etherdevice.h 12 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395
  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. */
  22. #ifndef _LINUX_ETHERDEVICE_H
  23. #define _LINUX_ETHERDEVICE_H
  24. #include <linux/if_ether.h>
  25. #include <linux/netdevice.h>
  26. #include <linux/random.h>
  27. #include <asm/unaligned.h>
  28. #include <asm/bitsperlong.h>
  29. #ifdef __KERNEL__
  30. u32 eth_get_headlen(void *data, unsigned int max_len);
  31. __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev);
  32. extern const struct header_ops eth_header_ops;
  33. int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type,
  34. const void *daddr, const void *saddr, unsigned len);
  35. int eth_rebuild_header(struct sk_buff *skb);
  36. int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr);
  37. int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh,
  38. __be16 type);
  39. void eth_header_cache_update(struct hh_cache *hh, const struct net_device *dev,
  40. const unsigned char *haddr);
  41. int eth_prepare_mac_addr_change(struct net_device *dev, void *p);
  42. void eth_commit_mac_addr_change(struct net_device *dev, void *p);
  43. int eth_mac_addr(struct net_device *dev, void *p);
  44. int eth_change_mtu(struct net_device *dev, int new_mtu);
  45. int eth_validate_addr(struct net_device *dev);
  46. struct net_device *alloc_etherdev_mqs(int sizeof_priv, unsigned int txqs,
  47. unsigned int rxqs);
  48. #define alloc_etherdev(sizeof_priv) alloc_etherdev_mq(sizeof_priv, 1)
  49. #define alloc_etherdev_mq(sizeof_priv, count) alloc_etherdev_mqs(sizeof_priv, count, count)
  50. /* Reserved Ethernet Addresses per IEEE 802.1Q */
  51. static const u8 eth_reserved_addr_base[ETH_ALEN] __aligned(2) =
  52. { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
  53. /**
  54. * is_link_local_ether_addr - Determine if given Ethernet address is link-local
  55. * @addr: Pointer to a six-byte array containing the Ethernet address
  56. *
  57. * Return true if address is link local reserved addr (01:80:c2:00:00:0X) per
  58. * IEEE 802.1Q 8.6.3 Frame filtering.
  59. *
  60. * Please note: addr must be aligned to u16.
  61. */
  62. static inline bool is_link_local_ether_addr(const u8 *addr)
  63. {
  64. __be16 *a = (__be16 *)addr;
  65. static const __be16 *b = (const __be16 *)eth_reserved_addr_base;
  66. static const __be16 m = cpu_to_be16(0xfff0);
  67. #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
  68. return (((*(const u32 *)addr) ^ (*(const u32 *)b)) |
  69. ((a[2] ^ b[2]) & m)) == 0;
  70. #else
  71. return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | ((a[2] ^ b[2]) & m)) == 0;
  72. #endif
  73. }
  74. /**
  75. * is_zero_ether_addr - Determine if give Ethernet address is all zeros.
  76. * @addr: Pointer to a six-byte array containing the Ethernet address
  77. *
  78. * Return true if the address is all zeroes.
  79. *
  80. * Please note: addr must be aligned to u16.
  81. */
  82. static inline bool is_zero_ether_addr(const u8 *addr)
  83. {
  84. #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
  85. return ((*(const u32 *)addr) | (*(const u16 *)(addr + 4))) == 0;
  86. #else
  87. return (*(const u16 *)(addr + 0) |
  88. *(const u16 *)(addr + 2) |
  89. *(const u16 *)(addr + 4)) == 0;
  90. #endif
  91. }
  92. /**
  93. * is_multicast_ether_addr - Determine if the Ethernet address is a multicast.
  94. * @addr: Pointer to a six-byte array containing the Ethernet address
  95. *
  96. * Return true if the address is a multicast address.
  97. * By definition the broadcast address is also a multicast address.
  98. */
  99. static inline bool is_multicast_ether_addr(const u8 *addr)
  100. {
  101. return 0x01 & addr[0];
  102. }
  103. /**
  104. * is_local_ether_addr - Determine if the Ethernet address is locally-assigned one (IEEE 802).
  105. * @addr: Pointer to a six-byte array containing the Ethernet address
  106. *
  107. * Return true if the address is a local address.
  108. */
  109. static inline bool is_local_ether_addr(const u8 *addr)
  110. {
  111. return 0x02 & addr[0];
  112. }
  113. /**
  114. * is_broadcast_ether_addr - Determine if the Ethernet address is broadcast
  115. * @addr: Pointer to a six-byte array containing the Ethernet address
  116. *
  117. * Return true if the address is the broadcast address.
  118. *
  119. * Please note: addr must be aligned to u16.
  120. */
  121. static inline bool is_broadcast_ether_addr(const u8 *addr)
  122. {
  123. return (*(const u16 *)(addr + 0) &
  124. *(const u16 *)(addr + 2) &
  125. *(const u16 *)(addr + 4)) == 0xffff;
  126. }
  127. /**
  128. * is_unicast_ether_addr - Determine if the Ethernet address is unicast
  129. * @addr: Pointer to a six-byte array containing the Ethernet address
  130. *
  131. * Return true if the address is a unicast address.
