xref: /openbmc/linux/net/ipv6/addrconf.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
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 #include <linux/errno.h>
42 #include <linux/types.h>
43 #include <linux/kernel.h>
44 #include <linux/socket.h>
45 #include <linux/sockios.h>
46 #include <linux/net.h>
47 #include <linux/in6.h>
48 #include <linux/netdevice.h>
49 #include <linux/if_addr.h>
50 #include <linux/if_arp.h>
51 #include <linux/if_arcnet.h>
52 #include <linux/if_infiniband.h>
53 #include <linux/route.h>
54 #include <linux/inetdevice.h>
55 #include <linux/init.h>
56 #include <linux/slab.h>
57 #ifdef CONFIG_SYSCTL
58 #include <linux/sysctl.h>
59 #endif
60 #include <linux/capability.h>
61 #include <linux/delay.h>
62 #include <linux/notifier.h>
63 #include <linux/string.h>
64 
65 #include <net/net_namespace.h>
66 #include <net/sock.h>
67 #include <net/snmp.h>
68 
69 #include <net/ipv6.h>
70 #include <net/protocol.h>
71 #include <net/ndisc.h>
72 #include <net/ip6_route.h>
73 #include <net/addrconf.h>
74 #include <net/tcp.h>
75 #include <net/ip.h>
76 #include <net/netlink.h>
77 #include <net/pkt_sched.h>
78 #include <linux/if_tunnel.h>
79 #include <linux/rtnetlink.h>
80 
81 #ifdef CONFIG_IPV6_PRIVACY
82 #include <linux/random.h>
83 #endif
84 
85 #include <linux/uaccess.h>
86 #include <asm/unaligned.h>
87 
88 #include <linux/proc_fs.h>
89 #include <linux/seq_file.h>
90 
91 /* Set to 3 to get tracing... */
92 #define ACONF_DEBUG 2
93 
94 #if ACONF_DEBUG >= 3
95 #define ADBG(x) printk x
96 #else
97 #define ADBG(x)
98 #endif
99 
100 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
101 
102 static inline u32 cstamp_delta(unsigned long cstamp)
103 {
104 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
105 }
106 
107 #define ADDRCONF_TIMER_FUZZ_MINUS	(HZ > 50 ? HZ/50 : 1)
108 #define ADDRCONF_TIMER_FUZZ		(HZ / 4)
109 #define ADDRCONF_TIMER_FUZZ_MAX		(HZ)
110 
111 #ifdef CONFIG_SYSCTL
112 static void addrconf_sysctl_register(struct inet6_dev *idev);
113 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
114 #else
115 static inline void addrconf_sysctl_register(struct inet6_dev *idev)
116 {
117 }
118 
119 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
120 {
121 }
122 #endif
123 
124 #ifdef CONFIG_IPV6_PRIVACY
125 static int __ipv6_regen_rndid(struct inet6_dev *idev);
126 static int __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
127 static void ipv6_regen_rndid(unsigned long data);
128 #endif
129 
130 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
131 static int ipv6_count_addresses(struct inet6_dev *idev);
132 
133 /*
134  *	Configured unicast address hash table
135  */
136 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
137 static DEFINE_SPINLOCK(addrconf_hash_lock);
138 
139 static void addrconf_verify(unsigned long);
140 
141 static DEFINE_TIMER(addr_chk_timer, addrconf_verify, 0, 0);
142 static DEFINE_SPINLOCK(addrconf_verify_lock);
143 
144 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
145 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
146 
147 static void addrconf_type_change(struct net_device *dev,
148 				 unsigned long event);
149 static int addrconf_ifdown(struct net_device *dev, int how);
150 
151 static void addrconf_dad_start(struct inet6_ifaddr *ifp, u32 flags);
152 static void addrconf_dad_timer(unsigned long data);
153 static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
154 static void addrconf_dad_run(struct inet6_dev *idev);
155 static void addrconf_rs_timer(unsigned long data);
156 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
157 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
158 
159 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
160 				struct prefix_info *pinfo);
161 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
162 			       struct net_device *dev);
163 
164 static ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
165 
166 static struct ipv6_devconf ipv6_devconf __read_mostly = {
167 	.forwarding		= 0,
168 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
169 	.mtu6			= IPV6_MIN_MTU,
170 	.accept_ra		= 1,
171 	.accept_redirects	= 1,
172 	.autoconf		= 1,
173 	.force_mld_version	= 0,
174 	.dad_transmits		= 1,
175 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
176 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
177 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
178 #ifdef CONFIG_IPV6_PRIVACY
179 	.use_tempaddr 		= 0,
180 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
181 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
182 	.regen_max_retry	= REGEN_MAX_RETRY,
183 	.max_desync_factor	= MAX_DESYNC_FACTOR,
184 #endif
185 	.max_addresses		= IPV6_MAX_ADDRESSES,
186 	.accept_ra_defrtr	= 1,
187 	.accept_ra_pinfo	= 1,
188 #ifdef CONFIG_IPV6_ROUTER_PREF
189 	.accept_ra_rtr_pref	= 1,
190 	.rtr_probe_interval	= 60 * HZ,
191 #ifdef CONFIG_IPV6_ROUTE_INFO
192 	.accept_ra_rt_info_max_plen = 0,
193 #endif
194 #endif
195 	.proxy_ndp		= 0,
196 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
197 	.disable_ipv6		= 0,
198 	.accept_dad		= 1,
199 };
200 
201 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
202 	.forwarding		= 0,
203 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
204 	.mtu6			= IPV6_MIN_MTU,
205 	.accept_ra		= 1,
206 	.accept_redirects	= 1,
207 	.autoconf		= 1,
208 	.dad_transmits		= 1,
209 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
210 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
211 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
212 #ifdef CONFIG_IPV6_PRIVACY
213 	.use_tempaddr		= 0,
214 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
215 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
216 	.regen_max_retry	= REGEN_MAX_RETRY,
217 	.max_desync_factor	= MAX_DESYNC_FACTOR,
218 #endif
219 	.max_addresses		= IPV6_MAX_ADDRESSES,
220 	.accept_ra_defrtr	= 1,
221 	.accept_ra_pinfo	= 1,
222 #ifdef CONFIG_IPV6_ROUTER_PREF
223 	.accept_ra_rtr_pref	= 1,
224 	.rtr_probe_interval	= 60 * HZ,
225 #ifdef CONFIG_IPV6_ROUTE_INFO
226 	.accept_ra_rt_info_max_plen = 0,
227 #endif
228 #endif
229 	.proxy_ndp		= 0,
230 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
231 	.disable_ipv6		= 0,
232 	.accept_dad		= 1,
233 };
234 
235 /* IPv6 Wildcard Address and Loopback Address defined by RFC2553 */
236 const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
237 const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
238 const struct in6_addr in6addr_linklocal_allnodes = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
239 const struct in6_addr in6addr_linklocal_allrouters = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
240 
241 /* Check if a valid qdisc is available */
242 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
243 {
244 	return !qdisc_tx_is_noop(dev);
245 }
246 
247 /* Check if a route is valid prefix route */
248 static inline int addrconf_is_prefix_route(const struct rt6_info *rt)
249 {
250 	return (rt->rt6i_flags & (RTF_GATEWAY | RTF_DEFAULT)) == 0;
251 }
252 
253 static void addrconf_del_timer(struct inet6_ifaddr *ifp)
254 {
255 	if (del_timer(&ifp->timer))
256 		__in6_ifa_put(ifp);
257 }
258 
259 enum addrconf_timer_t {
260 	AC_NONE,
261 	AC_DAD,
262 	AC_RS,
263 };
264 
265 static void addrconf_mod_timer(struct inet6_ifaddr *ifp,
266 			       enum addrconf_timer_t what,
267 			       unsigned long when)
268 {
269 	if (!del_timer(&ifp->timer))
270 		in6_ifa_hold(ifp);
271 
272 	switch (what) {
273 	case AC_DAD:
274 		ifp->timer.function = addrconf_dad_timer;
275 		break;
276 	case AC_RS:
277 		ifp->timer.function = addrconf_rs_timer;
278 		break;
279 	default:
280 		break;
281 	}
282 	ifp->timer.expires = jiffies + when;
283 	add_timer(&ifp->timer);
284 }
285 
286 static int snmp6_alloc_dev(struct inet6_dev *idev)
287 {
288 	if (snmp_mib_init((void __percpu **)idev->stats.ipv6,
289 			  sizeof(struct ipstats_mib),
290 			  __alignof__(struct ipstats_mib)) < 0)
291 		goto err_ip;
292 	if (snmp_mib_init((void __percpu **)idev->stats.icmpv6,
293 			  sizeof(struct icmpv6_mib),
294 			  __alignof__(struct icmpv6_mib)) < 0)
295 		goto err_icmp;
296 	if (snmp_mib_init((void __percpu **)idev->stats.icmpv6msg,
297 			  sizeof(struct icmpv6msg_mib),
298 			  __alignof__(struct icmpv6msg_mib)) < 0)
299 		goto err_icmpmsg;
300 
301 	return 0;
302 
303 err_icmpmsg:
304 	snmp_mib_free((void __percpu **)idev->stats.icmpv6);
305 err_icmp:
306 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
307 err_ip:
308 	return -ENOMEM;
309 }
310 
311 static void snmp6_free_dev(struct inet6_dev *idev)
312 {
313 	snmp_mib_free((void __percpu **)idev->stats.icmpv6msg);
314 	snmp_mib_free((void __percpu **)idev->stats.icmpv6);
315 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
316 }
317 
318 /* Nobody refers to this device, we may destroy it. */
319 
320 static void in6_dev_finish_destroy_rcu(struct rcu_head *head)
321 {
322 	struct inet6_dev *idev = container_of(head, struct inet6_dev, rcu);
323 	kfree(idev);
324 }
325 
326 void in6_dev_finish_destroy(struct inet6_dev *idev)
327 {
328 	struct net_device *dev = idev->dev;
329 
330 	WARN_ON(!list_empty(&idev->addr_list));
331 	WARN_ON(idev->mc_list != NULL);
332 
333 #ifdef NET_REFCNT_DEBUG
334 	printk(KERN_DEBUG "in6_dev_finish_destroy: %s\n", dev ? dev->name : "NIL");
335 #endif
336 	dev_put(dev);
337 	if (!idev->dead) {
338 		pr_warning("Freeing alive inet6 device %p\n", idev);
339 		return;
340 	}
341 	snmp6_free_dev(idev);
342 	call_rcu(&idev->rcu, in6_dev_finish_destroy_rcu);
343 }
344 
345 EXPORT_SYMBOL(in6_dev_finish_destroy);
346 
347 static struct inet6_dev * ipv6_add_dev(struct net_device *dev)
348 {
349 	struct inet6_dev *ndev;
350 
351 	ASSERT_RTNL();
352 
353 	if (dev->mtu < IPV6_MIN_MTU)
354 		return NULL;
355 
356 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
357 
358 	if (ndev == NULL)
359 		return NULL;
360 
361 	rwlock_init(&ndev->lock);
362 	ndev->dev = dev;
363 	INIT_LIST_HEAD(&ndev->addr_list);
364 
365 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
366 	ndev->cnf.mtu6 = dev->mtu;
367 	ndev->cnf.sysctl = NULL;
368 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
369 	if (ndev->nd_parms == NULL) {
370 		kfree(ndev);
371 		return NULL;
372 	}
373 	if (ndev->cnf.forwarding)
374 		dev_disable_lro(dev);
375 	/* We refer to the device */
376 	dev_hold(dev);
377 
378 	if (snmp6_alloc_dev(ndev) < 0) {
379 		ADBG((KERN_WARNING
380 			"%s(): cannot allocate memory for statistics; dev=%s.\n",
381 			__func__, dev->name));
382 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
383 		ndev->dead = 1;
384 		in6_dev_finish_destroy(ndev);
385 		return NULL;
386 	}
387 
388 	if (snmp6_register_dev(ndev) < 0) {
389 		ADBG((KERN_WARNING
390 			"%s(): cannot create /proc/net/dev_snmp6/%s\n",
391 			__func__, dev->name));
392 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
393 		ndev->dead = 1;
394 		in6_dev_finish_destroy(ndev);
395 		return NULL;
396 	}
397 
398 	/* One reference from device.  We must do this before
399 	 * we invoke __ipv6_regen_rndid().
400 	 */
401 	in6_dev_hold(ndev);
402 
403 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
404 		ndev->cnf.accept_dad = -1;
405 
406 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
407 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
408 		printk(KERN_INFO
409 		       "%s: Disabled Multicast RS\n",
410 		       dev->name);
411 		ndev->cnf.rtr_solicits = 0;
412 	}
413 #endif
414 
415 #ifdef CONFIG_IPV6_PRIVACY
416 	INIT_LIST_HEAD(&ndev->tempaddr_list);
417 	setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
418 	if ((dev->flags&IFF_LOOPBACK) ||
419 	    dev->type == ARPHRD_TUNNEL ||
420 	    dev->type == ARPHRD_TUNNEL6 ||
421 	    dev->type == ARPHRD_SIT ||
422 	    dev->type == ARPHRD_NONE) {
423 		printk(KERN_INFO
424 		       "%s: Disabled Privacy Extensions\n",
425 		       dev->name);
426 		ndev->cnf.use_tempaddr = -1;
427 	} else {
428 		in6_dev_hold(ndev);
429 		ipv6_regen_rndid((unsigned long) ndev);
430 	}
431 #endif
432 
433 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
434 		ndev->if_flags |= IF_READY;
435 
436 	ipv6_mc_init_dev(ndev);
437 	ndev->tstamp = jiffies;
438 	addrconf_sysctl_register(ndev);
439 	/* protected by rtnl_lock */
440 	rcu_assign_pointer(dev->ip6_ptr, ndev);
441 
442 	/* Join all-node multicast group */
443 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
444 
445 	return ndev;
446 }
447 
448 static struct inet6_dev * ipv6_find_idev(struct net_device *dev)
449 {
450 	struct inet6_dev *idev;
451 
452 	ASSERT_RTNL();
453 
454 	idev = __in6_dev_get(dev);
455 	if (!idev) {
456 		idev = ipv6_add_dev(dev);
457 		if (!idev)
458 			return NULL;
459 	}
460 
461 	if (dev->flags&IFF_UP)
462 		ipv6_mc_up(idev);
463 	return idev;
464 }
465 
466 #ifdef CONFIG_SYSCTL
467 static void dev_forward_change(struct inet6_dev *idev)
468 {
469 	struct net_device *dev;
470 	struct inet6_ifaddr *ifa;
471 
472 	if (!idev)
473 		return;
474 	dev = idev->dev;
475 	if (idev->cnf.forwarding)
476 		dev_disable_lro(dev);
477 	if (dev && (dev->flags & IFF_MULTICAST)) {
478 		if (idev->cnf.forwarding)
479 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
480 		else
481 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
482 	}
483 
484 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
485 		if (ifa->flags&IFA_F_TENTATIVE)
486 			continue;
487 		if (idev->cnf.forwarding)
488 			addrconf_join_anycast(ifa);
489 		else
490 			addrconf_leave_anycast(ifa);
491 	}
492 }
493 
494 
495 static void addrconf_forward_change(struct net *net, __s32 newf)
496 {
497 	struct net_device *dev;
498 	struct inet6_dev *idev;
499 
500 	rcu_read_lock();
501 	for_each_netdev_rcu(net, dev) {
502 		idev = __in6_dev_get(dev);
503 		if (idev) {
504 			int changed = (!idev->cnf.forwarding) ^ (!newf);
505 			idev->cnf.forwarding = newf;
506 			if (changed)
507 				dev_forward_change(idev);
508 		}
509 	}
510 	rcu_read_unlock();
511 }
512 
513 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int old)
514 {
515 	struct net *net;
516 
517 	net = (struct net *)table->extra2;
518 	if (p == &net->ipv6.devconf_dflt->forwarding)
519 		return 0;
520 
521 	if (!rtnl_trylock()) {
522 		/* Restore the original values before restarting */
523 		*p = old;
524 		return restart_syscall();
525 	}
526 
527 	if (p == &net->ipv6.devconf_all->forwarding) {
528 		__s32 newf = net->ipv6.devconf_all->forwarding;
529 		net->ipv6.devconf_dflt->forwarding = newf;
530 		addrconf_forward_change(net, newf);
531 	} else if ((!*p) ^ (!old))
532 		dev_forward_change((struct inet6_dev *)table->extra1);
533 	rtnl_unlock();
534 
535 	if (*p)
536 		rt6_purge_dflt_routers(net);
537 	return 1;
538 }
539 #endif
540 
541 static void inet6_ifa_finish_destroy_rcu(struct rcu_head *head)
542 {
543 	struct inet6_ifaddr *ifp = container_of(head, struct inet6_ifaddr, rcu);
544 	kfree(ifp);
545 }
546 
547 /* Nobody refers to this ifaddr, destroy it */
548 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
549 {
550 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
551 
552 #ifdef NET_REFCNT_DEBUG
553 	printk(KERN_DEBUG "inet6_ifa_finish_destroy\n");
554 #endif
555 
556 	in6_dev_put(ifp->idev);
557 
558 	if (del_timer(&ifp->timer))
559 		pr_notice("Timer is still running, when freeing ifa=%p\n", ifp);
560 
561 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
562 		pr_warning("Freeing alive inet6 address %p\n", ifp);
563 		return;
564 	}
565 	dst_release(&ifp->rt->dst);
566 
567 	call_rcu(&ifp->rcu, inet6_ifa_finish_destroy_rcu);
568 }
569 
570 static void
571 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
572 {
573 	struct list_head *p;
574 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
575 
576 	/*
577 	 * Each device address list is sorted in order of scope -
578 	 * global before linklocal.
579 	 */
580 	list_for_each(p, &idev->addr_list) {
581 		struct inet6_ifaddr *ifa
582 			= list_entry(p, struct inet6_ifaddr, if_list);
583 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
584 			break;
585 	}
586 
587 	list_add_tail(&ifp->if_list, p);
588 }
589 
590 static u32 ipv6_addr_hash(const struct in6_addr *addr)
591 {
592 	/*
593 	 * We perform the hash function over the last 64 bits of the address
594 	 * This will include the IEEE address token on links that support it.
