xref: /openbmc/linux/net/ipv6/addrconf.c (revision 293d5b43)
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/6lowpan.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 <net/l3mdev.h>
85 #include <linux/if_tunnel.h>
86 #include <linux/rtnetlink.h>
87 #include <linux/netconf.h>
88 #include <linux/random.h>
89 #include <linux/uaccess.h>
90 #include <asm/unaligned.h>
91 
92 #include <linux/proc_fs.h>
93 #include <linux/seq_file.h>
94 #include <linux/export.h>
95 
96 /* Set to 3 to get tracing... */
97 #define ACONF_DEBUG 2
98 
99 #if ACONF_DEBUG >= 3
100 #define ADBG(fmt, ...) printk(fmt, ##__VA_ARGS__)
101 #else
102 #define ADBG(fmt, ...) do { if (0) printk(fmt, ##__VA_ARGS__); } while (0)
103 #endif
104 
105 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
106 
107 #define IPV6_MAX_STRLEN \
108 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
109 
110 static inline u32 cstamp_delta(unsigned long cstamp)
111 {
112 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
113 }
114 
115 #ifdef CONFIG_SYSCTL
116 static int addrconf_sysctl_register(struct inet6_dev *idev);
117 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
118 #else
119 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
120 {
121 	return 0;
122 }
123 
124 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
125 {
126 }
127 #endif
128 
129 static void __ipv6_regen_rndid(struct inet6_dev *idev);
130 static void __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
131 static void ipv6_regen_rndid(unsigned long data);
132 
133 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
134 static int ipv6_count_addresses(struct inet6_dev *idev);
135 static int ipv6_generate_stable_address(struct in6_addr *addr,
136 					u8 dad_count,
137 					const struct inet6_dev *idev);
138 
139 /*
140  *	Configured unicast address hash table
141  */
142 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
143 static DEFINE_SPINLOCK(addrconf_hash_lock);
144 
145 static void addrconf_verify(void);
146 static void addrconf_verify_rtnl(void);
147 static void addrconf_verify_work(struct work_struct *);
148 
149 static struct workqueue_struct *addrconf_wq;
150 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
151 
152 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
153 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
154 
155 static void addrconf_type_change(struct net_device *dev,
156 				 unsigned long event);
157 static int addrconf_ifdown(struct net_device *dev, int how);
158 
159 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
160 						  int plen,
161 						  const struct net_device *dev,
162 						  u32 flags, u32 noflags);
163 
164 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
165 static void addrconf_dad_work(struct work_struct *w);
166 static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
167 static void addrconf_dad_run(struct inet6_dev *idev);
168 static void addrconf_rs_timer(unsigned long data);
169 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
170 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
171 
172 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
173 				struct prefix_info *pinfo);
174 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
175 			       struct net_device *dev);
176 
177 static struct ipv6_devconf ipv6_devconf __read_mostly = {
178 	.forwarding		= 0,
179 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
180 	.mtu6			= IPV6_MIN_MTU,
181 	.accept_ra		= 1,
182 	.accept_redirects	= 1,
183 	.autoconf		= 1,
184 	.force_mld_version	= 0,
185 	.mldv1_unsolicited_report_interval = 10 * HZ,
186 	.mldv2_unsolicited_report_interval = HZ,
187 	.dad_transmits		= 1,
188 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
189 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
190 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
191 	.use_tempaddr		= 0,
192 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
193 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
194 	.regen_max_retry	= REGEN_MAX_RETRY,
195 	.max_desync_factor	= MAX_DESYNC_FACTOR,
196 	.max_addresses		= IPV6_MAX_ADDRESSES,
197 	.accept_ra_defrtr	= 1,
198 	.accept_ra_from_local	= 0,
199 	.accept_ra_min_hop_limit= 1,
200 	.accept_ra_pinfo	= 1,
201 #ifdef CONFIG_IPV6_ROUTER_PREF
202 	.accept_ra_rtr_pref	= 1,
203 	.rtr_probe_interval	= 60 * HZ,
204 #ifdef CONFIG_IPV6_ROUTE_INFO
205 	.accept_ra_rt_info_max_plen = 0,
206 #endif
207 #endif
208 	.proxy_ndp		= 0,
209 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
210 	.disable_ipv6		= 0,
211 	.accept_dad		= 1,
212 	.suppress_frag_ndisc	= 1,
213 	.accept_ra_mtu		= 1,
214 	.stable_secret		= {
215 		.initialized = false,
216 	},
217 	.use_oif_addrs_only	= 0,
218 	.ignore_routes_with_linkdown = 0,
219 	.keep_addr_on_down	= 0,
220 };
221 
222 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
223 	.forwarding		= 0,
224 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
225 	.mtu6			= IPV6_MIN_MTU,
226 	.accept_ra		= 1,
227 	.accept_redirects	= 1,
228 	.autoconf		= 1,
229 	.force_mld_version	= 0,
230 	.mldv1_unsolicited_report_interval = 10 * HZ,
231 	.mldv2_unsolicited_report_interval = HZ,
232 	.dad_transmits		= 1,
233 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
234 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
235 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
236 	.use_tempaddr		= 0,
237 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
238 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
239 	.regen_max_retry	= REGEN_MAX_RETRY,
240 	.max_desync_factor	= MAX_DESYNC_FACTOR,
241 	.max_addresses		= IPV6_MAX_ADDRESSES,
242 	.accept_ra_defrtr	= 1,
243 	.accept_ra_from_local	= 0,
244 	.accept_ra_min_hop_limit= 1,
245 	.accept_ra_pinfo	= 1,
246 #ifdef CONFIG_IPV6_ROUTER_PREF
247 	.accept_ra_rtr_pref	= 1,
248 	.rtr_probe_interval	= 60 * HZ,
249 #ifdef CONFIG_IPV6_ROUTE_INFO
250 	.accept_ra_rt_info_max_plen = 0,
251 #endif
252 #endif
253 	.proxy_ndp		= 0,
254 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
255 	.disable_ipv6		= 0,
256 	.accept_dad		= 1,
257 	.suppress_frag_ndisc	= 1,
258 	.accept_ra_mtu		= 1,
259 	.stable_secret		= {
260 		.initialized = false,
261 	},
262 	.use_oif_addrs_only	= 0,
263 	.ignore_routes_with_linkdown = 0,
264 	.keep_addr_on_down	= 0,
265 };
266 
267 /* Check if a valid qdisc is available */
268 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
269 {
270 	return !qdisc_tx_is_noop(dev);
271 }
272 
273 static void addrconf_del_rs_timer(struct inet6_dev *idev)
274 {
275 	if (del_timer(&idev->rs_timer))
276 		__in6_dev_put(idev);
277 }
278 
279 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
280 {
281 	if (cancel_delayed_work(&ifp->dad_work))
282 		__in6_ifa_put(ifp);
283 }
284 
285 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
286 				  unsigned long when)
287 {
288 	if (!timer_pending(&idev->rs_timer))
289 		in6_dev_hold(idev);
290 	mod_timer(&idev->rs_timer, jiffies + when);
291 }
292 
293 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
294 				   unsigned long delay)
295 {
296 	if (!delayed_work_pending(&ifp->dad_work))
297 		in6_ifa_hold(ifp);
298 	mod_delayed_work(addrconf_wq, &ifp->dad_work, delay);
299 }
300 
301 static int snmp6_alloc_dev(struct inet6_dev *idev)
302 {
303 	int i;
304 
305 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
306 	if (!idev->stats.ipv6)
307 		goto err_ip;
308 
309 	for_each_possible_cpu(i) {
310 		struct ipstats_mib *addrconf_stats;
311 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
312 		u64_stats_init(&addrconf_stats->syncp);
313 	}
314 
315 
316 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
317 					GFP_KERNEL);
318 	if (!idev->stats.icmpv6dev)
319 		goto err_icmp;
320 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
321 					   GFP_KERNEL);
322 	if (!idev->stats.icmpv6msgdev)
323 		goto err_icmpmsg;
324 
325 	return 0;
326 
327 err_icmpmsg:
328 	kfree(idev->stats.icmpv6dev);
329 err_icmp:
330 	free_percpu(idev->stats.ipv6);
331 err_ip:
332 	return -ENOMEM;
333 }
334 
335 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
336 {
337 	struct inet6_dev *ndev;
338 	int err = -ENOMEM;
339 
340 	ASSERT_RTNL();
341 
342 	if (dev->mtu < IPV6_MIN_MTU)
343 		return ERR_PTR(-EINVAL);
344 
345 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
346 	if (!ndev)
347 		return ERR_PTR(err);
348 
349 	rwlock_init(&ndev->lock);
350 	ndev->dev = dev;
351 	INIT_LIST_HEAD(&ndev->addr_list);
352 	setup_timer(&ndev->rs_timer, addrconf_rs_timer,
353 		    (unsigned long)ndev);
354 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
355 
356 	if (ndev->cnf.stable_secret.initialized)
357 		ndev->addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
358 	else
359 		ndev->addr_gen_mode = IN6_ADDR_GEN_MODE_EUI64;
360 
361 	ndev->cnf.mtu6 = dev->mtu;
362 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
363 	if (!ndev->nd_parms) {
364 		kfree(ndev);
365 		return ERR_PTR(err);
366 	}
367 	if (ndev->cnf.forwarding)
368 		dev_disable_lro(dev);
369 	/* We refer to the device */
370 	dev_hold(dev);
371 
372 	if (snmp6_alloc_dev(ndev) < 0) {
373 		ADBG(KERN_WARNING
374 			"%s: cannot allocate memory for statistics; dev=%s.\n",
375 			__func__, dev->name);
376 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
377 		dev_put(dev);
378 		kfree(ndev);
379 		return ERR_PTR(err);
380 	}
381 
382 	if (snmp6_register_dev(ndev) < 0) {
383 		ADBG(KERN_WARNING
384 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
385 			__func__, dev->name);
386 		goto err_release;
387 	}
388 
389 	/* One reference from device.  We must do this before
390 	 * we invoke __ipv6_regen_rndid().
391 	 */
392 	in6_dev_hold(ndev);
393 
394 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
395 		ndev->cnf.accept_dad = -1;
396 
397 #if IS_ENABLED(CONFIG_IPV6_SIT)
398 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
399 		pr_info("%s: Disabled Multicast RS\n", dev->name);
400 		ndev->cnf.rtr_solicits = 0;
401 	}
402 #endif
403 
404 	INIT_LIST_HEAD(&ndev->tempaddr_list);
405 	setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
406 	if ((dev->flags&IFF_LOOPBACK) ||
407 	    dev->type == ARPHRD_TUNNEL ||
408 	    dev->type == ARPHRD_TUNNEL6 ||
409 	    dev->type == ARPHRD_SIT ||
410 	    dev->type == ARPHRD_NONE) {
411 		ndev->cnf.use_tempaddr = -1;
412 	} else {
413 		in6_dev_hold(ndev);
414 		ipv6_regen_rndid((unsigned long) ndev);
415 	}
416 
417 	ndev->token = in6addr_any;
418 
419 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
420 		ndev->if_flags |= IF_READY;
421 
422 	ipv6_mc_init_dev(ndev);
423 	ndev->tstamp = jiffies;
424 	err = addrconf_sysctl_register(ndev);
425 	if (err) {
426 		ipv6_mc_destroy_dev(ndev);
427 		del_timer(&ndev->regen_timer);
428 		snmp6_unregister_dev(ndev);
429 		goto err_release;
430 	}
431 	/* protected by rtnl_lock */
432 	rcu_assign_pointer(dev->ip6_ptr, ndev);
433 
434 	/* Join interface-local all-node multicast group */
435 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
436 
437 	/* Join all-node multicast group */
438 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
439 
440 	/* Join all-router multicast group if forwarding is set */
441 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
442 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
443 
444 	return ndev;
445 
446 err_release:
447 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
448 	ndev->dead = 1;
449 	in6_dev_finish_destroy(ndev);
450 	return ERR_PTR(err);
451 }
452 
453 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
454 {
455 	struct inet6_dev *idev;
456 
457 	ASSERT_RTNL();
458 
459 	idev = __in6_dev_get(dev);
460 	if (!idev) {
461 		idev = ipv6_add_dev(dev);
462 		if (IS_ERR(idev))
463 			return NULL;
464 	}
465 
466 	if (dev->flags&IFF_UP)
467 		ipv6_mc_up(idev);
468 	return idev;
469 }
470 
471 static int inet6_netconf_msgsize_devconf(int type)
472 {
473 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
474 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
475 	bool all = false;
476 
477 	if (type == NETCONFA_ALL)
478 		all = true;
479 
480 	if (all || type == NETCONFA_FORWARDING)
481 		size += nla_total_size(4);
482 #ifdef CONFIG_IPV6_MROUTE
483 	if (all || type == NETCONFA_MC_FORWARDING)
484 		size += nla_total_size(4);
485 #endif
486 	if (all || type == NETCONFA_PROXY_NEIGH)
487 		size += nla_total_size(4);
488 
489 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
490 		size += nla_total_size(4);
491 
492 	return size;
493 }
494 
495 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
496 				      struct ipv6_devconf *devconf, u32 portid,
497 				      u32 seq, int event, unsigned int flags,
498 				      int type)
499 {
500 	struct nlmsghdr  *nlh;
501 	struct netconfmsg *ncm;
502 	bool all = false;
503 
504 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
505 			flags);
506 	if (!nlh)
507 		return -EMSGSIZE;
508 
509 	if (type == NETCONFA_ALL)
510 		all = true;
511 
512 	ncm = nlmsg_data(nlh);
513 	ncm->ncm_family = AF_INET6;
514 
515 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
516 		goto nla_put_failure;
517 
518 	if ((all || type == NETCONFA_FORWARDING) &&
519 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
520 		goto nla_put_failure;
521 #ifdef CONFIG_IPV6_MROUTE
522 	if ((all || type == NETCONFA_MC_FORWARDING) &&
523 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
524 			devconf->mc_forwarding) < 0)
525 		goto nla_put_failure;
526 #endif
527 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
528 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
529 		goto nla_put_failure;
530 
531 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
532 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
533 			devconf->ignore_routes_with_linkdown) < 0)
534 		goto nla_put_failure;
535 
536 	nlmsg_end(skb, nlh);
537 	return 0;
538 
539 nla_put_failure:
540 	nlmsg_cancel(skb, nlh);
541 	return -EMSGSIZE;
542 }
543 
544 void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
545 				  struct ipv6_devconf *devconf)
546 {
547 	struct sk_buff *skb;
548 	int err = -ENOBUFS;
549 
550 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
551 	if (!skb)
552 		goto errout;
553 
554 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
555 					 RTM_NEWNETCONF, 0, type);
556 	if (err < 0) {
557 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
558 		WARN_ON(err == -EMSGSIZE);
559 		kfree_skb(skb);
560 		goto errout;
561 	}
562 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
563 	return;
564 errout:
565 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
566 }
567 
568 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
569 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
570 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
571 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
572 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
573 };
574 
575 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
576 				     struct nlmsghdr *nlh)
577 {
578 	struct net *net = sock_net(in_skb->sk);
579 	struct nlattr *tb[NETCONFA_MAX+1];
580 	struct netconfmsg *ncm;
581 	struct sk_buff *skb;
582 	struct ipv6_devconf *devconf;
583 	struct inet6_dev *in6_dev;
584 	struct net_device *dev;
585 	int ifindex;
586 	int err;
587 
588 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
589 			  devconf_ipv6_policy);
590 	if (err < 0)
591 		goto errout;
592 
593 	err = -EINVAL;
594 	if (!tb[NETCONFA_IFINDEX])
595 		goto errout;
596 
597 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
598 	switch (ifindex) {
599 	case NETCONFA_IFINDEX_ALL:
600 		devconf = net->ipv6.devconf_all;
601 		break;
602 	case NETCONFA_IFINDEX_DEFAULT:
603 		devconf = net->ipv6.devconf_dflt;
604 		break;
605 	default:
606 		dev = __dev_get_by_index(net, ifindex);
607 		if (!dev)
608 			goto errout;
609 		in6_dev = __in6_dev_get(dev);
610 		if (!in6_dev)
611 			goto errout;
612 		devconf = &in6_dev->cnf;
613 		break;
614 	}
615 
616 	err = -ENOBUFS;
617 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_ATOMIC);
618 	if (!skb)
619 		goto errout;
620 
621 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
622 					 NETLINK_CB(in_skb).portid,
623 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
624 					 NETCONFA_ALL);
625 	if (err < 0) {
626 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
627 		WARN_ON(err == -EMSGSIZE);
628 		kfree_skb(skb);
629 		goto errout;
630 	}
631 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
632 errout:
633 	return err;
634 }
635 
636 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
637 				      struct netlink_callback *cb)
638 {
639 	struct net *net = sock_net(skb->sk);
640 	int h, s_h;
641 	int idx, s_idx;
642 	struct net_device *dev;
643 	struct inet6_dev *idev;
644 	struct hlist_head *head;
645 
646 	s_h = cb->args[0];
647 	s_idx = idx = cb->args[1];
648 
649 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
650 		idx = 0;
651 		head = &net->dev_index_head[h];
652 		rcu_read_lock();
653 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
654 			  net->dev_base_seq;
655 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
656 			if (idx < s_idx)
657 				goto cont;
658 			idev = __in6_dev_get(dev);
659 			if (!idev)
660 				goto cont;
661 
662 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
663 						       &idev->cnf,
664 						       NETLINK_CB(cb->skb).portid,
665 						       cb->nlh->nlmsg_seq,
666 						       RTM_NEWNETCONF,
667 						       NLM_F_MULTI,
668 						       NETCONFA_ALL) < 0) {
669 				rcu_read_unlock();
670 				goto done;
671 			}
672 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
673 cont:
674 			idx++;
675 		}
676 		rcu_read_unlock();
677 	}
678 	if (h == NETDEV_HASHENTRIES) {
679 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
680 					       net->ipv6.devconf_all,
681 					       NETLINK_CB(cb->skb).portid,
682 					       cb->nlh->nlmsg_seq,
683 					       RTM_NEWNETCONF, NLM_F_MULTI,
684 					       NETCONFA_ALL) < 0)
685 			goto done;
686 		else
687 			h++;
688 	}
689 	if (h == NETDEV_HASHENTRIES + 1) {
690 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
691 					       net->ipv6.devconf_dflt,
692 					       NETLINK_CB(cb->skb).portid,
693 					       cb->nlh->nlmsg_seq,
694 					       RTM_NEWNETCONF, NLM_F_MULTI,
695 					       NETCONFA_ALL) < 0)
696 			goto done;
697 		else
698 			h++;
699 	}
700 done:
701 	cb->args[0] = h;
702 	cb->args[1] = idx;
703 
704 	return skb->len;
705 }
706 
707 #ifdef CONFIG_SYSCTL
708 static void dev_forward_change(struct inet6_dev *idev)
709 {
710 	struct net_device *dev;
711 	struct inet6_ifaddr *ifa;
712 
713 	if (!idev)
714 		return;
715 	dev = idev->dev;
716 	if (idev->cnf.forwarding)
717 		dev_disable_lro(dev);
718 	if (dev->flags & IFF_MULTICAST) {
719 		if (idev->cnf.forwarding) {
720 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
721 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
722 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
723 		} else {
724 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
725 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
726 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
727 		}
728 	}
729 
730 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
731 		if (ifa->flags&IFA_F_TENTATIVE)
732 			continue;
733 		if (idev->cnf.forwarding)
734 			addrconf_join_anycast(ifa);
735 		else
736 			addrconf_leave_anycast(ifa);
737 	}
738 	inet6_netconf_notify_devconf(dev_net(dev), NETCONFA_FORWARDING,
739 				     dev->ifindex, &idev->cnf);
740 }
741 
742 
743 static void addrconf_forward_change(struct net *net, __s32 newf)
744 {
745 	struct net_device *dev;
746 	struct inet6_dev *idev;
747 
748 	for_each_netdev(net, dev) {
749 		idev = __in6_dev_get(dev);
750 		if (idev) {
751 			int changed = (!idev->cnf.forwarding) ^ (!newf);
752 			idev->cnf.forwarding = newf;
753 			if (changed)
754 				dev_forward_change(idev);
755 		}
756 	}
757 }
758 
759 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
760 {
761 	struct net *net;
762 	int old;
763 
764 	if (!rtnl_trylock())
765 		return restart_syscall();
766 
767 	net = (struct net *)table->extra2;
768 	old = *p;
769 	*p = newf;
770 
771 	if (p == &net->ipv6.devconf_dflt->forwarding) {
772 		if ((!newf) ^ (!old))
773 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
774 						     NETCONFA_IFINDEX_DEFAULT,
775 						     net->ipv6.devconf_dflt);
776 		rtnl_unlock();
777 		return 0;
778 	}
779 
780 	if (p == &net->ipv6.devconf_all->forwarding) {
781 		net->ipv6.devconf_dflt->forwarding = newf;
782 		addrconf_forward_change(net, newf);
783 		if ((!newf) ^ (!old))
784 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
785 						     NETCONFA_IFINDEX_ALL,
786 						     net->ipv6.devconf_all);
787 	} else if ((!newf) ^ (!old))
788 		dev_forward_change((struct inet6_dev *)table->extra1);
789 	rtnl_unlock();
790 
791 	if (newf)
792 		rt6_purge_dflt_routers(net);
793 	return 1;
794 }
795 
796 static void addrconf_linkdown_change(struct net *net, __s32 newf)
797 {
798 	struct net_device *dev;
799 	struct inet6_dev *idev;
800 
801 	for_each_netdev(net, dev) {
802 		idev = __in6_dev_get(dev);
803 		if (idev) {
804 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
805 
806 			idev->cnf.ignore_routes_with_linkdown = newf;
807 			if (changed)
808 				inet6_netconf_notify_devconf(dev_net(dev),
809 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
810 							     dev->ifindex,
811 							     &idev->cnf);
812 		}
813 	}
814 }
815 
816 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
817 {
818 	struct net *net;
819 	int old;
820 
821 	if (!rtnl_trylock())
822 		return restart_syscall();
823 
824 	net = (struct net *)table->extra2;
825 	old = *p;
826 	*p = newf;
827 
828 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
829 		if ((!newf) ^ (!old))
830 			inet6_netconf_notify_devconf(net,
831 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
832 						     NETCONFA_IFINDEX_DEFAULT,
833 						     net->ipv6.devconf_dflt);
834 		rtnl_unlock();
835 		return 0;
836 	}
837 
838 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
839 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
840 		addrconf_linkdown_change(net, newf);
841 		if ((!newf) ^ (!old))
842 			inet6_netconf_notify_devconf(net,
843 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
844 						     NETCONFA_IFINDEX_ALL,
845 						     net->ipv6.devconf_all);
846 	}
847 	rtnl_unlock();
848 
849 	return 1;
850 }
851 
852 #endif
853 
854 /* Nobody refers to this ifaddr, destroy it */
855 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
856 {
857 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
858 
859 #ifdef NET_REFCNT_DEBUG
860 	pr_debug("%s\n", __func__);
861 #endif
862 
863 	in6_dev_put(ifp->idev);
864 
865 	if (cancel_delayed_work(&ifp->dad_work))
866 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
867 			  ifp);
868 
869 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
870 		pr_warn("Freeing alive inet6 address %p\n", ifp);
871 		return;
872 	}
873 	ip6_rt_put(ifp->rt);
874 
875 	kfree_rcu(ifp, rcu);
876 }
877 
878 static void
879 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
880 {
881 	struct list_head *p;
882 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
883 
884 	/*
885 	 * Each device address list is sorted in order of scope -
886 	 * global before linklocal.
