vlan.c revision d932e04a5e7b146c5f9bf517714b986a432a7594
1/*
2 * INET		802.1Q VLAN
3 *		Ethernet-type device handling.
4 *
5 * Authors:	Ben Greear <greearb@candelatech.com>
6 *              Please send support related email to: vlan@scry.wanfear.com
7 *              VLAN Home Page: http://www.candelatech.com/~greear/vlan.html
8 *
9 * Fixes:
10 *              Fix for packet capture - Nick Eggleston <nick@dccinc.com>;
11 *		Add HW acceleration hooks - David S. Miller <davem@redhat.com>;
12 *		Correct all the locking - David S. Miller <davem@redhat.com>;
13 *		Use hash table for VLAN groups - David S. Miller <davem@redhat.com>
14 *
15 *		This program is free software; you can redistribute it and/or
16 *		modify it under the terms of the GNU General Public License
17 *		as published by the Free Software Foundation; either version
18 *		2 of the License, or (at your option) any later version.
19 */
20
21#include <asm/uaccess.h> /* for copy_from_user */
22#include <linux/capability.h>
23#include <linux/module.h>
24#include <linux/netdevice.h>
25#include <linux/skbuff.h>
26#include <net/datalink.h>
27#include <linux/mm.h>
28#include <linux/in.h>
29#include <linux/init.h>
30#include <net/p8022.h>
31#include <net/arp.h>
32#include <linux/rtnetlink.h>
33#include <linux/notifier.h>
34#include <net/net_namespace.h>
35
36#include <linux/if_vlan.h>
37#include "vlan.h"
38#include "vlanproc.h"
39
40#define DRV_VERSION "1.8"
41
42/* Global VLAN variables */
43
44/* Our listing of VLAN group(s) */
45static struct hlist_head vlan_group_hash[VLAN_GRP_HASH_SIZE];
46#define vlan_grp_hashfn(IDX)	((((IDX) >> VLAN_GRP_HASH_SHIFT) ^ (IDX)) & VLAN_GRP_HASH_MASK)
47
48static char vlan_fullname[] = "802.1Q VLAN Support";
49static char vlan_version[] = DRV_VERSION;
50static char vlan_copyright[] = "Ben Greear <greearb@candelatech.com>";
51static char vlan_buggyright[] = "David S. Miller <davem@redhat.com>";
52
53static int vlan_device_event(struct notifier_block *, unsigned long, void *);
54static int vlan_ioctl_handler(struct net *net, void __user *);
55static int unregister_vlan_dev(struct net_device *, unsigned short );
56
57static struct notifier_block vlan_notifier_block = {
58	.notifier_call = vlan_device_event,
59};
60
61/* These may be changed at run-time through IOCTLs */
62
63/* Determines interface naming scheme. */
64unsigned short vlan_name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD;
65
66static struct packet_type vlan_packet_type = {
67	.type = __constant_htons(ETH_P_8021Q),
68	.func = vlan_skb_recv, /* VLAN receive method */
69};
70
71/* End of global variables definitions. */
72
73/*
74 * Function vlan_proto_init (pro)
75 *
76 *    Initialize VLAN protocol layer,
77 *
78 */
79static int __init vlan_proto_init(void)
80{
81	int err;
82
83	printk(VLAN_INF "%s v%s %s\n",
84	       vlan_fullname, vlan_version, vlan_copyright);
85	printk(VLAN_INF "All bugs added by %s\n",
86	       vlan_buggyright);
87
88	/* proc file system initialization */
89	err = vlan_proc_init();
90	if (err < 0) {
91		printk(KERN_ERR
92		       "%s %s: can't create entry in proc filesystem!\n",
93		       __FUNCTION__, VLAN_NAME);
94		return err;
95	}
96
97	dev_add_pack(&vlan_packet_type);
98
99	/* Register us to receive netdevice events */
100	err = register_netdevice_notifier(&vlan_notifier_block);
101	if (err < 0)
102		goto err1;
103
104	err = vlan_netlink_init();
105	if (err < 0)
106		goto err2;
107
108	vlan_ioctl_set(vlan_ioctl_handler);
109	return 0;
110
111err2:
112	unregister_netdevice_notifier(&vlan_notifier_block);
113err1:
114	vlan_proc_cleanup();
115	dev_remove_pack(&vlan_packet_type);
116	return err;
117}
118
119/*
120 *     Module 'remove' entry point.
