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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * Ethernet-type device handling.
8 *
9 * Version: @(#)eth.c 1.0.7 05/25/93
10 *
11 * Authors: Ross Biro
12 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
13 * Mark Evans, <evansmp@uhura.aston.ac.uk>
14 * Florian La Roche, <rzsfl@rz.uni-sb.de>
15 * Alan Cox, <gw4pts@gw4pts.ampr.org>
16 *
17 * Fixes:
18 * Mr Linux : Arp problems
19 * Alan Cox : Generic queue tidyup (very tiny here)
20 * Alan Cox : eth_header ntohs should be htons
21 * Alan Cox : eth_rebuild_header missing an htons and
22 * minor other things.
23 * Tegge : Arp bug fixes.
24 * Florian : Removed many unnecessary functions, code cleanup
25 * and changes for new arp and skbuff.
26 * Alan Cox : Redid header building to reflect new format.
27 * Alan Cox : ARP only when compiled with CONFIG_INET
28 * Greg Page : 802.2 and SNAP stuff.
29 * Alan Cox : MAC layer pointers/new format.
30 * Paul Gortmaker : eth_copy_and_sum shouldn't csum padding.
31 * Alan Cox : Protect against forwarding explosions with
32 * older network drivers and IFF_ALLMULTI.
33 * Christer Weinigel : Better rebuild header message.
34 * Andrew Morton : 26Feb01: kill ether_setup() - use netdev_boot_setup().
35 */
36#include <linux/module.h>
37#include <linux/types.h>
38#include <linux/kernel.h>
39#include <linux/string.h>
40#include <linux/mm.h>
41#include <linux/socket.h>
42#include <linux/in.h>
43#include <linux/inet.h>
44#include <linux/ip.h>
45#include <linux/netdevice.h>
46#include <linux/nvmem-consumer.h>
47#include <linux/etherdevice.h>
48#include <linux/skbuff.h>
49#include <linux/errno.h>
50#include <linux/init.h>
51#include <linux/if_ether.h>
52#include <linux/of_net.h>
53#include <linux/pci.h>
54#include <net/dst.h>
55#include <net/arp.h>
56#include <net/sock.h>
57#include <net/ipv6.h>
58#include <net/ip.h>
59#include <net/dsa.h>
60#include <net/flow_dissector.h>
61#include <net/gro.h>
62#include <linux/uaccess.h>
63#include <net/pkt_sched.h>
64
65__setup("ether=", netdev_boot_setup);
66
67/**
68 * eth_header - create the Ethernet header
69 * @skb: buffer to alter
70 * @dev: source device
71 * @type: Ethernet type field
72 * @daddr: destination address (NULL leave destination address)
73 * @saddr: source address (NULL use device source address)
74 * @len: packet length (<= skb->len)
75 *
76 *
77 * Set the protocol type. For a packet of type ETH_P_802_3/2 we put the length
78 * in here instead.
79 */
80int eth_header(struct sk_buff *skb, struct net_device *dev,
81 unsigned short type,
82 const void *daddr, const void *saddr, unsigned int len)
83{
84 struct ethhdr *eth = skb_push(skb, ETH_HLEN);
85
86 if (type != ETH_P_802_3 && type != ETH_P_802_2)
87 eth->h_proto = htons(type);
88 else
89 eth->h_proto = htons(len);
90
91 /*
92 * Set the source hardware address.
93 */
94
95 if (!saddr)
96 saddr = dev->dev_addr;
97 memcpy(eth->h_source, saddr, ETH_ALEN);
98
99 if (daddr) {
100 memcpy(eth->h_dest, daddr, ETH_ALEN);
101 return ETH_HLEN;
102 }
103
104 /*
105 * Anyway, the loopback-device should never use this function...
106 */
107
108 if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) {
109 eth_zero_addr(eth->h_dest);
110 return ETH_HLEN;
111 }
112
113 return -ETH_HLEN;
114}
115EXPORT_SYMBOL(eth_header);
116
117/**
118 * eth_get_headlen - determine the length of header for an ethernet frame
119 * @dev: pointer to network device
120 * @data: pointer to start of frame
121 * @len: total length of frame
122 *
123 * Make a best effort attempt to pull the length for all of the headers for
124 * a given frame in a linear buffer.
125 */
126u32 eth_get_headlen(const struct net_device *dev, const void *data, u32 len)
127{
128 const unsigned int flags = FLOW_DISSECTOR_F_PARSE_1ST_FRAG;
129 const struct ethhdr *eth = (const struct ethhdr *)data;
130 struct flow_keys_basic keys;
131
132 /* this should never happen, but better safe than sorry */
133 if (unlikely(len < sizeof(*eth)))
134 return len;
135
136 /* parse any remaining L2/L3 headers, check for L4 */
137 if (!skb_flow_dissect_flow_keys_basic(dev_net(dev), NULL, &keys, data,
138 eth->h_proto, sizeof(*eth),
139 len, flags))
140 return max_t(u32, keys.control.thoff, sizeof(*eth));
141
142 /* parse for any L4 headers */
143 return min_t(u32, __skb_get_poff(NULL, data, &keys, len), len);
144}
145EXPORT_SYMBOL(eth_get_headlen);
146
147/**
148 * eth_type_trans - determine the packet's protocol ID.
