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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};
294
295#define VETH_FEATURES (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_ALL_TSO | \
296 NETIF_F_HW_CSUM | NETIF_F_RXCSUM | NETIF_F_HIGHDMA | \
297 NETIF_F_GSO_GRE | NETIF_F_GSO_UDP_TUNNEL | \
298 NETIF_F_GSO_IPIP | NETIF_F_GSO_SIT | NETIF_F_UFO | \
299 NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX | \
300 NETIF_F_HW_VLAN_STAG_TX | NETIF_F_HW_VLAN_STAG_RX )
301
302static void veth_setup(struct net_device *dev)
303{
304 ether_setup(dev);
305
306 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
307 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
308
309 dev->netdev_ops = &veth_netdev_ops;
310 dev->ethtool_ops = &veth_ethtool_ops;
311 dev->features |= NETIF_F_LLTX;
312 dev->features |= VETH_FEATURES;
313 dev->vlan_features = dev->features &
314 ~(NETIF_F_HW_VLAN_CTAG_TX |
315 NETIF_F_HW_VLAN_STAG_TX |
316 NETIF_F_HW_VLAN_CTAG_RX |
317 NETIF_F_HW_VLAN_STAG_RX);
318 dev->destructor = veth_dev_free;
319
320 dev->hw_features = VETH_FEATURES;
321 dev->hw_enc_features = VETH_FEATURES;
322}
323
324
325
326
327
328static int veth_validate(struct nlattr *tb[], struct nlattr *data[])
329{
330 if (tb[IFLA_ADDRESS]) {
331 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
332 return -EINVAL;
333 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
334 return -EADDRNOTAVAIL;
335 }
336 if (tb[IFLA_MTU]) {
337 if (!is_valid_veth_mtu(nla_get_u32(tb[IFLA_MTU])))
338 return -EINVAL;
339 }
340 return 0;
341}
342
343static struct rtnl_link_ops veth_link_ops;
344
345static int veth_newlink(struct net *src_net, struct net_device *dev,
346 struct nlattr *tb[], struct nlattr *data[])
347{
348 int err;
349 struct net_device *peer;
350 struct veth_priv *priv;
351 char ifname[IFNAMSIZ];
352 struct nlattr *peer_tb[IFLA_MAX + 1], **tbp;
353 unsigned char name_assign_type;
354 struct ifinfomsg *ifmp;
355 struct net *net;
356
357
358
359
360 if (data != NULL && data[VETH_INFO_PEER] != NULL) {
361 struct nlattr *nla_peer;
362
363 nla_peer = data[VETH_INFO_PEER];
364 ifmp = nla_data(nla_peer);
365 err = rtnl_nla_parse_ifla(peer_tb,
366 nla_data(nla_peer) + sizeof(struct ifinfomsg),
367 nla_len(nla_peer) - sizeof(struct ifinfomsg));
368 if (err < 0)
369 return err;
370
371 err = veth_validate(peer_tb, NULL);
372 if (err < 0)
373 return err;
374
375 tbp = peer_tb;
376 } else {
377 ifmp = NULL;
378 tbp = tb;
379 }
380
381 if (tbp[IFLA_IFNAME]) {
382 nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
383 name_assign_type = NET_NAME_USER;
384 } else {
385 snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
386 name_assign_type = NET_NAME_ENUM;
387 }
388
389 net = rtnl_link_get_net(src_net, tbp);
390 if (IS_ERR(net))
391 return PTR_ERR(net);
392
393 peer = rtnl_create_link(net, ifname, name_assign_type,
394 &veth_link_ops, tbp);
395 if (IS_ERR(peer)) {
396 put_net(net);
397 return PTR_ERR(peer);
398 }
399
400 if (tbp[IFLA_ADDRESS] == NULL)
401 eth_hw_addr_random(peer);
402
403 if (ifmp && (dev->ifindex != 0))
404 peer->ifindex = ifmp->ifi_index;
405
406 err = register_netdevice(peer);
407 put_net(net);
408 net = NULL;
409 if (err < 0)
410 goto err_register_peer;
411
412 netif_carrier_off(peer);
413
414 err = rtnl_configure_link(peer, ifmp);
415 if (err < 0)
416 goto err_configure_peer;
417
418
419
420
421
422
423
424
425 if (tb[IFLA_ADDRESS] == NULL)
426 eth_hw_addr_random(dev);
427
428 if (tb[IFLA_IFNAME])
429 nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
430 else
431 snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
432
433 err = register_netdevice(dev);
434 if (err < 0)
435 goto err_register_dev;
436
437 netif_carrier_off(dev);
438
439
440
441
442
443 priv = netdev_priv(dev);
444 rcu_assign_pointer(priv->peer, peer);
445
446 priv = netdev_priv(peer);
447 rcu_assign_pointer(priv->peer, dev);
448 return 0;
449
450err_register_dev:
451
452err_configure_peer:
453 unregister_netdevice(peer);
454 return err;
455
456err_register_peer:
457 free_netdev(peer);
458 return err;
459}
460
461static void veth_dellink(struct net_device *dev, struct list_head *head)
462{
463 struct veth_priv *priv;
464 struct net_device *peer;
465
466 priv = netdev_priv(dev);
467 peer = rtnl_dereference(priv->peer);
468
469
470
471
472
473 RCU_INIT_POINTER(priv->peer, NULL);
474 unregister_netdevice_queue(dev, head);
475
476 if (peer) {
477 priv = netdev_priv(peer);
478 RCU_INIT_POINTER(priv->peer, NULL);
479 unregister_netdevice_queue(peer, head);
480 }
481}
482
483static const struct nla_policy veth_policy[VETH_INFO_MAX + 1] = {
484 [VETH_INFO_PEER] = { .len = sizeof(struct ifinfomsg) },
485};
486
487static struct net *veth_get_link_net(const struct net_device *dev)
488{
489 struct veth_priv *priv = netdev_priv(dev);
490 struct net_device *peer = rtnl_dereference(priv->peer);
491
492 return peer ? dev_net(peer) : dev_net(dev);
493}
494
495static struct rtnl_link_ops veth_link_ops = {
496 .kind = DRV_NAME,
497 .priv_size = sizeof(struct veth_priv),
498 .setup = veth_setup,
499 .validate = veth_validate,
500 .newlink = veth_newlink,
501 .dellink = veth_dellink,
502 .policy = veth_policy,
503 .maxtype = VETH_INFO_MAX,
504 .get_link_net = veth_get_link_net,
505};
506
507
508
509
510
511static __init int veth_init(void)
512{
513 return rtnl_link_register(&veth_link_ops);
514}
515
516static __exit void veth_exit(void)
517{
518 rtnl_link_unregister(&veth_link_ops);
519}
520
521module_init(veth_init);
522module_exit(veth_exit);
523
524MODULE_DESCRIPTION("Virtual Ethernet Tunnel");
525MODULE_LICENSE("GPL v2");
526MODULE_ALIAS_RTNL_LINK(DRV_NAME);
527