121 *     o delete /proc/net/router directory and static entries.
122 */
123static void __exit vlan_cleanup_module(void)
124{
125	int i;
126
127	vlan_netlink_fini();
128	vlan_ioctl_set(NULL);
129
130	/* Un-register us from receiving netdevice events */
131	unregister_netdevice_notifier(&vlan_notifier_block);
132
133	dev_remove_pack(&vlan_packet_type);
134
135	/* This table must be empty if there are no module
136	 * references left.
137	 */
138	for (i = 0; i < VLAN_GRP_HASH_SIZE; i++) {
139		BUG_ON(!hlist_empty(&vlan_group_hash[i]));
140	}
141	vlan_proc_cleanup();
142
143	synchronize_net();
144}
145
146module_init(vlan_proto_init);
147module_exit(vlan_cleanup_module);
148
149/* Must be invoked with RCU read lock (no preempt) */
150static struct vlan_group *__vlan_find_group(int real_dev_ifindex)
151{
152	struct vlan_group *grp;
153	struct hlist_node *n;
154	int hash = vlan_grp_hashfn(real_dev_ifindex);
155
156	hlist_for_each_entry_rcu(grp, n, &vlan_group_hash[hash], hlist) {
157		if (grp->real_dev_ifindex == real_dev_ifindex)
158			return grp;
159	}
160
161	return NULL;
162}
163
164/*  Find the protocol handler.  Assumes VID < VLAN_VID_MASK.
165 *
166 * Must be invoked with RCU read lock (no preempt)
167 */
168struct net_device *__find_vlan_dev(struct net_device *real_dev,
169				   unsigned short VID)
170{
171	struct vlan_group *grp = __vlan_find_group(real_dev->ifindex);
172
173	if (grp)
174		return vlan_group_get_device(grp, VID);
175
176	return NULL;
177}
178
179static void vlan_group_free(struct vlan_group *grp)
180{
181	int i;
182
183	for (i=0; i < VLAN_GROUP_ARRAY_SPLIT_PARTS; i++)
184		kfree(grp->vlan_devices_arrays[i]);
185	kfree(grp);
186}
187
188static struct vlan_group *vlan_group_alloc(int ifindex)
189{
190	struct vlan_group *grp;
191	unsigned int size;
192	unsigned int i;
193
194	grp = kzalloc(sizeof(struct vlan_group), GFP_KERNEL);
195	if (!grp)
196		return NULL;
197
198	size = sizeof(struct net_device *) * VLAN_GROUP_ARRAY_PART_LEN;
199
200	for (i = 0; i < VLAN_GROUP_ARRAY_SPLIT_PARTS; i++) {
201		grp->vlan_devices_arrays[i] = kzalloc(size, GFP_KERNEL);
202		if (!grp->vlan_devices_arrays[i])
203			goto err;
204	}
205
206	grp->real_dev_ifindex = ifindex;
207	hlist_add_head_rcu(&grp->hlist,
208			   &vlan_group_hash[vlan_grp_hashfn(ifindex)]);
209	return grp;
210
211err:
212	vlan_group_free(grp);
213	return NULL;
214}
215
216static void vlan_rcu_free(struct rcu_head *rcu)
217{
218	vlan_group_free(container_of(rcu, struct vlan_group, rcu));
219}
220
221
222/* This returns 0 if everything went fine.
223 * It will return 1 if the group was killed as a result.
224 * A negative return indicates failure.
225 *
226 * The RTNL lock must be held.
227 */
228static int unregister_vlan_dev(struct net_device *real_dev,
229			       unsigned short vlan_id)
230{
231	struct net_device *dev = NULL;
232	int real_dev_ifindex = real_dev->ifindex;
233	struct vlan_group *grp;
234	int i, ret;
235
236#ifdef VLAN_DEBUG
237	printk(VLAN_DBG "%s: VID: %i\n", __FUNCTION__, vlan_id);
238#endif
239
240	/* sanity check */
241	if (vlan_id >= VLAN_VID_MASK)
242		return -EINVAL;
243
244	ASSERT_RTNL();
245	grp = __vlan_find_group(real_dev_ifindex);
246
247	ret = 0;
248
249	if (grp) {
250		dev = vlan_group_get_device(grp, vlan_id);
251		if (dev) {
252			/* Remove proc entry */
253			vlan_proc_rem_dev(dev);
254
255			/* Take it out of our own structures, but be sure to
256			 * interlock with HW accelerating devices or SW vlan
257			 * input packet processing.
