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/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
 
 
 
 26struct pcpu_vstats {
 27	u64			packets;
 28	u64			bytes;
 29	struct u64_stats_sync	syncp;
 30};
 31
 32struct veth_priv {
 33	struct net_device __rcu	*peer;
 34	atomic64_t		dropped;
 35	unsigned		requested_headroom;
 36};
 37
 38/*
 39 * ethtool interface
 40 */
 41
 42static struct {
 43	const char string[ETH_GSTRING_LEN];
 44} ethtool_stats_keys[] = {
 45	{ "peer_ifindex" },
 46};
 47
 48static int veth_get_link_ksettings(struct net_device *dev,
 49				   struct ethtool_link_ksettings *cmd)
 50{
 51	cmd->base.speed		= SPEED_10000;
 52	cmd->base.duplex	= DUPLEX_FULL;
 53	cmd->base.port		= PORT_TP;
 54	cmd->base.autoneg	= AUTONEG_DISABLE;
 
 
 
 
 
 
 55	return 0;
 56}
 57
 58static void veth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
 59{
 60	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
 61	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
 62}
 63
 64static void veth_get_strings(struct net_device *dev, u32 stringset, u8 *buf)
 65{
 66	switch(stringset) {
 67	case ETH_SS_STATS:
 68		memcpy(buf, &ethtool_stats_keys, sizeof(ethtool_stats_keys));
 69		break;
 70	}
 71}
 72
 73static int veth_get_sset_count(struct net_device *dev, int sset)
 74{
 75	switch (sset) {
 76	case ETH_SS_STATS:
 77		return ARRAY_SIZE(ethtool_stats_keys);
 78	default:
 79		return -EOPNOTSUPP;
 80	}
 81}
 82
 83static void veth_get_ethtool_stats(struct net_device *dev,
 84		struct ethtool_stats *stats, u64 *data)
 85{
 86	struct veth_priv *priv = netdev_priv(dev);
 87	struct net_device *peer = rtnl_dereference(priv->peer);
 88
 89	data[0] = peer ? peer->ifindex : 0;
 90}
 91
 92static const struct ethtool_ops veth_ethtool_ops = {
 
 93	.get_drvinfo		= veth_get_drvinfo,
 94	.get_link		= ethtool_op_get_link,
 95	.get_strings		= veth_get_strings,
 96	.get_sset_count		= veth_get_sset_count,
 97	.get_ethtool_stats	= veth_get_ethtool_stats,
 98	.get_link_ksettings	= veth_get_link_ksettings,
 99};
100
101static netdev_tx_t veth_xmit(struct sk_buff *skb, struct net_device *dev)
102{
103	struct veth_priv *priv = netdev_priv(dev);
104	struct net_device *rcv;
105	int length = skb->len;
106
107	rcu_read_lock();
108	rcv = rcu_dereference(priv->peer);
109	if (unlikely(!rcv)) {
110		kfree_skb(skb);
111		goto drop;
112	}
113
114	if (likely(dev_forward_skb(rcv, skb) == NET_RX_SUCCESS)) {
115		struct pcpu_vstats *stats = this_cpu_ptr(dev->vstats);
116
117		u64_stats_update_begin(&stats->syncp);
118		stats->bytes += length;
119		stats->packets++;
120		u64_stats_update_end(&stats->syncp);
121	} else {
122drop:
123		atomic64_inc(&priv->dropped);
124	}
125	rcu_read_unlock();
126	return NETDEV_TX_OK;
127}
128
129/*
130 * general routines
131 */
132
133static u64 veth_stats_one(struct pcpu_vstats *result, struct net_device *dev)
134{
135	struct veth_priv *priv = netdev_priv(dev);
136	int cpu;
137
138	result->packets = 0;
139	result->bytes = 0;
140	for_each_possible_cpu(cpu) {
141		struct pcpu_vstats *stats = per_cpu_ptr(dev->vstats, cpu);
142		u64 packets, bytes;
143		unsigned int start;
144
145		do {
146			start = u64_stats_fetch_begin_irq(&stats->syncp);
147			packets = stats->packets;
148			bytes = stats->bytes;
149		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
150		result->packets += packets;
151		result->bytes += bytes;
152	}
153	return atomic64_read(&priv->dropped);
154}
155
156static void veth_get_stats64(struct net_device *dev,
157			     struct rtnl_link_stats64 *tot)
158{
159	struct veth_priv *priv = netdev_priv(dev);
160	struct net_device *peer;
161	struct pcpu_vstats one;
162
163	tot->tx_dropped = veth_stats_one(&one, dev);
164	tot->tx_bytes = one.bytes;
165	tot->tx_packets = one.packets;
166
167	rcu_read_lock();
168	peer = rcu_dereference(priv->peer);
169	if (peer) {
170		tot->rx_dropped = veth_stats_one(&one, peer);
171		tot->rx_bytes = one.bytes;
172		tot->rx_packets = one.packets;
173	}
174	rcu_read_unlock();
 