887 	 */
888 	list_for_each(p, &idev->addr_list) {
889 		struct inet6_ifaddr *ifa
890 			= list_entry(p, struct inet6_ifaddr, if_list);
891 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
892 			break;
893 	}
894 
895 	list_add_tail(&ifp->if_list, p);
896 }
897 
898 static u32 inet6_addr_hash(const struct in6_addr *addr)
899 {
900 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
901 }
902 
903 /* On success it returns ifp with increased reference count */
904 
905 static struct inet6_ifaddr *
906 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
907 	      const struct in6_addr *peer_addr, int pfxlen,
908 	      int scope, u32 flags, u32 valid_lft, u32 prefered_lft)
909 {
910 	struct inet6_ifaddr *ifa = NULL;
911 	struct rt6_info *rt;
912 	unsigned int hash;
913 	int err = 0;
914 	int addr_type = ipv6_addr_type(addr);
915 
916 	if (addr_type == IPV6_ADDR_ANY ||
917 	    addr_type & IPV6_ADDR_MULTICAST ||
918 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
919 	     addr_type & IPV6_ADDR_LOOPBACK))
920 		return ERR_PTR(-EADDRNOTAVAIL);
921 
922 	rcu_read_lock_bh();
923 	if (idev->dead) {
924 		err = -ENODEV;			/*XXX*/
925 		goto out2;
926 	}
927 
928 	if (idev->cnf.disable_ipv6) {
929 		err = -EACCES;
930 		goto out2;
931 	}
932 
933 	spin_lock(&addrconf_hash_lock);
934 
935 	/* Ignore adding duplicate addresses on an interface */
936 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
937 		ADBG("ipv6_add_addr: already assigned\n");
938 		err = -EEXIST;
939 		goto out;
940 	}
941 
942 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
943 
944 	if (!ifa) {
945 		ADBG("ipv6_add_addr: malloc failed\n");
946 		err = -ENOBUFS;
947 		goto out;
948 	}
949 
950 	rt = addrconf_dst_alloc(idev, addr, false);
951 	if (IS_ERR(rt)) {
952 		err = PTR_ERR(rt);
953 		goto out;
954 	}
955 
956 	neigh_parms_data_state_setall(idev->nd_parms);
957 
958 	ifa->addr = *addr;
959 	if (peer_addr)
960 		ifa->peer_addr = *peer_addr;
961 
962 	spin_lock_init(&ifa->lock);
963 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
964 	INIT_HLIST_NODE(&ifa->addr_lst);
965 	ifa->scope = scope;
966 	ifa->prefix_len = pfxlen;
967 	ifa->flags = flags | IFA_F_TENTATIVE;
968 	ifa->valid_lft = valid_lft;
969 	ifa->prefered_lft = prefered_lft;
970 	ifa->cstamp = ifa->tstamp = jiffies;
971 	ifa->tokenized = false;
972 
973 	ifa->rt = rt;
974 
975 	ifa->idev = idev;
976 	in6_dev_hold(idev);
977 	/* For caller */
978 	in6_ifa_hold(ifa);
979 
980 	/* Add to big hash table */
981 	hash = inet6_addr_hash(addr);
982 
983 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
984 	spin_unlock(&addrconf_hash_lock);
985 
986 	write_lock(&idev->lock);
987 	/* Add to inet6_dev unicast addr list. */
988 	ipv6_link_dev_addr(idev, ifa);
989 
990 	if (ifa->flags&IFA_F_TEMPORARY) {
991 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
992 		in6_ifa_hold(ifa);
993 	}
994 
995 	in6_ifa_hold(ifa);
996 	write_unlock(&idev->lock);
997 out2:
998 	rcu_read_unlock_bh();
999 
1000 	if (likely(err == 0))
1001 		inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1002 	else {
1003 		kfree(ifa);
1004 		ifa = ERR_PTR(err);
1005 	}
1006 
1007 	return ifa;
1008 out:
1009 	spin_unlock(&addrconf_hash_lock);
1010 	goto out2;
1011 }
1012 
1013 enum cleanup_prefix_rt_t {
1014 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1015 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1016 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1017 };
1018 
1019 /*
1020  * Check, whether the prefix for ifp would still need a prefix route
1021  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1022  * constants.
1023  *
1024  * 1) we don't purge prefix if address was not permanent.
1025  *    prefix is managed by its own lifetime.
1026  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1027  * 3) if there are no addresses, delete prefix.
1028  * 4) if there are still other permanent address(es),
1029  *    corresponding prefix is still permanent.
1030  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1031  *    don't purge the prefix, assume user space is managing it.
1032  * 6) otherwise, update prefix lifetime to the
1033  *    longest valid lifetime among the corresponding
1034  *    addresses on the device.
1035  *    Note: subsequent RA will update lifetime.
1036  **/
1037 static enum cleanup_prefix_rt_t
1038 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1039 {
1040 	struct inet6_ifaddr *ifa;
1041 	struct inet6_dev *idev = ifp->idev;
1042 	unsigned long lifetime;
1043 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1044 
1045 	*expires = jiffies;
1046 
1047 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1048 		if (ifa == ifp)
1049 			continue;
1050 		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1051 				       ifp->prefix_len))
1052 			continue;
1053 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1054 			return CLEANUP_PREFIX_RT_NOP;
1055 
1056 		action = CLEANUP_PREFIX_RT_EXPIRE;
1057 
1058 		spin_lock(&ifa->lock);
1059 
1060 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1061 		/*
1062 		 * Note: Because this address is
1063 		 * not permanent, lifetime <
1064 		 * LONG_MAX / HZ here.
1065 		 */
1066 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1067 			*expires = ifa->tstamp + lifetime * HZ;
1068 		spin_unlock(&ifa->lock);
1069 	}
1070 
1071 	return action;
1072 }
1073 
1074 static void
1075 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
1076 {
1077 	struct rt6_info *rt;
1078 
1079 	rt = addrconf_get_prefix_route(&ifp->addr,
1080 				       ifp->prefix_len,
1081 				       ifp->idev->dev,
1082 				       0, RTF_GATEWAY | RTF_DEFAULT);
1083 	if (rt) {
1084 		if (del_rt)
1085 			ip6_del_rt(rt);
1086 		else {
1087 			if (!(rt->rt6i_flags & RTF_EXPIRES))
1088 				rt6_set_expires(rt, expires);
1089 			ip6_rt_put(rt);
1090 		}
1091 	}
1092 }
1093 
1094 
1095 /* This function wants to get referenced ifp and releases it before return */
1096 
1097 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1098 {
1099 	int state;
1100 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1101 	unsigned long expires;
1102 
1103 	ASSERT_RTNL();
1104 
1105 	spin_lock_bh(&ifp->lock);
1106 	state = ifp->state;
1107 	ifp->state = INET6_IFADDR_STATE_DEAD;
1108 	spin_unlock_bh(&ifp->lock);
1109 
1110 	if (state == INET6_IFADDR_STATE_DEAD)
1111 		goto out;
1112 
1113 	spin_lock_bh(&addrconf_hash_lock);
1114 	hlist_del_init_rcu(&ifp->addr_lst);
1115 	spin_unlock_bh(&addrconf_hash_lock);
1116 
1117 	write_lock_bh(&ifp->idev->lock);
1118 
1119 	if (ifp->flags&IFA_F_TEMPORARY) {
1120 		list_del(&ifp->tmp_list);
1121 		if (ifp->ifpub) {
1122 			in6_ifa_put(ifp->ifpub);
1123 			ifp->ifpub = NULL;
1124 		}
1125 		__in6_ifa_put(ifp);
1126 	}
1127 
1128 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1129 		action = check_cleanup_prefix_route(ifp, &expires);
1130 
1131 	list_del_init(&ifp->if_list);
1132 	__in6_ifa_put(ifp);
1133 
1134 	write_unlock_bh(&ifp->idev->lock);
1135 
1136 	addrconf_del_dad_work(ifp);
1137 
1138 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1139 
1140 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1141 
1142 	if (action != CLEANUP_PREFIX_RT_NOP) {
1143 		cleanup_prefix_route(ifp, expires,
1144 			action == CLEANUP_PREFIX_RT_DEL);
1145 	}
1146 
1147 	/* clean up prefsrc entries */
1148 	rt6_remove_prefsrc(ifp);
1149 out:
1150 	in6_ifa_put(ifp);
1151 }
1152 
1153 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
1154 {
1155 	struct inet6_dev *idev = ifp->idev;
1156 	struct in6_addr addr, *tmpaddr;
1157 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
1158 	unsigned long regen_advance;
1159 	int tmp_plen;
1160 	int ret = 0;
1161 	u32 addr_flags;
1162 	unsigned long now = jiffies;
1163 
1164 	write_lock_bh(&idev->lock);
1165 	if (ift) {
1166 		spin_lock_bh(&ift->lock);
1167 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1168 		spin_unlock_bh(&ift->lock);
1169 		tmpaddr = &addr;
1170 	} else {
1171 		tmpaddr = NULL;
1172 	}
1173 retry:
1174 	in6_dev_hold(idev);
1175 	if (idev->cnf.use_tempaddr <= 0) {
1176 		write_unlock_bh(&idev->lock);
1177 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1178 		in6_dev_put(idev);
1179 		ret = -1;
1180 		goto out;
1181 	}
1182 	spin_lock_bh(&ifp->lock);
1183 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1184 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1185 		spin_unlock_bh(&ifp->lock);
1186 		write_unlock_bh(&idev->lock);
1187 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1188 			__func__);
1189 		in6_dev_put(idev);
1190 		ret = -1;
1191 		goto out;
1192 	}
1193 	in6_ifa_hold(ifp);
1194 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1195 	__ipv6_try_regen_rndid(idev, tmpaddr);
1196 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1197 	age = (now - ifp->tstamp) / HZ;
1198 	tmp_valid_lft = min_t(__u32,
1199 			      ifp->valid_lft,
1200 			      idev->cnf.temp_valid_lft + age);
1201 	tmp_prefered_lft = min_t(__u32,
1202 				 ifp->prefered_lft,
1203 				 idev->cnf.temp_prefered_lft + age -
1204 				 idev->cnf.max_desync_factor);
1205 	tmp_plen = ifp->prefix_len;
1206 	tmp_tstamp = ifp->tstamp;
1207 	spin_unlock_bh(&ifp->lock);
1208 
1209 	regen_advance = idev->cnf.regen_max_retry *
1210 			idev->cnf.dad_transmits *
1211 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1212 	write_unlock_bh(&idev->lock);
1213 
1214 	/* A temporary address is created only if this calculated Preferred
1215 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1216 	 * an implementation must not create a temporary address with a zero
1217 	 * Preferred Lifetime.
1218 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1219 	 * temporary addresses being generated.
1220 	 */
1221 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1222 	if (tmp_prefered_lft <= regen_advance + age) {
1223 		in6_ifa_put(ifp);
1224 		in6_dev_put(idev);
1225 		ret = -1;
1226 		goto out;
1227 	}
1228 
1229 	addr_flags = IFA_F_TEMPORARY;
1230 	/* set in addrconf_prefix_rcv() */
1231 	if (ifp->flags & IFA_F_OPTIMISTIC)
1232 		addr_flags |= IFA_F_OPTIMISTIC;
1233 
1234 	ift = ipv6_add_addr(idev, &addr, NULL, tmp_plen,
1235 			    ipv6_addr_scope(&addr), addr_flags,
1236 			    tmp_valid_lft, tmp_prefered_lft);
1237 	if (IS_ERR(ift)) {
1238 		in6_ifa_put(ifp);
1239 		in6_dev_put(idev);
1240 		pr_info("%s: retry temporary address regeneration\n", __func__);
1241 		tmpaddr = &addr;
1242 		write_lock_bh(&idev->lock);
1243 		goto retry;
1244 	}
1245 
1246 	spin_lock_bh(&ift->lock);
1247 	ift->ifpub = ifp;
1248 	ift->cstamp = now;
1249 	ift->tstamp = tmp_tstamp;
1250 	spin_unlock_bh(&ift->lock);
1251 
1252 	addrconf_dad_start(ift);
1253 	in6_ifa_put(ift);
1254 	in6_dev_put(idev);
1255 out:
1256 	return ret;
1257 }
1258 
1259 /*
1260  *	Choose an appropriate source address (RFC3484)
1261  */
1262 enum {
1263 	IPV6_SADDR_RULE_INIT = 0,
1264 	IPV6_SADDR_RULE_LOCAL,
1265 	IPV6_SADDR_RULE_SCOPE,
1266 	IPV6_SADDR_RULE_PREFERRED,
1267 #ifdef CONFIG_IPV6_MIP6
1268 	IPV6_SADDR_RULE_HOA,
1269 #endif
1270 	IPV6_SADDR_RULE_OIF,
1271 	IPV6_SADDR_RULE_LABEL,
1272 	IPV6_SADDR_RULE_PRIVACY,
1273 	IPV6_SADDR_RULE_ORCHID,
1274 	IPV6_SADDR_RULE_PREFIX,
1275 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1276 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1277 #endif
1278 	IPV6_SADDR_RULE_MAX
1279 };
1280 
1281 struct ipv6_saddr_score {
1282 	int			rule;
1283 	int			addr_type;
1284 	struct inet6_ifaddr	*ifa;
1285 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1286 	int			scopedist;
1287 	int			matchlen;
1288 };
1289 
1290 struct ipv6_saddr_dst {
1291 	const struct in6_addr *addr;
1292 	int ifindex;
1293 	int scope;
1294 	int label;
1295 	unsigned int prefs;
1296 };
1297 
1298 static inline int ipv6_saddr_preferred(int type)
1299 {
1300 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1301 		return 1;
1302 	return 0;
1303 }
1304 
1305 static inline bool ipv6_use_optimistic_addr(struct inet6_dev *idev)
1306 {
1307 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1308 	return idev && idev->cnf.optimistic_dad && idev->cnf.use_optimistic;
1309 #else
1310 	return false;
1311 #endif
1312 }
1313 
1314 static int ipv6_get_saddr_eval(struct net *net,
1315 			       struct ipv6_saddr_score *score,
1316 			       struct ipv6_saddr_dst *dst,
1317 			       int i)
1318 {
1319 	int ret;
1320 
1321 	if (i <= score->rule) {
1322 		switch (i) {
1323 		case IPV6_SADDR_RULE_SCOPE:
1324 			ret = score->scopedist;
1325 			break;
1326 		case IPV6_SADDR_RULE_PREFIX:
1327 			ret = score->matchlen;
1328 			break;
1329 		default:
1330 			ret = !!test_bit(i, score->scorebits);
1331 		}
1332 		goto out;
1333 	}
1334 
1335 	switch (i) {
1336 	case IPV6_SADDR_RULE_INIT:
1337 		/* Rule 0: remember if hiscore is not ready yet */
1338 		ret = !!score->ifa;
1339 		break;
1340 	case IPV6_SADDR_RULE_LOCAL:
1341 		/* Rule 1: Prefer same address */
1342 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1343 		break;
1344 	case IPV6_SADDR_RULE_SCOPE:
1345 		/* Rule 2: Prefer appropriate scope
1346 		 *
1347 		 *      ret
1348 		 *       ^
1349 		 *    -1 |  d 15
1350 		 *    ---+--+-+---> scope
1351 		 *       |
1352 		 *       |             d is scope of the destination.
1353 		 *  B-d  |  \
1354 		 *       |   \      <- smaller scope is better if
1355 		 *  B-15 |    \        if scope is enough for destination.
1356 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1357 		 * d-C-1 | /
1358 		 *       |/         <- greater is better
1359 		 *   -C  /             if scope is not enough for destination.
1360 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1361 		 *
1362 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1363 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1364 		 * Assume B = 0 and we get C > 29.
1365 		 */
1366 		ret = __ipv6_addr_src_scope(score->addr_type);
1367 		if (ret >= dst->scope)
1368 			ret = -ret;
1369 		else
1370 			ret -= 128;	/* 30 is enough */
1371 		score->scopedist = ret;
1372 		break;
1373 	case IPV6_SADDR_RULE_PREFERRED:
1374 	    {
1375 		/* Rule 3: Avoid deprecated and optimistic addresses */
1376 		u8 avoid = IFA_F_DEPRECATED;
1377 
1378 		if (!ipv6_use_optimistic_addr(score->ifa->idev))
1379 			avoid |= IFA_F_OPTIMISTIC;
1380 		ret = ipv6_saddr_preferred(score->addr_type) ||
1381 		      !(score->ifa->flags & avoid);
1382 		break;
1383 	    }
1384 #ifdef CONFIG_IPV6_MIP6
1385 	case IPV6_SADDR_RULE_HOA:
1386 	    {
1387 		/* Rule 4: Prefer home address */
1388 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1389 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1390 		break;
1391 	    }
1392 #endif
1393 	case IPV6_SADDR_RULE_OIF:
1394 		/* Rule 5: Prefer outgoing interface */
1395 		ret = (!dst->ifindex ||
1396 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1397 		break;
1398 	case IPV6_SADDR_RULE_LABEL:
1399 		/* Rule 6: Prefer matching label */
1400 		ret = ipv6_addr_label(net,
1401 				      &score->ifa->addr, score->addr_type,
1402 				      score->ifa->idev->dev->ifindex) == dst->label;
1403 		break;
1404 	case IPV6_SADDR_RULE_PRIVACY:
1405 	    {
1406 		/* Rule 7: Prefer public address
1407 		 * Note: prefer temporary address if use_tempaddr >= 2
1408 		 */
1409 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1410 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1411 				score->ifa->idev->cnf.use_tempaddr >= 2;
1412 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1413 		break;
1414 	    }
1415 	case IPV6_SADDR_RULE_ORCHID:
1416 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1417 		 *	    non-ORCHID vs non-ORCHID
1418 		 */
1419 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1420 			ipv6_addr_orchid(dst->addr));
1421 		break;
1422 	case IPV6_SADDR_RULE_PREFIX:
1423 		/* Rule 8: Use longest matching prefix */
1424 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1425 		if (ret > score->ifa->prefix_len)
1426 			ret = score->ifa->prefix_len;
1427 		score->matchlen = ret;
1428 		break;
1429 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1430 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1431 		/* Optimistic addresses still have lower precedence than other
1432 		 * preferred addresses.
1433 		 */
1434 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1435 		break;
1436 #endif
1437 	default:
1438 		ret = 0;
1439 	}
1440 
1441 	if (ret)
1442 		__set_bit(i, score->scorebits);
1443 	score->rule = i;
1444 out:
1445 	return ret;
1446 }
1447 
1448 static int __ipv6_dev_get_saddr(struct net *net,
1449 				struct ipv6_saddr_dst *dst,
1450 				struct inet6_dev *idev,
1451 				struct ipv6_saddr_score *scores,
1452 				int hiscore_idx)
1453 {
1454 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1455 
1456 	read_lock_bh(&idev->lock);
1457 	list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1458 		int i;
1459 
1460 		/*
1461 		 * - Tentative Address (RFC2462 section 5.4)
1462 		 *  - A tentative address is not considered
1463 		 *    "assigned to an interface" in the traditional
1464 		 *    sense, unless it is also flagged as optimistic.
1465 		 * - Candidate Source Address (section 4)
1466 		 *  - In any case, anycast addresses, multicast
1467 		 *    addresses, and the unspecified address MUST
1468 		 *    NOT be included in a candidate set.
1469 		 */
1470 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1471 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1472 			continue;
1473 
1474 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1475 
1476 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1477 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1478 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1479 					    idev->dev->name);
1480 			continue;
1481 		}
1482 
1483 		score->rule = -1;
1484 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1485 
1486 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1487 			int minihiscore, miniscore;
1488 
1489 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1490 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1491 
1492 			if (minihiscore > miniscore) {
1493 				if (i == IPV6_SADDR_RULE_SCOPE &&
1494 				    score->scopedist > 0) {
1495 					/*
1496 					 * special case:
1497 					 * each remaining entry
1498 					 * has too small (not enough)
1499 					 * scope, because ifa entries
1500 					 * are sorted by their scope
1501 					 * values.
1502 					 */
1503 					goto out;
1504 				}
1505 				break;
1506 			} else if (minihiscore < miniscore) {
1507 				if (hiscore->ifa)
1508 					in6_ifa_put(hiscore->ifa);
1509 
1510 				in6_ifa_hold(score->ifa);
1511 
1512 				swap(hiscore, score);
1513 				hiscore_idx = 1 - hiscore_idx;
1514 
1515 				/* restore our iterator */
1516 				score->ifa = hiscore->ifa;
1517 
1518 				break;
1519 			}
1520 		}
1521 	}
1522 out:
1523 	read_unlock_bh(&idev->lock);
1524 	return hiscore_idx;
1525 }
1526 
1527 static int ipv6_get_saddr_master(struct net *net,
1528 				 const struct net_device *dst_dev,
1529 				 const struct net_device *master,
1530 				 struct ipv6_saddr_dst *dst,
1531 				 struct ipv6_saddr_score *scores,
1532 				 int hiscore_idx)
1533 {
1534 	struct inet6_dev *idev;
1535 
1536 	idev = __in6_dev_get(dst_dev);
1537 	if (idev)
1538 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1539 						   scores, hiscore_idx);
1540 
1541 	idev = __in6_dev_get(master);
1542 	if (idev)
1543 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1544 						   scores, hiscore_idx);
1545 
1546 	return hiscore_idx;
1547 }
1548 
1549 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1550 		       const struct in6_addr *daddr, unsigned int prefs,
1551 		       struct in6_addr *saddr)
1552 {
1553 	struct ipv6_saddr_score scores[2], *hiscore;
1554 	struct ipv6_saddr_dst dst;
1555 	struct inet6_dev *idev;
1556 	struct net_device *dev;
1557 	int dst_type;
1558 	bool use_oif_addr = false;
1559 	int hiscore_idx = 0;
1560 
1561 	dst_type = __ipv6_addr_type(daddr);
1562 	dst.addr = daddr;
1563 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1564 	dst.scope = __ipv6_addr_src_scope(dst_type);
1565 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1566 	dst.prefs = prefs;
1567 
1568 	scores[hiscore_idx].rule = -1;
1569 	scores[hiscore_idx].ifa = NULL;
1570 
1571 	rcu_read_lock();
1572 
1573 	/* Candidate Source Address (section 4)
1574 	 *  - multicast and link-local destination address,
1575 	 *    the set of candidate source address MUST only
1576 	 *    include addresses assigned to interfaces
1577 	 *    belonging to the same link as the outgoing
1578 	 *    interface.
1579 	 * (- For site-local destination addresses, the
1580 	 *    set of candidate source addresses MUST only
1581 	 *    include addresses assigned to interfaces
1582 	 *    belonging to the same site as the outgoing
1583 	 *    interface.)
1584 	 *  - "It is RECOMMENDED that the candidate source addresses
1585 	 *    be the set of unicast addresses assigned to the
1586 	 *    interface that will be used to send to the destination
1587 	 *    (the 'outgoing' interface)." (RFC 6724)
1588 	 */
1589 	if (dst_dev) {
1590 		idev = __in6_dev_get(dst_dev);
1591 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1592 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1593 		    (idev && idev->cnf.use_oif_addrs_only)) {
1594 			use_oif_addr = true;
1595 		}
1596 	}
1597 
1598 	if (use_oif_addr) {
1599 		if (idev)
1600 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1601 	} else {
1602 		const struct net_device *master;
1603 		int master_idx = 0;
1604 
1605 		/* if dst_dev exists and is enslaved to an L3 device, then
1606 		 * prefer addresses from dst_dev and then the master over
1607 		 * any other enslaved devices in the L3 domain.