258			 */
259			if (real_dev->features & NETIF_F_HW_VLAN_FILTER)
260				real_dev->vlan_rx_kill_vid(real_dev, vlan_id);
261
262			vlan_group_set_device(grp, vlan_id, NULL);
263			synchronize_net();
264
265
266			/* Caller unregisters (and if necessary, puts)
267			 * VLAN device, but we get rid of the reference to
268			 * real_dev here.
269			 */
270			dev_put(real_dev);
271
272			/* If the group is now empty, kill off the
273			 * group.
274			 */
275			for (i = 0; i < VLAN_VID_MASK; i++)
276				if (vlan_group_get_device(grp, i))
277					break;
278
279			if (i == VLAN_VID_MASK) {
280				if (real_dev->features & NETIF_F_HW_VLAN_RX)
281					real_dev->vlan_rx_register(real_dev, NULL);
282
283				hlist_del_rcu(&grp->hlist);
284
285				/* Free the group, after all cpu's are done. */
286				call_rcu(&grp->rcu, vlan_rcu_free);
287
288				grp = NULL;
289				ret = 1;
290			}
291		}
292	}
293
294	return ret;
295}
296
297int unregister_vlan_device(struct net_device *dev)
298{
299	int ret;
300
301	ret = unregister_vlan_dev(VLAN_DEV_INFO(dev)->real_dev,
302				  VLAN_DEV_INFO(dev)->vlan_id);
303	unregister_netdevice(dev);
304
305	if (ret == 1)
306		ret = 0;
307	return ret;
308}
309
310/*
311 * vlan network devices have devices nesting below it, and are a special
312 * "super class" of normal network devices; split their locks off into a
313 * separate class since they always nest.
314 */
315static struct lock_class_key vlan_netdev_xmit_lock_key;
316
317static const struct header_ops vlan_header_ops = {
318	.create	 = vlan_dev_hard_header,
319	.rebuild = vlan_dev_rebuild_header,
320	.parse	 = eth_header_parse,
321};
322
323static int vlan_dev_init(struct net_device *dev)
324{
325	struct net_device *real_dev = VLAN_DEV_INFO(dev)->real_dev;
326
327	/* IFF_BROADCAST|IFF_MULTICAST; ??? */
328	dev->flags  = real_dev->flags & ~IFF_UP;
329	dev->iflink = real_dev->ifindex;
330	dev->state  = (real_dev->state & ((1<<__LINK_STATE_NOCARRIER) |
331					  (1<<__LINK_STATE_DORMANT))) |
332		      (1<<__LINK_STATE_PRESENT);
333
334	/* ipv6 shared card related stuff */
335	dev->dev_id = real_dev->dev_id;
336
337	if (is_zero_ether_addr(dev->dev_addr))
338		memcpy(dev->dev_addr, real_dev->dev_addr, dev->addr_len);
339	if (is_zero_ether_addr(dev->broadcast))
340		memcpy(dev->broadcast, real_dev->broadcast, dev->addr_len);
341
342	if (real_dev->features & NETIF_F_HW_VLAN_TX) {
343		dev->header_ops      = real_dev->header_ops;
344		dev->hard_header_len = real_dev->hard_header_len;
345		dev->hard_start_xmit = vlan_dev_hwaccel_hard_start_xmit;
346	} else {
347		dev->header_ops      = &vlan_header_ops;
348		dev->hard_header_len = real_dev->hard_header_len + VLAN_HLEN;
349		dev->hard_start_xmit = vlan_dev_hard_start_xmit;
350	}
351
352	lockdep_set_class(&dev->_xmit_lock, &vlan_netdev_xmit_lock_key);
353	return 0;
354}
355
356void vlan_setup(struct net_device *new_dev)
357{
358	ether_setup(new_dev);
359
360	/* new_dev->ifindex = 0;  it will be set when added to
361	 * the global list.
362	 * iflink is set as well.
363	 */
364	new_dev->get_stats = vlan_dev_get_stats;
365
366	/* Make this thing known as a VLAN device */
367	new_dev->priv_flags |= IFF_802_1Q_VLAN;
368
369	/* Set us up to have no queue, as the underlying Hardware device
370	 * can do all the queueing we could want.
