aboutsummaryrefslogblamecommitdiffstats
path: root/net/ipv4/devinet.c
blob: 650dcb12d9a15318ef49c889fffc7a0867b0fb5e (plain) (tree)
1
2
3
4
5
6
7
8
9
10
11
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032










                                                                             
                                         






























































































































































































































                                                                                
                                         



                                       


                                                                      












                                                                      

                                                                  
 






                                                                                       
























                                                                   






                                                                         





























































































































































































































































































































































































































































































































































































































































































































































                                                                                    
                                                                            




                                        
                                                                   



















































                                                                               
                                                                              





















                                                                      
                                                                             







                                                                                







                                                                          
                                


                                                                          





































































































































































































































































                                                                               








                                                                            





























































































































                                                                             
/*
 *	NET3	IP device support routines.
 *
 *	Version: $Id: devinet.c,v 1.44 2001/10/31 21:55:54 davem Exp $
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 *	Derived from the IP parts of dev.c 1.0.19
 * 		Authors:	Ross Biro
 *				Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *				Mark Evans, <evansmp@uhura.aston.ac.uk>
 *
 *	Additional Authors:
 *		Alan Cox, <gw4pts@gw4pts.ampr.org>
 *		Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 *
 *	Changes:
 *		Alexey Kuznetsov:	pa_* fields are replaced with ifaddr
 *					lists.
 *		Cyrus Durgin:		updated for kmod
 *		Matthias Andree:	in devinet_ioctl, compare label and
 *					address (4.4BSD alias style support),
 *					fall back to comparing just the label
 *					if no match found.
 */

#include <linux/config.h>

#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/bitops.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/in.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/if_ether.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/init.h>
#include <linux/notifier.h>
#include <linux/inetdevice.h>
#include <linux/igmp.h>
#ifdef CONFIG_SYSCTL
#include <linux/sysctl.h>
#endif
#include <linux/kmod.h>

#include <net/ip.h>
#include <net/route.h>
#include <net/ip_fib.h>

struct ipv4_devconf ipv4_devconf = {
	.accept_redirects = 1,
	.send_redirects =  1,
	.secure_redirects = 1,
	.shared_media =	  1,
};

static struct ipv4_devconf ipv4_devconf_dflt = {
	.accept_redirects =  1,
	.send_redirects =    1,
	.secure_redirects =  1,
	.shared_media =	     1,
	.accept_source_route = 1,
};

static void rtmsg_ifa(int event, struct in_ifaddr *);

static struct notifier_block *inetaddr_chain;
static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
			 int destroy);
#ifdef CONFIG_SYSCTL
static void devinet_sysctl_register(struct in_device *in_dev,
				    struct ipv4_devconf *p);
static void devinet_sysctl_unregister(struct ipv4_devconf *p);
#endif

/* Locks all the inet devices. */

static struct in_ifaddr *inet_alloc_ifa(void)
{
	struct in_ifaddr *ifa = kmalloc(sizeof(*ifa), GFP_KERNEL);

	if (ifa) {
		memset(ifa, 0, sizeof(*ifa));
		INIT_RCU_HEAD(&ifa->rcu_head);
	}

	return ifa;
}

static void inet_rcu_free_ifa(struct rcu_head *head)
{
	struct in_ifaddr *ifa = container_of(head, struct in_ifaddr, rcu_head);
	if (ifa->ifa_dev)
		in_dev_put(ifa->ifa_dev);
	kfree(ifa);
}

static inline void inet_free_ifa(struct in_ifaddr *ifa)
{
	call_rcu(&ifa->rcu_head, inet_rcu_free_ifa);
}

void in_dev_finish_destroy(struct in_device *idev)
{
	struct net_device *dev = idev->dev;

	BUG_TRAP(!idev->ifa_list);
	BUG_TRAP(!idev->mc_list);
#ifdef NET_REFCNT_DEBUG
	printk(KERN_DEBUG "in_dev_finish_destroy: %p=%s\n",
	       idev, dev ? dev->name : "NIL");
#endif
	dev_put(dev);
	if (!idev->dead)
		printk("Freeing alive in_device %p\n", idev);
	else {
		kfree(idev);
	}
}

struct in_device *inetdev_init(struct net_device *dev)
{
	struct in_device *in_dev;

	ASSERT_RTNL();

	in_dev = kmalloc(sizeof(*in_dev), GFP_KERNEL);
	if (!in_dev)
		goto out;
	memset(in_dev, 0, sizeof(*in_dev));
	INIT_RCU_HEAD(&in_dev->rcu_head);
	memcpy(&in_dev->cnf, &ipv4_devconf_dflt, sizeof(in_dev->cnf));
	in_dev->cnf.sysctl = NULL;
	in_dev->dev = dev;
	if ((in_dev->arp_parms = neigh_parms_alloc(dev, &arp_tbl)) == NULL)
		goto out_kfree;
	/* Reference in_dev->dev */
	dev_hold(dev);
#ifdef CONFIG_SYSCTL
	neigh_sysctl_register(dev, in_dev->arp_parms, NET_IPV4,
			      NET_IPV4_NEIGH, "ipv4", NULL, NULL);
#endif

	/* Account for reference dev->ip_ptr */
	in_dev_hold(in_dev);
	rcu_assign_pointer(dev->ip_ptr, in_dev);

#ifdef CONFIG_SYSCTL
	devinet_sysctl_register(in_dev, &in_dev->cnf);
#endif
	ip_mc_init_dev(in_dev);
	if (dev->flags & IFF_UP)
		ip_mc_up(in_dev);
out:
	return in_dev;
out_kfree:
	kfree(in_dev);
	in_dev = NULL;
	goto out;
}

static void in_dev_rcu_put(struct rcu_head *head)
{
	struct in_device *idev = container_of(head, struct in_device, rcu_head);
	in_dev_put(idev);
}

static void inetdev_destroy(struct in_device *in_dev)
{
	struct in_ifaddr *ifa;
	struct net_device *dev;

	ASSERT_RTNL();

	dev = in_dev->dev;
	if (dev == &loopback_dev)
		return;

	in_dev->dead = 1;

	ip_mc_destroy_dev(in_dev);

	while ((ifa = in_dev->ifa_list) != NULL) {
		inet_del_ifa(in_dev, &in_dev->ifa_list, 0);
		inet_free_ifa(ifa);
	}

