2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
6 * Ethernet-type device handling.
8 * Version: @(#)eth.c 1.0.7 05/25/93
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Mark Evans, <evansmp@uhura.aston.ac.uk>
13 * Florian La Roche, <rzsfl@rz.uni-sb.de>
14 * Alan Cox, <gw4pts@gw4pts.ampr.org>
17 * Mr Linux : Arp problems
18 * Alan Cox : Generic queue tidyup (very tiny here)
19 * Alan Cox : eth_header ntohs should be htons
20 * Alan Cox : eth_rebuild_header missing an htons and
22 * Tegge : Arp bug fixes.
23 * Florian : Removed many unnecessary functions, code cleanup
24 * and changes for new arp and skbuff.
25 * Alan Cox : Redid header building to reflect new format.
26 * Alan Cox : ARP only when compiled with CONFIG_INET
27 * Greg Page : 802.2 and SNAP stuff.
28 * Alan Cox : MAC layer pointers/new format.
29 * Paul Gortmaker : eth_copy_and_sum shouldn't csum padding.
30 * Alan Cox : Protect against forwarding explosions with
31 * older network drivers and IFF_ALLMULTI.
32 * Christer Weinigel : Better rebuild header message.
33 * Andrew Morton : 26Feb01: kill ether_setup() - use netdev_boot_setup().
35 * This program is free software; you can redistribute it and/or
36 * modify it under the terms of the GNU General Public License
37 * as published by the Free Software Foundation; either version
38 * 2 of the License, or (at your option) any later version.
40 #include <linux/module.h>
41 #include <linux/types.h>
42 #include <linux/kernel.h>
43 #include <linux/string.h>
45 #include <linux/socket.h>
47 #include <linux/inet.h>
49 #include <linux/netdevice.h>
50 #include <linux/etherdevice.h>
51 #include <linux/skbuff.h>
52 #include <linux/errno.h>
53 #include <linux/init.h>
54 #include <linux/if_ether.h>
55 #include <linux/of_net.h>
56 #include <linux/pci.h>
63 #include <net/flow_dissector.h>
64 #include <linux/uaccess.h>
66 __setup("ether=", netdev_boot_setup
);
69 * eth_header - create the Ethernet header
70 * @skb: buffer to alter
72 * @type: Ethernet type field
73 * @daddr: destination address (NULL leave destination address)
74 * @saddr: source address (NULL use device source address)
75 * @len: packet length (<= skb->len)
78 * Set the protocol type. For a packet of type ETH_P_802_3/2 we put the length
81 int eth_header(struct sk_buff
*skb
, struct net_device
*dev
,
83 const void *daddr
, const void *saddr
, unsigned int len
)
85 struct ethhdr
*eth
= (struct ethhdr
*)skb_push(skb
, ETH_HLEN
);
87 if (type
!= ETH_P_802_3
&& type
!= ETH_P_802_2
)
88 eth
->h_proto
= htons(type
);
90 eth
->h_proto
= htons(len
);
93 * Set the source hardware address.
97 saddr
= dev
->dev_addr
;
98 memcpy(eth
->h_source
, saddr
, ETH_ALEN
);
101 memcpy(eth
->h_dest
, daddr
, ETH_ALEN
);
106 * Anyway, the loopback-device should never use this function...
109 if (dev
->flags
& (IFF_LOOPBACK
| IFF_NOARP
)) {
110 eth_zero_addr(eth
->h_dest
);
116 EXPORT_SYMBOL(eth_header
);
119 * eth_get_headlen - determine the length of header for an ethernet frame
120 * @data: pointer to start of frame
121 * @len: total length of frame
123 * Make a best effort attempt to pull the length for all of the headers for
124 * a given frame in a linear buffer.
