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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 if (likely(dev_forward_skb(rcv, skb) == NET_RX_SUCCESS)) {
122 struct pcpu_vstats *stats = this_cpu_ptr(dev->vstats);
123
124 u64_stats_update_begin(&stats->syncp);
125 stats->bytes += length;
126 stats->packets++;
127 u64_stats_update_end(&stats->syncp);
128 } else {
129drop:
130 atomic64_inc(&priv->dropped);
131 }
132 rcu_read_unlock();
133 return NETDEV_TX_OK;
134}
135
136
137
138
139
140static u64 veth_stats_one(struct pcpu_vstats *result, struct net_device *dev)
141{
142 struct veth_priv *priv = netdev_priv(dev);
143 int cpu;
144
145 result->packets = 0;
146 result->bytes = 0;
147 for_each_possible_cpu(cpu) {
148 struct pcpu_vstats *stats = per_cpu_ptr(dev->vstats, cpu);
149 u64 packets, bytes;
150 unsigned int start;
151
152 do {
153 start = u64_stats_fetch_begin_irq(&stats->syncp);
154 packets = stats->packets;
155 bytes = stats->bytes;
156 } while (u64_stats_fetch_retry_irq(&stats->syncp, start));
157 result->packets += packets;
158 result->bytes += bytes;
159 }
160 return atomic64_read(&priv->dropped);
161}
162
163static struct rtnl_link_stats64 *veth_get_stats64(struct net_device *dev,
164 struct rtnl_link_stats64 *tot)
165{
166 struct veth_priv *priv = netdev_priv(dev);
167 struct net_device *peer;
168 struct pcpu_vstats one;
169
170 tot->tx_dropped = veth_stats_one(&one, dev);
171 tot->tx_bytes = one.bytes;
172 tot->tx_packets = one.packets;
173
174 rcu_read_lock();
175 peer = rcu_dereference(priv->peer);
176 if (peer) {
177 tot->rx_dropped = veth_stats_one(&one, peer);
178 tot->rx_bytes = one.bytes;
179 tot->rx_packets = one.packets;
180 }
181 rcu_read_unlock();
182
183 return tot;
184}
185
186
187static void veth_set_multicast_list(struct net_device *dev)
188{
189}
190
191static int veth_open(struct net_device *dev)
192{
193 struct veth_priv *priv = netdev_priv(dev);
194 struct net_device *peer = rtnl_dereference(priv->peer);
195
196 if (!peer)
197 return -ENOTCONN;
198
199 if (peer->flags & IFF_UP) {
200 netif_carrier_on(dev);
201 netif_carrier_on(peer);
202 }
203 return 0;
204}
205
206static int veth_close(struct net_device *dev)
207{
208 struct veth_priv *priv = netdev_priv(dev);
209 struct net_device *peer = rtnl_dereference(priv->peer);
210
211 netif_carrier_off(dev);
212 if (peer)
213 netif_carrier_off(peer);
214
215 return 0;
216}
217
218static int is_valid_veth_mtu(int new_mtu)
219{
220 return new_mtu >= MIN_MTU && new_mtu <= MAX_MTU;
221}
222
223static int veth_change_mtu(struct net_device *dev, int new_mtu)
224{
225 if (!is_valid_veth_mtu(new_mtu))
226 return -EINVAL;
227 dev->mtu = new_mtu;
228 return 0;
229}
230
231static int veth_dev_init(struct net_device *dev)
232{
233 dev->vstats = netdev_alloc_pcpu_stats(struct pcpu_vstats);
234 if (!dev->vstats)
235 return -ENOMEM;
236 return 0;
237}
238
239static void veth_dev_free(struct net_device *dev)
240{
241 free_percpu(dev->vstats);
242 free_netdev(dev);
243}
244
245#ifdef CONFIG_NET_POLL_CONTROLLER
246static void veth_poll_controller(struct net_device *dev)
247{
248
249
250
251
252
253
254
255
256
257}
258#endif
259
260static int veth_get_iflink(const struct net_device *dev)
