Merge remote-tracking branch 'lsk/v3.10/topic/gator' into linux-linaro-lsk
[firefly-linux-kernel-4.4.55.git] / net / 8021q / vlan.c
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,
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
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
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
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  */
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
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
305 static void vlan_transfer_features(struct net_device *dev,
306                                    struct net_device *vlandev)
307 {
308         struct vlan_dev_priv *vlan = vlan_dev_priv(vlandev);
309
310         vlandev->gso_max_size = dev->gso_max_size;
311
312         if (vlan_hw_offload_capable(dev->features, vlan->vlan_proto))
313                 vlandev->hard_header_len = dev->hard_header_len;
314         else
315                 vlandev->hard_header_len = dev->hard_header_len + VLAN_HLEN;
316
317 #if IS_ENABLED(CONFIG_FCOE)
318         vlandev->fcoe_ddp_xid = dev->fcoe_ddp_xid;
319 #endif
320
321         netdev_update_features(vlandev);
322 }
323
324 static void __vlan_device_event(struct net_device *dev, unsigned long event)
325 {
326         switch (event) {
327         case NETDEV_CHANGENAME:
328                 vlan_proc_rem_dev(dev);
329                 if (vlan_proc_add_dev(dev) < 0)
330                         pr_warn("failed to change proc name for %s\n",
331                                 dev->name);
332                 break;
333         case NETDEV_REGISTER:
334                 if (vlan_proc_add_dev(dev) < 0)
335                         pr_warn("failed to add proc entry for %s\n", dev->name);
336                 break;
337         case NETDEV_UNREGISTER:
338                 vlan_proc_rem_dev(dev);
339                 break;
340         }
341 }
342
343 static int vlan_device_event(struct notifier_block *unused, unsigned long event,
344                              void *ptr)
345 {
346         struct net_device *dev = ptr;
347         struct vlan_group *grp;
348         struct vlan_info *vlan_info;
349         int i, flgs;
350         struct net_device *vlandev;
351         struct vlan_dev_priv *vlan;
352         bool last = false;
353         LIST_HEAD(list);
354
355         if (is_vlan_dev(dev))
356                 __vlan_device_event(dev, event);
357
358         if ((event == NETDEV_UP) &&
359             (dev->features & NETIF_F_HW_VLAN_CTAG_FILTER)) {
360                 pr_info("adding VLAN 0 to HW filter on device %s\n",
361                         dev->name);
362                 vlan_vid_add(dev, htons(ETH_P_8021Q), 0);
363         }
364
365         vlan_info = rtnl_dereference(dev->vlan_info);
366         if (!vlan_info)
367                 goto out;
368         grp = &vlan_info->grp;
369
370         /* It is OK that we do not hold the group lock right now,
371          * as we run under the RTNL lock.
372          */
373
374         switch (event) {
375         case NETDEV_CHANGE:
376                 /* Propagate real device state to vlan devices */
377                 vlan_group_for_each_dev(grp, i, vlandev)
378                         netif_stacked_transfer_operstate(dev, vlandev);
379                 break;
380
381         case NETDEV_CHANGEADDR:
382                 /* Adjust unicast filters on underlying device */
383                 vlan_group_for_each_dev(grp, i, vlandev) {
384                         flgs = vlandev->flags;
385                         if (!(flgs & IFF_UP))
386                                 continue;
387
388                         vlan_sync_address(dev, vlandev);
389                 }
390                 break;
391
392         case NETDEV_CHANGEMTU:
393                 vlan_group_for_each_dev(grp, i, vlandev) {
394                         if (vlandev->mtu <= dev->mtu)
395                                 continue;
396
397                         dev_set_mtu(vlandev, dev->mtu);
398                 }
399                 break;
400
401         case NETDEV_FEAT_CHANGE:
402                 /* Propagate device features to underlying device */
403                 vlan_group_for_each_dev(grp, i, vlandev)
404                         vlan_transfer_features(dev, vlandev);
405                 break;
406
407         case NETDEV_DOWN:
408                 if (dev->features & NETIF_F_HW_VLAN_CTAG_FILTER)
409                         vlan_vid_del(dev, htons(ETH_P_8021Q), 0);
410
411                 /* Put all VLANs for this dev in the down state too.  */
412                 vlan_group_for_each_dev(grp, i, vlandev) {
413                         flgs = vlandev->flags;
