969e7004cf86aa7277efd831197d1435c2d7fb68
[deliverable/linux.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 #include <linux/capability.h>
22 #include <linux/module.h>
23 #include <linux/netdevice.h>
24 #include <linux/skbuff.h>
25 #include <linux/slab.h>
26 #include <linux/init.h>
27 #include <linux/rculist.h>
28 #include <net/p8022.h>
29 #include <net/arp.h>
30 #include <linux/rtnetlink.h>
31 #include <linux/notifier.h>
32 #include <net/rtnetlink.h>
33 #include <net/net_namespace.h>
34 #include <net/netns/generic.h>
35 #include <asm/uaccess.h>
36
37 #include <linux/if_vlan.h>
38 #include "vlan.h"
39 #include "vlanproc.h"
40
41 #define DRV_VERSION "1.8"
42
43 /* Global VLAN variables */
44
45 int vlan_net_id __read_mostly;
46
47 const char vlan_fullname[] = "802.1Q VLAN Support";
48 const char vlan_version[] = DRV_VERSION;
49 static const char vlan_copyright[] = "Ben Greear <greearb@candelatech.com>";
50 static const char vlan_buggyright[] = "David S. Miller <davem@redhat.com>";
51
52 /* End of global variables definitions. */
53
54 static void vlan_group_free(struct vlan_group *grp)
55 {
56 int i;
57
58 for (i = 0; i < VLAN_GROUP_ARRAY_SPLIT_PARTS; i++)
59 kfree(grp->vlan_devices_arrays[i]);
60 kfree(grp);
61 }
62
63 static struct vlan_group *vlan_group_alloc(struct net_device *real_dev)
64 {
65 struct vlan_group *grp;
66
67 grp = kzalloc(sizeof(struct vlan_group), GFP_KERNEL);
68 if (!grp)
69 return NULL;
70
71 grp->real_dev = real_dev;
72 return grp;
73 }
74
75 static int vlan_group_prealloc_vid(struct vlan_group *vg, u16 vlan_id)
76 {
77 struct net_device **array;
78 unsigned int size;
79
80 ASSERT_RTNL();
81
82 array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
83 if (array != NULL)
84 return 0;
85
86 size = sizeof(struct net_device *) * VLAN_GROUP_ARRAY_PART_LEN;
87 array = kzalloc(size, GFP_KERNEL);
88 if (array == NULL)
89 return -ENOBUFS;
90
91 vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN] = array;
92 return 0;
93 }
94
95 static void vlan_rcu_free(struct rcu_head *rcu)
96 {
97 vlan_group_free(container_of(rcu, struct vlan_group, rcu));
98 }
99
100 void unregister_vlan_dev(struct net_device *dev, struct list_head *head)
101 {
102 struct vlan_dev_info *vlan = vlan_dev_info(dev);
103 struct net_device *real_dev = vlan->real_dev;
104 const struct net_device_ops *ops = real_dev->netdev_ops;
105 struct vlan_group *grp;
106 u16 vlan_id = vlan->vlan_id;
107
108 ASSERT_RTNL();
109
110 grp = rtnl_dereference(real_dev->vlgrp);
111 BUG_ON(!grp);
112
113 /* Take it out of our own structures, but be sure to interlock with
114 * HW accelerating devices or SW vlan input packet processing if
115 * VLAN is not 0 (leave it there for 802.1p).
