xref: /linux/net/ipv6/addrconf.c (revision a58130ddc896e5a15e4de2bf50a1d89247118c23)
1 /*
2  *	IPv6 Address [auto]configuration
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
8  *
9  *	This program is free software; you can redistribute it and/or
10  *      modify it under the terms of the GNU General Public License
11  *      as published by the Free Software Foundation; either version
12  *      2 of the License, or (at your option) any later version.
13  */
14 
15 /*
16  *	Changes:
17  *
18  *	Janos Farkas			:	delete timer on ifdown
19  *	<chexum@bankinf.banki.hu>
20  *	Andi Kleen			:	kill double kfree on module
21  *						unload.
22  *	Maciej W. Rozycki		:	FDDI support
23  *	sekiya@USAGI			:	Don't send too many RS
24  *						packets.
25  *	yoshfuji@USAGI			:       Fixed interval between DAD
26  *						packets.
27  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
28  *						address validation timer.
29  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
30  *						support.
31  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
32  *						address on a same interface.
33  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
34  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
35  *						seq_file.
36  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
37  *						selection; consider scope,
38  *						status etc.
39  */
40 
41 #define pr_fmt(fmt) "IPv6: " fmt
42 
43 #include <linux/errno.h>
44 #include <linux/types.h>
45 #include <linux/kernel.h>
46 #include <linux/socket.h>
47 #include <linux/sockios.h>
48 #include <linux/net.h>
49 #include <linux/in6.h>
50 #include <linux/netdevice.h>
51 #include <linux/if_addr.h>
52 #include <linux/if_arp.h>
53 #include <linux/if_arcnet.h>
54 #include <linux/if_infiniband.h>
55 #include <linux/route.h>
56 #include <linux/inetdevice.h>
57 #include <linux/init.h>
58 #include <linux/slab.h>
59 #ifdef CONFIG_SYSCTL
60 #include <linux/sysctl.h>
61 #endif
62 #include <linux/capability.h>
63 #include <linux/delay.h>
64 #include <linux/notifier.h>
65 #include <linux/string.h>
66 #include <linux/hash.h>
67 
68 #include <net/net_namespace.h>
69 #include <net/sock.h>
70 #include <net/snmp.h>
71 
72 #include <net/af_ieee802154.h>
73 #include <net/ipv6.h>
74 #include <net/protocol.h>
75 #include <net/ndisc.h>
76 #include <net/ip6_route.h>
77 #include <net/addrconf.h>
78 #include <net/tcp.h>
79 #include <net/ip.h>
80 #include <net/netlink.h>
81 #include <net/pkt_sched.h>
82 #include <linux/if_tunnel.h>
83 #include <linux/rtnetlink.h>
84 #include <linux/netconf.h>
85 
86 #ifdef CONFIG_IPV6_PRIVACY
87 #include <linux/random.h>
88 #endif
89 
90 #include <linux/uaccess.h>
91 #include <asm/unaligned.h>
92 
93 #include <linux/proc_fs.h>
94 #include <linux/seq_file.h>
95 #include <linux/export.h>
96 
97 /* Set to 3 to get tracing... */
98 #define ACONF_DEBUG 2
99 
100 #if ACONF_DEBUG >= 3
101 #define ADBG(x) printk x
102 #else
103 #define ADBG(x)
104 #endif
105 
106 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
107 
108 static inline u32 cstamp_delta(unsigned long cstamp)
109 {
110 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
111 }
112 
113 #define ADDRCONF_TIMER_FUZZ_MINUS	(HZ > 50 ? HZ/50 : 1)
114 #define ADDRCONF_TIMER_FUZZ		(HZ / 4)
115 #define ADDRCONF_TIMER_FUZZ_MAX		(HZ)
116 
117 #ifdef CONFIG_SYSCTL
118 static void addrconf_sysctl_register(struct inet6_dev *idev);
119 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
120 #else
121 static inline void addrconf_sysctl_register(struct inet6_dev *idev)
122 {
123 }
124 
125 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
126 {
127 }
128 #endif
129 
130 #ifdef CONFIG_IPV6_PRIVACY
131 static void __ipv6_regen_rndid(struct inet6_dev *idev);
132 static void __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
133 static void ipv6_regen_rndid(unsigned long data);
134 #endif
135 
136 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
137 static int ipv6_count_addresses(struct inet6_dev *idev);
138 
139 /*
140  *	Configured unicast address hash table
141  */
142 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
143 static DEFINE_SPINLOCK(addrconf_hash_lock);
144 
145 static void addrconf_verify(unsigned long);
146 
147 static DEFINE_TIMER(addr_chk_timer, addrconf_verify, 0, 0);
148 static DEFINE_SPINLOCK(addrconf_verify_lock);
149 
150 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
151 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
152 
153 static void addrconf_type_change(struct net_device *dev,
154 				 unsigned long event);
155 static int addrconf_ifdown(struct net_device *dev, int how);
156 
157 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
158 static void addrconf_dad_timer(unsigned long data);
159 static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
160 static void addrconf_dad_run(struct inet6_dev *idev);
161 static void addrconf_rs_timer(unsigned long data);
162 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
163 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
164 
165 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
166 				struct prefix_info *pinfo);
167 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
168 			       struct net_device *dev);
169 
170 static ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
171 
172 static struct ipv6_devconf ipv6_devconf __read_mostly = {
173 	.forwarding		= 0,
174 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
175 	.mtu6			= IPV6_MIN_MTU,
176 	.accept_ra		= 1,
177 	.accept_redirects	= 1,
178 	.autoconf		= 1,
179 	.force_mld_version	= 0,
180 	.dad_transmits		= 1,
181 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
182 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
183 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
184 #ifdef CONFIG_IPV6_PRIVACY
185 	.use_tempaddr 		= 0,
186 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
187 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
188 	.regen_max_retry	= REGEN_MAX_RETRY,
189 	.max_desync_factor	= MAX_DESYNC_FACTOR,
190 #endif
191 	.max_addresses		= IPV6_MAX_ADDRESSES,
192 	.accept_ra_defrtr	= 1,
193 	.accept_ra_pinfo	= 1,
194 #ifdef CONFIG_IPV6_ROUTER_PREF
195 	.accept_ra_rtr_pref	= 1,
196 	.rtr_probe_interval	= 60 * HZ,
197 #ifdef CONFIG_IPV6_ROUTE_INFO
198 	.accept_ra_rt_info_max_plen = 0,
199 #endif
200 #endif
201 	.proxy_ndp		= 0,
202 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
203 	.disable_ipv6		= 0,
204 	.accept_dad		= 1,
205 };
206 
207 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
208 	.forwarding		= 0,
209 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
210 	.mtu6			= IPV6_MIN_MTU,
211 	.accept_ra		= 1,
212 	.accept_redirects	= 1,
213 	.autoconf		= 1,
214 	.dad_transmits		= 1,
215 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
216 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
217 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
218 #ifdef CONFIG_IPV6_PRIVACY
219 	.use_tempaddr		= 0,
220 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
221 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
222 	.regen_max_retry	= REGEN_MAX_RETRY,
223 	.max_desync_factor	= MAX_DESYNC_FACTOR,
224 #endif
225 	.max_addresses		= IPV6_MAX_ADDRESSES,
226 	.accept_ra_defrtr	= 1,
227 	.accept_ra_pinfo	= 1,
228 #ifdef CONFIG_IPV6_ROUTER_PREF
229 	.accept_ra_rtr_pref	= 1,
230 	.rtr_probe_interval	= 60 * HZ,
231 #ifdef CONFIG_IPV6_ROUTE_INFO
232 	.accept_ra_rt_info_max_plen = 0,
233 #endif
234 #endif
235 	.proxy_ndp		= 0,
236 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
237 	.disable_ipv6		= 0,
238 	.accept_dad		= 1,
239 };
240 
241 /* IPv6 Wildcard Address and Loopback Address defined by RFC2553 */
242 const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
243 const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
244 const struct in6_addr in6addr_linklocal_allnodes = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
245 const struct in6_addr in6addr_linklocal_allrouters = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
246 
247 /* Check if a valid qdisc is available */
248 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
249 {
250 	return !qdisc_tx_is_noop(dev);
251 }
252 
253 /* Check if a route is valid prefix route */
254 static inline int addrconf_is_prefix_route(const struct rt6_info *rt)
255 {
256 	return (rt->rt6i_flags & (RTF_GATEWAY | RTF_DEFAULT)) == 0;
257 }
258 
259 static void addrconf_del_timer(struct inet6_ifaddr *ifp)
260 {
261 	if (del_timer(&ifp->timer))
262 		__in6_ifa_put(ifp);
263 }
264 
265 enum addrconf_timer_t {
266 	AC_NONE,
267 	AC_DAD,
268 	AC_RS,
269 };
270 
271 static void addrconf_mod_timer(struct inet6_ifaddr *ifp,
272 			       enum addrconf_timer_t what,
273 			       unsigned long when)
274 {
275 	if (!del_timer(&ifp->timer))
276 		in6_ifa_hold(ifp);
277 
278 	switch (what) {
279 	case AC_DAD:
280 		ifp->timer.function = addrconf_dad_timer;
281 		break;
282 	case AC_RS:
283 		ifp->timer.function = addrconf_rs_timer;
284 		break;
285 	default:
286 		break;
287 	}
288 	ifp->timer.expires = jiffies + when;
289 	add_timer(&ifp->timer);
290 }
291 
292 static int snmp6_alloc_dev(struct inet6_dev *idev)
293 {
294 	if (snmp_mib_init((void __percpu **)idev->stats.ipv6,
295 			  sizeof(struct ipstats_mib),
296 			  __alignof__(struct ipstats_mib)) < 0)
297 		goto err_ip;
298 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
299 					GFP_KERNEL);
300 	if (!idev->stats.icmpv6dev)
301 		goto err_icmp;
302 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
303 					   GFP_KERNEL);
304 	if (!idev->stats.icmpv6msgdev)
305 		goto err_icmpmsg;
306 
307 	return 0;
308 
309 err_icmpmsg:
310 	kfree(idev->stats.icmpv6dev);
311 err_icmp:
312 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
313 err_ip:
314 	return -ENOMEM;
315 }
316 
317 static void snmp6_free_dev(struct inet6_dev *idev)
318 {
319 	kfree(idev->stats.icmpv6msgdev);
320 	kfree(idev->stats.icmpv6dev);
321 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
322 }
323 
324 /* Nobody refers to this device, we may destroy it. */
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 	pr_debug("%s: %s\n", __func__, dev ? dev->name : "NIL");
335 #endif
336 	dev_put(dev);
337 	if (!idev->dead) {
338 		pr_warn("Freeing alive inet6 device %p\n", idev);
339 		return;
340 	}
341 	snmp6_free_dev(idev);
342 	kfree_rcu(idev, rcu);
343 }
344 EXPORT_SYMBOL(in6_dev_finish_destroy);
345 
346 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
347 {
348 	struct inet6_dev *ndev;
349 
350 	ASSERT_RTNL();
351 
352 	if (dev->mtu < IPV6_MIN_MTU)
353 		return NULL;
354 
355 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
356 
357 	if (ndev == NULL)
358 		return NULL;
359 
360 	rwlock_init(&ndev->lock);
361 	ndev->dev = dev;
362 	INIT_LIST_HEAD(&ndev->addr_list);
363 
364 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
365 	ndev->cnf.mtu6 = dev->mtu;
366 	ndev->cnf.sysctl = NULL;
367 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
368 	if (ndev->nd_parms == NULL) {
369 		kfree(ndev);
370 		return NULL;
371 	}
372 	if (ndev->cnf.forwarding)
373 		dev_disable_lro(dev);
374 	/* We refer to the device */
375 	dev_hold(dev);
376 
377 	if (snmp6_alloc_dev(ndev) < 0) {
378 		ADBG((KERN_WARNING
379 			"%s: cannot allocate memory for statistics; dev=%s.\n",
380 			__func__, dev->name));
381 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
382 		dev_put(dev);
383 		kfree(ndev);
384 		return NULL;
385 	}
386 
387 	if (snmp6_register_dev(ndev) < 0) {
388 		ADBG((KERN_WARNING
389 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
390 			__func__, dev->name));
391 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
392 		ndev->dead = 1;
393 		in6_dev_finish_destroy(ndev);
394 		return NULL;
395 	}
396 
397 	/* One reference from device.  We must do this before
398 	 * we invoke __ipv6_regen_rndid().
399 	 */
400 	in6_dev_hold(ndev);
401 
402 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
403 		ndev->cnf.accept_dad = -1;
404 
405 #if IS_ENABLED(CONFIG_IPV6_SIT)
406 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
407 		pr_info("%s: Disabled Multicast RS\n", dev->name);
408 		ndev->cnf.rtr_solicits = 0;
409 	}
410 #endif
411 
412 #ifdef CONFIG_IPV6_PRIVACY
413 	INIT_LIST_HEAD(&ndev->tempaddr_list);
414 	setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
415 	if ((dev->flags&IFF_LOOPBACK) ||
416 	    dev->type == ARPHRD_TUNNEL ||
417 	    dev->type == ARPHRD_TUNNEL6 ||
418 	    dev->type == ARPHRD_SIT ||
419 	    dev->type == ARPHRD_NONE) {
420 		ndev->cnf.use_tempaddr = -1;
421 	} else {
422 		in6_dev_hold(ndev);
423 		ipv6_regen_rndid((unsigned long) ndev);
424 	}
425 #endif
426 
427 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
428 		ndev->if_flags |= IF_READY;
429 
430 	ipv6_mc_init_dev(ndev);
431 	ndev->tstamp = jiffies;
432 	addrconf_sysctl_register(ndev);
433 	/* protected by rtnl_lock */
434 	rcu_assign_pointer(dev->ip6_ptr, ndev);
435 
436 	/* Join all-node multicast group */
437 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
438 
439 	/* Join all-router multicast group if forwarding is set */
440 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
441 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
442 
443 	return ndev;
444 }
445 
446 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
447 {
448 	struct inet6_dev *idev;
449 
450 	ASSERT_RTNL();
451 
452 	idev = __in6_dev_get(dev);
453 	if (!idev) {
454 		idev = ipv6_add_dev(dev);
455 		if (!idev)
456 			return NULL;
457 	}
458 
459 	if (dev->flags&IFF_UP)
460 		ipv6_mc_up(idev);
461 	return idev;
462 }
463 
464 static int inet6_netconf_msgsize_devconf(int type)
465 {
466 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
467 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
468 
469 	/* type -1 is used for ALL */
470 	if (type == -1 || type == NETCONFA_FORWARDING)
471 		size += nla_total_size(4);
472 #ifdef CONFIG_IPV6_MROUTE
473 	if (type == -1 || type == NETCONFA_MC_FORWARDING)
474 		size += nla_total_size(4);
475 #endif
476 
477 	return size;
478 }
479 
480 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
481 				      struct ipv6_devconf *devconf, u32 portid,
482 				      u32 seq, int event, unsigned int flags,
483 				      int type)
484 {
485 	struct nlmsghdr  *nlh;
486 	struct netconfmsg *ncm;
487 
488 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
489 			flags);
490 	if (nlh == NULL)
491 		return -EMSGSIZE;
492 
493 	ncm = nlmsg_data(nlh);
494 	ncm->ncm_family = AF_INET6;
495 
496 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
497 		goto nla_put_failure;
498 
499 	/* type -1 is used for ALL */
500 	if ((type == -1 || type == NETCONFA_FORWARDING) &&
501 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
502 		goto nla_put_failure;
503 #ifdef CONFIG_IPV6_MROUTE
504 	if ((type == -1 || type == NETCONFA_MC_FORWARDING) &&
505 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
506 			devconf->mc_forwarding) < 0)
507 		goto nla_put_failure;
508 #endif
509 	return nlmsg_end(skb, nlh);
510 
511 nla_put_failure:
512 	nlmsg_cancel(skb, nlh);
513 	return -EMSGSIZE;
514 }
515 
516 void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
517 				  struct ipv6_devconf *devconf)
518 {
519 	struct sk_buff *skb;
520 	int err = -ENOBUFS;
521 
522 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_ATOMIC);
523 	if (skb == NULL)
524 		goto errout;
525 
526 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
527 					 RTM_NEWNETCONF, 0, type);
528 	if (err < 0) {
529 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
530 		WARN_ON(err == -EMSGSIZE);
531 		kfree_skb(skb);
532 		goto errout;
533 	}
534 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_ATOMIC);
535 	return;
536 errout:
537 	if (err < 0)
538 		rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
539 }
540 
541 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
542 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
543 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
544 };
545 
546 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
547 				     struct nlmsghdr *nlh,
548 				     void *arg)
549 {
550 	struct net *net = sock_net(in_skb->sk);
551 	struct nlattr *tb[NETCONFA_MAX+1];
552 	struct netconfmsg *ncm;
553 	struct sk_buff *skb;
554 	struct ipv6_devconf *devconf;
555 	struct inet6_dev *in6_dev;
556 	struct net_device *dev;
557 	int ifindex;
558 	int err;
559 
560 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
561 			  devconf_ipv6_policy);
562 	if (err < 0)
563 		goto errout;
564 
565 	err = EINVAL;
566 	if (!tb[NETCONFA_IFINDEX])
567 		goto errout;
568 
569 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
570 	switch (ifindex) {
571 	case NETCONFA_IFINDEX_ALL:
572 		devconf = net->ipv6.devconf_all;
573 		break;
574 	case NETCONFA_IFINDEX_DEFAULT:
575 		devconf = net->ipv6.devconf_dflt;
576 		break;
577 	default:
578 		dev = __dev_get_by_index(net, ifindex);
579 		if (dev == NULL)
580 			goto errout;
581 		in6_dev = __in6_dev_get(dev);
582 		if (in6_dev == NULL)
583 			goto errout;
584 		devconf = &in6_dev->cnf;
585 		break;
586 	}
587 
588 	err = -ENOBUFS;
589 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(-1), GFP_ATOMIC);
590 	if (skb == NULL)
591 		goto errout;
592 
593 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
594 					 NETLINK_CB(in_skb).portid,
595 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
596 					 -1);
597 	if (err < 0) {
598 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
599 		WARN_ON(err == -EMSGSIZE);
600 		kfree_skb(skb);
601 		goto errout;
602 	}
603 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
604 errout:
605 	return err;
606 }
607 
608 #ifdef CONFIG_SYSCTL
609 static void dev_forward_change(struct inet6_dev *idev)
610 {
611 	struct net_device *dev;
612 	struct inet6_ifaddr *ifa;
613 
614 	if (!idev)
615 		return;
616 	dev = idev->dev;
617 	if (idev->cnf.forwarding)
618 		dev_disable_lro(dev);
619 	if (dev->flags & IFF_MULTICAST) {
620 		if (idev->cnf.forwarding)
621 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
622 		else
623 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
624 	}
625 
626 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
627 		if (ifa->flags&IFA_F_TENTATIVE)
628 			continue;
629 		if (idev->cnf.forwarding)
630 			addrconf_join_anycast(ifa);
631 		else
632 			addrconf_leave_anycast(ifa);
633 	}
634 	inet6_netconf_notify_devconf(dev_net(dev), NETCONFA_FORWARDING,
635 				     dev->ifindex, &idev->cnf);
636 }
637 
638 
639 static void addrconf_forward_change(struct net *net, __s32 newf)
640 {
641 	struct net_device *dev;
642 	struct inet6_dev *idev;
643 
644 	for_each_netdev(net, dev) {
645 		idev = __in6_dev_get(dev);
646 		if (idev) {
647 			int changed = (!idev->cnf.forwarding) ^ (!newf);
648 			idev->cnf.forwarding = newf;
649 			if (changed)
650 				dev_forward_change(idev);
651 		}
652 	}
653 }
654 
655 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
656 {
657 	struct net *net;
658 	int old;
659 
660 	if (!rtnl_trylock())
661 		return restart_syscall();
662 
663 	net = (struct net *)table->extra2;
664 	old = *p;
665 	*p = newf;
666 
667 	if (p == &net->ipv6.devconf_dflt->forwarding) {
668 		if ((!newf) ^ (!old))
669 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
670 						     NETCONFA_IFINDEX_DEFAULT,
671 						     net->ipv6.devconf_dflt);
672 		rtnl_unlock();
673 		return 0;
674 	}
675 
676 	if (p == &net->ipv6.devconf_all->forwarding) {
677 		net->ipv6.devconf_dflt->forwarding = newf;
678 		addrconf_forward_change(net, newf);
679 		if ((!newf) ^ (!old))
680 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
681 						     NETCONFA_IFINDEX_ALL,
682 						     net->ipv6.devconf_all);
683 	} else if ((!newf) ^ (!old))
684 		dev_forward_change((struct inet6_dev *)table->extra1);
685 	rtnl_unlock();
686 
687 	if (newf)
688 		rt6_purge_dflt_routers(net);
689 	return 1;
690 }
691 #endif
692 
693 /* Nobody refers to this ifaddr, destroy it */
694 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
695 {
696 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
697 
698 #ifdef NET_REFCNT_DEBUG
699 	pr_debug("%s\n", __func__);
700 #endif
701 
702 	in6_dev_put(ifp->idev);
703 
704 	if (del_timer(&ifp->timer))
705 		pr_notice("Timer is still running, when freeing ifa=%p\n", ifp);
706 
707 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
708 		pr_warn("Freeing alive inet6 address %p\n", ifp);
709 		return;
710 	}
711 	ip6_rt_put(ifp->rt);
712 
713 	kfree_rcu(ifp, rcu);
714 }
715 
716 static void
717 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
718 {
719 	struct list_head *p;
720 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
721 
722 	/*
723 	 * Each device address list is sorted in order of scope -
724 	 * global before linklocal.
