xref: /openbmc/linux/net/8021q/vlan.c (revision 37185b33)
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: netdev@vger.kernel.org
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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22 
23 #include <linux/capability.h>
24 #include <linux/module.h>
25 #include <linux/netdevice.h>
26 #include <linux/skbuff.h>
27 #include <linux/slab.h>
28 #include <linux/init.h>
29 #include <linux/rculist.h>
30 #include <net/p8022.h>
31 #include <net/arp.h>
32 #include <linux/rtnetlink.h>
33 #include <linux/notifier.h>
34 #include <net/rtnetlink.h>
35 #include <net/net_namespace.h>
36 #include <net/netns/generic.h>
37 #include <asm/uaccess.h>
38 
39 #include <linux/if_vlan.h>
40 #include "vlan.h"
41 #include "vlanproc.h"
42 
43 #define DRV_VERSION "1.8"
44 
45 /* Global VLAN variables */
46 
47 int vlan_net_id __read_mostly;
48 
49 const char vlan_fullname[] = "802.1Q VLAN Support";
50 const char vlan_version[] = DRV_VERSION;
51 
52 /* End of global variables definitions. */
53 
54 static int vlan_group_prealloc_vid(struct vlan_group *vg, u16 vlan_id)
55 {
56 	struct net_device **array;
57 	unsigned int size;
58 
59 	ASSERT_RTNL();
60 
61 	array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
62 	if (array != NULL)
63 		return 0;
64 
65 	size = sizeof(struct net_device *) * VLAN_GROUP_ARRAY_PART_LEN;
66 	array = kzalloc(size, GFP_KERNEL);
67 	if (array == NULL)
68 		return -ENOBUFS;
69 
70 	vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN] = array;
71 	return 0;
72 }
73 
74 void unregister_vlan_dev(struct net_device *dev, struct list_head *head)
75 {
76 	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
77 	struct net_device *real_dev = vlan->real_dev;
78 	struct vlan_info *vlan_info;
79 	struct vlan_group *grp;
80 	u16 vlan_id = vlan->vlan_id;
81 
82 	ASSERT_RTNL();
83 
84 	vlan_info = rtnl_dereference(real_dev->vlan_info);
85 	BUG_ON(!vlan_info);
86 
87 	grp = &vlan_info->grp;
88 
89 	/* Take it out of our own structures, but be sure to interlock with
90 	 * HW accelerating devices or SW vlan input packet processing if
91 	 * VLAN is not 0 (leave it there for 802.1p).
92 	 */
93 	if (vlan_id)
94 		vlan_vid_del(real_dev, vlan_id);
95 
96 	grp->nr_vlan_devs--;
97 
98 	if (vlan->flags & VLAN_FLAG_GVRP)
99 		vlan_gvrp_request_leave(dev);
100 
101 	vlan_group_set_device(grp, vlan_id, NULL);
102 	/* Because unregister_netdevice_queue() makes sure at least one rcu
103 	 * grace period is respected before device freeing,
104 	 * we dont need to call synchronize_net() here.
