xref: /openbmc/linux/net/ipv6/addrconf.c (revision 8684014d)
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/firewire.h>
74 #include <net/ipv6.h>
75 #include <net/protocol.h>
76 #include <net/ndisc.h>
77 #include <net/ip6_route.h>
78 #include <net/addrconf.h>
79 #include <net/tcp.h>
80 #include <net/ip.h>
81 #include <net/netlink.h>
82 #include <net/pkt_sched.h>
83 #include <linux/if_tunnel.h>
84 #include <linux/rtnetlink.h>
85 #include <linux/netconf.h>
86 #include <linux/random.h>
87 #include <linux/uaccess.h>
88 #include <asm/unaligned.h>
89 
90 #include <linux/proc_fs.h>
91 #include <linux/seq_file.h>
92 #include <linux/export.h>
93 
94 /* Set to 3 to get tracing... */
95 #define ACONF_DEBUG 2
96 
97 #if ACONF_DEBUG >= 3
98 #define ADBG(fmt, ...) printk(fmt, ##__VA_ARGS__)
99 #else
100 #define ADBG(fmt, ...) do { if (0) printk(fmt, ##__VA_ARGS__); } while (0)
101 #endif
102 
103 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
104 
105 static inline u32 cstamp_delta(unsigned long cstamp)
106 {
107 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
108 }
109 
110 #ifdef CONFIG_SYSCTL
111 static int addrconf_sysctl_register(struct inet6_dev *idev);
112 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
113 #else
114 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
115 {
116 	return 0;
117 }
118 
119 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
120 {
121 }
122 #endif
123 
124 static void __ipv6_regen_rndid(struct inet6_dev *idev);
125 static void __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
126 static void ipv6_regen_rndid(unsigned long data);
127 
128 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
129 static int ipv6_count_addresses(struct inet6_dev *idev);
130 
131 /*
132  *	Configured unicast address hash table
133  */
134 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
135 static DEFINE_SPINLOCK(addrconf_hash_lock);
136 
137 static void addrconf_verify(void);
138 static void addrconf_verify_rtnl(void);
139 static void addrconf_verify_work(struct work_struct *);
140 
141 static struct workqueue_struct *addrconf_wq;
142 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
143 
144 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
145 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
146 
147 static void addrconf_type_change(struct net_device *dev,
148 				 unsigned long event);
149 static int addrconf_ifdown(struct net_device *dev, int how);
150 
151 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
152 						  int plen,
153 						  const struct net_device *dev,
154 						  u32 flags, u32 noflags);
155 
156 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
157 static void addrconf_dad_work(struct work_struct *w);
158 static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
159 static void addrconf_dad_run(struct inet6_dev *idev);
160 static void addrconf_rs_timer(unsigned long data);
161 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
162 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
163 
164 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
165 				struct prefix_info *pinfo);
166 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
167 			       struct net_device *dev);
168 
169 static struct ipv6_devconf ipv6_devconf __read_mostly = {
170 	.forwarding		= 0,
171 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
172 	.mtu6			= IPV6_MIN_MTU,
173 	.accept_ra		= 1,
174 	.accept_redirects	= 1,
175 	.autoconf		= 1,
176 	.force_mld_version	= 0,
177 	.mldv1_unsolicited_report_interval = 10 * HZ,
178 	.mldv2_unsolicited_report_interval = HZ,
179 	.dad_transmits		= 1,
180 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
181 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
182 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
183 	.use_tempaddr		= 0,
184 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
185 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
186 	.regen_max_retry	= REGEN_MAX_RETRY,
187 	.max_desync_factor	= MAX_DESYNC_FACTOR,
188 	.max_addresses		= IPV6_MAX_ADDRESSES,
189 	.accept_ra_defrtr	= 1,
190 	.accept_ra_from_local	= 0,
191 	.accept_ra_pinfo	= 1,
192 #ifdef CONFIG_IPV6_ROUTER_PREF
193 	.accept_ra_rtr_pref	= 1,
194 	.rtr_probe_interval	= 60 * HZ,
195 #ifdef CONFIG_IPV6_ROUTE_INFO
196 	.accept_ra_rt_info_max_plen = 0,
197 #endif
198 #endif
199 	.proxy_ndp		= 0,
200 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
201 	.disable_ipv6		= 0,
202 	.accept_dad		= 1,
203 	.suppress_frag_ndisc	= 1,
204 };
205 
206 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
207 	.forwarding		= 0,
208 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
209 	.mtu6			= IPV6_MIN_MTU,
210 	.accept_ra		= 1,
211 	.accept_redirects	= 1,
212 	.autoconf		= 1,
213 	.force_mld_version	= 0,
214 	.mldv1_unsolicited_report_interval = 10 * HZ,
215 	.mldv2_unsolicited_report_interval = HZ,
216 	.dad_transmits		= 1,
217 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
218 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
219 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
220 	.use_tempaddr		= 0,
221 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
222 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
223 	.regen_max_retry	= REGEN_MAX_RETRY,
224 	.max_desync_factor	= MAX_DESYNC_FACTOR,
225 	.max_addresses		= IPV6_MAX_ADDRESSES,
226 	.accept_ra_defrtr	= 1,
227 	.accept_ra_from_local	= 0,
228 	.accept_ra_pinfo	= 1,
229 #ifdef CONFIG_IPV6_ROUTER_PREF
230 	.accept_ra_rtr_pref	= 1,
231 	.rtr_probe_interval	= 60 * HZ,
232 #ifdef CONFIG_IPV6_ROUTE_INFO
233 	.accept_ra_rt_info_max_plen = 0,
234 #endif
235 #endif
236 	.proxy_ndp		= 0,
237 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
238 	.disable_ipv6		= 0,
239 	.accept_dad		= 1,
240 	.suppress_frag_ndisc	= 1,
241 };
242 
243 /* Check if a valid qdisc is available */
244 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
245 {
246 	return !qdisc_tx_is_noop(dev);
247 }
248 
249 static void addrconf_del_rs_timer(struct inet6_dev *idev)
250 {
251 	if (del_timer(&idev->rs_timer))
252 		__in6_dev_put(idev);
253 }
254 
255 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
256 {
257 	if (cancel_delayed_work(&ifp->dad_work))
258 		__in6_ifa_put(ifp);
259 }
260 
261 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
262 				  unsigned long when)
263 {
264 	if (!timer_pending(&idev->rs_timer))
265 		in6_dev_hold(idev);
266 	mod_timer(&idev->rs_timer, jiffies + when);
267 }
268 
269 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
270 				   unsigned long delay)
271 {
272 	if (!delayed_work_pending(&ifp->dad_work))
273 		in6_ifa_hold(ifp);
274 	mod_delayed_work(addrconf_wq, &ifp->dad_work, delay);
275 }
276 
277 static int snmp6_alloc_dev(struct inet6_dev *idev)
278 {
279 	int i;
280 
281 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
282 	if (!idev->stats.ipv6)
283 		goto err_ip;
284 
285 	for_each_possible_cpu(i) {
286 		struct ipstats_mib *addrconf_stats;
287 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
288 		u64_stats_init(&addrconf_stats->syncp);
289 	}
290 
291 
292 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
293 					GFP_KERNEL);
294 	if (!idev->stats.icmpv6dev)
295 		goto err_icmp;
296 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
297 					   GFP_KERNEL);
298 	if (!idev->stats.icmpv6msgdev)
299 		goto err_icmpmsg;
300 
301 	return 0;
302 
303 err_icmpmsg:
304 	kfree(idev->stats.icmpv6dev);
305 err_icmp:
306 	free_percpu(idev->stats.ipv6);
307 err_ip:
308 	return -ENOMEM;
309 }
310 
311 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
312 {
313 	struct inet6_dev *ndev;
314 	int err = -ENOMEM;
315 
316 	ASSERT_RTNL();
317 
318 	if (dev->mtu < IPV6_MIN_MTU)
319 		return ERR_PTR(-EINVAL);
320 
321 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
322 	if (ndev == NULL)
323 		return ERR_PTR(err);
324 
325 	rwlock_init(&ndev->lock);
326 	ndev->dev = dev;
327 	INIT_LIST_HEAD(&ndev->addr_list);
328 	setup_timer(&ndev->rs_timer, addrconf_rs_timer,
329 		    (unsigned long)ndev);
330 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
331 	ndev->cnf.mtu6 = dev->mtu;
332 	ndev->cnf.sysctl = NULL;
333 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
334 	if (ndev->nd_parms == NULL) {
335 		kfree(ndev);
336 		return ERR_PTR(err);
337 	}
338 	if (ndev->cnf.forwarding)
339 		dev_disable_lro(dev);
340 	/* We refer to the device */
341 	dev_hold(dev);
342 
343 	if (snmp6_alloc_dev(ndev) < 0) {
344 		ADBG(KERN_WARNING
345 			"%s: cannot allocate memory for statistics; dev=%s.\n",
346 			__func__, dev->name);
347 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
348 		dev_put(dev);
349 		kfree(ndev);
350 		return ERR_PTR(err);
351 	}
352 
353 	if (snmp6_register_dev(ndev) < 0) {
354 		ADBG(KERN_WARNING
355 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
356 			__func__, dev->name);
357 		goto err_release;
358 	}
359 
360 	/* One reference from device.  We must do this before
361 	 * we invoke __ipv6_regen_rndid().
362 	 */
363 	in6_dev_hold(ndev);
364 
365 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
366 		ndev->cnf.accept_dad = -1;
367 
368 #if IS_ENABLED(CONFIG_IPV6_SIT)
369 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
370 		pr_info("%s: Disabled Multicast RS\n", dev->name);
371 		ndev->cnf.rtr_solicits = 0;
372 	}
373 #endif
374 
375 	INIT_LIST_HEAD(&ndev->tempaddr_list);
376 	setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
377 	if ((dev->flags&IFF_LOOPBACK) ||
378 	    dev->type == ARPHRD_TUNNEL ||
379 	    dev->type == ARPHRD_TUNNEL6 ||
380 	    dev->type == ARPHRD_SIT ||
381 	    dev->type == ARPHRD_NONE) {
382 		ndev->cnf.use_tempaddr = -1;
383 	} else {
384 		in6_dev_hold(ndev);
385 		ipv6_regen_rndid((unsigned long) ndev);
386 	}
387 
388 	ndev->token = in6addr_any;
389 
390 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
391 		ndev->if_flags |= IF_READY;
392 
393 	ipv6_mc_init_dev(ndev);
394 	ndev->tstamp = jiffies;
395 	err = addrconf_sysctl_register(ndev);
396 	if (err) {
397 		ipv6_mc_destroy_dev(ndev);
398 		del_timer(&ndev->regen_timer);
399 		goto err_release;
400 	}
401 	/* protected by rtnl_lock */
402 	rcu_assign_pointer(dev->ip6_ptr, ndev);
403 
404 	/* Join interface-local all-node multicast group */
405 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
406 
407 	/* Join all-node multicast group */
408 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
409 
410 	/* Join all-router multicast group if forwarding is set */
411 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
412 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
413 
414 	return ndev;
415 
416 err_release:
417 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
418 	ndev->dead = 1;
419 	in6_dev_finish_destroy(ndev);
420 	return ERR_PTR(err);
421 }
422 
423 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
424 {
425 	struct inet6_dev *idev;
426 
427 	ASSERT_RTNL();
428 
429 	idev = __in6_dev_get(dev);
430 	if (!idev) {
431 		idev = ipv6_add_dev(dev);
432 		if (IS_ERR(idev))
433 			return NULL;
434 	}
435 
436 	if (dev->flags&IFF_UP)
437 		ipv6_mc_up(idev);
438 	return idev;
439 }
440 
441 static int inet6_netconf_msgsize_devconf(int type)
442 {
443 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
444 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
445 
446 	/* type -1 is used for ALL */
447 	if (type == -1 || type == NETCONFA_FORWARDING)
448 		size += nla_total_size(4);
449 #ifdef CONFIG_IPV6_MROUTE
450 	if (type == -1 || type == NETCONFA_MC_FORWARDING)
451 		size += nla_total_size(4);
452 #endif
453 	if (type == -1 || type == NETCONFA_PROXY_NEIGH)
454 		size += nla_total_size(4);
455 
456 	return size;
457 }
458 
459 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
460 				      struct ipv6_devconf *devconf, u32 portid,
461 				      u32 seq, int event, unsigned int flags,
462 				      int type)
463 {
464 	struct nlmsghdr  *nlh;
465 	struct netconfmsg *ncm;
466 
467 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
468 			flags);
469 	if (nlh == NULL)
470 		return -EMSGSIZE;
471 
472 	ncm = nlmsg_data(nlh);
473 	ncm->ncm_family = AF_INET6;
474 
475 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
476 		goto nla_put_failure;
477 
478 	/* type -1 is used for ALL */
479 	if ((type == -1 || type == NETCONFA_FORWARDING) &&
480 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
481 		goto nla_put_failure;
482 #ifdef CONFIG_IPV6_MROUTE
483 	if ((type == -1 || type == NETCONFA_MC_FORWARDING) &&
484 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
485 			devconf->mc_forwarding) < 0)
486 		goto nla_put_failure;
487 #endif
488 	if ((type == -1 || type == NETCONFA_PROXY_NEIGH) &&
489 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
490 		goto nla_put_failure;
491 
492 	return nlmsg_end(skb, nlh);
493 
494 nla_put_failure:
495 	nlmsg_cancel(skb, nlh);
496 	return -EMSGSIZE;
497 }
498 
499 void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
500 				  struct ipv6_devconf *devconf)
501 {
502 	struct sk_buff *skb;
503 	int err = -ENOBUFS;
504 
505 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_ATOMIC);
506 	if (skb == NULL)
507 		goto errout;
508 
509 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
510 					 RTM_NEWNETCONF, 0, type);
511 	if (err < 0) {
512 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
513 		WARN_ON(err == -EMSGSIZE);
514 		kfree_skb(skb);
515 		goto errout;
516 	}
517 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_ATOMIC);
518 	return;
519 errout:
520 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
521 }
522 
523 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
524 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
525 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
526 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
527 };
528 
529 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
530 				     struct nlmsghdr *nlh)
531 {
532 	struct net *net = sock_net(in_skb->sk);
533 	struct nlattr *tb[NETCONFA_MAX+1];
534 	struct netconfmsg *ncm;
535 	struct sk_buff *skb;
536 	struct ipv6_devconf *devconf;
537 	struct inet6_dev *in6_dev;
538 	struct net_device *dev;
539 	int ifindex;
540 	int err;
541 
542 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
543 			  devconf_ipv6_policy);
544 	if (err < 0)
545 		goto errout;
546 
547 	err = EINVAL;
548 	if (!tb[NETCONFA_IFINDEX])
549 		goto errout;
550 
551 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
552 	switch (ifindex) {
553 	case NETCONFA_IFINDEX_ALL:
554 		devconf = net->ipv6.devconf_all;
555 		break;
556 	case NETCONFA_IFINDEX_DEFAULT:
557 		devconf = net->ipv6.devconf_dflt;
558 		break;
559 	default:
560 		dev = __dev_get_by_index(net, ifindex);
561 		if (dev == NULL)
562 			goto errout;
563 		in6_dev = __in6_dev_get(dev);
564 		if (in6_dev == NULL)
565 			goto errout;
566 		devconf = &in6_dev->cnf;
567 		break;
568 	}
569 
570 	err = -ENOBUFS;
571 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(-1), GFP_ATOMIC);
572 	if (skb == NULL)
573 		goto errout;
574 
575 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
576 					 NETLINK_CB(in_skb).portid,
577 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
578 					 -1);
579 	if (err < 0) {
580 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
581 		WARN_ON(err == -EMSGSIZE);
582 		kfree_skb(skb);
583 		goto errout;
584 	}
585 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
586 errout:
587 	return err;
588 }
589 
590 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
591 				      struct netlink_callback *cb)
592 {
593 	struct net *net = sock_net(skb->sk);
594 	int h, s_h;
595 	int idx, s_idx;
596 	struct net_device *dev;
597 	struct inet6_dev *idev;
598 	struct hlist_head *head;
599 
600 	s_h = cb->args[0];
601 	s_idx = idx = cb->args[1];
602 
603 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
604 		idx = 0;
605 		head = &net->dev_index_head[h];
606 		rcu_read_lock();
607 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
608 			  net->dev_base_seq;
609 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
610 			if (idx < s_idx)
611 				goto cont;
612 			idev = __in6_dev_get(dev);
613 			if (!idev)
614 				goto cont;
615 
616 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
617 						       &idev->cnf,
618 						       NETLINK_CB(cb->skb).portid,
619 						       cb->nlh->nlmsg_seq,
620 						       RTM_NEWNETCONF,
621 						       NLM_F_MULTI,
622 						       -1) <= 0) {
623 				rcu_read_unlock();
624 				goto done;
625 			}
626 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
627 cont:
628 			idx++;
629 		}
630 		rcu_read_unlock();
631 	}
632 	if (h == NETDEV_HASHENTRIES) {
633 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
634 					       net->ipv6.devconf_all,
635 					       NETLINK_CB(cb->skb).portid,
636 					       cb->nlh->nlmsg_seq,
637 					       RTM_NEWNETCONF, NLM_F_MULTI,
638 					       -1) <= 0)
639 			goto done;
640 		else
641 			h++;
642 	}
643 	if (h == NETDEV_HASHENTRIES + 1) {
644 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
645 					       net->ipv6.devconf_dflt,
646 					       NETLINK_CB(cb->skb).portid,
647 					       cb->nlh->nlmsg_seq,
648 					       RTM_NEWNETCONF, NLM_F_MULTI,
649 					       -1) <= 0)
650 			goto done;
651 		else
652 			h++;
653 	}
654 done:
655 	cb->args[0] = h;
656 	cb->args[1] = idx;
657 
658 	return skb->len;
659 }
660 
661 #ifdef CONFIG_SYSCTL
662 static void dev_forward_change(struct inet6_dev *idev)
663 {
664 	struct net_device *dev;
665 	struct inet6_ifaddr *ifa;
666 
667 	if (!idev)
668 		return;
669 	dev = idev->dev;
670 	if (idev->cnf.forwarding)
671 		dev_disable_lro(dev);
672 	if (dev->flags & IFF_MULTICAST) {
673 		if (idev->cnf.forwarding) {
674 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
675 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
676 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
677 		} else {
678 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
679 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
680 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
681 		}
682 	}
683 
684 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
685 		if (ifa->flags&IFA_F_TENTATIVE)
686 			continue;
687 		if (idev->cnf.forwarding)
688 			addrconf_join_anycast(ifa);
689 		else
690 			addrconf_leave_anycast(ifa);
691 	}
692 	inet6_netconf_notify_devconf(dev_net(dev), NETCONFA_FORWARDING,
693 				     dev->ifindex, &idev->cnf);
694 }
695 
696 
697 static void addrconf_forward_change(struct net *net, __s32 newf)
698 {
699 	struct net_device *dev;
700 	struct inet6_dev *idev;
701 
702 	for_each_netdev(net, dev) {
703 		idev = __in6_dev_get(dev);
704 		if (idev) {
705 			int changed = (!idev->cnf.forwarding) ^ (!newf);
706 			idev->cnf.forwarding = newf;
707 			if (changed)
708 				dev_forward_change(idev);
709 		}
710 	}
711 }
712 
713 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
714 {
715 	struct net *net;
716 	int old;
717 
718 	if (!rtnl_trylock())
719 		return restart_syscall();
720 
721 	net = (struct net *)table->extra2;
722 	old = *p;
723 	*p = newf;
724 
725 	if (p == &net->ipv6.devconf_dflt->forwarding) {
726 		if ((!newf) ^ (!old))
727 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
728 						     NETCONFA_IFINDEX_DEFAULT,
729 						     net->ipv6.devconf_dflt);
730 		rtnl_unlock();
731 		return 0;
732 	}
733 
734 	if (p == &net->ipv6.devconf_all->forwarding) {
735 		net->ipv6.devconf_dflt->forwarding = newf;
736 		addrconf_forward_change(net, newf);
737 		if ((!newf) ^ (!old))
738 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
739 						     NETCONFA_IFINDEX_ALL,
740 						     net->ipv6.devconf_all);
741 	} else if ((!newf) ^ (!old))
742 		dev_forward_change((struct inet6_dev *)table->extra1);
743 	rtnl_unlock();
744 
745 	if (newf)
746 		rt6_purge_dflt_routers(net);
747 	return 1;
748 }
749 #endif
750 
751 /* Nobody refers to this ifaddr, destroy it */
752 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
753 {
754 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
755 
756 #ifdef NET_REFCNT_DEBUG
757 	pr_debug("%s\n", __func__);
758 #endif
759 
760 	in6_dev_put(ifp->idev);
761 
762 	if (cancel_delayed_work(&ifp->dad_work))
763 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
764 			  ifp);
765 
766 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
767 		pr_warn("Freeing alive inet6 address %p\n", ifp);
768 		return;
769 	}
770 	ip6_rt_put(ifp->rt);
771 
772 	kfree_rcu(ifp, rcu);
773 }
774 
775 static void
776 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
777 {
778 	struct list_head *p;
779 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
780 
781 	/*
782 	 * Each device address list is sorted in order of scope -
783 	 * global before linklocal.