 
175}
176
177/* fake multicast ability */
178static void veth_set_multicast_list(struct net_device *dev)
179{
180}
181
182static int veth_open(struct net_device *dev)
183{
184	struct veth_priv *priv = netdev_priv(dev);
185	struct net_device *peer = rtnl_dereference(priv->peer);
186
187	if (!peer)
188		return -ENOTCONN;
189
190	if (peer->flags & IFF_UP) {
191		netif_carrier_on(dev);
192		netif_carrier_on(peer);
193	}
194	return 0;
195}
196
197static int veth_close(struct net_device *dev)
198{
199	struct veth_priv *priv = netdev_priv(dev);
200	struct net_device *peer = rtnl_dereference(priv->peer);
201
202	netif_carrier_off(dev);
203	if (peer)
204		netif_carrier_off(peer);
205
206	return 0;
207}
208
209static int is_valid_veth_mtu(int mtu)
210{
211	return mtu >= ETH_MIN_MTU && mtu <= ETH_MAX_MTU;
 
 
 
 
 
 
 
 
212}
213
214static int veth_dev_init(struct net_device *dev)
215{
216	dev->vstats = netdev_alloc_pcpu_stats(struct pcpu_vstats);
217	if (!dev->vstats)
218		return -ENOMEM;
219	return 0;
220}
221
222static void veth_dev_free(struct net_device *dev)
223{
224	free_percpu(dev->vstats);
 
225}
226
227#ifdef CONFIG_NET_POLL_CONTROLLER
228static void veth_poll_controller(struct net_device *dev)
229{
230	/* veth only receives frames when its peer sends one
231	 * Since it's a synchronous operation, we are guaranteed
232	 * never to have pending data when we poll for it so
233	 * there is nothing to do here.
234	 *
235	 * We need this though so netpoll recognizes us as an interface that
236	 * supports polling, which enables bridge devices in virt setups to
237	 * still use netconsole
238	 */
239}
240#endif	/* CONFIG_NET_POLL_CONTROLLER */
241
242static int veth_get_iflink(const struct net_device *dev)
243{
244	struct veth_priv *priv = netdev_priv(dev);
245	struct net_device *peer;
246	int iflink;
247
248	rcu_read_lock();
249	peer = rcu_dereference(priv->peer);
250	iflink = peer ? peer->ifindex : 0;
251	rcu_read_unlock();
252
253	return iflink;
254}
255
256static void veth_set_rx_headroom(struct net_device *dev, int new_hr)
257{
258	struct veth_priv *peer_priv, *priv = netdev_priv(dev);
259	struct net_device *peer;
260
261	if (new_hr < 0)
262		new_hr = 0;
263
264	rcu_read_lock();
265	peer = rcu_dereference(priv->peer);
266	if (unlikely(!peer))
267		goto out;
268
269	peer_priv = netdev_priv(peer);
270	priv->requested_headroom = new_hr;
271	new_hr = max(priv->requested_headroom, peer_priv->requested_headroom);
272	dev->needed_headroom = new_hr;
273	peer->needed_headroom = new_hr;
274
275out:
276	rcu_read_unlock();
277}
278
279static const struct net_device_ops veth_netdev_ops = {
280	.ndo_init            = veth_dev_init,
281	.ndo_open            = veth_open,
282	.ndo_stop            = veth_close,
283	.ndo_start_xmit      = veth_xmit,
 
