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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 unsigned requested_headroom;
39};
40
41
42
43
44
45static struct {
46 const char string[ETH_GSTRING_LEN];
47} ethtool_stats_keys[] = {
48 { "peer_ifindex" },
49};
50
51static int veth_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
52{
53 cmd->supported = 0;
54 cmd->advertising = 0;
55 ethtool_cmd_speed_set(cmd, SPEED_10000);
56 cmd->duplex = DUPLEX_FULL;
57 cmd->port = PORT_TP;
58 cmd->phy_address = 0;
59 cmd->transceiver = XCVR_INTERNAL;
60 cmd->autoneg = AUTONEG_DISABLE;
61 cmd->maxtxpkt = 0;
62 cmd->maxrxpkt = 0;
63 return 0;
64}
65
66static void veth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
67{
68 strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
69 strlcpy(info->version, DRV_VERSION, sizeof(info->version));
70}
71
72static void veth_get_strings(struct net_device *dev, u32 stringset, u8 *buf)
73{
74 switch(stringset) {
75 case ETH_SS_STATS:
76 memcpy(buf, ðtool_stats_keys, sizeof(ethtool_stats_keys));
77 break;
78 }
79}
80
81static int veth_get_sset_count(struct net_device *dev, int sset)
82{
83 switch (sset) {
84 case ETH_SS_STATS:
85 return ARRAY_SIZE(ethtool_stats_keys);
86 default:
87 return -EOPNOTSUPP;
88 }
89}
90
91static void veth_get_ethtool_stats(struct net_device *dev,
92 struct ethtool_stats *stats, u64 *data)
93{
94 struct veth_priv *priv = netdev_priv(dev);
95 struct net_device *peer = rtnl_dereference(priv->peer);
96
97 data[0] = peer ? peer->ifindex : 0;
98}
99
100static const struct ethtool_ops veth_ethtool_ops = {
101 .get_settings = veth_get_settings,
102 .get_drvinfo = veth_get_drvinfo,
103 .get_link = ethtool_op_get_link,
104 .get_strings = veth_get_strings,
105 .get_sset_count = veth_get_sset_count,
106 .get_ethtool_stats = veth_get_ethtool_stats,
107};
108
109static netdev_tx_t veth_xmit(struct sk_buff *skb, struct net_device *dev)
110{
111 struct veth_priv *priv = netdev_priv(dev);
112 struct net_device *rcv;
113 int length = skb->len;
114
115 rcu_read_lock();
116 rcv = rcu_dereference(priv->peer);
117 if (unlikely(!rcv)) {
118 kfree_skb(skb);
119 goto drop;
120 }
121
122 if (likely(dev_forward_skb(rcv, skb) == NET_RX_SUCCESS)) {
123 struct pcpu_vstats *stats = this_cpu_ptr(dev->vstats);
124
125 u64_stats_update_begin(&stats->syncp);
126 stats->bytes += length;
127 stats->packets++;
128 u64_stats_update_end(&stats->syncp);
129 } else {
130drop:
131 atomic64_inc(&priv->dropped);
132 }
133 rcu_read_unlock();
134 return NETDEV_TX_OK;
135}
136
137
138
139
140
141static u64 veth_stats_one(struct pcpu_vstats *result, struct net_device *dev)
142{
143 struct veth_priv *priv = netdev_priv(dev);
144 int cpu;
145
146 result->packets = 0;
147 result->bytes = 0;
148 for_each_possible_cpu(cpu) {
149 struct pcpu_vstats *stats = per_cpu_ptr(dev->vstats, cpu);
150 u64 packets, bytes;
151 unsigned int start;
152
153 do {
154 start = u64_stats_fetch_begin_irq(&stats->syncp);
155 packets = stats->packets;
156 bytes = stats->bytes;
157 } while (u64_stats_fetch_retry_irq(&stats->syncp, start));
