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.
6 * Definitions for the Ethernet handlers.
8 * Version: @(#)eth.h 1.0.4 05/13/93
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
13 * Relocated to include/linux where it belongs by Alan Cox
14 * <gw4pts@gw4pts.ampr.org>
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.
22 #ifndef _LINUX_ETHERDEVICE_H
23 #define _LINUX_ETHERDEVICE_H
25 #include <linux/if_ether.h>
26 #include <linux/netdevice.h>
27 #include <linux/random.h>
28 #include <asm/unaligned.h>
29 #include <asm/bitsperlong.h>
32 u32 eth_get_headlen(void *data, unsigned int max_len);
33 __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev);
34 extern const struct header_ops eth_header_ops;
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_rebuild_header(struct sk_buff *skb);
39 int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr);
40 int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh,
42 void eth_header_cache_update(struct hh_cache *hh, const struct net_device *dev,
43 const unsigned char *haddr);
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_change_mtu(struct net_device *dev, int new_mtu);
48 int eth_validate_addr(struct net_device *dev);
50 struct net_device *alloc_etherdev_mqs(int sizeof_priv, unsigned int txqs,
52 #define alloc_etherdev(sizeof_priv) alloc_etherdev_mq(sizeof_priv, 1)
53 #define alloc_etherdev_mq(sizeof_priv, count) alloc_etherdev_mqs(sizeof_priv, count, count)
55 struct sk_buff **eth_gro_receive(struct sk_buff **head,
57 int eth_gro_complete(struct sk_buff *skb, int nhoff);
59 /* Reserved Ethernet Addresses per IEEE 802.1Q */
60 static const u8 eth_reserved_addr_base[ETH_ALEN] __aligned(2) =
61 { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
64 * is_link_local_ether_addr - Determine if given Ethernet address is link-local
65 * @addr: Pointer to a six-byte array containing the Ethernet address
67 * Return true if address is link local reserved addr (01:80:c2:00:00:0X) per
68 * IEEE 802.1Q 8.6.3 Frame filtering.
70 * Please note: addr must be aligned to u16.
72 static inline bool is_link_local_ether_addr(const u8 *addr)
74 __be16 *a = (__be16 *)addr;
75 static const __be16 *b = (const __be16 *)eth_reserved_addr_base;
76 static const __be16 m = cpu_to_be16(0xfff0);
78 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
79 return (((*(const u32 *)addr) ^ (*(const u32 *)b)) |
80 ((a[2] ^ b[2]) & m)) == 0;
82 return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | ((a[2] ^ b[2]) & m)) == 0;
87 * is_zero_ether_addr - Determine if give Ethernet address is all zeros.
88 * @addr: Pointer to a six-byte array containing the Ethernet address
90 * Return true if the address is all zeroes.
92 * Please note: addr must be aligned to u16.
94 static inline bool is_zero_ether_addr(const u8 *addr)
96 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
97 return ((*(const u32 *)addr) | (*(const u16 *)(addr + 4))) == 0;
99 return (*(const u16 *)(addr + 0) |
100 *(const u16 *)(addr + 2) |
101 *(const u16 *)(addr + 4)) == 0;
106 * is_multicast_ether_addr - Determine if the Ethernet address is a multicast.
107 * @addr: Pointer to a six-byte array containing the Ethernet address
109 * Return true if the address is a multicast address.
110 * By definition the broadcast address is also a multicast address.
112 static inline bool is_multicast_ether_addr(const u8 *addr)
114 return 0x01 & addr[0];
118 * is_local_ether_addr - Determine if the Ethernet address is locally-assigned one (IEEE 802).
119 * @addr: Pointer to a six-byte array containing the Ethernet address
121 * Return true if the address is a local address.
123 static inline bool is_local_ether_addr(const u8 *addr)
125 return 0x02 & addr[0];
129 * is_broadcast_ether_addr - Determine if the Ethernet address is broadcast
130 * @addr: Pointer to a six-byte array containing the Ethernet address
132 * Return true if the address is the broadcast address.
134 * Please note: addr must be aligned to u16.
