xref: /linux/net/ipv6/addrconf.c (revision 6f876ce4b53f7c748e07cedab661aa4bcc8a09d2)
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/inet.h>
50 #include <linux/in6.h>
51 #include <linux/netdevice.h>
52 #include <linux/if_addr.h>
53 #include <linux/if_arp.h>
54 #include <linux/if_arcnet.h>
55 #include <linux/if_infiniband.h>
56 #include <linux/route.h>
57 #include <linux/inetdevice.h>
58 #include <linux/init.h>
59 #include <linux/slab.h>
60 #ifdef CONFIG_SYSCTL
61 #include <linux/sysctl.h>
62 #endif
63 #include <linux/capability.h>
64 #include <linux/delay.h>
65 #include <linux/notifier.h>
66 #include <linux/string.h>
67 #include <linux/hash.h>
68 
69 #include <net/net_namespace.h>
70 #include <net/sock.h>
71 #include <net/snmp.h>
72 
73 #include <net/af_ieee802154.h>
74 #include <net/firewire.h>
75 #include <net/ipv6.h>
76 #include <net/protocol.h>
77 #include <net/ndisc.h>
78 #include <net/ip6_route.h>
79 #include <net/addrconf.h>
80 #include <net/tcp.h>
81 #include <net/ip.h>
82 #include <net/netlink.h>
83 #include <net/pkt_sched.h>
84 #include <linux/if_tunnel.h>
85 #include <linux/rtnetlink.h>
86 #include <linux/netconf.h>
87 #include <linux/random.h>
88 #include <linux/uaccess.h>
89 #include <asm/unaligned.h>
90 
91 #include <linux/proc_fs.h>
92 #include <linux/seq_file.h>
93 #include <linux/export.h>
94 
95 /* Set to 3 to get tracing... */
96 #define ACONF_DEBUG 2
97 
98 #if ACONF_DEBUG >= 3
99 #define ADBG(fmt, ...) printk(fmt, ##__VA_ARGS__)
100 #else
101 #define ADBG(fmt, ...) do { if (0) printk(fmt, ##__VA_ARGS__); } while (0)
102 #endif
103 
104 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
105 
106 #define IPV6_MAX_STRLEN \
107 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
108 
109 static inline u32 cstamp_delta(unsigned long cstamp)
110 {
111 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
112 }
113 
114 #ifdef CONFIG_SYSCTL
115 static int addrconf_sysctl_register(struct inet6_dev *idev);
116 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
117 #else
118 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
119 {
120 	return 0;
121 }
122 
123 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
124 {
125 }
126 #endif
127 
128 static void __ipv6_regen_rndid(struct inet6_dev *idev);
129 static void __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
130 static void ipv6_regen_rndid(unsigned long data);
131 
132 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
133 static int ipv6_count_addresses(struct inet6_dev *idev);
134 static int ipv6_generate_stable_address(struct in6_addr *addr,
135 					u8 dad_count,
136 					const struct inet6_dev *idev);
137 
138 /*
139  *	Configured unicast address hash table
140  */
141 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
142 static DEFINE_SPINLOCK(addrconf_hash_lock);
143 
144 static void addrconf_verify(void);
145 static void addrconf_verify_rtnl(void);
146 static void addrconf_verify_work(struct work_struct *);
147 
148 static struct workqueue_struct *addrconf_wq;
149 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
150 
151 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
152 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
153 
154 static void addrconf_type_change(struct net_device *dev,
155 				 unsigned long event);
156 static int addrconf_ifdown(struct net_device *dev, int how);
157 
158 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
159 						  int plen,
160 						  const struct net_device *dev,
161 						  u32 flags, u32 noflags);
162 
163 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
164 static void addrconf_dad_work(struct work_struct *w);
165 static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
166 static void addrconf_dad_run(struct inet6_dev *idev);
167 static void addrconf_rs_timer(unsigned long data);
168 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
169 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
170 
171 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
172 				struct prefix_info *pinfo);
173 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
174 			       struct net_device *dev);
175 
176 static struct ipv6_devconf ipv6_devconf __read_mostly = {
177 	.forwarding		= 0,
178 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
179 	.mtu6			= IPV6_MIN_MTU,
180 	.accept_ra		= 1,
181 	.accept_redirects	= 1,
182 	.autoconf		= 1,
183 	.force_mld_version	= 0,
184 	.mldv1_unsolicited_report_interval = 10 * HZ,
185 	.mldv2_unsolicited_report_interval = HZ,
186 	.dad_transmits		= 1,
187 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
188 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
189 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
190 	.use_tempaddr		= 0,
191 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
192 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
193 	.regen_max_retry	= REGEN_MAX_RETRY,
194 	.max_desync_factor	= MAX_DESYNC_FACTOR,
195 	.max_addresses		= IPV6_MAX_ADDRESSES,
196 	.accept_ra_defrtr	= 1,
197 	.accept_ra_from_local	= 0,
198 	.accept_ra_pinfo	= 1,
199 #ifdef CONFIG_IPV6_ROUTER_PREF
200 	.accept_ra_rtr_pref	= 1,
201 	.rtr_probe_interval	= 60 * HZ,
202 #ifdef CONFIG_IPV6_ROUTE_INFO
203 	.accept_ra_rt_info_max_plen = 0,
204 #endif
205 #endif
206 	.proxy_ndp		= 0,
207 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
208 	.disable_ipv6		= 0,
209 	.accept_dad		= 1,
210 	.suppress_frag_ndisc	= 1,
211 	.accept_ra_mtu		= 1,
212 	.stable_secret		= {
213 		.initialized = false,
214 	}
215 };
216 
217 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
218 	.forwarding		= 0,
219 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
220 	.mtu6			= IPV6_MIN_MTU,
221 	.accept_ra		= 1,
222 	.accept_redirects	= 1,
223 	.autoconf		= 1,
224 	.force_mld_version	= 0,
225 	.mldv1_unsolicited_report_interval = 10 * HZ,
226 	.mldv2_unsolicited_report_interval = HZ,
227 	.dad_transmits		= 1,
228 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
229 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
230 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
231 	.use_tempaddr		= 0,
232 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
233 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
234 	.regen_max_retry	= REGEN_MAX_RETRY,
235 	.max_desync_factor	= MAX_DESYNC_FACTOR,
236 	.max_addresses		= IPV6_MAX_ADDRESSES,
237 	.accept_ra_defrtr	= 1,
238 	.accept_ra_from_local	= 0,
239 	.accept_ra_pinfo	= 1,
240 #ifdef CONFIG_IPV6_ROUTER_PREF
241 	.accept_ra_rtr_pref	= 1,
242 	.rtr_probe_interval	= 60 * HZ,
243 #ifdef CONFIG_IPV6_ROUTE_INFO
244 	.accept_ra_rt_info_max_plen = 0,
245 #endif
246 #endif
247 	.proxy_ndp		= 0,
248 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
249 	.disable_ipv6		= 0,
250 	.accept_dad		= 1,
251 	.suppress_frag_ndisc	= 1,
252 	.accept_ra_mtu		= 1,
253 	.stable_secret		= {
254 		.initialized = false,
255 	},
256 };
257 
258 /* Check if a valid qdisc is available */
259 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
260 {
261 	return !qdisc_tx_is_noop(dev);
262 }
263 
264 static void addrconf_del_rs_timer(struct inet6_dev *idev)
265 {
266 	if (del_timer(&idev->rs_timer))
267 		__in6_dev_put(idev);
268 }
269 
270 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
271 {
272 	if (cancel_delayed_work(&ifp->dad_work))
273 		__in6_ifa_put(ifp);
274 }
275 
276 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
277 				  unsigned long when)
278 {
279 	if (!timer_pending(&idev->rs_timer))
280 		in6_dev_hold(idev);
281 	mod_timer(&idev->rs_timer, jiffies + when);
282 }
283 
284 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
285 				   unsigned long delay)
286 {
287 	if (!delayed_work_pending(&ifp->dad_work))
288 		in6_ifa_hold(ifp);
289 	mod_delayed_work(addrconf_wq, &ifp->dad_work, delay);
290 }
291 
292 static int snmp6_alloc_dev(struct inet6_dev *idev)
293 {
294 	int i;
295 
296 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
297 	if (!idev->stats.ipv6)
298 		goto err_ip;
299 
300 	for_each_possible_cpu(i) {
301 		struct ipstats_mib *addrconf_stats;
302 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
303 		u64_stats_init(&addrconf_stats->syncp);
304 	}
305 
306 
307 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
308 					GFP_KERNEL);
309 	if (!idev->stats.icmpv6dev)
310 		goto err_icmp;
311 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
312 					   GFP_KERNEL);
313 	if (!idev->stats.icmpv6msgdev)
314 		goto err_icmpmsg;
315 
316 	return 0;
317 
318 err_icmpmsg:
319 	kfree(idev->stats.icmpv6dev);
320 err_icmp:
321 	free_percpu(idev->stats.ipv6);
322 err_ip:
323 	return -ENOMEM;
324 }
325 
326 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
327 {
328 	struct inet6_dev *ndev;
329 	int err = -ENOMEM;
330 
331 	ASSERT_RTNL();
332 
333 	if (dev->mtu < IPV6_MIN_MTU)
334 		return ERR_PTR(-EINVAL);
335 
336 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
337 	if (!ndev)
338 		return ERR_PTR(err);
339 
340 	rwlock_init(&ndev->lock);
341 	ndev->dev = dev;
342 	INIT_LIST_HEAD(&ndev->addr_list);
343 	setup_timer(&ndev->rs_timer, addrconf_rs_timer,
344 		    (unsigned long)ndev);
345 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
346 	ndev->cnf.mtu6 = dev->mtu;
347 	ndev->cnf.sysctl = NULL;
348 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
349 	if (!ndev->nd_parms) {
350 		kfree(ndev);
351 		return ERR_PTR(err);
352 	}
353 	if (ndev->cnf.forwarding)
354 		dev_disable_lro(dev);
355 	/* We refer to the device */
356 	dev_hold(dev);
357 
358 	if (snmp6_alloc_dev(ndev) < 0) {
359 		ADBG(KERN_WARNING
360 			"%s: cannot allocate memory for statistics; dev=%s.\n",
361 			__func__, dev->name);
362 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
363 		dev_put(dev);
364 		kfree(ndev);
365 		return ERR_PTR(err);
366 	}
367 
368 	if (snmp6_register_dev(ndev) < 0) {
369 		ADBG(KERN_WARNING
370 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
371 			__func__, dev->name);
372 		goto err_release;
373 	}
374 
375 	/* One reference from device.  We must do this before
376 	 * we invoke __ipv6_regen_rndid().
377 	 */
378 	in6_dev_hold(ndev);
379 
380 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
381 		ndev->cnf.accept_dad = -1;
382 
383 #if IS_ENABLED(CONFIG_IPV6_SIT)
384 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
385 		pr_info("%s: Disabled Multicast RS\n", dev->name);
386 		ndev->cnf.rtr_solicits = 0;
387 	}
388 #endif
389 
390 	INIT_LIST_HEAD(&ndev->tempaddr_list);
391 	setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
392 	if ((dev->flags&IFF_LOOPBACK) ||
393 	    dev->type == ARPHRD_TUNNEL ||
394 	    dev->type == ARPHRD_TUNNEL6 ||
395 	    dev->type == ARPHRD_SIT ||
396 	    dev->type == ARPHRD_NONE) {
397 		ndev->cnf.use_tempaddr = -1;
398 	} else {
399 		in6_dev_hold(ndev);
400 		ipv6_regen_rndid((unsigned long) ndev);
401 	}
402 
403 	ndev->token = in6addr_any;
404 
405 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
406 		ndev->if_flags |= IF_READY;
407 
408 	ipv6_mc_init_dev(ndev);
409 	ndev->tstamp = jiffies;
410 	err = addrconf_sysctl_register(ndev);
411 	if (err) {
412 		ipv6_mc_destroy_dev(ndev);
413 		del_timer(&ndev->regen_timer);
414 		goto err_release;
415 	}
416 	/* protected by rtnl_lock */
417 	rcu_assign_pointer(dev->ip6_ptr, ndev);
418 
419 	/* Join interface-local all-node multicast group */
420 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
421 
422 	/* Join all-node multicast group */
423 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
424 
425 	/* Join all-router multicast group if forwarding is set */
426 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
427 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
428 
429 	return ndev;
430 
431 err_release:
432 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
433 	ndev->dead = 1;
434 	in6_dev_finish_destroy(ndev);
435 	return ERR_PTR(err);
436 }
437 
438 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
439 {
440 	struct inet6_dev *idev;
441 
442 	ASSERT_RTNL();
443 
444 	idev = __in6_dev_get(dev);
445 	if (!idev) {
446 		idev = ipv6_add_dev(dev);
447 		if (IS_ERR(idev))
448 			return NULL;
449 	}
450 
451 	if (dev->flags&IFF_UP)
452 		ipv6_mc_up(idev);
453 	return idev;
454 }
455 
456 static int inet6_netconf_msgsize_devconf(int type)
457 {
458 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
459 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
460 
461 	/* type -1 is used for ALL */
462 	if (type == -1 || type == NETCONFA_FORWARDING)
463 		size += nla_total_size(4);
464 #ifdef CONFIG_IPV6_MROUTE
465 	if (type == -1 || type == NETCONFA_MC_FORWARDING)
466 		size += nla_total_size(4);
467 #endif
468 	if (type == -1 || type == NETCONFA_PROXY_NEIGH)
469 		size += nla_total_size(4);
470 
471 	return size;
472 }
473 
474 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
475 				      struct ipv6_devconf *devconf, u32 portid,
476 				      u32 seq, int event, unsigned int flags,
477 				      int type)
478 {
479 	struct nlmsghdr  *nlh;
480 	struct netconfmsg *ncm;
481 
482 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
483 			flags);
484 	if (!nlh)
485 		return -EMSGSIZE;
486 
487 	ncm = nlmsg_data(nlh);
488 	ncm->ncm_family = AF_INET6;
489 
490 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
491 		goto nla_put_failure;
492 
493 	/* type -1 is used for ALL */
494 	if ((type == -1 || type == NETCONFA_FORWARDING) &&
495 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
496 		goto nla_put_failure;
497 #ifdef CONFIG_IPV6_MROUTE
498 	if ((type == -1 || type == NETCONFA_MC_FORWARDING) &&
499 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
500 			devconf->mc_forwarding) < 0)
501 		goto nla_put_failure;
502 #endif
503 	if ((type == -1 || type == NETCONFA_PROXY_NEIGH) &&
504 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
505 		goto nla_put_failure;
506 
507 	nlmsg_end(skb, nlh);
508 	return 0;
509 
510 nla_put_failure:
511 	nlmsg_cancel(skb, nlh);
512 	return -EMSGSIZE;
513 }
514 
515 void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
516 				  struct ipv6_devconf *devconf)
517 {
518 	struct sk_buff *skb;
519 	int err = -ENOBUFS;
520 
521 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_ATOMIC);
522 	if (!skb)
523 		goto errout;
524 
525 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
526 					 RTM_NEWNETCONF, 0, type);
527 	if (err < 0) {
528 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
529 		WARN_ON(err == -EMSGSIZE);
530 		kfree_skb(skb);
531 		goto errout;
532 	}
533 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_ATOMIC);
534 	return;
535 errout:
536 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
537 }
538 
539 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
540 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
541 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
542 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
543 };
544 
545 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
546 				     struct nlmsghdr *nlh)
547 {
548 	struct net *net = sock_net(in_skb->sk);
549 	struct nlattr *tb[NETCONFA_MAX+1];
550 	struct netconfmsg *ncm;
551 	struct sk_buff *skb;
552 	struct ipv6_devconf *devconf;
553 	struct inet6_dev *in6_dev;
554 	struct net_device *dev;
555 	int ifindex;
556 	int err;
557 
558 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
559 			  devconf_ipv6_policy);
560 	if (err < 0)
561 		goto errout;
562 
563 	err = EINVAL;
564 	if (!tb[NETCONFA_IFINDEX])
565 		goto errout;
566 
567 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
568 	switch (ifindex) {
569 	case NETCONFA_IFINDEX_ALL:
570 		devconf = net->ipv6.devconf_all;
571 		break;
572 	case NETCONFA_IFINDEX_DEFAULT:
573 		devconf = net->ipv6.devconf_dflt;
574 		break;
575 	default:
576 		dev = __dev_get_by_index(net, ifindex);
577 		if (!dev)
578 			goto errout;
579 		in6_dev = __in6_dev_get(dev);
580 		if (!in6_dev)
581 			goto errout;
582 		devconf = &in6_dev->cnf;
583 		break;
584 	}
585 
586 	err = -ENOBUFS;
587 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(-1), GFP_ATOMIC);
588 	if (!skb)
589 		goto errout;
590 
591 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
592 					 NETLINK_CB(in_skb).portid,
593 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
594 					 -1);
595 	if (err < 0) {
596 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
597 		WARN_ON(err == -EMSGSIZE);
598 		kfree_skb(skb);
599 		goto errout;
600 	}
601 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
602 errout:
603 	return err;
604 }
605 
606 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
607 				      struct netlink_callback *cb)
608 {
609 	struct net *net = sock_net(skb->sk);
610 	int h, s_h;
611 	int idx, s_idx;
612 	struct net_device *dev;
613 	struct inet6_dev *idev;
614 	struct hlist_head *head;
615 
616 	s_h = cb->args[0];
617 	s_idx = idx = cb->args[1];
618 
619 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
620 		idx = 0;
621 		head = &net->dev_index_head[h];
622 		rcu_read_lock();
623 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
624 			  net->dev_base_seq;
625 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
626 			if (idx < s_idx)
627 				goto cont;
628 			idev = __in6_dev_get(dev);
629 			if (!idev)
630 				goto cont;
631 
632 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
633 						       &idev->cnf,
634 						       NETLINK_CB(cb->skb).portid,
635 						       cb->nlh->nlmsg_seq,
636 						       RTM_NEWNETCONF,
637 						       NLM_F_MULTI,
638 						       -1) < 0) {
639 				rcu_read_unlock();
640 				goto done;
641 			}
642 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
643 cont:
644 			idx++;
645 		}
646 		rcu_read_unlock();
647 	}
648 	if (h == NETDEV_HASHENTRIES) {
649 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
650 					       net->ipv6.devconf_all,
651 					       NETLINK_CB(cb->skb).portid,
652 					       cb->nlh->nlmsg_seq,
653 					       RTM_NEWNETCONF, NLM_F_MULTI,
654 					       -1) < 0)
655 			goto done;
656 		else
657 			h++;
658 	}
659 	if (h == NETDEV_HASHENTRIES + 1) {
660 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
661 					       net->ipv6.devconf_dflt,
662 					       NETLINK_CB(cb->skb).portid,
663 					       cb->nlh->nlmsg_seq,
664 					       RTM_NEWNETCONF, NLM_F_MULTI,
665 					       -1) < 0)
666 			goto done;
667 		else
668 			h++;
669 	}
670 done:
671 	cb->args[0] = h;
672 	cb->args[1] = idx;
673 
674 	return skb->len;
675 }
676 
677 #ifdef CONFIG_SYSCTL
678 static void dev_forward_change(struct inet6_dev *idev)
679 {
680 	struct net_device *dev;
681 	struct inet6_ifaddr *ifa;
682 
683 	if (!idev)
684 		return;
685 	dev = idev->dev;
686 	if (idev->cnf.forwarding)
687 		dev_disable_lro(dev);
688 	if (dev->flags & IFF_MULTICAST) {
689 		if (idev->cnf.forwarding) {
690 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
691 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
692 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
693 		} else {
694 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
695 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
696 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
697 		}
698 	}
699 
700 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
701 		if (ifa->flags&IFA_F_TENTATIVE)
702 			continue;
703 		if (idev->cnf.forwarding)
704 			addrconf_join_anycast(ifa);
705 		else
706 			addrconf_leave_anycast(ifa);
707 	}
708 	inet6_netconf_notify_devconf(dev_net(dev), NETCONFA_FORWARDING,
709 				     dev->ifindex, &idev->cnf);
710 }
711 
712 
713 static void addrconf_forward_change(struct net *net, __s32 newf)
714 {
715 	struct net_device *dev;
716 	struct inet6_dev *idev;
717 
718 	for_each_netdev(net, dev) {
719 		idev = __in6_dev_get(dev);
720 		if (idev) {
721 			int changed = (!idev->cnf.forwarding) ^ (!newf);
722 			idev->cnf.forwarding = newf;
723 			if (changed)
724 				dev_forward_change(idev);
725 		}
726 	}
727 }
728 
729 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
730 {
731 	struct net *net;
732 	int old;
733 
734 	if (!rtnl_trylock())
735 		return restart_syscall();
736 
737 	net = (struct net *)table->extra2;
738 	old = *p;
739 	*p = newf;
740 
741 	if (p == &net->ipv6.devconf_dflt->forwarding) {
742 		if ((!newf) ^ (!old))
743 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
744 						     NETCONFA_IFINDEX_DEFAULT,
745 						     net->ipv6.devconf_dflt);
746 		rtnl_unlock();
747 		return 0;
748 	}
749 
750 	if (p == &net->ipv6.devconf_all->forwarding) {
751 		net->ipv6.devconf_dflt->forwarding = newf;
752 		addrconf_forward_change(net, newf);
753 		if ((!newf) ^ (!old))
754 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
755 						     NETCONFA_IFINDEX_ALL,
756 						     net->ipv6.devconf_all);
757 	} else if ((!newf) ^ (!old))
758 		dev_forward_change((struct inet6_dev *)table->extra1);
759 	rtnl_unlock();
760 
761 	if (newf)
762 		rt6_purge_dflt_routers(net);
763 	return 1;
764 }
765 #endif
766 
767 /* Nobody refers to this ifaddr, destroy it */
768 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
769 {
770 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
771 
772 #ifdef NET_REFCNT_DEBUG
773 	pr_debug("%s\n", __func__);
774 #endif
775 
776 	in6_dev_put(ifp->idev);
777 
778 	if (cancel_delayed_work(&ifp->dad_work))
779 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
780 			  ifp);
781 
782 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
783 		pr_warn("Freeing alive inet6 address %p\n", ifp);
784 		return;
785 	}
786 	ip6_rt_put(ifp->rt);
787 
788 	kfree_rcu(ifp, rcu);
789 }
790 
791 static void
792 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
793 {
794 	struct list_head *p;
795 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
796 
797 	/*
798 	 * Each device address list is sorted in order of scope -
799 	 * global before linklocal.