284	.ndo_get_stats64     = veth_get_stats64,
285	.ndo_set_rx_mode     = veth_set_multicast_list,
286	.ndo_set_mac_address = eth_mac_addr,
287#ifdef CONFIG_NET_POLL_CONTROLLER
288	.ndo_poll_controller	= veth_poll_controller,
289#endif
290	.ndo_get_iflink		= veth_get_iflink,
291	.ndo_features_check	= passthru_features_check,
292	.ndo_set_rx_headroom	= veth_set_rx_headroom,
293};
294
295#define VETH_FEATURES (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HW_CSUM | \
296		       NETIF_F_RXCSUM | NETIF_F_SCTP_CRC | NETIF_F_HIGHDMA | \
297		       NETIF_F_GSO_SOFTWARE | NETIF_F_GSO_ENCAP_ALL | \
 
298		       NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX | \
299		       NETIF_F_HW_VLAN_STAG_TX | NETIF_F_HW_VLAN_STAG_RX )
300
301static void veth_setup(struct net_device *dev)
302{
303	ether_setup(dev);
304
305	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
306	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
307	dev->priv_flags |= IFF_NO_QUEUE;
308	dev->priv_flags |= IFF_PHONY_HEADROOM;
309
310	dev->netdev_ops = &veth_netdev_ops;
311	dev->ethtool_ops = &veth_ethtool_ops;
312	dev->features |= NETIF_F_LLTX;
313	dev->features |= VETH_FEATURES;
314	dev->vlan_features = dev->features &
315			     ~(NETIF_F_HW_VLAN_CTAG_TX |
316			       NETIF_F_HW_VLAN_STAG_TX |
317			       NETIF_F_HW_VLAN_CTAG_RX |
318			       NETIF_F_HW_VLAN_STAG_RX);
319	dev->needs_free_netdev = true;
320	dev->priv_destructor = veth_dev_free;
321	dev->max_mtu = ETH_MAX_MTU;
322
323	dev->hw_features = VETH_FEATURES;
324	dev->hw_enc_features = VETH_FEATURES;
325	dev->mpls_features = NETIF_F_HW_CSUM | NETIF_F_GSO_SOFTWARE;
326}
327
328/*
329 * netlink interface
330 */
331
332static int veth_validate(struct nlattr *tb[], struct nlattr *data[],
333			 struct netlink_ext_ack *extack)
334{
335	if (tb[IFLA_ADDRESS]) {
336		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
337			return -EINVAL;
338		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
339			return -EADDRNOTAVAIL;
340	}
341	if (tb[IFLA_MTU]) {
342		if (!is_valid_veth_mtu(nla_get_u32(tb[IFLA_MTU])))
343			return -EINVAL;
344	}
345	return 0;
346}
347
348static struct rtnl_link_ops veth_link_ops;
349
350static int veth_newlink(struct net *src_net, struct net_device *dev,
351			struct nlattr *tb[], struct nlattr *data[],
352			struct netlink_ext_ack *extack)
353{
354	int err;
355	struct net_device *peer;
356	struct veth_priv *priv;
357	char ifname[IFNAMSIZ];
358	struct nlattr *peer_tb[IFLA_MAX + 1], **tbp;
359	unsigned char name_assign_type;
360	struct ifinfomsg *ifmp;
361	struct net *net;
362
363	/*
364	 * create and register peer first
365	 */
366	if (data != NULL && data[VETH_INFO_PEER] != NULL) {
367		struct nlattr *nla_peer;
368
369		nla_peer = data[VETH_INFO_PEER];
370		ifmp = nla_data(nla_peer);
371		err = rtnl_nla_parse_ifla(peer_tb,
372					  nla_data(nla_peer) + sizeof(struct ifinfomsg),
373					  nla_len(nla_peer) - sizeof(struct ifinfomsg),
374					  NULL);
375		if (err < 0)
376			return err;
377
378		err = veth_validate(peer_tb, NULL, extack);
379		if (err < 0)
380			return err;
381
382		tbp = peer_tb;
383	} else {
384		ifmp = NULL;
385		tbp = tb;
386	}
387
388	if (ifmp && tbp[IFLA_IFNAME]) {
389		nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
390		name_assign_type = NET_NAME_USER;
391	} else {
392		snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
393		name_assign_type = NET_NAME_ENUM;