158 result->packets += packets;
159 result->bytes += bytes;
160 }
161 return atomic64_read(&priv->dropped);
162}
163
164static struct rtnl_link_stats64 *veth_get_stats64(struct net_device *dev,
165 struct rtnl_link_stats64 *tot)
166{
167 struct veth_priv *priv = netdev_priv(dev);
168 struct net_device *peer;
169 struct pcpu_vstats one;
170
171 tot->tx_dropped = veth_stats_one(&one, dev);
172 tot->tx_bytes = one.bytes;
173 tot->tx_packets = one.packets;
174
175 rcu_read_lock();
176 peer = rcu_dereference(priv->peer);
177 if (peer) {
178 tot->rx_dropped = veth_stats_one(&one, peer);
179 tot->rx_bytes = one.bytes;
180 tot->rx_packets = one.packets;
181 }
182 rcu_read_unlock();
183
184 return tot;
185}
186
187
188static void veth_set_multicast_list(struct net_device *dev)
189{
190}
191
192static int veth_open(struct net_device *dev)
193{
194 struct veth_priv *priv = netdev_priv(dev);
195 struct net_device *peer = rtnl_dereference(priv->peer);
196
197 if (!peer)
198 return -ENOTCONN;
199
200 if (peer->flags & IFF_UP) {
201 netif_carrier_on(dev);
202 netif_carrier_on(peer);
203 }
204 return 0;
205}
206
207static int veth_close(struct net_device *dev)
208{
209 struct veth_priv *priv = netdev_priv(dev);
210 struct net_device *peer = rtnl_dereference(priv->peer);
211
212 netif_carrier_off(dev);
213 if (peer)
214 netif_carrier_off(peer);
215
216 return 0;
217}
218
219static int is_valid_veth_mtu(int new_mtu)
220{
221 return new_mtu >= MIN_MTU && new_mtu <= MAX_MTU;
222}
223
224static int veth_change_mtu(struct net_device *dev, int new_mtu)
225{
226 if (!is_valid_veth_mtu(new_mtu))
227 return -EINVAL;
228 dev->mtu = new_mtu;
229 return 0;
230}
231
232static int veth_dev_init(struct net_device *dev)
233{
234 dev->vstats = netdev_alloc_pcpu_stats(struct pcpu_vstats);
235 if (!dev->vstats)
236 return -ENOMEM;
237 return 0;
238}
239
240static void veth_dev_free(struct net_device *dev)
241{
242 free_percpu(dev->vstats);
243 free_netdev(dev);
244}
245
246#ifdef CONFIG_NET_POLL_CONTROLLER
247static void veth_poll_controller(struct net_device *dev)
248{
249
250
251
252
253
254
255
256
257
258}
259#endif
260
261static int veth_get_iflink(const struct net_device *dev)
262{
263 struct veth_priv *priv = netdev_priv(dev);
264 struct net_device *peer;
265 int iflink;
266
267 rcu_read_lock();
268 peer = rcu_dereference(priv->peer);
269 iflink = peer ? peer->ifindex : 0;
270 rcu_read_unlock();
271
272 return iflink;
273}
274
275static void veth_set_rx_headroom(struct net_device *dev, int new_hr)
276{
277 struct veth_priv *peer_priv, *priv = netdev_priv(dev);
278 struct net_device *peer;
279
280 if (new_hr < 0)
281 new_hr = 0;
282
283 rcu_read_lock();
284 peer = rcu_dereference(priv->peer);
285 if (unlikely(!peer))
286 goto out;
287
288 peer_priv = netdev_priv(peer);
289 priv->requested_headroom = new_hr;
290 new_hr = max(priv->requested_headroom, peer_priv->requested_headroom);
291 dev->needed_headroom = new_hr;
292 peer->needed_headroom = new_hr;
293
294out:
295 rcu_read_unlock();
296}
297