800 	 */
801 	list_for_each(p, &idev->addr_list) {
802 		struct inet6_ifaddr *ifa
803 			= list_entry(p, struct inet6_ifaddr, if_list);
804 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
805 			break;
806 	}
807 
808 	list_add_tail(&ifp->if_list, p);
809 }
810 
811 static u32 inet6_addr_hash(const struct in6_addr *addr)
812 {
813 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
814 }
815 
816 /* On success it returns ifp with increased reference count */
817 
818 static struct inet6_ifaddr *
819 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
820 	      const struct in6_addr *peer_addr, int pfxlen,
821 	      int scope, u32 flags, u32 valid_lft, u32 prefered_lft)
822 {
823 	struct inet6_ifaddr *ifa = NULL;
824 	struct rt6_info *rt;
825 	unsigned int hash;
826 	int err = 0;
827 	int addr_type = ipv6_addr_type(addr);
828 
829 	if (addr_type == IPV6_ADDR_ANY ||
830 	    addr_type & IPV6_ADDR_MULTICAST ||
831 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
832 	     addr_type & IPV6_ADDR_LOOPBACK))
833 		return ERR_PTR(-EADDRNOTAVAIL);
834 
835 	rcu_read_lock_bh();
836 	if (idev->dead) {
837 		err = -ENODEV;			/*XXX*/
838 		goto out2;
839 	}
840 
841 	if (idev->cnf.disable_ipv6) {
842 		err = -EACCES;
843 		goto out2;
844 	}
845 
846 	spin_lock(&addrconf_hash_lock);
847 
848 	/* Ignore adding duplicate addresses on an interface */
849 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
850 		ADBG("ipv6_add_addr: already assigned\n");
851 		err = -EEXIST;
852 		goto out;
853 	}
854 
855 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
856 
857 	if (!ifa) {
858 		ADBG("ipv6_add_addr: malloc failed\n");
859 		err = -ENOBUFS;
860 		goto out;
861 	}
862 
863 	rt = addrconf_dst_alloc(idev, addr, false);
864 	if (IS_ERR(rt)) {
865 		err = PTR_ERR(rt);
866 		goto out;
867 	}
868 
869 	neigh_parms_data_state_setall(idev->nd_parms);
870 
871 	ifa->addr = *addr;
872 	if (peer_addr)
873 		ifa->peer_addr = *peer_addr;
874 
875 	spin_lock_init(&ifa->lock);
876 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
877 	INIT_HLIST_NODE(&ifa->addr_lst);
878 	ifa->scope = scope;
879 	ifa->prefix_len = pfxlen;
880 	ifa->flags = flags | IFA_F_TENTATIVE;
881 	ifa->valid_lft = valid_lft;
882 	ifa->prefered_lft = prefered_lft;
883 	ifa->cstamp = ifa->tstamp = jiffies;
884 	ifa->tokenized = false;
885 
886 	ifa->rt = rt;
887 
888 	ifa->idev = idev;
889 	in6_dev_hold(idev);
890 	/* For caller */
891 	in6_ifa_hold(ifa);
892 
893 	/* Add to big hash table */
894 	hash = inet6_addr_hash(addr);
895 
896 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
897 	spin_unlock(&addrconf_hash_lock);
898 
899 	write_lock(&idev->lock);
900 	/* Add to inet6_dev unicast addr list. */
901 	ipv6_link_dev_addr(idev, ifa);
902 
903 	if (ifa->flags&IFA_F_TEMPORARY) {
904 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
905 		in6_ifa_hold(ifa);
906 	}
907 
908 	in6_ifa_hold(ifa);
909 	write_unlock(&idev->lock);
910 out2:
911 	rcu_read_unlock_bh();
912 
913 	if (likely(err == 0))
914 		inet6addr_notifier_call_chain(NETDEV_UP, ifa);
915 	else {
916 		kfree(ifa);
917 		ifa = ERR_PTR(err);
918 	}
919 
920 	return ifa;
921 out:
922 	spin_unlock(&addrconf_hash_lock);
923 	goto out2;
924 }
925 
926 enum cleanup_prefix_rt_t {
927 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
928 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
929 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
930 };
931 
932 /*
933  * Check, whether the prefix for ifp would still need a prefix route
934  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
935  * constants.
936  *
937  * 1) we don't purge prefix if address was not permanent.
938  *    prefix is managed by its own lifetime.
939  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
940  * 3) if there are no addresses, delete prefix.
941  * 4) if there are still other permanent address(es),
942  *    corresponding prefix is still permanent.
943  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
944  *    don't purge the prefix, assume user space is managing it.
945  * 6) otherwise, update prefix lifetime to the
946  *    longest valid lifetime among the corresponding
947  *    addresses on the device.
948  *    Note: subsequent RA will update lifetime.
949  **/
950 static enum cleanup_prefix_rt_t
951 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
952 {
953 	struct inet6_ifaddr *ifa;
954 	struct inet6_dev *idev = ifp->idev;
955 	unsigned long lifetime;
956 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
957 
958 	*expires = jiffies;
959 
960 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
961 		if (ifa == ifp)
962 			continue;
963 		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
964 				       ifp->prefix_len))
965 			continue;
966 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
967 			return CLEANUP_PREFIX_RT_NOP;
968 
969 		action = CLEANUP_PREFIX_RT_EXPIRE;
970 
971 		spin_lock(&ifa->lock);
972 
973 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
974 		/*
975 		 * Note: Because this address is
976 		 * not permanent, lifetime <
977 		 * LONG_MAX / HZ here.
978 		 */
979 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
980 			*expires = ifa->tstamp + lifetime * HZ;
981 		spin_unlock(&ifa->lock);
982 	}
983 
984 	return action;
985 }
986 
987 static void
988 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
989 {
990 	struct rt6_info *rt;
991 
992 	rt = addrconf_get_prefix_route(&ifp->addr,
993 				       ifp->prefix_len,
994 				       ifp->idev->dev,
995 				       0, RTF_GATEWAY | RTF_DEFAULT);
996 	if (rt) {
997 		if (del_rt)
998 			ip6_del_rt(rt);
999 		else {
1000 			if (!(rt->rt6i_flags & RTF_EXPIRES))
1001 				rt6_set_expires(rt, expires);
1002 			ip6_rt_put(rt);
1003 		}
1004 	}
1005 }
1006 
1007 
1008 /* This function wants to get referenced ifp and releases it before return */
1009 
1010 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1011 {
1012 	int state;
1013 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1014 	unsigned long expires;
1015 
1016 	ASSERT_RTNL();
1017 
1018 	spin_lock_bh(&ifp->lock);
1019 	state = ifp->state;
1020 	ifp->state = INET6_IFADDR_STATE_DEAD;
1021 	spin_unlock_bh(&ifp->lock);
1022 
1023 	if (state == INET6_IFADDR_STATE_DEAD)
1024 		goto out;
1025 
1026 	spin_lock_bh(&addrconf_hash_lock);
1027 	hlist_del_init_rcu(&ifp->addr_lst);
1028 	spin_unlock_bh(&addrconf_hash_lock);
1029 
1030 	write_lock_bh(&ifp->idev->lock);
1031 
1032 	if (ifp->flags&IFA_F_TEMPORARY) {
1033 		list_del(&ifp->tmp_list);
1034 		if (ifp->ifpub) {
1035 			in6_ifa_put(ifp->ifpub);
1036 			ifp->ifpub = NULL;
1037 		}
1038 		__in6_ifa_put(ifp);
1039 	}
1040 
1041 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1042 		action = check_cleanup_prefix_route(ifp, &expires);
1043 
1044 	list_del_init(&ifp->if_list);
1045 	__in6_ifa_put(ifp);
1046 
1047 	write_unlock_bh(&ifp->idev->lock);
1048 
1049 	addrconf_del_dad_work(ifp);
1050 
1051 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1052 
1053 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1054 
1055 	if (action != CLEANUP_PREFIX_RT_NOP) {
1056 		cleanup_prefix_route(ifp, expires,
1057 			action == CLEANUP_PREFIX_RT_DEL);
1058 	}
1059 
1060 	/* clean up prefsrc entries */
1061 	rt6_remove_prefsrc(ifp);
1062 out:
1063 	in6_ifa_put(ifp);
1064 }
1065 
1066 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
1067 {
1068 	struct inet6_dev *idev = ifp->idev;
1069 	struct in6_addr addr, *tmpaddr;
1070 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
1071 	unsigned long regen_advance;
1072 	int tmp_plen;
1073 	int ret = 0;
1074 	u32 addr_flags;
1075 	unsigned long now = jiffies;
1076 
1077 	write_lock_bh(&idev->lock);
1078 	if (ift) {
1079 		spin_lock_bh(&ift->lock);
1080 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1081 		spin_unlock_bh(&ift->lock);
1082 		tmpaddr = &addr;
1083 	} else {
1084 		tmpaddr = NULL;
1085 	}
1086 retry:
1087 	in6_dev_hold(idev);
1088 	if (idev->cnf.use_tempaddr <= 0) {
1089 		write_unlock_bh(&idev->lock);
1090 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1091 		in6_dev_put(idev);
1092 		ret = -1;
1093 		goto out;
1094 	}
1095 	spin_lock_bh(&ifp->lock);
1096 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1097 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1098 		spin_unlock_bh(&ifp->lock);
1099 		write_unlock_bh(&idev->lock);
1100 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1101 			__func__);
1102 		in6_dev_put(idev);
1103 		ret = -1;
1104 		goto out;
1105 	}
1106 	in6_ifa_hold(ifp);
1107 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1108 	__ipv6_try_regen_rndid(idev, tmpaddr);
1109 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1110 	age = (now - ifp->tstamp) / HZ;
1111 	tmp_valid_lft = min_t(__u32,
1112 			      ifp->valid_lft,
1113 			      idev->cnf.temp_valid_lft + age);
1114 	tmp_prefered_lft = min_t(__u32,
1115 				 ifp->prefered_lft,
1116 				 idev->cnf.temp_prefered_lft + age -
1117 				 idev->cnf.max_desync_factor);
1118 	tmp_plen = ifp->prefix_len;
1119 	tmp_tstamp = ifp->tstamp;
1120 	spin_unlock_bh(&ifp->lock);
1121 
1122 	regen_advance = idev->cnf.regen_max_retry *
1123 			idev->cnf.dad_transmits *
1124 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1125 	write_unlock_bh(&idev->lock);
1126 
1127 	/* A temporary address is created only if this calculated Preferred
1128 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1129 	 * an implementation must not create a temporary address with a zero
1130 	 * Preferred Lifetime.
1131 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1132 	 * temporary addresses being generated.
1133 	 */
1134 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1135 	if (tmp_prefered_lft <= regen_advance + age) {
1136 		in6_ifa_put(ifp);
1137 		in6_dev_put(idev);
1138 		ret = -1;
1139 		goto out;
1140 	}
1141 
1142 	addr_flags = IFA_F_TEMPORARY;
1143 	/* set in addrconf_prefix_rcv() */
1144 	if (ifp->flags & IFA_F_OPTIMISTIC)
1145 		addr_flags |= IFA_F_OPTIMISTIC;
1146 
1147 	ift = ipv6_add_addr(idev, &addr, NULL, tmp_plen,
1148 			    ipv6_addr_scope(&addr), addr_flags,
1149 			    tmp_valid_lft, tmp_prefered_lft);
1150 	if (IS_ERR(ift)) {
1151 		in6_ifa_put(ifp);
1152 		in6_dev_put(idev);
1153 		pr_info("%s: retry temporary address regeneration\n", __func__);
1154 		tmpaddr = &addr;
1155 		write_lock_bh(&idev->lock);
1156 		goto retry;
1157 	}
1158 
1159 	spin_lock_bh(&ift->lock);
1160 	ift->ifpub = ifp;
1161 	ift->cstamp = now;
1162 	ift->tstamp = tmp_tstamp;
1163 	spin_unlock_bh(&ift->lock);
1164 
1165 	addrconf_dad_start(ift);
1166 	in6_ifa_put(ift);
1167 	in6_dev_put(idev);
1168 out:
1169 	return ret;
1170 }
1171 
1172 /*
1173  *	Choose an appropriate source address (RFC3484)
1174  */
1175 enum {
1176 	IPV6_SADDR_RULE_INIT = 0,
1177 	IPV6_SADDR_RULE_LOCAL,
1178 	IPV6_SADDR_RULE_SCOPE,
1179 	IPV6_SADDR_RULE_PREFERRED,
1180 #ifdef CONFIG_IPV6_MIP6
1181 	IPV6_SADDR_RULE_HOA,
1182 #endif
1183 	IPV6_SADDR_RULE_OIF,
1184 	IPV6_SADDR_RULE_LABEL,
1185 	IPV6_SADDR_RULE_PRIVACY,
1186 	IPV6_SADDR_RULE_ORCHID,
1187 	IPV6_SADDR_RULE_PREFIX,
1188 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1189 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1190 #endif
1191 	IPV6_SADDR_RULE_MAX
1192 };
1193 
1194 struct ipv6_saddr_score {
1195 	int			rule;
1196 	int			addr_type;
1197 	struct inet6_ifaddr	*ifa;
1198 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1199 	int			scopedist;
1200 	int			matchlen;
1201 };
1202 
1203 struct ipv6_saddr_dst {
1204 	const struct in6_addr *addr;
1205 	int ifindex;
1206 	int scope;
1207 	int label;
1208 	unsigned int prefs;
1209 };
1210 
1211 static inline int ipv6_saddr_preferred(int type)
1212 {
1213 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1214 		return 1;
1215 	return 0;
1216 }
1217 
1218 static inline bool ipv6_use_optimistic_addr(struct inet6_dev *idev)
1219 {
1220 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1221 	return idev && idev->cnf.optimistic_dad && idev->cnf.use_optimistic;
1222 #else
1223 	return false;
1224 #endif
1225 }
1226 
1227 static int ipv6_get_saddr_eval(struct net *net,
1228 			       struct ipv6_saddr_score *score,
1229 			       struct ipv6_saddr_dst *dst,
1230 			       int i)
1231 {
1232 	int ret;
1233 
1234 	if (i <= score->rule) {
1235 		switch (i) {
1236 		case IPV6_SADDR_RULE_SCOPE:
1237 			ret = score->scopedist;
1238 			break;
1239 		case IPV6_SADDR_RULE_PREFIX:
1240 			ret = score->matchlen;
1241 			break;
1242 		default:
1243 			ret = !!test_bit(i, score->scorebits);
1244 		}
1245 		goto out;
1246 	}
1247 
1248 	switch (i) {
1249 	case IPV6_SADDR_RULE_INIT:
1250 		/* Rule 0: remember if hiscore is not ready yet */
1251 		ret = !!score->ifa;
1252 		break;
1253 	case IPV6_SADDR_RULE_LOCAL:
1254 		/* Rule 1: Prefer same address */
1255 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1256 		break;
1257 	case IPV6_SADDR_RULE_SCOPE:
1258 		/* Rule 2: Prefer appropriate scope
1259 		 *
1260 		 *      ret
1261 		 *       ^
1262 		 *    -1 |  d 15
1263 		 *    ---+--+-+---> scope
1264 		 *       |
1265 		 *       |             d is scope of the destination.
1266 		 *  B-d  |  \
1267 		 *       |   \      <- smaller scope is better if
1268 		 *  B-15 |    \        if scope is enough for destination.
1269 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1270 		 * d-C-1 | /
1271 		 *       |/         <- greater is better
1272 		 *   -C  /             if scope is not enough for destination.
1273 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1274 		 *
1275 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1276 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1277 		 * Assume B = 0 and we get C > 29.
1278 		 */
1279 		ret = __ipv6_addr_src_scope(score->addr_type);
1280 		if (ret >= dst->scope)
1281 			ret = -ret;
1282 		else
1283 			ret -= 128;	/* 30 is enough */
1284 		score->scopedist = ret;
1285 		break;
1286 	case IPV6_SADDR_RULE_PREFERRED:
1287 	    {
1288 		/* Rule 3: Avoid deprecated and optimistic addresses */
1289 		u8 avoid = IFA_F_DEPRECATED;
1290 
1291 		if (!ipv6_use_optimistic_addr(score->ifa->idev))
1292 			avoid |= IFA_F_OPTIMISTIC;
1293 		ret = ipv6_saddr_preferred(score->addr_type) ||
1294 		      !(score->ifa->flags & avoid);
1295 		break;
1296 	    }
1297 #ifdef CONFIG_IPV6_MIP6
1298 	case IPV6_SADDR_RULE_HOA:
1299 	    {
1300 		/* Rule 4: Prefer home address */
1301 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1302 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1303 		break;
1304 	    }
1305 #endif
1306 	case IPV6_SADDR_RULE_OIF:
1307 		/* Rule 5: Prefer outgoing interface */
1308 		ret = (!dst->ifindex ||
1309 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1310 		break;
1311 	case IPV6_SADDR_RULE_LABEL:
1312 		/* Rule 6: Prefer matching label */
1313 		ret = ipv6_addr_label(net,
1314 				      &score->ifa->addr, score->addr_type,
1315 				      score->ifa->idev->dev->ifindex) == dst->label;
1316 		break;
1317 	case IPV6_SADDR_RULE_PRIVACY:
1318 	    {
1319 		/* Rule 7: Prefer public address
1320 		 * Note: prefer temporary address if use_tempaddr >= 2
1321 		 */
1322 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1323 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1324 				score->ifa->idev->cnf.use_tempaddr >= 2;
1325 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1326 		break;
1327 	    }
1328 	case IPV6_SADDR_RULE_ORCHID:
1329 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1330 		 *	    non-ORCHID vs non-ORCHID
1331 		 */
1332 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1333 			ipv6_addr_orchid(dst->addr));
1334 		break;
1335 	case IPV6_SADDR_RULE_PREFIX:
1336 		/* Rule 8: Use longest matching prefix */
1337 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1338 		if (ret > score->ifa->prefix_len)
1339 			ret = score->ifa->prefix_len;
1340 		score->matchlen = ret;
1341 		break;
1342 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1343 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1344 		/* Optimistic addresses still have lower precedence than other
1345 		 * preferred addresses.
1346 		 */
1347 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1348 		break;
1349 #endif
1350 	default:
1351 		ret = 0;
1352 	}
1353 
1354 	if (ret)
1355 		__set_bit(i, score->scorebits);
1356 	score->rule = i;
1357 out:
1358 	return ret;
1359 }
1360 
1361 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1362 		       const struct in6_addr *daddr, unsigned int prefs,
1363 		       struct in6_addr *saddr)
1364 {
1365 	struct ipv6_saddr_score scores[2],
1366 				*score = &scores[0], *hiscore = &scores[1];
1367 	struct ipv6_saddr_dst dst;
1368 	struct net_device *dev;
1369 	int dst_type;
1370 
1371 	dst_type = __ipv6_addr_type(daddr);
1372 	dst.addr = daddr;
1373 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1374 	dst.scope = __ipv6_addr_src_scope(dst_type);
1375 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1376 	dst.prefs = prefs;
1377 
1378 	hiscore->rule = -1;
1379 	hiscore->ifa = NULL;
1380 
1381 	rcu_read_lock();
1382 
1383 	for_each_netdev_rcu(net, dev) {
1384 		struct inet6_dev *idev;
1385 
1386 		/* Candidate Source Address (section 4)
1387 		 *  - multicast and link-local destination address,
1388 		 *    the set of candidate source address MUST only
1389 		 *    include addresses assigned to interfaces
1390 		 *    belonging to the same link as the outgoing
1391 		 *    interface.
1392 		 * (- For site-local destination addresses, the
1393 		 *    set of candidate source addresses MUST only
1394 		 *    include addresses assigned to interfaces
1395 		 *    belonging to the same site as the outgoing
1396 		 *    interface.)
1397 		 */
1398 		if (((dst_type & IPV6_ADDR_MULTICAST) ||
1399 		     dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) &&
1400 		    dst.ifindex && dev->ifindex != dst.ifindex)
1401 			continue;
1402 
1403 		idev = __in6_dev_get(dev);
1404 		if (!idev)
1405 			continue;
1406 
1407 		read_lock_bh(&idev->lock);
1408 		list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1409 			int i;
1410 
1411 			/*
1412 			 * - Tentative Address (RFC2462 section 5.4)
1413 			 *  - A tentative address is not considered
1414 			 *    "assigned to an interface" in the traditional
1415 			 *    sense, unless it is also flagged as optimistic.
1416 			 * - Candidate Source Address (section 4)
1417 			 *  - In any case, anycast addresses, multicast
1418 			 *    addresses, and the unspecified address MUST
1419 			 *    NOT be included in a candidate set.
1420 			 */
1421 			if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1422 			    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1423 				continue;
1424 
1425 			score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1426 
1427 			if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1428 				     score->addr_type & IPV6_ADDR_MULTICAST)) {
1429 				net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1430 						    dev->name);
1431 				continue;
1432 			}
1433 
1434 			score->rule = -1;
1435 			bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1436 
1437 			for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1438 				int minihiscore, miniscore;
1439 
1440 				minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
1441 				miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
1442 
1443 				if (minihiscore > miniscore) {
1444 					if (i == IPV6_SADDR_RULE_SCOPE &&
1445 					    score->scopedist > 0) {
1446 						/*
1447 						 * special case:
1448 						 * each remaining entry
1449 						 * has too small (not enough)
1450 						 * scope, because ifa entries
1451 						 * are sorted by their scope
1452 						 * values.
