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v5.9
  1/* SPDX-License-Identifier: GPL-2.0-or-later */
  2/*
  3 * INET		An implementation of the TCP/IP protocol suite for the LINUX
  4 *		operating system.  NET  is implemented using the  BSD Socket
  5 *		interface as the means of communication with the user level.
  6 *
  7 *		Definitions for the Ethernet handlers.
  8 *
  9 * Version:	@(#)eth.h	1.0.4	05/13/93
 10 *
 11 * Authors:	Ross Biro
 12 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 13 *
 14 *		Relocated to include/linux where it belongs by Alan Cox 
 15 *							<gw4pts@gw4pts.ampr.org>
 
 
 
 
 
 
 
 
 16 */
 17#ifndef _LINUX_ETHERDEVICE_H
 18#define _LINUX_ETHERDEVICE_H
 19
 20#include <linux/if_ether.h>
 21#include <linux/netdevice.h>
 22#include <linux/random.h>
 23#include <linux/crc32.h>
 24#include <asm/unaligned.h>
 25#include <asm/bitsperlong.h>
 26
 27#ifdef __KERNEL__
 28struct device;
 29int eth_platform_get_mac_address(struct device *dev, u8 *mac_addr);
 30unsigned char *arch_get_platform_mac_address(void);
 31int nvmem_get_mac_address(struct device *dev, void *addrbuf);
 32u32 eth_get_headlen(const struct net_device *dev, void *data, unsigned int len);
 33__be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev);
 34extern const struct header_ops eth_header_ops;
 35
 36int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type,
 37	       const void *daddr, const void *saddr, unsigned len);
 38int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr);
 39int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh,
 40		     __be16 type);
 41void eth_header_cache_update(struct hh_cache *hh, const struct net_device *dev,
 42			     const unsigned char *haddr);
 43__be16 eth_header_parse_protocol(const struct sk_buff *skb);
 44int eth_prepare_mac_addr_change(struct net_device *dev, void *p);
 45void eth_commit_mac_addr_change(struct net_device *dev, void *p);
 46int eth_mac_addr(struct net_device *dev, void *p);
 47int eth_validate_addr(struct net_device *dev);
 