784 	 */
785 	list_for_each(p, &idev->addr_list) {
786 		struct inet6_ifaddr *ifa
787 			= list_entry(p, struct inet6_ifaddr, if_list);
788 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
789 			break;
790 	}
791 
792 	list_add_tail(&ifp->if_list, p);
793 }
794 
795 static u32 inet6_addr_hash(const struct in6_addr *addr)
796 {
797 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
798 }
799 
800 /* On success it returns ifp with increased reference count */
801 
802 static struct inet6_ifaddr *
803 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
804 	      const struct in6_addr *peer_addr, int pfxlen,
805 	      int scope, u32 flags, u32 valid_lft, u32 prefered_lft)
806 {
807 	struct inet6_ifaddr *ifa = NULL;
808 	struct rt6_info *rt;
809 	unsigned int hash;
810 	int err = 0;
811 	int addr_type = ipv6_addr_type(addr);
812 
813 	if (addr_type == IPV6_ADDR_ANY ||
814 	    addr_type & IPV6_ADDR_MULTICAST ||
815 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
816 	     addr_type & IPV6_ADDR_LOOPBACK))
817 		return ERR_PTR(-EADDRNOTAVAIL);
818 
819 	rcu_read_lock_bh();
820 	if (idev->dead) {
821 		err = -ENODEV;			/*XXX*/
822 		goto out2;
823 	}
824 
825 	if (idev->cnf.disable_ipv6) {
826 		err = -EACCES;
827 		goto out2;
828 	}
829 
830 	spin_lock(&addrconf_hash_lock);
831 
832 	/* Ignore adding duplicate addresses on an interface */
833 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
834 		ADBG("ipv6_add_addr: already assigned\n");
835 		err = -EEXIST;
836 		goto out;
837 	}
838 
839 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
840 
841 	if (ifa == NULL) {
842 		ADBG("ipv6_add_addr: malloc failed\n");
843 		err = -ENOBUFS;
844 		goto out;
845 	}
846 
847 	rt = addrconf_dst_alloc(idev, addr, false);
848 	if (IS_ERR(rt)) {
849 		err = PTR_ERR(rt);
850 		goto out;
851 	}
852 
853 	neigh_parms_data_state_setall(idev->nd_parms);
854 
855 	ifa->addr = *addr;
856 	if (peer_addr)
857 		ifa->peer_addr = *peer_addr;
858 
859 	spin_lock_init(&ifa->lock);
860 	spin_lock_init(&ifa->state_lock);
861 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
862 	INIT_HLIST_NODE(&ifa->addr_lst);
863 	ifa->scope = scope;
864 	ifa->prefix_len = pfxlen;
865 	ifa->flags = flags | IFA_F_TENTATIVE;
866 	ifa->valid_lft = valid_lft;
867 	ifa->prefered_lft = prefered_lft;
868 	ifa->cstamp = ifa->tstamp = jiffies;
869 	ifa->tokenized = false;
870 
871 	ifa->rt = rt;
872 
873 	ifa->idev = idev;
874 	in6_dev_hold(idev);
875 	/* For caller */
876 	in6_ifa_hold(ifa);
877 
878 	/* Add to big hash table */
879 	hash = inet6_addr_hash(addr);
880 
881 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
882 	spin_unlock(&addrconf_hash_lock);
883 
884 	write_lock(&idev->lock);
885 	/* Add to inet6_dev unicast addr list. */
886 	ipv6_link_dev_addr(idev, ifa);
887 
888 	if (ifa->flags&IFA_F_TEMPORARY) {
889 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
890 		in6_ifa_hold(ifa);
891 	}
892 
893 	in6_ifa_hold(ifa);
894 	write_unlock(&idev->lock);
895 out2:
896 	rcu_read_unlock_bh();
897 
898 	if (likely(err == 0))
899 		inet6addr_notifier_call_chain(NETDEV_UP, ifa);
900 	else {
901 		kfree(ifa);
902 		ifa = ERR_PTR(err);
903 	}
904 
905 	return ifa;
906 out:
907 	spin_unlock(&addrconf_hash_lock);
908 	goto out2;
909 }
910 
911 enum cleanup_prefix_rt_t {
912 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
913 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
914 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
915 };
916 
917 /*
918  * Check, whether the prefix for ifp would still need a prefix route
919  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
920  * constants.
921  *
922  * 1) we don't purge prefix if address was not permanent.
923  *    prefix is managed by its own lifetime.
924  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
925  * 3) if there are no addresses, delete prefix.
926  * 4) if there are still other permanent address(es),
927  *    corresponding prefix is still permanent.
928  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
929  *    don't purge the prefix, assume user space is managing it.
930  * 6) otherwise, update prefix lifetime to the
931  *    longest valid lifetime among the corresponding
932  *    addresses on the device.
933  *    Note: subsequent RA will update lifetime.
934  **/
935 static enum cleanup_prefix_rt_t
936 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
937 {
938 	struct inet6_ifaddr *ifa;
939 	struct inet6_dev *idev = ifp->idev;
940 	unsigned long lifetime;
941 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
942 
943 	*expires = jiffies;
944 
945 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
946 		if (ifa == ifp)
947 			continue;
948 		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
949 				       ifp->prefix_len))
950 			continue;
951 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
952 			return CLEANUP_PREFIX_RT_NOP;
953 
954 		action = CLEANUP_PREFIX_RT_EXPIRE;
955 
956 		spin_lock(&ifa->lock);
957 
958 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
959 		/*
960 		 * Note: Because this address is
961 		 * not permanent, lifetime <
962 		 * LONG_MAX / HZ here.
963 		 */
964 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
965 			*expires = ifa->tstamp + lifetime * HZ;
966 		spin_unlock(&ifa->lock);
967 	}
968 
969 	return action;
970 }
971 
972 static void
973 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
974 {
975 	struct rt6_info *rt;
976 
977 	rt = addrconf_get_prefix_route(&ifp->addr,
978 				       ifp->prefix_len,
979 				       ifp->idev->dev,
980 				       0, RTF_GATEWAY | RTF_DEFAULT);
981 	if (rt) {
982 		if (del_rt)
983 			ip6_del_rt(rt);
984 		else {
985 			if (!(rt->rt6i_flags & RTF_EXPIRES))
986 				rt6_set_expires(rt, expires);
987 			ip6_rt_put(rt);
988 		}
989 	}
990 }
991 
992 
993 /* This function wants to get referenced ifp and releases it before return */
994 
995 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
996 {
997 	int state;
998 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
999 	unsigned long expires;
1000 
1001 	ASSERT_RTNL();
1002 
1003 	spin_lock_bh(&ifp->state_lock);
1004 	state = ifp->state;
1005 	ifp->state = INET6_IFADDR_STATE_DEAD;
1006 	spin_unlock_bh(&ifp->state_lock);
1007 
1008 	if (state == INET6_IFADDR_STATE_DEAD)
1009 		goto out;
1010 
1011 	spin_lock_bh(&addrconf_hash_lock);
1012 	hlist_del_init_rcu(&ifp->addr_lst);
1013 	spin_unlock_bh(&addrconf_hash_lock);
1014 
1015 	write_lock_bh(&ifp->idev->lock);
1016 
1017 	if (ifp->flags&IFA_F_TEMPORARY) {
1018 		list_del(&ifp->tmp_list);
1019 		if (ifp->ifpub) {
1020 			in6_ifa_put(ifp->ifpub);
1021 			ifp->ifpub = NULL;
1022 		}
1023 		__in6_ifa_put(ifp);
1024 	}
1025 
1026 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1027 		action = check_cleanup_prefix_route(ifp, &expires);
1028 
1029 	list_del_init(&ifp->if_list);
1030 	__in6_ifa_put(ifp);
1031 
1032 	write_unlock_bh(&ifp->idev->lock);
1033 
1034 	addrconf_del_dad_work(ifp);
1035 
1036 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1037 
1038 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1039 
1040 	if (action != CLEANUP_PREFIX_RT_NOP) {
1041 		cleanup_prefix_route(ifp, expires,
1042 			action == CLEANUP_PREFIX_RT_DEL);
1043 	}
1044 
1045 	/* clean up prefsrc entries */
1046 	rt6_remove_prefsrc(ifp);
1047 out:
1048 	in6_ifa_put(ifp);
1049 }
1050 
1051 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
1052 {
1053 	struct inet6_dev *idev = ifp->idev;
1054 	struct in6_addr addr, *tmpaddr;
1055 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
1056 	unsigned long regen_advance;
1057 	int tmp_plen;
1058 	int ret = 0;
1059 	u32 addr_flags;
1060 	unsigned long now = jiffies;
1061 
1062 	write_lock_bh(&idev->lock);
1063 	if (ift) {
1064 		spin_lock_bh(&ift->lock);
1065 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1066 		spin_unlock_bh(&ift->lock);
1067 		tmpaddr = &addr;
1068 	} else {
1069 		tmpaddr = NULL;
1070 	}
1071 retry:
1072 	in6_dev_hold(idev);
1073 	if (idev->cnf.use_tempaddr <= 0) {
1074 		write_unlock_bh(&idev->lock);
1075 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1076 		in6_dev_put(idev);
1077 		ret = -1;
1078 		goto out;
1079 	}
1080 	spin_lock_bh(&ifp->lock);
1081 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1082 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1083 		spin_unlock_bh(&ifp->lock);
1084 		write_unlock_bh(&idev->lock);
1085 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1086 			__func__);
1087 		in6_dev_put(idev);
1088 		ret = -1;
1089 		goto out;
1090 	}
1091 	in6_ifa_hold(ifp);
1092 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1093 	__ipv6_try_regen_rndid(idev, tmpaddr);
1094 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1095 	age = (now - ifp->tstamp) / HZ;
1096 	tmp_valid_lft = min_t(__u32,
1097 			      ifp->valid_lft,
1098 			      idev->cnf.temp_valid_lft + age);
1099 	tmp_prefered_lft = min_t(__u32,
1100 				 ifp->prefered_lft,
1101 				 idev->cnf.temp_prefered_lft + age -
1102 				 idev->cnf.max_desync_factor);
1103 	tmp_plen = ifp->prefix_len;
1104 	tmp_tstamp = ifp->tstamp;
1105 	spin_unlock_bh(&ifp->lock);
1106 
1107 	regen_advance = idev->cnf.regen_max_retry *
1108 			idev->cnf.dad_transmits *
1109 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1110 	write_unlock_bh(&idev->lock);
1111 
1112 	/* A temporary address is created only if this calculated Preferred
1113 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1114 	 * an implementation must not create a temporary address with a zero
1115 	 * Preferred Lifetime.
1116 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1117 	 * temporary addresses being generated.
1118 	 */
1119 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1120 	if (tmp_prefered_lft <= regen_advance + age) {
1121 		in6_ifa_put(ifp);
1122 		in6_dev_put(idev);
1123 		ret = -1;
1124 		goto out;
1125 	}
1126 
1127 	addr_flags = IFA_F_TEMPORARY;
1128 	/* set in addrconf_prefix_rcv() */
1129 	if (ifp->flags & IFA_F_OPTIMISTIC)
1130 		addr_flags |= IFA_F_OPTIMISTIC;
1131 
1132 	ift = ipv6_add_addr(idev, &addr, NULL, tmp_plen,
1133 			    ipv6_addr_scope(&addr), addr_flags,
1134 			    tmp_valid_lft, tmp_prefered_lft);
1135 	if (IS_ERR(ift)) {
1136 		in6_ifa_put(ifp);
1137 		in6_dev_put(idev);
1138 		pr_info("%s: retry temporary address regeneration\n", __func__);
1139 		tmpaddr = &addr;
1140 		write_lock_bh(&idev->lock);
1141 		goto retry;
1142 	}
1143 
1144 	spin_lock_bh(&ift->lock);
1145 	ift->ifpub = ifp;
1146 	ift->cstamp = now;
1147 	ift->tstamp = tmp_tstamp;
1148 	spin_unlock_bh(&ift->lock);
1149 
1150 	addrconf_dad_start(ift);
1151 	in6_ifa_put(ift);
1152 	in6_dev_put(idev);
1153 out:
1154 	return ret;
1155 }
1156 
1157 /*
1158  *	Choose an appropriate source address (RFC3484)
1159  */
1160 enum {
1161 	IPV6_SADDR_RULE_INIT = 0,
1162 	IPV6_SADDR_RULE_LOCAL,
1163 	IPV6_SADDR_RULE_SCOPE,
1164 	IPV6_SADDR_RULE_PREFERRED,
1165 #ifdef CONFIG_IPV6_MIP6
1166 	IPV6_SADDR_RULE_HOA,
1167 #endif
1168 	IPV6_SADDR_RULE_OIF,
1169 	IPV6_SADDR_RULE_LABEL,
1170 	IPV6_SADDR_RULE_PRIVACY,
1171 	IPV6_SADDR_RULE_ORCHID,
1172 	IPV6_SADDR_RULE_PREFIX,
1173 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1174 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1175 #endif
1176 	IPV6_SADDR_RULE_MAX
1177 };
1178 
1179 struct ipv6_saddr_score {
1180 	int			rule;
1181 	int			addr_type;
1182 	struct inet6_ifaddr	*ifa;
1183 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1184 	int			scopedist;
1185 	int			matchlen;
1186 };
1187 
1188 struct ipv6_saddr_dst {
1189 	const struct in6_addr *addr;
1190 	int ifindex;
1191 	int scope;
1192 	int label;
1193 	unsigned int prefs;
1194 };
1195 
1196 static inline int ipv6_saddr_preferred(int type)
1197 {
1198 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1199 		return 1;
1200 	return 0;
1201 }
1202 
1203 static inline bool ipv6_use_optimistic_addr(struct inet6_dev *idev)
1204 {
1205 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1206 	return idev && idev->cnf.optimistic_dad && idev->cnf.use_optimistic;
1207 #else
1208 	return false;
1209 #endif
1210 }
1211 
1212 static int ipv6_get_saddr_eval(struct net *net,
1213 			       struct ipv6_saddr_score *score,
1214 			       struct ipv6_saddr_dst *dst,
1215 			       int i)
1216 {
1217 	int ret;
1218 
1219 	if (i <= score->rule) {
1220 		switch (i) {
1221 		case IPV6_SADDR_RULE_SCOPE:
1222 			ret = score->scopedist;
1223 			break;
1224 		case IPV6_SADDR_RULE_PREFIX:
1225 			ret = score->matchlen;
1226 			break;
1227 		default:
1228 			ret = !!test_bit(i, score->scorebits);
1229 		}
1230 		goto out;
1231 	}
1232 
1233 	switch (i) {
1234 	case IPV6_SADDR_RULE_INIT:
1235 		/* Rule 0: remember if hiscore is not ready yet */
1236 		ret = !!score->ifa;
1237 		break;
1238 	case IPV6_SADDR_RULE_LOCAL:
1239 		/* Rule 1: Prefer same address */
1240 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1241 		break;
1242 	case IPV6_SADDR_RULE_SCOPE:
1243 		/* Rule 2: Prefer appropriate scope
1244 		 *
1245 		 *      ret
1246 		 *       ^
1247 		 *    -1 |  d 15
1248 		 *    ---+--+-+---> scope
1249 		 *       |
1250 		 *       |             d is scope of the destination.
1251 		 *  B-d  |  \
1252 		 *       |   \      <- smaller scope is better if
1253 		 *  B-15 |    \        if scope is enough for destination.
1254 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1255 		 * d-C-1 | /
1256 		 *       |/         <- greater is better
1257 		 *   -C  /             if scope is not enough for destination.
1258 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1259 		 *
1260 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1261 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1262 		 * Assume B = 0 and we get C > 29.
1263 		 */
1264 		ret = __ipv6_addr_src_scope(score->addr_type);
1265 		if (ret >= dst->scope)
1266 			ret = -ret;
1267 		else
1268 			ret -= 128;	/* 30 is enough */
1269 		score->scopedist = ret;
1270 		break;
1271 	case IPV6_SADDR_RULE_PREFERRED:
1272 	    {
1273 		/* Rule 3: Avoid deprecated and optimistic addresses */
1274 		u8 avoid = IFA_F_DEPRECATED;
1275 
1276 		if (!ipv6_use_optimistic_addr(score->ifa->idev))
1277 			avoid |= IFA_F_OPTIMISTIC;
1278 		ret = ipv6_saddr_preferred(score->addr_type) ||
1279 		      !(score->ifa->flags & avoid);
1280 		break;
1281 	    }
1282 #ifdef CONFIG_IPV6_MIP6
1283 	case IPV6_SADDR_RULE_HOA:
1284 	    {
1285 		/* Rule 4: Prefer home address */
1286 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1287 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1288 		break;
1289 	    }
1290 #endif
1291 	case IPV6_SADDR_RULE_OIF:
1292 		/* Rule 5: Prefer outgoing interface */
1293 		ret = (!dst->ifindex ||
1294 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1295 		break;
1296 	case IPV6_SADDR_RULE_LABEL:
1297 		/* Rule 6: Prefer matching label */
1298 		ret = ipv6_addr_label(net,
1299 				      &score->ifa->addr, score->addr_type,
1300 				      score->ifa->idev->dev->ifindex) == dst->label;
1301 		break;
1302 	case IPV6_SADDR_RULE_PRIVACY:
1303 	    {
1304 		/* Rule 7: Prefer public address
1305 		 * Note: prefer temporary address if use_tempaddr >= 2
1306 		 */
1307 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1308 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1309 				score->ifa->idev->cnf.use_tempaddr >= 2;
1310 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1311 		break;
1312 	    }
1313 	case IPV6_SADDR_RULE_ORCHID:
1314 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1315 		 *	    non-ORCHID vs non-ORCHID
1316 		 */
1317 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1318 			ipv6_addr_orchid(dst->addr));
1319 		break;
1320 	case IPV6_SADDR_RULE_PREFIX:
1321 		/* Rule 8: Use longest matching prefix */
1322 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1323 		if (ret > score->ifa->prefix_len)
1324 			ret = score->ifa->prefix_len;
1325 		score->matchlen = ret;
1326 		break;
1327 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1328 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1329 		/* Optimistic addresses still have lower precedence than other
1330 		 * preferred addresses.
1331 		 */
1332 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1333 		break;
1334 #endif
1335 	default:
1336 		ret = 0;
1337 	}
1338 
1339 	if (ret)
1340 		__set_bit(i, score->scorebits);
1341 	score->rule = i;
1342 out:
1343 	return ret;
1344 }
1345 
1346 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1347 		       const struct in6_addr *daddr, unsigned int prefs,
1348 		       struct in6_addr *saddr)
1349 {
1350 	struct ipv6_saddr_score scores[2],
1351 				*score = &scores[0], *hiscore = &scores[1];
1352 	struct ipv6_saddr_dst dst;
1353 	struct net_device *dev;
1354 	int dst_type;
1355 
1356 	dst_type = __ipv6_addr_type(daddr);
1357 	dst.addr = daddr;
1358 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1359 	dst.scope = __ipv6_addr_src_scope(dst_type);
1360 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1361 	dst.prefs = prefs;
1362 
1363 	hiscore->rule = -1;
1364 	hiscore->ifa = NULL;
1365 
1366 	rcu_read_lock();
1367 
1368 	for_each_netdev_rcu(net, dev) {
1369 		struct inet6_dev *idev;
1370 
1371 		/* Candidate Source Address (section 4)
1372 		 *  - multicast and link-local destination address,
1373 		 *    the set of candidate source address MUST only
1374 		 *    include addresses assigned to interfaces
1375 		 *    belonging to the same link as the outgoing
1376 		 *    interface.
1377 		 * (- For site-local destination addresses, the
1378 		 *    set of candidate source addresses MUST only
1379 		 *    include addresses assigned to interfaces
1380 		 *    belonging to the same site as the outgoing
1381 		 *    interface.)
1382 		 */
1383 		if (((dst_type & IPV6_ADDR_MULTICAST) ||
1384 		     dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) &&
1385 		    dst.ifindex && dev->ifindex != dst.ifindex)
1386 			continue;
1387 
1388 		idev = __in6_dev_get(dev);
1389 		if (!idev)
1390 			continue;
1391 
1392 		read_lock_bh(&idev->lock);
1393 		list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1394 			int i;
1395 
1396 			/*
1397 			 * - Tentative Address (RFC2462 section 5.4)
1398 			 *  - A tentative address is not considered
1399 			 *    "assigned to an interface" in the traditional
1400 			 *    sense, unless it is also flagged as optimistic.
1401 			 * - Candidate Source Address (section 4)
1402 			 *  - In any case, anycast addresses, multicast
1403 			 *    addresses, and the unspecified address MUST
1404 			 *    NOT be included in a candidate set.
1405 			 */
1406 			if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1407 			    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1408 				continue;
1409 
1410 			score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1411 
1412 			if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1413 				     score->addr_type & IPV6_ADDR_MULTICAST)) {
1414 				net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1415 						    dev->name);
1416 				continue;
1417 			}
1418 
1419 			score->rule = -1;
1420 			bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1421 
1422 			for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1423 				int minihiscore, miniscore;
1424 
1425 				minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
1426 				miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
1427 
1428 				if (minihiscore > miniscore) {
1429 					if (i == IPV6_SADDR_RULE_SCOPE &&
1430 					    score->scopedist > 0) {
1431 						/*
1432 						 * special case:
1433 						 * each remaining entry
1434 						 * has too small (not enough)
1435 						 * scope, because ifa entries
1436 						 * are sorted by their scope
1437 						 * values.