1453 						 */
1454 						goto try_nextdev;
1455 					}
1456 					break;
1457 				} else if (minihiscore < miniscore) {
1458 					if (hiscore->ifa)
1459 						in6_ifa_put(hiscore->ifa);
1460 
1461 					in6_ifa_hold(score->ifa);
1462 
1463 					swap(hiscore, score);
1464 
1465 					/* restore our iterator */
1466 					score->ifa = hiscore->ifa;
1467 
1468 					break;
1469 				}
1470 			}
1471 		}
1472 try_nextdev:
1473 		read_unlock_bh(&idev->lock);
1474 	}
1475 	rcu_read_unlock();
1476 
1477 	if (!hiscore->ifa)
1478 		return -EADDRNOTAVAIL;
1479 
1480 	*saddr = hiscore->ifa->addr;
1481 	in6_ifa_put(hiscore->ifa);
1482 	return 0;
1483 }
1484 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1485 
1486 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1487 		      u32 banned_flags)
1488 {
1489 	struct inet6_ifaddr *ifp;
1490 	int err = -EADDRNOTAVAIL;
1491 
1492 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1493 		if (ifp->scope > IFA_LINK)
1494 			break;
1495 		if (ifp->scope == IFA_LINK &&
1496 		    !(ifp->flags & banned_flags)) {
1497 			*addr = ifp->addr;
1498 			err = 0;
1499 			break;
1500 		}
1501 	}
1502 	return err;
1503 }
1504 
1505 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1506 		    u32 banned_flags)
1507 {
1508 	struct inet6_dev *idev;
1509 	int err = -EADDRNOTAVAIL;
1510 
1511 	rcu_read_lock();
1512 	idev = __in6_dev_get(dev);
1513 	if (idev) {
1514 		read_lock_bh(&idev->lock);
1515 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1516 		read_unlock_bh(&idev->lock);
1517 	}
1518 	rcu_read_unlock();
1519 	return err;
1520 }
1521 
1522 static int ipv6_count_addresses(struct inet6_dev *idev)
1523 {
1524 	int cnt = 0;
1525 	struct inet6_ifaddr *ifp;
1526 
1527 	read_lock_bh(&idev->lock);
1528 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1529 		cnt++;
1530 	read_unlock_bh(&idev->lock);
1531 	return cnt;
1532 }
1533 
1534 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1535 		  const struct net_device *dev, int strict)
1536 {
1537 	return ipv6_chk_addr_and_flags(net, addr, dev, strict, IFA_F_TENTATIVE);
1538 }
1539 EXPORT_SYMBOL(ipv6_chk_addr);
1540 
1541 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1542 			    const struct net_device *dev, int strict,
1543 			    u32 banned_flags)
1544 {
1545 	struct inet6_ifaddr *ifp;
1546 	unsigned int hash = inet6_addr_hash(addr);
1547 	u32 ifp_flags;
1548 
1549 	rcu_read_lock_bh();
1550 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1551 		if (!net_eq(dev_net(ifp->idev->dev), net))
1552 			continue;
1553 		/* Decouple optimistic from tentative for evaluation here.
1554 		 * Ban optimistic addresses explicitly, when required.
1555 		 */
1556 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1557 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1558 			    : ifp->flags;
1559 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1560 		    !(ifp_flags&banned_flags) &&
1561 		    (!dev || ifp->idev->dev == dev ||
1562 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1563 			rcu_read_unlock_bh();
1564 			return 1;
1565 		}
1566 	}
1567 
1568 	rcu_read_unlock_bh();
1569 	return 0;
1570 }
1571 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1572 
1573 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1574 			       struct net_device *dev)
1575 {
1576 	unsigned int hash = inet6_addr_hash(addr);
1577 	struct inet6_ifaddr *ifp;
1578 
1579 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1580 		if (!net_eq(dev_net(ifp->idev->dev), net))
1581 			continue;
1582 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1583 			if (!dev || ifp->idev->dev == dev)
1584 				return true;
1585 		}
1586 	}
1587 	return false;
1588 }
1589 
1590 /* Compares an address/prefix_len with addresses on device @dev.
1591  * If one is found it returns true.
1592  */
1593 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1594 	const unsigned int prefix_len, struct net_device *dev)
1595 {
1596 	struct inet6_dev *idev;
1597 	struct inet6_ifaddr *ifa;
1598 	bool ret = false;
1599 
1600 	rcu_read_lock();
1601 	idev = __in6_dev_get(dev);
1602 	if (idev) {
1603 		read_lock_bh(&idev->lock);
1604 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1605 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1606 			if (ret)
1607 				break;
1608 		}
1609 		read_unlock_bh(&idev->lock);
1610 	}
1611 	rcu_read_unlock();
1612 
1613 	return ret;
1614 }
1615 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1616 
1617 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1618 {
1619 	struct inet6_dev *idev;
1620 	struct inet6_ifaddr *ifa;
1621 	int	onlink;
1622 
1623 	onlink = 0;
1624 	rcu_read_lock();
1625 	idev = __in6_dev_get(dev);
1626 	if (idev) {
1627 		read_lock_bh(&idev->lock);
1628 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1629 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1630 						   ifa->prefix_len);
1631 			if (onlink)
1632 				break;
1633 		}
1634 		read_unlock_bh(&idev->lock);
1635 	}
1636 	rcu_read_unlock();
1637 	return onlink;
1638 }
1639 EXPORT_SYMBOL(ipv6_chk_prefix);
1640 
1641 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1642 				     struct net_device *dev, int strict)
1643 {
1644 	struct inet6_ifaddr *ifp, *result = NULL;
1645 	unsigned int hash = inet6_addr_hash(addr);
1646 
1647 	rcu_read_lock_bh();
1648 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
1649 		if (!net_eq(dev_net(ifp->idev->dev), net))
1650 			continue;
1651 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1652 			if (!dev || ifp->idev->dev == dev ||
1653 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1654 				result = ifp;
1655 				in6_ifa_hold(ifp);
1656 				break;
1657 			}
1658 		}
1659 	}
1660 	rcu_read_unlock_bh();
1661 
1662 	return result;
1663 }
1664 
1665 /* Gets referenced address, destroys ifaddr */
1666 
1667 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1668 {
1669 	if (ifp->flags&IFA_F_PERMANENT) {
1670 		spin_lock_bh(&ifp->lock);
1671 		addrconf_del_dad_work(ifp);
1672 		ifp->flags |= IFA_F_TENTATIVE;
1673 		if (dad_failed)
1674 			ifp->flags |= IFA_F_DADFAILED;
1675 		spin_unlock_bh(&ifp->lock);
1676 		if (dad_failed)
1677 			ipv6_ifa_notify(0, ifp);
1678 		in6_ifa_put(ifp);
1679 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1680 		struct inet6_ifaddr *ifpub;
1681 		spin_lock_bh(&ifp->lock);
1682 		ifpub = ifp->ifpub;
1683 		if (ifpub) {
1684 			in6_ifa_hold(ifpub);
1685 			spin_unlock_bh(&ifp->lock);
1686 			ipv6_create_tempaddr(ifpub, ifp);
1687 			in6_ifa_put(ifpub);
1688 		} else {
1689 			spin_unlock_bh(&ifp->lock);
1690 		}
1691 		ipv6_del_addr(ifp);
1692 	} else {
1693 		ipv6_del_addr(ifp);
1694 	}
1695 }
1696 
1697 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1698 {
1699 	int err = -ENOENT;
1700 
1701 	spin_lock_bh(&ifp->lock);
1702 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1703 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1704 		err = 0;
1705 	}
1706 	spin_unlock_bh(&ifp->lock);
1707 
1708 	return err;
1709 }
1710 
1711 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1712 {
1713 	struct in6_addr addr;
1714 	struct inet6_dev *idev = ifp->idev;
1715 	struct net *net = dev_net(ifp->idev->dev);
1716 
1717 	if (addrconf_dad_end(ifp)) {
1718 		in6_ifa_put(ifp);
1719 		return;
1720 	}
1721 
1722 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1723 			     ifp->idev->dev->name, &ifp->addr);
1724 
1725 	spin_lock_bh(&ifp->lock);
1726 
1727 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
1728 		int scope = ifp->scope;
1729 		u32 flags = ifp->flags;
1730 		struct in6_addr new_addr;
1731 		struct inet6_ifaddr *ifp2;
1732 		u32 valid_lft, preferred_lft;
1733 		int pfxlen = ifp->prefix_len;
1734 		int retries = ifp->stable_privacy_retry + 1;
1735 
1736 		if (retries > net->ipv6.sysctl.idgen_retries) {
1737 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
1738 					     ifp->idev->dev->name);
1739 			goto errdad;
1740 		}
1741 
1742 		new_addr = ifp->addr;
1743 		if (ipv6_generate_stable_address(&new_addr, retries,
1744 						 idev))
1745 			goto errdad;
1746 
1747 		valid_lft = ifp->valid_lft;
1748 		preferred_lft = ifp->prefered_lft;
1749 
1750 		spin_unlock_bh(&ifp->lock);
1751 
1752 		if (idev->cnf.max_addresses &&
1753 		    ipv6_count_addresses(idev) >=
1754 		    idev->cnf.max_addresses)
1755 			goto lock_errdad;
1756 
1757 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
1758 				     ifp->idev->dev->name);
1759 
1760 		ifp2 = ipv6_add_addr(idev, &new_addr, NULL, pfxlen,
1761 				     scope, flags, valid_lft,
1762 				     preferred_lft);
1763 		if (IS_ERR(ifp2))
1764 			goto lock_errdad;
1765 
1766 		spin_lock_bh(&ifp2->lock);
1767 		ifp2->stable_privacy_retry = retries;
1768 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
1769 		spin_unlock_bh(&ifp2->lock);
1770 
1771 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
1772 		in6_ifa_put(ifp2);
1773 lock_errdad:
1774 		spin_lock_bh(&ifp->lock);
1775 	} else if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1776 		addr.s6_addr32[0] = htonl(0xfe800000);
1777 		addr.s6_addr32[1] = 0;
1778 
1779 		if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1780 		    ipv6_addr_equal(&ifp->addr, &addr)) {
1781 			/* DAD failed for link-local based on MAC address */
1782 			idev->cnf.disable_ipv6 = 1;
1783 
1784 			pr_info("%s: IPv6 being disabled!\n",
1785 				ifp->idev->dev->name);
1786 		}
1787 	}
1788 
1789 errdad:
1790 	/* transition from _POSTDAD to _ERRDAD */
1791 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
1792 	spin_unlock_bh(&ifp->lock);
1793 
1794 	addrconf_mod_dad_work(ifp, 0);
1795 }
1796 
1797 /* Join to solicited addr multicast group.
1798  * caller must hold RTNL */
1799 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
1800 {
1801 	struct in6_addr maddr;
1802 
1803 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1804 		return;
1805 
1806 	addrconf_addr_solict_mult(addr, &maddr);
1807 	ipv6_dev_mc_inc(dev, &maddr);
1808 }
1809 
1810 /* caller must hold RTNL */
1811 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
1812 {
1813 	struct in6_addr maddr;
1814 
1815 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1816 		return;
1817 
1818 	addrconf_addr_solict_mult(addr, &maddr);
1819 	__ipv6_dev_mc_dec(idev, &maddr);
1820 }
1821 
1822 /* caller must hold RTNL */
1823 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1824 {
1825 	struct in6_addr addr;
1826 
1827 	if (ifp->prefix_len >= 127) /* RFC 6164 */
1828 		return;
1829 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1830 	if (ipv6_addr_any(&addr))
1831 		return;
1832 	__ipv6_dev_ac_inc(ifp->idev, &addr);
1833 }
1834 
1835 /* caller must hold RTNL */
1836 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1837 {
1838 	struct in6_addr addr;
1839 
1840 	if (ifp->prefix_len >= 127) /* RFC 6164 */
1841 		return;
1842 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1843 	if (ipv6_addr_any(&addr))
1844 		return;
1845 	__ipv6_dev_ac_dec(ifp->idev, &addr);
1846 }
1847 
1848 static int addrconf_ifid_eui64(u8 *eui, struct net_device *dev)
1849 {
1850 	if (dev->addr_len != IEEE802154_ADDR_LEN)
1851 		return -1;
1852 	memcpy(eui, dev->dev_addr, 8);
1853 	eui[0] ^= 2;
1854 	return 0;
1855 }
1856 
1857 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
1858 {
1859 	union fwnet_hwaddr *ha;
1860 
1861 	if (dev->addr_len != FWNET_ALEN)
1862 		return -1;
1863 
1864 	ha = (union fwnet_hwaddr *)dev->dev_addr;
1865 
1866 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
1867 	eui[0] ^= 2;
1868 	return 0;
1869 }
1870 
1871 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
1872 {
1873 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
1874 	if (dev->addr_len != ARCNET_ALEN)
1875 		return -1;
1876 	memset(eui, 0, 7);
1877 	eui[7] = *(u8 *)dev->dev_addr;
1878 	return 0;
1879 }
1880 
1881 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
1882 {
1883 	if (dev->addr_len != INFINIBAND_ALEN)
1884 		return -1;
1885 	memcpy(eui, dev->dev_addr + 12, 8);
1886 	eui[0] |= 2;
1887 	return 0;
1888 }
1889 
1890 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
1891 {
1892 	if (addr == 0)
1893 		return -1;
1894 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
1895 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
1896 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
1897 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
1898 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
1899 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
1900 	eui[1] = 0;
1901 	eui[2] = 0x5E;
1902 	eui[3] = 0xFE;
1903 	memcpy(eui + 4, &addr, 4);
1904 	return 0;
1905 }
1906 
1907 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
1908 {
1909 	if (dev->priv_flags & IFF_ISATAP)
1910 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1911 	return -1;
1912 }
1913 
1914 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
1915 {
1916 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1917 }
1918 
1919 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
1920 {
1921 	memcpy(eui, dev->perm_addr, 3);
1922 	memcpy(eui + 5, dev->perm_addr + 3, 3);
1923 	eui[3] = 0xFF;
1924 	eui[4] = 0xFE;
1925 	eui[0] ^= 2;
1926 	return 0;
1927 }
1928 
1929 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
1930 {
1931 	switch (dev->type) {
1932 	case ARPHRD_ETHER:
1933 	case ARPHRD_FDDI:
1934 		return addrconf_ifid_eui48(eui, dev);
1935 	case ARPHRD_ARCNET:
1936 		return addrconf_ifid_arcnet(eui, dev);
1937 	case ARPHRD_INFINIBAND:
1938 		return addrconf_ifid_infiniband(eui, dev);
1939 	case ARPHRD_SIT:
1940 		return addrconf_ifid_sit(eui, dev);
1941 	case ARPHRD_IPGRE:
1942 		return addrconf_ifid_gre(eui, dev);
1943 	case ARPHRD_6LOWPAN:
1944 	case ARPHRD_IEEE802154:
1945 		return addrconf_ifid_eui64(eui, dev);
1946 	case ARPHRD_IEEE1394:
1947 		return addrconf_ifid_ieee1394(eui, dev);
1948 	case ARPHRD_TUNNEL6:
1949 		return addrconf_ifid_ip6tnl(eui, dev);
1950 	}
1951 	return -1;
1952 }
1953 
1954 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
1955 {
1956 	int err = -1;
1957 	struct inet6_ifaddr *ifp;
1958 
1959 	read_lock_bh(&idev->lock);
1960 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1961 		if (ifp->scope > IFA_LINK)
1962 			break;
1963 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
1964 			memcpy(eui, ifp->addr.s6_addr+8, 8);
1965 			err = 0;
1966 			break;
1967 		}
1968 	}
1969 	read_unlock_bh(&idev->lock);
1970 	return err;
1971 }
1972 
1973 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
1974 static void __ipv6_regen_rndid(struct inet6_dev *idev)
1975 {
1976 regen:
1977 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
1978 	idev->rndid[0] &= ~0x02;
1979 
1980 	/*
1981 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
1982 	 * check if generated address is not inappropriate
1983 	 *
1984 	 *  - Reserved subnet anycast (RFC 2526)
1985 	 *	11111101 11....11 1xxxxxxx
1986 	 *  - ISATAP (RFC4214) 6.1
1987 	 *	00-00-5E-FE-xx-xx-xx-xx
1988 	 *  - value 0
1989 	 *  - XXX: already assigned to an address on the device
1990 	 */
1991 	if (idev->rndid[0] == 0xfd &&
1992 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
1993 	    (idev->rndid[7]&0x80))
1994 		goto regen;
1995 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
1996 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
1997 			goto regen;
1998 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
1999 			goto regen;
2000 	}
2001 }
2002 
2003 static void ipv6_regen_rndid(unsigned long data)
2004 {
2005 	struct inet6_dev *idev = (struct inet6_dev *) data;
2006 	unsigned long expires;
2007 
2008 	rcu_read_lock_bh();
2009 	write_lock_bh(&idev->lock);
2010 
2011 	if (idev->dead)
2012 		goto out;
2013 
2014 	__ipv6_regen_rndid(idev);
2015 
2016 	expires = jiffies +
2017 		idev->cnf.temp_prefered_lft * HZ -
2018 		idev->cnf.regen_max_retry * idev->cnf.dad_transmits *
2019 		NEIGH_VAR(idev->nd_parms, RETRANS_TIME) -
2020 		idev->cnf.max_desync_factor * HZ;
2021 	if (time_before(expires, jiffies)) {
2022 		pr_warn("%s: too short regeneration interval; timer disabled for %s\n",
2023 			__func__, idev->dev->name);
2024 		goto out;
2025 	}
2026 
2027 	if (!mod_timer(&idev->regen_timer, expires))
2028 		in6_dev_hold(idev);
2029 
2030 out:
2031 	write_unlock_bh(&idev->lock);
2032 	rcu_read_unlock_bh();
2033 	in6_dev_put(idev);
2034 }
2035 
2036 static void  __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2037 {
2038 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2039 		__ipv6_regen_rndid(idev);
2040 }
2041 
2042 /*
2043  *	Add prefix route.
2044  */
2045 
2046 static void
2047 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
2048 		      unsigned long expires, u32 flags)
2049 {
2050 	struct fib6_config cfg = {
2051 		.fc_table = RT6_TABLE_PREFIX,
2052 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2053 		.fc_ifindex = dev->ifindex,
2054 		.fc_expires = expires,
2055 		.fc_dst_len = plen,
2056 		.fc_flags = RTF_UP | flags,
2057 		.fc_nlinfo.nl_net = dev_net(dev),
2058 		.fc_protocol = RTPROT_KERNEL,
2059 	};
2060 
2061 	cfg.fc_dst = *pfx;
2062 
2063 	/* Prevent useless cloning on PtP SIT.
2064 	   This thing is done here expecting that the whole
2065 	   class of non-broadcast devices need not cloning.
2066 	 */
2067 #if IS_ENABLED(CONFIG_IPV6_SIT)
2068 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2069 		cfg.fc_flags |= RTF_NONEXTHOP;
2070 #endif
2071 
2072 	ip6_route_add(&cfg);
2073 }
2074 
2075 
2076 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2077 						  int plen,
2078 						  const struct net_device *dev,
2079 						  u32 flags, u32 noflags)
2080 {
2081 	struct fib6_node *fn;
2082 	struct rt6_info *rt = NULL;
2083 	struct fib6_table *table;
2084 
2085 	table = fib6_get_table(dev_net(dev), RT6_TABLE_PREFIX);
2086 	if (!table)
2087 		return NULL;
2088 
2089 	read_lock_bh(&table->tb6_lock);
2090 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
2091 	if (!fn)
2092 		goto out;
2093 
2094 	noflags |= RTF_CACHE;
2095 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2096 		if (rt->dst.dev->ifindex != dev->ifindex)
2097 			continue;
2098 		if ((rt->rt6i_flags & flags) != flags)
2099 			continue;
2100 		if ((rt->rt6i_flags & noflags) != 0)
2101 			continue;
2102 		dst_hold(&rt->dst);
2103 		break;
2104 	}
2105 out:
2106 	read_unlock_bh(&table->tb6_lock);
2107 	return rt;
2108 }
2109 
2110 
2111 /* Create "default" multicast route to the interface */
2112 
2113 static void addrconf_add_mroute(struct net_device *dev)
2114 {
2115 	struct fib6_config cfg = {
2116 		.fc_table = RT6_TABLE_LOCAL,
2117 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2118 		.fc_ifindex = dev->ifindex,
2119 		.fc_dst_len = 8,
2120 		.fc_flags = RTF_UP,
2121 		.fc_nlinfo.nl_net = dev_net(dev),
2122 	};
2123 
2124 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2125 
2126 	ip6_route_add(&cfg);
2127 }
2128 
2129 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2130 {
2131 	struct inet6_dev *idev;
2132 
2133 	ASSERT_RTNL();
2134 
2135 	idev = ipv6_find_idev(dev);
2136 	if (!idev)
2137 		return ERR_PTR(-ENOBUFS);
2138 
2139 	if (idev->cnf.disable_ipv6)
2140 		return ERR_PTR(-EACCES);
2141 
2142 	/* Add default multicast route */
2143 	if (!(dev->flags & IFF_LOOPBACK))
2144 		addrconf_add_mroute(dev);
2145 
2146 	return idev;
2147 }
2148 
2149 static void manage_tempaddrs(struct inet6_dev *idev,
2150 			     struct inet6_ifaddr *ifp,
2151 			     __u32 valid_lft, __u32 prefered_lft,
2152 			     bool create, unsigned long now)
2153 {
2154 	u32 flags;
2155 	struct inet6_ifaddr *ift;
2156 
2157 	read_lock_bh(&idev->lock);
2158 	/* update all temporary addresses in the list */
2159 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2160 		int age, max_valid, max_prefered;
2161 
2162 		if (ifp != ift->ifpub)
2163 			continue;
2164 
2165 		/* RFC 4941 section 3.3:
2166 		 * If a received option will extend the lifetime of a public
2167 		 * address, the lifetimes of temporary addresses should
2168 		 * be extended, subject to the overall constraint that no
2169 		 * temporary addresses should ever remain "valid" or "preferred"
2170 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2171 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2172 		 */
2173 		age = (now - ift->cstamp) / HZ;
2174 		max_valid = idev->cnf.temp_valid_lft - age;
2175 		if (max_valid < 0)
2176 			max_valid = 0;
2177 
2178 		max_prefered = idev->cnf.temp_prefered_lft -
2179 			       idev->cnf.max_desync_factor - age;
2180 		if (max_prefered < 0)
2181 			max_prefered = 0;
2182 
2183 		if (valid_lft > max_valid)
2184 			valid_lft = max_valid;
2185 
2186 		if (prefered_lft > max_prefered)
2187 			prefered_lft = max_prefered;
2188 
2189 		spin_lock(&ift->lock);
2190 		flags = ift->flags;
2191 		ift->valid_lft = valid_lft;
2192 		ift->prefered_lft = prefered_lft;
2193 		ift->tstamp = now;
2194 		if (prefered_lft > 0)
2195 			ift->flags &= ~IFA_F_DEPRECATED;
2196 
2197 		spin_unlock(&ift->lock);
2198 		if (!(flags&IFA_F_TENTATIVE))
2199 			ipv6_ifa_notify(0, ift);
2200 	}
2201 
2202 	if ((create || list_empty(&idev->tempaddr_list)) &&
2203 	    idev->cnf.use_tempaddr > 0) {
2204 		/* When a new public address is created as described
2205 		 * in [ADDRCONF], also create a new temporary address.
2206 		 * Also create a temporary address if it's enabled but
2207 		 * no temporary address currently exists.
