Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
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. | |
5 | * | |
6 | * Ethernet-type device handling. | |
7 | * | |
8 | * Version: @(#)eth.c 1.0.7 05/25/93 | |
9 | * | |
02c30a84 | 10 | * Authors: Ross Biro |
1da177e4 LT |
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> | |
03d52d7c | 15 | * |
1da177e4 LT |
16 | * Fixes: |
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 | |
21 | * minor other things. | |
03d52d7c | 22 | * Tegge : Arp bug fixes. |
1da177e4 LT |
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(). | |
34 | * | |
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. | |
39 | */ | |
40 | #include <linux/module.h> | |
41 | #include <linux/types.h> | |
42 | #include <linux/kernel.h> | |
1da177e4 LT |
43 | #include <linux/string.h> |
44 | #include <linux/mm.h> | |
45 | #include <linux/socket.h> | |
46 | #include <linux/in.h> | |
47 | #include <linux/inet.h> | |
48 | #include <linux/ip.h> | |
49 | #include <linux/netdevice.h> | |
50 | #include <linux/etherdevice.h> | |
51 | #include <linux/skbuff.h> | |
52 | #include <linux/errno.h> | |
1da177e4 | 53 | #include <linux/init.h> |
46f25dff | 54 | #include <linux/if_ether.h> |
1da177e4 LT |
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> | |
cf85d08f | 60 | #include <net/dsa.h> |
10b89ee4 | 61 | #include <net/flow_dissector.h> |
118a7b0e | 62 | #include <linux/uaccess.h> |
1da177e4 | 63 | |
1da177e4 LT |
64 | __setup("ether=", netdev_boot_setup); |
65 | ||
d3e01f71 SH |
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) | |
1da177e4 | 74 | * |
d3e01f71 | 75 | * |
bf9ae538 OP |
76 | * Set the protocol type. For a packet of type ETH_P_802_3/2 we put the length |
77 | * in here instead. | |
1da177e4 | 78 | */ |
3b04ddde SH |
79 | int eth_header(struct sk_buff *skb, struct net_device *dev, |
80 | unsigned short type, | |
95c96174 | 81 | const void *daddr, const void *saddr, unsigned int len) |
1da177e4 | 82 | { |
2e4ca75b | 83 | struct ethhdr *eth = (struct ethhdr *)skb_push(skb, ETH_HLEN); |
1da177e4 | 84 | |
bf9ae538 | 85 | if (type != ETH_P_802_3 && type != ETH_P_802_2) |
1da177e4 LT |
86 | eth->h_proto = htons(type); |
87 | else | |
88 | eth->h_proto = htons(len); | |
89 | ||
90 | /* | |
2e4ca75b | 91 | * Set the source hardware address. |
1da177e4 | 92 | */ |
2e4ca75b SH |
93 | |
94 | if (!saddr) | |
ff593c59 | 95 | saddr = dev->dev_addr; |
23f1f4ef | 96 | memcpy(eth->h_source, saddr, ETH_ALEN); |
1da177e4 | 97 | |
2e4ca75b | 98 | if (daddr) { |
23f1f4ef | 99 | memcpy(eth->h_dest, daddr, ETH_ALEN); |
f8d0e3f1 JHS |
100 | return ETH_HLEN; |
101 | } | |
2e4ca75b | 102 | |
1da177e4 | 103 | /* |
2e4ca75b | 104 | * Anyway, the loopback-device should never use this function... |
1da177e4 LT |
105 | */ |
106 | ||
2e4ca75b | 107 | if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) { |
afc130dd | 108 | eth_zero_addr(eth->h_dest); |
1da177e4 LT |
109 | return ETH_HLEN; |
110 | } | |
2e4ca75b | 111 | |
1da177e4 LT |
112 | return -ETH_HLEN; |
113 | } | |
3b04ddde | 114 | EXPORT_SYMBOL(eth_header); |
1da177e4 | 115 | |
56193d1b | 116 | /** |
ecea4991 | 117 | * eth_get_headlen - determine the length of header for an ethernet frame |
56193d1b AD |
118 | * @data: pointer to start of frame |
119 | * @len: total length of frame | |
120 | * | |
121 | * Make a best effort attempt to pull the length for all of the headers for | |
122 | * a given frame in a linear buffer. | |
