xref: /linux/net/ipv6/addrconf.c (revision 7056741fd9fc14a65608549a4657cf5178f05f63)
1 /*
2  *	IPv6 Address [auto]configuration
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
8  *
9  *	This program is free software; you can redistribute it and/or
10  *      modify it under the terms of the GNU General Public License
11  *      as published by the Free Software Foundation; either version
12  *      2 of the License, or (at your option) any later version.
13  */
14 
15 /*
16  *	Changes:
17  *
18  *	Janos Farkas			:	delete timer on ifdown
19  *	<chexum@bankinf.banki.hu>
20  *	Andi Kleen			:	kill double kfree on module
21  *						unload.
22  *	Maciej W. Rozycki		:	FDDI support
23  *	sekiya@USAGI			:	Don't send too many RS
24  *						packets.
25  *	yoshfuji@USAGI			:       Fixed interval between DAD
26  *						packets.
27  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
28  *						address validation timer.
29  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
30  *						support.
31  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
32  *						address on a same interface.
33  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
34  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
35  *						seq_file.
36  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
37  *						selection; consider scope,
38  *						status etc.
39  */
40 
41 #define pr_fmt(fmt) "IPv6: " fmt
42 
43 #include <linux/errno.h>
44 #include <linux/types.h>
45 #include <linux/kernel.h>
46 #include <linux/socket.h>
47 #include <linux/sockios.h>
48 #include <linux/net.h>
49 #include <linux/in6.h>
50 #include <linux/netdevice.h>
51 #include <linux/if_addr.h>
52 #include <linux/if_arp.h>
53 #include <linux/if_arcnet.h>
54 #include <linux/if_infiniband.h>
55 #include <linux/route.h>
56 #include <linux/inetdevice.h>
57 #include <linux/init.h>
58 #include <linux/slab.h>
59 #ifdef CONFIG_SYSCTL
60 #include <linux/sysctl.h>
61 #endif
62 #include <linux/capability.h>
63 #include <linux/delay.h>
64 #include <linux/notifier.h>
65 #include <linux/string.h>
66 #include <linux/hash.h>
67 
68 #include <net/net_namespace.h>
69 #include <net/sock.h>
70 #include <net/snmp.h>
71 
72 #include <net/af_ieee802154.h>
73 #include <net/ipv6.h>
74 #include <net/protocol.h>
75 #include <net/ndisc.h>
76 #include <net/ip6_route.h>
77 #include <net/addrconf.h>
78 #include <net/tcp.h>
79 #include <net/ip.h>
80 #include <net/netlink.h>
81 #include <net/pkt_sched.h>
82 #include <linux/if_tunnel.h>
83 #include <linux/rtnetlink.h>
84 
85 #ifdef CONFIG_IPV6_PRIVACY
86 #include <linux/random.h>
87 #endif
88 
89 #include <linux/uaccess.h>
90 #include <asm/unaligned.h>
91 
92 #include <linux/proc_fs.h>
93 #include <linux/seq_file.h>
94 #include <linux/export.h>
95 
96 /* Set to 3 to get tracing... */
97 #define ACONF_DEBUG 2
98 
99 #if ACONF_DEBUG >= 3
100 #define ADBG(x) printk x
101 #else
102 #define ADBG(x)
103 #endif
104 
105 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
106 
107 static inline u32 cstamp_delta(unsigned long cstamp)
108 {
109 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
110 }
111 
112 #define ADDRCONF_TIMER_FUZZ_MINUS	(HZ > 50 ? HZ/50 : 1)
113 #define ADDRCONF_TIMER_FUZZ		(HZ / 4)
114 #define ADDRCONF_TIMER_FUZZ_MAX		(HZ)
115 
116 #ifdef CONFIG_SYSCTL
117 static void addrconf_sysctl_register(struct inet6_dev *idev);
118 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
119 #else
120 static inline void addrconf_sysctl_register(struct inet6_dev *idev)
121 {
122 }
123 
124 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
125 {
126 }
127 #endif
128 
129 #ifdef CONFIG_IPV6_PRIVACY
130 static void __ipv6_regen_rndid(struct inet6_dev *idev);
131 static void __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
132 static void ipv6_regen_rndid(unsigned long data);
133 #endif
134 
135 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
136 static int ipv6_count_addresses(struct inet6_dev *idev);
137 
138 /*
139  *	Configured unicast address hash table
140  */
141 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
142 static DEFINE_SPINLOCK(addrconf_hash_lock);
143 
144 static void addrconf_verify(unsigned long);
145 
146 static DEFINE_TIMER(addr_chk_timer, addrconf_verify, 0, 0);
147 static DEFINE_SPINLOCK(addrconf_verify_lock);
148 
149 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
150 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
151 
152 static void addrconf_type_change(struct net_device *dev,
153 				 unsigned long event);
154 static int addrconf_ifdown(struct net_device *dev, int how);
155 
156 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
157 static void addrconf_dad_timer(unsigned long data);
158 static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
159 static void addrconf_dad_run(struct inet6_dev *idev);
160 static void addrconf_rs_timer(unsigned long data);
161 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
162 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
163 
164 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
165 				struct prefix_info *pinfo);
166 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
167 			       struct net_device *dev);
168 
169 static ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
170 
171 static struct ipv6_devconf ipv6_devconf __read_mostly = {
172 	.forwarding		= 0,
173 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
174 	.mtu6			= IPV6_MIN_MTU,
175 	.accept_ra		= 1,
176 	.accept_redirects	= 1,
177 	.autoconf		= 1,
178 	.force_mld_version	= 0,
179 	.dad_transmits		= 1,
180 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
181 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
182 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
183 #ifdef CONFIG_IPV6_PRIVACY
184 	.use_tempaddr 		= 0,
185 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
186 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
187 	.regen_max_retry	= REGEN_MAX_RETRY,
188 	.max_desync_factor	= MAX_DESYNC_FACTOR,
189 #endif
190 	.max_addresses		= IPV6_MAX_ADDRESSES,
191 	.accept_ra_defrtr	= 1,
192 	.accept_ra_pinfo	= 1,
193 #ifdef CONFIG_IPV6_ROUTER_PREF
194 	.accept_ra_rtr_pref	= 1,
195 	.rtr_probe_interval	= 60 * HZ,
196 #ifdef CONFIG_IPV6_ROUTE_INFO
197 	.accept_ra_rt_info_max_plen = 0,
198 #endif
199 #endif
200 	.proxy_ndp		= 0,
201 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
202 	.disable_ipv6		= 0,
203 	.accept_dad		= 1,
204 };
205 
206 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
207 	.forwarding		= 0,
208 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
209 	.mtu6			= IPV6_MIN_MTU,
210 	.accept_ra		= 1,
211 	.accept_redirects	= 1,
212 	.autoconf		= 1,
213 	.dad_transmits		= 1,
214 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
215 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
216 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
217 #ifdef CONFIG_IPV6_PRIVACY
218 	.use_tempaddr		= 0,
219 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
220 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
221 	.regen_max_retry	= REGEN_MAX_RETRY,
222 	.max_desync_factor	= MAX_DESYNC_FACTOR,
223 #endif
224 	.max_addresses		= IPV6_MAX_ADDRESSES,
225 	.accept_ra_defrtr	= 1,
226 	.accept_ra_pinfo	= 1,
227 #ifdef CONFIG_IPV6_ROUTER_PREF
228 	.accept_ra_rtr_pref	= 1,
229 	.rtr_probe_interval	= 60 * HZ,
230 #ifdef CONFIG_IPV6_ROUTE_INFO
231 	.accept_ra_rt_info_max_plen = 0,
232 #endif
233 #endif
234 	.proxy_ndp		= 0,
235 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
236 	.disable_ipv6		= 0,
237 	.accept_dad		= 1,
238 };
239 
240 /* IPv6 Wildcard Address and Loopback Address defined by RFC2553 */
241 const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
242 const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
243 const struct in6_addr in6addr_linklocal_allnodes = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
244 const struct in6_addr in6addr_linklocal_allrouters = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
245 
246 /* Check if a valid qdisc is available */
247 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
248 {
249 	return !qdisc_tx_is_noop(dev);
250 }
251 
252 /* Check if a route is valid prefix route */
253 static inline int addrconf_is_prefix_route(const struct rt6_info *rt)
254 {
255 	return (rt->rt6i_flags & (RTF_GATEWAY | RTF_DEFAULT)) == 0;
256 }
257 
258 static void addrconf_del_timer(struct inet6_ifaddr *ifp)
259 {
260 	if (del_timer(&ifp->timer))
261 		__in6_ifa_put(ifp);
262 }
263 
264 enum addrconf_timer_t {
265 	AC_NONE,
266 	AC_DAD,
267 	AC_RS,
268 };
269 
270 static void addrconf_mod_timer(struct inet6_ifaddr *ifp,
271 			       enum addrconf_timer_t what,
272 			       unsigned long when)
273 {
274 	if (!del_timer(&ifp->timer))
275 		in6_ifa_hold(ifp);
276 
277 	switch (what) {
278 	case AC_DAD:
279 		ifp->timer.function = addrconf_dad_timer;
280 		break;
281 	case AC_RS:
282 		ifp->timer.function = addrconf_rs_timer;
283 		break;
284 	default:
285 		break;
286 	}
287 	ifp->timer.expires = jiffies + when;
288 	add_timer(&ifp->timer);
289 }
290 
291 static int snmp6_alloc_dev(struct inet6_dev *idev)
292 {
293 	if (snmp_mib_init((void __percpu **)idev->stats.ipv6,
294 			  sizeof(struct ipstats_mib),
295 			  __alignof__(struct ipstats_mib)) < 0)
296 		goto err_ip;
297 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
298 					GFP_KERNEL);
299 	if (!idev->stats.icmpv6dev)
300 		goto err_icmp;
301 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
302 					   GFP_KERNEL);
303 	if (!idev->stats.icmpv6msgdev)
304 		goto err_icmpmsg;
305 
306 	return 0;
307 
308 err_icmpmsg:
309 	kfree(idev->stats.icmpv6dev);
310 err_icmp:
311 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
312 err_ip:
313 	return -ENOMEM;
314 }
315 
316 static void snmp6_free_dev(struct inet6_dev *idev)
317 {
318 	kfree(idev->stats.icmpv6msgdev);
319 	kfree(idev->stats.icmpv6dev);
320 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
321 }
322 
323 /* Nobody refers to this device, we may destroy it. */
324 
325 void in6_dev_finish_destroy(struct inet6_dev *idev)
326 {
327 	struct net_device *dev = idev->dev;
328 
329 	WARN_ON(!list_empty(&idev->addr_list));
330 	WARN_ON(idev->mc_list != NULL);
331 
332 #ifdef NET_REFCNT_DEBUG
333 	pr_debug("%s: %s\n", __func__, dev ? dev->name : "NIL");
334 #endif
335 	dev_put(dev);
336 	if (!idev->dead) {
337 		pr_warn("Freeing alive inet6 device %p\n", idev);
338 		return;
339 	}
340 	snmp6_free_dev(idev);
341 	kfree_rcu(idev, rcu);
342 }
343 EXPORT_SYMBOL(in6_dev_finish_destroy);
344 
345 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
346 {
347 	struct inet6_dev *ndev;
348 
349 	ASSERT_RTNL();
350 
351 	if (dev->mtu < IPV6_MIN_MTU)
352 		return NULL;
353 
354 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
355 
356 	if (ndev == NULL)
357 		return NULL;
358 
359 	rwlock_init(&ndev->lock);
360 	ndev->dev = dev;
361 	INIT_LIST_HEAD(&ndev->addr_list);
362 
363 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
364 	ndev->cnf.mtu6 = dev->mtu;
365 	ndev->cnf.sysctl = NULL;
366 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
367 	if (ndev->nd_parms == NULL) {
368 		kfree(ndev);
369 		return NULL;
370 	}
371 	if (ndev->cnf.forwarding)
372 		dev_disable_lro(dev);
373 	/* We refer to the device */
374 	dev_hold(dev);
375 
376 	if (snmp6_alloc_dev(ndev) < 0) {
377 		ADBG((KERN_WARNING
378 			"%s: cannot allocate memory for statistics; dev=%s.\n",
379 			__func__, dev->name));
380 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
381 		dev_put(dev);
382 		kfree(ndev);
383 		return NULL;
384 	}
385 
386 	if (snmp6_register_dev(ndev) < 0) {
387 		ADBG((KERN_WARNING
388 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
389 			__func__, dev->name));
390 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
391 		ndev->dead = 1;
392 		in6_dev_finish_destroy(ndev);
393 		return NULL;
394 	}
395 
396 	/* One reference from device.  We must do this before
397 	 * we invoke __ipv6_regen_rndid().
398 	 */
399 	in6_dev_hold(ndev);
400 
401 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
402 		ndev->cnf.accept_dad = -1;
403 
404 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
405 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
406 		pr_info("%s: Disabled Multicast RS\n", dev->name);
407 		ndev->cnf.rtr_solicits = 0;
408 	}
409 #endif
410 
411 #ifdef CONFIG_IPV6_PRIVACY
412 	INIT_LIST_HEAD(&ndev->tempaddr_list);
413 	setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
414 	if ((dev->flags&IFF_LOOPBACK) ||
415 	    dev->type == ARPHRD_TUNNEL ||
416 	    dev->type == ARPHRD_TUNNEL6 ||
417 	    dev->type == ARPHRD_SIT ||
418 	    dev->type == ARPHRD_NONE) {
419 		ndev->cnf.use_tempaddr = -1;
420 	} else {
421 		in6_dev_hold(ndev);
422 		ipv6_regen_rndid((unsigned long) ndev);
423 	}
424 #endif
425 
426 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
427 		ndev->if_flags |= IF_READY;
428 
429 	ipv6_mc_init_dev(ndev);
430 	ndev->tstamp = jiffies;
431 	addrconf_sysctl_register(ndev);
432 	/* protected by rtnl_lock */
433 	rcu_assign_pointer(dev->ip6_ptr, ndev);
434 
435 	/* Join all-node multicast group */
436 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
437 
438 	/* Join all-router multicast group if forwarding is set */
439 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
440 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
441 
442 	return ndev;
443 }
444 
445 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
446 {
447 	struct inet6_dev *idev;
448 
449 	ASSERT_RTNL();
450 
451 	idev = __in6_dev_get(dev);
452 	if (!idev) {
453 		idev = ipv6_add_dev(dev);
454 		if (!idev)
455 			return NULL;
456 	}
457 
458 	if (dev->flags&IFF_UP)
459 		ipv6_mc_up(idev);
460 	return idev;
461 }
462 
463 #ifdef CONFIG_SYSCTL
464 static void dev_forward_change(struct inet6_dev *idev)
465 {
466 	struct net_device *dev;
467 	struct inet6_ifaddr *ifa;
468 
469 	if (!idev)
470 		return;
471 	dev = idev->dev;
472 	if (idev->cnf.forwarding)
473 		dev_disable_lro(dev);
474 	if (dev && (dev->flags & IFF_MULTICAST)) {
475 		if (idev->cnf.forwarding)
476 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
477 		else
478 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
479 	}
480 
481 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
482 		if (ifa->flags&IFA_F_TENTATIVE)
483 			continue;
484 		if (idev->cnf.forwarding)
485 			addrconf_join_anycast(ifa);
486 		else
487 			addrconf_leave_anycast(ifa);
488 	}
489 }
490 
491 
492 static void addrconf_forward_change(struct net *net, __s32 newf)
493 {
494 	struct net_device *dev;
495 	struct inet6_dev *idev;
496 
497 	for_each_netdev(net, dev) {
498 		idev = __in6_dev_get(dev);
499 		if (idev) {
500 			int changed = (!idev->cnf.forwarding) ^ (!newf);
501 			idev->cnf.forwarding = newf;
502 			if (changed)
503 				dev_forward_change(idev);
504 		}
505 	}
506 }
507 
508 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
509 {
510 	struct net *net;
511 	int old;
512 
513 	if (!rtnl_trylock())
514 		return restart_syscall();
515 
516 	net = (struct net *)table->extra2;
517 	old = *p;
518 	*p = newf;
519 
520 	if (p == &net->ipv6.devconf_dflt->forwarding) {
521 		rtnl_unlock();
522 		return 0;
523 	}
524 
525 	if (p == &net->ipv6.devconf_all->forwarding) {
526 		net->ipv6.devconf_dflt->forwarding = newf;
527 		addrconf_forward_change(net, newf);
528 	} else if ((!newf) ^ (!old))
529 		dev_forward_change((struct inet6_dev *)table->extra1);
530 	rtnl_unlock();
531 
532 	if (newf)
533 		rt6_purge_dflt_routers(net);
534 	return 1;
535 }
536 #endif
537 
538 /* Nobody refers to this ifaddr, destroy it */
539 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
540 {
541 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
542 
543 #ifdef NET_REFCNT_DEBUG
544 	pr_debug("%s\n", __func__);
545 #endif
546 
547 	in6_dev_put(ifp->idev);
548 
549 	if (del_timer(&ifp->timer))
550 		pr_notice("Timer is still running, when freeing ifa=%p\n", ifp);
551 
552 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
553 		pr_warn("Freeing alive inet6 address %p\n", ifp);
554 		return;
555 	}
556 	dst_release(&ifp->rt->dst);
557 
558 	kfree_rcu(ifp, rcu);
559 }
560 
561 static void
562 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
563 {
564 	struct list_head *p;
565 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
566 
567 	/*
568 	 * Each device address list is sorted in order of scope -
569 	 * global before linklocal.
