[NETNS]: Do not include net/net_namespace.h from seq_file.h
[safe/jmp/linux-2.6] / 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 #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) */
45 static struct hlist_head vlan_group_hash[VLAN_GRP_HASH_SIZE];
46
47 static char vlan_fullname[] = "802.1Q VLAN Support";
48 static char vlan_version[] = DRV_VERSION;
49 static char vlan_copyright[] = "Ben Greear <greearb@candelatech.com>";
50 static char vlan_buggyright[] = "David S. Miller <davem@redhat.com>";
51
52 /* Determines interface naming scheme. */
53 unsigned short vlan_name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD;
54
55 static struct packet_type vlan_packet_type = {
56         .type = __constant_htons(ETH_P_8021Q),
57         .func = vlan_skb_recv, /* VLAN receive method */
58 };
59
60 /* End of global variables definitions. */
61
62 static inline unsigned int vlan_grp_hashfn(unsigned int idx)
63 {
64         return ((idx >> VLAN_GRP_HASH_SHIFT) ^ idx) & VLAN_GRP_HASH_MASK;
65 }
66
67 /* Must be invoked with RCU read lock (no preempt) */
68 static struct vlan_group *__vlan_find_group(int real_dev_ifindex)
69 {
70         struct vlan_group *grp;
71         struct hlist_node *n;
72         int hash = vlan_grp_hashfn(real_dev_ifindex);
73
74         hlist_for_each_entry_rcu(grp, n, &vlan_group_hash[hash], hlist) {
75                 if (grp->real_dev_ifindex == real_dev_ifindex)
76                         return grp;
77         }
78
79         return NULL;
80 }
81
82 /*  Find the protocol handler.  Assumes VID < VLAN_VID_MASK.
83  *
84  * Must be invoked with RCU read lock (no preempt)
85  */
86 struct net_device *__find_vlan_dev(struct net_device *real_dev,
87                                    unsigned short VID)
88 {
89         struct vlan_group *grp = __vlan_find_group(real_dev->ifindex);
90
91         if (grp)
92                 return vlan_group_get_device(grp, VID);
93
94         return NULL;
95 }
96
97 static void vlan_group_free(struct vlan_group *grp)
98 {
99         int i;
100
101         for (i = 0; i < VLAN_GROUP_ARRAY_SPLIT_PARTS; i++)
102                 kfree(grp->vlan_devices_arrays[i]);
103         kfree(grp);
104 }
105
106 static struct vlan_group *vlan_group_alloc(int ifindex)
107 {
108         struct vlan_group *grp;
109
110         grp = kzalloc(sizeof(struct vlan_group), GFP_KERNEL);
111         if (!grp)
112                 return NULL;
113
114         grp->real_dev_ifindex = ifindex;
115         hlist_add_head_rcu(&grp->hlist,
116                            &vlan_group_hash[vlan_grp_hashfn(ifindex)]);
117         return grp;
118 }
119
120 static int vlan_group_prealloc_vid(struct vlan_group *vg, int vid)
121 {
122         struct net_device **array;
123         unsigned int size;
124
125         ASSERT_RTNL();
126
127         array = vg->vlan_devices_arrays[vid / VLAN_GROUP_ARRAY_PART_LEN];
128         if (array != NULL)
129                 return 0;
130
131         size = sizeof(struct net_device *) * VLAN_GROUP_ARRAY_PART_LEN;
132         array = kzalloc(size, GFP_KERNEL);
133         if (array == NULL)
134                 return -ENOBUFS;
135
136         vg->vlan_devices_arrays[vid / VLAN_GROUP_ARRAY_PART_LEN] = array;
137         return 0;
138 }
139
140 static void vlan_rcu_free(struct rcu_head *rcu)
141 {
142         vlan_group_free(container_of(rcu, struct vlan_group, rcu));
143 }
144
145 void unregister_vlan_dev(struct net_device *dev)
146 {
147         struct vlan_dev_info *vlan = vlan_dev_info(dev);
148         struct net_device *real_dev = vlan->real_dev;
149         struct vlan_group *grp;
150         unsigned short vlan_id = vlan->vlan_id;
151
152         ASSERT_RTNL();
153
154         grp = __vlan_find_group(real_dev->ifindex);
155         BUG_ON(!grp);
156
157         vlan_proc_rem_dev(dev);
158
159         /* Take it out of our own structures, but be sure to interlock with
160          * HW accelerating devices or SW vlan input packet processing.