105 	 */
106 	unregister_netdevice_queue(dev, head);
107 
108 	if (grp->nr_vlan_devs == 0)
109 		vlan_gvrp_uninit_applicant(real_dev);
110 
111 	/* Get rid of the vlan's reference to real_dev */
112 	dev_put(real_dev);
113 }
114 
115 int vlan_check_real_dev(struct net_device *real_dev, u16 vlan_id)
116 {
117 	const char *name = real_dev->name;
118 	const struct net_device_ops *ops = real_dev->netdev_ops;
119 
120 	if (real_dev->features & NETIF_F_VLAN_CHALLENGED) {
121 		pr_info("VLANs not supported on %s\n", name);
122 		return -EOPNOTSUPP;
123 	}
124 
125 	if ((real_dev->features & NETIF_F_HW_VLAN_FILTER) &&
126 	    (!ops->ndo_vlan_rx_add_vid || !ops->ndo_vlan_rx_kill_vid)) {
127 		pr_info("Device %s has buggy VLAN hw accel\n", name);
128 		return -EOPNOTSUPP;
129 	}
130 
131 	if (vlan_find_dev(real_dev, vlan_id) != NULL)
132 		return -EEXIST;
133 
134 	return 0;
135 }
136 
137 int register_vlan_dev(struct net_device *dev)
138 {
139 	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
140 	struct net_device *real_dev = vlan->real_dev;
141 	u16 vlan_id = vlan->vlan_id;
142 	struct vlan_info *vlan_info;
143 	struct vlan_group *grp;
144 	int err;
145 
146 	err = vlan_vid_add(real_dev, vlan_id);
147 	if (err)
148 		return err;
149 
150 	vlan_info = rtnl_dereference(real_dev->vlan_info);
151 	/* vlan_info should be there now. vlan_vid_add took care of it */
152 	BUG_ON(!vlan_info);
153 
154 	grp = &vlan_info->grp;
155 	if (grp->nr_vlan_devs == 0) {
156 		err = vlan_gvrp_init_applicant(real_dev);
157 		if (err < 0)
158 			goto out_vid_del;
159 	}
160 
161 	err = vlan_group_prealloc_vid(grp, vlan_id);
162 	if (err < 0)
163 		goto out_uninit_applicant;
164 
165 	err = register_netdevice(dev);
166 	if (err < 0)
167 		goto out_uninit_applicant;
168 
169 	/* Account for reference in struct vlan_dev_priv */
170 	dev_hold(real_dev);
171 
172 	netif_stacked_transfer_operstate(real_dev, dev);
173 	linkwatch_fire_event(dev); /* _MUST_ call rfc2863_policy() */
174 
175 	/* So, got the sucker initialized, now lets place
176 	 * it into our local structure.
177 	 */
178 	vlan_group_set_device(grp, vlan_id, dev);
179 	grp->nr_vlan_devs++;
180 
181 	return 0;
182 
183 out_uninit_applicant:
184 	if (grp->nr_vlan_devs == 0)
185 		vlan_gvrp_uninit_applicant(real_dev);
186 out_vid_del:
187 	vlan_vid_del(real_dev, vlan_id);
188 	return err;
189 }
190 
191 /*  Attach a VLAN device to a mac address (ie Ethernet Card).
192  *  Returns 0 if the device was created or a negative error code otherwise.
193  */
194 static int register_vlan_device(struct net_device *real_dev, u16 vlan_id)
195 {
196 	struct net_device *new_dev;
197 	struct net *net = dev_net(real_dev);
198 	struct vlan_net *vn = net_generic(net, vlan_net_id);
199 	char name[IFNAMSIZ];
200 	int err;
201 
202 	if (vlan_id >= VLAN_VID_MASK)
203 		return -ERANGE;
204 
205 	err = vlan_check_real_dev(real_dev, vlan_id);
206 	if (err < 0)
207 		return err;
208 
209 	/* Gotta set up the fields for the device. */
210 	switch (vn->name_type) {
211 	case VLAN_NAME_TYPE_RAW_PLUS_VID:
212 		/* name will look like:	 eth1.0005 */
213 		snprintf(name, IFNAMSIZ, "%s.%.4i", real_dev->name, vlan_id);
214 		break;
215 	case VLAN_NAME_TYPE_PLUS_VID_NO_PAD:
216 		/* Put our vlan.VID in the name.
217 		 * Name will look like:	 vlan5
218 		 */
219 		snprintf(name, IFNAMSIZ, "vlan%i", vlan_id);
220 		break;
221 	case VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD:
222 		/* Put our vlan.VID in the name.
223 		 * Name will look like:	 eth0.5
224 		 */
225 		snprintf(name, IFNAMSIZ, "%s.%i", real_dev->name, vlan_id);
226 		break;
227 	case VLAN_NAME_TYPE_PLUS_VID:
228 		/* Put our vlan.VID in the name.