595 	 */
596 	return jhash_2words((__force u32)addr->s6_addr32[2],
597 			    (__force u32)addr->s6_addr32[3], 0)
598 		& (IN6_ADDR_HSIZE - 1);
599 }
600 
601 /* On success it returns ifp with increased reference count */
602 
603 static struct inet6_ifaddr *
604 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen,
605 	      int scope, u32 flags)
606 {
607 	struct inet6_ifaddr *ifa = NULL;
608 	struct rt6_info *rt;
609 	unsigned int hash;
610 	int err = 0;
611 	int addr_type = ipv6_addr_type(addr);
612 
613 	if (addr_type == IPV6_ADDR_ANY ||
614 	    addr_type & IPV6_ADDR_MULTICAST ||
615 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
616 	     addr_type & IPV6_ADDR_LOOPBACK))
617 		return ERR_PTR(-EADDRNOTAVAIL);
618 
619 	rcu_read_lock_bh();
620 	if (idev->dead) {
621 		err = -ENODEV;			/*XXX*/
622 		goto out2;
623 	}
624 
625 	if (idev->cnf.disable_ipv6) {
626 		err = -EACCES;
627 		goto out2;
628 	}
629 
630 	spin_lock(&addrconf_hash_lock);
631 
632 	/* Ignore adding duplicate addresses on an interface */
633 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
634 		ADBG(("ipv6_add_addr: already assigned\n"));
635 		err = -EEXIST;
636 		goto out;
637 	}
638 
639 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
640 
641 	if (ifa == NULL) {
642 		ADBG(("ipv6_add_addr: malloc failed\n"));
643 		err = -ENOBUFS;
644 		goto out;
645 	}
646 
647 	rt = addrconf_dst_alloc(idev, addr, 0);
648 	if (IS_ERR(rt)) {
649 		err = PTR_ERR(rt);
650 		goto out;
651 	}
652 
653 	ipv6_addr_copy(&ifa->addr, addr);
654 
655 	spin_lock_init(&ifa->lock);
656 	spin_lock_init(&ifa->state_lock);
657 	init_timer(&ifa->timer);
658 	INIT_HLIST_NODE(&ifa->addr_lst);
659 	ifa->timer.data = (unsigned long) ifa;
660 	ifa->scope = scope;
661 	ifa->prefix_len = pfxlen;
662 	ifa->flags = flags | IFA_F_TENTATIVE;
663 	ifa->cstamp = ifa->tstamp = jiffies;
664 
665 	ifa->rt = rt;
666 
667 	/*
668 	 * part one of RFC 4429, section 3.3
669 	 * We should not configure an address as
670 	 * optimistic if we do not yet know the link
671 	 * layer address of our nexhop router
672 	 */
673 
674 	if (rt->rt6i_nexthop == NULL)
675 		ifa->flags &= ~IFA_F_OPTIMISTIC;
676 
677 	ifa->idev = idev;
678 	in6_dev_hold(idev);
679 	/* For caller */
680 	in6_ifa_hold(ifa);
681 
682 	/* Add to big hash table */
683 	hash = ipv6_addr_hash(addr);
684 
685 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
686 	spin_unlock(&addrconf_hash_lock);
687 
688 	write_lock(&idev->lock);
689 	/* Add to inet6_dev unicast addr list. */
690 	ipv6_link_dev_addr(idev, ifa);
691 
692 #ifdef CONFIG_IPV6_PRIVACY
693 	if (ifa->flags&IFA_F_TEMPORARY) {
694 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
695 		in6_ifa_hold(ifa);
696 	}
697 #endif
698 
699 	in6_ifa_hold(ifa);
700 	write_unlock(&idev->lock);
701 out2:
702 	rcu_read_unlock_bh();
703 
704 	if (likely(err == 0))
705 		atomic_notifier_call_chain(&inet6addr_chain, NETDEV_UP, ifa);
706 	else {
707 		kfree(ifa);
708 		ifa = ERR_PTR(err);
709 	}
710 
711 	return ifa;
712 out:
713 	spin_unlock(&addrconf_hash_lock);
714 	goto out2;
715 }
716 
717 /* This function wants to get referenced ifp and releases it before return */
718 
719 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
720 {
721 	struct inet6_ifaddr *ifa, *ifn;
722 	struct inet6_dev *idev = ifp->idev;
723 	int state;
724 	int hash;
725 	int deleted = 0, onlink = 0;
726 	unsigned long expires = jiffies;
727 
728 	hash = ipv6_addr_hash(&ifp->addr);
729 
730 	spin_lock_bh(&ifp->state_lock);
731 	state = ifp->state;
732 	ifp->state = INET6_IFADDR_STATE_DEAD;
733 	spin_unlock_bh(&ifp->state_lock);
734 
735 	if (state == INET6_IFADDR_STATE_DEAD)
736 		goto out;
737 
738 	spin_lock_bh(&addrconf_hash_lock);
739 	hlist_del_init_rcu(&ifp->addr_lst);
740 	spin_unlock_bh(&addrconf_hash_lock);
741 
742 	write_lock_bh(&idev->lock);
743 #ifdef CONFIG_IPV6_PRIVACY
744 	if (ifp->flags&IFA_F_TEMPORARY) {
745 		list_del(&ifp->tmp_list);
746 		if (ifp->ifpub) {
747 			in6_ifa_put(ifp->ifpub);
748 			ifp->ifpub = NULL;
749 		}
750 		__in6_ifa_put(ifp);
751 	}
752 #endif
753 
754 	list_for_each_entry_safe(ifa, ifn, &idev->addr_list, if_list) {
755 		if (ifa == ifp) {
756 			list_del_init(&ifp->if_list);
757 			__in6_ifa_put(ifp);
758 
759 			if (!(ifp->flags & IFA_F_PERMANENT) || onlink > 0)
760 				break;
761 			deleted = 1;
762 			continue;
763 		} else if (ifp->flags & IFA_F_PERMANENT) {
764 			if (ipv6_prefix_equal(&ifa->addr, &ifp->addr,
765 					      ifp->prefix_len)) {
766 				if (ifa->flags & IFA_F_PERMANENT) {
767 					onlink = 1;
768 					if (deleted)
769 						break;
770 				} else {
771 					unsigned long lifetime;
772 
773 					if (!onlink)
774 						onlink = -1;
775 
776 					spin_lock(&ifa->lock);
777 
778 					lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
779 					/*
780 					 * Note: Because this address is
781 					 * not permanent, lifetime <
782 					 * LONG_MAX / HZ here.
783 					 */
784 					if (time_before(expires,
785 							ifa->tstamp + lifetime * HZ))
786 						expires = ifa->tstamp + lifetime * HZ;
787 					spin_unlock(&ifa->lock);
788 				}
789 			}
790 		}
791 	}
792 	write_unlock_bh(&idev->lock);
793 
794 	addrconf_del_timer(ifp);
795 
796 	ipv6_ifa_notify(RTM_DELADDR, ifp);
797 
798 	atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifp);
799 
800 	/*
801 	 * Purge or update corresponding prefix
802 	 *
803 	 * 1) we don't purge prefix here if address was not permanent.
804 	 *    prefix is managed by its own lifetime.
805 	 * 2) if there're no addresses, delete prefix.
806 	 * 3) if there're still other permanent address(es),
807 	 *    corresponding prefix is still permanent.
808 	 * 4) otherwise, update prefix lifetime to the
809 	 *    longest valid lifetime among the corresponding
810 	 *    addresses on the device.
811 	 *    Note: subsequent RA will update lifetime.
812 	 *
813 	 * --yoshfuji
814 	 */
815 	if ((ifp->flags & IFA_F_PERMANENT) && onlink < 1) {
816 		struct in6_addr prefix;
817 		struct rt6_info *rt;
818 		struct net *net = dev_net(ifp->idev->dev);
819 		ipv6_addr_prefix(&prefix, &ifp->addr, ifp->prefix_len);
820 		rt = rt6_lookup(net, &prefix, NULL, ifp->idev->dev->ifindex, 1);
821 
822 		if (rt && addrconf_is_prefix_route(rt)) {
823 			if (onlink == 0) {
824 				ip6_del_rt(rt);
825 				rt = NULL;
826 			} else if (!(rt->rt6i_flags & RTF_EXPIRES)) {
827 				rt->rt6i_expires = expires;
828 				rt->rt6i_flags |= RTF_EXPIRES;
829 			}
830 		}
831 		dst_release(&rt->dst);
832 	}
833 
834 out:
835 	in6_ifa_put(ifp);
836 }
837 
838 #ifdef CONFIG_IPV6_PRIVACY
839 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
840 {
841 	struct inet6_dev *idev = ifp->idev;
842 	struct in6_addr addr, *tmpaddr;
843 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_cstamp, tmp_tstamp, age;
844 	unsigned long regen_advance;
845 	int tmp_plen;
846 	int ret = 0;
847 	int max_addresses;
848 	u32 addr_flags;
849 
850 	write_lock(&idev->lock);
851 	if (ift) {
852 		spin_lock_bh(&ift->lock);
853 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
854 		spin_unlock_bh(&ift->lock);
855 		tmpaddr = &addr;
856 	} else {
857 		tmpaddr = NULL;
858 	}
859 retry:
860 	in6_dev_hold(idev);
861 	if (idev->cnf.use_tempaddr <= 0) {
862 		write_unlock(&idev->lock);
863 		printk(KERN_INFO
864 			"ipv6_create_tempaddr(): use_tempaddr is disabled.\n");
865 		in6_dev_put(idev);
866 		ret = -1;
867 		goto out;
868 	}
869 	spin_lock_bh(&ifp->lock);
870 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
871 		idev->cnf.use_tempaddr = -1;	/*XXX*/
872 		spin_unlock_bh(&ifp->lock);
873 		write_unlock(&idev->lock);
874 		printk(KERN_WARNING
875 			"ipv6_create_tempaddr(): regeneration time exceeded. disabled temporary address support.\n");
876 		in6_dev_put(idev);
877 		ret = -1;
878 		goto out;
879 	}
880 	in6_ifa_hold(ifp);
881 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
882 	if (__ipv6_try_regen_rndid(idev, tmpaddr) < 0) {
883 		spin_unlock_bh(&ifp->lock);
884 		write_unlock(&idev->lock);
885 		printk(KERN_WARNING
886 			"ipv6_create_tempaddr(): regeneration of randomized interface id failed.\n");
887 		in6_ifa_put(ifp);
888 		in6_dev_put(idev);
889 		ret = -1;
890 		goto out;
891 	}
892 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
893 	age = (jiffies - ifp->tstamp) / HZ;
894 	tmp_valid_lft = min_t(__u32,
895 			      ifp->valid_lft,
896 			      idev->cnf.temp_valid_lft + age);
897 	tmp_prefered_lft = min_t(__u32,
898 				 ifp->prefered_lft,
899 				 idev->cnf.temp_prefered_lft + age -
900 				 idev->cnf.max_desync_factor);
901 	tmp_plen = ifp->prefix_len;
902 	max_addresses = idev->cnf.max_addresses;
903 	tmp_cstamp = ifp->cstamp;
904 	tmp_tstamp = ifp->tstamp;
905 	spin_unlock_bh(&ifp->lock);
906 
907 	regen_advance = idev->cnf.regen_max_retry *
908 	                idev->cnf.dad_transmits *
909 	                idev->nd_parms->retrans_time / HZ;
910 	write_unlock(&idev->lock);
911 
912 	/* A temporary address is created only if this calculated Preferred
913 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
914 	 * an implementation must not create a temporary address with a zero
915 	 * Preferred Lifetime.
916 	 */
917 	if (tmp_prefered_lft <= regen_advance) {
918 		in6_ifa_put(ifp);
919 		in6_dev_put(idev);
920 		ret = -1;
921 		goto out;
922 	}
923 
924 	addr_flags = IFA_F_TEMPORARY;
925 	/* set in addrconf_prefix_rcv() */
926 	if (ifp->flags & IFA_F_OPTIMISTIC)
927 		addr_flags |= IFA_F_OPTIMISTIC;
928 
929 	ift = !max_addresses ||
930 	      ipv6_count_addresses(idev) < max_addresses ?
931 		ipv6_add_addr(idev, &addr, tmp_plen,
932 			      ipv6_addr_type(&addr)&IPV6_ADDR_SCOPE_MASK,
933 			      addr_flags) : NULL;
934 	if (!ift || IS_ERR(ift)) {
935 		in6_ifa_put(ifp);
936 		in6_dev_put(idev);
937 		printk(KERN_INFO
938 			"ipv6_create_tempaddr(): retry temporary address regeneration.\n");
939 		tmpaddr = &addr;
940 		write_lock(&idev->lock);
941 		goto retry;
942 	}
943 
944 	spin_lock_bh(&ift->lock);
945 	ift->ifpub = ifp;
946 	ift->valid_lft = tmp_valid_lft;
947 	ift->prefered_lft = tmp_prefered_lft;
948 	ift->cstamp = tmp_cstamp;
949 	ift->tstamp = tmp_tstamp;
950 	spin_unlock_bh(&ift->lock);
951 
952 	addrconf_dad_start(ift, 0);
953 	in6_ifa_put(ift);
954 	in6_dev_put(idev);
955 out:
956 	return ret;
957 }
958 #endif
959 
960 /*
961  *	Choose an appropriate source address (RFC3484)
962  */
963 enum {
964 	IPV6_SADDR_RULE_INIT = 0,
965 	IPV6_SADDR_RULE_LOCAL,
966 	IPV6_SADDR_RULE_SCOPE,
967 	IPV6_SADDR_RULE_PREFERRED,
968 #ifdef CONFIG_IPV6_MIP6
969 	IPV6_SADDR_RULE_HOA,
970 #endif
971 	IPV6_SADDR_RULE_OIF,
972 	IPV6_SADDR_RULE_LABEL,
973 #ifdef CONFIG_IPV6_PRIVACY
974 	IPV6_SADDR_RULE_PRIVACY,
975 #endif
976 	IPV6_SADDR_RULE_ORCHID,
977 	IPV6_SADDR_RULE_PREFIX,
978 	IPV6_SADDR_RULE_MAX
979 };
980 
981 struct ipv6_saddr_score {
982 	int			rule;
983 	int			addr_type;
984 	struct inet6_ifaddr	*ifa;
985 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
986 	int			scopedist;
987 	int			matchlen;
988 };
989 
990 struct ipv6_saddr_dst {
991 	const struct in6_addr *addr;
992 	int ifindex;
993 	int scope;
994 	int label;
995 	unsigned int prefs;
996 };
997 
998 static inline int ipv6_saddr_preferred(int type)
999 {
1000 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1001 		return 1;
1002 	return 0;
1003 }
1004 
1005 static int ipv6_get_saddr_eval(struct net *net,
1006 			       struct ipv6_saddr_score *score,
1007 			       struct ipv6_saddr_dst *dst,
1008 			       int i)
1009 {
1010 	int ret;
1011 
1012 	if (i <= score->rule) {
1013 		switch (i) {
1014 		case IPV6_SADDR_RULE_SCOPE:
1015 			ret = score->scopedist;
1016 			break;
1017 		case IPV6_SADDR_RULE_PREFIX:
1018 			ret = score->matchlen;
1019 			break;
1020 		default:
1021 			ret = !!test_bit(i, score->scorebits);
1022 		}
1023 		goto out;
1024 	}
1025 
1026 	switch (i) {
1027 	case IPV6_SADDR_RULE_INIT:
1028 		/* Rule 0: remember if hiscore is not ready yet */
1029 		ret = !!score->ifa;
1030 		break;
1031 	case IPV6_SADDR_RULE_LOCAL:
1032 		/* Rule 1: Prefer same address */
1033 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1034 		break;
1035 	case IPV6_SADDR_RULE_SCOPE:
1036 		/* Rule 2: Prefer appropriate scope
1037 		 *
1038 		 *      ret
1039 		 *       ^
1040 		 *    -1 |  d 15
1041 		 *    ---+--+-+---> scope
1042 		 *       |
1043 		 *       |             d is scope of the destination.
1044 		 *  B-d  |  \
1045 		 *       |   \      <- smaller scope is better if
1046 		 *  B-15 |    \        if scope is enough for destinaion.
1047 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1048 		 * d-C-1 | /
1049 		 *       |/         <- greater is better
1050 		 *   -C  /             if scope is not enough for destination.
1051 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1052 		 *
1053 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1054 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1055 		 * Assume B = 0 and we get C > 29.
1056 		 */
1057 		ret = __ipv6_addr_src_scope(score->addr_type);
1058 		if (ret >= dst->scope)
1059 			ret = -ret;
1060 		else
1061 			ret -= 128;	/* 30 is enough */
1062 		score->scopedist = ret;
1063 		break;
1064 	case IPV6_SADDR_RULE_PREFERRED:
1065 		/* Rule 3: Avoid deprecated and optimistic addresses */
1066 		ret = ipv6_saddr_preferred(score->addr_type) ||
1067 		      !(score->ifa->flags & (IFA_F_DEPRECATED|IFA_F_OPTIMISTIC));
1068 		break;
1069 #ifdef CONFIG_IPV6_MIP6
1070 	case IPV6_SADDR_RULE_HOA:
1071 	    {
1072 		/* Rule 4: Prefer home address */
1073 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1074 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1075 		break;
1076 	    }
1077 #endif
1078 	case IPV6_SADDR_RULE_OIF:
1079 		/* Rule 5: Prefer outgoing interface */
1080 		ret = (!dst->ifindex ||
1081 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1082 		break;
1083 	case IPV6_SADDR_RULE_LABEL:
1084 		/* Rule 6: Prefer matching label */
1085 		ret = ipv6_addr_label(net,
1086 				      &score->ifa->addr, score->addr_type,
1087 				      score->ifa->idev->dev->ifindex) == dst->label;
1088 		break;
1089 #ifdef CONFIG_IPV6_PRIVACY
1090 	case IPV6_SADDR_RULE_PRIVACY:
1091 	    {
1092 		/* Rule 7: Prefer public address
1093 		 * Note: prefer temprary address if use_tempaddr >= 2
1094 		 */
1095 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1096 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1097 				score->ifa->idev->cnf.use_tempaddr >= 2;
1098 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1099 		break;
1100 	    }
1101 #endif
1102 	case IPV6_SADDR_RULE_ORCHID:
1103 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1104 		 *	    non-ORCHID vs non-ORCHID
1105 		 */
1106 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1107 			ipv6_addr_orchid(dst->addr));
1108 		break;
1109 	case IPV6_SADDR_RULE_PREFIX:
1110 		/* Rule 8: Use longest matching prefix */
1111 		score->matchlen = ret = ipv6_addr_diff(&score->ifa->addr,
1112 						       dst->addr);
1113 		break;
1114 	default:
1115 		ret = 0;
1116 	}
1117 
1118 	if (ret)
1119 		__set_bit(i, score->scorebits);
1120 	score->rule = i;
1121 out:
1122 	return ret;
1123 }
1124 
1125 int ipv6_dev_get_saddr(struct net *net, struct net_device *dst_dev,
1126 		       const struct in6_addr *daddr, unsigned int prefs,
1127 		       struct in6_addr *saddr)
1128 {
1129 	struct ipv6_saddr_score scores[2],
1130 				*score = &scores[0], *hiscore = &scores[1];
1131 	struct ipv6_saddr_dst dst;
1132 	struct net_device *dev;
1133 	int dst_type;
1134 
1135 	dst_type = __ipv6_addr_type(daddr);
1136 	dst.addr = daddr;
1137 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1138 	dst.scope = __ipv6_addr_src_scope(dst_type);
1139 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1140 	dst.prefs = prefs;
1141 
1142 	hiscore->rule = -1;
1143 	hiscore->ifa = NULL;
1144 
1145 	rcu_read_lock();
1146 
1147 	for_each_netdev_rcu(net, dev) {
1148 		struct inet6_dev *idev;
1149 
1150 		/* Candidate Source Address (section 4)
1151 		 *  - multicast and link-local destination address,
1152 		 *    the set of candidate source address MUST only
1153 		 *    include addresses assigned to interfaces
1154 		 *    belonging to the same link as the outgoing
1155 		 *    interface.
1156 		 * (- For site-local destination addresses, the
1157 		 *    set of candidate source addresses MUST only
1158 		 *    include addresses assigned to interfaces
1159 		 *    belonging to the same site as the outgoing
1160 		 *    interface.)
1161 		 */
1162 		if (((dst_type & IPV6_ADDR_MULTICAST) ||
1163 		     dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) &&
1164 		    dst.ifindex && dev->ifindex != dst.ifindex)
1165 			continue;
1166 
1167 		idev = __in6_dev_get(dev);
1168 		if (!idev)
1169 			continue;
1170 
1171 		read_lock_bh(&idev->lock);
1172 		list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1173 			int i;
1174 
1175 			/*
1176 			 * - Tentative Address (RFC2462 section 5.4)
1177 			 *  - A tentative address is not considered
1178 			 *    "assigned to an interface" in the traditional
1179 			 *    sense, unless it is also flagged as optimistic.
1180 			 * - Candidate Source Address (section 4)
1181 			 *  - In any case, anycast addresses, multicast
1182 			 *    addresses, and the unspecified address MUST
1183 			 *    NOT be included in a candidate set.
1184 			 */
1185 			if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1186 			    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1187 				continue;
1188 
1189 			score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1190 
1191 			if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1192 				     score->addr_type & IPV6_ADDR_MULTICAST)) {
1193 				LIMIT_NETDEBUG(KERN_DEBUG
1194 					       "ADDRCONF: unspecified / multicast address "
1195 					       "assigned as unicast address on %s",
1196 					       dev->name);
1197 				continue;
1198 			}
1199 
1200 			score->rule = -1;
1201 			bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1202 
1203 			for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1204 				int minihiscore, miniscore;
1205 
1206 				minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
1207 				miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
1208 
1209 				if (minihiscore > miniscore) {
1210 					if (i == IPV6_SADDR_RULE_SCOPE &&
1211 					    score->scopedist > 0) {
1212 						/*
1213 						 * special case:
1214 						 * each remaining entry
1215 						 * has too small (not enough)
1216 						 * scope, because ifa entries
1217 						 * are sorted by their scope
1218 						 * values.