136 static inline bool is_broadcast_ether_addr(const u8 *addr)
138 return (*(const u16 *)(addr + 0) &
139 *(const u16 *)(addr + 2) &
140 *(const u16 *)(addr + 4)) == 0xffff;
144 * is_unicast_ether_addr - Determine if the Ethernet address is unicast
145 * @addr: Pointer to a six-byte array containing the Ethernet address
147 * Return true if the address is a unicast address.
149 static inline bool is_unicast_ether_addr(const u8 *addr)
151 return !is_multicast_ether_addr(addr);
155 * is_valid_ether_addr - Determine if the given Ethernet address is valid
156 * @addr: Pointer to a six-byte array containing the Ethernet address
158 * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not
159 * a multicast address, and is not FF:FF:FF:FF:FF:FF.
161 * Return true if the address is valid.
163 * Please note: addr must be aligned to u16.
165 static inline bool is_valid_ether_addr(const u8 *addr)
167 /* FF:FF:FF:FF:FF:FF is a multicast address so we don't need to
168 * explicitly check for it here. */
169 return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr);
173 * eth_random_addr - Generate software assigned random Ethernet address
174 * @addr: Pointer to a six-byte array containing the Ethernet address
176 * Generate a random Ethernet address (MAC) that is not multicast
177 * and has the local assigned bit set.
179 static inline void eth_random_addr(u8 *addr)
181 get_random_bytes(addr, ETH_ALEN);
182 addr[0] &= 0xfe; /* clear multicast bit */
183 addr[0] |= 0x02; /* set local assignment bit (IEEE802) */
186 #define random_ether_addr(addr) eth_random_addr(addr)
189 * eth_broadcast_addr - Assign broadcast address
190 * @addr: Pointer to a six-byte array containing the Ethernet address
192 * Assign the broadcast address to the given address array.
194 static inline void eth_broadcast_addr(u8 *addr)
196 memset(addr, 0xff, ETH_ALEN);
200 * eth_zero_addr - Assign zero address
201 * @addr: Pointer to a six-byte array containing the Ethernet address
203 * Assign the zero address to the given address array.
205 static inline void eth_zero_addr(u8 *addr)
207 memset(addr, 0x00, ETH_ALEN);
211 * eth_hw_addr_random - Generate software assigned random Ethernet and
213 * @dev: pointer to net_device structure
215 * Generate a random Ethernet address (MAC) to be used by a net device
216 * and set addr_assign_type so the state can be read by sysfs and be
219 static inline void eth_hw_addr_random(struct net_device *dev)
221 dev->addr_assign_type = NET_ADDR_RANDOM;
222 eth_random_addr(dev->dev_addr);
226 * ether_addr_copy - Copy an Ethernet address
227 * @dst: Pointer to a six-byte array Ethernet address destination
228 * @src: Pointer to a six-byte array Ethernet address source
230 * Please note: dst & src must both be aligned to u16.
232 static inline void ether_addr_copy(u8 *dst, const u8 *src)
234 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
235 *(u32 *)dst = *(const u32 *)src;
236 *(u16 *)(dst + 4) = *(const u16 *)(src + 4);
239 const u16 *b = (const u16 *)src;
248 * eth_hw_addr_inherit - Copy dev_addr from another net_device
249 * @dst: pointer to net_device to copy dev_addr to
250 * @src: pointer to net_device to copy dev_addr from
252 * Copy the Ethernet address from one net_device to another along with
253 * the address attributes (addr_assign_type).
255 static inline void eth_hw_addr_inherit(struct net_device *dst,
256 struct net_device *src)
258 dst->addr_assign_type = src->addr_assign_type;
259 ether_addr_copy(dst->dev_addr, src->dev_addr);
263 * ether_addr_equal - Compare two Ethernet addresses
264 * @addr1: Pointer to a six-byte array containing the Ethernet address
265 * @addr2: Pointer other six-byte array containing the Ethernet address
267 * Compare two Ethernet addresses, returns true if equal
269 * Please note: addr1 & addr2 must both be aligned to u16.
271 static inline bool ether_addr_equal(const u8 *addr1, const u8 *addr2)
273 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
274 u32 fold = ((*(const u32 *)addr1) ^ (*(const u32 *)addr2)) |
275 ((*(const u16 *)(addr1 + 4)) ^ (*(const u16 *)(addr2 + 4)));
279 const u16 *a = (const u16 *)addr1;
280 const u16 *b = (const u16 *)addr2;
282 return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) == 0;
287 * ether_addr_equal_64bits - Compare two Ethernet addresses
288 * @addr1: Pointer to an array of 8 bytes
289 * @addr2: Pointer to an other array of 8 bytes
291 * Compare two Ethernet addresses, returns true if equal, false otherwise.