570 	 */
571 	list_for_each(p, &idev->addr_list) {
572 		struct inet6_ifaddr *ifa
573 			= list_entry(p, struct inet6_ifaddr, if_list);
574 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
575 			break;
576 	}
577 
578 	list_add_tail(&ifp->if_list, p);
579 }
580 
581 static u32 inet6_addr_hash(const struct in6_addr *addr)
582 {
583 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
584 }
585 
586 /* On success it returns ifp with increased reference count */
587 
588 static struct inet6_ifaddr *
589 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen,
590 	      int scope, u32 flags)
591 {
592 	struct inet6_ifaddr *ifa = NULL;
593 	struct rt6_info *rt;
594 	unsigned int hash;
595 	int err = 0;
596 	int addr_type = ipv6_addr_type(addr);
597 
598 	if (addr_type == IPV6_ADDR_ANY ||
599 	    addr_type & IPV6_ADDR_MULTICAST ||
600 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
601 	     addr_type & IPV6_ADDR_LOOPBACK))
602 		return ERR_PTR(-EADDRNOTAVAIL);
603 
604 	rcu_read_lock_bh();
605 	if (idev->dead) {
606 		err = -ENODEV;			/*XXX*/
607 		goto out2;
608 	}
609 
610 	if (idev->cnf.disable_ipv6) {
611 		err = -EACCES;
612 		goto out2;
613 	}
614 
615 	spin_lock(&addrconf_hash_lock);
616 
617 	/* Ignore adding duplicate addresses on an interface */
618 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
619 		ADBG(("ipv6_add_addr: already assigned\n"));
620 		err = -EEXIST;
621 		goto out;
622 	}
623 
624 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
625 
626 	if (ifa == NULL) {
627 		ADBG(("ipv6_add_addr: malloc failed\n"));
628 		err = -ENOBUFS;
629 		goto out;
630 	}
631 
632 	rt = addrconf_dst_alloc(idev, addr, false);
633 	if (IS_ERR(rt)) {
634 		err = PTR_ERR(rt);
635 		goto out;
636 	}
637 
638 	ifa->addr = *addr;
639 
640 	spin_lock_init(&ifa->lock);
641 	spin_lock_init(&ifa->state_lock);
642 	init_timer(&ifa->timer);
643 	INIT_HLIST_NODE(&ifa->addr_lst);
644 	ifa->timer.data = (unsigned long) ifa;
645 	ifa->scope = scope;
646 	ifa->prefix_len = pfxlen;
647 	ifa->flags = flags | IFA_F_TENTATIVE;
648 	ifa->cstamp = ifa->tstamp = jiffies;
649 
650 	ifa->rt = rt;
651 
652 	ifa->idev = idev;
653 	in6_dev_hold(idev);
654 	/* For caller */
655 	in6_ifa_hold(ifa);
656 
657 	/* Add to big hash table */
658 	hash = inet6_addr_hash(addr);
659 
660 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
661 	spin_unlock(&addrconf_hash_lock);
662 
663 	write_lock(&idev->lock);
664 	/* Add to inet6_dev unicast addr list. */
665 	ipv6_link_dev_addr(idev, ifa);
666 
667 #ifdef CONFIG_IPV6_PRIVACY
668 	if (ifa->flags&IFA_F_TEMPORARY) {
669 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
670 		in6_ifa_hold(ifa);
671 	}
672 #endif
673 
674 	in6_ifa_hold(ifa);
675 	write_unlock(&idev->lock);
676 out2:
677 	rcu_read_unlock_bh();
678 
679 	if (likely(err == 0))
680 		atomic_notifier_call_chain(&inet6addr_chain, NETDEV_UP, ifa);
681 	else {
682 		kfree(ifa);
683 		ifa = ERR_PTR(err);
684 	}
685 
686 	return ifa;
687 out:
688 	spin_unlock(&addrconf_hash_lock);
689 	goto out2;
690 }
691 
692 /* This function wants to get referenced ifp and releases it before return */
693 
694 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
695 {
696 	struct inet6_ifaddr *ifa, *ifn;
697 	struct inet6_dev *idev = ifp->idev;
698 	int state;
699 	int deleted = 0, onlink = 0;
700 	unsigned long expires = jiffies;
701 
702 	spin_lock_bh(&ifp->state_lock);
703 	state = ifp->state;
704 	ifp->state = INET6_IFADDR_STATE_DEAD;
705 	spin_unlock_bh(&ifp->state_lock);
706 
707 	if (state == INET6_IFADDR_STATE_DEAD)
708 		goto out;
709 
710 	spin_lock_bh(&addrconf_hash_lock);
711 	hlist_del_init_rcu(&ifp->addr_lst);
712 	spin_unlock_bh(&addrconf_hash_lock);
713 
714 	write_lock_bh(&idev->lock);
715 #ifdef CONFIG_IPV6_PRIVACY
716 	if (ifp->flags&IFA_F_TEMPORARY) {
717 		list_del(&ifp->tmp_list);
718 		if (ifp->ifpub) {
719 			in6_ifa_put(ifp->ifpub);
720 			ifp->ifpub = NULL;
721 		}
722 		__in6_ifa_put(ifp);
723 	}
724 #endif
725 
726 	list_for_each_entry_safe(ifa, ifn, &idev->addr_list, if_list) {
727 		if (ifa == ifp) {
728 			list_del_init(&ifp->if_list);
729 			__in6_ifa_put(ifp);
730 
731 			if (!(ifp->flags & IFA_F_PERMANENT) || onlink > 0)
732 				break;
733 			deleted = 1;
734 			continue;
735 		} else if (ifp->flags & IFA_F_PERMANENT) {
736 			if (ipv6_prefix_equal(&ifa->addr, &ifp->addr,
737 					      ifp->prefix_len)) {
738 				if (ifa->flags & IFA_F_PERMANENT) {
739 					onlink = 1;
740 					if (deleted)
741 						break;
742 				} else {
743 					unsigned long lifetime;
744 
745 					if (!onlink)
746 						onlink = -1;
747 
748 					spin_lock(&ifa->lock);
749 
750 					lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
751 					/*
752 					 * Note: Because this address is
753 					 * not permanent, lifetime <
754 					 * LONG_MAX / HZ here.
755 					 */
756 					if (time_before(expires,
757 							ifa->tstamp + lifetime * HZ))
758 						expires = ifa->tstamp + lifetime * HZ;
759 					spin_unlock(&ifa->lock);
760 				}
761 			}
762 		}
763 	}
764 	write_unlock_bh(&idev->lock);
765 
766 	addrconf_del_timer(ifp);
767 
768 	ipv6_ifa_notify(RTM_DELADDR, ifp);
769 
770 	atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifp);
771 
772 	/*
773 	 * Purge or update corresponding prefix
774 	 *
775 	 * 1) we don't purge prefix here if address was not permanent.
776 	 *    prefix is managed by its own lifetime.
777 	 * 2) if there're no addresses, delete prefix.
778 	 * 3) if there're still other permanent address(es),
779 	 *    corresponding prefix is still permanent.
780 	 * 4) otherwise, update prefix lifetime to the
781 	 *    longest valid lifetime among the corresponding
782 	 *    addresses on the device.
783 	 *    Note: subsequent RA will update lifetime.
784 	 *
785 	 * --yoshfuji
786 	 */
787 	if ((ifp->flags & IFA_F_PERMANENT) && onlink < 1) {
788 		struct in6_addr prefix;
789 		struct rt6_info *rt;
790 		struct net *net = dev_net(ifp->idev->dev);
791 		struct flowi6 fl6 = {};
792 
793 		ipv6_addr_prefix(&prefix, &ifp->addr, ifp->prefix_len);
794 		fl6.flowi6_oif = ifp->idev->dev->ifindex;
795 		fl6.daddr = prefix;
796 		rt = (struct rt6_info *)ip6_route_lookup(net, &fl6,
797 							 RT6_LOOKUP_F_IFACE);
798 
799 		if (rt != net->ipv6.ip6_null_entry &&
800 		    addrconf_is_prefix_route(rt)) {
801 			if (onlink == 0) {
802 				ip6_del_rt(rt);
803 				rt = NULL;
804 			} else if (!(rt->rt6i_flags & RTF_EXPIRES)) {
805 				rt6_set_expires(rt, expires);
806 			}
807 		}
808 		dst_release(&rt->dst);
809 	}
810 
811 	/* clean up prefsrc entries */
812 	rt6_remove_prefsrc(ifp);
813 out:
814 	in6_ifa_put(ifp);
815 }
816 
817 #ifdef CONFIG_IPV6_PRIVACY
818 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
819 {
820 	struct inet6_dev *idev = ifp->idev;
821 	struct in6_addr addr, *tmpaddr;
822 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
823 	unsigned long regen_advance;
824 	int tmp_plen;
825 	int ret = 0;
826 	int max_addresses;
827 	u32 addr_flags;
828 	unsigned long now = jiffies;
829 
830 	write_lock(&idev->lock);
831 	if (ift) {
832 		spin_lock_bh(&ift->lock);
833 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
834 		spin_unlock_bh(&ift->lock);
835 		tmpaddr = &addr;
836 	} else {
837 		tmpaddr = NULL;
838 	}
839 retry:
840 	in6_dev_hold(idev);
841 	if (idev->cnf.use_tempaddr <= 0) {
842 		write_unlock(&idev->lock);
843 		pr_info("%s: use_tempaddr is disabled\n", __func__);
844 		in6_dev_put(idev);
845 		ret = -1;
846 		goto out;
847 	}
848 	spin_lock_bh(&ifp->lock);
849 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
850 		idev->cnf.use_tempaddr = -1;	/*XXX*/
851 		spin_unlock_bh(&ifp->lock);
852 		write_unlock(&idev->lock);
853 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
854 			__func__);
855 		in6_dev_put(idev);
856 		ret = -1;
857 		goto out;
858 	}
859 	in6_ifa_hold(ifp);
860 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
861 	__ipv6_try_regen_rndid(idev, tmpaddr);
862 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
863 	age = (now - ifp->tstamp) / HZ;
864 	tmp_valid_lft = min_t(__u32,
865 			      ifp->valid_lft,
866 			      idev->cnf.temp_valid_lft + age);
867 	tmp_prefered_lft = min_t(__u32,
868 				 ifp->prefered_lft,
869 				 idev->cnf.temp_prefered_lft + age -
870 				 idev->cnf.max_desync_factor);
871 	tmp_plen = ifp->prefix_len;
872 	max_addresses = idev->cnf.max_addresses;
873 	tmp_tstamp = ifp->tstamp;
874 	spin_unlock_bh(&ifp->lock);
875 
876 	regen_advance = idev->cnf.regen_max_retry *
877 	                idev->cnf.dad_transmits *
878 	                idev->nd_parms->retrans_time / HZ;
879 	write_unlock(&idev->lock);
880 
881 	/* A temporary address is created only if this calculated Preferred
882 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
883 	 * an implementation must not create a temporary address with a zero
884 	 * Preferred Lifetime.
885 	 */
886 	if (tmp_prefered_lft <= regen_advance) {
887 		in6_ifa_put(ifp);
888 		in6_dev_put(idev);
889 		ret = -1;
890 		goto out;
891 	}
892 
893 	addr_flags = IFA_F_TEMPORARY;
894 	/* set in addrconf_prefix_rcv() */
895 	if (ifp->flags & IFA_F_OPTIMISTIC)
896 		addr_flags |= IFA_F_OPTIMISTIC;
897 
898 	ift = !max_addresses ||
899 	      ipv6_count_addresses(idev) < max_addresses ?
900 		ipv6_add_addr(idev, &addr, tmp_plen,
901 			      ipv6_addr_type(&addr)&IPV6_ADDR_SCOPE_MASK,
902 			      addr_flags) : NULL;
903 	if (!ift || IS_ERR(ift)) {
904 		in6_ifa_put(ifp);
905 		in6_dev_put(idev);
906 		pr_info("%s: retry temporary address regeneration\n", __func__);
907 		tmpaddr = &addr;
908 		write_lock(&idev->lock);
909 		goto retry;
910 	}
911 
912 	spin_lock_bh(&ift->lock);
913 	ift->ifpub = ifp;
914 	ift->valid_lft = tmp_valid_lft;
915 	ift->prefered_lft = tmp_prefered_lft;
916 	ift->cstamp = now;
917 	ift->tstamp = tmp_tstamp;
918 	spin_unlock_bh(&ift->lock);
919 
920 	addrconf_dad_start(ift);
921 	in6_ifa_put(ift);
922 	in6_dev_put(idev);
923 out:
924 	return ret;
925 }
926 #endif
927 
928 /*
929  *	Choose an appropriate source address (RFC3484)
930  */
931 enum {
932 	IPV6_SADDR_RULE_INIT = 0,
933 	IPV6_SADDR_RULE_LOCAL,
934 	IPV6_SADDR_RULE_SCOPE,
935 	IPV6_SADDR_RULE_PREFERRED,
936 #ifdef CONFIG_IPV6_MIP6
937 	IPV6_SADDR_RULE_HOA,
938 #endif
939 	IPV6_SADDR_RULE_OIF,
940 	IPV6_SADDR_RULE_LABEL,
941 #ifdef CONFIG_IPV6_PRIVACY
942 	IPV6_SADDR_RULE_PRIVACY,
943 #endif
944 	IPV6_SADDR_RULE_ORCHID,
945 	IPV6_SADDR_RULE_PREFIX,
946 	IPV6_SADDR_RULE_MAX
947 };
948 
949 struct ipv6_saddr_score {
950 	int			rule;
951 	int			addr_type;
952 	struct inet6_ifaddr	*ifa;
953 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
954 	int			scopedist;
955 	int			matchlen;
956 };
957 
958 struct ipv6_saddr_dst {
959 	const struct in6_addr *addr;
960 	int ifindex;
961 	int scope;
962 	int label;
963 	unsigned int prefs;
964 };
965 
966 static inline int ipv6_saddr_preferred(int type)
967 {
968 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
969 		return 1;
970 	return 0;
971 }
972 
973 static int ipv6_get_saddr_eval(struct net *net,
974 			       struct ipv6_saddr_score *score,
975 			       struct ipv6_saddr_dst *dst,
976 			       int i)
977 {
978 	int ret;
979 
980 	if (i <= score->rule) {
981 		switch (i) {
982 		case IPV6_SADDR_RULE_SCOPE:
983 			ret = score->scopedist;
984 			break;
985 		case IPV6_SADDR_RULE_PREFIX:
986 			ret = score->matchlen;
987 			break;
988 		default:
989 			ret = !!test_bit(i, score->scorebits);
990 		}
991 		goto out;
992 	}
993 
994 	switch (i) {
995 	case IPV6_SADDR_RULE_INIT:
996 		/* Rule 0: remember if hiscore is not ready yet */
997 		ret = !!score->ifa;
998 		break;
999 	case IPV6_SADDR_RULE_LOCAL:
1000 		/* Rule 1: Prefer same address */
1001 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1002 		break;
1003 	case IPV6_SADDR_RULE_SCOPE:
1004 		/* Rule 2: Prefer appropriate scope
1005 		 *
1006 		 *      ret
1007 		 *       ^
1008 		 *    -1 |  d 15
1009 		 *    ---+--+-+---> scope
1010 		 *       |
1011 		 *       |             d is scope of the destination.
1012 		 *  B-d  |  \
1013 		 *       |   \      <- smaller scope is better if
1014 		 *  B-15 |    \        if scope is enough for destinaion.
1015 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1016 		 * d-C-1 | /
1017 		 *       |/         <- greater is better
1018 		 *   -C  /             if scope is not enough for destination.
1019 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1020 		 *
1021 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1022 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1023 		 * Assume B = 0 and we get C > 29.
1024 		 */
1025 		ret = __ipv6_addr_src_scope(score->addr_type);
1026 		if (ret >= dst->scope)
1027 			ret = -ret;
1028 		else
1029 			ret -= 128;	/* 30 is enough */
1030 		score->scopedist = ret;
1031 		break;
1032 	case IPV6_SADDR_RULE_PREFERRED:
1033 		/* Rule 3: Avoid deprecated and optimistic addresses */
1034 		ret = ipv6_saddr_preferred(score->addr_type) ||
1035 		      !(score->ifa->flags & (IFA_F_DEPRECATED|IFA_F_OPTIMISTIC));
1036 		break;
1037 #ifdef CONFIG_IPV6_MIP6
1038 	case IPV6_SADDR_RULE_HOA:
1039 	    {
1040 		/* Rule 4: Prefer home address */
1041 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1042 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1043 		break;
1044 	    }
1045 #endif
1046 	case IPV6_SADDR_RULE_OIF:
1047 		/* Rule 5: Prefer outgoing interface */
1048 		ret = (!dst->ifindex ||
1049 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1050 		break;
1051 	case IPV6_SADDR_RULE_LABEL:
1052 		/* Rule 6: Prefer matching label */
1053 		ret = ipv6_addr_label(net,
1054 				      &score->ifa->addr, score->addr_type,
1055 				      score->ifa->idev->dev->ifindex) == dst->label;
1056 		break;
1057 #ifdef CONFIG_IPV6_PRIVACY
1058 	case IPV6_SADDR_RULE_PRIVACY:
1059 	    {
1060 		/* Rule 7: Prefer public address
1061 		 * Note: prefer temporary address if use_tempaddr >= 2
1062 		 */
1063 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1064 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1065 				score->ifa->idev->cnf.use_tempaddr >= 2;
1066 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1067 		break;
1068 	    }
1069 #endif
1070 	case IPV6_SADDR_RULE_ORCHID:
1071 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1072 		 *	    non-ORCHID vs non-ORCHID
1073 		 */
1074 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1075 			ipv6_addr_orchid(dst->addr));
1076 		break;
1077 	case IPV6_SADDR_RULE_PREFIX:
1078 		/* Rule 8: Use longest matching prefix */
1079 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1080 		if (ret > score->ifa->prefix_len)
1081 			ret = score->ifa->prefix_len;
1082 		score->matchlen = ret;
1083 		break;
1084 	default:
1085 		ret = 0;
1086 	}
1087 
1088 	if (ret)
1089 		__set_bit(i, score->scorebits);
1090 	score->rule = i;
1091 out:
1092 	return ret;
1093 }
1094 
1095 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1096 		       const struct in6_addr *daddr, unsigned int prefs,
1097 		       struct in6_addr *saddr)
1098 {
1099 	struct ipv6_saddr_score scores[2],
1100 				*score = &scores[0], *hiscore = &scores[1];
1101 	struct ipv6_saddr_dst dst;
1102 	struct net_device *dev;
1103 	int dst_type;
1104 
1105 	dst_type = __ipv6_addr_type(daddr);
1106 	dst.addr = daddr;
1107 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1108 	dst.scope = __ipv6_addr_src_scope(dst_type);
1109 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1110 	dst.prefs = prefs;
1111 
1112 	hiscore->rule = -1;
1113 	hiscore->ifa = NULL;
1114 
1115 	rcu_read_lock();
1116 
1117 	for_each_netdev_rcu(net, dev) {
1118 		struct inet6_dev *idev;
1119 
1120 		/* Candidate Source Address (section 4)
1121 		 *  - multicast and link-local destination address,
1122 		 *    the set of candidate source address MUST only
1123 		 *    include addresses assigned to interfaces
1124 		 *    belonging to the same link as the outgoing
1125 		 *    interface.
1126 		 * (- For site-local destination addresses, the
1127 		 *    set of candidate source addresses MUST only
1128 		 *    include addresses assigned to interfaces
1129 		 *    belonging to the same site as the outgoing
1130 		 *    interface.)
1131 		 */
1132 		if (((dst_type & IPV6_ADDR_MULTICAST) ||
1133 		     dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) &&
1134 		    dst.ifindex && dev->ifindex != dst.ifindex)
1135 			continue;
1136 
1137 		idev = __in6_dev_get(dev);
1138 		if (!idev)
1139 			continue;
1140 
1141 		read_lock_bh(&idev->lock);
1142 		list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1143 			int i;
1144 
1145 			/*
1146 			 * - Tentative Address (RFC2462 section 5.4)
1147 			 *  - A tentative address is not considered
1148 			 *    "assigned to an interface" in the traditional
1149 			 *    sense, unless it is also flagged as optimistic.
1150 			 * - Candidate Source Address (section 4)
1151 			 *  - In any case, anycast addresses, multicast
1152 			 *    addresses, and the unspecified address MUST
1153 			 *    NOT be included in a candidate set.
1154 			 */
1155 			if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1156 			    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1157 				continue;
1158 
1159 			score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1160 
1161 			if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1162 				     score->addr_type & IPV6_ADDR_MULTICAST)) {
1163 				LIMIT_NETDEBUG(KERN_DEBUG
1164 					       "ADDRCONF: unspecified / multicast address "
1165 					       "assigned as unicast address on %s",
1166 					       dev->name);
1167 				continue;
1168 			}
1169 
1170 			score->rule = -1;
1171 			bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1172 
1173 			for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1174 				int minihiscore, miniscore;
1175 
1176 				minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
1177 				miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
1178 
1179 				if (minihiscore > miniscore) {
1180 					if (i == IPV6_SADDR_RULE_SCOPE &&
1181 					    score->scopedist > 0) {
1182 						/*
1183 						 * special case:
1184 						 * each remaining entry
1185 						 * has too small (not enough)
1186 						 * scope, because ifa entries
1187 						 * are sorted by their scope
1188 						 * values.