2208 		 */
2209 		read_unlock_bh(&idev->lock);
2210 		ipv6_create_tempaddr(ifp, NULL);
2211 	} else {
2212 		read_unlock_bh(&idev->lock);
2213 	}
2214 }
2215 
2216 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2217 {
2218 	struct prefix_info *pinfo;
2219 	__u32 valid_lft;
2220 	__u32 prefered_lft;
2221 	int addr_type;
2222 	u32 addr_flags = 0;
2223 	struct inet6_dev *in6_dev;
2224 	struct net *net = dev_net(dev);
2225 
2226 	pinfo = (struct prefix_info *) opt;
2227 
2228 	if (len < sizeof(struct prefix_info)) {
2229 		ADBG("addrconf: prefix option too short\n");
2230 		return;
2231 	}
2232 
2233 	/*
2234 	 *	Validation checks ([ADDRCONF], page 19)
2235 	 */
2236 
2237 	addr_type = ipv6_addr_type(&pinfo->prefix);
2238 
2239 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2240 		return;
2241 
2242 	valid_lft = ntohl(pinfo->valid);
2243 	prefered_lft = ntohl(pinfo->prefered);
2244 
2245 	if (prefered_lft > valid_lft) {
2246 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2247 		return;
2248 	}
2249 
2250 	in6_dev = in6_dev_get(dev);
2251 
2252 	if (!in6_dev) {
2253 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2254 				    dev->name);
2255 		return;
2256 	}
2257 
2258 	/*
2259 	 *	Two things going on here:
2260 	 *	1) Add routes for on-link prefixes
2261 	 *	2) Configure prefixes with the auto flag set
2262 	 */
2263 
2264 	if (pinfo->onlink) {
2265 		struct rt6_info *rt;
2266 		unsigned long rt_expires;
2267 
2268 		/* Avoid arithmetic overflow. Really, we could
2269 		 * save rt_expires in seconds, likely valid_lft,
2270 		 * but it would require division in fib gc, that it
2271 		 * not good.
2272 		 */
2273 		if (HZ > USER_HZ)
2274 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2275 		else
2276 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2277 
2278 		if (addrconf_finite_timeout(rt_expires))
2279 			rt_expires *= HZ;
2280 
2281 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2282 					       pinfo->prefix_len,
2283 					       dev,
2284 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2285 					       RTF_GATEWAY | RTF_DEFAULT);
2286 
2287 		if (rt) {
2288 			/* Autoconf prefix route */
2289 			if (valid_lft == 0) {
2290 				ip6_del_rt(rt);
2291 				rt = NULL;
2292 			} else if (addrconf_finite_timeout(rt_expires)) {
2293 				/* not infinity */
2294 				rt6_set_expires(rt, jiffies + rt_expires);
2295 			} else {
2296 				rt6_clean_expires(rt);
2297 			}
2298 		} else if (valid_lft) {
2299 			clock_t expires = 0;
2300 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2301 			if (addrconf_finite_timeout(rt_expires)) {
2302 				/* not infinity */
2303 				flags |= RTF_EXPIRES;
2304 				expires = jiffies_to_clock_t(rt_expires);
2305 			}
2306 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2307 					      dev, expires, flags);
2308 		}
2309 		ip6_rt_put(rt);
2310 	}
2311 
2312 	/* Try to figure out our local address for this prefix */
2313 
2314 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2315 		struct inet6_ifaddr *ifp;
2316 		struct in6_addr addr;
2317 		int create = 0, update_lft = 0;
2318 		bool tokenized = false;
2319 
2320 		if (pinfo->prefix_len == 64) {
2321 			memcpy(&addr, &pinfo->prefix, 8);
2322 
2323 			if (!ipv6_addr_any(&in6_dev->token)) {
2324 				read_lock_bh(&in6_dev->lock);
2325 				memcpy(addr.s6_addr + 8,
2326 				       in6_dev->token.s6_addr + 8, 8);
2327 				read_unlock_bh(&in6_dev->lock);
2328 				tokenized = true;
2329 			} else if (in6_dev->addr_gen_mode ==
2330 				   IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
2331 				   !ipv6_generate_stable_address(&addr, 0,
2332 								 in6_dev)) {
2333 				addr_flags |= IFA_F_STABLE_PRIVACY;
2334 				goto ok;
2335 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2336 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2337 				in6_dev_put(in6_dev);
2338 				return;
2339 			}
2340 			goto ok;
2341 		}
2342 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2343 				    pinfo->prefix_len);
2344 		in6_dev_put(in6_dev);
2345 		return;
2346 
2347 ok:
2348 
2349 		ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
2350 
2351 		if (!ifp && valid_lft) {
2352 			int max_addresses = in6_dev->cnf.max_addresses;
2353 
2354 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2355 			if (in6_dev->cnf.optimistic_dad &&
2356 			    !net->ipv6.devconf_all->forwarding && sllao)
2357 				addr_flags = IFA_F_OPTIMISTIC;
2358 #endif
2359 
2360 			/* Do not allow to create too much of autoconfigured
2361 			 * addresses; this would be too easy way to crash kernel.
2362 			 */
2363 			if (!max_addresses ||
2364 			    ipv6_count_addresses(in6_dev) < max_addresses)
2365 				ifp = ipv6_add_addr(in6_dev, &addr, NULL,
2366 						    pinfo->prefix_len,
2367 						    addr_type&IPV6_ADDR_SCOPE_MASK,
2368 						    addr_flags, valid_lft,
2369 						    prefered_lft);
2370 
2371 			if (IS_ERR_OR_NULL(ifp)) {
2372 				in6_dev_put(in6_dev);
2373 				return;
2374 			}
2375 
2376 			update_lft = 0;
2377 			create = 1;
2378 			spin_lock_bh(&ifp->lock);
2379 			ifp->flags |= IFA_F_MANAGETEMPADDR;
2380 			ifp->cstamp = jiffies;
2381 			ifp->tokenized = tokenized;
2382 			spin_unlock_bh(&ifp->lock);
2383 			addrconf_dad_start(ifp);
2384 		}
2385 
2386 		if (ifp) {
2387 			u32 flags;
2388 			unsigned long now;
2389 			u32 stored_lft;
2390 
2391 			/* update lifetime (RFC2462 5.5.3 e) */
2392 			spin_lock_bh(&ifp->lock);
2393 			now = jiffies;
2394 			if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2395 				stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2396 			else
2397 				stored_lft = 0;
2398 			if (!update_lft && !create && stored_lft) {
2399 				const u32 minimum_lft = min_t(u32,
2400 					stored_lft, MIN_VALID_LIFETIME);
2401 				valid_lft = max(valid_lft, minimum_lft);
2402 
2403 				/* RFC4862 Section 5.5.3e:
2404 				 * "Note that the preferred lifetime of the
2405 				 *  corresponding address is always reset to
2406 				 *  the Preferred Lifetime in the received
2407 				 *  Prefix Information option, regardless of
2408 				 *  whether the valid lifetime is also reset or
2409 				 *  ignored."
2410 				 *
2411 				 * So we should always update prefered_lft here.
2412 				 */
2413 				update_lft = 1;
2414 			}
2415 
2416 			if (update_lft) {
2417 				ifp->valid_lft = valid_lft;
2418 				ifp->prefered_lft = prefered_lft;
2419 				ifp->tstamp = now;
2420 				flags = ifp->flags;
2421 				ifp->flags &= ~IFA_F_DEPRECATED;
2422 				spin_unlock_bh(&ifp->lock);
2423 
2424 				if (!(flags&IFA_F_TENTATIVE))
2425 					ipv6_ifa_notify(0, ifp);
2426 			} else
2427 				spin_unlock_bh(&ifp->lock);
2428 
2429 			manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2430 					 create, now);
2431 
2432 			in6_ifa_put(ifp);
2433 			addrconf_verify();
2434 		}
2435 	}
2436 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2437 	in6_dev_put(in6_dev);
2438 }
2439 
2440 /*
2441  *	Set destination address.
2442  *	Special case for SIT interfaces where we create a new "virtual"
2443  *	device.
2444  */
2445 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2446 {
2447 	struct in6_ifreq ireq;
2448 	struct net_device *dev;
2449 	int err = -EINVAL;
2450 
2451 	rtnl_lock();
2452 
2453 	err = -EFAULT;
2454 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2455 		goto err_exit;
2456 
2457 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2458 
2459 	err = -ENODEV;
2460 	if (!dev)
2461 		goto err_exit;
2462 
2463 #if IS_ENABLED(CONFIG_IPV6_SIT)
2464 	if (dev->type == ARPHRD_SIT) {
2465 		const struct net_device_ops *ops = dev->netdev_ops;
2466 		struct ifreq ifr;
2467 		struct ip_tunnel_parm p;
2468 
2469 		err = -EADDRNOTAVAIL;
2470 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2471 			goto err_exit;
2472 
2473 		memset(&p, 0, sizeof(p));
2474 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2475 		p.iph.saddr = 0;
2476 		p.iph.version = 4;
2477 		p.iph.ihl = 5;
2478 		p.iph.protocol = IPPROTO_IPV6;
2479 		p.iph.ttl = 64;
2480 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2481 
2482 		if (ops->ndo_do_ioctl) {
2483 			mm_segment_t oldfs = get_fs();
2484 
2485 			set_fs(KERNEL_DS);
2486 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2487 			set_fs(oldfs);
2488 		} else
2489 			err = -EOPNOTSUPP;
2490 
2491 		if (err == 0) {
2492 			err = -ENOBUFS;
2493 			dev = __dev_get_by_name(net, p.name);
2494 			if (!dev)
2495 				goto err_exit;
2496 			err = dev_open(dev);
2497 		}
2498 	}
2499 #endif
2500 
2501 err_exit:
2502 	rtnl_unlock();
2503 	return err;
2504 }
2505 
2506 static int ipv6_mc_config(struct sock *sk, bool join,
2507 			  const struct in6_addr *addr, int ifindex)
2508 {
2509 	int ret;
2510 
2511 	ASSERT_RTNL();
2512 
2513 	lock_sock(sk);
2514 	if (join)
2515 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2516 	else
2517 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2518 	release_sock(sk);
2519 
2520 	return ret;
2521 }
2522 
2523 /*
2524  *	Manual configuration of address on an interface
2525  */
2526 static int inet6_addr_add(struct net *net, int ifindex,
2527 			  const struct in6_addr *pfx,
2528 			  const struct in6_addr *peer_pfx,
2529 			  unsigned int plen, __u32 ifa_flags,
2530 			  __u32 prefered_lft, __u32 valid_lft)
2531 {
2532 	struct inet6_ifaddr *ifp;
2533 	struct inet6_dev *idev;
2534 	struct net_device *dev;
2535 	unsigned long timeout;
2536 	clock_t expires;
2537 	int scope;
2538 	u32 flags;
2539 
2540 	ASSERT_RTNL();
2541 
2542 	if (plen > 128)
2543 		return -EINVAL;
2544 
2545 	/* check the lifetime */
2546 	if (!valid_lft || prefered_lft > valid_lft)
2547 		return -EINVAL;
2548 
2549 	if (ifa_flags & IFA_F_MANAGETEMPADDR && plen != 64)
2550 		return -EINVAL;
2551 
2552 	dev = __dev_get_by_index(net, ifindex);
2553 	if (!dev)
2554 		return -ENODEV;
2555 
2556 	idev = addrconf_add_dev(dev);
2557 	if (IS_ERR(idev))
2558 		return PTR_ERR(idev);
2559 
2560 	if (ifa_flags & IFA_F_MCAUTOJOIN) {
2561 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2562 					 true, pfx, ifindex);
2563 
2564 		if (ret < 0)
2565 			return ret;
2566 	}
2567 
2568 	scope = ipv6_addr_scope(pfx);
2569 
2570 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2571 	if (addrconf_finite_timeout(timeout)) {
2572 		expires = jiffies_to_clock_t(timeout * HZ);
2573 		valid_lft = timeout;
2574 		flags = RTF_EXPIRES;
2575 	} else {
2576 		expires = 0;
2577 		flags = 0;
2578 		ifa_flags |= IFA_F_PERMANENT;
2579 	}
2580 
2581 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2582 	if (addrconf_finite_timeout(timeout)) {
2583 		if (timeout == 0)
2584 			ifa_flags |= IFA_F_DEPRECATED;
2585 		prefered_lft = timeout;
2586 	}
2587 
2588 	ifp = ipv6_add_addr(idev, pfx, peer_pfx, plen, scope, ifa_flags,
2589 			    valid_lft, prefered_lft);
2590 
2591 	if (!IS_ERR(ifp)) {
2592 		if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
2593 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2594 					      expires, flags);
2595 		}
2596 
2597 		/*
2598 		 * Note that section 3.1 of RFC 4429 indicates
2599 		 * that the Optimistic flag should not be set for
2600 		 * manually configured addresses
2601 		 */
2602 		addrconf_dad_start(ifp);
2603 		if (ifa_flags & IFA_F_MANAGETEMPADDR)
2604 			manage_tempaddrs(idev, ifp, valid_lft, prefered_lft,
2605 					 true, jiffies);
2606 		in6_ifa_put(ifp);
2607 		addrconf_verify_rtnl();
2608 		return 0;
2609 	} else if (ifa_flags & IFA_F_MCAUTOJOIN) {
2610 		ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2611 			       false, pfx, ifindex);
2612 	}
2613 
2614 	return PTR_ERR(ifp);
2615 }
2616 
2617 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2618 			  const struct in6_addr *pfx, unsigned int plen)
2619 {
2620 	struct inet6_ifaddr *ifp;
2621 	struct inet6_dev *idev;
2622 	struct net_device *dev;
2623 
2624 	if (plen > 128)
2625 		return -EINVAL;
2626 
2627 	dev = __dev_get_by_index(net, ifindex);
2628 	if (!dev)
2629 		return -ENODEV;
2630 
2631 	idev = __in6_dev_get(dev);
2632 	if (!idev)
2633 		return -ENXIO;
2634 
2635 	read_lock_bh(&idev->lock);
2636 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2637 		if (ifp->prefix_len == plen &&
2638 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2639 			in6_ifa_hold(ifp);
2640 			read_unlock_bh(&idev->lock);
2641 
2642 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
2643 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
2644 				manage_tempaddrs(idev, ifp, 0, 0, false,
2645 						 jiffies);
2646 			ipv6_del_addr(ifp);
2647 			addrconf_verify_rtnl();
2648 			if (ipv6_addr_is_multicast(pfx)) {
2649 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2650 					       false, pfx, dev->ifindex);
2651 			}
2652 			return 0;
2653 		}
2654 	}
2655 	read_unlock_bh(&idev->lock);
2656 	return -EADDRNOTAVAIL;
2657 }
2658 
2659 
2660 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2661 {
2662 	struct in6_ifreq ireq;
2663 	int err;
2664 
2665 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2666 		return -EPERM;
2667 
2668 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2669 		return -EFAULT;
2670 
2671 	rtnl_lock();
2672 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr, NULL,
2673 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2674 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2675 	rtnl_unlock();
2676 	return err;
2677 }
2678 
2679 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2680 {
2681 	struct in6_ifreq ireq;
2682 	int err;
2683 
2684 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2685 		return -EPERM;
2686 
2687 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2688 		return -EFAULT;
2689 
2690 	rtnl_lock();
2691 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
2692 			     ireq.ifr6_prefixlen);
2693 	rtnl_unlock();
2694 	return err;
2695 }
2696 
2697 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2698 		     int plen, int scope)
2699 {
2700 	struct inet6_ifaddr *ifp;
2701 
2702 	ifp = ipv6_add_addr(idev, addr, NULL, plen,
2703 			    scope, IFA_F_PERMANENT,
2704 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2705 	if (!IS_ERR(ifp)) {
2706 		spin_lock_bh(&ifp->lock);
2707 		ifp->flags &= ~IFA_F_TENTATIVE;
2708 		spin_unlock_bh(&ifp->lock);
2709 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2710 		in6_ifa_put(ifp);
2711 	}
2712 }
2713 
2714 #if IS_ENABLED(CONFIG_IPV6_SIT)
2715 static void sit_add_v4_addrs(struct inet6_dev *idev)
2716 {
2717 	struct in6_addr addr;
2718 	struct net_device *dev;
2719 	struct net *net = dev_net(idev->dev);
2720 	int scope, plen;
2721 	u32 pflags = 0;
2722 
2723 	ASSERT_RTNL();
2724 
2725 	memset(&addr, 0, sizeof(struct in6_addr));
2726 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2727 
2728 	if (idev->dev->flags&IFF_POINTOPOINT) {
2729 		addr.s6_addr32[0] = htonl(0xfe800000);
2730 		scope = IFA_LINK;
2731 		plen = 64;
2732 	} else {
2733 		scope = IPV6_ADDR_COMPATv4;
2734 		plen = 96;
2735 		pflags |= RTF_NONEXTHOP;
2736 	}
2737 
2738 	if (addr.s6_addr32[3]) {
2739 		add_addr(idev, &addr, plen, scope);
2740 		addrconf_prefix_route(&addr, plen, idev->dev, 0, pflags);
2741 		return;
2742 	}
2743 
2744 	for_each_netdev(net, dev) {
2745 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
2746 		if (in_dev && (dev->flags & IFF_UP)) {
2747 			struct in_ifaddr *ifa;
2748 
2749 			int flag = scope;
2750 
2751 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2752 
2753 				addr.s6_addr32[3] = ifa->ifa_local;
2754 
2755 				if (ifa->ifa_scope == RT_SCOPE_LINK)
2756 					continue;
2757 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2758 					if (idev->dev->flags&IFF_POINTOPOINT)
2759 						continue;
2760 					flag |= IFA_HOST;
2761 				}
2762 
2763 				add_addr(idev, &addr, plen, flag);
2764 				addrconf_prefix_route(&addr, plen, idev->dev, 0,
2765 						      pflags);
2766 			}
2767 		}
2768 	}
2769 }
2770 #endif
2771 
2772 static void init_loopback(struct net_device *dev)
2773 {
2774 	struct inet6_dev  *idev;
2775 	struct net_device *sp_dev;
2776 	struct inet6_ifaddr *sp_ifa;
2777 	struct rt6_info *sp_rt;
2778 
2779 	/* ::1 */
2780 
2781 	ASSERT_RTNL();
2782 
2783 	idev = ipv6_find_idev(dev);
2784 	if (!idev) {
2785 		pr_debug("%s: add_dev failed\n", __func__);
2786 		return;
2787 	}
2788 
2789 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2790 
2791 	/* Add routes to other interface's IPv6 addresses */
2792 	for_each_netdev(dev_net(dev), sp_dev) {
2793 		if (!strcmp(sp_dev->name, dev->name))
2794 			continue;
2795 
2796 		idev = __in6_dev_get(sp_dev);
2797 		if (!idev)
2798 			continue;
2799 
2800 		read_lock_bh(&idev->lock);
2801 		list_for_each_entry(sp_ifa, &idev->addr_list, if_list) {
2802 
2803 			if (sp_ifa->flags & (IFA_F_DADFAILED | IFA_F_TENTATIVE))
2804 				continue;
2805 
2806 			if (sp_ifa->rt) {
2807 				/* This dst has been added to garbage list when
2808 				 * lo device down, release this obsolete dst and
2809 				 * reallocate a new router for ifa.
2810 				 */
2811 				if (sp_ifa->rt->dst.obsolete > 0) {
2812 					ip6_rt_put(sp_ifa->rt);
2813 					sp_ifa->rt = NULL;
2814 				} else {
2815 					continue;
2816 				}
2817 			}
2818 
2819 			sp_rt = addrconf_dst_alloc(idev, &sp_ifa->addr, false);
2820 
2821 			/* Failure cases are ignored */
2822 			if (!IS_ERR(sp_rt)) {
2823 				sp_ifa->rt = sp_rt;
2824 				ip6_ins_rt(sp_rt);
2825 			}
2826 		}
2827 		read_unlock_bh(&idev->lock);
2828 	}
2829 }
2830 
2831 static void addrconf_add_linklocal(struct inet6_dev *idev,
2832 				   const struct in6_addr *addr, u32 flags)
2833 {
2834 	struct inet6_ifaddr *ifp;
2835 	u32 addr_flags = flags | IFA_F_PERMANENT;
2836 
2837 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2838 	if (idev->cnf.optimistic_dad &&
2839 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
2840 		addr_flags |= IFA_F_OPTIMISTIC;
2841 #endif
2842 
2843 	ifp = ipv6_add_addr(idev, addr, NULL, 64, IFA_LINK, addr_flags,
2844 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2845 	if (!IS_ERR(ifp)) {
2846 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
2847 		addrconf_dad_start(ifp);
2848 		in6_ifa_put(ifp);
2849 	}
2850 }
2851 
2852 static bool ipv6_reserved_interfaceid(struct in6_addr address)
2853 {
2854 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
2855 		return true;
2856 
2857 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
2858 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
2859 		return true;
2860 
2861 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
2862 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
2863 		return true;
2864 
2865 	return false;
2866 }
2867 
2868 static int ipv6_generate_stable_address(struct in6_addr *address,
2869 					u8 dad_count,
2870 					const struct inet6_dev *idev)
2871 {
2872 	static DEFINE_SPINLOCK(lock);
2873 	static __u32 digest[SHA_DIGEST_WORDS];
2874 	static __u32 workspace[SHA_WORKSPACE_WORDS];
2875 
2876 	static union {
2877 		char __data[SHA_MESSAGE_BYTES];
2878 		struct {
2879 			struct in6_addr secret;
2880 			__be32 prefix[2];
2881 			unsigned char hwaddr[MAX_ADDR_LEN];
2882 			u8 dad_count;
2883 		} __packed;
2884 	} data;
2885 
2886 	struct in6_addr secret;
2887 	struct in6_addr temp;
2888 	struct net *net = dev_net(idev->dev);
2889 
2890 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
2891 
2892 	if (idev->cnf.stable_secret.initialized)
2893 		secret = idev->cnf.stable_secret.secret;
2894 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
2895 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
2896 	else
2897 		return -1;
2898 
2899 retry:
2900 	spin_lock_bh(&lock);
2901 
2902 	sha_init(digest);
2903 	memset(&data, 0, sizeof(data));
2904 	memset(workspace, 0, sizeof(workspace));
2905 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
2906 	data.prefix[0] = address->s6_addr32[0];
2907 	data.prefix[1] = address->s6_addr32[1];
2908 	data.secret = secret;
2909 	data.dad_count = dad_count;
2910 
2911 	sha_transform(digest, data.__data, workspace);
2912 
2913 	temp = *address;
2914 	temp.s6_addr32[2] = (__force __be32)digest[0];
2915 	temp.s6_addr32[3] = (__force __be32)digest[1];
2916 
2917 	spin_unlock_bh(&lock);
2918 
2919 	if (ipv6_reserved_interfaceid(temp)) {
2920 		dad_count++;
2921 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
2922 			return -1;
2923 		goto retry;
2924 	}
2925 
2926 	*address = temp;
2927 	return 0;
2928 }
2929 
2930 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
2931 {
2932 	struct in6_addr addr;
2933 
2934 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
2935 
2936 	if (idev->addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY) {
2937 		if (!ipv6_generate_stable_address(&addr, 0, idev))
2938 			addrconf_add_linklocal(idev, &addr,
2939 					       IFA_F_STABLE_PRIVACY);
2940 		else if (prefix_route)
2941 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
2942 	} else if (idev->addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64) {
2943 		/* addrconf_add_linklocal also adds a prefix_route and we
2944 		 * only need to care about prefix routes if ipv6_generate_eui64
2945 		 * couldn't generate one.