126 u32
eth_get_headlen(void *data
, unsigned int len
)
128 const struct ethhdr
*eth
= (const struct ethhdr
*)data
;
129 struct flow_keys keys
;
131 /* this should never happen, but better safe than sorry */
132 if (unlikely(len
< sizeof(*eth
)))
135 /* parse any remaining L2/L3 headers, check for L4 */
136 if (!skb_flow_dissect_flow_keys_buf(&keys
, data
, eth
->h_proto
,
137 sizeof(*eth
), len
, 0))
138 return max_t(u32
, keys
.control
.thoff
, sizeof(*eth
));
140 /* parse for any L4 headers */
141 return min_t(u32
, __skb_get_poff(NULL
, data
, &keys
, len
), len
);
143 EXPORT_SYMBOL(eth_get_headlen
);
146 * eth_type_trans - determine the packet's protocol ID.
147 * @skb: received socket data
148 * @dev: receiving network device
150 * The rule here is that we
151 * assume 802.3 if the type field is short enough to be a length.
152 * This is normal practice and works for any 'now in use' protocol.
154 __be16
eth_type_trans(struct sk_buff
*skb
, struct net_device
*dev
)
156 unsigned short _service_access_point
;
157 const unsigned short *sap
;
158 const struct ethhdr
*eth
;
161 skb_reset_mac_header(skb
);
163 eth
= (struct ethhdr
*)skb
->data
;
164 skb_pull_inline(skb
, ETH_HLEN
);
166 if (unlikely(is_multicast_ether_addr_64bits(eth
->h_dest
))) {
167 if (ether_addr_equal_64bits(eth
->h_dest
, dev
->broadcast
))
168 skb
->pkt_type
= PACKET_BROADCAST
;
170 skb
->pkt_type
= PACKET_MULTICAST
;
172 else if (unlikely(!ether_addr_equal_64bits(eth
->h_dest
,
174 skb
->pkt_type
= PACKET_OTHERHOST
;
177 * Some variants of DSA tagging don't have an ethertype field
178 * at all, so we check here whether one of those tagging
179 * variants has been configured on the receiving interface,
180 * and if so, set skb->protocol without looking at the packet.
182 if (unlikely(netdev_uses_dsa(dev
)))
183 return htons(ETH_P_XDSA
);
185 if (likely(eth_proto_is_802_3(eth
->h_proto
)))
189 * This is a magic hack to spot IPX packets. Older Novell breaks
190 * the protocol design and runs IPX over 802.3 without an 802.2 LLC
191 * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
192 * won't work for fault tolerant netware but does for the rest.
194 sap
= skb_header_pointer(skb
, 0, sizeof(*sap
), &_service_access_point
);
195 if (sap
&& *sap
== 0xFFFF)
196 return htons(ETH_P_802_3
);
201 return htons(ETH_P_802_2
);
203 EXPORT_SYMBOL(eth_type_trans
);
206 * eth_header_parse - extract hardware address from packet
207 * @skb: packet to extract header from
208 * @haddr: destination buffer
210 int eth_header_parse(const struct sk_buff
*skb
, unsigned char *haddr
)
212 const struct ethhdr
*eth
= eth_hdr(skb
);
213 memcpy(haddr
, eth
->h_source
, ETH_ALEN
);
216 EXPORT_SYMBOL(eth_header_parse
);
219 * eth_header_cache - fill cache entry from neighbour
220 * @neigh: source neighbour
221 * @hh: destination cache entry
222 * @type: Ethernet type field
224 * Create an Ethernet header template from the neighbour.
226 int eth_header_cache(const struct neighbour
*neigh
, struct hh_cache
*hh
, __be16 type
)
229 const struct net_device
*dev
= neigh
->dev
;
231 eth
= (struct ethhdr
*)
232 (((u8
*) hh
->hh_data
) + (HH_DATA_OFF(sizeof(*eth
))));
234 if (type
== htons(ETH_P_802_3
))
238 memcpy(eth
->h_source
, dev
->dev_addr
, ETH_ALEN
);
239 memcpy(eth
->h_dest
, neigh
->ha
, ETH_ALEN
);
240 hh
->hh_len
= ETH_HLEN
;
243 EXPORT_SYMBOL(eth_header_cache
);
246 * eth_header_cache_update - update cache entry
247 * @hh: destination cache entry
248 * @dev: network device
249 * @haddr: new hardware address
251 * Called by Address Resolution module to notify changes in address.