229 		 * Name will look like:	 vlan0005
230 		 */
231 	default:
232 		snprintf(name, IFNAMSIZ, "vlan%.4i", vlan_id);
233 	}
234 
235 	new_dev = alloc_netdev(sizeof(struct vlan_dev_priv), name, vlan_setup);
236 
237 	if (new_dev == NULL)
238 		return -ENOBUFS;
239 
240 	dev_net_set(new_dev, net);
241 	/* need 4 bytes for extra VLAN header info,
242 	 * hope the underlying device can handle it.
243 	 */
244 	new_dev->mtu = real_dev->mtu;
245 
246 	vlan_dev_priv(new_dev)->vlan_id = vlan_id;
247 	vlan_dev_priv(new_dev)->real_dev = real_dev;
248 	vlan_dev_priv(new_dev)->dent = NULL;
249 	vlan_dev_priv(new_dev)->flags = VLAN_FLAG_REORDER_HDR;
250 
251 	new_dev->rtnl_link_ops = &vlan_link_ops;
252 	err = register_vlan_dev(new_dev);
253 	if (err < 0)
254 		goto out_free_newdev;
255 
256 	return 0;
257 
258 out_free_newdev:
259 	free_netdev(new_dev);
260 	return err;
261 }
262 
263 static void vlan_sync_address(struct net_device *dev,
264 			      struct net_device *vlandev)
265 {
266 	struct vlan_dev_priv *vlan = vlan_dev_priv(vlandev);
267 
268 	/* May be called without an actual change */
269 	if (ether_addr_equal(vlan->real_dev_addr, dev->dev_addr))
270 		return;
271 
272 	/* vlan address was different from the old address and is equal to
273 	 * the new address */
274 	if (!ether_addr_equal(vlandev->dev_addr, vlan->real_dev_addr) &&
275 	    ether_addr_equal(vlandev->dev_addr, dev->dev_addr))
276 		dev_uc_del(dev, vlandev->dev_addr);
277 
278 	/* vlan address was equal to the old address and is different from
279 	 * the new address */
280 	if (ether_addr_equal(vlandev->dev_addr, vlan->real_dev_addr) &&
281 	    !ether_addr_equal(vlandev->dev_addr, dev->dev_addr))
282 		dev_uc_add(dev, vlandev->dev_addr);
283 
284 	memcpy(vlan->real_dev_addr, dev->dev_addr, ETH_ALEN);
285 }
286 
287 static void vlan_transfer_features(struct net_device *dev,
288 				   struct net_device *vlandev)
289 {
290 	vlandev->gso_max_size = dev->gso_max_size;
291 
292 	if (dev->features & NETIF_F_HW_VLAN_TX)
293 		vlandev->hard_header_len = dev->hard_header_len;
294 	else
295 		vlandev->hard_header_len = dev->hard_header_len + VLAN_HLEN;
296 
297 #if defined(CONFIG_FCOE) || defined(CONFIG_FCOE_MODULE)
298 	vlandev->fcoe_ddp_xid = dev->fcoe_ddp_xid;
299 #endif
300 
301 	netdev_update_features(vlandev);
302 }
303 
304 static void __vlan_device_event(struct net_device *dev, unsigned long event)
305 {
306 	switch (event) {
307 	case NETDEV_CHANGENAME:
308 		vlan_proc_rem_dev(dev);
309 		if (vlan_proc_add_dev(dev) < 0)
310 			pr_warn("failed to change proc name for %s\n",
311 				dev->name);
312 		break;
313 	case NETDEV_REGISTER:
314 		if (vlan_proc_add_dev(dev) < 0)
315 			pr_warn("failed to add proc entry for %s\n", dev->name);
316 		break;
317 	case NETDEV_UNREGISTER:
318 		vlan_proc_rem_dev(dev);
319 		break;
320 	}
321 }
322 
323 static int vlan_device_event(struct notifier_block *unused, unsigned long event,
324 			     void *ptr)
325 {
326 	struct net_device *dev = ptr;
327 	struct vlan_group *grp;
328 	struct vlan_info *vlan_info;
329 	int i, flgs;
330 	struct net_device *vlandev;
331 	struct vlan_dev_priv *vlan;
332 	LIST_HEAD(list);
333 
334 	if (is_vlan_dev(dev))
335 		__vlan_device_event(dev, event);
336 
337 	if ((event == NETDEV_UP) &&
338 	    (dev->features & NETIF_F_HW_VLAN_FILTER)) {
339 		pr_info("adding VLAN 0 to HW filter on device %s\n",
340 			dev->name);
341 		vlan_vid_add(dev, 0);
342 	}
343 
344 	vlan_info = rtnl_dereference(dev->vlan_info);
345 	if (!vlan_info)
346 		goto out;
347 	grp = &vlan_info->grp;
348 
349 	/* It is OK that we do not hold the group lock right now,
350 	 * as we run under the RTNL lock.
