xref: /linux/net/ipv4/devinet.c (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
1 /*
2  *	NET3	IP device support routines.
3  *
4  *		This program is free software; you can redistribute it and/or
5  *		modify it under the terms of the GNU General Public License
6  *		as published by the Free Software Foundation; either version
7  *		2 of the License, or (at your option) any later version.
8  *
9  *	Derived from the IP parts of dev.c 1.0.19
10  * 		Authors:	Ross Biro
11  *				Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12  *				Mark Evans, <evansmp@uhura.aston.ac.uk>
13  *
14  *	Additional Authors:
15  *		Alan Cox, <gw4pts@gw4pts.ampr.org>
16  *		Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
17  *
18  *	Changes:
19  *		Alexey Kuznetsov:	pa_* fields are replaced with ifaddr
20  *					lists.
21  *		Cyrus Durgin:		updated for kmod
22  *		Matthias Andree:	in devinet_ioctl, compare label and
23  *					address (4.4BSD alias style support),
24  *					fall back to comparing just the label
25  *					if no match found.
26  */
27 
28 
29 #include <asm/uaccess.h>
30 #include <linux/bitops.h>
31 #include <linux/capability.h>
32 #include <linux/module.h>
33 #include <linux/types.h>
34 #include <linux/kernel.h>
35 #include <linux/string.h>
36 #include <linux/mm.h>
37 #include <linux/socket.h>
38 #include <linux/sockios.h>
39 #include <linux/in.h>
40 #include <linux/errno.h>
41 #include <linux/interrupt.h>
42 #include <linux/if_addr.h>
43 #include <linux/if_ether.h>
44 #include <linux/inet.h>
45 #include <linux/netdevice.h>
46 #include <linux/etherdevice.h>
47 #include <linux/skbuff.h>
48 #include <linux/init.h>
49 #include <linux/notifier.h>
50 #include <linux/inetdevice.h>
51 #include <linux/igmp.h>
52 #include <linux/slab.h>
53 #include <linux/hash.h>
54 #ifdef CONFIG_SYSCTL
55 #include <linux/sysctl.h>
56 #endif
57 #include <linux/kmod.h>
58 #include <linux/netconf.h>
59 
60 #include <net/arp.h>
61 #include <net/ip.h>
62 #include <net/route.h>
63 #include <net/ip_fib.h>
64 #include <net/rtnetlink.h>
65 #include <net/net_namespace.h>
66 #include <net/addrconf.h>
67 
68 #include "fib_lookup.h"
69 
70 static struct ipv4_devconf ipv4_devconf = {
71 	.data = {
72 		[IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1,
73 		[IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1,
74 		[IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1,
75 		[IPV4_DEVCONF_SHARED_MEDIA - 1] = 1,
76 		[IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL - 1] = 10000 /*ms*/,
77 		[IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL - 1] =  1000 /*ms*/,
78 	},
79 };
80 
81 static struct ipv4_devconf ipv4_devconf_dflt = {
82 	.data = {
83 		[IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1,
84 		[IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1,
85 		[IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1,
86 		[IPV4_DEVCONF_SHARED_MEDIA - 1] = 1,
87 		[IPV4_DEVCONF_ACCEPT_SOURCE_ROUTE - 1] = 1,
88 		[IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL - 1] = 10000 /*ms*/,
89 		[IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL - 1] =  1000 /*ms*/,
90 	},
91 };
92 
93 #define IPV4_DEVCONF_DFLT(net, attr) \
94 	IPV4_DEVCONF((*net->ipv4.devconf_dflt), attr)
95 
96 static const struct nla_policy ifa_ipv4_policy[IFA_MAX+1] = {
97 	[IFA_LOCAL]     	= { .type = NLA_U32 },
98 	[IFA_ADDRESS]   	= { .type = NLA_U32 },
99 	[IFA_BROADCAST] 	= { .type = NLA_U32 },
100 	[IFA_LABEL]     	= { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
101 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
102 	[IFA_FLAGS]		= { .type = NLA_U32 },
103 };
104 
105 #define IN4_ADDR_HSIZE_SHIFT	8
106 #define IN4_ADDR_HSIZE		(1U << IN4_ADDR_HSIZE_SHIFT)
107 
108 static struct hlist_head inet_addr_lst[IN4_ADDR_HSIZE];
109 
110 static u32 inet_addr_hash(const struct net *net, __be32 addr)
111 {
112 	u32 val = (__force u32) addr ^ net_hash_mix(net);
113 
114 	return hash_32(val, IN4_ADDR_HSIZE_SHIFT);
115 }
116 
117 static void inet_hash_insert(struct net *net, struct in_ifaddr *ifa)
118 {
119 	u32 hash = inet_addr_hash(net, ifa->ifa_local);
120 
121 	ASSERT_RTNL();
122 	hlist_add_head_rcu(&ifa->hash, &inet_addr_lst[hash]);
123 }
124 
125 static void inet_hash_remove(struct in_ifaddr *ifa)
126 {
127 	ASSERT_RTNL();
128 	hlist_del_init_rcu(&ifa->hash);
129 }
130 
131 /**
132  * __ip_dev_find - find the first device with a given source address.
133  * @net: the net namespace
134  * @addr: the source address
135  * @devref: if true, take a reference on the found device
136  *
137  * If a caller uses devref=false, it should be protected by RCU, or RTNL
138  */
139 struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref)
140 {
141 	u32 hash = inet_addr_hash(net, addr);
142 	struct net_device *result = NULL;
143 	struct in_ifaddr *ifa;
144 
145 	rcu_read_lock();
146 	hlist_for_each_entry_rcu(ifa, &inet_addr_lst[hash], hash) {
147 		if (ifa->ifa_local == addr) {
148 			struct net_device *dev = ifa->ifa_dev->dev;
149 
150 			if (!net_eq(dev_net(dev), net))
151 				continue;
152 			result = dev;
153 			break;
154 		}
155 	}
156 	if (!result) {
157 		struct flowi4 fl4 = { .daddr = addr };
158 		struct fib_result res = { 0 };
159 		struct fib_table *local;
160 
161 		/* Fallback to FIB local table so that communication
162 		 * over loopback subnets work.
163 		 */
164 		local = fib_get_table(net, RT_TABLE_LOCAL);
165 		if (local &&
166 		    !fib_table_lookup(local, &fl4, &res, FIB_LOOKUP_NOREF) &&
167 		    res.type == RTN_LOCAL)
168 			result = FIB_RES_DEV(res);
169 	}
170 	if (result && devref)
171 		dev_hold(result);
172 	rcu_read_unlock();
173 	return result;
174 }
175 EXPORT_SYMBOL(__ip_dev_find);
176 
177 static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32);
178 
179 static BLOCKING_NOTIFIER_HEAD(inetaddr_chain);
180 static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
181 			 int destroy);
182 #ifdef CONFIG_SYSCTL
183 static int devinet_sysctl_register(struct in_device *idev);
184 static void devinet_sysctl_unregister(struct in_device *idev);
185 #else
186 static int devinet_sysctl_register(struct in_device *idev)
187 {
188 	return 0;
189 }
190 static void devinet_sysctl_unregister(struct in_device *idev)
191 {
192 }
193 #endif
194 
195 /* Locks all the inet devices. */
196 
197 static struct in_ifaddr *inet_alloc_ifa(void)
198 {
199 	return kzalloc(sizeof(struct in_ifaddr), GFP_KERNEL);
200 }
201 
202 static void inet_rcu_free_ifa(struct rcu_head *head)
203 {
204 	struct in_ifaddr *ifa = container_of(head, struct in_ifaddr, rcu_head);
205 	if (ifa->ifa_dev)
206 		in_dev_put(ifa->ifa_dev);
207 	kfree(ifa);
208 }
209 
210 static void inet_free_ifa(struct in_ifaddr *ifa)
211 {
212 	call_rcu(&ifa->rcu_head, inet_rcu_free_ifa);
213 }
214 
215 void in_dev_finish_destroy(struct in_device *idev)
216 {
217 	struct net_device *dev = idev->dev;
218 
219 	WARN_ON(idev->ifa_list);
220 	WARN_ON(idev->mc_list);
221 	kfree(rcu_dereference_protected(idev->mc_hash, 1));
222 #ifdef NET_REFCNT_DEBUG
223 	pr_debug("%s: %p=%s\n", __func__, idev, dev ? dev->name : "NIL");
224 #endif
225 	dev_put(dev);
226 	if (!idev->dead)
227 		pr_err("Freeing alive in_device %p\n", idev);
228 	else
229 		kfree(idev);
230 }
231 EXPORT_SYMBOL(in_dev_finish_destroy);
232 
233 static struct in_device *inetdev_init(struct net_device *dev)
234 {
235 	struct in_device *in_dev;
236 	int err = -ENOMEM;
237 
238 	ASSERT_RTNL();
239 
240 	in_dev = kzalloc(sizeof(*in_dev), GFP_KERNEL);
241 	if (!in_dev)
242 		goto out;
243 	memcpy(&in_dev->cnf, dev_net(dev)->ipv4.devconf_dflt,
244 			sizeof(in_dev->cnf));
245 	in_dev->cnf.sysctl = NULL;
246 	in_dev->dev = dev;
247 	in_dev->arp_parms = neigh_parms_alloc(dev, &arp_tbl);
248 	if (!in_dev->arp_parms)
249 		goto out_kfree;
250 	if (IPV4_DEVCONF(in_dev->cnf, FORWARDING))
251 		dev_disable_lro(dev);
252 	/* Reference in_dev->dev */
253 	dev_hold(dev);
254 	/* Account for reference dev->ip_ptr (below) */
255 	in_dev_hold(in_dev);
256 
257 	err = devinet_sysctl_register(in_dev);
258 	if (err) {
259 		in_dev->dead = 1;
260 		in_dev_put(in_dev);
261 		in_dev = NULL;
262 		goto out;
263 	}
264 	ip_mc_init_dev(in_dev);
265 	if (dev->flags & IFF_UP)
266 		ip_mc_up(in_dev);
267 
268 	/* we can receive as soon as ip_ptr is set -- do this last */
269 	rcu_assign_pointer(dev->ip_ptr, in_dev);
270 out:
271 	return in_dev ?: ERR_PTR(err);
272 out_kfree:
273 	kfree(in_dev);
274 	in_dev = NULL;
275 	goto out;
276 }
277 
278 static void in_dev_rcu_put(struct rcu_head *head)
279 {
280 	struct in_device *idev = container_of(head, struct in_device, rcu_head);
281 	in_dev_put(idev);
282 }
283 
284 static void inetdev_destroy(struct in_device *in_dev)
285 {
286 	struct in_ifaddr *ifa;
287 	struct net_device *dev;
288 
289 	ASSERT_RTNL();
290 
291 	dev = in_dev->dev;
292 
293 	in_dev->dead = 1;
294 
295 	ip_mc_destroy_dev(in_dev);
296 
297 	while ((ifa = in_dev->ifa_list) != NULL) {
298 		inet_del_ifa(in_dev, &in_dev->ifa_list, 0);
299 		inet_free_ifa(ifa);
300 	}
301 
302 	RCU_INIT_POINTER(dev->ip_ptr, NULL);
303 
304 	devinet_sysctl_unregister(in_dev);
305 	neigh_parms_release(&arp_tbl, in_dev->arp_parms);
306 	arp_ifdown(dev);
307 
308 	call_rcu(&in_dev->rcu_head, in_dev_rcu_put);
309 }
310 
311 int inet_addr_onlink(struct in_device *in_dev, __be32 a, __be32 b)
312 {
313 	rcu_read_lock();
314 	for_primary_ifa(in_dev) {
315 		if (inet_ifa_match(a, ifa)) {
316 			if (!b || inet_ifa_match(b, ifa)) {
317 				rcu_read_unlock();
318 				return 1;
319 			}
320 		}
321 	} endfor_ifa(in_dev);
322 	rcu_read_unlock();
323 	return 0;
324 }
325 
326 static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
327 			 int destroy, struct nlmsghdr *nlh, u32 portid)
328 {
329 	struct in_ifaddr *promote = NULL;
330 	struct in_ifaddr *ifa, *ifa1 = *ifap;
331 	struct in_ifaddr *last_prim = in_dev->ifa_list;
332 	struct in_ifaddr *prev_prom = NULL;
333 	int do_promote = IN_DEV_PROMOTE_SECONDARIES(in_dev);
334 
335 	ASSERT_RTNL();
336 
337 	/* 1. Deleting primary ifaddr forces deletion all secondaries
338 	 * unless alias promotion is set
339 	 **/
340 
341 	if (!(ifa1->ifa_flags & IFA_F_SECONDARY)) {
342 		struct in_ifaddr **ifap1 = &ifa1->ifa_next;
343 
344 		while ((ifa = *ifap1) != NULL) {
345 			if (!(ifa->ifa_flags & IFA_F_SECONDARY) &&
346 			    ifa1->ifa_scope <= ifa->ifa_scope)
347 				last_prim = ifa;
348 
349 			if (!(ifa->ifa_flags & IFA_F_SECONDARY) ||
350 			    ifa1->ifa_mask != ifa->ifa_mask ||
351 			    !inet_ifa_match(ifa1->ifa_address, ifa)) {
352 				ifap1 = &ifa->ifa_next;
353 				prev_prom = ifa;
354 				continue;
355 			}
356 
357 			if (!do_promote) {
358 				inet_hash_remove(ifa);
359 				*ifap1 = ifa->ifa_next;
360 
361 				rtmsg_ifa(RTM_DELADDR, ifa, nlh, portid);
362 				blocking_notifier_call_chain(&inetaddr_chain,
363 						NETDEV_DOWN, ifa);
364 				inet_free_ifa(ifa);
365 			} else {
366 				promote = ifa;
367 				break;
368 			}
369 		}
370 	}
371 
372 	/* On promotion all secondaries from subnet are changing
373 	 * the primary IP, we must remove all their routes silently
374 	 * and later to add them back with new prefsrc. Do this
375 	 * while all addresses are on the device list.
