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
vlan_group_prealloc_vid(struct vlan_group * vg,__be16 vlan_proto,u16 vlan_id)54 static int vlan_group_prealloc_vid(struct vlan_group *vg,
55 __be16 vlan_proto, u16 vlan_id)
56 {
57 struct net_device **array;
58 unsigned int pidx, vidx;
59 unsigned int size;
60
61 ASSERT_RTNL();
62
63 pidx = vlan_proto_idx(vlan_proto);
64 vidx = vlan_id / VLAN_GROUP_ARRAY_PART_LEN;
65 array = vg->vlan_devices_arrays[pidx][vidx];
66 if (array != NULL)
67 return 0;
68
69 size = sizeof(struct net_device *) * VLAN_GROUP_ARRAY_PART_LEN;
70 array = kzalloc(size, GFP_KERNEL);
71 if (array == NULL)
72 return -ENOBUFS;
73
74 vg->vlan_devices_arrays[pidx][vidx] = array;
75 return 0;
76 }
77
unregister_vlan_dev(struct net_device * dev,struct list_head * head)78 void unregister_vlan_dev(struct net_device *dev, struct list_head *head)
79 {
80 struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
81 struct net_device *real_dev = vlan->real_dev;
82 struct vlan_info *vlan_info;
83 struct vlan_group *grp;
84 u16 vlan_id = vlan->vlan_id;
85
86 ASSERT_RTNL();
87
88 vlan_info = rtnl_dereference(real_dev->vlan_info);
89 BUG_ON(!vlan_info);
90
91 grp = &vlan_info->grp;
92
93 grp->nr_vlan_devs--;
94
95 if (vlan->flags & VLAN_FLAG_MVRP)
96 vlan_mvrp_request_leave(dev);
97 if (vlan->flags & VLAN_FLAG_GVRP)
98 vlan_gvrp_request_leave(dev);
99
100 vlan_group_set_device(grp, vlan->vlan_proto, vlan_id, NULL);
101 /* Because unregister_netdevice_queue() makes sure at least one rcu
102 * grace period is respected before device freeing,
103 * we dont need to call synchronize_net() here.
104 */
105 unregister_netdevice_queue(dev, head);
106
107 netdev_upper_dev_unlink(real_dev, dev);
108
109 if (grp->nr_vlan_devs == 0) {
110 vlan_mvrp_uninit_applicant(real_dev);
111 vlan_gvrp_uninit_applicant(real_dev);
112 }
113
114 /* Take it out of our own structures, but be sure to interlock with
115 * HW accelerating devices or SW vlan input packet processing if
116 * VLAN is not 0 (leave it there for 802.1p).
117 */
118 if (vlan_id)
119 vlan_vid_del(real_dev, vlan->vlan_proto, vlan_id);
120
121 /* Get rid of the vlan's reference to real_dev */
122 dev_put(real_dev);
123 }
124
vlan_check_real_dev(struct net_device * real_dev,__be16 protocol,u16 vlan_id)125 int vlan_check_real_dev(struct net_device *real_dev,
126 __be16 protocol, u16 vlan_id)
127 {
128 const char *name = real_dev->name;
129
130 if (real_dev->features & NETIF_F_VLAN_CHALLENGED) {
131 pr_info("VLANs not supported on %s\n", name);
132 return -EOPNOTSUPP;
133 }
134
135 if (vlan_find_dev(real_dev, protocol, vlan_id) != NULL)
136 return -EEXIST;
137
138 return 0;
139 }
140
register_vlan_dev(struct net_device * dev)141 int register_vlan_dev(struct net_device *dev)
142 {
143 struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
144 struct net_device *real_dev = vlan->real_dev;
145 u16 vlan_id = vlan->vlan_id;
146 struct vlan_info *vlan_info;
147 struct vlan_group *grp;
148 int err;
149
150 err = vlan_vid_add(real_dev, vlan->vlan_proto, vlan_id);
151 if (err)
152 return err;
153
154 vlan_info = rtnl_dereference(real_dev->vlan_info);
155 /* vlan_info should be there now. vlan_vid_add took care of it */
156 BUG_ON(!vlan_info);
157
158 grp = &vlan_info->grp;
159 if (grp->nr_vlan_devs == 0) {
160 err = vlan_gvrp_init_applicant(real_dev);
161 if (err < 0)
162 goto out_vid_del;
163 err = vlan_mvrp_init_applicant(real_dev);
164 if (err < 0)
165 goto out_uninit_gvrp;
166 }
167
168 err = vlan_group_prealloc_vid(grp, vlan->vlan_proto, vlan_id);
169 if (err < 0)
170 goto out_uninit_mvrp;
171
172 err = netdev_upper_dev_link(real_dev, dev);
173 if (err)
174 goto out_uninit_mvrp;
175
176 err = register_netdevice(dev);
177 if (err < 0)
178 goto out_upper_dev_unlink;
179
180 /* Account for reference in struct vlan_dev_priv */
181 dev_hold(real_dev);
182
183 netif_stacked_transfer_operstate(real_dev, dev);
184 linkwatch_fire_event(dev); /* _MUST_ call rfc2863_policy() */
185
186 /* So, got the sucker initialized, now lets place
187 * it into our local structure.