725 	 */
726 	list_for_each(p, &idev->addr_list) {
727 		struct inet6_ifaddr *ifa
728 			= list_entry(p, struct inet6_ifaddr, if_list);
729 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
730 			break;
731 	}
732 
733 	list_add_tail(&ifp->if_list, p);
734 }
735 
736 static u32 inet6_addr_hash(const struct in6_addr *addr)
737 {
738 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
739 }
740 
741 /* On success it returns ifp with increased reference count */
742 
743 static struct inet6_ifaddr *
744 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen,
745 	      int scope, u32 flags)
746 {
747 	struct inet6_ifaddr *ifa = NULL;
748 	struct rt6_info *rt;
749 	unsigned int hash;
750 	int err = 0;
751 	int addr_type = ipv6_addr_type(addr);
752 
753 	if (addr_type == IPV6_ADDR_ANY ||
754 	    addr_type & IPV6_ADDR_MULTICAST ||
755 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
756 	     addr_type & IPV6_ADDR_LOOPBACK))
757 		return ERR_PTR(-EADDRNOTAVAIL);
758 
759 	rcu_read_lock_bh();
760 	if (idev->dead) {
761 		err = -ENODEV;			/*XXX*/
762 		goto out2;
763 	}
764 
765 	if (idev->cnf.disable_ipv6) {
766 		err = -EACCES;
767 		goto out2;
768 	}
769 
770 	spin_lock(&addrconf_hash_lock);
771 
772 	/* Ignore adding duplicate addresses on an interface */
773 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
774 		ADBG(("ipv6_add_addr: already assigned\n"));
775 		err = -EEXIST;
776 		goto out;
777 	}
778 
779 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
780 
781 	if (ifa == NULL) {
782 		ADBG(("ipv6_add_addr: malloc failed\n"));
783 		err = -ENOBUFS;
784 		goto out;
785 	}
786 
787 	rt = addrconf_dst_alloc(idev, addr, false);
788 	if (IS_ERR(rt)) {
789 		err = PTR_ERR(rt);
790 		goto out;
791 	}
792 
793 	ifa->addr = *addr;
794 
795 	spin_lock_init(&ifa->lock);
796 	spin_lock_init(&ifa->state_lock);
797 	init_timer(&ifa->timer);
798 	INIT_HLIST_NODE(&ifa->addr_lst);
799 	ifa->timer.data = (unsigned long) ifa;
800 	ifa->scope = scope;
801 	ifa->prefix_len = pfxlen;
802 	ifa->flags = flags | IFA_F_TENTATIVE;
803 	ifa->cstamp = ifa->tstamp = jiffies;
804 
805 	ifa->rt = rt;
806 
807 	ifa->idev = idev;
808 	in6_dev_hold(idev);
809 	/* For caller */
810 	in6_ifa_hold(ifa);
811 
812 	/* Add to big hash table */
813 	hash = inet6_addr_hash(addr);
814 
815 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
816 	spin_unlock(&addrconf_hash_lock);
817 
818 	write_lock(&idev->lock);
819 	/* Add to inet6_dev unicast addr list. */
820 	ipv6_link_dev_addr(idev, ifa);
821 
822 #ifdef CONFIG_IPV6_PRIVACY
823 	if (ifa->flags&IFA_F_TEMPORARY) {
824 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
825 		in6_ifa_hold(ifa);
826 	}
827 #endif
828 
829 	in6_ifa_hold(ifa);
830 	write_unlock(&idev->lock);
831 out2:
832 	rcu_read_unlock_bh();
833 
834 	if (likely(err == 0))
835 		atomic_notifier_call_chain(&inet6addr_chain, NETDEV_UP, ifa);
836 	else {
837 		kfree(ifa);
838 		ifa = ERR_PTR(err);
839 	}
840 
841 	return ifa;
842 out:
843 	spin_unlock(&addrconf_hash_lock);
844 	goto out2;
845 }
846 
847 /* This function wants to get referenced ifp and releases it before return */
848 
849 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
850 {
851 	struct inet6_ifaddr *ifa, *ifn;
852 	struct inet6_dev *idev = ifp->idev;
853 	int state;
854 	int deleted = 0, onlink = 0;
855 	unsigned long expires = jiffies;
856 
857 	spin_lock_bh(&ifp->state_lock);
858 	state = ifp->state;
859 	ifp->state = INET6_IFADDR_STATE_DEAD;
860 	spin_unlock_bh(&ifp->state_lock);
861 
862 	if (state == INET6_IFADDR_STATE_DEAD)
863 		goto out;
864 
865 	spin_lock_bh(&addrconf_hash_lock);
866 	hlist_del_init_rcu(&ifp->addr_lst);
867 	spin_unlock_bh(&addrconf_hash_lock);
868 
869 	write_lock_bh(&idev->lock);
870 #ifdef CONFIG_IPV6_PRIVACY
871 	if (ifp->flags&IFA_F_TEMPORARY) {
872 		list_del(&ifp->tmp_list);
873 		if (ifp->ifpub) {
874 			in6_ifa_put(ifp->ifpub);
875 			ifp->ifpub = NULL;
876 		}
877 		__in6_ifa_put(ifp);
878 	}
879 #endif
880 
881 	list_for_each_entry_safe(ifa, ifn, &idev->addr_list, if_list) {
882 		if (ifa == ifp) {
883 			list_del_init(&ifp->if_list);
884 			__in6_ifa_put(ifp);
885 
886 			if (!(ifp->flags & IFA_F_PERMANENT) || onlink > 0)
887 				break;
888 			deleted = 1;
889 			continue;
890 		} else if (ifp->flags & IFA_F_PERMANENT) {
891 			if (ipv6_prefix_equal(&ifa->addr, &ifp->addr,
892 					      ifp->prefix_len)) {
893 				if (ifa->flags & IFA_F_PERMANENT) {
894 					onlink = 1;
895 					if (deleted)
896 						break;
897 				} else {
898 					unsigned long lifetime;
899 
900 					if (!onlink)
901 						onlink = -1;
902 
903 					spin_lock(&ifa->lock);
904 
905 					lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
906 					/*
907 					 * Note: Because this address is
908 					 * not permanent, lifetime <
909 					 * LONG_MAX / HZ here.
910 					 */
911 					if (time_before(expires,
912 							ifa->tstamp + lifetime * HZ))
913 						expires = ifa->tstamp + lifetime * HZ;
914 					spin_unlock(&ifa->lock);
915 				}
916 			}
917 		}
918 	}
919 	write_unlock_bh(&idev->lock);
920 
921 	addrconf_del_timer(ifp);
922 
923 	ipv6_ifa_notify(RTM_DELADDR, ifp);
924 
925 	atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifp);
926 
927 	/*
928 	 * Purge or update corresponding prefix
929 	 *
930 	 * 1) we don't purge prefix here if address was not permanent.
931 	 *    prefix is managed by its own lifetime.
932 	 * 2) if there're no addresses, delete prefix.
933 	 * 3) if there're still other permanent address(es),
934 	 *    corresponding prefix is still permanent.
935 	 * 4) otherwise, update prefix lifetime to the
936 	 *    longest valid lifetime among the corresponding
937 	 *    addresses on the device.
938 	 *    Note: subsequent RA will update lifetime.
939 	 *
940 	 * --yoshfuji
941 	 */
942 	if ((ifp->flags & IFA_F_PERMANENT) && onlink < 1) {
943 		struct in6_addr prefix;
944 		struct rt6_info *rt;
945 		struct net *net = dev_net(ifp->idev->dev);
946 		struct flowi6 fl6 = {};
947 
948 		ipv6_addr_prefix(&prefix, &ifp->addr, ifp->prefix_len);
949 		fl6.flowi6_oif = ifp->idev->dev->ifindex;
950 		fl6.daddr = prefix;
951 		rt = (struct rt6_info *)ip6_route_lookup(net, &fl6,
952 							 RT6_LOOKUP_F_IFACE);
953 
954 		if (rt != net->ipv6.ip6_null_entry &&
955 		    addrconf_is_prefix_route(rt)) {
956 			if (onlink == 0) {
957 				ip6_del_rt(rt);
958 				rt = NULL;
959 			} else if (!(rt->rt6i_flags & RTF_EXPIRES)) {
960 				rt6_set_expires(rt, expires);
961 			}
962 		}
963 		ip6_rt_put(rt);
964 	}
965 
966 	/* clean up prefsrc entries */
967 	rt6_remove_prefsrc(ifp);
968 out:
969 	in6_ifa_put(ifp);
970 }
971 
972 #ifdef CONFIG_IPV6_PRIVACY
973 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
974 {
975 	struct inet6_dev *idev = ifp->idev;
976 	struct in6_addr addr, *tmpaddr;
977 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
978 	unsigned long regen_advance;
979 	int tmp_plen;
980 	int ret = 0;
981 	int max_addresses;
982 	u32 addr_flags;
983 	unsigned long now = jiffies;
984 
985 	write_lock(&idev->lock);
986 	if (ift) {
987 		spin_lock_bh(&ift->lock);
988 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
989 		spin_unlock_bh(&ift->lock);
990 		tmpaddr = &addr;
991 	} else {
992 		tmpaddr = NULL;
993 	}
994 retry:
995 	in6_dev_hold(idev);
996 	if (idev->cnf.use_tempaddr <= 0) {
997 		write_unlock(&idev->lock);
998 		pr_info("%s: use_tempaddr is disabled\n", __func__);
999 		in6_dev_put(idev);
1000 		ret = -1;
1001 		goto out;
1002 	}
1003 	spin_lock_bh(&ifp->lock);
1004 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1005 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1006 		spin_unlock_bh(&ifp->lock);
1007 		write_unlock(&idev->lock);
1008 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1009 			__func__);
1010 		in6_dev_put(idev);
1011 		ret = -1;
1012 		goto out;
1013 	}
1014 	in6_ifa_hold(ifp);
1015 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1016 	__ipv6_try_regen_rndid(idev, tmpaddr);
1017 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1018 	age = (now - ifp->tstamp) / HZ;
1019 	tmp_valid_lft = min_t(__u32,
1020 			      ifp->valid_lft,
1021 			      idev->cnf.temp_valid_lft + age);
1022 	tmp_prefered_lft = min_t(__u32,
1023 				 ifp->prefered_lft,
1024 				 idev->cnf.temp_prefered_lft + age -
1025 				 idev->cnf.max_desync_factor);
1026 	tmp_plen = ifp->prefix_len;
1027 	max_addresses = idev->cnf.max_addresses;
1028 	tmp_tstamp = ifp->tstamp;
1029 	spin_unlock_bh(&ifp->lock);
1030 
1031 	regen_advance = idev->cnf.regen_max_retry *
1032 	                idev->cnf.dad_transmits *
1033 	                idev->nd_parms->retrans_time / HZ;
1034 	write_unlock(&idev->lock);
1035 
1036 	/* A temporary address is created only if this calculated Preferred
1037 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1038 	 * an implementation must not create a temporary address with a zero
1039 	 * Preferred Lifetime.
1040 	 */
1041 	if (tmp_prefered_lft <= regen_advance) {
1042 		in6_ifa_put(ifp);
1043 		in6_dev_put(idev);
1044 		ret = -1;
1045 		goto out;
1046 	}
1047 
1048 	addr_flags = IFA_F_TEMPORARY;
1049 	/* set in addrconf_prefix_rcv() */
1050 	if (ifp->flags & IFA_F_OPTIMISTIC)
1051 		addr_flags |= IFA_F_OPTIMISTIC;
1052 
1053 	ift = !max_addresses ||
1054 	      ipv6_count_addresses(idev) < max_addresses ?
1055 		ipv6_add_addr(idev, &addr, tmp_plen,
1056 			      ipv6_addr_type(&addr)&IPV6_ADDR_SCOPE_MASK,
1057 			      addr_flags) : NULL;
1058 	if (!ift || IS_ERR(ift)) {
1059 		in6_ifa_put(ifp);
1060 		in6_dev_put(idev);
1061 		pr_info("%s: retry temporary address regeneration\n", __func__);
1062 		tmpaddr = &addr;
1063 		write_lock(&idev->lock);
1064 		goto retry;
1065 	}
1066 
1067 	spin_lock_bh(&ift->lock);
1068 	ift->ifpub = ifp;
1069 	ift->valid_lft = tmp_valid_lft;
1070 	ift->prefered_lft = tmp_prefered_lft;
1071 	ift->cstamp = now;
1072 	ift->tstamp = tmp_tstamp;
1073 	spin_unlock_bh(&ift->lock);
1074 
1075 	addrconf_dad_start(ift);
1076 	in6_ifa_put(ift);
1077 	in6_dev_put(idev);
1078 out:
1079 	return ret;
1080 }
1081 #endif
1082 
1083 /*
1084  *	Choose an appropriate source address (RFC3484)
1085  */
1086 enum {
1087 	IPV6_SADDR_RULE_INIT = 0,
1088 	IPV6_SADDR_RULE_LOCAL,
1089 	IPV6_SADDR_RULE_SCOPE,
1090 	IPV6_SADDR_RULE_PREFERRED,
1091 #ifdef CONFIG_IPV6_MIP6
1092 	IPV6_SADDR_RULE_HOA,
1093 #endif
1094 	IPV6_SADDR_RULE_OIF,
1095 	IPV6_SADDR_RULE_LABEL,
1096 #ifdef CONFIG_IPV6_PRIVACY
1097 	IPV6_SADDR_RULE_PRIVACY,
1098 #endif
1099 	IPV6_SADDR_RULE_ORCHID,
1100 	IPV6_SADDR_RULE_PREFIX,
1101 	IPV6_SADDR_RULE_MAX
1102 };
1103 
1104 struct ipv6_saddr_score {
1105 	int			rule;
1106 	int			addr_type;
1107 	struct inet6_ifaddr	*ifa;
1108 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1109 	int			scopedist;
1110 	int			matchlen;
1111 };
1112 
1113 struct ipv6_saddr_dst {
1114 	const struct in6_addr *addr;
1115 	int ifindex;
1116 	int scope;
1117 	int label;
1118 	unsigned int prefs;
1119 };
1120 
1121 static inline int ipv6_saddr_preferred(int type)
1122 {
1123 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1124 		return 1;
1125 	return 0;
1126 }
1127 
1128 static int ipv6_get_saddr_eval(struct net *net,
1129 			       struct ipv6_saddr_score *score,
1130 			       struct ipv6_saddr_dst *dst,
1131 			       int i)
1132 {
1133 	int ret;
1134 
1135 	if (i <= score->rule) {
1136 		switch (i) {
1137 		case IPV6_SADDR_RULE_SCOPE:
1138 			ret = score->scopedist;
1139 			break;
1140 		case IPV6_SADDR_RULE_PREFIX:
1141 			ret = score->matchlen;
1142 			break;
1143 		default:
1144 			ret = !!test_bit(i, score->scorebits);
1145 		}
1146 		goto out;
1147 	}
1148 
1149 	switch (i) {
1150 	case IPV6_SADDR_RULE_INIT:
1151 		/* Rule 0: remember if hiscore is not ready yet */
1152 		ret = !!score->ifa;
1153 		break;
1154 	case IPV6_SADDR_RULE_LOCAL:
1155 		/* Rule 1: Prefer same address */
1156 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1157 		break;
1158 	case IPV6_SADDR_RULE_SCOPE:
1159 		/* Rule 2: Prefer appropriate scope
1160 		 *
1161 		 *      ret
1162 		 *       ^
1163 		 *    -1 |  d 15
1164 		 *    ---+--+-+---> scope
1165 		 *       |
1166 		 *       |             d is scope of the destination.
1167 		 *  B-d  |  \
1168 		 *       |   \      <- smaller scope is better if
1169 		 *  B-15 |    \        if scope is enough for destinaion.
1170 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1171 		 * d-C-1 | /
1172 		 *       |/         <- greater is better
1173 		 *   -C  /             if scope is not enough for destination.
1174 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1175 		 *
1176 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1177 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1178 		 * Assume B = 0 and we get C > 29.
1179 		 */
1180 		ret = __ipv6_addr_src_scope(score->addr_type);
1181 		if (ret >= dst->scope)
1182 			ret = -ret;
1183 		else
1184 			ret -= 128;	/* 30 is enough */
1185 		score->scopedist = ret;
1186 		break;
1187 	case IPV6_SADDR_RULE_PREFERRED:
1188 		/* Rule 3: Avoid deprecated and optimistic addresses */
1189 		ret = ipv6_saddr_preferred(score->addr_type) ||
1190 		      !(score->ifa->flags & (IFA_F_DEPRECATED|IFA_F_OPTIMISTIC));
1191 		break;
1192 #ifdef CONFIG_IPV6_MIP6
1193 	case IPV6_SADDR_RULE_HOA:
1194 	    {
1195 		/* Rule 4: Prefer home address */
1196 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1197 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1198 		break;
1199 	    }
1200 #endif
1201 	case IPV6_SADDR_RULE_OIF:
1202 		/* Rule 5: Prefer outgoing interface */
1203 		ret = (!dst->ifindex ||
1204 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1205 		break;
1206 	case IPV6_SADDR_RULE_LABEL:
1207 		/* Rule 6: Prefer matching label */
1208 		ret = ipv6_addr_label(net,
1209 				      &score->ifa->addr, score->addr_type,
1210 				      score->ifa->idev->dev->ifindex) == dst->label;
1211 		break;
1212 #ifdef CONFIG_IPV6_PRIVACY
1213 	case IPV6_SADDR_RULE_PRIVACY:
1214 	    {
1215 		/* Rule 7: Prefer public address
1216 		 * Note: prefer temporary address if use_tempaddr >= 2
1217 		 */
1218 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1219 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1220 				score->ifa->idev->cnf.use_tempaddr >= 2;
1221 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1222 		break;
1223 	    }
1224 #endif
1225 	case IPV6_SADDR_RULE_ORCHID:
1226 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1227 		 *	    non-ORCHID vs non-ORCHID
1228 		 */
1229 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1230 			ipv6_addr_orchid(dst->addr));
1231 		break;
1232 	case IPV6_SADDR_RULE_PREFIX:
1233 		/* Rule 8: Use longest matching prefix */
1234 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1235 		if (ret > score->ifa->prefix_len)
1236 			ret = score->ifa->prefix_len;
1237 		score->matchlen = ret;
1238 		break;
1239 	default:
1240 		ret = 0;
1241 	}
1242 
1243 	if (ret)
1244 		__set_bit(i, score->scorebits);
1245 	score->rule = i;
1246 out:
1247 	return ret;
1248 }
1249 
1250 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1251 		       const struct in6_addr *daddr, unsigned int prefs,
1252 		       struct in6_addr *saddr)
1253 {
1254 	struct ipv6_saddr_score scores[2],
1255 				*score = &scores[0], *hiscore = &scores[1];
1256 	struct ipv6_saddr_dst dst;
1257 	struct net_device *dev;
1258 	int dst_type;
1259 
1260 	dst_type = __ipv6_addr_type(daddr);
1261 	dst.addr = daddr;
1262 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1263 	dst.scope = __ipv6_addr_src_scope(dst_type);
1264 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1265 	dst.prefs = prefs;
1266 
1267 	hiscore->rule = -1;
1268 	hiscore->ifa = NULL;
1269 
1270 	rcu_read_lock();
1271 
1272 	for_each_netdev_rcu(net, dev) {
1273 		struct inet6_dev *idev;
1274 
1275 		/* Candidate Source Address (section 4)
1276 		 *  - multicast and link-local destination address,
1277 		 *    the set of candidate source address MUST only
1278 		 *    include addresses assigned to interfaces
1279 		 *    belonging to the same link as the outgoing
1280 		 *    interface.