376 	 */
377 	for (ifa = promote; ifa; ifa = ifa->ifa_next) {
378 		if (ifa1->ifa_mask == ifa->ifa_mask &&
379 		    inet_ifa_match(ifa1->ifa_address, ifa))
380 			fib_del_ifaddr(ifa, ifa1);
381 	}
382 
383 	/* 2. Unlink it */
384 
385 	*ifap = ifa1->ifa_next;
386 	inet_hash_remove(ifa1);
387 
388 	/* 3. Announce address deletion */
389 
390 	/* Send message first, then call notifier.
391 	   At first sight, FIB update triggered by notifier
392 	   will refer to already deleted ifaddr, that could confuse
393 	   netlink listeners. It is not true: look, gated sees
394 	   that route deleted and if it still thinks that ifaddr
395 	   is valid, it will try to restore deleted routes... Grr.
396 	   So that, this order is correct.
397 	 */
398 	rtmsg_ifa(RTM_DELADDR, ifa1, nlh, portid);
399 	blocking_notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1);
400 
401 	if (promote) {
402 		struct in_ifaddr *next_sec = promote->ifa_next;
403 
404 		if (prev_prom) {
405 			prev_prom->ifa_next = promote->ifa_next;
406 			promote->ifa_next = last_prim->ifa_next;
407 			last_prim->ifa_next = promote;
408 		}
409 
410 		promote->ifa_flags &= ~IFA_F_SECONDARY;
411 		rtmsg_ifa(RTM_NEWADDR, promote, nlh, portid);
412 		blocking_notifier_call_chain(&inetaddr_chain,
413 				NETDEV_UP, promote);
414 		for (ifa = next_sec; ifa; ifa = ifa->ifa_next) {
415 			if (ifa1->ifa_mask != ifa->ifa_mask ||
416 			    !inet_ifa_match(ifa1->ifa_address, ifa))
417 					continue;
418 			fib_add_ifaddr(ifa);
419 		}
420 
421 	}
422 	if (destroy)
423 		inet_free_ifa(ifa1);
424 }
425 
426 static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
427 			 int destroy)
428 {
429 	__inet_del_ifa(in_dev, ifap, destroy, NULL, 0);
430 }
431 
432 static void check_lifetime(struct work_struct *work);
433 
434 static DECLARE_DELAYED_WORK(check_lifetime_work, check_lifetime);
435 
436 static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh,
437 			     u32 portid)
438 {
439 	struct in_device *in_dev = ifa->ifa_dev;
440 	struct in_ifaddr *ifa1, **ifap, **last_primary;
441 
442 	ASSERT_RTNL();
443 
444 	if (!ifa->ifa_local) {
445 		inet_free_ifa(ifa);
446 		return 0;
447 	}
448 
449 	ifa->ifa_flags &= ~IFA_F_SECONDARY;
450 	last_primary = &in_dev->ifa_list;
451 
452 	for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL;
453 	     ifap = &ifa1->ifa_next) {
454 		if (!(ifa1->ifa_flags & IFA_F_SECONDARY) &&
455 		    ifa->ifa_scope <= ifa1->ifa_scope)
456 			last_primary = &ifa1->ifa_next;
457 		if (ifa1->ifa_mask == ifa->ifa_mask &&
458 		    inet_ifa_match(ifa1->ifa_address, ifa)) {
459 			if (ifa1->ifa_local == ifa->ifa_local) {
460 				inet_free_ifa(ifa);
461 				return -EEXIST;
462 			}
463 			if (ifa1->ifa_scope != ifa->ifa_scope) {
464 				inet_free_ifa(ifa);
465 				return -EINVAL;
466 			}
467 			ifa->ifa_flags |= IFA_F_SECONDARY;
468 		}
469 	}
470 
471 	if (!(ifa->ifa_flags & IFA_F_SECONDARY)) {
472 		prandom_seed((__force u32) ifa->ifa_local);
473 		ifap = last_primary;
474 	}
475 
476 	ifa->ifa_next = *ifap;
477 	*ifap = ifa;
478 
479 	inet_hash_insert(dev_net(in_dev->dev), ifa);
480 
481 	cancel_delayed_work(&check_lifetime_work);
482 	queue_delayed_work(system_power_efficient_wq, &check_lifetime_work, 0);
483 
484 	/* Send message first, then call notifier.
485 	   Notifier will trigger FIB update, so that
486 	   listeners of netlink will know about new ifaddr */
487 	rtmsg_ifa(RTM_NEWADDR, ifa, nlh, portid);
488 	blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa);
489 
490 	return 0;
491 }
492 
493 static int inet_insert_ifa(struct in_ifaddr *ifa)
494 {
495 	return __inet_insert_ifa(ifa, NULL, 0);
496 }
497 
498 static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa)
499 {
500 	struct in_device *in_dev = __in_dev_get_rtnl(dev);
501 
502 	ASSERT_RTNL();
503 
504 	if (!in_dev) {
505 		inet_free_ifa(ifa);
506 		return -ENOBUFS;
507 	}
508 	ipv4_devconf_setall(in_dev);
509 	neigh_parms_data_state_setall(in_dev->arp_parms);
510 	if (ifa->ifa_dev != in_dev) {
511 		WARN_ON(ifa->ifa_dev);
512 		in_dev_hold(in_dev);
513 		ifa->ifa_dev = in_dev;
514 	}
515 	if (ipv4_is_loopback(ifa->ifa_local))
516 		ifa->ifa_scope = RT_SCOPE_HOST;
517 	return inet_insert_ifa(ifa);
518 }
519 
520 /* Caller must hold RCU or RTNL :
521  * We dont take a reference on found in_device
522  */
523 struct in_device *inetdev_by_index(struct net *net, int ifindex)
524 {
525 	struct net_device *dev;
526 	struct in_device *in_dev = NULL;
527 
528 	rcu_read_lock();
529 	dev = dev_get_by_index_rcu(net, ifindex);
530 	if (dev)
531 		in_dev = rcu_dereference_rtnl(dev->ip_ptr);
532 	rcu_read_unlock();
533 	return in_dev;
534 }
535 EXPORT_SYMBOL(inetdev_by_index);
536 
537 /* Called only from RTNL semaphored context. No locks. */
538 
539 struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix,
540 				    __be32 mask)
541 {
542 	ASSERT_RTNL();
543 
544 	for_primary_ifa(in_dev) {
545 		if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa))
546 			return ifa;
547 	} endfor_ifa(in_dev);
548 	return NULL;
549 }
550 
551 static int ip_mc_config(struct sock *sk, bool join, const struct in_ifaddr *ifa)
552 {
553 	struct ip_mreqn mreq = {
554 		.imr_multiaddr.s_addr = ifa->ifa_address,
555 		.imr_ifindex = ifa->ifa_dev->dev->ifindex,
556 	};
557 	int ret;
558 
559 	ASSERT_RTNL();
560 
561 	lock_sock(sk);
562 	if (join)
563 		ret = ip_mc_join_group(sk, &mreq);
564 	else
565 		ret = ip_mc_leave_group(sk, &mreq);
566 	release_sock(sk);
567 
568 	return ret;
569 }
570 
571 static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
572 {
573 	struct net *net = sock_net(skb->sk);
574 	struct nlattr *tb[IFA_MAX+1];
575 	struct in_device *in_dev;
576 	struct ifaddrmsg *ifm;
577 	struct in_ifaddr *ifa, **ifap;
578 	int err = -EINVAL;
579 
580 	ASSERT_RTNL();
581 
582 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy);
583 	if (err < 0)
584 		goto errout;
585 
586 	ifm = nlmsg_data(nlh);
587 	in_dev = inetdev_by_index(net, ifm->ifa_index);
588 	if (!in_dev) {
589 		err = -ENODEV;
590 		goto errout;
591 	}
592 
593 	for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
594 	     ifap = &ifa->ifa_next) {
595 		if (tb[IFA_LOCAL] &&
596 		    ifa->ifa_local != nla_get_in_addr(tb[IFA_LOCAL]))
597 			continue;
598 
599 		if (tb[IFA_LABEL] && nla_strcmp(tb[IFA_LABEL], ifa->ifa_label))
600 			continue;
601 
602 		if (tb[IFA_ADDRESS] &&
603 		    (ifm->ifa_prefixlen != ifa->ifa_prefixlen ||
604 		    !inet_ifa_match(nla_get_in_addr(tb[IFA_ADDRESS]), ifa)))
605 			continue;
606 
607 		if (ipv4_is_multicast(ifa->ifa_address))
608 			ip_mc_config(net->ipv4.mc_autojoin_sk, false, ifa);
609 		__inet_del_ifa(in_dev, ifap, 1, nlh, NETLINK_CB(skb).portid);
610 		return 0;
611 	}
612 
613 	err = -EADDRNOTAVAIL;
614 errout:
615 	return err;
616 }
617 
618 #define INFINITY_LIFE_TIME	0xFFFFFFFF
619 
620 static void check_lifetime(struct work_struct *work)
621 {
622 	unsigned long now, next, next_sec, next_sched;
623 	struct in_ifaddr *ifa;
624 	struct hlist_node *n;
625 	int i;
626 
627 	now = jiffies;
628 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
629 
630 	for (i = 0; i < IN4_ADDR_HSIZE; i++) {
631 		bool change_needed = false;
632 
633 		rcu_read_lock();
634 		hlist_for_each_entry_rcu(ifa, &inet_addr_lst[i], hash) {
635 			unsigned long age;
636 
637 			if (ifa->ifa_flags & IFA_F_PERMANENT)
638 				continue;
639 
640 			/* We try to batch several events at once. */
641 			age = (now - ifa->ifa_tstamp +
642 			       ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
643 
644 			if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME &&
645 			    age >= ifa->ifa_valid_lft) {
646 				change_needed = true;
647 			} else if (ifa->ifa_preferred_lft ==
648 				   INFINITY_LIFE_TIME) {
649 				continue;
650 			} else if (age >= ifa->ifa_preferred_lft) {
651 				if (time_before(ifa->ifa_tstamp +
652 						ifa->ifa_valid_lft * HZ, next))
653 					next = ifa->ifa_tstamp +
654 					       ifa->ifa_valid_lft * HZ;
655 
656 				if (!(ifa->ifa_flags & IFA_F_DEPRECATED))
657 					change_needed = true;
658 			} else if (time_before(ifa->ifa_tstamp +
659 					       ifa->ifa_preferred_lft * HZ,
660 					       next)) {
661 				next = ifa->ifa_tstamp +
662 				       ifa->ifa_preferred_lft * HZ;