#ifdef CONFIG_SYSCTL
	devinet_sysctl_unregister(&in_dev->cnf);
#endif

	dev->ip_ptr = NULL;

#ifdef CONFIG_SYSCTL
	neigh_sysctl_unregister(in_dev->arp_parms);
#endif
	neigh_parms_release(&arp_tbl, in_dev->arp_parms);
	arp_ifdown(dev);

	call_rcu(&in_dev->rcu_head, in_dev_rcu_put);
}

int inet_addr_onlink(struct in_device *in_dev, u32 a, u32 b)
{
	rcu_read_lock();
	for_primary_ifa(in_dev) {
		if (inet_ifa_match(a, ifa)) {
			if (!b || inet_ifa_match(b, ifa)) {
				rcu_read_unlock();
				return 1;
			}
		}
	} endfor_ifa(in_dev);
	rcu_read_unlock();
	return 0;
}

static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
			 int destroy)
{
	struct in_ifaddr *promote = NULL;
	struct in_ifaddr *ifa1 = *ifap;

	ASSERT_RTNL();

	/* 1. Deleting primary ifaddr forces deletion all secondaries 
	 * unless alias promotion is set
	 **/

	if (!(ifa1->ifa_flags & IFA_F_SECONDARY)) {
		struct in_ifaddr *ifa;
		struct in_ifaddr **ifap1 = &ifa1->ifa_next;

		while ((ifa = *ifap1) != NULL) {
			if (!(ifa->ifa_flags & IFA_F_SECONDARY) ||
			    ifa1->ifa_mask != ifa->ifa_mask ||
			    !inet_ifa_match(ifa1->ifa_address, ifa)) {
				ifap1 = &ifa->ifa_next;
				continue;
			}

			if (!IN_DEV_PROMOTE_SECONDARIES(in_dev)) {
				*ifap1 = ifa->ifa_next;

				rtmsg_ifa(RTM_DELADDR, ifa);
				notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa);
				inet_free_ifa(ifa);
			} else {
				promote = ifa;
				break;
			}
		}
	}

	/* 2. Unlink it */

	*ifap = ifa1->ifa_next;

	/* 3. Announce address deletion */

	/* Send message first, then call notifier.
	   At first sight, FIB update triggered by notifier
	   will refer to already deleted ifaddr, that could confuse
	   netlink listeners. It is not true: look, gated sees
	   that route deleted and if it still thinks that ifaddr
	   is valid, it will try to restore deleted routes... Grr.
	   So that, this order is correct.
	 */
	rtmsg_ifa(RTM_DELADDR, ifa1);
	notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1);
	if (destroy) {
		inet_free_ifa(ifa1);

		if (!in_dev->ifa_list)
			inetdev_destroy(in_dev);
	}

	if (promote && IN_DEV_PROMOTE_SECONDARIES(in_dev)) {
		/* not sure if we should send a delete notify first? */
		promote->ifa_flags &= ~IFA_F_SECONDARY;
		rtmsg_ifa(RTM_NEWADDR, promote);
		notifier_call_chain(&inetaddr_chain, NETDEV_UP, promote);
	}
}

static int inet_insert_ifa(struct in_ifaddr *ifa)
{
	struct in_device *in_dev = ifa->ifa_dev;
	struct in_ifaddr *ifa1, **ifap, **last_primary;

	ASSERT_RTNL();

	if (!ifa->ifa_local) {
		inet_free_ifa(ifa);
		return 0;
	}

	ifa->ifa_flags &= ~IFA_F_SECONDARY;
	last_primary = &in_dev->ifa_list;

	for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL;
	     ifap = &ifa1->ifa_next) {
		if (!(ifa1->ifa_flags & IFA_F_SECONDARY) &&
		    ifa->ifa_scope <= ifa1->ifa_scope)
			last_primary = &ifa1->ifa_next;
		if (ifa1->ifa_mask == ifa->ifa_mask &&
		    inet_ifa_match(ifa1->ifa_address, ifa)) {
			if (ifa1->ifa_local == ifa->ifa_local) {
				inet_free_ifa(ifa);
				return -EEXIST;
			}
			if (ifa1->ifa_scope != ifa->ifa_scope) {
				inet_free_ifa(ifa);
				return -EINVAL;
			}
			ifa->ifa_flags |= IFA_F_SECONDARY;
		}
	}

	if (!(ifa->ifa_flags & IFA_F_SECONDARY)) {
		net_srandom(ifa->ifa_local);
		ifap = last_primary;
	}

	ifa->ifa_next = *ifap;
	*ifap = ifa;

	/* Send message first, then call notifier.
	   Notifier will trigger FIB update, so that
	   listeners of netlink will know about new ifaddr */
	rtmsg_ifa(RTM_NEWADDR, ifa);
	notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa);

	return 0;
}

static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa)
{
	struct in_device *in_dev = __in_dev_get(dev);

	ASSERT_RTNL();

	if (!in_dev) {
		in_dev = inetdev_init(dev);
		if (!in_dev) {
			inet_free_ifa(ifa);
			return -ENOBUFS;
		}
	}
	if (ifa->ifa_dev != in_dev) {
		BUG_TRAP(!ifa->ifa_dev);
		in_dev_hold(in_dev);
		ifa->ifa_dev = in_dev;
	}
	if (LOOPBACK(ifa->ifa_local))
		ifa->ifa_scope = RT_SCOPE_HOST;
	return inet_insert_ifa(ifa);
}

struct in_device *inetdev_by_index(int ifindex)
{
	struct net_device *dev;
	struct in_device *in_dev = NULL;
	read_lock(&dev_base_lock);
	dev = __dev_get_by_index(ifindex);
	if (dev)
		in_dev = in_dev_get(dev);
	read_unlock(&dev_base_lock);
	return in_dev;
}

/* Called only from RTNL semaphored context. No locks. */

struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, u32 prefix,
				    u32 mask)
{
	ASSERT_RTNL();

	for_primary_ifa(in_dev) {
		if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa))
			return ifa;
	} endfor_ifa(in_dev);
	return NULL;
}

static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
	struct rtattr **rta = arg;
	struct in_device *in_dev;
	struct ifaddrmsg *ifm = NLMSG_DATA(nlh);
	struct in_ifaddr *ifa, **ifap;