149 * @skb: received socket data
150 * @dev: receiving network device
151 *
152 * The rule here is that we
153 * assume 802.3 if the type field is short enough to be a length.
154 * This is normal practice and works for any 'now in use' protocol.
155 */
156__be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev)
157{
158 unsigned short _service_access_point;
159 const unsigned short *sap;
160 const struct ethhdr *eth;
161
162 skb->dev = dev;
163 skb_reset_mac_header(skb);
164
165 eth = (struct ethhdr *)skb->data;
166 skb_pull_inline(skb, ETH_HLEN);
167
168 if (unlikely(!ether_addr_equal_64bits(eth->h_dest,
169 dev->dev_addr))) {
170 if (unlikely(is_multicast_ether_addr_64bits(eth->h_dest))) {
171 if (ether_addr_equal_64bits(eth->h_dest, dev->broadcast))
172 skb->pkt_type = PACKET_BROADCAST;
173 else
174 skb->pkt_type = PACKET_MULTICAST;
175 } else {
176 skb->pkt_type = PACKET_OTHERHOST;
177 }
178 }
179
180 /*
181 * Some variants of DSA tagging don't have an ethertype field
182 * at all, so we check here whether one of those tagging
183 * variants has been configured on the receiving interface,
184 * and if so, set skb->protocol without looking at the packet.
185 * The DSA tagging protocol may be able to decode some but not all
186 * traffic (for example only for management). In that case give it the
187 * option to filter the packets from which it can decode source port
188 * information.
189 */
190 if (unlikely(netdev_uses_dsa(dev)) && dsa_can_decode(skb, dev))
191 return htons(ETH_P_XDSA);
192
193 if (likely(eth_proto_is_802_3(eth->h_proto)))
194 return eth->h_proto;
195
196 /*
197 * This is a magic hack to spot IPX packets. Older Novell breaks
198 * the protocol design and runs IPX over 802.3 without an 802.2 LLC
199 * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
200 * won't work for fault tolerant netware but does for the rest.
201 */
202 sap = skb_header_pointer(skb, 0, sizeof(*sap), &_service_access_point);
203 if (sap && *sap == 0xFFFF)
204 return htons(ETH_P_802_3);
205
206 /*
207 * Real 802.2 LLC
208 */
209 return htons(ETH_P_802_2);
210}
211EXPORT_SYMBOL(eth_type_trans);
212
213/**
214 * eth_header_parse - extract hardware address from packet
215 * @skb: packet to extract header from
216 * @haddr: destination buffer
217 */
218int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr)
219{
220 const struct ethhdr *eth = eth_hdr(skb);
221 memcpy(haddr, eth->h_source, ETH_ALEN);
222 return ETH_ALEN;
223}
224EXPORT_SYMBOL(eth_header_parse);
225
226/**
227 * eth_header_cache - fill cache entry from neighbour
228 * @neigh: source neighbour
229 * @hh: destination cache entry
230 * @type: Ethernet type field
231 *
232 * Create an Ethernet header template from the neighbour.
233 */
234int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh, __be16 type)
235{
236 struct ethhdr *eth;
237 const struct net_device *dev = neigh->dev;
238
239 eth = (struct ethhdr *)
240 (((u8 *) hh->hh_data) + (HH_DATA_OFF(sizeof(*eth))));
241
242 if (type == htons(ETH_P_802_3))
243 return -1;
244
245 eth->h_proto = type;
246 memcpy(eth->h_source, dev->dev_addr, ETH_ALEN);
247 memcpy(eth->h_dest, neigh->ha, ETH_ALEN);
248
249 /* Pairs with READ_ONCE() in neigh_resolve_output(),
250 * neigh_hh_output() and neigh_update_hhs().
251 */
252 smp_store_release(&hh->hh_len, ETH_HLEN);
253
254 return 0;
255}
256EXPORT_SYMBOL(eth_header_cache);
257
258/**
259 * eth_header_cache_update - update cache entry
260 * @hh: destination cache entry
261 * @dev: network device
262 * @haddr: new hardware address
263 *
264 * Called by Address Resolution module to notify changes in address.
265 */
266void eth_header_cache_update(struct hh_cache *hh,
267 const struct net_device *dev,
268 const unsigned char *haddr)
269{
270 memcpy(((u8 *) hh->hh_data) + HH_DATA_OFF(sizeof(struct ethhdr)),
271 haddr, ETH_ALEN);
272}
273EXPORT_SYMBOL(eth_header_cache_update);
274
275/**
276 * eth_header_parse_protocol - extract protocol from L2 header
277 * @skb: packet to extract protocol from
278 */
279__be16 eth_header_parse_protocol(const struct sk_buff *skb)
280{
281 const struct ethhdr *eth = eth_hdr(skb);
282
283 return eth->h_proto;
284}
285EXPORT_SYMBOL(eth_header_parse_protocol);
286
287/**
288 * eth_prepare_mac_addr_change - prepare for mac change
289 * @dev: network device
290 * @p: socket address
291 */
292int eth_prepare_mac_addr_change(struct net_device *dev, void *p)
293{
294 struct sockaddr *addr = p;
295
296 if (!(dev->priv_flags & IFF_LIVE_ADDR_CHANGE) && netif_running(dev))
297 return -EBUSY;
298 if (!is_valid_ether_addr(addr->sa_data))
299 return -EADDRNOTAVAIL;
300 return 0;
301}
302EXPORT_SYMBOL(eth_prepare_mac_addr_change);
303
304/**
305 * eth_commit_mac_addr_change - commit mac change
306 * @dev: network device
307 * @p: socket address
308 */
309void eth_commit_mac_addr_change(struct net_device *dev, void *p)
310{
311 struct sockaddr *addr = p;
312
313 memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
314}
315EXPORT_SYMBOL(eth_commit_mac_addr_change);
316
317/**
318 * eth_mac_addr - set new Ethernet hardware address
319 * @dev: network device
320 * @p: socket address
321 *
322 * Change hardware address of device.
