summaryrefslogtreecommitdiffstats
path: root/include/linux/etherdevice.h
blob: 848480bc2bf93846b14e43c0c94493cb2109f889 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
/*
 * INET		An implementation of the TCP/IP protocol suite for the LINUX
 *		operating system.  NET  is implemented using the  BSD Socket
 *		interface as the means of communication with the user level.
 *
 *		Definitions for the Ethernet handlers.
 *
 * Version:	@(#)eth.h	1.0.4	05/13/93
 *
 * Authors:	Ross Biro
 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *
 *		Relocated to include/linux where it belongs by Alan Cox 
 *							<gw4pts@gw4pts.ampr.org>
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 *	WARNING: This move may well be temporary. This file will get merged with others RSN.
 *
 */
#ifndef _LINUX_ETHERDEVICE_H
#define _LINUX_ETHERDEVICE_H

#include <linux/if_ether.h>
#include <linux/netdevice.h>
#include <linux/random.h>
#include <asm/unaligned.h>

#ifdef __KERNEL__
extern __be16		eth_type_trans(struct sk_buff *skb, struct net_device *dev);
extern const struct header_ops eth_header_ops;

extern int eth_header(struct sk_buff *skb, struct net_device *dev,
		      unsigned short type,
		      const void *daddr, const void *saddr, unsigned len);
extern int eth_rebuild_header(struct sk_buff *skb);
extern int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr);
extern int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh);
extern void eth_header_cache_update(struct hh_cache *hh,
				    const struct net_device *dev,
				    const unsigned char *haddr);
extern int eth_mac_addr(struct net_device *dev, void *p);
extern int eth_change_mtu(struct net_device *dev, int new_mtu);
extern int eth_validate_addr(struct net_device *dev);



extern struct net_device *alloc_etherdev_mq(int sizeof_priv, unsigned int queue_count);
#define alloc_etherdev(sizeof_priv) alloc_etherdev_mq(sizeof_priv, 1)

/**
 * is_zero_ether_addr - Determine if give Ethernet address is all zeros.
 * @addr: Pointer to a six-byte array containing the Ethernet address
 *
 * Return true if the address is all zeroes.
 */
static inline int is_zero_ether_addr(const u8 *addr)
{
	return !(addr[0] | addr[1] | addr[2] | addr[3] | addr[4] | addr[5]);
}

/**
 * is_multicast_ether_addr - Determine if the Ethernet address is a multicast.
 * @addr: Pointer to a six-byte array containing the Ethernet address
 *
 * Return true if the address is a multicast address.
 * By definition the broadcast address is also a multicast address.
 */
static inline int is_multicast_ether_addr(const u8 *addr)
{
	return (0x01 & addr[0]);
}

/**
 * is_local_ether_addr - Determine if the Ethernet address is locally-assigned one (IEEE 802).
 * @addr: Pointer to a six-byte array containing the Ethernet address
 *
 * Return true if the address is a local address.
 */
static inline int is_local_ether_addr(const u8 *addr)
{
	return (0x02 & addr[0]);
}

/**
 * is_broadcast_ether_addr - Determine if the Ethernet address is broadcast
 * @addr: Pointer to a six-byte array containing the Ethernet address
 *
 * Return true if the address is the broadcast address.
 */
static inline int is_broadcast_ether_addr(const u8 *addr)
{
	return (addr[0] & addr[1] & addr[2] & addr[3] & addr[4] & addr[5]) == 0xff;
}

/**
 * is_valid_ether_addr - Determine if the given Ethernet address is valid
 * @addr: Pointer to a six-byte array containing the Ethernet address
 *
 * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not
 * a multicast address, and is not FF:FF:FF:FF:FF:FF.
 *
 * Return true if the address is valid.
 */
static inline int is_valid_ether_addr(const u8 *addr)
{
	/* FF:FF:FF:FF:FF:FF is a multicast address so we don't need to
	 * explicitly check for it here. */
	return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr);
}

/**
 * random_ether_addr - Generate software assigned random Ethernet address
 * @addr: Pointer to a six-byte array containing the Ethernet address
 *
 * Generate a random Ethernet address (MAC) that is not multicast
 * and has the local assigned bit set.
 */
static inline void random_ether_addr(u8 *addr)
{
	get_random_bytes (addr, ETH_ALEN);
	addr [0] &= 0xfe;	/* clear multicast bit */
	addr [0] |= 0x02;	/* set local assignment bit (IEEE802) */
}