1189 						 */
1190 						goto try_nextdev;
1191 					}
1192 					break;
1193 				} else if (minihiscore < miniscore) {
1194 					if (hiscore->ifa)
1195 						in6_ifa_put(hiscore->ifa);
1196 
1197 					in6_ifa_hold(score->ifa);
1198 
1199 					swap(hiscore, score);
1200 
1201 					/* restore our iterator */
1202 					score->ifa = hiscore->ifa;
1203 
1204 					break;
1205 				}
1206 			}
1207 		}
1208 try_nextdev:
1209 		read_unlock_bh(&idev->lock);
1210 	}
1211 	rcu_read_unlock();
1212 
1213 	if (!hiscore->ifa)
1214 		return -EADDRNOTAVAIL;
1215 
1216 	*saddr = hiscore->ifa->addr;
1217 	in6_ifa_put(hiscore->ifa);
1218 	return 0;
1219 }
1220 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1221 
1222 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1223 		    unsigned char banned_flags)
1224 {
1225 	struct inet6_dev *idev;
1226 	int err = -EADDRNOTAVAIL;
1227 
1228 	rcu_read_lock();
1229 	idev = __in6_dev_get(dev);
1230 	if (idev) {
1231 		struct inet6_ifaddr *ifp;
1232 
1233 		read_lock_bh(&idev->lock);
1234 		list_for_each_entry(ifp, &idev->addr_list, if_list) {
1235 			if (ifp->scope == IFA_LINK &&
1236 			    !(ifp->flags & banned_flags)) {
1237 				*addr = ifp->addr;
1238 				err = 0;
1239 				break;
1240 			}
1241 		}
1242 		read_unlock_bh(&idev->lock);
1243 	}
1244 	rcu_read_unlock();
1245 	return err;
1246 }
1247 
1248 static int ipv6_count_addresses(struct inet6_dev *idev)
1249 {
1250 	int cnt = 0;
1251 	struct inet6_ifaddr *ifp;
1252 
1253 	read_lock_bh(&idev->lock);
1254 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1255 		cnt++;
1256 	read_unlock_bh(&idev->lock);
1257 	return cnt;
1258 }
1259 
1260 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1261 		  struct net_device *dev, int strict)
1262 {
1263 	struct inet6_ifaddr *ifp;
1264 	struct hlist_node *node;
1265 	unsigned int hash = inet6_addr_hash(addr);
1266 
1267 	rcu_read_lock_bh();
1268 	hlist_for_each_entry_rcu(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1269 		if (!net_eq(dev_net(ifp->idev->dev), net))
1270 			continue;
1271 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1272 		    !(ifp->flags&IFA_F_TENTATIVE) &&
1273 		    (dev == NULL || ifp->idev->dev == dev ||
1274 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1275 			rcu_read_unlock_bh();
1276 			return 1;
1277 		}
1278 	}
1279 
1280 	rcu_read_unlock_bh();
1281 	return 0;
1282 }
1283 EXPORT_SYMBOL(ipv6_chk_addr);
1284 
1285 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1286 			       struct net_device *dev)
1287 {
1288 	unsigned int hash = inet6_addr_hash(addr);
1289 	struct inet6_ifaddr *ifp;
1290 	struct hlist_node *node;
1291 
1292 	hlist_for_each_entry(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1293 		if (!net_eq(dev_net(ifp->idev->dev), net))
1294 			continue;
1295 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1296 			if (dev == NULL || ifp->idev->dev == dev)
1297 				return true;
1298 		}
1299 	}
1300 	return false;
1301 }
1302 
1303 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1304 {
1305 	struct inet6_dev *idev;
1306 	struct inet6_ifaddr *ifa;
1307 	int	onlink;
1308 
1309 	onlink = 0;
1310 	rcu_read_lock();
1311 	idev = __in6_dev_get(dev);
1312 	if (idev) {
1313 		read_lock_bh(&idev->lock);
1314 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1315 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1316 						   ifa->prefix_len);
1317 			if (onlink)
1318 				break;
1319 		}
1320 		read_unlock_bh(&idev->lock);
1321 	}
1322 	rcu_read_unlock();
1323 	return onlink;
1324 }
1325 EXPORT_SYMBOL(ipv6_chk_prefix);
1326 
1327 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1328 				     struct net_device *dev, int strict)
1329 {
1330 	struct inet6_ifaddr *ifp, *result = NULL;
1331 	unsigned int hash = inet6_addr_hash(addr);
1332 	struct hlist_node *node;
1333 
1334 	rcu_read_lock_bh();
1335 	hlist_for_each_entry_rcu_bh(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1336 		if (!net_eq(dev_net(ifp->idev->dev), net))
1337 			continue;
1338 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1339 			if (dev == NULL || ifp->idev->dev == dev ||
1340 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1341 				result = ifp;
1342 				in6_ifa_hold(ifp);
1343 				break;
1344 			}
1345 		}
1346 	}
1347 	rcu_read_unlock_bh();
1348 
1349 	return result;
1350 }
1351 
1352 /* Gets referenced address, destroys ifaddr */
1353 
1354 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1355 {
1356 	if (ifp->flags&IFA_F_PERMANENT) {
1357 		spin_lock_bh(&ifp->lock);
1358 		addrconf_del_timer(ifp);
1359 		ifp->flags |= IFA_F_TENTATIVE;
1360 		if (dad_failed)
1361 			ifp->flags |= IFA_F_DADFAILED;
1362 		spin_unlock_bh(&ifp->lock);
1363 		if (dad_failed)
1364 			ipv6_ifa_notify(0, ifp);
1365 		in6_ifa_put(ifp);
1366 #ifdef CONFIG_IPV6_PRIVACY
1367 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1368 		struct inet6_ifaddr *ifpub;
1369 		spin_lock_bh(&ifp->lock);
1370 		ifpub = ifp->ifpub;
1371 		if (ifpub) {
1372 			in6_ifa_hold(ifpub);
1373 			spin_unlock_bh(&ifp->lock);
1374 			ipv6_create_tempaddr(ifpub, ifp);
1375 			in6_ifa_put(ifpub);
1376 		} else {
1377 			spin_unlock_bh(&ifp->lock);
1378 		}
1379 		ipv6_del_addr(ifp);
1380 #endif
1381 	} else
1382 		ipv6_del_addr(ifp);
1383 }
1384 
1385 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1386 {
1387 	int err = -ENOENT;
1388 
1389 	spin_lock(&ifp->state_lock);
1390 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1391 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1392 		err = 0;
1393 	}
1394 	spin_unlock(&ifp->state_lock);
1395 
1396 	return err;
1397 }
1398 
1399 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1400 {
1401 	struct inet6_dev *idev = ifp->idev;
1402 
1403 	if (addrconf_dad_end(ifp)) {
1404 		in6_ifa_put(ifp);
1405 		return;
1406 	}
1407 
1408 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1409 			     ifp->idev->dev->name, &ifp->addr);
1410 
1411 	if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1412 		struct in6_addr addr;
1413 
1414 		addr.s6_addr32[0] = htonl(0xfe800000);
1415 		addr.s6_addr32[1] = 0;
1416 
1417 		if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1418 		    ipv6_addr_equal(&ifp->addr, &addr)) {
1419 			/* DAD failed for link-local based on MAC address */
1420 			idev->cnf.disable_ipv6 = 1;
1421 
1422 			pr_info("%s: IPv6 being disabled!\n",
1423 				ifp->idev->dev->name);
1424 		}
1425 	}
1426 
1427 	addrconf_dad_stop(ifp, 1);
1428 }
1429 
1430 /* Join to solicited addr multicast group. */
1431 
1432 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
1433 {
1434 	struct in6_addr maddr;
1435 
1436 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1437 		return;
1438 
1439 	addrconf_addr_solict_mult(addr, &maddr);
1440 	ipv6_dev_mc_inc(dev, &maddr);
1441 }
1442 
1443 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
1444 {
1445 	struct in6_addr maddr;
1446 
1447 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1448 		return;
1449 
1450 	addrconf_addr_solict_mult(addr, &maddr);
1451 	__ipv6_dev_mc_dec(idev, &maddr);
1452 }
1453 
1454 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1455 {
1456 	struct in6_addr addr;
1457 	if (ifp->prefix_len == 127) /* RFC 6164 */
1458 		return;
1459 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1460 	if (ipv6_addr_any(&addr))
1461 		return;
1462 	ipv6_dev_ac_inc(ifp->idev->dev, &addr);
1463 }
1464 
1465 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1466 {
1467 	struct in6_addr addr;
1468 	if (ifp->prefix_len == 127) /* RFC 6164 */
1469 		return;
1470 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1471 	if (ipv6_addr_any(&addr))
1472 		return;
1473 	__ipv6_dev_ac_dec(ifp->idev, &addr);
1474 }
1475 
1476 static int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
1477 {
1478 	if (dev->addr_len != ETH_ALEN)
1479 		return -1;
1480 	memcpy(eui, dev->dev_addr, 3);
1481 	memcpy(eui + 5, dev->dev_addr + 3, 3);
1482 
1483 	/*
1484 	 * The zSeries OSA network cards can be shared among various
1485 	 * OS instances, but the OSA cards have only one MAC address.
1486 	 * This leads to duplicate address conflicts in conjunction
1487 	 * with IPv6 if more than one instance uses the same card.
1488 	 *
1489 	 * The driver for these cards can deliver a unique 16-bit
1490 	 * identifier for each instance sharing the same card.  It is
1491 	 * placed instead of 0xFFFE in the interface identifier.  The
1492 	 * "u" bit of the interface identifier is not inverted in this
1493 	 * case.  Hence the resulting interface identifier has local
1494 	 * scope according to RFC2373.
1495 	 */
1496 	if (dev->dev_id) {
1497 		eui[3] = (dev->dev_id >> 8) & 0xFF;
1498 		eui[4] = dev->dev_id & 0xFF;
1499 	} else {
1500 		eui[3] = 0xFF;
1501 		eui[4] = 0xFE;
1502 		eui[0] ^= 2;
1503 	}
1504 	return 0;
1505 }
1506 
1507 static int addrconf_ifid_eui64(u8 *eui, struct net_device *dev)
1508 {
1509 	if (dev->addr_len != IEEE802154_ADDR_LEN)
1510 		return -1;
1511 	memcpy(eui, dev->dev_addr, 8);
1512 	return 0;
1513 }
1514 
1515 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
1516 {
1517 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
1518 	if (dev->addr_len != ARCNET_ALEN)
1519 		return -1;
1520 	memset(eui, 0, 7);
1521 	eui[7] = *(u8 *)dev->dev_addr;
1522 	return 0;
1523 }
1524 
1525 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
1526 {
1527 	if (dev->addr_len != INFINIBAND_ALEN)
1528 		return -1;
1529 	memcpy(eui, dev->dev_addr + 12, 8);
1530 	eui[0] |= 2;
1531 	return 0;
1532 }
1533 
1534 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
1535 {
1536 	if (addr == 0)
1537 		return -1;
1538 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
1539 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
1540 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
1541 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
1542 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
1543 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
1544 	eui[1] = 0;
1545 	eui[2] = 0x5E;
1546 	eui[3] = 0xFE;
1547 	memcpy(eui + 4, &addr, 4);
1548 	return 0;
1549 }
1550 
1551 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
1552 {
1553 	if (dev->priv_flags & IFF_ISATAP)
1554 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1555 	return -1;
1556 }
1557 
1558 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
1559 {
1560 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1561 }
1562 
1563 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
1564 {
1565 	switch (dev->type) {
1566 	case ARPHRD_ETHER:
1567 	case ARPHRD_FDDI:
1568 		return addrconf_ifid_eui48(eui, dev);
1569 	case ARPHRD_ARCNET:
1570 		return addrconf_ifid_arcnet(eui, dev);
1571 	case ARPHRD_INFINIBAND:
1572 		return addrconf_ifid_infiniband(eui, dev);
1573 	case ARPHRD_SIT:
1574 		return addrconf_ifid_sit(eui, dev);
1575 	case ARPHRD_IPGRE:
1576 		return addrconf_ifid_gre(eui, dev);
1577 	case ARPHRD_IEEE802154:
1578 		return addrconf_ifid_eui64(eui, dev);
1579 	}
1580 	return -1;
1581 }
1582 
1583 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
1584 {
1585 	int err = -1;
1586 	struct inet6_ifaddr *ifp;
1587 
1588 	read_lock_bh(&idev->lock);
1589 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
1590 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
1591 			memcpy(eui, ifp->addr.s6_addr+8, 8);
1592 			err = 0;
1593 			break;
1594 		}
1595 	}
1596 	read_unlock_bh(&idev->lock);
1597 	return err;
1598 }
1599 
1600 #ifdef CONFIG_IPV6_PRIVACY
1601 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
1602 static void __ipv6_regen_rndid(struct inet6_dev *idev)
1603 {
1604 regen:
1605 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
1606 	idev->rndid[0] &= ~0x02;
1607 
1608 	/*
1609 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
1610 	 * check if generated address is not inappropriate
1611 	 *
1612 	 *  - Reserved subnet anycast (RFC 2526)
1613 	 *	11111101 11....11 1xxxxxxx
1614 	 *  - ISATAP (RFC4214) 6.1
1615 	 *	00-00-5E-FE-xx-xx-xx-xx
1616 	 *  - value 0
1617 	 *  - XXX: already assigned to an address on the device
1618 	 */
1619 	if (idev->rndid[0] == 0xfd &&
1620 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
1621 	    (idev->rndid[7]&0x80))
1622 		goto regen;
1623 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
1624 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
1625 			goto regen;
1626 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
1627 			goto regen;
1628 	}
1629 }
1630 
1631 static void ipv6_regen_rndid(unsigned long data)
1632 {
1633 	struct inet6_dev *idev = (struct inet6_dev *) data;
1634 	unsigned long expires;
1635 
1636 	rcu_read_lock_bh();
1637 	write_lock_bh(&idev->lock);
1638 
1639 	if (idev->dead)
1640 		goto out;
1641 
1642 	__ipv6_regen_rndid(idev);
1643 
1644 	expires = jiffies +
1645 		idev->cnf.temp_prefered_lft * HZ -
1646 		idev->cnf.regen_max_retry * idev->cnf.dad_transmits * idev->nd_parms->retrans_time -
1647 		idev->cnf.max_desync_factor * HZ;
1648 	if (time_before(expires, jiffies)) {
1649 		pr_warn("%s: too short regeneration interval; timer disabled for %s\n",
1650 			__func__, idev->dev->name);
1651 		goto out;
1652 	}
1653 
1654 	if (!mod_timer(&idev->regen_timer, expires))
1655 		in6_dev_hold(idev);
1656 
1657 out:
1658 	write_unlock_bh(&idev->lock);
1659 	rcu_read_unlock_bh();
1660 	in6_dev_put(idev);
1661 }
1662 
1663 static void  __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
1664 {
1665 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
1666 		__ipv6_regen_rndid(idev);
1667 }
1668 #endif
1669 
1670 /*
1671  *	Add prefix route.
1672  */
1673 
1674 static void
1675 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
1676 		      unsigned long expires, u32 flags)
1677 {
1678 	struct fib6_config cfg = {
1679 		.fc_table = RT6_TABLE_PREFIX,
1680 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1681 		.fc_ifindex = dev->ifindex,
1682 		.fc_expires = expires,
1683 		.fc_dst_len = plen,
1684 		.fc_flags = RTF_UP | flags,
1685 		.fc_nlinfo.nl_net = dev_net(dev),
1686 		.fc_protocol = RTPROT_KERNEL,
1687 	};
1688 
1689 	cfg.fc_dst = *pfx;
1690 
1691 	/* Prevent useless cloning on PtP SIT.
1692 	   This thing is done here expecting that the whole
1693 	   class of non-broadcast devices need not cloning.
1694 	 */
1695 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
1696 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
1697 		cfg.fc_flags |= RTF_NONEXTHOP;
1698 #endif
1699 
1700 	ip6_route_add(&cfg);
1701 }
1702 
1703 
1704 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
1705 						  int plen,
1706 						  const struct net_device *dev,
1707 						  u32 flags, u32 noflags)
1708 {
1709 	struct fib6_node *fn;
1710 	struct rt6_info *rt = NULL;
1711 	struct fib6_table *table;
1712 
1713 	table = fib6_get_table(dev_net(dev), RT6_TABLE_PREFIX);
1714 	if (table == NULL)
1715 		return NULL;
1716 
1717 	read_lock_bh(&table->tb6_lock);
1718 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
1719 	if (!fn)
1720 		goto out;
1721 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1722 		if (rt->dst.dev->ifindex != dev->ifindex)
1723 			continue;
1724 		if ((rt->rt6i_flags & flags) != flags)
1725 			continue;
1726 		if ((noflags != 0) && ((rt->rt6i_flags & flags) != 0))
1727 			continue;
1728 		dst_hold(&rt->dst);
1729 		break;
1730 	}
1731 out:
1732 	read_unlock_bh(&table->tb6_lock);
1733 	return rt;
1734 }
1735 
1736 
1737 /* Create "default" multicast route to the interface */
1738 
1739 static void addrconf_add_mroute(struct net_device *dev)
1740 {
1741 	struct fib6_config cfg = {
1742 		.fc_table = RT6_TABLE_LOCAL,
1743 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1744 		.fc_ifindex = dev->ifindex,
1745 		.fc_dst_len = 8,
1746 		.fc_flags = RTF_UP,
1747 		.fc_nlinfo.nl_net = dev_net(dev),
1748 	};
1749 
1750 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
1751 
1752 	ip6_route_add(&cfg);
1753 }
1754 
1755 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
1756 static void sit_route_add(struct net_device *dev)
1757 {
1758 	struct fib6_config cfg = {
1759 		.fc_table = RT6_TABLE_MAIN,
1760 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1761 		.fc_ifindex = dev->ifindex,
1762 		.fc_dst_len = 96,
1763 		.fc_flags = RTF_UP | RTF_NONEXTHOP,
1764 		.fc_nlinfo.nl_net = dev_net(dev),
1765 	};
1766 
1767 	/* prefix length - 96 bits "::d.d.d.d" */
1768 	ip6_route_add(&cfg);
1769 }
1770 #endif
1771 
1772 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
1773 {
1774 	struct inet6_dev *idev;
1775 
1776 	ASSERT_RTNL();
1777 
1778 	idev = ipv6_find_idev(dev);
1779 	if (!idev)
1780 		return ERR_PTR(-ENOBUFS);
1781 
1782 	if (idev->cnf.disable_ipv6)
1783 		return ERR_PTR(-EACCES);
1784 
1785 	/* Add default multicast route */
1786 	if (!(dev->flags & IFF_LOOPBACK))
1787 		addrconf_add_mroute(dev);
1788 
1789 	return idev;
1790 }
1791 
1792 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
1793 {
1794 	struct prefix_info *pinfo;
1795 	__u32 valid_lft;
1796 	__u32 prefered_lft;
1797 	int addr_type;
1798 	struct inet6_dev *in6_dev;
1799 	struct net *net = dev_net(dev);
1800 
1801 	pinfo = (struct prefix_info *) opt;
1802 
1803 	if (len < sizeof(struct prefix_info)) {
1804 		ADBG(("addrconf: prefix option too short\n"));
1805 		return;
1806 	}
1807 
1808 	/*
1809 	 *	Validation checks ([ADDRCONF], page 19)
1810 	 */
1811 
1812 	addr_type = ipv6_addr_type(&pinfo->prefix);
1813 
1814 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
1815 		return;
1816 
1817 	valid_lft = ntohl(pinfo->valid);
1818 	prefered_lft = ntohl(pinfo->prefered);
1819 
1820 	if (prefered_lft > valid_lft) {
1821 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
1822 		return;
1823 	}
1824 
1825 	in6_dev = in6_dev_get(dev);
1826 
1827 	if (in6_dev == NULL) {
1828 		net_dbg_ratelimited("addrconf: device %s not configured\n",
1829 				    dev->name);
1830 		return;
1831 	}
1832 
1833 	/*
1834 	 *	Two things going on here:
1835 	 *	1) Add routes for on-link prefixes
1836 	 *	2) Configure prefixes with the auto flag set
1837 	 */
1838 
1839 	if (pinfo->onlink) {
1840 		struct rt6_info *rt;
1841 		unsigned long rt_expires;
1842 
1843 		/* Avoid arithmetic overflow. Really, we could
1844 		 * save rt_expires in seconds, likely valid_lft,
1845 		 * but it would require division in fib gc, that it
1846 		 * not good.
