aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/net/macvlan.c
blob: d5334b41e4b4eee895d1fd7d37d931956d56be1a (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
/*
 * Copyright (c) 2007 Patrick McHardy <kaber@trash.net>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * The code this is based on carried the following copyright notice:
 * ---
 * (C) Copyright 2001-2006
 * Alex Zeffertt, Cambridge Broadband Ltd, ajz@cambridgebroadband.com
 * Re-worked by Ben Greear <greearb@candelatech.com>
 * ---
 */
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/rculist.h>
#include <linux/notifier.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/if_arp.h>
#include <linux/if_link.h>
#include <linux/if_macvlan.h>
#include <net/rtnetlink.h>

#define MACVLAN_HASH_SIZE	(1 << BITS_PER_BYTE)

struct macvlan_port {
	struct net_device	*dev;
	struct hlist_head	vlan_hash[MACVLAN_HASH_SIZE];
	struct list_head	vlans;
};

struct macvlan_dev {
	struct net_device	*dev;
	struct list_head	list;
	struct hlist_node	hlist;
	struct macvlan_port	*port;
	struct net_device	*lowerdev;
};


static struct macvlan_dev *macvlan_hash_lookup(const struct macvlan_port *port,
					       const unsigned char *addr)
{
	struct macvlan_dev *vlan;
	struct hlist_node *n;

	hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[addr[5]], hlist) {
		if (!compare_ether_addr(vlan->dev->dev_addr, addr))
			return vlan;
	}
	return NULL;
}

static void macvlan_hash_add(struct macvlan_dev *vlan)
{
	struct macvlan_port *port = vlan->port;
	const unsigned char *addr = vlan->dev->dev_addr;

	hlist_add_head_rcu(&vlan->hlist, &port->vlan_hash[addr[5]]);
}

static void macvlan_hash_del(struct macvlan_dev *vlan)
{
	hlist_del_rcu(&vlan->hlist);
	synchronize_rcu();
}

static void macvlan_hash_change_addr(struct macvlan_dev *vlan,
					const unsigned char *addr)
{
	macvlan_hash_del(vlan);
	/* Now that we are unhashed it is safe to change the device
	 * address without confusing packet delivery.
	 */
	memcpy(vlan->dev->dev_addr, addr, ETH_ALEN);
	macvlan_hash_add(vlan);
}

static int macvlan_addr_busy(const struct macvlan_port *port,
				const unsigned char *addr)
{
	/* Test to see if the specified multicast address is
	 * currently in use by the underlying device or
	 * another macvlan.
	 */
	if (memcmp(port->dev->dev_addr, addr, ETH_ALEN) == 0)
		return 1;

	if (macvlan_hash_lookup(port, addr))
		return 1;

	return 0;
}

static void macvlan_broadcast(struct sk_buff *skb,
			      const struct macvlan_port *port)
{
	const struct ethhdr *eth = eth_hdr(skb);
	const struct macvlan_dev *vlan;
	struct hlist_node *n;
	struct net_device *dev;
	struct sk_buff *nskb;
	unsigned int i;

	if (skb->protocol == htons(ETH_P_PAUSE))
		return;

	for (i = 0; i < MACVLAN_HASH_SIZE; i++) {
		hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[i], hlist) {
			dev = vlan->dev;

			nskb = skb_clone(skb, GFP_ATOMIC);
			if (nskb == NULL) {
				dev->stats.rx_errors++;
				dev->stats.rx_dropped++;
				continue;
			}

			dev->stats.rx_bytes += skb->len + ETH_HLEN;
			dev->stats.rx_packets++;
			dev->stats.multicast++;

			nskb->dev = dev;
			if (!compare_ether_addr(eth->h_dest, dev->broadcast))
				nskb->pkt_type = PACKET_BROADCAST;
			else
				nskb->pkt_type = PACKET_MULTICAST;

			netif_rx(nskb);
		}
	}
}

/* called under rcu_read_lock() from netif_receive_skb */
static struct sk_buff *macvlan_handle_frame(struct sk_buff *skb)
{
	const struct ethhdr *eth = eth_hdr(skb);
	const struct macvlan_port *port;
	const struct macvlan_dev *vlan;
	struct net_device *dev;

	port = rcu_dereference(skb->dev->macvlan_port);
	if (port == NULL)
		return skb;

	if (is_multicast_ether_addr(eth->h_dest)) {
		macvlan_broadcast(skb, port);
		return skb;
	}

	vlan = macvlan_hash_lookup(port, eth->h_dest);
	if (vlan == NULL)
		return skb;

	dev = vlan->dev;
	if (unlikely(!(dev->flags & IFF_UP))) {
		kfree_skb(skb);
		return NULL;
	}

	skb = skb_share_check(skb, GFP_ATOMIC);
	if (skb == NULL) {
		dev->stats.rx_errors++;
		dev->stats.rx_dropped++;
		return NULL;
	}