323 *
324 * This doesn't change hardware matching, so needs to be overridden
325 * for most real devices.
326 */
327int eth_mac_addr(struct net_device *dev, void *p)
328{
329 int ret;
330
331 ret = eth_prepare_mac_addr_change(dev, p);
332 if (ret < 0)
333 return ret;
334 eth_commit_mac_addr_change(dev, p);
335 return 0;
336}
337EXPORT_SYMBOL(eth_mac_addr);
338
339int eth_validate_addr(struct net_device *dev)
340{
341 if (!is_valid_ether_addr(dev->dev_addr))
342 return -EADDRNOTAVAIL;
343
344 return 0;
345}
346EXPORT_SYMBOL(eth_validate_addr);
347
348const struct header_ops eth_header_ops ____cacheline_aligned = {
349 .create = eth_header,
350 .parse = eth_header_parse,
351 .cache = eth_header_cache,
352 .cache_update = eth_header_cache_update,
353 .parse_protocol = eth_header_parse_protocol,
354};
355
356/**
357 * ether_setup - setup Ethernet network device
358 * @dev: network device
359 *
360 * Fill in the fields of the device structure with Ethernet-generic values.
361 */
362void ether_setup(struct net_device *dev)
363{
364 dev->header_ops = ð_header_ops;
365 dev->type = ARPHRD_ETHER;
366 dev->hard_header_len = ETH_HLEN;
367 dev->min_header_len = ETH_HLEN;
368 dev->mtu = ETH_DATA_LEN;
369 dev->min_mtu = ETH_MIN_MTU;
370 dev->max_mtu = ETH_DATA_LEN;
371 dev->addr_len = ETH_ALEN;
372 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
373 dev->flags = IFF_BROADCAST|IFF_MULTICAST;
374 dev->priv_flags |= IFF_TX_SKB_SHARING;
375
376 eth_broadcast_addr(dev->broadcast);
377
378}
379EXPORT_SYMBOL(ether_setup);
380
381/**
382 * alloc_etherdev_mqs - Allocates and sets up an Ethernet device
383 * @sizeof_priv: Size of additional driver-private structure to be allocated
384 * for this Ethernet device
385 * @txqs: The number of TX queues this device has.
386 * @rxqs: The number of RX queues this device has.
387 *
388 * Fill in the fields of the device structure with Ethernet-generic
389 * values. Basically does everything except registering the device.
390 *
391 * Constructs a new net device, complete with a private data area of
392 * size (sizeof_priv). A 32-byte (not bit) alignment is enforced for
393 * this private data area.
394 */
395
396struct net_device *alloc_etherdev_mqs(int sizeof_priv, unsigned int txqs,
397 unsigned int rxqs)
398{
399 return alloc_netdev_mqs(sizeof_priv, "eth%d", NET_NAME_UNKNOWN,
400 ether_setup, txqs, rxqs);
401}
402EXPORT_SYMBOL(alloc_etherdev_mqs);
403
404ssize_t sysfs_format_mac(char *buf, const unsigned char *addr, int len)
405{
406 return scnprintf(buf, PAGE_SIZE, "%*phC\n", len, addr);
407}
408EXPORT_SYMBOL(sysfs_format_mac);
409
410struct sk_buff *eth_gro_receive(struct list_head *head, struct sk_buff *skb)
411{
412 const struct packet_offload *ptype;
413 unsigned int hlen, off_eth;
414 struct sk_buff *pp = NULL;
415 struct ethhdr *eh, *eh2;
416 struct sk_buff *p;
417 __be16 type;
418 int flush = 1;
419
420 off_eth = skb_gro_offset(skb);
421 hlen = off_eth + sizeof(*eh);
422 eh = skb_gro_header_fast(skb, off_eth);
423 if (skb_gro_header_hard(skb, hlen)) {
424 eh = skb_gro_header_slow(skb, hlen, off_eth);
425 if (unlikely(!eh))
426 goto out;
427 }
428
429 flush = 0;
430
431 list_for_each_entry(p, head, list) {
432 if (!NAPI_GRO_CB(p)->same_flow)
433 continue;
434
435 eh2 = (struct ethhdr *)(p->data + off_eth);
436 if (compare_ether_header(eh, eh2)) {
437 NAPI_GRO_CB(p)->same_flow = 0;
438 continue;
439 }
440 }
441
442 type = eh->h_proto;
443
444 rcu_read_lock();
445 ptype = gro_find_receive_by_type(type);
446 if (ptype == NULL) {
447 flush = 1;
448 goto out_unlock;
449 }
450
451 skb_gro_pull(skb, sizeof(*eh));
452 skb_gro_postpull_rcsum(skb, eh, sizeof(*eh));
453
454 pp = indirect_call_gro_receive_inet(ptype->callbacks.gro_receive,
455 ipv6_gro_receive, inet_gro_receive,
456 head, skb);