298static const struct net_device_ops veth_netdev_ops = {
299 .ndo_init = veth_dev_init,
300 .ndo_open = veth_open,
301 .ndo_stop = veth_close,
302 .ndo_start_xmit = veth_xmit,
303 .ndo_change_mtu = veth_change_mtu,
304 .ndo_get_stats64 = veth_get_stats64,
305 .ndo_set_rx_mode = veth_set_multicast_list,
306 .ndo_set_mac_address = eth_mac_addr,
307#ifdef CONFIG_NET_POLL_CONTROLLER
308 .ndo_poll_controller = veth_poll_controller,
309#endif
310 .ndo_get_iflink = veth_get_iflink,
311 .ndo_features_check = passthru_features_check,
312 .ndo_set_rx_headroom = veth_set_rx_headroom,
313};
314
315#define VETH_FEATURES (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HW_CSUM | \
316 NETIF_F_RXCSUM | NETIF_F_HIGHDMA | \
317 NETIF_F_GSO_SOFTWARE | NETIF_F_GSO_ENCAP_ALL | \
318 NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX | \
319 NETIF_F_HW_VLAN_STAG_TX | NETIF_F_HW_VLAN_STAG_RX )
320
321static void veth_setup(struct net_device *dev)
322{
323 ether_setup(dev);
324
325 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
326 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
327 dev->priv_flags |= IFF_NO_QUEUE;
328 dev->priv_flags |= IFF_PHONY_HEADROOM;
329
330 dev->netdev_ops = &veth_netdev_ops;
331 dev->ethtool_ops = &veth_ethtool_ops;
332 dev->features |= NETIF_F_LLTX;
333 dev->features |= VETH_FEATURES;
334 dev->vlan_features = dev->features &
335 ~(NETIF_F_HW_VLAN_CTAG_TX |
336 NETIF_F_HW_VLAN_STAG_TX |
337 NETIF_F_HW_VLAN_CTAG_RX |
338 NETIF_F_HW_VLAN_STAG_RX);
339 dev->destructor = veth_dev_free;
340
341 dev->hw_features = VETH_FEATURES;
342 dev->hw_enc_features = VETH_FEATURES;
343}
344
345
346
347
348
349static int veth_validate(struct nlattr *tb[], struct nlattr *data[])
350{
351 if (tb[IFLA_ADDRESS]) {
352 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
353 return -EINVAL;
354 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
355 return -EADDRNOTAVAIL;
356 }
357 if (tb[IFLA_MTU]) {
358 if (!is_valid_veth_mtu(nla_get_u32(tb[IFLA_MTU])))
359 return -EINVAL;
360 }
361 return 0;
362}
363
364static struct rtnl_link_ops veth_link_ops;
365
366static int veth_newlink(struct net *src_net, struct net_device *dev,
367 struct nlattr *tb[], struct nlattr *data[])
368{
369 int err;
370 struct net_device *peer;
371 struct veth_priv *priv;
372 char ifname[IFNAMSIZ];
373 struct nlattr *peer_tb[IFLA_MAX + 1], **tbp;
374 unsigned char name_assign_type;
375 struct ifinfomsg *ifmp;
376 struct net *net;
377
378
379
380
381 if (data != NULL && data[VETH_INFO_PEER] != NULL) {
382 struct nlattr *nla_peer;
383
384 nla_peer = data[VETH_INFO_PEER];
385 ifmp = nla_data(nla_peer);
386 err = rtnl_nla_parse_ifla(peer_tb,
387 nla_data(nla_peer) + sizeof(struct ifinfomsg),
388 nla_len(nla_peer) - sizeof(struct ifinfomsg));
389 if (err < 0)
390 return err;
391
392 err = veth_validate(peer_tb, NULL);
393 if (err < 0)
394 return err;
395
396 tbp = peer_tb;
397 } else {
398 ifmp = NULL;
399 tbp = tb;
400 }
401
402 if (tbp[IFLA_IFNAME]) {
403 nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
404 name_assign_type = NET_NAME_USER;
