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11#include <linux/netdevice.h>
12#include <linux/slab.h>
13#include <linux/ethtool.h>
14#include <linux/etherdevice.h>
15#include <linux/u64_stats_sync.h>
16
17#include <net/rtnetlink.h>
18#include <net/dst.h>
19#include <net/xfrm.h>
20#include <linux/veth.h>
21#include <linux/module.h>
22
23#define DRV_NAME "veth"
24#define DRV_VERSION "1.0"
25
26#define MIN_MTU 68
27#define MAX_MTU 65535
28
29struct pcpu_vstats {
30 u64 packets;
31 u64 bytes;
32 struct u64_stats_sync syncp;
33};
34
35struct veth_priv {
36 struct net_device __rcu *peer;
37 atomic64_t dropped;
38};
39
40
41
42
43
44static struct {
45 const char string[ETH_GSTRING_LEN];
46} ethtool_stats_keys[] = {
47 { "peer_ifindex" },
48};
49
50static int veth_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
51{
52 cmd->supported = 0;
53 cmd->advertising = 0;
54 ethtool_cmd_speed_set(cmd, SPEED_10000);
55 cmd->duplex = DUPLEX_FULL;
56 cmd->port = PORT_TP;
57 cmd->phy_address = 0;
58 cmd->transceiver = XCVR_INTERNAL;
59 cmd->autoneg = AUTONEG_DISABLE;
60 cmd->maxtxpkt = 0;
61 cmd->maxrxpkt = 0;
62 return 0;
63}
64
65static void veth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
66{
67 strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
68 strlcpy(info->version, DRV_VERSION, sizeof(info->version));
69}
70
71static void veth_get_strings(struct net_device *dev, u32 stringset, u8 *buf)
72{
73 switch(stringset) {
74 case ETH_SS_STATS:
75 memcpy(buf, ðtool_stats_keys, sizeof(ethtool_stats_keys));
76 break;
77 }
78}
79
80static int veth_get_sset_count(struct net_device *dev, int sset)
81{
82 switch (sset) {
83 case ETH_SS_STATS:
84 return ARRAY_SIZE(ethtool_stats_keys);
85 default:
86 return -EOPNOTSUPP;
87 }
88}
89
90static void veth_get_ethtool_stats(struct net_device *dev,
91 struct ethtool_stats *stats, u64 *data)
92{
93 struct veth_priv *priv = netdev_priv(dev);
94 struct net_device *peer = rtnl_dereference(priv->peer);
95
96 data[0] = peer ? peer->ifindex : 0;
97}
98
99static const struct ethtool_ops veth_ethtool_ops = {
100 .get_settings = veth_get_settings,
101 .get_drvinfo = veth_get_drvinfo,
102 .get_link = ethtool_op_get_link,
103 .get_strings = veth_get_strings,
104 .get_sset_count = veth_get_sset_count,
105 .get_ethtool_stats = veth_get_ethtool_stats,
106};
107
108static netdev_tx_t veth_xmit(struct sk_buff *skb, struct net_device *dev)
109{
110 struct veth_priv *priv = netdev_priv(dev);
111 struct net_device *rcv;
112 int length = skb->len;
113
114 rcu_read_lock();
115 rcv = rcu_dereference(priv->peer);
116 if (unlikely(!rcv)) {
117 kfree_skb(skb);
118 goto drop;
119 }
120
121
122
123 if (skb->ip_summed == CHECKSUM_NONE &&
124 rcv->features & NETIF_F_RXCSUM)
125 skb->ip_summed = CHECKSUM_UNNECESSARY;
126
127 if (likely(dev_forward_skb(rcv, skb) == NET_RX_SUCCESS)) {
128 struct pcpu_vstats *stats = this_cpu_ptr(dev->vstats);
129
130 u64_stats_update_begin(&stats->syncp);
131 stats->bytes += length;
132 stats->packets++;
133 u64_stats_update_end(&stats->syncp);
134 } else {
135drop:
136 atomic64_inc(&priv->dropped);
137 }
138 rcu_read_unlock();
139 return NETDEV_TX_OK;
140}
141
142
143
144
145
146static u64 veth_stats_one(struct pcpu_vstats *result, struct net_device *dev)
147{
148 struct veth_priv *priv = netdev_priv(dev);
149 int cpu;
150
151 result->packets = 0;
152 result->bytes = 0;
153 for_each_possible_cpu(cpu) {
154 struct pcpu_vstats *stats = per_cpu_ptr(dev->vstats, cpu);
155 u64 packets, bytes;
156 unsigned int start;
157
158 do {
159 start = u64_stats_fetch_begin_irq(&stats->syncp);
160 packets = stats->packets;
161 bytes = stats->bytes;
162 } while (u64_stats_fetch_retry_irq(&stats->syncp, start));
163 result->packets += packets;
164 result->bytes += bytes;
165 }
166 return atomic64_read(&priv->dropped);
167}
168
169static struct rtnl_link_stats64 *veth_get_stats64(struct net_device *dev,
170 struct rtnl_link_stats64 *tot)
171{
172 struct veth_priv *priv = netdev_priv(dev);
173 struct net_device *peer;
174 struct pcpu_vstats one;
175
176 tot->tx_dropped = veth_stats_one(&one, dev);
177 tot->tx_bytes = one.bytes;
178 tot->tx_packets = one.packets;
179
180 rcu_read_lock();
181 peer = rcu_dereference(priv->peer);
182 if (peer) {
183 tot->rx_dropped = veth_stats_one(&one, peer);
184 tot->rx_bytes = one.bytes;
185 tot->rx_packets = one.packets;
186 }
187 rcu_read_unlock();
188
189 return tot;
190}
191
192
193static void veth_set_multicast_list(struct net_device *dev)
194{
195}
196
197static int veth_open(struct net_device *dev)
198{
199 struct veth_priv *priv = netdev_priv(dev);
200 struct net_device *peer = rtnl_dereference(priv->peer);
201
202 if (!peer)
203 return -ENOTCONN;
204
205 if (peer->flags & IFF_UP) {
206 netif_carrier_on(dev);
207 netif_carrier_on(peer);
208 }
209 return 0;
210}
211
212static int veth_close(struct net_device *dev)
213{
214 struct veth_priv *priv = netdev_priv(dev);
215 struct net_device *peer = rtnl_dereference(priv->peer);
216
217 netif_carrier_off(dev);
218 if (peer)
219 netif_carrier_off(peer);
220
221 return 0;
222}
223
224static int is_valid_veth_mtu(int new_mtu)
225{
226 return new_mtu >= MIN_MTU && new_mtu <= MAX_MTU;
227}
228
229static int veth_change_mtu(struct net_device *dev, int new_mtu)
230{
231 if (!is_valid_veth_mtu(new_mtu))
232 return -EINVAL;
233 dev->mtu = new_mtu;
234 return 0;
235}
236
237static int veth_dev_init(struct net_device *dev)
238{
239 dev->vstats = netdev_alloc_pcpu_stats(struct pcpu_vstats);
240 if (!dev->vstats)
241 return -ENOMEM;
242 return 0;
243}
244
245static void veth_dev_free(struct net_device *dev)
246{
247 free_percpu(dev->vstats);
248 free_netdev(dev);
249}
250
251#ifdef CONFIG_NET_POLL_CONTROLLER
252static void veth_poll_controller(struct net_device *dev)
253{
254
255
256
257
258
259
260
261
262
263}
264#endif
265
266static int veth_get_iflink(const struct net_device *dev)
267{
268 struct veth_priv *priv = netdev_priv(dev);
269 struct net_device *peer;
270 int iflink;
271
272 rcu_read_lock();
273 peer = rcu_dereference(priv->peer);
274 iflink = peer ? peer->ifindex : 0;
275 rcu_read_unlock();
276