457
458out_unlock:
459 rcu_read_unlock();
460out:
461 skb_gro_flush_final(skb, pp, flush);
462
463 return pp;
464}
465EXPORT_SYMBOL(eth_gro_receive);
466
467int eth_gro_complete(struct sk_buff *skb, int nhoff)
468{
469 struct ethhdr *eh = (struct ethhdr *)(skb->data + nhoff);
470 __be16 type = eh->h_proto;
471 struct packet_offload *ptype;
472 int err = -ENOSYS;
473
474 if (skb->encapsulation)
475 skb_set_inner_mac_header(skb, nhoff);
476
477 rcu_read_lock();
478 ptype = gro_find_complete_by_type(type);
479 if (ptype != NULL)
480 err = INDIRECT_CALL_INET(ptype->callbacks.gro_complete,
481 ipv6_gro_complete, inet_gro_complete,
482 skb, nhoff + sizeof(*eh));
483
484 rcu_read_unlock();
485 return err;
486}
487EXPORT_SYMBOL(eth_gro_complete);
488
489static struct packet_offload eth_packet_offload __read_mostly = {
490 .type = cpu_to_be16(ETH_P_TEB),
491 .priority = 10,
492 .callbacks = {
493 .gro_receive = eth_gro_receive,
494 .gro_complete = eth_gro_complete,
495 },
496};
497
498static int __init eth_offload_init(void)
499{
500 dev_add_offload(ð_packet_offload);
501
502 return 0;
503}
504
505fs_initcall(eth_offload_init);
506
507unsigned char * __weak arch_get_platform_mac_address(void)
508{
509 return NULL;
510}
511
512int eth_platform_get_mac_address(struct device *dev, u8 *mac_addr)
513{
514 unsigned char *addr;
515 int ret;
516
517 ret = of_get_mac_address(dev->of_node, mac_addr);
518 if (!ret)
519 return 0;
520
521 addr = arch_get_platform_mac_address();
522 if (!addr)
523 return -ENODEV;
524
525 ether_addr_copy(mac_addr, addr);
526
527 return 0;
528}
529EXPORT_SYMBOL(eth_platform_get_mac_address);
530
531/**
532 * nvmem_get_mac_address - Obtain the MAC address from an nvmem cell named
533 * 'mac-address' associated with given device.
534 *
535 * @dev: Device with which the mac-address cell is associated.
536 * @addrbuf: Buffer to which the MAC address will be copied on success.
537 *
538 * Returns 0 on success or a negative error number on failure.
539 */
540int nvmem_get_mac_address(struct device *dev, void *addrbuf)
541{
542 struct nvmem_cell *cell;
543 const void *mac;
544 size_t len;
545
546 cell = nvmem_cell_get(dev, "mac-address");
547 if (IS_ERR(cell))
548 return PTR_ERR(cell);
549
550 mac = nvmem_cell_read(cell, &len);
551 nvmem_cell_put(cell);
552
553 if (IS_ERR(mac))
554 return PTR_ERR(mac);
555
556 if (len != ETH_ALEN || !is_valid_ether_addr(mac)) {
557 kfree(mac);
558 return -EINVAL;
559 }
560
561 ether_addr_copy(addrbuf, mac);
562 kfree(mac);
563
564 return 0;
565}
566EXPORT_SYMBOL(nvmem_get_mac_address);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * Ethernet-type device handling.
8 *
9 * Version: @(#)eth.c 1.0.7 05/25/93
10 *
11 * Authors: Ross Biro
12 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
13 * Mark Evans, <evansmp@uhura.aston.ac.uk>
14 * Florian La Roche, <rzsfl@rz.uni-sb.de>
15 * Alan Cox, <gw4pts@gw4pts.ampr.org>
16 *
17 * Fixes:
18 * Mr Linux : Arp problems
19 * Alan Cox : Generic queue tidyup (very tiny here)
20 * Alan Cox : eth_header ntohs should be htons
21 * Alan Cox : eth_rebuild_header missing an htons and
22 * minor other things.
23 * Tegge : Arp bug fixes.
24 * Florian : Removed many unnecessary functions, code cleanup
25 * and changes for new arp and skbuff.
26 * Alan Cox : Redid header building to reflect new format.
27 * Alan Cox : ARP only when compiled with CONFIG_INET
28 * Greg Page : 802.2 and SNAP stuff.
29 * Alan Cox : MAC layer pointers/new format.
30 * Paul Gortmaker : eth_copy_and_sum shouldn't csum padding.
31 * Alan Cox : Protect against forwarding explosions with
32 * older network drivers and IFF_ALLMULTI.
33 * Christer Weinigel : Better rebuild header message.
34 * Andrew Morton : 26Feb01: kill ether_setup() - use netdev_boot_setup().