414                         if (!(flgs & IFF_UP))
415                                 continue;
416
417                         vlan = vlan_dev_priv(vlandev);
418                         if (!(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
419                                 dev_change_flags(vlandev, flgs & ~IFF_UP);
420                         netif_stacked_transfer_operstate(dev, vlandev);
421                 }
422                 break;
423
424         case NETDEV_UP:
425                 /* Put all VLANs for this dev in the up state too.  */
426                 vlan_group_for_each_dev(grp, i, vlandev) {
427                         flgs = vlandev->flags;
428                         if (flgs & IFF_UP)
429                                 continue;
430
431                         vlan = vlan_dev_priv(vlandev);
432                         if (!(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
433                                 dev_change_flags(vlandev, flgs | IFF_UP);
434                         netif_stacked_transfer_operstate(dev, vlandev);
435                 }
436                 break;
437
438         case NETDEV_UNREGISTER:
439                 /* twiddle thumbs on netns device moves */
440                 if (dev->reg_state != NETREG_UNREGISTERING)
441                         break;
442
443                 vlan_group_for_each_dev(grp, i, vlandev) {
444                         /* removal of last vid destroys vlan_info, abort
445                          * afterwards */
446                         if (vlan_info->nr_vids == 1)
447                                 last = true;
448
449                         unregister_vlan_dev(vlandev, &list);
450                         if (last)
451                                 break;
452                 }
453                 unregister_netdevice_many(&list);
454                 break;
455
456         case NETDEV_PRE_TYPE_CHANGE:
457                 /* Forbid underlaying device to change its type. */
458                 if (vlan_uses_dev(dev))
459                         return NOTIFY_BAD;
460                 break;
461
462         case NETDEV_NOTIFY_PEERS:
463         case NETDEV_BONDING_FAILOVER:
464                 /* Propagate to vlan devices */
465                 vlan_group_for_each_dev(grp, i, vlandev)
466                         call_netdevice_notifiers(event, vlandev);
467                 break;
468         }
469
470 out:
471         return NOTIFY_DONE;
472 }
473
474 static struct notifier_block vlan_notifier_block __read_mostly = {
475         .notifier_call = vlan_device_event,
476 };
477
478 /*
479  *      VLAN IOCTL handler.
480  *      o execute requested action or pass command to the device driver
481  *   arg is really a struct vlan_ioctl_args __user *.
482  */
483 static int vlan_ioctl_handler(struct net *net, void __user *arg)
484 {
485         int err;
486         struct vlan_ioctl_args args;
487         struct net_device *dev = NULL;
488
489         if (copy_from_user(&args, arg, sizeof(struct vlan_ioctl_args)))
490                 return -EFAULT;
491
492         /* Null terminate this sucker, just in case. */
493         args.device1[23] = 0;
494         args.u.device2[23] = 0;
495
496         rtnl_lock();
497
498         switch (args.cmd) {
499         case SET_VLAN_INGRESS_PRIORITY_CMD:
500         case SET_VLAN_EGRESS_PRIORITY_CMD:
501         case SET_VLAN_FLAG_CMD:
502         case ADD_VLAN_CMD:
503         case DEL_VLAN_CMD:
504         case GET_VLAN_REALDEV_NAME_CMD:
505         case GET_VLAN_VID_CMD:
506                 err = -ENODEV;
507                 dev = __dev_get_by_name(net, args.device1);
508                 if (!dev)
509                         goto out;
510
511                 err = -EINVAL;
512                 if (args.cmd != ADD_VLAN_CMD && !is_vlan_dev(dev))
513                         goto out;
514         }
515
516         switch (args.cmd) {
517         case SET_VLAN_INGRESS_PRIORITY_CMD:
518                 err = -EPERM;
519                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
520                         break;
521                 vlan_dev_set_ingress_priority(dev,
522                                               args.u.skb_priority,
523                                               args.vlan_qos);
524                 err = 0;
525                 break;
526
527         case SET_VLAN_EGRESS_PRIORITY_CMD:
528                 err = -EPERM;
529                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
530                         break;
531                 err = vlan_dev_set_egress_priority(dev,
532                                                    args.u.skb_priority,