188 */
189 vlan_group_set_device(grp, vlan->vlan_proto, vlan_id, dev);
190 grp->nr_vlan_devs++;
191
192 return 0;
193
194 out_upper_dev_unlink:
195 netdev_upper_dev_unlink(real_dev, dev);
196 out_uninit_mvrp:
197 if (grp->nr_vlan_devs == 0)
198 vlan_mvrp_uninit_applicant(real_dev);
199 out_uninit_gvrp:
200 if (grp->nr_vlan_devs == 0)
201 vlan_gvrp_uninit_applicant(real_dev);
202 out_vid_del:
203 vlan_vid_del(real_dev, vlan->vlan_proto, vlan_id);
204 return err;
205 }
206
207 /* Attach a VLAN device to a mac address (ie Ethernet Card).
208 * Returns 0 if the device was created or a negative error code otherwise.
209 */
register_vlan_device(struct net_device * real_dev,u16 vlan_id)210 static int register_vlan_device(struct net_device *real_dev, u16 vlan_id)
211 {
212 struct net_device *new_dev;
213 struct net *net = dev_net(real_dev);
214 struct vlan_net *vn = net_generic(net, vlan_net_id);
215 char name[IFNAMSIZ];
216 int err;
217
218 if (vlan_id >= VLAN_VID_MASK)
219 return -ERANGE;
220
221 err = vlan_check_real_dev(real_dev, htons(ETH_P_8021Q), vlan_id);
222 if (err < 0)
223 return err;
224
225 /* Gotta set up the fields for the device. */
226 switch (vn->name_type) {
227 case VLAN_NAME_TYPE_RAW_PLUS_VID:
228 /* name will look like: eth1.0005 */
229 snprintf(name, IFNAMSIZ, "%s.%.4i", real_dev->name, vlan_id);
230 break;
231 case VLAN_NAME_TYPE_PLUS_VID_NO_PAD:
232 /* Put our vlan.VID in the name.
233 * Name will look like: vlan5
234 */
235 snprintf(name, IFNAMSIZ, "vlan%i", vlan_id);
236 break;
237 case VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD:
238 /* Put our vlan.VID in the name.
239 * Name will look like: eth0.5
240 */
241 snprintf(name, IFNAMSIZ, "%s.%i", real_dev->name, vlan_id);
242 break;
243 case VLAN_NAME_TYPE_PLUS_VID:
244 /* Put our vlan.VID in the name.
245 * Name will look like: vlan0005
246 */
247 default:
248 snprintf(name, IFNAMSIZ, "vlan%.4i", vlan_id);
249 }
250
251 new_dev = alloc_netdev(sizeof(struct vlan_dev_priv), name, vlan_setup);
252
253 if (new_dev == NULL)
254 return -ENOBUFS;
255
256 dev_net_set(new_dev, net);
257 /* need 4 bytes for extra VLAN header info,
258 * hope the underlying device can handle it.