1608 		 */
1609 		master = l3mdev_master_dev_rcu(dst_dev);
1610 		if (master) {
1611 			master_idx = master->ifindex;
1612 
1613 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1614 							    master, &dst,
1615 							    scores, hiscore_idx);
1616 
1617 			if (scores[hiscore_idx].ifa)
1618 				goto out;
1619 		}
1620 
1621 		for_each_netdev_rcu(net, dev) {
1622 			/* only consider addresses on devices in the
1623 			 * same L3 domain
1624 			 */
1625 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1626 				continue;
1627 			idev = __in6_dev_get(dev);
1628 			if (!idev)
1629 				continue;
1630 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1631 		}
1632 	}
1633 
1634 out:
1635 	rcu_read_unlock();
1636 
1637 	hiscore = &scores[hiscore_idx];
1638 	if (!hiscore->ifa)
1639 		return -EADDRNOTAVAIL;
1640 
1641 	*saddr = hiscore->ifa->addr;
1642 	in6_ifa_put(hiscore->ifa);
1643 	return 0;
1644 }
1645 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1646 
1647 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1648 		      u32 banned_flags)
1649 {
1650 	struct inet6_ifaddr *ifp;
1651 	int err = -EADDRNOTAVAIL;
1652 
1653 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1654 		if (ifp->scope > IFA_LINK)
1655 			break;
1656 		if (ifp->scope == IFA_LINK &&
1657 		    !(ifp->flags & banned_flags)) {
1658 			*addr = ifp->addr;
1659 			err = 0;
1660 			break;
1661 		}
1662 	}
1663 	return err;
1664 }
1665 
1666 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1667 		    u32 banned_flags)
1668 {
1669 	struct inet6_dev *idev;
1670 	int err = -EADDRNOTAVAIL;
1671 
1672 	rcu_read_lock();
1673 	idev = __in6_dev_get(dev);
1674 	if (idev) {
1675 		read_lock_bh(&idev->lock);
1676 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1677 		read_unlock_bh(&idev->lock);
1678 	}
1679 	rcu_read_unlock();
1680 	return err;
1681 }
1682 
1683 static int ipv6_count_addresses(struct inet6_dev *idev)
1684 {
1685 	int cnt = 0;
1686 	struct inet6_ifaddr *ifp;
1687 
1688 	read_lock_bh(&idev->lock);
1689 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1690 		cnt++;
1691 	read_unlock_bh(&idev->lock);
1692 	return cnt;
1693 }
1694 
1695 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1696 		  const struct net_device *dev, int strict)
1697 {
1698 	return ipv6_chk_addr_and_flags(net, addr, dev, strict, IFA_F_TENTATIVE);
1699 }
1700 EXPORT_SYMBOL(ipv6_chk_addr);
1701 
1702 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1703 			    const struct net_device *dev, int strict,
1704 			    u32 banned_flags)
1705 {
1706 	struct inet6_ifaddr *ifp;
1707 	unsigned int hash = inet6_addr_hash(addr);
1708 	u32 ifp_flags;
1709 
1710 	rcu_read_lock_bh();
1711 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1712 		if (!net_eq(dev_net(ifp->idev->dev), net))
1713 			continue;
1714 		/* Decouple optimistic from tentative for evaluation here.
1715 		 * Ban optimistic addresses explicitly, when required.
1716 		 */
1717 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1718 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1719 			    : ifp->flags;
1720 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1721 		    !(ifp_flags&banned_flags) &&
1722 		    (!dev || ifp->idev->dev == dev ||
1723 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1724 			rcu_read_unlock_bh();
1725 			return 1;
1726 		}
1727 	}
1728 
1729 	rcu_read_unlock_bh();
1730 	return 0;
1731 }
1732 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1733 
1734 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1735 			       struct net_device *dev)
1736 {
1737 	unsigned int hash = inet6_addr_hash(addr);
1738 	struct inet6_ifaddr *ifp;
1739 
1740 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1741 		if (!net_eq(dev_net(ifp->idev->dev), net))
1742 			continue;
1743 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1744 			if (!dev || ifp->idev->dev == dev)
1745 				return true;
1746 		}
1747 	}
1748 	return false;
1749 }
1750 
1751 /* Compares an address/prefix_len with addresses on device @dev.
1752  * If one is found it returns true.
1753  */
1754 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1755 	const unsigned int prefix_len, struct net_device *dev)
1756 {
1757 	struct inet6_dev *idev;
1758 	struct inet6_ifaddr *ifa;
1759 	bool ret = false;
1760 
1761 	rcu_read_lock();
1762 	idev = __in6_dev_get(dev);
1763 	if (idev) {
1764 		read_lock_bh(&idev->lock);
1765 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1766 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1767 			if (ret)
1768 				break;
1769 		}
1770 		read_unlock_bh(&idev->lock);
1771 	}
1772 	rcu_read_unlock();
1773 
1774 	return ret;
1775 }
1776 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1777 
1778 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1779 {
1780 	struct inet6_dev *idev;
1781 	struct inet6_ifaddr *ifa;
1782 	int	onlink;
1783 
1784 	onlink = 0;
1785 	rcu_read_lock();
1786 	idev = __in6_dev_get(dev);
1787 	if (idev) {
1788 		read_lock_bh(&idev->lock);
1789 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1790 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1791 						   ifa->prefix_len);
1792 			if (onlink)
1793 				break;
1794 		}
1795 		read_unlock_bh(&idev->lock);
1796 	}
1797 	rcu_read_unlock();
1798 	return onlink;
1799 }
1800 EXPORT_SYMBOL(ipv6_chk_prefix);
1801 
1802 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1803 				     struct net_device *dev, int strict)
1804 {
1805 	struct inet6_ifaddr *ifp, *result = NULL;
1806 	unsigned int hash = inet6_addr_hash(addr);
1807 
1808 	rcu_read_lock_bh();
1809 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
1810 		if (!net_eq(dev_net(ifp->idev->dev), net))
1811 			continue;
1812 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1813 			if (!dev || ifp->idev->dev == dev ||
1814 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1815 				result = ifp;
1816 				in6_ifa_hold(ifp);
1817 				break;
1818 			}
1819 		}
1820 	}
1821 	rcu_read_unlock_bh();
1822 
1823 	return result;
1824 }
1825 
1826 /* Gets referenced address, destroys ifaddr */
1827 
1828 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1829 {
1830 	if (dad_failed)
1831 		ifp->flags |= IFA_F_DADFAILED;
1832 
1833 	if (ifp->flags&IFA_F_PERMANENT) {
1834 		spin_lock_bh(&ifp->lock);
1835 		addrconf_del_dad_work(ifp);
1836 		ifp->flags |= IFA_F_TENTATIVE;
1837 		spin_unlock_bh(&ifp->lock);
1838 		if (dad_failed)
1839 			ipv6_ifa_notify(0, ifp);
1840 		in6_ifa_put(ifp);
1841 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1842 		struct inet6_ifaddr *ifpub;
1843 		spin_lock_bh(&ifp->lock);
1844 		ifpub = ifp->ifpub;
1845 		if (ifpub) {
1846 			in6_ifa_hold(ifpub);
1847 			spin_unlock_bh(&ifp->lock);
1848 			ipv6_create_tempaddr(ifpub, ifp);
1849 			in6_ifa_put(ifpub);
1850 		} else {
1851 			spin_unlock_bh(&ifp->lock);
1852 		}
1853 		ipv6_del_addr(ifp);
1854 	} else {
1855 		ipv6_del_addr(ifp);
1856 	}
1857 }
1858 
1859 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1860 {
1861 	int err = -ENOENT;
1862 
1863 	spin_lock_bh(&ifp->lock);
1864 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1865 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1866 		err = 0;
1867 	}
1868 	spin_unlock_bh(&ifp->lock);
1869 
1870 	return err;
1871 }
1872 
1873 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1874 {
1875 	struct in6_addr addr;
1876 	struct inet6_dev *idev = ifp->idev;
1877 	struct net *net = dev_net(ifp->idev->dev);
1878 
1879 	if (addrconf_dad_end(ifp)) {
1880 		in6_ifa_put(ifp);
1881 		return;
1882 	}
1883 
1884 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1885 			     ifp->idev->dev->name, &ifp->addr);
1886 
1887 	spin_lock_bh(&ifp->lock);
1888 
1889 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
1890 		int scope = ifp->scope;
1891 		u32 flags = ifp->flags;
1892 		struct in6_addr new_addr;
1893 		struct inet6_ifaddr *ifp2;
1894 		u32 valid_lft, preferred_lft;
1895 		int pfxlen = ifp->prefix_len;
1896 		int retries = ifp->stable_privacy_retry + 1;
1897 
1898 		if (retries > net->ipv6.sysctl.idgen_retries) {
1899 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
1900 					     ifp->idev->dev->name);
1901 			goto errdad;
1902 		}
1903 
1904 		new_addr = ifp->addr;
1905 		if (ipv6_generate_stable_address(&new_addr, retries,
1906 						 idev))
1907 			goto errdad;
1908 
1909 		valid_lft = ifp->valid_lft;
1910 		preferred_lft = ifp->prefered_lft;
1911 
1912 		spin_unlock_bh(&ifp->lock);
1913 
1914 		if (idev->cnf.max_addresses &&
1915 		    ipv6_count_addresses(idev) >=
1916 		    idev->cnf.max_addresses)
1917 			goto lock_errdad;
1918 
1919 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
1920 				     ifp->idev->dev->name);
1921 
1922 		ifp2 = ipv6_add_addr(idev, &new_addr, NULL, pfxlen,
1923 				     scope, flags, valid_lft,
1924 				     preferred_lft);
1925 		if (IS_ERR(ifp2))
1926 			goto lock_errdad;
1927 
1928 		spin_lock_bh(&ifp2->lock);
1929 		ifp2->stable_privacy_retry = retries;
1930 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
1931 		spin_unlock_bh(&ifp2->lock);
1932 
1933 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
1934 		in6_ifa_put(ifp2);
1935 lock_errdad:
1936 		spin_lock_bh(&ifp->lock);
1937 	} else if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1938 		addr.s6_addr32[0] = htonl(0xfe800000);
1939 		addr.s6_addr32[1] = 0;
1940 
1941 		if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1942 		    ipv6_addr_equal(&ifp->addr, &addr)) {
1943 			/* DAD failed for link-local based on MAC address */
1944 			idev->cnf.disable_ipv6 = 1;
1945 
1946 			pr_info("%s: IPv6 being disabled!\n",
1947 				ifp->idev->dev->name);
1948 		}
1949 	}
1950 
1951 errdad:
1952 	/* transition from _POSTDAD to _ERRDAD */
1953 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
1954 	spin_unlock_bh(&ifp->lock);
1955 
1956 	addrconf_mod_dad_work(ifp, 0);
1957 }
1958 
1959 /* Join to solicited addr multicast group.
1960  * caller must hold RTNL */
1961 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
1962 {
1963 	struct in6_addr maddr;
1964 
1965 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1966 		return;
1967 
1968 	addrconf_addr_solict_mult(addr, &maddr);
1969 	ipv6_dev_mc_inc(dev, &maddr);
1970 }
1971 
1972 /* caller must hold RTNL */
1973 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
1974 {
1975 	struct in6_addr maddr;
1976 
1977 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1978 		return;
1979 
1980 	addrconf_addr_solict_mult(addr, &maddr);
1981 	__ipv6_dev_mc_dec(idev, &maddr);
1982 }
1983 
1984 /* caller must hold RTNL */
1985 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1986 {
1987 	struct in6_addr addr;
1988 
1989 	if (ifp->prefix_len >= 127) /* RFC 6164 */
1990 		return;
1991 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1992 	if (ipv6_addr_any(&addr))
1993 		return;
1994 	__ipv6_dev_ac_inc(ifp->idev, &addr);
1995 }
1996 
1997 /* caller must hold RTNL */
1998 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1999 {
2000 	struct in6_addr addr;
2001 
2002 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2003 		return;
2004 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2005 	if (ipv6_addr_any(&addr))
2006 		return;
2007 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2008 }
2009 
2010 static int addrconf_ifid_eui64(u8 *eui, struct net_device *dev)
2011 {
2012 	if (dev->addr_len != EUI64_ADDR_LEN)
2013 		return -1;
2014 	memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2015 	eui[0] ^= 2;
2016 	return 0;
2017 }
2018 
2019 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2020 {
2021 	union fwnet_hwaddr *ha;
2022 
2023 	if (dev->addr_len != FWNET_ALEN)
2024 		return -1;
2025 
2026 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2027 
2028 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2029 	eui[0] ^= 2;
2030 	return 0;
2031 }
2032 
2033 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2034 {
2035 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2036 	if (dev->addr_len != ARCNET_ALEN)
2037 		return -1;
2038 	memset(eui, 0, 7);
2039 	eui[7] = *(u8 *)dev->dev_addr;
2040 	return 0;
2041 }
2042 
2043 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2044 {
2045 	if (dev->addr_len != INFINIBAND_ALEN)
2046 		return -1;
2047 	memcpy(eui, dev->dev_addr + 12, 8);
2048 	eui[0] |= 2;
2049 	return 0;
2050 }
2051 
2052 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2053 {
2054 	if (addr == 0)
2055 		return -1;
2056 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2057 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2058 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2059 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2060 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2061 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2062 	eui[1] = 0;
2063 	eui[2] = 0x5E;
2064 	eui[3] = 0xFE;
2065 	memcpy(eui + 4, &addr, 4);
2066 	return 0;
2067 }
2068 
2069 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2070 {
2071 	if (dev->priv_flags & IFF_ISATAP)
2072 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2073 	return -1;
2074 }
2075 
2076 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2077 {
2078 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2079 }
2080 
2081 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2082 {
2083 	memcpy(eui, dev->perm_addr, 3);
2084 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2085 	eui[3] = 0xFF;
2086 	eui[4] = 0xFE;
2087 	eui[0] ^= 2;
2088 	return 0;
2089 }
2090 
2091 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2092 {
2093 	switch (dev->type) {
2094 	case ARPHRD_ETHER:
2095 	case ARPHRD_FDDI:
2096 		return addrconf_ifid_eui48(eui, dev);
2097 	case ARPHRD_ARCNET:
2098 		return addrconf_ifid_arcnet(eui, dev);
2099 	case ARPHRD_INFINIBAND:
2100 		return addrconf_ifid_infiniband(eui, dev);
2101 	case ARPHRD_SIT:
2102 		return addrconf_ifid_sit(eui, dev);
2103 	case ARPHRD_IPGRE:
2104 		return addrconf_ifid_gre(eui, dev);
2105 	case ARPHRD_6LOWPAN:
2106 		return addrconf_ifid_eui64(eui, dev);
2107 	case ARPHRD_IEEE1394:
2108 		return addrconf_ifid_ieee1394(eui, dev);
2109 	case ARPHRD_TUNNEL6:
2110 		return addrconf_ifid_ip6tnl(eui, dev);
2111 	}
2112 	return -1;
2113 }
2114 
2115 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2116 {
2117 	int err = -1;
2118 	struct inet6_ifaddr *ifp;
2119 
2120 	read_lock_bh(&idev->lock);
2121 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2122 		if (ifp->scope > IFA_LINK)
2123 			break;
2124 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2125 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2126 			err = 0;
2127 			break;
2128 		}
2129 	}
2130 	read_unlock_bh(&idev->lock);
2131 	return err;
2132 }
2133 
2134 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2135 static void __ipv6_regen_rndid(struct inet6_dev *idev)
2136 {
2137 regen:
2138 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2139 	idev->rndid[0] &= ~0x02;
2140 
2141 	/*
2142 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2143 	 * check if generated address is not inappropriate
2144 	 *
2145 	 *  - Reserved subnet anycast (RFC 2526)
2146 	 *	11111101 11....11 1xxxxxxx
2147 	 *  - ISATAP (RFC4214) 6.1
2148 	 *	00-00-5E-FE-xx-xx-xx-xx
2149 	 *  - value 0
2150 	 *  - XXX: already assigned to an address on the device
2151 	 */
2152 	if (idev->rndid[0] == 0xfd &&
2153 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2154 	    (idev->rndid[7]&0x80))
2155 		goto regen;
2156 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2157 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2158 			goto regen;
2159 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2160 			goto regen;
2161 	}
2162 }
2163 
2164 static void ipv6_regen_rndid(unsigned long data)
2165 {
2166 	struct inet6_dev *idev = (struct inet6_dev *) data;
2167 	unsigned long expires;
2168 
2169 	rcu_read_lock_bh();
2170 	write_lock_bh(&idev->lock);
2171 
2172 	if (idev->dead)
2173 		goto out;
2174 
2175 	__ipv6_regen_rndid(idev);
2176 
2177 	expires = jiffies +
2178 		idev->cnf.temp_prefered_lft * HZ -
2179 		idev->cnf.regen_max_retry * idev->cnf.dad_transmits *
2180 		NEIGH_VAR(idev->nd_parms, RETRANS_TIME) -
2181 		idev->cnf.max_desync_factor * HZ;
2182 	if (time_before(expires, jiffies)) {
2183 		pr_warn("%s: too short regeneration interval; timer disabled for %s\n",
2184 			__func__, idev->dev->name);
2185 		goto out;
2186 	}
2187 
2188 	if (!mod_timer(&idev->regen_timer, expires))
2189 		in6_dev_hold(idev);
2190 
2191 out:
2192 	write_unlock_bh(&idev->lock);
2193 	rcu_read_unlock_bh();
2194 	in6_dev_put(idev);
2195 }
2196 
2197 static void  __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2198 {
2199 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2200 		__ipv6_regen_rndid(idev);
2201 }
2202 
2203 /*
2204  *	Add prefix route.
2205  */
2206 
2207 static void
2208 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
2209 		      unsigned long expires, u32 flags)
2210 {
2211 	struct fib6_config cfg = {
2212 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2213 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2214 		.fc_ifindex = dev->ifindex,
2215 		.fc_expires = expires,
2216 		.fc_dst_len = plen,
2217 		.fc_flags = RTF_UP | flags,
2218 		.fc_nlinfo.nl_net = dev_net(dev),
2219 		.fc_protocol = RTPROT_KERNEL,
2220 	};
2221 
2222 	cfg.fc_dst = *pfx;
2223 
2224 	/* Prevent useless cloning on PtP SIT.
2225 	   This thing is done here expecting that the whole
2226 	   class of non-broadcast devices need not cloning.
2227 	 */
2228 #if IS_ENABLED(CONFIG_IPV6_SIT)
2229 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2230 		cfg.fc_flags |= RTF_NONEXTHOP;
2231 #endif
2232 
2233 	ip6_route_add(&cfg);
2234 }
2235 
2236 
2237 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2238 						  int plen,
2239 						  const struct net_device *dev,
2240 						  u32 flags, u32 noflags)
2241 {
2242 	struct fib6_node *fn;
2243 	struct rt6_info *rt = NULL;
2244 	struct fib6_table *table;
2245 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2246 
2247 	table = fib6_get_table(dev_net(dev), tb_id);
2248 	if (!table)
2249 		return NULL;
2250 
2251 	read_lock_bh(&table->tb6_lock);
2252 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
2253 	if (!fn)
2254 		goto out;
2255 
2256 	noflags |= RTF_CACHE;
2257 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2258 		if (rt->dst.dev->ifindex != dev->ifindex)
2259 			continue;
2260 		if ((rt->rt6i_flags & flags) != flags)
2261 			continue;
2262 		if ((rt->rt6i_flags & noflags) != 0)
2263 			continue;
2264 		dst_hold(&rt->dst);
2265 		break;
2266 	}
2267 out:
2268 	read_unlock_bh(&table->tb6_lock);
2269 	return rt;
2270 }
2271 
2272 
2273 /* Create "default" multicast route to the interface */
2274 
2275 static void addrconf_add_mroute(struct net_device *dev)
2276 {
2277 	struct fib6_config cfg = {
2278 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2279 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2280 		.fc_ifindex = dev->ifindex,
2281 		.fc_dst_len = 8,
2282 		.fc_flags = RTF_UP,
2283 		.fc_nlinfo.nl_net = dev_net(dev),
2284 	};
2285 
2286 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2287 
2288 	ip6_route_add(&cfg);
2289 }
2290 
2291 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2292 {
2293 	struct inet6_dev *idev;
2294 
2295 	ASSERT_RTNL();
2296 
2297 	idev = ipv6_find_idev(dev);
2298 	if (!idev)
2299 		return ERR_PTR(-ENOBUFS);
2300 
2301 	if (idev->cnf.disable_ipv6)
2302 		return ERR_PTR(-EACCES);
2303 
2304 	/* Add default multicast route */
2305 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2306 		addrconf_add_mroute(dev);
2307 
2308 	return idev;
2309 }
2310 
2311 static void manage_tempaddrs(struct inet6_dev *idev,
2312 			     struct inet6_ifaddr *ifp,
2313 			     __u32 valid_lft, __u32 prefered_lft,
2314 			     bool create, unsigned long now)
2315 {
2316 	u32 flags;
2317 	struct inet6_ifaddr *ift;
2318 
2319 	read_lock_bh(&idev->lock);
2320 	/* update all temporary addresses in the list */
2321 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2322 		int age, max_valid, max_prefered;
2323 
2324 		if (ifp != ift->ifpub)
2325 			continue;
2326 
2327 		/* RFC 4941 section 3.3:
2328 		 * If a received option will extend the lifetime of a public
2329 		 * address, the lifetimes of temporary addresses should
2330 		 * be extended, subject to the overall constraint that no
2331 		 * temporary addresses should ever remain "valid" or "preferred"
2332 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2333 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2334 		 */
2335 		age = (now - ift->cstamp) / HZ;
2336 		max_valid = idev->cnf.temp_valid_lft - age;
2337 		if (max_valid < 0)
2338 			max_valid = 0;
2339 
2340 		max_prefered = idev->cnf.temp_prefered_lft -
2341 			       idev->cnf.max_desync_factor - age;
2342 		if (max_prefered < 0)
2343 			max_prefered = 0;
2344 
2345 		if (valid_lft > max_valid)
2346 			valid_lft = max_valid;
2347 
2348 		if (prefered_lft > max_prefered)
2349 			prefered_lft = max_prefered;
2350 
2351 		spin_lock(&ift->lock);
2352 		flags = ift->flags;
2353 		ift->valid_lft = valid_lft;
2354 		ift->prefered_lft = prefered_lft;
2355 		ift->tstamp = now;
2356 		if (prefered_lft > 0)
2357 			ift->flags &= ~IFA_F_DEPRECATED;
2358 
2359 		spin_unlock(&ift->lock);
2360 		if (!(flags&IFA_F_TENTATIVE))
2361 			ipv6_ifa_notify(0, ift);
2362 	}
2363 
2364 	if ((create || list_empty(&idev->tempaddr_list)) &&
2365 	    idev->cnf.use_tempaddr > 0) {
2366 		/* When a new public address is created as described
2367 		 * in [ADDRCONF], also create a new temporary address.
2368 		 * Also create a temporary address if it's enabled but
2369 		 * no temporary address currently exists.
2370 		 */
2371 		read_unlock_bh(&idev->lock);
2372 		ipv6_create_tempaddr(ifp, NULL);
2373 	} else {
2374 		read_unlock_bh(&idev->lock);
2375 	}
2376 }
2377 
2378 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2379 {
2380 	return idev->addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2381 	       idev->addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2382 }
2383 
2384 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2385 				 const struct prefix_info *pinfo,
2386 				 struct inet6_dev *in6_dev,
2387 				 const struct in6_addr *addr, int addr_type,
2388 				 u32 addr_flags, bool sllao, bool tokenized,
2389 				 __u32 valid_lft, u32 prefered_lft)
2390 {
2391 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2392 	int create = 0, update_lft = 0;
2393 
2394 	if (!ifp && valid_lft) {
2395 		int max_addresses = in6_dev->cnf.max_addresses;
2396 
2397 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2398 		if (in6_dev->cnf.optimistic_dad &&
2399 		    !net->ipv6.devconf_all->forwarding && sllao)
2400 			addr_flags |= IFA_F_OPTIMISTIC;
2401 #endif
2402 
2403 		/* Do not allow to create too much of autoconfigured
2404 		 * addresses; this would be too easy way to crash kernel.