371	 */
372	new_dev->tx_queue_len = 0;
373
374	/* set up method calls */
375	new_dev->change_mtu = vlan_dev_change_mtu;
376	new_dev->init = vlan_dev_init;
377	new_dev->open = vlan_dev_open;
378	new_dev->stop = vlan_dev_stop;
379	new_dev->set_multicast_list = vlan_dev_set_multicast_list;
380	new_dev->change_rx_flags = vlan_change_rx_flags;
381	new_dev->destructor = free_netdev;
382	new_dev->do_ioctl = vlan_dev_ioctl;
383
384	memset(new_dev->broadcast, 0, ETH_ALEN);
385}
386
387static void vlan_transfer_operstate(const struct net_device *dev, struct net_device *vlandev)
388{
389	/* Have to respect userspace enforced dormant state
390	 * of real device, also must allow supplicant running
391	 * on VLAN device
392	 */
393	if (dev->operstate == IF_OPER_DORMANT)
394		netif_dormant_on(vlandev);
395	else
396		netif_dormant_off(vlandev);
397
398	if (netif_carrier_ok(dev)) {
399		if (!netif_carrier_ok(vlandev))
400			netif_carrier_on(vlandev);
401	} else {
402		if (netif_carrier_ok(vlandev))
403			netif_carrier_off(vlandev);
404	}
405}
406
407int vlan_check_real_dev(struct net_device *real_dev, unsigned short vlan_id)
408{
409	if (real_dev->features & NETIF_F_VLAN_CHALLENGED) {
410		printk(VLAN_DBG "%s: VLANs not supported on %s.\n",
411			__FUNCTION__, real_dev->name);
412		return -EOPNOTSUPP;
413	}
414
415	if ((real_dev->features & NETIF_F_HW_VLAN_RX) &&
416	    !real_dev->vlan_rx_register) {
417		printk(VLAN_DBG "%s: Device %s has buggy VLAN hw accel.\n",
418			__FUNCTION__, real_dev->name);
419		return -EOPNOTSUPP;
420	}
421
422	if ((real_dev->features & NETIF_F_HW_VLAN_FILTER) &&
423	    (!real_dev->vlan_rx_add_vid || !real_dev->vlan_rx_kill_vid)) {
424		printk(VLAN_DBG "%s: Device %s has buggy VLAN hw accel.\n",
425			__FUNCTION__, real_dev->name);
426		return -EOPNOTSUPP;
427	}
428
429	/* The real device must be up and operating in order to
430	 * assosciate a VLAN device with it.
431	 */
432	if (!(real_dev->flags & IFF_UP))
433		return -ENETDOWN;
434
435	if (__find_vlan_dev(real_dev, vlan_id) != NULL) {
436		/* was already registered. */
437		printk(VLAN_DBG "%s: ALREADY had VLAN registered\n", __FUNCTION__);
438		return -EEXIST;
439	}
440
441	return 0;
442}
443
444int register_vlan_dev(struct net_device *dev)
445{
446	struct vlan_dev_info *vlan = VLAN_DEV_INFO(dev);
447	struct net_device *real_dev = vlan->real_dev;
448	unsigned short vlan_id = vlan->vlan_id;
449	struct vlan_group *grp, *ngrp = NULL;
450	int err;
451
452	grp = __vlan_find_group(real_dev->ifindex);
453	if (!grp) {
454		ngrp = grp = vlan_group_alloc(real_dev->ifindex);
455		if (!grp)
456			return -ENOBUFS;
457	}
458
459	err = register_netdevice(dev);
460	if (err < 0)
461		goto out_free_group;
462
463	/* Account for reference in struct vlan_dev_info */
464	dev_hold(real_dev);
465
466	vlan_transfer_operstate(real_dev, dev);
467	linkwatch_fire_event(dev); /* _MUST_ call rfc2863_policy() */
468
469	/* So, got the sucker initialized, now lets place
470	 * it into our local structure.
471	 */
472	vlan_group_set_device(grp, vlan_id, dev);
473	if (ngrp && real_dev->features & NETIF_F_HW_VLAN_RX)
474		real_dev->vlan_rx_register(real_dev, ngrp);
475	if (real_dev->features & NETIF_F_HW_VLAN_FILTER)
476		real_dev->vlan_rx_add_vid(real_dev, vlan_id);
477
478	if (vlan_proc_add_dev(dev) < 0)
479		printk(KERN_WARNING "VLAN: failed to add proc entry for %s\n",
480		       dev->name);
481	return 0;
482
483out_free_group:
484	if (ngrp)
485		vlan_group_free(ngrp);
486	return err;
487}
488
489/*  Attach a VLAN device to a mac address (ie Ethernet Card).