35 */
36#include <linux/module.h>
37#include <linux/types.h>
38#include <linux/kernel.h>
39#include <linux/string.h>
40#include <linux/mm.h>
41#include <linux/socket.h>
42#include <linux/in.h>
43#include <linux/inet.h>
44#include <linux/ip.h>
45#include <linux/netdevice.h>
46#include <linux/nvmem-consumer.h>
47#include <linux/etherdevice.h>
48#include <linux/skbuff.h>
49#include <linux/errno.h>
50#include <linux/init.h>
51#include <linux/if_ether.h>
52#include <linux/of_net.h>
53#include <linux/pci.h>
54#include <linux/property.h>
55#include <net/dst.h>
56#include <net/arp.h>
57#include <net/sock.h>
58#include <net/ipv6.h>
59#include <net/ip.h>
60#include <net/dsa.h>
61#include <net/flow_dissector.h>
62#include <net/gro.h>
63#include <linux/uaccess.h>
64#include <net/pkt_sched.h>
65
66/**
67 * eth_header - create the Ethernet header
68 * @skb: buffer to alter
69 * @dev: source device
70 * @type: Ethernet type field
71 * @daddr: destination address (NULL leave destination address)
72 * @saddr: source address (NULL use device source address)
73 * @len: packet length (<= skb->len)
74 *
75 *
76 * Set the protocol type. For a packet of type ETH_P_802_3/2 we put the length
77 * in here instead.
78 */
79int eth_header(struct sk_buff *skb, struct net_device *dev,
80 unsigned short type,
81 const void *daddr, const void *saddr, unsigned int len)
82{
83 struct ethhdr *eth = skb_push(skb, ETH_HLEN);
84
85 if (type != ETH_P_802_3 && type != ETH_P_802_2)
86 eth->h_proto = htons(type);
87 else
88 eth->h_proto = htons(len);
89
90 /*
91 * Set the source hardware address.
92 */
93
94 if (!saddr)
95 saddr = dev->dev_addr;
96 memcpy(eth->h_source, saddr, ETH_ALEN);
97
98 if (daddr) {
99 memcpy(eth->h_dest, daddr, ETH_ALEN);
100 return ETH_HLEN;
101 }
102
103 /*
104 * Anyway, the loopback-device should never use this function...
105 */
106
107 if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) {
108 eth_zero_addr(eth->h_dest);
109 return ETH_HLEN;
110 }
111
112 return -ETH_HLEN;
113}
114EXPORT_SYMBOL(eth_header);
115
116/**
117 * eth_get_headlen - determine the length of header for an ethernet frame
118 * @dev: pointer to network device
119 * @data: pointer to start of frame
120 * @len: total length of frame
121 *
122 * Make a best effort attempt to pull the length for all of the headers for
123 * a given frame in a linear buffer.
124 */
125u32 eth_get_headlen(const struct net_device *dev, const void *data, u32 len)
126{
127 const unsigned int flags = FLOW_DISSECTOR_F_PARSE_1ST_FRAG;
128 const struct ethhdr *eth = (const struct ethhdr *)data;
129 struct flow_keys_basic keys;
130
131 /* this should never happen, but better safe than sorry */
132 if (unlikely(len < sizeof(*eth)))
133 return len;
134
135 /* parse any remaining L2/L3 headers, check for L4 */
136 if (!skb_flow_dissect_flow_keys_basic(dev_net(dev), NULL, &keys, data,
137 eth->h_proto, sizeof(*eth),
138 len, flags))
139 return max_t(u32, keys.control.thoff, sizeof(*eth));
140
141 /* parse for any L4 headers */
142 return min_t(u32, __skb_get_poff(NULL, data, &keys, len), len);
143}
144EXPORT_SYMBOL(eth_get_headlen);
145
146/**
147 * eth_type_trans - determine the packet's protocol ID.
148 * @skb: received socket data
149 * @dev: receiving network device
150 *
151 * The rule here is that we
152 * assume 802.3 if the type field is short enough to be a length.
153 * This is normal practice and works for any 'now in use' protocol.
154 */
155__be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev)
156{
157 unsigned short _service_access_point;
158 const unsigned short *sap;
159 const struct ethhdr *eth;
160
161 skb->dev = dev;
162 skb_reset_mac_header(skb);
163
164 eth = (struct ethhdr *)skb->data;
165 skb_pull_inline(skb, ETH_HLEN);
166
167 if (unlikely(!ether_addr_equal_64bits(eth->h_dest,
168 dev->dev_addr))) {
169 if (unlikely(is_multicast_ether_addr_64bits(eth->h_dest))) {
170 if (ether_addr_equal_64bits(eth->h_dest, dev->broadcast))
171 skb->pkt_type = PACKET_BROADCAST;
172 else
173 skb->pkt_type = PACKET_MULTICAST;
174 } else {
175 skb->pkt_type = PACKET_OTHERHOST;
176 }
177 }
178
179 /*
180 * Some variants of DSA tagging don't have an ethertype field
181 * at all, so we check here whether one of those tagging
182 * variants has been configured on the receiving interface,
183 * and if so, set skb->protocol without looking at the packet.
184 */
185 if (unlikely(netdev_uses_dsa(dev)))
186 return htons(ETH_P_XDSA);
187
188 if (likely(eth_proto_is_802_3(eth->h_proto)))
189 return eth->h_proto;
190
191 /*
192 * This is a magic hack to spot IPX packets. Older Novell breaks
193 * the protocol design and runs IPX over 802.3 without an 802.2 LLC
194 * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
195 * won't work for fault tolerant netware but does for the rest.
