blob: f16a01081e150035438dfc886d15943a79085a00 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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 *
Jesper Juhl02c30a82005-05-05 16:16:16 -070010 * Authors: Ross Biro
Linus Torvalds1da177e2005-04-16 15:20:36 -070011 * 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>
Arnd Bergmannbcd61272005-06-28 15:58:50 -070028#include <linux/netdevice.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#include <linux/random.h>
Eric Dumazet1f87e232008-11-23 23:24:32 -080030#include <asm/unaligned.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
32#ifdef __KERNEL__
Alexey Dobriyanab611482005-07-12 12:08:43 -070033extern __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev);
Stephen Hemminger3b04ddd2007-10-09 01:40:57 -070034extern const struct header_ops eth_header_ops;
35
36extern int eth_header(struct sk_buff *skb, struct net_device *dev,
37 unsigned short type,
38 const void *daddr, const void *saddr, unsigned len);
39extern int eth_rebuild_header(struct sk_buff *skb);
40extern int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr);
41extern int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh);
42extern void eth_header_cache_update(struct hh_cache *hh,
43 const struct net_device *dev,
44 const unsigned char *haddr);
Stephen Hemmingerccad6372008-11-19 22:42:31 -080045extern int eth_mac_addr(struct net_device *dev, void *p);
46extern int eth_change_mtu(struct net_device *dev, int new_mtu);
47extern int eth_validate_addr(struct net_device *dev);
48
Stephen Hemminger3b04ddd2007-10-09 01:40:57 -070049
Linus Torvalds1da177e2005-04-16 15:20:36 -070050
Peter P Waskiewicz Jrf25f4e42007-07-06 13:36:20 -070051extern struct net_device *alloc_etherdev_mq(int sizeof_priv, unsigned int queue_count);
52#define alloc_etherdev(sizeof_priv) alloc_etherdev_mq(sizeof_priv, 1)
Linus Torvalds1da177e2005-04-16 15:20:36 -070053
54/**
Stephen Hemmingerc2da8ac2005-11-01 17:05:09 -080055 * is_zero_ether_addr - Determine if give Ethernet address is all zeros.
56 * @addr: Pointer to a six-byte array containing the Ethernet address
57 *
58 * Return true if the address is all zeroes.
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 */
60static inline int is_zero_ether_addr(const u8 *addr)
61{
62 return !(addr[0] | addr[1] | addr[2] | addr[3] | addr[4] | addr[5]);
63}
64
65/**
Stephen Hemmingerc2da8ac2005-11-01 17:05:09 -080066 * is_multicast_ether_addr - Determine if the Ethernet address is a multicast.
Michael Ellerman791651212005-05-29 20:24:30 -070067 * @addr: Pointer to a six-byte array containing the Ethernet address
68 *
69 * Return true if the address is a multicast address.
Stephen Hemminger88df8ef2006-01-03 15:25:45 -080070 * By definition the broadcast address is also a multicast address.
Michael Ellerman791651212005-05-29 20:24:30 -070071 */
72static inline int is_multicast_ether_addr(const u8 *addr)
73{
Eric Dumazeta02cec22010-09-22 20:43:57 +000074 return 0x01 & addr[0];
Michael Ellerman791651212005-05-29 20:24:30 -070075}
76
Stephen Hemmingerc2da8ac2005-11-01 17:05:09 -080077/**
Randy Dunlapbc2cda12008-02-13 15:03:25 -080078 * is_local_ether_addr - Determine if the Ethernet address is locally-assigned one (IEEE 802).
Paolo 'Blaisorblade' Giarrussoe0247152007-05-06 14:51:13 -070079 * @addr: Pointer to a six-byte array containing the Ethernet address
80 *
81 * Return true if the address is a local address.
82 */
83static inline int is_local_ether_addr(const u8 *addr)
84{
Eric Dumazeta02cec22010-09-22 20:43:57 +000085 return 0x02 & addr[0];
Paolo 'Blaisorblade' Giarrussoe0247152007-05-06 14:51:13 -070086}
87
88/**
Stephen Hemmingerc2da8ac2005-11-01 17:05:09 -080089 * is_broadcast_ether_addr - Determine if the Ethernet address is broadcast
90 * @addr: Pointer to a six-byte array containing the Ethernet address
91 *
92 * Return true if the address is the broadcast address.