1438 						 */
1439 						goto try_nextdev;
1440 					}
1441 					break;
1442 				} else if (minihiscore < miniscore) {
1443 					if (hiscore->ifa)
1444 						in6_ifa_put(hiscore->ifa);
1445 
1446 					in6_ifa_hold(score->ifa);
1447 
1448 					swap(hiscore, score);
1449 
1450 					/* restore our iterator */
1451 					score->ifa = hiscore->ifa;
1452 
1453 					break;
1454 				}
1455 			}
1456 		}
1457 try_nextdev:
1458 		read_unlock_bh(&idev->lock);
1459 	}
1460 	rcu_read_unlock();
1461 
1462 	if (!hiscore->ifa)
1463 		return -EADDRNOTAVAIL;
1464 
1465 	*saddr = hiscore->ifa->addr;
1466 	in6_ifa_put(hiscore->ifa);
1467 	return 0;
1468 }
1469 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1470 
1471 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1472 		      u32 banned_flags)
1473 {
1474 	struct inet6_ifaddr *ifp;
1475 	int err = -EADDRNOTAVAIL;
1476 
1477 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1478 		if (ifp->scope > IFA_LINK)
1479 			break;
1480 		if (ifp->scope == IFA_LINK &&
1481 		    !(ifp->flags & banned_flags)) {
1482 			*addr = ifp->addr;
1483 			err = 0;
1484 			break;
1485 		}
1486 	}
1487 	return err;
1488 }
1489 
1490 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1491 		    u32 banned_flags)
1492 {
1493 	struct inet6_dev *idev;
1494 	int err = -EADDRNOTAVAIL;
1495 
1496 	rcu_read_lock();
1497 	idev = __in6_dev_get(dev);
1498 	if (idev) {
1499 		read_lock_bh(&idev->lock);
1500 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1501 		read_unlock_bh(&idev->lock);
1502 	}
1503 	rcu_read_unlock();
1504 	return err;
1505 }
1506 
1507 static int ipv6_count_addresses(struct inet6_dev *idev)
1508 {
1509 	int cnt = 0;
1510 	struct inet6_ifaddr *ifp;
1511 
1512 	read_lock_bh(&idev->lock);
1513 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1514 		cnt++;
1515 	read_unlock_bh(&idev->lock);
1516 	return cnt;
1517 }
1518 
1519 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1520 		  const struct net_device *dev, int strict)
1521 {
1522 	struct inet6_ifaddr *ifp;
1523 	unsigned int hash = inet6_addr_hash(addr);
1524 
1525 	rcu_read_lock_bh();
1526 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1527 		if (!net_eq(dev_net(ifp->idev->dev), net))
1528 			continue;
1529 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1530 		    !(ifp->flags&IFA_F_TENTATIVE) &&
1531 		    (dev == NULL || ifp->idev->dev == dev ||
1532 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1533 			rcu_read_unlock_bh();
1534 			return 1;
1535 		}
1536 	}
1537 
1538 	rcu_read_unlock_bh();
1539 	return 0;
1540 }
1541 EXPORT_SYMBOL(ipv6_chk_addr);
1542 
1543 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1544 			       struct net_device *dev)
1545 {
1546 	unsigned int hash = inet6_addr_hash(addr);
1547 	struct inet6_ifaddr *ifp;
1548 
1549 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1550 		if (!net_eq(dev_net(ifp->idev->dev), net))
1551 			continue;
1552 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1553 			if (dev == NULL || ifp->idev->dev == dev)
1554 				return true;
1555 		}
1556 	}
1557 	return false;
1558 }
1559 
1560 /* Compares an address/prefix_len with addresses on device @dev.
1561  * If one is found it returns true.
1562  */
1563 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1564 	const unsigned int prefix_len, struct net_device *dev)
1565 {
1566 	struct inet6_dev *idev;
1567 	struct inet6_ifaddr *ifa;
1568 	bool ret = false;
1569 
1570 	rcu_read_lock();
1571 	idev = __in6_dev_get(dev);
1572 	if (idev) {
1573 		read_lock_bh(&idev->lock);
1574 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1575 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1576 			if (ret)
1577 				break;
1578 		}
1579 		read_unlock_bh(&idev->lock);
1580 	}
1581 	rcu_read_unlock();
1582 
1583 	return ret;
1584 }
1585 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1586 
1587 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1588 {
1589 	struct inet6_dev *idev;
1590 	struct inet6_ifaddr *ifa;
1591 	int	onlink;
1592 
1593 	onlink = 0;
1594 	rcu_read_lock();
1595 	idev = __in6_dev_get(dev);
1596 	if (idev) {
1597 		read_lock_bh(&idev->lock);
1598 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1599 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1600 						   ifa->prefix_len);
1601 			if (onlink)
1602 				break;
1603 		}
1604 		read_unlock_bh(&idev->lock);
1605 	}
1606 	rcu_read_unlock();
1607 	return onlink;
1608 }
1609 EXPORT_SYMBOL(ipv6_chk_prefix);
1610 
1611 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1612 				     struct net_device *dev, int strict)
1613 {
1614 	struct inet6_ifaddr *ifp, *result = NULL;
1615 	unsigned int hash = inet6_addr_hash(addr);
1616 
1617 	rcu_read_lock_bh();
1618 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
1619 		if (!net_eq(dev_net(ifp->idev->dev), net))
1620 			continue;
1621 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1622 			if (dev == NULL || ifp->idev->dev == dev ||
1623 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1624 				result = ifp;
1625 				in6_ifa_hold(ifp);
1626 				break;
1627 			}
1628 		}
1629 	}
1630 	rcu_read_unlock_bh();
1631 
1632 	return result;
1633 }
1634 
1635 /* Gets referenced address, destroys ifaddr */
1636 
1637 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1638 {
1639 	if (ifp->flags&IFA_F_PERMANENT) {
1640 		spin_lock_bh(&ifp->lock);
1641 		addrconf_del_dad_work(ifp);
1642 		ifp->flags |= IFA_F_TENTATIVE;
1643 		if (dad_failed)
1644 			ifp->flags |= IFA_F_DADFAILED;
1645 		spin_unlock_bh(&ifp->lock);
1646 		if (dad_failed)
1647 			ipv6_ifa_notify(0, ifp);
1648 		in6_ifa_put(ifp);
1649 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1650 		struct inet6_ifaddr *ifpub;
1651 		spin_lock_bh(&ifp->lock);
1652 		ifpub = ifp->ifpub;
1653 		if (ifpub) {
1654 			in6_ifa_hold(ifpub);
1655 			spin_unlock_bh(&ifp->lock);
1656 			ipv6_create_tempaddr(ifpub, ifp);
1657 			in6_ifa_put(ifpub);
1658 		} else {
1659 			spin_unlock_bh(&ifp->lock);
1660 		}
1661 		ipv6_del_addr(ifp);
1662 	} else {
1663 		ipv6_del_addr(ifp);
1664 	}
1665 }
1666 
1667 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1668 {
1669 	int err = -ENOENT;
1670 
1671 	spin_lock_bh(&ifp->state_lock);
1672 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1673 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1674 		err = 0;
1675 	}
1676 	spin_unlock_bh(&ifp->state_lock);
1677 
1678 	return err;
1679 }
1680 
1681 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1682 {
1683 	struct inet6_dev *idev = ifp->idev;
1684 
1685 	if (addrconf_dad_end(ifp)) {
1686 		in6_ifa_put(ifp);
1687 		return;
1688 	}
1689 
1690 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1691 			     ifp->idev->dev->name, &ifp->addr);
1692 
1693 	if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1694 		struct in6_addr addr;
1695 
1696 		addr.s6_addr32[0] = htonl(0xfe800000);
1697 		addr.s6_addr32[1] = 0;
1698 
1699 		if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1700 		    ipv6_addr_equal(&ifp->addr, &addr)) {
1701 			/* DAD failed for link-local based on MAC address */
1702 			idev->cnf.disable_ipv6 = 1;
1703 
1704 			pr_info("%s: IPv6 being disabled!\n",
1705 				ifp->idev->dev->name);
1706 		}
1707 	}
1708 
1709 	spin_lock_bh(&ifp->state_lock);
1710 	/* transition from _POSTDAD to _ERRDAD */
1711 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
1712 	spin_unlock_bh(&ifp->state_lock);
1713 
1714 	addrconf_mod_dad_work(ifp, 0);
1715 }
1716 
1717 /* Join to solicited addr multicast group.
1718  * caller must hold RTNL */
1719 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
1720 {
1721 	struct in6_addr maddr;
1722 
1723 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1724 		return;
1725 
1726 	addrconf_addr_solict_mult(addr, &maddr);
1727 	ipv6_dev_mc_inc(dev, &maddr);
1728 }
1729 
1730 /* caller must hold RTNL */
1731 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
1732 {
1733 	struct in6_addr maddr;
1734 
1735 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1736 		return;
1737 
1738 	addrconf_addr_solict_mult(addr, &maddr);
1739 	__ipv6_dev_mc_dec(idev, &maddr);
1740 }
1741 
1742 /* caller must hold RTNL */
1743 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1744 {
1745 	struct in6_addr addr;
1746 
1747 	if (ifp->prefix_len >= 127) /* RFC 6164 */
1748 		return;
1749 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1750 	if (ipv6_addr_any(&addr))
1751 		return;
1752 	__ipv6_dev_ac_inc(ifp->idev, &addr);
1753 }
1754 
1755 /* caller must hold RTNL */
1756 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1757 {
1758 	struct in6_addr addr;
1759 
1760 	if (ifp->prefix_len >= 127) /* RFC 6164 */
1761 		return;
1762 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1763 	if (ipv6_addr_any(&addr))
1764 		return;
1765 	__ipv6_dev_ac_dec(ifp->idev, &addr);
1766 }
1767 
1768 static int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
1769 {
1770 	if (dev->addr_len != ETH_ALEN)
1771 		return -1;
1772 	memcpy(eui, dev->dev_addr, 3);
1773 	memcpy(eui + 5, dev->dev_addr + 3, 3);
1774 
1775 	/*
1776 	 * The zSeries OSA network cards can be shared among various
1777 	 * OS instances, but the OSA cards have only one MAC address.
1778 	 * This leads to duplicate address conflicts in conjunction
1779 	 * with IPv6 if more than one instance uses the same card.
1780 	 *
1781 	 * The driver for these cards can deliver a unique 16-bit
1782 	 * identifier for each instance sharing the same card.  It is
1783 	 * placed instead of 0xFFFE in the interface identifier.  The
1784 	 * "u" bit of the interface identifier is not inverted in this
1785 	 * case.  Hence the resulting interface identifier has local
1786 	 * scope according to RFC2373.
1787 	 */
1788 	if (dev->dev_id) {
1789 		eui[3] = (dev->dev_id >> 8) & 0xFF;
1790 		eui[4] = dev->dev_id & 0xFF;
1791 	} else {
1792 		eui[3] = 0xFF;
1793 		eui[4] = 0xFE;
1794 		eui[0] ^= 2;
1795 	}
1796 	return 0;
1797 }
1798 
1799 static int addrconf_ifid_eui64(u8 *eui, struct net_device *dev)
1800 {
1801 	if (dev->addr_len != IEEE802154_ADDR_LEN)
1802 		return -1;
1803 	memcpy(eui, dev->dev_addr, 8);
1804 	eui[0] ^= 2;
1805 	return 0;
1806 }
1807 
1808 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
1809 {
1810 	union fwnet_hwaddr *ha;
1811 
1812 	if (dev->addr_len != FWNET_ALEN)
1813 		return -1;
1814 
1815 	ha = (union fwnet_hwaddr *)dev->dev_addr;
1816 
1817 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
1818 	eui[0] ^= 2;
1819 	return 0;
1820 }
1821 
1822 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
1823 {
1824 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
1825 	if (dev->addr_len != ARCNET_ALEN)
1826 		return -1;
1827 	memset(eui, 0, 7);
1828 	eui[7] = *(u8 *)dev->dev_addr;
1829 	return 0;
1830 }
1831 
1832 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
1833 {
1834 	if (dev->addr_len != INFINIBAND_ALEN)
1835 		return -1;
1836 	memcpy(eui, dev->dev_addr + 12, 8);
1837 	eui[0] |= 2;
1838 	return 0;
1839 }
1840 
1841 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
1842 {
1843 	if (addr == 0)
1844 		return -1;
1845 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
1846 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
1847 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
1848 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
1849 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
1850 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
1851 	eui[1] = 0;
1852 	eui[2] = 0x5E;
1853 	eui[3] = 0xFE;
1854 	memcpy(eui + 4, &addr, 4);
1855 	return 0;
1856 }
1857 
1858 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
1859 {
1860 	if (dev->priv_flags & IFF_ISATAP)
1861 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1862 	return -1;
1863 }
1864 
1865 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
1866 {
1867 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1868 }
1869 
1870 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
1871 {
1872 	memcpy(eui, dev->perm_addr, 3);
1873 	memcpy(eui + 5, dev->perm_addr + 3, 3);
1874 	eui[3] = 0xFF;
1875 	eui[4] = 0xFE;
1876 	eui[0] ^= 2;
1877 	return 0;
1878 }
1879 
1880 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
1881 {
1882 	switch (dev->type) {
1883 	case ARPHRD_ETHER:
1884 	case ARPHRD_FDDI:
1885 		return addrconf_ifid_eui48(eui, dev);
1886 	case ARPHRD_ARCNET:
1887 		return addrconf_ifid_arcnet(eui, dev);
1888 	case ARPHRD_INFINIBAND:
1889 		return addrconf_ifid_infiniband(eui, dev);
1890 	case ARPHRD_SIT:
1891 		return addrconf_ifid_sit(eui, dev);
1892 	case ARPHRD_IPGRE:
1893 		return addrconf_ifid_gre(eui, dev);
1894 	case ARPHRD_6LOWPAN:
1895 	case ARPHRD_IEEE802154:
1896 		return addrconf_ifid_eui64(eui, dev);
1897 	case ARPHRD_IEEE1394:
1898 		return addrconf_ifid_ieee1394(eui, dev);
1899 	case ARPHRD_TUNNEL6:
1900 		return addrconf_ifid_ip6tnl(eui, dev);
1901 	}
1902 	return -1;
1903 }
1904 
1905 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
1906 {
1907 	int err = -1;
1908 	struct inet6_ifaddr *ifp;
1909 
1910 	read_lock_bh(&idev->lock);
1911 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1912 		if (ifp->scope > IFA_LINK)
1913 			break;
1914 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
1915 			memcpy(eui, ifp->addr.s6_addr+8, 8);
1916 			err = 0;
1917 			break;
1918 		}
1919 	}
1920 	read_unlock_bh(&idev->lock);
1921 	return err;
1922 }
1923 
1924 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
1925 static void __ipv6_regen_rndid(struct inet6_dev *idev)
1926 {
1927 regen:
1928 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
1929 	idev->rndid[0] &= ~0x02;
1930 
1931 	/*
1932 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
1933 	 * check if generated address is not inappropriate
1934 	 *
1935 	 *  - Reserved subnet anycast (RFC 2526)
1936 	 *	11111101 11....11 1xxxxxxx
1937 	 *  - ISATAP (RFC4214) 6.1
1938 	 *	00-00-5E-FE-xx-xx-xx-xx
1939 	 *  - value 0
1940 	 *  - XXX: already assigned to an address on the device
1941 	 */
1942 	if (idev->rndid[0] == 0xfd &&
1943 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
1944 	    (idev->rndid[7]&0x80))
1945 		goto regen;
1946 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
1947 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
1948 			goto regen;
1949 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
1950 			goto regen;
1951 	}
1952 }
1953 
1954 static void ipv6_regen_rndid(unsigned long data)
1955 {
1956 	struct inet6_dev *idev = (struct inet6_dev *) data;
1957 	unsigned long expires;
1958 
1959 	rcu_read_lock_bh();
1960 	write_lock_bh(&idev->lock);
1961 
1962 	if (idev->dead)
1963 		goto out;
1964 
1965 	__ipv6_regen_rndid(idev);
1966 
1967 	expires = jiffies +
1968 		idev->cnf.temp_prefered_lft * HZ -
1969 		idev->cnf.regen_max_retry * idev->cnf.dad_transmits *
1970 		NEIGH_VAR(idev->nd_parms, RETRANS_TIME) -
1971 		idev->cnf.max_desync_factor * HZ;
1972 	if (time_before(expires, jiffies)) {
1973 		pr_warn("%s: too short regeneration interval; timer disabled for %s\n",
1974 			__func__, idev->dev->name);
1975 		goto out;
1976 	}
1977 
1978 	if (!mod_timer(&idev->regen_timer, expires))
1979 		in6_dev_hold(idev);
1980 
1981 out:
1982 	write_unlock_bh(&idev->lock);
1983 	rcu_read_unlock_bh();
1984 	in6_dev_put(idev);
1985 }
1986 
1987 static void  __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
1988 {
1989 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
1990 		__ipv6_regen_rndid(idev);
1991 }
1992 
1993 /*
1994  *	Add prefix route.
1995  */
1996 
1997 static void
1998 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
1999 		      unsigned long expires, u32 flags)
2000 {
2001 	struct fib6_config cfg = {
2002 		.fc_table = RT6_TABLE_PREFIX,
2003 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2004 		.fc_ifindex = dev->ifindex,
2005 		.fc_expires = expires,
2006 		.fc_dst_len = plen,
2007 		.fc_flags = RTF_UP | flags,
2008 		.fc_nlinfo.nl_net = dev_net(dev),
2009 		.fc_protocol = RTPROT_KERNEL,
2010 	};
2011 
2012 	cfg.fc_dst = *pfx;
2013 
2014 	/* Prevent useless cloning on PtP SIT.
2015 	   This thing is done here expecting that the whole
2016 	   class of non-broadcast devices need not cloning.
2017 	 */
2018 #if IS_ENABLED(CONFIG_IPV6_SIT)
2019 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2020 		cfg.fc_flags |= RTF_NONEXTHOP;
2021 #endif
2022 
2023 	ip6_route_add(&cfg);
2024 }
2025 
2026 
2027 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2028 						  int plen,
2029 						  const struct net_device *dev,
2030 						  u32 flags, u32 noflags)
2031 {
2032 	struct fib6_node *fn;
2033 	struct rt6_info *rt = NULL;
2034 	struct fib6_table *table;
2035 
2036 	table = fib6_get_table(dev_net(dev), RT6_TABLE_PREFIX);
2037 	if (table == NULL)
2038 		return NULL;
2039 
2040 	read_lock_bh(&table->tb6_lock);
2041 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
2042 	if (!fn)
2043 		goto out;
2044 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2045 		if (rt->dst.dev->ifindex != dev->ifindex)
2046 			continue;
2047 		if ((rt->rt6i_flags & flags) != flags)
2048 			continue;
2049 		if ((rt->rt6i_flags & noflags) != 0)
2050 			continue;
2051 		dst_hold(&rt->dst);
2052 		break;
2053 	}
2054 out:
2055 	read_unlock_bh(&table->tb6_lock);
2056 	return rt;
2057 }
2058 
2059 
2060 /* Create "default" multicast route to the interface */
2061 
2062 static void addrconf_add_mroute(struct net_device *dev)
2063 {
2064 	struct fib6_config cfg = {
2065 		.fc_table = RT6_TABLE_LOCAL,
2066 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2067 		.fc_ifindex = dev->ifindex,
2068 		.fc_dst_len = 8,
2069 		.fc_flags = RTF_UP,
2070 		.fc_nlinfo.nl_net = dev_net(dev),
2071 	};
2072 
2073 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2074 
2075 	ip6_route_add(&cfg);
2076 }
2077 
2078 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2079 {
2080 	struct inet6_dev *idev;
2081 
2082 	ASSERT_RTNL();
2083 
2084 	idev = ipv6_find_idev(dev);
2085 	if (!idev)
2086 		return ERR_PTR(-ENOBUFS);
2087 
2088 	if (idev->cnf.disable_ipv6)
2089 		return ERR_PTR(-EACCES);
2090 
2091 	/* Add default multicast route */
2092 	if (!(dev->flags & IFF_LOOPBACK))
2093 		addrconf_add_mroute(dev);
2094 
2095 	return idev;
2096 }
2097 
2098 static void manage_tempaddrs(struct inet6_dev *idev,
2099 			     struct inet6_ifaddr *ifp,
2100 			     __u32 valid_lft, __u32 prefered_lft,
2101 			     bool create, unsigned long now)
2102 {
2103 	u32 flags;
2104 	struct inet6_ifaddr *ift;
2105 
2106 	read_lock_bh(&idev->lock);
2107 	/* update all temporary addresses in the list */
2108 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2109 		int age, max_valid, max_prefered;
2110 
2111 		if (ifp != ift->ifpub)
2112 			continue;
2113 
2114 		/* RFC 4941 section 3.3:
2115 		 * If a received option will extend the lifetime of a public
2116 		 * address, the lifetimes of temporary addresses should
2117 		 * be extended, subject to the overall constraint that no
2118 		 * temporary addresses should ever remain "valid" or "preferred"
2119 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2120 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2121 		 */
2122 		age = (now - ift->cstamp) / HZ;
2123 		max_valid = idev->cnf.temp_valid_lft - age;
2124 		if (max_valid < 0)
2125 			max_valid = 0;
2126 
2127 		max_prefered = idev->cnf.temp_prefered_lft -
2128 			       idev->cnf.max_desync_factor - age;
2129 		if (max_prefered < 0)
2130 			max_prefered = 0;
2131 
2132 		if (valid_lft > max_valid)
2133 			valid_lft = max_valid;
2134 
2135 		if (prefered_lft > max_prefered)
2136 			prefered_lft = max_prefered;
2137 
2138 		spin_lock(&ift->lock);
2139 		flags = ift->flags;
2140 		ift->valid_lft = valid_lft;
2141 		ift->prefered_lft = prefered_lft;
2142 		ift->tstamp = now;
2143 		if (prefered_lft > 0)
2144 			ift->flags &= ~IFA_F_DEPRECATED;
2145 
2146 		spin_unlock(&ift->lock);
2147 		if (!(flags&IFA_F_TENTATIVE))
2148 			ipv6_ifa_notify(0, ift);
2149 	}
2150 
2151 	if ((create || list_empty(&idev->tempaddr_list)) &&
2152 	    idev->cnf.use_tempaddr > 0) {
2153 		/* When a new public address is created as described
2154 		 * in [ADDRCONF], also create a new temporary address.