261{
262 struct veth_priv *priv = netdev_priv(dev);
263 struct net_device *peer;
264 int iflink;
265
266 rcu_read_lock();
267 peer = rcu_dereference(priv->peer);
268 iflink = peer ? peer->ifindex : 0;
269 rcu_read_unlock();
270
271 return iflink;
272}
273
274static const struct net_device_ops veth_netdev_ops = {
275 .ndo_init = veth_dev_init,
276 .ndo_open = veth_open,
277 .ndo_stop = veth_close,
278 .ndo_start_xmit = veth_xmit,
279 .ndo_change_mtu = veth_change_mtu,
280 .ndo_get_stats64 = veth_get_stats64,
281 .ndo_set_rx_mode = veth_set_multicast_list,
282 .ndo_set_mac_address = eth_mac_addr,
283#ifdef CONFIG_NET_POLL_CONTROLLER
284 .ndo_poll_controller = veth_poll_controller,
285#endif
286 .ndo_get_iflink = veth_get_iflink,
287 .ndo_features_check = passthru_features_check,
288};
289
290#define VETH_FEATURES (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_ALL_TSO | \
291 NETIF_F_HW_CSUM | NETIF_F_RXCSUM | NETIF_F_HIGHDMA | \
292 NETIF_F_GSO_GRE | NETIF_F_GSO_UDP_TUNNEL | \
293 NETIF_F_GSO_IPIP | NETIF_F_GSO_SIT | NETIF_F_UFO | \
294 NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX | \
295 NETIF_F_HW_VLAN_STAG_TX | NETIF_F_HW_VLAN_STAG_RX )
296
297static void veth_setup(struct net_device *dev)
298{
299 ether_setup(dev);
300
301 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
302 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
303 dev->priv_flags |= IFF_NO_QUEUE;
304
305 dev->netdev_ops = &veth_netdev_ops;
306 dev->ethtool_ops = &veth_ethtool_ops;
307 dev->features |= NETIF_F_LLTX;
308 dev->features |= VETH_FEATURES;
309 dev->vlan_features = dev->features &
310 ~(NETIF_F_HW_VLAN_CTAG_TX |
311 NETIF_F_HW_VLAN_STAG_TX |
312 NETIF_F_HW_VLAN_CTAG_RX |
313 NETIF_F_HW_VLAN_STAG_RX);
314 dev->destructor = veth_dev_free;
315
316 dev->hw_features = VETH_FEATURES;
317 dev->hw_enc_features = VETH_FEATURES;
318}
319
320
321
322
323
324static int veth_validate(struct nlattr *tb[], struct nlattr *data[])
325{
326 if (tb[IFLA_ADDRESS]) {
327 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
328 return -EINVAL;
329 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
330 return -EADDRNOTAVAIL;
331 }
332 if (tb[IFLA_MTU]) {
333 if (!is_valid_veth_mtu(nla_get_u32(tb[IFLA_MTU])))
334 return -EINVAL;
335 }
336 return 0;
337}
338
339static struct rtnl_link_ops veth_link_ops;
340
341static int veth_newlink(struct net *src_net, struct net_device *dev,
342 struct nlattr *tb[], struct nlattr *data[])
343{
344 int err;
345 struct net_device *peer;
346 struct veth_priv *priv;
347 char ifname[IFNAMSIZ];
348 struct nlattr *peer_tb[IFLA_MAX + 1], **tbp;
349 unsigned char name_assign_type;
350 struct ifinfomsg *ifmp;
351 struct net *net;
352
353
354
355
356 if (data != NULL && data[VETH_INFO_PEER] != NULL) {
357 struct nlattr *nla_peer;
358
359 nla_peer = data[VETH_INFO_PEER];
360 ifmp = nla_data(nla_peer);
361 err = rtnl_nla_parse_ifla(peer_tb,
362 nla_data(nla_peer) + sizeof(struct ifinfomsg),
363 nla_len(nla_peer) - sizeof(struct ifinfomsg));
364 if (err < 0)
365 return err;
366
367 err = veth_validate(peer_tb, NULL);
368 if (err < 0)
369 return err;
370
371 tbp = peer_tb;
372 } else {
373 ifmp = NULL;
374 tbp = tb;
