summaryrefslogtreecommitdiff
path: root/net/8021q/vlan.c
blob: b33410abfd6bfc25edd90a96bf05cde8014e96a3 (plain)
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
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
/*
 * INET		802.1Q VLAN
 *		Ethernet-type device handling.
 *
 * Authors:	Ben Greear <greearb@candelatech.com>
 *              Please send support related email to: netdev@vger.kernel.org
 *              VLAN Home Page: http://www.candelatech.com/~greear/vlan.html
 *
 * Fixes:
 *              Fix for packet capture - Nick Eggleston <nick@dccinc.com>;
 *		Add HW acceleration hooks - David S. Miller <davem@redhat.com>;
 *		Correct all the locking - David S. Miller <davem@redhat.com>;
 *		Use hash table for VLAN groups - David S. Miller <davem@redhat.com>
 *
 *		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.
 */

#include <asm/uaccess.h> /* for copy_from_user */
#include <linux/capability.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <net/datalink.h>
#include <linux/mm.h>
#include <linux/in.h>
#include <linux/init.h>
#include <net/p8022.h>
#include <net/arp.h>
#include <linux/rtnetlink.h>
#include <linux/notifier.h>
#include <net/net_namespace.h>

#include <linux/if_vlan.h>
#include "vlan.h"
#include "vlanproc.h"

#define DRV_VERSION "1.8"

/* Global VLAN variables */

/* Our listing of VLAN group(s) */
static struct hlist_head vlan_group_hash[VLAN_GRP_HASH_SIZE];

static char vlan_fullname[] = "802.1Q VLAN Support";
static char vlan_version[] = DRV_VERSION;
static char vlan_copyright[] = "Ben Greear <greearb@candelatech.com>";
static char vlan_buggyright[] = "David S. Miller <davem@redhat.com>";

/* Determines interface naming scheme. */
unsigned short vlan_name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD;

static struct packet_type vlan_packet_type = {
	.type = __constant_htons(ETH_P_8021Q),
	.func = vlan_skb_recv, /* VLAN receive method */
};

/* End of global variables definitions. */

static inline unsigned int vlan_grp_hashfn(unsigned int idx)
{
	return ((idx >> VLAN_GRP_HASH_SHIFT) ^ idx) & VLAN_GRP_HASH_MASK;
}

/* Must be invoked with RCU read lock (no preempt) */
static struct vlan_group *__vlan_find_group(int real_dev_ifindex)
{
	struct vlan_group *grp;
	struct hlist_node *n;
	int hash = vlan_grp_hashfn(real_dev_ifindex);

	hlist_for_each_entry_rcu(grp, n, &vlan_group_hash[hash], hlist) {
		if (grp->real_dev_ifindex == real_dev_ifindex)
			return grp;
	}

	return NULL;
}

/*  Find the protocol handler.  Assumes VID < VLAN_VID_MASK.
 *
 * Must be invoked with RCU read lock (no preempt)
 */
struct net_device *__find_vlan_dev(struct net_device *real_dev,
				   unsigned short VID)
{
	struct vlan_group *grp = __vlan_find_group(real_dev->ifindex);

	if (grp)
		return vlan_group_get_device(grp, VID);

	return NULL;
}

static void vlan_group_free(struct vlan_group *grp)
{
	int i;

	for (i = 0; i < VLAN_GROUP_ARRAY_SPLIT_PARTS; i++)
		kfree(grp->vlan_devices_arrays[i]);
	kfree(grp);
}

static struct vlan_group *vlan_group_alloc(int ifindex)
{
	struct vlan_group *grp;
	unsigned int size;
	unsigned int i;

	grp = kzalloc(sizeof(struct vlan_group), GFP_KERNEL);
	if (!grp)
		return NULL;

	size = sizeof(struct net_device *) * VLAN_GROUP_ARRAY_PART_LEN;

	for (i = 0; i < VLAN_GROUP_ARRAY_SPLIT_PARTS; i++) {
		grp->vlan_devices_arrays[i] = kzalloc(size, GFP_KERNEL);
		if (!grp->vlan_devices_arrays[i])
			goto err;
	}