1219 						 */
1220 						goto try_nextdev;
1221 					}
1222 					break;
1223 				} else if (minihiscore < miniscore) {
1224 					if (hiscore->ifa)
1225 						in6_ifa_put(hiscore->ifa);
1226 
1227 					in6_ifa_hold(score->ifa);
1228 
1229 					swap(hiscore, score);
1230 
1231 					/* restore our iterator */
1232 					score->ifa = hiscore->ifa;
1233 
1234 					break;
1235 				}
1236 			}
1237 		}
1238 try_nextdev:
1239 		read_unlock_bh(&idev->lock);
1240 	}
1241 	rcu_read_unlock();
1242 
1243 	if (!hiscore->ifa)
1244 		return -EADDRNOTAVAIL;
1245 
1246 	ipv6_addr_copy(saddr, &hiscore->ifa->addr);
1247 	in6_ifa_put(hiscore->ifa);
1248 	return 0;
1249 }
1250 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1251 
1252 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1253 		    unsigned char banned_flags)
1254 {
1255 	struct inet6_dev *idev;
1256 	int err = -EADDRNOTAVAIL;
1257 
1258 	rcu_read_lock();
1259 	idev = __in6_dev_get(dev);
1260 	if (idev) {
1261 		struct inet6_ifaddr *ifp;
1262 
1263 		read_lock_bh(&idev->lock);
1264 		list_for_each_entry(ifp, &idev->addr_list, if_list) {
1265 			if (ifp->scope == IFA_LINK &&
1266 			    !(ifp->flags & banned_flags)) {
1267 				ipv6_addr_copy(addr, &ifp->addr);
1268 				err = 0;
1269 				break;
1270 			}
1271 		}
1272 		read_unlock_bh(&idev->lock);
1273 	}
1274 	rcu_read_unlock();
1275 	return err;
1276 }
1277 
1278 static int ipv6_count_addresses(struct inet6_dev *idev)
1279 {
1280 	int cnt = 0;
1281 	struct inet6_ifaddr *ifp;
1282 
1283 	read_lock_bh(&idev->lock);
1284 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1285 		cnt++;
1286 	read_unlock_bh(&idev->lock);
1287 	return cnt;
1288 }
1289 
1290 int ipv6_chk_addr(struct net *net, struct in6_addr *addr,
1291 		  struct net_device *dev, int strict)
1292 {
1293 	struct inet6_ifaddr *ifp;
1294 	struct hlist_node *node;
1295 	unsigned int hash = ipv6_addr_hash(addr);
1296 
1297 	rcu_read_lock_bh();
1298 	hlist_for_each_entry_rcu(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1299 		if (!net_eq(dev_net(ifp->idev->dev), net))
1300 			continue;
1301 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1302 		    !(ifp->flags&IFA_F_TENTATIVE) &&
1303 		    (dev == NULL || ifp->idev->dev == dev ||
1304 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1305 			rcu_read_unlock_bh();
1306 			return 1;
1307 		}
1308 	}
1309 
1310 	rcu_read_unlock_bh();
1311 	return 0;
1312 }
1313 EXPORT_SYMBOL(ipv6_chk_addr);
1314 
1315 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1316 			       struct net_device *dev)
1317 {
1318 	unsigned int hash = ipv6_addr_hash(addr);
1319 	struct inet6_ifaddr *ifp;
1320 	struct hlist_node *node;
1321 
1322 	hlist_for_each_entry(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1323 		if (!net_eq(dev_net(ifp->idev->dev), net))
1324 			continue;
1325 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1326 			if (dev == NULL || ifp->idev->dev == dev)
1327 				return true;
1328 		}
1329 	}
1330 	return false;
1331 }
1332 
1333 int ipv6_chk_prefix(struct in6_addr *addr, struct net_device *dev)
1334 {
1335 	struct inet6_dev *idev;
1336 	struct inet6_ifaddr *ifa;
1337 	int	onlink;
1338 
1339 	onlink = 0;
1340 	rcu_read_lock();
1341 	idev = __in6_dev_get(dev);
1342 	if (idev) {
1343 		read_lock_bh(&idev->lock);
1344 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1345 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1346 						   ifa->prefix_len);
1347 			if (onlink)
1348 				break;
1349 		}
1350 		read_unlock_bh(&idev->lock);
1351 	}
1352 	rcu_read_unlock();
1353 	return onlink;
1354 }
1355 
1356 EXPORT_SYMBOL(ipv6_chk_prefix);
1357 
1358 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1359 				     struct net_device *dev, int strict)
1360 {
1361 	struct inet6_ifaddr *ifp, *result = NULL;
1362 	unsigned int hash = ipv6_addr_hash(addr);
1363 	struct hlist_node *node;
1364 
1365 	rcu_read_lock_bh();
1366 	hlist_for_each_entry_rcu_bh(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1367 		if (!net_eq(dev_net(ifp->idev->dev), net))
1368 			continue;
1369 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1370 			if (dev == NULL || ifp->idev->dev == dev ||
1371 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1372 				result = ifp;
1373 				in6_ifa_hold(ifp);
1374 				break;
1375 			}
1376 		}
1377 	}
1378 	rcu_read_unlock_bh();
1379 
1380 	return result;
1381 }
1382 
1383 /* Gets referenced address, destroys ifaddr */
1384 
1385 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1386 {
1387 	if (ifp->flags&IFA_F_PERMANENT) {
1388 		spin_lock_bh(&ifp->lock);
1389 		addrconf_del_timer(ifp);
1390 		ifp->flags |= IFA_F_TENTATIVE;
1391 		if (dad_failed)
1392 			ifp->flags |= IFA_F_DADFAILED;
1393 		spin_unlock_bh(&ifp->lock);
1394 		if (dad_failed)
1395 			ipv6_ifa_notify(0, ifp);
1396 		in6_ifa_put(ifp);
1397 #ifdef CONFIG_IPV6_PRIVACY
1398 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1399 		struct inet6_ifaddr *ifpub;
1400 		spin_lock_bh(&ifp->lock);
1401 		ifpub = ifp->ifpub;
1402 		if (ifpub) {
1403 			in6_ifa_hold(ifpub);
1404 			spin_unlock_bh(&ifp->lock);
1405 			ipv6_create_tempaddr(ifpub, ifp);
1406 			in6_ifa_put(ifpub);
1407 		} else {
1408 			spin_unlock_bh(&ifp->lock);
1409 		}
1410 		ipv6_del_addr(ifp);
1411 #endif
1412 	} else
1413 		ipv6_del_addr(ifp);
1414 }
1415 
1416 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1417 {
1418 	int err = -ENOENT;
1419 
1420 	spin_lock(&ifp->state_lock);
1421 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1422 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1423 		err = 0;
1424 	}
1425 	spin_unlock(&ifp->state_lock);
1426 
1427 	return err;
1428 }
1429 
1430 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1431 {
1432 	struct inet6_dev *idev = ifp->idev;
1433 
1434 	if (addrconf_dad_end(ifp)) {
1435 		in6_ifa_put(ifp);
1436 		return;
1437 	}
1438 
1439 	if (net_ratelimit())
1440 		printk(KERN_INFO "%s: IPv6 duplicate address %pI6c detected!\n",
1441 			ifp->idev->dev->name, &ifp->addr);
1442 
1443 	if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1444 		struct in6_addr addr;
1445 
1446 		addr.s6_addr32[0] = htonl(0xfe800000);
1447 		addr.s6_addr32[1] = 0;
1448 
1449 		if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1450 		    ipv6_addr_equal(&ifp->addr, &addr)) {
1451 			/* DAD failed for link-local based on MAC address */
1452 			idev->cnf.disable_ipv6 = 1;
1453 
1454 			printk(KERN_INFO "%s: IPv6 being disabled!\n",
1455 				ifp->idev->dev->name);
1456 		}
1457 	}
1458 
1459 	addrconf_dad_stop(ifp, 1);
1460 }
1461 
1462 /* Join to solicited addr multicast group. */
1463 
1464 void addrconf_join_solict(struct net_device *dev, struct in6_addr *addr)
1465 {
1466 	struct in6_addr maddr;
1467 
1468 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1469 		return;
1470 
1471 	addrconf_addr_solict_mult(addr, &maddr);
1472 	ipv6_dev_mc_inc(dev, &maddr);
1473 }
1474 
1475 void addrconf_leave_solict(struct inet6_dev *idev, struct in6_addr *addr)
1476 {
1477 	struct in6_addr maddr;
1478 
1479 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1480 		return;
1481 
1482 	addrconf_addr_solict_mult(addr, &maddr);
1483 	__ipv6_dev_mc_dec(idev, &maddr);
1484 }
1485 
1486 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1487 {
1488 	struct in6_addr addr;
1489 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1490 	if (ipv6_addr_any(&addr))
1491 		return;
1492 	ipv6_dev_ac_inc(ifp->idev->dev, &addr);
1493 }
1494 
1495 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1496 {
1497 	struct in6_addr addr;
1498 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1499 	if (ipv6_addr_any(&addr))
1500 		return;
1501 	__ipv6_dev_ac_dec(ifp->idev, &addr);
1502 }
1503 
1504 static int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
1505 {
1506 	if (dev->addr_len != ETH_ALEN)
1507 		return -1;
1508 	memcpy(eui, dev->dev_addr, 3);
1509 	memcpy(eui + 5, dev->dev_addr + 3, 3);
1510 
1511 	/*
1512 	 * The zSeries OSA network cards can be shared among various
1513 	 * OS instances, but the OSA cards have only one MAC address.
1514 	 * This leads to duplicate address conflicts in conjunction
1515 	 * with IPv6 if more than one instance uses the same card.
1516 	 *
1517 	 * The driver for these cards can deliver a unique 16-bit
1518 	 * identifier for each instance sharing the same card.  It is
1519 	 * placed instead of 0xFFFE in the interface identifier.  The
1520 	 * "u" bit of the interface identifier is not inverted in this
1521 	 * case.  Hence the resulting interface identifier has local
1522 	 * scope according to RFC2373.
1523 	 */
1524 	if (dev->dev_id) {
1525 		eui[3] = (dev->dev_id >> 8) & 0xFF;
1526 		eui[4] = dev->dev_id & 0xFF;
1527 	} else {
1528 		eui[3] = 0xFF;
1529 		eui[4] = 0xFE;
1530 		eui[0] ^= 2;
1531 	}
1532 	return 0;
1533 }
1534 
1535 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
1536 {
1537 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
1538 	if (dev->addr_len != ARCNET_ALEN)
1539 		return -1;
1540 	memset(eui, 0, 7);
1541 	eui[7] = *(u8*)dev->dev_addr;
1542 	return 0;
1543 }
1544 
1545 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
1546 {
1547 	if (dev->addr_len != INFINIBAND_ALEN)
1548 		return -1;
1549 	memcpy(eui, dev->dev_addr + 12, 8);
1550 	eui[0] |= 2;
1551 	return 0;
1552 }
1553 
1554 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
1555 {
1556 	if (addr == 0)
1557 		return -1;
1558 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
1559 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
1560 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
1561 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
1562 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
1563 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
1564 	eui[1] = 0;
1565 	eui[2] = 0x5E;
1566 	eui[3] = 0xFE;
1567 	memcpy(eui + 4, &addr, 4);
1568 	return 0;
1569 }
1570 
1571 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
1572 {
1573 	if (dev->priv_flags & IFF_ISATAP)
1574 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1575 	return -1;
1576 }
1577 
1578 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
1579 {
1580 	switch (dev->type) {
1581 	case ARPHRD_ETHER:
1582 	case ARPHRD_FDDI:
1583 	case ARPHRD_IEEE802_TR:
1584 		return addrconf_ifid_eui48(eui, dev);
1585 	case ARPHRD_ARCNET:
1586 		return addrconf_ifid_arcnet(eui, dev);
1587 	case ARPHRD_INFINIBAND:
1588 		return addrconf_ifid_infiniband(eui, dev);
1589 	case ARPHRD_SIT:
1590 		return addrconf_ifid_sit(eui, dev);
1591 	}
1592 	return -1;
1593 }
1594 
1595 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
1596 {
1597 	int err = -1;
1598 	struct inet6_ifaddr *ifp;
1599 
1600 	read_lock_bh(&idev->lock);
1601 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
1602 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
1603 			memcpy(eui, ifp->addr.s6_addr+8, 8);
1604 			err = 0;
1605 			break;
1606 		}
1607 	}
1608 	read_unlock_bh(&idev->lock);
1609 	return err;
1610 }
1611 
1612 #ifdef CONFIG_IPV6_PRIVACY
1613 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
1614 static int __ipv6_regen_rndid(struct inet6_dev *idev)
1615 {
1616 regen:
1617 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
1618 	idev->rndid[0] &= ~0x02;
1619 
1620 	/*
1621 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
1622 	 * check if generated address is not inappropriate
1623 	 *
1624 	 *  - Reserved subnet anycast (RFC 2526)
1625 	 *	11111101 11....11 1xxxxxxx
1626 	 *  - ISATAP (RFC4214) 6.1
1627 	 *	00-00-5E-FE-xx-xx-xx-xx
1628 	 *  - value 0
1629 	 *  - XXX: already assigned to an address on the device
1630 	 */
1631 	if (idev->rndid[0] == 0xfd &&
1632 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
1633 	    (idev->rndid[7]&0x80))
1634 		goto regen;
1635 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
1636 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
1637 			goto regen;
1638 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
1639 			goto regen;
1640 	}
1641 
1642 	return 0;
1643 }
1644 
1645 static void ipv6_regen_rndid(unsigned long data)
1646 {
1647 	struct inet6_dev *idev = (struct inet6_dev *) data;
1648 	unsigned long expires;
1649 
1650 	rcu_read_lock_bh();
1651 	write_lock_bh(&idev->lock);
1652 
1653 	if (idev->dead)
1654 		goto out;
1655 
1656 	if (__ipv6_regen_rndid(idev) < 0)
1657 		goto out;
1658 
1659 	expires = jiffies +
1660 		idev->cnf.temp_prefered_lft * HZ -
1661 		idev->cnf.regen_max_retry * idev->cnf.dad_transmits * idev->nd_parms->retrans_time -
1662 		idev->cnf.max_desync_factor * HZ;
1663 	if (time_before(expires, jiffies)) {
1664 		printk(KERN_WARNING
1665 			"ipv6_regen_rndid(): too short regeneration interval; timer disabled for %s.\n",
1666 			idev->dev->name);
1667 		goto out;
1668 	}
1669 
1670 	if (!mod_timer(&idev->regen_timer, expires))
1671 		in6_dev_hold(idev);
1672 
1673 out:
1674 	write_unlock_bh(&idev->lock);
1675 	rcu_read_unlock_bh();
1676 	in6_dev_put(idev);
1677 }
1678 
1679 static int __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr) {
1680 	int ret = 0;
1681 
1682 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
1683 		ret = __ipv6_regen_rndid(idev);
1684 	return ret;
1685 }
1686 #endif
1687 
1688 /*
1689  *	Add prefix route.
1690  */
1691 
1692 static void
1693 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
1694 		      unsigned long expires, u32 flags)
1695 {
1696 	struct fib6_config cfg = {
1697 		.fc_table = RT6_TABLE_PREFIX,
1698 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1699 		.fc_ifindex = dev->ifindex,
1700 		.fc_expires = expires,
1701 		.fc_dst_len = plen,
1702 		.fc_flags = RTF_UP | flags,
1703 		.fc_nlinfo.nl_net = dev_net(dev),
1704 		.fc_protocol = RTPROT_KERNEL,
1705 	};
1706 
1707 	ipv6_addr_copy(&cfg.fc_dst, pfx);
1708 
1709 	/* Prevent useless cloning on PtP SIT.
1710 	   This thing is done here expecting that the whole
1711 	   class of non-broadcast devices need not cloning.
1712 	 */
1713 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
1714 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
1715 		cfg.fc_flags |= RTF_NONEXTHOP;
1716 #endif
1717 
1718 	ip6_route_add(&cfg);
1719 }
1720 
1721 /* Create "default" multicast route to the interface */
1722 
1723 static void addrconf_add_mroute(struct net_device *dev)
1724 {
1725 	struct fib6_config cfg = {
1726 		.fc_table = RT6_TABLE_LOCAL,
1727 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1728 		.fc_ifindex = dev->ifindex,
1729 		.fc_dst_len = 8,
1730 		.fc_flags = RTF_UP,
1731 		.fc_nlinfo.nl_net = dev_net(dev),
1732 	};
1733 
1734 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
1735 
1736 	ip6_route_add(&cfg);
1737 }
1738 
1739 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
1740 static void sit_route_add(struct net_device *dev)
1741 {
1742 	struct fib6_config cfg = {
1743 		.fc_table = RT6_TABLE_MAIN,
1744 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1745 		.fc_ifindex = dev->ifindex,
1746 		.fc_dst_len = 96,
1747 		.fc_flags = RTF_UP | RTF_NONEXTHOP,
1748 		.fc_nlinfo.nl_net = dev_net(dev),
1749 	};
1750 
1751 	/* prefix length - 96 bits "::d.d.d.d" */
1752 	ip6_route_add(&cfg);
1753 }
1754 #endif
1755 
1756 static void addrconf_add_lroute(struct net_device *dev)
1757 {
1758 	struct in6_addr addr;
1759 
1760 	ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
1761 	addrconf_prefix_route(&addr, 64, dev, 0, 0);
1762 }
1763 
1764 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
1765 {
1766 	struct inet6_dev *idev;
1767 
1768 	ASSERT_RTNL();
1769 
1770 	idev = ipv6_find_idev(dev);
1771 	if (!idev)
1772 		return ERR_PTR(-ENOBUFS);
1773 
1774 	if (idev->cnf.disable_ipv6)
1775 		return ERR_PTR(-EACCES);
1776 
1777 	/* Add default multicast route */
1778 	addrconf_add_mroute(dev);
1779 
1780 	/* Add link local route */
1781 	addrconf_add_lroute(dev);
1782 	return idev;
1783 }
1784 
1785 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len)
1786 {
1787 	struct prefix_info *pinfo;
1788 	__u32 valid_lft;
1789 	__u32 prefered_lft;
1790 	int addr_type;
1791 	struct inet6_dev *in6_dev;
1792 	struct net *net = dev_net(dev);
1793 
1794 	pinfo = (struct prefix_info *) opt;
1795 
1796 	if (len < sizeof(struct prefix_info)) {
1797 		ADBG(("addrconf: prefix option too short\n"));
1798 		return;
1799 	}
1800 
1801 	/*
1802 	 *	Validation checks ([ADDRCONF], page 19)
1803 	 */
1804 
1805 	addr_type = ipv6_addr_type(&pinfo->prefix);
1806 
1807 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
1808 		return;
1809 
1810 	valid_lft = ntohl(pinfo->valid);
1811 	prefered_lft = ntohl(pinfo->prefered);
1812 
1813 	if (prefered_lft > valid_lft) {
1814 		if (net_ratelimit())
1815 			printk(KERN_WARNING "addrconf: prefix option has invalid lifetime\n");
1816 		return;
1817 	}
1818 
1819 	in6_dev = in6_dev_get(dev);
1820 
1821 	if (in6_dev == NULL) {
1822 		if (net_ratelimit())
1823 			printk(KERN_DEBUG "addrconf: device %s not configured\n", dev->name);
1824 		return;
1825 	}
1826 
1827 	/*
1828 	 *	Two things going on here:
1829 	 *	1) Add routes for on-link prefixes
1830 	 *	2) Configure prefixes with the auto flag set
1831 	 */
1832 
1833 	if (pinfo->onlink) {
1834 		struct rt6_info *rt;
1835 		unsigned long rt_expires;
1836 
1837 		/* Avoid arithmetic overflow. Really, we could
1838 		 * save rt_expires in seconds, likely valid_lft,
1839 		 * but it would require division in fib gc, that it
1840 		 * not good.