2946 		 */
2947 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
2948 			addrconf_add_linklocal(idev, &addr, 0);
2949 		else if (prefix_route)
2950 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
2951 	}
2952 }
2953 
2954 static void addrconf_dev_config(struct net_device *dev)
2955 {
2956 	struct inet6_dev *idev;
2957 
2958 	ASSERT_RTNL();
2959 
2960 	if ((dev->type != ARPHRD_ETHER) &&
2961 	    (dev->type != ARPHRD_FDDI) &&
2962 	    (dev->type != ARPHRD_ARCNET) &&
2963 	    (dev->type != ARPHRD_INFINIBAND) &&
2964 	    (dev->type != ARPHRD_IEEE802154) &&
2965 	    (dev->type != ARPHRD_IEEE1394) &&
2966 	    (dev->type != ARPHRD_TUNNEL6) &&
2967 	    (dev->type != ARPHRD_6LOWPAN)) {
2968 		/* Alas, we support only Ethernet autoconfiguration. */
2969 		return;
2970 	}
2971 
2972 	idev = addrconf_add_dev(dev);
2973 	if (IS_ERR(idev))
2974 		return;
2975 
2976 	addrconf_addr_gen(idev, false);
2977 }
2978 
2979 #if IS_ENABLED(CONFIG_IPV6_SIT)
2980 static void addrconf_sit_config(struct net_device *dev)
2981 {
2982 	struct inet6_dev *idev;
2983 
2984 	ASSERT_RTNL();
2985 
2986 	/*
2987 	 * Configure the tunnel with one of our IPv4
2988 	 * addresses... we should configure all of
2989 	 * our v4 addrs in the tunnel
2990 	 */
2991 
2992 	idev = ipv6_find_idev(dev);
2993 	if (!idev) {
2994 		pr_debug("%s: add_dev failed\n", __func__);
2995 		return;
2996 	}
2997 
2998 	if (dev->priv_flags & IFF_ISATAP) {
2999 		addrconf_addr_gen(idev, false);
3000 		return;
3001 	}
3002 
3003 	sit_add_v4_addrs(idev);
3004 
3005 	if (dev->flags&IFF_POINTOPOINT)
3006 		addrconf_add_mroute(dev);
3007 }
3008 #endif
3009 
3010 #if IS_ENABLED(CONFIG_NET_IPGRE)
3011 static void addrconf_gre_config(struct net_device *dev)
3012 {
3013 	struct inet6_dev *idev;
3014 
3015 	ASSERT_RTNL();
3016 
3017 	idev = ipv6_find_idev(dev);
3018 	if (!idev) {
3019 		pr_debug("%s: add_dev failed\n", __func__);
3020 		return;
3021 	}
3022 
3023 	addrconf_addr_gen(idev, true);
3024 }
3025 #endif
3026 
3027 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3028 			   void *ptr)
3029 {
3030 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3031 	struct inet6_dev *idev = __in6_dev_get(dev);
3032 	int run_pending = 0;
3033 	int err;
3034 
3035 	switch (event) {
3036 	case NETDEV_REGISTER:
3037 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3038 			idev = ipv6_add_dev(dev);
3039 			if (IS_ERR(idev))
3040 				return notifier_from_errno(PTR_ERR(idev));
3041 		}
3042 		break;
3043 
3044 	case NETDEV_UP:
3045 	case NETDEV_CHANGE:
3046 		if (dev->flags & IFF_SLAVE)
3047 			break;
3048 
3049 		if (idev && idev->cnf.disable_ipv6)
3050 			break;
3051 
3052 		if (event == NETDEV_UP) {
3053 			if (!addrconf_qdisc_ok(dev)) {
3054 				/* device is not ready yet. */
3055 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3056 					dev->name);
3057 				break;
3058 			}
3059 
3060 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3061 				idev = ipv6_add_dev(dev);
3062 
3063 			if (!IS_ERR_OR_NULL(idev)) {
3064 				idev->if_flags |= IF_READY;
3065 				run_pending = 1;
3066 			}
3067 		} else {
3068 			if (!addrconf_qdisc_ok(dev)) {
3069 				/* device is still not ready. */
3070 				break;
3071 			}
3072 
3073 			if (idev) {
3074 				if (idev->if_flags & IF_READY)
3075 					/* device is already configured. */
3076 					break;
3077 				idev->if_flags |= IF_READY;
3078 			}
3079 
3080 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3081 				dev->name);
3082 
3083 			run_pending = 1;
3084 		}
3085 
3086 		switch (dev->type) {
3087 #if IS_ENABLED(CONFIG_IPV6_SIT)
3088 		case ARPHRD_SIT:
3089 			addrconf_sit_config(dev);
3090 			break;
3091 #endif
3092 #if IS_ENABLED(CONFIG_NET_IPGRE)
3093 		case ARPHRD_IPGRE:
3094 			addrconf_gre_config(dev);
3095 			break;
3096 #endif
3097 		case ARPHRD_LOOPBACK:
3098 			init_loopback(dev);
3099 			break;
3100 
3101 		default:
3102 			addrconf_dev_config(dev);
3103 			break;
3104 		}
3105 
3106 		if (!IS_ERR_OR_NULL(idev)) {
3107 			if (run_pending)
3108 				addrconf_dad_run(idev);
3109 
3110 			/*
3111 			 * If the MTU changed during the interface down,
3112 			 * when the interface up, the changed MTU must be
3113 			 * reflected in the idev as well as routers.
3114 			 */
3115 			if (idev->cnf.mtu6 != dev->mtu &&
3116 			    dev->mtu >= IPV6_MIN_MTU) {
3117 				rt6_mtu_change(dev, dev->mtu);
3118 				idev->cnf.mtu6 = dev->mtu;
3119 			}
3120 			idev->tstamp = jiffies;
3121 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3122 
3123 			/*
3124 			 * If the changed mtu during down is lower than
3125 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3126 			 */
3127 			if (dev->mtu < IPV6_MIN_MTU)
3128 				addrconf_ifdown(dev, 1);
3129 		}
3130 		break;
3131 
3132 	case NETDEV_CHANGEMTU:
3133 		if (idev && dev->mtu >= IPV6_MIN_MTU) {
3134 			rt6_mtu_change(dev, dev->mtu);
3135 			idev->cnf.mtu6 = dev->mtu;
3136 			break;
3137 		}
3138 
3139 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3140 			idev = ipv6_add_dev(dev);
3141 			if (!IS_ERR(idev))
3142 				break;
3143 		}
3144 
3145 		/*
3146 		 * if MTU under IPV6_MIN_MTU.
3147 		 * Stop IPv6 on this interface.
3148 		 */
3149 
3150 	case NETDEV_DOWN:
3151 	case NETDEV_UNREGISTER:
3152 		/*
3153 		 *	Remove all addresses from this interface.
3154 		 */
3155 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3156 		break;
3157 
3158 	case NETDEV_CHANGENAME:
3159 		if (idev) {
3160 			snmp6_unregister_dev(idev);
3161 			addrconf_sysctl_unregister(idev);
3162 			err = addrconf_sysctl_register(idev);
3163 			if (err)
3164 				return notifier_from_errno(err);
3165 			err = snmp6_register_dev(idev);
3166 			if (err) {
3167 				addrconf_sysctl_unregister(idev);
3168 				return notifier_from_errno(err);
3169 			}
3170 		}
3171 		break;
3172 
3173 	case NETDEV_PRE_TYPE_CHANGE:
3174 	case NETDEV_POST_TYPE_CHANGE:
3175 		addrconf_type_change(dev, event);
3176 		break;
3177 	}
3178 
3179 	return NOTIFY_OK;
3180 }
3181 
3182 /*
3183  *	addrconf module should be notified of a device going up
3184  */
3185 static struct notifier_block ipv6_dev_notf = {
3186 	.notifier_call = addrconf_notify,
3187 };
3188 
3189 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3190 {
3191 	struct inet6_dev *idev;
3192 	ASSERT_RTNL();
3193 
3194 	idev = __in6_dev_get(dev);
3195 
3196 	if (event == NETDEV_POST_TYPE_CHANGE)
3197 		ipv6_mc_remap(idev);
3198 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3199 		ipv6_mc_unmap(idev);
3200 }
3201 
3202 static int addrconf_ifdown(struct net_device *dev, int how)
3203 {
3204 	struct net *net = dev_net(dev);
3205 	struct inet6_dev *idev;
3206 	struct inet6_ifaddr *ifa;
3207 	int state, i;
3208 
3209 	ASSERT_RTNL();
3210 
3211 	rt6_ifdown(net, dev);
3212 	neigh_ifdown(&nd_tbl, dev);
3213 
3214 	idev = __in6_dev_get(dev);
3215 	if (!idev)
3216 		return -ENODEV;
3217 
3218 	/*
3219 	 * Step 1: remove reference to ipv6 device from parent device.
3220 	 *	   Do not dev_put!
3221 	 */
3222 	if (how) {
3223 		idev->dead = 1;
3224 
3225 		/* protected by rtnl_lock */
3226 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3227 
3228 		/* Step 1.5: remove snmp6 entry */
3229 		snmp6_unregister_dev(idev);
3230 
3231 	}
3232 
3233 	/* Step 2: clear hash table */
3234 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3235 		struct hlist_head *h = &inet6_addr_lst[i];
3236 
3237 		spin_lock_bh(&addrconf_hash_lock);
3238 restart:
3239 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3240 			if (ifa->idev == idev) {
3241 				hlist_del_init_rcu(&ifa->addr_lst);
3242 				addrconf_del_dad_work(ifa);
3243 				goto restart;
3244 			}
3245 		}
3246 		spin_unlock_bh(&addrconf_hash_lock);
3247 	}
3248 
3249 	write_lock_bh(&idev->lock);
3250 
3251 	addrconf_del_rs_timer(idev);
3252 
3253 	/* Step 2: clear flags for stateless addrconf */
3254 	if (!how)
3255 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3256 
3257 	if (how && del_timer(&idev->regen_timer))
3258 		in6_dev_put(idev);
3259 
3260 	/* Step 3: clear tempaddr list */
3261 	while (!list_empty(&idev->tempaddr_list)) {
3262 		ifa = list_first_entry(&idev->tempaddr_list,
3263 				       struct inet6_ifaddr, tmp_list);
3264 		list_del(&ifa->tmp_list);
3265 		write_unlock_bh(&idev->lock);
3266 		spin_lock_bh(&ifa->lock);
3267 
3268 		if (ifa->ifpub) {
3269 			in6_ifa_put(ifa->ifpub);
3270 			ifa->ifpub = NULL;
3271 		}
3272 		spin_unlock_bh(&ifa->lock);
3273 		in6_ifa_put(ifa);
3274 		write_lock_bh(&idev->lock);
3275 	}
3276 
3277 	while (!list_empty(&idev->addr_list)) {
3278 		ifa = list_first_entry(&idev->addr_list,
3279 				       struct inet6_ifaddr, if_list);
3280 		addrconf_del_dad_work(ifa);
3281 
3282 		list_del(&ifa->if_list);
3283 
3284 		write_unlock_bh(&idev->lock);
3285 
3286 		spin_lock_bh(&ifa->lock);
3287 		state = ifa->state;
3288 		ifa->state = INET6_IFADDR_STATE_DEAD;
3289 		spin_unlock_bh(&ifa->lock);
3290 
3291 		if (state != INET6_IFADDR_STATE_DEAD) {
3292 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3293 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3294 		}
3295 		in6_ifa_put(ifa);
3296 
3297 		write_lock_bh(&idev->lock);
3298 	}
3299 
3300 	write_unlock_bh(&idev->lock);
3301 
3302 	/* Step 5: Discard anycast and multicast list */
3303 	if (how) {
3304 		ipv6_ac_destroy_dev(idev);
3305 		ipv6_mc_destroy_dev(idev);
3306 	} else {
3307 		ipv6_mc_down(idev);
3308 	}
3309 
3310 	idev->tstamp = jiffies;
3311 
3312 	/* Last: Shot the device (if unregistered) */
3313 	if (how) {
3314 		addrconf_sysctl_unregister(idev);
3315 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3316 		neigh_ifdown(&nd_tbl, dev);
3317 		in6_dev_put(idev);
3318 	}
3319 	return 0;
3320 }
3321 
3322 static void addrconf_rs_timer(unsigned long data)
3323 {
3324 	struct inet6_dev *idev = (struct inet6_dev *)data;
3325 	struct net_device *dev = idev->dev;
3326 	struct in6_addr lladdr;
3327 
3328 	write_lock(&idev->lock);
3329 	if (idev->dead || !(idev->if_flags & IF_READY))
3330 		goto out;
3331 
3332 	if (!ipv6_accept_ra(idev))
3333 		goto out;
3334 
3335 	/* Announcement received after solicitation was sent */
3336 	if (idev->if_flags & IF_RA_RCVD)
3337 		goto out;
3338 
3339 	if (idev->rs_probes++ < idev->cnf.rtr_solicits) {
3340 		write_unlock(&idev->lock);
3341 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3342 			ndisc_send_rs(dev, &lladdr,
3343 				      &in6addr_linklocal_allrouters);
3344 		else
3345 			goto put;
3346 
3347 		write_lock(&idev->lock);
3348 		/* The wait after the last probe can be shorter */
3349 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3350 					     idev->cnf.rtr_solicits) ?
3351 				      idev->cnf.rtr_solicit_delay :
3352 				      idev->cnf.rtr_solicit_interval);
3353 	} else {
3354 		/*
3355 		 * Note: we do not support deprecated "all on-link"
3356 		 * assumption any longer.
3357 		 */
3358 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3359 	}
3360 
3361 out:
3362 	write_unlock(&idev->lock);
3363 put:
3364 	in6_dev_put(idev);
3365 }
3366 
3367 /*
3368  *	Duplicate Address Detection
3369  */
3370 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3371 {
3372 	unsigned long rand_num;
3373 	struct inet6_dev *idev = ifp->idev;
3374 
3375 	if (ifp->flags & IFA_F_OPTIMISTIC)
3376 		rand_num = 0;
3377 	else
3378 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3379 
3380 	ifp->dad_probes = idev->cnf.dad_transmits;
3381 	addrconf_mod_dad_work(ifp, rand_num);
3382 }
3383 
3384 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3385 {
3386 	struct inet6_dev *idev = ifp->idev;
3387 	struct net_device *dev = idev->dev;
3388 
3389 	addrconf_join_solict(dev, &ifp->addr);
3390 
3391 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3392 
3393 	read_lock_bh(&idev->lock);
3394 	spin_lock(&ifp->lock);
3395 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3396 		goto out;
3397 
3398 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3399 	    idev->cnf.accept_dad < 1 ||
3400 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3401 	    ifp->flags & IFA_F_NODAD) {
3402 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3403 		spin_unlock(&ifp->lock);
3404 		read_unlock_bh(&idev->lock);
3405 
3406 		addrconf_dad_completed(ifp);
3407 		return;
3408 	}
3409 
3410 	if (!(idev->if_flags & IF_READY)) {
3411 		spin_unlock(&ifp->lock);
3412 		read_unlock_bh(&idev->lock);
3413 		/*
3414 		 * If the device is not ready:
3415 		 * - keep it tentative if it is a permanent address.
3416 		 * - otherwise, kill it.
3417 		 */
3418 		in6_ifa_hold(ifp);
3419 		addrconf_dad_stop(ifp, 0);
3420 		return;
3421 	}
3422 
3423 	/*
3424 	 * Optimistic nodes can start receiving
3425 	 * Frames right away
3426 	 */
3427 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3428 		ip6_ins_rt(ifp->rt);
3429 		if (ipv6_use_optimistic_addr(idev)) {
3430 			/* Because optimistic nodes can use this address,
3431 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3432 			 */
3433 			ipv6_ifa_notify(RTM_NEWADDR, ifp);
3434 		}
3435 	}
3436 
3437 	addrconf_dad_kick(ifp);
3438 out:
3439 	spin_unlock(&ifp->lock);
3440 	read_unlock_bh(&idev->lock);
3441 }
3442 
3443 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3444 {
3445 	bool begin_dad = false;
3446 
3447 	spin_lock_bh(&ifp->lock);
3448 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3449 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3450 		begin_dad = true;
3451 	}
3452 	spin_unlock_bh(&ifp->lock);
3453 
3454 	if (begin_dad)
3455 		addrconf_mod_dad_work(ifp, 0);
3456 }
3457 
3458 static void addrconf_dad_work(struct work_struct *w)
3459 {
3460 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3461 						struct inet6_ifaddr,
3462 						dad_work);
3463 	struct inet6_dev *idev = ifp->idev;
3464 	struct in6_addr mcaddr;
3465 
3466 	enum {
3467 		DAD_PROCESS,
3468 		DAD_BEGIN,
3469 		DAD_ABORT,
3470 	} action = DAD_PROCESS;
3471 
3472 	rtnl_lock();
3473 
3474 	spin_lock_bh(&ifp->lock);
3475 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3476 		action = DAD_BEGIN;
3477 		ifp->state = INET6_IFADDR_STATE_DAD;
3478 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3479 		action = DAD_ABORT;
3480 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
3481 	}
3482 	spin_unlock_bh(&ifp->lock);
3483 
3484 	if (action == DAD_BEGIN) {
3485 		addrconf_dad_begin(ifp);
3486 		goto out;
3487 	} else if (action == DAD_ABORT) {
3488 		addrconf_dad_stop(ifp, 1);
3489 		goto out;
3490 	}
3491 
3492 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
3493 		goto out;
3494 
3495 	write_lock_bh(&idev->lock);
3496 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3497 		write_unlock_bh(&idev->lock);
3498 		goto out;
3499 	}
3500 
3501 	spin_lock(&ifp->lock);
3502 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3503 		spin_unlock(&ifp->lock);
3504 		write_unlock_bh(&idev->lock);
3505 		goto out;
3506 	}
3507 
3508 	if (ifp->dad_probes == 0) {
3509 		/*
3510 		 * DAD was successful
3511 		 */
3512 
3513 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3514 		spin_unlock(&ifp->lock);
3515 		write_unlock_bh(&idev->lock);
3516 
3517 		addrconf_dad_completed(ifp);
3518 
3519 		goto out;
3520 	}
3521 
3522 	ifp->dad_probes--;
3523 	addrconf_mod_dad_work(ifp,
3524 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
3525 	spin_unlock(&ifp->lock);
3526 	write_unlock_bh(&idev->lock);
3527 
3528 	/* send a neighbour solicitation for our addr */
3529 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3530 	ndisc_send_ns(ifp->idev->dev, NULL, &ifp->addr, &mcaddr, &in6addr_any);
3531 out:
3532 	in6_ifa_put(ifp);
3533 	rtnl_unlock();
3534 }
3535 
3536 /* ifp->idev must be at least read locked */
3537 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
3538 {
3539 	struct inet6_ifaddr *ifpiter;
3540 	struct inet6_dev *idev = ifp->idev;
3541 
3542 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
3543 		if (ifpiter->scope > IFA_LINK)
3544 			break;
3545 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
3546 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
3547 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
3548 		    IFA_F_PERMANENT)
3549 			return false;
3550 	}
3551 	return true;
3552 }
3553 
3554 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
3555 {
3556 	struct net_device *dev = ifp->idev->dev;
3557 	struct in6_addr lladdr;
3558 	bool send_rs, send_mld;
3559 
3560 	addrconf_del_dad_work(ifp);
3561 
3562 	/*
3563 	 *	Configure the address for reception. Now it is valid.
3564 	 */
3565 
3566 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
3567 
3568 	/* If added prefix is link local and we are prepared to process
3569 	   router advertisements, start sending router solicitations.
3570 	 */
3571 
3572 	read_lock_bh(&ifp->idev->lock);
3573 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
3574 	send_rs = send_mld &&
3575 		  ipv6_accept_ra(ifp->idev) &&
3576 		  ifp->idev->cnf.rtr_solicits > 0 &&
3577 		  (dev->flags&IFF_LOOPBACK) == 0;
3578 	read_unlock_bh(&ifp->idev->lock);
3579 
3580 	/* While dad is in progress mld report's source address is in6_addrany.
3581 	 * Resend with proper ll now.