394	}
395
396	net = rtnl_link_get_net(src_net, tbp);
397	if (IS_ERR(net))
398		return PTR_ERR(net);
399
400	peer = rtnl_create_link(net, ifname, name_assign_type,
401				&veth_link_ops, tbp);
402	if (IS_ERR(peer)) {
403		put_net(net);
404		return PTR_ERR(peer);
405	}
406
407	if (!ifmp || !tbp[IFLA_ADDRESS])
408		eth_hw_addr_random(peer);
409
410	if (ifmp && (dev->ifindex != 0))
411		peer->ifindex = ifmp->ifi_index;
412
413	peer->gso_max_size = dev->gso_max_size;
414	peer->gso_max_segs = dev->gso_max_segs;
415
416	err = register_netdevice(peer);
417	put_net(net);
418	net = NULL;
419	if (err < 0)
420		goto err_register_peer;
421
422	netif_carrier_off(peer);
423
424	err = rtnl_configure_link(peer, ifmp);
425	if (err < 0)
426		goto err_configure_peer;
427
428	/*
429	 * register dev last
430	 *
431	 * note, that since we've registered new device the dev's name
432	 * should be re-allocated
433	 */
434
435	if (tb[IFLA_ADDRESS] == NULL)
436		eth_hw_addr_random(dev);
437
438	if (tb[IFLA_IFNAME])
439		nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
440	else
441		snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
442
443	err = register_netdevice(dev);
444	if (err < 0)
445		goto err_register_dev;
446
447	netif_carrier_off(dev);
448
449	/*
450	 * tie the deviced together
451	 */
452
453	priv = netdev_priv(dev);
454	rcu_assign_pointer(priv->peer, peer);
455
456	priv = netdev_priv(peer);
457	rcu_assign_pointer(priv->peer, dev);
458	return 0;
459
460err_register_dev:
461	/* nothing to do */
462err_configure_peer:
463	unregister_netdevice(peer);
464	return err;
465
466err_register_peer:
467	free_netdev(peer);
468	return err;
469}
470
471static void veth_dellink(struct net_device *dev, struct list_head *head)
472{
473	struct veth_priv *priv;
474	struct net_device *peer;
475
476	priv = netdev_priv(dev);
477	peer = rtnl_dereference(priv->peer);
478
479	/* Note : dellink() is called from default_device_exit_batch(),
480	 * before a rcu_synchronize() point. The devices are guaranteed
481	 * not being freed before one RCU grace period.
482	 */
483	RCU_INIT_POINTER(priv->peer, NULL);
484	unregister_netdevice_queue(dev, head);
485
486	if (peer) {
487		priv = netdev_priv(peer);
488		RCU_INIT_POINTER(priv->peer, NULL);
489		unregister_netdevice_queue(peer, head);
490	}
491}
492
493static const struct nla_policy veth_policy[VETH_INFO_MAX + 1] = {
494	[VETH_INFO_PEER]	= { .len = sizeof(struct ifinfomsg) },
495};
496
497static struct net *veth_get_link_net(const struct net_device *dev)
498{
499	struct veth_priv *priv = netdev_priv(dev);
500	struct net_device *peer = rtnl_dereference(priv->peer);
501
502	return peer ? dev_net(peer) : dev_net(dev);
503}
504
505static struct rtnl_link_ops veth_link_ops = {
506	.kind		= DRV_NAME,
507	.priv_size	= sizeof(struct veth_priv),
508	.setup		= veth_setup,
509	.validate	= veth_validate,
510	.newlink	= veth_newlink,
511	.dellink	= veth_dellink,
512	.policy		= veth_policy,
513	.maxtype	= VETH_INFO_MAX,
514	.get_link_net	= veth_get_link_net,
515};
516
517/*
518 * init/fini
519 */
520
521static __init int veth_init(void)
522{
523	return rtnl_link_register(&veth_link_ops);
524}
525
526static __exit void veth_exit(void)
527{
528	rtnl_link_unregister(&veth_link_ops);
529}
530
531module_init(veth_init);
532module_exit(veth_exit);
533
534MODULE_DESCRIPTION("Virtual Ethernet Tunnel");
535MODULE_LICENSE("GPL v2");
536MODULE_ALIAS_RTNL_LINK(DRV_NAME);