1841 		 */
1842 		if (HZ > USER_HZ)
1843 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
1844 		else
1845 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
1846 
1847 		if (addrconf_finite_timeout(rt_expires))
1848 			rt_expires *= HZ;
1849 
1850 		rt = rt6_lookup(net, &pinfo->prefix, NULL,
1851 				dev->ifindex, 1);
1852 
1853 		if (rt && addrconf_is_prefix_route(rt)) {
1854 			/* Autoconf prefix route */
1855 			if (valid_lft == 0) {
1856 				ip6_del_rt(rt);
1857 				rt = NULL;
1858 			} else if (addrconf_finite_timeout(rt_expires)) {
1859 				/* not infinity */
1860 				rt->rt6i_expires = jiffies + rt_expires;
1861 				rt->rt6i_flags |= RTF_EXPIRES;
1862 			} else {
1863 				rt->rt6i_flags &= ~RTF_EXPIRES;
1864 				rt->rt6i_expires = 0;
1865 			}
1866 		} else if (valid_lft) {
1867 			clock_t expires = 0;
1868 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
1869 			if (addrconf_finite_timeout(rt_expires)) {
1870 				/* not infinity */
1871 				flags |= RTF_EXPIRES;
1872 				expires = jiffies_to_clock_t(rt_expires);
1873 			}
1874 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
1875 					      dev, expires, flags);
1876 		}
1877 		if (rt)
1878 			dst_release(&rt->dst);
1879 	}
1880 
1881 	/* Try to figure out our local address for this prefix */
1882 
1883 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
1884 		struct inet6_ifaddr * ifp;
1885 		struct in6_addr addr;
1886 		int create = 0, update_lft = 0;
1887 
1888 		if (pinfo->prefix_len == 64) {
1889 			memcpy(&addr, &pinfo->prefix, 8);
1890 			if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
1891 			    ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
1892 				in6_dev_put(in6_dev);
1893 				return;
1894 			}
1895 			goto ok;
1896 		}
1897 		if (net_ratelimit())
1898 			printk(KERN_DEBUG "IPv6 addrconf: prefix with wrong length %d\n",
1899 			       pinfo->prefix_len);
1900 		in6_dev_put(in6_dev);
1901 		return;
1902 
1903 ok:
1904 
1905 		ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
1906 
1907 		if (ifp == NULL && valid_lft) {
1908 			int max_addresses = in6_dev->cnf.max_addresses;
1909 			u32 addr_flags = 0;
1910 
1911 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1912 			if (in6_dev->cnf.optimistic_dad &&
1913 			    !net->ipv6.devconf_all->forwarding)
1914 				addr_flags = IFA_F_OPTIMISTIC;
1915 #endif
1916 
1917 			/* Do not allow to create too much of autoconfigured
1918 			 * addresses; this would be too easy way to crash kernel.
1919 			 */
1920 			if (!max_addresses ||
1921 			    ipv6_count_addresses(in6_dev) < max_addresses)
1922 				ifp = ipv6_add_addr(in6_dev, &addr, pinfo->prefix_len,
1923 						    addr_type&IPV6_ADDR_SCOPE_MASK,
1924 						    addr_flags);
1925 
1926 			if (!ifp || IS_ERR(ifp)) {
1927 				in6_dev_put(in6_dev);
1928 				return;
1929 			}
1930 
1931 			update_lft = create = 1;
1932 			ifp->cstamp = jiffies;
1933 			addrconf_dad_start(ifp, RTF_ADDRCONF|RTF_PREFIX_RT);
1934 		}
1935 
1936 		if (ifp) {
1937 			int flags;
1938 			unsigned long now;
1939 #ifdef CONFIG_IPV6_PRIVACY
1940 			struct inet6_ifaddr *ift;
1941 #endif
1942 			u32 stored_lft;
1943 
1944 			/* update lifetime (RFC2462 5.5.3 e) */
1945 			spin_lock(&ifp->lock);
1946 			now = jiffies;
1947 			if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
1948 				stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
1949 			else
1950 				stored_lft = 0;
1951 			if (!update_lft && stored_lft) {
1952 				if (valid_lft > MIN_VALID_LIFETIME ||
1953 				    valid_lft > stored_lft)
1954 					update_lft = 1;
1955 				else if (stored_lft <= MIN_VALID_LIFETIME) {
1956 					/* valid_lft <= stored_lft is always true */
1957 					/*
1958 					 * RFC 4862 Section 5.5.3e:
1959 					 * "Note that the preferred lifetime of
1960 					 *  the corresponding address is always
1961 					 *  reset to the Preferred Lifetime in
1962 					 *  the received Prefix Information
1963 					 *  option, regardless of whether the
1964 					 *  valid lifetime is also reset or
1965 					 *  ignored."
1966 					 *
1967 					 *  So if the preferred lifetime in
1968 					 *  this advertisement is different
1969 					 *  than what we have stored, but the
1970 					 *  valid lifetime is invalid, just
1971 					 *  reset prefered_lft.
1972 					 *
1973 					 *  We must set the valid lifetime
1974 					 *  to the stored lifetime since we'll
1975 					 *  be updating the timestamp below,
1976 					 *  else we'll set it back to the
1977 					 *  minumum.
1978 					 */
1979 					if (prefered_lft != ifp->prefered_lft) {
1980 						valid_lft = stored_lft;
1981 						update_lft = 1;
1982 					}
1983 				} else {
1984 					valid_lft = MIN_VALID_LIFETIME;
1985 					if (valid_lft < prefered_lft)
1986 						prefered_lft = valid_lft;
1987 					update_lft = 1;
1988 				}
1989 			}
1990 
1991 			if (update_lft) {
1992 				ifp->valid_lft = valid_lft;
1993 				ifp->prefered_lft = prefered_lft;
1994 				ifp->tstamp = now;
1995 				flags = ifp->flags;
1996 				ifp->flags &= ~IFA_F_DEPRECATED;
1997 				spin_unlock(&ifp->lock);
1998 
1999 				if (!(flags&IFA_F_TENTATIVE))
2000 					ipv6_ifa_notify(0, ifp);
2001 			} else
2002 				spin_unlock(&ifp->lock);
2003 
2004 #ifdef CONFIG_IPV6_PRIVACY
2005 			read_lock_bh(&in6_dev->lock);
2006 			/* update all temporary addresses in the list */
2007 			list_for_each_entry(ift, &in6_dev->tempaddr_list, tmp_list) {
2008 				/*
2009 				 * When adjusting the lifetimes of an existing
2010 				 * temporary address, only lower the lifetimes.
2011 				 * Implementations must not increase the
2012 				 * lifetimes of an existing temporary address
2013 				 * when processing a Prefix Information Option.
2014 				 */
2015 				if (ifp != ift->ifpub)
2016 					continue;
2017 
2018 				spin_lock(&ift->lock);
2019 				flags = ift->flags;
2020 				if (ift->valid_lft > valid_lft &&
2021 				    ift->valid_lft - valid_lft > (jiffies - ift->tstamp) / HZ)
2022 					ift->valid_lft = valid_lft + (jiffies - ift->tstamp) / HZ;
2023 				if (ift->prefered_lft > prefered_lft &&
2024 				    ift->prefered_lft - prefered_lft > (jiffies - ift->tstamp) / HZ)
2025 					ift->prefered_lft = prefered_lft + (jiffies - ift->tstamp) / HZ;
2026 				spin_unlock(&ift->lock);
2027 				if (!(flags&IFA_F_TENTATIVE))
2028 					ipv6_ifa_notify(0, ift);
2029 			}
2030 
2031 			if ((create || list_empty(&in6_dev->tempaddr_list)) && in6_dev->cnf.use_tempaddr > 0) {
2032 				/*
2033 				 * When a new public address is created as described in [ADDRCONF],
2034 				 * also create a new temporary address. Also create a temporary
2035 				 * address if it's enabled but no temporary address currently exists.
2036 				 */
2037 				read_unlock_bh(&in6_dev->lock);
2038 				ipv6_create_tempaddr(ifp, NULL);
2039 			} else {
2040 				read_unlock_bh(&in6_dev->lock);
2041 			}
2042 #endif
2043 			in6_ifa_put(ifp);
2044 			addrconf_verify(0);
2045 		}
2046 	}
2047 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2048 	in6_dev_put(in6_dev);
2049 }
2050 
2051 /*
2052  *	Set destination address.
2053  *	Special case for SIT interfaces where we create a new "virtual"
2054  *	device.
2055  */
2056 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2057 {
2058 	struct in6_ifreq ireq;
2059 	struct net_device *dev;
2060 	int err = -EINVAL;
2061 
2062 	rtnl_lock();
2063 
2064 	err = -EFAULT;
2065 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2066 		goto err_exit;
2067 
2068 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2069 
2070 	err = -ENODEV;
2071 	if (dev == NULL)
2072 		goto err_exit;
2073 
2074 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
2075 	if (dev->type == ARPHRD_SIT) {
2076 		const struct net_device_ops *ops = dev->netdev_ops;
2077 		struct ifreq ifr;
2078 		struct ip_tunnel_parm p;
2079 
2080 		err = -EADDRNOTAVAIL;
2081 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2082 			goto err_exit;
2083 
2084 		memset(&p, 0, sizeof(p));
2085 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2086 		p.iph.saddr = 0;
2087 		p.iph.version = 4;
2088 		p.iph.ihl = 5;
2089 		p.iph.protocol = IPPROTO_IPV6;
2090 		p.iph.ttl = 64;
2091 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2092 
2093 		if (ops->ndo_do_ioctl) {
2094 			mm_segment_t oldfs = get_fs();
2095 
2096 			set_fs(KERNEL_DS);
2097 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2098 			set_fs(oldfs);
2099 		} else
2100 			err = -EOPNOTSUPP;
2101 
2102 		if (err == 0) {
2103 			err = -ENOBUFS;
2104 			dev = __dev_get_by_name(net, p.name);
2105 			if (!dev)
2106 				goto err_exit;
2107 			err = dev_open(dev);
2108 		}
2109 	}
2110 #endif
2111 
2112 err_exit:
2113 	rtnl_unlock();
2114 	return err;
2115 }
2116 
2117 /*
2118  *	Manual configuration of address on an interface
2119  */
2120 static int inet6_addr_add(struct net *net, int ifindex, struct in6_addr *pfx,
2121 			  unsigned int plen, __u8 ifa_flags, __u32 prefered_lft,
2122 			  __u32 valid_lft)
2123 {
2124 	struct inet6_ifaddr *ifp;
2125 	struct inet6_dev *idev;
2126 	struct net_device *dev;
2127 	int scope;
2128 	u32 flags;
2129 	clock_t expires;
2130 	unsigned long timeout;
2131 
2132 	ASSERT_RTNL();
2133 
2134 	if (plen > 128)
2135 		return -EINVAL;
2136 
2137 	/* check the lifetime */
2138 	if (!valid_lft || prefered_lft > valid_lft)
2139 		return -EINVAL;
2140 
2141 	dev = __dev_get_by_index(net, ifindex);
2142 	if (!dev)
2143 		return -ENODEV;
2144 
2145 	idev = addrconf_add_dev(dev);
2146 	if (IS_ERR(idev))
2147 		return PTR_ERR(idev);
2148 
2149 	scope = ipv6_addr_scope(pfx);
2150 
2151 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2152 	if (addrconf_finite_timeout(timeout)) {
2153 		expires = jiffies_to_clock_t(timeout * HZ);
2154 		valid_lft = timeout;
2155 		flags = RTF_EXPIRES;
2156 	} else {
2157 		expires = 0;
2158 		flags = 0;
2159 		ifa_flags |= IFA_F_PERMANENT;
2160 	}
2161 
2162 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2163 	if (addrconf_finite_timeout(timeout)) {
2164 		if (timeout == 0)
2165 			ifa_flags |= IFA_F_DEPRECATED;
2166 		prefered_lft = timeout;
2167 	}
2168 
2169 	ifp = ipv6_add_addr(idev, pfx, plen, scope, ifa_flags);
2170 
2171 	if (!IS_ERR(ifp)) {
2172 		spin_lock_bh(&ifp->lock);
2173 		ifp->valid_lft = valid_lft;
2174 		ifp->prefered_lft = prefered_lft;
2175 		ifp->tstamp = jiffies;
2176 		spin_unlock_bh(&ifp->lock);
2177 
2178 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2179 				      expires, flags);
2180 		/*
2181 		 * Note that section 3.1 of RFC 4429 indicates
2182 		 * that the Optimistic flag should not be set for
2183 		 * manually configured addresses
2184 		 */
2185 		addrconf_dad_start(ifp, 0);
2186 		in6_ifa_put(ifp);
2187 		addrconf_verify(0);
2188 		return 0;
2189 	}
2190 
2191 	return PTR_ERR(ifp);
2192 }
2193 
2194 static int inet6_addr_del(struct net *net, int ifindex, struct in6_addr *pfx,
2195 			  unsigned int plen)
2196 {
2197 	struct inet6_ifaddr *ifp;
2198 	struct inet6_dev *idev;
2199 	struct net_device *dev;
2200 
2201 	if (plen > 128)
2202 		return -EINVAL;
2203 
2204 	dev = __dev_get_by_index(net, ifindex);
2205 	if (!dev)
2206 		return -ENODEV;
2207 
2208 	if ((idev = __in6_dev_get(dev)) == NULL)
2209 		return -ENXIO;
2210 
2211 	read_lock_bh(&idev->lock);
2212 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2213 		if (ifp->prefix_len == plen &&
2214 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2215 			in6_ifa_hold(ifp);
2216 			read_unlock_bh(&idev->lock);
2217 
2218 			ipv6_del_addr(ifp);
2219 
2220 			/* If the last address is deleted administratively,
2221 			   disable IPv6 on this interface.
2222 			 */
2223 			if (list_empty(&idev->addr_list))
2224 				addrconf_ifdown(idev->dev, 1);
2225 			return 0;
2226 		}
2227 	}
2228 	read_unlock_bh(&idev->lock);
2229 	return -EADDRNOTAVAIL;
2230 }
2231 
2232 
2233 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2234 {
2235 	struct in6_ifreq ireq;
2236 	int err;
2237 
2238 	if (!capable(CAP_NET_ADMIN))
2239 		return -EPERM;
2240 
2241 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2242 		return -EFAULT;
2243 
2244 	rtnl_lock();
2245 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2246 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2247 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2248 	rtnl_unlock();
2249 	return err;
2250 }
2251 
2252 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2253 {
2254 	struct in6_ifreq ireq;
2255 	int err;
2256 
2257 	if (!capable(CAP_NET_ADMIN))
2258 		return -EPERM;
2259 
2260 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2261 		return -EFAULT;
2262 
2263 	rtnl_lock();
2264 	err = inet6_addr_del(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2265 			     ireq.ifr6_prefixlen);
2266 	rtnl_unlock();
2267 	return err;
2268 }
2269 
2270 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2271 		     int plen, int scope)
2272 {
2273 	struct inet6_ifaddr *ifp;
2274 
2275 	ifp = ipv6_add_addr(idev, addr, plen, scope, IFA_F_PERMANENT);
2276 	if (!IS_ERR(ifp)) {
2277 		spin_lock_bh(&ifp->lock);
2278 		ifp->flags &= ~IFA_F_TENTATIVE;
2279 		spin_unlock_bh(&ifp->lock);
2280 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2281 		in6_ifa_put(ifp);
2282 	}
2283 }
2284 
2285 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
2286 static void sit_add_v4_addrs(struct inet6_dev *idev)
2287 {
2288 	struct in6_addr addr;
2289 	struct net_device *dev;
2290 	struct net *net = dev_net(idev->dev);
2291 	int scope;
2292 
2293 	ASSERT_RTNL();
2294 
2295 	memset(&addr, 0, sizeof(struct in6_addr));
2296 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2297 
2298 	if (idev->dev->flags&IFF_POINTOPOINT) {
2299 		addr.s6_addr32[0] = htonl(0xfe800000);
2300 		scope = IFA_LINK;
2301 	} else {
2302 		scope = IPV6_ADDR_COMPATv4;
2303 	}
2304 
2305 	if (addr.s6_addr32[3]) {
2306 		add_addr(idev, &addr, 128, scope);
2307 		return;
2308 	}
2309 
2310 	for_each_netdev(net, dev) {
2311 		struct in_device * in_dev = __in_dev_get_rtnl(dev);
2312 		if (in_dev && (dev->flags & IFF_UP)) {
2313 			struct in_ifaddr * ifa;
2314 
2315 			int flag = scope;
2316 
2317 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2318 				int plen;
2319 
2320 				addr.s6_addr32[3] = ifa->ifa_local;
2321 
2322 				if (ifa->ifa_scope == RT_SCOPE_LINK)
2323 					continue;
2324 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2325 					if (idev->dev->flags&IFF_POINTOPOINT)
2326 						continue;
2327 					flag |= IFA_HOST;
2328 				}
2329 				if (idev->dev->flags&IFF_POINTOPOINT)
2330 					plen = 64;
2331 				else
2332 					plen = 96;
2333 
2334 				add_addr(idev, &addr, plen, flag);
2335 			}
2336 		}
2337 	}
2338 }
2339 #endif
2340 
2341 static void init_loopback(struct net_device *dev)
2342 {
2343 	struct inet6_dev  *idev;
2344 
2345 	/* ::1 */
2346 
2347 	ASSERT_RTNL();
2348 
2349 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2350 		printk(KERN_DEBUG "init loopback: add_dev failed\n");
2351 		return;
2352 	}
2353 
2354 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2355 }
2356 
2357 static void addrconf_add_linklocal(struct inet6_dev *idev, struct in6_addr *addr)
2358 {
2359 	struct inet6_ifaddr * ifp;
2360 	u32 addr_flags = IFA_F_PERMANENT;
2361 
2362 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2363 	if (idev->cnf.optimistic_dad &&
2364 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
2365 		addr_flags |= IFA_F_OPTIMISTIC;
2366 #endif
2367 
2368 
2369 	ifp = ipv6_add_addr(idev, addr, 64, IFA_LINK, addr_flags);
2370 	if (!IS_ERR(ifp)) {
2371 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
2372 		addrconf_dad_start(ifp, 0);
2373 		in6_ifa_put(ifp);
2374 	}
2375 }
2376 
2377 static void addrconf_dev_config(struct net_device *dev)
2378 {
2379 	struct in6_addr addr;
2380 	struct inet6_dev    * idev;
2381 
2382 	ASSERT_RTNL();
2383 
2384 	if ((dev->type != ARPHRD_ETHER) &&
2385 	    (dev->type != ARPHRD_FDDI) &&
2386 	    (dev->type != ARPHRD_IEEE802_TR) &&
2387 	    (dev->type != ARPHRD_ARCNET) &&
2388 	    (dev->type != ARPHRD_INFINIBAND)) {
2389 		/* Alas, we support only Ethernet autoconfiguration. */
2390 		return;
2391 	}
2392 
2393 	idev = addrconf_add_dev(dev);
2394 	if (IS_ERR(idev))
2395 		return;
2396 
2397 	memset(&addr, 0, sizeof(struct in6_addr));
2398 	addr.s6_addr32[0] = htonl(0xFE800000);
2399 
2400 	if (ipv6_generate_eui64(addr.s6_addr + 8, dev) == 0)
2401 		addrconf_add_linklocal(idev, &addr);
2402 }
2403 
2404 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
2405 static void addrconf_sit_config(struct net_device *dev)
2406 {
2407 	struct inet6_dev *idev;
2408 
2409 	ASSERT_RTNL();
2410 
2411 	/*
2412 	 * Configure the tunnel with one of our IPv4
2413 	 * addresses... we should configure all of
2414 	 * our v4 addrs in the tunnel
2415 	 */
2416 
2417 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2418 		printk(KERN_DEBUG "init sit: add_dev failed\n");
2419 		return;
2420 	}
2421 
2422 	if (dev->priv_flags & IFF_ISATAP) {
2423 		struct in6_addr addr;
2424 
2425 		ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2426 		addrconf_prefix_route(&addr, 64, dev, 0, 0);
2427 		if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2428 			addrconf_add_linklocal(idev, &addr);
2429 		return;
2430 	}
2431 
2432 	sit_add_v4_addrs(idev);
2433 
2434 	if (dev->flags&IFF_POINTOPOINT) {
2435 		addrconf_add_mroute(dev);
2436 		addrconf_add_lroute(dev);
2437 	} else
2438 		sit_route_add(dev);
2439 }
2440 #endif
2441 
2442 static inline int
2443 ipv6_inherit_linklocal(struct inet6_dev *idev, struct net_device *link_dev)
2444 {
2445 	struct in6_addr lladdr;
2446 
2447 	if (!ipv6_get_lladdr(link_dev, &lladdr, IFA_F_TENTATIVE)) {
2448 		addrconf_add_linklocal(idev, &lladdr);
2449 		return 0;
2450 	}
2451 	return -1;
2452 }
2453 
2454 static void ip6_tnl_add_linklocal(struct inet6_dev *idev)
2455 {
2456 	struct net_device *link_dev;
2457 	struct net *net = dev_net(idev->dev);
2458 
2459 	/* first try to inherit the link-local address from the link device */
2460 	if (idev->dev->iflink &&
2461 	    (link_dev = __dev_get_by_index(net, idev->dev->iflink))) {
2462 		if (!ipv6_inherit_linklocal(idev, link_dev))
2463 			return;
2464 	}
2465 	/* then try to inherit it from any device */
2466 	for_each_netdev(net, link_dev) {
2467 		if (!ipv6_inherit_linklocal(idev, link_dev))
2468 			return;
2469 	}
2470 	printk(KERN_DEBUG "init ip6-ip6: add_linklocal failed\n");
2471 }
2472 
2473 /*
2474  * Autoconfigure tunnel with a link-local address so routing protocols,
2475  * DHCPv6, MLD etc. can be run over the virtual link
2476  */
2477 
2478 static void addrconf_ip6_tnl_config(struct net_device *dev)
2479 {
2480 	struct inet6_dev *idev;
2481 
2482 	ASSERT_RTNL();
2483 
2484 	idev = addrconf_add_dev(dev);
2485 	if (IS_ERR(idev)) {
2486 		printk(KERN_DEBUG "init ip6-ip6: add_dev failed\n");
2487 		return;
2488 	}
2489 	ip6_tnl_add_linklocal(idev);
2490 }
2491 
2492 static int addrconf_notify(struct notifier_block *this, unsigned long event,
2493 			   void * data)
2494 {
2495 	struct net_device *dev = (struct net_device *) data;
2496 	struct inet6_dev *idev = __in6_dev_get(dev);
2497 	int run_pending = 0;
2498 	int err;
2499 
2500 	switch (event) {
2501 	case NETDEV_REGISTER:
2502 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2503 			idev = ipv6_add_dev(dev);
2504 			if (!idev)
2505 				return notifier_from_errno(-ENOMEM);
2506 		}
2507 		break;
2508 
2509 	case NETDEV_UP:
2510 	case NETDEV_CHANGE:
2511 		if (dev->flags & IFF_SLAVE)
2512 			break;
2513 
2514 		if (event == NETDEV_UP) {
2515 			if (!addrconf_qdisc_ok(dev)) {
2516 				/* device is not ready yet. */
2517 				printk(KERN_INFO
2518 					"ADDRCONF(NETDEV_UP): %s: "
2519 					"link is not ready\n",
2520 					dev->name);
2521 				break;
2522 			}
2523 
2524 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
2525 				idev = ipv6_add_dev(dev);
2526 
2527 			if (idev) {
2528 				idev->if_flags |= IF_READY;
2529 				run_pending = 1;
2530 			}
2531 		} else {
2532 			if (!addrconf_qdisc_ok(dev)) {
2533 				/* device is still not ready. */
2534 				break;
2535 			}
2536 
2537 			if (idev) {
2538 				if (idev->if_flags & IF_READY)
2539 					/* device is already configured. */
2540 					break;
2541 				idev->if_flags |= IF_READY;
2542 			}
2543 
2544 			printk(KERN_INFO
2545 					"ADDRCONF(NETDEV_CHANGE): %s: "
2546 					"link becomes ready\n",
2547 					dev->name);
2548 
2549 			run_pending = 1;
2550 		}
2551 
2552 		switch (dev->type) {
2553 #if defined(CONFIG_IPV6_SIT) || defined(CONFIG_IPV6_SIT_MODULE)
2554 		case ARPHRD_SIT:
2555 			addrconf_sit_config(dev);
2556 			break;
2557 #endif
2558 		case ARPHRD_TUNNEL6:
2559 			addrconf_ip6_tnl_config(dev);
2560 			break;
2561 		case ARPHRD_LOOPBACK:
2562 			init_loopback(dev);
2563 			break;
2564 
2565 		default:
2566 			addrconf_dev_config(dev);
2567 			break;
2568 		}
2569 
2570 		if (idev) {
2571 			if (run_pending)
2572 				addrconf_dad_run(idev);
2573 
2574 			/*
2575 			 * If the MTU changed during the interface down,
2576 			 * when the interface up, the changed MTU must be
2577 			 * reflected in the idev as well as routers.