663 			}
664 		}
665 		rcu_read_unlock();
666 		if (!change_needed)
667 			continue;
668 		rtnl_lock();
669 		hlist_for_each_entry_safe(ifa, n, &inet_addr_lst[i], hash) {
670 			unsigned long age;
671 
672 			if (ifa->ifa_flags & IFA_F_PERMANENT)
673 				continue;
674 
675 			/* We try to batch several events at once. */
676 			age = (now - ifa->ifa_tstamp +
677 			       ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
678 
679 			if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME &&
680 			    age >= ifa->ifa_valid_lft) {
681 				struct in_ifaddr **ifap;
682 
683 				for (ifap = &ifa->ifa_dev->ifa_list;
684 				     *ifap != NULL; ifap = &(*ifap)->ifa_next) {
685 					if (*ifap == ifa) {
686 						inet_del_ifa(ifa->ifa_dev,
687 							     ifap, 1);
688 						break;
689 					}
690 				}
691 			} else if (ifa->ifa_preferred_lft !=
692 				   INFINITY_LIFE_TIME &&
693 				   age >= ifa->ifa_preferred_lft &&
694 				   !(ifa->ifa_flags & IFA_F_DEPRECATED)) {
695 				ifa->ifa_flags |= IFA_F_DEPRECATED;
696 				rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);
697 			}
698 		}
699 		rtnl_unlock();
700 	}
701 
702 	next_sec = round_jiffies_up(next);
703 	next_sched = next;
704 
705 	/* If rounded timeout is accurate enough, accept it. */
706 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
707 		next_sched = next_sec;
708 
709 	now = jiffies;
710 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
711 	if (time_before(next_sched, now + ADDRCONF_TIMER_FUZZ_MAX))
712 		next_sched = now + ADDRCONF_TIMER_FUZZ_MAX;
713 
714 	queue_delayed_work(system_power_efficient_wq, &check_lifetime_work,
715 			next_sched - now);
716 }
717 
718 static void set_ifa_lifetime(struct in_ifaddr *ifa, __u32 valid_lft,
719 			     __u32 prefered_lft)
720 {
721 	unsigned long timeout;
722 
723 	ifa->ifa_flags &= ~(IFA_F_PERMANENT | IFA_F_DEPRECATED);
724 
725 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
726 	if (addrconf_finite_timeout(timeout))
727 		ifa->ifa_valid_lft = timeout;
728 	else
729 		ifa->ifa_flags |= IFA_F_PERMANENT;
730 
731 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
732 	if (addrconf_finite_timeout(timeout)) {
733 		if (timeout == 0)
734 			ifa->ifa_flags |= IFA_F_DEPRECATED;
735 		ifa->ifa_preferred_lft = timeout;
736 	}
737 	ifa->ifa_tstamp = jiffies;
738 	if (!ifa->ifa_cstamp)
739 		ifa->ifa_cstamp = ifa->ifa_tstamp;
740 }
741 
742 static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh,
743 				       __u32 *pvalid_lft, __u32 *pprefered_lft)
744 {
745 	struct nlattr *tb[IFA_MAX+1];
746 	struct in_ifaddr *ifa;
747 	struct ifaddrmsg *ifm;
748 	struct net_device *dev;
749 	struct in_device *in_dev;
750 	int err;
751 
752 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy);
753 	if (err < 0)
754 		goto errout;
755 
756 	ifm = nlmsg_data(nlh);
757 	err = -EINVAL;
758 	if (ifm->ifa_prefixlen > 32 || !tb[IFA_LOCAL])
759 		goto errout;
760 
761 	dev = __dev_get_by_index(net, ifm->ifa_index);
762 	err = -ENODEV;
763 	if (!dev)
764 		goto errout;
765 
766 	in_dev = __in_dev_get_rtnl(dev);
767 	err = -ENOBUFS;
768 	if (!in_dev)
769 		goto errout;
770 
771 	ifa = inet_alloc_ifa();
772 	if (!ifa)
773 		/*
774 		 * A potential indev allocation can be left alive, it stays
775 		 * assigned to its device and is destroy with it.
776 		 */
777 		goto errout;
778 
779 	ipv4_devconf_setall(in_dev);
780 	neigh_parms_data_state_setall(in_dev->arp_parms);
781 	in_dev_hold(in_dev);
782 
783 	if (!tb[IFA_ADDRESS])
784 		tb[IFA_ADDRESS] = tb[IFA_LOCAL];
785 
786 	INIT_HLIST_NODE(&ifa->hash);
787 	ifa->ifa_prefixlen = ifm->ifa_prefixlen;
788 	ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen);
789 	ifa->ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) :
790 					 ifm->ifa_flags;
791 	ifa->ifa_scope = ifm->ifa_scope;
792 	ifa->ifa_dev = in_dev;
793 
794 	ifa->ifa_local = nla_get_in_addr(tb[IFA_LOCAL]);
795 	ifa->ifa_address = nla_get_in_addr(tb[IFA_ADDRESS]);
796 
797 	if (tb[IFA_BROADCAST])
798 		ifa->ifa_broadcast = nla_get_in_addr(tb[IFA_BROADCAST]);
799 
800 	if (tb[IFA_LABEL])
801 		nla_strlcpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ);
802 	else
803 		memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
804 
805 	if (tb[IFA_CACHEINFO]) {
806 		struct ifa_cacheinfo *ci;
807 
808 		ci = nla_data(tb[IFA_CACHEINFO]);
809 		if (!ci->ifa_valid || ci->ifa_prefered > ci->ifa_valid) {
810 			err = -EINVAL;
811 			goto errout_free;
812 		}
813 		*pvalid_lft = ci->ifa_valid;
814 		*pprefered_lft = ci->ifa_prefered;
815 	}
816 
817 	return ifa;
818 
819 errout_free:
820 	inet_free_ifa(ifa);
821 errout:
822 	return ERR_PTR(err);
823 }
824 
825 static struct in_ifaddr *find_matching_ifa(struct in_ifaddr *ifa)
826 {
827 	struct in_device *in_dev = ifa->ifa_dev;
828 	struct in_ifaddr *ifa1, **ifap;
829 
830 	if (!ifa->ifa_local)
831 		return NULL;
832 
833 	for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL;
834 	     ifap = &ifa1->ifa_next) {
835 		if (ifa1->ifa_mask == ifa->ifa_mask &&
836 		    inet_ifa_match(ifa1->ifa_address, ifa) &&
837 		    ifa1->ifa_local == ifa->ifa_local)
838 			return ifa1;
839 	}
840 	return NULL;
841 }
842 
843 static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
844 {
845 	struct net *net = sock_net(skb->sk);
846 	struct in_ifaddr *ifa;
847 	struct in_ifaddr *ifa_existing;
848 	__u32 valid_lft = INFINITY_LIFE_TIME;
849 	__u32 prefered_lft = INFINITY_LIFE_TIME;
850 
851 	ASSERT_RTNL();
852 
853 	ifa = rtm_to_ifaddr(net, nlh, &valid_lft, &prefered_lft);
854 	if (IS_ERR(ifa))
855 		return PTR_ERR(ifa);
856 
857 	ifa_existing = find_matching_ifa(ifa);
858 	if (!ifa_existing) {
859 		/* It would be best to check for !NLM_F_CREATE here but
860 		 * userspace already relies on not having to provide this.
861 		 */
862 		set_ifa_lifetime(ifa, valid_lft, prefered_lft);
863 		if (ifa->ifa_flags & IFA_F_MCAUTOJOIN) {
864 			int ret = ip_mc_config(net->ipv4.mc_autojoin_sk,
865 					       true, ifa);
866 
867 			if (ret < 0) {
868 				inet_free_ifa(ifa);
869 				return ret;
870 			}
871 		}
872 		return __inet_insert_ifa(ifa, nlh, NETLINK_CB(skb).portid);
873 	} else {
874 		inet_free_ifa(ifa);
875 
876 		if (nlh->nlmsg_flags & NLM_F_EXCL ||
877 		    !(nlh->nlmsg_flags & NLM_F_REPLACE))
878 			return -EEXIST;
879 		ifa = ifa_existing;
880 		set_ifa_lifetime(ifa, valid_lft, prefered_lft);
881 		cancel_delayed_work(&check_lifetime_work);
882 		queue_delayed_work(system_power_efficient_wq,
883 				&check_lifetime_work, 0);
884 		rtmsg_ifa(RTM_NEWADDR, ifa, nlh, NETLINK_CB(skb).portid);
885 	}
886 	return 0;
887 }
888 
889 /*
890  *	Determine a default network mask, based on the IP address.
891  */
892 
893 static int inet_abc_len(__be32 addr)
894 {
895 	int rc = -1;	/* Something else, probably a multicast. */
896 
897 	if (ipv4_is_zeronet(addr))
898 		rc = 0;
899 	else {
900 		__u32 haddr = ntohl(addr);
901 
902 		if (IN_CLASSA(haddr))
903 			rc = 8;
904 		else if (IN_CLASSB(haddr))
905 			rc = 16;
906 		else if (IN_CLASSC(haddr))
907 			rc = 24;
908 	}
909 
910 	return rc;
911 }
912 
913 
914 int devinet_ioctl(struct net *net, unsigned int cmd, void __user *arg)
915 {
916 	struct ifreq ifr;
917 	struct sockaddr_in sin_orig;
918 	struct sockaddr_in *sin = (struct sockaddr_in *)&ifr.ifr_addr;
919 	struct in_device *in_dev;
920 	struct in_ifaddr **ifap = NULL;
921 	struct in_ifaddr *ifa = NULL;
922 	struct net_device *dev;
923 	char *colon;
924 	int ret = -EFAULT;
925 	int tryaddrmatch = 0;
926 
927 	/*
928 	 *	Fetch the caller's info block into kernel space
929 	 */
930 
931 	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
932 		goto out;
933 	ifr.ifr_name[IFNAMSIZ - 1] = 0;
934 
935 	/* save original address for comparison */
936 	memcpy(&sin_orig, sin, sizeof(*sin));
937 
938 	colon = strchr(ifr.ifr_name, ':');
939 	if (colon)
940 		*colon = 0;
941 
942 	dev_load(net, ifr.ifr_name);
943 
944 	switch (cmd) {
945 	case SIOCGIFADDR:	/* Get interface address */
946 	case SIOCGIFBRDADDR:	/* Get the broadcast address */
947 	case SIOCGIFDSTADDR:	/* Get the destination address */
948 	case SIOCGIFNETMASK:	/* Get the netmask for the interface */
949 		/* Note that these ioctls will not sleep,
950 		   so that we do not impose a lock.