93 */
Jeff Garzik9bd481f2005-06-28 01:46:35 -040094static inline int is_broadcast_ether_addr(const u8 *addr)
95{
Stephen Hemminger24075342005-11-01 16:52:11 -080096 return (addr[0] & addr[1] & addr[2] & addr[3] & addr[4] & addr[5]) == 0xff;
Jeff Garzik9bd481f2005-06-28 01:46:35 -040097}
98
Michael Ellerman791651212005-05-29 20:24:30 -070099/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100 * is_valid_ether_addr - Determine if the given Ethernet address is valid
101 * @addr: Pointer to a six-byte array containing the Ethernet address
102 *
103 * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not
Michael Ellerman791651212005-05-29 20:24:30 -0700104 * a multicast address, and is not FF:FF:FF:FF:FF:FF.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105 *
106 * Return true if the address is valid.
107 */
108static inline int is_valid_ether_addr(const u8 *addr)
109{
Michael Ellerman791651212005-05-29 20:24:30 -0700110 /* FF:FF:FF:FF:FF:FF is a multicast address so we don't need to
111 * explicitly check for it here. */
112 return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113}
114
115/**
116 * random_ether_addr - Generate software assigned random Ethernet address
117 * @addr: Pointer to a six-byte array containing the Ethernet address
118 *
119 * Generate a random Ethernet address (MAC) that is not multicast
120 * and has the local assigned bit set.
121 */
122static inline void random_ether_addr(u8 *addr)
123{
124 get_random_bytes (addr, ETH_ALEN);
125 addr [0] &= 0xfe; /* clear multicast bit */
126 addr [0] |= 0x02; /* set local assignment bit (IEEE802) */
127}
Stephen Hemminger360ac8e2005-10-25 15:03:41 -0700128
129/**
Stefan Assmannc1f79422010-07-22 02:50:21 +0000130 * dev_hw_addr_random - Create random MAC and set device flag
131 * @dev: pointer to net_device structure
Randy Dunlap7ed24e82010-08-09 13:40:03 +0000132 * @hwaddr: Pointer to a six-byte array containing the Ethernet address
Stefan Assmannc1f79422010-07-22 02:50:21 +0000133 *
134 * Generate random MAC to be used by a device and set addr_assign_type
135 * so the state can be read by sysfs and be used by udev.
136 */
137static inline void dev_hw_addr_random(struct net_device *dev, u8 *hwaddr)
138{
139 dev->addr_assign_type |= NET_ADDR_RANDOM;
140 random_ether_addr(hwaddr);
141}
142
143/**
Stephen Hemminger360ac8e2005-10-25 15:03:41 -0700144 * compare_ether_addr - Compare two Ethernet addresses
145 * @addr1: Pointer to a six-byte array containing the Ethernet address
Stephen Hemmingerc2da8ac2005-11-01 17:05:09 -0800146 * @addr2: Pointer other six-byte array containing the Ethernet address
Stephen Hemminger360ac8e2005-10-25 15:03:41 -0700147 *
148 * Compare two ethernet addresses, returns 0 if equal
149 */
Stephen Hemmingerc2da8ac2005-11-01 17:05:09 -0800150static inline unsigned compare_ether_addr(const u8 *addr1, const u8 *addr2)
Stephen Hemminger360ac8e2005-10-25 15:03:41 -0700151{
Stephen Hemmingerc2da8ac2005-11-01 17:05:09 -0800152 const u16 *a = (const u16 *) addr1;
153 const u16 *b = (const u16 *) addr2;
Stephen Hemminger360ac8e2005-10-25 15:03:41 -0700154
155 BUILD_BUG_ON(ETH_ALEN != 6);
156 return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) != 0;
157}
Eric Dumazet1f87e232008-11-23 23:24:32 -0800158
159static inline unsigned long zap_last_2bytes(unsigned long value)
160{
161#ifdef __BIG_ENDIAN
162 return value >> 16;
163#else
164 return value << 16;
165#endif
166}
167
168/**
169 * compare_ether_addr_64bits - Compare two Ethernet addresses
170 * @addr1: Pointer to an array of 8 bytes
171 * @addr2: Pointer to an other array of 8 bytes
172 *
173 * Compare two ethernet addresses, returns 0 if equal.