196 */
197 sap = skb_header_pointer(skb, 0, sizeof(*sap), &_service_access_point);
198 if (sap && *sap == 0xFFFF)
199 return htons(ETH_P_802_3);
200
201 /*
202 * Real 802.2 LLC
203 */
204 return htons(ETH_P_802_2);
205}
206EXPORT_SYMBOL(eth_type_trans);
207
208/**
209 * eth_header_parse - extract hardware address from packet
210 * @skb: packet to extract header from
211 * @haddr: destination buffer
212 */
213int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr)
214{
215 const struct ethhdr *eth = eth_hdr(skb);
216 memcpy(haddr, eth->h_source, ETH_ALEN);
217 return ETH_ALEN;
218}
219EXPORT_SYMBOL(eth_header_parse);
220
221/**
222 * eth_header_cache - fill cache entry from neighbour
223 * @neigh: source neighbour
224 * @hh: destination cache entry
225 * @type: Ethernet type field
226 *
227 * Create an Ethernet header template from the neighbour.
228 */
229int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh, __be16 type)
230{
231 struct ethhdr *eth;
232 const struct net_device *dev = neigh->dev;
233
234 eth = (struct ethhdr *)
235 (((u8 *) hh->hh_data) + (HH_DATA_OFF(sizeof(*eth))));
236
237 if (type == htons(ETH_P_802_3))
238 return -1;
239
240 eth->h_proto = type;
241 memcpy(eth->h_source, dev->dev_addr, ETH_ALEN);
242 memcpy(eth->h_dest, neigh->ha, ETH_ALEN);
243
244 /* Pairs with READ_ONCE() in neigh_resolve_output(),
245 * neigh_hh_output() and neigh_update_hhs().
246 */
247 smp_store_release(&hh->hh_len, ETH_HLEN);
248
249 return 0;
250}
251EXPORT_SYMBOL(eth_header_cache);
252
253/**
254 * eth_header_cache_update - update cache entry
255 * @hh: destination cache entry
256 * @dev: network device
257 * @haddr: new hardware address
258 *
259 * Called by Address Resolution module to notify changes in address.
260 */
261void eth_header_cache_update(struct hh_cache *hh,
262 const struct net_device *dev,
263 const unsigned char *haddr)
264{
265 memcpy(((u8 *) hh->hh_data) + HH_DATA_OFF(sizeof(struct ethhdr)),
266 haddr, ETH_ALEN);
267}
268EXPORT_SYMBOL(eth_header_cache_update);
269
270/**
271 * eth_header_parse_protocol - extract protocol from L2 header
272 * @skb: packet to extract protocol from
273 */
274__be16 eth_header_parse_protocol(const struct sk_buff *skb)
275{
276 const struct ethhdr *eth = eth_hdr(skb);
277
278 return eth->h_proto;
279}
280EXPORT_SYMBOL(eth_header_parse_protocol);
281
282/**
283 * eth_prepare_mac_addr_change - prepare for mac change
284 * @dev: network device
285 * @p: socket address
286 */
287int eth_prepare_mac_addr_change(struct net_device *dev, void *p)
288{
289 struct sockaddr *addr = p;
290
291 if (!(dev->priv_flags & IFF_LIVE_ADDR_CHANGE) && netif_running(dev))
292 return -EBUSY;
293 if (!is_valid_ether_addr(addr->sa_data))
294 return -EADDRNOTAVAIL;
295 return 0;
296}
297EXPORT_SYMBOL(eth_prepare_mac_addr_change);
298
299/**
300 * eth_commit_mac_addr_change - commit mac change
301 * @dev: network device
302 * @p: socket address
303 */
304void eth_commit_mac_addr_change(struct net_device *dev, void *p)
305{
306 struct sockaddr *addr = p;
307
308 eth_hw_addr_set(dev, addr->sa_data);
309}
310EXPORT_SYMBOL(eth_commit_mac_addr_change);
311
312/**
313 * eth_mac_addr - set new Ethernet hardware address
314 * @dev: network device
315 * @p: socket address
316 *
317 * Change hardware address of device.
318 *
319 * This doesn't change hardware matching, so needs to be overridden
320 * for most real devices.
321 */
322int eth_mac_addr(struct net_device *dev, void *p)
323{
324 int ret;
325
326 ret = eth_prepare_mac_addr_change(dev, p);
327 if (ret < 0)
328 return ret;
329 eth_commit_mac_addr_change(dev, p);
330 return 0;
331}
332EXPORT_SYMBOL(eth_mac_addr);
333
334int eth_validate_addr(struct net_device *dev)
335{
336 if (!is_valid_ether_addr(dev->dev_addr))
337 return -EADDRNOTAVAIL;
338
339 return 0;
340}
341EXPORT_SYMBOL(eth_validate_addr);
342
343const struct header_ops eth_header_ops ____cacheline_aligned = {
344 .create = eth_header,
345 .parse = eth_header_parse,
346 .cache = eth_header_cache,
347 .cache_update = eth_header_cache_update,
348 .parse_protocol = eth_header_parse_protocol,
349};
350
351/**
352 * ether_setup - setup Ethernet network device
353 * @dev: network device
354 *
355 * Fill in the fields of the device structure with Ethernet-generic values.
