/*
   * 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, __be16 type);

  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_mqs(int sizeof_priv, unsigned int txqs,
  					    unsigned int rxqs);

  #define alloc_etherdev(sizeof_priv) alloc_etherdev_mq(sizeof_priv, 1)

  #define alloc_etherdev_mq(sizeof_priv, count) alloc_etherdev_mqs(sizeof_priv, count, count)

  
  /**

   * 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_unicast_ether_addr - Determine if the Ethernet address is unicast
   * @addr: Pointer to a six-byte array containing the Ethernet address
   *
   * Return true if the address is a unicast address.
   */
  static inline int is_unicast_ether_addr(const u8 *addr)
  {
  	return !is_multicast_ether_addr(addr);
  }
  
  /**

   * 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) */
  }

  
  /**

   * dev_hw_addr_random - Create random MAC and set device flag
   * @dev: pointer to net_device structure

   * @hwaddr: Pointer to a six-byte array containing the Ethernet address

   *
   * Generate random MAC to be used by a device and set addr_assign_type
   * so the state can be read by sysfs and be used by udev.
   */
  static inline void dev_hw_addr_random(struct net_device *dev, u8 *hwaddr)
  {
  	dev->addr_assign_type |= NET_ADDR_RANDOM;
  	random_ether_addr(hwaddr);
  }
  
  /**

   * 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
  }

  
  /**
   * is_etherdev_addr - Tell if given Ethernet address belongs to the device.
   * @dev: Pointer to a device structure
   * @addr: Pointer to a six-byte array containing the Ethernet address
   *
   * Compare passed address with all addresses of the device. Return true if the
   * address if one of the device addresses.
   *
   * Note that this function calls compare_ether_addr_64bits() so take care of
   * the right padding.
   */
  static inline bool is_etherdev_addr(const struct net_device *dev,
  				    const u8 addr[6 + 2])
  {
  	struct netdev_hw_addr *ha;
  	int res = 1;
  
  	rcu_read_lock();
  	for_each_dev_addr(dev, ha) {
  		res = compare_ether_addr_64bits(addr, ha->addr);
  		if (!res)
  			break;
  	}
  	rcu_read_unlock();
  	return !res;
  }

  #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 unsigned long compare_ether_header(const void *a, const void *b)

  {

  #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
  	unsigned long fold;
  
  	/*
  	 * We want to compare 14 bytes:
  	 *  [a0 ... a13] ^ [b0 ... b13]
  	 * Use two long XOR, ORed together, with an overlap of two bytes.
  	 *  [a0  a1  a2  a3  a4  a5  a6  a7 ] ^ [b0  b1  b2  b3  b4  b5  b6  b7 ] |
  	 *  [a6  a7  a8  a9  a10 a11 a12 a13] ^ [b6  b7  b8  b9  b10 b11 b12 b13]
  	 * This means the [a6 a7] ^ [b6 b7] part is done two times.
  	*/
  	fold = *(unsigned long *)a ^ *(unsigned long *)b;
  	fold |= *(unsigned long *)(a + 6) ^ *(unsigned long *)(b + 6);
  	return fold;
  #else

  	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

  }

  #endif	/* _LINUX_ETHERDEVICE_H */