2578 			 */
2579 			if (idev->cnf.mtu6 != dev->mtu &&
2580 			    dev->mtu >= IPV6_MIN_MTU) {
2581 				rt6_mtu_change(dev, dev->mtu);
2582 				idev->cnf.mtu6 = dev->mtu;
2583 			}
2584 			idev->tstamp = jiffies;
2585 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
2586 
2587 			/*
2588 			 * If the changed mtu during down is lower than
2589 			 * IPV6_MIN_MTU stop IPv6 on this interface.
2590 			 */
2591 			if (dev->mtu < IPV6_MIN_MTU)
2592 				addrconf_ifdown(dev, 1);
2593 		}
2594 		break;
2595 
2596 	case NETDEV_CHANGEMTU:
2597 		if (idev && dev->mtu >= IPV6_MIN_MTU) {
2598 			rt6_mtu_change(dev, dev->mtu);
2599 			idev->cnf.mtu6 = dev->mtu;
2600 			break;
2601 		}
2602 
2603 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2604 			idev = ipv6_add_dev(dev);
2605 			if (idev)
2606 				break;
2607 		}
2608 
2609 		/*
2610 		 * MTU falled under IPV6_MIN_MTU.
2611 		 * Stop IPv6 on this interface.
2612 		 */
2613 
2614 	case NETDEV_DOWN:
2615 	case NETDEV_UNREGISTER:
2616 		/*
2617 		 *	Remove all addresses from this interface.
2618 		 */
2619 		addrconf_ifdown(dev, event != NETDEV_DOWN);
2620 		break;
2621 
2622 	case NETDEV_CHANGENAME:
2623 		if (idev) {
2624 			snmp6_unregister_dev(idev);
2625 			addrconf_sysctl_unregister(idev);
2626 			addrconf_sysctl_register(idev);
2627 			err = snmp6_register_dev(idev);
2628 			if (err)
2629 				return notifier_from_errno(err);
2630 		}
2631 		break;
2632 
2633 	case NETDEV_PRE_TYPE_CHANGE:
2634 	case NETDEV_POST_TYPE_CHANGE:
2635 		addrconf_type_change(dev, event);
2636 		break;
2637 	}
2638 
2639 	return NOTIFY_OK;
2640 }
2641 
2642 /*
2643  *	addrconf module should be notified of a device going up
2644  */
2645 static struct notifier_block ipv6_dev_notf = {
2646 	.notifier_call = addrconf_notify,
2647 };
2648 
2649 static void addrconf_type_change(struct net_device *dev, unsigned long event)
2650 {
2651 	struct inet6_dev *idev;
2652 	ASSERT_RTNL();
2653 
2654 	idev = __in6_dev_get(dev);
2655 
2656 	if (event == NETDEV_POST_TYPE_CHANGE)
2657 		ipv6_mc_remap(idev);
2658 	else if (event == NETDEV_PRE_TYPE_CHANGE)
2659 		ipv6_mc_unmap(idev);
2660 }
2661 
2662 static int addrconf_ifdown(struct net_device *dev, int how)
2663 {
2664 	struct net *net = dev_net(dev);
2665 	struct inet6_dev *idev;
2666 	struct inet6_ifaddr *ifa;
2667 	LIST_HEAD(keep_list);
2668 	int state;
2669 
2670 	ASSERT_RTNL();
2671 
2672 	/* Flush routes if device is being removed or it is not loopback */
2673 	if (how || !(dev->flags & IFF_LOOPBACK))
2674 		rt6_ifdown(net, dev);
2675 
2676 	idev = __in6_dev_get(dev);
2677 	if (idev == NULL)
2678 		return -ENODEV;
2679 
2680 	/*
2681 	 * Step 1: remove reference to ipv6 device from parent device.
2682 	 *	   Do not dev_put!
2683 	 */
2684 	if (how) {
2685 		idev->dead = 1;
2686 
2687 		/* protected by rtnl_lock */
2688 		rcu_assign_pointer(dev->ip6_ptr, NULL);
2689 
2690 		/* Step 1.5: remove snmp6 entry */
2691 		snmp6_unregister_dev(idev);
2692 
2693 	}
2694 
2695 	write_lock_bh(&idev->lock);
2696 
2697 	/* Step 2: clear flags for stateless addrconf */
2698 	if (!how)
2699 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
2700 
2701 #ifdef CONFIG_IPV6_PRIVACY
2702 	if (how && del_timer(&idev->regen_timer))
2703 		in6_dev_put(idev);
2704 
2705 	/* Step 3: clear tempaddr list */
2706 	while (!list_empty(&idev->tempaddr_list)) {
2707 		ifa = list_first_entry(&idev->tempaddr_list,
2708 				       struct inet6_ifaddr, tmp_list);
2709 		list_del(&ifa->tmp_list);
2710 		write_unlock_bh(&idev->lock);
2711 		spin_lock_bh(&ifa->lock);
2712 
2713 		if (ifa->ifpub) {
2714 			in6_ifa_put(ifa->ifpub);
2715 			ifa->ifpub = NULL;
2716 		}
2717 		spin_unlock_bh(&ifa->lock);
2718 		in6_ifa_put(ifa);
2719 		write_lock_bh(&idev->lock);
2720 	}
2721 #endif
2722 
2723 	while (!list_empty(&idev->addr_list)) {
2724 		ifa = list_first_entry(&idev->addr_list,
2725 				       struct inet6_ifaddr, if_list);
2726 		addrconf_del_timer(ifa);
2727 
2728 		/* If just doing link down, and address is permanent
2729 		   and not link-local, then retain it. */
2730 		if (!how &&
2731 		    (ifa->flags&IFA_F_PERMANENT) &&
2732 		    !(ipv6_addr_type(&ifa->addr) & IPV6_ADDR_LINKLOCAL)) {
2733 			list_move_tail(&ifa->if_list, &keep_list);
2734 
2735 			/* If not doing DAD on this address, just keep it. */
2736 			if ((dev->flags&(IFF_NOARP|IFF_LOOPBACK)) ||
2737 			    idev->cnf.accept_dad <= 0 ||
2738 			    (ifa->flags & IFA_F_NODAD))
2739 				continue;
2740 
2741 			/* If it was tentative already, no need to notify */
2742 			if (ifa->flags & IFA_F_TENTATIVE)
2743 				continue;
2744 
2745 			/* Flag it for later restoration when link comes up */
2746 			ifa->flags |= IFA_F_TENTATIVE;
2747 			ifa->state = INET6_IFADDR_STATE_DAD;
2748 		} else {
2749 			list_del(&ifa->if_list);
2750 
2751 			/* clear hash table */
2752 			spin_lock_bh(&addrconf_hash_lock);
2753 			hlist_del_init_rcu(&ifa->addr_lst);
2754 			spin_unlock_bh(&addrconf_hash_lock);
2755 
2756 			write_unlock_bh(&idev->lock);
2757 			spin_lock_bh(&ifa->state_lock);
2758 			state = ifa->state;
2759 			ifa->state = INET6_IFADDR_STATE_DEAD;
2760 			spin_unlock_bh(&ifa->state_lock);
2761 
2762 			if (state != INET6_IFADDR_STATE_DEAD) {
2763 				__ipv6_ifa_notify(RTM_DELADDR, ifa);
2764 				atomic_notifier_call_chain(&inet6addr_chain,
2765 							   NETDEV_DOWN, ifa);
2766 			}
2767 
2768 			in6_ifa_put(ifa);
2769 			write_lock_bh(&idev->lock);
2770 		}
2771 	}
2772 
2773 	list_splice(&keep_list, &idev->addr_list);
2774 
2775 	write_unlock_bh(&idev->lock);
2776 
2777 	/* Step 5: Discard multicast list */
2778 	if (how)
2779 		ipv6_mc_destroy_dev(idev);
2780 	else
2781 		ipv6_mc_down(idev);
2782 
2783 	idev->tstamp = jiffies;
2784 
2785 	/* Last: Shot the device (if unregistered) */
2786 	if (how) {
2787 		addrconf_sysctl_unregister(idev);
2788 		neigh_parms_release(&nd_tbl, idev->nd_parms);
2789 		neigh_ifdown(&nd_tbl, dev);
2790 		in6_dev_put(idev);
2791 	}
2792 	return 0;
2793 }
2794 
2795 static void addrconf_rs_timer(unsigned long data)
2796 {
2797 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
2798 	struct inet6_dev *idev = ifp->idev;
2799 
2800 	read_lock(&idev->lock);
2801 	if (idev->dead || !(idev->if_flags & IF_READY))
2802 		goto out;
2803 
2804 	if (idev->cnf.forwarding)
2805 		goto out;
2806 
2807 	/* Announcement received after solicitation was sent */
2808 	if (idev->if_flags & IF_RA_RCVD)
2809 		goto out;
2810 
2811 	spin_lock(&ifp->lock);
2812 	if (ifp->probes++ < idev->cnf.rtr_solicits) {
2813 		/* The wait after the last probe can be shorter */
2814 		addrconf_mod_timer(ifp, AC_RS,
2815 				   (ifp->probes == idev->cnf.rtr_solicits) ?
2816 				   idev->cnf.rtr_solicit_delay :
2817 				   idev->cnf.rtr_solicit_interval);
2818 		spin_unlock(&ifp->lock);
2819 
2820 		ndisc_send_rs(idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
2821 	} else {
2822 		spin_unlock(&ifp->lock);
2823 		/*
2824 		 * Note: we do not support deprecated "all on-link"
2825 		 * assumption any longer.
2826 		 */
2827 		printk(KERN_DEBUG "%s: no IPv6 routers present\n",
2828 		       idev->dev->name);
2829 	}
2830 
2831 out:
2832 	read_unlock(&idev->lock);
2833 	in6_ifa_put(ifp);
2834 }
2835 
2836 /*
2837  *	Duplicate Address Detection
2838  */
2839 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
2840 {
2841 	unsigned long rand_num;
2842 	struct inet6_dev *idev = ifp->idev;
2843 
2844 	if (ifp->flags & IFA_F_OPTIMISTIC)
2845 		rand_num = 0;
2846 	else
2847 		rand_num = net_random() % (idev->cnf.rtr_solicit_delay ? : 1);
2848 
2849 	ifp->probes = idev->cnf.dad_transmits;
2850 	addrconf_mod_timer(ifp, AC_DAD, rand_num);
2851 }
2852 
2853 static void addrconf_dad_start(struct inet6_ifaddr *ifp, u32 flags)
2854 {
2855 	struct inet6_dev *idev = ifp->idev;
2856 	struct net_device *dev = idev->dev;
2857 
2858 	addrconf_join_solict(dev, &ifp->addr);
2859 
2860 	net_srandom(ifp->addr.s6_addr32[3]);
2861 
2862 	read_lock_bh(&idev->lock);
2863 	spin_lock(&ifp->lock);
2864 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
2865 		goto out;
2866 
2867 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
2868 	    idev->cnf.accept_dad < 1 ||
2869 	    !(ifp->flags&IFA_F_TENTATIVE) ||
2870 	    ifp->flags & IFA_F_NODAD) {
2871 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
2872 		spin_unlock(&ifp->lock);
2873 		read_unlock_bh(&idev->lock);
2874 
2875 		addrconf_dad_completed(ifp);
2876 		return;
2877 	}
2878 
2879 	if (!(idev->if_flags & IF_READY)) {
2880 		spin_unlock(&ifp->lock);
2881 		read_unlock_bh(&idev->lock);
2882 		/*
2883 		 * If the device is not ready:
2884 		 * - keep it tentative if it is a permanent address.
2885 		 * - otherwise, kill it.
2886 		 */
2887 		in6_ifa_hold(ifp);
2888 		addrconf_dad_stop(ifp, 0);
2889 		return;
2890 	}
2891 
2892 	/*
2893 	 * Optimistic nodes can start receiving
2894 	 * Frames right away
2895 	 */
2896 	if (ifp->flags & IFA_F_OPTIMISTIC)
2897 		ip6_ins_rt(ifp->rt);
2898 
2899 	addrconf_dad_kick(ifp);
2900 out:
2901 	spin_unlock(&ifp->lock);
2902 	read_unlock_bh(&idev->lock);
2903 }
2904 
2905 static void addrconf_dad_timer(unsigned long data)
2906 {
2907 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
2908 	struct inet6_dev *idev = ifp->idev;
2909 	struct in6_addr mcaddr;
2910 
2911 	if (!ifp->probes && addrconf_dad_end(ifp))
2912 		goto out;
2913 
2914 	read_lock(&idev->lock);
2915 	if (idev->dead || !(idev->if_flags & IF_READY)) {
2916 		read_unlock(&idev->lock);
2917 		goto out;
2918 	}
2919 
2920 	spin_lock(&ifp->lock);
2921 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
2922 		spin_unlock(&ifp->lock);
2923 		read_unlock(&idev->lock);
2924 		goto out;
2925 	}
2926 
2927 	if (ifp->probes == 0) {
2928 		/*
2929 		 * DAD was successful
2930 		 */
2931 
2932 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
2933 		spin_unlock(&ifp->lock);
2934 		read_unlock(&idev->lock);
2935 
2936 		addrconf_dad_completed(ifp);
2937 
2938 		goto out;
2939 	}
2940 
2941 	ifp->probes--;
2942 	addrconf_mod_timer(ifp, AC_DAD, ifp->idev->nd_parms->retrans_time);
2943 	spin_unlock(&ifp->lock);
2944 	read_unlock(&idev->lock);
2945 
2946 	/* send a neighbour solicitation for our addr */
2947 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
2948 	ndisc_send_ns(ifp->idev->dev, NULL, &ifp->addr, &mcaddr, &in6addr_any);
2949 out:
2950 	in6_ifa_put(ifp);
2951 }
2952 
2953 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
2954 {
2955 	struct net_device *dev = ifp->idev->dev;
2956 
2957 	/*
2958 	 *	Configure the address for reception. Now it is valid.
2959 	 */
2960 
2961 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
2962 
2963 	/* If added prefix is link local and forwarding is off,
2964 	   start sending router solicitations.