	ASSERT_RTNL();

	if ((in_dev = inetdev_by_index(ifm->ifa_index)) == NULL)
		goto out;
	__in_dev_put(in_dev);

	for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
	     ifap = &ifa->ifa_next) {
		if ((rta[IFA_LOCAL - 1] &&
		     memcmp(RTA_DATA(rta[IFA_LOCAL - 1]),
			    &ifa->ifa_local, 4)) ||
		    (rta[IFA_LABEL - 1] &&
		     rtattr_strcmp(rta[IFA_LABEL - 1], ifa->ifa_label)) ||
		    (rta[IFA_ADDRESS - 1] &&
		     (ifm->ifa_prefixlen != ifa->ifa_prefixlen ||
		      !inet_ifa_match(*(u32*)RTA_DATA(rta[IFA_ADDRESS - 1]),
			      	      ifa))))
			continue;
		inet_del_ifa(in_dev, ifap, 1);
		return 0;
	}
out:
	return -EADDRNOTAVAIL;
}

static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
	struct rtattr **rta = arg;
	struct net_device *dev;
	struct in_device *in_dev;
	struct ifaddrmsg *ifm = NLMSG_DATA(nlh);
	struct in_ifaddr *ifa;
	int rc = -EINVAL;

	ASSERT_RTNL();

	if (ifm->ifa_prefixlen > 32 || !rta[IFA_LOCAL - 1])
		goto out;

	rc = -ENODEV;
	if ((dev = __dev_get_by_index(ifm->ifa_index)) == NULL)
		goto out;

	rc = -ENOBUFS;
	if ((in_dev = __in_dev_get(dev)) == NULL) {
		in_dev = inetdev_init(dev);
		if (!in_dev)
			goto out;
	}

	if ((ifa = inet_alloc_ifa()) == NULL)
		goto out;

	if (!rta[IFA_ADDRESS - 1])
		rta[IFA_ADDRESS - 1] = rta[IFA_LOCAL - 1];
	memcpy(&ifa->ifa_local, RTA_DATA(rta[IFA_LOCAL - 1]), 4);
	memcpy(&ifa->ifa_address, RTA_DATA(rta[IFA_ADDRESS - 1]), 4);
	ifa->ifa_prefixlen = ifm->ifa_prefixlen;
	ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen);
	if (rta[IFA_BROADCAST - 1])
		memcpy(&ifa->ifa_broadcast,
		       RTA_DATA(rta[IFA_BROADCAST - 1]), 4);
	if (rta[IFA_ANYCAST - 1])
		memcpy(&ifa->ifa_anycast, RTA_DATA(rta[IFA_ANYCAST - 1]), 4);
	ifa->ifa_flags = ifm->ifa_flags;
	ifa->ifa_scope = ifm->ifa_scope;
	in_dev_hold(in_dev);
	ifa->ifa_dev   = in_dev;
	if (rta[IFA_LABEL - 1])
		rtattr_strlcpy(ifa->ifa_label, rta[IFA_LABEL - 1], IFNAMSIZ);
	else
		memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);

	rc = inet_insert_ifa(ifa);
out:
	return rc;
}

/*
 *	Determine a default network mask, based on the IP address.
 */

static __inline__ int inet_abc_len(u32 addr)
{
	int rc = -1;	/* Something else, probably a multicast. */

  	if (ZERONET(addr))
  		rc = 0;
	else {
		addr = ntohl(addr);

		if (IN_CLASSA(addr))
			rc = 8;
		else if (IN_CLASSB(addr))
			rc = 16;
		else if (IN_CLASSC(addr))
			rc = 24;
	}

  	return rc;
}


int devinet_ioctl(unsigned int cmd, void __user *arg)
{
	struct ifreq ifr;
	struct sockaddr_in sin_orig;
	struct sockaddr_in *sin = (struct sockaddr_in *)&ifr.ifr_addr;
	struct in_device *in_dev;
	struct in_ifaddr **ifap = NULL;
	struct in_ifaddr *ifa = NULL;
	struct net_device *dev;
	char *colon;
	int ret = -EFAULT;
	int tryaddrmatch = 0;

	/*
	 *	Fetch the caller's info block into kernel space
	 */

	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
		goto out;
	ifr.ifr_name[IFNAMSIZ - 1] = 0;

	/* save original address for comparison */
	memcpy(&sin_orig, sin, sizeof(*sin));

	colon = strchr(ifr.ifr_name, ':');
	if (colon)
		*colon = 0;

#ifdef CONFIG_KMOD
	dev_load(ifr.ifr_name);
#endif

	switch(cmd) {
	case SIOCGIFADDR:	/* Get interface address */
	case SIOCGIFBRDADDR:	/* Get the broadcast address */
	case SIOCGIFDSTADDR:	/* Get the destination address */
	case SIOCGIFNETMASK:	/* Get the netmask for the interface */
		/* Note that these ioctls will not sleep,
		   so that we do not impose a lock.
		   One day we will be forced to put shlock here (I mean SMP)
		 */
		tryaddrmatch = (sin_orig.sin_family == AF_INET);
		memset(sin, 0, sizeof(*sin));
		sin->sin_family = AF_INET;
		break;

	case SIOCSIFFLAGS:
		ret = -EACCES;
		if (!capable(CAP_NET_ADMIN))
			goto out;
		break;
	case SIOCSIFADDR:	/* Set interface address (and family) */
	case SIOCSIFBRDADDR:	/* Set the broadcast address */
	case SIOCSIFDSTADDR:	/* Set the destination address */
	case SIOCSIFNETMASK: 	/* Set the netmask for the interface */
		ret = -EACCES;
		if (!capable(CAP_NET_ADMIN))
			goto out;
		ret = -EINVAL;
		if (sin->sin_family != AF_INET)
			goto out;
		break;
	default:
		ret = -EINVAL;
		goto out;
	}

	rtnl_lock();

	ret = -ENODEV;
	if ((dev = __dev_get_by_name(ifr.ifr_name)) == NULL)
		goto done;