 
 48
 49struct net_device *alloc_etherdev_mqs(int sizeof_priv, unsigned int txqs,
 50					    unsigned int rxqs);
 51#define alloc_etherdev(sizeof_priv) alloc_etherdev_mq(sizeof_priv, 1)
 52#define alloc_etherdev_mq(sizeof_priv, count) alloc_etherdev_mqs(sizeof_priv, count, count)
 53
 54struct net_device *devm_alloc_etherdev_mqs(struct device *dev, int sizeof_priv,
 55					   unsigned int txqs,
 56					   unsigned int rxqs);
 57#define devm_alloc_etherdev(dev, sizeof_priv) devm_alloc_etherdev_mqs(dev, sizeof_priv, 1, 1)
 58
 59struct sk_buff *eth_gro_receive(struct list_head *head, struct sk_buff *skb);
 60int eth_gro_complete(struct sk_buff *skb, int nhoff);
 61
 62/* Reserved Ethernet Addresses per IEEE 802.1Q */
 63static const u8 eth_reserved_addr_base[ETH_ALEN] __aligned(2) =
 64{ 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
 65#define eth_stp_addr eth_reserved_addr_base
 66
 67/**
 68 * is_link_local_ether_addr - Determine if given Ethernet address is link-local
 69 * @addr: Pointer to a six-byte array containing the Ethernet address
 70 *
 71 * Return true if address is link local reserved addr (01:80:c2:00:00:0X) per
 72 * IEEE 802.1Q 8.6.3 Frame filtering.
 73 *
 74 * Please note: addr must be aligned to u16.
 75 */
 76static inline bool is_link_local_ether_addr(const u8 *addr)
 77{
 78	__be16 *a = (__be16 *)addr;
 79	static const __be16 *b = (const __be16 *)eth_reserved_addr_base;
 80	static const __be16 m = cpu_to_be16(0xfff0);
 81
 82#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
 83	return (((*(const u32 *)addr) ^ (*(const u32 *)b)) |
 84		(__force int)((a[2] ^ b[2]) & m)) == 0;
 85#else
 86	return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | ((a[2] ^ b[2]) & m)) == 0;
 87#endif
 88}
 89
 90/**
 91 * is_zero_ether_addr - Determine if give Ethernet address is all zeros.
 92 * @addr: Pointer to a six-byte array containing the Ethernet address
 93 *
 94 * Return true if the address is all zeroes.
 95 *
 96 * Please note: addr must be aligned to u16.
 97 */
 98static inline bool is_zero_ether_addr(const u8 *addr)
 99{
100#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
101	return ((*(const u32 *)addr) | (*(const u16 *)(addr + 4))) == 0;
102#else
103	return (*(const u16 *)(addr + 0) |
104		*(const u16 *)(addr + 2) |
105		*(const u16 *)(addr + 4)) == 0;
106#endif
107}
108
109/**
110 * is_multicast_ether_addr - Determine if the Ethernet address is a multicast.
111 * @addr: Pointer to a six-byte array containing the Ethernet address
112 *
113 * Return true if the address is a multicast address.
114 * By definition the broadcast address is also a multicast address.
115 */
116static inline bool is_multicast_ether_addr(const u8 *addr)
117{
118#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
119	u32 a = *(const u32 *)addr;
120#else
121	u16 a = *(const u16 *)addr;
122#endif
123#ifdef __BIG_ENDIAN
124	return 0x01 & (a >> ((sizeof(a) * 8) - 8));
125#else
126	return 0x01 & a;
127#endif
128}
129
130static inline bool is_multicast_ether_addr_64bits(const u8 addr[6+2])
131{
132#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
133#ifdef __BIG_ENDIAN
134	return 0x01 & ((*(const u64 *)addr) >> 56);
135#else
136	return 0x01 & (*(const u64 *)addr);
137#endif
138#else
139	return is_multicast_ether_addr(addr);
