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