	if (colon)
		*colon = ':';

	if ((in_dev = __in_dev_get(dev)) != NULL) {
		if (tryaddrmatch) {
			/* Matthias Andree */
			/* compare label and address (4.4BSD style) */
			/* note: we only do this for a limited set of ioctls
			   and only if the original address family was AF_INET.
			   This is checked above. */
			for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
			     ifap = &ifa->ifa_next) {
				if (!strcmp(ifr.ifr_name, ifa->ifa_label) &&
				    sin_orig.sin_addr.s_addr ==
							ifa->ifa_address) {
					break; /* found */
				}
			}
		}
		/* we didn't get a match, maybe the application is
		   4.3BSD-style and passed in junk so we fall back to
		   comparing just the label */
		if (!ifa) {
			for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
			     ifap = &ifa->ifa_next)
				if (!strcmp(ifr.ifr_name, ifa->ifa_label))
					break;
		}
	}

	ret = -EADDRNOTAVAIL;
	if (!ifa && cmd != SIOCSIFADDR && cmd != SIOCSIFFLAGS)
		goto done;

	switch(cmd) {
	case SIOCGIFADDR:	/* Get interface address */
		sin->sin_addr.s_addr = ifa->ifa_local;
		goto rarok;

	case SIOCGIFBRDADDR:	/* Get the broadcast address */
		sin->sin_addr.s_addr = ifa->ifa_broadcast;
		goto rarok;

	case SIOCGIFDSTADDR:	/* Get the destination address */
		sin->sin_addr.s_addr = ifa->ifa_address;
		goto rarok;

	case SIOCGIFNETMASK:	/* Get the netmask for the interface */
		sin->sin_addr.s_addr = ifa->ifa_mask;
		goto rarok;

	case SIOCSIFFLAGS:
		if (colon) {
			ret = -EADDRNOTAVAIL;
			if (!ifa)
				break;
			ret = 0;
			if (!(ifr.ifr_flags & IFF_UP))
				inet_del_ifa(in_dev, ifap, 1);
			break;
		}
		ret = dev_change_flags(dev, ifr.ifr_flags);
		break;

	case SIOCSIFADDR:	/* Set interface address (and family) */
		ret = -EINVAL;
		if (inet_abc_len(sin->sin_addr.s_addr) < 0)
			break;

		if (!ifa) {
			ret = -ENOBUFS;
			if ((ifa = inet_alloc_ifa()) == NULL)
				break;
			if (colon)
				memcpy(ifa->ifa_label, ifr.ifr_name, IFNAMSIZ);
			else
				memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
		} else {
			ret = 0;
			if (ifa->ifa_local == sin->sin_addr.s_addr)
				break;
			inet_del_ifa(in_dev, ifap, 0);
			ifa->ifa_broadcast = 0;
			ifa->ifa_anycast = 0;
		}

		ifa->ifa_address = ifa->ifa_local = sin->sin_addr.s_addr;

		if (!(dev->flags & IFF_POINTOPOINT)) {
			ifa->ifa_prefixlen = inet_abc_len(ifa->ifa_address);
			ifa->ifa_mask = inet_make_mask(ifa->ifa_prefixlen);
			if ((dev->flags & IFF_BROADCAST) &&
			    ifa->ifa_prefixlen < 31)
				ifa->ifa_broadcast = ifa->ifa_address |
						     ~ifa->ifa_mask;
		} else {
			ifa->ifa_prefixlen = 32;
			ifa->ifa_mask = inet_make_mask(32);
		}
		ret = inet_set_ifa(dev, ifa);
		break;

	case SIOCSIFBRDADDR:	/* Set the broadcast address */
		ret = 0;
		if (ifa->ifa_broadcast != sin->sin_addr.s_addr) {
			inet_del_ifa(in_dev, ifap, 0);
			ifa->ifa_broadcast = sin->sin_addr.s_addr;
			inet_insert_ifa(ifa);
		}
		break;

	case SIOCSIFDSTADDR:	/* Set the destination address */
		ret = 0;
		if (ifa->ifa_address == sin->sin_addr.s_addr)
			break;
		ret = -EINVAL;
		if (inet_abc_len(sin->sin_addr.s_addr) < 0)
			break;
		ret = 0;
		inet_del_ifa(in_dev, ifap, 0);
		ifa->ifa_address = sin->sin_addr.s_addr;
		inet_insert_ifa(ifa);
		break;

	case SIOCSIFNETMASK: 	/* Set the netmask for the interface */

		/*
		 *	The mask we set must be legal.
		 */
		ret = -EINVAL;
		if (bad_mask(sin->sin_addr.s_addr, 0))
			break;
		ret = 0;
		if (ifa->ifa_mask != sin->sin_addr.s_addr) {
			inet_del_ifa(in_dev, ifap, 0);
			ifa->ifa_mask = sin->sin_addr.s_addr;
			ifa->ifa_prefixlen = inet_mask_len(ifa->ifa_mask);

			/* See if current broadcast address matches
			 * with current netmask, then recalculate
			 * the broadcast address. Otherwise it's a
			 * funny address, so don't touch it since
			 * the user seems to know what (s)he's doing...
			 */
			if ((dev->flags & IFF_BROADCAST) &&
			    (ifa->ifa_prefixlen < 31) &&
			    (ifa->ifa_broadcast ==
			     (ifa->ifa_local|~ifa->ifa_mask))) {
				ifa->ifa_broadcast = (ifa->ifa_local |
						      ~sin->sin_addr.s_addr);
			}
			inet_insert_ifa(ifa);
		}
		break;
	}
done:
	rtnl_unlock();
out:
	return ret;
rarok:
	rtnl_unlock();
	ret = copy_to_user(arg, &ifr, sizeof(struct ifreq)) ? -EFAULT : 0;
	goto out;
}

static int inet_gifconf(struct net_device *dev, char __user *buf, int len)
{
	struct in_device *in_dev = __in_dev_get(dev);
	struct in_ifaddr *ifa;
	struct ifreq ifr;
	int done = 0;

	if (!in_dev || (ifa = in_dev->ifa_list) == NULL)
		goto out;

	for (; ifa; ifa = ifa->ifa_next) {
		if (!buf) {
			done += sizeof(ifr);
			continue;
		}
		if (len < (int) sizeof(ifr))
			break;
		memset(&ifr, 0, sizeof(struct ifreq));
		if (ifa->ifa_label)
			strcpy(ifr.ifr_name, ifa->ifa_label);
		else
			strcpy(ifr.ifr_name, dev->name);