	dev->stats.rx_bytes += skb->len + ETH_HLEN;
	dev->stats.rx_packets++;

	skb->dev = dev;
	skb->pkt_type = PACKET_HOST;

	netif_rx(skb);
	return NULL;
}

static int macvlan_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	const struct macvlan_dev *vlan = netdev_priv(dev);
	unsigned int len = skb->len;
	int ret;

	skb->dev = vlan->lowerdev;
	ret = dev_queue_xmit(skb);

	if (likely(ret == NET_XMIT_SUCCESS)) {
		dev->stats.tx_packets++;
		dev->stats.tx_bytes += len;
	} else {
		dev->stats.tx_errors++;
		dev->stats.tx_aborted_errors++;
	}
	return NETDEV_TX_OK;
}

static int macvlan_hard_header(struct sk_buff *skb, struct net_device *dev,
			       unsigned short type, const void *daddr,
			       const void *saddr, unsigned len)
{
	const struct macvlan_dev *vlan = netdev_priv(dev);
	struct net_device *lowerdev = vlan->lowerdev;

	return dev_hard_header(skb, lowerdev, type, daddr,
			       saddr ? : dev->dev_addr, len);
}

static const struct header_ops macvlan_hard_header_ops = {
	.create  	= macvlan_hard_header,
	.rebuild	= eth_rebuild_header,
	.parse		= eth_header_parse,
	.cache		= eth_header_cache,
	.cache_update	= eth_header_cache_update,
};

static int macvlan_open(struct net_device *dev)
{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct net_device *lowerdev = vlan->lowerdev;
	int err;

	err = -EBUSY;
	if (macvlan_addr_busy(vlan->port, dev->dev_addr))
		goto out;

	err = dev_unicast_add(lowerdev, dev->dev_addr, ETH_ALEN);
	if (err < 0)
		goto out;
	if (dev->flags & IFF_ALLMULTI) {
		err = dev_set_allmulti(lowerdev, 1);
		if (err < 0)
			goto del_unicast;
	}
	macvlan_hash_add(vlan);
	return 0;

del_unicast:
	dev_unicast_delete(lowerdev, dev->dev_addr, ETH_ALEN);
out:
	return err;
}

static int macvlan_stop(struct net_device *dev)
{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct net_device *lowerdev = vlan->lowerdev;

	dev_mc_unsync(lowerdev, dev);
	if (dev->flags & IFF_ALLMULTI)
		dev_set_allmulti(lowerdev, -1);

	dev_unicast_delete(lowerdev, dev->dev_addr, ETH_ALEN);

	macvlan_hash_del(vlan);
	return 0;
}

static int macvlan_set_mac_address(struct net_device *dev, void *p)
{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct net_device *lowerdev = vlan->lowerdev;
	struct sockaddr *addr = p;
	int err;

	if (!is_valid_ether_addr(addr->sa_data))
		return -EADDRNOTAVAIL;

	if (!(dev->flags & IFF_UP)) {
		/* Just copy in the new address */
		memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
	} else {
		/* Rehash and update the device filters */
		if (macvlan_addr_busy(vlan->port, addr->sa_data))
			return -EBUSY;

		if ((err = dev_unicast_add(lowerdev, addr->sa_data, ETH_ALEN)))
			return err;

		dev_unicast_delete(lowerdev, dev->dev_addr, ETH_ALEN);

		macvlan_hash_change_addr(vlan, addr->sa_data);
	}
	return 0;
}

static void macvlan_change_rx_flags(struct net_device *dev, int change)
{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct net_device *lowerdev = vlan->lowerdev;

	if (change & IFF_ALLMULTI)
		dev_set_allmulti(lowerdev, dev->flags & IFF_ALLMULTI ? 1 : -1);
}

static void macvlan_set_multicast_list(struct net_device *dev)
{
	struct macvlan_dev *vlan = netdev_priv(dev);

	dev_mc_sync(vlan->lowerdev, dev);
}

static int macvlan_change_mtu(struct net_device *dev, int new_mtu)
{
	struct macvlan_dev *vlan = netdev_priv(dev);

	if (new_mtu < 68 || vlan->lowerdev->mtu < new_mtu)
		return -EINVAL;
	dev->mtu = new_mtu;
	return 0;
}

/*
 * macvlan network devices have devices nesting below it and are a special
 * "super class" of normal network devices; split their locks off into a
 * separate class since they always nest.
 */
static struct lock_class_key macvlan_netdev_xmit_lock_key;
static struct lock_class_key macvlan_netdev_addr_lock_key;