  132. */
  133. static inline bool is_unicast_ether_addr(const u8 *addr)
  134. {
  135. return !is_multicast_ether_addr(addr);
  136. }
  137. /**
  138. * is_valid_ether_addr - Determine if the given Ethernet address is valid
  139. * @addr: Pointer to a six-byte array containing the Ethernet address
  140. *
  141. * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not
  142. * a multicast address, and is not FF:FF:FF:FF:FF:FF.
  143. *
  144. * Return true if the address is valid.
  145. *
  146. * Please note: addr must be aligned to u16.
  147. */
  148. static inline bool is_valid_ether_addr(const u8 *addr)
  149. {
  150. /* FF:FF:FF:FF:FF:FF is a multicast address so we don't need to
  151. * explicitly check for it here. */
  152. return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr);
  153. }
  154. /**
  155. * eth_random_addr - Generate software assigned random Ethernet address
  156. * @addr: Pointer to a six-byte array containing the Ethernet address
  157. *
  158. * Generate a random Ethernet address (MAC) that is not multicast
  159. * and has the local assigned bit set.
  160. */
  161. static inline void eth_random_addr(u8 *addr)
  162. {
  163. get_random_bytes(addr, ETH_ALEN);
  164. addr[0] &= 0xfe; /* clear multicast bit */
  165. addr[0] |= 0x02; /* set local assignment bit (IEEE802) */
  166. }
  167. #define random_ether_addr(addr) eth_random_addr(addr)
  168. /**
  169. * eth_broadcast_addr - Assign broadcast address
  170. * @addr: Pointer to a six-byte array containing the Ethernet address
  171. *
  172. * Assign the broadcast address to the given address array.
  173. */
  174. static inline void eth_broadcast_addr(u8 *addr)
  175. {
  176. memset(addr, 0xff, ETH_ALEN);
  177. }
  178. /**
  179. * eth_zero_addr - Assign zero address
  180. * @addr: Pointer to a six-byte array containing the Ethernet address
  181. *
  182. * Assign the zero address to the given address array.
  183. */
  184. static inline void eth_zero_addr(u8 *addr)
  185. {
  186. memset(addr, 0x00, ETH_ALEN);
  187. }
  188. /**
  189. * eth_hw_addr_random - Generate software assigned random Ethernet and
  190. * set device flag
  191. * @dev: pointer to net_device structure
  192. *
  193. * Generate a random Ethernet address (MAC) to be used by a net device
  194. * and set addr_assign_type so the state can be read by sysfs and be
  195. * used by userspace.
  196. */
  197. static inline void eth_hw_addr_random(struct net_device *dev)
  198. {
  199. dev->addr_assign_type = NET_ADDR_RANDOM;
  200. eth_random_addr(dev->dev_addr);
  201. }
  202. /**
  203. * ether_addr_copy - Copy an Ethernet address
  204. * @dst: Pointer to a six-byte array Ethernet address destination
  205. * @src: Pointer to a six-byte array Ethernet address source
  206. *
  207. * Please note: dst & src must both be aligned to u16.
  208. */
  209. static inline void ether_addr_copy(u8 *dst, const u8 *src)
  210. {
  211. #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
  212. *(u32 *)dst = *(const u32 *)src;
  213. *(u16 *)(dst + 4) = *(const u16 *)(src + 4);
  214. #else
  215. u16 *a = (u16 *)dst;
  216. const u16 *b = (const u16 *)src;
  217. a[0] = b[0];
  218. a[1] = b[1];
  219. a[2] = b[2];
  220. #endif
  221. }
  222. /**
  223. * eth_hw_addr_inherit - Copy dev_addr from another net_device
  224. * @dst: pointer to net_device to copy dev_addr to
  225. * @src: pointer to net_device to copy dev_addr from
  226. *
  227. * Copy the Ethernet address from one net_device to another along with
  228. * the address attributes (addr_assign_type).
  229. */
  230. static inline void eth_hw_addr_inherit(struct net_device *dst,
  231. struct net_device *src)
  232. {
  233. dst->addr_assign_type = src->addr_assign_type;
  234. ether_addr_copy(dst->dev_addr, src->dev_addr);
  235. }
  236. /**
  237. * ether_addr_equal - Compare two Ethernet addresses
  238. * @addr1: Pointer to a six-byte array containing the Ethernet address
  239. * @addr2: Pointer other six-byte array containing the Ethernet address
  240. *
  241. * Compare two Ethernet addresses, returns true if equal
  242. *
  243. * Please note: addr1 & addr2 must both be aligned to u16.
