- 根目录:
- include
- linux
- etherdevice.h
/*
* 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.
*
*/
#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>
#include <asm/bitsperlong.h>
#ifdef __KERNEL__
__be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev);
extern const struct header_ops eth_header_ops;
int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type,
const void *daddr, const void *saddr, unsigned len);
int eth_rebuild_header(struct sk_buff *skb);
int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr);
int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh,
__be16 type);
void eth_header_cache_update(struct hh_cache *hh, const struct net_device *dev,
const unsigned char *haddr);
int eth_prepare_mac_addr_change(struct net_device *dev, void *p);
void eth_commit_mac_addr_change(struct net_device *dev, void *p);
int eth_mac_addr(struct net_device *dev, void *p);
int eth_change_mtu(struct net_device *dev, int new_mtu);
int eth_validate_addr(struct net_device *dev);
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)
/* Reserved Ethernet Addresses per IEEE 802.1Q */
static const u8 eth_reserved_addr_base[ETH_ALEN] __aligned(2) =
{ 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
/**
* is_link_local_ether_addr - Determine if given Ethernet address is link-local
* @addr: Pointer to a six-byte array containing the Ethernet address
*
* Return true if address is link local reserved addr (01:80:c2:00:00:0X) per
* IEEE 802.1Q 8.6.3 Frame filtering.
*
* Please note: addr must be aligned to u16.
*/
static inline bool is_link_local_ether_addr(const u8 *addr)
{
__be16 *a = (__be16 *)addr;
static const __be16 *b = (const __be16 *)eth_reserved_addr_base;
static const __be16 m = cpu_to_be16(0xfff0);
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
return (((*(const u32 *)addr) ^ (*(const u32 *)b)) |
((a[2] ^ b[2]) & m)) == 0;
#else
return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | ((a[2] ^ b[2]) & m)) == 0;
#endif
}
/**
* 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.
*
* Please note: addr must be aligned to u16.
*/
static inline bool is_zero_ether_addr(const u8 *addr)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
return ((*(const u32 *)addr) | (*(const u16 *)(addr + 4))) == 0;
#else
return (*(const u16 *)(addr + 0) |
*(const u16 *)(addr + 2) |
*(const u16 *)(addr + 4)) == 0;
#endif
}
/**
* 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 bool 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 bool 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.
*
* Please note: addr must be aligned to u16.
*/
static inline bool is_broadcast_ether_addr(const u8 *addr)
{
return (*(const u16 *)(addr + 0) &
*(const u16 *)(addr + 2) &
*(const u16 *)(addr + 4)) == 0xffff;
}
/**
* 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 bool 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.
*
* Please note: addr must be aligned to u16.
*/
static inline bool 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);
}
/**
* eth_random_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 eth_random_addr(u8 *addr)
{
get_random_bytes(addr, ETH_ALEN);
addr[0] &= 0xfe; /* clear multicast bit */
addr[0] |= 0x02; /* set local assignment bit (IEEE802) */
}
#define random_ether_addr(addr) eth_random_addr(addr)
/**
* eth_broadcast_addr - Assign broadcast address
* @addr: Pointer to a six-byte array containing the Ethernet address
*
* Assign the broadcast address to the given address array.
*/
static inline void eth_broadcast_addr(u8 *addr)
{
memset(addr, 0xff, ETH_ALEN);
}
/**
* eth_zero_addr - Assign zero address
* @addr: Pointer to a six-byte array containing the Ethernet address
*
* Assign the zero address to the given address array.
*/
static inline void eth_zero_addr(u8 *addr)
{
memset(addr, 0x00, ETH_ALEN);
}
/**
* eth_hw_addr_random - Generate software assigned random Ethernet and
* set device flag
* @dev: pointer to net_device structure
*
* Generate a random Ethernet address (MAC) to be used by a net device
* and set addr_assign_type so the state can be read by sysfs and be
* used by userspace.
*/
static inline void eth_hw_addr_random(struct net_device *dev)
{
dev->addr_assign_type = NET_ADDR_RANDOM;
eth_random_addr(dev->dev_addr);
}
/**
* ether_addr_copy - Copy an Ethernet address
* @dst: Pointer to a six-byte array Ethernet address destination
* @src: Pointer to a six-byte array Ethernet address source
*
* Please note: dst & src must both be aligned to u16.
*/
static inline void ether_addr_copy(u8 *dst, const u8 *src)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
*(u32 *)dst = *(const u32 *)src;
*(u16 *)(dst + 4) = *(const u16 *)(src + 4);
#else
u16 *a = (u16 *)dst;
const u16 *b = (const u16 *)src;
a[0] = b[0];
a[1] = b[1];
a[2] = b[2];
#endif
}
/**
* eth_hw_addr_inherit - Copy dev_addr from another net_device
* @dst: pointer to net_device to copy dev_addr to
* @src: pointer to net_device to copy dev_addr from
*
* Copy the Ethernet address from one net_device to another along with
* the address attributes (addr_assign_type).
*/
static inline void eth_hw_addr_inherit(struct net_device *dst,
struct net_device *src)
{
dst->addr_assign_type = src->addr_assign_type;
ether_addr_copy(dst->dev_addr, src->dev_addr);
}
/**
* ether_addr_equal - 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 true if equal
*
* Please note: addr1 & addr2 must both be aligned to u16.
*/
static inline bool ether_addr_equal(const u8 *addr1, const u8 *addr2)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
u32 fold = ((*(const u32 *)addr1) ^ (*(const u32 *)addr2)) |
((*(const u16 *)(addr1 + 4)) ^ (*(const u16 *)(addr2 + 4)));
return fold == 0;
#else
const u16 *a = (const u16 *)addr1;
const u16 *b = (const u16 *)addr2;
return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) == 0;
#endif
}
/**
* ether_addr_equal_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 true if equal, false otherwise.
*
* The function doesn't need any conditional branches and possibly uses
* word memory accesses on CPU allowing cheap unaligned memory reads.
* arrays = { byte1, byte2, byte3, byte4, byte5, byte6, pad1, pad2 }
*
* Please note that alignment of addr1 & addr2 are only guaranteed to be 16 bits.
*/
static inline bool ether_addr_equal_64bits(const u8 addr1[6+2],
const u8 addr2[6+2])
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
u64 fold = (*(const u64 *)addr1) ^ (*(const u64 *)addr2);
#ifdef __BIG_ENDIAN
return (fold >> 16) == 0;
#else
return (fold << 16) == 0;
#endif
#else
return ether_addr_equal(addr1, addr2);
#endif
}
/**
* ether_addr_equal_unaligned - Compare two not u16 aligned 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 true if equal
*
* Please note: Use only when any Ethernet address may not be u16 aligned.
*/
static inline bool ether_addr_equal_unaligned(const u8 *addr1, const u8 *addr2)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
return ether_addr_equal(addr1, addr2);
#else
return memcmp(addr1, addr2, ETH_ALEN) == 0;
#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 ether_addr_equal_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;
bool res = false;
rcu_read_lock();
for_each_dev_addr(dev, ha) {
res = ether_addr_equal_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 */