2405 		 */
2406 		if (!max_addresses ||
2407 		    ipv6_count_addresses(in6_dev) < max_addresses)
2408 			ifp = ipv6_add_addr(in6_dev, addr, NULL,
2409 					    pinfo->prefix_len,
2410 					    addr_type&IPV6_ADDR_SCOPE_MASK,
2411 					    addr_flags, valid_lft,
2412 					    prefered_lft);
2413 
2414 		if (IS_ERR_OR_NULL(ifp))
2415 			return -1;
2416 
2417 		update_lft = 0;
2418 		create = 1;
2419 		spin_lock_bh(&ifp->lock);
2420 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2421 		ifp->cstamp = jiffies;
2422 		ifp->tokenized = tokenized;
2423 		spin_unlock_bh(&ifp->lock);
2424 		addrconf_dad_start(ifp);
2425 	}
2426 
2427 	if (ifp) {
2428 		u32 flags;
2429 		unsigned long now;
2430 		u32 stored_lft;
2431 
2432 		/* update lifetime (RFC2462 5.5.3 e) */
2433 		spin_lock_bh(&ifp->lock);
2434 		now = jiffies;
2435 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2436 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2437 		else
2438 			stored_lft = 0;
2439 		if (!update_lft && !create && stored_lft) {
2440 			const u32 minimum_lft = min_t(u32,
2441 				stored_lft, MIN_VALID_LIFETIME);
2442 			valid_lft = max(valid_lft, minimum_lft);
2443 
2444 			/* RFC4862 Section 5.5.3e:
2445 			 * "Note that the preferred lifetime of the
2446 			 *  corresponding address is always reset to
2447 			 *  the Preferred Lifetime in the received
2448 			 *  Prefix Information option, regardless of
2449 			 *  whether the valid lifetime is also reset or
2450 			 *  ignored."
2451 			 *
2452 			 * So we should always update prefered_lft here.
2453 			 */
2454 			update_lft = 1;
2455 		}
2456 
2457 		if (update_lft) {
2458 			ifp->valid_lft = valid_lft;
2459 			ifp->prefered_lft = prefered_lft;
2460 			ifp->tstamp = now;
2461 			flags = ifp->flags;
2462 			ifp->flags &= ~IFA_F_DEPRECATED;
2463 			spin_unlock_bh(&ifp->lock);
2464 
2465 			if (!(flags&IFA_F_TENTATIVE))
2466 				ipv6_ifa_notify(0, ifp);
2467 		} else
2468 			spin_unlock_bh(&ifp->lock);
2469 
2470 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2471 				 create, now);
2472 
2473 		in6_ifa_put(ifp);
2474 		addrconf_verify();
2475 	}
2476 
2477 	return 0;
2478 }
2479 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2480 
2481 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2482 {
2483 	struct prefix_info *pinfo;
2484 	__u32 valid_lft;
2485 	__u32 prefered_lft;
2486 	int addr_type, err;
2487 	u32 addr_flags = 0;
2488 	struct inet6_dev *in6_dev;
2489 	struct net *net = dev_net(dev);
2490 
2491 	pinfo = (struct prefix_info *) opt;
2492 
2493 	if (len < sizeof(struct prefix_info)) {
2494 		ADBG("addrconf: prefix option too short\n");
2495 		return;
2496 	}
2497 
2498 	/*
2499 	 *	Validation checks ([ADDRCONF], page 19)
2500 	 */
2501 
2502 	addr_type = ipv6_addr_type(&pinfo->prefix);
2503 
2504 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2505 		return;
2506 
2507 	valid_lft = ntohl(pinfo->valid);
2508 	prefered_lft = ntohl(pinfo->prefered);
2509 
2510 	if (prefered_lft > valid_lft) {
2511 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2512 		return;
2513 	}
2514 
2515 	in6_dev = in6_dev_get(dev);
2516 
2517 	if (!in6_dev) {
2518 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2519 				    dev->name);
2520 		return;
2521 	}
2522 
2523 	/*
2524 	 *	Two things going on here:
2525 	 *	1) Add routes for on-link prefixes
2526 	 *	2) Configure prefixes with the auto flag set
2527 	 */
2528 
2529 	if (pinfo->onlink) {
2530 		struct rt6_info *rt;
2531 		unsigned long rt_expires;
2532 
2533 		/* Avoid arithmetic overflow. Really, we could
2534 		 * save rt_expires in seconds, likely valid_lft,
2535 		 * but it would require division in fib gc, that it
2536 		 * not good.
2537 		 */
2538 		if (HZ > USER_HZ)
2539 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2540 		else
2541 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2542 
2543 		if (addrconf_finite_timeout(rt_expires))
2544 			rt_expires *= HZ;
2545 
2546 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2547 					       pinfo->prefix_len,
2548 					       dev,
2549 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2550 					       RTF_GATEWAY | RTF_DEFAULT);
2551 
2552 		if (rt) {
2553 			/* Autoconf prefix route */
2554 			if (valid_lft == 0) {
2555 				ip6_del_rt(rt);
2556 				rt = NULL;
2557 			} else if (addrconf_finite_timeout(rt_expires)) {
2558 				/* not infinity */
2559 				rt6_set_expires(rt, jiffies + rt_expires);
2560 			} else {
2561 				rt6_clean_expires(rt);
2562 			}
2563 		} else if (valid_lft) {
2564 			clock_t expires = 0;
2565 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2566 			if (addrconf_finite_timeout(rt_expires)) {
2567 				/* not infinity */
2568 				flags |= RTF_EXPIRES;
2569 				expires = jiffies_to_clock_t(rt_expires);
2570 			}
2571 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2572 					      dev, expires, flags);
2573 		}
2574 		ip6_rt_put(rt);
2575 	}
2576 
2577 	/* Try to figure out our local address for this prefix */
2578 
2579 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2580 		struct in6_addr addr;
2581 		bool tokenized = false, dev_addr_generated = false;
2582 
2583 		if (pinfo->prefix_len == 64) {
2584 			memcpy(&addr, &pinfo->prefix, 8);
2585 
2586 			if (!ipv6_addr_any(&in6_dev->token)) {
2587 				read_lock_bh(&in6_dev->lock);
2588 				memcpy(addr.s6_addr + 8,
2589 				       in6_dev->token.s6_addr + 8, 8);
2590 				read_unlock_bh(&in6_dev->lock);
2591 				tokenized = true;
2592 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2593 				   !ipv6_generate_stable_address(&addr, 0,
2594 								 in6_dev)) {
2595 				addr_flags |= IFA_F_STABLE_PRIVACY;
2596 				goto ok;
2597 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2598 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2599 				goto put;
2600 			} else {
2601 				dev_addr_generated = true;
2602 			}
2603 			goto ok;
2604 		}
2605 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2606 				    pinfo->prefix_len);
2607 		goto put;
2608 
2609 ok:
2610 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2611 						   &addr, addr_type,
2612 						   addr_flags, sllao,
2613 						   tokenized, valid_lft,
2614 						   prefered_lft);
2615 		if (err)
2616 			goto put;
2617 
2618 		/* Ignore error case here because previous prefix add addr was
2619 		 * successful which will be notified.
2620 		 */
2621 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2622 					      addr_type, addr_flags, sllao,
2623 					      tokenized, valid_lft,
2624 					      prefered_lft,
2625 					      dev_addr_generated);
2626 	}
2627 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2628 put:
2629 	in6_dev_put(in6_dev);
2630 }
2631 
2632 /*
2633  *	Set destination address.
2634  *	Special case for SIT interfaces where we create a new "virtual"
2635  *	device.
2636  */
2637 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2638 {
2639 	struct in6_ifreq ireq;
2640 	struct net_device *dev;
2641 	int err = -EINVAL;
2642 
2643 	rtnl_lock();
2644 
2645 	err = -EFAULT;
2646 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2647 		goto err_exit;
2648 
2649 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2650 
2651 	err = -ENODEV;
2652 	if (!dev)
2653 		goto err_exit;
2654 
2655 #if IS_ENABLED(CONFIG_IPV6_SIT)
2656 	if (dev->type == ARPHRD_SIT) {
2657 		const struct net_device_ops *ops = dev->netdev_ops;
2658 		struct ifreq ifr;
2659 		struct ip_tunnel_parm p;
2660 
2661 		err = -EADDRNOTAVAIL;
2662 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2663 			goto err_exit;
2664 
2665 		memset(&p, 0, sizeof(p));
2666 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2667 		p.iph.saddr = 0;
2668 		p.iph.version = 4;
2669 		p.iph.ihl = 5;
2670 		p.iph.protocol = IPPROTO_IPV6;
2671 		p.iph.ttl = 64;
2672 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2673 
2674 		if (ops->ndo_do_ioctl) {
2675 			mm_segment_t oldfs = get_fs();
2676 
2677 			set_fs(KERNEL_DS);
2678 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2679 			set_fs(oldfs);
2680 		} else
2681 			err = -EOPNOTSUPP;
2682 
2683 		if (err == 0) {
2684 			err = -ENOBUFS;
2685 			dev = __dev_get_by_name(net, p.name);
2686 			if (!dev)
2687 				goto err_exit;
2688 			err = dev_open(dev);
2689 		}
2690 	}
2691 #endif
2692 
2693 err_exit:
2694 	rtnl_unlock();
2695 	return err;
2696 }
2697 
2698 static int ipv6_mc_config(struct sock *sk, bool join,
2699 			  const struct in6_addr *addr, int ifindex)
2700 {
2701 	int ret;
2702 
2703 	ASSERT_RTNL();
2704 
2705 	lock_sock(sk);
2706 	if (join)
2707 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2708 	else
2709 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2710 	release_sock(sk);
2711 
2712 	return ret;
2713 }
2714 
2715 /*
2716  *	Manual configuration of address on an interface
2717  */
2718 static int inet6_addr_add(struct net *net, int ifindex,
2719 			  const struct in6_addr *pfx,
2720 			  const struct in6_addr *peer_pfx,
2721 			  unsigned int plen, __u32 ifa_flags,
2722 			  __u32 prefered_lft, __u32 valid_lft)
2723 {
2724 	struct inet6_ifaddr *ifp;
2725 	struct inet6_dev *idev;
2726 	struct net_device *dev;
2727 	unsigned long timeout;
2728 	clock_t expires;
2729 	int scope;
2730 	u32 flags;
2731 
2732 	ASSERT_RTNL();
2733 
2734 	if (plen > 128)
2735 		return -EINVAL;
2736 
2737 	/* check the lifetime */
2738 	if (!valid_lft || prefered_lft > valid_lft)
2739 		return -EINVAL;
2740 
2741 	if (ifa_flags & IFA_F_MANAGETEMPADDR && plen != 64)
2742 		return -EINVAL;
2743 
2744 	dev = __dev_get_by_index(net, ifindex);
2745 	if (!dev)
2746 		return -ENODEV;
2747 
2748 	idev = addrconf_add_dev(dev);
2749 	if (IS_ERR(idev))
2750 		return PTR_ERR(idev);
2751 
2752 	if (ifa_flags & IFA_F_MCAUTOJOIN) {
2753 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2754 					 true, pfx, ifindex);
2755 
2756 		if (ret < 0)
2757 			return ret;
2758 	}
2759 
2760 	scope = ipv6_addr_scope(pfx);
2761 
2762 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2763 	if (addrconf_finite_timeout(timeout)) {
2764 		expires = jiffies_to_clock_t(timeout * HZ);
2765 		valid_lft = timeout;
2766 		flags = RTF_EXPIRES;
2767 	} else {
2768 		expires = 0;
2769 		flags = 0;
2770 		ifa_flags |= IFA_F_PERMANENT;
2771 	}
2772 
2773 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2774 	if (addrconf_finite_timeout(timeout)) {
2775 		if (timeout == 0)
2776 			ifa_flags |= IFA_F_DEPRECATED;
2777 		prefered_lft = timeout;
2778 	}
2779 
2780 	ifp = ipv6_add_addr(idev, pfx, peer_pfx, plen, scope, ifa_flags,
2781 			    valid_lft, prefered_lft);
2782 
2783 	if (!IS_ERR(ifp)) {
2784 		if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
2785 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2786 					      expires, flags);
2787 		}
2788 
2789 		/*
2790 		 * Note that section 3.1 of RFC 4429 indicates
2791 		 * that the Optimistic flag should not be set for
2792 		 * manually configured addresses
2793 		 */
2794 		addrconf_dad_start(ifp);
2795 		if (ifa_flags & IFA_F_MANAGETEMPADDR)
2796 			manage_tempaddrs(idev, ifp, valid_lft, prefered_lft,
2797 					 true, jiffies);
2798 		in6_ifa_put(ifp);
2799 		addrconf_verify_rtnl();
2800 		return 0;
2801 	} else if (ifa_flags & IFA_F_MCAUTOJOIN) {
2802 		ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2803 			       false, pfx, ifindex);
2804 	}
2805 
2806 	return PTR_ERR(ifp);
2807 }
2808 
2809 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2810 			  const struct in6_addr *pfx, unsigned int plen)
2811 {
2812 	struct inet6_ifaddr *ifp;
2813 	struct inet6_dev *idev;
2814 	struct net_device *dev;
2815 
2816 	if (plen > 128)
2817 		return -EINVAL;
2818 
2819 	dev = __dev_get_by_index(net, ifindex);
2820 	if (!dev)
2821 		return -ENODEV;
2822 
2823 	idev = __in6_dev_get(dev);
2824 	if (!idev)
2825 		return -ENXIO;
2826 
2827 	read_lock_bh(&idev->lock);
2828 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2829 		if (ifp->prefix_len == plen &&
2830 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2831 			in6_ifa_hold(ifp);
2832 			read_unlock_bh(&idev->lock);
2833 
2834 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
2835 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
2836 				manage_tempaddrs(idev, ifp, 0, 0, false,
2837 						 jiffies);
2838 			ipv6_del_addr(ifp);
2839 			addrconf_verify_rtnl();
2840 			if (ipv6_addr_is_multicast(pfx)) {
2841 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2842 					       false, pfx, dev->ifindex);
2843 			}
2844 			return 0;
2845 		}
2846 	}
2847 	read_unlock_bh(&idev->lock);
2848 	return -EADDRNOTAVAIL;
2849 }
2850 
2851 
2852 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2853 {
2854 	struct in6_ifreq ireq;
2855 	int err;
2856 
2857 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2858 		return -EPERM;
2859 
2860 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2861 		return -EFAULT;
2862 
2863 	rtnl_lock();
2864 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr, NULL,
2865 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2866 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2867 	rtnl_unlock();
2868 	return err;
2869 }
2870 
2871 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2872 {
2873 	struct in6_ifreq ireq;
2874 	int err;
2875 
2876 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2877 		return -EPERM;
2878 
2879 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2880 		return -EFAULT;
2881 
2882 	rtnl_lock();
2883 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
2884 			     ireq.ifr6_prefixlen);
2885 	rtnl_unlock();
2886 	return err;
2887 }
2888 
2889 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2890 		     int plen, int scope)
2891 {
2892 	struct inet6_ifaddr *ifp;
2893 
2894 	ifp = ipv6_add_addr(idev, addr, NULL, plen,
2895 			    scope, IFA_F_PERMANENT,
2896 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2897 	if (!IS_ERR(ifp)) {
2898 		spin_lock_bh(&ifp->lock);
2899 		ifp->flags &= ~IFA_F_TENTATIVE;
2900 		spin_unlock_bh(&ifp->lock);
2901 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2902 		in6_ifa_put(ifp);
2903 	}
2904 }
2905 
2906 #if IS_ENABLED(CONFIG_IPV6_SIT)
2907 static void sit_add_v4_addrs(struct inet6_dev *idev)
2908 {
2909 	struct in6_addr addr;
2910 	struct net_device *dev;
2911 	struct net *net = dev_net(idev->dev);
2912 	int scope, plen;
2913 	u32 pflags = 0;
2914 
2915 	ASSERT_RTNL();
2916 
2917 	memset(&addr, 0, sizeof(struct in6_addr));
2918 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2919 
2920 	if (idev->dev->flags&IFF_POINTOPOINT) {
2921 		addr.s6_addr32[0] = htonl(0xfe800000);
2922 		scope = IFA_LINK;
2923 		plen = 64;
2924 	} else {
2925 		scope = IPV6_ADDR_COMPATv4;
2926 		plen = 96;
2927 		pflags |= RTF_NONEXTHOP;
2928 	}
2929 
2930 	if (addr.s6_addr32[3]) {
2931 		add_addr(idev, &addr, plen, scope);
2932 		addrconf_prefix_route(&addr, plen, idev->dev, 0, pflags);
2933 		return;
2934 	}
2935 
2936 	for_each_netdev(net, dev) {
2937 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
2938 		if (in_dev && (dev->flags & IFF_UP)) {
2939 			struct in_ifaddr *ifa;
2940 
2941 			int flag = scope;
2942 
2943 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2944 
2945 				addr.s6_addr32[3] = ifa->ifa_local;
2946 
2947 				if (ifa->ifa_scope == RT_SCOPE_LINK)
2948 					continue;
2949 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2950 					if (idev->dev->flags&IFF_POINTOPOINT)
2951 						continue;
2952 					flag |= IFA_HOST;
2953 				}
2954 
2955 				add_addr(idev, &addr, plen, flag);
2956 				addrconf_prefix_route(&addr, plen, idev->dev, 0,
2957 						      pflags);
2958 			}
2959 		}
2960 	}
2961 }
2962 #endif
2963 
2964 static void init_loopback(struct net_device *dev)
2965 {
2966 	struct inet6_dev  *idev;
2967 	struct net_device *sp_dev;
2968 	struct inet6_ifaddr *sp_ifa;
2969 	struct rt6_info *sp_rt;
2970 
2971 	/* ::1 */
2972 
2973 	ASSERT_RTNL();
2974 
2975 	idev = ipv6_find_idev(dev);
2976 	if (!idev) {
2977 		pr_debug("%s: add_dev failed\n", __func__);
2978 		return;
2979 	}
2980 
2981 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2982 
2983 	/* Add routes to other interface's IPv6 addresses */
2984 	for_each_netdev(dev_net(dev), sp_dev) {
2985 		if (!strcmp(sp_dev->name, dev->name))
2986 			continue;
2987 
2988 		idev = __in6_dev_get(sp_dev);
2989 		if (!idev)
2990 			continue;
2991 
2992 		read_lock_bh(&idev->lock);
2993 		list_for_each_entry(sp_ifa, &idev->addr_list, if_list) {
2994 
2995 			if (sp_ifa->flags & (IFA_F_DADFAILED | IFA_F_TENTATIVE))
2996 				continue;
2997 
2998 			if (sp_ifa->rt) {
2999 				/* This dst has been added to garbage list when
3000 				 * lo device down, release this obsolete dst and
3001 				 * reallocate a new router for ifa.
3002 				 */
3003 				if (sp_ifa->rt->dst.obsolete > 0) {
3004 					ip6_rt_put(sp_ifa->rt);
3005 					sp_ifa->rt = NULL;
3006 				} else {
3007 					continue;
3008 				}
3009 			}
3010 
3011 			sp_rt = addrconf_dst_alloc(idev, &sp_ifa->addr, false);
3012 
3013 			/* Failure cases are ignored */
3014 			if (!IS_ERR(sp_rt)) {
3015 				sp_ifa->rt = sp_rt;
3016 				ip6_ins_rt(sp_rt);
3017 			}
3018 		}
3019 		read_unlock_bh(&idev->lock);
3020 	}
3021 }
3022 
3023 void addrconf_add_linklocal(struct inet6_dev *idev,
3024 			    const struct in6_addr *addr, u32 flags)
3025 {
3026 	struct inet6_ifaddr *ifp;
3027 	u32 addr_flags = flags | IFA_F_PERMANENT;
3028 
3029 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3030 	if (idev->cnf.optimistic_dad &&
3031 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3032 		addr_flags |= IFA_F_OPTIMISTIC;
3033 #endif
3034 
3035 	ifp = ipv6_add_addr(idev, addr, NULL, 64, IFA_LINK, addr_flags,
3036 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
3037 	if (!IS_ERR(ifp)) {
3038 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
3039 		addrconf_dad_start(ifp);
3040 		in6_ifa_put(ifp);
3041 	}
3042 }
3043 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3044 
3045 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3046 {
3047 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3048 		return true;
3049 
3050 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3051 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3052 		return true;
3053 
3054 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3055 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3056 		return true;
3057 
3058 	return false;
3059 }
3060 
3061 static int ipv6_generate_stable_address(struct in6_addr *address,
3062 					u8 dad_count,
3063 					const struct inet6_dev *idev)
3064 {
3065 	static DEFINE_SPINLOCK(lock);
3066 	static __u32 digest[SHA_DIGEST_WORDS];
3067 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3068 
3069 	static union {
3070 		char __data[SHA_MESSAGE_BYTES];
3071 		struct {
3072 			struct in6_addr secret;
3073 			__be32 prefix[2];
3074 			unsigned char hwaddr[MAX_ADDR_LEN];
3075 			u8 dad_count;
3076 		} __packed;
3077 	} data;
3078 
3079 	struct in6_addr secret;
3080 	struct in6_addr temp;
3081 	struct net *net = dev_net(idev->dev);
3082 
3083 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3084 
3085 	if (idev->cnf.stable_secret.initialized)
3086 		secret = idev->cnf.stable_secret.secret;
3087 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3088 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3089 	else
3090 		return -1;
3091 
3092 retry:
3093 	spin_lock_bh(&lock);
3094 
3095 	sha_init(digest);
3096 	memset(&data, 0, sizeof(data));
3097 	memset(workspace, 0, sizeof(workspace));
3098 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3099 	data.prefix[0] = address->s6_addr32[0];
3100 	data.prefix[1] = address->s6_addr32[1];
3101 	data.secret = secret;
3102 	data.dad_count = dad_count;
3103 
3104 	sha_transform(digest, data.__data, workspace);
3105 
3106 	temp = *address;
3107 	temp.s6_addr32[2] = (__force __be32)digest[0];
3108 	temp.s6_addr32[3] = (__force __be32)digest[1];
3109 
3110 	spin_unlock_bh(&lock);
3111 
3112 	if (ipv6_reserved_interfaceid(temp)) {
3113 		dad_count++;
3114 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3115 			return -1;
3116 		goto retry;
3117 	}
3118 
3119 	*address = temp;
3120 	return 0;
3121 }
3122 
3123 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3124 {
3125 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3126 
3127 	if (s->initialized)
3128 		return;
3129 	s = &idev->cnf.stable_secret;
3130 	get_random_bytes(&s->secret, sizeof(s->secret));
3131 	s->initialized = true;
3132 }
3133 
3134 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3135 {
3136 	struct in6_addr addr;
3137 
3138 	/* no link local addresses on L3 master devices */
3139 	if (netif_is_l3_master(idev->dev))
3140 		return;
3141 
3142 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3143 
3144 	switch (idev->addr_gen_mode) {
3145 	case IN6_ADDR_GEN_MODE_RANDOM:
3146 		ipv6_gen_mode_random_init(idev);
3147 		/* fallthrough */
3148 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3149 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3150 			addrconf_add_linklocal(idev, &addr,
3151 					       IFA_F_STABLE_PRIVACY);
3152 		else if (prefix_route)
3153 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
3154 		break;
3155 	case IN6_ADDR_GEN_MODE_EUI64:
3156 		/* addrconf_add_linklocal also adds a prefix_route and we
3157 		 * only need to care about prefix routes if ipv6_generate_eui64
3158 		 * couldn't generate one.