259 */
260 new_dev->mtu = real_dev->mtu;
261 new_dev->priv_flags |= (real_dev->priv_flags & IFF_UNICAST_FLT);
262
263 vlan_dev_priv(new_dev)->vlan_proto = htons(ETH_P_8021Q);
264 vlan_dev_priv(new_dev)->vlan_id = vlan_id;
265 vlan_dev_priv(new_dev)->real_dev = real_dev;
266 vlan_dev_priv(new_dev)->dent = NULL;
267 vlan_dev_priv(new_dev)->flags = VLAN_FLAG_REORDER_HDR;
268
269 new_dev->rtnl_link_ops = &vlan_link_ops;
270 err = register_vlan_dev(new_dev);
271 if (err < 0)
272 goto out_free_newdev;
273
274 return 0;
275
276 out_free_newdev:
277 free_netdev(new_dev);
278 return err;
279 }
280
vlan_sync_address(struct net_device * dev,struct net_device * vlandev)281 static void vlan_sync_address(struct net_device *dev,
282 struct net_device *vlandev)
283 {
284 struct vlan_dev_priv *vlan = vlan_dev_priv(vlandev);
285
286 /* May be called without an actual change */
287 if (ether_addr_equal(vlan->real_dev_addr, dev->dev_addr))
288 return;
289
290 /* vlan address was different from the old address and is equal to
291 * the new address */
292 if (!ether_addr_equal(vlandev->dev_addr, vlan->real_dev_addr) &&
293 ether_addr_equal(vlandev->dev_addr, dev->dev_addr))
294 dev_uc_del(dev, vlandev->dev_addr);
295
296 /* vlan address was equal to the old address and is different from
297 * the new address */
298 if (ether_addr_equal(vlandev->dev_addr, vlan->real_dev_addr) &&
299 !ether_addr_equal(vlandev->dev_addr, dev->dev_addr))
300 dev_uc_add(dev, vlandev->dev_addr);
301
302 memcpy(vlan->real_dev_addr, dev->dev_addr, ETH_ALEN);
303 }
304
vlan_transfer_features(struct net_device * dev,struct net_device * vlandev)305 static void vlan_transfer_features(struct net_device *dev,
306 struct net_device *vlandev)
307 {
308 vlandev->gso_max_size = dev->gso_max_size;
309
310 if (dev->features & NETIF_F_HW_VLAN_CTAG_TX)
311 vlandev->hard_header_len = dev->hard_header_len;
312 else
313 vlandev->hard_header_len = dev->hard_header_len + VLAN_HLEN;
314
315 #if IS_ENABLED(CONFIG_FCOE)
316 vlandev->fcoe_ddp_xid = dev->fcoe_ddp_xid;
317 #endif
318
319 netdev_update_features(vlandev);
320 }
321
__vlan_device_event(struct net_device * dev,unsigned long event)322 static void __vlan_device_event(struct net_device *dev, unsigned long event)
323 {
324 switch (event) {
325 case NETDEV_CHANGENAME:
326 vlan_proc_rem_dev(dev);
327 if (vlan_proc_add_dev(dev) < 0)
328 pr_warn("failed to change proc name for %s\n",
329 dev->name);
330 break;
331 case NETDEV_REGISTER:
332 if (vlan_proc_add_dev(dev) < 0)
333 pr_warn("failed to add proc entry for %s\n", dev->name);
334 break;
335 case NETDEV_UNREGISTER:
336 vlan_proc_rem_dev(dev);
337 break;
338 }
339 }
340
vlan_device_event(struct notifier_block * unused,unsigned long event,void * ptr)341 static int vlan_device_event(struct notifier_block *unused, unsigned long event,
342 void *ptr)
343 {
344 struct net_device *dev = ptr;
345 struct vlan_group *grp;
346 struct vlan_info *vlan_info;
347 int i, flgs;
348 struct net_device *vlandev;
349 struct vlan_dev_priv *vlan;
350 bool last = false;
351 LIST_HEAD(list);
352
353 if (is_vlan_dev(dev))
354 __vlan_device_event(dev, event);
355
356 if ((event == NETDEV_UP) &&
357 (dev->features & NETIF_F_HW_VLAN_CTAG_FILTER)) {
358 pr_info("adding VLAN 0 to HW filter on device %s\n",
359 dev->name);
360 vlan_vid_add(dev, htons(ETH_P_8021Q), 0);
361 }
362
363 vlan_info = rtnl_dereference(dev->vlan_info);
364 if (!vlan_info)
365 goto out;
366 grp = &vlan_info->grp;
367
368 /* It is OK that we do not hold the group lock right now,
369 * as we run under the RTNL lock.