161          */
162         if (real_dev->features & NETIF_F_HW_VLAN_FILTER)
163                 real_dev->vlan_rx_kill_vid(real_dev, vlan_id);
164
165         vlan_group_set_device(grp, vlan_id, NULL);
166         grp->nr_vlans--;
167
168         synchronize_net();
169
170         /* If the group is now empty, kill off the group. */
171         if (grp->nr_vlans == 0) {
172                 if (real_dev->features & NETIF_F_HW_VLAN_RX)
173                         real_dev->vlan_rx_register(real_dev, NULL);
174
175                 hlist_del_rcu(&grp->hlist);
176
177                 /* Free the group, after all cpu's are done. */
178                 call_rcu(&grp->rcu, vlan_rcu_free);
179         }
180
181         /* Get rid of the vlan's reference to real_dev */
182         dev_put(real_dev);
183
184         unregister_netdevice(dev);
185 }
186
187 static void vlan_transfer_operstate(const struct net_device *dev,
188                                     struct net_device *vlandev)
189 {
190         /* Have to respect userspace enforced dormant state
191          * of real device, also must allow supplicant running
192          * on VLAN device
193          */
194         if (dev->operstate == IF_OPER_DORMANT)
195                 netif_dormant_on(vlandev);
196         else
197                 netif_dormant_off(vlandev);
198
199         if (netif_carrier_ok(dev)) {
200                 if (!netif_carrier_ok(vlandev))
201                         netif_carrier_on(vlandev);
202         } else {
203                 if (netif_carrier_ok(vlandev))
204                         netif_carrier_off(vlandev);
205         }
206 }
207
208 int vlan_check_real_dev(struct net_device *real_dev, unsigned short vlan_id)
209 {
210         char *name = real_dev->name;
211
212         if (real_dev->features & NETIF_F_VLAN_CHALLENGED) {
213                 pr_info("8021q: VLANs not supported on %s\n", name);
214                 return -EOPNOTSUPP;
215         }
216
217         if ((real_dev->features & NETIF_F_HW_VLAN_RX) &&
218             !real_dev->vlan_rx_register) {
219                 pr_info("8021q: device %s has buggy VLAN hw accel\n", name);
220                 return -EOPNOTSUPP;
221         }
222
223         if ((real_dev->features & NETIF_F_HW_VLAN_FILTER) &&
224             (!real_dev->vlan_rx_add_vid || !real_dev->vlan_rx_kill_vid)) {
225                 pr_info("8021q: Device %s has buggy VLAN hw accel\n", name);
226                 return -EOPNOTSUPP;
227         }
228
229         /* The real device must be up and operating in order to
230          * assosciate a VLAN device with it.
231          */
232         if (!(real_dev->flags & IFF_UP))
233                 return -ENETDOWN;
234
235         if (__find_vlan_dev(real_dev, vlan_id) != NULL)
236                 return -EEXIST;
237
238         return 0;
239 }
240
241 int register_vlan_dev(struct net_device *dev)
242 {
243         struct vlan_dev_info *vlan = vlan_dev_info(dev);
244         struct net_device *real_dev = vlan->real_dev;
245         unsigned short vlan_id = vlan->vlan_id;
246         struct vlan_group *grp, *ngrp = NULL;
247         int err;
248
249         grp = __vlan_find_group(real_dev->ifindex);
250         if (!grp) {
251                 ngrp = grp = vlan_group_alloc(real_dev->ifindex);
252                 if (!grp)
253                         return -ENOBUFS;
254         }
255
256         err = vlan_group_prealloc_vid(grp, vlan_id);
257         if (err < 0)
258                 goto out_free_group;
259
260         err = register_netdevice(dev);
261         if (err < 0)
262                 goto out_free_group;
263
264         /* Account for reference in struct vlan_dev_info */
265         dev_hold(real_dev);
266
267         vlan_transfer_operstate(real_dev, dev);
268         linkwatch_fire_event(dev); /* _MUST_ call rfc2863_policy() */
269
270         /* So, got the sucker initialized, now lets place
271          * it into our local structure.