3159 		 */
3160 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3161 			addrconf_add_linklocal(idev, &addr, 0);
3162 		else if (prefix_route)
3163 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
3164 		break;
3165 	case IN6_ADDR_GEN_MODE_NONE:
3166 	default:
3167 		/* will not add any link local address */
3168 		break;
3169 	}
3170 }
3171 
3172 static void addrconf_dev_config(struct net_device *dev)
3173 {
3174 	struct inet6_dev *idev;
3175 
3176 	ASSERT_RTNL();
3177 
3178 	if ((dev->type != ARPHRD_ETHER) &&
3179 	    (dev->type != ARPHRD_FDDI) &&
3180 	    (dev->type != ARPHRD_ARCNET) &&
3181 	    (dev->type != ARPHRD_INFINIBAND) &&
3182 	    (dev->type != ARPHRD_IEEE1394) &&
3183 	    (dev->type != ARPHRD_TUNNEL6) &&
3184 	    (dev->type != ARPHRD_6LOWPAN) &&
3185 	    (dev->type != ARPHRD_NONE)) {
3186 		/* Alas, we support only Ethernet autoconfiguration. */
3187 		return;
3188 	}
3189 
3190 	idev = addrconf_add_dev(dev);
3191 	if (IS_ERR(idev))
3192 		return;
3193 
3194 	/* this device type has no EUI support */
3195 	if (dev->type == ARPHRD_NONE &&
3196 	    idev->addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3197 		idev->addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3198 
3199 	addrconf_addr_gen(idev, false);
3200 }
3201 
3202 #if IS_ENABLED(CONFIG_IPV6_SIT)
3203 static void addrconf_sit_config(struct net_device *dev)
3204 {
3205 	struct inet6_dev *idev;
3206 
3207 	ASSERT_RTNL();
3208 
3209 	/*
3210 	 * Configure the tunnel with one of our IPv4
3211 	 * addresses... we should configure all of
3212 	 * our v4 addrs in the tunnel
3213 	 */
3214 
3215 	idev = ipv6_find_idev(dev);
3216 	if (!idev) {
3217 		pr_debug("%s: add_dev failed\n", __func__);
3218 		return;
3219 	}
3220 
3221 	if (dev->priv_flags & IFF_ISATAP) {
3222 		addrconf_addr_gen(idev, false);
3223 		return;
3224 	}
3225 
3226 	sit_add_v4_addrs(idev);
3227 
3228 	if (dev->flags&IFF_POINTOPOINT)
3229 		addrconf_add_mroute(dev);
3230 }
3231 #endif
3232 
3233 #if IS_ENABLED(CONFIG_NET_IPGRE)
3234 static void addrconf_gre_config(struct net_device *dev)
3235 {
3236 	struct inet6_dev *idev;
3237 
3238 	ASSERT_RTNL();
3239 
3240 	idev = ipv6_find_idev(dev);
3241 	if (!idev) {
3242 		pr_debug("%s: add_dev failed\n", __func__);
3243 		return;
3244 	}
3245 
3246 	addrconf_addr_gen(idev, true);
3247 	if (dev->flags & IFF_POINTOPOINT)
3248 		addrconf_add_mroute(dev);
3249 }
3250 #endif
3251 
3252 static int fixup_permanent_addr(struct inet6_dev *idev,
3253 				struct inet6_ifaddr *ifp)
3254 {
3255 	if (!ifp->rt) {
3256 		struct rt6_info *rt;
3257 
3258 		rt = addrconf_dst_alloc(idev, &ifp->addr, false);
3259 		if (unlikely(IS_ERR(rt)))
3260 			return PTR_ERR(rt);
3261 
3262 		ifp->rt = rt;
3263 	}
3264 
3265 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3266 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3267 				      idev->dev, 0, 0);
3268 	}
3269 
3270 	addrconf_dad_start(ifp);
3271 
3272 	return 0;
3273 }
3274 
3275 static void addrconf_permanent_addr(struct net_device *dev)
3276 {
3277 	struct inet6_ifaddr *ifp, *tmp;
3278 	struct inet6_dev *idev;
3279 
3280 	idev = __in6_dev_get(dev);
3281 	if (!idev)
3282 		return;
3283 
3284 	write_lock_bh(&idev->lock);
3285 
3286 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3287 		if ((ifp->flags & IFA_F_PERMANENT) &&
3288 		    fixup_permanent_addr(idev, ifp) < 0) {
3289 			write_unlock_bh(&idev->lock);
3290 			ipv6_del_addr(ifp);
3291 			write_lock_bh(&idev->lock);
3292 
3293 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3294 					     idev->dev->name, &ifp->addr);
3295 		}
3296 	}
3297 
3298 	write_unlock_bh(&idev->lock);
3299 }
3300 
3301 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3302 			   void *ptr)
3303 {
3304 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3305 	struct netdev_notifier_changeupper_info *info;
3306 	struct inet6_dev *idev = __in6_dev_get(dev);
3307 	int run_pending = 0;
3308 	int err;
3309 
3310 	switch (event) {
3311 	case NETDEV_REGISTER:
3312 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3313 			idev = ipv6_add_dev(dev);
3314 			if (IS_ERR(idev))
3315 				return notifier_from_errno(PTR_ERR(idev));
3316 		}
3317 		break;
3318 
3319 	case NETDEV_CHANGEMTU:
3320 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3321 		if (dev->mtu < IPV6_MIN_MTU) {
3322 			addrconf_ifdown(dev, 1);
3323 			break;
3324 		}
3325 
3326 		if (idev) {
3327 			rt6_mtu_change(dev, dev->mtu);
3328 			idev->cnf.mtu6 = dev->mtu;
3329 			break;
3330 		}
3331 
3332 		/* allocate new idev */
3333 		idev = ipv6_add_dev(dev);
3334 		if (IS_ERR(idev))
3335 			break;
3336 
3337 		/* device is still not ready */
3338 		if (!(idev->if_flags & IF_READY))
3339 			break;
3340 
3341 		run_pending = 1;
3342 
3343 		/* fall through */
3344 
3345 	case NETDEV_UP:
3346 	case NETDEV_CHANGE:
3347 		if (dev->flags & IFF_SLAVE)
3348 			break;
3349 
3350 		if (idev && idev->cnf.disable_ipv6)
3351 			break;
3352 
3353 		if (event == NETDEV_UP) {
3354 			/* restore routes for permanent addresses */
3355 			addrconf_permanent_addr(dev);
3356 
3357 			if (!addrconf_qdisc_ok(dev)) {
3358 				/* device is not ready yet. */
3359 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3360 					dev->name);
3361 				break;
3362 			}
3363 
3364 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3365 				idev = ipv6_add_dev(dev);
3366 
3367 			if (!IS_ERR_OR_NULL(idev)) {
3368 				idev->if_flags |= IF_READY;
3369 				run_pending = 1;
3370 			}
3371 		} else if (event == NETDEV_CHANGE) {
3372 			if (!addrconf_qdisc_ok(dev)) {
3373 				/* device is still not ready. */
3374 				break;
3375 			}
3376 
3377 			if (idev) {
3378 				if (idev->if_flags & IF_READY)
3379 					/* device is already configured. */
3380 					break;
3381 				idev->if_flags |= IF_READY;
3382 			}
3383 
3384 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3385 				dev->name);
3386 
3387 			run_pending = 1;
3388 		}
3389 
3390 		switch (dev->type) {
3391 #if IS_ENABLED(CONFIG_IPV6_SIT)
3392 		case ARPHRD_SIT:
3393 			addrconf_sit_config(dev);
3394 			break;
3395 #endif
3396 #if IS_ENABLED(CONFIG_NET_IPGRE)
3397 		case ARPHRD_IPGRE:
3398 			addrconf_gre_config(dev);
3399 			break;
3400 #endif
3401 		case ARPHRD_LOOPBACK:
3402 			init_loopback(dev);
3403 			break;
3404 
3405 		default:
3406 			addrconf_dev_config(dev);
3407 			break;
3408 		}
3409 
3410 		if (!IS_ERR_OR_NULL(idev)) {
3411 			if (run_pending)
3412 				addrconf_dad_run(idev);
3413 
3414 			/*
3415 			 * If the MTU changed during the interface down,
3416 			 * when the interface up, the changed MTU must be
3417 			 * reflected in the idev as well as routers.
3418 			 */
3419 			if (idev->cnf.mtu6 != dev->mtu &&
3420 			    dev->mtu >= IPV6_MIN_MTU) {
3421 				rt6_mtu_change(dev, dev->mtu);
3422 				idev->cnf.mtu6 = dev->mtu;
3423 			}
3424 			idev->tstamp = jiffies;
3425 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3426 
3427 			/*
3428 			 * If the changed mtu during down is lower than
3429 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3430 			 */
3431 			if (dev->mtu < IPV6_MIN_MTU)
3432 				addrconf_ifdown(dev, 1);
3433 		}
3434 		break;
3435 
3436 	case NETDEV_DOWN:
3437 	case NETDEV_UNREGISTER:
3438 		/*
3439 		 *	Remove all addresses from this interface.
3440 		 */
3441 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3442 		break;
3443 
3444 	case NETDEV_CHANGENAME:
3445 		if (idev) {
3446 			snmp6_unregister_dev(idev);
3447 			addrconf_sysctl_unregister(idev);
3448 			err = addrconf_sysctl_register(idev);
3449 			if (err)
3450 				return notifier_from_errno(err);
3451 			err = snmp6_register_dev(idev);
3452 			if (err) {
3453 				addrconf_sysctl_unregister(idev);
3454 				return notifier_from_errno(err);
3455 			}
3456 		}
3457 		break;
3458 
3459 	case NETDEV_PRE_TYPE_CHANGE:
3460 	case NETDEV_POST_TYPE_CHANGE:
3461 		if (idev)
3462 			addrconf_type_change(dev, event);
3463 		break;
3464 
3465 	case NETDEV_CHANGEUPPER:
3466 		info = ptr;
3467 
3468 		/* flush all routes if dev is linked to or unlinked from
3469 		 * an L3 master device (e.g., VRF)
3470 		 */
3471 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3472 			addrconf_ifdown(dev, 0);
3473 	}
3474 
3475 	return NOTIFY_OK;
3476 }
3477 
3478 /*
3479  *	addrconf module should be notified of a device going up
3480  */
3481 static struct notifier_block ipv6_dev_notf = {
3482 	.notifier_call = addrconf_notify,
3483 };
3484 
3485 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3486 {
3487 	struct inet6_dev *idev;
3488 	ASSERT_RTNL();
3489 
3490 	idev = __in6_dev_get(dev);
3491 
3492 	if (event == NETDEV_POST_TYPE_CHANGE)
3493 		ipv6_mc_remap(idev);
3494 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3495 		ipv6_mc_unmap(idev);
3496 }
3497 
3498 static bool addr_is_local(const struct in6_addr *addr)
3499 {
3500 	return ipv6_addr_type(addr) &
3501 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3502 }
3503 
3504 static int addrconf_ifdown(struct net_device *dev, int how)
3505 {
3506 	struct net *net = dev_net(dev);
3507 	struct inet6_dev *idev;
3508 	struct inet6_ifaddr *ifa, *tmp;
3509 	struct list_head del_list;
3510 	int _keep_addr;
3511 	bool keep_addr;
3512 	int state, i;
3513 
3514 	ASSERT_RTNL();
3515 
3516 	rt6_ifdown(net, dev);
3517 	neigh_ifdown(&nd_tbl, dev);
3518 
3519 	idev = __in6_dev_get(dev);
3520 	if (!idev)
3521 		return -ENODEV;
3522 
3523 	/*
3524 	 * Step 1: remove reference to ipv6 device from parent device.
3525 	 *	   Do not dev_put!
3526 	 */
3527 	if (how) {
3528 		idev->dead = 1;
3529 
3530 		/* protected by rtnl_lock */
3531 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3532 
3533 		/* Step 1.5: remove snmp6 entry */
3534 		snmp6_unregister_dev(idev);
3535 
3536 	}
3537 
3538 	/* aggregate the system setting and interface setting */
3539 	_keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3540 	if (!_keep_addr)
3541 		_keep_addr = idev->cnf.keep_addr_on_down;
3542 
3543 	/* combine the user config with event to determine if permanent
3544 	 * addresses are to be removed from address hash table
3545 	 */
3546 	keep_addr = !(how || _keep_addr <= 0);
3547 
3548 	/* Step 2: clear hash table */
3549 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3550 		struct hlist_head *h = &inet6_addr_lst[i];
3551 
3552 		spin_lock_bh(&addrconf_hash_lock);
3553 restart:
3554 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3555 			if (ifa->idev == idev) {
3556 				addrconf_del_dad_work(ifa);
3557 				/* combined flag + permanent flag decide if
3558 				 * address is retained on a down event
3559 				 */
3560 				if (!keep_addr ||
3561 				    !(ifa->flags & IFA_F_PERMANENT) ||
3562 				    addr_is_local(&ifa->addr)) {
3563 					hlist_del_init_rcu(&ifa->addr_lst);
3564 					goto restart;
3565 				}
3566 			}
3567 		}
3568 		spin_unlock_bh(&addrconf_hash_lock);
3569 	}
3570 
3571 	write_lock_bh(&idev->lock);
3572 
3573 	addrconf_del_rs_timer(idev);
3574 
3575 	/* Step 2: clear flags for stateless addrconf */
3576 	if (!how)
3577 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3578 
3579 	if (how && del_timer(&idev->regen_timer))
3580 		in6_dev_put(idev);
3581 
3582 	/* Step 3: clear tempaddr list */
3583 	while (!list_empty(&idev->tempaddr_list)) {
3584 		ifa = list_first_entry(&idev->tempaddr_list,
3585 				       struct inet6_ifaddr, tmp_list);
3586 		list_del(&ifa->tmp_list);
3587 		write_unlock_bh(&idev->lock);
3588 		spin_lock_bh(&ifa->lock);
3589 
3590 		if (ifa->ifpub) {
3591 			in6_ifa_put(ifa->ifpub);
3592 			ifa->ifpub = NULL;
3593 		}
3594 		spin_unlock_bh(&ifa->lock);
3595 		in6_ifa_put(ifa);
3596 		write_lock_bh(&idev->lock);
3597 	}
3598 
3599 	/* re-combine the user config with event to determine if permanent
3600 	 * addresses are to be removed from the interface list
3601 	 */
3602 	keep_addr = (!how && _keep_addr > 0);
3603 
3604 	INIT_LIST_HEAD(&del_list);
3605 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3606 		struct rt6_info *rt = NULL;
3607 
3608 		addrconf_del_dad_work(ifa);
3609 
3610 		write_unlock_bh(&idev->lock);
3611 		spin_lock_bh(&ifa->lock);
3612 
3613 		if (keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3614 		    !addr_is_local(&ifa->addr)) {
3615 			/* set state to skip the notifier below */
3616 			state = INET6_IFADDR_STATE_DEAD;
3617 			ifa->state = 0;
3618 			if (!(ifa->flags & IFA_F_NODAD))
3619 				ifa->flags |= IFA_F_TENTATIVE;
3620 
3621 			rt = ifa->rt;
3622 			ifa->rt = NULL;
3623 		} else {
3624 			state = ifa->state;
3625 			ifa->state = INET6_IFADDR_STATE_DEAD;
3626 
3627 			list_move(&ifa->if_list, &del_list);
3628 		}
3629 
3630 		spin_unlock_bh(&ifa->lock);
3631 
3632 		if (rt)
3633 			ip6_del_rt(rt);
3634 
3635 		if (state != INET6_IFADDR_STATE_DEAD) {
3636 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3637 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3638 		} else {
3639 			if (idev->cnf.forwarding)
3640 				addrconf_leave_anycast(ifa);
3641 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3642 		}
3643 
3644 		write_lock_bh(&idev->lock);
3645 	}
3646 
3647 	write_unlock_bh(&idev->lock);
3648 
3649 	/* now clean up addresses to be removed */
3650 	while (!list_empty(&del_list)) {
3651 		ifa = list_first_entry(&del_list,
3652 				       struct inet6_ifaddr, if_list);
3653 		list_del(&ifa->if_list);
3654 
3655 		in6_ifa_put(ifa);
3656 	}
3657 
3658 	/* Step 5: Discard anycast and multicast list */
3659 	if (how) {
3660 		ipv6_ac_destroy_dev(idev);
3661 		ipv6_mc_destroy_dev(idev);
3662 	} else {
3663 		ipv6_mc_down(idev);
3664 	}
3665 
3666 	idev->tstamp = jiffies;
3667 
3668 	/* Last: Shot the device (if unregistered) */
3669 	if (how) {
3670 		addrconf_sysctl_unregister(idev);
3671 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3672 		neigh_ifdown(&nd_tbl, dev);
3673 		in6_dev_put(idev);
3674 	}
3675 	return 0;
3676 }
3677 
3678 static void addrconf_rs_timer(unsigned long data)
3679 {
3680 	struct inet6_dev *idev = (struct inet6_dev *)data;
3681 	struct net_device *dev = idev->dev;
3682 	struct in6_addr lladdr;
3683 
3684 	write_lock(&idev->lock);
3685 	if (idev->dead || !(idev->if_flags & IF_READY))
3686 		goto out;
3687 
3688 	if (!ipv6_accept_ra(idev))
3689 		goto out;
3690 
3691 	/* Announcement received after solicitation was sent */
3692 	if (idev->if_flags & IF_RA_RCVD)
3693 		goto out;
3694 
3695 	if (idev->rs_probes++ < idev->cnf.rtr_solicits) {
3696 		write_unlock(&idev->lock);
3697 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3698 			ndisc_send_rs(dev, &lladdr,
3699 				      &in6addr_linklocal_allrouters);
3700 		else
3701 			goto put;
3702 
3703 		write_lock(&idev->lock);
3704 		/* The wait after the last probe can be shorter */
3705 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3706 					     idev->cnf.rtr_solicits) ?
3707 				      idev->cnf.rtr_solicit_delay :
3708 				      idev->cnf.rtr_solicit_interval);
3709 	} else {
3710 		/*
3711 		 * Note: we do not support deprecated "all on-link"
3712 		 * assumption any longer.
3713 		 */
3714 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3715 	}
3716 
3717 out:
3718 	write_unlock(&idev->lock);
3719 put:
3720 	in6_dev_put(idev);
3721 }
3722 
3723 /*
3724  *	Duplicate Address Detection
3725  */
3726 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3727 {
3728 	unsigned long rand_num;
3729 	struct inet6_dev *idev = ifp->idev;
3730 
3731 	if (ifp->flags & IFA_F_OPTIMISTIC)
3732 		rand_num = 0;
3733 	else
3734 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3735 
3736 	ifp->dad_probes = idev->cnf.dad_transmits;
3737 	addrconf_mod_dad_work(ifp, rand_num);
3738 }
3739 
3740 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3741 {
3742 	struct inet6_dev *idev = ifp->idev;
3743 	struct net_device *dev = idev->dev;
3744 	bool notify = false;
3745 
3746 	addrconf_join_solict(dev, &ifp->addr);
3747 
3748 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3749 
3750 	read_lock_bh(&idev->lock);
3751 	spin_lock(&ifp->lock);
3752 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3753 		goto out;
3754 
3755 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3756 	    idev->cnf.accept_dad < 1 ||
3757 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3758 	    ifp->flags & IFA_F_NODAD) {
3759 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3760 		spin_unlock(&ifp->lock);
3761 		read_unlock_bh(&idev->lock);
3762 
3763 		addrconf_dad_completed(ifp);
3764 		return;
3765 	}
3766 
3767 	if (!(idev->if_flags & IF_READY)) {
3768 		spin_unlock(&ifp->lock);
3769 		read_unlock_bh(&idev->lock);
3770 		/*
3771 		 * If the device is not ready:
3772 		 * - keep it tentative if it is a permanent address.
3773 		 * - otherwise, kill it.
3774 		 */
3775 		in6_ifa_hold(ifp);
3776 		addrconf_dad_stop(ifp, 0);
3777 		return;
3778 	}
3779 
3780 	/*
3781 	 * Optimistic nodes can start receiving
3782 	 * Frames right away
3783 	 */
3784 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3785 		ip6_ins_rt(ifp->rt);
3786 		if (ipv6_use_optimistic_addr(idev)) {
3787 			/* Because optimistic nodes can use this address,
3788 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3789 			 */
3790 			notify = true;
3791 		}
3792 	}
3793 
3794 	addrconf_dad_kick(ifp);
3795 out:
3796 	spin_unlock(&ifp->lock);
3797 	read_unlock_bh(&idev->lock);
3798 	if (notify)
3799 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3800 }
3801 
3802 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3803 {
3804 	bool begin_dad = false;
3805 
3806 	spin_lock_bh(&ifp->lock);
3807 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3808 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3809 		begin_dad = true;
3810 	}
3811 	spin_unlock_bh(&ifp->lock);
3812 
3813 	if (begin_dad)
3814 		addrconf_mod_dad_work(ifp, 0);
3815 }
3816 
3817 static void addrconf_dad_work(struct work_struct *w)
3818 {
3819 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3820 						struct inet6_ifaddr,
3821 						dad_work);
3822 	struct inet6_dev *idev = ifp->idev;
3823 	struct in6_addr mcaddr;
3824 
3825 	enum {
3826 		DAD_PROCESS,
3827 		DAD_BEGIN,
3828 		DAD_ABORT,
3829 	} action = DAD_PROCESS;
3830 
3831 	rtnl_lock();
3832 
3833 	spin_lock_bh(&ifp->lock);
3834 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3835 		action = DAD_BEGIN;
3836 		ifp->state = INET6_IFADDR_STATE_DAD;
3837 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3838 		action = DAD_ABORT;
3839 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
3840 	}
3841 	spin_unlock_bh(&ifp->lock);
3842 
3843 	if (action == DAD_BEGIN) {
3844 		addrconf_dad_begin(ifp);
3845 		goto out;
3846 	} else if (action == DAD_ABORT) {
3847 		addrconf_dad_stop(ifp, 1);
3848 		goto out;
3849 	}
3850 
3851 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
3852 		goto out;
3853 
3854 	write_lock_bh(&idev->lock);
3855 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3856 		write_unlock_bh(&idev->lock);
3857 		goto out;
3858 	}
3859 
3860 	spin_lock(&ifp->lock);
3861 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3862 		spin_unlock(&ifp->lock);
3863 		write_unlock_bh(&idev->lock);
3864 		goto out;
3865 	}
3866 
3867 	if (ifp->dad_probes == 0) {
3868 		/*
3869 		 * DAD was successful
3870 		 */
3871 
3872 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3873 		spin_unlock(&ifp->lock);
3874 		write_unlock_bh(&idev->lock);
3875 
3876 		addrconf_dad_completed(ifp);
3877 
3878 		goto out;
3879 	}
3880 
3881 	ifp->dad_probes--;
3882 	addrconf_mod_dad_work(ifp,
3883 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
3884 	spin_unlock(&ifp->lock);
3885 	write_unlock_bh(&idev->lock);
3886 
3887 	/* send a neighbour solicitation for our addr */
3888 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3889 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any);
3890 out:
3891 	in6_ifa_put(ifp);
3892 	rtnl_unlock();
3893 }
3894 
3895 /* ifp->idev must be at least read locked */
3896 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
3897 {
3898 	struct inet6_ifaddr *ifpiter;
3899 	struct inet6_dev *idev = ifp->idev;
3900 
3901 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
3902 		if (ifpiter->scope > IFA_LINK)
3903 			break;
3904 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
3905 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
3906 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
3907 		    IFA_F_PERMANENT)
3908 			return false;
3909 	}
3910 	return true;
3911 }
3912 
3913 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
3914 {
3915 	struct net_device *dev = ifp->idev->dev;
3916 	struct in6_addr lladdr;
3917 	bool send_rs, send_mld;
3918 
3919 	addrconf_del_dad_work(ifp);
3920 
3921 	/*
3922 	 *	Configure the address for reception. Now it is valid.
3923 	 */
3924 
3925 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
3926 
3927 	/* If added prefix is link local and we are prepared to process
3928 	   router advertisements, start sending router solicitations.