351 	 */
352 
353 	switch (event) {
354 	case NETDEV_CHANGE:
355 		/* Propagate real device state to vlan devices */
356 		for (i = 0; i < VLAN_N_VID; i++) {
357 			vlandev = vlan_group_get_device(grp, i);
358 			if (!vlandev)
359 				continue;
360 
361 			netif_stacked_transfer_operstate(dev, vlandev);
362 		}
363 		break;
364 
365 	case NETDEV_CHANGEADDR:
366 		/* Adjust unicast filters on underlying device */
367 		for (i = 0; i < VLAN_N_VID; i++) {
368 			vlandev = vlan_group_get_device(grp, i);
369 			if (!vlandev)
370 				continue;
371 
372 			flgs = vlandev->flags;
373 			if (!(flgs & IFF_UP))
374 				continue;
375 
376 			vlan_sync_address(dev, vlandev);
377 		}
378 		break;
379 
380 	case NETDEV_CHANGEMTU:
381 		for (i = 0; i < VLAN_N_VID; i++) {
382 			vlandev = vlan_group_get_device(grp, i);
383 			if (!vlandev)
384 				continue;
385 
386 			if (vlandev->mtu <= dev->mtu)
387 				continue;
388 
389 			dev_set_mtu(vlandev, dev->mtu);
390 		}
391 		break;
392 
393 	case NETDEV_FEAT_CHANGE:
394 		/* Propagate device features to underlying device */
395 		for (i = 0; i < VLAN_N_VID; i++) {
396 			vlandev = vlan_group_get_device(grp, i);
397 			if (!vlandev)
398 				continue;
399 
400 			vlan_transfer_features(dev, vlandev);
401 		}
402 
403 		break;
404 
405 	case NETDEV_DOWN:
406 		if (dev->features & NETIF_F_HW_VLAN_FILTER)
407 			vlan_vid_del(dev, 0);
408 
409 		/* Put all VLANs for this dev in the down state too.  */
410 		for (i = 0; i < VLAN_N_VID; i++) {
411 			vlandev = vlan_group_get_device(grp, i);
412 			if (!vlandev)
413 				continue;
414 
415 			flgs = vlandev->flags;
416 			if (!(flgs & IFF_UP))
417 				continue;
418 
419 			vlan = vlan_dev_priv(vlandev);
420 			if (!(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
421 				dev_change_flags(vlandev, flgs & ~IFF_UP);
422 			netif_stacked_transfer_operstate(dev, vlandev);
423 		}
424 		break;
425 
426 	case NETDEV_UP:
427 		/* Put all VLANs for this dev in the up state too.  */
428 		for (i = 0; i < VLAN_N_VID; i++) {
429 			vlandev = vlan_group_get_device(grp, i);
430 			if (!vlandev)
431 				continue;
432 
433 			flgs = vlandev->flags;
434 			if (flgs & IFF_UP)
435 				continue;
436 
437 			vlan = vlan_dev_priv(vlandev);
438 			if (!(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
439 				dev_change_flags(vlandev, flgs | IFF_UP);
440 			netif_stacked_transfer_operstate(dev, vlandev);
441 		}
442 		break;
443 
444 	case NETDEV_UNREGISTER:
445 		/* twiddle thumbs on netns device moves */
446 		if (dev->reg_state != NETREG_UNREGISTERING)
447 			break;
448 
449 		for (i = 0; i < VLAN_N_VID; i++) {
450 			vlandev = vlan_group_get_device(grp, i);
451 			if (!vlandev)
452 				continue;
453 
454 			/* removal of last vid destroys vlan_info, abort
455 			 * afterwards */
