etherdevice.h 4.2 KB

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  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. #include <linux/if_ether.h>
  27. #include <linux/netdevice.h>
  28. #include <linux/random.h>
  29. #ifdef __KERNEL__
  30. extern int eth_header(struct sk_buff *skb, struct net_device *dev,
  31. unsigned short type, void *daddr,
  32. void *saddr, unsigned len);
  33. extern int eth_rebuild_header(struct sk_buff *skb);
  34. extern __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev);
  35. extern void eth_header_cache_update(struct hh_cache *hh, struct net_device *dev,
  36. unsigned char * haddr);
  37. extern int eth_header_cache(struct neighbour *neigh,
  38. struct hh_cache *hh);
  39. extern struct net_device *alloc_etherdev(int sizeof_priv);
  40. static inline void eth_copy_and_sum (struct sk_buff *dest,
  41. const unsigned char *src,
  42. int len, int base)
  43. {
  44. memcpy (dest->data, src, len);
  45. }
  46. /**
  47. * is_zero_ether_addr - Determine if give Ethernet address is all zeros.
  48. * @addr: Pointer to a six-byte array containing the Ethernet address
  49. *
  50. * Return true if the address is all zeroes.
  51. */
  52. static inline int is_zero_ether_addr(const u8 *addr)
  53. {
  54. return !(addr[0] | addr[1] | addr[2] | addr[3] | addr[4] | addr[5]);
  55. }
  56. /**
  57. * is_multicast_ether_addr - Determine if the Ethernet address is a multicast.
  58. * @addr: Pointer to a six-byte array containing the Ethernet address
  59. *
  60. * Return true if the address is a multicast address.
  61. * By definition the broadcast address is also a multicast address.
  62. */
  63. static inline int is_multicast_ether_addr(const u8 *addr)
  64. {
  65. return (0x01 & addr[0]);
  66. }
  67. /**
  68. * is_broadcast_ether_addr - Determine if the Ethernet address is broadcast
  69. * @addr: Pointer to a six-byte array containing the Ethernet address
  70. *
  71. * Return true if the address is the broadcast address.
  72. */
  73. static inline int is_broadcast_ether_addr(const u8 *addr)
  74. {
  75. return (addr[0] & addr[1] & addr[2] & addr[3] & addr[4] & addr[5]) == 0xff;
  76. }
  77. /**
  78. * is_valid_ether_addr - Determine if the given Ethernet address is valid
  79. * @addr: Pointer to a six-byte array containing the Ethernet address
  80. *
  81. * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not
  82. * a multicast address, and is not FF:FF:FF:FF:FF:FF.
  83. *
  84. * Return true if the address is valid.
  85. */
  86. static inline int is_valid_ether_addr(const u8 *addr)
  87. {
  88. /* FF:FF:FF:FF:FF:FF is a multicast address so we don't need to
  89. * explicitly check for it here. */
  90. return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr);
  91. }
  92. /**
  93. * random_ether_addr - Generate software assigned random Ethernet address
  94. * @addr: Pointer to a six-byte array containing the Ethernet address
  95. *
  96. * Generate a random Ethernet address (MAC) that is not multicast
  97. * and has the local assigned bit set.
  98. */
  99. static inline void random_ether_addr(u8 *addr)
  100. {
  101. get_random_bytes (addr, ETH_ALEN);
  102. addr [0] &= 0xfe; /* clear multicast bit */
  103. addr [0] |= 0x02; /* set local assignment bit (IEEE802) */
  104. }
  105. /**
  106. * compare_ether_addr - Compare two Ethernet addresses
  107. * @addr1: Pointer to a six-byte array containing the Ethernet address
  108. * @addr2: Pointer other six-byte array containing the Ethernet address
  109. *
  110. * Compare two ethernet addresses, returns 0 if equal
  111. */
  112. static inline unsigned compare_ether_addr(const u8 *addr1, const u8 *addr2)
  113. {
  114. const u16 *a = (const u16 *) addr1;
  115. const u16 *b = (const u16 *) addr2;
  116. BUILD_BUG_ON(ETH_ALEN != 6);
  117. return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) != 0;
  118. }
  119. #endif /* __KERNEL__ */
  120. #endif /* _LINUX_ETHERDEVICE_H */