/**
 * dev_hw_addr_random - Create random MAC and set device flag
 * @dev: pointer to net_device structure
 * @addr: Pointer to a six-byte array containing the Ethernet address
 *
 * Generate random MAC to be used by a device and set addr_assign_type
 * so the state can be read by sysfs and be used by udev.
 */
static inline void dev_hw_addr_random(struct net_device *dev, u8 *hwaddr)
{
	dev->addr_assign_type |= NET_ADDR_RANDOM;
	random_ether_addr(hwaddr);
}

/**
 * compare_ether_addr - Compare two Ethernet addresses
 * @addr1: Pointer to a six-byte array containing the Ethernet address
 * @addr2: Pointer other six-byte array containing the Ethernet address
 *
 * Compare two ethernet addresses, returns 0 if equal
 */
static inline unsigned compare_ether_addr(const u8 *addr1, const u8 *addr2)
{
	const u16 *a = (const u16 *) addr1;
	const u16 *b = (const u16 *) addr2;

	BUILD_BUG_ON(ETH_ALEN != 6);
	return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) != 0;
}

static inline unsigned long zap_last_2bytes(unsigned long value)
{
#ifdef __BIG_ENDIAN
	return value >> 16;
#else
	return value << 16;
#endif
}

/**
 * compare_ether_addr_64bits - Compare two Ethernet addresses
 * @addr1: Pointer to an array of 8 bytes
 * @addr2: Pointer to an other array of 8 bytes
 *
 * Compare two ethernet addresses, returns 0 if equal.
 * Same result than "memcmp(addr1, addr2, ETH_ALEN)" but without conditional
 * branches, and possibly long word memory accesses on CPU allowing cheap
 * unaligned memory reads.
 * arrays = { byte1, byte2, byte3, byte4, byte6, byte7, pad1, pad2}
 *
 * Please note that alignment of addr1 & addr2 is only guaranted to be 16 bits.
 */

static inline unsigned compare_ether_addr_64bits(const u8 addr1[6+2],
						 const u8 addr2[6+2])
{
#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
	unsigned long fold = ((*(unsigned long *)addr1) ^
			      (*(unsigned long *)addr2));

	if (sizeof(fold) == 8)
		return zap_last_2bytes(fold) != 0;

	fold |= zap_last_2bytes((*(unsigned long *)(addr1 + 4)) ^
				(*(unsigned long *)(addr2 + 4)));
	return fold != 0;
#else
	return compare_ether_addr(addr1, addr2);
#endif
}

/**
 * is_etherdev_addr - Tell if given Ethernet address belongs to the device.
 * @dev: Pointer to a device structure
 * @addr: Pointer to a six-byte array containing the Ethernet address
 *
 * Compare passed address with all addresses of the device. Return true if the
 * address if one of the device addresses.
 *
 * Note that this function calls compare_ether_addr_64bits() so take care of
 * the right padding.
 */
static inline bool is_etherdev_addr(const struct net_device *dev,
				    const u8 addr[6 + 2])
{
	struct netdev_hw_addr *ha;
	int res = 1;

	rcu_read_lock();
	for_each_dev_addr(dev, ha) {
		res = compare_ether_addr_64bits(addr, ha->addr);
		if (!res)
			break;
	}
	rcu_read_unlock();
	return !res;
}
#endif	/* __KERNEL__ */

/**
 * compare_ether_header - Compare two Ethernet headers
 * @a: Pointer to Ethernet header
 * @b: Pointer to Ethernet header
 *
 * Compare two ethernet headers, returns 0 if equal.
 * This assumes that the network header (i.e., IP header) is 4-byte
 * aligned OR the platform can handle unaligned access.  This is the
 * case for all packets coming into netif_receive_skb or similar
 * entry points.
 */

static inline int compare_ether_header(const void *a, const void *b)
{
	u32 *a32 = (u32 *)((u8 *)a + 2);
	u32 *b32 = (u32 *)((u8 *)b + 2);

	return (*(u16 *)a ^ *(u16 *)b) | (a32[0] ^ b32[0]) |
	       (a32[1] ^ b32[1]) | (a32[2] ^ b32[2]);
}

#endif	/* _LINUX_ETHERDEVICE_H */