1281 		 * (- For site-local destination addresses, the
1282 		 *    set of candidate source addresses MUST only
1283 		 *    include addresses assigned to interfaces
1284 		 *    belonging to the same site as the outgoing
1285 		 *    interface.)
1286 		 */
1287 		if (((dst_type & IPV6_ADDR_MULTICAST) ||
1288 		     dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) &&
1289 		    dst.ifindex && dev->ifindex != dst.ifindex)
1290 			continue;
1291 
1292 		idev = __in6_dev_get(dev);
1293 		if (!idev)
1294 			continue;
1295 
1296 		read_lock_bh(&idev->lock);
1297 		list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1298 			int i;
1299 
1300 			/*
1301 			 * - Tentative Address (RFC2462 section 5.4)
1302 			 *  - A tentative address is not considered
1303 			 *    "assigned to an interface" in the traditional
1304 			 *    sense, unless it is also flagged as optimistic.
1305 			 * - Candidate Source Address (section 4)
1306 			 *  - In any case, anycast addresses, multicast
1307 			 *    addresses, and the unspecified address MUST
1308 			 *    NOT be included in a candidate set.
1309 			 */
1310 			if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1311 			    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1312 				continue;
1313 
1314 			score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1315 
1316 			if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1317 				     score->addr_type & IPV6_ADDR_MULTICAST)) {
1318 				LIMIT_NETDEBUG(KERN_DEBUG
1319 					       "ADDRCONF: unspecified / multicast address "
1320 					       "assigned as unicast address on %s",
1321 					       dev->name);
1322 				continue;
1323 			}
1324 
1325 			score->rule = -1;
1326 			bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1327 
1328 			for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1329 				int minihiscore, miniscore;
1330 
1331 				minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
1332 				miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
1333 
1334 				if (minihiscore > miniscore) {
1335 					if (i == IPV6_SADDR_RULE_SCOPE &&
1336 					    score->scopedist > 0) {
1337 						/*
1338 						 * special case:
1339 						 * each remaining entry
1340 						 * has too small (not enough)
1341 						 * scope, because ifa entries
1342 						 * are sorted by their scope
1343 						 * values.
1344 						 */
1345 						goto try_nextdev;
1346 					}
1347 					break;
1348 				} else if (minihiscore < miniscore) {
1349 					if (hiscore->ifa)
1350 						in6_ifa_put(hiscore->ifa);
1351 
1352 					in6_ifa_hold(score->ifa);
1353 
1354 					swap(hiscore, score);
1355 
1356 					/* restore our iterator */
1357 					score->ifa = hiscore->ifa;
1358 
1359 					break;
1360 				}
1361 			}
1362 		}
1363 try_nextdev:
1364 		read_unlock_bh(&idev->lock);
1365 	}
1366 	rcu_read_unlock();
1367 
1368 	if (!hiscore->ifa)
1369 		return -EADDRNOTAVAIL;
1370 
1371 	*saddr = hiscore->ifa->addr;
1372 	in6_ifa_put(hiscore->ifa);
1373 	return 0;
1374 }
1375 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1376 
1377 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1378 		    unsigned char banned_flags)
1379 {
1380 	struct inet6_dev *idev;
1381 	int err = -EADDRNOTAVAIL;
1382 
1383 	rcu_read_lock();
1384 	idev = __in6_dev_get(dev);
1385 	if (idev) {
1386 		struct inet6_ifaddr *ifp;
1387 
1388 		read_lock_bh(&idev->lock);
1389 		list_for_each_entry(ifp, &idev->addr_list, if_list) {
1390 			if (ifp->scope == IFA_LINK &&
1391 			    !(ifp->flags & banned_flags)) {
1392 				*addr = ifp->addr;
1393 				err = 0;
1394 				break;
1395 			}
1396 		}
1397 		read_unlock_bh(&idev->lock);
1398 	}
1399 	rcu_read_unlock();
1400 	return err;
1401 }
1402 
1403 static int ipv6_count_addresses(struct inet6_dev *idev)
1404 {
1405 	int cnt = 0;
1406 	struct inet6_ifaddr *ifp;
1407 
1408 	read_lock_bh(&idev->lock);
1409 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1410 		cnt++;
1411 	read_unlock_bh(&idev->lock);
1412 	return cnt;
1413 }
1414 
1415 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1416 		  struct net_device *dev, int strict)
1417 {
1418 	struct inet6_ifaddr *ifp;
1419 	struct hlist_node *node;
1420 	unsigned int hash = inet6_addr_hash(addr);
1421 
1422 	rcu_read_lock_bh();
1423 	hlist_for_each_entry_rcu(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1424 		if (!net_eq(dev_net(ifp->idev->dev), net))
1425 			continue;
1426 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1427 		    !(ifp->flags&IFA_F_TENTATIVE) &&
1428 		    (dev == NULL || ifp->idev->dev == dev ||
1429 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1430 			rcu_read_unlock_bh();
1431 			return 1;
1432 		}
1433 	}
1434 
1435 	rcu_read_unlock_bh();
1436 	return 0;
1437 }
1438 EXPORT_SYMBOL(ipv6_chk_addr);
1439 
1440 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1441 			       struct net_device *dev)
1442 {
1443 	unsigned int hash = inet6_addr_hash(addr);
1444 	struct inet6_ifaddr *ifp;
1445 	struct hlist_node *node;
1446 
1447 	hlist_for_each_entry(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1448 		if (!net_eq(dev_net(ifp->idev->dev), net))
1449 			continue;
1450 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1451 			if (dev == NULL || ifp->idev->dev == dev)
1452 				return true;
1453 		}
1454 	}
1455 	return false;
1456 }
1457 
1458 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1459 {
1460 	struct inet6_dev *idev;
1461 	struct inet6_ifaddr *ifa;
1462 	int	onlink;
1463 
1464 	onlink = 0;
1465 	rcu_read_lock();
1466 	idev = __in6_dev_get(dev);
1467 	if (idev) {
1468 		read_lock_bh(&idev->lock);
1469 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1470 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1471 						   ifa->prefix_len);
1472 			if (onlink)
1473 				break;
1474 		}
1475 		read_unlock_bh(&idev->lock);
1476 	}
1477 	rcu_read_unlock();
1478 	return onlink;
1479 }
1480 EXPORT_SYMBOL(ipv6_chk_prefix);
1481 
1482 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1483 				     struct net_device *dev, int strict)
1484 {
1485 	struct inet6_ifaddr *ifp, *result = NULL;
1486 	unsigned int hash = inet6_addr_hash(addr);
1487 	struct hlist_node *node;
1488 
1489 	rcu_read_lock_bh();
1490 	hlist_for_each_entry_rcu_bh(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1491 		if (!net_eq(dev_net(ifp->idev->dev), net))
1492 			continue;
1493 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1494 			if (dev == NULL || ifp->idev->dev == dev ||
1495 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1496 				result = ifp;
1497 				in6_ifa_hold(ifp);
1498 				break;
1499 			}
1500 		}
1501 	}
1502 	rcu_read_unlock_bh();
1503 
1504 	return result;
1505 }
1506 
1507 /* Gets referenced address, destroys ifaddr */
1508 
1509 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1510 {
1511 	if (ifp->flags&IFA_F_PERMANENT) {
1512 		spin_lock_bh(&ifp->lock);
1513 		addrconf_del_timer(ifp);
1514 		ifp->flags |= IFA_F_TENTATIVE;
1515 		if (dad_failed)
1516 			ifp->flags |= IFA_F_DADFAILED;
1517 		spin_unlock_bh(&ifp->lock);
1518 		if (dad_failed)
1519 			ipv6_ifa_notify(0, ifp);
1520 		in6_ifa_put(ifp);
1521 #ifdef CONFIG_IPV6_PRIVACY
1522 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1523 		struct inet6_ifaddr *ifpub;
1524 		spin_lock_bh(&ifp->lock);
1525 		ifpub = ifp->ifpub;
1526 		if (ifpub) {
1527 			in6_ifa_hold(ifpub);
1528 			spin_unlock_bh(&ifp->lock);
1529 			ipv6_create_tempaddr(ifpub, ifp);
1530 			in6_ifa_put(ifpub);
1531 		} else {
1532 			spin_unlock_bh(&ifp->lock);
1533 		}
1534 		ipv6_del_addr(ifp);
1535 #endif
1536 	} else
1537 		ipv6_del_addr(ifp);
1538 }
1539 
1540 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1541 {
1542 	int err = -ENOENT;
1543 
1544 	spin_lock(&ifp->state_lock);
1545 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1546 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1547 		err = 0;
1548 	}
1549 	spin_unlock(&ifp->state_lock);
1550 
1551 	return err;
1552 }
1553 
1554 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1555 {
1556 	struct inet6_dev *idev = ifp->idev;
1557 
1558 	if (addrconf_dad_end(ifp)) {
1559 		in6_ifa_put(ifp);
1560 		return;
1561 	}
1562 
1563 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1564 			     ifp->idev->dev->name, &ifp->addr);
1565 
1566 	if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1567 		struct in6_addr addr;
1568 
1569 		addr.s6_addr32[0] = htonl(0xfe800000);
1570 		addr.s6_addr32[1] = 0;
1571 
1572 		if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1573 		    ipv6_addr_equal(&ifp->addr, &addr)) {
1574 			/* DAD failed for link-local based on MAC address */
1575 			idev->cnf.disable_ipv6 = 1;
1576 
1577 			pr_info("%s: IPv6 being disabled!\n",
1578 				ifp->idev->dev->name);
1579 		}
1580 	}
1581 
1582 	addrconf_dad_stop(ifp, 1);
1583 }
1584 
1585 /* Join to solicited addr multicast group. */
1586 
1587 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
1588 {
1589 	struct in6_addr maddr;
1590 
1591 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1592 		return;
1593 
1594 	addrconf_addr_solict_mult(addr, &maddr);
1595 	ipv6_dev_mc_inc(dev, &maddr);
1596 }
1597 
1598 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
1599 {
1600 	struct in6_addr maddr;
1601 
1602 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1603 		return;
1604 
1605 	addrconf_addr_solict_mult(addr, &maddr);
1606 	__ipv6_dev_mc_dec(idev, &maddr);
1607 }
1608 
1609 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1610 {
1611 	struct in6_addr addr;
1612 	if (ifp->prefix_len == 127) /* RFC 6164 */
1613 		return;
1614 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1615 	if (ipv6_addr_any(&addr))
1616 		return;
1617 	ipv6_dev_ac_inc(ifp->idev->dev, &addr);
1618 }
1619 
1620 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1621 {
1622 	struct in6_addr addr;
1623 	if (ifp->prefix_len == 127) /* RFC 6164 */
1624 		return;
1625 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1626 	if (ipv6_addr_any(&addr))
1627 		return;
1628 	__ipv6_dev_ac_dec(ifp->idev, &addr);
1629 }
1630 
1631 static int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
1632 {
1633 	if (dev->addr_len != ETH_ALEN)
1634 		return -1;
1635 	memcpy(eui, dev->dev_addr, 3);
1636 	memcpy(eui + 5, dev->dev_addr + 3, 3);
1637 
1638 	/*
1639 	 * The zSeries OSA network cards can be shared among various
1640 	 * OS instances, but the OSA cards have only one MAC address.
1641 	 * This leads to duplicate address conflicts in conjunction
1642 	 * with IPv6 if more than one instance uses the same card.
1643 	 *
1644 	 * The driver for these cards can deliver a unique 16-bit
1645 	 * identifier for each instance sharing the same card.  It is
1646 	 * placed instead of 0xFFFE in the interface identifier.  The
1647 	 * "u" bit of the interface identifier is not inverted in this
1648 	 * case.  Hence the resulting interface identifier has local
1649 	 * scope according to RFC2373.
1650 	 */
1651 	if (dev->dev_id) {
1652 		eui[3] = (dev->dev_id >> 8) & 0xFF;
1653 		eui[4] = dev->dev_id & 0xFF;
1654 	} else {
1655 		eui[3] = 0xFF;
1656 		eui[4] = 0xFE;
1657 		eui[0] ^= 2;
1658 	}
1659 	return 0;
1660 }
1661 
1662 static int addrconf_ifid_eui64(u8 *eui, struct net_device *dev)
1663 {
1664 	if (dev->addr_len != IEEE802154_ADDR_LEN)
1665 		return -1;
1666 	memcpy(eui, dev->dev_addr, 8);
1667 	return 0;
1668 }
1669 
1670 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
1671 {
1672 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
1673 	if (dev->addr_len != ARCNET_ALEN)
1674 		return -1;
1675 	memset(eui, 0, 7);
1676 	eui[7] = *(u8 *)dev->dev_addr;
1677 	return 0;
1678 }
1679 
1680 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
1681 {
1682 	if (dev->addr_len != INFINIBAND_ALEN)
1683 		return -1;
1684 	memcpy(eui, dev->dev_addr + 12, 8);
1685 	eui[0] |= 2;
1686 	return 0;
1687 }
1688 
1689 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
1690 {
1691 	if (addr == 0)
1692 		return -1;
1693 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
1694 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
1695 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
1696 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
1697 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
1698 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
1699 	eui[1] = 0;
1700 	eui[2] = 0x5E;
1701 	eui[3] = 0xFE;
1702 	memcpy(eui + 4, &addr, 4);
1703 	return 0;
1704 }
1705 
1706 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
1707 {
1708 	if (dev->priv_flags & IFF_ISATAP)
1709 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1710 	return -1;
1711 }
1712 
1713 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
1714 {
1715 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1716 }
1717 
1718 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
1719 {
1720 	switch (dev->type) {
1721 	case ARPHRD_ETHER:
1722 	case ARPHRD_FDDI:
1723 		return addrconf_ifid_eui48(eui, dev);
1724 	case ARPHRD_ARCNET:
1725 		return addrconf_ifid_arcnet(eui, dev);
1726 	case ARPHRD_INFINIBAND:
1727 		return addrconf_ifid_infiniband(eui, dev);
1728 	case ARPHRD_SIT:
1729 		return addrconf_ifid_sit(eui, dev);
1730 	case ARPHRD_IPGRE:
1731 		return addrconf_ifid_gre(eui, dev);
1732 	case ARPHRD_IEEE802154:
1733 		return addrconf_ifid_eui64(eui, dev);
1734 	}
1735 	return -1;
1736 }
1737 
1738 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
1739 {
1740 	int err = -1;
1741 	struct inet6_ifaddr *ifp;
1742 
1743 	read_lock_bh(&idev->lock);
1744 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
1745 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
1746 			memcpy(eui, ifp->addr.s6_addr+8, 8);
1747 			err = 0;
1748 			break;
1749 		}
1750 	}
1751 	read_unlock_bh(&idev->lock);
1752 	return err;
1753 }
1754 
1755 #ifdef CONFIG_IPV6_PRIVACY
1756 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
1757 static void __ipv6_regen_rndid(struct inet6_dev *idev)
1758 {
1759 regen:
1760 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
1761 	idev->rndid[0] &= ~0x02;
1762 
1763 	/*
1764 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
1765 	 * check if generated address is not inappropriate
1766 	 *
1767 	 *  - Reserved subnet anycast (RFC 2526)
1768 	 *	11111101 11....11 1xxxxxxx
1769 	 *  - ISATAP (RFC4214) 6.1
1770 	 *	00-00-5E-FE-xx-xx-xx-xx
1771 	 *  - value 0
1772 	 *  - XXX: already assigned to an address on the device
1773 	 */
1774 	if (idev->rndid[0] == 0xfd &&
1775 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
1776 	    (idev->rndid[7]&0x80))
1777 		goto regen;
1778 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
1779 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
1780 			goto regen;
1781 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
1782 			goto regen;
1783 	}
1784 }
1785 
1786 static void ipv6_regen_rndid(unsigned long data)
1787 {
1788 	struct inet6_dev *idev = (struct inet6_dev *) data;
1789 	unsigned long expires;
1790 
1791 	rcu_read_lock_bh();
1792 	write_lock_bh(&idev->lock);
1793 
1794 	if (idev->dead)
1795 		goto out;
1796 
1797 	__ipv6_regen_rndid(idev);
1798 
1799 	expires = jiffies +
1800 		idev->cnf.temp_prefered_lft * HZ -
1801 		idev->cnf.regen_max_retry * idev->cnf.dad_transmits * idev->nd_parms->retrans_time -
1802 		idev->cnf.max_desync_factor * HZ;
1803 	if (time_before(expires, jiffies)) {
1804 		pr_warn("%s: too short regeneration interval; timer disabled for %s\n",
1805 			__func__, idev->dev->name);
1806 		goto out;
1807 	}
1808 
1809 	if (!mod_timer(&idev->regen_timer, expires))
1810 		in6_dev_hold(idev);
1811 
1812 out:
1813 	write_unlock_bh(&idev->lock);
1814 	rcu_read_unlock_bh();
1815 	in6_dev_put(idev);
1816 }
1817 
1818 static void  __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
1819 {
1820 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
1821 		__ipv6_regen_rndid(idev);
1822 }
1823 #endif
1824 
1825 /*
1826  *	Add prefix route.
1827  */
1828 
1829 static void
1830 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
1831 		      unsigned long expires, u32 flags)
1832 {
1833 	struct fib6_config cfg = {
1834 		.fc_table = RT6_TABLE_PREFIX,
1835 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1836 		.fc_ifindex = dev->ifindex,
1837 		.fc_expires = expires,
1838 		.fc_dst_len = plen,
1839 		.fc_flags = RTF_UP | flags,
1840 		.fc_nlinfo.nl_net = dev_net(dev),
1841 		.fc_protocol = RTPROT_KERNEL,
1842 	};
1843 
1844 	cfg.fc_dst = *pfx;
1845 
1846 	/* Prevent useless cloning on PtP SIT.
1847 	   This thing is done here expecting that the whole
1848 	   class of non-broadcast devices need not cloning.