2155 		 * Also create a temporary address if it's enabled but
2156 		 * no temporary address currently exists.
2157 		 */
2158 		read_unlock_bh(&idev->lock);
2159 		ipv6_create_tempaddr(ifp, NULL);
2160 	} else {
2161 		read_unlock_bh(&idev->lock);
2162 	}
2163 }
2164 
2165 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2166 {
2167 	struct prefix_info *pinfo;
2168 	__u32 valid_lft;
2169 	__u32 prefered_lft;
2170 	int addr_type;
2171 	struct inet6_dev *in6_dev;
2172 	struct net *net = dev_net(dev);
2173 
2174 	pinfo = (struct prefix_info *) opt;
2175 
2176 	if (len < sizeof(struct prefix_info)) {
2177 		ADBG("addrconf: prefix option too short\n");
2178 		return;
2179 	}
2180 
2181 	/*
2182 	 *	Validation checks ([ADDRCONF], page 19)
2183 	 */
2184 
2185 	addr_type = ipv6_addr_type(&pinfo->prefix);
2186 
2187 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2188 		return;
2189 
2190 	valid_lft = ntohl(pinfo->valid);
2191 	prefered_lft = ntohl(pinfo->prefered);
2192 
2193 	if (prefered_lft > valid_lft) {
2194 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2195 		return;
2196 	}
2197 
2198 	in6_dev = in6_dev_get(dev);
2199 
2200 	if (in6_dev == NULL) {
2201 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2202 				    dev->name);
2203 		return;
2204 	}
2205 
2206 	/*
2207 	 *	Two things going on here:
2208 	 *	1) Add routes for on-link prefixes
2209 	 *	2) Configure prefixes with the auto flag set
2210 	 */
2211 
2212 	if (pinfo->onlink) {
2213 		struct rt6_info *rt;
2214 		unsigned long rt_expires;
2215 
2216 		/* Avoid arithmetic overflow. Really, we could
2217 		 * save rt_expires in seconds, likely valid_lft,
2218 		 * but it would require division in fib gc, that it
2219 		 * not good.
2220 		 */
2221 		if (HZ > USER_HZ)
2222 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2223 		else
2224 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2225 
2226 		if (addrconf_finite_timeout(rt_expires))
2227 			rt_expires *= HZ;
2228 
2229 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2230 					       pinfo->prefix_len,
2231 					       dev,
2232 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2233 					       RTF_GATEWAY | RTF_DEFAULT);
2234 
2235 		if (rt) {
2236 			/* Autoconf prefix route */
2237 			if (valid_lft == 0) {
2238 				ip6_del_rt(rt);
2239 				rt = NULL;
2240 			} else if (addrconf_finite_timeout(rt_expires)) {
2241 				/* not infinity */
2242 				rt6_set_expires(rt, jiffies + rt_expires);
2243 			} else {
2244 				rt6_clean_expires(rt);
2245 			}
2246 		} else if (valid_lft) {
2247 			clock_t expires = 0;
2248 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2249 			if (addrconf_finite_timeout(rt_expires)) {
2250 				/* not infinity */
2251 				flags |= RTF_EXPIRES;
2252 				expires = jiffies_to_clock_t(rt_expires);
2253 			}
2254 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2255 					      dev, expires, flags);
2256 		}
2257 		ip6_rt_put(rt);
2258 	}
2259 
2260 	/* Try to figure out our local address for this prefix */
2261 
2262 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2263 		struct inet6_ifaddr *ifp;
2264 		struct in6_addr addr;
2265 		int create = 0, update_lft = 0;
2266 		bool tokenized = false;
2267 
2268 		if (pinfo->prefix_len == 64) {
2269 			memcpy(&addr, &pinfo->prefix, 8);
2270 
2271 			if (!ipv6_addr_any(&in6_dev->token)) {
2272 				read_lock_bh(&in6_dev->lock);
2273 				memcpy(addr.s6_addr + 8,
2274 				       in6_dev->token.s6_addr + 8, 8);
2275 				read_unlock_bh(&in6_dev->lock);
2276 				tokenized = true;
2277 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2278 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2279 				in6_dev_put(in6_dev);
2280 				return;
2281 			}
2282 			goto ok;
2283 		}
2284 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2285 				    pinfo->prefix_len);
2286 		in6_dev_put(in6_dev);
2287 		return;
2288 
2289 ok:
2290 
2291 		ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
2292 
2293 		if (ifp == NULL && valid_lft) {
2294 			int max_addresses = in6_dev->cnf.max_addresses;
2295 			u32 addr_flags = 0;
2296 
2297 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2298 			if (in6_dev->cnf.optimistic_dad &&
2299 			    !net->ipv6.devconf_all->forwarding && sllao)
2300 				addr_flags = IFA_F_OPTIMISTIC;
2301 #endif
2302 
2303 			/* Do not allow to create too much of autoconfigured
2304 			 * addresses; this would be too easy way to crash kernel.
2305 			 */
2306 			if (!max_addresses ||
2307 			    ipv6_count_addresses(in6_dev) < max_addresses)
2308 				ifp = ipv6_add_addr(in6_dev, &addr, NULL,
2309 						    pinfo->prefix_len,
2310 						    addr_type&IPV6_ADDR_SCOPE_MASK,
2311 						    addr_flags, valid_lft,
2312 						    prefered_lft);
2313 
2314 			if (IS_ERR_OR_NULL(ifp)) {
2315 				in6_dev_put(in6_dev);
2316 				return;
2317 			}
2318 
2319 			update_lft = 0;
2320 			create = 1;
2321 			spin_lock_bh(&ifp->lock);
2322 			ifp->flags |= IFA_F_MANAGETEMPADDR;
2323 			ifp->cstamp = jiffies;
2324 			ifp->tokenized = tokenized;
2325 			spin_unlock_bh(&ifp->lock);
2326 			addrconf_dad_start(ifp);
2327 		}
2328 
2329 		if (ifp) {
2330 			u32 flags;
2331 			unsigned long now;
2332 			u32 stored_lft;
2333 
2334 			/* update lifetime (RFC2462 5.5.3 e) */
2335 			spin_lock(&ifp->lock);
2336 			now = jiffies;
2337 			if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2338 				stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2339 			else
2340 				stored_lft = 0;
2341 			if (!update_lft && !create && stored_lft) {
2342 				const u32 minimum_lft = min_t(u32,
2343 					stored_lft, MIN_VALID_LIFETIME);
2344 				valid_lft = max(valid_lft, minimum_lft);
2345 
2346 				/* RFC4862 Section 5.5.3e:
2347 				 * "Note that the preferred lifetime of the
2348 				 *  corresponding address is always reset to
2349 				 *  the Preferred Lifetime in the received
2350 				 *  Prefix Information option, regardless of
2351 				 *  whether the valid lifetime is also reset or
2352 				 *  ignored."
2353 				 *
2354 				 * So we should always update prefered_lft here.
2355 				 */
2356 				update_lft = 1;
2357 			}
2358 
2359 			if (update_lft) {
2360 				ifp->valid_lft = valid_lft;
2361 				ifp->prefered_lft = prefered_lft;
2362 				ifp->tstamp = now;
2363 				flags = ifp->flags;
2364 				ifp->flags &= ~IFA_F_DEPRECATED;
2365 				spin_unlock(&ifp->lock);
2366 
2367 				if (!(flags&IFA_F_TENTATIVE))
2368 					ipv6_ifa_notify(0, ifp);
2369 			} else
2370 				spin_unlock(&ifp->lock);
2371 
2372 			manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2373 					 create, now);
2374 
2375 			in6_ifa_put(ifp);
2376 			addrconf_verify();
2377 		}
2378 	}
2379 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2380 	in6_dev_put(in6_dev);
2381 }
2382 
2383 /*
2384  *	Set destination address.
2385  *	Special case for SIT interfaces where we create a new "virtual"
2386  *	device.
2387  */
2388 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2389 {
2390 	struct in6_ifreq ireq;
2391 	struct net_device *dev;
2392 	int err = -EINVAL;
2393 
2394 	rtnl_lock();
2395 
2396 	err = -EFAULT;
2397 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2398 		goto err_exit;
2399 
2400 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2401 
2402 	err = -ENODEV;
2403 	if (dev == NULL)
2404 		goto err_exit;
2405 
2406 #if IS_ENABLED(CONFIG_IPV6_SIT)
2407 	if (dev->type == ARPHRD_SIT) {
2408 		const struct net_device_ops *ops = dev->netdev_ops;
2409 		struct ifreq ifr;
2410 		struct ip_tunnel_parm p;
2411 
2412 		err = -EADDRNOTAVAIL;
2413 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2414 			goto err_exit;
2415 
2416 		memset(&p, 0, sizeof(p));
2417 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2418 		p.iph.saddr = 0;
2419 		p.iph.version = 4;
2420 		p.iph.ihl = 5;
2421 		p.iph.protocol = IPPROTO_IPV6;
2422 		p.iph.ttl = 64;
2423 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2424 
2425 		if (ops->ndo_do_ioctl) {
2426 			mm_segment_t oldfs = get_fs();
2427 
2428 			set_fs(KERNEL_DS);
2429 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2430 			set_fs(oldfs);
2431 		} else
2432 			err = -EOPNOTSUPP;
2433 
2434 		if (err == 0) {
2435 			err = -ENOBUFS;
2436 			dev = __dev_get_by_name(net, p.name);
2437 			if (!dev)
2438 				goto err_exit;
2439 			err = dev_open(dev);
2440 		}
2441 	}
2442 #endif
2443 
2444 err_exit:
2445 	rtnl_unlock();
2446 	return err;
2447 }
2448 
2449 /*
2450  *	Manual configuration of address on an interface
2451  */
2452 static int inet6_addr_add(struct net *net, int ifindex,
2453 			  const struct in6_addr *pfx,
2454 			  const struct in6_addr *peer_pfx,
2455 			  unsigned int plen, __u32 ifa_flags,
2456 			  __u32 prefered_lft, __u32 valid_lft)
2457 {
2458 	struct inet6_ifaddr *ifp;
2459 	struct inet6_dev *idev;
2460 	struct net_device *dev;
2461 	int scope;
2462 	u32 flags;
2463 	clock_t expires;
2464 	unsigned long timeout;
2465 
2466 	ASSERT_RTNL();
2467 
2468 	if (plen > 128)
2469 		return -EINVAL;
2470 
2471 	/* check the lifetime */
2472 	if (!valid_lft || prefered_lft > valid_lft)
2473 		return -EINVAL;
2474 
2475 	if (ifa_flags & IFA_F_MANAGETEMPADDR && plen != 64)
2476 		return -EINVAL;
2477 
2478 	dev = __dev_get_by_index(net, ifindex);
2479 	if (!dev)
2480 		return -ENODEV;
2481 
2482 	idev = addrconf_add_dev(dev);
2483 	if (IS_ERR(idev))
2484 		return PTR_ERR(idev);
2485 
2486 	scope = ipv6_addr_scope(pfx);
2487 
2488 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2489 	if (addrconf_finite_timeout(timeout)) {
2490 		expires = jiffies_to_clock_t(timeout * HZ);
2491 		valid_lft = timeout;
2492 		flags = RTF_EXPIRES;
2493 	} else {
2494 		expires = 0;
2495 		flags = 0;
2496 		ifa_flags |= IFA_F_PERMANENT;
2497 	}
2498 
2499 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2500 	if (addrconf_finite_timeout(timeout)) {
2501 		if (timeout == 0)
2502 			ifa_flags |= IFA_F_DEPRECATED;
2503 		prefered_lft = timeout;
2504 	}
2505 
2506 	ifp = ipv6_add_addr(idev, pfx, peer_pfx, plen, scope, ifa_flags,
2507 			    valid_lft, prefered_lft);
2508 
2509 	if (!IS_ERR(ifp)) {
2510 		if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
2511 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2512 					      expires, flags);
2513 		}
2514 
2515 		/*
2516 		 * Note that section 3.1 of RFC 4429 indicates
2517 		 * that the Optimistic flag should not be set for
2518 		 * manually configured addresses
2519 		 */
2520 		addrconf_dad_start(ifp);
2521 		if (ifa_flags & IFA_F_MANAGETEMPADDR)
2522 			manage_tempaddrs(idev, ifp, valid_lft, prefered_lft,
2523 					 true, jiffies);
2524 		in6_ifa_put(ifp);
2525 		addrconf_verify_rtnl();
2526 		return 0;
2527 	}
2528 
2529 	return PTR_ERR(ifp);
2530 }
2531 
2532 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2533 			  const struct in6_addr *pfx, unsigned int plen)
2534 {
2535 	struct inet6_ifaddr *ifp;
2536 	struct inet6_dev *idev;
2537 	struct net_device *dev;
2538 
2539 	if (plen > 128)
2540 		return -EINVAL;
2541 
2542 	dev = __dev_get_by_index(net, ifindex);
2543 	if (!dev)
2544 		return -ENODEV;
2545 
2546 	idev = __in6_dev_get(dev);
2547 	if (idev == NULL)
2548 		return -ENXIO;
2549 
2550 	read_lock_bh(&idev->lock);
2551 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2552 		if (ifp->prefix_len == plen &&
2553 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2554 			in6_ifa_hold(ifp);
2555 			read_unlock_bh(&idev->lock);
2556 
2557 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
2558 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
2559 				manage_tempaddrs(idev, ifp, 0, 0, false,
2560 						 jiffies);
2561 			ipv6_del_addr(ifp);
2562 			addrconf_verify_rtnl();
2563 			return 0;
2564 		}
2565 	}
2566 	read_unlock_bh(&idev->lock);
2567 	return -EADDRNOTAVAIL;
2568 }
2569 
2570 
2571 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2572 {
2573 	struct in6_ifreq ireq;
2574 	int err;
2575 
2576 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2577 		return -EPERM;
2578 
2579 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2580 		return -EFAULT;
2581 
2582 	rtnl_lock();
2583 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr, NULL,
2584 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2585 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2586 	rtnl_unlock();
2587 	return err;
2588 }
2589 
2590 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2591 {
2592 	struct in6_ifreq ireq;
2593 	int err;
2594 
2595 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2596 		return -EPERM;
2597 
2598 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2599 		return -EFAULT;
2600 
2601 	rtnl_lock();
2602 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
2603 			     ireq.ifr6_prefixlen);
2604 	rtnl_unlock();
2605 	return err;
2606 }
2607 
2608 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2609 		     int plen, int scope)
2610 {
2611 	struct inet6_ifaddr *ifp;
2612 
2613 	ifp = ipv6_add_addr(idev, addr, NULL, plen,
2614 			    scope, IFA_F_PERMANENT,
2615 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2616 	if (!IS_ERR(ifp)) {
2617 		spin_lock_bh(&ifp->lock);
2618 		ifp->flags &= ~IFA_F_TENTATIVE;
2619 		spin_unlock_bh(&ifp->lock);
2620 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2621 		in6_ifa_put(ifp);
2622 	}
2623 }
2624 
2625 #if IS_ENABLED(CONFIG_IPV6_SIT)
2626 static void sit_add_v4_addrs(struct inet6_dev *idev)
2627 {
2628 	struct in6_addr addr;
2629 	struct net_device *dev;
2630 	struct net *net = dev_net(idev->dev);
2631 	int scope, plen;
2632 	u32 pflags = 0;
2633 
2634 	ASSERT_RTNL();
2635 
2636 	memset(&addr, 0, sizeof(struct in6_addr));
2637 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2638 
2639 	if (idev->dev->flags&IFF_POINTOPOINT) {
2640 		addr.s6_addr32[0] = htonl(0xfe800000);
2641 		scope = IFA_LINK;
2642 		plen = 64;
2643 	} else {
2644 		scope = IPV6_ADDR_COMPATv4;
2645 		plen = 96;
2646 		pflags |= RTF_NONEXTHOP;
2647 	}
2648 
2649 	if (addr.s6_addr32[3]) {
2650 		add_addr(idev, &addr, plen, scope);
2651 		addrconf_prefix_route(&addr, plen, idev->dev, 0, pflags);
2652 		return;
2653 	}
2654 
2655 	for_each_netdev(net, dev) {
2656 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
2657 		if (in_dev && (dev->flags & IFF_UP)) {
2658 			struct in_ifaddr *ifa;
2659 
2660 			int flag = scope;
2661 
2662 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2663 
2664 				addr.s6_addr32[3] = ifa->ifa_local;
2665 
2666 				if (ifa->ifa_scope == RT_SCOPE_LINK)
2667 					continue;
2668 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2669 					if (idev->dev->flags&IFF_POINTOPOINT)
2670 						continue;
2671 					flag |= IFA_HOST;
2672 				}
2673 
2674 				add_addr(idev, &addr, plen, flag);
2675 				addrconf_prefix_route(&addr, plen, idev->dev, 0,
2676 						      pflags);
2677 			}
2678 		}
2679 	}
2680 }
2681 #endif
2682 
2683 static void init_loopback(struct net_device *dev)
2684 {
2685 	struct inet6_dev  *idev;
2686 	struct net_device *sp_dev;
2687 	struct inet6_ifaddr *sp_ifa;
2688 	struct rt6_info *sp_rt;
2689 
2690 	/* ::1 */
2691 
2692 	ASSERT_RTNL();
2693 
2694 	idev = ipv6_find_idev(dev);
2695 	if (idev == NULL) {
2696 		pr_debug("%s: add_dev failed\n", __func__);
2697 		return;
2698 	}
2699 
2700 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2701 
2702 	/* Add routes to other interface's IPv6 addresses */
2703 	for_each_netdev(dev_net(dev), sp_dev) {
2704 		if (!strcmp(sp_dev->name, dev->name))
2705 			continue;
2706 
2707 		idev = __in6_dev_get(sp_dev);
2708 		if (!idev)
2709 			continue;
2710 
2711 		read_lock_bh(&idev->lock);
2712 		list_for_each_entry(sp_ifa, &idev->addr_list, if_list) {
2713 
2714 			if (sp_ifa->flags & (IFA_F_DADFAILED | IFA_F_TENTATIVE))
2715 				continue;
2716 
2717 			if (sp_ifa->rt) {
2718 				/* This dst has been added to garbage list when
2719 				 * lo device down, release this obsolete dst and
2720 				 * reallocate a new router for ifa.
2721 				 */
2722 				if (sp_ifa->rt->dst.obsolete > 0) {
2723 					ip6_rt_put(sp_ifa->rt);
2724 					sp_ifa->rt = NULL;
2725 				} else {
2726 					continue;
2727 				}
2728 			}
2729 
2730 			sp_rt = addrconf_dst_alloc(idev, &sp_ifa->addr, false);
2731 
2732 			/* Failure cases are ignored */
2733 			if (!IS_ERR(sp_rt)) {
2734 				sp_ifa->rt = sp_rt;
2735 				ip6_ins_rt(sp_rt);
2736 			}
2737 		}
2738 		read_unlock_bh(&idev->lock);
2739 	}
2740 }
2741 
2742 static void addrconf_add_linklocal(struct inet6_dev *idev, const struct in6_addr *addr)
2743 {
2744 	struct inet6_ifaddr *ifp;
2745 	u32 addr_flags = IFA_F_PERMANENT;
2746 
2747 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2748 	if (idev->cnf.optimistic_dad &&
2749 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
2750 		addr_flags |= IFA_F_OPTIMISTIC;
2751 #endif
2752 
2753 
2754 	ifp = ipv6_add_addr(idev, addr, NULL, 64, IFA_LINK, addr_flags,
2755 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2756 	if (!IS_ERR(ifp)) {
2757 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
2758 		addrconf_dad_start(ifp);
2759 		in6_ifa_put(ifp);
2760 	}
2761 }
2762 
2763 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
2764 {
2765 	if (idev->addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64) {
2766 		struct in6_addr addr;
2767 
2768 		ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2769 		/* addrconf_add_linklocal also adds a prefix_route and we
2770 		 * only need to care about prefix routes if ipv6_generate_eui64
2771 		 * couldn't generate one.