		(*(struct sockaddr_in *)&ifr.ifr_addr).sin_family = AF_INET;
		(*(struct sockaddr_in *)&ifr.ifr_addr).sin_addr.s_addr =
								ifa->ifa_local;

		if (copy_to_user(buf, &ifr, sizeof(struct ifreq))) {
			done = -EFAULT;
			break;
		}
		buf  += sizeof(struct ifreq);
		len  -= sizeof(struct ifreq);
		done += sizeof(struct ifreq);
	}
out:
	return done;
}

u32 inet_select_addr(const struct net_device *dev, u32 dst, int scope)
{
	u32 addr = 0;
	struct in_device *in_dev;

	rcu_read_lock();
	in_dev = __in_dev_get(dev);
	if (!in_dev)
		goto no_in_dev;

	for_primary_ifa(in_dev) {
		if (ifa->ifa_scope > scope)
			continue;
		if (!dst || inet_ifa_match(dst, ifa)) {
			addr = ifa->ifa_local;
			break;
		}
		if (!addr)
			addr = ifa->ifa_local;
	} endfor_ifa(in_dev);
no_in_dev:
	rcu_read_unlock();

	if (addr)
		goto out;

	/* Not loopback addresses on loopback should be preferred
	   in this case. It is importnat that lo is the first interface
	   in dev_base list.
	 */
	read_lock(&dev_base_lock);
	rcu_read_lock();
	for (dev = dev_base; dev; dev = dev->next) {
		if ((in_dev = __in_dev_get(dev)) == NULL)
			continue;

		for_primary_ifa(in_dev) {
			if (ifa->ifa_scope != RT_SCOPE_LINK &&
			    ifa->ifa_scope <= scope) {
				addr = ifa->ifa_local;
				goto out_unlock_both;
			}
		} endfor_ifa(in_dev);
	}
out_unlock_both:
	read_unlock(&dev_base_lock);
	rcu_read_unlock();
out:
	return addr;
}

static u32 confirm_addr_indev(struct in_device *in_dev, u32 dst,
			      u32 local, int scope)
{
	int same = 0;
	u32 addr = 0;

	for_ifa(in_dev) {
		if (!addr &&
		    (local == ifa->ifa_local || !local) &&
		    ifa->ifa_scope <= scope) {
			addr = ifa->ifa_local;
			if (same)
				break;
		}
		if (!same) {
			same = (!local || inet_ifa_match(local, ifa)) &&
				(!dst || inet_ifa_match(dst, ifa));
			if (same && addr) {
				if (local || !dst)
					break;
				/* Is the selected addr into dst subnet? */
				if (inet_ifa_match(addr, ifa))
					break;
				/* No, then can we use new local src? */
				if (ifa->ifa_scope <= scope) {
					addr = ifa->ifa_local;
					break;
				}
				/* search for large dst subnet for addr */
				same = 0;
			}
		}
	} endfor_ifa(in_dev);

	return same? addr : 0;
}

/*
 * Confirm that local IP address exists using wildcards:
 * - dev: only on this interface, 0=any interface
 * - dst: only in the same subnet as dst, 0=any dst
 * - local: address, 0=autoselect the local address
 * - scope: maximum allowed scope value for the local address
 */
u32 inet_confirm_addr(const struct net_device *dev, u32 dst, u32 local, int scope)
{
	u32 addr = 0;
	struct in_device *in_dev;

	if (dev) {
		rcu_read_lock();
		if ((in_dev = __in_dev_get(dev)))
			addr = confirm_addr_indev(in_dev, dst, local, scope);
		rcu_read_unlock();

		return addr;
	}

	read_lock(&dev_base_lock);
	rcu_read_lock();
	for (dev = dev_base; dev; dev = dev->next) {
		if ((in_dev = __in_dev_get(dev))) {
			addr = confirm_addr_indev(in_dev, dst, local, scope);
			if (addr)
				break;
		}
	}
	rcu_read_unlock();
	read_unlock(&dev_base_lock);

	return addr;
}

/*
 *	Device notifier
 */

int register_inetaddr_notifier(struct notifier_block *nb)
{
	return notifier_chain_register(&inetaddr_chain, nb);
}

int unregister_inetaddr_notifier(struct notifier_block *nb)
{
	return notifier_chain_unregister(&inetaddr_chain, nb);
}

/* Rename ifa_labels for a device name change. Make some effort to preserve existing
 * alias numbering and to create unique labels if possible.
*/
static void inetdev_changename(struct net_device *dev, struct in_device *in_dev)
{ 
	struct in_ifaddr *ifa;
	int named = 0;

	for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) { 
		char old[IFNAMSIZ], *dot; 

		memcpy(old, ifa->ifa_label, IFNAMSIZ);
		memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); 
		if (named++ == 0)
			continue;
		dot = strchr(ifa->ifa_label, ':');
		if (dot == NULL) { 
			sprintf(old, ":%d", named); 
			dot = old;
		}
		if (strlen(dot) + strlen(dev->name) < IFNAMSIZ) { 
			strcat(ifa->ifa_label, dot); 
		} else { 
			strcpy(ifa->ifa_label + (IFNAMSIZ - strlen(dot) - 1), dot); 
		} 
	}	
} 

/* Called only under RTNL semaphore */

static int inetdev_event(struct notifier_block *this, unsigned long event,
			 void *ptr)
{
	struct net_device *dev = ptr;
	struct in_device *in_dev = __in_dev_get(dev);