116 */
117 if (vlan_id && (real_dev->features & NETIF_F_HW_VLAN_FILTER))
118 ops->ndo_vlan_rx_kill_vid(real_dev, vlan_id);
119
120 grp->nr_vlans--;
121
122 vlan_group_set_device(grp, vlan_id, NULL);
123 if (!grp->killall)
124 synchronize_net();
125
126 unregister_netdevice_queue(dev, head);
127
128 /* If the group is now empty, kill off the group. */
129 if (grp->nr_vlans == 0) {
130 vlan_gvrp_uninit_applicant(real_dev);
131
132 rcu_assign_pointer(real_dev->vlgrp, NULL);
133 if (ops->ndo_vlan_rx_register)
134 ops->ndo_vlan_rx_register(real_dev, NULL);
135
136 /* Free the group, after all cpu's are done. */
137 call_rcu(&grp->rcu, vlan_rcu_free);
138 }
139
140 /* Get rid of the vlan's reference to real_dev */
141 dev_put(real_dev);
142 }
143
144 int vlan_check_real_dev(struct net_device *real_dev, u16 vlan_id)
145 {
146 const char *name = real_dev->name;
147 const struct net_device_ops *ops = real_dev->netdev_ops;
148
149 if (real_dev->features & NETIF_F_VLAN_CHALLENGED) {
150 pr_info("8021q: VLANs not supported on %s\n", name);
151 return -EOPNOTSUPP;
152 }
153
154 if ((real_dev->features & NETIF_F_HW_VLAN_FILTER) &&
155 (!ops->ndo_vlan_rx_add_vid || !ops->ndo_vlan_rx_kill_vid)) {
156 pr_info("8021q: Device %s has buggy VLAN hw accel\n", name);
157 return -EOPNOTSUPP;
158 }
159
160 if (vlan_find_dev(real_dev, vlan_id) != NULL)
161 return -EEXIST;
162
163 return 0;
164 }
165
166 int register_vlan_dev(struct net_device *dev)
167 {
168 struct vlan_dev_info *vlan = vlan_dev_info(dev);
169 struct net_device *real_dev = vlan->real_dev;
170 const struct net_device_ops *ops = real_dev->netdev_ops;
171 u16 vlan_id = vlan->vlan_id;
172 struct vlan_group *grp, *ngrp = NULL;
173 int err;
174
175 grp = rtnl_dereference(real_dev->vlgrp);
176 if (!grp) {
177 ngrp = grp = vlan_group_alloc(real_dev);
178 if (!grp)
179 return -ENOBUFS;
180 err = vlan_gvrp_init_applicant(real_dev);
181 if (err < 0)
182 goto out_free_group;
183 }
184
185 err = vlan_group_prealloc_vid(grp, vlan_id);
186 if (err < 0)
187 goto out_uninit_applicant;
188
189 err = register_netdevice(dev);
190 if (err < 0)
191 goto out_uninit_applicant;
192
193 /* Account for reference in struct vlan_dev_info */
194 dev_hold(real_dev);
195
196 netif_stacked_transfer_operstate(real_dev, dev);
197 linkwatch_fire_event(dev); /* _MUST_ call rfc2863_policy() */
198
199 /* So, got the sucker initialized, now lets place
200 * it into our local structure.
201 */
202 vlan_group_set_device(grp, vlan_id, dev);
203 grp->nr_vlans++;
204
205 if (ngrp) {
206 if (ops->ndo_vlan_rx_register)
207 ops->ndo_vlan_rx_register(real_dev, ngrp);
208 rcu_assign_pointer(real_dev->vlgrp, ngrp);
209 }
210 if (real_dev->features & NETIF_F_HW_VLAN_FILTER)
211 ops->ndo_vlan_rx_add_vid(real_dev, vlan_id);
212
213 return 0;
214
215 out_uninit_applicant:
216 if (ngrp)
217 vlan_gvrp_uninit_applicant(real_dev);
218 out_free_group:
219 if (ngrp) {
220 /* Free the group, after all cpu's are done. */
221 call_rcu(&ngrp->rcu, vlan_rcu_free);
222 }
223 return err;
224 }
225
226 /* Attach a VLAN device to a mac address (ie Ethernet Card).
227 * Returns 0 if the device was created or a negative error code otherwise.