2772 		 */
2773 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
2774 			addrconf_add_linklocal(idev, &addr);
2775 		else if (prefix_route)
2776 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
2777 	}
2778 }
2779 
2780 static void addrconf_dev_config(struct net_device *dev)
2781 {
2782 	struct inet6_dev *idev;
2783 
2784 	ASSERT_RTNL();
2785 
2786 	if ((dev->type != ARPHRD_ETHER) &&
2787 	    (dev->type != ARPHRD_FDDI) &&
2788 	    (dev->type != ARPHRD_ARCNET) &&
2789 	    (dev->type != ARPHRD_INFINIBAND) &&
2790 	    (dev->type != ARPHRD_IEEE802154) &&
2791 	    (dev->type != ARPHRD_IEEE1394) &&
2792 	    (dev->type != ARPHRD_TUNNEL6) &&
2793 	    (dev->type != ARPHRD_6LOWPAN)) {
2794 		/* Alas, we support only Ethernet autoconfiguration. */
2795 		return;
2796 	}
2797 
2798 	idev = addrconf_add_dev(dev);
2799 	if (IS_ERR(idev))
2800 		return;
2801 
2802 	addrconf_addr_gen(idev, false);
2803 }
2804 
2805 #if IS_ENABLED(CONFIG_IPV6_SIT)
2806 static void addrconf_sit_config(struct net_device *dev)
2807 {
2808 	struct inet6_dev *idev;
2809 
2810 	ASSERT_RTNL();
2811 
2812 	/*
2813 	 * Configure the tunnel with one of our IPv4
2814 	 * addresses... we should configure all of
2815 	 * our v4 addrs in the tunnel
2816 	 */
2817 
2818 	idev = ipv6_find_idev(dev);
2819 	if (idev == NULL) {
2820 		pr_debug("%s: add_dev failed\n", __func__);
2821 		return;
2822 	}
2823 
2824 	if (dev->priv_flags & IFF_ISATAP) {
2825 		addrconf_addr_gen(idev, false);
2826 		return;
2827 	}
2828 
2829 	sit_add_v4_addrs(idev);
2830 
2831 	if (dev->flags&IFF_POINTOPOINT)
2832 		addrconf_add_mroute(dev);
2833 }
2834 #endif
2835 
2836 #if IS_ENABLED(CONFIG_NET_IPGRE)
2837 static void addrconf_gre_config(struct net_device *dev)
2838 {
2839 	struct inet6_dev *idev;
2840 
2841 	ASSERT_RTNL();
2842 
2843 	idev = ipv6_find_idev(dev);
2844 	if (idev == NULL) {
2845 		pr_debug("%s: add_dev failed\n", __func__);
2846 		return;
2847 	}
2848 
2849 	addrconf_addr_gen(idev, true);
2850 }
2851 #endif
2852 
2853 static int addrconf_notify(struct notifier_block *this, unsigned long event,
2854 			   void *ptr)
2855 {
2856 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2857 	struct inet6_dev *idev = __in6_dev_get(dev);
2858 	int run_pending = 0;
2859 	int err;
2860 
2861 	switch (event) {
2862 	case NETDEV_REGISTER:
2863 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2864 			idev = ipv6_add_dev(dev);
2865 			if (IS_ERR(idev))
2866 				return notifier_from_errno(PTR_ERR(idev));
2867 		}
2868 		break;
2869 
2870 	case NETDEV_UP:
2871 	case NETDEV_CHANGE:
2872 		if (dev->flags & IFF_SLAVE)
2873 			break;
2874 
2875 		if (idev && idev->cnf.disable_ipv6)
2876 			break;
2877 
2878 		if (event == NETDEV_UP) {
2879 			if (!addrconf_qdisc_ok(dev)) {
2880 				/* device is not ready yet. */
2881 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
2882 					dev->name);
2883 				break;
2884 			}
2885 
2886 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
2887 				idev = ipv6_add_dev(dev);
2888 
2889 			if (!IS_ERR_OR_NULL(idev)) {
2890 				idev->if_flags |= IF_READY;
2891 				run_pending = 1;
2892 			}
2893 		} else {
2894 			if (!addrconf_qdisc_ok(dev)) {
2895 				/* device is still not ready. */
2896 				break;
2897 			}
2898 
2899 			if (idev) {
2900 				if (idev->if_flags & IF_READY)
2901 					/* device is already configured. */
2902 					break;
2903 				idev->if_flags |= IF_READY;
2904 			}
2905 
2906 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
2907 				dev->name);
2908 
2909 			run_pending = 1;
2910 		}
2911 
2912 		switch (dev->type) {
2913 #if IS_ENABLED(CONFIG_IPV6_SIT)
2914 		case ARPHRD_SIT:
2915 			addrconf_sit_config(dev);
2916 			break;
2917 #endif
2918 #if IS_ENABLED(CONFIG_NET_IPGRE)
2919 		case ARPHRD_IPGRE:
2920 			addrconf_gre_config(dev);
2921 			break;
2922 #endif
2923 		case ARPHRD_LOOPBACK:
2924 			init_loopback(dev);
2925 			break;
2926 
2927 		default:
2928 			addrconf_dev_config(dev);
2929 			break;
2930 		}
2931 
2932 		if (!IS_ERR_OR_NULL(idev)) {
2933 			if (run_pending)
2934 				addrconf_dad_run(idev);
2935 
2936 			/*
2937 			 * If the MTU changed during the interface down,
2938 			 * when the interface up, the changed MTU must be
2939 			 * reflected in the idev as well as routers.
2940 			 */
2941 			if (idev->cnf.mtu6 != dev->mtu &&
2942 			    dev->mtu >= IPV6_MIN_MTU) {
2943 				rt6_mtu_change(dev, dev->mtu);
2944 				idev->cnf.mtu6 = dev->mtu;
2945 			}
2946 			idev->tstamp = jiffies;
2947 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
2948 
2949 			/*
2950 			 * If the changed mtu during down is lower than
2951 			 * IPV6_MIN_MTU stop IPv6 on this interface.
2952 			 */
2953 			if (dev->mtu < IPV6_MIN_MTU)
2954 				addrconf_ifdown(dev, 1);
2955 		}
2956 		break;
2957 
2958 	case NETDEV_CHANGEMTU:
2959 		if (idev && dev->mtu >= IPV6_MIN_MTU) {
2960 			rt6_mtu_change(dev, dev->mtu);
2961 			idev->cnf.mtu6 = dev->mtu;
2962 			break;
2963 		}
2964 
2965 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2966 			idev = ipv6_add_dev(dev);
2967 			if (!IS_ERR(idev))
2968 				break;
2969 		}
2970 
2971 		/*
2972 		 * if MTU under IPV6_MIN_MTU.
2973 		 * Stop IPv6 on this interface.
2974 		 */
2975 
2976 	case NETDEV_DOWN:
2977 	case NETDEV_UNREGISTER:
2978 		/*
2979 		 *	Remove all addresses from this interface.
2980 		 */
2981 		addrconf_ifdown(dev, event != NETDEV_DOWN);
2982 		break;
2983 
2984 	case NETDEV_CHANGENAME:
2985 		if (idev) {
2986 			snmp6_unregister_dev(idev);
2987 			addrconf_sysctl_unregister(idev);
2988 			err = addrconf_sysctl_register(idev);
2989 			if (err)
2990 				return notifier_from_errno(err);
2991 			err = snmp6_register_dev(idev);
2992 			if (err) {
2993 				addrconf_sysctl_unregister(idev);
2994 				return notifier_from_errno(err);
2995 			}
2996 		}
2997 		break;
2998 
2999 	case NETDEV_PRE_TYPE_CHANGE:
3000 	case NETDEV_POST_TYPE_CHANGE:
3001 		addrconf_type_change(dev, event);
3002 		break;
3003 	}
3004 
3005 	return NOTIFY_OK;
3006 }
3007 
3008 /*
3009  *	addrconf module should be notified of a device going up
3010  */
3011 static struct notifier_block ipv6_dev_notf = {
3012 	.notifier_call = addrconf_notify,
3013 };
3014 
3015 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3016 {
3017 	struct inet6_dev *idev;
3018 	ASSERT_RTNL();
3019 
3020 	idev = __in6_dev_get(dev);
3021 
3022 	if (event == NETDEV_POST_TYPE_CHANGE)
3023 		ipv6_mc_remap(idev);
3024 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3025 		ipv6_mc_unmap(idev);
3026 }
3027 
3028 static int addrconf_ifdown(struct net_device *dev, int how)
3029 {
3030 	struct net *net = dev_net(dev);
3031 	struct inet6_dev *idev;
3032 	struct inet6_ifaddr *ifa;
3033 	int state, i;
3034 
3035 	ASSERT_RTNL();
3036 
3037 	rt6_ifdown(net, dev);
3038 	neigh_ifdown(&nd_tbl, dev);
3039 
3040 	idev = __in6_dev_get(dev);
3041 	if (idev == NULL)
3042 		return -ENODEV;
3043 
3044 	/*
3045 	 * Step 1: remove reference to ipv6 device from parent device.
3046 	 *	   Do not dev_put!
3047 	 */
3048 	if (how) {
3049 		idev->dead = 1;
3050 
3051 		/* protected by rtnl_lock */
3052 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3053 
3054 		/* Step 1.5: remove snmp6 entry */
3055 		snmp6_unregister_dev(idev);
3056 
3057 	}
3058 
3059 	/* Step 2: clear hash table */
3060 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3061 		struct hlist_head *h = &inet6_addr_lst[i];
3062 
3063 		spin_lock_bh(&addrconf_hash_lock);
3064 restart:
3065 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3066 			if (ifa->idev == idev) {
3067 				hlist_del_init_rcu(&ifa->addr_lst);
3068 				addrconf_del_dad_work(ifa);
3069 				goto restart;
3070 			}
3071 		}
3072 		spin_unlock_bh(&addrconf_hash_lock);
3073 	}
3074 
3075 	write_lock_bh(&idev->lock);
3076 
3077 	addrconf_del_rs_timer(idev);
3078 
3079 	/* Step 2: clear flags for stateless addrconf */
3080 	if (!how)
3081 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3082 
3083 	if (how && del_timer(&idev->regen_timer))
3084 		in6_dev_put(idev);
3085 
3086 	/* Step 3: clear tempaddr list */
3087 	while (!list_empty(&idev->tempaddr_list)) {
3088 		ifa = list_first_entry(&idev->tempaddr_list,
3089 				       struct inet6_ifaddr, tmp_list);
3090 		list_del(&ifa->tmp_list);
3091 		write_unlock_bh(&idev->lock);
3092 		spin_lock_bh(&ifa->lock);
3093 
3094 		if (ifa->ifpub) {
3095 			in6_ifa_put(ifa->ifpub);
3096 			ifa->ifpub = NULL;
3097 		}
3098 		spin_unlock_bh(&ifa->lock);
3099 		in6_ifa_put(ifa);
3100 		write_lock_bh(&idev->lock);
3101 	}
3102 
3103 	while (!list_empty(&idev->addr_list)) {
3104 		ifa = list_first_entry(&idev->addr_list,
3105 				       struct inet6_ifaddr, if_list);
3106 		addrconf_del_dad_work(ifa);
3107 
3108 		list_del(&ifa->if_list);
3109 
3110 		write_unlock_bh(&idev->lock);
3111 
3112 		spin_lock_bh(&ifa->state_lock);
3113 		state = ifa->state;
3114 		ifa->state = INET6_IFADDR_STATE_DEAD;
3115 		spin_unlock_bh(&ifa->state_lock);
3116 
3117 		if (state != INET6_IFADDR_STATE_DEAD) {
3118 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3119 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3120 		}
3121 		in6_ifa_put(ifa);
3122 
3123 		write_lock_bh(&idev->lock);
3124 	}
3125 
3126 	write_unlock_bh(&idev->lock);
3127 
3128 	/* Step 5: Discard anycast and multicast list */
3129 	if (how) {
3130 		ipv6_ac_destroy_dev(idev);
3131 		ipv6_mc_destroy_dev(idev);
3132 	} else {
3133 		ipv6_mc_down(idev);
3134 	}
3135 
3136 	idev->tstamp = jiffies;
3137 
3138 	/* Last: Shot the device (if unregistered) */
3139 	if (how) {
3140 		addrconf_sysctl_unregister(idev);
3141 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3142 		neigh_ifdown(&nd_tbl, dev);
3143 		in6_dev_put(idev);
3144 	}
3145 	return 0;
3146 }
3147 
3148 static void addrconf_rs_timer(unsigned long data)
3149 {
3150 	struct inet6_dev *idev = (struct inet6_dev *)data;
3151 	struct net_device *dev = idev->dev;
3152 	struct in6_addr lladdr;
3153 
3154 	write_lock(&idev->lock);
3155 	if (idev->dead || !(idev->if_flags & IF_READY))
3156 		goto out;
3157 
3158 	if (!ipv6_accept_ra(idev))
3159 		goto out;
3160 
3161 	/* Announcement received after solicitation was sent */
3162 	if (idev->if_flags & IF_RA_RCVD)
3163 		goto out;
3164 
3165 	if (idev->rs_probes++ < idev->cnf.rtr_solicits) {
3166 		write_unlock(&idev->lock);
3167 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3168 			ndisc_send_rs(dev, &lladdr,
3169 				      &in6addr_linklocal_allrouters);
3170 		else
3171 			goto put;
3172 
3173 		write_lock(&idev->lock);
3174 		/* The wait after the last probe can be shorter */
3175 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3176 					     idev->cnf.rtr_solicits) ?
3177 				      idev->cnf.rtr_solicit_delay :
3178 				      idev->cnf.rtr_solicit_interval);
3179 	} else {
3180 		/*
3181 		 * Note: we do not support deprecated "all on-link"
3182 		 * assumption any longer.
3183 		 */
3184 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3185 	}
3186 
3187 out:
3188 	write_unlock(&idev->lock);
3189 put:
3190 	in6_dev_put(idev);
3191 }
3192 
3193 /*
3194  *	Duplicate Address Detection
3195  */
3196 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3197 {
3198 	unsigned long rand_num;
3199 	struct inet6_dev *idev = ifp->idev;
3200 
3201 	if (ifp->flags & IFA_F_OPTIMISTIC)
3202 		rand_num = 0;
3203 	else
3204 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3205 
3206 	ifp->dad_probes = idev->cnf.dad_transmits;
3207 	addrconf_mod_dad_work(ifp, rand_num);
3208 }
3209 
3210 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3211 {
3212 	struct inet6_dev *idev = ifp->idev;
3213 	struct net_device *dev = idev->dev;
3214 
3215 	addrconf_join_solict(dev, &ifp->addr);
3216 
3217 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3218 
3219 	read_lock_bh(&idev->lock);
3220 	spin_lock(&ifp->lock);
3221 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3222 		goto out;
3223 
3224 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3225 	    idev->cnf.accept_dad < 1 ||
3226 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3227 	    ifp->flags & IFA_F_NODAD) {
3228 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3229 		spin_unlock(&ifp->lock);
3230 		read_unlock_bh(&idev->lock);
3231 
3232 		addrconf_dad_completed(ifp);
3233 		return;
3234 	}
3235 
3236 	if (!(idev->if_flags & IF_READY)) {
3237 		spin_unlock(&ifp->lock);
3238 		read_unlock_bh(&idev->lock);
3239 		/*
3240 		 * If the device is not ready:
3241 		 * - keep it tentative if it is a permanent address.
3242 		 * - otherwise, kill it.
3243 		 */
3244 		in6_ifa_hold(ifp);
3245 		addrconf_dad_stop(ifp, 0);
3246 		return;
3247 	}
3248 
3249 	/*
3250 	 * Optimistic nodes can start receiving
3251 	 * Frames right away
3252 	 */
3253 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3254 		ip6_ins_rt(ifp->rt);
3255 		if (ipv6_use_optimistic_addr(idev)) {
3256 			/* Because optimistic nodes can use this address,
3257 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3258 			 */
3259 			ipv6_ifa_notify(RTM_NEWADDR, ifp);
3260 		}
3261 	}
3262 
3263 	addrconf_dad_kick(ifp);
3264 out:
3265 	spin_unlock(&ifp->lock);
3266 	read_unlock_bh(&idev->lock);
3267 }
3268 
3269 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3270 {
3271 	bool begin_dad = false;
3272 
3273 	spin_lock_bh(&ifp->state_lock);
3274 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3275 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3276 		begin_dad = true;
3277 	}
3278 	spin_unlock_bh(&ifp->state_lock);
3279 
3280 	if (begin_dad)
3281 		addrconf_mod_dad_work(ifp, 0);
3282 }
3283 
3284 static void addrconf_dad_work(struct work_struct *w)
3285 {
3286 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3287 						struct inet6_ifaddr,
3288 						dad_work);
3289 	struct inet6_dev *idev = ifp->idev;
3290 	struct in6_addr mcaddr;
3291 
3292 	enum {
3293 		DAD_PROCESS,
3294 		DAD_BEGIN,
3295 		DAD_ABORT,
3296 	} action = DAD_PROCESS;
3297 
3298 	rtnl_lock();
3299 
3300 	spin_lock_bh(&ifp->state_lock);
3301 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3302 		action = DAD_BEGIN;
3303 		ifp->state = INET6_IFADDR_STATE_DAD;
3304 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3305 		action = DAD_ABORT;
3306 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
3307 	}
3308 	spin_unlock_bh(&ifp->state_lock);
3309 
3310 	if (action == DAD_BEGIN) {
3311 		addrconf_dad_begin(ifp);
3312 		goto out;
3313 	} else if (action == DAD_ABORT) {
3314 		addrconf_dad_stop(ifp, 1);
3315 		goto out;
3316 	}
3317 
3318 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
3319 		goto out;
3320 
3321 	write_lock_bh(&idev->lock);
3322 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3323 		write_unlock_bh(&idev->lock);
3324 		goto out;
3325 	}
3326 
3327 	spin_lock(&ifp->lock);
3328 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3329 		spin_unlock(&ifp->lock);
3330 		write_unlock_bh(&idev->lock);
3331 		goto out;
3332 	}
3333 
3334 	if (ifp->dad_probes == 0) {
3335 		/*
3336 		 * DAD was successful
3337 		 */
3338 
3339 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3340 		spin_unlock(&ifp->lock);
3341 		write_unlock_bh(&idev->lock);
3342 
3343 		addrconf_dad_completed(ifp);
3344 
3345 		goto out;
3346 	}
3347 
3348 	ifp->dad_probes--;
3349 	addrconf_mod_dad_work(ifp,
3350 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
3351 	spin_unlock(&ifp->lock);
3352 	write_unlock_bh(&idev->lock);
3353 
3354 	/* send a neighbour solicitation for our addr */
3355 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3356 	ndisc_send_ns(ifp->idev->dev, NULL, &ifp->addr, &mcaddr, &in6addr_any);
3357 out:
3358 	in6_ifa_put(ifp);
3359 	rtnl_unlock();
3360 }
3361 
3362 /* ifp->idev must be at least read locked */
3363 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
3364 {
3365 	struct inet6_ifaddr *ifpiter;
3366 	struct inet6_dev *idev = ifp->idev;
3367 
3368 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
3369 		if (ifpiter->scope > IFA_LINK)
3370 			break;
3371 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
3372 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
3373 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
3374 		    IFA_F_PERMANENT)
3375 			return false;
3376 	}
3377 	return true;
3378 }
3379 
3380 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
3381 {
3382 	struct net_device *dev = ifp->idev->dev;
3383 	struct in6_addr lladdr;
3384 	bool send_rs, send_mld;
3385 
3386 	addrconf_del_dad_work(ifp);
3387 
3388 	/*
3389 	 *	Configure the address for reception. Now it is valid.
3390 	 */
3391 
3392 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
3393 
3394 	/* If added prefix is link local and we are prepared to process
3395 	   router advertisements, start sending router solicitations.
3396 	 */
3397 
3398 	read_lock_bh(&ifp->idev->lock);
3399 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
3400 	send_rs = send_mld &&
3401 		  ipv6_accept_ra(ifp->idev) &&
3402 		  ifp->idev->cnf.rtr_solicits > 0 &&
3403 		  (dev->flags&IFF_LOOPBACK) == 0;
3404 	read_unlock_bh(&ifp->idev->lock);
3405 
3406 	/* While dad is in progress mld report's source address is in6_addrany.
3407 	 * Resend with proper ll now.