	ASSERT_RTNL();

	if (!in_dev) {
		if (event == NETDEV_REGISTER && dev == &loopback_dev) {
			in_dev = inetdev_init(dev);
			if (!in_dev)
				panic("devinet: Failed to create loopback\n");
			in_dev->cnf.no_xfrm = 1;
			in_dev->cnf.no_policy = 1;
		}
		goto out;
	}

	switch (event) {
	case NETDEV_REGISTER:
		printk(KERN_DEBUG "inetdev_event: bug\n");
		dev->ip_ptr = NULL;
		break;
	case NETDEV_UP:
		if (dev->mtu < 68)
			break;
		if (dev == &loopback_dev) {
			struct in_ifaddr *ifa;
			if ((ifa = inet_alloc_ifa()) != NULL) {
				ifa->ifa_local =
				  ifa->ifa_address = htonl(INADDR_LOOPBACK);
				ifa->ifa_prefixlen = 8;
				ifa->ifa_mask = inet_make_mask(8);
				in_dev_hold(in_dev);
				ifa->ifa_dev = in_dev;
				ifa->ifa_scope = RT_SCOPE_HOST;
				memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
				inet_insert_ifa(ifa);
			}
		}
		ip_mc_up(in_dev);
		break;
	case NETDEV_DOWN:
		ip_mc_down(in_dev);
		break;
	case NETDEV_CHANGEMTU:
		if (dev->mtu >= 68)
			break;
		/* MTU falled under 68, disable IP */
	case NETDEV_UNREGISTER:
		inetdev_destroy(in_dev);
		break;
	case NETDEV_CHANGENAME:
		/* Do not notify about label change, this event is
		 * not interesting to applications using netlink.
		 */
		inetdev_changename(dev, in_dev);

#ifdef CONFIG_SYSCTL
		devinet_sysctl_unregister(&in_dev->cnf);
		neigh_sysctl_unregister(in_dev->arp_parms);
		neigh_sysctl_register(dev, in_dev->arp_parms, NET_IPV4,
				      NET_IPV4_NEIGH, "ipv4", NULL, NULL);
		devinet_sysctl_register(in_dev, &in_dev->cnf);
#endif
		break;
	}
out:
	return NOTIFY_DONE;
}

static struct notifier_block ip_netdev_notifier = {
	.notifier_call =inetdev_event,
};

static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa,
			    u32 pid, u32 seq, int event, unsigned int flags)
{
	struct ifaddrmsg *ifm;
	struct nlmsghdr  *nlh;
	unsigned char	 *b = skb->tail;

	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*ifm), flags);
	ifm = NLMSG_DATA(nlh);
	ifm->ifa_family = AF_INET;
	ifm->ifa_prefixlen = ifa->ifa_prefixlen;
	ifm->ifa_flags = ifa->ifa_flags|IFA_F_PERMANENT;
	ifm->ifa_scope = ifa->ifa_scope;
	ifm->ifa_index = ifa->ifa_dev->dev->ifindex;
	if (ifa->ifa_address)
		RTA_PUT(skb, IFA_ADDRESS, 4, &ifa->ifa_address);
	if (ifa->ifa_local)
		RTA_PUT(skb, IFA_LOCAL, 4, &ifa->ifa_local);
	if (ifa->ifa_broadcast)
		RTA_PUT(skb, IFA_BROADCAST, 4, &ifa->ifa_broadcast);
	if (ifa->ifa_anycast)
		RTA_PUT(skb, IFA_ANYCAST, 4, &ifa->ifa_anycast);
	if (ifa->ifa_label[0])
		RTA_PUT(skb, IFA_LABEL, IFNAMSIZ, &ifa->ifa_label);
	nlh->nlmsg_len = skb->tail - b;
	return skb->len;

nlmsg_failure:
rtattr_failure:
	skb_trim(skb, b - skb->data);
	return -1;
}

static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
{
	int idx, ip_idx;
	struct net_device *dev;
	struct in_device *in_dev;
	struct in_ifaddr *ifa;
	int s_ip_idx, s_idx = cb->args[0];

	s_ip_idx = ip_idx = cb->args[1];
	read_lock(&dev_base_lock);
	for (dev = dev_base, idx = 0; dev; dev = dev->next, idx++) {
		if (idx < s_idx)
			continue;
		if (idx > s_idx)
			s_ip_idx = 0;
		rcu_read_lock();
		if ((in_dev = __in_dev_get(dev)) == NULL) {
			rcu_read_unlock();
			continue;
		}

		for (ifa = in_dev->ifa_list, ip_idx = 0; ifa;
		     ifa = ifa->ifa_next, ip_idx++) {
			if (ip_idx < s_ip_idx)
				continue;
			if (inet_fill_ifaddr(skb, ifa, NETLINK_CB(cb->skb).pid,
					     cb->nlh->nlmsg_seq,
					     RTM_NEWADDR, NLM_F_MULTI) <= 0) {
				rcu_read_unlock();
				goto done;
			}
		}
		rcu_read_unlock();
	}

done:
	read_unlock(&dev_base_lock);
	cb->args[0] = idx;
	cb->args[1] = ip_idx;

	return skb->len;
}

static void rtmsg_ifa(int event, struct in_ifaddr* ifa)
{
	int size = NLMSG_SPACE(sizeof(struct ifaddrmsg) + 128);
	struct sk_buff *skb = alloc_skb(size, GFP_KERNEL);

	if (!skb)
		netlink_set_err(rtnl, 0, RTMGRP_IPV4_IFADDR, ENOBUFS);
	else if (inet_fill_ifaddr(skb, ifa, current->pid, 0, event, 0) < 0) {
		kfree_skb(skb);
		netlink_set_err(rtnl, 0, RTMGRP_IPV4_IFADDR, EINVAL);
	} else {
		NETLINK_CB(skb).dst_groups = RTMGRP_IPV4_IFADDR;
		netlink_broadcast(rtnl, skb, 0, RTMGRP_IPV4_IFADDR, GFP_KERNEL);
	}
}

static struct rtnetlink_link inet_rtnetlink_table[RTM_NR_MSGTYPES] = {
	[RTM_NEWADDR  - RTM_BASE] = { .doit	= inet_rtm_newaddr,	},
	[RTM_DELADDR  - RTM_BASE] = { .doit	= inet_rtm_deladdr,	},
	[RTM_GETADDR  - RTM_BASE] = { .dumpit	= inet_dump_ifaddr,	},
	[RTM_NEWROUTE - RTM_BASE] = { .doit	= inet_rtm_newroute,	},
	[RTM_DELROUTE - RTM_BASE] = { .doit	= inet_rtm_delroute,	},
	[RTM_GETROUTE - RTM_BASE] = { .doit	= inet_rtm_getroute,
				      .dumpit	= inet_dump_fib,	},
#ifdef CONFIG_IP_MULTIPLE_TABLES
	[RTM_NEWRULE  - RTM_BASE] = { .doit	= inet_rtm_newrule,	},
	[RTM_DELRULE  - RTM_BASE] = { .doit	= inet_rtm_delrule,	},
	[RTM_GETRULE  - RTM_BASE] = { .dumpit	= inet_dump_rules,	},
#endif
};