277 return iflink;
278}
279
280static const struct net_device_ops veth_netdev_ops = {
281 .ndo_init = veth_dev_init,
282 .ndo_open = veth_open,
283 .ndo_stop = veth_close,
284 .ndo_start_xmit = veth_xmit,
285 .ndo_change_mtu = veth_change_mtu,
286 .ndo_get_stats64 = veth_get_stats64,
287 .ndo_set_rx_mode = veth_set_multicast_list,
288 .ndo_set_mac_address = eth_mac_addr,
289#ifdef CONFIG_NET_POLL_CONTROLLER
290 .ndo_poll_controller = veth_poll_controller,
291#endif
292 .ndo_get_iflink = veth_get_iflink,
293 .ndo_features_check = passthru_features_check,
294};
295
296#define VETH_FEATURES (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_ALL_TSO | \
297 NETIF_F_HW_CSUM | NETIF_F_RXCSUM | NETIF_F_HIGHDMA | \
298 NETIF_F_GSO_GRE | NETIF_F_GSO_UDP_TUNNEL | \
299 NETIF_F_GSO_IPIP | NETIF_F_GSO_SIT | NETIF_F_UFO | \
300 NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX | \
301 NETIF_F_HW_VLAN_STAG_TX | NETIF_F_HW_VLAN_STAG_RX )
302
303static void veth_setup(struct net_device *dev)
304{
305 ether_setup(dev);
306
307 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
308 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
309 dev->priv_flags |= IFF_NO_QUEUE;
310
311 dev->netdev_ops = &veth_netdev_ops;
312 dev->ethtool_ops = &veth_ethtool_ops;
313 dev->features |= NETIF_F_LLTX;
314 dev->features |= VETH_FEATURES;
315 dev->vlan_features = dev->features &
316 ~(NETIF_F_HW_VLAN_CTAG_TX |
317 NETIF_F_HW_VLAN_STAG_TX |
318 NETIF_F_HW_VLAN_CTAG_RX |
319 NETIF_F_HW_VLAN_STAG_RX);
320 dev->destructor = veth_dev_free;
321
322 dev->hw_features = VETH_FEATURES;
323 dev->hw_enc_features = VETH_FEATURES;
324}
325
326
327
328
329
330static int veth_validate(struct nlattr *tb[], struct nlattr *data[])
331{
332 if (tb[IFLA_ADDRESS]) {
333 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
334 return -EINVAL;
335 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
336 return -EADDRNOTAVAIL;
337 }
338 if (tb[IFLA_MTU]) {
339 if (!is_valid_veth_mtu(nla_get_u32(tb[IFLA_MTU])))
340 return -EINVAL;
341 }
342 return 0;
343}
344
345static struct rtnl_link_ops veth_link_ops;
346
347static int veth_newlink(struct net *src_net, struct net_device *dev,
348 struct nlattr *tb[], struct nlattr *data[])
349{
350 int err;
351 struct net_device *peer;
352 struct veth_priv *priv;
353 char ifname[IFNAMSIZ];
354 struct nlattr *peer_tb[IFLA_MAX + 1], **tbp;
355 unsigned char name_assign_type;
356 struct ifinfomsg *ifmp;
357 struct net *net;
358
359
360
361
362 if (data != NULL && data[VETH_INFO_PEER] != NULL) {
363 struct nlattr *nla_peer;
364
365 nla_peer = data[VETH_INFO_PEER];
366 ifmp = nla_data(nla_peer);
367 err = rtnl_nla_parse_ifla(peer_tb,
368 nla_data(nla_peer) + sizeof(struct ifinfomsg),
369 nla_len(nla_peer) - sizeof(struct ifinfomsg));
370 if (err < 0)
371 return err;
372
373 err = veth_validate(peer_tb, NULL);
374 if (err < 0)
375 return err;
376
377 tbp = peer_tb;
378 } else {
379 ifmp = NULL;
380 tbp = tb;
381 }
382
383 if (tbp[IFLA_IFNAME]) {
384 nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
385 name_assign_type = NET_NAME_USER;