1849 	 */
1850 #if IS_ENABLED(CONFIG_IPV6_SIT)
1851 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
1852 		cfg.fc_flags |= RTF_NONEXTHOP;
1853 #endif
1854 
1855 	ip6_route_add(&cfg);
1856 }
1857 
1858 
1859 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
1860 						  int plen,
1861 						  const struct net_device *dev,
1862 						  u32 flags, u32 noflags)
1863 {
1864 	struct fib6_node *fn;
1865 	struct rt6_info *rt = NULL;
1866 	struct fib6_table *table;
1867 
1868 	table = fib6_get_table(dev_net(dev), RT6_TABLE_PREFIX);
1869 	if (table == NULL)
1870 		return NULL;
1871 
1872 	read_lock_bh(&table->tb6_lock);
1873 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
1874 	if (!fn)
1875 		goto out;
1876 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1877 		if (rt->dst.dev->ifindex != dev->ifindex)
1878 			continue;
1879 		if ((rt->rt6i_flags & flags) != flags)
1880 			continue;
1881 		if ((noflags != 0) && ((rt->rt6i_flags & flags) != 0))
1882 			continue;
1883 		dst_hold(&rt->dst);
1884 		break;
1885 	}
1886 out:
1887 	read_unlock_bh(&table->tb6_lock);
1888 	return rt;
1889 }
1890 
1891 
1892 /* Create "default" multicast route to the interface */
1893 
1894 static void addrconf_add_mroute(struct net_device *dev)
1895 {
1896 	struct fib6_config cfg = {
1897 		.fc_table = RT6_TABLE_LOCAL,
1898 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1899 		.fc_ifindex = dev->ifindex,
1900 		.fc_dst_len = 8,
1901 		.fc_flags = RTF_UP,
1902 		.fc_nlinfo.nl_net = dev_net(dev),
1903 	};
1904 
1905 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
1906 
1907 	ip6_route_add(&cfg);
1908 }
1909 
1910 #if IS_ENABLED(CONFIG_IPV6_SIT)
1911 static void sit_route_add(struct net_device *dev)
1912 {
1913 	struct fib6_config cfg = {
1914 		.fc_table = RT6_TABLE_MAIN,
1915 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1916 		.fc_ifindex = dev->ifindex,
1917 		.fc_dst_len = 96,
1918 		.fc_flags = RTF_UP | RTF_NONEXTHOP,
1919 		.fc_nlinfo.nl_net = dev_net(dev),
1920 	};
1921 
1922 	/* prefix length - 96 bits "::d.d.d.d" */
1923 	ip6_route_add(&cfg);
1924 }
1925 #endif
1926 
1927 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
1928 {
1929 	struct inet6_dev *idev;
1930 
1931 	ASSERT_RTNL();
1932 
1933 	idev = ipv6_find_idev(dev);
1934 	if (!idev)
1935 		return ERR_PTR(-ENOBUFS);
1936 
1937 	if (idev->cnf.disable_ipv6)
1938 		return ERR_PTR(-EACCES);
1939 
1940 	/* Add default multicast route */
1941 	if (!(dev->flags & IFF_LOOPBACK))
1942 		addrconf_add_mroute(dev);
1943 
1944 	return idev;
1945 }
1946 
1947 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
1948 {
1949 	struct prefix_info *pinfo;
1950 	__u32 valid_lft;
1951 	__u32 prefered_lft;
1952 	int addr_type;
1953 	struct inet6_dev *in6_dev;
1954 	struct net *net = dev_net(dev);
1955 
1956 	pinfo = (struct prefix_info *) opt;
1957 
1958 	if (len < sizeof(struct prefix_info)) {
1959 		ADBG(("addrconf: prefix option too short\n"));
1960 		return;
1961 	}
1962 
1963 	/*
1964 	 *	Validation checks ([ADDRCONF], page 19)
1965 	 */
1966 
1967 	addr_type = ipv6_addr_type(&pinfo->prefix);
1968 
1969 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
1970 		return;
1971 
1972 	valid_lft = ntohl(pinfo->valid);
1973 	prefered_lft = ntohl(pinfo->prefered);
1974 
1975 	if (prefered_lft > valid_lft) {
1976 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
1977 		return;
1978 	}
1979 
1980 	in6_dev = in6_dev_get(dev);
1981 
1982 	if (in6_dev == NULL) {
1983 		net_dbg_ratelimited("addrconf: device %s not configured\n",
1984 				    dev->name);
1985 		return;
1986 	}
1987 
1988 	/*
1989 	 *	Two things going on here:
1990 	 *	1) Add routes for on-link prefixes
1991 	 *	2) Configure prefixes with the auto flag set
1992 	 */
1993 
1994 	if (pinfo->onlink) {
1995 		struct rt6_info *rt;
1996 		unsigned long rt_expires;
1997 
1998 		/* Avoid arithmetic overflow. Really, we could
1999 		 * save rt_expires in seconds, likely valid_lft,
2000 		 * but it would require division in fib gc, that it
2001 		 * not good.
2002 		 */
2003 		if (HZ > USER_HZ)
2004 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2005 		else
2006 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2007 
2008 		if (addrconf_finite_timeout(rt_expires))
2009 			rt_expires *= HZ;
2010 
2011 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2012 					       pinfo->prefix_len,
2013 					       dev,
2014 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2015 					       RTF_GATEWAY | RTF_DEFAULT);
2016 
2017 		if (rt) {
2018 			/* Autoconf prefix route */
2019 			if (valid_lft == 0) {
2020 				ip6_del_rt(rt);
2021 				rt = NULL;
2022 			} else if (addrconf_finite_timeout(rt_expires)) {
2023 				/* not infinity */
2024 				rt6_set_expires(rt, jiffies + rt_expires);
2025 			} else {
2026 				rt6_clean_expires(rt);
2027 			}
2028 		} else if (valid_lft) {
2029 			clock_t expires = 0;
2030 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2031 			if (addrconf_finite_timeout(rt_expires)) {
2032 				/* not infinity */
2033 				flags |= RTF_EXPIRES;
2034 				expires = jiffies_to_clock_t(rt_expires);
2035 			}
2036 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2037 					      dev, expires, flags);
2038 		}
2039 		ip6_rt_put(rt);
2040 	}
2041 
2042 	/* Try to figure out our local address for this prefix */
2043 
2044 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2045 		struct inet6_ifaddr *ifp;
2046 		struct in6_addr addr;
2047 		int create = 0, update_lft = 0;
2048 
2049 		if (pinfo->prefix_len == 64) {
2050 			memcpy(&addr, &pinfo->prefix, 8);
2051 			if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2052 			    ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2053 				in6_dev_put(in6_dev);
2054 				return;
2055 			}
2056 			goto ok;
2057 		}
2058 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2059 				    pinfo->prefix_len);
2060 		in6_dev_put(in6_dev);
2061 		return;
2062 
2063 ok:
2064 
2065 		ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
2066 
2067 		if (ifp == NULL && valid_lft) {
2068 			int max_addresses = in6_dev->cnf.max_addresses;
2069 			u32 addr_flags = 0;
2070 
2071 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2072 			if (in6_dev->cnf.optimistic_dad &&
2073 			    !net->ipv6.devconf_all->forwarding && sllao)
2074 				addr_flags = IFA_F_OPTIMISTIC;
2075 #endif
2076 
2077 			/* Do not allow to create too much of autoconfigured
2078 			 * addresses; this would be too easy way to crash kernel.
2079 			 */
2080 			if (!max_addresses ||
2081 			    ipv6_count_addresses(in6_dev) < max_addresses)
2082 				ifp = ipv6_add_addr(in6_dev, &addr, pinfo->prefix_len,
2083 						    addr_type&IPV6_ADDR_SCOPE_MASK,
2084 						    addr_flags);
2085 
2086 			if (!ifp || IS_ERR(ifp)) {
2087 				in6_dev_put(in6_dev);
2088 				return;
2089 			}
2090 
2091 			update_lft = create = 1;
2092 			ifp->cstamp = jiffies;
2093 			addrconf_dad_start(ifp);
2094 		}
2095 
2096 		if (ifp) {
2097 			int flags;
2098 			unsigned long now;
2099 #ifdef CONFIG_IPV6_PRIVACY
2100 			struct inet6_ifaddr *ift;
2101 #endif
2102 			u32 stored_lft;
2103 
2104 			/* update lifetime (RFC2462 5.5.3 e) */
2105 			spin_lock(&ifp->lock);
2106 			now = jiffies;
2107 			if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2108 				stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2109 			else
2110 				stored_lft = 0;
2111 			if (!update_lft && stored_lft) {
2112 				if (valid_lft > MIN_VALID_LIFETIME ||
2113 				    valid_lft > stored_lft)
2114 					update_lft = 1;
2115 				else if (stored_lft <= MIN_VALID_LIFETIME) {
2116 					/* valid_lft <= stored_lft is always true */
2117 					/*
2118 					 * RFC 4862 Section 5.5.3e:
2119 					 * "Note that the preferred lifetime of
2120 					 *  the corresponding address is always
2121 					 *  reset to the Preferred Lifetime in
2122 					 *  the received Prefix Information
2123 					 *  option, regardless of whether the
2124 					 *  valid lifetime is also reset or
2125 					 *  ignored."
2126 					 *
2127 					 *  So if the preferred lifetime in
2128 					 *  this advertisement is different
2129 					 *  than what we have stored, but the
2130 					 *  valid lifetime is invalid, just
2131 					 *  reset prefered_lft.
2132 					 *
2133 					 *  We must set the valid lifetime
2134 					 *  to the stored lifetime since we'll
2135 					 *  be updating the timestamp below,
2136 					 *  else we'll set it back to the
2137 					 *  minimum.
2138 					 */
2139 					if (prefered_lft != ifp->prefered_lft) {
2140 						valid_lft = stored_lft;
2141 						update_lft = 1;
2142 					}
2143 				} else {
2144 					valid_lft = MIN_VALID_LIFETIME;
2145 					if (valid_lft < prefered_lft)
2146 						prefered_lft = valid_lft;
2147 					update_lft = 1;
2148 				}
2149 			}
2150 
2151 			if (update_lft) {
2152 				ifp->valid_lft = valid_lft;
2153 				ifp->prefered_lft = prefered_lft;
2154 				ifp->tstamp = now;
2155 				flags = ifp->flags;
2156 				ifp->flags &= ~IFA_F_DEPRECATED;
2157 				spin_unlock(&ifp->lock);
2158 
2159 				if (!(flags&IFA_F_TENTATIVE))
2160 					ipv6_ifa_notify(0, ifp);
2161 			} else
2162 				spin_unlock(&ifp->lock);
2163 
2164 #ifdef CONFIG_IPV6_PRIVACY
2165 			read_lock_bh(&in6_dev->lock);
2166 			/* update all temporary addresses in the list */
2167 			list_for_each_entry(ift, &in6_dev->tempaddr_list,
2168 					    tmp_list) {
2169 				int age, max_valid, max_prefered;
2170 
2171 				if (ifp != ift->ifpub)
2172 					continue;
2173 
2174 				/*
2175 				 * RFC 4941 section 3.3:
2176 				 * If a received option will extend the lifetime
2177 				 * of a public address, the lifetimes of
2178 				 * temporary addresses should be extended,
2179 				 * subject to the overall constraint that no
2180 				 * temporary addresses should ever remain
2181 				 * "valid" or "preferred" for a time longer than
2182 				 * (TEMP_VALID_LIFETIME) or
2183 				 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR),
2184 				 * respectively.
2185 				 */
2186 				age = (now - ift->cstamp) / HZ;
2187 				max_valid = in6_dev->cnf.temp_valid_lft - age;
2188 				if (max_valid < 0)
2189 					max_valid = 0;
2190 
2191 				max_prefered = in6_dev->cnf.temp_prefered_lft -
2192 					       in6_dev->cnf.max_desync_factor -
2193 					       age;
2194 				if (max_prefered < 0)
2195 					max_prefered = 0;
2196 
2197 				if (valid_lft > max_valid)
2198 					valid_lft = max_valid;
2199 
2200 				if (prefered_lft > max_prefered)
2201 					prefered_lft = max_prefered;
2202 
2203 				spin_lock(&ift->lock);
2204 				flags = ift->flags;
2205 				ift->valid_lft = valid_lft;
2206 				ift->prefered_lft = prefered_lft;
2207 				ift->tstamp = now;
2208 				if (prefered_lft > 0)
2209 					ift->flags &= ~IFA_F_DEPRECATED;
2210 
2211 				spin_unlock(&ift->lock);
2212 				if (!(flags&IFA_F_TENTATIVE))
2213 					ipv6_ifa_notify(0, ift);
2214 			}
2215 
2216 			if ((create || list_empty(&in6_dev->tempaddr_list)) && in6_dev->cnf.use_tempaddr > 0) {
2217 				/*
2218 				 * When a new public address is created as
2219 				 * described in [ADDRCONF], also create a new
2220 				 * temporary address. Also create a temporary
2221 				 * address if it's enabled but no temporary
2222 				 * address currently exists.
2223 				 */
2224 				read_unlock_bh(&in6_dev->lock);
2225 				ipv6_create_tempaddr(ifp, NULL);
2226 			} else {
2227 				read_unlock_bh(&in6_dev->lock);
2228 			}
2229 #endif
2230 			in6_ifa_put(ifp);
2231 			addrconf_verify(0);
2232 		}
2233 	}
2234 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2235 	in6_dev_put(in6_dev);
2236 }
2237 
2238 /*
2239  *	Set destination address.
2240  *	Special case for SIT interfaces where we create a new "virtual"
2241  *	device.
2242  */
2243 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2244 {
2245 	struct in6_ifreq ireq;
2246 	struct net_device *dev;
2247 	int err = -EINVAL;
2248 
2249 	rtnl_lock();
2250 
2251 	err = -EFAULT;
2252 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2253 		goto err_exit;
2254 
2255 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2256 
2257 	err = -ENODEV;
2258 	if (dev == NULL)
2259 		goto err_exit;
2260 
2261 #if IS_ENABLED(CONFIG_IPV6_SIT)
2262 	if (dev->type == ARPHRD_SIT) {
2263 		const struct net_device_ops *ops = dev->netdev_ops;
2264 		struct ifreq ifr;
2265 		struct ip_tunnel_parm p;
2266 
2267 		err = -EADDRNOTAVAIL;
2268 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2269 			goto err_exit;
2270 
2271 		memset(&p, 0, sizeof(p));
2272 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2273 		p.iph.saddr = 0;
2274 		p.iph.version = 4;
2275 		p.iph.ihl = 5;
2276 		p.iph.protocol = IPPROTO_IPV6;
2277 		p.iph.ttl = 64;
2278 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2279 
2280 		if (ops->ndo_do_ioctl) {
2281 			mm_segment_t oldfs = get_fs();
2282 
2283 			set_fs(KERNEL_DS);
2284 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2285 			set_fs(oldfs);
2286 		} else
2287 			err = -EOPNOTSUPP;
2288 
2289 		if (err == 0) {
2290 			err = -ENOBUFS;
2291 			dev = __dev_get_by_name(net, p.name);
2292 			if (!dev)
2293 				goto err_exit;
2294 			err = dev_open(dev);
2295 		}
2296 	}
2297 #endif
2298 
2299 err_exit:
2300 	rtnl_unlock();
2301 	return err;
2302 }
2303 
2304 /*
2305  *	Manual configuration of address on an interface
2306  */
2307 static int inet6_addr_add(struct net *net, int ifindex, const struct in6_addr *pfx,
2308 			  unsigned int plen, __u8 ifa_flags, __u32 prefered_lft,
2309 			  __u32 valid_lft)
2310 {
2311 	struct inet6_ifaddr *ifp;
2312 	struct inet6_dev *idev;
2313 	struct net_device *dev;
2314 	int scope;
2315 	u32 flags;
2316 	clock_t expires;
2317 	unsigned long timeout;
2318 
2319 	ASSERT_RTNL();
2320 
2321 	if (plen > 128)
2322 		return -EINVAL;
2323 
2324 	/* check the lifetime */
2325 	if (!valid_lft || prefered_lft > valid_lft)
2326 		return -EINVAL;
2327 
2328 	dev = __dev_get_by_index(net, ifindex);
2329 	if (!dev)
2330 		return -ENODEV;
2331 
2332 	idev = addrconf_add_dev(dev);
2333 	if (IS_ERR(idev))
2334 		return PTR_ERR(idev);
2335 
2336 	scope = ipv6_addr_scope(pfx);
2337 
2338 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2339 	if (addrconf_finite_timeout(timeout)) {
2340 		expires = jiffies_to_clock_t(timeout * HZ);
2341 		valid_lft = timeout;
2342 		flags = RTF_EXPIRES;
2343 	} else {
2344 		expires = 0;
2345 		flags = 0;
2346 		ifa_flags |= IFA_F_PERMANENT;
2347 	}
2348 
2349 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2350 	if (addrconf_finite_timeout(timeout)) {
2351 		if (timeout == 0)
2352 			ifa_flags |= IFA_F_DEPRECATED;
2353 		prefered_lft = timeout;
2354 	}
2355 
2356 	ifp = ipv6_add_addr(idev, pfx, plen, scope, ifa_flags);
2357 
2358 	if (!IS_ERR(ifp)) {
2359 		spin_lock_bh(&ifp->lock);
2360 		ifp->valid_lft = valid_lft;
2361 		ifp->prefered_lft = prefered_lft;
2362 		ifp->tstamp = jiffies;
2363 		spin_unlock_bh(&ifp->lock);
2364 
2365 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2366 				      expires, flags);
2367 		/*
2368 		 * Note that section 3.1 of RFC 4429 indicates
2369 		 * that the Optimistic flag should not be set for
2370 		 * manually configured addresses
2371 		 */
2372 		addrconf_dad_start(ifp);
2373 		in6_ifa_put(ifp);
2374 		addrconf_verify(0);
2375 		return 0;
2376 	}
2377 
2378 	return PTR_ERR(ifp);
2379 }
2380 
2381 static int inet6_addr_del(struct net *net, int ifindex, const struct in6_addr *pfx,
2382 			  unsigned int plen)
2383 {
2384 	struct inet6_ifaddr *ifp;
2385 	struct inet6_dev *idev;
2386 	struct net_device *dev;
2387 
2388 	if (plen > 128)
2389 		return -EINVAL;
2390 
2391 	dev = __dev_get_by_index(net, ifindex);
2392 	if (!dev)
2393 		return -ENODEV;
2394 
2395 	if ((idev = __in6_dev_get(dev)) == NULL)
2396 		return -ENXIO;
2397 
2398 	read_lock_bh(&idev->lock);
2399 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2400 		if (ifp->prefix_len == plen &&
2401 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2402 			in6_ifa_hold(ifp);
2403 			read_unlock_bh(&idev->lock);
2404 
2405 			ipv6_del_addr(ifp);
2406 
2407 			/* If the last address is deleted administratively,
2408 			   disable IPv6 on this interface.