293 * The function doesn't need any conditional branches and possibly uses
294 * word memory accesses on CPU allowing cheap unaligned memory reads.
295 * arrays = { byte1, byte2, byte3, byte4, byte5, byte6, pad1, pad2 }
297 * Please note that alignment of addr1 & addr2 are only guaranteed to be 16 bits.
300 static inline bool ether_addr_equal_64bits(const u8 addr1[6+2],
303 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
304 u64 fold = (*(const u64 *)addr1) ^ (*(const u64 *)addr2);
307 return (fold >> 16) == 0;
309 return (fold << 16) == 0;
312 return ether_addr_equal(addr1, addr2);
317 * ether_addr_equal_unaligned - Compare two not u16 aligned Ethernet addresses
318 * @addr1: Pointer to a six-byte array containing the Ethernet address
319 * @addr2: Pointer other six-byte array containing the Ethernet address
321 * Compare two Ethernet addresses, returns true if equal
323 * Please note: Use only when any Ethernet address may not be u16 aligned.
325 static inline bool ether_addr_equal_unaligned(const u8 *addr1, const u8 *addr2)
327 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
328 return ether_addr_equal(addr1, addr2);
330 return memcmp(addr1, addr2, ETH_ALEN) == 0;
335 * is_etherdev_addr - Tell if given Ethernet address belongs to the device.
336 * @dev: Pointer to a device structure
337 * @addr: Pointer to a six-byte array containing the Ethernet address
339 * Compare passed address with all addresses of the device. Return true if the
340 * address if one of the device addresses.
342 * Note that this function calls ether_addr_equal_64bits() so take care of
345 static inline bool is_etherdev_addr(const struct net_device *dev,
346 const u8 addr[6 + 2])
348 struct netdev_hw_addr *ha;
352 for_each_dev_addr(dev, ha) {
353 res = ether_addr_equal_64bits(addr, ha->addr);
360 #endif /* __KERNEL__ */
363 * compare_ether_header - Compare two Ethernet headers
364 * @a: Pointer to Ethernet header
365 * @b: Pointer to Ethernet header
367 * Compare two Ethernet headers, returns 0 if equal.
368 * This assumes that the network header (i.e., IP header) is 4-byte
369 * aligned OR the platform can handle unaligned access. This is the
370 * case for all packets coming into netif_receive_skb or similar
374 static inline unsigned long compare_ether_header(const void *a, const void *b)
376 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
380 * We want to compare 14 bytes:
381 * [a0 ... a13] ^ [b0 ... b13]
382 * Use two long XOR, ORed together, with an overlap of two bytes.
383 * [a0 a1 a2 a3 a4 a5 a6 a7 ] ^ [b0 b1 b2 b3 b4 b5 b6 b7 ] |
384 * [a6 a7 a8 a9 a10 a11 a12 a13] ^ [b6 b7 b8 b9 b10 b11 b12 b13]
385 * This means the [a6 a7] ^ [b6 b7] part is done two times.
387 fold = *(unsigned long *)a ^ *(unsigned long *)b;
388 fold |= *(unsigned long *)(a + 6) ^ *(unsigned long *)(b + 6);
391 u32 *a32 = (u32 *)((u8 *)a + 2);
392 u32 *b32 = (u32 *)((u8 *)b + 2);
394 return (*(u16 *)a ^ *(u16 *)b) | (a32[0] ^ b32[0]) |
395 (a32[1] ^ b32[1]) | (a32[2] ^ b32[2]);
400 * eth_skb_pad - Pad buffer to mininum number of octets for Ethernet frame
401 * @skb: Buffer to pad
403 * An Ethernet frame should have a minimum size of 60 bytes. This function
404 * takes short frames and pads them with zeros up to the 60 byte limit.
406 static inline int eth_skb_pad(struct sk_buff *skb)
408 return skb_put_padto(skb, ETH_ZLEN);
411 #endif /* _LINUX_ETHERDEVICE_H */