228 */
229 static int register_vlan_device(struct net_device *real_dev, u16 vlan_id)
230 {
231 struct net_device *new_dev;
232 struct net *net = dev_net(real_dev);
233 struct vlan_net *vn = net_generic(net, vlan_net_id);
234 char name[IFNAMSIZ];
235 int err;
236
237 if (vlan_id >= VLAN_VID_MASK)
238 return -ERANGE;
239
240 err = vlan_check_real_dev(real_dev, vlan_id);
241 if (err < 0)
242 return err;
243
244 /* Gotta set up the fields for the device. */
245 switch (vn->name_type) {
246 case VLAN_NAME_TYPE_RAW_PLUS_VID:
247 /* name will look like: eth1.0005 */
248 snprintf(name, IFNAMSIZ, "%s.%.4i", real_dev->name, vlan_id);
249 break;
250 case VLAN_NAME_TYPE_PLUS_VID_NO_PAD:
251 /* Put our vlan.VID in the name.
252 * Name will look like: vlan5
253 */
254 snprintf(name, IFNAMSIZ, "vlan%i", vlan_id);
255 break;
256 case VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD:
257 /* Put our vlan.VID in the name.
258 * Name will look like: eth0.5
259 */
260 snprintf(name, IFNAMSIZ, "%s.%i", real_dev->name, vlan_id);
261 break;
262 case VLAN_NAME_TYPE_PLUS_VID:
263 /* Put our vlan.VID in the name.
264 * Name will look like: vlan0005
265 */
266 default:
267 snprintf(name, IFNAMSIZ, "vlan%.4i", vlan_id);
268 }
269
270 new_dev = alloc_netdev(sizeof(struct vlan_dev_info), name, vlan_setup);
271
272 if (new_dev == NULL)
273 return -ENOBUFS;
274
275 dev_net_set(new_dev, net);
276 /* need 4 bytes for extra VLAN header info,
277 * hope the underlying device can handle it.
278 */
279 new_dev->mtu = real_dev->mtu;
280
281 vlan_dev_info(new_dev)->vlan_id = vlan_id;
282 vlan_dev_info(new_dev)->real_dev = real_dev;
283 vlan_dev_info(new_dev)->dent = NULL;
284 vlan_dev_info(new_dev)->flags = VLAN_FLAG_REORDER_HDR;
285
286 new_dev->rtnl_link_ops = &vlan_link_ops;
287 err = register_vlan_dev(new_dev);
288 if (err < 0)
289 goto out_free_newdev;
290
291 return 0;
292
293 out_free_newdev:
294 free_netdev(new_dev);
295 return err;
296 }
297
298 static void vlan_sync_address(struct net_device *dev,
299 struct net_device *vlandev)
300 {
301 struct vlan_dev_info *vlan = vlan_dev_info(vlandev);
302
303 /* May be called without an actual change */
304 if (!compare_ether_addr(vlan->real_dev_addr, dev->dev_addr))
305 return;
306
307 /* vlan address was different from the old address and is equal to
308 * the new address */
309 if (compare_ether_addr(vlandev->dev_addr, vlan->real_dev_addr) &&
310 !compare_ether_addr(vlandev->dev_addr, dev->dev_addr))
311 dev_uc_del(dev, vlandev->dev_addr);
312
313 /* vlan address was equal to the old address and is different from
314 * the new address */
315 if (!compare_ether_addr(vlandev->dev_addr, vlan->real_dev_addr) &&
316 compare_ether_addr(vlandev->dev_addr, dev->dev_addr))
317 dev_uc_add(dev, vlandev->dev_addr);
318
319 memcpy(vlan->real_dev_addr, dev->dev_addr, ETH_ALEN);
320 }
321
322 static void vlan_transfer_features(struct net_device *dev,
323 struct net_device *vlandev)
324 {
325 vlandev->gso_max_size = dev->gso_max_size;
326
327 if (dev->features & NETIF_F_HW_VLAN_TX)
328 vlandev->hard_header_len = dev->hard_header_len;
329 else