1847 		 */
1848 		if (HZ > USER_HZ)
1849 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
1850 		else
1851 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
1852 
1853 		if (addrconf_finite_timeout(rt_expires))
1854 			rt_expires *= HZ;
1855 
1856 		rt = addrconf_get_prefix_route(&pinfo->prefix,
1857 					       pinfo->prefix_len,
1858 					       dev,
1859 					       RTF_ADDRCONF | RTF_PREFIX_RT,
1860 					       RTF_GATEWAY | RTF_DEFAULT);
1861 
1862 		if (rt) {
1863 			/* Autoconf prefix route */
1864 			if (valid_lft == 0) {
1865 				ip6_del_rt(rt);
1866 				rt = NULL;
1867 			} else if (addrconf_finite_timeout(rt_expires)) {
1868 				/* not infinity */
1869 				rt6_set_expires(rt, jiffies + rt_expires);
1870 			} else {
1871 				rt6_clean_expires(rt);
1872 			}
1873 		} else if (valid_lft) {
1874 			clock_t expires = 0;
1875 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
1876 			if (addrconf_finite_timeout(rt_expires)) {
1877 				/* not infinity */
1878 				flags |= RTF_EXPIRES;
1879 				expires = jiffies_to_clock_t(rt_expires);
1880 			}
1881 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
1882 					      dev, expires, flags);
1883 		}
1884 		if (rt)
1885 			dst_release(&rt->dst);
1886 	}
1887 
1888 	/* Try to figure out our local address for this prefix */
1889 
1890 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
1891 		struct inet6_ifaddr *ifp;
1892 		struct in6_addr addr;
1893 		int create = 0, update_lft = 0;
1894 
1895 		if (pinfo->prefix_len == 64) {
1896 			memcpy(&addr, &pinfo->prefix, 8);
1897 			if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
1898 			    ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
1899 				in6_dev_put(in6_dev);
1900 				return;
1901 			}
1902 			goto ok;
1903 		}
1904 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
1905 				    pinfo->prefix_len);
1906 		in6_dev_put(in6_dev);
1907 		return;
1908 
1909 ok:
1910 
1911 		ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
1912 
1913 		if (ifp == NULL && valid_lft) {
1914 			int max_addresses = in6_dev->cnf.max_addresses;
1915 			u32 addr_flags = 0;
1916 
1917 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1918 			if (in6_dev->cnf.optimistic_dad &&
1919 			    !net->ipv6.devconf_all->forwarding && sllao)
1920 				addr_flags = IFA_F_OPTIMISTIC;
1921 #endif
1922 
1923 			/* Do not allow to create too much of autoconfigured
1924 			 * addresses; this would be too easy way to crash kernel.
1925 			 */
1926 			if (!max_addresses ||
1927 			    ipv6_count_addresses(in6_dev) < max_addresses)
1928 				ifp = ipv6_add_addr(in6_dev, &addr, pinfo->prefix_len,
1929 						    addr_type&IPV6_ADDR_SCOPE_MASK,
1930 						    addr_flags);
1931 
1932 			if (!ifp || IS_ERR(ifp)) {
1933 				in6_dev_put(in6_dev);
1934 				return;
1935 			}
1936 
1937 			update_lft = create = 1;
1938 			ifp->cstamp = jiffies;
1939 			addrconf_dad_start(ifp);
1940 		}
1941 
1942 		if (ifp) {
1943 			int flags;
1944 			unsigned long now;
1945 #ifdef CONFIG_IPV6_PRIVACY
1946 			struct inet6_ifaddr *ift;
1947 #endif
1948 			u32 stored_lft;
1949 
1950 			/* update lifetime (RFC2462 5.5.3 e) */
1951 			spin_lock(&ifp->lock);
1952 			now = jiffies;
1953 			if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
1954 				stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
1955 			else
1956 				stored_lft = 0;
1957 			if (!update_lft && stored_lft) {
1958 				if (valid_lft > MIN_VALID_LIFETIME ||
1959 				    valid_lft > stored_lft)
1960 					update_lft = 1;
1961 				else if (stored_lft <= MIN_VALID_LIFETIME) {
1962 					/* valid_lft <= stored_lft is always true */
1963 					/*
1964 					 * RFC 4862 Section 5.5.3e:
1965 					 * "Note that the preferred lifetime of
1966 					 *  the corresponding address is always
1967 					 *  reset to the Preferred Lifetime in
1968 					 *  the received Prefix Information
1969 					 *  option, regardless of whether the
1970 					 *  valid lifetime is also reset or
1971 					 *  ignored."
1972 					 *
1973 					 *  So if the preferred lifetime in
1974 					 *  this advertisement is different
1975 					 *  than what we have stored, but the
1976 					 *  valid lifetime is invalid, just
1977 					 *  reset prefered_lft.
1978 					 *
1979 					 *  We must set the valid lifetime
1980 					 *  to the stored lifetime since we'll
1981 					 *  be updating the timestamp below,
1982 					 *  else we'll set it back to the
1983 					 *  minimum.
1984 					 */
1985 					if (prefered_lft != ifp->prefered_lft) {
1986 						valid_lft = stored_lft;
1987 						update_lft = 1;
1988 					}
1989 				} else {
1990 					valid_lft = MIN_VALID_LIFETIME;
1991 					if (valid_lft < prefered_lft)
1992 						prefered_lft = valid_lft;
1993 					update_lft = 1;
1994 				}
1995 			}
1996 
1997 			if (update_lft) {
1998 				ifp->valid_lft = valid_lft;
1999 				ifp->prefered_lft = prefered_lft;
2000 				ifp->tstamp = now;
2001 				flags = ifp->flags;
2002 				ifp->flags &= ~IFA_F_DEPRECATED;
2003 				spin_unlock(&ifp->lock);
2004 
2005 				if (!(flags&IFA_F_TENTATIVE))
2006 					ipv6_ifa_notify(0, ifp);
2007 			} else
2008 				spin_unlock(&ifp->lock);
2009 
2010 #ifdef CONFIG_IPV6_PRIVACY
2011 			read_lock_bh(&in6_dev->lock);
2012 			/* update all temporary addresses in the list */
2013 			list_for_each_entry(ift, &in6_dev->tempaddr_list,
2014 					    tmp_list) {
2015 				int age, max_valid, max_prefered;
2016 
2017 				if (ifp != ift->ifpub)
2018 					continue;
2019 
2020 				/*
2021 				 * RFC 4941 section 3.3:
2022 				 * If a received option will extend the lifetime
2023 				 * of a public address, the lifetimes of
2024 				 * temporary addresses should be extended,
2025 				 * subject to the overall constraint that no
2026 				 * temporary addresses should ever remain
2027 				 * "valid" or "preferred" for a time longer than
2028 				 * (TEMP_VALID_LIFETIME) or
2029 				 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR),
2030 				 * respectively.
2031 				 */
2032 				age = (now - ift->cstamp) / HZ;
2033 				max_valid = in6_dev->cnf.temp_valid_lft - age;
2034 				if (max_valid < 0)
2035 					max_valid = 0;
2036 
2037 				max_prefered = in6_dev->cnf.temp_prefered_lft -
2038 					       in6_dev->cnf.max_desync_factor -
2039 					       age;
2040 				if (max_prefered < 0)
2041 					max_prefered = 0;
2042 
2043 				if (valid_lft > max_valid)
2044 					valid_lft = max_valid;
2045 
2046 				if (prefered_lft > max_prefered)
2047 					prefered_lft = max_prefered;
2048 
2049 				spin_lock(&ift->lock);
2050 				flags = ift->flags;
2051 				ift->valid_lft = valid_lft;
2052 				ift->prefered_lft = prefered_lft;
2053 				ift->tstamp = now;
2054 				if (prefered_lft > 0)
2055 					ift->flags &= ~IFA_F_DEPRECATED;
2056 
2057 				spin_unlock(&ift->lock);
2058 				if (!(flags&IFA_F_TENTATIVE))
2059 					ipv6_ifa_notify(0, ift);
2060 			}
2061 
2062 			if ((create || list_empty(&in6_dev->tempaddr_list)) && in6_dev->cnf.use_tempaddr > 0) {
2063 				/*
2064 				 * When a new public address is created as
2065 				 * described in [ADDRCONF], also create a new
2066 				 * temporary address. Also create a temporary
2067 				 * address if it's enabled but no temporary
2068 				 * address currently exists.
2069 				 */
2070 				read_unlock_bh(&in6_dev->lock);
2071 				ipv6_create_tempaddr(ifp, NULL);
2072 			} else {
2073 				read_unlock_bh(&in6_dev->lock);
2074 			}
2075 #endif
2076 			in6_ifa_put(ifp);
2077 			addrconf_verify(0);
2078 		}
2079 	}
2080 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2081 	in6_dev_put(in6_dev);
2082 }
2083 
2084 /*
2085  *	Set destination address.
2086  *	Special case for SIT interfaces where we create a new "virtual"
2087  *	device.
2088  */
2089 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2090 {
2091 	struct in6_ifreq ireq;
2092 	struct net_device *dev;
2093 	int err = -EINVAL;
2094 
2095 	rtnl_lock();
2096 
2097 	err = -EFAULT;
2098 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2099 		goto err_exit;
2100 
2101 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2102 
2103 	err = -ENODEV;
2104 	if (dev == NULL)
2105 		goto err_exit;
2106 
2107 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
2108 	if (dev->type == ARPHRD_SIT) {
2109 		const struct net_device_ops *ops = dev->netdev_ops;
2110 		struct ifreq ifr;
2111 		struct ip_tunnel_parm p;
2112 
2113 		err = -EADDRNOTAVAIL;
2114 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2115 			goto err_exit;
2116 
2117 		memset(&p, 0, sizeof(p));
2118 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2119 		p.iph.saddr = 0;
2120 		p.iph.version = 4;
2121 		p.iph.ihl = 5;
2122 		p.iph.protocol = IPPROTO_IPV6;
2123 		p.iph.ttl = 64;
2124 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2125 
2126 		if (ops->ndo_do_ioctl) {
2127 			mm_segment_t oldfs = get_fs();
2128 
2129 			set_fs(KERNEL_DS);
2130 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2131 			set_fs(oldfs);
2132 		} else
2133 			err = -EOPNOTSUPP;
2134 
2135 		if (err == 0) {
2136 			err = -ENOBUFS;
2137 			dev = __dev_get_by_name(net, p.name);
2138 			if (!dev)
2139 				goto err_exit;
2140 			err = dev_open(dev);
2141 		}
2142 	}
2143 #endif
2144 
2145 err_exit:
2146 	rtnl_unlock();
2147 	return err;
2148 }
2149 
2150 /*
2151  *	Manual configuration of address on an interface
2152  */
2153 static int inet6_addr_add(struct net *net, int ifindex, const struct in6_addr *pfx,
2154 			  unsigned int plen, __u8 ifa_flags, __u32 prefered_lft,
2155 			  __u32 valid_lft)
2156 {
2157 	struct inet6_ifaddr *ifp;
2158 	struct inet6_dev *idev;
2159 	struct net_device *dev;
2160 	int scope;
2161 	u32 flags;
2162 	clock_t expires;
2163 	unsigned long timeout;
2164 
2165 	ASSERT_RTNL();
2166 
2167 	if (plen > 128)
2168 		return -EINVAL;
2169 
2170 	/* check the lifetime */
2171 	if (!valid_lft || prefered_lft > valid_lft)
2172 		return -EINVAL;
2173 
2174 	dev = __dev_get_by_index(net, ifindex);
2175 	if (!dev)
2176 		return -ENODEV;
2177 
2178 	idev = addrconf_add_dev(dev);
2179 	if (IS_ERR(idev))
2180 		return PTR_ERR(idev);
2181 
2182 	scope = ipv6_addr_scope(pfx);
2183 
2184 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2185 	if (addrconf_finite_timeout(timeout)) {
2186 		expires = jiffies_to_clock_t(timeout * HZ);
2187 		valid_lft = timeout;
2188 		flags = RTF_EXPIRES;
2189 	} else {
2190 		expires = 0;
2191 		flags = 0;
2192 		ifa_flags |= IFA_F_PERMANENT;
2193 	}
2194 
2195 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2196 	if (addrconf_finite_timeout(timeout)) {
2197 		if (timeout == 0)
2198 			ifa_flags |= IFA_F_DEPRECATED;
2199 		prefered_lft = timeout;
2200 	}
2201 
2202 	ifp = ipv6_add_addr(idev, pfx, plen, scope, ifa_flags);
2203 
2204 	if (!IS_ERR(ifp)) {
2205 		spin_lock_bh(&ifp->lock);
2206 		ifp->valid_lft = valid_lft;
2207 		ifp->prefered_lft = prefered_lft;
2208 		ifp->tstamp = jiffies;
2209 		spin_unlock_bh(&ifp->lock);
2210 
2211 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2212 				      expires, flags);
2213 		/*
2214 		 * Note that section 3.1 of RFC 4429 indicates
2215 		 * that the Optimistic flag should not be set for
2216 		 * manually configured addresses
2217 		 */
2218 		addrconf_dad_start(ifp);
2219 		in6_ifa_put(ifp);
2220 		addrconf_verify(0);
2221 		return 0;
2222 	}
2223 
2224 	return PTR_ERR(ifp);
2225 }
2226 
2227 static int inet6_addr_del(struct net *net, int ifindex, const struct in6_addr *pfx,
2228 			  unsigned int plen)
2229 {
2230 	struct inet6_ifaddr *ifp;
2231 	struct inet6_dev *idev;
2232 	struct net_device *dev;
2233 
2234 	if (plen > 128)
2235 		return -EINVAL;
2236 
2237 	dev = __dev_get_by_index(net, ifindex);
2238 	if (!dev)
2239 		return -ENODEV;
2240 
2241 	if ((idev = __in6_dev_get(dev)) == NULL)
2242 		return -ENXIO;
2243 
2244 	read_lock_bh(&idev->lock);
2245 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2246 		if (ifp->prefix_len == plen &&
2247 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2248 			in6_ifa_hold(ifp);
2249 			read_unlock_bh(&idev->lock);
2250 
2251 			ipv6_del_addr(ifp);
2252 
2253 			/* If the last address is deleted administratively,
2254 			   disable IPv6 on this interface.