456 			if (vlan_info->nr_vids == 1)
457 				i = VLAN_N_VID;
458 
459 			unregister_vlan_dev(vlandev, &list);
460 		}
461 		unregister_netdevice_many(&list);
462 		break;
463 
464 	case NETDEV_PRE_TYPE_CHANGE:
465 		/* Forbid underlaying device to change its type. */
466 		return NOTIFY_BAD;
467 
468 	case NETDEV_NOTIFY_PEERS:
469 	case NETDEV_BONDING_FAILOVER:
470 		/* Propagate to vlan devices */
471 		for (i = 0; i < VLAN_N_VID; i++) {
472 			vlandev = vlan_group_get_device(grp, i);
473 			if (!vlandev)
474 				continue;
475 
476 			call_netdevice_notifiers(event, vlandev);
477 		}
478 		break;
479 	}
480 
481 out:
482 	return NOTIFY_DONE;
483 }
484 
485 static struct notifier_block vlan_notifier_block __read_mostly = {
486 	.notifier_call = vlan_device_event,
487 };
488 
489 /*
490  *	VLAN IOCTL handler.
491  *	o execute requested action or pass command to the device driver
492  *   arg is really a struct vlan_ioctl_args __user *.
493  */
494 static int vlan_ioctl_handler(struct net *net, void __user *arg)
495 {
496 	int err;
497 	struct vlan_ioctl_args args;
498 	struct net_device *dev = NULL;
499 
500 	if (copy_from_user(&args, arg, sizeof(struct vlan_ioctl_args)))
501 		return -EFAULT;
502 
503 	/* Null terminate this sucker, just in case. */
504 	args.device1[23] = 0;
505 	args.u.device2[23] = 0;
506 
507 	rtnl_lock();
508 
509 	switch (args.cmd) {
510 	case SET_VLAN_INGRESS_PRIORITY_CMD:
511 	case SET_VLAN_EGRESS_PRIORITY_CMD:
512 	case SET_VLAN_FLAG_CMD:
513 	case ADD_VLAN_CMD:
514 	case DEL_VLAN_CMD:
515 	case GET_VLAN_REALDEV_NAME_CMD:
516 	case GET_VLAN_VID_CMD:
517 		err = -ENODEV;
518 		dev = __dev_get_by_name(net, args.device1);
519 		if (!dev)
520 			goto out;
521 
522 		err = -EINVAL;
523 		if (args.cmd != ADD_VLAN_CMD && !is_vlan_dev(dev))
524 			goto out;
525 	}
526 
527 	switch (args.cmd) {
528 	case SET_VLAN_INGRESS_PRIORITY_CMD:
529 		err = -EPERM;
530 		if (!capable(CAP_NET_ADMIN))
531 			break;
532 		vlan_dev_set_ingress_priority(dev,
533 					      args.u.skb_priority,
534 					      args.vlan_qos);
535 		err = 0;
536 		break;
537 
538 	case SET_VLAN_EGRESS_PRIORITY_CMD:
539 		err = -EPERM;
540 		if (!capable(CAP_NET_ADMIN))
541 			break;
542 		err = vlan_dev_set_egress_priority(dev,
543 						   args.u.skb_priority,
544 						   args.vlan_qos);
545 		break;
546 
547 	case SET_VLAN_FLAG_CMD:
548 		err = -EPERM;
549 		if (!capable(CAP_NET_ADMIN))
550 			break;
551 		err = vlan_dev_change_flags(dev,
552 					    args.vlan_qos ? args.u.flag : 0,
553 					    args.u.flag);
554 		break;
555 
556 	case SET_VLAN_NAME_TYPE_CMD:
557 		err = -EPERM;
558 		if (!capable(CAP_NET_ADMIN))
559 			break;
560 		if ((args.u.name_type >= 0) &&
561 		    (args.u.name_type < VLAN_NAME_TYPE_HIGHEST)) {
562 			struct vlan_net *vn;
563 