951 		   One day we will be forced to put shlock here (I mean SMP)
952 		 */
953 		tryaddrmatch = (sin_orig.sin_family == AF_INET);
954 		memset(sin, 0, sizeof(*sin));
955 		sin->sin_family = AF_INET;
956 		break;
957 
958 	case SIOCSIFFLAGS:
959 		ret = -EPERM;
960 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
961 			goto out;
962 		break;
963 	case SIOCSIFADDR:	/* Set interface address (and family) */
964 	case SIOCSIFBRDADDR:	/* Set the broadcast address */
965 	case SIOCSIFDSTADDR:	/* Set the destination address */
966 	case SIOCSIFNETMASK: 	/* Set the netmask for the interface */
967 		ret = -EPERM;
968 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
969 			goto out;
970 		ret = -EINVAL;
971 		if (sin->sin_family != AF_INET)
972 			goto out;
973 		break;
974 	default:
975 		ret = -EINVAL;
976 		goto out;
977 	}
978 
979 	rtnl_lock();
980 
981 	ret = -ENODEV;
982 	dev = __dev_get_by_name(net, ifr.ifr_name);
983 	if (!dev)
984 		goto done;
985 
986 	if (colon)
987 		*colon = ':';
988 
989 	in_dev = __in_dev_get_rtnl(dev);
990 	if (in_dev) {
991 		if (tryaddrmatch) {
992 			/* Matthias Andree */
993 			/* compare label and address (4.4BSD style) */
994 			/* note: we only do this for a limited set of ioctls
995 			   and only if the original address family was AF_INET.
996 			   This is checked above. */
997 			for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
998 			     ifap = &ifa->ifa_next) {
999 				if (!strcmp(ifr.ifr_name, ifa->ifa_label) &&
1000 				    sin_orig.sin_addr.s_addr ==
1001 							ifa->ifa_local) {
1002 					break; /* found */
1003 				}
1004 			}
1005 		}
1006 		/* we didn't get a match, maybe the application is
1007 		   4.3BSD-style and passed in junk so we fall back to
1008 		   comparing just the label */
1009 		if (!ifa) {
1010 			for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
1011 			     ifap = &ifa->ifa_next)
1012 				if (!strcmp(ifr.ifr_name, ifa->ifa_label))
1013 					break;
1014 		}
1015 	}
1016 
1017 	ret = -EADDRNOTAVAIL;
1018 	if (!ifa && cmd != SIOCSIFADDR && cmd != SIOCSIFFLAGS)
1019 		goto done;
1020 
1021 	switch (cmd) {
1022 	case SIOCGIFADDR:	/* Get interface address */
1023 		sin->sin_addr.s_addr = ifa->ifa_local;
1024 		goto rarok;
1025 
1026 	case SIOCGIFBRDADDR:	/* Get the broadcast address */
1027 		sin->sin_addr.s_addr = ifa->ifa_broadcast;
1028 		goto rarok;
1029 
1030 	case SIOCGIFDSTADDR:	/* Get the destination address */
1031 		sin->sin_addr.s_addr = ifa->ifa_address;
1032 		goto rarok;
1033 
1034 	case SIOCGIFNETMASK:	/* Get the netmask for the interface */
1035 		sin->sin_addr.s_addr = ifa->ifa_mask;
1036 		goto rarok;
1037 
1038 	case SIOCSIFFLAGS:
1039 		if (colon) {
1040 			ret = -EADDRNOTAVAIL;
1041 			if (!ifa)
1042 				break;
1043 			ret = 0;
1044 			if (!(ifr.ifr_flags & IFF_UP))
1045 				inet_del_ifa(in_dev, ifap, 1);
1046 			break;
1047 		}
1048 		ret = dev_change_flags(dev, ifr.ifr_flags);
1049 		break;
1050 
1051 	case SIOCSIFADDR:	/* Set interface address (and family) */
1052 		ret = -EINVAL;
1053 		if (inet_abc_len(sin->sin_addr.s_addr) < 0)
1054 			break;
1055 
1056 		if (!ifa) {
1057 			ret = -ENOBUFS;
1058 			ifa = inet_alloc_ifa();
1059 			if (!ifa)
1060 				break;
1061 			INIT_HLIST_NODE(&ifa->hash);
1062 			if (colon)
1063 				memcpy(ifa->ifa_label, ifr.ifr_name, IFNAMSIZ);
1064 			else
1065 				memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1066 		} else {
1067 			ret = 0;
1068 			if (ifa->ifa_local == sin->sin_addr.s_addr)
1069 				break;
1070 			inet_del_ifa(in_dev, ifap, 0);
1071 			ifa->ifa_broadcast = 0;
1072 			ifa->ifa_scope = 0;
1073 		}
1074 
1075 		ifa->ifa_address = ifa->ifa_local = sin->sin_addr.s_addr;
1076 
1077 		if (!(dev->flags & IFF_POINTOPOINT)) {
1078 			ifa->ifa_prefixlen = inet_abc_len(ifa->ifa_address);
1079 			ifa->ifa_mask = inet_make_mask(ifa->ifa_prefixlen);
1080 			if ((dev->flags & IFF_BROADCAST) &&
1081 			    ifa->ifa_prefixlen < 31)
1082 				ifa->ifa_broadcast = ifa->ifa_address |
1083 						     ~ifa->ifa_mask;
1084 		} else {
1085 			ifa->ifa_prefixlen = 32;
1086 			ifa->ifa_mask = inet_make_mask(32);
1087 		}
1088 		set_ifa_lifetime(ifa, INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
1089 		ret = inet_set_ifa(dev, ifa);
1090 		break;
1091 
1092 	case SIOCSIFBRDADDR:	/* Set the broadcast address */
1093 		ret = 0;
1094 		if (ifa->ifa_broadcast != sin->sin_addr.s_addr) {
1095 			inet_del_ifa(in_dev, ifap, 0);
1096 			ifa->ifa_broadcast = sin->sin_addr.s_addr;
1097 			inet_insert_ifa(ifa);
1098 		}
1099 		break;
1100 
1101 	case SIOCSIFDSTADDR:	/* Set the destination address */
1102 		ret = 0;
1103 		if (ifa->ifa_address == sin->sin_addr.s_addr)
1104 			break;
1105 		ret = -EINVAL;
1106 		if (inet_abc_len(sin->sin_addr.s_addr) < 0)
1107 			break;
1108 		ret = 0;
1109 		inet_del_ifa(in_dev, ifap, 0);
1110 		ifa->ifa_address = sin->sin_addr.s_addr;
1111 		inet_insert_ifa(ifa);
1112 		break;
1113 
1114 	case SIOCSIFNETMASK: 	/* Set the netmask for the interface */
1115 
1116 		/*
1117 		 *	The mask we set must be legal.
1118 		 */
1119 		ret = -EINVAL;
1120 		if (bad_mask(sin->sin_addr.s_addr, 0))
1121 			break;
1122 		ret = 0;
1123 		if (ifa->ifa_mask != sin->sin_addr.s_addr) {
1124 			__be32 old_mask = ifa->ifa_mask;
1125 			inet_del_ifa(in_dev, ifap, 0);
1126 			ifa->ifa_mask = sin->sin_addr.s_addr;
1127 			ifa->ifa_prefixlen = inet_mask_len(ifa->ifa_mask);
1128 
1129 			/* See if current broadcast address matches
1130 			 * with current netmask, then recalculate
1131 			 * the broadcast address. Otherwise it's a
1132 			 * funny address, so don't touch it since
1133 			 * the user seems to know what (s)he's doing...
1134 			 */
1135 			if ((dev->flags & IFF_BROADCAST) &&
1136 			    (ifa->ifa_prefixlen < 31) &&
1137 			    (ifa->ifa_broadcast ==
1138 			     (ifa->ifa_local|~old_mask))) {
1139 				ifa->ifa_broadcast = (ifa->ifa_local |
1140 						      ~sin->sin_addr.s_addr);
1141 			}
1142 			inet_insert_ifa(ifa);
1143 		}
1144 		break;
1145 	}
1146 done:
1147 	rtnl_unlock();
1148 out:
1149 	return ret;
1150 rarok:
1151 	rtnl_unlock();
1152 	ret = copy_to_user(arg, &ifr, sizeof(struct ifreq)) ? -EFAULT : 0;
1153 	goto out;
1154 }
1155 
1156 static int inet_gifconf(struct net_device *dev, char __user *buf, int len)
1157 {
1158 	struct in_device *in_dev = __in_dev_get_rtnl(dev);
1159 	struct in_ifaddr *ifa;
1160 	struct ifreq ifr;
1161 	int done = 0;
1162 
1163 	if (!in_dev)
1164 		goto out;
1165 
1166 	for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
1167 		if (!buf) {
1168 			done += sizeof(ifr);
1169 			continue;
1170 		}
1171 		if (len < (int) sizeof(ifr))
1172 			break;
1173 		memset(&ifr, 0, sizeof(struct ifreq));
1174 		strcpy(ifr.ifr_name, ifa->ifa_label);
1175 
1176 		(*(struct sockaddr_in *)&ifr.ifr_addr).sin_family = AF_INET;
1177 		(*(struct sockaddr_in *)&ifr.ifr_addr).sin_addr.s_addr =
1178 								ifa->ifa_local;
1179 
1180 		if (copy_to_user(buf, &ifr, sizeof(struct ifreq))) {
1181 			done = -EFAULT;
1182 			break;
1183 		}
1184 		buf  += sizeof(struct ifreq);
1185 		len  -= sizeof(struct ifreq);
1186 		done += sizeof(struct ifreq);
1187 	}
1188 out:
1189 	return done;
1190 }
1191 
1192 __be32 inet_select_addr(const struct net_device *dev, __be32 dst, int scope)
1193 {
1194 	__be32 addr = 0;
1195 	struct in_device *in_dev;
1196 	struct net *net = dev_net(dev);
1197 
1198 	rcu_read_lock();
1199 	in_dev = __in_dev_get_rcu(dev);
1200 	if (!in_dev)
1201 		goto no_in_dev;
1202 
1203 	for_primary_ifa(in_dev) {
1204 		if (ifa->ifa_scope > scope)
1205 			continue;
1206 		if (!dst || inet_ifa_match(dst, ifa)) {
1207 			addr = ifa->ifa_local;
1208 			break;
1209 		}
1210 		if (!addr)
1211 			addr = ifa->ifa_local;
1212 	} endfor_ifa(in_dev);
1213 
1214 	if (addr)
1215 		goto out_unlock;
1216 no_in_dev:
1217 
1218 	/* Not loopback addresses on loopback should be preferred
1219 	   in this case. It is important that lo is the first interface
1220 	   in dev_base list.