140#endif
141}
142
143/**
144 * is_local_ether_addr - Determine if the Ethernet address is locally-assigned one (IEEE 802).
145 * @addr: Pointer to a six-byte array containing the Ethernet address
146 *
147 * Return true if the address is a local address.
148 */
149static inline bool is_local_ether_addr(const u8 *addr)
150{
151	return 0x02 & addr[0];
152}
153
154/**
155 * is_broadcast_ether_addr - Determine if the Ethernet address is broadcast
156 * @addr: Pointer to a six-byte array containing the Ethernet address
157 *
158 * Return true if the address is the broadcast address.
159 *
160 * Please note: addr must be aligned to u16.
161 */
162static inline bool is_broadcast_ether_addr(const u8 *addr)
163{
164	return (*(const u16 *)(addr + 0) &
165		*(const u16 *)(addr + 2) &
166		*(const u16 *)(addr + 4)) == 0xffff;
167}
168
169/**
170 * is_unicast_ether_addr - Determine if the Ethernet address is unicast
171 * @addr: Pointer to a six-byte array containing the Ethernet address
172 *
173 * Return true if the address is a unicast address.
174 */
175static inline bool is_unicast_ether_addr(const u8 *addr)
176{
177	return !is_multicast_ether_addr(addr);
178}
179
180/**
181 * is_valid_ether_addr - Determine if the given Ethernet address is valid
182 * @addr: Pointer to a six-byte array containing the Ethernet address
183 *
184 * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not
185 * a multicast address, and is not FF:FF:FF:FF:FF:FF.
186 *
187 * Return true if the address is valid.
188 *
189 * Please note: addr must be aligned to u16.
190 */
191static inline bool is_valid_ether_addr(const u8 *addr)
192{
193	/* FF:FF:FF:FF:FF:FF is a multicast address so we don't need to
194	 * explicitly check for it here. */
195	return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr);
196}
197
198/**
199 * eth_proto_is_802_3 - Determine if a given Ethertype/length is a protocol
200 * @proto: Ethertype/length value to be tested
201 *
202 * Check that the value from the Ethertype/length field is a valid Ethertype.
203 *
204 * Return true if the valid is an 802.3 supported Ethertype.
205 */
206static inline bool eth_proto_is_802_3(__be16 proto)
207{
208#ifndef __BIG_ENDIAN
209	/* if CPU is little endian mask off bits representing LSB */
210	proto &= htons(0xFF00);
211#endif
212	/* cast both to u16 and compare since LSB can be ignored */
213	return (__force u16)proto >= (__force u16)htons(ETH_P_802_3_MIN);
214}
215
216/**
217 * eth_random_addr - Generate software assigned random Ethernet address
218 * @addr: Pointer to a six-byte array containing the Ethernet address
219 *
220 * Generate a random Ethernet address (MAC) that is not multicast
221 * and has the local assigned bit set.
222 */
223static inline void eth_random_addr(u8 *addr)
224{
225	get_random_bytes(addr, ETH_ALEN);
226	addr[0] &= 0xfe;	/* clear multicast bit */
227	addr[0] |= 0x02;	/* set local assignment bit (IEEE802) */
228}
229
230#define random_ether_addr(addr) eth_random_addr(addr)
231
232/**
233 * eth_broadcast_addr - Assign broadcast address
234 * @addr: Pointer to a six-byte array containing the Ethernet address
235 *
236 * Assign the broadcast address to the given address array.
237 */
238static inline void eth_broadcast_addr(u8 *addr)
239{
240	memset(addr, 0xff, ETH_ALEN);
 