123 | */ | |
124 | u32 eth_get_headlen(void *data, unsigned int len) | |
125 | { | |
126 | const struct ethhdr *eth = (const struct ethhdr *)data; | |
127 | struct flow_keys keys; | |
128 | ||
129 | /* this should never happen, but better safe than sorry */ | |
130 | if (len < sizeof(*eth)) | |
131 | return len; | |
132 | ||
133 | /* parse any remaining L2/L3 headers, check for L4 */ | |
06635a35 | 134 | if (!skb_flow_dissect_flow_keys_buf(&keys, data, eth->h_proto, |
cd79a238 | 135 | sizeof(*eth), len, 0)) |
c3f83241 | 136 | return max_t(u32, keys.control.thoff, sizeof(*eth)); |
56193d1b AD |
137 | |
138 | /* parse for any L4 headers */ | |
139 | return min_t(u32, __skb_get_poff(NULL, data, &keys, len), len); | |
140 | } | |
141 | EXPORT_SYMBOL(eth_get_headlen); | |
142 | ||
d3e01f71 SH |
143 | /** |
144 | * eth_type_trans - determine the packet's protocol ID. | |
145 | * @skb: received socket data | |
146 | * @dev: receiving network device | |
147 | * | |
148 | * The rule here is that we | |
149 | * assume 802.3 if the type field is short enough to be a length. | |
150 | * This is normal practice and works for any 'now in use' protocol. | |
1da177e4 | 151 | */ |
ab611487 | 152 | __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev) |
1da177e4 | 153 | { |
0864c158 ED |
154 | unsigned short _service_access_point; |
155 | const unsigned short *sap; | |
156 | const struct ethhdr *eth; | |
2e4ca75b | 157 | |
4c13eb66 | 158 | skb->dev = dev; |
459a98ed | 159 | skb_reset_mac_header(skb); |
610986e7 AD |
160 | |
161 | eth = (struct ethhdr *)skb->data; | |
47d29646 | 162 | skb_pull_inline(skb, ETH_HLEN); |
2e4ca75b | 163 | |
d54385ce | 164 | if (unlikely(is_multicast_ether_addr_64bits(eth->h_dest))) { |
a6700db1 | 165 | if (ether_addr_equal_64bits(eth->h_dest, dev->broadcast)) |
ba645c16 | 166 | skb->pkt_type = PACKET_BROADCAST; |
1da177e4 | 167 | else |
ba645c16 | 168 | skb->pkt_type = PACKET_MULTICAST; |
1da177e4 | 169 | } |
12861b7b | 170 | else if (unlikely(!ether_addr_equal_64bits(eth->h_dest, |
171 | dev->dev_addr))) | |
172 | skb->pkt_type = PACKET_OTHERHOST; | |
2e4ca75b | 173 | |
cf85d08f LB |
174 | /* |
175 | * Some variants of DSA tagging don't have an ethertype field | |
176 | * at all, so we check here whether one of those tagging | |
177 | * variants has been configured on the receiving interface, | |
178 | * and if so, set skb->protocol without looking at the packet. | |
179 | */ | |
3e8a72d1 FF |
180 | if (unlikely(netdev_uses_dsa(dev))) |
181 | return htons(ETH_P_XDSA); | |
cf85d08f | 182 | |
2c7a88c2 | 183 | if (likely(eth_proto_is_802_3(eth->h_proto))) |
1da177e4 | 184 | return eth->h_proto; |
2e4ca75b | 185 | |
1da177e4 | 186 | /* |
2e4ca75b SH |
187 | * This is a magic hack to spot IPX packets. Older Novell breaks |
188 | * the protocol design and runs IPX over 802.3 without an 802.2 LLC | |
189 | * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This | |
190 | * won't work for fault tolerant netware but does for the rest. | |
1da177e4 | 191 | */ |
0864c158 ED |
192 | sap = skb_header_pointer(skb, 0, sizeof(*sap), &_service_access_point); |
193 | if (sap && *sap == 0xFFFF) | |
1da177e4 | 194 | return htons(ETH_P_802_3); |
2e4ca75b | 195 | |
1da177e4 | 196 | /* |
2e4ca75b | 197 | * Real 802.2 LLC |
1da177e4 LT |
198 | */ |
199 | return htons(ETH_P_802_2); | |
200 | } | |
2e4ca75b | 201 | EXPORT_SYMBOL(eth_type_trans); |
1da177e4 | 202 | |
d3e01f71 SH |
203 | /** |