3408 	 */
3409 	if (send_mld)
3410 		ipv6_mc_dad_complete(ifp->idev);
3411 
3412 	if (send_rs) {
3413 		/*
3414 		 *	If a host as already performed a random delay
3415 		 *	[...] as part of DAD [...] there is no need
3416 		 *	to delay again before sending the first RS
3417 		 */
3418 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3419 			return;
3420 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
3421 
3422 		write_lock_bh(&ifp->idev->lock);
3423 		spin_lock(&ifp->lock);
3424 		ifp->idev->rs_probes = 1;
3425 		ifp->idev->if_flags |= IF_RS_SENT;
3426 		addrconf_mod_rs_timer(ifp->idev,
3427 				      ifp->idev->cnf.rtr_solicit_interval);
3428 		spin_unlock(&ifp->lock);
3429 		write_unlock_bh(&ifp->idev->lock);
3430 	}
3431 }
3432 
3433 static void addrconf_dad_run(struct inet6_dev *idev)
3434 {
3435 	struct inet6_ifaddr *ifp;
3436 
3437 	read_lock_bh(&idev->lock);
3438 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3439 		spin_lock(&ifp->lock);
3440 		if (ifp->flags & IFA_F_TENTATIVE &&
3441 		    ifp->state == INET6_IFADDR_STATE_DAD)
3442 			addrconf_dad_kick(ifp);
3443 		spin_unlock(&ifp->lock);
3444 	}
3445 	read_unlock_bh(&idev->lock);
3446 }
3447 
3448 #ifdef CONFIG_PROC_FS
3449 struct if6_iter_state {
3450 	struct seq_net_private p;
3451 	int bucket;
3452 	int offset;
3453 };
3454 
3455 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
3456 {
3457 	struct inet6_ifaddr *ifa = NULL;
3458 	struct if6_iter_state *state = seq->private;
3459 	struct net *net = seq_file_net(seq);
3460 	int p = 0;
3461 
3462 	/* initial bucket if pos is 0 */
3463 	if (pos == 0) {
3464 		state->bucket = 0;
3465 		state->offset = 0;
3466 	}
3467 
3468 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
3469 		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
3470 					 addr_lst) {
3471 			if (!net_eq(dev_net(ifa->idev->dev), net))
3472 				continue;
3473 			/* sync with offset */
3474 			if (p < state->offset) {
3475 				p++;
3476 				continue;
3477 			}
3478 			state->offset++;
3479 			return ifa;
3480 		}
3481 
3482 		/* prepare for next bucket */
3483 		state->offset = 0;
3484 		p = 0;
3485 	}
3486 	return NULL;
3487 }
3488 
3489 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
3490 					 struct inet6_ifaddr *ifa)
3491 {
3492 	struct if6_iter_state *state = seq->private;
3493 	struct net *net = seq_file_net(seq);
3494 
3495 	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
3496 		if (!net_eq(dev_net(ifa->idev->dev), net))
3497 			continue;
3498 		state->offset++;
3499 		return ifa;
3500 	}
3501 
3502 	while (++state->bucket < IN6_ADDR_HSIZE) {
3503 		state->offset = 0;
3504 		hlist_for_each_entry_rcu_bh(ifa,
3505 				     &inet6_addr_lst[state->bucket], addr_lst) {
3506 			if (!net_eq(dev_net(ifa->idev->dev), net))
3507 				continue;
3508 			state->offset++;
3509 			return ifa;
3510 		}
3511 	}
3512 
3513 	return NULL;
3514 }
3515 
3516 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
3517 	__acquires(rcu_bh)
3518 {
3519 	rcu_read_lock_bh();
3520 	return if6_get_first(seq, *pos);
3521 }
3522 
3523 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3524 {
3525 	struct inet6_ifaddr *ifa;
3526 
3527 	ifa = if6_get_next(seq, v);
3528 	++*pos;
3529 	return ifa;
3530 }
3531 
3532 static void if6_seq_stop(struct seq_file *seq, void *v)
3533 	__releases(rcu_bh)
3534 {
3535 	rcu_read_unlock_bh();
3536 }
3537 
3538 static int if6_seq_show(struct seq_file *seq, void *v)
3539 {
3540 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
3541 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
3542 		   &ifp->addr,
3543 		   ifp->idev->dev->ifindex,
3544 		   ifp->prefix_len,
3545 		   ifp->scope,
3546 		   (u8) ifp->flags,
3547 		   ifp->idev->dev->name);
3548 	return 0;
3549 }
3550 
3551 static const struct seq_operations if6_seq_ops = {
3552 	.start	= if6_seq_start,
3553 	.next	= if6_seq_next,
3554 	.show	= if6_seq_show,
3555 	.stop	= if6_seq_stop,
3556 };
3557 
3558 static int if6_seq_open(struct inode *inode, struct file *file)
3559 {
3560 	return seq_open_net(inode, file, &if6_seq_ops,
3561 			    sizeof(struct if6_iter_state));
3562 }
3563 
3564 static const struct file_operations if6_fops = {
3565 	.owner		= THIS_MODULE,
3566 	.open		= if6_seq_open,
3567 	.read		= seq_read,
3568 	.llseek		= seq_lseek,
3569 	.release	= seq_release_net,
3570 };
3571 
3572 static int __net_init if6_proc_net_init(struct net *net)
3573 {
3574 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
3575 		return -ENOMEM;
3576 	return 0;
3577 }
3578 
3579 static void __net_exit if6_proc_net_exit(struct net *net)
3580 {
3581 	remove_proc_entry("if_inet6", net->proc_net);
3582 }
3583 
3584 static struct pernet_operations if6_proc_net_ops = {
3585 	.init = if6_proc_net_init,
3586 	.exit = if6_proc_net_exit,
3587 };
3588 
3589 int __init if6_proc_init(void)
3590 {
3591 	return register_pernet_subsys(&if6_proc_net_ops);
3592 }
3593 
3594 void if6_proc_exit(void)
3595 {
3596 	unregister_pernet_subsys(&if6_proc_net_ops);
3597 }
3598 #endif	/* CONFIG_PROC_FS */
3599 
3600 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3601 /* Check if address is a home address configured on any interface. */
3602 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
3603 {
3604 	int ret = 0;
3605 	struct inet6_ifaddr *ifp = NULL;
3606 	unsigned int hash = inet6_addr_hash(addr);
3607 
3608 	rcu_read_lock_bh();
3609 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
3610 		if (!net_eq(dev_net(ifp->idev->dev), net))
3611 			continue;
3612 		if (ipv6_addr_equal(&ifp->addr, addr) &&
3613 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
3614 			ret = 1;
3615 			break;
3616 		}
3617 	}
3618 	rcu_read_unlock_bh();
3619 	return ret;
3620 }
3621 #endif
3622 
3623 /*
3624  *	Periodic address status verification
3625  */
3626 
3627 static void addrconf_verify_rtnl(void)
3628 {
3629 	unsigned long now, next, next_sec, next_sched;
3630 	struct inet6_ifaddr *ifp;
3631 	int i;
3632 
3633 	ASSERT_RTNL();
3634 
3635 	rcu_read_lock_bh();
3636 	now = jiffies;
3637 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
3638 
3639 	cancel_delayed_work(&addr_chk_work);
3640 
3641 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3642 restart:
3643 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
3644 			unsigned long age;
3645 
3646 			/* When setting preferred_lft to a value not zero or
3647 			 * infinity, while valid_lft is infinity
3648 			 * IFA_F_PERMANENT has a non-infinity life time.
3649 			 */
3650 			if ((ifp->flags & IFA_F_PERMANENT) &&
3651 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
3652 				continue;
3653 
3654 			spin_lock(&ifp->lock);
3655 			/* We try to batch several events at once. */
3656 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
3657 
3658 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
3659 			    age >= ifp->valid_lft) {
3660 				spin_unlock(&ifp->lock);
3661 				in6_ifa_hold(ifp);
3662 				ipv6_del_addr(ifp);
3663 				goto restart;
3664 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
3665 				spin_unlock(&ifp->lock);
3666 				continue;
3667 			} else if (age >= ifp->prefered_lft) {
3668 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
3669 				int deprecate = 0;
3670 
3671 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
3672 					deprecate = 1;
3673 					ifp->flags |= IFA_F_DEPRECATED;
3674 				}
3675 
3676 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
3677 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
3678 					next = ifp->tstamp + ifp->valid_lft * HZ;
3679 
3680 				spin_unlock(&ifp->lock);
3681 
3682 				if (deprecate) {
3683 					in6_ifa_hold(ifp);
3684 
3685 					ipv6_ifa_notify(0, ifp);
3686 					in6_ifa_put(ifp);
3687 					goto restart;
3688 				}
3689 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
3690 				   !(ifp->flags&IFA_F_TENTATIVE)) {
3691 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
3692 					ifp->idev->cnf.dad_transmits *
3693 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
3694 
3695 				if (age >= ifp->prefered_lft - regen_advance) {
3696 					struct inet6_ifaddr *ifpub = ifp->ifpub;
3697 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3698 						next = ifp->tstamp + ifp->prefered_lft * HZ;
3699 					if (!ifp->regen_count && ifpub) {
3700 						ifp->regen_count++;
3701 						in6_ifa_hold(ifp);
3702 						in6_ifa_hold(ifpub);
3703 						spin_unlock(&ifp->lock);
3704 
3705 						spin_lock(&ifpub->lock);
3706 						ifpub->regen_count = 0;
3707 						spin_unlock(&ifpub->lock);
3708 						ipv6_create_tempaddr(ifpub, ifp);
3709 						in6_ifa_put(ifpub);
3710 						in6_ifa_put(ifp);
3711 						goto restart;
3712 					}
3713 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
3714 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
3715 				spin_unlock(&ifp->lock);
3716 			} else {
3717 				/* ifp->prefered_lft <= ifp->valid_lft */
3718 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3719 					next = ifp->tstamp + ifp->prefered_lft * HZ;
3720 				spin_unlock(&ifp->lock);
3721 			}
3722 		}
3723 	}
3724 
3725 	next_sec = round_jiffies_up(next);
3726 	next_sched = next;
3727 
3728 	/* If rounded timeout is accurate enough, accept it. */
3729 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
3730 		next_sched = next_sec;
3731 
3732 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
3733 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
3734 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
3735 
3736 	ADBG(KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
3737 	      now, next, next_sec, next_sched);
3738 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
3739 	rcu_read_unlock_bh();
3740 }
3741 
3742 static void addrconf_verify_work(struct work_struct *w)
3743 {
3744 	rtnl_lock();
3745 	addrconf_verify_rtnl();
3746 	rtnl_unlock();
3747 }
3748 
3749 static void addrconf_verify(void)
3750 {
3751 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
3752 }
3753 
3754 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
3755 				     struct in6_addr **peer_pfx)
3756 {
3757 	struct in6_addr *pfx = NULL;
3758 
3759 	*peer_pfx = NULL;
3760 
3761 	if (addr)
3762 		pfx = nla_data(addr);
3763 
3764 	if (local) {
3765 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
3766 			*peer_pfx = pfx;
3767 		pfx = nla_data(local);
3768 	}
3769 
3770 	return pfx;
3771 }
3772 
3773 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
3774 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
3775 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
3776 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
3777 	[IFA_FLAGS]		= { .len = sizeof(u32) },
3778 };
3779 
3780 static int
3781 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
3782 {
3783 	struct net *net = sock_net(skb->sk);
3784 	struct ifaddrmsg *ifm;
3785 	struct nlattr *tb[IFA_MAX+1];
3786 	struct in6_addr *pfx, *peer_pfx;
3787 	u32 ifa_flags;
3788 	int err;
3789 
3790 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3791 	if (err < 0)
3792 		return err;
3793 
3794 	ifm = nlmsg_data(nlh);
3795 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
3796 	if (pfx == NULL)
3797 		return -EINVAL;
3798 
3799 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
3800 
3801 	/* We ignore other flags so far. */
3802 	ifa_flags &= IFA_F_MANAGETEMPADDR;
3803 
3804 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
3805 			      ifm->ifa_prefixlen);
3806 }
3807 
3808 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags,
3809 			     u32 prefered_lft, u32 valid_lft)
3810 {
3811 	u32 flags;
3812 	clock_t expires;
3813 	unsigned long timeout;
3814 	bool was_managetempaddr;
3815 	bool had_prefixroute;
3816 
3817 	ASSERT_RTNL();
3818 
3819 	if (!valid_lft || (prefered_lft > valid_lft))
3820 		return -EINVAL;
3821 
3822 	if (ifa_flags & IFA_F_MANAGETEMPADDR &&
3823 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
3824 		return -EINVAL;
3825 
3826 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
3827 	if (addrconf_finite_timeout(timeout)) {
3828 		expires = jiffies_to_clock_t(timeout * HZ);
3829 		valid_lft = timeout;
3830 		flags = RTF_EXPIRES;
3831 	} else {
3832 		expires = 0;
3833 		flags = 0;
3834 		ifa_flags |= IFA_F_PERMANENT;
3835 	}
3836 
3837 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
3838 	if (addrconf_finite_timeout(timeout)) {
3839 		if (timeout == 0)
3840 			ifa_flags |= IFA_F_DEPRECATED;
3841 		prefered_lft = timeout;
3842 	}
3843 
3844 	spin_lock_bh(&ifp->lock);
3845 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
3846 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
3847 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
3848 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
3849 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
3850 			IFA_F_NOPREFIXROUTE);
3851 	ifp->flags |= ifa_flags;
3852 	ifp->tstamp = jiffies;
3853 	ifp->valid_lft = valid_lft;
3854 	ifp->prefered_lft = prefered_lft;
3855 
3856 	spin_unlock_bh(&ifp->lock);
3857 	if (!(ifp->flags&IFA_F_TENTATIVE))
3858 		ipv6_ifa_notify(0, ifp);
3859 
3860 	if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
3861 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
3862 				      expires, flags);
3863 	} else if (had_prefixroute) {
3864 		enum cleanup_prefix_rt_t action;
3865 		unsigned long rt_expires;
3866 
3867 		write_lock_bh(&ifp->idev->lock);
3868 		action = check_cleanup_prefix_route(ifp, &rt_expires);
3869 		write_unlock_bh(&ifp->idev->lock);
3870 
3871 		if (action != CLEANUP_PREFIX_RT_NOP) {
3872 			cleanup_prefix_route(ifp, rt_expires,
3873 				action == CLEANUP_PREFIX_RT_DEL);
3874 		}
3875 	}
3876 
3877 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
3878 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
3879 			valid_lft = prefered_lft = 0;
3880 		manage_tempaddrs(ifp->idev, ifp, valid_lft, prefered_lft,
3881 				 !was_managetempaddr, jiffies);
3882 	}
3883 
3884 	addrconf_verify_rtnl();
3885 
3886 	return 0;
3887 }
3888 
3889 static int
3890 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
3891 {
3892 	struct net *net = sock_net(skb->sk);
3893 	struct ifaddrmsg *ifm;
3894 	struct nlattr *tb[IFA_MAX+1];
3895 	struct in6_addr *pfx, *peer_pfx;
3896 	struct inet6_ifaddr *ifa;
3897 	struct net_device *dev;
3898 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
3899 	u32 ifa_flags;
3900 	int err;
3901 
3902 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3903 	if (err < 0)
3904 		return err;
3905 
3906 	ifm = nlmsg_data(nlh);
3907 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
3908 	if (pfx == NULL)
3909 		return -EINVAL;
3910 
3911 	if (tb[IFA_CACHEINFO]) {
3912 		struct ifa_cacheinfo *ci;
3913 
3914 		ci = nla_data(tb[IFA_CACHEINFO]);
3915 		valid_lft = ci->ifa_valid;
3916 		preferred_lft = ci->ifa_prefered;
3917 	} else {
3918 		preferred_lft = INFINITY_LIFE_TIME;
3919 		valid_lft = INFINITY_LIFE_TIME;
3920 	}
3921 
3922 	dev =  __dev_get_by_index(net, ifm->ifa_index);
3923 	if (dev == NULL)
3924 		return -ENODEV;
3925 
3926 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
3927 
3928 	/* We ignore other flags so far. */
3929 	ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
3930 		     IFA_F_NOPREFIXROUTE;
3931 
3932 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
3933 	if (ifa == NULL) {
3934 		/*
3935 		 * It would be best to check for !NLM_F_CREATE here but
3936 		 * userspace already relies on not having to provide this.
3937 		 */
3938 		return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,
3939 				      ifm->ifa_prefixlen, ifa_flags,
3940 				      preferred_lft, valid_lft);
3941 	}
3942 
3943 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
3944 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
3945 		err = -EEXIST;
3946 	else
3947 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
3948 
3949 	in6_ifa_put(ifa);
3950 
3951 	return err;
3952 }
3953 
3954 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
3955 			  u8 scope, int ifindex)
3956 {
3957 	struct ifaddrmsg *ifm;
3958 
3959 	ifm = nlmsg_data(nlh);
3960 	ifm->ifa_family = AF_INET6;
3961 	ifm->ifa_prefixlen = prefixlen;
3962 	ifm->ifa_flags = flags;
3963 	ifm->ifa_scope = scope;
3964 	ifm->ifa_index = ifindex;
3965 }
3966 
3967 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
3968 			 unsigned long tstamp, u32 preferred, u32 valid)
3969 {
3970 	struct ifa_cacheinfo ci;
3971 
3972 	ci.cstamp = cstamp_delta(cstamp);
3973 	ci.tstamp = cstamp_delta(tstamp);
3974 	ci.ifa_prefered = preferred;
3975 	ci.ifa_valid = valid;
3976 
3977 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
3978 }
3979 
3980 static inline int rt_scope(int ifa_scope)
3981 {
3982 	if (ifa_scope & IFA_HOST)
3983 		return RT_SCOPE_HOST;
3984 	else if (ifa_scope & IFA_LINK)
3985 		return RT_SCOPE_LINK;
3986 	else if (ifa_scope & IFA_SITE)
3987 		return RT_SCOPE_SITE;
3988 	else
3989 		return RT_SCOPE_UNIVERSE;
3990 }
3991 
3992 static inline int inet6_ifaddr_msgsize(void)
3993 {
3994 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
3995 	       + nla_total_size(16) /* IFA_LOCAL */
3996 	       + nla_total_size(16) /* IFA_ADDRESS */
3997 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
3998 	       + nla_total_size(4)  /* IFA_FLAGS */;
3999 }
4000 
4001 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4002 			     u32 portid, u32 seq, int event, unsigned int flags)
4003 {
4004 	struct nlmsghdr  *nlh;
4005 	u32 preferred, valid;
4006 
4007 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4008 	if (nlh == NULL)
4009 		return -EMSGSIZE;
4010 
4011 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4012 		      ifa->idev->dev->ifindex);
4013 
4014 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4015 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4016 		preferred = ifa->prefered_lft;
4017 		valid = ifa->valid_lft;
4018 		if (preferred != INFINITY_LIFE_TIME) {
4019 			long tval = (jiffies - ifa->tstamp)/HZ;
4020 			if (preferred > tval)
4021 				preferred -= tval;
4022 			else
4023 				preferred = 0;
4024 			if (valid != INFINITY_LIFE_TIME) {
4025 				if (valid > tval)
4026 					valid -= tval;
4027 				else
4028 					valid = 0;
4029 			}
4030 		}
4031 	} else {
4032 		preferred = INFINITY_LIFE_TIME;
4033 		valid = INFINITY_LIFE_TIME;
4034 	}
4035 
4036 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4037 		if (nla_put(skb, IFA_LOCAL, 16, &ifa->addr) < 0 ||
4038 		    nla_put(skb, IFA_ADDRESS, 16, &ifa->peer_addr) < 0)
4039 			goto error;
4040 	} else
4041 		if (nla_put(skb, IFA_ADDRESS, 16, &ifa->addr) < 0)
4042 			goto error;
4043 
4044 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4045 		goto error;
4046 
4047 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4048 		goto error;
4049 
4050 	return nlmsg_end(skb, nlh);
4051 
4052 error:
4053 	nlmsg_cancel(skb, nlh);
4054 	return -EMSGSIZE;
4055 }
4056 
4057 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4058 				u32 portid, u32 seq, int event, u16 flags)
4059 {
4060 	struct nlmsghdr  *nlh;
4061 	u8 scope = RT_SCOPE_UNIVERSE;
4062 	int ifindex = ifmca->idev->dev->ifindex;
4063 
4064 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4065 		scope = RT_SCOPE_SITE;
4066 
4067 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4068 	if (nlh == NULL)
4069 		return -EMSGSIZE;
4070 
4071 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4072 	if (nla_put(skb, IFA_MULTICAST, 16, &ifmca->mca_addr) < 0 ||
4073 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4074 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4075 		nlmsg_cancel(skb, nlh);
4076 		return -EMSGSIZE;
4077 	}
4078 
4079 	return nlmsg_end(skb, nlh);
4080 }
4081 
4082 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4083 				u32 portid, u32 seq, int event, unsigned int flags)
4084 {
4085 	struct nlmsghdr  *nlh;
4086 	u8 scope = RT_SCOPE_UNIVERSE;
4087 	int ifindex = ifaca->aca_idev->dev->ifindex;
4088 
4089 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4090 		scope = RT_SCOPE_SITE;
4091 
4092 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4093 	if (nlh == NULL)
4094 		return -EMSGSIZE;
4095 
4096 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4097 	if (nla_put(skb, IFA_ANYCAST, 16, &ifaca->aca_addr) < 0 ||
4098 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4099 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4100 		nlmsg_cancel(skb, nlh);
4101 		return -EMSGSIZE;
4102 	}
4103 
4104 	return nlmsg_end(skb, nlh);
4105 }
4106 
4107 enum addr_type_t {
4108 	UNICAST_ADDR,
4109 	MULTICAST_ADDR,
4110 	ANYCAST_ADDR,
4111 };
4112 
4113 /* called with rcu_read_lock() */
4114 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4115 			  struct netlink_callback *cb, enum addr_type_t type,
4116 			  int s_ip_idx, int *p_ip_idx)
4117 {
4118 	struct ifmcaddr6 *ifmca;
4119 	struct ifacaddr6 *ifaca;
4120 	int err = 1;
4121 	int ip_idx = *p_ip_idx;
4122 
4123 	read_lock_bh(&idev->lock);
4124 	switch (type) {
4125 	case UNICAST_ADDR: {
4126 		struct inet6_ifaddr *ifa;
4127 
4128 		/* unicast address incl. temp addr */
4129 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4130 			if (++ip_idx < s_ip_idx)
4131 				continue;
4132 			err = inet6_fill_ifaddr(skb, ifa,
4133 						NETLINK_CB(cb->skb).portid,
4134 						cb->nlh->nlmsg_seq,
4135 						RTM_NEWADDR,
4136 						NLM_F_MULTI);
4137 			if (err <= 0)
4138 				break;
4139 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4140 		}
4141 		break;
4142 	}
4143 	case MULTICAST_ADDR:
4144 		/* multicast address */
4145 		for (ifmca = idev->mc_list; ifmca;
4146 		     ifmca = ifmca->next, ip_idx++) {
4147 			if (ip_idx < s_ip_idx)
4148 				continue;
4149 			err = inet6_fill_ifmcaddr(skb, ifmca,
4150 						  NETLINK_CB(cb->skb).portid,
4151 						  cb->nlh->nlmsg_seq,
4152 						  RTM_GETMULTICAST,
4153 						  NLM_F_MULTI);
4154 			if (err <= 0)
4155 				break;
4156 		}
4157 		break;
4158 	case ANYCAST_ADDR:
4159 		/* anycast address */
4160 		for (ifaca = idev->ac_list; ifaca;
4161 		     ifaca = ifaca->aca_next, ip_idx++) {
4162 			if (ip_idx < s_ip_idx)
4163 				continue;
4164 			err = inet6_fill_ifacaddr(skb, ifaca,
4165 						  NETLINK_CB(cb->skb).portid,
4166 						  cb->nlh->nlmsg_seq,
4167 						  RTM_GETANYCAST,
4168 						  NLM_F_MULTI);
4169 			if (err <= 0)
4170 				break;
4171 		}
4172 		break;
4173 	default:
4174 		break;
4175 	}
4176 	read_unlock_bh(&idev->lock);
4177 	*p_ip_idx = ip_idx;
4178 	return err;
4179 }
4180 
4181 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
4182 			   enum addr_type_t type)
