xref: /linux/drivers/net/veth.c (revision 0c93ea4064a209cdc36de8a9a3003d43d08f46f7)
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_close(struct net_device *dev)
243 {
244 	struct veth_priv *priv = netdev_priv(dev);
245 
246 	netif_carrier_off(dev);
247 	netif_carrier_off(priv->peer);
248 
249 	return 0;
250 }
251 
252 static int veth_dev_init(struct net_device *dev)
253 {
254 	struct veth_net_stats *stats;
255 	struct veth_priv *priv;
256 
257 	stats = alloc_percpu(struct veth_net_stats);
258 	if (stats == NULL)
259 		return -ENOMEM;
260 
261 	priv = netdev_priv(dev);
262 	priv->stats = stats;
263 	return 0;
264 }
265 
266 static void veth_dev_free(struct net_device *dev)
267 {
268 	struct veth_priv *priv;
269 
270 	priv = netdev_priv(dev);
271 	free_percpu(priv->stats);
272 	free_netdev(dev);
273 }
274 
275 static const struct net_device_ops veth_netdev_ops = {
276 	.ndo_init            = veth_dev_init,
277 	.ndo_open            = veth_open,
278 	.ndo_stop            = veth_close,
279 	.ndo_start_xmit      = veth_xmit,
280 	.ndo_get_stats       = veth_get_stats,
281 	.ndo_set_mac_address = eth_mac_addr,
282 };
283 
284 static void veth_setup(struct net_device *dev)
285 {
286 	ether_setup(dev);
287 
288 	dev->netdev_ops = &veth_netdev_ops;
289 	dev->ethtool_ops = &veth_ethtool_ops;
290 	dev->features |= NETIF_F_LLTX;
291 	dev->destructor = veth_dev_free;
292 }
293 
294 /*
295  * netlink interface
296  */
297 
298 static int veth_validate(struct nlattr *tb[], struct nlattr *data[])
299 {
300 	if (tb[IFLA_ADDRESS]) {
301 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
302 			return -EINVAL;
303 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
304 			return -EADDRNOTAVAIL;
305 	}
306 	return 0;
307 }
308 
309 static struct rtnl_link_ops veth_link_ops;
310 
311 static int veth_newlink(struct net_device *dev,
312 			 struct nlattr *tb[], struct nlattr *data[])
313 {
314 	int err;
315 	struct net_device *peer;
316 	struct veth_priv *priv;
317 	char ifname[IFNAMSIZ];
318 	struct nlattr *peer_tb[IFLA_MAX + 1], **tbp;
319 
320 	/*
321 	 * create and register peer first
322 	 *
323 	 * struct ifinfomsg is at the head of VETH_INFO_PEER, but we
324 	 * skip it since no info from it is useful yet
325 	 */
326 
327 	if (data != NULL && data[VETH_INFO_PEER] != NULL) {
328 		struct nlattr *nla_peer;
329 
330 		nla_peer = data[VETH_INFO_PEER];
331 		err = nla_parse(peer_tb, IFLA_MAX,
332 				nla_data(nla_peer) + sizeof(struct ifinfomsg),
333 				nla_len(nla_peer) - sizeof(struct ifinfomsg),
334 				ifla_policy);
335 		if (err < 0)
336 			return err;
337 
338 		err = veth_validate(peer_tb, NULL);
339 		if (err < 0)
340 			return err;
341 
342 		tbp = peer_tb;
343 	} else
344 		tbp = tb;
345 
346 	if (tbp[IFLA_IFNAME])
347 		nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
348 	else
349 		snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
350 
351 	peer = rtnl_create_link(dev_net(dev), ifname, &veth_link_ops, tbp);
352 	if (IS_ERR(peer))
353 		return PTR_ERR(peer);
354 
355 	if (tbp[IFLA_ADDRESS] == NULL)
356 		random_ether_addr(peer->dev_addr);
357 
358 	err = register_netdevice(peer);
359 	if (err < 0)
360 		goto err_register_peer;
361 
362 	netif_carrier_off(peer);
363 
364 	/*
365 	 * register dev last
366 	 *
367 	 * note, that since we've registered new device the dev's name
368 	 * should be re-allocated
369 	 */
370 
371 	if (tb[IFLA_ADDRESS] == NULL)
372 		random_ether_addr(dev->dev_addr);
373 
374 	if (tb[IFLA_IFNAME])
375 		nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
376 	else
377 		snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
378 
379 	if (strchr(dev->name, '%')) {
380 		err = dev_alloc_name(dev, dev->name);
381 		if (err < 0)
382 			goto err_alloc_name;
383 	}
384 
385 	err = register_netdevice(dev);
386 	if (err < 0)
387 		goto err_register_dev;
388 
389 	netif_carrier_off(dev);
390 
391 	/*
392 	 * tie the deviced together
393 	 */
394 
395 	priv = netdev_priv(dev);
396 	priv->peer = peer;
397 
398 	priv = netdev_priv(peer);
399 	priv->peer = dev;
400 	return 0;
401 
402 err_register_dev:
403 	/* nothing to do */
404 err_alloc_name:
405 	unregister_netdevice(peer);
406 	return err;
407 
408 err_register_peer:
409 	free_netdev(peer);
410 	return err;
411 }
412 
413 static void veth_dellink(struct net_device *dev)
414 {
415 	struct veth_priv *priv;
416 	struct net_device *peer;
417 
418 	priv = netdev_priv(dev);
419 	peer = priv->peer;
420 
421 	unregister_netdevice(dev);
422 	unregister_netdevice(peer);
423 }
424 
425 static const struct nla_policy veth_policy[VETH_INFO_MAX + 1];
426 
427 static struct rtnl_link_ops veth_link_ops = {
428 	.kind		= DRV_NAME,
429 	.priv_size	= sizeof(struct veth_priv),
430 	.setup		= veth_setup,
431 	.validate	= veth_validate,
432 	.newlink	= veth_newlink,
433 	.dellink	= veth_dellink,
434 	.policy		= veth_policy,
435 	.maxtype	= VETH_INFO_MAX,
436 };
437 
438 /*
439  * init/fini
440  */
441 
442 static __init int veth_init(void)
443 {
444 	return rtnl_link_register(&veth_link_ops);
445 }
446 
447 static __exit void veth_exit(void)
448 {
449 	rtnl_link_unregister(&veth_link_ops);
450 }
451 
452 module_init(veth_init);
453 module_exit(veth_exit);
454 
455 MODULE_DESCRIPTION("Virtual Ethernet Tunnel");
456 MODULE_LICENSE("GPL v2");
457 MODULE_ALIAS_RTNL_LINK(DRV_NAME);
458