490 *  Returns 0 if the device was created or a negative error code otherwise.
491 */
492static int register_vlan_device(struct net_device *real_dev,
493				unsigned short VLAN_ID)
494{
495	struct net_device *new_dev;
496	char name[IFNAMSIZ];
497	int err;
498
499#ifdef VLAN_DEBUG
500	printk(VLAN_DBG "%s: if_name -:%s:-	vid: %i\n",
501		__FUNCTION__, eth_IF_name, VLAN_ID);
502#endif
503
504	if (VLAN_ID >= VLAN_VID_MASK)
505		return -ERANGE;
506
507	err = vlan_check_real_dev(real_dev, VLAN_ID);
508	if (err < 0)
509		return err;
510
511	/* Gotta set up the fields for the device. */
512#ifdef VLAN_DEBUG
513	printk(VLAN_DBG "About to allocate name, vlan_name_type: %i\n",
514	       vlan_name_type);
515#endif
516	switch (vlan_name_type) {
517	case VLAN_NAME_TYPE_RAW_PLUS_VID:
518		/* name will look like:	 eth1.0005 */
519		snprintf(name, IFNAMSIZ, "%s.%.4i", real_dev->name, VLAN_ID);
520		break;
521	case VLAN_NAME_TYPE_PLUS_VID_NO_PAD:
522		/* Put our vlan.VID in the name.
523		 * Name will look like:	 vlan5
524		 */
525		snprintf(name, IFNAMSIZ, "vlan%i", VLAN_ID);
526		break;
527	case VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD:
528		/* Put our vlan.VID in the name.
529		 * Name will look like:	 eth0.5
530		 */
531		snprintf(name, IFNAMSIZ, "%s.%i", real_dev->name, VLAN_ID);
532		break;
533	case VLAN_NAME_TYPE_PLUS_VID:
534		/* Put our vlan.VID in the name.
535		 * Name will look like:	 vlan0005
536		 */
537	default:
538		snprintf(name, IFNAMSIZ, "vlan%.4i", VLAN_ID);
539	}
540
541	new_dev = alloc_netdev(sizeof(struct vlan_dev_info), name,
542			       vlan_setup);
543
544	if (new_dev == NULL)
545		return -ENOBUFS;
546
547	/* need 4 bytes for extra VLAN header info,
548	 * hope the underlying device can handle it.
549	 */
550	new_dev->mtu = real_dev->mtu;
551
552#ifdef VLAN_DEBUG
553	printk(VLAN_DBG "Allocated new name -:%s:-\n", new_dev->name);
554	VLAN_MEM_DBG("new_dev->priv malloc, addr: %p  size: %i\n",
555		     new_dev->priv,
556		     sizeof(struct vlan_dev_info));
557#endif
558
559	VLAN_DEV_INFO(new_dev)->vlan_id = VLAN_ID; /* 1 through VLAN_VID_MASK */
560	VLAN_DEV_INFO(new_dev)->real_dev = real_dev;
561	VLAN_DEV_INFO(new_dev)->dent = NULL;
562	VLAN_DEV_INFO(new_dev)->flags = VLAN_FLAG_REORDER_HDR;
563
564	new_dev->rtnl_link_ops = &vlan_link_ops;
565	err = register_vlan_dev(new_dev);
566	if (err < 0)
567		goto out_free_newdev;
568
569#ifdef VLAN_DEBUG
570	printk(VLAN_DBG "Allocated new device successfully, returning.\n");
571#endif
572	return 0;
573
574out_free_newdev:
575	free_netdev(new_dev);
576	return err;
577}
578
579static void vlan_sync_address(struct net_device *dev,
580			      struct net_device *vlandev)
581{
582	struct vlan_dev_info *vlan = VLAN_DEV_INFO(vlandev);
583
584	/* May be called without an actual change */
585	if (!compare_ether_addr(vlan->real_dev_addr, dev->dev_addr))
586		return;
587
588	/* vlan address was different from the old address and is equal to
589	 * the new address */
590	if (compare_ether_addr(vlandev->dev_addr, vlan->real_dev_addr) &&
591	    !compare_ether_addr(vlandev->dev_addr, dev->dev_addr))
592		dev_unicast_delete(dev, vlandev->dev_addr, ETH_ALEN);
593
594	/* vlan address was equal to the old address and is different from
595	 * the new address */
596	if (!compare_ether_addr(vlandev->dev_addr, vlan->real_dev_addr) &&
597	    compare_ether_addr(vlandev->dev_addr, dev->dev_addr))
598		dev_unicast_add(dev, vlandev->dev_addr, ETH_ALEN);
599
600	memcpy(vlan->real_dev_addr, dev->dev_addr, ETH_ALEN);
601}
602
603static int vlan_device_event(struct notifier_block *unused, unsigned long event, void *ptr)
604{
605	struct net_device *dev = ptr;
606	struct vlan_group *grp = __vlan_find_group(dev->ifindex);
607	int i, flgs;
608	struct net_device *vlandev;
609
610	if (dev->nd_net != &init_net)
611		return NOTIFY_DONE;
612
613	if (!grp)
614		goto out;
615
616	/* It is OK that we do not hold the group lock right now,
617	 * as we run under the RTNL lock.