2409 			 */
2410 			if (list_empty(&idev->addr_list))
2411 				addrconf_ifdown(idev->dev, 1);
2412 			return 0;
2413 		}
2414 	}
2415 	read_unlock_bh(&idev->lock);
2416 	return -EADDRNOTAVAIL;
2417 }
2418 
2419 
2420 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2421 {
2422 	struct in6_ifreq ireq;
2423 	int err;
2424 
2425 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2426 		return -EPERM;
2427 
2428 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2429 		return -EFAULT;
2430 
2431 	rtnl_lock();
2432 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2433 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2434 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2435 	rtnl_unlock();
2436 	return err;
2437 }
2438 
2439 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2440 {
2441 	struct in6_ifreq ireq;
2442 	int err;
2443 
2444 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2445 		return -EPERM;
2446 
2447 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2448 		return -EFAULT;
2449 
2450 	rtnl_lock();
2451 	err = inet6_addr_del(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2452 			     ireq.ifr6_prefixlen);
2453 	rtnl_unlock();
2454 	return err;
2455 }
2456 
2457 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2458 		     int plen, int scope)
2459 {
2460 	struct inet6_ifaddr *ifp;
2461 
2462 	ifp = ipv6_add_addr(idev, addr, plen, scope, IFA_F_PERMANENT);
2463 	if (!IS_ERR(ifp)) {
2464 		spin_lock_bh(&ifp->lock);
2465 		ifp->flags &= ~IFA_F_TENTATIVE;
2466 		spin_unlock_bh(&ifp->lock);
2467 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2468 		in6_ifa_put(ifp);
2469 	}
2470 }
2471 
2472 #if IS_ENABLED(CONFIG_IPV6_SIT)
2473 static void sit_add_v4_addrs(struct inet6_dev *idev)
2474 {
2475 	struct in6_addr addr;
2476 	struct net_device *dev;
2477 	struct net *net = dev_net(idev->dev);
2478 	int scope;
2479 
2480 	ASSERT_RTNL();
2481 
2482 	memset(&addr, 0, sizeof(struct in6_addr));
2483 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2484 
2485 	if (idev->dev->flags&IFF_POINTOPOINT) {
2486 		addr.s6_addr32[0] = htonl(0xfe800000);
2487 		scope = IFA_LINK;
2488 	} else {
2489 		scope = IPV6_ADDR_COMPATv4;
2490 	}
2491 
2492 	if (addr.s6_addr32[3]) {
2493 		add_addr(idev, &addr, 128, scope);
2494 		return;
2495 	}
2496 
2497 	for_each_netdev(net, dev) {
2498 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
2499 		if (in_dev && (dev->flags & IFF_UP)) {
2500 			struct in_ifaddr *ifa;
2501 
2502 			int flag = scope;
2503 
2504 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2505 				int plen;
2506 
2507 				addr.s6_addr32[3] = ifa->ifa_local;
2508 
2509 				if (ifa->ifa_scope == RT_SCOPE_LINK)
2510 					continue;
2511 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2512 					if (idev->dev->flags&IFF_POINTOPOINT)
2513 						continue;
2514 					flag |= IFA_HOST;
2515 				}
2516 				if (idev->dev->flags&IFF_POINTOPOINT)
2517 					plen = 64;
2518 				else
2519 					plen = 96;
2520 
2521 				add_addr(idev, &addr, plen, flag);
2522 			}
2523 		}
2524 	}
2525 }
2526 #endif
2527 
2528 static void init_loopback(struct net_device *dev)
2529 {
2530 	struct inet6_dev  *idev;
2531 
2532 	/* ::1 */
2533 
2534 	ASSERT_RTNL();
2535 
2536 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2537 		pr_debug("%s: add_dev failed\n", __func__);
2538 		return;
2539 	}
2540 
2541 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2542 }
2543 
2544 static void addrconf_add_linklocal(struct inet6_dev *idev, const struct in6_addr *addr)
2545 {
2546 	struct inet6_ifaddr *ifp;
2547 	u32 addr_flags = IFA_F_PERMANENT;
2548 
2549 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2550 	if (idev->cnf.optimistic_dad &&
2551 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
2552 		addr_flags |= IFA_F_OPTIMISTIC;
2553 #endif
2554 
2555 
2556 	ifp = ipv6_add_addr(idev, addr, 64, IFA_LINK, addr_flags);
2557 	if (!IS_ERR(ifp)) {
2558 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
2559 		addrconf_dad_start(ifp);
2560 		in6_ifa_put(ifp);
2561 	}
2562 }
2563 
2564 static void addrconf_dev_config(struct net_device *dev)
2565 {
2566 	struct in6_addr addr;
2567 	struct inet6_dev *idev;
2568 
2569 	ASSERT_RTNL();
2570 
2571 	if ((dev->type != ARPHRD_ETHER) &&
2572 	    (dev->type != ARPHRD_FDDI) &&
2573 	    (dev->type != ARPHRD_ARCNET) &&
2574 	    (dev->type != ARPHRD_INFINIBAND) &&
2575 	    (dev->type != ARPHRD_IEEE802154)) {
2576 		/* Alas, we support only Ethernet autoconfiguration. */
2577 		return;
2578 	}
2579 
2580 	idev = addrconf_add_dev(dev);
2581 	if (IS_ERR(idev))
2582 		return;
2583 
2584 	memset(&addr, 0, sizeof(struct in6_addr));
2585 	addr.s6_addr32[0] = htonl(0xFE800000);
2586 
2587 	if (ipv6_generate_eui64(addr.s6_addr + 8, dev) == 0)
2588 		addrconf_add_linklocal(idev, &addr);
2589 }
2590 
2591 #if IS_ENABLED(CONFIG_IPV6_SIT)
2592 static void addrconf_sit_config(struct net_device *dev)
2593 {
2594 	struct inet6_dev *idev;
2595 
2596 	ASSERT_RTNL();
2597 
2598 	/*
2599 	 * Configure the tunnel with one of our IPv4
2600 	 * addresses... we should configure all of
2601 	 * our v4 addrs in the tunnel
2602 	 */
2603 
2604 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2605 		pr_debug("%s: add_dev failed\n", __func__);
2606 		return;
2607 	}
2608 
2609 	if (dev->priv_flags & IFF_ISATAP) {
2610 		struct in6_addr addr;
2611 
2612 		ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2613 		addrconf_prefix_route(&addr, 64, dev, 0, 0);
2614 		if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2615 			addrconf_add_linklocal(idev, &addr);
2616 		return;
2617 	}
2618 
2619 	sit_add_v4_addrs(idev);
2620 
2621 	if (dev->flags&IFF_POINTOPOINT)
2622 		addrconf_add_mroute(dev);
2623 	else
2624 		sit_route_add(dev);
2625 }
2626 #endif
2627 
2628 #if IS_ENABLED(CONFIG_NET_IPGRE)
2629 static void addrconf_gre_config(struct net_device *dev)
2630 {
2631 	struct inet6_dev *idev;
2632 	struct in6_addr addr;
2633 
2634 	pr_info("%s(%s)\n", __func__, dev->name);
2635 
2636 	ASSERT_RTNL();
2637 
2638 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2639 		pr_debug("%s: add_dev failed\n", __func__);
2640 		return;
2641 	}
2642 
2643 	ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2644 	addrconf_prefix_route(&addr, 64, dev, 0, 0);
2645 
2646 	if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2647 		addrconf_add_linklocal(idev, &addr);
2648 }
2649 #endif
2650 
2651 static inline int
2652 ipv6_inherit_linklocal(struct inet6_dev *idev, struct net_device *link_dev)
2653 {
2654 	struct in6_addr lladdr;
2655 
2656 	if (!ipv6_get_lladdr(link_dev, &lladdr, IFA_F_TENTATIVE)) {
2657 		addrconf_add_linklocal(idev, &lladdr);
2658 		return 0;
2659 	}
2660 	return -1;
2661 }
2662 
2663 static void ip6_tnl_add_linklocal(struct inet6_dev *idev)
2664 {
2665 	struct net_device *link_dev;
2666 	struct net *net = dev_net(idev->dev);
2667 
2668 	/* first try to inherit the link-local address from the link device */
2669 	if (idev->dev->iflink &&
2670 	    (link_dev = __dev_get_by_index(net, idev->dev->iflink))) {
2671 		if (!ipv6_inherit_linklocal(idev, link_dev))
2672 			return;
2673 	}
2674 	/* then try to inherit it from any device */
2675 	for_each_netdev(net, link_dev) {
2676 		if (!ipv6_inherit_linklocal(idev, link_dev))
2677 			return;
2678 	}
2679 	pr_debug("init ip6-ip6: add_linklocal failed\n");
2680 }
2681 
2682 /*
2683  * Autoconfigure tunnel with a link-local address so routing protocols,
2684  * DHCPv6, MLD etc. can be run over the virtual link
2685  */
2686 
2687 static void addrconf_ip6_tnl_config(struct net_device *dev)
2688 {
2689 	struct inet6_dev *idev;
2690 
2691 	ASSERT_RTNL();
2692 
2693 	idev = addrconf_add_dev(dev);
2694 	if (IS_ERR(idev)) {
2695 		pr_debug("init ip6-ip6: add_dev failed\n");
2696 		return;
2697 	}
2698 	ip6_tnl_add_linklocal(idev);
2699 }
2700 
2701 static int addrconf_notify(struct notifier_block *this, unsigned long event,
2702 			   void *data)
2703 {
2704 	struct net_device *dev = (struct net_device *) data;
2705 	struct inet6_dev *idev = __in6_dev_get(dev);
2706 	int run_pending = 0;
2707 	int err;
2708 
2709 	switch (event) {
2710 	case NETDEV_REGISTER:
2711 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2712 			idev = ipv6_add_dev(dev);
2713 			if (!idev)
2714 				return notifier_from_errno(-ENOMEM);
2715 		}
2716 		break;
2717 
2718 	case NETDEV_UP:
2719 	case NETDEV_CHANGE:
2720 		if (dev->flags & IFF_SLAVE)
2721 			break;
2722 
2723 		if (event == NETDEV_UP) {
2724 			if (!addrconf_qdisc_ok(dev)) {
2725 				/* device is not ready yet. */
2726 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
2727 					dev->name);
2728 				break;
2729 			}
2730 
2731 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
2732 				idev = ipv6_add_dev(dev);
2733 
2734 			if (idev) {
2735 				idev->if_flags |= IF_READY;
2736 				run_pending = 1;
2737 			}
2738 		} else {
2739 			if (!addrconf_qdisc_ok(dev)) {
2740 				/* device is still not ready. */
2741 				break;
2742 			}
2743 
2744 			if (idev) {
2745 				if (idev->if_flags & IF_READY)
2746 					/* device is already configured. */
2747 					break;
2748 				idev->if_flags |= IF_READY;
2749 			}
2750 
2751 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
2752 				dev->name);
2753 
2754 			run_pending = 1;
2755 		}
2756 
2757 		switch (dev->type) {
2758 #if IS_ENABLED(CONFIG_IPV6_SIT)
2759 		case ARPHRD_SIT:
2760 			addrconf_sit_config(dev);
2761 			break;
2762 #endif
2763 #if IS_ENABLED(CONFIG_NET_IPGRE)
2764 		case ARPHRD_IPGRE:
2765 			addrconf_gre_config(dev);
2766 			break;
2767 #endif
2768 		case ARPHRD_TUNNEL6:
2769 			addrconf_ip6_tnl_config(dev);
2770 			break;
2771 		case ARPHRD_LOOPBACK:
2772 			init_loopback(dev);
2773 			break;
2774 
2775 		default:
2776 			addrconf_dev_config(dev);
2777 			break;
2778 		}
2779 
2780 		if (idev) {
2781 			if (run_pending)
2782 				addrconf_dad_run(idev);
2783 
2784 			/*
2785 			 * If the MTU changed during the interface down,
2786 			 * when the interface up, the changed MTU must be
2787 			 * reflected in the idev as well as routers.
2788 			 */
2789 			if (idev->cnf.mtu6 != dev->mtu &&
2790 			    dev->mtu >= IPV6_MIN_MTU) {
2791 				rt6_mtu_change(dev, dev->mtu);
2792 				idev->cnf.mtu6 = dev->mtu;
2793 			}
2794 			idev->tstamp = jiffies;
2795 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
2796 
2797 			/*
2798 			 * If the changed mtu during down is lower than
2799 			 * IPV6_MIN_MTU stop IPv6 on this interface.
2800 			 */
2801 			if (dev->mtu < IPV6_MIN_MTU)
2802 				addrconf_ifdown(dev, 1);
2803 		}
2804 		break;
2805 
2806 	case NETDEV_CHANGEMTU:
2807 		if (idev && dev->mtu >= IPV6_MIN_MTU) {
2808 			rt6_mtu_change(dev, dev->mtu);
2809 			idev->cnf.mtu6 = dev->mtu;
2810 			break;
2811 		}
2812 
2813 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2814 			idev = ipv6_add_dev(dev);
2815 			if (idev)
2816 				break;
2817 		}
2818 
2819 		/*
2820 		 * MTU falled under IPV6_MIN_MTU.
2821 		 * Stop IPv6 on this interface.
2822 		 */
2823 
2824 	case NETDEV_DOWN:
2825 	case NETDEV_UNREGISTER:
2826 		/*
2827 		 *	Remove all addresses from this interface.
2828 		 */
2829 		addrconf_ifdown(dev, event != NETDEV_DOWN);
2830 		break;
2831 
2832 	case NETDEV_CHANGENAME:
2833 		if (idev) {
2834 			snmp6_unregister_dev(idev);
2835 			addrconf_sysctl_unregister(idev);
2836 			addrconf_sysctl_register(idev);
2837 			err = snmp6_register_dev(idev);
2838 			if (err)
2839 				return notifier_from_errno(err);
2840 		}
2841 		break;
2842 
2843 	case NETDEV_PRE_TYPE_CHANGE:
2844 	case NETDEV_POST_TYPE_CHANGE:
2845 		addrconf_type_change(dev, event);
2846 		break;
2847 	}
2848 
2849 	return NOTIFY_OK;
2850 }
2851 
2852 /*
2853  *	addrconf module should be notified of a device going up
2854  */
2855 static struct notifier_block ipv6_dev_notf = {
2856 	.notifier_call = addrconf_notify,
2857 };
2858 
2859 static void addrconf_type_change(struct net_device *dev, unsigned long event)
2860 {
2861 	struct inet6_dev *idev;
2862 	ASSERT_RTNL();
2863 
2864 	idev = __in6_dev_get(dev);
2865 
2866 	if (event == NETDEV_POST_TYPE_CHANGE)
2867 		ipv6_mc_remap(idev);
2868 	else if (event == NETDEV_PRE_TYPE_CHANGE)
2869 		ipv6_mc_unmap(idev);
2870 }
2871 
2872 static int addrconf_ifdown(struct net_device *dev, int how)
2873 {
2874 	struct net *net = dev_net(dev);
2875 	struct inet6_dev *idev;
2876 	struct inet6_ifaddr *ifa;
2877 	int state, i;
2878 
2879 	ASSERT_RTNL();
2880 
2881 	rt6_ifdown(net, dev);
2882 	neigh_ifdown(&nd_tbl, dev);
2883 
2884 	idev = __in6_dev_get(dev);
2885 	if (idev == NULL)
2886 		return -ENODEV;
2887 
2888 	/*
2889 	 * Step 1: remove reference to ipv6 device from parent device.
2890 	 *	   Do not dev_put!
2891 	 */
2892 	if (how) {
2893 		idev->dead = 1;
2894 
2895 		/* protected by rtnl_lock */
2896 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
2897 
2898 		/* Step 1.5: remove snmp6 entry */
2899 		snmp6_unregister_dev(idev);
2900 
2901 	}
2902 
2903 	/* Step 2: clear hash table */
2904 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
2905 		struct hlist_head *h = &inet6_addr_lst[i];
2906 		struct hlist_node *n;
2907 
2908 		spin_lock_bh(&addrconf_hash_lock);
2909 	restart:
2910 		hlist_for_each_entry_rcu(ifa, n, h, addr_lst) {
2911 			if (ifa->idev == idev) {
2912 				hlist_del_init_rcu(&ifa->addr_lst);
2913 				addrconf_del_timer(ifa);
2914 				goto restart;
2915 			}
2916 		}
2917 		spin_unlock_bh(&addrconf_hash_lock);
2918 	}
2919 
2920 	write_lock_bh(&idev->lock);
2921 
2922 	/* Step 2: clear flags for stateless addrconf */
2923 	if (!how)
2924 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
2925 
2926 #ifdef CONFIG_IPV6_PRIVACY
2927 	if (how && del_timer(&idev->regen_timer))
2928 		in6_dev_put(idev);
2929 
2930 	/* Step 3: clear tempaddr list */
2931 	while (!list_empty(&idev->tempaddr_list)) {
2932 		ifa = list_first_entry(&idev->tempaddr_list,
2933 				       struct inet6_ifaddr, tmp_list);
2934 		list_del(&ifa->tmp_list);
2935 		write_unlock_bh(&idev->lock);
2936 		spin_lock_bh(&ifa->lock);
2937 
2938 		if (ifa->ifpub) {
2939 			in6_ifa_put(ifa->ifpub);
2940 			ifa->ifpub = NULL;
2941 		}
2942 		spin_unlock_bh(&ifa->lock);
2943 		in6_ifa_put(ifa);
2944 		write_lock_bh(&idev->lock);
2945 	}
2946 #endif
2947 
2948 	while (!list_empty(&idev->addr_list)) {
2949 		ifa = list_first_entry(&idev->addr_list,
2950 				       struct inet6_ifaddr, if_list);
2951 		addrconf_del_timer(ifa);
2952 
2953 		list_del(&ifa->if_list);
2954 
2955 		write_unlock_bh(&idev->lock);
2956 
2957 		spin_lock_bh(&ifa->state_lock);
2958 		state = ifa->state;
2959 		ifa->state = INET6_IFADDR_STATE_DEAD;
2960 		spin_unlock_bh(&ifa->state_lock);
2961 
2962 		if (state != INET6_IFADDR_STATE_DEAD) {
2963 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
2964 			atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifa);
2965 		}
2966 		in6_ifa_put(ifa);
2967 
2968 		write_lock_bh(&idev->lock);
2969 	}
2970 
2971 	write_unlock_bh(&idev->lock);
2972 
2973 	/* Step 5: Discard multicast list */
2974 	if (how)
2975 		ipv6_mc_destroy_dev(idev);
2976 	else
2977 		ipv6_mc_down(idev);
2978 
2979 	idev->tstamp = jiffies;
2980 
2981 	/* Last: Shot the device (if unregistered) */
2982 	if (how) {
2983 		addrconf_sysctl_unregister(idev);
2984 		neigh_parms_release(&nd_tbl, idev->nd_parms);
2985 		neigh_ifdown(&nd_tbl, dev);
2986 		in6_dev_put(idev);
2987 	}
2988 	return 0;
2989 }
2990 
2991 static void addrconf_rs_timer(unsigned long data)
2992 {
2993 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
2994 	struct inet6_dev *idev = ifp->idev;
2995 
2996 	read_lock(&idev->lock);
2997 	if (idev->dead || !(idev->if_flags & IF_READY))
2998 		goto out;
2999 
3000 	if (!ipv6_accept_ra(idev))
3001 		goto out;
3002 
3003 	/* Announcement received after solicitation was sent */
3004 	if (idev->if_flags & IF_RA_RCVD)
3005 		goto out;
3006 
3007 	spin_lock(&ifp->lock);
3008 	if (ifp->probes++ < idev->cnf.rtr_solicits) {
3009 		/* The wait after the last probe can be shorter */
3010 		addrconf_mod_timer(ifp, AC_RS,
3011 				   (ifp->probes == idev->cnf.rtr_solicits) ?
3012 				   idev->cnf.rtr_solicit_delay :
3013 				   idev->cnf.rtr_solicit_interval);
3014 		spin_unlock(&ifp->lock);
3015 
3016 		ndisc_send_rs(idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
3017 	} else {
3018 		spin_unlock(&ifp->lock);
3019 		/*
3020 		 * Note: we do not support deprecated "all on-link"
3021 		 * assumption any longer.
3022 		 */
3023 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3024 	}
3025 
3026 out:
3027 	read_unlock(&idev->lock);
3028 	in6_ifa_put(ifp);
3029 }
3030 
3031 /*
3032  *	Duplicate Address Detection
3033  */
3034 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3035 {
3036 	unsigned long rand_num;
3037 	struct inet6_dev *idev = ifp->idev;
3038 
3039 	if (ifp->flags & IFA_F_OPTIMISTIC)
3040 		rand_num = 0;
3041 	else
3042 		rand_num = net_random() % (idev->cnf.rtr_solicit_delay ? : 1);
3043 
3044 	ifp->probes = idev->cnf.dad_transmits;
3045 	addrconf_mod_timer(ifp, AC_DAD, rand_num);
3046 }
3047 
3048 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3049 {
3050 	struct inet6_dev *idev = ifp->idev;
3051 	struct net_device *dev = idev->dev;
3052 
3053 	addrconf_join_solict(dev, &ifp->addr);
3054 
3055 	net_srandom(ifp->addr.s6_addr32[3]);
3056 
3057 	read_lock_bh(&idev->lock);
3058 	spin_lock(&ifp->lock);
3059 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3060 		goto out;
3061 
3062 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3063 	    idev->cnf.accept_dad < 1 ||
3064 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3065 	    ifp->flags & IFA_F_NODAD) {
3066 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3067 		spin_unlock(&ifp->lock);
3068 		read_unlock_bh(&idev->lock);
3069 
3070 		addrconf_dad_completed(ifp);
3071 		return;
3072 	}
3073 
3074 	if (!(idev->if_flags & IF_READY)) {
3075 		spin_unlock(&ifp->lock);
3076 		read_unlock_bh(&idev->lock);
3077 		/*
3078 		 * If the device is not ready:
3079 		 * - keep it tentative if it is a permanent address.
3080 		 * - otherwise, kill it.
3081 		 */
3082 		in6_ifa_hold(ifp);
3083 		addrconf_dad_stop(ifp, 0);
3084 		return;
3085 	}
3086 
3087 	/*
3088 	 * Optimistic nodes can start receiving
3089 	 * Frames right away
3090 	 */
3091 	if (ifp->flags & IFA_F_OPTIMISTIC)
3092 		ip6_ins_rt(ifp->rt);
3093 
3094 	addrconf_dad_kick(ifp);
3095 out:
3096 	spin_unlock(&ifp->lock);
3097 	read_unlock_bh(&idev->lock);
3098 }
3099 
3100 static void addrconf_dad_timer(unsigned long data)
3101 {
3102 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
3103 	struct inet6_dev *idev = ifp->idev;
3104 	struct in6_addr mcaddr;
3105 
3106 	if (!ifp->probes && addrconf_dad_end(ifp))
3107 		goto out;
3108 
3109 	read_lock(&idev->lock);
3110 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3111 		read_unlock(&idev->lock);
3112 		goto out;
3113 	}
3114 
3115 	spin_lock(&ifp->lock);
3116 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3117 		spin_unlock(&ifp->lock);
3118 		read_unlock(&idev->lock);
3119 		goto out;
3120 	}
3121 
3122 	if (ifp->probes == 0) {
3123 		/*
3124 		 * DAD was successful
3125 		 */
3126 
3127 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3128 		spin_unlock(&ifp->lock);
3129 		read_unlock(&idev->lock);
3130 
3131 		addrconf_dad_completed(ifp);
3132 
3133 		goto out;
3134 	}
3135 
3136 	ifp->probes--;
3137 	addrconf_mod_timer(ifp, AC_DAD, ifp->idev->nd_parms->retrans_time);
3138 	spin_unlock(&ifp->lock);
3139 	read_unlock(&idev->lock);
3140 
3141 	/* send a neighbour solicitation for our addr */
3142 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3143 	ndisc_send_ns(ifp->idev->dev, NULL, &ifp->addr, &mcaddr, &in6addr_any);
3144 out:
3145 	in6_ifa_put(ifp);
3146 }
3147 
3148 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
3149 {
3150 	struct net_device *dev = ifp->idev->dev;
3151 
3152 	/*
3153 	 *	Configure the address for reception. Now it is valid.