	grp->real_dev_ifindex = ifindex;
	hlist_add_head_rcu(&grp->hlist,
			   &vlan_group_hash[vlan_grp_hashfn(ifindex)]);
	return grp;

err:
	vlan_group_free(grp);
	return NULL;
}

static void vlan_rcu_free(struct rcu_head *rcu)
{
	vlan_group_free(container_of(rcu, struct vlan_group, rcu));
}

void unregister_vlan_dev(struct net_device *dev)
{
	struct vlan_dev_info *vlan = vlan_dev_info(dev);
	struct net_device *real_dev = vlan->real_dev;
	struct vlan_group *grp;
	unsigned short vlan_id = vlan->vlan_id;

	ASSERT_RTNL();

	grp = __vlan_find_group(real_dev->ifindex);
	BUG_ON(!grp);

	vlan_proc_rem_dev(dev);

	/* Take it out of our own structures, but be sure to interlock with
	 * HW accelerating devices or SW vlan input packet processing.
	 */
	if (real_dev->features & NETIF_F_HW_VLAN_FILTER)
		real_dev->vlan_rx_kill_vid(real_dev, vlan_id);

	vlan_group_set_device(grp, vlan_id, NULL);
	grp->nr_vlans--;

	synchronize_net();

	/* If the group is now empty, kill off the group. */
	if (grp->nr_vlans == 0) {
		if (real_dev->features & NETIF_F_HW_VLAN_RX)
			real_dev->vlan_rx_register(real_dev, NULL);

		hlist_del_rcu(&grp->hlist);

		/* Free the group, after all cpu's are done. */
		call_rcu(&grp->rcu, vlan_rcu_free);
	}

	/* Get rid of the vlan's reference to real_dev */
	dev_put(real_dev);

	unregister_netdevice(dev);
}

static void vlan_transfer_operstate(const struct net_device *dev,
				    struct net_device *vlandev)
{
	/* Have to respect userspace enforced dormant state
	 * of real device, also must allow supplicant running
	 * on VLAN device
	 */
	if (dev->operstate == IF_OPER_DORMANT)
		netif_dormant_on(vlandev);
	else
		netif_dormant_off(vlandev);

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

int vlan_check_real_dev(struct net_device *real_dev, unsigned short vlan_id)
{
	char *name = real_dev->name;

	if (real_dev->features & NETIF_F_VLAN_CHALLENGED) {
		pr_info("8021q: VLANs not supported on %s\n", name);
		return -EOPNOTSUPP;
	}

	if ((real_dev->features & NETIF_F_HW_VLAN_RX) &&
	    !real_dev->vlan_rx_register) {
		pr_info("8021q: device %s has buggy VLAN hw accel\n", name);
		return -EOPNOTSUPP;
	}

	if ((real_dev->features & NETIF_F_HW_VLAN_FILTER) &&
	    (!real_dev->vlan_rx_add_vid || !real_dev->vlan_rx_kill_vid)) {
		pr_info("8021q: Device %s has buggy VLAN hw accel\n", name);
		return -EOPNOTSUPP;
	}

	/* The real device must be up and operating in order to
	 * assosciate a VLAN device with it.
	 */
	if (!(real_dev->flags & IFF_UP))
		return -ENETDOWN;

	if (__find_vlan_dev(real_dev, vlan_id) != NULL)
		return -EEXIST;

	return 0;
}

int register_vlan_dev(struct net_device *dev)
{
	struct vlan_dev_info *vlan = vlan_dev_info(dev);
	struct net_device *real_dev = vlan->real_dev;
	unsigned short vlan_id = vlan->vlan_id;
	struct vlan_group *grp, *ngrp = NULL;
	int err;

	grp = __vlan_find_group(real_dev->ifindex);
	if (!grp) {
		ngrp = grp = vlan_group_alloc(real_dev->ifindex);
		if (!grp)
			return -ENOBUFS;
	}

	err = register_netdevice(dev);
	if (err < 0)
		goto out_free_group;

	/* Account for reference in struct vlan_dev_info */
	dev_hold(real_dev);

	vlan_transfer_operstate(real_dev, dev);
	linkwatch_fire_event(dev); /* _MUST_ call rfc2863_policy() */