253 void eth_header_cache_update(struct hh_cache
*hh
,
254 const struct net_device
*dev
,
255 const unsigned char *haddr
)
257 memcpy(((u8
*) hh
->hh_data
) + HH_DATA_OFF(sizeof(struct ethhdr
)),
260 EXPORT_SYMBOL(eth_header_cache_update
);
263 * eth_prepare_mac_addr_change - prepare for mac change
264 * @dev: network device
267 int eth_prepare_mac_addr_change(struct net_device
*dev
, void *p
)
269 struct sockaddr
*addr
= p
;
271 if (!(dev
->priv_flags
& IFF_LIVE_ADDR_CHANGE
) && netif_running(dev
))
273 if (!is_valid_ether_addr(addr
->sa_data
))
274 return -EADDRNOTAVAIL
;
277 EXPORT_SYMBOL(eth_prepare_mac_addr_change
);
280 * eth_commit_mac_addr_change - commit mac change
281 * @dev: network device
284 void eth_commit_mac_addr_change(struct net_device
*dev
, void *p
)
286 struct sockaddr
*addr
= p
;
288 memcpy(dev
->dev_addr
, addr
->sa_data
, ETH_ALEN
);
290 EXPORT_SYMBOL(eth_commit_mac_addr_change
);
293 * eth_mac_addr - set new Ethernet hardware address
294 * @dev: network device
297 * Change hardware address of device.
299 * This doesn't change hardware matching, so needs to be overridden
300 * for most real devices.
302 int eth_mac_addr(struct net_device
*dev
, void *p
)
306 ret
= eth_prepare_mac_addr_change(dev
, p
);
309 eth_commit_mac_addr_change(dev
, p
);
312 EXPORT_SYMBOL(eth_mac_addr
);
315 * eth_change_mtu - set new MTU size
316 * @dev: network device
317 * @new_mtu: new Maximum Transfer Unit
319 * Allow changing MTU size. Needs to be overridden for devices
320 * supporting jumbo frames.
322 int eth_change_mtu(struct net_device
*dev
, int new_mtu
)
324 if (new_mtu
< 68 || new_mtu
> ETH_DATA_LEN
)
329 EXPORT_SYMBOL(eth_change_mtu
);
331 int eth_validate_addr(struct net_device
*dev
)
333 if (!is_valid_ether_addr(dev
->dev_addr
))
334 return -EADDRNOTAVAIL
;
338 EXPORT_SYMBOL(eth_validate_addr
);
340 const struct header_ops eth_header_ops ____cacheline_aligned
= {
341 .create
= eth_header
,
342 .parse
= eth_header_parse
,
343 .cache
= eth_header_cache
,
344 .cache_update
= eth_header_cache_update
,
348 * ether_setup - setup Ethernet network device
349 * @dev: network device
351 * Fill in the fields of the device structure with Ethernet-generic values.
353 void ether_setup(struct net_device
*dev
)
355 dev
->header_ops
= ð_header_ops
;
356 dev
->type
= ARPHRD_ETHER
;
357 dev
->hard_header_len
= ETH_HLEN
;
358 dev
->mtu
= ETH_DATA_LEN
;
359 dev
->addr_len
= ETH_ALEN
;
360 dev
->tx_queue_len
= 1000; /* Ethernet wants good queues */
361 dev
->flags
= IFF_BROADCAST
|IFF_MULTICAST
;
362 dev
->priv_flags
|= IFF_TX_SKB_SHARING
;
364 eth_broadcast_addr(dev
->broadcast
);
367 EXPORT_SYMBOL(ether_setup
);
370 * alloc_etherdev_mqs - Allocates and sets up an Ethernet device
371 * @sizeof_priv: Size of additional driver-private structure to be allocated
372 * for this Ethernet device
373 * @txqs: The number of TX queues this device has.