2255 			 */
2256 			if (list_empty(&idev->addr_list))
2257 				addrconf_ifdown(idev->dev, 1);
2258 			return 0;
2259 		}
2260 	}
2261 	read_unlock_bh(&idev->lock);
2262 	return -EADDRNOTAVAIL;
2263 }
2264 
2265 
2266 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2267 {
2268 	struct in6_ifreq ireq;
2269 	int err;
2270 
2271 	if (!capable(CAP_NET_ADMIN))
2272 		return -EPERM;
2273 
2274 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2275 		return -EFAULT;
2276 
2277 	rtnl_lock();
2278 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2279 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2280 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2281 	rtnl_unlock();
2282 	return err;
2283 }
2284 
2285 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2286 {
2287 	struct in6_ifreq ireq;
2288 	int err;
2289 
2290 	if (!capable(CAP_NET_ADMIN))
2291 		return -EPERM;
2292 
2293 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2294 		return -EFAULT;
2295 
2296 	rtnl_lock();
2297 	err = inet6_addr_del(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2298 			     ireq.ifr6_prefixlen);
2299 	rtnl_unlock();
2300 	return err;
2301 }
2302 
2303 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2304 		     int plen, int scope)
2305 {
2306 	struct inet6_ifaddr *ifp;
2307 
2308 	ifp = ipv6_add_addr(idev, addr, plen, scope, IFA_F_PERMANENT);
2309 	if (!IS_ERR(ifp)) {
2310 		spin_lock_bh(&ifp->lock);
2311 		ifp->flags &= ~IFA_F_TENTATIVE;
2312 		spin_unlock_bh(&ifp->lock);
2313 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2314 		in6_ifa_put(ifp);
2315 	}
2316 }
2317 
2318 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
2319 static void sit_add_v4_addrs(struct inet6_dev *idev)
2320 {
2321 	struct in6_addr addr;
2322 	struct net_device *dev;
2323 	struct net *net = dev_net(idev->dev);
2324 	int scope;
2325 
2326 	ASSERT_RTNL();
2327 
2328 	memset(&addr, 0, sizeof(struct in6_addr));
2329 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2330 
2331 	if (idev->dev->flags&IFF_POINTOPOINT) {
2332 		addr.s6_addr32[0] = htonl(0xfe800000);
2333 		scope = IFA_LINK;
2334 	} else {
2335 		scope = IPV6_ADDR_COMPATv4;
2336 	}
2337 
2338 	if (addr.s6_addr32[3]) {
2339 		add_addr(idev, &addr, 128, scope);
2340 		return;
2341 	}
2342 
2343 	for_each_netdev(net, dev) {
2344 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
2345 		if (in_dev && (dev->flags & IFF_UP)) {
2346 			struct in_ifaddr *ifa;
2347 
2348 			int flag = scope;
2349 
2350 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2351 				int plen;
2352 
2353 				addr.s6_addr32[3] = ifa->ifa_local;
2354 
2355 				if (ifa->ifa_scope == RT_SCOPE_LINK)
2356 					continue;
2357 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2358 					if (idev->dev->flags&IFF_POINTOPOINT)
2359 						continue;
2360 					flag |= IFA_HOST;
2361 				}
2362 				if (idev->dev->flags&IFF_POINTOPOINT)
2363 					plen = 64;
2364 				else
2365 					plen = 96;
2366 
2367 				add_addr(idev, &addr, plen, flag);
2368 			}
2369 		}
2370 	}
2371 }
2372 #endif
2373 
2374 static void init_loopback(struct net_device *dev)
2375 {
2376 	struct inet6_dev  *idev;
2377 
2378 	/* ::1 */
2379 
2380 	ASSERT_RTNL();
2381 
2382 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2383 		pr_debug("%s: add_dev failed\n", __func__);
2384 		return;
2385 	}
2386 
2387 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2388 }
2389 
2390 static void addrconf_add_linklocal(struct inet6_dev *idev, const struct in6_addr *addr)
2391 {
2392 	struct inet6_ifaddr *ifp;
2393 	u32 addr_flags = IFA_F_PERMANENT;
2394 
2395 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2396 	if (idev->cnf.optimistic_dad &&
2397 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
2398 		addr_flags |= IFA_F_OPTIMISTIC;
2399 #endif
2400 
2401 
2402 	ifp = ipv6_add_addr(idev, addr, 64, IFA_LINK, addr_flags);
2403 	if (!IS_ERR(ifp)) {
2404 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
2405 		addrconf_dad_start(ifp);
2406 		in6_ifa_put(ifp);
2407 	}
2408 }
2409 
2410 static void addrconf_dev_config(struct net_device *dev)
2411 {
2412 	struct in6_addr addr;
2413 	struct inet6_dev *idev;
2414 
2415 	ASSERT_RTNL();
2416 
2417 	if ((dev->type != ARPHRD_ETHER) &&
2418 	    (dev->type != ARPHRD_FDDI) &&
2419 	    (dev->type != ARPHRD_ARCNET) &&
2420 	    (dev->type != ARPHRD_INFINIBAND) &&
2421 	    (dev->type != ARPHRD_IEEE802154)) {
2422 		/* Alas, we support only Ethernet autoconfiguration. */
2423 		return;
2424 	}
2425 
2426 	idev = addrconf_add_dev(dev);
2427 	if (IS_ERR(idev))
2428 		return;
2429 
2430 	memset(&addr, 0, sizeof(struct in6_addr));
2431 	addr.s6_addr32[0] = htonl(0xFE800000);
2432 
2433 	if (ipv6_generate_eui64(addr.s6_addr + 8, dev) == 0)
2434 		addrconf_add_linklocal(idev, &addr);
2435 }
2436 
2437 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
2438 static void addrconf_sit_config(struct net_device *dev)
2439 {
2440 	struct inet6_dev *idev;
2441 
2442 	ASSERT_RTNL();
2443 
2444 	/*
2445 	 * Configure the tunnel with one of our IPv4
2446 	 * addresses... we should configure all of
2447 	 * our v4 addrs in the tunnel
2448 	 */
2449 
2450 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2451 		pr_debug("%s: add_dev failed\n", __func__);
2452 		return;
2453 	}
2454 
2455 	if (dev->priv_flags & IFF_ISATAP) {
2456 		struct in6_addr addr;
2457 
2458 		ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2459 		addrconf_prefix_route(&addr, 64, dev, 0, 0);
2460 		if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2461 			addrconf_add_linklocal(idev, &addr);
2462 		return;
2463 	}
2464 
2465 	sit_add_v4_addrs(idev);
2466 
2467 	if (dev->flags&IFF_POINTOPOINT)
2468 		addrconf_add_mroute(dev);
2469 	else
2470 		sit_route_add(dev);
2471 }
2472 #endif
2473 
2474 #if defined(CONFIG_NET_IPGRE) || defined(CONFIG_NET_IPGRE_MODULE)
2475 static void addrconf_gre_config(struct net_device *dev)
2476 {
2477 	struct inet6_dev *idev;
2478 	struct in6_addr addr;
2479 
2480 	pr_info("%s(%s)\n", __func__, dev->name);
2481 
2482 	ASSERT_RTNL();
2483 
2484 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2485 		pr_debug("%s: add_dev failed\n", __func__);
2486 		return;
2487 	}
2488 
2489 	ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2490 	addrconf_prefix_route(&addr, 64, dev, 0, 0);
2491 
2492 	if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2493 		addrconf_add_linklocal(idev, &addr);
2494 }
2495 #endif
2496 
2497 static inline int
2498 ipv6_inherit_linklocal(struct inet6_dev *idev, struct net_device *link_dev)
2499 {
2500 	struct in6_addr lladdr;
2501 
2502 	if (!ipv6_get_lladdr(link_dev, &lladdr, IFA_F_TENTATIVE)) {
2503 		addrconf_add_linklocal(idev, &lladdr);
2504 		return 0;
2505 	}
2506 	return -1;
2507 }
2508 
2509 static void ip6_tnl_add_linklocal(struct inet6_dev *idev)
2510 {
2511 	struct net_device *link_dev;
2512 	struct net *net = dev_net(idev->dev);
2513 
2514 	/* first try to inherit the link-local address from the link device */
2515 	if (idev->dev->iflink &&
2516 	    (link_dev = __dev_get_by_index(net, idev->dev->iflink))) {
2517 		if (!ipv6_inherit_linklocal(idev, link_dev))
2518 			return;
2519 	}
2520 	/* then try to inherit it from any device */
2521 	for_each_netdev(net, link_dev) {
2522 		if (!ipv6_inherit_linklocal(idev, link_dev))
2523 			return;
2524 	}
2525 	pr_debug("init ip6-ip6: add_linklocal failed\n");
2526 }
2527 
2528 /*
2529  * Autoconfigure tunnel with a link-local address so routing protocols,
2530  * DHCPv6, MLD etc. can be run over the virtual link
2531  */
2532 
2533 static void addrconf_ip6_tnl_config(struct net_device *dev)
2534 {
2535 	struct inet6_dev *idev;
2536 
2537 	ASSERT_RTNL();
2538 
2539 	idev = addrconf_add_dev(dev);
2540 	if (IS_ERR(idev)) {
2541 		pr_debug("init ip6-ip6: add_dev failed\n");
2542 		return;
2543 	}
2544 	ip6_tnl_add_linklocal(idev);
2545 }
2546 
2547 static int addrconf_notify(struct notifier_block *this, unsigned long event,
2548 			   void *data)
2549 {
2550 	struct net_device *dev = (struct net_device *) data;
2551 	struct inet6_dev *idev = __in6_dev_get(dev);
2552 	int run_pending = 0;
2553 	int err;
2554 
2555 	switch (event) {
2556 	case NETDEV_REGISTER:
2557 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2558 			idev = ipv6_add_dev(dev);
2559 			if (!idev)
2560 				return notifier_from_errno(-ENOMEM);
2561 		}
2562 		break;
2563 
2564 	case NETDEV_UP:
2565 	case NETDEV_CHANGE:
2566 		if (dev->flags & IFF_SLAVE)
2567 			break;
2568 
2569 		if (event == NETDEV_UP) {
2570 			if (!addrconf_qdisc_ok(dev)) {
2571 				/* device is not ready yet. */
2572 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
2573 					dev->name);
2574 				break;
2575 			}
2576 
2577 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
2578 				idev = ipv6_add_dev(dev);
2579 
2580 			if (idev) {
2581 				idev->if_flags |= IF_READY;
2582 				run_pending = 1;
2583 			}
2584 		} else {
2585 			if (!addrconf_qdisc_ok(dev)) {
2586 				/* device is still not ready. */
2587 				break;
2588 			}
2589 
2590 			if (idev) {
2591 				if (idev->if_flags & IF_READY)
2592 					/* device is already configured. */
2593 					break;
2594 				idev->if_flags |= IF_READY;
2595 			}
2596 
2597 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
2598 				dev->name);
2599 
2600 			run_pending = 1;
2601 		}
2602 
2603 		switch (dev->type) {
2604 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
2605 		case ARPHRD_SIT:
2606 			addrconf_sit_config(dev);
2607 			break;
2608 #endif
2609 #if defined(CONFIG_NET_IPGRE) || defined(CONFIG_NET_IPGRE_MODULE)
2610 		case ARPHRD_IPGRE:
2611 			addrconf_gre_config(dev);
2612 			break;
2613 #endif
2614 		case ARPHRD_TUNNEL6:
2615 			addrconf_ip6_tnl_config(dev);
2616 			break;
2617 		case ARPHRD_LOOPBACK:
2618 			init_loopback(dev);
2619 			break;
2620 
2621 		default:
2622 			addrconf_dev_config(dev);
2623 			break;
2624 		}
2625 
2626 		if (idev) {
2627 			if (run_pending)
2628 				addrconf_dad_run(idev);
2629 
2630 			/*
2631 			 * If the MTU changed during the interface down,
2632 			 * when the interface up, the changed MTU must be
2633 			 * reflected in the idev as well as routers.
2634 			 */
2635 			if (idev->cnf.mtu6 != dev->mtu &&
2636 			    dev->mtu >= IPV6_MIN_MTU) {
2637 				rt6_mtu_change(dev, dev->mtu);
2638 				idev->cnf.mtu6 = dev->mtu;
2639 			}
2640 			idev->tstamp = jiffies;
2641 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
2642 
2643 			/*
2644 			 * If the changed mtu during down is lower than
2645 			 * IPV6_MIN_MTU stop IPv6 on this interface.
2646 			 */
2647 			if (dev->mtu < IPV6_MIN_MTU)
2648 				addrconf_ifdown(dev, 1);
2649 		}
2650 		break;
2651 
2652 	case NETDEV_CHANGEMTU:
2653 		if (idev && dev->mtu >= IPV6_MIN_MTU) {
2654 			rt6_mtu_change(dev, dev->mtu);
2655 			idev->cnf.mtu6 = dev->mtu;
2656 			break;
2657 		}
2658 
2659 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2660 			idev = ipv6_add_dev(dev);
2661 			if (idev)
2662 				break;
2663 		}
2664 
2665 		/*
2666 		 * MTU falled under IPV6_MIN_MTU.
2667 		 * Stop IPv6 on this interface.
2668 		 */
2669 
2670 	case NETDEV_DOWN:
2671 	case NETDEV_UNREGISTER:
2672 		/*
2673 		 *	Remove all addresses from this interface.
2674 		 */
2675 		addrconf_ifdown(dev, event != NETDEV_DOWN);
2676 		break;
2677 
2678 	case NETDEV_CHANGENAME:
2679 		if (idev) {
2680 			snmp6_unregister_dev(idev);
2681 			addrconf_sysctl_unregister(idev);
2682 			addrconf_sysctl_register(idev);
2683 			err = snmp6_register_dev(idev);
2684 			if (err)
2685 				return notifier_from_errno(err);
2686 		}
2687 		break;
2688 
2689 	case NETDEV_PRE_TYPE_CHANGE:
2690 	case NETDEV_POST_TYPE_CHANGE:
2691 		addrconf_type_change(dev, event);
2692 		break;
2693 	}
2694 
2695 	return NOTIFY_OK;
2696 }
2697 
2698 /*
2699  *	addrconf module should be notified of a device going up
2700  */
2701 static struct notifier_block ipv6_dev_notf = {
2702 	.notifier_call = addrconf_notify,
2703 };
2704 
2705 static void addrconf_type_change(struct net_device *dev, unsigned long event)
2706 {
2707 	struct inet6_dev *idev;
2708 	ASSERT_RTNL();
2709 
2710 	idev = __in6_dev_get(dev);
2711 
2712 	if (event == NETDEV_POST_TYPE_CHANGE)
2713 		ipv6_mc_remap(idev);
2714 	else if (event == NETDEV_PRE_TYPE_CHANGE)
2715 		ipv6_mc_unmap(idev);
2716 }
2717 
2718 static int addrconf_ifdown(struct net_device *dev, int how)
2719 {
2720 	struct net *net = dev_net(dev);
2721 	struct inet6_dev *idev;
2722 	struct inet6_ifaddr *ifa;
2723 	int state, i;
2724 
2725 	ASSERT_RTNL();
2726 
2727 	rt6_ifdown(net, dev);
2728 	neigh_ifdown(&nd_tbl, dev);
2729 
2730 	idev = __in6_dev_get(dev);
2731 	if (idev == NULL)
2732 		return -ENODEV;
2733 
2734 	/*
2735 	 * Step 1: remove reference to ipv6 device from parent device.
2736 	 *	   Do not dev_put!
2737 	 */
2738 	if (how) {
2739 		idev->dead = 1;
2740 
2741 		/* protected by rtnl_lock */
2742 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
2743 
2744 		/* Step 1.5: remove snmp6 entry */
2745 		snmp6_unregister_dev(idev);
2746 
2747 	}
2748 
2749 	/* Step 2: clear hash table */
2750 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
2751 		struct hlist_head *h = &inet6_addr_lst[i];
2752 		struct hlist_node *n;
2753 
2754 		spin_lock_bh(&addrconf_hash_lock);
2755 	restart:
2756 		hlist_for_each_entry_rcu(ifa, n, h, addr_lst) {
2757 			if (ifa->idev == idev) {
2758 				hlist_del_init_rcu(&ifa->addr_lst);
2759 				addrconf_del_timer(ifa);
2760 				goto restart;
2761 			}
2762 		}
2763 		spin_unlock_bh(&addrconf_hash_lock);
2764 	}
2765 
2766 	write_lock_bh(&idev->lock);
2767 
2768 	/* Step 2: clear flags for stateless addrconf */
2769 	if (!how)
2770 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
2771 
2772 #ifdef CONFIG_IPV6_PRIVACY
2773 	if (how && del_timer(&idev->regen_timer))
2774 		in6_dev_put(idev);
2775 
2776 	/* Step 3: clear tempaddr list */
2777 	while (!list_empty(&idev->tempaddr_list)) {
2778 		ifa = list_first_entry(&idev->tempaddr_list,
2779 				       struct inet6_ifaddr, tmp_list);
2780 		list_del(&ifa->tmp_list);
2781 		write_unlock_bh(&idev->lock);
2782 		spin_lock_bh(&ifa->lock);
2783 
2784 		if (ifa->ifpub) {
2785 			in6_ifa_put(ifa->ifpub);
2786 			ifa->ifpub = NULL;
2787 		}
2788 		spin_unlock_bh(&ifa->lock);
2789 		in6_ifa_put(ifa);
2790 		write_lock_bh(&idev->lock);
2791 	}
2792 #endif
2793 
2794 	while (!list_empty(&idev->addr_list)) {
2795 		ifa = list_first_entry(&idev->addr_list,
2796 				       struct inet6_ifaddr, if_list);
2797 		addrconf_del_timer(ifa);
2798 
2799 		list_del(&ifa->if_list);
2800 
2801 		write_unlock_bh(&idev->lock);
2802 
2803 		spin_lock_bh(&ifa->state_lock);
2804 		state = ifa->state;
2805 		ifa->state = INET6_IFADDR_STATE_DEAD;
2806 		spin_unlock_bh(&ifa->state_lock);
2807 
2808 		if (state != INET6_IFADDR_STATE_DEAD) {
2809 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
2810 			atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifa);
2811 		}
2812 		in6_ifa_put(ifa);
2813 
2814 		write_lock_bh(&idev->lock);
2815 	}
2816 
2817 	write_unlock_bh(&idev->lock);
2818 
2819 	/* Step 5: Discard multicast list */
2820 	if (how)
2821 		ipv6_mc_destroy_dev(idev);
2822 	else
2823 		ipv6_mc_down(idev);
2824 
2825 	idev->tstamp = jiffies;
2826 
2827 	/* Last: Shot the device (if unregistered) */
2828 	if (how) {
2829 		addrconf_sysctl_unregister(idev);
2830 		neigh_parms_release(&nd_tbl, idev->nd_parms);
2831 		neigh_ifdown(&nd_tbl, dev);
2832 		in6_dev_put(idev);
2833 	}
2834 	return 0;
2835 }
2836 
2837 static void addrconf_rs_timer(unsigned long data)
2838 {
2839 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
2840 	struct inet6_dev *idev = ifp->idev;
2841 
2842 	read_lock(&idev->lock);
2843 	if (idev->dead || !(idev->if_flags & IF_READY))
2844 		goto out;
2845 
2846 	if (idev->cnf.forwarding)
2847 		goto out;
2848 
2849 	/* Announcement received after solicitation was sent */
2850 	if (idev->if_flags & IF_RA_RCVD)
2851 		goto out;
2852 
2853 	spin_lock(&ifp->lock);
2854 	if (ifp->probes++ < idev->cnf.rtr_solicits) {
2855 		/* The wait after the last probe can be shorter */
2856 		addrconf_mod_timer(ifp, AC_RS,
2857 				   (ifp->probes == idev->cnf.rtr_solicits) ?
2858 				   idev->cnf.rtr_solicit_delay :
2859 				   idev->cnf.rtr_solicit_interval);
2860 		spin_unlock(&ifp->lock);
2861 
2862 		ndisc_send_rs(idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
2863 	} else {
2864 		spin_unlock(&ifp->lock);
2865 		/*
2866 		 * Note: we do not support deprecated "all on-link"
2867 		 * assumption any longer.
2868 		 */
2869 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
2870 	}
2871 
2872 out:
2873 	read_unlock(&idev->lock);
2874 	in6_ifa_put(ifp);
2875 }
2876 
2877 /*
2878  *	Duplicate Address Detection
2879  */
2880 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
2881 {
2882 	unsigned long rand_num;
2883 	struct inet6_dev *idev = ifp->idev;
2884 
2885 	if (ifp->flags & IFA_F_OPTIMISTIC)
2886 		rand_num = 0;
2887 	else
2888 		rand_num = net_random() % (idev->cnf.rtr_solicit_delay ? : 1);
2889 
2890 	ifp->probes = idev->cnf.dad_transmits;
2891 	addrconf_mod_timer(ifp, AC_DAD, rand_num);
2892 }
2893 
2894 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
2895 {
2896 	struct inet6_dev *idev = ifp->idev;
2897 	struct net_device *dev = idev->dev;
2898 
2899 	addrconf_join_solict(dev, &ifp->addr);
2900 
2901 	net_srandom(ifp->addr.s6_addr32[3]);
2902 
2903 	read_lock_bh(&idev->lock);
2904 	spin_lock(&ifp->lock);
2905 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
2906 		goto out;
2907 
2908 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
2909 	    idev->cnf.accept_dad < 1 ||
2910 	    !(ifp->flags&IFA_F_TENTATIVE) ||
2911 	    ifp->flags & IFA_F_NODAD) {
2912 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
2913 		spin_unlock(&ifp->lock);
2914 		read_unlock_bh(&idev->lock);
2915 
2916 		addrconf_dad_completed(ifp);
2917 		return;
2918 	}
2919 
2920 	if (!(idev->if_flags & IF_READY)) {
2921 		spin_unlock(&ifp->lock);
2922 		read_unlock_bh(&idev->lock);
2923 		/*
2924 		 * If the device is not ready:
2925 		 * - keep it tentative if it is a permanent address.
2926 		 * - otherwise, kill it.
2927 		 */
2928 		in6_ifa_hold(ifp);
2929 		addrconf_dad_stop(ifp, 0);
2930 		return;
2931 	}
2932 
2933 	/*
2934 	 * Optimistic nodes can start receiving
2935 	 * Frames right away
2936 	 */
2937 	if (ifp->flags & IFA_F_OPTIMISTIC)
2938 		ip6_ins_rt(ifp->rt);
2939 
2940 	addrconf_dad_kick(ifp);
2941 out:
2942 	spin_unlock(&ifp->lock);
2943 	read_unlock_bh(&idev->lock);
2944 }
2945 
2946 static void addrconf_dad_timer(unsigned long data)
2947 {
2948 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
2949 	struct inet6_dev *idev = ifp->idev;
2950 	struct in6_addr mcaddr;
2951 
2952 	if (!ifp->probes && addrconf_dad_end(ifp))
2953 		goto out;
2954 
2955 	read_lock(&idev->lock);
2956 	if (idev->dead || !(idev->if_flags & IF_READY)) {
2957 		read_unlock(&idev->lock);
2958 		goto out;
2959 	}
2960 
2961 	spin_lock(&ifp->lock);
2962 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
2963 		spin_unlock(&ifp->lock);
2964 		read_unlock(&idev->lock);
2965 		goto out;
2966 	}
2967 
2968 	if (ifp->probes == 0) {
2969 		/*
2970 		 * DAD was successful
2971 		 */
2972 
2973 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
2974 		spin_unlock(&ifp->lock);
2975 		read_unlock(&idev->lock);
2976 
2977 		addrconf_dad_completed(ifp);
2978 
2979 		goto out;
2980 	}
2981 
2982 	ifp->probes--;
2983 	addrconf_mod_timer(ifp, AC_DAD, ifp->idev->nd_parms->retrans_time);
2984 	spin_unlock(&ifp->lock);
2985 	read_unlock(&idev->lock);
2986 
2987 	/* send a neighbour solicitation for our addr */
2988 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
2989 	ndisc_send_ns(ifp->idev->dev, NULL, &ifp->addr, &mcaddr, &in6addr_any);
2990 out:
2991 	in6_ifa_put(ifp);
2992 }
2993 
2994 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
2995 {
2996 	struct net_device *dev = ifp->idev->dev;
2997 
2998 	/*
2999 	 *	Configure the address for reception. Now it is valid.
3000 	 */
3001 
3002 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
3003 
3004 	/* If added prefix is link local and we are prepared to process
3005 	   router advertisements, start sending router solicitations.
