_random_bytes (addr, ETH_ALEN);
116 addr [0] &= 0xfe; /* clear multicast bit */
117 addr [0] |= 0x02; /* set local assignment bit (IEEE802) */
121 * compare_ether_addr - Compare two Ethernet addresses
122 * @addr1: Pointer to a six-byte array containing the Ethernet address
123 * @addr2: Pointer other six-byte array containing the Ethernet address
125 * Compare two ethernet addresses, returns 0 if equal
127 static inline unsigned compare_ether_addr(const u8 *addr1, const u8 *addr2)
129 const u16 *a = (const u16 *) addr1;
130 const u16 *b = (const u16 *) addr2;
132 BUILD_BUG_ON(ETH_ALEN != 6);
133 return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) != 0;
135 #endif /* __KERNEL__ */
137 #endif /* _LINUX_ETHERDEVICE_H */