#ifdef CONFIG_SYSCTL

void inet_forward_change(void)
{
	struct net_device *dev;
	int on = ipv4_devconf.forwarding;

	ipv4_devconf.accept_redirects = !on;
	ipv4_devconf_dflt.forwarding = on;

	read_lock(&dev_base_lock);
	for (dev = dev_base; dev; dev = dev->next) {
		struct in_device *in_dev;
		rcu_read_lock();
		in_dev = __in_dev_get(dev);
		if (in_dev)
			in_dev->cnf.forwarding = on;
		rcu_read_unlock();
	}
	read_unlock(&dev_base_lock);

	rt_cache_flush(0);
}

static int devinet_sysctl_forward(ctl_table *ctl, int write,
				  struct file* filp, void __user *buffer,
				  size_t *lenp, loff_t *ppos)
{
	int *valp = ctl->data;
	int val = *valp;
	int ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);

	if (write && *valp != val) {
		if (valp == &ipv4_devconf.forwarding)
			inet_forward_change();
		else if (valp != &ipv4_devconf_dflt.forwarding)
			rt_cache_flush(0);
	}

	return ret;
}

int ipv4_doint_and_flush(ctl_table *ctl, int write,
			 struct file* filp, void __user *buffer,
			 size_t *lenp, loff_t *ppos)
{
	int *valp = ctl->data;
	int val = *valp;
	int ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);

	if (write && *valp != val)
		rt_cache_flush(0);

	return ret;
}

int ipv4_doint_and_flush_strategy(ctl_table *table, int __user *name, int nlen,
				  void __user *oldval, size_t __user *oldlenp,
				  void __user *newval, size_t newlen, 
				  void **context)
{
	int *valp = table->data;
	int new;

	if (!newval || !newlen)
		return 0;

	if (newlen != sizeof(int))
		return -EINVAL;

	if (get_user(new, (int __user *)newval))
		return -EFAULT;

	if (new == *valp)
		return 0;

	if (oldval && oldlenp) {
		size_t len;

		if (get_user(len, oldlenp))
			return -EFAULT;

		if (len) {
			if (len > table->maxlen)
				len = table->maxlen;
			if (copy_to_user(oldval, valp, len))
				return -EFAULT;
			if (put_user(len, oldlenp))
				return -EFAULT;
		}
	}

	*valp = new;
	rt_cache_flush(0);
	return 1;
}


static struct devinet_sysctl_table {
	struct ctl_table_header *sysctl_header;
	ctl_table		devinet_vars[__NET_IPV4_CONF_MAX];
	ctl_table		devinet_dev[2];
	ctl_table		devinet_conf_dir[2];
	ctl_table		devinet_proto_dir[2];
	ctl_table		devinet_root_dir[2];
} devinet_sysctl = {
	.devinet_vars = {
		{
			.ctl_name	= NET_IPV4_CONF_FORWARDING,
			.procname	= "forwarding",
			.data		= &ipv4_devconf.forwarding,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &devinet_sysctl_forward,
		},
		{
			.ctl_name	= NET_IPV4_CONF_MC_FORWARDING,
			.procname	= "mc_forwarding",
			.data		= &ipv4_devconf.mc_forwarding,
			.maxlen		= sizeof(int),
			.mode		= 0444,
			.proc_handler	= &proc_dointvec,
		},
		{
			.ctl_name	= NET_IPV4_CONF_ACCEPT_REDIRECTS,
			.procname	= "accept_redirects",
			.data		= &ipv4_devconf.accept_redirects,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &proc_dointvec,
		},
		{
			.ctl_name	= NET_IPV4_CONF_SECURE_REDIRECTS,
			.procname	= "secure_redirects",
			.data		= &ipv4_devconf.secure_redirects,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &proc_dointvec,
		},
		{
			.ctl_name	= NET_IPV4_CONF_SHARED_MEDIA,
			.procname	= "shared_media",
			.data		= &ipv4_devconf.shared_media,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &proc_dointvec,
		},
		{
			.ctl_name	= NET_IPV4_CONF_RP_FILTER,
			.procname	= "rp_filter",
			.data		= &ipv4_devconf.rp_filter,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &proc_dointvec,
		},
		{
			.ctl_name	= NET_IPV4_CONF_SEND_REDIRECTS,
			.procname	= "send_redirects",
			.data		= &ipv4_devconf.send_redirects,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &proc_dointvec,
		},
		{
			.ctl_name	= NET_IPV4_CONF_ACCEPT_SOURCE_ROUTE,
			.procname	= "accept_source_route",
			.data		= &ipv4_devconf.accept_source_route,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &proc_dointvec,
		},
		{
			.ctl_name	= NET_IPV4_CONF_PROXY_ARP,
			.procname	= "proxy_arp",
			.data		= &ipv4_devconf.proxy_arp,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &proc_dointvec,
		},
		{
			.ctl_name	= NET_IPV4_CONF_MEDIUM_ID,
			.procname	= "medium_id",
			.data		= &ipv4_devconf.medium_id,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &proc_dointvec,
		},
		{
			.ctl_name	= NET_IPV4_CONF_BOOTP_RELAY,
			.procname	= "bootp_relay",
			.data		= &ipv4_devconf.bootp_relay,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &proc_dointvec,
		},
		{
			.ctl_name	= NET_IPV4_CONF_LOG_MARTIANS,
			.procname	= "log_martians",
			.data		= &ipv4_devconf.log_martians,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &proc_dointvec,
		},
		{
			.ctl_name	= NET_IPV4_CONF_TAG,
			.procname	= "tag",
			.data		= &ipv4_devconf.tag,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &proc_dointvec,
		},
		{
			.ctl_name	= NET_IPV4_CONF_ARPFILTER,
			.procname	= "arp_filter",
			.data		= &ipv4_devconf.arp_filter,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &proc_dointvec,
		},
		{
			.ctl_name	= NET_IPV4_CONF_ARP_ANNOUNCE,
			.procname	= "arp_announce",
			.data		= &ipv4_devconf.arp_announce,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &proc_dointvec,
		},
		{
			.ctl_name	= NET_IPV4_CONF_ARP_IGNORE,
			.procname	= "arp_ignore",
			.data		= &ipv4_devconf.arp_ignore,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &proc_dointvec,
		},
		{
			.ctl_name	= NET_IPV4_CONF_NOXFRM,
			.procname	= "disable_xfrm",
			.data		= &ipv4_devconf.no_xfrm,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &ipv4_doint_and_flush,
			.strategy	= &ipv4_doint_and_flush_strategy,
		},
		{
			.ctl_name	= NET_IPV4_CONF_NOPOLICY,
			.procname	= "disable_policy",
			.data		= &ipv4_devconf.no_policy,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &ipv4_doint_and_flush,
			.strategy	= &ipv4_doint_and_flush_strategy,
		},
		{
			.ctl_name	= NET_IPV4_CONF_FORCE_IGMP_VERSION,
			.procname	= "force_igmp_version",
			.data		= &ipv4_devconf.force_igmp_version,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &ipv4_doint_and_flush,
			.strategy	= &ipv4_doint_and_flush_strategy,
		},
		{
			.ctl_name	= NET_IPV4_CONF_PROMOTE_SECONDARIES,
			.procname	= "promote_secondaries",
			.data		= &ipv4_devconf.promote_secondaries,
			.maxlen		= sizeof(int),
			.mode		= 0644,
			.proc_handler	= &ipv4_doint_and_flush,
			.strategy	= &ipv4_doint_and_flush_strategy,
		},
	},
	.devinet_dev = {
		{
			.ctl_name	= NET_PROTO_CONF_ALL,
			.procname	= "all",
			.mode		= 0555,
			.child		= devinet_sysctl.devinet_vars,
		},
	},
	.devinet_conf_dir = {
	        {
			.ctl_name	= NET_IPV4_CONF,
			.procname	= "conf",
			.mode		= 0555,
			.child		= devinet_sysctl.devinet_dev,
		},
	},
	.devinet_proto_dir = {
		{
			.ctl_name	= NET_IPV4,
			.procname	= "ipv4",
			.mode		= 0555,
			.child 		= devinet_sysctl.devinet_conf_dir,
		},
	},
	.devinet_root_dir = {
		{
			.ctl_name	= CTL_NET,
			.procname 	= "net",
			.mode		= 0555,
			.child		= devinet_sysctl.devinet_proto_dir,
		},
	},
};