	/* So, got the sucker initialized, now lets place
	 * it into our local structure.
	 */
	vlan_group_set_device(grp, vlan_id, dev);
	grp->nr_vlans++;

	if (ngrp && real_dev->features & NETIF_F_HW_VLAN_RX)
		real_dev->vlan_rx_register(real_dev, ngrp);
	if (real_dev->features & NETIF_F_HW_VLAN_FILTER)
		real_dev->vlan_rx_add_vid(real_dev, vlan_id);

	if (vlan_proc_add_dev(dev) < 0)
		pr_warning("8021q: failed to add proc entry for %s\n",
			   dev->name);
	return 0;

out_free_group:
	if (ngrp)
		vlan_group_free(ngrp);
	return err;
}

/*  Attach a VLAN device to a mac address (ie Ethernet Card).
 *  Returns 0 if the device was created or a negative error code otherwise.
 */
static int register_vlan_device(struct net_device *real_dev,
				unsigned short VLAN_ID)
{
	struct net_device *new_dev;
	char name[IFNAMSIZ];
	int err;

	if (VLAN_ID >= VLAN_VID_MASK)
		return -ERANGE;

	err = vlan_check_real_dev(real_dev, VLAN_ID);
	if (err < 0)
		return err;

	/* Gotta set up the fields for the device. */
	switch (vlan_name_type) {
	case VLAN_NAME_TYPE_RAW_PLUS_VID:
		/* name will look like:	 eth1.0005 */
		snprintf(name, IFNAMSIZ, "%s.%.4i", real_dev->name, VLAN_ID);
		break;
	case VLAN_NAME_TYPE_PLUS_VID_NO_PAD:
		/* Put our vlan.VID in the name.
		 * Name will look like:	 vlan5
		 */
		snprintf(name, IFNAMSIZ, "vlan%i", VLAN_ID);
		break;
	case VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD:
		/* Put our vlan.VID in the name.
		 * Name will look like:	 eth0.5
		 */
		snprintf(name, IFNAMSIZ, "%s.%i", real_dev->name, VLAN_ID);
		break;
	case VLAN_NAME_TYPE_PLUS_VID:
		/* Put our vlan.VID in the name.
		 * Name will look like:	 vlan0005
		 */
	default:
		snprintf(name, IFNAMSIZ, "vlan%.4i", VLAN_ID);
	}

	new_dev = alloc_netdev(sizeof(struct vlan_dev_info), name,
			       vlan_setup);

	if (new_dev == NULL)
		return -ENOBUFS;

	/* need 4 bytes for extra VLAN header info,
	 * hope the underlying device can handle it.
	 */
	new_dev->mtu = real_dev->mtu;

	vlan_dev_info(new_dev)->vlan_id = VLAN_ID; /* 1 through VLAN_VID_MASK */
	vlan_dev_info(new_dev)->real_dev = real_dev;
	vlan_dev_info(new_dev)->dent = NULL;
	vlan_dev_info(new_dev)->flags = VLAN_FLAG_REORDER_HDR;

	new_dev->rtnl_link_ops = &vlan_link_ops;
	err = register_vlan_dev(new_dev);
	if (err < 0)
		goto out_free_newdev;

	return 0;

out_free_newdev:
	free_netdev(new_dev);
	return err;
}

static void vlan_sync_address(struct net_device *dev,
			      struct net_device *vlandev)
{
	struct vlan_dev_info *vlan = vlan_dev_info(vlandev);

	/* May be called without an actual change */
	if (!compare_ether_addr(vlan->real_dev_addr, dev->dev_addr))
		return;

	/* vlan address was different from the old address and is equal to
	 * the new address */
	if (compare_ether_addr(vlandev->dev_addr, vlan->real_dev_addr) &&
	    !compare_ether_addr(vlandev->dev_addr, dev->dev_addr))
		dev_unicast_delete(dev, vlandev->dev_addr, ETH_ALEN);