356 */
357void ether_setup(struct net_device *dev)
358{
359 dev->header_ops = ð_header_ops;
360 dev->type = ARPHRD_ETHER;
361 dev->hard_header_len = ETH_HLEN;
362 dev->min_header_len = ETH_HLEN;
363 dev->mtu = ETH_DATA_LEN;
364 dev->min_mtu = ETH_MIN_MTU;
365 dev->max_mtu = ETH_DATA_LEN;
366 dev->addr_len = ETH_ALEN;
367 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
368 dev->flags = IFF_BROADCAST|IFF_MULTICAST;
369 dev->priv_flags |= IFF_TX_SKB_SHARING;
370
371 eth_broadcast_addr(dev->broadcast);
372
373}
374EXPORT_SYMBOL(ether_setup);
375
376/**
377 * alloc_etherdev_mqs - Allocates and sets up an Ethernet device
378 * @sizeof_priv: Size of additional driver-private structure to be allocated
379 * for this Ethernet device
380 * @txqs: The number of TX queues this device has.
381 * @rxqs: The number of RX queues this device has.
382 *
383 * Fill in the fields of the device structure with Ethernet-generic
384 * values. Basically does everything except registering the device.
385 *
386 * Constructs a new net device, complete with a private data area of
387 * size (sizeof_priv). A 32-byte (not bit) alignment is enforced for
388 * this private data area.
389 */
390
391struct net_device *alloc_etherdev_mqs(int sizeof_priv, unsigned int txqs,
392 unsigned int rxqs)
393{
394 return alloc_netdev_mqs(sizeof_priv, "eth%d", NET_NAME_ENUM,
395 ether_setup, txqs, rxqs);
396}
397EXPORT_SYMBOL(alloc_etherdev_mqs);
398
399ssize_t sysfs_format_mac(char *buf, const unsigned char *addr, int len)
400{
401 return sysfs_emit(buf, "%*phC\n", len, addr);
402}
403EXPORT_SYMBOL(sysfs_format_mac);
404
405struct sk_buff *eth_gro_receive(struct list_head *head, struct sk_buff *skb)
406{
407 const struct packet_offload *ptype;
408 unsigned int hlen, off_eth;
409 struct sk_buff *pp = NULL;
410 struct ethhdr *eh, *eh2;
411 struct sk_buff *p;
412 __be16 type;
413 int flush = 1;
414
415 off_eth = skb_gro_offset(skb);
416 hlen = off_eth + sizeof(*eh);
417 eh = skb_gro_header(skb, hlen, off_eth);
418 if (unlikely(!eh))
419 goto out;
420
421 flush = 0;
422
423 list_for_each_entry(p, head, list) {
424 if (!NAPI_GRO_CB(p)->same_flow)
425 continue;
426
427 eh2 = (struct ethhdr *)(p->data + off_eth);
428 if (compare_ether_header(eh, eh2)) {
429 NAPI_GRO_CB(p)->same_flow = 0;
430 continue;
431 }
432 }
433
434 type = eh->h_proto;
435
436 ptype = gro_find_receive_by_type(type);
437 if (ptype == NULL) {
438 flush = 1;
439 goto out;
440 }
441
442 skb_gro_pull(skb, sizeof(*eh));
443 skb_gro_postpull_rcsum(skb, eh, sizeof(*eh));
444
445 pp = indirect_call_gro_receive_inet(ptype->callbacks.gro_receive,
446 ipv6_gro_receive, inet_gro_receive,
447 head, skb);
448
449out:
450 skb_gro_flush_final(skb, pp, flush);
451
452 return pp;
453}
454EXPORT_SYMBOL(eth_gro_receive);
455
456int eth_gro_complete(struct sk_buff *skb, int nhoff)
457{
458 struct ethhdr *eh = (struct ethhdr *)(skb->data + nhoff);
459 __be16 type = eh->h_proto;
460 struct packet_offload *ptype;
461 int err = -ENOSYS;
462
463 if (skb->encapsulation)
464 skb_set_inner_mac_header(skb, nhoff);
465
466 ptype = gro_find_complete_by_type(type);
467 if (ptype != NULL)
468 err = INDIRECT_CALL_INET(ptype->callbacks.gro_complete,
469 ipv6_gro_complete, inet_gro_complete,
470 skb, nhoff + sizeof(*eh));
471
472 return err;
473}
474EXPORT_SYMBOL(eth_gro_complete);
475
476static struct packet_offload eth_packet_offload __read_mostly = {
477 .type = cpu_to_be16(ETH_P_TEB),
478 .priority = 10,
479 .callbacks = {
480 .gro_receive = eth_gro_receive,
481 .gro_complete = eth_gro_complete,
482 },
483};
484
485static int __init eth_offload_init(void)
486{
487 dev_add_offload(ð_packet_offload);
488
489 return 0;
490}
491
492fs_initcall(eth_offload_init);
493
494unsigned char * __weak arch_get_platform_mac_address(void)
495{
496 return NULL;
497}
498
499int eth_platform_get_mac_address(struct device *dev, u8 *mac_addr)
500{
501 unsigned char *addr;
502 int ret;
503
504 ret = of_get_mac_address(dev->of_node, mac_addr);
505 if (!ret)
506 return 0;
507
508 addr = arch_get_platform_mac_address();
509 if (!addr)
510 return -ENODEV;
511
512 ether_addr_copy(mac_addr, addr);
513
514 return 0;
515}
516EXPORT_SYMBOL(eth_platform_get_mac_address);
517
518/**
519 * platform_get_ethdev_address - Set netdev's MAC address from a given device
520 * @dev: Pointer to the device
521 * @netdev: Pointer to netdev to write the address to
522 *
523 * Wrapper around eth_platform_get_mac_address() which writes the address
524 * directly to netdev->dev_addr.