204 | * eth_header_parse - extract hardware address from packet | |
205 | * @skb: packet to extract header from | |
206 | * @haddr: destination buffer | |
207 | */ | |
3b04ddde | 208 | int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr) |
1da177e4 | 209 | { |
b95cce35 | 210 | const struct ethhdr *eth = eth_hdr(skb); |
1da177e4 LT |
211 | memcpy(haddr, eth->h_source, ETH_ALEN); |
212 | return ETH_ALEN; | |
213 | } | |
3b04ddde | 214 | EXPORT_SYMBOL(eth_header_parse); |
1da177e4 | 215 | |
d3e01f71 SH |
216 | /** |
217 | * eth_header_cache - fill cache entry from neighbour | |
218 | * @neigh: source neighbour | |
219 | * @hh: destination cache entry | |
48daec03 | 220 | * @type: Ethernet type field |
2c53040f | 221 | * |
d3e01f71 SH |
222 | * Create an Ethernet header template from the neighbour. |
223 | */ | |
e69dd336 | 224 | int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh, __be16 type) |
1da177e4 | 225 | { |
1da177e4 | 226 | struct ethhdr *eth; |
3b04ddde | 227 | const struct net_device *dev = neigh->dev; |
1da177e4 | 228 | |
2e4ca75b SH |
229 | eth = (struct ethhdr *) |
230 | (((u8 *) hh->hh_data) + (HH_DATA_OFF(sizeof(*eth)))); | |
1da177e4 | 231 | |
f576e24f | 232 | if (type == htons(ETH_P_802_3)) |
1da177e4 LT |
233 | return -1; |
234 | ||
235 | eth->h_proto = type; | |
23f1f4ef SH |
236 | memcpy(eth->h_source, dev->dev_addr, ETH_ALEN); |
237 | memcpy(eth->h_dest, neigh->ha, ETH_ALEN); | |
1da177e4 LT |
238 | hh->hh_len = ETH_HLEN; |
239 | return 0; | |
240 | } | |
3b04ddde | 241 | EXPORT_SYMBOL(eth_header_cache); |
1da177e4 | 242 | |
d3e01f71 SH |
243 | /** |
244 | * eth_header_cache_update - update cache entry | |
245 | * @hh: destination cache entry | |
246 | * @dev: network device | |
247 | * @haddr: new hardware address | |
248 | * | |
1da177e4 LT |
249 | * Called by Address Resolution module to notify changes in address. |
250 | */ | |
3b04ddde SH |
251 | void eth_header_cache_update(struct hh_cache *hh, |
252 | const struct net_device *dev, | |
253 | const unsigned char *haddr) | |
1da177e4 | 254 | { |
2e4ca75b | 255 | memcpy(((u8 *) hh->hh_data) + HH_DATA_OFF(sizeof(struct ethhdr)), |
23f1f4ef | 256 | haddr, ETH_ALEN); |
1da177e4 | 257 | } |
3b04ddde | 258 | EXPORT_SYMBOL(eth_header_cache_update); |
1da177e4 | 259 | |
fa0879e3 SH |
260 | /** |
261 | * eth_prepare_mac_addr_change - prepare for mac change | |
262 | * @dev: network device | |
263 | * @p: socket address | |
264 | */ | |
265 | int eth_prepare_mac_addr_change(struct net_device *dev, void *p) | |
266 | { | |
267 | struct sockaddr *addr = p; | |
268 | ||
269 | if (!(dev->priv_flags & IFF_LIVE_ADDR_CHANGE) && netif_running(dev)) | |
270 | return -EBUSY; | |
271 | if (!is_valid_ether_addr(addr->sa_data)) | |
272 | return -EADDRNOTAVAIL; | |
273 | return 0; | |
274 | } | |
275 | EXPORT_SYMBOL(eth_prepare_mac_addr_change); | |
276 | ||
277 | /** | |
278 | * eth_commit_mac_addr_change - commit mac change | |
279 | * @dev: network device | |
280 | * @p: socket address | |
281 | */ | |
282 | void eth_commit_mac_addr_change(struct net_device *dev, void *p) | |
283 | { | |
284 | struct sockaddr *addr = p; | |
285 | ||
286 | memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN); | |
287 | } | |
288 | EXPORT_SYMBOL(eth_commit_mac_addr_change); | |
289 | ||
d3e01f71 SH |
290 | /** |
291 | * eth_mac_addr - set new Ethernet hardware address | |
292 | * @dev: network device | |
293 | * @p: socket address | |