3006 	 */
3007 
3008 	if (((ifp->idev->cnf.accept_ra == 1 && !ifp->idev->cnf.forwarding) ||
3009 	     ifp->idev->cnf.accept_ra == 2) &&
3010 	    ifp->idev->cnf.rtr_solicits > 0 &&
3011 	    (dev->flags&IFF_LOOPBACK) == 0 &&
3012 	    (ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL)) {
3013 		/*
3014 		 *	If a host as already performed a random delay
3015 		 *	[...] as part of DAD [...] there is no need
3016 		 *	to delay again before sending the first RS
3017 		 */
3018 		ndisc_send_rs(ifp->idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
3019 
3020 		spin_lock_bh(&ifp->lock);
3021 		ifp->probes = 1;
3022 		ifp->idev->if_flags |= IF_RS_SENT;
3023 		addrconf_mod_timer(ifp, AC_RS, ifp->idev->cnf.rtr_solicit_interval);
3024 		spin_unlock_bh(&ifp->lock);
3025 	}
3026 }
3027 
3028 static void addrconf_dad_run(struct inet6_dev *idev)
3029 {
3030 	struct inet6_ifaddr *ifp;
3031 
3032 	read_lock_bh(&idev->lock);
3033 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3034 		spin_lock(&ifp->lock);
3035 		if (ifp->flags & IFA_F_TENTATIVE &&
3036 		    ifp->state == INET6_IFADDR_STATE_DAD)
3037 			addrconf_dad_kick(ifp);
3038 		spin_unlock(&ifp->lock);
3039 	}
3040 	read_unlock_bh(&idev->lock);
3041 }
3042 
3043 #ifdef CONFIG_PROC_FS
3044 struct if6_iter_state {
3045 	struct seq_net_private p;
3046 	int bucket;
3047 	int offset;
3048 };
3049 
3050 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
3051 {
3052 	struct inet6_ifaddr *ifa = NULL;
3053 	struct if6_iter_state *state = seq->private;
3054 	struct net *net = seq_file_net(seq);
3055 	int p = 0;
3056 
3057 	/* initial bucket if pos is 0 */
3058 	if (pos == 0) {
3059 		state->bucket = 0;
3060 		state->offset = 0;
3061 	}
3062 
3063 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
3064 		struct hlist_node *n;
3065 		hlist_for_each_entry_rcu_bh(ifa, n, &inet6_addr_lst[state->bucket],
3066 					 addr_lst) {
3067 			/* sync with offset */
3068 			if (p < state->offset) {
3069 				p++;
3070 				continue;
3071 			}
3072 			state->offset++;
3073 			if (net_eq(dev_net(ifa->idev->dev), net))
3074 				return ifa;
3075 		}
3076 
3077 		/* prepare for next bucket */
3078 		state->offset = 0;
3079 		p = 0;
3080 	}
3081 	return NULL;
3082 }
3083 
3084 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
3085 					 struct inet6_ifaddr *ifa)
3086 {
3087 	struct if6_iter_state *state = seq->private;
3088 	struct net *net = seq_file_net(seq);
3089 	struct hlist_node *n = &ifa->addr_lst;
3090 
3091 	hlist_for_each_entry_continue_rcu_bh(ifa, n, addr_lst) {
3092 		state->offset++;
3093 		if (net_eq(dev_net(ifa->idev->dev), net))
3094 			return ifa;
3095 	}
3096 
3097 	while (++state->bucket < IN6_ADDR_HSIZE) {
3098 		state->offset = 0;
3099 		hlist_for_each_entry_rcu_bh(ifa, n,
3100 				     &inet6_addr_lst[state->bucket], addr_lst) {
3101 			state->offset++;
3102 			if (net_eq(dev_net(ifa->idev->dev), net))
3103 				return ifa;
3104 		}
3105 	}
3106 
3107 	return NULL;
3108 }
3109 
3110 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
3111 	__acquires(rcu_bh)
3112 {
3113 	rcu_read_lock_bh();
3114 	return if6_get_first(seq, *pos);
3115 }
3116 
3117 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3118 {
3119 	struct inet6_ifaddr *ifa;
3120 
3121 	ifa = if6_get_next(seq, v);
3122 	++*pos;
3123 	return ifa;
3124 }
3125 
3126 static void if6_seq_stop(struct seq_file *seq, void *v)
3127 	__releases(rcu_bh)
3128 {
3129 	rcu_read_unlock_bh();
3130 }
3131 
3132 static int if6_seq_show(struct seq_file *seq, void *v)
3133 {
3134 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
3135 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
3136 		   &ifp->addr,
3137 		   ifp->idev->dev->ifindex,
3138 		   ifp->prefix_len,
3139 		   ifp->scope,
3140 		   ifp->flags,
3141 		   ifp->idev->dev->name);
3142 	return 0;
3143 }
3144 
3145 static const struct seq_operations if6_seq_ops = {
3146 	.start	= if6_seq_start,
3147 	.next	= if6_seq_next,
3148 	.show	= if6_seq_show,
3149 	.stop	= if6_seq_stop,
3150 };
3151 
3152 static int if6_seq_open(struct inode *inode, struct file *file)
3153 {
3154 	return seq_open_net(inode, file, &if6_seq_ops,
3155 			    sizeof(struct if6_iter_state));
3156 }
3157 
3158 static const struct file_operations if6_fops = {
3159 	.owner		= THIS_MODULE,
3160 	.open		= if6_seq_open,
3161 	.read		= seq_read,
3162 	.llseek		= seq_lseek,
3163 	.release	= seq_release_net,
3164 };
3165 
3166 static int __net_init if6_proc_net_init(struct net *net)
3167 {
3168 	if (!proc_net_fops_create(net, "if_inet6", S_IRUGO, &if6_fops))
3169 		return -ENOMEM;
3170 	return 0;
3171 }
3172 
3173 static void __net_exit if6_proc_net_exit(struct net *net)
3174 {
3175        proc_net_remove(net, "if_inet6");
3176 }
3177 
3178 static struct pernet_operations if6_proc_net_ops = {
3179        .init = if6_proc_net_init,
3180        .exit = if6_proc_net_exit,
3181 };
3182 
3183 int __init if6_proc_init(void)
3184 {
3185 	return register_pernet_subsys(&if6_proc_net_ops);
3186 }
3187 
3188 void if6_proc_exit(void)
3189 {
3190 	unregister_pernet_subsys(&if6_proc_net_ops);
3191 }
3192 #endif	/* CONFIG_PROC_FS */
3193 
3194 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
3195 /* Check if address is a home address configured on any interface. */
3196 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
3197 {
3198 	int ret = 0;
3199 	struct inet6_ifaddr *ifp = NULL;
3200 	struct hlist_node *n;
3201 	unsigned int hash = inet6_addr_hash(addr);
3202 
3203 	rcu_read_lock_bh();
3204 	hlist_for_each_entry_rcu_bh(ifp, n, &inet6_addr_lst[hash], addr_lst) {
3205 		if (!net_eq(dev_net(ifp->idev->dev), net))
3206 			continue;
3207 		if (ipv6_addr_equal(&ifp->addr, addr) &&
3208 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
3209 			ret = 1;
3210 			break;
3211 		}
3212 	}
3213 	rcu_read_unlock_bh();
3214 	return ret;
3215 }
3216 #endif
3217 
3218 /*
3219  *	Periodic address status verification
3220  */
3221 
3222 static void addrconf_verify(unsigned long foo)
3223 {
3224 	unsigned long now, next, next_sec, next_sched;
3225 	struct inet6_ifaddr *ifp;
3226 	struct hlist_node *node;
3227 	int i;
3228 
3229 	rcu_read_lock_bh();
3230 	spin_lock(&addrconf_verify_lock);
3231 	now = jiffies;
3232 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
3233 
3234 	del_timer(&addr_chk_timer);
3235 
3236 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3237 restart:
3238 		hlist_for_each_entry_rcu_bh(ifp, node,
3239 					 &inet6_addr_lst[i], addr_lst) {
3240 			unsigned long age;
3241 
3242 			if (ifp->flags & IFA_F_PERMANENT)
3243 				continue;
3244 
3245 			spin_lock(&ifp->lock);
3246 			/* We try to batch several events at once. */
3247 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
3248 
3249 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
3250 			    age >= ifp->valid_lft) {
3251 				spin_unlock(&ifp->lock);
3252 				in6_ifa_hold(ifp);
3253 				ipv6_del_addr(ifp);
3254 				goto restart;
3255 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
3256 				spin_unlock(&ifp->lock);
3257 				continue;
3258 			} else if (age >= ifp->prefered_lft) {
3259 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
3260 				int deprecate = 0;
3261 
3262 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
3263 					deprecate = 1;
3264 					ifp->flags |= IFA_F_DEPRECATED;
3265 				}
3266 
3267 				if (time_before(ifp->tstamp + ifp->valid_lft * HZ, next))
3268 					next = ifp->tstamp + ifp->valid_lft * HZ;
3269 
3270 				spin_unlock(&ifp->lock);
3271 
3272 				if (deprecate) {
3273 					in6_ifa_hold(ifp);
3274 
3275 					ipv6_ifa_notify(0, ifp);
3276 					in6_ifa_put(ifp);
3277 					goto restart;
3278 				}
3279 #ifdef CONFIG_IPV6_PRIVACY
3280 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
3281 				   !(ifp->flags&IFA_F_TENTATIVE)) {
3282 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
3283 					ifp->idev->cnf.dad_transmits *
3284 					ifp->idev->nd_parms->retrans_time / HZ;
3285 
3286 				if (age >= ifp->prefered_lft - regen_advance) {
3287 					struct inet6_ifaddr *ifpub = ifp->ifpub;
3288 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3289 						next = ifp->tstamp + ifp->prefered_lft * HZ;
3290 					if (!ifp->regen_count && ifpub) {
3291 						ifp->regen_count++;
3292 						in6_ifa_hold(ifp);
3293 						in6_ifa_hold(ifpub);
3294 						spin_unlock(&ifp->lock);
3295 
3296 						spin_lock(&ifpub->lock);
3297 						ifpub->regen_count = 0;
3298 						spin_unlock(&ifpub->lock);
3299 						ipv6_create_tempaddr(ifpub, ifp);
3300 						in6_ifa_put(ifpub);
3301 						in6_ifa_put(ifp);
3302 						goto restart;
3303 					}
3304 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
3305 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
3306 				spin_unlock(&ifp->lock);
3307 #endif
3308 			} else {
3309 				/* ifp->prefered_lft <= ifp->valid_lft */
3310 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3311 					next = ifp->tstamp + ifp->prefered_lft * HZ;
3312 				spin_unlock(&ifp->lock);
3313 			}
3314 		}
3315 	}
3316 
3317 	next_sec = round_jiffies_up(next);
3318 	next_sched = next;
3319 
3320 	/* If rounded timeout is accurate enough, accept it. */
3321 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
3322 		next_sched = next_sec;
3323 
3324 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
3325 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
3326 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
3327 
3328 	ADBG((KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
3329 	      now, next, next_sec, next_sched));
3330 
3331 	addr_chk_timer.expires = next_sched;
3332 	add_timer(&addr_chk_timer);
3333 	spin_unlock(&addrconf_verify_lock);
3334 	rcu_read_unlock_bh();
3335 }
3336 
3337 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local)
3338 {
3339 	struct in6_addr *pfx = NULL;
3340 
3341 	if (addr)
3342 		pfx = nla_data(addr);
3343 
3344 	if (local) {
3345 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
3346 			pfx = NULL;
3347 		else
3348 			pfx = nla_data(local);
3349 	}
3350 
3351 	return pfx;
3352 }
3353 
3354 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
3355 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
3356 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
3357 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
3358 };
3359 
3360 static int
3361 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
3362 {
3363 	struct net *net = sock_net(skb->sk);
3364 	struct ifaddrmsg *ifm;
3365 	struct nlattr *tb[IFA_MAX+1];
3366 	struct in6_addr *pfx;
3367 	int err;
3368 
3369 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3370 	if (err < 0)
3371 		return err;
3372 
3373 	ifm = nlmsg_data(nlh);
3374 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3375 	if (pfx == NULL)
3376 		return -EINVAL;
3377 
3378 	return inet6_addr_del(net, ifm->ifa_index, pfx, ifm->ifa_prefixlen);
3379 }
3380 
3381 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u8 ifa_flags,
3382 			     u32 prefered_lft, u32 valid_lft)
3383 {
3384 	u32 flags;
3385 	clock_t expires;
3386 	unsigned long timeout;
3387 
3388 	if (!valid_lft || (prefered_lft > valid_lft))
3389 		return -EINVAL;
3390 
3391 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
3392 	if (addrconf_finite_timeout(timeout)) {
3393 		expires = jiffies_to_clock_t(timeout * HZ);
3394 		valid_lft = timeout;
3395 		flags = RTF_EXPIRES;
3396 	} else {
3397 		expires = 0;
3398 		flags = 0;
3399 		ifa_flags |= IFA_F_PERMANENT;
3400 	}
3401 
3402 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
3403 	if (addrconf_finite_timeout(timeout)) {
3404 		if (timeout == 0)
3405 			ifa_flags |= IFA_F_DEPRECATED;
3406 		prefered_lft = timeout;
3407 	}
3408 
3409 	spin_lock_bh(&ifp->lock);
3410 	ifp->flags = (ifp->flags & ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD | IFA_F_HOMEADDRESS)) | ifa_flags;
3411 	ifp->tstamp = jiffies;
3412 	ifp->valid_lft = valid_lft;
3413 	ifp->prefered_lft = prefered_lft;
3414 
3415 	spin_unlock_bh(&ifp->lock);
3416 	if (!(ifp->flags&IFA_F_TENTATIVE))
3417 		ipv6_ifa_notify(0, ifp);
3418 
3419 	addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
3420 			      expires, flags);
3421 	addrconf_verify(0);
3422 
3423 	return 0;
3424 }
3425 
3426 static int
3427 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
3428 {
3429 	struct net *net = sock_net(skb->sk);
3430 	struct ifaddrmsg *ifm;
3431 	struct nlattr *tb[IFA_MAX+1];
3432 	struct in6_addr *pfx;
3433 	struct inet6_ifaddr *ifa;
3434 	struct net_device *dev;
3435 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
3436 	u8 ifa_flags;
3437 	int err;
3438 
3439 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3440 	if (err < 0)
3441 		return err;
3442 
3443 	ifm = nlmsg_data(nlh);
3444 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3445 	if (pfx == NULL)
3446 		return -EINVAL;
3447 
3448 	if (tb[IFA_CACHEINFO]) {
3449 		struct ifa_cacheinfo *ci;
3450 
3451 		ci = nla_data(tb[IFA_CACHEINFO]);
3452 		valid_lft = ci->ifa_valid;
3453 		preferred_lft = ci->ifa_prefered;
3454 	} else {
3455 		preferred_lft = INFINITY_LIFE_TIME;
3456 		valid_lft = INFINITY_LIFE_TIME;
3457 	}
3458 
3459 	dev =  __dev_get_by_index(net, ifm->ifa_index);
3460 	if (dev == NULL)
3461 		return -ENODEV;
3462 
3463 	/* We ignore other flags so far. */
3464 	ifa_flags = ifm->ifa_flags & (IFA_F_NODAD | IFA_F_HOMEADDRESS);
3465 
3466 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
3467 	if (ifa == NULL) {
3468 		/*
3469 		 * It would be best to check for !NLM_F_CREATE here but
3470 		 * userspace alreay relies on not having to provide this.