3929 	 */
3930 
3931 	read_lock_bh(&ifp->idev->lock);
3932 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
3933 	send_rs = send_mld &&
3934 		  ipv6_accept_ra(ifp->idev) &&
3935 		  ifp->idev->cnf.rtr_solicits > 0 &&
3936 		  (dev->flags&IFF_LOOPBACK) == 0;
3937 	read_unlock_bh(&ifp->idev->lock);
3938 
3939 	/* While dad is in progress mld report's source address is in6_addrany.
3940 	 * Resend with proper ll now.
3941 	 */
3942 	if (send_mld)
3943 		ipv6_mc_dad_complete(ifp->idev);
3944 
3945 	if (send_rs) {
3946 		/*
3947 		 *	If a host as already performed a random delay
3948 		 *	[...] as part of DAD [...] there is no need
3949 		 *	to delay again before sending the first RS
3950 		 */
3951 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3952 			return;
3953 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
3954 
3955 		write_lock_bh(&ifp->idev->lock);
3956 		spin_lock(&ifp->lock);
3957 		ifp->idev->rs_probes = 1;
3958 		ifp->idev->if_flags |= IF_RS_SENT;
3959 		addrconf_mod_rs_timer(ifp->idev,
3960 				      ifp->idev->cnf.rtr_solicit_interval);
3961 		spin_unlock(&ifp->lock);
3962 		write_unlock_bh(&ifp->idev->lock);
3963 	}
3964 }
3965 
3966 static void addrconf_dad_run(struct inet6_dev *idev)
3967 {
3968 	struct inet6_ifaddr *ifp;
3969 
3970 	read_lock_bh(&idev->lock);
3971 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3972 		spin_lock(&ifp->lock);
3973 		if (ifp->flags & IFA_F_TENTATIVE &&
3974 		    ifp->state == INET6_IFADDR_STATE_DAD)
3975 			addrconf_dad_kick(ifp);
3976 		spin_unlock(&ifp->lock);
3977 	}
3978 	read_unlock_bh(&idev->lock);
3979 }
3980 
3981 #ifdef CONFIG_PROC_FS
3982 struct if6_iter_state {
3983 	struct seq_net_private p;
3984 	int bucket;
3985 	int offset;
3986 };
3987 
3988 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
3989 {
3990 	struct inet6_ifaddr *ifa = NULL;
3991 	struct if6_iter_state *state = seq->private;
3992 	struct net *net = seq_file_net(seq);
3993 	int p = 0;
3994 
3995 	/* initial bucket if pos is 0 */
3996 	if (pos == 0) {
3997 		state->bucket = 0;
3998 		state->offset = 0;
3999 	}
4000 
4001 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4002 		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
4003 					 addr_lst) {
4004 			if (!net_eq(dev_net(ifa->idev->dev), net))
4005 				continue;
4006 			/* sync with offset */
4007 			if (p < state->offset) {
4008 				p++;
4009 				continue;
4010 			}
4011 			state->offset++;
4012 			return ifa;
4013 		}
4014 
4015 		/* prepare for next bucket */
4016 		state->offset = 0;
4017 		p = 0;
4018 	}
4019 	return NULL;
4020 }
4021 
4022 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4023 					 struct inet6_ifaddr *ifa)
4024 {
4025 	struct if6_iter_state *state = seq->private;
4026 	struct net *net = seq_file_net(seq);
4027 
4028 	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
4029 		if (!net_eq(dev_net(ifa->idev->dev), net))
4030 			continue;
4031 		state->offset++;
4032 		return ifa;
4033 	}
4034 
4035 	while (++state->bucket < IN6_ADDR_HSIZE) {
4036 		state->offset = 0;
4037 		hlist_for_each_entry_rcu_bh(ifa,
4038 				     &inet6_addr_lst[state->bucket], addr_lst) {
4039 			if (!net_eq(dev_net(ifa->idev->dev), net))
4040 				continue;
4041 			state->offset++;
4042 			return ifa;
4043 		}
4044 	}
4045 
4046 	return NULL;
4047 }
4048 
4049 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4050 	__acquires(rcu_bh)
4051 {
4052 	rcu_read_lock_bh();
4053 	return if6_get_first(seq, *pos);
4054 }
4055 
4056 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4057 {
4058 	struct inet6_ifaddr *ifa;
4059 
4060 	ifa = if6_get_next(seq, v);
4061 	++*pos;
4062 	return ifa;
4063 }
4064 
4065 static void if6_seq_stop(struct seq_file *seq, void *v)
4066 	__releases(rcu_bh)
4067 {
4068 	rcu_read_unlock_bh();
4069 }
4070 
4071 static int if6_seq_show(struct seq_file *seq, void *v)
4072 {
4073 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4074 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4075 		   &ifp->addr,
4076 		   ifp->idev->dev->ifindex,
4077 		   ifp->prefix_len,
4078 		   ifp->scope,
4079 		   (u8) ifp->flags,
4080 		   ifp->idev->dev->name);
4081 	return 0;
4082 }
4083 
4084 static const struct seq_operations if6_seq_ops = {
4085 	.start	= if6_seq_start,
4086 	.next	= if6_seq_next,
4087 	.show	= if6_seq_show,
4088 	.stop	= if6_seq_stop,
4089 };
4090 
4091 static int if6_seq_open(struct inode *inode, struct file *file)
4092 {
4093 	return seq_open_net(inode, file, &if6_seq_ops,
4094 			    sizeof(struct if6_iter_state));
4095 }
4096 
4097 static const struct file_operations if6_fops = {
4098 	.owner		= THIS_MODULE,
4099 	.open		= if6_seq_open,
4100 	.read		= seq_read,
4101 	.llseek		= seq_lseek,
4102 	.release	= seq_release_net,
4103 };
4104 
4105 static int __net_init if6_proc_net_init(struct net *net)
4106 {
4107 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
4108 		return -ENOMEM;
4109 	return 0;
4110 }
4111 
4112 static void __net_exit if6_proc_net_exit(struct net *net)
4113 {
4114 	remove_proc_entry("if_inet6", net->proc_net);
4115 }
4116 
4117 static struct pernet_operations if6_proc_net_ops = {
4118 	.init = if6_proc_net_init,
4119 	.exit = if6_proc_net_exit,
4120 };
4121 
4122 int __init if6_proc_init(void)
4123 {
4124 	return register_pernet_subsys(&if6_proc_net_ops);
4125 }
4126 
4127 void if6_proc_exit(void)
4128 {
4129 	unregister_pernet_subsys(&if6_proc_net_ops);
4130 }
4131 #endif	/* CONFIG_PROC_FS */
4132 
4133 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4134 /* Check if address is a home address configured on any interface. */
4135 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4136 {
4137 	int ret = 0;
4138 	struct inet6_ifaddr *ifp = NULL;
4139 	unsigned int hash = inet6_addr_hash(addr);
4140 
4141 	rcu_read_lock_bh();
4142 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
4143 		if (!net_eq(dev_net(ifp->idev->dev), net))
4144 			continue;
4145 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4146 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4147 			ret = 1;
4148 			break;
4149 		}
4150 	}
4151 	rcu_read_unlock_bh();
4152 	return ret;
4153 }
4154 #endif
4155 
4156 /*
4157  *	Periodic address status verification
4158  */
4159 
4160 static void addrconf_verify_rtnl(void)
4161 {
4162 	unsigned long now, next, next_sec, next_sched;
4163 	struct inet6_ifaddr *ifp;
4164 	int i;
4165 
4166 	ASSERT_RTNL();
4167 
4168 	rcu_read_lock_bh();
4169 	now = jiffies;
4170 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4171 
4172 	cancel_delayed_work(&addr_chk_work);
4173 
4174 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4175 restart:
4176 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4177 			unsigned long age;
4178 
4179 			/* When setting preferred_lft to a value not zero or
4180 			 * infinity, while valid_lft is infinity
4181 			 * IFA_F_PERMANENT has a non-infinity life time.
4182 			 */
4183 			if ((ifp->flags & IFA_F_PERMANENT) &&
4184 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4185 				continue;
4186 
4187 			spin_lock(&ifp->lock);
4188 			/* We try to batch several events at once. */
4189 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4190 
4191 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4192 			    age >= ifp->valid_lft) {
4193 				spin_unlock(&ifp->lock);
4194 				in6_ifa_hold(ifp);
4195 				ipv6_del_addr(ifp);
4196 				goto restart;
4197 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4198 				spin_unlock(&ifp->lock);
4199 				continue;
4200 			} else if (age >= ifp->prefered_lft) {
4201 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4202 				int deprecate = 0;
4203 
4204 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4205 					deprecate = 1;
4206 					ifp->flags |= IFA_F_DEPRECATED;
4207 				}
4208 
4209 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4210 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4211 					next = ifp->tstamp + ifp->valid_lft * HZ;
4212 
4213 				spin_unlock(&ifp->lock);
4214 
4215 				if (deprecate) {
4216 					in6_ifa_hold(ifp);
4217 
4218 					ipv6_ifa_notify(0, ifp);
4219 					in6_ifa_put(ifp);
4220 					goto restart;
4221 				}
4222 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4223 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4224 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4225 					ifp->idev->cnf.dad_transmits *
4226 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4227 
4228 				if (age >= ifp->prefered_lft - regen_advance) {
4229 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4230 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4231 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4232 					if (!ifp->regen_count && ifpub) {
4233 						ifp->regen_count++;
4234 						in6_ifa_hold(ifp);
4235 						in6_ifa_hold(ifpub);
4236 						spin_unlock(&ifp->lock);
4237 
4238 						spin_lock(&ifpub->lock);
4239 						ifpub->regen_count = 0;
4240 						spin_unlock(&ifpub->lock);
4241 						ipv6_create_tempaddr(ifpub, ifp);
4242 						in6_ifa_put(ifpub);
4243 						in6_ifa_put(ifp);
4244 						goto restart;
4245 					}
4246 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4247 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4248 				spin_unlock(&ifp->lock);
4249 			} else {
4250 				/* ifp->prefered_lft <= ifp->valid_lft */
4251 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4252 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4253 				spin_unlock(&ifp->lock);
4254 			}
4255 		}
4256 	}
4257 
4258 	next_sec = round_jiffies_up(next);
4259 	next_sched = next;
4260 
4261 	/* If rounded timeout is accurate enough, accept it. */
4262 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4263 		next_sched = next_sec;
4264 
4265 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4266 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4267 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4268 
4269 	ADBG(KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4270 	      now, next, next_sec, next_sched);
4271 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4272 	rcu_read_unlock_bh();
4273 }
4274 
4275 static void addrconf_verify_work(struct work_struct *w)
4276 {
4277 	rtnl_lock();
4278 	addrconf_verify_rtnl();
4279 	rtnl_unlock();
4280 }
4281 
4282 static void addrconf_verify(void)
4283 {
4284 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4285 }
4286 
4287 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4288 				     struct in6_addr **peer_pfx)
4289 {
4290 	struct in6_addr *pfx = NULL;
4291 
4292 	*peer_pfx = NULL;
4293 
4294 	if (addr)
4295 		pfx = nla_data(addr);
4296 
4297 	if (local) {
4298 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4299 			*peer_pfx = pfx;
4300 		pfx = nla_data(local);
4301 	}
4302 
4303 	return pfx;
4304 }
4305 
4306 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4307 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4308 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4309 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4310 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4311 };
4312 
4313 static int
4314 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
4315 {
4316 	struct net *net = sock_net(skb->sk);
4317 	struct ifaddrmsg *ifm;
4318 	struct nlattr *tb[IFA_MAX+1];
4319 	struct in6_addr *pfx, *peer_pfx;
4320 	u32 ifa_flags;
4321 	int err;
4322 
4323 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
4324 	if (err < 0)
4325 		return err;
4326 
4327 	ifm = nlmsg_data(nlh);
4328 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4329 	if (!pfx)
4330 		return -EINVAL;
4331 
4332 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4333 
4334 	/* We ignore other flags so far. */
4335 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4336 
4337 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4338 			      ifm->ifa_prefixlen);
4339 }
4340 
4341 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags,
4342 			     u32 prefered_lft, u32 valid_lft)
4343 {
4344 	u32 flags;
4345 	clock_t expires;
4346 	unsigned long timeout;
4347 	bool was_managetempaddr;
4348 	bool had_prefixroute;
4349 
4350 	ASSERT_RTNL();
4351 
4352 	if (!valid_lft || (prefered_lft > valid_lft))
4353 		return -EINVAL;
4354 
4355 	if (ifa_flags & IFA_F_MANAGETEMPADDR &&
4356 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4357 		return -EINVAL;
4358 
4359 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
4360 	if (addrconf_finite_timeout(timeout)) {
4361 		expires = jiffies_to_clock_t(timeout * HZ);
4362 		valid_lft = timeout;
4363 		flags = RTF_EXPIRES;
4364 	} else {
4365 		expires = 0;
4366 		flags = 0;
4367 		ifa_flags |= IFA_F_PERMANENT;
4368 	}
4369 
4370 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
4371 	if (addrconf_finite_timeout(timeout)) {
4372 		if (timeout == 0)
4373 			ifa_flags |= IFA_F_DEPRECATED;
4374 		prefered_lft = timeout;
4375 	}
4376 
4377 	spin_lock_bh(&ifp->lock);
4378 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4379 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4380 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4381 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4382 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4383 			IFA_F_NOPREFIXROUTE);
4384 	ifp->flags |= ifa_flags;
4385 	ifp->tstamp = jiffies;
4386 	ifp->valid_lft = valid_lft;
4387 	ifp->prefered_lft = prefered_lft;
4388 
4389 	spin_unlock_bh(&ifp->lock);
4390 	if (!(ifp->flags&IFA_F_TENTATIVE))
4391 		ipv6_ifa_notify(0, ifp);
4392 
4393 	if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
4394 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
4395 				      expires, flags);
4396 	} else if (had_prefixroute) {
4397 		enum cleanup_prefix_rt_t action;
4398 		unsigned long rt_expires;
4399 
4400 		write_lock_bh(&ifp->idev->lock);
4401 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4402 		write_unlock_bh(&ifp->idev->lock);
4403 
4404 		if (action != CLEANUP_PREFIX_RT_NOP) {
4405 			cleanup_prefix_route(ifp, rt_expires,
4406 				action == CLEANUP_PREFIX_RT_DEL);
4407 		}
4408 	}
4409 
4410 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4411 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
4412 			valid_lft = prefered_lft = 0;
4413 		manage_tempaddrs(ifp->idev, ifp, valid_lft, prefered_lft,
4414 				 !was_managetempaddr, jiffies);
4415 	}
4416 
4417 	addrconf_verify_rtnl();
4418 
4419 	return 0;
4420 }
4421 
4422 static int
4423 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
4424 {
4425 	struct net *net = sock_net(skb->sk);
4426 	struct ifaddrmsg *ifm;
4427 	struct nlattr *tb[IFA_MAX+1];
4428 	struct in6_addr *pfx, *peer_pfx;
4429 	struct inet6_ifaddr *ifa;
4430 	struct net_device *dev;
4431 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
4432 	u32 ifa_flags;
4433 	int err;
4434 
4435 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
4436 	if (err < 0)
4437 		return err;
4438 
4439 	ifm = nlmsg_data(nlh);
4440 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4441 	if (!pfx)
4442 		return -EINVAL;
4443 
4444 	if (tb[IFA_CACHEINFO]) {
4445 		struct ifa_cacheinfo *ci;
4446 
4447 		ci = nla_data(tb[IFA_CACHEINFO]);
4448 		valid_lft = ci->ifa_valid;
4449 		preferred_lft = ci->ifa_prefered;
4450 	} else {
4451 		preferred_lft = INFINITY_LIFE_TIME;
4452 		valid_lft = INFINITY_LIFE_TIME;
4453 	}
4454 
4455 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4456 	if (!dev)
4457 		return -ENODEV;
4458 
4459 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4460 
4461 	/* We ignore other flags so far. */
4462 	ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4463 		     IFA_F_NOPREFIXROUTE | IFA_F_MCAUTOJOIN;
4464 
4465 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
4466 	if (!ifa) {
4467 		/*
4468 		 * It would be best to check for !NLM_F_CREATE here but
4469 		 * userspace already relies on not having to provide this.
4470 		 */
4471 		return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,
4472 				      ifm->ifa_prefixlen, ifa_flags,
4473 				      preferred_lft, valid_lft);
4474 	}
4475 
4476 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4477 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4478 		err = -EEXIST;
4479 	else
4480 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
4481 
4482 	in6_ifa_put(ifa);
4483 
4484 	return err;
4485 }
4486 
4487 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4488 			  u8 scope, int ifindex)
4489 {
4490 	struct ifaddrmsg *ifm;
4491 
4492 	ifm = nlmsg_data(nlh);
4493 	ifm->ifa_family = AF_INET6;
4494 	ifm->ifa_prefixlen = prefixlen;
4495 	ifm->ifa_flags = flags;
4496 	ifm->ifa_scope = scope;
4497 	ifm->ifa_index = ifindex;
4498 }
4499 
4500 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4501 			 unsigned long tstamp, u32 preferred, u32 valid)
4502 {
4503 	struct ifa_cacheinfo ci;
4504 
4505 	ci.cstamp = cstamp_delta(cstamp);
4506 	ci.tstamp = cstamp_delta(tstamp);
4507 	ci.ifa_prefered = preferred;
4508 	ci.ifa_valid = valid;
4509 
4510 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4511 }
4512 
4513 static inline int rt_scope(int ifa_scope)
4514 {
4515 	if (ifa_scope & IFA_HOST)
4516 		return RT_SCOPE_HOST;
4517 	else if (ifa_scope & IFA_LINK)
4518 		return RT_SCOPE_LINK;
4519 	else if (ifa_scope & IFA_SITE)
4520 		return RT_SCOPE_SITE;
4521 	else
4522 		return RT_SCOPE_UNIVERSE;
4523 }
4524 
4525 static inline int inet6_ifaddr_msgsize(void)
4526 {
4527 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4528 	       + nla_total_size(16) /* IFA_LOCAL */
4529 	       + nla_total_size(16) /* IFA_ADDRESS */
4530 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4531 	       + nla_total_size(4)  /* IFA_FLAGS */;
4532 }
4533 
4534 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4535 			     u32 portid, u32 seq, int event, unsigned int flags)
4536 {
4537 	struct nlmsghdr  *nlh;
4538 	u32 preferred, valid;
4539 
4540 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4541 	if (!nlh)
4542 		return -EMSGSIZE;
4543 
4544 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4545 		      ifa->idev->dev->ifindex);
4546 
4547 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4548 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4549 		preferred = ifa->prefered_lft;
4550 		valid = ifa->valid_lft;
4551 		if (preferred != INFINITY_LIFE_TIME) {
4552 			long tval = (jiffies - ifa->tstamp)/HZ;
4553 			if (preferred > tval)
4554 				preferred -= tval;
4555 			else
4556 				preferred = 0;
4557 			if (valid != INFINITY_LIFE_TIME) {
4558 				if (valid > tval)
4559 					valid -= tval;
4560 				else
4561 					valid = 0;
4562 			}
4563 		}
4564 	} else {
4565 		preferred = INFINITY_LIFE_TIME;
4566 		valid = INFINITY_LIFE_TIME;
4567 	}
4568 
4569 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4570 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4571 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4572 			goto error;
4573 	} else
4574 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4575 			goto error;
4576 
4577 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4578 		goto error;
4579 
4580 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4581 		goto error;
4582 
4583 	nlmsg_end(skb, nlh);
4584 	return 0;
4585 
4586 error:
4587 	nlmsg_cancel(skb, nlh);
4588 	return -EMSGSIZE;
4589 }
4590 
4591 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4592 				u32 portid, u32 seq, int event, u16 flags)
4593 {
4594 	struct nlmsghdr  *nlh;
4595 	u8 scope = RT_SCOPE_UNIVERSE;
4596 	int ifindex = ifmca->idev->dev->ifindex;
4597 
4598 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4599 		scope = RT_SCOPE_SITE;
4600 
4601 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4602 	if (!nlh)
4603 		return -EMSGSIZE;
4604 
4605 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4606 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4607 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4608 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4609 		nlmsg_cancel(skb, nlh);
4610 		return -EMSGSIZE;
4611 	}
4612 
4613 	nlmsg_end(skb, nlh);
4614 	return 0;
4615 }
4616 
4617 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4618 				u32 portid, u32 seq, int event, unsigned int flags)
4619 {
4620 	struct nlmsghdr  *nlh;
4621 	u8 scope = RT_SCOPE_UNIVERSE;
4622 	int ifindex = ifaca->aca_idev->dev->ifindex;
4623 
4624 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4625 		scope = RT_SCOPE_SITE;
4626 
4627 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4628 	if (!nlh)
4629 		return -EMSGSIZE;
4630 
4631 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4632 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4633 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4634 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4635 		nlmsg_cancel(skb, nlh);
4636 		return -EMSGSIZE;
4637 	}
4638 
4639 	nlmsg_end(skb, nlh);
4640 	return 0;
4641 }
4642 
4643 enum addr_type_t {
4644 	UNICAST_ADDR,
4645 	MULTICAST_ADDR,
4646 	ANYCAST_ADDR,
4647 };
4648 
4649 /* called with rcu_read_lock() */
4650 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4651 			  struct netlink_callback *cb, enum addr_type_t type,
4652 			  int s_ip_idx, int *p_ip_idx)
4653 {
4654 	struct ifmcaddr6 *ifmca;
4655 	struct ifacaddr6 *ifaca;
4656 	int err = 1;
4657 	int ip_idx = *p_ip_idx;
4658 
4659 	read_lock_bh(&idev->lock);
4660 	switch (type) {
4661 	case UNICAST_ADDR: {
4662 		struct inet6_ifaddr *ifa;
4663 
4664 		/* unicast address incl. temp addr */
4665 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4666 			if (++ip_idx < s_ip_idx)
4667 				continue;
4668 			err = inet6_fill_ifaddr(skb, ifa,
4669 						NETLINK_CB(cb->skb).portid,
4670 						cb->nlh->nlmsg_seq,
4671 						RTM_NEWADDR,
4672 						NLM_F_MULTI);
4673 			if (err < 0)
4674 				break;
4675 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4676 		}
4677 		break;
4678 	}
4679 	case MULTICAST_ADDR:
4680 		/* multicast address */
4681 		for (ifmca = idev->mc_list; ifmca;
4682 		     ifmca = ifmca->next, ip_idx++) {
4683 			if (ip_idx < s_ip_idx)
4684 				continue;
4685 			err = inet6_fill_ifmcaddr(skb, ifmca,
4686 						  NETLINK_CB(cb->skb).portid,
4687 						  cb->nlh->nlmsg_seq,
4688 						  RTM_GETMULTICAST,
4689 						  NLM_F_MULTI);
4690 			if (err < 0)
4691 				break;
4692 		}
4693 		break;
4694 	case ANYCAST_ADDR:
4695 		/* anycast address */
4696 		for (ifaca = idev->ac_list; ifaca;
4697 		     ifaca = ifaca->aca_next, ip_idx++) {
4698 			if (ip_idx < s_ip_idx)
4699 				continue;
4700 			err = inet6_fill_ifacaddr(skb, ifaca,
4701 						  NETLINK_CB(cb->skb).portid,
4702 						  cb->nlh->nlmsg_seq,
4703 						  RTM_GETANYCAST,
4704 						  NLM_F_MULTI);
4705 			if (err < 0)
4706 				break;
4707 		}
4708 		break;
4709 	default:
4710 		break;
4711 	}
4712 	read_unlock_bh(&idev->lock);
4713 	*p_ip_idx = ip_idx;
4714 	return err;
4715 }
4716 
4717 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
4718 			   enum addr_type_t type)
4719 {
4720 	struct net *net = sock_net(skb->sk);
4721 	int h, s_h;
4722 	int idx, ip_idx;
4723 	int s_idx, s_ip_idx;
4724 	struct net_device *dev;
4725 	struct inet6_dev *idev;
4726 	struct hlist_head *head;
4727 
4728 	s_h = cb->args[0];
4729 	s_idx = idx = cb->args[1];
4730 	s_ip_idx = ip_idx = cb->args[2];
4731 
4732 	rcu_read_lock();
4733 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
4734 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4735 		idx = 0;
4736 		head = &net->dev_index_head[h];
4737 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4738 			if (idx < s_idx)
4739 				goto cont;
4740 			if (h > s_h || idx > s_idx)
4741 				s_ip_idx = 0;
4742 			ip_idx = 0;
4743 			idev = __in6_dev_get(dev);
4744 			if (!idev)
4745 				goto cont;
4746 
4747 			if (in6_dump_addrs(idev, skb, cb, type,
4748 					   s_ip_idx, &ip_idx) < 0)
4749 				goto done;
4750 cont:
4751 			idx++;
4752 		}
4753 	}
4754 done:
4755 	rcu_read_unlock();
4756 	cb->args[0] = h;
4757 	cb->args[1] = idx;
4758 	cb->args[2] = ip_idx;
4759 
4760 	return skb->len;
