/* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. NET is implemented using the BSD Socket * interface as the means of communication with the user level. * * Definitions for the Ethernet handlers. * * Version: @(#)eth.h 1.0.4 05/13/93 * * Authors: Ross Biro * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> * * Relocated to include/linux where it belongs by Alan Cox * <gw4pts@gw4pts.ampr.org> * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * * WARNING: This move may well be temporary. This file will get merged with others RSN. * */ #ifndef _LINUX_ETHERDEVICE_H #define _LINUX_ETHERDEVICE_H #include <linux/if_ether.h> #include <linux/netdevice.h> #include <linux/random.h> #include <asm/unaligned.h> #ifdef __KERNEL__ extern __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev); extern const struct header_ops eth_header_ops; extern int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *daddr, const void *saddr, unsigned len); extern int eth_rebuild_header(struct sk_buff *skb); extern int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr); extern int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh); extern void eth_header_cache_update(struct hh_cache *hh, const struct net_device *dev, const unsigned char *haddr); extern int eth_mac_addr(struct net_device *dev, void *p); extern int eth_change_mtu(struct net_device *dev, int new_mtu); extern int eth_validate_addr(struct net_device *dev); extern struct net_device *alloc_etherdev_mq(int sizeof_priv, unsigned int queue_count); #define alloc_etherdev(sizeof_priv) alloc_etherdev_mq(sizeof_priv, 1) /** * is_zero_ether_addr - Determine if give Ethernet address is all zeros. * @addr: Pointer to a six-byte array containing the Ethernet address * * Return true if the address is all zeroes. */ static inline int is_zero_ether_addr(const u8 *addr) { return !(addr[0] | addr[1] | addr[2] | addr[3] | addr[4] | addr[5]); } /** * is_multicast_ether_addr - Determine if the Ethernet address is a multicast. * @addr: Pointer to a six-byte array containing the Ethernet address * * Return true if the address is a multicast address. * By definition the broadcast address is also a multicast address. */ static inline int is_multicast_ether_addr(const u8 *addr) { return (0x01 & addr[0]); } /** * is_local_ether_addr - Determine if the Ethernet address is locally-assigned one (IEEE 802). * @addr: Pointer to a six-byte array containing the Ethernet address * * Return true if the address is a local address. */ static inline int is_local_ether_addr(const u8 *addr) { return (0x02 & addr[0]); } /** * is_broadcast_ether_addr - Determine if the Ethernet address is broadcast * @addr: Pointer to a six-byte array containing the Ethernet address * * Return true if the address is the broadcast address. */ static inline int is_broadcast_ether_addr(const u8 *addr) { return (addr[0] & addr[1] & addr[2] & addr[3] & addr[4] & addr[5]) == 0xff; } /** * is_valid_ether_addr - Determine if the given Ethernet address is valid * @addr: Pointer to a six-byte array containing the Ethernet address * * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not * a multicast address, and is not FF:FF:FF:FF:FF:FF. * * Return true if the address is valid. */ static inline int is_valid_ether_addr(const u8 *addr) { /* FF:FF:FF:FF:FF:FF is a multicast address so we don't need to * explicitly check for it here. */ return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr); } /** * random_ether_addr - Generate software assigned random Ethernet address * @addr: Pointer to a six-byte array containing the Ethernet address * * Generate a random Ethernet address (MAC) that is not multicast * and has the local assigned bit set. */ static inline void random_ether_addr(u8 *addr) { get_random_bytes (addr, ETH_ALEN); addr [0] &= 0xfe; /* clear multicast bit */ addr [0] |= 0x02; /* set local assignment bit (IEEE802) */ } /** * compare_ether_addr - Compare two Ethernet addresses * @addr1: Pointer to a six-byte array containing the Ethernet address * @addr2: Pointer other six-byte array containing the Ethernet address * * Compare two ethernet addresses, returns 0 if equal */ static inline unsigned compare_ether_addr(const u8 *addr1, const u8 *addr2) { const u16 *a = (const u16 *) addr1; const u16 *b = (const u16 *) addr2; BUILD_BUG_ON(ETH_ALEN != 6); return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) != 0; } static inline unsigned long zap_last_2bytes(unsigned long value) { #ifdef __BIG_ENDIAN return value >> 16; #else return value << 16; #endif } /** * compare_ether_addr_64bits - Compare two Ethernet addresses * @addr1: Pointer to an array of 8 bytes * @addr2: Pointer to an other array of 8 bytes * * Compare two ethernet addresses, returns 0 if equal. * Same result than "memcmp(addr1, addr2, ETH_ALEN)" but without conditional * branches, and possibly long word memory accesses on CPU allowing cheap * unaligned memory reads. * arrays = { byte1, byte2, byte3, byte4, byte6, byte7, pad1, pad2} * * Please note that alignment of addr1 & addr2 is only guaranted to be 16 bits. */ static inline unsigned compare_ether_addr_64bits(const u8 addr1[6+2], const u8 addr2[6+2]) { #ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS unsigned long fold = ((*(unsigned long *)addr1) ^ (*(unsigned long *)addr2)); if (sizeof(fold) == 8) return zap_last_2bytes(fold) != 0; fold |= zap_last_2bytes((*(unsigned long *)(addr1 + 4)) ^ (*(unsigned long *)(addr2 + 4))); return fold != 0; #else return compare_ether_addr(addr1, addr2); #endif } #endif /* __KERNEL__ */ /** * compare_ether_header - Compare two Ethernet headers * @a: Pointer to Ethernet header * @b: Pointer to Ethernet header * * Compare two ethernet headers, returns 0 if equal. * This assumes that the network header (i.e., IP header) is 4-byte * aligned OR the platform can handle unaligned access. This is the * case for all packets coming into netif_receive_skb or similar * entry points. */ static inline int compare_ether_header(const void *a, const void *b) { u32 *a32 = (u32 *)((u8 *)a + 2); u32 *b32 = (u32 *)((u8 *)b + 2); return (*(u16 *)a ^ *(u16 *)b) | (a32[0] ^ b32[0]) | (a32[1] ^ b32[1]) | (a32[2] ^ b32[2]); } #endif /* _LINUX_ETHERDEVICE_H */