1221 	 */
1222 	for_each_netdev_rcu(net, dev) {
1223 		in_dev = __in_dev_get_rcu(dev);
1224 		if (!in_dev)
1225 			continue;
1226 
1227 		for_primary_ifa(in_dev) {
1228 			if (ifa->ifa_scope != RT_SCOPE_LINK &&
1229 			    ifa->ifa_scope <= scope) {
1230 				addr = ifa->ifa_local;
1231 				goto out_unlock;
1232 			}
1233 		} endfor_ifa(in_dev);
1234 	}
1235 out_unlock:
1236 	rcu_read_unlock();
1237 	return addr;
1238 }
1239 EXPORT_SYMBOL(inet_select_addr);
1240 
1241 static __be32 confirm_addr_indev(struct in_device *in_dev, __be32 dst,
1242 			      __be32 local, int scope)
1243 {
1244 	int same = 0;
1245 	__be32 addr = 0;
1246 
1247 	for_ifa(in_dev) {
1248 		if (!addr &&
1249 		    (local == ifa->ifa_local || !local) &&
1250 		    ifa->ifa_scope <= scope) {
1251 			addr = ifa->ifa_local;
1252 			if (same)
1253 				break;
1254 		}
1255 		if (!same) {
1256 			same = (!local || inet_ifa_match(local, ifa)) &&
1257 				(!dst || inet_ifa_match(dst, ifa));
1258 			if (same && addr) {
1259 				if (local || !dst)
1260 					break;
1261 				/* Is the selected addr into dst subnet? */
1262 				if (inet_ifa_match(addr, ifa))
1263 					break;
1264 				/* No, then can we use new local src? */
1265 				if (ifa->ifa_scope <= scope) {
1266 					addr = ifa->ifa_local;
1267 					break;
1268 				}
1269 				/* search for large dst subnet for addr */
1270 				same = 0;
1271 			}
1272 		}
1273 	} endfor_ifa(in_dev);
1274 
1275 	return same ? addr : 0;
1276 }
1277 
1278 /*
1279  * Confirm that local IP address exists using wildcards:
1280  * - net: netns to check, cannot be NULL
1281  * - in_dev: only on this interface, NULL=any interface
1282  * - dst: only in the same subnet as dst, 0=any dst
1283  * - local: address, 0=autoselect the local address
1284  * - scope: maximum allowed scope value for the local address
1285  */
1286 __be32 inet_confirm_addr(struct net *net, struct in_device *in_dev,
1287 			 __be32 dst, __be32 local, int scope)
1288 {
1289 	__be32 addr = 0;
1290 	struct net_device *dev;
1291 
1292 	if (in_dev)
1293 		return confirm_addr_indev(in_dev, dst, local, scope);
1294 
1295 	rcu_read_lock();
1296 	for_each_netdev_rcu(net, dev) {
1297 		in_dev = __in_dev_get_rcu(dev);
1298 		if (in_dev) {
1299 			addr = confirm_addr_indev(in_dev, dst, local, scope);
1300 			if (addr)
1301 				break;
1302 		}
1303 	}
1304 	rcu_read_unlock();
1305 
1306 	return addr;
1307 }
1308 EXPORT_SYMBOL(inet_confirm_addr);
1309 
1310 /*
1311  *	Device notifier
1312  */
1313 
1314 int register_inetaddr_notifier(struct notifier_block *nb)
1315 {
1316 	return blocking_notifier_chain_register(&inetaddr_chain, nb);
1317 }
1318 EXPORT_SYMBOL(register_inetaddr_notifier);
1319 
1320 int unregister_inetaddr_notifier(struct notifier_block *nb)
1321 {
1322 	return blocking_notifier_chain_unregister(&inetaddr_chain, nb);
1323 }
1324 EXPORT_SYMBOL(unregister_inetaddr_notifier);
1325 
1326 /* Rename ifa_labels for a device name change. Make some effort to preserve
1327  * existing alias numbering and to create unique labels if possible.
1328 */
1329 static void inetdev_changename(struct net_device *dev, struct in_device *in_dev)
1330 {
1331 	struct in_ifaddr *ifa;
1332 	int named = 0;
1333 
1334 	for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
1335 		char old[IFNAMSIZ], *dot;
1336 
1337 		memcpy(old, ifa->ifa_label, IFNAMSIZ);
1338 		memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1339 		if (named++ == 0)
1340 			goto skip;
1341 		dot = strchr(old, ':');
1342 		if (!dot) {
1343 			sprintf(old, ":%d", named);
1344 			dot = old;
1345 		}
1346 		if (strlen(dot) + strlen(dev->name) < IFNAMSIZ)
1347 			strcat(ifa->ifa_label, dot);
1348 		else
1349 			strcpy(ifa->ifa_label + (IFNAMSIZ - strlen(dot) - 1), dot);
1350 skip:
1351 		rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);
1352 	}
1353 }
1354 
1355 static bool inetdev_valid_mtu(unsigned int mtu)
1356 {
1357 	return mtu >= 68;
1358 }
1359 
1360 static void inetdev_send_gratuitous_arp(struct net_device *dev,
1361 					struct in_device *in_dev)
1362 
1363 {
1364 	struct in_ifaddr *ifa;
1365 
1366 	for (ifa = in_dev->ifa_list; ifa;
1367 	     ifa = ifa->ifa_next) {
1368 		arp_send(ARPOP_REQUEST, ETH_P_ARP,
1369 			 ifa->ifa_local, dev,
1370 			 ifa->ifa_local, NULL,
1371 			 dev->dev_addr, NULL);
1372 	}
1373 }
1374 
1375 /* Called only under RTNL semaphore */
1376 
1377 static int inetdev_event(struct notifier_block *this, unsigned long event,
1378 			 void *ptr)
1379 {
1380 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1381 	struct in_device *in_dev = __in_dev_get_rtnl(dev);
1382 
1383 	ASSERT_RTNL();
1384 
1385 	if (!in_dev) {
1386 		if (event == NETDEV_REGISTER) {
1387 			in_dev = inetdev_init(dev);
1388 			if (IS_ERR(in_dev))
1389 				return notifier_from_errno(PTR_ERR(in_dev));
1390 			if (dev->flags & IFF_LOOPBACK) {
1391 				IN_DEV_CONF_SET(in_dev, NOXFRM, 1);
1392 				IN_DEV_CONF_SET(in_dev, NOPOLICY, 1);
1393 			}
1394 		} else if (event == NETDEV_CHANGEMTU) {
1395 			/* Re-enabling IP */
1396 			if (inetdev_valid_mtu(dev->mtu))
1397 				in_dev = inetdev_init(dev);
1398 		}
1399 		goto out;
1400 	}
1401 
1402 	switch (event) {
1403 	case NETDEV_REGISTER:
1404 		pr_debug("%s: bug\n", __func__);
1405 		RCU_INIT_POINTER(dev->ip_ptr, NULL);
1406 		break;
1407 	case NETDEV_UP:
1408 		if (!inetdev_valid_mtu(dev->mtu))
1409 			break;
1410 		if (dev->flags & IFF_LOOPBACK) {
1411 			struct in_ifaddr *ifa = inet_alloc_ifa();
1412 
1413 			if (ifa) {
1414 				INIT_HLIST_NODE(&ifa->hash);
1415 				ifa->ifa_local =
1416 				  ifa->ifa_address = htonl(INADDR_LOOPBACK);
1417 				ifa->ifa_prefixlen = 8;
1418 				ifa->ifa_mask = inet_make_mask(8);
1419 				in_dev_hold(in_dev);
1420 				ifa->ifa_dev = in_dev;
1421 				ifa->ifa_scope = RT_SCOPE_HOST;
1422 				memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1423 				set_ifa_lifetime(ifa, INFINITY_LIFE_TIME,
1424 						 INFINITY_LIFE_TIME);
1425 				ipv4_devconf_setall(in_dev);
1426 				neigh_parms_data_state_setall(in_dev->arp_parms);
1427 				inet_insert_ifa(ifa);
1428 			}
1429 		}
1430 		ip_mc_up(in_dev);
1431 		/* fall through */
1432 	case NETDEV_CHANGEADDR:
1433 		if (!IN_DEV_ARP_NOTIFY(in_dev))
1434 			break;
1435 		/* fall through */
1436 	case NETDEV_NOTIFY_PEERS:
1437 		/* Send gratuitous ARP to notify of link change */
1438 		inetdev_send_gratuitous_arp(dev, in_dev);
1439 		break;
1440 	case NETDEV_DOWN:
1441 		ip_mc_down(in_dev);
1442 		break;
1443 	case NETDEV_PRE_TYPE_CHANGE:
1444 		ip_mc_unmap(in_dev);
1445 		break;
1446 	case NETDEV_POST_TYPE_CHANGE:
1447 		ip_mc_remap(in_dev);
1448 		break;
1449 	case NETDEV_CHANGEMTU:
1450 		if (inetdev_valid_mtu(dev->mtu))
1451 			break;
1452 		/* disable IP when MTU is not enough */
1453 	case NETDEV_UNREGISTER:
1454 		inetdev_destroy(in_dev);
1455 		break;
1456 	case NETDEV_CHANGENAME:
1457 		/* Do not notify about label change, this event is
1458 		 * not interesting to applications using netlink.
1459 		 */
1460 		inetdev_changename(dev, in_dev);
1461 
1462 		devinet_sysctl_unregister(in_dev);
1463 		devinet_sysctl_register(in_dev);
1464 		break;
1465 	}
1466 out:
1467 	return NOTIFY_DONE;
1468 }
1469 
1470 static struct notifier_block ip_netdev_notifier = {
1471 	.notifier_call = inetdev_event,
1472 };
1473 
1474 static size_t inet_nlmsg_size(void)
1475 {
1476 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
1477 	       + nla_total_size(4) /* IFA_ADDRESS */
1478 	       + nla_total_size(4) /* IFA_LOCAL */
1479 	       + nla_total_size(4) /* IFA_BROADCAST */
1480 	       + nla_total_size(IFNAMSIZ) /* IFA_LABEL */
1481 	       + nla_total_size(4)  /* IFA_FLAGS */
1482 	       + nla_total_size(sizeof(struct ifa_cacheinfo)); /* IFA_CACHEINFO */
1483 }
1484 
1485 static inline u32 cstamp_delta(unsigned long cstamp)
1486 {
1487 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
1488 }
1489 
1490 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
1491 			 unsigned long tstamp, u32 preferred, u32 valid)
1492 {
1493 	struct ifa_cacheinfo ci;
1494 
1495 	ci.cstamp = cstamp_delta(cstamp);
1496 	ci.tstamp = cstamp_delta(tstamp);
1497 	ci.ifa_prefered = preferred;
1498 	ci.ifa_valid = valid;
1499 
1500 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
1501 }
1502 
1503 static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa,
1504 			    u32 portid, u32 seq, int event, unsigned int flags)
1505 {
1506 	struct ifaddrmsg *ifm;
1507 	struct nlmsghdr  *nlh;
1508 	u32 preferred, valid;
1509 
1510 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*ifm), flags);
1511 	if (!nlh)
1512 		return -EMSGSIZE;
1513 
1514 	ifm = nlmsg_data(nlh);
1515 	ifm->ifa_family = AF_INET;
1516 	ifm->ifa_prefixlen = ifa->ifa_prefixlen;
1517 	ifm->ifa_flags = ifa->ifa_flags;
1518 	ifm->ifa_scope = ifa->ifa_scope;
1519 	ifm->ifa_index = ifa->ifa_dev->dev->ifindex;
1520 
1521 	if (!(ifm->ifa_flags & IFA_F_PERMANENT)) {
1522 		preferred = ifa->ifa_preferred_lft;
1523 		valid = ifa->ifa_valid_lft;