 
241}
242
243/**
244 * eth_zero_addr - Assign zero address
245 * @addr: Pointer to a six-byte array containing the Ethernet address
246 *
247 * Assign the zero address to the given address array.
248 */
249static inline void eth_zero_addr(u8 *addr)
250{
251	memset(addr, 0x00, ETH_ALEN);
252}
253
254/**
255 * eth_hw_addr_random - Generate software assigned random Ethernet and
256 * set device flag
257 * @dev: pointer to net_device structure
 
258 *
259 * Generate a random Ethernet address (MAC) to be used by a net device
260 * and set addr_assign_type so the state can be read by sysfs and be
261 * used by userspace.
262 */
263static inline void eth_hw_addr_random(struct net_device *dev)
264{
265	dev->addr_assign_type = NET_ADDR_RANDOM;
266	eth_random_addr(dev->dev_addr);
267}
268
269/**
270 * eth_hw_addr_crc - Calculate CRC from netdev_hw_addr
271 * @ha: pointer to hardware address
272 *
273 * Calculate CRC from a hardware address as basis for filter hashes.
274 */
275static inline u32 eth_hw_addr_crc(struct netdev_hw_addr *ha)
276{
277	return ether_crc(ETH_ALEN, ha->addr);
278}
279
280/**
281 * ether_addr_copy - Copy an Ethernet address
282 * @dst: Pointer to a six-byte array Ethernet address destination
283 * @src: Pointer to a six-byte array Ethernet address source
284 *
285 * Please note: dst & src must both be aligned to u16.
286 */
287static inline void ether_addr_copy(u8 *dst, const u8 *src)
288{
289#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
290	*(u32 *)dst = *(const u32 *)src;
291	*(u16 *)(dst + 4) = *(const u16 *)(src + 4);
292#else
293	u16 *a = (u16 *)dst;
294	const u16 *b = (const u16 *)src;
295
296	a[0] = b[0];
297	a[1] = b[1];
298	a[2] = b[2];
299#endif
300}
301
302/**
303 * eth_hw_addr_inherit - Copy dev_addr from another net_device
304 * @dst: pointer to net_device to copy dev_addr to
305 * @src: pointer to net_device to copy dev_addr from
306 *
307 * Copy the Ethernet address from one net_device to another along with
308 * the address attributes (addr_assign_type).
309 */
310static inline void eth_hw_addr_inherit(struct net_device *dst,
311				       struct net_device *src)
312{
313	dst->addr_assign_type = src->addr_assign_type;
314	ether_addr_copy(dst->dev_addr, src->dev_addr);
315}
316
317/**
318 * ether_addr_equal - Compare two Ethernet addresses
319 * @addr1: Pointer to a six-byte array containing the Ethernet address
320 * @addr2: Pointer other six-byte array containing the Ethernet address
321 *
322 * Compare two Ethernet addresses, returns true if equal
323 *
324 * Please note: addr1 & addr2 must both be aligned to u16.
325 */
326static inline bool ether_addr_equal(const u8 *addr1, const u8 *addr2)
327{
328#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
329	u32 fold = ((*(const u32 *)addr1) ^ (*(const u32 *)addr2)) |
330		   ((*(const u16 *)(addr1 + 4)) ^ (*(const u16 *)(addr2 + 4)));
331
332	return fold == 0;
333#else
334	const u16 *a = (const u16 *)addr1;
335	const u16 *b = (const u16 *)addr2;
336
337	return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) == 0;
338#endif
339}
340
341/**
342 * ether_addr_equal_64bits - Compare two Ethernet addresses
343 * @addr1: Pointer to an array of 8 bytes
344 * @addr2: Pointer to an other array of 8 bytes
345 *
346 * Compare two Ethernet addresses, returns true if equal, false otherwise.
347 *
348 * The function doesn't need any conditional branches and possibly uses
349 * word memory accesses on CPU allowing cheap unaligned memory reads.
350 * arrays = { byte1, byte2, byte3, byte4, byte5, byte6, pad1, pad2 }
351 *
352 * Please note that alignment of addr1 & addr2 are only guaranteed to be 16 bits.
353 */
354
355static inline bool ether_addr_equal_64bits(const u8 addr1[6+2],
356					   const u8 addr2[6+2])
357{
358#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
359	u64 fold = (*(const u64 *)addr1) ^ (*(const u64 *)addr2);
 