	/* vlan address was equal to the old address and is different from
	 * the new address */
	if (!compare_ether_addr(vlandev->dev_addr, vlan->real_dev_addr) &&
	    compare_ether_addr(vlandev->dev_addr, dev->dev_addr))
		dev_unicast_add(dev, vlandev->dev_addr, ETH_ALEN);

	memcpy(vlan->real_dev_addr, dev->dev_addr, ETH_ALEN);
}

static void __vlan_device_event(struct net_device *dev, unsigned long event)
{
	switch (event) {
	case NETDEV_CHANGENAME:
		vlan_proc_rem_dev(dev);
		if (vlan_proc_add_dev(dev) < 0)
			pr_warning("8021q: failed to change proc name for %s\n",
					dev->name);
		break;
	}
}

static int vlan_device_event(struct notifier_block *unused, unsigned long event,
			     void *ptr)
{
	struct net_device *dev = ptr;
	struct vlan_group *grp;
	int i, flgs;
	struct net_device *vlandev;

	if (dev->nd_net != &init_net)
		return NOTIFY_DONE;

	if (is_vlan_dev(dev)) {
		__vlan_device_event(dev, event);
		goto out;
	}

	grp = __vlan_find_group(dev->ifindex);
	if (!grp)
		goto out;

	/* It is OK that we do not hold the group lock right now,
	 * as we run under the RTNL lock.
	 */

	switch (event) {
	case NETDEV_CHANGE:
		/* Propagate real device state to vlan devices */
		for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
			vlandev = vlan_group_get_device(grp, i);
			if (!vlandev)
				continue;

			vlan_transfer_operstate(dev, vlandev);
		}
		break;

	case NETDEV_CHANGEADDR:
		/* Adjust unicast filters on underlying device */
		for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
			vlandev = vlan_group_get_device(grp, i);
			if (!vlandev)
				continue;

			flgs = vlandev->flags;
			if (!(flgs & IFF_UP))
				continue;

			vlan_sync_address(dev, vlandev);
		}
		break;

	case NETDEV_DOWN:
		/* Put all VLANs for this dev in the down state too.  */
		for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
			vlandev = vlan_group_get_device(grp, i);
			if (!vlandev)
				continue;

			flgs = vlandev->flags;
			if (!(flgs & IFF_UP))
				continue;

			dev_change_flags(vlandev, flgs & ~IFF_UP);
		}
		break;

	case NETDEV_UP:
		/* Put all VLANs for this dev in the up state too.  */
		for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
			vlandev = vlan_group_get_device(grp, i);
			if (!vlandev)
				continue;

			flgs = vlandev->flags;
			if (flgs & IFF_UP)
				continue;

			dev_change_flags(vlandev, flgs | IFF_UP);
		}
		break;

	case NETDEV_UNREGISTER:
		/* Delete all VLANs for this dev. */
		for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
			vlandev = vlan_group_get_device(grp, i);
			if (!vlandev)
				continue;

			/* unregistration of last vlan destroys group, abort
			 * afterwards */
			if (grp->nr_vlans == 1)
				i = VLAN_GROUP_ARRAY_LEN;

			unregister_vlan_dev(vlandev);
		}
		break;
	}

out:
	return NOTIFY_DONE;
}

static struct notifier_block vlan_notifier_block __read_mostly = {
	.notifier_call = vlan_device_event,
};

/*
 *	VLAN IOCTL handler.
 *	o execute requested action or pass command to the device driver
 *   arg is really a struct vlan_ioctl_args __user *.
 */
static int vlan_ioctl_handler(struct net *net, void __user *arg)
{
	int err;
	unsigned short vid = 0;
	struct vlan_ioctl_args args;
	struct net_device *dev = NULL;

	if (copy_from_user(&args, arg, sizeof(struct vlan_ioctl_args)))
		return -EFAULT;