533                                                    args.vlan_qos);
534                 break;
535
536         case SET_VLAN_FLAG_CMD:
537                 err = -EPERM;
538                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
539                         break;
540                 err = vlan_dev_change_flags(dev,
541                                             args.vlan_qos ? args.u.flag : 0,
542                                             args.u.flag);
543                 break;
544
545         case SET_VLAN_NAME_TYPE_CMD:
546                 err = -EPERM;
547                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
548                         break;
549                 if ((args.u.name_type >= 0) &&
550                     (args.u.name_type < VLAN_NAME_TYPE_HIGHEST)) {
551                         struct vlan_net *vn;
552
553                         vn = net_generic(net, vlan_net_id);
554                         vn->name_type = args.u.name_type;
555                         err = 0;
556                 } else {
557                         err = -EINVAL;
558                 }
559                 break;
560
561         case ADD_VLAN_CMD:
562                 err = -EPERM;
563                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
564                         break;
565                 err = register_vlan_device(dev, args.u.VID);
566                 break;
567
568         case DEL_VLAN_CMD:
569                 err = -EPERM;
570                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
571                         break;
572                 unregister_vlan_dev(dev, NULL);
573                 err = 0;
574                 break;
575
576         case GET_VLAN_REALDEV_NAME_CMD:
577                 err = 0;
578                 vlan_dev_get_realdev_name(dev, args.u.device2);
579                 if (copy_to_user(arg, &args,
580                                  sizeof(struct vlan_ioctl_args)))
581                         err = -EFAULT;
582                 break;
583
584         case GET_VLAN_VID_CMD:
585                 err = 0;
586                 args.u.VID = vlan_dev_vlan_id(dev);
587                 if (copy_to_user(arg, &args,
588                                  sizeof(struct vlan_ioctl_args)))
589                       err = -EFAULT;
590                 break;
591
592         default:
593                 err = -EOPNOTSUPP;
594                 break;
595         }
596 out:
597         rtnl_unlock();
598         return err;
599 }
600
601 static int __net_init vlan_init_net(struct net *net)
602 {
603         struct vlan_net *vn = net_generic(net, vlan_net_id);
604         int err;
605
606         vn->name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD;
607
608         err = vlan_proc_init(net);
609
610         return err;
611 }
612
613 static void __net_exit vlan_exit_net(struct net *net)
614 {
615         vlan_proc_cleanup(net);
616 }
617
618 static struct pernet_operations vlan_net_ops = {
619         .init = vlan_init_net,
620         .exit = vlan_exit_net,
621         .id   = &vlan_net_id,
622         .size = sizeof(struct vlan_net),
623 };
624
625 static int __init vlan_proto_init(void)
626 {
627         int err;
628
629         pr_info("%s v%s\n", vlan_fullname, vlan_version);
630
631         err = register_pernet_subsys(&vlan_net_ops);
632         if (err < 0)
633                 goto err0;
634
635         err = register_netdevice_notifier(&vlan_notifier_block);
636         if (err < 0)
637                 goto err2;
638
639         err = vlan_gvrp_init();
640         if (err < 0)
641                 goto err3;
642
643         err = vlan_mvrp_init();
644         if (err < 0)
645                 goto err4;
646
647         err = vlan_netlink_init();
648         if (err < 0)
649                 goto err5;
650
651         vlan_ioctl_set(vlan_ioctl_handler);
652         return 0;
653
654 err5:
655         vlan_mvrp_uninit();
656 err4:
657         vlan_gvrp_uninit();
658 err3:
659         unregister_netdevice_notifier(&vlan_notifier_block);
660 err2:
661         unregister_pernet_subsys(&vlan_net_ops);
662 err0:
663         return err;
664 }
665
666 static void __exit vlan_cleanup_module(void)
667 {
668         vlan_ioctl_set(NULL);
669         vlan_netlink_fini();
670
671         unregister_netdevice_notifier(&vlan_notifier_block);
672
673         unregister_pernet_subsys(&vlan_net_ops);
674         rcu_barrier(); /* Wait for completion of call_rcu()'s */
675
676         vlan_mvrp_uninit();
677         vlan_gvrp_uninit();
678 }
679
680 module_init(vlan_proto_init);
681 module_exit(vlan_cleanup_module);
682
683 MODULE_LICENSE("GPL");
684 MODULE_VERSION(DRV_VERSION);