360
361#ifdef __BIG_ENDIAN
362	return (fold >> 16) == 0;
363#else
364	return (fold << 16) == 0;
365#endif
366#else
367	return ether_addr_equal(addr1, addr2);
368#endif
369}
370
371/**
372 * ether_addr_equal_unaligned - Compare two not u16 aligned Ethernet addresses
373 * @addr1: Pointer to a six-byte array containing the Ethernet address
374 * @addr2: Pointer other six-byte array containing the Ethernet address
375 *
376 * Compare two Ethernet addresses, returns true if equal
377 *
378 * Please note: Use only when any Ethernet address may not be u16 aligned.
379 */
380static inline bool ether_addr_equal_unaligned(const u8 *addr1, const u8 *addr2)
381{
382#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
383	return ether_addr_equal(addr1, addr2);
384#else
385	return memcmp(addr1, addr2, ETH_ALEN) == 0;
386#endif
387}
388
389/**
390 * ether_addr_equal_masked - Compare two Ethernet addresses with a mask
391 * @addr1: Pointer to a six-byte array containing the 1st Ethernet address
392 * @addr2: Pointer to a six-byte array containing the 2nd Ethernet address
393 * @mask: Pointer to a six-byte array containing the Ethernet address bitmask
394 *
395 * Compare two Ethernet addresses with a mask, returns true if for every bit
396 * set in the bitmask the equivalent bits in the ethernet addresses are equal.
397 * Using a mask with all bits set is a slower ether_addr_equal.
398 */
399static inline bool ether_addr_equal_masked(const u8 *addr1, const u8 *addr2,
400					   const u8 *mask)
401{
402	int i;
403
404	for (i = 0; i < ETH_ALEN; i++) {
405		if ((addr1[i] ^ addr2[i]) & mask[i])
406			return false;
407	}
408
409	return true;
410}
411
412/**
413 * ether_addr_to_u64 - Convert an Ethernet address into a u64 value.
414 * @addr: Pointer to a six-byte array containing the Ethernet address
415 *
416 * Return a u64 value of the address
417 */
418static inline u64 ether_addr_to_u64(const u8 *addr)
419{
420	u64 u = 0;
421	int i;
422
423	for (i = 0; i < ETH_ALEN; i++)
424		u = u << 8 | addr[i];
425
426	return u;
427}
428
429/**
430 * u64_to_ether_addr - Convert a u64 to an Ethernet address.
431 * @u: u64 to convert to an Ethernet MAC address
432 * @addr: Pointer to a six-byte array to contain the Ethernet address
433 */
434static inline void u64_to_ether_addr(u64 u, u8 *addr)
435{
436	int i;
437
438	for (i = ETH_ALEN - 1; i >= 0; i--) {
439		addr[i] = u & 0xff;
440		u = u >> 8;
441	}
442}
443
444/**
445 * eth_addr_dec - Decrement the given MAC address
446 *
447 * @addr: Pointer to a six-byte array containing Ethernet address to decrement
448 */
449static inline void eth_addr_dec(u8 *addr)
450{
451	u64 u = ether_addr_to_u64(addr);
452
453	u--;
454	u64_to_ether_addr(u, addr);
455}
456
457/**
458 * eth_addr_inc() - Increment the given MAC address.
459 * @addr: Pointer to a six-byte array containing Ethernet address to increment.
460 */
461static inline void eth_addr_inc(u8 *addr)
462{
463	u64 u = ether_addr_to_u64(addr);
464
465	u++;
466	u64_to_ether_addr(u, addr);
467}
468
469/**
470 * is_etherdev_addr - Tell if given Ethernet address belongs to the device.
471 * @dev: Pointer to a device structure
472 * @addr: Pointer to a six-byte array containing the Ethernet address
473 *
474 * Compare passed address with all addresses of the device. Return true if the
475 * address if one of the device addresses.
476 *
477 * Note that this function calls ether_addr_equal_64bits() so take care of
478 * the right padding.
479 */
480static inline bool is_etherdev_addr(const struct net_device *dev,
481				    const u8 addr[6 + 2])
482{
483	struct netdev_hw_addr *ha;
484	bool res = false;
485
486	rcu_read_lock();
487	for_each_dev_addr(dev, ha) {
488		res = ether_addr_equal_64bits(addr, ha->addr);
489		if (res)
490			break;
491	}
492	rcu_read_unlock();
493	return res;
494}
495#endif	/* __KERNEL__ */
496
497/**
498 * compare_ether_header - Compare two Ethernet headers
499 * @a: Pointer to Ethernet header
500 * @b: Pointer to Ethernet header
501 *
502 * Compare two Ethernet headers, returns 0 if equal.
503 * This assumes that the network header (i.e., IP header) is 4-byte
504 * aligned OR the platform can handle unaligned access.  This is the
505 * case for all packets coming into netif_receive_skb or similar
506 * entry points.
507 */
508
509static inline unsigned long compare_ether_header(const void *a, const void *b)
510{
511#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
512	unsigned long fold;
513
514	/*
515	 * We want to compare 14 bytes:
516	 *  [a0 ... a13] ^ [b0 ... b13]
517	 * Use two long XOR, ORed together, with an overlap of two bytes.
518	 *  [a0  a1  a2  a3  a4  a5  a6  a7 ] ^ [b0  b1  b2  b3  b4  b5  b6  b7 ] |
519	 *  [a6  a7  a8  a9  a10 a11 a12 a13] ^ [b6  b7  b8  b9  b10 b11 b12 b13]
520	 * This means the [a6 a7] ^ [b6 b7] part is done two times.
521	*/
522	fold = *(unsigned long *)a ^ *(unsigned long *)b;
523	fold |= *(unsigned long *)(a + 6) ^ *(unsigned long *)(b + 6);
524	return fold;
525#else
526	u32 *a32 = (u32 *)((u8 *)a + 2);
527	u32 *b32 = (u32 *)((u8 *)b + 2);
528
529	return (*(u16 *)a ^ *(u16 *)b) | (a32[0] ^ b32[0]) |
530	       (a32[1] ^ b32[1]) | (a32[2] ^ b32[2]);
531#endif
532}
533
534/**
535 * eth_skb_pad - Pad buffer to mininum number of octets for Ethernet frame
536 * @skb: Buffer to pad
537 *
538 * An Ethernet frame should have a minimum size of 60 bytes.  This function
539 * takes short frames and pads them with zeros up to the 60 byte limit.
540 */
541static inline int eth_skb_pad(struct sk_buff *skb)
542{
543	return skb_put_padto(skb, ETH_ZLEN);
544}
545
546#endif	/* _LINUX_ETHERDEVICE_H */
v3.1
 