564 			vn = net_generic(net, vlan_net_id);
565 			vn->name_type = args.u.name_type;
566 			err = 0;
567 		} else {
568 			err = -EINVAL;
569 		}
570 		break;
571 
572 	case ADD_VLAN_CMD:
573 		err = -EPERM;
574 		if (!capable(CAP_NET_ADMIN))
575 			break;
576 		err = register_vlan_device(dev, args.u.VID);
577 		break;
578 
579 	case DEL_VLAN_CMD:
580 		err = -EPERM;
581 		if (!capable(CAP_NET_ADMIN))
582 			break;
583 		unregister_vlan_dev(dev, NULL);
584 		err = 0;
585 		break;
586 
587 	case GET_VLAN_REALDEV_NAME_CMD:
588 		err = 0;
589 		vlan_dev_get_realdev_name(dev, args.u.device2);
590 		if (copy_to_user(arg, &args,
591 				 sizeof(struct vlan_ioctl_args)))
592 			err = -EFAULT;
593 		break;
594 
595 	case GET_VLAN_VID_CMD:
596 		err = 0;
597 		args.u.VID = vlan_dev_vlan_id(dev);
598 		if (copy_to_user(arg, &args,
599 				 sizeof(struct vlan_ioctl_args)))
600 		      err = -EFAULT;
601 		break;
602 
603 	default:
604 		err = -EOPNOTSUPP;
605 		break;
606 	}
607 out:
608 	rtnl_unlock();
609 	return err;
610 }
611 
612 static int __net_init vlan_init_net(struct net *net)
613 {
614 	struct vlan_net *vn = net_generic(net, vlan_net_id);
615 	int err;
616 
617 	vn->name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD;
618 
619 	err = vlan_proc_init(net);
620 
621 	return err;
622 }
623 
624 static void __net_exit vlan_exit_net(struct net *net)
625 {
626 	vlan_proc_cleanup(net);
627 }
628 
629 static struct pernet_operations vlan_net_ops = {
630 	.init = vlan_init_net,
631 	.exit = vlan_exit_net,
632 	.id   = &vlan_net_id,
633 	.size = sizeof(struct vlan_net),
634 };
635 
636 static int __init vlan_proto_init(void)
637 {
638 	int err;
639 
640 	pr_info("%s v%s\n", vlan_fullname, vlan_version);
641 
642 	err = register_pernet_subsys(&vlan_net_ops);
643 	if (err < 0)
644 		goto err0;
645 
646 	err = register_netdevice_notifier(&vlan_notifier_block);
647 	if (err < 0)
648 		goto err2;
649 
650 	err = vlan_gvrp_init();
651 	if (err < 0)
652 		goto err3;
653 
654 	err = vlan_netlink_init();
655 	if (err < 0)
656 		goto err4;
657 
658 	vlan_ioctl_set(vlan_ioctl_handler);
659 	return 0;
660 
661 err4:
662 	vlan_gvrp_uninit();
663 err3:
664 	unregister_netdevice_notifier(&vlan_notifier_block);
665 err2:
666 	unregister_pernet_subsys(&vlan_net_ops);
667 err0:
668 	return err;
669 }
670 
671 static void __exit vlan_cleanup_module(void)
672 {
673 	vlan_ioctl_set(NULL);
674 	vlan_netlink_fini();
675 
676 	unregister_netdevice_notifier(&vlan_notifier_block);
677 
678 	unregister_pernet_subsys(&vlan_net_ops);
679 	rcu_barrier(); /* Wait for completion of call_rcu()'s */
680 
681 	vlan_gvrp_uninit();
682 }
683 
684 module_init(vlan_proto_init);
685 module_exit(vlan_cleanup_module);
686 
687 MODULE_LICENSE("GPL");
688 MODULE_VERSION(DRV_VERSION);
689