272          */
273         vlan_group_set_device(grp, vlan_id, dev);
274         grp->nr_vlans++;
275
276         if (ngrp && real_dev->features & NETIF_F_HW_VLAN_RX)
277                 real_dev->vlan_rx_register(real_dev, ngrp);
278         if (real_dev->features & NETIF_F_HW_VLAN_FILTER)
279                 real_dev->vlan_rx_add_vid(real_dev, vlan_id);
280
281         if (vlan_proc_add_dev(dev) < 0)
282                 pr_warning("8021q: failed to add proc entry for %s\n",
283                            dev->name);
284         return 0;
285
286 out_free_group:
287         if (ngrp)
288                 vlan_group_free(ngrp);
289         return err;
290 }
291
292 /*  Attach a VLAN device to a mac address (ie Ethernet Card).
293  *  Returns 0 if the device was created or a negative error code otherwise.
294  */
295 static int register_vlan_device(struct net_device *real_dev,
296                                 unsigned short VLAN_ID)
297 {
298         struct net_device *new_dev;
299         char name[IFNAMSIZ];
300         int err;
301
302         if (VLAN_ID >= VLAN_VID_MASK)
303                 return -ERANGE;
304
305         err = vlan_check_real_dev(real_dev, VLAN_ID);
306         if (err < 0)
307                 return err;
308
309         /* Gotta set up the fields for the device. */
310         switch (vlan_name_type) {
311         case VLAN_NAME_TYPE_RAW_PLUS_VID:
312                 /* name will look like:  eth1.0005 */
313                 snprintf(name, IFNAMSIZ, "%s.%.4i", real_dev->name, VLAN_ID);
314                 break;
315         case VLAN_NAME_TYPE_PLUS_VID_NO_PAD:
316                 /* Put our vlan.VID in the name.
317                  * Name will look like:  vlan5
318                  */
319                 snprintf(name, IFNAMSIZ, "vlan%i", VLAN_ID);
320                 break;
321         case VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD:
322                 /* Put our vlan.VID in the name.
323                  * Name will look like:  eth0.5
324                  */
325                 snprintf(name, IFNAMSIZ, "%s.%i", real_dev->name, VLAN_ID);
326                 break;
327         case VLAN_NAME_TYPE_PLUS_VID:
328                 /* Put our vlan.VID in the name.
329                  * Name will look like:  vlan0005
330                  */
331         default:
332                 snprintf(name, IFNAMSIZ, "vlan%.4i", VLAN_ID);
333         }
334
335         new_dev = alloc_netdev(sizeof(struct vlan_dev_info), name,
336                                vlan_setup);
337
338         if (new_dev == NULL)
339                 return -ENOBUFS;
340
341         /* need 4 bytes for extra VLAN header info,
342          * hope the underlying device can handle it.