375 }
376
377 if (tbp[IFLA_IFNAME]) {
378 nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
379 name_assign_type = NET_NAME_USER;
380 } else {
381 snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
382 name_assign_type = NET_NAME_ENUM;
383 }
384
385 net = rtnl_link_get_net(src_net, tbp);
386 if (IS_ERR(net))
387 return PTR_ERR(net);
388
389 peer = rtnl_create_link(net, ifname, name_assign_type,
390 &veth_link_ops, tbp);
391 if (IS_ERR(peer)) {
392 put_net(net);
393 return PTR_ERR(peer);
394 }
395
396 if (tbp[IFLA_ADDRESS] == NULL)
397 eth_hw_addr_random(peer);
398
399 if (ifmp && (dev->ifindex != 0))
400 peer->ifindex = ifmp->ifi_index;
401
402 err = register_netdevice(peer);
403 put_net(net);
404 net = NULL;
405 if (err < 0)
406 goto err_register_peer;
407
408 netif_carrier_off(peer);
409
410 err = rtnl_configure_link(peer, ifmp);
411 if (err < 0)
412 goto err_configure_peer;
413
414
415
416
417
418
419
420
421 if (tb[IFLA_ADDRESS] == NULL)
422 eth_hw_addr_random(dev);
423
424 if (tb[IFLA_IFNAME])
425 nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
426 else
427 snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
428
429 err = register_netdevice(dev);
430 if (err < 0)
431 goto err_register_dev;
432
433 netif_carrier_off(dev);
434
435
436
437
438
439 priv = netdev_priv(dev);
440 rcu_assign_pointer(priv->peer, peer);
441
442 priv = netdev_priv(peer);
443 rcu_assign_pointer(priv->peer, dev);
444 return 0;
445
446err_register_dev:
447
448err_configure_peer:
449 unregister_netdevice(peer);
450 return err;
451
452err_register_peer:
453 free_netdev(peer);
454 return err;
455}
456
457static void veth_dellink(struct net_device *dev, struct list_head *head)
458{
459 struct veth_priv *priv;
460 struct net_device *peer;
461
462 priv = netdev_priv(dev);
463 peer = rtnl_dereference(priv->peer);
464
465
466
467
468
469 RCU_INIT_POINTER(priv->peer, NULL);
470 unregister_netdevice_queue(dev, head);
471
472 if (peer) {
473 priv = netdev_priv(peer);
474 RCU_INIT_POINTER(priv->peer, NULL);
475 unregister_netdevice_queue(peer, head);
476 }
477}
478
479static const struct nla_policy veth_policy[VETH_INFO_MAX + 1] = {
480 [VETH_INFO_PEER] = { .len = sizeof(struct ifinfomsg) },
481};
482
483static struct net *veth_get_link_net(const struct net_device *dev)
484{
485 struct veth_priv *priv = netdev_priv(dev);
486 struct net_device *peer = rtnl_dereference(priv->peer);
487
488 return peer ? dev_net(peer) : dev_net(dev);
489}
490
491static struct rtnl_link_ops veth_link_ops = {
492 .kind = DRV_NAME,
493 .priv_size = sizeof(struct veth_priv),
494 .setup = veth_setup,
495 .validate = veth_validate,
496 .newlink = veth_newlink,
497 .dellink = veth_dellink,
498 .policy = veth_policy,
499 .maxtype = VETH_INFO_MAX,
500 .get_link_net = veth_get_link_net,
501};
502
503
504
505
506
507static __init int veth_init(void)
508{
509 return rtnl_link_register(&veth_link_ops);
510}
511
512static __exit void veth_exit(void)
513{
514 rtnl_link_unregister(&veth_link_ops);
515}
516
517module_init(veth_init);
518module_exit(veth_exit);
519
520MODULE_DESCRIPTION("Virtual Ethernet Tunnel");
521MODULE_LICENSE("GPL v2");
522MODULE_ALIAS_RTNL_LINK(DRV_NAME);
523