174 * Same result than "memcmp(addr1, addr2, ETH_ALEN)" but without conditional
175 * branches, and possibly long word memory accesses on CPU allowing cheap
176 * unaligned memory reads.
177 * arrays = { byte1, byte2, byte3, byte4, byte6, byte7, pad1, pad2}
178 *
179 * Please note that alignment of addr1 & addr2 is only guaranted to be 16 bits.
180 */
181
182static inline unsigned compare_ether_addr_64bits(const u8 addr1[6+2],
183 const u8 addr2[6+2])
184{
185#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
186 unsigned long fold = ((*(unsigned long *)addr1) ^
187 (*(unsigned long *)addr2));
188
189 if (sizeof(fold) == 8)
190 return zap_last_2bytes(fold) != 0;
191
192 fold |= zap_last_2bytes((*(unsigned long *)(addr1 + 4)) ^
193 (*(unsigned long *)(addr2 + 4)));
194 return fold != 0;
195#else
196 return compare_ether_addr(addr1, addr2);
197#endif
198}
Jiri Pirkof001fde2009-05-05 02:48:28 +0000199
200/**
201 * is_etherdev_addr - Tell if given Ethernet address belongs to the device.
202 * @dev: Pointer to a device structure
203 * @addr: Pointer to a six-byte array containing the Ethernet address
204 *
205 * Compare passed address with all addresses of the device. Return true if the
206 * address if one of the device addresses.
207 *
208 * Note that this function calls compare_ether_addr_64bits() so take care of
209 * the right padding.
210 */
211static inline bool is_etherdev_addr(const struct net_device *dev,
212 const u8 addr[6 + 2])
213{
214 struct netdev_hw_addr *ha;
215 int res = 1;
216
217 rcu_read_lock();
218 for_each_dev_addr(dev, ha) {
219 res = compare_ether_addr_64bits(addr, ha->addr);
220 if (!res)
221 break;
222 }
223 rcu_read_unlock();
224 return !res;
225}
Michael Ellerman791651212005-05-29 20:24:30 -0700226#endif /* __KERNEL__ */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227
Herbert Xuaa4b9f52009-02-08 18:00:37 +0000228/**
229 * compare_ether_header - Compare two Ethernet headers
230 * @a: Pointer to Ethernet header
231 * @b: Pointer to Ethernet header
232 *
233 * Compare two ethernet headers, returns 0 if equal.
234 * This assumes that the network header (i.e., IP header) is 4-byte
235 * aligned OR the platform can handle unaligned access. This is the
236 * case for all packets coming into netif_receive_skb or similar
237 * entry points.
238 */
239
Eric Dumazet40d08022010-08-26 22:03:08 -0700240static inline unsigned long compare_ether_header(const void *a, const void *b)
Herbert Xuaa4b9f52009-02-08 18:00:37 +0000241{
Eric Dumazet40d08022010-08-26 22:03:08 -0700242#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
243 unsigned long fold;
244
245 /*
246 * We want to compare 14 bytes:
247 * [a0 ... a13] ^ [b0 ... b13]
248 * Use two long XOR, ORed together, with an overlap of two bytes.
249 * [a0 a1 a2 a3 a4 a5 a6 a7 ] ^ [b0 b1 b2 b3 b4 b5 b6 b7 ] |
250 * [a6 a7 a8 a9 a10 a11 a12 a13] ^ [b6 b7 b8 b9 b10 b11 b12 b13]
251 * This means the [a6 a7] ^ [b6 b7] part is done two times.
252 */
253 fold = *(unsigned long *)a ^ *(unsigned long *)b;
254 fold |= *(unsigned long *)(a + 6) ^ *(unsigned long *)(b + 6);
255 return fold;
256#else
Herbert Xuaa4b9f52009-02-08 18:00:37 +0000257 u32 *a32 = (u32 *)((u8 *)a + 2);
258 u32 *b32 = (u32 *)((u8 *)b + 2);
259
260 return (*(u16 *)a ^ *(u16 *)b) | (a32[0] ^ b32[0]) |
261 (a32[1] ^ b32[1]) | (a32[2] ^ b32[2]);
Eric Dumazet40d08022010-08-26 22:03:08 -0700262#endif
Herbert Xuaa4b9f52009-02-08 18:00:37 +0000263}
264
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265#endif /* _LINUX_ETHERDEVICE_H */