1524 		if (preferred != INFINITY_LIFE_TIME) {
1525 			long tval = (jiffies - ifa->ifa_tstamp) / HZ;
1526 
1527 			if (preferred > tval)
1528 				preferred -= tval;
1529 			else
1530 				preferred = 0;
1531 			if (valid != INFINITY_LIFE_TIME) {
1532 				if (valid > tval)
1533 					valid -= tval;
1534 				else
1535 					valid = 0;
1536 			}
1537 		}
1538 	} else {
1539 		preferred = INFINITY_LIFE_TIME;
1540 		valid = INFINITY_LIFE_TIME;
1541 	}
1542 	if ((ifa->ifa_address &&
1543 	     nla_put_in_addr(skb, IFA_ADDRESS, ifa->ifa_address)) ||
1544 	    (ifa->ifa_local &&
1545 	     nla_put_in_addr(skb, IFA_LOCAL, ifa->ifa_local)) ||
1546 	    (ifa->ifa_broadcast &&
1547 	     nla_put_in_addr(skb, IFA_BROADCAST, ifa->ifa_broadcast)) ||
1548 	    (ifa->ifa_label[0] &&
1549 	     nla_put_string(skb, IFA_LABEL, ifa->ifa_label)) ||
1550 	    nla_put_u32(skb, IFA_FLAGS, ifa->ifa_flags) ||
1551 	    put_cacheinfo(skb, ifa->ifa_cstamp, ifa->ifa_tstamp,
1552 			  preferred, valid))
1553 		goto nla_put_failure;
1554 
1555 	nlmsg_end(skb, nlh);
1556 	return 0;
1557 
1558 nla_put_failure:
1559 	nlmsg_cancel(skb, nlh);
1560 	return -EMSGSIZE;
1561 }
1562 
1563 static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
1564 {
1565 	struct net *net = sock_net(skb->sk);
1566 	int h, s_h;
1567 	int idx, s_idx;
1568 	int ip_idx, s_ip_idx;
1569 	struct net_device *dev;
1570 	struct in_device *in_dev;
1571 	struct in_ifaddr *ifa;
1572 	struct hlist_head *head;
1573 
1574 	s_h = cb->args[0];
1575 	s_idx = idx = cb->args[1];
1576 	s_ip_idx = ip_idx = cb->args[2];
1577 
1578 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
1579 		idx = 0;
1580 		head = &net->dev_index_head[h];
1581 		rcu_read_lock();
1582 		cb->seq = atomic_read(&net->ipv4.dev_addr_genid) ^
1583 			  net->dev_base_seq;
1584 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
1585 			if (idx < s_idx)
1586 				goto cont;
1587 			if (h > s_h || idx > s_idx)
1588 				s_ip_idx = 0;
1589 			in_dev = __in_dev_get_rcu(dev);
1590 			if (!in_dev)
1591 				goto cont;
1592 
1593 			for (ifa = in_dev->ifa_list, ip_idx = 0; ifa;
1594 			     ifa = ifa->ifa_next, ip_idx++) {
1595 				if (ip_idx < s_ip_idx)
1596 					continue;
1597 				if (inet_fill_ifaddr(skb, ifa,
1598 					     NETLINK_CB(cb->skb).portid,
1599 					     cb->nlh->nlmsg_seq,
1600 					     RTM_NEWADDR, NLM_F_MULTI) < 0) {
1601 					rcu_read_unlock();
1602 					goto done;
1603 				}
1604 				nl_dump_check_consistent(cb, nlmsg_hdr(skb));
1605 			}
1606 cont:
1607 			idx++;
1608 		}
1609 		rcu_read_unlock();
1610 	}
1611 
1612 done:
1613 	cb->args[0] = h;
1614 	cb->args[1] = idx;
1615 	cb->args[2] = ip_idx;
1616 
1617 	return skb->len;
1618 }
1619 
1620 static void rtmsg_ifa(int event, struct in_ifaddr *ifa, struct nlmsghdr *nlh,
1621 		      u32 portid)
1622 {
1623 	struct sk_buff *skb;
1624 	u32 seq = nlh ? nlh->nlmsg_seq : 0;
1625 	int err = -ENOBUFS;
1626 	struct net *net;
1627 
1628 	net = dev_net(ifa->ifa_dev->dev);
1629 	skb = nlmsg_new(inet_nlmsg_size(), GFP_KERNEL);
1630 	if (!skb)
1631 		goto errout;
1632 
1633 	err = inet_fill_ifaddr(skb, ifa, portid, seq, event, 0);
1634 	if (err < 0) {
1635 		/* -EMSGSIZE implies BUG in inet_nlmsg_size() */
1636 		WARN_ON(err == -EMSGSIZE);
1637 		kfree_skb(skb);
1638 		goto errout;
1639 	}
1640 	rtnl_notify(skb, net, portid, RTNLGRP_IPV4_IFADDR, nlh, GFP_KERNEL);
1641 	return;
1642 errout:
1643 	if (err < 0)
1644 		rtnl_set_sk_err(net, RTNLGRP_IPV4_IFADDR, err);
1645 }
1646 
1647 static size_t inet_get_link_af_size(const struct net_device *dev)
1648 {
1649 	struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr);
1650 
1651 	if (!in_dev)
1652 		return 0;
1653 
1654 	return nla_total_size(IPV4_DEVCONF_MAX * 4); /* IFLA_INET_CONF */
1655 }
1656 
1657 static int inet_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
1658 {
1659 	struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr);
1660 	struct nlattr *nla;
1661 	int i;
1662 
1663 	if (!in_dev)
1664 		return -ENODATA;
1665 
1666 	nla = nla_reserve(skb, IFLA_INET_CONF, IPV4_DEVCONF_MAX * 4);
1667 	if (!nla)
1668 		return -EMSGSIZE;
1669 
1670 	for (i = 0; i < IPV4_DEVCONF_MAX; i++)
1671 		((u32 *) nla_data(nla))[i] = in_dev->cnf.data[i];
1672 
1673 	return 0;
1674 }
1675 
1676 static const struct nla_policy inet_af_policy[IFLA_INET_MAX+1] = {
1677 	[IFLA_INET_CONF]	= { .type = NLA_NESTED },
1678 };
1679 
1680 static int inet_validate_link_af(const struct net_device *dev,
1681 				 const struct nlattr *nla)
1682 {
1683 	struct nlattr *a, *tb[IFLA_INET_MAX+1];
1684 	int err, rem;
1685 
1686 	if (dev && !__in_dev_get_rtnl(dev))
1687 		return -EAFNOSUPPORT;
1688 
1689 	err = nla_parse_nested(tb, IFLA_INET_MAX, nla, inet_af_policy);
1690 	if (err < 0)
1691 		return err;
1692 
1693 	if (tb[IFLA_INET_CONF]) {
1694 		nla_for_each_nested(a, tb[IFLA_INET_CONF], rem) {
1695 			int cfgid = nla_type(a);
1696 
1697 			if (nla_len(a) < 4)
1698 				return -EINVAL;
1699 
1700 			if (cfgid <= 0 || cfgid > IPV4_DEVCONF_MAX)
1701 				return -EINVAL;
1702 		}
1703 	}
1704 
1705 	return 0;
1706 }
1707 
1708 static int inet_set_link_af(struct net_device *dev, const struct nlattr *nla)
1709 {
1710 	struct in_device *in_dev = __in_dev_get_rtnl(dev);
1711 	struct nlattr *a, *tb[IFLA_INET_MAX+1];
1712 	int rem;
1713 
1714 	if (!in_dev)
1715 		return -EAFNOSUPPORT;
1716 
1717 	if (nla_parse_nested(tb, IFLA_INET_MAX, nla, NULL) < 0)
1718 		BUG();
1719 
1720 	if (tb[IFLA_INET_CONF]) {
1721 		nla_for_each_nested(a, tb[IFLA_INET_CONF], rem)
1722 			ipv4_devconf_set(in_dev, nla_type(a), nla_get_u32(a));
1723 	}
1724 
1725 	return 0;
1726 }
1727 
1728 static int inet_netconf_msgsize_devconf(int type)
1729 {
1730 	int size = NLMSG_ALIGN(sizeof(struct netconfmsg))
1731 		   + nla_total_size(4);	/* NETCONFA_IFINDEX */
1732 
1733 	/* type -1 is used for ALL */
1734 	if (type == -1 || type == NETCONFA_FORWARDING)
1735 		size += nla_total_size(4);
1736 	if (type == -1 || type == NETCONFA_RP_FILTER)
1737 		size += nla_total_size(4);
1738 	if (type == -1 || type == NETCONFA_MC_FORWARDING)
1739 		size += nla_total_size(4);
1740 	if (type == -1 || type == NETCONFA_PROXY_NEIGH)
1741 		size += nla_total_size(4);
1742 	if (type == -1 || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
1743 		size += nla_total_size(4);
1744 
1745 	return size;
1746 }
1747 
1748 static int inet_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
1749 				     struct ipv4_devconf *devconf, u32 portid,
1750 				     u32 seq, int event, unsigned int flags,
1751 				     int type)
1752 {
1753 	struct nlmsghdr  *nlh;
1754 	struct netconfmsg *ncm;
1755 
1756 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
1757 			flags);
1758 	if (!nlh)
1759 		return -EMSGSIZE;
1760 
1761 	ncm = nlmsg_data(nlh);
1762 	ncm->ncm_family = AF_INET;
1763 
1764 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
1765 		goto nla_put_failure;
1766 
1767 	/* type -1 is used for ALL */
1768 	if ((type == -1 || type == NETCONFA_FORWARDING) &&
1769 	    nla_put_s32(skb, NETCONFA_FORWARDING,
1770 			IPV4_DEVCONF(*devconf, FORWARDING)) < 0)
1771 		goto nla_put_failure;
1772 	if ((type == -1 || type == NETCONFA_RP_FILTER) &&
1773 	    nla_put_s32(skb, NETCONFA_RP_FILTER,
1774 			IPV4_DEVCONF(*devconf, RP_FILTER)) < 0)
1775 		goto nla_put_failure;
1776 	if ((type == -1 || type == NETCONFA_MC_FORWARDING) &&
1777 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
1778 			IPV4_DEVCONF(*devconf, MC_FORWARDING)) < 0)
1779 		goto nla_put_failure;
1780 	if ((type == -1 || type == NETCONFA_PROXY_NEIGH) &&
1781 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH,
1782 			IPV4_DEVCONF(*devconf, PROXY_ARP)) < 0)
1783 		goto nla_put_failure;
1784 	if ((type == -1 || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
1785 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
1786 			IPV4_DEVCONF(*devconf, IGNORE_ROUTES_WITH_LINKDOWN)) < 0)
1787 		goto nla_put_failure;
1788 
1789 	nlmsg_end(skb, nlh);
1790 	return 0;
1791 
1792 nla_put_failure:
1793 	nlmsg_cancel(skb, nlh);
1794 	return -EMSGSIZE;
1795 }
1796 
1797 void inet_netconf_notify_devconf(struct net *net, int type, int ifindex,
1798 				 struct ipv4_devconf *devconf)
1799 {
1800 	struct sk_buff *skb;
1801 	int err = -ENOBUFS;
1802 
1803 	skb = nlmsg_new(inet_netconf_msgsize_devconf(type), GFP_ATOMIC);
1804 	if (!skb)
1805 		goto errout;
1806 
1807 	err = inet_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
1808 					RTM_NEWNETCONF, 0, type);
1809 	if (err < 0) {
1810 		/* -EMSGSIZE implies BUG in inet_netconf_msgsize_devconf() */
1811 		WARN_ON(err == -EMSGSIZE);
1812 		kfree_skb(skb);
1813 		goto errout;
1814 	}
1815 	rtnl_notify(skb, net, 0, RTNLGRP_IPV4_NETCONF, NULL, GFP_ATOMIC);
1816 	return;
1817 errout:
1818 	if (err < 0)
1819 		rtnl_set_sk_err(net, RTNLGRP_IPV4_NETCONF, err);
1820 }
1821 
1822 static const struct nla_policy devconf_ipv4_policy[NETCONFA_MAX+1] = {
1823 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
