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