  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#include <asm/unaligned.h>
 
 31
 32#ifdef __KERNEL__
 33extern __be16		eth_type_trans(struct sk_buff *skb, struct net_device *dev);
 
 
 
 
 
 34extern 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, __be16 type);
 42extern void eth_header_cache_update(struct hh_cache *hh,
 43				    const struct net_device *dev,
 44				    const unsigned char *haddr);
 45extern 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
 49
 50
 51extern struct net_device *alloc_etherdev_mqs(int sizeof_priv, unsigned int txqs,
 52					    unsigned int rxqs);
 53#define alloc_etherdev(sizeof_priv) alloc_etherdev_mq(sizeof_priv, 1)
 54#define alloc_etherdev_mq(sizeof_priv, count) alloc_etherdev_mqs(sizeof_priv, count, count)
 55
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 56/**
 57 * is_zero_ether_addr - Determine if give Ethernet address is all zeros.
 58 * @addr: Pointer to a six-byte array containing the Ethernet address
 59 *
 60 * Return true if the address is all zeroes.
 
 
 61 */
 62static inline int is_zero_ether_addr(const u8 *addr)
 63{
 64	return !(addr[0] | addr[1] | addr[2] | addr[3] | addr[4] | addr[5]);
 
 
 
 
 
 
 65}
 66
 67/**
 68 * is_multicast_ether_addr - Determine if the Ethernet address is a multicast.
 69 * @addr: Pointer to a six-byte array containing the Ethernet address
 70 *
 71 * Return true if the address is a multicast address.
 72 * By definition the broadcast address is also a multicast address.
 73 */
 74static inline int is_multicast_ether_addr(const u8 *addr)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 75{
 76	return 0x01 & addr[0];
 
 
 
 
 
 
 
 
 77}
 78
 79/**
 80 * is_local_ether_addr - Determine if the Ethernet address is locally-assigned one (IEEE 802).
 81 * @addr: Pointer to a six-byte array containing the Ethernet address
 82 *
 83 * Return true if the address is a local address.
 84 */
 85static inline int is_local_ether_addr(const u8 *addr)
 86{
 87	return 0x02 & addr[0];
 88}
 89
 90/**
 91 * is_broadcast_ether_addr - Determine if the Ethernet address is broadcast
 92 * @addr: Pointer to a six-byte array containing the Ethernet address
 93 *
 94 * Return true if the address is the broadcast address.
 
 
 95 */
 96static inline int is_broadcast_ether_addr(const u8 *addr)
 97{
 98	return (addr[0] & addr[1] & addr[2] & addr[3] & addr[4] & addr[5]) == 0xff;
 
 
 99}
100
101/**
102 * is_unicast_ether_addr - Determine if the Ethernet address is unicast
103 * @addr: Pointer to a six-byte array containing the Ethernet address
104 *
105 * Return true if the address is a unicast address.
106 */
107static inline int is_unicast_ether_addr(const u8 *addr)
108{
109	return !is_multicast_ether_addr(addr);
110}
111
112/**
113 * is_valid_ether_addr - Determine if the given Ethernet address is valid
114 * @addr: Pointer to a six-byte array containing the Ethernet address
115 *
116 * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not
117 * a multicast address, and is not FF:FF:FF:FF:FF:FF.
118 *
119 * Return true if the address is valid.
 
 
120 */
121static inline int is_valid_ether_addr(const u8 *addr)
122{
123	/* FF:FF:FF:FF:FF:FF is a multicast address so we don't need to
124	 * explicitly check for it here. */
125	return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr);
126}
127
128/**
129 * random_ether_addr - Generate software assigned random Ethernet address
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
130 * @addr: Pointer to a six-byte array containing the Ethernet address
131 *
132 * Generate a random Ethernet address (MAC) that is not multicast
133 * and has the local assigned bit set.
134 */
135static inline void random_ether_addr(u8 *addr)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
136{
137	get_random_bytes (addr, ETH_ALEN);
138	addr [0] &= 0xfe;	/* clear multicast bit */
139	addr [0] |= 0x02;	/* set local assignment bit (IEEE802) */
140}
141
142/**
143 * dev_hw_addr_random - Create random MAC and set device flag
 
 
 
 
 
 
 
 
 
 
 
 
144 * @dev: pointer to net_device structure
145 * @hwaddr: Pointer to a six-byte array containing the Ethernet address
146 *
147 * Generate random MAC to be used by a device and set addr_assign_type
148 * so the state can be read by sysfs and be used by udev.
 
149 */
150static inline void dev_hw_addr_random(struct net_device *dev, u8 *hwaddr)
151{
152	dev->addr_assign_type |= NET_ADDR_RANDOM;
153	random_ether_addr(hwaddr);
154}
155
156/**
157 * compare_ether_addr - Compare two Ethernet addresses
158 * @addr1: Pointer to a six-byte array containing the Ethernet address
159 * @addr2: Pointer other six-byte array containing the Ethernet address
 
 
 
 
 
 
 
 
 
 
 
160 *
161 * Compare two ethernet addresses, returns 0 if equal
162 */
163static inline unsigned compare_ether_addr(const u8 *addr1, const u8 *addr2)
164{
165	const u16 *a = (const u16 *) addr1;
166	const u16 *b = (const u16 *) addr2;
 
 
 
 
167
168	BUILD_BUG_ON(ETH_ALEN != 6);
169	return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) != 0;
 