1824 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
1825 	[NETCONFA_RP_FILTER]	= { .len = sizeof(int) },
1826 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
1827 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
1828 };
1829 
1830 static int inet_netconf_get_devconf(struct sk_buff *in_skb,
1831 				    struct nlmsghdr *nlh)
1832 {
1833 	struct net *net = sock_net(in_skb->sk);
1834 	struct nlattr *tb[NETCONFA_MAX+1];
1835 	struct netconfmsg *ncm;
1836 	struct sk_buff *skb;
1837 	struct ipv4_devconf *devconf;
1838 	struct in_device *in_dev;
1839 	struct net_device *dev;
1840 	int ifindex;
1841 	int err;
1842 
1843 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
1844 			  devconf_ipv4_policy);
1845 	if (err < 0)
1846 		goto errout;
1847 
1848 	err = EINVAL;
1849 	if (!tb[NETCONFA_IFINDEX])
1850 		goto errout;
1851 
1852 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
1853 	switch (ifindex) {
1854 	case NETCONFA_IFINDEX_ALL:
1855 		devconf = net->ipv4.devconf_all;
1856 		break;
1857 	case NETCONFA_IFINDEX_DEFAULT:
1858 		devconf = net->ipv4.devconf_dflt;
1859 		break;
1860 	default:
1861 		dev = __dev_get_by_index(net, ifindex);
1862 		if (!dev)
1863 			goto errout;
1864 		in_dev = __in_dev_get_rtnl(dev);
1865 		if (!in_dev)
1866 			goto errout;
1867 		devconf = &in_dev->cnf;
1868 		break;
1869 	}
1870 
1871 	err = -ENOBUFS;
1872 	skb = nlmsg_new(inet_netconf_msgsize_devconf(-1), GFP_ATOMIC);
1873 	if (!skb)
1874 		goto errout;
1875 
1876 	err = inet_netconf_fill_devconf(skb, ifindex, devconf,
1877 					NETLINK_CB(in_skb).portid,
1878 					nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
1879 					-1);
1880 	if (err < 0) {
1881 		/* -EMSGSIZE implies BUG in inet_netconf_msgsize_devconf() */
1882 		WARN_ON(err == -EMSGSIZE);
1883 		kfree_skb(skb);
1884 		goto errout;
1885 	}
1886 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
1887 errout:
1888 	return err;
1889 }
1890 
1891 static int inet_netconf_dump_devconf(struct sk_buff *skb,
1892 				     struct netlink_callback *cb)
1893 {
1894 	struct net *net = sock_net(skb->sk);
1895 	int h, s_h;
1896 	int idx, s_idx;
1897 	struct net_device *dev;
1898 	struct in_device *in_dev;
1899 	struct hlist_head *head;
1900 
1901 	s_h = cb->args[0];
1902 	s_idx = idx = cb->args[1];
1903 
1904 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
1905 		idx = 0;
1906 		head = &net->dev_index_head[h];
1907 		rcu_read_lock();
1908 		cb->seq = atomic_read(&net->ipv4.dev_addr_genid) ^
1909 			  net->dev_base_seq;
1910 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
1911 			if (idx < s_idx)
1912 				goto cont;
1913 			in_dev = __in_dev_get_rcu(dev);
1914 			if (!in_dev)
1915 				goto cont;
1916 
1917 			if (inet_netconf_fill_devconf(skb, dev->ifindex,
1918 						      &in_dev->cnf,
1919 						      NETLINK_CB(cb->skb).portid,
1920 						      cb->nlh->nlmsg_seq,
1921 						      RTM_NEWNETCONF,
1922 						      NLM_F_MULTI,
1923 						      -1) < 0) {
1924 				rcu_read_unlock();
1925 				goto done;
1926 			}
1927 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
1928 cont:
1929 			idx++;
1930 		}
1931 		rcu_read_unlock();
1932 	}
1933 	if (h == NETDEV_HASHENTRIES) {
1934 		if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
1935 					      net->ipv4.devconf_all,
1936 					      NETLINK_CB(cb->skb).portid,
1937 					      cb->nlh->nlmsg_seq,
1938 					      RTM_NEWNETCONF, NLM_F_MULTI,
1939 					      -1) < 0)
1940 			goto done;
1941 		else
1942 			h++;
1943 	}
1944 	if (h == NETDEV_HASHENTRIES + 1) {
1945 		if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
1946 					      net->ipv4.devconf_dflt,
1947 					      NETLINK_CB(cb->skb).portid,
1948 					      cb->nlh->nlmsg_seq,
1949 					      RTM_NEWNETCONF, NLM_F_MULTI,
1950 					      -1) < 0)
1951 			goto done;
1952 		else
1953 			h++;
1954 	}
1955 done:
1956 	cb->args[0] = h;
1957 	cb->args[1] = idx;
1958 
1959 	return skb->len;
1960 }
1961 
1962 #ifdef CONFIG_SYSCTL
1963 
1964 static void devinet_copy_dflt_conf(struct net *net, int i)
1965 {
1966 	struct net_device *dev;
1967 
1968 	rcu_read_lock();
1969 	for_each_netdev_rcu(net, dev) {
1970 		struct in_device *in_dev;
1971 
1972 		in_dev = __in_dev_get_rcu(dev);
1973 		if (in_dev && !test_bit(i, in_dev->cnf.state))
1974 			in_dev->cnf.data[i] = net->ipv4.devconf_dflt->data[i];
1975 	}
1976 	rcu_read_unlock();
1977 }
1978 
1979 /* called with RTNL locked */
1980 static void inet_forward_change(struct net *net)
1981 {
1982 	struct net_device *dev;
1983 	int on = IPV4_DEVCONF_ALL(net, FORWARDING);
1984 
1985 	IPV4_DEVCONF_ALL(net, ACCEPT_REDIRECTS) = !on;
1986 	IPV4_DEVCONF_DFLT(net, FORWARDING) = on;
1987 	inet_netconf_notify_devconf(net, NETCONFA_FORWARDING,
1988 				    NETCONFA_IFINDEX_ALL,
1989 				    net->ipv4.devconf_all);
1990 	inet_netconf_notify_devconf(net, NETCONFA_FORWARDING,
1991 				    NETCONFA_IFINDEX_DEFAULT,
1992 				    net->ipv4.devconf_dflt);
1993 
1994 	for_each_netdev(net, dev) {
1995 		struct in_device *in_dev;
1996 		if (on)
1997 			dev_disable_lro(dev);
1998 		rcu_read_lock();
1999 		in_dev = __in_dev_get_rcu(dev);
2000 		if (in_dev) {
2001 			IN_DEV_CONF_SET(in_dev, FORWARDING, on);
2002 			inet_netconf_notify_devconf(net, NETCONFA_FORWARDING,
2003 						    dev->ifindex, &in_dev->cnf);
2004 		}
2005 		rcu_read_unlock();
2006 	}
2007 }
2008 
2009 static int devinet_conf_ifindex(struct net *net, struct ipv4_devconf *cnf)
2010 {
2011 	if (cnf == net->ipv4.devconf_dflt)
2012 		return NETCONFA_IFINDEX_DEFAULT;
2013 	else if (cnf == net->ipv4.devconf_all)
2014 		return NETCONFA_IFINDEX_ALL;
2015 	else {
2016 		struct in_device *idev
2017 			= container_of(cnf, struct in_device, cnf);
2018 		return idev->dev->ifindex;
2019 	}
2020 }
2021 
2022 static int devinet_conf_proc(struct ctl_table *ctl, int write,
2023 			     void __user *buffer,
2024 			     size_t *lenp, loff_t *ppos)
2025 {
2026 	int old_value = *(int *)ctl->data;
2027 	int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2028 	int new_value = *(int *)ctl->data;
2029 
2030 	if (write) {
2031 		struct ipv4_devconf *cnf = ctl->extra1;
2032 		struct net *net = ctl->extra2;
2033 		int i = (int *)ctl->data - cnf->data;
2034 		int ifindex;
2035 
2036 		set_bit(i, cnf->state);
2037 
2038 		if (cnf == net->ipv4.devconf_dflt)
2039 			devinet_copy_dflt_conf(net, i);
2040 		if (i == IPV4_DEVCONF_ACCEPT_LOCAL - 1 ||
2041 		    i == IPV4_DEVCONF_ROUTE_LOCALNET - 1)
2042 			if ((new_value == 0) && (old_value != 0))
2043 				rt_cache_flush(net);
2044 
2045 		if (i == IPV4_DEVCONF_RP_FILTER - 1 &&
2046 		    new_value != old_value) {
2047 			ifindex = devinet_conf_ifindex(net, cnf);
2048 			inet_netconf_notify_devconf(net, NETCONFA_RP_FILTER,
2049 						    ifindex, cnf);
2050 		}
2051 		if (i == IPV4_DEVCONF_PROXY_ARP - 1 &&
2052 		    new_value != old_value) {
2053 			ifindex = devinet_conf_ifindex(net, cnf);
2054 			inet_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
2055 						    ifindex, cnf);
2056 		}
2057 		if (i == IPV4_DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN - 1 &&
2058 		    new_value != old_value) {
2059 			ifindex = devinet_conf_ifindex(net, cnf);
2060 			inet_netconf_notify_devconf(net, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
2061 						    ifindex, cnf);
2062 		}
2063 	}
2064 
2065 	return ret;
2066 }
2067 
2068 static int devinet_sysctl_forward(struct ctl_table *ctl, int write,
2069 				  void __user *buffer,
2070 				  size_t *lenp, loff_t *ppos)
2071 {
2072 	int *valp = ctl->data;
2073 	int val = *valp;
2074 	loff_t pos = *ppos;
2075 	int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2076 
2077 	if (write && *valp != val) {
2078 		struct net *net = ctl->extra2;
2079 
2080 		if (valp != &IPV4_DEVCONF_DFLT(net, FORWARDING)) {
2081 			if (!rtnl_trylock()) {
2082 				/* Restore the original values before restarting */
2083 				*valp = val;
2084 				*ppos = pos;
2085 				return restart_syscall();
2086 			}
2087 			if (valp == &IPV4_DEVCONF_ALL(net, FORWARDING)) {
2088 				inet_forward_change(net);
2089 			} else {
2090 				struct ipv4_devconf *cnf = ctl->extra1;
2091 				struct in_device *idev =
2092 					container_of(cnf, struct in_device, cnf);
2093 				if (*valp)
2094 					dev_disable_lro(idev->dev);
2095 				inet_netconf_notify_devconf(net,
2096 							    NETCONFA_FORWARDING,
2097 							    idev->dev->ifindex,
2098 							    cnf);
2099 			}
2100 			rtnl_unlock();
2101 			rt_cache_flush(net);
2102 		} else
2103 			inet_netconf_notify_devconf(net, NETCONFA_FORWARDING,
2104 						    NETCONFA_IFINDEX_DEFAULT,
2105 						    net->ipv4.devconf_dflt);
2106 	}
2107 
2108 	return ret;
2109 }
2110 
2111 static int ipv4_doint_and_flush(struct ctl_table *ctl, int write,
2112 				void __user *buffer,
2113 				size_t *lenp, loff_t *ppos)
2114 {
2115 	int *valp = ctl->data;
2116 	int val = *valp;
2117 	int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2118 	struct net *net = ctl->extra2;
2119 
2120 	if (write && *valp != val)