618	 */
619
620	switch (event) {
621	case NETDEV_CHANGE:
622		/* Propagate real device state to vlan devices */
623		for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
624			vlandev = vlan_group_get_device(grp, i);
625			if (!vlandev)
626				continue;
627
628			vlan_transfer_operstate(dev, vlandev);
629		}
630		break;
631
632	case NETDEV_CHANGEADDR:
633		/* Adjust unicast filters on underlying device */
634		for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
635			vlandev = vlan_group_get_device(grp, i);
636			if (!vlandev)
637				continue;
638
639			flgs = vlandev->flags;
640			if (!(flgs & IFF_UP))
641				continue;
642
643			vlan_sync_address(dev, vlandev);
644		}
645		break;
646
647	case NETDEV_DOWN:
648		/* Put all VLANs for this dev in the down state too.  */
649		for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
650			vlandev = vlan_group_get_device(grp, i);
651			if (!vlandev)
652				continue;
653
654			flgs = vlandev->flags;
655			if (!(flgs & IFF_UP))
656				continue;
657
658			dev_change_flags(vlandev, flgs & ~IFF_UP);
659		}
660		break;
661
662	case NETDEV_UP:
663		/* Put all VLANs for this dev in the up state too.  */
664		for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
665			vlandev = vlan_group_get_device(grp, i);
666			if (!vlandev)
667				continue;
668
669			flgs = vlandev->flags;
670			if (flgs & IFF_UP)
671				continue;
672
673			dev_change_flags(vlandev, flgs | IFF_UP);
674		}
675		break;
676
677	case NETDEV_UNREGISTER:
678		/* Delete all VLANs for this dev. */
679		for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
680			int ret;
681
682			vlandev = vlan_group_get_device(grp, i);
683			if (!vlandev)
684				continue;
685
686			ret = unregister_vlan_dev(dev,
687						  VLAN_DEV_INFO(vlandev)->vlan_id);
688
689			unregister_netdevice(vlandev);
690
691			/* Group was destroyed? */
692			if (ret == 1)
693				break;
694		}
695		break;
696	}
697
698out:
699	return NOTIFY_DONE;
700}
701
702/*
703 *	VLAN IOCTL handler.
704 *	o execute requested action or pass command to the device driver
705 *   arg is really a struct vlan_ioctl_args __user *.