4183 {
4184 	struct net *net = sock_net(skb->sk);
4185 	int h, s_h;
4186 	int idx, ip_idx;
4187 	int s_idx, s_ip_idx;
4188 	struct net_device *dev;
4189 	struct inet6_dev *idev;
4190 	struct hlist_head *head;
4191 
4192 	s_h = cb->args[0];
4193 	s_idx = idx = cb->args[1];
4194 	s_ip_idx = ip_idx = cb->args[2];
4195 
4196 	rcu_read_lock();
4197 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
4198 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4199 		idx = 0;
4200 		head = &net->dev_index_head[h];
4201 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4202 			if (idx < s_idx)
4203 				goto cont;
4204 			if (h > s_h || idx > s_idx)
4205 				s_ip_idx = 0;
4206 			ip_idx = 0;
4207 			idev = __in6_dev_get(dev);
4208 			if (!idev)
4209 				goto cont;
4210 
4211 			if (in6_dump_addrs(idev, skb, cb, type,
4212 					   s_ip_idx, &ip_idx) <= 0)
4213 				goto done;
4214 cont:
4215 			idx++;
4216 		}
4217 	}
4218 done:
4219 	rcu_read_unlock();
4220 	cb->args[0] = h;
4221 	cb->args[1] = idx;
4222 	cb->args[2] = ip_idx;
4223 
4224 	return skb->len;
4225 }
4226 
4227 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
4228 {
4229 	enum addr_type_t type = UNICAST_ADDR;
4230 
4231 	return inet6_dump_addr(skb, cb, type);
4232 }
4233 
4234 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
4235 {
4236 	enum addr_type_t type = MULTICAST_ADDR;
4237 
4238 	return inet6_dump_addr(skb, cb, type);
4239 }
4240 
4241 
4242 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
4243 {
4244 	enum addr_type_t type = ANYCAST_ADDR;
4245 
4246 	return inet6_dump_addr(skb, cb, type);
4247 }
4248 
4249 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh)
4250 {
4251 	struct net *net = sock_net(in_skb->sk);
4252 	struct ifaddrmsg *ifm;
4253 	struct nlattr *tb[IFA_MAX+1];
4254 	struct in6_addr *addr = NULL, *peer;
4255 	struct net_device *dev = NULL;
4256 	struct inet6_ifaddr *ifa;
4257 	struct sk_buff *skb;
4258 	int err;
4259 
4260 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
4261 	if (err < 0)
4262 		goto errout;
4263 
4264 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
4265 	if (addr == NULL) {
4266 		err = -EINVAL;
4267 		goto errout;
4268 	}
4269 
4270 	ifm = nlmsg_data(nlh);
4271 	if (ifm->ifa_index)
4272 		dev = __dev_get_by_index(net, ifm->ifa_index);
4273 
4274 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
4275 	if (!ifa) {
4276 		err = -EADDRNOTAVAIL;
4277 		goto errout;
4278 	}
4279 
4280 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
4281 	if (!skb) {
4282 		err = -ENOBUFS;
4283 		goto errout_ifa;
4284 	}
4285 
4286 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
4287 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
4288 	if (err < 0) {
4289 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4290 		WARN_ON(err == -EMSGSIZE);
4291 		kfree_skb(skb);
4292 		goto errout_ifa;
4293 	}
4294 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
4295 errout_ifa:
4296 	in6_ifa_put(ifa);
4297 errout:
4298 	return err;
4299 }
4300 
4301 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
4302 {
4303 	struct sk_buff *skb;
4304 	struct net *net = dev_net(ifa->idev->dev);
4305 	int err = -ENOBUFS;
4306 
4307 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
4308 	if (skb == NULL)
4309 		goto errout;
4310 
4311 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
4312 	if (err < 0) {
4313 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4314 		WARN_ON(err == -EMSGSIZE);
4315 		kfree_skb(skb);
4316 		goto errout;
4317 	}
4318 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
4319 	return;
4320 errout:
4321 	if (err < 0)
4322 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
4323 }
4324 
4325 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
4326 				__s32 *array, int bytes)
4327 {
4328 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4329 
4330 	memset(array, 0, bytes);
4331 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4332 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4333 	array[DEVCONF_MTU6] = cnf->mtu6;
4334 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4335 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4336 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4337 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4338 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4339 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
4340 		jiffies_to_msecs(cnf->rtr_solicit_interval);
4341 	array[DEVCONF_RTR_SOLICIT_DELAY] =
4342 		jiffies_to_msecs(cnf->rtr_solicit_delay);
4343 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
4344 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
4345 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
4346 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
4347 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
4348 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
4349 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
4350 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
4351 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
4352 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
4353 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
4354 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
4355 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
4356 #ifdef CONFIG_IPV6_ROUTER_PREF
4357 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
4358 	array[DEVCONF_RTR_PROBE_INTERVAL] =
4359 		jiffies_to_msecs(cnf->rtr_probe_interval);
4360 #ifdef CONFIG_IPV6_ROUTE_INFO
4361 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
4362 #endif
4363 #endif
4364 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
4365 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
4366 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4367 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
4368 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
4369 #endif
4370 #ifdef CONFIG_IPV6_MROUTE
4371 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
4372 #endif
4373 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
4374 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
4375 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
4376 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
4377 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
4378 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
4379 }
4380 
4381 static inline size_t inet6_ifla6_size(void)
4382 {
4383 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
4384 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
4385 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
4386 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
4387 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
4388 	     + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */
4389 }
4390 
4391 static inline size_t inet6_if_nlmsg_size(void)
4392 {
4393 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
4394 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
4395 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
4396 	       + nla_total_size(4) /* IFLA_MTU */
4397 	       + nla_total_size(4) /* IFLA_LINK */
4398 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
4399 }
4400 
4401 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
4402 				      int items, int bytes)
4403 {
4404 	int i;
4405 	int pad = bytes - sizeof(u64) * items;
4406 	BUG_ON(pad < 0);
4407 
4408 	/* Use put_unaligned() because stats may not be aligned for u64. */
4409 	put_unaligned(items, &stats[0]);
4410 	for (i = 1; i < items; i++)
4411 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
4412 
4413 	memset(&stats[items], 0, pad);
4414 }
4415 
4416 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
4417 				      int items, int bytes, size_t syncpoff)
4418 {
4419 	int i;
4420 	int pad = bytes - sizeof(u64) * items;
4421 	BUG_ON(pad < 0);
4422 
4423 	/* Use put_unaligned() because stats may not be aligned for u64. */
4424 	put_unaligned(items, &stats[0]);
4425 	for (i = 1; i < items; i++)
4426 		put_unaligned(snmp_fold_field64(mib, i, syncpoff), &stats[i]);
4427 
4428 	memset(&stats[items], 0, pad);
4429 }
4430 
4431 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
4432 			     int bytes)
4433 {
4434 	switch (attrtype) {
4435 	case IFLA_INET6_STATS:
4436 		__snmp6_fill_stats64(stats, idev->stats.ipv6,
4437 				     IPSTATS_MIB_MAX, bytes, offsetof(struct ipstats_mib, syncp));
4438 		break;
4439 	case IFLA_INET6_ICMP6STATS:
4440 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, ICMP6_MIB_MAX, bytes);
4441 		break;
4442 	}
4443 }
4444 
4445 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev)
4446 {
4447 	struct nlattr *nla;
4448 	struct ifla_cacheinfo ci;
4449 
4450 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
4451 		goto nla_put_failure;
4452 	ci.max_reasm_len = IPV6_MAXPLEN;
4453 	ci.tstamp = cstamp_delta(idev->tstamp);
4454 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
4455 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
4456 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
4457 		goto nla_put_failure;
4458 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
4459 	if (nla == NULL)
4460 		goto nla_put_failure;
4461 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
4462 
4463 	/* XXX - MC not implemented */
4464 
4465 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
4466 	if (nla == NULL)
4467 		goto nla_put_failure;
4468 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
4469 
4470 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
4471 	if (nla == NULL)
4472 		goto nla_put_failure;
4473 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
4474 
4475 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
4476 	if (nla == NULL)
4477 		goto nla_put_failure;
4478 
4479 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->addr_gen_mode))
4480 		goto nla_put_failure;
4481 
4482 	read_lock_bh(&idev->lock);
4483 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
4484 	read_unlock_bh(&idev->lock);
4485 
4486 	return 0;
4487 
4488 nla_put_failure:
4489 	return -EMSGSIZE;
4490 }
4491 
4492 static size_t inet6_get_link_af_size(const struct net_device *dev)
4493 {
4494 	if (!__in6_dev_get(dev))
4495 		return 0;
4496 
4497 	return inet6_ifla6_size();
4498 }
4499 
4500 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
4501 {
4502 	struct inet6_dev *idev = __in6_dev_get(dev);
4503 
4504 	if (!idev)
4505 		return -ENODATA;
4506 
4507 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4508 		return -EMSGSIZE;
4509 
4510 	return 0;
4511 }
4512 
4513 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
4514 {
4515 	struct inet6_ifaddr *ifp;
4516 	struct net_device *dev = idev->dev;
4517 	bool update_rs = false;
4518 	struct in6_addr ll_addr;
4519 
4520 	ASSERT_RTNL();
4521 
4522 	if (token == NULL)
4523 		return -EINVAL;
4524 	if (ipv6_addr_any(token))
4525 		return -EINVAL;
4526 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
4527 		return -EINVAL;
4528 	if (!ipv6_accept_ra(idev))
4529 		return -EINVAL;
4530 	if (idev->cnf.rtr_solicits <= 0)
4531 		return -EINVAL;
4532 
4533 	write_lock_bh(&idev->lock);
4534 
4535 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
4536 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
4537 
4538 	write_unlock_bh(&idev->lock);
4539 
4540 	if (!idev->dead && (idev->if_flags & IF_READY) &&
4541 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
4542 			     IFA_F_OPTIMISTIC)) {
4543 
4544 		/* If we're not ready, then normal ifup will take care
4545 		 * of this. Otherwise, we need to request our rs here.
4546 		 */
4547 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
4548 		update_rs = true;
4549 	}
4550 
4551 	write_lock_bh(&idev->lock);
4552 
4553 	if (update_rs) {
4554 		idev->if_flags |= IF_RS_SENT;
4555 		idev->rs_probes = 1;
4556 		addrconf_mod_rs_timer(idev, idev->cnf.rtr_solicit_interval);
4557 	}
4558 
4559 	/* Well, that's kinda nasty ... */
4560 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4561 		spin_lock(&ifp->lock);
4562 		if (ifp->tokenized) {
4563 			ifp->valid_lft = 0;
4564 			ifp->prefered_lft = 0;
4565 		}
4566 		spin_unlock(&ifp->lock);
4567 	}
4568 
4569 	write_unlock_bh(&idev->lock);
4570 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
4571 	addrconf_verify_rtnl();
4572 	return 0;
4573 }
4574 
4575 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
4576 {
4577 	int err = -EINVAL;
4578 	struct inet6_dev *idev = __in6_dev_get(dev);
4579 	struct nlattr *tb[IFLA_INET6_MAX + 1];
4580 
4581 	if (!idev)
4582 		return -EAFNOSUPPORT;
4583 
4584 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL) < 0)
4585 		BUG();
4586 
4587 	if (tb[IFLA_INET6_TOKEN]) {
4588 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
4589 		if (err)
4590 			return err;
4591 	}
4592 
4593 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
4594 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
4595 
4596 		if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
4597 		    mode != IN6_ADDR_GEN_MODE_NONE)
4598 			return -EINVAL;
4599 		idev->addr_gen_mode = mode;
4600 		err = 0;
4601 	}
4602 
4603 	return err;
4604 }
4605 
4606 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
4607 			     u32 portid, u32 seq, int event, unsigned int flags)
4608 {
4609 	struct net_device *dev = idev->dev;
4610 	struct ifinfomsg *hdr;
4611 	struct nlmsghdr *nlh;
4612 	void *protoinfo;
4613 
4614 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
4615 	if (nlh == NULL)
4616 		return -EMSGSIZE;
4617 
4618 	hdr = nlmsg_data(nlh);
4619 	hdr->ifi_family = AF_INET6;
4620 	hdr->__ifi_pad = 0;
4621 	hdr->ifi_type = dev->type;
4622 	hdr->ifi_index = dev->ifindex;
4623 	hdr->ifi_flags = dev_get_flags(dev);
4624 	hdr->ifi_change = 0;
4625 
4626 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
4627 	    (dev->addr_len &&
4628 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
4629 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
4630 	    (dev->ifindex != dev->iflink &&
4631 	     nla_put_u32(skb, IFLA_LINK, dev->iflink)))
4632 		goto nla_put_failure;
4633 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
4634 	if (protoinfo == NULL)
4635 		goto nla_put_failure;
4636 
4637 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4638 		goto nla_put_failure;
4639 
4640 	nla_nest_end(skb, protoinfo);
4641 	return nlmsg_end(skb, nlh);
4642 
4643 nla_put_failure:
4644 	nlmsg_cancel(skb, nlh);
4645 	return -EMSGSIZE;
4646 }
4647 
4648 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
4649 {
4650 	struct net *net = sock_net(skb->sk);
4651 	int h, s_h;
4652 	int idx = 0, s_idx;
4653 	struct net_device *dev;
4654 	struct inet6_dev *idev;
4655 	struct hlist_head *head;
4656 
4657 	s_h = cb->args[0];
4658 	s_idx = cb->args[1];
4659 
4660 	rcu_read_lock();
4661 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4662 		idx = 0;
4663 		head = &net->dev_index_head[h];
4664 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4665 			if (idx < s_idx)
4666 				goto cont;
4667 			idev = __in6_dev_get(dev);
4668 			if (!idev)
4669 				goto cont;
4670 			if (inet6_fill_ifinfo(skb, idev,
4671 					      NETLINK_CB(cb->skb).portid,
4672 					      cb->nlh->nlmsg_seq,
4673 					      RTM_NEWLINK, NLM_F_MULTI) <= 0)
4674 				goto out;
4675 cont:
4676 			idx++;
4677 		}
4678 	}
4679 out:
4680 	rcu_read_unlock();
4681 	cb->args[1] = idx;
4682 	cb->args[0] = h;
4683 
4684 	return skb->len;
4685 }
4686 
4687 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
4688 {
4689 	struct sk_buff *skb;
4690 	struct net *net = dev_net(idev->dev);
4691 	int err = -ENOBUFS;
4692 
4693 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
4694 	if (skb == NULL)
4695 		goto errout;
4696 
4697 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
4698 	if (err < 0) {
4699 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
4700 		WARN_ON(err == -EMSGSIZE);
4701 		kfree_skb(skb);
4702 		goto errout;
4703 	}
4704 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
4705 	return;
4706 errout:
4707 	if (err < 0)
4708 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
4709 }
4710 
4711 static inline size_t inet6_prefix_nlmsg_size(void)
4712 {
4713 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
4714 	       + nla_total_size(sizeof(struct in6_addr))
4715 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
4716 }
4717 
4718 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
4719 			     struct prefix_info *pinfo, u32 portid, u32 seq,
4720 			     int event, unsigned int flags)
4721 {
4722 	struct prefixmsg *pmsg;
4723 	struct nlmsghdr *nlh;
4724 	struct prefix_cacheinfo	ci;
4725 
4726 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
4727 	if (nlh == NULL)
4728 		return -EMSGSIZE;
4729 
4730 	pmsg = nlmsg_data(nlh);
4731 	pmsg->prefix_family = AF_INET6;
4732 	pmsg->prefix_pad1 = 0;
4733 	pmsg->prefix_pad2 = 0;
4734 	pmsg->prefix_ifindex = idev->dev->ifindex;
4735 	pmsg->prefix_len = pinfo->prefix_len;
4736 	pmsg->prefix_type = pinfo->type;
4737 	pmsg->prefix_pad3 = 0;
4738 	pmsg->prefix_flags = 0;
4739 	if (pinfo->onlink)
4740 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
4741 	if (pinfo->autoconf)
4742 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
4743 
4744 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
4745 		goto nla_put_failure;
4746 	ci.preferred_time = ntohl(pinfo->prefered);
4747 	ci.valid_time = ntohl(pinfo->valid);
4748 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
4749 		goto nla_put_failure;
4750 	return nlmsg_end(skb, nlh);
4751 
4752 nla_put_failure:
4753 	nlmsg_cancel(skb, nlh);
4754 	return -EMSGSIZE;
4755 }
4756 
4757 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
4758 			 struct prefix_info *pinfo)
4759 {
4760 	struct sk_buff *skb;
4761 	struct net *net = dev_net(idev->dev);
4762 	int err = -ENOBUFS;
4763 
4764 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
4765 	if (skb == NULL)
4766 		goto errout;
4767 
4768 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
4769 	if (err < 0) {
4770 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
4771 		WARN_ON(err == -EMSGSIZE);
4772 		kfree_skb(skb);
4773 		goto errout;
4774 	}
4775 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
4776 	return;
4777 errout:
4778 	if (err < 0)
4779 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
4780 }
4781 
4782 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4783 {
4784 	struct net *net = dev_net(ifp->idev->dev);
4785 
4786 	if (event)
4787 		ASSERT_RTNL();
4788 
4789 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
4790 
4791 	switch (event) {
4792 	case RTM_NEWADDR:
4793 		/*
4794 		 * If the address was optimistic
4795 		 * we inserted the route at the start of
4796 		 * our DAD process, so we don't need
4797 		 * to do it again
4798 		 */
4799 		if (!(ifp->rt->rt6i_node))
4800 			ip6_ins_rt(ifp->rt);
4801 		if (ifp->idev->cnf.forwarding)
4802 			addrconf_join_anycast(ifp);
4803 		if (!ipv6_addr_any(&ifp->peer_addr))
4804 			addrconf_prefix_route(&ifp->peer_addr, 128,
4805 					      ifp->idev->dev, 0, 0);
4806 		break;
4807 	case RTM_DELADDR:
4808 		if (ifp->idev->cnf.forwarding)
4809 			addrconf_leave_anycast(ifp);
4810 		addrconf_leave_solict(ifp->idev, &ifp->addr);
4811 		if (!ipv6_addr_any(&ifp->peer_addr)) {
4812 			struct rt6_info *rt;
4813 
4814 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
4815 						       ifp->idev->dev, 0, 0);
4816 			if (rt && ip6_del_rt(rt))
4817 				dst_free(&rt->dst);
4818 		}
4819 		dst_hold(&ifp->rt->dst);
4820 
4821 		if (ip6_del_rt(ifp->rt))
4822 			dst_free(&ifp->rt->dst);
4823 
4824 		rt_genid_bump_ipv6(net);
4825 		break;
4826 	}
4827 	atomic_inc(&net->ipv6.dev_addr_genid);
4828 }
4829 
4830 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4831 {
4832 	rcu_read_lock_bh();
4833 	if (likely(ifp->idev->dead == 0))
4834 		__ipv6_ifa_notify(event, ifp);
4835 	rcu_read_unlock_bh();
4836 }
4837 
4838 #ifdef CONFIG_SYSCTL
4839 
4840 static
4841 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
4842 			   void __user *buffer, size_t *lenp, loff_t *ppos)
4843 {
4844 	int *valp = ctl->data;
4845 	int val = *valp;
4846 	loff_t pos = *ppos;
4847 	struct ctl_table lctl;
4848 	int ret;
4849 
4850 	/*
4851 	 * ctl->data points to idev->cnf.forwarding, we should
4852 	 * not modify it until we get the rtnl lock.
4853 	 */
4854 	lctl = *ctl;
4855 	lctl.data = &val;
4856 
4857 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4858 
4859 	if (write)
4860 		ret = addrconf_fixup_forwarding(ctl, valp, val);
4861 	if (ret)
4862 		*ppos = pos;
4863 	return ret;
4864 }
4865 
4866 static void dev_disable_change(struct inet6_dev *idev)
4867 {
4868 	struct netdev_notifier_info info;
4869 
4870 	if (!idev || !idev->dev)
4871 		return;
4872 
4873 	netdev_notifier_info_init(&info, idev->dev);
4874 	if (idev->cnf.disable_ipv6)
4875 		addrconf_notify(NULL, NETDEV_DOWN, &info);
4876 	else
4877 		addrconf_notify(NULL, NETDEV_UP, &info);
4878 }
4879 
4880 static void addrconf_disable_change(struct net *net, __s32 newf)
4881 {
4882 	struct net_device *dev;
4883 	struct inet6_dev *idev;
4884 
4885 	rcu_read_lock();
4886 	for_each_netdev_rcu(net, dev) {
4887 		idev = __in6_dev_get(dev);
4888 		if (idev) {
4889 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
4890 			idev->cnf.disable_ipv6 = newf;
4891 			if (changed)
4892 				dev_disable_change(idev);
4893 		}
4894 	}
4895 	rcu_read_unlock();
4896 }
4897 
4898 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
4899 {
4900 	struct net *net;
4901 	int old;
4902 
4903 	if (!rtnl_trylock())
4904 		return restart_syscall();
4905 
4906 	net = (struct net *)table->extra2;
4907 	old = *p;
4908 	*p = newf;
4909 
4910 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
4911 		rtnl_unlock();
4912 		return 0;
4913 	}
4914 
4915 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
4916 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
4917 		addrconf_disable_change(net, newf);
4918 	} else if ((!newf) ^ (!old))
4919 		dev_disable_change((struct inet6_dev *)table->extra1);
4920 
4921 	rtnl_unlock();
4922 	return 0;
4923 }
4924 
4925 static
4926 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
4927 			    void __user *buffer, size_t *lenp, loff_t *ppos)
4928 {
4929 	int *valp = ctl->data;
4930 	int val = *valp;
4931 	loff_t pos = *ppos;
4932 	struct ctl_table lctl;
4933 	int ret;
4934 
4935 	/*
4936 	 * ctl->data points to idev->cnf.disable_ipv6, we should
4937 	 * not modify it until we get the rtnl lock.