343          */
344         new_dev->mtu = real_dev->mtu;
345
346         vlan_dev_info(new_dev)->vlan_id = VLAN_ID; /* 1 through VLAN_VID_MASK */
347         vlan_dev_info(new_dev)->real_dev = real_dev;
348         vlan_dev_info(new_dev)->dent = NULL;
349         vlan_dev_info(new_dev)->flags = VLAN_FLAG_REORDER_HDR;
350
351         new_dev->rtnl_link_ops = &vlan_link_ops;
352         err = register_vlan_dev(new_dev);
353         if (err < 0)
354                 goto out_free_newdev;
355
356         return 0;
357
358 out_free_newdev:
359         free_netdev(new_dev);
360         return err;
361 }
362
363 static void vlan_sync_address(struct net_device *dev,
364                               struct net_device *vlandev)
365 {
366         struct vlan_dev_info *vlan = vlan_dev_info(vlandev);
367
368         /* May be called without an actual change */
369         if (!compare_ether_addr(vlan->real_dev_addr, dev->dev_addr))
370                 return;
371
372         /* vlan address was different from the old address and is equal to
373          * the new address */
374         if (compare_ether_addr(vlandev->dev_addr, vlan->real_dev_addr) &&
375             !compare_ether_addr(vlandev->dev_addr, dev->dev_addr))
376                 dev_unicast_delete(dev, vlandev->dev_addr, ETH_ALEN);
377
378         /* vlan address was equal to the old address and is different from
379          * the new address */
380         if (!compare_ether_addr(vlandev->dev_addr, vlan->real_dev_addr) &&
381             compare_ether_addr(vlandev->dev_addr, dev->dev_addr))
382                 dev_unicast_add(dev, vlandev->dev_addr, ETH_ALEN);
383
384         memcpy(vlan->real_dev_addr, dev->dev_addr, ETH_ALEN);
385 }
386
387 static int vlan_device_event(struct notifier_block *unused, unsigned long event,
388                              void *ptr)
389 {
390         struct net_device *dev = ptr;
391         struct vlan_group *grp = __vlan_find_group(dev->ifindex);
392         int i, flgs;
393         struct net_device *vlandev;
394
395         if (dev_net(dev) != &init_net)
396                 return NOTIFY_DONE;
397
398         if (!grp)
399                 goto out;
400
401         /* It is OK that we do not hold the group lock right now,
402          * as we run under the RTNL lock.
403          */
404
405         switch (event) {
406         case NETDEV_CHANGE:
407                 /* Propagate real device state to vlan devices */
408                 for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
409                         vlandev = vlan_group_get_device(grp, i);
410                         if (!vlandev)
411                                 continue;
412
413                         vlan_transfer_operstate(dev, vlandev);
414                 }
415                 break;
416
417         case NETDEV_CHANGEADDR:
418                 /* Adjust unicast filters on underlying device */
419                 for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
420                         vlandev = vlan_group_get_device(grp, i);
421                         if (!vlandev)
422                                 continue;
423
424                         flgs = vlandev->flags;
425                         if (!(flgs & IFF_UP))
426                                 continue;
427
428                         vlan_sync_address(dev, vlandev);
429                 }
430                 break;
431
432         case NETDEV_DOWN:
433                 /* Put all VLANs for this dev in the down state too.  */
434                 for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
435                         vlandev = vlan_group_get_device(grp, i);
436                         if (!vlandev)
437                                 continue;
438
439                         flgs = vlandev->flags;
440                         if (!(flgs & IFF_UP))
441                                 continue;
442
443                         dev_change_flags(vlandev, flgs & ~IFF_UP);
444                 }
445                 break;
446
447         case NETDEV_UP:
448                 /* Put all VLANs for this dev in the up state too.  */
449                 for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
450                         vlandev = vlan_group_get_device(grp, i);
451                         if (!vlandev)
452                                 continue;
453
454                         flgs = vlandev->flags;
455                         if (flgs & IFF_UP)
456                                 continue;
457
458                         dev_change_flags(vlandev, flgs | IFF_UP);
459                 }
460                 break;
461
462         case NETDEV_UNREGISTER:
463                 /* Delete all VLANs for this dev. */
464                 for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
465                         vlandev = vlan_group_get_device(grp, i);
466                         if (!vlandev)
467                                 continue;
468
469                         /* unregistration of last vlan destroys group, abort
470                          * afterwards */
471                         if (grp->nr_vlans == 1)
472                                 i = VLAN_GROUP_ARRAY_LEN;
473
474                         unregister_vlan_dev(vlandev);
475                 }
476                 break;
477         }
478
479 out:
480         return NOTIFY_DONE;
481 }
482
483 static struct notifier_block vlan_notifier_block __read_mostly = {
484         .notifier_call = vlan_device_event,
485 };
486
487 /*
488  *      VLAN IOCTL handler.
489  *      o execute requested action or pass command to the device driver
490  *   arg is really a struct vlan_ioctl_args __user *.