3471 		 */
3472 		return inet6_addr_add(net, ifm->ifa_index, pfx,
3473 				      ifm->ifa_prefixlen, ifa_flags,
3474 				      preferred_lft, valid_lft);
3475 	}
3476 
3477 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
3478 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
3479 		err = -EEXIST;
3480 	else
3481 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
3482 
3483 	in6_ifa_put(ifa);
3484 
3485 	return err;
3486 }
3487 
3488 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u8 flags,
3489 			  u8 scope, int ifindex)
3490 {
3491 	struct ifaddrmsg *ifm;
3492 
3493 	ifm = nlmsg_data(nlh);
3494 	ifm->ifa_family = AF_INET6;
3495 	ifm->ifa_prefixlen = prefixlen;
3496 	ifm->ifa_flags = flags;
3497 	ifm->ifa_scope = scope;
3498 	ifm->ifa_index = ifindex;
3499 }
3500 
3501 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
3502 			 unsigned long tstamp, u32 preferred, u32 valid)
3503 {
3504 	struct ifa_cacheinfo ci;
3505 
3506 	ci.cstamp = cstamp_delta(cstamp);
3507 	ci.tstamp = cstamp_delta(tstamp);
3508 	ci.ifa_prefered = preferred;
3509 	ci.ifa_valid = valid;
3510 
3511 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
3512 }
3513 
3514 static inline int rt_scope(int ifa_scope)
3515 {
3516 	if (ifa_scope & IFA_HOST)
3517 		return RT_SCOPE_HOST;
3518 	else if (ifa_scope & IFA_LINK)
3519 		return RT_SCOPE_LINK;
3520 	else if (ifa_scope & IFA_SITE)
3521 		return RT_SCOPE_SITE;
3522 	else
3523 		return RT_SCOPE_UNIVERSE;
3524 }
3525 
3526 static inline int inet6_ifaddr_msgsize(void)
3527 {
3528 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
3529 	       + nla_total_size(16) /* IFA_ADDRESS */
3530 	       + nla_total_size(sizeof(struct ifa_cacheinfo));
3531 }
3532 
3533 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
3534 			     u32 portid, u32 seq, int event, unsigned int flags)
3535 {
3536 	struct nlmsghdr  *nlh;
3537 	u32 preferred, valid;
3538 
3539 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3540 	if (nlh == NULL)
3541 		return -EMSGSIZE;
3542 
3543 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
3544 		      ifa->idev->dev->ifindex);
3545 
3546 	if (!(ifa->flags&IFA_F_PERMANENT)) {
3547 		preferred = ifa->prefered_lft;
3548 		valid = ifa->valid_lft;
3549 		if (preferred != INFINITY_LIFE_TIME) {
3550 			long tval = (jiffies - ifa->tstamp)/HZ;
3551 			if (preferred > tval)
3552 				preferred -= tval;
3553 			else
3554 				preferred = 0;
3555 			if (valid != INFINITY_LIFE_TIME) {
3556 				if (valid > tval)
3557 					valid -= tval;
3558 				else
3559 					valid = 0;
3560 			}
3561 		}
3562 	} else {
3563 		preferred = INFINITY_LIFE_TIME;
3564 		valid = INFINITY_LIFE_TIME;
3565 	}
3566 
3567 	if (nla_put(skb, IFA_ADDRESS, 16, &ifa->addr) < 0 ||
3568 	    put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0) {
3569 		nlmsg_cancel(skb, nlh);
3570 		return -EMSGSIZE;
3571 	}
3572 
3573 	return nlmsg_end(skb, nlh);
3574 }
3575 
3576 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
3577 				u32 portid, u32 seq, int event, u16 flags)
3578 {
3579 	struct nlmsghdr  *nlh;
3580 	u8 scope = RT_SCOPE_UNIVERSE;
3581 	int ifindex = ifmca->idev->dev->ifindex;
3582 
3583 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
3584 		scope = RT_SCOPE_SITE;
3585 
3586 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3587 	if (nlh == NULL)
3588 		return -EMSGSIZE;
3589 
3590 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3591 	if (nla_put(skb, IFA_MULTICAST, 16, &ifmca->mca_addr) < 0 ||
3592 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
3593 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3594 		nlmsg_cancel(skb, nlh);
3595 		return -EMSGSIZE;
3596 	}
3597 
3598 	return nlmsg_end(skb, nlh);
3599 }
3600 
3601 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
3602 				u32 portid, u32 seq, int event, unsigned int flags)
3603 {
3604 	struct nlmsghdr  *nlh;
3605 	u8 scope = RT_SCOPE_UNIVERSE;
3606 	int ifindex = ifaca->aca_idev->dev->ifindex;
3607 
3608 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
3609 		scope = RT_SCOPE_SITE;
3610 
3611 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3612 	if (nlh == NULL)
3613 		return -EMSGSIZE;
3614 
3615 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3616 	if (nla_put(skb, IFA_ANYCAST, 16, &ifaca->aca_addr) < 0 ||
3617 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
3618 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3619 		nlmsg_cancel(skb, nlh);
3620 		return -EMSGSIZE;
3621 	}
3622 
3623 	return nlmsg_end(skb, nlh);
3624 }
3625 
3626 enum addr_type_t {
3627 	UNICAST_ADDR,
3628 	MULTICAST_ADDR,
3629 	ANYCAST_ADDR,
3630 };
3631 
3632 /* called with rcu_read_lock() */
3633 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
3634 			  struct netlink_callback *cb, enum addr_type_t type,
3635 			  int s_ip_idx, int *p_ip_idx)
3636 {
3637 	struct ifmcaddr6 *ifmca;
3638 	struct ifacaddr6 *ifaca;
3639 	int err = 1;
3640 	int ip_idx = *p_ip_idx;
3641 
3642 	read_lock_bh(&idev->lock);
3643 	switch (type) {
3644 	case UNICAST_ADDR: {
3645 		struct inet6_ifaddr *ifa;
3646 
3647 		/* unicast address incl. temp addr */
3648 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
3649 			if (++ip_idx < s_ip_idx)
3650 				continue;
3651 			err = inet6_fill_ifaddr(skb, ifa,
3652 						NETLINK_CB(cb->skb).portid,
3653 						cb->nlh->nlmsg_seq,
3654 						RTM_NEWADDR,
3655 						NLM_F_MULTI);
3656 			if (err <= 0)
3657 				break;
3658 		}
3659 		break;
3660 	}
3661 	case MULTICAST_ADDR:
3662 		/* multicast address */
3663 		for (ifmca = idev->mc_list; ifmca;
3664 		     ifmca = ifmca->next, ip_idx++) {
3665 			if (ip_idx < s_ip_idx)
3666 				continue;
3667 			err = inet6_fill_ifmcaddr(skb, ifmca,
3668 						  NETLINK_CB(cb->skb).portid,
3669 						  cb->nlh->nlmsg_seq,
3670 						  RTM_GETMULTICAST,
3671 						  NLM_F_MULTI);
3672 			if (err <= 0)
3673 				break;
3674 		}
3675 		break;
3676 	case ANYCAST_ADDR:
3677 		/* anycast address */
3678 		for (ifaca = idev->ac_list; ifaca;
3679 		     ifaca = ifaca->aca_next, ip_idx++) {
3680 			if (ip_idx < s_ip_idx)
3681 				continue;
3682 			err = inet6_fill_ifacaddr(skb, ifaca,
3683 						  NETLINK_CB(cb->skb).portid,
3684 						  cb->nlh->nlmsg_seq,
3685 						  RTM_GETANYCAST,
3686 						  NLM_F_MULTI);
3687 			if (err <= 0)
3688 				break;
3689 		}
3690 		break;
3691 	default:
3692 		break;
3693 	}
3694 	read_unlock_bh(&idev->lock);
3695 	*p_ip_idx = ip_idx;
3696 	return err;
3697 }
3698 
3699 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
3700 			   enum addr_type_t type)
3701 {
3702 	struct net *net = sock_net(skb->sk);
3703 	int h, s_h;
3704 	int idx, ip_idx;
3705 	int s_idx, s_ip_idx;
3706 	struct net_device *dev;
3707 	struct inet6_dev *idev;
3708 	struct hlist_head *head;
3709 	struct hlist_node *node;
3710 
3711 	s_h = cb->args[0];
3712 	s_idx = idx = cb->args[1];
3713 	s_ip_idx = ip_idx = cb->args[2];
3714 
3715 	rcu_read_lock();
3716 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
3717 		idx = 0;
3718 		head = &net->dev_index_head[h];
3719 		hlist_for_each_entry_rcu(dev, node, head, index_hlist) {
3720 			if (idx < s_idx)
3721 				goto cont;
3722 			if (h > s_h || idx > s_idx)
3723 				s_ip_idx = 0;
3724 			ip_idx = 0;
3725 			idev = __in6_dev_get(dev);
3726 			if (!idev)
3727 				goto cont;
3728 
3729 			if (in6_dump_addrs(idev, skb, cb, type,
3730 					   s_ip_idx, &ip_idx) <= 0)
3731 				goto done;
3732 cont:
3733 			idx++;
3734 		}
3735 	}
3736 done:
3737 	rcu_read_unlock();
3738 	cb->args[0] = h;
3739 	cb->args[1] = idx;
3740 	cb->args[2] = ip_idx;
3741 
3742 	return skb->len;
3743 }
3744 
3745 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
3746 {
3747 	enum addr_type_t type = UNICAST_ADDR;
3748 
3749 	return inet6_dump_addr(skb, cb, type);
3750 }
3751 
3752 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
3753 {
3754 	enum addr_type_t type = MULTICAST_ADDR;
3755 
3756 	return inet6_dump_addr(skb, cb, type);
3757 }
3758 
3759 
3760 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
3761 {
3762 	enum addr_type_t type = ANYCAST_ADDR;
3763 
3764 	return inet6_dump_addr(skb, cb, type);
3765 }
3766 
3767 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
3768 			     void *arg)
3769 {
3770 	struct net *net = sock_net(in_skb->sk);
3771 	struct ifaddrmsg *ifm;
3772 	struct nlattr *tb[IFA_MAX+1];
3773 	struct in6_addr *addr = NULL;
3774 	struct net_device *dev = NULL;
3775 	struct inet6_ifaddr *ifa;
3776 	struct sk_buff *skb;
3777 	int err;
3778 
3779 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3780 	if (err < 0)
3781 		goto errout;
3782 
3783 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3784 	if (addr == NULL) {
3785 		err = -EINVAL;
3786 		goto errout;
3787 	}
3788 
3789 	ifm = nlmsg_data(nlh);
3790 	if (ifm->ifa_index)
3791 		dev = __dev_get_by_index(net, ifm->ifa_index);
3792 
3793 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
3794 	if (!ifa) {
3795 		err = -EADDRNOTAVAIL;
3796 		goto errout;
3797 	}
3798 
3799 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
3800 	if (!skb) {
3801 		err = -ENOBUFS;
3802 		goto errout_ifa;
3803 	}
3804 
3805 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
3806 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
3807 	if (err < 0) {
3808 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
3809 		WARN_ON(err == -EMSGSIZE);
3810 		kfree_skb(skb);
3811 		goto errout_ifa;
3812 	}
3813 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3814 errout_ifa:
3815 	in6_ifa_put(ifa);
3816 errout:
3817 	return err;
3818 }
3819 
3820 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
3821 {
3822 	struct sk_buff *skb;
3823 	struct net *net = dev_net(ifa->idev->dev);
3824 	int err = -ENOBUFS;
3825 
3826 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
3827 	if (skb == NULL)
3828 		goto errout;
3829 
3830 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
3831 	if (err < 0) {
3832 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
3833 		WARN_ON(err == -EMSGSIZE);
3834 		kfree_skb(skb);
3835 		goto errout;
3836 	}
3837 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
3838 	return;
3839 errout:
3840 	if (err < 0)
3841 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
3842 }
3843 
3844 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
3845 				__s32 *array, int bytes)
3846 {
3847 	BUG_ON(bytes < (DEVCONF_MAX * 4));
3848 
3849 	memset(array, 0, bytes);
3850 	array[DEVCONF_FORWARDING] = cnf->forwarding;
3851 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
3852 	array[DEVCONF_MTU6] = cnf->mtu6;
3853 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
3854 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
3855 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
3856 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
3857 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
3858 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
3859 		jiffies_to_msecs(cnf->rtr_solicit_interval);
3860 	array[DEVCONF_RTR_SOLICIT_DELAY] =
3861 		jiffies_to_msecs(cnf->rtr_solicit_delay);
3862 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
3863 #ifdef CONFIG_IPV6_PRIVACY
3864 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
3865 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
3866 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
3867 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
3868 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
3869 #endif
3870 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
3871 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
3872 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
3873 #ifdef CONFIG_IPV6_ROUTER_PREF
3874 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
3875 	array[DEVCONF_RTR_PROBE_INTERVAL] =
3876 		jiffies_to_msecs(cnf->rtr_probe_interval);
3877 #ifdef CONFIG_IPV6_ROUTE_INFO
3878 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
3879 #endif
3880 #endif
3881 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
3882 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
3883 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3884 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
3885 #endif
3886 #ifdef CONFIG_IPV6_MROUTE
3887 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
3888 #endif
3889 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
3890 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
3891 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
3892 }
3893 
3894 static inline size_t inet6_ifla6_size(void)
3895 {
3896 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
3897 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
3898 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
3899 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
3900 	     + nla_total_size(ICMP6_MIB_MAX * 8); /* IFLA_INET6_ICMP6STATS */
3901 }
3902 
3903 static inline size_t inet6_if_nlmsg_size(void)
3904 {
3905 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
3906 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
3907 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
3908 	       + nla_total_size(4) /* IFLA_MTU */
3909 	       + nla_total_size(4) /* IFLA_LINK */
3910 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
3911 }
3912 
3913 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
3914 				      int items, int bytes)
3915 {
3916 	int i;
3917 	int pad = bytes - sizeof(u64) * items;
3918 	BUG_ON(pad < 0);
3919 
3920 	/* Use put_unaligned() because stats may not be aligned for u64. */
3921 	put_unaligned(items, &stats[0]);
3922 	for (i = 1; i < items; i++)
3923 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
3924 
3925 	memset(&stats[items], 0, pad);
3926 }
3927 
3928 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu **mib,
3929 				      int items, int bytes, size_t syncpoff)
3930 {
3931 	int i;
3932 	int pad = bytes - sizeof(u64) * items;
3933 	BUG_ON(pad < 0);
3934 
3935 	/* Use put_unaligned() because stats may not be aligned for u64. */
3936 	put_unaligned(items, &stats[0]);
3937 	for (i = 1; i < items; i++)
3938 		put_unaligned(snmp_fold_field64(mib, i, syncpoff), &stats[i]);
3939 
3940 	memset(&stats[items], 0, pad);
3941 }
3942 
3943 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
3944 			     int bytes)
3945 {
3946 	switch (attrtype) {
3947 	case IFLA_INET6_STATS:
3948 		__snmp6_fill_stats64(stats, (void __percpu **)idev->stats.ipv6,
3949 				     IPSTATS_MIB_MAX, bytes, offsetof(struct ipstats_mib, syncp));
3950 		break;
3951 	case IFLA_INET6_ICMP6STATS:
3952 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, ICMP6_MIB_MAX, bytes);
3953 		break;
3954 	}
3955 }
3956 
3957 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev)
3958 {
3959 	struct nlattr *nla;
3960 	struct ifla_cacheinfo ci;
3961 
3962 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
3963 		goto nla_put_failure;
3964 	ci.max_reasm_len = IPV6_MAXPLEN;
3965 	ci.tstamp = cstamp_delta(idev->tstamp);
3966 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
3967 	ci.retrans_time = jiffies_to_msecs(idev->nd_parms->retrans_time);
3968 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
3969 		goto nla_put_failure;
3970 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
3971 	if (nla == NULL)
3972 		goto nla_put_failure;
3973 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
3974 
3975 	/* XXX - MC not implemented */
3976 
3977 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
3978 	if (nla == NULL)
3979 		goto nla_put_failure;
3980 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
3981 
3982 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
3983 	if (nla == NULL)
3984 		goto nla_put_failure;
3985 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
3986 
3987 	return 0;
3988 
3989 nla_put_failure:
3990 	return -EMSGSIZE;
3991 }
3992 
3993 static size_t inet6_get_link_af_size(const struct net_device *dev)
3994 {
3995 	if (!__in6_dev_get(dev))
3996 		return 0;
3997 
3998 	return inet6_ifla6_size();
3999 }
4000 
4001 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
4002 {
4003 	struct inet6_dev *idev = __in6_dev_get(dev);
4004 
4005 	if (!idev)
4006 		return -ENODATA;
4007 
4008 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4009 		return -EMSGSIZE;
4010 
4011 	return 0;
4012 }
4013 
4014 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
4015 			     u32 portid, u32 seq, int event, unsigned int flags)
4016 {
4017 	struct net_device *dev = idev->dev;
4018 	struct ifinfomsg *hdr;
4019 	struct nlmsghdr *nlh;
4020 	void *protoinfo;
4021 
4022 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
4023 	if (nlh == NULL)
4024 		return -EMSGSIZE;
4025 
4026 	hdr = nlmsg_data(nlh);
4027 	hdr->ifi_family = AF_INET6;
4028 	hdr->__ifi_pad = 0;
4029 	hdr->ifi_type = dev->type;
4030 	hdr->ifi_index = dev->ifindex;
4031 	hdr->ifi_flags = dev_get_flags(dev);
4032 	hdr->ifi_change = 0;
4033 
4034 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
4035 	    (dev->addr_len &&
4036 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
4037 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
4038 	    (dev->ifindex != dev->iflink &&
4039 	     nla_put_u32(skb, IFLA_LINK, dev->iflink)))
4040 		goto nla_put_failure;
4041 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
4042 	if (protoinfo == NULL)
4043 		goto nla_put_failure;
4044 
4045 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4046 		goto nla_put_failure;
4047 
4048 	nla_nest_end(skb, protoinfo);
4049 	return nlmsg_end(skb, nlh);
4050 
4051 nla_put_failure:
4052 	nlmsg_cancel(skb, nlh);
4053 	return -EMSGSIZE;
4054 }
4055 
4056 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
4057 {
4058 	struct net *net = sock_net(skb->sk);
4059 	int h, s_h;
4060 	int idx = 0, s_idx;
4061 	struct net_device *dev;
4062 	struct inet6_dev *idev;
4063 	struct hlist_head *head;
4064 	struct hlist_node *node;
4065 
4066 	s_h = cb->args[0];
4067 	s_idx = cb->args[1];
4068 
4069 	rcu_read_lock();
4070 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4071 		idx = 0;
4072 		head = &net->dev_index_head[h];
4073 		hlist_for_each_entry_rcu(dev, node, head, index_hlist) {
4074 			if (idx < s_idx)
4075 				goto cont;
4076 			idev = __in6_dev_get(dev);
4077 			if (!idev)
4078 				goto cont;
4079 			if (inet6_fill_ifinfo(skb, idev,
4080 					      NETLINK_CB(cb->skb).portid,
4081 					      cb->nlh->nlmsg_seq,
4082 					      RTM_NEWLINK, NLM_F_MULTI) <= 0)
4083 				goto out;
4084 cont:
4085 			idx++;
4086 		}
4087 	}
4088 out:
4089 	rcu_read_unlock();
4090 	cb->args[1] = idx;
4091 	cb->args[0] = h;
4092 
4093 	return skb->len;
4094 }
4095 
4096 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
4097 {
4098 	struct sk_buff *skb;
4099 	struct net *net = dev_net(idev->dev);
4100 	int err = -ENOBUFS;
4101 
4102 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
4103 	if (skb == NULL)
4104 		goto errout;
4105 
4106 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
4107 	if (err < 0) {
4108 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
4109 		WARN_ON(err == -EMSGSIZE);
4110 		kfree_skb(skb);
4111 		goto errout;
4112 	}
4113 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
4114 	return;
4115 errout:
4116 	if (err < 0)
4117 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
4118 }
4119 
4120 static inline size_t inet6_prefix_nlmsg_size(void)
4121 {
4122 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
4123 	       + nla_total_size(sizeof(struct in6_addr))
4124 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
4125 }
4126 
4127 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
4128 			     struct prefix_info *pinfo, u32 portid, u32 seq,
4129 			     int event, unsigned int flags)
4130 {
4131 	struct prefixmsg *pmsg;
4132 	struct nlmsghdr *nlh;
4133 	struct prefix_cacheinfo	ci;
4134 
4135 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
4136 	if (nlh == NULL)
4137 		return -EMSGSIZE;
4138 
4139 	pmsg = nlmsg_data(nlh);
4140 	pmsg->prefix_family = AF_INET6;
4141 	pmsg->prefix_pad1 = 0;
4142 	pmsg->prefix_pad2 = 0;
4143 	pmsg->prefix_ifindex = idev->dev->ifindex;
4144 	pmsg->prefix_len = pinfo->prefix_len;
4145 	pmsg->prefix_type = pinfo->type;
4146 	pmsg->prefix_pad3 = 0;
4147 	pmsg->prefix_flags = 0;
4148 	if (pinfo->onlink)
4149 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
4150 	if (pinfo->autoconf)
4151 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
4152 
4153 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
4154 		goto nla_put_failure;
4155 	ci.preferred_time = ntohl(pinfo->prefered);
4156 	ci.valid_time = ntohl(pinfo->valid);
4157 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
4158 		goto nla_put_failure;
4159 	return nlmsg_end(skb, nlh);
4160 
4161 nla_put_failure:
4162 	nlmsg_cancel(skb, nlh);
4163 	return -EMSGSIZE;
4164 }
4165 
4166 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
4167 			 struct prefix_info *pinfo)
4168 {
4169 	struct sk_buff *skb;
4170 	struct net *net = dev_net(idev->dev);
4171 	int err = -ENOBUFS;
4172 
4173 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
4174 	if (skb == NULL)
4175 		goto errout;
4176 
4177 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
4178 	if (err < 0) {
4179 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
4180 		WARN_ON(err == -EMSGSIZE);
4181 		kfree_skb(skb);
4182 		goto errout;
4183 	}
4184 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
4185 	return;
4186 errout:
4187 	if (err < 0)
4188 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
4189 }
4190 
4191 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4192 {
4193 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
4194 
4195 	switch (event) {
4196 	case RTM_NEWADDR:
4197 		/*
4198 		 * If the address was optimistic
4199 		 * we inserted the route at the start of
4200 		 * our DAD process, so we don't need
4201 		 * to do it again
4202 		 */
4203 		if (!(ifp->rt->rt6i_node))
4204 			ip6_ins_rt(ifp->rt);
4205 		if (ifp->idev->cnf.forwarding)
4206 			addrconf_join_anycast(ifp);
4207 		break;
4208 	case RTM_DELADDR:
4209 		if (ifp->idev->cnf.forwarding)
4210 			addrconf_leave_anycast(ifp);
4211 		addrconf_leave_solict(ifp->idev, &ifp->addr);
4212 		dst_hold(&ifp->rt->dst);
4213 
4214 		if (ip6_del_rt(ifp->rt))
4215 			dst_free(&ifp->rt->dst);
4216 		break;
4217 	}
4218 }
4219 
4220 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4221 {
4222 	rcu_read_lock_bh();
4223 	if (likely(ifp->idev->dead == 0))
4224 		__ipv6_ifa_notify(event, ifp);
4225 	rcu_read_unlock_bh();
4226 }
4227 
4228 #ifdef CONFIG_SYSCTL
4229 
4230 static
4231 int addrconf_sysctl_forward(ctl_table *ctl, int write,
4232 			   void __user *buffer, size_t *lenp, loff_t *ppos)
4233 {
4234 	int *valp = ctl->data;
4235 	int val = *valp;
4236 	loff_t pos = *ppos;
4237 	ctl_table lctl;
4238 	int ret;
4239 
4240 	/*
4241 	 * ctl->data points to idev->cnf.forwarding, we should
4242 	 * not modify it until we get the rtnl lock.