  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/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		/* Min L3 MTU */
 27#define MAX_MTU 65535		/* Max L3 MTU (arbitrary) */
 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 * ethtool interface
 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, &ethtool_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 * general routines
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/* fake multicast ability */
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	/* veth only receives frames when its peer sends one
250	 * Since it's a synchronous operation, we are guaranteed
251	 * never to have pending data when we poll for it so
252	 * there is nothing to do here.
253	 *
254	 * We need this though so netpoll recognizes us as an interface that
255	 * supports polling, which enables bridge devices in virt setups to
256	 * still use netconsole
257	 */
258}
259#endif	/* CONFIG_NET_POLL_CONTROLLER */
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_ALL_TSO |    \
316		       NETIF_F_HW_CSUM | NETIF_F_RXCSUM | NETIF_F_HIGHDMA | \
317		       NETIF_F_GSO_GRE | NETIF_F_GSO_UDP_TUNNEL |	    \
318		       NETIF_F_GSO_IPIP | NETIF_F_GSO_SIT | NETIF_F_UFO	|   \
319		       NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX | \
320		       NETIF_F_HW_VLAN_STAG_TX | NETIF_F_HW_VLAN_STAG_RX )
321
322static void veth_setup(struct net_device *dev)
323{
324	ether_setup(dev);
325
326	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
327	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
328	dev->priv_flags |= IFF_NO_QUEUE;
329	dev->priv_flags |= IFF_PHONY_HEADROOM;
330
331	dev->netdev_ops = &veth_netdev_ops;
332	dev->ethtool_ops = &veth_ethtool_ops;
333	dev->features |= NETIF_F_LLTX;
334	dev->features |= VETH_FEATURES;
335	dev->vlan_features = dev->features &
336			     ~(NETIF_F_HW_VLAN_CTAG_TX |
337			       NETIF_F_HW_VLAN_STAG_TX |
338			       NETIF_F_HW_VLAN_CTAG_RX |
339			       NETIF_F_HW_VLAN_STAG_RX);
340	dev->destructor = veth_dev_free;
 
 
341
342	dev->hw_features = VETH_FEATURES;
343	dev->hw_enc_features = VETH_FEATURES;
 
344}
345
346/*
347 * netlink interface
348 */
349
350static int veth_validate(struct nlattr *tb[], struct nlattr *data[])
 
351{
352	if (tb[IFLA_ADDRESS]) {
353		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
354			return -EINVAL;
355		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
356			return -EADDRNOTAVAIL;
357	}
358	if (tb[IFLA_MTU]) {
359		if (!is_valid_veth_mtu(nla_get_u32(tb[IFLA_MTU])))
360			return -EINVAL;
361	}
362	return 0;
363}
364
365static struct rtnl_link_ops veth_link_ops;
366
367static int veth_newlink(struct net *src_net, struct net_device *dev,
368			 struct nlattr *tb[], struct nlattr *data[])
 
369{
370	int err;
371	struct net_device *peer;
372	struct veth_priv *priv;
373	char ifname[IFNAMSIZ];
374	struct nlattr *peer_tb[IFLA_MAX + 1], **tbp;
375	unsigned char name_assign_type;
376	struct ifinfomsg *ifmp;
377	struct net *net;
378
379	/*
380	 * create and register peer first
381	 */
382	if (data != NULL && data[VETH_INFO_PEER] != NULL) {
383		struct nlattr *nla_peer;
384
385		nla_peer = data[VETH_INFO_PEER];
386		ifmp = nla_data(nla_peer);
387		err = rtnl_nla_parse_ifla(peer_tb,
388					  nla_data(nla_peer) + sizeof(struct ifinfomsg),
389					  nla_len(nla_peer) - sizeof(struct ifinfomsg));
 