#define MACVLAN_FEATURES \
	(NETIF_F_SG | NETIF_F_ALL_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
	 NETIF_F_GSO | NETIF_F_TSO | NETIF_F_UFO | NETIF_F_GSO_ROBUST | \
	 NETIF_F_TSO_ECN | NETIF_F_TSO6)

#define MACVLAN_STATE_MASK \
	((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))

static void macvlan_set_lockdep_class_one(struct net_device *dev,
					  struct netdev_queue *txq,
					  void *_unused)
{
	lockdep_set_class(&txq->_xmit_lock,
			  &macvlan_netdev_xmit_lock_key);
}

static void macvlan_set_lockdep_class(struct net_device *dev)
{
	lockdep_set_class(&dev->addr_list_lock,
			  &macvlan_netdev_addr_lock_key);
	netdev_for_each_tx_queue(dev, macvlan_set_lockdep_class_one, NULL);
}

static int macvlan_init(struct net_device *dev)
{
	struct macvlan_dev *vlan = netdev_priv(dev);
	const struct net_device *lowerdev = vlan->lowerdev;

	dev->state		= (dev->state & ~MACVLAN_STATE_MASK) |
				  (lowerdev->state & MACVLAN_STATE_MASK);
	dev->features 		= lowerdev->features & MACVLAN_FEATURES;
	dev->iflink		= lowerdev->ifindex;

	macvlan_set_lockdep_class(dev);

	return 0;
}

static void macvlan_ethtool_get_drvinfo(struct net_device *dev,
					struct ethtool_drvinfo *drvinfo)
{
	snprintf(drvinfo->driver, 32, "macvlan");
	snprintf(drvinfo->version, 32, "0.1");
}

static u32 macvlan_ethtool_get_rx_csum(struct net_device *dev)
{
	const struct macvlan_dev *vlan = netdev_priv(dev);
	return dev_ethtool_get_rx_csum(vlan->lowerdev);
}

static int macvlan_ethtool_get_settings(struct net_device *dev,
					struct ethtool_cmd *cmd)
{
	const struct macvlan_dev *vlan = netdev_priv(dev);
	return dev_ethtool_get_settings(vlan->lowerdev, cmd);
}

static u32 macvlan_ethtool_get_flags(struct net_device *dev)
{
	const struct macvlan_dev *vlan = netdev_priv(dev);
	return dev_ethtool_get_flags(vlan->lowerdev);
}

static const struct ethtool_ops macvlan_ethtool_ops = {
	.get_link		= ethtool_op_get_link,
	.get_settings		= macvlan_ethtool_get_settings,
	.get_rx_csum		= macvlan_ethtool_get_rx_csum,
	.get_drvinfo		= macvlan_ethtool_get_drvinfo,
	.get_flags		= macvlan_ethtool_get_flags,
};

static const struct net_device_ops macvlan_netdev_ops = {
	.ndo_init		= macvlan_init,
	.ndo_open		= macvlan_open,
	.ndo_stop		= macvlan_stop,
	.ndo_start_xmit		= macvlan_start_xmit,
	.ndo_change_mtu		= macvlan_change_mtu,
	.ndo_change_rx_flags	= macvlan_change_rx_flags,
	.ndo_set_mac_address	= macvlan_set_mac_address,
	.ndo_set_multicast_list	= macvlan_set_multicast_list,
	.ndo_validate_addr	= eth_validate_addr,
};

static void macvlan_setup(struct net_device *dev)
{
	ether_setup(dev);

	dev->priv_flags	       &= ~IFF_XMIT_DST_RELEASE;
	dev->netdev_ops		= &macvlan_netdev_ops;
	dev->destructor		= free_netdev;
	dev->header_ops		= &macvlan_hard_header_ops,
	dev->ethtool_ops	= &macvlan_ethtool_ops;
	dev->tx_queue_len	= 0;
}

static int macvlan_port_create(struct net_device *dev)
{
	struct macvlan_port *port;
	unsigned int i;

	if (dev->type != ARPHRD_ETHER || dev->flags & IFF_LOOPBACK)
		return -EINVAL;

	port = kzalloc(sizeof(*port), GFP_KERNEL);
	if (port == NULL)
		return -ENOMEM;

	port->dev = dev;
	INIT_LIST_HEAD(&port->vlans);
	for (i = 0; i < MACVLAN_HASH_SIZE; i++)
		INIT_HLIST_HEAD(&port->vlan_hash[i]);
	rcu_assign_pointer(dev->macvlan_port, port);
	return 0;
}

static void macvlan_port_destroy(struct net_device *dev)
{
	struct macvlan_port *port = dev->macvlan_port;

	rcu_assign_pointer(dev->macvlan_port, NULL);
	synchronize_rcu();
	kfree(port);
}

static void macvlan_transfer_operstate(struct net_device *dev)
{
	struct macvlan_dev *vlan = netdev_priv(dev);
	const struct net_device *lowerdev = vlan->lowerdev;