3582 	 */
3583 	if (send_mld)
3584 		ipv6_mc_dad_complete(ifp->idev);
3585 
3586 	if (send_rs) {
3587 		/*
3588 		 *	If a host as already performed a random delay
3589 		 *	[...] as part of DAD [...] there is no need
3590 		 *	to delay again before sending the first RS
3591 		 */
3592 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3593 			return;
3594 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
3595 
3596 		write_lock_bh(&ifp->idev->lock);
3597 		spin_lock(&ifp->lock);
3598 		ifp->idev->rs_probes = 1;
3599 		ifp->idev->if_flags |= IF_RS_SENT;
3600 		addrconf_mod_rs_timer(ifp->idev,
3601 				      ifp->idev->cnf.rtr_solicit_interval);
3602 		spin_unlock(&ifp->lock);
3603 		write_unlock_bh(&ifp->idev->lock);
3604 	}
3605 }
3606 
3607 static void addrconf_dad_run(struct inet6_dev *idev)
3608 {
3609 	struct inet6_ifaddr *ifp;
3610 
3611 	read_lock_bh(&idev->lock);
3612 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3613 		spin_lock(&ifp->lock);
3614 		if (ifp->flags & IFA_F_TENTATIVE &&
3615 		    ifp->state == INET6_IFADDR_STATE_DAD)
3616 			addrconf_dad_kick(ifp);
3617 		spin_unlock(&ifp->lock);
3618 	}
3619 	read_unlock_bh(&idev->lock);
3620 }
3621 
3622 #ifdef CONFIG_PROC_FS
3623 struct if6_iter_state {
3624 	struct seq_net_private p;
3625 	int bucket;
3626 	int offset;
3627 };
3628 
3629 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
3630 {
3631 	struct inet6_ifaddr *ifa = NULL;
3632 	struct if6_iter_state *state = seq->private;
3633 	struct net *net = seq_file_net(seq);
3634 	int p = 0;
3635 
3636 	/* initial bucket if pos is 0 */
3637 	if (pos == 0) {
3638 		state->bucket = 0;
3639 		state->offset = 0;
3640 	}
3641 
3642 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
3643 		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
3644 					 addr_lst) {
3645 			if (!net_eq(dev_net(ifa->idev->dev), net))
3646 				continue;
3647 			/* sync with offset */
3648 			if (p < state->offset) {
3649 				p++;
3650 				continue;
3651 			}
3652 			state->offset++;
3653 			return ifa;
3654 		}
3655 
3656 		/* prepare for next bucket */
3657 		state->offset = 0;
3658 		p = 0;
3659 	}
3660 	return NULL;
3661 }
3662 
3663 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
3664 					 struct inet6_ifaddr *ifa)
3665 {
3666 	struct if6_iter_state *state = seq->private;
3667 	struct net *net = seq_file_net(seq);
3668 
3669 	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
3670 		if (!net_eq(dev_net(ifa->idev->dev), net))
3671 			continue;
3672 		state->offset++;
3673 		return ifa;
3674 	}
3675 
3676 	while (++state->bucket < IN6_ADDR_HSIZE) {
3677 		state->offset = 0;
3678 		hlist_for_each_entry_rcu_bh(ifa,
3679 				     &inet6_addr_lst[state->bucket], addr_lst) {
3680 			if (!net_eq(dev_net(ifa->idev->dev), net))
3681 				continue;
3682 			state->offset++;
3683 			return ifa;
3684 		}
3685 	}
3686 
3687 	return NULL;
3688 }
3689 
3690 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
3691 	__acquires(rcu_bh)
3692 {
3693 	rcu_read_lock_bh();
3694 	return if6_get_first(seq, *pos);
3695 }
3696 
3697 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3698 {
3699 	struct inet6_ifaddr *ifa;
3700 
3701 	ifa = if6_get_next(seq, v);
3702 	++*pos;
3703 	return ifa;
3704 }
3705 
3706 static void if6_seq_stop(struct seq_file *seq, void *v)
3707 	__releases(rcu_bh)
3708 {
3709 	rcu_read_unlock_bh();
3710 }
3711 
3712 static int if6_seq_show(struct seq_file *seq, void *v)
3713 {
3714 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
3715 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
3716 		   &ifp->addr,
3717 		   ifp->idev->dev->ifindex,
3718 		   ifp->prefix_len,
3719 		   ifp->scope,
3720 		   (u8) ifp->flags,
3721 		   ifp->idev->dev->name);
3722 	return 0;
3723 }
3724 
3725 static const struct seq_operations if6_seq_ops = {
3726 	.start	= if6_seq_start,
3727 	.next	= if6_seq_next,
3728 	.show	= if6_seq_show,
3729 	.stop	= if6_seq_stop,
3730 };
3731 
3732 static int if6_seq_open(struct inode *inode, struct file *file)
3733 {
3734 	return seq_open_net(inode, file, &if6_seq_ops,
3735 			    sizeof(struct if6_iter_state));
3736 }
3737 
3738 static const struct file_operations if6_fops = {
3739 	.owner		= THIS_MODULE,
3740 	.open		= if6_seq_open,
3741 	.read		= seq_read,
3742 	.llseek		= seq_lseek,
3743 	.release	= seq_release_net,
3744 };
3745 
3746 static int __net_init if6_proc_net_init(struct net *net)
3747 {
3748 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
3749 		return -ENOMEM;
3750 	return 0;
3751 }
3752 
3753 static void __net_exit if6_proc_net_exit(struct net *net)
3754 {
3755 	remove_proc_entry("if_inet6", net->proc_net);
3756 }
3757 
3758 static struct pernet_operations if6_proc_net_ops = {
3759 	.init = if6_proc_net_init,
3760 	.exit = if6_proc_net_exit,
3761 };
3762 
3763 int __init if6_proc_init(void)
3764 {
3765 	return register_pernet_subsys(&if6_proc_net_ops);
3766 }
3767 
3768 void if6_proc_exit(void)
3769 {
3770 	unregister_pernet_subsys(&if6_proc_net_ops);
3771 }
3772 #endif	/* CONFIG_PROC_FS */
3773 
3774 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3775 /* Check if address is a home address configured on any interface. */
3776 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
3777 {
3778 	int ret = 0;
3779 	struct inet6_ifaddr *ifp = NULL;
3780 	unsigned int hash = inet6_addr_hash(addr);
3781 
3782 	rcu_read_lock_bh();
3783 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
3784 		if (!net_eq(dev_net(ifp->idev->dev), net))
3785 			continue;
3786 		if (ipv6_addr_equal(&ifp->addr, addr) &&
3787 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
3788 			ret = 1;
3789 			break;
3790 		}
3791 	}
3792 	rcu_read_unlock_bh();
3793 	return ret;
3794 }
3795 #endif
3796 
3797 /*
3798  *	Periodic address status verification
3799  */
3800 
3801 static void addrconf_verify_rtnl(void)
3802 {
3803 	unsigned long now, next, next_sec, next_sched;
3804 	struct inet6_ifaddr *ifp;
3805 	int i;
3806 
3807 	ASSERT_RTNL();
3808 
3809 	rcu_read_lock_bh();
3810 	now = jiffies;
3811 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
3812 
3813 	cancel_delayed_work(&addr_chk_work);
3814 
3815 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3816 restart:
3817 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
3818 			unsigned long age;
3819 
3820 			/* When setting preferred_lft to a value not zero or
3821 			 * infinity, while valid_lft is infinity
3822 			 * IFA_F_PERMANENT has a non-infinity life time.
3823 			 */
3824 			if ((ifp->flags & IFA_F_PERMANENT) &&
3825 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
3826 				continue;
3827 
3828 			spin_lock(&ifp->lock);
3829 			/* We try to batch several events at once. */
3830 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
3831 
3832 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
3833 			    age >= ifp->valid_lft) {
3834 				spin_unlock(&ifp->lock);
3835 				in6_ifa_hold(ifp);
3836 				ipv6_del_addr(ifp);
3837 				goto restart;
3838 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
3839 				spin_unlock(&ifp->lock);
3840 				continue;
3841 			} else if (age >= ifp->prefered_lft) {
3842 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
3843 				int deprecate = 0;
3844 
3845 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
3846 					deprecate = 1;
3847 					ifp->flags |= IFA_F_DEPRECATED;
3848 				}
3849 
3850 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
3851 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
3852 					next = ifp->tstamp + ifp->valid_lft * HZ;
3853 
3854 				spin_unlock(&ifp->lock);
3855 
3856 				if (deprecate) {
3857 					in6_ifa_hold(ifp);
3858 
3859 					ipv6_ifa_notify(0, ifp);
3860 					in6_ifa_put(ifp);
3861 					goto restart;
3862 				}
3863 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
3864 				   !(ifp->flags&IFA_F_TENTATIVE)) {
3865 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
3866 					ifp->idev->cnf.dad_transmits *
3867 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
3868 
3869 				if (age >= ifp->prefered_lft - regen_advance) {
3870 					struct inet6_ifaddr *ifpub = ifp->ifpub;
3871 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3872 						next = ifp->tstamp + ifp->prefered_lft * HZ;
3873 					if (!ifp->regen_count && ifpub) {
3874 						ifp->regen_count++;
3875 						in6_ifa_hold(ifp);
3876 						in6_ifa_hold(ifpub);
3877 						spin_unlock(&ifp->lock);
3878 
3879 						spin_lock(&ifpub->lock);
3880 						ifpub->regen_count = 0;
3881 						spin_unlock(&ifpub->lock);
3882 						ipv6_create_tempaddr(ifpub, ifp);
3883 						in6_ifa_put(ifpub);
3884 						in6_ifa_put(ifp);
3885 						goto restart;
3886 					}
3887 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
3888 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
3889 				spin_unlock(&ifp->lock);
3890 			} else {
3891 				/* ifp->prefered_lft <= ifp->valid_lft */
3892 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3893 					next = ifp->tstamp + ifp->prefered_lft * HZ;
3894 				spin_unlock(&ifp->lock);
3895 			}
3896 		}
3897 	}
3898 
3899 	next_sec = round_jiffies_up(next);
3900 	next_sched = next;
3901 
3902 	/* If rounded timeout is accurate enough, accept it. */
3903 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
3904 		next_sched = next_sec;
3905 
3906 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
3907 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
3908 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
3909 
3910 	ADBG(KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
3911 	      now, next, next_sec, next_sched);
3912 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
3913 	rcu_read_unlock_bh();
3914 }
3915 
3916 static void addrconf_verify_work(struct work_struct *w)
3917 {
3918 	rtnl_lock();
3919 	addrconf_verify_rtnl();
3920 	rtnl_unlock();
3921 }
3922 
3923 static void addrconf_verify(void)
3924 {
3925 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
3926 }
3927 
3928 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
3929 				     struct in6_addr **peer_pfx)
3930 {
3931 	struct in6_addr *pfx = NULL;
3932 
3933 	*peer_pfx = NULL;
3934 
3935 	if (addr)
3936 		pfx = nla_data(addr);
3937 
3938 	if (local) {
3939 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
3940 			*peer_pfx = pfx;
3941 		pfx = nla_data(local);
3942 	}
3943 
3944 	return pfx;
3945 }
3946 
3947 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
3948 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
3949 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
3950 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
3951 	[IFA_FLAGS]		= { .len = sizeof(u32) },
3952 };
3953 
3954 static int
3955 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
3956 {
3957 	struct net *net = sock_net(skb->sk);
3958 	struct ifaddrmsg *ifm;
3959 	struct nlattr *tb[IFA_MAX+1];
3960 	struct in6_addr *pfx, *peer_pfx;
3961 	u32 ifa_flags;
3962 	int err;
3963 
3964 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3965 	if (err < 0)
3966 		return err;
3967 
3968 	ifm = nlmsg_data(nlh);
3969 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
3970 	if (!pfx)
3971 		return -EINVAL;
3972 
3973 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
3974 
3975 	/* We ignore other flags so far. */
3976 	ifa_flags &= IFA_F_MANAGETEMPADDR;
3977 
3978 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
3979 			      ifm->ifa_prefixlen);
3980 }
3981 
3982 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags,
3983 			     u32 prefered_lft, u32 valid_lft)
3984 {
3985 	u32 flags;
3986 	clock_t expires;
3987 	unsigned long timeout;
3988 	bool was_managetempaddr;
3989 	bool had_prefixroute;
3990 
3991 	ASSERT_RTNL();
3992 
3993 	if (!valid_lft || (prefered_lft > valid_lft))
3994 		return -EINVAL;
3995 
3996 	if (ifa_flags & IFA_F_MANAGETEMPADDR &&
3997 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
3998 		return -EINVAL;
3999 
4000 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
4001 	if (addrconf_finite_timeout(timeout)) {
4002 		expires = jiffies_to_clock_t(timeout * HZ);
4003 		valid_lft = timeout;
4004 		flags = RTF_EXPIRES;
4005 	} else {
4006 		expires = 0;
4007 		flags = 0;
4008 		ifa_flags |= IFA_F_PERMANENT;
4009 	}
4010 
4011 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
4012 	if (addrconf_finite_timeout(timeout)) {
4013 		if (timeout == 0)
4014 			ifa_flags |= IFA_F_DEPRECATED;
4015 		prefered_lft = timeout;
4016 	}
4017 
4018 	spin_lock_bh(&ifp->lock);
4019 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4020 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4021 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4022 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4023 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4024 			IFA_F_NOPREFIXROUTE);
4025 	ifp->flags |= ifa_flags;
4026 	ifp->tstamp = jiffies;
4027 	ifp->valid_lft = valid_lft;
4028 	ifp->prefered_lft = prefered_lft;
4029 
4030 	spin_unlock_bh(&ifp->lock);
4031 	if (!(ifp->flags&IFA_F_TENTATIVE))
4032 		ipv6_ifa_notify(0, ifp);
4033 
4034 	if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
4035 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
4036 				      expires, flags);
4037 	} else if (had_prefixroute) {
4038 		enum cleanup_prefix_rt_t action;
4039 		unsigned long rt_expires;
4040 
4041 		write_lock_bh(&ifp->idev->lock);
4042 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4043 		write_unlock_bh(&ifp->idev->lock);
4044 
4045 		if (action != CLEANUP_PREFIX_RT_NOP) {
4046 			cleanup_prefix_route(ifp, rt_expires,
4047 				action == CLEANUP_PREFIX_RT_DEL);
4048 		}
4049 	}
4050 
4051 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4052 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
4053 			valid_lft = prefered_lft = 0;
4054 		manage_tempaddrs(ifp->idev, ifp, valid_lft, prefered_lft,
4055 				 !was_managetempaddr, jiffies);
4056 	}
4057 
4058 	addrconf_verify_rtnl();
4059 
4060 	return 0;
4061 }
4062 
4063 static int
4064 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
4065 {
4066 	struct net *net = sock_net(skb->sk);
4067 	struct ifaddrmsg *ifm;
4068 	struct nlattr *tb[IFA_MAX+1];
4069 	struct in6_addr *pfx, *peer_pfx;
4070 	struct inet6_ifaddr *ifa;
4071 	struct net_device *dev;
4072 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
4073 	u32 ifa_flags;
4074 	int err;
4075 
4076 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
4077 	if (err < 0)
4078 		return err;
4079 
4080 	ifm = nlmsg_data(nlh);
4081 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4082 	if (!pfx)
4083 		return -EINVAL;
4084 
4085 	if (tb[IFA_CACHEINFO]) {
4086 		struct ifa_cacheinfo *ci;
4087 
4088 		ci = nla_data(tb[IFA_CACHEINFO]);
4089 		valid_lft = ci->ifa_valid;
4090 		preferred_lft = ci->ifa_prefered;
4091 	} else {
4092 		preferred_lft = INFINITY_LIFE_TIME;
4093 		valid_lft = INFINITY_LIFE_TIME;
4094 	}
4095 
4096 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4097 	if (!dev)
4098 		return -ENODEV;
4099 
4100 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4101 
4102 	/* We ignore other flags so far. */
4103 	ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4104 		     IFA_F_NOPREFIXROUTE | IFA_F_MCAUTOJOIN;
4105 
4106 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
4107 	if (!ifa) {
4108 		/*
4109 		 * It would be best to check for !NLM_F_CREATE here but
4110 		 * userspace already relies on not having to provide this.
4111 		 */
4112 		return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,
4113 				      ifm->ifa_prefixlen, ifa_flags,
4114 				      preferred_lft, valid_lft);
4115 	}
4116 
4117 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4118 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4119 		err = -EEXIST;
4120 	else
4121 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
4122 
4123 	in6_ifa_put(ifa);
4124 
4125 	return err;
4126 }
4127 
4128 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4129 			  u8 scope, int ifindex)
4130 {
4131 	struct ifaddrmsg *ifm;
4132 
4133 	ifm = nlmsg_data(nlh);
4134 	ifm->ifa_family = AF_INET6;
4135 	ifm->ifa_prefixlen = prefixlen;
4136 	ifm->ifa_flags = flags;
4137 	ifm->ifa_scope = scope;
4138 	ifm->ifa_index = ifindex;
4139 }
4140 
4141 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4142 			 unsigned long tstamp, u32 preferred, u32 valid)
4143 {
4144 	struct ifa_cacheinfo ci;
4145 
4146 	ci.cstamp = cstamp_delta(cstamp);
4147 	ci.tstamp = cstamp_delta(tstamp);
4148 	ci.ifa_prefered = preferred;
4149 	ci.ifa_valid = valid;
4150 
4151 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4152 }
4153 
4154 static inline int rt_scope(int ifa_scope)
4155 {
4156 	if (ifa_scope & IFA_HOST)
4157 		return RT_SCOPE_HOST;
4158 	else if (ifa_scope & IFA_LINK)
4159 		return RT_SCOPE_LINK;
4160 	else if (ifa_scope & IFA_SITE)
4161 		return RT_SCOPE_SITE;
4162 	else
4163 		return RT_SCOPE_UNIVERSE;
4164 }
4165 
4166 static inline int inet6_ifaddr_msgsize(void)
4167 {
4168 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4169 	       + nla_total_size(16) /* IFA_LOCAL */
4170 	       + nla_total_size(16) /* IFA_ADDRESS */
4171 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4172 	       + nla_total_size(4)  /* IFA_FLAGS */;
4173 }
4174 
4175 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4176 			     u32 portid, u32 seq, int event, unsigned int flags)
4177 {
4178 	struct nlmsghdr  *nlh;
4179 	u32 preferred, valid;
4180 
4181 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4182 	if (!nlh)
4183 		return -EMSGSIZE;
4184 
4185 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4186 		      ifa->idev->dev->ifindex);
4187 
4188 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4189 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4190 		preferred = ifa->prefered_lft;
4191 		valid = ifa->valid_lft;
4192 		if (preferred != INFINITY_LIFE_TIME) {
4193 			long tval = (jiffies - ifa->tstamp)/HZ;
4194 			if (preferred > tval)
4195 				preferred -= tval;
4196 			else
4197 				preferred = 0;
4198 			if (valid != INFINITY_LIFE_TIME) {
4199 				if (valid > tval)
4200 					valid -= tval;
4201 				else
4202 					valid = 0;
4203 			}
4204 		}
4205 	} else {
4206 		preferred = INFINITY_LIFE_TIME;
4207 		valid = INFINITY_LIFE_TIME;
4208 	}
4209 
4210 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4211 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4212 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4213 			goto error;
4214 	} else
4215 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4216 			goto error;
4217 
4218 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4219 		goto error;
4220 
4221 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4222 		goto error;
4223 
4224 	nlmsg_end(skb, nlh);
4225 	return 0;
4226 
4227 error:
4228 	nlmsg_cancel(skb, nlh);
4229 	return -EMSGSIZE;
4230 }
4231 
4232 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4233 				u32 portid, u32 seq, int event, u16 flags)
4234 {
4235 	struct nlmsghdr  *nlh;
4236 	u8 scope = RT_SCOPE_UNIVERSE;
4237 	int ifindex = ifmca->idev->dev->ifindex;
4238 
4239 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4240 		scope = RT_SCOPE_SITE;
4241 
4242 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4243 	if (!nlh)
4244 		return -EMSGSIZE;
4245 
4246 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4247 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4248 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4249 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4250 		nlmsg_cancel(skb, nlh);
4251 		return -EMSGSIZE;
4252 	}
4253 
4254 	nlmsg_end(skb, nlh);
4255 	return 0;
4256 }
4257 
4258 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4259 				u32 portid, u32 seq, int event, unsigned int flags)
4260 {
4261 	struct nlmsghdr  *nlh;
4262 	u8 scope = RT_SCOPE_UNIVERSE;
4263 	int ifindex = ifaca->aca_idev->dev->ifindex;
4264 
4265 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4266 		scope = RT_SCOPE_SITE;
4267 
4268 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4269 	if (!nlh)
4270 		return -EMSGSIZE;
4271 
4272 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4273 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4274 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4275 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4276 		nlmsg_cancel(skb, nlh);
4277 		return -EMSGSIZE;
4278 	}
4279 
4280 	nlmsg_end(skb, nlh);
4281 	return 0;
4282 }
4283 
4284 enum addr_type_t {
4285 	UNICAST_ADDR,
4286 	MULTICAST_ADDR,
4287 	ANYCAST_ADDR,
4288 };
4289 
4290 /* called with rcu_read_lock() */
4291 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4292 			  struct netlink_callback *cb, enum addr_type_t type,
4293 			  int s_ip_idx, int *p_ip_idx)
4294 {
4295 	struct ifmcaddr6 *ifmca;
4296 	struct ifacaddr6 *ifaca;
4297 	int err = 1;
4298 	int ip_idx = *p_ip_idx;
4299 
4300 	read_lock_bh(&idev->lock);
4301 	switch (type) {
4302 	case UNICAST_ADDR: {
4303 		struct inet6_ifaddr *ifa;
4304 
4305 		/* unicast address incl. temp addr */
4306 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4307 			if (++ip_idx < s_ip_idx)
4308 				continue;
4309 			err = inet6_fill_ifaddr(skb, ifa,
4310 						NETLINK_CB(cb->skb).portid,
4311 						cb->nlh->nlmsg_seq,
4312 						RTM_NEWADDR,
4313 						NLM_F_MULTI);
4314 			if (err < 0)
4315 				break;
4316 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4317 		}
4318 		break;
4319 	}
4320 	case MULTICAST_ADDR:
4321 		/* multicast address */
4322 		for (ifmca = idev->mc_list; ifmca;
4323 		     ifmca = ifmca->next, ip_idx++) {
4324 			if (ip_idx < s_ip_idx)
4325 				continue;
4326 			err = inet6_fill_ifmcaddr(skb, ifmca,
4327 						  NETLINK_CB(cb->skb).portid,
4328 						  cb->nlh->nlmsg_seq,
4329 						  RTM_GETMULTICAST,
4330 						  NLM_F_MULTI);
4331 			if (err < 0)
4332 				break;
4333 		}
4334 		break;
4335 	case ANYCAST_ADDR:
4336 		/* anycast address */
4337 		for (ifaca = idev->ac_list; ifaca;
4338 		     ifaca = ifaca->aca_next, ip_idx++) {
4339 			if (ip_idx < s_ip_idx)
4340 				continue;
4341 			err = inet6_fill_ifacaddr(skb, ifaca,
4342 						  NETLINK_CB(cb->skb).portid,
4343 						  cb->nlh->nlmsg_seq,
4344 						  RTM_GETANYCAST,
4345 						  NLM_F_MULTI);
4346 			if (err < 0)
4347 				break;
4348 		}
4349 		break;
4350 	default:
4351 		break;
4352 	}
4353 	read_unlock_bh(&idev->lock);
4354 	*p_ip_idx = ip_idx;
4355 	return err;
4356 }
4357 
4358 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
4359 			   enum addr_type_t type)
4360 {
4361 	struct net *net = sock_net(skb->sk);
4362 	int h, s_h;
4363 	int idx, ip_idx;
4364 	int s_idx, s_ip_idx;
4365 	struct net_device *dev;
4366 	struct inet6_dev *idev;
4367 	struct hlist_head *head;
4368 
4369 	s_h = cb->args[0];
4370 	s_idx = idx = cb->args[1];
4371 	s_ip_idx = ip_idx = cb->args[2];
4372 
4373 	rcu_read_lock();
4374 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
4375 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4376 		idx = 0;
4377 		head = &net->dev_index_head[h];
4378 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4379 			if (idx < s_idx)
4380 				goto cont;
4381 			if (h > s_h || idx > s_idx)
