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__
28 struct device;
29 int eth_platform_get_mac_address(struct device *dev, u8 *mac_addr);
30 unsigned char *arch_get_platform_mac_address(void);
31 int nvmem_get_mac_address(struct device *dev, void *addrbuf);
32 u32 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);
34 extern const struct header_ops eth_header_ops;
35
36 int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type,
37 const void *daddr, const void *saddr, unsigned len);
38 int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr);
39 int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh,
40 __be16 type);
41 void 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);
44 int eth_prepare_mac_addr_change(struct net_device *dev, void *p);
45 void eth_commit_mac_addr_change(struct net_device *dev, void *p);
46 int eth_mac_addr(struct net_device *dev, void *p);
47 int eth_validate_addr(struct net_device *dev);
48
49 struct 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
54 struct 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
59 struct sk_buff *eth_gro_receive(struct list_head *head, struct sk_buff *skb);
60 int eth_gro_complete(struct sk_buff *skb, int nhoff);
61
62 /* Reserved Ethernet Addresses per IEEE 802.1Q */
63 static 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 */
is_link_local_ether_addr(const u8 * addr)76 static 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 */
is_zero_ether_addr(const u8 * addr)98 static 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 */
is_multicast_ether_addr(const u8 * addr)116 static 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
is_multicast_ether_addr_64bits(const u8 addr[6+2])130 static 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 */
is_local_ether_addr(const u8 * addr)149 static 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 */
is_broadcast_ether_addr(const u8 * addr)162 static 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 */
is_unicast_ether_addr(const u8 * addr)175 static 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 */
is_valid_ether_addr(const u8 * addr)191 static 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 */
eth_proto_is_802_3(__be16 proto)206 static 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 */
eth_random_addr(u8 * addr)223 static 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 */
eth_broadcast_addr(u8 * addr)238 static 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 */
eth_zero_addr(u8 * addr)249 static 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 */
eth_hw_addr_random(struct net_device * dev)263 static 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 */
eth_hw_addr_crc(struct netdev_hw_addr * ha)275 static 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 */
ether_addr_copy(u8 * dst,const u8 * src)287 static 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 */
eth_hw_addr_inherit(struct net_device * dst,struct net_device * src)310 static 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 */
ether_addr_equal(const u8 * addr1,const u8 * addr2)326 static 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
ether_addr_equal_64bits(const u8 addr1[6+2],const u8 addr2[6+2])355 static 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 */
ether_addr_equal_unaligned(const u8 * addr1,const u8 * addr2)380 static 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 */
ether_addr_equal_masked(const u8 * addr1,const u8 * addr2,const u8 * mask)399 static 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 */
ether_addr_to_u64(const u8 * addr)418 static 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 */
u64_to_ether_addr(u64 u,u8 * addr)434 static 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 */
eth_addr_dec(u8 * addr)449 static 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 */
eth_addr_inc(u8 * addr)461 static 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 */
is_etherdev_addr(const struct net_device * dev,const u8 addr[6+2])480 static 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
compare_ether_header(const void * a,const void * b)509 static 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 */
eth_skb_pad(struct sk_buff * skb)541 static 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 */
547