370 */
371
372 switch (event) {
373 case NETDEV_CHANGE:
374 /* Propagate real device state to vlan devices */
375 vlan_group_for_each_dev(grp, i, vlandev)
376 netif_stacked_transfer_operstate(dev, vlandev);
377 break;
378
379 case NETDEV_CHANGEADDR:
380 /* Adjust unicast filters on underlying device */
381 vlan_group_for_each_dev(grp, i, vlandev) {
382 flgs = vlandev->flags;
383 if (!(flgs & IFF_UP))
384 continue;
385
386 vlan_sync_address(dev, vlandev);
387 }
388 break;
389
390 case NETDEV_CHANGEMTU:
391 vlan_group_for_each_dev(grp, i, vlandev) {
392 if (vlandev->mtu <= dev->mtu)
393 continue;
394
395 dev_set_mtu(vlandev, dev->mtu);
396 }
397 break;
398
399 case NETDEV_FEAT_CHANGE:
400 /* Propagate device features to underlying device */
401 vlan_group_for_each_dev(grp, i, vlandev)
402 vlan_transfer_features(dev, vlandev);
403 break;
404
405 case NETDEV_DOWN:
406 if (dev->features & NETIF_F_HW_VLAN_CTAG_FILTER)
407 vlan_vid_del(dev, htons(ETH_P_8021Q), 0);
408
409 /* Put all VLANs for this dev in the down state too. */
410 vlan_group_for_each_dev(grp, i, vlandev) {
411 flgs = vlandev->flags;
412 if (!(flgs & IFF_UP))
413 continue;
414
415 vlan = vlan_dev_priv(vlandev);
416 if (!(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
417 dev_change_flags(vlandev, flgs & ~IFF_UP);
418 netif_stacked_transfer_operstate(dev, vlandev);
419 }
420 break;
421
422 case NETDEV_UP:
423 /* Put all VLANs for this dev in the up state too. */
424 vlan_group_for_each_dev(grp, i, vlandev) {
425 flgs = vlandev->flags;
426 if (flgs & IFF_UP)
427 continue;
428
429 vlan = vlan_dev_priv(vlandev);
430 if (!(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
431 dev_change_flags(vlandev, flgs | IFF_UP);
432 netif_stacked_transfer_operstate(dev, vlandev);
433 }
434 break;
435
436 case NETDEV_UNREGISTER:
437 /* twiddle thumbs on netns device moves */
438 if (dev->reg_state != NETREG_UNREGISTERING)
439 break;
440
441 vlan_group_for_each_dev(grp, i, vlandev) {
442 /* removal of last vid destroys vlan_info, abort
443 * afterwards */
444 if (vlan_info->nr_vids == 1)
445 last = true;
446
447 unregister_vlan_dev(vlandev, &list);
448 if (last)
449 break;
450 }
451 unregister_netdevice_many(&list);
452 break;
453
454 case NETDEV_PRE_TYPE_CHANGE:
455 /* Forbid underlaying device to change its type. */
456 if (vlan_uses_dev(dev))
457 return NOTIFY_BAD;
458 break;
459
460 case NETDEV_NOTIFY_PEERS:
461 case NETDEV_BONDING_FAILOVER:
462 /* Propagate to vlan devices */
463 vlan_group_for_each_dev(grp, i, vlandev)
464 call_netdevice_notifiers(event, vlandev);
465 break;
466 }
467
468 out:
469 return NOTIFY_DONE;
470 }
471
472 static struct notifier_block vlan_notifier_block __read_mostly = {
473 .notifier_call = vlan_device_event,
474 };
475
476 /*
477 * VLAN IOCTL handler.
478 * o execute requested action or pass command to the device driver
479 * arg is really a struct vlan_ioctl_args __user *.
480 */
vlan_ioctl_handler(struct net * net,void __user * arg)481 static int vlan_ioctl_handler(struct net *net, void __user *arg)
482 {
483 int err;
484 struct vlan_ioctl_args args;
485 struct net_device *dev = NULL;
486
487 if (copy_from_user(&args, arg, sizeof(struct vlan_ioctl_args)))
488 return -EFAULT;
489
490 /* Null terminate this sucker, just in case. */
491 args.device1[23] = 0;
492 args.u.device2[23] = 0;
493
494 rtnl_lock();
495
496 switch (args.cmd) {
497 case SET_VLAN_INGRESS_PRIORITY_CMD:
498 case SET_VLAN_EGRESS_PRIORITY_CMD:
499 case SET_VLAN_FLAG_CMD:
500 case ADD_VLAN_CMD:
501 case DEL_VLAN_CMD:
502 case GET_VLAN_REALDEV_NAME_CMD:
503 case GET_VLAN_VID_CMD:
504 err = -ENODEV;
505 dev = __dev_get_by_name(net, args.device1);
506 if (!dev)
507 goto out;
508
509 err = -EINVAL;
510 if (args.cmd != ADD_VLAN_CMD && !is_vlan_dev(dev))
511 goto out;
512 }
513
514 switch (args.cmd) {