4382 				s_ip_idx = 0;
4383 			ip_idx = 0;
4384 			idev = __in6_dev_get(dev);
4385 			if (!idev)
4386 				goto cont;
4387 
4388 			if (in6_dump_addrs(idev, skb, cb, type,
4389 					   s_ip_idx, &ip_idx) < 0)
4390 				goto done;
4391 cont:
4392 			idx++;
4393 		}
4394 	}
4395 done:
4396 	rcu_read_unlock();
4397 	cb->args[0] = h;
4398 	cb->args[1] = idx;
4399 	cb->args[2] = ip_idx;
4400 
4401 	return skb->len;
4402 }
4403 
4404 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
4405 {
4406 	enum addr_type_t type = UNICAST_ADDR;
4407 
4408 	return inet6_dump_addr(skb, cb, type);
4409 }
4410 
4411 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
4412 {
4413 	enum addr_type_t type = MULTICAST_ADDR;
4414 
4415 	return inet6_dump_addr(skb, cb, type);
4416 }
4417 
4418 
4419 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
4420 {
4421 	enum addr_type_t type = ANYCAST_ADDR;
4422 
4423 	return inet6_dump_addr(skb, cb, type);
4424 }
4425 
4426 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh)
4427 {
4428 	struct net *net = sock_net(in_skb->sk);
4429 	struct ifaddrmsg *ifm;
4430 	struct nlattr *tb[IFA_MAX+1];
4431 	struct in6_addr *addr = NULL, *peer;
4432 	struct net_device *dev = NULL;
4433 	struct inet6_ifaddr *ifa;
4434 	struct sk_buff *skb;
4435 	int err;
4436 
4437 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
4438 	if (err < 0)
4439 		goto errout;
4440 
4441 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
4442 	if (!addr) {
4443 		err = -EINVAL;
4444 		goto errout;
4445 	}
4446 
4447 	ifm = nlmsg_data(nlh);
4448 	if (ifm->ifa_index)
4449 		dev = __dev_get_by_index(net, ifm->ifa_index);
4450 
4451 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
4452 	if (!ifa) {
4453 		err = -EADDRNOTAVAIL;
4454 		goto errout;
4455 	}
4456 
4457 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
4458 	if (!skb) {
4459 		err = -ENOBUFS;
4460 		goto errout_ifa;
4461 	}
4462 
4463 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
4464 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
4465 	if (err < 0) {
4466 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4467 		WARN_ON(err == -EMSGSIZE);
4468 		kfree_skb(skb);
4469 		goto errout_ifa;
4470 	}
4471 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
4472 errout_ifa:
4473 	in6_ifa_put(ifa);
4474 errout:
4475 	return err;
4476 }
4477 
4478 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
4479 {
4480 	struct sk_buff *skb;
4481 	struct net *net = dev_net(ifa->idev->dev);
4482 	int err = -ENOBUFS;
4483 
4484 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
4485 	if (!skb)
4486 		goto errout;
4487 
4488 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
4489 	if (err < 0) {
4490 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4491 		WARN_ON(err == -EMSGSIZE);
4492 		kfree_skb(skb);
4493 		goto errout;
4494 	}
4495 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
4496 	return;
4497 errout:
4498 	if (err < 0)
4499 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
4500 }
4501 
4502 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
4503 				__s32 *array, int bytes)
4504 {
4505 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4506 
4507 	memset(array, 0, bytes);
4508 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4509 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4510 	array[DEVCONF_MTU6] = cnf->mtu6;
4511 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4512 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4513 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4514 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4515 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4516 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
4517 		jiffies_to_msecs(cnf->rtr_solicit_interval);
4518 	array[DEVCONF_RTR_SOLICIT_DELAY] =
4519 		jiffies_to_msecs(cnf->rtr_solicit_delay);
4520 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
4521 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
4522 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
4523 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
4524 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
4525 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
4526 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
4527 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
4528 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
4529 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
4530 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
4531 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
4532 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
4533 #ifdef CONFIG_IPV6_ROUTER_PREF
4534 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
4535 	array[DEVCONF_RTR_PROBE_INTERVAL] =
4536 		jiffies_to_msecs(cnf->rtr_probe_interval);
4537 #ifdef CONFIG_IPV6_ROUTE_INFO
4538 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
4539 #endif
4540 #endif
4541 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
4542 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
4543 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4544 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
4545 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
4546 #endif
4547 #ifdef CONFIG_IPV6_MROUTE
4548 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
4549 #endif
4550 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
4551 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
4552 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
4553 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
4554 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
4555 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
4556 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
4557 	/* we omit DEVCONF_STABLE_SECRET for now */
4558 }
4559 
4560 static inline size_t inet6_ifla6_size(void)
4561 {
4562 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
4563 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
4564 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
4565 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
4566 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
4567 	     + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */
4568 }
4569 
4570 static inline size_t inet6_if_nlmsg_size(void)
4571 {
4572 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
4573 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
4574 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
4575 	       + nla_total_size(4) /* IFLA_MTU */
4576 	       + nla_total_size(4) /* IFLA_LINK */
4577 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
4578 }
4579 
4580 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
4581 				      int items, int bytes)
4582 {
4583 	int i;
4584 	int pad = bytes - sizeof(u64) * items;
4585 	BUG_ON(pad < 0);
4586 
4587 	/* Use put_unaligned() because stats may not be aligned for u64. */
4588 	put_unaligned(items, &stats[0]);
4589 	for (i = 1; i < items; i++)
4590 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
4591 
4592 	memset(&stats[items], 0, pad);
4593 }
4594 
4595 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
4596 				      int items, int bytes, size_t syncpoff)
4597 {
4598 	int i;
4599 	int pad = bytes - sizeof(u64) * items;
4600 	BUG_ON(pad < 0);
4601 
4602 	/* Use put_unaligned() because stats may not be aligned for u64. */
4603 	put_unaligned(items, &stats[0]);
4604 	for (i = 1; i < items; i++)
4605 		put_unaligned(snmp_fold_field64(mib, i, syncpoff), &stats[i]);
4606 
4607 	memset(&stats[items], 0, pad);
4608 }
4609 
4610 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
4611 			     int bytes)
4612 {
4613 	switch (attrtype) {
4614 	case IFLA_INET6_STATS:
4615 		__snmp6_fill_stats64(stats, idev->stats.ipv6,
4616 				     IPSTATS_MIB_MAX, bytes, offsetof(struct ipstats_mib, syncp));
4617 		break;
4618 	case IFLA_INET6_ICMP6STATS:
4619 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, ICMP6_MIB_MAX, bytes);
4620 		break;
4621 	}
4622 }
4623 
4624 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev)
4625 {
4626 	struct nlattr *nla;
4627 	struct ifla_cacheinfo ci;
4628 
4629 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
4630 		goto nla_put_failure;
4631 	ci.max_reasm_len = IPV6_MAXPLEN;
4632 	ci.tstamp = cstamp_delta(idev->tstamp);
4633 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
4634 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
4635 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
4636 		goto nla_put_failure;
4637 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
4638 	if (!nla)
4639 		goto nla_put_failure;
4640 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
4641 
4642 	/* XXX - MC not implemented */
4643 
4644 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
4645 	if (!nla)
4646 		goto nla_put_failure;
4647 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
4648 
4649 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
4650 	if (!nla)
4651 		goto nla_put_failure;
4652 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
4653 
4654 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
4655 	if (!nla)
4656 		goto nla_put_failure;
4657 
4658 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->addr_gen_mode))
4659 		goto nla_put_failure;
4660 
4661 	read_lock_bh(&idev->lock);
4662 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
4663 	read_unlock_bh(&idev->lock);
4664 
4665 	return 0;
4666 
4667 nla_put_failure:
4668 	return -EMSGSIZE;
4669 }
4670 
4671 static size_t inet6_get_link_af_size(const struct net_device *dev)
4672 {
4673 	if (!__in6_dev_get(dev))
4674 		return 0;
4675 
4676 	return inet6_ifla6_size();
4677 }
4678 
4679 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
4680 {
4681 	struct inet6_dev *idev = __in6_dev_get(dev);
4682 
4683 	if (!idev)
4684 		return -ENODATA;
4685 
4686 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4687 		return -EMSGSIZE;
4688 
4689 	return 0;
4690 }
4691 
4692 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
4693 {
4694 	struct inet6_ifaddr *ifp;
4695 	struct net_device *dev = idev->dev;
4696 	bool update_rs = false;
4697 	struct in6_addr ll_addr;
4698 
4699 	ASSERT_RTNL();
4700 
4701 	if (!token)
4702 		return -EINVAL;
4703 	if (ipv6_addr_any(token))
4704 		return -EINVAL;
4705 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
4706 		return -EINVAL;
4707 	if (!ipv6_accept_ra(idev))
4708 		return -EINVAL;
4709 	if (idev->cnf.rtr_solicits <= 0)
4710 		return -EINVAL;
4711 
4712 	write_lock_bh(&idev->lock);
4713 
4714 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
4715 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
4716 
4717 	write_unlock_bh(&idev->lock);
4718 
4719 	if (!idev->dead && (idev->if_flags & IF_READY) &&
4720 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
4721 			     IFA_F_OPTIMISTIC)) {
4722 
4723 		/* If we're not ready, then normal ifup will take care
4724 		 * of this. Otherwise, we need to request our rs here.
4725 		 */
4726 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
4727 		update_rs = true;
4728 	}
4729 
4730 	write_lock_bh(&idev->lock);
4731 
4732 	if (update_rs) {
4733 		idev->if_flags |= IF_RS_SENT;
4734 		idev->rs_probes = 1;
4735 		addrconf_mod_rs_timer(idev, idev->cnf.rtr_solicit_interval);
4736 	}
4737 
4738 	/* Well, that's kinda nasty ... */
4739 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4740 		spin_lock(&ifp->lock);
4741 		if (ifp->tokenized) {
4742 			ifp->valid_lft = 0;
4743 			ifp->prefered_lft = 0;
4744 		}
4745 		spin_unlock(&ifp->lock);
4746 	}
4747 
4748 	write_unlock_bh(&idev->lock);
4749 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
4750 	addrconf_verify_rtnl();
4751 	return 0;
4752 }
4753 
4754 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
4755 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
4756 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
4757 };
4758 
4759 static int inet6_validate_link_af(const struct net_device *dev,
4760 				  const struct nlattr *nla)
4761 {
4762 	struct nlattr *tb[IFLA_INET6_MAX + 1];
4763 
4764 	if (dev && !__in6_dev_get(dev))
4765 		return -EAFNOSUPPORT;
4766 
4767 	return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy);
4768 }
4769 
4770 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
4771 {
4772 	int err = -EINVAL;
4773 	struct inet6_dev *idev = __in6_dev_get(dev);
4774 	struct nlattr *tb[IFLA_INET6_MAX + 1];
4775 
4776 	if (!idev)
4777 		return -EAFNOSUPPORT;
4778 
4779 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL) < 0)
4780 		BUG();
4781 
4782 	if (tb[IFLA_INET6_TOKEN]) {
4783 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
4784 		if (err)
4785 			return err;
4786 	}
4787 
4788 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
4789 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
4790 
4791 		if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
4792 		    mode != IN6_ADDR_GEN_MODE_NONE &&
4793 		    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY)
4794 			return -EINVAL;
4795 
4796 		if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
4797 		    !idev->cnf.stable_secret.initialized &&
4798 		    !dev_net(dev)->ipv6.devconf_dflt->stable_secret.initialized)
4799 			return -EINVAL;
4800 
4801 		idev->addr_gen_mode = mode;
4802 		err = 0;
4803 	}
4804 
4805 	return err;
4806 }
4807 
4808 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
4809 			     u32 portid, u32 seq, int event, unsigned int flags)
4810 {
4811 	struct net_device *dev = idev->dev;
4812 	struct ifinfomsg *hdr;
4813 	struct nlmsghdr *nlh;
4814 	void *protoinfo;
4815 
4816 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
4817 	if (!nlh)
4818 		return -EMSGSIZE;
4819 
4820 	hdr = nlmsg_data(nlh);
4821 	hdr->ifi_family = AF_INET6;
4822 	hdr->__ifi_pad = 0;
4823 	hdr->ifi_type = dev->type;
4824 	hdr->ifi_index = dev->ifindex;
4825 	hdr->ifi_flags = dev_get_flags(dev);
4826 	hdr->ifi_change = 0;
4827 
4828 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
4829 	    (dev->addr_len &&
4830 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
4831 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
4832 	    (dev->ifindex != dev_get_iflink(dev) &&
4833 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))))
4834 		goto nla_put_failure;
4835 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
4836 	if (!protoinfo)
4837 		goto nla_put_failure;
4838 
4839 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4840 		goto nla_put_failure;
4841 
4842 	nla_nest_end(skb, protoinfo);
4843 	nlmsg_end(skb, nlh);
4844 	return 0;
4845 
4846 nla_put_failure:
4847 	nlmsg_cancel(skb, nlh);
4848 	return -EMSGSIZE;
4849 }
4850 
4851 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
4852 {
4853 	struct net *net = sock_net(skb->sk);
4854 	int h, s_h;
4855 	int idx = 0, s_idx;
4856 	struct net_device *dev;
4857 	struct inet6_dev *idev;
4858 	struct hlist_head *head;
4859 
4860 	s_h = cb->args[0];
4861 	s_idx = cb->args[1];
4862 
4863 	rcu_read_lock();
4864 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4865 		idx = 0;
4866 		head = &net->dev_index_head[h];
4867 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4868 			if (idx < s_idx)
4869 				goto cont;
4870 			idev = __in6_dev_get(dev);
4871 			if (!idev)
4872 				goto cont;
4873 			if (inet6_fill_ifinfo(skb, idev,
4874 					      NETLINK_CB(cb->skb).portid,
4875 					      cb->nlh->nlmsg_seq,
4876 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
4877 				goto out;
4878 cont:
4879 			idx++;
4880 		}
4881 	}
4882 out:
4883 	rcu_read_unlock();
4884 	cb->args[1] = idx;
4885 	cb->args[0] = h;
4886 
4887 	return skb->len;
4888 }
4889 
4890 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
4891 {
4892 	struct sk_buff *skb;
4893 	struct net *net = dev_net(idev->dev);
4894 	int err = -ENOBUFS;
4895 
4896 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
4897 	if (!skb)
4898 		goto errout;
4899 
4900 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
4901 	if (err < 0) {
4902 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
4903 		WARN_ON(err == -EMSGSIZE);
4904 		kfree_skb(skb);
4905 		goto errout;
4906 	}
4907 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
4908 	return;
4909 errout:
4910 	if (err < 0)
4911 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
4912 }
4913 
4914 static inline size_t inet6_prefix_nlmsg_size(void)
4915 {
4916 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
4917 	       + nla_total_size(sizeof(struct in6_addr))
4918 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
4919 }
4920 
4921 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
4922 			     struct prefix_info *pinfo, u32 portid, u32 seq,
4923 			     int event, unsigned int flags)
4924 {
4925 	struct prefixmsg *pmsg;
4926 	struct nlmsghdr *nlh;
4927 	struct prefix_cacheinfo	ci;
4928 
4929 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
4930 	if (!nlh)
4931 		return -EMSGSIZE;
4932 
4933 	pmsg = nlmsg_data(nlh);
4934 	pmsg->prefix_family = AF_INET6;
4935 	pmsg->prefix_pad1 = 0;
4936 	pmsg->prefix_pad2 = 0;
4937 	pmsg->prefix_ifindex = idev->dev->ifindex;
4938 	pmsg->prefix_len = pinfo->prefix_len;
4939 	pmsg->prefix_type = pinfo->type;
4940 	pmsg->prefix_pad3 = 0;
4941 	pmsg->prefix_flags = 0;
4942 	if (pinfo->onlink)
4943 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
4944 	if (pinfo->autoconf)
4945 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
4946 
4947 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
4948 		goto nla_put_failure;
4949 	ci.preferred_time = ntohl(pinfo->prefered);
4950 	ci.valid_time = ntohl(pinfo->valid);
4951 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
4952 		goto nla_put_failure;
4953 	nlmsg_end(skb, nlh);
4954 	return 0;
4955 
4956 nla_put_failure:
4957 	nlmsg_cancel(skb, nlh);
4958 	return -EMSGSIZE;
4959 }
4960 
4961 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
4962 			 struct prefix_info *pinfo)
4963 {
4964 	struct sk_buff *skb;
4965 	struct net *net = dev_net(idev->dev);
4966 	int err = -ENOBUFS;
4967 
4968 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
4969 	if (!skb)
4970 		goto errout;
4971 
4972 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
4973 	if (err < 0) {
4974 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
4975 		WARN_ON(err == -EMSGSIZE);
4976 		kfree_skb(skb);
4977 		goto errout;
4978 	}
4979 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
4980 	return;
4981 errout:
4982 	if (err < 0)
4983 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
4984 }
4985 
4986 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4987 {
4988 	struct net *net = dev_net(ifp->idev->dev);
4989 
4990 	if (event)
4991 		ASSERT_RTNL();
4992 
4993 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
4994 
4995 	switch (event) {
4996 	case RTM_NEWADDR:
4997 		/*
4998 		 * If the address was optimistic
4999 		 * we inserted the route at the start of
5000 		 * our DAD process, so we don't need
5001 		 * to do it again
5002 		 */
5003 		if (!(ifp->rt->rt6i_node))
5004 			ip6_ins_rt(ifp->rt);
5005 		if (ifp->idev->cnf.forwarding)
5006 			addrconf_join_anycast(ifp);
5007 		if (!ipv6_addr_any(&ifp->peer_addr))
5008 			addrconf_prefix_route(&ifp->peer_addr, 128,
5009 					      ifp->idev->dev, 0, 0);
5010 		break;
5011 	case RTM_DELADDR:
5012 		if (ifp->idev->cnf.forwarding)
5013 			addrconf_leave_anycast(ifp);
5014 		addrconf_leave_solict(ifp->idev, &ifp->addr);
5015 		if (!ipv6_addr_any(&ifp->peer_addr)) {
5016 			struct rt6_info *rt;
5017 
5018 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5019 						       ifp->idev->dev, 0, 0);
5020 			if (rt && ip6_del_rt(rt))
5021 				dst_free(&rt->dst);
5022 		}
5023 		dst_hold(&ifp->rt->dst);
5024 
5025 		if (ip6_del_rt(ifp->rt))
5026 			dst_free(&ifp->rt->dst);
5027 
5028 		rt_genid_bump_ipv6(net);
5029 		break;
5030 	}
5031 	atomic_inc(&net->ipv6.dev_addr_genid);
5032 }
5033 
5034 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5035 {
5036 	rcu_read_lock_bh();
5037 	if (likely(ifp->idev->dead == 0))
5038 		__ipv6_ifa_notify(event, ifp);
5039 	rcu_read_unlock_bh();
5040 }
5041 
5042 #ifdef CONFIG_SYSCTL
5043 
5044 static
5045 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
5046 			   void __user *buffer, size_t *lenp, loff_t *ppos)
5047 {
5048 	int *valp = ctl->data;
5049 	int val = *valp;
5050 	loff_t pos = *ppos;
5051 	struct ctl_table lctl;
5052 	int ret;
5053 
5054 	/*
5055 	 * ctl->data points to idev->cnf.forwarding, we should
5056 	 * not modify it until we get the rtnl lock.
5057 	 */
5058 	lctl = *ctl;
5059 	lctl.data = &val;
5060 
5061 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5062 
5063 	if (write)
5064 		ret = addrconf_fixup_forwarding(ctl, valp, val);
5065 	if (ret)
5066 		*ppos = pos;
5067 	return ret;
5068 }
5069 
5070 static
5071 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
5072 			void __user *buffer, size_t *lenp, loff_t *ppos)
5073 {
5074 	struct inet6_dev *idev = ctl->extra1;
5075 	int min_mtu = IPV6_MIN_MTU;
5076 	struct ctl_table lctl;
5077 
5078 	lctl = *ctl;
5079 	lctl.extra1 = &min_mtu;
5080 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
5081 
5082 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
5083 }
5084 
5085 static void dev_disable_change(struct inet6_dev *idev)
5086 {
5087 	struct netdev_notifier_info info;
5088 
5089 	if (!idev || !idev->dev)
5090 		return;
5091 
5092 	netdev_notifier_info_init(&info, idev->dev);
5093 	if (idev->cnf.disable_ipv6)
5094 		addrconf_notify(NULL, NETDEV_DOWN, &info);
5095 	else
5096 		addrconf_notify(NULL, NETDEV_UP, &info);
5097 }
5098 
5099 static void addrconf_disable_change(struct net *net, __s32 newf)
5100 {
5101 	struct net_device *dev;
5102 	struct inet6_dev *idev;
5103 
5104 	rcu_read_lock();
5105 	for_each_netdev_rcu(net, dev) {
5106 		idev = __in6_dev_get(dev);
5107 		if (idev) {
5108 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
5109 			idev->cnf.disable_ipv6 = newf;
5110 			if (changed)
5111 				dev_disable_change(idev);
5112 		}
5113 	}
5114 	rcu_read_unlock();
5115 }
5116 
5117 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
5118 {
5119 	struct net *net;
5120 	int old;
5121 
5122 	if (!rtnl_trylock())
5123 		return restart_syscall();
5124 
5125 	net = (struct net *)table->extra2;
5126 	old = *p;
5127 	*p = newf;
5128 
5129 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
5130 		rtnl_unlock();
5131 		return 0;
5132 	}
5133 
5134 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
5135 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
5136 		addrconf_disable_change(net, newf);
5137 	} else if ((!newf) ^ (!old))
5138 		dev_disable_change((struct inet6_dev *)table->extra1);
5139 
5140 	rtnl_unlock();
5141 	return 0;
5142 }
5143 
5144 static
5145 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
5146 			    void __user *buffer, size_t *lenp, loff_t *ppos)
5147 {
5148 	int *valp = ctl->data;
5149 	int val = *valp;
5150 	loff_t pos = *ppos;
5151 	struct ctl_table lctl;
5152 	int ret;
5153 
5154 	/*
5155 	 * ctl->data points to idev->cnf.disable_ipv6, we should
5156 	 * not modify it until we get the rtnl lock.