2965 	 */
2966 
2967 	if ((ifp->idev->cnf.forwarding == 0 ||
2968 	     ifp->idev->cnf.forwarding == 2) &&
2969 	    ifp->idev->cnf.rtr_solicits > 0 &&
2970 	    (dev->flags&IFF_LOOPBACK) == 0 &&
2971 	    (ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL)) {
2972 		/*
2973 		 *	If a host as already performed a random delay
2974 		 *	[...] as part of DAD [...] there is no need
2975 		 *	to delay again before sending the first RS
2976 		 */
2977 		ndisc_send_rs(ifp->idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
2978 
2979 		spin_lock_bh(&ifp->lock);
2980 		ifp->probes = 1;
2981 		ifp->idev->if_flags |= IF_RS_SENT;
2982 		addrconf_mod_timer(ifp, AC_RS, ifp->idev->cnf.rtr_solicit_interval);
2983 		spin_unlock_bh(&ifp->lock);
2984 	}
2985 }
2986 
2987 static void addrconf_dad_run(struct inet6_dev *idev)
2988 {
2989 	struct inet6_ifaddr *ifp;
2990 
2991 	read_lock_bh(&idev->lock);
2992 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2993 		spin_lock(&ifp->lock);
2994 		if (ifp->flags & IFA_F_TENTATIVE &&
2995 		    ifp->state == INET6_IFADDR_STATE_DAD)
2996 			addrconf_dad_kick(ifp);
2997 		spin_unlock(&ifp->lock);
2998 	}
2999 	read_unlock_bh(&idev->lock);
3000 }
3001 
3002 #ifdef CONFIG_PROC_FS
3003 struct if6_iter_state {
3004 	struct seq_net_private p;
3005 	int bucket;
3006 };
3007 
3008 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq)
3009 {
3010 	struct inet6_ifaddr *ifa = NULL;
3011 	struct if6_iter_state *state = seq->private;
3012 	struct net *net = seq_file_net(seq);
3013 
3014 	for (state->bucket = 0; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
3015 		struct hlist_node *n;
3016 		hlist_for_each_entry_rcu_bh(ifa, n, &inet6_addr_lst[state->bucket],
3017 					 addr_lst)
3018 			if (net_eq(dev_net(ifa->idev->dev), net))
3019 				return ifa;
3020 	}
3021 	return NULL;
3022 }
3023 
3024 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
3025 					 struct inet6_ifaddr *ifa)
3026 {
3027 	struct if6_iter_state *state = seq->private;
3028 	struct net *net = seq_file_net(seq);
3029 	struct hlist_node *n = &ifa->addr_lst;
3030 
3031 	hlist_for_each_entry_continue_rcu_bh(ifa, n, addr_lst)
3032 		if (net_eq(dev_net(ifa->idev->dev), net))
3033 			return ifa;
3034 
3035 	while (++state->bucket < IN6_ADDR_HSIZE) {
3036 		hlist_for_each_entry_rcu_bh(ifa, n,
3037 				     &inet6_addr_lst[state->bucket], addr_lst) {
3038 			if (net_eq(dev_net(ifa->idev->dev), net))
3039 				return ifa;
3040 		}
3041 	}
3042 
3043 	return NULL;
3044 }
3045 
3046 static struct inet6_ifaddr *if6_get_idx(struct seq_file *seq, loff_t pos)
3047 {
3048 	struct inet6_ifaddr *ifa = if6_get_first(seq);
3049 
3050 	if (ifa)
3051 		while (pos && (ifa = if6_get_next(seq, ifa)) != NULL)
3052 			--pos;
3053 	return pos ? NULL : ifa;
3054 }
3055 
3056 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
3057 	__acquires(rcu_bh)
3058 {
3059 	rcu_read_lock_bh();
3060 	return if6_get_idx(seq, *pos);
3061 }
3062 
3063 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3064 {
3065 	struct inet6_ifaddr *ifa;
3066 
3067 	ifa = if6_get_next(seq, v);
3068 	++*pos;
3069 	return ifa;
3070 }
3071 
3072 static void if6_seq_stop(struct seq_file *seq, void *v)
3073 	__releases(rcu_bh)
3074 {
3075 	rcu_read_unlock_bh();
3076 }
3077 
3078 static int if6_seq_show(struct seq_file *seq, void *v)
3079 {
3080 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
3081 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
3082 		   &ifp->addr,
3083 		   ifp->idev->dev->ifindex,
3084 		   ifp->prefix_len,
3085 		   ifp->scope,
3086 		   ifp->flags,
3087 		   ifp->idev->dev->name);
3088 	return 0;
3089 }
3090 
3091 static const struct seq_operations if6_seq_ops = {
3092 	.start	= if6_seq_start,
3093 	.next	= if6_seq_next,
3094 	.show	= if6_seq_show,
3095 	.stop	= if6_seq_stop,
3096 };
3097 
3098 static int if6_seq_open(struct inode *inode, struct file *file)
3099 {
3100 	return seq_open_net(inode, file, &if6_seq_ops,
3101 			    sizeof(struct if6_iter_state));
3102 }
3103 
3104 static const struct file_operations if6_fops = {
3105 	.owner		= THIS_MODULE,
3106 	.open		= if6_seq_open,
3107 	.read		= seq_read,
3108 	.llseek		= seq_lseek,
3109 	.release	= seq_release_net,
3110 };
3111 
3112 static int __net_init if6_proc_net_init(struct net *net)
3113 {
3114 	if (!proc_net_fops_create(net, "if_inet6", S_IRUGO, &if6_fops))
3115 		return -ENOMEM;
3116 	return 0;
3117 }
3118 
3119 static void __net_exit if6_proc_net_exit(struct net *net)
3120 {
3121        proc_net_remove(net, "if_inet6");
3122 }
3123 
3124 static struct pernet_operations if6_proc_net_ops = {
3125        .init = if6_proc_net_init,
3126        .exit = if6_proc_net_exit,
3127 };
3128 
3129 int __init if6_proc_init(void)
3130 {
3131 	return register_pernet_subsys(&if6_proc_net_ops);
3132 }
3133 
3134 void if6_proc_exit(void)
3135 {
3136 	unregister_pernet_subsys(&if6_proc_net_ops);
3137 }
3138 #endif	/* CONFIG_PROC_FS */
3139 
3140 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
3141 /* Check if address is a home address configured on any interface. */
3142 int ipv6_chk_home_addr(struct net *net, struct in6_addr *addr)
3143 {
3144 	int ret = 0;
3145 	struct inet6_ifaddr *ifp = NULL;
3146 	struct hlist_node *n;
3147 	unsigned int hash = ipv6_addr_hash(addr);
3148 
3149 	rcu_read_lock_bh();
3150 	hlist_for_each_entry_rcu_bh(ifp, n, &inet6_addr_lst[hash], addr_lst) {
3151 		if (!net_eq(dev_net(ifp->idev->dev), net))
3152 			continue;
3153 		if (ipv6_addr_equal(&ifp->addr, addr) &&
3154 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
3155 			ret = 1;
3156 			break;
3157 		}
3158 	}
3159 	rcu_read_unlock_bh();
3160 	return ret;
3161 }
3162 #endif
3163 
3164 /*
3165  *	Periodic address status verification
3166  */
3167 
3168 static void addrconf_verify(unsigned long foo)
3169 {
3170 	unsigned long now, next, next_sec, next_sched;
3171 	struct inet6_ifaddr *ifp;
3172 	struct hlist_node *node;
3173 	int i;
3174 
3175 	rcu_read_lock_bh();
3176 	spin_lock(&addrconf_verify_lock);
3177 	now = jiffies;
3178 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
3179 
3180 	del_timer(&addr_chk_timer);
3181 
3182 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3183 restart:
3184 		hlist_for_each_entry_rcu_bh(ifp, node,
3185 					 &inet6_addr_lst[i], addr_lst) {
3186 			unsigned long age;
3187 
3188 			if (ifp->flags & IFA_F_PERMANENT)
3189 				continue;
3190 
3191 			spin_lock(&ifp->lock);
3192 			/* We try to batch several events at once. */
3193 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
3194 
3195 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
3196 			    age >= ifp->valid_lft) {
3197 				spin_unlock(&ifp->lock);
3198 				in6_ifa_hold(ifp);
3199 				ipv6_del_addr(ifp);
3200 				goto restart;
3201 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
3202 				spin_unlock(&ifp->lock);
3203 				continue;
3204 			} else if (age >= ifp->prefered_lft) {
3205 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
3206 				int deprecate = 0;
3207 
3208 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
3209 					deprecate = 1;
3210 					ifp->flags |= IFA_F_DEPRECATED;
3211 				}
3212 
3213 				if (time_before(ifp->tstamp + ifp->valid_lft * HZ, next))
3214 					next = ifp->tstamp + ifp->valid_lft * HZ;
3215 
3216 				spin_unlock(&ifp->lock);
3217 
3218 				if (deprecate) {
3219 					in6_ifa_hold(ifp);
3220 
3221 					ipv6_ifa_notify(0, ifp);
3222 					in6_ifa_put(ifp);
3223 					goto restart;
3224 				}
3225 #ifdef CONFIG_IPV6_PRIVACY
3226 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
3227 				   !(ifp->flags&IFA_F_TENTATIVE)) {
3228 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
3229 					ifp->idev->cnf.dad_transmits *
3230 					ifp->idev->nd_parms->retrans_time / HZ;
3231 
3232 				if (age >= ifp->prefered_lft - regen_advance) {
3233 					struct inet6_ifaddr *ifpub = ifp->ifpub;
3234 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3235 						next = ifp->tstamp + ifp->prefered_lft * HZ;
3236 					if (!ifp->regen_count && ifpub) {
3237 						ifp->regen_count++;
3238 						in6_ifa_hold(ifp);
3239 						in6_ifa_hold(ifpub);
3240 						spin_unlock(&ifp->lock);
3241 
3242 						spin_lock(&ifpub->lock);
3243 						ifpub->regen_count = 0;
3244 						spin_unlock(&ifpub->lock);
3245 						ipv6_create_tempaddr(ifpub, ifp);
3246 						in6_ifa_put(ifpub);
3247 						in6_ifa_put(ifp);
3248 						goto restart;
3249 					}
3250 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
3251 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
3252 				spin_unlock(&ifp->lock);
3253 #endif
3254 			} else {
3255 				/* ifp->prefered_lft <= ifp->valid_lft */
3256 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3257 					next = ifp->tstamp + ifp->prefered_lft * HZ;
3258 				spin_unlock(&ifp->lock);
3259 			}
3260 		}
3261 	}
3262 
3263 	next_sec = round_jiffies_up(next);
3264 	next_sched = next;
3265 
3266 	/* If rounded timeout is accurate enough, accept it. */
3267 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
3268 		next_sched = next_sec;
3269 
3270 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
3271 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
3272 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
3273 
3274 	ADBG((KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
3275 	      now, next, next_sec, next_sched));
3276 
3277 	addr_chk_timer.expires = next_sched;
3278 	add_timer(&addr_chk_timer);
3279 	spin_unlock(&addrconf_verify_lock);
3280 	rcu_read_unlock_bh();
3281 }
3282 
3283 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local)
3284 {
3285 	struct in6_addr *pfx = NULL;
3286 
3287 	if (addr)
3288 		pfx = nla_data(addr);
3289 
3290 	if (local) {
3291 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
3292 			pfx = NULL;
3293 		else
3294 			pfx = nla_data(local);
3295 	}
3296 
3297 	return pfx;
3298 }
3299 
3300 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
3301 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
3302 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
3303 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
3304 };
3305 
3306 static int
3307 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
3308 {
3309 	struct net *net = sock_net(skb->sk);
3310 	struct ifaddrmsg *ifm;
3311 	struct nlattr *tb[IFA_MAX+1];
3312 	struct in6_addr *pfx;
3313 	int err;
3314 
3315 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3316 	if (err < 0)
3317 		return err;
3318 
3319 	ifm = nlmsg_data(nlh);
3320 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3321 	if (pfx == NULL)
3322 		return -EINVAL;
3323 
3324 	return inet6_addr_del(net, ifm->ifa_index, pfx, ifm->ifa_prefixlen);
3325 }
3326 
3327 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u8 ifa_flags,
3328 			     u32 prefered_lft, u32 valid_lft)
3329 {
3330 	u32 flags;
3331 	clock_t expires;
3332 	unsigned long timeout;
3333 
3334 	if (!valid_lft || (prefered_lft > valid_lft))
3335 		return -EINVAL;
3336 
3337 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
3338 	if (addrconf_finite_timeout(timeout)) {
3339 		expires = jiffies_to_clock_t(timeout * HZ);
3340 		valid_lft = timeout;
3341 		flags = RTF_EXPIRES;
3342 	} else {
3343 		expires = 0;
3344 		flags = 0;
3345 		ifa_flags |= IFA_F_PERMANENT;
3346 	}
3347 
3348 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
3349 	if (addrconf_finite_timeout(timeout)) {
3350 		if (timeout == 0)
3351 			ifa_flags |= IFA_F_DEPRECATED;
3352 		prefered_lft = timeout;
3353 	}
3354 
3355 	spin_lock_bh(&ifp->lock);
3356 	ifp->flags = (ifp->flags & ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD | IFA_F_HOMEADDRESS)) | ifa_flags;
3357 	ifp->tstamp = jiffies;
3358 	ifp->valid_lft = valid_lft;
3359 	ifp->prefered_lft = prefered_lft;
3360 
3361 	spin_unlock_bh(&ifp->lock);
3362 	if (!(ifp->flags&IFA_F_TENTATIVE))
3363 		ipv6_ifa_notify(0, ifp);
3364 
3365 	addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
3366 			      expires, flags);
3367 	addrconf_verify(0);
3368 
3369 	return 0;
3370 }
3371 
3372 static int
3373 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
3374 {
3375 	struct net *net = sock_net(skb->sk);
3376 	struct ifaddrmsg *ifm;
3377 	struct nlattr *tb[IFA_MAX+1];
3378 	struct in6_addr *pfx;
3379 	struct inet6_ifaddr *ifa;
3380 	struct net_device *dev;
3381 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
3382 	u8 ifa_flags;
3383 	int err;
3384 
3385 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3386 	if (err < 0)
3387 		return err;
3388 
3389 	ifm = nlmsg_data(nlh);
3390 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3391 	if (pfx == NULL)
3392 		return -EINVAL;
3393 
3394 	if (tb[IFA_CACHEINFO]) {
3395 		struct ifa_cacheinfo *ci;
3396 
3397 		ci = nla_data(tb[IFA_CACHEINFO]);
3398 		valid_lft = ci->ifa_valid;
3399 		preferred_lft = ci->ifa_prefered;
3400 	} else {
3401 		preferred_lft = INFINITY_LIFE_TIME;
3402 		valid_lft = INFINITY_LIFE_TIME;
3403 	}
3404 
3405 	dev =  __dev_get_by_index(net, ifm->ifa_index);
3406 	if (dev == NULL)
3407 		return -ENODEV;
3408 
3409 	/* We ignore other flags so far. */
3410 	ifa_flags = ifm->ifa_flags & (IFA_F_NODAD | IFA_F_HOMEADDRESS);
3411 
3412 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
3413 	if (ifa == NULL) {
3414 		/*
3415 		 * It would be best to check for !NLM_F_CREATE here but
3416 		 * userspace alreay relies on not having to provide this.