  244. */
  245. static inline bool ether_addr_equal(const u8 *addr1, const u8 *addr2)
  246. {
  247. #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
  248. u32 fold = ((*(const u32 *)addr1) ^ (*(const u32 *)addr2)) |
  249. ((*(const u16 *)(addr1 + 4)) ^ (*(const u16 *)(addr2 + 4)));
  250. return fold == 0;
  251. #else
  252. const u16 *a = (const u16 *)addr1;
  253. const u16 *b = (const u16 *)addr2;
  254. return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) == 0;
  255. #endif
  256. }
  257. /**
  258. * ether_addr_equal_64bits - Compare two Ethernet addresses
  259. * @addr1: Pointer to an array of 8 bytes
  260. * @addr2: Pointer to an other array of 8 bytes
  261. *
  262. * Compare two Ethernet addresses, returns true if equal, false otherwise.
  263. *
  264. * The function doesn't need any conditional branches and possibly uses
  265. * word memory accesses on CPU allowing cheap unaligned memory reads.
  266. * arrays = { byte1, byte2, byte3, byte4, byte5, byte6, pad1, pad2 }
  267. *
  268. * Please note that alignment of addr1 & addr2 are only guaranteed to be 16 bits.
  269. */
  270. static inline bool ether_addr_equal_64bits(const u8 addr1[6+2],
  271. const u8 addr2[6+2])
  272. {
  273. #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
  274. u64 fold = (*(const u64 *)addr1) ^ (*(const u64 *)addr2);
  275. #ifdef __BIG_ENDIAN
  276. return (fold >> 16) == 0;
  277. #else
  278. return (fold << 16) == 0;
  279. #endif
  280. #else
  281. return ether_addr_equal(addr1, addr2);
  282. #endif
  283. }
  284. /**
  285. * ether_addr_equal_unaligned - Compare two not u16 aligned Ethernet addresses
  286. * @addr1: Pointer to a six-byte array containing the Ethernet address
  287. * @addr2: Pointer other six-byte array containing the Ethernet address
  288. *
  289. * Compare two Ethernet addresses, returns true if equal
  290. *
  291. * Please note: Use only when any Ethernet address may not be u16 aligned.
  292. */
  293. static inline bool ether_addr_equal_unaligned(const u8 *addr1, const u8 *addr2)
  294. {
  295. #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
  296. return ether_addr_equal(addr1, addr2);
  297. #else
  298. return memcmp(addr1, addr2, ETH_ALEN) == 0;
  299. #endif
  300. }
  301. /**
  302. * is_etherdev_addr - Tell if given Ethernet address belongs to the device.
  303. * @dev: Pointer to a device structure
  304. * @addr: Pointer to a six-byte array containing the Ethernet address
  305. *
  306. * Compare passed address with all addresses of the device. Return true if the
  307. * address if one of the device addresses.
  308. *
  309. * Note that this function calls ether_addr_equal_64bits() so take care of
  310. * the right padding.
  311. */
  312. static inline bool is_etherdev_addr(const struct net_device *dev,
  313. const u8 addr[6 + 2])
  314. {
  315. struct netdev_hw_addr *ha;
  316. bool res = false;
  317. rcu_read_lock();
  318. for_each_dev_addr(dev, ha) {
  319. res = ether_addr_equal_64bits(addr, ha->addr);
  320. if (res)
  321. break;
  322. }
  323. rcu_read_unlock();
  324. return res;
  325. }
  326. #endif /* __KERNEL__ */
  327. /**
  328. * compare_ether_header - Compare two Ethernet headers
  329. * @a: Pointer to Ethernet header
  330. * @b: Pointer to Ethernet header
  331. *
  332. * Compare two Ethernet headers, returns 0 if equal.
  333. * This assumes that the network header (i.e., IP header) is 4-byte
  334. * aligned OR the platform can handle unaligned access. This is the
  335. * case for all packets coming into netif_receive_skb or similar
  336. * entry points.
  337. */
  338. static inline unsigned long compare_ether_header(const void *a, const void *b)
  339. {
  340. #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
  341. unsigned long fold;
  342. /*
  343. * We want to compare 14 bytes:
  344. * [a0 ... a13] ^ [b0 ... b13]
  345. * Use two long XOR, ORed together, with an overlap of two bytes.
  346. * [a0 a1 a2 a3 a4 a5 a6 a7 ] ^ [b0 b1 b2 b3 b4 b5 b6 b7 ] |
  347. * [a6 a7 a8 a9 a10 a11 a12 a13] ^ [b6 b7 b8 b9 b10 b11 b12 b13]
  348. * This means the [a6 a7] ^ [b6 b7] part is done two times.
  349. */
  350. fold = *(unsigned long *)a ^ *(unsigned long *)b;
  351. fold |= *(unsigned long *)(a + 6) ^ *(unsigned long *)(b + 6);
  352. return fold;
  353. #else
  354. u32 *a32 = (u32 *)((u8 *)a + 2);
  355. u32 *b32 = (u32 *)((u8 *)b + 2);
  356. return (*(u16 *)a ^ *(u16 *)b) | (a32[0] ^ b32[0]) |
  357. (a32[1] ^ b32[1]) | (a32[2] ^ b32[2]);
  358. #endif
  359. }
  360. #endif /* _LINUX_ETHERDEVICE_H */