kernel_optimize_test/include/linux/etherdevice.h
Stefan Assmann c1f79426e2 sysfs: add attribute to indicate hw address assignment type
Add addr_assign_type to struct net_device and expose it via sysfs.
This new attribute has the purpose of giving user-space the ability to
distinguish between different assignment types of MAC addresses.

For example user-space can treat NICs with randomly generated MAC
addresses differently than NICs that have permanent (locally assigned)
MAC addresses.
For the former udev could write a persistent net rule by matching the
device path instead of the MAC address.
There's also the case of devices that 'steal' MAC addresses from slave
devices. In which it is also be beneficial for user-space to be aware
of the fact.

This patch also introduces a helper function to assist adoption of
drivers that generate MAC addresses randomly.

Signed-off-by: Stefan Assmann <sassmann@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-24 20:49:29 -07:00

250 lines
7.7 KiB
C

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