3154 	 */
3155 
3156 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
3157 
3158 	/* If added prefix is link local and we are prepared to process
3159 	   router advertisements, start sending router solicitations.
3160 	 */
3161 
3162 	if (ipv6_accept_ra(ifp->idev) &&
3163 	    ifp->idev->cnf.rtr_solicits > 0 &&
3164 	    (dev->flags&IFF_LOOPBACK) == 0 &&
3165 	    (ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL)) {
3166 		/*
3167 		 *	If a host as already performed a random delay
3168 		 *	[...] as part of DAD [...] there is no need
3169 		 *	to delay again before sending the first RS
3170 		 */
3171 		ndisc_send_rs(ifp->idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
3172 
3173 		spin_lock_bh(&ifp->lock);
3174 		ifp->probes = 1;
3175 		ifp->idev->if_flags |= IF_RS_SENT;
3176 		addrconf_mod_timer(ifp, AC_RS, ifp->idev->cnf.rtr_solicit_interval);
3177 		spin_unlock_bh(&ifp->lock);
3178 	}
3179 }
3180 
3181 static void addrconf_dad_run(struct inet6_dev *idev)
3182 {
3183 	struct inet6_ifaddr *ifp;
3184 
3185 	read_lock_bh(&idev->lock);
3186 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3187 		spin_lock(&ifp->lock);
3188 		if (ifp->flags & IFA_F_TENTATIVE &&
3189 		    ifp->state == INET6_IFADDR_STATE_DAD)
3190 			addrconf_dad_kick(ifp);
3191 		spin_unlock(&ifp->lock);
3192 	}
3193 	read_unlock_bh(&idev->lock);
3194 }
3195 
3196 #ifdef CONFIG_PROC_FS
3197 struct if6_iter_state {
3198 	struct seq_net_private p;
3199 	int bucket;
3200 	int offset;
3201 };
3202 
3203 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
3204 {
3205 	struct inet6_ifaddr *ifa = NULL;
3206 	struct if6_iter_state *state = seq->private;
3207 	struct net *net = seq_file_net(seq);
3208 	int p = 0;
3209 
3210 	/* initial bucket if pos is 0 */
3211 	if (pos == 0) {
3212 		state->bucket = 0;
3213 		state->offset = 0;
3214 	}
3215 
3216 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
3217 		struct hlist_node *n;
3218 		hlist_for_each_entry_rcu_bh(ifa, n, &inet6_addr_lst[state->bucket],
3219 					 addr_lst) {
3220 			if (!net_eq(dev_net(ifa->idev->dev), net))
3221 				continue;
3222 			/* sync with offset */
3223 			if (p < state->offset) {
3224 				p++;
3225 				continue;
3226 			}
3227 			state->offset++;
3228 			return ifa;
3229 		}
3230 
3231 		/* prepare for next bucket */
3232 		state->offset = 0;
3233 		p = 0;
3234 	}
3235 	return NULL;
3236 }
3237 
3238 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
3239 					 struct inet6_ifaddr *ifa)
3240 {
3241 	struct if6_iter_state *state = seq->private;
3242 	struct net *net = seq_file_net(seq);
3243 	struct hlist_node *n = &ifa->addr_lst;
3244 
3245 	hlist_for_each_entry_continue_rcu_bh(ifa, n, addr_lst) {
3246 		if (!net_eq(dev_net(ifa->idev->dev), net))
3247 			continue;
3248 		state->offset++;
3249 		return ifa;
3250 	}
3251 
3252 	while (++state->bucket < IN6_ADDR_HSIZE) {
3253 		state->offset = 0;
3254 		hlist_for_each_entry_rcu_bh(ifa, n,
3255 				     &inet6_addr_lst[state->bucket], addr_lst) {
3256 			if (!net_eq(dev_net(ifa->idev->dev), net))
3257 				continue;
3258 			state->offset++;
3259 			return ifa;
3260 		}
3261 	}
3262 
3263 	return NULL;
3264 }
3265 
3266 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
3267 	__acquires(rcu_bh)
3268 {
3269 	rcu_read_lock_bh();
3270 	return if6_get_first(seq, *pos);
3271 }
3272 
3273 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3274 {
3275 	struct inet6_ifaddr *ifa;
3276 
3277 	ifa = if6_get_next(seq, v);
3278 	++*pos;
3279 	return ifa;
3280 }
3281 
3282 static void if6_seq_stop(struct seq_file *seq, void *v)
3283 	__releases(rcu_bh)
3284 {
3285 	rcu_read_unlock_bh();
3286 }
3287 
3288 static int if6_seq_show(struct seq_file *seq, void *v)
3289 {
3290 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
3291 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
3292 		   &ifp->addr,
3293 		   ifp->idev->dev->ifindex,
3294 		   ifp->prefix_len,
3295 		   ifp->scope,
3296 		   ifp->flags,
3297 		   ifp->idev->dev->name);
3298 	return 0;
3299 }
3300 
3301 static const struct seq_operations if6_seq_ops = {
3302 	.start	= if6_seq_start,
3303 	.next	= if6_seq_next,
3304 	.show	= if6_seq_show,
3305 	.stop	= if6_seq_stop,
3306 };
3307 
3308 static int if6_seq_open(struct inode *inode, struct file *file)
3309 {
3310 	return seq_open_net(inode, file, &if6_seq_ops,
3311 			    sizeof(struct if6_iter_state));
3312 }
3313 
3314 static const struct file_operations if6_fops = {
3315 	.owner		= THIS_MODULE,
3316 	.open		= if6_seq_open,
3317 	.read		= seq_read,
3318 	.llseek		= seq_lseek,
3319 	.release	= seq_release_net,
3320 };
3321 
3322 static int __net_init if6_proc_net_init(struct net *net)
3323 {
3324 	if (!proc_net_fops_create(net, "if_inet6", S_IRUGO, &if6_fops))
3325 		return -ENOMEM;
3326 	return 0;
3327 }
3328 
3329 static void __net_exit if6_proc_net_exit(struct net *net)
3330 {
3331        proc_net_remove(net, "if_inet6");
3332 }
3333 
3334 static struct pernet_operations if6_proc_net_ops = {
3335        .init = if6_proc_net_init,
3336        .exit = if6_proc_net_exit,
3337 };
3338 
3339 int __init if6_proc_init(void)
3340 {
3341 	return register_pernet_subsys(&if6_proc_net_ops);
3342 }
3343 
3344 void if6_proc_exit(void)
3345 {
3346 	unregister_pernet_subsys(&if6_proc_net_ops);
3347 }
3348 #endif	/* CONFIG_PROC_FS */
3349 
3350 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3351 /* Check if address is a home address configured on any interface. */
3352 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
3353 {
3354 	int ret = 0;
3355 	struct inet6_ifaddr *ifp = NULL;
3356 	struct hlist_node *n;
3357 	unsigned int hash = inet6_addr_hash(addr);
3358 
3359 	rcu_read_lock_bh();
3360 	hlist_for_each_entry_rcu_bh(ifp, n, &inet6_addr_lst[hash], addr_lst) {
3361 		if (!net_eq(dev_net(ifp->idev->dev), net))
3362 			continue;
3363 		if (ipv6_addr_equal(&ifp->addr, addr) &&
3364 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
3365 			ret = 1;
3366 			break;
3367 		}
3368 	}
3369 	rcu_read_unlock_bh();
3370 	return ret;
3371 }
3372 #endif
3373 
3374 /*
3375  *	Periodic address status verification
3376  */
3377 
3378 static void addrconf_verify(unsigned long foo)
3379 {
3380 	unsigned long now, next, next_sec, next_sched;
3381 	struct inet6_ifaddr *ifp;
3382 	struct hlist_node *node;
3383 	int i;
3384 
3385 	rcu_read_lock_bh();
3386 	spin_lock(&addrconf_verify_lock);
3387 	now = jiffies;
3388 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
3389 
3390 	del_timer(&addr_chk_timer);
3391 
3392 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3393 restart:
3394 		hlist_for_each_entry_rcu_bh(ifp, node,
3395 					 &inet6_addr_lst[i], addr_lst) {
3396 			unsigned long age;
3397 
3398 			if (ifp->flags & IFA_F_PERMANENT)
3399 				continue;
3400 
3401 			spin_lock(&ifp->lock);
3402 			/* We try to batch several events at once. */
3403 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
3404 
3405 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
3406 			    age >= ifp->valid_lft) {
3407 				spin_unlock(&ifp->lock);
3408 				in6_ifa_hold(ifp);
3409 				ipv6_del_addr(ifp);
3410 				goto restart;
3411 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
3412 				spin_unlock(&ifp->lock);
3413 				continue;
3414 			} else if (age >= ifp->prefered_lft) {
3415 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
3416 				int deprecate = 0;
3417 
3418 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
3419 					deprecate = 1;
3420 					ifp->flags |= IFA_F_DEPRECATED;
3421 				}
3422 
3423 				if (time_before(ifp->tstamp + ifp->valid_lft * HZ, next))
3424 					next = ifp->tstamp + ifp->valid_lft * HZ;
3425 
3426 				spin_unlock(&ifp->lock);
3427 
3428 				if (deprecate) {
3429 					in6_ifa_hold(ifp);
3430 
3431 					ipv6_ifa_notify(0, ifp);
3432 					in6_ifa_put(ifp);
3433 					goto restart;
3434 				}
3435 #ifdef CONFIG_IPV6_PRIVACY
3436 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
3437 				   !(ifp->flags&IFA_F_TENTATIVE)) {
3438 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
3439 					ifp->idev->cnf.dad_transmits *
3440 					ifp->idev->nd_parms->retrans_time / HZ;
3441 
3442 				if (age >= ifp->prefered_lft - regen_advance) {
3443 					struct inet6_ifaddr *ifpub = ifp->ifpub;
3444 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3445 						next = ifp->tstamp + ifp->prefered_lft * HZ;
3446 					if (!ifp->regen_count && ifpub) {
3447 						ifp->regen_count++;
3448 						in6_ifa_hold(ifp);
3449 						in6_ifa_hold(ifpub);
3450 						spin_unlock(&ifp->lock);
3451 
3452 						spin_lock(&ifpub->lock);
3453 						ifpub->regen_count = 0;
3454 						spin_unlock(&ifpub->lock);
3455 						ipv6_create_tempaddr(ifpub, ifp);
3456 						in6_ifa_put(ifpub);
3457 						in6_ifa_put(ifp);
3458 						goto restart;
3459 					}
3460 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
3461 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
3462 				spin_unlock(&ifp->lock);
3463 #endif
3464 			} else {
3465 				/* ifp->prefered_lft <= ifp->valid_lft */
3466 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3467 					next = ifp->tstamp + ifp->prefered_lft * HZ;
3468 				spin_unlock(&ifp->lock);
3469 			}
3470 		}
3471 	}
3472 
3473 	next_sec = round_jiffies_up(next);
3474 	next_sched = next;
3475 
3476 	/* If rounded timeout is accurate enough, accept it. */
3477 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
3478 		next_sched = next_sec;
3479 
3480 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
3481 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
3482 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
3483 
3484 	ADBG((KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
3485 	      now, next, next_sec, next_sched));
3486 
3487 	addr_chk_timer.expires = next_sched;
3488 	add_timer(&addr_chk_timer);
3489 	spin_unlock(&addrconf_verify_lock);
3490 	rcu_read_unlock_bh();
3491 }
3492 
3493 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local)
3494 {
3495 	struct in6_addr *pfx = NULL;
3496 
3497 	if (addr)
3498 		pfx = nla_data(addr);
3499 
3500 	if (local) {
3501 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
3502 			pfx = NULL;
3503 		else
3504 			pfx = nla_data(local);
3505 	}
3506 
3507 	return pfx;
3508 }
3509 
3510 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
3511 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
3512 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
3513 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
3514 };
3515 
3516 static int
3517 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
3518 {
3519 	struct net *net = sock_net(skb->sk);
3520 	struct ifaddrmsg *ifm;
3521 	struct nlattr *tb[IFA_MAX+1];
3522 	struct in6_addr *pfx;
3523 	int err;
3524 
3525 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3526 	if (err < 0)
3527 		return err;
3528 
3529 	ifm = nlmsg_data(nlh);
3530 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3531 	if (pfx == NULL)
3532 		return -EINVAL;
3533 
3534 	return inet6_addr_del(net, ifm->ifa_index, pfx, ifm->ifa_prefixlen);
3535 }
3536 
3537 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u8 ifa_flags,
3538 			     u32 prefered_lft, u32 valid_lft)
3539 {
3540 	u32 flags;
3541 	clock_t expires;
3542 	unsigned long timeout;
3543 
3544 	if (!valid_lft || (prefered_lft > valid_lft))
3545 		return -EINVAL;
3546 
3547 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
3548 	if (addrconf_finite_timeout(timeout)) {
3549 		expires = jiffies_to_clock_t(timeout * HZ);
3550 		valid_lft = timeout;
3551 		flags = RTF_EXPIRES;
3552 	} else {
3553 		expires = 0;
3554 		flags = 0;
3555 		ifa_flags |= IFA_F_PERMANENT;
3556 	}
3557 
3558 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
3559 	if (addrconf_finite_timeout(timeout)) {
3560 		if (timeout == 0)
3561 			ifa_flags |= IFA_F_DEPRECATED;
3562 		prefered_lft = timeout;
3563 	}
3564 
3565 	spin_lock_bh(&ifp->lock);
3566 	ifp->flags = (ifp->flags & ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD | IFA_F_HOMEADDRESS)) | ifa_flags;
3567 	ifp->tstamp = jiffies;
3568 	ifp->valid_lft = valid_lft;
3569 	ifp->prefered_lft = prefered_lft;
3570 
3571 	spin_unlock_bh(&ifp->lock);
3572 	if (!(ifp->flags&IFA_F_TENTATIVE))
3573 		ipv6_ifa_notify(0, ifp);
3574 
3575 	addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
3576 			      expires, flags);
3577 	addrconf_verify(0);
3578 
3579 	return 0;
3580 }
3581 
3582 static int
3583 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
3584 {
3585 	struct net *net = sock_net(skb->sk);
3586 	struct ifaddrmsg *ifm;
3587 	struct nlattr *tb[IFA_MAX+1];
3588 	struct in6_addr *pfx;
3589 	struct inet6_ifaddr *ifa;
3590 	struct net_device *dev;
3591 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
3592 	u8 ifa_flags;
3593 	int err;
3594 
3595 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3596 	if (err < 0)
3597 		return err;
3598 
3599 	ifm = nlmsg_data(nlh);
3600 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3601 	if (pfx == NULL)
3602 		return -EINVAL;
3603 
3604 	if (tb[IFA_CACHEINFO]) {
3605 		struct ifa_cacheinfo *ci;
3606 
3607 		ci = nla_data(tb[IFA_CACHEINFO]);
3608 		valid_lft = ci->ifa_valid;
3609 		preferred_lft = ci->ifa_prefered;
3610 	} else {
3611 		preferred_lft = INFINITY_LIFE_TIME;
3612 		valid_lft = INFINITY_LIFE_TIME;
3613 	}
3614 
3615 	dev =  __dev_get_by_index(net, ifm->ifa_index);
3616 	if (dev == NULL)
3617 		return -ENODEV;
3618 
3619 	/* We ignore other flags so far. */
3620 	ifa_flags = ifm->ifa_flags & (IFA_F_NODAD | IFA_F_HOMEADDRESS);
3621 
3622 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
3623 	if (ifa == NULL) {
3624 		/*
3625 		 * It would be best to check for !NLM_F_CREATE here but
3626 		 * userspace alreay relies on not having to provide this.