4938 	 */
4939 	lctl = *ctl;
4940 	lctl.data = &val;
4941 
4942 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4943 
4944 	if (write)
4945 		ret = addrconf_disable_ipv6(ctl, valp, val);
4946 	if (ret)
4947 		*ppos = pos;
4948 	return ret;
4949 }
4950 
4951 static
4952 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
4953 			      void __user *buffer, size_t *lenp, loff_t *ppos)
4954 {
4955 	int *valp = ctl->data;
4956 	int ret;
4957 	int old, new;
4958 
4959 	old = *valp;
4960 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
4961 	new = *valp;
4962 
4963 	if (write && old != new) {
4964 		struct net *net = ctl->extra2;
4965 
4966 		if (!rtnl_trylock())
4967 			return restart_syscall();
4968 
4969 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
4970 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
4971 						     NETCONFA_IFINDEX_DEFAULT,
4972 						     net->ipv6.devconf_dflt);
4973 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
4974 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
4975 						     NETCONFA_IFINDEX_ALL,
4976 						     net->ipv6.devconf_all);
4977 		else {
4978 			struct inet6_dev *idev = ctl->extra1;
4979 
4980 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
4981 						     idev->dev->ifindex,
4982 						     &idev->cnf);
4983 		}
4984 		rtnl_unlock();
4985 	}
4986 
4987 	return ret;
4988 }
4989 
4990 
4991 static struct addrconf_sysctl_table
4992 {
4993 	struct ctl_table_header *sysctl_header;
4994 	struct ctl_table addrconf_vars[DEVCONF_MAX+1];
4995 } addrconf_sysctl __read_mostly = {
4996 	.sysctl_header = NULL,
4997 	.addrconf_vars = {
4998 		{
4999 			.procname	= "forwarding",
5000 			.data		= &ipv6_devconf.forwarding,
5001 			.maxlen		= sizeof(int),
5002 			.mode		= 0644,
5003 			.proc_handler	= addrconf_sysctl_forward,
5004 		},
5005 		{
5006 			.procname	= "hop_limit",
5007 			.data		= &ipv6_devconf.hop_limit,
5008 			.maxlen		= sizeof(int),
5009 			.mode		= 0644,
5010 			.proc_handler	= proc_dointvec,
5011 		},
5012 		{
5013 			.procname	= "mtu",
5014 			.data		= &ipv6_devconf.mtu6,
5015 			.maxlen		= sizeof(int),
5016 			.mode		= 0644,
5017 			.proc_handler	= proc_dointvec,
5018 		},
5019 		{
5020 			.procname	= "accept_ra",
5021 			.data		= &ipv6_devconf.accept_ra,
5022 			.maxlen		= sizeof(int),
5023 			.mode		= 0644,
5024 			.proc_handler	= proc_dointvec,
5025 		},
5026 		{
5027 			.procname	= "accept_redirects",
5028 			.data		= &ipv6_devconf.accept_redirects,
5029 			.maxlen		= sizeof(int),
5030 			.mode		= 0644,
5031 			.proc_handler	= proc_dointvec,
5032 		},
5033 		{
5034 			.procname	= "autoconf",
5035 			.data		= &ipv6_devconf.autoconf,
5036 			.maxlen		= sizeof(int),
5037 			.mode		= 0644,
5038 			.proc_handler	= proc_dointvec,
5039 		},
5040 		{
5041 			.procname	= "dad_transmits",
5042 			.data		= &ipv6_devconf.dad_transmits,
5043 			.maxlen		= sizeof(int),
5044 			.mode		= 0644,
5045 			.proc_handler	= proc_dointvec,
5046 		},
5047 		{
5048 			.procname	= "router_solicitations",
5049 			.data		= &ipv6_devconf.rtr_solicits,
5050 			.maxlen		= sizeof(int),
5051 			.mode		= 0644,
5052 			.proc_handler	= proc_dointvec,
5053 		},
5054 		{
5055 			.procname	= "router_solicitation_interval",
5056 			.data		= &ipv6_devconf.rtr_solicit_interval,
5057 			.maxlen		= sizeof(int),
5058 			.mode		= 0644,
5059 			.proc_handler	= proc_dointvec_jiffies,
5060 		},
5061 		{
5062 			.procname	= "router_solicitation_delay",
5063 			.data		= &ipv6_devconf.rtr_solicit_delay,
5064 			.maxlen		= sizeof(int),
5065 			.mode		= 0644,
5066 			.proc_handler	= proc_dointvec_jiffies,
5067 		},
5068 		{
5069 			.procname	= "force_mld_version",
5070 			.data		= &ipv6_devconf.force_mld_version,
5071 			.maxlen		= sizeof(int),
5072 			.mode		= 0644,
5073 			.proc_handler	= proc_dointvec,
5074 		},
5075 		{
5076 			.procname	= "mldv1_unsolicited_report_interval",
5077 			.data		=
5078 				&ipv6_devconf.mldv1_unsolicited_report_interval,
5079 			.maxlen		= sizeof(int),
5080 			.mode		= 0644,
5081 			.proc_handler	= proc_dointvec_ms_jiffies,
5082 		},
5083 		{
5084 			.procname	= "mldv2_unsolicited_report_interval",
5085 			.data		=
5086 				&ipv6_devconf.mldv2_unsolicited_report_interval,
5087 			.maxlen		= sizeof(int),
5088 			.mode		= 0644,
5089 			.proc_handler	= proc_dointvec_ms_jiffies,
5090 		},
5091 		{
5092 			.procname	= "use_tempaddr",
5093 			.data		= &ipv6_devconf.use_tempaddr,
5094 			.maxlen		= sizeof(int),
5095 			.mode		= 0644,
5096 			.proc_handler	= proc_dointvec,
5097 		},
5098 		{
5099 			.procname	= "temp_valid_lft",
5100 			.data		= &ipv6_devconf.temp_valid_lft,
5101 			.maxlen		= sizeof(int),
5102 			.mode		= 0644,
5103 			.proc_handler	= proc_dointvec,
5104 		},
5105 		{
5106 			.procname	= "temp_prefered_lft",
5107 			.data		= &ipv6_devconf.temp_prefered_lft,
5108 			.maxlen		= sizeof(int),
5109 			.mode		= 0644,
5110 			.proc_handler	= proc_dointvec,
5111 		},
5112 		{
5113 			.procname	= "regen_max_retry",
5114 			.data		= &ipv6_devconf.regen_max_retry,
5115 			.maxlen		= sizeof(int),
5116 			.mode		= 0644,
5117 			.proc_handler	= proc_dointvec,
5118 		},
5119 		{
5120 			.procname	= "max_desync_factor",
5121 			.data		= &ipv6_devconf.max_desync_factor,
5122 			.maxlen		= sizeof(int),
5123 			.mode		= 0644,
5124 			.proc_handler	= proc_dointvec,
5125 		},
5126 		{
5127 			.procname	= "max_addresses",
5128 			.data		= &ipv6_devconf.max_addresses,
5129 			.maxlen		= sizeof(int),
5130 			.mode		= 0644,
5131 			.proc_handler	= proc_dointvec,
5132 		},
5133 		{
5134 			.procname	= "accept_ra_defrtr",
5135 			.data		= &ipv6_devconf.accept_ra_defrtr,
5136 			.maxlen		= sizeof(int),
5137 			.mode		= 0644,
5138 			.proc_handler	= proc_dointvec,
5139 		},
5140 		{
5141 			.procname	= "accept_ra_pinfo",
5142 			.data		= &ipv6_devconf.accept_ra_pinfo,
5143 			.maxlen		= sizeof(int),
5144 			.mode		= 0644,
5145 			.proc_handler	= proc_dointvec,
5146 		},
5147 #ifdef CONFIG_IPV6_ROUTER_PREF
5148 		{
5149 			.procname	= "accept_ra_rtr_pref",
5150 			.data		= &ipv6_devconf.accept_ra_rtr_pref,
5151 			.maxlen		= sizeof(int),
5152 			.mode		= 0644,
5153 			.proc_handler	= proc_dointvec,
5154 		},
5155 		{
5156 			.procname	= "router_probe_interval",
5157 			.data		= &ipv6_devconf.rtr_probe_interval,
5158 			.maxlen		= sizeof(int),
5159 			.mode		= 0644,
5160 			.proc_handler	= proc_dointvec_jiffies,
5161 		},
5162 #ifdef CONFIG_IPV6_ROUTE_INFO
5163 		{
5164 			.procname	= "accept_ra_rt_info_max_plen",
5165 			.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
5166 			.maxlen		= sizeof(int),
5167 			.mode		= 0644,
5168 			.proc_handler	= proc_dointvec,
5169 		},
5170 #endif
5171 #endif
5172 		{
5173 			.procname	= "proxy_ndp",
5174 			.data		= &ipv6_devconf.proxy_ndp,
5175 			.maxlen		= sizeof(int),
5176 			.mode		= 0644,
5177 			.proc_handler	= addrconf_sysctl_proxy_ndp,
5178 		},
5179 		{
5180 			.procname	= "accept_source_route",
5181 			.data		= &ipv6_devconf.accept_source_route,
5182 			.maxlen		= sizeof(int),
5183 			.mode		= 0644,
5184 			.proc_handler	= proc_dointvec,
5185 		},
5186 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5187 		{
5188 			.procname       = "optimistic_dad",
5189 			.data           = &ipv6_devconf.optimistic_dad,
5190 			.maxlen         = sizeof(int),
5191 			.mode           = 0644,
5192 			.proc_handler   = proc_dointvec,
5193 
5194 		},
5195 		{
5196 			.procname       = "use_optimistic",
5197 			.data           = &ipv6_devconf.use_optimistic,
5198 			.maxlen         = sizeof(int),
5199 			.mode           = 0644,
5200 			.proc_handler   = proc_dointvec,
5201 
5202 		},
5203 #endif
5204 #ifdef CONFIG_IPV6_MROUTE
5205 		{
5206 			.procname	= "mc_forwarding",
5207 			.data		= &ipv6_devconf.mc_forwarding,
5208 			.maxlen		= sizeof(int),
5209 			.mode		= 0444,
5210 			.proc_handler	= proc_dointvec,
5211 		},
5212 #endif
5213 		{
5214 			.procname	= "disable_ipv6",
5215 			.data		= &ipv6_devconf.disable_ipv6,
5216 			.maxlen		= sizeof(int),
5217 			.mode		= 0644,
5218 			.proc_handler	= addrconf_sysctl_disable,
5219 		},
5220 		{
5221 			.procname	= "accept_dad",
5222 			.data		= &ipv6_devconf.accept_dad,
5223 			.maxlen		= sizeof(int),
5224 			.mode		= 0644,
5225 			.proc_handler	= proc_dointvec,
5226 		},
5227 		{
5228 			.procname       = "force_tllao",
5229 			.data           = &ipv6_devconf.force_tllao,
5230 			.maxlen         = sizeof(int),
5231 			.mode           = 0644,
5232 			.proc_handler   = proc_dointvec
5233 		},
5234 		{
5235 			.procname       = "ndisc_notify",
5236 			.data           = &ipv6_devconf.ndisc_notify,
5237 			.maxlen         = sizeof(int),
5238 			.mode           = 0644,
5239 			.proc_handler   = proc_dointvec
5240 		},
5241 		{
5242 			.procname	= "suppress_frag_ndisc",
5243 			.data		= &ipv6_devconf.suppress_frag_ndisc,
5244 			.maxlen		= sizeof(int),
5245 			.mode		= 0644,
5246 			.proc_handler	= proc_dointvec
5247 		},
5248 		{
5249 			.procname	= "accept_ra_from_local",
5250 			.data		= &ipv6_devconf.accept_ra_from_local,
5251 			.maxlen		= sizeof(int),
5252 			.mode		= 0644,
5253 			.proc_handler	= proc_dointvec,
5254 		},
5255 		{
5256 			/* sentinel */
5257 		}
5258 	},
5259 };
5260 
5261 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
5262 		struct inet6_dev *idev, struct ipv6_devconf *p)
5263 {
5264 	int i;
5265 	struct addrconf_sysctl_table *t;
5266 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
5267 
5268 	t = kmemdup(&addrconf_sysctl, sizeof(*t), GFP_KERNEL);
5269 	if (t == NULL)
5270 		goto out;
5271 
5272 	for (i = 0; t->addrconf_vars[i].data; i++) {
5273 		t->addrconf_vars[i].data += (char *)p - (char *)&ipv6_devconf;
5274 		t->addrconf_vars[i].extra1 = idev; /* embedded; no ref */
5275 		t->addrconf_vars[i].extra2 = net;
5276 	}
5277 
5278 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
5279 
5280 	t->sysctl_header = register_net_sysctl(net, path, t->addrconf_vars);
5281 	if (t->sysctl_header == NULL)
5282 		goto free;
5283 
5284 	p->sysctl = t;
5285 	return 0;
5286 
5287 free:
5288 	kfree(t);
5289 out:
5290 	return -ENOBUFS;
5291 }
5292 
5293 static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
5294 {
5295 	struct addrconf_sysctl_table *t;
5296 
5297 	if (p->sysctl == NULL)
5298 		return;
5299 
5300 	t = p->sysctl;
5301 	p->sysctl = NULL;
5302 	unregister_net_sysctl_table(t->sysctl_header);
5303 	kfree(t);
5304 }
5305 
5306 static int addrconf_sysctl_register(struct inet6_dev *idev)
5307 {
5308 	int err;
5309 
5310 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
5311 		return -EINVAL;
5312 
5313 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
5314 				    &ndisc_ifinfo_sysctl_change);
5315 	if (err)
5316 		return err;
5317 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
5318 					 idev, &idev->cnf);
5319 	if (err)
5320 		neigh_sysctl_unregister(idev->nd_parms);
5321 
5322 	return err;
5323 }
5324 
5325 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
5326 {
5327 	__addrconf_sysctl_unregister(&idev->cnf);
5328 	neigh_sysctl_unregister(idev->nd_parms);
5329 }
5330 
5331 
5332 #endif
5333 
5334 static int __net_init addrconf_init_net(struct net *net)
5335 {
5336 	int err = -ENOMEM;
5337 	struct ipv6_devconf *all, *dflt;
5338 
5339 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
5340 	if (all == NULL)
5341 		goto err_alloc_all;
5342 
5343 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
5344 	if (dflt == NULL)
5345 		goto err_alloc_dflt;
5346 
5347 	/* these will be inherited by all namespaces */
5348 	dflt->autoconf = ipv6_defaults.autoconf;
5349 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
5350 
5351 	net->ipv6.devconf_all = all;
5352 	net->ipv6.devconf_dflt = dflt;
5353 
5354 #ifdef CONFIG_SYSCTL
5355 	err = __addrconf_sysctl_register(net, "all", NULL, all);
5356 	if (err < 0)
5357 		goto err_reg_all;
5358 
5359 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
5360 	if (err < 0)
5361 		goto err_reg_dflt;
5362 #endif
5363 	return 0;
5364 
5365 #ifdef CONFIG_SYSCTL
5366 err_reg_dflt:
5367 	__addrconf_sysctl_unregister(all);
5368 err_reg_all:
5369 	kfree(dflt);
5370 #endif
5371 err_alloc_dflt:
5372 	kfree(all);
5373 err_alloc_all:
5374 	return err;
5375 }
5376 
5377 static void __net_exit addrconf_exit_net(struct net *net)
5378 {
5379 #ifdef CONFIG_SYSCTL
5380 	__addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
5381 	__addrconf_sysctl_unregister(net->ipv6.devconf_all);
5382 #endif
5383 	kfree(net->ipv6.devconf_dflt);
5384 	kfree(net->ipv6.devconf_all);
5385 }
5386 
5387 static struct pernet_operations addrconf_ops = {
5388 	.init = addrconf_init_net,
5389 	.exit = addrconf_exit_net,
5390 };
5391 
5392 static struct rtnl_af_ops inet6_ops = {
5393 	.family		  = AF_INET6,
5394 	.fill_link_af	  = inet6_fill_link_af,
5395 	.get_link_af_size = inet6_get_link_af_size,
5396 	.set_link_af	  = inet6_set_link_af,
5397 };
5398 
5399 /*
5400  *	Init / cleanup code
5401  */
5402 
5403 int __init addrconf_init(void)
5404 {
5405 	struct inet6_dev *idev;
5406 	int i, err;
5407 
5408 	err = ipv6_addr_label_init();
5409 	if (err < 0) {
5410 		pr_crit("%s: cannot initialize default policy table: %d\n",
5411 			__func__, err);
5412 		goto out;
5413 	}
5414 
5415 	err = register_pernet_subsys(&addrconf_ops);
5416 	if (err < 0)
5417 		goto out_addrlabel;
5418 
5419 	addrconf_wq = create_workqueue("ipv6_addrconf");
5420 	if (!addrconf_wq) {
5421 		err = -ENOMEM;
5422 		goto out_nowq;
5423 	}
5424 
5425 	/* The addrconf netdev notifier requires that loopback_dev
5426 	 * has it's ipv6 private information allocated and setup
5427 	 * before it can bring up and give link-local addresses
5428 	 * to other devices which are up.
5429 	 *
5430 	 * Unfortunately, loopback_dev is not necessarily the first
5431 	 * entry in the global dev_base list of net devices.  In fact,
5432 	 * it is likely to be the very last entry on that list.
5433 	 * So this causes the notifier registry below to try and
5434 	 * give link-local addresses to all devices besides loopback_dev
5435 	 * first, then loopback_dev, which cases all the non-loopback_dev
5436 	 * devices to fail to get a link-local address.
5437 	 *
5438 	 * So, as a temporary fix, allocate the ipv6 structure for
5439 	 * loopback_dev first by hand.
5440 	 * Longer term, all of the dependencies ipv6 has upon the loopback
5441 	 * device and it being up should be removed.
5442 	 */
5443 	rtnl_lock();
5444 	idev = ipv6_add_dev(init_net.loopback_dev);
5445 	rtnl_unlock();
5446 	if (IS_ERR(idev)) {
5447 		err = PTR_ERR(idev);
5448 		goto errlo;
5449 	}
5450 
5451 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
5452 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
5453 
5454 	register_netdevice_notifier(&ipv6_dev_notf);
5455 
5456 	addrconf_verify();
5457 
5458 	rtnl_af_register(&inet6_ops);
5459 
5460 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
5461 			      NULL);
5462 	if (err < 0)
5463 		goto errout;
5464 
5465 	/* Only the first call to __rtnl_register can fail */
5466 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, NULL);
5467 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, NULL);
5468 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
5469 			inet6_dump_ifaddr, NULL);
5470 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
5471 			inet6_dump_ifmcaddr, NULL);
5472 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
5473 			inet6_dump_ifacaddr, NULL);
5474 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
5475 			inet6_netconf_dump_devconf, NULL);
5476 
5477 	ipv6_addr_label_rtnl_register();
5478 
5479 	return 0;
5480 errout:
5481 	rtnl_af_unregister(&inet6_ops);
5482 	unregister_netdevice_notifier(&ipv6_dev_notf);
5483 errlo:
5484 	destroy_workqueue(addrconf_wq);
5485 out_nowq:
5486 	unregister_pernet_subsys(&addrconf_ops);
5487 out_addrlabel:
5488 	ipv6_addr_label_cleanup();
5489 out:
5490 	return err;
5491 }
5492 
5493 void addrconf_cleanup(void)
5494 {
5495 	struct net_device *dev;
5496 	int i;
5497 
5498 	unregister_netdevice_notifier(&ipv6_dev_notf);
5499 	unregister_pernet_subsys(&addrconf_ops);
5500 	ipv6_addr_label_cleanup();
5501 
5502 	rtnl_lock();
5503 
5504 	__rtnl_af_unregister(&inet6_ops);
5505 
5506 	/* clean dev list */
5507 	for_each_netdev(&init_net, dev) {
5508 		if (__in6_dev_get(dev) == NULL)
5509 			continue;
5510 		addrconf_ifdown(dev, 1);
5511 	}
5512 	addrconf_ifdown(init_net.loopback_dev, 2);
5513 
5514 	/*
5515 	 *	Check hash table.
5516 	 */
5517 	spin_lock_bh(&addrconf_hash_lock);
5518 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
5519 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
5520 	spin_unlock_bh(&addrconf_hash_lock);
5521 	cancel_delayed_work(&addr_chk_work);
5522 	rtnl_unlock();
5523 
5524 	destroy_workqueue(addrconf_wq);
5525 }
5526