xref: /linux/drivers/net/veth.c (revision b233b28eac0cc37d07c2d007ea08c86c778c5af4) 
1 /*
2  *  drivers/net/veth.c
3  *
4  *  Copyright (C) 2007 OpenVZ http://openvz.org, SWsoft Inc
5  *
6  * Author: Pavel Emelianov <xemul@openvz.org>
7  * Ethtool interface from: Eric W. Biederman <ebiederm@xmission.com>
8  *
9  */
10 
11 #include <linux/netdevice.h>
12 #include <linux/ethtool.h>
13 #include <linux/etherdevice.h>
14 
15 #include <net/dst.h>
16 #include <net/xfrm.h>
17 #include <linux/veth.h>
18 
19 #define DRV_NAME	"veth"
20 #define DRV_VERSION	"1.0"
21 
22 struct veth_net_stats {
23 	unsigned long	rx_packets;
24 	unsigned long	tx_packets;
25 	unsigned long	rx_bytes;
26 	unsigned long	tx_bytes;
27 	unsigned long	tx_dropped;
28 };
29 
30 struct veth_priv {
31 	struct net_device *peer;
32 	struct veth_net_stats *stats;
33 	unsigned ip_summed;
34 };
35 
36 /*
37  * ethtool interface
38  */
39 
40 static struct {
41 	const char string[ETH_GSTRING_LEN];
42 } ethtool_stats_keys[] = {
43 	{ "peer_ifindex" },
44 };
45 
46 static int veth_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
47 {
48 	cmd->supported		= 0;
49 	cmd->advertising	= 0;
50 	cmd->speed		= SPEED_10000;
51 	cmd->duplex		= DUPLEX_FULL;
52 	cmd->port		= PORT_TP;
53 	cmd->phy_address	= 0;
54 	cmd->transceiver	= XCVR_INTERNAL;
55 	cmd->autoneg		= AUTONEG_DISABLE;
56 	cmd->maxtxpkt		= 0;
57 	cmd->maxrxpkt		= 0;
58 	return 0;
59 }
60 
61 static void veth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
62 {
63 	strcpy(info->driver, DRV_NAME);
64 	strcpy(info->version, DRV_VERSION);
65 	strcpy(info->fw_version, "N/A");
66 }
67 
68 static void veth_get_strings(struct net_device *dev, u32 stringset, u8 *buf)
69 {
70 	switch(stringset) {
71 	case ETH_SS_STATS:
72 		memcpy(buf, &ethtool_stats_keys, sizeof(ethtool_stats_keys));
73 		break;
74 	}
75 }
76 
77 static int veth_get_sset_count(struct net_device *dev, int sset)
78 {
79 	switch (sset) {
80 	case ETH_SS_STATS:
81 		return ARRAY_SIZE(ethtool_stats_keys);
82 	default:
83 		return -EOPNOTSUPP;
84 	}
85 }
86 
87 static void veth_get_ethtool_stats(struct net_device *dev,
88 		struct ethtool_stats *stats, u64 *data)
89 {
90 	struct veth_priv *priv;
91 
92 	priv = netdev_priv(dev);
93 	data[0] = priv->peer->ifindex;
94 }
95 
96 static u32 veth_get_rx_csum(struct net_device *dev)
97 {
98 	struct veth_priv *priv;
99 
100 	priv = netdev_priv(dev);
101 	return priv->ip_summed == CHECKSUM_UNNECESSARY;
102 }
103 
104 static int veth_set_rx_csum(struct net_device *dev, u32 data)
105 {
106 	struct veth_priv *priv;
107 
108 	priv = netdev_priv(dev);
109 	priv->ip_summed = data ? CHECKSUM_UNNECESSARY : CHECKSUM_NONE;
110 	return 0;
111 }
112 
113 static u32 veth_get_tx_csum(struct net_device *dev)
114 {
115 	return (dev->features & NETIF_F_NO_CSUM) != 0;
116 }
117 
118 static int veth_set_tx_csum(struct net_device *dev, u32 data)
119 {
120 	if (data)
121 		dev->features |= NETIF_F_NO_CSUM;
122 	else
123 		dev->features &= ~NETIF_F_NO_CSUM;
124 	return 0;
125 }
126 
127 static struct ethtool_ops veth_ethtool_ops = {
128 	.get_settings		= veth_get_settings,
129 	.get_drvinfo		= veth_get_drvinfo,
130 	.get_link		= ethtool_op_get_link,
131 	.get_rx_csum		= veth_get_rx_csum,
132 	.set_rx_csum		= veth_set_rx_csum,
133 	.get_tx_csum		= veth_get_tx_csum,
134 	.set_tx_csum		= veth_set_tx_csum,
135 	.get_sg			= ethtool_op_get_sg,
136 	.set_sg			= ethtool_op_set_sg,
137 	.get_strings		= veth_get_strings,
138 	.get_sset_count		= veth_get_sset_count,
139 	.get_ethtool_stats	= veth_get_ethtool_stats,
140 };
141 
142 /*
143  * xmit
144  */
145 
146 static int veth_xmit(struct sk_buff *skb, struct net_device *dev)
147 {
148 	struct net_device *rcv = NULL;
149 	struct veth_priv *priv, *rcv_priv;
150 	struct veth_net_stats *stats;
151 	int length, cpu;
152 
153 	skb_orphan(skb);
154 