491  */
492 static int vlan_ioctl_handler(struct net *net, void __user *arg)
493 {
494         int err;
495         unsigned short vid = 0;
496         struct vlan_ioctl_args args;
497         struct net_device *dev = NULL;
498
499         if (copy_from_user(&args, arg, sizeof(struct vlan_ioctl_args)))
500                 return -EFAULT;
501
502         /* Null terminate this sucker, just in case. */
503         args.device1[23] = 0;
504         args.u.device2[23] = 0;
505
506         rtnl_lock();
507
508         switch (args.cmd) {
509         case SET_VLAN_INGRESS_PRIORITY_CMD:
510         case SET_VLAN_EGRESS_PRIORITY_CMD:
511         case SET_VLAN_FLAG_CMD:
512         case ADD_VLAN_CMD:
513         case DEL_VLAN_CMD:
514         case GET_VLAN_REALDEV_NAME_CMD:
515         case GET_VLAN_VID_CMD:
516                 err = -ENODEV;
517                 dev = __dev_get_by_name(&init_net, args.device1);
518                 if (!dev)
519                         goto out;
520
521                 err = -EINVAL;
522                 if (args.cmd != ADD_VLAN_CMD &&
523                     !(dev->priv_flags & IFF_802_1Q_VLAN))
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_set_vlan_flag(dev,
552                                              args.u.flag,
553                                              args.vlan_qos);
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                         vlan_name_type = args.u.name_type;
563                         err = 0;
564                 } else {
565                         err = -EINVAL;
566                 }
567                 break;
568
569         case ADD_VLAN_CMD:
570                 err = -EPERM;
571                 if (!capable(CAP_NET_ADMIN))
572                         break;
573                 err = register_vlan_device(dev, args.u.VID);
574                 break;
575
576         case DEL_VLAN_CMD:
577                 err = -EPERM;
578                 if (!capable(CAP_NET_ADMIN))
579                         break;
580                 unregister_vlan_dev(dev);
581                 err = 0;
582                 break;
583
584         case GET_VLAN_REALDEV_NAME_CMD:
585                 err = 0;
586                 vlan_dev_get_realdev_name(dev, args.u.device2);
587                 if (copy_to_user(arg, &args,
588                                  sizeof(struct vlan_ioctl_args)))
589                         err = -EFAULT;
590                 break;
591
592         case GET_VLAN_VID_CMD:
593                 err = 0;
594                 vlan_dev_get_vid(dev, &vid);
595                 args.u.VID = vid;
596                 if (copy_to_user(arg, &args,
597                                  sizeof(struct vlan_ioctl_args)))
598                       err = -EFAULT;
599                 break;
600
601         default:
602                 err = -EOPNOTSUPP;
603                 break;
604         }
605 out:
606         rtnl_unlock();
607         return err;
608 }
609
610 static int __init vlan_proto_init(void)
611 {
612         int err;
613
614         pr_info("%s v%s %s\n", vlan_fullname, vlan_version, vlan_copyright);
615         pr_info("All bugs added by %s\n", vlan_buggyright);
616
617         err = vlan_proc_init();
618         if (err < 0)
619                 goto err1;
620
621         err = register_netdevice_notifier(&vlan_notifier_block);
622         if (err < 0)
623                 goto err2;
624
625         err = vlan_netlink_init();
626         if (err < 0)
627                 goto err3;
628
629         dev_add_pack(&vlan_packet_type);
630         vlan_ioctl_set(vlan_ioctl_handler);
631         return 0;
632
633 err3:
634         unregister_netdevice_notifier(&vlan_notifier_block);
635 err2:
636         vlan_proc_cleanup();
637 err1:
638         return err;
639 }
640
641 static void __exit vlan_cleanup_module(void)
642 {
643         unsigned int i;
644
645         vlan_ioctl_set(NULL);
646         vlan_netlink_fini();
647
648         unregister_netdevice_notifier(&vlan_notifier_block);
649
650         dev_remove_pack(&vlan_packet_type);
651
652         /* This table must be empty if there are no module references left. */
653         for (i = 0; i < VLAN_GRP_HASH_SIZE; i++)
654                 BUG_ON(!hlist_empty(&vlan_group_hash[i]));
655
656         vlan_proc_cleanup();
657
658         synchronize_net();
659 }
660
661 module_init(vlan_proto_init);
662 module_exit(vlan_cleanup_module);
663
664 MODULE_LICENSE("GPL");
665 MODULE_VERSION(DRV_VERSION);