330 vlandev->hard_header_len = dev->hard_header_len + VLAN_HLEN;
331
332 #if defined(CONFIG_FCOE) || defined(CONFIG_FCOE_MODULE)
333 vlandev->fcoe_ddp_xid = dev->fcoe_ddp_xid;
334 #endif
335
336 netdev_update_features(vlandev);
337 }
338
339 static void __vlan_device_event(struct net_device *dev, unsigned long event)
340 {
341 switch (event) {
342 case NETDEV_CHANGENAME:
343 vlan_proc_rem_dev(dev);
344 if (vlan_proc_add_dev(dev) < 0)
345 pr_warning("8021q: failed to change proc name for %s\n",
346 dev->name);
347 break;
348 case NETDEV_REGISTER:
349 if (vlan_proc_add_dev(dev) < 0)
350 pr_warning("8021q: failed to add proc entry for %s\n",
351 dev->name);
352 break;
353 case NETDEV_UNREGISTER:
354 vlan_proc_rem_dev(dev);
355 break;
356 }
357 }
358
359 static int vlan_device_event(struct notifier_block *unused, unsigned long event,
360 void *ptr)
361 {
362 struct net_device *dev = ptr;
363 struct vlan_group *grp;
364 int i, flgs;
365 struct net_device *vlandev;
366 struct vlan_dev_info *vlan;
367 LIST_HEAD(list);
368
369 if (is_vlan_dev(dev))
370 __vlan_device_event(dev, event);
371
372 if ((event == NETDEV_UP) &&
373 (dev->features & NETIF_F_HW_VLAN_FILTER) &&
374 dev->netdev_ops->ndo_vlan_rx_add_vid) {
375 pr_info("8021q: adding VLAN 0 to HW filter on device %s\n",
376 dev->name);
377 dev->netdev_ops->ndo_vlan_rx_add_vid(dev, 0);
378 }
379
380 grp = rtnl_dereference(dev->vlgrp);
381 if (!grp)
382 goto out;
383
384 /* It is OK that we do not hold the group lock right now,
385 * as we run under the RTNL lock.
386 */
387
388 switch (event) {
389 case NETDEV_CHANGE:
390 /* Propagate real device state to vlan devices */
391 for (i = 0; i < VLAN_N_VID; i++) {
392 vlandev = vlan_group_get_device(grp, i);
393 if (!vlandev)
394 continue;
395
396 netif_stacked_transfer_operstate(dev, vlandev);
397 }
398 break;
399
400 case NETDEV_CHANGEADDR:
401 /* Adjust unicast filters on underlying device */
402 for (i = 0; i < VLAN_N_VID; i++) {
403 vlandev = vlan_group_get_device(grp, i);
404 if (!vlandev)
405 continue;
406
407 flgs = vlandev->flags;
408 if (!(flgs & IFF_UP))
409 continue;
410
411 vlan_sync_address(dev, vlandev);
412 }
413 break;
414
415 case NETDEV_CHANGEMTU:
416 for (i = 0; i < VLAN_N_VID; i++) {
417 vlandev = vlan_group_get_device(grp, i);
418 if (!vlandev)
419 continue;
420
421 if (vlandev->mtu <= dev->mtu)
422 continue;
423
424 dev_set_mtu(vlandev, dev->mtu);
425 }
426 break;
427
428 case NETDEV_FEAT_CHANGE:
429 /* Propagate device features to underlying device */
430 for (i = 0; i < VLAN_N_VID; i++) {
431 vlandev = vlan_group_get_device(grp, i);
432 if (!vlandev)
433 continue;
434
435 vlan_transfer_features(dev, vlandev);
436 }
437
438 break;
439
440 case NETDEV_DOWN:
441 /* Put all VLANs for this dev in the down state too. */
442 for (i = 0; i < VLAN_N_VID; i++) {
443 vlandev = vlan_group_get_device(grp, i);
444 if (!vlandev)
445 continue;
446
447 flgs = vlandev->flags;
448 if (!(flgs & IFF_UP))
449 continue;
450
451 vlan = vlan_dev_info(vlandev);
452 if (!(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
453 dev_change_flags(vlandev, flgs & ~IFF_UP);
454 netif_stacked_transfer_operstate(dev, vlandev);