155 	priv = netdev_priv(dev);
156 	rcv = priv->peer;
157 	rcv_priv = netdev_priv(rcv);
158 
159 	cpu = smp_processor_id();
160 	stats = per_cpu_ptr(priv->stats, cpu);
161 
162 	if (!(rcv->flags & IFF_UP))
163 		goto outf;
164 
165 	skb->pkt_type = PACKET_HOST;
166 	skb->protocol = eth_type_trans(skb, rcv);
167 	if (dev->features & NETIF_F_NO_CSUM)
168 		skb->ip_summed = rcv_priv->ip_summed;
169 
170 	dst_release(skb->dst);
171 	skb->dst = NULL;
172 	skb->mark = 0;
173 	secpath_reset(skb);
174 	nf_reset(skb);
175 
176 	length = skb->len;
177 
178 	stats->tx_bytes += length;
179 	stats->tx_packets++;
180 
181 	stats = per_cpu_ptr(rcv_priv->stats, cpu);
182 	stats->rx_bytes += length;
183 	stats->rx_packets++;
184 
185 	netif_rx(skb);
186 	return 0;
187 
188 outf:
189 	kfree_skb(skb);
190 	stats->tx_dropped++;
191 	return 0;
192 }
193 
194 /*
195  * general routines
196  */
197 
198 static struct net_device_stats *veth_get_stats(struct net_device *dev)
199 {
200 	struct veth_priv *priv;
201 	struct net_device_stats *dev_stats;
202 	int cpu;
203 	struct veth_net_stats *stats;
204 
205 	priv = netdev_priv(dev);
206 	dev_stats = &dev->stats;
207 
208 	dev_stats->rx_packets = 0;
209 	dev_stats->tx_packets = 0;
210 	dev_stats->rx_bytes = 0;
211 	dev_stats->tx_bytes = 0;
212 	dev_stats->tx_dropped = 0;
213 
214 	for_each_online_cpu(cpu) {
215 		stats = per_cpu_ptr(priv->stats, cpu);
216 
217 		dev_stats->rx_packets += stats->rx_packets;
218 		dev_stats->tx_packets += stats->tx_packets;
219 		dev_stats->rx_bytes += stats->rx_bytes;
220 		dev_stats->tx_bytes += stats->tx_bytes;
221 		dev_stats->tx_dropped += stats->tx_dropped;
222 	}
223 
224 	return dev_stats;
225 }
226 
227 static int veth_open(struct net_device *dev)
228 {
229 	struct veth_priv *priv;
230 
231 	priv = netdev_priv(dev);
232 	if (priv->peer == NULL)
233 		return -ENOTCONN;
234 
235 	if (priv->peer->flags & IFF_UP) {
236 		netif_carrier_on(dev);
237 		netif_carrier_on(priv->peer);
238 	}
239 	return 0;
240 }
241 
242 static int veth_dev_init(struct net_device *dev)
243 {
244 	struct veth_net_stats *stats;
245 	struct veth_priv *priv;
246 
247 	stats = alloc_percpu(struct veth_net_stats);
248 	if (stats == NULL)
249 		return -ENOMEM;
250 
251 	priv = netdev_priv(dev);
252 	priv->stats = stats;
253 	return 0;
254 }
255 
256 static void veth_dev_free(struct net_device *dev)
257 {
258 	struct veth_priv *priv;
259 
260 	priv = netdev_priv(dev);
261 	free_percpu(priv->stats);
262 	free_netdev(dev);
263 }
264 
265 static const struct net_device_ops veth_netdev_ops = {
266 	.ndo_init	= veth_dev_init,
267 	.ndo_open	= veth_open,
268 	.ndo_start_xmit = veth_xmit,
269 	.ndo_get_stats	= veth_get_stats,
270 };
271 
272 static void veth_setup(struct net_device *dev)
273 {
274 	ether_setup(dev);
275 
276 	dev->netdev_ops = &veth_netdev_ops;
277 	dev->ethtool_ops = &veth_ethtool_ops;
278 	dev->features |= NETIF_F_LLTX;
279 	dev->destructor = veth_dev_free;
280 }
281 
282 static void veth_change_state(struct net_device *dev)
283 {
284 	struct net_device *peer;
285 	struct veth_priv *priv;
286 
287 	priv = netdev_priv(dev);
288 	peer = priv->peer;
289 
290 	if (netif_carrier_ok(peer)) {
291 		if (!netif_carrier_ok(dev))
292 			netif_carrier_on(dev);
293 	} else {
294 		if (netif_carrier_ok(dev))
295 			netif_carrier_off(dev);
296 	}
297 }
298 
299 static int veth_device_event(struct notifier_block *unused,
300 			     unsigned long event, void *ptr)
301 {
302 	struct net_device *dev = ptr;
303 
304 	if (dev->netdev_ops->ndo_open != veth_open)
305 		goto out;
306 
307 	switch (event) {
308 	case NETDEV_CHANGE:
309 		veth_change_state(dev);
310 		break;
311 	}
312 out:
313 	return NOTIFY_DONE;
314 }
315 
316 static struct notifier_block veth_notifier_block __read_mostly = {
317 	.notifier_call	= veth_device_event,
318 };
319 
320 /*