4761 }
4762 
4763 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
4764 {
4765 	enum addr_type_t type = UNICAST_ADDR;
4766 
4767 	return inet6_dump_addr(skb, cb, type);
4768 }
4769 
4770 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
4771 {
4772 	enum addr_type_t type = MULTICAST_ADDR;
4773 
4774 	return inet6_dump_addr(skb, cb, type);
4775 }
4776 
4777 
4778 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
4779 {
4780 	enum addr_type_t type = ANYCAST_ADDR;
4781 
4782 	return inet6_dump_addr(skb, cb, type);
4783 }
4784 
4785 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh)
4786 {
4787 	struct net *net = sock_net(in_skb->sk);
4788 	struct ifaddrmsg *ifm;
4789 	struct nlattr *tb[IFA_MAX+1];
4790 	struct in6_addr *addr = NULL, *peer;
4791 	struct net_device *dev = NULL;
4792 	struct inet6_ifaddr *ifa;
4793 	struct sk_buff *skb;
4794 	int err;
4795 
4796 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
4797 	if (err < 0)
4798 		goto errout;
4799 
4800 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
4801 	if (!addr) {
4802 		err = -EINVAL;
4803 		goto errout;
4804 	}
4805 
4806 	ifm = nlmsg_data(nlh);
4807 	if (ifm->ifa_index)
4808 		dev = __dev_get_by_index(net, ifm->ifa_index);
4809 
4810 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
4811 	if (!ifa) {
4812 		err = -EADDRNOTAVAIL;
4813 		goto errout;
4814 	}
4815 
4816 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
4817 	if (!skb) {
4818 		err = -ENOBUFS;
4819 		goto errout_ifa;
4820 	}
4821 
4822 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
4823 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
4824 	if (err < 0) {
4825 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4826 		WARN_ON(err == -EMSGSIZE);
4827 		kfree_skb(skb);
4828 		goto errout_ifa;
4829 	}
4830 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
4831 errout_ifa:
4832 	in6_ifa_put(ifa);
4833 errout:
4834 	return err;
4835 }
4836 
4837 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
4838 {
4839 	struct sk_buff *skb;
4840 	struct net *net = dev_net(ifa->idev->dev);
4841 	int err = -ENOBUFS;
4842 
4843 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
4844 	if (!skb)
4845 		goto errout;
4846 
4847 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
4848 	if (err < 0) {
4849 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4850 		WARN_ON(err == -EMSGSIZE);
4851 		kfree_skb(skb);
4852 		goto errout;
4853 	}
4854 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
4855 	return;
4856 errout:
4857 	if (err < 0)
4858 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
4859 }
4860 
4861 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
4862 				__s32 *array, int bytes)
4863 {
4864 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4865 
4866 	memset(array, 0, bytes);
4867 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4868 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4869 	array[DEVCONF_MTU6] = cnf->mtu6;
4870 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4871 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4872 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4873 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4874 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4875 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
4876 		jiffies_to_msecs(cnf->rtr_solicit_interval);
4877 	array[DEVCONF_RTR_SOLICIT_DELAY] =
4878 		jiffies_to_msecs(cnf->rtr_solicit_delay);
4879 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
4880 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
4881 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
4882 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
4883 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
4884 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
4885 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
4886 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
4887 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
4888 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
4889 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
4890 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
4891 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
4892 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
4893 #ifdef CONFIG_IPV6_ROUTER_PREF
4894 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
4895 	array[DEVCONF_RTR_PROBE_INTERVAL] =
4896 		jiffies_to_msecs(cnf->rtr_probe_interval);
4897 #ifdef CONFIG_IPV6_ROUTE_INFO
4898 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
4899 #endif
4900 #endif
4901 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
4902 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
4903 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4904 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
4905 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
4906 #endif
4907 #ifdef CONFIG_IPV6_MROUTE
4908 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
4909 #endif
4910 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
4911 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
4912 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
4913 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
4914 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
4915 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
4916 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
4917 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
4918 	/* we omit DEVCONF_STABLE_SECRET for now */
4919 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
4920 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
4921 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
4922 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
4923 }
4924 
4925 static inline size_t inet6_ifla6_size(void)
4926 {
4927 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
4928 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
4929 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
4930 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
4931 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
4932 	     + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */
4933 }
4934 
4935 static inline size_t inet6_if_nlmsg_size(void)
4936 {
4937 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
4938 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
4939 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
4940 	       + nla_total_size(4) /* IFLA_MTU */
4941 	       + nla_total_size(4) /* IFLA_LINK */
4942 	       + nla_total_size(1) /* IFLA_OPERSTATE */
4943 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
4944 }
4945 
4946 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
4947 				      int items, int bytes)
4948 {
4949 	int i;
4950 	int pad = bytes - sizeof(u64) * items;
4951 	BUG_ON(pad < 0);
4952 
4953 	/* Use put_unaligned() because stats may not be aligned for u64. */
4954 	put_unaligned(items, &stats[0]);
4955 	for (i = 1; i < items; i++)
4956 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
4957 
4958 	memset(&stats[items], 0, pad);
4959 }
4960 
4961 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
4962 					int bytes, size_t syncpoff)
4963 {
4964 	int i, c;
4965 	u64 buff[IPSTATS_MIB_MAX];
4966 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
4967 
4968 	BUG_ON(pad < 0);
4969 
4970 	memset(buff, 0, sizeof(buff));
4971 	buff[0] = IPSTATS_MIB_MAX;
4972 
4973 	for_each_possible_cpu(c) {
4974 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
4975 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
4976 	}
4977 
4978 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
4979 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
4980 }
4981 
4982 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
4983 			     int bytes)
4984 {
4985 	switch (attrtype) {
4986 	case IFLA_INET6_STATS:
4987 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
4988 				     offsetof(struct ipstats_mib, syncp));
4989 		break;
4990 	case IFLA_INET6_ICMP6STATS:
4991 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, ICMP6_MIB_MAX, bytes);
4992 		break;
4993 	}
4994 }
4995 
4996 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
4997 				  u32 ext_filter_mask)
4998 {
4999 	struct nlattr *nla;
5000 	struct ifla_cacheinfo ci;
5001 
5002 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5003 		goto nla_put_failure;
5004 	ci.max_reasm_len = IPV6_MAXPLEN;
5005 	ci.tstamp = cstamp_delta(idev->tstamp);
5006 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5007 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5008 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5009 		goto nla_put_failure;
5010 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5011 	if (!nla)
5012 		goto nla_put_failure;
5013 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5014 
5015 	/* XXX - MC not implemented */
5016 
5017 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5018 		return 0;
5019 
5020 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5021 	if (!nla)
5022 		goto nla_put_failure;
5023 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5024 
5025 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5026 	if (!nla)
5027 		goto nla_put_failure;
5028 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5029 
5030 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5031 	if (!nla)
5032 		goto nla_put_failure;
5033 
5034 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->addr_gen_mode))
5035 		goto nla_put_failure;
5036 
5037 	read_lock_bh(&idev->lock);
5038 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5039 	read_unlock_bh(&idev->lock);
5040 
5041 	return 0;
5042 
5043 nla_put_failure:
5044 	return -EMSGSIZE;
5045 }
5046 
5047 static size_t inet6_get_link_af_size(const struct net_device *dev,
5048 				     u32 ext_filter_mask)
5049 {
5050 	if (!__in6_dev_get(dev))
5051 		return 0;
5052 
5053 	return inet6_ifla6_size();
5054 }
5055 
5056 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5057 			      u32 ext_filter_mask)
5058 {
5059 	struct inet6_dev *idev = __in6_dev_get(dev);
5060 
5061 	if (!idev)
5062 		return -ENODATA;
5063 
5064 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5065 		return -EMSGSIZE;
5066 
5067 	return 0;
5068 }
5069 
5070 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5071 {
5072 	struct inet6_ifaddr *ifp;
5073 	struct net_device *dev = idev->dev;
5074 	bool clear_token, update_rs = false;
5075 	struct in6_addr ll_addr;
5076 
5077 	ASSERT_RTNL();
5078 
5079 	if (!token)
5080 		return -EINVAL;
5081 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5082 		return -EINVAL;
5083 	if (!ipv6_accept_ra(idev))
5084 		return -EINVAL;
5085 	if (idev->cnf.rtr_solicits <= 0)
5086 		return -EINVAL;
5087 
5088 	write_lock_bh(&idev->lock);
5089 
5090 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5091 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5092 
5093 	write_unlock_bh(&idev->lock);
5094 
5095 	clear_token = ipv6_addr_any(token);
5096 	if (clear_token)
5097 		goto update_lft;
5098 
5099 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5100 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5101 			     IFA_F_OPTIMISTIC)) {
5102 		/* If we're not ready, then normal ifup will take care
5103 		 * of this. Otherwise, we need to request our rs here.
5104 		 */
5105 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5106 		update_rs = true;
5107 	}
5108 
5109 update_lft:
5110 	write_lock_bh(&idev->lock);
5111 
5112 	if (update_rs) {
5113 		idev->if_flags |= IF_RS_SENT;
5114 		idev->rs_probes = 1;
5115 		addrconf_mod_rs_timer(idev, idev->cnf.rtr_solicit_interval);
5116 	}
5117 
5118 	/* Well, that's kinda nasty ... */
5119 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5120 		spin_lock(&ifp->lock);
5121 		if (ifp->tokenized) {
5122 			ifp->valid_lft = 0;
5123 			ifp->prefered_lft = 0;
5124 		}
5125 		spin_unlock(&ifp->lock);
5126 	}
5127 
5128 	write_unlock_bh(&idev->lock);
5129 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5130 	addrconf_verify_rtnl();
5131 	return 0;
5132 }
5133 
5134 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5135 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5136 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5137 };
5138 
5139 static int inet6_validate_link_af(const struct net_device *dev,
5140 				  const struct nlattr *nla)
5141 {
5142 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5143 
5144 	if (dev && !__in6_dev_get(dev))
5145 		return -EAFNOSUPPORT;
5146 
5147 	return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy);
5148 }
5149 
5150 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5151 {
5152 	int err = -EINVAL;
5153 	struct inet6_dev *idev = __in6_dev_get(dev);
5154 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5155 
5156 	if (!idev)
5157 		return -EAFNOSUPPORT;
5158 
5159 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL) < 0)
5160 		BUG();
5161 
5162 	if (tb[IFLA_INET6_TOKEN]) {
5163 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5164 		if (err)
5165 			return err;
5166 	}
5167 
5168 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5169 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5170 
5171 		if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5172 		    mode != IN6_ADDR_GEN_MODE_NONE &&
5173 		    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5174 		    mode != IN6_ADDR_GEN_MODE_RANDOM)
5175 			return -EINVAL;
5176 
5177 		if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5178 		    !idev->cnf.stable_secret.initialized &&
5179 		    !dev_net(dev)->ipv6.devconf_dflt->stable_secret.initialized)
5180 			return -EINVAL;
5181 
5182 		idev->addr_gen_mode = mode;
5183 		err = 0;
5184 	}
5185 
5186 	return err;
5187 }
5188 
5189 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5190 			     u32 portid, u32 seq, int event, unsigned int flags)
5191 {
5192 	struct net_device *dev = idev->dev;
5193 	struct ifinfomsg *hdr;
5194 	struct nlmsghdr *nlh;
5195 	void *protoinfo;
5196 
5197 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5198 	if (!nlh)
5199 		return -EMSGSIZE;
5200 
5201 	hdr = nlmsg_data(nlh);
5202 	hdr->ifi_family = AF_INET6;
5203 	hdr->__ifi_pad = 0;
5204 	hdr->ifi_type = dev->type;
5205 	hdr->ifi_index = dev->ifindex;
5206 	hdr->ifi_flags = dev_get_flags(dev);
5207 	hdr->ifi_change = 0;
5208 
5209 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5210 	    (dev->addr_len &&
5211 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5212 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5213 	    (dev->ifindex != dev_get_iflink(dev) &&
5214 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5215 	    nla_put_u8(skb, IFLA_OPERSTATE,
5216 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5217 		goto nla_put_failure;
5218 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
5219 	if (!protoinfo)
5220 		goto nla_put_failure;
5221 
5222 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5223 		goto nla_put_failure;
5224 
5225 	nla_nest_end(skb, protoinfo);
5226 	nlmsg_end(skb, nlh);
5227 	return 0;
5228 
5229 nla_put_failure:
5230 	nlmsg_cancel(skb, nlh);
5231 	return -EMSGSIZE;
5232 }
5233 
5234 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5235 {
5236 	struct net *net = sock_net(skb->sk);
5237 	int h, s_h;
5238 	int idx = 0, s_idx;
5239 	struct net_device *dev;
5240 	struct inet6_dev *idev;
5241 	struct hlist_head *head;
5242 
5243 	s_h = cb->args[0];
5244 	s_idx = cb->args[1];
5245 
5246 	rcu_read_lock();
5247 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5248 		idx = 0;
5249 		head = &net->dev_index_head[h];
5250 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5251 			if (idx < s_idx)
5252 				goto cont;
5253 			idev = __in6_dev_get(dev);
5254 			if (!idev)
5255 				goto cont;
5256 			if (inet6_fill_ifinfo(skb, idev,
5257 					      NETLINK_CB(cb->skb).portid,
5258 					      cb->nlh->nlmsg_seq,
5259 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5260 				goto out;
5261 cont:
5262 			idx++;
5263 		}
5264 	}
5265 out:
5266 	rcu_read_unlock();
5267 	cb->args[1] = idx;
5268 	cb->args[0] = h;
5269 
5270 	return skb->len;
5271 }
5272 
5273 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5274 {
5275 	struct sk_buff *skb;
5276 	struct net *net = dev_net(idev->dev);
5277 	int err = -ENOBUFS;
5278 
5279 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5280 	if (!skb)
5281 		goto errout;
5282 
5283 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5284 	if (err < 0) {
5285 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5286 		WARN_ON(err == -EMSGSIZE);
5287 		kfree_skb(skb);
5288 		goto errout;
5289 	}
5290 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5291 	return;
5292 errout:
5293 	if (err < 0)
5294 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5295 }
5296 
5297 static inline size_t inet6_prefix_nlmsg_size(void)
5298 {
5299 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5300 	       + nla_total_size(sizeof(struct in6_addr))
5301 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5302 }
5303 
5304 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5305 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5306 			     int event, unsigned int flags)
5307 {
5308 	struct prefixmsg *pmsg;
5309 	struct nlmsghdr *nlh;
5310 	struct prefix_cacheinfo	ci;
5311 
5312 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5313 	if (!nlh)
5314 		return -EMSGSIZE;
5315 
5316 	pmsg = nlmsg_data(nlh);
5317 	pmsg->prefix_family = AF_INET6;
5318 	pmsg->prefix_pad1 = 0;
5319 	pmsg->prefix_pad2 = 0;
5320 	pmsg->prefix_ifindex = idev->dev->ifindex;
5321 	pmsg->prefix_len = pinfo->prefix_len;
5322 	pmsg->prefix_type = pinfo->type;
5323 	pmsg->prefix_pad3 = 0;
5324 	pmsg->prefix_flags = 0;
5325 	if (pinfo->onlink)
5326 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5327 	if (pinfo->autoconf)
5328 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5329 
5330 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5331 		goto nla_put_failure;
5332 	ci.preferred_time = ntohl(pinfo->prefered);
5333 	ci.valid_time = ntohl(pinfo->valid);
5334 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5335 		goto nla_put_failure;
5336 	nlmsg_end(skb, nlh);
5337 	return 0;
5338 
5339 nla_put_failure:
5340 	nlmsg_cancel(skb, nlh);
5341 	return -EMSGSIZE;
5342 }
5343 
5344 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5345 			 struct prefix_info *pinfo)
5346 {
5347 	struct sk_buff *skb;
5348 	struct net *net = dev_net(idev->dev);
5349 	int err = -ENOBUFS;
5350 
5351 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5352 	if (!skb)
5353 		goto errout;
5354 
5355 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5356 	if (err < 0) {
5357 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5358 		WARN_ON(err == -EMSGSIZE);
5359 		kfree_skb(skb);
5360 		goto errout;
5361 	}
5362 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5363 	return;
5364 errout:
5365 	if (err < 0)
5366 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5367 }
5368 
5369 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5370 {
5371 	struct net *net = dev_net(ifp->idev->dev);
5372 
5373 	if (event)
5374 		ASSERT_RTNL();
5375 
5376 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5377 
5378 	switch (event) {
5379 	case RTM_NEWADDR:
5380 		/*
5381 		 * If the address was optimistic
5382 		 * we inserted the route at the start of
5383 		 * our DAD process, so we don't need
5384 		 * to do it again
5385 		 */
5386 		if (!(ifp->rt->rt6i_node))
5387 			ip6_ins_rt(ifp->rt);
5388 		if (ifp->idev->cnf.forwarding)
5389 			addrconf_join_anycast(ifp);
5390 		if (!ipv6_addr_any(&ifp->peer_addr))
5391 			addrconf_prefix_route(&ifp->peer_addr, 128,
5392 					      ifp->idev->dev, 0, 0);
5393 		break;
5394 	case RTM_DELADDR:
5395 		if (ifp->idev->cnf.forwarding)
5396 			addrconf_leave_anycast(ifp);
5397 		addrconf_leave_solict(ifp->idev, &ifp->addr);
5398 		if (!ipv6_addr_any(&ifp->peer_addr)) {
5399 			struct rt6_info *rt;
5400 
5401 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5402 						       ifp->idev->dev, 0, 0);
5403 			if (rt)
5404 				ip6_del_rt(rt);
5405 		}
5406 		if (ifp->rt) {
5407 			dst_hold(&ifp->rt->dst);
5408 			ip6_del_rt(ifp->rt);
5409 		}
5410 		rt_genid_bump_ipv6(net);
5411 		break;
5412 	}
5413 	atomic_inc(&net->ipv6.dev_addr_genid);
5414 }
5415 
5416 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5417 {
5418 	rcu_read_lock_bh();
5419 	if (likely(ifp->idev->dead == 0))
5420 		__ipv6_ifa_notify(event, ifp);
5421 	rcu_read_unlock_bh();
5422 }
5423 
5424 #ifdef CONFIG_SYSCTL
5425 
5426 static
5427 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
5428 			   void __user *buffer, size_t *lenp, loff_t *ppos)
5429 {
5430 	int *valp = ctl->data;
5431 	int val = *valp;
5432 	loff_t pos = *ppos;
5433 	struct ctl_table lctl;
5434 	int ret;
5435 
5436 	/*
5437 	 * ctl->data points to idev->cnf.forwarding, we should
5438 	 * not modify it until we get the rtnl lock.
5439 	 */
5440 	lctl = *ctl;
5441 	lctl.data = &val;
5442 
5443 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5444 
5445 	if (write)
5446 		ret = addrconf_fixup_forwarding(ctl, valp, val);
5447 	if (ret)
5448 		*ppos = pos;
5449 	return ret;
5450 }
5451 
5452 static
5453 int addrconf_sysctl_hop_limit(struct ctl_table *ctl, int write,
5454                               void __user *buffer, size_t *lenp, loff_t *ppos)
5455 {
5456 	struct ctl_table lctl;
5457 	int min_hl = 1, max_hl = 255;
5458 
5459 	lctl = *ctl;
5460 	lctl.extra1 = &min_hl;
5461 	lctl.extra2 = &max_hl;
5462 
5463 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
5464 }
5465 
5466 static
5467 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
5468 			void __user *buffer, size_t *lenp, loff_t *ppos)
5469 {
5470 	struct inet6_dev *idev = ctl->extra1;
5471 	int min_mtu = IPV6_MIN_MTU;
5472 	struct ctl_table lctl;
5473 
5474 	lctl = *ctl;
5475 	lctl.extra1 = &min_mtu;
5476 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
5477 
5478 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
5479 }
5480 
5481 static void dev_disable_change(struct inet6_dev *idev)
5482 {
5483 	struct netdev_notifier_info info;
5484 
5485 	if (!idev || !idev->dev)
5486 		return;
5487 
5488 	netdev_notifier_info_init(&info, idev->dev);
5489 	if (idev->cnf.disable_ipv6)
5490 		addrconf_notify(NULL, NETDEV_DOWN, &info);
5491 	else
5492 		addrconf_notify(NULL, NETDEV_UP, &info);
5493 }
5494 
5495 static void addrconf_disable_change(struct net *net, __s32 newf)
5496 {
5497 	struct net_device *dev;
5498 	struct inet6_dev *idev;
5499 
5500 	rcu_read_lock();
5501 	for_each_netdev_rcu(net, dev) {
5502 		idev = __in6_dev_get(dev);
5503 		if (idev) {
5504 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
5505 			idev->cnf.disable_ipv6 = newf;
5506 			if (changed)
5507 				dev_disable_change(idev);
5508 		}
5509 	}
5510 	rcu_read_unlock();
5511 }
5512 
5513 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
5514 {
5515 	struct net *net;
5516 	int old;
5517 
5518 	if (!rtnl_trylock())
5519 		return restart_syscall();
5520 
5521 	net = (struct net *)table->extra2;
5522 	old = *p;
5523 	*p = newf;
5524 
5525 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
5526 		rtnl_unlock();
5527 		return 0;
5528 	}
5529 
5530 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
5531 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
5532 		addrconf_disable_change(net, newf);
5533 	} else if ((!newf) ^ (!old))
5534 		dev_disable_change((struct inet6_dev *)table->extra1);
5535 
5536 	rtnl_unlock();
5537 	return 0;
5538 }
5539 
5540 static
5541 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
5542 			    void __user *buffer, size_t *lenp, loff_t *ppos)
5543 {
5544 	int *valp = ctl->data;
5545 	int val = *valp;
5546 	loff_t pos = *ppos;
5547 	struct ctl_table lctl;
5548 	int ret;
5549 
5550 	/*
5551 	 * ctl->data points to idev->cnf.disable_ipv6, we should
5552 	 * not modify it until we get the rtnl lock.