3627 		 */
3628 		return inet6_addr_add(net, ifm->ifa_index, pfx,
3629 				      ifm->ifa_prefixlen, ifa_flags,
3630 				      preferred_lft, valid_lft);
3631 	}
3632 
3633 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
3634 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
3635 		err = -EEXIST;
3636 	else
3637 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
3638 
3639 	in6_ifa_put(ifa);
3640 
3641 	return err;
3642 }
3643 
3644 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u8 flags,
3645 			  u8 scope, int ifindex)
3646 {
3647 	struct ifaddrmsg *ifm;
3648 
3649 	ifm = nlmsg_data(nlh);
3650 	ifm->ifa_family = AF_INET6;
3651 	ifm->ifa_prefixlen = prefixlen;
3652 	ifm->ifa_flags = flags;
3653 	ifm->ifa_scope = scope;
3654 	ifm->ifa_index = ifindex;
3655 }
3656 
3657 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
3658 			 unsigned long tstamp, u32 preferred, u32 valid)
3659 {
3660 	struct ifa_cacheinfo ci;
3661 
3662 	ci.cstamp = cstamp_delta(cstamp);
3663 	ci.tstamp = cstamp_delta(tstamp);
3664 	ci.ifa_prefered = preferred;
3665 	ci.ifa_valid = valid;
3666 
3667 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
3668 }
3669 
3670 static inline int rt_scope(int ifa_scope)
3671 {
3672 	if (ifa_scope & IFA_HOST)
3673 		return RT_SCOPE_HOST;
3674 	else if (ifa_scope & IFA_LINK)
3675 		return RT_SCOPE_LINK;
3676 	else if (ifa_scope & IFA_SITE)
3677 		return RT_SCOPE_SITE;
3678 	else
3679 		return RT_SCOPE_UNIVERSE;
3680 }
3681 
3682 static inline int inet6_ifaddr_msgsize(void)
3683 {
3684 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
3685 	       + nla_total_size(16) /* IFA_ADDRESS */
3686 	       + nla_total_size(sizeof(struct ifa_cacheinfo));
3687 }
3688 
3689 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
3690 			     u32 portid, u32 seq, int event, unsigned int flags)
3691 {
3692 	struct nlmsghdr  *nlh;
3693 	u32 preferred, valid;
3694 
3695 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3696 	if (nlh == NULL)
3697 		return -EMSGSIZE;
3698 
3699 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
3700 		      ifa->idev->dev->ifindex);
3701 
3702 	if (!(ifa->flags&IFA_F_PERMANENT)) {
3703 		preferred = ifa->prefered_lft;
3704 		valid = ifa->valid_lft;
3705 		if (preferred != INFINITY_LIFE_TIME) {
3706 			long tval = (jiffies - ifa->tstamp)/HZ;
3707 			if (preferred > tval)
3708 				preferred -= tval;
3709 			else
3710 				preferred = 0;
3711 			if (valid != INFINITY_LIFE_TIME) {
3712 				if (valid > tval)
3713 					valid -= tval;
3714 				else
3715 					valid = 0;
3716 			}
3717 		}
3718 	} else {
3719 		preferred = INFINITY_LIFE_TIME;
3720 		valid = INFINITY_LIFE_TIME;
3721 	}
3722 
3723 	if (nla_put(skb, IFA_ADDRESS, 16, &ifa->addr) < 0 ||
3724 	    put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0) {
3725 		nlmsg_cancel(skb, nlh);
3726 		return -EMSGSIZE;
3727 	}
3728 
3729 	return nlmsg_end(skb, nlh);
3730 }
3731 
3732 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
3733 				u32 portid, u32 seq, int event, u16 flags)
3734 {
3735 	struct nlmsghdr  *nlh;
3736 	u8 scope = RT_SCOPE_UNIVERSE;
3737 	int ifindex = ifmca->idev->dev->ifindex;
3738 
3739 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
3740 		scope = RT_SCOPE_SITE;
3741 
3742 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3743 	if (nlh == NULL)
3744 		return -EMSGSIZE;
3745 
3746 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3747 	if (nla_put(skb, IFA_MULTICAST, 16, &ifmca->mca_addr) < 0 ||
3748 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
3749 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3750 		nlmsg_cancel(skb, nlh);
3751 		return -EMSGSIZE;
3752 	}
3753 
3754 	return nlmsg_end(skb, nlh);
3755 }
3756 
3757 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
3758 				u32 portid, u32 seq, int event, unsigned int flags)
3759 {
3760 	struct nlmsghdr  *nlh;
3761 	u8 scope = RT_SCOPE_UNIVERSE;
3762 	int ifindex = ifaca->aca_idev->dev->ifindex;
3763 
3764 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
3765 		scope = RT_SCOPE_SITE;
3766 
3767 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3768 	if (nlh == NULL)
3769 		return -EMSGSIZE;
3770 
3771 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3772 	if (nla_put(skb, IFA_ANYCAST, 16, &ifaca->aca_addr) < 0 ||
3773 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
3774 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3775 		nlmsg_cancel(skb, nlh);
3776 		return -EMSGSIZE;
3777 	}
3778 
3779 	return nlmsg_end(skb, nlh);
3780 }
3781 
3782 enum addr_type_t {
3783 	UNICAST_ADDR,
3784 	MULTICAST_ADDR,
3785 	ANYCAST_ADDR,
3786 };
3787 
3788 /* called with rcu_read_lock() */
3789 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
3790 			  struct netlink_callback *cb, enum addr_type_t type,
3791 			  int s_ip_idx, int *p_ip_idx)
3792 {
3793 	struct ifmcaddr6 *ifmca;
3794 	struct ifacaddr6 *ifaca;
3795 	int err = 1;
3796 	int ip_idx = *p_ip_idx;
3797 
3798 	read_lock_bh(&idev->lock);
3799 	switch (type) {
3800 	case UNICAST_ADDR: {
3801 		struct inet6_ifaddr *ifa;
3802 
3803 		/* unicast address incl. temp addr */
3804 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
3805 			if (++ip_idx < s_ip_idx)
3806 				continue;
3807 			err = inet6_fill_ifaddr(skb, ifa,
3808 						NETLINK_CB(cb->skb).portid,
3809 						cb->nlh->nlmsg_seq,
3810 						RTM_NEWADDR,
3811 						NLM_F_MULTI);
3812 			if (err <= 0)
3813 				break;
3814 		}
3815 		break;
3816 	}
3817 	case MULTICAST_ADDR:
3818 		/* multicast address */
3819 		for (ifmca = idev->mc_list; ifmca;
3820 		     ifmca = ifmca->next, ip_idx++) {
3821 			if (ip_idx < s_ip_idx)
3822 				continue;
3823 			err = inet6_fill_ifmcaddr(skb, ifmca,
3824 						  NETLINK_CB(cb->skb).portid,
3825 						  cb->nlh->nlmsg_seq,
3826 						  RTM_GETMULTICAST,
3827 						  NLM_F_MULTI);
3828 			if (err <= 0)
3829 				break;
3830 		}
3831 		break;
3832 	case ANYCAST_ADDR:
3833 		/* anycast address */
3834 		for (ifaca = idev->ac_list; ifaca;
3835 		     ifaca = ifaca->aca_next, ip_idx++) {
3836 			if (ip_idx < s_ip_idx)
3837 				continue;
3838 			err = inet6_fill_ifacaddr(skb, ifaca,
3839 						  NETLINK_CB(cb->skb).portid,
3840 						  cb->nlh->nlmsg_seq,
3841 						  RTM_GETANYCAST,
3842 						  NLM_F_MULTI);
3843 			if (err <= 0)
3844 				break;
3845 		}
3846 		break;
3847 	default:
3848 		break;
3849 	}
3850 	read_unlock_bh(&idev->lock);
3851 	*p_ip_idx = ip_idx;
3852 	return err;
3853 }
3854 
3855 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
3856 			   enum addr_type_t type)
3857 {
3858 	struct net *net = sock_net(skb->sk);
3859 	int h, s_h;
3860 	int idx, ip_idx;
3861 	int s_idx, s_ip_idx;
3862 	struct net_device *dev;
3863 	struct inet6_dev *idev;
3864 	struct hlist_head *head;
3865 	struct hlist_node *node;
3866 
3867 	s_h = cb->args[0];
3868 	s_idx = idx = cb->args[1];
3869 	s_ip_idx = ip_idx = cb->args[2];
3870 
3871 	rcu_read_lock();
3872 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
3873 		idx = 0;
3874 		head = &net->dev_index_head[h];
3875 		hlist_for_each_entry_rcu(dev, node, head, index_hlist) {
3876 			if (idx < s_idx)
3877 				goto cont;
3878 			if (h > s_h || idx > s_idx)
3879 				s_ip_idx = 0;
3880 			ip_idx = 0;
3881 			idev = __in6_dev_get(dev);
3882 			if (!idev)
3883 				goto cont;
3884 
3885 			if (in6_dump_addrs(idev, skb, cb, type,
3886 					   s_ip_idx, &ip_idx) <= 0)
3887 				goto done;
3888 cont:
3889 			idx++;
3890 		}
3891 	}
3892 done:
3893 	rcu_read_unlock();
3894 	cb->args[0] = h;
3895 	cb->args[1] = idx;
3896 	cb->args[2] = ip_idx;
3897 
3898 	return skb->len;
3899 }
3900 
3901 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
3902 {
3903 	enum addr_type_t type = UNICAST_ADDR;
3904 
3905 	return inet6_dump_addr(skb, cb, type);
3906 }
3907 
3908 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
3909 {
3910 	enum addr_type_t type = MULTICAST_ADDR;
3911 
3912 	return inet6_dump_addr(skb, cb, type);
3913 }
3914 
3915 
3916 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
3917 {
3918 	enum addr_type_t type = ANYCAST_ADDR;
3919 
3920 	return inet6_dump_addr(skb, cb, type);
3921 }
3922 
3923 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
3924 			     void *arg)
3925 {
3926 	struct net *net = sock_net(in_skb->sk);
3927 	struct ifaddrmsg *ifm;
3928 	struct nlattr *tb[IFA_MAX+1];
3929 	struct in6_addr *addr = NULL;
3930 	struct net_device *dev = NULL;
3931 	struct inet6_ifaddr *ifa;
3932 	struct sk_buff *skb;
3933 	int err;
3934 
3935 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3936 	if (err < 0)
3937 		goto errout;
3938 
3939 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3940 	if (addr == NULL) {
3941 		err = -EINVAL;
3942 		goto errout;
3943 	}
3944 
3945 	ifm = nlmsg_data(nlh);
3946 	if (ifm->ifa_index)
3947 		dev = __dev_get_by_index(net, ifm->ifa_index);
3948 
3949 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
3950 	if (!ifa) {
3951 		err = -EADDRNOTAVAIL;
3952 		goto errout;
3953 	}
3954 
3955 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
3956 	if (!skb) {
3957 		err = -ENOBUFS;
3958 		goto errout_ifa;
3959 	}
3960 
3961 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
3962 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
3963 	if (err < 0) {
3964 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
3965 		WARN_ON(err == -EMSGSIZE);
3966 		kfree_skb(skb);
3967 		goto errout_ifa;
3968 	}
3969 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3970 errout_ifa:
3971 	in6_ifa_put(ifa);
3972 errout:
3973 	return err;
3974 }
3975 
3976 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
3977 {
3978 	struct sk_buff *skb;
3979 	struct net *net = dev_net(ifa->idev->dev);
3980 	int err = -ENOBUFS;
3981 
3982 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
3983 	if (skb == NULL)
3984 		goto errout;
3985 
3986 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
3987 	if (err < 0) {
3988 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
3989 		WARN_ON(err == -EMSGSIZE);
3990 		kfree_skb(skb);
3991 		goto errout;
3992 	}
3993 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
3994 	return;
3995 errout:
3996 	if (err < 0)
3997 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
3998 }
3999 
4000 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
4001 				__s32 *array, int bytes)
4002 {
4003 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4004 
4005 	memset(array, 0, bytes);
4006 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4007 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4008 	array[DEVCONF_MTU6] = cnf->mtu6;
4009 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4010 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4011 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4012 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4013 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4014 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
4015 		jiffies_to_msecs(cnf->rtr_solicit_interval);
4016 	array[DEVCONF_RTR_SOLICIT_DELAY] =
4017 		jiffies_to_msecs(cnf->rtr_solicit_delay);
4018 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
4019 #ifdef CONFIG_IPV6_PRIVACY
4020 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
4021 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
4022 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
4023 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
4024 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
4025 #endif
4026 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
4027 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
4028 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
4029 #ifdef CONFIG_IPV6_ROUTER_PREF
4030 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
4031 	array[DEVCONF_RTR_PROBE_INTERVAL] =
4032 		jiffies_to_msecs(cnf->rtr_probe_interval);
4033 #ifdef CONFIG_IPV6_ROUTE_INFO
4034 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
4035 #endif
4036 #endif
4037 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
4038 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
4039 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4040 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
4041 #endif
4042 #ifdef CONFIG_IPV6_MROUTE
4043 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
4044 #endif
4045 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
4046 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
4047 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
4048 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
4049 }
4050 
4051 static inline size_t inet6_ifla6_size(void)
4052 {
4053 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
4054 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
4055 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
4056 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
4057 	     + nla_total_size(ICMP6_MIB_MAX * 8); /* IFLA_INET6_ICMP6STATS */
4058 }
4059 
4060 static inline size_t inet6_if_nlmsg_size(void)
4061 {
4062 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
4063 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
4064 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
4065 	       + nla_total_size(4) /* IFLA_MTU */
4066 	       + nla_total_size(4) /* IFLA_LINK */
4067 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
4068 }
4069 
4070 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
4071 				      int items, int bytes)
4072 {
4073 	int i;
4074 	int pad = bytes - sizeof(u64) * items;
4075 	BUG_ON(pad < 0);
4076 
4077 	/* Use put_unaligned() because stats may not be aligned for u64. */
4078 	put_unaligned(items, &stats[0]);
4079 	for (i = 1; i < items; i++)
4080 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
4081 
4082 	memset(&stats[items], 0, pad);
4083 }
4084 
4085 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu **mib,
4086 				      int items, int bytes, size_t syncpoff)
4087 {
4088 	int i;
4089 	int pad = bytes - sizeof(u64) * items;
4090 	BUG_ON(pad < 0);
4091 
4092 	/* Use put_unaligned() because stats may not be aligned for u64. */
4093 	put_unaligned(items, &stats[0]);
4094 	for (i = 1; i < items; i++)
4095 		put_unaligned(snmp_fold_field64(mib, i, syncpoff), &stats[i]);
4096 
4097 	memset(&stats[items], 0, pad);
4098 }
4099 
4100 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
4101 			     int bytes)
4102 {
4103 	switch (attrtype) {
4104 	case IFLA_INET6_STATS:
4105 		__snmp6_fill_stats64(stats, (void __percpu **)idev->stats.ipv6,
4106 				     IPSTATS_MIB_MAX, bytes, offsetof(struct ipstats_mib, syncp));
4107 		break;
4108 	case IFLA_INET6_ICMP6STATS:
4109 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, ICMP6_MIB_MAX, bytes);
4110 		break;
4111 	}
4112 }
4113 
4114 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev)
4115 {
4116 	struct nlattr *nla;
4117 	struct ifla_cacheinfo ci;
4118 
4119 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
4120 		goto nla_put_failure;
4121 	ci.max_reasm_len = IPV6_MAXPLEN;
4122 	ci.tstamp = cstamp_delta(idev->tstamp);
4123 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
4124 	ci.retrans_time = jiffies_to_msecs(idev->nd_parms->retrans_time);
4125 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
4126 		goto nla_put_failure;
4127 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
4128 	if (nla == NULL)
4129 		goto nla_put_failure;
4130 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
4131 
4132 	/* XXX - MC not implemented */
4133 
4134 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
4135 	if (nla == NULL)
4136 		goto nla_put_failure;
4137 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
4138 
4139 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
4140 	if (nla == NULL)
4141 		goto nla_put_failure;
4142 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
4143 
4144 	return 0;
4145 
4146 nla_put_failure:
4147 	return -EMSGSIZE;
4148 }
4149 
4150 static size_t inet6_get_link_af_size(const struct net_device *dev)
4151 {
4152 	if (!__in6_dev_get(dev))
4153 		return 0;
4154 
4155 	return inet6_ifla6_size();
4156 }
4157 
4158 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
4159 {
4160 	struct inet6_dev *idev = __in6_dev_get(dev);
4161 
4162 	if (!idev)
4163 		return -ENODATA;
4164 
4165 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4166 		return -EMSGSIZE;
4167 
4168 	return 0;
4169 }
4170 
4171 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
4172 			     u32 portid, u32 seq, int event, unsigned int flags)
4173 {
4174 	struct net_device *dev = idev->dev;
4175 	struct ifinfomsg *hdr;
4176 	struct nlmsghdr *nlh;
4177 	void *protoinfo;
4178 
4179 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
4180 	if (nlh == NULL)
4181 		return -EMSGSIZE;
4182 
4183 	hdr = nlmsg_data(nlh);
4184 	hdr->ifi_family = AF_INET6;
4185 	hdr->__ifi_pad = 0;
4186 	hdr->ifi_type = dev->type;
4187 	hdr->ifi_index = dev->ifindex;
4188 	hdr->ifi_flags = dev_get_flags(dev);
4189 	hdr->ifi_change = 0;
4190 
4191 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
4192 	    (dev->addr_len &&
4193 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
4194 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
4195 	    (dev->ifindex != dev->iflink &&
4196 	     nla_put_u32(skb, IFLA_LINK, dev->iflink)))
4197 		goto nla_put_failure;
4198 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
4199 	if (protoinfo == NULL)
4200 		goto nla_put_failure;
4201 
4202 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4203 		goto nla_put_failure;
4204 
4205 	nla_nest_end(skb, protoinfo);
4206 	return nlmsg_end(skb, nlh);
4207 
4208 nla_put_failure:
4209 	nlmsg_cancel(skb, nlh);
4210 	return -EMSGSIZE;
4211 }
4212 
4213 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
4214 {
4215 	struct net *net = sock_net(skb->sk);
4216 	int h, s_h;
4217 	int idx = 0, s_idx;
4218 	struct net_device *dev;
4219 	struct inet6_dev *idev;
4220 	struct hlist_head *head;
4221 	struct hlist_node *node;
4222 
4223 	s_h = cb->args[0];
4224 	s_idx = cb->args[1];
4225 
4226 	rcu_read_lock();
4227 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4228 		idx = 0;
4229 		head = &net->dev_index_head[h];
4230 		hlist_for_each_entry_rcu(dev, node, head, index_hlist) {
4231 			if (idx < s_idx)
4232 				goto cont;
4233 			idev = __in6_dev_get(dev);
4234 			if (!idev)
4235 				goto cont;
4236 			if (inet6_fill_ifinfo(skb, idev,
4237 					      NETLINK_CB(cb->skb).portid,
4238 					      cb->nlh->nlmsg_seq,
4239 					      RTM_NEWLINK, NLM_F_MULTI) <= 0)
4240 				goto out;
4241 cont:
4242 			idx++;
4243 		}
4244 	}
4245 out:
4246 	rcu_read_unlock();
4247 	cb->args[1] = idx;
4248 	cb->args[0] = h;
4249 
4250 	return skb->len;
4251 }
4252 
4253 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
4254 {
4255 	struct sk_buff *skb;
4256 	struct net *net = dev_net(idev->dev);
4257 	int err = -ENOBUFS;
4258 
4259 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
4260 	if (skb == NULL)
4261 		goto errout;
4262 
4263 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
4264 	if (err < 0) {
4265 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
4266 		WARN_ON(err == -EMSGSIZE);
4267 		kfree_skb(skb);
4268 		goto errout;
4269 	}
4270 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
4271 	return;
4272 errout:
4273 	if (err < 0)
4274 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
4275 }
4276 
4277 static inline size_t inet6_prefix_nlmsg_size(void)
4278 {
4279 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
4280 	       + nla_total_size(sizeof(struct in6_addr))
4281 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
4282 }
4283 
4284 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
4285 			     struct prefix_info *pinfo, u32 portid, u32 seq,
4286 			     int event, unsigned int flags)
4287 {
4288 	struct prefixmsg *pmsg;
4289 	struct nlmsghdr *nlh;
4290 	struct prefix_cacheinfo	ci;
4291 
4292 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
4293 	if (nlh == NULL)
4294 		return -EMSGSIZE;
4295 
4296 	pmsg = nlmsg_data(nlh);
4297 	pmsg->prefix_family = AF_INET6;
4298 	pmsg->prefix_pad1 = 0;
4299 	pmsg->prefix_pad2 = 0;
4300 	pmsg->prefix_ifindex = idev->dev->ifindex;
4301 	pmsg->prefix_len = pinfo->prefix_len;
4302 	pmsg->prefix_type = pinfo->type;
4303 	pmsg->prefix_pad3 = 0;
4304 	pmsg->prefix_flags = 0;
4305 	if (pinfo->onlink)
4306 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
4307 	if (pinfo->autoconf)
4308 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
4309 
4310 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
4311 		goto nla_put_failure;
4312 	ci.preferred_time = ntohl(pinfo->prefered);
4313 	ci.valid_time = ntohl(pinfo->valid);
4314 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
4315 		goto nla_put_failure;
4316 	return nlmsg_end(skb, nlh);
4317 
4318 nla_put_failure:
4319 	nlmsg_cancel(skb, nlh);
4320 	return -EMSGSIZE;
4321 }
4322 
4323 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
4324 			 struct prefix_info *pinfo)
4325 {
4326 	struct sk_buff *skb;
4327 	struct net *net = dev_net(idev->dev);
4328 	int err = -ENOBUFS;
4329 
4330 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
4331 	if (skb == NULL)
4332 		goto errout;
4333 
4334 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
4335 	if (err < 0) {
4336 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
4337 		WARN_ON(err == -EMSGSIZE);
4338 		kfree_skb(skb);
4339 		goto errout;
4340 	}
4341 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
4342 	return;
4343 errout:
4344 	if (err < 0)
4345 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
4346 }
4347 
4348 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4349 {
4350 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
4351 
4352 	switch (event) {
4353 	case RTM_NEWADDR:
4354 		/*
4355 		 * If the address was optimistic
4356 		 * we inserted the route at the start of
4357 		 * our DAD process, so we don't need
4358 		 * to do it again
4359 		 */
4360 		if (!(ifp->rt->rt6i_node))
4361 			ip6_ins_rt(ifp->rt);
4362 		if (ifp->idev->cnf.forwarding)
4363 			addrconf_join_anycast(ifp);
4364 		break;
4365 	case RTM_DELADDR:
4366 		if (ifp->idev->cnf.forwarding)
4367 			addrconf_leave_anycast(ifp);
4368 		addrconf_leave_solict(ifp->idev, &ifp->addr);
4369 		dst_hold(&ifp->rt->dst);
4370 
4371 		if (ip6_del_rt(ifp->rt))
4372 			dst_free(&ifp->rt->dst);
4373 		break;
4374 	}
4375 }
4376 
4377 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4378 {
4379 	rcu_read_lock_bh();
4380 	if (likely(ifp->idev->dead == 0))
4381 		__ipv6_ifa_notify(event, ifp);
4382 	rcu_read_unlock_bh();
4383 }
4384 
4385 #ifdef CONFIG_SYSCTL
4386 
4387 static
4388 int addrconf_sysctl_forward(ctl_table *ctl, int write,
4389 			   void __user *buffer, size_t *lenp, loff_t *ppos)
4390 {
4391 	int *valp = ctl->data;
4392 	int val = *valp;
4393 	loff_t pos = *ppos;
4394 	ctl_table lctl;
4395 	int ret;
4396 
4397 	/*
4398 	 * ctl->data points to idev->cnf.forwarding, we should
4399 	 * not modify it until we get the rtnl lock.
