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, <[email protected]> 12 * 13 * Relocated to include/linux where it belongs by Alan Cox 14 * <[email protected]> 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 */ 143