3417 		 */
3418 		return inet6_addr_add(net, ifm->ifa_index, pfx,
3419 				      ifm->ifa_prefixlen, ifa_flags,
3420 				      preferred_lft, valid_lft);
3421 	}
3422 
3423 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
3424 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
3425 		err = -EEXIST;
3426 	else
3427 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
3428 
3429 	in6_ifa_put(ifa);
3430 
3431 	return err;
3432 }
3433 
3434 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u8 flags,
3435 			  u8 scope, int ifindex)
3436 {
3437 	struct ifaddrmsg *ifm;
3438 
3439 	ifm = nlmsg_data(nlh);
3440 	ifm->ifa_family = AF_INET6;
3441 	ifm->ifa_prefixlen = prefixlen;
3442 	ifm->ifa_flags = flags;
3443 	ifm->ifa_scope = scope;
3444 	ifm->ifa_index = ifindex;
3445 }
3446 
3447 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
3448 			 unsigned long tstamp, u32 preferred, u32 valid)
3449 {
3450 	struct ifa_cacheinfo ci;
3451 
3452 	ci.cstamp = cstamp_delta(cstamp);
3453 	ci.tstamp = cstamp_delta(tstamp);
3454 	ci.ifa_prefered = preferred;
3455 	ci.ifa_valid = valid;
3456 
3457 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
3458 }
3459 
3460 static inline int rt_scope(int ifa_scope)
3461 {
3462 	if (ifa_scope & IFA_HOST)
3463 		return RT_SCOPE_HOST;
3464 	else if (ifa_scope & IFA_LINK)
3465 		return RT_SCOPE_LINK;
3466 	else if (ifa_scope & IFA_SITE)
3467 		return RT_SCOPE_SITE;
3468 	else
3469 		return RT_SCOPE_UNIVERSE;
3470 }
3471 
3472 static inline int inet6_ifaddr_msgsize(void)
3473 {
3474 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
3475 	       + nla_total_size(16) /* IFA_ADDRESS */
3476 	       + nla_total_size(sizeof(struct ifa_cacheinfo));
3477 }
3478 
3479 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
3480 			     u32 pid, u32 seq, int event, unsigned int flags)
3481 {
3482 	struct nlmsghdr  *nlh;
3483 	u32 preferred, valid;
3484 
3485 	nlh = nlmsg_put(skb, pid, seq, event, sizeof(struct ifaddrmsg), flags);
3486 	if (nlh == NULL)
3487 		return -EMSGSIZE;
3488 
3489 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
3490 		      ifa->idev->dev->ifindex);
3491 
3492 	if (!(ifa->flags&IFA_F_PERMANENT)) {
3493 		preferred = ifa->prefered_lft;
3494 		valid = ifa->valid_lft;
3495 		if (preferred != INFINITY_LIFE_TIME) {
3496 			long tval = (jiffies - ifa->tstamp)/HZ;
3497 			if (preferred > tval)
3498 				preferred -= tval;
3499 			else
3500 				preferred = 0;
3501 			if (valid != INFINITY_LIFE_TIME) {
3502 				if (valid > tval)
3503 					valid -= tval;
3504 				else
3505 					valid = 0;
3506 			}
3507 		}
3508 	} else {
3509 		preferred = INFINITY_LIFE_TIME;
3510 		valid = INFINITY_LIFE_TIME;
3511 	}
3512 
3513 	if (nla_put(skb, IFA_ADDRESS, 16, &ifa->addr) < 0 ||
3514 	    put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0) {
3515 		nlmsg_cancel(skb, nlh);
3516 		return -EMSGSIZE;
3517 	}
3518 
3519 	return nlmsg_end(skb, nlh);
3520 }
3521 
3522 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
3523 				u32 pid, u32 seq, int event, u16 flags)
3524 {
3525 	struct nlmsghdr  *nlh;
3526 	u8 scope = RT_SCOPE_UNIVERSE;
3527 	int ifindex = ifmca->idev->dev->ifindex;
3528 
3529 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
3530 		scope = RT_SCOPE_SITE;
3531 
3532 	nlh = nlmsg_put(skb, pid, seq, event, sizeof(struct ifaddrmsg), flags);
3533 	if (nlh == NULL)
3534 		return -EMSGSIZE;
3535 
3536 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3537 	if (nla_put(skb, IFA_MULTICAST, 16, &ifmca->mca_addr) < 0 ||
3538 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
3539 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3540 		nlmsg_cancel(skb, nlh);
3541 		return -EMSGSIZE;
3542 	}
3543 
3544 	return nlmsg_end(skb, nlh);
3545 }
3546 
3547 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
3548 				u32 pid, u32 seq, int event, unsigned int flags)
3549 {
3550 	struct nlmsghdr  *nlh;
3551 	u8 scope = RT_SCOPE_UNIVERSE;
3552 	int ifindex = ifaca->aca_idev->dev->ifindex;
3553 
3554 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
3555 		scope = RT_SCOPE_SITE;
3556 
3557 	nlh = nlmsg_put(skb, pid, seq, event, sizeof(struct ifaddrmsg), flags);
3558 	if (nlh == NULL)
3559 		return -EMSGSIZE;
3560 
3561 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3562 	if (nla_put(skb, IFA_ANYCAST, 16, &ifaca->aca_addr) < 0 ||
3563 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
3564 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3565 		nlmsg_cancel(skb, nlh);
3566 		return -EMSGSIZE;
3567 	}
3568 
3569 	return nlmsg_end(skb, nlh);
3570 }
3571 
3572 enum addr_type_t {
3573 	UNICAST_ADDR,
3574 	MULTICAST_ADDR,
3575 	ANYCAST_ADDR,
3576 };
3577 
3578 /* called with rcu_read_lock() */
3579 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
3580 			  struct netlink_callback *cb, enum addr_type_t type,
3581 			  int s_ip_idx, int *p_ip_idx)
3582 {
3583 	struct ifmcaddr6 *ifmca;
3584 	struct ifacaddr6 *ifaca;
3585 	int err = 1;
3586 	int ip_idx = *p_ip_idx;
3587 
3588 	read_lock_bh(&idev->lock);
3589 	switch (type) {
3590 	case UNICAST_ADDR: {
3591 		struct inet6_ifaddr *ifa;
3592 
3593 		/* unicast address incl. temp addr */
3594 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
3595 			if (++ip_idx < s_ip_idx)
3596 				continue;
3597 			err = inet6_fill_ifaddr(skb, ifa,
3598 						NETLINK_CB(cb->skb).pid,
3599 						cb->nlh->nlmsg_seq,
3600 						RTM_NEWADDR,
3601 						NLM_F_MULTI);
3602 			if (err <= 0)
3603 				break;
3604 		}
3605 		break;
3606 	}
3607 	case MULTICAST_ADDR:
3608 		/* multicast address */
3609 		for (ifmca = idev->mc_list; ifmca;
3610 		     ifmca = ifmca->next, ip_idx++) {
3611 			if (ip_idx < s_ip_idx)
3612 				continue;
3613 			err = inet6_fill_ifmcaddr(skb, ifmca,
3614 						  NETLINK_CB(cb->skb).pid,
3615 						  cb->nlh->nlmsg_seq,
3616 						  RTM_GETMULTICAST,
3617 						  NLM_F_MULTI);
3618 			if (err <= 0)
3619 				break;
3620 		}
3621 		break;
3622 	case ANYCAST_ADDR:
3623 		/* anycast address */
3624 		for (ifaca = idev->ac_list; ifaca;
3625 		     ifaca = ifaca->aca_next, ip_idx++) {
3626 			if (ip_idx < s_ip_idx)
3627 				continue;
3628 			err = inet6_fill_ifacaddr(skb, ifaca,
3629 						  NETLINK_CB(cb->skb).pid,
3630 						  cb->nlh->nlmsg_seq,
3631 						  RTM_GETANYCAST,
3632 						  NLM_F_MULTI);
3633 			if (err <= 0)
3634 				break;
3635 		}
3636 		break;
3637 	default:
3638 		break;
3639 	}
3640 	read_unlock_bh(&idev->lock);
3641 	*p_ip_idx = ip_idx;
3642 	return err;
3643 }
3644 
3645 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
3646 			   enum addr_type_t type)
3647 {
3648 	struct net *net = sock_net(skb->sk);
3649 	int h, s_h;
3650 	int idx, ip_idx;
3651 	int s_idx, s_ip_idx;
3652 	struct net_device *dev;
3653 	struct inet6_dev *idev;
3654 	struct hlist_head *head;
3655 	struct hlist_node *node;
3656 
3657 	s_h = cb->args[0];
3658 	s_idx = idx = cb->args[1];
3659 	s_ip_idx = ip_idx = cb->args[2];
3660 
3661 	rcu_read_lock();
3662 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
3663 		idx = 0;
3664 		head = &net->dev_index_head[h];
3665 		hlist_for_each_entry_rcu(dev, node, head, index_hlist) {
3666 			if (idx < s_idx)
3667 				goto cont;
3668 			if (h > s_h || idx > s_idx)
3669 				s_ip_idx = 0;
3670 			ip_idx = 0;
3671 			idev = __in6_dev_get(dev);
3672 			if (!idev)
3673 				goto cont;
3674 
3675 			if (in6_dump_addrs(idev, skb, cb, type,
3676 					   s_ip_idx, &ip_idx) <= 0)
3677 				goto done;
3678 cont:
3679 			idx++;
3680 		}
3681 	}
3682 done:
3683 	rcu_read_unlock();
3684 	cb->args[0] = h;
3685 	cb->args[1] = idx;
3686 	cb->args[2] = ip_idx;
3687 
3688 	return skb->len;
3689 }
3690 
3691 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
3692 {
3693 	enum addr_type_t type = UNICAST_ADDR;
3694 
3695 	return inet6_dump_addr(skb, cb, type);
3696 }
3697 
3698 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
3699 {
3700 	enum addr_type_t type = MULTICAST_ADDR;
3701 
3702 	return inet6_dump_addr(skb, cb, type);
3703 }
3704 
3705 
3706 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
3707 {
3708 	enum addr_type_t type = ANYCAST_ADDR;
3709 
3710 	return inet6_dump_addr(skb, cb, type);
3711 }
3712 
3713 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr* nlh,
3714 			     void *arg)
3715 {
3716 	struct net *net = sock_net(in_skb->sk);
3717 	struct ifaddrmsg *ifm;
3718 	struct nlattr *tb[IFA_MAX+1];
3719 	struct in6_addr *addr = NULL;
3720 	struct net_device *dev = NULL;
3721 	struct inet6_ifaddr *ifa;
3722 	struct sk_buff *skb;
3723 	int err;
3724 
3725 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3726 	if (err < 0)
3727 		goto errout;
3728 
3729 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3730 	if (addr == NULL) {
3731 		err = -EINVAL;
3732 		goto errout;
3733 	}
3734 
3735 	ifm = nlmsg_data(nlh);
3736 	if (ifm->ifa_index)
3737 		dev = __dev_get_by_index(net, ifm->ifa_index);
3738 
3739 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
3740 	if (!ifa) {
3741 		err = -EADDRNOTAVAIL;
3742 		goto errout;
3743 	}
3744 
3745 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
3746 	if (!skb) {
3747 		err = -ENOBUFS;
3748 		goto errout_ifa;
3749 	}
3750 
3751 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).pid,
3752 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
3753 	if (err < 0) {
3754 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
3755 		WARN_ON(err == -EMSGSIZE);
3756 		kfree_skb(skb);
3757 		goto errout_ifa;
3758 	}
3759 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
3760 errout_ifa:
3761 	in6_ifa_put(ifa);
3762 errout:
3763 	return err;
3764 }
3765 
3766 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
3767 {
3768 	struct sk_buff *skb;
3769 	struct net *net = dev_net(ifa->idev->dev);
3770 	int err = -ENOBUFS;
3771 
3772 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
3773 	if (skb == NULL)
3774 		goto errout;
3775 
3776 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
3777 	if (err < 0) {
3778 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
3779 		WARN_ON(err == -EMSGSIZE);
3780 		kfree_skb(skb);
3781 		goto errout;
3782 	}
3783 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
3784 	return;
3785 errout:
3786 	if (err < 0)
3787 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
3788 }
3789 
3790 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
3791 				__s32 *array, int bytes)
3792 {
3793 	BUG_ON(bytes < (DEVCONF_MAX * 4));
3794 
3795 	memset(array, 0, bytes);
3796 	array[DEVCONF_FORWARDING] = cnf->forwarding;
3797 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
3798 	array[DEVCONF_MTU6] = cnf->mtu6;
3799 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
3800 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
3801 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
3802 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
3803 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
3804 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
3805 		jiffies_to_msecs(cnf->rtr_solicit_interval);
3806 	array[DEVCONF_RTR_SOLICIT_DELAY] =
3807 		jiffies_to_msecs(cnf->rtr_solicit_delay);
3808 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
3809 #ifdef CONFIG_IPV6_PRIVACY
3810 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
3811 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
3812 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
3813 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
3814 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
3815 #endif
3816 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
3817 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
3818 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
3819 #ifdef CONFIG_IPV6_ROUTER_PREF
3820 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
3821 	array[DEVCONF_RTR_PROBE_INTERVAL] =
3822 		jiffies_to_msecs(cnf->rtr_probe_interval);
3823 #ifdef CONFIG_IPV6_ROUTE_INFO
3824 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
3825 #endif
3826 #endif
3827 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
3828 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
3829 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3830 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
3831 #endif
3832 #ifdef CONFIG_IPV6_MROUTE
3833 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
3834 #endif
3835 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
3836 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
3837 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
3838 }
3839 
3840 static inline size_t inet6_ifla6_size(void)
3841 {
3842 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
3843 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
3844 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
3845 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
3846 	     + nla_total_size(ICMP6_MIB_MAX * 8); /* IFLA_INET6_ICMP6STATS */
3847 }
3848 
3849 static inline size_t inet6_if_nlmsg_size(void)
3850 {
3851 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
3852 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
3853 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
3854 	       + nla_total_size(4) /* IFLA_MTU */
3855 	       + nla_total_size(4) /* IFLA_LINK */
3856 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
3857 }
3858 
3859 static inline void __snmp6_fill_stats(u64 *stats, void __percpu **mib,
3860 				      int items, int bytes)
3861 {
3862 	int i;
3863 	int pad = bytes - sizeof(u64) * items;
3864 	BUG_ON(pad < 0);
3865 
3866 	/* Use put_unaligned() because stats may not be aligned for u64. */
3867 	put_unaligned(items, &stats[0]);
3868 	for (i = 1; i < items; i++)
3869 		put_unaligned(snmp_fold_field(mib, i), &stats[i]);
3870 
3871 	memset(&stats[items], 0, pad);
3872 }
3873 
3874 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu **mib,
3875 				      int items, int bytes, size_t syncpoff)
3876 {
3877 	int i;
3878 	int pad = bytes - sizeof(u64) * items;
3879 	BUG_ON(pad < 0);
3880 
3881 	/* Use put_unaligned() because stats may not be aligned for u64. */
3882 	put_unaligned(items, &stats[0]);
3883 	for (i = 1; i < items; i++)
3884 		put_unaligned(snmp_fold_field64(mib, i, syncpoff), &stats[i]);
3885 
3886 	memset(&stats[items], 0, pad);
3887 }
3888 
3889 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
3890 			     int bytes)
3891 {
3892 	switch (attrtype) {
3893 	case IFLA_INET6_STATS:
3894 		__snmp6_fill_stats64(stats, (void __percpu **)idev->stats.ipv6,
3895 				     IPSTATS_MIB_MAX, bytes, offsetof(struct ipstats_mib, syncp));
3896 		break;
3897 	case IFLA_INET6_ICMP6STATS:
3898 		__snmp6_fill_stats(stats, (void __percpu **)idev->stats.icmpv6, ICMP6_MIB_MAX, bytes);
3899 		break;
3900 	}
3901 }
3902 
3903 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev)
3904 {
3905 	struct nlattr *nla;
3906 	struct ifla_cacheinfo ci;
3907 
3908 	NLA_PUT_U32(skb, IFLA_INET6_FLAGS, idev->if_flags);
3909 
3910 	ci.max_reasm_len = IPV6_MAXPLEN;
3911 	ci.tstamp = cstamp_delta(idev->tstamp);
3912 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
3913 	ci.retrans_time = jiffies_to_msecs(idev->nd_parms->retrans_time);
3914 	NLA_PUT(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci);
3915 
3916 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
3917 	if (nla == NULL)
3918 		goto nla_put_failure;
3919 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
3920 
3921 	/* XXX - MC not implemented */
3922 
3923 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
3924 	if (nla == NULL)
3925 		goto nla_put_failure;
3926 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
3927 
3928 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
3929 	if (nla == NULL)
3930 		goto nla_put_failure;
3931 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
3932 
3933 	return 0;
3934 
3935 nla_put_failure:
3936 	return -EMSGSIZE;
3937 }
3938 
3939 static size_t inet6_get_link_af_size(const struct net_device *dev)
3940 {
3941 	if (!__in6_dev_get(dev))
3942 		return 0;
3943 
3944 	return inet6_ifla6_size();
3945 }
3946 
3947 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
3948 {
3949 	struct inet6_dev *idev = __in6_dev_get(dev);
3950 
3951 	if (!idev)
3952 		return -ENODATA;
3953 
3954 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
3955 		return -EMSGSIZE;
3956 
3957 	return 0;
3958 }
3959 
3960 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
3961 			     u32 pid, u32 seq, int event, unsigned int flags)
3962 {
3963 	struct net_device *dev = idev->dev;
3964 	struct ifinfomsg *hdr;
3965 	struct nlmsghdr *nlh;
3966 	void *protoinfo;
3967 
3968 	nlh = nlmsg_put(skb, pid, seq, event, sizeof(*hdr), flags);
3969 	if (nlh == NULL)
3970 		return -EMSGSIZE;
3971 
3972 	hdr = nlmsg_data(nlh);
3973 	hdr->ifi_family = AF_INET6;
3974 	hdr->__ifi_pad = 0;
3975 	hdr->ifi_type = dev->type;
3976 	hdr->ifi_index = dev->ifindex;
3977 	hdr->ifi_flags = dev_get_flags(dev);
3978 	hdr->ifi_change = 0;
3979 
3980 	NLA_PUT_STRING(skb, IFLA_IFNAME, dev->name);
3981 
3982 	if (dev->addr_len)
3983 		NLA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr);
3984 
3985 	NLA_PUT_U32(skb, IFLA_MTU, dev->mtu);
3986 	if (dev->ifindex != dev->iflink)
3987 		NLA_PUT_U32(skb, IFLA_LINK, dev->iflink);
3988 
3989 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
3990 	if (protoinfo == NULL)
3991 		goto nla_put_failure;
3992 
3993 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
3994 		goto nla_put_failure;
3995 
3996 	nla_nest_end(skb, protoinfo);
3997 	return nlmsg_end(skb, nlh);
3998 
3999 nla_put_failure:
4000 	nlmsg_cancel(skb, nlh);
4001 	return -EMSGSIZE;
4002 }
4003 
4004 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
4005 {
4006 	struct net *net = sock_net(skb->sk);
4007 	int h, s_h;
4008 	int idx = 0, s_idx;
4009 	struct net_device *dev;
4010 	struct inet6_dev *idev;
4011 	struct hlist_head *head;
4012 	struct hlist_node *node;
4013 
4014 	s_h = cb->args[0];
4015 	s_idx = cb->args[1];
4016 
4017 	rcu_read_lock();
4018 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4019 		idx = 0;
4020 		head = &net->dev_index_head[h];
4021 		hlist_for_each_entry_rcu(dev, node, head, index_hlist) {
4022 			if (idx < s_idx)
4023 				goto cont;
4024 			idev = __in6_dev_get(dev);
4025 			if (!idev)
4026 				goto cont;
4027 			if (inet6_fill_ifinfo(skb, idev,
4028 					      NETLINK_CB(cb->skb).pid,
4029 					      cb->nlh->nlmsg_seq,
4030 					      RTM_NEWLINK, NLM_F_MULTI) <= 0)
4031 				goto out;
4032 cont:
4033 			idx++;
4034 		}
4035 	}
4036 out:
4037 	rcu_read_unlock();
4038 	cb->args[1] = idx;
4039 	cb->args[0] = h;
4040 
4041 	return skb->len;
4042 }
4043 
4044 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
4045 {
4046 	struct sk_buff *skb;
4047 	struct net *net = dev_net(idev->dev);
4048 	int err = -ENOBUFS;
4049 
4050 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
4051 	if (skb == NULL)
4052 		goto errout;
4053 
4054 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
4055 	if (err < 0) {
4056 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
4057 		WARN_ON(err == -EMSGSIZE);
4058 		kfree_skb(skb);
4059 		goto errout;
4060 	}
4061 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
4062 	return;
4063 errout:
4064 	if (err < 0)
4065 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
4066 }
4067 
4068 static inline size_t inet6_prefix_nlmsg_size(void)
4069 {
4070 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
4071 	       + nla_total_size(sizeof(struct in6_addr))
4072 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
4073 }
4074 
4075 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
4076 			     struct prefix_info *pinfo, u32 pid, u32 seq,
4077 			     int event, unsigned int flags)
4078 {
4079 	struct prefixmsg *pmsg;
4080 	struct nlmsghdr *nlh;
4081 	struct prefix_cacheinfo	ci;
