summaryrefslogtreecommitdiff
path: root/include/linux/etherdevice.h
blob: 2f0e3d0818bce14a700f3b01cc61364129656ef2 (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
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
/*
 * 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.
 *
 */
#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>
#include <asm/bitsperlong.h>

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

int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type,
	       const void *daddr, const void *saddr, unsigned len);
int eth_rebuild_header(struct sk_buff *skb);
int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr);
int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh,
		     __be16 type);
void eth_header_cache_update(struct hh_cache *hh, const struct net_device *dev,
			     const unsigned char *haddr);
int eth_prepare_mac_addr_change(struct net_device *dev, void *p);
void eth_commit_mac_addr_change(struct net_device *dev, void *p);
int eth_mac_addr(struct net_device *dev, void *p);
int eth_change_mtu(struct net_device *dev, int new_mtu);
int eth_validate_addr(struct net_device *dev);

struct net_device *alloc_etherdev_mqs(int sizeof_priv, unsigned int txqs,
					    unsigned int rxqs);
#define alloc_etherdev(sizeof_priv) alloc_etherdev_mq(sizeof_priv, 1)
#define alloc_etherdev_mq(sizeof_priv, count) alloc_etherdev_mqs(sizeof_priv, count, count)

/* Reserved Ethernet Addresses per IEEE 802.1Q */
static const u8 eth_reserved_addr_base[ETH_ALEN] __aligned(2) =
{ 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };

/**
 * is_link_local_ether_addr - Determine if given Ethernet address is link-local
 * @addr: Pointer to a six-byte array containing the Ethernet address
 *
 * Return true if address is link local reserved addr (01:80:c2:00:00:0X) per
 * IEEE 802.1Q 8.6.3 Frame filtering.
 */
static inline bool is_link_local_ether_addr(const u8 *addr)
{
	__be16 *a = (__be16 *)addr;
	static const __be16 *b = (const __be16 *)eth_reserved_addr_base;
	static const __be16 m = cpu_to_be16(0xfff0);

	return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | ((a[2] ^ b[2]) & m)) == 0;
}

/**
 * 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 bool 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 bool 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 bool 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 bool is_broadcast_ether_addr(const u8 *addr)
{
	return (addr[0] & addr[1] & addr[2] & addr[3] & addr[4] & addr[5]) == 0xff;
}

/**
 * is_unicast_ether_addr - Determine if the Ethernet address is unicast
 * @addr: Pointer to a six-byte array containing the Ethernet address
 *
 * Return true if the address is a unicast address.
 */
static inline bool is_unicast_ether_addr(const u8 *addr)
{
	return !is_multicast_ether_addr(addr);
}

/**
 * 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 bool 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);
}

/**
 * eth_random_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 eth_random_addr(u8 *addr)
{
	get_random_bytes(addr, ETH_ALEN);
	addr[0] &= 0xfe;	/* clear multicast bit */
	addr[0] |= 0x02;	/* set local assignment bit (IEEE802) */
}

#define random_ether_addr(addr) eth_random_addr(addr)

/**
 * eth_broadcast_addr - Assign broadcast address
 * @addr: Pointer to a six-byte array containing the Ethernet address
 *
 * Assign the broadcast address to the given address array.
 */
static inline void eth_broadcast_addr(u8 *addr)
{
	memset(addr, 0xff, ETH_ALEN);
}

/**
 * eth_zero_addr - Assign zero address
 * @addr: Pointer to a six-byte array containing the Ethernet address
 *
 * Assign the zero address to the given address array.
 */
static inline void eth_zero_addr(u8 *addr)
{
	memset(addr, 0x00, ETH_ALEN);
}

/**
 * eth_hw_addr_random - Generate software assigned random Ethernet and
 * set device flag
 * @dev: pointer to net_device structure
 *
 * Generate a random Ethernet address (MAC) to be used by a net device
 * and set addr_assign_type so the state can be read by sysfs and be
 * used by userspace.
 */
static inline void eth_hw_addr_random(struct net_device *dev)
{
	dev->addr_assign_type = NET_ADDR_RANDOM;
	eth_random_addr(dev->dev_addr);
}

/**
 * eth_hw_addr_inherit - Copy dev_addr from another net_device
 * @dst: pointer to net_device to copy dev_addr to
 * @src: pointer to net_device to copy dev_addr from
 *
 * Copy the Ethernet address from one net_device to another along with
 * the address attributes (addr_assign_type).
 */
static inline void eth_hw_addr_inherit(struct net_device *dst,
				       struct net_device *src)
{
	dst->addr_assign_type = src->addr_assign_type;
	memcpy(dst->dev_addr, src->dev_addr, ETH_ALEN);
}

/**
 * ether_addr_equal - 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 true if equal
 *
 * Please note: addr1 & addr2 must both be aligned to u16.
 */
static inline bool ether_addr_equal(const u8 *addr1, const u8 *addr2)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
	u32 fold = ((*(const u32 *)addr1) ^ (*(const u32 *)addr2)) |
		   ((*(const u16 *)(addr1 + 4)) ^ (*(const u16 *)(addr2 + 4)));

	return fold == 0;
#else
	const u16 *a = (const u16 *)addr1;
	const u16 *b = (const u16 *)addr2;

	return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) == 0;
#endif
}

/**
 * ether_addr_equal_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 true if equal, false otherwise.
 *
 * The function doesn't need any conditional branches and possibly uses
 * word memory accesses on CPU allowing cheap unaligned memory reads.
 * arrays = { byte1, byte2, byte3, byte4, byte5, byte6, pad1, pad2 }
 *
 * Please note that alignment of addr1 & addr2 are only guaranteed to be 16 bits.
 */

static inline bool ether_addr_equal_64bits(const u8 addr1[6+2],
					   const u8 addr2[6+2])
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
	u64 fold = (*(const u64 *)addr1) ^ (*(const u64 *)addr2);

#ifdef __BIG_ENDIAN
	return (fold >> 16) == 0;
#else
	return (fold << 16) == 0;
#endif
#else
	return ether_addr_equal(addr1, addr2);
#endif
}

/**
 * ether_addr_equal_unaligned - Compare two not u16 aligned 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 true if equal
 *
 * Please note: Use only when any Ethernet address may not be u16 aligned.
 */
static inline bool ether_addr_equal_unaligned(const u8 *addr1, const u8 *addr2)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
	return ether_addr_equal(addr1, addr2);
#else
	return memcmp(addr1, addr2, ETH_ALEN) == 0;
#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 ether_addr_equal_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;
	bool res = false;

	rcu_read_lock();
	for_each_dev_addr(dev, ha) {
		res = ether_addr_equal_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 unsigned long compare_ether_header(const void *a, const void *b)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
	unsigned long fold;

	/*
	 * We want to compare 14 bytes:
	 *  [a0 ... a13] ^ [b0 ... b13]
	 * Use two long XOR, ORed together, with an overlap of two bytes.
	 *  [a0  a1  a2  a3  a4  a5  a6  a7 ] ^ [b0  b1  b2  b3  b4  b5  b6  b7 ] |
	 *  [a6  a7  a8  a9  a10 a11 a12 a13] ^ [b6  b7  b8  b9  b10 b11 b12 b13]
	 * This means the [a6 a7] ^ [b6 b7] part is done two times.
	*/
	fold = *(unsigned long *)a ^ *(unsigned long *)b;
	fold |= *(unsigned long *)(a + 6) ^ *(unsigned long *)(b + 6);
	return fold;
#else
	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
}

#endif	/* _LINUX_ETHERDEVICE_H */