	/* Null terminate this sucker, just in case. */
	args.device1[23] = 0;
	args.u.device2[23] = 0;

	rtnl_lock();

	switch (args.cmd) {
	case SET_VLAN_INGRESS_PRIORITY_CMD:
	case SET_VLAN_EGRESS_PRIORITY_CMD:
	case SET_VLAN_FLAG_CMD:
	case ADD_VLAN_CMD:
	case DEL_VLAN_CMD:
	case GET_VLAN_REALDEV_NAME_CMD:
	case GET_VLAN_VID_CMD:
		err = -ENODEV;
		dev = __dev_get_by_name(&init_net, args.device1);
		if (!dev)
			goto out;

		err = -EINVAL;
		if (args.cmd != ADD_VLAN_CMD &&
		    !(dev->priv_flags & IFF_802_1Q_VLAN))
			goto out;
	}

	switch (args.cmd) {
	case SET_VLAN_INGRESS_PRIORITY_CMD:
		err = -EPERM;
		if (!capable(CAP_NET_ADMIN))
			break;
		vlan_dev_set_ingress_priority(dev,
					      args.u.skb_priority,
					      args.vlan_qos);
		err = 0;
		break;

	case SET_VLAN_EGRESS_PRIORITY_CMD:
		err = -EPERM;
		if (!capable(CAP_NET_ADMIN))
			break;
		err = vlan_dev_set_egress_priority(dev,
						   args.u.skb_priority,
						   args.vlan_qos);
		break;

	case SET_VLAN_FLAG_CMD:
		err = -EPERM;
		if (!capable(CAP_NET_ADMIN))
			break;
		err = vlan_dev_set_vlan_flag(dev,
					     args.u.flag,
					     args.vlan_qos);
		break;

	case SET_VLAN_NAME_TYPE_CMD:
		err = -EPERM;
		if (!capable(CAP_NET_ADMIN))
			break;
		if ((args.u.name_type >= 0) &&
		    (args.u.name_type < VLAN_NAME_TYPE_HIGHEST)) {
			vlan_name_type = args.u.name_type;
			err = 0;
		} else {
			err = -EINVAL;
		}
		break;

	case ADD_VLAN_CMD:
		err = -EPERM;
		if (!capable(CAP_NET_ADMIN))
			break;
		err = register_vlan_device(dev, args.u.VID);
		break;

	case DEL_VLAN_CMD:
		err = -EPERM;
		if (!capable(CAP_NET_ADMIN))
			break;
		unregister_vlan_dev(dev);
		err = 0;
		break;

	case GET_VLAN_REALDEV_NAME_CMD:
		err = 0;
		vlan_dev_get_realdev_name(dev, args.u.device2);
		if (copy_to_user(arg, &args,
				 sizeof(struct vlan_ioctl_args)))
			err = -EFAULT;
		break;

	case GET_VLAN_VID_CMD:
		err = 0;
		vlan_dev_get_vid(dev, &vid);
		args.u.VID = vid;
		if (copy_to_user(arg, &args,
				 sizeof(struct vlan_ioctl_args)))
		      err = -EFAULT;
		break;

	default:
		err = -EOPNOTSUPP;
		break;
	}
out:
	rtnl_unlock();
	return err;
}

static int __init vlan_proto_init(void)
{
	int err;

	pr_info("%s v%s %s\n", vlan_fullname, vlan_version, vlan_copyright);
	pr_info("All bugs added by %s\n", vlan_buggyright);

	err = vlan_proc_init();
	if (err < 0)
		goto err1;

	err = register_netdevice_notifier(&vlan_notifier_block);
	if (err < 0)
		goto err2;

	err = vlan_netlink_init();
	if (err < 0)
		goto err3;

	dev_add_pack(&vlan_packet_type);
	vlan_ioctl_set(vlan_ioctl_handler);
	return 0;

err3:
	unregister_netdevice_notifier(&vlan_notifier_block);
err2:
	vlan_proc_cleanup();
err1:
	return err;
}

static void __exit vlan_cleanup_module(void)
{
	unsigned int i;

	vlan_ioctl_set(NULL);
	vlan_netlink_fini();

	unregister_netdevice_notifier(&vlan_notifier_block);

	dev_remove_pack(&vlan_packet_type);

	/* This table must be empty if there are no module references left. */
	for (i = 0; i < VLAN_GRP_HASH_SIZE; i++)
		BUG_ON(!hlist_empty(&vlan_group_hash[i]));

	vlan_proc_cleanup();

	synchronize_net();
}

module_init(vlan_proto_init);
module_exit(vlan_cleanup_module);

MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);