2121 		rt_cache_flush(net);
2122 
2123 	return ret;
2124 }
2125 
2126 #define DEVINET_SYSCTL_ENTRY(attr, name, mval, proc) \
2127 	{ \
2128 		.procname	= name, \
2129 		.data		= ipv4_devconf.data + \
2130 				  IPV4_DEVCONF_ ## attr - 1, \
2131 		.maxlen		= sizeof(int), \
2132 		.mode		= mval, \
2133 		.proc_handler	= proc, \
2134 		.extra1		= &ipv4_devconf, \
2135 	}
2136 
2137 #define DEVINET_SYSCTL_RW_ENTRY(attr, name) \
2138 	DEVINET_SYSCTL_ENTRY(attr, name, 0644, devinet_conf_proc)
2139 
2140 #define DEVINET_SYSCTL_RO_ENTRY(attr, name) \
2141 	DEVINET_SYSCTL_ENTRY(attr, name, 0444, devinet_conf_proc)
2142 
2143 #define DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, proc) \
2144 	DEVINET_SYSCTL_ENTRY(attr, name, 0644, proc)
2145 
2146 #define DEVINET_SYSCTL_FLUSHING_ENTRY(attr, name) \
2147 	DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, ipv4_doint_and_flush)
2148 
2149 static struct devinet_sysctl_table {
2150 	struct ctl_table_header *sysctl_header;
2151 	struct ctl_table devinet_vars[__IPV4_DEVCONF_MAX];
2152 } devinet_sysctl = {
2153 	.devinet_vars = {
2154 		DEVINET_SYSCTL_COMPLEX_ENTRY(FORWARDING, "forwarding",
2155 					     devinet_sysctl_forward),
2156 		DEVINET_SYSCTL_RO_ENTRY(MC_FORWARDING, "mc_forwarding"),
2157 
2158 		DEVINET_SYSCTL_RW_ENTRY(ACCEPT_REDIRECTS, "accept_redirects"),
2159 		DEVINET_SYSCTL_RW_ENTRY(SECURE_REDIRECTS, "secure_redirects"),
2160 		DEVINET_SYSCTL_RW_ENTRY(SHARED_MEDIA, "shared_media"),
2161 		DEVINET_SYSCTL_RW_ENTRY(RP_FILTER, "rp_filter"),
2162 		DEVINET_SYSCTL_RW_ENTRY(SEND_REDIRECTS, "send_redirects"),
2163 		DEVINET_SYSCTL_RW_ENTRY(ACCEPT_SOURCE_ROUTE,
2164 					"accept_source_route"),
2165 		DEVINET_SYSCTL_RW_ENTRY(ACCEPT_LOCAL, "accept_local"),
2166 		DEVINET_SYSCTL_RW_ENTRY(SRC_VMARK, "src_valid_mark"),
2167 		DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP, "proxy_arp"),
2168 		DEVINET_SYSCTL_RW_ENTRY(MEDIUM_ID, "medium_id"),
2169 		DEVINET_SYSCTL_RW_ENTRY(BOOTP_RELAY, "bootp_relay"),
2170 		DEVINET_SYSCTL_RW_ENTRY(LOG_MARTIANS, "log_martians"),
2171 		DEVINET_SYSCTL_RW_ENTRY(TAG, "tag"),
2172 		DEVINET_SYSCTL_RW_ENTRY(ARPFILTER, "arp_filter"),
2173 		DEVINET_SYSCTL_RW_ENTRY(ARP_ANNOUNCE, "arp_announce"),
2174 		DEVINET_SYSCTL_RW_ENTRY(ARP_IGNORE, "arp_ignore"),
2175 		DEVINET_SYSCTL_RW_ENTRY(ARP_ACCEPT, "arp_accept"),
2176 		DEVINET_SYSCTL_RW_ENTRY(ARP_NOTIFY, "arp_notify"),
2177 		DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP_PVLAN, "proxy_arp_pvlan"),
2178 		DEVINET_SYSCTL_RW_ENTRY(FORCE_IGMP_VERSION,
2179 					"force_igmp_version"),
2180 		DEVINET_SYSCTL_RW_ENTRY(IGMPV2_UNSOLICITED_REPORT_INTERVAL,
2181 					"igmpv2_unsolicited_report_interval"),
2182 		DEVINET_SYSCTL_RW_ENTRY(IGMPV3_UNSOLICITED_REPORT_INTERVAL,
2183 					"igmpv3_unsolicited_report_interval"),
2184 		DEVINET_SYSCTL_RW_ENTRY(IGNORE_ROUTES_WITH_LINKDOWN,
2185 					"ignore_routes_with_linkdown"),
2186 
2187 		DEVINET_SYSCTL_FLUSHING_ENTRY(NOXFRM, "disable_xfrm"),
2188 		DEVINET_SYSCTL_FLUSHING_ENTRY(NOPOLICY, "disable_policy"),
2189 		DEVINET_SYSCTL_FLUSHING_ENTRY(PROMOTE_SECONDARIES,
2190 					      "promote_secondaries"),
2191 		DEVINET_SYSCTL_FLUSHING_ENTRY(ROUTE_LOCALNET,
2192 					      "route_localnet"),
2193 	},
2194 };
2195 
2196 static int __devinet_sysctl_register(struct net *net, char *dev_name,
2197 					struct ipv4_devconf *p)
2198 {
2199 	int i;
2200 	struct devinet_sysctl_table *t;
2201 	char path[sizeof("net/ipv4/conf/") + IFNAMSIZ];
2202 
2203 	t = kmemdup(&devinet_sysctl, sizeof(*t), GFP_KERNEL);
2204 	if (!t)
2205 		goto out;
2206 
2207 	for (i = 0; i < ARRAY_SIZE(t->devinet_vars) - 1; i++) {
2208 		t->devinet_vars[i].data += (char *)p - (char *)&ipv4_devconf;
2209 		t->devinet_vars[i].extra1 = p;
2210 		t->devinet_vars[i].extra2 = net;
2211 	}
2212 
2213 	snprintf(path, sizeof(path), "net/ipv4/conf/%s", dev_name);
2214 
2215 	t->sysctl_header = register_net_sysctl(net, path, t->devinet_vars);
2216 	if (!t->sysctl_header)
2217 		goto free;
2218 
2219 	p->sysctl = t;
2220 	return 0;
2221 
2222 free:
2223 	kfree(t);
2224 out:
2225 	return -ENOBUFS;
2226 }
2227 
2228 static void __devinet_sysctl_unregister(struct ipv4_devconf *cnf)
2229 {
2230 	struct devinet_sysctl_table *t = cnf->sysctl;
2231 
2232 	if (!t)
2233 		return;
2234 
2235 	cnf->sysctl = NULL;
2236 	unregister_net_sysctl_table(t->sysctl_header);
2237 	kfree(t);
2238 }
2239 
2240 static int devinet_sysctl_register(struct in_device *idev)
2241 {
2242 	int err;
2243 
2244 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
2245 		return -EINVAL;
2246 
2247 	err = neigh_sysctl_register(idev->dev, idev->arp_parms, NULL);
2248 	if (err)
2249 		return err;
2250 	err = __devinet_sysctl_register(dev_net(idev->dev), idev->dev->name,
2251 					&idev->cnf);
2252 	if (err)
2253 		neigh_sysctl_unregister(idev->arp_parms);
2254 	return err;
2255 }
2256 
2257 static void devinet_sysctl_unregister(struct in_device *idev)
2258 {
2259 	__devinet_sysctl_unregister(&idev->cnf);
2260 	neigh_sysctl_unregister(idev->arp_parms);
2261 }
2262 
2263 static struct ctl_table ctl_forward_entry[] = {
2264 	{
2265 		.procname	= "ip_forward",
2266 		.data		= &ipv4_devconf.data[
2267 					IPV4_DEVCONF_FORWARDING - 1],
2268 		.maxlen		= sizeof(int),
2269 		.mode		= 0644,
2270 		.proc_handler	= devinet_sysctl_forward,
2271 		.extra1		= &ipv4_devconf,
2272 		.extra2		= &init_net,
2273 	},
2274 	{ },
2275 };
2276 #endif
2277 
2278 static __net_init int devinet_init_net(struct net *net)
2279 {
2280 	int err;
2281 	struct ipv4_devconf *all, *dflt;
2282 #ifdef CONFIG_SYSCTL
2283 	struct ctl_table *tbl = ctl_forward_entry;
2284 	struct ctl_table_header *forw_hdr;
2285 #endif
2286 
2287 	err = -ENOMEM;
2288 	all = &ipv4_devconf;
2289 	dflt = &ipv4_devconf_dflt;
2290 
2291 	if (!net_eq(net, &init_net)) {
2292 		all = kmemdup(all, sizeof(ipv4_devconf), GFP_KERNEL);
2293 		if (!all)
2294 			goto err_alloc_all;
2295 
2296 		dflt = kmemdup(dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL);
2297 		if (!dflt)
2298 			goto err_alloc_dflt;
2299 
2300 #ifdef CONFIG_SYSCTL
2301 		tbl = kmemdup(tbl, sizeof(ctl_forward_entry), GFP_KERNEL);
2302 		if (!tbl)
2303 			goto err_alloc_ctl;
2304 
2305 		tbl[0].data = &all->data[IPV4_DEVCONF_FORWARDING - 1];
2306 		tbl[0].extra1 = all;
2307 		tbl[0].extra2 = net;
2308 #endif
2309 	}
2310 
2311 #ifdef CONFIG_SYSCTL
2312 	err = __devinet_sysctl_register(net, "all", all);
2313 	if (err < 0)
2314 		goto err_reg_all;
2315 
2316 	err = __devinet_sysctl_register(net, "default", dflt);
2317 	if (err < 0)
2318 		goto err_reg_dflt;
2319 
2320 	err = -ENOMEM;
2321 	forw_hdr = register_net_sysctl(net, "net/ipv4", tbl);
2322 	if (!forw_hdr)
2323 		goto err_reg_ctl;
2324 	net->ipv4.forw_hdr = forw_hdr;
2325 #endif
2326 
2327 	net->ipv4.devconf_all = all;
2328 	net->ipv4.devconf_dflt = dflt;
2329 	return 0;
2330 
2331 #ifdef CONFIG_SYSCTL
2332 err_reg_ctl:
2333 	__devinet_sysctl_unregister(dflt);
2334 err_reg_dflt:
2335 	__devinet_sysctl_unregister(all);
2336 err_reg_all:
2337 	if (tbl != ctl_forward_entry)
2338 		kfree(tbl);
2339 err_alloc_ctl:
2340 #endif
2341 	if (dflt != &ipv4_devconf_dflt)
2342 		kfree(dflt);
2343 err_alloc_dflt:
2344 	if (all != &ipv4_devconf)
2345 		kfree(all);
2346 err_alloc_all:
2347 	return err;
2348 }
2349 
2350 static __net_exit void devinet_exit_net(struct net *net)
2351 {
2352 #ifdef CONFIG_SYSCTL
2353 	struct ctl_table *tbl;
2354 
2355 	tbl = net->ipv4.forw_hdr->ctl_table_arg;
2356 	unregister_net_sysctl_table(net->ipv4.forw_hdr);
2357 	__devinet_sysctl_unregister(net->ipv4.devconf_dflt);
2358 	__devinet_sysctl_unregister(net->ipv4.devconf_all);
2359 	kfree(tbl);
2360 #endif
2361 	kfree(net->ipv4.devconf_dflt);
2362 	kfree(net->ipv4.devconf_all);
2363 }
2364 
2365 static __net_initdata struct pernet_operations devinet_ops = {
2366 	.init = devinet_init_net,
2367 	.exit = devinet_exit_net,
2368 };
2369 
2370 static struct rtnl_af_ops inet_af_ops __read_mostly = {
2371 	.family		  = AF_INET,
2372 	.fill_link_af	  = inet_fill_link_af,
2373 	.get_link_af_size = inet_get_link_af_size,
2374 	.validate_link_af = inet_validate_link_af,
2375 	.set_link_af	  = inet_set_link_af,
2376 };
2377 
2378 void __init devinet_init(void)
2379 {
2380 	int i;
2381 
2382 	for (i = 0; i < IN4_ADDR_HSIZE; i++)
2383 		INIT_HLIST_HEAD(&inet_addr_lst[i]);
2384 
2385 	register_pernet_subsys(&devinet_ops);
2386 
2387 	register_gifconf(PF_INET, inet_gifconf);
2388 	register_netdevice_notifier(&ip_netdev_notifier);
2389 
2390 	queue_delayed_work(system_power_efficient_wq, &check_lifetime_work, 0);
2391 
2392 	rtnl_af_register(&inet_af_ops);
2393 
2394 	rtnl_register(PF_INET, RTM_NEWADDR, inet_rtm_newaddr, NULL, NULL);
2395 	rtnl_register(PF_INET, RTM_DELADDR, inet_rtm_deladdr, NULL, NULL);
2396 	rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr, NULL);
2397 	rtnl_register(PF_INET, RTM_GETNETCONF, inet_netconf_get_devconf,
2398 		      inet_netconf_dump_devconf, NULL);
2399 }
2400 
2401