 
170}
171
172static inline unsigned long zap_last_2bytes(unsigned long value)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
173{
174#ifdef __BIG_ENDIAN
175	return value >> 16;
 
 
 
176#else
177	return value << 16;
 
 
 
178#endif
179}
180
181/**
182 * compare_ether_addr_64bits - Compare two Ethernet addresses
183 * @addr1: Pointer to an array of 8 bytes
184 * @addr2: Pointer to an other array of 8 bytes
185 *
186 * Compare two ethernet addresses, returns 0 if equal.
187 * Same result than "memcmp(addr1, addr2, ETH_ALEN)" but without conditional
188 * branches, and possibly long word memory accesses on CPU allowing cheap
189 * unaligned memory reads.
190 * arrays = { byte1, byte2, byte3, byte4, byte6, byte7, pad1, pad2}
191 *
192 * Please note that alignment of addr1 & addr2 is only guaranted to be 16 bits.
193 */
194
195static inline unsigned compare_ether_addr_64bits(const u8 addr1[6+2],
196						 const u8 addr2[6+2])
197{
198#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
199	unsigned long fold = ((*(unsigned long *)addr1) ^
200			      (*(unsigned long *)addr2));
201
202	if (sizeof(fold) == 8)
203		return zap_last_2bytes(fold) != 0;
 
 
 
 
 
 
 
204
205	fold |= zap_last_2bytes((*(unsigned long *)(addr1 + 4)) ^
206				(*(unsigned long *)(addr2 + 4)));
207	return fold != 0;
 
 
 
 
 
 
 
 
 
 
208#else
209	return compare_ether_addr(addr1, addr2);
210#endif
211}
212
213/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
214 * is_etherdev_addr - Tell if given Ethernet address belongs to the device.
215 * @dev: Pointer to a device structure
216 * @addr: Pointer to a six-byte array containing the Ethernet address
217 *
218 * Compare passed address with all addresses of the device. Return true if the
219 * address if one of the device addresses.
220 *
221 * Note that this function calls compare_ether_addr_64bits() so take care of
222 * the right padding.
223 */
224static inline bool is_etherdev_addr(const struct net_device *dev,
225				    const u8 addr[6 + 2])
226{
227	struct netdev_hw_addr *ha;
228	int res = 1;
229
230	rcu_read_lock();
231	for_each_dev_addr(dev, ha) {
232		res = compare_ether_addr_64bits(addr, ha->addr);
233		if (!res)
234			break;
235	}
236	rcu_read_unlock();
237	return !res;
238}
239#endif	/* __KERNEL__ */
240
241/**
242 * compare_ether_header - Compare two Ethernet headers
243 * @a: Pointer to Ethernet header
244 * @b: Pointer to Ethernet header
245 *
246 * Compare two ethernet headers, returns 0 if equal.
247 * This assumes that the network header (i.e., IP header) is 4-byte
248 * aligned OR the platform can handle unaligned access.  This is the
249 * case for all packets coming into netif_receive_skb or similar
250 * entry points.
251 */
252
253static inline unsigned long compare_ether_header(const void *a, const void *b)
254{
255#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
256	unsigned long fold;
257
258	/*
259	 * We want to compare 14 bytes:
260	 *  [a0 ... a13] ^ [b0 ... b13]
261	 * Use two long XOR, ORed together, with an overlap of two bytes.
262	 *  [a0  a1  a2  a3  a4  a5  a6  a7 ] ^ [b0  b1  b2  b3  b4  b5  b6  b7 ] |
263	 *  [a6  a7  a8  a9  a10 a11 a12 a13] ^ [b6  b7  b8  b9  b10 b11 b12 b13]
264	 * This means the [a6 a7] ^ [b6 b7] part is done two times.
265	*/
266	fold = *(unsigned long *)a ^ *(unsigned long *)b;
267	fold |= *(unsigned long *)(a + 6) ^ *(unsigned long *)(b + 6);
268	return fold;
269#else
270	u32 *a32 = (u32 *)((u8 *)a + 2);
271	u32 *b32 = (u32 *)((u8 *)b + 2);
272
273	return (*(u16 *)a ^ *(u16 *)b) | (a32[0] ^ b32[0]) |
274	       (a32[1] ^ b32[1]) | (a32[2] ^ b32[2]);
275#endif
 
 
 
 
 
 
 
 
 
 
 
 
276}
277
278#endif	/* _LINUX_ETHERDEVICE_H */