390		if (err < 0)
391			return err;
392
393		err = veth_validate(peer_tb, NULL);
394		if (err < 0)
395			return err;
396
397		tbp = peer_tb;
398	} else {
399		ifmp = NULL;
400		tbp = tb;
401	}
402
403	if (tbp[IFLA_IFNAME]) {
404		nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
405		name_assign_type = NET_NAME_USER;
406	} else {
407		snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
408		name_assign_type = NET_NAME_ENUM;
409	}
410
411	net = rtnl_link_get_net(src_net, tbp);
412	if (IS_ERR(net))
413		return PTR_ERR(net);
414
415	peer = rtnl_create_link(net, ifname, name_assign_type,
416				&veth_link_ops, tbp);
417	if (IS_ERR(peer)) {
418		put_net(net);
419		return PTR_ERR(peer);
420	}
421
422	if (tbp[IFLA_ADDRESS] == NULL)
423		eth_hw_addr_random(peer);
424
425	if (ifmp && (dev->ifindex != 0))
426		peer->ifindex = ifmp->ifi_index;
 
 
 
427
428	err = register_netdevice(peer);
429	put_net(net);
430	net = NULL;
431	if (err < 0)
432		goto err_register_peer;
433
434	netif_carrier_off(peer);
435
436	err = rtnl_configure_link(peer, ifmp);
437	if (err < 0)
438		goto err_configure_peer;
439
440	/*
441	 * register dev last
442	 *
443	 * note, that since we've registered new device the dev's name
444	 * should be re-allocated
445	 */
446
447	if (tb[IFLA_ADDRESS] == NULL)
448		eth_hw_addr_random(dev);
449
450	if (tb[IFLA_IFNAME])
451		nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
452	else
453		snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
454
455	err = register_netdevice(dev);
456	if (err < 0)
457		goto err_register_dev;
458
459	netif_carrier_off(dev);
460
461	/*
462	 * tie the deviced together
463	 */
464
465	priv = netdev_priv(dev);
466	rcu_assign_pointer(priv->peer, peer);
467
468	priv = netdev_priv(peer);
469	rcu_assign_pointer(priv->peer, dev);
470	return 0;
471
472err_register_dev:
473	/* nothing to do */
474err_configure_peer:
475	unregister_netdevice(peer);
476	return err;
477
478err_register_peer:
479	free_netdev(peer);
480	return err;
481}
482
483static void veth_dellink(struct net_device *dev, struct list_head *head)
484{
485	struct veth_priv *priv;
486	struct net_device *peer;
487
488	priv = netdev_priv(dev);
489	peer = rtnl_dereference(priv->peer);
490
491	/* Note : dellink() is called from default_device_exit_batch(),
492	 * before a rcu_synchronize() point. The devices are guaranteed
493	 * not being freed before one RCU grace period.
494	 */
495	RCU_INIT_POINTER(priv->peer, NULL);
496	unregister_netdevice_queue(dev, head);
497
498	if (peer) {
499		priv = netdev_priv(peer);
500		RCU_INIT_POINTER(priv->peer, NULL);
501		unregister_netdevice_queue(peer, head);
502	}
503}
504
505static const struct nla_policy veth_policy[VETH_INFO_MAX + 1] = {
506	[VETH_INFO_PEER]	= { .len = sizeof(struct ifinfomsg) },
507};
508
509static struct net *veth_get_link_net(const struct net_device *dev)
510{
511	struct veth_priv *priv = netdev_priv(dev);
512	struct net_device *peer = rtnl_dereference(priv->peer);
513
514	return peer ? dev_net(peer) : dev_net(dev);
515}
516
517static struct rtnl_link_ops veth_link_ops = {
518	.kind		= DRV_NAME,
519	.priv_size	= sizeof(struct veth_priv),
520	.setup		= veth_setup,
521	.validate	= veth_validate,
522	.newlink	= veth_newlink,
523	.dellink	= veth_dellink,
524	.policy		= veth_policy,
525	.maxtype	= VETH_INFO_MAX,
526	.get_link_net	= veth_get_link_net,
527};
528
529/*
530 * init/fini
531 */
532
533static __init int veth_init(void)
534{
535	return rtnl_link_register(&veth_link_ops);
536}
537
538static __exit void veth_exit(void)
539{
540	rtnl_link_unregister(&veth_link_ops);
541}
542
543module_init(veth_init);
544module_exit(veth_exit);
545
546MODULE_DESCRIPTION("Virtual Ethernet Tunnel");
547MODULE_LICENSE("GPL v2");
548MODULE_ALIAS_RTNL_LINK(DRV_NAME);