455 }
456 break;
457
458 case NETDEV_UP:
459 /* Put all VLANs for this dev in the up state too. */
460 for (i = 0; i < VLAN_N_VID; i++) {
461 vlandev = vlan_group_get_device(grp, i);
462 if (!vlandev)
463 continue;
464
465 flgs = vlandev->flags;
466 if (flgs & IFF_UP)
467 continue;
468
469 vlan = vlan_dev_info(vlandev);
470 if (!(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
471 dev_change_flags(vlandev, flgs | IFF_UP);
472 netif_stacked_transfer_operstate(dev, vlandev);
473 }
474 break;
475
476 case NETDEV_UNREGISTER:
477 /* twiddle thumbs on netns device moves */
478 if (dev->reg_state != NETREG_UNREGISTERING)
479 break;
480
481 /* Delete all VLANs for this dev. */
482 grp->killall = 1;
483
484 for (i = 0; i < VLAN_N_VID; i++) {
485 vlandev = vlan_group_get_device(grp, i);
486 if (!vlandev)
487 continue;
488
489 /* unregistration of last vlan destroys group, abort
490 * afterwards */
491 if (grp->nr_vlans == 1)
492 i = VLAN_N_VID;
493
494 unregister_vlan_dev(vlandev, &list);
495 }
496 unregister_netdevice_many(&list);
497 break;
498
499 case NETDEV_PRE_TYPE_CHANGE:
500 /* Forbid underlaying device to change its type. */
501 return NOTIFY_BAD;
502
503 case NETDEV_NOTIFY_PEERS:
504 case NETDEV_BONDING_FAILOVER:
505 /* Propagate to vlan devices */
506 for (i = 0; i < VLAN_N_VID; i++) {
507 vlandev = vlan_group_get_device(grp, i);
508 if (!vlandev)
509 continue;
510
511 call_netdevice_notifiers(event, vlandev);
512 }
513 break;
514 }
515
516 out:
517 return NOTIFY_DONE;
518 }
519
520 static struct notifier_block vlan_notifier_block __read_mostly = {
521 .notifier_call = vlan_device_event,
522 };
523
524 /*
525 * VLAN IOCTL handler.
526 * o execute requested action or pass command to the device driver
527 * arg is really a struct vlan_ioctl_args __user *.
528 */
529 static int vlan_ioctl_handler(struct net *net, void __user *arg)
530 {
531 int err;
532 struct vlan_ioctl_args args;
533 struct net_device *dev = NULL;
534
535 if (copy_from_user(&args, arg, sizeof(struct vlan_ioctl_args)))
536 return -EFAULT;
537
538 /* Null terminate this sucker, just in case. */
539 args.device1[23] = 0;
540 args.u.device2[23] = 0;
541
542 rtnl_lock();
543
544 switch (args.cmd) {
545 case SET_VLAN_INGRESS_PRIORITY_CMD:
546 case SET_VLAN_EGRESS_PRIORITY_CMD:
547 case SET_VLAN_FLAG_CMD:
548 case ADD_VLAN_CMD:
549 case DEL_VLAN_CMD:
550 case GET_VLAN_REALDEV_NAME_CMD:
551 case GET_VLAN_VID_CMD:
552 err = -ENODEV;
553 dev = __dev_get_by_name(net, args.device1);
554 if (!dev)
555 goto out;
556
557 err = -EINVAL;
558 if (args.cmd != ADD_VLAN_CMD && !is_vlan_dev(dev))
559 goto out;
560 }
561
562 switch (args.cmd) {
563 case SET_VLAN_INGRESS_PRIORITY_CMD:
564 err = -EPERM;
565 if (!capable(CAP_NET_ADMIN))
566 break;
567 vlan_dev_set_ingress_priority(dev,
568 args.u.skb_priority,
569 args.vlan_qos);
570 err = 0;
571 break;
572
573 case SET_VLAN_EGRESS_PRIORITY_CMD:
574 err = -EPERM;
575 if (!capable(CAP_NET_ADMIN))
576 break;
577 err = vlan_dev_set_egress_priority(dev,
578 args.u.skb_priority,
579 args.vlan_qos);
580 break;
581
582 case SET_VLAN_FLAG_CMD:
583 err = -EPERM;