515 case SET_VLAN_INGRESS_PRIORITY_CMD:
516 err = -EPERM;
517 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
518 break;
519 vlan_dev_set_ingress_priority(dev,
520 args.u.skb_priority,
521 args.vlan_qos);
522 err = 0;
523 break;
524
525 case SET_VLAN_EGRESS_PRIORITY_CMD:
526 err = -EPERM;
527 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
528 break;
529 err = vlan_dev_set_egress_priority(dev,
530 args.u.skb_priority,
531 args.vlan_qos);
532 break;
533
534 case SET_VLAN_FLAG_CMD:
535 err = -EPERM;
536 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
537 break;
538 err = vlan_dev_change_flags(dev,
539 args.vlan_qos ? args.u.flag : 0,
540 args.u.flag);
541 break;
542
543 case SET_VLAN_NAME_TYPE_CMD:
544 err = -EPERM;
545 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
546 break;
547 if ((args.u.name_type >= 0) &&
548 (args.u.name_type < VLAN_NAME_TYPE_HIGHEST)) {
549 struct vlan_net *vn;
550
551 vn = net_generic(net, vlan_net_id);
552 vn->name_type = args.u.name_type;
553 err = 0;
554 } else {
555 err = -EINVAL;
556 }
557 break;
558
559 case ADD_VLAN_CMD:
560 err = -EPERM;
561 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
562 break;
563 err = register_vlan_device(dev, args.u.VID);
564 break;
565
566 case DEL_VLAN_CMD:
567 err = -EPERM;
568 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
569 break;
570 unregister_vlan_dev(dev, NULL);
571 err = 0;
572 break;
573
574 case GET_VLAN_REALDEV_NAME_CMD:
575 err = 0;
576 vlan_dev_get_realdev_name(dev, args.u.device2);
577 if (copy_to_user(arg, &args,
578 sizeof(struct vlan_ioctl_args)))
579 err = -EFAULT;
580 break;
581
582 case GET_VLAN_VID_CMD:
583 err = 0;
584 args.u.VID = vlan_dev_vlan_id(dev);
585 if (copy_to_user(arg, &args,
586 sizeof(struct vlan_ioctl_args)))
587 err = -EFAULT;
588 break;
589
590 default:
591 err = -EOPNOTSUPP;
592 break;
593 }
594 out:
595 rtnl_unlock();
596 return err;
597 }
598
vlan_init_net(struct net * net)599 static int __net_init vlan_init_net(struct net *net)
600 {
601 struct vlan_net *vn = net_generic(net, vlan_net_id);
602 int err;
603
604 vn->name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD;
605
606 err = vlan_proc_init(net);
607
608 return err;
609 }
610
vlan_exit_net(struct net * net)611 static void __net_exit vlan_exit_net(struct net *net)
612 {
613 vlan_proc_cleanup(net);
614 }
615
616 static struct pernet_operations vlan_net_ops = {
617 .init = vlan_init_net,
618 .exit = vlan_exit_net,
619 .id = &vlan_net_id,
620 .size = sizeof(struct vlan_net),
621 };
622
vlan_proto_init(void)623 static int __init vlan_proto_init(void)
624 {
625 int err;
626
627 pr_info("%s v%s\n", vlan_fullname, vlan_version);
628
629 err = register_pernet_subsys(&vlan_net_ops);
630 if (err < 0)
631 goto err0;
632
633 err = register_netdevice_notifier(&vlan_notifier_block);
634 if (err < 0)
635 goto err2;
636
637 err = vlan_gvrp_init();
638 if (err < 0)
639 goto err3;
640
641 err = vlan_mvrp_init();
642 if (err < 0)
643 goto err4;
644
645 err = vlan_netlink_init();
646 if (err < 0)
647 goto err5;
648
649 vlan_ioctl_set(vlan_ioctl_handler);
650 return 0;
651
652 err5:
653 vlan_mvrp_uninit();
654 err4:
655 vlan_gvrp_uninit();
656 err3:
657 unregister_netdevice_notifier(&vlan_notifier_block);
658 err2:
659 unregister_pernet_subsys(&vlan_net_ops);
660 err0:
661 return err;
662 }
663
vlan_cleanup_module(void)664 static void __exit vlan_cleanup_module(void)
665 {
666 vlan_ioctl_set(NULL);
667 vlan_netlink_fini();
668
669 unregister_netdevice_notifier(&vlan_notifier_block);
670
671 unregister_pernet_subsys(&vlan_net_ops);
672 rcu_barrier(); /* Wait for completion of call_rcu()'s */
673
674 vlan_mvrp_uninit();
675 vlan_gvrp_uninit();
676 }
677
678 module_init(vlan_proto_init);
679 module_exit(vlan_cleanup_module);
680
681 MODULE_LICENSE("GPL");
682 MODULE_VERSION(DRV_VERSION);
683