2c53040f | 294 | * |
d3e01f71 SH |
295 | * Change hardware address of device. |
296 | * | |
297 | * This doesn't change hardware matching, so needs to be overridden | |
298 | * for most real devices. | |
299 | */ | |
ccad637b | 300 | int eth_mac_addr(struct net_device *dev, void *p) |
1da177e4 | 301 | { |
fa0879e3 | 302 | int ret; |
71bffe55 | 303 | |
fa0879e3 SH |
304 | ret = eth_prepare_mac_addr_change(dev, p); |
305 | if (ret < 0) | |
306 | return ret; | |
307 | eth_commit_mac_addr_change(dev, p); | |
1da177e4 LT |
308 | return 0; |
309 | } | |
ccad637b | 310 | EXPORT_SYMBOL(eth_mac_addr); |
1da177e4 | 311 | |
d3e01f71 SH |
312 | /** |
313 | * eth_change_mtu - set new MTU size | |
314 | * @dev: network device | |
315 | * @new_mtu: new Maximum Transfer Unit | |
316 | * | |
317 | * Allow changing MTU size. Needs to be overridden for devices | |
318 | * supporting jumbo frames. | |
319 | */ | |
ccad637b | 320 | int eth_change_mtu(struct net_device *dev, int new_mtu) |
1da177e4 | 321 | { |
46f25dff | 322 | if (new_mtu < 68 || new_mtu > ETH_DATA_LEN) |
1da177e4 LT |
323 | return -EINVAL; |
324 | dev->mtu = new_mtu; | |
325 | return 0; | |
326 | } | |
ccad637b | 327 | EXPORT_SYMBOL(eth_change_mtu); |
1da177e4 | 328 | |
ccad637b | 329 | int eth_validate_addr(struct net_device *dev) |
bada339b JG |
330 | { |
331 | if (!is_valid_ether_addr(dev->dev_addr)) | |
2ed9926e | 332 | return -EADDRNOTAVAIL; |
bada339b JG |
333 | |
334 | return 0; | |
335 | } | |
ccad637b | 336 | EXPORT_SYMBOL(eth_validate_addr); |
bada339b | 337 | |
3b04ddde SH |
338 | const struct header_ops eth_header_ops ____cacheline_aligned = { |
339 | .create = eth_header, | |
340 | .parse = eth_header_parse, | |
3b04ddde SH |
341 | .cache = eth_header_cache, |
342 | .cache_update = eth_header_cache_update, | |
343 | }; | |
344 | ||
d3e01f71 SH |
345 | /** |
346 | * ether_setup - setup Ethernet network device | |
347 | * @dev: network device | |
2c53040f | 348 | * |
d3e01f71 | 349 | * Fill in the fields of the device structure with Ethernet-generic values. |
1da177e4 LT |
350 | */ |
351 | void ether_setup(struct net_device *dev) | |
352 | { | |
3b04ddde | 353 | dev->header_ops = ð_header_ops; |
1da177e4 LT |
354 | dev->type = ARPHRD_ETHER; |
355 | dev->hard_header_len = ETH_HLEN; | |
46f25dff | 356 | dev->mtu = ETH_DATA_LEN; |
1da177e4 | 357 | dev->addr_len = ETH_ALEN; |
03d52d7c | 358 | dev->tx_queue_len = 1000; /* Ethernet wants good queues */ |
1da177e4 | 359 | dev->flags = IFF_BROADCAST|IFF_MULTICAST; |
31dda0ae | 360 | dev->priv_flags |= IFF_TX_SKB_SHARING; |
03d52d7c | 361 | |
afc130dd | 362 | eth_broadcast_addr(dev->broadcast); |
1da177e4 LT |
363 | |
364 | } | |
365 | EXPORT_SYMBOL(ether_setup); | |
366 | ||
367 | /** | |
36909ea4 | 368 | * alloc_etherdev_mqs - Allocates and sets up an Ethernet device |
1da177e4 | 369 | * @sizeof_priv: Size of additional driver-private structure to be allocated |
d3e01f71 | 370 | * for this Ethernet device |
36909ea4 | 371 | * @txqs: The number of TX queues this device has. |
3806b4f3 | 372 | * @rxqs: The number of RX queues this device has. |
1da177e4 | 373 | * |
d3e01f71 | 374 | * Fill in the fields of the device structure with Ethernet-generic |
1da177e4 LT |
375 | * values. Basically does everything except registering the device. |
376 | * | |
377 | * Constructs a new net device, complete with a private data area of | |
d3e01f71 | 378 | * size (sizeof_priv). A 32-byte (not bit) alignment is enforced for |