525 */
526int platform_get_ethdev_address(struct device *dev, struct net_device *netdev)
527{
528 u8 addr[ETH_ALEN] __aligned(2);
529 int ret;
530
531 ret = eth_platform_get_mac_address(dev, addr);
532 if (!ret)
533 eth_hw_addr_set(netdev, addr);
534 return ret;
535}
536EXPORT_SYMBOL(platform_get_ethdev_address);
537
538/**
539 * nvmem_get_mac_address - Obtain the MAC address from an nvmem cell named
540 * 'mac-address' associated with given device.
541 *
542 * @dev: Device with which the mac-address cell is associated.
543 * @addrbuf: Buffer to which the MAC address will be copied on success.
544 *
545 * Returns 0 on success or a negative error number on failure.
546 */
547int nvmem_get_mac_address(struct device *dev, void *addrbuf)
548{
549 struct nvmem_cell *cell;
550 const void *mac;
551 size_t len;
552
553 cell = nvmem_cell_get(dev, "mac-address");
554 if (IS_ERR(cell))
555 return PTR_ERR(cell);
556
557 mac = nvmem_cell_read(cell, &len);
558 nvmem_cell_put(cell);
559
560 if (IS_ERR(mac))
561 return PTR_ERR(mac);
562
563 if (len != ETH_ALEN || !is_valid_ether_addr(mac)) {
564 kfree(mac);
565 return -EINVAL;
566 }
567
568 ether_addr_copy(addrbuf, mac);
569 kfree(mac);
570
571 return 0;
572}
573
574static int fwnode_get_mac_addr(struct fwnode_handle *fwnode,
575 const char *name, char *addr)
576{
577 int ret;
578
579 ret = fwnode_property_read_u8_array(fwnode, name, addr, ETH_ALEN);
580 if (ret)
581 return ret;
582
583 if (!is_valid_ether_addr(addr))
584 return -EINVAL;
585 return 0;
586}
587
588/**
589 * fwnode_get_mac_address - Get the MAC from the firmware node
590 * @fwnode: Pointer to the firmware node
591 * @addr: Address of buffer to store the MAC in
592 *
593 * Search the firmware node for the best MAC address to use. 'mac-address' is
594 * checked first, because that is supposed to contain to "most recent" MAC
595 * address. If that isn't set, then 'local-mac-address' is checked next,
596 * because that is the default address. If that isn't set, then the obsolete
597 * 'address' is checked, just in case we're using an old device tree.
598 *
599 * Note that the 'address' property is supposed to contain a virtual address of
600 * the register set, but some DTS files have redefined that property to be the
601 * MAC address.
602 *
603 * All-zero MAC addresses are rejected, because those could be properties that
604 * exist in the firmware tables, but were not updated by the firmware. For
605 * example, the DTS could define 'mac-address' and 'local-mac-address', with
606 * zero MAC addresses. Some older U-Boots only initialized 'local-mac-address'.
607 * In this case, the real MAC is in 'local-mac-address', and 'mac-address'
608 * exists but is all zeros.
609 */
610int fwnode_get_mac_address(struct fwnode_handle *fwnode, char *addr)
611{
612 if (!fwnode_get_mac_addr(fwnode, "mac-address", addr) ||
613 !fwnode_get_mac_addr(fwnode, "local-mac-address", addr) ||
614 !fwnode_get_mac_addr(fwnode, "address", addr))
615 return 0;
616
617 return -ENOENT;
618}
619EXPORT_SYMBOL(fwnode_get_mac_address);
620
621/**
622 * device_get_mac_address - Get the MAC for a given device
623 * @dev: Pointer to the device
624 * @addr: Address of buffer to store the MAC in
625 */
626int device_get_mac_address(struct device *dev, char *addr)
627{
628 return fwnode_get_mac_address(dev_fwnode(dev), addr);
629}
630EXPORT_SYMBOL(device_get_mac_address);
631
632/**
633 * device_get_ethdev_address - Set netdev's MAC address from a given device
634 * @dev: Pointer to the device
635 * @netdev: Pointer to netdev to write the address to
636 *
637 * Wrapper around device_get_mac_address() which writes the address
638 * directly to netdev->dev_addr.
639 */
640int device_get_ethdev_address(struct device *dev, struct net_device *netdev)
641{
642 u8 addr[ETH_ALEN];
643 int ret;
644
645 ret = device_get_mac_address(dev, addr);
646 if (!ret)
647 eth_hw_addr_set(netdev, addr);
648 return ret;
649}
650EXPORT_SYMBOL(device_get_ethdev_address);