584 if (!capable(CAP_NET_ADMIN))
585 break;
586 err = vlan_dev_change_flags(dev,
587 args.vlan_qos ? args.u.flag : 0,
588 args.u.flag);
589 break;
590
591 case SET_VLAN_NAME_TYPE_CMD:
592 err = -EPERM;
593 if (!capable(CAP_NET_ADMIN))
594 break;
595 if ((args.u.name_type >= 0) &&
596 (args.u.name_type < VLAN_NAME_TYPE_HIGHEST)) {
597 struct vlan_net *vn;
598
599 vn = net_generic(net, vlan_net_id);
600 vn->name_type = args.u.name_type;
601 err = 0;
602 } else {
603 err = -EINVAL;
604 }
605 break;
606
607 case ADD_VLAN_CMD:
608 err = -EPERM;
609 if (!capable(CAP_NET_ADMIN))
610 break;
611 err = register_vlan_device(dev, args.u.VID);
612 break;
613
614 case DEL_VLAN_CMD:
615 err = -EPERM;
616 if (!capable(CAP_NET_ADMIN))
617 break;
618 unregister_vlan_dev(dev, NULL);
619 err = 0;
620 break;
621
622 case GET_VLAN_REALDEV_NAME_CMD:
623 err = 0;
624 vlan_dev_get_realdev_name(dev, args.u.device2);
625 if (copy_to_user(arg, &args,
626 sizeof(struct vlan_ioctl_args)))
627 err = -EFAULT;
628 break;
629
630 case GET_VLAN_VID_CMD:
631 err = 0;
632 args.u.VID = vlan_dev_vlan_id(dev);
633 if (copy_to_user(arg, &args,
634 sizeof(struct vlan_ioctl_args)))
635 err = -EFAULT;
636 break;
637
638 default:
639 err = -EOPNOTSUPP;
640 break;
641 }
642 out:
643 rtnl_unlock();
644 return err;
645 }
646
647 static int __net_init vlan_init_net(struct net *net)
648 {
649 struct vlan_net *vn = net_generic(net, vlan_net_id);
650 int err;
651
652 vn->name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD;
653
654 err = vlan_proc_init(net);
655
656 return err;
657 }
658
659 static void __net_exit vlan_exit_net(struct net *net)
660 {
661 vlan_proc_cleanup(net);
662 }
663
664 static struct pernet_operations vlan_net_ops = {
665 .init = vlan_init_net,
666 .exit = vlan_exit_net,
667 .id = &vlan_net_id,
668 .size = sizeof(struct vlan_net),
669 };
670
671 static int __init vlan_proto_init(void)
672 {
673 int err;
674
675 pr_info("%s v%s %s\n", vlan_fullname, vlan_version, vlan_copyright);
676 pr_info("All bugs added by %s\n", vlan_buggyright);
677
678 err = register_pernet_subsys(&vlan_net_ops);
679 if (err < 0)
680 goto err0;
681
682 err = register_netdevice_notifier(&vlan_notifier_block);
683 if (err < 0)
684 goto err2;
685
686 err = vlan_gvrp_init();
687 if (err < 0)
688 goto err3;
689
690 err = vlan_netlink_init();
691 if (err < 0)
692 goto err4;
693
694 vlan_ioctl_set(vlan_ioctl_handler);
695 return 0;
696
697 err4:
698 vlan_gvrp_uninit();
699 err3:
700 unregister_netdevice_notifier(&vlan_notifier_block);
701 err2:
702 unregister_pernet_subsys(&vlan_net_ops);
703 err0:
704 return err;
705 }
706
707 static void __exit vlan_cleanup_module(void)
708 {
709 vlan_ioctl_set(NULL);
710 vlan_netlink_fini();
711
712 unregister_netdevice_notifier(&vlan_notifier_block);
713
714 unregister_pernet_subsys(&vlan_net_ops);
715 rcu_barrier(); /* Wait for completion of call_rcu()'s */
716
717 vlan_gvrp_uninit();
718 }
719
720 module_init(vlan_proto_init);
721 module_exit(vlan_cleanup_module);
722
723 MODULE_LICENSE("GPL");
724 MODULE_VERSION(DRV_VERSION);
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