5157 	 */
5158 	lctl = *ctl;
5159 	lctl.data = &val;
5160 
5161 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5162 
5163 	if (write)
5164 		ret = addrconf_disable_ipv6(ctl, valp, val);
5165 	if (ret)
5166 		*ppos = pos;
5167 	return ret;
5168 }
5169 
5170 static
5171 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
5172 			      void __user *buffer, size_t *lenp, loff_t *ppos)
5173 {
5174 	int *valp = ctl->data;
5175 	int ret;
5176 	int old, new;
5177 
5178 	old = *valp;
5179 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5180 	new = *valp;
5181 
5182 	if (write && old != new) {
5183 		struct net *net = ctl->extra2;
5184 
5185 		if (!rtnl_trylock())
5186 			return restart_syscall();
5187 
5188 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
5189 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
5190 						     NETCONFA_IFINDEX_DEFAULT,
5191 						     net->ipv6.devconf_dflt);
5192 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
5193 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
5194 						     NETCONFA_IFINDEX_ALL,
5195 						     net->ipv6.devconf_all);
5196 		else {
5197 			struct inet6_dev *idev = ctl->extra1;
5198 
5199 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
5200 						     idev->dev->ifindex,
5201 						     &idev->cnf);
5202 		}
5203 		rtnl_unlock();
5204 	}
5205 
5206 	return ret;
5207 }
5208 
5209 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
5210 					 void __user *buffer, size_t *lenp,
5211 					 loff_t *ppos)
5212 {
5213 	int err;
5214 	struct in6_addr addr;
5215 	char str[IPV6_MAX_STRLEN];
5216 	struct ctl_table lctl = *ctl;
5217 	struct net *net = ctl->extra2;
5218 	struct ipv6_stable_secret *secret = ctl->data;
5219 
5220 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
5221 		return -EIO;
5222 
5223 	lctl.maxlen = IPV6_MAX_STRLEN;
5224 	lctl.data = str;
5225 
5226 	if (!rtnl_trylock())
5227 		return restart_syscall();
5228 
5229 	if (!write && !secret->initialized) {
5230 		err = -EIO;
5231 		goto out;
5232 	}
5233 
5234 	if (!write) {
5235 		err = snprintf(str, sizeof(str), "%pI6",
5236 			       &secret->secret);
5237 		if (err >= sizeof(str)) {
5238 			err = -EIO;
5239 			goto out;
5240 		}
5241 	}
5242 
5243 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
5244 	if (err || !write)
5245 		goto out;
5246 
5247 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
5248 		err = -EIO;
5249 		goto out;
5250 	}
5251 
5252 	secret->initialized = true;
5253 	secret->secret = addr;
5254 
5255 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
5256 		struct net_device *dev;
5257 
5258 		for_each_netdev(net, dev) {
5259 			struct inet6_dev *idev = __in6_dev_get(dev);
5260 
5261 			if (idev) {
5262 				idev->addr_gen_mode =
5263 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5264 			}
5265 		}
5266 	} else {
5267 		struct inet6_dev *idev = ctl->extra1;
5268 
5269 		idev->addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5270 	}
5271 
5272 out:
5273 	rtnl_unlock();
5274 
5275 	return err;
5276 }
5277 
5278 static struct addrconf_sysctl_table
5279 {
5280 	struct ctl_table_header *sysctl_header;
5281 	struct ctl_table addrconf_vars[DEVCONF_MAX+1];
5282 } addrconf_sysctl __read_mostly = {
5283 	.sysctl_header = NULL,
5284 	.addrconf_vars = {
5285 		{
5286 			.procname	= "forwarding",
5287 			.data		= &ipv6_devconf.forwarding,
5288 			.maxlen		= sizeof(int),
5289 			.mode		= 0644,
5290 			.proc_handler	= addrconf_sysctl_forward,
5291 		},
5292 		{
5293 			.procname	= "hop_limit",
5294 			.data		= &ipv6_devconf.hop_limit,
5295 			.maxlen		= sizeof(int),
5296 			.mode		= 0644,
5297 			.proc_handler	= proc_dointvec,
5298 		},
5299 		{
5300 			.procname	= "mtu",
5301 			.data		= &ipv6_devconf.mtu6,
5302 			.maxlen		= sizeof(int),
5303 			.mode		= 0644,
5304 			.proc_handler	= addrconf_sysctl_mtu,
5305 		},
5306 		{
5307 			.procname	= "accept_ra",
5308 			.data		= &ipv6_devconf.accept_ra,
5309 			.maxlen		= sizeof(int),
5310 			.mode		= 0644,
5311 			.proc_handler	= proc_dointvec,
5312 		},
5313 		{
5314 			.procname	= "accept_redirects",
5315 			.data		= &ipv6_devconf.accept_redirects,
5316 			.maxlen		= sizeof(int),
5317 			.mode		= 0644,
5318 			.proc_handler	= proc_dointvec,
5319 		},
5320 		{
5321 			.procname	= "autoconf",
5322 			.data		= &ipv6_devconf.autoconf,
5323 			.maxlen		= sizeof(int),
5324 			.mode		= 0644,
5325 			.proc_handler	= proc_dointvec,
5326 		},
5327 		{
5328 			.procname	= "dad_transmits",
5329 			.data		= &ipv6_devconf.dad_transmits,
5330 			.maxlen		= sizeof(int),
5331 			.mode		= 0644,
5332 			.proc_handler	= proc_dointvec,
5333 		},
5334 		{
5335 			.procname	= "router_solicitations",
5336 			.data		= &ipv6_devconf.rtr_solicits,
5337 			.maxlen		= sizeof(int),
5338 			.mode		= 0644,
5339 			.proc_handler	= proc_dointvec,
5340 		},
5341 		{
5342 			.procname	= "router_solicitation_interval",
5343 			.data		= &ipv6_devconf.rtr_solicit_interval,
5344 			.maxlen		= sizeof(int),
5345 			.mode		= 0644,
5346 			.proc_handler	= proc_dointvec_jiffies,
5347 		},
5348 		{
5349 			.procname	= "router_solicitation_delay",
5350 			.data		= &ipv6_devconf.rtr_solicit_delay,
5351 			.maxlen		= sizeof(int),
5352 			.mode		= 0644,
5353 			.proc_handler	= proc_dointvec_jiffies,
5354 		},
5355 		{
5356 			.procname	= "force_mld_version",
5357 			.data		= &ipv6_devconf.force_mld_version,
5358 			.maxlen		= sizeof(int),
5359 			.mode		= 0644,
5360 			.proc_handler	= proc_dointvec,
5361 		},
5362 		{
5363 			.procname	= "mldv1_unsolicited_report_interval",
5364 			.data		=
5365 				&ipv6_devconf.mldv1_unsolicited_report_interval,
5366 			.maxlen		= sizeof(int),
5367 			.mode		= 0644,
5368 			.proc_handler	= proc_dointvec_ms_jiffies,
5369 		},
5370 		{
5371 			.procname	= "mldv2_unsolicited_report_interval",
5372 			.data		=
5373 				&ipv6_devconf.mldv2_unsolicited_report_interval,
5374 			.maxlen		= sizeof(int),
5375 			.mode		= 0644,
5376 			.proc_handler	= proc_dointvec_ms_jiffies,
5377 		},
5378 		{
5379 			.procname	= "use_tempaddr",
5380 			.data		= &ipv6_devconf.use_tempaddr,
5381 			.maxlen		= sizeof(int),
5382 			.mode		= 0644,
5383 			.proc_handler	= proc_dointvec,
5384 		},
5385 		{
5386 			.procname	= "temp_valid_lft",
5387 			.data		= &ipv6_devconf.temp_valid_lft,
5388 			.maxlen		= sizeof(int),
5389 			.mode		= 0644,
5390 			.proc_handler	= proc_dointvec,
5391 		},
5392 		{
5393 			.procname	= "temp_prefered_lft",
5394 			.data		= &ipv6_devconf.temp_prefered_lft,
5395 			.maxlen		= sizeof(int),
5396 			.mode		= 0644,
5397 			.proc_handler	= proc_dointvec,
5398 		},
5399 		{
5400 			.procname	= "regen_max_retry",
5401 			.data		= &ipv6_devconf.regen_max_retry,
5402 			.maxlen		= sizeof(int),
5403 			.mode		= 0644,
5404 			.proc_handler	= proc_dointvec,
5405 		},
5406 		{
5407 			.procname	= "max_desync_factor",
5408 			.data		= &ipv6_devconf.max_desync_factor,
5409 			.maxlen		= sizeof(int),
5410 			.mode		= 0644,
5411 			.proc_handler	= proc_dointvec,
5412 		},
5413 		{
5414 			.procname	= "max_addresses",
5415 			.data		= &ipv6_devconf.max_addresses,
5416 			.maxlen		= sizeof(int),
5417 			.mode		= 0644,
5418 			.proc_handler	= proc_dointvec,
5419 		},
5420 		{
5421 			.procname	= "accept_ra_defrtr",
5422 			.data		= &ipv6_devconf.accept_ra_defrtr,
5423 			.maxlen		= sizeof(int),
5424 			.mode		= 0644,
5425 			.proc_handler	= proc_dointvec,
5426 		},
5427 		{
5428 			.procname	= "accept_ra_pinfo",
5429 			.data		= &ipv6_devconf.accept_ra_pinfo,
5430 			.maxlen		= sizeof(int),
5431 			.mode		= 0644,
5432 			.proc_handler	= proc_dointvec,
5433 		},
5434 #ifdef CONFIG_IPV6_ROUTER_PREF
5435 		{
5436 			.procname	= "accept_ra_rtr_pref",
5437 			.data		= &ipv6_devconf.accept_ra_rtr_pref,
5438 			.maxlen		= sizeof(int),
5439 			.mode		= 0644,
5440 			.proc_handler	= proc_dointvec,
5441 		},
5442 		{
5443 			.procname	= "router_probe_interval",
5444 			.data		= &ipv6_devconf.rtr_probe_interval,
5445 			.maxlen		= sizeof(int),
5446 			.mode		= 0644,
5447 			.proc_handler	= proc_dointvec_jiffies,
5448 		},
5449 #ifdef CONFIG_IPV6_ROUTE_INFO
5450 		{
5451 			.procname	= "accept_ra_rt_info_max_plen",
5452 			.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
5453 			.maxlen		= sizeof(int),
5454 			.mode		= 0644,
5455 			.proc_handler	= proc_dointvec,
5456 		},
5457 #endif
5458 #endif
5459 		{
5460 			.procname	= "proxy_ndp",
5461 			.data		= &ipv6_devconf.proxy_ndp,
5462 			.maxlen		= sizeof(int),
5463 			.mode		= 0644,
5464 			.proc_handler	= addrconf_sysctl_proxy_ndp,
5465 		},
5466 		{
5467 			.procname	= "accept_source_route",
5468 			.data		= &ipv6_devconf.accept_source_route,
5469 			.maxlen		= sizeof(int),
5470 			.mode		= 0644,
5471 			.proc_handler	= proc_dointvec,
5472 		},
5473 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5474 		{
5475 			.procname       = "optimistic_dad",
5476 			.data           = &ipv6_devconf.optimistic_dad,
5477 			.maxlen         = sizeof(int),
5478 			.mode           = 0644,
5479 			.proc_handler   = proc_dointvec,
5480 
5481 		},
5482 		{
5483 			.procname       = "use_optimistic",
5484 			.data           = &ipv6_devconf.use_optimistic,
5485 			.maxlen         = sizeof(int),
5486 			.mode           = 0644,
5487 			.proc_handler   = proc_dointvec,
5488 
5489 		},
5490 #endif
5491 #ifdef CONFIG_IPV6_MROUTE
5492 		{
5493 			.procname	= "mc_forwarding",
5494 			.data		= &ipv6_devconf.mc_forwarding,
5495 			.maxlen		= sizeof(int),
5496 			.mode		= 0444,
5497 			.proc_handler	= proc_dointvec,
5498 		},
5499 #endif
5500 		{
5501 			.procname	= "disable_ipv6",
5502 			.data		= &ipv6_devconf.disable_ipv6,
5503 			.maxlen		= sizeof(int),
5504 			.mode		= 0644,
5505 			.proc_handler	= addrconf_sysctl_disable,
5506 		},
5507 		{
5508 			.procname	= "accept_dad",
5509 			.data		= &ipv6_devconf.accept_dad,
5510 			.maxlen		= sizeof(int),
5511 			.mode		= 0644,
5512 			.proc_handler	= proc_dointvec,
5513 		},
5514 		{
5515 			.procname       = "force_tllao",
5516 			.data           = &ipv6_devconf.force_tllao,
5517 			.maxlen         = sizeof(int),
5518 			.mode           = 0644,
5519 			.proc_handler   = proc_dointvec
5520 		},
5521 		{
5522 			.procname       = "ndisc_notify",
5523 			.data           = &ipv6_devconf.ndisc_notify,
5524 			.maxlen         = sizeof(int),
5525 			.mode           = 0644,
5526 			.proc_handler   = proc_dointvec
5527 		},
5528 		{
5529 			.procname	= "suppress_frag_ndisc",
5530 			.data		= &ipv6_devconf.suppress_frag_ndisc,
5531 			.maxlen		= sizeof(int),
5532 			.mode		= 0644,
5533 			.proc_handler	= proc_dointvec
5534 		},
5535 		{
5536 			.procname	= "accept_ra_from_local",
5537 			.data		= &ipv6_devconf.accept_ra_from_local,
5538 			.maxlen		= sizeof(int),
5539 			.mode		= 0644,
5540 			.proc_handler	= proc_dointvec,
5541 		},
5542 		{
5543 			.procname	= "accept_ra_mtu",
5544 			.data		= &ipv6_devconf.accept_ra_mtu,
5545 			.maxlen		= sizeof(int),
5546 			.mode		= 0644,
5547 			.proc_handler	= proc_dointvec,
5548 		},
5549 		{
5550 			.procname	= "stable_secret",
5551 			.data		= &ipv6_devconf.stable_secret,
5552 			.maxlen		= IPV6_MAX_STRLEN,
5553 			.mode		= 0600,
5554 			.proc_handler	= addrconf_sysctl_stable_secret,
5555 		},
5556 		{
5557 			/* sentinel */
5558 		}
5559 	},
5560 };
5561 
5562 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
5563 		struct inet6_dev *idev, struct ipv6_devconf *p)
5564 {
5565 	int i;
5566 	struct addrconf_sysctl_table *t;
5567 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
5568 
5569 	t = kmemdup(&addrconf_sysctl, sizeof(*t), GFP_KERNEL);
5570 	if (!t)
5571 		goto out;
5572 
5573 	for (i = 0; t->addrconf_vars[i].data; i++) {
5574 		t->addrconf_vars[i].data += (char *)p - (char *)&ipv6_devconf;
5575 		t->addrconf_vars[i].extra1 = idev; /* embedded; no ref */
5576 		t->addrconf_vars[i].extra2 = net;
5577 	}
5578 
5579 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
5580 
5581 	t->sysctl_header = register_net_sysctl(net, path, t->addrconf_vars);
5582 	if (!t->sysctl_header)
5583 		goto free;
5584 
5585 	p->sysctl = t;
5586 	return 0;
5587 
5588 free:
5589 	kfree(t);
5590 out:
5591 	return -ENOBUFS;
5592 }
5593 
5594 static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
5595 {
5596 	struct addrconf_sysctl_table *t;
5597 
5598 	if (!p->sysctl)
5599 		return;
5600 
5601 	t = p->sysctl;
5602 	p->sysctl = NULL;
5603 	unregister_net_sysctl_table(t->sysctl_header);
5604 	kfree(t);
5605 }
5606 
5607 static int addrconf_sysctl_register(struct inet6_dev *idev)
5608 {
5609 	int err;
5610 
5611 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
5612 		return -EINVAL;
5613 
5614 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
5615 				    &ndisc_ifinfo_sysctl_change);
5616 	if (err)
5617 		return err;
5618 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
5619 					 idev, &idev->cnf);
5620 	if (err)
5621 		neigh_sysctl_unregister(idev->nd_parms);
5622 
5623 	return err;
5624 }
5625 
5626 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
5627 {
5628 	__addrconf_sysctl_unregister(&idev->cnf);
5629 	neigh_sysctl_unregister(idev->nd_parms);
5630 }
5631 
5632 
5633 #endif
5634 
5635 static int __net_init addrconf_init_net(struct net *net)
5636 {
5637 	int err = -ENOMEM;
5638 	struct ipv6_devconf *all, *dflt;
5639 
5640 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
5641 	if (!all)
5642 		goto err_alloc_all;
5643 
5644 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
5645 	if (!dflt)
5646 		goto err_alloc_dflt;
5647 
5648 	/* these will be inherited by all namespaces */
5649 	dflt->autoconf = ipv6_defaults.autoconf;
5650 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
5651 
5652 	dflt->stable_secret.initialized = false;
5653 	all->stable_secret.initialized = false;
5654 
5655 	net->ipv6.devconf_all = all;
5656 	net->ipv6.devconf_dflt = dflt;
5657 
5658 #ifdef CONFIG_SYSCTL
5659 	err = __addrconf_sysctl_register(net, "all", NULL, all);
5660 	if (err < 0)
5661 		goto err_reg_all;
5662 
5663 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
5664 	if (err < 0)
5665 		goto err_reg_dflt;
5666 #endif
5667 	return 0;
5668 
5669 #ifdef CONFIG_SYSCTL
5670 err_reg_dflt:
5671 	__addrconf_sysctl_unregister(all);
5672 err_reg_all:
5673 	kfree(dflt);
5674 #endif
5675 err_alloc_dflt:
5676 	kfree(all);
5677 err_alloc_all:
5678 	return err;
5679 }
5680 
5681 static void __net_exit addrconf_exit_net(struct net *net)
5682 {
5683 #ifdef CONFIG_SYSCTL
5684 	__addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
5685 	__addrconf_sysctl_unregister(net->ipv6.devconf_all);
5686 #endif
5687 	kfree(net->ipv6.devconf_dflt);
5688 	kfree(net->ipv6.devconf_all);
5689 }
5690 
5691 static struct pernet_operations addrconf_ops = {
5692 	.init = addrconf_init_net,
5693 	.exit = addrconf_exit_net,
5694 };
5695 
5696 static struct rtnl_af_ops inet6_ops __read_mostly = {
5697 	.family		  = AF_INET6,
5698 	.fill_link_af	  = inet6_fill_link_af,
5699 	.get_link_af_size = inet6_get_link_af_size,
5700 	.validate_link_af = inet6_validate_link_af,
5701 	.set_link_af	  = inet6_set_link_af,
5702 };
5703 
5704 /*
5705  *	Init / cleanup code
5706  */
5707 
5708 int __init addrconf_init(void)
5709 {
5710 	struct inet6_dev *idev;
5711 	int i, err;
5712 
5713 	err = ipv6_addr_label_init();
5714 	if (err < 0) {
5715 		pr_crit("%s: cannot initialize default policy table: %d\n",
5716 			__func__, err);
5717 		goto out;
5718 	}
5719 
5720 	err = register_pernet_subsys(&addrconf_ops);
5721 	if (err < 0)
5722 		goto out_addrlabel;
5723 
5724 	addrconf_wq = create_workqueue("ipv6_addrconf");
5725 	if (!addrconf_wq) {
5726 		err = -ENOMEM;
5727 		goto out_nowq;
5728 	}
5729 
5730 	/* The addrconf netdev notifier requires that loopback_dev
5731 	 * has it's ipv6 private information allocated and setup
5732 	 * before it can bring up and give link-local addresses
5733 	 * to other devices which are up.
5734 	 *
5735 	 * Unfortunately, loopback_dev is not necessarily the first
5736 	 * entry in the global dev_base list of net devices.  In fact,
5737 	 * it is likely to be the very last entry on that list.
5738 	 * So this causes the notifier registry below to try and
5739 	 * give link-local addresses to all devices besides loopback_dev
5740 	 * first, then loopback_dev, which cases all the non-loopback_dev
5741 	 * devices to fail to get a link-local address.
5742 	 *
5743 	 * So, as a temporary fix, allocate the ipv6 structure for
5744 	 * loopback_dev first by hand.
5745 	 * Longer term, all of the dependencies ipv6 has upon the loopback
5746 	 * device and it being up should be removed.
5747 	 */
5748 	rtnl_lock();
5749 	idev = ipv6_add_dev(init_net.loopback_dev);
5750 	rtnl_unlock();
5751 	if (IS_ERR(idev)) {
5752 		err = PTR_ERR(idev);
5753 		goto errlo;
5754 	}
5755 
5756 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
5757 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
5758 
5759 	register_netdevice_notifier(&ipv6_dev_notf);
5760 
5761 	addrconf_verify();
5762 
5763 	rtnl_af_register(&inet6_ops);
5764 
5765 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
5766 			      NULL);
5767 	if (err < 0)
5768 		goto errout;
5769 
5770 	/* Only the first call to __rtnl_register can fail */
5771 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, NULL);
5772 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, NULL);
5773 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
5774 			inet6_dump_ifaddr, NULL);
5775 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
5776 			inet6_dump_ifmcaddr, NULL);
5777 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
5778 			inet6_dump_ifacaddr, NULL);
5779 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
5780 			inet6_netconf_dump_devconf, NULL);
5781 
5782 	ipv6_addr_label_rtnl_register();
5783 
5784 	return 0;
5785 errout:
5786 	rtnl_af_unregister(&inet6_ops);
5787 	unregister_netdevice_notifier(&ipv6_dev_notf);
5788 errlo:
5789 	destroy_workqueue(addrconf_wq);
5790 out_nowq:
5791 	unregister_pernet_subsys(&addrconf_ops);
5792 out_addrlabel:
5793 	ipv6_addr_label_cleanup();
5794 out:
5795 	return err;
5796 }
5797 
5798 void addrconf_cleanup(void)
5799 {
5800 	struct net_device *dev;
5801 	int i;
5802 
5803 	unregister_netdevice_notifier(&ipv6_dev_notf);
5804 	unregister_pernet_subsys(&addrconf_ops);
5805 	ipv6_addr_label_cleanup();
5806 
5807 	rtnl_lock();
5808 
5809 	__rtnl_af_unregister(&inet6_ops);
5810 
5811 	/* clean dev list */
5812 	for_each_netdev(&init_net, dev) {
5813 		if (__in6_dev_get(dev) == NULL)
5814 			continue;
5815 		addrconf_ifdown(dev, 1);
5816 	}
5817 	addrconf_ifdown(init_net.loopback_dev, 2);
5818 
5819 	/*
5820 	 *	Check hash table.
5821 	 */
5822 	spin_lock_bh(&addrconf_hash_lock);
5823 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
5824 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
5825 	spin_unlock_bh(&addrconf_hash_lock);
5826 	cancel_delayed_work(&addr_chk_work);
5827 	rtnl_unlock();
5828 
5829 	destroy_workqueue(addrconf_wq);
5830 }
5831