405 } else {
406 snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
407 name_assign_type = NET_NAME_ENUM;
408 }
409
410 net = rtnl_link_get_net(src_net, tbp);
411 if (IS_ERR(net))
412 return PTR_ERR(net);
413
414 peer = rtnl_create_link(net, ifname, name_assign_type,
415 &veth_link_ops, tbp);
416 if (IS_ERR(peer)) {
417 put_net(net);
418 return PTR_ERR(peer);
419 }
420
421 if (tbp[IFLA_ADDRESS] == NULL)
422 eth_hw_addr_random(peer);
423
424 if (ifmp && (dev->ifindex != 0))
425 peer->ifindex = ifmp->ifi_index;
426
427 err = register_netdevice(peer);
428 put_net(net);
429 net = NULL;
430 if (err < 0)
431 goto err_register_peer;
432
433 netif_carrier_off(peer);
434
435 err = rtnl_configure_link(peer, ifmp);
436 if (err < 0)
437 goto err_configure_peer;
438
439
440
441
442
443
444
445
446 if (tb[IFLA_ADDRESS] == NULL)
447 eth_hw_addr_random(dev);
448
449 if (tb[IFLA_IFNAME])
450 nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
451 else
452 snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
453
454 err = register_netdevice(dev);
455 if (err < 0)
456 goto err_register_dev;
457
458 netif_carrier_off(dev);
459
460
461
462
463
464 priv = netdev_priv(dev);
465 rcu_assign_pointer(priv->peer, peer);
466
467 priv = netdev_priv(peer);
468 rcu_assign_pointer(priv->peer, dev);
469 return 0;
470
471err_register_dev:
472
473err_configure_peer:
474 unregister_netdevice(peer);
475 return err;
476
477err_register_peer:
478 free_netdev(peer);
479 return err;
480}
481
482static void veth_dellink(struct net_device *dev, struct list_head *head)
483{
484 struct veth_priv *priv;
485 struct net_device *peer;
486
487 priv = netdev_priv(dev);
488 peer = rtnl_dereference(priv->peer);
489
490
491
492
493
494 RCU_INIT_POINTER(priv->peer, NULL);
495 unregister_netdevice_queue(dev, head);
496
497 if (peer) {
498 priv = netdev_priv(peer);
499 RCU_INIT_POINTER(priv->peer, NULL);
500 unregister_netdevice_queue(peer, head);
501 }
502}
503
504static const struct nla_policy veth_policy[VETH_INFO_MAX + 1] = {
505 [VETH_INFO_PEER] = { .len = sizeof(struct ifinfomsg) },
506};
507
508static struct net *veth_get_link_net(const struct net_device *dev)
509{
510 struct veth_priv *priv = netdev_priv(dev);
511 struct net_device *peer = rtnl_dereference(priv->peer);
512
513 return peer ? dev_net(peer) : dev_net(dev);
514}
515
516static struct rtnl_link_ops veth_link_ops = {
517 .kind = DRV_NAME,
518 .priv_size = sizeof(struct veth_priv),
519 .setup = veth_setup,
520 .validate = veth_validate,
521 .newlink = veth_newlink,
522 .dellink = veth_dellink,
523 .policy = veth_policy,
524 .maxtype = VETH_INFO_MAX,
525 .get_link_net = veth_get_link_net,
526};
527
528
529
530
531
532static __init int veth_init(void)
533{
534 return rtnl_link_register(&veth_link_ops);
535}
536
537static __exit void veth_exit(void)
538{
539 rtnl_link_unregister(&veth_link_ops);
540}
541
542module_init(veth_init);
543module_exit(veth_exit);
544
545MODULE_DESCRIPTION("Virtual Ethernet Tunnel");
546MODULE_LICENSE("GPL v2");
547MODULE_ALIAS_RTNL_LINK(DRV_NAME);
548
