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 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  */
  78 static 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  */
  89 static 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  */
 103 static 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  */
 117 static 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  */
 131 static 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 */