static void devinet_sysctl_register(struct in_device *in_dev,
				    struct ipv4_devconf *p)
{
	int i;
	struct net_device *dev = in_dev ? in_dev->dev : NULL;
	struct devinet_sysctl_table *t = kmalloc(sizeof(*t), GFP_KERNEL);
	char *dev_name = NULL;

	if (!t)
		return;
	memcpy(t, &devinet_sysctl, sizeof(*t));
	for (i = 0; i < ARRAY_SIZE(t->devinet_vars) - 1; i++) {
		t->devinet_vars[i].data += (char *)p - (char *)&ipv4_devconf;
		t->devinet_vars[i].de = NULL;
	}

	if (dev) {
		dev_name = dev->name; 
		t->devinet_dev[0].ctl_name = dev->ifindex;
	} else {
		dev_name = "default";
		t->devinet_dev[0].ctl_name = NET_PROTO_CONF_DEFAULT;
	}

	/* 
	 * Make a copy of dev_name, because '.procname' is regarded as const 
	 * by sysctl and we wouldn't want anyone to change it under our feet
	 * (see SIOCSIFNAME).
	 */	
	dev_name = net_sysctl_strdup(dev_name);
	if (!dev_name)
	    goto free;

	t->devinet_dev[0].procname    = dev_name;
	t->devinet_dev[0].child	      = t->devinet_vars;
	t->devinet_dev[0].de	      = NULL;
	t->devinet_conf_dir[0].child  = t->devinet_dev;
	t->devinet_conf_dir[0].de     = NULL;
	t->devinet_proto_dir[0].child = t->devinet_conf_dir;
	t->devinet_proto_dir[0].de    = NULL;
	t->devinet_root_dir[0].child  = t->devinet_proto_dir;
	t->devinet_root_dir[0].de     = NULL;

	t->sysctl_header = register_sysctl_table(t->devinet_root_dir, 0);
	if (!t->sysctl_header)
	    goto free_procname;

	p->sysctl = t;
	return;

	/* error path */
 free_procname:
	kfree(dev_name);
 free:
	kfree(t);
	return;
}

static void devinet_sysctl_unregister(struct ipv4_devconf *p)
{
	if (p->sysctl) {
		struct devinet_sysctl_table *t = p->sysctl;
		p->sysctl = NULL;
		unregister_sysctl_table(t->sysctl_header);
		kfree(t->devinet_dev[0].procname);
		kfree(t);
	}
}
#endif

void __init devinet_init(void)
{
	register_gifconf(PF_INET, inet_gifconf);
	register_netdevice_notifier(&ip_netdev_notifier);
	rtnetlink_links[PF_INET] = inet_rtnetlink_table;
#ifdef CONFIG_SYSCTL
	devinet_sysctl.sysctl_header =
		register_sysctl_table(devinet_sysctl.devinet_root_dir, 0);
	devinet_sysctl_register(NULL, &ipv4_devconf_dflt);
#endif
}

EXPORT_SYMBOL(devinet_ioctl);
EXPORT_SYMBOL(in_dev_finish_destroy);
EXPORT_SYMBOL(inet_select_addr);
EXPORT_SYMBOL(inetdev_by_index);
EXPORT_SYMBOL(register_inetaddr_notifier);
EXPORT_SYMBOL(unregister_inetaddr_notifier);