4243 	 */
4244 	lctl = *ctl;
4245 	lctl.data = &val;
4246 
4247 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4248 
4249 	if (write)
4250 		ret = addrconf_fixup_forwarding(ctl, valp, val);
4251 	if (ret)
4252 		*ppos = pos;
4253 	return ret;
4254 }
4255 
4256 static void dev_disable_change(struct inet6_dev *idev)
4257 {
4258 	if (!idev || !idev->dev)
4259 		return;
4260 
4261 	if (idev->cnf.disable_ipv6)
4262 		addrconf_notify(NULL, NETDEV_DOWN, idev->dev);
4263 	else
4264 		addrconf_notify(NULL, NETDEV_UP, idev->dev);
4265 }
4266 
4267 static void addrconf_disable_change(struct net *net, __s32 newf)
4268 {
4269 	struct net_device *dev;
4270 	struct inet6_dev *idev;
4271 
4272 	rcu_read_lock();
4273 	for_each_netdev_rcu(net, dev) {
4274 		idev = __in6_dev_get(dev);
4275 		if (idev) {
4276 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
4277 			idev->cnf.disable_ipv6 = newf;
4278 			if (changed)
4279 				dev_disable_change(idev);
4280 		}
4281 	}
4282 	rcu_read_unlock();
4283 }
4284 
4285 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
4286 {
4287 	struct net *net;
4288 	int old;
4289 
4290 	if (!rtnl_trylock())
4291 		return restart_syscall();
4292 
4293 	net = (struct net *)table->extra2;
4294 	old = *p;
4295 	*p = newf;
4296 
4297 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
4298 		rtnl_unlock();
4299 		return 0;
4300 	}
4301 
4302 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
4303 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
4304 		addrconf_disable_change(net, newf);
4305 	} else if ((!newf) ^ (!old))
4306 		dev_disable_change((struct inet6_dev *)table->extra1);
4307 
4308 	rtnl_unlock();
4309 	return 0;
4310 }
4311 
4312 static
4313 int addrconf_sysctl_disable(ctl_table *ctl, int write,
4314 			    void __user *buffer, size_t *lenp, loff_t *ppos)
4315 {
4316 	int *valp = ctl->data;
4317 	int val = *valp;
4318 	loff_t pos = *ppos;
4319 	ctl_table lctl;
4320 	int ret;
4321 
4322 	/*
4323 	 * ctl->data points to idev->cnf.disable_ipv6, we should
4324 	 * not modify it until we get the rtnl lock.
4325 	 */
4326 	lctl = *ctl;
4327 	lctl.data = &val;
4328 
4329 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4330 
4331 	if (write)
4332 		ret = addrconf_disable_ipv6(ctl, valp, val);
4333 	if (ret)
4334 		*ppos = pos;
4335 	return ret;
4336 }
4337 
4338 static struct addrconf_sysctl_table
4339 {
4340 	struct ctl_table_header *sysctl_header;
4341 	ctl_table addrconf_vars[DEVCONF_MAX+1];
4342 } addrconf_sysctl __read_mostly = {
4343 	.sysctl_header = NULL,
4344 	.addrconf_vars = {
4345 		{
4346 			.procname	= "forwarding",
4347 			.data		= &ipv6_devconf.forwarding,
4348 			.maxlen		= sizeof(int),
4349 			.mode		= 0644,
4350 			.proc_handler	= addrconf_sysctl_forward,
4351 		},
4352 		{
4353 			.procname	= "hop_limit",
4354 			.data		= &ipv6_devconf.hop_limit,
4355 			.maxlen		= sizeof(int),
4356 			.mode		= 0644,
4357 			.proc_handler	= proc_dointvec,
4358 		},
4359 		{
4360 			.procname	= "mtu",
4361 			.data		= &ipv6_devconf.mtu6,
4362 			.maxlen		= sizeof(int),
4363 			.mode		= 0644,
4364 			.proc_handler	= proc_dointvec,
4365 		},
4366 		{
4367 			.procname	= "accept_ra",
4368 			.data		= &ipv6_devconf.accept_ra,
4369 			.maxlen		= sizeof(int),
4370 			.mode		= 0644,
4371 			.proc_handler	= proc_dointvec,
4372 		},
4373 		{
4374 			.procname	= "accept_redirects",
4375 			.data		= &ipv6_devconf.accept_redirects,
4376 			.maxlen		= sizeof(int),
4377 			.mode		= 0644,
4378 			.proc_handler	= proc_dointvec,
4379 		},
4380 		{
4381 			.procname	= "autoconf",
4382 			.data		= &ipv6_devconf.autoconf,
4383 			.maxlen		= sizeof(int),
4384 			.mode		= 0644,
4385 			.proc_handler	= proc_dointvec,
4386 		},
4387 		{
4388 			.procname	= "dad_transmits",
4389 			.data		= &ipv6_devconf.dad_transmits,
4390 			.maxlen		= sizeof(int),
4391 			.mode		= 0644,
4392 			.proc_handler	= proc_dointvec,
4393 		},
4394 		{
4395 			.procname	= "router_solicitations",
4396 			.data		= &ipv6_devconf.rtr_solicits,
4397 			.maxlen		= sizeof(int),
4398 			.mode		= 0644,
4399 			.proc_handler	= proc_dointvec,
4400 		},
4401 		{
4402 			.procname	= "router_solicitation_interval",
4403 			.data		= &ipv6_devconf.rtr_solicit_interval,
4404 			.maxlen		= sizeof(int),
4405 			.mode		= 0644,
4406 			.proc_handler	= proc_dointvec_jiffies,
4407 		},
4408 		{
4409 			.procname	= "router_solicitation_delay",
4410 			.data		= &ipv6_devconf.rtr_solicit_delay,
4411 			.maxlen		= sizeof(int),
4412 			.mode		= 0644,
4413 			.proc_handler	= proc_dointvec_jiffies,
4414 		},
4415 		{
4416 			.procname	= "force_mld_version",
4417 			.data		= &ipv6_devconf.force_mld_version,
4418 			.maxlen		= sizeof(int),
4419 			.mode		= 0644,
4420 			.proc_handler	= proc_dointvec,
4421 		},
4422 #ifdef CONFIG_IPV6_PRIVACY
4423 		{
4424 			.procname	= "use_tempaddr",
4425 			.data		= &ipv6_devconf.use_tempaddr,
4426 			.maxlen		= sizeof(int),
4427 			.mode		= 0644,
4428 			.proc_handler	= proc_dointvec,
4429 		},
4430 		{
4431 			.procname	= "temp_valid_lft",
4432 			.data		= &ipv6_devconf.temp_valid_lft,
4433 			.maxlen		= sizeof(int),
4434 			.mode		= 0644,
4435 			.proc_handler	= proc_dointvec,
4436 		},
4437 		{
4438 			.procname	= "temp_prefered_lft",
4439 			.data		= &ipv6_devconf.temp_prefered_lft,
4440 			.maxlen		= sizeof(int),
4441 			.mode		= 0644,
4442 			.proc_handler	= proc_dointvec,
4443 		},
4444 		{
4445 			.procname	= "regen_max_retry",
4446 			.data		= &ipv6_devconf.regen_max_retry,
4447 			.maxlen		= sizeof(int),
4448 			.mode		= 0644,
4449 			.proc_handler	= proc_dointvec,
4450 		},
4451 		{
4452 			.procname	= "max_desync_factor",
4453 			.data		= &ipv6_devconf.max_desync_factor,
4454 			.maxlen		= sizeof(int),
4455 			.mode		= 0644,
4456 			.proc_handler	= proc_dointvec,
4457 		},
4458 #endif
4459 		{
4460 			.procname	= "max_addresses",
4461 			.data		= &ipv6_devconf.max_addresses,
4462 			.maxlen		= sizeof(int),
4463 			.mode		= 0644,
4464 			.proc_handler	= proc_dointvec,
4465 		},
4466 		{
4467 			.procname	= "accept_ra_defrtr",
4468 			.data		= &ipv6_devconf.accept_ra_defrtr,
4469 			.maxlen		= sizeof(int),
4470 			.mode		= 0644,
4471 			.proc_handler	= proc_dointvec,
4472 		},
4473 		{
4474 			.procname	= "accept_ra_pinfo",
4475 			.data		= &ipv6_devconf.accept_ra_pinfo,
4476 			.maxlen		= sizeof(int),
4477 			.mode		= 0644,
4478 			.proc_handler	= proc_dointvec,
4479 		},
4480 #ifdef CONFIG_IPV6_ROUTER_PREF
4481 		{
4482 			.procname	= "accept_ra_rtr_pref",
4483 			.data		= &ipv6_devconf.accept_ra_rtr_pref,
4484 			.maxlen		= sizeof(int),
4485 			.mode		= 0644,
4486 			.proc_handler	= proc_dointvec,
4487 		},
4488 		{
4489 			.procname	= "router_probe_interval",
4490 			.data		= &ipv6_devconf.rtr_probe_interval,
4491 			.maxlen		= sizeof(int),
4492 			.mode		= 0644,
4493 			.proc_handler	= proc_dointvec_jiffies,
4494 		},
4495 #ifdef CONFIG_IPV6_ROUTE_INFO
4496 		{
4497 			.procname	= "accept_ra_rt_info_max_plen",
4498 			.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
4499 			.maxlen		= sizeof(int),
4500 			.mode		= 0644,
4501 			.proc_handler	= proc_dointvec,
4502 		},
4503 #endif
4504 #endif
4505 		{
4506 			.procname	= "proxy_ndp",
4507 			.data		= &ipv6_devconf.proxy_ndp,
4508 			.maxlen		= sizeof(int),
4509 			.mode		= 0644,
4510 			.proc_handler	= proc_dointvec,
4511 		},
4512 		{
4513 			.procname	= "accept_source_route",
4514 			.data		= &ipv6_devconf.accept_source_route,
4515 			.maxlen		= sizeof(int),
4516 			.mode		= 0644,
4517 			.proc_handler	= proc_dointvec,
4518 		},
4519 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4520 		{
4521 			.procname       = "optimistic_dad",
4522 			.data           = &ipv6_devconf.optimistic_dad,
4523 			.maxlen         = sizeof(int),
4524 			.mode           = 0644,
4525 			.proc_handler   = proc_dointvec,
4526 
4527 		},
4528 #endif
4529 #ifdef CONFIG_IPV6_MROUTE
4530 		{
4531 			.procname	= "mc_forwarding",
4532 			.data		= &ipv6_devconf.mc_forwarding,
4533 			.maxlen		= sizeof(int),
4534 			.mode		= 0444,
4535 			.proc_handler	= proc_dointvec,
4536 		},
4537 #endif
4538 		{
4539 			.procname	= "disable_ipv6",
4540 			.data		= &ipv6_devconf.disable_ipv6,
4541 			.maxlen		= sizeof(int),
4542 			.mode		= 0644,
4543 			.proc_handler	= addrconf_sysctl_disable,
4544 		},
4545 		{
4546 			.procname	= "accept_dad",
4547 			.data		= &ipv6_devconf.accept_dad,
4548 			.maxlen		= sizeof(int),
4549 			.mode		= 0644,
4550 			.proc_handler	= proc_dointvec,
4551 		},
4552 		{
4553 			.procname       = "force_tllao",
4554 			.data           = &ipv6_devconf.force_tllao,
4555 			.maxlen         = sizeof(int),
4556 			.mode           = 0644,
4557 			.proc_handler   = proc_dointvec
4558 		},
4559 		{
4560 			/* sentinel */
4561 		}
4562 	},
4563 };
4564 
4565 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
4566 		struct inet6_dev *idev, struct ipv6_devconf *p)
4567 {
4568 	int i;
4569 	struct addrconf_sysctl_table *t;
4570 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
4571 
4572 	t = kmemdup(&addrconf_sysctl, sizeof(*t), GFP_KERNEL);
4573 	if (t == NULL)
4574 		goto out;
4575 
4576 	for (i = 0; t->addrconf_vars[i].data; i++) {
4577 		t->addrconf_vars[i].data += (char *)p - (char *)&ipv6_devconf;
4578 		t->addrconf_vars[i].extra1 = idev; /* embedded; no ref */
4579 		t->addrconf_vars[i].extra2 = net;
4580 	}
4581 
4582 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
4583 
4584 	t->sysctl_header = register_net_sysctl(net, path, t->addrconf_vars);
4585 	if (t->sysctl_header == NULL)
4586 		goto free;
4587 
4588 	p->sysctl = t;
4589 	return 0;
4590 
4591 free:
4592 	kfree(t);
4593 out:
4594 	return -ENOBUFS;
4595 }
4596 
4597 static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
4598 {
4599 	struct addrconf_sysctl_table *t;
4600 
4601 	if (p->sysctl == NULL)
4602 		return;
4603 
4604 	t = p->sysctl;
4605 	p->sysctl = NULL;
4606 	unregister_net_sysctl_table(t->sysctl_header);
4607 	kfree(t);
4608 }
4609 
4610 static void addrconf_sysctl_register(struct inet6_dev *idev)
4611 {
4612 	neigh_sysctl_register(idev->dev, idev->nd_parms, "ipv6",
4613 			      &ndisc_ifinfo_sysctl_change);
4614 	__addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
4615 					idev, &idev->cnf);
4616 }
4617 
4618 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
4619 {
4620 	__addrconf_sysctl_unregister(&idev->cnf);
4621 	neigh_sysctl_unregister(idev->nd_parms);
4622 }
4623 
4624 
4625 #endif
4626 
4627 static int __net_init addrconf_init_net(struct net *net)
4628 {
4629 	int err;
4630 	struct ipv6_devconf *all, *dflt;
4631 
4632 	err = -ENOMEM;
4633 	all = &ipv6_devconf;
4634 	dflt = &ipv6_devconf_dflt;
4635 
4636 	if (!net_eq(net, &init_net)) {
4637 		all = kmemdup(all, sizeof(ipv6_devconf), GFP_KERNEL);
4638 		if (all == NULL)
4639 			goto err_alloc_all;
4640 
4641 		dflt = kmemdup(dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
4642 		if (dflt == NULL)
4643 			goto err_alloc_dflt;
4644 	} else {
4645 		/* these will be inherited by all namespaces */
4646 		dflt->autoconf = ipv6_defaults.autoconf;
4647 		dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
4648 	}
4649 
4650 	net->ipv6.devconf_all = all;
4651 	net->ipv6.devconf_dflt = dflt;
4652 
4653 #ifdef CONFIG_SYSCTL
4654 	err = __addrconf_sysctl_register(net, "all", NULL, all);
4655 	if (err < 0)
4656 		goto err_reg_all;
4657 
4658 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
4659 	if (err < 0)
4660 		goto err_reg_dflt;
4661 #endif
4662 	return 0;
4663 
4664 #ifdef CONFIG_SYSCTL
4665 err_reg_dflt:
4666 	__addrconf_sysctl_unregister(all);
4667 err_reg_all:
4668 	kfree(dflt);
4669 #endif
4670 err_alloc_dflt:
4671 	kfree(all);
4672 err_alloc_all:
4673 	return err;
4674 }
4675 
4676 static void __net_exit addrconf_exit_net(struct net *net)
4677 {
4678 #ifdef CONFIG_SYSCTL
4679 	__addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
4680 	__addrconf_sysctl_unregister(net->ipv6.devconf_all);
4681 #endif
4682 	if (!net_eq(net, &init_net)) {
4683 		kfree(net->ipv6.devconf_dflt);
4684 		kfree(net->ipv6.devconf_all);
4685 	}
4686 }
4687 
4688 static struct pernet_operations addrconf_ops = {
4689 	.init = addrconf_init_net,
4690 	.exit = addrconf_exit_net,
4691 };
4692 
4693 /*
4694  *      Device notifier
4695  */
4696 
4697 int register_inet6addr_notifier(struct notifier_block *nb)
4698 {
4699 	return atomic_notifier_chain_register(&inet6addr_chain, nb);
4700 }
4701 EXPORT_SYMBOL(register_inet6addr_notifier);
4702 
4703 int unregister_inet6addr_notifier(struct notifier_block *nb)
4704 {
4705 	return atomic_notifier_chain_unregister(&inet6addr_chain, nb);
4706 }
4707 EXPORT_SYMBOL(unregister_inet6addr_notifier);
4708 
4709 static struct rtnl_af_ops inet6_ops = {
4710 	.family		  = AF_INET6,
4711 	.fill_link_af	  = inet6_fill_link_af,
4712 	.get_link_af_size = inet6_get_link_af_size,
4713 };
4714 
4715 /*
4716  *	Init / cleanup code
4717  */
4718 
4719 int __init addrconf_init(void)
4720 {
4721 	int i, err;
4722 
4723 	err = ipv6_addr_label_init();
4724 	if (err < 0) {
4725 		pr_crit("%s: cannot initialize default policy table: %d\n",
4726 			__func__, err);
4727 		goto out;
4728 	}
4729 
4730 	err = register_pernet_subsys(&addrconf_ops);
4731 	if (err < 0)
4732 		goto out_addrlabel;
4733 
4734 	/* The addrconf netdev notifier requires that loopback_dev
4735 	 * has it's ipv6 private information allocated and setup
4736 	 * before it can bring up and give link-local addresses
4737 	 * to other devices which are up.
4738 	 *
4739 	 * Unfortunately, loopback_dev is not necessarily the first
4740 	 * entry in the global dev_base list of net devices.  In fact,
4741 	 * it is likely to be the very last entry on that list.
4742 	 * So this causes the notifier registry below to try and
4743 	 * give link-local addresses to all devices besides loopback_dev
4744 	 * first, then loopback_dev, which cases all the non-loopback_dev
4745 	 * devices to fail to get a link-local address.
4746 	 *
4747 	 * So, as a temporary fix, allocate the ipv6 structure for
4748 	 * loopback_dev first by hand.
4749 	 * Longer term, all of the dependencies ipv6 has upon the loopback
4750 	 * device and it being up should be removed.
4751 	 */
4752 	rtnl_lock();
4753 	if (!ipv6_add_dev(init_net.loopback_dev))
4754 		err = -ENOMEM;
4755 	rtnl_unlock();
4756 	if (err)
4757 		goto errlo;
4758 
4759 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
4760 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
4761 
4762 	register_netdevice_notifier(&ipv6_dev_notf);
4763 
4764 	addrconf_verify(0);
4765 
4766 	err = rtnl_af_register(&inet6_ops);
4767 	if (err < 0)
4768 		goto errout_af;
4769 
4770 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
4771 			      NULL);
4772 	if (err < 0)
4773 		goto errout;
4774 
4775 	/* Only the first call to __rtnl_register can fail */
4776 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, NULL);
4777 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, NULL);
4778 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
4779 			inet6_dump_ifaddr, NULL);
4780 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
4781 			inet6_dump_ifmcaddr, NULL);
4782 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
4783 			inet6_dump_ifacaddr, NULL);
4784 
4785 	ipv6_addr_label_rtnl_register();
4786 
4787 	return 0;
4788 errout:
4789 	rtnl_af_unregister(&inet6_ops);
4790 errout_af:
4791 	unregister_netdevice_notifier(&ipv6_dev_notf);
4792 errlo:
4793 	unregister_pernet_subsys(&addrconf_ops);
4794 out_addrlabel:
4795 	ipv6_addr_label_cleanup();
4796 out:
4797 	return err;
4798 }
4799 
4800 void addrconf_cleanup(void)
4801 {
4802 	struct net_device *dev;
4803 	int i;
4804 
4805 	unregister_netdevice_notifier(&ipv6_dev_notf);
4806 	unregister_pernet_subsys(&addrconf_ops);
4807 	ipv6_addr_label_cleanup();
4808 
4809 	rtnl_lock();
4810 
4811 	__rtnl_af_unregister(&inet6_ops);
4812 
4813 	/* clean dev list */
4814 	for_each_netdev(&init_net, dev) {
4815 		if (__in6_dev_get(dev) == NULL)
4816 			continue;
4817 		addrconf_ifdown(dev, 1);
4818 	}
4819 	addrconf_ifdown(init_net.loopback_dev, 2);
4820 
4821 	/*
4822 	 *	Check hash table.
4823 	 */
4824 	spin_lock_bh(&addrconf_hash_lock);
4825 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
4826 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
4827 	spin_unlock_bh(&addrconf_hash_lock);
4828 
4829 	del_timer(&addr_chk_timer);
4830 	rtnl_unlock();
4831 }
4832