5553 	 */
5554 	lctl = *ctl;
5555 	lctl.data = &val;
5556 
5557 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5558 
5559 	if (write)
5560 		ret = addrconf_disable_ipv6(ctl, valp, val);
5561 	if (ret)
5562 		*ppos = pos;
5563 	return ret;
5564 }
5565 
5566 static
5567 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
5568 			      void __user *buffer, size_t *lenp, loff_t *ppos)
5569 {
5570 	int *valp = ctl->data;
5571 	int ret;
5572 	int old, new;
5573 
5574 	old = *valp;
5575 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5576 	new = *valp;
5577 
5578 	if (write && old != new) {
5579 		struct net *net = ctl->extra2;
5580 
5581 		if (!rtnl_trylock())
5582 			return restart_syscall();
5583 
5584 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
5585 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
5586 						     NETCONFA_IFINDEX_DEFAULT,
5587 						     net->ipv6.devconf_dflt);
5588 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
5589 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
5590 						     NETCONFA_IFINDEX_ALL,
5591 						     net->ipv6.devconf_all);
5592 		else {
5593 			struct inet6_dev *idev = ctl->extra1;
5594 
5595 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
5596 						     idev->dev->ifindex,
5597 						     &idev->cnf);
5598 		}
5599 		rtnl_unlock();
5600 	}
5601 
5602 	return ret;
5603 }
5604 
5605 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
5606 					 void __user *buffer, size_t *lenp,
5607 					 loff_t *ppos)
5608 {
5609 	int err;
5610 	struct in6_addr addr;
5611 	char str[IPV6_MAX_STRLEN];
5612 	struct ctl_table lctl = *ctl;
5613 	struct net *net = ctl->extra2;
5614 	struct ipv6_stable_secret *secret = ctl->data;
5615 
5616 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
5617 		return -EIO;
5618 
5619 	lctl.maxlen = IPV6_MAX_STRLEN;
5620 	lctl.data = str;
5621 
5622 	if (!rtnl_trylock())
5623 		return restart_syscall();
5624 
5625 	if (!write && !secret->initialized) {
5626 		err = -EIO;
5627 		goto out;
5628 	}
5629 
5630 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
5631 	if (err >= sizeof(str)) {
5632 		err = -EIO;
5633 		goto out;
5634 	}
5635 
5636 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
5637 	if (err || !write)
5638 		goto out;
5639 
5640 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
5641 		err = -EIO;
5642 		goto out;
5643 	}
5644 
5645 	secret->initialized = true;
5646 	secret->secret = addr;
5647 
5648 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
5649 		struct net_device *dev;
5650 
5651 		for_each_netdev(net, dev) {
5652 			struct inet6_dev *idev = __in6_dev_get(dev);
5653 
5654 			if (idev) {
5655 				idev->addr_gen_mode =
5656 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5657 			}
5658 		}
5659 	} else {
5660 		struct inet6_dev *idev = ctl->extra1;
5661 
5662 		idev->addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5663 	}
5664 
5665 out:
5666 	rtnl_unlock();
5667 
5668 	return err;
5669 }
5670 
5671 static
5672 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
5673 						int write,
5674 						void __user *buffer,
5675 						size_t *lenp,
5676 						loff_t *ppos)
5677 {
5678 	int *valp = ctl->data;
5679 	int val = *valp;
5680 	loff_t pos = *ppos;
5681 	struct ctl_table lctl;
5682 	int ret;
5683 
5684 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
5685 	 * we should not modify it until we get the rtnl lock.
5686 	 */
5687 	lctl = *ctl;
5688 	lctl.data = &val;
5689 
5690 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5691 
5692 	if (write)
5693 		ret = addrconf_fixup_linkdown(ctl, valp, val);
5694 	if (ret)
5695 		*ppos = pos;
5696 	return ret;
5697 }
5698 
5699 static const struct ctl_table addrconf_sysctl[] = {
5700 	{
5701 		.procname	= "forwarding",
5702 		.data		= &ipv6_devconf.forwarding,
5703 		.maxlen		= sizeof(int),
5704 		.mode		= 0644,
5705 		.proc_handler	= addrconf_sysctl_forward,
5706 	},
5707 	{
5708 		.procname	= "hop_limit",
5709 		.data		= &ipv6_devconf.hop_limit,
5710 		.maxlen		= sizeof(int),
5711 		.mode		= 0644,
5712 		.proc_handler	= addrconf_sysctl_hop_limit,
5713 	},
5714 	{
5715 		.procname	= "mtu",
5716 		.data		= &ipv6_devconf.mtu6,
5717 		.maxlen		= sizeof(int),
5718 		.mode		= 0644,
5719 		.proc_handler	= addrconf_sysctl_mtu,
5720 	},
5721 	{
5722 		.procname	= "accept_ra",
5723 		.data		= &ipv6_devconf.accept_ra,
5724 		.maxlen		= sizeof(int),
5725 		.mode		= 0644,
5726 		.proc_handler	= proc_dointvec,
5727 	},
5728 	{
5729 		.procname	= "accept_redirects",
5730 		.data		= &ipv6_devconf.accept_redirects,
5731 		.maxlen		= sizeof(int),
5732 		.mode		= 0644,
5733 		.proc_handler	= proc_dointvec,
5734 	},
5735 	{
5736 		.procname	= "autoconf",
5737 		.data		= &ipv6_devconf.autoconf,
5738 		.maxlen		= sizeof(int),
5739 		.mode		= 0644,
5740 		.proc_handler	= proc_dointvec,
5741 	},
5742 	{
5743 		.procname	= "dad_transmits",
5744 		.data		= &ipv6_devconf.dad_transmits,
5745 		.maxlen		= sizeof(int),
5746 		.mode		= 0644,
5747 		.proc_handler	= proc_dointvec,
5748 	},
5749 	{
5750 		.procname	= "router_solicitations",
5751 		.data		= &ipv6_devconf.rtr_solicits,
5752 		.maxlen		= sizeof(int),
5753 		.mode		= 0644,
5754 		.proc_handler	= proc_dointvec,
5755 	},
5756 	{
5757 		.procname	= "router_solicitation_interval",
5758 		.data		= &ipv6_devconf.rtr_solicit_interval,
5759 		.maxlen		= sizeof(int),
5760 		.mode		= 0644,
5761 		.proc_handler	= proc_dointvec_jiffies,
5762 	},
5763 	{
5764 		.procname	= "router_solicitation_delay",
5765 		.data		= &ipv6_devconf.rtr_solicit_delay,
5766 		.maxlen		= sizeof(int),
5767 		.mode		= 0644,
5768 		.proc_handler	= proc_dointvec_jiffies,
5769 	},
5770 	{
5771 		.procname	= "force_mld_version",
5772 		.data		= &ipv6_devconf.force_mld_version,
5773 		.maxlen		= sizeof(int),
5774 		.mode		= 0644,
5775 		.proc_handler	= proc_dointvec,
5776 	},
5777 	{
5778 		.procname	= "mldv1_unsolicited_report_interval",
5779 		.data		=
5780 			&ipv6_devconf.mldv1_unsolicited_report_interval,
5781 		.maxlen		= sizeof(int),
5782 		.mode		= 0644,
5783 		.proc_handler	= proc_dointvec_ms_jiffies,
5784 	},
5785 	{
5786 		.procname	= "mldv2_unsolicited_report_interval",
5787 		.data		=
5788 			&ipv6_devconf.mldv2_unsolicited_report_interval,
5789 		.maxlen		= sizeof(int),
5790 		.mode		= 0644,
5791 		.proc_handler	= proc_dointvec_ms_jiffies,
5792 	},
5793 	{
5794 		.procname	= "use_tempaddr",
5795 		.data		= &ipv6_devconf.use_tempaddr,
5796 		.maxlen		= sizeof(int),
5797 		.mode		= 0644,
5798 		.proc_handler	= proc_dointvec,
5799 	},
5800 	{
5801 		.procname	= "temp_valid_lft",
5802 		.data		= &ipv6_devconf.temp_valid_lft,
5803 		.maxlen		= sizeof(int),
5804 		.mode		= 0644,
5805 		.proc_handler	= proc_dointvec,
5806 	},
5807 	{
5808 		.procname	= "temp_prefered_lft",
5809 		.data		= &ipv6_devconf.temp_prefered_lft,
5810 		.maxlen		= sizeof(int),
5811 		.mode		= 0644,
5812 		.proc_handler	= proc_dointvec,
5813 	},
5814 	{
5815 		.procname	= "regen_max_retry",
5816 		.data		= &ipv6_devconf.regen_max_retry,
5817 		.maxlen		= sizeof(int),
5818 		.mode		= 0644,
5819 		.proc_handler	= proc_dointvec,
5820 	},
5821 	{
5822 		.procname	= "max_desync_factor",
5823 		.data		= &ipv6_devconf.max_desync_factor,
5824 		.maxlen		= sizeof(int),
5825 		.mode		= 0644,
5826 		.proc_handler	= proc_dointvec,
5827 	},
5828 	{
5829 		.procname	= "max_addresses",
5830 		.data		= &ipv6_devconf.max_addresses,
5831 		.maxlen		= sizeof(int),
5832 		.mode		= 0644,
5833 		.proc_handler	= proc_dointvec,
5834 	},
5835 	{
5836 		.procname	= "accept_ra_defrtr",
5837 		.data		= &ipv6_devconf.accept_ra_defrtr,
5838 		.maxlen		= sizeof(int),
5839 		.mode		= 0644,
5840 		.proc_handler	= proc_dointvec,
5841 	},
5842 	{
5843 		.procname	= "accept_ra_min_hop_limit",
5844 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
5845 		.maxlen		= sizeof(int),
5846 		.mode		= 0644,
5847 		.proc_handler	= proc_dointvec,
5848 	},
5849 	{
5850 		.procname	= "accept_ra_pinfo",
5851 		.data		= &ipv6_devconf.accept_ra_pinfo,
5852 		.maxlen		= sizeof(int),
5853 		.mode		= 0644,
5854 		.proc_handler	= proc_dointvec,
5855 	},
5856 #ifdef CONFIG_IPV6_ROUTER_PREF
5857 	{
5858 		.procname	= "accept_ra_rtr_pref",
5859 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
5860 		.maxlen		= sizeof(int),
5861 		.mode		= 0644,
5862 		.proc_handler	= proc_dointvec,
5863 	},
5864 	{
5865 		.procname	= "router_probe_interval",
5866 		.data		= &ipv6_devconf.rtr_probe_interval,
5867 		.maxlen		= sizeof(int),
5868 		.mode		= 0644,
5869 		.proc_handler	= proc_dointvec_jiffies,
5870 	},
5871 #ifdef CONFIG_IPV6_ROUTE_INFO
5872 	{
5873 		.procname	= "accept_ra_rt_info_max_plen",
5874 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
5875 		.maxlen		= sizeof(int),
5876 		.mode		= 0644,
5877 		.proc_handler	= proc_dointvec,
5878 	},
5879 #endif
5880 #endif
5881 	{
5882 		.procname	= "proxy_ndp",
5883 		.data		= &ipv6_devconf.proxy_ndp,
5884 		.maxlen		= sizeof(int),
5885 		.mode		= 0644,
5886 		.proc_handler	= addrconf_sysctl_proxy_ndp,
5887 	},
5888 	{
5889 		.procname	= "accept_source_route",
5890 		.data		= &ipv6_devconf.accept_source_route,
5891 		.maxlen		= sizeof(int),
5892 		.mode		= 0644,
5893 		.proc_handler	= proc_dointvec,
5894 	},
5895 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5896 	{
5897 		.procname	= "optimistic_dad",
5898 		.data		= &ipv6_devconf.optimistic_dad,
5899 		.maxlen		= sizeof(int),
5900 		.mode		= 0644,
5901 		.proc_handler   = proc_dointvec,
5902 	},
5903 	{
5904 		.procname	= "use_optimistic",
5905 		.data		= &ipv6_devconf.use_optimistic,
5906 		.maxlen		= sizeof(int),
5907 		.mode		= 0644,
5908 		.proc_handler	= proc_dointvec,
5909 	},
5910 #endif
5911 #ifdef CONFIG_IPV6_MROUTE
5912 	{
5913 		.procname	= "mc_forwarding",
5914 		.data		= &ipv6_devconf.mc_forwarding,
5915 		.maxlen		= sizeof(int),
5916 		.mode		= 0444,
5917 		.proc_handler	= proc_dointvec,
5918 	},
5919 #endif
5920 	{
5921 		.procname	= "disable_ipv6",
5922 		.data		= &ipv6_devconf.disable_ipv6,
5923 		.maxlen		= sizeof(int),
5924 		.mode		= 0644,
5925 		.proc_handler	= addrconf_sysctl_disable,
5926 	},
5927 	{
5928 		.procname	= "accept_dad",
5929 		.data		= &ipv6_devconf.accept_dad,
5930 		.maxlen		= sizeof(int),
5931 		.mode		= 0644,
5932 		.proc_handler	= proc_dointvec,
5933 	},
5934 	{
5935 		.procname	= "force_tllao",
5936 		.data		= &ipv6_devconf.force_tllao,
5937 		.maxlen		= sizeof(int),
5938 		.mode		= 0644,
5939 		.proc_handler	= proc_dointvec
5940 	},
5941 	{
5942 		.procname	= "ndisc_notify",
5943 		.data		= &ipv6_devconf.ndisc_notify,
5944 		.maxlen		= sizeof(int),
5945 		.mode		= 0644,
5946 		.proc_handler	= proc_dointvec
5947 	},
5948 	{
5949 		.procname	= "suppress_frag_ndisc",
5950 		.data		= &ipv6_devconf.suppress_frag_ndisc,
5951 		.maxlen		= sizeof(int),
5952 		.mode		= 0644,
5953 		.proc_handler	= proc_dointvec
5954 	},
5955 	{
5956 		.procname	= "accept_ra_from_local",
5957 		.data		= &ipv6_devconf.accept_ra_from_local,
5958 		.maxlen		= sizeof(int),
5959 		.mode		= 0644,
5960 		.proc_handler	= proc_dointvec,
5961 	},
5962 	{
5963 		.procname	= "accept_ra_mtu",
5964 		.data		= &ipv6_devconf.accept_ra_mtu,
5965 		.maxlen		= sizeof(int),
5966 		.mode		= 0644,
5967 		.proc_handler	= proc_dointvec,
5968 	},
5969 	{
5970 		.procname	= "stable_secret",
5971 		.data		= &ipv6_devconf.stable_secret,
5972 		.maxlen		= IPV6_MAX_STRLEN,
5973 		.mode		= 0600,
5974 		.proc_handler	= addrconf_sysctl_stable_secret,
5975 	},
5976 	{
5977 		.procname	= "use_oif_addrs_only",
5978 		.data		= &ipv6_devconf.use_oif_addrs_only,
5979 		.maxlen		= sizeof(int),
5980 		.mode		= 0644,
5981 		.proc_handler	= proc_dointvec,
5982 	},
5983 	{
5984 		.procname	= "ignore_routes_with_linkdown",
5985 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
5986 		.maxlen		= sizeof(int),
5987 		.mode		= 0644,
5988 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
5989 	},
5990 	{
5991 		.procname	= "drop_unicast_in_l2_multicast",
5992 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
5993 		.maxlen		= sizeof(int),
5994 		.mode		= 0644,
5995 		.proc_handler	= proc_dointvec,
5996 	},
5997 	{
5998 		.procname	= "drop_unsolicited_na",
5999 		.data		= &ipv6_devconf.drop_unsolicited_na,
6000 		.maxlen		= sizeof(int),
6001 		.mode		= 0644,
6002 		.proc_handler	= proc_dointvec,
6003 	},
6004 	{
6005 		.procname	= "keep_addr_on_down",
6006 		.data		= &ipv6_devconf.keep_addr_on_down,
6007 		.maxlen		= sizeof(int),
6008 		.mode		= 0644,
6009 		.proc_handler	= proc_dointvec,
6010 
6011 	},
6012 	{
6013 		/* sentinel */
6014 	}
6015 };
6016 
6017 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6018 		struct inet6_dev *idev, struct ipv6_devconf *p)
6019 {
6020 	int i;
6021 	struct ctl_table *table;
6022 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6023 
6024 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6025 	if (!table)
6026 		goto out;
6027 
6028 	for (i = 0; table[i].data; i++) {
6029 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6030 		table[i].extra1 = idev; /* embedded; no ref */
6031 		table[i].extra2 = net;
6032 	}
6033 
6034 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6035 
6036 	p->sysctl_header = register_net_sysctl(net, path, table);
6037 	if (!p->sysctl_header)
6038 		goto free;
6039 
6040 	return 0;
6041 
6042 free:
6043 	kfree(table);
6044 out:
6045 	return -ENOBUFS;
6046 }
6047 
6048 static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
6049 {
6050 	struct ctl_table *table;
6051 
6052 	if (!p->sysctl_header)
6053 		return;
6054 
6055 	table = p->sysctl_header->ctl_table_arg;
6056 	unregister_net_sysctl_table(p->sysctl_header);
6057 	p->sysctl_header = NULL;
6058 	kfree(table);
6059 }
6060 
6061 static int addrconf_sysctl_register(struct inet6_dev *idev)
6062 {
6063 	int err;
6064 
6065 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6066 		return -EINVAL;
6067 
6068 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6069 				    &ndisc_ifinfo_sysctl_change);
6070 	if (err)
6071 		return err;
6072 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6073 					 idev, &idev->cnf);
6074 	if (err)
6075 		neigh_sysctl_unregister(idev->nd_parms);
6076 
6077 	return err;
6078 }
6079 
6080 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6081 {
6082 	__addrconf_sysctl_unregister(&idev->cnf);
6083 	neigh_sysctl_unregister(idev->nd_parms);
6084 }
6085 
6086 
6087 #endif
6088 
6089 static int __net_init addrconf_init_net(struct net *net)
6090 {
6091 	int err = -ENOMEM;
6092 	struct ipv6_devconf *all, *dflt;
6093 
6094 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6095 	if (!all)
6096 		goto err_alloc_all;
6097 
6098 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
6099 	if (!dflt)
6100 		goto err_alloc_dflt;
6101 
6102 	/* these will be inherited by all namespaces */
6103 	dflt->autoconf = ipv6_defaults.autoconf;
6104 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
6105 
6106 	dflt->stable_secret.initialized = false;
6107 	all->stable_secret.initialized = false;
6108 
6109 	net->ipv6.devconf_all = all;
6110 	net->ipv6.devconf_dflt = dflt;
6111 
6112 #ifdef CONFIG_SYSCTL
6113 	err = __addrconf_sysctl_register(net, "all", NULL, all);
6114 	if (err < 0)
6115 		goto err_reg_all;
6116 
6117 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
6118 	if (err < 0)
6119 		goto err_reg_dflt;
6120 #endif
6121 	return 0;
6122 
6123 #ifdef CONFIG_SYSCTL
6124 err_reg_dflt:
6125 	__addrconf_sysctl_unregister(all);
6126 err_reg_all:
6127 	kfree(dflt);
6128 #endif
6129 err_alloc_dflt:
6130 	kfree(all);
6131 err_alloc_all:
6132 	return err;
6133 }
6134 
6135 static void __net_exit addrconf_exit_net(struct net *net)
6136 {
6137 #ifdef CONFIG_SYSCTL
6138 	__addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
6139 	__addrconf_sysctl_unregister(net->ipv6.devconf_all);
6140 #endif
6141 	kfree(net->ipv6.devconf_dflt);
6142 	kfree(net->ipv6.devconf_all);
6143 }
6144 
6145 static struct pernet_operations addrconf_ops = {
6146 	.init = addrconf_init_net,
6147 	.exit = addrconf_exit_net,
6148 };
6149 
6150 static struct rtnl_af_ops inet6_ops __read_mostly = {
6151 	.family		  = AF_INET6,
6152 	.fill_link_af	  = inet6_fill_link_af,
6153 	.get_link_af_size = inet6_get_link_af_size,
6154 	.validate_link_af = inet6_validate_link_af,
6155 	.set_link_af	  = inet6_set_link_af,
6156 };
6157 
6158 /*
6159  *	Init / cleanup code
6160  */
6161 
6162 int __init addrconf_init(void)
6163 {
6164 	struct inet6_dev *idev;
6165 	int i, err;
6166 
6167 	err = ipv6_addr_label_init();
6168 	if (err < 0) {
6169 		pr_crit("%s: cannot initialize default policy table: %d\n",
6170 			__func__, err);
6171 		goto out;
6172 	}
6173 
6174 	err = register_pernet_subsys(&addrconf_ops);
6175 	if (err < 0)
6176 		goto out_addrlabel;
6177 
6178 	addrconf_wq = create_workqueue("ipv6_addrconf");
6179 	if (!addrconf_wq) {
6180 		err = -ENOMEM;
6181 		goto out_nowq;
6182 	}
6183 
6184 	/* The addrconf netdev notifier requires that loopback_dev
6185 	 * has it's ipv6 private information allocated and setup
6186 	 * before it can bring up and give link-local addresses
6187 	 * to other devices which are up.
6188 	 *
6189 	 * Unfortunately, loopback_dev is not necessarily the first
6190 	 * entry in the global dev_base list of net devices.  In fact,
6191 	 * it is likely to be the very last entry on that list.
6192 	 * So this causes the notifier registry below to try and
6193 	 * give link-local addresses to all devices besides loopback_dev
6194 	 * first, then loopback_dev, which cases all the non-loopback_dev
6195 	 * devices to fail to get a link-local address.
6196 	 *
6197 	 * So, as a temporary fix, allocate the ipv6 structure for
6198 	 * loopback_dev first by hand.
6199 	 * Longer term, all of the dependencies ipv6 has upon the loopback
6200 	 * device and it being up should be removed.
6201 	 */
6202 	rtnl_lock();
6203 	idev = ipv6_add_dev(init_net.loopback_dev);
6204 	rtnl_unlock();
6205 	if (IS_ERR(idev)) {
6206 		err = PTR_ERR(idev);
6207 		goto errlo;
6208 	}
6209 
6210 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6211 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
6212 
6213 	register_netdevice_notifier(&ipv6_dev_notf);
6214 
6215 	addrconf_verify();
6216 
6217 	rtnl_af_register(&inet6_ops);
6218 
6219 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
6220 			      NULL);
6221 	if (err < 0)
6222 		goto errout;
6223 
6224 	/* Only the first call to __rtnl_register can fail */
6225 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, NULL);
6226 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, NULL);
6227 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
6228 			inet6_dump_ifaddr, NULL);
6229 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
6230 			inet6_dump_ifmcaddr, NULL);
6231 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
6232 			inet6_dump_ifacaddr, NULL);
6233 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
6234 			inet6_netconf_dump_devconf, NULL);
6235 
6236 	ipv6_addr_label_rtnl_register();
6237 
6238 	return 0;
6239 errout:
6240 	rtnl_af_unregister(&inet6_ops);
6241 	unregister_netdevice_notifier(&ipv6_dev_notf);
6242 errlo:
6243 	destroy_workqueue(addrconf_wq);
6244 out_nowq:
6245 	unregister_pernet_subsys(&addrconf_ops);
6246 out_addrlabel:
6247 	ipv6_addr_label_cleanup();
6248 out:
6249 	return err;
6250 }
6251 
6252 void addrconf_cleanup(void)
6253 {
6254 	struct net_device *dev;
6255 	int i;
6256 
6257 	unregister_netdevice_notifier(&ipv6_dev_notf);
6258 	unregister_pernet_subsys(&addrconf_ops);
6259 	ipv6_addr_label_cleanup();
6260 
6261 	rtnl_lock();
6262 
6263 	__rtnl_af_unregister(&inet6_ops);
6264 
6265 	/* clean dev list */
6266 	for_each_netdev(&init_net, dev) {
6267 		if (__in6_dev_get(dev) == NULL)
6268 			continue;
6269 		addrconf_ifdown(dev, 1);
6270 	}
6271 	addrconf_ifdown(init_net.loopback_dev, 2);
6272 
6273 	/*
6274 	 *	Check hash table.
6275 	 */
6276 	spin_lock_bh(&addrconf_hash_lock);
6277 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6278 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
6279 	spin_unlock_bh(&addrconf_hash_lock);
6280 	cancel_delayed_work(&addr_chk_work);
6281 	rtnl_unlock();
6282 
6283 	destroy_workqueue(addrconf_wq);
6284 }
6285