386 } else {
387 snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
388 name_assign_type = NET_NAME_ENUM;
389 }
390
391 net = rtnl_link_get_net(src_net, tbp);
392 if (IS_ERR(net))
393 return PTR_ERR(net);
394
395 peer = rtnl_create_link(net, ifname, name_assign_type,
396 &veth_link_ops, tbp);
397 if (IS_ERR(peer)) {
398 put_net(net);
399 return PTR_ERR(peer);
400 }
401
402 if (tbp[IFLA_ADDRESS] == NULL)
403 eth_hw_addr_random(peer);
404
405 if (ifmp && (dev->ifindex != 0))
406 peer->ifindex = ifmp->ifi_index;
407
408 err = register_netdevice(peer);
409 put_net(net);
410 net = NULL;
411 if (err < 0)
412 goto err_register_peer;
413
414 netif_carrier_off(peer);
415
416 err = rtnl_configure_link(peer, ifmp);
417 if (err < 0)
418 goto err_configure_peer;
419
420
421
422
423
424
425
426
427 if (tb[IFLA_ADDRESS] == NULL)
428 eth_hw_addr_random(dev);
429
430 if (tb[IFLA_IFNAME])
431 nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
432 else
433 snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
434
435 err = register_netdevice(dev);
436 if (err < 0)
437 goto err_register_dev;
438
439 netif_carrier_off(dev);
440
441
442
443
444
445 priv = netdev_priv(dev);
446 rcu_assign_pointer(priv->peer, peer);
447
448 priv = netdev_priv(peer);
449 rcu_assign_pointer(priv->peer, dev);
450 return 0;
451
452err_register_dev:
453
454err_configure_peer:
455 unregister_netdevice(peer);
456 return err;
457
458err_register_peer:
459 free_netdev(peer);
460 return err;
461}
462
463static void veth_dellink(struct net_device *dev, struct list_head *head)
464{
465 struct veth_priv *priv;
466 struct net_device *peer;
467
468 priv = netdev_priv(dev);
469 peer = rtnl_dereference(priv->peer);
470
471
472
473
474
475 RCU_INIT_POINTER(priv->peer, NULL);
476 unregister_netdevice_queue(dev, head);
477
478 if (peer) {
479 priv = netdev_priv(peer);
480 RCU_INIT_POINTER(priv->peer, NULL);
481 unregister_netdevice_queue(peer, head);
482 }
483}
484
485static const struct nla_policy veth_policy[VETH_INFO_MAX + 1] = {
486 [VETH_INFO_PEER] = { .len = sizeof(struct ifinfomsg) },
487};
488
489static struct net *veth_get_link_net(const struct net_device *dev)
490{
491 struct veth_priv *priv = netdev_priv(dev);
492 struct net_device *peer = rtnl_dereference(priv->peer);
493
494 return peer ? dev_net(peer) : dev_net(dev);
495}
496
497static struct rtnl_link_ops veth_link_ops = {
498 .kind = DRV_NAME,
499 .priv_size = sizeof(struct veth_priv),
500 .setup = veth_setup,
501 .validate = veth_validate,
502 .newlink = veth_newlink,
503 .dellink = veth_dellink,
504 .policy = veth_policy,
505 .maxtype = VETH_INFO_MAX,
506 .get_link_net = veth_get_link_net,
507};
508
509
510
511
512
513static __init int veth_init(void)
514{
515 return rtnl_link_register(&veth_link_ops);
516}
517
518static __exit void veth_exit(void)
519{
520 rtnl_link_unregister(&veth_link_ops);
521}
522
523module_init(veth_init);
524module_exit(veth_exit);
525
526MODULE_DESCRIPTION("Virtual Ethernet Tunnel");
527MODULE_LICENSE("GPL v2");
528MODULE_ALIAS_RTNL_LINK(DRV_NAME);
529