	if (lowerdev->operstate == IF_OPER_DORMANT)
		netif_dormant_on(dev);
	else
		netif_dormant_off(dev);

	if (netif_carrier_ok(lowerdev)) {
		if (!netif_carrier_ok(dev))
			netif_carrier_on(dev);
	} else {
		if (netif_carrier_ok(dev))
			netif_carrier_off(dev);
	}
}

static int macvlan_validate(struct nlattr *tb[], struct nlattr *data[])
{
	if (tb[IFLA_ADDRESS]) {
		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
			return -EINVAL;
		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
			return -EADDRNOTAVAIL;
	}
	return 0;
}

static int macvlan_newlink(struct net_device *dev,
			   struct nlattr *tb[], struct nlattr *data[])
{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct macvlan_port *port;
	struct net_device *lowerdev;
	int err;

	if (!tb[IFLA_LINK])
		return -EINVAL;

	lowerdev = __dev_get_by_index(dev_net(dev), nla_get_u32(tb[IFLA_LINK]));
	if (lowerdev == NULL)
		return -ENODEV;

	/* When creating macvlans on top of other macvlans - use
	 * the real device as the lowerdev.
	 */
	if (lowerdev->rtnl_link_ops == dev->rtnl_link_ops) {
		struct macvlan_dev *lowervlan = netdev_priv(lowerdev);
		lowerdev = lowervlan->lowerdev;
	}

	if (!tb[IFLA_MTU])
		dev->mtu = lowerdev->mtu;
	else if (dev->mtu > lowerdev->mtu)
		return -EINVAL;

	if (!tb[IFLA_ADDRESS])
		random_ether_addr(dev->dev_addr);

	if (lowerdev->macvlan_port == NULL) {
		err = macvlan_port_create(lowerdev);
		if (err < 0)
			return err;
	}
	port = lowerdev->macvlan_port;

	vlan->lowerdev = lowerdev;
	vlan->dev      = dev;
	vlan->port     = port;

	err = register_netdevice(dev);
	if (err < 0)
		return err;

	list_add_tail(&vlan->list, &port->vlans);
	macvlan_transfer_operstate(dev);
	return 0;
}

static void macvlan_dellink(struct net_device *dev)
{
	struct macvlan_dev *vlan = netdev_priv(dev);
	struct macvlan_port *port = vlan->port;

	list_del(&vlan->list);
	unregister_netdevice(dev);

	if (list_empty(&port->vlans))
		macvlan_port_destroy(port->dev);
}

static struct rtnl_link_ops macvlan_link_ops __read_mostly = {
	.kind		= "macvlan",
	.priv_size	= sizeof(struct macvlan_dev),
	.setup		= macvlan_setup,
	.validate	= macvlan_validate,
	.newlink	= macvlan_newlink,
	.dellink	= macvlan_dellink,
};

static int macvlan_device_event(struct notifier_block *unused,
				unsigned long event, void *ptr)
{
	struct net_device *dev = ptr;
	struct macvlan_dev *vlan, *next;
	struct macvlan_port *port;

	port = dev->macvlan_port;
	if (port == NULL)
		return NOTIFY_DONE;

	switch (event) {
	case NETDEV_CHANGE:
		list_for_each_entry(vlan, &port->vlans, list)
			macvlan_transfer_operstate(vlan->dev);
		break;
	case NETDEV_FEAT_CHANGE:
		list_for_each_entry(vlan, &port->vlans, list) {
			vlan->dev->features = dev->features & MACVLAN_FEATURES;
			netdev_features_change(vlan->dev);
		}
		break;
	case NETDEV_UNREGISTER:
		list_for_each_entry_safe(vlan, next, &port->vlans, list)
			macvlan_dellink(vlan->dev);
		break;
	}
	return NOTIFY_DONE;
}

static struct notifier_block macvlan_notifier_block __read_mostly = {
	.notifier_call	= macvlan_device_event,
};

static int __init macvlan_init_module(void)
{
	int err;

	register_netdevice_notifier(&macvlan_notifier_block);
	macvlan_handle_frame_hook = macvlan_handle_frame;

	err = rtnl_link_register(&macvlan_link_ops);
	if (err < 0)
		goto err1;
	return 0;
err1:
	macvlan_handle_frame_hook = NULL;
	unregister_netdevice_notifier(&macvlan_notifier_block);
	return err;
}

static void __exit macvlan_cleanup_module(void)
{
	rtnl_link_unregister(&macvlan_link_ops);
	macvlan_handle_frame_hook = NULL;
	unregister_netdevice_notifier(&macvlan_notifier_block);
}

module_init(macvlan_init_module);
module_exit(macvlan_cleanup_module);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_DESCRIPTION("Driver for MAC address based VLANs");
MODULE_ALIAS_RTNL_LINK("macvlan");