321  * netlink interface
322  */
323 
324 static 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 	return 0;
333 }
334 
335 static struct rtnl_link_ops veth_link_ops;
336 
337 static int veth_newlink(struct net_device *dev,
338 			 struct nlattr *tb[], struct nlattr *data[])
339 {
340 	int err;
341 	struct net_device *peer;
342 	struct veth_priv *priv;
343 	char ifname[IFNAMSIZ];
344 	struct nlattr *peer_tb[IFLA_MAX + 1], **tbp;
345 
346 	/*
347 	 * create and register peer first
348 	 *
349 	 * struct ifinfomsg is at the head of VETH_INFO_PEER, but we
350 	 * skip it since no info from it is useful yet
351 	 */
352 
353 	if (data != NULL && data[VETH_INFO_PEER] != NULL) {
354 		struct nlattr *nla_peer;
355 
356 		nla_peer = data[VETH_INFO_PEER];
357 		err = nla_parse(peer_tb, IFLA_MAX,
358 				nla_data(nla_peer) + sizeof(struct ifinfomsg),
359 				nla_len(nla_peer) - sizeof(struct ifinfomsg),
360 				ifla_policy);
361 		if (err < 0)
362 			return err;
363 
364 		err = veth_validate(peer_tb, NULL);
365 		if (err < 0)
366 			return err;
367 
368 		tbp = peer_tb;
369 	} else
370 		tbp = tb;
371 
372 	if (tbp[IFLA_IFNAME])
373 		nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
374 	else
375 		snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
376 
377 	peer = rtnl_create_link(dev_net(dev), ifname, &veth_link_ops, tbp);
378 	if (IS_ERR(peer))
379 		return PTR_ERR(peer);
380 
381 	if (tbp[IFLA_ADDRESS] == NULL)
382 		random_ether_addr(peer->dev_addr);
383 
384 	err = register_netdevice(peer);
385 	if (err < 0)
386 		goto err_register_peer;
387 
388 	netif_carrier_off(peer);
389 
390 	/*
391 	 * register dev last
392 	 *
393 	 * note, that since we've registered new device the dev's name
394 	 * should be re-allocated
395 	 */
396 
397 	if (tb[IFLA_ADDRESS] == NULL)
398 		random_ether_addr(dev->dev_addr);
399 
400 	if (tb[IFLA_IFNAME])
401 		nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
402 	else
403 		snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
404 
405 	if (strchr(dev->name, '%')) {
406 		err = dev_alloc_name(dev, dev->name);
407 		if (err < 0)
408 			goto err_alloc_name;
409 	}
410 
411 	err = register_netdevice(dev);
412 	if (err < 0)
413 		goto err_register_dev;
414 
415 	netif_carrier_off(dev);
416 
417 	/*
418 	 * tie the deviced together
419 	 */
420 
421 	priv = netdev_priv(dev);
422 	priv->peer = peer;
423 
424 	priv = netdev_priv(peer);
425 	priv->peer = dev;
426 	return 0;
427 
428 err_register_dev:
429 	/* nothing to do */
430 err_alloc_name:
431 	unregister_netdevice(peer);
432 	return err;
433 
434 err_register_peer:
435 	free_netdev(peer);
436 	return err;
437 }
438 
439 static void veth_dellink(struct net_device *dev)
440 {
441 	struct veth_priv *priv;
442 	struct net_device *peer;
443 
444 	priv = netdev_priv(dev);
445 	peer = priv->peer;
446 
447 	unregister_netdevice(dev);
448 	unregister_netdevice(peer);
449 }
450 
451 static const struct nla_policy veth_policy[VETH_INFO_MAX + 1];
452 
453 static struct rtnl_link_ops veth_link_ops = {
454 	.kind		= DRV_NAME,
455 	.priv_size	= sizeof(struct veth_priv),
456 	.setup		= veth_setup,
457 	.validate	= veth_validate,
458 	.newlink	= veth_newlink,
459 	.dellink	= veth_dellink,
460 	.policy		= veth_policy,
461 	.maxtype	= VETH_INFO_MAX,
462 };
463 
464 /*
465  * init/fini
466  */
467 
468 static __init int veth_init(void)
469 {
470 	register_netdevice_notifier(&veth_notifier_block);
471 	return rtnl_link_register(&veth_link_ops);
472 }
473 
474 static __exit void veth_exit(void)
475 {
476 	rtnl_link_unregister(&veth_link_ops);
477 	unregister_netdevice_notifier(&veth_notifier_block);
478 }
479 
480 module_init(veth_init);
481 module_exit(veth_exit);
482 
483 MODULE_DESCRIPTION("Virtual Ethernet Tunnel");
484 MODULE_LICENSE("GPL v2");
485 MODULE_ALIAS_RTNL_LINK(DRV_NAME);
486