374 * @rxqs: The number of RX queues this device has.
376 * Fill in the fields of the device structure with Ethernet-generic
377 * values. Basically does everything except registering the device.
379 * Constructs a new net device, complete with a private data area of
380 * size (sizeof_priv). A 32-byte (not bit) alignment is enforced for
381 * this private data area.
384 struct net_device
*alloc_etherdev_mqs(int sizeof_priv
, unsigned int txqs
,
387 return alloc_netdev_mqs(sizeof_priv
, "eth%d", NET_NAME_UNKNOWN
,
388 ether_setup
, txqs
, rxqs
);
390 EXPORT_SYMBOL(alloc_etherdev_mqs
);
392 ssize_t
sysfs_format_mac(char *buf
, const unsigned char *addr
, int len
)
394 return scnprintf(buf
, PAGE_SIZE
, "%*phC\n", len
, addr
);
396 EXPORT_SYMBOL(sysfs_format_mac
);
398 struct sk_buff
**eth_gro_receive(struct sk_buff
**head
,
401 struct sk_buff
*p
, **pp
= NULL
;
402 struct ethhdr
*eh
, *eh2
;
403 unsigned int hlen
, off_eth
;
404 const struct packet_offload
*ptype
;
408 off_eth
= skb_gro_offset(skb
);
409 hlen
= off_eth
+ sizeof(*eh
);
410 eh
= skb_gro_header_fast(skb
, off_eth
);
411 if (skb_gro_header_hard(skb
, hlen
)) {
412 eh
= skb_gro_header_slow(skb
, hlen
, off_eth
);
419 for (p
= *head
; p
; p
= p
->next
) {
420 if (!NAPI_GRO_CB(p
)->same_flow
)
423 eh2
= (struct ethhdr
*)(p
->data
+ off_eth
);
424 if (compare_ether_header(eh
, eh2
)) {
425 NAPI_GRO_CB(p
)->same_flow
= 0;
433 ptype
= gro_find_receive_by_type(type
);
439 skb_gro_pull(skb
, sizeof(*eh
));
440 skb_gro_postpull_rcsum(skb
, eh
, sizeof(*eh
));
441 pp
= ptype
->callbacks
.gro_receive(head
, skb
);
446 NAPI_GRO_CB(skb
)->flush
|= flush
;
450 EXPORT_SYMBOL(eth_gro_receive
);
452 int eth_gro_complete(struct sk_buff
*skb
, int nhoff
)
454 struct ethhdr
*eh
= (struct ethhdr
*)(skb
->data
+ nhoff
);
455 __be16 type
= eh
->h_proto
;
456 struct packet_offload
*ptype
;
459 if (skb
->encapsulation
)
460 skb_set_inner_mac_header(skb
, nhoff
);
463 ptype
= gro_find_complete_by_type(type
);
465 err
= ptype
->callbacks
.gro_complete(skb
, nhoff
+
466 sizeof(struct ethhdr
));
471 EXPORT_SYMBOL(eth_gro_complete
);
473 static struct packet_offload eth_packet_offload __read_mostly
= {
474 .type
= cpu_to_be16(ETH_P_TEB
),
477 .gro_receive
= eth_gro_receive
,
478 .gro_complete
= eth_gro_complete
,
482 static int __init
eth_offload_init(void)
484 dev_add_offload(ð_packet_offload
);
489 fs_initcall(eth_offload_init
);
491 unsigned char * __weak
arch_get_platform_mac_address(void)
496 int eth_platform_get_mac_address(struct device
*dev
, u8
*mac_addr
)
498 const unsigned char *addr
;
499 struct device_node
*dp
;
502 dp
= pci_device_to_OF_node(to_pci_dev(dev
));
508 addr
= of_get_mac_address(dp
);
510 addr
= arch_get_platform_mac_address();
515 ether_addr_copy(mac_addr
, addr
);
518 EXPORT_SYMBOL(eth_platform_get_mac_address
);