1da177e4 LT |
379 | * this private data area. |
380 | */ | |
381 | ||
36909ea4 TH |
382 | struct net_device *alloc_etherdev_mqs(int sizeof_priv, unsigned int txqs, |
383 | unsigned int rxqs) | |
1da177e4 | 384 | { |
c835a677 TG |
385 | return alloc_netdev_mqs(sizeof_priv, "eth%d", NET_NAME_UNKNOWN, |
386 | ether_setup, txqs, rxqs); | |
1da177e4 | 387 | } |
36909ea4 | 388 | EXPORT_SYMBOL(alloc_etherdev_mqs); |
0795af57 | 389 | |
7ffc49a6 MC |
390 | ssize_t sysfs_format_mac(char *buf, const unsigned char *addr, int len) |
391 | { | |
ae8e9c5a | 392 | return scnprintf(buf, PAGE_SIZE, "%*phC\n", len, addr); |
7ffc49a6 MC |
393 | } |
394 | EXPORT_SYMBOL(sysfs_format_mac); | |
9b174d88 JG |
395 | |
396 | struct sk_buff **eth_gro_receive(struct sk_buff **head, | |
397 | struct sk_buff *skb) | |
398 | { | |
399 | struct sk_buff *p, **pp = NULL; | |
400 | struct ethhdr *eh, *eh2; | |
401 | unsigned int hlen, off_eth; | |
402 | const struct packet_offload *ptype; | |
403 | __be16 type; | |
404 | int flush = 1; | |
405 | ||
406 | off_eth = skb_gro_offset(skb); | |
407 | hlen = off_eth + sizeof(*eh); | |
408 | eh = skb_gro_header_fast(skb, off_eth); | |
409 | if (skb_gro_header_hard(skb, hlen)) { | |
410 | eh = skb_gro_header_slow(skb, hlen, off_eth); | |
411 | if (unlikely(!eh)) | |
412 | goto out; | |
413 | } | |
414 | ||
415 | flush = 0; | |
416 | ||
417 | for (p = *head; p; p = p->next) { | |
418 | if (!NAPI_GRO_CB(p)->same_flow) | |
419 | continue; | |
420 | ||
421 | eh2 = (struct ethhdr *)(p->data + off_eth); | |
422 | if (compare_ether_header(eh, eh2)) { | |
423 | NAPI_GRO_CB(p)->same_flow = 0; | |
424 | continue; | |
425 | } | |
426 | } | |
427 | ||
428 | type = eh->h_proto; | |
429 | ||
430 | rcu_read_lock(); | |
431 | ptype = gro_find_receive_by_type(type); | |
432 | if (ptype == NULL) { | |
433 | flush = 1; | |
434 | goto out_unlock; | |
435 | } | |
436 | ||
437 | skb_gro_pull(skb, sizeof(*eh)); | |
438 | skb_gro_postpull_rcsum(skb, eh, sizeof(*eh)); | |
439 | pp = ptype->callbacks.gro_receive(head, skb); | |
440 | ||
441 | out_unlock: | |
442 | rcu_read_unlock(); | |
443 | out: | |
444 | NAPI_GRO_CB(skb)->flush |= flush; | |
445 | ||
446 | return pp; | |
447 | } | |
448 | EXPORT_SYMBOL(eth_gro_receive); | |
449 | ||
450 | int eth_gro_complete(struct sk_buff *skb, int nhoff) | |
451 | { | |
452 | struct ethhdr *eh = (struct ethhdr *)(skb->data + nhoff); | |
453 | __be16 type = eh->h_proto; | |
454 | struct packet_offload *ptype; | |
455 | int err = -ENOSYS; | |
456 | ||
457 | if (skb->encapsulation) | |
458 | skb_set_inner_mac_header(skb, nhoff); | |
459 | ||
460 | rcu_read_lock(); | |
461 | ptype = gro_find_complete_by_type(type); | |
462 | if (ptype != NULL) | |
463 | err = ptype->callbacks.gro_complete(skb, nhoff + | |
464 | sizeof(struct ethhdr)); | |
465 | ||
466 | rcu_read_unlock(); | |
467 | return err; | |
468 | } | |
469 | EXPORT_SYMBOL(eth_gro_complete); | |
470 | ||
471 | static struct packet_offload eth_packet_offload __read_mostly = { | |
472 | .type = cpu_to_be16(ETH_P_TEB), | |
bdef7de4 | 473 | .priority = 10, |
9b174d88 JG |
474 | .callbacks = { |
475 | .gro_receive = eth_gro_receive, | |
476 | .gro_complete = eth_gro_complete, | |
477 | }, | |
478 | }; | |
479 | ||
480 | static int __init eth_offload_init(void) | |
481 | { | |
482 | dev_add_offload(ð_packet_offload); | |
483 | ||
484 | return 0; | |
485 | } | |
486 | ||
487 | fs_initcall(eth_offload_init); |