706 */
707static int vlan_ioctl_handler(struct net *net, void __user *arg)
708{
709	int err;
710	unsigned short vid = 0;
711	struct vlan_ioctl_args args;
712	struct net_device *dev = NULL;
713
714	if (copy_from_user(&args, arg, sizeof(struct vlan_ioctl_args)))
715		return -EFAULT;
716
717	/* Null terminate this sucker, just in case. */
718	args.device1[23] = 0;
719	args.u.device2[23] = 0;
720
721#ifdef VLAN_DEBUG
722	printk(VLAN_DBG "%s: args.cmd: %x\n", __FUNCTION__, args.cmd);
723#endif
724
725	rtnl_lock();
726
727	switch (args.cmd) {
728	case SET_VLAN_INGRESS_PRIORITY_CMD:
729	case SET_VLAN_EGRESS_PRIORITY_CMD:
730	case SET_VLAN_FLAG_CMD:
731	case ADD_VLAN_CMD:
732	case DEL_VLAN_CMD:
733	case GET_VLAN_REALDEV_NAME_CMD:
734	case GET_VLAN_VID_CMD:
735		err = -ENODEV;
736		dev = __dev_get_by_name(&init_net, args.device1);
737		if (!dev)
738			goto out;
739
740		err = -EINVAL;
741		if (args.cmd != ADD_VLAN_CMD &&
742		    !(dev->priv_flags & IFF_802_1Q_VLAN))
743			goto out;
744	}
745
746	switch (args.cmd) {
747	case SET_VLAN_INGRESS_PRIORITY_CMD:
748		err = -EPERM;
749		if (!capable(CAP_NET_ADMIN))
750			break;
751		vlan_dev_set_ingress_priority(dev,
752					      args.u.skb_priority,
753					      args.vlan_qos);
754		err = 0;
755		break;
756
757	case SET_VLAN_EGRESS_PRIORITY_CMD:
758		err = -EPERM;
759		if (!capable(CAP_NET_ADMIN))
760			break;
761		err = vlan_dev_set_egress_priority(dev,
762						   args.u.skb_priority,
763						   args.vlan_qos);
764		break;
765
766	case SET_VLAN_FLAG_CMD:
767		err = -EPERM;
768		if (!capable(CAP_NET_ADMIN))
769			break;
770		err = vlan_dev_set_vlan_flag(dev,
771					     args.u.flag,
772					     args.vlan_qos);
773		break;
774
775	case SET_VLAN_NAME_TYPE_CMD:
776		err = -EPERM;
777		if (!capable(CAP_NET_ADMIN))
778			return -EPERM;
779		if ((args.u.name_type >= 0) &&
780		    (args.u.name_type < VLAN_NAME_TYPE_HIGHEST)) {
781			vlan_name_type = args.u.name_type;
782			err = 0;
783		} else {
784			err = -EINVAL;
785		}
786		break;
787
788	case ADD_VLAN_CMD:
789		err = -EPERM;
790		if (!capable(CAP_NET_ADMIN))
791			break;
792		err = register_vlan_device(dev, args.u.VID);
793		break;
794
795	case DEL_VLAN_CMD:
796		err = -EPERM;
797		if (!capable(CAP_NET_ADMIN))
798			break;
799		err = unregister_vlan_device(dev);
800		break;
801
802	case GET_VLAN_INGRESS_PRIORITY_CMD:
803		/* TODO:  Implement
804		   err = vlan_dev_get_ingress_priority(args);
805		   if (copy_to_user((void*)arg, &args,
806			sizeof(struct vlan_ioctl_args))) {
807			err = -EFAULT;
808		   }
809		*/
810		err = -EINVAL;
811		break;
812	case GET_VLAN_EGRESS_PRIORITY_CMD:
813		/* TODO:  Implement
814		   err = vlan_dev_get_egress_priority(args.device1, &(args.args);
815		   if (copy_to_user((void*)arg, &args,
816			sizeof(struct vlan_ioctl_args))) {
817			err = -EFAULT;
818		   }
819		*/
820		err = -EINVAL;
821		break;
822	case GET_VLAN_REALDEV_NAME_CMD:
823		err = 0;
824		vlan_dev_get_realdev_name(dev, args.u.device2);
825		if (copy_to_user(arg, &args,
826				 sizeof(struct vlan_ioctl_args))) {
827			err = -EFAULT;
828		}
829		break;
830
831	case GET_VLAN_VID_CMD:
832		err = 0;
833		vlan_dev_get_vid(dev, &vid);
834		args.u.VID = vid;
835		if (copy_to_user(arg, &args,
836				 sizeof(struct vlan_ioctl_args))) {
837		      err = -EFAULT;
838		}
839		break;
840
841	default:
842		/* pass on to underlying device instead?? */
843		printk(VLAN_DBG "%s: Unknown VLAN CMD: %x \n",
844			__FUNCTION__, args.cmd);
845		err = -EINVAL;
846		break;
847	}
848out:
849	rtnl_unlock();
850	return err;
851}
852
853MODULE_LICENSE("GPL");
854MODULE_VERSION(DRV_VERSION);
855