LXR linux/include/linux/etherdevice.h

   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
  31#ifdef __KERNEL__
  32extern __be16           eth_type_trans(struct sk_buff *skb, struct net_device *dev);
  33extern const struct header_ops eth_header_ops;
  34
  35extern int eth_header(struct sk_buff *skb, struct net_device *dev,
  36                      unsigned short type,
  37                      const void *daddr, const void *saddr, unsigned len);
  38extern int eth_rebuild_header(struct sk_buff *skb);
  39extern int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr);
  40extern int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh);
  41extern void eth_header_cache_update(struct hh_cache *hh,
  42                                    const struct net_device *dev,
  43                                    const unsigned char *haddr);
  44
  45
  46extern struct net_device *alloc_etherdev_mq(int sizeof_priv, unsigned int queue_count);
  47#define alloc_etherdev(sizeof_priv) alloc_etherdev_mq(sizeof_priv, 1)
  48
  49/**
  50 * is_zero_ether_addr - Determine if give Ethernet address is all zeros.
  51 * @addr: Pointer to a six-byte array containing the Ethernet address
  52 *
  53 * Return true if the address is all zeroes.
  54 */
  55static inline int is_zero_ether_addr(const u8 *addr)
  56{
  57        return !(addr[0] | addr[1] | addr[2] | addr[3] | addr[4] | addr[5]);
  58}
  59
  60/**
  61 * is_multicast_ether_addr - Determine if the Ethernet address is a multicast.
  62 * @addr: Pointer to a six-byte array containing the Ethernet address
  63 *
  64 * Return true if the address is a multicast address.
  65 * By definition the broadcast address is also a multicast address.
  66 */
  67static inline int is_multicast_ether_addr(const u8 *addr)
  68{
  69        return (0x01 & addr[0]);
  70}
  71
  72/**
  73 * is_local_ether_addr - Determine if the Ethernet address is locally-assigned one (IEEE 802).
  74 * @addr: Pointer to a six-byte array containing the Ethernet address
  75 *
  76 * Return true if the address is a local address.
  77 */
  78static inline int is_local_ether_addr(const u8 *addr)
  79{
  80        return (0x02 & addr[0]);
  81}
  82
  83/**
  84 * is_broadcast_ether_addr - Determine if the Ethernet address is broadcast
  85 * @addr: Pointer to a six-byte array containing the Ethernet address
  86 *
  87 * Return true if the address is the broadcast address.
  88 */
  89static inline int is_broadcast_ether_addr(const u8 *addr)
  90{
  91        return (addr[0] & addr[1] & addr[2] & addr[3] & addr[4] & addr[5]) == 0xff;
  92}
  93
  94/**
  95 * is_valid_ether_addr - Determine if the given Ethernet address is valid
  96 * @addr: Pointer to a six-byte array containing the Ethernet address
  97 *
  98 * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not
  99 * a multicast address, and is not FF:FF:FF:FF:FF:FF.
 100 *
 101 * Return true if the address is valid.
 102 */
 103static inline int is_valid_ether_addr(const u8 *addr)
 104{
 105        /* FF:FF:FF:FF:FF:FF is a multicast address so we don't need to
 106         * explicitly check for it here. */
 107        return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr);
 108}
 109
 110/**
 111 * random_ether_addr - Generate software assigned random Ethernet address
 112 * @addr: Pointer to a six-byte array containing the Ethernet address
 113 *
 114 * Generate a random Ethernet address (MAC) that is not multicast
 115 * and has the local assigned bit set.
 116 */
 117static inline void random_ether_addr(u8 *addr)
 118{
 119        get_random_bytes (addr, ETH_ALEN);
 120        addr [0] &= 0xfe;       /* clear multicast bit */
 121        addr [0] |= 0x02;       /* set local assignment bit (IEEE802) */
 122}
 123
 124/**
 125 * compare_ether_addr - Compare two Ethernet addresses
 126 * @addr1: Pointer to a six-byte array containing the Ethernet address
 127 * @addr2: Pointer other six-byte array containing the Ethernet address
 128 *
 129 * Compare two ethernet addresses, returns 0 if equal
 130 */
 131static inline unsigned compare_ether_addr(const u8 *addr1, const u8 *addr2)
 132{
 133        const u16 *a = (const u16 *) addr1;
 134        const u16 *b = (const u16 *) addr2;
 135
 136        BUILD_BUG_ON(ETH_ALEN != 6);
 137        return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) != 0;
 138}
 139#endif  /* __KERNEL__ */
 140
 141#endif  /* _LINUX_ETHERDEVICE_H */
 142