4400 	 */
4401 	lctl = *ctl;
4402 	lctl.data = &val;
4403 
4404 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4405 
4406 	if (write)
4407 		ret = addrconf_fixup_forwarding(ctl, valp, val);
4408 	if (ret)
4409 		*ppos = pos;
4410 	return ret;
4411 }
4412 
4413 static void dev_disable_change(struct inet6_dev *idev)
4414 {
4415 	if (!idev || !idev->dev)
4416 		return;
4417 
4418 	if (idev->cnf.disable_ipv6)
4419 		addrconf_notify(NULL, NETDEV_DOWN, idev->dev);
4420 	else
4421 		addrconf_notify(NULL, NETDEV_UP, idev->dev);
4422 }
4423 
4424 static void addrconf_disable_change(struct net *net, __s32 newf)
4425 {
4426 	struct net_device *dev;
4427 	struct inet6_dev *idev;
4428 
4429 	rcu_read_lock();
4430 	for_each_netdev_rcu(net, dev) {
4431 		idev = __in6_dev_get(dev);
4432 		if (idev) {
4433 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
4434 			idev->cnf.disable_ipv6 = newf;
4435 			if (changed)
4436 				dev_disable_change(idev);
4437 		}
4438 	}
4439 	rcu_read_unlock();
4440 }
4441 
4442 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
4443 {
4444 	struct net *net;
4445 	int old;
4446 
4447 	if (!rtnl_trylock())
4448 		return restart_syscall();
4449 
4450 	net = (struct net *)table->extra2;
4451 	old = *p;
4452 	*p = newf;
4453 
4454 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
4455 		rtnl_unlock();
4456 		return 0;
4457 	}
4458 
4459 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
4460 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
4461 		addrconf_disable_change(net, newf);
4462 	} else if ((!newf) ^ (!old))
4463 		dev_disable_change((struct inet6_dev *)table->extra1);
4464 
4465 	rtnl_unlock();
4466 	return 0;
4467 }
4468 
4469 static
4470 int addrconf_sysctl_disable(ctl_table *ctl, int write,
4471 			    void __user *buffer, size_t *lenp, loff_t *ppos)
4472 {
4473 	int *valp = ctl->data;
4474 	int val = *valp;
4475 	loff_t pos = *ppos;
4476 	ctl_table lctl;
4477 	int ret;
4478 
4479 	/*
4480 	 * ctl->data points to idev->cnf.disable_ipv6, we should
4481 	 * not modify it until we get the rtnl lock.
4482 	 */
4483 	lctl = *ctl;
4484 	lctl.data = &val;
4485 
4486 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4487 
4488 	if (write)
4489 		ret = addrconf_disable_ipv6(ctl, valp, val);
4490 	if (ret)
4491 		*ppos = pos;
4492 	return ret;
4493 }
4494 
4495 static struct addrconf_sysctl_table
4496 {
4497 	struct ctl_table_header *sysctl_header;
4498 	ctl_table addrconf_vars[DEVCONF_MAX+1];
4499 } addrconf_sysctl __read_mostly = {
4500 	.sysctl_header = NULL,
4501 	.addrconf_vars = {
4502 		{
4503 			.procname	= "forwarding",
4504 			.data		= &ipv6_devconf.forwarding,
4505 			.maxlen		= sizeof(int),
4506 			.mode		= 0644,
4507 			.proc_handler	= addrconf_sysctl_forward,
4508 		},
4509 		{
4510 			.procname	= "hop_limit",
4511 			.data		= &ipv6_devconf.hop_limit,
4512 			.maxlen		= sizeof(int),
4513 			.mode		= 0644,
4514 			.proc_handler	= proc_dointvec,
4515 		},
4516 		{
4517 			.procname	= "mtu",
4518 			.data		= &ipv6_devconf.mtu6,
4519 			.maxlen		= sizeof(int),
4520 			.mode		= 0644,
4521 			.proc_handler	= proc_dointvec,
4522 		},
4523 		{
4524 			.procname	= "accept_ra",
4525 			.data		= &ipv6_devconf.accept_ra,
4526 			.maxlen		= sizeof(int),
4527 			.mode		= 0644,
4528 			.proc_handler	= proc_dointvec,
4529 		},
4530 		{
4531 			.procname	= "accept_redirects",
4532 			.data		= &ipv6_devconf.accept_redirects,
4533 			.maxlen		= sizeof(int),
4534 			.mode		= 0644,
4535 			.proc_handler	= proc_dointvec,
4536 		},
4537 		{
4538 			.procname	= "autoconf",
4539 			.data		= &ipv6_devconf.autoconf,
4540 			.maxlen		= sizeof(int),
4541 			.mode		= 0644,
4542 			.proc_handler	= proc_dointvec,
4543 		},
4544 		{
4545 			.procname	= "dad_transmits",
4546 			.data		= &ipv6_devconf.dad_transmits,
4547 			.maxlen		= sizeof(int),
4548 			.mode		= 0644,
4549 			.proc_handler	= proc_dointvec,
4550 		},
4551 		{
4552 			.procname	= "router_solicitations",
4553 			.data		= &ipv6_devconf.rtr_solicits,
4554 			.maxlen		= sizeof(int),
4555 			.mode		= 0644,
4556 			.proc_handler	= proc_dointvec,
4557 		},
4558 		{
4559 			.procname	= "router_solicitation_interval",
4560 			.data		= &ipv6_devconf.rtr_solicit_interval,
4561 			.maxlen		= sizeof(int),
4562 			.mode		= 0644,
4563 			.proc_handler	= proc_dointvec_jiffies,
4564 		},
4565 		{
4566 			.procname	= "router_solicitation_delay",
4567 			.data		= &ipv6_devconf.rtr_solicit_delay,
4568 			.maxlen		= sizeof(int),
4569 			.mode		= 0644,
4570 			.proc_handler	= proc_dointvec_jiffies,
4571 		},
4572 		{
4573 			.procname	= "force_mld_version",
4574 			.data		= &ipv6_devconf.force_mld_version,
4575 			.maxlen		= sizeof(int),
4576 			.mode		= 0644,
4577 			.proc_handler	= proc_dointvec,
4578 		},
4579 #ifdef CONFIG_IPV6_PRIVACY
4580 		{
4581 			.procname	= "use_tempaddr",
4582 			.data		= &ipv6_devconf.use_tempaddr,
4583 			.maxlen		= sizeof(int),
4584 			.mode		= 0644,
4585 			.proc_handler	= proc_dointvec,
4586 		},
4587 		{
4588 			.procname	= "temp_valid_lft",
4589 			.data		= &ipv6_devconf.temp_valid_lft,
4590 			.maxlen		= sizeof(int),
4591 			.mode		= 0644,
4592 			.proc_handler	= proc_dointvec,
4593 		},
4594 		{
4595 			.procname	= "temp_prefered_lft",
4596 			.data		= &ipv6_devconf.temp_prefered_lft,
4597 			.maxlen		= sizeof(int),
4598 			.mode		= 0644,
4599 			.proc_handler	= proc_dointvec,
4600 		},
4601 		{
4602 			.procname	= "regen_max_retry",
4603 			.data		= &ipv6_devconf.regen_max_retry,
4604 			.maxlen		= sizeof(int),
4605 			.mode		= 0644,
4606 			.proc_handler	= proc_dointvec,
4607 		},
4608 		{
4609 			.procname	= "max_desync_factor",
4610 			.data		= &ipv6_devconf.max_desync_factor,
4611 			.maxlen		= sizeof(int),
4612 			.mode		= 0644,
4613 			.proc_handler	= proc_dointvec,
4614 		},
4615 #endif
4616 		{
4617 			.procname	= "max_addresses",
4618 			.data		= &ipv6_devconf.max_addresses,
4619 			.maxlen		= sizeof(int),
4620 			.mode		= 0644,
4621 			.proc_handler	= proc_dointvec,
4622 		},
4623 		{
4624 			.procname	= "accept_ra_defrtr",
4625 			.data		= &ipv6_devconf.accept_ra_defrtr,
4626 			.maxlen		= sizeof(int),
4627 			.mode		= 0644,
4628 			.proc_handler	= proc_dointvec,
4629 		},
4630 		{
4631 			.procname	= "accept_ra_pinfo",
4632 			.data		= &ipv6_devconf.accept_ra_pinfo,
4633 			.maxlen		= sizeof(int),
4634 			.mode		= 0644,
4635 			.proc_handler	= proc_dointvec,
4636 		},
4637 #ifdef CONFIG_IPV6_ROUTER_PREF
4638 		{
4639 			.procname	= "accept_ra_rtr_pref",
4640 			.data		= &ipv6_devconf.accept_ra_rtr_pref,
4641 			.maxlen		= sizeof(int),
4642 			.mode		= 0644,
4643 			.proc_handler	= proc_dointvec,
4644 		},
4645 		{
4646 			.procname	= "router_probe_interval",
4647 			.data		= &ipv6_devconf.rtr_probe_interval,
4648 			.maxlen		= sizeof(int),
4649 			.mode		= 0644,
4650 			.proc_handler	= proc_dointvec_jiffies,
4651 		},
4652 #ifdef CONFIG_IPV6_ROUTE_INFO
4653 		{
4654 			.procname	= "accept_ra_rt_info_max_plen",
4655 			.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
4656 			.maxlen		= sizeof(int),
4657 			.mode		= 0644,
4658 			.proc_handler	= proc_dointvec,
4659 		},
4660 #endif
4661 #endif
4662 		{
4663 			.procname	= "proxy_ndp",
4664 			.data		= &ipv6_devconf.proxy_ndp,
4665 			.maxlen		= sizeof(int),
4666 			.mode		= 0644,
4667 			.proc_handler	= proc_dointvec,
4668 		},
4669 		{
4670 			.procname	= "accept_source_route",
4671 			.data		= &ipv6_devconf.accept_source_route,
4672 			.maxlen		= sizeof(int),
4673 			.mode		= 0644,
4674 			.proc_handler	= proc_dointvec,
4675 		},
4676 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4677 		{
4678 			.procname       = "optimistic_dad",
4679 			.data           = &ipv6_devconf.optimistic_dad,
4680 			.maxlen         = sizeof(int),
4681 			.mode           = 0644,
4682 			.proc_handler   = proc_dointvec,
4683 
4684 		},
4685 #endif
4686 #ifdef CONFIG_IPV6_MROUTE
4687 		{
4688 			.procname	= "mc_forwarding",
4689 			.data		= &ipv6_devconf.mc_forwarding,
4690 			.maxlen		= sizeof(int),
4691 			.mode		= 0444,
4692 			.proc_handler	= proc_dointvec,
4693 		},
4694 #endif
4695 		{
4696 			.procname	= "disable_ipv6",
4697 			.data		= &ipv6_devconf.disable_ipv6,
4698 			.maxlen		= sizeof(int),
4699 			.mode		= 0644,
4700 			.proc_handler	= addrconf_sysctl_disable,
4701 		},
4702 		{
4703 			.procname	= "accept_dad",
4704 			.data		= &ipv6_devconf.accept_dad,
4705 			.maxlen		= sizeof(int),
4706 			.mode		= 0644,
4707 			.proc_handler	= proc_dointvec,
4708 		},
4709 		{
4710 			.procname       = "force_tllao",
4711 			.data           = &ipv6_devconf.force_tllao,
4712 			.maxlen         = sizeof(int),
4713 			.mode           = 0644,
4714 			.proc_handler   = proc_dointvec
4715 		},
4716 		{
4717 			.procname       = "ndisc_notify",
4718 			.data           = &ipv6_devconf.ndisc_notify,
4719 			.maxlen         = sizeof(int),
4720 			.mode           = 0644,
4721 			.proc_handler   = proc_dointvec
4722 		},
4723 		{
4724 			/* sentinel */
4725 		}
4726 	},
4727 };
4728 
4729 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
4730 		struct inet6_dev *idev, struct ipv6_devconf *p)
4731 {
4732 	int i;
4733 	struct addrconf_sysctl_table *t;
4734 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
4735 
4736 	t = kmemdup(&addrconf_sysctl, sizeof(*t), GFP_KERNEL);
4737 	if (t == NULL)
4738 		goto out;
4739 
4740 	for (i = 0; t->addrconf_vars[i].data; i++) {
4741 		t->addrconf_vars[i].data += (char *)p - (char *)&ipv6_devconf;
4742 		t->addrconf_vars[i].extra1 = idev; /* embedded; no ref */
4743 		t->addrconf_vars[i].extra2 = net;
4744 	}
4745 
4746 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
4747 
4748 	t->sysctl_header = register_net_sysctl(net, path, t->addrconf_vars);
4749 	if (t->sysctl_header == NULL)
4750 		goto free;
4751 
4752 	p->sysctl = t;
4753 	return 0;
4754 
4755 free:
4756 	kfree(t);
4757 out:
4758 	return -ENOBUFS;
4759 }
4760 
4761 static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
4762 {
4763 	struct addrconf_sysctl_table *t;
4764 
4765 	if (p->sysctl == NULL)
4766 		return;
4767 
4768 	t = p->sysctl;
4769 	p->sysctl = NULL;
4770 	unregister_net_sysctl_table(t->sysctl_header);
4771 	kfree(t);
4772 }
4773 
4774 static void addrconf_sysctl_register(struct inet6_dev *idev)
4775 {
4776 	neigh_sysctl_register(idev->dev, idev->nd_parms, "ipv6",
4777 			      &ndisc_ifinfo_sysctl_change);
4778 	__addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
4779 					idev, &idev->cnf);
4780 }
4781 
4782 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
4783 {
4784 	__addrconf_sysctl_unregister(&idev->cnf);
4785 	neigh_sysctl_unregister(idev->nd_parms);
4786 }
4787 
4788 
4789 #endif
4790 
4791 static int __net_init addrconf_init_net(struct net *net)
4792 {
4793 	int err;
4794 	struct ipv6_devconf *all, *dflt;
4795 
4796 	err = -ENOMEM;
4797 	all = &ipv6_devconf;
4798 	dflt = &ipv6_devconf_dflt;
4799 
4800 	if (!net_eq(net, &init_net)) {
4801 		all = kmemdup(all, sizeof(ipv6_devconf), GFP_KERNEL);
4802 		if (all == NULL)
4803 			goto err_alloc_all;
4804 
4805 		dflt = kmemdup(dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
4806 		if (dflt == NULL)
4807 			goto err_alloc_dflt;
4808 	} else {
4809 		/* these will be inherited by all namespaces */
4810 		dflt->autoconf = ipv6_defaults.autoconf;
4811 		dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
4812 	}
4813 
4814 	net->ipv6.devconf_all = all;
4815 	net->ipv6.devconf_dflt = dflt;
4816 
4817 #ifdef CONFIG_SYSCTL
4818 	err = __addrconf_sysctl_register(net, "all", NULL, all);
4819 	if (err < 0)
4820 		goto err_reg_all;
4821 
4822 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
4823 	if (err < 0)
4824 		goto err_reg_dflt;
4825 #endif
4826 	return 0;
4827 
4828 #ifdef CONFIG_SYSCTL
4829 err_reg_dflt:
4830 	__addrconf_sysctl_unregister(all);
4831 err_reg_all:
4832 	kfree(dflt);
4833 #endif
4834 err_alloc_dflt:
4835 	kfree(all);
4836 err_alloc_all:
4837 	return err;
4838 }
4839 
4840 static void __net_exit addrconf_exit_net(struct net *net)
4841 {
4842 #ifdef CONFIG_SYSCTL
4843 	__addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
4844 	__addrconf_sysctl_unregister(net->ipv6.devconf_all);
4845 #endif
4846 	if (!net_eq(net, &init_net)) {
4847 		kfree(net->ipv6.devconf_dflt);
4848 		kfree(net->ipv6.devconf_all);
4849 	}
4850 }
4851 
4852 static struct pernet_operations addrconf_ops = {
4853 	.init = addrconf_init_net,
4854 	.exit = addrconf_exit_net,
4855 };
4856 
4857 /*
4858  *      Device notifier
4859  */
4860 
4861 int register_inet6addr_notifier(struct notifier_block *nb)
4862 {
4863 	return atomic_notifier_chain_register(&inet6addr_chain, nb);
4864 }
4865 EXPORT_SYMBOL(register_inet6addr_notifier);
4866 
4867 int unregister_inet6addr_notifier(struct notifier_block *nb)
4868 {
4869 	return atomic_notifier_chain_unregister(&inet6addr_chain, nb);
4870 }
4871 EXPORT_SYMBOL(unregister_inet6addr_notifier);
4872 
4873 static struct rtnl_af_ops inet6_ops = {
4874 	.family		  = AF_INET6,
4875 	.fill_link_af	  = inet6_fill_link_af,
4876 	.get_link_af_size = inet6_get_link_af_size,
4877 };
4878 
4879 /*
4880  *	Init / cleanup code
4881  */
4882 
4883 int __init addrconf_init(void)
4884 {
4885 	int i, err;
4886 
4887 	err = ipv6_addr_label_init();
4888 	if (err < 0) {
4889 		pr_crit("%s: cannot initialize default policy table: %d\n",
4890 			__func__, err);
4891 		goto out;
4892 	}
4893 
4894 	err = register_pernet_subsys(&addrconf_ops);
4895 	if (err < 0)
4896 		goto out_addrlabel;
4897 
4898 	/* The addrconf netdev notifier requires that loopback_dev
4899 	 * has it's ipv6 private information allocated and setup
4900 	 * before it can bring up and give link-local addresses
4901 	 * to other devices which are up.
4902 	 *
4903 	 * Unfortunately, loopback_dev is not necessarily the first
4904 	 * entry in the global dev_base list of net devices.  In fact,
4905 	 * it is likely to be the very last entry on that list.
4906 	 * So this causes the notifier registry below to try and
4907 	 * give link-local addresses to all devices besides loopback_dev
4908 	 * first, then loopback_dev, which cases all the non-loopback_dev
4909 	 * devices to fail to get a link-local address.
4910 	 *
4911 	 * So, as a temporary fix, allocate the ipv6 structure for
4912 	 * loopback_dev first by hand.
4913 	 * Longer term, all of the dependencies ipv6 has upon the loopback
4914 	 * device and it being up should be removed.
4915 	 */
4916 	rtnl_lock();
4917 	if (!ipv6_add_dev(init_net.loopback_dev))
4918 		err = -ENOMEM;
4919 	rtnl_unlock();
4920 	if (err)
4921 		goto errlo;
4922 
4923 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
4924 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
4925 
4926 	register_netdevice_notifier(&ipv6_dev_notf);
4927 
4928 	addrconf_verify(0);
4929 
4930 	err = rtnl_af_register(&inet6_ops);
4931 	if (err < 0)
4932 		goto errout_af;
4933 
4934 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
4935 			      NULL);
4936 	if (err < 0)
4937 		goto errout;
4938 
4939 	/* Only the first call to __rtnl_register can fail */
4940 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, NULL);
4941 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, NULL);
4942 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
4943 			inet6_dump_ifaddr, NULL);
4944 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
4945 			inet6_dump_ifmcaddr, NULL);
4946 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
4947 			inet6_dump_ifacaddr, NULL);
4948 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
4949 			NULL, NULL);
4950 
4951 	ipv6_addr_label_rtnl_register();
4952 
4953 	return 0;
4954 errout:
4955 	rtnl_af_unregister(&inet6_ops);
4956 errout_af:
4957 	unregister_netdevice_notifier(&ipv6_dev_notf);
4958 errlo:
4959 	unregister_pernet_subsys(&addrconf_ops);
4960 out_addrlabel:
4961 	ipv6_addr_label_cleanup();
4962 out:
4963 	return err;
4964 }
4965 
4966 void addrconf_cleanup(void)
4967 {
4968 	struct net_device *dev;
4969 	int i;
4970 
4971 	unregister_netdevice_notifier(&ipv6_dev_notf);
4972 	unregister_pernet_subsys(&addrconf_ops);
4973 	ipv6_addr_label_cleanup();
4974 
4975 	rtnl_lock();
4976 
4977 	__rtnl_af_unregister(&inet6_ops);
4978 
4979 	/* clean dev list */
4980 	for_each_netdev(&init_net, dev) {
4981 		if (__in6_dev_get(dev) == NULL)
4982 			continue;
4983 		addrconf_ifdown(dev, 1);
4984 	}
4985 	addrconf_ifdown(init_net.loopback_dev, 2);
4986 
4987 	/*
4988 	 *	Check hash table.
4989 	 */
4990 	spin_lock_bh(&addrconf_hash_lock);
4991 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
4992 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
4993 	spin_unlock_bh(&addrconf_hash_lock);
4994 
4995 	del_timer(&addr_chk_timer);
4996 	rtnl_unlock();
4997 }
4998