4082 
4083 	nlh = nlmsg_put(skb, pid, seq, event, sizeof(*pmsg), flags);
4084 	if (nlh == NULL)
4085 		return -EMSGSIZE;
4086 
4087 	pmsg = nlmsg_data(nlh);
4088 	pmsg->prefix_family = AF_INET6;
4089 	pmsg->prefix_pad1 = 0;
4090 	pmsg->prefix_pad2 = 0;
4091 	pmsg->prefix_ifindex = idev->dev->ifindex;
4092 	pmsg->prefix_len = pinfo->prefix_len;
4093 	pmsg->prefix_type = pinfo->type;
4094 	pmsg->prefix_pad3 = 0;
4095 	pmsg->prefix_flags = 0;
4096 	if (pinfo->onlink)
4097 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
4098 	if (pinfo->autoconf)
4099 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
4100 
4101 	NLA_PUT(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix);
4102 
4103 	ci.preferred_time = ntohl(pinfo->prefered);
4104 	ci.valid_time = ntohl(pinfo->valid);
4105 	NLA_PUT(skb, PREFIX_CACHEINFO, sizeof(ci), &ci);
4106 
4107 	return nlmsg_end(skb, nlh);
4108 
4109 nla_put_failure:
4110 	nlmsg_cancel(skb, nlh);
4111 	return -EMSGSIZE;
4112 }
4113 
4114 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
4115 			 struct prefix_info *pinfo)
4116 {
4117 	struct sk_buff *skb;
4118 	struct net *net = dev_net(idev->dev);
4119 	int err = -ENOBUFS;
4120 
4121 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
4122 	if (skb == NULL)
4123 		goto errout;
4124 
4125 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
4126 	if (err < 0) {
4127 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
4128 		WARN_ON(err == -EMSGSIZE);
4129 		kfree_skb(skb);
4130 		goto errout;
4131 	}
4132 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
4133 	return;
4134 errout:
4135 	if (err < 0)
4136 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
4137 }
4138 
4139 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4140 {
4141 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
4142 
4143 	switch (event) {
4144 	case RTM_NEWADDR:
4145 		/*
4146 		 * If the address was optimistic
4147 		 * we inserted the route at the start of
4148 		 * our DAD process, so we don't need
4149 		 * to do it again
4150 		 */
4151 		if (!(ifp->rt->rt6i_node))
4152 			ip6_ins_rt(ifp->rt);
4153 		if (ifp->idev->cnf.forwarding)
4154 			addrconf_join_anycast(ifp);
4155 		break;
4156 	case RTM_DELADDR:
4157 		if (ifp->idev->cnf.forwarding)
4158 			addrconf_leave_anycast(ifp);
4159 		addrconf_leave_solict(ifp->idev, &ifp->addr);
4160 		dst_hold(&ifp->rt->dst);
4161 
4162 		if (ifp->state == INET6_IFADDR_STATE_DEAD &&
4163 		    ip6_del_rt(ifp->rt))
4164 			dst_free(&ifp->rt->dst);
4165 		break;
4166 	}
4167 }
4168 
4169 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4170 {
4171 	rcu_read_lock_bh();
4172 	if (likely(ifp->idev->dead == 0))
4173 		__ipv6_ifa_notify(event, ifp);
4174 	rcu_read_unlock_bh();
4175 }
4176 
4177 #ifdef CONFIG_SYSCTL
4178 
4179 static
4180 int addrconf_sysctl_forward(ctl_table *ctl, int write,
4181 			   void __user *buffer, size_t *lenp, loff_t *ppos)
4182 {
4183 	int *valp = ctl->data;
4184 	int val = *valp;
4185 	loff_t pos = *ppos;
4186 	int ret;
4187 
4188 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
4189 
4190 	if (write)
4191 		ret = addrconf_fixup_forwarding(ctl, valp, val);
4192 	if (ret)
4193 		*ppos = pos;
4194 	return ret;
4195 }
4196 
4197 static void dev_disable_change(struct inet6_dev *idev)
4198 {
4199 	if (!idev || !idev->dev)
4200 		return;
4201 
4202 	if (idev->cnf.disable_ipv6)
4203 		addrconf_notify(NULL, NETDEV_DOWN, idev->dev);
4204 	else
4205 		addrconf_notify(NULL, NETDEV_UP, idev->dev);
4206 }
4207 
4208 static void addrconf_disable_change(struct net *net, __s32 newf)
4209 {
4210 	struct net_device *dev;
4211 	struct inet6_dev *idev;
4212 
4213 	rcu_read_lock();
4214 	for_each_netdev_rcu(net, dev) {
4215 		idev = __in6_dev_get(dev);
4216 		if (idev) {
4217 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
4218 			idev->cnf.disable_ipv6 = newf;
4219 			if (changed)
4220 				dev_disable_change(idev);
4221 		}
4222 	}
4223 	rcu_read_unlock();
4224 }
4225 
4226 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int old)
4227 {
4228 	struct net *net;
4229 
4230 	net = (struct net *)table->extra2;
4231 
4232 	if (p == &net->ipv6.devconf_dflt->disable_ipv6)
4233 		return 0;
4234 
4235 	if (!rtnl_trylock()) {
4236 		/* Restore the original values before restarting */
4237 		*p = old;
4238 		return restart_syscall();
4239 	}
4240 
4241 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
4242 		__s32 newf = net->ipv6.devconf_all->disable_ipv6;
4243 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
4244 		addrconf_disable_change(net, newf);
4245 	} else if ((!*p) ^ (!old))
4246 		dev_disable_change((struct inet6_dev *)table->extra1);
4247 
4248 	rtnl_unlock();
4249 	return 0;
4250 }
4251 
4252 static
4253 int addrconf_sysctl_disable(ctl_table *ctl, int write,
4254 			    void __user *buffer, size_t *lenp, loff_t *ppos)
4255 {
4256 	int *valp = ctl->data;
4257 	int val = *valp;
4258 	loff_t pos = *ppos;
4259 	int ret;
4260 
4261 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
4262 
4263 	if (write)
4264 		ret = addrconf_disable_ipv6(ctl, valp, val);
4265 	if (ret)
4266 		*ppos = pos;
4267 	return ret;
4268 }
4269 
4270 static struct addrconf_sysctl_table
4271 {
4272 	struct ctl_table_header *sysctl_header;
4273 	ctl_table addrconf_vars[DEVCONF_MAX+1];
4274 	char *dev_name;
4275 } addrconf_sysctl __read_mostly = {
4276 	.sysctl_header = NULL,
4277 	.addrconf_vars = {
4278 		{
4279 			.procname	= "forwarding",
4280 			.data		= &ipv6_devconf.forwarding,
4281 			.maxlen		= sizeof(int),
4282 			.mode		= 0644,
4283 			.proc_handler	= addrconf_sysctl_forward,
4284 		},
4285 		{
4286 			.procname	= "hop_limit",
4287 			.data		= &ipv6_devconf.hop_limit,
4288 			.maxlen		= sizeof(int),
4289 			.mode		= 0644,
4290 			.proc_handler	= proc_dointvec,
4291 		},
4292 		{
4293 			.procname	= "mtu",
4294 			.data		= &ipv6_devconf.mtu6,
4295 			.maxlen		= sizeof(int),
4296 			.mode		= 0644,
4297 			.proc_handler	= proc_dointvec,
4298 		},
4299 		{
4300 			.procname	= "accept_ra",
4301 			.data		= &ipv6_devconf.accept_ra,
4302 			.maxlen		= sizeof(int),
4303 			.mode		= 0644,
4304 			.proc_handler	= proc_dointvec,
4305 		},
4306 		{
4307 			.procname	= "accept_redirects",
4308 			.data		= &ipv6_devconf.accept_redirects,
4309 			.maxlen		= sizeof(int),
4310 			.mode		= 0644,
4311 			.proc_handler	= proc_dointvec,
4312 		},
4313 		{
4314 			.procname	= "autoconf",
4315 			.data		= &ipv6_devconf.autoconf,
4316 			.maxlen		= sizeof(int),
4317 			.mode		= 0644,
4318 			.proc_handler	= proc_dointvec,
4319 		},
4320 		{
4321 			.procname	= "dad_transmits",
4322 			.data		= &ipv6_devconf.dad_transmits,
4323 			.maxlen		= sizeof(int),
4324 			.mode		= 0644,
4325 			.proc_handler	= proc_dointvec,
4326 		},
4327 		{
4328 			.procname	= "router_solicitations",
4329 			.data		= &ipv6_devconf.rtr_solicits,
4330 			.maxlen		= sizeof(int),
4331 			.mode		= 0644,
4332 			.proc_handler	= proc_dointvec,
4333 		},
4334 		{
4335 			.procname	= "router_solicitation_interval",
4336 			.data		= &ipv6_devconf.rtr_solicit_interval,
4337 			.maxlen		= sizeof(int),
4338 			.mode		= 0644,
4339 			.proc_handler	= proc_dointvec_jiffies,
4340 		},
4341 		{
4342 			.procname	= "router_solicitation_delay",
4343 			.data		= &ipv6_devconf.rtr_solicit_delay,
4344 			.maxlen		= sizeof(int),
4345 			.mode		= 0644,
4346 			.proc_handler	= proc_dointvec_jiffies,
4347 		},
4348 		{
4349 			.procname	= "force_mld_version",
4350 			.data		= &ipv6_devconf.force_mld_version,
4351 			.maxlen		= sizeof(int),
4352 			.mode		= 0644,
4353 			.proc_handler	= proc_dointvec,
4354 		},
4355 #ifdef CONFIG_IPV6_PRIVACY
4356 		{
4357 			.procname	= "use_tempaddr",
4358 			.data		= &ipv6_devconf.use_tempaddr,
4359 			.maxlen		= sizeof(int),
4360 			.mode		= 0644,
4361 			.proc_handler	= proc_dointvec,
4362 		},
4363 		{
4364 			.procname	= "temp_valid_lft",
4365 			.data		= &ipv6_devconf.temp_valid_lft,
4366 			.maxlen		= sizeof(int),
4367 			.mode		= 0644,
4368 			.proc_handler	= proc_dointvec,
4369 		},
4370 		{
4371 			.procname	= "temp_prefered_lft",
4372 			.data		= &ipv6_devconf.temp_prefered_lft,
4373 			.maxlen		= sizeof(int),
4374 			.mode		= 0644,
4375 			.proc_handler	= proc_dointvec,
4376 		},
4377 		{
4378 			.procname	= "regen_max_retry",
4379 			.data		= &ipv6_devconf.regen_max_retry,
4380 			.maxlen		= sizeof(int),
4381 			.mode		= 0644,
4382 			.proc_handler	= proc_dointvec,
4383 		},
4384 		{
4385 			.procname	= "max_desync_factor",
4386 			.data		= &ipv6_devconf.max_desync_factor,
4387 			.maxlen		= sizeof(int),
4388 			.mode		= 0644,
4389 			.proc_handler	= proc_dointvec,
4390 		},
4391 #endif
4392 		{
4393 			.procname	= "max_addresses",
4394 			.data		= &ipv6_devconf.max_addresses,
4395 			.maxlen		= sizeof(int),
4396 			.mode		= 0644,
4397 			.proc_handler	= proc_dointvec,
4398 		},
4399 		{
4400 			.procname	= "accept_ra_defrtr",
4401 			.data		= &ipv6_devconf.accept_ra_defrtr,
4402 			.maxlen		= sizeof(int),
4403 			.mode		= 0644,
4404 			.proc_handler	= proc_dointvec,
4405 		},
4406 		{
4407 			.procname	= "accept_ra_pinfo",
4408 			.data		= &ipv6_devconf.accept_ra_pinfo,
4409 			.maxlen		= sizeof(int),
4410 			.mode		= 0644,
4411 			.proc_handler	= proc_dointvec,
4412 		},
4413 #ifdef CONFIG_IPV6_ROUTER_PREF
4414 		{
4415 			.procname	= "accept_ra_rtr_pref",
4416 			.data		= &ipv6_devconf.accept_ra_rtr_pref,
4417 			.maxlen		= sizeof(int),
4418 			.mode		= 0644,
4419 			.proc_handler	= proc_dointvec,
4420 		},
4421 		{
4422 			.procname	= "router_probe_interval",
4423 			.data		= &ipv6_devconf.rtr_probe_interval,
4424 			.maxlen		= sizeof(int),
4425 			.mode		= 0644,
4426 			.proc_handler	= proc_dointvec_jiffies,
4427 		},
4428 #ifdef CONFIG_IPV6_ROUTE_INFO
4429 		{
4430 			.procname	= "accept_ra_rt_info_max_plen",
4431 			.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
4432 			.maxlen		= sizeof(int),
4433 			.mode		= 0644,
4434 			.proc_handler	= proc_dointvec,
4435 		},
4436 #endif
4437 #endif
4438 		{
4439 			.procname	= "proxy_ndp",
4440 			.data		= &ipv6_devconf.proxy_ndp,
4441 			.maxlen		= sizeof(int),
4442 			.mode		= 0644,
4443 			.proc_handler	= proc_dointvec,
4444 		},
4445 		{
4446 			.procname	= "accept_source_route",
4447 			.data		= &ipv6_devconf.accept_source_route,
4448 			.maxlen		= sizeof(int),
4449 			.mode		= 0644,
4450 			.proc_handler	= proc_dointvec,
4451 		},
4452 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4453 		{
4454 			.procname       = "optimistic_dad",
4455 			.data           = &ipv6_devconf.optimistic_dad,
4456 			.maxlen         = sizeof(int),
4457 			.mode           = 0644,
4458 			.proc_handler   = proc_dointvec,
4459 
4460 		},
4461 #endif
4462 #ifdef CONFIG_IPV6_MROUTE
4463 		{
4464 			.procname	= "mc_forwarding",
4465 			.data		= &ipv6_devconf.mc_forwarding,
4466 			.maxlen		= sizeof(int),
4467 			.mode		= 0444,
4468 			.proc_handler	= proc_dointvec,
4469 		},
4470 #endif
4471 		{
4472 			.procname	= "disable_ipv6",
4473 			.data		= &ipv6_devconf.disable_ipv6,
4474 			.maxlen		= sizeof(int),
4475 			.mode		= 0644,
4476 			.proc_handler	= addrconf_sysctl_disable,
4477 		},
4478 		{
4479 			.procname	= "accept_dad",
4480 			.data		= &ipv6_devconf.accept_dad,
4481 			.maxlen		= sizeof(int),
4482 			.mode		= 0644,
4483 			.proc_handler	= proc_dointvec,
4484 		},
4485 		{
4486 			.procname       = "force_tllao",
4487 			.data           = &ipv6_devconf.force_tllao,
4488 			.maxlen         = sizeof(int),
4489 			.mode           = 0644,
4490 			.proc_handler   = proc_dointvec
4491 		},
4492 		{
4493 			/* sentinel */
4494 		}
4495 	},
4496 };
4497 
4498 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
4499 		struct inet6_dev *idev, struct ipv6_devconf *p)
4500 {
4501 	int i;
4502 	struct addrconf_sysctl_table *t;
4503 
4504 #define ADDRCONF_CTL_PATH_DEV	3
4505 
4506 	struct ctl_path addrconf_ctl_path[] = {
4507 		{ .procname = "net", },
4508 		{ .procname = "ipv6", },
4509 		{ .procname = "conf", },
4510 		{ /* to be set */ },
4511 		{ },
4512 	};
4513 
4514 
4515 	t = kmemdup(&addrconf_sysctl, sizeof(*t), GFP_KERNEL);
4516 	if (t == NULL)
4517 		goto out;
4518 
4519 	for (i = 0; t->addrconf_vars[i].data; i++) {
4520 		t->addrconf_vars[i].data += (char *)p - (char *)&ipv6_devconf;
4521 		t->addrconf_vars[i].extra1 = idev; /* embedded; no ref */
4522 		t->addrconf_vars[i].extra2 = net;
4523 	}
4524 
4525 	/*
4526 	 * Make a copy of dev_name, because '.procname' is regarded as const
4527 	 * by sysctl and we wouldn't want anyone to change it under our feet
4528 	 * (see SIOCSIFNAME).
4529 	 */
4530 	t->dev_name = kstrdup(dev_name, GFP_KERNEL);
4531 	if (!t->dev_name)
4532 		goto free;
4533 
4534 	addrconf_ctl_path[ADDRCONF_CTL_PATH_DEV].procname = t->dev_name;
4535 
4536 	t->sysctl_header = register_net_sysctl_table(net, addrconf_ctl_path,
4537 			t->addrconf_vars);
4538 	if (t->sysctl_header == NULL)
4539 		goto free_procname;
4540 
4541 	p->sysctl = t;
4542 	return 0;
4543 
4544 free_procname:
4545 	kfree(t->dev_name);
4546 free:
4547 	kfree(t);
4548 out:
4549 	return -ENOBUFS;
4550 }
4551 
4552 static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
4553 {
4554 	struct addrconf_sysctl_table *t;
4555 
4556 	if (p->sysctl == NULL)
4557 		return;
4558 
4559 	t = p->sysctl;
4560 	p->sysctl = NULL;
4561 	unregister_sysctl_table(t->sysctl_header);
4562 	kfree(t->dev_name);
4563 	kfree(t);
4564 }
4565 
4566 static void addrconf_sysctl_register(struct inet6_dev *idev)
4567 {
4568 	neigh_sysctl_register(idev->dev, idev->nd_parms, "ipv6",
4569 			      &ndisc_ifinfo_sysctl_change);
4570 	__addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
4571 					idev, &idev->cnf);
4572 }
4573 
4574 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
4575 {
4576 	__addrconf_sysctl_unregister(&idev->cnf);
4577 	neigh_sysctl_unregister(idev->nd_parms);
4578 }
4579 
4580 
4581 #endif
4582 
4583 static int __net_init addrconf_init_net(struct net *net)
4584 {
4585 	int err;
4586 	struct ipv6_devconf *all, *dflt;
4587 
4588 	err = -ENOMEM;
4589 	all = &ipv6_devconf;
4590 	dflt = &ipv6_devconf_dflt;
4591 
4592 	if (!net_eq(net, &init_net)) {
4593 		all = kmemdup(all, sizeof(ipv6_devconf), GFP_KERNEL);
4594 		if (all == NULL)
4595 			goto err_alloc_all;
4596 
4597 		dflt = kmemdup(dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
4598 		if (dflt == NULL)
4599 			goto err_alloc_dflt;
4600 	} else {
4601 		/* these will be inherited by all namespaces */
4602 		dflt->autoconf = ipv6_defaults.autoconf;
4603 		dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
4604 	}
4605 
4606 	net->ipv6.devconf_all = all;
4607 	net->ipv6.devconf_dflt = dflt;
4608 
4609 #ifdef CONFIG_SYSCTL
4610 	err = __addrconf_sysctl_register(net, "all", NULL, all);
4611 	if (err < 0)
4612 		goto err_reg_all;
4613 
4614 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
4615 	if (err < 0)
4616 		goto err_reg_dflt;
4617 #endif
4618 	return 0;
4619 
4620 #ifdef CONFIG_SYSCTL
4621 err_reg_dflt:
4622 	__addrconf_sysctl_unregister(all);
4623 err_reg_all:
4624 	kfree(dflt);
4625 #endif
4626 err_alloc_dflt:
4627 	kfree(all);
4628 err_alloc_all:
4629 	return err;
4630 }
4631 
4632 static void __net_exit addrconf_exit_net(struct net *net)
4633 {
4634 #ifdef CONFIG_SYSCTL
4635 	__addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
4636 	__addrconf_sysctl_unregister(net->ipv6.devconf_all);
4637 #endif
4638 	if (!net_eq(net, &init_net)) {
4639 		kfree(net->ipv6.devconf_dflt);
4640 		kfree(net->ipv6.devconf_all);
4641 	}
4642 }
4643 
4644 static struct pernet_operations addrconf_ops = {
4645 	.init = addrconf_init_net,
4646 	.exit = addrconf_exit_net,
4647 };
4648 
4649 /*
4650  *      Device notifier
4651  */
4652 
4653 int register_inet6addr_notifier(struct notifier_block *nb)
4654 {
4655 	return atomic_notifier_chain_register(&inet6addr_chain, nb);
4656 }
4657 EXPORT_SYMBOL(register_inet6addr_notifier);
4658 
4659 int unregister_inet6addr_notifier(struct notifier_block *nb)
4660 {
4661 	return atomic_notifier_chain_unregister(&inet6addr_chain, nb);
4662 }
4663 EXPORT_SYMBOL(unregister_inet6addr_notifier);
4664 
4665 static struct rtnl_af_ops inet6_ops = {
4666 	.family		  = AF_INET6,
4667 	.fill_link_af	  = inet6_fill_link_af,
4668 	.get_link_af_size = inet6_get_link_af_size,
4669 };
4670 
4671 /*
4672  *	Init / cleanup code
4673  */
4674 
4675 int __init addrconf_init(void)
4676 {
4677 	int i, err;
4678 
4679 	err = ipv6_addr_label_init();
4680 	if (err < 0) {
4681 		printk(KERN_CRIT "IPv6 Addrconf:"
4682 		       " cannot initialize default policy table: %d.\n", err);
4683 		goto out;
4684 	}
4685 
4686 	err = register_pernet_subsys(&addrconf_ops);
4687 	if (err < 0)
4688 		goto out_addrlabel;
4689 
4690 	/* The addrconf netdev notifier requires that loopback_dev
4691 	 * has it's ipv6 private information allocated and setup
4692 	 * before it can bring up and give link-local addresses
4693 	 * to other devices which are up.
4694 	 *
4695 	 * Unfortunately, loopback_dev is not necessarily the first
4696 	 * entry in the global dev_base list of net devices.  In fact,
4697 	 * it is likely to be the very last entry on that list.
4698 	 * So this causes the notifier registry below to try and
4699 	 * give link-local addresses to all devices besides loopback_dev
4700 	 * first, then loopback_dev, which cases all the non-loopback_dev
4701 	 * devices to fail to get a link-local address.
4702 	 *
4703 	 * So, as a temporary fix, allocate the ipv6 structure for
4704 	 * loopback_dev first by hand.
4705 	 * Longer term, all of the dependencies ipv6 has upon the loopback
4706 	 * device and it being up should be removed.
4707 	 */
4708 	rtnl_lock();
4709 	if (!ipv6_add_dev(init_net.loopback_dev))
4710 		err = -ENOMEM;
4711 	rtnl_unlock();
4712 	if (err)
4713 		goto errlo;
4714 
4715 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
4716 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
4717 
4718 	register_netdevice_notifier(&ipv6_dev_notf);
4719 
4720 	addrconf_verify(0);
4721 
4722 	err = rtnl_af_register(&inet6_ops);
4723 	if (err < 0)
4724 		goto errout_af;
4725 
4726 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo);
4727 	if (err < 0)
4728 		goto errout;
4729 
4730 	/* Only the first call to __rtnl_register can fail */
4731 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL);
4732 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL);
4733 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr, inet6_dump_ifaddr);
4734 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL, inet6_dump_ifmcaddr);
4735 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL, inet6_dump_ifacaddr);
4736 
4737 	ipv6_addr_label_rtnl_register();
4738 
4739 	return 0;
4740 errout:
4741 	rtnl_af_unregister(&inet6_ops);
4742 errout_af:
4743 	unregister_netdevice_notifier(&ipv6_dev_notf);
4744 errlo:
4745 	unregister_pernet_subsys(&addrconf_ops);
4746 out_addrlabel:
4747 	ipv6_addr_label_cleanup();
4748 out:
4749 	return err;
4750 }
4751 
4752 void addrconf_cleanup(void)
4753 {
4754 	struct net_device *dev;
4755 	int i;
4756 
4757 	unregister_netdevice_notifier(&ipv6_dev_notf);
4758 	unregister_pernet_subsys(&addrconf_ops);
4759 	ipv6_addr_label_cleanup();
4760 
4761 	rtnl_lock();
4762 
4763 	__rtnl_af_unregister(&inet6_ops);
4764 
4765 	/* clean dev list */
4766 	for_each_netdev(&init_net, dev) {
4767 		if (__in6_dev_get(dev) == NULL)
4768 			continue;
4769 		addrconf_ifdown(dev, 1);
4770 	}
4771 	addrconf_ifdown(init_net.loopback_dev, 2);
4772 
4773 	/*
4774 	 *	Check hash table.
4775 	 */
4776 	spin_lock_bh(&addrconf_hash_lock);
4777 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
4778 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
4779 	spin_unlock_bh(&addrconf_hash_lock);
4780 
4781 	del_timer(&addr_chk_timer);
4782 	rtnl_unlock();
4783 }
4784